AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE LITTLE ROCK AR 945 PM CDT SAT JUL 23 2005 .UPDATE... UPDATED FORECASTS TO REMOVE MENTION OF RAINFALL OVERNIGHT AS ALL ACTIVITY HAS DIED OUT. OTHER THAN SOME MINOR TEMPERATURE TWEAKS...REST OF PREVIOUS FORECAST LOOKS GOOD. && .PREVIOUS DISCUSSION ISSUED 157 PM CDT SAT JUL 23 2005... SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT MODELS IN VERY GOOD AGREEMENT IN THE SHORT TERM AS THEY ALL CONTINUE TO ADVERTISE MORE HOT AND DRY CONDITIONS ACROSS THE MID SOUTH. WITH MODELS IN SUCH GOOD AGREEMENT WILL NOT TRY TO SPLIT HAIRS AT THIS POINT AND GO WITH A BLEND OF FORECAST SOLUTIONS. UPPER HIGH WILL CONTINUE TO MOVE OVER THE AREA TODAY AND MAKE ONLY MINIMAL MOVEMENT TO THE EAST THROUGH THE WEEKEND...REACHING SOUTH CENTRAL TENNESSEE BY MONDAY MORNING. CURRENT VISIBLE SATELLITE SHOWING CU FIELD GOING UP OVER THE OZARKS AND OUACHITAS WITH THE HIGHER TERRAIN ACTING AS AN ELEVATED HEAT SOURCE. LATEST RUC HAS SOME AFTERNOON CONVECTION PAINTED IN OVER THE EXACT SAME AREA WHERE CUMULUS IS DEVELOPING. STILL A FEW BOUNDARIES LURKING ABOUT FOR AFTERNOON CONVECTION TO FIRE UP ON FROM LAST NIGHTS ACTIVITY. WILL ADD SHOWERS AND THUNDERSTORMS TO THE WESTERN ZONES AS AIRMASS DESTABILIZES OVER THIS AREA. CONVECTION SHOULD BE WANING EARLY AND WILL ONLY HOLD ON TO IT FOR A FEW HOURS THIS EVENING. SUNDAY LOOKS LIKE A REPEAT PERFORMANCE OF SATURDAY WITH AIR MASS A LITTLE MORE CAPPED SO WILL GO WITH A CONVECTION FREE FORECAST ON SUNDAY. WILL STILL BE ANOTHER HOT AND HUMID DAY WITH CENTER OF HIGH CRESTING OVERHEAD. WILL CONTINUE THE HEAT ADVISORY FOR SUNDAY AS WELL. NO HIGHLIGHTS IN THE FORECAST FOR MONDAY OR TUESDAY BUT ADDITIONAL HOT WEATHER EXPECTED. UPPER HIGH WILL MOVE OFF TO THE EAST ON MONDAY WITH RETURN FLOW GETTING REESTABLISHED. MODELS CONSISTENT IN BRINGING IN LOWER DEW POINTS ESPECIALLY OVER THE WEST EARLY NEXT WEEK. WILL NOT MAKE ANY CHANGES HERE AND TAKE A WAIT AND SEE APPROACH ABOUT EXTENDING THE HEAT ADVISORY. NAM SOLUTION BRINGS A SHORTWAVE UNDERNEATH THE UPPER HIGH TUESDAY WHILE GFS NOT REALLY PICKING UP ON IT. FEATURE NOT REAL IMPRESSIVE BUT IN THIS TYPE OF ENVIRONMENT...SMALL POPS ARE JUSTIFIED FOR TUESDAY AFTERNOON AND EVENING. MAV TEMPS STILL LOOK REASONABLE AND WILL BE FOLLOWED FAIRLY CLOSELY. LONG TERM...WEDNESDAY THROUGH SATURDAY NOT TOO MANY WHOLESALE CHANGES NEEDED HERE EITHER AS MODELS ONCE AGAIN IN GOOD AGREEMENT IN THE SYNOPTIC SCALE. GFS HAD BEEN THE MOST AGGRESSIVE WITH DRIVING A COLD FRONT THROUGH THE AREA EARLY IN THE PERIOD BUT LATEST RUN NOW SLOWER WITH MOVING IT THROUGH. GFS NOW APPEARS TO BE PLAYING CATCH UP WITH THE DGEX WHICH HAS CONSISTENTLY BEEN SLOWER...KEEPING THE FRONT WAFFLING AROUND NORTH ARKANSAS OR SOUTHERN MISSOURI FOR SEVERAL DAYS BEFORE IT LIMPS THROUGH LATE FRIDAY. CONFIDENCE SOMEWHAT BETTER NOW THAN DAYS PAST WITH MODELS IN BETTER AGREEMENT AND WILL GO WITH A BLEND OF THE DGEX AND GFS THIS PERIOD. THE UPPER RIDGE WHICH HAS BEEN IN CONTROL OF LATE MOVES WELL TO THE EAST BY WEDNESDAY WITH BROAD TROFFING DEVELOPING IN THE MIDDLE OF THE COUNTRY. BASED ON THE UPPER FLOW ALOFT...FRONT EXPECTED TO WAFFLE AROUND NORTHERN ARKANSAS OR SOUTHERN MISSOURI BEFORE SLOWLY SAGGING SOUTH BUT STILL ONLY REACHING THE CENTRAL PART OF THE STATE BY LATE FRIDAY. WITH FRONT IN THE GENERAL AREA THE MAJORITY OF THE PERIOD...WILL NEED TO KEEP AT LEAST SCATTERED POPS IN THE FORECAST. MODELS MOVE MAJORITY OF DEEP MOISTURE OUT BY SATURDAY AS FRONT WASHES OUT. WILL STILL HOLD ON TO SLIGHT CHANCE POPS THOUGH AS HIGH PRESSURE BUILDS OVER THE FOUR CORNERS AND SEVERAL WEAK SHORTWAVES COME THROUGH IN THE DEVELOPING NORTHWEST FLOW ALOFT. CONCERNING TEMPERATURES....INCREASED MOISTURE AND CLOUD COVER WILL KNOCK TEMPERATURES DOWN FROM VERY HOT TO JUST HOT. TEMPERATURES EXPECTED TO BE PRETTY CLOSE TO NORMAL THROUGHOUT THE PERIOD WITH WARMING ON SATURDAY AS FRONT FINALLY SHOWING SIGNS OF MOVING OUT. && .LZK WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY IN EFFECT FROM 9 PM SATURDAY UNTIL 6 PM CDT SUNDAY FOR THE FOLLOWING ZONES...ARZ003...ARZ004...ARZ005...ARZ006... ARZ007...ARZ012...ARZ013...ARZ014...ARZ015...ARZ016...ARZ021... ARZ022...ARZ023...ARZ024...ARZ025...ARZ030...ARZ031...ARZ032... ARZ033...ARZ034...ARZ037...ARZ038...ARZ039...ARZ040...ARZ041... ARZ042...ARZ043...ARZ044...ARZ045...ARZ046...ARZ047...ARZ052... ARZ053...ARZ054...ARZ055...ARZ056...ARZ057...ARZ062...ARZ063... ARZ064...ARZ065...ARZ066...ARZ067...ARZ068...AND ARZ069. && $$ 22 ar AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE LITTLE ROCK AR 157 PM CDT SAT JUL 23 2005 .SHORT TERM...TONIGHT THROUGH TUESDAY NIGHT MODELS IN VERY GOOD AGREEMENT IN THE SHORT TERM AS THEY ALL CONTINUE TO ADVERTISE MORE HOT AND DRY CONDITIONS ACROSS THE MID SOUTH. WITH MODELS IN SUCH GOOD AGREEMENT WILL NOT TRY TO SPLIT HAIRS AT THIS POINT AND GO WITH A BLEND OF FORECAST SOLUTIONS. UPPER HIGH WILL CONTINUE TO MOVE OVER THE AREA TODAY AND MAKE ONLY MINIMAL MOVEMENT TO THE EAST THROUGH THE WEEKEND...REACHING SOUTH CENTRAL TENNESSEE BY MONDAY MORNING. CURRENT VISIBLE SATELLITE SHOWING CU FIELD GOING UP OVER THE OZARKS AND OUACHITAS WITH THE HIGHER TERRAIN ACTING AS AN ELEVATED HEAT SOURCE. LATEST RUC HAS SOME AFTERNOON CONVECTION PAINTED IN OVER THE EXACT SAME AREA WHERE CUMULUS IS DEVELOPING. STILL A FEW BOUNDARIES LURKING ABOUT FOR AFTERNOON CONVECTION TO FIRE UP ON FROM LAST NIGHTS ACTIVITY. WILL ADD SHOWERS AND THUNDERSTORMS TO THE WESTERN ZONES AS AIRMASS DESTABILIZES OVER THIS AREA. CONVECTION SHOULD BE WANING EARLY AND WILL ONLY HOLD ON TO IT FOR A FEW HOURS THIS EVENING. SUNDAY LOOKS LIKE A REPEAT PERFORMANCE OF SATURDAY WITH AIR MASS A LITTLE MORE CAPPED SO WILL GO WITH A CONVECTION FREE FORECAST ON SUNDAY. WILL STILL BE ANOTHER HOT AND HUMID DAY WITH CENTER OF HIGH CRESTING OVERHEAD. WILL CONTINUE THE HEAT ADVISORY FOR SUNDAY AS WELL. NO HIGHLIGHTS IN THE FORECAST FOR MONDAY OR TUESDAY BUT ADDITIONAL HOT WEATHER EXPECTED. UPPER HIGH WILL MOVE OFF TO THE EAST ON MONDAY WITH RETURN FLOW GETTING REESTABLISHED. MODELS CONSISTENT IN BRINGING IN LOWER DEW POINTS ESPECIALLY OVER THE WEST EARLY NEXT WEEK. WILL NOT MAKE ANY CHANGES HERE AND TAKE A WAIT AND SEE APPROACH ABOUT EXTENDING THE HEAT ADVISORY. NAM SOLUTION BRINGS A SHORTWAVE UNDERNEATH THE UPPER HIGH TUESDAY WHILE GFS NOT REALLY PICKING UP ON IT. FEATURE NOT REAL IMPRESSIVE BUT IN THIS TYPE OF ENVIRONMENT...SMALL POPS ARE JUSTIFIED FOR TUESDAY AFTERNOON AND EVENING. MAV TEMPS STILL LOOK REASONABLE AND WILL BE FOLLOWED FAIRLY CLOSELY. && .LONG TERM...WEDNESDAY THROUGH SATURDAY NOT TOO MANY WHOLESALE CHANGES NEEDED HERE EITHER AS MODELS ONCE AGAIN IN GOOD AGREEMENT IN THE SYNOPTIC SCALE. GFS HAD BEEN THE MOST AGGRESSIVE WITH DRIVING A COLD FRONT THROUGH THE AREA EARLY IN THE PERIOD BUT LATEST RUN NOW SLOWER WITH MOVING IT THROUGH. GFS NOW APPEARS TO BE PLAYING CATCH UP WITH THE DGEX WHICH HAS CONSISTENTLY BEEN SLOWER...KEEPING THE FRONT WAFFLING AROUND NORTH ARKANSAS OR SOUTHERN MISSOURI FOR SEVERAL DAYS BEFORE IT LIMPS THROUGH LATE FRIDAY. CONFIDENCE SOMEWHAT BETTER NOW THAN DAYS PAST WITH MODELS IN BETTER AGREEMENT AND WILL GO WITH A BLEND OF THE DGEX AND GFS THIS PERIOD. THE UPPER RIDGE WHICH HAS BEEN IN CONTROL OF LATE MOVES WELL TO THE EAST BY WEDNESDAY WITH BROAD TROFFING DEVELOPING IN THE MIDDLE OF THE COUNTRY. BASED ON THE UPPER FLOW ALOFT...FRONT EXPECTED TO WAFFLE AROUND NORTHERN ARKANSAS OR SOUTHERN MISSOURI BEFORE SLOWLY SAGGING SOUTH BUT STILL ONLY REACHING THE CENTRAL PART OF THE STATE BY LATE FRIDAY. WITH FRONT IN THE GENERAL AREA THE MAJORITY OF THE PERIOD...WILL NEED TO KEEP AT LEAST SCATTERED POPS IN THE FORECAST. MODELS MOVE MAJORITY OF DEEP MOISTURE OUT BY SATURDAY AS FRONT WASHES OUT. WILL STILL HOLD ON TO SLIGHT CHANCE POPS THOUGH AS HIGH PRESSURE BUILDS OVER THE FOUR CORNERS AND SEVERAL WEAK SHORTWAVES COME THROUGH IN THE DEVELOPING NORTHWEST FLOW ALOFT. CONCERNING TEMPERATURES....INCREASED MOISTURE AND CLOUD COVER WILL KNOCK TEMPERATURES DOWN FROM VERY HOT TO JUST HOT. TEMPERATURES EXPECTED TO BE PRETTY CLOSE TO NORMAL THROUGHOUT THE PERIOD WITH WARMING ON SATURDAY AS FRONT FINALLY SHOWING SIGNS OF MOVING OUT. && .PRELIMINARY POINT TEMPS/POPS... LITTLE ROCK AR 76 100 75 99 / 10 10 10 10 HARRISON AR 73 98 74 96 / 30 10 10 10 HOT SPRINGS AR 75 101 75 99 / 30 10 10 10 PINE BLUFF AR 76 99 76 98 / 10 10 10 10 MOUNTAIN HOME AR 73 97 73 96 / 10 10 10 10 MONTICELLO AR 76 99 76 99 / 10 10 10 10 SEARCY AR 75 99 74 98 / 10 10 10 10 MOUNT IDA AR 74 101 76 99 / 30 10 10 10 RUSSELLVILLE AR 74 100 75 99 / 30 10 10 10 && .LZK WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY IN EFFECT FROM 1 PM SATURDAY UNTIL 6 PM CDT SUNDAY FOR THE FOLLOWING ZONES...ARZ003...ARZ004...ARZ005...ARZ006... ARZ007...ARZ012...ARZ013...ARZ014...ARZ015...ARZ016...ARZ021... ARZ022...ARZ023...ARZ024...ARZ025...ARZ030...ARZ031...ARZ032... ARZ033...ARZ034...ARZ037...ARZ038...ARZ039...ARZ040...ARZ041... ARZ042...ARZ043...ARZ044...ARZ045...ARZ046...ARZ047...ARZ052... ARZ053...ARZ054...ARZ055...ARZ056...ARZ057...ARZ062...ARZ063... ARZ064...ARZ065...ARZ066...ARZ067...ARZ068...AND ARZ069. && $$ SHORT TERM...56 / LONG TERM...56 ar AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 315 PM EDT SAT JUL 23 2005 .SHORT TERM...RADAR COVERAGE BEGINNING TO SLOWLY INCREASE THIS AFTERNOON WITH FAVORABLE CONDITIONS PRESENT FOR CONTINUED AREAL EXPANSION. RUC ANALYSIS INDICATES A LARGE AREA OF STRONG DIFFERENTIAL VORTICITY ADVECTION OVER EXTREME SOUTHEAST GEORGIA AND NORTHEAST FLORIDA...SLIDING SOUTH. BEST SURFACE CONVERGENCE THUS FAR HAS BEEN WHERE NORTHERLY FLOW ON THE BACK SIDE OF THE TROUGH AXIS IS INTERACTING WITH DEVELOPING WEST COAST SEABREEZE. PRETTY HIGH TRIGGER TEMPS ONCE AGAIN TODAY AND DESPITE THE FACT MOST AREAS ARE VOID OF CONVECTION...GOOD DYNAMICS AND PLENTY OF INSTABILITY THROUGH THE COLUMN WILL EVENTUALLY ALLOW FOR GOOD COVERAGE OF STORMS. WARM COLUMN SHOULD KEEP HAIL THREAT TO A MINIMUM...BUT WINDS COULD BECOME QUITE STRONG WITH INVERTED V SOUNDING INDICATED. MODELS CONTINUE TO ADVANCE FRONTAL BOUNDARY FURTHER SOUTH WITH SUBSEQUENT RUNS AND NORTHEAST FLOW NOW LOOKS TO SET UP OVER THE ENTIRE FORECAST AREA. ACCOMPANYING THE SURGE WILL BE SOME DRIER AIR AT THE SURFACE AND MID LEVELS. GFS LESS AGGRESSIVE WITH THESE FEATURES THAN THE NAM AND CONTINUES LIKELY POPS OVER THE EXTREME SOUTH. FEEL CONVECTION WILL AID NORTHERLY PROPAGATING OUTFLOWS TODAY...PUSHING MAIN MOISTURE AXIS TO A POSITION SIMILAR TO THE NAM. WILL THEREFORE GO WITH LOW END SCATTERED POPS FOR THE SOUTH ON SUNDAY AFTERNOON AND ISOLATED ELSEWHERE. SLIGHT INCREASE IN MOISTURE AT THE SURFACE THROUGH TUESDAY...BUT MID LEVELS SHOULD STAY DRY ENOUGH TO KEEP SLIGHT CHANCE TO LOW END SCATTERED POPS GOING THROUGH MID WEEK. LOOKS AS THOUGH DRIER AIR (LOWER 70S DEWPOINTS VS MID 70S) WILL PREVENT ANY HEAT INDEX VALUES ABOVE 105. THIS IS DESPITE TEMPERATURES IN THE UPPER 90S OVER THE NORTHERN ZONES SO DRY AIR EVOLUTION WILL NEED TO BE MONITORED CLOSELY. .LONG TERM...RIDGE AXIS TO RE-ESTABLISH ITSELF OVER THE AREA BY MID- WEEK WITH INCREASING MOISTURE AND MORE IN THE WAY OF CLIMO POPS. CURRENT GRIDS REFLECT THIS WELL AND LITTLE CHANGE WILL BE MADE. && .MARINE...NORTH TO NORTHEAST WINDS WILL INCREASE BEHIND THE WEAK COLD FRONT MOVING THRU THE AREA TONIGHT. HOWEVER...WINDS AND SEAS WILL REMAIN BELOW CAUTION CRITERIA. SWELLS FROM FRANKLIN ARE EXPECTED TO SLOWLY SUBSIDE SUN...ALTHO THE MOTION AND STRENGTH OF THE SYSTEM WILL AFFECT THIS DECREASE. && .PRELIMINARY POINT TEMPS/POPS... AMG 74 98 73 98 / 10 20 10 20 SSI 79 91 79 92 / 20 20 10 10 JAX 75 93 73 93 / 30 20 10 10 SGJ 76 90 76 90 / 40 30 20 20 GNV 74 94 72 95 / 50 30 20 20 OCF 74 94 73 93 / 50 40 30 30 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. MARINE...NONE. && $$ PUBLIC...DEESE MARINE/FIRE WX...CARROLL fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 1000 AM EDT SAT JUL 23 2005 .CURRENT...A WEAK TROF DROPPED SOUTH FROM NORTHERN ALABAMA AND GEORGIA KICKING OFF SOME THUNDERSHOWERS OVER SOUTHERN GEORGIA LAST NIGHT. THE SURFACE TROF REMAINS BEHIND OVER SOUTHERN GEORGIA FROM SAVANNAH THROUGH MACON. HOWEVER THE U/L TROF CONTINUED SOUTH ACROSS NORTHERN FLORIDA AND HAS ENTERED THE NORTHERN GULF OF MEXICO. WITH ADVANCING PVA ASSOCIATED WITH THE U/L TROF...A LINE OF THUNDERSHOWERS ARE REDEVELOPING AHEAD OF THE U/L TROF IN THE OFF-SHORE WATERS AND MOVING SOUTH. BEHIND THE U/L TROF RUC SHOWS NORTHERLY WIND FLOW AND DRIER AIR MOVING SOUTH INTO GEORGIA AND ALABAMA. THE TLH SOUNDING FROM BOUNDARY LAYER TO 500MB SHOWS BACKING WINDS AND A DRY LAYER AROUND 700MB. PWS STILL AROUND 2.07 INCHES THIS MORNING AND LI OF -6. MODIFIED SOUNDING SHOWS LI OF -7.45 WITH MAX TEMP OF 95F. HOWEVER...DRIER MID-LEVEL AIR COMBINED WITH SOME SUBSIDENCE WILL HELP TEMPER CONVECTIVE ACTIVITY THIS AFTERNOON OVER LAND AREAS. OFF-SHORE THUNDERSHOWERS WILL BE PERSISTENT AHEAD OF THE U/L TROF IN THE GULF OF MEXICO. NO CHANGE EXPECTED IN ZONES. && .MARINE... OFFSHORE FLOW HAS BECOME WESTNORTHWEST AND IS EXPECTED TO BECOME NORTHWESTERLY THIS EVENING IN ASSOCIATION WITH THE UPPER TROUGH. A LINE OF THUNDERSHOWERS WILL CONTINUE TO MOVE SOUTH THROUGH THE OFF-SHORE WATERS THIS AFTERNOON AHEAD OF THE U/L TROF. WINDS ARE RUNNING ABOUT WESTNORTHWEST ABOUT 10 TO 12 KNOTS AND SEAS ARE 2 FOOT OR LESS THIS MORNING. NO CHANGES EXPECTED IN MARINE FORECAST EXPECTED. && .FIRE WEATHER... NO CONCERNS. && .AVIATION... THERE IS ONE LONE THUNDERSTORM MOVING SOUTH IN THE OFF-SHORE WATERS NOT CURRENTLY AFFECTING TWEB ROUTES OR TERMINALS. ONLY LIGHT FOG WITH MVFR VISIBILITIES OCCURRED THIS MORNING. LOWEST VISIBILITY OCCURRED AT VLD WITH 3NM. DHN AND ABY REACHED 5NM AND PFN ONLY DROPPED TO 6NM. THE LINE OF +TSRA IN THE NORTHERN GULF OF MEXICO MAY GROW FAR ENOUGH EASTWARD THIS AFTERNOON TO AFFECT TWEB ROUTE 117. OVERLAND...ISOLD TO SCT +TSRA WILL ONCE AGAIN DEVELOP DURING THE AFTERNOON AND EARLY EVENING HOURS POSSIBILITY PRODUCING IFR/MVFR CONDITIONS AT OUR TAF SITES AND ALONG TWEB ROUTES 112 AND 117. