AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TALLAHASSEE FL 900 PM EDT TUE AUG 2 2005 .SYNOPSIS...LATEST WATER VAPOR/RUC80 H5 COMPOSITE SHOWS THE PERSISTENT SHEAR AXIS OVER THE CWFA WEDGED BETWEEN RIDGES TO THE NW AND SE. A SERIES OF PASSING DISTURBANCES ALOFT AROUND THE PERIPHERY OF THE RIDGE TO THE SE COMBINED WITH A MOIST TROPICAL AIRMASS (PRECIP WATER VALUES ABOVE 2") PRODUCED WIDESPREAD SHRA/TSRA OVER THE CWFA AGAIN TODAY. THIS ACTIVITY HAS KEPT TEMPS COOLER THAN NORMAL, WITH HIGHS IN THE 80S. AS WAS THE CASE MONDAY EVENING, COVERAGE AND INTENSITY HAS DIMINISHED, WITH THE BULK OF THE ACTIVITY CONFINED TO AREAS ALONG AND E OF I-75. OTHERWISE, SKIES ARE MOSTLY CLOUDY TO CLOUDY AND PREVAILING WINDS ARE LIGHT NELY. && .SHORT TERM UPDATE...BASED ON RADAR TRENDS, WILL AMEND ZONES TO LOWER POPS TO SLIGHT CHANCE FOR THE REST OF TONIGHT. && .MARINE UPDATE...WINDS AT THE C-MAN/BUOYS HAVE VEERED FROM WLY TO NLY. SPEEDS ARE AROUND 5 KTS AND SEAS ARE 2 FT OR LESS. BOTH THE ETA AND RUC INDICATE WINDS BECOMING VARIABLE OVERNIGHT, AND WILL TREND IN THAT DIRECTION. WILL LOWER PRECIP COVERAGE TO SCATTERED. && .AVIATION...SHRA/TSRA PRESENTLY DISSIPATING ACROSS THE AREA THIS EVENING. WENT WITH PERSISTENCE ON VSBYS/CIGS FOR THE OVERNIGHT PERIOD. CONDITIONS WILL SLOWLY IMPROVE TO MVFR/VFR AFT 12Z...HOWEVER SHRA/TSRA WILL AGAIN DEVELOP AT PFN BY 14Z AND 16Z-18Z ELSEWHERE. && .TAE WATCHES/WARNINGS/ADVISORIES... AL...NONE. GA...NONE. FL...NONE. && $$ PUBLIC/MARINE...JAMSKI AVIATION...SHAFER fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 1049 AM MDT TUE AUG 2 2005 .UPDATE... BASED ON 16Z OBS AT ITR...LOOKS LIKE WINDS COMING UP FASTER AND STRONGER THAN PREVIOUSLY EXPECTED AND LOOKS LIKE FREQUENT GUSTS UP TO 30 MPH APPEAR LIKELY ACROSS PORTIONS OF EASTERN COLORADO THROUGH THE AFTERNOON. RH ALREADY AT 18 PERCENT AND EXPECT IT TO FALL BELOW THE CRITICAL 15 PERCENT THROUGH MUCH OF THE AFTERNOON...THEREFORE ISSUED A RED FLAG WARNING FOR CHEYENNE AND KIT CARSON COUNTIES. NEW GRIDS WILL BE OUT SHORTLY AND WILL TWEAK WIND SPEEDS IN ZFP A BIT TO MATCH CURRENT THINKING. && .PREV DISCUSSION... (ISSUED 918 AM MDT TUE AUG 2 2005) DISCUSSION... MAIN FORECAST CONCERNS CENTER AROUND HEAT...FIRE WX POTENTIAL AND ISOLATED THUNDER CHANCES LATE. BOTH 12Z ETA AND RUC RATHER SIMILAR THIS MORNING WITH SFC PATTERN AND REMAIN CLOSE TO EACH OTHER'S SOLUTIONS THROUGH THE AFTERNOON. BIG DIFFERENCES AS USUAL BETWEEN RUC/ETA DEWPOINT FIELD HOWEVER. 12Z SOUNDINGS AT LBF AND DEN WOULD INDICATE LOTS OF POTENTIAL FOR DRY AIR TO MIX DOWN TO THE SFC...AND ETA'S SOUNDINGS FOR SOME REASON KEEPS MOISTURE UP DESPITE DRY AIR ALOFT. ONLY PLACE WHERE SFC MOISTURE MAY NOT MIX OUT IS IN THE SOUTHEAST WHERE KDDC 12Z SOUNDING INDICATES A BIT MORE LOW LEVEL MOISTURE TO WORK WITH. END RESULT IS AFTERNOON RH VALUES DIPPING INTO THE RED FLAG WARNING CRITERIA. HOWEVER IT APPEARS STRONGEST WINDS ALOFT ARE BEFORE 18Z...AND WHILE WINDS WILL INCREASE DURING THE AFTERNOON...DONT THINK WERE GOING TO GET WINDS INTO THE 25 MPH RANGE AS H700 MB WINDS ONLY AROUND 20KTS DURING PEAK HEATING...BUT WILL BE MONITORING CHEYENNE AND KIT CARSON COUNTY CLOSELY FOR FIRE WX POTENTIAL. MOST OF THE CWA'S MAX TEMPS LOOK ON TRACK...BUT AM A LITTLE CONCERNED THAT CLOUD DECK SLIDING SOUTHEAST ACROSS NEBRASKA MAY HAMPER WARMING A BIT IN THE KMCK AREAS AND POSSIBLY AS FAR SOUTH AS KHLC. KNOCKED A FEW DEGREES OF GOING MAXES TO ACCOUNT FOR THIS. SFC TEMPS AND AFTERNOON HEAT INDICES WILL APPROACH ADVISORY LEVELS ACROSS THE EXTREME EASTERN CWA...BUT MORNING LOWS TODAY AND TOMORROW SHOULD KEEP US FROM MAINTAINING OVERNIGHT LOW REQUIREMENT FOR ADVISORY. FINALLY SLIM THUNDER CHANCES FOR THIS AFTERNOON WILL BE THE LAST CONCERN BOTH ETA/RUC DEVELOP PERSISTENT AREA OF DEEP CONVERGENCE ACROSS NORTHERN AND EASTERN CWA. HOWEVER THINK ETAS CAPE FORECAST A BIT OVERDONE DUE TO AFOREMENTIONED DEWPOINT PROBLEM. DECIDED TO SPEED UP AND EXPAND ISOLATED POP AREA SLIGHTLY ACROSS NORTHWEST CWA...AS EASTERN PORTION OF CONVERGENCE ZONE WILL LIKELY REMAIN CAPPED. GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. $$ && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...RED FLAG WARNING UNTIL 6 PM TUESDAY FOR COZ091-COZ092. && $$ ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 918 AM MDT TUE AUG 2 2005 .DISCUSSION... MAIN FORECAST CONCERNS CENTER AROUND HEAT...FIRE WX POTENTIAL AND ISOLATED THUNDER CHANCES LATE. BOTH 12Z ETA AND RUC RATHER SIMILAR THIS MORNING WITH SFC PATTERN AND REMAIN CLOSE TO EACH OTHER'S SOLUTIONS THROUGH THE AFTERNOON. BIG DIFFERENCES AS USUAL BETWEEN RUC/ETA DEWPOINT FIELD HOWEVER. 12Z SOUNDINGS AT LBF AND DEN WOULD INDICATE LOTS OF POTENTIAL FOR DRY AIR TO MIX DOWN TO THE SFC...AND ETA'S SOUNDINGS FOR SOME REASON KEEPS MOISTURE UP DESPITE DRY AIR ALOFT. ONLY PLACE WHERE SFC MOISTURE MAY NOT MIX OUT IS IN THE SOUTHEAST WHERE KDDC 12Z SOUNDING INDICATES A BIT MORE LOW LEVEL MOISTURE TO WORK WITH. END RESULT IS AFTERNOON RH VALUES DIPPING INTO THE RED FLAG WARNING CRITERIA. HOWEVER IT APPEARS STRONGEST WINDS ALOFT ARE BEFORE 18Z...AND WHILE WINDS WILL INCREASE DURING THE AFTERNOON...DONT THINK WERE GOING TO GET WINDS INTO THE 25 MPH RANGE AS H700 MB WINDS ONLY AROUND 20KTS DURING PEAK HEATING...BUT WILL BE MONITORING CHEYENNE AND KIT CARSON COUNTY CLOSELY FOR FIRE WX POTENTIAL. MOST OF THE CWA'S MAX TEMPS LOOK ON TRACK...BUT AM A LITTLE CONCERNED THAT CLOUD DECK SLIDING SOUTHEAST ACROSS NEBRASKA MAY HAMPER WARMING A BIT IN THE KMCK AREAS AND POSSIBLY AS FAR SOUTH AS KHLC. KNOCKED A FEW DEGREES OF GOING MAXES TO ACCOUNT FOR THIS. SFC TEMPS AND AFTERNOON HEAT INDICES WILL APPROACH ADVISORY LEVELS ACROSS THE EXTREME EASTERN CWA...BUT MORNING LOWS TODAY AND TOMORROW SHOULD KEEP US FROM MAINTAINING OVERNIGHT LOW REQUIREMENT FOR ADVISORY. FINALLY SLIM THUNDER CHANCES FOR THIS AFTERNOON WILL BE THE LAST CONCERN BOTH ETA/RUC DEVELOP PERSISTENT AREA OF DEEP CONVERGENCE ACROSS NORTHERN AND EASTERN CWA. HOWEVER THINK ETAS CAPE FORECAST A BIT OVERDONE DUE TO AFOREMENTIONED DEWPOINT PROBLEM. DECIDED TO SPEED UP AND EXPAND ISOLATED POP AREA SLIGHTLY ACROSS NORTHWEST CWA...AS EASTERN PORTION OF CONVERGENCE ZONE WILL LIKELY REMAIN CAPPED. && .PREV DISCUSSION...FORECAST CONCERNS ARE HIGH TEMPERATURES TODAY AND TOMORROW ALONG WITH THE POSSIBILITY OF THUNDERSTORMS WEDNESDAY NIGHT. NOT MUCH DIFFERENCE IN GUIDANCE OR TRENDS OVER THE PAST FEW DAYS OR BETWEEN MODELS SO WILL ONLY MAKE MINOR CHANGES TO ONGOING FORECAST. HAVE TENDED TOWARDS THE WARMER NAM NUMBERS IN THE SHORT TERM GIVEN THE STRONG RIDGE IN PLACE AND THE HOT TEMPERATURES OVER THE PAST COUPLE DAYS. THE UPPER RIDGE FLATTENS ON WEDNESDAY AS A TROUGH MOVES THROUGH CENTRAL CANADA AND THE NORTHERN TIER OF THE U.S. THIS WILL DRAG A FRONT THROUGH THE FORECAST AREA OVERNIGHT WEDNESDAY FOR HIGH TEMPERATURES 15 TO 20 DEGREES COOLER ON THURSDAY THAN ON WEDNESDAY. SCATTERED THUNDERSTORMS ARE EXPECTED BEHIND THE FRONT AS AN UPPER VORT MAX MOVES EAST OF THE ROCKIES OVERNIGHT WEDNESDAY. WILL KEEP THE REMAINDER OF THE FORECAST DRY AS THE UPPER ENERGY STAYS NORTH OF THE REGION AND TEMPERATURES REBOUND BACK INTO THE 90S AS THE UPPER RIDGE REBUILDS OVER THE WESTERN U.S. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ JRM/LOCKHART ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 947 PM EDT TUE AUG 2 2005 .UPDATE... IR SAT AND RADAR IMAGERY SHOW ISOLATED CONVECTION...WHICH DEVELOPED THIS AFTERNOON PRIMARILY OVER HIGH TERRAIN WEST OF THE BLUE RIDGE...HAS CEASED WITH THE LOSS OF BOUNDARY LAYER HEATING EARLY THIS EVENING. 00Z DULLES SOUNDING INDICATES A PW VALUE OF 1.55 INCHES...WHILE THE UPSTREAM SOUNDING AT PITTSBURGH YIELDED A PW VALUE OF 1.22 WITH A NOTICEABLY DRIER LOWER PORTION OF THE SOUNDING FROM THE SFC TO H8. FLOW AROUND THE SFC AND H85 HIGH PRESSURE CENTERS IN THE LOWER OH VALLEY WILL MAINTAIN A GENERALLY NORTHWEST FLOW ACROSS THE NORTHERN MID ATLANTIC. THIS FLOW SHOULD ADVECT SLIGHTLY DRIER AIR ACROSS THE REGION TONIGHT. HOWEVER...WITH 01Z SFC DEWPOINTS IN THE UPPER 60S AND LOWER 70S...THERE WILL BE SOME LIGHT FOG FORMATION...MAINLY GROUND FOG...AFTER MIDNIGHT WEST OF THE BLUE RIDGE ACROSS THE AREAS WHICH WERE AFFECTED BY FOG TUESDAY MORNING. LOWS ACROSS THE CWA LOOK ON TRACK THIS EVENING WITH LOWS EXPECTED OVERNIGHT FROM THE MID 60S TO LOWER 70S. WILL UPDATE ZONES TO REMOVE MENTION OF EVENING SHOWERS AND THUNDERSTORMS ACROSS THE WESTERN HALF OF THE CWA. && .PREVIOUS DISCUSSION...235 PM EDT TUE AUG 2 2005... SHORT TERM (TONIGHT THROUGH WEDNESDAY)... VISIBLE SATELLITE IMAGERY SHOWS A DECENT CU/SCU FIELD ACROSS MUCH OF OUR CWA THIS AFTERNOON...DEVELOPING ON THE PERIPHERY OF LOW LEVEL HIGH PRESSURE CENTERED NEAR MANSFIELD OH. AREAL OBSERVATIONS SUPPORT THIS WITH LOTS OF SCT040-060. WATER VAPOR IMAGERY EVEN SHOWS A LITTLE UPPER LEVEL SPIN IN SOUTHERN VA...HOWEVER NEITHER THIS SPIN NOR THE CU/SCU ARE PRODUCING ANY PRECIP ATTM. THE CLOSEST SHOWERS AT 18Z WERE IN SOUTH CENTRAL PA...AND SEEMED TO BE HAVING TROUBLE MAINTAINING THEMSELVES. STILL BELIEVE A COUPLE OF STRAY TERRAIN CIRCULATION CELLS MAY WANDER ABOUT ACROSS OUR WESTERN CWA FROM MID AFTERNOON THROUGH THIS EVENING. WILL CONTINUE WITH THE SLGT CHC EVENING POPS ACROSS THIS AREA. IT IS WORTH NOTING THAT THE GFS AND RUC ARE TRYING TO DEVELOP SOME QPF OVER OTHER PARTS OF OUR CWA...AND EVEN SHOW A SECONDARY RELATIVE MAXIMUM OF INSTABILITY (CAPE) AFTER SUNSET. WE/RE NOT BUYING INTO THIS...AS ANY INFLUENCE FROM THE UPPER SPIN SHOULD REMAIN SOUTH OF OUR CWA AND ANY SURVIVING CONVECTION TO OUR NORTH SHOULD REMAIN JUST THAT...AND FIZZLE AFTER THE SUN SETS. THUS...AM KEEPING THE REST OF THE CWA DRY TONIGHT. WEDNESDAY...NOT MUCH DIFFERENT THAN TUESDAY WITH PLENTY OF INSTABILITY AND SOME MOISTURE TOO...BUT LACKING A GOOD TRIGGER AND/OR UPPER LEVEL SUPPORT TO GOAD CONVECTION INTO INITIATING. CU WILL DEVELOP AGAIN AS CONVECTIVE TEMPERATURES ARE MET...AND A STRAY CELL IN THE WEST WILL PROMPT SLGT CHC POPS IN ROUGHLY THE SAME PLACE AS THIS EVENING/S POPS. DEWPOINTS MAY BE A TAD HIGHER TODAY...WITH TEMPS IN THE LOWER TO MIDDLE 90S. HEAT INDICES IN THE METRO AREAS ARE FORECAST JUST UNDER HEAT ADVISORY CRITERIA. WILL ISSUE SPS REGARDING HEAT/HUMIDITY. LONG TERM (WEDNESDAY NIGHT THROUGH TUESDAY)... THE EXTENDED FORECAST STILL REVOLVES AROUND THE FRONTAL BOUNDARY FOR LATE FRIDAY AND INTO THE WEEKEND. RIDGING IN PLACE IN THE MID LEVELS FOR WEDNESDAY THROUGH EARLY FRIDAY. BY LATE FRIDAY...THE RIDGE BEGINS TO BREAK DOWN AS A TROUGH AND ASSOCIATED SHORTWAVE MOVE EAST OVER THE GREAT LAKES AND OHIO RIVER VALLEY. THE MAIN ENERGY ASSOCIATED WITH THE TROUGH STAYS WELL TO THE NORTH OF THE CWFA. THE WEAK TROUGHING CONTINUES THROUGH THE WEEKEND...BUT THE FLOW TURNS MORE ZONAL FOR THE FIRST PART OF NEXT WEEK. HIGH PRESSURE GENERALLY IN CONTROL THROUGH THE END OF THE WEEK. HOWEVER...THE ETA AND GFS ARE PROGGING A WEAK LEE TROUGH ON THURSDAY. THE FRONTAL BOUNDARY BEGINS APPROACHING THE WESTERN CWFA BY LATE FRIDAY...AND WILL CONTINUE TO MOVE SLOWLY SOUTH OVER THE CWFA THROUGH EARLY SUNDAY. BOTH THE ETA AND GFS ARE SIMILAR WITH THEIR SOLUTIONS...AND STALL THE BOUNDARY ANYWHERE FROM THE SOUTHERN PORTION OF THE CWFA TO SOUTHERN VIRGINIA. THE FRONT IS PROGGED TO BECOME DIFFUSE BY EARLY MONDAY. HIGH PRESSURE WILL BUILD BACK IN FOR THE FIRST PART OF NEXT WEEK. OVERALL...THE MODELS ARE IN GOOD AGREEMENT AND MOS IS PRETTY CLUSTERED. HEAT INDICES WILL RANGE IN THE MID TO UPPER 90S DURING THE DAY THURSDAY...MAINLY IN THE METROPOLITAN AREAS. WILL ISSUE AN SPS HIGHLIGHTING THE HEAT INDICES...AND WILL HOLD OFF ISSUING A HEAT ADVISORY FOR NOW. AVIATION... VFR UNTIL LATER AT NIGHT...WHEN VISIBILITIES CAN DROP INTO MVFR/IFR IN FOG BEFORE IMPROVING BACK TO VFR BY 14Z. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SHORT TERM/AVIATION...PELOQUIN LONG TERM...LISTEMAA UPDATE...SMITH md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 235 PM EDT TUE AUG 2 2005 .SHORT TERM (TONIGHT THROUGH WEDNESDAY)... VISIBLE SATELLITE IMAGERY SHOWS A DECENT CU/SCU FIELD ACROSS MUCH OF OUR CWA THIS AFTERNOON...DEVELOPING ON THE PERIPHERY OF LOW LEVEL HIGH PRESSURE CENTERED NEAR MANSFIELD OH. AREAL OBSERVATIONS SUPPORT THIS WITH LOTS OF SCT040-060. WATER VAPOR IMAGERY EVEN SHOWS A LITTLE UPPER LEVEL SPIN IN SOUTHERN VA...HOWEVER NEITHER THIS SPIN NOR THE CU/SCU ARE PRODUCING ANY PRECIP ATTM. THE CLOSEST SHOWERS AT 18Z WERE IN SOUTH CENTRAL PA...AND SEEMED TO BE HAVING TROUBLE MAINTAINING THEMSELVES. STILL BELIEVE A COUPLE OF STRAY TERRAIN CIRCULATION CELLS MAY WANDER ABOUT ACROSS OUR WESTERN CWA FROM MID AFTERNOON THROUGH THIS EVENING. WILL CONTINUE WITH THE SLGT CHC EVENING POPS ACROSS THIS AREA. IT IS WORTH NOTING THAT THE GFS AND RUC ARE TRYING TO DEVELOP SOME QPF OVER OTHER PARTS OF OUR CWA...AND EVEN SHOW A SECONDARY RELATIVE MAXIMUM OF INSTABILITY (CAPE) AFTER SUNSET. WE/RE NOT BUYING INTO THIS...AS ANY INFLUENCE FROM THE UPPER SPIN SHOULD REMAIN SOUTH OF OUR CWA AND ANY SURVIVABLE CONVECTION TO OUR NORTH SHOULD REMAIN JUST THAT...AND FIZZLE AFTER THE SUN SETS. THUS...AM KEEPING THE REST OF THE CWA DRY TONIGHT. WEDNESDAY...NOT MUCH DIFFERENT THAN TUESDAY WITH PLENTY OF INSTABILITY AND SOME MOISTURE TOO...BUT LACKING A GOOD TRIGGER AND/OR UPPER LEVEL SUPPORT TO GOAD CONVECTION INTO INITIATING. CU WILL DEVELOP AGAIN AS CONVECTIVE TEMPERATURES ARE MET...AND A STRAY CELL IN THE WEST WILL PROMPT SLGT CHC POPS IN ROUGHLY THE SAME PLACE AS THIS EVENING/S POPS. DEWPOINTS MAY BE A TAD HIGHER TODAY...WITH TEMPS IN THE LOWER TO MIDDLE 90S. HEAT INDICES IN THE METRO AREAS ARE FORECAST JUST UNDER HEAT ADVISORY CRITERIA. WILL ISSUE SPS REGARDING HEAT/HUMIDITY. && .LONG TERM (WEDNESDAY NIGHT THROUGH TUESDAY)... THE EXTENDED FORECAST STILL REVOLVES AROUND THE FRONTAL BOUNDARY FOR LATE FRIDAY AND INTO THE WEEKEND. RIDGING IN PLACE IN THE MID LEVELS FOR WEDNESDAY THROUGH EARLY FRIDAY. BY LATE FRIDAY...THE RIDGE BEGINS TO BREAK DOWN AS A TROUGH AND ASSOCIATED SHORTWAVE MOVE EAST OVER THE GREAT LAKES AND OHIO RIVER VALLEY. THE MAIN ENERGY ASSOCIATED WITH THE TROUGH STAYS WELL TO THE NORTH OF THE CWFA. THE WEAK TROUGHING CONTINUES THROUGH THE WEEKEND...BUT THE FLOW TURNS MORE ZONAL FOR THE FIRST PART OF NEXT WEEK. HIGH PRESSURE GENERALLY IN CONTROL THROUGH THE END OF THE WEEK. HOWEVER...THE ETA AND GFS ARE PROGGING A WEAK LEE TROUGH ON THURSDAY. THE FRONTAL BOUNDARY BEGINS APPROACHING THE WESTERN CWFA BY LATE FRIDAY...AND WILL CONTINUE TO MOVE SLOWLY SOUTH OVER THE CWFA THROUGH EARLY SUNDAY. BOTH THE ETA AND GFS ARE SIMILAR WITH THEIR SOLUTIONS...AND STALL THE BOUNDARY ANYWHERE FROM THE SOUTHERN PORTION OF THE CWFA TO SOUTHERN VIRGINIA. THE FRONT IS PROGGED TO BECOME DIFFUSE BY EARLY MONDAY. HIGH PRESSURE WILL BUILD BACK IN FOR THE FIRST PART OF NEXT WEEK. OVERALL...THE MODELS ARE IN GOOD AGREEMENT AND MOS IS PRETTY CLUSTERED. HEAT INDICES WILL RANGE IN THE MID TO UPPER 90S DURING THE DAY THURSDAY...MAINLY IN THE METROPOLITAN AREAS. WILL ISSUE AN SPS HIGHLIGHTING THE HEAT INDICES...AND WILL HOLD OFF ISSUING A HEAT ADVISORY FOR NOW. && .AVIATION... VFR UNTIL LATER AT NIGHT...WHEN VISIBILITIES CAN DROP INTO MVFR/IFR IN FOG BEFORE IMPROVING BACK TO VFR BY 14Z. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SHORT TERM...PELOQUIN LONG TERM...LISTEMAA AVIATION... MARINE... md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC 1102 AM EDT TUE AUG 2 2005 .SHORT TERM (REST OF TODAY)... CURRENT FORECAST IS IN DECENT SHAPE AND WON/T BE MAKING MANY CHANGES. MORNING FOG HAS DISSIPATED...LEAVING MOSTLY SUNNY TO PARTLY CLOUDY SKIES ACROSS OUR CWA AS SURFACE HIGH PRESSURE CENTERS ITSELF OVER WEST VIRGINIA. THE 12Z KIAD RAOB SHOWS A LOT OF INSTABILITY...WITH HIGH CAPES AND NEGATIVE LI/S. HOWEVER...DO NOT DETECT A SIGNIFICANT LIFTER TO TAKE ADVANTAGE OF THE INSTABILITY. THE EXCEPTION TO THIS WOULD BE ACROSS THE WEST WHERE TERRAIN INDUCED CONVECTION REMAINS POSSIBLE. WILL HAVE TO KEEP AN EYE ON THE UPPER LEVEL FEATURE ACROSS SOUTHERN VA...AS IT COULD ATTEMPT TO WREAK HAVOC WITH CURRENT FORECAST OF ONLY SLGT CHC POPS ACROSS THE WEST. AM CONCERNED ABOUT THE QPF FIELDS EVIDENT IN THE LATEST RUC (SHOWING EVENING PRECIP OUTSIDE OF WHERE OUR WESTERN POPS RESIDE). WILL CLOSELY SCRUTINIZE FOR THE AFTERNOON PACKAGE. PRODUCTS OUT VERY SOON. && .AVIATION... HAZE MAY BRING TERMINALS TO MVFR FOR A TIME...OTHERWISE VFR THROUGH TODAY WITH POSSIBLE MVFR/IFR FOG AGAIN LATER TONIGHT/EARLY WEDNESDAY. && .MARINE... NO FLAGS ON THE WATERS. WINDS WILL FAVOR A WESTERLY COMPONENT UNTIL AT LEAST MID AFTERNOON...BEFORE POSSIBLY GOING MORE SOUTHERLY. && .PREVIOUS DISCUSSION... (ISSUED 315 AM EDT TUE AUG 2 2005) SHORT TERM (TDA/TNGT)... RLTVLY PLSNT WX FOR ERLY AUG - HIGH PRES FIRMLY PLANTED OVER THE MID ATLC RGN...DWPTS 65-70..TEMPS REACHING L90S E OF THE MTNS. THINK THERE COULD BE A FEW TSTMS PSBL OVR THE FAR WRN MTNS THIS AFTN. HV BEEN WATCHING OB AT MRB BOUNCING UP AND DOWN BTWN 1-3SM...AND WL CONT TO MONITOR THE MTNS RGNS THRU SUNRISE...AND ISSUEA STMT IF VSBYS DROP THRUT THAT AREA. NO WORRIES TNGT - HIGH RMS OVR THE AREA SO SHOULD BE A REPEAT OF NOW. WOODY! LONG-TERM (WED-MON) RIDGE BUILDS EWD THIS WEEK FROM THE OH/MS VALLEYS BRINGING HOT TEMPS ONCE AGAIN WITH ISOLD CONVECTION POSSIBLE W OF THE BLUE RIDGE WED-THU. UPPER TROF OVR THE UPPER MIDWEST THU MOVES TO THE ERN GRT LKS BY FRI WHILE WEAKENING. ASSOCIATED CDFNT LOOKS AS IT WILL GET ENOUGH PUSH TO CLEAR AT LEAST THE NORTHERN HALF OF THE FCST AREA. LOOKS LIKE ANOTHER POSSIBLE ROUND OF STRONG/SVR TSRA LATE FRI AFTERNOON/EVENING LIKE WE HAD LAST WEEK. WEAK FRONT STALLS SOMEWHERE IN VA SAT THEN DISSIPATES BY MON WITH RETURN FLOW AND TYPICAL MID-SUMMER WX. ROSA AVIATION...LGT FOG WL REDUCE VSBY THRU SUNRISE AND AGN TUE NGT. MARINE...NO FLAGS. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...NONE. VA...NONE. WV...NONE. MARINE...NONE. && $$ SHORT TERM/AVIATION/MARINE...PELOQUIN PREV DISCUSSION...WOODY!/ROSA md AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 1115 AM EDT TUE AUG 2 2005 UPDATED NEAR TERM AND LONG TERM .2ND MORNING UPDATE... PREVIOUS FORECAST LOOKS ON TRACK AND AM NOT PLANNING TO MAKE ANY CHANGES TODAY. WEAK FRONTAL BOUNDARY WASHING OUT MAY RESULT IN ISOLATED TO WIDELY SCATTERED THUNDERSTORMS GENERALLY ALONG AND SOUTH OF THE MASSACHUSETTS TURNPIKE FROM MID AFTERNOON INTO THE EVENING. GFS AND RUC SHOWS QPF IN THIS REGION...WHILE THE NGM AND NAM DO NOT SHOW ANY QPF BECAUSE OF LESS SURFACE CONVERGENCE. CUMULUS BEGINNING TO DEVELOP IN THIS REGION THOUGH AND AFTERNOON CAPES BETWEEN 1000 AND 2000 J/KG WITH SURFACE DEWPOINTS IN THE MID TO UPPER 60S. AGAIN...AREAL COVERAGE THIS AFTERNOON AND EVENING SHOULD NOT BE THAT LARGE BUT DEFINITELY THE THREAT FOR A BIT OF CONVECTION. WINDS ALOFT ARE GENERALLY 30 KNOTS OR LESS SO SEVERE POTENTIAL WILL BE LIMITED...ALTHOUGH AN ISOLATED SEVERE STORM CAN NOT BE RULED OUT. OTHER CONCERN WILL BE THE MORE WIDESPREAD CONVECTION THAT WILL DEVELOP ACROSS NORTHERN NEW ENGLAND THIS AFTERNOON. THIS ACTIVITY MAY PROPAGATE SOUTHEASTWARD WITH NORTHWEST FLOW OVERNIGHT. ALTHOUGH WE TEND NOT TO GET A LOT OF NOCTURNAL CONVECTION IN NEW ENGLAND...WHEN WE HAVE NORTHWEST FLOW THERE TENDS TO BE A GREATER RISK AS WE SAW LAST NIGHT. FOR NOW WILL NOT MAKE ANY CHANGES TONIGHT UNTIL WE GET TO LOOK AT ALL THE 12Z MODEL DATA...BUT THE NAM MODEL HINTS AT THIS SCENARIO FRANK/WAS .LONG TERM (SATURDAY THROUGH TUESDAY)... NOT AS WARM AND HUMID THIS WEEKEND STILL APPEARS TO BE IN THE CARDS FOR SOUTHERN NEW ENGLAND...AS COLD FRONT EXITS S.CST SOMETIME SAT. AGAIN...BEHIND THE FRONT NOT AS WARM AND HUMID WEATHER WILL OVERSPREAD THE REGION LATER SAT AND SUN...AS WEAK HIGH PRES BUILDS EAST FROM THE GREAT LAKES. BY MON...THE FRONT OFFSHORE WASHES OUT AND MODEST HEIGHT RISES BEGIN ACROSS THE NORTHEAST...AS THE SHORT WAVE RIDGE APPROACHES FROM THE WEST. SOUTHWEST FLOW WILL THEN DEVELOP MON AND TUE...TRANSPORTING HEAT AND HUMIDITY BACK INTO THE REGION. AS FOR MODEL OF CHOICE THIS PERIOD...00Z GFS APPEARS TO BE THE OUTLIER HERE...AS IT IS THE ONLY MODEL (AND CAN GLOB TO A LESSER EXTENT) THAT BRINGS THE POLAR VORTEX FROM N.CNTRL CANADA ALL THE WAY SOUTH TO HUDSON BAY BY LATE MON. 00Z ECMWF/UKMET AND NCEP ENSEMBLES ALL KEEP POLAR VORTEX FARTHER FARTHER N...YIELDING A LESS AMPLIFIED NORTHERN BRANCH JET ACROSS THE CANADIAN-U.S. BORDER THIS PERIOD. REGARDING HPC GUID...AFTER COLLABORATING WITH SURROUNDING OFFICES WE WILL LOWER POPS SAT AND LIMIT ANY CHC POPS TO SRN ZNS GIVEN PROXIMITY TO SFC FNT. FOR SUN...WILL KEEP THE ENTIRE REGION DRY AS FNTL BNDRY MOVES OFSHR OR PERHAPS EVEN WASHES OUT. OTHERWISE... FOLLOWED HPC GUID CLOSELY. && .PREVIOUS DISCUSSION... (ISSUED 913 AM EDT TUE AUG 2 2005) MORNING UPDATE... FORECAST ON TRACK BUT NEW SET OF GRIDS/ZONE HAVE BEEN SENT. BASICALLY WENT WITH SUNNY SKIES THROUGH EARLY AFTERNOON AS NO CUMULUS HAS FORMED YET. ALSO...SET POPS TO ZERO THROUGH 17Z AS NOT EXPECTING ANY CONVECTION TO FIRE BEFORE THEN. MORE LATER. FRANK --------------------------------------------------------------------- PREVIOUS DISCUSSION SHORT TERM (TODAY THROUGH WEDNESDAY)... MODELS ARE IN DECENT AGREEMENT TODAY SYNOPTICALLY...BUT THINKING IS MOS IS TOO LOW WITH THE POPS LATER TODAY. A DISSIPATING COLD FRONT PUSHING SOUTH ACROSS SOUTHERN NEW ENGLAND THIS MORNING EXPECTED TO PROVIDE A FOCUS FOR MORE SHOWERS AND THUNDERSTORMS THIS AFTERNOON. WITH DEW POINTS IN THE LOWER TO MID 60S...AND A SHORTWAVE GRAZING OUR REGION TO THE NORTH...WILL GO WITH AT LEAST A SLIGHT CHANCE OF AFTERNOON CONVECTION. GREATEST THREAT WILL BE ALONG THE BOUNDARY ACROSS THE SOUTHERN HALF OF MA...RI AND NORTHEAST CT. DRIER WEATHER TONIGHT INTO WEDNESDAY AS HIGH PRESSURE TRIES TO BUILD INTO OUR REGION FROM THE OHIO VALLEY. A WEAK BACK DOOR COLD FRONT MAY ALSO KICK OFF SOME SHOWERS WEDNESDAY AFTERNOON...BUT WITH LOWER DEW POINTS FEEL THIS IS LESS LIKELY THAN TODAY. GUIDANCE TEMPERATURES LOOK REASONABLE. LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)... WARM AND INCREASINGLY HUMID EARLY IN THE LONG TERM. UPPER RIDGE OVER THE REGION WEDNESDAY NIGHT SHIFTS EAST LATER THURSDAY...WITH THE RESULTING CHANGE TO A WESTERLY UPPER FLOW PUSHING A WARM FRONT THROUGH NEW ENGLAND. MOISTURE PROFILES LOOK DRY ENOUGH FOR MOSTLY CLEAR SKIES WEDNESDAY NIGHT INTO PART OF THURSDAY...THEN A PERIOD OF CLOUDS THURSDAY AS THE WARM FRONT MOVES THROUGH. TEMPERATURES THURSDAY AND FRIDAY LOOK HOT. TEMPS ALOFT THURSDAY ARE FORECAST TO CLIMB TO 16-18C BY AFTERNOON...SUPPORTIVE OF UPPER 80S TO LOWER 90S. FRIDAY TEMPS ALOFT ARE FORECAST AT 18-20C...SUPPORTING LOW-MID 90S. FRIDAY IS THE MOST ACTIVE DAY OF THE REMAINDER OF THE WEEK. A COLD FRONT WILL MOVE THROUGH THE GREAT LAKES...REACHING THE ST LAWRENCE VALLEY EARLY FRIDAY MORNING...AND MOVING ACROSS NEW ENGLAND LATE FRI AND FRIDAY NIGHT. LIFTED INDICES TURN SUBZERO FRIDAY WITH WINDS TURNING MORE SOUTHWEST DURING THE DAY. WILL FORECAST CHANCE OF THUNDERSTORMS FRIDAY AFTERNOON INTO FRIDAY NIGHT. SATURDAY THROUGH MONDAY REMAINS UNCHANGED. AVIATION... MOSTLY VFR CONDITIONS EXPECTED TODAY...AT LEAST ONCE THE POCKETS OF IFR CEILINGS AND VISIBILITY IN MORNING FOG DISSIPATE. SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED THIS AFTERNOON...WITH MVFR CONDITIONS. VFR CONDITIONS EXPECTED TO RETURN OVERNIGHT TO MOST OF THE REGION...EXCEPT MVFR CONDITIONS IN AREAS OF FOG ONCE AGAIN LATE TONIGHT. MARINE... GENERALLY LIGHT WINDS AND SEAS EXPECTED TODAY THROUGH WEDNESDAY. SOME 5 FOOT SEAS POSSIBLE...MAINLY IN THE OUTER WATERS...IN THE INCREASING SOUTHWEST FLOW AHEAD OF THE APPROACHING COLD FRONT. OTHERWISE WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW HEADLINE LEVELS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...NONE. && $$ LONG TERM...NOCERA ma AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE TAUNTON MA 1111 AM EDT TUE AUG 2 2005 .2ND MORNING UPDATE... PREVIOUS FORECAST LOOKS ON TRACK AND AM NOT PLANNING TO MAKE ANY CHANGES TODAY. WEAK FRONTAL BOUNDARY WASHING OUT MAY RESULT IN ISOLATED TO WIDELY SCATTERED THUNDERSTORMS GENERALLY ALONG AND SOUTH OF THE MASSACHUSETTS TURNPIKE FROM MID AFTERNOON INTO THE EVENING. GFS AND RUC SHOWS QPF IN THIS REGION...WHILE THE NGM AND NAM DO NOT SHOW ANY QPF BECAUSE OF LESS SURFACE CONVERGENCE. CUMULUS BEGINNING TO DEVELOP IN THIS REGION THOUGH AND AFTERNOON CAPES BETWEEN 1000 AND 2000 J/KG WITH SURFACE DEWPOINTS IN THE MID TO UPPER 60S. AGAIN...AREAL COVERAGE THIS AFTERNOON AND EVENING SHOULD NOT BE THAT LARGE BUT DEFINITELY THE THREAT FOR A BIT OF CONVECTION. WINDS ALOFT ARE GENERALLY 30 KNOTS OR LESS SO SEVERE POTENTIAL WILL BE LIMITED...ALTHOUGH AN ISOLATED SEVERE STORM CAN NOT BE RULED OUT. OTHER CONCERN WILL BE THE MORE WIDESPREAD CONVECTION THAT WILL DEVELOP ACROSS NORTHERN NEW ENGLAND THIS AFTERNOON. THIS ACTIVITY MAY PROPAGATE SOUTHEASTWARD WITH NORTHWEST FLOW OVERNIGHT. ALTHOUGH WE TEND NOT TO GET A LOT OF NOCTURNAL CONVECTION IN NEW ENGLAND...WHEN WE HAVE NORTHWEST FLOW THERE TENDS TO BE A GREATER RISK AS WE SAW LAST NIGHT. FOR NOW WILL NOT MAKE ANY CHANGES TONIGHT UNTIL WE GET TO LOOK AT ALL THE 12Z MODEL DATA...BUT THE NAM MODEL HINTS AT THIS SCENARIO FRANK/WAS -------------------------------------------------------------------- .MORNING UPDATE... FORECAST ON TRACK BUT NEW SET OF GRIDS/ZONE HAVE BEEN SENT. BASICALLY WENT WITH SUNNY SKIES THROUGH EARLY AFTERNOON AS NO CUMULUS HAS FORMED YET. ALSO...SET POPS TO ZERO THROUGH 17Z AS NOT EXPECTING ANY CONVECTION TO FIRE BEFORE THEN. MORE LATER. FRANK --------------------------------------------------------------------- PREVIOUS DISCUSSION .SHORT TERM (TODAY THROUGH WEDNESDAY)... MODELS ARE IN DECENT AGREEMENT TODAY SYNOPTICALLY...BUT THINKING IS MOS IS TOO LOW WITH THE POPS LATER TODAY. A DISSIPATING COLD FRONT PUSHING SOUTH ACROSS SOUTHERN NEW ENGLAND THIS MORNING EXPECTED TO PROVIDE A FOCUS FOR MORE SHOWERS AND THUNDERSTORMS THIS AFTERNOON. WITH DEW POINTS IN THE LOWER TO MID 60S...AND A SHORTWAVE GRAZING OUR REGION TO THE NORTH...WILL GO WITH AT LEAST A SLIGHT CHANCE OF AFTERNOON CONVECTION. GREATEST THREAT WILL BE ALONG THE BOUNDARY ACROSS THE SOUTHERN HALF OF MA...RI AND NORTHEAST CT. DRIER WEATHER TONIGHT INTO WEDNESDAY AS HIGH PRESSURE TRIES TO BUILD INTO OUR REGION FROM