Forecast Discussions mentioning "ACARS", "MDCRS", "AIRCRAFT", "TAMDAR", or "AMDAR" received at FSL on 08/05/07

AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
130 PM PDT FRI AUG 3 2007 .SYNOPSIS... MONSOON MOISTURE IS BEING PUSHED EAST BY AN UPPER LEVEL TROUGH OVER THE PACIFIC...BRINGING DRIER CONDITIONS TO THE MOUNTAINS AND DESERTS. COASTAL STRATUS WILL BECOME SLIGHTLY MORE EXTENSIVE AND PERSISTENT OVER THE NEXT SEVERAL DAYS AS THE MARINE LAYER DEEPENS. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES. EARLY MORNING STRATUS FROM A MODERATELY DEEP MARINE LAYER STRETCHED WELL INTO THE SAN DIEGO COUNTY VALLEYS AND THEN DISSIPATED RAPIDLY BY 9 AM TODAY. A SOLID BANK OF STRATUS REMAINS ENTRENCHED OFFSHORE. SCATTERED CUMULUS HAVE DEVELOPED MAINLY OVER THE HIGHER ELEVATIONS OF THE MOUNTAINS. THE OUTER FRINGES OF MONSOON MOISTURE WERE NEARBY AND JUST EAST OF THE FORECAST AREA WITH CUMULUS SHOWING LITTLE VERTICAL DEVELOPMENT THUS FAR. 12Z NKX SOUNDING DRIER AND MORE STABLE. ONSHORE PRESSURE GRADIENTS WITH SAN-IPL APPROX 6 MB. A DRIER AND COOLER FORECAST REMAINS ON TAP FOR THIS WEEKEND INTO EARLY NEXT WEEK AS A BROAD UPPER TROUGH HOVERS NEAR THE WEST COAST. TEMPERATURES WILL AVERAGE SEVERAL DEGREES BELOW NORMAL. THE TROUGH DEEPENS SOUTHWARD INTO CA THROUGH SUNDAY NIGHT AND SOUTHWEST FLOW ALOFT SHOULD KEEP THE MONSOON SHIFTED OFF TO THE EAST. AN EASTERLY WAVE FEATURE COMING UP FROM NRN MEXICO IS FORECAST TO GET CAUGHT UP IN THE FLOW BUT PASS MAINLY OVER AZ. THE MARINE LAYER WILL DEEPEN A BIT MORE AND GENERALLY ALLOW FOR MORE EXTENSIVE NIGHT AND MORNING LOW CLOUDS. EARLY MORN STRATUS SHOULD EXTEND WELL INLAND DURING THE WEEKEND. LITTLE CHANGE IN THE FLOW PATTERN THROUGH THE END OF NEXT WEEK WITH TEMPS NEAR OR SLIGHTLY BELOW NORMAL. && .AVIATION... 031900Z...MDCRS SOUNDINGS INDICATE THE MARINE LAYER DEPTH HAD LOWERED TO AROUND 1400 FEET FROM THIS MORNING. EXPECT SOME DEEPENING TO AROUND 2000 FEET TONIGHT IN RESPONSE TO A COASTAL EDDY THAT IS EXPECTED TO DEVELOP. STRATUS WITH BASES AROUND 1200 FEET MSL SHOULD PUSH BACK ONTO THE COAST AROUND SUNSET AND INLAND DURING THE EVENING. COASTAL AIRPORTS SUCH AS KSAN...KCRQ AND KSNA SHOULD RECEIVING CEILINGS BETWEEN 04Z AND 07Z. STRATUS COULD REACH THE VICINITY OF KONT BY SUNRISE SATURDAY MORNING. EXPECT SIMILAR CLEARING SATURDAY MORNING. ABOVE THE MARINE LAYER...VFR CONDITIONS WITH A MOSTLY CLEAR SKY AND UNRESTRICTED VISIBILITIES THROUGH SATURDAY. SOME AFTERNOON CU OVER THE MOUNTAINS...BASES AROUND FL100. HORTON && .SGX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...LAVIS AVIATION/MARINE...HORTON
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
930 AM PDT FRI AUG 3 2007 .SYNOPSIS... MONSOON MOISTURE IS GETTING FORCED EAST BY AN UPPER LEVEL TROUGH OVER THE PACIFIC. THIS WILL END THE THUNDERSTORM THREAT AND BRING LOWER HUMIDITIES TO THE MOUNTAINS AND DESERTS THIS WEEKEND. COASTAL CLOUDS WILL BECOME SLIGHTLY MORE EXTENSIVE AND PERSISTENT OVER THE NEXT SEVERAL DAYS AS THE MARINE LAYER DEEPENS. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES. STRATUS REACHED ITS MAXIMUM EXTENT NEAR SUNRISE...STRETCHING WELL INTO THE SAN DIEGO COUNTY VALLEYS AND TO THE EXTREME SW CORNER OF SW SAN BERNARDINO CO NEAR CHINO. DISSIPATION HAS BEEN RAPID EARLY THIS MORN WITH MUCH OF THE CLOUD DECK ALREADY RETREATED TO THE COASTLINE AS OF 9 AM. A SOLID BANK OF STRATUS WAS IN PLACE OFFSHORE. THERE WERE ALSO SCATTERED HIGH CLOUDS. THE 12Z NKX SOUNDING SHOWED A DRIER AND MORE STABLE AIRMASS COMPARED TO 24 HRS AGO...SOME LIGHT EAST FLOW LINGERING BETWEEN 10-15KFT AND LIGHT N-NW WINDS FROM 5-10KFT. ONSHORE PRESSURE GRADIENTS WITH SAN-IPL APPROX 5 MB. THE OUTER FRINGES OF THE MONSOON MOISTURE WERE STILL CLOSE TO THE FORECAST AREA THIS MORN. SURFACE DEWPOINTS RUNNING AROUND 50 DEGF IN THE COACHELLA VALLEY...DOWN SIGNIFICANTLY FROM YESTERDAY...WHILE FURTHER TO SE THE DEWPT AT IMPERIAL WAS STILL NEAR 70. WILL KEEP MENTION OF CONVECTION OUT FOR THIS AFTN BUT MONITOR FOR SIGNS OF ANY CHANGE MAINLY NEAR THE SPINE OF THE SAN DIEGO CO MOUNTAINS. OTHERWISE A DRIER AND COOLER FORECAST REMAINS ON TAP THIS WEEKEND INTO EARLY NEXT WEEK AS A BROAD UPPER TROUGH HOVERS NEAR THE WEST COAST. TEMPERATURES WILL AVERAGE SEVERAL DEGREES BELOW NORMAL. SOUTHWEST FLOW ALOFT WILL KEEP THE MONSOON SHIFTED OFF TO THE EAST. THE MARINE LAYER WILL DEEPEN A BIT MORE AND GENERALLY ALLOW FOR MORE EXTENSIVE NIGHT AND MORNING LOW CLOUDS. && .AVIATION... 031500Z...MORNING TOP REPORTS AND MDCRS SOUNDINGS PUT THE TOP OF THE MARINE LAYER AROUND 1800 FEET MSL. LITTLE CHANGE IN THE DEPTH OF THE MARINE LAYER IS EXPECTED THROUGH THE WEEKEND. STRATUS WITH BASES AROUND 1400 FEET MSL SHOULD CLEAR TO THE COAST BETWEEN 15Z AND 18Z...THEN PUSH BACK ONTO THE COAST AROUND SUNSET AND INLAND DURING THE EVENING. COASTAL AIRPORTS SUCH AS KSAN...KCRQ AND KSNA SHOULD RECEIVING CEILINGS BETWEEN 04Z AND 07Z. STRATUS COULD REACH THE VICINITY OF KONT BY SUNRISE SATURDAY MORNING. EXPECT SIMILAR CLEARING SATURDAY MORNING. ABOVE THE MARINE LAYER...VFR CONDITIONS WITH A MOSTLY CLEAR SKY AND UNRESTRICTED VISIBILITIES THROUGH SATURDAY. HORTON && .SGX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...LAVIS AVIATION/MARINE...HORTON
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
940 PM PDT THU AUG 2 2007 .UPDATE...NO SIGNIFICANT CHANGE TO THE FORECAST THIS EVENING AS THINGS ARE RELATIVELY QUIET. 00Z KVBG SOUNDING AND LAX ACARS SHOW THE MARINE LAYER HANGING AROUND 1200 FEET BUT LOW CLOUDS NEVER LEFT THE OXNARD COASTAL PLAIN AND QUICKLY MOVED BACK INTO DOWNTOWN AFTER SUNSET. CLOUDS ALSO THICKENING UP ALONG THE CENTRAL COAST WITH KSMX SHOWING BROKEN CEILINGS. INCREASED WIND SPEEDS SOME THIS EVENING FOR THE COASTAL WATERS AROUND POINT CONCEPTION AS NORTHWEST WINDS GUSTING 20-25 KT AT TIMES AT THE WEST CHANNEL BUOY. OTHERWISE... TYPICAL DESERT WINDS STARTING TO DIMINISH THIS HOUR AND LITTLE OTHER SIGNIFICANT WEATHER PROBLEMS. LOOKING FOR THE MARINE LAYER TO DEEPEN AGAIN OVERNIGHT WITH ALL COASTAL AREAS AND MANY VALLEY LOCATIONS UNDER A BLANKET OF CLOUDS TO START OFF THE DAY ON FRIDAY. ONE ISSUE TO PASS ALONG TO FUTURE SHIFTS IS THE VERY DRY AIR HEADED FOR THE HIGHER ELEVATIONS BY SUNDAY NIGHT AND MONDAY. MODEL CROSS SECTIONS SHOW VERY POOR RECOVERIES AT NIGHT AND SINGLE DIGIT HUMIDITIES FOR THIS STRETCH. THIS MAY BRING SOME HEIGHTENED FIRE WEATHER CONDITIONS TO THE MOUNTAINS. ...PREVIOUS DISCUSSION... AS FOR WINDS...THE ONSHORE FLOW SHOULD PRODUCE SOME GUSTY AFTERNOON AND EVENING WINDS ACROSS THE MOUNTAINS AND ANTELOPE VALLEY. HOWEVER DO NOT ANTICIPATE ANYTHING APPROACHING ADVISORY LEVELS AT THIS TIME. LONG TERM (MONDAY THROUGH THURSDAY)... UPPER TROUGH WILL CONTINUE OVER THE WEST COAST THROUGH TUESDAY... BRINGING CONTINUED DRY CONDITIONS...COASTAL MARINE LAYER AND BELOW NORMAL TEMPS. ON WEDNESDAY AND THURSDAY...THE UPPER TROUGH IS FORECAST TO WEAKEN. DRY CONDITIONS WILL CONTINUE WEDNESDAY/THURSDAY BUT THE MARINE INFLUENCE SHOULD DIMINISH SOMEWHAT AND AFTERNOON TEMPERATURES WILL SHOW A WARMING TREND. && .AVIATION...02/2345Z AFTERNOON SEABREEZE CONTINUES TO BRING BROKEN CLOUDS TO A FEW LOCATIONS ALONG THE CENTRAL COAST AND OXNARD PLAIN COASTAL REGION. EXPECT A REPEAT PERFORMANCE FOR STRATUS AND PATCHY FOG ALONG THE COAST AND INTO THE VALLEY LOCATIONS OVERNIGHT. HIGH CONFIDENCE IN THIS SCENARIO AS MARINE LAYER HAS NOT CHANGED AND PLENTY OF ORGANIZED CLOUD COVER OFFSHORE. KLAX...PATCHY CLOUDS THROUGH 01-02Z BUT IFR CEILING LIKELY TO QUICKLY RETURN TOWARD SUNSET. 4-6SM HZ DEVELOPING DURING THE EVENING HOURS. KBUR...CLEAR SKIES AND TYPICAL VALLEY DRAINAGE WINDS THIS EVENING. EXPECT IFR CEILINGS AND FOG TO DEVELOP LATE TONIGHT. $$ .LOX WATCHES/WARNINGS/ADVISORIES... NONE && $$ PUBLIC...BOLDT/THOMPSON AVIATION...BOLDT WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS WICHITA KS
1155 PM CDT THU AUG 2 2007 .AVIATION... 06Z TAFS...DIURNAL COOLING COUPLED WITH VERY MOIST LOW-LEVELS AND LIGHT WINDS SHOULD PROMOTE MVFR VISIBILITIES TOWARD MORNING ACROSS THE AREA. OTHERWISE...MORE ISOLATED TO WIDELY SCATTERED SHOWERS/THUNDERSTORMS ANTICIPATED FOR FRIDAY AFTERNOON/EVENING...ESPECIALLY ACROSS EAST-CENTRAL/NORTHEAST KANSAS WHERE CONVERGENCE SHOULD BE GREATEST ALONG WEAK BOUNDARY. KLEINSASSER && .PREV DISCUSSION... /ISSUED 934 PM CDT THU AUG 2 2007/ UPDATE... PRECIPITATION WANED QUICKLY WITH SUNSET. HAVE NIXED THE FLASH FLOOD WATCH EARLY. FOCUS FOR REMAINDER OF NIGHT IS TWO-FOLD. ACARS DATA SHOWING WELL DEFINED RIPPLE MOVING ACROSS NORTHERN COLORADO AT THIS TIME. ANTICIPATE SOME STORMS WILL EITHER PERSIST OR DEVELOP ACROSS NORTHERN KS LATER TONIGHT AS THIS WAVE ROTATES AROUND UPPER RIDGE. HAVE KEPT HIGHEST PROBABILITY OF PRECIPITATION GOING AFTER MIDNIGHT TO ACCOUNT FOR THIS. SECOND AREA IS ALONG NORTHEASTERN EDGE OF FORECAST AREA WHERE BOTH GLOBAL FORECAST SYSTEM MODEL/NORTH AMERICAN MODEL SUGGEST MOISTENING/LIFT AT MIDDLE LEVELS WILL OCCUR DURING THE NIGHT. THIS BEING IN THE CLIMATOLOGICALLY FAVORED AREA/TIME OF DAY FOR ELEVATED CONVECTION...SEEMS PRUDENT TO KEEP SMALL PROBABILITY OF PRECIPITATION GOING AFTER MIDNIGHT. THIS SAME AREA APPEARS TO BE FAVORED AGAIN TOMORROW. IN ADDITION...COMPARISON OF 2100 UTC FORECAST SOUNDINGS FROM BOTH NORTH AMERICAN MODEL/GLOBAL FORECAST SYSTEM MODEL FOR ICT FOR THIS PAST AFTERNOON AND FRI AFTERNOON SHOW LITTLE DIFFERENCE...SO ISOLATED SO CALLED AIRMASS STORMS COULD DEVELOP ALMOST ANYWHERE AGAIN TOMORROW AFTERNOON. EXPANDED PROBABILITY OF PRECIPITATION VERY SLIGHTLY SW TO ACCOUNT FOR THIS. -HOWERTON AVIATION... COMBO OF MVFR OR BRIEF IFR HAZE/MIST WILL PLAGUE MOST SITES OVERNIGHT. HARD PRESSED TO NAIL DOWN THUNDERSTORM CHANCES... ALTHOUGH DID INCLUDED VCTS AT KCNU/KSLN FRI AFTERNOON WHERE CHANCES APPEAR TO BE HIGHEST. -HOWERTON PREV DISCUSSION... /ISSUED 248 PM CDT THU AUG 2 2007/ DISCUSSION... FORECAST CONCERNS... CONVECTIVE TRENDS/COVERAGE AND AMOUNTS THIS EVENING...THEN CHANCES THROUGH THE NEXT SEVEN DAYS... CONVECTION CONTINUES TO DEVELOP ALONG THE DIFFUSE SURFACE BOUNDARY ACROSS CENTRAL KANSAS. LOW LEVEL DEW POINT POOLING HAS RESULTED IN ML CAPES AROUND 2200 J/KG. WEAK CONVERGENCE SHOULD CONTINUE TO FOCUS BEST COVERAGE ACROSS CENTRAL KANSAS INTO THE EVENING...WITH SLOW MOVEMENT AND HIGH PRECIPITABLE WATER AGAIN PORTENDING TO SOME LOCALIZED PROLIFIC RAINFALL PRODUCERS. AS SUCH...INTER AND INTRA-OFFICE COLLABORATION SUPPORTED A FLASH FLOOD WATCH THROUGH THE EVENING FOR SEVERAL OF THE COUNTIES WITH ANTECEDENT WATER PROBLEMS OR RATHER LOW FFG VALUES FROM LAST NIGHTS HEAVY RAINFALL. WILL MAINTAIN SLIGHT CHANCES ALONG THE NORTHWARD MOVING SURFACE FRONT ON FRIDAY...MAINLY ACROSS THE NORTH AND EAST PERIPHERY OF THE FORECAST AREA. BEST FOCUS SHOULD SHIFT NORTH OF THE AREA INTO FRIDAY NIGHT/SATURDAY...IN CLOSER PROXIMITY TO AN UPPER SHORTWAVE WHICH TOPS THE RIDGE AND MOVES ACROSS THE MIDWEST. CHANCES FOR PRECIP WILL DIMINISH...THOUGH PERHAPS NOT TOTALLY END...ACROSS THE AREA INTO EARLY NEXT WEEK...AS THE UPPER RIDGE AXIS SHIFTS EAST ACROSS THE PLAINS. SLIGHTLY WARMER MID LEVEL TEMPERATURES AND SLIGHTLY LOWER SURFACE DEW POINTS WILL INCREASE THE CONVECTIVE INHIBITION ACROSS THE AREA. HOWEVER THE MODELS ARE NOT AS AGGRESSIVE AS IN PREVIOUS RUNS...WHICH WAS SOMEWHAT ANTICIPATED PER DISCUSSION ON NOTED MODEL BIAS YESTERDAY. SO WILL CONTINUE THE ISOLATED...MAINLY DIURNALLY DRIVEN...LATE AFTERNOON AND EVENING STORMS ACROSS THE AREA FROM SUNDAY THROUGH TUESDAY. WITH THE UPPER RIDGE AXIS TENDING TO BECOME MORE ELONGATED AND SOME TROFINESS DEVELOPING ALONG THE WEST COAST...PER ECM .A WEAK SOUTHWEST UPPER FLOW REGIME LOOKS TO DEVELOP INTO MID-WEEK. THIS WILL CONTINUE TO SUPPORT VERY WARM TEMPERATURES IN THE FORECAST...THOUGH AGAIN CANNOT RULE OUT DIURNAL/ISOLATED CONVECTION. THAT SAID...THE GFS IS A LITTLE MORE AGGRESSIVE WITH A POTENTIAL SHORTWAVE MOVING ACROSS THE NORTHERN PLAINS DURING THE TUESDAY/WEDNESDAY PERIODS...WHICH COULD PUSH ANOTHER FRONT INTO THE AREA. FORECAST CONSENSUS SUPPORTED TWEAKING POPS UP A BIT INTO THE SLIGHT CATEGORY DURING THESE PERIODS. DARMOFAL && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 92 71 93 72 / 40 20 10 10 HUTCHINSON 91 70 93 71 / 50 30 10 10 NEWTON 92 70 93 72 / 50 30 10 10 ELDORADO 92 70 93 71 / 40 20 10 10 WINFIELD-KWLD 93 70 93 72 / 20 10 10 10 RUSSELL 88 69 93 72 / 60 40 20 20 GREAT BEND 89 69 93 72 / 60 40 10 10 SALINA 89 70 93 72 / 50 30 20 20 MCPHERSON 90 70 93 71 / 50 30 10 10 COFFEYVILLE 92 69 93 71 / 20 10 10 10 CHANUTE 91 69 92 71 / 20 20 20 10 IOLA 91 69 92 71 / 40 20 20 10 PARSONS-KPPF 92 69 93 71 / 20 10 20 10 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
