Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 08/07/14


AREA FORECAST DISCUSSION
NWS TUCSON AZ
305 PM MST TUE AUG 5 2014 .SYNOPSIS...DRIER AIR WILL LIMIT THUNDERSTORMS TO MAINLY NEAR THE NEW MEXICO BORDER THROUGH THURSDAY. DEEPER MOISTURE WILL THEN RETURN FRIDAY AND CONTINUE INTO EARLY NEXT WEEK. THIS WILL PROVIDE A RETURN OF ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS. DAYTIME TEMPERATURES THIS WEEK WILL BE NEAR OR SLIGHTLY ABOVE NORMAL. && .DISCUSSION...ISOLATED THUNDERSTORMS OVER FAR NERN SONORA WITH PRECIP-FREE CONDITIONS ACROSS SE AZ AT THIS TIME. VISIBLE SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATED MOSTLY CLEAR SKIES TO PARTLY CLOUDY SKIES...WITH THE BULK OF CUMULOFORM CLOUDS ACROSS ERN SECTIONS. HAVE MAINTAINED ISOLATED SHOWERS/TSTMS NEAR THE NEW MEXICO INTO EARLY THIS EVENING AS PER THE 05/20Z RUC HRRR SOLUTION. CLOUDS SHOULD THEN DISSIPATE AROUND OR SHORTLY AFTER SUNSET FOLLOWED BY CLEAR SKIES OR MOSTLY CLEAR SKIES LATER TONIGHT. DRY GENERALLY WLY FLOW ALOFT TO PREVAIL WED-THUR AS HIGH PRESSURE REMAINS CENTERED OVER NRN CHIHUAHUA AND A WEAK UPPER LEVEL TROUGH CONTINUES OVER THE GREAT BASIN REGION. VARIOUS 05/12Z NWP MODELS INDICATE THE POTENTIAL FOR LESS SHOWER/TSTM ACTIVITY WED VERSUS THIS AFTERNOON. ALTHOUGH INHERITED POPS WERE REDUCED SOMEWHAT...FOR NOW HAVE MAINTAINED ISOLATED COVERAGE OF SHOWERS/TSTMS MAINLY NEAR THE NEW MEXICO BORDER WED AFTERNOON/EVENING. SLIGHTLY GREATER COVERAGE OF SHOWERS/TSTMS SHOULD OCCUR THUR...WITH ISOLATED SHOWERS/TSTMS SHOULD GENERALLY OCCUR SE OF A HANNAGAN MEADOW-SAFFORD-SIERRA VISTA LINE. THEREAFTER...THERE WERE DIFFERENCES BETWEEN THE 05/12Z NAM/GFS/ECMWF REGARDING THE TIMING FOR DEEPER MOISTURE AND GREATER COVERAGE OF SHOWERS/TSTMS WILL RETURN TO SE AZ. IN ESSENCE...THE NAM FAVORED FRI AS A POTENTIAL SIGNIFICANT INCREASE IN COVERAGE OF SHOWERS/TSTMS...THE ECMWF FAVORED SAT...AND THIS VERSION OF THE GFS DELAYED THE ONSET OF MORE SUBSTANTIAL CONVECTIVE ACTIVITY UNTIL SUN. THE OFFICIAL FORECAST DEPICTS A GRADUAL DAILY INCREASE IN SHOWERS/ TSTMS FRI-SUN. THUS...SCATTERED MAINLY AFTERNOON/EVENING SHOWERS/TSTMS SHOULD RETURN TO THE AREA BY SUN. A FAIRLY DEEP GENERALLY SELY FLOW REGIME IS PROGGED TO OCCUR MON-TUE IN RESPONSE TO HIGH PRESSURE ALOFT CENTERED OVER NRN NEW MEXICO. THIS PATTERN IS EXPECTED TO YIELD THE DAILY CYCLE OF SCATTERED MAINLY AFTERNOON/EVENING SHOWERS/ TSTMS. ENOUGH MOISTURE APPEARS TO EXIST TO SUPPORT AT LEAST A SLIGHT CHANCE OF SHOWERS/TSTMS DURING THE OVERNIGHT/EARLY MORNING HOURS MON-TUE. HIGH TEMPS WED WILL BE NEARLY IDENTICAL TO TEMPS ACHIEVED THIS AFTERNOON. A VERY GRADUAL DAILY COOLING TREND WILL THEN OCCUR THUR- SAT FOLLOWED BY NO SIGNIFICANT CHANGE IN DAYTIME TEMPS SUN-TUE. && .AVIATION...VALID THRU 7/00Z. ISOLATED -TSRA/-SHRA NEAR THE FAR SE AZ/FAR SW NEW MEXICO BORDER EAST OF KDUG ENDING AROUND 06/03Z. ISOLATED -TSRA/-SHRA MAINLY NEAR THE NEW MEXICO BORDER AGAIN WEDNESDAY AFTERNOON. OTHERWISE...CLEAR SKIES WEST OF KTUS THRU WEDNESDAY AFTERNOON. KTUS VICINITY EASTWARD EXPECT A FEW-SCT CLOUDS WITH BASES GENERALLY AT 8-12K FT AGL EARLY THIS EVENING AND WEDNESDAY AFTERNOON. CLEAR SKIES OR MOSTLY CLEAR SKIES EAST OF KTUS LATE TONIGHT AND WEDNESDAY MORNING. SURFACE WINDS WILL BE MAINLY LESS THAN 10 KTS ALTHOUGH A FEW GUSTS TO AROUND 20 KTS MAY OCCUR WEDNESDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS WILL PREVAIL THROUGH THURSDAY EXCEPT FOR A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS NEAR THE NEW MEXICO BORDER. EXPECT ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS TO RETURN ON FRIDAY AND CONTINUE INTO EARLY NEXT WEEK AS DEEPER MOISTURE RETURNS TO THE AREA. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON FRANCIS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
925 AM MST TUE AUG 5 2014 .SYNOPSIS...DRIER AIR WILL LIMIT THUNDERSTORMS TO MAINLY NEAR THE NEW MEXICO BORDER THROUGH MIDWEEK. DEEPER MOISTURE WILL THEN RETURN FRIDAY AND CONTINUE INTO EARLY NEXT WEEK. THIS WILL PROVIDE A RETURN OF ISOLATED TO SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS. DAYTIME TEMPERATURES THIS WEEK WILL BE NEAR OR SLIGHTLY ABOVE NORMAL. && .DISCUSSION...CLEAR SKIES PREVAIL ACROSS SE AZ AT THIS TIME EXCEPT FOR A FEW CUMULOFORM CLOUDS ACROSS THE WHITE MOUNTAINS AND THE CHIRICAHUA MOUNTAINS IN ERN COCHISE COUNTY. DEWPOINTS AT LOWER ELEVATIONS VALID 16Z RANGED FROM THE UPPER 40S-LOWER 60S F. THESE TEMPS WERE GENERALLY 5-15 DEGS F LOWER VERSUS 24 HOURS AGO. SURFACE TEMPS VALID 16Z WERE VIRTUALLY UNCHANGED VERSUS THIS TIME MON. 05/12Z KTWC SOUNDING TOTAL PRECIP WATER WAS 0.78 INCH...AND THIS VALUE WAS NEARLY 2 STANDARD DEVIATIONS BELOW NORMAL. 05/12Z UPPER AIR PLOTS INDICATED 592 DM HIGH PRESSURE CENTERED OVER WEST CENTRAL TEXAS AND A WEAK TROUGH WAS OVER THE GREAT BASIN. LIGHT GENERALLY WLY FLOW PREVAILED OVER SE AZ. 05/12Z UNIV OF AZ WRF-NAM AND 05/14Z RUC HRRR WERE SIMILAR WITH DEPICTING A FEW PRECIP ECHOES TO OCCUR THIS AFTERNOON NEAR THE NEW MEXICO BORDER. MORE SPECIFICALLY...THE FAVORED AREAS FOR ISOLATED SHOWERS/TSTMS TO OCCUR APPEARS TO BE ACROSS THE WHITE MOUNTAINS AND THE CHIRICAHUA MOUNTAINS IN ERN COCHISE COUNTY. BELIEVE ANY SHOWERS/ TSTMS THAT DO OCCUR WILL DISSIPATE AROUND OR SHORTLY AFTER SUNSET. GIVEN THE VERY DRY REGIME...ANY PRECIP AMOUNTS WILL BE QUITE LIGHT. CLEAR SKIES OR MOSTLY CLEAR SKIES WILL PREVAIL LATER TONIGHT. WILL MAKE SOME MINOR ADJUSTMENTS TO THE GRIDDED DATA POP/WEATHER FIELDS TO REFLECT THE ABOVE SCENARIO. OTHERWISE...PLEASE REFER TO THE ADDITIONAL SECTIONS FOR FURTHER DETAIL. && .AVIATION...VALID THRU 6/18Z. ISOLATED -TSRA/-SHRA MAY OCCUR NEAR THE NEW MEXICO BORDER...AND ESPECIALLY ACROSS THE WHITE MOUNTAINS NE OF KSAD THIS AFTERNOON AND EARLY THIS EVENING. OTHERWISE...EXPECT A FEW TO SCATTERED CUMULUS CLOUDS WITH BASES GENERALLY AT 8-12K FT AGL THIS AFTERNOON AND EARLY THIS EVENING. CLEAR SKIES WEST OF KTUS TONIGHT WITH A FEW TO SCATTERED CLOUDS ABOVE 10K FT AGL EAST OF KTUS. SURFACE WINDS WILL BE MAINLY LESS THAN 10 KTS ALTHOUGH A FEW GUSTS TO AROUND 20 KTS MAY OCCUR THIS AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS WILL PREVAIL THROUGH THURSDAY EXCEPT FOR A SLIGHT CHANCE OF AFTERNOON THUNDERSTORMS NEAR THE NEW MEXICO BORDER. INCREASING MOISTURE STARTING FRIDAY AND CONTINUING INTO EARLY NEXT WEEK WILL PROVIDE A RETURN OF ISOLATED TO SCATTERED THUNDERSTORMS. THE BEST CHANCES FOR RAINFALL WILL BE DURING THE AFTERNOON AND EVENING HOURS. && .PREV DISCUSSION.../ISSUED AT 214 AM MST/...BY THURSDAY THE MODELS INDICATE THAT HIGH PRESSURE WILL BE OVER NORTHEAST MEXICO AND NORTHWARD INTO NEW MEXICO...WITH A TROUGH OVER THE GREAT BASIN AND INTO SOUTH CENTRAL CALIFORNIA. THIS WILL RESULT IN MORE SOUTHERLY WINDS ACROSS THE REGION THAT WILL TAP INTO SOME OF THE HIGHER MOISTURE TO OUR SOUTH...RESULTING IN A MODEST INCREASE IN RAIN CHANCES...MAINLY FROM TUCSON SOUTH AND EASTWARD. BY LATE THIS WEEK AND INTO THE WEEKEND...THE HIGH SHIFTS TO THE NORTH AND EAST EXTENDING FROM SOUTHERN TEXAS INTO NORTHERN NEW MEXICO WITH MORE OF A SOUTHEASTERLY FETCH. IN ADDITION... DISTURBANCES MOVING WESTWARD UNDER THE HIGH WILL HELP TO ENHANCE ACTIVITY. SO...MADE ONLY MINOR ADJUSTMENTS TO THE POP FORECAST IN THE EXTENDED FORECAST...WITH BASICALLY SCATTERED TYPE POPS IN THE FORECAST FOR MOST AREAS. HIGH TEMPERATURES WILL GENERALLY BE 3 TO 5 DEGS ABOVE NORMAL TODAY THROUGH THURSDAY...THEN NEAR NORMAL FOR FRIDAY THROUGH THE WEEKEND AND BACK TO AROUND 2 TO 4 DEGS ABOVE NORMAL FOR MONDAY. LOW TEMPS WILL BE NEAR OR SLIGHTLY ABOVE NORMAL WEDNESDAY THROUGH SATURDAY MORNINGS...THEN 2 TO 3 DEGS ABOVE NORMAL SUNDAY AND MONDAY. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON FRANCIS PREVIOUS DISCUSSION...MOLLERE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
939 PM MDT WED AUG 6 2014 .UPDATE... ISSUED AT 933 PM MDT WED AUG 6 2014 NO MAJOR CHANGES TO THE GOING FORECAST. REMOVED POPS FOR THE REST OF THE NIGHT...WITH THE EXCEPTION OF EXTREME NORTHERN EL PASO COUNTY. RADAR INDICATES A WEAK ROUGE CELL NEAR MONUMENT HILL TRACKING EAST...AND MAY CLIP THE COUNTY BOUNDARY THROUGH 11 PM. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 317 PM MDT WED AUG 6 2014 CURRENTLY... WEAK BOUNDARY WAS MOVING SOUTH ACROSS THE EASTERN PLAINS. THIS BOUNDARY WAS INITIATING SOME CONVECTION OVER KIOWA COUNTY AT 2 PM. GENERALLY N OF HIGHWAY 50 WINDS WERE FROM A WEAK NORTHERLY COMPONENT WHILE WINDS WERE GENERALLY LIGHT AND VARIABLE SOUTH OF 50. OVER THE MTNS...ESPECIALLY INTERIOR MTNS...IT HAS DRIED OUT QUITE A BIT WITH DWPTS IN THE 30S...WITH A FEW 20S AT HIGHER ELEVATIONS. IT ALSO APPEARS TO BE DRIER ALOFT AS CLOUDS ARE NOTICEABLY MUCH LESS ONCE YOU GET SOUTH OF US-50. REST OF TODAY INTO TONIGHT... MAIN CONCERN IN THE IMMEDIATE SHORT TERM WILL BE THE WALDO BURN SCAR. HRRR SHOWING BEST CHANCE OF PRECIP THIS AFTERNOON MAINLY OVER C MTNS...GREATER PIKES PEAK REGION AND KIOWA COUNTY. HAVE ALREADY INCREASED POPS THIS AREA IN EARLIER UPDATES. ALTHOUGH FLASH FLOODING NOT LIKELY OVER BURN SCARS...ONE HEAVY SHOWER IN THE WRONG PLACE CAN EASILY CAUSE PROBLEMS. FOR LATER TONIGHT...LOW LVL MOISTURE WILL LIKELY INCREASE...ESPECIALLY OVER THE FAR E PLAINS AS 60 DWPTS CURRENTLY IN SW NEB ARE SHUNTED SOUTHWARD BEHIND THE FRONT. WE WILL LIKELY SEE SOME LOW CLOUDS TOMORROW MORNING...ESPECIALLY OVER THE FAR SE PLAINS IN THE GREATER KIOWA COUNTY REGION. NAM GUIDANCE HAS SOME PRECIP LATE TONIGHT THIS REGION BUT IT IS LIKELY A BIT OVERDONE. WITH DRIER AIR OVER THE MTNS...WILL LIKELY SEE ANOTHER COOL NIGHT OVER THE HIGHER TRRN...ESPECIALLY ALONG THE CONTDVD AND HIGH VALLEYS. TOMORROW... EXPECT MORE CONVECTION OVER THE AREA TOMORROW AND HAVE POPS DRAWN UP EVERYWHERE OVER THE CWA BY TOMORROW AFTERNOON. PWAT VALUES INCREASE TO OVER AN INCH OVER THE PLAINS AND AREA WILL LIKELY BE FEELING THE LEADING EDGE OF A WELL DEFINED TROUGH OVER E UTAH. CONVECTION SHOULD INITIATE AROUND ITS NORMAL TIME OVER THE MTNS (NOONISH) AND THEN INCREASE AND MOVE EAST OVER THE PLAINS. BEST CHANCE OF POPS WILL BE OVER C MTNS...PIKES PEAK AREA AND FAR E PLAINS...ESPECIALLY BY LATE AFTERNOON. FLOODING THREAT ON THE BURN SCARS WILL BE HIGHER TOMORROW THAN TODAY. STORMS MAY BE A BIT MORE ORGANIZED TOMORROW DUE TO A BIT BETTER DEEP SHEAR AND HIGHER CAPE VALUES. AN ISOLD SVR STORM CANT BE RULED OUT. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 317 PM MDT WED AUG 6 2014 .THURSDAY EVENING AND FRIDAY...MAIN CHALLENGE WILL BE THE MOVEMENT OF THE MCS WHICH DEVELOPS OVER NORTHEAST COLORADO...AND THE AMOUNT OF MOISTURE AND INSTABILITY FROM THE OUTFLOW. OVER NORTHEAST COLORADO MOST MODELS DEVELOP CONVECTION THURSDAY AFTERNOON AND EVENING...WHICH MOVES TO THE EAST OR EAST SOUTHEAST DURING THE EVENING. BELIEVE MOST OF THE CONVECTION WILL STAY TO THE NORTH OF THE CWA...BUT THERE IS THREAT FOR SOME OF THE CONVECTION TO DEVELOP OVER THE PALMER DIVIDE REGION AND MOVE TO THE SOUTHEAST DURING THURSDAY EVENING. POPS GRIDS KEEP SCATTERED POPS OVER THESE REGIONS FOR THURSDAY EVENING AND INTO THE OVERNIGHT. ON FRIDAY...EXPECT OUTFLOW FROM THE MCS TO INCREASE LOW LEVEL MOISTURE OVER THE EASTERN PLAINS AND INTERSTATE 25 CORRIDOR. CANNOT GET VERY SPECIFIC ABOUT AMOUNT OF MOISTURE AND INSTABILITY IN THE OUTFLOW FROM MCS...BUT HUNCH IS OUTFLOW WILL BE STRONGER THAN MOST MODELS SUGGEST. IF THIS IS THE CASE...LOW LEVELS COULD BECOME MORE UNSTABLE DUE TO INCREASED MOISTURE. HOWEVER...IF THE LOW LEVELS ARE TOO CLOUDY OR COOL...ATMOSPHERE MAY BE STABLE ON THE PLAINS. DECIDED TO GO WITH SCATTERED POPS MAINLY ALONG PALMER DIVIDE AND PORTIONS OF THE EASTERN PLAINS ON FRIDAY. NAM12 HAS A POTENT AND COMPACT SHORTWAVE MOVING OVER EASTERN COLORADO FRIDAY...AND CAPES OVER PORTIONS OF THE SOUTHEAST PLAINS ARE OVER 2000 J/KG. THINK THIS MAY BE OVERDONE...BUT HIGHLIGHTS POTENTIAL FOR STRONGER CONVECTION FRIDAY. FURTHER WEST...MONSOON PLUME IS MOSTLY SUPPRESSED TO THE SOUTH...WITH ISOLATED TO SCATTERED POPS OVER THE MOUNTAINS. .SATURDAY AND SUNDAY...UPPER TROUGH REMAINS NEAR THE WEST COAST WITH THE AXIS OF THE 500 MB RIDGE OVER COLORADO. SOUTH TO SOUTHWEST FLOW ALOFT WILL START BRINGING MORE MIDDLE AND UPPER LEVEL MOISTURE INTO THE REGION. POPS INCREASE OVER THE MOUNTAINS ESPECIALLY ON SUNDAY. WEAK UPSLOPE FLOW COULD CONTINUE WITH LOW LEVEL MOISTURE REMAINING OVER THE PLAINS. .MONDAY THROUGH WEDNESDAY...GFS AND EC SUGGEST THE BEGINNING OF A PATTERN CHANGE WHICH WILL RESULT IN THE UPPER RIDGE RETROGRADING AND NORTHWEST FLOW DEVELOPING OVER THE REGION. MORE SUBTLE FEATURES WILL AFFECT THE DAY TO DAY WEATHER. CURRENT INDICATIONS ARE A DECREASE IN MID LEVEL MOISTURE BY MID WEEK FOR A DECREASED CHANCE OF DIURNAL CONVECTION OVER THE MOUNTAINS. ABUNDANT LOWER LEVEL MOISTURE ON THE PLAINS WILL GRADUALLY MOVE EAST OF THE STATE. LIKELY STILL ENOUGH MOISTURE FOR DIURNAL CONVECTION...BUT PATTERN CHANGES SUGGESTS LOWER COVERAGE WITH LESS INTENSITY. --PGW-- && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 317 PM MDT WED AUG 6 2014 ISOLD TSRA WILL BE POSSIBLE LATE THIS AFTERNOON AND EARLY EVENING OVER KCOS...WITH A BETTER CHANCE OF TSRA TOMORROW AFTERNOON. OTHERWISE...VFR EXPECTED. FOR KPUB AND KALS...VFR NEXT 24. THERE WILL BE A SLIGHT CHANCE OF TSRA OVER THESE TWO SITES TOMORROW AFTERNOON. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...HODANISH LONG TERM...PGW AVIATION...HODANISH
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
330 PM MDT TUE AUG 5 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 328 PM MDT TUE AUG 5 2014 NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE MOUNTAINS ARE PUSHING NORTHEAST. SOME CELLS HAVE BEEN PRODUCING BETWEEN A THIRD TO A HALF OF AN INCH OF RAIN IN ABOUT 15-30 MINUTES...WITH STRONGER CELLS PRODUCING OVER THREE-QUARTERS OF AN INCH. A CURRENT PW VALUES HOVERING ABOUT AN INCH RIGHT NOW AND ARE EXPECTED TO START LOWERING AS DRIER AIR...EVIDENT ON WATER VAPOR SATELLITE...MOVES IN FROM THE SOUTHWEST. DEWPOINTS IN THE UPPER 40S OVER THE MOUNTAINS WILL BE PUSHING EAST WHERE DEWPOINTS OVER THE EASTERN PLAINS ARE IN THE UPPER 50S TO LOWER 60S. MOVEMENT ON THESE STORMS ARE AROUND 15 KTS...SO FLOOD THREAT AT THIS POINT IS THERE IN SOME SPOTS...BUT OVERALL AREA WIDE IS LOW. TRAINING STORMS COULD CREATE A PROBLEM. BIGGEST AREA OF CONCERN IS DOWN SOUTH ALONG THE PALMER DIVIDE AREA AND SOUTHERN FOOTHILLS WITH ANOTHER THREAT UP OVER LARIMER COUNTY AS CONVECTION IS FORMING A TRAINING LINE. GUSTY OUTFLOW WINDS FROM THESE STORMS TONIGHT WILL ALSO BE ANOTHER THREAT...ESPECIALLY AS THE DRIER AIR ALOFT MOVES IN. THERE IS SLIGHTLY MORE INSTABILITY OUT EAST TOWARDS THE NEBRASKA BORDER...WHERE STORMS OUT HERE MAY BE ABLE TO STRENGTHEN ENOUGH FOR SMALL HAIL...OTHERWISE THE SEVERE STRENGTH STORM THREAT IS LOW. AS THE SHORTWAVE CONTINUES TO PUSH EAST...QG VERTICAL VELOCITY WILL SWITCH FROM LIGHT UPWARD TO LIGHT DOWNWARD. THIS COMBINED WITH THE LOSS OF DAYTIME HEATING WILL ALLOW CONVECTION TO DECREASE THIS EVENING AND SHOULD BE DIMINISHED BEFORE MIDNIGHT. THERE ARE HINTS FROM THE HIRES RAP MODEL THAT OUTFLOW FROM STORMS IN CENTRAL NEBRASKA MAY PUSH BACK INTO COLORADO TONIGHT TO KEEP CONVECTION GOING....AT THIS POINT DO NOT THINK THIS WILL HAPPEN WITH CURRENT STRENGTH AND MOTION OF THE STORMS OUT THERE. UPPER RIDGING WILL MOVE OVERHEAD TOMORROW WITH DRIER PW VALUES EXPECTED. A WEAK COOL FRONT WILL SLIDE SOUTH IN THE EARLY AFTERNOON TO KEEP MOST OF THE PLAINS STABLE FOR MUCH OF THE DAY. WITH MORE SUNLIGHT EXPECTED TOMORROW HOWEVER WILL LEAD TO NEARLY THE SAME OR SLIGHTLY WARMER TEMPERATURES COMPARED TO TODAY. LESS CONVECTION IS EXPECTED OVER THE MOUNTAINS...BUT WILL STILL LIKELY SEE ISOLATED TO SCATTERED ACTIVITY. ONCE THE FRONT PUSHES IN AND SOME UPSLOPE FLOW ESTABLISHES ITSELF...THERE MAY BE ENOUGH PUSH FOR SOME ISOLATED ACTIVITY ALONG THE NORTHERN FOOTHILLS AND ADJACENT PLAINS. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 328 PM MDT TUE AUG 5 2014 SOME THUNDERSTORMS POSSIBLE ACROSS THE AREA WEDNESDAY EVENING... MAINLY OVER THE FAR NORTHEAST PLAINS AS TAIL END OF MID LEVEL SHORTWAVE MOVES ACROSS NORTHEAST COLORADO. STORMS COULD PRODUCE BRIEF HEAVY RAIN FAR EASTERN PLAINS. THE ACTIVITY SHOULD END AROUND MIDNIGHT AS SUBSIDENCE BEHIND THE PASSING WAVE MOVES OVER THE AREA. BOUNDARY LAYER WIND AND RH PROGS SUGGEST THE POTENTIAL FOR LOW CLOUDS ACROSS MUCH OF THE PLAINS...MAINLY EAST OF A GREELEY TO DENVER LINE OVERNIGHT. AT THIS TIME...THE THREAT FOR ANY FOG APPEARS LOW AND WILL LEAVE OUT OF THE GRIDS. ON THURSDAY... THE UPPER RIDGE OVER COLORADO IS EXPECTED TO FLATTEN A BIT AS A SHORTWAVE MOVES ACROSS WYOMING. CENTER OF THE HIGH TO MOVE TOWARDS THE TEXAS AND OKLAHOMA PANHANDLES. EASTERLY LOW LEVEL FLOW ACROSS PLAINS TO PROVIDE UPSLOPE IN AND NEAR THE FOOTHILLS. IN ADDITION... TAIL END OF THE WAVE LOOKS TO CLIP THE NORTHEAST CORNER. THUS... SHOULD SEE SOME STORMS DEVELOP DURING THE AFTERNOON WHICH WILL CONTINUE INTO THE EVENING. BEST CHANCE FOR STORMS TO BE NORTHEAST OF GREELEY AND DENVER WHERE THE BETTER LOW LEVEL MOISTURE WILL BE LOCATED. BRIEF HEAVY RAIN POSSIBLE WITH SOME OF THE STORMS OVER THE FAR NORTHEAST CORNER. TEMPERATURES LOOK TO BE AROUND AVERAGE MOST AREAS. LATEST MODELS SHOWING THE DEVELOPMENT OF SOME SORT OF MCS OVER THE FAR EASTERN PLAINS LATE IN THE EVENING...PUSHING INTO KANSAS OVERNIGHT. SOME LINGERING STORMS POSSIBLE OVER THE FAR EASTERN PLAINS BEFORE THIS SYSTEM MOVES AWAY FROM THE AREA. FOR FRIDAY...THERE MAY BE A PUSH OF LOW LEVEL MOISTURE BACK ACROSS THE PLAINS EARLY IN THE MORNING WITH THE POTENTIAL FOR THE DEVELOPMENT OF LOW CLOUDS AGAIN. OTHERWISE... MODELS INDICATE ANOTHER WEAK MID LEVEL SHORTWAVE CLIPPING THE FAR NORTHEAST CORNER DURING THE AFTERNOON WHICH COULD GENERATE ANOTHER ROUND OF AFTERNOON AND EVENING THUNDERSTORMS. SOME STORMS POSSIBLE FURTHER WEST... MAINLY ALONG THE FOOTHILLS WHERE LOW LEVEL SOUTHEAST FLOW WILL BE IN PLACE. A FEW STORMS COULD LINGER AFTER MIDNIGHT ACROSS THE FAR PLAINS. ON SATURDAY...MODELS SHOW ELONGATED UPPER HIGH OVER COLORADO WITH THE CENTER OVER NORTHEAST TEXAS. APPEARS A BATCH OF MONSOONAL MOISTURE LOOKS TO MOVE ACROSS THE AREA DURING THE AFTERNOON AND EVENING. THIS MAY RESULT IN A BETTER CHANCE FOR THUNDERSTORMS MOST LOCATIONS. TEMPERATURES BOTH FRIDAY AND SATURDAY TO HOVER AROUND AVERAGE. FOR THE LATER DAYS...SUNDAY THROUGH TUESDAY. UPPER LEVEL RIDGE TO REMAIN OVER COLORADO THROUGH THE PERIOD. THERE APPEARS TO BE SOME DECREASE IN THE MONSOONAL MOISTURE THOUGH ENOUGH FOR SOME CHANCE OF AFTERNOON AND EVENING THUNDERSTORMS. BEST CHANCE TO BE ACROSS THE MOUNTAINS. BY TUESDAY...BOTH ECMWF AND GFS SHOW THE UPPER RIDGE FLATTENING AS A SHORTWAVE MOVES ACROSS WYOMING. FLOW ALOFT TO BECOME MORE WESTERLY...WITH MOST OF THE MONSOONAL MOISTURE BEING SHUNTED SOUTH OF THE AREA. WILL KEEP A SLIGHT CHANCE OF STORMS GOING MOST LOCATIONS. TEMPERATURES LOOK TO NEAR OR SLIGHTLY BELOW AVERAGE. && .AVIATION...(FOR THE TAFS THROUGH 00Z WEDNESDAY LATE AFTERNOON) ISSUED AT 328 PM MDT TUE AUG 5 2014 VFR CONDITIONS EXPECTED FOR THE NEXT 36 HOURS. CONVECTION OVER THE FOOTHILLS AND PALMER DIVIDE WILL CONTINUE MOVING EAST- NORTHEAST OVER THE PLAINS WITH TSTORMS AFFECTING THE AREA AIRPORTS THROUGH ABOUT 24Z. THESE STORMS WILL HAVE A CHANCE OF PRODUCING VARIABLE WINDS GUSTING TO 30 KNOTS...AND JUST A SLIGHT CHANCE OF NEEDING INSTRUMENT APPROACHES TO KDEN FOR A SHORT TIME. CLEARING SHOULD OCCUR QUICKLY AFTER 00Z. LIGHT NORTHERLY WINDS SHOULD RETURN TO DRAINAGE WINDS TONIGHT. LITTLE TO NO CONVECTION EXPECTED TOMORROW. A FRONT WILL PUSH THROUGH AFTER 18Z TO TURN WINDS TO THE NORTHEAST...BUT NO THUNDERSTORMS ARE EXPECTED OVER THE AREA AIRPORTS AT THIS TIME. && .HYDROLOGY... ISSUED AT 328 PM MDT TUE AUG 5 2014 BRIEF HEAVY RAIN...UP TO HALF AN INCH IN 15 MINUTES...WILL ACCOMPANY SOME OF THE STRONGER STORMS TODAY. THERE COULD BE SOME AREAS THAT MAY SEE UP TO AN INCH AS TRAINING OF STORMS OCCUR. OVERALL STORM MOTION SHOULD BE ENOUGH TO KEEP THE THREAT OF FLASH FLOODING LOW...EXCEPT IN THE CASE OF TRAINING...ESPECIALLY OVER A BURN SCAR OR STEEP TERRAIN. STORMS WILL BE DECREASING THROUGH MID EVENING AND SHOULD BE DONE BY BEFORE MIDNIGHT. HEAVY RAIN CHANCES ARE LOW THROUGH THE EXTENDED PERIOD. SCATTERED T-STORMS ACROSS THE NORTHEAST CORNER OF THE STATE LATE THURSDAY AND FRIDAY HAVE THE POTENTIAL TO PRODUCE LOCALLY HEAVY RAINFALL. HOWEVER THE THREAT OF FLOODING APPEARS LOW. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KRIEDERMAN LONG TERM...D-L AVIATION...KRIEDERMAN HYDROLOGY...KRIEDERMAN
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1107 PM MDT MON AUG 4 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 213 PM MDT MON AUG 4 2014 .CURRENTLY...STORMS HAVE DEVELOPED OVER THE SOUTHWEST MOUNTAINS AND EASTERN MOUNTAINS THIS AFTERNOON. STORMS HAVE BEEN PRODUCING SOME LOCALLY HEAVY DOWNPOURS...WITH THE MAIN CONCERN BEING FOR THE STORMS TO MOVE SLOWLY OVER THE AREA BURN SCARS. SATELLITE SOUNDER DATA AND MODELS CONTINUE TO MOIST ATMOSPHERE WITH PRECIPITABLE WATERS MOSTLY RANGING FROM 0.75 TO ONE INCH OVER THE MOUNTAINS AND HIGH VALLEYS TO AROUND AN INCH ON THE PLAINS. .TONIGHT...HRRR AND 4KM NAM MODELS CONTINUE TO SUGGEST THE FIRST ROUND OF CONVECTION MOVING OFF OF THE MOUNTAINS IT THE LATER AFTERNOON AND EARLY EVENING. MODELS AND BUFKIT SOUNDINGS CONTINUE TO SHOW WEAK INSTABILITY ON THE PLAINS THIS EVENING...BECOMING MORE CAPPED FURTHER EAST. CONVECTION SHOULD WEAKEN AS IT MOVES EAST DURING THE EVENING...AND MAINTAINED THE SILENT POPS NEAR THE KANSAS BORDER. HRRR SUGGESTS THE NEXT DISTURBANCE...AS SEEN IN CONVECTION OVER NORTHWEST NEW MEXICO...WILL PASS MOVE NORTHEAST ACROSS THE CWA DURING THE EVENING REACHING THE EASTERN MOUNTAINS AFTER MIDNIGHT. SUSPECT ATMOSPHERE WILL BE STABLE BY MIDNIGHT...AND ONLY MAINTAINED POPS OVER THE WESTERN MOUNTAINS AT 06Z. .TUESDAY...PORTION OF SHORTWAVE SPINNING OVER NEVADA WILL CROSS THE CWA DURING THE AFTERNOON. PRECIPITABLE WATER VALUES WILL REMAIN AROUND AN INCH OVER THE MAINS AND 0.75 TO ONE INCH OVER THE MOUNTAINS. WITH THE SHORTWAVE APPROACHING...STORMS WILL DEVELOP AN HOUR TO TWO EARLIER THAN MONDAY. MAIN THREATS AGAIN WILL BE LOCALLY HEAVY DOWNPOURS..ESPECIALLY ON AREA BURN SCARS. WINDS ALOFT WILL INCREASE SO STORMS WILL BE MOVING SLIGHTLY FASTER. BEHIND THE TROUGH...DRYING OCCURS IN THE MID AND UPPER LEVELS BY LATER AFTERNOON. -PGW-- .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 213 PM MDT MON AUG 4 2014 TUE NIGHT... DISTURBANCE ALOFT SHOULD BE OVER EASTERN PLAINS WITH DRIER AIR GRADUALLY MOVING INTO THE MTNS. BEST CHANCE OF PRECIP WILL BE OVER THE FAR E PLAINS DURING THE EVENING...WITH ISOLD POPS (AT BEST) OVER THE CONTDVD. WED... SHOULD BE A RATHER DRY DAY AS DRIER AIR IS FCST TO BE OVER THE MTNS WITH THE DRIER ATMOSPHERE CREEPING INTO THE PLAINS. IN ADDITION...RIDGING AT MIDLVLS WILL BE OCCURRING OVER THE REGION. BELIEVE POPS THIS DAT WILL BE ISOLD AT BEST...AND WILL BE OVER THE HIGHEST TRRN. MAX TEMPS THIS DAY WILL BE WARM WITH HIGHS IN THE 90S MOST OF THE PLAINS. THU... THIS DAY WILL BE TRICKY. A COOL FRONT WILL MOVE ACROSS THE PLAINS EARLY IN THE DAY. CONVECTION WILL FIRE ACROSS THE HIGH PLAINS...BUT HOW FAR SOUTH WILL IT GET? GFS IS FARTHEST NORTH WITH BRUNT OF ACTIVITY OVER FAR NE CO...WHILE NAM AND EC ARE A BIT FARTHER SOUTH WITH THE ACTIVITY EXTENDING DOWN INTO EAST CENTRAL CO. FOR NOW HAVE PAINTED ISOLD POPS OVER THE ENTIRE REGION DURING THE AFTERNOON AND EVENING...BUT MAY NEED HIGHER POPS OVER THE FAR E PLAINS IN LATER UPDATES. MAX TEMPS ON THE PLAINS SHOULD BE AROUND 90F THIS DAY. MTNS SHOULD SEE ONLY ISOLD POPS. FRI... EC AND GFS IN DISAGREEMENT THIS DAY. BOTH BRING DOWN ANOTHER BOUNDARY WITH UPSLOPE FLOW. GFS APPEARS MORE STABLE AND KEEPS WX DRIER OVER OUR REGION WHILE EC A BIT MORE WETTER OVER THE FAR E PLAINS. FOR NOW KEPT ONLY ISOLD POPS OVER E PLAINS WITH ISOLD PRECIP OVER S MTN TOPS. REST OF MTNS DRY. MAX TEMPS ONCE AGAIN ABOUT 90F MOST OF PLAINS. WEEKEND... SIMULATIONS SHOW A BIT BETTER CHANCE OF PRECIP ALL AREAS AS MONSOON PLUME WILL LIKELY REDEVELOP OVER THE SW...WITH MOISTURE ADVECTING IN FROM E AZ AND W NM. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1057 PM MDT MON AUG 4 2014 VFR CIGS EXPECTED AT TAF SITES OVERNIGHT WITH ACTIVE MONSOON PLUME KEEPING -SHRA/-TSRA GOING OVER THE MOUNTAINS THROUGH THE NIGHT. A PASSING -SHRA COULD AFFECT THE KALS TAF SITE TOMORROW MORNING AS A DISTURBANCE WORKS ITS WAY EASTWARD ACROSS THE STATE. -TSRA WILL DEVELOP OVER THE EASTERN MOUNTAINS DURING THE MORNING WHICH WILL MOVE OFF INTO THE ADJACENT KCOS AND KPUB TAF SITES DURING THE EARLY AFTERNOON. ERRATIC WIND GUSTS UP TO 30 KTS AN LIGHTNING WILL BE THE PRIMARY THREATS. CIGS COULD BRIEFLY DROP INTO THE MVFR CATEGORY WITH LOCALLY HEAVY RAINFALL SHOULD A STRONGER STORM AFFECT THE TERMINALS. GIVEN THE HIT OR MISS NATURE TO THUNDERSTORMS TOMORROW WILL MAINTAIN VCTS IN THE TAFS FOR NOW. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...PGW LONG TERM...HODANISH AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
500 PM EDT TUE AUG 5 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION TONIGHT. A SECONDARY COLD FRONT WILL CROSS THE REGION ON THURSDAY. HIGH PRESSURE WILL SETTLED IN FRIDAY THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... AS OF 500 PM EDT...WIDELY SCATTERED THUNDERSTORMS WERE ACROSS OUR REGION...MOST NUMEROUS ACROSS WASHINGTON COUNTY WHERE EARLIER A SEVERE THUNDERSTORM WARNING WAS ISSUED. THIS STORM PRODUCED WIND DAMAGE NEAR HEWITT`S LANDING. MEANWHILE...A CLUSTER OF SHOWERS AND THUNDERSTORMS OVER WESTERN AND CENTRAL NEW YORK...ASSOCIATED WITH A COLD FRONT (ENHANCING SURFACE CONVERGENCE) AND THE EXIT REGION OF THE UPPER LEVEL JET (ENHANCING DIVERGENCE ALOFT) ...CONTINUE TO MOVE STEADILY EAST. IT LOOKS AS IF THIS AREA OF RAIN MIGHT STAY JUST FROM THE CAPITAL REGION SOUTHWARD. THE LATEST HRRR HAS TRENDED A LITTLE SLOWER AND SOUTH WITH THE HEAVIEST RAINFALL...MAINLY JUST SOUTH OF THE CAPITAL REGION THIS EVENING. WILL CONTINUE CHANCE POPS THROUGH ALL OF THE EVENING...INCLUDING THUNDER. GIVEN INSTABILITY AROUND 2000 J/KG...LAPSE RATES OVER 6.0 C/KM...AND ALREADY HISTORY OF ONE DAMAGING WIND THUNDERSTORM AND SMALL HAIL...WE WENT AHEAD AND ADDED QUALIFIER TO THE THUNDERSTORMS THROUGH THIS EVENING..."MIGHT CONTAIN GUSTY WINDS AND SMALL HAIL." SO THROUGH EVENING...EXPECT SCATTERED SHOWERS AND THUNDERSTORMS (MEANING NOT EVERYONE WILL RECEIVE MEASURABLE RAINFALL...BUT SOME AREAS GET A GOOD SOAKING RAIN AND THUNDERSTORM ACTIVITY). IT WILL REMAIN QUITE WARM AND SOMEWHAT HUMID WITH TEMPERATURES IN THE MID TO UPPER 80S...COOLING TO THE 70S LATER THIS EVENING...ESPECIALLY WHERE RAINFALL COOLS THE COLUMN. THE WIND WILL BE VARIABLE SHIFTING TO NORTHWESTERLY LATER TONIGHT BEHIND THE FRONT GENERALLY 10 MPH OR LESS. OVERNIGHT...THE FRONT WILL LIKELY STILL BE SOMEWHERE TO THE SOUTH OF THE CAPITAL REGION. SHOWERS AND THUNDERSTORMS WILL DIMINISH ALL TOGETHER AS UPPER LEVEL FORCING (THE JET EXIT REGION) LIFTS NORTH AND INSTABILITY DISSIPATES. THE SKY WILL PARTIALLY CLEAR. THIS MIGHT ALLOW FOR SOME FOG TO FORM. HOWEVER...THERE MIGHT BE JUST ENOUGH OF A BREEZE TO PREVENT THIS. FOR NOW...DECIDED NOT INCLUDE ANY FOG TONIGHT PENDING HOW MUCH RAINFALLS AND MAKES THE GROUND WET. OVERNIGHT LOWS WILL GENERALLY RANGED FROM THE MID 50S NORTHWEST AND LOWER 60S CAPITAL REGION SOUTHWARD. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/... SOMEWHAT DRIER AND COOLER AIR WILL FILTER INTO THE REGION ON WEDNESDAY BEHIND THE COLD FRONT. HOWEVER...THE ACTUAL FRONT WILL LIKELY STILL BE JUST TO THE SOUTH OF THE CAPITAL REGION. THERE COULD BE A RENEWAL OF SHOWER AND THUNDERSTORM ACTIVITY MAINLY SOUTH OF THE CAPITAL REGION AS SOON AS WE GET HEATING...MAINLY MIDDAY AND AFTERNOON. WILL CONTINUE WITH SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS ALBANY NORTH...LOW CHANCES SOUTH ON WEDNESDAY. WITH LINGERING CLOUDS AND WEAK COOL AIR ADVECTION...WENT WITH THE LOWER END OF GUIDANCE FOR HIGH TEMPERATURES. LOOK FOR HIGHS WEDNESDAY GENERALLY IN THE MID TO UPPER 70S (MORE CLOUDS SOUTH). ANY AND ALL CONVECTION WILL DIMINISH WEDNESDAY NIGHT. WE WILL BE LEFT WITH A MAINLY CLEAR SKY AND PERHAPS SOME PATCHY FOG. DID PUT PATCHY FOG IN THE GRIDS TOMORROW NIGHT AS THE WIND LOOKS CALMER AND LESS IN THE WAY OF CLOUDS. TEMPERATURES WILL DIP INTO 50S. THURSDAY...IT LOOKS AS IF A SECONDARY COLD FRONT AND UPPER LEVEL ENERGY WILL WORK THROUGH TO PRODUCE SOME MORE SCATTERED SHOWERS AND POSSIBLY AFTERNOON THUNDERSTORMS. THE ACTIVITY LOOKS SCATTERED ACROSS THE HIGHER ELEVATIONS AND ISOLATED CAPITAL REGION SOUTHWARD. THE DAY WILL START OUT MAINLY SUNNY...BUT CLOUDS AND THE WIDELY SCATTERED SHOWERS WILL QUICKLY FOLLOW BY AFTERNOON. TEMPERATURES WILL BE SIMILAR TO WEDNESDAY...MAYBE A POINT OR TWO LOWER. IT SHOULD CLEAR OUT THURSDAY NIGHT AND BECOME RATHER COOL. OVERNIGHT LOWS WILL DIP INTO THE LOWER TO MID 50S ALBANY SOUTHWARD...MID TO UPPER 40S FURTHER NORTH. FRIDAY LOOKS LIKE A WINNER WEATHER WISE AS HIGH PRESSURE FROM CANADA BEGINS TO BUILD IN. IT SHOULD BE MOSTLY SUNNY (FEW-SCT FAIR WEATHER CU) AND TEMPERATURES AROUND 80 IN THE VALLEYS...MID TO UPPER 70S HIGHER TERRAIN. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... EXCEPT FOR POSSIBLY THE LAST DAY...THIS WILL BE A STRETCH OF DRY WEATHER AND SEASONABLE TEMPERATURES. HIGH PRESSURE WILL RULE THE ROOST THROUGHOUT. ON TUESDAY...A COLD FRONT FROM THE NORTHWEST MAY MAKE IT CLOSE ENOUGH TO BRING SHOWERS AND THUNDERSTORMS TO THE ADIRONDACKS. RELATIVE HUMIDITIES WILL INCREASE ONLY SLIGHTLY EACH DAY. HIGH TEMPERATURES EACH DAY WILL RANGE FROM THE LOWER AND MID 70S IN THE HIGHEST ELEVATIONS...TO THE LOWER AND MID 80S IN THE VALLEYS. LOW TEMPERATURES WILL GRADUALLY MODERATE SLIGHTLY...WITH LOWS FRIDAY NIGHT FROM MOSTLY THE UPPER 40S IN THE HIGH MOUNTAIN PEAKS...TO THE MID AND UPPER 50S IN THE VALLEYS. BY MONDAY NIGHT...LOWS WILL RANGE FROM THE LOWER AND MID 50S IN THE MOUNTAINS...TO THE LOWER 60S IN THE VALLEYS. FOR THIS PERIOD...NORMAL HIGHS IN ALBANY ARE IN THE LOWER 80S...NORMAL LOWS...AROUND 60 DEGREES. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... MAINLY VFR FLYING CONDITIONS WILL PERSIST THROUGHOUT THE AFTERNOON HOURS WITH BRIEF PERIODS OF MVFR CONDITIONS ASSOCIATED WITH SHOWERS/THUNDERSTORMS...BEFORE MVFR/IFR FOG RETURNS TONIGHT. THIS AFTERNOON...DAYTIME HEATING HAS HELPED SPAWN SCATTERED TO BROKEN CUMULUS AROUND 5-7 KFT...AND WIDELY SCATTERED SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. THE SHOWERS AND THUNDERSTORMS WILL BE SCATTERED IN NATURE THROUGHOUT THE AFTERNOON HOURS SO HAVE PLACED VCSH IN THE TAFS WITH TEMPO GROUPS TO ACCOUNT FOR BRIEF REDUCTIONS TO MVFR ASSOCIATED WITH ANY SHOWERS/STORMS. SOME OF THE STORMS MAY CONTAIN HEAVY DOWNPOURS AND GUSTY WINDS. WINDS WILL BE OUT OF THE SOUTH/SOUTHWEST AT 5-10 KNOTS. TONIGHT INTO WEDNESDAY...THE THUNDERSTORM THREAT WILL DIMINISH AFTER SUNSET WITH SOME LINGERING SHOWERS AT THE TAF SITES THROUGH 03Z AS THE COLD FRONT MOVES ACROSS THE REGION. BEHIND THE FRONT...SKIES WILL CLEAR ALLOWING FOR MVFR/IFR FOG TO RETURN TO THE TAF SITES...ESPECIALLY WHERE SIGNIFICANT RAINFALL OCCURS FROM ANY CONVECTION. VFR FLYING CONDITIONS LOOK TO RETURN AFTER 12Z WEDNESDAY AS AN AREA OF HIGH PRESSURE BEGINS TO SLOWLY BUILD INTO THE REGION. WINDS TONIGHT WILL TREND CALM BEFORE BECOMING LIGHT AND VARIABLE AROUND 5 KNOTS WEDNESDAY. OUTLOOK... WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...TSRA. THURSDAY NIGHT THROUGH SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... SCATTERED SHOWERS AND THUNDERSTORMS THROUGH EVENING...WITH ABOUT HALF THE PLACES RECEIVING A QUARTER INCH OR MORE OF RAINFALL...BUT AREAS NOT RECEIVING ANY. THESE STORMS WILL BE ASSOCIATED WITH A SLOW MOVING COLD FRONT THAT WILL STILL BE WORKING THROUGH AREAS SOUTH OF ALBANY ON WEDNESDAY...THUS CONTINUING THE CHANCES FOR SHOWERS AND THUNDERSTORMS. COVERAGE ON WEDNESDAY WILL BE MORE LIMITED THAN TODAY. A SECONDARY COLD FRONT COULD TRIGGER A FEW MORE SHOWERS AND THUNDERSTORMS ON THURSDAY...MAINLY NORTH AND WEST OF THE CAPITAL REGION. AFTER THAT...IT LOOKS LIKE DRY WEATHER ON THE WEEKEND INTO EARLY NEXT WEEK WITH A NORMAL RECOVERY EACH NIGHT AND RH VALUES GENERALLY 35-45 PERCENT EACH AFTERNOON. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS WILL BE WORKING THROUGH THE REGION THROUGH THE EVENING HOURS. SOME OF THE STORMS HAVE BEEN SLOW MOVING...AND BACKBUILDING...CAPABLE OF PRODUCING RAINFALL IN EXCESS OF AN INCH PER HOUR. LOCALIZED PONDING OF WATER IS POSSIBLE THIS EVENING WITH THESE TYPE OF STORMS...BUT OVERALL...NO SIGNIFICANT HYDRO PROBLEMS ARE ANTICIPATED. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS COULD LINGER FROM THE CAPITAL REGION SOUTHWARD TOMORROW BUT ANY EXCESS RAINFALL WILL PROBABLY BE EVEN MORE LIMITED. ANOTHER COLD FRONT COULD TRIGGER A FEW MORE SHOWERS AND THUNDERSTORMS MAINLY NORTH ON THURSDAY...GENERALLY WITH AN AVERAGE RAINFALL BASIN OF A QUARTER INCH OR LESS. AFTER THAT...DRY WEATHER EXPECTED FRIDAY THROUGH EARLY NEXT WEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...HWJIV NEAR TERM...HWJIV SHORT TERM...HWJIV LONG TERM...ELH AVIATION...IRL FIRE WEATHER...HWJIV HYDROLOGY...HWJIV
AREA FORECAST DISCUSSION
NWS TAUNTON MA
254 PM EDT TUE AUG 5 2014 .SYNOPSIS... SCATTERED SHOWERS AND THUNDERSTORMS ARE ANTICIPATED LATE TODAY AND AGAIN ON WEDNESDAY AS HURRICANE BERTHA PASSES WELL OFFSHORE OF NEW ENGLAND WITH LITTLE IMPACT OTHER THAN HIGH SURF AND DANGEROUS RIP CURRENTS. A COLD FRONT WILL MOVE OFFSHORE WEDNESDAY NIGHT. UPPER TROUGH LINGERS OVER THE REGION THURSDAY AND MOVES EAST DURING FRIDAY. HIGH PRESSURE BUILDS OVER THE REGION FOR THE WEEKEND AND EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1050 AM UPDATE... MONITORING BOTH KENX AND KOKX RADARS...SAW A LONELY SHOWER MOVE ACROSS CENTRAL VT INTO CENTRAL NH BEFORE DISSIPATING AROUND 14Z. ALSO SEE A BAND OF CUMULUS CLOUDS FORMING ALONG DEVELOPING SEA BREEZE FRONT ACROSS S CT ON LATEST VISIBLE SATELLITE LOOP. WILL CONTINUE TO MONITOR RADAR FOR SHOWER DEVELOPMENT...IF IT OCCURS DURING THE EARLY AFTERNOON. NOTING LATEST HRRR FORECAST RADAR TRENDS INDICATING ISOLD SHOWERS ACROSS S NH/N MA AND POSSIBLY ALONG SEA BREEZE FRONT ACROSS S CT...BUT AGAIN WILL MONITOR. TEMPS HAVE RISEN STEADILY SINCE SUNRISE...WITH READINGS IN THE 70S TO LOWER 80S AT 15Z...UP TO 84 AT KFIT. TEMPS/DEWPTS WERE CLOSE TO FORECASTED TRENDS. HAVE UPDATED GRIDS TO BRING CONDITIONS CURRENT. PREVIOUS DISCUSSION... BERTHA TO THE SE WHILE A BROAD-TROUGH SWEEPS ACROSS THE GREAT LAKES. PREVAILING SUBSIDENCE/DRY AIR /H85-H3/ BETWEEN THE TWO COLLOCATED WITH THE LEFT-ENTRANCE REGION OF THE H3 JET SHOULD RESULT IN QUIET WEATHER ACROSS S NEW ENGLAND INTO AFTERNOON. BUT WITH THE WESTERN APPROACH OF A COLD FRONT ASSOCIATED WITH THE BROAD H5 TROUGH...EXPECT THE INCREASE OF CYCLONIC FLOW AND ENHANCED ASCENT ALLOWING THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS OVER W MA / CT AND SW NH. COULD ALSO SEE ACTIVITY ASSOCIATED WITH LOCALIZED CONVERGENCE ALONG SEA-BREEZE BOUNDARIES. CONSIDERING INSTABILITY OF AROUND 1000 J/KG ALONG WITH 30 KTS OF BULK SHEAR...ORDINARY TO MULTI-CELLULAR CONVECTION IS ANTICIPATED. NOTING FORECAST SOUNDINGS WITH FREEZING LEVELS AROUND 10 KFT ALONG WITH A COMBINATION OF THIN-CAPE AND POTENTIAL INVERTED-V PROFILES... FEEL THERE IS AN ISOLATED THREAT OF HEAVY RAIN...STRONG TO DAMAGING WINDS...AND SMALL HAIL /IN PRIORITY OF CONCERN/. WARM AND HUMID CONDITIONS CONTINUING AS TEMPERATURES WARM TO AROUND THE MID-80S WITH DEWPOINTS RANGING AROUND THE MID-60S. COOLER ALONG THE SHORELINES WITH ANTICIPATED SEA-BREEZES. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... TONIGHT... COLD FRONTAL BOUNDARY CONTINUES TO SWEEP INTO S NEW ENGLAND. EXPECT SCATTERED SHOWER / THUNDERSTORM ACTIVITY...STRONGEST OF WHICH WILL CONTINUE TO BE ACROSS N/W INTERIOR...WEAKENING OVER TIME WITH THE LACK OF DAY-TIME HEATING AND INSTABILITY. FALLING HEIGHTS / CYCLONIC FLOW MAY PROLONG SHOWER ACTIVITY TILL AFTER MIDNIGHT AND TOWARDS THE COASTLINES. OTHERWISE...SOUPY AIR WITH DEWPOINTS AROUND THE MID-60S MAINTAINED BY SW FLOW WILL LIKELY RESULT IN ANOTHER NIGHT OF LOW-CLOUDS AND DENSE FOG FOR PORTIONS OF S/SE NEW ENGLAND ESPECIALLY ALONG THE SHORELINES. DRIER AIR BUILDING IN BEHIND THE FRONT SHOULD KEEP AREAS OF THE N/W INTERIOR FOG-FREE. LOWS NW-SE RANGING FROM THE LOW-60S TO UPPER-60S. WEDNESDAY... SYNOPTICALLY...IGNORE THE PRESSURE PATTERN. BELIEVE THE OVERNIGHT COLD FRONT BECOMES DIFFUSE AS A BROAD AREA OF LOW PRESSURE SITUATED MAINLY ACROSS SE NEW ENGLAND. AS THE MAIN CRUX OF ENERGY SWEEPS THROUGH THE PREVAILING MID-LEVEL BROAD TROUGH...FALLING HEIGHTS ARE INVOKED THROUGHOUT THE ATMOSPHERIC COLUMN. THE COMBINATION OF THE LEFT-FRONT-QUADRANT ASSOCIATED WITH THE H3 CYCLONIC JET...MID- LEVEL ENHANCED ASCENT...AND LOCALIZED CONVERGENCE OF A SOUPY UNSTABLE AIRMASS ALONG SEA-BREEZE BOUNDARIES...DEEP-LAYER ASCENT PREVAILS. ANTICIPATE SCATTERED SHOWER AND THUNDERSTORM ACTIVITY MAINLY ACROSS S/E INTERIOR NEW ENGLAND INCORPORATING E MA AND RI. ASSUMING INSTABILITY VALUES AROUND 1000 J/KG WILL BE MET IN AN ENVIRONMENT OF AVERAGE 30 KT W-E UNI-DIRECTIONAL SHEAR SHOULD YIELD ORDINARY TO MULTI-CELLULAR CONVECTION ALONG THE SEA-BREEZE BOUNDARIES. PWATS RANGE 1.0 - 1.5 INCHES. ONCE AGAIN...NOTING FORECAST SOUNDINGS WITH FREEZING LEVELS AROUND 10 KFT ALONG WITH A COMBINATION OF THIN-CAPE AND POTENTIAL INVERTED-V PROFILES...FEEL THERE IS AN ISOLATED THREAT OF HEAVY RAIN...STRONG TO DAMAGING WINDS...AND SMALL HAIL /IN PRIORITY OF CONCERN/. A GREATER THREAT OF URBAN FLOODING IS CERTAINLY PLAUSIBLE SHOULD STORMS PERPETUATE ALONG THE SEA-BREEZE. WARM AND MUGGY CONDITIONS EXPECTED MORE S/E WITH HIGHS AROUND THE UPPER-70S. COOLER AND DRIER N/W THOUGH LOW-80S POSSIBLE OVER THE LOWER CT-VALLEY. && .LONG TERM /THURSDAY THROUGH TUESDAY/... BIG PICTURE... UPPER TROUGH AND COLD POOL MOVE EAST FROM THE GREAT LAKES...REACHING NEW ENGLAND THURSDAY AND THE MARITIMES FRIDAY. UPPER RIDGE THEN BUILDS OVER THE REGION. THIS SHOULD BRING DRY WEATHER AND WARM TEMPERATURES THROUGH EARLY NEXT WEEK. THE DAILIES... THURSDAY-FRIDAY... COLD AIR ALOFT WITHIN THE UPPER TROUGH WILL DESTABILIZE THE AIRMASS. TOTALS ON THURSDAY ARE EXPECTED TO REACH THE MID 50S...WITH A MOIST LAYER BETWEEN 875 AND 825 MB. EXPECT DIURNAL CUMULUS ALONG WITH SCATTERED SHOWERS/TSTMS THURSDAY. TEMPS ALOFT WARM A LITTLE FRIDAY BUT SIMILAR MOIST LAYER ALOFT. EXPECT DIURNAL CLOUDS FRIDAY BUT WITH MORE ISOLATED SHOWERS. MIXING TO 850 MB THURSDAY AND AT LEAST 825 MB FRIDAY...SUPPORTING MAX TEMPS IN THE UPPER 70S THURSDAY AND LOWER 80S FRIDAY. GFS SUGGESTS SEA BREEZE EACH DAY...PRESSURE GRADIENT SEEMS TO CONFLICT WITH THIS THURSDAY BUT IS SUPPORTIVE FOR FRIDAY. ECMWF SUPPORTS SEA BREEZES BOTH DAYS WITH A WEAK PRESSURE GRADIENT IN PLACE. SATURDAY THROUGH MONDAY... HIGH PRESSURE BUILDS OVER THE REGION. LIGHT WINDS WITH ONSHORE FLOW NEAR THE COAST. TEMPS ALOFT SUPPORT LOW-MID 80S INLAND AND COOLER TEMPS NEAR THE COAST. TUESDAY... HIGH PRESSURE STILL IN CONTROL AND SHOULD PROVIDE A FAIR WEATHER DAY. LOW PRESSURE IN THE SOUTHERN STREAM RACES OUT TO SEA WELL SOUTH OF NEW ENGLAND...BUT COULD SPREAD A FEW CLOUDS OUR WAY ON TUESDAY. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THROUGH WEDNESDAY... THIS AFTERNOON...MODERATE CONFIDENCE. EXPECT MAINLY VFR ACROSS MOST AREAS...BUT LOCAL MVFR-IFR MAY LINGER ACROSS KACK THROUGH 18Z OR SO. SOME ISOLD -SHRA/TSRA POSSIBLE...ESPECIALLY INTERIOR TERMINALS. WINDS MAINLY W-SW. SEA BREEZES FOR COASTAL TERMINALS. TONIGHT...MODERATE CONFIDENCE. SHRA/TSRA DISSIPATING AROUND 3Z ACROSS INTERIOR S NEW ENGLAND. WILL SEE THE RETURN OF MVFR-VLIFR CIGS/VSBYS...MAINLY FOR S/E NEW ENGLAND COASTLINES. WEDNESDAY... MVFR-VLIFR CIGS/VSBYS DISSIPATE. SEA-BREEZES AROUND 15Z BECOME THE FOCUS FOR SHRA/TSRA ACROSS INTERIOR E/SE MA AND ALL OF RI. ACTIVITY FURTHER W POSSIBLE. KBOS TERMINAL...MODERATE CONFIDENCE. LIGHT SEA BREEZE THROUGH 22Z-23Z. KBDL TERMINAL...HIGH CONFIDENCE. OUTLOOK...THURSDAY THROUGH SUNDAY...MODERATE CONFIDENCE. THURSDAY-FRIDAY...VFR. BRIEF MVFR CIGS/VSBYS POSSIBLE IN AFTERNOON SHOWER OR THUNDERSTORM...MAINLY THURSDAY. SATURDAY-SUNDAY...VFR. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THIS AFTERNOON THROUGH WEDNESDAY... SWELLS WILL INCREASE AS BERTHA MAKES ITS CLOSEST APPROACH LATE TONIGHT. THIS WILL LEND TO INCREASING WAVE HEIGHTS ACROSS THE S/SE WATERS. SMALL CRAFT ADVISORIES FOR HAZARDOUS SEAS ISSUED ACCORDINGLY WITH WAVE HEIGHTS UP TO 7 FEET POSSIBLE. THE DELAY IN SWELL AND LIGHT WINDS FOR TODAY WILL LIMIT THE RIP CURRENT RISK...BUT WILL NEED TO WATCH FOR POTENTIAL HAZARDS TONIGHT INTO WEDNESDAY. LOW CLOUDS AND FOG WILL RETURN LATE TONIGHT INTO WEDNESDAY MORNING...WITH VSBYS AGAIN BELOW 1SM IN SOME AREAS MAINLY S COAST...CAPE COD AND THE ISLANDS. OUTLOOK...THURSDAY THROUGH SUNDAY...MODERATE CONFIDENCE. HIGH PRESSURE BUILDS FROM THE WEST. LINGERING CHANCE OF A THUNDERSTORM THURSDAY AFTERNOON...ESPECIALLY NEARSHORE. THERE MAY BE A LINGERING 5 FOOT SWELL ON THE SOUTHERN OUTER WATERS FROM TROPICAL STORM BERTHA THURSDAY MORNING...BUT THIS SHOULD SUBSIDE DURING THE DAY. OTHERWISE...WINDS AND SEAS SHOULD REMAIN BELOW SMALL CRAFT ADVISORY THRESHOLDS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM MIDNIGHT TONIGHT TO 6 PM EDT WEDNESDAY FOR ANZ235-237-254>256. && $$ SYNOPSIS...WTB/SIPPRELL NEAR TERM...DOODY/SIPPRELL/EVT SHORT TERM...SIPPRELL LONG TERM...WTB AVIATION...WTB/SIPPRELL MARINE...WTB/SIPPRELL/EVT
AREA FORECAST DISCUSSION
NWS ALBANY NY
138 PM EDT TUE AUG 5 2014 .SYNOPSIS... PARTLY SUNNY AND WARM WEATHER IS EXPECTED TODAY. A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA LATER TODAY AND WEDNESDAY BEFORE CLEARING THE REGION. COOL AND BREEZY WEATHER...WITH A CONTINUED THREAT OF AFTERNOON SHOWERS...IS FORECAST FOR THURSDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 100 PM EDT...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WERE BEGINNING TO POPPING UP ACROSS MUCH OF AREA. IT APPEARS OUR CAP MIGHT BE BREAKING ALREADY. THE BUF RAOB INDICATED LESS CAPPING AS THE ATMOSPHERE ALOFT BEGINS COOLING OFF AHEAD OF A COLD FRONT. STORMS COULD BECOME MORE PRONOUNCED LATER ON. WE WERE FOLLOWING A CLUSTER OF THUNDERSTORMS WORKING TOWARD EXTREME SW NY. THE LATEST HRRR MODEL INDICATED THESE WOULD HOLD TOGETHER AND MAKE INTO OUR REGION AROUND 00Z-02Z...MAINLY SOUTH OF ALBANY...BUT THEN TRANSITIONING INTO A MORE SYNOPTIC RAIN EVENT. THIS IDEA WAS NOT SUPPORT BY LATEST NAM AND GFS MODELS NOR THE LOCAL HIRESWRF. WE WILL CONTINUE TO MONITOR BUT FOR NOW EXPECT CONVECTIVE ACTIVITY WILL PICK UP A LITTLE THIS AFTERNOON DUE TO DIURNAL HEATING AND COOLING ALOFT. THE CLUSTER...OR WHAT IS LEFT OF IT...WILL MAKE IT INTO A PORTION OF AREA THIS EVENING...ASSUMING IT CAN HOLD TOGETHER. THUNDERSTORMS LATER THIS AFTERNOON...COULD PRODUCE LOCALIZED WIND GUSTS AND HEAVY RAINFALL...BUT THE THREAT WAS DEEMED TOO LOW TO ADD ENHANCED WORDING TO THUNDERSTORMS AT THIS TIME. WITH STRONG DAYTIME HEATING EXPECTED...TEMPS WILL REACH INTO THE MID AND UPPER 80S ACROSS MUCH OF THE REGION EXCEPT FOR UPPER 70S TO LOW 80S ACROSS THE SOUTHERN ADIRONDACKS. COMBINED WITH DEWPOINTS IN THE LOW TO MID 60S AND MARGINAL MIDLEVEL LAPSE RATES AROUND 6.0 C/KM...AROUND 500-1500 J/KG OF SBCAPE IS EXPECTED BY MID AFTERNOON. THERE WILL BE LITTLE IN THE WAY OF DYNAMIC FORCING ACROSS THE REGION...AS A COLD FRONT REMAINS FAR ENOUGH NORTH AND WEST TO ALLOW FOR LOCAL TOPOGRAPHIC/DIFFERENTIAL HEATING BOUNDARIES TO BE THE PRIMARY FOCUS FOR CONVECTION. THE HRRR DEPICTS WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BETWEEN 12PM-2PM...AND PERSISTING THROUGH MUCH OF THE AFTERNOON BEFORE A DECAYING CLUSTER OF STORMS CURRENTLY ACROSS THE LOWER GREAT LAKES REACHES THE REGION BY THE LATE EVENING HOURS. ALTHOUGH THERE WILL BE MODEST INSTABILITY IN PLACE...MEAGER DYNAMIC FORCING WILL RESULT IN MAINLY GENERIC THUNDERSTORM ACTIVITY WITH THE STRONGEST STORMS CAPABLE OF BRIEF HEAVY DOWNPOURS THAT MAY PRODUCE LOCALIZED PONDING OF WATER ON ROADWAYS AS WELL AS IN LOW LYING AND URBAN AREAS. HAVE ONLY GONE WITH SLIGHT CHANCE AND CHANCE POPS AS COVERAGE WILL BE SCATTERED AT BEST. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... ANY LINGERING SHOWERS OR THUNDERSTORMS SHOULD DISSIPATE THROUGH THE EVENING...WITH INTERVALS OF CLOUDS THE REST OF THE NIGHT. THE BETTER UPPER DYNAMICS ASSOCIATED WITH THE UPPER SYSTEM...AND THE BETTER LOW LEVEL FORCING ALONG A TIGHTENING AND ADVANCING BOUNDARY LAYER THERMAL GRADIENT SHOULD SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS WEDNESDAY...MAINLY AFTERNOON AND EVENING. HIGHS WEDNESDAY IN THE MID 70S TO LOWER 80S. ONE LAST LINGERING PIECE OF UPPER ENERGY AND THE UPPER COLD POOL BRUSH JUST NORTH AND NORTHEAST OF OUR REGION THURSDAY SUPPORTING ONE LAST ROUND OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY IN NORTHERN AND EASTERN AREAS. COOLING CONTINUES TO TAKE PLACE ACROSS THE REGION...AND HIGHS SHOULD BE IN THE 70S TO NEAR 80. NIGHTTIME LOWS TONIGHT SHOULD BE IN THE UPPER 50S TO LOWER 60S...COOLER IN HIGHER TERRAIN. FOR WEDNESDAY NIGHT AND THURSDAY NIGHT LOWS IN THE 50S WITH AROUND 50 HIGHER TERRAIN. && .LONG TERM /FRIDAY THROUGH TUESDAY/... FRIDAY WE WILL DEALING WITH THE LAST VESTIGES OF A CYCLONIC FLOW REGIME...WITH POTENTIALLY ONE FINAL WEAK DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY OF AN UPPER LOW OVER THE CANADIAN MARITIMES. SO WILL MENTION JUST SLIGHT CHANCE POPS FOR WESTERN NEW ENGLAND...BEFORE TRANQUIL CONDITIONS DEVELOP FRIDAY NIGHT AS THE FLOW STARTS TO BECOME MORE ANTICYCLONIC. THE WEEKEND LOOKS TO FEATURE PLENTY OF SUNSHINE AND SEASONABLE TEMPERATURES...AS A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT BECOMES ESTABLISHED ACROSS THE REGION. THE 00Z GFS IS ACTUALLY DEVELOPING SOME CONVECTION ON SUNDAY UNDERNEATH THE RIDGE...WHICH IN THE ABSENCE OF ANY SIGNIFICANT MOISTURE AND INSTABILITY LOOKS RATHER SUSPECT. WILL LEAN TOWARD THE 00Z ECMWF WHICH IS INDICATING RAIN-FREE CONDITIONS UNDER THE RIDGE. QUIET WEATHER SHOULD CONTINUE INTO EARLY NEXT WEEK WITH THE RIDGE STILL EXPECTED TO BE IN PLACE ACROSS THE NORTHEAST CONUS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... MAINLY VFR FLYING CONDITIONS WILL PERSIST THROUGHOUT THE AFTERNOON HOURS WITH BRIEF PERIODS OF MVFR CONDITIONS ASSOCIATED WITH SHOWERS/THUNDERSTORMS...BEFORE MVFR/IFR FOG RETURNS TONIGHT. THIS AFTERNOON...DAYTIME HEATING HAS HELPED SPAWN SCATTERED TO BROKEN CUMULUS AROUND 5-7 KFT...AND WIDELY SCATTERED SHOWERS AND THUNDERSTORMS AHEAD OF A COLD FRONT APPROACHING FROM THE NORTHWEST. THE SHOWERS AND THUNDERSTORMS WILL BE SCATTERED IN NATURE THROUGHOUT THE AFTERNOON HOURS SO HAVE PLACED VCSH IN THE TAFS WITH TEMPO GROUPS TO ACCOUNT FOR BRIEF REDUCTIONS TO MVFR ASSOCIATED WITH ANY SHOWERS/STORMS. SOME OF THE STORMS MAY CONTAIN HEAVY DOWNPOURS AND GUSTY WINDS. WINDS WILL BE OUT OF THE SOUTH/SOUTHWEST AT 5-10 KNOTS. TONIGHT INTO WEDNESDAY...THE THUNDERSTORM THREAT WILL DIMINISH AFTER SUNSET WITH SOME LINGERING SHOWERS AT THE TAF SITES THROUGH 03Z AS THE COLD FRONT MOVES ACROSS THE REGION. BEHIND THE FRONT...SKIES WILL CLEAR ALLOWING FOR MVFR/IFR FOG TO RETURN TO THE TAF SITES...ESPECIALLY WHERE SIGNIFICANT RAINFALL OCCURS FROM ANY CONVECTION. VFR FLYING CONDITIONS LOOK TO RETURN AFTER 12Z WEDNESDAY AS AN AREA OF HIGH PRESSURE BEGINS TO SLOWLY BUILD INTO THE REGION. WINDS TONIGHT WILL TREND CALM BEFORE BECOMING LIGHT AND VARIABLE AROUND 5 KNOTS WEDNESDAY. OUTLOOK... WEDNESDAY NIGHT: SLIGHT CHANCE OF SHRA. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA ON TUESDAY AND WEDNESDAY BEFORE CLEARING THE REGION. MINIMUM RELATIVE HUMIDITIES THIS AFTERNOON AND TOMORROW AFTERNOON SHOULD RANGE IN THE 40 TO 55 PERCENT RANGE. NIGHTTIME RH VALUES SHOULD BE 70 TO 100 PERCENT. WINDS WILL BE WEST TO NORTHWEST AT 15 MPH OR LESS THROUGH THE PERIOD. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED EACH AFTERNOON AND EVENING THROUGH WEDNESDAY ASSOCIATED WITH AN ADVANCING COLD FRONT. THE THREAT OF ISOLATED FLOODING OF POOR DRAINAGE AND URBAN AREAS WILL CONTINUE THIS AFTERNOON THROUGH WEDNESDAY... MAINLY IF THUNDERSTORMS REPEATEDLY PASS OVER THE SAME LOCATIONS. DUE TO THE CONVECTIVE NATURE OF THE RAINFALL...MOST RIVER BASINS WILL NOT EXPERIENCE MUCH IMPACT. SOME RISES MAY OCCUR FOR AREAS THAT SEE REPEATED RAINFALL THROUGH MIDWEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...NAS NEAR TERM...SND/HWJIV/IRL SHORT TERM...NAS LONG TERM...JPV AVIATION...IRL FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