THE OHIO VALLEY. A WEAK BACK DOOR COLD FRONT MAY ALSO KICK OFF SOME SHOWERS WEDNESDAY AFTERNOON...BUT WITH LOWER DEW POINTS FEEL THIS IS LESS LIKELY THAN TODAY. GUIDANCE TEMPERATURES LOOK REASONABLE. && .LONG TERM (WEDNESDAY NIGHT THROUGH MONDAY)... WARM AND INCREASINGLY HUMID EARLY IN THE LONG TERM. UPPER RIDGE OVER THE REGION WEDNESDAY NIGHT SHIFTS EAST LATER THURSDAY...WITH THE RESULTING CHANGE TO A WESTERLY UPPER FLOW PUSHING A WARM FRONT THROUGH NEW ENGLAND. MOISTURE PROFILES LOOK DRY ENOUGH FOR MOSTLY CLEAR SKIES WEDNESDAY NIGHT INTO PART OF THURSDAY...THEN A PERIOD OF CLOUDS THURSDAY AS THE WARM FRONT MOVES THROUGH. TEMPERATURES THURSDAY AND FRIDAY LOOK HOT. TEMPS ALOFT THURSDAY ARE FORECAST TO CLIMB TO 16-18C BY AFTERNOON...SUPPORTIVE OF UPPER 80S TO LOWER 90S. FRIDAY TEMPS ALOFT ARE FORECAST AT 18-20C...SUPPORTING LOW-MID 90S. FRIDAY IS THE MOST ACTIVE DAY OF THE REMAINDER OF THE WEEK. A COLD FRONT WILL MOVE THROUGH THE GREAT LAKES...REACHING THE ST LAWRENCE VALLEY EARLY FRIDAY MORNING...AND MOVING ACROSS NEW ENGLAND LATE FRI AND FRIDAY NIGHT. LIFTED INDICES TURN SUBZERO FRIDAY WITH WINDS TURNING MORE SOUTHWEST DURING THE DAY. WILL FORECAST CHANCE OF THUNDERSTORMS FRIDAY AFTERNOON INTO FRIDAY NIGHT. SATURDAY THROUGH MONDAY REMAINS UNCHANGED. && .AVIATION... MOSTLY VFR CONDITIONS EXPECTED TODAY...AT LEAST ONCE THE POCKETS OF IFR CEILINGS AND VISIBILITY IN MORNING FOG DISSIPATE. SCATTERED SHOWERS AND THUNDERSTORMS EXPECTED THIS AFTERNOON...WITH MVFR CONDITIONS. VFR CONDITIONS EXPECTED TO RETURN OVERNIGHT TO MOST OF THE REGION...EXCEPT MVFR CONDITIONS IN AREAS OF FOG ONCE AGAIN LATE TONIGHT. && .MARINE... GENERALLY LIGHT WINDS AND SEAS EXPECTED TODAY THROUGH WEDNESDAY. SOME 5 FOOT SEAS POSSIBLE...MAINLY IN THE OUTER WATERS...IN THE INCREASING SOUTHWEST FLOW AHEAD OF THE APPROACHING COLD FRONT. OTHERWISE WINDS AND SEAS ARE EXPECTED TO REMAIN BELOW HEADLINE LEVELS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...NONE. && $$ MORNING UPDATE...FRANK/WAS SHORT TERM...BELK LONG TERM...WTB ma AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 1030 PM EDT TUE AUG 2 2005 .UPDATE... MAIN FCST CONCERNS OVERNIGHT ARE SHRA/TSRA TRENDS/STRENGTH. WV IMAGERY AND RUC ANALYSIS INDICATED A PROMINENT MID/UPPER LEVEL RDG OVER THE CNTRL PLAINS RESULTING IN WSW FLOW FROM THE NRN PLAINS IN WRLY FLOW FROM THE NRN PLAINS INTO THE WRN GRT LAKES. ONE UPSTREAM SHRTWV EXTENDING FROM WRN ONTARIO AND THE MN ARROWHEAD TO WRN UPR MI SUPPORTED AN AREA OF SHRA AND ISOLD TSRA FROM WRN LK SUPERIOR INTO W UPR MI. AT THE SFC...SRLY FLOW PREVAILED ACRS THE REGION BTWN A RDG OVER THE UPPER OH VALLEY AND A TROF OVER THE CNTRL DAKOTAS. EXPECT SHRA/TSRA OVER W UPPER MI WILL BE AIDED BY DEVELOPING MODEST LLJ WITH W AND THEN CNTRL UPR MI ON NOSE OF 925-850 MB SW WIND OF 25-30 KT...PER 00Z NAM/RUC. WHILE MUCAPE VALUES TO NEAR 1500 J/KG MAY STILL SUPPORT SOME STRONGER TSTMS...WEAK SHEAR WOULD GIVE MAINLY UNORGANIZED PULSE-TYPE STORMS. MOISTENING MID LVLS...PER 00Z KMPX/KINL SNDGS WILL LOWER RISK OF WET MICROBURSTS COMPARED TO MORE FAVORABLE PROFILE FARTHER TO THE EAST. SO...UPDATED WILL INCLUDE SCT SHRA/TSRA AT LEAST THROUGH CNTRL UPR MI WITH MORE ISOLD PCPN OVER THE E CWA...AWAY FROM FOCUS OF THE LOW LEVEL INFLOW. ALTHOUGH LOW LVL WINDS ARE FAVORABLE FOR ADDITIONAL TSRA DEVELOPMENT OVER W UPR MI...PER RADAR TRENDS...EXPECT LULL IN PCPN OVER THE W AFTER MIDNIGHT AS UPSTREAM CONVECTION OVER CNTRL MN HAS FADED. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ JLB mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 1012 PM EDT TUE AUG 2 2005 .UPDATE.... A STRONG SUBTROPICAL RIDGE OVER THE CENTRAL US AND HIGH PRESSURE CENTERED JUST SOUTH OF THE AREA WILL KEEP SE MICHIGAN PRECIP FREE TONIGHT. SHOULD JUST SEE SOME CIRRUS ADVANCING INTO THE REGION FROM THE NORTH FROM TIME TO TIME. BASED ON THE LATEST TRENDS... CURRENT TEMP FORECAST LOOKS ON TARGET. IT WILL BE A RATHER MUGGY NIGHT WITH DEWPOINTS RANGING FROM THE MID 60S TO LOWER 70S. THIS LOW LEVEL MOISTURE WILL RESULT IN SOME FOG. DO NOT THINK WE WILL RADIATE TOO MUCH WITH SOME LIGHT SW WINDS... SO NOT EXPECTING VISIBILITY TO DROP BELOW 2 MILES. THUS THE GOING FORECAST LOOKS ON TARGET SO NO UPDATES WILL BE MADE. && .AVIATION... ISSUED AT 716 PM. SURFACE HIGH PRESSURE ANCHORED OVER THE SOUTHERN GREAT LAKES WILL MOVE SOUTH TONIGHT INTO WEDNESDAY. BASED ON CURRENT DEWPOINTS...18Z MODEL SOUNDINGS AND LATEST TAMDAR SOUNDINGS OUT OF DTW... SOUTHWESTERLY RETURN FLOW HAS ALREADY ADVECTED HIGHER LOW LEVEL MOISTURE INTO SE MICHIGAN. TAMDAR SOUNDINGS INDICATE THE MOISTURE PROFILE STEADY TO SLIGHTLY INCREASING THROUGH THE LOWEST 2K FEET. THIS MAY BE ABLE TO ALLOW SOME MVFR VISIBILITIES IN FOG/HAZE TO DEVELOP LATE TONIGHT INTO EARLY WED MORNING... MUCH LIKE WHAT WAS OBSERVED THIS MORNING ACROSS IL AND SW LOWER MI. OTHERWISE... EXPECT VFR CONDITIONS THROUGH THE REST OF THE TAF PERIOD AS THE BEST FOCUS FOR CONVECTION SHOULD REMAIN ACROSS THE NORTHERN GREAT LAKES INTO WED AFTERNOON. && .SHORT TERM...TONIGHT AND WEDNESDAY SURFACE AND UPPER LEVEL RIDGE IS IN PLACE THROUGH MOST OF THIS SHORT TERM FORECAST PERIOD. A SMALL CONVECTIVE CLUSTER WAS PROGRESSING EAST-SOUTHEAST ACROSS CENTRAL MINNESOTA AND CURRENT THICKNESS SCHEMES POINT TOWARD THIS ACTIVITY DIVING SOUTHEAST AWAY FROM THE GREAT LAKES REGION. WHILE WE COULD OBSERVE SOME CI/CS FROM THIS ACTIVITY LATE TONIGHT INTO WEDNESDAY... DO NOT EXPECT ANY ADDITIONAL FEATURES TO PRECLUDE A MOSTLY CLEAR SKY. IN FACT... LATEST H2O VAPOR LOOP SHOWS A WEAK SHORT WAVE CROSSING THE THUMB THIS AFTERNOON WITH PLENTY OF DRY AIR SEEN ACROSS SOUTHERN LAKE MICHIGAN INTO SOUTHERN LOWER MICHIGAN FOR A DRY TONIGHT. AS RIDGE SLOWLY SLIDES TO THE EAST ON WEDNESDAY... INCREASING SOUTHWEST FLOW SHOULD ADVECT NOT ONLY WARMER TEMPERATURES... BUT THE DEWPOINTS AS WELL. TRAJECTORIES ORIGINATE FROM ILLINOIS WHERE SOME MIST (BR) WAS OBSERVED THIS MORNING AND CURRENT TEMPERATURES INTO THE LOWER 90S. MACHINE NUMBERS HAVE RISEN A FEW DEGREES WITH MAINLY MIDDLE 90S AND WE WILL RAISE TEMPERATURES ACCORDINGLY. DEWPOINTS HAVE DROPPED BACKED INTO THE MIDDLE AND UPPER 60S ACROSS THIS REGION AND TRANSPORT INTO THE GREAT LAKES WOULD BRING HEAT INDICES CLOSE TO THE CENTURY MARK...BUT NOT ENOUGH TO WARRANT HEADLINES AT THIS POINT. AS WITH LAKE BREEZE DEVELOPMENT AND COINCIDING WITH CONVECTIVE POTENTIAL... WITH INCREASING SOUTHWEST FLOW IN THE AFTERNOON AND WARMING TEMPERATURES ALOFT... PREFER TO KEEP IT DRY AT THE PRESENT TIME. BUT IF 925-950MB WINDS ARE LESS THAN FORECAST... AS SUGGESTED IN THE RUC13 AND MM5... THEN THE THUMB COULD SEE SOME ADDITIONAL CONVERGENCE AND A SLIGHT CHANCE FOR CONVECTION. GIVEN UPSTREAM CURRENT CONDITIONS WITH A LAKE BREEZE AND NOT MUCH CU... CURRENT THOUGHTS ARE TO REMAIN DRY. && .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY FIRST PROBLEM OF THE FORECAST WILL BE TIMING/EXTENT OF SHOWER AND THUNDERSTORM CHANCES THURSDAY INTO THURSDAY NIGHT. NAM HAS EASED OFF ITS FASTER SOLUTION TODAY...AND HAS THE SAME BASIC IDEA AS GFS. BASICALLY...A SHORTWAVE DRIVING THE FRONT INTO LOWER MICHIGAN BY MIDDAY AND THEN ANOTHER TRAILING SHORTWAVE...WHICH WORKS TO HOLD PRECIPITATION CHANCES INTO THE EVENING HOURS OR THURSDAY. CURRENT FORECAST REALLY HAS THIS SCENARIO PRETTY WELL IN HAND AND PLAN NO MAJOR CHANGES. THE NEXT MAJOR QUESTION IN THE FORECAST COMES TOWARD THE END OF THE FORECAST AS A MORE ZONAL FLOW...OR EVEN BROAD UPPER TROF SETS UP OVER THE NORTHERN TIER OF STATES. ALTHOUGH DETAILS VERY A GREAT DEAL AS WOULD BE EXPECTED THAT FAR OUT...THE GENERAL MODEL PROGS SUPPORT THIS FLOW...WHICH SHOULD PUT THE GREAT LAKES INTO A MORE ACTIVE WEATHER PATTERN (IN RELATION TO THE DOMINATE HIGH PRESSURE EXPECTED OVER THE WEEKEND). PLAN ON ADDING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE MONDAY AND TUESDAY TIMEFRAME BASED ON THIS. AS FOR TEMPERATURES...THURSDAY WILL BE RATHER DIFFICULT TO NAIL DOWN EXACTLY AS TIMING OF FROPA AS WELL AS AMOUNT OF CLOUDINESS & PRECIP BY MIDDAY WILL BRING A LARGE VARIETY OF CONDITIONS TO THE CWA. WILL KEEP THE BASIC 5 DEGREE RANGE FROM NORTHERN/SOUTHERN CWA AS IS GIVEN THE UNCERTAINTY (84-89F). MUCH MORE PLEASANT WEATHER EXPECTED ON FRIDAY ON INTO THE WEEKEND AS HIGH PRESSURE SETTLES INTO AND THROUGH THE AREA. NO MAJOR CHANGES MADE AS HIGHS FLUTTER AROUND 80 AND LOWS AROUND 60 (65ISH IN THE IMMEDIATE URBAN AREA OF METRO DETROIT). AS THIS HIGH PRESSURE SETTLES ALL THE WAY TO OUR SOUTHEAST AND SOUTH TO SOUTHWEST FLOW RE-ESTABLISHES LATE THIS WEEKEND INTO NEXT WEEK...EXPECT A SLIGHT MODIFICATION BACK INTO THE LOWER/MID 80S FOR HIGHS AND LOWER 60S...ON AVERAGE...FOR LOWS. AGAIN...JUST SMALL ADJUSTMENTS MADE ATTM. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BGM LONG TERM....DG AVIATION.....CONSIDINE mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 716 PM EDT TUE AUG 2 2005 .AVIATION... SURFACE HIGH PRESSURE ANCHORED OVER THE SOUTHERN GREAT LAKES WILL MOVE SOUTH TONIGHT INTO WEDNESDAY. BASED ON CURRENT DEWPOINTS...18Z MODEL SOUNDINGS AND LATEST TAMDAR SOUNDINGS OUT OF DTW... SOUTHWESTERLY RETURN FLOW HAS ALREADY ADVECTED HIGHER LOW LEVEL MOISTURE INTO SE MICHIGAN. TAMDAR SOUNDINGS INDICATE THE MOISTURE PROFILE STEADY TO SLIGHTLY INCREASING THROUGH THE LOWEST 2K FEET. THIS MAY BE ABLE TO ALLOW SOME MVFR VISIBILITIES IN FOG/HAZE TO DEVELOP LATE TONIGHT INTO EARLY WED MORNING... MUCH LIKE WHAT WAS OBSERVED THIS MORNING ACROSS IL AND SW LOWER MI. OTHERWISE... EXPECT VFR CONDITIONS THROUGH THE REST OF THE TAF PERIOD AS THE BEST FOCUS FOR CONVECTION SHOULD REMAIN ACROSS THE NORTHERN GREAT LAKES INTO WED AFTERNOON. && .SHORT TERM...TONIGHT AND WEDNESDAY SURFACE AND UPPER LEVEL RIDGE IS IN PLACE THROUGH MOST OF THIS SHORT TERM FORECAST PERIOD. A SMALL CONVECTIVE CLUSTER WAS PROGRESSING EAST-SOUTHEAST ACROSS CENTRAL MINNESOTA AND CURRENT THICKNESS SCHEMES POINT TOWARD THIS ACTIVITY DIVING SOUTHEAST AWAY FROM THE GREAT LAKES REGION. WHILE WE COULD OBSERVE SOME CI/CS FROM THIS ACTIVITY LATE TONIGHT INTO WEDNESDAY... DO NOT EXPECT ANY ADDITIONAL FEATURES TO PRECLUDE A MOSTLY CLEAR SKY. IN FACT... LATEST H2O VAPOR LOOP SHOWS A WEAK SHORT WAVE CROSSING THE THUMB THIS AFTERNOON WITH PLENTY OF DRY AIR SEEN ACROSS SOUTHERN LAKE MICHIGAN INTO SOUTHERN LOWER MICHIGAN FOR A DRY TONIGHT. AS RIDGE SLOWLY SLIDES TO THE EAST ON WEDNESDAY... INCREASING SOUTHWEST FLOW SHOULD ADVECT NOT ONLY WARMER TEMPERATURES... BUT THE DEWPOINTS AS WELL. TRAJECTORIES ORIGINATE FROM ILLINOIS WHERE SOME MIST (BR) WAS OBSERVED THIS MORNING AND CURRENT TEMPERATURES INTO THE LOWER 90S. MACHINE NUMBERS HAVE RISEN A FEW DEGREES WITH MAINLY MIDDLE 90S AND WE WILL RAISE TEMPERATURES ACCORDINGLY. DEWPOINTS HAVE DROPPED BACKED INTO THE MIDDLE AND UPPER 60S ACROSS THIS REGION AND TRANSPORT INTO THE GREAT LAKES WOULD BRING HEAT INDICES CLOSE TO THE CENTURY MARK...BUT NOT ENOUGH TO WARRANT HEADLINES AT THIS POINT. AS WITH LAKE BREEZE DEVELOPMENT AND COINCIDING WITH CONVECTIVE POTENTIAL... WITH INCREASING SOUTHWEST FLOW IN THE AFTERNOON AND WARMING TEMPERATURES ALOFT... PREFER TO KEEP IT DRY AT THE PRESENT TIME. BUT IF 925-950MB WINDS ARE LESS THAN FORECAST... AS SUGGESTED IN THE RUC13 AND MM5... THEN THE THUMB COULD SEE SOME ADDITIONAL CONVERGENCE AND A SLIGHT CHANCE FOR CONVECTION. GIVEN UPSTREAM CURRENT CONDITIONS WITH A LAKE BREEZE AND NOT MUCH CU... CURRENT THOUGHTS ARE TO REMAIN DRY. && .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY FIRST PROBLEM OF THE FORECAST WILL BE TIMING/EXTENT OF SHOWER AND THUNDERSTORM CHANCES THURSDAY INTO THURSDAY NIGHT. NAM HAS EASED OFF ITS FASTER SOLUTION TODAY...AND HAS THE SAME BASIC IDEA AS GFS. BASICALLY...A SHORTWAVE DRIVING THE FRONT INTO LOWER MICHIGAN BY MIDDAY AND THEN ANOTHER TRAILING SHORTWAVE...WHICH WORKS TO HOLD PRECIPITATION CHANCES INTO THE EVENING HOURS OR THURSDAY. CURRENT FORECAST REALLY HAS THIS SCENARIO PRETTY WELL IN HAND AND PLAN NO MAJOR CHANGES. THE NEXT MAJOR QUESTION IN THE FORECAST COMES TOWARD THE END OF THE FORECAST AS A MORE ZONAL FLOW...OR EVEN BROAD UPPER TROF SETS UP OVER THE NORTHERN TIER OF STATES. ALTHOUGH DETAILS VERY A GREAT DEAL AS WOULD BE EXPECTED THAT FAR OUT...THE GENERAL MODEL PROGS SUPPORT THIS FLOW...WHICH SHOULD PUT THE GREAT LAKES INTO A MORE ACTIVE WEATHER PATTERN (IN RELATION TO THE DOMINATE HIGH PRESSURE EXPECTED OVER THE WEEKEND). PLAN ON ADDING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE MONDAY AND TUESDAY TIMEFRAME BASED ON THIS. AS FOR TEMPERATURES...THURSDAY WILL BE RATHER DIFFICULT TO NAIL DOWN EXACTLY AS TIMING OF FROPA AS WELL AS AMOUNT OF CLOUDINESS & PRECIP BY MIDDAY WILL BRING A LARGE VARIETY OF CONDITIONS TO THE CWA. WILL KEEP THE BASIC 5 DEGREE RANGE FROM NORTHERN/SOUTHERN CWA AS IS GIVEN THE UNCERTAINTY (84-89F). MUCH MORE PLEASANT WEATHER EXPECTED ON FRIDAY ON INTO THE WEEKEND AS HIGH PRESSURE SETTLES INTO AND THROUGH THE AREA. NO MAJOR CHANGES MADE AS HIGHS FLUTTER AROUND 80 AND LOWS AROUND 60 (65ISH IN THE IMMEDIATE URBAN AREA OF METRO DETROIT). AS THIS HIGH PRESSURE SETTLES ALL THE WAY TO OUR SOUTHEAST AND SOUTH TO SOUTHWEST FLOW RE-ESTABLISHES LATE THIS WEEKEND INTO NEXT WEEK...EXPECT A SLIGHT MODIFICATION BACK INTO THE LOWER/MID 80S FOR HIGHS AND LOWER 60S...ON AVERAGE...FOR LOWS. AGAIN...JUST SMALL ADJUSTMENTS MADE ATTM. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BGM LONG TERM....DG AVIATION.....CONSIDINE mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MARQUETTE MI 421 PM EDT TUE AUG 2 2005 .DISCUSSION...THE MAIN CONCERN WITH THIS FORECAST PACKAGE IS POTENTIAL FOR SHOWERS AND THUNDERSTORMS TONIGHT AND WEDNESDAY. WATER VAPOR IMAGERY AND RUC SHOW A RIDGE OVER SOUTH CENTRAL CANADA SEPARATING A LONGWAVE TROUGH OVER THE CANADIAN MARITIME FROM ONE OVER THE CANADIAN ROCKIES. A WEAK SHORTWAVE IS OVER THE MINNESOTA ARROWHEAD. SURFACE ANALYSIS INDICATE LOW PRESSURE CENTERS OVER NORTHWEST MANITOBA AND OVER THE DAKOTAS. A WARM FRONT EXTENDS EAST FROM THE LOW THROUGH CENTRAL ONTARIO...WHILE A COLD FRONT DRAPES SOUTHWEST THROUGH EASTERN MONTANA. THE SHORTWAVE WILL MOVE THROUGH THE U.P. TONIGHT. THE LOW OVER THE DAKOTAS WILL SHIFT INTO NORTHERN MINNESOTA. THE MEAN SURFACE-500MB RH AHEAD OF THE LOW WILL INCREASE TO AROUND 70 PERCENT. FORECAST SOUNDINGS INDICATE A MOIST LAYER BETWEEN 850MB AND 750MB. AN 850MB THETA-E RIDGE WILL STRETCH FROM IRON RIVER TO NORTH OF MANISTIQUE. MODIFYING THE SOUNDINGS TO AFTERNOON TEMPERATURES LOOKS AS IF A FEW SHOWERS AND THUNDERSTORMS WILL FIRE OVER THE AREA...ESPECIALLY OVER THE WEST. LIMITED AVAILABLE MOISTURE WILL KEEP THESE STORMS SCATTERED OR ISOLATED IN THE EVENING HOURS. ANOTHER SHORTWAVE WILL RACE INTO WESTERN U.P. ON WEDNESDAY ALONG WITH THE COLD FRONT. ISENTROPIC ASCENT ALONG WITH THE SHORTWAVE ENERGY WILL SET UP INSTABILITY ACROSS THE AREA. MOISTURE WILL BE LIMITED AGAIN. THUS LOOKING FOR A CHANCE OF SHOWERS IN THE AFTERNOON. MUCAPE OF 4000J/KG WILL SPREAD INTO THE WESTERN U.P. CALLING FOR CHANCE OF SHOWERS AND THUNDERSTORMS AGAIN FOR WEDNESDAY. DUE TO THE EXPECTED INCREASE IN CLOUD COVER TEMPERATURES SHOULD BE A LITTLE LOWER SO WILL BUMP DOWN THE TEMPS CLOSER TO GUIDANCE. A WEAK SHORTWAVE WILL SLIDE ACROSS THE FORECAST AREA WEDNESDAY NIGHT FOLLOWED BY A DEEPER SHORTWAVE ON THURSDAY. THE MEAN SURFACE-500MB WILL AROUND 75 PERCENT. DRY AIR WILL ADVECT IN ON THURSDAY AND END THE CHANCES OF SHOWERS. GFS KEEPS THE CLOSED LOW OVER HUDSON BAY STATIONARY THROUGH TUESDAY...WHEREAS ECMWF MOVES THIS LOW INTO NORTHERN QUEBEC. ON SUNDAY THE MODELS DIVERGE EVEN MORE. THE GFS IS MORE AGGRESSIVE WITH SYSTEM MOVING THROUGH NORTHERN CONUS FASTER THAN THE ECWMF. THE CANADIAN GEM AGREES WITH THE GFS...WHEREAS THE NCEP ENSEMBLES IS A BLEND OF THE TWO. I THINK WILL FAVOR THE BLEND AT THIS TIME RATHER THAN GO WITH ONE OR THE OTHER AS CONFIDENCE IS LOW. AT THE SURFACE THERE SEEMS TO BE BETTER AGREEMENT BUT STILL FAVOR THE BLEND. THE MID LEVEL LOW WILL REMAIN OVER THE HUDSON BAY THURSDAY NIGHT. A SHORTWAVE WILL SWING THROUGH THE FORECAST AREA. THE COLD FRONT WILL MOVE INTO THE LOWER GREAT LAKES AS A SURFACE RIDGE SPREADS ACROSS THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY. SHOWERS SHOULD END OVER THE FORECAST AREA. MID LEVEL STABILITY WILL REMAIN NEUTRAL THROUGH SATURDAY AS THE SURFACE RIDGE SHIFT SLOWLY THROUGH THE FORECAST AREA. MEANWHILE A SURFACE LOW WILL DEVELOP NORTHERN NORTHERN ONTARIO WITH AN ACCOMPANYING COLD FRONT STRETCHING SOUTHWEST THROUGH THE DAKOTAS. A WEAK SHORTWAVE WILL TRACK ACROSS THE NORTHERN PLAINS INTO THE UPPER MISSISSIPPI RIVER VALLEY SATURDAY NIGHT AND SUNDAY AS SURFACE LOW MOVES INTO NORTHERN ONTARIO AND THE COLD FRONT WILL DRAPE INTO NORTHERN MINNESOTA. A SHORTWAVE WILL SHIFT INTO THE FORECAST AREA SUNDAY NIGHT AND PUSHING A COLD FRONT THROUGH THE FORECAST AREA. BOTH MODELS SHOW AN AREA OF MARGINAL MOISTURE ACCOMPANYING THE FRONTAL SYSTEM AS IT SWINGS THROUGH THE AREA. THERE IS A CHANCE OF SHOWERS AND THUNDERSTORMS. BOTH MODELS SHOW STRONGER SHORTWAVE ENERGY AND AN AREA OF INCREASED RH WILL SHIFT ACROSS THE FORECAST MONDAY AND TUESDAY...SO WILL ADD CHANCE OF SHOWERS AND THUNDERSTORMS BOTH DAYS. && .MQT...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ DLG mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 302 PM EDT TUE AUG 2 2005 .SHORT TERM...TONIGHT AND WEDNESDAY SURFACE AND UPPER LEVEL RIDGE IS IN PLACE THROUGH MOST OF THIS SHORT TERM FORECAST PERIOD. A SMALL CONVECTIVE CLUSTER WAS PROGRESSING EAST-SOUTHEAST ACROSS CENTRAL MINNESOTA AND CURRENT THICKNESS SCHEMES POINT TOWARD THIS ACTIVITY DIVING SOUTHEAST AWAY FROM THE GREAT LAKES REGION. WHILE WE COULD OBSERVE SOME CI/CS FROM THIS ACTIVITY LATE TONIGHT INTO WEDNESDAY... DO NOT EXPECT ANY ADDITIONAL FEATURES TO PRECLUDE A MOSTLY CLEAR SKY. IN FACT... LATEST H2O VAPOR LOOP SHOWS A WEAK SHORT WAVE CROSSING THE THUMB THIS AFTERNOON WITH PLENTY OF DRY AIR SEEN ACROSS SOUTHERN LAKE MICHIGAN INTO SOUTHERN LOWER MICHIGAN FOR A DRY TONIGHT. AS RIDGE SLOWLY SLIDES TO THE EAST ON WEDNESDAY... INCREASING SOUTHWEST FLOW SHOULD ADVECT NOT ONLY WARMER TEMPERATURES... BUT THE DEWPOINTS AS WELL. TRAJECTORIES ORIGINATE FROM ILLINOIS WHERE SOME MIST (BR) WAS OBSERVED THIS MORNING AND CURRENT TEMPERATURES INTO THE LOWER 90S. MACHINE NUMBERS HAVE RISEN A FEW DEGREES WITH MAINLY MIDDLE 90S AND WE WILL RAISE TEMPERATURES ACCORDINGLY. DEWPOINTS HAVE DROPPED BACKED INTO THE MIDDLE AND UPPER 60S ACROSS THIS REGION AND TRANSPORT INTO THE GREAT LAKES WOULD BRING HEAT INDICES CLOSE TO THE CENTURY MARK...BUT NOT ENOUGH TO WARRANT HEADLINES AT THIS POINT. AS WITH LAKE BREEZE DEVELOPMENT AND COINCIDING WITH CONVECTIVE POTENTIAL... WITH INCREASING SOUTHWEST FLOW IN THE AFTERNOON AND WARMING TEMPERATURES ALOFT... PREFER TO KEEP IT DRY AT THE PRESENT TIME. BUT IF 925-950MB WINDS ARE LESS THAN FORECAST... AS SUGGESTED IN THE RUC13 AND MM5... THEN THE THUMB COULD SEE SOME ADDITIONAL CONVERGENCE AND A SLIGHT CHANCE FOR CONVECTION. GIVEN UPSTREAM CURRENT CONDITIONS WITH A LAKE BREEZE AND NOT MUCH CU... CURRENT THOUGHTS ARE TO REMAIN DRY. && .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY FIRST PROBLEM OF THE FORECAST WILL BE TIMING/EXTENT OF SHOWER AND THUNDERSTORM CHANCES THURSDAY INTO THURSDAY NIGHT. NAM HAS EASED OFF ITS FASTER SOLUTION TODAY...AND HAS THE SAME BASIC IDEA AS GFS. BASICALLY...A SHORTWAVE DRIVING THE FRONT INTO LOWER MICHIGAN BY MIDDAY AND THEN ANOTHER TRAILING SHORTWAVE...WHICH WORKS TO HOLD PRECIPITATION CHANCES INTO THE EVENING HOURS OR THURSDAY. CURRENT FORECAST REALLY HAS THIS SCENARIO PRETTY WELL IN HAND AND PLAN NO MAJOR CHANGES. THE NEXT MAJOR QUESTION IN THE FORECAST COMES TOWARD THE END OF THE FORECAST AS A MORE ZONAL FLOW...OR EVEN BROAD UPPER TROF SETS UP OVER THE NORTHERN TIER OF STATES. ALTHOUGH DETAILS VERY A GREAT DEAL AS WOULD BE EXPECTED THAT FAR OUT...THE GENERAL MODEL PROGS SUPPORT THIS FLOW...WHICH SHOULD PUT THE GREAT LAKES INTO A MORE ACTIVE WEATHER PATTERN (IN RELATION TO THE DOMINATE HIGH PRESSURE EXPECTED OVER THE WEEKEND). PLAN ON ADDING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE MONDAY AND TUESDAY TIMEFRAME BASED ON THIS. AS FOR TEMPERATURES...THURSDAY WILL BE RATHER DIFFICULT TO NAIL DOWN EXACTLY AS TIMING OF FROPA AS WELL AS AMOUNT OF CLOUDINESS & PRECIP BY MIDDAY WILL BRING A LARGE VARIETY OF CONDITIONS TO THE CWA. WILL KEEP THE BASIC 5 DEGREE RANGE FROM NORTHERN/SOUTHERN CWA AS IS GIVEN THE UNCERTAINTY (84-89F). MUCH MORE PLEASANT WEATHER EXPECTED ON FRIDAY ON INTO THE WEEKEND AS HIGH PRESSURE SETTLES INTO AND THROUGH THE AREA. NO MAJOR CHANGES MADE AS HIGHS FLUTTER AROUND 80 AND LOWS AROUND 60 (65ISH IN THE IMMEDIATE URBAN AREA OF METRO DETROIT). AS THIS HIGH PRESSURE SETTLES ALL THE WAY TO OUR SOUTHEAST AND SOUTH TO SOUTHWEST FLOW RE-ESTABLISHES LATE THIS WEEKEND INTO NEXT WEEK...EXPECT A SLIGHT MODIFICATION BACK INTO THE LOWER/MID 80S FOR HIGHS AND LOWER 60S...ON AVERAGE...FOR LOWS. AGAIN...JUST SMALL ADJUSTMENTS MADE ATTM. && .PREV DISCUSSION... (ISSUED 115 PM EDT TUE AUG 2 2005) AVIATION... WE REMAIN UNDER THE RIDGE THROUGH THE EVENING HOURS...AS IT SLOWLY MIGRATES TO THE EAST WEDNESDAY MORNING. THIS WILL KEEP VFR CONDITIONS THROUGH 18Z WEDNESDAY WITH SOME CI/CS SPILL-OVER FROM UPSTREAM CONVECTION. MONITORING TRAJECTORIES... FROM CENTRAL ILLINOIS... WE COULD SEE SOME MIST (BR) LATE TONIGHT WITH SFC DEWPOINT DEPRESSIONS DROPPING TO 1-2C. OTHERWISE... A TRANQUIL TAF PERIOD FOR THE GREAT LAKES. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BGM LONG TERM....DG AVIATION.....BGM mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE COLUMBIA SC 1017 AM EDT TUE AUG 2 2005 .SHORT TERM (REST OF TONIGHT)... DRIER AMS CONTS TO FILTER INTO AREA WITH FNTL BNDRY WELL OFFSHORE. HV LOWER SKY COVER AND RAISED TEMPS FOR AFTN UPDATE. NO OTHR CHNGS ATTM. && .PREVIOUS DISCUSSION... (ISSUED 338 AM EDT TUE AUG 2 2005) SHORT TERM (TODAY THROUGH THURSDAY)... SATELLITE SHOWS MAINLY HIGH CLOUDS MOVING ACROSS THE AREA THIS MORNING. 88D SHOWS ONLY PCPN TO BE FOUND ALONG/OFF THE COASTAL AREAS FROM NC TO GA. BOTH NAM/GFS CONTINUE WITH PREVIOUS RUNS OF DRYING ATMOSPHERE OUT ACROSS THE AREA TODAY THROUGH WEDNESDAY. RIDGE OF HIGH PRESSURE CONTINUE TO BE ANCHORED WELL TO OUR WEST ACROSS ROCKIES/CNTRL PLAINS. SOUTHEAST STILL UNDER A BIT OF A WEAKNESS THAT EXTENDS OFF THE COAST. AT THE SURFACE...PERSISTENT OLD BOUNDARY LINGERING JUST OFF THE COAST. BOTH NAM/GFS INDICATE SHORTWAVE TO APPROACH THE AREA THIS AFTERNOON/EVENING. AT THE SURFACE...BOTH MODELS TRY TO PUSH WEAK AREA OF HIGH PRESSURE SEWD INTO THE AREA. MODEL TIME SECTIONS SHOW THERE IS STILL SOME LOW LEVEL MOISTURE AVAILABLE..ESPECIALLY ACROSS THE SRN PORTION OF THE CWA. WITH DAYTIME HEATING AND ATMOSPHERE BECOMING MODERATELY UNSTABLE...MAINLY DUE TO COOL POOL ASSOCIATED WITH SHORTWAVE...WILL MENTION SLIGHT CHANCE OF SHRA/TSRA ACROSS THE CENTRAL PORTION OF THE CWA WITH CHANCE POPS TO THE SOUTH. QUITE A BIT OF DIFFERENCE IN THE STABILITY INDICES BETWEEN THE GFS AND NAM...MAINLY DUE TO WARMER TEMPERATURES ALOFT THAN NAM. MORNING RUC SOMEWHERE IN BETWEEN THE TWO. BY WEDNESDAY...BOTH NAM/GFS PUSH SHORTWAVE AND THEREFORE MOISTURE A BIT FARTHER SOUTH. WILL KEEP FORECAST DRY FOR NORTHERN HALF OF THE CWA AND ONLY MENTION A SLIGHT CHANCE SHRA/TSRA SOUTH. BY THU...WEAK SURFACE HIGH PRESSURE CONTINUES ACROSS THE AREA. GUIDANCE AND LOCAL EQUATIONS FOR POPS AND TEMPERATURES VERY SIMILAR AND WILL STAY CLOSE TO/JUST BLO CONSENSUS VALUES THROUGH THE PERIOD. LONG TERM (THURSDAY NIGHT THROUGH MONDAY)... RIDGING ACROSS THE WRN PORTION OF THE COUNTRY TENDS TO WEAKEN AS FLOW BECOMES MORE ZONAL ACROSS THE AREA OVER THE WEEKEND. SURFACE FRONT TO OUR WEST CONTINUES EWD ACROSS NEW ENGLAND...BUT NEVER REALLY MAKES IT AS FAR SOUTH AS THE CAROLINAS. BY THE WEEKEND...AREA BECOMES MORE INFLUENCED BY WEAK BERMUDA TYPE HIGH PRESSURE OFF THE COAST PRODUCING MORE TYPICAL EARLY AUGUST CONDITIONS. EXPECT TEMPERATURES/PCPN TO BE CLOSE TO SEASONAL VALUES. AVIATION... MVFR VSBYS EXPECTED THRU 13Z OTHERWISE VFR VSBYS/CEILINGS THRU 03/06Z THEN VSBYS BECOMING MVFR. DO NOT THINK STRATUS WILL BE A PROBLEM THIS MORNING...BUT DID PUT SCT STRATUS LAYER THIS MRNG. MAY SEE A FEW BANDS OF SCT CU 4-6 THSD FT NEXT FEW HOURS IN EASTERLY FLOW BUT NOT ENOUGH FOR TAFS. WIDELY SCATTERED/SCATTERED TSRA EXPECTED DURING THE LATE AFTERNOON/EVENING CAE SOUTHWARD. TSRA SHOULD BE MORE NUMEROUS SOUTH AND EAST OF CAE. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ sc AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE HANFORD CA 930 PM PDT TUE AUG 2 2005 .SHORT TERM...FOR THE CENTRAL CALIFORNIA INTERIOR...CLEAR SKIES CONTINUE OVER THE DISTRICT THIS EVENING AS A STABLE AIRMASS REMAINS OVER THE REGION. CURRENTLY AS OF 900 PM...RUC ANALYSIS HAD THE AXIS OF A TROF PUSHING THROUGH CALIFORNIA NEAR THE NEVADA BORDER. THIS TROF PASSAGE INTRODUCED A MORE WESTERLY FLOW ALOFT AND PUSHED THE MONSOONAL MOISTURE MORE INTO THE ROCKY MOUNTAINS. THEREFORE... THUNDERSTORM THREAT OVER THE SIERRA NEVADA WAS ELIMINATED WITH THE DRY/CLEAR WEATHER EXPECTED AGAIN ON WEDNESDAY. MODELS LIFT THE TROF INTO THE NORTHERN PLAINS BY LATER WEDNESDAY...ALLOWING THE RIDGE TO START REBUILDING OVER THE WEST COAST. AS THE FOUR CORNERS HIGH REBOUNDS...A MORE SOUTHEASTERLY FLOW PATTERN WILL ONCE AGAIN REDEVELOP. THEREFORE...WHILE WEDNESDAY WILL BE ANOTHER CLEAR DAY...THE THREAT OF THUNDERSTORMS WILL RETURN TO THE CWFA STARTING ON THURSDAY. WILL MAINTAIN SLIGHT CHANCE WORDING FOR THURSDAY AFTERNOON. ALL FORECAST GRIDS ON TRACK WITH CURRENT THINKING...SO NO UPDATES NEEDED THIS EVENING. && .AVIATION...VFR CONDITIONS WILL PREVAIL ACROSS ALL AREAS THROUGH AT LEAST 06Z THURSDAY. REFER TO TAFS AT KMCE...KFAT...AND KBFL FOR DETAILS. && .HNX...WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WWW.WEATHER.GOV/HANFORD /USE ALL LOWER CASE/ MOLINA ca AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI 103 AM EDT WED AUG 3 2005 .AVIATION... GETTING SEVERAL MVFR VISIBILITY OBSERVATIONS ACROSS SOUTHERN MICHIGAN WITH DEWPOINTS IN THE UPPER 60S TO NEAR 70. WITH LIGHT WINDS AND MAINLY CLEAR SKIES THESE VISIBILITIES SHOULD PERSIST THROUGH DAYBREAK. MAY SEE SOME PERIODS OF IFR VISIBILITY NEAR MBS AND FNT TOWARD SUNRISE. WITH THE ONSET OF DIURNAL HEATING... SHOULD SEE VISIBILITIES IMPROVE BY LATE MORNING/EARLY AFTERNOON. THERE WILL BE QUITE A BIT OF INSTABILITY WED AFTERNOON. MODEL SOUNDINGS ARE SHOWING LIFTING INDICES AROUND -6C. NOT MUCH IN THE WAY OF SURFACE CONVERGENCE OR LARGE SCALE LIFT EXPECTED. SO WILL KEEP THUNDERSTORMS OUT OF THE TAFS THROUGH THE AFTERNOON AND INTO THE EVENING AT THIS TIME. MORE ORGANIZED LIFT WILL ARRIVE AFTER THE FORECAST PERIOD IN THE FORM OF A MID LEVEL SHORT WAVE AND SURFACE COLD FRONT. && .UPDATE.... ISSUED AT 1012 PM. A STRONG SUBTROPICAL RIDGE OVER THE CENTRAL US AND HIGH PRESSURE CENTERED JUST SOUTH OF THE AREA WILL KEEP SE MICHIGAN PRECIP FREE TONIGHT. SHOULD JUST SEE SOME CIRRUS ADVANCING INTO THE REGION FROM THE NORTH FROM TIME TO TIME. BASED ON THE LATEST TRENDS... CURRENT TEMP FORECAST LOOKS ON TARGET. IT WILL BE A RATHER MUGGY NIGHT WITH DEWPOINTS RANGING FROM THE MID 60S TO LOWER 70S. THIS LOW LEVEL MOISTURE WILL RESULT IN SOME FOG. DO NOT THINK WE WILL RADIATE TOO MUCH WITH SOME LIGHT SW WINDS... SO NOT EXPECTING VISIBILITY TO DROP BELOW 2 MILES. THUS THE GOING FORECAST LOOKS ON TARGET SO NO UPDATES WILL BE MADE. && .SHORT TERM...TONIGHT AND WEDNESDAY SURFACE AND UPPER LEVEL RIDGE IS IN PLACE THROUGH MOST OF THIS SHORT TERM FORECAST PERIOD. A SMALL CONVECTIVE CLUSTER WAS PROGRESSING EAST-SOUTHEAST ACROSS CENTRAL MINNESOTA AND CURRENT THICKNESS SCHEMES POINT TOWARD THIS ACTIVITY DIVING SOUTHEAST AWAY FROM THE GREAT LAKES REGION. WHILE WE COULD OBSERVE SOME CI/CS FROM THIS ACTIVITY LATE TONIGHT INTO WEDNESDAY... DO NOT EXPECT ANY ADDITIONAL FEATURES TO PRECLUDE A MOSTLY CLEAR SKY. IN FACT... LATEST H2O VAPOR LOOP SHOWS A WEAK SHORT WAVE CROSSING THE THUMB THIS AFTERNOON WITH PLENTY OF DRY AIR SEEN ACROSS SOUTHERN LAKE MICHIGAN INTO SOUTHERN LOWER MICHIGAN FOR A DRY TONIGHT. AS RIDGE SLOWLY SLIDES TO THE EAST ON WEDNESDAY... INCREASING SOUTHWEST FLOW SHOULD ADVECT NOT ONLY WARMER TEMPERATURES... BUT THE DEWPOINTS AS WELL. TRAJECTORIES ORIGINATE FROM ILLINOIS WHERE SOME MIST (BR) WAS OBSERVED THIS MORNING AND CURRENT TEMPERATURES INTO THE LOWER 90S. MACHINE NUMBERS HAVE RISEN A FEW DEGREES WITH MAINLY MIDDLE 90S AND WE WILL RAISE TEMPERATURES ACCORDINGLY. DEWPOINTS HAVE DROPPED BACKED INTO THE MIDDLE AND UPPER 60S ACROSS THIS REGION AND TRANSPORT INTO THE GREAT LAKES WOULD BRING HEAT INDICES CLOSE TO THE CENTURY MARK...BUT NOT ENOUGH TO WARRANT HEADLINES AT THIS POINT. AS WITH LAKE BREEZE DEVELOPMENT AND COINCIDING WITH CONVECTIVE POTENTIAL... WITH INCREASING SOUTHWEST FLOW IN THE AFTERNOON AND WARMING TEMPERATURES ALOFT... PREFER TO KEEP IT DRY AT THE PRESENT TIME. BUT IF 925-950MB WINDS ARE LESS THAN FORECAST... AS SUGGESTED IN THE RUC13 AND MM5... THEN THE THUMB COULD SEE SOME ADDITIONAL CONVERGENCE AND A SLIGHT CHANCE FOR CONVECTION. GIVEN UPSTREAM CURRENT CONDITIONS WITH A LAKE BREEZE AND NOT MUCH CU... CURRENT THOUGHTS ARE TO REMAIN DRY. && .LONG TERM...WEDNESDAY NIGHT THROUGH TUESDAY FIRST PROBLEM OF THE FORECAST WILL BE TIMING/EXTENT OF SHOWER AND THUNDERSTORM CHANCES THURSDAY INTO THURSDAY NIGHT. NAM HAS EASED OFF ITS FASTER SOLUTION TODAY...AND HAS THE SAME BASIC IDEA AS GFS. BASICALLY...A SHORTWAVE DRIVING THE FRONT INTO LOWER MICHIGAN BY MIDDAY AND THEN ANOTHER TRAILING SHORTWAVE...WHICH WORKS TO HOLD PRECIPITATION CHANCES INTO THE EVENING HOURS OR THURSDAY. CURRENT FORECAST REALLY HAS THIS SCENARIO PRETTY WELL IN HAND AND PLAN NO MAJOR CHANGES. THE NEXT MAJOR QUESTION IN THE FORECAST COMES TOWARD THE END OF THE FORECAST AS A MORE ZONAL FLOW...OR EVEN BROAD UPPER TROF SETS UP OVER THE NORTHERN TIER OF STATES. ALTHOUGH DETAILS VERY A GREAT DEAL AS WOULD BE EXPECTED THAT FAR OUT...THE GENERAL MODEL PROGS SUPPORT THIS FLOW...WHICH SHOULD PUT THE GREAT LAKES INTO A MORE ACTIVE WEATHER PATTERN (IN RELATION TO THE DOMINATE HIGH PRESSURE EXPECTED OVER THE WEEKEND). PLAN ON ADDING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE MONDAY AND TUESDAY TIMEFRAME BASED ON THIS. AS FOR TEMPERATURES...THURSDAY WILL BE RATHER DIFFICULT TO NAIL DOWN EXACTLY AS TIMING OF FROPA AS WELL AS AMOUNT OF CLOUDINESS & PRECIP BY MIDDAY WILL BRING A LARGE VARIETY OF CONDITIONS TO THE CWA. WILL KEEP THE BASIC 5 DEGREE RANGE FROM NORTHERN/SOUTHERN CWA AS IS GIVEN THE UNCERTAINTY (84-89F). MUCH MORE PLEASANT WEATHER EXPECTED ON FRIDAY ON INTO THE WEEKEND AS HIGH PRESSURE SETTLES INTO AND THROUGH THE AREA. NO MAJOR CHANGES MADE AS HIGHS FLUTTER AROUND 80 AND LOWS AROUND 60 (65ISH IN THE IMMEDIATE URBAN AREA OF METRO DETROIT). AS THIS HIGH PRESSURE SETTLES ALL THE WAY TO OUR SOUTHEAST AND SOUTH TO SOUTHWEST FLOW RE-ESTABLISHES LATE THIS WEEKEND INTO NEXT WEEK...EXPECT A SLIGHT MODIFICATION BACK INTO THE LOWER/MID 80S FOR HIGHS AND LOWER 60S...ON AVERAGE...FOR LOWS. AGAIN...JUST SMALL ADJUSTMENTS MADE ATTM. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ SHORT TERM...BGM LONG TERM....DG AVIATION.....CONSIDINE mi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSON MS 340 AM CDT WED AUG 3 2005 .DISCUSSION... A WEAK UPPER SHEAR AXIS AND A MOIST ATMOSPHERE WILL REMAIN THE KEY FEATURES FOR OUR SENSIBLE WX AGAIN TODAY. FOR THE MOST PART...THE FORECAST FOR THE FIRST 24 HRS WAS BASED ON PERSISTENCE...WITH A FEW DIFFERENCES IN MY NORTHERN TIER OF ZONES. TODAY...TWO WEAK UPPER SHEAR AXES ARE NOTED THIS MORNING VIA WATER VAPOR IMAGERY AND 500MB RUC INITIALIZATIONS. ONE IS HUGGING THE GULF COAST...WHILE THE OTHER IS HOVERING ROUGHLY OVER CENTRAL MS. WATER VAPOR IMAGERY INDICATING MID LEVEL DRYING WORKING ITS WAY THROUGH NE MS... WITH HIGHEST PWAT AIR OVER CENTRAL/SOUTHERN PORTIONS OF THE STATE. SHORT RANGE GUIDANCE TRACKS THIS DRYING (ALSO NOTED AT 850MB) SOUTHWESTWARD INTO MY NORTHERN ZONES THIS MORNING AND THE DELTA AREA BY THIS AFTERNOON...WITH DEEP MOISTURE HOLDING ON ALONG AND SOUTH OF THE I-20 CORRIDOR. 925/850MB TEMPS VIRTUALLY THE SAME AS WHAT WAS OBSERVED YESTERDAY...THUS HIGHS SHOULD AGAIN REACH THE 89-93F RANGE. WITH LOW 70S DEWPOINTS...SBCAPES SHOULD PEAK AROUND 3000 J/KG IN THE PRESENCE OF -5C LIS. ALL TOLD...LOWER SHRA/TSRA COVERAGE IS ANTICIPATED TODAY IN AREAS NORTH OF THE I-20 CORRIDOR. LOW LEVEL THETA-E MINIMA AND DRYING AT MID LEVELS HAS LED ME TO INCLUDE ONLY SLGT CHANCE/LOW END CHANCE POPS IN THIS AREA. AREAS ROUGHLY ALONG THE I-20 CORRIDOR WILL BE BETWEEN DRYING CONDITIONS FROM THE NORTH AND DEEP MOISTURE JUST TO THE SOUTH. MAV NUMBERS AT SITES SUCH AS TVR AND JAN SEEMED JUST A TOUCH LOW AND INCREASED THEM TO SOLID CHC CATEGORY. IN MY SOUTHERN ZONES...WEAK LOW LEVEL THETA-E RIDGING AND HIGH PWAT AIR MAKE IT HARD TO ARGUE WITH GOING LIKELY POPS. AS HAS BEEN THE CASE THE PAST FEW DAYS...THE BULK OF THE ACTIVITY WILL OCCUR FROM LATE MORNING TO LATE AFTERNOON. TONIGHT...CARBON COPY OF THE PAST FEW NIGHTS. SHRA/TSRA ACTIVITY SHOULD QUICKLY SHUT DOWN AFTER 7PM WITH FAIR CONDITIONS THEREAFTER. LOW TEMPS WILL AGAIN BOTTOM OUT RIGHT AROUND AVERAGE FOR THIS TIME OF YEAR./25/ HEADING INTO THE MEDIUM RANGE...WE ARE STAYING CLOSER TO THE ECMWF CONSISTENT SOLUTION OF W TO E MID-UPPER LEVEL RIDGING BUILDING INTO THE TN VALLEY REGION LEAVING A WEAK SHEAR AXIS ACROSS SRN MS AND ALONG THE GULF COAST. ACTUALLY THE NAM APPEARS TO BE A DECENT COMPROMISE BETWEEN THE ECMWF AND GFS AS IT INDICATES A CLOSED LOW DRIFTING WWD ALONG THE LA COAST THIS WEEKEND. LATEST 2 RUNS OF GFS LOOK TO GET CARRIED AWAY WITH A CUTOFF UPPER LOW MOVING UP THE MS RIVER SUNDAY/MONDAY. THE 500MB HEIGHTS AT LEAST 50M LOWER THAN RUNS FROM YESTERDAY! AT ANY RATE...WILL MAINTAIN NEAR CLIMATOLOGY POPS/TEMPS OVER SRN MS/NE LA FRIDAY THROUGH TUESDAY WITH A LITTLE DRIER/WARMER SCENARIO FOR NRN MS ACROSS SERN AR. HAVE BOOSTED OVERNIGHT CLOUD COVERS MAINLY S OF I-20 STARTING SUNDAY ALONG WITH ADDING SMALL EVENING/MORNING POPS FOR SHRA. PWATS SHOULD REMAIN NEAR 1.7-1.9" EARLY NEXT WEEK WITH K INDEXES 30-35 AND MID LEVEL LAPSE RATES 5-5.5C/KM. REST OF THE FORECAST NEXT WEEK APPEARS TO BE ONE OF CLIMATOLOGY FOR NOW AS THE TROPICS BEGIN TO START STIRRING ONCE AGAIN. && .AVIATION... 12Z TAF PACKAGE WILL CONTINUE TREND FROM 06Z PACKAGE. FIRST ISSUE WILL BE CLEARING OUT STRATUS/LOCALIZED FOG AT KHBG AND KMEI. AFTER REFERENCING OBS AT THESE SITES FOR THE PAST FEW MORNINGS...HAVE OPTED TO USE PERSISTENCE (14-15Z) FOR TIMING THE LIFTING/BURNING OFF OF STRATUS/FOG. NEXT ISSUE WILL AGAIN BE SHRA/TSRA ACTIVITY FOR THE AFTERNOON HOURS. WILL CONTINUE WITH VCTS AT JAN/MEI/HBG DURING THE AFTERNOON...WITH A TEMPO COVERING TSRA AT KHBG. WILL ONLY MENTION CB AT KGLH AND KGWO AS DRYING AT LOW/MID LEVELS WILL MAKE ANY SHRA/TSRA A LITTLE MORE SPARSE IN COVERAGE VERSUS THE PAST FEW DAYS. LOOKING AHEAD TOWARD FOG/STRATUS POTENTIAL FOR TONIGHT...KHBG WILL REMAIN PRONE TO FOG AND STRATUS WHILE POTENTIAL AT GLH/GWO/JAN/MEI A LITTLE MORE MURKY. MVFR VIS WILL LIKELY BE ON TAP...BUT CONFIDENCE IN IFR/LIFR CIGS LOW./25/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 91 72 91 72 / 40 10 30 20 MERIDIAN 91 71 91 71 / 40 20 20 20 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 25/40 ms AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 416 AM EDT WED AUG 3 2005 .SHORT TERM (TODAY THROUGH FRIDAY NIGHT)...QUIET ERLY MRNG ASIDE FROM SOME PATCHY FOG...TEMPS MAINLY IN 70S. DEW PTS (MAINLY 70 TO 75) ARE A LITTLE HIGHER THAN YSDY AT THIS TIME. WK SFC HIGH PRES WILL REMAIN IN CONTROL TODAY...BUT EXPECT A THERALLY INDUCED LEE TROF TO DEVELOP BY AFTN. THIS FEATURE WILL BE WEAK...BUT W/ DEW PTS JUST A BIT HIGHER...RUC SNDGS SHOWING K-INDICES APPRCHNG UPR 30/NEAR 40...AND TEMPS CLIMBING INTO MID 90S COULD SEE A STRAY SHOWER/TSTM DEVELOP BY LATE AFTN. HAVE A SLGT CHC FOR SRN PIEDMNT/INLAND NC IN ZONE OF BEST LOW LVL CONV. OTHERWISE...STILL LOOKS A BIT TOO CAPPED/AND DRY ABOVE 700 MB FOR ANY ORGANIZED PRECIP. THU/FRI...NEXT SHORTWAVE DIVES SEWD FROM HUDSON BAY UPR LOW INTO UPR MIDWEST...AMPLIFYING RIDGING ACRS SCNRTL/SE CONUS. TEMPS THU WILL WARM INTO MID/UPR 90S FOR INLAND VA/NC (A LITTLE COOLER ON COAST). STAYED A BIT BLO MAV GDNC WHICH HAS NEAR 100 IN WRN ZONES THU AS DOWNSLOPING WILL BE LMTD AND H8 TEMPS TOP OUT ABOUT 19C. BY FRIDAY...FRONTAL BNDRY/UPR SHORTWV DRIFTS CLOSER TO REGION...BUT STRONGER SW FLOW WILL HELP TRANSPORT MID 90S TO COASTAL AREAS LIKE ORF. DEEPER MSTR LOOKS LMTD AS WLY DOWNSLOPING DEVELOPS IN 900 TO 700 MB LYR. WILL CARRY CHC POPS IN NRN PIEDMNT...TAPERED TO SCHC ELSEWHERE BY LATE AFTN. A BIT MORE LOW LVL CONV/UPR SUPPORT MOVES OVERHEAD DURING EVENG SO HAVE LOW CHC POPS ALL ZONES BY THEN. && .LONG TERM (SATURDAY THROUGH TUESDAY)...COOLED TEMPS A BIT ON SATURDAY...HIGHS MAINLY IN MID/UPR 80S W/ SOMEWHAT MORE CLOUD CVR AS FRONTAL BNDRY STALLS ACRS VA. ALOT OF UNCERTAINTY AS TO EXACT LOCATION OF BNDRY SO WILL KEEP CHC POPS GOING SAT INTO LATE MON NGT IN VCNTY OF FRONT. && .AVIATION... WEAK BNDRY LAYER MIXING HAS PREVENTED FOG FROM BCMG TOO WIDESPREAD/DENSE EARLY THIS MORN. SOME THICKER PATCHES AROUND BEFORE SUNRISE...BUT MOST TAF SITES WL MAINTAIN AT LEAST MVFR VSBYS (EXCEPT TEMPO IFR/LIFR AT SBY) WITH IMPROVING CONDS TO VFR ALL AREAS AN HOUR OR 2 AFTER SUNRISE. && .MARINE... BENIGN BOATING CONDS EXPECTED NEXT FEW DAYS. LIGHT SW WINDS SHIFT N AS WEAK SFC TROF DROPS THRU MARINE AREA THIS MORN. LIGHT ONSHORE FLOW DEVELOPS THIS AFTN AS PRES GRADIENT BECOMES DIFFUSE. WINDS BCMG MORE S/SW OVR MARINE AREA ON THU DUE WEAK LEESIDE TROF DEVELOPMENT BUT SPEEDS GREATER THAN 10 KTS IN THE BAY/SOUND AND 15 KTS ALONG CSTL WTRS HARD TO COME BY. SW WINDS PICK UP SOME ON FRI AHEAD APPROACHING COLD FRONT. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SHORT TERM/LONG TERM...BROWN AVIATION/MARINE...CULLEN va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MILWAUKEE/SULLIVAN WI 327 AM CDT WED AUG 3 2005 .DISCUSSION...FORECAST FOCUS CENTERED ON CHANCES OF RAIN TODAY THROUGH THURSDAY. UPPER TROUGH AXIS ALONG BORDER OF SASK. AND ALBERTA IS PROGGED TO PUSH EAST WITH SRN PORTION TO PROGRESS ACROSS SRN WI THU EVENING. UNTIL THEN...WAA PATTERN IN LOWER TO MID TROPOSPHERE WILL CONTINUE TODAY. LATEST RUC SOUNDINGS PICK UP MID LEVEL CLOUDS AND WEAK ELEVATED INSTABILITY AROUND 600 MB. THUS WILL KEEP A SMALL POP IN TODAY. 