135 PM EDT FRI AUG 3 2007 .AVIATION (18Z TAFS)... STAGNANT AIRMASS WILL REMAIN IN PLACE WITH WINDS LESS THAN 5 KTS THROUGH 10K FT FOR THIS FORECAST PERIOD. THIS WILL HELP KEEP VSBYS IN THE IFR TO MVFR RANGE. ISOLATED THUNDERSTORMS WILL BE POSSIBLE LATE THIS AFTERNOON AND EVENING BUT I DON`T EXPECT ANY TO AFFECT THE TAF SITES. --JA && .LATE MORNING UPDATE... CURRENT FORECAST IS IN GOOD SHAPE SO I WILL MAKE ONLY COSMETIC ADJUSTMENTS WITH THE SKY CONDITION AND POPS. LATEST ACARS AND BUFKIT SOUNDINGS INDICATE A SLIGHTLY MORE STABLE ATMOSPHERE ACROSS THE WESTERN PORTION OF THE COUNTY FORECAST AREA WITH TEMPERATURES AROUND 5K FT A LITTLE WARMER THAN ACROSS THE EAST. WILL ADJUST POPS HIGHER IN THE EAST BUT WILL STILL KEEP POPS ACROSS ALL THE AREA IN THE ISOLATED CATEGORY. BUFKIT SOUNDINGS ALSO INDICATE VERY LIGHT WINDS THROUGH 10K FT SO ANY THUNDERSTORMS THAT DEVELOP WILL REMAIN NEARLY STATIONARY. --JA PREVIOUS DISCUSSION BELOW... .SHORT TERM (TODAY AND TONIGHT)... A VERY WEAK SURFACE TROF WILL SLIDE SOUTHEASTWARD TOWARDS THE OHIO RIVER TODAY...AND MEANDER ACROSS KENTUCKY TONIGHT. ALOFT...A WEAK VORT MAX WILL CROSS FROM SOUTHWEST INDIANA INTO WEST CENTRAL KENTUCKY LATE THIS AFTERNOON IN A SLIGHT WEAKNESS IN THE OTHERWISE STRONG UPPER RIDGE. WITH THE EXPECTED HOT TEMPERATURES PLUS DEW POINTS IN THE 60S THE ATMOSPHERE WILL BECOME SLIGHTLY UNSTABLE THIS AFTERNOON WITH LIFTED INDEX AROUND -4 AND CAPE AROUND 1000 J/KG. MODELS SHOW LITTLE IF ANY DEEP MOISTURE THIS AFTERNOON HOWEVER AND MOS POPS ACROSS THE BOARD ARE IN THE SINGLE DIGITS. NEVERTHELESS...GIVEN THAT WE HAD THUNDERSTORMS YESTERDAY AND OVERNIGHT WITH EVEN LESS OBVIOUS FORCING...FEEL IT IS NECESSARY TO INTRODUCE AT LEAST A SLIGHT CHANCE POP FOR THUNDERSTORMS THIS AFTERNOON GIVEN THE ABOVE FEATURES. THE BEST CHANCES FOR STORMS APPEAR TO BE ALONG THE OHIO RIVER AND IN THE BLUE GRASS. HIGHS TODAY WILL BE ABOUT THE SAME AS YESTERDAY. WITH DEW POINTS MIXING OUT A BIT THIS AFTERNOON HEAT INDEX READINGS SHOULD REMAIN IN THE 90S FOR THE BULK OF THE AFTERNOON. THANKS TO PAH...IND...AND JKL FOR COORDINATION. 13 .LONG TERM (SATURDAY THROUGH THURSDAY)... OVERALL...TO BE BLUNT ABOUT IT...THE ENTIRE EXTENDED FORECAST LOOKS HOT. SATURDAY AND SUNDAY... UPPER AIR PATTERN WILL BE PROGRESSIVE...BUT THE STORM TRACK WILL LIE IN ITS TYPICAL MID SUMMER POSITION ACROSS CANADA. A TROUGH ACROSS HUDSON BAY AND HIGH PRESSURE OVER THE GREAT LAKES WILL BRING TEMPORARILY COOLER TEMPERATURES AND LOWER DEWPOINTS SATURDAY AS FAR SOUTH AS NORTHERN INDIANA. HOWEVER...THE COLD FRONT RESPONSIBLE FOR THIS WILL HAVE WASHED OUT ACROSS CENTRAL INDIANA. NO RELIEF IS EXPECTED IN TEMPERATURES SATURDAY AND SUNDAY. BOTH THE GFS AND THE NAM SHOW A CONVECTIVE COMPLEX DEVELOPING SATURDAY ACROSS THE UPPER MIDWEST...AND TRACKING ACROSS NORTHERN INDIANA THROUGH EARLY SUNDAY ALONG THE REMNANTS OF A STATIONARY FRONT. IT IS POSSIBLE THAT SOME OUTFLOW RELATED BOUNDARY MAY MAKE IT AS FAR SOUTH AS SOUTHERN INDIANA EARLY SUNDAY. IN ADDITION...BOTH THE OPERATIONAL NAM AND GFS INCREASE MOISTURE SUNDAY AS LIGHT WESTERLY FLOW DEVELOPS. WILL INSERT A SLIGHT CHANCE OF POPS SUNDAY...ESPECIALLY ACROSS THE NORTH. MONDAY THROUGH THURSDAY... UPPER RIDGING INITIALLY ACROSS THE SOUTHERN PLAINS WILL STRENGTHEN AND EXPAND EASTWARD ACROSS THE OHIO VALLEY BY WEDNESDAY. BASED ON 500MB HEIGHTS AND FORECAST 925MB TEMPERATURES...MONDAY AND TUESDAY MAY EASILY WARM INTO THE UPPER 90S. SHOULD THIS HAPPEN...THESE WILL BECOME THE WARMEST HIGHS ACROSS CENTRAL KENTUCKY IN 2 YEARS. THE OPERATIONAL GFS FLATTENS THE RIDGE ACROSS THE EASTERN PART OF THE COUNTRY WEDNESDAY AND THURSDAY. HOWEVER THE ECWMF AND THE GFS ENSEMBLES ACTUALLY STRENGTHEN THE RIDGE...WHICH BY NOW IS FORECAST TO BE CENTERED ACROSS THE LOWER OHIO VALLEY. DO NOT EXPECT MUCH IF ANY COOLDOWN AROUND MID WEEK. PRECIPITATION CHANCES WILL BE MINIMAL MONDAY THROUGH WEDNESDAY. JSD && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. $$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1110 AM EDT FRI AUG 3 2007 .LATE MORNING UPDATE... CURRENT FORECAST IS IN GOOD SHAPE SO I WILL MAKE ONLY COSMETIC ADJUSTMENTS WITH THE SKY CONDITION AND POPS. LATEST ACARS AND BUFKIT SOUNDINGS INDICATE A SLIGHTLY MORE STABLE ATMOSPHERE ACROSS THE WESTERN PORTION OF THE COUNTY FORECAST AREA WITH TEMPERATURES AROUND 5K FT A LITTLE WARMER THAN ACROSS THE EAST. WILL ADJUST POPS HIGHER IN THE EAST BUT WILL STILL KEEP POPS ACROSS ALL THE AREA IN THE ISOLATED CATEGORY. BUFKIT SOUNDINGS ALSO INDICATE VERY LIGHT WINDS THROUGH 10K FT SO ANY THUNDERSTORMS THAT DEVELOP WILL REMAIN NEARLY STATIONARY. --JA PREVIOUS DISCUSSION BELOW... .SHORT TERM (TODAY AND TONIGHT)... A VERY WEAK SURFACE TROF WILL SLIDE SOUTHEASTWARD TOWARDS THE OHIO RIVER TODAY...AND MEANDER ACROSS KENTUCKY TONIGHT. ALOFT...A WEAK VORT MAX WILL CROSS FROM SOUTHWEST INDIANA INTO WEST CENTRAL KENTUCKY LATE THIS AFTERNOON IN A SLIGHT WEAKNESS IN THE OTHERWISE STRONG UPPER RIDGE. WITH THE EXPECTED HOT TEMPERATURES PLUS DEW POINTS IN THE 60S THE ATMOSPHERE WILL BECOME SLIGHTLY UNSTABLE THIS AFTERNOON WITH LIFTED INDEX AROUND -4 AND CAPE AROUND 1000 J/KG. MODELS SHOW LITTLE IF ANY DEEP MOISTURE THIS AFTERNOON HOWEVER AND MOS POPS ACROSS THE BOARD ARE IN THE SINGLE DIGITS. NEVERTHELESS...GIVEN THAT WE HAD THUNDERSTORMS YESTERDAY AND OVERNIGHT WITH EVEN LESS OBVIOUS FORCING...FEEL IT IS NECESSARY TO INTRODUCE AT LEAST A SLIGHT CHANCE POP FOR THUNDERSTORMS THIS AFTERNOON GIVEN THE ABOVE FEATURES. THE BEST CHANCES FOR STORMS APPEAR TO BE ALONG THE OHIO RIVER AND IN THE BLUE GRASS. HIGHS TODAY WILL BE ABOUT THE SAME AS YESTERDAY. WITH DEW POINTS MIXING OUT A BIT THIS AFTERNOON HEAT INDEX READINGS SHOULD REMAIN IN THE 90S FOR THE BULK OF THE AFTERNOON. THANKS TO PAH...IND...AND JKL FOR COORDINATION. 13 .LONG TERM (SATURDAY THROUGH THURSDAY)... OVERALL...TO BE BLUNT ABOUT IT...THE ENTIRE EXTENDED FORECAST LOOKS HOT. SATURDAY AND SUNDAY... UPPER AIR PATTERN WILL BE PROGRESSIVE...BUT THE STORM TRACK WILL LIE IN ITS TYPICAL MID SUMMER POSITION ACROSS CANADA. A TROUGH ACROSS HUDSON BAY AND HIGH PRESSURE OVER THE GREAT LAKES WILL BRING TEMPORARILY COOLER TEMPERATURES AND LOWER DEWPOINTS SATURDAY AS FAR SOUTH AS NORTHERN INDIANA. HOWEVER...THE COLD FRONT RESPONSIBLE FOR THIS WILL HAVE WASHED OUT ACROSS CENTRAL INDIANA. NO RELIEF IS EXPECTED IN TEMPERATURES SATURDAY AND SUNDAY. BOTH THE GFS AND THE NAM SHOW A CONVECTIVE COMPLEX DEVELOPING SATURDAY ACROSS THE UPPER MIDWEST...AND TRACKING ACROSS NORTHERN INDIANA THROUGH EARLY SUNDAY ALONG THE REMNANTS OF A STATIONARY FRONT. IT IS POSSIBLE THAT SOME OUTFLOW RELATED BOUNDARY MAY MAKE IT AS FAR SOUTH AS SOUTHERN INDIANA EARLY SUNDAY. IN ADDITION...BOTH THE OPERATIONAL NAM AND GFS INCREASE MOISTURE SUNDAY AS LIGHT WESTERLY FLOW DEVELOPS. WILL INSERT A SLIGHT CHANCE OF POPS SUNDAY...ESPECIALLY ACROSS THE NORTH. MONDAY THROUGH THURSDAY... UPPER RIDGING INITIALLY ACROSS THE SOUTHERN PLAINS WILL STRENGTHEN AND EXPAND EASTWARD ACROSS THE OHIO VALLEY BY WEDNESDAY. BASED ON 500MB HEIGHTS AND FORECAST 925MB TEMPERATURES...MONDAY AND TUESDAY MAY EASILY WARM INTO THE UPPER 90S. SHOULD THIS HAPPEN...THESE WILL BECOME THE WARMEST HIGHS ACROSS CENTRAL KENTUCKY IN 2 YEARS. THE OPERATIONAL GFS FLATTENS THE RIDGE ACROSS THE EASTERN PART OF THE COUNTRY WEDNESDAY AND THURSDAY. HOWEVER THE ECWMF AND THE GFS ENSEMBLES ACTUALLY STRENGTHEN THE RIDGE...WHICH BY NOW IS FORECAST TO BE CENTERED ACROSS THE LOWER OHIO VALLEY. DO NOT EXPECT MUCH IF ANY COOLDOWN AROUND MID WEEK. PRECIPITATION CHANCES WILL BE MINIMAL MONDAY THROUGH WEDNESDAY. JSD && .AVIATION (12Z TAFS)... ONCE AGAIN WE WILL BE DEALING WITH MVFR HAZE...POSSIBLY BRIEFLY HIGH END IFR...AT THE TAF SITES AROUND DAWN. SDF STRUGGLED TO GET TO VFR CONDITIONS YESTERDAY AND WILL LIKELY BE ON THE CUSP OF MVFR/VFR ONCE AGAIN TODAY. ISOLATED STORMS ARE ON-GOING AT THIS TIME AND FURTHER ISOLATED STORMS WILL BE POSSIBLE LATER TODAY AND THIS EVENING BUT COVERAGE IS TOO SMALL TO INCLUDE AT THE TAFS AT THIS TIME...UNFORTUNATELY MAY NEED TO WAIT UNTIL WE SEE THE WHITES OF THEIR EYES AND ISSUE AMENDMENTS IF A LONE STORM HAPPENS TO FORM NEAR A TAF SITE. 13 && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. $$
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
940 PM EDT SAT AUG 4 2007 .UPDATE... STUBBORN ISOLD CONVECTION IN SWRN ZONES HOLDING ON. WILL KEEP IN FCST OVERNIGHT...THOUGH SINCE ATMOSPHERE IS STABILIZING...IT SHD DISSIPATE. OTRW...DRY FCST FOR TNGT AND NO OTHER CHGS PLANNED. && .SYNOPSIS... A WEAK FRONTAL BOUNDARY ACROSS THE REGION THIS EVENING WILL STALL OVER CENTRAL VIRGINIA OVERNIGHT. ON SUNDAY THE REMAINS OF A THUNDERSTORM COMPLEX OVER THE UPPER MID WEST WILL AFFECT THE REGION. WEAK HIGH PRESSURE FEATURING HOT AND HUMID CONDITIONS WILL AFFECT THE REGION FOR THE COMING WORK WEEK. LITTLE ORGANIZED PRECIPITATION IS EXPECTED FOR THE UPCOMING WEEK...OTHER THAN ISOLATED TO SCATTERED THUNDERSTORMS. HEAT INDEX VALUES COULD TOP 100 ON TUE AND WED. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... WATER VAPOR LOOP SHOWS SUBSIDENCE OVER THE MID ATLANTIC BEHIND A TROUGH. A MCV IS MOVING EAST ACROSS THE MIDWEST. ACARS 400-250MB WIND OBSERVATIONS REVEAL THE POSITION OF THE UPPER LEVEL TROUGH IS ALONG THE EAST COAST. A 80-100KT SOUTHWESTERLY JET EXTENDS FROM THE WEST COAST THROUGH THE GREAT LAKES. 11Z SURFACE ANALYSIS PLACE A WEST TO EAST WARM FRONT LIFTING NORTH ACROSS THE GULF STATES. A COLD FRONT ENTERING NEW ENGLAND IS STALLING ACROSS THE MIDWEST...WITH THE PRE-FRONTAL TROUGH POSITIONED FROM CENTRAL VIRGINIA NORTHEAST ALONG INTERSTATE 95. A 1021MB ANTICYCLONE DOMINATED THE GREAT LAKES. SATELLITE AND GPS PRECIPITABLE WATER SENSORS INDICATE DEEP LAYER MOISTURE IS FALLING ACROSS THE REGION...EVEN AHEAD OF THE COLD FRONT. BEST MOISTURE IS BEING RETAINED ALONG AND EAST OF INTERSTATE 95...COINCIDENT WITH THE POSITION OF THE PRE-FRONTAL TROUGH. THIS IS WHERE THE BEST CHANCE OF CONVECTION WILL BE...AS ALSO SHOWN BY SIMULATED REFLECTIVITY FROM THE NCEP WRF-NMM AND NSSL WRF-ARW. ADJUSTED 12Z KIAD RAOB DOES INDICATE MODERATE INSTABILITY WILL BE PRESENT...AND WITH SUCH A DRY SOUNDING A LOCAL DAMAGING WIND GUST CANNOT BE RULED OUT. SENSITIVE GROUPS MAY FEEL THE IMPACT OF THE HEAT LATE THIS AFTERNOON...MENTION WILL REMAIN IN THE HAZARDOUS WEATHER OUTLOOK. CONVECTION SHOULD WIND DOWN QUICKLY ACROSS THE SOUTHEAST ZONES WITH THE LOSS OF HEATING. WHILE CONVECTIVE CLOUDINESS WILL WANE...EXPECT MID AND UPPER LEVEL MOISTURE TO APPROACH FROM THE NORTHWEST LATE DURING THE NIGHT...AHEAD OF A CONVECTIVE COMPLEX. BASED ON RECENT PERFORMANCE...USED THE 12Z MET GUIDANCE FOR LOW TEMPERATURES WHICH WAS ADJUSTED LOCALLY FOR BIAS. WINDS WERE BASED ON THE LWX 4KM WRF-ARW. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... MCV FROM THE GREAT LAKES EXPECTED TO IMPACT FORECAST AREA SUNDAY...ESPECIALLY BY THE MID AFTERNOON ACROSS THE EASTERN ZONES. BASED ON TIMING...HIGHEST POPS ARE ACROSS WESTERN ZONES. BEST CHANCE TO SEE PARTIAL SUNSHINE WILL BE ACROSS THE SOUTHERN ZONES. IF SYSTEM BREAKS DOWN FASTER THAN ANTICIPATED...GREATER BREAKS IN CLOUDS WOULD ALLOW FOR GREATER AFTERNOON DESTABILIZATION. GIVEN NORTHWEST FLOW...A FEW STORMS WOULD THEN BE STRONG OR SEVERE. HIGHS ARE TRICKY...DUE TO CLOUD FORECAST AND NORTHEAST FLOW OFF THE OCEAN. WENT WITH GFS MOS HIGHS DUE TO RECENT PERFORMANCE AND LOWER GUIDANCE NUMBERS. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THE LONG TERM WILL FEATURE ABOVE NORMAL TEMPERATURES AS A BROAD FLAT SUB-TROPICAL RIDGE SETS UP ACROSS THE SOUTHEAST AND EXTENDING WEST INTO THE SOUTHERN PLAINS. ABOVE TO MUCH ABOVE NORMAL PRECIP WATER VALUES ARE EXPECTED MAKING THE PERIOD FAIRLY HUMID. THE WARMEST DAYS WILL LIKELY BE TUE AND WED...WITH SOME READINGS ON WED APPROACHING THE UPPER 90S TO NEAR 100. RAINFALL CHANCES WILL BE DEPENDENT MAINLY ON ANY WEAK FEATURES THAT MANAGE TO MOVE BETWEEN THE NORTHERN PERIPERHY OF THE RIDGE AND THE UPPER LEVEL LOW PRES VORTEX OVER THE HUDSON BAY REGION. WOULD EXPECT TO SEE SOME DAILY LATE AFTERNOON/OVERNIGHT MCS ACTIVITY ACROSS THE NORTHERN PLAINS...GREAT LAKES INTO NEW ENGLAND THROUGH MUCH OF THE WEEK. HENCE RAIN CHANCES WILL BE DUE TO LESS ORGANIZED SYSTEMS THAT FIRE DUE TO LOCAL/MESOSCALE WIND CIRCULATIONS...E.G. BAY BREEZE AND MOUNTAIN-VALLEY. SOME SLIGHT LOWERING OF UPPER LEVEL HEIGHTS LATE IN THE WEEK SUGGESTS A SLIGHT COOLING OF THE AIRMASS...PERHAPS DUE TO A WEAK FRONTAL SYSTEM THE ENSEMBLES ADVERTIZE FOR LATE IN THE WEEK. BUT SURFACE HIGH PRESSURE NOT VERY STRONG ACROSS THE GREAT LAKES...NEED AT LEAST 1020 HPA HIGH CENTERS OVER THIS REGION TO PUSH A FRONT DOWN INTO OUR REGION DURING MID-SUMMER AND DO NOT SEE THAT HAPPENING. HENCE RAINFALL WILL BE SCATTERED AT BEST...MAYBE A FEW LUCKY SPOTS RECEIVE CONVECTIVE RAINS...BUT MOST PLACES WILL REMAIN BONE DRY. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... PROBABILITY FOR ISOLATED STORM TO AFFECT TERMINALS TOO REMOTE TO MENTION IN TAFS AT THIS TIME. DRIER AIR WORKS IN FROM THE NORTH WITH AN EVENING FRONTAL PASSAGE. THINK VISIBILITIES WILL IMPROVE TO P6SM WITH COLD FRONTAL PASSAGE...EXCEPT NEAR CHO WHERE FRONT STALLS LATE TONIGHT. INCREASING MID AND UPPER CLOUDS TONIGHT WITH THE NEXT SYSTEM AFFECTS THE REGION SUNDAY INTO SUNDAY NIGHT. LOCALLY REDUCED VISIBILITIES/CEILINGS...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE NEAR THUNDERSTORMS. MON THROUGH THU EXPECT MOSTLY VFR WITH SOME MVFR IN HAZE AND POSSIBLE IFR AT IAD/CHO/MRB DURING EARLY MORNING HRS DUE TO PRE- DAWN FOG. ISOLATED TSTM ACTIVITY DURING THE MID TO LATE AFTERNOON HOURS AS WELL. && .MARINE... WINDS AROUND 10KT THROUGH TOMORROW AS DICTATED BY VALID MOS GUIDANCE AND LWX WRF-ARW. SCATTERED THUNDERSTORMS EXPECTED THIS AFTERNOON AND EVENING...AHEAD OF THE NEXT SYSTEM WHICH AFFECTS THE REGION SUNDAY. WINDS AND WAVES WILL BE HIGHER NEAR STORMS. LOCALLY REDUCED VISIBILITIES AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE. FOR THE EXTENDED PERIOD...EXPECT TYIPICAL SUMMERTIME PATTERN TO THE WINDS AS THE BERMUDA HIGH REMAINS OFF THE SE U.S. COAST. ON THE BAY EXPECT SOME LATE AFTERNOON/EARLY EVENING CHANNELLING OF SOUTHERLY WINDS ACROSS THE MIDDLE AND LOWER BAY COULD GIVE GUSTS TO SCA LEVELS AT TIMES. OTHER THAN ISOLATED AFTERNOON/EVENING TSTMS...EXPECT MAINLY DRY WEATHER FOR THE COMING WEEK. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...SJR NEAR TERM...RDH SHORT TERM...SJR LONG TERM...SMZ AVIATION...SJR MARINE...SJR/SMZ
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