0100 PM EDT TUE AUG 5 2014 .SYNOPSIS... PARTLY SUNNY AND WARM WEATHER IS EXPECTED TODAY. A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA LATER TODAY AND WEDNESDAY BEFORE CLEARING THE REGION. COOL AND BREEZY WEATHER...WITH A CONTINUED THREAT OF AFTERNOON SHOWERS...IS FORECAST FOR THURSDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 100 PM EDT...WIDELY SCATTERED SHOWERS AND THUNDERSTORMS WERE BEGINNING TO POPPING UP ACROSS MUCH OF AREA. IT APPEARS OUR CAP MIGHT BE BREAKING ALREADY. THE BUF RAOB INDICATED LESS CAPPING AS THE ATMOSPHERE ALOFT BEGINS COOLING OFF AHEAD OF A COLD FRONT. STORMS COULD BECOME MORE PRONOUNCED LATER ON. WE WERE FOLLOWING A CLUSTER OF THUNDERSTORMS WORKING TOWARD EXTREME SW NY. THE LATEST HRRR MODEL INDICATED THESE WOULD HOLD TOGETHER AND MAKE INTO OUR REGION AROUND 00Z-02Z...MAINLY SOUTH OF ALBANY...BUT THEN TRANSITIONING INTO A MORE SYNOPTIC RAIN EVENT. THIS IDEA WAS NOT SUPPORT BY LATEST NAM AND GFS MODELS NOR THE LOCAL HIRESWRF. WE WILL CONTINUE TO MONITOR BUT FOR NOW EXPECT CONVECTIVE ACTIVITY WILL PICK UP A LITTLE THIS AFTERNOON DUE TO DIURNAL HEATING AND COOLING ALOFT. THE CLUSTER...OR WHAT IS LEFT OF IT...WILL MAKE IT INTO A PORTION OF AREA THIS EVENING...ASSUMING IT CAN HOLD TOGETHER. THUNDERSTORMS LATER THIS AFTERNOON...COULD PRODUCE LOCALIZED WIND GUSTS AND HEAVY RAINFALL...BUT THE THREAT WAS DEEMED TOO LOW TO ADD ENHANCED WORDING TO THUNDERSTORMS AT THIS TIME. WITH STRONG DAYTIME HEATING EXPECTED...TEMPS WILL REACH INTO THE MID AND UPPER 80S ACROSS MUCH OF THE REGION EXCEPT FOR UPPER 70S TO LOW 80S ACROSS THE SOUTHERN ADIRONDACKS. COMBINED WITH DEWPOINTS IN THE LOW TO MID 60S AND MARGINAL MIDLEVEL LAPSE RATES AROUND 6.0 C/KM...AROUND 500-1500 J/KG OF SBCAPE IS EXPECTED BY MID AFTERNOON. THERE WILL BE LITTLE IN THE WAY OF DYNAMIC FORCING ACROSS THE REGION...AS A COLD FRONT REMAINS FAR ENOUGH NORTH AND WEST TO ALLOW FOR LOCAL TOPOGRAPHIC/DIFFERENTIAL HEATING BOUNDARIES TO BE THE PRIMARY FOCUS FOR CONVECTION. THE HRRR DEPICTS WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BETWEEN 12PM-2PM...AND PERSISTING THROUGH MUCH OF THE AFTERNOON BEFORE A DECAYING CLUSTER OF STORMS CURRENTLY ACROSS THE LOWER GREAT LAKES REACHES THE REGION BY THE LATE EVENING HOURS. ALTHOUGH THERE WILL BE MODEST INSTABILITY IN PLACE...MEAGER DYNAMIC FORCING WILL RESULT IN MAINLY GENERIC THUNDERSTORM ACTIVITY WITH THE STRONGEST STORMS CAPABLE OF BRIEF HEAVY DOWNPOURS THAT MAY PRODUCE LOCALIZED PONDING OF WATER ON ROADWAYS AS WELL AS IN LOW LYING AND URBAN AREAS. HAVE ONLY GONE WITH SLIGHT CHANCE AND CHANCE POPS AS COVERAGE WILL BE SCATTERED AT BEST. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... ANY LINGERING SHOWERS OR THUNDERSTORMS SHOULD DISSIPATE THROUGH THE EVENING...WITH INTERVALS OF CLOUDS THE REST OF THE NIGHT. THE BETTER UPPER DYNAMICS ASSOCIATED WITH THE UPPER SYSTEM...AND THE BETTER LOW LEVEL FORCING ALONG A TIGHTENING AND ADVANCING BOUNDARY LAYER THERMAL GRADIENT SHOULD SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS WEDNESDAY...MAINLY AFTERNOON AND EVENING. HIGHS WEDNESDAY IN THE MID 70S TO LOWER 80S. ONE LAST LINGERING PIECE OF UPPER ENERGY AND THE UPPER COLD POOL BRUSH JUST NORTH AND NORTHEAST OF OUR REGION THURSDAY SUPPORTING ONE LAST ROUND OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY IN NORTHERN AND EASTERN AREAS. COOLING CONTINUES TO TAKE PLACE ACROSS THE REGION...AND HIGHS SHOULD BE IN THE 70S TO NEAR 80. NIGHTTIME LOWS TONIGHT SHOULD BE IN THE UPPER 50S TO LOWER 60S...COOLER IN HIGHER TERRAIN. FOR WEDNESDAY NIGHT AND THURSDAY NIGHT LOWS IN THE 50S WITH AROUND 50 HIGHER TERRAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... FRIDAY WE WILL DEALING WITH THE LAST VESTIGES OF A CYCLONIC FLOW REGIME...WITH POTENTIALLY ONE FINAL WEAK DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY OF AN UPPER LOW OVER THE CANADIAN MARITIMES. SO WILL MENTION JUST SLIGHT CHANCE POPS FOR WESTERN NEW ENGLAND...BEFORE TRANQUIL CONDITIONS DEVELOP FRIDAY NIGHT AS THE FLOW STARTS TO BECOME MORE ANTICYCLONIC. THE WEEKEND LOOKS TO FEATURE PLENTY OF SUNSHINE AND SEASONABLE TEMPERATURES...AS A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT BECOMES ESTABLISHED ACROSS THE REGION. THE 00Z GFS IS ACTUALLY DEVELOPING SOME CONVECTION ON SUNDAY UNDERNEATH THE RIDGE...WHICH IN THE ABSENCE OF ANY SIGNIFICANT MOISTURE AND INSTABILITY LOOKS RATHER SUSPECT. WILL LEAN TOWARD THE 00Z ECMWF WHICH IS INDICATING RAIN-FREE CONDITIONS UNDER THE RIDGE. QUIET WEATHER SHOULD CONTINUE INTO EARLY NEXT WEEK WITH THE RIDGE STILL EXPECTED TO BE IN PLACE ACROSS THE NORTHEAST CONUS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... SATELLITE PICTURES SHOW RADIATION FOG IN MANY OF THE VALLEYS OF EASTERN NEW YORK AND WESTERN NEW ENGLAND. VARIOUS WEB CAMS AROUND THE AREA SHOW THE FOG STEADILY BURNING OFF. MOST OF THE FOG SHOULD BE GONE FROM THE TAF SITES BY 13Z EXCEPT KPSF WHERE IT MAY LINGER UNTIL 14Z. VFR CONDITIONS EXPECTED FOR MOST OF THE DAYLIGHT HOURS. A DISTURBANCE MOVING THROUGH COULD TRIGGER SCATTERED THUNDERSTORMS THIS AFTERNOON...SO HAVE PLACED VCSH IN ALL TAFS STARTING AROUND 19Z OR 20Z. THUNDERSTORMS COULD PRODUCE SOME MVFR AT TAF SITES BUT COVERAGE IS NOT EXPECTED TO BE WIDESPREAD ENOUGH TO PUT THUNDERSTORMS IN THE TAFS. THESE STORMS SHOULD DISSIPATE AFTER SUNSET...WITH SOME PATCHY VALLEY FOG RETURNING WEDNESDAY MORNING. WINDS ARE FORECAST TO BE FROM THE WEST TODAY AND TONIGHT AT 5 TO 15 KNOTS. OUTLOOK... WEDNESDAY NIGHT: SLIGHT CHANCE OF SHRA. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA ON TUESDAY AND WEDNESDAY BEFORE CLEARING THE REGION. MINIMUM RELATIVE HUMIDITIES THIS AFTERNOON AND TOMORROW AFTERNOON SHOULD RANGE IN THE 40 TO 55 PERCENT RANGE. NIGHTTIME RH VALUES SHOULD BE 70 TO 100 PERCENT. WINDS WILL BE WEST TO NORTHWEST AT 15 MPH OR LESS THROUGH THE PERIOD. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED EACH AFTERNOON AND EVENING THROUGH WEDNESDAY ASSOCIATED WITH AN ADVANCING COLD FRONT. THE THREAT OF ISOLATED FLOODING OF POOR DRAINAGE AND URBAN AREAS WILL CONTINUE THIS AFTERNOON THROUGH WEDNESDAY... MAINLY IF THUNDERSTORMS REPEATEDLY PASS OVER THE SAME LOCATIONS. DUE TO THE CONVECTIVE NATURE OF THE RAINFALL...MOST RIVER BASINS WILL NOT EXPERIENCE MUCH IMPACT. SOME RISES MAY OCCUR FOR AREAS THAT SEE REPEATED RAINFALL THROUGH MIDWEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...NAS NEAR TERM...SND/HWJIV/IRL SHORT TERM...NAS LONG TERM...JPV AVIATION...SND/JPV FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS ALBANY NY
1231 PM EDT TUE AUG 5 2014 .SYNOPSIS... PARTLY SUNNY AND WARM WEATHER IS EXPECTED TODAY. A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA LATER TODAY AND WEDNESDAY BEFORE CLEARING THE REGION. COOL AND BREEZY WEATHER...WITH A CONTINUED THREAT OF AFTERNOON SHOWERS...IS FORECAST FOR THURSDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1230 PM EDT...ONE SHOWER BRIEFLY POPPED UP OVER SOUTHERN ALBANY COUNTY...WHILE A FEW MORE OVER THE CATSKILLS. WE BELIEVE THERE WILL BE MORE RANDOM POP UP SHOWERS POSSIBLY DEVELOPING INTO THE THUNDERSTORMS. OUR ALY RAOB INDICATED WE WERE CAPPED SO INITIALLY CELLS SHOULD NOT GROW THAT TALL. HOWEVER...THE BUF RAOB INDICATED LESS CAPPING AS THE ATMOSPHERE ALOFT BEGINS COOLING OFF AHEAD OF A COLD FRONT. STORMS COULD BECOME MORE PRONOUNCED LATER ON. WE WERE FOLLOWING A CLUSTER OF THUNDERSTORMS WORKING TOWARD EXTREME SW NY. THE LATEST HRRR MODEL INDICATED THESE WOULD HOLD TOGETHER AND MAKE INTO OUR REGION AROUND 00Z-02Z...MAINLY SOUTH OF ALBANY...BUT THEN TRANSITIONING INTO A MORE SYNOPTIC RAIN EVENT. THIS IDEA WAS NOT SUPPORT BY LATEST NAM AND GFS MODELS NOR THE LOCAL HIRESWRF. WE WILL CONTINUE TO MONITOR BUT FOR NOW EXPECT CONVECTIVE ACTIVITY WILL PICK UP A LITTLE THIS AFTERNOON DUE TO DIURNAL HEATING AND COOLING ALOFT. THE CLUSTER...OR WHAT IS LEFT OF IT...WILL MAKE IT INTO A PORTION OF AREA THIS EVENING...ASSUMING IT CAN HOLD TOGETHER. THUNDERSTORMS LATER THIS AFTERNOON...COULD PRODUCE LOCALIZED WIND GUSTS AND HEAVY RAINFALL...BUT THE THREAT WAS DEEMED TOO LOW TO ADD ENHANCED WORDING TO THUNDERSTORMS AT THIS TIME. WITH STRONG DAYTIME HEATING EXPECTED...TEMPS WILL REACH INTO THE MID AND UPPER 80S ACROSS MUCH OF THE REGION EXCEPT FOR UPPER 70S TO LOW 80S ACROSS THE SOUTHERN ADIRONDACKS. COMBINED WITH DEWPOINTS IN THE LOW TO MID 60S AND MARGINAL MIDLEVEL LAPSE RATES AROUND 6.0 C/KM...AROUND 500-1500 J/KG OF SBCAPE IS EXPECTED BY MID AFTERNOON. THERE WILL BE LITTLE IN THE WAY OF DYNAMIC FORCING ACROSS THE REGION...AS A COLD FRONT REMAINS FAR ENOUGH NORTH AND WEST TO ALLOW FOR LOCAL TOPOGRAPHIC/DIFFERENTIAL HEATING BOUNDARIES TO BE THE PRIMARY FOCUS FOR CONVECTION. THE HRRR DEPICTS WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BETWEEN 12PM-2PM...AND PERSISTING THROUGH MUCH OF THE AFTERNOON BEFORE A DECAYING CLUSTER OF STORMS CURRENTLY ACROSS THE LOWER GREAT LAKES REACHES THE REGION BY THE LATE EVENING HOURS. ALTHOUGH THERE WILL BE MODEST INSTABILITY IN PLACE...MEAGER DYNAMIC FORCING WILL RESULT IN MAINLY GENERIC THUNDERSTORM ACTIVITY WITH THE STRONGEST STORMS CAPABLE OF BRIEF HEAVY DOWNPOURS THAT MAY PRODUCE LOCALIZED PONDING OF WATER ON ROADWAYS AS WELL AS IN LOW LYING AND URBAN AREAS. HAVE ONLY GONE WITH SLIGHT CHANCE AND CHANCE POPS AS COVERAGE WILL BE SCATTERED AT BEST. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... ANY LINGERING SHOWERS OR THUNDERSTORMS SHOULD DISSIPATE THROUGH THE EVENING...WITH INTERVALS OF CLOUDS THE REST OF THE NIGHT. THE BETTER UPPER DYNAMICS ASSOCIATED WITH THE UPPER SYSTEM...AND THE BETTER LOW LEVEL FORCING ALONG A TIGHTENING AND ADVANCING BOUNDARY LAYER THERMAL GRADIENT SHOULD SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS WEDNESDAY...MAINLY AFTERNOON AND EVENING. HIGHS WEDNESDAY IN THE MID 70S TO LOWER 80S. ONE LAST LINGERING PIECE OF UPPER ENERGY AND THE UPPER COLD POOL BRUSH JUST NORTH AND NORTHEAST OF OUR REGION THURSDAY SUPPORTING ONE LAST ROUND OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY IN NORTHERN AND EASTERN AREAS. COOLING CONTINUES TO TAKE PLACE ACROSS THE REGION...AND HIGHS SHOULD BE IN THE 70S TO NEAR 80. NIGHTTIME LOWS TONIGHT SHOULD BE IN THE UPPER 50S TO LOWER 60S...COOLER IN HIGHER TERRAIN. FOR WEDNESDAY NIGHT AND THURSDAY NIGHT LOWS IN THE 50S WITH AROUND 50 HIGHER TERRAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... FRIDAY WE WILL DEALING WITH THE LAST VESTIGES OF A CYCLONIC FLOW REGIME...WITH POTENTIALLY ONE FINAL WEAK DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY OF AN UPPER LOW OVER THE CANADIAN MARITIMES. SO WILL MENTION JUST SLIGHT CHANCE POPS FOR WESTERN NEW ENGLAND...BEFORE TRANQUIL CONDITIONS DEVELOP FRIDAY NIGHT AS THE FLOW STARTS TO BECOME MORE ANTICYCLONIC. THE WEEKEND LOOKS TO FEATURE PLENTY OF SUNSHINE AND SEASONABLE TEMPERATURES...AS A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT BECOMES ESTABLISHED ACROSS THE REGION. THE 00Z GFS IS ACTUALLY DEVELOPING SOME CONVECTION ON SUNDAY UNDERNEATH THE RIDGE...WHICH IN THE ABSENCE OF ANY SIGNIFICANT MOISTURE AND INSTABILITY LOOKS RATHER SUSPECT. WILL LEAN TOWARD THE 00Z ECMWF WHICH IS INDICATING RAIN-FREE CONDITIONS UNDER THE RIDGE. QUIET WEATHER SHOULD CONTINUE INTO EARLY NEXT WEEK WITH THE RIDGE STILL EXPECTED TO BE IN PLACE ACROSS THE NORTHEAST CONUS. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... SATELLITE PICTURES SHOW RADIATION FOG IN MANY OF THE VALLEYS OF EASTERN NEW YORK AND WESTERN NEW ENGLAND. VARIOUS WEB CAMS AROUND THE AREA SHOW THE FOG STEADILY BURNING OFF. MOST OF THE FOG SHOULD BE GONE FROM THE TAF SITES BY 13Z EXCEPT KPSF WHERE IT MAY LINGER UNTIL 14Z. VFR CONDITIONS EXPECTED FOR MOST OF THE DAYLIGHT HOURS. A DISTURBANCE MOVING THROUGH COULD TRIGGER SCATTERED THUNDERSTORMS THIS AFTERNOON...SO HAVE PLACED VCSH IN ALL TAFS STARTING AROUND 19Z OR 20Z. THUNDERSTORMS COULD PRODUCE SOME MVFR AT TAF SITES BUT COVERAGE IS NOT EXPECTED TO BE WIDESPREAD ENOUGH TO PUT THUNDERSTORMS IN THE TAFS. THESE STORMS SHOULD DISSIPATE AFTER SUNSET...WITH SOME PATCHY VALLEY FOG RETURNING WEDNESDAY MORNING. WINDS ARE FORECAST TO BE FROM THE WEST TODAY AND TONIGHT AT 5 TO 15 KNOTS. OUTLOOK... WEDNESDAY NIGHT: SLIGHT CHANCE OF SHRA. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA ON TUESDAY AND WEDNESDAY BEFORE CLEARING THE REGION. MINIMUM RELATIVE HUMIDITIES THIS AFTERNOON AND TOMORROW AFTERNOON SHOULD RANGE IN THE 40 TO 55 PERCENT RANGE. NIGHTTIME RH VALUES SHOULD BE 70 TO 100 PERCENT. WINDS WILL BE WEST TO NORTHWEST AT 15 MPH OR LESS THROUGH THE PERIOD. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED EACH AFTERNOON AND EVENING THROUGH WEDNESDAY ASSOCIATED WITH AN ADVANCING COLD FRONT. THE THREAT OF ISOLATED FLOODING OF POOR DRAINAGE AND URBAN AREAS WILL CONTINUE THIS AFTERNOON THROUGH WEDNESDAY... MAINLY IF THUNDERSTORMS REPEATEDLY PASS OVER THE SAME LOCATIONS. DUE TO THE CONVECTIVE NATURE OF THE RAINFALL...MOST RIVER BASINS WILL NOT EXPERIENCE MUCH IMPACT. SOME RISES MAY OCCUR FOR AREAS THAT SEE REPEATED RAINFALL THROUGH MIDWEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...NAS NEAR TERM...SND/HWJIV/IRL SHORT TERM...NAS LONG TERM...JPV AVIATION...SND/JPV FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS TAUNTON MA
1112 AM EDT TUE AUG 5 2014 .SYNOPSIS... SCATTERED SHOWERS AND THUNDERSTORMS ARE ANTICIPATED LATE TODAY AND AGAIN ON WEDNESDAY AS HURRICANE BERTHA PASSES WELL OFFSHORE OF NEW ENGLAND WITH LITTLE IMPACT OTHER THAN HIGH SURF AND DANGEROUS RIP CURRENTS. A COLD FRONT WILL MOVE OFFSHORE WEDNESDAY NIGHT. ASIDE FROM A FEW SHOWERS THURSDAY AND FRIDAY AFTERNOON...HIGH PRESSURE BRINGS DRY WEATHER INTO THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1050 AM UPDATE... MONITORING BOTH KENX AND KOKX RADARS...SAW A LONELY SHOWER MOVE ACROSS CENTRAL VT INTO CENTRAL NH BEFORE DISSIPATING AROUND 14Z. ALSO SEE A BAND OF CUMULUS CLOUDS FORMING ALONG DEVELOPING SEA BREEZE FRONT ACROSS S CT ON LATEST VISIBLE SATELLITE LOOP. WILL CONTINUE TO MONITOR RADAR FOR SHOWER DEVELOPMENT...IF IT OCCURS DURING THE EARLY AFTERNOON. NOTING LATEST HRRR FORECAST RADAR TRENDS INDICATING ISOLD SHOWERS ACROSS S NH/N MA AND POSSIBLY ALONG SEA BREEZE FRONT ACROSS S CT...BUT AGAIN WILL MONITOR. TEMPS HAVE RISEN STEADILY SINCE SUNRISE...WITH READINGS IN THE 70S TO LOWER 80S AT 15Z...UP TO 84 AT KFIT. TEMPS/DEWPTS WERE CLOSE TO FORECASTED TRENDS. HAVE UPDATED GRIDS TO BRING CONDITIONS CURRENT. PREVIOUS DISCUSSION... BERTHA TO THE SE WHILE A BROAD-TROUGH SWEEPS ACROSS THE GREAT LAKES. PREVAILING SUBSIDENCE/DRY AIR /H85-H3/ BETWEEN THE TWO COLLOCATED WITH THE LEFT-ENTRANCE REGION OF THE H3 JET SHOULD RESULT IN QUIET WEATHER ACROSS S NEW ENGLAND INTO AFTERNOON. BUT WITH THE WESTERN APPROACH OF A COLD FRONT ASSOCIATED WITH THE BROAD H5 TROUGH...EXPECT THE INCREASE OF CYCLONIC FLOW AND ENHANCED ASCENT ALLOWING THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS OVER W MA / CT AND SW NH. COULD ALSO SEE ACTIVITY ASSOCIATED WITH LOCALIZED CONVERGENCE ALONG SEA-BREEZE BOUNDARIES. CONSIDERING INSTABILITY OF AROUND 1000 J/KG ALONG WITH 30 KTS OF BULK SHEAR...ORDINARY TO MULTI-CELLULAR CONVECTION IS ANTICIPATED. NOTING FORECAST SOUNDINGS WITH FREEZING LEVELS AROUND 10 KFT ALONG WITH A COMBINATION OF THIN-CAPE AND POTENTIAL INVERTED-V PROFILES... FEEL THERE IS AN ISOLATED THREAT OF HEAVY RAIN...STRONG TO DAMAGING WINDS...AND SMALL HAIL /IN PRIORITY OF CONCERN/. WARM AND HUMID CONDITIONS CONTINUING AS TEMPERATURES WARM TO AROUND THE MID-80S WITH DEWPOINTS RANGING AROUND THE MID-60S. COOLER ALONG THE SHORELINES WITH ANTICIPATED SEA-BREEZES. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... TONIGHT... COLD FRONTAL BOUNDARY CONTINUES TO SWEEP INTO S NEW ENGLAND. EXPECT SCATTERED SHOWER / THUNDERSTORM ACTIVITY...STRONGEST OF WHICH WILL CONTINUE TO BE ACROSS N/W INTERIOR...WEAKENING OVER TIME WITH THE LACK OF DAY-TIME HEATING AND INSTABILITY. FALLING HEIGHTS / CYCLONIC FLOW MAY PROLONG SHOWER ACTIVITY TILL AFTER MIDNIGHT AND TOWARDS THE COASTLINES. OTHERWISE...SOUPY AIR WITH DEWPOINTS AROUND THE MID-60S MAINTAINED BY SW FLOW WILL LIKELY RESULT IN ANOTHER NIGHT OF LOW-CLOUDS AND DENSE FOG FOR PORTIONS OF S/SE NEW ENGLAND ESPECIALLY ALONG THE SHORELINES. DRIER AIR BUILDING IN BEHIND THE FRONT SHOULD KEEP AREAS OF THE N/W INTERIOR FOG-FREE. LOWS NW-SE RANGING FROM THE LOW-60S TO UPPER-60S. WEDNESDAY... SYNOPTICALLY...IGNORE THE PRESSURE PATTERN. BELIEVE THE OVERNIGHT COLD FRONT BECOMES DIFFUSE AS A BROAD AREA OF LOW PRESSURE SITUATED MAINLY ACROSS SE NEW ENGLAND. AS THE MAIN CRUX OF ENERGY SWEEPS THROUGH THE PREVAILING MID-LEVEL BROAD TROUGH...FALLING HEIGHTS ARE INVOKED THROUGHOUT THE ATMOSPHERIC COLUMN. THE COMBINATION OF THE LEFT-FRONT-QUADRANT ASSOCIATED WITH THE H3 CYCLONIC JET...MID- LEVEL ENHANCED ASCENT...AND LOCALIZED CONVERGENCE OF A SOUPY UNSTABLE AIRMASS ALONG SEA-BREEZE BOUNDARIES...DEEP-LAYER ASCENT PREVAILS. ANTICIPATE SCATTERED SHOWER AND THUNDERSTORM ACTIVITY MAINLY ACROSS S/E INTERIOR NEW ENGLAND INCORPORATING E MA AND RI. ASSUMING INSTABILITY VALUES AROUND 1000 J/KG WILL BE MET IN AN ENVIRONMENT OF AVERAGE 30 KT W-E UNI-DIRECTIONAL SHEAR SHOULD YIELD ORDINARY TO MULTI-CELLULAR CONVECTION ALONG THE SEA-BREEZE BOUNDARIES. PWATS RANGE 1.0 - 1.5 INCHES. ONCE AGAIN...NOTING FORECAST SOUNDINGS WITH FREEZING LEVELS AROUND 10 KFT ALONG WITH A COMBINATION OF THIN-CAPE AND POTENTIAL INVERTED-V PROFILES...FEEL THERE IS AN ISOLATED THREAT OF HEAVY RAIN...STRONG TO DAMAGING WINDS...AND SMALL HAIL /IN PRIORITY OF CONCERN/. A GREATER THREAT OF URBAN FLOODING IS CERTAINLY PLAUSIBLE SHOULD STORMS PERPETUATE ALONG THE SEA-BREEZE. WARM AND MUGGY CONDITIONS EXPECTED MORE S/E WITH HIGHS AROUND THE UPPER-70S. COOLER AND DRIER N/W THOUGH LOW-80S POSSIBLE OVER THE LOWER CT-VALLEY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... OVERVIEW AND MODEL PREFERENCES... 05.00Z MODEL GUIDANCE ACTUALLY HAS FAIRLY GOOD AGREEMENT THROUGH MUCH OF THE LONG TERM IN SPITE OF THE FACT CONDITIONS FAVOR A FAIRLY AMPLIFIED FLOW PATTERN INTO THE WEEKEND. BASE OF A LONGWAVE TROF WITH HEIGHTS NEARLY 3 STD DEVIATIONS BELOW NORMAL WILL BE MOVING ACROSS NEW ENGLAND THU. THANKFULLY THE ORIENTATION AND MOVEMENT WILL BE ENOUGH TO FORCE BOTH THE REMNANTS OF BERTHA AND ITS MOISTURE WELL E OF NEW ENGLAND...ALLOWING THE DRIER AIR FROM RIDGING ACROSS THE GREAT LAKES INTO NEW ENGLAND INSTEAD. FOLLOWING THIS TROF...THE MID LVL RIDGE WILL THEN HOLD FAST ACROSS MUCH OF THE N CONUS AS DEEPENING TROF DEVELOPS ACROSS THE CANADIAN PRAIRIE INTO THE LATE WEEKEND AND EARLY NEXT WEEK. WITH THIS REASONABLY GOOD AGREEMENT...A BLEND OF LONG RANGE GUIDANCE WILL BE USED AS A BASELINE FOR THIS UPDATE. DETAILS... THU INTO FRI... ALTHOUGH SFC COLD FRONT WILL CONTINUE TO MOVE OFFSHORE DURING THE DAY THU...ACUTE VORT MAX WILL PIVOT ACROSS THE REGION DURING THE DAYLIGHT HOURS...AND LINGERING INTO FRI. THIS IS ASSOCIATED WITH VERY LOW H5 HEIGHTS AND TEMPS APPROACHING -18C. THEREFORE...WITH A FOCUS FOR LIFT AND SOME MID LVL DESTABILIZATION /MU CAPE VALUES MAY REACH AROUND 500J/KG IN SPOTS ON THU...SLIGHTLY LOWER ON FRI/ MAY SEE DIURNALLY DRIVEN SHOWERS AND POSSIBLY EVEN AN ISOLATED RUMBLE OF THUNDER. AT THE VERY LEAST LIKELY TO SEE A DECK OF SCT-BKN CU FOR EACH AFTERNOON AND EARLY EVENING. WITH SOME DRIER AIR THROUGH THE COLUMN STABILIZING THE AIRMASS FRI...WILL FEATURE HIGHER CHANCE POPS ON THU THAN FRI. GIVEN THE COOL TEMPS ALOFT AND FAIR AMOUNT OF DIURNAL CLOUD COVER...EXPECT TEMPS TO BE MAINLY BELOW NORMAL. HIGHS IN THE MID 70S...LOWS DIPPING INTO THE 50S IN SPOTS...LOW 60S IN NORMAL URBAN HEAT ISLANDS. THIS COMING WEEKEND... MID LVL RIDGE WILL BE SLOWLY MOVING IN FROM THE GREAT LAKES REGION. ATTENDANT HIGH PRES WILL MOVE ACROSS MUCH OF NEW ENGLAND THROUGH THE WEEKEND. +12C H85 TEMPS ON SAT FOLLOWED BY +14C ON SUN SUGGESTS TEMPS NEAR NORMAL ON SAT /HIGHS AROUND 80-LOW 80S/ AND SOMEWHAT ABOVE NORMAL SUN /HIGHS IN THE MID 80S/. MON INTO TUE... SOME DISAGREEMENT BEGINS TO SHOW HERE...MAINLY WITH THE TIMING AND DEPTH OF A LONGWAVE TROF MOVING E FROM THE CANADIAN PRAIRIE. AT THIS POINT IT LOOKS LIKE THE MID LVL RIDGE HAS HIGH ENOUGH HEIGHTS THAT IT SHOULD HOLD AS THE TROF DEEPENS TO KEEP AN PRECIP FROM A SLOWLY LIFTING WARM FRONT WELL TO THE S. WILL MAINTAIN A MOSTLY DRY FORECAST...BUT GIVEN THERE IS A PATTERN SHIFT AFOOT...WILL HAVE TO MONITOR THE TRENDS AS WEE GO THROUGH WEEK. THE E SHIFT IN THE SFC HIGH PRES SUGGESTS RETURN FLOW WITH INCREASING TEMPS AND HUMIDITY EACH DAY. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THROUGH WEDNESDAY... THIS AFTERNOON...MODERATE CONFIDENCE. EXPECT MAINLY VFR ACROSS MOST AREAS...BUT LOCAL MVFR-IFR MAY LINGER ACROSS KACK THROUGH 18Z OR SO. SOME ISOLD -SHRA/TSRA POSSIBLE...ESPECIALLY INTERIOR TERMINALS. WINDS MAINLY W-SW. SEA BREEZES FOR COASTAL TERMINALS. TONIGHT...MODERATE CONFIDENCE. SHRA/TSRA DISSIPATING AROUND 3Z ACROSS INTERIOR S NEW ENGLAND. WILL SEE THE RETURN OF MVFR-VLIFR CIGS/VSBYS...MAINLY FOR S/E NEW ENGLAND COASTLINES. WEDNESDAY... MVFR-VLIFR CIGS/VSBYS DISSIPATE. SEA-BREEZES AROUND 15Z BECOME THE FOCUS FOR SHRA/TSRA ACROSS INTERIOR E/SE MA AND ALL OF RI. ACTIVITY FURTHER W POSSIBLE. KBOS TERMINAL...MODERATE CONFIDENCE. LIGHT SEA BREEZE THROUGH 22Z-23Z. KBDL TERMINAL...HIGH CONFIDENCE. OUTLOOK...WED NIGHT THROUGH SATURDAY... WED NIGHT...MODERATE CONFIDENCE. SOME MIXED MVFR CONDITIONS IN FOG AND SHOWERS DURING THE EVENING GIVES WAY TO SOME IMPROVEMENT EARLY THU MORNING. THU INTO SAT...HIGH CONFIDENCE. MAINLY VFR...BUT THU AND FRI A BRIEF MVFR PERIOD IS POSSIBLE IN AFTERNOON SHOWERS OR AN ISOLATED THUNDERSTORMS. && .MARINE... FORECASTER CONFIDENCE LEVELS... LOW...LESS THAN 30 PERCENT. MODERATE...30 TO 60 PERCENT. HIGH...GREATER THAN 60 PERCENT. SHORT TERM...THIS AFTERNOON THROUGH WEDNESDAY... SWELLS WILL INCREASE AS BERTHA MAKES ITS CLOSEST APPROACH LATE TONIGHT. THIS WILL LEND TO INCREASING WAVE HEIGHTS ACROSS THE S/SE WATERS. SMALL CRAFT ADVISORIES FOR HAZARDOUS SEAS ISSUED ACCORDINGLY WITH WAVE HEIGHTS UP TO 7 FEET POSSIBLE. THE DELAY IN SWELL AND LIGHT WINDS FOR TODAY WILL LIMIT THE RIP CURRENT RISK...BUT WILL NEED TO WATCH FOR POTENTIAL HAZARDS TONIGHT INTO WEDNESDAY. LOW CLOUDS AND FOG WILL RETURN LATE TONIGHT INTO WEDNESDAY MORNING...WITH VSBYS AGAIN BELOW 1SM IN SOME AREAS MAINLY S COAST...CAPE COD AND THE ISLANDS. OUTLOOK...WED NIGHT THROUGH SATURDAY... WED NIGHT INTO THU...HIGH CONFIDENCE. ANY SHOWERS ASSOCIATED WITH A COLD FRONT WILL MOVE FURTHER OFFSHORE OVERNIGHT WED NIGHT. OTHERWISE...LINGERING 5-6 FT SWELL FROM BERTHA WILL BE GRADUALLY DIMINISHING INTO THE DAY ON THU. THEREFORE...SMALL CRAFT ADVISORIES ARE LIKELY TO LINGER INTO THU AS THE SWELL SUBSIDES. FRI AND SAT...HIGH CONFIDENCE. A PERIOD OF MAINLY QUIET BOATING WEATHER IS EXPECTED AS HIGH PRES MOVES OVER THE WATERS. && .BOX WATCHES/WARNINGS/ADVISORIES... CT...NONE. MA...NONE. NH...NONE. RI...NONE. MARINE...SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM MIDNIGHT TONIGHT TO 6 PM EDT WEDNESDAY FOR ANZ235-237-254>256. && $$ SYNOPSIS...DOODY/SIPPRELL NEAR TERM...DOODY/SIPPRELL/EVT SHORT TERM...SIPPRELL LONG TERM...DOODY AVIATION...DOODY/SIPPRELL/EVT MARINE...DOODY/SIPPRELL/EVT
AREA FORECAST DISCUSSION
NWS ALBANY NY
1047 AM EDT TUE AUG 5 2014 .SYNOPSIS... PARTLY SUNNY AND WARM WEATHER IS EXPECTED TODAY. A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA LATER TODAY AND WEDNESDAY BEFORE CLEARING THE REGION. COOL AND BREEZY WEATHER...WITH A CONTINUED THREAT OF AFTERNOON SHOWERS...IS FORECAST FOR THURSDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1045 AM EDT...CURRENT FORECAST LOOKS ON TRACK WITH ONLY MINOR TWEAKS TO THE FORECAST TO ACCOUNT FOR SKY COVER AND TEMPS AS ANOTHER MUGGY AND WARM DAY IS IN STORE FOR THE REGION. WITH THE DISSIPATION OF THE EARLY MORNING FOG...MUCH OF THE FORECAST AREA REMAINS MOSTLY SUNNY THIS MORNING WITH CU NOW BEGINNING TO DEVELOP ACROSS THE HIGHER TERRAIN. WITH STRONG DAYTIME HEATING EXPECTED...TEMPS SHOULD REACH INTO THE MID AND UPPER 80S ACROSS MUCH OF THE REGION EXCEPT FOR UPPER 70S TO LOW 80S ACROSS THE SOUTHERN ADIRONDACKS. COMBINED WITH DEWPOINTS IN THE LOW TO MID 60S AND MARGINAL MIDLEVEL LAPSE RATES AROUND 6.0 C/KM...AROUND 500-1500 J/KG OF SBCAPE IS EXPECTED BY MID AFTERNOON. THERE WILL BE LITTLE IN THE WAY OF DYNAMIC FORCING ACROSS THE REGION...AS A COLD FRONT REMAINS FAR ENOUGH NORTH AND WEST TO ALLOW FOR LOCAL TOPOGRAPHIC/DIFFERENTIAL HEATING BOUNDARIES TO BE THE PRIMARY FOCUS FOR CONVECTION. THE HRRR DEPICTS WIDELY SCATTERED TO SCATTERED SHOWERS AND THUNDERSTORMS DEVELOPING BETWEEN 12PM-2PM...AND PERSISTING THROUGH MUCH OF THE AFTERNOON BEFORE A DECAYING CLUSTER OF STORMS CURRENTLY ACROSS THE LOWER GREAT LAKES REACHES THE REGION BY THE LATE EVENING HOURS. ALTHOUGH THERE WILL BE MODEST INSTABILITY IN PLACE...MEAGER DYNAMIC FORCING WILL RESULT IN MAINLY GENERIC THUNDERSTORM ACTIVITY WITH THE STRONGEST STORMS CAPABLE OF BRIEF HEAVY DOWNPOURS THAT MAY PRODUCE LOCALIZED PONDING OF WATER ON ROADWAYS AS WELL AS IN LOW LYING AND URBAN AREAS. HAVE ONLY GONE WITH SLIGHT CHANCE AND CHANCE POPS AS COVERAGE WILL BE SCATTERED AT BEST. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/... ANY LINGERING SHOWERS OR THUNDERSTORMS SHOULD DISSIPATE THROUGH THE EVENING...WITH INTERVALS OF CLOUDS THE REST OF THE NIGHT. THE BETTER UPPER DYNAMICS ASSOCIATED WITH THE UPPER SYSTEM...AND THE BETTER LOW LEVEL FORCING ALONG A TIGHTENING AND ADVANCING BOUNDARY LAYER THERMAL GRADIENT SHOULD SUPPORT SCATTERED SHOWERS AND THUNDERSTORMS WEDNESDAY...MAINLY AFTERNOON AND EVENING. HIGHS WEDNESDAY IN THE MID 70S TO LOWER 80S. ONE LAST LINGERING PIECE OF UPPER ENERGY AND THE UPPER COLD POOL BRUSH JUST NORTH AND NORTHEAST OF OUR REGION THURSDAY SUPPORTING ONE LAST ROUND OF ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS...MAINLY IN NORTHERN AND EASTERN AREAS. COOLING CONTINUES TO TAKE PLACE ACROSS THE REGION...AND HIGHS SHOULD BE IN THE 70S TO NEAR 80. NIGHTTIME LOWS TONIGHT SHOULD BE IN THE UPPER 50S TO LOWER 60S...COOLER IN HIGHER TERRAIN. FOR WEDNESDAY NIGHT AND THURSDAY NIGHT LOWS IN THE 50S WITH AROUND 50 HIGHER TERRAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... FRIDAY WE WILL DEALING WITH THE LAST VESTIGES OF A CYCLONIC FLOW REGIME...WITH POTENTIALLY ONE FINAL WEAK DISTURBANCE ROTATING AROUND THE WESTERN PERIPHERY OF AN UPPER LOW OVER THE CANADIAN MARITIMES. SO WILL MENTION JUST SLIGHT CHANCE POPS FOR WESTERN NEW ENGLAND...BEFORE TRANQUIL CONDITIONS DEVELOP FRIDAY NIGHT AS THE FLOW STARTS TO BECOME MORE ANTICYCLONIC. THE WEEKEND LOOKS TO FEATURE PLENTY OF SUNSHINE AND SEASONABLE TEMPERATURES...AS A RIDGE OF HIGH PRESSURE BOTH AT THE SURFACE AND ALOFT BECOMES ESTABLISHED ACROSS THE REGION. THE 00Z GFS IS ACTUALLY DEVELOPING SOME CONVECTION ON SUNDAY UNDERNEATH THE RIDGE...WHICH IN THE ABSENCE OF ANY SIGNIFICANT MOISTURE AND INSTABILITY LOOKS RATHER SUSPECT. WILL LEAN TOWARD THE 00Z ECMWF WHICH IS INDICATING RAIN-FREE CONDITIONS UNDER THE RIDGE. QUIET WEATHER SHOULD CONTINUE INTO EARLY NEXT WEEK WITH THE RIDGE STILL EXPECTED TO BE IN PLACE ACROSS THE NORTHEAST CONUS. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... SATELLITE PICTURES SHOW RADIATION FOG IN MANY OF THE VALLEYS OF EASTERN NEW YORK AND WESTERN NEW ENGLAND. VARIOUS WEB CAMS AROUND THE AREA SHOW THE FOG STEADILY BURNING OFF. MOST OF THE FOG SHOULD BE GONE FROM THE TAF SITES BY 13Z EXCEPT KPSF WHERE IT MAY LINGER UNTIL 14Z. VFR CONDITIONS EXPECTED FOR MOST OF THE DAYLIGHT HOURS. A DISTURBANCE MOVING THROUGH COULD TRIGGER SCATTERED THUNDERSTORMS THIS AFTERNOON...SO HAVE PLACED VCSH IN ALL TAFS STARTING AROUND 19Z OR 20Z. THUNDERSTORMS COULD PRODUCE SOME MVFR AT TAF SITES BUT COVERAGE IS NOT EXPECTED TO BE WIDESPREAD ENOUGH TO PUT THUNDERSTORMS IN THE TAFS. THESE STORMS SHOULD DISSIPATE AFTER SUNSET...WITH SOME PATCHY VALLEY FOG RETURNING WEDNESDAY MORNING. WINDS ARE FORECAST TO BE FROM THE WEST TODAY AND TONIGHT AT 5 TO 15 KNOTS. OUTLOOK... WEDNESDAY NIGHT: SLIGHT CHANCE OF SHRA. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A SLOW MOVING COLD FRONT APPROACHING FROM SOUTHERN CANADA WILL BRING A CHANCE FOR THUNDERSTORMS ACROSS MUCH OF THE AREA ON TUESDAY AND WEDNESDAY BEFORE CLEARING THE REGION. MINIMUM RELATIVE HUMIDITIES THIS AFTERNOON AND TOMORROW AFTERNOON SHOULD RANGE IN THE 40 TO 55 PERCENT RANGE. NIGHTTIME RH VALUES SHOULD BE 70 TO 100 PERCENT. WINDS WILL BE WEST TO NORTHWEST AT 15 MPH OR LESS THROUGH THE PERIOD. && .HYDROLOGY... SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED EACH AFTERNOON AND EVENING THROUGH WEDNESDAY ASSOCIATED WITH AN ADVANCING COLD FRONT. THE THREAT OF ISOLATED FLOODING OF POOR DRAINAGE AND URBAN AREAS WILL CONTINUE THIS AFTERNOON THROUGH WEDNESDAY... MAINLY IF THUNDERSTORMS REPEATEDLY PASS OVER THE SAME LOCATIONS. DUE TO THE CONVECTIVE NATURE OF THE RAINFALL...MOST RIVER BASINS WILL NOT EXPERIENCE MUCH IMPACT. SOME RISES MAY OCCUR FOR AREAS THAT SEE REPEATED RAINFALL THROUGH MIDWEEK. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...NAS NEAR TERM...SND/IRL SHORT TERM...NAS LONG TERM...JPV AVIATION...SND/JPV FIRE WEATHER...NAS HYDROLOGY...NAS
AREA FORECAST DISCUSSION
NWS MIAMI FL
201 AM EDT TUE AUG 5 2014 .AVIATION... MID AND HIGH CLOUDS REMAIN WITH AN AREA OF LIGHT RAIN NEARING TMB. OTHERWISE THE REST OF THE NIGHT SHOULD REMAIN QUIET WITH CANOPY OF MID/HIGH CLOUDS CONTINUING TO STREAM NORTH FROM THE KEYS. QUESTIONABLE AS TO HOW MUCH THESE CLOUDS EFFECT TIMING OF ACTIVITY TUESDAY. WESTERLY FLOW TOMORROW MEANS EARLIER SHOWERS AND STORMS AT KAPF PROGRESSING ACROSS THE PENINSULA TO THE EAST COAST IN THE AFTERNOON WITH VCTS AT ALL SITES. AREA OF LOW PRESSURE/SURFACE TROUGH WILL HAVE DEPARTED NORTHEAST BY THE END OF THE DAY. DEEP MOISTURE REMAINS WITH SOME STORMS PRODUCING BRIEF IFR POSSIBLY AT ALL TAF SITES TODAY. STORMS SHOULD END QUICKLY THIS EVENING. && .PREV DISCUSSION... /ISSUED 948 PM EDT MON AUG 4 2014/ UPDATE... ALTHOUGH CONDITIONS HAVE IMPROVED, THE LOW THAT BROUGHT THE SHOWERS AND THUNDERSTORMS TO SOUTH FLORIDA EARLIER TODAY STILL HAS THE POTENTIAL TO BRING ADDITIONAL PRECIP TO THE AREA. THE GULF COAST STILL LOOKS TO BE THE AREA TO HAVE THE BEST CHANCES, ALTHOUGH MUCH LIGHTER ACCUMULATIONS THAN EARLIER. THE EAST COAST OF SOUTH FLORIDA, AS WELL AS THE ATLANTIC WATERS, MAY SEE SOME SCATTERED SHOWERS DEVELOP THIS EVENING. THE HRRR STILL SHOWS THE POSSIBILITY OF SHOWERS, ALTHOUGH THE GFS AND ECMWF TEND TO KEEP ANY PRECIP ALONG THE COASTAL AREAS. GIVEN THE UNCERTAINTY, HAVE KEPT SCATTERED POPS IN THE FORECAST FOR NOW. PREV DISCUSSION... /ISSUED 740 PM EDT MON AUG 4 2014/ AVIATION... DEBRIS CLOUD FIELD FROM LARGE CONVECTIVE COMPLEX WILL GRADUALLY IMPROVE THROUGH THE NIGHT WITH VFR CONDITIONS EXPECTED AT ALL TERMINALS. ABUNDANT MOISTURE TO CONTINUE THROUGH TUESDAY WITH INCREASING THREAT FOR CLOUDS AND TSRA AFT 14-16Z WITH THE GREATEST PROBABILITY NEAR KPBI SO PLACED A PROB30 GROUP IN THEIR TAF FOR THE AFTERNOON. SURFACE WIND WILL BE L/V BECMG SW AT 5-10 KT AFT 14Z ALL SITES. KOB PREV DISCUSSION... /ISSUED 312 PM EDT MON AUG 4 2014/ DISCUSSION... LATEST SURFACE ANALYSIS MAP SHOWS A SURFACE TROUGH AXIS EXTENDING FROM NORTHEASTERN FLORIDA THROUGH COLLIER COUNTY`S COASTLINE. SHOWERS AND THUNDERSTORMS WILL CONTINUE TONIGHT AS THE LOW PRESSURE LOCATED ACROSS NORTHEASTERN FLORIDA PREVAILS. SOUTHERLY SURFACE FLOW WILL CONTINUE ACROSS SOUTH FLORIDA THROUGH AT LEAST THE MIDDLE OF THE WEEK. MOISTURE WILL CONTINUE ABUNDANT AND WARM TEMPERATURES WILL PREVAIL ACROSS THE PENINSULA THROUGH THIS PERIOD. WIND FLOW WILL THEN BECOME WEAK AS HIGH PRESSURE BUILDS ACROSS THE AREA BY WEDNESDAY. WIND FLOW WILL BECOME EASTERLY AND AFTERNOON SHOWERS AND THUNDERSTORMS WILL THEN PREVAIL FROM THAT POINT THROUGH THE WEEKEND AS BOTH COASTS SEA BREEZES DEVELOP AND INTERACT ACROSS THE LAKE REGION. MARINE... BERTHA WILL CONTINUE MOVING NORTH AND AWAY FROM THE BAHAMAS. SOUTHERLY WINDS ARE FORECAST TO REMAIN AROUND 5-15 KTS THROUGH AT LEAST WEDNESDAY. WEAKER WINDS WILL RETURN BY MID WEEK BEFORE A GENERAL SSE TO S FLOW IS PREVALENT BY THE END OF THE WEEK AND THIS WEEKEND. SCATTERED SHOWERS AND STORMS COULD LEAD TO GUSTY WINDS AND LOCALLY CHOPPIER CONDITIONS EACH DAY ALONG WITH REDUCED VISIBILITIES. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 91 76 90 77 / 60 30 40 30 FORT LAUDERDALE 91 78 92 79 / 50 20 40 30 MIAMI 92 78 91 78 / 50 20 40 30 NAPLES 90 77 90 77 / 50 20 40 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...84/AK LONG TERM....84/AK AVIATION...21/KM
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
345 AM EDT TUE AUG 5 2014 .SYNOPSIS... DRIER AIR WILL ENTER THE REGION FROM THE WEST TODAY AND WEDNESDAY PROVIDING WARMER AND DRIER WEATHER. UNSETTLED WEATHER WILL RETURN FOR THE WEEKEND ASSOCIATED WITH A FRONTAL SYSTEM. && .NEAR TERM /THROUGH TONIGHT/... SURFACE LOW PRESSURE OFF THE SOUTHEAST COAST HAS BEEN SHOWING SIGNS OF DEEPENING A BIT AND GRADUALLY LIFTING NORTHWARD OVER THE PAST 6 HRS WHILE THE UPPER TROUGH AXIS REMAINS TO THE WEST OVER THE OHIO/TENNESSEE VALLEYS. WEAK SHORTWAVE ENERGY WILL LIFT NORTHEAST ACROSS THE FORECAST AREA THIS MORNING THEN SHIFT OFF TO THE NORTHEAST WITH NVA DEVELOPING ACROSS THE AREA BY LATE AFTERNOON. FORECAST SOUNDINGS INDICATE DEVELOPING MID LEVEL CAPPING INVERSION WHICH SHOULD LIMIT CONVECTION AND PREVENT SEVERE THREAT. WEAK TO MODERATE INSTABILITY AND BETTER MOISTURE CONFINED TO THE EAST AND SOUTHEAST PARTS OF THE FORECAST AREA. ISOLATED SHOWERS OR THUNDERSTORMS POSSIBLE ACROSS THE EASTERN MIDLANDS. THE MAIN CONVERGENCE ASSOCIATED WITH THE NORTHWARD LIFTING SURFACE LOW ARE EXPECTED TO REMAIN ALONG AND OFF THE COAST. TEMPERATURES WILL AGAIN BE WARM TODAY AROUND 90 TO THE LOWER 90S. DRY WEATHER IS EXPECTED TONIGHT UNDER CLEARING SKIES WITH OVERNIGHT LOWS IN THE UPPER 60S TO AROUND 70. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... UPPER TROUGH AXIS SHIFTS EAST OF THE REGION BY WEDNESDAY ALLOWING BROAD WEST TO NORTHWESTERLY FLOW TO MOVE OVER THE FORECAST AREA...RESULTING IN DRIER AND WARMER AIR TO SETTLE OVER THE REGION AIDED BY WEAK DOWNSLOPING FLOW. A CAPPING MID LEVEL INVERSION AND PWAT VALUES BELOW 1.5 INCHES AND WEAK INSTABILITY WILL PROVIDE DRY WEATHER FOR WEDNESDAY AS TEMPERATURES CLIMB ABOVE NORMAL INTO THE MID 90S. THE UPPER PATTERN WILL BEGIN TO SHIFT THURSDAY AS ANOTHER UPPER TROUGH TRIES TO TAKE HOLD ACROSS THE EASTERN UNITED STATES. THIS WILL HELP DRIVE A COLD FRONT TOWARDS THE AREA THURSDAY. MOISTURE INCREASES WITH PWAT VALUES CLIMBING BACK TO NEAR 1.7 INCHES AND DAYTIME HEATING SHOULD SUPPORT ISOLATED CONVECTION. COMPRESSIONAL HEATING AHEAD OF THE FRONT THURSDAY WILL YIELD WARM TEMPERATURES IN THE MID TO UPPER 90S. THE FRONT SHOULD SLOW DOWN AND STALL ACROSS THE FORECAST AREA THURSDAY NIGHT. && .LONG TERM /FRIDAY THROUGH MONDAY/... UNSETTLED WEATHER RETURNS TO THE REGION THIS WEEKEND WITH A STALLED FRONTAL BOUNDARY IN THE AREA AND WEAK UPPER TROUGHING ACROSS THE MID-ATLANTIC AND SOUTHEAST STATES. ATMOSPHERIC MOISTURE WILL INCREASE SIGNIFICANTLY BY FRIDAY AFTERNOON AS PWAT VALUES RISE ABOVE 2 INCHES AND REMAIN SO THROUGH THE REST OF THE EXTENDED PERIOD...REACHING AS HIGH AS 2.25-2.30 INCHES...WHICH IS APPROACHING THE 99TH PERCENTILE. SLOW STORM MOVEMENT AND VERY HIGH ATMOSPHERIC MOISTURE CONTENT WILL LEAD TO THE POSSIBILITY OF A HEAVY RAIN THREAT AND ISOLATED FLOODING. HIGH CHANCE POPS FRIDAY THROUGH SUNDAY THEN A BIT LOWER BY MONDAY AS THE TROUGH FLATTENS. TEMPERATURES THROUGH THE EXTENDED WILL BE BELOW NORMAL WITH HIGHS IN THE UPPER 80S FRIDAY THEN BACK INTO THE LOWER TO MID 80S SAT- MON. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... FRONT REMAINS STATIONARY NEAR THE COAST. WAVE OF LOW PRESSURE OFFSHORE THE S SC COAST WILL SHIFT NE TODAY. AN E TO NE LOW LEVEL FLOW AHEAD OF THE LOW OFF THE ATLANTIC MAY PROVIDE SOME LOW CLOUDINESS LATE TONIGHT INTO THIS MORNING. LATEST HRRR INDICATES SUCH...AND RECENT OBS NEAR THE EASTERN MIDLANDS INDICATING SOME DEVELOPING. WILL EXPECT IFR TO POSSIBLY LIFR CIGS AT THE TERMINALS LATER TONIGHT INTO THIS MORNING...WITH SOME QUESTIONS ON VSBYS. SOME DRIER AIR WILL ENTER THE REGION FROM THE WEST TODAY AS UPPER TROUGH AXIS SLOWLY SHIFTS EAST THROUGH OUR REGION. LIMITED MOISTURE EXPECTED TO PRECLUDE CONVECTION OVER MOST OF OUR FORECAST AREA TODAY. SOME AFTERNOON PRECIP POTENTIAL E/SE FORECAST AREA NEAR OGB...BUT WILL LEAVE OUT MENTION IN THE TAF DUE TO LOW CONFIDENCE. EXTENDED AVIATION OUTLOOK...DRIER AIR MOVING IN WILL REDUCE LATE NIGHT/EARLY MORNING FOG POTENTIAL...AND MAY BE RESTRICTED TO THE FOG PRONE SITES AGS AND OGB. SCATTERED DIURNAL CONVECTION RETURNS FRIDAY THROUGH SUNDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
118 AM EDT TUE AUG 5 2014 .SYNOPSIS... DRIER AIR WILL ENTER THE REGION FROM THE WEST TUESDAY AND WEDNESDAY PROVIDING WARMER AND DRIER WEATHER. UNSETTLED WEATHER WILL RETURN FOR THE WEEKEND ASSOCIATED WITH A FRONTAL SYSTEM. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... LOW PRESSURE OFF THE SOUTHEAST COAST WILL MOVE NORTH THROUGH TONIGHT. HOWEVER...MUCH OF THE CONVERGENCE ASSOCIATED WITH THE LOW PLUS THE DEEPER MOISTURE SHOULD STAY EAST OF THE FORECAST AREA. SCATTERED SHOWERS THAT MAINLY AFFECTED THE EAST PART OF THE AREA HAVE DISSIPATED WITH THE LOSS OF HEATING. THE LATEST HRRR DOES NOT INDICATE ADDITION SHOWERS OVERNIGHT. LOW-LEVEL MOISTURE AND DIURNAL COOLING SHOULD HELP SUPPORT STRATUS AND FOG DEVELOPMENT. MOST OF THE GFS AND NAM MOS PLUS SREF GUIDANCE INDICATE SOME FOG BUT THE FOG SHOULD BE LIMITED BY SOME CLOUDINESS AND INSTABILITY. THE LATEST HRRR INDICATES LITTLE FOG. WE FORECASTED PATCHY FOG. WE LEANED TOWARD THE WARMER TEMPERATURE GUIDANCE BECAUSE OF CLOUDINESS. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... THE MAIN UPPER TROUGH AXIS WILL SHIFT THROUGH THE REGION THROUGH THE DAY TUESDAY...FINALLY SHIFTING OFFSHORE BY TUESDAY NIGHT. THE MAIN UPPER FLOW WILL THEN FLATTEN OUT INTO WEDNESDAY...ALTHOUGH WINDS ALOFT WILL STILL BE MORE NORTHWESTERLY. WITH THIS PATTERN THE CHANCE FOR RAIN SHOULD BEGIN TO PUSH OFFSHORE THROUGH THE DAY TUESDAY AS DRIER AIR MOVES INTO THE REGION. THIS WILL LEAVE TUESDAY NIGHT THROUGH WEDNESDAY NIGHT DRY. THE MAIN UPPER PATTERN WILL THEN BEGIN TO SHIFT THURSDAY AS ANOTHER UPPER TROUGH TRIES TO TAKE HOLD ACROSS THE EASTERN UNITED STATES. THIS WILL HELP DRIVE A COLD FRONT TOWARDS THE AREA THURSDAY...WHICH WILL ONCE AGAIN LEAD TO AN INCREASE IN RAIN CHANCES. THE FRONT SHOULD SLOW DOWN AND STALL ACROSS THE FORECAST AREA THURSDAY NIGHT. AS FOR TEMPERATURES...WITH DRIER AIR AND MORE SUNSHINE TUESDAY...WOULD EXPECT THAT THE AFTERNOON HIGHS WILL INCREASE BACK INTO THE UPPER 80S AND LOWER 90S TUESDAY...AND INTO THE LOWER TO MIDDLE 90S WEDNESDAY. WITH AN INCREASE IN CLOUDS AHEAD OF THE FRONT THURSDAY...TEMPERATURES WILL COOL SLIGHTLY...BUT SHOULD STILL REACH THE 90S. && .LONG TERM /FRIDAY THROUGH MONDAY/... THE COLD FRONT THAT WILL STALL ACROSS THE REGION FRIDAY SHOULD LINGER THROUGH THE WEEKEND. THE MAIN UPPER PATTER REMAINS OUT OF THE NORTHWEST. THE UPPER FLOW PATTERN WILL ALIGN WITH THE STALLED FRONT FROM SOUTHERN SC WESTWARD INTO THE SOUTHERN PLAINS STATES. WEATHER SYSTEMS THAT FORM WEST ALONG THIS FRONT MAY BE ABLE TO TRACK EASTWARD AND THROUGH THE SOUTHEASTERN STATES THROUGH THE PERIOD. WOULD EXPECT THAT CHANCE POPS SHOULD CONTINUE THROUGH THE WEEKEND AND INTO THE EARLY PART OF NEXT WEEK DUE TO THE SURFACE BOUNDARY...AND ENERGY ALOFT MOVING ALONG THIS FRONT TOWARDS THE EAST. PWATS BACK UP AROUND 2 INCHES THROUGH THE PERIOD WILL ALLOW FOR A HEAVY RAINFALL POTENTIAL. GFS BEGINS TO SHOW A SURFACE WEDGE FLOW PATTERN EAST OF THE APPALACHIANS BEGINNING SUNDAY INTO MONDAY...WHICH SHOULD BRING TEMPERATURES BACK DOWN INTO THE 80S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... FRONT REMAINS STATIONARY NEAR THE COAST. WAVE OF LOW PRESSURE OFFSHORE THE S SC COAST WILL SHIFT NE TODAY. AN E TO NE LOW LEVEL FLOW AHEAD OF THE LOW OFF THE ATLANTIC MAY PROVIDE SOME LOW CLOUDINESS LATE TONIGHT INTO THIS MORNING. LATEST HRRR INDICATES SUCH...AND RECENT OBS NEAR THE EASTERN MIDLANDS INDICATING SOME DEVELOPING. WILL EXPECT IFR TO POSSIBLY LIFR CIGS AT THE TERMINALS LATER TONIGHT INTO THIS MORNING...WITH SOME QUESTIONS ON VSBYS. SOME DRIER AIR WILL ENTER THE REGION FROM THE WEST TODAY AS UPPER TROUGH AXIS SLOWLY SHIFTS EAST THROUGH OUR REGION. LIMITED MOISTURE EXPECTED TO PRECLUDE CONVECTION OVER MOST OF OUR FORECAST AREA TODAY. SOME AFTERNOON PRECIP POTENTIAL E/SE FORECAST AREA NEAR OGB...BUT WILL LEAVE OUT MENTION IN THE TAF DUE TO LOW CONFIDENCE. EXTENDED AVIATION OUTLOOK...DRIER AIR MOVING IN WILL REDUCE LATE NIGHT/EARLY MORNING FOG POTENTIAL...AND MAY BE RESTRICTED TO THE FOG PRONE SITES AGS AND OGB. SCATTERED DIURNAL CONVECTION RETURNS FRIDAY THROUGH SUNDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
