AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PUEBLO CO 357 AM MDT SAT JUN 2 2007 .SHORT TERM... (TODAY AND TONIGHT) CURRENTLY...06Z TEMPERATURES WERE ROUGHLY 1-3 DEGREES FROM WHERE THEY WERE LAST NIGHT. OLD PESKY UPPER LOW CONTINUED TO SPIN OVER THE NORTHERN PLAINS...AND IS A LITTLE FURTHER EAST COMPARED TO YESTERDAY. STILL HAVE SOME CONVECTIVE DEBRIS CLOUDS FLOATING AROUND THE CENTRAL ROCKIES PER SATELLITE IMAGERY. RELATIVELY FLAT WEST NORTHWEST FLOW REMAINS OVER THE CENTRAL ROCKIES PER WATER VAPOR SATELLITE IMAGERY AND RUC MODEL UPPER AIR ANALYSES ANIMATION. HARD PRESSED TO FIND THE MIDLEVEL SHORTWAVE TO HELP ENHANCE CONVECTION TODAY...SO IT COULD BE A CRAP SHOOT IF AND WHERE THINGS FORM TODAY. TODAY AND TONIGHT...HINTS OF A H3-H2 POTENTIAL VORTICITY LOBE MOVING INTO THE CENTRAL ROCKIES LATER THIS AFTERNOON. THIS COULD HELP ENHANCE THE DIURNAL CONVECTION TODAY. SURFACE BASED CAPES ARE PROGGED TO BE 200 - 1200 J/KG WITH LIFTED INDICES OF 0C TO -4C. THE GREATEST INSTABILITY MAY LIE ALONG AND WEST OF THE I-25 CORRIDOR THIS AFTERNOON WHERE PRE-STORM ENVIRONMENT SURFACE BASED CAPES COULD BE AROUND 1200 J/KG ACROSS THE SOUTHERN FOOTHILLS NEAR WALSENBURG AND TRINIDAD. VERY MARGINAL VERTICAL SHEAR...0-6KM AROUND 30-35 KTS...SO COULD NOT RULE OUT A MARGINAL SEVERE THUNDERSTORM PRODUCING AROUND PENNY SIZE HAIL...BUT PRIMARILY THE THREAT WOULD BE PEA-MARBLE. PRE-STORM ENVIRONMENT DOWNDRAFT CAPES ARE PROGGED TO BE 1K-1.5K J/KG...SO THERE COULD BE MARGINALLY STRONG WIND GUSTS NEAR INTENSE THUNDERSTORMS. ACROSS THE CONTINENTAL DIVIDE AND SAN LUIS VALLEY...SOUNDING INVERTED-V THERMAL STRUCTURES SUPPORT MAINLY GUSTY WINDS...MAYBE SOME PEA SIZE HAIL...AND LITTLE OR NO RAINFALL. ACTUALLY...NO THUNDERSTORMS OCCURRED IN THIS AREA YESTERDAY PER POST RADAR/LIGHTNING ANALYSES AND THAT COULD VERY HAPPEN AGAIN TODAY. MUCH OF THE CONVECTIVE PRECIPITATION SHOULD DIE AROUND SUNSET WITH DISSIPATING CONVECTIVE DEBRIS CLOUDS LATER TONIGHT. CURRENT FORECAST TEMPERATURES LOOK ON TRACK AND CLOSE TO A BLEND OF MOS GUIDANCE. METZE .LONG TERM... (SUNDAY THROUGH FRIDAY) NOT MUCH CHANGE FROM PREVIOUS FCST PACKAGE WITH NORTHWEST FLOW ACROSS THE AREA THROUGH MONDAY SENDING ANOTHER REINFORCING NORTHERLY SURGE THROUGH THE EASTERN PARTS OF THE FORECAST AREA ON SUNDAY. TEMPS WARM THROUGH THE PERIOD AS AIR MASS MODERATES SOME ACROSS THE SE PLAINS. WITH EASTERLY LOW LVL FLOW KEEPING DEW POINTS IN THE MID 40S TO LOWER 50S ACROSS THE SOUTHEAST PLAINS...AND LESS OF A CAP ALOFT...EXPECT ISOLATED TO SCATTERED AFTERNOON THUNDERSTORMS EACH DAY THROUGH MONDAY. THOUGH SYNOPTIC LIFT DOESN/T APPEAR OVERLY IMPRESSIVE...WEAK SHORTWAVE ENERGY AS EVIDENT IN H2-H3 POTENTIAL VORTICITY FIELDS WILL BE MOVING ACROSS THE AREA EACH DAY. SOME MID/HIGH LVL MOISTURE WILL BE INCREASING ACROSS WRN AREAS FOR SUN...WHICH SHOULD RESULT IN A SLIGHT INCREASE IN THE POTENTIAL FOR THUNDERSTORMS ACROSS WRN AREAS AS WELL...ESP ON SUN. AS FOR THUNDERSTORM THREATS...MAINLY GUSTY WINDS...LIGHTNING...AND SOME LOCALIZED LIGHT TO MODERATE RAINFALL POSSIBLE ACROSS THE WRN AREAS. ACROSS THE EAST...ENOUGH CAPE PRESENT (RANGING FROM 700 TO 1400 J/KG ALONG THE EASTERN SLOPES OF THE SE MTS/ADJACENT PLAINS) AND DEEP LAYER SHEARS (AROUND 30-40KTS) TO SUGGEST POSSIBILITY OF A COUPLE STRONG TO MARGINALLY SEVERE STORMS ACROSS PORTIONS OF THE SE PLAINS...MAINLY ACROSS THE ERN SLOPES OF THE SE MTNS TO THE I-25 CORRIDOR. WRN US UPPER RIDGE TRANSLATES EASTWARD OVER THE US ROCKIES FOR TUES...BRINGING DRIER AND MORE SUMMER LIKE TEMPS TO THE REGION. HIGH TEMPS SHOULD BE PUSHING INTO THE 90S ACROSS THE SE PLAINS...WITH 80S HIGH VALLEYS...AND 60S/70S FOR THE MOUNTAINS...THUS...MELTING OF HIGHER ELEVATION SNOW PACK SHOULD PEAK AGAIN BY MID WEEK. 00Z GFS HAS TRENDED TOWARDS THE ECMWF SOLUTION FROM PAST FEW RUNS...WITH NEXT OPEN TROF MOVING ACROSS THE NRN US ROCKIES ON WED. THEN GFS/ECMWF SEEM TO SUGGEST A MORE PROGRESSIVE PATTERN FOR LATE IN THE WEEK WITH BREEZY SOUTHWEST FLOW ACROSS THE AREA AHEAD OF THE NEXT FAST MOVING UPPER TROF WHICH MOVES ACROSS THE NRN US ROCKIES BY FRI. THUS SHOULD SEE SUMMER LIKE TEMPS CONTINUE THROUGH WEDNESDAY WITH SLIGHTLY COOLER TEMPS (THOUGH STILL ABOVE CLIMATOLOGICAL NORMALS) FOR THURS AND FRI. NO CHANGES MADE BEYOND DAY 5. -KT && .AVIATION... THERE WILL BE THE POTENTIAL FOR ISOLATED-SCATTERED VFR THUNDERSTORMS NEAR COS AND PUB FLIGHT ZONES BETWEEN 18Z/02 - 03Z/03. ERRATIC WINDS AND PEA-MARBLE SIZE HAIL COULD OCCUR WITH THUNDERSTORMS NEAR COS/PUB AIRPORTS. FOR THE ALS FLIGHT ZONES...ISOLATED VFR THUNDERSTORMS COULD OCCUR BETWEEN 19Z/02 - 03Z/03 WITH THE ERRATIC WINDS THE MAIN THREAT. METZE && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 17/31 co AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE UPTON NY 841 PM EDT SAT JUN 2 2007 .SYNOPSIS... A FRONTAL BOUNDARY OVER NORTH CENTRAL NEW ENGLAND IS RESULTING IN SCATTERED (SOME SEVERE) AFTERNOON/EVENING CONVECTION TODAY. LOW PRESSURE...EXTRA-TROPICAL REMNANTS OF BARRY...WILL MOVE UP THE EAST COAST REACHING OUR REGION LATE IN THE DAY ON SUNDAY. HEAVY RAIN AND HIGH SURF ARE THREATS ALONG WITH WINDY CONDITIONS. THIS LOW WILL GRADUALLY MOVE NORTH OF THE AREA BY LATE MONDAY. A COLD FRONT IS EXPECTED TO MORE THROUGH LATE TUESDAY ACCOMPANIED BY THUNDERSTORMS...POSSIBLY SEVERE. HIGH PRESSURE THEN BUILDS OVER THE AREA WEDNESDAY AND OFF THE SOUTHEAST COAST THURSDAY. THE HIGH WILL REMAIN OFF THE COAST FRIDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... A SEVERE THUNDERSTORM WATCH OVER CENTRAL NEW ENGLAND AS SCATTERED CONVECTION DEVELOPS IN RESPONSE TO DAY TIME HEATING. LATEST LAPS AND RUC CONVECTIVE ANALYZES (CAPE/LIFTED INDEX) SUGGEST THAT THE BULK OF THE CONVECTION WILL REMAIN INLAND. THIS WAS THE REASON FOR THE FORECAST UPDATE EARLY THIS AFTERNOON. WITH MEAN FLOW BASICALLY WEST TO EAST TODAY...MARINE ENVIRONMENT PREVENTS CONVECTION FROM REACHING/DEVELOPING ON LONG ISLAND AND ONLY A SLIGHT CHANCE FOR THE CITY. CONVECTION DISSIPATES WITH LOSS OF HEATING. MOS NUMBERS USED FOR MIN TEMPS WITH DEWS IN THE MID 60S...UNIFORM TEMPS HOLD OVERNIGHT WITH EXCEPTION OF NY CITY HEAT ISLAND. HAVE FORECAST PATCHY FOG IN THE AM (EXCEPT NYC) AND WATERS. EXPECTING SOME 3-5 SM VSBY IN HAZE/BR AS TEMPS LOWER TO NEAR SATURATION. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... EXTRA-TROPICAL REMNANTS OF TD BARRY MOVE UP THE COAST AS HAS BEEN ANTICIPATED FOR SOME TIME. MODELS IN GENERAL AGREEMENT WITH MINOR VARIATIONS ON TIMING AND TRACK. NCEP NAM IS FASTER THAN GFS ABOUT 6 HOURS. REGARDLESS OF THIS...EXPECT THIS SYSTEM TO MAKE IT`S PRESENCE KNOWN SOONER THAN LATER. THICKENING CIRRUS NOW APPROACHING DC IS HERE BY MORNING AND EXPECTING A CLOUDY SUNDAY OVERALL AS CLOUDS THICKEN AND LOWER. RAIN SHIELD EXPANDS TO THE NORTH WITH BAROCLINIC BAND SEEN NORTH OF THE LOW (OVER-RUNNING). EXPECTING THE RAIN TO SPREAD IN FROM THE SOUTH BEFORE SUNSET. THIS RAIN IS WILL BE STRATIFORM IN NATURE. LOWER TEMPS USED FOR SUNDAY IN RESPONSE TO THE CLOUDINESS. CLOSE TO FWC GUIDANCE. LOW LEVEL STABILITY PREVENTS GALE FORCE WIND GUSTS ON LAND. WINDS SHOULD BE FAIRLY STEADY AT 20 TO 25 MPH TOMORROW EVENING WITH GUSTS TO 25 TO 35 MPH. THIS IS ALL BELOW WIND ADVISORY CRITERIA. LOW GRADUALLY PULLS INTO NEW ENGLAND ON MONDAY WITH A MORE SHOWERY TYPE OF PRECIPITATION. SEE HYDROLOGY SECTION FOR DISCUSSION ON RAINFALL. HIGH SURF IS ALSO A HAZARD (TOO EARLY FOR AN ADVISORY YET) WITH 10 TO 12 FT SEAS OFF SHORE RESULTING IN RIP TIDES AND AT LEAST SOME BEACH EROSION FOR THE OCEAN BEACHES ON LONG ISLAND. && .LONG TERM /TUESDAY THROUGH SATURDAY/... TROFFING OVER THE EASTERN U.S. DOMINATES TO START AS COASTAL LOW IS ABSORBED IN TO THE SYNOPTIC SCALE LOW OVER SOUTHERN QUEBEC. THE SYNOPTIC CANADIAN LOW DRIVES A COLD FRONT THOUGHT THE REGION ON TUESDAY FOLLOWED BY HIGH PRESSURE. COLD FRONT ON TUESDAY AFTERNOON HAS POTENTIAL FOR SEVERE CONVECTION DUE TO DYNAMICAL FORCING THOUGH WIND SHEAR PROFILE IS RATHER WEAK BASED ON GFS WIND PROFILE. CANADIAN HIGH BUILDS IN FOR WEDNESDAY WITH LOW HUMIDITY AND MID 70 TEMPS. THE LONG WAVE TROUGH RETROGRADES WEST ACROSS CANADA WHICH BREAKS DOWN THE OMEGA BLOCK ALLOWING FOR SHORTWAVE TROUGHING OVER THE WESTERN U.S. THIS RESULTS IN SHORT WAVE RIDGING AND WARMING TREND THURSDAY INTO FRIDAY FOR THE NORTHEAST. 12Z GFS SUGGESTION PCPN ALONG THE WARM FRONT...BUT FOR NOW WE`LL KEEP IT DRY AND FLOW HPC GUIDANCE ON THIS. EXPECT A RETURN OF HUMIDITY ON FRIDAY AND TEMPS A GOOD 5 DEGREES WARMER THAN PREVIOUSLY FORECAST. CHANCE FOR AFTN/EVENING CONVECTION WITH RETURN OF MT AIRMASS. SHORT WAVE IN THE GREAT LAKES COULD DRAG A COLD FRONT INTO THE REGION ON SATURDAY...BUT BELIEVE THAT WITH WOULD BE WEAK BASED ON UPPER LEVEL RIDGING. PCPN IN 12Z GFS FOR SATURDAY EVENING IS FROM MODEL CONVECTIVE BOMB OVER ILLINOIS AND IS LIKELY ERRONEOUS OR WILL DISSIPATE LONG BEFORE REACHING THE EAST COAST. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... ALL CONVECTIVE ACTIVITY ACROSS THE LOCAL AREA SEEMS TO HAVE CEASED...ALTHOUGH A LINE STILL EXISTS TO THE NORTH ACROSS ULSTER...DUTCHESS AND SULLIVAN COUNTIES. THIS LINE IS MOVING IN A EASTERLY DIRECTION AND SHOULD NOT POSE A THREAT TO ANY OF THE TERMINALS. WOULD NOT BE SURPRISED TO SEE A CELL POP UP FROM ANY OUTFLOW BOUNDARIES INTERSECTING EACH OTHER OR EVEN WITH THE SEABREEZE BOUNDARY THIS EVENING...BUT THE LIKELIHOOD OF THIS OCCURRING IS RATHER SMALL SO HAVE REMOVED ALL CB APPENDAGES IN THE 00Z TAFS. OTHER THAN SOME CONVECTIVE CLOUD DEBRIS CIGS WILL REMAIN VFR. PLAYING THE PERSISTENCE GAME WITH VSBYS HOWEVER...WHICH WITH NO REAL CHANGE IN AIRMASS AND DEWPOINTS A BIT HIGHER TONIGHT...WILL LIKELY FALL INTO THE MVFR CATEGORY (POSSIBLY ISOLATED IFR) IN HZ/BR AS SOUTHERLY WINDS LIGHTEN. MOS GUIDANCE HAS BEEN HINTING AT VLIFR STRATUS AT KGON OVER THE LAST 24 HOURS AND WITH DEWPOINTS CLOSE TO WATER TEMPS...THINK IT IS A POSSIBILITY...SO HAVE INCLUDED IT AS A TEMPO BETWEEN 08Z AND 12Z. A COLD FRONT OVER NORTHERN NEW ENGLAND WILL DROP DOWN TONIGHT AND SUN. IN THE MEANTIME...THE REMNANTS OF BARRY...CURRENTLY OVER THE SOUTHEAST COAST WILL TRACK UP THE EASTERN SEABOARD WITH CLOUDS LOWERING AND THICKENING ON SUN. THE BOUNDARY TO THE NORTH SHOULD BE ABLE TO TRIGGER SOME SHOWERS BY AFTERNOON AND THEN RAIN AND MVFR CONDITIONS WILL BEGIN TO OVERSPREAD THE REGION FROM S TO N JUST BEFORE 00Z. AFTER 00Z SUNDAY...MVFR TO IFR CONDITIONS WILL PREVAIL AS REMNANTS OF BARRY MOVE INTO THE AREA SUNDAY NIGHT INTO MONDAY MORNING. CONDITIONS WILL IMPROVE A BIT MONDAY AND MONDAY NIGHT...BUT MVFR CONDITIONS ARE STILL POSSIBLE THROUGH TUESDAY. A COLD FRONT WILL MOVE THROUGH TUESDAY EVE WITH SCT TSTMS AND LOCALIZED MVFR TO IFR CONDITIONS. VFR CONDITIONS EXPECTED BEHIND THE FRONT AND CONTINUING THROUGH THURSDAY AS HIGH PRESSURE SETTLES IN. && .MARINE... BUOY OBS ACROSS THE COASTAL WATERS CONTINUE TO HOLD STEADY WITH 3 FT SEAS. THE 12Z WAVEWATCH GUIDANCE CONTINUES TO OVER FORECAST SHOWING 4 TO 5 FT SEAS INITIALLY. HAVE UNDERCUT THE WNA GUIDANCE FOR TONIGHT INTO MON AND HELD SEAS IN THE 3 TO 4 FT RANGE DURING THIS PERIOD. PERSISTENT SW FLOW TONIGHT WILL BECOME SOUTHERLY SUN THEN SE LATE IN THE DAY AS THE COASTAL LOW MOVES NEAR THE NC OUTER BANKS BY SUN EVENING. WINDS SHOULD REMAIN BELOW SCA LEVELS DURING THE DAY ON SUN...ALTHOUGH SOME GUSTS NEAR 20 KT WILL BE LIKELY ON THE OCEAN DURING THE LATER AFTERNOON PERIOD. REMNANTS OF BARRY APPROACH SUN NIGHT AND MOVE THROUGH THE AREA ON MON. 12Z MODELS ARE IN DECENT AGREEMENT WITH THE TRACK...BUT STILL SHOW SOME TIMING DIFFERENCES. FOLLOWED THE SLOWER GFS SOLN WHICH IS CLOSE TO THE 09Z SREF AND THE LATEST NHC TRACK OF THE EXTRATROPICAL SYSTEM. THIS BRINGS THE LOW CENTER ACROSS LONG ISLAND MON AFTERNOON. EXPECT A PERIOD OF GALE FORCE WINDS ACROSS THE OCEAN WATERS SUN NIGHT INTO EARLY MON MORNING AS THE LOW APPROACHES WITH A STRONG LOW LEVEL JET AND SFC PRESSURE GRADIENT. HAVE POSTED GALES ON THE OCEAN ZONES FROM 00Z-14Z MON...AND SCA FOR THE SAME TIME PERIOD ON THE SOUND/HARBOR AND BAYS. LOW MOVES AWAY MON NIGHT WITH MDT W FLOW BECOMING SW IN ITS WAKE...THEN SOUTHERLY FLOW ON TUE AHEAD OF A COLD FRONT. THIS FRONT MOVES OFFSHORE TURNING THE WINDS TO WEST TUE NIGHT...THEN QUIET WX WITH LIGHT WINDS EXPECTED FOR WED AS HIGH PRESSURE BUILDS INTO THE REGION. FOLLOWED WNA GUIDANCE FOR SEA FCST SUN NIGHT AND BEYOND WITH THE LOW PASSAGE...WITH SEAS BUILDING TO 8 TO 13 FT ACROSS THE OCEAN ON MON. EXTENDED PERIOD OF SCA FOR HAZARDOUS SEAS WILL LIKELY BE NEEDED AFTER THE LOW PASSES...AS WNA GUIDANCE INDICATES IT COULD BE SOMETIME WED BEFORE SEAS SUBSIDE BELOW 5 FT. && .HYDROLOGY... ISOLATED 1 INCH AMOUNT IN CONVECTION OVER THE INTERIOR THIS EVENING. MAIN EVENT IS SUNDAY NIGHT WITH 1 TO 2 INCHES OF WIDESPREAD PRECIPITATION. DUE TO THE STRATIFORM NATURE OF THIS PRECIPITATION...DO NOT FORESEE WIDESPREAD FLOODING PROBLEMS. THUS THERE IS NOT FLOOD WATCH BEING ISSUED. WOULD EXPECT SOME PONDING THAT COULD PROMPT SOME SHORT FUSED FLOOD ADVISORIES. ANOTHER LOCALIZED 0.5 TO 1 INCH AMOUNTS ON MONDAY AS THE LOW MOVES INTO NEW ENGLAND. MULTI-CELLULAR CONVECTION TUESDAY AFTERNOON IS EXPECTED TO BE FAST MOVING. LOCALIZED 1 TO 2 INCH AMOUNTS IN POSSIBLE TRAINING OF CONVECTIVE CELLS AHEAD OF COLD FRONT. && .TIDES/COASTAL FLOODING... THERE IS SOME POTENTIAL FOR LOCALIZED MINOR COASTAL FLOODING SUNDAY NIGHT AND MIDDAY MONDAY...DUE TO A PERIOD OF STRONG E/NE WINDS AS THE COASTAL LOW APPROACHES. HOWEVER..IT APPEARS THAT RELATIVELY LOWER ASTRONOMICAL TIDES...AS WE MOVE AWAY FROM THE FULL MOON OF MAY 31...AND FORTUNATE TIMING OF THE HIGH TIDE CYCLES WILL PREVENT MORE SIGNIFICANT PROBLEMS. THE HIGHER OF THE ASTRONOMICAL TIDES OCCURS LATE SUN EVENING...BUT MODEL GUIDANCE INDICATES THAT EASTERLY FETCH WILL NOT HAVE ENOUGH DURATION UP TO THAT POINT TO PRODUCE THE 1.5 TO 2 FOOT DEPARTURES NEEDED TO REACH MINOR FLOODING BENCHMARKS. GFS GUIDANCE DOES SHOW THESE DEPARTURES BEING REACHED BY EARLY TUE MORNING...BUT ASTRO TIDES WILL BE GOING OUT BY THAT TIME. THERE IS SOME CHANCE THAT WATER LEVELS WILL RISE FASTER THAN FCST AND CAUSE MINOR FLOODING IN WRN LI SOUND AND THE USUAL SUSPECT LOCATIONS SUCH AS FREEPORT ALONG THE SOUTH SHORE...BUT THIS IS A LOW PROBABILITY SCENARIO AT THIS TIME. MODERATE FLOODING ON SUN NIGHT WOULD REQUIRE 2.5 TO 3.5 FOOT DEPARTURES WHICH APPEAR VERY UNLIKELY. FOR MIDDAY MONDAY...THE ASTRONOMICAL HIGH TIDES WILL BE ABOUT A FOOT LOWER...REQUIRING AROUND 2.5 FOOT DEPARTURES FOR MINOR FLOODING. DEPENDING ON HOW LONG STRONG E/NE FLOW CONTINUES AS THE LOW APPROACHES LONG ISLAND...SUCH DEPARTURES COULD BE POSSIBLE IN THE WRN SOUND AND SOUTH SHORE BACK BAYS. MODERATE FLOODING ON MON WOULD REQUIRE 3.5 TO 4 FOOT DEPARTURES WHICH AGAIN APPEAR VERY UNLIKELY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM 8 PM SUNDAY TO 10 AM EDT MONDAY FOR ANZ330-335-338-340-345. GALE WARNING FROM 8 PM SUNDAY TO 10 AM EDT MONDAY FOR ANZ350- 353-355. && $$ ct AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 850 PM CDT SUN JUN 3 2007 .DISCUSSION... ISSUED 847 PM CDT SUN JUN 3 2007 NOT MUCH TO CHANGE WITH THE EVENING UPDATE. THE UPPER TROUGH IS STILL THE PRIMARY INFLUENCE ON THE WEATHER IN CENTRAL ILLINOIS. EXPECT MUCH OF THE SAME THE REST OF THE NIGHT. DESPITE THE WEAKENING INSTABILITY...A FEW THUNDERSTORMS ARE LINGERING ACROSS IOWA. WE MAY SEE A RUMBLE OF THUNDER THROUGH MIDNIGHT IN OUR CWA AS WELL...SO I LEFT THAT IN THE GRIDS. THE SHOWERS SHOULD DECREASE AS MORNING APPROACHES. TOMORROW WILL FEATURE SHOWERS AND A FEW STORMS IN THE AFTERNOON...DUE TO DESTABILIZATION WITH DAYTIME HEATING. THE COLD POOL ALOFT WILL BE FARTHER EAST...BUT WE WILL STILL SEE STEEP LOW LEVEL LAPSE RATES IN THE AFTERNOON. SHIMON && .AVIATION... ISSUED 621 PM CDT SUN JUN 3 2007 FOR THE 00Z TAFS SHOWERS WILL CONTINUE THROUGH MID EVENING...WITH AN ISOLATED THUNDERSTORM ALSO POSSIBLE. INSTABILITY LOOKS FAVORABLE ENOUGH ON RUC SOUNDINGS TO KEEP A VCTS THROUGH 03-04Z. STORMS LINGERED A LITTLE LONGER THAN THAT LAST NIGHT...SO WILL KEEP AN EYE ON UPSTREAM DEVELOPMENT FOR POSSIBLE UPDATES. CIGS AND VIS READINGS SHOULD REMAIN VFR...WITH ONLY A VERY SHORT PERIOD OF MVFR POSSIBLE. NON OF THE SHOWERS OR STORMS WILL LAST LONG ENOUGH IN ONE PLACE TO WARRANT PUTTING IN ANY IFR CONDITIONS THIS EVENING. FOG SHOULD NOT BE A PROBLEM LATER TONIGHT...AS WINDS SHOULD INCREASE TOWARD MORNING. SHIMON && .PREV DISCUSSION... ISSUED 209 PM CDT SUN JUN 3 2007 MAIN ISSUE WITH THIS FORECAST PACKAGE WILL BE LOW POPS OVER THE NEXT 24 TO 36 HOURS...AS UPPER LOW GRADUALLY OPENS UP AND MOVES AWAY FROM THE REGION. IN THE LONGER-TERM...EMPHASIS WILL BE ON EVOLVING UPPER AIR PATTERN...AND THE TIMING OF THE NEXT SYSTEM BY THE END OF THE WEEK. LATEST SURFACE CHART SHOWS LOW PRESSURE CENTERED OVER SOUTHEAST WISCONSIN...WITH WEAK FRONTAL BOUNDARY EXTENDING INTO WEST-CENTRAL INDIANA. FURTHER WEST...A WEAK TROUGH/WIND-SHIFT LINE IS EVIDENT ACROSS IOWA. ALOFT...STRONG RIDGE IS BUILDING ACROSS THE WESTERN CONUS...WHILE PERSISTENT LOW OVER THE UPPER MIDWEST IS FINALLY GETTING A NUDGE EASTWARD. SHORT TERM...TONIGHT THROUGH WEDNESDAY WIDELY SCATTERED SHOWERS/STORMS WILL CONTINUE THIS EVENING...BUT CONVECTION WILL QUICKLY FADE AWAY ONCE DAYTIME INSTABILITY IS LOST. BEST AREAL COVERAGE OF SHOWERS WILL BE ACROSS THE FAR NORTHERN KILX CWA...ALONG AND NORTH OF A CANTON TO MINONK LINE...AIDED BY APPROACHING SURFACE TROUGH. WILL GO WITH SCT/ISOLATED WORDING THIS EVENING ACROSS THE CENTRAL AND NORTHERN ZONES...WITH DRY CONDITIONS EXPECTED AFTER MIDNIGHT. WILL ONCE AGAIN SEE SCATTERED SHOWERS/STORMS POPPING UP ACROSS CENTRAL ILLINOIS ON MONDAY...AS UPPER SYSTEM SHIFTS INTO THE GREAT LAKES. BASED ON ORIENTATION OF UPPER COLD POOL...BEST AREAL COVERAGE OF PRECIP SHOULD BE ACROSS THE E/NE CWA. WILL AGAIN GO WITH SCT WORDING FOR MONDAY...WITH 50 POPS ACROSS THE E/NE TAPERING TO 30S ACROSS THE FAR W. WITH PLENTY OF CLOUD COVER AROUND...TEMPS WILL BE HELD DOWN. AFTERNOON HIGHS WILL ONLY BE IN THE LOWER TO MIDDLE 70S. THE WEATHER BEGINS TO IMPROVE BY TUESDAY...HOWEVER WITH NORTHWEST FLOW CONTINUING...COULD STILL SEE AN ISOLATED SHOWER/STORM DEVELOPING DURING THE HEAT OF THE DAY. BASED ON SCANT PRECIP COVERAGE ON RECENT MORE FAVORABLE DAYS...WILL CONTINUE WITH ONLY SLIGHT CHC POPS. BY WEDNESDAY...UPPER HEIGHTS BEGIN TO RISE...MARKING THE RETURN OF WARMER AND MORE HUMID CONDITIONS. BOTH NAM-WRF AND GFS DEVELOP WAA TYPE PRECIP WEDNESDAY AND WEDNESDAY NIGHT...AS A WEAK WAVE LIFTS NORTHEASTWARD THROUGH THE AREA. THINK BOTH MODELS ARE WAY OVERDONE WITH THEIR QPF FIELDS...PARTICULARLY THE NAM-WRF...SO HAVE OPTED TO KEEP THINGS DRY AT THIS TIME. WILL INCREASE THE CLOUD COVER ACROSS THE WESTERN CWA WEDNESDAY...BUT THINK ANY SHOWERS WILL STAY ALONG AND WEST OF THE MISSISSIPPI RIVER...MORE ALONG THE LINES OF THE 12Z GFS SOLUTION. LONG TERM...THURSDAY THROUGH SUNDAY THURSDAY APPEARS TO BE THE WARMEST DAY OF THE WEEK...AS UPPER HEIGHTS CONTINUE TO RISE AND NEXT APPROACHING SYSTEM REMAINS LARGELY WEST OF THE REGION. BASED ON LOW-LEVEL THERMAL PROFILES...TEMPS SHOULD RISE INTO THE LOWER 90S ACROSS THE CENTRAL AND EASTERN CWA. WILL BE A LITTLE COOLER ACROSS THE WEST...DUE TO INCREASED CLOUD COVER AND PRECIP CHANCES. WEAK COLD FRONT STILL PROGGED TO PUSH INTO NORTHWEST ILLINOIS THURSDAY AFTERNOON...BUT WITH UPPER SUPPORT TRACKING WELL TO THE NORTH INTO THE UPPER GREAT LAKES...AREAL COVERAGE OF PRECIP WILL REMAIN LOW. HAVE ADJUSTED POPS SLIGHTLY TO FEATURE A 30 PERCENT OF SHOWERS/STORMS IN THE PEORIA AND BLOOMINGTON AREAS...WITH DRY WEATHER FURTHER SOUTH. MODELS IN PRETTY GOOD SYNOPTIC AGREEMENT IN THE EXTENDED...WITH THE MAIN DIFFERENCES APPEARING IN THE MESOSCALE DETAILS. MODEL CONSENSUS DROPS FRONTAL BOUNDARY INTO CENTRAL ILLINOIS ON FRIDAY...THEN SLOWLY SHIFTS IT SOUTHWARD OVER THE WEEKEND. WILL CONTINUE WITH LOW POPS THROUGHOUT THE PERIOD...PERHAPS DRYING OUT BY SUNDAY. AM A LITTLE CONCERNED THAT MODELS MAY BE PUSHING THE BOUNDARY SOUTHWARD TOO AGGRESSIVELY...PARTICULARLY GIVEN THE STRENGTH OF THE BUILDING UPPER RIDGE ACROSS THE SOUTHERN CONUS. WILL WAIT AND SEE WHAT THE NEXT COUPLE OF RUNS LOOK LIKE BEFORE EXTENDING LOW POPS INTO SUNDAY. BARNES && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LINCOLN IL 631 PM CDT SUN JUN 3 2007 .DISCUSSION... ISSUED 209 PM CDT SUN JUN 3 2007 MAIN ISSUE WITH THIS FORECAST PACKAGE WILL BE LOW POPS OVER THE NEXT 24 TO 36 HOURS...AS UPPER LOW GRADUALLY OPENS UP AND MOVES AWAY FROM THE REGION. IN THE LONGER-TERM...EMPHASIS WILL BE ON EVOLVING UPPER AIR PATTERN...AND THE TIMING OF THE NEXT SYSTEM BY THE END OF THE WEEK. LATEST SURFACE CHART SHOWS LOW PRESSURE CENTERED OVER SOUTHEAST WISCONSIN...WITH WEAK FRONTAL BOUNDARY EXTENDING INTO WEST-CENTRAL INDIANA. FURTHER WEST...A WEAK TROUGH/WIND-SHIFT LINE IS EVIDENT ACROSS IOWA. ALOFT...STRONG RIDGE IS BUILDING ACROSS THE WESTERN CONUS...WHILE PERSISTENT LOW OVER THE UPPER MIDWEST IS FINALLY GETTING A NUDGE EASTWARD. SHORT TERM...TONIGHT THROUGH WEDNESDAY WIDELY SCATTERED SHOWERS/STORMS WILL CONTINUE THIS EVENING...BUT CONVECTION WILL QUICKLY FADE AWAY ONCE DAYTIME INSTABILITY IS LOST. BEST AREAL COVERAGE OF SHOWERS WILL BE ACROSS THE FAR NORTHERN KILX CWA...ALONG AND NORTH OF A CANTON TO MINONK LINE...AIDED BY APPROACHING SURFACE TROUGH. WILL GO WITH SCT/ISOLATED WORDING THIS EVENING ACROSS THE CENTRAL AND NORTHERN ZONES...WITH DRY CONDITIONS EXPECTED AFTER MIDNIGHT. WILL ONCE AGAIN SEE SCATTERED SHOWERS/STORMS POPPING UP ACROSS CENTRAL ILLINOIS ON MONDAY...AS UPPER SYSTEM SHIFTS INTO THE GREAT LAKES. BASED ON ORIENTATION OF UPPER COLD POOL...BEST AREAL COVERAGE OF PRECIP SHOULD BE ACROSS THE E/NE CWA. WILL AGAIN GO WITH SCT WORDING FOR MONDAY...WITH 50 POPS ACROSS THE E/NE TAPERING TO 30S ACROSS THE FAR W. WITH PLENTY OF CLOUD COVER AROUND...TEMPS WILL BE HELD DOWN. AFTERNOON HIGHS WILL ONLY BE IN THE LOWER TO MIDDLE 70S. THE WEATHER BEGINS TO IMPROVE BY TUESDAY...HOWEVER WITH NORTHWEST FLOW CONTINUING...COULD STILL SEE AN ISOLATED SHOWER/STORM DEVELOPING DURING THE HEAT OF THE DAY. BASED ON SCANT PRECIP COVERAGE ON RECENT MORE FAVORABLE DAYS...WILL CONTINUE WITH ONLY SLIGHT CHC POPS. BY WEDNESDAY...UPPER HEIGHTS BEGIN TO RISE...MARKING THE RETURN OF WARMER AND MORE HUMID CONDITIONS. BOTH NAM-WRF AND GFS DEVELOP WAA TYPE PRECIP WEDNESDAY AND WEDNESDAY NIGHT...AS A WEAK WAVE LIFTS NORTHEASTWARD THROUGH THE AREA. THINK BOTH MODELS ARE WAY OVERDONE WITH THEIR QPF FIELDS...PARTICULARLY THE NAM-WRF...SO HAVE OPTED TO KEEP THINGS DRY AT THIS TIME. WILL INCREASE THE CLOUD COVER ACROSS THE WESTERN CWA WEDNESDAY...BUT THINK ANY SHOWERS WILL STAY ALONG AND WEST OF THE MISSISSIPPI RIVER...MORE ALONG THE LINES OF THE 12Z GFS SOLUTION. LONG TERM...THURSDAY THROUGH SUNDAY THURSDAY APPEARS TO BE THE WARMEST DAY OF THE WEEK...AS UPPER HEIGHTS CONTINUE TO RISE AND NEXT APPROACHING SYSTEM REMAINS LARGELY WEST OF THE REGION. BASED ON LOW-LEVEL THERMAL PROFILES...TEMPS SHOULD RISE INTO THE LOWER 90S ACROSS THE CENTRAL AND EASTERN CWA. WILL BE A LITTLE COOLER ACROSS THE WEST...DUE TO INCREASED CLOUD COVER AND PRECIP CHANCES. WEAK COLD FRONT STILL PROGGED TO PUSH INTO NORTHWEST ILLINOIS THURSDAY AFTERNOON...BUT WITH UPPER SUPPORT TRACKING WELL TO THE NORTH INTO THE UPPER GREAT LAKES...AREAL COVERAGE OF PRECIP WILL REMAIN LOW. HAVE ADJUSTED POPS SLIGHTLY TO FEATURE A 30 PERCENT OF SHOWERS/STORMS IN THE PEORIA AND BLOOMINGTON AREAS...WITH DRY WEATHER FURTHER SOUTH. MODELS IN PRETTY GOOD SYNOPTIC AGREEMENT IN THE EXTENDED...WITH THE MAIN DIFFERENCES APPEARING IN THE MESOSCALE DETAILS. MODEL CONSENSUS DROPS FRONTAL BOUNDARY INTO CENTRAL ILLINOIS ON FRIDAY...THEN SLOWLY SHIFTS IT SOUTHWARD OVER THE WEEKEND. WILL CONTINUE WITH LOW POPS THROUGHOUT THE PERIOD...PERHAPS DRYING OUT BY SUNDAY. AM A LITTLE CONCERNED THAT MODELS MAY BE PUSHING THE BOUNDARY SOUTHWARD TOO AGGRESSIVELY...PARTICULARLY GIVEN THE STRENGTH OF THE BUILDING UPPER RIDGE ACROSS THE SOUTHERN CONUS. WILL WAIT AND SEE WHAT THE NEXT COUPLE OF RUNS LOOK LIKE BEFORE EXTENDING LOW POPS INTO SUNDAY. BARNES && .AVIATION... ISSUED 621 PM CDT SUN JUN 3 2007 FOR THE 00Z TAFS SHOWERS WILL CONTINUE THROUGH MID EVENING...WITH AN ISOLATED THUNDERSTORM ALSO POSSIBLE. INSTABILITY LOOKS FAVORABLE ENOUGH ON RUC SOUNDINGS TO KEEP A VCTS THROUGH 03-04Z. STORMS LINGERED A LITTLE LONGER THAN THAT LAST NIGHT...SO WILL KEEP AN EYE ON UPSTREAM DEVELOPMENT FOR POSSIBLE UPDATES. CIGS AND VIS READINGS SHOULD REMAIN VFR...WITH ONLY A VERY SHORT PERIOD OF MVFR POSSIBLE. NON OF THE SHOWERS OR STORMS WILL LAST LONG ENOUGH IN ONE PLACE TO WARRANT PUTTING IN ANY IFR CONDITIONS THIS EVENING. FOG SHOULD NOT BE A PROBLEM LATER TONIGHT...AS WINDS SHOULD INCREASE TOWARD MORNING. SHIMON && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 200 PM EDT SUN JUN 3 2007 .AVIATION... SEVERAL N-S ORIENTED LINES OF TSTMS HAVE DEVELOPED OVER NRN INDIANA EARLY THIS AFTN. ONE LINE CURRENTLY EXTENDING THROUGH FWA AND CONTG TO DVLP TO THE SOUTH SHOULD CONT TO AFFECT THE TERMINAL FOR THE NEXT 1-2HRS. VISIBLE STLT INDICATES A SMALL CLEAR SLOT WEST OF SBN WHICH SHOULD ALLOW FOR DESTABILIZATION FOR FURTHER DEVELOPMENT WHICH WILL AFFECT SBN THIS AFTN. CDFNT OVER ERN IL SHOULD MOVE ACROSS NRN INDIANA THIS EVE, SHIFTING WINDS TO WEST AND DECREASING CONVECTION. SECONDARY CDFNT WILL DROP SE ACROSS THE AREA ON MONDAY RESULTING IN WIND SHIFT TO NW WITH MORE SHOWERS AND TSTMS EXPECTED AS THIS MOVES THROUGH. THIS SHOULD TAKE PLACE VERY LATE IN THE TAF PERIOD OR MORE LIKELY JUST BEYOND, SO NO MENTION IN TAFS ATTM. && .SHORT TERM... TODAY AND TONIGHT MAIN FORECAST CHALLENGES WILL BE FORECAST HIGH TEMPS TODAY AND INTENSITY OF CONVECTION TODAY. OTHERWISE...FORECAST PRETTY MUCH ON TRACK PRECIP WISE...GIVEN AMPLE FORCING AVAILABLE FROM H5 VORTEX. CURRENT ANALYSIS REVEALS 20 TO 30 KNOT LL JET IN PLACE ACROSS WESTERN IN/EASTERN IL PER VWP/PROFILER/RUC ANALYSIS. THIS FEATURE COUPLED WITH RESIDUAL MID LEVEL WAVE HAS ALLOWED SHOWER/THUNDERSTORM DEVELOPMENT. WEAK INSTABILITY HAS LIMITED CONVECTIVE INTENSITY...WITH MAJORITY OF PRECIP IN THE FORM OF LIGHT TO MODERATE SHOWERS. THIS AREA OF PRECIP IS PROGGED TO CONTINUE NORTHEASTWARD INTO WESTERN ZONES THROUGH LATE MORNING. SHOULD SEE A DIMINISHING TREND AS LL JET WEAKENS AFTER SUNRISE. OTHERWISE...TEMPS WERE MAINLY IN THE UPPER 60S ACROSS THE FA WITH LIGHT TO CALM WINDS. PRECIP FOCUS WILL SHIFT TO SFC COLD FRONT THIS AFTERNOON. WRF AND GFS BOTH INDICATE GOOD CONVERGENCE ALONG AND AHEAD OF COLD FRONT THIS AFTERNOON. MEANWHILE BROAD LIFT FROM H5 VORTEX WILL INCREASE POTENTIAL INSTABILITY WITH AMPLE MID LEVEL DRY IN PLACE UPSTREAM GIVEN 00Z DVN SOUNDING. BIG QUESTION MARK WILL BE HOW MUCH DAYTIME HEATING WILL BE SEEN ACROSS FA BEFORE GOOD DYNAMICS FALL IN PLACE. SUNSHINE MAY BE LACKING TODAY DUE TO RESIDUAL CLOUD COVER FROM CURRENT UPSTREAM CONVECTION. THIS WILL ALSO HAVE AN IMPACT ON HIGHS TODAY. HAVE TRENDED TOWARD COOLER SOLUTION IN FORECAST...GIVEN WIDESPREAD CLOUD COVER IN PLACE. HOWEVER...IF SUNSHINE DOES BREAK OUT...SFC BASED CAPE VALUES WOULD EASILY CLIMB TO AOR 1500 J/KG. DEEP SHEAR WILL ALSO BE ON THE INCREASE AS ASSOCIATED UPPER JET STREAK ADVECTS INTO THE REGION...PRODUCING DEEP SHEAR VALUES AROUND 30-35 KNOTS...ESPECIALLY IN WESTERN ZONES. BOTTOM LINE...IF GOOD HEATING DOES OCCUR...SEVERE THREAT WOULD BE ELEVATED. HOWEVER...NOT THINKING ANYTHING WIDESPREAD. MAIN THREATS WOULD BE DAMAGING WIND AND LARGE HAIL. AGAIN HIGHS TODAY WILL BE STRONGLY DEPENDENT ON CLOUD COVER. CURRENT TEMPS IN GRIDS REFLECT PARTIAL CLEARING. TEMPS COULD EASILY SWAY 5-7 DEGREES EITHER WAY DEPENDING ON AMOUNT OF ISOLATION. RAIN SHOWER/ISOLATED THUNDER CHANCES WILL CONTINUE TONIGHT...ESPECIALLY IN NORTHERN PORTIONS OF FA. DRY SLOT WITH SUBSIDENCE BEHIND LEAD WAVE MAY CLEAR OUT SOUTHERN ZONES...HENCE HAVE LEFT LOWER POPS THERE. COOLER AIR WILL MOVE INTO THE FA TONIGHT. AMPLE LL MOISTURE IN PLACE WITH EXPECTED RAIN COMBINED WITH THIS COOLER AIR MAY LEAD TO AREAS OF FOG. HAVE NOT WORDED IN FORECAST YET...AS THERE IS QUESTIONS ON AMOUNT OF CLOUD COVER. .LONG TERM... MONDAY THROUGH SATURDAY UPPER LOW STILL EXPECTED TO DRIFT INTO OUR AREA BY MONDAY BEFORE OPENING UP AND LIFTING OUT ON TUESDAY. DECENT MID LEVEL LAPSE RATES UNDER CIRCULATION MONDAY WITH LOW LEVEL MOISTURE AND WEAK SHORT WAVES SHOULD LEAD TO SHOWER AND THUNDERSTORM DEVELOPMENT DURING THE DAY. BUMPED POPS INTO LIKELY CATEGORY. MODELS LINGER MOISTURE WITH SURFACE FRONT INTO MONDAY NIGHT SO HIGH CHANCE POPS THROUGH THIS PERIOD. LOW BEGINS TO EXIT ON TUE WITH SOME LINGERING MOISTURE ON BACK SIDE. PREVIOUS SHIFT ADDED POPS FOR TUE SO WILL CONTINUE THOUGH DRYING WORKING IN QUICKLY. MODELS MAY STILL BE A TAD FAST LIFTING LOW OUT. TEMPERATURES COOLER THROUGH THIS PERIOD AS WELL. CUT TEMPS SEVERAL DEGREES ON MONDAY...ESPECIALLY NORTHWEST WITH UPPER LOW OVER AREA AND FLOW INCREASING OFF OF COOLER LAKE MICHIGAN. NAM12 2M TEMPS STRUGGLE TO EVEN GET OUT OF THE 50S. HAVE DROPPED TO MID 60S CLOSER TO COOLER MOS FOR NOW. WILL ALSO MENTION RIP CURRENTS FOR LAKE MICHIGAN IN HWO FOR THIS PERIOD WITH RATHER STRONG NORTHWEST WINDS EXPECTED TO DEVELOP AND INCREASING WAVES. HIGH PRESSURE SETTLES OVER THE AREA FOR WED BEFORE RETURN FLOW QUICKLY SETS UP AND WARM FRONT MOVES THROUGH WED NIGHT. KEPT THIS PERIOD DRY FOR NOW AS MODELS INDICATE LIMITED MOISTURE. HOWEVER...WITH SUCH A STRONG FRONT AND TIGHTENING BAROCLINIC ZONE...WOULD EXPECT SOME PCPN TO DEVELOP ON NOSE OF INCREASING LOW LEVEL JET. BEST FOCUS CURRENTLY LOOKS TO BE TO OUR NORTHWEST BUT WILL MONITOR. THURSDAY STILL LOOKING VERY WARM AND CONTINUED TO STAY ABOVE MEX MOS AND RAISED TEMPS A FEW MORE DEGREES. ECMWF VERY WARM WITH +20C AT 850MB. HAVE DOUBTS AS TO THUNDERSTORM CHANCES GIVEN VERY WARM AIR ALOFT AND LACK OF TRIGGER TIL LATER IN THE DAY OR THU NIGHT WITH POSSIBLE APPROACH OF COLD FRONT. MODELS VARY IN TIMING AND GENERAL SOLUTIONS SO NO CHANGES AT THIS TIME. UNCERTAINTY CONTINUES REMAINDER OF EXTENDED WITH MODELS DIFFERING ON FRONTAL POSITION AND MOVEMENT SO NO CHANGES. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ AVIATION...JT/LF SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 642 AM EDT SUN JUN 3 2007 .AVIATION... LINE OF TSRA MOVING NORTH NORTHEAST AND EXITING IMMEDIATE KSBN AREA AT ISSUANCE. WATCHING REDEVELOPMENT NEAR MONTICELLO AND ROCHESTER THAT WILL MOVE NORTH AND BACK INTO KSBN IN A FEW HOURS. KFWA QUIET FOR NOW BUT EXPECT ADDITIONAL TSRA DEVELOPMENT TODAY IN UNSTABLE ATMOSPHERE...ESPECIALLY IF BREAKS IN CLOUD COVER OCCUR. HAVE KEPT A VCSH OR VCTS IN TAFS MOST OF DAY. WENT OPTIMISTIC OVERNIGHT WITH NO MENTION BUT WILL HAVE TO MONITOR AFTERNOON TRENDS FOR POSSIBLE INCLUSION OF SHRA OR TSRA THIS EVENING. ALSO KEPT BR OUT OF TAFS FOR TONIGHT WITH EXPECTED MID LEVEL CLOUD DECK. IF CLEARING OCCURS...FOG WILL BE POSSIBLE OVERNIGHT. && .SHORT TERM... TODAY AND TONIGHT MAIN FORECAST CHALLENGES WILL BE FORECAST HIGH TEMPS TODAY AND INTENSITY OF CONVECTION TODAY. OTHERWISE...FORECAST PRETTY MUCH ON TRACK PRECIP WISE...GIVEN AMPLE FORCING AVAILABLE FROM H5 VORTEX. CURRENT ANALYSIS REVEALS 20 TO 30 KNOT LL JET IN PLACE ACROSS WESTERN IN/EASTERN IL PER VWP/PROFILER/RUC ANALYSIS. THIS FEATURE COUPLED WITH RESIDUAL MID LEVEL WAVE HAS ALLOWED SHOWER/THUNDERSTORM DEVELOPMENT. WEAK INSTABILITY HAS LIMITED CONVECTIVE INTENSITY...WITH MAJORITY OF PRECIP IN THE FORM OF LIGHT TO MODERATE SHOWERS. THIS AREA OF PRECIP IS PROGGED TO CONTINUE NORTHEASTWARD INTO WESTERN ZONES THROUGH LATE MORNING. SHOULD SEE A DIMINISHING TREND AS LL JET WEAKENS AFTER SUNRISE. OTHERWISE...TEMPS WERE MAINLY IN THE UPPER 60S ACROSS THE FA WITH LIGHT TO CALM WINDS. PRECIP FOCUS WILL SHIFT TO SFC COLD FRONT THIS AFTERNOON. WRF AND GFS BOTH INDICATE GOOD CONVERGENCE ALONG AND AHEAD OF COLD FRONT THIS AFTERNOON. MEANWHILE BROAD LIFT FROM H5 VORTEX WILL INCREASE POTENTIAL INSTABILITY WITH AMPLE MID LEVEL DRY IN PLACE UPSTREAM GIVEN 00Z DVN SOUNDING. BIG QUESTION MARK WILL BE HOW MUCH DAYTIME HEATING WILL BE SEEN ACROSS FA BEFORE GOOD DYNAMICS FALL IN PLACE. SUNSHINE MAY BE LACKING TODAY DUE TO RESIDUAL CLOUD COVER FROM CURRENT UPSTREAM CONVECTION. THIS WILL ALSO HAVE AN IMPACT ON HIGHS TODAY. HAVE TRENDED TOWARD COOLER SOLUTION IN FORECAST...GIVEN WIDESPREAD CLOUD COVER IN PLACE. HOWEVER...IF SUNSHINE DOES BREAK OUT...SFC BASED CAPE VALUES WOULD EASILY CLIMB TO AOR 1500 J/KG. DEEP SHEAR WILL ALSO BE ON THE INCREASE AS ASSOCIATED UPPER JET STREAK ADVECTS INTO THE REGION...PRODUCING DEEP SHEAR VALUES AROUND 30-35 KNOTS...ESPECIALLY IN WESTERN ZONES. BOTTOM LINE...IF GOOD HEATING DOES OCCUR...SEVERE THREAT WOULD BE ELEVATED. HOWEVER...NOT THINKING ANYTHING WIDESPREAD. MAIN THREATS WOULD BE DAMAGING WIND AND LARGE HAIL. AGAIN HIGHS TODAY WILL BE STRONGLY DEPENDENT ON CLOUD COVER. CURRENT TEMPS IN GRIDS REFLECT PARTIAL CLEARING. TEMPS COULD EASILY SWAY 5-7 DEGREES EITHER WAY DEPENDING ON AMOUNT OF ISOLATION. RAIN SHOWER/ISOLATED THUNDER CHANCES WILL CONTINUE TONIGHT...ESPECIALLY IN NORTHERN PORTIONS OF FA. DRY SLOT WITH SUBSIDENCE BEHIND LEAD WAVE MAY CLEAR OUT SOUTHERN ZONES...HENCE HAVE LEFT LOWER POPS THERE. COOLER AIR WILL MOVE INTO THE FA TONIGHT. AMPLE LL MOISTURE IN PLACE WITH EXPECTED RAIN COMBINED WITH THIS COOLER AIR MAY LEAD TO AREAS OF FOG. HAVE NOT WORDED IN FORECAST YET...AS THERE IS QUESTIONS ON AMOUNT OF CLOUD COVER. .LONG TERM... MONDAY THROUGH SATURDAY UPPER LOW STILL EXPECTED TO DRIFT INTO OUR AREA BY MONDAY BEFORE OPENING UP AND LIFTING OUT ON TUESDAY. DECENT MID LEVEL LAPSE RATES UNDER CIRCULATION MONDAY WITH LOW LEVEL MOISTURE AND WEAK SHORT WAVES SHOULD LEAD TO SHOWER AND THUNDERSTORM DEVELOPMENT DURING THE DAY. BUMPED POPS INTO LIKELY CATEGORY. MODELS LINGER MOISTURE WITH SURFACE FRONT INTO MONDAY NIGHT SO HIGH CHANCE POPS THROUGH THIS PERIOD. LOW BEGINS TO EXIT ON TUE WITH SOME LINGERING MOISTURE ON BACK SIDE. PREVIOUS SHIFT ADDED POPS FOR TUE SO WILL CONTINUE THOUGH DRYING WORKING IN QUICKLY. MODELS MAY STILL BE A TAD FAST LIFTING LOW OUT. TEMPERATURES COOLER THROUGH THIS PERIOD AS WELL. CUT TEMPS SEVERAL DEGREES ON MONDAY...ESPECIALLY NORTHWEST WITH UPPER LOW OVER AREA AND FLOW INCREASING OFF OF COOLER LAKE MICHIGAN. NAM12 2M TEMPS STRUGGLE TO EVEN GET OUT OF THE 50S. HAVE DROPPED TO MID 60S CLOSER TO COOLER MOS FOR NOW. WILL ALSO MENTION RIP CURRENTS FOR LAKE MICHIGAN IN HWO FOR THIS PERIOD WITH RATHER STRONG NORTHWEST WINDS EXPECTED TO DEVELOP AND INCREASING WAVES. HIGH PRESSURE SETTLES OVER THE AREA FOR WED BEFORE RETURN FLOW QUICKLY SETS UP AND WARM FRONT MOVES THROUGH WED NIGHT. KEPT THIS PERIOD DRY FOR NOW AS MODELS INDICATE LIMITED MOISTURE. HOWEVER...WITH SUCH A STRONG FRONT AND TIGHTENING BAROCLINIC ZONE...WOULD EXPECT SOME PCPN TO DEVELOP ON NOSE OF INCREASING LOW LEVEL JET. BEST FOCUS CURRENTLY LOOKS TO BE TO OUR NORTHWEST BUT WILL MONITOR. THURSDAY STILL LOOKING VERY WARM AND CONTINUED TO STAY ABOVE MEX MOS AND RAISED TEMPS A FEW MORE DEGREES. ECMWF VERY WARM WITH +20C AT 850MB. HAVE DOUBTS AS TO THUNDERSTORM CHANCES GIVEN VERY WARM AIR ALOFT AND LACK OF TRIGGER TIL LATER IN THE DAY OR THU NIGHT WITH POSSIBLE APPROACH OF COLD FRONT. MODELS VARY IN TIMING AND GENERAL SOLUTIONS SO NO CHANGES AT THIS TIME. UNCERTAINTY CONTINUES REMAINDER OF EXTENDED WITH MODELS DIFFERING ON FRONTAL POSITION AND MOVEMENT SO NO CHANGES. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ AVIATION...CHAMBERLAIN/LASHLEY SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 324 AM EDT SUN JUN 3 2007 .SHORT TERM... TODAY AND TONIGHT MAIN FORECAST CHALLENGES WILL BE FORECAST HIGH TEMPS TODAY AND INTENSITY OF CONVECTION TODAY. OTHERWISE...FORECAST PRETTY MUCH ON TRACK PRECIP WISE...GIVEN AMPLE FORCING AVAILABLE FROM H5 VORTEX. CURRENT ANALYSIS REVEALS 20 TO 30 KNOT LL JET IN PLACE ACROSS WESTERN IN/EASTERN IL PER VWP/PROFILER/RUC ANALYSIS. THIS FEATURE COUPLED WITH RESIDUAL MID LEVEL WAVE HAS ALLOWED SHOWER/THUNDERSTORM DEVELOPMENT. WEAK INSTABILITY HAS LIMITED CONVECTIVE INTENSITY...WITH MAJORITY OF PRECIP IN THE FORM OF LIGHT TO MODERATE SHOWERS. THIS AREA OF PRECIP IS PROGGED TO CONTINUE NORTHEASTWARD INTO WESTERN ZONES THROUGH LATE MORNING. SHOULD SEE A DIMINISHING TREND AS LL JET WEAKENS AFTER SUNRISE. OTHERWISE...TEMPS WERE MAINLY IN THE UPPER 60S ACROSS THE FA WITH LIGHT TO CALM WINDS. PRECIP FOCUS WILL SHIFT TO SFC COLD FRONT THIS AFTERNOON. WRF AND GFS BOTH INDICATE GOOD CONVERGENCE ALONG AND AHEAD OF COLD FRONT THIS AFTERNOON. MEANWHILE BROAD LIFT FROM H5 VORTEX WILL INCREASE POTENTIAL INSTABILITY WITH AMPLE MID LEVEL DRY IN PLACE UPSTREAM GIVEN 00Z DVN SOUNDING. BIG QUESTION MARK WILL BE HOW MUCH DAYTIME HEATING WILL BE SEEN ACROSS FA BEFORE GOOD DYNAMICS FALL IN PLACE. SUNSHINE MAY BE LACKING TODAY DUE TO RESIDUAL CLOUD COVER FROM CURRENT UPSTREAM CONVECTION. THIS WILL ALSO HAVE AN IMPACT ON HIGHS TODAY. HAVE TRENDED TOWARD COOLER SOLUTION IN FORECAST...GIVEN WIDESPREAD CLOUD COVER IN PLACE. HOWEVER...IF SUNSHINE DOES BREAK OUT...SFC BASED CAPE VALUES WOULD EASILY CLIMB TO AOR 1500 J/KG. DEEP SHEAR WILL ALSO BE ON THE INCREASE AS ASSOCIATED UPPER JET STREAK ADVECTS INTO THE REGION...PRODUCING DEEP SHEAR VALUES AROUND 30-35 KNOTS...ESPECIALLY IN WESTERN ZONES. BOTTOM LINE...IF GOOD HEATING DOES OCCUR...SEVERE THREAT WOULD BE ELEVATED. HOWEVER...NOT THINKING ANYTHING WIDESPREAD. MAIN THREATS WOULD BE DAMAGING WIND AND LARGE HAIL. AGAIN HIGHS TODAY WILL BE STRONGLY DEPENDENT ON CLOUD COVER. CURRENT TEMPS IN GRIDS REFLECT PARTIAL CLEARING. TEMPS COULD EASILY SWAY 5-7 DEGREES EITHER WAY DEPENDING ON AMOUNT OF ISOLATION. RAIN SHOWER/ISOLATED THUNDER CHANCES WILL CONTINUE TONIGHT...ESPECIALLY IN NORTHERN PORTIONS OF FA. DRY SLOT WITH SUBSIDENCE BEHIND LEAD WAVE MAY CLEAR OUT SOUTHERN ZONES...HENCE HAVE LEFT LOWER POPS THERE. COOLER AIR WILL MOVE INTO THE FA TONIGHT. AMPLE LL MOISTURE IN PLACE WITH EXPECTED RAIN COMBINED WITH THIS COOLER AIR MAY LEAD TO AREAS OF FOG. HAVE NOT WORDED IN FORECAST YET...AS THERE IS QUESTIONS ON AMOUNT OF CLOUD COVER. .LONG TERM... MONDAY THROUGH SATURDAY UPPER LOW STILL EXPECTED TO DRIFT INTO OUR AREA BY MONDAY BEFORE OPENING UP AND LIFTING OUT ON TUESDAY. DECENT MID LEVEL LAPSE RATES UNDER CIRCULATION MONDAY WITH LOW LEVEL MOISTURE AND WEAK SHORT WAVES SHOULD LEAD TO SHOWER AND THUNDERSTORM DEVELOPMENT DURING THE DAY. BUMPED POPS INTO LIKELY CATEGORY. MODELS LINGER MOISTURE WITH SURFACE FRONT INTO MONDAY NIGHT SO HIGH CHANCE POPS THROUGH THIS PERIOD. LOW BEGINS TO EXIT ON TUE WITH SOME LINGERING MOISTURE ON BACK SIDE. PREVIOUS SHIFT ADDED POPS FOR TUE SO WILL CONTINUE THOUGH DRYING WORKING IN QUICKLY. MODELS MAY STILL BE A TAD FAST LIFTING LOW OUT. TEMPERATURES COOLER THROUGH THIS PERIOD AS WELL. CUT TEMPS SEVERAL DEGREES ON MONDAY...ESPECIALLY NORTHWEST WITH UPPER LOW OVER AREA AND FLOW INCREASING OFF OF COOLER LAKE MICHIGAN. NAM12 2M TEMPS STRUGGLE TO EVEN GET OUT OF THE 50S. HAVE DROPPED TO MID 60S CLOSER TO COOLER MOS FOR NOW. WILL ALSO MENTION RIP CURRENTS FOR LAKE MICHIGAN IN HWO FOR THIS PERIOD WITH RATHER STRONG NORTHWEST WINDS EXPECTED TO DEVELOP AND INCREASING WAVES. HIGH PRESSURE SETTLES OVER THE AREA FOR WED BEFORE RETURN FLOW QUICKLY SETS UP AND WARM FRONT MOVES THROUGH WED NIGHT. KEPT THIS PERIOD DRY FOR NOW AS MODELS INDICATE LIMITED MOISTURE. HOWEVER...WITH SUCH A STRONG FRONT AND TIGHTENING BAROCLINIC ZONE...WOULD EXPECT SOME PCPN TO DEVELOP ON NOSE OF INCREASING LOW LEVEL JET. BEST FOCUS CURRENTLY LOOKS TO BE TO OUR NORTHWEST BUT WILL MONITOR. THURSDAY STILL LOOKING VERY WARM AND CONTINUED TO STAY ABOVE MEX MOS AND RAISED TEMPS A FEW MORE DEGREES. ECMWF VERY WARM WITH +20C AT 850MB. HAVE DOUBTS AS TO THUNDERSTORM CHANCES GIVEN VERY WARM AIR ALOFT AND LACK OF TRIGGER TIL LATER IN THE DAY OR THU NIGHT WITH POSSIBLE APPROACH OF COLD FRONT. MODELS VARY IN TIMING AND GENERAL SOLUTIONS SO NO CHANGES AT THIS TIME. UNCERTAINTY CONTINUES REMAINDER OF EXTENDED WITH MODELS DIFFERING ON FRONTAL POSITION AND MOVEMENT SO NO CHANGES. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 150 PM EDT SAT JUN 2 2007 .AVIATION... STORMS INCREASING IN COVERAGE EAST OF KFWA AT THIS TIME. FEW SML ISOL CELLS MOVING NEAR THE AIRPORT BUT EXPECTING COVERAGE TO INCREASE. HAVE WENT WITH A TEMPO SHOWER FOR A FEW HOURS AT KFWA TO COVER THIS DEVELOPMENT AND THEN EXPANDED THROUGH 23Z TO COVER INCREASING COVERAGE WITH STATIONARY BOUNDARY SE OF KFWA THAT WAS RESPONSIBLE FOR ACTIVITY YESTERDAY. TOWARDS KSBN BOUNDARY WORKING RAPIDLY NE ACROSS NW INDIANA FIRING CONVECTION NOW BUT MAINLY LOOKS TO PASS NW OF KSBN. ADDITIONAL ACTIVITY MAY DEVELOP IN THIS AREA COURTESY OF LAKE BREEZE BUT SFC OBS SHOWING SOUTHERN EXTENT OF LAKE BREEZE HAVING A HARD TIME REACHING INLAND WITH WINDS SHIFTING WEST THEN BACK TO SW. HAVE OPTED TO LEAVE ANY PRECIP OUT OF KSBN FOR THE MOMENT UNTIL EFFECTS OF LAKE BREEZE CAN BE DETERMINED. OTHERWISE KSBN MAY HAVE TO WAIT TILL TONIGHT FOR ANY PRECIP. && .UPDATE... CLOSELY MONITORING CONDITIONS IN NW QUARTER TO HALF OF CWA AS STG SFC HEATING AND DEWPTS IN THE MID 60S AND SFC TEMPS IN THE UPPER 70S TO AROUND 80 ALREADY LENDING TO SB CAPES AOA 2000 J/KG AND LI/S -3 TO -6 C PER SPC MESO ANALYSIS PAGE AT 14Z. MESO PAGE ALSO SHOWS MUCH OF THE CIN NOW GONE. MUCH OF THE FOCUS IS ALONG THE LAKE WHERE CONVERGENCE HAS ALLOWED FOR POOLING OF BETTER MSTR WITH A FEW LOCATIONS PUSHING 70 FOR DEWPTS. THIS WILL SET THE STAGE FOR THE POTENTIAL OF RAPID CONVECTIVE DEVELOPMENT AS THE LAKE BREEZE TAKES SHAPE OVER THE NEXT SEVERAL HOURS. IN ADDITION...REMNANTS OF MCV IN MISSOURI PROGGED TO MOVE INTO THE WESTERN PARTS OF THE AREA AFTER 16Z. ONE OTHER POINT IS A FAST MOVING BOUNDARY WAS NOTED ON KIWX BASE DATA THAT NOW RESIDES IN NE PARTS OF THE AREA. STORMS WILL LIKELY BE ISOL-SCT IN NATURE AND OF PULSE VARIETY AT THE START AS BEST SHEAR REMAINS JUST TO THE WEST. HOWEVER AS AFTERNOON WEARS ON AND EVE APPROACHES COMBINATION OF INCREASING SHEAR AND LIKELY EXISTENCE OF SEVERAL BOUNDARIES AROUND THE AREA...SVR THREAT SHOULD INCREASE...ESPECIALLY NW AREAS. WILL HOLD OFF ON SVR MENTION IN ZONES FOR NOW. LOOK OUT THE WINDOW NOW SHOWS CU POPPING SO CONVECTIVE TEMP IN LOW 80S AS PROGGED. HAVE MOVED UP TIMING A BIT ON LIKELY POPS. HAD THOUGHT ABOUT TRENDING WITH SCT POPS NW TO NUMEROUS BUT WOULD LIKE TO SEE HOW THINGS EVOLVE BEFORE GETTING LOCKED INTO SPECIFIC WORDING WITH MID LEVEL CAPPING STILL SHOWING UP ON 12Z SOUNDINGS THAT COULD SLOW DOWN DEVELOPMENT UNTIL MCV AND BETTER DYNAMICS APPROACHES LATER TODAY. TEMPS ON TRACK. CHANGED SKY COVER TO REFLECT MORE SUN EARLY WITH INCREASING CLOUDS NW AREAS FIRST TRENDING EVERYWHERE BY LATE AFTN. && .PREV DISCUSSION... SHORT TERM... TODAY AND TONIGHT INTERESTING WEATHER SETUP TODAY WITH PLENTY OF CHALLENGES IN STORE FOR TODAYS FORECAST. CURRENT ANALYSIS REVEALS WEAKENING PROGRESSING SPEED MAX PROPAGATING THROUGH LOWER WESTERN MI. A BROKEN LINE OF THUNDERSTORMS EXTENDED SOUTH FROM BALDWIN MI TO SOUTH BEND IN. THIS LINE OF STORMS WAA BEING SUPPORTED BY WEAK THETA E ADVECTION UNDER SEMI-STEEP LAPSE RATES. OTHER ISOLATED CONVECTION WAS TRYING TO DEVELOP IN CENTRAL IL...WHERE LL JET WAS ESTABLISHED...AS INDICATED BY 40 KNOT H85 WIND SPEED ON ILX VWP. FURTHER UPSTREAM...A LARGE AREA OF WEAKENING SHOWERS/THUNDERSTORMS WAS ADVANCING SLOWLY NORTHEAST THROUGH CENTRAL MO. RUC HINTS AT A VORT MAX AT 700MB...AND WITH PREVIOUS INTENSITY OF CONVECTIVE SYSTEM...MCV DEVELOPMENT IS LIKELY IN FULL SWING. THIS WILL LIKELY HAVE A LARGE IMPACT OF PRECIP DEVELOPMENT THIS AFTERNOON. EXPECTING CONVECTION TO DIMINISH ACROSS NORTHWESTERN ZONES THIS MORNING. H5 SPEED MAX ALONG WITH ASSOCIATED LL JET WILL WEAKEN AND PUSH OUT OF THE REGION. HOWEVER...CANNOT RULE OUT ISOLATED THUNDER THREAT INTO MID MORNING GIVEN DEGREE OF INSTABILITY IN PLACE..COUPLED WITH SECONDARY LL SPEED MAX ACROSS CENTRAL IL. FOCUS WILL SHIFT TO DEVELOPING MCV UPSTREAM IN MO. THIS IMPULSE IS PROGGED TO PUSH NORTHEAST INTO FA BY EARLY AFTERNOON WHEN DIURNAL EFFECTS WILL COME INTO PLAY...ALTHOUGH MID CLOUD SHIELD MAY INHIBIT ROBUST HEATING ACROSS WESTERN ZONES. MODELS ALSO SIGNIFICANTLY WEAKEN MCV AS IT LIFTS NORTHEAST INTO FA. HOWEVER...MCV SYSTEMS ARE NOTORIOUSLY POORLY HANDLED BY FORECAST MODELS AND GIVEN THE NUMEROUS LL BOUNDARIES IN PLACE PER RADAR ANALYSIS WITH DEEP MOISTURE CONTINUOUSLY BUILDING INTO THE REGION...HAVE RAISED POPS TO LIKELY ACROSS THE FA FOR ANTICIPATED THUNDERSTORM DEVELOPMENT. SEVERE THREAT IS CERTAINLY POSSIBLE ACROSS FA. WRF INDICATES FAIR AMOUNT OF DRY AIR AT MID LEVELS THIS AFTERNOON. THIS COUPLED WITH STEEP MID LEVEL LAPSE RATES...NEAR INVERTED V SOUNDINGS AND CAPE VALUES AOA 2000 J/KG...ATM WOULD SUPPORT A FEW SEVERE STORMS WITH DAMAGING WIND BEING THE MAIN THREAT. MAIN H5 VORTEX OVER THE NORTHERN PLAINS AND ASSOCIATED SPEED MAX WILL SLOWLY MOVE EAST INTO THE REGION. BEST COMBINATION OF DEEP SHEAR AND LOW LEVEL FORCING SHOULD REMAIN WEST OF FA UNTIL LATE EVENING. THIS SHOULD LIMIT A WIDESPREAD SEVERE RISK OVER FA. THINKING STORMS ACROSS FA WILL MOST LIKELY ORGANIZE INTO A LINE OR LINES AND PUSH NORTHEAST...WITH AMPLE INSTABILITY AND 0-3KM SHEAR IN PLACE. HEAVY RAINFALL WILL BE POSSIBLE WITH ANY THUNDERSTORMS THAT DO DEVELOP GIVEN PRECIP WATER VALUES IN THE 1.5 TO 2 INCH RANGE. PERSISTENT NORTHERN PLAINS UPPER LOW AND ASSOCIATED SFC COLD FRONT WILL PUSH EAST INTO THE GREAT LAKES TONIGHT AND ALLOW SHOWER/THUNDERSTORM CHANCES THROUGH THE NIGHT. OTHERWISE...LOOK FOR ANOTHER WARM DAY ACROSS THE FA WITH THE WARMEST TEMPS IN THE EASTERN ZONES...WHERE TEMPS AROUND 90 ARE POSSIBLE. COOLER H85 TEMPS AND CLOUD COVER SHOULD QUELL EXTREME TEMP RISES ACROSS WESTERN ZONES. LONG TERM... SUNDAY THROUGH FRIDAY COMPLICATED FORECAST WITH REGARD TO DETAILS AND TIMING OF WAVES AND PRECIPITATION THROUGH EARLY PART OF NEXT WEEK. GENERALLY MADE FEW CHANGES TO WEATHER AND POP GRIDS...THOUGH DID TRY AND REFINE A BIT FOR COLLABORATION. UPPER LOW WILL SLOWLY DRIFT EAST INTO THE GREAT LAKES REGION THROUGH EARLY NEXT WEEK. COMPLICATION IN THE FORECAST COMES WITH NORTHWARD MOVEMENT OF TROPICAL SYSTEM THROUGH THE EASTERN CONUS. THIS SLOWS APPROACHING UPPER LOW EVEN MORE. STRONG WAVE AND ASSOCIATED SURFACE FRONT TO BE MOVING THROUGH AT BEGINNING OF THE LONG TERM PERIOD. KEPT LIKELY POPS GOING OVER EASTERN HALF OF THE FORECAST AREA SUNDAY. CONCERNED ABOUT DRY SLOT MOVING IN BUT NOT GOING TO TRY AND TIME THIS UNCERTAINTY AT THIS TIME. UPPER LOW REMAINS ACROSS THE AREA THROUGH MONDAY WITH PCPN CHANCES LINGERING. FIRST PART OF THE WEEK WILL BE COOLER BEHIND DEPARTING LOW AND NORTHERLY FLOW. LATEST MODELS INDICATING THIS COOL STRETCH WILL BE SHORT LIVED AS WARM FRONT DEVELOPS AND MOVES NORTH MID WEEK WITH A RETURN TO VERY WARM AIR POSSIBLE BY THURSDAY. HAVE RAISED HIGHS SEVERAL DEGREES FOR THIS AS ECMWF AND GFS IN AGREEMENT. EXPECT MAX TEMPS BY THU WILL BE CLOSER TO 90 BUT WILL TREND IN THAT DIRECTION AND MONITOR ADDITIONAL MODEL RUNS. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE/AVIATION...FISHER SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 1106 AM EDT SAT JUN 2 2007 .UPDATE... CLOSELY MONITORING CONDITIONS IN NW QUARTER TO HALF OF CWA AS STG SFC HEATING AND DEWPTS IN THE MID 60S AND SFC TEMPS IN THE UPPER 70S TO AROUND 80 ALREADY LENDING TO SB CAPES AOA 2000 J/KG AND LI/S -3 TO -6 C PER SPC MESO ANALYSIS PAGE AT 14Z. MESO PAGE ALSO SHOWS MUCH OF THE CIN NOW GONE. MUCH OF THE FOCUS IS ALONG THE LAKE WHERE CONVERGENCE HAS ALLOWED FOR POOLING OF BETTER MSTR WITH A FEW LOCATIONS PUSHING 70 FOR DEWPTS. THIS WILL SET THE STAGE FOR THE POTENTIAL OF RAPID CONVECTIVE DEVELOPMENT AS THE LAKE BREEZE TAKES SHAPE OVER THE NEXT SEVERAL HOURS. IN ADDITION...REMNANTS OF MCV IN MISSOURI PROGGED TO MOVE INTO THE WESTERN PARTS OF THE AREA AFTER 16Z. ONE OTHER POINT IS A FAST MOVING BOUNDARY WAS NOTED ON KIWX BASE DATA THAT NOW RESIDES IN NE PARTS OF THE AREA. STORMS WILL LIKELY BE ISOL-SCT IN NATURE AND OF PULSE VARIETY AT THE START AS BEST SHEAR REMAINS JUST TO THE WEST. HOWEVER AS AFTERNOON WEARS ON AND EVE APPROACHES COMBINATION OF INCREASING SHEAR AND LIKELY EXISTENCE OF SEVERAL BOUNDARIES AROUND THE AREA...SVR THREAT SHOULD INCREASE...ESPECIALLY NW AREAS. WILL HOLD OFF ON SVR MENTION IN ZONES FOR NOW. LOOK OUT THE WINDOW NOW SHOWS CU POPPING SO CONVECTIVE TEMP IN LOW 80S AS PROGGED. HAVE MOVED UP TIMING A BIT ON LIKELY POPS. HAD THOUGHT ABOUT TRENDING WITH SCT POPS NW TO NUMEROUS BUT WOULD LIKE TO SEE HOW THINGS EVOLVE BEFORE GETTING LOCKED INTO SPECIFIC WORDING WITH MID LEVEL CAPPING STILL SHOWING UP ON 12Z SOUNDINGS THAT COULD SLOW DOWN DEVELOPMENT UNTIL MCV AND BETTER DYNAMICS APPROACHES LATER TODAY. TEMPS ON TRACK. CHANGED SKY COVER TO REFLECT MORE SUN EARLY WITH INCREASING CLOUDS NW AREAS FIRST TRENDING EVERYWHERE BY LATE AFTN. && .AVIATION... WITH NO CONVECTION ACTIVE AT THE PRESENT TIME...IMMEDIATE CONCERN TURNS TOWARDS PATCHY HZ/BR AT KSBN. WILL THROW IN PREDOMINATE HIGH END MVFR VSBY FOR A FEW HOURS TILL SUN BURNS OFF WHAT IS AROUND. THEN FOCUS TURNS TO MCV MOVING THROUGH MO TOWARDS THE AREA. ITS INTERACTION WITH AN INCREASINGLY UNSTABLE ATMOSPHERE BY THIS AFTERNOON/EVE SHOULD SPARK CONVECTION ACROSS BOTH SITES. WITH MAIN FRONT STILL OFF TO THE WEST...FOCUS FOR CONVECTION IN TERMS OF BOUNDARIES MAY BE DIFFICULT TODAY BUT IF CONVECTION FIRES...WILL DEVELOP FAST AND EXPAND ACROSS THE AREA. FOR NOW WILL KEEP WITH 6Z TAFS OF VC MENTION OF TS/SH FOR NOW AND MONITOR TRENDS. && .PREV DISCUSSION... SHORT TERM... TODAY AND TONIGHT INTERESTING WEATHER SETUP TODAY WITH PLENTY OF CHALLENGES IN STORE FOR TODAYS FORECAST. CURRENT ANALYSIS REVEALS WEAKENING PROGRESSING SPEED MAX PROPAGATING THROUGH LOWER WESTERN MI. A BROKEN LINE OF THUNDERSTORMS EXTENDED SOUTH FROM BALDWIN MI TO SOUTH BEND IN. THIS LINE OF STORMS WAA BEING SUPPORTED BY WEAK THETA E ADVECTION UNDER SEMI-STEEP LAPSE RATES. OTHER ISOLATED CONVECTION WAS TRYING TO DEVELOP IN CENTRAL IL...WHERE LL JET WAS ESTABLISHED...AS INDICATED BY 40 KNOT H85 WIND SPEED ON ILX VWP. FURTHER UPSTREAM...A LARGE AREA OF WEAKENING SHOWERS/THUNDERSTORMS WAS ADVANCING SLOWLY NORTHEAST THROUGH CENTRAL MO. RUC HINTS AT A VORT MAX AT 700MB...AND WITH PREVIOUS INTENSITY OF CONVECTIVE SYSTEM...MCV DEVELOPMENT IS LIKELY IN FULL SWING. THIS WILL LIKELY HAVE A LARGE IMPACT OF PRECIP DEVELOPMENT THIS AFTERNOON. EXPECTING CONVECTION TO DIMINISH ACROSS NORTHWESTERN ZONES THIS MORNING. H5 SPEED MAX ALONG WITH ASSOCIATED LL JET WILL WEAKEN AND PUSH OUT OF THE REGION. HOWEVER...CANNOT RULE OUT ISOLATED THUNDER THREAT INTO MID MORNING GIVEN DEGREE OF INSTABILITY IN PLACE..COUPLED WITH SECONDARY LL SPEED MAX ACROSS CENTRAL IL. FOCUS WILL SHIFT TO DEVELOPING MCV UPSTREAM IN MO. THIS IMPULSE IS PROGGED TO PUSH NORTHEAST INTO FA BY EARLY AFTERNOON WHEN DIURNAL EFFECTS WILL COME INTO PLAY...ALTHOUGH MID CLOUD SHIELD MAY INHIBIT ROBUST HEATING ACROSS WESTERN ZONES. MODELS ALSO SIGNIFICANTLY WEAKEN MCV AS IT LIFTS NORTHEAST INTO FA. HOWEVER...MCV SYSTEMS ARE NOTORIOUSLY POORLY HANDLED BY FORECAST MODELS AND GIVEN THE NUMEROUS LL BOUNDARIES IN PLACE PER RADAR ANALYSIS WITH DEEP MOISTURE CONTINUOUSLY BUILDING INTO THE REGION...HAVE RAISED POPS TO LIKELY ACROSS THE FA FOR ANTICIPATED THUNDERSTORM DEVELOPMENT. SEVERE THREAT IS CERTAINLY POSSIBLE ACROSS FA. WRF INDICATES FAIR AMOUNT OF DRY AIR AT MID LEVELS THIS AFTERNOON. THIS COUPLED WITH STEEP MID LEVEL LAPSE RATES...NEAR INVERTED V SOUNDINGS AND CAPE VALUES AOA 2000 J/KG...ATM WOULD SUPPORT A FEW SEVERE STORMS WITH DAMAGING WIND BEING THE MAIN THREAT. MAIN H5 VORTEX OVER THE NORTHERN PLAINS AND ASSOCIATED SPEED MAX WILL SLOWLY MOVE EAST INTO THE REGION. BEST COMBINATION OF DEEP SHEAR AND LOW LEVEL FORCING SHOULD REMAIN WEST OF FA UNTIL LATE EVENING. THIS SHOULD LIMIT A WIDESPREAD SEVERE RISK OVER FA. THINKING STORMS ACROSS FA WILL MOST LIKELY ORGANIZE INTO A LINE OR LINES AND PUSH NORTHEAST...WITH AMPLE INSTABILITY AND 0-3KM SHEAR IN PLACE. HEAVY RAINFALL WILL BE POSSIBLE WITH ANY THUNDERSTORMS THAT DO DEVELOP GIVEN PRECIP WATER VALUES IN THE 1.5 TO 2 INCH RANGE. PERSISTENT NORTHERN PLAINS UPPER LOW AND ASSOCIATED SFC COLD FRONT WILL PUSH EAST INTO THE GREAT LAKES TONIGHT AND ALLOW SHOWER/THUNDERSTORM CHANCES THROUGH THE NIGHT. OTHERWISE...LOOK FOR ANOTHER WARM DAY ACROSS THE FA WITH THE WARMEST TEMPS IN THE EASTERN ZONES...WHERE TEMPS AROUND 90 ARE POSSIBLE. COOLER H85 TEMPS AND CLOUD COVER SHOULD QUELL EXTREME TEMP RISES ACROSS WESTERN ZONES. LONG TERM... SUNDAY THROUGH FRIDAY COMPLICATED FORECAST WITH REGARD TO DETAILS AND TIMING OF WAVES AND PRECIPITATION THROUGH EARLY PART OF NEXT WEEK. GENERALLY MADE FEW CHANGES TO WEATHER AND POP GRIDS...THOUGH DID TRY AND REFINE A BIT FOR COLLABORATION. UPPER LOW WILL SLOWLY DRIFT EAST INTO THE GREAT LAKES REGION THROUGH EARLY NEXT WEEK. COMPLICATION IN THE FORECAST COMES WITH NORTHWARD MOVEMENT OF TROPICAL SYSTEM THROUGH THE EASTERN CONUS. THIS SLOWS APPROACHING UPPER LOW EVEN MORE. STRONG WAVE AND ASSOCIATED SURFACE FRONT TO BE MOVING THROUGH AT BEGINNING OF THE LONG TERM PERIOD. KEPT LIKELY POPS GOING OVER EASTERN HALF OF THE FORECAST AREA SUNDAY. CONCERNED ABOUT DRY SLOT MOVING IN BUT NOT GOING TO TRY AND TIME THIS UNCERTAINTY AT THIS TIME. UPPER LOW REMAINS ACROSS THE AREA THROUGH MONDAY WITH PCPN CHANCES LINGERING. FIRST PART OF THE WEEK WILL BE COOLER BEHIND DEPARTING LOW AND NORTHERLY FLOW. LATEST MODELS INDICATING THIS COOL STRETCH WILL BE SHORT LIVED AS WARM FRONT DEVELOPS AND MOVES NORTH MID WEEK WITH A RETURN TO VERY WARM AIR POSSIBLE BY THURSDAY. HAVE RAISED HIGHS SEVERAL DEGREES FOR THIS AS ECMWF AND GFS IN AGREEMENT. EXPECT MAX TEMPS BY THU WILL BE CLOSER TO 90 BUT WILL TREND IN THAT DIRECTION AND MONITOR ADDITIONAL MODEL RUNS. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ UPDATE...FISHER AVIATION...CHAMBERLAIN/FISHER SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTHERN INDIANA 750 AM EDT SAT JUN 2 2007 .AVIATION... .AVIATION... WITH NO CONVECTION ACTIVE AT THE PRESENT TIME...IMMEDIATE CONCERN TURNS TOWARDS PATCHY HZ/BR AT KSBN. WILL THROW IN PREDOMINATE HIGH END MVFR VSBY FOR A FEW HOURS TILL SUN BURNS OFF WHAT IS AROUND. THEN FOCUS TURNS TO MCV MOVING THROUGH MO TOWARDS THE AREA. ITS INTERACTION WITH AN INCREASINGLY UNSTABLE ATMOSPHERE BY THIS AFTERNOON/EVE SHOULD SPARK CONVECTION ACROSS BOTH SITES. WITH MAIN FRONT STILL OFF TO THE WEST...FOCUS FOR CONVECTION IN TERMS OF BOUNDARIES MAY BE DIFFICULT TODAY BUT IF CONVECTION FIRES...WILL DEVELOP FAST AND EXPAND ACROSS THE AREA. FOR NOW WILL KEEP WITH 6Z TAFS OF VC MENTION OF TS/SH FOR NOW AND MONITOR TRENDS. && .SHORT TERM... TODAY AND TONIGHT INTERESTING WEATHER SETUP TODAY WITH PLENTY OF CHALLENGES IN STORE FOR TODAYS FORECAST. CURRENT ANALYSIS REVEALS WEAKENING PROGRESSING SPEED MAX PROPAGATING THROUGH LOWER WESTERN MI. A BROKEN LINE OF THUNDERSTORMS EXTENDED SOUTH FROM BALDWIN MI TO SOUTH BEND IN. THIS LINE OF STORMS WAA BEING SUPPORTED BY WEAK THETA E ADVECTION UNDER SEMI-STEEP LAPSE RATES. OTHER ISOLATED CONVECTION WAS TRYING TO DEVELOP IN CENTRAL IL...WHERE LL JET WAS ESTABLISHED...AS INDICATED BY 40 KNOT H85 WIND SPEED ON ILX VWP. FURTHER UPSTREAM...A LARGE AREA OF WEAKENING SHOWERS/THUNDERSTORMS WAS ADVANCING SLOWLY NORTHEAST THROUGH CENTRAL MO. RUC HINTS AT A VORT MAX AT 700MB...AND WITH PREVIOUS INTENSITY OF CONVECTIVE SYSTEM...MCV DEVELOPMENT IS LIKELY IN FULL SWING. THIS WILL LIKELY HAVE A LARGE IMPACT OF PRECIP DEVELOPMENT THIS AFTERNOON. EXPECTING CONVECTION TO DIMINISH ACROSS NORTHWESTERN ZONES THIS MORNING. H5 SPEED MAX ALONG WITH ASSOCIATED LL JET WILL WEAKEN AND PUSH OUT OF THE REGION. HOWEVER...CANNOT RULE OUT ISOLATED THUNDER THREAT INTO MID MORNING GIVEN DEGREE OF INSTABILITY IN PLACE..COUPLED WITH SECONDARY LL SPEED MAX ACROSS CENTRAL IL. FOCUS WILL SHIFT TO DEVELOPING MCV UPSTREAM IN MO. THIS IMPULSE IS PROGGED TO PUSH NORTHEAST INTO FA BY EARLY AFTERNOON WHEN DIURNAL EFFECTS WILL COME INTO PLAY...ALTHOUGH MID CLOUD SHIELD MAY INHIBIT ROBUST HEATING ACROSS WESTERN ZONES. MODELS ALSO SIGNIFICANTLY WEAKEN MCV AS IT LIFTS NORTHEAST INTO FA. HOWEVER...MCV SYSTEMS ARE NOTORIOUSLY POORLY HANDLED BY FORECAST MODELS AND GIVEN THE NUMEROUS LL BOUNDARIES IN PLACE PER RADAR ANALYSIS WITH DEEP MOISTURE CONTINUOUSLY BUILDING INTO THE REGION...HAVE RAISED POPS TO LIKELY ACROSS THE FA FOR ANTICIPATED THUNDERSTORM DEVELOPMENT. SEVERE THREAT IS CERTAINLY POSSIBLE ACROSS FA. WRF INDICATES FAIR AMOUNT OF DRY AIR AT MID LEVELS THIS AFTERNOON. THIS COUPLED WITH STEEP MID LEVEL LAPSE RATES...NEAR INVERTED V SOUNDINGS AND CAPE VALUES AOA 2000 J/KG...ATM WOULD SUPPORT A FEW SEVERE STORMS WITH DAMAGING WIND BEING THE MAIN THREAT. MAIN H5 VORTEX OVER THE NORTHERN PLAINS AND ASSOCIATED SPEED MAX WILL SLOWLY MOVE EAST INTO THE REGION. BEST COMBINATION OF DEEP SHEAR AND LOW LEVEL FORCING SHOULD REMAIN WEST OF FA UNTIL LATE EVENING. THIS SHOULD LIMIT A WIDESPREAD SEVERE RISK OVER FA. THINKING STORMS ACROSS FA WILL MOST LIKELY ORGANIZE INTO A LINE OR LINES AND PUSH NORTHEAST...WITH AMPLE INSTABILITY AND 0-3KM SHEAR IN PLACE. HEAVY RAINFALL WILL BE POSSIBLE WITH ANY THUNDERSTORMS THAT DO DEVELOP GIVEN PRECIP WATER VALUES IN THE 1.5 TO 2 INCH RANGE. PERSISTENT NORTHERN PLAINS UPPER LOW AND ASSOCIATED SFC COLD FRONT WILL PUSH EAST INTO THE GREAT LAKES TONIGHT AND ALLOW SHOWER/THUNDERSTORM CHANCES THROUGH THE NIGHT. OTHERWISE...LOOK FOR ANOTHER WARM DAY ACROSS THE FA WITH THE WARMEST TEMPS IN THE EASTERN ZONES...WHERE TEMPS AROUND 90 ARE POSSIBLE. COOLER H85 TEMPS AND CLOUD COVER SHOULD QUELL EXTREME TEMP RISES ACROSS WESTERN ZONES. && .LONG TERM... SUNDAY THROUGH FRIDAY COMPLICATED FORECAST WITH REGARD TO DETAILS AND TIMING OF WAVES AND PRECIPITATION THROUGH EARLY PART OF NEXT WEEK. GENERALLY MADE FEW CHANGES TO WEATHER AND POP GRIDS...THOUGH DID TRY AND REFINE A BIT FOR COLLABORATION. UPPER LOW WILL SLOWLY DRIFT EAST INTO THE GREAT LAKES REGION THROUGH EARLY NEXT WEEK. COMPLICATION IN THE FORECAST COMES WITH NORTHWARD MOVEMENT OF TROPICAL SYSTEM THROUGH THE EASTERN CONUS. THIS SLOWS APPROACHING UPPER LOW EVEN MORE. STRONG WAVE AND ASSOCIATED SURFACE FRONT TO BE MOVING THROUGH AT BEGINNING OF THE LONG TERM PERIOD. KEPT LIKELY POPS GOING OVER EASTERN HALF OF THE FORECAST AREA SUNDAY. CONCERNED ABOUT DRY SLOT MOVING IN BUT NOT GOING TO TRY AND TIME THIS UNCERTAINTY AT THIS TIME. UPPER LOW REMAINS ACROSS THE AREA THROUGH MONDAY WITH PCPN CHANCES LINGERING. FIRST PART OF THE WEEK WILL BE COOLER BEHIND DEPARTING LOW AND NORTHERLY FLOW. LATEST MODELS INDICATING THIS COOL STRETCH WILL BE SHORT LIVED AS WARM FRONT DEVELOPS AND MOVES NORTH MID WEEK WITH A RETURN TO VERY WARM AIR POSSIBLE BY THURSDAY. HAVE RAISED HIGHS SEVERAL DEGREES FOR THIS AS ECMWF AND GFS IN AGREEMENT. EXPECT MAX TEMPS BY THU WILL BE CLOSER TO 90 BUT WILL TREND IN THAT DIRECTION AND MONITOR ADDITIONAL MODEL RUNS. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ AVIATION...CHAMBERLAIN/FISHER SHORT TERM...CHAMBERLAIN LONG TERM....LASHLEY in AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CARIBOU ME 1055 PM EDT SUN JUN 3 2007 .SYNOPSIS... THE WEAKENING EXTRA-TROPICAL REMAINS OF BARRY WILL APPROACH FROM THE SOUTHWEST TONIGHT AND TRACK THROUGH THE REGION BY MONDAY NIGHT. A COLD FRONT WILL SLOWLY APPROACH FROM THE WEST TUESDAY AND TUESDAY NIGHT AND CROSS THE REGION ON WED. && .NEAR TERM /THROUGH MONDAY/... UPDATED GRIDS/ZFP TO BACK OFF ON RAFL ARRIVING TIL LATER ON TONIGHT PER LATEST RUC & NAM/GFS. LATEST REGIONAL RADAR SHOWING BULK OF THE RAFL JUT MOVING INTO SRN ME (KITTY AND PWM). BROUGHT SKY GRIDS UP TO 100% LATER TONIGHT. TEMPS/DWPTS RUNNING IN LINE. ADDED SOME FOG STARTING FROM 05Z INTO MONDAY MORNING W/ESE FLOW. EXPECT CLOUDS TO CONTINUE TO STREAM NORTHWARD REACHING NORTHERN SECTIONS OVERNIGHT. CLOUDS WILL CONTINUE TO THICKEN AND LOWER TONIGHT AS LOW LEVEL SOUTHEAST FLOW INTENSIFIES. AS USUAL A DIFFERENCE IN THE TIMING BETWEEN THE NAM AND THE GFS WITH THE START OF RAIN WITH THE REMNANTS OF BARRY. USED A COMPROMISE WITH RAIN REACHING DOWNEAST SECTIONS BEFORE DAYBREAK AND THEN REACHING NORTHERN SECTIONS AROUND NOONTIME MONDAY. ALSO USED A BLEND OF THE NAM, GFS, AND HPC FOR QPF AMOUNTS. EXPECT AROUND AN INCH OVER DOWNEAST SECTIONS TAPERING TO HALF AN INCH OVER EXTREME NORTHERN SECTIONS. RAIN TOTAL WILL BE LESS OVER THE NORTH AS UPPER TROUGH WEAKENS AS IT MOVES ACROSS THE STATE. SOUTHEAST FLOW WILL STRENGTHEN MONDAY AFTERNOON AS GRADIENT TIGHTENS IN ADVANCE OF LOW PRESSURE. NAM INDICATES LOW LEVEL JET OF 50 KTS WILL MOVE INTO DOWNEAST ZONES MONDAY AFTERNOON WITH GUSTS TO 35 MPH POSSIBLE. && .SHORT TERM /MONDAY NIGHT THROUGH THURSDAY/... REMNANTS OF BARRY WILL STILL DICTATE THE WEATHER ON MONDAY NIGHT AND TUESDAY. BOTH PERIODS ARE RATHER CLOUDY AND WET. SIMILAR TO PREVIOUS PERIODS...A COMBINATION OF GFS AND NAM WAS USED AS THE PRIMARY GUIDANCE TOOL DURING THIS PERIOD. IN GENERAL WE EXPECT THE GREATEST PRECIPITATION TO OCCUR THROUGH TUESDAY. STORM TOTAL RAINFALL FALL AMOUNTS WILL RANGE IN THE 0.75 TO 1.0 INCH RANGE OVER NORTHERN AND DOWNEAST MAINE. FLOODING IS NOT EXPECTED TO BE A CONCERN GIVEN CURRENT RIVER STAGES. WHAT REMAINS OF THE BARRY`S LOW PRESSURE CENTER THEN MOVES NORTH LEAVING THE AREA IN SOUTHWEST FLOW ALOFT WITH AN UPPER LEVEL TROF TO THE WEST. BECAUSE OF INCREASED INSTABILITY ASSOCIATED WITH THIS TROF...WE DO NOT EXPECT A RAPID CLEARING AFTER TUESDAY. RATHER LINGERING SHOWERS WILL PREVAIL THROUGH WEDNESDAY ESPECIALLY OVER WESTERN ZONES. CONDITIONS IMPROVE GREATLY ON THURSDAY DESPITE A CHANCE OF SHOWERS. && .LONG TERM /THURSDAY NIGHT THROUGH SUNDAY/... CONFIDENCE IN THE LONG TERM MODELS IS LOW WITH RUN TO RUN INCONSISTENCIES AND DISCREPANCIES BETWEEN MODELS. KEPT CLOSE TO HPC GUIDANCE FOR THIS REASON WHICH CLOSELY MATCHED THE 06Z GFS. HIGH PRESSURE LOOKS TO HOLD ON OVER THE AREA FOR FRIDAY INTO FRIDAY NIGHT KEEPING THINGS DRY WITH SKIES MOSTLY CLEAR TO PARTLY CLOUDY INTO FRIDAY NIGHT. BIG QUESTION WILL BE IF FRONTAL SYSTEM ASSOCIATED WITH A LOW OVER NORTHERN QUEBEC WILL MOVE INTO THE AREA. 06Z GFS MOVES IT INTO THE REGION NEXT WEEKEND BRINGING A CHANCE FOR SHOWERS...HOWEVER LATEST 12Z GFS KEEPS FRONT AND SHOWERS TO OUR WEST DUE TO BLOCKING ALOFT. THIS WILL HAVE TO BE MONITORED WITH FUTURE MODEL RUNS...BUT SINCE RELIED ON HPC GUIDANCE FOR THIS PERIOD WENT WITH THE FORMER SOLUTION. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... MVFR CONDITIONS WILL LOWER BACK TO IFR CONDITIONS TONIGHT OVER DOWNEAST SITES AND WILL CONTINUE INTO MONDAY WITH RAIN AND FOG. VFR ACROSS NORTHERN SITES THIS AFTERNOON WILL GRADUALLY LOWER TO MVFR CEILINGS TONIGHT AS REMNANTS OF BARRY APPROACH FROM THE SOUTH. EXPECT IFR CONDITIONS IN RAIN AND FOG FOR NORTHERN SITES BY MONDAY AFTERNOON. && .MARINE... SWELL MOVING UP THE EAST COAST WILL REACH WATERS AFTER MIDNIGHT. SOUTHEAST GRADIENT WILL TIGHTEN ON MONDAY PRODUCING SCA WINDS BY MONDAY AFTERNOON. TO KEEP THINGS SIMPLE SCA STARTS AT MIDNIGHT AND CONTINUES THROUGH MONDAY NIGHT TO COUNT FOR SEAS TONIGHT AND WINDS AND SEAS ON MONDAY. VSBY WILL LOWER TO LESS THAN 1 NM ON MONDAY IN RAIN AND FOG. WINDS ARE EXPECTED TO DECREASE SOME ON TUESDAY. HOWEVER...SEA STATES ARE EXPECTED TO REMAIN ELEVATED DURING THIS PERIOD. SCA MAYBE REQUIRED ON TUESDAY DEPENDING ON THE PERIOD OF THE SWELL. WILL HOLD OFF FOR NOW AND REASSESS LATER. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 AM EDT TUESDAY FOR ANZ050. && $$ NEAR TERM...HEWITT/FOSTER SHORT TERM...LERICOS LONG TERM...WEITLICH AVIATION...FOSTER MARINE...FOSTER/LERICOS me AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MARQUETTE MI 144 AM EDT SUN JUN 3 2007 .SHORT TERM (TONIGHT/SUN)... MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS INDICATED THAT THE SLOW MOVING MID/UPPER LEVEL HAD MOVED INTO SW MN. ONE IN A SERIES OF SHORTWAVE SPOKES AROUND THE LOW SUPPORTED A BAND SHRA FROM W AND CNTRL UPPER MI INTO FAR NE WI AND LAKE MI. NE MOVING TSTMS HAD ALSO DEVELOPED AND MOVED INTO THE BAY OF GREEN BAY NEAR CEDAR RIVER. OTHERWISE...NO OTHER CLOUD TO GROUND LIGHTNING WAS NOTED IN THE CWA. AT THE SFC... AN OCCLUDED FRONT LOOPED FROM SW MN AND NW AND CNTRL WI INTO ERN IA. LITTLE RAIN WAS NOTED BEHIND THE FRONT AND SHRTWV WITH MORE SCT SHRA/TSRA NEAR THE MID LEVEL LOW CENTER. TONIGHT AND SUN...MOST WIDESPREAD PCPN IS EXPECTED THIS EVENING AS THE SHRTWV MOVES THROUGH. THERE MAY BE SOME ADDITIONAL SHRA DEVELOPMENT LATER THIS EVENING AS QVECTOR CONV ASSOCIATED THE MID LEVEL LOW INCREASES AND WEAK LOW LVL CONV PERSISTS VCNTY SFC TROF INTO UPPER MI...PER 18Z RUC. PCPN WITH GREATER QPF WILL BE MORE LIKELY SUNDAY AS THE AREA IS IN A FAVORABLE QUADRANT OF THE MID LEVEL LOW WITH MODERATE TO STRONG 700-300 MB QVECTOR CONV. THE STEEPER MID LEVEL LAPSE RATES AND TSTM CHANCES WILL REMAIN TO THE SOUTH CLOSER TO THE MID LEVEL LOW. WITH ONLY MARGINAL SB OR MUCAPE THIS EVENING OR SUN OF AROUND 500-700 J/KG OR MUCAPE TONIGHT/SUN AND ONLY 30 KT 0-6KM SHEAR INTENSITY OF ANY TSTMS SHOULD REMAIN RELATIVELY WEAK. .LONG TERM (SUN NIGHT THROUGH NEXT SAT) STUBBORN UPPER LOW FINALLY MOVES INTO THE GREAT LAKES SUN NIGHT INTO MON AND EXITS THE REGION ON TUE. FORECAST POSITION OF THE UPPER LOW AXIS CONTINUES TO SLOW...AND THUS...WILL NEED TO LINGER POPS LONGER. DEEP LAYER Q-G FORCING AND ABUNDANT MOISTURE WILL COMBINE AHEAD OF UPR LOW AND DEEPENING SFC LOW OVR LOWER MI TO PLACE MOST OF CWA IN A GOOD AREA FOR PERSISTENT SHOWERS LATE SUN NIGHT INTO MON. THETA-E ADVECTION GRAZES EASTERN ZONES SO KEPT SOME ISOLD THUNDER IN SUNDAY NIGHT...BUT CHANCES SEEM PRETTY SLIM. LATE SUN INTO MON...LEANED ON THE SLOWER AND MORE AMPLIFIED NAM SOLUTION. EAST 2/3 OF CWA WILL BE UNDER THE LINGERING DEFORMATION AREA ON NORTH SIDE OF UPPER LOW. NORTH WINDS IN BLYR WILL ALSO PRODUCE UPSLOPE ENHANCEMENT TO PCPN OVR NCNTRL CWA. NAM/REGIONAL GEM PRINT OUT OVER AN INCH OF QPF SUN NIGHT THROUGH MON IN NCNTRL. TYPE OF SETUP SUPPORTS THIS SOLUTION SO CANNOT COMPLETELY DISCOUNT. SHORTWAVE RIDGING AND DRY ADVECTION IN LOWER LEVELS IS THEN SHOWN BY GFS/UKMET AND EVEN THE NAM BY LATE MON NIGHT. RE-AMPLIFICATION OF UPPER LEVEL TROUGH ON TUE MOSTLY TAKES PLACE OVR EASTERN CANADA AND LOWER GREAT LAKES. LAPSE RATES DO TRY TO STEEPEN OVR NORTHERN PLAINS INTO FAR WESTERN PORTION OF UPPER GREAT LAKES WHERE WARMER TEMPS AT H85 HANG ON. OVERALL THOUGH...INSTABILITY SHOWER CHANCES FOR CWA APPEAR MINIMAL. TRANSITION BEGINS TUE NIGHT AS UPPER PATTERN FLATTENS OUT IN RESPONSE TO STRONG SHORTWAVE PRESSING INTO RIDGE OVR WESTERN CONUS. TUE NIGHT AND WED SHOULD BE DRY. POTENTIAL OF TEMPS IN THE 30S ON TUE NIGHT IN SHELTERED AREAS THAT KEEP MOSTLY CLEAR SKIES. MEANWHILE...PORTION OF SHORTWAVE OVR WESTERN CONUS PRESSES FARTHER INTO THE NORTHERN PLAINS. THIS WAVE IS THE STRONG NORTHERN STREAM SHORTWAVE THAT ECMWF WAS PICKING UP ON LAST COUPLE DAYS. THE SHORTWAVE AND STRENGTH OF IT IS NOW AGREED UPON BY GFS/CANADIAN AND UKMET. QUITE A SFC REFLECTION WITH THE SHORTWAVE WITH HPC PROGS SHOWING A 984MB LOW OVR DAKOTAS ON THU MORNING. A WARM FRONT EXTENDS EAST OF THE LOW INTO THE UPPER GREAT LAKES. MOISTURE INFLOW AHEAD OF LOW IS IMPRESSIVE WITH SOUTH WINDS TO 50KT AT H85. TIMING OF INITIAL WARM FRONT THEN COLD FRONTAL PASSAGE WILL DICTATE WHEN BEST CHANCES OF STORMS WILL BE. H85 TEMPS TO 20C AHEAD OF FRONT COULD POINT TO MAX TEMPS THU AROUND 90. TOO MUCH UNCERTAINTY AT THIS POINT OUT WITH CLOUD COVER AND WARM FRONT POSITION TO GO MUCH ABOVE HPC GUIDANCE. IF WE END UP BEING CAPPED TO CONVECTION FOR MOST OF THE DAY TEMPS THIS WARM OR WARMER ARE A POSSIBILITY. STRENGTH OF DYNAMICS AND EXTENT OF INSTABILITY AND MOISTURE INTO THE SYSTEM SUGGEST POTENTIAL FOR SEVERE STORMS. WILL MENTION POSSIBLE SEVERE IN THE HWO. AFTER THE FRONT PLOWS THROUGH...DRY HIGH PRESSURE SETTLES IN FOR THE FIRST PART OF THE WEEKEND. LOOKS COOLER THAN THU...BUT NOT ALL THAT OFF THE NORMAL FOR EARLY JUNE. && .MARINE... AS THE SFC LOW PRES MOVES THROUGH THE WRN LAKES TONIGHT INTO SUN...NE WINDS OVER W LAKE SUPERIOR WILL DIMINISH THIS EVENING WITH MAINLY LIGHT WINDS OF 10 KT OR LESS THAT WILL BECOME NRLY BY LATE SUN. AREAS OF FOG WILL PERSIST TIL LATER SUNDAY WHEN THE STRONGER NORTH WINDS WILL RESULT IN GREATER DRY ADVECTION AND MIXING. THE GRADIENT BEHIND THE DEPARTING LOW WILL BE TIGHT ENOUGH TO PRODUCE N WINDS GENERALLY IN THE 15 TO 25 KT RANGE WITH AN AREA OF 30 KT WINDS OVER THE E ON MON. COLDER AIR WITH MORE EFFECTIVE MIXING TO THE SFC SHOULD RESULT IN WAVES INTO THE 5 TO 8 FT RANGE. && .AVIATION...06Z TAF ISSUANCE TAFS PROVING TO BE A CHALLENGE EARLY THIS MORNING. KCMX IN PARTICULAR IS JUMPING BETWEEN MVFR AND VLIFR VSBYS. GIVEN THE VARIABILITY THUS FAR...I DECIDED TO KEEP A WIDER VSBY RANGE IN FOR KCMX GOING WITH PREVAILING MVFR AND THEN INCLUDING TEMPO GROUPS FOR VLIFR CONDITIONS INTO LATE MORNING IN CASE DENSE FOG ADVECTS IN OFF LAKE SUPERIOR. DO NOT LOOK FOR MUCH IMPROVEMENT THROUGH THE TAF PERIOD EXCEPT WHEN -SHRA MOVE THROUGH WHICH SHOULD TEND TO IMPROVE VIS SOME. KSAW WILL ALSO BE TRICKY AS LOW CIGS JUST STARTING TO APPEAR THERE. AGAIN I WENT PREVAILING MVFR VSBYS AND INCLUDED TEMPO GROUPS FOR IFR CONDITIONS FOR THE OVERNIGHT PERIOD. LIGHT SOUTHEAST WINDS INITIALLY WILL SHIFT TO THE NORTH BY THIS AFTERNOON. EXPECT ONSHORE/UPSLOPE FLOW OFF LAKE SUPERIOR TO KEEP LOW CLOUDS AND FOG SOCKED IN AT KSAW TODAY INTO TONIGHT. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM/MARINE...JLB LONG TERM...JLA AVIATION...JV mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 140 PM EDT SAT JUN 2 2007 .AVIATION...FOR 18Z TAFS... MVFR CIGS WITH PERIODS OF MVFR VSBY WITH PERIODS OF -SHRA ARE EXPECTED AT KSAW THIS AFTERNOON AND EVENING AS BANDS OF PCPN MOVES THROUGH THE AREA AHEAD OF THE MID LEVEL LOW OVER MOVING INTO SW MN. BY LATER TONIGHT VLIFFR CIGS/VSBYS WILL BE POSSIBLE GIVEN VERY MOIST LOW LEVELS AND PERSISTENT LIGHT SRLY FLOW. AT KCMX THE LIFR CIGS MAY BRIEFLY LIFT LATER THIS AFTERNOON AND EVENING WITH PEAK DIURNAL HEATING. HOWEVER...WITH -SHRA LATE THIS AFTERNOON EVENING COMBINED WITH WITH MOIST WEAK EASTERLY FLOW...CIGS/VSBYS SHOULD AGAIN DROP DOWN TO VLIFR. ONLY SLOW IMPROVEMENT IS EXPECTED BY MID TO LATE MORNING SUN WITH CONTINUED WEAK FLOW AND THE SFC TROF IN THE VCNTY. && .UPDATE...ISSUED 1155 AM EDT SAT JUN 2 2007 RADAR INDICATED THAT SHRA/TSRA MOVING NORTH THROUGH WI HAD WEAKENED. IR IMAGERY ALSO SHOWED THAT CLOUD TOPS HAD WARMED. NEVERTHELESS...EXPECT SCT/NUM SHRA TO MOVE INTO THE WEST HALF OF UPPER MI THIS AFTERNOON AS THE SUPPORTING SHRTWV OVER WI LIFTS TO THE NORTH. CONSIDERABLE CLOUDS HAVE CUT DOWN ON HEATING BUT MAY STILL ALLOW TEMPS TO CLIMB INTO THE MID TO UPPER 70S. TEMPS/DEWPOINT VALUES NEAR 75/60 OVER INTERIOR CNTRL YIELD SBCAPE VALUES IN THE 500-700 J/KG RANGE. SO...ISOLD TSTMS ARE STILL POSSIBLE BY MID AFTERNOON. POPS WERE REDUCED OVER THE EAST WHERE STABILIZING INFLUENCE OF LAKE MI WILL PREVAIL OVER MUCH OF THE AREA. SOME ISOLD -SHRA MAY SURVIVE OVER THE MARINE LAYER ON THE PERIPHERY OF THE SHRTWV. CONV ZONE WITH LK SUPERIOR BREEZE OVER NE CWA MAY ALSO SET OFF SOME ISOLD -SHRA. && .PREV DISCUSSION...ISSUED AT 510 AM EDT SAT JUN 2 2007 MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS SHOWS A CLOSED MID/UPPER LEVEL LOW OVER ERN SD AND A RDG FROM THE OH VALLEY INTO THE CNTRL GREAT LAKES. A SHORTWAVE MOVING THROUGH NRN WI PRODUCED SHRA AND ISOLD TSRA FROM THIS EVENING INTO THE EARLY OVERNIGHT OVER MAINLY THE WESTERN HALF WHERE MUCAPES WERE FROM 200-400 J/KG AND UPR DIV WAS PRESENT AT NOSE OF 3H JET MAX. UNLIKE LAST NIGHT...MID-LVL CLOUDS SPREADING ACROSS THE FCST AREA HAVE GENERALLY PREVENTED RADIATIONAL FOG FROM FORMING OVER INLAND AREAS. HOWEVER...MOIST 50S DEWPOINTS HAVE ALLOWED FOR SOME ADVECTION FOG TO PERSIST OVER THE GREAT LAKES. WEAK ERLY FLOW OVER THE KEWEENAW PENINSULA HAS BROUGHT SOME PATCHY FOG INTO KCMX OVERNIGHT. TODAY...EXPECT ONLY A FEW ISOLD SHRA AROUND THIS MORNING FROM THE INITIAL SHORTWAVE AS IT LIFTS N OF THE AREA. AS THE MID-LVL LOW SLOWLY APPROACHES ANOTHER SHORTWAVE WILL MOVE INTO THE AREA BETWEEN 18-00Z. INCREASING DEEP LAYER QVECTOR CONV...5H DIFFLUENCE AHEAD OF THE APPROACHING MID-LVL LOW/TROF AND LOW LVL CONV NEAR THE ASSOC SFC TROF WILL AID THE DEVELOPMENT OF ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. BEST COVERAGE OF SHRA/TSRA SHOULD BE OVER THE WRN HALF OF UPR MI WHERE MODEL FORECAST MLCAPES ARE EXPECTED TO REACH NEAR 500 J/KG. DECIDED TO BUMP UP SHRA COVERAGE FROM SCT TO NUMEROUS OVER THESE COUNTIES. TONIGHT AND SUNDAY...BEST SHRA COVERAGE SHOULD GRADUALLY SHIFT INTO CENTRAL AND ERN COUNTIES BY LATE TONIGHT INTO SUNDAY AS MID-LVL LOW IS FCST TO BE NEAR KGRB BY 00Z MON. DIURNAL HEATING AND INCREASINGLY INSTABILITY (MLCAPES 200-400 J/KG) WILL INCREASE SHRA/TSRA COVERAGE TO WARRANT LIKELY POPS OVER ALL BUT THE FAR WRN COUNTIES. SUNDAY NIGHT AND MONDAY...MID-LVL TROUGH AXIS WILL CONTINUE TO MOVE SLOWLY E REACHING NORTHERN LOWER MICHIGAN AND EASTERN UPPER MICHIGAN BY LATE MON. LOOK FOR DEFORMATION PCPN TO WRAP BACK INTO MAINLY THE ERN HALF OF THE FCST AREA. CYCLONIC FLOW IN LOWER LEVELS ON THE BACKSIDE OF THE TROF WILL ALSO AID CONVERGENCE AND LIKELY ENHANCE PCPN. WILL KEEP CHC POPS IN FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING/SUBSIDENCE WORKING IN FM THE NORTHWEST SHOULD END SHRA OVR WESTERN COUNTIES EARLY MON. ANOTHER SHORTWAVE MOVING DOWN IN A NW FLOW WILL WARRANT MAINTAINING LOW CHC POPS FOR THE ENTIRE CWA MON NIGHT INTO TUE. && .MARINE (FOR 4 AM GLF ISSUANCE)... LOW PRES OF 29.7 INCHES ACROSS SOUTHERN AND EASTERN MINNESOTA WILL CONTINUE TO SLOWLY SLIDE EASTWARD...REACHING NORTHEASTERN WISCONSIN AT 29.6 INCHES EARLY SUN MORNING...BEFORE REACHING SOUTHERN QUEBEC AT 29.2 INCHES ON TUE MORNING. AS THIS LOW EXITS...HIGH PRES OF 29.8 INCHES OVER CENTRAL CANADA ON TUE WILL EXPAND OVER THE UPPER GREAT LAKES THROUGH WED. WINDS ACROSS THE NW THIRD OF THE LAKE HAVE BEEN A LITTLE TRICKY THIS MORNING...WITH THE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS STRETCHED ACROSS THE WEST PARALLEL TO THE SHORELINE. FOR THIS ISSUANCE MAKE ONLY MINOR CHANGES...BUT DID INCREASE WIND/GUSTS ON MONDAY TO UP TO 30KT MAINLY ACROSS THE EAST HALF. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...VOSS AVIATION/MARINE...KF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1155 AM EDT SAT JUN 2 2007 .UPDATE... RADAR INDICATED THAT SHRA/TSRA MOVING NORTH THROUGH WI HAD WEAKENED. IR IMAGERY ALSO SHOWED THAT CLOUD TOPS HAD WARMED. NEVERTHELESS...EXPECT SCT/NUM SHRA TO MOVE INTO THE WEST HALF OF UPPER MI THIS AFTERNOON AS THE SUPPORTING SHRTWV OVER WI LIFTS TO THE NORTH. CONSIDERABLE CLOUDS HAVE CUT DOWN ON HEATING BUT MAY STILL ALLOW TEMPS TO CLIMB INTO THE MID TO UPPER 70S. TEMPS/DEWPOINT VALUES NEAR 75/60 OVER INTERIOR CNTRL YIELD SBCAPE VALUES IN THE 500-700 J/KG RANGE. SO...ISOLD TSTMS ARE STILL POSSIBLE BY MID AFTERNOON. POPS WERE REDUCED OVER THE EAST WHERE STABILIZING INFLUENCE OF LAKE MI WILL PREVAIL OVER MUCH OF THE AREA. SOME ISOLD -SHRA MAY SURVIVE OVER THE MARINE LAYER ON THE PERIPHERY OF THE SHRTWV. CONV ZONE WITH LK SUPERIOR BREEZE OVER NE CWA MAY ALSO SET OFF SOME ISOLD -SHRA. && .AVIATION...FOR 12Z TAFS...ISSUED 715 AM EDT SAT JUN 2 2007 DESPITE THE 4-6 HOUR BREAK FROM FOG AT KCMX...CEIGS AND VIS HAVE ONCE AGAIN COME DOWN TO LIFR AROUND SUNRISE. EVEN THE HIGH CLOUDS THAT WERE PREDOMINATE OVERNIGHT AT KSAW HAVE NOW BEEN REPLACED BY LOWER LEVEL CLOUDS. LOOKING AT THE LATEST SATELLITE IMAGERY...THE LOWER CLOUDS STRETCH DOWN THROUGH NORTHCENTRAL WISCONSIN...WITH SOME PATCHINESS. AS A RESULT...ONLY MINOR IMPROVEMENT IS FIGURED OVER THE NEXT SEVERAL HOURS...WITH THE POTENTIAL FOR IFR-LIFR CEIGS AND VIS WITH ANY SHOWERS OR THUNDERSTORMS THAT ROLL THROUGH MAINLY FROM MID AFTERNOON ON THROUGH AROUND THE 06-09Z TIME PERIOD. && .PREV DISCUSSION...ISSUED AT 510 AM EDT SAT JUN 2 2007 MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS SHOWS A CLOSED MID/UPPER LEVEL LOW OVER ERN SD AND A RDG FROM THE OH VALLEY INTO THE CNTRL GREAT LAKES. A SHORTWAVE MOVING THROUGH NRN WI PRODUCED SHRA AND ISOLD TSRA FROM THIS EVENING INTO THE EARLY OVERNIGHT OVER MAINLY THE WESTERN HALF WHERE MUCAPES WERE FROM 200-400 J/KG AND UPR DIV WAS PRESENT AT NOSE OF 3H JET MAX. UNLIKE LAST NIGHT...MID-LVL CLOUDS SPREADING ACROSS THE FCST AREA HAVE GENERALLY PREVENTED RADIATIONAL FOG FROM FORMING OVER INLAND AREAS. HOWEVER...MOIST 50S DEWPOINTS HAVE ALLOWED FOR SOME ADVECTION FOG TO PERSIST OVER THE GREAT LAKES. WEAK ERLY FLOW OVER THE KEWEENAW PENINSULA HAS BROUGHT SOME PATCHY FOG INTO KCMX OVERNIGHT. TODAY...EXPECT ONLY A FEW ISOLD SHRA AROUND THIS MORNING FROM THE INITIAL SHORTWAVE AS IT LIFTS N OF THE AREA. AS THE MID-LVL LOW SLOWLY APPROACHES ANOTHER SHORTWAVE WILL MOVE INTO THE AREA BETWEEN 18-00Z. INCREASING DEEP LAYER QVECTOR CONV...5H DIFFLUENCE AHEAD OF THE APPROACHING MID-LVL LOW/TROF AND LOW LVL CONV NEAR THE ASSOC SFC TROF WILL AID THE DEVELOPMENT OF ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. BEST COVERAGE OF SHRA/TSRA SHOULD BE OVER THE WRN HALF OF UPR MI WHERE MODEL FORECAST MLCAPES ARE EXPECTED TO REACH NEAR 500 J/KG. DECIDED TO BUMP UP SHRA COVERAGE FROM SCT TO NUMEROUS OVER THESE COUNTIES. TONIGHT AND SUNDAY...BEST SHRA COVERAGE SHOULD GRADUALLY SHIFT INTO CENTRAL AND ERN COUNTIES BY LATE TONIGHT INTO SUNDAY AS MID-LVL LOW IS FCST TO BE NEAR KGRB BY 00Z MON. DIURNAL HEATING AND INCREASINGLY INSTABILITY (MLCAPES 200-400 J/KG) WILL INCREASE SHRA/TSRA COVERAGE TO WARRANT LIKELY POPS OVER ALL BUT THE FAR WRN COUNTIES. SUNDAY NIGHT AND MONDAY...MID-LVL TROUGH AXIS WILL CONTINUE TO MOVE SLOWLY E REACHING NORTHERN LOWER MICHIGAN AND EASTERN UPPER MICHIGAN BY LATE MON. LOOK FOR DEFORMATION PCPN TO WRAP BACK INTO MAINLY THE ERN HALF OF THE FCST AREA. CYCLONIC FLOW IN LOWER LEVELS ON THE BACKSIDE OF THE TROF WILL ALSO AID CONVERGENCE AND LIKELY ENHANCE PCPN. WILL KEEP CHC POPS IN FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING/SUBSIDENCE WORKING IN FM THE NORTHWEST SHOULD END SHRA OVR WESTERN COUNTIES EARLY MON. ANOTHER SHORTWAVE MOVING DOWN IN A NW FLOW WILL WARRANT MAINTAINING LOW CHC POPS FOR THE ENTIRE CWA MON NIGHT INTO TUE. && .MARINE (FOR 4 AM GLF ISSUANCE)... LOW PRES OF 29.7 INCHES ACROSS SOUTHERN AND EASTERN MINNESOTA WILL CONTINUE TO SLOWLY SLIDE EASTWARD...REACHING NORTHEASTERN WISCONSIN AT 29.6 INCHES EARLY SUN MORNING...BEFORE REACHING SOUTHERN QUEBEC AT 29.2 INCHES ON TUE MORNING. AS THIS LOW EXITS...HIGH PRES OF 29.8 INCHES OVER CENTRAL CANADA ON TUE WILL EXPAND OVER THE UPPER GREAT LAKES THROUGH WED. WINDS ACROSS THE NW THIRD OF THE LAKE HAVE BEEN A LITTLE TRICKY THIS MORNING...WITH THE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS STRETCHED ACROSS THE WEST PARALLEL TO THE SHORELINE. FOR THIS ISSUANCE MAKE ONLY MINOR CHANGES...BUT DID INCREASE WIND/GUSTS ON MONDAY TO UP TO 30KT MAINLY ACROSS THE EAST HALF. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...VOSS AVIATION/MARINE...KF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1048 AM EDT SAT JUN 2 2007 .UPDATED... I LOWERED THE POP THIS AFTERNOON OVER ALL OF THE CWA TO CHC SINCE I DO NOT SEE ANY REAL MECHANISM FOR THUNDERSTORM GENERATION OTHER THEN THE LAKE BREEZE BOUNDARY INTRACTION. TRUE...THERE ARE DECENT CAPES AND THE SURFACED BASED LI VALUES WILL BE NEGATIVE OVER JUST ABOUT ALL OF THE CWA. EVEN SO...THE DNVA BEHIND THE EARLY MORNING CONVECTION SHOULD SUPPRESS CONVECTION INTO MID AFTERNOON. MEANWHILE SHORTWAVE ENERGY NEAR CHI AT 15Z MAY AID LAKE BREEZE CONVECTION NEAR US-131 BY MID AFTERNOON. DUE TO THE LAKE BREEZE INTERACTION WITH THE SHORTWAVE THIS AFTERNOON I DO HAVE LIKELY POP NEAR US-131 BY MID AFTERNOON. THAT CONVECTION WILL LIKELY MOVE INLAND THIS EVENING BEFORE WEAKENING WITH THE LOSS OF SOLAR ENERGY. THUS I KEEP THE NUMEROUS WORDING EARLY EVENING HOURS FOR THUNDERSTORMS. AS FOR SEVERE THUNDERSTORMS...CAPES ARE IMPRESSIVE BUT THE WIND FIELD THROUGH MID LEVELS IN NOT CONDUCIVE TO SEVERE WEATHER. FREEZING LEVELS ON TAMDAR AT 12-14Z ARE SLOPE UP FROM 12000 FT NEAR JXN TO 1300 FT NEAR THE LAKE MICHIGAN SHORE. THE HIGH FREEZING LEVELS AT FIRST GLANCE WOULD NOT SUPPORT HAIL. HOWEVER...MODEL FORECAST SOUNDING SUGGEST PULSE LARGE HAIL IS NOT OUT OF THE QUESTION SINCE BASED ON THE RUC MODEL SOUNDINGS THERE IS A FAIR AMOUNT OF CAPE ABOVE THE -10C LEVEL. THE NAM IS MORE CONSERVATIVE. THE BIG QUESTION IS WILL THE LOW LEVEL DEW POINTS LOWER THIS AFTERNOON AS DEEPER MIXING OCCURS. IF SO ALL BETS OF OFF FOR ANY SEVERE WEATHER OVER THE GRR CWA TODAY OR TONIGHT. THE REST OF THE ZONE FORECAST SEEMS TO BE ON TRACK... SO THAT REMAINS AS IS. .PREVIOUS DISCUSSION... WV IMAGERY THIS MORNING SHOWS THE UPPER LOW CONTINUING TO SPIN OVER THE PLAINS STATES EARLY THIS MORNING. THE LOW IS CURRENTLY CENTERED OVER THE ERN BORDER OF SOUTH DAKOTA AND NEBRASKA. AHEAD OF THE UPPER LOW IS A NICE BELT OF DEEP SW FLOW WITH EMBEDDED SHORT WAVES RIDING TO THE NE. OUR MAIN CONCERN IN THE SHORT TERM PORTION OF THE FORECAST IS PCPN CHCS AND SEVERE POTENTIAL FROM TODAY RIGHT ON THROUGH MON AS THE UPPER LOW MOVES TOWARD THE AREA THROUGH SUN AND IS THEN RIGHT OVERHEAD LATE SUN INTO MON. REMNANTS OF THE LINE OF CONVECTION THAT AFFECTED AREAS TO OUR WEST OVER IA/IL/WI DURING THE DAY ON FRI...ARE CURRENTLY MOVING THROUGH THE CWFA THIS MORNING. THE CONVECTION HAS DIMINISHED SIGNIFICANTLY... HOWEVER DUE TO MESOSCALE EFFECTS AND AN INSTABILITY AXIS ALOFT... SOME OF THE CONVECTION HAS MAINTAINED ITSELF AS IT MOVES NE. THIS BATCH OF CONVECTION WILL MOVE EAST OF THE CWFA BY 12Z...LEAVING THE AREA IN A RELATIVE VOID OF MOST PCPN TEMPORARILY. CLOUDS SHOULD BE SOMEWHAT LIMITED THIS MORNING WITH DEBRIS FROM UPSTREAM CONVECTION RESPONSIBLE MOST CLOUD COVER INITIALLY. BREAKS IN THE CLOUDS MAY ALLOW FOR SOME FOG TO DEVELOP WITH THE HIGHER DEW POINTS IN PLACE...ESPECIALLY AT LOCATIONS THAT HAVE SEEN SOME RAIN THIS MORNING. AFTER ANY FOG DISSIPATES...SOME SUN WILL HELP WARM TEMPS BACK INTO THE 80S ACROSS MOST OF THE CWFA. SUN WILL BE SOMEWHAT LIMITED AFTER THE MORNING AS ADDITIONAL DEBRIS CLOUD COVER FROM CONVECTION SW OF THE AREA WILL STREAM INTO THE AREA. ADDITIONAL WAVES THAT CAN BE SEEN FROM LOWER MICHIGAN BACK DOWN INTO THE MO AREA WILL TEND TO MOVE TOWARD THE AREA THIS MORNING. HOW MUCH WE DESTABILIZE OBVIOUSLY HAS TO DO WITH HOW MUCH SUN WE CAN GET...AND THIS DEPENDS ON THE TIMING OVER UPSTREAM SHORT WAVES. ASSUMING WE CAN GET A FAIR AMOUNT OF SUN THIS MORNING...MODIFIED FCST SOUNDINGS FOR THIS AFTERNOON WITH TEMPS IN THE MID 80S AND DEW POINTS IN THE LOW TO MID 60S WOULD SUPPORT SB CAPES AROUND 2000 J/KG AND SB LI/S AROUND -5. WITH SHORT WAVES EXPECTED TO BEGIN MOVING ACROSS THE AREA LATER TODAY AS THE UPPER LOW APPROACHES THE AREA...THIS SUPPORTS A BETTER THREAT OF CONVECTION THAN WHAT HAS BEEN PRESENT THE PAST FEW DAYS. DEEP LAYER SHEAR ON A SYNOPTIC SCALE IS NOT VERY IMPRESSIVE FOR MOST OF THE DAY AS MID LEVEL WINDS ARE ONLY 25 TO 30 KTS GIVING SHEAR VALUES OF 20 KTS OR SO. DEEP LAYER SHEAR DOES INCREASE LATE FROM THE NW AS THE MID LEVEL JET MOVES IN. ALSO IF ANY CONVECTIVELY INDUCED VORT MOVES IN...THERE WOULD BE SOME GOOD LOCALIZED SHEAR PRESENT. POTENTIAL INSTABILITY COULD MAKE UP FOR THIS AND PRODUCE A WIND AND HAIL THREAT...ESPECIALLY LATER AS THE SHEAR INCREASES. WE HAVE INCREASED THE POPS IN THE AFTERNOON AND EVENING HOURS TO THE LIKELY/NUMEROUS CATEGORY. WITH THE LOSS OF DIURNAL INSTABILITY...THE THREAT OF WIDESPREAD STORMS AND SEVERE WEATHER WILL DIMINISH BY THE OVERNIGHT HOURS. THE THREAT OF SHOWERS AND STORMS WILL REMAIN THOUGH WITH THE AREA REMAINING PRONE TO SHORT WAVES RIDING NE ALONG THE MID LEVEL FLOW. WE HAVE TRENDED POPS LOWER FOR THE SECOND HALF OF THE NIGHT TONIGHT. THE UPPER LOW WILL THEN FINALLY MOVE NEARBY DURING THE COURSE OF THE DAY ON SUN ALONG WITH THE ASSOCIATED SFC FRONT. A FEW PEEKS OF SUN WILL BE POSSIBLE SUN MORNING...BUT WITH THE COLD POOL ALOFT MOVING OVERHEAD AND PLENTY OF LOW LEVEL MOISTURE...BREAKS IN THE CLOUDS WILL FILL IN AND SHOWERS AND STORMS WILL BEGIN DEVELOPING. INSTABILITY WILL NOT BE AS FAVORABLE AS SFC TEMPS WILL ONLY RISE INTO THE 70S. HOWEVER DEW POINTS STILL IN THE 50S AND LOWER 60S WILL ACT WITH COLD POOL ALOFT TO PROVIDE AROUND 1000 J/KG OF SB CAPE AND LI/S AROUND -3. DEEP LAYER SHEAR WILL BE MUCH BETTER WITH THE MID LEVEL JET MOVING OVERHEAD DURING THE DAY. SEVERE HAIL WILL BE POSSIBLE DUE TO FREEZING LEVELS OF ONLY AROUND 9K TO 10K FEET...AND SOME DOWNBURSTS WILL BE POSSIBLE WITH THE BETTER ORGANIZED STORMS. THE POTENTIAL OF PCPN WILL THEN DIMINISH SOMEWHAT ON MON AS THE UPPER LOW FINALLY OPENS UP INTO A WAVE AND THE BETTER MOISTURE MOVES EAST OF THE AREA. A FEW INSTABILITY SHOWERS WILL BE POSSIBLE MON AFTERNOON. THUNDER WILL REMAIN POSSIBLE AS THE COLD POOL ALOFT REMAINS OVERHEAD AND LI/S REMAIN SLIGHTLY NEGATIVE. TEMPS ON MON WILL LIKELY ONLY WARM INTO THE MID 60S TO LOWER 70S WITH THE THERMAL TROUGH MOVING IN. .LONG TERM... MON THROUGH FRI...MID AND UPPER LEVEL CYCLONIC FLOW CONTINUES THROUGH TUE WITH BUILDING HEIGHTS LATE ON TUE INTO THU AS WRN RIDGE BUILD EWD. ON TUE LATEST GFS/ECMWF SHOWING WEAK S/W ENERGY MOVING THROUGH TROF...SO THINKING IS FOR SCT SHOWER THREAT ESPECIALLY WITH AFTN DIURNAL HEAT MAX. TEMPS WILL START OUT BELOW NORMAL AND TREND UPWARDS TOWARDS THU. BY THU EARLY AM WARM FRONT PUSHES INTO AREA WITH S/W ENERGY DIGGING ESE AS IT TOPS RIDGE AXIS ALOFT. THIS WOULD BE A GOOD SCENARIO FOR EARLY MORNING MCS EVENT. BUMPED POPS A FEW PERCENT TO START A TREND TOWARDS POTENTIAL EVENT. $$ .GRR WATCHES/WARNINGS/ADVISORIES...NONE && $$ NJJ COBB WDM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 515 AM EDT SAT JUN 2 2007 .AVIATION...FOR 12Z TAFS... DESPITE THE 4-6 HOUR BREAK FROM FOG AT KCMX...CEIGS AND VIS HAVE ONCE AGAIN COME DOWN TO LIFR AROUND SUNRISE. EVEN THE HIGH CLOUDS THAT WERE PREDOMINATE OVERNIGHT AT KSAW HAVE NOW BEEN REPLACED BY LOWER LEVEL CLOUDS. LOOKING AT THE LATEST SATELLITE IMAGERY...THE LOWER CLOUDS STRETCH DOWN THROUGH NORTHCENTRAL WISCONSIN...WITH SOME PATCHINESS. AS A RESULT...ONLY MINOR IMPROVEMENT IS FIGURED OVER THE NEXT SEVERAL HOURS...WITH THE POTENTIAL FOR IFR-LIFR CEIGS AND VIS WITH ANY SHOWERS OR THUNDERSTORMS THAT ROLL THROUGH MAINLY FROM MID AFTERNOON ON THROUGH AROUND THE 06-09Z TIME PERIOD. && .DISCUSSION...ISSUED AT 510 AM EDT SAT JUN 2 2007 MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS SHOWS A CLOSED MID/UPPER LEVEL LOW OVER ERN SD AND A RDG FROM THE OH VALLEY INTO THE CNTRL GREAT LAKES. A SHORTWAVE MOVING THROUGH NRN WI PRODUCED SHRA AND ISOLD TSRA FROM THIS EVENING INTO THE EARLY OVERNIGHT OVER MAINLY THE WESTERN HALF WHERE MUCAPES WERE FROM 200-400 J/KG AND UPR DIV WAS PRESENT AT NOSE OF 3H JET MAX. UNLIKE LAST NIGHT...MID-LVL CLOUDS SPREADING ACROSS THE FCST AREA HAVE GENERALLY PREVENTED RADIATIONAL FOG FROM FORMING OVER INLAND AREAS. HOWEVER...MOIST 50S DEWPOINTS HAVE ALLOWED FOR SOME ADVECTION FOG TO PERSIST OVER THE GREAT LAKES. WEAK ERLY FLOW OVER THE KEWEENAW PENINSULA HAS BROUGHT SOME PATCHY FOG INTO KCMX OVERNIGHT. TODAY...EXPECT ONLY A FEW ISOLD SHRA AROUND THIS MORNING FROM THE INITIAL SHORTWAVE AS IT LIFTS N OF THE AREA. AS THE MID-LVL LOW SLOWLY APPROACHES ANOTHER SHORTWAVE WILL MOVE INTO THE AREA BETWEEN 18-00Z. INCREASING DEEP LAYER QVECTOR CONV...5H DIFFLUENCE AHEAD OF THE APPROACHING MID-LVL LOW/TROF AND LOW LVL CONV NEAR THE ASSOC SFC TROF WILL AID THE DEVELOPMENT OF ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. BEST COVERAGE OF SHRA/TSRA SHOULD BE OVER THE WRN HALF OF UPR MI WHERE MODEL FORECAST MLCAPES ARE EXPECTED TO REACH NEAR 500 J/KG. DECIDED TO BUMP UP SHRA COVERAGE FROM SCT TO NUMEROUS OVER THESE COUNTIES. TONIGHT AND SUNDAY...BEST SHRA COVERAGE SHOULD GRADUALLY SHIFT INTO CENTRAL AND ERN COUNTIES BY LATE TONIGHT INTO SUNDAY AS MID-LVL LOW IS FCST TO BE NEAR KGRB BY 00Z MON. DIURNAL HEATING AND INCREASINGLY INSTABILITY (MLCAPES 200-400 J/KG) WILL INCREASE SHRA/TSRA COVERAGE TO WARRANT LIKELY POPS OVER ALL BUT THE FAR WRN COUNTIES. SUNDAY NIGHT AND MONDAY...MID-LVL TROUGH AXIS WILL CONTINUE TO MOVE SLOWLY E REACHING NORTHERN LOWER MICHIGAN AND EASTERN UPPER MICHIGAN BY LATE MON. LOOK FOR DEFORMATION PCPN TO WRAP BACK INTO MAINLY THE ERN HALF OF THE FCST AREA. CYCLONIC FLOW IN LOWER LEVELS ON THE BACKSIDE OF THE TROF WILL ALSO AID CONVERGENCE AND LIKELY ENHANCE PCPN. WILL KEEP CHC POPS IN FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING/SUBSIDENCE WORKING IN FM THE NORTHWEST SHOULD END SHRA OVR WESTERN COUNTIES EARLY MON. ANOTHER SHORTWAVE MOVING DOWN IN A NW FLOW WILL WARRANT MAINTAINING LOW CHC POPS FOR THE ENTIRE CWA MON NIGHT INTO TUE. && .MARINE (FOR 4 AM GLF ISSUANCE)... LOW PRES OF 29.7 INCHES ACROSS SOUTHERN AND EASTERN MINNESOTA WILL CONTINUE TO SLOWLY SLIDE EASTWARD...REACHING NORTHEASTERN WISCONSIN AT 29.6 INCHES EARLY SUN MORNING...BEFORE REACHING SOUTHERN QUEBEC AT 29.2 INCHES ON TUE MORNING. AS THIS LOW EXITS...HIGH PRES OF 29.8 INCHES OVER CENTRAL CANADA ON TUE WILL EXPAND OVER THE UPPER GREAT LAKES THROUGH WED. WINDS ACROSS THE NW THIRD OF THE LAKE HAVE BEEN A LITTLE TRICKY THIS MORNING...WITH THE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS STRETCHED ACROSS THE WEST PARALLEL TO THE SHORELINE. FOR THIS ISSUANCE MAKE ONLY MINOR CHANGES...BUT DID INCREASE WIND/GUSTS ON MONDAY TO UP TO 30KT MAINLY ACROSS THE EAST HALF. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...VOSS AVIATION/MARINE...KF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 510 AM EDT SAT JUN 2 2007 .DISCUSSION... MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS SHOWS A CLOSED MID/UPPER LEVEL LOW OVER ERN SD AND A RDG FROM THE OH VALLEY INTO THE CNTRL GREAT LAKES. A SHORTWAVE MOVING THROUGH NRN WI PRODUCED SHRA AND ISOLD TSRA FROM THIS EVENING INTO THE EARLY OVERNIGHT OVER MAINLY THE WESTERN HALF WHERE MUCAPES WERE FROM 200-400 J/KG AND UPR DIV WAS PRESENT AT NOSE OF 3H JET MAX. UNLIKE LAST NIGHT...MID-LVL CLOUDS SPREADING ACROSS THE FCST AREA HAVE GENERALLY PREVENTED RADIATIONAL FOG FROM FORMING OVER INLAND AREAS. HOWEVER...MOIST 50S DEWPOINTS HAVE ALLOWED FOR SOME ADVECTION FOG TO PERSIST OVER THE GREAT LAKES. WEAK ERLY FLOW OVER THE KEWEENAW PENINSULA HAS BROUGHT SOME PATCHY FOG INTO KCMX OVERNIGHT. TODAY...EXPECT ONLY A FEW ISOLD SHRA AROUND THIS MORNING FROM THE INITIAL SHORTWAVE AS IT LIFTS N OF THE AREA. AS THE MID-LVL LOW SLOWLY APPROACHES ANOTHER SHORTWAVE WILL MOVE INTO THE AREA BETWEEN 18-00Z. INCREASING DEEP LAYER QVECTOR CONV...5H DIFFLUENCE AHEAD OF THE APPROACHING MID-LVL LOW/TROF AND LOW LVL CONV NEAR THE ASSOC SFC TROF WILL AID THE DEVELOPMENT OF ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. BEST COVERAGE OF SHRA/TSRA SHOULD BE OVER THE WRN HALF OF UPR MI WHERE MODEL FORECAST MLCAPES ARE EXPECTED TO REACH NEAR 500 J/KG. DECIDED TO BUMP UP SHRA COVERAGE FROM SCT TO NUMEROUS OVER THESE COUNTIES. TONIGHT AND SUNDAY...BEST SHRA COVERAGE SHOULD GRADUALLY SHIFT INTO CENTRAL AND ERN COUNTIES BY LATE TONIGHT INTO SUNDAY AS MID-LVL LOW IS FCST TO BE NEAR KGRB BY 00Z MON. DIURNAL HEATING AND INCREASINGLY INSTABILITY (MLCAPES 200-400 J/KG) WILL INCREASE SHRA/TSRA COVERAGE TO WARRANT LIKELY POPS OVER ALL BUT THE FAR WRN COUNTIES. SUNDAY NIGHT AND MONDAY...MID-LVL TROUGH AXIS WILL CONTINUE TO MOVE SLOWLY E REACHING NORTHERN LOWER MICHIGAN AND EASTERN UPPER MICHIGAN BY LATE MON. LOOK FOR DEFORMATION PCPN TO WRAP BACK INTO MAINLY THE ERN HALF OF THE FCST AREA. CYCLONIC FLOW IN LOWER LEVELS ON THE BACKSIDE OF THE TROF WILL ALSO AID CONVERGENCE AND LIKELY ENHANCE PCPN. WILL KEEP CHC POPS IN FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING/SUBSIDENCE WORKING IN FM THE NORTHWEST SHOULD END SHRA OVR WESTERN COUNTIES EARLY MON. ANOTHER SHORTWAVE MOVING DOWN IN A NW FLOW WILL WARRANT MAINTAINING LOW CHC POPS FOR THE ENTIRE CWA MON NIGHT INTO TUE. && .MARINE (FOR 4 AM GLF ISSUANCE)... LOW PRES OF 29.7 INCHES ACROSS SOUTHERN AND EASTERN MINNESOTA WILL CONTINUE TO SLOWLY SLIDE EASTWARD...REACHING NORTHEASTERN WISCONSIN AT 29.6 INCHES EARLY SUN MORNING...BEFORE REACHING SOUTHERN QUEBEC AT 29.2 INCHES ON TUE MORNING. AS THIS LOW EXITS...HIGH PRES OF 29.8 INCHES OVER CENTRAL CANADA ON TUE WILL EXPAND OVER THE UPPER GREAT LAKES THROUGH WED. WINDS ACROSS THE NW THIRD OF THE LAKE HAVE BEEN A LITTLE TRICKY THIS MORNING...WITH THE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS STRETCHED ACROSS THE WEST PARALLEL TO THE SHORELINE. FOR THIS ISSUANCE MAKE ONLY MINOR CHANGES...BUT DID INCREASE WIND/GUSTS ON MONDAY TO UP TO 30KT MAINLY ACROSS THE EAST HALF. && .AVIATION (FOR 06Z TAFS)... TOUGH FORECAST COMING UP WITH LOW CLOUDS AND FOG TO KCMX AND HIGH CLOUDS AT KSAW. FEELING IS MORE OF THE SAME WILL CONTINUE WITH LOW CLOUDS AND FOG BEING ADVECTED INTO KCMX OVERNIGHT WITH EAST WINDS. LIFR CEIGS AND VIS...AND DO NOT SEE ANY IMPROVEMENTS THERE AS WINDS WILL CONTINUE TO ADVECT OFF LAKE SUPERIOR. LIFR CEIGS AT KSAW EXPECTED AS RAIN MOVES IN...POSSIBLY GOING TO MVFR WITH SOUTH WINDS...ALONG WITH THE SMALL CHANCE OF INCREASED FOG IF ITS ABLE TO ADVECT IN FROM LAKE MICHIGAN. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...VOSS AVIATION/MARINE...KF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 319 AM EDT SAT JUN 2 2007 .MARINE (FOR 4 AM GLF ISSUANCE)... LOW PRES OF 29.7 INCHES ACROSS SOUTHERN AND EASTERN MINNESOTA WILL CONTINUE TO SLOWLY SLIDE EASTWARD...REACHING NORTHEASTERN WISCONSIN AT 29.6 INCHES EARLY SUN MORNING...BEFORE REACHING SOUTHERN QUEBEC AT 29.2 INCHES ON TUE MORNING. AS THIS LOW EXITS...HIGH PRES OF 29.8 INCHES OVER CENTRAL CANADA ON TUE WILL EXPAND OVER THE UPPER GREAT LAKES THROUGH WED. WINDS ACROSS THE NW THIRD OF THE LAKE HAVE BEEN A LITTLE TRICKY THIS MORNING...WITH THE BAND OF SHOWERS AND ISOLATED THUNDERSTORMS STRETCHED ACROSS THE WEST PARALLEL TO THE SHORELINE. FOR THIS ISSUANCE MAKE ONLY MINOR CHANGES...BUT DID INCREASE WIND/GUSTS ON MONDAY TO UP TO 30KT MAINLY ACROSS THE EAST HALF. && .AVIATION (FOR 06Z TAFS)... TOUGH FORECAST COMING UP WITH LOW CLOUDS AND FOG TO KCMX AND HIGH CLOUDS AT KSAW. FEELING IS MORE OF THE SAME WILL CONTINUE WITH LOW CLOUDS AND FOG BEING ADVECTED INTO KCMX OVERNIGHT WITH EAST WINDS. LIFR CEIGS AND VIS...AND DO NOT SEE ANY IMPROVEMENTS THERE AS WINDS WILL CONTINUE TO ADVECT OFF LAKE SUPERIOR. LIFR CEIGS AT KSAW EXPECTED AS RAIN MOVES IN...POSSIBLY GOING TO MVFR WITH SOUTH WINDS...ALONG WITH THE SMALL CHANCE OF INCREASED FOG IF ITS ABLE TO ADVECT IN FROM LAKE MICHIGAN. && PREV DISCUSSION...ISSUED 430 PM EDT JUN 1 2007 .SHORT TERM (TONIGHT AND SAT)... MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS INDICATED A CLOSED MID/UPPER LEVEL OVER CNTRL SD AND A RDG FROM THE OH VALLEY THROUGH THE CNTRL GREAT LAKES. A PROMINENT SHORTWAVE SPOKE OVER ERN IA SUPPORTED AN AREA OF SHRA/TSRA FROM SE MN THROUGH SW WI INTO WRN IL. ISOLD SHRA/TSRA HAVE ALSO DEVELOPED NEAR KIMT IN AN AREA OF WEAK LOW LVL CONV WHERE SBCAPE VALUES HAD CLIMBED TO AROUND 600 J/KG...PER LAPS ANALYSIS AND MODIFIED SOUNDINGS. OTHERWISE...CU FIELD REVEALED A WELL DEFINED LAKE BREEZE BOUNDARIES IN WEAK LOW LEVEL EASTERLY FLOW PATTERN. TONIGHT...WITH LOSS OF DIURNAL HEATING...THE ISOLD SHRA OVER SRN UPPER MI SHOULD DISSIPATE. HOWEVER...SCT SHRA ASSOCIATED WITH THE IA SHORTWAVE WILL MAY MOVE INTO THE SW PORTION OF THE CWA BY LATE THIS EVENING. EXTRAPOLATION OF SHRTWV MOVEMENT AND MDLS CONSENSUS TIMING WOULD BRING THE BULK OF THE PCPN ASSOCIATED WITH THE SHRTWV THROUGH UPPER MI BTWN 06Z-12Z. SINCE THIS FEATURE SHOULD PIVOT MAINLY NORTHWARD...LOWER OR NO POPS EXPECTED OVER THE ERN CWA. ALTHOUGH WEAK MID LEVEL LAPSE RATES NEAR 5 C/KM AND LITTLE/NO ELEVATED CAPE WOULD NOT FAVOR TSTMS AT LEAST ISOLD TSRA ARE POSSIBLE GIVEN THE STRENGTH OF THE SHRTWV. GREATER CLOUD COVER OVERNIGHT SHOULD CUT DOWN ON RADIATIONAL COOLING AND FOG COVERAGE/INTENSITY. SAT...SOME LEFTOVER PCPN MAY LINGER DURING THE MORNING AS THE FIRST SHRTWV LIFTS TO THE NORTH. OTHERWISE...CONSIDERABLE CLOUDS ARE EXPECTED EVEN IF THERE IS A LULL BEFORE ANY ADDITIONAL SHRTWVS MOVE TOWARD THE AREA AS THE MID LEVEL LOW SLOWLY APPROACHES. INCREASING DEEP LAYER QVECTOR CONV AND LOW LVL CONV NEAR THE SFC TROF SHOULD SUPPORT ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. .LONG TERM (SAT NIGHT THROUGH NEXT FRI)... UPPER LOW SLOWLY FINALLY BEGINS TO SLIDE ACROSS UPPER GREAT LAKES REGION SAT NIGHT. THE LOW PROBABLY WILL NOT COMPLETELY LOSE ITS GRIP ON WEATHER OVER CWA UNTIL LATER TUE. LOTS OF CHANCE POPS AS THE LOW MOVES ACROSS. PCPN LATER SAT INTO SAT NIGHT DRIVEN BY THETA-E ADVECTION AND UPPER LEVEL DIVERGENCE. HINT OF A DRY SLOT COMING ACROSS LATER SAT NIGHT INTO FIRST PART OF SUN. HOWEVER...WITH UPPER LOW STILL TO THE WEST...CANNOT COUNT OUT SOME PCPN EVEN DURING THAT TIME AS THERE MAY BE OTHER CONVECTIVELY INDUCED SHORTWAVES LIFTING INTO UPPER MICHIGAN. LATEST NAM INDICATES ONE SUCH WAVE. DRYING ALOFT...LINGERING SFC DEWPOINTS 55-60F...AND LIGHT WINDS SHOULD LEAD TO FOG OVERNIGHT SAT NIGHT. EVENTUALLY ...DIURNAL HEATING AND LIFT FM MORE SUBSTANTIAL SHORTWAVE SHOULD INCREASE SHOWERS ACROSS AREA ON SUN. EXPECTED POSITION OF UPPER LOW AND GREATER LOW LEVEL MOISTURE FAVORS THE SOUTH INTO THE EAST CWA FOR HIGHEST POPS. TROUGH AXIS GRINDS EAST SUN NIGHT TO A POSITION CENTERED OVR NORTHERN LOWER MICHIGAN TO EASTERN UPPER MICHIGAN MON. DEFORMATION PCPN THAT IS OVR LK SUPERIOR SUN MAY SINK ACROSS EASTERN CWA SUN NIGHT INTO MON. CYCLONIC FLOW IN LOWER LEVELS WILL ALSO ENHANCE PCPN. RAISED POPS FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING WILL STEADILY WORK IN FM THE NORTHWEST WHICH SHOULD BEGIN TO END POPS OVR WEST LATE SUN NIGHT. TROUGH CONTINUES TO ONLY MOVE SLOWLY OUT OF THE REGION BY WED. THIS SLOW EJECTION IS DUE IN PART TO AN ADDITIONAL SHORTWAVE THAT DIGS INTO THE TROUGH LATE MON INTO TUE FM CENTRAL CANADA. THIS IDEA IS CONSISTENT WITH EARLIER MODEL GUIDANCE. THE REINFORCING SHORTWAVE WILL PRODUCE SMALL CHANCE OF SHOWERS ACROSS CWA MON NIGHT-TUE (ENHANCED BY DAYTIME HEATING ON TUE) AND ALSO ALLOW FOR SOME SLIGHTLY BELOW NORMAL TEMPERATURES. ONCE THE SHORTWAVE TROUGH SHIFTS TOWARD NEW ENGLAND...UPPER LEVEL FLOW FLATTENS AND MUCH WARMER AIR MAKES MOVE FM THE PLAINS INTO THE UPPER GREAT LAKES QUICKLY. NEED TO KEEP EYE ON TUE NIGHT AS RADIATIONAL COOLING MAY BE FURTHER ENHANCED AS PWAT MINIMUM DRIFTS ACROSS. TRENDED IN DIRECTION OF COOP MOS WHICH SHOWED FAVORED COLD SPOTS INTO THE LOWER-MIDDLE 30S. RECORDS FOR THIS DATE SOLIDLY IN THE 20S...EVEN AN UPPER TEENS READING AT CHAMPION. SO...AROUND 30 INTO LWR 30S NOT OUT OF THE REALM OF POSSIBILITY. THE SUBSTANTIAL WARM AIR ADVECTION WED-THU COULD TRIP OFF SOME SHOWERS OR THUNDERSTORMS LATE WED INTO THU. HPC FAVORED 00Z/12Z ECMWF GUIDANCE SUGGESTS BETTER CHANCES OF PCPN THU JUST AHEAD OF WELL DEFINED NORTHERN STREAM SHORTWAVE. ON THE OTHER HAND... 00Z/06Z/12Z GFS AND CANADIAN SHOW A MUCH MORE SLUGGISH SYSTEM FOR LATE WEEK WITH RAIN POSSIBILITY LINGERING INTO FRI. ZONAL FLOW EXPECTED...SO WILL GO WITH HPC/ECWMF SOLUTION AND HAVE A DRY FCST NEXT FRI. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DISCUSSION...JLB/JLA MARINE...KF AVIATION...GM/KF mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1250 AM EDT SAT JUN 2 2007 .AVIATION (FOR 06Z TAFS)... TOUGH FORECAST COMING UP WITH LOW CLOUDS AND FOG TO KCMX AND HIGH CLOUDS AT KSAW. FEELING IS MORE OF THE SAME WILL CONTINUE WITH LOW CLOUDS AND FOG BEING ADVECTED INTO KCMX OVERNIGHT WITH EAST WINDS. LIFR CEIGS AND VIS...AND DO NOT SEE ANY IMPROVEMENTS THERE AS WINDS WILL CONTINUE TO ADVECT OFF LAKE SUPERIOR. LIFR CEIGS AT KSAW EXPECTED AS RAIN MOVES IN...POSSIBLY GOING TO MVFR WITH SOUTH WINDS...ALONG WITH THE SMALL CHANCE OF INCREASED FOG IF ITS ABLE TO ADVECT IN FROM LAKE MICHIGAN. && PREV DISCUSSION...ISSUED 430 PM EDT JUN 1 2007 .SHORT TERM (TONIGHT AND SAT)... MAIN FCST CONCERNS ARE SHRA/TSRA TRENDS. WV IMAGERY AND RUC ANALYSIS INDICATED A CLOSED MID/UPPER LEVEL OVER CNTRL SD AND A RDG FROM THE OH VALLEY THROUGH THE CNTRL GREAT LAKES. A PROMINENT SHORTWAVE SPOKE OVER ERN IA SUPPORTED AN AREA OF SHRA/TSRA FROM SE MN THROUGH SW WI INTO WRN IL. ISOLD SHRA/TSRA HAVE ALSO DEVELOPED NEAR KIMT IN AN AREA OF WEAK LOW LVL CONV WHERE SBCAPE VALUES HAD CLIMBED TO AROUND 600 J/KG...PER LAPS ANALYSIS AND MODIFIED SOUNDINGS. OTHERWISE...CU FIELD REVEALED A WELL DEFINED LAKE BREEZE BOUNDARIES IN WEAK LOW LEVEL EASTERLY FLOW PATTERN. TONIGHT...WITH LOSS OF DIURNAL HEATING...THE ISOLD SHRA OVER SRN UPPER MI SHOULD DISSIPATE. HOWEVER...SCT SHRA ASSOCIATED WITH THE IA SHORTWAVE WILL MAY MOVE INTO THE SW PORTION OF THE CWA BY LATE THIS EVENING. EXTRAPOLATION OF SHRTWV MOVEMENT AND MDLS CONSENSUS TIMING WOULD BRING THE BULK OF THE PCPN ASSOCIATED WITH THE SHRTWV THROUGH UPPER MI BTWN 06Z-12Z. SINCE THIS FEATURE SHOULD PIVOT MAINLY NORTHWARD...LOWER OR NO POPS EXPECTED OVER THE ERN CWA. ALTHOUGH WEAK MID LEVEL LAPSE RATES NEAR 5 C/KM AND LITTLE/NO ELEVATED CAPE WOULD NOT FAVOR TSTMS AT LEAST ISOLD TSRA ARE POSSIBLE GIVEN THE STRENGTH OF THE SHRTWV. GREATER CLOUD COVER OVERNIGHT SHOULD CUT DOWN ON RADIATIONAL COOLING AND FOG COVERAGE/INTENSITY. SAT...SOME LEFTOVER PCPN MAY LINGER DURING THE MORNING AS THE FIRST SHRTWV LIFTS TO THE NORTH. OTHERWISE...CONSIDERABLE CLOUDS ARE EXPECTED EVEN IF THERE IS A LULL BEFORE ANY ADDITIONAL SHRTWVS MOVE TOWARD THE AREA AS THE MID LEVEL LOW SLOWLY APPROACHES. INCREASING DEEP LAYER QVECTOR CONV AND LOW LVL CONV NEAR THE SFC TROF SHOULD SUPPORT ADDITIONAL SCT SHRA AND ISOLD TSRA BY MID AFTERNOON. .LONG TERM (SAT NIGHT THROUGH NEXT FRI)... UPPER LOW SLOWLY FINALLY BEGINS TO SLIDE ACROSS UPPER GREAT LAKES REGION SAT NIGHT. THE LOW PROBABLY WILL NOT COMPLETELY LOSE ITS GRIP ON WEATHER OVER CWA UNTIL LATER TUE. LOTS OF CHANCE POPS AS THE LOW MOVES ACROSS. PCPN LATER SAT INTO SAT NIGHT DRIVEN BY THETA-E ADVECTION AND UPPER LEVEL DIVERGENCE. HINT OF A DRY SLOT COMING ACROSS LATER SAT NIGHT INTO FIRST PART OF SUN. HOWEVER...WITH UPPER LOW STILL TO THE WEST...CANNOT COUNT OUT SOME PCPN EVEN DURING THAT TIME AS THERE MAY BE OTHER CONVECTIVELY INDUCED SHORTWAVES LIFTING INTO UPPER MICHIGAN. LATEST NAM INDICATES ONE SUCH WAVE. DRYING ALOFT...LINGERING SFC DEWPOINTS 55-60F...AND LIGHT WINDS SHOULD LEAD TO FOG OVERNIGHT SAT NIGHT. EVENTUALLY ...DIURNAL HEATING AND LIFT FM MORE SUBSTANTIAL SHORTWAVE SHOULD INCREASE SHOWERS ACROSS AREA ON SUN. EXPECTED POSITION OF UPPER LOW AND GREATER LOW LEVEL MOISTURE FAVORS THE SOUTH INTO THE EAST CWA FOR HIGHEST POPS. TROUGH AXIS GRINDS EAST SUN NIGHT TO A POSITION CENTERED OVR NORTHERN LOWER MICHIGAN TO EASTERN UPPER MICHIGAN MON. DEFORMATION PCPN THAT IS OVR LK SUPERIOR SUN MAY SINK ACROSS EASTERN CWA SUN NIGHT INTO MON. CYCLONIC FLOW IN LOWER LEVELS WILL ALSO ENHANCE PCPN. RAISED POPS FOR EASTERN AREAS INTO MON. OTHERWISE...DRYING WILL STEADILY WORK IN FM THE NORTHWEST WHICH SHOULD BEGIN TO END POPS OVR WEST LATE SUN NIGHT. TROUGH CONTINUES TO ONLY MOVE SLOWLY OUT OF THE REGION BY WED. THIS SLOW EJECTION IS DUE IN PART TO AN ADDITIONAL SHORTWAVE THAT DIGS INTO THE TROUGH LATE MON INTO TUE FM CENTRAL CANADA. THIS IDEA IS CONSISTENT WITH EARLIER MODEL GUIDANCE. THE REINFORCING SHORTWAVE WILL PRODUCE SMALL CHANCE OF SHOWERS ACROSS CWA MON NIGHT-TUE (ENHANCED BY DAYTIME HEATING ON TUE) AND ALSO ALLOW FOR SOME SLIGHTLY BELOW NORMAL TEMPERATURES. ONCE THE SHORTWAVE TROUGH SHIFTS TOWARD NEW ENGLAND...UPPER LEVEL FLOW FLATTENS AND MUCH WARMER AIR MAKES MOVE FM THE PLAINS INTO THE UPPER GREAT LAKES QUICKLY. NEED TO KEEP EYE ON TUE NIGHT AS RADIATIONAL COOLING MAY BE FURTHER ENHANCED AS PWAT MINIMUM DRIFTS ACROSS. TRENDED IN DIRECTION OF COOP MOS WHICH SHOWED FAVORED COLD SPOTS INTO THE LOWER-MIDDLE 30S. RECORDS FOR THIS DATE SOLIDLY IN THE 20S...EVEN AN UPPER TEENS READING AT CHAMPION. SO...AROUND 30 INTO LWR 30S NOT OUT OF THE REALM OF POSSIBILITY. THE SUBSTANTIAL WARM AIR ADVECTION WED-THU COULD TRIP OFF SOME SHOWERS OR THUNDERSTORMS LATE WED INTO THU. HPC FAVORED 00Z/12Z ECMWF GUIDANCE SUGGESTS BETTER CHANCES OF PCPN THU JUST AHEAD OF WELL DEFINED NORTHERN STREAM SHORTWAVE. ON THE OTHER HAND... 00Z/06Z/12Z GFS AND CANADIAN SHOW A MUCH MORE SLUGGISH SYSTEM FOR LATE WEEK WITH RAIN POSSIBILITY LINGERING INTO FRI. ZONAL FLOW EXPECTED...SO WILL GO WITH HPC/ECWMF SOLUTION AND HAVE A DRY FCST NEXT FRI. && .MARINE (FOR 4 PM ISSUANCE OF LAKE SUPERIOR FCST)... GENERALLY WEAK ERLY FLOW WILL PREVAIL WITH WAVES 2 FT OR LESS EXCEPT OVER THE FAR WEST END WHERE DEVELOPING LOW PRES OVER ERN MN AND ASSOCIATED PRES FALLS ALONG WITH TOPOGRAPHIC EFFECTS WILL LEAD TO STRONGER NE WINDS AND SLIGHTLY HIGHER WAVES BY LATE TONIGHT AND SAT. SO...LEANED TOWARD THE RUC13 WHICH DISPLAYED THIS SCENARIO BEST. WITH LITTLE IN THE WAY OF DRY ADVECTION AND ADDITIONAL PCPN EXPECTED...AREA OF FOG WILL PERSIST THROUGH SAT. BY SUN...THE FASTER GFS WAS FAVORED WHICH WILL RESULT IN A TIGHTER GRADIENT AND STRONGER N WINDS ON SUN. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM/MARINE...JLB LONG TERM...JLA AVIATION...GM/KF mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL M 1200 AM CDT SAT JUN 2 2007 ...AVIATION DISCUSSION UPDATED... .PREVIOUS DISCUSSION /900 PM CDT FRI JUN 1 2007/ CURRENT RADAR INDICATING AREA OF SHOWERS AND THUNDERSTORMS ALONG MO/KS BORDER AND ALONG SOUTHERN BORDER. SUNSET AND HIGHER STABILITY FROM EARLIER CONVECTION HAS RESULTED IN A GENERAL WEAKENING OF CONVECTION AS IT MOVES INTO THE AREA. LIGHTNING DATA SHOWING THIS TREND AS WELL. STILL...DECENT THETA E ADVECTION SHOWING UP IN MODELS AHEAD OF THE COLD FRONT AND WITH FLASH FLOOD GUIDANCE GENERALLY JUST OVER HALF AN INCH FOR ONE HOUR...WILL LET FLASH FLOOD WATCH RIDE UNTIL MIDNIGHT SHIFT ARRIVES. NO OTHER SIGNIFICANT CHANGES TO GOING FORECAST AS TEMPERATURES AND WINDS ON TRACK. ADOLPHSON /339 PM CDT FRI JUN 1 2007/ MCV THAT MOVED ACROSS NORTHERN AND CENTRAL MISSOURI EARLY THIS MORNING HAS NOW PUSHED INTO EASTERN IA THIS AFTERNOON LEAVING A FAIRLY WORKED OVER BL ACROSS EASTERN KANSAS THROUGH CENTRAL MISSOURI. HOWEVER...SOME AIR MASS RECOVERY HAS TAKEN PLACE ACROSS THE AREA WITH 19Z RUC ANALYSIS SHOWING 500-1000 J/KG SBCAPE ACROSS EXTREME EASTERN KANSAS THROUGH CENTRAL MO. THIS HAS RESULTED IN WIDESPREAD CU DEVELOPMENT MAINLY ALONG AND NORTH OF A KANSAS CITY TO KIRKSVILLE LINE. A MUCH MORE UNSTABLE AIR MASS EXISTS ACROSS EASTERN OKLAHOMA INTO EXTREME SOUTHERN KANSAS WHERE SFC TDS HAVE RISEN INTO THE MID TO UPPER 60S. THIS IS COINCIDENT WITH HIGHEST THETA E WHICH THE LATEST RUC SHOWS MAKING AT LEAST SOMEWHAT OF A NORTHWARD PUSH BY THIS EVENING. RECENT REGIONAL RADAR MOSAIC REVEALING SCATTERED SHOWERS AND A FEW ISOLATED THUNDERSTORMS ACROSS CENTRAL KANSAS WITH AN OVERALL GENERAL EASTWARD PROGRESSION. MOST IMPRESSIVE CELL ATTM WAS JUST SOUTH OF WICHITA ALONG THE EFFECTIVE FRONTAL BOUNDARY LEFT FROM THIS MORNINGS CONVECTION. THIS CELL SEEMS TO BE FEEDING OFF OF RICHER THETA E AIR MASS TO ITS SOUTH DESPITE MARGINAL 0-6KM BULK SHEAR VALUES OF 30-35KTS. ACTIVITY SHOULD SPREAD SLOWLY EASTWARD DURING THE AFTERNOON AND EVENING HOURS AND LOOKS TO PUSH INTO KANSAS AND MISSOURI DURING THE NEXT SEVERAL HOURS. APPEARS ATTM THAT THE HEAVIEST RAINFALL SHOULD REMAIN ALONG AND SOUTH OF THE I70 CORRIDOR. ALSO...CANNOT RULE OUT A FEW SHOWERS/THUNDERSTORMS DEVELOPMENT WITHIN THICKENING CU FIELD ACROSS NORTHERN MO...HOWEVER WINDOW OF OPPORTUNITY FOR THE AIR MASS TO TAKE ADVANTAGE OF PEAK HEATING IS QUICKLY DIMINISHING. NEVERTHELESS...WITH MODEL DISCREPANCY CONTINUING AND FAIRLY LOW FFG VALUES ACROSS SOME OF THE NORTHERN TIER COUNTIES...OPTED TO ONLY REMOVE 7 OF THE NORTHWEST MO COUNTIES FROM THE FLASH FLOOD WATCH. OVERALL...BELIEVE SEVERE POTENTIAL WILL REMAIN FAIRLY MINIMAL WITH WORKED OVER AIR MASS. HOWEVER...FEEL ANY OPPORTUNITY WOULD EXIST ALONG AND SOUTH OF I70 CLOSER TO RICHER THETA E ADVECTION. IN ADDITION...AS MORE ROBUST CELLS NEAR WICHITA PUSH EAST NORTHEAST...DEEP LAYER SHEAR SHOULD GRADUALLY IMPROVE WITH TIME AS DEEP NORTHERN PLAINS UPPER LOW SLOWLY SLIDES EAST AND 50+ KT H5 JET STREAK SWINGS ACROSS NORTHERN KS INTO NORTHERN MO TONIGHT. WILL HAVE TO KEEP AN EYE ON THIS AREA FOR MORE VIGOROUS CONVECTIVE DEVELOPMENT THROUGH THE EVENING. NORTHERN PLAINS UPPER LOW SHIFTS INTO THE UPPER MIDWEST TOMORROW ALLOWING THE SFC COLD FRONT TO SLOWLY PUSH THROUGH THE AREA BY TOMORROW NIGHT. BELIEVE THIS MAY BE A SLOWER PROCESS THAN PREVIOUSLY THOUGHT AND HAVE THEREFORE HELD ON TO POPS...ESPECIALLY ACROSS THE SOUTHERN AND EASTERN COUNTIES THROUGH SATURDAY AFTERNOON AND EVENING. SOME WRAP AROUND SHOWERS MAY ALSO BE POSSIBLE MAINLY ACROSS NORTHERN MO SATURDAY AS CLOSED UPPER SYSTEM MAKES ITS EASTWARD PROGRESS. OTHERWISE...RAIN CHANCES SHOULD GRADUALLY DIMINISH SAT NIGHT WITH ONLY A SLIGHT CHC TO CHC POPS BY SUNDAY AS A SECONDARY VORT MAX TRAVERSES THE AREA ON THE BACK SIDE OF DEPARTED UPPER LOW. HOWEVER...DETAILS ON THIS DISTURBANCE ARE UNCLEAR AT THE MOMENT WITH CURRENT MODEL INDICATIONS AND WILL ONLY KEEP LOW POPS ATTM. DEROCHE EXTENDED (MONDAY THROUGH FRIDAY)... EVOLUTION OF THE BREAKDOWN OF A HIGH AMPLITUDE FLOW PATTERN ACROSS THE ERN PACIFIC AND WRN CONUS WILL THE PRIMARY FORECAST PROBLEM IN THE MEDIUM RANGE. MODELS ARE IN GOOD AGREEMENT FOR THE BEGINNING OF NEXT WEEK SHOWING STRONG PACIFIC JET ENERGY UNDERCUTTING THE HIGH AMPLITUDE...SHORT WAVELENGTH RIDGE EXTENDING FROM THE SRN ROCKIES TO NRN ALASKA. THIS IS WHERE ANY SEMBLANCE OF MODEL CONFIDENCE DETERIORATES RAPIDLY. GFS CONTINUITY IS RATHER POOR...WITH THE NORMALLY CONSISTENT ECMWF EVEN SHOWING GREATER THAN NORMAL FLUCTUATIONS. GFS ENSEMBLES OFFER LITTLE HELP WITH A SEASONABLY LARGE SPREAD IN SOLUTIONS BY THE END OF THE PERIOD. WEAK NWLY FLOW EARLY IN THE WEEK ASSOCIATED WITH A DEPARTING LONGWAVE TROUGH OVER THE ERN CONUS SHOULD PROVIDE TEMPERATURES VERY NEAR THEIR SEASONAL AVERAGES. GRADUAL WARMING LOOKS LIKE A GOOD BET TOWARDS THE END OF THE WEEK AS H5 HEIGHTS BEGIN TO RISE AHEAD OF THE DIGGING WRN CONUS TROUGH. IN ADDITION...WITH THE RIDGE SITUATED OVER THE ROCKIES PRIOR TO MOVING INTO THE PLAINS...FINALLY A MORE ROBUST EML WILL ADVECT INTO THE REGION WITH GFS FORECASTING +12C TO +14C H7 TEMPERATURES. WILL NEED TO WATCH FOR THE POSSIBILITY OF WAA SHOWERS AND THUNDERSTORMS TUES NIGHT AS THIS LAYER QUICKLY ADVECTS TOWARDS THE MID AND LOWER MISSOURI RIVER VALLEY. HAVE NOT RAISED POPS SUFFICIENTLY TO MENTION IN ZONES AS THETA-E AND ISENTROPIC SURFACES HINT THAT FOCUS MAY BE FURTHER NORTH INTO NEBR/IOWA. DID NOT GET TOO AGGRESSIVE ON THUNDER MENTION FOR THE END OF THE WEEK GIVEN OVERALL MODEL UNCERTAINTY. GIVEN THE SEASONAL TREND THIS YEAR...FEEL THE GFS SOLUTION OF A MORE CUTOFF FEATURE MAY BE THE BEST OPTION...HOWEVER THE PROGRESSIVE NATURE OF THIS MODEL IS MORE QUESTIONABLE...ESPECIALLY IF ONE BUYS THE CUTOFF SOLUTION. ALSO...GIVEN THE EXPECTED STRONG CAPPING INVERSION...FEEL IT WILL NECESSITATE STRONG FRONTAL CONVERGENCE AND UPPER SUPPORT TO BREAK CONVECTIVE INHIBITION. 21 && .AVIATION... BAND OF SHOWERS WITH AN ISOLATED EMBEDDED THUNDERSTORM WILL CONTINUE TO MOVE THROUGH FROM WEST TO EAST OVER THE TERMINALS. CEILINGS AND VISIBILITIES WILL BRIEFLY FALL TO MVFR CONDITIONS IN HEAVIER SHOWERS AND THUNDERSTORMS. AS LIGHT WINDS SETTLE OVER THE AREA...SOME PATCHY FOG WILL DEVELOP IN THE ST JOSEPH AREA AND BRING DOWN THE VISIBILTY TO AROUND 3 MILES UNTIL AFTER SUNRISE. ADOLPHSON DEROCHE && .EAX WATCHES/WARNINGS/ADVISORIES... MO...FLASH FLOOD WATCH UNTIL 7 AM SATURDAY FOR MOZ005-MOZ006-MOZ007- MOZ008-MOZ013-MOZ014-MOZ015-MOZ016-MOZ017-MOZ020-MOZ021- MOZ022-MOZ023-MOZ024-MOZ025-MOZ028-MOZ029-MOZ030-MOZ031- MOZ032-MOZ033-MOZ037-MOZ038-MOZ039-MOZ040-MOZ043-MOZ044- MOZ045-MOZ046-MOZ053-MOZ054. KS...FLASH FLOOD WATCH UNTIL 7 AM SATURDAY FOR KSZ025-KSZ057-KSZ060- KSZ103-KSZ104-KSZ105. $$ mo AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE OMAHA/VALLEY NE 310 AM CDT SUN JUN 3 2007 .DISCUSSION... LATEST WATER VAPOR IMAGERY AND RUC 500MB ANALYSIS SHOW UPPER LOW SPINNING OVR CNTRL IA EARLY THIS MORNING WITH AMPLIFIED RIDGE BUILDING OVER THE ROCKIES. EXPECTING SCATTERED SHOWERS TO DEVELOP AGAIN TODAY AHEAD OF VORT LOBE SPINNING AROUND COLD CORE UPPER LOW AND AS LAPSE RATES STEEPEN LATER THIS MORNING/EARLY THIS AFTERNOON. WL LINGER POPS IN THE EAST THRU 03Z AS SYSTEM EXITS INTO WI BY 00Z. HAVE GONE ON A COOLER SIDE OF MOS GUIDANCE TO ACCOUNT FOR EXPECTED CLOUD COVER TODAY. NEXT SHORTWAVE OF INTEREST IS CURRENTLY RIDING DOWN THE UPPER RIDGE OVR NRN CANADIAN PRAIRIE PROVINCES. THIS IS FORECAST TO MOVE INTO THE NRN PLAINS ON MONDAY AND PUSH A WEAK SFC FNT INTO NRN SECTIONS OF THE CWA BY MONDAY AFTERNOON. IN COLLABORATION WITH SURROUNDING OFFICES...HAVE INCREASED POPS MONDAY AFTERNOON AND EVENING AS OMEGA VALUES INCREASE AHEAD OF THIS SHORTWAVE AND COULD SEE ENOUGH FORCING TO SPARK OFF SCT SHOWERS/TSTMS MAINLY IN OUR NERN COUNTIES. NWRLY FLOW ALOFT CONTINUES INTO TUESDAY AND SHOULD BE A FAIRLY QUIET DAY WITH SFC RIDGE BUILDING ACROSS FORECAST AREA. BOTH GFS AND NAM DEVELOP MCS ACTIVITY ACROSS CNTRL NEB TUE EVENING AND SPREAD IT ESE ACROSS MUCH OF ERN NEB/SWRN IA. STRONG NOCTURNAL LLVL JET WL CONTINUE TO FEED INTO THIS MCS THRU THE NIGHT AND SHOULD HELP SUSTAIN ACTIVITY INTO WED MORNING WITH SERN NEB/NERN KS/NWRN MO SEEING HIGHEST QPF VALUES. RIVERS HAVE BEEN RUNNING HIGH IN THIS AREA AND THE MO MAIN STEM AT NEB CITY AND RULO JUST FELL BELOW FLOOD STAGE SATURDAY MORNING SO WL KEEP CLOSE EYE ON THIS EVENT AND FORECAST QPF. WK UPPER RIDGE BUILDS OVER CNTRL PLAINS LATE TUE NIGHT/WED MORNING AHEAD OF CLOSED CIRCULATION MOVING ONTO THE WA/OR COAST. STRONG RETURN FLOW SETS UP ACROSS THE FORECAST AREA WHILE LEESIDE CYCLOGENESIS TAKE PLACE ACROSS THE HIGH PLAINS. GREAT UNCERTAINTY LIES IN EXACTLY WHERE THIS CYCLONE AND ASSOCIATED WMFNT AND DRYLINE WL SET UP DURING THE DAY BUT BOTTOM LINE IS THAT WX SHOULD BE QUITE UNSETTLED WITH STRONG LLVL MOIST ADVECTION ACROSS THE CNTRL PLAINS. DID NOT CHANGE MUCH IN THE EXTENDED PERIODS. STILL LOOKS TO BE AN ACTIVE TIME AS UPPER LEVEL ENERGY MOVES ACROSS THE NWRN CONUS AND CDFNT PUSHES THRU FORECAST AREA LATE IN THE WORK WEEK. && .AVIATION... WITH MAIN SURFACE AND UPPER LOWS MOVING WELL TO THE EAST THIS MORNING...ASSOCIATED CLOUDS/SHOWERS HAVE ALSO MOVED OUT OF THE CWA OR DISSIPATED WITH SUNSET. HOWEVER A BAND OF LOW LEVEL MOISTURE WAS ROTATING SOUTH AROUND THE LOW PRESSURE SYSTEM...AND WILL SPREAD BAND OF BRIEFLY MVFR CIGS ACROSS EASTERN NEBRASKA THROUGH 12Z. CYCLONIC FLOW AROUND LOW COMBINED WITH STEEPENING LAPSE RATES MAY BRING ISOLATED SHOWERS TO FAR EASTERN NEBRASKA AFTER 18Z...BUT HAVE NOT MENTIONED IN TAFS WITH EXPECTED COVERAGE BEING ISOLATED AT BEST. BETTER COVERAGE SHOULD OCCUR TOWARD CENTRAL IOWA AND EAST. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ GRIFFIS/DERGAN ne AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE ELKO NV 220 AM PDT SUN JUN 3 2007 .SYNOPSIS...HIGH PRESSURE WILL CONTINUE TO PROMOTE WELL ABOVE NORMAL TEMPERATURES THROUGH MONDAY. THESE WARM TEMPERATURES COMBINED WITH SOME MOISTURE WILL BRING ISOLATED AFTERNOON AND EVENING THUNDERSTORMS TO MAINLY EASTERN NEVADA. A LOW PRESSURE SYSTEM MOVING INTO THE REGION BEGINNING TUESDAY WILL CAUSE A RETURN TO MUCH COOLER TEMPERATURES ALONG WITH A CHANCE OF SHOWERS. && .SHORT TERM...TODAY THROUGH MONDAY...LATEST WV IMAGERY SHOWING SOME DRIER AND MORE STABLE AIR WORKING INTO WESTERN NV EARLY THIS MORNING AHEAD OF AN UPPER TROUGH THAT IS SLOWLY APPROACHING THE WEST COAST. THIS INFLUX OF DRIER AIR WILL INHIBIT T-STORM ACTIVITY ACROSS WESTERN NV TODAY...SO EXPECTING ISOLATED AFTERNOON/EVENING T-STORM ACTIVITY TO PRIMARILY BE ACROSS OUR EASTERN ZONES. 00Z KLKN SOUNDING SHOWED A PW VALUE AROUND 0.50 OF AN INCH LAST EVENING...WHICH CERTAINLY FAVORS DRY THUNDERSTORMS TODAY. HOWEVER...CANNOT RULE OUT A FEW SPRINKLES OR A BRIEF SHOWER ACROSS NORTHERN ELKO COUNTY WHERE BOTH THE NAM12 AND RUC40 ARE FORECASTING PW`S OF 0.60-0.65 OF AN INCH. BY MONDAY...THUNDERSTORM ACTIVITY WILL BE LIMITED TO WHITE PINE AND EASTERN ELKO COUNTIES AS THIS DRIER AIR CONTINUES TO PUSH EASTWARD. TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH MONDAY AS STRONG HIGH PRESSURE REMAINS OVER THE REGION. MCGEE .LONG TERM...MONDAY NIGHT THROUGH SATURDAY. MODELS COMING INTO BETTER AGREEMENT WITH SYNOPTIC PATTERN ACROSS CWA WHICH WILL BE ACTIVE FOR THE EXTENDED. THE MAIN DIFFERENCES COME WITH TIMING OF EACH TROUGH. THE GFS IS THE FASTEST MODEL WHILE THE ECMWF AND CANADIAN ARE ACTUALLY PRETTY CLOSE WITH FEATURES. WILL LEAN TOWARD THE ECMWF AND CANADIAN SOLUTION FOR THIS FORECAST. SOUTHWESTERLY FLOW WILL BE INCREASING AHEAD OF TROUGH MONDAY NIGHT INTO TUE. EXPECT AT LEAST SOUTHERN AND EASTERN PORTIONS OF CWA WILL BE WINDY AND DRY ENOUGH FOR RED FLAG CONDITIONS TO POSSIBLY BE MET WHILE COLD FRONT WILL BE MOVING THROUGH WESTERN HALF OF CWA DURING THE AFTERNOON. MODELS NOT SHOWING MUCH INSTABILITY TUE...BUT GIVEN STRENGTH OF FRONT...THINK THUNDER IS STILL A DEFINITE POSSIBILITY AND WILL LEAVE MENTION OF DRY THUNDERSTORMS SOUTH AND WET NORTH. COOLER AND MORE STABLE CONDITIONS EXPECTED FOR THE MIDDLE OF THE WEEK. LOOKS LIKE AREA WILL BE BETWEEN SYSTEMS ON WED BUT HIGHS WILL LIKELY STRUGGLE TO GET MUCH WARMER THAN THE UPPER 60S TO MID 70S. NEXT DISTURBANCE WILL ROUND BASE OF UPPER LOW OVER THE PAC NW SOMETIME THU AND SLOWLY MOVE ACROSS NORTHERN NV FRI AND BRING ANOTHER CHANCE FOR SOME SHOWERS. THINK BEST CHANCE FOR PRECIP DURING THIS PERIOD WILL BE NORTH OF HWY 50. TEMPERATURES WILL CONTINUE TO BE COOLER THAN THE LAST WEEK WITH NEAR TO SLIGHTLY BELOW AVERAGE TEMPERATURES EXPECTED DEPENDING ON CLOUD COVER. DRIER AIR EXPECTED TO MOVE IN FOR SAT BUT NEXT TROUGH WILL BE MOVING ONSHORE AND CWA WILL LIKELY START TO FEEL THE EFFECTS FROM THIS ONE SAT NIGHT INTO SUN. JMG && .AVIATION...ISOLATED THUNDERSTORMS ARE AGAIN EXPECTED ACROSS NORTHERN AND CENTRAL NV THIS AFTERNOON AND EVENING...BUT SHOULD REMAIN FOCUSED ALONG AND EAST OF A KBAM-KTPH LINE. AGAIN WIND GUSTS IN EXCESS OF 40KTS CAN BE EXPECTED AROUND ANY OF THESE THUNDERSTORMS. JMG && .FIRE WEATHER...AN INFLUX OF DRIER AIR WILL INHIBIT T-STORM ACTIVITY ACROSS WESTERN NV TODAY...SO EXPECTING ISOLATED AFTERNOON/EVENING T-STORM ACTIVITY TO BE LIMITED TO THE EASTERN HALF OF THE STATE. BY MONDAY...THUNDERSTORM ACTIVITY WILL BE LIMITED TO WHITE PINE AND EASTERN ELKO COUNTIES. TEMPERATURES WILL REMAIN WELL ABOVE NORMAL THROUGH MONDAY AS STRONG HIGH PRESSURE REMAINS OVER THE REGION. A STRONG LOW PRESSURE SYSTEM MOVING ONTO THE WEST COAST TUESDAY WILL BRING INCREASING WINDS TO NORTHERN AND CENTRAL NV. AT THIS TIME IT APPEARS LIKE FIRE WEATHER ZONES 455 AND 457 WILL MEET RED FLAG CRITERIA FOR WINDS AND RH...SO DAYSHIFT WILL PROBABLY BE ISSUING A FIRE WEATHER WATCH FOR TUESDAY. MCGEE && .LKN WATCHES/WARNINGS/ADVISORIES...NONE. $$ nv AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 938 AM CDT SUN JUN 3 2007 .UPDATE...DEEP MOISTURE EAST OF RED RIVER IS RETREATING TOWARDS SOUTHEAST AT 10 KNOTS WHICH WOULD CLEAR THE SHOWERS FROM CWA AT LEAST BY 18Z. SO WAS ABLE TO TRIM THE SHOWERS EASTWARD A LITTLE FROM PREVIOUS FORECAST. ALSO RAISED MAX TEMPERATURES A FEW DEGREES WHERE THE CLOUDS HAVE ALMOST CLEARED. REGIONAL RADARS SHOW THAT A SHALLOW SHORTWAVE MOVING SOUTH AT SOUTHWEST CORNER OF MB IS CAUSING A FEW SHOWERS...MOST ARE VERY LIKELY VIRGA. THIS SHORTWAVE SHOWS UP WELL AT 700 MB IN RUC AND GFS. IT WAS ABSENT IN 06Z NAM AND INITIALIZED IT AT 12Z THEN WASHED IT OUT BY 18Z. MODELS ARE STILL SHOWING SEVERAL HUNDRED J/KG OF BL CAPE THIS AFTERNOON WHILE MOST OF THE AREA WILL REACH THE CONVECTIVE TEMEPRATURE IN THE UPPER 70S. ISOLATED THUNDER STILL LOOKS PROBABLE. DVL BASIN APPEARS THE MOST LIKELY TO FIRE UP STORMS SINCE THEY WILL BE ABOVE THE CONVECTIVE TEMPERATURE THE LONGEST (STARTING ABOUT 18Z) BUT THE SHORTWAVE WILL HELP LIFT AREAS FARTHER WEST MORE. && .PREV DISCUSSION... /ISSUED 430 AM CDT SUN JUN 3 2007/ SHORT TERM... UPPER LEVEL LOW OVER SOUTHERN MN WILL MOVE EAST. ANOTHER UPPER LOW OVER NORTHERN CANADA WILL MOVE SOUTH AND ESTABLISH OVER HUDSON BAY WITH WAVE ROTATING AROUND SYSTEM. RIDGE BUILDING WILL OCCUR OVER INITIALLY WESTERN CANADA AND THE WESTERN US THEN DEVELOP AN OMEGA BLOCK OVER NORTHWEST CANADA. RIDGE BUILDING OVER THE WESTERN US WILL SHIFT EAST BY END THIS PERIOD AS UPPER LOW UNDERCUTS RIDGE IN THE WESTERN US. FOG LOOP SHOWS WEST EDGE OF CLOUD DECK RUN FROM NEAR ROX TO FINGAL ND. PRECIPITATION UNDER 700 HPA THETA-E RIDGE WILL MOVE OUT OF THE SOUTHEAST ZONES THIS MORNING. HOWEVER AFTERNOON HEATING MAY PRODUCE SCATTERED SHOWERS. SUBSIDENCE MAY KILL THREAT OF PRECIP. WILL KEEP CHANCE OF PRECIP FOR TODAY. LONG TERM... LOWERED TEMPS FOR THU. AVIATION... VFR CIGS OVER THE SOUTHEAST HALF OF THE FORECAST AREA SHOULD MOVE OUT BY EARLY AFTERNOON. HOWEVER AFTERNOON HEATING WILL CREATE SCT-BKN VFR CIGS OVER MUCH OF THE AREA THIS AFTERNOON. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...AREAL FLOOD WARNINGS FOR SARGENT...RANSOM...RICHLAND COUNTIES. MN...AREAL FLOOD WARNINGS FOR WILKIN AND GRANT COUNTIES. && $$ GV nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 840 PM CDT SAT JUN 2 2007 OUTER BANDS OF SHRA/ISOLD T CONTINUE TO SHOW SIGNS OF WEAKENING WITH LOSS OF DAYTIME HEATING. WITH CURRENT TRENDS WILL BE ABLE TO LOWER POPS ACROSS MOST OF AREA. RUC DOING A GOOD JOB DEPICTING MID LEVEL DRYING/CLEARING WHICH IS MOVING INTO FAR NW FA SO WILL DROP POPS AFT MIDNIGHT OVER DVL BASIN AND LOWER SKY COVER SOME. WITH RECENT RAINFALL AND WEAK FLOW WILL ADD PATCHY BR TO MOST AREAS. TEMPERATURES LOOK TO BE IN GOOD SHAPE CONSIDERING CLOUD/CLEARING TRENDS SO ONLY MINOR TWEAKS THERE. && .AVIATION...ISOLD MVFR CIGS OVER FAR SOUTHEAST WITH REMAINDER OF FA VFR AND EXPECT TRENDS TO CONTINUE OVERNIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...AREAL FLOOD WARNINGS FOR SARGENT...RANSOM...RICHLAND COUNTIES. MN...AREAS FLOOD WARNINGS FOR RICHLAND AND GRANT COUNTIES. && $$ VOELKER nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND FORKS ND 340 PM CDT SAT JUN 2 2007 .SHORT TERM...RUC CAUGHT THE QUICK DEVELOPMENT OF HEAVY SHOWERS/ ISOLATED THUNDER THAT DEVELOPED FROM GFK TO ROX WITH STRONG 850 MB MOISTURE CONVERGENCE AND AMPLE 300 MB DIVERGENCE...WITHIN 2 HOURS AFTER REACHING CONVECTIVE TEMPERATURES. ANOTHER BAND IS TRYING TO DEVELOP A LITTLE EAST OF DVL BUT DOES NOT HAVE AS MUCH UPPER DIVERGENCE TO FIRE IT UP. BELIEVE THE BULK OF THUNDER WILL BE THIS AFTERNOON AND THEN A WET GROUND OVER MUCH OF THE AREA WILL TURN IT MORE TO SCATTERED SHOWERS THIS EVENING...AND MUCH OF SOUTHEAST ND AND WEST CENTRAL MN HAS NOT WARMED ENOUGH TO GET STRONG CONVECTION DUE THE ALL DAY SHOWERS THERE. RUC SHIFTS THE 850 MB MOISTURE CONVERGENCE AND SHOWERS TO SOUTH OF A FAR-FSE LINE BETWEEN 00Z-03Z AND THEN TO CWA SOUTHEAST FRINGE BY 06Z. HEAVY OVERNIGHT RAIN ACROSS EXTREME PARTS OF SOUTHEAST ND AND WEST CENTRAL MN PROMPTED AN AREAL FLOOD WARNING AND SEVERAL RIVER GAGES TO HEAD TOWARDS MAJOR FLOODING. ANY ADDITIONAL RAIN IS A CONCERN BUT SHOULD BE A HALF INCH OR LESS OVERALL TONIGHT. ON SUNDAY ENOUGH INSTABILITY AND HIGH DEW POINTS WILL REMAIN TO PROBABLY POP AT LEAST ISOLATED SHOWERS OR TSTORMS. BUT SOME DRY ADVECTION LATE IN THE DAY AND AN UPPER RIDGE ARRIVING WILL END THEM BEFORE EVENING. .LONG TERM (WED-SAT)...MODELS IN GOOD AGREEMENT WITH MID WEEK FORECASTS...RETURN FLOW WILL SET UP ACROSS THE NORTHERN PLAINS ON WEDNESDAY INTO THURSDAY IN RESPONSE TO A LOW PRESSURE SYSTEM IN THE HIGH PLAINS. INCREASED POPS ON THURSDAY AS SYSTEM MOVES ACROSS THE AREA... LOOKS TO BE FAIRLY PROGRESSIVE AND EXITS THE REGION FRIDAY... THUS REMOVED POPS FRI/SAT. TEMPS APPEARED TO BE ON TARGET SO NO CHANGES. && .AVIATION...GENERALLY VFR ACROSS THE AREA... HOWEVER INCREASING CU DEVELOPMENT WILL PROVIDING SHOWERS AND THUNDERSTORMS TO THE AREA LEADING TO MVFR. LIKE THE PAST FEW DAYS SHOWERS WILL CONTINUE UNTIL LOSS OF DAYTIME HEATING AND AGAIN WILL BE POSSIBLE ON SUNDAY. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...AREAL FLOOD WARNINGS FOR SARGENT...RANSOM...RICHLAND COUNTIES. MN...AREAS FLOOD WARNINGS FOR RICHLAND AND GRANT COUNTIES. && $$ GV/JK nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 119 PM EDT SUN JUN 3 2007 .SYNOPSIS... A COLD FRONT PUSHING EAST THROUGH THE OHIO VALLEY WILL INTERACT WITH A MOIST AND UNSTABLE AIR MASS TODAY AND MONDAY. COOLER AND DRIER AIR WILL WORK INTO THE REGION ON TUESDAY. && .NEAR TERM /THROUGH TONIGHT/... OTHER THAN JUST SOME -SHRA NORTHWEST OF CMH METRO...FCST AREA PCPN FREE ATTM. CONVECTION ASSOCD WITH VORT THAT AFFECTED MUCH OF ERN FCST AREA EARLIER THIS MRNG HAS NOW MOVED INTO NRN OHIO. RAIN GAUGE ANALYSIS OVER SOUTH CNTRL OH INDCG THIS BROUGHT SOME BENEFICIAL RAINS FROM SCIOTO CO NORTH INTO ROSS AND PICKAWAY COS WITH SVRL LOCATIONS RECEIVING 1-2 INCHES. FAIRLY THICK MID LVL DECK ACRS FCST AREA THIS MRNG WAS HAMPERING WARMING...WITH TEMPS MAINLY IN THE L/M70S. FCST AREA IS IN A LULL BUT EXPECT CONVECTION TO FIRE THIS AFTN AS COLD FRONT CURRENTLY OVER WESTERN INDIANA APPCHS WESTERN FCST AREA BY LATE AFTN. CURRENT RUC ANALYSIS INDCG NICE LO LVL CONV AXIS DVLPG IN TANDEM WITH A SHOT OF MID LVL PVA AHEAD OF FRNTL BNDRY BY 20-21Z ACRS WESTERN FCST AREA. CURRENT VIS SAT INDCG BREAKS IN AC AS CLOSE AS KIND AND KSDF...AND EXPECT THERE MAY BE A LITTLE BIT OF SUNSHINE ACRS WESTERN 1/2 FCST AREA WITHIN THE NEXT FEW HOURS. THIS WILL CONTRIBUTE AVAIL INSTABILITY...WITH 500-1000 J/KG MLCAPE DVLPG BY MID AFTN. THIS IS ALL POINTING TO QUICK CONVECTIVE DVLPMNT ACRS WESTERN COUNTIES DURING THE AFTN AND SHIFTING EAST ACRS REST OF THE FCST AREA. HAVE ADJUSTED POPS A BIT TO ALIGN WITH THIS THINKING...WITH LKLY TO CAT POPS WARRANTED BY MID/LATE AFTN. MAX DELTA THETA-E VALUES ARE A BIT LOWER TODAY THAN SAT AND WITH CLOUDS SUPPRESSING HEATING...SVR POTENTIAL CONTINUES TO LOOK ISOLD THIS AFTN. EXPECT THERE WILL BE SOME STRONG STORMS WITH GUSTY WINDS AND VERY HEAVY RAINFALL (AND MUCH NEEDED AT THAT) AS MAIN THREATS...AS PROGGED STORM MOTION REMAINS ~10KTS. SLIGHTLY BETTER BL SHEAR VALUES AND FORCING ASSOCD WITH FRNTL BNDRY SHOULD ENSURE A LITTLE BETTER ORGANIZATION TO STORMS AND ALLOW THEM TO LAST WELL INTO THE EVNG HOURS. STORMS SHOULD DIE DOWN OVERNIGHT AS FORCING WEAKENS AND INSTABILITY DIMINISHES. ZONE AND GRID UPDATES WILL BE OUT SHORTLY. RYAN && .SHORT TERM /MONDAY THROUGH TUESDAY/... H5 LOW BEGINS TO FILL SUN NGT INTO MON. THE SYSTEM IS STILL ORGANIZED ENUF TO SWING H5 S/W ACROSS THE OH VLY MONDAY. THIS SHOULD KICK OFF ANOTHER ROUND OF TSTM ON MONDAY. THE BACK AND OF THE SYSTEM SHOULD BE PUSHING THRU TUE MRNG. REGION REMAINS IN NW ON TUE...BUT WEAK SFC HI BUILDS IN TUE AFTN...WHICH SHOULD HELP END THE PCPN. DIDNT STRAY TOO FAR FORM MAV MOS TODAY THRU MON NGT. WENT WITH THE WARMER MET HIGH FOR TUE. SITES && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... UPPER LEVEL FLOW TRANSITIONS TO A NWRLY FLOW PATTERN BRIEFLY WITH A SFC RIDGE BLDG IN TUE NIGHT INTO WED. THIS WL ALLOW FOR DRY WX AND MORE SEASONABLY TEMPS. THESE SEASONABLE TEMPS WL BE SHORT LIVED WITH A SOUTHERLY FLOW DEVELOPING ON THE BACKSIDE OF THIS HIGH ON THU. UPPER LEVEL RIDGE TO RE-ESTABLISH ITSELF FROM THE SE THRU THE GREAT LAKES ON THURSDAY. SHORT WAVE TO TRACK INTO THE GREAT LAKES FRI/SAT FLATTENING OUT THE NRN PORTION OF THE RIDGE. A SFC COLD FRONT TO DROP SE INTO THE OHIO VALLEY AND LAY OUT E-W AND WEAKEN AS IT ENCOUNTERS THE UPPER LEVEL RIDGE. WL THEREFORE CONTINUE A CHC OF THUNDERSTORMS ON FRIDAY AND SAT. GENERALLY PREFER TEMPS AT OR A LTL ABOVE MEX GUID THRU THE PERIOD. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... FCST AREA REMAINS UNDERNEATH AC/CI SHIELD FROM REMNANTS OF BARRY. CLOUDS ARE THINNING THOUGH...AND WDLY SCT CONVECTION HAS BEGUN TO FIRE JUST WEST OF REGION ACRS CNTRL/NRN INDIANA WHERE THERE IS GREATER INSTABILITY DUE TO MORE SUNSHINE. COLD FRONT EXTNDG SOUTH FROM NRN ILLINOIS INTO WRN KY/TN. ATMOSPHERE PROGGED TO BECOME MORE UNSTABLE AS AFTN PROGRESSES. NICE LO LVL CONV AND MID LVL PVA AXIS SET UP OVER WESTERN FCST AREA BY LATE AFTN. THIS COMBINED WITH INCREASING FORCING DUE TO APPCHG FRNTL BNDRY WILL ENABLE SCT TO NMRS TSTMS TO DVLP ACRS TERMINALS. HAVE INSERTED VCTS AT ALL TAF SITES BY LATE AFTN...AND INTRODUCED FOUR HOUR TEMPOS WHEN TSTM COVERAGE SHOULD HAVE THE GREATEST IMPACT AT EACH TERMINAL. KCVG/KLUK/KDAY WILL BE AFFECTED INITIALLY BY 20-21Z WITH ACTIVITY SPREADING EAST TO AFFECT KILN/KCMH/KLCK INTO THE ERLY EVNG. GUSTY WINDS WILL BE POSSIBLE WITHIN TSTMS. FRNTL BNDRY BECOMES RATHER DIFFUSE AS IT MOVES INTO FCST AREA OVERNIGHT. FORCING DECREASES SUBSTANTIALLY WITH INSTABILITY DIMINISHING LATE TONIGHT. THIS SHOULD KEEP DRY WX AT THE TERMINALS FROM LATE EVNG ON OTHER THAN A RENEGADE -SHRA. CU/SC MAY SCATTER OUT AFT MIDNIGHT...PARTICULARLY AT KCVG AND KLUK AS DRIER AIR BRIEFLY WORKS INTO REGION. LESS CLOUDS AND LIGHT WINDS SHOULD PROMOTE MVFR VSBY RESTRICTIONS AT ALL TERMINALS NEAR DAYBREAK...WITH POTENTIAL FOR IFR VSBYS AT KLUK. UPR LO WILL SLOWLY MOVE EAST INTO SW LOWER MICHIGAN ON MONDAY AS SFC LO INTENSIFIES OVER CNTRL GRT LKS. WEAK LO LVL CAA AND STEEPENING LAPSE RATES WILL ALLOW FOR SCT/BKN CU TO DVLP QUICKLY MON MRNG. SCT CONVECTION WILL DVLP AGAIN BUT SHOULD NOT AFFECT TERMINALS UNTIL AROUND OR AFT 18Z MON. THUNDERSTORMS ARE POSSIBLE MONDAY AFTERNOON/EVENING INTO EARLY TUESDAY...AND AGAIN ON FRIDAY. RYAN && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON OH 202 AM EDT SUN JUN 3 2007 .SYNOPSIS... A WARM HUMID AIRMASS WILL REMAIN ACROSS THE OHIO VALLEY THIS WEEKEND. A COLD FRONT OVER WILL PUSH INTO ILLINOIS TONIGHT...THEN INTO OHIO BY SUNDAY NIGHT. THE FRONT WILL ACT AS A FOCUS FOR MORE WIDESPREAD SHOWERS AND THUNDERSTORMS. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... WSR-88D CONTINUES TO SHOW CONVECTION DISSIPATING ACROSS THE ILN FORECAST AREA. AXIS OF CONVECTION THAT THAT HAS EXTENDED NE THROUGH INDIANA HAS ALSO BEEN WEAKENING WITH THE LOSS OF DAYTIME HEATING. WITH LACK OF ANY REAL ORGANIZED FORCING...HAVE DROPPED POPS IN MOST LOCATIONS DURING THE REMAINDER OF THE OVERNIGHT HOURS. RUC CONTINUES TO INDICATE SOME MID-LEVEL FORCING ROTATING NORTHWARD INTO THE EASTERN PART OF OUR FORECAST AREA LATER TONIGHT. FEEL ENOUGH UNCERTAINTY WITH THIS FEATURE IN HELPING TO INITIATE CONVECTION THAT ONLY A SLIGHT CHANCE POPS PROVIDED FOR OUR EAST FOR MAINLY LATER TONIGHT. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM MONDAY/... WITH SURFACE LOW PROVIDING CONVERGENCE AND LIFT...COUPLED WITH ADDITIONAL COOLING ALOFT...THUNDERSTORMS WILL BE LIKELY ON SUNDAY. A MODEST AMOUNT OF SEVERE THUNDERSTORMS MAY OCCUR...WITH RATHER WEAK WIND FIELDS THE LIMITING FACTOR. REMNANTS OF TS BARRY WILL SLOW THE PROGRESS OF THE SYSTEM MOVING IN FROM THE WEST...WHICH WILL INCREASE THE DURATION OF THE EVENT. THOUGH SHOWERS WILL BE LIKELY MONDAY...INSTABILITY WILL DECREASE DUE TO LOWER SURFACE TEMPERATURES. THE RESULT WILL BE NUMEROUS SHOWERS WITH A FEW THUNDERSTORMS. AFTER TWO WEEKS OF ABOVE NORMAL TEMPERATURES WHICH HAVE MADE IT FEEL MORE LIKE JULY THAN LATE MAY/EARLY JUNE...READINGS WILL FALL BACK TO NEAR NORMAL. KEPT FORECAST SLIGHTLY ABOVE GUIDANCE WHICH MAY BE BRINGING IN THE COOLER AIR TOO QUICKLY. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... UPPER TROF WL LINGER OVER THE GREAT LAKES EARLY IN THE FCST PERIOD AS REMNANTS OF THE SE TROPICAL SYSTEM TRACKS THRU THE NE US. A SFC COLD FRONT PASSING THRU THE OH VALLEY WL PROVIDE CLOUDS AND A CHANCE OF THUNDERSTORMS IN THE MONDAY NIGHT/TUE TIME FRAME. UPPER LEVEL FLOW TRANSITIONS TO A NWRLY FLOW PATTERN BRIEFLY WITH A SFC RIDGE BLDG IN TUE NIGHT INTO WED. THIS WL ALLOW FOR DRY WX AND MORE SEASONABLY TEMPS. THESE SEASONABLE TEMPS WL BE SHORT LIVED WITH A SOUTHERLY FLOW DEVELOPING ON THE BACKSIDE OF THIS HIGH ON THU. UPPER LEVEL RIDGE TO RE-ESTABLISH ITSELF FROM THE SE THRU THE GREAT LAKES ON THURSDAY. SHORT WAVE TO TRACK INTO THE GREAT LAKES FRI/SAT FLATTENING OUT THE NRN PORTION OF THE RIDGE. A SFC COLD FRONT TO DROP SE INTO THE OHIO VALLEY AND LAY OUT E-W AND WEAKEN AS IT ENCOUNTERS THE UPPER LEVEL RIDGE. WL THEREFORE CONTINUE A CHC OF THUNDERSTORMS ON FRIDAY AND SAT. GENERALLY PREFER TEMPS AT OR A LTL ABOVE MEX GUID THRU THE PERIOD. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... A LITTLE MORE TO GO OFF OF THIS MORNING WITH THUNDERSTORM ACTIVITY EXPECTED TO INCREASE THROUGH THE DAYLIGHT HOURS. H5 VORT WORKING DUE N INTO ERN OH FROM THE REMNANTS OF BARRY MAY SPARK A FEW STORMS JUST E OF SCIOTO VALLEY EARLY TODAY. THIS WILL PROBABLY NOT WORK INTO CWA AS THERE IS A SLIGHTLY UNFAVORABLE AREA OF DOWNWARD MOTION BETWEEN THE SOUTHERN SYSTEM AND THE ONE WORKING IN FROM THE WEST LATER IN THE DAY. TO THE WEST...A H5 LOW WILL TRACK TOWARDS CHITOWN AS A SFC LOW AND SOUTHWARD EXTENDING COLD FRONT MOVES INTO THE OHVLY JUST AHEAD OF IT THIS AFTERNOON AND EARLY EVENING. A LINE OF THUNDERSTORMS WILL LIKELY TRACK FROM WEST TO EAST...WITH MODELS STARTING OVER WESTERN TAF SITES AROUND 18Z...WORKING INTO ERN TAF SITES AFTER ABOUT 0Z. H5 LOW SPINS SOME VERY DRY AIR INTO THE REGION FROM SW-NE AFTER 0Z TONIGHT...PARTICULARLY ABOVE 5KFT. NO SIGNIFICANT WEATHER IS EXPECTED OUTSIDE OF THUNDERSTORM ACTIVITY THROUGH THURSDAY. FRANKS && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OH 1021 AM EDT SAT JUN 2 2007 .SYNOPSIS... LOW PRESSURE OVER THE PLAINS STATES WILL MOVE SLOWLY EAST AND THE ASSOCIATED WEAK COLD FRONT WILL CROSS THE AREA SUNDAY. A STRONGER COLD FRONT FROM THE NORTHWEST WILL CROSS THE LOWER GREAT LAKES ON TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LATEST VIS SAT THIS MORNING SHOWING CLEAR SKIES ACROSS THE ENTIRE FORECAST AREA. SOME CLOUDS AND SHOWERS/SPRINKLES MOVED THROUGH NW PA EARLIER THIS MORNING WITH A WEAK VORT MAX...BUT THAT HAS SINCE MOVED EAST AWAY FROM THE AREA. WITH THAT UPDATED TO REMOVE SLGT CHC MENTION OF PRECIP DURING THE MORNING HOURS. DESPITE CLEAR SKIES ACROSS THE AREA AS OF MID MORNING...EXPECTING SKIES CU TO DEVELOP AS WE GO THROUGH THE MIDDAY AND EARLY AFTERNOON HOURS ACROSS THE AREA. THE CLEAR SKIES HAVE ALLOWED TEMPS TO QUICKLY CLIMB ACROSS THE AREA INTO THE UPPER 70S WITH A FEW LOCATIONS ALREADY READING 80 AS OF 10 AM. DEWPOINTS ALSO IN LOWER 60S. INCREASING TEMPS ALONG WITH GOOD MOISTURE ALREADY IN PLACE WILL INCREASE INSTABILITY AROUND THE AREA INTO THE AFTERNOON. AS PREVIOUS DISCUSSION MENTIONED WITH CAPES BETWEEN 1500 AND 2000 J/KG AND LI/S -2 TO -5 CONTINUED WITH 30-40 POPS ACROSS ENTIRE FORECAST AREA THROUGH AFTERNOON. WITH ACTIVITY BEING CONVECTIVE WANTED TO KEEP POPS IN CHANCE CATEGORY AT THIS TIME. WILL MONITOR DEVELOPMENT THROUGH EARLY AFTERNOON TO SEE HOW WIDESPREAD ACTIVITY BECOMES...BUT AT THIS TIME WILL STICK WITH THE CHC POPS. TEMPS IN UPPER 80S TO AROUND 90 FOR WESTERN ZONES LOOKS GOOD FOR THIS AFTERNOON. ALONG LAKESHORE OF FAR NE OH AND NW PA TEMPS WILL CONTINUE TO CLIMB QUICKLY THIS MORNING...BUT MAY LEVEL OUT IN MID 80S THIS AFTERNOON AS WIND BECOMES A BIT ONSHORE. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/... DEEPENING UPPER LEVEL LOW PRESSURE SYSTEM AND ASSOCIATED SURFACE LOW PRESSURE SYSTEM WILL CONTINUE TO PUSH EAST SLOWLY SUNDAY AND SUNDAY NIGHT. FORECAST AREA WILL REMAIN IN THE MOIST AND UNSTABLE WARM SECTOR UNTIL THE COLD FRONT SWEEPS ACROSS THE AREA LATE SUNDAY NIGHT OR EARLY MONDAY MORNING. ANOTHER ROUND OF SEVERE WEATHER CAN BE EXPECTED WITH THESE FEATURES IS POSSIBLE DUE TO INSTABILITY AND UPPER LEVEL SUPPORT. ACTIVITY COULD POSSIBLY LINGER INTO THE NIGHT TIME HOURS AS WELL. AMPLE FLOW OF MOISTURE EXPECTED TO STREAM NORTHEAST OUT OF THE GULF OF MEXICO PROVIDED THAT CONVECTION OVER THE GULF COAST STATES DOES NOT DEVELOP AND CUT OFF FLUX OF MOISTURE. PRECIPITABLE WATER VALUES INCREASE TO ABOUT 1.5 INCH DURING THE DAY SUNDAY. I ANTICIPATE THAT STORMS WILL LIKELY PRODUCE SOME HEAVY DOWNPOURS. LOW LEVEL JET IS AROUND 13 KNOTS SO STORMS ARE NOT ANTICIPATED TO BE SLOW MOVERS. STAYED CLOSE TO MAV GUIDANCE TEMPERATURES THROUGH THIS PERIOD AS WELL. && .LONG TERM /MONDAY THROUGH FRIDAY/... WILL HAVE TO GET UPPER LOW/TROUGH OUT OF THE AREA. MODELS TRENDING TOWARD MONDAY AS BEING THE LAST DAY WHERE SHOWERS/STORMS ASSOCD DIRECTLY WITH UPPER TROUGH/LOW WILL LINGER. ALL MODELS BRING ANOTHER STRONG SHORT WAVE AND STRONGER COLD FRONT ACROSS GREAT LAKES TUESDAY AND ATMOSPHERE WILL LIKELY STILL BE RELATIVELY WARM AND MOIST AND UNSTABLE AND WILL PROBABLY SEE ANOTHER ROUND OF SHOWERS/STORMS ON TUESDAY. GUIDANCE TEMPS LOOK A LITTLE COOL ON TUESDAY AS I DOUBT THERE WILL BE SIGNIFICANT COOLING UNTIL STRONGER FRONT PASSES AND HOPEFULLY WILL BRING A BONIFIDE CHANGE OF AIR MASS AND TUE NGT AND WEDNESDAY SHOULD BE SOMEWHAT COOLER AND LESS HUMID. TURN AROUND WILL APPARENTLY BE QUICK THOUGH AND RETURN FLOW SEEMS TO DEVELOP RIGHT AWAY THURSDAY. ECMWF FASTER BRINGING WARMER AIR BACK AND LATEST GFS COMING AROUND...WILL GO A BIT WARMER THAN GUIDANCE THURSDAY WITH TEMPS GETTING BACK INTO THE 80S AT LEAST WEST HALF. MODELS HINT AT THE CHANCE FOR A FEW WARM ADVECTION TSTORMS THURSDAY BUT WILL KEEP POPS LOW UNTIL NEXT COLD FRONT BEGINS TO APPROACH LATER THURSDAY NIGHT AND FRIDAY AND HIGHER POPS FRIDAY WITH COLD FRONT COMING IN FROM THE WEST. OF COURSE NO CONFIDENCE IN TIMING THIS FAR AHEAD BUT THAT IS THE NATURE OF THE 7 DAY DETERMINISTIC FCST AND WILL ADJUST AS NECESSARY. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... RUC ANALYSIS SHOWS A SUBTLE UPPER DISTURBANCE OVER WESTERN OHIO. THE NAM ANALYZED THIS FEATURE AND IT BECOMES A TIGGER FOR PRECIPITATION ACROSS EASTERN OHIO/NW PA THIS MORNING. LATEST IR IMAGERY SUGGEST SOME CUMULUS DEVELOPMENT IN THIS AREA SO IT SEEMS REASONABLE THAT SOME ADDITIONAL SHOWER ACTIVITY WILL POP UP IN THE NEXT HOUR OR TWO AS THE DISTURBANCE MOVES EAST WITH SOME DAYTIME HEATING. WL THEREFORE INCLUDE VCSH BY 14Z FOR THE EASTERN TAF SITES THIS MORNING. STILL EXPECT SCATTERED THUNDERSTORM ACTIVITY THIS AFTERNOON WITH THE BEST CHANCE CONTINUING OVER THE EASTERN PART OF THE FORECAST AREA. WITH LOSS OF DAYTIME HEATING THE THUNDERSTORMS SHOULD DIMINISH THIS EVENING...BUT THEN THE COLD FRONT APPROACHES FROM THE WEST LATE BRININGING ANOTHER CHANCE FOR SHOWERS OR STORMS ACROSS WESTERN OHIO LATE TONIGHT. VSBYS SHOULD ALSO LOWER TO MVFR AT ALL SITES AGAIN TONIGHT. ANOTHER LAKE BREEZE EXPECTED THIS AFTERNOON NEAR THE LAKE INCLUDING CLE AND ERI. BEST CHANCE FOR WIDESPREAD SHOWERS/STORMS WILL BE SUNDAY WITH WEAK COLD FRONTAL PASSAGE...AND AGAIN ON TUESDAY WITH A SECONDARY FRONT. && .MARINE... QUIET MORNING ON THE LAKE WITH LIGHT SOUTH WINDS. EXPECT WINDS TO TURN ONSHORE NEARSHORE AND BECOME VARIABLE OFFSHORE ONCE AGAIN THIS AFTERNOON. BETTER INSTABILITY OVER LAND TODAY WITH A WEAK DISTURBANCE SO SHOWERS AND THUNDERSTORMS MAY MOVE OVER THE WATERS FROM THE LAND AREAS THIS AFTERNOON. THE COLD FRONT WILL MOVE INTO THE REGION ON SUNDAY THIS WILL LIKELY KEEP A SOUTHERLY COMPONENT TO THE WINDS TONIGHT AND SUNDAY WITH NO LAKE BREEZE ACTIVITY. IN ADDITION...THERE WILL LIKELY BE MORE NUMEROUS SHOWERS AND STORMS ALL DAY SUNDAY. A STRONGER COLD FRONT MOVES THRU MONDAY AFTERNOON/EVENING WHICH WILL CAUSE WINDS TO TURN NW AND INCREASE TO 10-20 KT. SMALL CRAFT ADVISORY CONDITIONS ARE AT LEAST POSSIBLE MON NIGHT TUE MAINLY FOR WAVES. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...LOMBARDY NEAR TERM...ABE SHORT TERM...LOMBARDY LONG TERM...KOSARIK AVIATION...MRD MARINE...MRD oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 712 AM EDT SAT JUN 2 2007 .SYNOPSIS... HIGH PRESSURE OFF THE MID ATLANTIC COAST WILL SLIDE OUT TO SEA AS AN UPPER LEVEL LOW PRESSURE SYSTEM MOVES EAST ACROSS THE UPPER MISSISSIPPI VALLEY AND INTO THE GREAT LAKES. HAZY...WARM AND HUMID CONDITIONS WILL PERSIST ALL WEEKEND WITH SCATTERED SHOWERS AND THUNDERSTORMS POPPING UP MAINLY IN THE AFTERNOONS. TROPICAL STORM /AT LEAST THE REMNANTS OF/ BARRY WILL SLIDE UP THE EASTERN SEABOARD SATURDAY AND SUNDAY...AND IS EXPECTED TO PRODUCE RAIN FOR EASTERN PARTS OF THE STATE FROM LATE SUNDAY INTO EARLY MONDAY. THAT UPPER LEVEL LOW FROM THE WEST WILL THEN PUSH A COLD FRONT THROUGH EARLY IN THE WEEK...AND BRING TEMPERATURES BACK DOWN NEARER OR SLIGHTLY BELOW NORMAL FOR THE MIDDLE TO LATTER PART OF THE WORK WEEK. && .NEAR TERM /UNTIL 11 AM THIS MORNING/... THE LIGHT WINDS AND PARTLY CLOUDY SKIES HAVE LED TO A VERY FOGGY MORNING FOR THOSE WHO RECEIVED RAIN IN THE LAST 24 HRS. WILL BE POSTING A DENSE FOG ADVSIORY FOR ALMOST ALL OF THE AREA...AS CLOUDS IN SE LEAVING AND IT SHOULD GET MORE WIDESPREAD AND A BIT MORE DENSE THAN WHAT IT IS RIGHT NOW. FOG MAY BURN AWAY SLOWLY WITH SOME CLOUD COVER OUT THERE AND ALL NIGHT TO GET THICK...BUT EVEN WITHOUT MUCH WIND...IT SHOULD BE BETTER BY 10 OR 11 AM. ISOLATED SHOWERS MOVING INTO WESTERN MTS SEEM TO BE ALONG AN AXIS OF MSTR CONVERGENCE NOTED BY RUC. THESE SHOWERS STILL HAVE SOME INSTABILITY TO WORK WITH DUE TO COOL UPPER TEMPS AND HIGH MSTR AT THE SFC. && .SHORT TERM /11 AM THIS MORNING THROUGH SUNDAY NIGHT/... HAZY...WARM AND HUMID CONDITIONS WILL CONTINUE WITH SCATTERED STRONG /AND PERHAPS SVR OR FLOOD-PRODUCING/ PULSE TSRA AGAIN THIS AFTERNOON. TEMPS WILL BE CLOSE TO WHAT WE HAD FRI. WITH JUST AS MUCH MOISTURE AROUND...THE RESULTS SHOULD BE SIMILAR. WOULD AGAIN EXPECT WHAT FIRES UP OVER THE MOUNTAINS TO DRIFT INTO THE LOWER SUSQ/PIEDMONT LATE IN THE EVENING. LI/S WILL ALREADY BE AT OR BELOW ZERO AT 12Z...SO THINGS COULD GO ANYTIME...BUT SHOULD WAIT UNTIL NOON IN MOST PLACES. CAPES ARE PROGGED TO GET NEAR 1500J VCTY OF KUNV AND KMDT THIS AFTN. PERSISTENCE IS THEREFORE THE BEST FORECAST. TONIGHT LOOKS MUCH LIKE RIGHT NOW...IN BETWEEN THE DIURNAL CONVECTION...AND STUCK IN THE SOUP. A LITTLE THE SUBSIDENCE AROUND BARRY MAY START TO IMPACT THE REGION BY MID-DAY SUNDAY...BUT OUR REGION WILL BE CLOSE TO THE RIGHT ENTRANCE REGION OF A JET STREAK MOVING NORTH/EASTWARD ON THE EAST SIDE OF THE CUTOFF LOW THAT WILL BE ADVANCING IN FROM THE UPPER GREAT LAKES. THIS COUL MAKE MORE WIDESPREAD THUNDERSTORMS SUNDAY AFTERNOON AND EVENING OVER THE WEST AND CENTRAL MTNS. WITH ALL THE ACTIVITY WE HAVE SEEN THE PAST FEW DAYS...I HAVE KEPT LIKLIES FOR POPS IN MOST PLACES FOR SUNDAY AFTN. BARRY /WHILE HE SHOULD BE DEMOTED TO DEPRESSION OR LESS STATUS BY THEN/ IS SLATED BY TPC/HPC GUIDANCE TO BE MAKING RAINFALL OVER THE DELMARVA AND NJ AS WELL AS EASTERN PA ON SUNDAY NIGHT. THE SYSTEM MOVING IN FROM THE WEST AND BARRY COULD PUT A PINCH OF SUBSIDENCE RIGHT ON THE REGION...AND KEEP A SLOT OF DRY WX RIGHT OVER THE CENTRAL MTNS...BUT THAT IS FAR TOO CUTE AT THIS POINT. WILL ALLOW FOR SOME WIGGLE ROOM IN THE TRACK AND POSSIBLE INTERACTIONS OF BARRY WITH THE UPPER LOW AND PAINT LIKELY POPS /60-70 PCT/ OVER MOST OF THE REGION ON SUNDAY NIGHT FOR NOW. && .LONG TERM /MONDAY THROUGH FRIDAY/... NOT MUCH CHANGE IN THE LONGER TERM...RESULTING IN A MANUAL BLEND OF PREVIOUS FCAST WITH THE LATEST MODEL DATA. WHILE PHASING ISSUES WILL BE THE BIGGEST FORECAST CHALLENGE IN THE LONG- TERM...MREF DATA SHOWS ANOMALOUS 500 HPA HEIGHTS AND BLW NORMAL MSLP OVER THE REGION - WHICH WILL ULTIMATELY TRANSLATE INTO COOLER AND UNSETTLED CONDS. HAVE FAVORED THE COOLER/WETTER GUID OVERALL FROM LATE IN THE WEEKEND INTO MID WEEK...WHICH AGREES WITH THE TREND NOTED IN THE MREF 1000-850MB TEMPERATURE PLUMES. EMBEDDED S/W TROFS AND ASSOC COLD FRONTS WILL TRANSLATE THROUGH THE REGION BRINGING ALMOST DAILY CHC FOR SHOWERS AND THUNDERSTORMS THROUGH MID WEEK. MREF SHOWS HEIGHTS RETURNING BACK TO NORMAL BY LATE WEEK /THUR/ WITH TEMPS FOLLOWING SUITE. && .AVIATION /11Z SATURDAY THROUGH WEDNESDAY/... DENSE FOG WITH VISIBILITIES LESS THAN 1/4SM WILL DISSIPATE THROUGH 14Z. ALL LOCATIONS WILL RECOVER TO MVFR AND VFR CONDITIONS BY THIS TIME. WITH LITTLE MOVEMENT AND SOME WEAKENING IN THE RIDGE OF HIGH PRESSURE SITUATED ACROSS THE REGION...EXPECT ANOTHER ROUND OF SCATTERED AFTERNOON THUNDERSTORMS AFTER 18Z. DID NOT TRY TO PINPOINT TSRA ACTIVITY IN THE TAFS AS THE TREND OVER THE PAST FEW DAYS IS THAT ONLY ONE AIRFIELD ACTUALLY REPORTS TSRA. THE TRICK FOR THIS AFTERNOON IS WHICH ONE... SHOWERS AND THUNDERSHOWERS WILL STAY IN THE FORECAST THROUGH MID WEEK AS AN UPPER LEVEL TROUGH REPLACES OUR CURRENT RIDGE. THIS WILL KEEP THE AREA UNSETTLED WITH INTERMITTENT MVFR/IFR CONDITIONS. THE REMNANTS OF A TROPICAL SYSTEM MAY ALSO AFFECT PARTS OF THE FORECAST AREA LATER ON SUNDAY. && .CTP WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR PAZ005-006- 010>012-017>019-024>028-033>037-041-042-045-046-049>053- 056>059-063>066. && $$ SYNOPSIS...DANGELO/STEINBUGL NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...DANGELO/STEINBUGL AVIATION...TYBURSKI/CONNELLY pa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1045 AM EDT SUN JUN 3 2007 .SYNOPSIS... THE REMNANTS OF BARRY WILL MOVE UP THE EAST COAST TODAY. A PAIR OF COLD FRONTS WILL CROSS THE SOUTHERN APPALACHIANS FROM THE WEST LATE MONDAY AND ON TUESDAY. THE SECOND OF THESE FRONTS WILL STALL ON WEDNESDAY...AND RETURN NORTH AS A WARM FRONT ON THURSDAY...LEAVING OUR AREA IN A WARM SURFACE RIDGE FOR FRIDAY AND SATURDAY. && .NEAR TERM /THROUGH TONIGHT/... OVERALL...FORECAST APPEARS TO BE WORKING OUT REASONABLY WELL. LARGE AREA OF LIGHT RAIN/DRIZZLE IN THE DEFORMATION ZONE TO THE NW OF THE REMNANT LOW CONTINUES TO CONSTRICT...AND SHOULD TRANSLATE SLOWLY TO THE EAST AND NORTH AS THE REMNANT LOW MOVES UP THE COAST OF THE CAROLINAS THROUGH THE MIDDLE PART OF THE AFTERNOON. A RELAXING GRADIENT SHOULD KEEP WINDS UNDER CONTROL SO THE LAKE WIND ADVISORY WILL BE ALLOWED TO EXPIRE AT NOON. THROUGH THE EARLY AFTERNOON... THE EASTERN ZONES COULD GET A THUNDERSTORM IN A ZONE OF BETTER LOW LEVEL CONVERGENCE PIVOTING AROUND THE AREA NEAR MONROE. THAT WILL BE INCLUDED. OTHERWISE...THE TREND TO LOWER THE POP FROM THE WEST LOOKS GOOD BASED ON RADAR IMAGERY. THE RUC AND 12Z NAM STILL SUPPORT THE NOTION THAT WESTERN ZONES AND NE GEORGIA SHOULD BREAK OUT AND BECOME MARGINALLY UNSTABLE IN THE MID TO LATE AFTERNOON... WITH ENOUGH LOW LEVEL CONVERGENCE TO TRIGGER SCATTERED SHOWERS AND STORMS. IF THERE IS A MID COURSE CORRECTION THAT IS NEEDED...IT WOULD BE THE HIGH TEMP FORECAST OVER THE EXTREME WEST...WHERE IT IS ALREADY IN THE MID 70S. WILL BUMP UP HIGH TEMPS OVER THE FAR WEST ABOUT 3-5 DEGREES TO HANDLE THIS. FOR TONIGHT...WEAK SHORTWAVE ENERGY SHOULD ROUND THE GREAT LAKES UPPER LOW TONIGHT AND EJECT EASTWARD INTO THE NC MTNS. DIMINISHING OVERNIGHT INSTABILITY SHOULD KEEP ANY RESULTING CONVECTION FROM BECOMING WIDESPREAD...AND WESTERLY DOWNSLOPE FLOW SHOULD PRECLUDE POPS OUTSIDE OF THE MTNS. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... THE UPPER LEVEL PATTERN WILL FEATURE AN EASTERN TROUGH FOR MONDAY AND TUESDAY...WITH A WELL DEFINED SHORTWAVE MOVING THROUGH ITS BASE LATE MONDAY...AND A WEAKER SHORTWAVE MOVING THOUGH IT ON TUESDAY. COLD FRONT WILL BE ASSOCIATED WITH EACH OF THE SHORTWAVES...BUT THE SURFACE FLOW AHEAD OF THESE FRONTS WILL BE WESTERLY...LIMITING PRECIPITATION CHANCES EAST OF THE MOUNTAINS IN DOWNSLOPE FLOW. SLIGHT CHANCE POPS WILL BE CARRIED IN THE LEE IN DEFERENCE TO THE MET AND FWC GUIDANCE...WHICH WERE NOTABLY HIGHER THAN THE SINGLE DIGIT MAV POPS. INSTABILITY WILL ALSO BE LIMITED...BUT ENOUGH WILL EXISTS FOR DAYTIME AND EVENING THUNDERSTORMS...ESPECIALLY IN THE MOUNTAINS WHERE CHANCE POPS WILL BE CARRIED. MAXIMUM TEMPERATURES WILL CLIMB TO ABOVE NORMAL VALUES MONDAY IN THE WAKE OF THE REMNANTS OF BARRY...AS DOWNSLOPE FLOW OVERWHELMS HEIGHT FALLS ALOFT. ON MONDAY NIGHT THROUGH TUESDAY NIGHT WEAK COLD ADVECTION AND ADDITIONAL HEIGHT FALLS OFFSET DOWNSLOPE FLOW. THIS LEADS TO MINIMUMS NEAR NORMAL...AND A MAXIMUM TUESDAY A FEW DEGREES COOLER THAN MONDAY...THOUGH STILL ABOVE NORMAL. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... THE UPPER TROUGH OVER THE EAST IS REPLACED BY A FLAT RIDGE BY THE END OF THE WEEK. THE LATEST GFS RUN IS STILL SUPPORTIVE OF THE HPC EXTENDED FORECAST SOLUTION FROM YESTERDAY...AT LEAST THROUGH THURSDAY. A COLD FRONT STALLS OVER OUR AREA WEDNESDAY...THEN LIFTS NORTH AS A WARM FRONT ON THURSDAY. ON FRIDAY THE GFS HAS SOME ISSUED WITH LOW PRESSURE OFF THE MID ATLANTIC COAST... BUT DOWN OUR WAY IS STILL IN LINE WITH THE MANUAL PROGS...AND REMAINS SO ON SATURDAY... WITH OUR AREA IN A WARM SURFACE RIDGE CENTERED NORTHEAST OF THE BAHAMAS. LIMITED DIURNAL CONVECTION IS EXPECTED WITH AFTERNOON HEATING...WITH TEMPERATURES TRENDING TO WELL ABOVE NORMAL. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... IFR CONDITIONS SHOULD BE LIMITED TO KCLT THIS MORNING...AS RAINBAND ACTIVITY WILL LIKELY DISSIPATE FARTHER WEST. A VERY SLOW END TO THE LIGHT RAIN SHOULD OCCUR FROM SW TO NE AS THE BARRY REMNANTS PULL AWAY...AND GUSTY CONDITIONS WILL LIKELY TERMINATE AROUND NOON FOR PIEDMONT TAF SITES. STILL ANTICIPATE LOW LEVEL CONVERGENCE AREA TO SET UP IN REGION OF BEST LATE DAY HEATING TO PRODUCE SCATTERED CONVECTION KAND TO KGSP TO KAVL LATE. WESTERLY MIXING SHOULD KEEP VISIBILITY UP OVERNIGHT DESPITE PERSISTENT LOW LEVEL MOISTURE. AVIATION OUTLOOK...MVFR FOG DEVELOPMENT IS LIKELY EACH MORNING. SCATTERED AFTERNOON AND EVENING DEEP CONVECTION WILL ALSO BE POSSIBLE EACH DAY THROUGH THURSDAY. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...LAKE WIND ADVISORY UNTIL NOON EDT TODAY FOR GAZ029. NC...LAKE WIND ADVISORY UNTIL NOON EDT TODAY FOR NCZ071-072-082. SC...LAKE WIND ADVISORY UNTIL NOON EDT TODAY FOR SCZ009-011>014-019. && $$ SYNOPSIS...JAT NEAR TERM...HG/PM SHORT TERM...JAT LONG TERM...JAT AVIATION...HG sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 150 AM EDT SUN JUN 3 2007 .SYNOPSIS... THE WEAKENING CENTER OF TROPICAL DEPRESSION BARRY WILL MOVE ACROSS NORTHERN FLORIDA THIS EVENING...AND REACH COASTAL SOUTH CAROLINA EARLY SUNDAY. DEEP TROPICAL MOISTURE WILL THEN SPREAD ACROSS THE COASTAL PLAINS OF THE CAROLINAS THROUGH SUNDAY AS THE SYSTEM MOVES NORTHWARD ALONG THE CAROLINA COAST. UNSETTLED WEATHER WILL CONTINUE MONDAY THROUGH TUESDAY AS A TROUGH OF LOW PRESSURE REMAINS IN PLACE ACROSS THE REGION. A HIGH PRESSURE RIDGE WILL THEN BUILD OVER THE AREA WEDNESDAY THROUGH FRIDAY AS TEMPERATURES RETURN TO ABOVE NORMAL VALUES. && .NEAR TERM /THROUGH TODAY/... OUTER BANDS OF WEAKENING TD BARRY HAVE BECOME MORE DIFFLUENT FROM THE CENTER AS OVERALL SYSTEM TRANSITIONS INTO A NON/TROPICAL LOW. THESE ROGUE BANDS HAVE INCREASED IN RADIAL SPEED AND ARE NOW DEVELOPING INTO A DBM (DIFFLUENT BANDING OF MOMENTUM) TYPE OF PATTERN. POPS ACROSS THE SOUTHEASTERN ZONES HAVE BEEN ADJUSTED ACCORDINGLY AND BUMPED UP TO CATEGORICAL. THE LATEST RUC AND 18Z NAM12 QPF TRENDS STILL KEEP THE WESTERN ZONES OUT OF THE MAIN PRECIP SHIELD AND WILL LEAVE POPS ALONE IN THESE AREAS. SOME ISOLATED MOUNTAIN -SHRA/TS ARE STILL POSSIBLE WITH DECENT BOUNDARY LAYER UPSLOPE CONTINUING...BUT WILL EXPECT A GENERAL BACKING OF WINDS THROUGH THE OVERNIGHT TO HALT MUCH OF A PRECIP THREAT ACROSS THE HIGHER TERRAIN. EVENING TEMPERATURES HAVE BEEN ADJUSTED IN SPOTS AS WELL BASED ON COOLING PRECIP AND WILL TAKE ANOTHER LOOK LATER ON TONIGHT FOR A POSSIBLE MIN TEMP ADJUSTMENT. PROMISING GFS SOLUTION KEEPS CONSIDERABLE SHOWER ACTIVITY GOING ACRS WESTERN NC SUNDAY MORNING BEFORE SUBSIDING AIRMASS AND DOWNSLOPE FLOW SPREADS UP FROM THE SOUTHWEST. PLUME OF STEEPER LAPSE RATES AND COOLING ALOFT PROGGED TO ROTATE INTO THE WESTERN CWFA SUNDAY AFTERNOON...SO WILL KEEP TSTM CHANCES GOING THROUGH THE AFTERNOON. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... LINGERING SCATTERED CONVECTION IS EXPECTED SUNDAY EVENING ALONG WEAK SURFACE BOUNDARY THAT MOVES INTO THE AREA FROM THE TENN VALLEY. HOWEVER...IT DOES NOT APPEAR THAT THERE WILL BE MUCH SUPPORT FOR CONVECTION TO LINGER LONG PAST THE LATE EVENING HOURS. AS THE ATM DESTABILIZES MONDAY AFTERNOON...WE SHOULD SEE AT LEAST ISOLATED TO WIDELY SCATTERED CONVECTION RETURN TO THE AREA. WITH THE ESTABLISHMENT OF RELATIVELY FAST ZONAL FLOW IN THE WAKE OF BARRY/S REMNANTS...THERE WILL ACTUALLY BE A RESPECTABLE DEGREE OF WIND SHEAR ON MONDAY. THEREFORE...IT/S NOT OUT OF THE QUESTION THAT CONVECTION DEVELOPING OVER THE HIGHER TERRAIN AND/OR WITHIN LEE TROUGH COULD ORGANIZE AND MOVE OUT OVER THE PIEDMONT DURING THE AFTERNOON/ EVENING...AFFECTING A RATHER LARGE AREA. PREDICTING SUCH AN EVENT 48 HOURS IN ADVANCE WOULD REQUIRE A BIT OF WISH-CASTING ON OUR PART...SO FOR NOW WE WILL CARRY POPS IN THE 30-40 RANGE FOR MON AFTERNOON AND EVENING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... A TROUGH WILL REMAIN OVER THE EAST COAST THROUGH THE EARLY PART OF THE EXTENDED RANGE. ON TUESDAY...THE GFS ADVERTISES A SW TROUGH PASSING JUST NORTH OF THE AREA...WITH AN ASSOCIATED WEAK COLD FRONT SLIDING INTO THE REGION. HOWEVER...IT IS SOMEWHAT DISCOURAGING THAT THE GFS SEEMS NONE TOO EXCITED ABOUT PRECIP CHANCES IN OUR AREA. THE GFS MAY BE ON TO SOMETHING...AS THE LOW LEVEL FLOW MAINTAINS A STRONG WESTERLY COMPONENT FOR MOST OF THE PERIOD FROM SUNDAY EVENING THROUGH TUESDAY...A FLOW WHICH IS NOT CONDUCIVE TO GOOD MOISTURE ADVECTION. WE WILL CARRY LOW CHANCE TO SLIGHT CHANCE POPS ACROSS THE REGION TUE AND TUE EVENING. BY LATE NEXT WEEK...A MAJOR TROUGH BECOMES ESTABLISHED ACROSS THE PLAINS...FORCING A RETURN OF STRONG UPPER RIDGING ACROSS THE EASTERN STATES. THEREFORE...EXPECT ISOLATED TO WIDELY SCATTERED DIURNAL CONVECTION (AT BEST AND MAINLY OVER THE MTNS) AND MUCH ABOVE NORMAL TEMPS TO RETURN TO THE REGION BY DAY 5. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... THE HEAVIEST RAIN SHIELD ASSOCIATED WITH THE BARRY CIRCULATION WILL LIKELY AFFECT WESTERN UPSTATE TAFS...AS WELL AS KCLT...THROUGH THE EARLY MORNING HOURS. ALL LOCATIONS SHOULD STEADILY DESCEND TO MVFR CIGS...IF NOT THERE ALREADY...WITH SOME IFR LIKELY AT KCLT BY DAYBREAK. AS THE RAINBAND PIVOTS AND LIFTS NORTHEAST TODAY...CIGS WILL GRADUALLY IMPROVE TO VFR BY AFTERNOON. INSTABILITY DEVELOPING IN THE WAKE OF THE SYSTEM COULD PRODUCE SCATTERED TSRA FROM KAND TO KGSP TO KAVL LATE THIS AFTERNOON...AND A VICINITY THUNDER MENTION WILL BE CARRIED FOR NOW. CLOUDS SHOULD SCATTER AFTER 00Z THIS EVENING...BUT LOW END SHOWER CHANCES WILL CONTINUE AT KAVL AS A WEAK SHORTWAVE CROSSES THE MOUNTAINS. AVIATION OUTLOOK...MVFR FOG DEVELOPMENT IS LIKELY EACH MORNING. SCATTERED AFTERNOON AND EVENING DEEP CONVECTION WILL ALSO BE POSSIBLE EACH DAY THROUGH THURSDAY. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...SBK SHORT TERM...CSH LONG TERM...JDL AVIATION...HG sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 806 PM EDT SAT JUN 2 2007 .SYNOPSIS... THE CENTER OF TROPICAL DEPRESSION BARRY WILL MOVE ACROSS NORTHERN FLORIDA THIS EVENING...AND REACH COASTAL SOUTH CAROLINA EARLY SUNDAY. DEEP TROPICAL MOISTURE WILL THEN SPREAD ACROSS THE COASTAL PLAINS OF THE CAROLINAS THROUGH SUNDAY AS THE SYSTEM MOVES NORTHWARD ALONG THE CAROLINA COAST. UNSETTLED WEATHER WILL CONTINUE MONDAY THROUGH TUESDAY AS A TROUGH OF LOW PRESSURE REMAINS IN PLACE ACROSS THE REGION. A HIGH PRESSURE RIDGE WILL THEN BUILD OVER THE AREA WEDNESDAY THROUGH FRIDAY AS TEMPERATURES RETURN TO ABOVE NORMAL VALUES. && .NEAR TERM /THROUGH SUNDAY/... OUTER BANDS OF WEAKENING TD BARRY HAVE BECOME MORE DIFFLUENT FROM THE CENTER AS OVERALL SYSTEM TRANSITIONS INTO A NON/TROPICAL LOW. THESE ROGUE BANDS HAVE INCREASED IN RADIAL SPEED AND ARE NOW DEVELOPING INTO A DBM (DIFFLUENT BANDING OF MOMENTUM) TYPE OF PATTERN. POPS ACROSS THE SOUTHEASTERN ZONES HAVE BEEN ADJUSTED ACCORDINGLY AND BUMPED UP TO CATEGORICAL. THE LATEST RUC AND 18Z NAM12 QPF TRENDS STILL KEEP THE WESTERN ZONES OUT OF THE MAIN PRECIP SHIELD AND WILL LEAVE POPS ALONE IN THESE AREAS. SOME ISOLATED MOUNTAIN -SHRA/TS ARE STILL POSSIBLE WITH DECENT BOUNDARY LAYER UPSLOPE CONTINUING...BUT WILL EXPECT A GENERAL BACKING OF WINDS THROUGH THE OVERNIGHT TO HALT MUCH OF A PRECIP THREAT ACROSS THE HIGHER TERRAIN. EVENING TEMPERATURES HAVE BEEN ADJUSTED IN SPOTS AS WELL BASED ON COOLING PRECIP AND WILL TAKE ANOTHER LOOK LATER ON TONIGHT FOR A POSSIBLE MIN TEMP ADJUSTMENT. PROMISING GFS SOLUTION KEEPS CONSIDERABLE SHOWER ACTIVITY GOING ACRS WESTERN NC SUNDAY MORNING BEFORE SUBSIDING AIRMASS AND DOWNSLOPE FLOW SPREADS UP FROM THE SOUTHWEST. PLUME OF STEEPER LAPSE RATES AND COOLING ALOFT PROGGED TO ROTATE INTO THE WESTERN CWFA SUNDAY AFTERNOON...SO WILL KEEP TSTM CHANCES GOING THROUGH THE AFTERNOON. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... LINGERING SCATTERED CONVECTION IS EXPECTED SUNDAY EVENING ALONG WEAK SURFACE BOUNDARY THAT MOVES INTO THE AREA FROM THE TENN VALLEY. HOWEVER...IT DOES NOT APPEAR THAT THERE WILL BE MUCH SUPPORT FOR CONVECTION TO LINGER LONG PAST THE LATE EVENING HOURS. AS THE ATM DESTABILIZES MONDAY AFTERNOON...WE SHOULD SEE AT LEAST ISOLATED TO WIDELY SCATTERED CONVECTION RETURN TO THE AREA. WITH THE ESTABLISHMENT OF RELATIVELY FAST ZONAL FLOW IN THE WAKE OF BARRY/S REMNANTS...THERE WILL ACTUALLY BE A RESPECTABLE DEGREE OF WIND SHEAR ON MONDAY. THEREFORE...IT/S NOT OUT OF THE QUESTION THAT CONVECTION DEVELOPING OVER THE HIGHER TERRAIN AND/OR WITHIN LEE TROUGH COULD ORGANIZE AND MOVE OUT OVER THE PIEDMONT DURING THE AFTERNOON/ EVENING...AFFECTING A RATHER LARGE AREA. PREDICTING SUCH AN EVENT 48 HOURS IN ADVANCE WOULD REQUIRE A BIT OF WISH-CASTING ON OUR PART...SO FOR NOW WE WILL CARRY POPS IN THE 30-40 RANGE FOR MON AFTERNOON AND EVENING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... A TROUGH WILL REMAIN OVER THE EAST COAST THROUGH THE EARLY PART OF THE EXTENDED RANGE. ON TUESDAY...THE GFS ADVERTISES A SW TROUGH PASSING JUST NORTH OF THE AREA...WITH AN ASSOCIATED WEAK COLD FRONT SLIDING INTO THE REGION. HOWEVER...IT IS SOMEWHAT DISCOURAGING THAT THE GFS SEEMS NONE TOO EXCITED ABOUT PRECIP CHANCES IN OUR AREA. THE GFS MAY BE ON TO SOMETHING...AS THE LOW LEVEL FLOW MAINTAINS A STRONG WESTERLY COMPONENT FOR MOST OF THE PERIOD FROM SUNDAY EVENING THROUGH TUESDAY...A FLOW WHICH IS NOT CONDUCIVE TO GOOD MOISTURE ADVECTION. WE WILL CARRY LOW CHANCE TO SLIGHT CHANCE POPS ACROSS THE REGION TUE AND TUE EVENING. BY LATE NEXT WEEK...A MAJOR TROUGH BECOMES ESTABLISHED ACROSS THE PLAINS...FORCING A RETURN OF STRONG UPPER RIDGING ACROSS THE EASTERN STATES. THEREFORE...EXPECT ISOLATED TO WIDELY SCATTERED DIURNAL CONVECTION (AT BEST AND MAINLY OVER THE MTNS) AND MUCH ABOVE NORMAL TEMPS TO RETURN TO THE REGION BY DAY 5. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... HAVE MADE SOME ADJUSTMENTS TOWARD THE PESSIMISTIC SIDE FOR THIS PACKAGE AS THE COMBINATION OF NEAR TERM RADAR TRENDS AND THE 02/12 UTC OP GFS SOLUTION YIELDING HIGHER PCPN CHANCES FOR THE TERMINALS. HAVE GONE AHEAD AND INTRODUCED CATEGORICAL RAIN OF KCLT BY EARLY EVENING AND VCSH FOR THE UPSTATE TAFS AND KHKY BASED ON THIS THINKING. LATEST MAV GUIDANCE INDICATES HIGHER CHANCES FOR AT LEAST CIG RESTRICTIONS OVERNIGHT...ESPECIALLY ACRS NC WHERE BETTER LLVL UPGLIDE FLOW WILL DEVELOP. WIND SPEEDS WILL AVERAGE LESS THAN 10 KTS INTO TOMORROW MORNING...BUT GRADUAL BACKING WINDS FROM EAST TO NNW IS EXPECTED. AVIATION OUTLOOK...MORNING FOG AND AFTERNOON AND EVENING DEEP CONVECTION POSSIBILITIES EXIST FOR MONDAY THROUGH WEDNESDAY. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...SBK SHORT TERM...CSH LONG TERM...JDL AVIATION...JDL sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 734 PM EDT SAT JUN 2 2007 .SYNOPSIS... TROPICAL STORM BARRY WILL MOVE ACROSS NORTHERN FLORIDA THIS AFTERNOON AND EVENING...AND REACH COASTAL SOUTH CAROLINA EARLY SUNDAY. DEEP TROPICAL MOISTURE WILL THEN SPREAD ACROSS THE COASTAL PLAIN OF THE CAROLINAS THROUGH SUNDAY AS THE SYSTEM MOVES NORTHWARD ALONG THE CAROLINA COAST. UNSETTLED WEATHER WILL CONTINUE MONDAY THROUGH TUESDAY AS A TROUGH OF LOW PRESSURE REMAINS IN PLACE ACROSS THE REGION. A HIGH PRESSURE RIDGE WILL THEN BUILD OVER THE AREA WEDNESDAY THROUGH FRIDAY AS TEMPERATURES RETURN TO ABOVE NORMAL VALUES. && .NEAR TERM /THROUGH SUNDAY/... OUTER BANDS FROM REMANANTS OF TD BARRY HAVE BECOME MORE DIFFLUENT FROM THE CENTER AS THE SYSTEM TRANSITIONS INTO A NON/TROPICAL LOW. THESE ROUGE BANDS HAVE INCREASED IN RADIAL SPEED AND ARE NOW DEVELOPING INTO A DBM (DIFFLUENT BANDING OF MOMENTUM) TYPE OF PATTERN. POPS ACROSS THE SOUTHEASTERN ZONES HAVE BEEN ADJUSTED ACCORDINGLY AND BUMPED UP TO CATEGORICAL. THE LATEST RUC AND 18Z NAM12 QPF TRENDS STILL KEEP THE WESTERN ZONES OUT OF THE MAIN SHIELD AND WILL KEEP POPS ALONE IN THESE AREAS. SOME ISOLATED MOUNTAIN -SHRA/TS ARE STILL POSSIBLE WITH DECENT BOUNDARY LAYER UPSLOPE CONTINING...BUT WILL EXPECT A GENERAL BACKING OF WINDS THROUGH THE OVERNIGHT TO HALT ANY PRECIP THREAT ACROSS THE HIGHER TERRAIN. EVENING TEMPERATURES HAVE BEEN ADJUSTED IN SPOTS AS WELL BASED ON COOLING PRECIP AND WILL TAKE ANOTHER LOOK LATER ON TONIGHT FOR A POSSIBLE MIN TEMP UPGRADE. PROMISING GFS SOLUTION KEEPS CONSIDERABLE SHOWER ACTIVITY GOING ACRS WESTERN NC SUNDAY MORNING BEFORE SUBSIDING AIRMASS AND DOWNSLOPE FLOW SPREADS UP FROM THE SOUTHWEST. PLUME OF STEEPER LAPSE RATES AND COOLING ALOFT PROGGED TO ROTATE INTO THE WESTERN CWFA SUNDAY AFTERNOON...SO WILL KEEP TSTM CHANCES GOING THROUGH THE AFTERNOON. && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY NIGHT/... LINGERING SCATTERED CONVECTION IS EXPECTED SUNDAY EVENING ALONG WEAK SURFACE BOUNDARY THAT MOVES INTO THE AREA FROM THE TENN VALLEY. HOWEVER...IT DOES NOT APPEAR THAT THERE WILL BE MUCH SUPPORT FOR CONVECTION TO LINGER LONG PAST THE LATE EVENING HOURS. AS THE ATM DESTABILIZES MONDAY AFTERNOON...WE SHOULD SEE AT LEAST ISOLATED TO WIDELY SCATTERED CONVECTION RETURN TO THE AREA. WITH THE ESTABLISHMENT OF RELATIVELY FAST ZONAL FLOW IN THE WAKE OF BARRY/S REMNANTS...THERE WILL ACTUALLY BE A RESPECTABLE DEGREE OF WIND SHEAR ON MONDAY. THEREFORE...IT/S NOT OUT OF THE QUESTION THAT CONVECTION DEVELOPING OVER THE HIGHER TERRAIN AND/OR WITHIN LEE TROUGH COULD ORGANIZE AND MOVE OUT OVER THE PIEDMONT DURING THE AFTERNOON/ EVENING...AFFECTING A RATHER LARGE AREA. PREDICTING SUCH AN EVENT 48 HOURS IN ADVANCE WOULD REQUIRE A BIT OF WISH-CASTING ON OUR PART...SO FOR NOW WE WILL CARRY POPS IN THE 30-40 RANGE FOR MON AFTERNOON AND EVENING. && .LONG TERM /TUESDAY THROUGH SATURDAY/... A TROUGH WILL REMAIN OVER THE EAST COAST THROUGH THE EARLY PART OF THE EXTENDED RANGE. ON TUESDAY...THE GFS ADVERTISES A SW TROUGH PASSING JUST NORTH OF THE AREA...WITH AN ASSOCIATED WEAK COLD FRONT SLIDING INTO THE REGION. HOWEVER...IT IS SOMEWHAT DISCOURAGING THAT THE GFS SEEMS NONE TOO EXCITED ABOUT PRECIP CHANCES IN OUR AREA. THE GFS MAY BE ON TO SOMETHING...AS THE LOW LEVEL FLOW MAINTAINS A STRONG WESTERLY COMPONENT FOR MOST OF THE PERIOD FROM SUNDAY EVENING THROUGH TUESDAY...A FLOW WHICH IS NOT CONDUCIVE TO GOOD MOISTURE ADVECTION. WE WILL CARRY LOW CHANCE TO SLIGHT CHANCE POPS ACROSS THE REGION TUE AND TUE EVENING. BY LATE NEXT WEEK...A MAJOR TROUGH BECOMES ESTABLISHED ACROSS THE PLAINS...FORCING A RETURN OF STRONG UPPER RIDGING ACROSS THE EASTERN STATES. THEREFORE...EXPECT ISOLATED TO WIDELY SCATTERED DIURNAL CONVECTION (AT BEST AND MAINLY OVER THE MTNS) AND MUCH ABOVE NORMAL TEMPS TO RETURN TO THE REGION BY DAY 5. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... HAVE MADE SOME ADJUSTMENTS TOWARD THE PESSIMISTIC SIDE FOR THIS PACKAGE AS THE COMBINATION OF NEAR TERM RADAR TRENDS AND THE 02/12 UTC OP GFS SOLUTION YIELDING HIGHER PCPN CHANCES FOR THE TERMINALS. HAVE GONE AHEAD AND INTRODUCED CATEGORICAL RAIN OF KCLT BY EARLY EVENING AND VCSH FOR THE UPSTATE TAFS AND KHKY BASED ON THIS THINKING. LATEST MAV GUIDANCE INDICATES HIGHER CHANCES FOR AT LEAST CIG RESTRICTIONS OVERNIGHT...ESPECIALLY ACRS NC WHERE BETTER LLVL UPGLIDE FLOW WILL DEVELOP. WIND SPEEDS WILL AVERAGE LESS THAN 10 KTS INTO TOMORROW MORNING...BUT GRADUAL BACKING WINDS FROM EAST TO NNW IS EXPECTED. AVIATION OUTLOOK...MORNING FOG AND AFTERNOON AND EVENING DEEP CONVECTION POSSIBILITIES EXIST FOR MONDAY THROUGH WEDNESDAY. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...TJB NEAR TERM...SBK SHORT TERM...CSH LONG TERM...JDL AVIATION...JDL sc AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE MIDLAND/ODESSA TX 1017 AM CDT SUN JUN 3 2007 .UPDATE... UNSTABLE WEAKLY CAPPED ATMOSPHERE EVIDENT ACRS AREA THIS MORNING PER KMAF SOUNDING. MODIFIED 12Z KMAF SOUNDING AND FCST NAM40 SOUNDING INDICATE CAPES IN EXCESS OF 2K J/KG BY EVENING. ATTP SURFACE BOUNDARY HAS PUSHED S INTO THE TRANS PECOS WITH SFC DWPNTS GENERALLY IN THE U50S TO M60S. MSAS DATA INDICATES PRIMARY LOW LEVEL MST AXIS IS ORIENTED NW-SE JUST BEHIND AFOREMENTIONED BOUNDARY. WATER VAPOR INDICATES WELL DEFINED AND RATHER LARGE SHRTWV TROF SLOWLY MOVING E THRU W-SW NM WITH 60-70KT 3H JET MAX INTO FAR W TX. 7H-5H LR/S AROUND 8 C/KM...REFERENCED CAPES...0-6KM BULK SHEAR OF 45-50KT SUPPORTIVE OF SEVERE TSTMS. LARGE HAIL/DAMAGING WIND PRIMARY CONCERNS...HOWEVER SUFFICIENT MSTR FOR LOWER LCL/S AND PRESENCE OF BOUNDARY ALSO INDICATIVE OF POTENTIAL FOR FEW TORNADOES. RUC/NAM INDICATE THAT TSTMS MAY INITIALLY FORM NEAR THE MTNS/ADJACENT PLAINS 20-22Z PER LIFT FROM SHRTWV TROF/UPSLOPE FLOW/SFC HEATING WITH MCS EVENTUALLY EVOLVING AND ROLLING SE THRU PB. 06Z GFS HAS FARTHER E SOLN THAN NAM. SCT POPS ALREADY ACCOUNT FOR TSTMS N-NE THIS EVENING AND WILL OPT TO INCREASE POPS FAR W-SW. && .MAF WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ tx AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE SPOKANE WA 912 PM PDT SUN JUN 3 2007 .SYNOPSIS...A COLD FRONT WILL SURGE THROUGH THE INLAND NORTHWEST TONIGHT BRINGING AN END TO THE RECENT HOT WEATHER. BEHIND THE FRONT...TEMPERATURES WILL BE 10 TO 15 DEGREES COOLER ON MONDAY...AND EVEN COOLER TUESDAY AND WEDNESDAY. && .DISCUSSION... THE THREAT FOR SHOWERS AND THUNDERSTORMS HAS GREATLY DIMINISHED OVER THE PANHANDLE MOUNTAINS WITH THE LOSS OF SURFACE HEATING... BUT CONVECTION CONTINUES TO REGENERATE OVER WESTERN PORTIONS OF WASHINGTON TO AS FAR EAST AS YAKIMA. RUC ANALYSIS OF 500MB WINDS AND HEIGHTS SUGGESTS THAT SHOWERS AND THUNDERSTORMS DEVELOPING IN NORTHERN OREGON INTO WESTERN WASHINGTON ARE IN AN AREA OF UPPER LEVEL DIFFLUENCE. THERE IS SUFFICIENT ELEVATED CAPE TO SUSTAIN THUNDERSTORMS FOR PARCELS LIFTED FROM THE 800MB-700MB LAYER. SYNOPTIC SCALE FORCING APPEARS TO BE VERY WEAK SINCE THE UPPER TROUGH IS NOT EXPECTED TO MOVE EAST MUCH OVERNIGHT. Q-VECTOR CONVERGENCE REMAINS OFF SHORE THROUGH THE NIGHT...SO IT IS NOT LIKELY THAT SHOWERS WILL BE ABLE TO DEVELOP MUCH FURTHER EAST THAN THEY ARE AS OF 9 PM. USING THAT REASONING...SLIGHT CHANCES OF PRECIPITATION HAVE BEEN LIMITED TO MOSES LAKE...WATERVILLE...OMAK AND POINTS WEST. /GKOCH && .AVIATION... THE UPPER LEVEL RIDGE THAT HAS BEEN THE PREDOMINANT WEATHER FEATURE OVER THE INLAND NORTHWEST THE LAST SEVERAL DAYS WILL BE SHUNTED EAST TONIGHT AND TOMORROW. HIGH BASED MOUNTAIN...MAINLY MOUNTAIN THUNDERSTORMS ARE EXPECTED THIS EVENING OVER THE BLUE MOUNTAINS AND HIGH TERRAIN OF THE IDAHO PANHANDLE...AND SHOULD DISSIPATE BETWEEN 03-05Z. FURTHER WEST...ALONG THE CASCADES THE CLOSER PROXIMITY TO THE ADVANCING UPPER TROUGH SHOWERS AND THUNDERSTORMS HAVE A BETTER CHANCE OF REMAINING INTACT THROUGH TOMORROW MORNING...BUT CLOUD BASES WILL REMAIN AT OR ABOVE 1000 FEET GIVEN THE HOT AND DRY AIRMASS IN THE LOW LEVELS. /GKOCH && .PRELIMINARY POINT TEMPS/POPS... SPOKANE 62 82 54 68 46 65 / 10 20 60 50 20 20 COEUR D`ALENE 58 81 54 67 45 63 / 10 20 60 50 30 20 PULLMAN 57 81 52 66 45 61 / 10 20 60 50 20 30 LEWISTON 66 87 58 73 50 68 / 20 20 50 50 20 20 COLVILLE 58 84 54 69 42 66 / 10 20 60 50 40 40 SANDPOINT 56 82 52 69 44 60 / 10 30 50 50 40 40 KELLOGG 57 80 52 65 44 57 / 10 30 50 50 40 30 MOSES LAKE 66 87 55 73 48 70 / 10 20 60 40 20 20 WENATCHEE 69 82 54 71 52 68 / 20 20 60 50 10 20 OMAK 63 84 54 73 45 70 / 10 20 60 40 20 20 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...NONE. WA...NONE. && $$ wa AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 1106 AM CDT SUN JUN 3 2007 UPDATE... 12Z UPPER AIR ANALYSIS INDICATED A STACKED UPPER LOW CENTERED OVER FAR SWRN WI AT 15Z WITH SOME COLDER AIR ALOFT /500MB TEMPS OF -15C AT KDVN AND -16C AT KMPX/ TRYING TO FILTER INTO THE AREA. SFC TDS IN THE LOW-MID 60S STILL RESULTING IN MLCAPE VALUES OF 500-1000 J/KG THIS AFTERNOON...HOWEVER RELATIVELY COOL 700MB TEMPS COMBINED WITH MOIST ADIABATIC PROFILE STILL ONLY PRODUCING H7-H5 LAPSE RATES OF 5.5-6.0C PER KM. WITH DEEP LAYER SHEAR FAIRLY WEAK NOT EXPECTING MUCH OF A HAIL OR WIND THREAT TODAY...ALTHOUGH RUC MODEL DOES INDICATE POTENTIAL FOR DECENT VALUES OF 0-3KM CAPE AND SFC VORTICITY OVER THE ERN SECTIONS TODAY...WITH POTENTIAL ENHANCEMENT POSSIBLE ALONG LAKE BREEZE BOUNDARY. ENHANCED STRECTHING POTENTIAL (ESP) VALUES QUITE HIGH...SO AN ISOLATED WEAK TORNADO/COLD AIR FUNNEL IS POSSIBLE THIS AFTERNOON. OTHER CONCERN IS THREAT FOR HEAVY RAINFALL. CURRENT RADAR MOSAIC SHOWING A CLUSTER OF TSTMS OVER FAR WRN SECTIONS OF CWA WITH BROKEN LINE OF STORMS DEVELOPING SWD INTO NRN IL. RAINFALL EFFICIENCY WILL BE HIGH WITH THE STORMS DUE TO WARM RAIN PROCESSES...THUS INCLUDED HEAVY RAIN WORDING IN WRN AND NRN SECTIONS OF CWA. WILL HOLD OFF ON FLASH FLOOD WATCH FOR NOW BUT WILL CONTINUE TO MONITOR. && .PREV DISCUSSION... /ISSUED 304 AM CDT SUN JUN 3 2007/ DISCUSSION...FORECAST FOCUS IS ON RAIN CHANCES TODAY THROUGH TUESDAY. THE REMAINS OF A TROPICAL STORM MOVING UP THE EAST COAST HAVE SLOWED THE PROGRESSION OF THE UPPER LOW...AND ALSO THE MOVEMENT OF THE SURFACE SYSTEM. THE STACKED SYSTEM NOW SHOULD ROTATE OVER THE WESTERN GREAT LAKES REGION THROUGH MONDAY. WILL TREND TOWARD THE SLOWER GFS SOLUTION. SCATTERED SHOWERS ARE HAPPENING AT THIS TIME EVEN WITH THE UPPER SYSTEM STILL WEST OF THE CWA. I EXPECT DAYTIME HEATING ON THE UNSTABLE AIRMASS TO PRODUCE MORE WIDESPREAD CONVECTION...ESPECIALLY THIS AFTERNOON AND TONIGHT AS THE UPPER SYSTEM DRIFTS ACROSS SOUTHERN WISCONSIN. I WILL STAY CLOSE TO MAV MOS POPS TODAY AND TONIGHT. THE SYSTEM MOVES FURTHER EAST OF WISCONSIN MONDAY. HOWEVER...WISCONSIN REMAINS UNDER CYCLONIC CIRCULATION WITH COOL UNSTABLE AIR ALOFT. A SERIES OF SHORT WAVES ARE PREDICTED TO BE TRACKING ACROSS THE CWA IN THE NORTHWEST FLOW. THE COLUMN IS EXPECTED TO REMAIN SATURATED AND LAPS RATES WILL BE FAIRLY STEEP. I WILL STAY CLOSE TO MAV POPS AGAIN MONDAY AND MONDAY NIGHT. INSTABILITY PERSISTS THROUGH TUESDAY. A LF QUAD OF A 100KT H300 JET IS EXPECTED...AS WELL AS AROUND -20 AT H500. GFS PREDICTS SOME OMEGA AND ANOTHER SHORT WAVE. CONDITIONS WILL BE CLOSE TO THE -20 ALOFT AND 50 DEGREE SURFACE DEW POINT RULE. I WILL KEEP A CHANCE FOR THUNDERSTORMS IN THE FORECAST FOR TUESDAY. AVIATION...IFR VSBYS NORTH OF MKE ALONG/EAST OF LK BNDRY WL DISSIPATE AFTER SUNRISE. UPR LOW OVR SRN MN WL DRIFT OVR SRN WI THIS AFTERNOON. SCT INSTABILITY SHOWERS/THUNDERSTORMS WILL BECOME MORE NUMEROUS AS COLD POOL ALOFT SPREADS OVER RGN AT PEAK HEATING. WHILE MAINLY BKN VFR/MVFR CIGS AND VSBYS EXPECTED...LOCAL IFR CONDITIONS WITH HEAVIER SHOWERS AND STORMS. MKX WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR WIZ052-060. $$ && .MKX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99 wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LA CROSSE WI 303 PM CDT SAT JUN 2 2007 .SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT FORECAST CONCERN IS ON SEVERE WEATHER POTENTIAL THIS EVENING...THEN PRECIPITATION CHANCES THROUGH THE PERIOD WITH THE EVOLUTION OF THE SLOW MOVING UPPER LOW. 18Z SURFACE ANALYSIS SHOWS LOW PRESSURE LOCATED OVER SOUTHWEST MINNESOTA...WITH WEAK FRONTAL BOUNDARY EXTENDING OVER CENTRAL MINNESOTA AND THEN BACK SOUTH INTO EASTERN IOWA. VISIBLE SATELLITE IMAGERY SHOWS CUMULUS IN THE DRY SLOT FROM CENTRAL IOWA INTO CENTRAL MINNESOTA. RADAR MOSAIC SHOWS THUNDERSTORMS DEVELOPING FROM NORTH CENTRAL IOWA...INTO CENTRAL MINNESOTA IN AREA OF STRONGER INSTABILITY. THE RUC ANALYZES A POCKET OF STRONGER INSTABILITY OVER SOUTHEAST MINNESOTA AND NORTHERN IOWA WITH SURFACE BASED CAPE VALUES FROM 1000 TO 1500 J/KG. MEANWHILE SHORTWAVE ROTATING THROUGH NORTHWEST IOWA ASSISTING IN THE VERTICAL MOTION FIELDS IN VICINITY OF DEVELOPING CONVECTION. 12Z MODELS ARE IN GOOD AGREEMENT WITH THE OVERALL PATTERN THROUGH THE FORECAST PERIOD. VERTICALLY STACKED UPPER LOW OVER MINNESOTA WILL SLOWLY MOVE EASTWARD TO NEAR LA CROSSE BY 12Z SUNDAY AND INTO EASTERN WISCONSIN BY 00Z MONDAY. IN THE NEAR TERM...EXPECT CONVECTION TO CONTINUE TO DEVELOP AHEAD OF THE UPPER LOW THIS AFTERNOON AND THEN DECREASE LATER THIS EVENING AS INSTABILITY WANES. SEVERE THREAT LOOKS TO BE MAINLY LARGE HAIL AND WIND...ALTHOUGH ISOLATED TORNADOES MAY BE POSSIBLE EARLY THIS EVENING. (SEE HAZARDOUS WEATHER OUTLOOK FOR THE DETAILS). WILL HAVE HIGHER POPS THIS EVENING...THEN TAPER OFF LATER TONIGHT AS INSTABILITY WANES. WITH SYSTEM MOVING ACROSS THE FORECAST AREA SUNDAY AND GIVEN WHATS HAPPENING TODAY UNDER THE LOW ACROSS MINNESOTA WILL CONTINUE THE HIGHER POPS. INSTABILITIES WITH THE CLOUDS WILL BE RATHER LOW AND THUS NOT EXPECTING ANY TYPE OF SEVERE WEATHER...AS SYSTEM WILL BE OFF TO OUR EAST DURING THE PEAK HEATING OF THE AFTERNOON. WRAP AROUND MOISTURE WILL CONTINUE BEHIND LOW AS IT MOVES EASTWARD AND WEAKENS SUNDAY NIGHT AND MONDAY WITH WEAK IMPULSES ROTATING AROUND THE MAIN SYSTEM AND THUS WILL TAPER POPS OFF SUNDAY NIGHT WITH LOWER END POPS FOR MONDAY. WEAK HIGH PRESSURE NOSES INTO THE AREA ON TUESDAY WITH ITS MAIN EFFECTS BEING FELT ACROSS THE WESTERN ZONES. RESIDUAL MOISTURE ACROSS THE FAR EAST MAY RESULT IN A FEW SHOWERS AND THUS HAVE KEPT THE LOWER POPS IN FOR THOSE AREAS. LATER FORECASTS WILL HAVE TO MONITOR TO POSSIBLY REMOVE THEM IF HIGH BUILDS FARTHER EAST. TEMPERATURES WILL BE ON THE COOLER SIDE OVER THE NEXT SEVERAL DAYS. HAVE UNDERCUT GUIDANCE VALUES FOR HIGHS SUNDAY GIVEN AMOUNT OF CLOUDS AND SHOWERS EXPECTED. OTHERWISE AND COOL AND WET PERIOD EXPECTED THROUGH MICH OF THIS FORECAST TIME FRAME. .LONG TERM...WEDNESDAY THROUGH SATURDAY MEDIUM RANGE MODELS COMING INTO BETTER AGREEMENT FOR THE PERIOD. SOME MINOR TIMING DIFFERENCES STILL OCCURRING WITHIN THE FAST FLOW THAT WILL DOMINATE THE PERIOD. BOTH THE 00Z ECMWF AND 06Z GFS SHOW A RATHER POTENT SHORTWAVE ROTATING OUT OF THE NORTHERN ROCKIES INTO THE NORTHERN PLAINS AT THE BEGINNING OF THE PERIOD. STRENGTHENING SURFACE LOW MOVES OUT INTO THE NORTHERN PLAINS ON THURSDAY WITH WARM FRONT EXTENDING INTO THE GREAT LAKES REGION AND TRAILING COLD FRONT INTO THE CENTRAL AND SOUTHERN PLAINS. WARM ADVECTION AHEAD OF APPROACHING SYSTEM WILL RESULT IN PRECIPITATION CHANCES FROM WEDNESDAY AFTERNOON INTO FRIDAY AS ENTIRE SYSTEM PUSHES EASTWARD. LOOKS AS THOUGH SYSTEM WILL PUSH THROUGH LATER FRIDAY AND INTO SATURDAY WITH FRONTAL BOUNDARY LAYING UP TO THE SOUTH OF THE AREA. MINOR DIFFERENCES WITH FRONTAL POSITIONS AND TIMING WILL BE HARD TO ADD ANY SPECIFICITY TO FORECAST GRIDS. GIVEN STRENGTH OF SYSTEM AND MODEL PROGGED WIND PROFILES COULD SEE SOME SEVERE WEATHER WITH THIS SYSTEM AND THIS IN LINE WITH SPC`S DAYS 4-8 SEVERE WEATHER OUTLOOK. RABERDING && .AVIATION... SCATTERED TO NUMEROUS CONVECTION IS EXPECTED THROUGH 00Z SUNDAY ACROSS SOUTHEAST MINNESOTA AND NORTHEAST IOWA...AND THROUGH 02Z SUNDAY ACROSS WESTERN WISCONSIN. AS THE UPPER LEVEL LOW MOVES SLOWLY EAST ACROSS THE UPPER MISSISSIPPI RIVER VALLEY TONIGHT...CEILINGS WILL LIKELY LOWER INTO THE 1500 TO 3000 FOOT RANGE. THIS WILL LIKELY OCCUR BETWEEN 06Z AND 12Z SUNDAY. THESE LOW CEILINGS WILL LIKELY LINGER THROUGH THE DAY SUNDAY. && BOYNE .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 239 AM CDT SAT JUN 2 2007 .DISCUSSION...FORECAST FOCUS IS ON RAIN CHANCES TODAY THROUGH MONDAY. MODEL QPF PATTERNS ARE IN VERY GOOD AGREEMENT TODAY...AND ARE IN LINE WITH MOS POPS. RADAR AND SATELLITE LOOPS INDICATE ORGANIZED CONVECTION IN MISSOURI HEADING NORTHEAST...AND SHOULD ENTER SOUTHERN WISCONSIN BY 14Z. THIS IS IN STRONG AGREEMENT WITH MODEL AND HPC QPF PATTERNS. WATER VAPOR LOOPS AND CURRENT RUC INDICATE A SERIES OF SHORT WAVES DRIVING THE CONVECTION. LAPS RATES THIS AFTERNOON BECOME STEEP INTO THE EVENING HOURS...WHILE CAPES INCREASE TO NEAR 1000. THE ENTIRE STATE IS IN DAY ONE SLIGHT RISK. WILL STAY CLOSE TO MOS POPS AND TEMPERATURES TODAY AND TONIGHT. THE UPPER SYSTEM DRIFTS INTO WISCONSIN SUNDAY WITH THE CORE OF THE COLDEST AIR ALOFT. A STRONG SHORT WAVE AND SURFACE TROUGH ARE FORECAST. LAPS RATES WILL BE FAIRLY STEEP. HPC AND GFS QPF PATTERN ARE SIMILAR...AND IN LINE WITH HIGH MAV POPS. WILL AGAIN STAY CLOSE TO HIGH MAV POPS FOR SUNDAY. ALTHOUGH THE SYSTEM MOVES EAST OF WISCONSIN SUNDAY NIGHT AND MONDAY...THE COLDEST AIR ALOFT...-20...FILTERS INTO WISCONSIN. IN ADDITION...MODELS INDICATE A CONTINUING SERIES OF SHORT WAVES TRACKING ACROSS THE REGION IN THE NORTHWEST FLOW. WB ZERO HEIGHT LOWERS TO AROUND 8K FEET. SCATTERED SHOWERS ARE LIKELY MONDAY...AND EVEN AN ISOLATED THUNDERSTORMS IS POSSIBLE. && .AVIATION...EXCEPT FOR MVFR AND SOME LCL IFR VSBYS AND CIGS ALONG LK MICHIGAN...BNDRY LAYER WINDS SHOULD BE SUFFICIENT FOR MAINLY VFR CONDITIONS TO HOLD INTO THE EARLY MORNING HOURS. SHRT WAVE TROF BRINGS NEXT ROUND OF SHOWERS AND THUNDERSTORMS WITH MVFR CIGS AND VSBYS INTO SWRN WI AROUND/AFT 13Z. ERN WI SHOULD REMAIN RAIN FREE UNTIL 17-18Z. && .MKX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 35/09 wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 200 AM MDT MON JUN 4 2007 .DISCUSSION...FORECAST CONCERNS ARE MANY TODAY AND INCLUDE PRECIPITATION CHANCES TODAY/TONIGHT AND AGAIN TUESDAY/TUESDAY NIGHT. SMALL MCS FORMATION POSSIBLE ACROSS THE EAST TUESDAY NIGHT. FOR WEDNESDAY THEY INCLUDE TEMPERATURES WITH 100 DEGREES POSSIBLE...STRONG WEST TO SOUTHWEST WINDS POSSIBLY REACHING ADVISORY CRITERIA AND SLIM CHANCES FOR THUNDERSTORMS. ON TOP OF ALL THIS WE WILL ALSO NEED TO DEAL WITH STRATUS AND/OR FOG FORMATION TONIGHT AND AGAIN TUESDAY NIGHT FOR PARTS OF THE AREA. .SHORT TERM (TODAY-WEDNESDAY NIGHT)... TODAY/TONIGHT...LATEST 700-500 RH AND 250 DIVERGENCE FORECASTS FROM THE MODELS SHOW ANOTHER ORGANIZED WEATHER FEATURE ALOFT AS WELL AS A COLD FRONT TO MOVE TOWARD THE NEBRASKA/KANSAS BORDER LATE IN THE DAY. ANOTHER FEATURE MOVES DOWN THE FRONT RANGE WARRANTING SLIGHT CHANCE POPS ACROSS PARTS OF FAR EASTERN COLORADO. THESE FEATURES CONTINUE SOUTH DURING THE NIGHT. WILL ADD SLIGHT CHANCE POPS THROUGH MIDNIGHT WITH THE EXPECTATION THAT THE ACTIVITY WILL BE OUT OF THE AREA SHORTLY THEREAFTER. BEHIND THE FRONTAL BOUNDARY LOW LEVEL MOISTURE INCREASES QUITE A BIT WITH THE GFS/NAM/RUC SHOWING STRATUS FORMATION. HOW FAR SOUTHWEST THE FRONT GETS WILL DETERMINE HOW MUCH OF THE AREA GETS THE LOW CLOUDINESS. FOR NOW HAVE GONE WITH THE RUC/GFS WHICH CLIP THE NORTHEAST CORNER OF OUR AREA AFTER 06Z. IF CONVECTION REALLY GETS GOING THE FRONT MAY BE INDEED FURTHER SOUTHWEST LIKE THE NAM INDICATES AND THE STRATUS WILL NEED TO BE BROUGHT FURTHER SOUTHWEST. GOOD AGREEMENT BETWEEN 850 AND 2M/MOS GUIDANCE NUMBERS WITH EXPECTED HIGH TEMPERATURES IN THE 80-84 DEGREE RANGE ACROSS THE AREA. TUESDAY/TUESDAY NIGHT...MODELS SHOW SOME GOOD AGREEMENT WITH ANOTHER ORGANIZED UPPER DISTURBANCE AND ASSOCIATED 850-500 MOISTURE POCKET MOVING THROUGH THE AREA DURING THE AFTERNOON HOURS. THIS FEATURE SHOULD JUST ABOUT BE OUT OF THE AREA BY 00Z SO ANY POPS THEREAFTER WOULD BE MINIMAL. HIGHEST SLIGHT CHANCE POPS (24%) WILL BE OVER THE NORTHEAST TAPERING TO 15% ACROSS THE SOUTHWEST 1/3 OF THE AREA. THIS GENERAL TREND CONTINUES THROUGH MIDNIGHT. MAY SEE A RETURN OF STRATUS AND DEPENDING ON THE FRONTS POSITION DICTATES HOW FAR SOUTHWEST IT REACHES. FOR NOW HAVE KEPT IT JUST NORTHEAST OF OUR AREA. TEMPERATURES WILL BE VERY TROUBLESOME AS EASTERLY THEN SOUTHEASTERLY WINDS DEVELOP DURING THE DAY. THIS IS UNFAVORABLE FOR STRONG WARMING. 850 TEMPERATURES FROM THE GFS/NAM/NGM/UKMET AND 2M/MOS GUIDANCE NUMBERS ARENT ALL THAT FAR APART WITH READINGS NEAR 80 ACROSS THE NORTHEAST TO MID 80S ACROSS THE FAR SOUTHWEST AND WEST. WEDNESDAY/WEDNESDAY NIGHT...VERY ACTIVE WEATHER DAY. LARGE UPPER TROUGH WITH PRIMARY LOW AND SURFACE LOW ACROSS NORTHERN WYOMING WILL SWEEP ACROSS THE AREA DURING THE DAY. BREEZY TO WINDY SOUTHWEST WINDS WILL BECOME WESTERLY ACROSS MUCH OF THE WESTERN 1/2 OF THE AREA WITH SPEEDS PUSHING ADVISORY CRITERIA. MOISTURE BELOW 700MB IS VERY DRY THANKS TO THE WESTERLY WINDS. MOISTURE IN THE 700-300 IS A BIT BETTER BUT WOULD FAVOR RATHER HIGH BASED STORMS. GFS INSTABILITY IS WEAK...PROBABLY DUE TO THE LACK OF LOW LEVEL MOISTURE. LOOKING AT 850 THETA-E CONVERGENCE ALONG THE FRONT/DRYLINE AS A GUIDE WOULD SUGGEST SOME SLIGHT CHANCE POPS ACROSS THE EASTERN 1/3 OF THE AREA. SURROUNDING OFFICES HAVE THIS IDEA GOING SO WILL ADJUST ACCORDINGLY. ANY PRECIP THAT MANAGES TO DEVELOP WILL QUICKLY BE OUT OF THE AREA AFTER 00Z SO HAVE REMOVED POPS. 850 TEMPERATURES FROM THE GFS/NAM/UKMET ALL SUPPORT HIGHS IN THE MID 90S ACROSS THE WEST TO NEAR 105 ACROSS THE HILL CITY AREA. GIVEN THE DRY WEST WIND AT 850MB ITS CERTAINLY POSSIBLY 2M/MOS GUIDANCE NUMBERS AT LEAST 10F COOLER. FOR NOW HAVE GONE WITH NEAR 90 ACROSS THE FAR WEST TO 100 AT HILL CITY AND 102 IN THE GOVE COUNTY AREA...STAYING WITH COLLABORATIVE GUIDELINES. THESE MAY BE A BIT UNDERDONE...WE STILL HAVE ANOTHER DAY TO TWEAK THEM. .LONG TERM (THURSDAY-SUNDAY)... THURSDAY...TEMPERATURES WILL DROP ABOUT 15 TO 20 DEGREES FROM WEDNESDAYS READINGS WITH EXPECTED HIGHS IN THE LOW TO MID 80S. NO INSTABILITY TO SPEAK OF AND NEARLY ZONAL FLOW NOT REAL FAVORABLE FOR THUNDERSTORM DEVELOPMENT. AS A RESULT HAVE DROPPED PREVIOUS FORECAST OF SLIGHT CHANCE OF THUNDERSTORMS. FRIDAY...GOOD AGREEMENT BETWEEN THE GFS/ECMWF/DGEX IN FURTHER DROPPING AFTERNOON TEMPERATURES PER 850 TEMPERATURES. CONSENSUS AMONGST THE 3 WOULD SUGGEST HIGHS AROUND 70 IN THE NORTH TO THE MID 70S ACROSS THE SOUTH...AT LEAST 5F COOLER THEN CURRENTLY ADVERTISED. WILL DROP THEM FURTHER WHILE STAYING WITHIN COLLABORATIVE GUIDELINES. AN UPPER DISTURBANCE EJECTS WITH WHAT ONCE WAS AN UPPER LOW WITHIN THE SOUTHWEST FLOW ALOFT. THIS DISTURBANCE IS EXPECTED TO MOVE INTO FAR EASTERN COLORADO BY THE END OF THE DAY...FAVORING SLIGHT CHANCE POPS ACROSS THE WEST. AS A RESULT HAVE REMOVED THEM ACROSS THE EAST. SATURDAY-SUNDAY...NO CHANGES MADE. 850 TEMPERATURES START TO WARM AGAIN DESPITE WEAK TROUGHING AT 500MB. && .AVIATION... VFR CONDITIONS WITH JUST A FEW CLOUDS FOR MUCH OF THE DAY. UPPER DISTURBANCE SHOULD MOVE INTO THE KMCK AREA AROUND 22Z-00Z AND THE KGLD AREA AROUND OR SHORTLY AFTER 03Z WITH TSRA POSSIBLE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ DDT/DDT/DDT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 1050 AM CDT MON JUN 4 2007 .DISCUSSION... ONLY REAL CHANGES TO MORNING UPDATE INVOLVE TEMPS. RAISED HIGHS SEVERAL DEGREES BASED ON 15Z OBS AND SUGGESTIONS FROM FORECAST SOUNDINGS. PCPN TRENDS SEEM RIGHT ON TRACK PER EXTRAPOLATION OF CURRENT WX...REACHING FAR NWRN FCST AREA BY 19Z. CONVECTION... ELEVATED FOR THE TIME BEING...ACROSS SD/MN AHEAD OF NRN PLAINS SHRT WV WILL LIKELY EXPAND IN COVERAGE AND INTENSITY AS IT CONTINUES TO DROP SWD. TSTMS SHOULD BECOME MORE SFC BASED WITH TIME AS MLCAPE INCREASES AND CIN ERODES PER 12Z RUC/NAM. MAY SEE A FEW SVR TSTMS BUT LACK OF SHEAR SHOULD LIMIT THAT THREAT. && .PREV DISCUSSION... SUBJECTIVE SFC ANALYSIS AT 03Z SHOWS OLD LOW NEAR KMKG IN LOWER MICHIGAN. WEAK TROUGHS OF LOW PRESSURE CONTINUE TO ROTATE AROUND THE LOW WITH ONE IN SOUTHERN MO AND ANOTHER TROUGH OVER NORTHERN IA. A THIRD IS LINING UP OVER NORTH DAKOTA THROUGH NORTHERN MN TNT. ALOFT...LOW OVER THE MIDWEST HAS PHASED WITH THE REMNANTS OF TD BERRY ALONG THE EAST COAST FORMING ONE LARGE ELONGATED TROUGH FROM H850 TO H700. H500 CONTINUES TO SHOW APPROACHING WAVE NEAR LAKE WINNIPEG THAT IS EXPECTED TO IMPACT THE REGION THIS AFTERNOON AND EVENING. HT FALLS AHEAD OF THE UPPER LVL SYSTEM OVER WI ARE QUITE MEAGER AND LOW ON THE EAST COAST SHOULD SLOW THINGS DOWN A BIT...SO NOT EXPECTING MUCH EASTWARD PROGRESSION OF LOW TODAY. GFS SEEMS TO HAVE A BETTER HANDLE ON THE EXITING UPPER LOW WITH TONIGHT 00Z RUN. ATTENTION IN THE SHORT TERM CONTINUES TO FOCUS ON NEXT UPSTREAM WAVE OVER SOUTHERN CANADA NOW ENTERING EXTREME NORTHERN ND. WATER VAPOR IMAGERY SHOWS LIGHTNING FOOTPRINT ENTERING THE CONUS WITH DECENT MID LEVEL JET MAX OF 40KTS FORCING THE SYSTEM SOUTHEAST WITH TIME. BOTH NAM AND GFS NOW BACKING OFF ON TIMING OF WIND MAX REACHING THE AREA WITH 40 TO 50 KTS AFTER 06Z TUES. NONE THE LESS...GFS STILL PAINTS A 400-600 J/KG STRIPE WITH MAX VALUES APPROACHING 1000 J/KG OVER CENTRAL NE BY 00Z TUES. NAM NOT QUITE AS STRONG WITH INSTABILITY. WAVE COMBINED WITH WEAK COLD FRONTAL FORCING AND CONVERGENCE SHOULD YIELD PERIOD OF SHOWERS AND THUNDERSTORMS FROM LATE AFTERNOON THROUGH EVENING. HIGH BUILDS IN FOR TUESDAY WITH LITTLE SENS WX. SEASONAL TO SLIGHTLY BELOW NORMAL READINGS EXPECTED AS H850 TEMPS FALL TO +8 TO +11C OVER THE FORECAST AREA. MAIN SYSTEM STILL PROGGED TO ARRIVE WED WITH LEADING THETAE ADVECTION LATE TUES. MODELS STILL ADVERTISING THE WARMING ALOFT ARRIVES NEARLY CONCURRENTLY WITH LLVL MOISTURE RESULTING IN MODERATE TO HIGHLY CAPPED ENVIRONMENT. NET RESULT IS CONDITIONAL THUNDER ALONG THE LEADING EDGE MOST LIKELY WITH SOME HINT AT DEVELOPMENT OVER SOUTHERN IA/N MO AS WARM FRONT PUSHES NORTH WEDNESDAY AFTERNOON. CAP QUICKLY TAKES OVER FOR THE LATE DAY HOURS AS BULK SHEAR INCREASES NORTHWEST. GFS/GEM SHOW DEEP LOW WITH STRONG DIFFLUENCE AND NEGATIVELY TILTED TROUGH OVER EASTERN SOUTH DAKOTA DURING THE EVENING. WITH BULK SHEAR OF 60 TO 90 KTS FROM NW IA TO EASTERN NE/SD...FEEL GREATEST THREAT OF SVR WILL BE NORTHWEST PORTION OF FORECAST AREA EARLY ON WED NIGHT WITH SIGNIFICANT OUTBREAK THERE...THEN CONTINUED SEVERE EXPANDING THROUGH CENTRAL SECTIONS WHEN MORE LINEAR CONVECTION PROPAGATES EASTWARD TOWARD MORNING WITH DURING OVERNIGHT HOURS. RESULTANT SEVERE OF WIND AND HAIL FOR MOST OF REGION THOUGH MAY ALSO BE DEALING WITH SOME TORNADO THREAT DURING THE NIGHT THROUGH CENTRAL SECTIONS BASED ON CURRENT PROGS. WIND FIELDS VERY IMPRESSIVE FROM H850-H700 WITH 60KTS PROGGED OVER KDSM AT 06Z. DETAILS TO COME INTO FOCUS NEXT SEVERAL DAYS AS TIMING AND PLACEMENT ISSUES BECOME MORE SOLIDIFIED. BEYOND MAIN FROPA...SECONDARY FRONT TO PASS THROUGH THE REGION THUR NIGHT /FRIDAY WITH COOL CANADIAN HIGH TO SETTLE INTO AREA. FRONT EXPECTED TO RETURN SAT AFTERNOON/EVENING BASED ON GEM. THUS MORE WET WEATHER AS MOISTURE POOL SOUTH ADVECTS NORTH INTO REGION SO UNSETTLED WEATHER EXPECTED TO CONTINUE. && .AVIATION...04/06Z ISOLD -SHRA POSSIBLE FROM KALO TO KOTM TIL 10Z. ALSO A CHANCE OF CIGS 015 AT THOSE SITES 08Z-13Z. OTHERWISE EXPECT VFR CONDS THROUGH THE TAF PERIOD. ONLY EXCEPTION IS AFT 18Z MON WHEN PROB30 FOR -TSRA ENTERS PICTURE NW TO SE THROUGH 03Z. COULD HAVE TEMPORARILY REDUCED VSBY AND LOWER CIGS. LEFT TS OUT OF KMCW TAF DUE TO MORE STABLE AIRMASS UP THERE. NWLY WINDS WILL PICK UP BY 15Z MOST LOCATIONS WITH GUSTS TO AT LEAST 25KT THROUGH MUCH OF DAY. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 945 AM MDT MON JUN 4 2007 .UPDATE...LATEST SURFACE ANALYSIS SHOWS COLD FRONT STILL IN CANADA...AND LATEST MODEL RUNS SHOW THE FRONT ARRIVING OVERNIGHT. HAVE THUS PULLED POPS FOR THE SOUTHERN 3 TIERS OF KANSAS COUNTIES...AS ANY CONVECTION ASSOCIATED WITH THE FRONT SHOULD NOT ARRIVE UNTIL AFTER 00Z IN THESE LOCATIONS. CLOUD COVER FORECAST WAS ALSO UPDATED TO REFLECT CURRENT CONDITIONS. && .PREV DISCUSSION... /ISSUED 200 AM MDT MON JUN 4 2007/ DISCUSSION...FORECAST CONCERNS ARE MANY TODAY AND INCLUDE PRECIPITATION CHANCES TODAY/TONIGHT AND AGAIN TUESDAY/TUESDAY NIGHT. SMALL MCS FORMATION POSSIBLE ACROSS THE EAST TUESDAY NIGHT. FOR WEDNESDAY THEY INCLUDE TEMPERATURES WITH 100 DEGREES POSSIBLE...STRONG WEST TO SOUTHWEST WINDS POSSIBLY REACHING ADVISORY CRITERIA AND SLIM CHANCES FOR THUNDERSTORMS. ON TOP OF ALL THIS WE WILL ALSO NEED TO DEAL WITH STRATUS AND/OR FOG FORMATION TONIGHT AND AGAIN TUESDAY NIGHT FOR PARTS OF THE AREA. SHORT TERM (TODAY-WEDNESDAY NIGHT)... TODAY/TONIGHT...LATEST 700-500 RH AND 250 DIVERGENCE FORECASTS FROM THE MODELS SHOW ANOTHER ORGANIZED WEATHER FEATURE ALOFT AS WELL AS A COLD FRONT TO MOVE TOWARD THE NEBRASKA/KANSAS BORDER LATE IN THE DAY. ANOTHER FEATURE MOVES DOWN THE FRONT RANGE WARRANTING SLIGHT CHANCE POPS ACROSS PARTS OF FAR EASTERN COLORADO. THESE FEATURES CONTINUE SOUTH DURING THE NIGHT. WILL ADD SLIGHT CHANCE POPS THROUGH MIDNIGHT WITH THE EXPECTATION THAT THE ACTIVITY WILL BE OUT OF THE AREA SHORTLY THEREAFTER. BEHIND THE FRONTAL BOUNDARY LOW LEVEL MOISTURE INCREASES QUITE A BIT WITH THE GFS/NAM/RUC SHOWING STRATUS FORMATION. HOW FAR SOUTHWEST THE FRONT GETS WILL DETERMINE HOW MUCH OF THE AREA GETS THE LOW CLOUDINESS. FOR NOW HAVE GONE WITH THE RUC/GFS WHICH CLIP THE NORTHEAST CORNER OF OUR AREA AFTER 06Z. IF CONVECTION REALLY GETS GOING THE FRONT MAY BE INDEED FURTHER SOUTHWEST LIKE THE NAM INDICATES AND THE STRATUS WILL NEED TO BE BROUGHT FURTHER SOUTHWEST. GOOD AGREEMENT BETWEEN 850 AND 2M/MOS GUIDANCE NUMBERS WITH EXPECTED HIGH TEMPERATURES IN THE 80-84 DEGREE RANGE ACROSS THE AREA. TUESDAY/TUESDAY NIGHT...MODELS SHOW SOME GOOD AGREEMENT WITH ANOTHER ORGANIZED UPPER DISTURBANCE AND ASSOCIATED 850-500 MOISTURE POCKET MOVING THROUGH THE AREA DURING THE AFTERNOON HOURS. THIS FEATURE SHOULD JUST ABOUT BE OUT OF THE AREA BY 00Z SO ANY POPS THEREAFTER WOULD BE MINIMAL. HIGHEST SLIGHT CHANCE POPS (24%) WILL BE OVER THE NORTHEAST TAPERING TO 15% ACROSS THE SOUTHWEST 1/3 OF THE AREA. THIS GENERAL TREND CONTINUES THROUGH MIDNIGHT. MAY SEE A RETURN OF STRATUS AND DEPENDING ON THE FRONTS POSITION DICTATES HOW FAR SOUTHWEST IT REACHES. FOR NOW HAVE KEPT IT JUST NORTHEAST OF OUR AREA. TEMPERATURES WILL BE VERY TROUBLESOME AS EASTERLY THEN SOUTHEASTERLY WINDS DEVELOP DURING THE DAY. THIS IS UNFAVORABLE FOR STRONG WARMING. 850 TEMPERATURES FROM THE GFS/NAM/NGM/UKMET AND 2M/MOS GUIDANCE NUMBERS ARENT ALL THAT FAR APART WITH READINGS NEAR 80 ACROSS THE NORTHEAST TO MID 80S ACROSS THE FAR SOUTHWEST AND WEST. WEDNESDAY/WEDNESDAY NIGHT...VERY ACTIVE WEATHER DAY. LARGE UPPER TROUGH WITH PRIMARY LOW AND SURFACE LOW ACROSS NORTHERN WYOMING WILL SWEEP ACROSS THE AREA DURING THE DAY. BREEZY TO WINDY SOUTHWEST WINDS WILL BECOME WESTERLY ACROSS MUCH OF THE WESTERN 1/2 OF THE AREA WITH SPEEDS PUSHING ADVISORY CRITERIA. MOISTURE BELOW 700MB IS VERY DRY THANKS TO THE WESTERLY WINDS. MOISTURE IN THE 700-300 IS A BIT BETTER BUT WOULD FAVOR RATHER HIGH BASED STORMS. GFS INSTABILITY IS WEAK...PROBABLY DUE TO THE LACK OF LOW LEVEL MOISTURE. LOOKING AT 850 THETA-E CONVERGENCE ALONG THE FRONT/DRYLINE AS A GUIDE WOULD SUGGEST SOME SLIGHT CHANCE POPS ACROSS THE EASTERN 1/3 OF THE AREA. SURROUNDING OFFICES HAVE THIS IDEA GOING SO WILL ADJUST ACCORDINGLY. ANY PRECIP THAT MANAGES TO DEVELOP WILL QUICKLY BE OUT OF THE AREA AFTER 00Z SO HAVE REMOVED POPS. 850 TEMPERATURES FROM THE GFS/NAM/UKMET ALL SUPPORT HIGHS IN THE MID 90S ACROSS THE WEST TO NEAR 105 ACROSS THE HILL CITY AREA. GIVEN THE DRY WEST WIND AT 850MB ITS CERTAINLY POSSIBLY 2M/MOS GUIDANCE NUMBERS AT LEAST 10F COOLER. FOR NOW HAVE GONE WITH NEAR 90 ACROSS THE FAR WEST TO 100 AT HILL CITY AND 102 IN THE GOVE COUNTY AREA...STAYING WITH COLLABORATIVE GUIDELINES. THESE MAY BE A BIT UNDERDONE...WE STILL HAVE ANOTHER DAY TO TWEAK THEM. LONG TERM (THURSDAY-SUNDAY)... THURSDAY...TEMPERATURES WILL DROP ABOUT 15 TO 20 DEGREES FROM WEDNESDAYS READINGS WITH EXPECTED HIGHS IN THE LOW TO MID 80S. NO INSTABILITY TO SPEAK OF AND NEARLY ZONAL FLOW NOT REAL FAVORABLE FOR THUNDERSTORM DEVELOPMENT. AS A RESULT HAVE DROPPED PREVIOUS FORECAST OF SLIGHT CHANCE OF THUNDERSTORMS. FRIDAY...GOOD AGREEMENT BETWEEN THE GFS/ECMWF/DGEX IN FURTHER DROPPING AFTERNOON TEMPERATURES PER 850 TEMPERATURES. CONSENSUS AMONGST THE 3 WOULD SUGGEST HIGHS AROUND 70 IN THE NORTH TO THE MID 70S ACROSS THE SOUTH...AT LEAST 5F COOLER THEN CURRENTLY ADVERTISED. WILL DROP THEM FURTHER WHILE STAYING WITHIN COLLABORATIVE GUIDELINES. AN UPPER DISTURBANCE EJECTS WITH WHAT ONCE WAS AN UPPER LOW WITHIN THE SOUTHWEST FLOW ALOFT. THIS DISTURBANCE IS EXPECTED TO MOVE INTO FAR EASTERN COLORADO BY THE END OF THE DAY...FAVORING SLIGHT CHANCE POPS ACROSS THE WEST. AS A RESULT HAVE REMOVED THEM ACROSS THE EAST. SATURDAY-SUNDAY...NO CHANGES MADE. 850 TEMPERATURES START TO WARM AGAIN DESPITE WEAK TROUGHING AT 500MB. AVIATION... VFR CONDITIONS WITH JUST A FEW CLOUDS FOR MUCH OF THE DAY. UPPER DISTURBANCE SHOULD MOVE INTO THE KMCK AREA AROUND 22Z-00Z AND THE KGLD AREA AROUND OR SHORTLY AFTER 03Z WITH TSRA POSSIBLE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ SFJ/DDT ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1150 AM EDT MON JUN 4 2007 .UPDATE... WV IMAGERY AND RUC ANALYSIS INDICATED THAT THE MID/UPPER LEVEL LOW WAS SLOWLY MOVING E THROUGH SRN LAKE MI. STRONG 700-500 MB FGEN ON ITS NW FLANK SUPPORTED THE PERSISTENT AREA OF RAIN ACRS SE UPPER MI. THE 12Z NAM AND RUC SUGGEST THAT THE SUPPORTING DYNAMICS SHOULD GRADUALLY WEAKEN AND SLIDE OFF TO THE EAST. SO...ADDITIONAL RAINFALL OF AROUND 0.25-0.50 INCH MAY BE POSSIBLE OVER THE SE THIRD OF UPPER MI THIS AFTERNOON WITH THE PCPN GRADUALLY TAPERING OFF AND ENDING. SOME LOCATIONS IN FAR RURAL PORTIONS OF SW DELTA COUNTY AND EASTERN MENOMINEE COUNTY HAD RECEIVED FROM 2.5 TO 4.0 INCHES OF RAIN SINCE YESTERDAY. EXPECT POTENTIAL FOR ADDITIONAL SCT -SHRA INTO WRN LAKE SUPERIOR AND W UPPER MI THIS AFTERNOON AS A SHRTWV NW OF CYQT MOVES TOWARD THE AREA. && .PREV DISCUSSION...ISSUED 442 AM EDT MON JUN 4 2007 ADDED A SLIGHT CHANCE FOR THUNDER THROUGH 18Z TODAY FOR THE EASTERN THIRD OF THE AREA...BUT WILL KEEP ONLY SHOWERS AFTERWORDS. LOOKING BACK AT WHAT OCCURRED YESTERDAY ACROSS WESTERN MINNESOTA...ON THE BACK SIDE OF THE 500MB LOW...THIS SEEMS REALISTIC. WITH PIECES OF ENERGY CONTINUING TO ROLL THROUGH AROUND THE LARGE SCALE TROUGH TONIGHT...WILL NOT BE OUT OF THE QUESTION TO GET A COUPLE OF LIGHTNING STRIKES...BUT AT THIS TIME IT DOES NOT SEEM LIKE A GOOD ENOUGH CHANCE TO MENTION IN THE ONGOING FORECAST BEYOND THIS MORNING. IN FACT...WITH THE JUST RECENTLY UPDATED DAY1 CONVECTIVE OUTLOOK...ONLY THE EASTERN MOST FRINGE IS INCLUDED IN THE GENERAL RISK AREA. AM GOING BACK AND FORTH WITH OUR DRY FORECAST FOR THE OVERNIGHT HOURS ACROSS THE WESTERN HALF TO THIRD OF THE CWA. BELIEVE THAT THE GFS HAS BEEN DOING A RELATIVELY GOOD JOB AND WAS INITIALIZED WELL...AND DO NOT REALLY WANT TO CUT OUT ITS LOW PRECIP AMOUNTS FOR THE OVERNIGHT PERIOD. UPSTREAM...THE SYSTEM THAT MAY BRING US LIGHT PRECIPITATION IS CURRENTLY CREATING TEMPERATURES OF 32 DEGREES OF -SHSN AT CYYQ IN NORTHERN MANITOBA. THIS DOES VALIDATE THE GFS A LITTLE MORE THAN THE NAM FORECAST FOR LATE TONIGHT. STILL...ANY PRECIPITATION THAT DOES FALL IF IT DOES SHOULD BE FAIRLY LIGHT...SO WILL BE OPTIMISTIC AND KEEP THE MENTION OF ANY PROLONGED SHOWER ACTIVITY OUT AFTER 03Z TUESDAY. THE 06Z NAM ACTUALLY LOOKS VERY SIMILAR TO OUR FORECAST THAT WE JUST ISSUED...SUPPORTING THE LACK OF CHANGE. WILL A FROST ADVISORY BE NEEDED FOR TUESDAY NIGHT INTO WEDNESDAY GIVEN THE COOL TEMPERATURES AND LIGHT WINDS? WELL...IF THE NAM IS CORRECT IT VERY WELL MAY BE. HOWEVER...THE GFS WOULD KEEP MORE CLOUDS OVER THE PRIME LOCATIONS INHIBITING MUCH IN THE WAY OF FROST DEVELOPMENT. HAVE INCREASED THE AREA FOR FOG...FOR ALL AREAS WHERE MIN TEMPS WILL BE AT OR LOWER THAN 36F. BUT ONCE AGAIN...IT WILL NEED TO BE REANALYZED BY LATER SHIFTS WITH A BETTER HANDLE ON THE WIND AND SKY COVER BY LATER MODEL RUNS. CUT BACK TEMPERATURES FOR WEDNESDAY NIGHT INTO THURSDAY MORNING BY A COUPLE OF DEGREES...ESPECIALLY ACROSS THE EASTERN HALF EVEN WITH A STRONG SOUTH TO SOUTHEASTERLY BREEZE. AS FOR WEATHER DURING THIS TIME PERIOD...HAVE MADE FEW IF ANY ADJUSTMENTS. && .MARINE...4 AM ISSUANCE PATCHY FOG WILL PERSIST OVER LAKE SUPERIOR THIS MORNING AND THEN DISSIPATE BY AFTERNOON AS STRONGER NORTH WINDS BRING IN DRIER AIR FROM ONTARIO. THE GRADIENT BEHIND LOW PRESSURE DEPARTING FROM LOWER MI WILL BE TIGHT ENOUGH TO PRODUCE N WINDS GENERALLY IN THE 15 TO 25 KT RANGE WITH THE STRONGEST WINDS OVER EASTERN LAKE SUPERIOR. COLDER AIR AND EFFECTIVE MIXING OF WINDS TO THE SFC SHOULD RESULT IN 4 TO 7 FT WAVES BY LATE MON. A RIDGE BUILDING IN WILL SLACKEN GRADIENT WINDS AND BRING WAVES BACK DOWN ON TUE. A STRONG LOW DEVELOPING OVER THE NORTHERN ROCKIES BY MIDWEEK WILL MOVE TOWARD THE UPPER MISSISSIPPI VALLEY ON THU. TIGHTENING GRADIENT AHEAD OF THE APPROACHING LOW WILL RESULT IN WINDS TO AROUND 30 KT WHILE WAVES BUILD TO THE 6 TO 10 FT RANGE. SW WINDS VEERING W WILL APPROACH GALE STRENGTH THU NIGHT INTO FRI AS THE LOW AND FRONT DEPART TO THE NORTHEAST. && .AVIATION...FOR 12Z TAF ISSUANCE SCT SHRA WILL CONTINUE NORTH OF THE MID/UPPER LEVEL LOW AND AFFECT MAINLY KSAW THROUGH 18Z. VLIFR TO LIFR CIGS WILL CONTINUE TO BE A PROBLEM AT KSAW THROUGH THE MORNING HOURS WITH UPSLOPE/ONSHORE NRLY FLOW OFF LAKE SUPERIOR. AT SAME TIME...INCREASING MIXING WITH STRONGER NRLY FLOW AND SCT SHRA MAY WORK TO OCCASIONALLY IMPROVE VSBYS ABV IFR AT KSAW THIS MORNING. LOOK FOR INCREASINGLY DRIER AIR TO ERODE STRATUS DECK AT KSAW BY 21Z AS VFR CONDITIONS PREVAIL THEREAFTER. ADVECTION OF DRIER AIR UPSTREAM OF WESTERN LAKE SUPERIOR AND DOWNSLOPING NRLY WIND SHOULD WORK TO KEEP VSBYS VFR AT KCMX. MVFR STRATUS CLOUDS WILL LINGER ON THE BACKSIDE OF LOW UNTIL LATE MORNING AT WHICH TIME DRY AIR ADVECTION SHOULD SCATTER OUT LOWER DECK. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...JLB PREV DISCUSSION...KF AVIATION/MARINE...JV mi AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 1025 AM CDT MON JUN 4 2007 .DISCUSSION... GOING FORECAST PRETTY MUCH ON TRACK FOR PRECIP TIMING THIS MORNING. HIGH BASED SHOWERS DRIFTING SOUTH BETWEEN WEAK BACKDOOR COLD FRONT OVER CENTRAL CWA AND SHORTWAVE DROPPING SOUTH THROUGH THE RED RIVER VALLEY. GENERALLY LOOKING AT HIGH BASED SHOWERS INITIALLY...BUT MAY SEE SOME STORMS BECOME SURFACE BASED ACROSS THE SOUTHERN CWA THIS AFTERNOON AS SURFACE HEATS OUT. 12Z NAM/RUC SHOWING BEST INSTABILITY ACROSS THE SOUTHWEST 1/4 OF THE CWA...AND COULD SEE SOME PULSE TSRA PRODUCE SMALL HAIL...MARGINALLY SEVERE AT BEST. EARLIER HWO WORDING FOR THIS LOOKS OK...THOUGH MAY TRY TO DEFINE THE AREA OF THE BETTER POTENTIAL FOR STRONG STORMS A BIT BETTER. && .AVIATION... NOT TOO MANY AVIATION PRBLMS EXPECTED NEXT 24 HRS. ISOLATED TSRA EMBEDDED IN GREATER COVERAGE OF HIGH BASED SHRA SPREADING SOUTH OVER THE AREA THIS MORNING. TSRA MAY INCREASE IN COVERAGE DURING THE AFTERNOON...ESPECIALLY ALONG/SOUTH OF I-90. SHOULD SEE GENERALLY VFR CIGS/VSBYS THRU PD...THOUGH LOCALLY MVFR VSBYS IN HEAVIER TSRA POSSIBLE BETWEEN 18Z-00Z AROUND KFSD/KSUX. && .PREV DISCUSSION... RATHER DYNAMIC AND BUSY PATTERN WILL CONTINUE UFN. SCT SHRA/TSRA ALREADY OCCURRING WITH CDFNT AND ASSCD SHORT WAVE INTO ND ATTM... WHICH WILL MOVE SSEWD OVR CWA THIS AFTN. PREV FCST RATHER WELL TIMED...BUT BEEFED UP POPS JUST SHORT OF LIKELY ESP EARLY AFTN IN SD PTN OF CWA. AGAIN GOOD LAPSE RATES IN LOW TO MID LVLS WITH SOME HAIL EXPCD...BUT THINK IT WILL BE SHORT OF ANY SVR DUE TO LACK OF DEEP INSTABILITY AND MOISTURE. COOLER AND DRIER AIR FINALLY MOVES SWD INTO CWA TNGT AND PREV FCST MAX RADIATIONAL COOLING LOWS LOOK GOOD WITH GENLY CLRG SKIES EXPCD. RDG MOVES EWD OVR CWA TUE FLWD BY INCRG SSELY FLOW OF MILDER AND GRADUALLY MORE MOIST AND UNSTABLE AIR FM TUE NGT THRU WED. WILL KEEP SMALL CHCS MID LVL WARM ADVECTION TSTMS MOVG ENE OVR CWA TUE NGT AND WED MRNG. BIG MOISTURE RETURN WILL BE WED WITH STG SLY JET IN PLAINS BRINGING BACK GULF MOISTURE. SOME LOW CLOUDS COULD DVLP LATE TUE NGT INTO WED MRNG WITH THIS MOISTURE RETURN...PUTTING TEMPORARY DAMPER ON TEMP RISE ON WED... BUT NEWD MOVG WMFNT INTO CWA FLWD BY GOOD MIXING SHOULD DESTABILIZE ATMOS WED AFTN. THIS WILL LIKELY PRIME US FOR A GOOD SVR WX OUTBREAK PROBABLY IN FORM OF SUPERCELLS ALG AND NORTH OF WMFNT BY WED EVE FLWD BY A SQUALL LINE DVLPG WITH CDFNT MOVG ESEWD OVR CWA WED NGT. VERY STRONG QUASI NEG TILT UPR WAVE OUT OF RCKYS WILL INTERACT WITH LOW LVL JET WITH GOOD SHEAR AND INSTABILITY EXPCD...SO SPC MOD RISK LOOKS GOOD. LWRD POPS BEHIND FNT LATE WED NGT THRU THU NGT IN A GOOD PART OF CWA AS DRIER WLY FLOW EXPCD ALG WITH MINIMAL DYNAMICS. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ JH sd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DES MOINES IA 112 PM CDT MON JUN 4 2007 .UPDATE... UPDATED TO ADD 18Z TAF DISCUSSION. && .DISCUSSION... ONLY REAL CHANGES TO MORNING UPDATE INVOLVE TEMPS. RAISED HIGHS SEVERAL DEGREES BASED ON 15Z OBS AND SUGGESTIONS FROM FORECAST SOUNDINGS. PCPN TRENDS SEEM RIGHT ON TRACK PER EXTRAPOLATION OF CURRENT WX...REACHING FAR NWRN FCST AREA BY 19Z. CONVECTION... ELEVATED FOR THE TIME BEING...ACROSS SD/MN AHEAD OF NRN PLAINS SHRT WV WILL LIKELY EXPAND IN COVERAGE AND INTENSITY AS IT CONTINUES TO DROP SWD. TSTMS SHOULD BECOME MORE SFC BASED WITH TIME AS MLCAPE INCREASES AND CIN ERODES PER 12Z RUC/NAM. MAY SEE A FEW SVR TSTMS BUT LACK OF SHEAR SHOULD LIMIT THAT THREAT. && .PREV DISCUSSION... SUBJECTIVE SFC ANALYSIS AT 03Z SHOWS OLD LOW NEAR KMKG IN LOWER MICHIGAN. WEAK TROUGHS OF LOW PRESSURE CONTINUE TO ROTATE AROUND THE LOW WITH ONE IN SOUTHERN MO AND ANOTHER TROUGH OVER NORTHERN IA. A THIRD IS LINING UP OVER NORTH DAKOTA THROUGH NORTHERN MN TNT. ALOFT...LOW OVER THE MIDWEST HAS PHASED WITH THE REMNANTS OF TD BERRY ALONG THE EAST COAST FORMING ONE LARGE ELONGATED TROUGH FROM H850 TO H700. H500 CONTINUES TO SHOW APPROACHING WAVE NEAR LAKE WINNIPEG THAT IS EXPECTED TO IMPACT THE REGION THIS AFTERNOON AND EVENING. HT FALLS AHEAD OF THE UPPER LVL SYSTEM OVER WI ARE QUITE MEAGER AND LOW ON THE EAST COAST SHOULD SLOW THINGS DOWN A BIT...SO NOT EXPECTING MUCH EASTWARD PROGRESSION OF LOW TODAY. GFS SEEMS TO HAVE A BETTER HANDLE ON THE EXITING UPPER LOW WITH TONIGHT 00Z RUN. ATTENTION IN THE SHORT TERM CONTINUES TO FOCUS ON NEXT UPSTREAM WAVE OVER SOUTHERN CANADA NOW ENTERING EXTREME NORTHERN ND. WATER VAPOR IMAGERY SHOWS LIGHTNING FOOTPRINT ENTERING THE CONUS WITH DECENT MID LEVEL JET MAX OF 40KTS FORCING THE SYSTEM SOUTHEAST WITH TIME. BOTH NAM AND GFS NOW BACKING OFF ON TIMING OF WIND MAX REACHING THE AREA WITH 40 TO 50 KTS AFTER 06Z TUES. NONE THE LESS...GFS STILL PAINTS A 400-600 J/KG STRIPE WITH MAX VALUES APPROACHING 1000 J/KG OVER CENTRAL NE BY 00Z TUES. NAM NOT QUITE AS STRONG WITH INSTABILITY. WAVE COMBINED WITH WEAK COLD FRONTAL FORCING AND CONVERGENCE SHOULD YIELD PERIOD OF SHOWERS AND THUNDERSTORMS FROM LATE AFTERNOON THROUGH EVENING. HIGH BUILDS IN FOR TUESDAY WITH LITTLE SENS WX. SEASONAL TO SLIGHTLY BELOW NORMAL READINGS EXPECTED AS H850 TEMPS FALL TO +8 TO +11C OVER THE FORECAST AREA. MAIN SYSTEM STILL PROGGED TO ARRIVE WED WITH LEADING THETAE ADVECTION LATE TUES. MODELS STILL ADVERTISING THE WARMING ALOFT ARRIVES NEARLY CONCURRENTLY WITH LLVL MOISTURE RESULTING IN MODERATE TO HIGHLY CAPPED ENVIRONMENT. NET RESULT IS CONDITIONAL THUNDER ALONG THE LEADING EDGE MOST LIKELY WITH SOME HINT AT DEVELOPMENT OVER SOUTHERN IA/N MO AS WARM FRONT PUSHES NORTH WEDNESDAY AFTERNOON. CAP QUICKLY TAKES OVER FOR THE LATE DAY HOURS AS BULK SHEAR INCREASES NORTHWEST. GFS/GEM SHOW DEEP LOW WITH STRONG DIFFLUENCE AND NEGATIVELY TILTED TROUGH OVER EASTERN SOUTH DAKOTA DURING THE EVENING. WITH BULK SHEAR OF 60 TO 90 KTS FROM NW IA TO EASTERN NE/SD...FEEL GREATEST THREAT OF SVR WILL BE NORTHWEST PORTION OF FORECAST AREA EARLY ON WED NIGHT WITH SIGNIFICANT OUTBREAK THERE...THEN CONTINUED SEVERE EXPANDING THROUGH CENTRAL SECTIONS WHEN MORE LINEAR CONVECTION PROPAGATES EASTWARD TOWARD MORNING WITH DURING OVERNIGHT HOURS. RESULTANT SEVERE OF WIND AND HAIL FOR MOST OF REGION THOUGH MAY ALSO BE DEALING WITH SOME TORNADO THREAT DURING THE NIGHT THROUGH CENTRAL SECTIONS BASED ON CURRENT PROGS. WIND FIELDS VERY IMPRESSIVE FROM H850-H700 WITH 60KTS PROGGED OVER KDSM AT 06Z. DETAILS TO COME INTO FOCUS NEXT SEVERAL DAYS AS TIMING AND PLACEMENT ISSUES BECOME MORE SOLIDIFIED. BEYOND MAIN FROPA...SECONDARY FRONT TO PASS THROUGH THE REGION THUR NIGHT /FRIDAY WITH COOL CANADIAN HIGH TO SETTLE INTO AREA. FRONT EXPECTED TO RETURN SAT AFTERNOON/EVENING BASED ON GEM. THUS MORE WET WEATHER AS MOISTURE POOL SOUTH ADVECTS NORTH INTO REGION SO UNSETTLED WEATHER EXPECTED TO CONTINUE. && .AVIATION...04/18Z NOW HAVING SOME QUESTION ABOUT AREAL EXTENT OF APPROACHING SHWRS/TSTMS AND EVEN AMOUNT OF THUNDER. CURRENT EXTRAPOLATION WOULD SUGGEST THAT WRN TAFS...FOD/DSM...HAVE BETTER PROBABILITIES AND ARE ALSO CLOSER TO BETTER INSTABILITY SO CARRIED TEMPOS THERE AND VCNTY ELSEWHERE. ANY CIGS THAT DO LOWER IN PCPN SHOULD REMAIN VFR. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 422 PM EDT MON JUN 4 2007 .SHORT TERM...(TONIGHT AND TUESDAY) .SYNOPSIS...WV IMAGERY AND RUC ANALYSIS INDICATED A BROAD TROF OVER THE ERN CONUS A RDG FROM THE SW TO THE NRN ROCKIES AND A TROF OVER THE ERN PAC. A SLOW MOVING MID/UPPER LEVEL LOW HAD REACHED SW LOWER MI.THE AREA OF DEFORMATION AND STRONG 700-500 MB FGEN NW OF THE LOW THAT SUPPORTED BAND OF MODERATE RAIN ACROSS SE UPPER MI AND NRN LK MI WAS SLOWLY WEAKENING AND SLIDING OFF TO THE EAST. SCT SHRA HAD ALSO DEVELOPED FROM NEAR CYQT INTO NE MN AHEAD OF A TRAILING SHORTWAVE. -SHRA WERE HAVING A HARD TIME SURVIVING ACROSS THE STABLE AIR OVER N AND W LAKE SUPERIOR WHERE VIS LOOP SHOWED AREA OF CLEAR SKIES. TONIGHT...RADAR TRENDS AND 12Z NAM/RUC SUGGESTS THAT THE LINGERING AREA OF RAIN OVER THE SE WILL MOVE OUT LATE THIS AFTERNOON AND EARLY THIS EVENING WITH ONLY SCT -SHRA BTWN 00Z-03Z ALONG AND E OF GRAND MARAIS-KISQ. ALSO...ONLY ISOLD -SHRA/SPRINKLES SHOULD SURVIVE INTO FAR W UPPER MI THIS EVENING. OTHERWISE...PARTIAL CLEARING...PER 925-700 MB RH PROGS...SHOULD ALLOW TEMPS TO FALL TO NEAR 40 WITH UPPER 30S INLAND. TUE...EVEN THOUGH MLCAPE VALUES WILL BE VERY MARGINAL...100-300 J/KG AT BEST...WITH THE MID LEVEL TROF AXIS TILL NEAR E UPPER MI BY AFTERNOON AND A -23C 500 MB COLD POOL OVER THE AREA...CANNOT RULE OUT ISOLD SHRA/TSRA OVER THE SOUTH. SO...SLGT CHANCE POPS WERE RETAINED. OTHERWISE...850 MB TEMPS IN THE -1C TO 3C RANGE SUPPORT DEVELOPMENT OF SC INLAND FROM NRLY FLOW OFF LK SUPERIOR AND TEMPS RANGING FROM THE MID AND UPPER 50S EAST TO LOW 60S S AND W. EXTENDED... THE CLOSED LOW WILL REMAIN OVER HUDSON BAY TUESDAY NIGHT. ANOTHER LOW ROTATING THROUGH THE BASE OF THE CLOSED LOW WILL SHIFT FROM JUST SOUTH OF JAMES BAY INTO WEST CENTRAL QUEBEC. ANOTHER LOW OFF THE COAST OF THE PACIFIC NORTHWEST WILL DIVE INTO EASTERN OREGON. A RIDGE STRETCHES FROM THE NORTHERN PLAINS INTO NORTHERN BRITISH COLUMBIA. SEVERAL WEAK SHORTWAVES WILL SWEEP ACROSS THE FORECAST AREA. A WEAK SURFACE TROUGH WILL RACE ACROSS THE FORECAST AREA...WHILE A LARGE RIDGE BUILDS OVER THE NORTHERN PLAINS AND SOUTH CENTRAL CANADA. FORECAST SOUNDINGS INDICATE THE AIR MASS WILL BE FAIRLY DRY WITH A STRONG INVERSION AT 750MB. THIS SHOULD LIMIT THE PRODUCTION OF ANY PRECIPITATION. THE MID LEVEL LOW WILL PUSH INTO CENTRAL QUEBEC AS THE NORTHERN PLAINS RIDGE RELOCATES OVER UPPER MICHIGAN WEDNESDAY. THE CLOSED LOW OVER OREGON WILL PUSH INTO NORTHERN WYOMING. A NUMBER OF WEAK SHORTWAVES WILL SHIFT THROUGH THE BASE OF THE LOW. THE SURFACE LOW WILL MOVE INTO WESTERN NORTH DAKOTA AS A WARM FRONT LEADING THIS LOW SWEEPS INTO NORTHERN WISCONSIN. ISENTROPIC ASCENT AHEAD OF THE FRONT WILL SET OFF SOME SHOWERS. A STRONG INVERSION AROUND 750MB WILL CAP THE AIR MASS AND PREVENT ANY THUNDERSTORMS DEVELOPING LATE. THE NORTHERN PLAINS LOW WILL SHIFT INTO CENTRAL NORTH DAKOTA...WHILE THE COLD FRONT EDGES INTO WESTERN MINNESOTA WEDNESDAY NIGHT. THE CAP WILL REMAIN IN PLACE IN THE MORNING BUT BREAKDOWN DURING THE DAY. THERE APPEARS TO BE PLENTY OF MOISTURE BELOW THE INVERSION. THUS PLAN TO ONLY HAVE SHOWERS IN THE MORNING...AND SHOWERS AND THUNDERSTORMS IN THE AFTERNOON. THE MID LEVEL LOW WILL SHIFT INTO THE RED RIVER VALLEY OF THE NORTH...WHILE THE SURFACE LOW LIFTS INTO WESTERN ONTARIO ON THURSDAY. THE STRONGEST SHORTWAVE ENERGY WRAPPING AROUND THIS LOW WILL SWEEP THROUGH MINNESOTA AND EXTREME WESTERN U.P. ISENTROPIC ASCENT AND SOME LOW LEVEL MOISTURE WILL COMBINE TO GENERATE A CHANCE OF SHOWERS AND THUNDERSTORMS. THE RIDGE WILL MOVE FRONT FROM WESTERN QUEBEC TO CENTRAL QUEBEC WHILE THE LOW NEAR KINL WILL MOVE TO NORTH CENTRAL ONTARIO THURSDAY NIGHT. WEAK SHORTWAVES SWEEPING THROUGH THE BASE OF THE ONTARIO LOW WILL SWEEP THROUGH THE U.P. GFS/ECMWF SHOWING A WEAK DRY SLOT ASSOCIATED WITH THE LOW WILL MOVE THROUGH THE AREA FOLLOWED BY SOME WRAP AROUND MOISTURE. THUS WILL KEEP SOME RAIN OVER THE FORECAST AREA. MUCAPE VALUES WILL DROP OFF TO ZERO AND STABILITY INDEXES SHOWING ENOUGH INSTABILITY TO LIMIT THUNDERSTORMS. DRY AIR WILL ADVECT INTO THE SOUTHERN PART OF THE FORECAST AREA ON FRIDAY...HOWEVER...THERE WILL BE ENOUGH INSTABILITY AND MOISTURE TO CALL FOR A CHANCE OF RAIN OVER THE NORTH PORTIONS. THE MID LEVEL LOW WILL SHIFT INTO WEST CENTRAL QUEBEC WHILE A ZONAL FLOW SETS UP OVER NORTHERN CONUS AND REMAIN OVER THE AREA THROUGH SATURDAY. GUIDANCE SHOWING DRY AIR WILL BLANKET THE FORECAST AREA AS WELL THROUGH THIS SAME TIME PERIOD. A WEAK SHORTWAVE WILL SHIFT ACROSS THE FORECAST AREA ON MONDAY. GFS SHOWING AN INCREASE MOISTURE FIELD AS WELL, SO WILL ADD SHOWERS/THUNDERSTORMS TO THE GRIDS. && .MARINE... THE 12Z NAM AND RUC13 WERE PREFERRED WITH THE SLOWER DIMINISHING TREND OF NRLY FLOW ACROSS THE E 2/3 OF THE LAKE. SO...15 TO 25 KT WINDS AND WAVES IN THE 4 TO 7 FT RANGE WILL PERSIST TONIGHT BEFORE DROPPING OFF TUE MORNING. THE SLIGHTLY SLOWER MOVEMENT OF THE PLAINS LOW INTO WRN ONTARIO...PER 12Z GFS RESULTS IN DELAY IN STRONGER SE FLOW WED INTO WED NIGHT WITH WINDS VEERING SW AND W THU NIGHT INTO FRI. WAVES INTO THE 5 TO 8 FT RANGE WILL BE POSSIBLE...ESPECIALLY BY THU NIGHT AND FRI WITH GREATER MIXING BEHIND THE COLD FRONT. && .AVIATION...FOR 18Z TAF ISSUANCE DRY ADVECTION WITH NRLY FLOW WILL HELP ERODE/LIFT THE MVFR SC DECK AT KSAW BY LATE THIS AFTERNOON WITH VFR CONDITIONS PREVAILING INTO TUE AS HIGH PRES BUILD INTO THE AREA. VFR CONDITIONS SHOULD ALSO CONTINUE AT KCMX WITH CLEARING SKIES LATE TODAY. SCT/BKN SC DEVELOPING EARLY TUE EITHER WITH A WEAK SHRTWV OR DIURNAL HEATING UNDER MID LEVEL COLD POOL SHOULD REMAIN ABV 3K FT AS SFC DEWPOINTS DROP INTO THE 30S. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ EXTENDED...DLG SHORT TERM/AVIATION/MARINE...JLB mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 130 PM EDT MON JUN 4 2007 .AVIATION...FOR 18Z TAF ISSUANCE DRY ADVECTION WITH NRLY FLOW WILL HELP ERODE/LIFT THE MVFR SC DECK AT KSAW BY LATE THIS AFTERNOON WITH VFR CONDITIONS PREVAILING INTO TUE AS HIGH PRES BUILD INTO THE AREA. VFR CONDITIONS SHOULD ALSO CONTINUE AT KCMX WITH CLEARING SKIES LATE TODAY. SCT/BKN SC DEVELOPING EARLY TUE EITHER WITH A WEAK SHRTWV OR DIURNAL HEATING UNDER MID LEVEL COLD POOL SHOULD REMAIN ABV 3K FT AS SFC DEWPOINTS DROP INTO THE 30S. && .UPDATE...ISSUED 1150 AM EDT MON JUN 4 2007 WV IMAGERY AND RUC ANALYSIS INDICATED THAT THE MID/UPPER LEVEL LOW WAS SLOWLY MOVING E THROUGH SRN LAKE MI. STRONG 700-500 MB FGEN ON ITS NW FLANK SUPPORTED THE PERSISTENT AREA OF RAIN ACRS SE UPPER MI. THE 12Z NAM AND RUC SUGGEST THAT THE SUPPORTING DYNAMICS SHOULD GRADUALLY WEAKEN AND SLIDE OFF TO THE EAST. SO...ADDITIONAL RAINFALL OF AROUND 0.25-0.50 INCH MAY BE POSSIBLE OVER THE SE THIRD OF UPPER MI THIS AFTERNOON WITH THE PCPN GRADUALLY TAPERING OFF AND ENDING. SOME LOCATIONS IN FAR RURAL PORTIONS OF SW DELTA COUNTY AND EASTERN MENOMINEE COUNTY HAD RECEIVED FROM 2.5 TO 4.0 INCHES OF RAIN SINCE YESTERDAY. EXPECT POTENTIAL FOR ADDITIONAL SCT -SHRA INTO WRN LAKE SUPERIOR AND W UPPER MI THIS AFTERNOON AS A SHRTWV NW OF CYQT MOVES TOWARD THE AREA. && .PREV DISCUSSION...ISSUED 442 AM EDT MON JUN 4 2007 ADDED A SLIGHT CHANCE FOR THUNDER THROUGH 18Z TODAY FOR THE EASTERN THIRD OF THE AREA...BUT WILL KEEP ONLY SHOWERS AFTERWORDS. LOOKING BACK AT WHAT OCCURRED YESTERDAY ACROSS WESTERN MINNESOTA...ON THE BACK SIDE OF THE 500MB LOW...THIS SEEMS REALISTIC. WITH PIECES OF ENERGY CONTINUING TO ROLL THROUGH AROUND THE LARGE SCALE TROUGH TONIGHT...WILL NOT BE OUT OF THE QUESTION TO GET A COUPLE OF LIGHTNING STRIKES...BUT AT THIS TIME IT DOES NOT SEEM LIKE A GOOD ENOUGH CHANCE TO MENTION IN THE ONGOING FORECAST BEYOND THIS MORNING. IN FACT...WITH THE JUST RECENTLY UPDATED DAY1 CONVECTIVE OUTLOOK...ONLY THE EASTERN MOST FRINGE IS INCLUDED IN THE GENERAL RISK AREA. AM GOING BACK AND FORTH WITH OUR DRY FORECAST FOR THE OVERNIGHT HOURS ACROSS THE WESTERN HALF TO THIRD OF THE CWA. BELIEVE THAT THE GFS HAS BEEN DOING A RELATIVELY GOOD JOB AND WAS INITIALIZED WELL...AND DO NOT REALLY WANT TO CUT OUT ITS LOW PRECIP AMOUNTS FOR THE OVERNIGHT PERIOD. UPSTREAM...THE SYSTEM THAT MAY BRING US LIGHT PRECIPITATION IS CURRENTLY CREATING TEMPERATURES OF 32 DEGREES OF -SHSN AT CYYQ IN NORTHERN MANITOBA. THIS DOES VALIDATE THE GFS A LITTLE MORE THAN THE NAM FORECAST FOR LATE TONIGHT. STILL...ANY PRECIPITATION THAT DOES FALL IF IT DOES SHOULD BE FAIRLY LIGHT...SO WILL BE OPTIMISTIC AND KEEP THE MENTION OF ANY PROLONGED SHOWER ACTIVITY OUT AFTER 03Z TUESDAY. THE 06Z NAM ACTUALLY LOOKS VERY SIMILAR TO OUR FORECAST THAT WE JUST ISSUED...SUPPORTING THE LACK OF CHANGE. WILL A FROST ADVISORY BE NEEDED FOR TUESDAY NIGHT INTO WEDNESDAY GIVEN THE COOL TEMPERATURES AND LIGHT WINDS? WELL...IF THE NAM IS CORRECT IT VERY WELL MAY BE. HOWEVER...THE GFS WOULD KEEP MORE CLOUDS OVER THE PRIME LOCATIONS INHIBITING MUCH IN THE WAY OF FROST DEVELOPMENT. HAVE INCREASED THE AREA FOR FOG...FOR ALL AREAS WHERE MIN TEMPS WILL BE AT OR LOWER THAN 36F. BUT ONCE AGAIN...IT WILL NEED TO BE REANALYZED BY LATER SHIFTS WITH A BETTER HANDLE ON THE WIND AND SKY COVER BY LATER MODEL RUNS. CUT BACK TEMPERATURES FOR WEDNESDAY NIGHT INTO THURSDAY MORNING BY A COUPLE OF DEGREES...ESPECIALLY ACROSS THE EASTERN HALF EVEN WITH A STRONG SOUTH TO SOUTHEASTERLY BREEZE. AS FOR WEATHER DURING THIS TIME PERIOD...HAVE MADE FEW IF ANY ADJUSTMENTS. && .MARINE...4 AM ISSUANCE PATCHY FOG WILL PERSIST OVER LAKE SUPERIOR THIS MORNING AND THEN DISSIPATE BY AFTERNOON AS STRONGER NORTH WINDS BRING IN DRIER AIR FROM ONTARIO. THE GRADIENT BEHIND LOW PRESSURE DEPARTING FROM LOWER MI WILL BE TIGHT ENOUGH TO PRODUCE N WINDS GENERALLY IN THE 15 TO 25 KT RANGE WITH THE STRONGEST WINDS OVER EASTERN LAKE SUPERIOR. COLDER AIR AND EFFECTIVE MIXING OF WINDS TO THE SFC SHOULD RESULT IN 4 TO 7 FT WAVES BY LATE MON. A RIDGE BUILDING IN WILL SLACKEN GRADIENT WINDS AND BRING WAVES BACK DOWN ON TUE. A STRONG LOW DEVELOPING OVER THE NORTHERN ROCKIES BY MIDWEEK WILL MOVE TOWARD THE UPPER MISSISSIPPI VALLEY ON THU. TIGHTENING GRADIENT AHEAD OF THE APPROACHING LOW WILL RESULT IN WINDS TO AROUND 30 KT WHILE WAVES BUILD TO THE 6 TO 10 FT RANGE. SW WINDS VEERING W WILL APPROACH GALE STRENGTH THU NIGHT INTO FRI AS THE LOW AND FRONT DEPART TO THE NORTHEAST. && .MQT WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AVIATION...JLB UPDATE...JLB PREV DISCUSSION...KF MARINE...JV mi