232 PM EDT FRI AUG 3 2007 .SYNOPSIS... SCATTERED THUNDERSTORMS AREAWIDE THIS AFTERNOON AND EVENING AS A MID LEVEL DISTURBANCE PASSES OVERHEAD. CONTINUED WARM TEMPS SATURDAY AS A WEAK FRONT PUSHES SOUTH OF THE AREA. SHOWERS AND THUNDERSTORMS RIDING THE FRONT FROM THE GREAT LAKES MAY AFFECT THE REGION SUNDAY. THIS FRONT WILL LIFT NORTHEAST AS A WARM FRONT BY MONDAY WITH HEAT AND HUMIDITY RETURNING FOR NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... WATER VAPOR LOOP SHOWS AN UPPER TROUGH MOVING THROUGH THE OHIO VALLEY. ACARS 400-250MB OBSERVATIONS ALSO SHOW THE UPPER LEVEL TROUGH...WITH A 50-70KT SOUTHWESTERLY JET FROM THE EASTERN GULF STATES THROUGH THE CAROLINAS. 11Z SURFACE ANALYSIS PLACED THE NEXT COLD FRONT SOUTHWEST ACROSS THE GREAT LAKES AND CHICAGOLAND...TO A 1016MB CYCLONE NEAR ST LOUIS. A PRE-FRONTAL TROUGH WAS EVIDENT...COINCIDING WITH THE UPPER TROUGH OVER THE OHIO VALLEY. EARLY MORNING CONVECTION IN THE APPALACHIANS INDICATES AMOUNT OF MID LEVEL INSTABILITY AVAILABLE TODAY. ADJUSTED 12Z KIAD RAOB INDICATES ABOUT 1200 J/KG MIXED LAYER CAPE. WHEN COMBINED WITH WEAK BOUNDARY LAYER FLOW...THIS IS MORE THAN ENOUGH ENERGY FOR SOLENOIDAL CIRCULATION TERRAIN STORM DEVELOPMENT. IN ADDITION...WILL HAVE TO MONITOR THE PASSAGE OF THE MID LEVEL TROUGH LATE THIS AFTERNOON AS THIS MAY TRIGGER ADDITIONAL DEVELOPMENT AND AID IN STORM ORGANIZATION. WITH WARM TEMPERATURES ALOFT...THE DRY SOUNDING SUGGESTS GREATEST STORM RISK IS LOCALLY DAMAGING WINDS. GIVEN SLOW STORM MOVEMENT...A FEW LOCATIONS COULD SEE LOCALLY HEAVY RAINFALL. OTHER CONSIDERATION IS THE AFTERNOON HEAT. HIGHS ARE BASED ON YESTERDAY (GIVEN NEARLY ZERO ADVECTION). DEWPOINTS SHOULD LEVEL OFF OR SLOWLY DECLINE THIS AFTERNOON. THIS COMBINES TO PRODUCE HEAT INDEX VALUES NEARING 100F. WILL AGAIN HIGHLIGHT IN HWO AS IS LOOKS JUST SHY OF ADVISORY CRITERIA IN THE CITIES. BEST CONVECTIVE COVERAGE EXPECTED THIS EVENING COINCIDENT WITH PASSAGE OF MID LEVEL TROUGH. DID ADJUST POPS TO INDICATE BEST COVERAGE EAST OF THE BLUE RIDGE BASED ON THE TIMING OF THIS FEATURE. WILL HAVE TO MONITOR FOR A FEW STRONG TO SEVERE STORMS. EXPECT TO CLEAR OUT BEHIND THE TROUGH. WITH DEWPOINTS EXPECTED TO SLOWLY CLIMB THERE COULD BE SOME AREAS OF LIGHT FOG...MORE CONCENTRATED IN SHELTERED VALLEYS WHICH RECEIVE RAINFALL. LOWS ARE BASED ON MET GUIDANCE WHICH HAS BEEN PREFORMING WELL RECENTLY...ADJUSTED FOR LOCAL BIAS. WIND FORECAST IS BASED ON THE 12Z 4KM WRF-ARW. && .SHORT TERM /SATURDAY/... MID LEVEL TROUGH PASSES TO THE EAST TOMORROW...WITH SUBSIDENCE SUPPORTING EARLY SUNSHINE. A FEW STORMS WILL BE POSSIBLE...ESPECIALLY IN THE PIEDMONT AS THE COLD FRONT MOVES SOUTH INTO MARYLAND LATE DURING THE AFTERNOON. WITH SLIGHTLY LESS MOISTURE AND ADDED SUBSIDENCE...FORECAST MAX TEMPERATURES ARE SEVERAL DEGREES WARMER THAN TODAY. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... EC/GFS MODELS/ENSEMBLES CONTINUE TO BE IN GOOD AGREEMENT WITH OVERALL PATTERN. MAIN WEATHER FEATURES AFFECTING THE U.S. OVER THE NEXT WEEK WILL BE A BROAD TROF ACROSS THE WEST COAST WHILE A FLAT UPPER RIDGE WILL PREVAIL ACROSS THE EASTERN THIRD OF THE COUNTRY. WESTERLIES WILL MIGRATE NORTH ACROSS THE CANADIAN BORDER BUT PERIODICALLY DIP INTO THE GREAT LAKES AREA FOR THE UPCOMING WEEK. AS A RESULT...THIS WILL ALLOW WEAK FRONTS TO MIGRATE INTO OR JUST NORTH OF THE AREA THROUGH FRIDAY. STATIONARY FRONTAL BOUNDARY ACROSS AREA WILL BE THE FOCUS MECHANISM FOR A WEAKENING MCS SLIDING EASTWARD INTO AREA FOR SUNDAY AFTERNOON/NIGHT. GFS HAS BEEN ADVERTISING THIS FOR SEVERAL DAYS SO HIGH CHANCE POPS SHOULD SUFFICE. A SECOND...BACKDOOR FRONT...FORECAST TO SLIDE SOUTH ACROSS CWA LATE MONDAY AND STALL ACROSS SOUTHEAST ZONES. ANOTHER WAVE SLIDING BY TO OUR NORTH SHOULD GIVE THE STALLED FRONT A KICK SOUTH OF THE REGION BY FRIDAY. GIVEN THE ABOVE...WILL NEED TO HAVE A MENTION OF DIURNAL CHANCE/SLIGHT POPS IN EXTENDED FORECAST EACH DAY. ABOVE NORMAL TEMPERATURES WILL CONTINUE THROUGH THE PERIOD. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... ISOLATED LATE AFTERNOON CONVECTION SHOULD STRENGTHEN AND INCREASE IN COVERAGE EARLY THIS EVENING WITH ARRIVAL OF MID LEVEL TROUGH. PATCHY LIGHT FOG EXPECTED ACROSS RURAL SITES...WHICH MAY BECOME LOCALLY DENSE IF RAINFALL OCCURS. MORE ISOLATED CONVECTION SATURDAY. SCATTERED STORMS EXPECTED SUNDAY AFTERNOON/EVENING...MORE ISOLATED AFTERNOON AND EVENING STORMS FORECAST FOR THE REST OF THE WEEK. WINDS WILL BE HIGHER NEAR STORMS. LOCALLY REDUCED VISIBILITIES AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE. && .MARINE... SOUTHERLY WINDS EXPECTED TO CHANNEL TO NEAR SMALL CRAFT CRITERIA THIS EVENING ACROSS THE BAY AND LOWER POTOMAC (BASED ON 12Z GFS/ETA MOS AND 12Z WRF-LWX). SCATTERED STORMS THIS EVENING...MORE ISOLATED SATURDAY. SCATTERED STORMS EXPECTED SUNDAY AFTERNOON/EVENING...ISOLATED AFTERNOON/EVENING STORMS FORECAST FOR THE REST OF THE WEEK. WINDS AND WAVES WILL BE HIGHER NEAR STORMS. LOCALLY REDUCED VISIBILITIES AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...ROGOWSKI NEAR TERM...ROGOWSKI SHORT TERM...ROGOWSKI LONG TERM...RW AVIATION...ROGOWSKI/RW MARINE...ROGOWSKI/RW
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1034 AM EDT FRI AUG 3 2007 .SYNOPSIS... WIDELY SCATTERED THUNDERSTORMS AREAWIDE THIS AFTERNOON AS A MID LEVEL DISTURBANCE PASSES OVERHEAD. CONTINUED WARM TEMPS SATURDAY AS A WEAK FRONT PUSHES SOUTH OF THE AREA. SHOWERS AND THUNDERSTORMS RIDING THE FRONT FROM THE GREAT LAKES MAY AFFECT THE REGION SUNDAY. THIS FRONT WILL LIFT NORTHEAST AS A WARM FRONT BY MONDAY WITH HEAT AND HUMIDITY RETURNING FOR NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WATER VAPOR LOOP SHOWS AN UPPER TROUGH MOVING THROUGH THE OHIO VALLEY. ACARS 400-250MB OBSERVATIONS ALSO SHOW THE UPPER LEVEL TROUGH...WITH A 50-70KT SOUTHWESTERLY JET FROM THE EASTERN GULF STATES THROUGH THE CAROLINAS. 11Z SURFACE ANALYSIS PLACED THE NEXT COLD FRONT SOUTHWEST ACROSS THE GREAT LAKES AND CHICAGOLAND...TO A 1016MB CYCLONE NEAR ST LOUIS. A PRE-FRONTAL TROUGH WAS EVIDENT...COINCIDING WITH THE UPPER TROUGH OVER THE OHIO VALLEY. EARLY MORNING CONVECTION IN THE APPALACHIANS INDICATES AMOUNT OF MID LEVEL INSTABILITY AVAILABLE TODAY. ADJUSTED 12Z KIAD RAOB INDICATES ABOUT 1200 J/KG MIXED LAYER CAPE. WHEN COMBINED WITH WEAK BOUNDARY LAYER FLOW...THIS IS MORE THAN ENOUGH ENERGY FOR SOLENOIDAL CIRCULATION TERRAIN STORM DEVELOPMENT. IN ADDITION...WILL HAVE TO MONITOR THE PASSAGE OF THE MID LEVEL TROUGH LATE THIS AFTERNOON AS THIS MAY TRIGGER ADDITIONAL DEVELOPMENT AND AID IN STORM ORGANIZATION. WITH WARM TEMPERATURES ALOFT...THE DRY SOUNDING SUGGESTS GREATEST STORM RISK IS LOCALLY DAMAGING WINDS. GIVEN SLOW STORM MOVEMENT...A FEW LOCATIONS COULD SEE LOCALLY HEAVY RAINFALL. 06Z GFS IS RATHER DRY AND THE 06Z NAM IS ON THE WET SIDE. 4KM NCEP WRF-NMM SIMULATED REFLECTIVITY SIDES WITH THE NAM WHILE THE 4KM NSSL WRF-ARW IS MORE RESTRAINED. USED A COMPROMISE SOLUTION FOR POP COVERAGE. OTHER CONSIDERATION IS THE AFTERNOON HEAT. HIGHS ARE BASED ON YESTERDAY (GIVEN NEARLY ZERO ADVECTION). DEWPOINTS SHOULD LEVEL OFF OR SLOWLY DECLINE THIS AFTERNOON. THIS COMBINES TO PRODUCE HEAT INDEX VALUES NEARING 100F. WILL AGAIN HIGHLIGHT IN HWO AS IS LOOKS JUST SHY OF ADVISORY CRITERIA IN THE CITIES. WIND FORECAST IS BASED ON THE 06Z 4KM WRF-ARW. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... BEST CONVECTIVE COVERAGE EXPECTED THIS EVENING COINCIDENT WITH PASSAGE OF MID LEVEL TROUGH. DID ADJUST POPS TO INDICATE BEST COVERAGE EAST OF THE BLUE RIDGE BASED ON THE TIMING OF THIS FEATURE. WILL HAVE TO MONITOR FOR A FEW STRONG TO SEVERE STORMS. EXPECT TO CLEAR OUT BEHIND THE TROUGH. WITH DEWPOINTS EXPECTED TO SLOWLY CLIMB THERE COULD BE SOME AREAS OF FOG. WILL ADDRESS THIS WITH THE NEXT UPDATE. && .LONG TERM /SATURDAY THROUGH THURSDAY/... WEAK FRONT WILL APPROACH THE AREA FROM THE NW ON SAT AND STALL ACROSS THE AREA ON SUN. ISOLD TSTMS POSSIBLE SAT AFTERNOON MAINLY ERN ZONES AND THE BAY. ON SUN...GFS MOST AGGRESSIVE MODEL INDICATING A CONVECTIVE COMPLEX WILL TRAVEL ESEWD FROM THE MIDWEST ACROSS THE NRN HALF OF FCST AREA. STILL LOW CONFIDENCE FCST ON THIS SCENARIO BUT WILL MAINTAIN CONTINUITY. FRONT LIFTS NORTHEAST OF THE AREA MON AS A WARM FRONT WITH HEAT BUILDING BACK. && .AVIATION /14Z FRIDAY THROUGH TUESDAY/... WHILE THERE SHOULD BE ISOALTED TO SCATTERED CONVECTION...IT IS TOUGH TO PLACE AT THIS TIME. 12Z TAFS MENTION A CB GROUP...AND ANTICIPATING KEEPING THIS FOR THE 18Z TAFS. OF COURSE...LATER SATELLITE/RADAR OBSERVATIONS WILL BE USED TO TRY TO TIME ANY CONVECTION WHICH MAY DEVELOP DURING THE MIDDAY. MORE ISOLATED CONVECTION SATURDAY...BEFORE THE NEXT SYSTEM AFFECTS THE REGION SUNDAY. LOCALLY REDUCED VISIBILITIES/CEILINGS...GUSTY WINDS AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE. && .MARINE... SOUTHERLY WINDS EXPECTED TO CHANNEL TO NEAR SMALL CRAFT CRITERIA THIS EVENING ACROSS THE BAY AND LOWER POTOMAC (BASED ON 06Z GFS/00Z ETA MOS AND 09Z WRF-LWX). SCATTERED STORMS THIS EVENING...MORE ISOLATED SATURDAY BEFORE THE NEXT STORM SYSTEM AFFECTS THE REGION SUNDAY. WINDS AND WAVES WILL BE HIGHER NEAR STORMS. LOCALLY REDUCED VISIBILITIES AND CLOUD TO GROUND LIGHTNING WILL BE POSSIBLE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...ROGOWSKI NEAR TERM...ROGOWSKI SHORT TERM...ROGOWSKI LONG TERM...ROSA AVIATION...ROGOWSKI/ROSA MARINE...ROGOWSKI/ROSA
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
834 PM EDT SAT AUG 4 2007 LATEST UPDATE...SHORT TERM... .SYNOPSIS... (340 PM EDT SAT AUG 4 2007) A LOW PRESSURE SYSTEM OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS SOUTHERN LOWER MICHIGAN BY SUNDAY EVENING. AHEAD OF THIS SYSTEM... SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS LAKE MICHIGAN INTO SOUTHWEST LOWER MICHIGAN SUNDAY MORNING. DUE TO ABUNDANT MOISTURE LOCALLY HEAVY RAIN WILL BE POSSIBLE. && .SHORT TERM... (834 PM EDT SAT AUG 4 2007) LATEST REGIONAL RADAR IMAGERY SHOWS A BAND OF MAINLY SHOWERS EXTENDING FROM NORTH OF KLSE...DOWN THROUGH KORD...AND THEN DOWN INTO EAST CENTRAL IL AND WEST CENTRAL IN. THIS PCPN IS CLOSELY ASSOCIATED WITH A STRONG BAND OF MID LEVEL THETA E ADVECTION. THE PCPN WILL CONTINUE ESE WHILE THE ENTIRE BAND SHIFTS SLOWLY EAST. PCPN DOES CONTINUE TO DRY UP AS IT MOVES TOWARD THE AREA WITH PLENTY OF LOW LEVEL DRY AIR IN PLACE...BUT SOME OF THE HEAVIER SHOWERS SHOULD BE ABLE TO REACH THE SW CORNER OF THE CWFA WHERE THE DEEPER MOISTURE IS LOCATED. WE EXPECT THAT A BIT MORE WIDESPREAD PCPN WILL BEGIN REACHING THE GROUND OVER THE SW CORNER OF THE CWFA TOWARD/AFTER MIDNIGHT TONIGHT. WITH THIS IN MIND...WE HAVE INCREASED POPS UP INTO THE NUMEROUS/LIKELY CATEGORY. THE SECOND AREA OF PCPN WE ARE WATCHING IS AN AREA OF SCT SHOWERS AND STORMS DEVELOPING OVER NRN IA AND SRN MN AT THE NOSE OF THE STRENGTHENING LLJ. WE EXPECT THIS IS THE AREA OF PCPN THAT WILL BEGIN TO APPROACH THE AREA TOWARD DAYBREAK AND SUN MORNING AS THE LLJ SHIFTS INTO THE AREA. LIGHTNING IS BEING OBSERVED OUT THERE...IN AN AREA WHERE ELEVATED LI/S BASED AROUND 750 MB ARE 0 TO -2C. MODELS SHIFT THIS POOL OF INSTABILITY ALOFT OVER THE AREA ALONG AND SOUTH OF INTERSTATE 96 BY 12Z SUN. WE HAVE ADDED A MENTION OF ISOLATED THUNDER INTO THE FCST FOR THE SRN HALF OF THE CWFA FOR AFTER MIDNIGHT. TONIGHT THROUGH MONDAY - MAIN CONCERN IS QPF SUNDAY. GFS QPF SOLUTION IS CONSIDERABLY FARTHER S THAN NAM AND SREF SOLUTION...AND IS STRONGLY FAVORED BY HPC. GFS SOLUTION IS CLOSER TO THE SURFACE BOUNDARY THAT EXTENDED THROUGH NRN IL AND CENTRAL AT 17Z. UPSTREAM CONVECTION HAS BEEN ELEVATED AND WE EXPECT THIS TO BE THE CASE AGAIN OVERNIGHT. THUS...THE QPF MAXIMUM COULD BE FAR REMOVED FROM THE SURFACE BOUNDARY. CURRENT TRENDS APPEAR TO SUPPORT THE FARTHER NORTH NAM SOLUTION FOR HIGHER QPF. AFTER DISCUSSION WITH SURROUNDING OFFICES...HAVE DECIDED TO TAKE A BLEND OF GFS...NAM...AND OUR LOCAL WRF. OUR LOCAL WRF IS MOST AGGRESSIVE BY DROPPING AN AXIS OF 2+" PRECIP ALONG A HOLLAND-JACKSON LINE. THIS AXIS IS BETWEEN THE AXES OF THE NAM AND GFS SOLUTIONS. AT THIS POINT WE ARE NOT TOO CONCERNED ABOUT FLOODING...AS THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BASED ON MEAN WIND ORIENTATION. LATEST FORECAST SOUNDINGS ALSO SUGGEST A SHALLOWER WARM CLOUD DEPTH COMPARED TO EARLIER RUNS. LOCAL NUISANCE FLOODING CERTAINLY WILL BE POSSIBLE...ESPECIALLY SINCE SOIL IS BAKED AND QUITE IMPERMEABLE. WILL UPDATE THE HWO TO MENTION THIS. NEXT CONCERN IS STRONG/SEVERE CONVECTION SUNDAY AFTERNOON. THE SPC DAY2 OUTLOOK ISSUED AT 1730Z INCLUDED FAR SW LOWER MI IN A SLIGHT RISK. AT THIS POINT WE ARE NOT TOO CONCERNED...AS WE EXPECT MARGINAL INSTABILITY AND LIMITED INSOLATION DUE TO SIGNIFICANT CLOUDS. && .LONG TERM...