850 MB TO 700 MB THERMAL RIDGE ARRIVES BY 00Z THEREBY MARKING THE END OF WAA PATTERN. FOR CDFNT WILL CONTINUE TO USE GFS WITH FROPA THU AM. LOW LEVEL FRONTOGENESIS IS WEAKER AND NOT AS WELL ORGANIZED THAN PREVIOUS 00Z RUN. ONLY A WEAK VORTICITY MAXIMUM TO AID IN LIFT AFT 06Z AND INTO DAYLIGHT HOURS ON THU. RH REMAINS FAIRLY LOW FROM 800 MB AND BELOW EVEN WHILE MODELS ARE GENERATING QPF. DECIDED TO BACK OF ON POPS TNT WITH NO LIKELY POPS FOR THIS EVENT. SCT CLOUD COVER TODAY WILL OFFSET ADDITIONAL WAA TO KEEP TEMPS IN THE LOWER 90S SIMILAR TO YESTERDAY. THU HIGH TEMPS WILL DEPEND ON DEGREE OF CLOUD COVER AND PCPN WITH FROPA. BASICALLY KEPT TEMPS THE SAME AS PREVIOUS FCST FOR MOST PERIODS. .MKX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ GEHRING wi AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 1000 AM EDT WED AUG 3 2005 .UPDATE...MID LEVEL SHEAR AXIS ACROSS THE REGION IS AFFECTING THE STEERING FLOW AND EXPLAINS WHY THE CONVECTION NEAR THE GA COAST STOPS MOVING SWD AROUND BRUNSWICK. PWATS ARE AOA 2 INCHES ACROSS NORTH FL AND SRN GA THEN DROP OFF DRAMATICALLY NORTH OF OUR CWA AS EVIDENCED BY 2.11 INCHES/1.27 INCHES IN THE JAX/CHS SOUNDINGS RESPECTIVELY. INSTABILITY IS HIGH AND HEAVY RAIN IS ONCE AGAIN EXPECTED WHERE PWATS ARE HIGH. CLOUD COVER IS THICK AGAIN TODAY OVER SE GA WITH PATCHES OF LIGHT RAIN. THE RUC SHOWS CONVECTION STARTING EARLY IN THE FL ZONES THEN SPREADING EVERYWHERE BY LATE AFTN. WILL PROBABLY TWEAK TEMPS AND WIND GRIDS BUT ONLY MINOR CHANGES EXPECTED. && .MARINE...SLIGHT SURGE...WINDS UP TO 12-14 KT...IS OCCURRING ALONG THE GA COAST WHERE PRES GRAD IS SANDWICHED BETWEEN A LOW OFFSHORE AND A HIGH TO THE NORTH. ELSEWHERE WINDS ARE LESS THAN 10 KT. && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. MARINE...NONE. && $$ MKT/JTD fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MELBOURNE FL 945 AM EDT WED AUG 3 2005 .DISCUSSION... TODAY...DEEP LAYER RIDGE CONTINUES ACROSS THE SOUTHERN HALF OF THE PENINSULA. MORNING SOUNDINGS AND CANAVERAL PROFILER SHOWING SURFACE TO MID LEVEL WESTERLY FLOW AT GENERALLY 10 KNOTS OR LESS. NOTICED SLIGHTLY LOWER PRECIPITABLE WATER AT TAMPA AND KEY WEST. WATER VAPOR LOOP SHOWS SOME DRY AIR ROTATING ANTICYCLONICALLY AROUND THE MID/UPPER ANTICYCLONE OVER SOUTH FLORIDA. DRIER AIR DOES NOT SEEM TO BE HAVING MUCH OF A SUPPRESSING INFLUENCE ON GULF CONVECTION THOUGH. RUC SOUNDINGS INDICATE RATHER TYPICAL SUMMERTIME CAPE VALUES OF 2000-2500 J/KG. WILL CONTINUE WITH LIKELY POPS IN THE NORTH... WHICH IS CLOSER TO THE WEAK LOW LEVEL TROUGH...AND 50 PERCENT ELSEWHERE. WOULD NOT BE SURPRISED TO SEE LIKELY COVERAGE OVER A GREATER AREA AS SOME MID LEVEL CASTELLANOS WERE SPOTTED OUT THE WINDOW...WHICH USUALLY PORTENDS AN ACTIVE AFTERNOON. BUT WITH SOME DEBRIS CLOUDS...500 MB TEMPS ONLY AT ABOUT MINUS 5-6 DEGREES AND POSSIBLY A LITTLE DRYING ALOFT...WILL MAINTAIN CURRENT FORECAST. && .MARINE...LIGHT SW WINDS 5-10 KNOTS THIS MORNING WILL BECOME NE NEAR THE COAST THIS AFTERNOON WITH THE AFTN SEA BREEZE. MAIN CONCERN TODAY IS LATE AFTN STORMS DRIFTING EAST TWD THE INTRACOASTAL AND NEARSHORE WATERS. OTRW...NOT MUCH TO TALK ABOUT AS WINDS REMAIN BELOW 10KT OUTSIDE OF THE SEA BREEZE CIRC...WITH SEAS AOB 3FT. && .AVIATION...LOOKS LIKE AFTERNOON STORMS AND OUTFLOWS WORKING OVER THE ATMOSPHERE WITH MOST ACTIVITY DONE BY 00Z OR 01Z. && .MLB WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...LASCODY LONG TERM....HIRSCH fl AREA FORECAST DISCUSSION...UPDATE NATIONAL WEATHER SERVICE DES MOINES IA 950 AM CDT WED AUG 3 2005 .DISCUSSION... FORECAST UPDATE ON THE WAY FOR MORNING CONVECTIVE TRENDS. WILL EXTEND SOME ISOLATED WORDING TO ZOE FORECAST FOR SE SECTIONS OF CENTRAL IOWA LATE THIS AM. ISENTROPIC LIFT DIMINISHING OVER THE AREA AND LIGHTNING NETWORK SHOWING CONVECTION HAS BECOME PRIMARILY REMOVED TO EXTREME EASTERN IA. RUC INDICATING REDEVELOPING ISENT FORCING ON THE 315K SFC AGAIN THIS AFTERNOON OVER DSM...HOWEVER WITH 700 MB TEMPS ON THE INCREASE A CAP SHOULD BE IN PLACE AND RUC NOT INDICATING ANY CONVECTIVE PCPN. PLANNING NO ADJUSTMENTS ON TEMPS AS WINDS LOOK TO BE MIXING OUT WELL AT THIS POINTS AND TEMPS OVER MUCH OF THE AREA HAVE REACHED 80 DEG OR BETTER. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ RUSSELL ia AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GOODLAND KS 944 AM MDT WED AUG 3 2005 .DISCUSSION... PRIMARY CONCERN IN THE SHORT TERM WILL BE WX TIMING AND MAX TEMPS. KGLD 88D IMAGERY INDICATING WEAK BOUNDARY SLIDING ACROSS THE CWA ATTM. THIS SUBTLE CONVERGENCE BOUNDARY SHOULD BEGIN TO LIFT NORTH IN THE NEXT COUPLE OF HOURS AS CYCLOGENESIS GETS GOING AHEAD OF SHORT WAVE ACROSS WYOMING. LOOKS LIKE A SIMILAR SET UP TO YESTERDAY WITH A PERSISTENT AREA OF WEAK CONVERGENCE RIGHT AROUND TIME OF MAX HEATING...SO SPED UP POPS A BIT TO ACCOUNT FOR A FEW ISOLATED AFTERNOON STORMS BEFORE MAIN COLD FRONT GETS HERE. MAX TEMPS LOOK ON TRACK AND MADE NO LARGE CHANGES. ETA STILL NOT MIXING OUT SFC DEWPOINT MUCH AT ALL TODAY AND AM GOING MORE OF RUC MAV COMPROMISE NUMBERS WHICH ARE DRIER...BUT SHOULD NOT CAUSE ANY NEED FOR FIRE WX HIGHLIGHT. && .PREV DISCUSSION...MAIN FEATURE TO MONITOR THE NEXT 36 HOURS IS THE COLD FRONT THAT CURRENTLY EXTENDS ALONG THE NEBRASKA/SOUTH DAKOTA BORDER. FRONT WILL CONTINUE TO MOVE SOUTH TODAY...AND WILL REACH THE NORTHERN FORECAST AREA THIS AFTERNOON. THE CHALLENGES WITH THIS FORECAST WILL BE THE AMOUNT OF CONVECTION WITH THE FRONT...CHANCES OF POST FRONTAL PRECIPITATION WITH UPSLOPE FLOW...AND TEMPERATURES AHEAD OF THE FRONT TODAY AND BEHIND THE FRONT THURSDAY. HEAVE LEANED TOWARDS THE GFS SOLUTION WITH THIS PACKAGE DUE TO BETTER MODEL INITIALIZATION AT 850 AND 700 MB. BASED ON THE GFS... EXPECT FRONT TO EXTEND FROM KOMA TO KFCL BY 21Z THIS AFTERNOON. ACCORDINGLY...EXPECT TEMPERATURES TO AGAIN REACH INTO THE LOWER 100S AHEAD OF THE FRONT. INFRARED IMAGERY SHOWS DECENT HIGH LEVEL CLOUDS FROM SOUTH DAKOTA TO COLORADO...BUT WATER VAPOR IMAGERY SHOWS DRY AIR STILL HOLDING ACROSS THE FORECAST AREA. SO...FEEL MID LEVEL CLOUDS WILL HAVE LITTLE IMPACT HERE ON THE TEMPERATURES. CAP WILL HOLD FOR MUCH OF THE AFTERNOON...BUT WILL BREAK AS MID LEVEL COOLING ARRIVES OVER YUMA COUNTY COLORADO AND THE NEBRASKA COUNTIES AFTER 21Z. ENOUGH SURFACE CONVERGENCE WILL BE PRESENT NEAR FRONT TO PRODUCE SCATTERED THUNDERSTORMS. BEST INSTABILITY AND SHEAR WILL OCCUR NORTH OF THE AREA THIS AFTERNOON...THOUGH SHEAR IN THE LOWEST 3 KM WILL INCREASE FURTHER SOUTH DURING THE EVENING. FOR NOW...WILL CONFINE FIRST PERIOD MENTION OF STORMS OVER THE EXTREME NORTHERN PART OF THE AREA. AS FRONT CONTINUES SOUTH DURING THE EVENING...THE CHANCE OF STORMS WILL INCREASE OVER ENTIRE AREA. CONVECTION THAT DEVELOPS OVER THE FRONT RANGE WILL MOVE EAST ON 500 MB WINDS...PLUS LOW LEVEL WINDS WILL BECOME UPSLOPE. FINALLY...THE SOUTHERN PART OF AREA WILL BE IMPACTED BY LOW LEVEL JET THROUGH MIDNIGHT. WITH LOW LEVEL CONVERGENCE AND DECENT LAPSE RATES...WILL MENTION HIGH POPS TONIGHT. WOULD NOT BE SURPRISED TO SEE A FEW SEVERE STORMS ALONG THE FRONT. CONTINUED UPSLOPE FLOW WILL PROVIDE A CHANCE OF SHOWERS THURSDAY. TEMPERATURE PROGS INDICATE A LARGE DECREASE OF TEMPERATURES... PERHAPS 25-30 DEGREES COOLER THURSDAY. DRIER AIR AND WARMER AIR ARRIVES FRIDAY. IN THE EXTENDED...MADE ONLY MINOR ADJUSTMENTS AS RIDGE REBUILDS OVER THE CENTRAL UNITED STATES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. NE...NONE. CO...NONE. && $$ JRM/MENTZER ks AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE BURLINGTON VT 1138 AM EDT WED AUG 3 2005 HAVE OPTED TO UPDATE THE GOING FCST FOR MOSTLY SOME FIRST PERIOD CHANGES. .SYNOPSIS... FRONTAL BOUNDARY TO REMAIN ACRS MUCH OF THE SRN/WRN FA TODAY. .SHORT TERM (REST OF TODAY THROUGH TONIGHT)... LATEST RUC DATA SHOWS TEMPS TO GET UP INTO THE M70S-L90S TODAY WITH NORTHERLY SFC WINDS AT 5-15 KTS. FEW TWEAKS TO FIRST PERIOD TEMPS/WINDS BASED ON THIS DATA AND MESONET OBS. SOME MID-LVL (AND LOW-LVL) MSTR TO AFFECT THE FA TODAY. LOW-LVL LAPSE RATES TO BE HI ACRS THE FA TODAY. PW VALUES ACRS THE FA LOOK TO RANGE FROM AROUND 0.3" UP ACRS NE VT TO AS MUCH AS 1.6" ACRS THE SW PORTION OF THE FA TODAY. RUC SHOWS CLDS/PCPN TO PERSIST IN AND AROUND THE FRONTAL BOUNDARY ACRS MUCH OF THE FA FOR AT LEAST THE REST OF TODAY. SAT/RADAR TRENDS HAVE BEEN SHOWING THIS FOR A WHILE NOW AS WELL. ENVIRONMENT ACRS THE FA TODAY APPEARS TO BE AT LEAST MODERATELY SHEARED WITH WET-BULB ZERO HTS OF AROUND 10.0 KFT. MAX CAPES ACRS THE FA LOOK TO BE AOB 3000 J/KG (ACRS THE WRN TIER ZONES ONLY) TODAY. WITH AT LEAST SOME AMT OF MID-LVL DRY AIR/DECENT LAPSE RATES AVAILABLE ACRS MUCH OF THE FA TODAY AND BEST INSTABILITY ACRS MUCH OF THE WRN TIER ZONES...HAVE ADDED SOME ENHANCED WORDING TO SOME OF THE ZONE GROUPINGS THAT STAND TO HAVE THE BEST CHC AT SEEING SOME CONVECTION FOR THE REST OF TODAY. +RA AND GUSTY WINDS APPEAR TO BE THE MAIN THREAT. WIDESPREAD SVR WX LOOKS IFFY ATTM...SO NO SPS FOR NOW. MADE A FEW MINOR TWEAKS TO THE TONITE PERIOD MOSTLY TO TRY AND BLEND BETTER WITH THE ABOVE CHANGES. ALL FINAL PRODUCTS ALREADY ISSUED. LATER... .HYDROLOGY... 24-HR QPE (THRU 14-15Z TODAY) ACRS THE FA APPEARS TO BE MOSTLY BE AOB 0.25"...WITH SOME ISOLATED 1-2" AMTS ACRS THE NRN TIER FROM YESTERDAY/S CONVECTION. LATEST NERFC FFG VALUES APPEAR TO BE MOSTLY ABOVE 2"...BUT WILL NEED TO WATCH FOR ANY TRAINING OF CELLS BY LATER TODAY. .PREVIOUS DISCUSSION... (ISSUED 443 AM EDT WED AUG 3 2005) SHORT TERM (REST OF TODAY)... UPDATE THIS MORNING TO ENLARGE AREA OF CHC POPS IN NORTHERN NY... WHICH ARE HOLDING TOGETHER AND SHIFTING FURTHER EAST THAN PREVIOUSLY ANTICIPATED. STORMS APPEAR TO BE FEEDING ON SOME LEFTOVER INSTABILITY...AND WEAK CONVERGENCE IN THE SURFACE WIND FIELD. GIVEN CURRENT TRACK...AND TENDENCY TO STAY TOGETHER...HAVE ENLARGED AREA OF MORNING CHC POPS INTO THE SOUTHERN CHAMPLAIN VALLEY/WESTERN ADDISON AND RUTLAND COUNTIES IN VT. PREVIOUS DISCUSSION... (ISSUED 308 AM EDT WED AUG 3 2005) SHORT TERM (TODAY THROUGH FRIDAY)... CURRENT RADAR/SATELLITE PIX SHOWING SHOWERS/TSTMS LINED UP IN THE NORTHWEST FLOW...NORTH OF THE SAINT LAWRENCE VALLEY...MOVING SOUTHWEST. ONE SHOWER JUST NORTH OF MASSENA...AND ANOTHER THUNDERSTORM CLUSTER FURTHER N. PUT IN CHC SHOWERS/TSTMS FOR FRANKLIN/ST. LAWRENCE COUNTIES THIS MORNING. OTHERWISE...DRY FCST FOR TODAY. CAPES IN THE AFTERNOON GET ABOVE 1000 J/KG IN SOME SPOTS...BUT ENOUGH OF A CAP...AND LACK OF FORCING TO GET CONVECTION GOING. SHOULD ALSO BE INHIBITED BY DEVELOPING UPPER RIDGE AS THE LOW TO THE NORTHEAST BEGINS TO PULL OUT OF THE AREA. LATE THURSDAY INTO FRIDAY...A COLD FRONT MOVES TO AND THRU THE FORECAST AREA. PUT IN SLGT CHC POPS CHAMPLAIN VALLEY/VT LATE THURSDAY AS MODELS HINTING AT WEAK PREFRONTAL TROUGH...AS IS OFTEN THE CASE. WHERE THE TROF COINCIDES WITH AFTN HEATING COULD GET SOME PREFRONTAL SHOWERS/TSTMS. MAIN SHOW WILL BE ALONG FRONT...ALTHOUGH TIMING SEEMS TO BE MORE IN THE MORNING. FRONTS MOVING THRU THE REGION OFTEN GET HUNG UP...SO I KEPT CHC POPS IN A LITTLE LONGER THAN GFS/NAM QPF FORECAST INDICATE. TEMPS...WARM TODAY...AND EVEN WARMER ON THURS WITH HIGHS 90 TO LOWER 90S IN CHAMPLAIN/ST LAWRENCE VALLEYS. GIVEN THAT THIS IS THE FIRST WEEK OF AUGUST...COULD THIS BE LAST TIME WE SEE 90 THIS SUMMER SEASON? WE'LL SEE. LONG TERM (FRIDAY NIGHT THROUGH TUESDAY)... MADE SOME ADJUSTMENTS TO POP/WX GRIDS FRIDAY NIGHT INTO SATURDAY TO TRANSITION THE EXIT OF THE FRONT. OTHERWISE...DRY FCST TO CONTINUE AS ZONAL FLOW SETS UP...AND MAIN BRANCH OF THE WESTERLIES KEEP STORM TRACKS TO THE NORTH. AVIATION... AVIATION CONCERN THIS MORNING WL BE FOG AT MPV/SLK...THEN THE DEVELOPMENT OF TRW ACTIVITY THIS AFTERNOON. BASED ON LIGHT WINDS... CLR SKIES...AND PREVIOUS NITE TRENDS WL MENTION FOG AT MPV/SLK THRU 12Z. OTHERWISE...EXPECT VFR CONDITIONS AT BTV/MSS WITH MAYBE A TEMPO GROUP BTWN 10-12Z OF MVFR WITH BR. EXPECT LIMITED AFTERNOON TRW ACTIVITY BASED ON MID/UPPER LVL RIDGE BUILDING ACRS FA AND LIMITED ULVL FORCING. HOWEVER...EXPECT CU TO DEVELOP AROUND 18Z AS CONVECTIVE TEMPS ARE REACHED AND LLVL INSTABILITY INCREASES AS CAPES APPROACH 1500 J/KG. GIVEN...ISOLATED NATURE OF CONVECTION TODAY...WL KEEP OUT OF TAFS ATTM. .