207 PM CDT TUE AUG 5 2014 .DISCUSSION... 1013 AM CDT NO BIG CHANGES TO GOING FORECAST FOR TODAY. VISIBLE SATELLITE IMAGERY SHOWS FAIRLY EXTENSIVE STRATUS ACROSS THE CWA THIS MORNING. THE HIGH SUN ANGLE AND LACK OF LOW LEVEL INVERSION TO TRAP THIS MOISTURE WOULD SUGGEST THAT IT SHOULD MIX OUT THIS AFTERNOON WITH AT LEAST PARTIAL CLEARING. GIVEN THE ANTICIPATED SUNSHINE MADE NO CHANGES TO GOING HIGH TEMP FORECAST FOR TODAY...BUT DID SLOW THE TEMP RISE IN THE HOURLY GRIDS INTO EARLY AFTERNOON DUE TO THE CLOUDINESS. ILL DEFINED COLD FRONT WILL CONTINUE SAG SLOWLY SOUTH ACROSS THE AREA THIS AFTERNOON...BUT LOW LEVEL CONVERGENCE ALONG THE FRONT WILL BE QUITE WEAK AND WATER VAPOR IMAGERY AND MODEL GUIDANCE DO NOT SHOW ANY UPSTREAM SHORTWAVES TO ENHANCE LARGE SCALE ASCENT. DESPITE THESE NEGATIVES...MODIFYING THE ILX 12Z SOUNDING FOR EXPECTED AFTERNOON CONDITIONS YIELDS SEVERAL HUNDRED JOULES OF MLCAPE WITH LITTLE INHIBITION...SO STILL POSSIBLE THAT ISOLATED SHRA/TSRA COULD DEVELOP OVER SOUTHEAST CWA THIS AFTERNOON. IZZI //PREV DISCUSSION... 355 AM CDT FORECAST CONCERNS FOCUS ON RAIN AND THUNDER CHANCES DIMINISHING FROM THE NORTH TODAY AS WEAK COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE FORECAST AREA...AND AGAIN WEDNESDAY INTO THURSDAY AS ANOTHER SHORT WAVE AND JET STREAK DIG SOUTHEAST ACROSS THE REGION. AREA OF RAIN/THUNDERSTORMS HAS PUSHED SOUTHEAST ACROSS THE FORECAST AREA SINCE YESTERDAY AFTERNOON IN ASSOCIATION WITH A WEAK COLD FRONT AND A DIGGING MID-LEVEL SHORT WAVE TROUGH. MOST OF THE RAIN WAS SOUTHEAST OF A PRINCETON ILLINOIS TO GARY INDIANA LINE AS OF 3 AM AND SHOULD CONTINUE TO FOCUS OVER THE SOUTHEAST THIRD OR SO OF THE CWA THIS MORNING AS THE MID-LEVEL WAVE AND AN EMBEDDED MCV PROPAGATE INTO INDIANA. HARD TO PLACE THE ACTUAL COLD FRONTAL BOUNDARY GIVEN LIGHT GRADIENT AND CONVECTIVE OUTFLOW CONTAMINATED SURFACE WIND FIELD...THOUGH IT APPEARS TO BE SOMEWHERE FROM NORTH OF KORD TO KDKB TO SOUTH OF KSQI IN LATEST SURFACE ANALYSIS. FRONT IS PROGGED TO CONTINUE TO DRIFT SOUTHEAST THIS MORNING BEHIND WEAK SURFACE WAVE WITH BEST POTENTIAL FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT LATER THIS MORNING AND THIS AFTERNOON TO BE ALONG/SOUTH OF THE FRONT ACROSS THE SOUTH/SOUTHEAST PART OF THE CWA. ALSO...WITH LITTLE PUSH TO THE FRONT AT THIS TIME...LOW STRATUS AND FOG WAS DEVELOPING INTO NORTHWEST AND NORTH CENTRAL IL...AND WILL LIKELY LINGER AFTER SUNRISE THIS MORNING. SOMEWHAT DRIER LOW LEVEL AIR WILL FILTER IN FROM THE NORTH BY TONIGHT AS HIGH PRESSURE SPREADS ACROSS THE NORTHERN GREAT LAKES REGION...AND THE FRONT MOVES INTO DOWNSTATE IL/IN. GUIDANCE IS IN GOOD AGREEMENT IN DIGGING ANOTHER SHORT WAVE ACROSS THE MIDWEST WEDNESDAY INTO THURSDAY HOWEVER...WITH OVERRUNNING OF THE LOW LEVEL FRONTAL ZONE DEVELOPING FROM NORTHWEST IOWA INTO CENTRAL ILLINOIS. MODEL TREND HAS BEEN TO DEVELOP FAIRLY STRONG FRONTOGENESIS ALONG THE ELEVATED BAROCLINIC ZONE BENEATH THE RIGHT ENTRANCE REGION OF A 90 KT UPPER JET STREAK THROUGH THURSDAY...BRINGING A COUPLE OF PERIODS OF RAIN AND THUNDERSTORMS BACK INTO THE FORECAST AREA FROM WEDNESDAY MORNING THROUGH THURSDAY NIGHT. THE POTENTIAL EXISTS FOR SOME LOCALLY HEAVY RAINFALL THURSDAY/THURSDAY NIGHT ACROSS SOUTHERN PARTS OF THE CWA...AS 2+ INCH PWATS SPREAD NORTH. GFS/WRF BOTH DELIVER MORE THAN AN INCH OF RAIN TO THE SOUTHERN CWA DURING THIS TIME. FRONTAL ZONE THEN SHIFTS SOUTH INTO THE OHIO VALLEY AS HIGH PRESSURE STRENGTHENS ACROSS THE NORTHERN GREAT LAKES REGION FRIDAY AND SATURDAY. EASTERLY LOW LEVEL FLOW AROUND THE HIGH FAVORS DRY WEATHER AND PREFER THE DRIER ECMWF SOLUTION FOR THIS PERIOD. ANOTHER UPPER TROUGH APPROACHES THE REGION BY MONDAY HOWEVER...WITH AN INCREASE IN RAIN CHANCES LATER SUNDAY INTO MONDAY. TEMPERATURES THROUGH THE FORECAST PERIOD WILL AVERAGE JUST A BIT BELOW NORMAL WITH THE COOLEST DAYS WEDNESDAY-THURSDAY REMAINING IN THE 70S. OTHERWISE AROUND 80/LOWER 80S APPEAR REASONABLE. SURFACE FLOW WILL BE OFF THE LAKE THROUGH MOST OF THE PERIOD KEEPING AREAS NEAR LAKE MICHIGAN A LITTLE COOLER. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * NORTHEAST WINDS INCREASING TO AROUND 10KT DURING THE MID- AFTERNOON. * TEMPORARY MVFR CIGS POSSIBLE EARLY THIS AFTERNOON. * FOG POSSIBLE AGAIN TONIGHT...MAINLY MVFR. * NORTHEAST WINDS AROUND 10 KT AGAIN WEDNESDAY AFTERNOON. //DISCUSSION...UPDATED 18Z... A VERY SLOW MOVING COOL FRONT IS DRAPED FROM NEAR STL TO GYY TO DET. LOW-LEVEL MOISTURE POOLED ALONG THIS WAS RESPONSIBLE FOR THE MORNING FOG AND LOW CLOUDS...WITH THE LATTER STILL CONTINUING AT A FEW AIRPORTS EARLY THIS AFTERNOON. CEILINGS SHOULD CONTINUE TO SLOWLY LIFT AND EVEN SCATTER BY LATER IN THE DAY. BEHIND THE FRONT...WINDS SLOWLY INCREASE FROM THE NORTHEAST. AN INCREASE IN WIND SPEEDS UP TO AROUND 10 KT CONTINUES TO BE ANTICIPATED AT CHICAGOLAND TAF SITES...HELPED BY A MESOSCALE INCREASE ALONG THE PERIPHERY OF THE LAKE AND A SYNOPTIC NORTHEAST PUSH. WINDS SHOULD DIMINISH IN SPEED TONIGHT AND THEN INCREASE AGAIN TUESDAY LATE MORNING INTO THE AFTERNOON. ANY PRECIPITATION CHANCES LOOK TO REMAIN SOUTH OF THE TAF SITES. LOW CLOUDS AND SOME FOG ARE A POSSIBILITY AGAIN TONIGHT...MAINLY AWAY FROM THE METRO AREA. TEMPERATURE/DEW POINT SPREADS ARE LOW FOR MIDDAY DUE TO THE HIGH MOISTURE AND COOLER TEMPERATURES...SETTING THE STAGE FOR THIS AFTER DARK. CONFIDENCE IS LOW ON THIS AT THIS TIME. //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM THAT WIND SPEEDS WILL INCREASE TO 10 KT BY 21Z. * HIGH THAT CIGS WILL REMAIN ABOVE 1500 FT. * LOW IN MVFR FOG DEVELOPING TONIGHT. * MEDIUM IN WIND SPEEDS AND TIMING OF 10 KT ON WEDNESDAY. //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...VFR. THURSDAY...SLIGHT CHANCE OF TSRA. FRIDAY...VFR. SATURDAY...VFR. SUNDAY...SLIGHT CHANCE OF TSRA. MONDAY...CHANCE OF TSRA. MTF/RODRIGUEZ && .MARINE... 206 PM CDT WEAK FLOW IS OVER THE REGION AND THE COLD FRONT IS SOUTH OF THE LAKE. NORTH TO NORTHEAST WINDS 10-20 KT ARE EXPECTED THROUGH THIS AFTERNOON AND THEN WINDS WILL SLOWLY DIMINISH TO AROUND 10 KT BY WEDNESDAY MORNING. WINDS INCREASE TO 10-20 KT TOMORROW AFTERNOON. THE HIGH SHIFTS EAST OF THE LAKE THURSDAY WITH WINDS BECOMING EAST. WINDS REMAIN EAST AT OR BELOW 15 KT THROUGH THE END OF THE WEEK. GUIDANCE DIFFERS ON WHEN THE NEXT LOW WILL IMPACT THE AREA EARLY NEXT WEEK...BUT IN GENERAL WEAK FLOW CONTINUES WITH NO MAJOR IMPACTS EXPECTED. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1257 PM CDT Tue Aug 5 2014 .UPDATE... ISSUED AT 1030 AM CDT TUE AUG 5 2014 Will update the forecast today to adjust sky cover with more low clouds from Peoria north today and cooler highs in the lower 80s. Will continue 20-30% chances of showers and thunderstorms over eastern IL this afternoon. Seasonably warm highs in the mid 80s over much of CWA with upper 80s near Lawrenceville and Robinson by Wabash river valley. Rather humid today with dewpoints in the mid 60s to near 70F with lowest dewpoints in southeast IL. Short wave that brought locally heavy rains of 1.5-3.5 inches around the Peoria metro area last night has shifted east and south of central IL late this morning. Showers and isolated thunderstorms have exited southeast IL during mid morning so by late morning ILX CWA is dry. Low clouds of 500-1200 feet from Peoria north while patches of clouds above 3k ft over eastern IL from I-57 east. 10 am temps range from near 70F far ne CWA by Lacon and Danville where clouds prevail, to upper 70s from Springfield sw where more sunshine this morning. Dewpoints range from mid 60s over eastern IL to near 70F from Macomb to Springfield west. A frontal boundary just se of the IL river will continue to press slowly se into southeast IL later today. Even though we are on back side of short wave exiting se of IL today, the boundary could develop isolated convection this afternoon as it pushes through areas se of I-55. SPC has 5% risk of severe storms this afternoon and into tonight over Nebraska and western IA and then has 5% risk of severe hail/wind over central IL Wed afternoon/evening and slight chance of severe storms (15% of large hail and damaging wind gusts) sw of a Canton to Lincoln line. HUETTL && .SHORT TERM...Today through Thursday Scattered showers associated with a short-wave trough will continue to work their way east/southeast across the KILX CWA early this morning. Most of the precip will be east of the I-55 corridor by 12z, then into Indiana by 18z as trough passes to the east. Subsidence on the back side of the wave should lead to a mostly dry afternoon, although HRRR is hinting that a few additional showers may fire across the E/NE during the afternoon. Will go with isolated to scattered wording for today, as areal coverage will be rather limited. Morning clouds will gradually clear, with partly sunny conditions expected later in the day. Will be another warm/humid day with highs once again reaching the middle 80s. A lull in the precip chances will occur this afternoon through the evening as short-wave ridging prevails. The next in a series of waves will begin to approach from the northwest overnight, with all model solutions showing a large area of showers/thunder developing along/north of a stalled frontal boundary draped across Iowa. Precip will begin to push into the Illinois River Valley toward dawn Wednesday, so will carry low chance PoPs after midnight along/northwest of the Illinois River with dry conditions elsewhere. Showers and thunderstorms will spread across much of central Illinois on Wednesday, primarily impacting locations west of the I-57 corridor. Will carry likely PoPs across the west, tapering down to low chance along the Indiana border accordingly. SPC has indicated that a slight risk for severe storms may develop Wednesday afternoon and evening across northern Missouri into southwest Illinois. This severe risk is contingent upon vigorous short-wave currently over Utah maintaining its strength as it approaches from the west Wednesday evening. NAM remains most aggressive with this feature, while GFS is quite a bit weaker. If stronger NAM verifies, enough lift will be generated along/south of surface boundary within the unstable and moderately sheared airmass to support a few strong to severe storms with large hail/gusty winds across the southwest CWA Wednesday evening. Otherwise, expect showers and thunderstorms to become more numerous across the entire area Wednesday night into Thursday as upper wave tracks across the area and interacts with the stalled frontal boundary and very moist airmass. .LONG TERM...Friday through Monday Once the Thursday wave passes to the east, frontal boundary will begin to get pushed southward by the end of the week. Models continue to struggle with this evolution, but general consensus shifts best precip chances into the Ohio River Valley on Friday, then even further south over the weekend. As a result, will focus chance PoPs across only the southern CWA on Friday. After that, Saturday and Sunday appear to be largely dry before the next potential wave approaches within the prevailing northwesterly flow pattern early next week. Will therefore go with a dry forecast during the weekend, with low chance PoPs returning by Monday. BARNES && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z Wednesday AFTERNOON) ISSUED AT 1255 PM CDT TUE AUG 5 2014 MVFR ceilings to occur over central IL airports next few hours and gradaully lift to VFR ceilings or even scattered out especially at SPI and DEC. A frontal boundary near I-72 will slowly move into southeast IL later this afternoon. Isolated showers and thunderstorms to occur over east central and se IL this afternoon with CMI and DEC having best chances of seeing this, but feel chances are too low to even mention VCTS. Another short wave diving se into IL late tonight and Wed to likely return chances of showers and thunderstorms starting at PIA at 10Z along I-55 from 11z-12Z and DEC and CMI from 13-14Z. Have MVFR ceilings and vsbys arriving by Wed morning with the rain and some fog also possible. West winds near 5 kts along I-72 to turn NE early this afternoon as front slips south of I-72. Expect NE winds to remain light tonight and near 5 kts Wed morning. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HUETTL LONG TERM...BARNES AVIATION...HUETTL
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1051 AM CDT TUE AUG 5 2014 .DISCUSSION... 1013 AM CDT NO BIG CHANGES TO GOING FORECAST FOR TODAY. VISIBLE SATELLITE IMAGERY SHOWS FAIRLY EXTENSIVE STRATUS ACROSS THE CWA THIS MORNING. THE HIGH SUN ANGLE AND LACK OF LOW LEVEL INVERSION TO TRAP THIS MOISTURE WOULD SUGGEST THAT IT SHOULD MIX OUT THIS AFTERNOON WITH AT LEAST PARTIAL CLEARING. GIVEN THE ANTICIPATED SUNSHINE MADE NO CHANGES TO GOING HIGH TEMP FORECAST FOR TODAY...BUT DID SLOW THE TEMP RISE IN THE HOURLY GRIDS INTO EARLY AFTERNOON DUE TO THE CLOUDINESS. ILL DEFINED COLD FRONT WILL CONTINUE SAG SLOWLY SOUTH ACROSS THE AREA THIS AFTERNOON...BUT LOW LEVEL CONVERGENCE ALONG THE FRONT WILL BE QUITE WEAK AND WATER VAPOR IMAGERY AND MODEL GUIDANCE DO NOT SHOW ANY UPSTREAM SHORTWAVES TO ENHANCE LARGE SCALE ASCENT. DESPITE THESE NEGATIVES...MODIFYING THE ILX 12Z SOUNDING FOR EXPECTED AFTERNOON CONDITIONS YIELDS SEVERAL HUNDRED JOULES OF MLCAPE WITH LITTLE INHIBITION...SO STILL POSSIBLE THAT ISOLATED SHRA/TSRA COULD DEVELOP OVER SOUTHEAST CWA THIS AFTERNOON. IZZI //PREV DISCUSSION... 355 AM CDT FORECAST CONCERNS FOCUS ON RAIN AND THUNDER CHANCES DIMINISHING FROM THE NORTH TODAY AS WEAK COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE FORECAST AREA...AND AGAIN WEDNESDAY INTO THURSDAY AS ANOTHER SHORT WAVE AND JET STREAK DIG SOUTHEAST ACROSS THE REGION. AREA OF RAIN/THUNDERSTORMS HAS PUSHED SOUTHEAST ACROSS THE FORECAST AREA SINCE YESTERDAY AFTERNOON IN ASSOCIATION WITH A WEAK COLD FRONT AND A DIGGING MID-LEVEL SHORT WAVE TROUGH. MOST OF THE RAIN WAS SOUTHEAST OF A PRINCETON ILLINOIS TO GARY INDIANA LINE AS OF 3 AM AND SHOULD CONTINUE TO FOCUS OVER THE SOUTHEAST THIRD OR SO OF THE CWA THIS MORNING AS THE MID-LEVEL WAVE AND AN EMBEDDED MCV PROPAGATE INTO INDIANA. HARD TO PLACE THE ACTUAL COLD FRONTAL BOUNDARY GIVEN LIGHT GRADIENT AND CONVECTIVE OUTFLOW CONTAMINATED SURFACE WIND FIELD...THOUGH IT APPEARS TO BE SOMEWHERE FROM NORTH OF KORD TO KDKB TO SOUTH OF KSQI IN LATEST SURFACE ANALYSIS. FRONT IS PROGGED TO CONTINUE TO DRIFT SOUTHEAST THIS MORNING BEHIND WEAK SURFACE WAVE WITH BEST POTENTIAL FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT LATER THIS MORNING AND THIS AFTERNOON TO BE ALONG/SOUTH OF THE FRONT ACROSS THE SOUTH/SOUTHEAST PART OF THE CWA. ALSO...WITH LITTLE PUSH TO THE FRONT AT THIS TIME...LOW STRATUS AND FOG WAS DEVELOPING INTO NORTHWEST AND NORTH CENTRAL IL...AND WILL LIKELY LINGER AFTER SUNRISE THIS MORNING. SOMEWHAT DRIER LOW LEVEL AIR WILL FILTER IN FROM THE NORTH BY TONIGHT AS HIGH PRESSURE SPREADS ACROSS THE NORTHERN GREAT LAKES REGION...AND THE FRONT MOVES INTO DOWNSTATE IL/IN. GUIDANCE IS IN GOOD AGREEMENT IN DIGGING ANOTHER SHORT WAVE ACROSS THE MIDWEST WEDNESDAY INTO THURSDAY HOWEVER...WITH OVERRUNNING OF THE LOW LEVEL FRONTAL ZONE DEVELOPING FROM NORTHWEST IOWA INTO CENTRAL ILLINOIS. MODEL TREND HAS BEEN TO DEVELOP FAIRLY STRONG FRONTOGENESIS ALONG THE ELEVATED BAROCLINIC ZONE BENEATH THE RIGHT ENTRANCE REGION OF A 90 KT UPPER JET STREAK THROUGH THURSDAY...BRINGING A COUPLE OF PERIODS OF RAIN AND THUNDERSTORMS BACK INTO THE FORECAST AREA FROM WEDNESDAY MORNING THROUGH THURSDAY NIGHT. THE POTENTIAL EXISTS FOR SOME LOCALLY HEAVY RAINFALL THURSDAY/THURSDAY NIGHT ACROSS SOUTHERN PARTS OF THE CWA...AS 2+ INCH PWATS SPREAD NORTH. GFS/WRF BOTH DELIVER MORE THAN AN INCH OF RAIN TO THE SOUTHERN CWA DURING THIS TIME. FRONTAL ZONE THEN SHIFTS SOUTH INTO THE OHIO VALLEY AS HIGH PRESSURE STRENGTHENS ACROSS THE NORTHERN GREAT LAKES REGION FRIDAY AND SATURDAY. EASTERLY LOW LEVEL FLOW AROUND THE HIGH FAVORS DRY WEATHER AND PREFER THE DRIER ECMWF SOLUTION FOR THIS PERIOD. ANOTHER UPPER TROUGH APPROACHES THE REGION BY MONDAY HOWEVER...WITH AN INCREASE IN RAIN CHANCES LATER SUNDAY INTO MONDAY. TEMPERATURES THROUGH THE FORECAST PERIOD WILL AVERAGE JUST A BIT BELOW NORMAL WITH THE COOLEST DAYS WEDNESDAY-THURSDAY REMAINING IN THE 70S. OTHERWISE AROUND 80/LOWER 80S APPEAR REASONABLE. SURFACE FLOW WILL BE OFF THE LAKE THROUGH MOST OF THE PERIOD KEEPING AREAS NEAR LAKE MICHIGAN A LITTLE COOLER. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * WINDS INCREASING TO AROUND 10KT DURING THE MID-AFTERNOON. * MVFR CEILINGS LINGERING POSSIBLY THROUGH EARLY AFTERNOON. * FOG POSSIBLE ONCE AGAIN TONIGHT. RODRIGUEZ/MTF //DISCUSSION...UPDATED 12Z... RADAR IMAGERY DEPICTING LAST AREA OF SHOWERS EXITING TO THE EAST OF THE TERMINALS THIS MORNING...WHILE WEAK SURFACE TROUGH AND FRONT REMAIN SITUATED ACROSS THE AREA. WITHIN THIS WEAK SURFACE PATTERN...FOG AND LOW STRATUS HAVE DEVELOPED EARLY THIS MORNING. SOLID IFR CEILINGS ARE CURRENTLY SITUATED MORE TOWARDS FAR NORTHERN ILLINOIS AT THIS HOUR...WITH MVFR CEILINGS LOCATED OVER NORTHEAST ILLINOIS. WHILE RFD OBSERVES IFR OVER THE NEXT SEVERAL HOURS...EXPECT THE REMAINING SITES TO ONLY OBSERVE MVFR CEILINGS. A SLOW UPWARD TREND IN THESE CEILINGS WILL LIKELY OCCUR BEFORE THEY SCATTER BY MID/LATE MORNING. SURFACE TROUGH/FRONT WILL PUSH THROUGH LATER THIS MORNING WITH THE CURRENT LIGHT/VARIABLE WINDS BECOMING MORE NORTHEAST. DO THINK THERE WILL BE AN INCREASE IN SPEEDS BY EARLY AFTERNOON...AS AN EXTRA LAKE PUSH OCCURS. OVERALL PRECIP CHANCES APPEAR TO BE LOW BUT COULD SEE SOME ISOLATED SHOWER DEVELOPMENT WITH THIS ADDED LAKE PUSH THIS AFTERNOON. WITH LOW CONFIDENCE...HAVE OPTED TO LEAVE OUT ANY MENTION OF PRECIP AT THIS TIME. OUTSIDE OF SOME PATCHY FOG ONCE AGAIN TONIGHT...EXPECT VFR CONDITIONS TO BE IN PLACE FOR THE REMAINDER OF THE FORECAST PERIOD AS NEXT CHANCE FOR PRECIP FOR THE AREA ON WEDNESDAY WILL REMAIN JUST SOUTH OF ALL THE TERMINALS. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM IN SPEED OF NORTHEAST WINDS REACHING 10 KT AT 20Z. * MEDIUM WITH CEILING THROUGH EARLY AFTERNOON. * LOW IN FOG REDEVELOPMENT TONIGHT. RODRIGUEZ/MTF //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...VFR. THURSDAY...SLIGHT CHANCE OF TSRA. FRIDAY...VFR. SATURDAY...VFR. SUNDAY...SLIGHT CHANCE OF TSRA. MONDAY...CHANCE OF TSRA. RODRIGUEZ && .MARINE... 434 AM CDT AS A WEAK SURFACE TROUGH OF LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY STRETCHED FROM THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY TO THE SOUTHERN PORTIONS OF THE LAKE CONTINUE TO SLOWLY MOVE TO THE SOUTHEAST TODAY...THE VARIABLE WINDS CURRENTLY BEING OBSERVED OVER THE SOUTHERN END OF THE LAKE WILL BECOME MORE NORTHERLY THIS MORNING LIKE THE REMAINDER OF THE LAKE. DO EXPECT THESE NORTHERLY WINDS TO INCREASE TO THE 10 TO 20 KT RANGE TODAY...WHILE WAVES ALSO BUILD TO 2 TO 4 FEET. THIS INCREASE IN SPEEDS WILL BE BRIEF THOUGH AS WINDS DIMINISH TONIGHT AND THEN REMAIN ON THE LIGHTER SIDE THROUGH THE REST OF THE FORECAST PERIOD...AS HIGH PRESSURE TO THE NORTHWEST SETTLES IN THROUGH THE REST OF THE WORK WEEK. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1043 AM CDT Tue Aug 5 2014 .UPDATE... ISSUED AT 1030 AM CDT TUE AUG 5 2014 Will update the forecast today to adjust sky cover with more low clouds from Peoria north into midday. Will continue 20-30% chances of showers and thunderstorms over eastern IL this afternoon. Seasonably warm highs in the mid 80s over much of CWA with upper 80s near Lawrenceville and Robinson by Wabash river valley. Rather humid today with dewpoints in the mid 60s to near 70F with lowest dewpoints in southeast IL. Short wave that brought locally heavy rains of 1.5-3.5 inches around the Peoria metro area last night has shifted east and south of central IL late this morning. Showers and isolated thunderstorms have exited southeast IL during mid morning so by late morning ILX CWA is dry. Low clouds of 500-1200 feet from Peoria north while patches of clouds above 3k ft over eastern IL from I-57 east. 10 am temps range from near 70F far ne CWA by Lacon and Danville where clouds prevail, to upper 70s from Springfield sw where more sunshine this morning. Dewpoints range from mid 60s over eastern IL to near 70F from Macomb to Springfield west. A frontal boundary just se of the IL river will continue to press slowly se into southeast IL later today. Even though we are on back side of short wave exiting se of IL today, the boundary could develop isolated convection this afternoon as it pushes through areas se of I-55. SPC has 5% risk of severe storms this afternoon and into tonight over Nebraska and western IA and then has 5% risk of severe hail/wind over central IL Wed afternoon/evening and slight chance of severe storms (15% of large hail and damaging wind gusts) sw of a Canton to Lincoln line. HUETTL && .SHORT TERM...Today through Thursday Scattered showers associated with a short-wave trough will continue to work their way east/southeast across the KILX CWA early this morning. Most of the precip will be east of the I-55 corridor by 12z, then into Indiana by 18z as trough passes to the east. Subsidence on the back side of the wave should lead to a mostly dry afternoon, although HRRR is hinting that a few additional showers may fire across the E/NE during the afternoon. Will go with isolated to scattered wording for today, as areal coverage will be rather limited. Morning clouds will gradually clear, with partly sunny conditions expected later in the day. Will be another warm/humid day with highs once again reaching the middle 80s. A lull in the precip chances will occur this afternoon through the evening as short-wave ridging prevails. The next in a series of waves will begin to approach from the northwest overnight, with all model solutions showing a large area of showers/thunder developing along/north of a stalled frontal boundary draped across Iowa. Precip will begin to push into the Illinois River Valley toward dawn Wednesday, so will carry low chance PoPs after midnight along/northwest of the Illinois River with dry conditions elsewhere. Showers and thunderstorms will spread across much of central Illinois on Wednesday, primarily impacting locations west of the I-57 corridor. Will carry likely PoPs across the west, tapering down to low chance along the Indiana border accordingly. SPC has indicated that a slight risk for severe storms may develop Wednesday afternoon and evening across northern Missouri into southwest Illinois. This severe risk is contingent upon vigorous short-wave currently over Utah maintaining its strength as it approaches from the west Wednesday evening. NAM remains most aggressive with this feature, while GFS is quite a bit weaker. If stronger NAM verifies, enough lift will be generated along/south of surface boundary within the unstable and moderately sheared airmass to support a few strong to severe storms with large hail/gusty winds across the southwest CWA Wednesday evening. Otherwise, expect showers and thunderstorms to become more numerous across the entire area Wednesday night into Thursday as upper wave tracks across the area and interacts with the stalled frontal boundary and very moist airmass. .LONG TERM...Friday through Monday Once the Thursday wave passes to the east, frontal boundary will begin to get pushed southward by the end of the week. Models continue to struggle with this evolution, but general consensus shifts best precip chances into the Ohio River Valley on Friday, then even further south over the weekend. As a result, will focus chance PoPs across only the southern CWA on Friday. After that, Saturday and Sunday appear to be largely dry before the next potential wave approaches within the prevailing northwesterly flow pattern early next week. Will therefore go with a dry forecast during the weekend, with low chance PoPs returning by Monday. BARNES && .AVIATION... ISSUED 630 AM CDT Tue Aug 5 2014 Challenging forecast thru late morning as copious low level moisture left over from last night`s rainfall and light wind flow will create variable conditions with respect to vsbys and cigs thru the morning. Watching a band of stratus drifting south out of northern Illinois which may affect the PIA and BMI terminals this morning. After that, forecast soundings indicate we may see some MVFR cigs for a time into early this afternoon, especially from KPIA to KBMI and possibly into KCMI. Based on the sounding data, cigs in the 2500-3500 foot range will be possible before we trend towards scattered bases around 4000 feet aftr 19z. Confidence on this scenario rather low as lower cloud deck appears to be breaking up some as it tracks south early this morning. Winds once again a non-factor although we will see a frontal boundary slip south of the area switching the wind direction more into a north to northeast direction later this morning into the afternoon hours. Some mid to high level clouds will be the story for tonight with some fog/hz developing again later in the evening. SMITH && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HUETTL LONG TERM...BARNES AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
849 AM CDT TUE AUG 5 2014 .DISCUSSION... 355 AM CDT FORECAST CONCERNS FOCUS ON RAIN AND THUNDER CHANCES DIMINISHING FROM THE NORTH TODAY AS WEAK COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE FORECAST AREA...AND AGAIN WEDNESDAY INTO THURSDAY AS ANOTHER SHORT WAVE AND JET STREAK DIG SOUTHEAST ACROSS THE REGION. AREA OF RAIN/THUNDERSTORMS HAS PUSHED SOUTHEAST ACROSS THE FORECAST AREA SINCE YESTERDAY AFTERNOON IN ASSOCIATION WITH A WEAK COLD FRONT AND A DIGGING MID-LEVEL SHORT WAVE TROUGH. MOST OF THE RAIN WAS SOUTHEAST OF A PRINCETON ILLINOIS TO GARY INDIANA LINE AS OF 3 AM AND SHOULD CONTINUE TO FOCUS OVER THE SOUTHEAST THIRD OR SO OF THE CWA THIS MORNING AS THE MID-LEVEL WAVE AND AN EMBEDDED MCV PROPAGATE INTO INDIANA. HARD TO PLACE THE ACTUAL COLD FRONTAL BOUNDARY GIVEN LIGHT GRADIENT AND CONVECTIVE OUTFLOW CONTAMINATED SURFACE WIND FIELD...THOUGH IT APPEARS TO BE SOMEWHERE FROM NORTH OF KORD TO KDKB TO SOUTH OF KSQI IN LATEST SURFACE ANALYSIS. FRONT IS PROGGED TO CONTINUE TO DRIFT SOUTHEAST THIS MORNING BEHIND WEAK SURFACE WAVE WITH BEST POTENTIAL FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT LATER THIS MORNING AND THIS AFTERNOON TO BE ALONG/SOUTH OF THE FRONT ACROSS THE SOUTH/SOUTHEAST PART OF THE CWA. ALSO...WITH LITTLE PUSH TO THE FRONT AT THIS TIME...LOW STRATUS AND FOG WAS DEVELOPING INTO NORTHWEST AND NORTH CENTRAL IL...AND WILL LIKELY LINGER AFTER SUNRISE THIS MORNING. SOMEWHAT DRIER LOW LEVEL AIR WILL FILTER IN FROM THE NORTH BY TONIGHT AS HIGH PRESSURE SPREADS ACROSS THE NORTHERN GREAT LAKES REGION...AND THE FRONT MOVES INTO DOWNSTATE IL/IN. GUIDANCE IS IN GOOD AGREEMENT IN DIGGING ANOTHER SHORT WAVE ACROSS THE MIDWEST WEDNESDAY INTO THURSDAY HOWEVER...WITH OVERRUNNING OF THE LOW LEVEL FRONTAL ZONE DEVELOPING FROM NORTHWEST IOWA INTO CENTRAL ILLINOIS. MODEL TREND HAS BEEN TO DEVELOP FAIRLY STRONG FRONTOGENESIS ALONG THE ELEVATED BAROCLINIC ZONE BENEATH THE RIGHT ENTRANCE REGION OF A 90 KT UPPER JET STREAK THROUGH THURSDAY...BRINGING A COUPLE OF PERIODS OF RAIN AND THUNDERSTORMS BACK INTO THE FORECAST AREA FROM WEDNESDAY MORNING THROUGH THURSDAY NIGHT. THE POTENTIAL EXISTS FOR SOME LOCALLY HEAVY RAINFALL THURSDAY/THURSDAY NIGHT ACROSS SOUTHERN PARTS OF THE CWA...AS 2+ INCH PWATS SPREAD NORTH. GFS/WRF BOTH DELIVER MORE THAN AN INCH OF RAIN TO THE SOUTHERN CWA DURING THIS TIME. FRONTAL ZONE THEN SHIFTS SOUTH INTO THE OHIO VALLEY AS HIGH PRESSURE STRENGTHENS ACROSS THE NORTHERN GREAT LAKES REGION FRIDAY AND SATURDAY. EASTERLY LOW LEVEL FLOW AROUND THE HIGH FAVORS DRY WEATHER AND PREFER THE DRIER ECMWF SOLUTION FOR THIS PERIOD. ANOTHER UPPER TROUGH APPROACHES THE REGION BY MONDAY HOWEVER...WITH AN INCREASE IN RAIN CHANCES LATER SUNDAY INTO MONDAY. TEMPERATURES THROUGH THE FORECAST PERIOD WILL AVERAGE JUST A BIT BELOW NORMAL WITH THE COOLEST DAYS WEDNESDAY-THURSDAY REMAINING IN THE 70S. OTHERWISE AROUND 80/LOWER 80S APPEAR REASONABLE. SURFACE FLOW WILL BE OFF THE LAKE THROUGH MOST OF THE PERIOD KEEPING AREAS NEAR LAKE MICHIGAN A LITTLE COOLER. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * WINDS BECOMING LIGHT NORTHEAST BY 15Z...LIKELY INCREASING TO 10KT OR HIGHER DURING THE EARLY AFTERNOON. * MVFR CEILINGS THIS MORNING. * LOW CHANCE FOR A BRIEF SHOWER THIS AFTERNOON. * FOG POSSIBLE ONCE AGAIN TONIGHT. RODRIGUEZ/MTF //DISCUSSION...UPDATED 12Z... RADAR IMAGERY DEPICTING LAST AREA OF SHOWERS EXITING TO THE EAST OF THE TERMINALS THIS MORNING...WHILE WEAK SURFACE TROUGH AND FRONT REMAIN SITUATED ACROSS THE AREA. WITHIN THIS WEAK SURFACE PATTERN...FOG AND LOW STRATUS HAVE DEVELOPED EARLY THIS MORNING. SOLID IFR CEILINGS ARE CURRENTLY SITUATED MORE TOWARDS FAR NORTHERN ILLINOIS AT THIS HOUR...WITH MVFR CEILINGS LOCATED OVER NORTHEAST ILLINOIS. WHILE RFD OBSERVES IFR OVER THE NEXT SEVERAL HOURS...EXPECT THE REMAINING SITES TO ONLY OBSERVE MVFR CEILINGS. A SLOW UPWARD TREND IN THESE CEILINGS WILL LIKELY OCCUR BEFORE THEY SCATTER BY MID/LATE MORNING. SURFACE TROUGH/FRONT WILL PUSH THROUGH LATER THIS MORNING WITH THE CURRENT LIGHT/VARIABLE WINDS BECOMING MORE NORTHEAST. DO THINK THERE WILL BE AN INCREASE IN SPEEDS BY EARLY AFTERNOON...AS AN EXTRA LAKE PUSH OCCURS. OVERALL PRECIP CHANCES APPEAR TO BE LOW BUT COULD SEE SOME ISOLATED SHOWER DEVELOPMENT WITH THIS ADDED LAKE PUSH THIS AFTERNOON. WITH LOW CONFIDENCE...HAVE OPTED TO LEAVE OUT ANY MENTION OF PRECIP AT THIS TIME. OUTSIDE OF SOME PATCHY FOG ONCE AGAIN TONIGHT...EXPECT VFR CONDITIONS TO BE IN PLACE FOR THE REMAINDER OF THE FORECAST PERIOD AS NEXT CHANCE FOR PRECIP FOR THE AREA ON WEDNESDAY WILL REMAIN JUST SOUTH OF ALL THE TERMINALS. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 14Z... * MEDIUM IN SPEED OF NORTHEAST WINDS REACHING 10 KT AT 19Z. * MEDIUM WITH CEILING TRENDS THIS MORNING. * LOW IN ANY SHOWERS THIS AFTERNOON. * LOW IN FOG REDEVELOPMENT TONIGHT. RODRIGUEZ/MTF //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...VFR. THURSDAY...SLIGHT CHANCE OF TSRA. FRIDAY...VFR. SATURDAY...VFR. SUNDAY...SLIGHT CHANCE OF TSRA. MONDAY...CHANCE OF TSRA. RODRIGUEZ && .MARINE... 434 AM CDT AS A WEAK SURFACE TROUGH OF LOW PRESSURE AND ASSOCIATED FRONTAL BOUNDARY STRETCHED FROM THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY TO THE SOUTHERN PORTIONS OF THE LAKE CONTINUE TO SLOWLY MOVE TO THE SOUTHEAST TODAY...THE VARIABLE WINDS CURRENTLY BEING OBSERVED OVER THE SOUTHERN END OF THE LAKE WILL BECOME MORE NORTHERLY THIS MORNING LIKE THE REMAINDER OF THE LAKE. DO EXPECT THESE NORTHERLY WINDS TO INCREASE TO THE 10 TO 20 KT RANGE TODAY...WHILE WAVES ALSO BUILD TO 2 TO 4 FEET. THIS INCREASE IN SPEEDS WILL BE BRIEF THOUGH AS WINDS DIMINISH TONIGHT AND THEN REMAIN ON THE LIGHTER SIDE THROUGH THE REST OF THE FORECAST PERIOD...AS HIGH PRESSURE TO THE NORTHWEST SETTLES IN THROUGH THE REST OF THE WORK WEEK. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 641 AM CDT Tue Aug 5 2014 .DISCUSSION... ISSUED 309 AM CDT Tue Aug 5 2014 SHORT TERM...Today through Thursday Scattered showers associated with a short-wave trough will continue to work their way east/southeast across the KILX CWA early this morning. Most of the precip will be east of the I-55 corridor by 12z, then into Indiana by 18z as trough passes to the east. Subsidence on the back side of the wave should lead to a mostly dry afternoon, although HRRR is hinting that a few additional showers may fire across the E/NE during the afternoon. Will go with isolated to scattered wording for today, as areal coverage will be rather limited. Morning clouds will gradually clear, with partly sunny conditions expected later in the day. Will be another warm/humid day with highs once again reaching the middle 80s. A lull in the precip chances will occur this afternoon through the evening as short-wave ridging prevails. The next in a series of waves will begin to approach from the northwest overnight, with all model solutions showing a large area of showers/thunder developing along/north of a stalled frontal boundary draped across Iowa. Precip will begin to push into the Illinois River Valley toward dawn Wednesday, so will carry low chance PoPs after midnight along/northwest of the Illinois River with dry conditions elsewhere. Showers and thunderstorms will spread across much of central Illinois on Wednesday, primarily impacting locations west of the I-57 corridor. Will carry likely PoPs across the west, tapering down to low chance along the Indiana border accordingly. SPC has indicated that a slight risk for severe storms may develop Wednesday afternoon and evening across northern Missouri into southwest Illinois. This severe risk is contingent upon vigorous short-wave currently over Utah maintaining its strength as it approaches from the west Wednesday evening. NAM remains most aggressive with this feature, while GFS is quite a bit weaker. If stronger NAM verifies, enough lift will be generated along/south of surface boundary within the unstable and moderately sheared airmass to support a few strong to severe storms with large hail/gusty winds across the southwest CWA Wednesday evening. Otherwise, expect showers and thunderstorms to become more numerous across the entire area Wednesday night into Thursday as upper wave tracks across the area and interacts with the stalled frontal boundary and very moist airmass. LONG TERM...Friday through Monday Once the Thursday wave passes to the east, frontal boundary will begin to get pushed southward by the end of the week. Models continue to struggle with this evolution, but general consensus shifts best precip chances into the Ohio River Valley on Friday, then even further south over the weekend. As a result, will focus chance PoPs across only the southern CWA on Friday. After that, Saturday and Sunday appear to be largely dry before the next potential wave approaches within the prevailing northwesterly flow pattern early next week. Will therefore go with a dry forecast during the weekend, with low chance PoPs returning by Monday. && .AVIATION... ISSUED 630 AM CDT Tue Aug 5 2014 Challenging forecast thru late morning as copious low level moisture left over from last night`s rainfall and light wind flow will create variable conditions with respect to vsbys and cigs thru the morning. Watching a band of stratus drifting south out of northern Illinois which may affect the PIA and BMI terminals this morning. After that, forecast soundings indicate we may see some MVFR cigs for a time into early this afternoon, especially from KPIA to KBMI and possibly into KCMI. Based on the sounding data, cigs in the 2500-3500 foot range will be possible before we trend towards scattered bases around 4000 feet aftr 19z. Confidence on this scenario rather low as lower cloud deck appears to be breaking up some as it tracks south early this morning. Winds once again a non-factor although we will see a frontal boundary slip south of the area switching the wind direction more into a north to northeast direction later this morning into the afternoon hours. Some mid to high level clouds will be the story for tonight with some fog/hz developing again later in the evening. Smith && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
355 AM CDT TUE AUG 5 2014 .DISCUSSION... 355 AM CDT FORECAST CONCERNS FOCUS ON RAIN AND THUNDER CHANCES DIMINISHING FROM THE NORTH TODAY AS WEAK COLD FRONT CONTINUES TO SAG SOUTH ACROSS THE FORECAST AREA...AND AGAIN WEDNESDAY INTO THURSDAY AS ANOTHER SHORT WAVE AND JET STREAK DIG SOUTHEAST ACROSS THE REGION. AREA OF RAIN/THUNDERSTORMS HAS PUSHED SOUTHEAST ACROSS THE FORECAST AREA SINCE YESTERDAY AFTERNOON IN ASSOCIATION WITH A WEAK COLD FRONT AND A DIGGING MID-LEVEL SHORT WAVE TROUGH. MOST OF THE RAIN WAS SOUTHEAST OF A PRINCETON ILLINOIS TO GARY INDIANA LINE AS OF 3 AM AND SHOULD CONTINUE TO FOCUS OVER THE SOUTHEAST THIRD OR SO OF THE CWA THIS MORNING AS THE MID-LEVEL WAVE AND AN EMBEDDED MCV PROPAGATE INTO INDIANA. HARD TO PLACE THE ACTUAL COLD FRONTAL BOUNDARY GIVEN LIGHT GRADIENT AND CONVECTIVE OUTFLOW CONTAMINATED SURFACE WIND FIELD...THOUGH IT APPEARS TO BE SOMEWHERE FROM NORTH OF KORD TO KDKB TO SOUTH OF KSQI IN LATEST SURFACE ANALYSIS. FRONT IS PROGGED TO CONTINUE TO DRIFT SOUTHEAST THIS MORNING BEHIND WEAK SURFACE WAVE WITH BEST POTENTIAL FOR DIURNAL SHOWER/THUNDERSTORM DEVELOPMENT LATER THIS MORNING AND THIS AFTERNOON TO BE ALONG/SOUTH OF THE FRONT ACROSS THE SOUTH/SOUTHEAST PART OF THE CWA. ALSO...WITH LITTLE PUSH TO THE FRONT AT THIS TIME...LOW STRATUS AND FOG WAS DEVELOPING INTO NORTHWEST AND NORTH CENTRAL IL...AND WILL LIKELY LINGER AFTER SUNRISE THIS MORNING. SOMEWHAT DRIER LOW LEVEL AIR WILL FILTER IN FROM THE NORTH BY TONIGHT AS HIGH PRESSURE SPREADS ACROSS THE NORTHERN GREAT LAKES REGION...AND THE FRONT MOVES INTO DOWNSTATE IL/IN. GUIDANCE IS IN GOOD AGREEMENT IN DIGGING ANOTHER SHORT WAVE ACROSS THE MIDWEST WEDNESDAY INTO THURSDAY HOWEVER...WITH OVERRUNNING OF THE LOW LEVEL FRONTAL ZONE DEVELOPING FROM NORTHWEST IOWA INTO CENTRAL ILLINOIS. MODEL TREND HAS BEEN TO DEVELOP FAIRLY STRONG FRONTOGENESIS ALONG THE ELEVATED BAROCLINIC ZONE BENEATH THE RIGHT ENTRANCE REGION OF A 90 KT UPPER JET STREAK THROUGH THURSDAY...BRINGING A COUPLE OF PERIODS OF RAIN AND THUNDERSTORMS BACK INTO THE FORECAST AREA FROM WEDNESDAY MORNING THROUGH THURSDAY NIGHT. THE POTENTIAL EXISTS FOR SOME LOCALLY HEAVY RAINFALL THURSDAY/THURSDAY NIGHT ACROSS SOUTHERN PARTS OF THE CWA...AS 2+ INCH PWATS SPREAD NORTH. GFS/WRF BOTH DELIVER MORE THAN AN INCH OF RAIN TO THE SOUTHERN CWA DURING THIS TIME. FRONTAL ZONE THEN SHIFTS SOUTH INTO THE OHIO VALLEY AS HIGH PRESSURE STRENGTHENS ACROSS THE NORTHERN GREAT LAKES REGION FRIDAY AND SATURDAY. EASTERLY LOW LEVEL FLOW AROUND THE HIGH FAVORS DRY WEATHER AND PREFER THE DRIER ECMWF SOLUTION FOR THIS PERIOD. ANOTHER UPPER TROUGH APPROACHES THE REGION BY MONDAY HOWEVER...WITH AN INCREASE IN RAIN CHANCES LATER SUNDAY INTO MONDAY. TEMPERATURES THROUGH THE FORECAST PERIOD WILL AVERAGE JUST A BIT BELOW NORMAL WITH THE COOLEST DAYS WEDNESDAY-THURSDAY REMAINING IN THE 70S. OTHERWISE AROUND 80/LOWER 80S APPEAR REASONABLE. SURFACE FLOW WILL BE OFF THE LAKE THROUGH MOST OF THE PERIOD KEEPING AREAS NEAR LAKE MICHIGAN A LITTLE COOLER. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LINGERING SHOWERS EARLY THIS MORNING...WITH POSSIBLE REDEVELOPMENT BY MID MORNING. * FOG THIS MORNING...WITH OUTSIDE POSSIBILITY FOR BRIEF IFR CEILINGS. * VARYING WIND EARLY THIS MORNING BECOMING NORTHEAST. RODRIGUEZ //DISCUSSION...UPDATED 06Z... COMPLEX FORECAST EARLY THIS MORNING OWING TO REMAINING SHOWERS...A RELAXED SURFACE PATTERN WITH LINGERING BOUNDARIES SITUATED ACROSS THE REGION...AND DEVELOPING FOG THIS MORNING. LATEST RADAR IMAGERY DEPICTING AREA OF PRECIP SLOWLY MOVING EAST THROUGH NORTHEAST ILLINOIS AND NORTHWEST INDIANA...AND EXPECT THIS SLOW TREND TO CONTINUE AND EXIT THE REMAINING TERMINALS OVER THE NEXT ONE TO THREE HOURS. VFR CEILINGS IN PLACE WITH THIS LIKELY TO CONTINUE BUT WITH THE ADDED MOISTURE AND RELAXED SURFACE PATTERN AS WELL AS SLOWLY CLEARING SKIES...LOWER CEILINGS COULD DEVELOP EARLY THIS MORNING. HAVE MORE CONFIDENCE WITH FOG DEVELOPING THAN THESE LOWER CEILINGS AND HAVE LEFT OUT ANY MENTION OF IFR CEILINGS IN THE TAF...BUT WILL NEED TO CONTINUE TO MONITOR TRENDS. LIKELY SCENARIO FOR PRECIP CHANCES FOR LATER THIS MORNING INTO MID DAY WOULD BE FOR ANY FURTHER DEVELOPMENT TO BE JUST SOUTH OF THE TERMINALS WITH GYY HAVING THE BEST CHANCES. WILL NEED TO MONITOR THIS AS WELL WITH SOME ISOLATED SHOWER DEVELOPMENT PERSISTING OVER NORTHWEST ILLINOIS AT THIS TIME...AND WITH SHORT TERM GUIDANCE HINTING AT THIS POSSIBILITY OVER THE REMAINING TERMINALS LATER THIS MORNING. WINDS WILL LIKELY CONTINUE TO VARY AS THIS PRECIP PUSHES THROUGH...BUT AM ANTICIPATING SPEEDS TO REMAIN UNDER 10KT. WINDS WILL THEN TURN TO THE NORTHEAST LATER THIS MORNING AND REMAIN THIS DIRECTION THROUGH THE REST OF THE FORECAST PERIOD. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM HIGH CONFIDENCE WITH SHOWER TRENDS EARLY THIS MORNING...LOW CONFIDENCE WITH POSSIBLE REDEVELOPMENT. * HIGH CONFIDENCE WITH FOG AND MEDIUM CONFIDENCE WITH VIS...LOW CONFIDENCE WITH ANY BRIEF IFR CEILINGS. * MEDIUM CONFIDENCE WITH WIND SPEED/DIRECTION. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY...SLIGHT CHANCE OF EVE TSRA. EAST-NORTHEAST WINDS. THURSDAY...SLIGHT CHANCE OF TSRA. EAST-NORTHEAST WINDS. FRIDAY-SATURDAY...VFR LIKELY. EAST WINDS. BEACHLER && .MARINE... 222 PM CDT WEAK HIGH PRESSURE REMAINS OVER THE REGION WHILE A COLD FRONT HAS STALLED OVER THE SOUTHERN END OF THE LAKE. WINDS ARE NORTH BEHIND THE FRONT AND THEN ONSHORE SOUTH OF THE FRONT. THE FRONT WILL RESUME ITS SOUTHERLY PUSH LATE TONIGHT AND CLEAR THE SOUTHERN END OF THE LAKE EARLY TUESDAY MORNING. WINDS WILL ALSO INCREASE TO 10-20 KT TOMORROW OVER THE SOUTHERN TWO THIRDS OF THE LAKE. WAVES CONTINUE TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. HIGH PRESSURE BUILDS IN BEHIND THE FRONT AND WINDS DIMINISH TUESDAY NIGHT TO 10-15 KT. THE HIGH REMAINS OVER THE LAKE THROUGH THE WEEKEND. NORTH TO NORTHEAST WINDS ARE EXPECTED THROUGH WEDNESDAY NIGHT. THEY THEN BECOME EAST THURSDAY NIGHT AND STAY THERE THROUGH THE WEEKEND AT 15 KT OR LESS. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 309 AM CDT Tue Aug 5 2014 .DISCUSSION... ISSUED 309 AM CDT Tue Aug 5 2014 SHORT TERM...Today through Thursday Scattered showers associated with a short-wave trough will continue to work their way east/southeast across the KILX CWA early this morning. Most of the precip will be east of the I-55 corridor by 12z, then into Indiana by 18z as trough passes to the east. Subsidence on the back side of the wave should lead to a mostly dry afternoon, although HRRR is hinting that a few additional showers may fire across the E/NE during the afternoon. Will go with isolated to scattered wording for today, as areal coverage will be rather limited. Morning clouds will gradually clear, with partly sunny conditions expected later in the day. Will be another warm/humid day with highs once again reaching the middle 80s. A lull in the precip chances will occur this afternoon through the evening as short-wave ridging prevails. The next in a series of waves will begin to approach from the northwest overnight, with all model solutions showing a large area of showers/thunder developing along/north of a stalled frontal boundary draped across Iowa. Precip will begin to push into the Illinois River Valley toward dawn Wednesday, so will carry low chance PoPs after midnight along/northwest of the Illinois River with dry conditions elsewhere. Showers and thunderstorms will spread across much of central Illinois on Wednesday, primarily impacting locations west of the I-57 corridor. Will carry likely PoPs across the west, tapering down to low chance along the Indiana border accordingly. SPC has indicated that a slight risk for severe storms may develop Wednesday afternoon and evening across northern Missouri into southwest Illinois. This severe risk is contingent upon vigorous short-wave currently over Utah maintaining its strength as it approaches from the west Wednesday evening. NAM remains most aggressive with this feature, while GFS is quite a bit weaker. If stronger NAM verifies, enough lift will be generated along/south of surface boundary within the unstable and moderately sheared airmass to support a few strong to severe storms with large hail/gusty winds across the southwest CWA Wednesday evening. Otherwise, expect showers and thunderstorms to become more numerous across the entire area Wednesday night into Thursday as upper wave tracks across the area and interacts with the stalled frontal boundary and very moist airmass. LONG TERM...Friday through Monday Once the Thursday wave passes to the east, frontal boundary will begin to get pushed southward by the end of the week. Models continue to struggle with this evolution, but general consensus shifts best precip chances into the Ohio River Valley on Friday, then even further south over the weekend. As a result, will focus chance PoPs across only the southern CWA on Friday. After that, Saturday and Sunday appear to be largely dry before the next potential wave approaches within the prevailing northwesterly flow pattern early next week. Will therefore go with a dry forecast during the weekend, with low chance PoPs returning by Monday. Barnes && .AVIATION... ISSUED 1137 PM CDT Mon Aug 4 2014 Showers and scattered storms continuing over central Illinois late Monday evening, most concentrated from KPIA southeast. The storms are likely to be out of the KPIA vicinity by the start of the TAF period, and will leave them out of there. KBMI, KCMI and KDEC also likely to see a period of these storms, and have gone with TEMPO groups for a couple hours to reduce visibility to around 2-3SM. Thunder threat around KSPI appears minimal. Have some concerns for visibility overnight, as a frontal boundary settles southward across northern Illinois. Latest satellite imagery showing some fairly substantial cloud breakup across Iowa and more sustained clearing further north in Minnesota. With the amount of rain that has fallen near KPIA Monday evening, any clearing with the light winds will cause visibilities to tank. Latest HRRR and RAP guidance focuses this more in Iowa and northwest Illinois. For now will include a TEMPO group at KPIA to bring visibility down to 3SM, but will need to watch this closely. Further east, the higher clouds should last longer into the night, and have kept visibility restrictions minimal for now. Later parts of the forecast mainly focus on a wind shift to the northwest and then north, as a cold front pushes through the area. Have maintained some VCTS mention at KCMI during the afternoon, with dry conditions elsewhere. Geelhart && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