(140 PM EDT SAT AUG 4 2007) THE SREF MEAN AS WELL AS GFS AND CANADIAN GUIDANCE SUGGESTS THAT ANOTHER MCS COULD POTENTIALLY AFFECT OUR CWFA TOWARDS DAYBREAK TUESDAY. HOWEVER THE GFS IS SUFFERING FROM SIGNIFICANT CONVECTIVE FEEDBACK ISSUES WHICH ARE EVIDENT IN THE STABLE VERSUS CONVECTIVE QPF AND UPPER LEVEL HEIGHT/VORT FIELDS AS WELL SPURIOUS EXCESSIVE QPF BULLSEYE. BASED ON CONF CALL COORDINATION WITH APX/DTX/IWX WE WILL ONLY MENTION A SLIGHT CHC OF CONVECTION LATE MONDAY NIGHT. THE BETTER CHANCE FOR RAIN AND CONVECTION WILL HOLD OFF UNTIL TUESDAY WITH GUIDANCE SUGGESTING A STRONGER LOW PRESSURE WAVE WILL TRACK INTO OUR REGION. THERE IS CERTAINLY SOME POTENTIAL FOR LOCALLY HEAVY RAINFALL AS PWAT VALUES CLIMB TO AROUND OR EVEN EXCEEDING TWO INCHES AND AS DEW POINTS REACH THE LOWER 70S. TEMPS WILL CONTINUE TO AVERAGE ABOVE TO POTENTIALLY MUCH ABOVE NORMAL THROUGH THE EXTENDED RANGE FCST PERIOD WITH MINS MAINLY IN THE UPPER 60S TO LOWER 70S AND HIGHS WELL INTO THE 80S WITH POTENTIAL TO REACH THE 90S DEPENDING ON EXTENT OF SUN. THERE IS SOME POTENTIAL FOR A CONVECTIVELY MORE ACTIVE WX PATTERN MID TO LATE WEEK DUE TO INCREASING MOISTURE AND POTENTIAL INSTABILITY. HOWEVER OVERALL WE FEEL THAT DRY AND VERY WARM TO HOT CONDITIONS WILL PREVAIL THE MAJORITY OF THE TIME DUE TO AN ABSENCE OF ANY STRONG SHORTWAVES OR LARGER SCALE SHIFT OF THE UPPER LEVEL PATTERN. LARGE AREAS OF SIGNIFICANT QPF IN THE GFS GUIDANCE ARE AN ARTIFACT OF WELL DOCUMENTED CONVECTIVE FEEDBACK ISSUES. && .AVIATION... (718 PM EDT SAT AUG 4 2007) RADAR AND TAMDAR DATA SUGGEST CLOUD BASES ABOVE 15000 FT AT 23Z. WARM ADVECTION LIFT WILL ALLOW CEILINGS TO SLOWLY LOWER OVER TIME. DUE TO THE EXTREMELY DRY AIR BELOW 15000 FT...SEEN ON TAMDAR SOUNDING.... THE LEAD EDGE OF THE RAIN WILL BE SLOW TO COME IN. I USED THE MEAN POSITION OF THE 850 TO 700 MB RH GREATER THAN 85 PCT TO FORECAST THE TIME RAIN WOULD START AT TAF SITES. THAT IS MOSTLY BETWEEN 09Z AND 12Z. FRONT WILL STRUGGLE TO MAKE IT NORTH AS MID AND UPPER LEVEL WINDS ARE FOR THE MOST PART PARALLEL TO THE FRONT. THUS I LOWERED CEILINGS TO MVFR AND FOR THE MOST PART ALLOWED THEM TO STAY THAT WAY THROUGH MOST OF THE DAY. MODELS SUGGEST THE BEST INSTABILITY WILL BE WELL SOUTH OF I-94 SO I DID NOT PLAY THUNDERSTORMS AS MUCH OF A FACTOR. EVEN SO...AN ISOLATED THUNDERSTORM OR TWO CANNOT BE RULED OUT PARTICULARLY AT THE SOUTHERN (AZO... BTL AND JXN) TAF SITES BY SUNDAY AFTERNOON. && .MARINE... (340 PM EDT SAT AUG 4 2007) NO HIGHLIGHTS ARE EXPECTED AS WINDS SHOULD STAY LIGHT CLOSE TO THE PASSING SURFACE LOW PRESSURE CENTER. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AFTER MIDNIGHT OVER LAKE MICHIGAN. WIND DIRECTIONS WILL BE QUITE VARIABLE THROUGH MONDAY WITH THIS LOW...ESPECIALLY NEAR CONVECTION. SEAS SHOULD REMAIN AROUND A FOOT OR LESS. && .HYDROLOGY... (340 PM EDT SAT AUG 4 2007) NO CONCERNS ARE EXPECTED FOR MAINSTREAM RIVERS GIVEN CURRENT LOW FLOWS. HAVE GONE ABOVE HPC QPF VALUES SOMEWHAT. RESULTS SHOULD BE LIMITED TO NUISANCE URBAN AND SMALL STREAM FLOODING IN SOME SPOTS. WILL OBVIOUSLY NEED TO MONITOR FOR TRAINING CELLS SUNDAY MORNING... ALTHOUGH AS NOTED ABOVE...SYSTEM IS EXPECTED TO BE PROGRESSIVE OVERALL. && .FIRE WEATHER...(340 PM EDT SAT AUG 4 2007) CLOUD COVER THIS AFTERNOON HAS PREVENTED RELATIVE HUMIDITIES FROM DROPPING AS FAR AS EXPECTED. THERE ARE NO CONCERNS SUNDAY DUE TO LIKELY PRECIPITATION. MONDAY SHOULD BE DRY...BUT HIGH RELATIVE HUMIDITIES SHOULD PRECLUDE ANY CONCERNS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SHORT TERM: NJJ/TJT LONG TERM: LAURENS AVIATION: WDM MARINE: TJT HYDROLOGY: TJT FIRE WEATHER: TJT
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
718 PM EDT SAT AUG 4 2007 LATEST UPDATE...AVIATION... .SYNOPSIS... (340 PM EDT SAT AUG 4 2007) A LOW PRESSURE SYSTEM OVER THE UPPER MIDWEST WILL MOVE EAST ACROSS SOUTHERN LOWER MICHIGAN BY SUNDAY EVENING. AHEAD OF THIS SYSTEM... SHOWERS AND THUNDERSTORMS WILL MOVE ACROSS LAKE MICHIGAN INTO SOUTHWEST LOWER MICHIGAN SUNDAY MORNING. DUE TO ABUNDANT MOISTURE LOCALLY HEAVY RAIN WILL BE POSSIBLE. && .SHORT TERM... (340 PM EDT SAT AUG 4 2007) TONIGHT THROUGH MONDAY - MAIN CONCERN IS QPF SUNDAY. GFS QPF SOLUTION IS CONSIDERABLY FARTHER S THAN NAM AND SREF SOLUTION...AND IS STRONGLY FAVORED BY HPC. GFS SOLUTION IS CLOSER TO THE SURFACE BOUNDARY THAT EXTENDED THROUGH NRN IL AND CENTRAL AT 17Z. UPSTREAM CONVECTION HAS BEEN ELEVATED AND WE EXPECT THIS TO BE THE CASE AGAIN OVERNIGHT. THUS...THE QPF MAXIMUM COULD BE FAR REMOVED FROM THE SURFACE BOUNDARY. CURRENT TRENDS APPEAR TO SUPPORT THE FARTHER NORTH NAM SOLUTION FOR HIGHER QPF. AFTER DISCUSSION WITH SURROUNDING OFFICES...HAVE DECIDED TO TAKE A BLEND OF GFS...NAM...AND OUR LOCAL WRF. OUR LOCAL WRF IS MOST AGGRESSIVE BY DROPPING AN AXIS OF 2+" PRECIP ALONG A HOLLAND-JACKSON LINE. THIS AXIS IS BETWEEN THE AXES OF THE NAM AND GFS SOLUTIONS. AT THIS POINT WE ARE NOT TOO CONCERNED ABOUT FLOODING...AS THE SYSTEM SHOULD BE FAIRLY PROGRESSIVE BASED ON MEAN WIND ORIENTATION. LATEST FORECAST SOUNDINGS ALSO SUGGEST A SHALLOWER WARM CLOUD DEPTH COMPARED TO EARLIER RUNS. LOCAL NUISANCE FLOODING CERTAINLY WILL BE POSSIBLE...ESPECIALLY SINCE SOIL IS BAKED AND QUITE IMPERMEABLE. WILL UPDATE THE HWO TO MENTION THIS. NEXT CONCERN IS STRONG/SEVERE CONVECTION SUNDAY AFTERNOON. THE SPC DAY2 OUTLOOK ISSUED AT 1730Z INCLUDED FAR SW LOWER MI IN A SLIGHT RISK. AT THIS POINT WE ARE NOT TOO CONCERNED...AS WE EXPECT MARGINAL INSTABILITY AND LIMITED INSOLATION DUE TO SIGNIFICANT CLOUDS. && .LONG TERM...(140 PM EDT SAT AUG 4 2007) THE SREF MEAN AS WELL AS GFS AND CANADIAN GUIDANCE SUGGESTS THAT ANOTHER MCS COULD POTENTIALLY AFFECT OUR CWFA TOWARDS DAYBREAK TUESDAY. HOWEVER THE GFS IS SUFFERING FROM SIGNIFICANT CONVECTIVE FEEDBACK ISSUES WHICH ARE EVIDENT IN THE STABLE VERSUS CONVECTIVE QPF AND UPPER LEVEL HEIGHT/VORT FIELDS AS WELL SPURIOUS EXCESSIVE QPF BULLSEYE. BASED ON CONF CALL COORDINATION WITH APX/DTX/IWX WE WILL ONLY MENTION A SLIGHT CHC OF CONVECTION LATE MONDAY NIGHT. THE BETTER CHANCE FOR RAIN AND CONVECTION WILL HOLD OFF UNTIL TUESDAY WITH GUIDANCE SUGGESTING A STRONGER LOW PRESSURE WAVE WILL TRACK INTO OUR REGION. THERE IS CERTAINLY SOME POTENTIAL FOR LOCALLY HEAVY RAINFALL AS PWAT VALUES CLIMB TO AROUND OR EVEN EXCEEDING TWO INCHES AND AS DEW POINTS REACH THE LOWER 70S. TEMPS WILL CONTINUE TO AVERAGE ABOVE TO POTENTIALLY MUCH ABOVE NORMAL THROUGH THE EXTENDED RANGE FCST PERIOD WITH MINS MAINLY IN THE UPPER 60S TO LOWER 70S AND HIGHS WELL INTO THE 80S WITH POTENTIAL TO REACH THE 90S DEPENDING ON EXTENT OF SUN. THERE IS SOME POTENTIAL FOR A CONVECTIVELY MORE ACTIVE WX PATTERN MID TO LATE WEEK DUE TO INCREASING MOISTURE AND POTENTIAL INSTABILITY. HOWEVER OVERALL WE FEEL THAT DRY AND VERY WARM TO HOT CONDITIONS WILL PREVAIL THE MAJORITY OF THE TIME DUE TO AN ABSENCE OF ANY STRONG SHORTWAVES OR LARGER SCALE SHIFT OF THE UPPER LEVEL PATTERN. LARGE AREAS OF SIGNIFICANT QPF IN THE GFS GUIDANCE ARE AN ARTIFACT OF WELL DOCUMENTED CONVECTIVE FEEDBACK ISSUES. && .AVIATION... (718 PM EDT SAT AUG 4 2007) RADAR AND TAMDAR DATA SUGGEST CLOUD BASES ABOVE 15000 FT AT 23Z. WARM ADVECTION LIFT WILL ALLOW CEILINGS TO SLOWLY LOWER OVER TIME. DUE TO THE EXTREMELY DRY AIR BELOW 15000 FT...SEEN ON TAMDAR SOUNDING.... THE LEAD EDGE OF THE RAIN WILL BE SLOW TO COME IN. I USED THE MEAN POSITION OF THE 850 TO 700 MB RH GREATER THAN 85 PCT TO FORECAST THE TIME RAIN WOULD START AT TAF SITES. THAT IS MOSTLY BETWEEN 09Z AND 12Z. FRONT WILL STRUGGLE TO MAKE IT NORTH AS MID AND UPPER LEVEL WINDS ARE FOR THE MOST PART PARALLEL TO THE FRONT. THUS I LOWERED CEILINGS TO MVFR AND FOR THE MOST PART ALLOWED THEM TO STAY THAT WAY THROUGH MOST OF THE DAY. MODELS SUGGEST THE BEST INSTABILITY WILL BE WELL SOUTH OF I-94 SO I DID NOT PLAY THUNDERSTORMS AS MUCH OF A FACTOR. EVEN SO...AN ISOLATED THUNDERSTORM OR TWO CANNOT BE RULED OUT PARTICULARLY AT THE SOUTHERN (AZO... BTL AND JXN) TAF SITES BY SUNDAY AFTERNOON. && .MARINE... (340 PM EDT SAT AUG 4 2007) NO HIGHLIGHTS ARE EXPECTED AS WINDS SHOULD STAY LIGHT CLOSE TO THE PASSING SURFACE LOW PRESSURE CENTER. SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE AFTER MIDNIGHT OVER LAKE MICHIGAN. WIND DIRECTIONS WILL BE QUITE VARIABLE THROUGH MONDAY WITH THIS LOW...ESPECIALLY NEAR CONVECTION. SEAS SHOULD REMAIN AROUND A FOOT OR LESS. && .HYDROLOGY... (340 PM EDT SAT AUG 4 2007) NO CONCERNS ARE EXPECTED FOR MAINSTEM RIVERS GIVEN CURRENT LOW FLOWS. HAVE GONE ABOVE HPC QPF VALUES SOMEWHAT. RESULTS SHOULD BE LIMITED TO NUISANCE URBAN AND SMALL STREAM FLOODING IN SOME SPOTS. WILL OBVIOUSLY NEED TO MONITOR FOR TRAINING CELLS SUNDAY MORNING... ALTHOUGH AS NOTED ABOVE...SYSTEM IS EXPECTED TO BE PROGRESSIVE OVERALL. && .FIRE WEATHER...(340 PM EDT SAT AUG 4 2007) CLOUD COVER THIS AFTERNOON HAS PREVENTED RELATIVE HUMIDITIES FROM DROPPING AS FAR AS EXPECTED. THERE ARE NO CONCERNS SUNDAY DUE TO LIKELY PRECIPITATION. MONDAY SHOULD BE DRY...BUT HIGH RELATIVE HUMIDITIES SHOULD PRECLUDE ANY CONCERNS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SHORT TERM: TJT LONG TERM: LAURENS AVIATION: WDM MARINE: TJT HYDROLOGY: TJT FIRE WEATHER: TJT
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
125 AM EDT FRI AUG 3 2007 UPDATED FOR 06Z TAF ISSUANCE .UPDATE (ISSUED AT 743 PM EDT THU AUG 2)... ISSUED A RED FLAG WARNING EARLIER TO INCLUDE MUCH OF THE WEST HALF OF UPPER MICHIGAN AFTER COORDINATION WITH MICHIGAN DNR AND USFS. RHS MADE A VERY QUICK FALL LATE THIS AFTERNOON AS LOW PRECIPITABLE WATER AIRMASS ADVECTING IN BEHIND THE FRONTAL PASSAGE LAST NIGHT COMBINED WITH DEEP MIXING. 18Z TAMDAR SOUNDING FROM SAW LOOKED EXTREMELY DRY WHILE MIXED UP TO 800MB. COORDINATION WITH USERS ALSO REVEALED QUITE A FEW SMALL FIRES DEVELOPED THIS AFTERNOON... INCLUDING ONE THAT CAN BE SEEN ON VISIBLE SATELLITE AND 3.9 UM IMAGERY ABOUT 4 MILES SE OF PINE STUMP JUNCTION IN LUCE COUNTY. WITH THE SUN GOING DOWN...RELATIVE HUMIDITIES ARE STARTING TO CLIMB BACK UP AND WINDS ARE DIMINISHING...THUS THE EXPIRE TIME OF 8 PM EDT LOOKS GOOD. IN ADDITION...HAVE LOWERED DEWPOINTS TOMORROW GIVEN THE FACT THAT THE AIRMASS UPSTREAM IS AS JUST AS DRY AS THAT OVER US NOW. GOING HIGH TEMPERATURES FOR FRIDAY LOOKED OKAY...THUS THE AREA CURRENTLY EXPERIENCING LOW RELATIVE HUMIDITIES MAY SEE SIMILAR READINGS TOMORROW. HOWEVER...TEMPERATURES ARE NOT AS HIGH AS THEY ARE TODAY...THUS THE RH VALUE SHOULD BE A BIT HIGHER...AROUND THE RED FLAG CRITERIA OF 25 PERCENT. AS FOR RED FLAG POTENTIAL TOMORROW... THE BIG QUESTION IS WHETHER THE WINDS WILL REACH CRITERIA. RIGHT NOW THEY LOOK TO BE AROUND 10 KNOTS OVER THE AREA THAT SEES THE LOWEST RELATIVE HUMIDITIES...WHICH WOULD BE JUST UNDER CRITERIA. NAM SOUNDINGS WOULD NOT SUGGEST MUCH GUSTING...THOUGH THE 13 KM RUC SHOWS 20 KNOT GUSTS (SIMILAR TO TODAY) OVER THE LOW RELATIVE HUMIDITY AREA. AFTER COORDINATION WITH MICHIGAN DNR AND USFS...HAVE DECIDED TO GO WITH A FIRE WEATHER WATCH. IF WINDS LOOK LIKE THE 13 KM RUC AND THE RELATIVE HUMIDITIES ARE CERTAIN TO FALL TO THE 25 PERCENT LEVEL DURING THE MIDNIGHT SHIFT...THE WATCH CAN BE UPGRADED TO A RED FLAG WARNING. && .SHORT TERM (TONIGHT AND FRI)... THE UPPER AIR PATTERN CONSISTS OF A 500 MB RIDGE ACROSS THE WESTERN U.S. WITH A TROUGH ACROSS THE GREAT BASIN...A TROUGH ACROSS CENTRAL CANADA DOWN INTO THE UPPER GREAT LAKES AND RIDGING ACROSS THE ERN U.S. FAIRLY STRONG 500 MB CLOSED LOW ALONG THE HUDSON BAY SHORELINE OF MANITOBA/ONTARIO WITH STRONG CYCLONIC SPIN NOTED ON WATER VAPOR AND WRAPAROUND MOISTURE HEADING SOUTHEAST. TROUGH REMAINS IN PLACE WITH A SHORTWAVE MOVING THROUGH IT THIS AFTERNOON AND EARLY EVENING. PROBLEM IS VERY LITTLE MOISTURE IS AVAILABLE AS IT LOOKS LIKE WITH EXTRAPOLATION THAT THE WRAPAROUND MOISTURE WILL STAY TO THE NORTH. DRY AIR CONTINUES TO WORK ITS WAY INTO THE AREA AS DEW POINTS HAVE DROPPED INTO THE 40S AND 50S ACROSS THE WESTERN HALF OF THE CWA LATE THIS MORNING. DRY AIR HAS MADE IT FAR ENOUGH EAST THAT IS HAS SUPPRESSED CONVECTION ON THE LAKE MICHIGAN LAKE BREEZE FOR THE MOST PART AS CONVECTION TRIED TO GO TO THE EAST AND SOUTH OF THE AREA THIS AFTERNOON. OVERALL...QUIET WEATHER WILL CONTINUE. DID NOT MAKE TOO MANY CHANGES TO THE GOING FORECAST TEMPERATURE WISE AS WHAT WE HAD IN THERE LOOKED GOOD. WENT CLOSE TO ADJMAV FOR LOWS AND HIGHS WITH A FEW MINOR TWEAKS HERE AND THERE. PLENTY OF SUNSHINE SHOULD ALLOW MIXING 850 MB TEMPERATURES DOWN TO THE SFC FOR HIGHS WHICH GIVES ME CLOSE TO ADJMAV CONDITIONS. .LONG TERM (FRI NIGHT THROUGH NEXT WED)... THE LOW OVER SOUTHEAST HUDSON BAY WILL CONTINUE TO TREK EAST FRIDAY NIGHT AND SATURDAY AS THE RIDGE OVER SASKATCHEWAN SHIFT INTO MANITOBA. MEANWHILE...A SHORTWAVE WILL SLIDE THROUGH WISCONSIN ON SATURDAY. THE AIR MASS WILL REMAIN DRY OVER THE FORECAST AREA. A SHORTWAVE WILL MOVE INTO THE WESTERN U.P. ON SATURDAY NIGHT AND SUNDAY. GFS TRIES TO KEEP THIS SOUTH OF THE FORECAST AREA...WHEREAS NAM/ECMWF/GEM MOVE THE SHORTWAVE INTO THE U.P. WILL FAVOR THE MAJOR SOLUTION AND KEEP A CHANCE OF SHOWERS AND THUNDERSTORMS. A SURFACE LOW WILL MOVE ACROSS JAMES BAY INTO WEST CENTRAL QUEBEC SUNDAY NIGHT DRAGGING A COLD FRONT OUT OF THE NORTHERN PLAINS INTO THE NORTHERN MISSISSIPPI RIVER VALLEY. VERY WEAK SHORTWAVES WILL ACCOMPANY THIS FRONTAL SYSTEM. ISENTROPIC ASCENT AHEAD OF THE FRONT ALONG WITH MID LEVEL INSTABILITY WILL PRODUCE SOME SHOWERS AND THUNDERSTORMS. LIMITING FACTOR WILL THE AMOUNT OF AVAILABLE MOISTURE. THIS WILL PERSIST THROUGH MONDAY. IN THE AFTERNOON TEMPERATURES WILL REACH TO AROUND 80 WHICH WILL SUPPORT SOME LAKE BREEZES CONVERGENCE WHICH COULD AIDE IN THE DEVELOPMENT OF MORE SHOWERS. THUS WILL KEEP A CHANCE GOING THROUGH THE PERIOD FOR NOW. A NEW ZONAL FLOW WILL SET UP ACROSS THE NORTHERN CONUS. A SHORTWAVE WILL MOVE THROUGH THE FORECAST AREA MONDAY NIGHT FOLLOWED BY ANOTHER ON TUESDAY. A SURFACE LOW MOVING UP THE FRONT WILL MOVE ACROSS NORTHERN LAKE MICHIGAN. MOIST AIR WILL SPREAD INTO THE AREA WRAPPING AROUND THE LOW. THE COLD FRONT WILL CONTINUE TO SHIFT SOUTHEAST INTO THE LOWER GREAT LAKES TUESDAY NIGHT AND WEDNESDAY. FOLLOWED BY A WEAK RIDGE WHICH WILL MOVE INTO THE U P ON WEDNESDAY. A WEAK SHORTWAVE WILL RACE ACROSS THE FORECAST AREA ON WEDNESDAY. LOW LEVEL MOISTURE WILL BE VERY LIMITED. LAKE BREEZES SHOULD SET UP AND COULD POSSIBLY TRIGGER A SHOWERS WITH THUNDER OR TWO...SO WILL KEEP A SLIGHT CHANCE GOING FOR NOW. MORE DRY AIR WILL MOVE INTO THE FORECAST AREA UNDER THE INFLUENCE OF A HIGH LATE WEDNESDAY...SO WILL DROP EVEN A MENTION OF EVEN A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS. CONDITIONS WILL REMAIN DRY THROUGH THE REST OF THE WEEK NEXT WEEK. && .AVIATION (FOR THE 06Z TAF ISSUANCE)... VFR CONDITIONS AND CLEAR SKIES ARE EXPECTED TO CONTINUE THROUGH THE NEXT 24 HOURS WITH DRY HIGH PRESSURE BUILDING IN. WINDS WILL PICK BACK UP AGAIN AT THE TAF SITES WITH DAYTIME HEATING ON FRI...BUT DEFINITELY NOT AS STRONG AS YESTERDAY. IN ADDITION...A LAKE BREEZE FROM LAKE SUPERIOR MAY ENTER SAW LATE FRIDAY AFTERNOON. EXPECT WINDS TO DIMINISH FRI EVENING AS THE HIGH PRESSURE AREA MOVES OVERHEAD. && .MARINE (FOR 4 PM LAKE SUPERIOR FORECAST ISSUANCE)... 10 TO 20 KT WINDS WILL CONTINUE ACROSS THE LAKE TONIGHT AS A SECONDARY COLD FRONT TIGHTENS GRADIENT OVR ENTIRE LAKE THIS EVENING INTO MUCH OF FRIDAY. WINDS DIMINISH SUBSTANTIALLY BY FRI EVENING AS HIGH PRES RIDGE MOVES IN. DESPITE ANOTHER LOW PRES SYSTEM/WARM FRONT AFFECTING THE UPPER GREAT LAKES BY EARLY NEXT WEEK...EXPECT WINDS TO REMAIN BLO 20 KT AND NO GALES FORESEEN. $$ .MQT WATCHES/WARNINGS/ADVISORIES... FIRE WEATHER WATCH FOR THIS AFTERNOON AND EVENING MIZ001>005-009>013-084. && $$ UPDATE/AVIATION...AJ SHORT TERM/MARINE...GM LONG TERM...DLG