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ UPDATED SYNOPSIS/SHORT TERM/HYDROLOGY...MURRAY vt AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 930 AM EDT WED AUG 3 2005 .SHORT TERM (REST OF TODAY)... CURRENT FORECAST LOOKS GOOD AS WE CONTINUE WITH ANOTHER DAY OF BENIGN WEATHER. NOT EXPECTING TO MAKE ANY CHANGES. HIGH PRESSURE DOMINATES THE MID ATLANTIC. WILL KEEP A SLIGHT CHANCE OF PRECIP ACROSS THE SOUTHERN TIER OF COUNTIES. WEAK CAP AT 600-700 MB...ALONG WITH DRY AIR ALOFT...IN WAL AND LWX SOUNDINGS WILL HELP TO KEEP PRECIP CHANCES LOW TO THE NORTH. WITHOUT ANY SIGNIFICANT BOUNDARIES OR LIFT...EXPECT THAT WE WILL SEE WIDELY SCT SHOWERS ALONG THE WEAK SURFACE CONVERGENCE WITH THE THERMAL TROUGH FOR THE EXTREME SOUTHERN COUNTIES LATE THIS AFTERNOON. ALS && .PREVIOUS DISCUSSION... (ISSUED 730 AM EDT WED AUG 3 2005) UPDATE...SUN BURNING OFF PATCHY FOG...W/ ONLY ISO PATCHES OF IFR OR LWR VSBY REMAINING. WILL UPDATE THE ZONES SHORTLY TO REFRESH THE WORDING/REMOVE FOG MENTION. _______________PREV AFD BELOW_______________ SHORT TERM (TODAY THROUGH FRIDAY NIGHT)...QUIET ERLY MRNG ASIDE FROM SOME PATCHY FOG...TEMPS MAINLY IN 70S. DEW PTS (MAINLY 70 TO 75) ARE A LITTLE HIGHER THAN YSDY AT THIS TIME. WK SFC HIGH PRES WILL REMAIN IN CONTROL TODAY...BUT EXPECT A THERALLY INDUCED LEE TROF TO DEVELOP BY AFTN. THIS FEATURE WILL BE WEAK...BUT W/ DEW PTS JUST A BIT HIGHER...RUC SNDGS SHOWING K-INDICES APPRCHNG UPR 30/NEAR 40...AND TEMPS CLIMBING INTO MID 90S COULD SEE A STRAY SHOWER/TSTM DEVELOP BY LATE AFTN. HAVE A SLGT CHC FOR SRN PIEDMNT/INLAND NC IN ZONE OF BEST LOW LVL CONV. OTHERWISE...STILL LOOKS A BIT TOO CAPPED/AND DRY ABOVE 700 MB FOR ANY ORGANIZED PRECIP. THU/FRI...NEXT SHORTWAVE DIVES SEWD FROM HUDSON BAY UPR LOW INTO UPR MIDWEST...AMPLIFYING RIDGING ACRS SCNRTL/SE CONUS. TEMPS THU WILL WARM INTO MID/UPR 90S FOR INLAND VA/NC (A LITTLE COOLER ON COAST). STAYED A BIT BLO MAV GDNC WHICH HAS NEAR 100 IN WRN ZONES THU AS DOWNSLOPING WILL BE LMTD AND H8 TEMPS TOP OUT ABOUT 19C. BY FRIDAY...FRONTAL BNDRY/UPR SHORTWV DRIFTS CLOSER TO REGION...BUT STRONGER SW FLOW WILL HELP TRANSPORT MID 90S TO COASTAL AREAS LIKE ORF. DEEPER MSTR LOOKS LMTD AS WLY DOWNSLOPING DEVELOPS IN 900 TO 700 MB LYR. WILL CARRY CHC POPS IN NRN PIEDMNT...TAPERED TO SCHC ELSEWHERE BY LATE AFTN. A BIT MORE LOW LVL CONV/UPR SUPPORT MOVES OVERHEAD DURING EVENG SO HAVE LOW CHC POPS ALL ZONES BY THEN. LONG TERM (SATURDAY THROUGH TUESDAY)...COOLED TEMPS A BIT ON SATURDAY...HIGHS MAINLY IN MID/UPR 80S W/ SOMEWHAT MORE CLOUD CVR AS FRONTAL BNDRY STALLS ACRS VA. ALOT OF UNCERTAINTY AS TO EXACT LOCATION OF BNDRY SO WILL KEEP CHC POPS GOING SAT INTO LATE MON NGT IN VCNTY OF FRONT. AVIATION... WEAK BNDRY LAYER MIXING HAS PREVENTED FOG FROM BCMG TOO WIDESPREAD/DENSE EARLY THIS MORN. SOME THICKER PATCHES AROUND BEFORE SUNRISE...BUT MOST TAF SITES WL MAINTAIN AT LEAST MVFR VSBYS (EXCEPT TEMPO IFR/LIFR AT SBY) WITH IMPROVING CONDS TO VFR ALL AREAS AN HOUR OR 2 AFTER SUNRISE. MARINE... BENIGN BOATING CONDS EXPECTED NEXT FEW DAYS. LIGHT SW WINDS SHIFT N AS WEAK SFC TROF DROPS THRU MARINE AREA THIS MORN. LIGHT ONSHORE FLOW DEVELOPS THIS AFTN AS PRES GRADIENT BECOMES DIFFUSE. WINDS BCMG MORE S/SW OVR MARINE AREA ON THU DUE WEAK LEESIDE TROF DEVELOPMENT BUT SPEEDS GREATER THAN 10 KTS IN THE BAY/SOUND AND 15 KTS ALONG CSTL WTRS HARD TO COME BY. SW WINDS PICK UP SOME ON FRI AHEAD APPROACHING COLD FRONT. AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. $$ UPDATE...BROWN SHORT TERM/LONG TERM...BROWN && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ SHORT TERM...09 va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 730 AM EDT WED AUG 3 2005 .UPDATE...SUN BURNING OFF PATCHY FOG...W/ ONLY ISO PATCHES OF IFR OR LWR VSBY REMAINING. WILL UPDATE THE ZONES SHORTLY TO REFRESH THE WORDING/REMOVE FOG MENTION. _______________PREV AFD BELOW_______________ .SHORT TERM (TODAY THROUGH FRIDAY NIGHT)...QUIET ERLY MRNG ASIDE FROM SOME PATCHY FOG...TEMPS MAINLY IN 70S. DEW PTS (MAINLY 70 TO 75) ARE A LITTLE HIGHER THAN YSDY AT THIS TIME. WK SFC HIGH PRES WILL REMAIN IN CONTROL TODAY...BUT EXPECT A THERALLY INDUCED LEE TROF TO DEVELOP BY AFTN. THIS FEATURE WILL BE WEAK...BUT W/ DEW PTS JUST A BIT HIGHER...RUC SNDGS SHOWING K-INDICES APPRCHNG UPR 30/NEAR 40...AND TEMPS CLIMBING INTO MID 90S COULD SEE A STRAY SHOWER/TSTM DEVELOP BY LATE AFTN. HAVE A SLGT CHC FOR SRN PIEDMNT/INLAND NC IN ZONE OF BEST LOW LVL CONV. OTHERWISE...STILL LOOKS A BIT TOO CAPPED/AND DRY ABOVE 700 MB FOR ANY ORGANIZED PRECIP. THU/FRI...NEXT SHORTWAVE DIVES SEWD FROM HUDSON BAY UPR LOW INTO UPR MIDWEST...AMPLIFYING RIDGING ACRS SCNRTL/SE CONUS. TEMPS THU WILL WARM INTO MID/UPR 90S FOR INLAND VA/NC (A LITTLE COOLER ON COAST). STAYED A BIT BLO MAV GDNC WHICH HAS NEAR 100 IN WRN ZONES THU AS DOWNSLOPING WILL BE LMTD AND H8 TEMPS TOP OUT ABOUT 19C. BY FRIDAY...FRONTAL BNDRY/UPR SHORTWV DRIFTS CLOSER TO REGION...BUT STRONGER SW FLOW WILL HELP TRANSPORT MID 90S TO COASTAL AREAS LIKE ORF. DEEPER MSTR LOOKS LMTD AS WLY DOWNSLOPING DEVELOPS IN 900 TO 700 MB LYR. WILL CARRY CHC POPS IN NRN PIEDMNT...TAPERED TO SCHC ELSEWHERE BY LATE AFTN. A BIT MORE LOW LVL CONV/UPR SUPPORT MOVES OVERHEAD DURING EVENG SO HAVE LOW CHC POPS ALL ZONES BY THEN. && .LONG TERM (SATURDAY THROUGH TUESDAY)...COOLED TEMPS A BIT ON SATURDAY...HIGHS MAINLY IN MID/UPR 80S W/ SOMEWHAT MORE CLOUD CVR AS FRONTAL BNDRY STALLS ACRS VA. ALOT OF UNCERTAINTY AS TO EXACT LOCATION OF BNDRY SO WILL KEEP CHC POPS GOING SAT INTO LATE MON NGT IN VCNTY OF FRONT. && .AVIATION... WEAK BNDRY LAYER MIXING HAS PREVENTED FOG FROM BCMG TOO WIDESPREAD/DENSE EARLY THIS MORN. SOME THICKER PATCHES AROUND BEFORE SUNRISE...BUT MOST TAF SITES WL MAINTAIN AT LEAST MVFR VSBYS (EXCEPT TEMPO IFR/LIFR AT SBY) WITH IMPROVING CONDS TO VFR ALL AREAS AN HOUR OR 2 AFTER SUNRISE. && .MARINE... BENIGN BOATING CONDS EXPECTED NEXT FEW DAYS. LIGHT SW WINDS SHIFT N AS WEAK SFC TROF DROPS THRU MARINE AREA THIS MORN. LIGHT ONSHORE FLOW DEVELOPS THIS AFTN AS PRES GRADIENT BECOMES DIFFUSE. WINDS BCMG MORE S/SW OVR MARINE AREA ON THU DUE WEAK LEESIDE TROF DEVELOPMENT BUT SPEEDS GREATER THAN 10 KTS IN THE BAY/SOUND AND 15 KTS ALONG CSTL WTRS HARD TO COME BY. SW WINDS PICK UP SOME ON FRI AHEAD APPROACHING COLD FRONT. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...NONE. && $$ UPDATE...BROWN SHORT TERM/LONG TERM...BROWN AVIATION/MARINE...CULLEN va AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE JACKSONVILLE FL 150 PM EDT WED AUG 3 2005 .SHORT TERM...COMPLEX WX PATTERN CONTINUES WITH SOME VARIETY OF SHEAR AXIS PRESENT FROM THE SURFACE TO THE MID LEVELS OF THE ATMOSPHERE. THIS...ALONG WITH THE SEABREEZE...IS PROVIDING AN ABUNDANCE OF FOCUSING MECHANISMS FOR CONVECTION. PLENTY OF INSTABILITY WITH NO CIN PRESENT IS RESULTING IN WIDESPREAD WEAK STORM FORMATION. EXPECT FOR THE REMAINDER OF THE EVENING...BEST CONCENTRATION OF STORMS WILL BE IN THE WESTERN PORTIONS OF THE GEORGIA FORECAST AREA WHERE STEERING FLOW IS EASTERLY TO THE EASTERN SECTIONS OF THE FLORIDA ZONES WHERE THE FLOW IS MORE WESTERLY. EAST TO NORTHEAST PUNCH OVER THE GEORGIA ZONES SHOULD ALLOW SOME OF THE DRIER AIR NOTED NORTH OF THE CWA TO MAKE ITS WAY SOUTHWARD ALONG THE GEORGIA COAST. BIGGEST QUESTION FOR THE SHORT TERM IS WILL THIS DRY AIR CONTINUE ITS MARCH THROUGH THE AREA OR SHIFT BACK NORTH AS THE GFS SUGGEST. I HAVE SEEN MY SHARE OF MODEL DISCREPANCIES...BUT THIS IS A BIG ONE WITH POPS SPREAD BY SOME 70 TO 80 PERCENT FOR THURSDAY AND FRIDAY. PROBLEM HAS BEEN THERE IS REALLY NOT TOO MUCH IN THE ANALYSIS THAT WOULD ALLOW ME TO HEAVILY FAVOR ONE MODEL OVER ANOTHER. I DO NOTE FROM THE RUC ANALYSIS THAT THERE IS SOME DRY AIR TO THE NORTH OF THE CWA AND MORE IN LINE WITH THE NAM...BUT GFS HAS DONE A BETTER JOB WITH PRECIP COVERAGE THUS FAR THIS AFTERNOON. LOOKING AT THE NAM...IT DOES SEEM TO DRY OUT THE AIRMASS QUICKLY FOR NO APPARENT REASON IN ADDITION TO THE ADVECTIVE COMPONENT IT IS SHOWING. WOULD TEND TO LEAN TOWARD THE WETTER GFS BASED ON RECENT TRENDS OF THE NAM TO BE TOO AGGRESSIVE WITH THESE DRY FEATURES...BUT SIMPLY CANNOT GO WITH THE 70 AND 80 POPS SHOWN BY THE GFS WHEN THE ETA SHOWS NEAR 20. THEREFORE...AM PLANNING ON USING A BLEND AND HAVING A STEEP GRADIENT FROM NORTHEAST TO SOUTHWEST INDICATING AT LEAST SOME DRY AIR WORKING IN FROM THE NORTH. HOPEFULLY MODELS WILL COME INTO BETTER AGREEMENT FOR THE MORNING PACKAGE. AS MENTIONED...THESE LARGE DISCREPANCIES CONTINUE RIGHT INTO THE FIRST HAVE OF THE WEEKEND WITH THE NAM DRYING THE ATMOSPHERE OUT ENOUGH TO HAVE NIL POPS OVER THE AREA. WILL AGAIN USE A BLEND BUT HAVE A DEFINITE DOWNWARD TREND IN THE POPS THROUGH SATURDAY. .LONG TERM...GFS FORMS LOW PRESSURE OVER THE DEEP SOUTH THE LATTER HALF OF THE WEEKEND. WILL STAY AWAY FROM THIS SOLUTION FOR NOW AND STAY WITH THE MORE CONSERVATIVE NAM WITH NEAR CLIMO POPS AND TEMPS. && .MARINE...NNE FLOW CONTINUES OVER THE WATERS THIS AFTERNOON BETWEEN LOW PRESSURE OFFSHORE OF THE SE COAST AND HIGH PRESSURE OVER THE NE CONUS. MODELS ARE NOT REALLY INDICATING MUCH OF A SURGE...BUT BUOYS REPORT WINDS 10-15 GUSTS TO NEAR 20 KT AT TIMES OVER SC AND GA WATERS. SEAS ARE RUNNING 2-4 FT. WILL INCREASE WINDS THIS EVENING TO 10-15 KTS...THEN AS WINDS BECOME MORE ELY THU EXPECT THE PRESSURE GRADIENT WILL WEAKEN WITH SPEEDS DROPPING TO 10 KTS OR LESS THROUGH THE REMAINDER OF THE FORECAST PERIOD AS HIGH PRESSURE OVER THE ATLANTIC BEGINS TO DOMINATE. SEAS 2-4 FT. && .PRELIMINARY POINT TEMPS/POPS... AMG 71 91 72 90 / 40 40 30 40 SSI 76 88 77 88 / 30 30 20 30 JAX 72 89 73 89 / 60 50 30 40 SGJ 73 87 74 88 / 60 50 30 40 GNV 71 91 71 91 / 60 50 30 40 OCF 71 91 72 91 / 60 50 30 40 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. MARINE...NONE. && $$ PUBLIC...DEESE MARINE/FIRE WX...ENYEDI fl AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OHIO 345 PM EDT WED AUG 3 2005 .AVIATION (18Z-18Z)... UPDATED CLE TAF BECAUSE A FEW SHOWERS DEVELOPING ALONG THE LAKE BREEZE FROM SOUTHERN GEUAGA INTO CUYAHOGA COUNTY. MIGHT SEE A RUMBLE OF THUNDER OR TWO THIS AFTERNOON...BUT THAT'S ABOUT IT. SHOULD END AROUND SUNSET. HIGH PRESSURE WILL REMAIN IN CONTROL NEXT 24 HOURS. EXPECT SOME MVFR VIS HZ/BR DEVELOPING OVERNIGHT...BUT DON'T THINK IT WILL QUITE AS BAD AS THIS MORNING SINCE GRADIENT WILL BE A LITTLE STRONGER SO DON'T EXPECT WINDS TO DECOUPLE. COLD FRONT ACROSS WISCONSIN INTO IOWA WILL BE PUSHING INTO CENTRAL LOWER MICHIGAN BY THIS TIME TOMORROW. EXPECT SOME SCATTERED TSRA DEVELOPMENT AHEAD OF FRONT APPROACHING NW OH BY THIS TIME TOMORROW. && .SHORT TERM(TONIGHT-SAT)... A VERY DRY ATMOSPHERE CONTINUES ACROSS THE LOWER LAKES. 12Z SOUNDINGS FROM DTX AND PBZ SHOWED PRECIPITABLE WATER VALUES OF 1.02 AND 1.21 RESPECTIVELY. ALTHOUGH SOME MOISTURE IS BEGINNING TO FILTER INTO THE AREA AS RETURN FLOW SETS UP...PRECIPITABLE WATER VALUES ARE STILL LESS THAN 1.4 INCHES. AREA STILL UNDER RIDGING ALOFT...WITH AN UPR S/WV OVR THE UPR MIDWEST WITH THE ASSOCIATED COLD FRONT EXTENDING FROM MN TO NEBRASKA. A FEW STORMS HAVE POPPED UP ACROSS THE AREA WITHIN THE PAST HOUR. RUC ANALYSIS FROM THE AREA SUGGEST SBCAPE OF 1500-2000 J/KG ACROSS THE REGION WITH MINIMAL CIN. WITH THE CU THAT HAVE DEVELOPED...IT IS POSSIBLE THAT AN ISOLATED STORM MAY DEVELOP THIS EVENING AS WATER VAPOR AND RUC ANALYSIS SHOWS A WK IMPULSE MVNG THRU OHIO. IF THERE WAS NOT ACTIVITY OUT THERE ALREADY...I WOULD PROBABLY NOT PUT ANY POPS IN THE FCST THIS EVENING SINCE THE SYNOPTIC SUPPORT IS MINIMAL. WL THEREFORE PLACE A 20 POP ACROSS THE ENTIRE AREA (XCP THE LAKE) THIS EVENING JUST IN CASE. SEE NO REASON TO MAKE MAJOR CHANGES TO THE GOING FCST. OTHER THAN THE SCHC OF A STORM THIS EVENING...THE SFC HIGH PRES IN PLACE WILL KEEP THE WX QUIET AGAIN TONIGHT. AS THE HIGH SHIFTS EWD...DWPTS SHOULD SLOWLY CREEP UP IN SLY RETURN FLOW. SO DESPITE THE LOW-MID 60S DWPTS ATTM...EXCEPT THE COMBO OF LOSS OF MIXING COMBINED WITH WK LOW LVL MOISTURE ADVECTION AND A SLIGHT INCREASE IN CLDS TO ALLOW THE DWPTS TO REACH THE MID-UPR 60S BY MRNG. THIS WL ALLOW THE MIN TEMPS TONIGHT TO STAY IN THE UPR 60S AND PERHAPS SOME TEMPS AROUND 70. FROPA TIMING THU EVENING IS GENERALLY SIMILAR IN THE GFS AND NAM. BOTH MDLS SHOW HIGH INSTABILITY AHD OF THE FNT WITH SBCAPE VALUES APPROACHING 2500 J/KG. WITH A STRONG FRONT LIKE THIS AND THE TEMP CONTRAST ACROSS THE FRONT ONE WOULD THINK THE LIKELIHOOD OF SVR WX WAS A LITTLE HIGHER THAN USUAL. HOWEVER...THIS MAY NOT BE THE CASE IN THIS EVENT. FIRST...THE STRONG WLY MID LVL FLOW GENERALLY STAYS N OF THE AREA UNTIL AFTER FROPA. IN FACT...SHEAR VECTORS FOR MUCH OF THE DAY TMRW STAY OUT OF THE NE...WHICH IS NOT FAVORABLE FOR SVR WX. THE H5 RIDGE AXIS ONLY SHIFTS SLOWLY SWD THRU THE DAY AND MUCH OF THE AREA STAYS IN UPR LVL ANTI-CYCLONIC FLOW THRU THE AFTN. PLUS...THE NAM (AND THE GFS TO AN EXTENT) SUGGEST WEAKENING CONVERGENCE ALONG THE FRONT AS THE BEST UPR DYNAMICS LIFT N INTO MI. FINALLY...UNLESS THE FRONT SPEEDS UP...THE FRONTAL WILL GENERALLY PASS OVER THE AREA IN THE NIGHTTIME WHICH WOULD NOT BE FAVORABLE FOR INSTABILITY. HOWEVER...WITH ALL OF THIS SAID...I DO THINK THERE WILL BE AT LEAST SCT STORMS ALONG THE FRONT. PRECIPITABLE WATER VALUES POOL ALONG THE FRONT TO OVER 2.0 INCHES SO MOISTURE DOES INCREASE IMMEDIATELY AHD OF THE FRONT. I AM JUST UNSURE OF THE SEVERITY OF ANY STORM THAT DEVELOPS...AS THE KINEMATIC PROFILES WILL BE GENERALLY WK BUT THE THERMODYNAMIC PROFILE WL BE VERY FAVORABLE. SPC HAS PLACED MOST OF THE FORECAST AREA UNDER A SLIGHT RISK FOR THU. IF SVR WX DOES DEVELOP THU AFTN/EVENING...STRONG WINDS WL BE THE GREATEST RISK AS SFC DELTA THETA-E VALUES APPROACH 25C. WL THEREFORE GO WITH CHC POPS THU AFTN IN TOL AND LATE THU AFTN CLE AND FDY. AM A LITTLE CONCERNED THAT A FEW POP UP STORMS MAY DEVELOP THU AFTN OVER THE WEST AS INCREASED Q-VECT CONV AND THE RIGHT ENTRANCE REGION OF THE JET MOVES OVER THE WRN PART OF THE AREA. WL GO WITH 50 POPS ALL AREAS THRU NIGHT. DO THINK IT WILL DRY OUT RATHER QUICKLY LATE THU NIGHT INTO FRIDAY MRNG BEHIND THE FRONT AS HIGH PRES QUICKLY BUILDS INTO THE REGION. GFS SUGGESTS THAT THE FRONT WL HANG UP FURTHER N THAT THE NAM. THIS ALLOWS THE GFS TO KEEP CLDS AND EVEN SOME LIGHT QPF ACROSS THE FORECAST AREA INTO FRI EVENING. DO NOT BELIEVE THIS SOLN ATTM AS THE FRONT SHOULD HAVE ENOUGH MOMENTUM TO MAKE IT FAR ENOUGH SOUTH TO CLEAR OUT THE AREA BY FRI EVENING. SHOULD BE A QUIET SAT WITH HIGH PRES OVERHEAD...MOSTLY SUNNY SKIES AND NEAR OR MAYBE SLIGHTLY BELOW NORMAL TEMPS. 