102 AM CDT TUE AUG 5 2014 .DISCUSSION... 257 PM CDT THE FORECAST CHALLENGES ARE TIMING AND PLACEMENT OF THUNDERSTORM CHANCES THROUGH THIS WEEK WHICH IS PARTICULARLY CHALLENGING TONIGHT...WHILE FOR THE REMAINDER OF THE WORKWEEK THERE IS GRADUALLY INCREASING CONFIDENCE THAT AT LEAST SOME PARTS OF THE AREA WILL REMAIN PRIMARILY IF NOT ENTIRELY DRY. SYNOPSIS AND TONIGHT... A WEAK FRONTAL BOUNDARY DRAPED NEARLY WEST-TO-EAST FROM SOUTH DAKOTA THROUGH FAR SOUTHERN WI AND TO LOWER MI IS VERY SLOWLY SHIFTING SOUTH THIS AFTERNOON. THE PUSH BEHIND THIS WEAK CONVERGENCE ZONE IS ALMOST NON-EXISTENT WITH THE FRONT DRIVEN MORE BY MID/UPPER FORCING AND COOLER STORM OUTFLOWS. OUTSIDE OF SOME CELLS ON THE LAKE BREEZE NEAR CHICAGO....THE BULK OF THE CONVECTION THIS EARLY AFTERNOON HAS BEEN IN WI AND SE MN WHERE UPPER FORCING IS BETTER DUE TO THE APPROACH OF A SHORT WAVE TROUGH. AS THIS TROUGH APPROACHES INTO THE FORECAST AREA DURING THIS EVENING...STORM COVERAGE ACTUALLY WILL LIKELY INCREASE IN OUR FORECAST AREA...THOUGH A VERY GRADUAL WANE ON THE REGIONAL SCOPE IS ANTICIPATED WITH THE LOSS OF HEATING. THE STORMS HAVE BEEN SLOW-MOVING JUST AS THEY HAVE BEEN IN RECENT DAYS WITH LITTLE IN THE WAY OF STEERING FLOW AND WIND SHEAR. RADAR TRENDS FROM WI AND INITIAL EARLY STORMS IN OUR CWA INDICATE VERY PULSEY NATURE TO THE STORMS AND THAT WOULD BE EXPECTED INTO EVENING WITH PRESENT MID 60S DEW POINTS AND 1000-1500 J/KG OF MLCAPE IN A LOW WIND SHEAR ENVIRONMENT. STORMS SHOULD MAINLY TRIGGER OR FESTER ON OUTFLOWS. HAVE SEEN SOME GUSTS OVER 30 KT UPSTREAM...INCLUDING AT LA CROSSE AND MADISON. THOSE TYPE OF GUSTS AND SMALL HAIL ARE POSSIBLE WITH ANY OF THE STRONGER STORMS. HOWEVER THE DISJOINT OF HEATING OF THE DAY AND THE SHORT WAVE...AT LEAST FOR OUR FORECAST AREA...MAY PRECLUDE ANY SUCH STORMS. LOCALLY HEAVY RAIN WILL BE A GIVEN WITH SOME STORMS DUE TO THEIR SLOW MOVING NATURE. IF ANY OF THESE WERE TO PASS OVER A METRO AREA IN PARTICULAR...THERE COULD BE A BRIEF FLOODING CONCERN. OUTFLOWS WILL LEAD TO SOME QUICK TEMPERATURE DROPS THIS EVE. BECAUSE OF THAT SOME TEMPERATURE/DEW POINT SPREADS MAY BE LOW GOING INTO THE OVERNIGHT HOURS WHICH MAY PRESENT POSSIBLE PATCHY GROUND FOG AGAIN. IN ADDITION...WEB CAMS AND REPORTS HAVE INDICATED HAZE IN THE METRO AREA SO HAVE ADDED THAT INTO THE FORECAST THROUGH TUESDAY MORNING. TUESDAY... THE LEFT EXIT REGION OF THE UPPER JET AND ASSOCIATED WAVE WILL LIKELY STILL BE MOVING THROUGH THE FORECAST AREA EARLY IN THE MORNING...AT THIS TIME FAVORED IN THE EASTERN FORECAST AREA. THERE COULD BE SOME SHOWERS AND EVEN SOME STORMS WITH THIS. THE SURFACE BOUNDARY LOOKS TO HAVE MOVED/EVOLVED INTO THE SOUTHERN FORECAST AREA BY TUESDAY AFTERNOON WHERE DEW POINTS WILL AGAIN POOL IN THE MID 60S. INSTABILITY OF 1000 J/KG SHOULD BE ENOUGH TO PROMOTE ISOLATED TO SCATTERED STORMS AGAIN IN THE AFTERNOON AS A SURFACE HIGH BUILDS FROM THE NORTH AGAINST THE BOUNDARY...AIDED PARTLY BY A PUSH OFF THE LAKE. AGAIN STORMS SHOULD BE OF A PULSEY NATURE. SLIGHTLY COOLER HIGH TEMPERATURES ARE EXPECTED ESPECIALLY NORTH AND NEAR THE LAKE. WEDNESDAY THROUGH SUNDAY... THERE HAS BEEN PRONOUNCED MODEL SPREAD FOR NUMEROUS RUNS REGARDING RAIN CHANCES AND MAGNITUDES DURING WEDNESDAY AND THURSDAY. THIS SPREAD HAS NOW LOWERED WITH NCEP MODELS COMING MORE IN LINE WITH THE EC WHICH CONTINUES TO TREND MAINLY SOUTH OF THE AREA. THE BASIC UPPER PATTERN IS NORTHWEST FLOW ALOFT WITH THE OLD SURFACE BOUNDARY SERVING AS A STATIONARY/WARM FRONT...WITH ASCENT ALONG AND NORTH OF IT BEING SUPPORTED BY RIGHT ENTRANCE REGION UPPER DYNAMICS. THE CHALLENGING THING IS THAT DRIER MID TO LOW-LEVEL AIR WILL BE WORKING IN FROM THE NORTHEAST BEHIND THE TUESDAY BOUNDARY AND THAT LIKELY IS TO PROVIDE A TIGHT GRADIENT AT LEAST AT TIMES IN PRECIP ACROSS THE REGION WEDNESDAY THROUGH THURSDAY. THE FURTHEST OUTLYING NORTH MODEL HAD BEEN THE 12KM NAM-WRF...WHICH EVEN ITS 4KM NESTED SOLUTION DOES NOT AGREE WITH. THE 12Z GFS TRENDED FURTHER SOUTH AND EVEN ITS COURSER RESOLUTION IS LIKELY PARTLY RESPONSIBLE FOR ITS QPF...AND ASSOCIATED GRIDDED POPS FOR BEING FURTHER NORTH. BECAUSE OF THIS HAVE COLLABORATED WITH NEIGHBORING WFOS AND WPC TO PUSH GOING POPS FURTHER SOUTH INTO MAINLY SOUTH OF I-80 FOR MANY OF THOSE PERIODS. SO BASICALLY HAVE CHICAGO DRY TUESDAY THROUGH SUNDAY WITH A CHANCE FOR STORMS SOUTH...ESPECIALLY WEDNESDAY AND THURSDAY. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * LINGERING SHOWERS EARLY THIS MORNING...WITH POSSIBLE REDEVELOPMENT BY MID MORNING. * FOG THIS MORNING...WITH OUTSIDE POSSIBILITY FOR BRIEF IFR CEILINGS. * VARYING WIND EARLY THIS MORNING BECOMING NORTHEAST. RODRIGUEZ //DISCUSSION...UPDATED 06Z... COMPLEX FORECAST EARLY THIS MORNING OWING TO REMAINING SHOWERS...A RELAXED SURFACE PATTERN WITH LINGERING BOUNDARIES SITUATED ACROSS THE REGION...AND DEVELOPING FOG THIS MORNING. LATEST RADAR IMAGERY DEPICTING AREA OF PRECIP SLOWLY MOVING EAST THROUGH NORTHEAST ILLINOIS AND NORTHWEST INDIANA...AND EXPECT THIS SLOW TREND TO CONTINUE AND EXIT THE REMAINING TERMINALS OVER THE NEXT ONE TO THREE HOURS. VFR CEILINGS IN PLACE WITH THIS LIKELY TO CONTINUE BUT WITH THE ADDED MOISTURE AND RELAXED SURFACE PATTERN AS WELL AS SLOWLY CLEARING SKIES...LOWER CEILINGS COULD DEVELOP EARLY THIS MORNING. HAVE MORE CONFIDENCE WITH FOG DEVELOPING THAN THESE LOWER CEILINGS AND HAVE LEFT OUT ANY MENTION OF IFR CEILINGS IN THE TAF...BUT WILL NEED TO CONTINUE TO MONITOR TRENDS. LIKELY SCENARIO FOR PRECIP CHANCES FOR LATER THIS MORNING INTO MID DAY WOULD BE FOR ANY FURTHER DEVELOPMENT TO BE JUST SOUTH OF THE TERMINALS WITH GYY HAVING THE BEST CHANCES. WILL NEED TO MONITOR THIS AS WELL WITH SOME ISOLATED SHOWER DEVELOPMENT PERSISTING OVER NORTHWEST ILLINOIS AT THIS TIME...AND WITH SHORT TERM GUIDANCE HINTING AT THIS POSSIBILITY OVER THE REMAINING TERMINALS LATER THIS MORNING. WINDS WILL LIKELY CONTINUE TO VARY AS THIS PRECIP PUSHES THROUGH...BUT AM ANTICIPATING SPEEDS TO REMAIN UNDER 10KT. WINDS WILL THEN TURN TO THE NORTHEAST LATER THIS MORNING AND REMAIN THIS DIRECTION THROUGH THE REST OF THE FORECAST PERIOD. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM HIGH CONFIDENCE WITH SHOWER TRENDS EARLY THIS MORNING...LOW CONFIDENCE WITH POSSIBLE REDEVELOPMENT. * HIGH CONFIDENCE WITH FOG AND MEDIUM CONFIDENCE WITH VIS...LOW CONFIDENCE WITH ANY BRIEF IFR CEILINGS. * MEDIUM CONFIDENCE WITH WIND SPEED/DIRECTION. RODRIGUEZ //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY...SLIGHT CHANCE OF EVE TSRA. EAST-NORTHEAST WINDS. THURSDAY...SLIGHT CHANCE OF TSRA. EAST-NORTHEAST WINDS. FRIDAY-SATURDAY...VFR LIKELY. EAST WINDS. BEACHLER && .MARINE... 222 PM CDT WEAK HIGH PRESSURE REMAINS OVER THE REGION WHILE A COLD FRONT HAS STALLED OVER THE SOUTHERN END OF THE LAKE. WINDS ARE NORTH BEHIND THE FRONT AND THEN ONSHORE SOUTH OF THE FRONT. THE FRONT WILL RESUME ITS SOUTHERLY PUSH LATE TONIGHT AND CLEAR THE SOUTHERN END OF THE LAKE EARLY TUESDAY MORNING. WINDS WILL ALSO INCREASE TO 10-20 KT TOMORROW OVER THE SOUTHERN TWO THIRDS OF THE LAKE. WAVES CONTINUE TO REMAIN BELOW SMALL CRAFT ADVISORY CRITERIA. HIGH PRESSURE BUILDS IN BEHIND THE FRONT AND WINDS DIMINISH TUESDAY NIGHT TO 10-15 KT. THE HIGH REMAINS OVER THE LAKE THROUGH THE WEEKEND. NORTH TO NORTHEAST WINDS ARE EXPECTED THROUGH WEDNESDAY NIGHT. THEY THEN BECOME EAST THURSDAY NIGHT AND STAY THERE THROUGH THE WEEKEND AT 15 KT OR LESS. JEE && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1146 PM CDT Mon Aug 4 2014 .DISCUSSION... ISSUED 834 PM CDT Mon Aug 4 2014 Convection that developed west of the Illinois River very late afternoon has diminished some and made it as far east as I-155. A large area of showers and thunderstorms was along and north of a frontal boundary, which extended from near Des Moines into the Chicago metro. Main threat of storms the rest of the night will be most concentrated along and west of I-55, as a shortwave drops southeast across Iowa. May see a few showers/storms as far southeast as I-70 after midnight, but areas south of there likely to remain dry overnight. Updated zones/grids have been sent. Geelhart && .AVIATION... ISSUED 1137 PM CDT Mon Aug 4 2014 Showers and scattered storms continuing over central Illinois late Monday evening, most concentrated from KPIA southeast. The storms are likely to be out of the KPIA vicinity by the start of the TAF period, and will leave them out of there. KBMI, KCMI and KDEC also likely to see a period of these storms, and have gone with TEMPO groups for a couple hours to reduce visibility to around 2-3SM. Thunder threat around KSPI appears minimal. Have some concerns for visibility overnight, as a frontal boundary settles southward across northern Illinois. Latest satellite imagery showing some fairly substantial cloud breakup across Iowa and more sustained clearing further north in Minnesota. With the amount of rain that has fallen near KPIA Monday evening, any clearing with the light winds will cause visibilities to tank. Latest HRRR and RAP guidance focuses this more in Iowa and northwest Illinois. For now will include a TEMPO group at KPIA to bring visibility down to 3SM, but will need to watch this closely. Further east, the higher clouds should last longer into the night, and have kept visibility restrictions minimal for now. Later parts of the forecast mainly focus on a wind shift to the northwest and then north, as a cold front pushes through the area. Have maintained some VCTS mention at KCMI during the afternoon, with dry conditions elsewhere. Geelhart && .PREV DISCUSSION... ISSUED 236 PM CDT Mon Aug 4 2014 SHORT TERM...Today through Wednesday Northwesterly flow aloft over and upstream of Illinois as a large scale high pressure ridge resides over the Rockies and a large scale trough resides over the eastern U.S. just east of Illinois. Disturbances embedded in the northwesterly flow upstream of Illinois and a cold front currently near the IL/WI border will be the main features bringing precipitation/thunderstorms to central IL through Tuesday. SHORT TERM...Today through Wednesday. Frontal boundary to the north expected to move into central IL overnight and to southeast IL late Tuesday. Thunderstorm activity currently over southern WI will spread into central IL as this occurs, however daytime heating will have ended bringing limiting surface-based instability. Mid-upper level instability should still be enough for some elevated convection however. As the front moves to Southeast IL Tuesday afternoon, thunderstorm activity should shift to that region. A bit of a break is likely Tuesday evening, then another disturbance brings stronger mid-level flow over the region late Tuesday night along with precipitable water increasing to around 2 inches interacting with the frontal zone stalled over the region. This should bring another good chance for showers and thunderstorms through Wednesday, some with potentially heavy rainfall. Instability looks to be minimal so severe thunderstorm potential remains minimal, primarily over west-central IL. LONG TERM...Thursday through Monday. The frontal boundary is expected to linger for a few days, eventually pushing southward late in the week. As a result, chance PoPs remain in the forecast through Friday, gradually moving off to the south. A basically dry forecast is in store for the weekend with the frontal boundary moving to the south however models still indicate disturbances moving across the top of the ridge to the west could affect portions of western Illinois, and have kept slight chances in for this possibility. Onton && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
100 PM EDT TUE AUG 5 2014 .UPDATE... AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /REST OF TODAY/... ISSUED AT 929 AM EDT TUE AUG 5 2014 UPPED POPS TO LIKELY IN THE EXTREME WEST THIS MORNING BASED ON CURRENT RADAR TRENDS AND UPPED THEM TO HIGH END OF CHANCE CATEGORY FOR MUCH OF THE REMAINDER OF THE WEST. RAIN IS GENERALLY DIMINISHING AS IT MOVES EAST SO KEPT LOWER POPS EAST. AS UPPER WAVE MOVES EAST LATER THIS MORNING SUPPORT FOR CONVECTION WEAKENS...AND LATEST HI RES MODELS ARE SHOWING LITTLE DEVELOPMENT THIS AFTERNOON. HOWEVER STILL THINK POTENTIAL IS THERE FOR SCATTERED DEVELOPMENT WITH THE EXPECTED AFTERNOON INSTABILITY. THUS GENERALLY KEPT POPS THE SAME THIS AFTERNOON...BUT LOWERED JUST A BIT FROM THE HIGH END CHANCE CATEGORY NORTHEAST DUE TO THE WEAKER SUPPORT. PREVIOUS DISCUSSION FOLLOWS... RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR 051800Z TAF ISSUANCE/... ISSUED AT 100 PM EDT TUE AUG 5 2014 MOSTLY VFR THROUGH THE PERIOD. ALTHOUGH A PERIOD OF MVFR CEILINGS AND FOG NOT OUT OF THE QUESTION LATE TONIGHT AND EARLY WEDNESDAY. A WEAK COLD FRONT OVER NORTHERN INDIANA WILL DRIFT SOUTH ACROSS OUR REGION TONIGHT AND TO NEAR THE OHIO RIVER WEDNESDAY. HIGH PRESSURE WILL BUILD INTO THE GREAT LAKES WEDNESDAY. WEATHER DEPICTION INDICATES AREAS OF MVFR CEILINGS ASSOCIATED WITH THE COLD FRONT OVER NORTHERN ILLINOIS AND SOUTHERN GREAT LAKES. HOWEVER MODEL SOUNDINGS DO NOT INDICATE THIS WILL SPREAD INTO OUR REGION TONIGHT. NERVELESS I WOULD NOT RULE OUT THAT THESE CEILINGS WILL SPREAD INTO OUR REGION. FOR NOW WILL BRING IN 2 THOUSAND SCATTERED WITH MVFR FOG LATE TONIGHT. ON WEDNESDAY EXPECT VFR CONDITIONS FROM MID MORNING ON. A WIDELY SCATTERED THUNDERSHOWER POSSIBLE THROUGH THIS EVENING AND AGAIN WEDNESDAY...BUT CHANCE OF OCCURRENCE TOO LOW TO EVEN MENTION VCTS IN TAFS. WEST OR SOUTHWEST WINDS AROUND 6 KNOTS WILL BECOME LIGHT TONIGHT AND NORTH TO NORTHWEST UP TO 8 KNOTS WEDNESDAY. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP/50 SHORT TERM...CP LONG TERM....RYAN AVIATION...JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1025 AM EDT TUE AUG 5 2014 .UPDATE... AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /REST OF TODAY/... ISSUED AT 929 AM EDT TUE AUG 5 2014 UPPED POPS TO LIKELY IN THE EXTREME WEST THIS MORNING BASED ON CURRENT RADAR TRENDS AND UPPED THEM TO HIGH END OF CHANCE CATEGORY FOR MUCH OF THE REMAINDER OF THE WEST. RAIN IS GENERALLY DIMINISHING AS IT MOVES EAST SO KEPT LOWER POPS EAST. AS UPPER WAVE MOVES EAST LATER THIS MORNING SUPPORT FOR CONVECTION WEAKENS...AND LATEST HI RES MODELS ARE SHOWING LITTLE DEVELOPMENT THIS AFTERNOON. HOWEVER STILL THINK POTENTIAL IS THERE FOR SCATTERED DEVELOPMENT WITH THE EXPECTED AFTERNOON INSTABILITY. THUS GENERALLY KEPT POPS THE SAME THIS AFTERNOON...BUT LOWERED JUST A BIT FROM THE HIGH END CHANCE CATEGORY NORTHEAST DUE TO THE WEAKER SUPPORT. PREVIOUS DISCUSSION FOLLOWS... RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR 051500Z KIND TAF UPDATE/... ISSUED AT 1025 AM EDT TUE AUG 5 2014 MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS. NO OTHER CHANGES NEEDED AT THIS PORINT. PREVIOUS AVIATION DISCUSSION FOLLOWS... MVFR CONDITIONS POSSIBLE LATE TONIGHT...OTHERWISE VFR EXPECTED. WEAKENING AREA OF SHOWERS PROGRESSING INTO THE REGION THIS MORNING MAY BRIEFLY IMPACT ALL BUT KLAF. SHORT RANGE MODEL GUIDANCE CONTINUES TO WEAKEN AND DIMINISH THE PRECIP AREA BY LATE MORNING. EXPECT VFR CU DEVELOPMENT THIS AFTERNOON ALONG WITH SCATTERED CONVECTION AS A WEAK FRONTAL BOUNDARY DROPS INTO CENTRAL INDIANA. WILL CARRY VCTS AT KLAF THROUGH THE AFTERNOON WHERE FORCING ALOFT IS SOMEWHAT BETTER. CONFIDENCE IN CONVECTIVE TIMING AND COVERAGE REMAINS HIGHLY UNCERTAIN AT THE OTHER TERMINALS AND WILL KEEP THESE SITES DRY AT THIS TIME. SOUTHWEST WINDS AT 5 TO 10KTS EXPECTED THIS AFTERNOON. WINDS WILL BECOME LIGHT TONIGHT AS THEY VEER TO N/NW BEHIND THE BOUNDARY. MODEL SOUNDINGS INDICATING MID LEVEL CLOUDS LIKELY TO BECOME THE PREDOMINANT DECK AS THE NIGHT PROGRESSES WITH SLIGHTLY DRIER AIR WITHIN THE BOUNDARY LAYER NORTH OF THE BOUNDARY. COULD SEE MVFR FOG DEVELOP AT OUTLYING TERMINALS LATE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP/50 SHORT TERM...CP LONG TERM....RYAN AVIATION...RYAN/JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
929 AM EDT TUE AUG 5 2014 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /REST OF TODAY/... ISSUED AT 929 AM EDT TUE AUG 5 2014 UPPED POPS TO LIKELY IN THE EXTREME WEST THIS MORNING BASED ON CURRENT RADAR TRENDS AND UPPED THEM TO HIGH END OF CHANCE CATEGORY FOR MUCH OF THE REMAINDER OF THE WEST. RAIN IS GENERALLY DIMINISHING AS IT MOVES EAST SO KEPT LOWER POPS EAST. AS UPPER WAVE MOVES EAST LATER THIS MORNING SUPPORT FOR CONVECTION WEAKENS...AND LATEST HI RES MODELS ARE SHOWING LITTLE DEVELOPMENT THIS AFTERNOON. HOWEVER STILL THINK POTENTIAL IS THERE FOR SCATTERED DEVELOPMENT WITH THE EXPECTED AFTERNOON INSTABILITY. THUS GENERALLY KEPT POPS THE SAME THIS AFTERNOON...BUT LOWERED JUST A BIT FROM THE HIGH END CHANCE CATEGORY NORTHEAST DUE TO THE WEAKER SUPPORT. PREVIOUS DISCUSSION FOLLOWS... RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR 051200Z TAF ISSUANCE/... ISSUED AT 628 AM EDT TUE AUG 5 2014 MVFR CONDITIONS POSSIBLE LATE TONIGHT...OTHERWISE VFR EXPECTED. WEAKENING AREA OF SHOWERS PROGRESSING INTO THE REGION THIS MORNING MAY BRIEFLY IMPACT ALL BUT KLAF. SHORT RANGE MODEL GUIDANCE CONTINUES TO WEAKEN AND DIMINISH THE PRECIP AREA BY LATE MORNING. EXPECT VFR CU DEVELOPMENT THIS AFTERNOON ALONG WITH SCATTERED CONVECTION AS A WEAK FRONTAL BOUNDARY DROPS INTO CENTRAL INDIANA. WILL CARRY VCTS AT KLAF THROUGH THE AFTERNOON WHERE FORCING ALOFT IS SOMEWHAT BETTER. CONFIDENCE IN CONVECTIVE TIMING AND COVERAGE REMAINS HIGHLY UNCERTAIN AT THE OTHER TERMINALS AND WILL KEEP THESE SITES DRY AT THIS TIME. SOUTHWEST WINDS AT 5 TO 10KTS EXPECTED THIS AFTERNOON. WINDS WILL BECOME LIGHT TONIGHT AS THEY VEER TO N/NW BEHIND THE BOUNDARY. MODEL SOUNDINGS INDICATING MID LEVEL CLOUDS LIKELY TO BECOME THE PREDOMINANT DECK AS THE NIGHT PROGRESSES WITH SLIGHTLY DRIER AIR WITHIN THE BOUNDARY LAYER NORTH OF THE BOUNDARY. COULD SEE MVFR FOG DEVELOP AT OUTLYING TERMINALS LATE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP/50 SHORT TERM...CP LONG TERM....RYAN AVIATION...RYAN VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
628 AM EDT TUE AUG 5 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /TODAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR 051200Z TAF ISSUANCE/... ISSUED AT 628 AM EDT TUE AUG 5 2014 MVFR CONDITIONS POSSIBLE LATE TONIGHT...OTHERWISE VFR EXPECTED. WEAKENING AREA OF SHOWERS PROGRESSING INTO THE REGION THIS MORNING MAY BRIEFLY IMPACT ALL BUT KLAF. SHORT RANGE MODEL GUIDANCE CONTINUES TO WEAKEN AND DIMINISH THE PRECIP AREA BY LATE MORNING. EXPECT VFR CU DEVELOPMENT THIS AFTERNOON ALONG WITH SCATTERED CONVECTION AS A WEAK FRONTAL BOUNDARY DROPS INTO CENTRAL INDIANA. WILL CARRY VCTS AT KLAF THROUGH THE AFTERNOON WHERE FORCING ALOFT IS SOMEWHAT BETTER. CONFIDENCE IN CONVECTIVE TIMING AND COVERAGE REMAINS HIGHLY UNCERTAIN AT THE OTHER TERMINALS AND WILL KEEP THESE SITES DRY AT THIS TIME. SOUTHWEST WINDS AT 5 TO 10KTS EXPECTED THIS AFTERNOON. WINDS WILL BECOME LIGHT TONIGHT AS THEY VEER TO N/NW BEHIND THE BOUNDARY. MODEL SOUNDINGS INDICATING MID LEVEL CLOUDS LIKELY TO BECOME THE PREDOMINANT DECK AS THE NIGHT PROGRESSES WITH SLIGHTLY DRIER AIR WITHIN THE BOUNDARY LAYER NORTH OF THE BOUNDARY. COULD SEE MVFR FOG DEVELOP AT OUTLYING TERMINALS LATE. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...RYAN VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
452 AM EDT TUE AUG 5 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /TODAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR THE 050900Z TAF UPDATE/... ISSUED AT 452 AM EDT TUE AUG 5 2014 ONLY MINOR CHANGES NEEDED TO THE FIRST FEW HOURS OF THE FORECASTS BASED ON CURRENT OBS. CONVECTION CONTINUES TO WEAKEN AND DIMINISH IN COVERAGE AS IT MOVES INTO OUR NORTHWEST COUNTIES...BUT MAY STILL PRODUCE A FEW SHOWERS IN THE VICINITY OF THE KLAF TERMINAL OVER THE NEXT FEW HOURS. 06Z DISCUSSION FOLLOWS. VFR THROUGH MUCH OF THE PERIOD...WITH SOME MVFR FOG POSSIBLE AT MAINLY THE OUTLYING SITES NEAR DAYBREAK. WINDS HAVE BECOME LIGHT TO CALM AND DEWPOINTS HIGH AGAIN TONIGHT. HOWEVER...SOME DEBRIS CLOUDINESS FROM UPSTREAM MAY BE A COMPLICATING FACTOR. WILL TAKE OUTLYING SITES DOWN TO MVFR AFTER ABOUT 08-09Z. ANY FOG WILL BURN OFF IN TYPICAL DIURNAL FASHION TUESDAY MORNING. CANNOT COMPLETELY RULE OUT A FEW STORMS NEAR LAF AND AT MOST SITES TUESDAY...BUT PROBABILITIES AND TOO LOW AND TIMING/PLACEMENT TOO UNCERTAIN FOR INCLUSION. WILL INCLUDE VCSH AT LAF FOR THE UPSTREAM CONVECTION THAT MAY BRUSH THE LAF AREA AS IT IS DISSIPATING. WINDS WILL BE BELOW 10KT THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...NIELD/RYAN VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
410 AM EDT TUE AUG 5 2014 .UPDATE... THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 359 AM EDT TUE AUG 5 2014 A COLD FRONT MOVING INTO THE AREA WILL BRING CHANCES FOR THUNDERSTORMS TO CENTRAL INDIANA TODAY. THIS FRONT WILL STALL SOMEWHERE IN THE AREA AND UPPER WAVES WILL INTERACT WITH IT THROUGH THE REST OF THE WEEK KEEPING THUNDERSTORM CHANCES IN THE FORECAST. NEAR NORMAL TEMPERATURES WILL TAKE A SMALL DIP IN THE WAKE OF THE COLD FRONTAL PASSAGE WEDNESDAY AND THURSDAY BEFORE REBOUNDING TO NORMAL FROM THURSDAY ON. && .NEAR TERM /TODAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 RADAR MOSAIC SHOWS SHOWERS AND THUNDERSTORMS MOVING INTO THE NORTHWESTERN COUNTIES BUT SHRINKING AS THEY DO. THESE WILL SLOWLY MOVE IN BUT COVERAGE WILL BE LESS AND LESS BASED ON CURRENT TRENDS. THUS KEPT POPS AT CHANCE/SCATTERED OR LESS FOR THE REST OF THE EARLY MORNING. AFTER THAT SHORT TERM MODELS ARE SHOWING EVEN LESS COVERAGE BUT PERHAPS AN INCREASE AGAIN IN THE AFTERNOON. TRIED TO TIME THE POPS FOR THE TODAY PERIOD WITH THE MOVEMENT OF THE UPPER WAVE AND KEPT THE HIGHEST POPS ACROSS THE NORTH. BROUGHT A SLIGHT CHANCE IN ACROSS THE SOUTH FOR THE AFTERNOON INSTEAD OF KEEPING THINGS DRY WITH RAP SHOWING SOME DEVELOPMENT THERE AS WELL BUT THE BEST FORCING STAYING FAR FROM THERE. FOR TEMPERATURES THOUGHT THE CONSENSUS NUMBERS DID A GOOD JOB. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 359 AM EDT TUE AUG 5 2014 FOR TONIGHT CONTINUED WITH SOME POPS AS A CARRYOVER FROM TODAY AS THE UPPER WAVE WILL BE MOVING OUT. BY LATE TONIGHT WENT DRY WITH LITTLE FORCING PRESENT. FOR WEDNESDAY MODELS HAVE TRENDED DRIER THIS RUN. NOT READY TO BUY THIS FULL ON SINCE LAST NIGHT/S RUNS HAD WEDNESDAY LOOKING FAIRLY WET. THUS BLENDED PREVIOUS AND CURRENT SOLUTIONS TO PROVIDE A COMPROMISE OF LOW CHANCE POPS ACROSS THE AREA. THE BEST FORCING WILL NOT BE ARRIVING UNTIL VERY LATE WEDNESDAY NIGHT INTO THURSDAY WITH A SHORTWAVE PROVIDING ADDITIONAL FORCING TO THE FRONT WHOSE EXACT POSITION IS STILL VARIABLE BETWEEN MODELS AND RUN-TO-RUN. WENT WITH THE HIGHEST POPS IN THE PERIOD ON THURSDAY WITH THE FORCING FROM THE UPPER WAVE. IF THE SURFACE FRONT SETS UP JUST TO THE SOUTH OR RIGHT ACROSS THE AREA HEAVY RAIN COULD BE A PROBLEM...BUT AT THIS POINT THE EXACT LOCATION OF THAT FRONT IS STILL VERY LOW CONFIDENCE. FOR TEMPERATURES THROUGH THE PERIOD GENERALLY USED A CONSENSUS. FOR THURSDAY/S HIGHS THOUGH WENT LOWER THAN THE MODEL AVERAGE TO REFLECT THE POTENTIAL FOR COOLER TEMPERATURES WITH THE HIGHER PROBABILITY FOR CLOUD COVER AND RAIN. && .LONG TERM /FRIDAY THROUGH MONDAY/... ISSUED AT 359 AM EDT TUE AUG 5 2014 THE THREAT FOR UNSETTLED WEATHER IS LIKELY TO PERSIST INTO THE WEEKEND AS NORTHWEST FLOW ALOFT REMAINS ACROSS THE REGION AND A FRONTAL BOUNDARY ALIGNS OVER THE TENNESSEE AND LOWER OHIO VALLEYS. 00Z MODEL SUITE HAS SHIFTED THE FRONT FURTHER NORTH FROM PREVIOUS RUNS...ESPECIALLY THE ECMWF AND OP GFS WHICH BOTH HAD MAINTAINED A MORE SUPPRESSED LOCATION TO THE BOUNDARY. DIFFERENCES REMAIN HOWEVER WITH RESPECT TO EVENTUAL LOCATION OF THE BOUNDARY BUT WITH A GENERAL CONSENSUS NOW PLACING IT JUST SOUTH OF THE REGION...CARRYING PRECIP CHANCES REMAINS WARRANTED INTO THE FIRST HALF OF THE WEEKEND. WILL PLACE HIGHEST POPS FRIDAY INTO EARLY SATURDAY OVER SOUTHERN COUNTIES AS A SURFACE WAVE RIDES ALONG THE BOUNDARY. WITH A DEEP MOIST AIRMASS IN PLACE FRIDAY/SATURDAY...HEAVY RAIN IS LIKELY TO ACCOMPANY STORMS. DRIER AIR ATTEMPTS TO MAKE A BRIEF APPEARANCE SATURDAY NIGHT WITH HIGH PRESSURE OVER THE NORTHERN GREAT LAKES...BUT THE ARRIVAL OF ADDITIONAL WAVES ALOFT AND THE REMNANT BOUNDARY LINGERING IN THE OHIO VALLEY SUPPORTS REINTRODUCING POPS INTO EARLY NEXT WEEK. TEMPERATURES WILL REMAIN SEASONABLE BUT CONTINUE TO RUN SLIGHTLY BELOW NORMAL THROUGH THE EXTENDED...WITH HIGHS RANGING FROM THE UPPER 70S TO MIDDLE 80S. && .AVIATION /DISCUSSION FOR THE 05/06Z TAFS/... ISSUED AT 1238 AM EDT TUE AUG 5 2014 VFR THROUGH MUCH OF THE PERIOD...WITH SOME MVFR FOG POSSIBLE AT MAINLY THE OUTLYING SITES NEAR DAYBREAK. WINDS HAVE BECOME LIGHT TO CALM AND DEWPOINTS HIGH AGAIN TONIGHT. HOWEVER...SOME DEBRIS CLOUDINESS FROM UPSTREAM MAY BE A COMPLICATING FACTOR. WILL TAKE OUTLYING SITES DOWN TO MVFR AFTER ABOUT 08-09Z. ANY FOG WILL BURN OFF IN TYPICAL DIURNAL FASHION TUESDAY MORNING. CANNOT COMPLETELY RULE OUT A FEW STORMS NEAR LAF AND AT MOST SITES TUESDAY...BUT PROBABILITIES AND TOO LOW AND TIMING/PLACEMENT TOO UNCERTAIN FOR INCLUSION. WILL INCLUDE VCSH AT LAF FOR THE UPSTREAM CONVECTION THAT MAY BRUSH THE LAF AREA AS IT IS DISSIPATING. WINDS WILL BE BELOW 10KT THROUGHOUT THE PERIOD. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CP NEAR TERM...CP SHORT TERM...CP LONG TERM....RYAN AVIATION...NIELD VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
633 PM CDT WED AUG 6 2014 .SHORT TERM /TONIGHT/... ISSUED AT 328 PM CDT WED AUG 6 2014 ANOTHER ROUND OF HEAVY RAINFALL IS POSSIBLE FOR THE CWA TONIGHT...MAINLY SOUTHERN PORTIONS. TWO SHORTWAVES...PRESENTLY MOVING THROUGH SE SOUTH DAKOTA AND NORTH CENTRAL KS...WILL HELP PROVIDE THE LARGE-SCALE FORCING FOR OVERNIGHT PCPN. LLJ IS EXPECTED TO DEVELOP AGAIN TONIGHT AND POINT INTO IA...PROVIDING AMPLE MOISTURE. PWATS ARE PROGGED TO BE INVOF THE 2.0 IN RANGE...WHICH AGAIN WILL BE AROUND +2 SD VS CLIMO. WARM CLOUD DEPTHS WILL APPROACH THE 12 KFT RANGE. MODEL FCST SOUNDINGS DO TEND TO MOISTEN THE COLUMN ACROSS SOUTHERN IA THIS EVENING...MORE SO THAN LAST NIGHT...WHICH WOULD TEND TO SUPPORT THE HEAVY RAIN THREAT TONIGHT. MODEL SOLUTIONS DO VARY ON THE AMOUNT OF FORCING AND RESULTING RAINFALL. THE NAM IS THE WETTEST AND BRINGS A RIBBON OF FORCING ALONG WITH STRONG THETA-E ADVECTION INTO SOUTH CENTRAL AND SOUTHWEST IA. THE GFS ON THE OTHER HAND IS NOT AS INTENSE THAT FAR NORTH. HAVE TENDED TO SPLIT THE DIFFERENCE...AND EXPECT THE HEAVIEST RAINFALL TONIGHT TO REMAIN SOUTH OF IA HWY 92. WILL GO WITH A FLASH FLOOD WATCH FOR SOME OF THE SOUTH CENTRAL AND SOUTHWEST IA COUNTIES ALONG AND SOUTH OF 92...GIVEN LAST NIGHT/S HEAVY RAINFALL AND RELATIVELY LOWER FLASH FLOOD GUIDANCE VALUES. ALTHOUGH AM NOT OVERLY CONCERNED ABOUT FLASH FLOOD POTENTIAL THERE...CONFIDENCE IS AROUND THE 40 TO 50 PERCENT THRESHOLD WHICH WOULD BE THE LOW-END FLASH FLOOD WATCH CRITERIA. SEVERE WEATHER POTENTIAL THIS EVENING AND OVERNIGHT IS MINIMAL BUT CANNOT BE ENTIRELY RULED OUT. ALTHOUGH CAPE VALUES HAVE INCREASED THIS AFTN IN SW IA...WITH VALUES APPROACHING THE 1000 TO 1500 J/KG RANGE. DEEP-LAYER SHEAR IS MINIMAL HOWEVER...WHICH WOULD TEND TO PRECLUDE ORGANIZED TSTM DEVELOPMENT. ATTM ANTICIPATE THE GREATEST THREAT WOULD BE HEAVY RAINFALL FROM ANY STORMS THAT DO DEVELOP. .LONG TERM /THURSDAY THROUGH WEDNESDAY/... ISSUED AT 328 PM CDT WED AUG 6 2014 MAIN CHALLENGES THIS PERIOD WILL BE MAINLY IN THE SHORTER TERM WITH EVOLUTION OF SYSTEM NEXT 24 HOURS. CURRENTLY SFC SHORT WAVE SOUTH OF THE AREA WITH BOUNDARY OVER NORTHERN MO AND WEAK TROUGH EXTENDING ACROSS NORTH CENTRAL IOWA WITH WELL DEFINED DEFORMATION AXIS AND THETAE AXIS ALOFT ACROSS THE REGION. ISENTROPIC UPGLIDE CONTINUES TO FEED THIS AREA WHERE PERSISTENT LIGHT RAIN IS FALLING. MODELS HAVENT QUITE REACHED A CONSENSUS ON THE EVENTUAL DEPARTURE OF THE SYSTEM FOR THURSDAY/THURSDAY NIGHT. THIS IS IN PART DUE TO THE PERSISTENT RIDGE AXIS WHICH EXTENDS FROM SOUTHERN CANADA TO THE SOUTHEAST US. THE GENERAL TREND HAS BEEN FOR A SLOWER TRANSITION OUT OF THE AREA THURSDAY INTO THURSDAY NIGHT. THURSDAY MORNING MOST OF THE FORCING WILL REMAIN STRONGEST ACROSS THE SOUTHEAST WITH CONTINUED UPGLIDE WRAPPING AROUND THE SYSTEM BACK INTO CENTRAL AND NORTHERN IOWA DURING THE DAY. THOUGH THE H850 MOISTURE CHANNEL WILL GRADUALLY SHIFT TO THE EAST WITH TIME...LIGHT TO MODERATE RAIN SHOULD CONTINUE THROUGH MUCH OF THE DAY THURSDAY THEN SLOWLY TAPER OFF DURING THE EVENING HOURS. BOTH THE EURO/GFS/NAM HIT THE EAST/SOUTHEAST WITH QUITE A BIT OF QPF FOCUSED BETWEEN 12-18Z USING A SLIGHTLY FARTHER NORTH TRACK OF THE H850 LOW. WPC CONTINUES TO PREFER A MORE SOUTHERN SOLUTION MORE IN LINE WITH MESO HRRR AND NMM MODELS. CURRENTLY THE SYSTEM IS TRACKING FAIRLY WELL WITH ALL MODELS BUT WITH EXPECTED MESO CONVECTION TO DEVELOP OVER NORTHERN MO THIS EVENING...TRACK EXPECTED TO END UP BEING FARTHER SOUTH THAN SYNOPTIC MODELS INDICATE AND CLOSER TO THE HRRR/NMM. FOR NOW WILL TREND TOWARD THAT SOLUTION ...IN LINE WITH WPC AS WELL BUT WILL NEED TO WATCH DURING THE EVENING SHIFT FOR ANY POTENTIAL ADJUSTMENTS FARTHER NORTH. ANY DEVIATION NORTH WOULD RESULT IN RAINFALL TOTALS BEING HIGHER IN THE FORECAST AREA THURSDAY. EVENTUALLY THE SYSTEM BECOMES SHEARED OUT AND WEAKENS...AND HANGS ON INTO FRIDAY WITH LINGERING SHOWERS OR ISO THUNDER OVER THE SOUTH. ALREADY INTO THE WEEKEND NOW SOME UNCERTAINTY REGARDING THE NEXT UPSTREAM WAVE APPROACHING FROM THE WEST FOR SATURDAY AND SUNDAY. GREAT LAKES HIGH NOW BEING MODELED TO STRENGTHEN OVER THE REGION AND IS NOW TRENDING TO KEEP AREA DRIER THAN PREVIOUSLY FORECAST. HAVE REDUCED POP CHANCES FOR BOTH DAYS... BUT HAVE NOT CUT OUT YET DUE TO CONFIDENCE CONCERNS AND CONSENSUS WITH NEIGHBORING OFFICES AT THIS POINT. IF TRENDS CONTINUE WITH TONIGHTS MODEL PACKAGES...THEN FURTHER REDUCTION IN RAIN CHANCES WILL BE WARRANTED. TEMPERATURES WILL REMAIN COOL THURSDAY WITH EXTENSIVE CLOUD COVER AND SHOWERS. BY FRIDAY SOME MODERATION IS EXPECTED WHICH SHOULD CONTINUE INTO THE WEEKEND. NORTHEAST FLOW WILL DEVELOP BY THURSDAY AFTERNOON AND CONTINUE THROUGH FRIDAY WITH SOME RISK FOR PATCHY FOG OVERNIGHT AS CLOUDS AND HIGH MOISTURE REMAINS IN THE BOUNDARY LAYER. LOOKING AHEAD TO NEXT WEEK....LESSENING CHANCES FOR RAIN WILL CONTINUE THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE REMAINS IN THE AREA. SOME HINT AT RETURN MOISTURE BY NEXT WEDNESDAY AS A TROUGH DEVELOPS OVER THE HIGH PLAINS AND MOVES INTO THE CENTRAL PLAINS. && .AVIATION...07/00Z ISSUED AT 629 PM CDT WED AUG 6 2014 SURFACE LOW WILL TRACK EAST TONIGHT ACROSS MISSOURI WITH EASTERLY LOW LEVEL FLOW ACROSS IOWA. BAND OF RAIN ACROSS CENTRAL IOWA WILL CONTINUE TO SLIDE EAST THIS EVENING. EASTERLY FLOW WILL CONTINUE THROUGH THE FORECAST PERIOD WITH ABUNDANT MOISTURE. EXPECT IFR/MVFR CIGS MUCH OF THE TIME IN CENTRAL AND SOUTHERN IOWA. THE NORTHERN TAFS MAY BE VFR MUCH OF THE TIME WITH DRIER AIR IN THE PART OF THE STATE. && .HYDROLOGY... ISSUED AT 328 PM CDT WED AUG 6 2014 THREAT OF HEAVY RAINS WILL PERSIST THROUGH TODAY THURSDAY WITH AMPLE MOISTURE IN PLACE BEING TRANSPORTED INTO THE STATE. URBAN AREAS WOULD BE MOST LIKELY TO EXPERIENCE ANY FLOODING ISSUES AS MOST RURAL LOCATIONS HAVE DRY ANTECEDENT CONDITIONS. MINIMAL RISES ARE ANTICIPATED ON AREA RIVERS. && .DMX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH THROUGH THURSDAY MORNING FOR ADAIR-CLARKE- DECATUR-LUCAS-MADISON-RINGGOLD-UNION-WAYNE. && $$ SHORT TERM...ZOGG LONG TERM...REV AVIATION...JOHNSON HYDROLOGY...ZOGG
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
311 PM CDT Tue Aug 5 2014 ...Updated Short Term section... .SHORT TERM...(This evening through Wednesday) ISSUED AT 309 PM CDT TUE AUG 5 2014 The primary focus will be convection this evening and how expansive it will be this evening across western Kansas. Water vapor loop early this afternoon showed a substantial mid level dry intrusion into the southwestern CONUS which was pushing northeastward through Colorado. RAP analysis revealed a fairly perturbed middle troposphere from the primary vorticity anomaly across central/northern California...eastward through Utah and into Colorado. A 250mb jet streak continued to nose northeastward into southern California through southern Utah. A lee trough convergence axis was found across far southeastern Colorado into far northwestern Kansas. This was on the western periphery of deep mid level moisture plume. All the short-term high resolution models suggest convection continuing to develop along the lee trough convergence axis and also over terrain-favored regions of Colorado. There is the suggestion that the most organized of lee trough convection will stay just north of the DDC forecast area from far west-central KS into northwestern KS. Both the 12Z WRF ARW and NMMB show a cluster of pseudo-organized convection rolling east-southeast reaching roughly a Leoti to Gove line by around 06Z. The best of the lee trough convergence will be farther north, so it would make sense that the high resolution models are keeping the most sustained convection across northwestern Kansas. Other less organized convection farther south may last through sunset, but not much after that. We will keep Chance POPs confined to far west-central KS (Kearny to Scott County). South winds tonight averaging 12 to 15 knots will keep the boundary layer mixed enough through the night that temperatures will likely plateau during the 06-12Z time frame in the lower 70s along/east of Highway 283. The trough axis will shift east Wednesday with lighter winds much of the day across much of southwest Kansas. Weak convergence along the trough may yield late afternoon convection, but only loosely organized convection at best can be expected with the deep frontogenetic forcing still north of the southwest Kansas region through late afternoon Wednesday. .LONG TERM...(Wednesday night through Tuesday) ISSUED AT 246 PM CDT TUE AUG 5 2014 No significant changes were made to the extended period of the forecast. Wednesday night, and through the overnight into Thursday morning will present chances for convection along a weak boundary and area of surface low pressure over western Kansas. The model signals for this suggest the best chances for isolated to scattered thunderstorms will be across central Kansas where instability and CAPE will be greater. Any storms along this convergence zone should end by Thursday morning across the south central Kansas counties rendering Thursday dry for most of the day. Convection will again be possible in the far west on Thursday evening and through the night as it forms diurnally along the high terrain of eastern Colorado with the aid of upslope surface flow and higher dew points around 60 degrees or more. Beyond Friday, the region will remain in a fairly westerly zonal pattern but also not a particularly strong surface gradient, leading to relatively light winds. As the region will remain fairly rich ion surface moisture and warm, any local areas of uncapped convergence could set off afternoon convection lasting into the very early evening through about Tuesday. However chances as far as areal coverage are concerned should be fairly minimal. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1202 PM CDT TUE AUG 5 2014 South winds will remain fairly strong through the afternoon, averaging 18 to 22 knots sustained through early evening before decreasing to around 12 to 15 knots later this evening. A fairly strong pressure gradient by summer standards will persist through the night, keeping surface winds up around 15 knots at HYS and DDC. The latest indications from high-resolution short term models is that loosely organized thunderstorms late this afternoon/evening will move slowly through west-central Kansas during the mid to late evening hours, but weaken or dissolve entirely late tonight. It does not seem likely that convection will impact any of the terminals, except perhaps GCK (being farther west). && .PRELIMINARY POINT TEMPS/POPS... DDC 69 94 67 92 / 10 20 20 10 GCK 67 94 66 92 / 20 20 20 10 EHA 67 94 66 95 / 20 10 10 20 LBL 69 95 68 97 / 10 20 20 10 HYS 70 96 67 93 / 30 20 30 10 P28 71 94 70 95 / 10 20 30 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Umscheid LONG TERM...Russell AVIATION...Umscheid
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1237 AM CDT Tue Aug 5 2014 ...Updated aviation discussion... .SYNOPSIS... ISSUED AT 349 PM CDT MON AUG 4 2014 Cirrus was slowly overspreading the western sections of Kansas from the mean height ridge moving eastward from the Rockies into the High Plains. A weak surface pressure/850 mb height gradient enveloped the Central Plains. Relative low pressure over the eastern Colorado resulted in a northward oriented pressure gradient gradient across western Kansas resulting in generally south winds at most locations with little downslope. Temperatures warmed to around 90 degrees across in most locations as dew points mixed down to the upper 40s from Scott City to Hugoton. Hays, which is closer to the warmer air at 850 mb warmed into the upper 90s. && .SHORT TERM...(This evening through Tuesday) ISSUED AT 349 PM CDT MON AUG 4 2014 The temperature trend and dew points to a lesser degree seemed to have followed the consensus of the short term models blend fairly well this afternoon. This trend will continue to be followed into the rest of the forecast including Tuesday morning and into Tuesday. The cirrus overhead may have a small impact on overnight lows as the recent updates have bumped lows into the mid and upper 60s in most locations. The HRRR model continues to show isolated to widely scattered convection across south central Kansas late this afternoon likely based on reaching convective temperatures. Current trends suggest this is overdone as was the case Sunday afternoon, and PoPs will not be added at this time. No major shift in airmass is taking place tonight and the same general pattern of surface winds and diurnal warming is expected heading into Tuesday afternoon. A breakdown in the ridge by a mid level shortwave will create scattered convection across northeast and east central Colorado by late in the afternoon. Low PoPs will be included for about the western half of the area starting at about about 23 UTC, following previous forecasts. .LONG TERM...(Tuesday night through Monday) ISSUED AT 341 PM CDT MON AUG 4 2014 The upper level ridge will flatten out and be shunted southward during the next couple of days as a series of upper level shortwaves move up and over the ridge. These features will bring a chance of thunderstorms to the forecast area through this weekend. The slight chance of thunderstorms will start out across far western Kansas Tuesday night then across central Kansas Wednesday night. Otherwise expect partly cloudy skies. Winds will generally be from the south to south southwest Tuesday night through Thursday with a surface trough located across eastern Colorado and far western Kansas. A better chance of thunderstorms will be expected this weekend as the upper level ridge retrogrades towards the southwest United States. Winds will generally be from the southeast during this time frame as a stationary front will be located at the surface south of the area with a dome of high pressure to the north. Highs through the extended period will generally be in the low to mid 90s with lows in the upper 60s and lower 70s. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1236 AM CDT TUE AUG 5 2014 VFR conditions will prevail through this TAF period. South winds will generally be around 10 knots or less overnight but are expected to become a little more southwesterly and increase to around 15-20 knots with higher gusts by mid to late morning Tuesday. Isolated to widely scattered thunderstorms could impact the Garden City and Dodge City airports toward the end of this TAF period. Given the timing and expected nature of the storms, will hold off putting any mention of storms in the TAFs at this time. && .PRELIMINARY POINT TEMPS/POPS... DDC 69 95 68 93 / 20 20 20 10 GCK 68 94 67 92 / 20 20 10 20 EHA 67 95 67 94 / 20 10 10 20 LBL 69 96 68 95 / 20 10 10 10 HYS 70 94 68 91 / 20 30 30 20 P28 71 94 71 95 / 20 30 30 10 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...Russell SHORT TERM...Russell LONG TERM...Hovorka_42 AVIATION...Gerard
AREA FORECAST DISCUSSION
NWS GAYLORD MI
110 PM EDT TUE AUG 5 2014 .SYNOPSIS... ISSUED AT 357 AM EDT TUE AUG 5 2014 ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE IN INTERIOR AREAS OF NORTHERN LOWER MICHIGAN THIS AFTERNOON AND EVENING. HIGH PRESSURE WILL THEN SETTLE IN OVER THE GREAT LAKES REGION WEDNESDAY. THIS HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S EACH DAY WITH LOWS GENERALLY IN THE 50S. && .UPDATE... ISSUED AT 1024 AM EDT TUE AUG 5 2014 A NICE EARLY AUGUST DAY UNFOLDING ACROSS THE AREA...WITH THE PASSAGE OF A SHORTWAVE TROUGH BRINGING AN END TO LINGERING SHOWERS DOWN TOWARD THE M-55 CORRIDOR. SOME PESKY LINGERING MID LEVEL MOISTURE WILL LIKELY MILL AROUND DOWN THAT WAY FOR A FEW MORE HOURS WITH BOUTS OF THICKER CLOUD COVER...WHILE AREAS FARTHER NORTH CONTINUE TO SEE LOW/MID LEVEL DRYING WITH THE PASSAGE OF SAID WAVE. THAT SHOULD RESULT IN A GOOD DEAL OF SUNSHINE THROUGH EARLY AFTERNOON...THOUGH WITH THE TYPICAL SUMMERTIME BLOSSOMING OF SOME CUMULUS BENEATH WEAKISH THERMAL TROUGHING STILL IN PLACE. NOT AT ALL CONVINCED WE WILL REALIZE ANY ADDITIONAL SHOWERS LATER THIS AFTERNOON...AS THE BOUNDARY LAYER ALREADY LOOKS A SHADE DRIER THAN YESTERDAY PER 12Z APX RAOB...INDICATIVE OF DEW POINTS LIKELY MIXING OUT BACK THROUGH THE LOWER 50S WHILE AFTERNOON HIGHS REMAIN QUITE SIMILAR TO THOSE OF 24 HOURS AGO. GIVEN LITTLE THERMAL ADVECTION ALOFT THROUGH THE DAY...IT WILL TAKE BETTER MOISTURE POOLING TO JUST SQUEEZE BY THE CAP UP AROUND 600 MB. IF THAT`S GOING TO HAPPEN ANYWHERE IT WILL BE ACROSS THE SOUTHEAST CWA WHERE BETTER LAKE BREEZE CONVERGENCE SHOULD RESIDE OFF LAKE HURON/SAGINAW BAY...BUT EVEN THERE THE CHANCE IS QUITE LOW. HAVE LOWERED POPS INTO THE `ISOLATED` RANGE WHILE ALSO RAISING HIGHS A COUPLE DEGREES FOR MANY AREAS BASED OFF YESTERDAY`S READINGS AND LITTLE CHANGE IN AIRMASS...NOT TO MENTION CURRENT OBS ALREADY WITHIN 5-7 DEGREES OF GOING HIGHS. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...ONE MORE CHANCE FOR SHOWERS AND STORMS... IMPACTS: LIGHTNING THIS AFTERNOON...MAINLY SOUTH OF M-72. CURRENT WEATHER AND SYNOPTIC PATTERN: NO SURPRISE TO THE UPPER LEVEL PATTERN WITH TROUGHING ACROSS THE EASTERN COUNTRY INCLUDING THE GREAT LAKES...AND RIDGING OVER THE WEST. SFC HIGH PRESSURE AND DRIEST AIR WAS DRAPED FROM THE DAKOTAS THROUGH SRN ONTARIO...NOSING INTO EASTERN UPPER. A FRONTAL BOUNDARY WAS NOTED FROM THE EASTERN GREAT LAKES THROUGH SRN LOWER AND INTO WISCONSIN. THERE WAS AN AXIS OF INCREASED H8 MOISTURE AND ELEVATED FRONT STILL HOLDING ACROSS AREAS SOUTH OF M-32...WITH AN INCOMING SHORTWAVE IN NW FLOW ALOFT. THIS HAS RESULTED IN A BAND OF SHOWERS THERE...BUT NO THUNDER THUS FAR. THERE IS JUST A LACK OF INSTABILITY (WHICH REMAINS NEARER THE SFC FRONT IN SRN LOWER). SYNOPTIC PATTERN/WEATHER EVOLUTION: STILL FACING THE SAME PROBLEM WITH THE TODAY/TONIGHT FORECAST. THIS REVOLVES AROUND WHETHER OR NOT WE WILL SEE ANY AFTERNOON AND EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. YESTERDAYS NON-ACTION WAS A LITTLE SURPRISING BUT RESULTED IN A QUICK LOOK BACK AT DATA. THE 00Z APX SOUNDING SHOWED MUCH DRIER AIR BELOW 750MB THAN WHAT WAS SUGGESTED IN YESTERDAYS DATA. MODELS HAVE OVER-FORECASTED BL MOISTURE OVER THE LAST FEW DAYS. LATEST RUC SHOWING A WEDGE OF DRIER H8 AIR SWEEPING DOWN INTO US BEHIND THE SHORTWAVE AND SHOWERS WHICH WILL DEPART BY MID MORNING. THIS WILL BRING A PERIOD OF QUIET NO PRECIP WEATHER. HEATING THROUGH THE DAY WILL ALLOW TEMPS TO MAX OUT HIGHER THAN GUIDANCE (ALSO RUNNING TOO COOL) IN THE MID AND UPPER 70S. FCST BFR SOUNDINGS SHOW INCORRECT INCREASED MOISTURE DEVELOPING AROUND H8 (A FUNCTION OF CONVECTION TAKING OFF IN THE MODELS)...WHAT IS MORE LIKELY IS FOR VERY SHALLOW RIDGING THIS AFTERNOON BEHIND THE WAVE...WITH VERY LITTLE IN THE WAY OF ADVECTION DUE TO CONTINUED LIGHT WINDS. AM EXPECTING THE BL TO MIX OUT DECENTLY AGAIN (BUT CURRENT RAINS WILL ADD TO LOW LEVEL MOISTURE AVAILABILITY). FCST SOUNDINGS SHOW CONTINUED COOLING ALOFT (WHICH SEEMS ODD CONSIDERING THE SHALLOW RIDGING)...AND SFC BASED DEW POINTS (OUTSIDE OF WHERE CURRENT RAIN SHOWERS RESIDE) ARE A COUPLE/FEW DEGREES TOO HIGH. REGARDLESS...EVEN TAKING A FAIRLY DRY PARCEL...MODIFICATION RESULTS IN SNEAKING BY A WEAK CAP ALOFT AROUND 600MB. 400-800 J/KG ARE SEEN IN INTERIOR NRN LOWER (WHERE LAKE BREEZE CONVERGENCE WILL MAXIMIZE). CAN SEE ISOLATED TO SCATTERED SHOWERS AND A FEW STORMS FIRING OFF...WITH NOTHING IN THE LAKE BREEZE CONVERGENCE IN MACKINAC COUNTY DUE TO TOO DRY OF AIR. THESE SHOWERS WILL LIKELY FADE OFF THROUGH EVENING...BUT WILL HAVE TO WATCH NEXT INCOMING SHORTWAVE FROM ONTARIO LATER TONIGHT. THERE MAY BE AN OUTSIDE CHANCE THAT A FEW OF THESE SHOWERS MAY BE ABLE TO CONTINUE INTO THE NIGHT...BUT CONFIDENCE IN THAT IS RATHER LOW. WILL END ALL SHOWERS BY MID/LATE EVENING. && .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...QUIET THROUGH THE WEEKEND... OVERVIEW...THE BASICS OF THE PATTERN ARE GOING TO MOVE WITH THEM ONLY REESTABLISHING THEMSELVES BY NEXT WEEK. SO THE MAIN IDEA WILL BE THAT THE RIDGE IN THE WEST WILL MIGRATE EAST INTO THE UPPER GREAT LAKES. THIS WILL PRODUCE MAINLY DRY WEATHER THROUGH THE WEEKEND. THEN THE CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY. SO WITH THAT IN MIND THE FORECAST LOOKS LIKE THIS... (8/6)WEDNESDAY AND (8/7)THURSDAY...THE SFC HIGH BUILDS OVER THE REGION WEDNESDAY AS A 500 MB SHORTWAVE TROUGH MOVES THROUGH THE REGION WITH FAIRLY DRY AIR (700-500 MB LAYER RH <30% AND 850 MB RH <50%). THIS LEAVES THE REGION RAIN FREE. THE SAME CONDITIONS ARE EXPECTED TO REMAIN OVER THE UPPER GREAT LAKES AS THE RIDGING TAKES PLACE THROUGH THE LOWER AND MID LEVELS. EXTENDED (FRIDAY THROUGH MONDAY)...THE RIDGING IS EXPECTED TO REMAIN FRIDAY AND SATURDAY AS WELL, AT LEAST ON THE ECMWF. THE GFS TRIES TO RAM RAIN NORTH INTO THE SW COUNTIES LATE ON SATURDAY AS SOME SHORTWAVE DIGS INTO THE 500 MB RIDGE. HOWEVER, THINK THAT THE ECMWF IS THE BETTER OF THE TWO MODELS AS THE 500MB RIDGING SHOULD REMAIN STRONG ENOUGH TO SHUNT THE SHORTWAVE NORTH. IT NOT UNTIL (8/10)SUNDAY THAT WE BEGIN TO GET A CHANGE FOR SOMETHING ORGANIZED. WHILE THE DAY AND NIGHT STILL REMAIN DRY, A 500 MB TROUGH AND SFC COLD FRONT BEGINS TO MARCH INTO THE UPPER GREAT LAKES, LATE ON SUNDAY NIGHT. THE MODELS ARE BEGINNING TO PUSH THE FRONT THROUGH ON MONDAY OR MONDAY NIGHT. THE ECMWF IS THE FASTER OF THE TWO MODELS, IN THIS CASE. SO WILL CONTINUE THE MONDAY POPS AND CONTINUE THEM INTO MONDAY NIGHT AS THE BOTH THE ECWMF AND THE GFS HAVE THE FRONT OVER THE FORECAST AREA OVERNIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 110 PM EDT TUE AUG 5 2014 PREDOMINANTLY VFR THROUGH THE PERIOD AS HIGH PRESSURE WORKS TOWARD NORTHERN MICHIGAN. A THICKER PERIOD OF CUMULUS CLOUDS IS EXPECTED AROUND KAPN UP THROUGH ABOUT 19Z...WITH A BRIEF PERIOD OF MVFR CEILINGS POSSIBLE BEFORE THINGS SCATTER OUT WITH TIME. SKIES SHOULD BE CLEAR EVERYWHERE OVERNIGHT WITH PERHAPS A LITTLE SHALLOW GROUND/RIVER VALLEY FOG DEVELOPING IN SPOTS...MOST PRONOUNCED AROUND THE KMBL TERMINAL. CLEAR SKIES ARE THEN EXPECTED TO RETURN FOR WEDNESDAY. WINDS WILL REMAIN UNDER 10 KNOTS THROUGH THE PERIOD. && .MARINE... ISSUED AT 357 AM EDT TUE AUG 5 2014 NO WIND AND WAVE ISSUES TO BE CONCERNED WITH FOR SEVERAL DAYS...LIKELY THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE TAKES CONTROL OF THE WEATHER WEDNESDAY ONWARD...WITH DRY AIR AND AFTERNOON LAKE BREEZES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...LAWRENCE SYNOPSIS...JL SHORT TERM...SMD LONG TERM...JL AVIATION...LAWRENCE MARINE...SMD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1024 AM EDT TUE AUG 5 2014 .SYNOPSIS... ISSUED AT 357 AM EDT TUE AUG 5 2014 ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE IN INTERIOR AREAS OF NORTHERN LOWER MICHIGAN THIS AFTERNOON AND EVENING. HIGH PRESSURE WILL THEN SETTLE IN OVER THE GREAT LAKES REGION WEDNESDAY. THIS HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S EACH DAY WITH LOWS GENERALLY IN THE 50S. && .UPDATE... ISSUED AT 1024 AM EDT TUE AUG 5 2014 A NICE EARLY AUGUST DAY UNFOLDING ACROSS THE AREA...WITH THE PASSAGE OF A SHORTWAVE TROUGH BRINGING AN END TO LINGERING SHOWERS DOWN TOWARD THE M-55 CORRIDOR. SOME PESKY LINGERING MID LEVEL MOISTURE WILL LIKELY MILL AROUND DOWN THAT WAY FOR A FEW MORE HOURS WITH BOUTS OF THICKER CLOUD COVER...WHILE AREAS FARTHER NORTH CONTINUE TO SEE LOW/MID LEVEL DRYING WITH THE PASSAGE OF SAID WAVE. THAT SHOULD RESULT IN A GOOD DEAL OF SUNSHINE THROUGH EARLY AFTERNOON...THOUGH WITH THE TYPICAL SUMMERTIME BLOSSOMING OF SOME CUMULUS BENEATH WEAKISH THERMAL TROUGHING STILL IN PLACE. NOT AT ALL CONVINCED WE WILL REALIZE ANY ADDITIONAL SHOWERS LATER THIS AFTERNOON...AS THE BOUNDARY LAYER ALREADY LOOKS A SHADE DRIER THAN YESTERDAY PER 12Z APX RAOB...INDICATIVE OF DEW POINTS LIKELY MIXING OUT BACK THROUGH THE LOWER 50S WHILE AFTERNOON HIGHS REMAIN QUITE SIMILAR TO THOSE OF 24 HOURS AGO. GIVEN LITTLE THERMAL ADVECTION ALOFT THROUGH THE DAY...IT WILL TAKE BETTER MOISTURE POOLING TO JUST SQUEEZE BY THE CAP UP AROUND 600 MB. IF THAT`S GOING TO HAPPEN ANYWHERE IT WILL BE ACROSS THE SOUTHEAST CWA WHERE BETTER LAKE BREEZE CONVERGENCE SHOULD RESIDE OFF LAKE HURON/SAGINAW BAY...BUT EVEN THERE THE CHANCE IS QUITE LOW. HAVE LOWERED POPS INTO THE `ISOLATED` RANGE WHILE ALSO RAISING HIGHS A COUPLE DEGREES FOR MANY AREAS BASED OFF YESTERDAY`S READINGS AND LITTLE CHANGE IN AIRMASS...NOT TO MENTION CURRENT OBS ALREADY WITHIN 5-7 DEGREES OF GOING HIGHS. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...ONE MORE CHANCE FOR SHOWERS AND STORMS... IMPACTS: LIGHTNING THIS AFTERNOON...MAINLY SOUTH OF M-72. CURRENT WEATHER AND SYNOPTIC PATTERN: NO SURPRISE TO THE UPPER LEVEL PATTERN WITH TROUGHING ACROSS THE EASTERN COUNTRY INCLUDING THE GREAT LAKES...AND RIDGING OVER THE WEST. SFC HIGH PRESSURE AND DRIEST AIR WAS DRAPED FROM THE DAKOTAS THROUGH SRN ONTARIO...NOSING INTO EASTERN UPPER. A FRONTAL BOUNDARY WAS NOTED FROM THE EASTERN GREAT LAKES THROUGH SRN LOWER AND INTO WISCONSIN. THERE WAS AN AXIS OF INCREASED H8 MOISTURE AND ELEVATED FRONT STILL HOLDING ACROSS AREAS SOUTH OF M-32...WITH AN INCOMING SHORTWAVE IN NW FLOW ALOFT. THIS HAS RESULTED IN A BAND OF SHOWERS THERE...BUT NO THUNDER THUS FAR. THERE IS JUST A LACK OF INSTABILITY (WHICH REMAINS NEARER THE SFC FRONT IN SRN LOWER). SYNOPTIC PATTERN/WEATHER EVOLUTION: STILL FACING THE SAME PROBLEM WITH THE TODAY/TONIGHT FORECAST. THIS REVOLVES AROUND WHETHER OR NOT WE WILL SEE ANY AFTERNOON AND EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. YESTERDAYS NON-ACTION WAS A LITTLE SURPRISING BUT RESULTED IN A QUICK LOOK BACK AT DATA. THE 00Z APX SOUNDING SHOWED MUCH DRIER AIR BELOW 750MB THAN WHAT WAS SUGGESTED IN YESTERDAYS DATA. MODELS HAVE OVER-FORECASTED BL MOISTURE OVER THE LAST FEW DAYS. LATEST RUC SHOWING A WEDGE OF DRIER H8 AIR SWEEPING DOWN INTO US BEHIND THE SHORTWAVE AND SHOWERS WHICH WILL DEPART BY MID MORNING. THIS WILL BRING A PERIOD OF QUIET NO PRECIP WEATHER. HEATING THROUGH THE DAY WILL ALLOW TEMPS TO MAX OUT HIGHER THAN GUIDANCE (ALSO RUNNING TOO COOL) IN THE MID AND UPPER 70S. FCST BFR SOUNDINGS SHOW INCORRECT INCREASED MOISTURE DEVELOPING AROUND H8 (A FUNCTION OF CONVECTION TAKING OFF IN THE MODELS)...WHAT IS MORE LIKELY IS FOR VERY SHALLOW RIDGING THIS AFTERNOON BEHIND THE WAVE...WITH VERY LITTLE IN THE WAY OF ADVECTION DUE TO CONTINUED LIGHT WINDS. AM EXPECTING THE BL TO MIX OUT DECENTLY AGAIN (BUT CURRENT RAINS WILL ADD TO LOW LEVEL MOISTURE AVAILABILITY). FCST SOUNDINGS SHOW CONTINUED COOLING ALOFT (WHICH SEEMS ODD CONSIDERING THE SHALLOW RIDGING)...AND SFC BASED DEW POINTS (OUTSIDE OF WHERE CURRENT RAIN SHOWERS RESIDE) ARE A COUPLE/FEW DEGREES TOO HIGH. REGARDLESS...EVEN TAKING A FAIRLY DRY PARCEL...MODIFICATION RESULTS IN SNEAKING BY A WEAK CAP ALOFT AROUND 600MB. 400-800 J/KG ARE SEEN IN INTERIOR NRN LOWER (WHERE LAKE BREEZE CONVERGENCE WILL MAXIMIZE). CAN SEE ISOLATED TO SCATTERED SHOWERS AND A FEW STORMS FIRING OFF...WITH NOTHING IN THE LAKE BREEZE CONVERGENCE IN MACKINAC COUNTY DUE TO TOO DRY OF AIR. THESE SHOWERS WILL LIKELY FADE OFF THROUGH EVENING...BUT WILL HAVE TO WATCH NEXT INCOMING SHORTWAVE FROM ONTARIO LATER TONIGHT. THERE MAY BE AN OUTSIDE CHANCE THAT A FEW OF THESE SHOWERS MAY BE ABLE TO CONTINUE INTO THE NIGHT...BUT CONFIDENCE IN THAT IS RATHER LOW. WILL END ALL SHOWERS BY MID/LATE EVENING. && .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...QUIET THROUGH THE WEEKEND... OVERVIEW...THE BASICS OF THE PATTERN ARE GOING TO MOVE WITH THEM ONLY REESTABLISHING THEMSELVES BY NEXT WEEK. SO THE MAIN IDEA WILL BE THAT THE RIDGE IN THE WEST WILL MIGRATE EAST INTO THE UPPER GREAT LAKES. THIS WILL PRODUCE MAINLY DRY WEATHER THROUGH THE WEEKEND. THEN THE CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY. SO WITH THAT IN MIND THE FORECAST LOOKS LIKE THIS... (8/6)WEDNESDAY AND (8/7)THURSDAY...THE SFC HIGH BUILDS OVER THE REGION WEDNESDAY AS A 500 MB SHORTWAVE TROUGH MOVES THROUGH THE REGION WITH FAIRLY DRY AIR (700-500 MB LAYER RH <30% AND 850 MB RH <50%). THIS LEAVES THE REGION RAIN FREE. THE SAME CONDITIONS ARE EXPECTED TO REMAIN OVER THE UPPER GREAT LAKES AS THE RIDGING TAKES PLACE THROUGH THE LOWER AND MID LEVELS. EXTENDED (FRIDAY THROUGH MONDAY)...THE RIDGING IS EXPECTED TO REMAIN FRIDAY AND SATURDAY AS WELL, AT LEAST ON THE ECMWF. THE GFS TRIES TO RAM RAIN NORTH INTO THE SW COUNTIES LATE ON SATURDAY AS SOME SHORTWAVE DIGS INTO THE 500 MB RIDGE. HOWEVER, THINK THAT THE ECMWF IS THE BETTER OF THE TWO MODELS AS THE 500MB RIDGING SHOULD REMAIN STRONG ENOUGH TO SHUNT THE SHORTWAVE NORTH. IT NOT UNTIL (8/10)SUNDAY THAT WE BEGIN TO GET A CHANGE FOR SOMETHING ORGANIZED. WHILE THE DAY AND NIGHT STILL REMAIN DRY, A 500 MB TROUGH AND SFC COLD FRONT BEGINS TO MARCH INTO THE UPPER GREAT LAKES, LATE ON SUNDAY NIGHT. THE MODELS ARE BEGINNING TO PUSH THE FRONT THROUGH ON MONDAY OR MONDAY NIGHT. THE ECMWF IS THE FASTER OF THE TWO MODELS, IN THIS CASE. SO WILL CONTINUE THE MONDAY POPS AND CONTINUE THEM INTO MONDAY NIGHT AS THE BOTH THE ECWMF AND THE GFS HAVE THE FRONT OVER THE FORECAST AREA OVERNIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 653 AM EDT TUE AUG 5 2014 ...VFR... SCATTERED RAIN SHOWERS ARE EXITING AWAY FROM TVC/MBL ATTM WITH CLEARING SKIES QUICKLY SETTLING IN. ONLY A FEW CUMULUS AROUND THE AIRPORTS WITH LAKE BREEZES YET AGAIN. LIGHT/CALM WINDS TONIGHT WITH MAYBE SOME HIGHER LEVEL CLOUD FOR MAINLY PLN/APN. && .MARINE... ISSUED AT 357 AM EDT TUE AUG 5 2014 NO WIND AND WAVE ISSUES TO BE CONCERNED WITH FOR SEVERAL DAYS...LIKELY THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE TAKES CONTROL OF THE WEATHER WEDNESDAY ONWARD...WITH DRY AIR AND AFTERNOON LAKE BREEZES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ UPDATE...LAWRENCE SYNOPSIS...JL SHORT TERM...SMD LONG TERM...JL AVIATION...SMD MARINE...SMD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
655 AM EDT TUE AUG 5 2014 .SYNOPSIS... ISSUED AT 357 AM EDT TUE AUG 5 2014 ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE IN INTERIOR AREAS OF NORTHERN LOWER MICHIGAN THIS AFTERNOON AND EVENING. HIGH PRESSURE WILL THEN SETTLE IN OVER THE GREAT LAKES REGION WEDNESDAY. THIS HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S EACH DAY WITH LOWS GENERALLY IN THE 50S. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...ONE MORE CHANCE FOR SHOWERS AND STORMS... IMPACTS: LIGHTNING THIS AFTERNOON...MAINLY SOUTH OF M-72. CURRENT WEATHER AND SYNOPTIC PATTERN: NO SURPRISE TO THE UPPER LEVEL PATTERN WITH TROUGHING ACROSS THE EASTERN COUNTRY INCLUDING THE GREAT LAKES...AND RIDGING OVER THE WEST. SFC HIGH PRESSURE AND DRIEST AIR WAS DRAPED FROM THE DAKOTAS THROUGH SRN ONTARIO...NOSING INTO EASTERN UPPER. A FRONTAL BOUNDARY WAS NOTED FROM THE EASTERN GREAT LAKES THROUGH SRN LOWER AND INTO WISCONSIN. THERE WAS AN AXIS OF INCREASED H8 MOISTURE AND ELEVATED FRONT STILL HOLDING ACROSS AREAS SOUTH OF M-32...WITH AN INCOMING SHORTWAVE IN NW FLOW ALOFT. THIS HAS RESULTED IN A BAND OF SHOWERS THERE...BUT NO THUNDER THUS FAR. THERE IS JUST A LACK OF INSTABILITY (WHICH REMAINS NEARER THE SFC FRONT IN SRN LOWER). SYNOPTIC PATTERN/WEATHER EVOLUTION: STILL FACING THE SAME PROBLEM WITH THE TODAY/TONIGHT FORECAST. THIS REVOLVES AROUND WHETHER OR NOT WE WILL SEE ANY AFTERNOON AND EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. YESTERDAYS NON-ACTION WAS A LITTLE SURPRISING BUT RESULTED IN A QUICK LOOK BACK AT DATA. THE 00Z APX SOUNDING SHOWED MUCH DRIER AIR BELOW 750MB THAN WHAT WAS SUGGESTED IN YESTERDAYS DATA. MODELS HAVE OVER-FORECASTED BL MOISTURE OVER THE LAST FEW DAYS. LATEST RUC SHOWING A WEDGE OF DRIER H8 AIR SWEEPING DOWN INTO US BEHIND THE SHORTWAVE AND SHOWERS WHICH WILL DEPART BY MID MORNING. THIS WILL BRING A PERIOD OF QUIET NO PRECIP WEATHER. HEATING THROUGH THE DAY WILL ALLOW TEMPS TO MAX OUT HIGHER THAN GUIDANCE (ALSO RUNNING TOO COOL) IN THE MID AND UPPER 70S. FCST BFR SOUNDINGS SHOW INCORRECT INCREASED MOISTURE DEVELOPING AROUND H8 (A FUNCTION OF CONVECTION TAKING OFF IN THE MODELS)...WHAT IS MORE LIKELY IS FOR VERY SHALLOW RIDGING THIS AFTERNOON BEHIND THE WAVE...WITH VERY LITTLE IN THE WAY OF ADVECTION DUE TO CONTINUED LIGHT WINDS. AM EXPECTING THE BL TO MIX OUT DECENTLY AGAIN (BUT CURRENT RAINS WILL ADD TO LOW LEVEL MOISTURE AVAILABILITY). FCST SOUNDINGS SHOW CONTINUED COOLING ALOFT (WHICH SEEMS ODD CONSIDERING THE SHALLOW RIDGING)...AND SFC BASED DEW POINTS (OUTSIDE OF WHERE CURRENT RAIN SHOWERS RESIDE) ARE A COUPLE/FEW DEGREES TOO HIGH. REGARDLESS...EVEN TAKING A FAIRLY DRY PARCEL...MODIFICATION RESULTS IN SNEAKING BY A WEAK CAP ALOFT AROUND 600MB. 400-800 J/KG ARE SEEN IN INTERIOR NRN LOWER (WHERE LAKE BREEZE CONVERGENCE WILL MAXIMIZE). CAN SEE ISOLATED TO SCATTERED SHOWERS AND A FEW STORMS FIRING OFF...WITH NOTHING IN THE LAKE BREEZE CONVERGENCE IN MACKINAC COUNTY DUE TO TOO DRY OF AIR. THESE SHOWERS WILL LIKELY FADE OFF THROUGH EVENING...BUT WILL HAVE TO WATCH NEXT INCOMING SHORTWAVE FROM ONTARIO LATER TONIGHT. THERE MAY BE AN OUTSIDE CHANCE THAT A FEW OF THESE SHOWERS MAY BE ABLE TO CONTINUE INTO THE NIGHT...BUT CONFIDENCE IN THAT IS RATHER LOW. WILL END ALL SHOWERS BY MID/LATE EVENING. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...QUIET THROUGH THE WEEKEND... OVERVIEW...THE BASICS OF THE PATTERN ARE GOING TO MOVE WITH THEM ONLY REESTABLISHING THEMSELVES BY NEXT WEEK. SO THE MAIN IDEA WILL BE THAT THE RIDGE IN THE WEST WILL MIGRATE EAST INTO THE UPPER GREAT LAKES. THIS WILL PRODUCE MAINLY DRY WEATHER THROUGH THE WEEKEND. THEN THE CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY. SO WITH THAT IN MIND THE FORECAST LOOKS LIKE THIS... (8/6)WEDNESDAY AND (8/7)THURSDAY...THE SFC HIGH BUILDS OVER THE REGION WEDNESDAY AS A 500 MB SHORTWAVE TROUGH MOVES THROUGH THE REGION WITH FAIRLY DRY AIR (700-500 MB LAYER RH <30% AND 850 MB RH <50%). THIS LEAVES THE REGION RAIN FREE. THE SAME CONDITIONS ARE EXPECTED TO REMAIN OVER THE UPPER GREAT LAKES AS THE RIDGING TAKES PLACE THROUGH THE LOWER AND MID LEVELS. EXTENDED (FRIDAY THROUGH MONDAY)...THE RIDGING IS EXPECTED TO REMAIN FRIDAY AND SATURDAY AS WELL, AT LEAST ON THE ECMWF. THE GFS TRIES TO RAM RAIN NORTH INTO THE SW COUNTIES LATE ON SATURDAY AS SOME SHORTWAVE DIGS INTO THE 500 MB RIDGE. HOWEVER, THINK THAT THE ECMWF IS THE BETTER OF THE TWO MODELS AS THE 500MB RIDGING SHOULD REMAIN STRONG ENOUGH TO SHUNT THE SHORTWAVE NORTH. IT NOT UNTIL (8/10)SUNDAY THAT WE BEGIN TO GET A CHANGE FOR SOMETHING ORGANIZED. WHILE THE DAY AND NIGHT STILL REMAIN DRY, A 500 MB TROUGH AND SFC COLD FRONT BEGINS TO MARCH INTO THE UPPER GREAT LAKES, LATE ON SUNDAY NIGHT. THE MODELS ARE BEGINNING TO PUSH THE FRONT THROUGH ON MONDAY OR MONDAY NIGHT. THE ECMWF IS THE FASTER OF THE TWO MODELS, IN THIS CASE. SO WILL CONTINUE THE MONDAY POPS AND CONTINUE THEM INTO MONDAY NIGHT AS THE BOTH THE ECWMF AND THE GFS HAVE THE FRONT OVER THE FORECAST AREA OVERNIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 653 AM EDT TUE AUG 5 2014 ...VFR... SCATTERED RAIN SHOWERS ARE EXITING AWAY FROM TVC/MBL ATTM WITH CLEARING SKIES QUICKLY SETTLING IN. ONLY A FEW CUMULUS AROUND THE AIRPORTS WITH LAKE BREEZES YET AGAIN. LIGHT/CALM WINDS TONIGHT WITH MAYBE SOME HIGHER LEVEL CLOUD FOR MAINLY PLN/APN. && .MARINE... ISSUED AT 357 AM EDT TUE AUG 5 2014 NO WIND AND WAVE ISSUES TO BE CONCERNED WITH FOR SEVERAL DAYS...LIKELY THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE TAKES CONTROL OF THE WEATHER WEDNESDAY ONWARD...WITH DRY AIR AND AFTERNOON LAKE BREEZES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ SYNOPSIS...JL SHORT TERM...SMD LONG TERM...JL AVIATION...SMD MARINE...SMD
AREA FORECAST DISCUSSION...CORRECTED
NWS GAYLORD MI
445 AM EDT TUE AUG 5 2014 .SYNOPSIS... ISSUED AT 357 AM EDT TUE AUG 5 2014 ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE IN INTERIOR AREAS OF NORTHERN LOWER MICHIGAN THIS AFTERNOON AND EVENING. HIGH PRESSURE WILL THEN SETTLE IN OVER THE GREAT LAKES REGION WEDNESDAY. THIS HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S EACH DAY WITH LOWS GENERALLY IN THE 50S. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...ONE MORE CHANCE FOR SHOWERS AND STORMS... IMPACTS: LIGHTNING THIS AFTERNOON...MAINLY SOUTH OF M-72. CURRENT WEATHER AND SYNOPTIC PATTERN: NO SURPRISE TO THE UPPER LEVEL PATTERN WITH TROUGHING ACROSS THE EASTERN COUNTRY INCLUDING THE GREAT LAKES...AND RIDGING OVER THE WEST. SFC HIGH PRESSURE AND DRIEST AIR WAS DRAPED FROM THE DAKOTAS THROUGH SRN ONTARIO...NOSING INTO EASTERN UPPER. A FRONTAL BOUNDARY WAS NOTED FROM THE EASTERN GREAT LAKES THROUGH SRN LOWER AND INTO WISCONSIN. THERE WAS AN AXIS OF INCREASED H8 MOISTURE AND ELEVATED FRONT STILL HOLDING ACROSS AREAS SOUTH OF M-32...WITH AN INCOMING SHORTWAVE IN NW FLOW ALOFT. THIS HAS RESULTED IN A BAND OF SHOWERS THERE...BUT NO THUNDER THUS FAR. THERE IS JUST A LACK OF INSTABILITY (WHICH REMAINS NEARER THE SFC FRONT IN SRN LOWER). SYNOPTIC PATTERN/WEATHER EVOLUTION: STILL FACING THE SAME PROBLEM WITH THE TODAY/TONIGHT FORECAST. THIS REVOLVES AROUND WHETHER OR NOT WE WILL SEE ANY AFTERNOON AND EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. YESTERDAYS NON-ACTION WAS A LITTLE SURPRISING BUT RESULTED IN A QUICK LOOK BACK AT DATA. THE 00Z APX SOUNDING SHOWED MUCH DRIER AIR BELOW 750MB THAN WHAT WAS SUGGESTED IN YESTERDAYS DATA. MODELS HAVE OVER-FORECASTED BL MOISTURE OVER THE LAST FEW DAYS. LATEST RUC SHOWING A WEDGE OF DRIER H8 AIR SWEEPING DOWN INTO US BEHIND THE SHORTWAVE AND SHOWERS WHICH WILL DEPART BY MID MORNING. THIS WILL BRING A PERIOD OF QUIET NO PRECIP WEATHER. HEATING THROUGH THE DAY WILL ALLOW TEMPS TO MAX OUT HIGHER THAN GUIDANCE (ALSO RUNNING TOO COOL) IN THE MID AND UPPER 70S. FCST BFR SOUNDINGS SHOW INCORRECT INCREASED MOISTURE DEVELOPING AROUND H8 (A FUNCTION OF CONVECTION TAKING OFF IN THE MODELS)...WHAT IS MORE LIKELY IS FOR VERY SHALLOW RIDGING THIS AFTERNOON BEHIND THE WAVE...WITH VERY LITTLE IN THE WAY OF ADVECTION DUE TO CONTINUED LIGHT WINDS. AM EXPECTING THE BL TO MIX OUT DECENTLY AGAIN (BUT CURRENT RAINS WILL ADD TO LOW LEVEL MOISTURE AVAILABILITY). FCST SOUNDINGS SHOW CONTINUED COOLING ALOFT (WHICH SEEMS ODD CONSIDERING THE SHALLOW RIDGING)...AND SFC BASED DEW POINTS (OUTSIDE OF WHERE CURRENT RAIN SHOWERS RESIDE) ARE A COUPLE/FEW DEGREES TOO HIGH. REGARDLESS...EVEN TAKING A FAIRLY DRY PARCEL...MODIFICATION RESULTS IN SNEAKING BY A WEAK CAP ALOFT AROUND 600MB. 400-800 J/KG ARE SEEN IN INTERIOR NRN LOWER (WHERE LAKE BREEZE CONVERGENCE WILL MAXIMIZE). CAN SEE ISOLATED TO SCATTERED SHOWERS AND A FEW STORMS FIRING OFF...WITH NOTHING IN THE LAKE BREEZE CONVERGENCE IN MACKINAC COUNTY DUE TO TOO DRY OF AIR. THESE SHOWERS WILL LIKELY FADE OFF THROUGH EVENING...BUT WILL HAVE TO WATCH NEXT INCOMING SHORTWAVE FROM ONTARIO LATER TONIGHT. THERE MAY BE AN OUTSIDE CHANCE THAT A FEW OF THESE SHOWERS MAY BE ABLE TO CONTINUE INTO THE NIGHT...BUT CONFIDENCE IN THAT IS RATHER LOW. WILL END ALL SHOWERS BY MID/LATE EVENING. && .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...QUIET THROUGH THE WEEKEND... OVERVIEW...THE BASICS OF THE PATTERN ARE GOING TO MOVE WITH THEM ONLY REESTABLISHING THEMSELVES BY NEXT WEEK. SO THE MAIN IDEA WILL BE THAT THE RIDGE IN THE WEST WILL MIGRATE EAST INTO THE UPPER GREAT LAKES. THIS WILL PRODUCE MAINLY DRY WEATHER THROUGH THE WEEKEND. THEN THE CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY. SO WITH THAT IN MIND THE FORECAST LOOKS LIKE THIS... (8/6)WEDNESDAY AND (8/7)THURSDAY...THE SFC HIGH BUILDS OVER THE REGION WEDNESDAY AS A 500 MB SHORTWAVE TROUGH MOVES THROUGH THE REGION WITH FAIRLY DRY AIR (700-500 MB LAYER RH <30% AND 850 MB RH <50%). THIS LEAVES THE REGION RAIN FREE. THE SAME CONDITIONS ARE EXPECTED TO REMAIN OVER THE UPPER GREAT LAKES AS THE RIDGING TAKES PLACE THROUGH THE LOWER AND MID LEVELS. EXTENDED (FRIDAY THROUGH MONDAY)...THE RIDGING IS EXPECTED TO REMAIN FRIDAY AND SATURDAY AS WELL, AT LEAST ON THE ECMWF. THE GFS TRIES TO RAM RAIN NORTH INTO THE SW COUNTIES LATE ON SATURDAY AS SOME SHORTWAVE DIGS INTO THE 500 MB RIDGE. HOWEVER, THINK THAT THE ECMWF IS THE BETTER OF THE TWO MODELS AS THE 500MB RIDGING SHOULD REMAIN STRONG ENOUGH TO SHUNT THE SHORTWAVE NORTH. IT NOT UNTIL (8/10)SUNDAY THAT WE BEGIN TO GET A CHANGE FOR SOMETHING ORGANIZED. WHILE THE DAY AND NIGHT STILL REMAIN DRY, A 500 MB TROUGH AND SFC COLD FRONT BEGINS TO MARCH INTO THE UPPER GREAT LAKES, LATE ON SUNDAY NIGHT. THE MODELS ARE BEGINNING TO PUSH THE FRONT THROUGH ON MONDAY OR MONDAY NIGHT. THE ECMWF IS THE FASTER OF THE TWO MODELS, IN THIS CASE. SO WILL CONTINUE THE MONDAY POPS AND CONTINUE THEM INTO MONDAY NIGHT AS THE BOTH THE ECWMF AND THE GFS HAVE THE FRONT OVER THE FORECAST AREA OVERNIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 139 AM EDT TUE AUG 5 2014 SOLID VFR CONDITIONS ARE EXPECTED AT ALL NRN LWR MICHIGAN TAF SITES THRU TUESDAY NIGHT AS HIGH PRESSURE GRADUALLY BUILDS INTO THE AREA. A MOISTURE-STARVED SHORT WAVE WILL SWING THRU AREAS SOUTH OF M-32 OVERNIGHT INTO EARLY TUESDAY...RESULTING IN A FEW SHOWERS AROUND TVC AND MBL AND WILL HANDLE WITH VCSH. LIGHT/VARIABLE WINDS OVERNIGHT INTO EARLY TUESDAY WILL BECOME N/NE AOB 10 KTS. && .MARINE... ISSUED AT 357 AM EDT TUE AUG 5 2014 NO WIND AND WAVE ISSUES TO BE CONCERNED WITH FOR SEVERAL DAYS...LIKELY THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE TAKES CONTROL OF THE WEATHER WEDNESDAY ONWARD...WITH DRY AIR AND AFTERNOON LAKE BREEZES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ SYNOPSIS...JL SHORT TERM...SMD LONG TERM...JL AVIATION...MR MARINE...SMD
AREA FORECAST DISCUSSION
NWS GAYLORD MI
405 AM EDT TUE AUG 5 2014 .SYNOPSIS... ISSUED AT 357 AM EDT TUE AUG 5 2014 ISOLATED SHOWERS AND THUNDERSTORMS ARE AGAIN POSSIBLE IN INTERIOR AREAS OF NORTHERN LOWER MICHIGAN THIS AFTERNOON AND EVENING. HIGH PRESSURE WILL THEN SETTLE IN OVER THE GREAT LAKES REGION WEDNESDAY. THIS HIGH PRESSURE WILL REMAIN IN CONTROL OF THE WEATHER THROUGH THE UPCOMING WEEKEND. TEMPERATURES WILL BE IN THE 70S TO LOWER 80S EACH DAY WITH LOWS GENERALLY IN THE 50S. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...ONE MORE CHANCE FOR SHOWERS AND STORMS... IMPACTS: LIGHTNING THIS AFTERNOON...MAINLY SOUTH OF M-72. CURRENT WEATHER AND SYNOPTIC PATTERN: NO SURPRISE TO THE UPPER LEVEL PATTERN WITH TROUGHING ACROSS THE EASTERN COUNTRY INCLUDING THE GREAT LAKES...AND RIDGING OVER THE WEST. SFC HIGH PRESSURE AND DRIEST AIR WAS DRAPED FROM THE DAKOTAS THROUGH SRN ONTARIO...NOSING INTO EASTERN UPPER. A FRONTAL BOUNDARY WAS NOTED FROM THE EASTERN GREAT LAKES THROUGH SRN LOWER AND INTO WISCONSIN. THERE WAS AN AXIS OF INCREASED H8 MOISTURE AND ELEVATED FRONT STILL HOLDING ACROSS AREAS SOUTH OF M-32...WITH AN INCOMING SHORTWAVE IN NW FLOW ALOFT. THIS HAS RESULTED IN A BAND OF SHOWERS THERE...BUT NO THUNDER THUS FAR. THERE IS JUST A LACK OF INSTABILITY (WHICH REMAINS NEARER THE SFC FRONT IN SRN LOWER). SYNOPTIC PATTERN/WEATHER EVOLUTION: STILL FACING THE SAME PROBLEM WITH THE TODAY/TONIGHT FORECAST. THIS REVOLVES AROUND WHETHER OR NOT WE WILL SEE ANY AFTERNOON AND EVENING SHOWER AND THUNDERSTORM DEVELOPMENT. YESTERDAYS NON-ACTION WAS A LITTLE SURPRISING BUT RESULTED IN A QUICK LOOK BACK AT DATA. THE 00Z APX SOUNDING SHOWED MUCH DRIER AIR BELOW 750MB THAN WHAT WAS SUGGESTED IN YESTERDAYS DATA. MODELS HAVE OVER-FORECASTED BL MOISTURE OVER THE LAST FEW DAYS. LATEST RUC SHOWING A WEDGE OF DRIER H8 AIR SWEEPING DOWN INTO US BEHIND THE SHORTWAVE AND SHOWERS WHICH WILL DEPART BY MID MORNING. THIS WILL BRING A PERIOD OF QUIET NO PRECIP WEATHER. HEATING THROUGH THE DAY WILL ALLOW TEMPS TO MAX OUT HIGHER THAN GUIDANCE (ALSO RUNNING TOO COOL) IN THE MID AND UPPER 70S. FCST BFR SOUNDINGS SHOW INCORRECT INCREASED MOISTURE DEVELOPING AROUND H8 (A FUNCTION OF CONVECTION TAKING OFF IN THE MODELS)...WHAT IS MORE LIKELY IS FOR VERY SHALLOW RIDGING THIS AFTERNOON BEHIND THE WAVE...WITH VERY LITTLE IN THE WAY OF ADVECTION DUE TO CONTINUED LIGHT WINDS. AM EXPECTING THE BL TO MIX OUT DECENTLY AGAIN (BUT CURRENT RAINS WILL ADD TO OW LEVEL MOISTURE AVAILABILITY). FCST SOUNDINGS SHOW CONTINUED COOLING ALOFT (WHICH SEEMS ODD CONSIDERING THE SHALLOW RIDGING)...AND SFC BASED MOISTURE (OUTSIDE OF WHERE CURRENT RAIN SHOWERS RESIDE) IS A COUPLE FEW DEGREES TOO HIGH. ALL OF THIS REGARDLESS...EVEN TAKING A FAIRLY DRY PARCEL...MODIFICATION RESULTS IN SNEAKING BY A WEAK CAP ALOFT AROUND 600MB. 400-800 J/KG ARE SEEN IN INTERIOR NRN LOWER (WHERE LAKE BREEZE CONVERGENCE WILL MAXIMIZE). CAN SEE ISOLATED TO SCATTERED SHOWERS AND A FEW STORMS FIRING OFF...WITH NOTHING IN THE LAKE BREEZE CONVERGENCE IN MACKINAC COUNTY DUE TO TOO DRY OF AIR. THESE SHOWERS WILL LIKELY FADE OFF THROUGH EVENING...BUT WILL HAVE TO WATCH NEXT INCOMING SHORTWAVE FROM ONTARIO LATER TONIGHT. THERE MAY BE AN OUTSIDE CHANCE THAT A FEW OF THESE SHOWERS MAY BE ABLE TO CONTINUE INTO THE NIGHT...BUT CONFIDENCE IN THAT IS RATHER LOW. WILL END ALL SHOWERS BY MID/LATE EVENING. && .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 357 AM EDT TUE AUG 5 2014 ...QUIET THROUGH THE WEEKEND... OVERVIEW...THE BASICS OF THE PATTERN ARE GOING TO MOVE WITH THEM ONLY REESTABLISHING THEMSELVES BY NEXT WEEK. SO THE MAIN IDEA WILL BE THAT THE RIDGE IN THE WEST WILL MIGRATE EAST INTO THE UPPER GREAT LAKES. THIS WILL PRODUCE MAINLY DRY WEATHER THROUGH THE WEEKEND. THEN THE CHANCE OF SHOWERS AND THUNDERSTORMS MONDAY. SO WITH THAT IN MIND THE FORECAST LOOKS LIKE THIS... (8/6)WEDNESDAY AND (8/7)THURSDAY...THE SFC HIGH BUILDS OVER THE REGION WEDNESDAY AS A 500 MB SHORTWAVE TROUGH MOVES THROUGH THE REGION WITH FAIRLY DRY AIR (700-500 MB LAYER RH <30% AND 850 MB RH <50%). THIS LEAVES THE REGION RAIN FREE. THE SAME CONDITIONS ARE EXPECTED TO REMAIN OVER THE UPPER GREAT LAKES AS THE RIDGING TAKES PLACE THROUGH THE LOWER AND MID LEVELS. EXTENDED (FRIDAY THROUGH MONDAY)...THE RIDGING IS EXPECTED TO REMAIN FRIDAY AND SATURDAY AS WELL, AT LEAST ON THE ECMWF. THE GFS TRIES TO RAM RAIN NORTH INTO THE SW COUNTIES LATE ON SATURDAY AS SOME SHORTWAVE DIGS INTO THE 500 MB RIDGE. HOWEVER, THINK THAT THE ECMWF IS THE BETTER OF THE TWO MODELS AS THE 500MB RIDGING SHOULD REMAIN STRONG ENOUGH TO SHUNT THE SHORTWAVE NORTH. IT NOT UNTIL (8/10)SUNDAY THAT WE BEGIN TO GET A CHANGE FOR SOMETHING ORGANIZED. WHILE THE DAY AND NIGHT STILL REMAIN DRY, A 500 MB TROUGH AND SFC COLD FRONT BEGINS TO MARCH INTO THE UPPER GREAT LAKES, LATE ON SUNDAY NIGHT. THE MODELS ARE BEGINNING TO PUSH THE FRONT THROUGH ON MONDAY OR MONDAY NIGHT. THE ECMWF IS THE FASTER OF THE TWO MODELS, IN THIS CASE. SO WILL CONTINUE THE MONDAY POPS AND CONTINUE THEM INTO MONDAY NIGHT AS THE BOTH THE ECWMF AND THE GFS HAVE THE FRONT OVER THE FORECAST AREA OVERNIGHT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 139 AM EDT TUE AUG 5 2014 SOLID VFR CONDITIONS ARE EXPECTED AT ALL NRN LWR MICHIGAN TAF SITES THRU TUESDAY NIGHT AS HIGH PRESSURE GRADUALLY BUILDS INTO THE AREA. A MOISTURE-STARVED SHORT WAVE WILL SWING THRU AREAS SOUTH OF M-32 OVERNIGHT INTO EARLY TUESDAY...RESULTING IN A FEW SHOWERS AROUND TVC AND MBL AND WILL HANDLE WITH VCSH. LIGHT/VARIABLE WINDS OVERNIGHT INTO EARLY TUESDAY WILL BECOME N/NE AOB 10 KTS. && .MARINE... ISSUED AT 357 AM EDT TUE AUG 5 2014 NO WIND AND WAVE ISSUES TO BE CONCERNED WITH FOR SEVERAL DAYS...LIKELY THROUGH THE UPCOMING WEEKEND. HIGH PRESSURE TAKES CONTROL OF THE WEATHER WEDNESDAY ONWARD...WITH DRY AIR AND AFTERNOON LAKE BREEZES. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...NONE. LM...NONE. LS...NONE. && $$ SYNOPSIS...JL SHORT TERM...SMD LONG TERM...JL AVIATION...MR MARINE...SMD
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1200 AM CDT Tue Aug 5 2014 .UPDATE: Issued at 955 PM CDT Mon Aug 4 2014 Scattered thunderstorms that were over northern Missouri earlier this evening have dissipated. Still expect additional development over the next few hours as the RAP shows an increase in 925-850mb moisture convergence though 06Z over central and northeast Missouri and west central Illinois that will shift southeast across the CWA through 12Z. Have mainly slight chances of thunderstorms the rest of the evening, but then have low chance pops again overnight. Rest of the forecast including temperatures still looks good and have made only minor adjustments based on latest observations. Britt && .SHORT TERM: (Through Late Tonight) Issued at 356 PM CDT Mon Aug 4 2014 Weak warm advection has fueled the redevelopment of spotty convection just to the east of a KIRK-KCOU-Eminence line over the past few hours. Consensus of much of the short-range, hi-res guidance is that this activity will work east and likely weaken during the evening, but expect another uptick in PoPs after 06z as subtle veering of weak low level jet focuses somewhat stronger lift in a N-S axis roughly centered near or just west of STL area during the predawn hours. Overnight mins are expected to be a couple of degrees warmer than those of last night, primarily due to clouds. Truett .LONG TERM: (Tuesday through Next Monday) Issued at 356 PM CDT Mon Aug 4 2014 12z runs are forecasting a very subtle flattening of the mid level flow regime over the mid-Mississippi heading into midweek. This will cause a southward shift in the baroclinicity and frontal boundary currently locked to our north, and ultimately result in increasing rainfall chances over much of the CWA. By the end of the week, many parts of the CWA should have received some very welcomed wet weather. This morning`s runs offer fairly similar solutions regarding precip trends into Tuesday night. Thunderstorms that manage to develop overnight tonight should drift south and weaken on Tuesday morning, and I`ve continued low PoPs into tomorrow afternoon for areas along and south of a KCOU-KUIN line as surface boundary will be lingering over this part of the FA, and interacting with the increasingly unstable AMS driven by diurnal heating. Any storms that manage to develop Tuesday afternoon should weaken during the evening. Model consensus remains fairly good agreement with large scale trends heading into Tuesday night, with synoptic scale models all forecasting the intensification of the low level jet over the mid Missouri Valley during the late night hours. The resultant theta-e advection/lift should lead to the development of an MCS over IA that will roll southeast, with the leading edge of this system threatening northern sections of our CWA late Tuesday night. NAM is a bit further north with the QPF of this system than the GFS and the ECMWF, and since the NAM has been a bit too far north with the last few convective complexes, have given a nod to the consensus of the more southern solutions. Guidance specifics become a bit more murky heading into Wednesday and Thursday, but all solutions indicate persistent low level WAA into the area, combined with one or shortwaves/vort maxes drifting across the region. Thunderstorm threat on Wednesday will likely be a combination of the aforementioned MCS over northeast parts of the CWA, along with additional more scattered development occurring further to the south due to the above forcing mechanisms, along with possible outflow interaction and increasingly unstable afternoon airmass. Have continued our highest PoPs for Wednesday night and Thursday, as increased baroclinicity should lead to the best low level forcing during this time frame. Heading into the medium range ridge begins to re-exert its influence, but whats left of the westerly flow will allow weak dynamics to cross the area, interacting with the residualy unstable airmass and baroclinic zone that remains parked over the region. Have maintained earlier forecast trends for now, keeping fairly high PoPs into Thursday night, then slowly backing off to low/slight chance PoPs over the weekend and into early next week. Temperature-wise, fairly typical late summer readings can be expected tomorrow, but the combination of clouds and the southward push of cooler air should mean cooler weather over northeast parts of the CWA on Wednesday, and over the rest of the area by Thursday and Friday. Truett && .AVIATION: (For the 06z TAFs through 06z Tuesday Night) Issued at 1154 PM CDT Mon Aug 4 2014 Specifics for KCOU/KUIN: Scattered SH/TS will affect KCOU/KUIN over the next few hours before moving south and east of the terminals. A cold front will sink southward into the region overnight and tomorrow. Additional thunderstorms are possible at KCOU/KUIN during the afternoon hours depending on where the cold front is located relative to the terminals. Specifics for KSTL/KSUS/KCPS: Scattered SH/TS will reach metro area terminals within the next 1-2 hours. Additional thunderstorms are possible after 18z depending on the position of a slow-moving cold front. Kanofsky && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
1156 PM CDT Mon Aug 4 2014 .SHORT TERM...(This Evening through Tuesday) Issued at 240 PM CDT MON AUG 4 2014 A nice cumulus field is developing with daytime heating and instability this afternoon especially over southern Missouri. There is a very subtle upper level shortwave moving through the area this afternoon. The latest HRRR is indicating isolated to scattered convection to develop by 22z near I-44 and move southward into the early evening hours. Will still carry 20 to 30 percent pops for this general area into the evening hours. Another upper level wave will move across the northern part of the state by early tomorrow morning with some possible convection making its way into central Missouri and the eastern Ozarks tomorrow morning. Will carry a slight mention of pops for tomorrow morning for this general area and a slightly better chance for convection east of Highway 65 Tuesday afternoon. .LONG TERM...(Tuesday Night through Monday) Issued at 240 PM CDT MON AUG 4 2014 The upper level ridge of high pressure which has been in control of our weather pattern will break down somewhat over us and allow multiple shortwaves to ride down a west-northwest flow. A front will meander into the region by Thursday and pretty much stall out over the Missouri Ozarks or nearby through weekend. There will be several rounds of convection and possible MCS activity riding along that front through the area. The first chance for widespread convection will be late Wednesday night into Thursday morning with another rounds developing Thursday night into Friday morning and possibly another round Friday night into Saturday morning. Timing and exact placement is difficult to pinpoint down at this time. The ECMWF is most bullish than the GFS and GEM but all have the same idea. Will mention a slight risk for heavy rainfall and some flash flooding threat for the end of the week with widespread one to three inches likely with isolated higher amounts over the eastern Ozarks and central Missouri areas. Temperatures by the end of the week will be dependent on where the stalled front is positioned and on going convection and cloud cover...but generally cooler temperatures in the lower 80s for the eastern half of the CWA and upper 80s for southeast Kansas and far southwest Missouri for the Thursday through Saturday time frame. The front finally lifts back to the north or washes out by early next week with temperatures moderating back to near normal and slight pops lingering in the afternoon. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday Night) Issued at 1147 PM CDT MON AUG 4 2014 For the KSGF/KJLN/KBBG tafs: VFR conditions are expected. A sfc trough will move slowly south into central/southern MO during the taf period veering winds to the west toward 15z. The trough may trigger some scattered convection once again Tue, but coverage is expected to be sparse, but maybe a little more than the past couple of days. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Griffin LONG TERM...Griffin AVIATION...DSA
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
342 PM CDT TUE AUG 5 2014 .SHORT TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 315 PM CDT TUE AUG 5 2014 MAIN FORECAST CHALLENGE WILL BE PCPN CHANCES/TIMING OVER THE NEXT SEVERAL DAYS. SURFACE LOW PRESSURE IS CURRENTLY LOCATED OVER SOUTHWEST NEBRASKA/NORTHWEST KANSAS WITH A WARM FRONT EXTENDING EASTWARD FROM THE LOW CENTER ACROSS SOUTHERN NEBRASKA. UPPER LEVEL RIDGE AXIS CONTINUES TO FLATTEN AND MOVE OVERHEAD WITH SEVERAL EMBEDDED SHORTWAVE TROUGHS MOVING THROUGH THE FLOW. SOME CONVECTION IS ALREADY ONGOING ACROSS WESTERN/CENTRAL PORTIONS OF NEBRASKA THIS AFTERNOON WITHIN STRONG UPSLOPE FLOW. THESE MAY CONTINUE TO SPREAD EAST INTO OUR FAR NORTHWESTERN COUNTIES LATE THIS AFTERNOON/EARLY THIS EVENING AS BOTH THE HRRR AND RAP HAVE BEEN INDICATING. BETTER FORCING FOR ASCENT WILL ENTER INTO THE REGION LATER TONIGHT AS A PIECE OF SHORTWAVE ENERGY TOPS THE FLATTENING RIDGE. THIS COMBINED WITH STRONG ISENTROPIC UPGLIDE NEAR THE 315K SURFACE AND PW`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
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1232 PM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1041 AM CDT TUE AUG 5 2014 SURE ENOUGH A MID-LVL SHWR HAS BRIEFLY DEVELOPED AND PULSED UP NEAR NORTON KS /NRN/ BUT IT IS ALREADY FADING. HAVE INTRODUCED A 20% POP S AND W OF THE TRI-CITIES FROM NOW THRU EARLY AFTERNOON TO ACCT FOR WHAT COULD BE JUST SOME BRIEF SPRINKLES. BUT AN ISOLATED LIGHTNING STRIKE CAN`T BE RULED OUT. UPDATE ISSUED AT 1023 AM CDT TUE AUG 5 2014 BASED ON WHAT HAPPENED WITH DWPTS YESTERDAY SW OF THE TRI-CITIES AND LOOKING AT THIS MORNING`S DDC SOUNDING...DWPTS WERE LOWERED SEVERAL DEGS THIS AFTERNOON/EVENING. WE WILL UPDATE THE FIRE WX FCST WITH THE LOWER RH LEVELS. UPDATE ISSUED AT 937 AM CDT TUE AUG 5 2014 A COUPLE OF VERY SHORT-TERM UPDATES HAVE BEEN PUBLISHED TO KEEP FCST TEMP/DWPT TRENDS ON TRACK WITH REALITY. ALSO BRUSHED UP CLOUDS THRU 00Z AND POPS WERE SCALED BACK THRU 19Z. WE HAVE NOTED THE HRRR ENSEMBLE AND THE NAM/GFS TRY TO DEVELOP A SHWR OR TSTM THIS MORNING IN THE MCK REGION AND POSSIBLY NORTHEASTWARD. THE FIRST FEW VIS SAT PICS DO SHOW SOME CU AND/OR ACCAS. WE WILL CONT TO MONITOR THIS AND MAY NEED TO AMEND THE FCST AS IT IS CURRENTLY DRY S AND W OF THE TRI-CITIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1232 PM CDT TUE AUG 5 2014 THIS AFTERNOON: VFR WITH BKN CIRROSTRATUS AROUND 20K FT. MID-LEVEL CEILINGS WILL GRADUALLY INCREASE...ESPECIALLY AFTER 21Z WHEN SCT TSTMS DEVELOP TO THE W. SE WINDS WILL OCCASIONALLY GUST TO NEAR 20 KTS. CONFIDENCE: HIGH TONIGHT: VFR WITH A CHANCE OF A VFR OR MVFR TSTM BETWEEN 03Z-09Z. MULTI-LAYERED CLOUD DEBRIS INVADE PRIMARILY ABOVE 10K FT. SE WINDS SUBSIDE TO NEAR 10 KTS. LLWS WILL DEVELOP BY 08Z. CONFIDENCE: MEDIUM WED MORNING: VFR WITH MULTI-LAYERED CEILINGS DEPARTING TO THE E. LLWS ENDS BY 14Z. SE WINDS UNDER 10 KTS. CONFIDENCE: HIGH && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...FAY AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1226 PM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1206 PM CDT TUE AUG 5 2014 A FEW MINOR UPDATES IN THE NEAR TERM...MAINLY TO ACCOUNT FOR CURRENT TD/T/CLOUD TRENDS...BUT OTHERWISE THE FORECAST REMAINS SOLID. STILL ANTICIPATING ADDITIONAL SHOWERS AND STORMS THIS AFTERNOON AND INTO THE EVENING ASSOCIATED WITH AN IMPULSE ROTATING NORTHEAST FROM THE CENTRAL ROCKIES. CURRENTLY FAVORING STORMS THIS AFTERNOON FOCUSING OFF THE HIGHER TERRAIN OF EASTERN WYOMING/COLORADO...WITH THE ACTIVITY MOVING EAST INTO THE CWA EARLY THIS EVENING. OTHER DEVELOPMENT IS POSSIBLE ALONG A WEAK DRY LINE AND/OR NORTH OF THE LIFTING SFC BOUNDARY ACROSS NORTH CENTRAL NEBRASKA. PWATS WILL BE 1.50" OR GREATER OVER MOST LOCATIONS...HEAVY RAINFALL IS POSSIBLE WITHIN STORMS. SOMEWHAT MITIGATING THE SEVERE POTENTIAL WILL BE A RELATIVE MINIMUM IN DEEP SHEAR...BUT SUFFICIENT HEATING WILL INCREASE TROPOSPHERIC INSTABILITY THIS AFTERNOON. IN ADDITION...LOW LEVEL SHEAR WILL BE MAXIMIZED JUST NORTH OF THE LIFTING BOUNDARY...WHICH MAY PROMOTE STORM ROTATION AND A BRIEF HAILER OR DAMAGING DOWNBURST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT TUE AUG 5 2014 TODAY AND TONIGHT...MIDLEVEL FRONTOGENESIS WOULD APPEAR TO SHIFT A BIT FARTHER SOUTH INTO NCNTL NEB TODAY ACCORDING TO THE RAP. NONE OF THE OTHER MODELS SHOW THIS BUT GIVEN THE COLD POOL WHICH FORMED IN THE WAKE OF LAST NIGHTS MCS ACROSS SRN SD...THIS WOULD APPEAR LOGICAL. THUS THE FORECAST TODAY AND TONIGHT CARRIES A HIGHER/LIKELY POP IN THE NORTHEAST ZONES WITH SCATTERED TO ISOLD COVERAGE FARTHER SOUTH WHERE THE ATMOSPHERE WILL REMAIN WARMER AND A BIT MORE CAPPED MOST OF THE DAY. H700 MB TEMPERATURES ARE COOL THROUGHOUT THE FCST AREA AT LESS THAN 14C. THE NAM INDICATES THE DISTURBANCE ACROSS SWRN COLORADO WILL MOVE ACROSS THE CNTL SANDHILLS THIS AFTN AND TONIGHT PRODUCING AN ORGANIZED AREA OF CONVECTION IN ADDITION TO THE CONVECTION WHICH WILL LIKELY CONTINUE ALONG AND NORTH OF THE MID LEVEL FRONTOGENESIS. PRECIPITABLE WATER IN THE GFS...NAM AND SREF INCREASE TO 1.5 INCHES OR HIGHER ACROSS ALL OF THE FCST AREA SUPPORTING SCATTERED OR GREATER STORM COVERAGE. THE RAP KEEPS IT AT 1.25 INCHES SOUTH OF THE STALLED FRONT ACROSS NCNTL NEB WITH THE 1.5 INCHES NORTH OF THE FRONT. THE RAP STILL DEVELOPS CONVECTION ACROSS THE SOUTH TODAY ASSOCIATED WITH A SURGE OF DRY AIR MOVING THROUGH THE PANHANDLE AND NERN COLO. A CHECK ON THE SEVERE WEATHER PARAMETERS SHOWS VERY MODEST SEVERE WEATHER POTENTIAL WITH 30 KTS OF BULK EFFECTIVE SHEAR ACROSS THE NORTHEAST AND AROUND 1500 J/KG OF CAPE. AN ISOLATED STORM WOULD SEEM POSSIBLE BUT NOT MUCH MORE IN THIS ENVIRONMENT. K INDICES RISE TO 40C OR GREATER THIS AFTERNOON AHEAD OF THE DRY SURGE AND ACROSS THE NRN ZONES. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 323 AM CDT TUE AUG 5 2014 THE FIRST IN A SERIES OF SHORTWAVES WILL CROSS THE AREA TUESDAY...WITH A COLD FRONT SETTLING SOUTH ACROSS KANSAS IN ITS WAKE ON WEDNESDAY. THE FRONT WILL REMAIN NEARLY STATIONARY THROUGH THE WEEKEND...WITH A SERIES OF SHORTWAVE DISTURBANCES TO PARADE EAST IN ZONAL FLOW ALOFT. THESE WAVES WILL INTERACT WITH A MOISTURE LATENT ATMOSPHERE TO THE NORTH OF THE FRONTAL ZONE ACROSS NEBRASKA...WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS. THE FLOW ALOFT SHOULD BE STRONG ENOUGH TO PROMOTE SOME STORM ORGANIZATION...AND ONE OR TWO MESOSCALE CONVECTIVE COMPLEXES WILL BE POSSIBLE LATE WEEK INTO THE WEEKEND. PATTERN APPEARS TO SUPPORT THE POTENTIAL FOR SOME MUCH NEEDED RAINFALL ACROSS THE AREA. THE OTHER STORY WILL BE RELATIVELY COOL HIGH TEMPERATURES FOR THIS TIME OF YEAR. THIS SEEMS MOST LIKELY ACROSS NORTHERN NEBRASKA...WHERE HIGHS IN THE MID TO UPPER 70S CAN BE EXPECTED MID WEEK...WARMING TO THE LOW 80S DURING THE WEEKEND. ACROSS THE SOUTHWEST...MOSTLY MID TO UPPER 80S ARE EXPECTED EACH DAY. OVERNIGHT LOWS WILL AVERAGE NEAR NORMAL...IN THE 60S...AS HIGHER RELATIVE HUMIDITY WILL HELP KEEP THE MINIMUM TEMPERATURES MILD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1225 PM CDT TUE AUG 5 2014 VISUAL FLIGHT RULES FOR TERMINALS KLBF AND KVTN THROUGH 21Z. BEYOND 21Z CONVECTION WILL REDEVELOP AS SEVERAL DISTURBANCES MOVE ACROSS MOST LIKELY IMPACTING THE KVTN TERMINAL FIRST...THEN FOCUS SHIFTS SOUTH AND WEST TO BRING A FEW STORMS THROUGH THE KLBF TERMINAL THIS EVENING. THE MODELS ARE IN AGREEMENT WITH DEEPENING BOUNDARY LAYER MOISTURE AGAIN OVERNIGHT THAT SHOULD DROP CEILINGS AND LOWER VISIBILITIES AT BOTH TERMINALS. HOW LOW TO GO IS THE MAIN QUESTION WITH MVFR TO IFR CONDITIONS EXPECTED THROUGH 15Z WEDNESDAY. && .LBF WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...JACOBS SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...KECK