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
300 AM MDT FRI AUG 3 2007 .DISCUSSION... 400-250MB AIRCRAFT WIND PLOT EARLY THIS MORNING SHOWS THE UPPER LEVEL HIGH CENTER OVER KGUP...A 40-60 KNOT SOUTHWESTERLY JET OVER THE GREAT BASIN...AND A 20-30 KNOT NORTHEASTERLY JET OVER NE NM. WATER VAPOR LOOP SHOWS THE MAIN MOISTURE PLUME SHIFTING OVER WESTERN NM WHERE THE GOES SOUNDER HAS PICKED UP A FEW PWAT PIXELS AROUND 2.0 INCHES. LOWEST PWAT VALUES ARE OVER NE NM WHERE DRYING HAS BEEN DEVELOPING SINCE THURS EVE. 08Z SFC ANALYSIS SHOWS A BROAD AREA OF SFC LOW PRES OVER WESTERN NM BENEATH THIS MOISTURE PLUME WITH THE 08Z RUC ANALYSIS SHOWING THE BEST LOW LEVEL MOISTURE CONVERGENCE OVER THIS AREA. THINK THE BEST CHANCE FOR HEAVY RAINFALL TODAY WILL BE ALONG AND WEST OF THE CONTINENTAL DIVIDE PER LATEST OBSERVED SATELLITE TRENDS...RUC ANALYSIS...AND THE GENERAL AGREEMENT AMONGST THE 00Z GFS/NOGAPS/NGM. RAISED POPS IN THIS AREA AND CONTINUED MENTION OF HEAVY RAINFALL. A FEW SHOWERS AND STORMS WILL ALSO DEVELOP OVER THE CENTRAL MTNS THIS AFTERNOON HOWEVER COVERAGE SHOULD BE LIMITED COMPARED TO THURS SINCE THE BEST UPPER LEVEL DYNAMICS ARE SHIFTING INTO THE WESTERN HALF OF THE STATE. STILL HAVE TO CONTEND WITH HIGH CHANCE POPS OVER THE SE AND SACRAMENTO MTNS AS A WEAK UPPER DISTURBANCE OVER W TX SHIFTS SLOWLY WESTWARD TOWARD KELP. 06Z MREF/03Z SREF SOLUTIONS IN GOOD AGREEMENT THAT A 576DM H5 TROUGH BUILDING OVER THE NW CONUS OVER THE WEEKEND WILL PUSH THE MOISTURE PLUME EASTWARD INTO THE CENTRAL PORTIONS OF THE STATE AS SW FLOW DEVELOPS OVER THE GREAT BASIN. RAISED POPS OVER THE CENTRAL MTNS AND VALLEYS SAT AND SUN. MODELS THEN DISAGREE ON HOW FAR EAST THE MAIN MOISTURE PLUME SETS UP INTO EARLY NEXT WEEK. LEFT EXTENDED SLIGHT CHANCE/CHANCE POPS UNCHANGED TO AWAIT TRENDS FROM 12Z MODEL RUNS. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 89 64 88 64 / 50 50 40 40 GALLUP.......................... 82 58 83 58 / 60 50 50 40 GRANTS.......................... 84 58 81 57 / 40 50 50 40 GLENWOOD........................ 84 63 84 62 / 50 60 50 40 CHAMA........................... 81 53 77 50 / 60 60 50 40 LOS ALAMOS...................... 79 57 83 57 / 40 40 50 40 RED RIVER....................... 77 47 72 46 / 50 40 50 30 TAOS............................ 82 54 82 54 / 30 30 50 30 SANTA FE........................ 81 57 81 59 / 40 30 50 30 SANTA FE AIRPORT................ 83 59 83 60 / 30 30 40 30 ESPANOLA........................ 85 59 88 60 / 30 20 30 20 ALBUQUERQUE HEIGHTS............. 88 67 87 67 / 30 30 40 30 ALBUQUERQUE VALLEY.............. 91 64 89 65 / 30 30 40 30 ALBUQUERQUE FOOTHILLS........... 86 63 84 63 / 40 30 40 30 ALBUQUERQUE WEST MESA........... 90 65 88 65 / 30 30 40 30 SOCORRO......................... 89 64 88 63 / 30 30 40 30 SANDIA PARK/CEDAR CREST......... 80 55 79 57 / 40 30 50 30 MORIARTY/ESTANCIA............... 82 57 85 58 / 30 30 40 20 CARRIZOZO....................... 84 60 83 61 / 30 30 30 30 RUIDOSO......................... 74 52 76 54 / 50 40 50 30 RATON........................... 81 57 81 58 / 30 20 30 30 LAS VEGAS....................... 78 56 78 56 / 20 20 30 30 ROY............................. 80 61 86 63 / 10 20 20 20 CLAYTON......................... 85 63 89 64 / 10 10 20 10 SANTA ROSA...................... 85 61 90 64 / 20 20 20 20 TUCUMCARI....................... 87 66 92 68 / 20 10 10 10 FORT SUMNER..................... 84 65 91 66 / 20 20 10 10 CLOVIS.......................... 81 64 88 65 / 30 20 10 10 PORTALES........................ 83 65 90 66 / 30 30 10 10 ROSWELL......................... 84 66 90 68 / 50 30 20 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 42
AREA FORECAST DISCUSSION
NWS SEATTLE WA
915 AM PDT FRI AUG 3 2007 .SYNOPSIS...A DEEP MARINE LAYER AND UPPER LEVEL TROUGH IS OVER WESTERN WASHINGTON. A PUGET SOUND CONVERGENCE ZONE WILL CONTINUE TO TOUCH OFF DRIZZLE AND SHOWERS THIS MORNING...WITH MOST OF THE PRECIPITATION BETWEEN SEATTLE AND EVERETT. A WEAK UPPER LEVEL TROUGH WILL REMAIN OVER THE PACIFIC NORTHWEST INTO EARLY NEXT WEEK. && .SHORT TERM...WEAK UPPER TROF OVER THE REGION. NOT A LOT ON THE RADAR BUT THERE IS PRECIP IN THE PSCZ AREA. KICKED THE POPS UP A NOTCH AND REWORDED THE FORECAST FOR THE METRO AREA...PRECIP IS MOSTLY SEATTLE TO EVERETT. THE CLOUDS WILL BUBBLE UP FOR PARTLY SUNNY AREAS OR AT LEAST SUNBREAKS IN MANY AREAS...BUT NOT PROBABLY THE METRO AREA WITH THE PSCZ. MM .LONG TERM...WITH LONG WAVE RIDGES PLANTED OVER THE CENTRAL PART OF THE US AND OUT OVER THE PACIFIC NEAR 150W...THE PATTERN WILL REMAIN RATHER STAGNANT OVER THE REGION. BY DEFAULT...THE PLACEMENT OF THOSE RIDGES RESULTS IN A WEAK TROUGH ALONG OR NEAR THE WEST COAST THROUGH THE LONG (AND POSSIBLY VERY LONG TERM) PERIOD. ALTHOUGH NOT A WET PATTERN...THE RESULT WILL BE VARYING AMOUNTS OF ONSHORE FLOW...WITH THE POTENTIAL OF LATE NIGHT AND MORNING MARINE CLOUDINESS...AND TEMPERATURES WITHIN A FEW DEGREES OF NORMAL FOR THIS TIME OF YEAR. FOR HIGH TEMPERATURES...THIS MEANS AROUND 70 ON THE COAST AND 70S TO NEAR 80 OVER THE INTERIOR. CERNIGLIA && .AVIATION...UPPER LEVEL LOW ACROSS SOUTHERN BC WITH STRONG ONSHORE GRADIENTS BROUGHT LOW LEVEL STRATUS/MARINE LAYER ALL THE WAY TO THE CASCADES THIS MORNING. POCKETS OF LIGHT RAIN SHOWERS AND DRIZZLE ALSO NOTED ACROSS THE COAST AND PUGET SOUND AREA FROM KSEA TO KPAE. MARINE LAYER IS PRETTY THICK WITH 13Z ACARS SOUNDINGS FROM KBFI INDICATING CLOUD TOPS AROUND 5500FT AGL. THE VISIBLE SATELLITE DOES SHOW A FEW BREAKS IN THE SW INTERIOR AND N PUGET SOUND...BUT OVERALL NOT EXPECTING WIDESPREAD IMPROVEMENTS TO THE CONDITIONS TODAY. KSEA...LIGHT RAIN/DRIZZLE DIMINISHING BY 18-19Z BUT LOW CEILINGS PERSISTING THROUGH THE MORNING AND INTO THE AFTERNOON WITH CIGS OVC010. MAY SEE SOME IMPROVEMENT LATER TODAY WITH CEILING LIFTING TO OVC030 AFT 23Z. WINDS TODAY S TO SW 8-15KT WITH A SWITCH TO THE W THIS EVENING. && .SEW WATCHES/WARNINGS/ADVISORIES... .SMALL CRAFT ADVISORY CENTRAL AND EAST STRAIT. $$ WEATHER.GOV/SEATTLE
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
305 AM MDT SUN AUG 5 2007 .DISCUSSION... WATER VAPOR LOOP EARLY THIS MORNING SHOWS MOISTURE PLUME IN A SQUEEZE PLAY BETWEEN AN ELONGATED AREA OF HIGH PRESSURE OVER TEXAS AND AN UPPER LEVEL LOW MOVING ONSHORE THE CA COASTLINE NEAR KSFO. 400-250MB AIRCRAFT WIND PLOT SHOWS THE ELONGATED UPPER HIGH CENTER OVER SW KS...AN 80-100 KNOT SW JET OVER THE INTER MOUNTAIN WEST...AND A 20-40 KNOT EASTERLY JET OVER W TX PUSHING INTO E NM. 08Z SFC ANALYSIS SHOWS A 1005MB LOW PRES CENTER OVER SE CO WITH A TROUGH EXTENDING SW INTO E NM. SOME MODEL DIFFERENCES THIS MORNING BETWEEN THE 00Z NAM/GFS WITH RESPECT TO THE LOCATION OF THE CURRENT MOISTURE PLUME AND DISTURBANCES EMBEDDED WITHIN THE FLOW. NOTICED THE MODELS TENDING TO PLACE THE PLUME TOO FAR EAST OVER THE PAST FEW DAYS AND THE 00Z GFS IS CERTAINLY SHOWING THIS MORE THAN THE NAM. NUDGED POPS FARTHER NORTH AND WEST AGAIN TODAY MORE IN LINE WITH THE 00Z MM5 SOLUTION AND USED A BLEND OF THE GFS/NAM. LOWERED POPS AND RAISED TEMPS A FEW DEGREES IN THE E PLAINS AS 500MB TEMPS NEAR 0C AND MID LEVEL DRYING DEVELOPS IN ASSCN WITH ELONGATED RIDGE PUSHING WEST. WENT BELOW MAVMOS POPS OVER THE GILA REGION AS WELL WITH THE 20-40 KNOT JET PUSHING THE MOISTURE PLUME WEST INTO E AZ. BEYOND SUNDAY...THE 06Z MREF/03Z SREF SOLNS ARE SHOWING A SLIGHTLY DEEPER 576DM H5 TROUGH OVER THE NW CONUS THAN PREVIOUS RUNS INDICATING STRONGER SW FLOW MAY DEVELOP OVER THE GREAT BASIN THROUGH THE MIDDLE OF THE WEEK. COMPLICATING FACTOR IN THIS SCENARIO WILL BE HOW MUCH DRYING DEVELOPS OVER THE SW CONUS AND THE PLACEMENT OF THE MOISTURE PLUME AXIS AS IT SHEARS OUT OVER NM. IN ADDITION...A RATHER IMPRESSIVE LOOKING EASTERLY WAVE PUSHING WEST OVER THE YUCATAN THIS MORNING MAY THROW ANOTHER WRENCH IN THE EXTENDED. SHIFTED AXIS OF BEST POPS SLIGHTLY EAST INTO THE CENTRAL PORTIONS OF THE STATE IN LINE WITH LATEST TRENDS OF STRONGER SW FLOW OVER THE SW CONUS. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 91 66 89 64 / 40 40 40 30 GALLUP.......................... 83 60 82 58 / 30 50 40 40 GRANTS.......................... 85 57 84 57 / 30 40 40 40 GLENWOOD........................ 86 63 86 63 / 40 30 30 20 CHAMA........................... 78 54 76 51 / 60 60 50 40 LOS ALAMOS...................... 85 57 85 56 / 30 40 30 30 RED RIVER....................... 74 49 72 50 / 50 50 40 30 TAOS............................ 86 56 86 54 / 30 30 30 30 SANTA FE........................ 86 59 85 58 / 30 30 30 30 SANTA FE AIRPORT................ 88 61 87 60 / 30 30 30 30 ESPANOLA........................ 91 62 90 61 / 20 30 20 20 ALBUQUERQUE HEIGHTS............. 91 68 90 67 / 20 30 30 30 ALBUQUERQUE VALLEY.............. 93 66 92 65 / 20 30 30 30 ALBUQUERQUE FOOTHILLS........... 88 66 87 64 / 30 30 30 30 ALBUQUERQUE WEST MESA........... 92 67 91 66 / 20 30 30 30 SOCORRO......................... 92 67 93 67 / 20 20 20 20 SANDIA PARK/CEDAR CREST......... 87 61 86 60 / 30 30 30 30 MORIARTY/ESTANCIA............... 89 55 89 56 / 20 30 20 30 CARRIZOZO....................... 88 66 90 65 / 20 10 20 20 RUIDOSO......................... 80 59 80 60 / 20 20 30 30 RATON........................... 87 58 88 56 / 30 30 30 20 LAS VEGAS....................... 86 58 85 55 / 20 30 20 20 ROY............................. 91 67 90 64 / 10 10 20 10 CLAYTON......................... 94 67 95 67 / 20 20 20 10 SANTA ROSA...................... 95 68 96 69 / 10 10 10 20 TUCUMCARI....................... 98 69 98 70 / 5 5 10 10 FORT SUMNER..................... 96 69 97 69 / 5 5 10 10 CLOVIS.......................... 92 66 94 67 / 5 0 10 5 PORTALES........................ 93 67 95 67 / 5 0 10 5 ROSWELL......................... 95 69 97 70 / 5 5 10 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 42
AREA FORECAST DISCUSSION
NWS ABERDEEN SD
310 AM CDT SUN AUG 5 2007 .SHORT TERM...TODAY THROUGH MONDAY NIGHT STRATUS DECK REMAINS IN PLACE ACROSS THE ENTIRE EASTERN CWA AND HAS EXPANDED WESTWARD UP TO THE MISSOURI RIVER. BIGGEST FORECAST CHALLENGE FOR TODAY WILL BE TIMING THE EROSION OF CLOUDS AND WHAT EFFECT THIS WILL HAVE ON HIGH TEMPS. TAMDAR AND MODEL SOUNDINGS REVEALING A SHALLOWER CLOUD DECK COMPARED TO YESTERDAY WHICH SHOULD ALLOW FOR A GRADUAL EROSION OF THE CLOUDS BY AFTERNOON ACROSS THE EAST. 925 RH FIELDS SHOW PLENTY OF MOISTURE REMAINING IN PLACE FROM THE JAMES VALLEY AND POINTS EAST THROUGH LATE MORNING. WINDS AT THIS LEVEL THOUGH ARE RATHER LIGHT AND THERE IS NO APPRECIABLE ADVECTION OF DRIER AIR INTO THIS CLOUD LAYER. EROSION WILL MORE THAN LIKELY DEPEND ON SUNSHINE GRADUALLY BREAKING THINGS UP. HIGH TEMPS TODAY RATHER DIFFICULT ACROSS THE EAST SINCE IT ALL DEPENDS ON HOW MUCH CLOUD COVER IS EXPERIENCED IN THIS AREA. FOR NOW...HAVE TEMPS RISING TO THE UPPER 70S TO AROUND 80 OVER THE FAR EAST...WARMING SLIGHTLY INTO THE LOW TO MID 80S OVER THE JAMES VALLEY. CLOUD TRENDS AND TEMPS WILL HAVE TO BE MONITORED CLOSELY THIS MORNING. MORNING FOG WILL BE LEFT IN THE GRIDS AS AREAS EAST OF THE JAMES RIVER ARE AROUND 2SM OR LESS...WHILE MBG/PIR ALSO BEGINNING TO SEE 4-5SM BR JUST ON THE EDGE OF THE STRATUS DECK. TURNING TO PRECIPITATION...ENERGY ALOFT WILL MOVE ACROSS THE AREA EARLY THIS MORNING AND MODELS TRYING TO GENERATE PRECIP ACROSS SOUTHERN ND. RUC IS EVEN PICKING UP ON SOMETHING MOVING ACROSS THIS AREA. RUC UPPER LEVEL ANALYSIS DOES SHOW A FEW EMBEDDED VORT MAXIMA JUST TO OUR WEST ALONG WITH MODEST LIFT. HAVE INSERTED SLIGHT CHANCE POPS ACROSS THE EXTREME NORTHERN CWA THROUGH THE MORNING HOURS TO ACCOUNT FOR THIS. LEFT SLIGHT CHANCE POPS IN FOR LATER THIS AFTERNOON AS SURFACE TROUGH PUSHES INTO WESTERN SD. BETTER CHANCE FOR STORMS MIGHT REMAIN IN WESTERN SD WHERE BETTER UPSLOPE COMPONENT CAN BE REALIZED. MONDAY STILL LOOKS INTERESTING AS MODELS ARE IN DECENT AGREEMENT IN BRINGING AN AREA OF SHOWERS AND STORMS EASTWARD ACROSS NORTHERN SD/SOUTHERN ND. UPPED POPS SLIGHTLY DURING THE DAY MONDAY. WEST TO EAST FRONTAL BOUNDARY SPLITS STATE IN HALF AND PLACEMENT OF THIS BOUNDARY WILL BE IMPORTANT IN DETERMINING WHERE BEST WAA/LIFT AND ASSOCIATED PRECIP WILL BE. .LONG TERM...TUESDAY THROUGH SATURDAY. BIGGEST CHALLENGE STILL FACING THE LONG TERM IS PRECIPITATION POSSIBILITIES THROUGH THE TIME PERIOD. LATEST ITERATION OF THE MODELS STILL SUGGESTS A MORE ACTIVE WEATHER PATTERN SHAPING UP FOR THE NORTHERN PLAINS...WITH UPPER RIDGE GETTING SURPRESSED SOMEWHAT WITH CWA GETTING INTO A MORE WESTERLY/SW FLOW PATTERN. MODELS ARE STILL HINTING AT SEVERAL FROPAS THROUGH THE TIME PERIOD...BUT DIFFERENCES ARE SETTING UP BETWEEN THE EC/CANADIAN AND GFS. ALSO TIMING DIFFERENCES BETWEEN THE WAVES PUSHING THROUGH ARE LEADING TO A LESS CONFIDENT FORECAST. GFS PCPN FORECAST SEEMS TO BE RULED BY CONVECTIVE FEEDBACK ISSUES...SO LITTLE CONFIDENCE IN THAT SOLN. OPTED TO STAY WITH PERSISTENCE FORECAST...MAKING ONLY COSMETIC CHANGES TO INHERITED WEATHER GRIDS. AS LONG TERM EVOLVES INTO SHORT TERM...WILL BE ABLE TO BETTER FINE TUNE DETAILS. TIMING OF EACH WAVE WILL IMPACT MAX T GRIDS...BASED ON ASSOCIATED CLOUD COVER AND PRECIPITATION. ALSO OPTED TO REMAIN FAIRLY CONSISTENT HERE...TWEAKING INHERITED MAX/MIN T GRIDS. && .AVIATION... BROAD AREA OF STRATUS EXTENDS FROM MO RIVER EAST INTO MINNESOTA...WITH IFR/MVFR CIGS IN PLACE. EXPECT VSBYS TO FALL TO 3-5SM BR BY 10Z FOR MUCH OF THE AREA...WITH ISOLD-SCT VSBYS 0-1SM FG. VSBYS SHOULD IMPROVE TO P6SM BETWEEN 14Z AND 16Z. STRATUS DECK SHOULD BEGIN TO LIFT AROUND 15Z ON WESTERN EDGE...BECOMING SCT- BKN020-030 BY 18Z FOR REMAINDER OF AREA. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ SHORT TERM...TMT LONG TERM...HINTZ AVIATION...HINTZ