850MB TEMPS CONTINUE AROUND +20C ON THU...BUT SWLY SFC WINDS WILL BE STRONGER. THIS SHOULD ALLOW FOR TEMPS TO ONCE AGAIN RISE WELL INTO THE 90S WITH INCREASING HUMIDITY. EXPECT HEAT INDEX VALUES CLOSE TO 100. MUCH COOLER ON FRIDAY WITH TEMPS IN THE UPR 70S/LOWER 80S. && .LONG TERM (SUN THRU WED)... CONFIDENCE IN MEDIUM RANGE FCST NOT AS HIGH AS IT HAS BEEN LATELY. EXTENDED MDLS SUGGEST A MORE AMPLIFIED PATTERN SETTING UP ACROSS NORTH AMERICA. MDLS SUGGEST THAT A TROUGH WL DIG INTO THE NWRN STATES MON-WED...BUT THE AMPLITUDE AND TIMING OF THIS UPR TROUGH IS OF DEBATE. THE OP GFS AND UKMET SUGGEST THE SHORT WAVE DIGGING INTO THE PAC NW MON AND TUE WITH RISING HEIGHTS ACROSS THE REGION. ECMWF SUGGESTS A WEAKER TROUGH OVER THE PAC NW WITH LESS HEIGHT RISES ACROSS THE REGION. THERE IS SOME SUPPORT FOR THIS SOLN FROM SVRL GFS ENS MEMBERS...SO THIS CANNOT BE RULED OUT. IN FACT...WHEN LOOKING AT SPAGHETTI PLOTS FROM THE GFS ENS...THERE ARE SOME MEMBERS THAT ARE TOTALLY OUT OF PHASE IN THE MON/TUE TIME PERIOD. SO...WITH CONFIDENCE BEING A LITTLE LOWER THAN IT HAS BEEN LATELY...HAVE OPTED TO GO WITH A GENERAL ENSEMBLE MEAN FOR TEMPS...PERHAPS TRENDING A LITTLE HIGHER THAN THE ENSEMBLE MEAN. HIGHS GENERALLY IN THE MID 80S...LOWS IN THE MID-UPR 60S. GFS ALSO HAS PCPN EACH DAY MON-WED ACROSS OHIO. WITH THE MDL SHOWING A SFC RIDGE ACROSS THE AREA IT SEEMS HARD TO BELIEVE THAT THERE WILL BE MUCH PCPN. WL LEAVE IT DRY FOR NOW. MAY NEED SOME SMALL POPS AS THE TIME NEARS...BUT FOR NOW A DRY FCST SEEMS REASONABLE GIVEN THE PATTERN. && .CLE WATCHES/WARNINGS/ADVISORIES... .OH...NONE. .PA...NONE. $$ SHORT TERM...MRD LONG TERM...MRD AVIATION...DJB oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE CLEVELAND OHIO 335 PM EDT WED AUG 3 2005 .SHORT TERM(TONIGHT-SAT)... A VERY DRY ATMOSPHERE CONTINUES ACROSS THE LOWER LAKES. 12Z SOUNDINGS FROM DTX AND PBZ SHOWED PRECIPITABLE WATER VALUES OF 1.02 AND 1.21 RESPECTIVELY. ALTHOUGH SOME MOISTURE IS BEGINNING TO FILTER INTO THE AREA AS RETURN FLOW SETS UP...PRECIPITABLE WATER VALUES ARE STILL LESS THAN 1.4 INCHES. AREA STILL UNDER RIDGING ALOFT...WITH AN UPR S/WV OVR THE UPR MIDWEST WITH THE ASSOCIATED COLD FRONT EXTENDING FROM MN TO NEBRASKA. A FEW STORMS HAVE POPPED UP ACROSS THE AREA WITHIN THE PAST HOUR. RUC ANALYSIS FROM THE AREA SUGGEST SBCAPE OF 1500-2000 J/KG ACROSS THE REGION WITH MINIMAL CIN. WITH THE CU THAT HAVE DEVELOPED...IT IS POSSIBLE THAT AN ISOLATED STORM MAY DEVELOP THIS EVENING AS WATER VAPOR AND RUC ANALYSIS SHOWS A WK IMPULSE MVNG THRU OHIO. IF THERE WAS NOT ACTIVITY OUT THERE ALREADY...I WOULD PROBABLY NOT PUT ANY POPS IN THE FCST THIS EVENING SINCE THE SYNOPTIC SUPPORT IS MINIMAL. WL THEREFORE PLACE A 20 POP ACROSS THE ENTIRE AREA (XCP THE LAKE) THIS EVENING JUST IN CASE. SEE NO REASON TO MAKE MAJOR CHANGES TO THE GOING FCST. OTHER THAN THE SCHC OF A STORM THIS EVENING...THE SFC HIGH PRES IN PLACE WILL KEEP THE WX QUIET AGAIN TONIGHT. AS THE HIGH SHIFTS EWD...DWPTS SHOULD SLOWLY CREEP UP IN SLY RETURN FLOW. SO DESPITE THE LOW-MID 60S DWPTS ATTM...EXCEPT THE COMBO OF LOSS OF MIXING COMBINED WITH WK LOW LVL MOISTURE ADVECTION AND A SLIGHT INCREASE IN CLDS TO ALLOW THE DWPTS TO REACH THE MID-UPR 60S BY MRNG. THIS WL ALLOW THE MIN TEMPS TONIGHT TO STAY IN THE UPR 60S AND PERHAPS SOME TEMPS AROUND 70. FROPA TIMING THU EVENING IS GENERALLY SIMILAR IN THE GFS AND NAM. BOTH MDLS SHOW HIGH INSTABILITY AHD OF THE FNT WITH SBCAPE VALUES APPROACHING 2500 J/KG. WITH A STRONG FRONT LIKE THIS AND THE TEMP CONTRAST ACROSS THE FRONT ONE WOULD THINK THE LIKELIHOOD OF SVR WX WAS A LITTLE HIGHER THAN USUAL. HOWEVER...THIS MAY NOT BE THE CASE IN THIS EVENT. FIRST...THE STRONG WLY MID LVL FLOW GENERALLY STAYS N OF THE AREA UNTIL AFTER FROPA. IN FACT...SHEAR VECTORS FOR MUCH OF THE DAY TMRW STAY OUT OF THE NE...WHICH IS NOT FAVORABLE FOR SVR WX. THE H5 RIDGE AXIS ONLY SHIFTS SLOWLY SWD THRU THE DAY AND MUCH OF THE AREA STAYS IN UPR LVL ANTI-CYCLONIC FLOW THRU THE AFTN. PLUS...THE NAM (AND THE GFS TO AN EXTENT) SUGGEST WEAKENING CONVERGENCE ALONG THE FRONT AS THE BEST UPR DYNAMICS LIFT N INTO MI. FINALLY...UNLESS THE FRONT SPEEDS UP...THE FRONTAL WILL GENERALLY PASS OVER THE AREA IN THE NIGHTTIME WHICH WOULD NOT BE FAVORABLE FOR INSTABILITY. HOWEVER...WITH ALL OF THIS SAID...I DO THINK THERE WILL BE AT LEAST SCT STORMS ALONG THE FRONT. PRECIPITABLE WATER VALUES POOL ALONG THE FRONT TO OVER 2.0 INCHES SO MOISTURE DOES INCREASE IMMEDIATELY AHD OF THE FRONT. I AM JUST UNSURE OF THE SEVERITY OF ANY STORM THAT DEVELOPS...AS THE KINEMATIC PROFILES WILL BE GENERALLY WK BUT THE THERMODYNAMIC PROFILE WL BE VERY FAVORABLE. SPC HAS PLACED MOST OF THE FORECAST AREA UNDER A SLIGHT RISK FOR THU. IF SVR WX DOES DEVELOP THU AFTN/EVENING...STRONG WINDS WL BE THE GREATEST RISK AS SFC DELTA THETA-E VALUES APPROACH 25C. WL THEREFORE GO WITH CHC POPS THU AFTN IN TOL AND LATE THU AFTN CLE AND FDY. AM A LITTLE CONCERNED THAT A FEW POP UP STORMS MAY DEVELOP THU AFTN OVER THE WEST AS INCREASED Q-VECT CONV AND THE RIGHT ENTRANCE REGION OF THE JET MOVES OVER THE WRN PART OF THE AREA. WL GO WITH 50 POPS ALL AREAS THRU NIGHT. DO THINK IT WILL DRY OUT RATHER QUICKLY LATE THU NIGHT INTO FRIDAY MRNG BEHIND THE FRONT AS HIGH PRES QUICKLY BUILDS INTO THE REGION. GFS SUGGESTS THAT THE FRONT WL HANG UP FURTHER N THAT THE NAM. THIS ALLOWS THE GFS TO KEEP CLDS AND EVEN SOME LIGHT QPF ACROSS THE FORECAST AREA INTO FRI EVENING. DO NOT BELIEVE THIS SOLN ATTM AS THE FRONT SHOULD HAVE ENOUGH MOMENTUM TO MAKE IT FAR ENOUGH SOUTH TO CLEAR OUT THE AREA BY FRI EVENING. SHOULD BE A QUIET SAT WITH HIGH PRES OVERHEAD...MOSTLY SUNNY SKIES AND NEAR OR MAYBE SLIGHTLY BELOW NORMAL TEMPS. 850MB TEMPS CONTINUE AROUND +20C ON THU...BUT SWLY SFC WINDS WILL BE STRONGER. THIS SHOULD ALLOW FOR TEMPS TO ONCE AGAIN RISE WELL INTO THE 90S WITH INCREASING HUMIDITY. EXPECT HEAT INDEX VALUES CLOSE TO 100. MUCH COOLER ON FRIDAY WITH TEMPS IN THE UPR 70S/LOWER 80S. && .LONG TERM (SUN THRU WED)... CONFIDENCE IN MEDIUM RANGE FCST NOT AS HIGH AS IT HAS BEEN LATELY. EXTENDED MDLS SUGGEST A MORE AMPLIFIED PATTERN SETTING UP ACROSS NORTH AMERICA. MDLS SUGGEST THAT A TROUGH WL DIG INTO THE NWRN STATES MON-WED...BUT THE AMPLITUDE AND TIMING OF THIS UPR TROUGH IS OF DEBATE. THE OP GFS AND UKMET SUGGEST THE SHORT WAVE DIGGING INTO THE PAC NW MON AND TUE WITH RISING HEIGHTS ACROSS THE REGION. ECMWF SUGGESTS A WEAKER TROUGH OVER THE PAC NW WITH LESS HEIGHT RISES ACROSS THE REGION. THERE IS SOME SUPPORT FOR THIS SOLN FROM SVRL GFS ENS MEMBERS...SO THIS CANNOT BE RULED OUT. IN FACT...WHEN LOOKING AT SPAGHETTI PLOTS FROM THE GFS ENS...THERE ARE SOME MEMBERS THAT ARE TOTALLY OUT OF PHASE IN THE MON/TUE TIME PERIOD. SO...WITH CONFIDENCE BEING A LITTLE LOWER THAN IT HAS BEEN LATELY...HAVE OPTED TO GO WITH A GENERAL ENSEMBLE MEAN FOR TEMPS...PERHAPS TRENDING A LITTLE HIGHER THAN THE ENSEMBLE MEAN. HIGHS GENERALLY IN THE MID 80S...LOWS IN THE MID-UPR 60S. GFS ALSO HAS PCPN EACH DAY MON-WED ACROSS OHIO. WITH THE MDL SHOWING A SFC RIDGE ACROSS THE AREA IT SEEMS HARD TO BELIEVE THAT THERE WILL BE MUCH PCPN. WL LEAVE IT DRY FOR NOW. MAY NEED SOME SMALL POPS AS THE TIME NEARS...BUT FOR NOW A DRY FCST SEEMS REASONABLE GIVEN THE PATTERN. && .AVIATION (18Z-18Z)... HIGH PRESSURE WILL REMAIN IN CONTROL NEXT 24 HOURS. EXPECT SOME MVFR VIS HZ/BR DEVELOPING OVERNIGHT...BUT DON'T THINK IT WILL QUITE AS BAD AS THIS MORNING SINCE GRADIENT WILL BE A LITTLE STRONGER SO DON'T EXPECT WINDS TO DECOUPLE. COLD FRONT ACROSS WISCONSIN INTO IOWA WILL BE PUSHING INTO CENTRAL LOWER MICHIGAN BY THIS TIME TOMORROW. EXPECT SOME SCATTERED TSRA DEVELOPMENT AHEAD OF FRONT APPROACHING NW OH BY THIS TIME TOMORROW. && .CLE WATCHES/WARNINGS/ADVISORIES... .OH...NONE. .PA...NONE. $$ SHORT TERM...MRD LONG TERM...MRD AVIATION...DJB oh AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE STATE COLLEGE PA 240 PM EDT WED AUG 3 2005 .SHORT TERM (TONIGHT THROUGH THURSDAY NIGHT)... TYPICAL MID SUMMER...HAZY...HOT AND INCREASINGLY HUMID WEATHER WILL CONTINUE THRU THURSDAY AS THE HIGH IN THE EAST REMAINS THE DOMINANT FEATURE AND SLOWLY SLIPS EASTWARD OFF THE COAST. DEWPOINTS TODAY IN THE MID TO UPPER 60S WILL SLOWLY PUMP UP AS THE HIGH MOVES EAST AND ALLOWS A BROAD SW FLOW TO INCREASE ACROSS THE REGION. FOR REMAINDER OF TODAY...STILL THINK ONLY WIDELY SCATTERED TO ISOLATED CONVECTION TO DEAL WITH...LESS THAN 20% COVERAGE. ANY STORMS THAT DO MANAGE TO PUNCH THRU THE CAP HAVE THE POTENTIAL TO BE RATHER POTENT AS WE HAVE...ACCORDING TO THE RUC AND HIGH RES ETA...SOMETHING ON THE ORDER OF 2500-3500J OF CAPE TO PLAY WITH. WEAK WIND FIELDS SUGGEST WE WOULD BE DEALING WITH PULSE VARIETY STORMS...AS WE HAVE HAD EACH OF THE LAST 2 EVENINGS. WITH THE AMOUNT OF MID LEVEL DRY AIR INDICATED IN THE FCST SOUNDINGS...INVERTED V TYPE...A DAMAGING DOWNBURST WOULD BE THE MAIN THREAT...THOUGH WE HAVE HAD A COUPLE OF REPORTS ON RECENT DAYS OF PENNY SIZE HAIL. ANY POSSIBLE ACTIVITY SHUD FADE WITH LOSS OF HEATING BY 8-10 PM...LEAVING ANOTHER TRANQUIL MILD NIGHT. THINK THU WILL BE A CARBON COPY OF TODAY...ONLY A BIT MORE HUMID. && .LONG TERM (FRIDAY THROUGH WEDNESDAY)... LIKE YESTERDAY...SOME CELLS POPPING UP ABOUT THE SAME TIME AND LOCATION. STILL RATHER COOL AT 500 MB...MINUS 10. LI MINUS 5 TO MINUS 7...ESTIMATED VIL MID TO UPPER 50S. ANYWAY...NOT MUCH CHANGE FOR THU...MORE SW FLOW...BUT THERE COULD BE A LITTLE ACTION. MAIN ACTION IS LATE THU NIGHT ACROSS N AND W PA...INTO FRIDAY EVENING...AS FRONT DROPS SE. MODELS NOW FASTER WITH IT. DID CUT POPS OUT FOR SATURDAY...EXCEPT FAR SE...TO FIT WITH PHI...AND MODELS HINT AT WEAK LOW OVER EASTERN PA. KEPT POPS OUT FOR SATURDAY NIGHT. COOL AIR NOT REAL DEEP. DID END UP KEEPING MENTION OF SHOWERS AND STORMS IN FOR SUNDAY...AFTER LOOKING AT NEW MODELS AND HPC GRIDS. LIKEWISE...DID ADD SOME LOW POPS IN FOR MONDAY...AND WED. WEAK SYSTEM MOVES ACROSS MONDAY...AND LEE SIDE TROUGH DEVELOPS ON WED. OTHERWISE...FEW CHANGES TO FCST...KEPT MOST PERIODS DRY. HARD TO SEE ANY BIG COOL DOWN ANYTIME SOON. && .AVIATION... LITTLE IN THE WAY OF HAZE RESTRICTING VIZ THIS AFTERNOON SO ALL TERMINALS ARE VFR. OVERNIGHT WILL PROBABLY SEE THE NORMAL DIURNAL FADE AWAY OF VISIBILITY IN THIN FOG AND HAZE WITH IT TAKING A FEW HOURS IN THE MORNING TO MIX OUT THE LOW LEVEL MOISTURE. AM THINKING MAINLY SOME MVFR VIZ PROBLEMS TO DEVELOP...BUT COULD BE WORSE IN THE RIVER VALLEYS AT PLACES LIKE IPT AND SEG. CHANCE OF CONVECTION WILL BE PRETTY LOW...BUT NOT TOTALLY OUT OF THE QUESTION. WE REMAIN PRETTY WELL CAPPED BUT WITH HIGH HEAT AND INCREASING HUMIDITY...A FEW POP UP STORMS CANNOT BE RULED OUT IN THE AFTERNOON THRU EVENING HOURS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...LACORTE LONG TERM...MARTIN AVIATION...LACORTE pa AREA FORECAST DISCUSSION...UPDATED NATIONAL WEATHER SERVICE SAN ANGELO TX 1120 AM CDT WED AUG 3 2005 .UPDATE... LATEST VISIBLE SATELLITE IMAGERY INDICATE CUMULUS FIELD BEGINNING TO DEVELOP ACROSS OUR SOUTHEASTERN COUNTIES. AT THE SURFACE...DEWPOINTS ACROSS WEST CENTRAL TEXAS RANGE FROM AROUND 70 EAST TO THE UPPER 60S SOUTH AND THE MID 60S NORTH. RUC INDICATES INSTABILITY SPREADING ACROSS THE SOUTHEASTERN HALF OF OUR CWFA FOR THE NEXT SEVERAL HOURS. WITH THE POTENTIAL FOR SHOWERS AND A FEW THUNDERSTORMS DEVELOPING ACROSS THIS AREA...DECIDED TO INCREASE POPS TO 20S FOR OUR SOUTHEASTERN HALF FOR THE REST OF TODAY. ALSO...EXTENDED THIS AREA FOR A FEW HOURS INTO THIS EVENING. OTHERWISE...NO OTHER CHANGES. && .PREV DISCUSSION... (ISSUED 216 AM CDT WED AUG 3 2005) SHORT TERM...THIS MORNING...WHAT IS LEFT OF THE TUTT LOW IS SHEARING OUT OVER SOUTH CENTRAL TEXAS. THE NAM WANTS TO HOLD ITS IDENTITY A LITTLE MORE THROUGH THE DAY THAN THE GFS AND AS A RESULT IS A LITTLE MORE WET. NAM HAS THE PAST COUPLE OF DAYS BEEN A LITTLE TO WET WITH THIS SYSTEM AND WILL TREND MORE TOWARDS THE GFS SOLUTION. HOWEVER WE WILL BE ON THE EASTERN SIDE OF WHAT IS LEFT OF THE AFOREMENTIONED FEATURE...AND AS A RESULT WILL CONTINUE TO SEE ISOLATED TO WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WITH AFTERNOON HEATING WITH THE BEST CHANCES ACROSS OUR SOUTHEASTERN ZONES. STILL NOT MUCH CHANGE FROM THINKING YESTERDAY AS ANOTHER WEAK LOW IS FORECAST TO MOVE INTO THE SAME GENERAL AREA AS THE CURRENT ONE THURSDAY AFTERNOON. SO STILL SOME POTENTIAL FOR WIDELY SCATTERED ACTIVITY MAINLY ACROSS THE EASTERN COUNTIES. SHOULD ALSO SEE AN OVERALL INCREASE IN CLOUDS AND AS A RESULT TEMPERATURES SHOULD BE SOMEWHAT COOLER THURSDAY. COLD FRONT SHOULD BEGIN TO REACH THE NORTHWESTERN COUNTIES BY LATE THURSDAY NIGHT AND IS A ADDITION WITH THE SECOND TUTT SHOULD SEE COVERAGE OF PRECIPITATION BEGIN TO INCREASE THURSDAY NIGHT...AND AS A RESULT INCREASED POPS FOR THAT TIME. LONG TERM...MADE SOME CHANGES IN THE FRIDAY THROUGH TUESDAY TIME FRAME AS RECENT TRENDS WITH THE FRONT AND MORE WIDESPREAD PRECIPITATION CONTINUE TO TREND TOWARDS A COOLER AND MORE WET SOLUTION. THE OPERATIONAL GFS IS ON THE COOLER SIDE OF GUIDANCE THROUGH SUNDAY AND WILL PRETTY GO WITH THAT WITH THE EXCEPTION OF FRIDAY WHERE WE PLAN TO SHAVE OFF A FEW DEGREES. ALSO INCREASED POPS UP TO CHANCE CATEGORY FOR MUCH OF THE AREA IN THE FRIDAY THROUGH SATURDAY TIME FRAME WITH THE FRONT IN THE AREA. MAY ALSO SEE SOME ACTIVITY LINGER THROUGH MONDAY/TUESDAY AND INSERTED SOME SLIGHT CHANCE POPS. ALSO WENT ON THE LOWER SIDE OF GUIDANCE FOR THE MONDAY THROUGH TUESDAY IN ANTICIPATION OF MORE CLOUDS AND POSSIBILITY OF SOME LINGERING SHOWER ACTIVITY. && .SJT WATCHES/WARNINGS/ADVISORIES... TX...NONE. && $$ 23/HUBER tx