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1206 PM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1206 PM CDT TUE AUG 5 2014 A FEW MINOR UPDATES IN THE NEAR TERM...MAINLY TO ACCOUNT FOR CURRENT TD/T/CLOUD TRENDS...BUT OTHERWISE THE FORECAST REMAINS SOLID. STILL ANTICIPATING ADDITIONAL SHOWERS AND STORMS THIS AFTERNOON AND INTO THE EVENING ASSOCIATED WITH AN IMPULSE ROTATING NORTHEAST FROM THE CENTRAL ROCKIES. CURRENTLY FAVORING STORMS THIS AFTERNOON FOCUSING OFF THE HIGHER TERRAIN OF EASTERN WYOMING/COLORADO...WITH THE ACTIVITY MOVING EAST INTO THE CWA EARLY THIS EVENING. OTHER DEVELOPMENT IS POSSIBLE ALONG A WEAK DRY LINE AND/OR NORTH OF THE LIFTING SFC BOUNDARY ACROSS NORTH CENTRAL NEBRASKA. PWATS WILL BE 1.50" OR GREATER OVER MOST LOCATIONS...HEAVY RAINFALL IS POSSIBLE WITHIN STORMS. SOMEWHAT MITIGATING THE SEVERE POTENTIAL WILL BE A RELATIVE MINIMUM IN DEEP SHEAR...BUT SUFFICIENT HEATING WILL INCREASE TROPOSPHERIC INSTABILITY THIS AFTERNOON. IN ADDITION...LOW LEVEL SHEAR WILL BE MAXIMIZED JUST NORTH OF THE LIFTING BOUNDARY...WHICH MAY PROMOTE STORM ROTATION AND A BRIEF HAILER OR DAMAGING DOWNBURST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT TUE AUG 5 2014 TODAY AND TONIGHT...MIDLEVEL FRONTOGENESIS WOULD APPEAR TO SHIFT A BIT FARTHER SOUTH INTO NCNTL NEB TODAY ACCORDING TO THE RAP. NONE OF THE OTHER MODELS SHOW THIS BUT GIVEN THE COLD POOL WHICH FORMED IN THE WAKE OF LAST NIGHTS MCS ACROSS SRN SD...THIS WOULD APPEAR LOGICAL. THUS THE FORECAST TODAY AND TONIGHT CARRIES A HIGHER/LIKELY POP IN THE NORTHEAST ZONES WITH SCATTERED TO ISOLD COVERAGE FARTHER SOUTH WHERE THE ATMOSPHERE WILL REMAIN WARMER AND A BIT MORE CAPPED MOST OF THE DAY. H700 MB TEMPERATURES ARE COOL THROUGHOUT THE FCST AREA AT LESS THAN 14C. THE NAM INDICATES THE DISTURBANCE ACROSS SWRN COLORADO WILL MOVE ACROSS THE CNTL SANDHILLS THIS AFTN AND TONIGHT PRODUCING AN ORGANIZED AREA OF CONVECTION IN ADDITION TO THE CONVECTION WHICH WILL LIKELY CONTINUE ALONG AND NORTH OF THE MID LEVEL FRONTOGENESIS. PRECIPITABLE WATER IN THE GFS...NAM AND SREF INCREASE TO 1.5 INCHES OR HIGHER ACROSS ALL OF THE FCST AREA SUPPORTING SCATTERED OR GREATER STORM COVERAGE. THE RAP KEEPS IT AT 1.25 INCHES SOUTH OF THE STALLED FRONT ACROSS NCNTL NEB WITH THE 1.5 INCHES NORTH OF THE FRONT. THE RAP STILL DEVELOPS CONVECTION ACROSS THE SOUTH TODAY ASSOCIATED WITH A SURGE OF DRY AIR MOVING THROUGH THE PANHANDLE AND NERN COLO. A CHECK ON THE SEVERE WEATHER PARAMETERS SHOWS VERY MODEST SEVERE WEATHER POTENTIAL WITH 30 KTS OF BULK EFFECTIVE SHEAR ACROSS THE NORTHEAST AND AROUND 1500 J/KG OF CAPE. AN ISOLATED STORM WOULD SEEM POSSIBLE BUT NOT MUCH MORE IN THIS ENVIRONMENT. K INDICES RISE TO 40C OR GREATER THIS AFTERNOON AHEAD OF THE DRY SURGE AND ACROSS THE NRN ZONES. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 323 AM CDT TUE AUG 5 2014 THE FIRST IN A SERIES OF SHORTWAVES WILL CROSS THE AREA TUESDAY...WITH A COLD FRONT SETTLING SOUTH ACROSS KANSAS IN ITS WAKE ON WEDNESDAY. THE FRONT WILL REMAIN NEARLY STATIONARY THROUGH THE WEEKEND...WITH A SERIES OF SHORTWAVE DISTURBANCES TO PARADE EAST IN ZONAL FLOW ALOFT. THESE WAVES WILL INTERACT WITH A MOISTURE LATENT ATMOSPHERE TO THE NORTH OF THE FRONTAL ZONE ACROSS NEBRASKA...WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS. THE FLOW ALOFT SHOULD BE STRONG ENOUGH TO PROMOTE SOME STORM ORGANIZATION...AND ONE OR TWO MESOSCALE CONVECTIVE COMPLEXES WILL BE POSSIBLE LATE WEEK INTO THE WEEKEND. PATTERN APPEARS TO SUPPORT THE POTENTIAL FOR SOME MUCH NEEDED RAINFALL ACROSS THE AREA. THE OTHER STORY WILL BE RELATIVELY COOL HIGH TEMPERATURES FOR THIS TIME OF YEAR. THIS SEEMS MOST LIKELY ACROSS NORTHERN NEBRASKA...WHERE HIGHS IN THE MID TO UPPER 70S CAN BE EXPECTED MID WEEK...WARMING TO THE LOW 80S DURING THE WEEKEND. ACROSS THE SOUTHWEST...MOSTLY MID TO UPPER 80S ARE EXPECTED EACH DAY. OVERNIGHT LOWS WILL AVERAGE NEAR NORMAL...IN THE 60S...AS HIGHER RELATIVE HUMIDITY WILL HELP KEEP THE MINIMUM TEMPERATURES MILD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 629 AM CDT TUE AUG 5 2014 IFR ACROSS NCNTL NEB THIS MORNING SHOULD GRADUALLY LIFT TO VFR 15Z-18Z. THEREAFTER SCATTERED TSTMS ARE EXPECTED TO DEVELOP 21Z ONWARD...GENERALLY FROM WEST TO EAST. THE STORM ACTIVITY COULD BECOME NUMEROUS THIS EVENING AS THE DISTURBANCE CURRENTLY ACROSS SWRN COLO LIFTS INTO THE SANDHILLS. STORM ACTIVITY IS EXPECTED TO BECOME LESS ORGANIZED FROM 06Z ONWARD AND BECOME SCATTERED OR ISOLATED BY 12Z WEDNESDAY. THE MODELS SHOW MVFR/IFR CIGS DEVELOPING FROM 04Z ONWARD ACROSS NRN NEBRASKA AND PERHAPS ACROSS THE SANDHILLS ALSO. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JACOBS SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1155 AM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1155 AM CDT TUE AUG 5 2014 MADE A FEW MINOR CHANGES TO AFTERNOON GRIDS AND PRODUCTS EARLIER. WILL TWEAK THINGS AGAIN BY AROUND 1 PM OR SO. RECENT HRRR MODEL RUNS DEPICT STORMS DEVELOP ACROSS PARTS OF NERN NE THIS AFTERNOON AND EVENING. BASED ON THE PATTERN...ALONG WITH THE EXPECTED AMOUNT OF 0-6 KM SHEAR AND DEGREE OF INSTABILITY...IT APPEARS A FEW STORMS MAY APPROACH SEVERE LIMITS. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 250 AM CDT TUE AUG 5 2014 TIMING AND EXTENT OF VARIOUS CONVECTIVE SYSTEMS REMAINS THE PRIMARY FORECAST CONCERN AND CHALLENGE. UPPER RIDGE AXIS WAS LOCATED OVER THE WESTERN HIGH PLAINS EARLY THIS MORNING WITH ONGOING CONVECTION ALONG THE NORTHERN NEBRASKA BORDER STRETCHING FROM SOUTH CENTRAL SOUTH DAKOTA INTO NORTHEAST NEBRASKA AND WEST CENTRAL IOWA. NEW DEVELOPMENT WAS OCCURRING OVER EAST CENTRAL NEBRASKA AROUND OMAHA SINCE 07Z. MODELS SUGGEST THE SHORT TERM WILL BE PUNCTUATED BY PERIODS OF THUNDERSTORMS WITH THE PRIMARY LOCATION CONFINED TO THE NORTH AND EAST OF THE FORECAST AREA INITIALLY TODAY THROUGH WEDNESDAY. MORE WIDESPREAD CONVECTION IS INDICATED ACROSS THE AREA WEDNESDAY NIGHT AND THURSDAY AS ADDITIONAL SHORT WAVES COME ACROSS THE TOP OF THE RIDGE PUSHING THE STRONGER FLOW A BIT FURTHER SOUTH AND ACROSS THE AREA. HARD TO CALL ON TIMING OF EVENTS SO A BROADBRUSH OF POPS COVER MUCH OF THE PERIOD. TEMPERATURES ALSO LIKELY TO BE IMPACTED BY EXTENT OF PRECIP AND CLOUD COVER SO A BLEND OF GUIDANCE USED. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 250 AM CDT TUE AUG 5 2014 SAME GENERAL PATTERN REMAINS IN PLACE FOR MUCH OF THE EXTENDED PERIOD THROUGH THE WEEKEND BEFORE RIDGE REBUILDS OVER THE WESTERN CONUS AND TROUGH BEGINS TO DEVELOP OVER THE EAST. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1155 AM CDT TUE AUG 5 2014 OUTSIDE OF TSRA ACTIVITY...GENERALLY EXPECT VFR CONDITIONS EXCEPT FOR SOME PATCHY FOG AROUND SUNRISE WEDNESDAY. BEST CHANCES FOR MVFR CEILINGS AND VSBYS WITH TSRA BEFORE 06Z WOULD BE AT KOFK... AND WILL WRITE TAFS THAT WAY. MAY LEAVE OUT MENTION OF TSRA AT KOMA AND KLNK FOR NOW...DUE TO UNCERTAINTY AND POTENTIAL BEING MOSTLY AFTER 06Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1041 AM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1041 AM CDT TUE AUG 5 2014 SURE ENOUGH A MID-LVL SHWR HAS BRIEFLY DEVELOPED AND PULSED UP NEAR NORTON KS /NRN/ BUT IT IS ALREADY FADING. HAVE INTRODUCED A 20% POP S AND W OF THE TRI-CITIES FROM NOW THRU EARLY AFTERNOON TO ACCT FOR WHAT COULD BE JUST SOME BRIEF SPRINKLES. BUT AN ISOLATED LIGHTNING STRIKE CAN`T BE RULED OUT. UPDATE ISSUED AT 1023 AM CDT TUE AUG 5 2014 BASED ON WHAT HAPPENED WITH DWPTS YESTERDAY SW OF THE TRI-CITIES AND LOOKING AT THIS MORNING`S DDC SOUNDING...DWPTS WERE LOWERED SEVERAL DEGS THIS AFTERNOON/EVENING. WE WILL UPDATE THE FIRE WX FCST WITH THE LOWER RH LEVELS. UPDATE ISSUED AT 937 AM CDT TUE AUG 5 2014 A COUPLE OF VERY SHORT-TERM UPDATES HAVE BEEN PUBLISHED TO KEEP FCST TEMP/DWPT TRENDS ON TRACK WITH REALITY. ALSO BRUSHED UP CLOUDS THRU 00Z AND POPS WERE SCALED BACK THRU 19Z. WE HAVE NOTED THE HRRR ENSEMBLE AND THE NAM/GFS TRY TO DEVELOP A SHWR OR TSTM THIS MORNING IN THE MCK REGION AND POSSIBLY NORTHEASTWARD. THE FIRST FEW VIS SAT PICS DO SHOW SOME CU AND/OR ACCAS. WE WILL CONT TO MONITOR THIS AND MAY NEED TO AMEND THE FCST AS IT IS CURRENTLY DRY S AND W OF THE TRI-CITIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 613 AM CDT TUE AUG 5 2014 MVFR VISIBILITY HAS DEVELOPED IN THE AREA. WILL LEAVE IT AT MVFR SINCE LOWER VISIBILITY SHOULD BE TO THE EAST OF THE TERMINAL AREAS. THERE COULD BE A FEW THUNDERSTORMS AROUND THE AREA MAINLY DURING THE EVENING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...FAY AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1023 AM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1023 AM CDT TUE AUG 5 2014 BASED ON WHAT HAPPENED WITH DWPTS YESTERDAY SW OF THE TRI-CITIES AND LOOKING AT THIS MORNING`S DDC SOUNDING...DWPTS WERE LOWERED SEVERAL DEGS THIS AFTERNOON/EVENING. WE WILL UPDATE THE FIRE WX FCST WITH THE LOWER RH LEVELS. UPDATE ISSUED AT 937 AM CDT TUE AUG 5 2014 A COUPLE OF VERY SHORT-TERM UPDATES HAVE BEEN PUBLISHED TO KEEP FCST TEMP/DWPT TRENDS ON TRACK WITH REALITY. ALSO BRUSHED UP CLOUDS THRU 00Z AND POPS WERE SCALED BACK THRU 19Z. WE HAVE NOTED THE HRRR ENSEMBLE AND THE NAM/GFS TRY TO DEVELOP A SHWR OR TSTM THIS MORNING IN THE MCK REGION AND POSSIBLY NORTHEASTWARD. THE FIRST FEW VIS SAT PICS DO SHOW SOME CU AND/OR ACCAS. WE WILL CONT TO MONITOR THIS AND MAY NEED TO AMEND THE FCST AS IT IS CURRENTLY DRY S AND W OF THE TRI-CITIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 613 AM CDT TUE AUG 5 2014 MVFR VISIBILITY HAS DEVELOPED IN THE AREA. WILL LEAVE IT AT MVFR SINCE LOWER VISIBILITY SHOULD BE TO THE EAST OF THE TERMINAL AREAS. THERE COULD BE A FEW THUNDERSTORMS AROUND THE AREA MAINLY DURING THE EVENING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...FAY AVIATION...JCB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
937 AM CDT TUE AUG 5 2014 .UPDATE... ISSUED AT 937 AM CDT TUE AUG 5 2014 A COUPLE OF VERY SHORT-TERM UPDATES HAVE BEEN PUBLISHED TO KEEP FCST TEMP/DWPT TRENDS ON TRACK WITH REALITY. ALSO BRUSHED UP CLOUDS THRU 00Z AND POPS WERE SCALED BACK THRU 19Z. WE HAVE NOTED THE HRRR ENSEMBLE AND THE NAM/GFS TRY TO DEVELOP A SHWR OR TSTM THIS MORNING IN THE MCK REGION AND POSSIBLY NORTHEASTWARD. THE FIRST FEW VIS SAT PICS DO SHOW SOME CU AND/OR ACCAS. WE WILL CONT TO MONITOR THIS AND MAY NEED TO AMEND THE FCST AS IT IS CURRENTLY DRY S AND W OF THE TRI-CITIES. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 613 AM CDT TUE AUG 5 2014 MVFR VISIBILITY HAS DEVELOPED IN THE AREA. WILL LEAVE IT AT MVFR SINCE LOWER VISIBILITY SHOULD BE TO THE EAST OF THE TERMINAL AREAS. THERE COULD BE A FEW THUNDERSTORMS AROUND THE AREA MAINLY DURING THE EVENING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...JCB LONG TERM...FAY AVIATION...JCB
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
636 AM CDT TUE AUG 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT TUE AUG 5 2014 TODAY AND TONIGHT...MIDLEVEL FRONTOGENESIS WOULD APPEAR TO SHIFT A BIT FARTHER SOUTH INTO NCNTL NEB TODAY ACCORDING TO THE RAP. NONE OF THE OTHER MODELS SHOW THIS BUT GIVEN THE COLD POOL WHICH FORMED IN THE WAKE OF LAST NIGHTS MCS ACROSS SRN SD...THIS WOULD APPEAR LOGICAL. THUS THE FORECAST TODAY AND TONIGHT CARRIES A HIGHER/LIKELY POP IN THE NORTHEAST ZONES WITH SCATTERED TO ISOLD COVERAGE FARTHER SOUTH WHERE THE ATMOSPHERE WILL REMAIN WARMER AND A BIT MORE CAPPED MOST OF THE DAY. H700 MB TEMPERATURES ARE COOL THROUGHOUT THE FCST AREA AT LESS THAN 14C. THE NAM INDICATES THE DISTURBANCE ACROSS SWRN COLORADO WILL MOVE ACROSS THE CNTL SANDHILLS THIS AFTN AND TONIGHT PRODUCING AN ORGANIZED AREA OF CONVECTION IN ADDITION TO THE CONVECTION WHICH WILL LIKELY CONTINUE ALONG AND NORTH OF THE MID LEVEL FRONTOGENESIS. PRECIPITABLE WATER IN THE GFS...NAM AND SREF INCREASE TO 1.5 INCHES OR HIGHER ACROSS ALL OF THE FCST AREA SUPPORTING SCATTERED OR GREATER STORM COVERAGE. THE RAP KEEPS IT AT 1.25 INCHES SOUTH OF THE STALLED FRONT ACROSS NCNTL NEB WITH THE 1.5 INCHES NORTH OF THE FRONT. THE RAP STILL DEVELOPS CONVECTION ACROSS THE SOUTH TODAY ASSOCIATED WITH A SURGE OF DRY AIR MOVING THROUGH THE PANHANDLE AND NERN COLO. A CHECK ON THE SEVERE WEATHER PARAMETERS SHOWS VERY MODEST SEVERE WEATHER POTENTIAL WITH 30 KTS OF BULK EFFECTIVE SHEAR ACROSS THE NORTHEAST AND AROUND 1500 J/KG OF CAPE. AN ISOLATED STORM WOULD SEEM POSSIBLE BUT NOT MUCH MORE IN THIS ENVIRONMENT. K INDICES RISE TO 40C OR GREATER THIS AFTERNOON AHEAD OF THE DRY SURGE AND ACROSS THE NRN ZONES. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 323 AM CDT TUE AUG 5 2014 THE FIRST IN A SERIES OF SHORTWAVES WILL CROSS THE AREA TUESDAY...WITH A COLD FRONT SETTLING SOUTH ACROSS KANSAS IN ITS WAKE ON WEDNESDAY. THE FRONT WILL REMAIN NEARLY STATIONARY THROUGH THE WEEKEND...WITH A SERIES OF SHORTWAVE DISTURBANCES TO PARADE EAST IN ZONAL FLOW ALOFT. THESE WAVES WILL INTERACT WITH A MOISTURE LATENT ATMOSPHERE TO THE NORTH OF THE FRONTAL ZONE ACROSS NEBRASKA...WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS. THE FLOW ALOFT SHOULD BE STRONG ENOUGH TO PROMOTE SOME STORM ORGANIZATION...AND ONE OR TWO MESOSCALE CONVECTIVE COMPLEXES WILL BE POSSIBLE LATE WEEK INTO THE WEEKEND. PATTERN APPEARS TO SUPPORT THE POTENTIAL FOR SOME MUCH NEEDED RAINFALL ACROSS THE AREA. THE OTHER STORY WILL BE RELATIVELY COOL HIGH TEMPERATURES FOR THIS TIME OF YEAR. THIS SEEMS MOST LIKELY ACROSS NORTHERN NEBRASKA...WHERE HIGHS IN THE MID TO UPPER 70S CAN BE EXPECTED MID WEEK...WARMING TO THE LOW 80S DURING THE WEEKEND. ACROSS THE SOUTHWEST...MOSTLY MID TO UPPER 80S ARE EXPECTED EACH DAY. OVERNIGHT LOWS WILL AVERAGE NEAR NORMAL...IN THE 60S...AS HIGHER RELATIVE HUMIDITY WILL HELP KEEP THE MINIMUM TEMPERATURES MILD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 629 AM CDT TUE AUG 5 2014 IFR ACROSS NCNTL NEB THIS MORNING SHOULD GRADUALLY LIFT TO VFR 15Z-18Z. THEREAFTER SCATTERED TSTMS ARE EXPECTED TO DEVELOP 21Z ONWARD...GENERALLY FROM WEST TO EAST. THE STORM ACTIVITY COULD BECOME NUMEROUS THIS EVENING AS THE DISTURBANCE CURRENTLY ACROSS SWRN COLO LIFTS INTO THE SANDHILLS. STORM ACTIVITY IS EXPECTED TO BECOME LESS ORGANIZED FROM 06Z ONWARD AND BECOME SCATTERED OR ISOLATED BY 12Z WEDNESDAY. THE MODELS SHOW MVFR/IFR CIGS DEVELOPING FROM 04Z ONWARD ACROSS NRN NEBRASKA AND PERHAPS ACROSS THE SANDHILLS ALSO. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
615 AM CDT TUE AUG 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 613 AM CDT TUE AUG 5 2014 MVFR VISIBILITY HAS DEVELOPED IN THE AREA. WILL LEAVE IT AT MVFR SINCE LOWER VISIBILITY SHOULD BE TO THE EAST OF THE TERMINAL AREAS. THERE COULD BE A FEW THUNDERSTORMS AROUND THE AREA MAINLY DURING THE EVENING HOURS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...FAY AVIATION...JCB
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
342 AM CDT TUE AUG 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT TUE AUG 5 2014 TODAY AND TONIGHT...MIDLEVEL FRONTOGENESIS WOULD APPEAR TO SHIFT A BIT FARTHER SOUTH INTO NCNTL NEB TODAY ACCORDING TO THE RAP. NONE OF THE OTHER MODELS SHOW THIS BUT GIVEN THE COLD POOL WHICH FORMED IN THE WAKE OF LAST NIGHTS MCS ACROSS SRN SD...THIS WOULD APPEAR LOGICAL. THUS THE FORECAST TODAY AND TONIGHT CARRIES A HIGHER/LIKELY POP IN THE NORTHEAST ZONES WITH SCATTERED TO ISOLD COVERAGE FARTHER SOUTH WHERE THE ATMOSPHERE WILL REMAIN WARMER AND A BIT MORE CAPPED MOST OF THE DAY. H700 MB TEMPERATURES ARE COOL THROUGHOUT THE FCST AREA AT LESS THAN 14C. THE NAM INDICATES THE DISTURBANCE ACROSS SWRN COLORADO WILL MOVE ACROSS THE CNTL SANDHILLS THIS AFTN AND TONIGHT PRODUCING AN ORGANIZED AREA OF CONVECTION IN ADDITION TO THE CONVECTION WHICH WILL LIKELY CONTINUE ALONG AND NORTH OF THE MID LEVEL FRONTOGENESIS. PRECIPITABLE WATER IN THE GFS...NAM AND SREF INCREASE TO 1.5 INCHES OR HIGHER ACROSS ALL OF THE FCST AREA SUPPORTING SCATTERED OR GREATER STORM COVERAGE. THE RAP KEEPS IT AT 1.25 INCHES SOUTH OF THE STALLED FRONT ACROSS NCNTL NEB WITH THE 1.5 INCHES NORTH OF THE FRONT. THE RAP STILL DEVELOPS CONVECTION ACROSS THE SOUTH TODAY ASSOCIATED WITH A SURGE OF DRY AIR MOVING THROUGH THE PANHANDLE AND NERN COLO. A CHECK ON THE SEVERE WEATHER PARAMETERS SHOWS VERY MODEST SEVERE WEATHER POTENTIAL WITH 30 KTS OF BULK EFFECTIVE SHEAR ACROSS THE NORTHEAST AND AROUND 1500 J/KG OF CAPE. AN ISOLATED STORM WOULD SEEM POSSIBLE BUT NOT MUCH MORE IN THIS ENVIRONMENT. K INDICES RISE TO 40C OR GREATER THIS AFTERNOON AHEAD OF THE DRY SURGE AND ACROSS THE NRN ZONES. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 323 AM CDT TUE AUG 5 2014 THE FIRST IN A SERIES OF SHORTWAVES WILL CROSS THE AREA TUESDAY...WITH A COLD FRONT SETTLING SOUTH ACROSS KANSAS IN ITS WAKE ON WEDNESDAY. THE FRONT WILL REMAIN NEARLY STATIONARY THROUGH THE WEEKEND...WITH A SERIES OF SHORTWAVE DISTURBANCES TO PARADE EAST IN ZONAL FLOW ALOFT. THESE WAVES WILL INTERACT WITH A MOISTURE LATENT ATMOSPHERE TO THE NORTH OF THE FRONTAL ZONE ACROSS NEBRASKA...WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS. THE FLOW ALOFT SHOULD BE STRONG ENOUGH TO PROMOTE SOME STORM ORGANIZATION...AND ONE OR TWO MESOSCALE CONVECTIVE COMPLEXES WILL BE POSSIBLE LATE WEEK INTO THE WEEKEND. PATTERN APPEARS TO SUPPORT THE POTENTIAL FOR SOME MUCH NEEDED RAINFALL ACROSS THE AREA. THE OTHER STORY WILL BE RELATIVELY COOL HIGH TEMPERATURES FOR THIS TIME OF YEAR. THIS SEEMS MOST LIKELY ACROSS NORTHERN NEBRASKA...WHERE HIGHS IN THE MID TO UPPER 70S CAN BE EXPECTED MID WEEK...WARMING TO THE LOW 80S DURING THE WEEKEND. ACROSS THE SOUTHWEST...MOSTLY MID TO UPPER 80S ARE EXPECTED EACH DAY. OVERNIGHT LOWS WILL AVERAGE NEAR NORMAL...IN THE 60S...AS HIGHER RELATIVE HUMIDITY WILL HELP KEEP THE MINIMUM TEMPERATURES MILD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1240 AM CDT TUE AUG 5 2014 CURRENT RADAR SHOWS A THUNDERSTORM SYSTEM ALONG THE NEBRASKA-SOUTH DAKOTA EAST OF IEN. THE STORMS COULD REACH VTN AS EARLY AS 07Z AND AS LATE AS 09Z. THE STORMS ARE LIKELY TO CONTINUE...AT LEAST INTERMITTENTLY FOR TWO HOURS. PROJECTING THE CURRENT MOVEMENT BRINGS THE STORMS TO VTN ABOUT 08Z. DUE TO THE UNCERTAINTY...WE WILL KEEP THEM IN THE TERMINAL FORECAST WITH A TEMPO GROUP FOR TWO HOURS. ADJUSTMENTS MAY BE NEEDED AS THE SITUATION EVOLVES. AFTER THE THUNDERSTORMS PASS...OCCASIONAL LIGHT SHOWERS WILL PROBABLY CONTINUE FOR AN ADDITIONAL 2 TO 4 HOURS. CURRENT INDICATIONS ARE THAT THE SHOWERS AND THUNDERSTORMS WILL REMAIN NORTH AND WEST OF AN ONL-TIF-AIA LINE. IN THE WAKE OF THE SHOWERS...A EAST WIND WILL CREATE AN UPSLOPE TRAJECTORY OF THE MOISTURE. AS A RESULT...LOW STRATUS CEILINGS ARE LIKELY. THERE IS SOME QUESTION IF THEY WILL BE ABOVE OR BELOW 1000 FEET AGL. FOR VTN...WE WILL HOLD THE CEILING TO JUST ABOVE 1000 FEET UNLESS THERE IS A CLEAR SIGNAL THAT IT WILL BE LESS THAN 1000 FEET AGL. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...TAYLOR AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
328 AM CDT TUE AUG 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 325 AM CDT TUE AUG 5 2014 REGIONAL RADAR SHOWS SOME THUNDERSTORMS ACROSS SOUTHERN SOUTH DAKOTA AND NORTHERN NEBRASKA. THESE HAVE BEEN MOVING EAST OR SOUTHEAST. SURFACE OBSERVATIONS SHOW THAT SOME LIGHT FOG HAS FORMED IN SPOTS BUT SO FAR THE VISIBILITIES HAVE ONLY BEEN 3 TO 5 MILES. THE FIRST CONCERNS WILL BE WHETHER THE THUNDERSTORMS TO THE NORTH WILL GET INTO THE AREA THIS MORNING AND IF THE FOG WILL HAVE AN IMPACT ON VISIBILITY BY MORNING. WITH THE CURRENT MOVEMENT EXPECT THAT THE MAJORITY OF THE THUNDERSTORMS WILL REMAIN NORTH OF THE AREA BUT HAVE KEPT SOME LOW POPS IN THE FAR NORTH OR NORTHEAST. SO FAR THE VISIBILITY HAS BEEN ABOVE 3 MILES. WINDS ARE A LITTLE STRONGER THAN THEY WERE LAST NIGHT. THE LATEST HRRR CONTINUES TO SHOW LOWER VISIBILITY IN THE FAR NORTHEAST. WILL KEEP SOME PATCHY FOG IN FOR EARLY THIS MORNING. AN UPPER LEVEL WAVE APPROACHES THE AREA THIS AFTERNOON. A SURFACE LOW DEVELOPING ON THE HIGH PLAINS WILL MOVE INTO THE AREA DURING THE DAY. AS THE UPPER LEVEL WAVE MOVES INTO THE AREA...THUNDERSTORMS ARE EXPECTED TO FORM NEAR THE SURFACE LOW AND A SURFACE BOUNDARY EXTENDING TO THE EAST AHEAD OF THE SURFACE LOW. EXPECT A FEW OF THE STORMS COULD BE STRONG THIS AFTERNOON AND EVENING WITH GUSTY WINDS AND SOME SMALL HAIL. THE THUNDERSTORMS ARE EXPECTED TO CONTINUE ACROSS THE AREA TONIGHT AS THE UPPER WAVE MOVES THROUGH THE AREA AND THE SURFACE LOW MOVES INTO THE FORECAST AREA. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 325 AM CDT TUE AUG 5 2014 THE WEATHER PATTERN BECOMES MORE UNSETTLED DURING THE EXTENDED PERIODS. BEGINNING ON WEDNESDAY...CONVECTION MAY BE ONGOING FOR THE FIRST PART OF THE DAY AHEAD OF AN ADVANCING COLD FRONTAL BOUNDARY AS AN UPPER LOW PRESSURES SYSTEM TRANSLATES SOUTHEAST FROM THE DAKOTAS. ALSO A 40KT LOWLEVEL JET ORIENTED TOWARDS THE MO RIVER MAY SUSTAIN THE CONVECTION FOR SEVERAL HOURS IN THE MORNING. THIS INITIAL ROUND OF CONVECTION SHOULD DIMINISH WEDNESDAY MORNING WITH REDEVELOPMENT POSSIBLE DURING THE DAY ALONG THE ADVANCING COLD FRONT AND AS THE UPPER WAVE CONTINUES TO TRANSLATE SOUTHEASTWARD. A STRONG TO SEVERE STORM IS POSSIBLE WITH SREF INSTABILITY PROGS AROUND 2500 J/KG AND SHEAR NEAR 30KTS WHICH COULD LEAD TO A FEW STORMS CAPABLE OF PRODUCING LARGE HAIL/DAMAGING WINDS. PRECIPITABLE WATER VALUES ARE ON THE ORDER OF AN INCH AND A HALF AND IF STORMS CAN GO...DECENT RAINFALL AMOUNTS ARE POSSIBLE. THERE ARE SOME MODEL DIFFERENCES ON HOW QUICKLY THE BOUNDARY WILL MOVE THROUGH WEDNESDAY NIGHT WITH THE NAM FASTER THAN THE GFS WITH THE PROGRESSION. AS THE BOUNDARY MOVES THROUGH...PCPN CHANCES DECREASE N/S WITH COOLER AND DRIER AIR ADVECTING IN AS THE SURFACE RIDGE BUILDS SOUTH BEHIND THE BOUNDARY. THE MODEL DIFFERENCES CARRY INTO THURSDAY WITH THERMAL PROGS/TEMP PROFILES ON THE MODELS WITH THE NAM A FEW DEGREES COOLER WITH MID LEVEL TEMPS THAN THE GFS WHILE THE ECMWF IS IN BETWEEN THE TWO. HAVE WENT WITH MORE OF A MODEL BLEND FOR FORECAST HIGHS WITH THE THERMAL GRADIENT ORIENTED NE/SW. AFTER A MAINLY DRY DAY ON THURSDAY...CONVECTION IS EXPECTED TO REDEVELOP THURSDAY NIGHT TO OUR WEST ALONG THE HIGH PLAINS REGION IN UPSLOPE FLOW. THE GFS IS MORE ROBUST WITH THE CONVECTION WORKING EAST SOUTHEASTWARD THURSDAY NIGHT/EARLY FRIDAY THAN OTHER MODELS. DURING THIS TIME FRAME...THE GFS IS ALSO FARTHER NORTH WITH THE WARM FRONTAL BOUNDARY ACROSS KS WHEREAS NAM SUGGESTS THE BOUNDARY WILL BE IN OKLAHOMA. GIVEN THE UNCERTAINTY HAVE WENT WITH INCREASING CLOUD COVER AND KEPT THE BETTER PCPN CHCS IN OUR SW ZONES. FOR THE REMAINDER OF THE WORKWEEK AND INTO THE WEEKEND...THE PATTERN REMAINS UNSETTLED AS A SERIES OF WAVES CROSS THE INTERIOR CONUS AND THE UPPER RIDGE DAMPENS ACROSS THE SOUTHERN PLAINS. THE RIDGE BEGINS TO REBUILD TO THE NORTH AND WEST OVER THE ROCKIES LATE IN THE WEEKEND WITH A MORE AMPLIFIED NORTHWEST FLOW REGIME RETURNING BY DAY 7. CONVECTIVE POTENTIAL WILL BE DEPENDENT UPON TIMING OF WAVES AND FRONTAL BOUNDARY PLACEMENT WHICH WILL BE REFINED WITH TIME BUT THIS BEING SAID...THE WEATHER PATTERN DOES LOOK MORE ACTIVE DURING THE EXTENDED PERIODS WITH MORE PROMISING POTENTIAL FOR RAINFALL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1208 AM CDT TUE AUG 5 2014 EXPECT THERE COULD BE SOME FOG AGAIN IN THE MORNING. THE LATEST HRRR MODEL HAS SOME SPOTTY VISIBILITY RESTRICTIONS JUST BEFORE SUNRISE THIS MORNING. WILL KEEP THE MVFR VISIBILITY GOING AND KEEP AND EYE ON WHETHER THE VISIBILITY DROPS LOWER. THE WORST SHOULD BE FURTHER TO THE EAST AND KEAR WILL LIKELY HAVE LESS VISIBILITY RESTRICTION. THERE IS A CHANCE FOR SOME THUNDERSTORMS DURING THE EVENING...BUT IT IS SMALL AND WILL KEEP THEM OUT OF THE TAF FOR NOW. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...JCB LONG TERM...FAY AVIATION...JCB
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
255 PM MDT TUE AUG 5 2014 .SYNOPSIS... SHOWERS AND THUNDERSTORMS WILL FAVOR EASTERN NEW MEXICO THROUGH THE EVENING HOURS. A FEW STORMS MAY PRODUCE GUSTY WINDS AND HAIL. ON WEDNESDAY...STORM COVERAGE WILL DECREASE SIGNIFICANTLY AS DRY AIR CONTINUES TO MOVE INTO THE STATE. IF STORMS DEVELOP...THEY WILL FAVOR THE SOUTHWEST AND SOUTH CENTRAL MOUNTAINS. MEANWHILE... TEMPERATURES WILL CLIMB NEAR OR ABOVE SEASONAL NORMALS. MOISTURE WILL SLOWLY START TO MOVE FROM SOUTH TO NORTH...BACK INTO THE LAND OF ENCHANTMENT...THURSDAY THROUGH THE WEEKEND. STORM COVERAGE WILL SLOWLY START TO INCREASE...AND THE POTENTIAL FOR HEAVY RAIN WILL RETURN. HOWEVER...OVERALL COVERAGE IS EXPECTED TO BE LESS THAN RECENT WEEKS. && .DISCUSSION... MUCH DRIER MID AND UPPER LEVEL AIR MOVING INTO NM PER WV SATELLITE IMAGERY AND 12Z FGZ SOUNDING. AS SUCH...CONVECTION HAS REALLY STRUGGLED TO START...OR MAINTAIN ITSELF WEST OF THE CENTRAL MTN CHAIN. MID LEVEL MOISTURE GRADIENT LIKELY SETTING UP ALONG THE CENTRAL MT CHAIN...AND THIS COMBINED WITH OROGRAPHIC LIFT HAS PRODUCED A FEW SHOWERS AND TSTMS. WITH THE AID OF A WEAK 700 MB TROUGH ACROSS NORTHERN NM...AND DRY AIR PUNCHING INTO MID LEVELS...HAVE ALREADY SEEN ONE SEVERE STORM ACROSS THE NE...AND A FEW MORE STRONG OR SEVERE STORMS ARE NOT OUT OF THE QUESTION. QUARTER SIZE HAIL AND GUSTY WINDS WOULD BE THE MAIN THREATS. THE GOOD NEWS IS THAT WITH STORM MOTIONS AVERAGING 10 TO 20 MPH...THE THREAT FOR FLOODING HAS CONSIDERABLY DECREASED...THOUGH ALSO NOT OUT OF THE QUESTION. LATEST AVAILABLE HRRR SUGGESTS THAT MUCH OF THE CONVECTION TONIGHT WILL DIMINISH BY SUNSET. DRY AIR CONTINUING TO FILTER IN COMBINED WITH THE UPPER LEVEL HIGH BUILDING BACK TO THE NORTH WILL RESULT IN AN EVEN BIGGER DOWN TICK IN STORM COVERAGE ON WEDNESDAY. PWATS LOOK TO CRATER TO AROUND 0.50 INCHES...SIMILAR TO WHAT WAS OBSERVED ON THE FGZ SOUNDING THIS AM. TEMPERATURES WILL CLIMB SEVERAL DEGREES...WITH ALL AREAS SEEING NEAR TO ABOVE NORMAL TEMPS FOR THE FIRST TIME IN A WHILE. MODELS SUGGEST THE UPPER HIGH WILL INCH EASTWARD ON THURSDAY...AS SOME DISTURBANCE...LIKELY FROM THE PREVIOUS DAYS CONVECTION OVER MEXICO...WILL MOVE NORTHWARD INTO SOUTHERN NM. PWATS WILL CREEP UP ON THURSDAY...BUT WILL REMAIN BELOW NORMAL FOR THIS TIME OF YEAR. NONETHELESS... A FEW MORE STORMS WILL BE POSSIBLE AT LEAST ACROSS THE SOUTHERN TIER OF THE CWA ON THURSDAY. ADDITIONALLY...THE NAM IS SUGGESTING AREAS ALONG AND JUST EAST OF THE CENTRAL MT CHAIN WILL BE A FAVORED AREA FOR STORM DEVELOPMENT. CONTINUED TO CARRY HIGHER POPS HERE...BUT NOT OVERLY SOLD YET. NEAR AND BEHIND A BACK DOOR FRONT WITH AMPLE LOW LEVEL MOISTURE BEHIND IT ACROSS THE FAR NE MAY BE A BETTER BET FOR STORMS. LOOKING FOR A BIT MORE MOISTURE ON FRIDAY AS THE UPPER HIGH SHIFTS OVER OKLAHOMA...THOUGH MODELS ARE NOT VERY AMBITIOUS AT BRING THE MOISTURE NORTHWARD DESPITE THE FAVORABLE PATTERN. THIS MAY CHANGE IN THE COMING DAYS. THE WEEKEND DOES NOT LOOK TOO MUCH DIFFERENT FROM FRIDAY...OTHER THAN THERE MAY BE A BIT MORE MOISTURE AND STORMS AROUND. PWAT VALUES ARE PROGGED TO BE RIGHT AROUND NORMAL FOR AUGUST. LOOKS LIKE EARLY NEXT WEEK THE UPPER HIGH WILL SHIFT BACK OVER NM...DIVERTING THE MOISTURE PLUME WESTWARD OVER ARIZONA. 34 && .FIRE WEATHER... NO MAJOR CHANGES TO THE GRIDDED FORECAST. DID LOWER DEWPOINT VALUES THUS RH ACROSS MOST OF THE FORECAST AREA DURING THE NEXT FEW DAYS. DESPITE THE DYNAMIC DRY SLOT/MID LEVEL DRY INTRUSION PATTERN...VEGETATION WILL BE GOING OVERTIME IN TERMS OF TRANSPIRATION AT NIGHT SO RAISED OVERNIGHT DEWPOINT VALUES SOME ACROSS THE EAST. MOIST SOILS WILL ALSO KEEP DEWPOINT READINGS FROM FALLING TOO FAR BELOW MODEL GUIDANCE. WENT WITH MORE OF A MODEL BLEND. EITHER WAY...HUMIDITY VALUES FALL BELOW SEASONABLE LEVELS WED/THUR PRETTY MUCH AREAWIDE. THEN MORE SEASONABLE READINGS EXCEPT FOR THE FOUR CORNERS BY FRIDAY AND LASTING INTO THE WEEKEND. LOOKING AT SOME SINGLE DIGIT RH READINGS FOR THE FOUR CORNERS DURING THE UPCOMING FEW DAYS SO PAY MORE ATTENTION TO FIRE STARTS UP THAT BECAUSE OF THE DRIER CONDITIONS. AS FAR AS WETTING RAIN...OVERALL COVERAGE WILL DECREASE PRETTY SIGNIFICANTLY COMPARED TO THE PAST WEEK. A FEW WETTING STORMS FAVORING THE EASTERN THIRD TO HALF WILL OCCUR REST OF TODAY BUT PRETTY ISOLATED. THE DRIER AIR ALOFT WILL KEEP CELLS PRETTY LIMITED WEDNESDAY. A BAGGY TROUGH OR WEAKNESS TO THE WEST OF THE STATE WILL EVENTUALLY DRAW SOME MOISTURE NORTHWARD FROM MEXICO AS THE WEEK PROGRESSES. THIS LOOKS TO BE A SLOW TRANSITION IN TERMS OF WETTING RAIN COVERAGE BUT THE TRANSITION WILL OCCUR BASED ON MODEL COMPARISONS THE PAST DAY OR SO AND TAKING INTO ACCOUNT THE TIME OF YEAR. THE UPPER RIDGE TODAY WILL HAVE SAGGED SOUTHWARD OVER NORTHERN MEXICO BUT AS THE WEEK PROGRESSES LOOK FOR IT TO TRY TO STRENGTHEN NORTHWARD AND EVENTUALLY GET SHUNTED EASTWARD DUE TO THE WESTERN TROUGH. THE NECESSARY DRIVERS OR INGREDIENTS WOULD BE IN PLACE TO DRAW MONSOONAL MOISTURE NORTHWARD FROM MEXICO. THE MAIN QUESTION IS HOW QUICKLY. TEMPERATURES DURING THIS PERIOD WOULD EVENTUALLY WARM SOME BUT HIGHS WOULD GENERALLY BE NEAR TO SLIGHTLY BELOW NORMAL WEST AND NEAR TO SLIGHTLY ABOVE NORMAL EAST. OVERALL WIND SPEEDS LOOK TO BE ON THE LIGHTER SIDE DUE TO THE LACK OF ANY SURFACE OR UPPER LEVEL DRIVERS. THE STRONGEST WIND FOR THE FORECAST AREA LOOKS TO BE TODAY AND FAVOR THE EAST. ANY THUNDER CELLS THAT DO DEVELOP COULD CONTAIN STRONG OUTFLOW WINDS DUE TO THE MID LEVEL/SFC DRYING. LOOKING AT A RETURN TO SOME HAINES 5/6 VALUES DURING THE NEXT FEW DAYS. HAINES 6 MOST LIKELY ACROSS THE FOUR CORNERS THURSDAY. VENTILATION LOOKS TO BE PRETTY DECENT MOST AREAS THROUGH THE END OF THE WEEK BUT LOWER SOME DURING THE WEEKEND. GFS/ECMWF SHOWS SOME CONTINUED ATMOSPHERIC MOISTENING DURING THE WEEKEND INTO EARLY NEXT WEEK AS THE MEAN HIGH PRESSURE CELL PLACEMENT WOULD BE TO THE EAST OF THE STATE. STILL LOOKING AT A BAGGY TROUGH TO THE WEST. THUS...THE MONSOONAL MOISTURE PLUME SHOULD EVENTUALLY CONCENTRATE ITSELF OVER PORTIONS OF AZ/NM. HOW MUCH AND EXACT PLACEMENT IS STILL A LITTLE TRICKY. ANOTHER FLY IN THE OINTMENT WOULD BE AN EASTERLY WAVE COMING OFF THE GULF OF MEXICO. IT IS MOST PROBABLE THAT THIS EASTERLY WAVE WOULD DRAG DRIER MID LEVEL AIR OVER PORTIONS OF THE FORECAST AREA VERSUS PROVIDING A MOISTENING TREND BUT HAVE TO WAIT AND SEE. A PRETTY TYPICAL PERIOD FOR THE WET PHASE OF THE MONSOON SUMMER PERIOD SO NOTHING REAL UNUSUAL UPCOMING. 50 && .AVIATION... 18Z TAF CYCLE MUCH DRIER AIR HAS MOVED OVER THE FORECAST AREA THIS MORNING. THIS WILL LIMIT SH/TS DEVELOPMENT AS WELL AS IMPACTS TO AIRPORTS. USING VCSH OR TEMPO SH FOR SOME OF THE LOCATIONS THAT ARE MORE LIKELY TO BE IMPACTED. FAIRLY DYNAMIC DAY SO LOOK FOR SOME UPDATES ACCORDINGLY. OUTFLOW WIND WOULD PROBABLY BE THE MAIN IMPACT SO USING GUSTS TO 30-35 KT BUT CANT RULE OUT STRONGER. SOME OF THE WETTER STORMS WITH LOWER CIGS/VIS FOR A BRIEF PERIOD EAST OF THE CNTRL MTNS. ACTIVITY SHOULD DWINDLE SOON AFTER SUNSET. 50 && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 59 90 56 92 / 5 5 5 0 DULCE........................... 53 86 45 85 / 10 5 5 10 CUBA............................ 53 85 51 84 / 5 5 5 10 GALLUP.......................... 49 86 46 86 / 5 5 5 5 EL MORRO........................ 48 83 44 80 / 5 10 5 10 GRANTS.......................... 52 86 48 84 / 5 5 5 10 QUEMADO......................... 50 83 50 80 / 10 10 10 10 GLENWOOD........................ 53 89 58 88 / 10 10 10 10 CHAMA........................... 44 79 43 80 / 20 5 5 20 LOS ALAMOS...................... 54 85 54 82 / 20 5 5 20 PECOS........................... 52 84 54 80 / 10 5 5 30 CERRO/QUESTA.................... 50 81 48 80 / 20 5 5 20 RED RIVER....................... 43 74 44 73 / 20 10 10 30 ANGEL FIRE...................... 42 78 42 78 / 20 5 5 30 TAOS............................ 50 84 48 85 / 20 5 5 10 MORA............................ 52 84 52 81 / 20 5 5 30 ESPANOLA........................ 58 89 58 87 / 10 0 5 10 SANTA FE........................ 54 84 57 84 / 10 5 5 20 SANTA FE AIRPORT................ 55 88 57 88 / 5 5 5 20 ALBUQUERQUE FOOTHILLS........... 60 89 62 88 / 5 5 5 10 ALBUQUERQUE HEIGHTS............. 63 91 64 90 / 5 5 5 10 ALBUQUERQUE VALLEY.............. 60 92 61 92 / 5 0 5 10 ALBUQUERQUE WEST MESA........... 62 91 62 91 / 5 0 5 10 LOS LUNAS....................... 60 92 62 91 / 5 5 5 10 RIO RANCHO...................... 61 93 62 92 / 5 0 5 10 SOCORRO......................... 64 94 65 94 / 10 5 10 10 SANDIA PARK/CEDAR CREST......... 56 87 59 85 / 10 5 5 20 TIJERAS......................... 57 88 59 87 / 10 5 5 20 MORIARTY/ESTANCIA............... 54 86 54 83 / 10 5 10 30 CLINES CORNERS.................. 56 85 57 86 / 10 5 5 30 GRAN QUIVIRA.................... 58 86 59 84 / 20 10 10 30 CARRIZOZO....................... 61 88 63 86 / 10 5 10 20 RUIDOSO......................... 56 82 58 81 / 20 20 20 40 CAPULIN......................... 54 86 56 83 / 40 10 5 30 RATON........................... 55 89 54 88 / 20 5 5 30 SPRINGER........................ 56 90 53 88 / 20 5 5 30 LAS VEGAS....................... 55 86 54 85 / 20 5 5 30 CLAYTON......................... 62 94 63 94 / 30 5 5 20 ROY............................. 61 90 57 88 / 20 5 5 20 CONCHAS......................... 67 97 64 96 / 20 0 0 10 SANTA ROSA...................... 64 94 62 92 / 20 5 5 20 TUCUMCARI....................... 65 99 65 99 / 20 0 0 10 CLOVIS.......................... 63 95 65 94 / 10 0 5 10 PORTALES........................ 63 96 65 95 / 10 0 5 10 FORT SUMNER..................... 66 96 66 94 / 20 0 5 10 ROSWELL......................... 67 98 67 97 / 10 0 5 10 PICACHO......................... 61 90 63 90 / 20 5 10 30 ELK............................. 58 83 63 82 / 20 10 10 40 && .ABQ WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 34
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1028 PM EDT WED AUG 6 2014 .SYNOPSIS... A SERIES OF UPPER DISTURBANCES WILL MOVE ACROSS THE NORTH COUNTRY THROUGH THURSDAY. THE FIRST WILL BE MOVING ACROSS THE REGION TONIGHT PRODUCING CLOUDS AND CHANCES FOR A FEW SHOWERS. A STRONGER UPPER DISTURBANCE WILL MOVE ACROSS THE NORTH COUNTRY THURSDAY WITH A GREATER COVERAGE OF SHOWERS AND THUNDERSTORMS...SOME OF WHICH COULD PRODUCE SMALL HAIL. A LARGE REGION OF HIGH THEN BUILDS ACROSS THE NORTH COUNTRY FRIDAY INTO THE WEEKEND WITH A STRETCH OF DRY...PLEASANT WEATHER. HIGH TEMPERATURES WILL BE IN THE 70S THURSDAY AND FRIDAY...CLIMBING BACK INTO THE LOW TO MID 80S ON SATURDAY AND SUNDAY. && .NEAR TERM /UNTIL 7 AM THURSDAY MORNING/... AS OF 1023 PM EDT WEDNESDAY...HAVE INCREASED POPS ACRS NORTHERN NY INTO PARTS OF NORTHERN VT TO LIKELY TONIGHT AND REMOVED MENTION OF THUNDER IN THIS UPDATE. ALSO...HAVE BUMPED OVERNIGHT LOWS UP SEVERAL DEGREES ACRS THE DACKS...DUE TO MORE CLOUDS/PRECIP. CRNT RADAR SHOWS A NARROW BAND OF LIGHT RAIN ACRS THE NORTHERN DACKS ATTM. THIS BAND OF RAIN WL BE ACRS THE CPV BTWN 04-06Z...INTO CENTRAL VT BTWN 05-07Z...AND THRU EASTERN SECTIONS BY 08Z. THINKING OVERALL AREAL COVERAGE AND INTENSITY OF SHOWERS WL DECREASE AFT 06Z ACRS CENTRAL/EASTERN SECTION...PER LATEST RAP13 AND HRRR COMPOSITE REFLECTIVITY PROGS. OTHERWISE...MAINLY DRY CONDITIONS WL PREVAIL ACRS RUTLAND/WINDSOR COUNTIES. TEMPS WL RANGE FROM THE U40S NEK TO LOWER 50S DACKS TO M/U 50S SLV/CPV. && .SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... AS OF 335 PM EDT WEDNESDAY...MORE UNSETTLED CONDITIONS ARE THEN EXPECTED FOR THURSDAY. A STRONGER VORT MAX COMBINED WITH COOL TEMPS ALOFT WILL FURTHER ENHANCE CLOUDINESS AND PRODUCE SHOWERS AND A FEW THUNDERSTORMS. INSTABILITY AS PROGGED BY 12Z NAM GENERALLY BETWEEN 500 TO UNDER 1000 J/KG...KEPT DOWN BY DRY DEWPOINTS IN THE 50S. SFC HEATING WILL ALSO TEND TO LOWER AS THE DAY GOES ON AS WELL AS HEATING SHOULD READILY PRODUCE CUMULUS CLOUDS GIVEN THE COOL TEMPS ALOFT. THEREFORE FEEL THREAT FOR THUNDER WOULD BE MORE OF A SLIGHT CHANCE...BUT ANY ENHANCED UPDRAFTS COULD PRODUCE GRAUPEL OR SMALL SUB-SEVERE HAIL GIVEN PRESENCE OF LOW WET BULB ZERO HEIGHTS /7-9 KFT/. HI-RES REFLECTIVITY GUIDANCE SHOWS CELLULAR ACTIVITY...WHICH MAKES SENSE AS THERE ISN`T MUCH FORCING TO SUPPORT OTHER CONVECTIVE MODES. DEEP LAYER SHEAR ALSO IS LOW. NO ENHANCED WORDING ADDED TO THE GRIDS AT THIS TIME BUT WILL MENTION IN THE HWO POTENTIAL FOR A FEW NON-SEVERE T-STORMS CAPABLE OF SUB-SEVERE HAIL. POPS TREND UPWARD THROUGH THE AFTN TO HIGH CHANCE/LIKELY WHEN BEST SYNOPTIC LIFT ASSOCIATED WITH THE SHORTWAVE AND DIURNAL HEATING OVERLAP...BEFORE LOWERING BY EVENING. QPF AMOUNTS ARE GENERALLY UNDER .25" THROUGH THE DAYLIGHT HOURS THURSDAY. COOLER HIGHS FOR THURSDAY WITH MOSTLY CLOUDY SKIES AND 850 TEMPS OF +7 TO +9C...IN THE UPPER 60S TO MID 70S...COOLEST IN EASTERN VT AND MILDER ACROSS THE ST. LAWRENCE VALLEY. CLEARING SKIES AND LIGHT SFC TO BL WINDS THURSDAY NIGHT WILL ALLOW FOR OVERNIGHT RIVER VALLEY FOG IN THE FAVORED VALLEYS. ASIDE FROM SLIGHT CHANCES FOR A FEW DIURNAL SHOWERS ACROSS THE NORTHEAST KINGDOM AREA...EXPECT FRIDAY TO BE A MOSTLY CLEAR TO PARTLY CLOUDY DAY WITH AFTN FAIR WX CUMULUS CLOUDS. 850 TEMPS WARM UP TO AROUND +10 TO +11C...WHICH SHOULD YIELD HIGHS IN THE 70S TO A FEW SPOT 80 DEGREE READINGS. ANOTHER GOOD RADIATIONAL COOLING NIGHT ANTICIPATED FRIDAY NIGHT WITH OVERNIGHT RIVER VALLEY FOG ONCE AGAIN DEVELOPING IN THE FAVORED VALLEYS...WITH LOWS RANGING IN THE MID 40S TO MID/UPPER 50S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 314 PM EDT WEDNESDAY...PRETTY QUIET WEATHER IS EXPECTED THROUGH THE LONG TERM PERIOD AS EXITING LOW PRESSURE OVER THE CANADIAN MARITIMES FRIDAY NIGHT IS REPLACED BY UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE SATURDAY WHICH WILL BRING DRY WEATHER FOR THE WEEKEND AND THROUGH MONDAY NIGHT. TEMPS WILL RUN PRETTY CLOSE TO CLIMO UNDER FULL SUNSHINE DURING THE DAY AND CLEAR SKIES AT NIGHT WITH EXPECTED HIGHS RANGING FROM THE MID 70S TO MID 80S...AND LOWS IN THE LOWER 50S TO LOWER 60S. CHANCES FOR PRECIPITATION INCREASE TUESDAY AS AN UPPER LEVEL TROUGH DIGS SOUTHWARD FROM CENTRAL CANADA INTO NEW ENGLAND DRAGGING A WEAK COLD FRONT THROUGH THE FORECAST AREA. GFS AND ECMWF ARE IN BETTER AGREEMENT TODAY ON TIMING WHICH WILL PLAY A LARGE ROLE IN THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. CURRENT PROGS ARE POINTING TOWARDS AN EVENING AND OVERNIGHT FROPA...BUT THIS FAR OUT IT`S TOO DIFFICULT TO PINPOINT. WILL CONTINUE TO HIGHLIGHT CHANCE POPS. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... THROUGH 00Z FRIDAY...GENERALLY VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH THE EXCEPTION OF BRIEF REDUCTIONS IN SCATTERED SHOWERS/ISOLATED THUNDERSTORMS AND PATCHY FOG/BR. SKIES WILL START CLEAR THIS EVENING BEFORE CLOUDS AND THE CHANCES FOR SHOWERS (ALONG WITH AN ISOLATED THUNDERSTORM) INCREASE FROM WEST TO EAST LATE THIS EVENING AND OVERNIGHT. CONDITIONS SHOULD REMAIN MAINLY VFR ALTHOUGH ANY HEAVIER SHOWER COULD BRIEFLY REDUCE VISIBILITIES. WILL SHOW WITH VCSH FOR NOW DUE TO ANTICIPATED SCATTERED NATURE. AS SHOWERS EXIT...MAY SEE A BRIEF PERIOD OF LOWER CEILINGS...AND PERHAPS EVEN SOME MVFR...ESPECIALLY SLK. MAY ALSO SEE A BRIEF PERIOD OF MVFR BR AT SLK AS WELL. CONDITIONS SHOULD IMPROVE TO VFR BY 14Z ALTHOUGH ADDITIONAL SCATTERED SHOWER/ISOLATED THUNDERSTORM DEVELOPMENT IS LIKELY ACROSS THE REGION...WITH MSS BEING LEAST-AFFECTED. LIGHT AND LOCALLY VARIABLE WINDS TONIGHT TURN NORTH/NORTHWEST 5 TO 10 KNOTS ON THURSDAY. OUTLOOK 00Z FRIDAY THROUGH MONDAY... 00Z FRI - 12Z FRI...PREDOMINANTLY VFR WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THURSDAY EVENING BRIEFLY LOWERING CONDITIONS TO MVFR AND IFR. POTENTIAL FOR IFR/LIFR FOG/BR DEVELOPMENT THURSDAY NIGHT AS WELL...ESPECIALLY AT KSLK AND KMPV. 12Z FRI - 00Z TUE...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG/BR POSSIBLE EACH NIGHT...ESPECIALLY AT KSLK AND KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...LOCONTO NEAR TERM...TABER SHORT TERM...LOCONTO LONG TERM...LAHIFF AVIATION...LAHIFF/MUCCILLI
AREA FORECAST DISCUSSION
NWS BUFFALO NY
858 PM EDT WED AUG 6 2014 .SYNOPSIS... A LINGERING UPPER LEVEL SYSTEM WILL CONTINUE TO PRODUCE WIDELY SCATTERED SHOWERS THROUGH THURSDAY MORNING. HIGH PRESSURE WILL BUILD ACROSS THE REGION THURSDAY WITH FAIR WEATHER THROUGH THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... HIGH PRESSURE ACROSS THE UPPER LAKES WILL SPREAD ACROSS THE ENTIRE GREAT LAKES REGION ON THURSDAY. ALOFT...THERE IS A FAIRLY VIGOROUS UPPER LEVEL TROUGH ACROSS EASTERN CANADA WHICH IS FORECAST TO DROP SOUTHWARD INTO MAINE BY THURSDAY. RADAR SHOWS A COUPLE BATCHES OF SHOWERS AND THUNDERSTORMS NORTH OF LAKE ONTARIO. THIS HAS FAIRLY GOOD UPPER LEVEL SUPPORT...AND FOLLOWING THE HRRR AND OTHER MESOSCALE GUIDANCE THIS WILL PROBABLY HOLD TOGETHER AND MOVE INTO THE SAINT LAWRENCE VALLEY AND NORTH COUNTRY THROUGH MIDNIGHT...BEFORE EXITING EAST DURING THE EARLY MORNING HOURS. OTHERWISE...EXPECT PATCHY FOG TONIGHT...HOWEVER DRIER AFTER AIR HAS ADVECTED INTO THE REGION LATE AFTERNOON WHICH SHOULD LIMIT FOG FORMATION WHEN COMPARED TO LAST NIGHT. FOG STILL MAY BE FAIRLY DENSE IN THE SOUTHERN TIER VALLEYS. ANOTHER SHORTWAVE MAY TOUCH OFF MORE SHOWERS IN NORTH COUNTRY AND SAINT LAWRENCE RIVER THURSDAY. OTHERWISE SCATTERED FAIR WEATHER CUMULUS CLOUDS ON THURSDAY WITH LIGHT WINDS/LAKE BREEZES. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... SIMPLY PUT...THIS PERIOD WILL FEATURE DRY AND QUIET WEATHER AS UPPER LEVEL TROUGHING OVER NEW ENGLAND SLIDES EAST TO NEWFOUNDLAND...WHILE RIDGING/SUBSIDENCE/DRIER AIR BUILDS ACROSS NEW YORK STATE AT ALL LEVELS IN ITS WAKE. AT THE SAME TIME...GRADUAL WARMING OF OUR AIRMASS WILL ALLOW TEMPERATURES TO RECOVER FROM INITIALLY SLIGHTLY BELOW NORMAL LEVELS TO RIGHT AROUND SEASONAL AVERAGES BY SATURDAY. THIS WILL TRANSLATE INTO DAYTIME HIGHS CLIMBING BACK TO AROUND 80 BY SATURDAY...AND NIGHTTIME LOWS RECOVERING BACK INTO THE MID 50S TO LOWER 60S. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... THE FIRST TWO DAYS OF THE LONG TERM PERIOD SHOULD CONTINUE TO FEATURE UNEVENTFUL WEATHER AS UPPER LEVEL RIDGING SLOWLY BUILDS EAST INTO NEW ENGLAND...WHILE THE AXIS OF ITS ATTENDANT SURFACE RIDGE SLOWLY DRIFTS EAST TO A POSITION JUST OFFSHORE OF THE ATLANTIC COASTLINE. WHILE A STRAY SHOWER OR STORM STILL CANNOT BE TOTALLY RULED OUT ACROSS THE SOUTHERN TIER MONDAY AFTERNOON AS DAYTIME HEATING INTERACTS WITH SLOWLY INCREASING MOISTURE RETURNING AROUND THE BACKSIDE OF THE DEPARTING SURFACE RIDGE...BY AND LARGE CONDITIONS SHOULD REMAIN DRY RIGHT THROUGH MONDAY. AFTER THAT...THE MEDIUM RANGE GUIDANCE REMAINS IN DECENT AGREEMENT THAT THE NEXT MID AND UPPER-LEVEL TROUGH WILL WORK ACROSS THE LOWER GREAT LAKES AND NORTHEAST NEXT TUESDAY AND WEDNESDAY. THIS WILL GENERALLY RESULT IN A RENEWED OPPORTUNITY FOR SOME SHOWERS AND THUNDERSTORMS...THOUGH HAVE KEPT POPS CONFINED TO THE LOW CHANCE RANGE FOR NOW GIVEN BOTH THE DISTANT TIME FRAME...AND THE USUAL MODEL DIFFERENCES IN THE TIMING/STRENGTH OF THIS FEATURE THIS FAR OUT. WITH RESPECT TO TEMPERATURES...THESE WILL REMAIN NEAR NORMAL THROUGH AT LEAST MONDAY WITH DAYTIME HIGHS MOSTLY REACHING INTO THE LOWER 80S...AND NIGHTTIME LOWS DROPPING INTO THE UPPER 50S TO MID 60S. BEGINNING TUESDAY...READINGS MAY DROP OFF A LITTLE WITH THE ARRIVAL OF THE TROUGH...THOUGH THESE WILL BE UNLIKELY TO DROP MORE THAN A FEW DEGREES FROM SEASONAL AVERAGES. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE BUILDING FROM THE UPPER LAKES WILL RESULT IN SCT-BKN HIGH CLOUDS AT MOST TAF LOCATIONS. SCATTERED SHOWERS AND POSSIBLY A THUNDERSTORM MAY BRIEFLY IMPACT ART...WITH THE BEST CHANCE OF THIS LATE THIS EVENING. OTHERWISE...EXPECT MAINLY FAIR WEATHER OVERNIGHT AND THURSDAY. FOG IS LIKELY TO DEVELOP TONIGHT...BUT SHOULD MAINLY BE CONFINED TO THE SOUTHERN TIER VALLEYS (SUCH AS JHW)...WHERE A PERIOD OF DENSE FOG IS POSSIBLE. LIGHT WINDS/LAKE BREEZES ON THURSDAY WITH SCATTERED CU...BASES 3-4K FT. OUTLOOK... THURSDAY NIGHT THROUGH MONDAY...OTHER THAN OVERNIGHT DENSE VALLEY FOG IN THE SOUTHERN TIER...NO SIGNIFICANT WEATHER EXPECTED. && .MARINE... LIGHT WINDS AND LOW SIGNIFICANT WAVE HEIGHTS ARE EXPECTED THROUGH THE END OF THE WEEK. CONDITIONS WILL BECOME MARGINALLY FAVORABLE FOR WATERSPOUTS ACROSS LAKE ONTARIO LATE TONIGHT INTO THURSDAY MORNING AS AN UPPER TROUGH DROPS ACROSS THE WATERS AND COOLS TEMPERATURES ALOFT AND SPARKS A FEW SHOWERS AND POSSIBLY WATERSPOUTS. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...FRANKLIN NEAR TERM...APFFEL/FRANKLIN SHORT TERM...JJR LONG TERM...JJR AVIATION...APFFEL MARINE...APFFEL/FRANKLIN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
731 PM EDT WED AUG 6 2014 .SYNOPSIS... A SERIES OF UPPER DISTURBANCES WILL MOVE ACROSS THE NORTH COUNTRY THROUGH THURSDAY. THE FIRST WILL BE MOVING ACROSS THE REGION TONIGHT PRODUCING CLOUDS AND CHANCES FOR A FEW SHOWERS. A STRONGER UPPER DISTURBANCE WILL MOVE ACROSS THE NORTH COUNTRY THURSDAY WITH A GREATER COVERAGE OF SHOWERS AND THUNDERSTORMS...SOME OF WHICH COULD PRODUCE SMALL HAIL. A LARGE REGION OF HIGH THEN BUILDS ACROSS THE NORTH COUNTRY FRIDAY INTO THE WEEKEND WITH A STRETCH OF DRY...PLEASANT WEATHER. HIGH TEMPERATURES WILL BE IN THE 70S THURSDAY AND FRIDAY...CLIMBING BACK INTO THE LOW TO MID 80S ON SATURDAY AND SUNDAY. && .NEAR TERM /UNTIL 7 AM THURSDAY MORNING/... AS OF 706 PM EDT WEDNESDAY...A FEW TWEAKS TO POPS...CLOUD COVER AND TEMPS WITH THIS UPDATE. I HAVE INCREASED POPS ACRS NORTHERN NY...THE CPV...AND MOST OF NORTHERN/CENTRAL VT TONIGHT. WATER VAPOR SHOWS POTENT 5H VORT DIVING SOUTHEAST TWD THE SLV ATTM...WITH SOME LIGHTNING ACTIVITY NOTED WITH THIS FEATURE. LATEST HRRR...RAP13...AND BTV 4KM SHOW SOME WEAK INSTABILITY WITH CAPE VALUES BTWN 200 AND 500 J/KG ACRS NORTHERN NY INTO THE CPV OVERNIGHT...COMBINED WITH DYNAMICS ALOFT THINKING A FEW RUMBLES OF THUNDER WL BE POSSIBLE. HAVE INCLUDED IN FCST FOR NORTHERN NY. TIMING THE PRECIP HAS IT ARRIVING BTWN 0130 AND 0230 ACRS THE SLV...BTWN 0230 AND 0430Z DACKS AND INTO THE CPV AFT 05Z AND THRU NORTHERN VT BTWN 07-09Z. WL MENTION CHC POPS ACRS THESE REGIONS WITH SCHC ACRS SOUTHERN SECTIONS OF OUR CWA. NEXT QUESTION WL BE AREAL COVERAGE OF FOG...THINKING CT RIVER VALLEY WL SEE THE LONGEST DURATION OF CLR SKIES AND HAVE THE BEST POTENTIAL FOR FOG WITH SOME PATCHY AREAS ACRS THE DEEPER MTN VALLEYS NEAR WARMER WATER AREA OF CENTRAL/NORTHERN VT. TEMPS WL DROP BACK INTO THE U40S NEK/SLK TO M/U 50S SLV/CPV. ALL IS COVERED WELL IN CRNT FCST. A GENERALLY PLEASANT AFTN ACROSS THE NORTH COUNTRY WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES...COMFORTABLE DEWPOINTS FALLING INTO THE 50S AND A NORTHERLY BREEZE IN PLACE. HOWEVER...A BROAD LONGWAVE TROUGH IS ESTABLISHING ITSELF ACROSS MUCH OF NORTHEASTERN NOAM...AND THE FIRST OF A SERIES OF WEAK VORT MAXIMA WILL APPROACH THE NORTH COUNTRY BY LATER TONIGHT. THIS INITIAL SHORTWAVE TROUGH/ASSOCIATED VORT MAX IS NOW PRODUCING A SHIELD OF ENHANCED CLOUDINESS OVER THE OTTAWA VALLEY...THOSE CLOUDS MOST APPARENT IN 12Z BTV-4/15Z RAP AS A RIBBON OF 850-700MB RH. SOME MODEST PROGGED VERTICAL MOTION IN THAT LAYER AS WELL. SO EXPECT AN INCREASE IN CLOUDS WITH CHANCES FOR LIGHT SHOWERS - WITH THE BEST CHANCE OF SHOWERS AFTER MIDNIGHT AND PRIMARILY CONFINED TO NORTHERN NEW YORK. LITTLE IN THE WAY OF QPF WITH THE SHOWERS...A FEW HUNDRETHS OF AN INCH. SKIES WILL TEND TO BE CLEAREST ACROSS EASTERN VT/CT RIVER VALLEY WHICH WILL ALLOW FOR RIVER VALLEY FOG TO DEVELOP ACROSS THIS GENERAL AREA OVERNIGHT. TEMPS WILL LIKELY DROP OFF QUICKLY EARLY THIS EVENING UNDER DRY CONDITIONS...BUT COOLING WILL TEND TO LEVEL OFF A BIT ACROSS THE NORTHERN HALF OF THE CWA. I OPTED TO TREND TEMPS CLOSER TO WARMER SIDE OF AVAILABLE GUIDANCE GIVEN EXPECTED CLOUDINESS...GENERALLY IN THE 40S TO MID/UPPER 50S IN THE VALLEYS. LOWS GENERALLY COOLEST IN THE `DACKS AND ACROSS EASTERN VERMONT. && .SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... AS OF 335 PM EDT WEDNESDAY...MORE UNSETTLED CONDITIONS ARE THEN EXPECTED FOR THURSDAY. A STRONGER VORT MAX COMBINED WITH COOL TEMPS ALOFT WILL FURTHER ENHANCE CLOUDINESS AND PRODUCE SHOWERS AND A FEW THUNDERSTORMS. INSTABILITY AS PROGGED BY 12Z NAM GENERALLY BETWEEN 500 TO UNDER 1000 J/KG...KEPT DOWN BY DRY DEWPOINTS IN THE 50S. SFC HEATING WILL ALSO TEND TO LOWER AS THE DAY GOES ON AS WELL AS HEATING SHOULD READILY PRODUCE CUMULUS CLOUDS GIVEN THE COOL TEMPS ALOFT. THEREFORE FEEL THREAT FOR THUNDER WOULD BE MORE OF A SLIGHT CHANCE...BUT ANY ENHANCED UPDRAFTS COULD PRODUCE GRAUPEL OR SMALL SUB-SEVERE HAIL GIVEN PRESENCE OF LOW WET BULB ZERO HEIGHTS /7-9 KFT/. HI-RES REFLECTIVITY GUIDANCE SHOWS CELLULAR ACTIVITY...WHICH MAKES SENSE AS THERE ISN`T MUCH FORCING TO SUPPORT OTHER CONVECTIVE MODES. DEEP LAYER SHEAR ALSO IS LOW. NO ENHANCED WORDING ADDED TO THE GRIDS AT THIS TIME BUT WILL MENTION IN THE HWO POTENTIAL FOR A FEW NON-SEVERE T-STORMS CAPABLE OF SUB-SEVERE HAIL. POPS TREND UPWARD THROUGH THE AFTN TO HIGH CHANCE/LIKELY WHEN BEST SYNOPTIC LIFT ASSOCIATED WITH THE SHORTWAVE AND DIURNAL HEATING OVERLAP...BEFORE LOWERING BY EVENING. QPF AMOUNTS ARE GENERALLY UNDER .25" THROUGH THE DAYLIGHT HOURS THURSDAY. COOLER HIGHS FOR THURSDAY WITH MOSTLY CLOUDY SKIES AND 850 TEMPS OF +7 TO +9C...IN THE UPPER 60S TO MID 70S...COOLEST IN EASTERN VT AND MILDER ACROSS THE ST. LAWRENCE VALLEY. CLEARING SKIES AND LIGHT SFC TO BL WINDS THURSDAY NIGHT WILL ALLOW FOR OVERNIGHT RIVER VALLEY FOG IN THE FAVORED VALLEYS. ASIDE FROM SLIGHT CHANCES FOR A FEW DIURNAL SHOWERS ACROSS THE NORTHEAST KINGDOM AREA...EXPECT FRIDAY TO BE A MOSTLY CLEAR TO PARTLY CLOUDY DAY WITH AFTN FAIR WX CUMULUS CLOUDS. 850 TEMPS WARM UP TO AROUND +10 TO +11C...WHICH SHOULD YIELD HIGHS IN THE 70S TO A FEW SPOT 80 DEGREE READINGS. ANOTHER GOOD RADIATIONAL COOLING NIGHT ANTICIPATED FRIDAY NIGHT WITH OVERNIGHT RIVER VALLEY FOG ONCE AGAIN DEVELOPING IN THE FAVORED VALLEYS...WITH LOWS RANGING IN THE MID 40S TO MID/UPPER 50S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 314 PM EDT WEDNESDAY...PRETTY QUIET WEATHER IS EXPECTED THROUGH THE LONG TERM PERIOD AS EXITING LOW PRESSURE OVER THE CANADIAN MARITIMES FRIDAY NIGHT IS REPLACED BY UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE SATURDAY WHICH WILL BRING DRY WEATHER FOR THE WEEKEND AND THROUGH MONDAY NIGHT. TEMPS WILL RUN PRETTY CLOSE TO CLIMO UNDER FULL SUNSHINE DURING THE DAY AND CLEAR SKIES AT NIGHT WITH EXPECTED HIGHS RANGING FROM THE MID 70S TO MID 80S...AND LOWS IN THE LOWER 50S TO LOWER 60S. CHANCES FOR PRECIPITATION INCREASE TUESDAY AS AN UPPER LEVEL TROUGH DIGS SOUTHWARD FROM CENTRAL CANADA INTO NEW ENGLAND DRAGGING A WEAK COLD FRONT THROUGH THE FORECAST AREA. GFS AND ECMWF ARE IN BETTER AGREEMENT TODAY ON TIMING WHICH WILL PLAY A LARGE ROLE IN THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. CURRENT PROGS ARE POINTING TOWARDS AN EVENING AND OVERNIGHT FROPA...BUT THIS FAR OUT IT`S TOO DIFFICULT TO PINPOINT. WILL CONTINUE TO HIGHLIGHT CHANCE POPS. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... THROUGH 00Z FRIDAY...GENERALLY VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS WITH THE EXCEPTION OF BRIEF REDUCTIONS IN SCATTERED SHOWERS/ISOLATED THUNDERSTORMS AND PATCHY FOG/BR. SKIES WILL START CLEAR THIS EVENING BEFORE CLOUDS AND THE CHANCES FOR SHOWERS (ALONG WITH AN ISOLATED THUNDERSTORM) INCREASE FROM WEST TO EAST LATE THIS EVENING AND OVERNIGHT. CONDITIONS SHOULD REMAIN MAINLY VFR ALTHOUGH ANY HEAVIER SHOWER COULD BRIEFLY REDUCE VISIBILITIES. WILL SHOW WITH VCSH FOR NOW DUE TO ANTICIPATED SCATTERED NATURE. AS SHOWERS EXIT...MAY SEE A BRIEF PERIOD OF LOWER CEILINGS...AND PERHAPS EVEN SOME MVFR...ESPECIALLY SLK. MAY ALSO SEE A BRIEF PERIOD OF MVFR BR AT SLK AS WELL. CONDITIONS SHOULD IMPROVE TO VFR BY 14Z ALTHOUGH ADDITIONAL SCATTERED SHOWER/ISOLATED THUNDERSTORM DEVELOPMENT IS LIKELY ACROSS THE REGION...WITH MSS BEING LEAST-AFFECTED. LIGHT AND LOCALLY VARIABLE WINDS TONIGHT TURN NORTH/NORTHWEST 5 TO 10 KNOTS ON THURSDAY. OUTLOOK 00Z FRIDAY THROUGH MONDAY... 00Z FRI - 12Z FRI...PREDOMINANTLY VFR WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THURSDAY EVENING BRIEFLY LOWERING CONDITIONS TO MVFR AND IFR. POTENTIAL FOR IFR/LIFR FOG/BR DEVELOPMENT THURSDAY NIGHT AS WELL...ESPECIALLY AT KSLK AND KMPV. 12Z FRI - 00Z TUE...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG/BR POSSIBLE EACH NIGHT...ESPECIALLY AT KSLK AND KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...LOCONTO NEAR TERM...TABER/LOCONTO SHORT TERM...LOCONTO LONG TERM...LAHIFF AVIATION...LAHIFF/MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