AREA FORECAST DISCUSSION...UPDATED
NWS BALTIMORE MD/WASHINGTON DC
957 AM EDT SUN AUG 5 2007 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN NEARLY STATIONARY OVER THE AREA THROUGH LATE MONDAY. HIGH PRESSURE WILL BE THE RULE FOR TUESDAY AND WEDNESDAY. A BACKDOOR FRONT WILL BECOME NEARLY STATIONARY OVER THE NORTHERN PORTION OF THE CWFA BY THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WATER VAPOR LOOP SHOWS A PAIR OF MCVS EMBEDDED IN NORTHWEST FLOW...THE FIRST OVER THE OHIO VALLEY...FOLLOWED BY A MCV OVER CHICAGOLAND. ACARS 400-250MB WIND OBSERVATIONS REVEAL A 90-130KT JET WHICH RIDGES ACROSS THE ROCKIES...AND TROUGHS ACROSS THE CANADIAN MARITIMES. 11Z SURFACE ANALYSIS PLACED A DISSIPATING FRONT FROM THE MIDWEST SOUTHEAST THROUGH THE CAROLINAS. THE MAIN BAROCLINIC ZONE EXTENDS FROM THE MIDWEST SOUTHEAST THROUGH CHICAGO AND NEAR WASHINGTON DC. A 1020MB ANTICYCLONE WAS BUILDING ACROSS NEW ENGLAND. CLOUDINESS ASSOCIATED WITH CONVECTIVE COMPLEX WILL CONTINUE TO BLANKET THE REGION THIS AFTERNOON. MEANWHILE...SURFACE BOUNDARY EXPECTED TO BECOME QUASI STATIONARY AS IT BISECTS THE FORECAST AREA FROM NW TO SE. INCREASE IN ISENTROPIC LIFT AHEAD OF MCV SHOULD LEAD TO SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT AHEAD OF THE CONVECTIVE COMPLEX. MODERATE SURFACE BASED INSTABILITY EXISTS SOUTH OF THE BOUNDARY WHERE THE 12Z KIAD RAOB ADJUSTED FOR 87/67 YIELDED 1500 J/KG MIXED LAYER CAPE. GIVEN STRAIGHTENING NW FLOW ALOFT AND INCREASE IN DYNAMICAL LIFT THIS AFTERNOON...SOME OF THE STORMS MAY BECOME SEVERE WITH DAMAGING WIND GUSTS BEING THE PRIMARY THREAT. IN ADDITION...PRECIPITABLE WATER VALUES ARE FORECAST TO RISE TO NEAR 2 INCHES...SUPPORTED BY GPS SENSORS IN THE OHIO VALLEY. THIS COULD LEAD TO LOCALLY HEAVY RAINFALL. TWEAKED HIGHS A LITTLE TO COMPENSATE FOR INCREASING CLOUDS AND POP COVERAGE. WINDS WERE BASED ON THE LWX 4KM WRF-ARW. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/... INCREASED CONVECTIVE COVERAGE TO NUMEROUS FOR MOST OF THE CWA THIS EVENING...SUPPORTED BY 00Z NAM AND GFS GUIDANCE AND 21Z SHORT RANGE ENSEMBLE FORECASTS. THIS IS ASSOCIATED WITH ENERGY FROM THE MESOSCALE CONVECTIVE SYSTEM WHICH IS FORECAST TO MOVE NEARLY WEST TO EAST AND AFFECT MUCH OF THE CWA WITH SOME NEEDED RAINFALL...ALTHOUGH SOME OF IT COULD BE HEAVY. POPULATED MIN T USING THE WARMER ADJUSTED MET MOS...GIVEN ITS LOW TEMPERATURE SUPERIORITY OF LATE...AND GIVEN THE ANTICIPATED CONVECTION/CLOUDS. FRONT WILL HAVE MOVED NORTH TOWARD THE MASON DIXON LINE LATE IN THE NIGHT. && .LONG TERM /MONDAY THROUGH SATURDAY/... HOT AND HUMID CONDITIONS WILL BE THE RULE FOR MOST OF THE EXTENDED FORECAST PERIOD. AT THE BEGINNING OF THE PERIOD...A MID LEVEL HIGH IS CENTERED OVER THE GULF STATES. A LONGWAVE TROUGH IS SITUATED JUST OFF THE EASTERN SEABOARD. NW FLOW ALOFT ON MONDAY WILL GIVE WAY TO ZONAL FLOW ON TUESDAY AS THE RIDGE BUILDS EAST OVER THE MID ATLANTIC. THE MAIN MID LEVEL FORCING THROUGH MID WEEK WILL COME IN THE FORM OF SHORTWAVE IMPULSES ROUNDING THE NORTHERN PERIPHERY OF THE RIDGE IN PLACE. THE 500MB HIGH CENTER BEGINS TO SHIFT BACK WESTWARD BY THE END OF THE WEEK AS A TROUGH FORMS ALONG THE EASTERN SEABOARD ONCE AGAIN. SOMEWHAT COMPLICATED SURFACE PATTERN ON TAP FOR THE UPCOMING WORK WEEK. A TROUGH OF LOW PRESSURE WILL REMAIN SITUATED OVER THE EASTERN HALF OF THE CWFA THROUGH MID WEEK. A BACKDOOR FRONT IS PROGGED TO DROP SOUTH OVER MARYLAND AND REMAIN NEARLY STATIONARY THROUGH SATURDAY. THE GFS IS HINTING AT A COUPLE OF MCS SYSTEMS RIDING ALONG A STALLED FRONTAL BOUNDARY OVER PA THROUGH THE FIRST PART OF THE WEEK. THESE TYPE OF SYSTEMS CAN BE HARD TO TIME AND PLACE. USED THE SREFS TO PAINT AREAS WITH THE HIGHEST CHANCES OF POPS THROUGH TUESDAY. ISOLATED/SCATTERED DIURNAL CONVECTION IS EXPECTED THROUGH THE REMAINDER OF THE WEEK. THE ATMOSPHERE SHOULD BE THE MOST UNSTABLE MONDAY AND TUESDAY. A FEW OF THE STORMS COULD REACH SEVERE LIMITS. TUESDAY AND WEDNESDAY ARE STILL LOOKING TO BE THE HOTTEST DAYS OF THE WEEK. TEMPERATURES IN THE MID/UPPER 90S AND NEAR 100 IN SOME SPOTS. HEAT INDICES COULD REACH ADVISORY LEVELS THESE TWO DAYS. AS THE MID LEVEL TROUGH DEVELOPS ALONG THE EAST COAST LATE IN THE WEEK...THE BACKDOOR FRONT TO SLIP SOUTH OVER THE NORTHERN PORTIONS OF THE CWFA. A LITTLE RELIEF FROM THE HEAT WILL BE POSSIBLE. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... FRONT SAGGING SOUTH THROUGH MRB AND NEAR DCA. BEST MOISTURE IS SOUTH OF THIS BOUNDARY...WHERE HAZE EXPECTED TO PERSIST AND BEST SURFACE BASED INSTABILITY WILL BUILD. PRECIPITATION TIMED WITH INCOMING MCV EXPECTED DURING THE LATE AFTERNOON AND EVENING. WILL LIKELY BECOME MORE PESSIMISTIC WITH CHANCES OF CONVECTION BY 18Z TAF PACKAGE. IFR CONDITIONS POSSIBLE WITHIN CONVECTION. DURING THE WORK WEEK...SCATTERED AFTERNOON/EVENING CONVECTION WILL REDUCE CIGS/VSBYS AT THE TERMINAL SITES. LIGHT BR WILL BE LIKELY IN AREAS THAT RECEIVE RAINFALL EACH DAY. && .MARINE... NORTHEAST WIND GUSTS OF 20 KT NORTH OF NORTH BEACH HAVE DISSIPATED. EXPECT WINDS TO VEER TO SOUTHEAST THROUGH THE DAY AROUND 10 KNOTS. THUNDERSTORMS WILL MOVE ACROSS THE WATERS LATE THIS AFTERNOON AND TONIGHT...CAUSING VISIBILITY RESTRICTIONS POSSIBLY BELOW 1 NM AND GUSTY WINDS WHICH COULD REQUIRE SPECIAL MARINE WARNINGS. WINDS SHOULD REMAIN BLO SCA CRITERIA THROUGH THE EXTENDED PERIOD. HOWEVER...SOUTHERLY CHANNELING UP THE BAY IS LIKELY TUESDAY NIGHT. HAVE KEPT THE WINDS ON THE SOUTHERN MARINE ZONE AT 15KT FOR NOW. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...PELOQUIN NEAR TERM...ROGOWSKI SHORT TERM...PELOQUIN LONG TERM...LISTEMAA AVIATION...ROGOWSKI/LISTEMAA MARINE...ROGOWSKI/LISTEMAA
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
947 AM EDT SUN AUG 5 2007 .SYNOPSIS... HIGH PRESSURE OVER THE NORTHEAST WILL GIVE WAY TO AN APPROACHING LOW PRESSURE SYSTEM...CURRENTLY MOVING THROUGH THE OHIO VALLEY. THIS SYSTEM WILL BEGIN TO BRING PRECIPITATION TO PORTIONS OF THE NORTH COUNTRY LATE TONIGHT...OVERSPREADING THE ENTIRE AREA ON MONDAY...BEFORE EXITING MONDAY NIGHT. HIGH PRESSURE RETURNS FOR TUESDAY AND THE NEXT CHANCE FOR ANY RAIN WILL BE TUESDAY NIGHT INTO WEDNESDAY NIGHT. HIGH PRESSURE THEN RETURNS FOR THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED 945 AM SUNDAY INHERITED FCST IN EXCELLENT SHAPE...AND ONLY VERY MINOR ADJUSTMENTS NEEDED...MAINLY TO REMOVE MENTION OF MORNING FOG AND TO BROADEN TEMP RANGES SLIGHTLY ACROSS AREA. LATEST ANALYSIS INDICATES ANOTHER DAY OF OUTSTANDING WX FOR THE NORTH COUNTRY AS SPRAWLING 1020 HPA SFC HIGH PRESSURE BRIDGES ACROSS AREA. VERY DRY COLUMNAR MOISTURE PROFILES WILL ALLOW SUNNY SKIES TO PREVAIL UNDER LIGHT SFC WINDS AND LOW HUMIDITY VALUES. ACARS DATA FROM CYUL/CYOW THIS MORNING SUPPORT MODEL SOLNS ADVERTISING 850 HPA TEMPS TO CLIMB FROM 8-9C THIS MORNING TO 12-14C BY EARLY EVENING. WITH AMPLE BNDRY LYR MIXING...THIS SHOULD ALLOW MAX TEMPS TO CLIMB INTO THE 75-80 DEGREE RANGE AREA WIDE. ENJOY THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... BULK OF RAINFALL EXPECTED ON MONDAY AS LOW/SHORTWAVE PASSES JUST SOUTH OF THE CWA. QPF AMTS STILL CONSISTENT FROM YESTERDAY/S MDL RUNS ATTM SO WILL BUMP UP TO LOW LIKELY POPS FROM CHANCE. WILL ONLY MENTION A CHANCE FOR ANY TS AS EXTENSIVE CLD COVER SHOULD INHIBIT MOST DAYTIME HEATING EFFECTS. THERE WILL BE SOME FURTHER EVENING ENHANCEMENT OF -RW/TRW FOR MUCH OF THE CWA AS FRNT OVER QUEBEC PUSHES IN BEHIND THIS EXITING LOW. SO WILL KEEP HIGH CHANCE POPS OVERNGT AND TAPER INTO THE NE PORTION OF VT AS THIS SYSTEM MVS OFFSHORE AS ANOTHER RIDGE BUILDS OVER AREA FOR TUESDAY. GONE A FEW DEGREES BLW GUIDANCE FOR HIGHS MONDAY DUE TO CLD COVER/PRECIP EXPECTED... AND A FEW HIR IN SPOTS FOR TUESDAY W/ RIDGE EXPECTE DOVER THE AREA. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... NO CHANGES PLANNED FOR THE EXTENDED ATTM. ONLY ISSUE FOR THE EXTENDED WILL BE WAVE ALONG A FRNTL BOUNDARY THAT SETS UP OVER SOUTHERN NEW ENG WEST THRU THE OHIO VALLEY. THIS SHORTWAVE MVS ALONG FRNT TUES NGT INTO WED FOR ANOTHER ROUND OF RW/TRW...THEN OFF SHORE BY WED EVENING. RIDGE SETTING UP TO OUR NORTH WILL KEEP BULK OF RAINFALL SHUNTED SOUTH OF OUR CWA. HIGH PRESSURE RETURNS OVER THE CWA BY LATE WED NGT...SLOWLY MVG SE OFFSHORE BY SATURDAY. THERE IS SLIGHT POTENTIAL FOR A WEAK FROPA SATURDAY AFTNOON...BUT SECOND RIDGE BUILDING SE OUT OF CANADA WILL PUT THE PINCHERS ON THIS FRNT...LIMITING ANY MAJOR PRECIP. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... SFC HIGH PRESSURE BUILDING ACRS FA ALLOWING FOR MAINLY SKC...LGT WNDS TDY...GRDL INCREASE IN CLDS TNGT WITH SOME -SHRA ARRIVING FM W TO E AFT 06Z MON. VFR CONDS SHLD CONT WITH PSBL BRF XCPTNS AT KSLK AND KMPV BTWN 08-11Z MON WITH MVFR-IFR DUE TO PTCLHY FOG. MONDAY THROUGH THURSDAY...RETURN SFC-H8 FLOW ARD HIGH PRS WL ALLOW WARM...MOIST ADVECTION AND SOME MID LVL S/W ACTVTY IN FAST WNW FLOW WL MEAN CHC -SHRA ERLY MON MRNG THRU MON WITH MVFR TO OCNL IFR CONDS PSBL. ANOTHER SFC HIGH PRESSURE IS ANTICIPATED TUESDAY OVER THE REGION WITH MAINLY VFR CONDITIONS...THEN A SURFACE LOW MOVES FROM THE UPPER MIDWEST ACROSS NEW ENGLAND...LEADING TO SHOWERY WEATHER AND MVFR/LOCAL IFR CONDITIONS WEDNESDAY...FOLLOWED ONCE AGIN BY HIGH PRS AND PRIMARILY VFR CONDS FOR THU. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JN NEAR TERM...JMG SHORT TERM...JN LONG TERM...JN AVIATION...SLW
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
1045 AM EDT SUN AUG 5 2007 .SYNOPSIS... HIGH PRESSURE EAST OF THE GREAT LAKES WILL DRIFT TO NEW ENGLAND DURING THE REST OF TODAY...AS A FRONTAL BOUNDARY OVER THE OHIO VALLEY SHIFTS NORTH AS A WARM FRONT. THE FRONT WILL DRIFT SOUTH INTO THE REGION AGAIN ON MONDAY AND SHIFT NORTH ON TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHOWERS WILL RUN INTO THE DRIER AIR OVER NORTHWEST PENNYSLVANIA AND EXTREME NORTHEAST OHIO...SHOWER CHANCES WILL BE LOWER FOR THE AFTERNOON OVER THIS AREA. OVER THE REST OF THE CWA ON GOING SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE EAST...A SLIGHT RISK OF SEVERE THUNDERSTORMS REMAINS OVER WESTERN AREAS OF THE CWA. MORNING TAMDAR DATA DOES INDICATED MORE OF A HEAVY RAIN EVENT AT THE START BUT AIR BECOMES MORE UNSTABLE LATE AFTERNOON OVER THE WESTERN CWA. THE UPDATE WILL BE MORE OF A WORDING CHANGE AND TO LOWER THE HIGHS WITH CLOUD COVER AND RAIN OVER MOST OF THE CWA WITH HIGHS IN THE MID 70S TO THE LOWER 80S. IF THE WARM FRONT MAKES IT FURTHER NORTH THEN INTO THE MID 80S. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... SCATTERED ONGOING CONVECTION TONIGHT AS THE BOUNDARY SINKS SOUTHWARD. MONDAY MIGHT BE A BREAK IN THE SHRA/TS IN THE WAKE OF A STRONGER SHORTWAVE THAT WILL HAVE MOVE EAST ACROSS ONTARIO AND QUEBEC. HIGH PRESSURE WILL PASS TO OUR NORTH. THE BIGGER STORY MONDAY WILL BE THE INCREASE IN TEMPERATURES AND DEWPOINTS. LOWER 90S TEMPS WITH DEWPOINTS MAKING THEIR WAY INTO THE LOWER 70S AS THE MIDWEST HEAT MAKES IT OUR WAY. FOR THE MOST PART AREA CAPPED...ONLY HAVE SLT CHC IN FCST. AGAIN THE FRONT SHIFTS NORTHWARD AND ITS POSSIBLE THAT ANOTHER MCS TYPE COMPLEX COULD AFFECT THE AREA COME TUESDAY MORNING/TUESDAY. A WARM AND MUGGY FEW DAYS. IT APPEARS THAT THE LAST WAVE AND MODULATION OF THIS FRONT WILL BE WEDNESDAY....WITH HIGH PRESSURE MAKING ITS WAY INTO THE NORTHEAST AND ALLOWING FOR A BREAK IN THE 90+ HEAT BY WEEKS END. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... LITTLE CHANGE IN THINKING FOR THE EXTENDED PERIOD FROM YESTERDAY AS THE REGION WILL REMAIN ON THE SOUTHERN EDGE OF THE WESTERLIES WITH A RATHER HOT AND HUMID AIRMASS IN PLACE. THE SOUTHERN EDGE OF THE JET MAY ALLOW WEAK IMPULSES TO CROSS THE AREA FROM TIME TO TIME AND MAY PERMIT A DERECHO TO FORM. TIMING FEATURES IS DIFFICULT SO HAVE KEPT POPS IN THE 20 TO 30 RANGE FOR MOST PERIODS. THE ECMWF AND GFS ARE SOMEWHAT SIMILAR. HIGH TEMPERATURES WILL BE GENERALLY IN THE UPPER 80S TO LOWER OR MID 90S UNTIL NEXT WEEKEND WHEN SLIGHT COOLING IS EXPECTED. GUIDANCE TEMPS ARE LOWER THAN THE 850 TEMPS WOULD GENERALLY INDICATE SO HAVE RAISE TEMPS ABV GFS MEX GUIDANCE. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AREA OF SHOWERS AND EMBEDDED TSTORMS MOVG ESE. APPEARS TO BE A NICE LOW LEVEL JET FEEDING INTO SYSTEM ACROSS N INDIANA. SYSTEM RUNNING INTO VERY DRY AIR ACROSS NE OH/NW PA AND EXPECT AND DIMINISHING IN COVERAGE AND INTENSITY AND WILL USE A TEMPO -SHRA FCST AT CLE YNG AND ERI WITH PREVAILING SHRA ELSEHWERE. ANOTHER ROUND OF SHOWERS AND STORMS SEEMS INEVITABLE FROM THE WEST THIS EVENING AS ATMOSPHERE WILL DESTABILIZE TO THE WEST NEAR HOT UPPER RIDGE AND WILL CONTINUE WITH TSRA FCST TNGT FROM WEST TO EAST. THE EVENING STORMS MAY BE STRONG TO SEVERE MAINLY ACROSS NW OHIO. ATMOSPHERE WILL REALLY MOISTEN UP AS THE WARM FRONT PUSHES NORTH AND THE SHOWERS/STORMS OCCUR AND WILL FCST MVFR FOG/HAZE AT ALL SITES TNGT WITH LOCAL IFR VSBY. COULD BE A BREAK IN THE SHOWERS/STORMS ON MONDAY AND AFTER MORN FOG BURNS OFF SHOULD BE VFR. MORE SHOWERS AND STORMS EXPECTED TUESDAY AS NEXT WEAK WAVE TRACKS EAST ALONG THE FRONT. EARLY MORNING FOG AND A CHANCE OF SHOWERS/STORMS WILL CONT INTO LATE WEEK. WILL PROBABLY TAKE UNTIL LATER THURSDAY OR FRIDAY TO GET FRONT TO SAG FAR ENOUGH SOUTH THAT DRIER/MORE STABLE AIR RETURNS TO THE AREA. && .MARINE... WARM FRONT MOVG N TO NEAR LAKE ERIE TODAY...THEN A WAVE OF LOW PRESSURE WILL TRACK EAST ALONG THE FRONT TONIGHT. THE WEAK FRONT WILL LIKELY REMAIN NEARLY STATIONARY NEAR LAKE ERIE...DRIFTING NORTH AND SOUTH THROUGH MID WEEK...SO THE EXACT WIND DIRECTION DIFFICULT TO PIN DOWN BUT THE GRADIENT SHOULD REMAIN WEAK SO WIND SPEEDS WILL GENERALLY BE LIGHT. A STRONGER FRONT WILL LIKELY PUSH SOUTH ACROSS THE LAKE LATER IN THE WEEK. SOME DISCREPANCIES IN MODELS IN TIMING THE FRONTAL PASSAGE BUT MY HUNCH IS THAT IT WILL PUSH SOUTH ON THURSDAY. SHOWERS AND TSTORMS WILL REMAIN IN THE FORECAST UNTIL THE FRONT PUSHES SOUTH LATER IN THE WEEK. STRONG STORMS POSSIBLE WESTERN LAKE ERIE LATER TODAY AND EARLY TNGT AND PERHAPS THE ENTIRE LAKE ON TUESDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...THOMPSON NEAR TERM...THOMPSON SHORT TERM...OUDEMAN LONG TERM...REL AVIATION...KOSARIK MARINE...KOSARIK