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ SHORT/LONG TERM: WATSON AVIATION: LANIER fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 202 PM MDT SAT JUL 23 2005 .SHORT TERM... (TONIGHT - TUESDAY) FORECAST PROBLEMS WILL BE INCREASING CONVECTIVE CHANCES AND HIGH TEMPERATURES. WIND ADVISORY MAY NEED TO BE CONSIDERED LATE THIS AFTERNOON/EARLY THIS EVENING AND AGAIN ON SUNDAY EAST OF THE SURFACE TROUGH. TONIGHT/SUNDAY...UPPER RIDGE FORECAST TO SHIFT EASTWARD DURING THIS PERIOD...OPENING THE DOOR FOR SHORTWAVE ENERGY ROTATING AROUND ITS PERIPHERY TO INTRODUCE CONVECTION INTO THE FORECAST AREA. RIDGE WILL HOLD FIRM TONIGHT AND MOST ACTIVITY WILL BE CONFINED TO EXTREME NORTHERN COLORADO AND NEBRASKA PANHANDLE. MAY KEEP A SLIGHT MENTION IN THE FAR NORTHWEST CORNER...BUT OTHERWISE DRY. DEVELOPMENTAL RUC INCREASING WINDS ACROSS MOST OF THE FORECAST AREA 21Z TO 03Z TODAY TO THE 30-35KT SUSTAINED RANGE. MCCOOK AND SPRINGFIELD PROFILERS ALREADY SHOWING 45KT JUST OFF THE SURFACE 18Z-20Z...BUT GLD AND DDC VWPS LESS. WILL HAVE TO MAKE A LAST MINUTE CALL ON POTENTIAL WIND ADVISORY. ON SUNDAY LATE AFTERNOON AND EVENING CONVECTION WILL FIRE FURTHER EAST ALONG PERSISTENT SURFACE BOUNDARY...AIDED BY WEAK VORT MAXES ROTATING AROUND THE UPPER RIDGE. SLIGHT/LOW CHANCE POPS WILL SPREAD EASTWARD SUNDAY NIGHT AND WILL HAVE A MENTION EVERYWHERE EXCEPT FAR SOUTH/EASTERN AREAS. FORECAST 850MB TEMPERATURES NEARLY IDENTICAL TO SATURDAY...SO WENT A BIT ABOVE MOS GUIDANCE. MONDAY/TUESDAY...BOUNDARY/PRE FRONTAL TROUGH WILL HANG UP ACROSS THE CWA ON MONDAY. POSITION OF RIDGE WILL ALLOW SUBTLE SHORTWAVE ENERGY TO ROTATE THROUGH AS WELL FROM COLORADO. HARD TO RULE OUT AT LEAST A SLIGHT CHANCE OF THUNDERSTORMS. 850MB TEMPERATURES DROP A DEGREE OR TWO CELSIUS...BUT CONTINUE TO SUPPORT UPPER 90S WEST TO LOWER 100S EAST. MONDAY NIGHT AND TUESDAY PRESENT TOUGHEST FORECAST CHALLENGE...BOTH WITH PRECIPITATION CHANCES AND TEMPERATURES. GFS LOOKS OVERDONE ON THE FORMER...AND APPEARS TO BE SUFFERING FROM TYPICAL UPSLOPE WET BIAS. NONETHELESS STRONG COLD FRONT WILL PUSH THROUGH MONDAY NIGHT. NORTHERN ZONES APPEAR BEST SITUATED TO UPPER DYNAMICS SO WILL HAVE HIGHEST POPS THERE. FRONT WILL CONTINUE TO PUSH SOUTH DURING THE DAY ON TUESDAY. MODELS ARE COLD AND WET...ESPECIALLY THE GFS. ONCE AGAIN THINK BOTH THOSE FIELDS ARE OVERDONE/SUFFERING FROM CONVECTIVE FEEDBACK. WILL GO CLOSER TO ECMWF 850MB TEMPERATURES...WHICH ARE 5 TO 8 C WARMER THAN THE OTHER MODELS...WITH BIAS APPLIED. WILL HOLD ON TO A RATHER BROADBRUSHED 20 POPS TUESDAY AND TUESDAY NIGHT...TO BLEND WITH SURROUNDING OFFICES...BUT ALSO TO REFLECT LOW CONFIDENCE IN THE MODELS. .LONG TERM... (WEDNESDAY - SATURDAY) UPPER PATTERN OVER THE CONUS THIS PERIOD WILL FEATURE RIDGE NEAR THE FOUR CORNERS AND TROUGH NEAR THE GREAT LAKES. A COUPLE OF STRONG NORTHERN STREAM SHORTWAVES WILL MOVE THROUGH THE MEAN TROUGH POSITION...HOWEVER ASSOCIATED SURFACE FRONTS WILL NOT HAVE ENOUGH PUSH TO AFFECT THE LOCAL FORECAST AREA. NONETHELESS...MUCH COOLER TEMPERATURES WILL BE EXPERIENCED IN THE WAKE OF TUESDAYS STRONG COLD FRONT. HAVE COOLED OFF BOTH MAX AND MINS TO STAY IN LINE WITH LATEST GUIDANCE. IN FACT 850MB TEMPERATURES CURRENTLY SUPPORT ONLY 70S FOR HIGHS ON WEDNESDAY. PRECIPITATION CHANCES WILL BE TIED TO THE LOW LEVEL UPSLOPE FLOW THAT DEVELOPS AS SURFACE HIGH GRADUALLY SLIDES OFF TO THE EAST. MOISTURE WILL BE LIMITED EARLY IN THE PERIOD WITH FRONT OVER THE RED RIVER VALLEY...BUT BOUNDARY LAYER WILL RECOVER BY THE END OF THE WEEK. CONVECTIVE DEVELOPMENT WILL ALSO BE AIDED BY SHORTWAVES ROTATING AROUND THE FOUR CORNERS RIDGE. FOR NOW WILL LIMIT 20 POPS TO FAVORED HIGH-TERRAIN AREAS IN WESTERN ZONES DURING AFTERNOON AND EVENING HOURS. .GLD WATCHES/WARNINGS/ADVISORIES... .KS...NONE. .NE...NONE. .CO...NONE. && $$ JDK ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 450 PM EDT FRI JUL 22 2005 .DISCUSSION... BIG CONCERN FOCUSES ON POTENTIAL FOR MCS DEVELOPMENT AND ASSOC CONVECTION TO MOVE IN FROM THE NRN PLAINS AND CHC FOR SVR STORMS. MCS AND DERECHO WHICH FORMED OVER NRN PLAINS EARLIER THIS MORNING HAS FOLLOWED 850-300 MB THCKNS...850 MB WARM FRONT AND JUICY UPR 60S/LOW 70S SFC DWPNTS INTO WI. FRINGE OF THIS CONVECTION HAS GRACED WI BDR COUNTIES WITH SOME LIGHT RAIN THIS AFTERNOON BUT IT LOOKS LIKE MUCH OF ZONES WILL BE MISSED BY THIS CONVECTION FOR EARLY EVENING. UPSTREAM CONVECTION FIRING OVER NE ND/NW MN AS NOTED ON REGIONAL RADAR LOOP WILL BE MAIN FOCUS FOR POSSIBLE MCS DEVELOPMENT AND RAIN/ SVR WX CHCS FOR U.P LATER THIS EVENING. TONIGHT...MODELS SHOW MID-LEVEL HEIGHT FALLS WILL OCCUR ACROSS THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY AHEAD OF SHORTWAVE MOVING IN FM SASKATCHEWAN/MONTANA. IN RESPONSE TO THE APPROACHING SHORTWAVE...STRONG LOW LEVEL WARM ADVECTION SHOULD CONTINUE DUE TO THE STRENGTHENING 45-50 KT LOW LEVEL JET AND DAYTIME HEATING. AS A RESULT...MODELS INDICATE THE 850MB WARM FRONT SHOULD REACH CENTRAL MINNESOTA BY 00Z AND THE WI/UPR MI BDR BY 06Z. EXTREME INSTABILITY WITH MLCAPES APPROACHING 4000 J/KG ARE FCST BY RUC AND NAM LATER TODAY OVER THE NRN PLAINS AS DAYTIME HEATING ERODES CAP. LOOK FOR MCS TO FORM OVR EASTERN NORTH DAKOTA AND NORTHERN MINNESOTA THIS EVENING. RUC CORFIDI VECTORS AND 850-300MB THICKNESS FIELD SUGGESTS THIS MCS WILL PROPAGATE SEWD AND MAY CLIP THE U.P/WI BDR COUNTIES LATER THIS EVENING. THIS IS ALSO SIMILAR TO WHAT THE 12Z NAM AND UKMET AND EXPERIMENTAL WRF RUN FROM NCAR WOULD INDICATE. FOR A FORWARD PROPAGATING MCS...THE NEWER CORFIDI VECTOR METHOD INDICATES VELOCITIES OF 70-80KT...DEFINITELY SUGGESTING A DAMAGING WIND AS MAIN THREAT FROM A POTENTIAL DERECHO. A STRONG UNIDIRECTIONAL MID-LVL FLOW PARALLEL IN DIRECTION TO QUASISTATIONARY SFC WARM FRONT JUST TO SOUTH ALSO WOULD ARGUE FOR POSSIBLE DERECHO OR BOW ECHO DVLPMT. NOT SURPRISINGLY...SPC DAY 1 OUTLOOK SHOWS MODERATE RISK OF SVR STORMS BORDERING FAR WRN U.P WITH A SLGT RISK WEST OF A MQT-ISQ LINE. HIGH WET-BULB ZERO HEIGHTS OF 12 KFT OR HIGHER WOULD SUGGEST HAIL NOT AS MUCH OF A THREAT BUT STILL CAN'T RULE IT OUT ENTIRELY IF ISOLD SUPERCELL SPINS UP ALONG BOWING LINE. GIVEN ABOVE SCENARIO WILL PUT LIKELY POPS IN FOR MUCH OF WEST AND CENTRAL COUNTIES WITH HIGHER CHC POPS IN FOR THE KEWEENAW PENINSULA AND ERN COUNTIES. SUN...ANY LEFTOVER SHRA/TSRA SHOULD DEPART EARLY AS STRONG MID LVL DRYING FOLLOWS IN THE WAKE OF SHORTWAVE AND ASSOC DEPARTING COLD FRONT. STILL EXPECT TEMPS TO CLIMB AOA GUIDANCE...ESPECIALLY FOR LOCATIONS FAVORED BY WNW DOWNSLOPE FLOW AS WITH H8 TEMPS FCST TO NEAR 20C AND PLENTY OF SUNSHINE/MIXING. MON INTO MON NIGHT...ALL 12Z MODELS INDICATE SHORTWAVE MOVING IN FROM THE WEST MON AFT WITH INCREASING WAA/ISENTROPIC LIFT AT 850 MB IN RESPONSE TO RIGHT ENTRANCE REGION FORCING FROM STRENGTHENING 110 KT 3H JET NORTH OF LAKE SUPERIOR. ISENTROPIC LIFT/WAA WOULD FAVOR BEST CHC OF CONVECTION OVER SCNTRL AND ERN COUNTIES LATE MON AFTERNOON INTO MON NIGHT. HAVE BUMPED UP POPS HERE TO 40 PCT WITH 30 PCT POPS TO NORTH AND WEST. TUE...FOLLOWING SLIGHTLY SLOWER UKMET SOLN WITH DEPARTURE OF SFC TROF/CDFNT...KEPT IN LINGERING CHC POPS FOR FAR ERN COUNTIES IN THE MORNING WITH OTHERWISE HAVE DRY CONDS TO WEST. EXTENDED (WED-SAT)...12Z GFS TRENDING WEAKER WITH SHORTWAVE AND ASSOC CDFNT FOR WED NIGHT INTO THU WHILE 12Z ECMWF SOLN PERHAPS A BIT MORE AMPLIFIED WITH SHORTWAVE INTO UPR GRT LAKES. GIVEN UNCERTAINTY WILL MAINTAIN DRY FCST FOR NOW WED INTO THU. WITH OPERATIONAL MODELS SHOWING ANOTHER SHORTWAVE DIVING INTO THE NRN PLAINS LATE IN WEEK KEPT IN CHC OF TSRA FOR FRI AND SAT. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VOSS mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1048 AM EDT FRI JUL 22 2005 .DISCUSSION... COMPLEX FORECAST UPDATE WITH CONVECTIVE POTENTIAL THIS AFTERNOON AND TONIGHT. SEVERE WEATHER IS ALSO A CONCERN. 14Z WATER VAPOR LOOP AND 12Z RAOBS SHOWED THE MAMMOTH HEAT RIDGE ACROSS THE CENTRAL PLAINS WITH A 598 DAM HIGH CENTERED OVER TOPEKA KANSAS. 850MB TEMPS OBSERVED RANGED FROM 25-31C UNDER THE RIDGE. THE ASSOCIATED RIDGE AXIS EXTENDED NORTHWARD TO LAKE WINNIPEG. TWO MCS\S ARE CURRENTLY OCCURRING ALONG THE RIDGE...ONE OVER WEST CENTRAL MN AND THE OTHER NEAR LACROSSE WISCONSIN. THESE MCS\S ARE RIDING VERY CLOSE TO A SURFACE WARM FRONT WHICH EXTENDS FROM A LOW NEAR PIERRE SOUTH DAKOTA DOWN TO SW MN TO NEAR WATERLOO IOWA. BEST PRESSURE FALLS HOWEVER ARE OCCURRING MUCH FURTHER NORTH...OVER NE NORTH DAKOTA. THESE FALLS ARE IN RESPONSE TO HEIGHT FALLS FROM A SHRTWV MOVING E FROM MONTANA/SASKATCHEWAN. RUC ANALYSIS ALSO INDICATES A SHRTWV OVER WESTERN NORTH DAKOTA WHICH IS HARD TO SEE IN WATER VAPOR. PROFILER NETWORK DOES SHOW A 35KT LOW LEVEL JET AT 850MB EXTENDING FROM NW KANSAS INTO THE SIOUX FALLS AREA. CLOSER TO HOME...A BAND OF SCATTERED SHOWERS AND A FEW THUNDERSTORMS EXTENDED FROM NORTHERN MN INTO NE WISCONSIN. THIS BAND WAS LOCATED IN A REGION OF ISENTROPIC LIFT ON THE 310K SURFACE...ALSO ON A TIGHT GRADIENT OF 850MB THETA-E. THIS AFTERNOON...MAIN CONCERN FOR UPPER MICHIGAN EARLY IS THE BAND OF ISENTROPIC LIFT SHOWERS AND ISOLATED -TSRA. THE 12Z NAM HAS A GOOD HANDLE ON THIS...SHOWING THE 850MB THETA-E GRADIENT PROGRESSING NE AND BECOMING LESS TIGHT. THIS WOULD SUGGEST A WEAKENING OF THE CONVECTION...WHICH SEEMS REASONABLE GIVING THAT THIS CONVECTION IS SOMEWHAT NOCTURNAL. IN FACT...THE NAM QPF FIELD BETWEEN 15-18Z DOES SHOW A WEAKENING WITH ONLY A LITTLE BIT OVER THE FAR WEST. THEN THE NAM INITIATES CONVECTION FROM NORTHERN MN INTO NW WI BETWEEN 18-21Z. 12Z RUC DOES SOMETHING SIMILAR AND IT APPEARS IT IS ALSO RELATED TO MORE ISENTROPIC LIFT. THEREFORE FOR THE FORECAST WILL MAINTAIN A CHANCE FOR SHOWERS AND THUNDERSTORMS ALONG THE WISCONSIN BORDER. OTHERWISE...850MB TEMPS OF 14-16C SUGGEST MAX TEMPERATURES IN THE LOW 80S AWAY FROM LAKE MICHIGAN AND THICKER CLOUD COVER. TONIGHT...MID-LEVEL HEIGHT FALLS WILL OCCUR ACROSS THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY AS THE SASKATCHEWAN/MONTANA SHRTWV APPROACHES AND THE OTHER HARD TO SEE SHRTWV MOVES ACROSS THE RIDGE. LOW LEVEL WARM ADVECTION SHOULD CONTINUE UNDERNEATH THESE MID-LEVEL HEIGHT FALLS DUE TO THE LOW LEVEL JET AND DAYTIME HEATING. AS A RESULT...THE 850MB WARM FRONT IS PROGGED TO REACH CENTRAL MINNESOTA BY 00Z. CONVECTION OVER WEST CENTRAL MN IS NOT EXPECTED TO BE A FACTOR IN THIS NORTHWARD MOVEMENT OF THE WARM FRONT SINCE MUCH OF THAT CONVECTION WILL PROGRESS INTO SW WI THIS AFTERNOON INTO THE BETTER ELEVATED INSTABILITY (WHERE CAPES AT THE MOMENT ARE 2500 J/KG LIFTED FROM 500MB PER SPC MESOSCALE ANALYSIS PAGE). WITH THE JUXTAPOSITION OF WARM ADVECTION UNDER MID-LEVEL HEIGHT FALLS...WOULD EXPECT CONVECTION TO INITIATE AGAIN THIS EVENING OVER EASTERN NORTH DAKOTA AND NORTHERN MINNESOTA. WITH PLENTY OF INSTABILITY ALONG THE 850MB WARM FRONT DUE TO HOT AND HUMID TEMPERATURES GETTING ADVECTED FROM THE PLAINS...WOULD EXPECT AN MCS TO FORM. CORFIDI VECTORS AND 850-300MB THICKNESS FIELD SUGGESTS THIS MCS WILL PROPAGATE INTO NORTHERN MN AND THEN INTO THE WESTERN U.P. PERHAPS LATE THIS EVENING OR OVERNIGHT. THIS IS VERY SIMILAR TO WHAT THE 00Z UKMET...06Z NAM...EXPERIMENTAL WRF RUN FROM NCAR AND OUR LOCAL WRF RUN INDICATE. NEW 12Z NAM IS ALSO SIMILAR TO THIS IDEA WITH PERHAPS A SLIGHT ADJUSTMENT SOUTH IN COMPARISON TO THE 06Z RUN. FOR A FORWARD PROPAGATING MCS...THE NEWER CORFIDI VECTOR METHOD INDICATES VELOCITIES OF 70-75KT...DEFINITELY SUGGESTING A DAMAGING WIND THREAT FROM A POTENTIAL DERECHO DESPITE ANY SORT OF SURFACE BASED INVERSION THAT MAY FORM. SPC DAY 1 OUTLOOK SHOWS A 25% PROBABILITY OF SEVERE WIND ACROSS THE CWA WITH A 10% PROBABILITY OF SIGNIFICANT WIND DAMAGE INTO GOGEBIC COUNTY. EVEN BEFORE THIS CONVECTION COMES INTO THE U.P....WE MAY STILL BE DEALING WITH THAT INITIAL CONVECTION PROGGED TO FORM LATE THIS AFTERNOON...WHICH SHOULD MOVE NORTHEAST ACROSS THE CWA THIS EVENING. MAIN CHANGE WILL BE TO UP POPS TO LIKELY ALONG THE WISCONSIN BORDER. A HISTORICAL REFERENCE NOTE...THERE ARE MANY SIMILARITIES BETWEEN THIS UPCOMING EVENT AND AUGUST 1ST OF 2002...ALTHOUGH AT THE TIME MUCH MORE MOISTURE WAS ALREADY INTO UPPER MICHIGAN (DEWPOINTS IN THE UPPER 60S TO LOW 70S). UPDATE TO HWO WILL BE COMING OUT AROUND NOON. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AJ mi AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE JACKSON MS 907 PM CDT SAT JUL 23 2005 .DISCUSSION... ONLY ISOLATED SHRA THIS EVENING IN MARION COUNTY AND HEAT INDEXES FINALLY DROPPED BELOW 105 LEVEL AT 8 PM ALONG AND N OF I-20. HOT DOME OF HIGH PRESSURE(597DM @500MB) SITUATED OVER ERN MO AND HEADING SEWD. RUC PLACES CENTER IN WRN TN SUNDAY MORNING WITH EXPANDING -4C 500MB TEMPERATURES OVER MS/AL. EXPECT SOME 100F SURFACE HIGHS IN NERN MS ON SUNDAY WITH HEAT INDEXES PUSHING 115F WHERE HEAT WARNING IN PLACE - WILL HAVE TO WATCH FOR POSSIBLE LOWER DEWPOINTS IF NAM CORRECT. SHORT UPDATE TO KEEP ISOLATED SHRA OVERNIGHT IN SERN CORNER WHERE MODELS INDICATING AN INVERTED UPPER TROUGH AXIS WILL SLIDE WWD FROM THE NW FL COAST. SOME ADDITIONAL CLOUD COVER OVER THE EXTREME SRN PORTIONS OF THE CWFA ON SUNDAY COULD EASE THE NEED FOR HEAT ADVISORY IN THOSE AREAS EVEN THOUGH POPS WILL BE VERY LOW THROUGH SUNDAY. GRIDS/GRAPHICS/ZONES WILL BE OUT SHORTLY. && .PRELIMINARY POINT TEMPS/POPS... JACKSON 75 98 75 97 / 10 10 10 10 MERIDIAN 73 98 74 98 / 10 10 0 20 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...EXCESSIVE HEAT WARNING UNTIL 7 PM SUNDAY FOR MSZ030-MSZ031- MSZ033. HEAT ADVISORY FROM 7 PM SUNDAY TO 7 PM MONDAY FOR MSZ030-MSZ031- MSZ033. HEAT ADVISORY UNTIL 7 PM MONDAY FOR MSZ018-MSZ019-MSZ025-MSZ026- MSZ027-MSZ028-MSZ029-MSZ032-MSZ034-MSZ035-MSZ036-MSZ037- MSZ038-MSZ039-MSZ040-MSZ041-MSZ042-MSZ047. HEAT ADVISORY FROM 10 AM SUNDAY TO 7 PM MONDAY FOR MSZ043-MSZ044- MSZ045-MSZ046-MSZ048-MSZ049-MSZ050-MSZ051-MSZ052-MSZ053- MSZ054-MSZ055-MSZ056-MSZ057-MSZ058-MSZ059-MSZ060-MSZ061- MSZ062-MSZ063-MSZ064-MSZ065-MSZ066-MSZ072-MSZ073-MSZ074. LA...HEAT ADVISORY UNTIL 7 PM MONDAY FOR LAZ007-LAZ008-LAZ009-LAZ015- LAZ016-LAZ023-LAZ025. HEAT ADVISORY FROM 10 AM SUNDAY TO 7 PM MONDAY FOR LAZ024-LAZ026. AR...HEAT ADVISORY UNTIL 7 PM MONDAY FOR ARZ074-ARZ075. && $$ 40 ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NORTH PLATTE NE 1220 PM CDT SAT JUL 23 2005 .DISCUSSION... CURRENT TEMPS RUNNING ABOVE FCST BY A FEW DEGREES ESPECIALLY NORTH. NAM SHOWS MAX THICKNESSES ACROSS NC NEB INTO SD WITH FCST VALUES OF 592.5 DAM. THESE ARE LARGER THAN THICKNESSES FCST YESTERDAY IN SW CWA WHICH SAW KIML HIT 109. SFC ANALYSIS PLACES LOW OVER C SD WHICH IS PRIME FOR MAX HEATING KVTN EAST. HAVE BUMPED UP TEMPS IN THE NC AND NE ZONES. ALSO...BOTH RUC AND NAM BRINGING WINDS UP TO ADVISORY CRITERIA IN NE ZONES AS PRES GRAD MAG INCREASES AHEAD OF SFC TROUGH. WILL ISSUE WIND ADVISORY FOR THIS AFTERNOON ZONES EAST OF HIGHWAY 83 IN NC/NE NEB. EXPECTING SUSTAINED WINDS IN 25-35 MPH RANGE. NO OTHER CHANGES MADE. .PREV DISCUSSION... 500 MB HEIGHT OF 600 CENTERED THIS MORNING OVER SOUTHWEST NEBRASKA. THIS RIDGE OF HIGH PRESSURE HAS BEEN SLOWLY PROGRESSING FROM WEST TO EAST OVER THE PAST FEW DAYS WITH NUMEROUS SITES EXCEEDING 100 DEGREES UNDERNEATH IT. TODAY WILL BE NO EXCEPTION...AND MAY BE THE HIGHEST OF THE WEEK FOR MANY LOCATIONS. CLOUDS WILL BE LIMITED AND THE DRY SURFACE SHOULD SUPPORT MANY 100+ TEMPERATURES. MODELS HAVE NOT BEEN HANDLING LL MOISTURE VERY WELL THUS HAVE GONE WITH MORE OF A PERSISTENCE FORECAST. THIS WILL RESULT IN VERY LOW RH VALUES ESPECIALLY ACROSS THE SOUTHWEST...AROUND 15 PERCENT. SURFACE TROUGH WILL BEGIN TO ENTER THE NORTHWEST LATER TODAY...HOWEVER WINDS AHEAD OF THE TROUGH GOING TO BE A BIT ON THE BREEZY SIDE. WILL HAVE DAY SHIFT MONITOR FOR POSSIBLE RED FLAG CONDITIONS. ATM LOOKS TO REMAIN SLIGHTLY BELOW THE FREQUENT WINDS ABOVE 25 MPH. TONIGHT THE TROUGH WILL STALL ACROSS THE NORTHWEST ZONES AND WILL HAVE THE POTENTIAL TO PRODUCE SOME ISOLATED THUNDERSTORMS. RIDGE MAY BE STRONG ENOUGH TO INHIBIT BUT AFTER WATCHING THE DAKOTAS OVER THE PAST SEVERAL HOURS...THINK SMALL POPS ARE WARRANTED. MAJOR DISCREPANCIES AFTER TONIGHT BETWEEN THE MODELS AS TO THE LOCATION AND SPEED OF THE TROUGH HEADING SLOWLY SOUTH ACROSS THE FORECAST AREA. HAVE GONE WITH MORE OF A BLEND OF MODELS AND PREVIOUS FORECAST. SUNDAY MONDAY GOING TO CONTINUE TO BE HOT SOUTH OF THE TROUGH...HOWEVER NEAR AND NORTH OF THE TROUGH WILL BE AN AREA THAT NEEDS TO BE WATCHED. TROUGH WILL SUPPORT SOME LIFT AND MAY LEAD TO A PARTLY TO MOSTLY CLOUDY DAY WITH HIGHS STRUGGLING TO GET OUT OF THE 80S. AFTER SEEING HIGHS WELL INTO THE 90S AND LOW 100S AND THE SURFACE SLOWLY DRYING OUT...AM HARD PRESSED TO SEE CLOUDS ALL DAY. SOME RELIEF OF HOT CONDITIONS IS EXPECTED BY MIDWEEK AS TROUGH/COLD FRONT WILL PUSH THROUGH THE AREA BY TUESDAY MORNING. THIS WILL RETURN HIGHS TO MORE SEASONAL TEMPERATURES (MID TO UPPER 80S)...HOWEVER LIMITED MOISTURE WARRANTS LITTLE TO NO MENTION OF RAIN. && LBF WATCHES/WARNINGS/ADVISORIES...WIND ADVISORY UNTIL 01Z NEZ006- 010>026-029. && $$ MASEK/JMC ne AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE ALBANY NY 840 PM EDT SAT JUL 23 2005 .SHORT TERM (REST OF TONIGHT)... BELIEVE IT OR NOT...A QUICK UPDATE TONIGHT TO ACCOUNT FOR A FEW SHOWERS MOVING INTO NORTHERN HERKIMER AND HAMILTON COUNTIES. THE SHOWERS ARE ASSOCIATED WITH A WEAK 500 MB SHORTWAVE/VORT MAX DEPICTED BY THE 40KM RUC IN THE NW FLOW. THESE SHOWERS SHOULD WEAKEN CONSIDERABLY WITH THE LOSS OF THE DAYTIME HEATING. CLOUDS WERE INCREASED OVER THE SRN ADIRONDACKS AND THE CNTRL MOHAWK VALLEY. NO OTHER CHANGES. SHORT TERM...WASULA && .PREVIOUS DISCUSSION... (ISSUED 320 PM EDT SAT JUL 23 2005) SHORT TERM (TONIGHT THROUGH SUNDAY)...BIG BREAK IN HEAT AND HUMIDITY TODAY. HIGH PRESSURE WILL CONTINUE TO BUILD INTO THE REGION THIS WEEKEND. LATEST SURFACE OBSERVATIONS SHOWING TEMPERATURES IN THE MID TO UPPER 70S WITH DEWPOINTS IN THE MID TO UPPER 50S. SATELLITE PICTURE SHOWING SCATTERED MID LEVEL CLOUDS ACROSS THE REGION. WILL CONTINUE WITH DRY FORECAST THE NEXT TWO DAYS AND TEMPERATURES SLIGHTLY BELOW NORMAL TODAY AND TOMORROW. LONG TERM (SUNDAY NIGHT THROUGH SATURDAY)...BY SUNDAY NIGHT/EARLY MONDAY A WEAK FRONT WILL PUSH THROUGH THE REGION. THE QPF ASSOCIATED WITH THE FRONT AT THIS TIME DOES NOT LOOK OVERLY IMPRESSIVE. WILL CONTINUE WITH A LOW CHANCE OF SHOWERS AND THUNDERSTORMS SUNDAY NIGHT AND ON MONDAY. THE WARM AIR AND HUMIDITY WILL BE ON THE INCREASE EARLY IN THE WEEK AS A HIGH PRESSURE SYSTEM BUILDS IN ACROSS THE SOUTHEAST. THIS WILL BRING A RETURN TO WARM AND HUMID AIR ACROSS THE NORTHEAST. TUESDAY...THE FRONT WILL BE OUT OF THE REGION AND WE WILL BE BETWEEN SYSTEMS. THE NEXT CHANCE OF SIGNIFICANT WEATHER WILL BE ON WEDNESDAY AS A STRONG COLD FRONT MOVES THROUGH THE REGION. THIS WILL BE OUR BEST CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS EASTERN NEW YORK AND WESTERN NEW ENGLAND. MODELS ARE SHOWING A DECENT AMOUNT OF QPF ASSOCIATED WITH THE FRONT. THURSDAY THROUGH NEXT WEEKEND...QUIET WEATHER PERIOD SETTING UP AS HIGH PRESSURE BUILDS INTO THE NORTHEAST. WILL KEEP THE GRIDS DRY AND TEMPERATURES A DEGREE OR TWO BELOW NORMAL. AVIATION...VFR CONDITIONS WILL CONTINUE THE NEXT 24 HOURS. KGFL MAY TEMPORARILY LOWER IN VISIBILITY WITH BR BETWEEN 0800Z AND 1200Z. HYDROLOGY...DRY WEATHER WILL CONTINUE THROUGH THE NEXT 24 HOURS. A WEAK FRONT WILL MOVE THROUGH THE AREA SUNDAY NIGHT AND MONDAY...BUT WILL NOT HAVE AN IMPACT ON RIVERS AND STREAMS AS QPF VALUES ARE FORECASTED TO BE LIGHT. NEXT CHANCE OF SIGNIFICANT RAIN WILL BE ON WEDNESDAY AS A STRONGER FRONT MOVES THROUGH THE REGION. BOTTOM LINE...NO HYDRO PROBLEMS ANTICIPATED IN THE SHORT TERM. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NY...NONE. VT...NONE. && $$ ny AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 300 PM CDT SAT JUL 23 2005 ...MAIN FORECAST CHALLENGE CONCERNS CONVECTION POTENTIAL THIS AFTERNOON AND EVENING... .SHORT TERM (TONIGHT-TUES)... WILL KEEP DISCUSSION SHORT WITH IMPENDING CHANCE OF SEVERE WEATHER THIS AFTERNOON. EXPECT COLD FRONT TO SWEEP SOUTHEAST ACROSS THE REGION THIS AFTERNOON AND EVENING WITH INCREASING THREAT FOR SOME SCATTERED THUNDERSTORMS ALONG AND AHEAD OF FRONT. MID-LEVEL CAP VERY STRONG I.E ESPECIALLY ACROSS THE SOUTH WITH CONVECTION THAT FIRED ACROSS CENTRAL NORTH DAKOTA EARLIER THIS AFTERNOON HAVING A TOUGH TIME SUSTAINING ITSELF AS IT ENCOUNTERS STRONG CAP FURTHER EAST. 18Z RUC MODEL SUPPORTS CURRENT CAP SHOWING 700MB TEMPS +12- +14C ACROSS CWFA THROUGH 00Z WITH A SLOW EROSION THEREAFTER. DEGREE /AREAL COVERAGE WILL BE HIGHLY DEPENDENT ON HOW FAST CAP ERODES. AT THIS POINT IT APPEARS NORTHERN PORTION OF CWFA AT GREATEST RISK FOR THUNDER AFTER 00Z. ELSEWHERE CAP MIGHT HOLD ITS GROUND DURING FROPA PASSAGE LATER THIS EVENING. BASED ON TIMING OF FRONT WILL END CONVECTIVE THREAT ACROSS EASTERN MOST COUNTIES BEFORE 06Z. IN WAKE OF FRONT DRIER/LESS HUMID DAY ON TAP FOR SUNDAY AS HIGH PRESSURE BUILDS INTO REGION. PRECIPITATION CHANCES RETURN ON MONDAY. AT CURRENT TIME EVENT LOOKS TO BE MORE OF A STRATIFORM RAIN SCENARIO WITH ISOLATED THUNDER CHANCES PER EXAMINATION OF SURFACE/ELEVATED BASED INSTABILITY PARAMETERS. WENT DRY ROUTE ON TUESDAY AND THUS DISREGARDED WET NAM SOLUTION AND WENT WITH MORE OPTIMISTIC GFS. .LONG TERM (WED-SAT)... LONGWAVE PATTERN REMAINS FAIRLY ZONAL ACROSS SOUTHERN CANADA/NORTHERN US WITH A SUGGESTION OF RIDGE BUILDING OVER THE HIGH PLAINS BY DAY 7. NORTHWEST FLOW ALOFT BECOMES MORE WESTERLY BY THE END OF THE PERIOD. ENSEMBLE MEMBERS IS REASONABLY GOOD AGREEMENT THROUGH THE PERIOD. THE 00Z GFS IS SLOWER AND HAS HIGHER AMPLITUDE THAN MOST OF THE ENSEMBLE SET. 120 HOUR 12Z GFS IS SLOWER THAN THE 00Z RUN AND IS FASTER THAN THE ECMWF. SO WILL USE THE GFS AS THE COMPROMISE. && AVIATION... SHOWERS AND THUNDERSTORMS IN NORTH CENTRAL ND WILL DRIFT INTO NORTHEAST ND THIS AFTERNOON. THUNDERSTORMS EXPECTED LATER THIS EVENING WITH MVFR CEILINGS POSSIBLE. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ BERG/HOPPES nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 256 PM CDT SAT JUL 23 2005 .DISCUSSION... ISOLATED STRONG TO SEVERE THUNDERSTORMS HAVE QUICKLY DEVELOPED IN THE HIGHER TERRAIN AREAS ACROSS PORTIONS OF NORTHWEST ARKANSAS THIS AFTERNOON. LATEST RUC / WATER VAPOR IMAGERY INDICATING A WEAK WESTWARD MOVING UPPER LEVEL DISTURBANCE IS MOVING OVER CENTRAL OKLAHOMA AROUND THE MAIN UPPER HIGH. THIS...COMBINED WITH AFTERNOON HEATING HAS ALLOWED FOR BETTER COVERAGE OF SHOWER/THUNDERSTORM ACTIVITY COMPARED TO YESTERDAY. AN ISOLATED SEVERE THREAT WILL CONTINUE THROUGH THE REMAINDER OF THE AFTERNOON HOURS ACROSS ALL OF SOUTHEAST OKLAHOMA AND NORTHWEST ARKANSAS WITH DAMAGING DOWNBURST WINDS AND LARGE HAIL POSSIBLE. LATEST RADAR DATA INDICATING THAT A SIGNIFICANT AMOUNT OF HAIL IS LIKELY MAKING IT TO THE GROUND IN THE STRONGEST CELLS...HOWEVER HAVE ONLY RECEIVED A PENNY SIZE HAIL REPORT SO FAR. AS THE UPPER HIGH CONTINUES TO SHIFT SOUTHEAST OF THE AREA OVER THE NEXT COUPLE OF DAYS...SSW WINDS AT THE SURFACE WILL SLOWLY BEGIN TO INCREASE. ALTHOUGH IT WILL LIKELY NOT BE AS HOT AS THE LAST FEW DAYS...WILL STILL SEE HIGH TEMPERATURES AROUND 100 ACROSS NORTHEAST OKLAHOMA AND THE LOWER VALLEY AREAS OF WEST-CENTRAL ARKANSAS. THE HEAT ADVISORY HAS BEEN EXTENDED FOR TULSA COUNTY THROUGH SUNDAY AS LOW TEMPS TONIGHT IN THE METRO EXPECTED TO BE AROUND 80 WITH HEAT INDICES SUNDAY AFTERNOON AROUND 105. GFS STILL PUSHING COLD FRONT INTO NORTHEAST OKLAHOMA TUESDAY NIGHT INTO WEDNESDAY WITH AN INCREASING CHANCE FOR SHOWERS AND THUNDERSTORMS ALONG THE BOUNDARY. WILL LIKELY ALSO SEE A BREAK FROM THE HEAT BEHIND COLD FRONT INTO THURSDAY AS CLOUDS/ELEVATED SHOWERS/THUNDERSTORMS REMAIN POSSIBLE AS UPPER SHORT-WAVE DIVES SOUTHEAST INTO REGION. && .PRELIMINARY POINT TEMPS/POPS... TUL 80 101 79 101 / 20 10 10 10 FSM 76 102 76 101 / 20 10 10 10 MLC 74 99 75 98 / 20 10 10 10 BVO 73 101 73 101 / 10 10 10 10 FYV 72 98 72 97 / 20 10 10 10 BYV 74 98 74 95 / 20 10 10 10 MKO 75 100 75 100 / 20 10 10 10 MIO 74 100 74 100 / 10 10 10 10 F10 75 100 75 99 / 20 10 10 10 HHW 73 99 74 99 / 20 10 10 10 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...HEAT ADVISORY UNTIL 7 PM SUNDAY FOR OKZ060. AR...NONE. && $$ SHORT TERM FORECASTER ID= 21 LONG TERM FORECASTER ID= 12 ok AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CHICAGO/ROMEOVILLE IL 300 AM CDT SUN JUL 24 2005 .DISCUSSION... THE SURFACE MAP SHOWS DEWPOINTS IN THE LOWER 70S ACROSS ALL OF NORTHEAST ILLINOIS...NORTH CENTRAL ILLINOIS AND NORTHWEST INDIANA THIS MORNING. MOST OF THE CLOUD COVER AND PRECIPITATION IS WELL NORTH. SO WE EXPECT A MOSTLY CLEAR TO PARTLY CLOUDY SKY. THE 850 MB ANALYSIS AT 00 UTC SHOWS WARM AIR ADVECTION AND SOUNDINGS WEST OF HERE SHOW LITTLE OR NO AFTERNOON INVERSIONS. THE HIGH TEMPERATURE IS EXPECTED TO BE 100 TO 103. WITH THE HIGH DEWPOINT WE EXPECT HEAT INDICIES...HI... OF 110 TO 115. WILL UPGRADE THE HEAT ADVISORY TO A EXCESSIVE HEAT WARNING FOR THE SOUTHERN COUNTIES OF OUR FORECAST AREA. WE FORECAST 115 HI FOR THREE HOURS THERE. CHICAGO AND COOK COUNTY WILL REMAIN IN AN EXCESSIVE HEAT WARNING. THE REST OF THE FORECAST AREA WILL EXPERIENCE HI OF 114 OR LESS AND WILL REMAIN IN AN ADVISORY TODAY. THUNDERSTORMS ARE WELL NORTH OF THE FORECAST AREA IN WISCONSIN AND NORTHERN MICHIGAN. THE UPPER LEVEL CLOUDS ARE EXPECTED TO MOVE EAST AND SOUTHEAST WITH THE WEST AND NORTHWEST WIND AT 250 MB SEEN ON THE PROFILER AND RUC40 WIND DATA AT 08 UTC. THE GFS MODEL BRINGS A 500 MB TROUGH INTO NORTHWEST MINNESOTA AND WESTERN ONTARIO BY 00 UTC WEDNESDAY. A SMALLER TROUGH MOVES INTO WESTERN WISCONSIN BY 00 UTC WEDNESDAY. SURFACE POTENTIAL TEMPERATURE AND PRESSURE FIELDS FORECASTS SHOW A FRONT OVER NORTHERN ILLINOIS BY TUESDAY. WILL KEEP THE SHOWERS AND THUNDERSTORMS FORECAST LATE MONDAY NIGHT THROUGH TUESDAY NIGHT. THEN THE AIR WILL BE COOLER FOR THE REST OF THE WEEK. && .AVIATION FORECAST FOR 00Z TAFS... RAIN AND TSTMS HAVE WEAKENED AND SLID OFF TO THE EAST OF TERMINALS THIS EVENING. HOWEVER HUGH OUTFLOW FROM THE NORTH OF THE COMPLEX WHEN IT WAS STRONG HAS BLOWN THRU NRN IL/NWRN IN AND SWITCHED WINDS TO NORTH. BUT WITH HIGH PRESSURE OFF TO OUR EAST...PRIMARY FLOW IS SOUTH WINDS AND SHUD BE WORKING AROUND TO SUCH AT OR SHORTLY AFTER 00Z. SKY WILL BE VFR WITH SOME SCT TO BKN AC AND OVC CI THIS EVENING... BREAKING OUT TO SCT BY MRNG. WITH HIGH PRESSURE PULLING FURTHER EAST SUNDAY...WINDS VEER MORE TO SW AS LOW PRESSURE TROF IN NRN PLAINS BUILDS INTO UPR MS VLY. GRADIENT ALSO TIGHENS ENUF TO FORCE WINDS TO 25-30 KTS IN MID TO LT MRNG THRU EARLY AFTN. WITH LOW PASSING ACROSS NRN LK MICHIGAN SUNDAY...WINDS BEGIN TO VEER MORE TO WEST WHILE LOOSENING PRESSURE GRADIENT AND WINDS THUS DYING OFF TO 10-12 KTS BY MID TO LT AFTN. MAYBE SOME AFTN CU ARND 4K BUT LITTLE ELSE. WINDS SHUD BE STRONG ENUF NEXT 24 HRS TO PROHIBIT FOG. && .WATCHES/WARNINGS/ADVISORIES... .IL COOK COUNTY...EXCESSIVE HEAT WARNING IN EFFECT FROM 7 AM SUNDAY TO 1 AM MONDAY .IL LASALLE GRUNDY LIVINGSTON FORD AND IROQUOIS COUNTIES...EXCESSIVE HEAT WARNING IN EFFECT FROM 7 AM SUNDAY TO 1 AM MONDAY. .IL REMAINDER...HEAT ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM MONDAY. .IN...BENTON...EXCESSIVE HEAT WARNING IN EFFECT FROM 7 AM SUNDAY TO 1 AM MONDAY. .IN REMAINDER...HEAT ADVISORY IN EFFECT FROM 7 AM SUNDAY TO 1 AM MONDAY. .LK MI...NONE $$ il AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 540 AM EDT SUN JUL 24 2005 .DISCUSSION... MAIN FCST CONCERNS ARE LINGERING TSRA THIS MORNING AND SHRA/TSRA POTENTIAL MON INTO MON NIGHT. DISCUSSION HAS BEEN DELAYED AND WILL BE BRIEF DUE TO ONGOING SEVERE WEATHER EPISODE. WV IMAGERY AND RUC ANALYSIS INDICATED A PROMINENT MID/UPPER LEVEL RDG OVER THE CNTRL CONUS. AT THE SFC...LOW PRES WAS LOCATED OVER E CNTRL MN WITH A WARM FRONT ESE TOWARD SW LWR MI AND A COLD FRONT SW INTO CNTRL NEB. A LINEAR MCS DEVELOPED OVER NW WI ON THE PERIPHERY OF THE RDG AND STRONG CAP OVER MN/WI AND NOSE OF WSW 40-50 KT LLJ...PER 00Z KMPX SNDG AND RADARS/PROFILERS...AND SPREAD THROUGH MUCH OF UPPER MI AND NRN WI. HEAVY RAIN HAS BEEN CONCENTRATED FROM NEAR KASX ESE TO NEAR KIMT WITH RADAR RAINFALL ESTIMATES INTO THE 3-4 INCH RANGE OVER FAR SW UPR MI. TODAY...RADAR/SATELLITE TRENDS AND MDLS FCST OF VEERING LLJ SUGGEST HEAVIER CONVECTION WITH THE MCS SHOULD EXIT MOST OF THE CWA BY 12Z WITH RAINFALL ENDING OVER S AND E PORTIONS OF THE CWA BY 14Z. AFTER THE REMNANTS OF THE MCS MOVE OUT OF UPPER MICHIGAN THIS MORNING...CLOUDS WILL EVENTUALLY DECREASE LEAVING PARTLY TO MOSTLY SUNNY SKIES BY THIS AFTERNOON. HOWEVER...11-3.9 IR IMAGERY AND SFC OBS INDICATED EXTENSIVE LOW CLOUDS OVER CNTRL INTO NE MN NORTH OF THE FRONTAL BOUNDARY. SO...CLEARING TREND WILL BE DELAYED TILL DRY ADVECTION TAKES OVER IN THE WAKE OF THE SFC TROF BTWN 15Z-18Z AND DAYTIME MIXING HELPS TO DISSOLVE ANY LINGERING LOW CLOUDS. WITH 850 MB TEMPS FCST NEAR 20C...SUNSHINE AND BETTER MIXING SHOULD PUSH TEMPS AT LEAST TO THE 85-90F RANGE...ESPECIALLY FOR LOCATIONS FAVORED BY DOWNSLOPE NW FLOW. LOCATIONS OVER W UPR MI NEAR LAKE SUPERIOR AND E OF MARQUETTE CAN EXPECT COOLER READINGS IN THE 70S. MON INTO TUE...NAM/GFS SUGGEST THAT SFC FRONTAL BOUNDARY WILL END UP OVER NRN IA INTO NRN IL BY 12Z MON. STRONG ISENTROPIC LIFT TO INITIATE CONVECTION MON WILL BE AIDED BY STRONG UPR LEVEL DIV WITH RIGHT ENTRANCE OF 250 MB JET FROM NRN MN INTO ONTARIO. SINCE UPR MI WILL BE WELL NORTH OF THE SFC AND H8 FRONT...EXPECT MOST OF THE SHRA/TSRA TO REMAIN SOUTH OF THE CWA...IN LINE WITH THE GFS FCST. HOWEVEVER...GIVEN THE BROAD 300K-315K ISENTROPIC REGIME AND POTENTIAL FO SIGNFICANT 700-600 FRONTOGENESIS...CANNOT RULE OUT SOME ELEVATED SHRA/TSRA INTO THE AREA. SO...GOING CHANCE POPS STILL LOOK APPROPRIATE. MDLS SUGGEST BEST CHANCE WOULD BE FROM LATE AFTERNOON THROUGH 06Z TUE. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE EASTERN ND/GRAND FORKS ND 355 AM CDT SUN JUL 24 2005 .DISCUSSION AND SHORT TERM (TODAY)...SEVERAL SHORTWAVES PASSING BY ATTM. ONE IS CAUSING THE THUNDERSTORMS IN EASTERN SD AS IT PASSES SLIGHTLY NORTH OF THE LOW LEVEL FRONTAL BOUNDARY. WATER VAPOR LOOP AND PRESENCE OF THE STORMS SUGGESTS IT IS FARTHER WEST THAN RUC MODEL SHOWS...MORE LIKE GFS. EXPECT LINE OF STORMS TO SAG TOWARD SOUTHEAST AS THE SHORTWAVE PROGRESSES. A WEAKER SHORTWAVE GENERATING SCATTERED CLOUDS FROM FAR TO BDE AT 08Z HAS A 35 KNOT OR SO LOW LEVEL JET IMMEDIATELY FOLLOWING WHICH WILL SHALLOW THE HIGH MOISTURE AND DRY OUT THE SURFACE AS IT MIXES DOWN SOME THIS MORNING. DON/T THINK THE DECOUPLED JET WILL LOWER DEW POINTS SOON ENOUGH TO PREVENT PATCHY DENSE FOG EARLY THIS MORNING SOUTH THROUGH NORTHEAST FROM FARGO. STRONG SHORTWAVE CURRENTLY PASSING JUST NORTH OF THE U.S. BORDER IS USHERING IN THE DRIER AIR WHILE 500 MB VORTICITY WILL BE CHANNELED THIS MORNING AND OF LITTLE CONSEQUENCE. SO FOR TODAY... GENERALLY MOSTLY SUNNY NORTH AND PARTLY CLOUDY SOUTH AND LESS HUMID. MODEL SOUNDINGS SUPPORT 90F EXCEPT MID 80S NEAR CANADIAN BORDER. .TONIGHT-MON...NAM/UKMET AGREE ON SUBSTANTIAL UPPER JET DIVERGENCE TO AID SHOWERS/THUNDERSTORM DEVELOPMENT MAINLY AFTER MIDNIGHT AND MON MORNING. IT CORRELATES WITH RESPECTABLE CONVERGENT FLOW AT 925-850 MB EXCEPT THE WIND SPEEDS THOSE LEVELS ARE ONLY 10-20 KNOTS...NOT ENOUGH DURING THE LAST SEVERAL DAYS WITH SIMILAR CONDITIONS TO CAUSE SIGNIFICANT DEVELOPMENT ON ITS OWN. RETAINED CHANCE OF CONVECTION LARGELY AS IS MAINLY OUT OF RESPECT FOR THE JET DYNAMICS AND THE THERMAL GRADIENT ON THE WAY. NAM MOS ACTUALLY SHOWS POPS IN LIKELY OR BETTER CATEGORY FOR MON BUT CURRENTLY AM NOT AS CONVINCED AS THAT. NOT ENOUGH INSTABILITY TO FAVOR MORE THAN ISOLATED THUNDER. .TUE-SAT...COOLER CONDITIONS STILL EXPECTED AND LOWERED MOST TEMPERATURES 2-3 DEGREES. 850 MB TEMPERATURES TO HOVER A FEW DEGREES EITHER SIDE OF 10C TUE/WED WITH SOME WARMING THEREAFTER. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ GV nd AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 313 AM EDT SUN JUL 24 2005 .SYNOPSIS... HI PRESS TO BUILD ACRS ACRS THE FA FROM THE WEST TODAY...THEN OUT TO THE EAST OF THE FA TONITE. TROF (FOR LACK A BETTER TERM) TO MOVE ACRS THE GREAT LKS REGION TONITE...THEN ACRS THE FA ON MON. WK HI PRESS LOOKS TO AFFECT THE FA ON MON NITE. CF TO MOVE ACRS THE GREAT LKS REGION ON TUE. S/W TO MOVE ACRS THE FA ON TUE. .SHORT TERM (TODAY THROUGH TUESDAY)... 00-02Z RUC13 SHOWS TEMPS TO GET UP INTO THE 70S-M80S TODAY WITH WESTERLY SFC WINDS BECOMING MORE SOUTHERLY WITH TIME AT 5-15 KTS. T1MAX TEMPS ARE IN THE 80S TODAY. FEW TWEAKS TO FIRST PERIOD TEMPS/WINDS BASED ON THIS DATA AND MESONET OBS. SOME LOW-LVL MSTR TO AFFECT THE FA TODAY. RUC SHOWS NIL PCPN/CAPE ACRS THE FA TODAY WITH MOSUNNY SKIES OTRW. WK H85 WAA TO TAKE PLACE ACRS THE FA THROUGHOUT THE SHORT-TERM PERIOD. SOME LOW-LVL MSTR ADVECTION TO TAKE PLACE ACRS THE FA TODAY...TONITE...AND LATER ON TUE. LOW-LVL MSTR TO INCREASE ACRS THE FA TONITE AND EARLY ON MON...THEN AGAIN LATER ON TUE. LOW-LVL LAPSE RATES TO BE HI ACRS THE FA THIS AFTERNOON. SOME MID-LVL MSTR TO AFFECT THE FA TONITE AND ON TUE. PW VALUES ACRS THE FA LOOK TO BE 1-1.5" TONITE...AROUND AN INCH ON MON/MON NITE...THEN 1-2" ON TUE. 88D MOSAIC SHOWS THAT THE "ROUGE" +SHRA THAT MOVED ACRS PORTIONS OF THE FA FROM THE N-NW ARE GONE ATTM. NY STATE POLICE REPORT SOME FG PATCHES ATTM. WILL HANDLE ANY LINGERING FG ISSUES WITH THE STF. NEXT CHC FOR ANY CONVECTION STILL APPEARS TO BE BY LATER TONITE THRU AT LEAST THE FIRST PART OF MON...THEN AGAIN ON TUE AFTERNOON ACRS MUCH OF THE FA. THE GOING CHC POPS STILL LOOK GOOD FOR THESE PERIODS. WIND FIELDS ALOFT GRADUALLY INCREASE THROUGHOUT THE SHORT-TERM PERIOD...SO ANY CONVECTION BY LATER IN THE PERIOD COULD BE AT LEAST STRONG. T1MAX TEMPS ARE IN THE L80S-L90S ON MON. T1MIN TEMPS ARE MOSTLY IN THE 50S-L60S TONITE AND ON MON NITE. .LONG TERM (TUESDAY NIGHT THROUGH SATURDAY)... NO CHANGES TO THE GOING FCST FOR NOW. WRK ZONES AND PRELIM ISC GRIDS AVAILABLE. ALL FINAL PRODUCTS BY 4 AM. .AVIATION... IR SATELLITE TRENDS SHOW SCT-BKN070 SHOWING UP AT KBTV/KMPV SHOULD MOVE OUT OF THE AREA 06-08Z. RADIATION FOG FORECAST TO DEVELOP AT KSLK AND KMPV...WITH LIFR CONDITIONS 08-12Z. TEMPO OF IFR VIS AT KMSS AS WINDS GO LIGHT AND THERE IS THE POSSIBILITY OF BR FORMATION. CIG/VIS IMPROVING TO VFR 12-14Z...THEN VFR FOR THE REMAINDER OF THE PERIOD. .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS/SHORT TERM/LONG TERM...MURRAY AVIATION...HANSON vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HANFORD CA 920 AM PDT SUN JUL 24 2005 .SHORT TERM...FOR THE CENTRAL CALIFORNIA INTERIOR...SHORT TERM CONCERN REMAINS FLASH FLOOD POTENTIAL IN THE TULARE COUNTY MOUNTAINS AND KERN COUNTY MTNS/DESERTS. GOES SOUNDER DATA SHOW AXIS OF PRECIP WATER IN EXCESS OF ONE INCH EXTENDS WEST INTO THE KERN DESERT...WITH MSAS THETA-E VALUES APPROACHING 340K AND SFC MSTR CONVERGENCE AXIS EXTENDING N-S THRU DESERT ZONES. TULARE MTNS AND KERN MTN/DESERT ZONES REMAIN IN AREA THAT WILL EXPERIENCE BEST DIFFERENTIAL HEATING AND WITH WEAK FLOW ALOFT CELLS MAY REMAIN NEARLY STATIONARY...THUS FLASH FLOOD WATCH REMAINS WARRANTED FROM 1200-2100 PDT. PREFER SHORT TERM RUC GUIDANCE FOR MOISTURE PROGS THROUGH 00Z GIVEN COMPARISON WITH SATELLITE DATA...AND PROGGED SOUNDINGS FOR DESERT ZONES INDICATE SBCAPE EXCEEDING 2000 J/KG THIS AFTERNOON. PRIMARY CONVECTIVE THREAT APPEARS TO BE HEAVY RAINFALL AS INCREASE IN LOW LEVEL MOISTURE FROM SATURDAY/S PRECIP HAS LOWERED THE LFC TO AROUND 8000 FEET AND SHOULD DECREASE STRONGER DOWNBURST POTENTIAL. CURRENT GRID PACKAGE REMAINS IN SHAPE WITH NO UPDATES REQUIRED AT THIS TIME. .LONG TERM...TUESDAY NIGHT THROUGH SATURDAY...MEDIUM RANGE PROGS IN GOOD GENERAL AGREEMENT FOR THIS PERIOD...WITH THE PREVAILING FEATURES BEING A STRONG DRY UPPER RIDGE OVER THE SOUTHWESTERN CONUS AND A WEAK UPPER TROUGH NEAR 130W. AS THE RESULT OF INTERACTION BETWEEN THESE TWO FEATURES...THE UPPER FLOW OVER SOCAL BECOMES MORE SOUTH TO SOUTHEAST THURSDAY THROUGH SATURDAY WHICH MAY ALLOW FOR MONSOONAL MOISTURE TO RETURN TO THE CWFA...MAINLY NEAR THE CREST OF THE SOUTHERN SIERRA NEVADA. SINCE THIS MOISTURE WILL BE HIGH BASED...ANY CONVECTIVE ACTIVITY SHOULD BE CONFINED TO THE SOUTHERN SIERRA NEVADA AND BE ISOLATED IN COVERAGE AND CONFINED TO THE AFTERNOON AND EARLY EVENING. SINCE CONFIDENCE FOR THIS PERIOD IS IMPROVED...WILL STAY CLOSE TO MEX GUIDANCE AND KEEP TEMPERATURES A BIT ABOVE NORMAL THROUGH THE PERIOD. && .AVIATION...VFR CONDITIONS WILL PERSIST FOR ALL AREAS THROUGH 18Z MONDAY. REFER TO TAFS AT KMCE...KFAT...AND KBFL FOR DETAILS. && .HNX...WATCHES/WARNINGS/ADVISORIES...FLASH FLOOD WATCH FROM NOON UNTIL 900 PM PDT THIS EVENING FOR THE KERN COUNTY MOUNTAINS/DESERTS AND THE TULARE COUNTY MOUNTAINS. && $$ WWW.WEATHER.GOV/HANFORD /USE ALL LOWER CASE/ JSN/DS ca AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE PADUCAH KY 534 AM CDT SUN JUL 24 2005 .DISCUSSION... IN THE MIDST OF AN EXCESSIVE HEAT WARNING...HOURLY AND MAX/MIN TEMPERATURES...AS WELL AS DEWPOINTS...HAVE PROVED TO BE PROBLEMATIC WITH RESPECT TO PEAK HEAT INDEX READINGS EACH AFTERNOON AND EVENING. ANTECEDENT MOISTURE TRAPPED IN THE SUBSIDENCE INVERSION HELPED TO GENERATE EARLY AM FOG BOTH THIS MORNING AND SATURDAY MORNING...RETARDING THE RAPID SURFACE HEATING BY 1-2 HOURS. IN ADDITION...HIGHER THAN EXPECTED HIGHER THETA-E AIR MOVED ACROSS THE PAH FORECAST AREA...PROVIDING AN ENVIRONMENT FOR CU DEVELOPMENT DURING THE AFTERNOON. THE CHANGE IN THE ENERGY BUDGET NEEDED TO DEVELOP THE CLOUD COVER HELPED TO LIMIT THE EXPENDITURE TOWARD INCREASING MAX TEMPERATURES ON SATURDAY. THE NAM AND GFS MOS TEMPERATURE FORECASTS HAVE BEEN 2-5 DEGREES TOO WARM DURING THE PAST 48 HOURS FOR BOTH THE MAX AND MIN TEMPERATURES. WITH SOME LOW LEVEL MOISTURE STILL IN PLACE...I HAD TO CONSIDER A MORE CONSERVATIVE TEMPERATURE APPROACH TODAY...WITH THE WARMEST TEMPERATURES LIMITED TO SOUTHWEST ILLINOIS. IN THE GRAPHICAL AND TABULAR FORECASTS TODAY...ADDED VARIABILITY IN CLOUD COVER BETWEEN MOSTLY SUNNY AND PARTLY CLOUDY. ALTHOUGH BELOW THE THRESHOLD FOR THE MENTION OF WEATHER...A SUBTLE INCREASE IN PRECIPITATION CHANCES WAS MADE OVER SOUTHEAST IL/SOUTHWEST IN THIS AFTERNOON. IF ENOUGH INSTABILITY/MOISTURE POOLS IN THIS AREA DURING THE AFTERNOON...I CANNOT RULE OUT AN ISOLATED THUNDERSTORM. THE GFS/MAV/ MOS DEWPOINTS INITIALIZED WELL WITH SURFACE OBSERVATIONS...SO BLENDED THE 80KM RUC AND GFS MOS DEWPOINTS THROUGH TUESDAY...ADJUSTING DOWNWARD FOR A SLIGHT HIGH MODEL BIAS /1-2 DEGREES/ IN MODEL DEWPOINTS. AT THIS TIME...I AM RELUCANT TO PUSH BEYOND CURRENT EXPIRATION OF EXCESSIVE HEAT WARNING FOR THE PAH FORECAST AREA. INCREASING CLOUDS...AND THE POTENTIAL FOR WIDELY SCATTERED TO SCATTERED AFTERNOON AND EVENING CONVECTION TUESDAY AFTERNOON THROUGH WEDNESDAY SHOULD LESSEN THE NEED FOR FURTHER HEAT ADVISORIES/WARNINGS. GFS GUIDANCE CONTINUES TO FLATTEN AND SHEAR OUT THE PROGRESSIVE SHORTWAVE ON WEDNESDAY...SUGGESTING A SLOWER ONSET OF SHOWERS AND THUNDERSTORMS. I HAVE LOWERED THE POP FORECAST FOR TUESDAY AFTERNOON AND EVENING...BUT INCREASING POPS A LITTLE HIGHER ON WEDNESDAY. LITTLE...IF ANY CHANGE WAS MADE TO THE REMAINDER OF THE FORECAST. && .PAH WATCHES/WARNINGS/ADVISORIES... .KY...EXCESSIVE HEAT WARNING UNTIL 6 PM MONDAY FOR KYZ001...KYZ002...KYZ003...KYZ004...KYZ005...KYZ006... KYZ007...KYZ008...KYZ009...KYZ010...KYZ011...KYZ012... KYZ013...KYZ014...KYZ015...KYZ016...KYZ017...KYZ018... KYZ019...KYZ020...KYZ021...KYZ022. .MO...EXCESSIVE HEAT WARNING UNTIL 6 PM MONDAY FOR MOZ076...MOZ086...MOZ087...MOZ100...MOZ107...MOZ108... MOZ109...MOZ110...MOZ111...MOZ112...MOZ114. .IL...EXCESSIVE HEAT WARNING UNTIL 6 PM MONDAY FOR ILZ075...ILZ076...ILZ077...ILZ078...ILZ080...ILZ081... ILZ082...ILZ083...ILZ084...ILZ085...ILZ086...ILZ087... ILZ088...ILZ089...ILZ090...ILZ091...ILZ092...ILZ093... ILZ094. .IN...EXCESSIVE HEAT WARNING UNTIL 6 PM MONDAY FOR INZ081...INZ082...INZ085...INZ086...INZ087...INZ088. && $$ SMITH ky AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1135 AM EDT SUN JUL 24 2005 .UPDATE... CLUSTER OF STORMS CONTINUES TO PROGRESS ACROSS SOUTHEAST MICHIGAN. COVERAGE HAS DIMINISHED...ESPECIALLY ON THE SOUTHWEST FLANK OF THE STORMS...GIVEN A STRONGER CAP IN PLACE. ADDITIONAL STORMS CONTINUE TO PERCOLATE FROM NORTHERN LOWER THROUGH LAKE HURON ALONG THE LEAD EDGE OF THE 700MB THETA-E RIDGE INDICATED BY THE 12Z RUC. AT THIS POINT NO ACTIVITY IS OCCURRING TO THE SOUTHWEST...UNDER MORE CAPPED ATMOSPHERE WITH 850MB TEMPS >22C/700MB TEMPS>12C. QUESTION REMAINS WHETHER WE WILL BE ABLE TO BREAK THROUGH THIS CAP AS THE COLD FRONT SWINGS IN FROM WISCONSIN. 12Z NAM/RUC BOTH SHOW CONVECTION DEVELOPING LATE THIS AFTERNOON...WHILE 06Z GFS/00Z WRF-XX BOTH KEEP IT DRY. WATER VAPOR LOOP SHOWS A SHORTWAVE/CONVECTIVE VORT OVER THE NORTHERN PLAINS...LEADING TO SOME STORMS THERE WELL UPSTREAM. SUBTLE SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES...LEADING TO SOME SUBSIDENCE THAT COULD FURTHER INHIBIT CONVECTION OVER THE CENTRAL GREAT LAKES. 00Z NCAR 4KM WRF /WHICH DID HOLD ONTO THE MORNING CONVECTION FOR TOO LONG/ DID DEVELOPS STORMS ACROSS THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY THIS AFTERNOON/EVENING IN THE VICINITY OF THE UPPER WAVE...BUT STRUGGLES FARTHER EAST UNDER THE UPPER RIDGE. FEELING IS THAT WE WILL REMAIN DRY ONCE THE CURRENT ONGOING ACTIVITY MOVES OUT. HOWEVER GIVEN THE CONTINUED POTENTIAL FOR SEVERE WEATHER /850MB WINDS 35-40KTS...NEARLY UNIDIRECTIONAL FLOW...DRY MID-LEVEL AIR...AND IMPRESSIVE CAPE BUILDING UNDER THE CAP/ AND A COUPLE DIFFERENT MODELS INDICATING THE CAP BREAKING... WILL ADD A LOW CHANCE POP FOR THIS AFTERNOON/EVENING. CONSEQUENTLY WILL CONTINUE THE MENTION OF POSSIBLE SEVERE WEATHER IN THE HWO. OTHER QUESTION WAS WITH TEMPERATURES AND HEAT INDICES. VIS SATELLITE SHOWS CLOUD SHIELD THINNING ACROSS SOUTHWEST LOWER...WHERE AN INCREASING SOUTHWESTERLY FLOW HAS ALSO PICKED UP. HEAT INDICES ARE ALREADY BREAKING 100F ACROSS ILLINOIS AS OF 15Z. HOWEVER...STILL DO NOT EXPECT SOUTHEAST MICHIGAN WILL WARM UP ENOUGH TO REACH HEAT ADVISORY CRITERIA. REST OF THE CURRENT FORECAST LOOKS ON TRACK. && .AVIATION...705 AM EDT SUN JUL 24 2005 RAIN/EMBEDDED THUNDERSTORMS CAN BE EXPECTED THE FIRST SEVERAL HOURS OF THE FORECAST...WITH CEILINGS OF 1500 FT OR LOWER. WILL ADD A GUST IN FNT AS LINE SEGMENTS ATTEMPTS TO TRANSLATE INTO THE GENESEE. MUCH OF THE WIND HAS REMAINED ELEVATED...WITH ASOS/AWOS GUSTS ONLY IN THE 20-40 KNOT RANGE. WILL TENTATIVELY END THIS ACTIVITY AROUND NOON AS WARM FRONT PUSHES TO THE EAST AND ELEVATED ACTIVITY GOES WITH IT. ANTICIPATE CAPPING TO BE TOO STRONG FOR SURFACE BASED CONVECTION ALONG OUTFLOW THAT IS LEFT BY THIS CURRENT ACTIVITY...ALTHOUGH WILL HAVE TO RE-EVALUATE THIS MID MORNING AS INITIAL ACTIVITY IS ON THE WANE. LIGHT SOUTHWEST WINDS THIS EVENING TURNING TO THE NORTHWEST AND THEN NORTH AFTER MIDNIGHT. WILL ADD SOME MINOR FOG GIVEN ABUNDANT LOW LEVEL MOISTURE THAT WILL BE AROUND FROM BOTH RAINFALL AND ADVECTION OF 70-75F DEWPOINTS FROM THE MIDWEST. && .SHORT TERM...TODAY AND TONIGHT...ISSUED AT 335 AM EDT GOOD AGREEMENT ON BRINGING ACTIVE WARM FRONT INTO LOWER MICHIGAN THIS MORNING...WITH SCATTERED SHOWERS/THUNDERSTORMS BEING REPLACED BY A RATHER POTENT MCS SLIDING SOUTHEAST AROUND UPPER RIDGE. WILL UP THUNDERSTORM CHANCES TO 80-90% FOR MUCH OF CWA THIS MORNING AND TAPER TO ABOUT 60% FAR SOUTHWEST COUNTIES. THIS ACTIVITY WILL MAKE TEMPERATURE FORECASTING VERY DIFFICULT TODAY AS CLOUD COVER/PRECIPITATION KEEP TEMPERATURES DOWN THROUGH THE MORNING AND LEFTOVER OUTFLOW MONKEYS WITH SOUTHWEST FLOW THAT IS EXPECTED TO DEVELOP IN THE WAKE OF THE PASSING WARM FRONT. WILL EDGE TEMPERATURES DOWN SEVERAL DEGREES BASED ON TRENDS IN THE 00Z MODEL RUNS. THIS ADJUSTMENT WILL BRING ALL AREAS BELOW HEAT ADVISORY CRITERIA WITH HEAT INDICES INTO THE 95-100 DEGREE RANGE ACROSS THE SOUTHWEST CWA THIS AFTERNOON. THIS WILL HAVE TO BE RE-EVALUATED BASED ON WHAT HAPPENS WITH THE THUNDERSTORMS OVER THE NEXT 6-9 HOURS. AT THIS TIME IT APPEARS THAT THE NAM/S MORE SOUTHERN EXTENT OF THUNDERSTORMS IS WORKING OUT...WHICH LENDS SUPPORT FOR A "LESS HOT" FORECAST. THAT SAID...CONDITIONS WON/T BE PLEASANT AS LOWER/MID 70 DEWPOINTS BRING HUMIDITY LEVELS UP DRAMATICALLY AS COMPARED TO THE PAST FEW DAYS. GIVEN THIS AIRMASS...WILL UP LOW TEMPERATURES A DEGREE OR TWO FOR TONIGHT...WHICH IS SUPPORTED BY GUIDANCE...ESPECIALLY ACROSS THE SOUTHERN CWA WHERE FRONT WILL BE STALLING AND LOW LEVEL MOISTURE POOLING. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED AT 335 AM EDT AS TO BE EXPECTED...MESOSCALE FEATURES AND SHORT WAVE INITIALIZATIONS HAVE RESULTED IN A SHIFT IN THE GOING FORECAST. THIS UPCOMING FIRST HALF OF THE WEEK WILL BE IMPACTED BY A FEW SYNOPTIC BOUNDARIES AND A COUPLE OF MCS/S...SEVERE POTENTIAL LOOMING AND HEAVY RAINFALL PRODUCERS. THIS AFOREMENTIONED FRONTAL BOUNDARY WILL BE WAVERING ACROSS THE GREAT LAKES REGION AS EVENTUAL TRACK OF ONGOING MCS WILL DICTATE JUST HOW FAR SOUTH THE BOUNDARY GETS ON MONDAY. STILL EXPECT THE BOUNDARY TO REMAIN CLOSE ENOUGH TO THE SOUTHERN COUNTIES TO WARRANT OUR CONTINUED CHANCE FOR CONVECTION. UPSTREAM CAPES (IE OVER INDIANA AND OHIO) ARE PROGGED TO BE BETWEEN 3000-4000 J/KG AND WITH INCREASING LOW LEVEL JET...POTENTIAL FOR SOME OF THESE CELLS TO CROSS OVER THE WARM FRONT WHICH COULD PROVE TO BE INTERESTING... FURTHER UPSTREAM, AS ANOTHER WAVE INTERACTS WITH THE INSTABILITY, WE SHOULD SEE ANOTHER MCS EVOLVE AND TRACK TOWARD THE LOCAL AREA MONDAY NIGHT. PWATS FROM THE VARIOUS NUMERICAL MODELS STILL HOLD ONTO THE 2" (EVEN HIGHER) WITH K-INDICES TOUCHING 40. SO HEAVY RAINFALL POTENTIAL REMAINS AN ADDITIONAL CONCERN. THIS SYSTEM TRACKS ACROSS THE AREA ON TUESDAY AND LEAVING US UNDER CLOUDY SKIES, HIGH MOISTURE CONTENT AND ADDITIONAL CONVECTION DEVELOPING. CONFIDENCE IN EITHER NUMERICAL MODEL IS QUITE LOW, NEVERTHELESS, THEY ALL SUGGEST THIS FRONTAL BOUNDARY WILL WAIVER AS THE LOW LEVEL JET UPSTREAM WILL LIKELY DEVELOP ANOTHER MCS TOWARD TUESDAY NIGHT AS ONE LAST SHORT WAVE COMES DOWN INTO THE WESTERLIES. MODEL TRENDS HAVE POINTED TO MUCH LESS AMPLIFICATION FOR WEDNESDAY WHICH LEAVES OPEN THE POSSIBILITY FOR ADDITIONAL CONVECTION (PERHAPS THE MCS) INTO WEDNESDAY MORNING. AFTER COLLABORATING WITH SURROUNDING OFFICES, HAVE DECIDED TO ADD THAT TO THE GRIDS AND LOWER TEMPS WITH COOL ADVECTION UNDERWAY BY AFTERNOON. SORRY FOR THE BREVITY AS WE ARE CLOSELY MONITORING UPSTREAM ACTIVITY THIS SUNDAY MORNING. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...SEVERE THUNDERSTORM WATCH #670... MIZ055-060>063-068>070-075>076-082>083...UNTIL 2 PM. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON...7 AM SUNDAY TO 5 PM SUNDAY. SEVERE THUNDERSTORM WATCH #670...NEARSHORE AND OPEN LAKE WATERS FROM PORT AUSTIN TO PORT HURON...UNTIL 2 PM. LAKE ST CLAIR...SEVERE THUNDERSTORM WATCH #670 UNTIL 2 PM. MI WATERS OF LAKE ERIE...SEVERE THUNDERSTORM WATCH #670 UNTIL 2 PM. && $$ UPDATE.......BRAVENDER AVIATION.....DG SHORT TERM...DG LONG TERM....BGM HTTP://WEATHER.GOV/DETROIT (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BILLINGS MT 924 AM MDT SUN JUL 24 2005 .SHORT TERM...VALID FOR TDY AND MON... ONLY MINOR CHANGES TO THE FORECAST THIS MORNING. MOSTLY CLEAR SKIES ACROSS THE AREA...WITH DEWPTS RUNNING SEVERAL DEGREES LOWER THAN YESTERDAY AT THIS TIME...AS SFC BOUNDARY IS NOW DRAPED W TO E JUST TO OUR SOUTH. THOUGH WE ARE WITHIN A STABLE AIRMASS...MUCH MORE UNSTABLE AIR EXISTS ALONG AND SOUTH OF THE SFC BOUNDARY. BEST CHANCE OF ANY CONVECTION THIS AFTN SHOULD BE IN OUR FAR SOUTHEAST AS THIS BOUNDARY BEGINS TO LIFT NORTHWARD IN RESPONSE TO APPROACHING SHORTWAVE. RUC/NAM SHOW INCREASING H7 THETA-E ADVECTION LATER TODAY...AND WITH CONVERGENCE NEAR SFC BOUNDARY WILL SUSTAIN ISOLD/SCT POPS. HIGHER LOW LEVEL SHEAR IN PROXIMITY TO BOUNDARY...ALONG WITH SUFFICIENT CAPE...WARRANTS A CONTINUED MENTION OF POSSIBLE SEVERE INTO THE EVNG. OUT WEST...BELIEVE BEST CHANCE OF CONVECTION (THOUGH WITH MUCH LOWER CAPE VALUES) WILL BE THIS EVENING WITH A FROPA AND INCRG UPPER DIVERGENCE IN RRQ OF 80KT JET TO OUR NORTH...BUT WILL HOLD ON TO ISOLD MENTION LATE (AFTER 21Z) TODAY. REGARDING TEMPS...A E TO NELY FLOW WILL KEEP TEMPS FROM GOING TOO FAR...BUT STILL SHOULD SEE HIGHS INTO THE 90S WITH WARM AMS STILL IN PLACE AND DECENT MIXING/PLENTY SUN. GRIDS ALREADY TWEAKED. MINOR ZONE UPDATE COMING SHORTLY. JKL .