AREA FORECAST DISCUSSION...UPDATED
NWS ABERDEEN SD
1048 AM CDT SUN AUG 5 2007 .UPDATE... STILL WAITING FOR COMPLETE BURN-OFF OF MORNING FOG AND STRATUS...ALTHOUGH THE TREND OVER THE LAST 30 TO 60 MINUTES HAS BEGUN TO SHOW IMPROVEMENT...VISIBILITIES AND CEILINGS SLOWLY LIFTING. NO CHANGE TO MAX T GRID TODAY...ALTHOUGH DID EXTEND SMALL MEASURABLE POPS A BIT FURTHER EASTWARD FOR THIS AFTERNOON AND THIS EVENING...ESPECIALLY ACROSS THE NORTHERN TIER OF ZONES THAT BORDER NORTH DAKOTA. A COLD FRONT NOTED OVER CENTRAL NORTH DAKOTA IS SLIPPING SLOWLY SOUTHWARD AND WILL BE ENCROACHING THE NORTH CENTRAL SODAK ZONES BY LATE THIS AFTERNOON. && .PREV DISCUSSION... .SHORT TERM...TODAY THROUGH MONDAY NIGHT STRATUS DECK REMAINS IN PLACE ACROSS THE ENTIRE EASTERN CWA AND HAS EXPANDED WESTWARD UP TO THE MISSOURI RIVER. BIGGEST FORECAST CHALLENGE FOR TODAY WILL BE TIMING THE EROSION OF CLOUDS AND WHAT EFFECT THIS WILL HAVE ON HIGH TEMPS. TAMDAR AND MODEL SOUNDINGS REVEALING A SHALLOWER CLOUD DECK COMPARED TO YESTERDAY WHICH SHOULD ALLOW FOR A GRADUAL EROSION OF THE CLOUDS BY AFTERNOON ACROSS THE EAST. 925 RH FIELDS SHOW PLENTY OF MOISTURE REMAINING IN PLACE FROM THE JAMES VALLEY AND POINTS EAST THROUGH LATE MORNING. WINDS AT THIS LEVEL THOUGH ARE RATHER LIGHT AND THERE IS NO APPRECIABLE ADVECTION OF DRIER AIR INTO THIS CLOUD LAYER. EROSION WILL MORE THAN LIKELY DEPEND ON SUNSHINE GRADUALLY BREAKING THINGS UP. HIGH TEMPS TODAY RATHER DIFFICULT ACROSS THE EAST SINCE IT ALL DEPENDS ON HOW MUCH CLOUD COVER IS EXPERIENCED IN THIS AREA. FOR NOW...HAVE TEMPS RISING TO THE UPPER 70S TO AROUND 80 OVER THE FAR EAST...WARMING SLIGHTLY INTO THE LOW TO MID 80S OVER THE JAMES VALLEY. CLOUD TRENDS AND TEMPS WILL HAVE TO BE MONITORED CLOSELY THIS MORNING. MORNING FOG WILL BE LEFT IN THE GRIDS AS AREAS EAST OF THE JAMES RIVER ARE AROUND 2SM OR LESS...WHILE MBG/PIR ALSO BEGINNING TO SEE 5SM BR JUST ON THE EDGE OF THE STRATUS DECK. TURNING TO PRECIPITATION...ENERGY ALOFT WILL MOVE ACROSS THE AREA EARLY THIS MORNING AND MODELS TRYING TO GENERATE PRECIP ACROSS SOUTHERN ND. RUC IS EVEN PICKING UP ON SOMETHING MOVING ACROSS THIS AREA. RUC UPPER LEVEL ANALYSIS DOES SHOW A FEW EMBEDDED VORT MAXIMA JUST TO OUR WEST ALONG WITH MODEST LIFT. HAVE INSERTED SLIGHT CHANCE POPS ACROSS THE EXTREME NORTHERN CWA THROUGH THE MORNING HOURS TO ACCOUNT FOR THIS. LEFT SLIGHT CHANCE POPS IN FOR LATER THIS AFTERNOON AS SURFACE TROUGH PUSHES INTO WESTERN SD. BETTER CHANCE FOR STORMS MIGHT REMAIN IN WESTERN SD WHERE BETTER UPSLOPE COMPONENT CAN BE REALIZED. MONDAY STILL LOOKS INTERESTING AS MODELS ARE IN DECENT AGREEMENT IN BRINGING AN AREA OF SHOWERS AND STORMS EASTWARD ACROSS NORTHERN SD/SOUTHERN ND. UPPED POPS SLIGHTLY DURING THE DAY MONDAY. WEST TO EAST FRONTAL BOUNDARY SPLITS STATE IN HALF AND PLACEMENT OF THIS BOUNDARY WILL BE IMPORTANT IN DETERMINING WHERE BEST WAA/LIFT AND ASSOCIATED PRECIP WILL BE. .LONG TERM...TUESDAY THROUGH SATURDAY. BIGGEST CHALLENGE STILL FACING THE LONG TERM IS PRECIPITATION POSSIBILITIES THROUGH THE TIME PERIOD. LATEST ITERATION OF THE MODELS STILL SUGGESTS A MORE ACTIVE WEATHER PATTERN SHAPING UP FOR THE NORTHERN PLAINS...WITH UPPER RIDGE GETTING SURPRESSED SOMEWHAT WITH CWA GETTING INTO A MORE WESTERLY/SW FLOW PATTERN. MODELS ARE STILL HINTING AT SEVERAL FROPAS THROUGH THE TIME PERIOD...BUT DIFFERENCES ARE SETTING UP BETWEEN THE EC/CANADIAN AND GFS. ALSO TIMING DIFFERENCES BETWEEN THE WAVES PUSHING THROUGH ARE LEADING TO A LESS CONFIDENT FORECAST. GFS PCPN FORECAST SEEMS TO BE RULED BY CONVECTIVE FEEDBACK ISSUES...SO LITTLE CONFIDENCE IN THAT SOLN. OPTED TO STAY WITH PERSISTENCE FORECAST...MAKING ONLY COSMETIC CHANGES TO INHERITED WEATHER GRIDS. AS LONG TERM EVOLVES INTO SHORT TERM...WILL BE ABLE TO BETTER FINE TUNE DETAILS. TIMING OF EACH WAVE WILL IMPACT MAX T GRIDS...BASED ON ASSOCIATED CLOUD COVER AND PRECIPITATION. ALSO OPTED TO REMAIN FAIRLY CONSISTENT HERE...TWEAKING INHERITED MAX/MIN T GRIDS. && .AVIATION... THE LIFR AND VLIFR FOG AND STRATUS CONDITIONS EXPERIENCED FOR THE PAST FEW HOURS AT KMBG/KPIR/KATY ARE BEGINNING TO GRADUALLY IMPROVE...AND SHOULD BE ALL BUT A MEMORY BY 18Z TODAY. KATY AND KABR MAY BE DEALING WITH SOME BROKEN IFR/MVFR CEILINGS BETWEEN 600 AND 1500FT AGL A LITTLE BIT LONGER THAN THAT THIS AFTERNOON...BUT THEY SHOULD ALSO BE CLEARING OFF DURING THE AFTERNOON. A CLUSTER OF ELEVATED SHOWERS AND THUNDERSTORMS HAVE FORMED OVER NORTHWEST SOUTH DAKOTA THIS MORNING. THERE IS A GOOD CHANCE THAT THESE SHOWERS AND STORMS WILL CLIP /OR COME PRETTY CLOSE TO/ KMBG TERMINAL AIRSPACE BETWEEN 17Z AND 20Z THIS AFTERNOON. IF THESE SHOWERS AND STORMS CAN HOLD TOGETHER /LOW CONFIDENCE OF OCCURRENCE/ INTO THE LATE AFTERNOON HOURS...OR IF ADDITIONAL SHOWER/THUNDERSTORM ACTIVITY DEVELOPS THIS AFTERNOON...THE KABR AND KATY TERMINALS COULD ALSO BE IMPACTED. WILL CONTINUE TO MONITOR. && .ABR WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. && $$ UPDATE...DORN SHORT TERM...TMT LONG TERM...HINTZ AVIATION...DORN
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
230 PM PDT SUN AUG 5 2007 .SYNOPSIS... THE MARINE LAYER AND ONSHORE FLOW WILL CAUSE LOW CLOUDS AND LOCAL FOG WEST OF THE MOUNTAINS DURING THE NIGHTS AND MORNINGS. LOCAL GUSTY WINDS IN THE MOUNTAINS AND DESERTS DURING THE AFTERNOONS AND EVENINGS. OTHERWISE...DRY SOUTHWEST FLOW ALOFT WILL KEEP THE WEATHER FAIR. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES. .SHORT TERM (TODAY-WED)... STRATUS WAS INTO THE COASTAL AND VALLEY AREAS THIS MORNING AND CLEARED TO JUST OFFSHORE BY NOON. STRATUS REMAINS EXTENSIVE OFFSHORE. EARLY AFTERNOON ACARS SOUNDINGS INDICATE AN INVERSION BASED 2500-3000 FT. ONSHORE GRADIENTS WITH ABOUT 6 MB SAN-IPL. A LITTLE RESIDUAL MID LEVEL MOISTURE COMBINED WITH THERMALS OVER THE MOUNTAINS WILL RESULT IN A FEW CU FOR THE REMAINDER OF THIS AFTERNOON. THE TROUGH OVER THE W WILL CAUSE A GRADUAL DECREASE OF THIS MID LEVEL MOISTURE IN DRY SW FLOW ALOFT THROUGH THE SHORT TERM. EXCEPT LITTLE CHANGE IN THE MARINE LAYER DEPTH TONIGHT WITH LOW CLOUDS AND LOCAL FOG GETTING UP TO THE COASTAL MOUNTAIN SLOPES. THERE MAY BE A LITTLE DECREASE IN MARINE LAYER DEPTH MON AND TUE NIGHTS AS THE UPPER TROUGH WEAKENS. LOW CLOUDS WILL BE SLOW TO CLEAR FROM ALL BEACHES DURING THE AFTERNOONS. MINOR TEMP CHANGES THROUGH TUE THEN A LITTLE UPWARD TREND WED AS LOCAL HEIGHTS INCREASE SLIGHTLY DUE TO THE UPPER HIGH STARTING TO BUILD BACK IN FROM THE E. STRONGER ONSHORE GRADIENTS WILL CAUSE LOCALLY BREEZY TO WINDY CONDITIONS IN THE MOUNTAINS AND DESERTS DURING THE AFTERNOONS AND EVENINGS. .LONG TERM (THU-SUN)... THE UPPER HIGH WILL SLOWLY BUILD BACK OVER THE CENTRAL US AND THE W COAST TROUGH SHIFTS OFFSHORE. DRY SW FLOW ALOFT WILL CONTINUE THROUGH FRI WITH A POSSIBLE RETURN OF MID TO HIGH LEVEL MOISTURE NEXT WEEKEND. THE MARINE LAYER WILL GRADUALLY DECREASE AND THERE WILL BE A SLOW WARMING TREND DURING THE EXTENDED PERIOD. && .AVIATION... 052015Z...MARINE LAYER DEEPENED TO ABOUT 2700-3000 FT. WEAK COASTAL EDDY STILL PRESENT. MORNING STRATUS WAS A LITTLE MORE STUBBORN IN ORANGE CO TIL 1830Z THEN CLEARED AWAY FROM THE COASTLINE. AT 20Z A FEW PATCHES OF STRATUS WERE LINGERING AND REFORMING BETWEEN LA JOLLA AND IMPERIAL BEACH. SOME MORE PATCHES OF STRATUS COULD DEVELOP NEAR THE BEACHES THIS AFTN. EXPECT LOCALLY GUSTY WINDS THIS AFTN AND EVE THRU MTN PASSES INTO ADJACENT DESERT SECTIONS INCLUDING CABAZON TO PALM SPRINGS. CEILINGS SHOULD RETURN TONIGHT ALONG A SIMILAR TIME FRAME AS YESTERDAY...APPROX 01-05Z OVER THE COASTAL AIRPORTS AND SPREADING INLAND TO THE FOOTHILLS BY 08-10Z. BASES AROUND 2000-2300 FT MSL. EXPECT STRATUS TO PUSH INTO KONT AND PORTIONS OF THE INLAND EMPIRE AGAIN BY EARLY MONDAY MORN. VSBY MAINLY ABOVE 7SM BUT SOME 3-5SM HAZE WELL INLAND AND LOCAL FOG WHERE THE CLOUD DECK INTERSECTS THE TERRAIN. ABOVE THE MARINE LAYER...VFR CONDITIONS WITH MOSTLY CLEAR SKIES AND UNRESTRICTED VISIBILITIES THRU MON. && .SGX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ PUBLIC...DVA AVIATION...LAVIS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
312 PM EDT SUN AUG 5 2007 .SYNOPSIS... A FRONTAL BOUNDARY WILL REMAIN NEARLY STATIONARY OVER THE AREA THROUGH TONIGHT...LIFTING NORTHEAST AS A WARM FRONT TOMORROW. HIGH PRESSURE WILL BE THE RULE FOR TUESDAY AND WEDNESDAY. A BACKDOOR FRONT WILL SAG SOUTH INTO THE MID ATLANTIC LATE DURING THE WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... WATER VAPOR LOOP SHOWS A PAIR OF MCVS EMBEDDED IN NORTHWEST FLOW...THE FIRST OVER THE OHIO VALLEY...FOLLOWED BY A MCV OVER CHICAGOLAND. ACARS 400-250MB WIND OBSERVATIONS REVEAL A 90-130KT JET WHICH RIDGES ACROSS THE ROCKIES...AND TROUGHS ACROSS THE CANADIAN MARITIMES. 11Z SURFACE ANALYSIS PLACED A DISSIPATING FRONT FROM THE MIDWEST SOUTHEAST THROUGH THE CAROLINAS. THE MAIN BAROCLINIC ZONE EXTENDS FROM THE MIDWEST SOUTHEAST THROUGH CHICAGO AND NEAR WASHINGTON DC. A 1020MB ANTICYCLONE WAS BUILDING ACROSS NEW ENGLAND. SURFACE BOUNDARY HAS BECOME QUASI STATIONARY AS IT BISECTS THE FORECAST AREA FROM W TO E. INCREASE IN ISENTROPIC LIFT AHEAD OF MCV SHOULD LEAD TO SCATTERED SHOWER AND THUNDERSTORM DEVELOPMENT AHEAD OF THE CONVECTIVE COMPLEX. BEST INSTABILITY IS IMPINGING FROM THE SOUTHEAST ACROSS LOWER SOUTHERN MARYLAND WITH DEW POINTS IN THE MID 70S. ADJUSTED 18Z KIAD RAOB INDICATES LI NEAR -9C...WHICH MATCHES GOES SATELLITE AND RUC ESTIMATES. GIVEN DEGREE OF INSTABILITY...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHEAST FORECAST AREA. DYNAMICAL LIFT WILL BE INCREASING THIS EVENING FROM THE WEST (APPROACHING MCV) WHICH WILL ALLOW FOR ADDITIONAL STORM DEVELOPMENT. CONDITIONS MAY SUPPORT SUPERCELLS. DAMAGING WIND GUSTS ARE THE PRIMARY THREAT. IN ADDITION...PRECIPITABLE WATER VALUES ARE FORECAST TO RISE TO NEAR 2 INCHES...SUPPORTED BY GPS SENSORS IN THE OHIO VALLEY. THIS COULD LEAD TO LOCALLY HEAVY RAINFALL. MOST OF THE ACTIVITY IS EXPECTED TO MOVE TO THE NORTHEAST AFTER MIDNIGHT...WITH PERHAPS SECONDARY DEVELOPMENT ENTERING THE REGION FROM THE OHIO VALLEY LATE TONIGHT. AREAS OF FOG COULD DEVELOP BEHIND CONVECTION. LOWS ARE BASED ON THE 12Z MET GUIDANCE...AND WINDS OFF THE 12Z LWX WRF-ARW. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... FRONTAL BOUNDARY FORECAST TO LIFT TO THE NORTHEAST DURING THE MID MORNING...WITH SKIES BECOMING PARTLY SUNNY WITHIN THE WARM SECTOR. CONVECTIVE CHANCES REVOLVES AROUND STATE AT THE BEGINNING OF THE MORNING...WHETHER OHIO VALLEY STORMS MATERIALIZE AND APPROACH FROM THE NORTHWEST. THIS COULD TRIGGER ADDITIONAL DEVELOPMENT ON THE LEADING EDGE DURING THE MIDDAY AS ACTIVITY MOVES SOUTHEAST. OTHERWISE RIDGING ALOFT WILL BE OCCURRING AND ACTIVITY WILL BE MORE ISOLATED CLOSER TO THE MOUNTAINS. RETURN TO THE HEAT AND HUMIDITY MONDAY. WITH MID LEVEL WARMING...LOWER 90S A GOOD BET...EVEN AFTER MIXING OUT MORNING CLOUDINESS. WITH DEW POINTS NEAR 70F...HEAT INDEX MAY EXCEED 100F. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... NW FLO H5 PATTERN AT BEGINNING OF PD...THEN FLATTENS A BIT MID WEEK BEFORE H5 HIGH PRES GETS ESTABLISHED OVER LOWER TN VALLEY AND NW FLOW PATTERN RETURNS. SFC PATTERN IS A BIT MORE COMPLEX...WITH SFC TROF EXTENDING FROM NE US TO SE US THROUGH MUCH OF THE PERIOD. KEY INTEREST DURING THIS LONG TERM CYCLE IS THE THERMAL RIDGE BOTH THE NAM AND GFS PROGS INTO AREA ON TUE AFT...WITH H85 TEMPS AROUND +23C. THIS EQUATES TO UPPER90S/LOWER 100S WITH FULL SUN. 12Z MAV GIVES IAD AND DCA 100...BWI 99...AND RIC 103. WL BE ENHANCING HWO FOR POTL HEAT ADVSRY/EXCESSIVE HEAT FOR TUE. OTHERWISE...BERMUDA HIGH PRESSURE IS SHUNTED WELL OFFSHORE OF HATTERAS THIS WEEK...REPLACED BY SFC TROFS/LOW PRES. MORE STABLE AIR WILL BE IN PLACE STARTING FRIDAY NIGHT...AND LASTING THROUGH NEXT WEEKEND AS SFC HIGH PRES MAKES WAY TO MID ATLC FROM ONTARIO. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... FIRST MCS DISSIPATED WITH -SHRA AND VCTS EXPECTED ALONG AND AHEAD OF IT. BULK OF ACTIVITY IS ASSOCIATED WITH EASTERN OHIO MCV...TIMED TO ARRIVE DURING THE MID TO LATE EVENING. THIS COULD DROP CEILINGS INTO MVFR IF NOT IFR. LATER TONIGHT...GRADUAL SATURATED ISENTROPIC UPGLIDE UP FRONTAL SLOPE SHOULD PROVIDE AT LEAST POCKETS OF LOW MVFR OR IFR CEILINGS. CEILINGS LIFT THROUGH MVRF-VFR DURING THE MID MORNING WITH LIGHT HAZE. WARM AIRMASS SETTLES INTO THE REGION THIS WORK WEEK. ISOLATED TO SCATTERED DIURNAL CONVECTION EXPECTED TO LOCALLY REDUCE CEILINGS/VISIBILITIES AND PROVIDE LOCALLY HIGHER WIND GUSTS. && .MARINE... VEERING WINDS AS WARM ADVECTION INCREASES TONIGHT. IN ADDITION TO WIDESPREAD SHOWER AND THUNDERSTORMS (SOME MAY BE STRONG ENOUGH TO WARRANT SPECIAL MARINE WARNINGS)...WINDS MAY NEAR SMALL CRAFT CRITERIA IN THE MID BAY OVERNIGHT. GUIDANCE IS CLOSE TO 15 KTS WHICH IS REFLECTED IN THE FORECAST...BUT IF THE APPROACHING STORMS ARE STRONG ENOUGH...SOUTHERN CHANNELING MAY PUSH WINDS INTO SMALL CRAFT CRITERIA. WARM AIRMASS SETTLES INTO THE REGION THIS WORK WEEK. ISOLATED TO SCATTERED DIURNAL CONVECTION EXPECTED TO LOCALLY REDUCE VISIBILITIES AND PROVIDE LOCALLY HIGHER WIND GUSTS AND WAVES. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SYNOPSIS...ROGOWSKI NEAR TERM...ROGOWSKI SHORT TERM...ROGOWSKI LONG TERM...LEE AVIATION...ROGOWSKI MARINE...ROGOWSKI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