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... TUESDAY WILL STILL BE UNSEASONABLY COOL AS THE SURFACE HIGH PRESSURE CELL WILL BE RESIDENT OVER SOUTHEAST MONTANA WITH UPSLOPE CLOUDS AND PRECIP LINGERING LIMITING INSOLATION. SHORTWAVE ENERGY THAT IS PROGGED TO BRING A GOOD SHOT OF PRECIP MONDAY NIGHT STILL WILL BE FORCING SHOWER ACTIVITY OVER SOUTHEAST MONTANA TUESDAY MORNING. ETA AND GFS BOTH HAVE THIS ACTIVITY LASTING INTO THE TUESDAY MORNING OVER SOUTHEAST MONTANA AND THIS IS REFLECTED IN THE FORECAST. DRYING FOR WEDNESDAY WITH SOLAR INSOLATION RETURNING WITH AS HEIGHTS BUILD ALOFT AND THIS TREND CONTINUES INTO THURSDAY WITH MODELS DIVERGING ON HOW STRONG THE RIDGE WILL BE FOR FRIDAY. GFS HAS A SHORTWAVE SUPRESSING THE RIDGE A BIT ON FRIDAY WITH IT REBOUNDING FOR SATURDAY...WHICH THE 18Z GFS IS IN AGREEMENT WITH. SLIGHTLY ABOVE NORMAL TEMPS LOOKS GOOD IN THE EXTENDED WITH A MOSTLY DRY FORECAST. MONSOONAL MOISTURE LOOKS TO REMAIN SOUTH OF THE AREA FOR THE PERIOD. BORSUM && .AVIATION... MOSTLY CLEAR SKIES EARLY WILL GIVE WAY TO SOME CUMULUS DEVELOPMENT AFTER 18Z. AFTER 21Z...ISOLATED THUNDERSTORMS EXPECTED IN THE FAR WEST...SOUTH AND SOUTHEAST...WITH STRONGER STORMS OVER SOUTHEAST MONTANA. VFR CONDITIONS WILL PREVAIL TODAY. LOCAL MVFR WITH INCRG CHANCES OF CONVECTION ALL ROUTES TONIGHT. JKL && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 092 059/073 052/076 053/088 060/093 061/094 061/093 1/U 33/T 30/U 00/U 00/U 01/U 11/U LVM 090 050/072 047/076 048/085 052/089 053/090 053/089 2/T 33/T 20/U 00/U 01/U 12/T 22/T HDN 093 058/073 054/079 054/091 058/095 060/096 059/096 1/U 33/T 30/U 00/U 00/U 00/U 00/U MLS 094 061/076 055/077 056/089 061/093 063/094 062/094 0/U 32/T 30/U 00/U 00/U 00/U 00/U 4BQ 094 062/074 056/078 056/087 060/092 061/094 061/094 2/T 33/T 32/T 00/U 00/U 00/U 00/U BHK 091 061/072 054/075 053/085 056/088 058/089 059/093 1/U 33/T 20/U 00/U 00/U 00/U 00/U SHR 095 057/075 054/077 051/089 055/094 056/095 056/094 3/T 33/T 32/T 00/U 00/U 01/U 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS mt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1013 AM EDT SAT JUL 23 2005 .SHORT TERM (THIS AFTERNOON)... A LARGE UPPER LEVEL RIDGE OF HIGH PRESSURE IS CENTERED ACROSS THE MISSISSIPPI VALLEY THIS MORNING. SATELLITE IMAGERY SHOWS SOME MID AND HIGH LEVEL CLOUDS MOVING AROUND THE EASTERN PERIPHERY OF THE RIDGE...AND THESE COULD SPREAD ACROSS THE AREA THIS AFTERNOON. IN ADDITION...SOME RATHER FLAT CUMULUS MAY DEVELOP WITH THE HEATING OF THE DAY. BECAUSE OF THIS...WILL INCREASE THE FORECAST SKY COVER TO PARTLY CLOUDY. THE REMAINDER OF THE FORECAST IS IN EXCELLENT SHAPE...AND FEW IF ANY CHANGES ARE REQUIRED. MORNING SOUNDINGS AS WELL AS MODEL SOUNDINGS FOR THIS AFTERNOON ALL INDICATE SOME MID-LEVEL CAPPING WHICH SHOULD SUPPRESS ANY CONVECTIVE DEVELOPMENT THIS AFTERNOON...THUS THE FORECAST WILL REMAIN DRY. HIGH TEMPERATURES WILL BE HELD CLOSE TO CLIMATOLOGICAL VALUES NEAR THE COAST THIS AFTERNOON DUE TO THE ONSHORE FLOW...BUT INLAND AREAS COULD REACH THE MID 90S. DEWPOINTS SHOULD BE LOW ENOUGH TO KEEP HEAT INDEX VALUES BELOW 100 TODAY. && .AVIATION... ONCE WE CAN CLEAR THE HAZE OUT OF FLO...EXPECTED TO OCCUR BY 16Z...EXPECT TO SEE VFR CONDITIONS FOR THE BALANCE OF THE AFTERNOON WITH NE-E WINDS RUNNING 5 TO 10 KT. && .MARINE... GOING COASTAL WATERS FORECAST LOOKS TO BE IN FINE SHAPE WITH NE WINDS IN THE 10 TO 15 KT RANGE AND SEAS RUNNING 3 TO 4 FT. ONLY CHANGE COMING WILL BE TWEAKING THE TIMING OF THE SHIFT TO THE EAST TO LATE IN THE DAY AS THE LATEST RUC GUIDANCE INDICATES THE SHIFT TO THE EAST WILL OCCUR BETWEEN 21Z AND 00Z. && .ILM WATCHES/WARNINGS/ADVISORIES... NC...NONE. SC...NONE. MARINE...NONE. && $$ SHORT TERM...JAQ AVIATION...RAN MARINE...RAN nc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GREENVILLE-SPARTANBURG SC 1116 AM EDT SUN JUL 24 2005 .SHORT TERM (REST OF TODAY)... W/V AND VISIBLE SATELLITE SHOWS A WEAK S/W EMBEDDED IN THE NW FLOW. RUC SHOWS THAT THE VORT WILL SLOWLY PUSH EAST ACROSS THE CWA THIS AFTERNOON. SO FAR...A FEW PATCHES OF CU HAVE RESPONDED TO THE DISTURBANCE AND MORNING HEATING. OBSERVED SOUNDINGS INDICATE THAT H85 TEMPS ARE NOT AS WARM AS PREVIOUS DAYS...WITH A INVERSION AROUND H75. TEMPS WARMING SLOWER THAN FORECAST WITH WIDESPREAD THIN CIRRUS AND SW NOSING COOLER H85 TEMPS. LATEST LAPS INDICATES THAT TEMPS MAY FALL SHORT OF CURRENT TEMPS BY A FEW DEGREES. BASED ON CURRENT TRENDS AND CLOUD COVER WILL TRIM TEMPS BACK...BUT NOT AS MUCH AS THE FLP SUGGEST. WITH EXPECTED MIXING OF DEWPOINTS...WEAK INVERSION...AND LOWER TEMPS...CONVECTION SHOULD TRIGGER LATE THIS AFTERNOON. GIVEN THE LIMITING FACTORS...ISO SH/TS STILL LOOKS POSSIBLE WITH THE PASSING VORT AND WEAK CAP. && .PREVIOUS DISCUSSION... (ISSUED 231 AM EDT SUN JUL 24 2005) SHORT TERM (TODAY THROUGH TUESDAY NIGHT)... UPPER RIDGE WILL CONTINUE TO AFFECT SE STATES INTO MID WEEK...KEEPING STRONG SHORTWAVES WELL N OF AREA. SURFACE HIGH TO THE NE WILL KEEP AREA IN WEAK N-NE FLOW THIS MORNING...THEN HIGH PRESSURE MOVES OFF THE SE COAST TONIGHT-TOMORROW...PUTTING REGION IN WARMER SOUTHERLY FLOW FOR THE FIRST PART OF THE WEEK. TEMPS WILL BE SLIGHTLY WARMER TODAY...WITH HIGHEST TEMPS STILL EXPECTED MON-TUE. WITH DEW POINTS RANGING FROM THE UPPER 60S N TO THE LOW 70S S...HEAT INDEX VALUES...ALTHOUGH NOT CRITICAL YET...WILL REACH LOW 100S ACROSS S ZONES TODAY. DEW POINTS RISE SLIGHTLY MON WITH HIGHER TEMPS AS WELL...SO EXPECTING SOME AREAS TO EXCEED HEAT INDICES OF 105 FOR SEVERAL HOURS MON AND TUE AFTNS. NO APPARENT TRIGGER FOR CONVECTION OTHER THAN OPROGRAPHICS AND HEATING TODAY BUT AIRMASS REMAINS UNSTABLE THROUGH THE SHORT TERM. ANY SUBTLE DISTURBANCE ALOFT COULD TRIGGER TSTMS AND WITH YESTERDAYS ISOLATED EVE TSTMS IN MIND...WILL GO WITH ISOLD LATE DAY SHWRS AND TSTMS SUN-TUE. LONG TERM (WEDNESDAY THROUGH SATURDAY)... UPPER RIDGE WEAKENS WED...ALLOWING A SERIES OF UPPER SHORTWAVES AND SFC BOUNDARIES TO AFFECT THE AREA. THIS WILL BRING AN INCREASING CHANCE OF CONVECTION TO THE REGION...ALONG WITH COOLER TEMPS AND CURRENT FORECAST HAS THIS TREND WELL COVERED. WILL ONLY MAKE MINOR TWEAKS TO LATER PERIODS. AVIATION... AFTER MVFR FOG...WITH IFR PREDAWN FOG AT KAVL...BURNS OFF BY MID MORNING...SCATTERED CU WILL DOMINATE THE LANDSCAPE. THE ATMOSPHERE WILL BEGIN TO BECOME STAGNANT LATER TODAY...AND THERE IS A GOOD BET THAT SURFACE VISIBILITY WILL BE REDUCED OCCASIONALLY TO MVFR LEVEL IN HAZE FOR PART OF THE AFTERNOON. WE ADVERTISE VCSH AT KAVL/KAND/KGSP BY 22Z...BUT NO REAL TRIGGER TO ADVERTISE ANYTHING MORE THAN THAT AT THE TAF SITES. OUTLOOK PERIOD FEATURES LIGHT WINDS AND VISIBILITY REDUCTION TO 6 MILES ALL LOCATIONS IN HAZE. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SHORT TERM...NED sc AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA NATIONAL WEATHER SERVICE SIOUX FALLS SD 1035 AM CDT SUN JUL 24 2005 .DISCUSSION... SPC JUST DROPPED A SWOMCD FOR THE SRN PART OF MY FA THIS AFTN. NOT SURE ABOUT THE OVERALL SVR THREAT...ALTHOUGH INSTABILITY IS ABUNDANT ESP IN NW IA. AM CONCERNED ABOUT SOME DOWNPOURS. WL UPLOAD SOME NEW GRIDS SOON. FAIRLY POTENT SHORTWV IN THE MID LVLS MOVG ACROSS THE FLOW TODAY. CURRENT ONGOING CONVECTION NOT PICKED UP WELL BY THE NAM OR RUC. HOWEVER THIS AFTN...SHORT RANGE MODELS ARE SUGGESTING SOME LOW LVL INTERACTION WITH THE SHORTWV IN THE SRN CWFA. THIS INCLUDES A HIGH DEGREE OF 0-3KM EHI...STRONG LOW LVL FRONTOGENESIS AND INCREASINGLY VEERING PROFILES FM 0-2KM. IN ADDN...H6-H4 PV GENS UP IN A SW TO NE BAND TO THE NORTH OF THESE LOWER LEVEL FEATURES FM ABOUT BON HOMME COUNTY TO NEAR MARSHALL MN. THIS MATCHES UP WELL WITH SOME H7 FRONTOGENESIS. THEREFORE WL GO SCT OR HIGH CHC POPS POPS THROUGHOUT THE ENTIRE EAST THIS AFTN IN SW MN AND NW IA... ARCING BACK INTO FAR SE SD. WL MAINTAIN HEAT ADVY WHERE IT IS. && .PREV DISCUSSION... CONVECTION CONTINUING OVER FAR WESTERN CWA AT 08Z WITH ADDITIONAL CONVECTION MOVING INTO TRIPP COUNTY. MCK PROFILER FINALLY BEGINNING TO SWING AROUND TO THE SOUTHWEST A LITTLE...WHICH SHOULD DECREASE MOISTURE CONVERGENCE IN THIS AREA. DEEP MOISTURE ALONG SLOWING FRONT HOWEVER WILL ALLOW THIS RAINFALL TO LINGER FOR AWHILE INTO THE MORNING. WILL KEEP HIGH POPS OVER THE WESTERN CWA THROUGH ABOUT LATE MORNING. THIS OF COURSE WILL HAVE SOME IMPLICATIONS ON TEMPERATURES. JUST HOW MUCH IS ALWAYS A TOUGH CALL IN JULY WHERE A COUPLE OF HOURS OF SUN CAN WARM THINGS UP QUICKLY...ESPECIALLY WITH LOW TO MID 20 850MB TEMPS LINGERING AROUND. AS THIS FRONT SLOWS AND KIND OF JUST DIES ACROSS THE AREA OVER THE NEXT 24 HOURS...SFC DEW POINTS WILL AGAIN INCREASE TO VERY UNCOMFORTABLE LEVELS. WILL ISSUE A HEAT ADVISORY ALONG AND SOUTH OF A YANKTON TO SPENCER IOWA LINE FOR TODAY. NORTH OF THIS LINE...WHILE NOT EXACTLY PLEASANT...CLOUD COVER AND PRECIPITATION SHOULD LIMIT THE AMOUNT OF HEATING AND GENERALLY KEEP HEAT INDICES BELOW 100. TONIGHT LOOKS VERY INTERESTING AS CONVECTION LIKELY TO FIRE OVER THE NEBRASKA PANHANDLE REGION...THEN FEED NORTHEAST ALONG MOISTURE/INSTABILITY AXIS. WILL INCREASE POPS TO 60 TO 70 THROUGH THE HEART OF THE CWA...WITH THE LOWEST POPS IN NW IA WHICH SHOULD BE SOUTH OF THE BOUNDARY. SOME CONVECTION SHOULD LINGER INTO MONDAY...THEN REDEVELOPMENT OVER SOUTHEAST SD INTO MN AND IA. TUESDAY COULD ALSO SEE SOME PRECIPITATION LINGERING INTO THE MORNING...AND WILL HAVE POPS TO COVER THIS. OTHERWISE...DECREASING HIGHS ON TUESDAY DUE TO UNFAVORABLE SFC WIND DIRECTION AND 850MB TEMPS AROUND 10 DEGREES C FOR MUCH OF THE CWA. THIS YIELDS 70 TO 75 FOR MUCH OF THE AREA. HAVE ALSO DECREASED HIGHS ON WEDNESDAY A COUPLE DEGREES AS LINGERING COOL AIR SHIFTS EAST. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...HEAT ADVY 1 PM TO 8 PM TODAY FOR SDZ070-071. MN...NONE. IA...HEAT ADVY 1 PM TO 8 PM TODAY FOR IAZ001>003-012>014-020>022- 031-032. NE...HEAT ADVY 1 PM TO 8 PM TODAY FOR NEZ013-014. && $$ MJF/08 sd AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE BURLINGTON VT 1030 AM EDT SUN JUL 24 2005 .SHORT TERM (REST OF TODAY THROUGH TONIGHT)... WL ONLY UPDATE ST LAW VLY TO PTLY SUNNY WITH CI BLOW OFF. OTRW NO UPDATE TO ZONE FORECASTS NEEDED TODAY. HIGH PRES FM SRN QUE TO VA ATTM WL MOV ACRS NEW ENG THIS AFTN AND THEN OFSHR. RETURN SW FLO OF MSTR BEGINS TNGT ON BACKSIDE OF HI. LOW PRES CURRENTLY N OF LK WINNIPEG MOVS E ACRS ONT THIS AFTN AND ERLY TNGT. ASOCD WRMFNT CNTRL GRTLKS...WITH CONCENTRATED AREA OF SHWRS/TSTMS ASSOCD WITH WAA LIFT. CURRENT TRAJ OF TSTM CMPLX WUD TAKE IT S OF OUR AREA AS NOTED ON H/7 12Z OBS WITH NW FLO 20-40KTS. MRNG SOUNDINS IN OUR AREA DRY AND SATL IMAGERY INDCS CI ENTERING WRN PTNS OF NRN NY ATTM. CURRENT FCST INDCS MSTLY SUNNY THIS AFTN AND THEN INTRODUCES CHC TSTMS LATE TNGT...AND THAT STILL LKS REASONABLE. TEMPS ARND 80 THIS AFTN LKS GOOD WITH LGT WINDS AS CURRENTLY FCST. && .PREVIOUS DISCUSSION... (ISSUED 313 AM EDT SUN JUL 24 2005) SYNOPSIS... HI PRESS TO BUILD ACRS ACRS THE FA FROM THE WEST TODAY...THEN OUT TO THE EAST OF THE FA TONITE. TROF (FOR LACK A BETTER TERM) TO MOVE ACRS THE GREAT LKS REGION TONITE...THEN ACRS THE FA ON MON. WK HI PRESS LOOKS TO AFFECT THE FA ON MON NITE. CF TO MOVE ACRS THE GREAT LKS REGION ON TUE. S/W TO MOVE ACRS THE FA ON TUE. SHORT TERM (TODAY THROUGH TUESDAY)... 00-02Z RUC13 SHOWS TEMPS TO GET UP INTO THE 70S-M80S TODAY WITH WESTERLY SFC WINDS BECOMING MORE SOUTHERLY WITH TIME AT 5-15 KTS. T1MAX TEMPS ARE IN THE 80S TODAY. FEW TWEAKS TO FIRST PERIOD TEMPS/WINDS BASED ON THIS DATA AND MESONET OBS. SOME LOW-LVL MSTR TO AFFECT THE FA TODAY. RUC SHOWS NIL PCPN/CAPE ACRS THE FA TODAY WITH MOSUNNY SKIES OTRW. WK H85 WAA TO TAKE PLACE ACRS THE FA THROUGHOUT THE SHORT-TERM PERIOD. SOME LOW-LVL MSTR ADVECTION TO TAKE PLACE ACRS THE FA TODAY...TONITE...AND LATER ON TUE. LOW-LVL MSTR TO INCREASE ACRS THE FA TONITE AND EARLY ON MON...THEN AGAIN LATER ON TUE. LOW-LVL LAPSE RATES TO BE HI ACRS THE FA THIS AFTERNOON. SOME MID-LVL MSTR TO AFFECT THE FA TONITE AND ON TUE. PW VALUES ACRS THE FA LOOK TO BE 1-1.5" TONITE...AROUND AN INCH ON MON/MON NITE...THEN 1-2" ON TUE. 88D MOSAIC SHOWS THAT THE "ROUGE" +SHRA THAT MOVED ACRS PORTIONS OF THE FA FROM THE N-NW ARE GONE ATTM. NY STATE POLICE REPORT SOME FG PATCHES ATTM. WILL HANDLE ANY LINGERING FG ISSUES WITH THE STF. NEXT CHC FOR ANY CONVECTION STILL APPEARS TO BE BY LATER TONITE THRU AT LEAST THE FIRST PART OF MON...THEN AGAIN ON TUE AFTERNOON ACRS MUCH OF THE FA. THE GOING CHC POPS STILL LOOK GOOD FOR THESE PERIODS. WIND FIELDS ALOFT GRADUALLY INCREASE THROUGHOUT THE SHORT-TERM PERIOD...SO ANY CONVECTION BY LATER IN THE PERIOD COULD BE AT LEAST STRONG. T1MAX TEMPS ARE IN THE L80S-L90S ON MON. T1MIN TEMPS ARE MOSTLY IN THE 50S-L60S TONITE AND ON MON NITE. LONG TERM (TUESDAY NIGHT THROUGH SATURDAY)... NO CHANGES TO THE GOING FCST FOR NOW. WRK ZONES AND PRELIM ISC GRIDS AVAILABLE. ALL FINAL PRODUCTS BY 4 AM. AVIATION... IR SATELLITE TRENDS SHOW SCT-BKN070 SHOWING UP AT KBTV/KMPV SHOULD MOVE OUT OF THE AREA 06-08Z. RADIATION FOG FORECAST TO DEVELOP AT KSLK AND KMPV...WITH LIFR CONDITIONS 08-12Z. TEMPO OF IFR VIS AT KMSS AS WINDS GO LIGHT AND THERE IS THE POSSIBILITY OF BR FORMATION. CIG/VIS IMPROVING TO VFR 12-14Z...THEN VFR FOR THE REMAINDER OF THE PERIOD. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SHORT TERM...SFH vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 413 PM EDT SUN JUL 24 2005 .SHORT TERM...TONIGHT AND MONDAY SURFACE ANALYSIS SHOWS WARM FRONT THROUGH MUCH OF THE CWA...WITH WIND GUSTS REALLY PICKING UP BEHIND IT. COLD FRONT BACK FROM NORTHERN LAKE MICHIGAN TO SOUTHERN WISCONSIN...AS YET STILL WITH NO CONVECTIVE ACTIVITY ALONG IT PER REGIONAL RADAR/SATELLITE. PLENTY OF INSTABILITY PER SPC MESOANALYSIS...BUT WITH MID LEVEL CAP PUTTING THE HALT ON ANY CONVECTION. 18Z RUC SHOWS 850MB TEMPS >24C AND 700MB TEMPS >14C. HARD TO GET STORMS GIVEN THAT WARM OF AN AIRMASS. SUBTLE SHORTWAVE RIDGE ALSO APPARENT OVER THE REGION...AHEAD OF A SHORTWAVE/CONVECTIVE VORT NOW MOVING FROM THE DAKOTAS INTO MINNESOTA. CONVECTIVE CHANCES FOR THIS EVENING STILL SEEM PRETTY MARGINAL. DO NOT EXPECT WE WILL GET WARM ENOUGH TO BREAK THE CAP...AND THERE ARE ONLY WEAK UPPER LEVEL FEATURES THAT MAY WORK TO ERODE IT. 18Z RUC/NAM BOTH KEEP TRYING TO SPARK SOMETHING IN THE RIGHT-NOW TIMEFRAME...WITH VISIBLE SATELLITE ONLY SHOWING THINNING CLOUDS. HOWEVER IF SOMETHING DOES GO...IT COULD EASILY BECOME SEVERE GIVEN THE STEEP LAPSE RATES AND FAVORABLE WIND PROFILE. WILL HOLD ON TO A LOW CHANCE POP THIS EVENING GIVEN THE CONVECTIVE AND SEVERE POTENTIAL. TRICKY SETUP AGAIN FOR MONDAY...WITH BOUNDARY STALLING IN THE VICINITY OF LOWER MICHIGAN. GENERAL AGREEMENT AS TO MCS DEVELOPMENT ALONG THE LOW-LEVEL JET AHEAD OF THE PLAINS SHORTWAVE. NOT SURE THAT MCS REMNANTS WOULD MAKE IT INTO SOUTHEAST MICHIGAN...BUT COULD SEE ADDITIONAL DEVELOPMENT DURING THE AFTERNOON AHEAD OF ANY CONVECTIVE VORT THAT MAY BE LEFT OVER. KEPT THE LOW CHANCE ACROSS THE SOUTHERN CWA ON MONDAY. ALSO BUMPED TEMPS UP A BIT ON MONDAY...GIVEN WARM AIR IN PLACE AND FAIR AMOUNT OF INSOLATION. HEAT INDICES WILL AGAIN BE IN THE UPPER 90S...BUT WITH SOMEWHAT MODERATED DEWPOINTS DO NOT EXPECT THEM TO REACH 100F. && .LONG TERM...MONDAY NIGHT THROUGH SUNDAY LOW PRESSURE DEVELOPING IN THE CENTRAL PLAINS ON MONDAY WILL MOVE TOWARD LOWER MICHIGAN MONDAY NIGHT. THIS WILL KEEP CONVECTION ACTIVE IN OUR AREA MAINLY DURING THE OVERNIGHT HOURS THROUGH TUESDAY AFTERNOON. REDEVELOPING SW FLOW IN THE LOW LEVELS WILL DRIVE THE STALLED FRONTAL BOUNDARY BACK NORTH AS A WARM FRONT MONDAY NIGHT. THE STRONG LOW LEVEL JET AND MOISTURE TRANSPORT WILL SUPPORT ANY EXISTING CONVECTIVE COMPLEX OR BE STRONG ENOUGH TO FORCE A NEW ONE OVER LOWER MICHIGAN. STORMS WILL BE POSSIBLE IN AN INCREASINGLY UNSTABLE ENVIRONMENT WITH 850 TO 500 MB LAPSE RATES NEAR 7C/KM AND MOST UNSTABLE CAPE IN THE 1200 TO 1800 J/KG RANGE INTO THE OVERNIGHT HOURS. MOISTURE WILL ALSO REMAIN PLENTIFUL WITH 700 MB DEWPOINT NEAR 8C AND K INDEX NEAR 40. ANY STORMS THAT CAN STAY ROOTED IN THE BOUNDARY LAYER WILL BENEFIT FROM STRONG DIRECTIONAL WIND SHEAR AND HIGH HELICITY. BOTTOM LINE HERE IS THAT CONVECTION LOOKS LIKELY AND HAS A GOOD CHANCE AT BEING ORGANIZED ENOUGH FOR SEVERE WEATHER BOTH ALONG THE WARM FRONT LATE MONDAY NIGHT AND ALONG THE COLD FRONT ON TUESDAY. THE 12Z MODEL TREND IS TOWARD A WEAKER SURFACE WAVE ALONG THE COLD FRONT TUESDAY NIGHT, ESPECIALLY IN THE GFS SOLUTION. THIS ALLOWS A FARTHER SOUTH AND EAST PROGRESSION OF THE FRONT BUT STILL NOT FAST ENOUGH TO RULE OUT A CHANCE OF SHOWERS IN SOUTH SECTIONS OF SE MICHIGAN. THERE IS GOOD MODEL AGREEMENT BETWEEN THE NAM, GFS, AND WRFXX ON THE POSITION OF THE FRONT AND MOISTURE PATTERN FEEDING INTO THE ENTRANCE REGION OF A 130 KT UPPER JET. EXPECT AT LEAST SOME SORT OF SURFACE WAVE ALONG THE FRONT OVER MISSOURI AND TRACKING THROUGH INDIANA AND OHIO LATE TUESDAY NIGHT AND WEDNESDAY MORNING. THE PLAN IS TO FOLLOW A SOLUTION THAT CONFINES THE CHANCE OF RAIN TO SOUTH PORTIONS OF OUR AREA AND HOLD ON TO A LESS AMPLIFIED WAVE. PREVIOUS RUNS OF THE GFS MAY HAVE BEEN OVERDEVELOPED DUE TO CONVECTIVE FEEDBACK. HIGH PRESSURE IS IN PLACE OVER SE MICHIGAN BY WEDNESDAY NIGHT LASTING INTO THURSDAY. LONG RANGE MODEL AGREEMENT IS THEN PRETTY GOOD ON A REINFORCING SURFACE FRONT WASHING OUT IN LOWER MICHIGAN ON THURSDAY LEAVING WEAK HIGH PRESSURE IN PLACE FOR FRIDAY AND SATURDAY. THIS MEANS TEMPERATURES AROUND NORMAL FOR LATE JULY, HIGHS IN THE LOWER 80S AND LOWS AROUND 60. WE'LL START OUT NEXT SUNDAY WITH A CHANCE OF SHOWERS AND STORMS AS THE NEXT LOW PRESSURE SYSTEM TAKES SHAPE IN THE PLAINS AND GREAT LAKES. THE NCEP ENSEMBLE MEMBERS INDICATE THE OPERATIONAL GFS IS ON THE STRONG SIDE WITH THIS NEW SYSTEM WE'LL MONITOR THIS TREND OVER THE NEXT FEW CYCLES. && .PREV DISCUSSION... (ISSUED 135 PM EDT SUN JUL 24 2005) AVIATION... CONVECTION HAS CLEARED OUT OF ALL THE TAF SITES...WITH VFR CONDITIONS PRESENT ACROSS SOUTHEAST MICHIGAN. SOME MVFR/IFR CIGS/VIS ACROSS NORTHERN LOWER...BUT DO NOT EXPECT THESE TO MAKE INROADS TOWARD MBS. WARM FRONT CONTINUES TO PUSH ACROSS LOWER MICHIGAN... WITH AN INCREASING SOUTH/SOUTHWESTERLY FLOW BEHIND IT KEEP THE LOW CLOUDS AT BAY. EXPECT CURRENT MID/HIGH CLOUDS TO THIN OUT OVER THE NEW FEW HOURS. ATMOSPHERE TO THE WEST AND SOUTH OF THE CWA HAS RECOVERED QUICKLY...ALTHOUGH OUTFLOWS/COLD POOLS SHOULD BE MORE PERSISTENT AND SLOW THE WARM FRONTAL PROGRESS A TOUCH ACROSS SOUTHEAST MICHIGAN. WHILE THE ATMOSPHERE CONTINUES TO DESTABILIZE... MID LEVEL CAP IS INHIBITING CONVECTION ALONG THE LEFTOVER OUTFLOWS ACROSS SOUTHERN LOWER...AS WELL AS ALONG THE COLD FRONT UPSTREAM ACROSS WISCONSIN. THIS CAP MAY WEAKEN SUFFICIENTLY TO GET SEE SOME ADDITIONAL STORMS LATE AFTERNOON/EVENING...BUT THE CHANCE REMAINS TOO MINIMAL TO MENTION IN THE TAFS AT THIS POINT. OTHERWISE WILL CONTINUE THE MENTION OF FOG OVERNIGHT. GIVEN THE HIGH DEWPOINTS POOLED ALONG THE FRONTS AND WIDESPREAD PRECIPITATION ACROSS THE CWA...KEPT THE PREDOMINATE MVFR AND BUMPED THE TEMPO GROUP DOWN TO IFR/2SM AROUND SUNRISE. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON UNTIL 8 PM SUNDAY. LAKE ST CLAIR...SMALL CRAFT ADVISORY...LCZ460 UNTIL 8 PM SUNDAY. MI WATERS OF LAKE ERIE...SMALL CRAFT ADVISORY...LEZ444 UNTIL 8 PM SUNDAY. && $$ SHORT TERM...BRAVENDER LONG TERM....BT AVIATION...BRAVENDER mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 338 PM EDT SUN JUL 24 2005 .DISCUSSION... MAIN FORECAST CONCERN IS RAIN CHANCES FOR MONDAY AND MONDAY NIGHT CURRENT WEATHER...18Z WATER VAPOR LOOP AND RUC 500MB HEIGHT ANALYSIS SHOWED A 598 DAM HIGH OVER ARKANSAS WITH NEARLY ZONAL FLOW EXTENDING FROM MONTANA ACROSS TO LAKE SUPERIOR. FURTHER TO THE W AND NW...A SHRTWV TROUGH WAS LOCATED OVER OREGON WITH A STRONGER SHRTWV TROUGH OVER THE NORTHWEST TERRITORIES. AN UPPER LOW WAS ALSO LOCATED OVER NORTH CENTRAL MANITOBA...REFLECTED AT THE SURFACE BY A 996 MB LOW OVER NW ONTARIO. THE ASSOCIATED COLD FRONT EXTENDED SOUTHEAST TO LAKE MICHIGAN. DEWPOINTS AHEAD OF THE COLD FRONT WERE QUITE HIGH THIS MORNING WITH MOST LOCATIONS IN THE LOW 70S (24 HOUR CHANGE IN NEWBERRY OF 25-30 DEGREES). HOWEVER...DRIER AIR IS STILL LAGGING BEHIND ACROSS NORTHERN MN AND NORTH DAKOTA. THIS IS DUE TO A WEAK TROUGH ASSOCIATED WITH CONVECTION THAT OCCURRED THIS MORNING OVER THE DAKOTAS. THIS TROUGH EXTENDS FROM DLH INTO SW MN. PRETTY IMPRESSIVE DRY AIR IN NORTHERN MN THOUGH WITH THE 12Z INL SOUNDING SHOWING A PRECIPITABLE WATER OF 0.61 INCHES AND DEWPOINT DEPRESSIONS OF 15C OR MORE FROM 925MB TO 400MB. ENOUGH DRY AIR DID COME IN BEHIND THE COLD FRONT AND COMBINED WITH MIXING ERODED MUCH OF THE MVFR AND IFR CLOUD DECK THAT WAS OVER UPPER MICHIGAN THIS MORNING. BECAUSE OF THE INCREASED SUNSHINE...TEMPERATURES HAVE WARMED INTO THE 80S. TONIGHT...EXPECTING QUITE WEATHER AS THE AIR THAT WAS PRESENT OVER NORTHERN MN MOVES ACROSS THE CWA. THIS SHOULD HELP KEEP CLEAR SKIES TONIGHT EXCLUDING A FEW EVENING HIGH CIRRUS CLOUDS. WITH THE LOWER PRECIPITABLE WATER AND MOSTLY CLEAR SKIES...TEMPERATURES COULD DROP TO THE DEWPOINTS ADVECTING IN FROM MN. SOME CONCERN THOUGH THAT THE WINDS MAY STAY UP TO PREVENT THIS FROM OCCURRING...ESPECIALLY ACROSS THE NORTHERN U.P.. IF THE WINDS DO DROP OFF...WHICH THE HIGHEST POTENTIAL IS ALONG THE WISCONSIN BORDER WHERE THE HIGH PRESSURE RIDGE BUILDS IN...THERE IS POTENTIAL FOR FOG DUE TO THE RECENT RAINFALL. MINS CLOSE TO GUIDANCE. MONDAY INTO MONDAY NIGHT...SHRTWV TROUGH OVER OREGON WILL PUSH EAST ACROSS MONTANA TONIGHT...ALLOWING FOR CONVECTION TO FIRE ACROSS NORTH DAKOTA. THIS AREA OF CONVECTION IS PROGGED TO CONTINUE EASTWARD DURING THE DAY ON MONDAY...PERHAPS WEAKENING SOME AS THE BETTER THERMODYNAMIC FORCING SHIFTS TO SOUTHERN MN AND WESTERN WI. SOME OF THE CONVECTION MAY MAKE INTO THE WESTERN U.P. LATE IN THE AFTERNOON ON MONDAY DUE TO CONTINUED ISENTROPIC LIFTING AND DEVELOPING FRONTOGENESIS...SO HAVE MAINTAINED A CHANCE OF SHOWERS AND THUNDERSTORMS. HOWEVER...GIVEN THE INITIAL DRY AIR LEADING TO LITTLE IF ANY ELEVATED INSTABILITY...IT IS POSSIBLE THAT MONDAY WILL BE DRY ACROSS THE FORECAST AREA. 850MB TEMPS AROUND 16C COMBINED WITH PLENTY OF MORNING SUNSHINE BEFORE THE CLOUDS FROM THE CONVECTION MOVE IN WILL ALLOW TEMPERATURES TO EASILY RISE INTO THE 80S. WILL CONTINUE THE CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE CWA MONDAY NIGHT AS MID LEVEL FRONTOGENESIS...UPPER JET FORCING AND ISENTROPIC LIFT ARE JUXTAPOSED. ALTHOUGH MODEL QPF FROM THE NAM AND GFS IS NOT THAT GREAT OVER THE CWA...THEY SHOW THE SAME IDENTICAL FEATURES MENTIONED...SUGGESTING THAT THE CHANCE IS DEFINITELY WARRANTED. SPC DAY 2 OUTLOOK AS A TIGHT GRADIENT IN SEVERE PROBABILITIES ACROSS SOUTHERN MENOMINEE COUNTY (STEPHENSON IN 15%...MENOMINEE 25%)...WHICH IS REASONABLE GIVEN THAT THE BETTER PROBABILITIES FOR SEVERE LOOK TO BE IN WISCONSIN INTO LOWER MICHIGAN. ANY MOVEMENT NORTH OF THESE FEATURES MAY RESULT IN SHIFTING THESE PROBABILITIES NORTHWARD. HAVE NOT INCLUDED ANY MENTION OF SEVERE AT THE MOMENT IN THE HWO. THERE MAY BE A DIMINISHING TREND OUT IN THE WEST AFTER MIDNIGHT AS FORCING MECHANISMS MOVE TO THE SOUTHEAST. HAVE INCLUDED THIS IN THE FORECAST. TUESDAY...WILL LEAVE IN AN EARLY CHANCE OF SHOWERS AND THUNDERSTORMS ALONG LAKE MICHIGAN IN CASE OF SLOWER MOVEMENT. THEN ANOTHER BIG DRY SURGE IS PROGGED BY THE NAM/GFS TO MOVE INTO THE CWA FROM THE PLAINS WITH PRECIPITABLE WATER DROPPING TO 0.5 INCHES BY AFTERNOON. THIS DRY AIR ADVECTION WILL BE ACCOMPANIED BY COOLER AIR AS 850MB TEMPS FALL TO 6 TO 8C BY 18Z. THEREFORE...EXPECTING TEMPERATURES ACROSS THE NORTH HALF OF THE U.P. TO ONLY RISE INTO THE 60S. GUSTY NORTHERLY WINDS BETWEEN HIGH PRESSURE DROPPING INTO THE PLAINS AND THE SURFACE FRONT OVER NORTHERN LOWER MICHIGAN INTO ILLINOIS MAY MAKE CONDITIONS FEEL MORE LIKE FALL TOO IN COMPARISON TO WHAT WE HAVE HAD RECENTLY. TUESDAY NIGHT AND WEDNESDAY...SHRTWV TROUGH CURRENTLY OVER THE NORTHWEST TERRITORIES IS PROGGED TO DROP INTO CENTRAL MANITOBA BY 12Z WED RESULTING...IN LOW PRESSURE OVER NE MANITOBA AND A TRAILING COLD FRONT INTO NORTH DAKOTA. UPPER MICHIGAN IS EXPECTED TO BE UNDER HIGH PRESSURE AND DRY AIR AT THE TIME...ALLOWING TEMPERATURES TO DROP INTO THE 40S AWAY FROM THE LAKES. SHRTWV TROUGH ALONG WITH THE ASSOCIATED COLD FRONT IS EXPECTED TO DROP INTO FAR WESTERN ONTARIO/NORTHERN MINNESOTA BY WEDNESDAY EVENING. ALTHOUGH THE NAM SUGGESTS SOME RAIN COMING INTO THE WESTERN U.P. WEDNESDAY