153 PM EDT SUN AUG 5 2007 .SYNOPSIS... HIGH PRESSURE OVER THE NORTHEAST WILL GIVE WAY TO AN APPROACHING LOW PRESSURE SYSTEM...CURRENTLY MOVING THROUGH THE OHIO VALLEY. THIS SYSTEM WILL BEGIN TO BRING PRECIPITATION TO PORTIONS OF THE NORTH COUNTRY LATE TONIGHT...OVERSPREADING THE ENTIRE AREA ON MONDAY...BEFORE EXITING MONDAY NIGHT. HIGH PRESSURE RETURNS FOR TUESDAY AND THE NEXT CHANCE FOR ANY RAIN WILL BE TUESDAY NIGHT INTO WEDNESDAY NIGHT. HIGH PRESSURE THEN RETURNS FOR THE END OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPDATED 945 AM SUNDAY INHERITED FCST IN EXCELLENT SHAPE...AND ONLY VERY MINOR ADJUSTMENTS NEEDED...MAINLY TO REMOVE MENTION OF MORNING FOG AND TO BROADEN TEMP RANGES SLIGHTLY ACROSS AREA. LATEST ANALYSIS INDICATES ANOTHER DAY OF OUTSTANDING WX FOR THE NORTH COUNTRY AS SPRAWLING 1020 HPA SFC HIGH PRESSURE BRIDGES ACROSS AREA. VERY DRY COLUMNAR MOISTURE PROFILES WILL ALLOW SUNNY SKIES TO PREVAIL UNDER LIGHT SFC WINDS AND LOW HUMIDITY VALUES. ACARS DATA FROM CYUL/CYOW THIS MORNING SUPPORT MODEL SOLNS ADVERTISING 850 HPA TEMPS TO CLIMB FROM 8-9C THIS MORNING TO 12-14C BY EARLY EVENING. WITH AMPLE BNDRY LYR MIXING...THIS SHOULD ALLOW MAX TEMPS TO CLIMB INTO THE 75-80 DEGREE RANGE AREA WIDE. ENJOY THE DAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/... BULK OF RAINFALL EXPECTED ON MONDAY AS LOW/SHORTWAVE PASSES JUST SOUTH OF THE CWA. QPF AMTS STILL CONSISTENT FROM YESTERDAY/S MDL RUNS ATTM SO WILL BUMP UP TO LOW LIKELY POPS FROM CHANCE. WILL ONLY MENTION A CHANCE FOR ANY TS AS EXTENSIVE CLD COVER SHOULD INHIBIT MOST DAYTIME HEATING EFFECTS. THERE WILL BE SOME FURTHER EVENING ENHANCEMENT OF -RW/TRW FOR MUCH OF THE CWA AS FRNT OVER QUEBEC PUSHES IN BEHIND THIS EXITING LOW. SO WILL KEEP HIGH CHANCE POPS OVERNGT AND TAPER INTO THE NE PORTION OF VT AS THIS SYSTEM MVS OFFSHORE AS ANOTHER RIDGE BUILDS OVER AREA FOR TUESDAY. GONE A FEW DEGREES BLW GUIDANCE FOR HIGHS MONDAY DUE TO CLD COVER/PRECIP EXPECTED... AND A FEW HIR IN SPOTS FOR TUESDAY W/ RIDGE EXPECTE DOVER THE AREA. && .LONG TERM /MONDAY THROUGH SUNDAY/... NO CHANGES PLANNED FOR THE EXTENDED ATTM. ONLY ISSUE FOR THE EXTENDED WILL BE WAVE ALONG A FRNTL BOUNDARY THAT SETS UP OVER SOUTHERN NEW ENG WEST THRU THE OHIO VALLEY. THIS SHORTWAVE MVS ALONG FRNT TUES NGT INTO WED FOR ANOTHER ROUND OF RW/TRW...THEN OFF SHORE BY WED EVENING. RIDGE SETTING UP TO OUR NORTH WILL KEEP BULK OF RAINFALL SHUNTED SOUTH OF OUR CWA. HIGH PRESSURE RETURNS OVER THE CWA BY LATE WED NGT...SLOWLY MVG SE OFFSHORE BY SATURDAY. THERE IS SLIGHT POTENTIAL FOR A WEAK FROPA SATURDAY AFTNOON...BUT SECOND RIDGE BUILDING SE OUT OF CANADA WILL PUT THE PINCHERS ON THIS FRNT...LIMITING ANY MAJOR PRECIP. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... UPDATED 150 PM SUNDAY OVER THE NEXT 24HRS...SFC HIGH PRESSURE IN CONTROL ACROSS FA TODAY ALLOWING FOR MAINLY SKC..LIGHT WINDS AND VFR CONDITIONS. CLOUDS WILL GRADUALLY INCREASE TONIGHT AS THE NEXT SYSTEM APPROACHES FROM THE WEST. RETURN SFC-H8 FLOW AROUND DEPARTING HIGH AND APPROACHING LOW WILL CREATE GUSTY SURFACE WINDS OUT OF THE SOUTH FROM 10-16Z WITH G25KTS AT KBTV POSSIBLE. -SHRA WILL ARRIVE FROM W TO E AFT 10Z MON. MFVR AND SOME IFR WILL BE POSSIBLE AT ALL LOCATIONS FROM 10-18Z DUE TO LOW CIGS AND VISIBILITY IN -SHRA. WINDS AND -SHRA WILL DECREASE IN INTENSITY/COVERAGE BY MID-AFTERNOON. MONDAY THROUGH THURSDAY...CONDITIONS WILL GRADUALLY IMPROVE MONDAY NIGHT AS ANOTHER SFC HIGH PRESSURE IS ANTICIPATED TUESDAY OVER THE REGION WITH MAINLY VFR CONDITIONS...THEN A SURFACE LOW MOVES FROM THE UPPER MIDWEST ACROSS NEW ENGLAND...LEADING TO SHOWERY WEATHER AND MVFR/LOCAL IFR CONDITIONS WEDNESDAY...FOLLOWED ONCE AGAIN BY HIGH PRS AND PRIMARILY VFR CONDS FOR THU. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...JN NEAR TERM...JMG SHORT TERM...JN LONG TERM...JN AVIATION...DUMONT
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
127 PM EDT SUN AUG 5 2007 .SYNOPSIS... HIGH PRESSURE EAST OF THE GREAT LAKES WILL DRIFT TO NEW ENGLAND DURING THE REST OF TODAY...AS A FRONTAL BOUNDARY OVER THE OHIO VALLEY SHIFTS NORTH AS A WARM FRONT. THE FRONT WILL DRIFT SOUTH INTO THE REGION AGAIN ON MONDAY AND SHIFT NORTH ON TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SHOWERS WILL RUN INTO THE DRIER AIR OVER NORTHWEST PENNSYLVANIA AND EXTREME NORTHEAST OHIO...SHOWER CHANCES WILL BE LOWER FOR THE AFTERNOON OVER THIS AREA. OVER THE REST OF THE CWA ON GOING SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE EAST...A SLIGHT RISK OF SEVERE THUNDERSTORMS REMAINS OVER WESTERN AREAS OF THE CWA. MORNING TAMDAR DATA DOES INDICATED MORE OF A HEAVY RAIN EVENT AT THE START BUT AIR BECOMES MORE UNSTABLE LATE AFTERNOON OVER THE WESTERN CWA. THE UPDATE WILL BE MORE OF A WORDING CHANGE AND TO LOWER THE HIGHS WITH CLOUD COVER AND RAIN OVER MOST OF THE CWA WITH HIGHS IN THE MID 70S TO THE LOWER 80S. IF THE WARM FRONT MAKES IT FURTHER NORTH THEN INTO THE MID 80S. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... SCATTERED ONGOING CONVECTION TONIGHT AS THE BOUNDARY SINKS SOUTHWARD. MONDAY MIGHT BE A BREAK IN THE SHRA/TS IN THE WAKE OF A STRONGER SHORTWAVE THAT WILL HAVE MOVE EAST ACROSS ONTARIO AND QUEBEC. HIGH PRESSURE WILL PASS TO OUR NORTH. THE BIGGER STORY MONDAY WILL BE THE INCREASE IN TEMPERATURES AND DEW POINTS. LOWER 90S TEMPS WITH DEW POINTS MAKING THEIR WAY INTO THE LOWER 70S AS THE MIDWEST HEAT MAKES IT OUR WAY. FOR THE MOST PART AREA CAPPED...ONLY HAVE SLT CHC IN FCST. AGAIN THE FRONT SHIFTS NORTHWARD AND ITS POSSIBLE THAT ANOTHER MCS TYPE COMPLEX COULD AFFECT THE AREA COME TUESDAY MORNING/TUESDAY. A WARM AND MUGGY FEW DAYS. IT APPEARS THAT THE LAST WAVE AND MODULATION OF THIS FRONT WILL BE WEDNESDAY....WITH HIGH PRESSURE MAKING ITS WAY INTO THE NORTHEAST AND ALLOWING FOR A BREAK IN THE 90+ HEAT BY WEEKS END. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... LITTLE CHANGE IN THINKING FOR THE EXTENDED PERIOD FROM YESTERDAY AS THE REGION WILL REMAIN ON THE SOUTHERN EDGE OF THE WESTERLIES WITH A RATHER HOT AND HUMID AIRMASS IN PLACE. THE SOUTHERN EDGE OF THE JET MAY ALLOW WEAK IMPULSES TO CROSS THE AREA FROM TIME TO TIME AND MAY PERMIT A DERECHO TO FORM. TIMING FEATURES IS DIFFICULT SO HAVE KEPT POPS IN THE 20 TO 30 RANGE FOR MOST PERIODS. THE ECMWF AND GFS ARE SOMEWHAT SIMILAR. HIGH TEMPERATURES WILL BE GENERALLY IN THE UPPER 80S TO LOWER OR MID 90S UNTIL NEXT WEEKEND WHEN SLIGHT COOLING IS EXPECTED. GUIDANCE TEMPS ARE LOWER THAN THE 850 TEMPS WOULD GENERALLY INDICATE SO HAVE RAISE TEMPS ABV GFS MEX GUIDANCE. && .AVIATION /17Z SUNDAY THROUGH THURSDAY/... WARM FRONT NEAR A FWA TO CMH LINE. FRONT WILL LIFT NORTH OF AREA THIS EVENING...AS LOW PRESSURE NOW IN IOWA MOVES INTO SE LOWER MICHIGAN BY MIDNIGHT LOCAL. THE LOW WILL THEN MOVE NE OF THE FORECAST AREA OVERNIGHT. WHAT DOES THAT MEAN....RAIN SHOWERS WITH PREDOMINATELY MVFR CONDITIONS (EXCEPT FOR THE PATCHY IFR CIGS NEAR THE WARM FRONT) WILL COME TO AN END EARLY THIS EVENING. THEN EXPECT SCATTERED TSRA TO DEVELOP WEST OF THE FORECAST AREA TOWARD 00Z...AND MOVE THROUGH THE FORECAST AREA TONIGHT. EXPECT MVFR BR TOMORROW MORNING...WHICH SHOULD BURN OFF MY MID MORNING. MORE SHOWERS AND STORMS EXPECTED TUESDAY AS NEXT WEAK WAVE TRACKS EAST ALONG THE FRONT. EARLY MORNING FOG AND A CHANCE OF SHOWERS/STORMS WILL CONT INTO LATE WEEK. WILL PROBABLY TAKE UNTIL LATER THURSDAY OR FRIDAY TO GET FRONT TO SAG FAR ENOUGH SOUTH THAT DRIER/MORE STABLE AIR RETURNS TO THE AREA. && .MARINE... WARM FRONT MOVG N TO NEAR LAKE ERIE TODAY...THEN A WAVE OF LOW PRESSURE WILL TRACK EAST ALONG THE FRONT TONIGHT. THE WEAK FRONT WILL LIKELY REMAIN NEARLY STATIONARY NEAR LAKE ERIE...DRIFTING NORTH AND SOUTH THROUGH MID WEEK...SO THE EXACT WIND DIRECTION DIFFICULT TO PIN DOWN BUT THE GRADIENT SHOULD REMAIN WEAK SO WIND SPEEDS WILL GENERALLY BE LIGHT. A STRONGER FRONT WILL LIKELY PUSH SOUTH ACROSS THE LAKE LATER IN THE WEEK. SOME DISCREPANCIES IN MODELS IN TIMING THE FRONTAL PASSAGE BUT MY HUNCH IS THAT IT WILL PUSH SOUTH ON THURSDAY. SHOWERS AND TSTORMS WILL REMAIN IN THE FORECAST UNTIL THE FRONT PUSHES SOUTH LATER IN THE WEEK. STRONG STORMS POSSIBLE WESTERN LAKE ERIE LATER TODAY AND EARLY TNGT AND PERHAPS THE ENTIRE LAKE ON TUESDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN SHORT TERM...OUDEMAN LONG TERM...REL AVIATION...DJB MARINE...KOSARIK
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
347 PM CDT SUN AUG 5 2007 .SHORT TERM...TONIGHT THROUGH MONDAY. WEAK SFC WAVE LOCATED NEAR MSN THIS AFTERNOON WILL CONTINUE TO TRAVERSE FRONTAL BOUNDARY ACROSS SOUTHERN WI THIS EVENING AND WEAKEN. OTHER THAN A FEW ISOLATED SHOWERS AND SPRINKLES ASSOIATED WITH THIS FEATURE VERY LITTLE IN THE WAY OF PRECIP ANYWHERE ACROSS THE STATE. MORNING GRB SOUNDING AND EARLY AFT TAMDAR SOUNDINGS AT RHI...CWA AND ATW INDICATED FAIRLY DEEP SURFACE-BASED MOIST LAYER TO 700 MB. THUS LOW-CLOUDS/PATCHY DRIZZLE HAVE BEEN VERY STUBBORN ACROSS THE FORECAST AREA. SOME BREAKS/THINNING IN THE OVERCAST FINALLY OCCURING UPSTREAM ACROSS NORTHWEST AND WESTCENRAL WISCONSIN IN REGION OF STRONGER SUBSIDENCE AND SHALLOWER MOISTURE. MODELS SUGGEST THAT OVERALL TREND WILL BE FOR LOW CLOUDS TO CONTINUE TO ERODE DURING THE LATE AFTERNOON AS AS DRIER AIR FILTERS IN. HOWEVER...NOT AS CONFIDENT ON SKIES COMPLETELY CLEARING OUT AFTER MIDNIGHT GIVEN DEPTH OF LOW-LEVEL MOISTURE. DEGREE OF CLEARING OVENIGHT WILL ALSO AFFECT HOW MUCH FOG WILL DEVELOP AS WELL. OPTED TO CONTINUE TO MENTION AREAS OF FOG ACROSS THE ENTIRE FORECAST AREA FOR TONIGHT GIVEN AMOUNT OF BLYR MOISTURE AVAILABLE AND LIGHT VARIABLE WINDS EXPECTED. WEAK HI PRES WILL BUILD SLIDE ACROSS THE FORECAST AREA ON MONDAY. SHOULD BE A FAIR AMOUNT OF SUNSHINE AT LEAST DURING THE FIRST HALF OF THE DAY...FOLLOWED BY AN INCREASE IN CLOUDS DURING THE AFTERNOON AS LOW PRESSURE APPROACHED FROM THE EASTERN DAKOTAS. SFC WARM FRONT WILL BEGIN TOMAKE A MOVE BACK NORTHWARD INTO AT LEAST THE SOUTHWEST PORTION OF THE FCST AREA DURING THE AFTERNOON. IT APPEARS THAT BEST DYNAMICS/WAA WILL HOLD OFF UNTIL AFTER 00Z...THUS BACKED OFF FURTHER AND REMOVED MENTION OF PRECIP OVER ALL FCST AREA FOR THE AFTERNOON. 850 TEMPS AND ADEQUATE MIXING SUGGEST MID TO UPPER 80S FOR MUCH OF HE FORECAST AREA FOR TUESDAY. .LONG TERM...MONDAY NIGHT THRU SUNDAY. FCST CHALLENGE DEALING WITH TIMING AND COVERAGE OF MAINLY TWO PROGGED S/WS TRACKING OVER THE REGION MONDAY NIGHT INTO TUESDAY AND THEN AGAIN WEDNESDAY INTO THURSDAY. TO FURTHER COMPLICATE THE FCST CHALLENGE...A FRONTAL BOUNDARY CURRENTLY EXTENDING FROM SE NEBRASKA TO FAR SOUTHERN WISCONSIN TO LOWER MICHIGAN SEPARATES A MOIST AIRMASS WITH PW/S NEAR 2.00 G/KG TO THE SOUTH...FROM A DRIER AIRMASS TO THE NORTH. THE INTERACTION OF THESE PROGGED S/WS WITH RESPECT TO THE BOUNDARY PROVIDE SOME POTENTIAL OF DECENT RAINFALL TO MAINLY SOUTHERN PORTIONS OF THE STATE NEAR THE HIGHER PWS. MODELS RUNS MAY NEED ANOTHER RUN OR TWO TO LATCH ONTO NRN EXTENT OF MORE EXTENSIVE RAIN AREA...AND UNTIL SO WILL TEND FCST WITH A DRY BIAS ESPECIALLY OVER THE DRY NORTH AND NORTHEAST. IN ADDITION...SINCE THESE WAVES TEND TO PASS WITHIN A 12 TO 18 HOUR PERIOD...WILL PROVIDE SOME DRY SEPARATION BETWEEN THE SYSTEMS. FOR THE FIRST WAVE...LATEST CONSENSUS MODEL TIMING APPEARS TO BE LATER MONDAY NIGHT INTO EARLY TUESDAY. MODELS ARE ATTEMPTING TO CONCENTRATE PCPN IN TWO MAIN REGIONS...NEAR THE BEST HEIGHT FALLS OVER LAKE SUPERIOR AND THEN NEAR THE DEEPER MOISTURE AND FRONTAL BOUNDARY OVER SOUTHERN WISCONSIN. SURFACE WAVE DEVELOPMENT WILL NEED TO BE MONITORED MONDAY FOR PCPN POTENTIAL. FOR THE SECOND WAVE...GFS MAY HAVE SOME CONVECTIVE FEEDBACK EARLY WEDNESDAY...OTHERWISE READJUSTED CHC POPS FOR THIS SECOND WAVE WITH THE BEST CONSENSUS HEIGHT FALLS FROM LATE WEDNESDAY INTO THURSDAY. AGAIN FRONTAL BOUNDARY POSITION WILL PLAY A ROLE ON THE AMNTS. SURFACE HIGH PRESSURE SYSTEM BUILDS INTO THE REGION LATE IN THE WEEK AND INTO THE WEEKEND. A FEW MODELS ATTEMPTING TO DRAG A COLD FRONT INTO THE STATE TOWARD SUNDAY...BUT WILL LEAVE DRY AT THIS TIME SINCE UPPER HEIGHTS PROGGED TO INCREASE. NO CHANGE FROM GOING FCST TEMPS THIS WEEK...LIKE TODAY (SUNDAY) ANY LINGERING CLOUDS FROM A DEPARTED SYSTEM MAY TEND TO HOLD AFTN TEMPS DOWN. && .AVIATION...PRIMARY FSCT CONCERN OVERNIGHT WILL BE DEGREE OF CLEARING OF LOW CLOUDS ACROSS THE FCST AREA. ALTHOUGH MODELS SUGGEST SUBSIDENCE...FAIRLY PROGRESSIVE DRYING AND SOME CLEARING FROM WEST TO EAST OVERNIGHT...OBSERVED AIRCRAFT SOUNDINGS ACROSS CENTRAL AND NORTHERN WI SUGGEST FAIRLY DEEP SURFACE-BASED MOISTURE THAT MAY BE DIFFICULT TO REMOVE BEFORE SUNSET. ASSUMING SOME CLEARING AND FAILRY DEEP MOISTURE STILL IN PLACE...AREAS OF FOG WITH IFR CONDITIONS STILL LIKELY ACROSS MUCG OF THE FORECAST AREA AFTER MIDNIGHT...FOLLOWED BY IMPROVING CONDTIONS AFT 14Z MONDAY. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ ESB/TDH