AFTERNOON...RIGHT NOW WILL FOLLOW THE SLOWER SOLUTIONS OF THE UKMET/CANADIAN/GFS WHICH KEEP ANY PRECIPITATION CHANCES ASSOCIATED WITH THE COLD FRONT UNTIL WEDNESDAY NIGHT. NONETHELESS...INCREASING CLOUDS ARE EXPECTED ACROSS THE WESTERN U.P.. TEMPERATURES SHOULD BE A FEW DEGREES WARMER THAN ON TUESDAY GIVEN THAT THE AIRMASS WILL HAVE WARMED (850MB TEMPS IN THE 7 TO 10C RANGE). EXTENDED (THU THROUGH SUN)...MODELS SUGGEST A BREAKDOWN OF THE RIDGE OVER THE GREENLAND AREA...WHICH HELPS TO TURN THE FLOW MORE ZONAL ACROSS THE NORTHERN TIER OF THE U.S. BY SATURDAY. HOWEVER...A TROUGH LINGERING ACROSS THE GULF OF ALASKA WOULD ALLOW FOR A RIDGE TO PERSIST ACROSS THE NORTHERN ROCKIES...WHICH THE MODELS SHOW REDEVELOPING SATURDAY AND SUNDAY. PRETTY GOOD AGREEMENT EXISTS AMONGST ALL OF THE MODELS...ALTHOUGH THE 00Z GFS SEEMS A BIT TOO AMPLIFIED WITH A TROUGH MOVING THROUGH THE GREAT LAKES SATURDAY NIGHT. PER HPC...WILL FOLLOW THE 00Z ECMWF. THE 06Z GFS IS QUITE SIMILAR TO THE ECMWF FOR UPPER MICHIGAN...THEREFORE WILL FOLLOW THE GFS. SHRTWV TROUGH IS PROGGED TO MOVE SE ACROSS NORTHERN ONTARIO/LAKE SUPERIOR THU MORNING...BRINGING A COLD FRONT ACROSS UPPER MICHIGAN. HAVE INCLUDED A CHANCE FOR SHOWERS AND THUNDERSTORMS WEDNESDAY NIGHT AS THE FRONT MOVES ACROSS...BUT KEPT THINGS DRY FOR NOW ON THURSDAY THINKING THAT THE FRONT WILL HAVE PASSED. HIGH PRESSURE WILL BUILD IN ACROSS THE CWA THURSDAY NIGHT INTO FRIDAY. MEANWHILE...LOW PRESSURE IS EXPECTED TO DEVELOP ACROSS THE NORTHERN PLAINS ON FRIDAY WITH A WARM FRONT MOVING ACROSS THE CWA FRIDAY NIGHT. WILL INCLUDE A CHANCE OF SHOWERS AND THUNDERSTORMS WITH THIS. AS RIDGING REDEVELOPS OVER THE NORTHERN ROCKIES ON SATURDAY...THE LOW WEAKENS WITH A WEAK TROUGH/COLD FRONT SITUATED OVER WESTERN LAKE SUPERIOR BY SATURDAY EVENING. WILL ALSO HAVE A CHANCE OF SHOWERS AND THUNDERSTORMS FOR THIS FEATURE AS IT MOVES ACROSS THE CWA SATURDAY NIGHT. SHOULD BE A WARM DAY SATURDAY AHEAD OF THE FRONT AS 850MB TEMPS CLIMB TO AROUND 16C. HIGH PRESSURE BUILDS IN BEHIND THE FRONT FOR SUNDAY AS THE UPPER FLOW TURNS NORTHWESTERLY...ALLOWING FOR 850MB TEMPS TO COOL BACK DOWN TO 8-10C. NOTICED THAT THE 12Z GFS IS SLOWER WITH THE FRONT AND HIGH PRESSURE. WILL NOT JUMP ON THIS QUITE YET...BUT ADJUSTMENTS MAY BE REQUIRED LATER. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ AJ mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 135 PM EDT SUN JUL 24 2005 .AVIATION... CONVECTION HAS CLEARED OUT OF ALL THE TAF SITES...WITH VFR CONDITIONS PRESENT ACROSS SOUTHEAST MICHIGAN. SOME MVFR/IFR CIGS/VIS ACROSS NORTHERN LOWER...BUT DO NOT EXPECT THESE TO MAKE INROADS TOWARD MBS. WARM FRONT CONTINUES TO PUSH ACROSS LOWER MICHIGAN... WITH AN INCREASING SOUTH/SOUTHWESTERLY FLOW BEHIND IT KEEP THE LOW CLOUDS AT BAY. EXPECT CURRENT MID/HIGH CLOUDS TO THIN OUT OVER THE NEW FEW HOURS. ATMOSPHERE TO THE WEST AND SOUTH OF THE CWA HAS RECOVERED QUICKLY...ALTHOUGH OUTFLOWS/COLD POOLS SHOULD BE MORE PERSISTENT AND SLOW THE WARM FRONTAL PROGRESS A TOUCH ACROSS SOUTHEAST MICHIGAN. WHILE THE ATMOSPHERE CONTINUES TO DESTABILIZE... MID LEVEL CAP IS INHIBITING CONVECTION ALONG THE LEFTOVER OUTFLOWS ACROSS SOUTHERN LOWER...AS WELL AS ALONG THE COLD FRONT UPSTREAM ACROSS WISCONSIN. THIS CAP MAY WEAKEN SUFFICIENTLY TO GET SEE SOME ADDITIONAL STORMS LATE AFTERNOON/EVENING...BUT THE CHANCE REMAINS TOO MINIMAL TO MENTION IN THE TAFS AT THIS POINT. OTHERWISE WILL CONTINUE THE MENTION OF FOG OVERNIGHT. GIVEN THE HIGH DEWPOINTS POOLED ALONG THE FRONTS AND WIDESPREAD PRECIPITATION ACROSS THE CWA...KEPT THE PREDOMINATE MVFR AND BUMPED THE TEMPO GROUP DOWN TO IFR/2SM AROUND SUNRISE. && .UPDATE...1135 AM EDT SUN JUL 24 2005 CLUSTER OF STORMS CONTINUES TO PROGRESS ACROSS SOUTHEAST MICHIGAN. COVERAGE HAS DIMINISHED...ESPECIALLY ON THE SOUTHWEST FLANK OF THE STORMS...GIVEN A STRONGER CAP IN PLACE. ADDITIONAL STORMS CONTINUE TO PERCOLATE FROM NORTHERN LOWER THROUGH LAKE HURON ALONG THE LEAD EDGE OF THE 700MB THETA-E RIDGE INDICATED BY THE 12Z RUC. AT THIS POINT NO ACTIVITY IS OCCURRING TO THE SOUTHWEST...UNDER MORE CAPPED ATMOSPHERE WITH 850MB TEMPS >22C/700MB TEMPS>12C. QUESTION REMAINS WHETHER WE WILL BE ABLE TO BREAK THROUGH THIS CAP AS THE COLD FRONT SWINGS IN FROM WISCONSIN. 12Z NAM/RUC BOTH SHOW CONVECTION DEVELOPING LATE THIS AFTERNOON...WHILE 06Z GFS/00Z WRF-XX BOTH KEEP IT DRY. WATER VAPOR LOOP SHOWS A SHORTWAVE/CONVECTIVE VORT OVER THE NORTHERN PLAINS...LEADING TO SOME STORMS THERE WELL UPSTREAM. SUBTLE SHORTWAVE RIDGE OVER THE WESTERN GREAT LAKES...LEADING TO SOME SUBSIDENCE THAT COULD FURTHER INHIBIT CONVECTION OVER THE CENTRAL GREAT LAKES. 00Z NCAR 4KM WRF /WHICH DID HOLD ONTO THE MORNING CONVECTION FOR TOO LONG/ DID DEVELOPS STORMS ACROSS THE NORTHERN PLAINS/UPPER MISSISSIPPI VALLEY THIS AFTERNOON/EVENING IN THE VICINITY OF THE UPPER WAVE...BUT STRUGGLES FARTHER EAST UNDER THE UPPER RIDGE. FEELING IS THAT WE WILL REMAIN DRY ONCE THE CURRENT ONGOING ACTIVITY MOVES OUT. HOWEVER GIVEN THE CONTINUED POTENTIAL FOR SEVERE WEATHER /850MB WINDS 35-40KTS...NEARLY UNIDIRECTIONAL FLOW...DRY MID-LEVEL AIR...AND IMPRESSIVE CAPE BUILDING UNDER THE CAP/ AND A COUPLE DIFFERENT MODELS INDICATING THE CAP BREAKING... WILL ADD A LOW CHANCE POP FOR THIS AFTERNOON/EVENING. CONSEQUENTLY WILL CONTINUE THE MENTION OF POSSIBLE SEVERE WEATHER IN THE HWO. OTHER QUESTION WAS WITH TEMPERATURES AND HEAT INDICES. VIS SATELLITE SHOWS CLOUD SHIELD THINNING ACROSS SOUTHWEST LOWER...WHERE AN INCREASING SOUTHWESTERLY FLOW HAS ALSO PICKED UP. HEAT INDICES ARE ALREADY BREAKING 100F ACROSS ILLINOIS AS OF 15Z. HOWEVER...STILL DO NOT EXPECT SOUTHEAST MICHIGAN WILL WARM UP ENOUGH TO REACH HEAT ADVISORY CRITERIA. REST OF THE CURRENT FORECAST LOOKS ON TRACK. && .SHORT TERM...TODAY AND TONIGHT...ISSUED AT 335 AM EDT GOOD AGREEMENT ON BRINGING ACTIVE WARM FRONT INTO LOWER MICHIGAN THIS MORNING...WITH SCATTERED SHOWERS/THUNDERSTORMS BEING REPLACED BY A RATHER POTENT MCS SLIDING SOUTHEAST AROUND UPPER RIDGE. WILL UP THUNDERSTORM CHANCES TO 80-90% FOR MUCH OF CWA THIS MORNING AND TAPER TO ABOUT 60% FAR SOUTHWEST COUNTIES. THIS ACTIVITY WILL MAKE TEMPERATURE FORECASTING VERY DIFFICULT TODAY AS CLOUD COVER/PRECIPITATION KEEP TEMPERATURES DOWN THROUGH THE MORNING AND LEFTOVER OUTFLOW MONKEYS WITH SOUTHWEST FLOW THAT IS EXPECTED TO DEVELOP IN THE WAKE OF THE PASSING WARM FRONT. WILL EDGE TEMPERATURES DOWN SEVERAL DEGREES BASED ON TRENDS IN THE 00Z MODEL RUNS. THIS ADJUSTMENT WILL BRING ALL AREAS BELOW HEAT ADVISORY CRITERIA WITH HEAT INDICES INTO THE 95-100 DEGREE RANGE ACROSS THE SOUTHWEST CWA THIS AFTERNOON. THIS WILL HAVE TO BE RE-EVALUATED BASED ON WHAT HAPPENS WITH THE THUNDERSTORMS OVER THE NEXT 6-9 HOURS. AT THIS TIME IT APPEARS THAT THE NAM/S MORE SOUTHERN EXTENT OF THUNDERSTORMS IS WORKING OUT...WHICH LENDS SUPPORT FOR A "LESS HOT" FORECAST. THAT SAID...CONDITIONS WON/T BE PLEASANT AS LOWER/MID 70 DEWPOINTS BRING HUMIDITY LEVELS UP DRAMATICALLY AS COMPARED TO THE PAST FEW DAYS. GIVEN THIS AIRMASS...WILL UP LOW TEMPERATURES A DEGREE OR TWO FOR TONIGHT...WHICH IS SUPPORTED BY GUIDANCE...ESPECIALLY ACROSS THE SOUTHERN CWA WHERE FRONT WILL BE STALLING AND LOW LEVEL MOISTURE POOLING. && .LONG TERM...MONDAY THROUGH SATURDAY...ISSUED AT 335 AM EDT AS TO BE EXPECTED...MESOSCALE FEATURES AND SHORT WAVE INITIALIZATIONS HAVE RESULTED IN A SHIFT IN THE GOING FORECAST. THIS UPCOMING FIRST HALF OF THE WEEK WILL BE IMPACTED BY A FEW SYNOPTIC BOUNDARIES AND A COUPLE OF MCS/S...SEVERE POTENTIAL LOOMING AND HEAVY RAINFALL PRODUCERS. THIS AFOREMENTIONED FRONTAL BOUNDARY WILL BE WAVERING ACROSS THE GREAT LAKES REGION AS EVENTUAL TRACK OF ONGOING MCS WILL DICTATE JUST HOW FAR SOUTH THE BOUNDARY GETS ON MONDAY. STILL EXPECT THE BOUNDARY TO REMAIN CLOSE ENOUGH TO THE SOUTHERN COUNTIES TO WARRANT OUR CONTINUED CHANCE FOR CONVECTION. UPSTREAM CAPES (IE OVER INDIANA AND OHIO) ARE PROGGED TO BE BETWEEN 3000-4000 J/KG AND WITH INCREASING LOW LEVEL JET...POTENTIAL FOR SOME OF THESE CELLS TO CROSS OVER THE WARM FRONT WHICH COULD PROVE TO BE INTERESTING... FURTHER UPSTREAM, AS ANOTHER WAVE INTERACTS WITH THE INSTABILITY, WE SHOULD SEE ANOTHER MCS EVOLVE AND TRACK TOWARD THE LOCAL AREA MONDAY NIGHT. PWATS FROM THE VARIOUS NUMERICAL MODELS STILL HOLD ONTO THE 2" (EVEN HIGHER) WITH K-INDICES TOUCHING 40. SO HEAVY RAINFALL POTENTIAL REMAINS AN ADDITIONAL CONCERN. THIS SYSTEM TRACKS ACROSS THE AREA ON TUESDAY AND LEAVING US UNDER CLOUDY SKIES, HIGH MOISTURE CONTENT AND ADDITIONAL CONVECTION DEVELOPING. CONFIDENCE IN EITHER NUMERICAL MODEL IS QUITE LOW, NEVERTHELESS, THEY ALL SUGGEST THIS FRONTAL BOUNDARY WILL WAIVER AS THE LOW LEVEL JET UPSTREAM WILL LIKELY DEVELOP ANOTHER MCS TOWARD TUESDAY NIGHT AS ONE LAST SHORT WAVE COMES DOWN INTO THE WESTERLIES. MODEL TRENDS HAVE POINTED TO MUCH LESS AMPLIFICATION FOR WEDNESDAY WHICH LEAVES OPEN THE POSSIBILITY FOR ADDITIONAL CONVECTION (PERHAPS THE MCS) INTO WEDNESDAY MORNING. AFTER COLLABORATING WITH SURROUNDING OFFICES, HAVE DECIDED TO ADD THAT TO THE GRIDS AND LOWER TEMPS WITH COOL ADVECTION UNDERWAY BY AFTERNOON. SORRY FOR THE BREVITY AS WE ARE CLOSELY MONITORING UPSTREAM ACTIVITY THIS SUNDAY MORNING. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...SMALL CRAFT ADVISORY...NEARSHORE WATERS FROM PORT AUSTIN TO PORT HURON...7 AM SUNDAY TO 5 PM SUNDAY. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....BRAVENDER UPDATE.......BRAVENDER SHORT TERM...DG LONG TERM....BGM HTTP://WEATHER.GOV/DETROIT (ALL LOWER CASE) mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND RAPIDS MI 1240 PM EDT SUN JUL 24 2005 .UPDATE... KEPT THE HEAT ADVISORY GOING. CURRENTLY MOST OBSERVATIONS SITES IN THE ADVISORY AREA ARE IN THE 90S FOR HEAT INDICES AND IT IS JUST A MATTER OF TIME TILL THEY HIT 100. ELSEWHERE...I WILL BE WATCHING CLOUD TRENDS AS LOWER CLOUDS ARE HOLDING BACK TEMPERATURES. I MAY EXPAND THE HEADLINES AS CLOUDS DISSIPATE. WITH IT ALREADY QUITE UNSTABLE...LIFTED INDEX VALUES LOWER THAN MINUS 4...AND A BOUNDARY SLIPPING SOUTHEAST FROM WISCONSIN...I ADDED SOME THUNDERSTORMS TO THE AFTERNOON FORECAST. IT IS WARM ALOFT...BUT RUC SOUNDINGS SHOW NO INHIBITION THIS AFTERNOON AND SOME CAPE BELOW 700 MB. A LAKE BREEZE MAY ALSO SET UP...ENHANCING THE BOUNDARY LAYER LIFT. IF CONVECTION DOES DEVELOP...IT COULD BECOME ORGANIZED AS BULK SHEAR VALUES 0 TO 6 KM VALUES ARE IN EXCESS OF 40 KNOTS. .GRR WATCHES/WARNINGS/ADVISORIES...HEAT ADVISORY IN EFFECT FOR THIS AFTERNOON AND EARLY EVENING FOR THE SOUTHWEST CORNER OF THE CWFA AND CALHOUN COUNTY. SMALL CRAFT ADVISORY IN EFFECT FROM ST JOSEPH TO MANISTEE. && $$ MJS mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 300 PM CDT SUN JUL 24 2005 .DISCUSSION...FORECAST FOCUS ON HEAT THIS EVENING...AND ON SMALL THUNDERSTORM CHANCES TONIGHT AND THEN BETTER THUNDERSTORM CHANCES MONDAY INTO TUESDAY. HEAT THE THEN MAIN PROBLEM THIS EVENING. SOME STRATO CUMULUS JUST UNDER THE CAP ALONG THE NORTHWEST AND FAR NORTH PORTIONS OF OUR FORECAST AREA. ALTHOUGH THIS KEEPING TEMPERATURES DOWN A BIT...DEWPOINTS ARE POOLING THERE ALONG BOUNDARY. AS SUCH WILL LEAVE ALL HEADLINES GO UNTIL THERE EXPIRATION. ALSO THE BREEZY CONDITIONS SHOULD SUBSIDE AS THE LOW LEVEL JET WEAKENS CONSIDERABLY BY EVENING. NEXT IS THE PROBLEM OF THUNDERSTORMS. AM NOT CONVINCED THEY WILL HAPPEN. CURRENT RUC STILL HOLDING ON TO CAP...DESPITE NAM SOUNDINGS SHOWING CAP WEAKENS. ALSO LACK OF LOW LEVEL CONVERGENCE AS 850 MB LOW LEVEL JET. STILL IT'S HARD TO IGNORE THE 4000 J/KG CAPE VALUES. MODELS SLOWING REDEVELOPMENT OF 850 MB LOW LEVEL JET AHEAD OF NEXT SHORTWAVE IN THE UPPER JET. AS RESULT TONIGHT JUST MAY REMAIN DRY. TOWARDS MORNING THE SAGGING BOUNDARY SHOULD BECOME STATIONARY AROUND THE IL BORDER AREA AND WITH THE NOSE OF THE LOW LEVEL JET PUSHING TROUGH THE FORECAST AREA IT WILL BE HARD TO TIME THE BEGINNING OF THE NEXT POTENTIAL ROUND OF THUNDERSTORMS. THIS ALSO HAS IMPLICATIONS ON HIGH TEMPERATURES MONDAY. SOMEWHAT COOLER EAST FLOW OFF NAM MODEL WITH A MORE SOUTHERLY AND WARMER FLOW ON THE GFS. BOTH MODELS INCREASE THE THUNDERSTORM THREAT BY MONDAY EVENING. THEN BOTH MODELS ARE NOW IN AGREEMENT ON A FASTER COLD FRONTAL PASSAGE WHICH WOULD END THE CHANCE OF STORMS SOMETIME DURING THE DAY TUESDAY. && .MKX WATCHES/WARNINGS/ADVISORIES... EXCESSIVE HEAT WARNING UNTIL 10 PM ZONES 64>66...69>72. HEAT ADVISORY TIL 10 PM ZONES 46-47...51-52...56>60...62-63...67-68. && $$ HENTZ wi