716 PM EDT WED AUG 6 2014 .SYNOPSIS... A SERIES OF UPPER DISTURBANCES WILL MOVE ACROSS THE NORTH COUNTRY THROUGH THURSDAY. THE FIRST WILL BE MOVING ACROSS THE REGION TONIGHT PRODUCING CLOUDS AND CHANCES FOR A FEW SHOWERS. A STRONGER UPPER DISTURBANCE WILL MOVE ACROSS THE NORTH COUNTRY THURSDAY WITH A GREATER COVERAGE OF SHOWERS AND THUNDERSTORMS...SOME OF WHICH COULD PRODUCE SMALL HAIL. A LARGE REGION OF HIGH THEN BUILDS ACROSS THE NORTH COUNTRY FRIDAY INTO THE WEEKEND WITH A STRETCH OF DRY...PLEASANT WEATHER. HIGH TEMPERATURES WILL BE IN THE 70S THURSDAY AND FRIDAY...CLIMBING BACK INTO THE LOW TO MID 80S ON SATURDAY AND SUNDAY. && .NEAR TERM /UNTIL 7 AM THURSDAY MORNING/... AS OF 706 PM EDT WEDNESDAY...A FEW TWEAKS TO POPS...CLOUD COVER AND TEMPS WITH THIS UPDATE. I HAVE INCREASED POPS ACRS NORTHERN NY...THE CPV...AND MOST OF NORTHERN/CENTRAL VT TONIGHT. WATER VAPOR SHOWS POTENT 5H VORT DIVING SOUTHEAST TWD THE SLV ATTM...WITH SOME LIGHTNING ACTIVITY NOTED WITH THIS FEATURE. LATEST HRRR...RAP13...AND BTV 4KM SHOW SOME WEAK INSTABILITY WITH CAPE VALUES BTWN 200 AND 500 J/KG ACRS NORTHERN NY INTO THE CPV OVERNIGHT...COMBINED WITH DYNAMICS ALOFT THINKING A FEW RUMBLES OF THUNDER WL BE POSSIBLE. HAVE INCLUDED IN FCST FOR NORTHERN NY. TIMING THE PRECIP HAS IT ARRIVING BTWN 0130 AND 0230 ACRS THE SLV...BTWN 0230 AND 0430Z DACKS AND INTO THE CPV AFT 05Z AND THRU NORTHERN VT BTWN 07-09Z. WL MENTION CHC POPS ACRS THESE REGIONS WITH SCHC ACRS SOUTHERN SECTIONS OF OUR CWA. NEXT QUESTION WL BE AREAL COVERAGE OF FOG...THINKING CT RIVER VALLEY WL SEE THE LONGEST DURATION OF CLR SKIES AND HAVE THE BEST POTENTIAL FOR FOG WITH SOME PATCHY AREAS ACRS THE DEEPER MTN VALLEYS NEAR WARMER WATER AREA OF CENTRAL/NORTHERN VT. TEMPS WL DROP BACK INTO THE U40S NEK/SLK TO M/U 50S SLV/CPV. ALL IS COVERED WELL IN CRNT FCST. A GENERALLY PLEASANT AFTN ACROSS THE NORTH COUNTRY WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES...COMFORTABLE DEWPOINTS FALLING INTO THE 50S AND A NORTHERLY BREEZE IN PLACE. HOWEVER...A BROAD LONGWAVE TROUGH IS ESTABLISHING ITSELF ACROSS MUCH OF NORTHEASTERN NOAM...AND THE FIRST OF A SERIES OF WEAK VORT MAXIMA WILL APPROACH THE NORTH COUNTRY BY LATER TONIGHT. THIS INITIAL SHORTWAVE TROUGH/ASSOCIATED VORT MAX IS NOW PRODUCING A SHIELD OF ENHANCED CLOUDINESS OVER THE OTTAWA VALLEY...THOSE CLOUDS MOST APPARENT IN 12Z BTV-4/15Z RAP AS A RIBBON OF 850-700MB RH. SOME MODEST PROGGED VERTICAL MOTION IN THAT LAYER AS WELL. SO EXPECT AN INCREASE IN CLOUDS WITH CHANCES FOR LIGHT SHOWERS - WITH THE BEST CHANCE OF SHOWERS AFTER MIDNIGHT AND PRIMARILY CONFINED TO NORTHERN NEW YORK. LITTLE IN THE WAY OF QPF WITH THE SHOWERS...A FEW HUNDRETHS OF AN INCH. SKIES WILL TEND TO BE CLEAREST ACROSS EASTERN VT/CT RIVER VALLEY WHICH WILL ALLOW FOR RIVER VALLEY FOG TO DEVELOP ACROSS THIS GENERAL AREA OVERNIGHT. TEMPS WILL LIKELY DROP OFF QUICKLY EARLY THIS EVENING UNDER DRY CONDITIONS...BUT COOLING WILL TEND TO LEVEL OFF A BIT ACROSS THE NORTHERN HALF OF THE CWA. I OPTED TO TREND TEMPS CLOSER TO WARMER SIDE OF AVAILABLE GUIDANCE GIVEN EXPECTED CLOUDINESS...GENERALLY IN THE 40S TO MID/UPPER 50S IN THE VALLEYS. LOWS GENERALLY COOLEST IN THE `DACKS AND ACROSS EASTERN VERMONT. && .SHORT TERM /7 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/... AS OF 335 PM EDT WEDNESDAY...MORE UNSETTLED CONDITIONS ARE THEN EXPECTED FOR THURSDAY. A STRONGER VORT MAX COMBINED WITH COOL TEMPS ALOFT WILL FURTHER ENHANCE CLOUDINESS AND PRODUCE SHOWERS AND A FEW THUNDERSTORMS. INSTABILITY AS PROGGED BY 12Z NAM GENERALLY BETWEEN 500 TO UNDER 1000 J/KG...KEPT DOWN BY DRY DEWPOINTS IN THE 50S. SFC HEATING WILL ALSO TEND TO LOWER AS THE DAY GOES ON AS WELL AS HEATING SHOULD READILY PRODUCE CUMULUS CLOUDS GIVEN THE COOL TEMPS ALOFT. THEREFORE FEEL THREAT FOR THUNDER WOULD BE MORE OF A SLIGHT CHANCE...BUT ANY ENHANCED UPDRAFTS COULD PRODUCE GRAUPEL OR SMALL SUB-SEVERE HAIL GIVEN PRESENCE OF LOW WET BULB ZERO HEIGHTS /7-9 KFT/. HI-RES REFLECTIVITY GUIDANCE SHOWS CELLULAR ACTIVITY...WHICH MAKES SENSE AS THERE ISN`T MUCH FORCING TO SUPPORT OTHER CONVECTIVE MODES. DEEP LAYER SHEAR ALSO IS LOW. NO ENHANCED WORDING ADDED TO THE GRIDS AT THIS TIME BUT WILL MENTION IN THE HWO POTENTIAL FOR A FEW NON-SEVERE T-STORMS CAPABLE OF SUB-SEVERE HAIL. POPS TREND UPWARD THROUGH THE AFTN TO HIGH CHANCE/LIKELY WHEN BEST SYNOPTIC LIFT ASSOCIATED WITH THE SHORTWAVE AND DIURNAL HEATING OVERLAP...BEFORE LOWERING BY EVENING. QPF AMOUNTS ARE GENERALLY UNDER .25" THROUGH THE DAYLIGHT HOURS THURSDAY. COOLER HIGHS FOR THURSDAY WITH MOSTLY CLOUDY SKIES AND 850 TEMPS OF +7 TO +9C...IN THE UPPER 60S TO MID 70S...COOLEST IN EASTERN VT AND MILDER ACROSS THE ST. LAWRENCE VALLEY. CLEARING SKIES AND LIGHT SFC TO BL WINDS THURSDAY NIGHT WILL ALLOW FOR OVERNIGHT RIVER VALLEY FOG IN THE FAVORED VALLEYS. ASIDE FROM SLIGHT CHANCES FOR A FEW DIURNAL SHOWERS ACROSS THE NORTHEAST KINGDOM AREA...EXPECT FRIDAY TO BE A MOSTLY CLEAR TO PARTLY CLOUDY DAY WITH AFTN FAIR WX CUMULUS CLOUDS. 850 TEMPS WARM UP TO AROUND +10 TO +11C...WHICH SHOULD YIELD HIGHS IN THE 70S TO A FEW SPOT 80 DEGREE READINGS. ANOTHER GOOD RADIATIONAL COOLING NIGHT ANTICIPATED FRIDAY NIGHT WITH OVERNIGHT RIVER VALLEY FOG ONCE AGAIN DEVELOPING IN THE FAVORED VALLEYS...WITH LOWS RANGING IN THE MID 40S TO MID/UPPER 50S. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 314 PM EDT WEDNESDAY...PRETTY QUIET WEATHER IS EXPECTED THROUGH THE LONG TERM PERIOD AS EXITING LOW PRESSURE OVER THE CANADIAN MARITIMES FRIDAY NIGHT IS REPLACED BY UPPER LEVEL RIDGING AND SURFACE HIGH PRESSURE SATURDAY WHICH WILL BRING DRY WEATHER FOR THE WEEKEND AND THROUGH MONDAY NIGHT. TEMPS WILL RUN PRETTY CLOSE TO CLIMO UNDER FULL SUNSHINE DURING THE DAY AND CLEAR SKIES AT NIGHT WITH EXPECTED HIGHS RANGING FROM THE MID 70S TO MID 80S...AND LOWS IN THE LOWER 50S TO LOWER 60S. CHANCES FOR PRECIPITATION INCREASE TUESDAY AS AN UPPER LEVEL TROUGH DIGS SOUTHWARD FROM CENTRAL CANADA INTO NEW ENGLAND DRAGGING A WEAK COLD FRONT THROUGH THE FORECAST AREA. GFS AND ECMWF ARE IN BETTER AGREEMENT TODAY ON TIMING WHICH WILL PLAY A LARGE ROLE IN THE POTENTIAL FOR THUNDERSTORM DEVELOPMENT. CURRENT PROGS ARE POINTING TOWARDS AN EVENING AND OVERNIGHT FROPA...BUT THIS FAR OUT IT`S TOO DIFFICULT TO PINPOINT. WILL CONTINUE TO HIGHLIGHT CHANCE POPS. && .AVIATION /23Z WEDNESDAY THROUGH MONDAY/... THROUGH 18Z THURSDAY...VFR CONDITIONS EXPECTED THROUGH THE NEXT 24 HOURS. SCATTERED TO BROKEN LOW/MID LEVEL CLOUDS ACROSS THE ADIRONDACKS AND VERMONT WILL DISSIPATE LATE THIS AFTERNOON INTO THE EVENING HOURS BEFORE ANOTHER ROUND MID LEVEL CLOUDS SPREADS OVER THE REGION OVERNIGHT. COULD SEE A FEW SHOWERS ASSOCIATED WITH THIS CLOUD COVER MOVING IN ACROSS NORTHERN NEW YORK OVERNIGHT...BUT OVERALL BETTER CHANCES FOR SHOWERS AND STORMS COMES LATER THURSDAY AFTERNOON FROM KSLK EASTWARD. OUTLOOK 18Z THURSDAY THROUGH MONDAY... 18Z THU - 12Z FRI...PREDOMINANTLY VFR WITH SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS THURSDAY AFTERNOON AND EVENING BRIEFLY LOWERING CONDITIONS TO MVFR AND IFR. POTENTIAL FOR IFR/LIFR FOG/BR DEVELOPMENT THURSDAY NIGHT AS WELL...ESPECIALLY AT KSLK AND KMPV. 12Z FRI - 00Z TUE...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG/BR POSSIBLE EACH NIGHT...ESPECIALLY AT KSLK AND KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...LOCONTO NEAR TERM...TABER/LOCONTO SHORT TERM...LOCONTO LONG TERM...LAHIFF AVIATION...LAHIFF
AREA FORECAST DISCUSSION
NWS BUFFALO NY
532 PM EDT TUE AUG 5 2014 .SYNOPSIS... A COLD FRONT WILL CROSS THE REGION TONIGHT...BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WITH SLIGHTLY COOLER AIR WILL MOVE ACROSS THE REGION BEHIND THE FRONT. A FEW SHOWERS MAY STILL LINGER ON WEDNESDAY BEFORE DRY WEATHER RETURNS BY THE END OF THE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... A MODEST SHORTWAVE WILL DIG INTO THE BASE OF A MEAN UPPER LEVEL TROUGH OVER EASTERN CANADA/NEW ENGLAND TONIGHT. RADAR SHOWS A SLUG OF SHOWERS AND THUNDERSTORMS ACROSS CENTRAL NEW YORK BRINGING LOCALLY HEAVY RAINFALL. THE HRRR HAS THIS AREA WELL HANDLED...AND IS SUPPORTED BY SATELLITE TRENDS IN MOVING THIS AREA EAST OF OUR CWA JUST BEFORE SUNSET. THERE MAY BE A FEW SHOWERS AND THUNDERSTORMS THAT DEVELOP ACROSS THE ST LAWRENCE...BUT OTHER THAN THIS IT APPEARS ANY OTHER SHOWERS BEHIND THIS SHOULD BE FAIRLY SPARSE. EXPECT CLOUDS TO LINGER IN MOST AREAS...BUT THERE MAY BE SOME CLEARING IN WESTERN PORTIONS WHICH COULD RESULT IN PATCHY FOG. HIGH PRESSURE BUILDS DOWN BEHIND THE FRONT LATER TONIGHT AND A NOTABLE AREA OF SUBSIDENCE DEVELOPS ACROSS THE AREA IN ITS WAKE. CLOUDS WILL GRADUALLY DECREASE ON WEDNESDAY...HOWEVER SCATTERED CONVECTION POSSIBLE SOUTHERN TIER LATE WEDNESDAY MORNING INTO THE AFTERNOON IN CLOSER PROXIMITY TO COLD FRONT. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... BETWEEN WEDNESDAY NIGHT AND THURSDAY...THE PERSISTENT UPPER LEVEL TROUGHING THAT HAS PLAGUED OUR REGION FOR MUCH OF THE PAST WEEK AND A HALF WILL FINALLY BEGIN TO SLIDE EAST INTO NEW ENGLAND...WHILE SURFACE HIGH PRESSURE AND DRIER AIR SLOWLY BUILDS EASTWARD FROM THE CENTRAL GREAT LAKES. WHILE THIS SHOULD RESULT IN DRY WEATHER FOR THE MAJORITY OF OUR AREA...THE EASTERN FINGER LAKES AND NORTH COUNTRY WILL BE SUBJECT TO ONE MORE ROUND OF SCATTERED SHOWERS/THUNDERSTORMS AS ONE FINAL SHORTWAVE IMPULSE DROPS THROUGH THE BACKSIDE OF THE DEPARTING TROUGH...WITH THE BULK OF THESE LIKELY COMING BETWEEN LATER WEDNESDAY NIGHT AND EARLY THURSDAY AFTERNOON. AFTER THAT...THE REMAINDER OF THE PERIOD SHOULD FEATURE DRY AND QUIET WEATHER AS THE UPPER TROUGH FINALLY SLIDES EAST INTO NEW ENGLAND AND THE CANADIAN MARITIMES...AND THE AFOREMENTIONED SURFACE RIDGE SETTLES DIRECTLY ACROSS THE LOWER GREAT LAKES. WITH RESPECT TO TEMPERATURES...READINGS WILL CONTINUE TO AVERAGE A LITTLE BELOW NORMAL THROUGH THE END OF THE WORK WEEK...WITH DAYTIME HIGHS LARGELY IN THE MID 70S AND NIGHTTIME LOWS RANGING THROUGH THE 50S...THOUGH SOME INTERIOR PORTIONS OF THE SOUTHERN TIER COULD SEE LOWS IN THE UPPER 40S THURSDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... THE FIRST THREE DAYS OF THE LONG TERM PERIOD STILL LOOKS TO FEATURE A WELCOME PERIOD OF UNEVENTFUL WEATHER AS UPPER LEVEL RIDGING BUILDS EASTWARD ACROSS THE LOWER GREAT LAKES AND INTO NEW YORK STATE AND NEW ENGLAND...WHILE THE AXIS OF ITS ATTENDANT SURFACE RIDGE SLOWLY DRIFTS EAST TO A POSITION JUST OFF THE ATLANTIC COASTLINE. WHILE A STRAY SHOWER OR STORM CANNOT BE TOTALLY RULED OUT ACROSS THE SOUTHERN TIER SUNDAY/MONDAY AFTERNOONS AS DAYTIME HEATING INTERACTS WITH SLOWLY INCREASING MOISTURE RETURNING AROUND THE BACKSIDE OF THE DEPARTING SURFACE RIDGE...THIS PORTION OF THE PERIOD SHOULD LARGELY FEATURE DRY AND FAIR WEATHER. WITH A GRADUAL WARMING OF OUR AIRMASS TAKING PLACE...TEMPS SHOULD ALSO RECOVER BACK TO NORMAL LEVELS WITH DAYTIME HIGHS REACHING INTO THE UPPER 70S/LOWER 80S EACH DAY...AND NIGHTTIME LOWS LARGELY RANGING IN THE MID 50S TO LOWER 60S. LATE IN THE PERIOD...THE NEXT NOTEWORTHY MID-LEVEL IMPULSE WILL WORK INTO THE LOWER GREAT LAKES. WHILE THE GFS/ECMWF DIFFER NOTICEABLY ON THE SPEED AND STRENGTH OF THIS FEATURE...BOTH SUGGEST GENERAL CHANCES OF SHOWERS AND THUNDERSTORMS RETURNING TO THE AREA BY NEXT TUESDAY. WITH THIS IN MIND...HAVE INTRODUCED SOME LOW CHANCE POPS FOR THE NEW DAY 7...WITH TEMPERATURES OTHERWISE REMAINING NEAR NORMAL LEVELS TO CLOSE OUT THE EXTENDED PORTION OF THE FORECAST. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... SLUG OF SHOWERS AND THUNDERSTORMS WILL CONTINUE TO MOVE EAST AND AWAY FROM OUR TAF SITES. SCATTERED TSTMS MAY CLIP ART...OTHERWISE EXPECT TAF SITES TO STAY DRY OVERNIGHT. BEHIND THIS...THE MAIN CONCERN WILL BE FOG DEVELOPMENT. FOR THE MOST PART...EXPECT LINGERING MOISTURE TO RESULT IN VFR-MVFR CIGS OVERNIGHT...HOWEVER IF THERE IS ANY CLEARING IT WILL NOT TAKE LONG FOR FOG TO DEVELOP GIVEN TIGHT TEMP-DEW POINT SPREADS. LEFTOVER CLOUDS WILL REMAIN OVERNIGHT INTO EARLY WEDNESDAY WITH ISOLATED -SHRA ESPECIALLY ACROSS THE SOUTHERN TIER. DRIER AIR ADVECTS SOUTHWARD ON WEDNESDAY WITH CLOUDS GRADUALLY DECREASING. SCATTERED CONVECTION POSSIBLE SOUTHERN TIER 14-20Z WEDNESDAY IN CLOSER PROXIMITY TO COLD FRONT. OUTLOOK... WEDNESDAY NIGHT THROUGH SUNDAY...OTHER THAN VALLEY FOG...NO SIGNIFICANT WEATHER EXPECTED. && .MARINE... A COLD FRONT WILL CROSS THE LOWER GREAT LAKES TONIGHT BRINGING SCATTERED SHOWERS AND THUNDERSTORMS. OTHERWISE...FEW CONCERNS FOR MARINE PURPOSES...AS LIGHT WINDS AND LOW SIGNIFICANT WAVE HEIGHTS ARE EXPECTED THROUGH THE THE END OF THE WEEK. && .BUF WATCHES/WARNINGS/ADVISORIES... NY...NONE. MARINE...NONE. && $$ SYNOPSIS...FRANKLIN NEAR TERM...APFFEL/FRANKLIN SHORT TERM...JJR LONG TERM...JJR AVIATION...APFFEL/FRANKLIN MARINE...FRANKLIN
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
129 PM EDT TUE AUG 5 2014 .SYNOPSIS... A COLD FRONT SHIFTING SOUTHEASTWARD FROM ONTARIO AND QUEBEC WILL BRING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO THE NORTH COUNTRY THIS AFTERNOON. A FEW STRONGER STORMS ARE POSSIBLE...WITH BRIEF HEAVY DOWNPOURS AND SMALL HAIL. THE FRONT CLEARS THE AREA TO THE SOUTH SETTING UP A PLEASANT DAY ON WEDNESDAY WITH LOWER HUMIDITY LEVELS AND HIGH TEMPERATURES MAINLY IN THE MID TO UPPER 70S. AN UPPER-LEVEL DISTURBANCE WILL BRING ADDITIONAL SHOWERS AND ISOLATED THUNDERSTORMS TO THE REGION FOR THURSDAY AFTERNOON. ACTIVITY WILL BE MOST WIDESPREAD ACROSS VERMONT. GENERALLY FAIR CONDITIONS ARE EXPECTED WITH HIGH PRESSURE ON FRIDAY AND THROUGH THE WEEKEND...WITH AFTERNOON TEMPERATURES CLIMBING BACK INTO THE LOWER 80S. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... AS OF 1253 PM EDT TUESDAY...CONVECTION IS QUICKLY DEVELOPING OVER THE PAST HOUR. AND JUST A FEW MINUTES AGO WE HAD THE FIRST LIGHTNING STROKE IN THE CELL NORTH OF PLATTSBURGH (WHICH BY THE WAY HAS A LITTLE BIT OF HAIL WELL ALOFT IN IT). LATEST LAPS MESOANALYSIS SHOWS 1500-2500 J/KG CAPE FOR MOST OF VERMONT, THANKS IN LARGE PART TO TEMPERATURES IN THE UPPER 70S TO LOWER 80S AND DEWPOINTS IN THE LOW/MID 60S. CAPE VALUES ARE LOWER ACROSS NORTHERN NEW YORK DUE TO THE EARLIER CLOUDINESS WHICH HAVE HELD BACK TEMPERATURES A LITTLE BIT. AS TYPICAL, THE FIRST CONVECTION HAS BEEN ALONG THE EASTERN SLOPES OF THE `DACKS. MOST OF THE 12Z/15Z RUNS OF MESO-SCALE MODELS SHOW THIS TO ONE EXTENT OR ANOTHER. THESE CELLS THEN DEVELOP AND PUSH EAST AS ADDITIONAL CONVECTION SHOULD FORM ALONG THE CENTRAL GREEN MOUNTAINS ABOUT 18Z. WESTERLY STEERING FLOW ALOFT SHOULD THEN MEAN THE BULK OF THE SHOWERS/STORMS ARE INTO EASTERN VERMONT AFTER 4-5PM. SURFACE FRONT STILL NOT QUITE TO THE ST LAWRENCE VALLEY, BUT IT WILL SLOWLY BE WORKING ITS WAY ACROSS NORTHERN NEW YORK DURING THE AFTERNOON. COULD SEE A FEW ADDITIONAL SCATTERED SHOWERS/ISOLATED T-STORMS FIRE AHEAD OF THAT. MESO-MODELS ALSO INDICATE THIS POSSIBILITY. SMALL HAIL STILL LOOKING LIKE THE MAIN ISSUE WITH ANY STRONGER T-STORMS THAT COULD DEVELOP. SO THE FORECAST UPDATE HAS BEEN PRIMARILY TO TRY TO BETTER TIME/LOCATE THE HIGHER LEVEL OF CONVECTIVE COVERAGE. RELIED ON A MIX OF BTV4, BTV6 AND HRRR MODELS. BASICALLY MAKES THE NORTHERN HALF OF VERMONT AS THE FOCUS OF CONVECTION. TWEAKED TEMPERATURES A BIT UP AS WELL, ESPECIALLY FOR VERMONT. BTV ALREADY REACHED 81F, SO PRIOR TO THE SHOWERS COMING INTO THE AREA, WE COULD RISE ANOTHER DEGREE OR TWO. OTHERWISE, WE`LL SEE HOW THIS AFTERNOON EVOLVES. NOT EVERYONE WILL SEE ANY SHOWERS/STORMS, BUT ENOUGH ON THE RADAR SCOPE TO KEEP IT INTERESTING. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... AS OF 314 AM EDT TUESDAY...THE WEAK COLD FRONTAL BOUNDARY SLIDES FAR ENOUGH SEWD INTO SOUTHERN NEW ENGLAND THAT OUR WEATHER SHOULD BE PRECIPITATION FREE ON WEDNESDAY. KEPT JUST A SLIGHT CHANCE OF A SHOWER (20 POP) ACROSS PORTIONS OF RUTLAND/WINDSOR COUNTIES...AND DRY ELSEWHERE. ALSO LOOKING AT SOME LOWER HUMIDITY BEING USHERED IN BEHIND THE FRONT...WITH SFC DEWPOINTS DROPPING INTO THE LOWER 50S. 850MB TEMPS OF +10C TO +11C SUPPORT AFTERNOON HIGHS IN THE MID-UPR 70S FOR MOST LOCATIONS. MOSTLY SUNNY SKIES AND LIGHT NW WINDS WILL MAKE FOR A PLEASANT DAY. GENERALLY TRANQUIL WEDNESDAY NIGHT...THOUGH WE/LL NEED TO WATCH A SHORTWAVE TROUGH MOVING SEWD FROM ONTARIO/SWRN QUEBEC THROUGH THE PARENT LONGWAVE TROUGH. THIS EMBEDDED FEATURE MAY REACH THE ST. LAWRENCE VALLEY DURING THE PRE-DAWN HOURS. SOME INDICATIONS IN 00Z GFS/NAM/BTV-4KM WRF THAT THIS SHORTWAVE TROUGH WILL BE ASSOCIATED WITH RAIN SHOWER ACTIVITY MOVING INTO THE ST. LAWRENCE VALLEY BETWEEN 09-12Z. OTHERWISE...LOOKING AT DRY AND MOSTLY CLEAR CONDITIONS ELSEWHERE. SHOULD SET UP A FAVORABLE CONDITIONS FOR RADIATIONAL FOG IN THE VALLEYS OF CENTRAL/ERN VT. LOWS WEDNESDAY NIGHT EXPECTED IN THE LOW-MID 50S...EXCEPT MID-UPR 40S IN THE ADIRONDACKS AND VERMONT`S NORTHEAST KINGDOM. PREVAILING CYCLONIC MID-TROPOSPHERIC FLOW AND PASSAGE OF EMBEDDED SHORTWAVE TROUGH AND THERMAL TROUGH DURING DAYTIME HEATING WILL RESULT IN DEVELOPMENT OF SCATTERED SHOWERS AND PERHAPS ISOLD TSTM ACTIVITY FOR THURSDAY AFTERNOON. WITH SFC DEWPOINTS ONLY IN THE 50S...CAPE VALUES WILL BE RATHER MODEST (AROUND 500-1000 J/KG AT BEST)...AND WITH ONLY 15-20 KTS OF NWLY DEEP-LAYER FLOW...NOT ANTICIPATING ANY SEVERE THREAT. IT APPEARS BASED ON PROJECTED TIMING THAT THE BEST FORCING WILL BE ACROSS VERMONT COINCIDENT WITH DAYTIME HEATING. THUS...HAVE PLACED THE HIGHEST POPS ACROSS VT AND THAT IS ALSO WHERE THE BEST POTENTIAL EXISTS FOR SURFACE- BASED THUNDERSTORM ACTIVITY. HIGHS GENERALLY IN THE LOW-MID 70S WITH INTERVALS OF PARTLY SUNNY CONDITIONS AWAY FROM SHOWERS AND TSTMS. NOT ANTICIPATING A WASHOUT...BUT THOSE WITH OUTDOOR PLANS SHOULD ANTICIPATE SOME SHOWER/THUNDERSTORM ACTIVITY AROUND WITH PERHAPS A BRIEF DOWNPOUR...ESPECIALLY FOR THE AFTERNOON HOURS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 333 AM EDT TUESDAY...THURSDAY NIGHT WILL SEE DECREASING SHOWERS AND STORMS AS THE COLD FRONT MOVES THROUGH THE REGION FROM WEST TO EAST. AN UPPER LEVEL WAVE EMBEDDED IN FLOW AROUND TROUGH WILL KEEP LINGERING SHOWERS ACROSS PORTIONS OF THE NORTHEAST KINGDOM ON FRIDAY. COVERAGE OF SHOWERS WILL BE LIMITED DUE TO DRYING NW FLOW DEVELOPING AS SFC HIGH PRESSURE BUILDS IN OVER SERN CANADA. 500 MB HT LEVEL INCREASES NOTICEABLY OVER THE WEEKEND...RESULTING IN DRY FORECAST. AS THE RIDGE CRESTS OVER THE REGION SATURDAY...S/SW FLOW WILL RETURN...FILTERING WARMER AIR. THIS WILL RESULT IN WARMING TREND...WITH MAX TEMPS FRIDAY AND SATURDAY RANGING FROM L60S TO L80S. TEMPERATURES INCREASE DURING THE WEEK WITH MAXES REACHING THE L80S IN THE VALLEYS. MIN TEMPERATURES WILL BE IN THE M50S IN THE MTNS AND U50S TO L60S IN THE VALLEYS. MONDAY MAY BE THE LAST COMPLETELY DRY DAY AS UPPER TROUGH APPROACHES FROM THE WEST. && .AVIATION /17Z TUESDAY THROUGH SUNDAY/... THROUGH 18Z WEDNESDAY...THOUGH PRIMARILY VFR...A MIX OF FLIGHT CATEGORIES ANTICIPATED THIS AFTN/EVENING WITH BRIEF MVFR TO IFR VISIBILITY IN SHOWERS/THUNDERSTORMS...MVFR CEILINGS AND POSSIBLE MIST DEVELOPMENT AT MSS AND SLK. REGIONAL RADAR SHOWS SCT SHOWERS/THUNDERSTORMS DEVELOPING AHEAD OF A COLD FRONT. INITIAL DEVELOPMENT IN THE CHAMPLAIN VALLEY AND EASTERN ADIRONDACKS...AND EXPECT AREAL COVERAGE TO INCREASE INTO THE AFTN/EVENING HRS. PRIMARY THREAT AREA FOR THUNDER AT PBG AND THE VT TAFS WITH ANY THUNDERSTORM CAPABLE OF DOWNPOURS...LOCAL TURBULENCE AND PERHAPS SOME SMALL HAIL. HAVE INDICATED VCTS FOR THESE TAFS UNDER THOSE EXPECTATIONS...WITH VCSH INDICATED AT SLK AND MSS WHERE AIRMASS IS A LITTLE MORE STABLE UNDER OVERCAST. WILL AMEND FOR LOWER VISIBILITY. COLD FRONT PUSHES SLOWLY SOUTH INTO THE OVERNIGHT...THOUGH BASED ON UPSTREAM OBS SKIES ARE NOT LIKELY TO FULLY CLEAR OUT EXCEPT AT SLK AND MSS THROUGH THE PRE-DAWN HOURS. FOR THAT REASON HAVE OPTED TO INTRODUCE SCT-BKN VFR/MVFR CEILINGS AND SHOW MIST AT MSS AND SLK. MORE SIGNIFICANT LIFTING OF CEILINGS AFTER 12Z. SOUTH WINDS AHEAD OF THE FRONT TO BECOME MORE VARIABLE AS FRONT APPROACHES...THEN TURNING NORTHERLY 4-6 KTS INTO WEDNESDAY. OUTLOOK 18Z WEDNESDAY THROUGH SATURDAY... 18Z WEDNESDAY THROUGH 12Z FRIDAY...PREDOMINANTLY VFR ALTHOUGH A CHANCE OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EACH AFTERNOON AND EVENING...ALONG WITH THE POTENTIAL FOR IFR/LIFR FOG/BR DEVELOPMENT EACH NIGHT...MAINLY MPV/SLK. 12Z FRIDAY ONWARD...VFR UNDER BUILDING HIGH PRESSURE...HOWEVER PERIODS OF IFR IN FOG/BR POSSIBLE AT NIGHT...AGAIN MAINLY MPV/SLK. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...BANACOS NEAR TERM...NASH SHORT TERM...BANACOS LONG TERM...KGM AVIATION...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
103 PM EDT TUE AUG 5 2014 .SYNOPSIS... A COLD FRONT SHIFTING SOUTHEASTWARD FROM ONTARIO AND QUEBEC WILL BRING WIDELY SCATTERED SHOWERS AND THUNDERSTORMS TO THE NORTH COUNTRY THIS AFTERNOON. A FEW STRONGER STORMS ARE POSSIBLE...WITH BRIEF HEAVY DOWNPOURS AND SMALL HAIL. THE FRONT CLEARS THE AREA TO THE SOUTH SETTING UP A PLEASANT DAY ON WEDNESDAY WITH LOWER HUMIDITY LEVELS AND HIGH TEMPERATURES MAINLY IN THE MID TO UPPER 70S. AN UPPER-LEVEL DISTURBANCE WILL BRING ADDITIONAL SHOWERS AND ISOLATED THUNDERSTORMS TO THE REGION FOR THURSDAY AFTERNOON. ACTIVITY WILL BE MOST WIDESPREAD ACROSS VERMONT. GENERALLY FAIR CONDITIONS ARE EXPECTED WITH HIGH PRESSURE ON FRIDAY AND THROUGH THE WEEKEND...WITH AFTERNOON TEMPERATURES CLIMBING BACK INTO THE LOWER 80S. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... AS OF 1253 PM EDT TUESDAY...CONVECTION IS QUICKLY DEVELOPING OVER THE PAST HOUR. AND JUST A FEW MINUTES AGO WE HAD THE FIRST LIGHTNING STROKE IN THE CELL NORTH OF PLATTSBURGH (WHICH BY THE WAY HAS A LITTLE BIT OF HAIL WELL ALOFT IN IT). LATEST LAPS MESOANALYSIS SHOWS 1500-2500 J/KG CAPE FOR MOST OF VERMONT, THANKS IN LARGE PART TO TEMPERATURES IN THE UPPER 70S TO LOWER 80S AND DEWPOINTS IN THE LOW/MID 60S. CAPE VALUES ARE LOWER ACROSS NORTHERN NEW YORK DUE TO THE EARLIER CLOUDINESS WHICH HAVE HELD BACK TEMPERATURES A LITTLE BIT. AS TYPICAL, THE FIRST CONVECTION HAS BEEN ALONG THE EASTERN SLOPES OF THE `DACKS. MOST OF THE 12Z/15Z RUNS OF MESO-SCALE MODELS SHOW THIS TO ONE EXTENT OR ANOTHER. THESE CELLS THEN DEVELOP AND PUSH EAST AS ADDITIONAL CONVECTION SHOULD FORM ALONG THE CENTRAL GREEN MOUNTAINS ABOUT 18Z. WESTERLY STEERING FLOW ALOFT SHOULD THEN MEAN THE BULK OF THE SHOWERS/STORMS ARE INTO EASTERN VERMONT AFTER 4-5PM. SURFACE FRONT STILL NOT QUITE TO THE ST LAWRENCE VALLEY, BUT IT WILL SLOWLY BE WORKING ITS WAY ACROSS NORTHERN NEW YORK DURING THE AFTERNOON. COULD SEE A FEW ADDITIONAL SCATTERED SHOWERS/ISOLATED T-STORMS FIRE AHEAD OF THAT. MESO-MODELS ALSO INDICATE THIS POSSIBILITY. SMALL HAIL STILL LOOKING LIKE THE MAIN ISSUE WITH ANY STRONGER T-STORMS THAT COULD DEVELOP. SO THE FORECAST UPDATE HAS BEEN PRIMARILY TO TRY TO BETTER TIME/LOCATE THE HIGHER LEVEL OF CONVECTIVE COVERAGE. RELIED ON A MIX OF BTV4, BTV6 AND HRRR MODELS. BASICALLY MAKES THE NORTHERN HALF OF VERMONT AS THE FOCUS OF CONVECTION. TWEAKED TEMPERATURES A BIT UP AS WELL, ESPECIALLY FOR VERMONT. BTV ALREADY REACHED 81F, SO PRIOR TO THE SHOWERS COMING INTO THE AREA, WE COULD RISE ANOTHER DEGREE OR TWO. OTHERWISE, WE`LL SEE HOW THIS AFTERNOON EVOLVES. NOT EVERYONE WILL SEE ANY SHOWERS/STORMS, BUT ENOUGH ON THE RADAR SCOPE TO KEEP IT INTERESTING. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... AS OF 314 AM EDT TUESDAY...THE WEAK COLD FRONTAL BOUNDARY SLIDES FAR ENOUGH SEWD INTO SOUTHERN NEW ENGLAND THAT OUR WEATHER SHOULD BE PRECIPITATION FREE ON WEDNESDAY. KEPT JUST A SLIGHT CHANCE OF A SHOWER (20 POP) ACROSS PORTIONS OF RUTLAND/WINDSOR COUNTIES...AND DRY ELSEWHERE. ALSO LOOKING AT SOME LOWER HUMIDITY BEING USHERED IN BEHIND THE FRONT...WITH SFC DEWPOINTS DROPPING INTO THE LOWER 50S. 850MB TEMPS OF +10C TO +11C SUPPORT AFTERNOON HIGHS IN THE MID-UPR 70S FOR MOST LOCATIONS. MOSTLY SUNNY SKIES AND LIGHT NW WINDS WILL MAKE FOR A PLEASANT DAY. GENERALLY TRANQUIL WEDNESDAY NIGHT...THOUGH WE/LL NEED TO WATCH A SHORTWAVE TROUGH MOVING SEWD FROM ONTARIO/SWRN QUEBEC THROUGH THE PARENT LONGWAVE TROUGH. THIS EMBEDDED FEATURE MAY REACH THE ST. LAWRENCE VALLEY DURING THE PRE-DAWN HOURS. SOME INDICATIONS IN 00Z GFS/NAM/BTV-4KM WRF THAT THIS SHORTWAVE TROUGH WILL BE ASSOCIATED WITH RAIN SHOWER ACTIVITY MOVING INTO THE ST. LAWRENCE VALLEY BETWEEN 09-12Z. OTHERWISE...LOOKING AT DRY AND MOSTLY CLEAR CONDITIONS ELSEWHERE. SHOULD SET UP A FAVORABLE CONDITIONS FOR RADIATIONAL FOG IN THE VALLEYS OF CENTRAL/ERN VT. LOWS WEDNESDAY NIGHT EXPECTED IN THE LOW-MID 50S...EXCEPT MID-UPR 40S IN THE ADIRONDACKS AND VERMONT`S NORTHEAST KINGDOM. PREVAILING CYCLONIC MID-TROPOSPHERIC FLOW AND PASSAGE OF EMBEDDED SHORTWAVE TROUGH AND THERMAL TROUGH DURING DAYTIME HEATING WILL RESULT IN DEVELOPMENT OF SCATTERED SHOWERS AND PERHAPS ISOLD TSTM ACTIVITY FOR THURSDAY AFTERNOON. WITH SFC DEWPOINTS ONLY IN THE 50S...CAPE VALUES WILL BE RATHER MODEST (AROUND 500-1000 J/KG AT BEST)...AND WITH ONLY 15-20 KTS OF NWLY DEEP-LAYER FLOW...NOT ANTICIPATING ANY SEVERE THREAT. IT APPEARS BASED ON PROJECTED TIMING THAT THE BEST FORCING WILL BE ACROSS VERMONT COINCIDENT WITH DAYTIME HEATING. THUS...HAVE PLACED THE HIGHEST POPS ACROSS VT AND THAT IS ALSO WHERE THE BEST POTENTIAL EXISTS FOR SURFACE- BASED THUNDERSTORM ACTIVITY. HIGHS GENERALLY IN THE LOW-MID 70S WITH INTERVALS OF PARTLY SUNNY CONDITIONS AWAY FROM SHOWERS AND TSTMS. NOT ANTICIPATING A WASHOUT...BUT THOSE WITH OUTDOOR PLANS SHOULD ANTICIPATE SOME SHOWER/THUNDERSTORM ACTIVITY AROUND WITH PERHAPS A BRIEF DOWNPOUR...ESPECIALLY FOR THE AFTERNOON HOURS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 333 AM EDT TUESDAY...THURSDAY NIGHT WILL SEE DECREASING SHOWERS AND STORMS AS THE COLD FRONT MOVES THROUGH THE REGION FROM WEST TO EAST. AN UPPER LEVEL WAVE EMBEDDED IN FLOW AROUND TROUGH WILL KEEP LINGERING SHOWERS ACROSS PORTIONS OF THE NORTHEAST KINGDOM ON FRIDAY. COVERAGE OF SHOWERS WILL BE LIMITED DUE TO DRYING NW FLOW DEVELOPING AS SFC HIGH PRESSURE BUILDS IN OVER SERN CANADA. 500 MB HT LEVEL INCREASES NOTICEABLY OVER THE WEEKEND...RESULTING IN DRY FORECAST. AS THE RIDGE CRESTS OVER THE REGION SATURDAY...S/SW FLOW WILL RETURN...FILTERING WARMER AIR. THIS WILL RESULT IN WARMING TREND...WITH MAX TEMPS FRIDAY AND SATURDAY RANGING FROM L60S TO L80S. TEMPERATURES INCREASE DURING THE WEEK WITH MAXES REACHING THE L80S IN THE VALLEYS. MIN TEMPERATURES WILL BE IN THE M50S IN THE MTNS AND U50S TO L60S IN THE VALLEYS. MONDAY MAY BE THE LAST COMPLETELY DRY DAY AS UPPER TROUGH APPROACHES FROM THE WEST. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THROUGH 12Z WEDNESDAY...MORNING IFR/LIFR FOG WILL DISSIPATE BY 14Z AT KMPV/KMSS AND KSLK. VFR LOW AND MID LEVEL CLOUDS WILL INCREASE FROM THE WEST AS A COLD FRONT APPROACHES THE REGION. SCATTERED SHOWERS AND A FEW THUNDERSTORMS ARE FORECAST TO DEVELOP GENERALLY FROM WEST TO EAST AS THE FRONT MAKES ITS WAY ACROSS THE REGION. THIS WILL RESULT IN A CHANCE FOR -SHRA AT KMSS STARTING BTWN 13Z-15Z...14Z-17Z AT KSLK AND THE CPV...17Z-20Z FOR KMPV AND KRUT. SCT SHOWERS AND PSBL STORMS WILL PERSIST INTO THE EARLY EVENING HOURS. ANY STORM WILL HAVE THE POTENTIAL FOR GUSTY WINDS...HEAVY DOWNPOURS AND SMALL HAIL...CREATING PERIODS OF MVFR/IFR. AS THE AFOREMENTIONED FRONT MOVES OVER THE NORTH COUNTRY...S/SW WINDS AT 5-10KTS WILL SHIFT MORE W/NW. BEHIND THE FRONT...WINDS WILL SUBSIDE TO 2-6KTS TUESDAY EVENING. CLOUDS WILL DISSIPATE...ALLOWING FOR PSBL BR/FG DEVELOPMENT...ESP AT KMPV AND KSLK. OUTLOOK 12Z WEDNESDAY THROUGH SATURDAY... 12Z WEDNESDAY THROUGH 12Z FRIDAY...PREDOMINANTLY VFR ALTHOUGH A CHANCE OF SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS EACH AFTERNOON AND EVENING...ALONG WITH THE POTENTIAL FOR IFR/LIFR FOG/BR DEVELOPMENT EACH NIGHT...MAINLY MPV/SLK. 12Z FRIDAY ONWARD...VFR UNDER BUILDING HIGH PRESSURE...HOWEVER PERIODS OF IFR IN FOG/BR POSSIBLE AT NIGHT...AGAIN MAINLY MPV/SLK. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...BANACOS NEAR TERM...NASH SHORT TERM...BANACOS LONG TERM...KGM AVIATION...KGM
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
650 PM EDT TUE AUG 5 2014 .SYNOPSIS... TROPICAL STORM BERTHA WILL LIFT OFF TO THE NORTHEAST TONIGHT AND WEDNESDAY. A COLD FRONT WILL DROP THROUGH THE AREA ON THURSDAY THEN REMAINED STALLED TO THE SOUTH THROUGH THE WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... AS OF 645 PM TUESDAY...WIDELY SCATTERED SHOWERS HAVE DEVELOPING OVER THE SOUND COUNTIES AND A FEW OF THESE SHOWERS ARE STARTING TO MAKE THEIR WAY TOWARD THE COAST. PRECIPITABLE WATER ACROSS THE CWA STILL RANGES FROM 1.6 TO 2 INCHES SO THESE SHOWERS WILL PUT DOWN A DECENT AMOUNT OF RAIN IN A SHORT PERIOD OF TIME. THE 3KM HRRR DOES A GOOD JOB AT DEPICTING THE BASIC LOCATION OF THESE SHOWERS AND ALONG WITH THE RAP AND NAM12...SHOWS ACTIVITY WANING WITH LOSS OF HEATING BY 02Z OR SO. REMAINDER OF THE NIGHT WILL BE WARM WITH PATCHY DENSE FOG...ESPECIALLY INLAND. LOWS WILL GENERALLY BE IN THE UPPER 60S/LOW 70S. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH 6 PM WEDNESDAY/... AS OF 3 PM TUE...BROAD UPPER TROUGH CONTINUES ACROSS THE AREA WED AND OVERALL QUIET DAY EXPECTED FOR ENC. WILL MAINTAIN SC POP FOR SEABREEZE ACTIVITY DURING THE AFTERNOON HOURS...THINKING ACTIVITY WILL BE FAIRLY ISOLATED. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS SUPPORT HIGHS IN THE MID 80S TO LOWER 90S. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... AS OF 300 PM TUESDAY...MODELS IN DECENT AGREEMENT MOST OF PERIOD WITH SERIES OF SHRT WVS MOVING THROUGH BROAD EASTERN TROF. INITIAL SHRT WV WILL PUSH A WEAK FRONT THROUGH AREA WED NIGHT AND THU WITH SCT CONVECTIVE ACTIVITY PSBL. BRIEF DRYING PERIOD WILL FOLLOW THU NIGHT AND FRIDAY WITH ONLY MINIMAL POPS. SOME MODEL DIFFERENCES IN DETAILS OVER WEEKEND...BUT GENERAL AGREEMENT ON PSBL WEAK DAMMING EVENT SAT-MON WITH SHRT WV ENERGY INDUCING SFC WV DEVELOPMENT ALONG STALLED FRONTAL BNDRY JUST S OF AREA WITH HIGH PRES EXTENDING INTO AREA FROM N. LEANED TO A WPC/GFS/ECMWF BLEND INDICATING HIGHEST POPS AROUND 50% SAT INTO SUN NIGHT...DECREASING TO CLIMO 20/30 POPS MON-TUE AS MAIN SFC WAVES MOVES OFFSHORE. TEMPS WILL BE NEAR NORMAL FOR WED NIGHT AND THU...THEN SEVERAL DEGS BELOW NORMAL REST OF PERIOD. HIGH TEMPS MAY NOT REACH 80 SOME AREAS OVER WEEKEND IF PCPN WITH DAMMING IS MORE WDSPRD. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM /THROUGH 18Z WEDNESDAY/... AS OF 645 PM TUESDAY...FOR THE FIRST TIME IN A FEW TIMES...VFR CONDITIONS BEING REPORTED AT ALL TAF SITES. THE PRECIPITATION WILL REMAIN EAST OF THE SITES THIS EVENING BEFORE DISSIPATING. CONFIDENCE IS HIGH IN WIDESPREAD MVFR/IFR FOG LATE TONIGHT WITH ENOUGH RESIDUAL GROUND MOISTURE...COUPLED WITH LIGHT WINDS. SURFACE CONDENSATION PRESSURE DEFICIT LOOKS TO BE THE MOST FAVORABLE AT KEWN AND WILL LOWER VSBYS TO ABOUT ONE MILE THERE WITH 2 MILES AT THE OTHER SITES FROM GENERALLY 09Z TO 12Z. VFR CONDITIONS SHOULD PREVAIL FOR MOST OF THE DAY WEDNESDAY. AS OF 200 PM TUESDAY... VFR CONDITIONS WILL EVENTUALLY PREVAIL AT ALL TAF SITES THROUGH THE AFTERNOON/EVENING HOURS AS FRONTAL BOUNDARY MOVES OFFSHORE. SOME RESIDUAL MVFR CEILINGS EXIST AT PGV/ISO AND SHOULD DISSIPATE QUICKLY WITH PEAK DAYTIME HEATING. A CHANCE FOR A SHOWER STILL EXISTS THROUGH ABOUT 00Z BUT POTENTIAL SHOULD DECREASE WITH LOSS OF DIURNAL HEATING. THROUGH THE OVERNIGHT...A MOIST BOUNDARY LAYER SHOULD DECOUPLE WITH CALM WINDS...SATURATED GROUND...AND GENERALLY CLEAR SKIES...HIGHLY CONFIDENT IN REDUCED MVFR/IFR VISIBILITIES BEGINNING AROUND 06Z. AFTER SUNRISE...DAYTIME HEATING WILL ALLOW LOW LEVELS TO MIX OUT AND RETURN TO VFR CONDITIONS. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 300 PM TUESDAY...PREVAILING VFR EXPECTED WED NIGHT THROUGH FRI NIGHT OUTSIDE OF ISOLD/SCT CONVECTIVE ACTIVITY. WDSPRD SUB-VFR PSBL SAT-SUN WITH DAMMING EVENT BUT CONFIDENCE ONLY MODERATE AT THIS TIME. && .MARINE... SHORT TERM /THROUGH WEDNESDAY/... AS OF 650 PM TUESDAY...WINDS GENERALLY N/NE AT 5 TO 10 KNOTS AND SHOULD BACK TO MORE NW TOWARD MORNING PER LATEST 3KM HRRR/NAM12 WIND FORECAST. SEAS CONTINUES IN THE 4-7 FOOT RANGE WITH 11-12 SECOND SWELLS FROM DISTANT HURRICANE BERTHA. SEAS WILL GRADUALLY SUBSIDE OVERNIGHT INTO WED AS BERTHA LIFTS NE...AND LONG PERIOD SWELL SUBSIDES. ONLY CHANGE TO FORECAST WAS TO EXTEND SCA A FEW HOURS FOR WATERS BASED ON LATEST WAVEWATCH AND NWPS GUIDANCE. BACKING WINDS WED...NW EARLY BECOMING S/SW DURING THE AFTERNOON. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 300 PM TUESDAY...SW WINDS WILL INCREASE TO 10-15 KT AHEAD OF COLD FRONT WED NIGHT INTO EARLY THU...THEN SHIFT TO NE THU NIGHT INTO FRI WITH HIGH PRESSURE BUILDING IN BEHIND FRONT. WINDS WILL GRADUALLY VEER AROUND TO E AND SE OVER WEEKEND WITH SPEEDS MAINLY 15 KT OR LESS AS SFC LOW PRES MOVES ACROSS STALLED FRONTAL BNDRY TO S. BLEND OF WW3..NWPS AND PREVIOUS FCST FOR SEAS DURING PERIOD. HEIGHTS HOLDING AROUND 3-4 FT WITH PRE AND POST FRONTAL FLOW INTO FRIDAY...THEN MAINLY 2-3 FT SAT-SUN. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 2 PM EDT WEDNESDAY FOR AMZ150-152- 154. SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR AMZ156-158. && $$ SYNOPSIS...CQD NEAR TERM...CTC SHORT TERM...CQD LONG TERM...JBM AVIATION...JBM/CTC MARINE...JBM/CTC/CQD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
209 PM EDT TUE AUG 5 2014 .SYNOPSIS... A STALLED FRONT ALONG THE COAST WILL MOVE OFFSHORE TODAY AS TROPICAL STORM BERTHA MOVES PASSES WELL OFFSHORE OF THE CAROLINA COAST. SWELLS FROM BERTHA WILL LEAD TO AN INCREASED RIP CURRENT RISK ALONG AREA BEACHES THE NEXT SEVERAL DAYS. WARM AND MUGGY WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH THE WEEKEND...LIKELY HOLDING TEMPERATURES DOWN A FEW DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AS OF 945 AM TUESDAY...LATEST RADAR TRENDS CONTINUE TO ILLUSTRATE BEST CHANCE FOR PCPN TO OCCUR ACROSS COASTAL COUNTIES. THE SMALL LOW LEVEL CIRCULATION OVER THE OFFSHORE WATERS SSE OF CAPE FEAR...WILL CONTINUE TO PULL SLOWLY NE...AWAY FROM THE MAINLAND THIS AFTERNOON AND TONIGHT...TAKING THE PCPN WITH IT. ACROSS THE INLAND COUNTIES...DRIER AIR BEGINNING TO OVERSPREAD THIS AREA VIA LATEST WATER VAPOR IMAGERY TRENDS...ALONG WITH WEAK SUBSIDENCE BECOMING MORE WIDESPREAD. A FEW POPCORN TYPE DIURNALLY DRIVEN SHRA/TSRA STILL REMAINS POSSIBLE DURING THIS AFTERNOON/EARLY EVENING. OVERALL...WILL CONTINUE WITH THE DECREASING POP TREND THRU THIS AFTN AND EVENING. MAY NEED TO RE-VISIT AND INCREASE MAX TEMPS FOR AREAS ALONG AND WEST OF THE I-95 CORRIDOR AT THE NEXT UPDATE DUE TO ADDITIONAL INSOLATION REACHING THE SFC THEN PREVIOUSLY THOUGHT. PREVIOUS DISCUSSION................................. AS OF 645 AM TUESDAY...RADAR REVEALS A GROWING AREA OF RAIN WITH EMBEDDED CONVECTIVE ELEMENTS 30-100 MILES SOUTH AND SOUTHEAST OF CAPE FEAR...BUT A LONG RADAR LOOP REVEALS THE MAJORITY OF THE FORECAST AREA MAY BE TOO FAR WEST TO GET IN ON THIS PRECIPITATION. THE EXCEPTION IS GOING TO BE THE COASTAL CAPE FEAR REGION WHERE I HAVE NUDGED POPS UP TO AS HIGH AS 80 PERCENT IN THE SOUTHPORT-BALD HEAD ISLAND AREA. A WELL-DEFINED CIRCULATION IN RADAR IMAGERY ABOUT 60 MILES SOUTH OF OAK ISLAND APPEARS TO BE THE WESTERN ANCHOR POINT FOR THIS RAINFALL...AND DETERMINING THE PATH OF THIS FEATURE IS INSTRUMENTAL TO MAKING AN ACCURATE RAINFALL FORECAST. THE HRRR MAKES AN ATTEMPT TO INITIALIZE THE CIRCULATION AND ADVECTS IT NORTHEASTWARD...PASSING APPROXIMATELY 20 MILES EAST OF CAPE FEAR BETWEEN 16-17Z. ON THIS PATH THE BULK OF THE RAIN WILL REMAIN OVER THE OCEAN WITH THE WETTEST WEATHER EXPECTED ON LAND BETWEEN NOW AND NOON. OTHER THAN CHANGES TO SKY COVER AND POPS/PRECIP AMOUNT...THE ONLY OTHER SIGNIFICANT CHANGE WITH THE FORECAST WAS TO INCREASE THE COVERAGE OF FOG ACROSS THE INTERSTATE 95 CORRIDOR. VISIBILITIES HAVE GONE AS LOW AS 1/4 MILE IN SPOTS ALTHOUGH PREVAILING VISIBILITIES ARE HIGHER ACROSS THE REGION. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED ADDRESSING THE FOG. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... WE ARE JUST ABOUT TO GET RID OF THE DREARY WEATHER PATTERN THAT HAS BROUGHT UNSEASONABLY COOL...CLOUDY AND RAINY WEATHER TO THE COASTAL CAROLINAS FOR THE ENTIRE MONTH SO FAR. SO FAR AUGUST 2014 HAS SEEN THE 7TH COOLEST TEMPERATURES EVEN OBSERVED IN WILMINGTON WITH AN AVERAGE TEMPERATURE OF ONLY 75.7 DEGREES. HURRICANE BERTHA IS PASSING WELL EAST OF THE CAROLINAS WITH NO DIRECT IMPACTS ON OUR WEATHER TODAY. THE OLD STALLED FRONT APPEARS TO LIE ALONG THE BEACHES OF PENDER AND NEW HANOVER COUNTIES... EXTENDING SOUTHWARD FROM SOUTHPORT TO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. THIS FEATURE SHOULD BE DRAWN EASTWARD BEHIND BERTHA TODAY...WITH DRIER AIR GRADUALLY BUILDING IN FROM THE NORTH WITH TIME. RADAR SHOWS PLENTY OF SHOWERS ACROSS THE COASTAL WATERS. THESE ARE SHALLOW CONVECTIVE FEATURES WITH ECHO TOPS GENERALLY 20KFT OR LESS...EXCEPT FOR A FEW T-STORMS FARTHER OFFSHORE WITH TOPS OVER 30KFT. SINCE THE BULK OF THIS ACTIVITY IS SHALLOW IT IS BEING STEERED BY THE 700-850 MB MEAN FLOW WHICH IS CURRENTLY FROM THE EAST. THE 00Z GFS AND 06Z RUC (OUR PREFERRED MODELS TODAY) SHOW THIS STEERING FLOW BACKING MORE NORTHERLY WITH TIME WHICH SHOULD TEND TO LIMIT HOW FAR INLAND ANY SHOWER ACTIVITY WILL MOVE. FORECAST POPS RANGE FROM 30-50 PERCENT ALONG THE COAST THIS MORNING...DIMINISHING TO 20-30 PERCENT BY NOON. FOR INTERIOR SECTIONS OF THE EASTERN CAROLINAS UNLESS AN ISOLATED SHOWER CAN DEVELOP DURING THE AFTERNOON DRY WEATHER IS EXPECTED. HIGHS SHOULD RANGE FROM THE UPPER 80S TO NEAR 90 ACROSS THE SC PEE DEE REGION TO THE MID 80S AT THE COAST. FOR TONIGHT DRY AIR SHOULD FLOOD IN THROUGHOUT THE TROPOSPHERE WITH PRECIPITABLE WATER VALUES FALLING TO LESS THAN 1.5 INCHES. SKIES SHOULD BECOME MAINLY CLEAR BY EARLY EVENING AND THERE IS LITTLE POTENTIAL FOR FOG OR LOW STRATUS OVERNIGHT. LOWS SHOULD TO NEAR 70. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM TUESDAY...SUMMER RETURNS ON WEDNESDAY AS THE MID LEVEL FLOW GOES WESTERLY AND DOWNSLOPE ALLOWING FOR A PARTLY SUNNY AFTERNOON. PIEDMONT TROUGH DEVELOPS BUT IT ALONG WITH THE SEA BREEZE WILL GENERALLY BE TOO MOISTURE-DEPRIVED TO LEAD TO MEANINGFUL PRECIP CHANCES. AFTERNOON TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE CLIMO. PIEDMONT TROUGH PUSHES TOWARDS THE COAST ON THURSDAY WHILE A MID LEVEL SHORTWAVE PASSES OVERHEAD LATE IN THE AFTERNOON. NORMALLY THIS WOULD BE A GOOD SETUP FOR THUNDERSTORMS. HOWEVER THERE IS STILL VERY LITTLE MOISTURE ESPECIALLY THROUGH THE MID LEVELS. CONVECTION WILL BE LIMITED AND GENERALLY BE CONFINED TO THE COASTAL REGIONS. TEMPERATURES WILL BE QUITE SIMILAR TO THOSE OF WEDNESDAY. A COLD FRONT WILL ENTER THE REGION LATE THURSDAY NIGHT AND WILL KEEP ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 3 AM TUESDAY...HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THURSDAY NIGHT COLD FRONT TO END THE BRIEF SHORT TERM PERIODS SUMMER TEMPS. MOISTURE MAY POOL ALONG THE FRONT AND BRING SOME SLIGHT RAIN CHANCES OVER SWRN ZONES. THIS WILL HOLD TRUE INTO SATURDAY AS THE FRONT WASHES BACK CLOSER TO THE AREA...THE LOW RAIN CHANCES MAY INCREASE IN AREA WHILE AFTERNOON HIGHS REMAIN CAPPED BELOW CLIMO. SUNDAY IS WHEN RAIN CHANCES SHOULD RETURN AREA-WIDE AS THE FRONT LIFTS BACK INTO THE REGION. WAVE MOVES BY LATE SUNDAY INTO SUNDAY NIGHT POSSIBLY FURTHER RAMPING UP RAIN CHANCES...AND THEN LEAVING THE BOUNDARY IN OUR PRESENCE SANS WAVE ON MONDAY. CYCLONIC AND NWRLY MID LEVEL FLOW CONTINUES ON TUESDAY WITH SURFACE TROUGHINESS REDEVELOPING. RAIN CHANCES WILL LINGER INTO TUESDAY WITH CLIMO OR HIGHER CHANCES WHILE TEMPS REMAIN NEAR OR JUST SHY OF CLIMO. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 18Z...VFR CONDITIONS THRUOUT EXCEPT OVERNIGHT WHEN MVFR AND/OR IFR CONDITIONS POSSIBLY COULD OCCUR FROM REDUCED HORIZONTAL VSBY FROM FOG. WILL KEEP VCNTY SHRA/TSRA THIS AFTERNOON/EARLY EVENING...HOWEVER SUBSIDENCE ALOFT WILL HELP KEEP THE POPCORN TYPE CONVECTION FROM DEVELOPING ANY FURTHER IN THE VERTICAL. THUS...WILL CONTINUE WITH VCSH OR VCTS WHERE APPROPRIATE UNTIL SUNSET. FOR TONIGHT...WINDS BECOME CALM FOLLOWED BY A CHANCE FOR MVFR/IF FOG AFTER 05Z. STAYED WITH BR ALL TERMINALS BUT NEXT UPDATE WILL NEED TO FOCUS FOR POSSIBLE LIFR FROM DENSE FOG. FOR WEDNESDAY...SCT TO BKN CU CLOUD DECK POSSIBLE BY LATE MORNING. ANY FOG SHOULD DISSIPATE BY 13Z AT THE LATEST. EXTENDED OUTLOOK...ISOLATED SHOWERS WEDNESDAY AND THURSDAY. SCATTERED SHOWERS FRIDAY WITH SHOWERS LIKELY ON SATURDAY AND SUNDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 945 AM TUESDAY...SMALL CRAFT ADVISORY RAISED FOR THE ILM NC WATERS...DUE TO SEAS. SMALL CRAFT EXERCISE CAUTION DUE TO SEAS FOR THE ILM SC WATERS. BOTH WILL EXPIRE AT 900 PM THIS EVENING. BERTHA SWELLS NOW AFFECTING THE AREA WATERS...AND RUNNING HIGHER ACROSS THE ILM NC WATERS FROM CAPE FEAR NORTHWARD COMPARED TO THE REMAINING WATERS FROM SOUTH OF CAPE FEAR TO SOUTH SANTEE RIVER. FOR THE ILM NC WATERS...LATEST 41110 BUOY REPORTING SIGNIFICANT SEAS UP TO 5 FT...AND THE OFFSHORE BUOY 41036 REPORTING 8+ FT. BOTH BUOYS INDICATE SIG. SEAS PREDOMINATELY FROM BERTHA SWELL. PERIODS RANGE FROM 11 TO 14 SECONDS. FOR THE ILM SC WATERS...LATEST EDISTO BUOY REPORTED UP TO 7 FT SIG. SEAS...WITH WIND DRIVEN WAVES A BETTER CONTRIBUTING THEN WHATS OCCURRING ACROSS THE ILM NC WATERS. FOR WINDS...THE PROGGED SFC PRESSURE PATTERN AND GRADIENT AFTER THE DEPARTING LOW LEVEL CIRCULATION CURRENTLY MOVING FURTHER OFFSHORE FROM CAPE FEAR...WILL YIELD N TO NE WINDS AT 10-15 KT THIS AFTERNOON...BACKING TO NW TO NNW AT 10 KT DURING TONIGHT. PREVIOUS DISCUSSION................................... AS OF 645 AM TUESDAY...A CYCLONIC CIRCULATION IN RADAR IMAGERY LOCATED ABOUT 60 MILES SOUTH OF OAK ISLAND IS THE FEATURE TO WATCH THIS MORNING. THE LATEST HRRR MODEL SEEMS TO HAVE INITIALIZED THIS SWIRL AND MOVES IT SLOWLY NORTHEASTWARD...MISSING THE TIP OF CAPE FEAR ABOUT 20 MILES TO THE EAST BETWEEN NOON AND 1 PM EDT. LACK OF MARINE OBSERVATIONS WEST OF THE LOW IS HINDERING ANALYSIS...BUT NOAA BUOY 41004 EAST OF CHARLESTON HAS NOT GUSTED ANY HIGHER THAN 17 KNOTS IN THE PAST FEW HOURS. WAVE HEIGHTS AT THE LOCAL BUOYS HAVE CHANGED LITTLE FROM 3 AM AND NO CHANGES ARE NEEDED THERE. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... AN OLD STALLED FRONT RUNS ALONG THE BEACHES OF SE NORTH CAROLINA SOUTHWARD INTO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. HURRICANE BERTHA IS WELL EAST OF THE CAROLINAS AND WILL MOVE NORTHEASTWARD AND FARTHER AWAY TODAY. THE GEORGIA LOW AND OUR FRONT SHOULD BE DRAWN OFFSHORE TOWARD BERTHA...LEADING TO A DRYING TREND DEVELOPING WITH TIME. UNTIL THEN...WAVES OF SHOWERS AND EMBEDDED T-STORMS ACROSS THE COASTAL WATERS SHOULD CONTINUE THROUGH THE MORNING HOURS. GENERALLY EAST OR NORTHEAST WINDS WILL TURN NORTHERLY THIS EVENING...THEN WESTERLY OVERNIGHT AS BERTHA PULLS THE LOW AND FRONT AWAY FROM THE AREA. THIS WILL LET DRIER AIR FLOOD INTO THE AREA. A SIGNIFICANT SWELL FROM BERTHA WILL IMPACT THE WATERS TODAY AND SHOULD BE THE LARGEST CONTRIBUTING FACTOR IN SEA HEIGHT FORECASTS TODAY. SEAS OF 4-5 FEET ARE EXPECTED...DIMINISHING TO 3-4 FT LATE TONIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...PIEDMONT TROUGH ON WEDNESDAY WILL BACK INITIALLY WEST FLOW TO SOUTHWEST OR EVEN SOUTH WHILE ADDING A FEW KNOTS TO AVERAGE SPEED. SEAS MAINLY COMPRISED OF WIND WAVES IN THE 2 TO 3 FT RANGE. AS THE BOUNDARY MOVES TOWARDS THE COAST ON THURSDAY THE WIND WILL DIMINISH LATER IN THE DAY AS THE GRADIENT IS PUSHED OUT TO SEA BY THE TROUGH. THE BOUNDARY WILL SINK SOUTH ACROSS THE ZONES RATHER SLOWLY LATE THURSDAY NIGHT BRINGING A TURN TO NORTHERLY WINDS FOLLOWED BY ADDITIONAL VEERING TO EASTERLY BY THE PERIODS END...AT LEAST FOR NORTHERN ZONES. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...POST-FRONTAL ONSHORE FLOW ON FRIDAY WILL BE IN THE 10 TO 15 KT RANGE EARLY BUT SETTLE BY ABOUT 5 KT. SEAS WILL BE RUNNING JUST 2-3 FEET THEN MOST AREAS. THE HIGH WILL CONTINUE WEDGING IN FROM POINTS NORTH INTO SATURDAY WHILE THE FRONT STALLED TO THE SOUTH TRIES TO MOVE BACK TO THE NORTH SLIGHTLY. WITH RELATIVELY UNCHANGED WINDS AND NO SWELL ENERGY TO SPEAK OF SEAS WILL REMAIN 2 FEET AGAIN ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR SCZ054- 056. NC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ106- 108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR AMZ250- 252. && $$ SYNOPSIS...MBB NEAR TERM...DCH/TRA SHORT TERM...MBB LONG TERM...MBB AVIATION...DCH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1043 AM EDT TUE AUG 5 2014 .SYNOPSIS... A STALLED FRONT ALONG THE COAST WILL MOVE OFFSHORE TODAY AS TROPICAL STORM BERTHA MOVES PASSES WELL OFFSHORE OF THE CAROLINA COAST. SWELLS FROM BERTHA WILL LEAD TO AN INCREASED RIP CURRENT RISK ALONG AREA BEACHES THE NEXT SEVERAL DAYS. WARM AND MUGGY WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH THE WEEKEND...LIKELY HOLDING TEMPERATURES DOWN A FEW DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AS OF 945 AM TUESDAY...LATEST RADAR TRENDS CONTINUE TO ILLUSTRATE BEST CHANCE FOR PCPN TO OCCUR ACROSS COASTAL COUNTIES. THE SMALL LOW LEVEL CIRCULATION OVER THE OFFSHORE WATERS SSE OF CAPE FEAR...WILL CONTINUE TO PULL SLOWLY NE...AWAY FROM THE MAINLAND THIS AFTERNOON AND TONIGHT...TAKING THE PCPN WITH IT. ACROSS THE INLAND COUNTIES...DRIER AIR BEGINNING TO OVERSPREAD THIS AREA VIA LATEST WATER VAPOR IMAGERY TRENDS...ALONG WITH WEAK SUBSIDENCE BECOMING MORE WIDESPREAD. A FEW POPCORN TYPE DIURNALLY DRIVEN SHRA/TSRA STILL REMAINS POSSIBLE DURING THIS AFTERNOON/EARLY EVENING. OVERALL...WILL CONTINUE WITH THE DECREASING POP TREND THRU THIS AFTN AND EVENING. MAY NEED TO RE-VISIT AND INCREASE MAX TEMPS FOR AREAS ALONG AND WEST OF THE I-95 CORRIDOR AT THE NEXT UPDATE DUE TO ADDITIONAL INSOLATION REACHING THE SFC THEN PREVIOUSLY THOUGHT. PREVIOUS DISCUSSION............................................ AS OF 645 AM TUESDAY...RADAR REVEALS A GROWING AREA OF RAIN WITH EMBEDDED CONVECTIVE ELEMENTS 30-100 MILES SOUTH AND SOUTHEAST OF CAPE FEAR...BUT A LONG RADAR LOOP REVEALS THE MAJORITY OF THE FORECAST AREA MAY BE TOO FAR WEST TO GET IN ON THIS PRECIPITATION. THE EXCEPTION IS GOING TO BE THE COASTAL CAPE FEAR REGION WHERE I HAVE NUDGED POPS UP TO AS HIGH AS 80 PERCENT IN THE SOUTHPORT-BALD HEAD ISLAND AREA. A WELL-DEFINED CIRCULATION IN RADAR IMAGERY ABOUT 60 MILES SOUTH OF OAK ISLAND APPEARS TO BE THE WESTERN ANCHOR POINT FOR THIS RAINFALL...AND DETERMINING THE PATH OF THIS FEATURE IS INSTRUMENTAL TO MAKING AN ACCURATE RAINFALL FORECAST. THE HRRR MAKES AN ATTEMPT TO INITIALIZE THE CIRCULATION AND ADVECTS IT NORTHEASTWARD...PASSING APPROXIMATELY 20 MILES EAST OF CAPE FEAR BETWEEN 16-17Z. ON THIS PATH THE BULK OF THE RAIN WILL REMAIN OVER THE OCEAN WITH THE WETTEST WEATHER EXPECTED ON LAND BETWEEN NOW AND NOON. OTHER THAN CHANGES TO SKY COVER AND POPS/PRECIP AMOUNT...THE ONLY OTHER SIGNIFICANT CHANGE WITH THE FORECAST WAS TO INCREASE THE COVERAGE OF FOG ACROSS THE INTERSTATE 95 CORRIDOR. VISIBILITIES HAVE GONE AS LOW AS 1/4 MILE IN SPOTS ALTHOUGH PREVAILING VISIBILITIES ARE HIGHER ACROSS THE REGION. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED ADDRESSING THE FOG. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... WE ARE JUST ABOUT TO GET RID OF THE DREARY WEATHER PATTERN THAT HAS BROUGHT UNSEASONABLY COOL...CLOUDY AND RAINY WEATHER TO THE COASTAL CAROLINAS FOR THE ENTIRE MONTH SO FAR. SO FAR AUGUST 2014 HAS SEEN THE 7TH COOLEST TEMPERATURES EVEN OBSERVED IN WILMINGTON WITH AN AVERAGE TEMPERATURE OF ONLY 75.7 DEGREES. HURRICANE BERTHA IS PASSING WELL EAST OF THE CAROLINAS WITH NO DIRECT IMPACTS ON OUR WEATHER TODAY. THE OLD STALLED FRONT APPEARS TO LIE ALONG THE BEACHES OF PENDER AND NEW HANOVER COUNTIES... EXTENDING SOUTHWARD FROM SOUTHPORT TO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. THIS FEATURE SHOULD BE DRAWN EASTWARD BEHIND BERTHA TODAY...WITH DRIER AIR GRADUALLY BUILDING IN FROM THE NORTH WITH TIME. RADAR SHOWS PLENTY OF SHOWERS ACROSS THE COASTAL WATERS. THESE ARE SHALLOW CONVECTIVE FEATURES WITH ECHO TOPS GENERALLY 20KFT OR LESS...EXCEPT FOR A FEW T-STORMS FARTHER OFFSHORE WITH TOPS OVER 30KFT. SINCE THE BULK OF THIS ACTIVITY IS SHALLOW IT IS BEING STEERED BY THE 700-850 MB MEAN FLOW WHICH IS CURRENTLY FROM THE EAST. THE 00Z GFS AND 06Z RUC (OUR PREFERRED MODELS TODAY) SHOW THIS STEERING FLOW BACKING MORE NORTHERLY WITH TIME WHICH SHOULD TEND TO LIMIT HOW FAR INLAND ANY SHOWER ACTIVITY WILL MOVE. FORECAST POPS RANGE FROM 30-50 PERCENT ALONG THE COAST THIS MORNING...DIMINISHING TO 20-30 PERCENT BY NOON. FOR INTERIOR SECTIONS OF THE EASTERN CAROLINAS UNLESS AN ISOLATED SHOWER CAN DEVELOP DURING THE AFTERNOON DRY WEATHER IS EXPECTED. HIGHS SHOULD RANGE FROM THE UPPER 80S TO NEAR 90 ACROSS THE SC PEE DEE REGION TO THE MID 80S AT THE COAST. FOR TONIGHT DRY AIR SHOULD FLOOD IN THROUGHOUT THE TROPOSPHERE WITH PRECIPITABLE WATER VALUES FALLING TO LESS THAN 1.5 INCHES. SKIES SHOULD BECOME MAINLY CLEAR BY EARLY EVENING AND THERE IS LITTLE POTENTIAL FOR FOG OR LOW STRATUS OVERNIGHT. LOWS SHOULD TO NEAR 70. && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 AM TUESDAY...SUMMER RETURNS ON WEDNESDAY AS THE MID LEVEL FLOW GOES WESTERLY AND DOWNSLOPE ALLOWING FOR A PARTLY SUNNY AFTERNOON. PIEDMONT TROUGH DEVELOPS BUT IT ALONG WITH THE SEA BREEZE WILL GENERALLY BE TOO MOISTURE-DEPRIVED TO LEAD TO MEANINGFUL PRECIP CHANCES. AFTERNOON TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE CLIMO. PIEDMONT TROUGH PUSHES TOWARDS THE COAST ON THURSDAY WHILE A MID LEVEL SHORTWAVE PASSES OVERHEAD LATE IN THE AFTERNOON. NORMALLY THIS WOULD BE A GOOD SETUP FOR THUNDERSTORMS. HOWEVER THERE IS STILL VERY LITTLE MOISTURE ESPECIALLY THROUGH THE MID LEVELS. CONVECTION WILL BE LIMITED AND GENERALLY BE CONFINED TO THE COASTAL REGIONS. TEMPERATURES WILL BE QUITE SIMILAR TO THOSE OF WEDNESDAY. A COLD FRONT WILL ENTER THE REGION LATE THURSDAY NIGHT AND WILL KEEP ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 3 AM TUESDAY...HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THURSDAY NIGHT COLD FRONT TO END THE BRIEF SHORT TERM PERIODS SUMMER TEMPS. MOISTURE MAY POOL ALONG THE FRONT AND BRING SOME SLIGHT RAIN CHANCES OVER SWRN ZONES. THIS WILL HOLD TRUE INTO SATURDAY AS THE FRONT WASHES BACK CLOSER TO THE AREA...THE LOW RAIN CHANCES MAY INCREASE IN AREA WHILE AFTERNOON HIGHS REMAIN CAPPED BELOW CLIMO. SUNDAY IS WHEN RAIN CHANCES SHOULD RETURN AREA-WIDE AS THE FRONT LIFTS BACK INTO THE REGION. WAVE MOVES BY LATE SUNDAY INTO SUNDAY NIGHT POSSIBLY FURTHER RAMPING UP RAIN CHANCES...AND THEN LEAVING THE BOUNDARY IN OUR PRESENCE SANS WAVE ON MONDAY. CYCLONIC AND NWRLY MID LEVEL FLOW CONTINUES ON TUESDAY WITH SURFACE TROUGHINESS REDEVELOPING. RAIN CHANCES WILL LINGER INTO TUESDAY WITH CLIMO OR HIGHER CHANCES WHILE TEMPS REMAIN NEAR OR JUST SHY OF CLIMO. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...QUITE A BIT OF LIFR CONDITIONS AROUND THE CWA...WHICH WILL LIKELY PERSIST FOR TWO OR THREE HOURS. SOME LIGHT SHOWERS NEAR THE COAST...NOT ASSOCIATED WITH TROPICAL STORM BERTHA. NOT LOOKING FOR THAT MUCH CONVECTION TODAY...MAYBE ILM. LOW PRESSURE OFF THE SOUTH CAROLINA COAST WILL FLING SOME LIGHT MOISTURE ONSHORE TO NORTH CAROLINA. THE LOW WILL PULL NORTHEAST THIS AFTERNOON...TAKING ITS MOISTURE WITH IT. SOME LOW LEVEL MOISTURE WILL REMAIN TONIGHT...HOWEVER MUCH LESS FOG/STRATUS THAN THIS MORNING. EXTENDED OUTLOOK...ISOLATED SHOWERS WED. SCATTERED SHOWERS LATE THURSDAY WITH A BETTER CHANCE FOR CONVECTION FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 945 AM TUESDAY...SMALL CRAFT ADVISORY RAISED FOR THE ILM NC WATERS...DUE TO SEAS. SMALL CRAFT EXERCISE CAUTION DUE TO SEAS FOR THE ILM SC WATERS. BOTH WILL EXPIRE AT 900 PM THIS EVENING. BERTHA SWELLS NOW AFFECTING THE AREA WATERS...AND RUNNING HIGHER ACROSS THE ILM NC WATERS FROM CAPE FEAR NORTHWARD COMPARED TO THE REMAINING WATERS FROM SOUTH OF CAPE FEAR TO SOUTH SANTEE RIVER. FOR THE ILM NC WATERS...LATEST 41110 BUOY REPORTING SIGNIFICANT SEAS UP TO 5 FT...AND THE OFFSHORE BUOY 41036 REPORTING 8+ FT. BOTH BUOYS INDICATE SIG. SEAS PREDOMINATELY FROM BERTHA SWELL. PERIODS RANGE FROM 11 TO 14 SECONDS. FOR THE ILM SC WATERS...LATEST EDISTO BUOY REPORTED UP TO 7 FT SIG. SEAS...WITH WIND DRIVEN WAVES A BETTER CONTRIBUTING THEN WHATS OCCURRING ACROSS THE ILM NC WATERS. FOR WINDS...THE PROGGED SFC PRESSURE PATTERN AND GRADIENT AFTER THE DEPARTING LOW LEVEL CIRCULATION CURRENTLY MOVING FURTHER OFFSHORE FROM CAPE FEAR...WILL YIELD N TO NE WINDS AT 10-15 KT THIS AFTERNOON...BACKING TO NW TO NNW AT 10 KT DURING TONIGHT. PREVIOUS DISCUSSION.............................................. AS OF 645 AM TUESDAY...A CYCLONIC CIRCULATION IN RADAR IMAGERY LOCATED ABOUT 60 MILES SOUTH OF OAK ISLAND IS THE FEATURE TO WATCH THIS MORNING. THE LATEST HRRR MODEL SEEMS TO HAVE INITIALIZED THIS SWIRL AND MOVES IT SLOWLY NORTHEASTWARD...MISSING THE TIP OF CAPE FEAR ABOUT 20 MILES TO THE EAST BETWEEN NOON AND 1 PM EDT. LACK OF MARINE OBSERVATIONS WEST OF THE LOW IS HINDERING ANALYSIS...BUT NOAA BUOY 41004 EAST OF CHARLESTON HAS NOT GUSTED ANY HIGHER THAN 17 KNOTS IN THE PAST FEW HOURS. WAVE HEIGHTS AT THE LOCAL BUOYS HAVE CHANGED LITTLE FROM 3 AM AND NO CHANGES ARE NEEDED THERE. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... AN OLD STALLED FRONT RUNS ALONG THE BEACHES OF SE NORTH CAROLINA SOUTHWARD INTO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. HURRICANE BERTHA IS WELL EAST OF THE CAROLINAS AND WILL MOVE NORTHEASTWARD AND FARTHER AWAY TODAY. THE GEORGIA LOW AND OUR FRONT SHOULD BE DRAWN OFFSHORE TOWARD BERTHA...LEADING TO A DRYING TREND DEVELOPING WITH TIME. UNTIL THEN...WAVES OF SHOWERS AND EMBEDDED T-STORMS ACROSS THE COASTAL WATERS SHOULD CONTINUE THROUGH THE MORNING HOURS. GENERALLY EAST OR NORTHEAST WINDS WILL TURN NORTHERLY THIS EVENING...THEN WESTERLY OVERNIGHT AS BERTHA PULLS THE LOW AND FRONT AWAY FROM THE AREA. THIS WILL LET DRIER AIR FLOOD INTO THE AREA. A SIGNIFICANT SWELL FROM BERTHA WILL IMPACT THE WATERS TODAY AND SHOULD BE THE LARGEST CONTRIBUTING FACTOR IN SEA HEIGHT FORECASTS TODAY. SEAS OF 4-5 FEET ARE EXPECTED...DIMINISHING TO 3-4 FT LATE TONIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...PIEDMONT TROUGH ON WEDNESDAY WILL BACK INITIALLY WEST FLOW TO SOUTHWEST OR EVEN SOUTH WHILE ADDING A FEW KNOTS TO AVERAGE SPEED. SEAS MAINLY COMPRISED OF WIND WAVES IN THE 2 TO 3 FT RANGE. AS THE BOUNDARY MOVES TOWARDS THE COAST ON THURSDAY THE WIND WILL DIMINISH LATER IN THE DAY AS THE GRADIENT IS PUSHED OUT TO SEA BY THE TROUGH. THE BOUNDARY WILL SINK SOUTH ACROSS THE ZONES RATHER SLOWLY LATE THURSDAY NIGHT BRINGING A TURN TO NORTHERLY WINDS FOLLOWED BY ADDITIONAL VEERING TO EASTERLY BY THE PERIODS END...AT LEAST FOR NORTHERN ZONES. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...POST-FRONTAL ONSHORE FLOW ON FRIDAY WILL BE IN THE 10 TO 15 KT RANGE EARLY BUT SETTLE BY ABOUT 5 KT. SEAS WILL BE RUNNING JUST 2-3 FEET THEN MOST AREAS. THE HIGH WILL CONTINUE WEDGING IN FROM POINTS NORTH INTO SATURDAY WHILE THE FRONT STALLED TO THE SOUTH TRIES TO MOVE BACK TO THE NORTH SLIGHTLY. WITH RELATIVELY UNCHANGED WINDS AND NO SWELL ENERGY TO SPEAK OF SEAS WILL REMAIN 2 FEET AGAIN ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR SCZ054- 056. NC...HIGH RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR NCZ106- 108-110. MARINE...SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR AMZ250- 252. && $$ SYNOPSIS...MBB NEAR TERM...DCH/TRA SHORT TERM...MBB LONG TERM...MBB AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
653 AM EDT TUE AUG 5 2014 .SYNOPSIS... A STALLED FRONT ALONG THE COAST WILL MOVE OFFSHORE TODAY AS TROPICAL STORM BERTHA MOVES PASSES WELL OFFSHORE OF THE CAROLINA COAST. SWELLS FROM BERTHA WILL LEAD TO AN INCREASED RIP CURRENT RISK ALONG AREA BEACHES THE NEXT SEVERAL DAYS. WARM AND MUGGY WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH THE WEEKEND...LIKELY HOLDING TEMPERATURES DOWN A FEW DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AS OF 645 AM TUESDAY...RADAR REVEALS A GROWING AREA OF RAIN WITH EMBEDDED CONVECTIVE ELEMENTS 30-100 MILES SOUTH AND SOUTHEAST OF CAPE FEAR...BUT A LONG RADAR LOOP REVEALS THE MAJORITY OF THE FORECAST AREA MAY BE TOO FAR WEST TO GET IN ON THIS PRECIPITATION. THE EXCEPTION IS GOING TO BE THE COASTAL CAPE FEAR REGION WHERE I HAVE NUDGED POPS UP TO AS HIGH AS 80 PERCENT IN THE SOUTHPORT-BALD HEAD ISLAND AREA. A WELL-DEFINED CIRCULATION IN RADAR IMAGERY ABOUT 60 MILES SOUTH OF OAK ISLAND APPEARS TO BE THE WESTERN ANCHOR POINT FOR THIS RAINFALL...AND DETERMINING THE PATH OF THIS FEATURE IS INSTRUMENTAL TO MAKING AN ACCURATE RAINFALL FORECAST. THE HRRR MAKES AN ATTEMPT TO INITIALIZE THE CIRCULATION AND ADVECTS IT NORTHEASTWARD...PASSING APPROXIMATELY 20 MILES EAST OF CAPE FEAR BETWEEN 16-17Z. ON THIS PATH THE BULK OF THE RAIN WILL REMAIN OVER THE OCEAN WITH THE WETTEST WEATHER EXPECTED ON LAND BETWEEN NOW AND NOON. OTHER THAN CHANGES TO SKY COVER AND POPS/PRECIP AMOUNT...THE ONLY OTHER SIGNIFICANT CHANGE WITH THE FORECAST WAS TO INCREASE THE COVERAGE OF FOG ACROSS THE INTERSTATE 95 CORRIDOR. VISIBILITIES HAVE GONE AS LOW AS 1/4 MILE IN SPOTS ALTHOUGH PREVAILING VISIBILITIES ARE HIGHER ACROSS THE REGION. A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED ADDRESSING THE FOG. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... WE ARE JUST ABOUT TO GET RID OF THE DREARY WEATHER PATTERN THAT HAS BROUGHT UNSEASONABLY COOL...CLOUDY AND RAINY WEATHER TO THE COASTAL CAROLINAS FOR THE ENTIRE MONTH SO FAR. SO FAR AUGUST 2014 HAS SEEN THE 7TH COOLEST TEMPERATURES EVEN OBSERVED IN WILMINGTON WITH AN AVERAGE TEMPERATURE OF ONLY 75.7 DEGREES. HURRICANE BERTHA IS PASSING WELL EAST OF THE CAROLINAS WITH NO DIRECT IMPACTS ON OUR WEATHER TODAY. THE OLD STALLED FRONT APPEARS TO LIE ALONG THE BEACHES OF PENDER AND NEW HANOVER COUNTIES... EXTENDING SOUTHWARD FROM SOUTHPORT TO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. THIS FEATURE SHOULD BE DRAWN EASTWARD BEHIND BERTHA TODAY...WITH DRIER AIR GRADUALLY BUILDING IN FROM THE NORTH WITH TIME. RADAR SHOWS PLENTY OF SHOWERS ACROSS THE COASTAL WATERS. THESE ARE SHALLOW CONVECTIVE FEATURES WITH ECHO TOPS GENERALLY 20KFT OR LESS...EXCEPT FOR A FEW T-STORMS FARTHER OFFSHORE WITH TOPS OVER 30KFT. SINCE THE BULK OF THIS ACTIVITY IS SHALLOW IT IS BEING STEERED BY THE 700-850 MB MEAN FLOW WHICH IS CURRENTLY FROM THE EAST. THE 00Z GFS AND 06Z RUC (OUR PREFERRED MODELS TODAY) SHOW THIS STEERING FLOW BACKING MORE NORTHERLY WITH TIME WHICH SHOULD TEND TO LIMIT HOW FAR INLAND ANY SHOWER ACTIVITY WILL MOVE. FORECAST POPS RANGE FROM 30-50 PERCENT ALONG THE COAST THIS MORNING...DIMINISHING TO 20-30 PERCENT BY NOON. FOR INTERIOR SECTIONS OF THE EASTERN CAROLINAS UNLESS AN ISOLATED SHOWER CAN DEVELOP DURING THE AFTERNOON DRY WEATHER IS EXPECTED. HIGHS SHOULD RANGE FROM THE UPPER 80S TO NEAR 90 ACROSS THE SC PEE DEE REGION TO THE MID 80S AT THE COAST. FOR TONIGHT DRY AIR SHOULD FLOOD IN THROUGHOUT THE TROPOSPHERE WITH PRECIPITABLE WATER VALUES FALLING TO LESS THAN 1.5 INCHES. SKIES SHOULD BECOME MAINLY CLEAR BY EARLY EVENING AND THERE IS LITTLE POTENTIAL FOR FOG OR LOW STRATUS OVERNIGHT. LOWS SHOULD TO NEAR 70. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...SUMMER RETURNS ON WEDNESDAY AS THE MID LEVEL FLOW GOES WESTERLY AND DOWNSLOPE ALLOWING FOR A PARTLY SUNNY AFTERNOON. PIEDMONT TROUGH DEVELOPS BUT IT ALONG WITH THE SEA BREEZE WILL GENERALLY BE TOO MOISTURE-DEPRIVED TO LEAD TO MEANINGFUL PRECIP CHANCES. AFTERNOON TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE CLIMO. PIEDMONT TROUGH PUSHES TOWARDS THE COAST ON THURSDAY WHILE A MID LEVEL SHORTWAVE PASSES OVERHEAD LATE IN THE AFTERNOON. NORMALLY THIS WOULD BE A GOOD SETUP FOR THUNDERSTORMS. HOWEVER THERE IS STILL VERY LITTLE MOISTURE ESPECIALLY THROUGH THE MID LEVELS. CONVECTION WILL BE LIMITED AND GENERALLY BE CONFINED TO THE COASTAL REGIONS. TEMPERATURES WILL BE QUITE SIMILAR TO THOSE OF WEDNESDAY. A COLD FRONT WILL ENTER THE REGION LATE THURSDAY NIGHT AND WILL KEEP ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 AM TUESDAY...HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THURSDAY NIGHT COLD FRONT TO END THE BRIEF SHORT TERM PERIODS SUMMER TEMPS. MOISTURE MAY POOL ALONG THE FRONT AND BRING SOME SLIGHT RAIN CHANCES OVER SWRN ZONES. THIS WILL HOLD TRUE INTO SATURDAY AS THE FRONT WASHES BACK CLOSER TO THE AREA...THE LOW RAIN CHANCES MAY INCREASE IN AREA WHILE AFTERNOON HIGHS REMAIN CAPPED BELOW CLIMO. SUNDAY IS WHEN RAIN CHANCES SHOULD RETURN AREA-WIDE AS THE FRONT LIFTS BACK INTO THE REGION. WAVE MOVES BY LATE SUNDAY INTO SUNDAY NIGHT POSSIBLY FURTHER RAMPING UP RAIN CHANCES...AND THEN LEAVING THE BOUNDARY IN OUR PRESENCE SANS WAVE ON MONDAY. CYCLONIC AND NWRLY MID LEVEL FLOW CONTINUES ON TUESDAY WITH SURFACE TROUGHINESS REDEVELOPING. RAIN CHANCES WILL LINGER INTO TUESDAY WITH CLIMO OR HIGHER CHANCES WHILE TEMPS REMAIN NEAR OR JUST SHY OF CLIMO. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...QUITE A BIT OF LIFR CONDITIONS AROUND THE CWA...WHICH WILL LIKELY PERSIST FOR TWO OR THREE HOURS. SOME LIGHT SHOWERS NEAR THE COAST...NOT ASSOCIATED WITH TROPICAL STORM BERTHA. NOT LOOKING FOR THAT MUCH CONVECTION TODAY...MAYBE ILM. LOW PRESSURE OFF THE SOUTH CAROLINA COAST WILL FLING SOME LIGHT MOISTURE ONSHORE TO NORTH CAROLINA. THE LOW WILL PULL NORTHEAST THIS AFTERNOON...TAKING ITS MOISTURE WITH IT. SOME LOW LEVEL MOISTURE WILL REMAIN TONIGHT...HOWEVER MUCH LESS FOG/STRATUS THAN THIS MORNING. EXTENDED OUTLOOK...ISOLATED SHOWERS WED. SCATTERED SHOWERS LATE THURSDAY WITH A BETTER CHANCE FOR CONVECTION FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 645 AM TUESDAY...A CYCLONIC CIRCULATION IN RADAR IMAGERY LOCATED ABOUT 60 MILES SOUTH OF OAK ISLAND IS THE FEATURE TO WATCH THIS MORNING. THE LATEST HRRR MODEL SEEMS TO HAVE INITIALIZED THIS SWIRL AND MOVES IT SLOWLY NORTHEASTWARD...MISSING THE TIP OF CAPE FEAR ABOUT 20 MILES TO THE EAST BETWEEN NOON AND 1 PM EDT. LACK OF MARINE OBSERVATIONS WEST OF THE LOW IS HINDERING ANALYSIS...BUT NOAA BUOY 41004 EAST OF CHARLESTON HAS NOT GUSTED ANY HIGHER THAN 17 KNOTS IN THE PAST FEW HOURS. WAVE HEIGHTS AT THE LOCAL BUOYS HAVE CHANGED LITTLE FROM 3 AM AND NO CHANGES ARE NEEDED THERE. PREVIOUS DISCUSSION FROM 300 AM FOLLOWS... AN OLD STALLED FRONT RUNS ALONG THE BEACHES OF SE NORTH CAROLINA SOUTHWARD INTO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. HURRICANE BERTHA IS WELL EAST OF THE CAROLINAS AND WILL MOVE NORTHEASTWARD AND FARTHER AWAY TODAY. THE GEORGIA LOW AND OUR FRONT SHOULD BE DRAWN OFFSHORE TOWARD BERTHA...LEADING TO A DRYING TREND DEVELOPING WITH TIME. UNTIL THEN...WAVES OF SHOWERS AND EMBEDDED T-STORMS ACROSS THE COASTAL WATERS SHOULD CONTINUE THROUGH THE MORNING HOURS. GENERALLY EAST OR NORTHEAST WINDS WILL TURN NORTHERLY THIS EVENING...THEN WESTERLY OVERNIGHT AS BERTHA PULLS THE LOW AND FRONT AWAY FROM THE AREA. THIS WILL LET DRIER AIR FLOOD INTO THE AREA. A SIGNIFICANT SWELL FROM BERTHA WILL IMPACT THE WATERS TODAY AND SHOULD BE THE LARGEST CONTRIBUTING FACTOR IN SEA HEIGHT FORECASTS TODAY. SEAS OF 4-5 FEET ARE EXPECTED...DIMINISHING TO 3-4 FT LATE TONIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...PIEDMONT TROUGH ON WEDNESDAY WILL BACK INITIALLY WEST FLOW TO SOUTHWEST OR EVEN SOUTH WHILE ADDING A FEW KNOTS TO AVERAGE SPEED. SEAS MAINLY COMPRISED OF WIND WAVES IN THE 2 TO 3 FT RANGE. AS THE BOUNDARY MOVES TOWARDS THE COAST ON THURSDAY THE WIND WILL DIMINISH LATER IN THE DAY AS THE GRADIENT IS PUSHED OUT TO SEA BY THE TROUGH. THE BOUNDARY WILL SINK SOUTH ACROSS THE ZONES RATHER SLOWLY LATE THURSDAY NIGHT BRINGING A TURN TO NORTHERLY WINDS FOLLOWED BY ADDITIONAL VEERING TO EASTERLY BY THE PERIODS END...AT LEAST FOR NORTHERN ZONES. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...POST-FRONTAL ONSHORE FLOW ON FRIDAY WILL BE IN THE 10 TO 15 KT RANGE EARLY BUT SETTLE BY ABOUT 5 KT. SEAS WILL BE RUNNING JUST 2-3 FEET THEN MOST AREAS. THE HIGH WILL CONTINUE WEDGING IN FROM POINTS NORTH INTO SATURDAY WHILE THE FRONT STALLED TO THE SOUTH TRIES TO MOVE BACK TO THE NORTH SLIGHTLY. WITH RELATIVELY UNCHANGED WINDS AND NO SWELL ENERGY TO SPEAK OF SEAS WILL REMAIN 2 FEET AGAIN ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...TRA SHORT TERM...MBB LONG TERM...MBB AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
646 AM EDT TUE AUG 5 2014 .SYNOPSIS...LOW PRESSURE MOVES NORTHEAST JUST OFF OF THE CAROLINA COAST TODAY THROUGH THIS EVENING. WEAK HIGH PRESSURE WILL BE LOCATED OVER THE APPALACHIANS. A COLD FRONT MOVES SOUTH OVER THE REGION WEDNESDAY AFTERNOON INTO THURSDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 305 AM TUESDAY... WITH LOW PRESSURE OFF OF THE CAROLINA COAST...THE LATEST IR FOG SATELLITE IMAGE SHOWED THE WESTERN EDGE OF A SHIELD OF MID- AND HIGH- LEVEL CLOUDS MAINLY ALONG AND EAST OF ABOUT U.S. 1...WITH PATCHY CIRRUS TOWARD THE TRIAD. UNDERNEATH THE HIGHER CLOUDS OBSERVATIONS SHOWED SOME LOW CLOUDS HAD FORMED...AND IT WAS NEAR THE WESTERN EDGE OF THE HIGHER CLOUDS THAT VISIBILITIES WERE LOWEST...PARTICULARLY TOWARD KHNZ AND FOR A TIME NEAR KTTA. AS NOTED IN THE AVIATION DISCUSSION BELOW...THE HRRR WRF EARLY THIS MORNING HAS BEEN CONSISTENT IN DEVELOPING THE LOWER-VISIBILITY FOG MAINLY FROM THE TRIANGLE NORTHEAST...WHICH SEEMS REASONABLE GIVEN THE ORIENTATION OF THE CLOUD SHIELD ALOFT AND THE LIGHT NORTHEAST LOW-LEVEL FLOW. THE GRIDDED FORECAST WILL NOTE AREAS OF FOG AND PATCHY DRIZZLE MAINLY FROM THE TRIANGLE NORTH AND NORTHEAST...WITH A SLIGHT CHANCE OF SHOWERS EARLY THIS MORNING ALONG AND EAST OF INTERSTATE 95 IN THE DEEPER MOISTURE CLOSER TO THE COASTAL LOW PRESSURE. WHILE THE RAP AND HRRR WRF ARE DRY IN CENTRAL NORTH CAROLINA TODAY...THE NAM HAS COPIOUS PRECIPITATION OVER A QUARTER-INCH IN A LARGE PART OF THE COASTAL PLAIN TODAY. LEANED WITH THIS FORECAST MORE TOWARD THE DRIER GUIDANCE...AS DRIER MID-LEVEL AIR WAS SLOWLY MOVING EAST INTO THE WESTERN PART OF THE STATE ON THE LATEST WATER VAPOR IMAGERY...AND ONLY WEAK LIFT FORECAST. GFS BUFR SOUNDINGS ARE STABLE...AND MEAN LAYER RELATIVE HUMIDITY IS FORECAST TO DECREASE GRADUALLY DURING THE DAY ON BOTH THE NAM AND GFS AS PRECIPITABLE WATER VALUES ALSO SLOWLY FALL. IT SHOULD BE NOTED THAT WITH THE BETTER MID-LEVEL WINDS MOVING THROUGH EARLY THIS MORNING...THERE HAVE BEEN A COUPLE OF SHOWERS THAT HAVE DEVELOPED VERY BRIEFLY OVER UPSTATE SOUTH CAROLINA. WILL CERTAINLY MONITOR RADAR TRENDS...BUT FOR NOW THE FORECAST WILL ONLY SHOW A SLIGHT CHANCE OF A SHOWER ALONG AND EAST OF ABOUT U.S. 1 WITH A CHANCE OF A SHOWER OR THUNDERSTORM FROM INTERSTATE 95 EAST. 1000- 850MB THICKNESSES SUPPORT HIGHS IN THE UPPER 80S...AND WHEN MORNING CLOUDS ARE CONSIDERED...WILL FORECAST HIGHS IN THE MID TO UPPER 80S UNDER A NORTH-TO-NORTHEAST WIND 10 MPH OR LESS. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AS OF 305 AM TUESDAY... BUFR SOUNDINGS ARE STABLE OVERNIGHT ON BOTH THE NAM AND THE GFS...WITH THE GFS IN PARTICULAR SHOWING A SMALL VOLUME OF MID-LEVEL MOISTURE AS THE TROUGH AXIS ALOFT MOVES THROUGH AND A WEAK MID-LEVEL SHORTWAVE FOLLOWS THE TROUGH AXIS OVERNIGHT IN THE NORTHWEST FLOW. THIS SHOULD TRANSLATE INTO A PERIOD OF SCATTERED MID-LEVEL CLOUDS... POSSIBLY BROKEN FOR A PERIOD IF THE GFS VERIFIES. LOW-LEVEL MOISTURE REMAINS BEST TOWARD INTERSTATE 95 AND MAY NOTE PATCHY FOG POSSIBLE IN THE GRIDDED AND WORDED FORECASTS FOR THOSE AREAS LATE TONIGHT INTO VERY EARLY WEDNESDAY. OVERNIGHT LOWS 65 TO 70. WEDNESDAY AND WEDNESDAY NIGHT...GFS BUFR SOUNDINGS ARE STABLE WEDNESDAY...WHILE THE NAM SHOWS MODEST INSTABILITY PARTICULARLY TOWARD KRWI AND KFAY. ALTHOUGH THE GFS POPS ARE LOW THROUGHOUT CENTRAL NORTH CAROLINA...ITS QPF DOES NOTE A MINOR HUNDREDTH OR SO TOWARD THE COASTAL PLAIN WEDNESDAY AFTERNOON. SURFACE DEW POINTS SHOULD GENERALLY MIX WELL BASED ON THE BUFR SOUNDINGS AND A DEVELOPING WESTERLY SURFACE FLOW...MIXING LAST TOWARD THE COASTAL PLAIN WHERE THE COMBINATION OF JUST ENOUGH INSTABILITY...WEAK 850MB CONVERGENCE AND GRADUALLY LOWERING DEW POINTS COULD RESULT IN A VERY ISOLATED SHOWER OR STORM. THE MEAN AIR MASS STARTS TO MOISTEN WEDNESDAY NIGHT WITH THE APPROACH OF THE SURFACE FRONT...BUT WITH ONLY WEAK MID-LEVEL SUPPORT AND JET DYNAMICS NORTH OF THE AREA IN VIRGINIA...WILL LEAN TOWARD THE GFS AS OPPOSED TO THE WET NAM AND SHOW A DRY OVERNIGHT WEDNESDAY WITH AN EXPECTED INCREASE IN MID- LEVEL CLOUDS OVER MUCH OF THE AREA. 1000-850MB THICKNESSES SUPPORT HIGHS OF A BLEND OF MAV AND MET MOS GUIDANCE...OR 90 TO 95. OVERNIGHT LOWS WEDNESDAY NIGHT WITHIN A DEGREE OR THREE OF 70. -DJF THU/THU NIGHT: AN UPPER LEVEL TROUGH OVER NEW ENGLAND WILL LIFT INTO THE CANADIAN MARITIMES THU/THU NIGHT...WITH A WEAKENED WNW FLOW ALOFT OVER THE CAROLINAS. SUBSIDENCE IN THE WAKE OF THE TROUGH WILL RESULT IN SFC PRESSURE RISES OVER THE OH VALLEY AND MID ATLANTIC...WITH AN ATTENDANT SFC RIDGE AXIS /BACKDOOR COLD FRONT/ EXTENDING SOUTHWARD THROUGH VA TOWARD THE NC BORDER LATE THU. UNCERTAINTY PERSISTS W/REGARD TO THE TIMING/PROGRESS OF THE BACK DOOR COLD FRONT...LENDING A FAIR AMOUNT OF UNCERTAINTY TO TEMPERATURES...ESP ALONG AND NORTH OF HWY 64. AT THIS TIME WILL INDICATE HIGHS RANGING FROM ~90F SOUTH TO 83-85F NEAR THE VA BORDER. DESTABILIZATION/FORCING WILL HIGHLY DEPEND ON BOTH THE EVOLUTION OF THE FRONT AND OF SMALL AMPLITUDE DISTURBANCES IN WNW FLOW ALOFT... WITH CONSIDERABLE UNCERTAINTY IN PRECIP CHANCES/COVERAGE. AT THIS TIME WILL INDICATE A SLIGHT CHANCE DURING THE LATE AFTERNOON/EVENING HOURS. -VINCENT && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 AM TUESDAY... THE 00Z GFS/ECMWF ARE IN RELATIVELY GOOD AGREEMENT ON THE SYNOPTIC PATTERN FRI-MON. DESPITE GOOD SYNOPTIC AGREEMENT...SIGNIFICANT DISAGREEMENT ON MESOSCALE FEATURES AND CONVECTIVE EVOLUTION THROUGHOUT THE LONG TERM PERIOD LENDS ABOVE NORMAL UNCERTAINTY WITH REGARD TO PRECISE DETAILS (I.E. PRECIP AMOUNTS AND TIMING) FOR THE CAROLINAS. NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS FRI/SAT... DOWNSTREAM OF AN UPPER LEVEL RIDGE CENTERED OVER THE CENTRAL PLAINS/LOWER MIDWEST. THE UPPER LEVEL RIDGE IS PROGGED TO AMPLIFY AND RETROGRADE INTO THE ROCKIES ON SUN/MON...RESULTING IN A MORE AMPLIFIED PATTERN OF NNW FLOW ALOFT DOWNSTREAM OVER THE CAROLINAS. GIVEN AN ACTIVE UPPER LEVEL PATTERN JUXTAPOSED WITH MID-SUMMER MOISTURE...EXPECT ABOVE NORMAL CHANCES FOR PRECIPITATION AND BELOW NORMAL TEMPERATURES...PARTICULARLY SAT/SUN. -VINCENT && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 645 AM TUESDAY... AREAS OF IFR CONDITIONS IN FOG AND LOW CLOUDS WILL CONTINUE OVER MOST OF CENTRAL NORTH CAROLINA DURING THE EARLY MORNING. THE LATEST SATELLITE IMAGES SHOWED SOME LOWER CLOUDS SCATTERED AROUND THE TRIAD...WITH A SHIELD OF HIGHER CLOUDS NOTED OVER THE REST OF CENTRAL NORTH CAROLINA. FOG HAD DEVELOPED...WITH A NARROW BAND OF THE LOWEST VISIBILITY FROM KRDU NORTHEAST. THIS IS WHERE THE HRRR WRF MODEL SHOWED THE BEST POTENTIAL FOR SOLID IFR FOG POTENTIAL ORIGINATING OVER SOUTHERN VIRGINIA WHERE THERE WERE FEWER MID- AND HIGH-LEVEL CLOUDS EARLIER...THEN MOVING SOUTH-SOUTHWEST IN THE LIGHT LOW-LEVEL FLOW. AS LOW PRESSURE MOVES NORTHEAST OFF OF THE CAROLINA COAST THERE IS AN OUTSIDE CHANCE OF A SHOWER MAINLY ALONG AND EAST OF INTERSTATE 95...BUT THE CHANCES SEEM TOO LOW TO INCLUDE IN A TAF POINT FORECAST. VFR CONDITIONS SHOULD PREVAIL OVER CENTRAL NORTH CAROLINA BY AFTERNOON UNDER A NORTHEAST WIND. EVENING WINDS...LIGHT AND VARIABLE...MAY SHOW A TENDENCY TO BECOME LIGHT SOUTHERLY BY 06Z WEDNESDAY. PATCHY FOG AND SUB-VFR CONDITIONS ARE POSSIBLE LATE TONIGHT INTO EARLY WEDNESDAY...WITH THE BETTER CHANCES OF SUCH TOWARD KFAY AND KRWI WHERE THE LOW-LEVEL MOISTURE WILL BE HIGHER OVERNIGHT. BEYOND THE 12Z VALID TAF PERIOD...VFR CONDITIONS ARE ANTICIPATED FOR MUCH OF WEDNESDAY INTO WEDNESDAY NIGHT. BEHIND A COLD FRONT WHICH SETTLES JUST SOUTH OF THE AREA BY LATE THURSDAY...CHANCES FOR PRECIPITATION WILL INCREASE. INTO SATURDAY...THE HIGHER CHANCES AS THEY DEVELOP ARE EXPECTED TO BE OVER THE SOUTHWEST PIEDMONT INTO THE SANDHILLS. STILL...AREAS OF SUB-VFR CONDITIONS IN LOWER CLOUDS ARE POSSIBLE THROUGHOUT MUCH OF CENTRAL NORTH CAROLINA DEVELOPING SATURDAY OR ESPECIALLY SATURDAY NIGHT. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...DJF/VINCENT LONG TERM...VINCENT AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
640 AM EDT TUE AUG 5 2014 .SYNOPSIS... A STALLED FRONT ALONG THE COAST WILL MOVE OFFSHORE TODAY AS HURRICANE BERTHA MOVES PASSES WELL OFFSHORE OF THE CAROLINA COAST. SWELLS FROM BERTHA WILL LEAD TO AN INCREASED RIP CURRENT RISK ALONG AREA BEACHES THE NEXT SEVERAL DAYS. WARM AND MUGGY WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH THE WEEKEND...LIKELY HOLDING TEMPERATURES DOWN A FEW DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM TUESDAY...WE ARE JUST ABOUT TO GET RID OF THE DREARY WEATHER PATTERN THAT HAS BROUGHT UNSEASONABLY COOL...CLOUDY AND RAINY WEATHER TO THE COASTAL CAROLINAS FOR THE ENTIRE MONTH SO FAR. SO FAR AUGUST 2014 HAS SEEN THE 7TH COOLEST TEMPERATURES EVEN OBSERVED IN WILMINGTON WITH AN AVERAGE TEMPERATURE OF ONLY 75.7 DEGREES. HURRICANE BERTHA IS PASSING WELL EAST OF THE CAROLINAS WITH NO DIRECT IMPACTS ON OUR WEATHER TODAY. THE OLD STALLED FRONT APPEARS TO LIE ALONG THE BEACHES OF PENDER AND NEW HANOVER COUNTIES... EXTENDING SOUTHWARD FROM SOUTHPORT TO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. THIS FEATURE SHOULD BE DRAWN EASTWARD BEHIND BERTHA TODAY...WITH DRIER AIR GRADUALLY BUILDING IN FROM THE NORTH WITH TIME. RADAR SHOWS PLENTY OF SHOWERS ACROSS THE COASTAL WATERS. THESE ARE SHALLOW CONVECTIVE FEATURES WITH ECHO TOPS GENERALLY 20KFT OR LESS...EXCEPT FOR A FEW T-STORMS FARTHER OFFSHORE WITH TOPS OVER 30KFT. SINCE THE BULK OF THIS ACTIVITY IS SHALLOW IT IS BEING STEERED BY THE 700-850 MB MEAN FLOW WHICH IS CURRENTLY FROM THE EAST. THE 00Z GFS AND 06Z RUC (OUR PREFERRED MODELS TODAY) SHOW THIS STEERING FLOW BACKING MORE NORTHERLY WITH TIME WHICH SHOULD TEND TO LIMIT HOW FAR INLAND ANY SHOWER ACTIVITY WILL MOVE. FORECAST POPS RANGE FROM 30-50 PERCENT ALONG THE COAST THIS MORNING...DIMINISHING TO 20-30 PERCENT BY NOON. FOR INTERIOR SECTIONS OF THE EASTERN CAROLINAS UNLESS AN ISOLATED SHOWER CAN DEVELOP DURING THE AFTERNOON DRY WEATHER IS EXPECTED. HIGHS SHOULD RANGE FROM THE UPPER 80S TO NEAR 90 ACROSS THE SC PEE DEE REGION TO THE MID 80S AT THE COAST. FOR TONIGHT DRY AIR SHOULD FLOOD IN THROUGHOUT THE TROPOSPHERE WITH PRECIPITABLE WATER VALUES FALLING TO LESS THAN 1.5 INCHES. SKIES SHOULD BECOME MAINLY CLEAR BY EARLY EVENING AND THERE IS LITTLE POTENTIAL FOR FOG OR LOW STRATUS OVERNIGHT. LOWS SHOULD TO NEAR 70. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...SUMMER RETURNS ON WEDNESDAY AS THE MID LEVEL FLOW GOES WESTERLY AND DOWNSLOPE ALLOWING FOR A PARTLY SUNNY AFTERNOON. PIEDMONT TROUGH DEVELOPS BUT IT ALONG WITH THE SEA BREEZE WILL GENERALLY BE TOO MOISTURE-DEPRIVED TO LEAD TO MEANINGFUL PRECIP CHANCES. AFTERNOON TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE CLIMO. PIEDMONT TROUGH PUSHES TOWARDS THE COAST ON THURSDAY WHILE A MID LEVEL SHORTWAVE PASSES OVERHEAD LATE IN THE AFTERNOON. NORMALLY THIS WOULD BE A GOOD SETUP FOR THUNDERSTORMS. HOWEVER THERE IS STILL VERY LITTLE MOISTURE ESPECIALLY THROUGH THE MID LEVELS. CONVECTION WILL BE LIMITED AND GENERALLY BE CONFINED TO THE COASTAL REGIONS. TEMPERATURES WILL BE QUITE SIMILAR TO THOSE OF WEDNESDAY. A COLD FRONT WILL ENTER THE REGION LATE THURSDAY NIGHT AND WILL KEEP ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 AM TUESDAY...HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THURSDAY NIGHT COLD FRONT TO END THE BRIEF SHORT TERM PERIODS SUMMER TEMPS. MOISTURE MAY POOL ALONG THE FRONT AND BRING SOME SLIGHT RAIN CHANCES OVER SWRN ZONES. THIS WILL HOLD TRUE INTO SATURDAY AS THE FRONT WASHES BACK CLOSER TO THE AREA...THE LOW RAIN CHANCES MAY INCREASE IN AREA WHILE AFTERNOON HIGHS REMAIN CAPPED BELOW CLIMO. SUNDAY IS WHEN RAIN CHANCES SHOULD RETURN AREA-WIDE AS THE FRONT LIFTS BACK INTO THE REGION. WAVE MOVES BY LATE SUNDAY INTO SUNDAY NIGHT POSSIBLY FURTHER RAMPING UP RAIN CHANCES...AND THEN LEAVING THE BOUNDARY IN OUR PRESENCE SANS WAVE ON MONDAY. CYCLONIC AND NWRLY MID LEVEL FLOW CONTINUES ON TUESDAY WITH SURFACE TROUGHINESS REDEVELOPING. RAIN CHANCES WILL LINGER INTO TUESDAY WITH CLIMO OR HIGHER CHANCES WHILE TEMPS REMAIN NEAR OR JUST SHY OF CLIMO. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 12Z...QUITE A BIT OF LIFR CONDITIONS AROUND THE CWA...WHICH WILL LIKELY PERSIST FOR TWO OR THREE HOURS. SOME LIGHT SHOWERS NEAR THE COAST...NOT ASSOCIATED WITH TROPICAL STORM BERTHA. NOT LOOKING FOR THAT MUCH CONVECTION TODAY...MAYBE ILM. LOW PRESSURE OFF THE SOUTH CAROLINA COAST WILL FLING SOME LIGHT MOISTURE ONSHORE TO NORTH CAROLINA. THE LOW WILL PULL NORTHEAST THIS AFTERNOON...TAKING ITS MOISTURE WITH IT. SOME LOW LEVEL MOISTURE WILL REMAIN TONIGHT...HOWEVER MUCH LESS FOG/STRATUS THAN THIS MORNING. EXTENDED OUTLOOK...ISOLATED SHOWERS WED. SCATTERED SHOWERS LATE THURSDAY WITH A BETTER CHANCE FOR CONVECTION FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM TUESDAY...AN OLD STALLED FRONT RUNS ALONG THE BEACHES OF SE NORTH CAROLINA SOUTHWARD INTO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. HURRICANE BERTHA IS WELL EAST OF THE CAROLINAS AND WILL MOVE NORTHEASTWARD AND FARTHER AWAY TODAY. THE GEORGIA LOW AND OUR FRONT SHOULD BE DRAWN OFFSHORE TOWARD BERTHA...LEADING TO A DRYING TREND DEVELOPING WITH TIME. UNTIL THEN...WAVES OF SHOWERS AND EMBEDDED T-STORMS ACROSS THE COASTAL WATERS SHOULD CONTINUE THROUGH THE MORNING HOURS. GENERALLY EAST OR NORTHEAST WINDS WILL TURN NORTHERLY THIS EVENING...THEN WESTERLY OVERNIGHT AS BERTHA PULLS THE LOW AND FRONT AWAY FROM THE AREA. THIS WILL LET DRIER AIR FLOOD INTO THE AREA. A SIGNIFICANT SWELL FROM BERTHA WILL IMPACT THE WATERS TODAY AND SHOULD BE THE LARGEST CONTRIBUTING FACTOR IN SEA HEIGHT FORECASTS TODAY. SEAS OF 4-5 FEET ARE EXPECTED...DIMINISHING TO 3-4 FT LATE TONIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...PIEDMONT TROUGH ON WEDNESDAY WILL BACK INITIALLY WEST FLOW TO SOUTHWEST OR EVEN SOUTH WHILE ADDING A FEW KNOTS TO AVERAGE SPEED. SEAS MAINLY COMPRISED OF WIND WAVES IN THE 2 TO 3 FT RANGE. AS THE BOUNDARY MOVES TOWARDS THE COAST ON THURSDAY THE WIND WILL DIMINISH LATER IN THE DAY AS THE GRADIENT IS PUSHED OUT TO SEA BY THE TROUGH. THE BOUNDARY WILL SINK SOUTH ACROSS THE ZONES RATHER SLOWLY LATE THURSDAY NIGHT BRINGING A TURN TO NORTHERLY WINDS FOLLOWED BY ADDITIONAL VEERING TO EASTERLY BY THE PERIODS END...AT LEAST FOR NORTHERN ZONES. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...POST-FRONTAL ONSHORE FLOW ON FRIDAY WILL BE IN THE 10 TO 15 KT RANGE EARLY BUT SETTLE BY ABOUT 5 KT. SEAS WILL BE RUNNING JUST 2-3 FEET THEN MOST AREAS. THE HIGH WILL CONTINUE WEDGING IN FROM POINTS NORTH INTO SATURDAY WHILE THE FRONT STALLED TO THE SOUTH TRIES TO MOVE BACK TO THE NORTH SLIGHTLY. WITH RELATIVELY UNCHANGED WINDS AND NO SWELL ENERGY TO SPEAK OF SEAS WILL REMAIN 2 FEET AGAIN ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...TRA SHORT TERM...MBB LONG TERM...MBB AVIATION...43
AREA FORECAST DISCUSSION
NWS RALEIGH NC
333 AM EDT TUE AUG 5 2014 .SYNOPSIS...LOW PRESSURE MOVES NORTHEAST JUST OFF OF THE CAROLINA COAST TODAY THROUGH THIS EVENING. WEAK HIGH PRESSURE WILL BE LOCATED OVER THE APPALACHIANS. A COLD FRONT MOVES SOUTH OVER THE REGION WEDNESDAY AFTERNOON INTO THURSDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 305 AM TUESDAY... WITH LOW PRESSURE OFF OF THE CAROLINA COAST...THE LATEST IR FOG SATELLITE IMAGE SHOWED THE WESTERN EDGE OF A SHIELD OF MID- AND HIGH- LEVEL CLOUDS MAINLY ALONG AND EAST OF ABOUT U.S. 1...WITH PATCHY CIRRUS TOWARD THE TRIAD. UNDERNEATH THE HIGHER CLOUDS OBSERVATIONS SHOWED SOME LOW CLOUDS HAD FORMED...AND IT WAS NEAR THE WESTERN EDGE OF THE HIGHER CLOUDS THAT VISIBILITIES WERE LOWEST...PARTICULARLY TOWARD KHNZ AND FOR A TIME NEAR KTTA. AS NOTED IN THE AVIATION DISCUSSION BELOW...THE HRRR WRF EARLY THIS MORNING HAS BEEN CONSISTENT IN DEVELOPING THE LOWER-VISIBILITY FOG MAINLY FROM THE TRIANGLE NORTHEAST...WHICH SEEMS REASONABLE GIVEN THE ORIENTATION OF THE CLOUD SHIELD ALOFT AND THE LIGHT NORTHEAST LOW-LEVEL FLOW. THE GRIDDED FORECAST WILL NOTE AREAS OF FOG AND PATCHY DRIZZLE MAINLY FROM THE TRIANGLE NORTH AND NORTHEAST...WITH A SLIGHT CHANCE OF SHOWERS EARLY THIS MORNING ALONG AND EAST OF INTERSTATE 95 IN THE DEEPER MOISTURE CLOSER TO THE COASTAL LOW PRESSURE. WHILE THE RAP AND HRRR WRF ARE DRY IN CENTRAL NORTH CAROLINA TODAY...THE NAM HAS COPIOUS PRECIPITATION OVER A QUARTER-INCH IN A LARGE PART OF THE COASTAL PLAIN TODAY. LEANED WITH THIS FORECAST MORE TOWARD THE DRIER GUIDANCE...AS DRIER MID-LEVEL AIR WAS SLOWLY MOVING EAST INTO THE WESTERN PART OF THE STATE ON THE LATEST WATER VAPOR IMAGERY...AND ONLY WEAK LIFT FORECAST. GFS BUFR SOUNDINGS ARE STABLE...AND MEAN LAYER RELATIVE HUMIDITY IS FORECAST TO DECREASE GRADUALLY DURING THE DAY ON BOTH THE NAM AND GFS AS PRECIPITABLE WATER VALUES ALSO SLOWLY FALL. IT SHOULD BE NOTED THAT WITH THE BETTER MID-LEVEL WINDS MOVING THROUGH EARLY THIS MORNING...THERE HAVE BEEN A COUPLE OF SHOWERS THAT HAVE DEVELOPED VERY BRIEFLY OVER UPSTATE SOUTH CAROLINA. WILL CERTAINLY MONITOR RADAR TRENDS...BUT FOR NOW THE FORECAST WILL ONLY SHOW A SLIGHT CHANCE OF A SHOWER ALONG AND EAST OF ABOUT U.S. 1 WITH A CHANCE OF A SHOWER OR THUNDERSTORM FROM INTERSTATE 95 EAST. 1000- 850MB THICKNESSES SUPPORT HIGHS IN THE UPPER 80S...AND WHEN MORNING CLOUDS ARE CONSIDERED...WILL FORECAST HIGHS IN THE MID TO UPPER 80S UNDER A NORTH-TO-NORTHEAST WIND 10 MPH OR LESS. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AS OF 305 AM TUESDAY... BUFR SOUNDINGS ARE STABLE OVERNIGHT ON BOTH THE NAM AND THE GFS...WITH THE GFS IN PARTICULAR SHOWING A SMALL VOLUME OF MID-LEVEL MOISTURE AS THE TROUGH AXIS ALOFT MOVES THROUGH AND A WEAK MID-LEVEL SHORTWAVE FOLLOWS THE TROUGH AXIS OVERNIGHT IN THE NORTHWEST FLOW. THIS SHOULD TRANSLATE INTO A PERIOD OF SCATTERED MID-LEVEL CLOUDS... POSSIBLY BROKEN FOR A PERIOD IF THE GFS VERIFIES. LOW-LEVEL MOISTURE REMAINS BEST TOWARD INTERSTATE 95 AND MAY NOTE PATCHY FOG POSSIBLE IN THE GRIDDED AND WORDED FORECASTS FOR THOSE AREAS LATE TONIGHT INTO VERY EARLY WEDNESDAY. OVERNIGHT LOWS 65 TO 70. WEDNESDAY AND WEDNESDAY NIGHT...GFS BUFR SOUNDINGS ARE STABLE WEDNESDAY...WHILE THE NAM SHOWS MODEST INSTABILITY PARTICULARLY TOWARD KRWI AND KFAY. ALTHOUGH THE GFS POPS ARE LOW THROUGHOUT CENTRAL NORTH CAROLINA...ITS QPF DOES NOTE A MINOR HUNDREDTH OR SO TOWARD THE COASTAL PLAIN WEDNESDAY AFTERNOON. SURFACE DEW POINTS SHOULD GENERALLY MIX WELL BASED ON THE BUFR SOUNDINGS AND A DEVELOPING WESTERLY SURFACE FLOW...MIXING LAST TOWARD THE COASTAL PLAIN WHERE THE COMBINATION OF JUST ENOUGH INSTABILITY...WEAK 850MB CONVERGENCE AND GRADUALLY LOWERING DEW POINTS COULD RESULT IN A VERY ISOLATED SHOWER OR STORM. THE MEAN AIR MASS STARTS TO MOISTEN WEDNESDAY NIGHT WITH THE APPROACH OF THE SURFACE FRONT...BUT WITH ONLY WEAK MID-LEVEL SUPPORT AND JET DYNAMICS NORTH OF THE AREA IN VIRGINIA...WILL LEAN TOWARD THE GFS AS OPPOSED TO THE WET NAM AND SHOW A DRY OVERNIGHT WEDNESDAY WITH AN EXPECTED INCREASE IN MID- LEVEL CLOUDS OVER MUCH OF THE AREA. 1000-850MB THICKNESSES SUPPORT HIGHS OF A BLEND OF MAV AND MET MOS GUIDANCE...OR 90 TO 95. OVERNIGHT LOWS WEDNESDAY NIGHT WITHIN A DEGREE OR THREE OF 70. -DJF THU/THU NIGHT: AN UPPER LEVEL TROUGH OVER NEW ENGLAND WILL LIFT INTO THE CANADIAN MARITIMES THU/THU NIGHT...WITH A WEAKENED WNW FLOW ALOFT OVER THE CAROLINAS. SUBSIDENCE IN THE WAKE OF THE TROUGH WILL RESULT IN SFC PRESSURE RISES OVER THE OH VALLEY AND MID ATLANTIC...WITH AN ATTENDANT SFC RIDGE AXIS /BACKDOOR COLD FRONT/ EXTENDING SOUTHWARD THROUGH VA TOWARD THE NC BORDER LATE THU. UNCERTAINTY PERSISTS W/REGARD TO THE TIMING/PROGRESS OF THE BACK DOOR COLD FRONT...LENDING A FAIR AMOUNT OF UNCERTAINTY TO TEMPERATURES...ESP ALONG AND NORTH OF HWY 64. AT THIS TIME WILL INDICATE HIGHS RANGING FROM ~90F SOUTH TO 83-85F NEAR THE VA BORDER. DESTABILIZATION/FORCING WILL HIGHLY DEPEND ON BOTH THE EVOLUTION OF THE FRONT AND OF SMALL AMPLITUDE DISTURBANCES IN WNW FLOW ALOFT... WITH CONSIDERABLE UNCERTAINTY IN PRECIP CHANCES/COVERAGE. AT THIS TIME WILL INDICATE A SLIGHT CHANCE DURING THE LATE AFTERNOON/EVENING HOURS. -VINCENT && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 AM TUESDAY... THE 00Z GFS/ECMWF ARE IN RELATIVELY GOOD AGREEMENT ON THE SYNOPTIC PATTERN FRI-MON. DESPITE GOOD SYNOPTIC AGREEMENT...SIGNIFICANT DISAGREEMENT ON MESOSCALE FEATURES AND CONVECTIVE EVOLUTION THROUGHOUT THE LONG TERM PERIOD LENDS ABOVE NORMAL UNCERTAINTY WITH REGARD TO PRECISE DETAILS (I.E. PRECIP AMOUNTS AND TIMING) FOR THE CAROLINAS. NORTHWEST FLOW ALOFT WILL PREVAIL OVER THE CAROLINAS FRI/SAT... DOWNSTREAM OF AN UPPER LEVEL RIDGE CENTERED OVER THE CENTRAL PLAINS/LOWER MIDWEST. THE UPPER LEVEL RIDGE IS PROGGED TO AMPLIFY AND RETROGRADE INTO THE ROCKIES ON SUN/MON...RESULTING IN A MORE AMPLIFIED PATTERN OF NNW FLOW ALOFT DOWNSTREAM OVER THE CAROLINAS. GIVEN AN ACTIVE UPPER LEVEL PATTERN JUXTAPOSED WITH MID-SUMMER MOISTURE...EXPECT ABOVE NORMAL CHANCES FOR PRECIPITATION AND BELOW NORMAL TEMPERATURES...PARTICULARLY SAT/SUN. -VINCENT && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 155 AM TUESDAY... PATCHY MVFR AND IFR CONDITIONS IN FOG AND LOW CLOUDS WILL CONTINUE OVER CENTRAL NORTH CAROLINA DURING THE EARLY MORNING. THE LATEST SATELLITE IMAGES COMBINED WITH OBSERVATIONS SHOWED SOME LOWER CLOUDS TRYING TO MOVE TOWARD KINT...WITH A FEW LOW CLOUDS VISIBLE UNDERNEATH HIGHER CLOUDS IN THE SOUTHWEST FLOW ALOFT. FOG HAS BEEN DIFFICULT TO DEVELOP DUE TO THE MID- AND HIGH-LEVEL CLOUDS...AND THIS LIKELY WILL CONTINUE DURING THE REST OF THE MORNING. LIGHT FOG SEEMS REASONABLE...WITH THE HRRR WRF MODEL SHOWING THE BEST POTENTIAL FOR SOLID IFR FOG DEVELOPMENT ORIGINATING OVER SOUTHERN VIRGINIA WHERE THERE ARE FEWER MID- AND HIGH-LEVEL CLOUDS...THEN MOVING SOUTH-SOUTHWEST IN THE LIGHT LOW-LEVEL FLOW FROM ABOUT 07Z TO 12Z. THIS SEEMS A PLAUSIBLE SCENARIO...AND HAVE ACCOUNTED FOR THIS IN THE TAFS WITH THE LOWEST VISIBILITY FOR A PERIOD DURING THE EARLY MORNING AT KRWI AND KRDU. AS LOW PRESSURE MOVES NORTHEAST OFF OF THE CAROLINA COAST THERE IS AN OUTSIDE CHANCE OF A SHOWER MAINLY ALONG AND EAST OF INTERSTATE 95...BUT THE CHANCES SEEM TOO LOW TO INCLUDE IN A TAF POINT FORECAST. VFR CONDITIONS SHOULD PREVAIL OVER CENTRAL NORTH CAROLINA BY AFTERNOON UNDER A NORTHEAST WIND. EVENING WINDS... LIGHT AND VARIABLE...MAY SHOW A TENDENCY TO BECOME LIGHT SOUTHERLY BY THE END OF THE 06Z VALID TAF PERIOD. BEYOND THE 06Z VALID TAF PERIOD...PATCHY FOG AND SUB-VFR CONDITIONS ARE POSSIBLE LATE TONIGHT INTO EARLY WEDNESDAY...WITH THE BETTER CHANCES OF SUCH TOWARD KFAY AND KRWI. BEHIND A COLD FRONT WHICH SETTLES JUST SOUTH OF THE AREA BY LATE THURSDAY...CHANCES FOR PRECIPITATION WILL INCREASE. INTO SATURDAY...THE HIGHER CHANCES AS THEY DEVELOP ARE EXPECTED TO BE OVER THE SOUTHWEST PIEDMONT INTO THE SANDHILLS. STILL...AREAS OF SUB-VFR CONDITIONS IN LOWER CLOUDS ARE POSSIBLE THROUGHOUT MUCH OF CENTRAL NORTH CAROLINA DEVELOPING SATURDAY OR ESPECIALLY SATURDAY NIGHT. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...DJF/VINCENT LONG TERM...VINCENT AVIATION...DJF
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
320 AM EDT TUE AUG 5 2014 .SYNOPSIS... A STALLED FRONT ALONG THE COAST WILL MOVE OFFSHORE TODAY AS HURRICANE BERTHA MOVES PASSES WELL OFFSHORE OF THE CAROLINA COAST. SWELLS FROM BERTHA WILL LEAD TO AN INCREASED RIP CURRENT RISK ALONG AREA BEACHES THE NEXT SEVERAL DAYS. WARM AND MUGGY WEATHER IS EXPECTED WEDNESDAY AND THURSDAY AHEAD OF AN APPROACHING COLD FRONT. HIGH PRESSURE WILL BUILD IN FRIDAY THROUGH THE WEEKEND...LIKELY HOLDING TEMPERATURES DOWN A FEW DEGREES BELOW NORMAL. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM TUESDAY...WE ARE JUST ABOUT TO GET RID OF THE DREARY WEATHER PATTERN THAT HAS BROUGHT UNSEASONABLY COOL...CLOUDY AND RAINY WEATHER TO THE COASTAL CAROLINAS FOR THE ENTIRE MONTH SO FAR. SO FAR AUGUST 2014 HAS SEEN THE 7TH COOLEST TEMPERATURES EVEN OBSERVED IN WILMINGTON WITH AN AVERAGE TEMPERATURE OF ONLY 75.7 DEGREES. HURRICANE BERTHA IS PASSING WELL EAST OF THE CAROLINAS WITH NO DIRECT IMPACTS ON OUR WEATHER TODAY. THE OLD STALLED FRONT APPEARS TO LIE ALONG THE BEACHES OF PENDER AND NEW HANOVER COUNTIES... EXTENDING SOUTHWARD FROM SOUTHPORT TO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. THIS FEATURE SHOULD BE DRAWN EASTWARD BEHIND BERTHA TODAY...WITH DRIER AIR GRADUALLY BUILDING IN FROM THE NORTH WITH TIME. RADAR SHOWS PLENTY OF SHOWERS ACROSS THE COASTAL WATERS. THESE ARE SHALLOW CONVECTIVE FEATURES WITH ECHO TOPS GENERALLY 20KFT OR LESS...EXCEPT FOR A FEW T-STORMS FARTHER OFFSHORE WITH TOPS OVER 30KFT. SINCE THE BULK OF THIS ACTIVITY IS SHALLOW IT IS BEING STEERED BY THE 700-850 MB MEAN FLOW WHICH IS CURRENTLY FROM THE EAST. THE 00Z GFS AND 06Z RUC (OUR PREFERRED MODELS TODAY) SHOW THIS STEERING FLOW BACKING MORE NORTHERLY WITH TIME WHICH SHOULD TEND TO LIMIT HOW FAR INLAND ANY SHOWER ACTIVITY WILL MOVE. FORECAST POPS RANGE FROM 30-50 PERCENT ALONG THE COAST THIS MORNING...DIMINISHING TO 20-30 PERCENT BY NOON. FOR INTERIOR SECTIONS OF THE EASTERN CAROLINAS UNLESS AN ISOLATED SHOWER CAN DEVELOP DURING THE AFTERNOON DRY WEATHER IS EXPECTED. HIGHS SHOULD RANGE FROM THE UPPER 80S TO NEAR 90 ACROSS THE SC PEE DEE REGION TO THE MID 80S AT THE COAST. FOR TONIGHT DRY AIR SHOULD FLOOD IN THROUGHOUT THE TROPOSPHERE WITH PRECIPITABLE WATER VALUES FALLING TO LESS THAN 1.5 INCHES. SKIES SHOULD BECOME MAINLY CLEAR BY EARLY EVENING AND THERE IS LITTLE POTENTIAL FOR FOG OR LOW STRATUS OVERNIGHT. LOWS SHOULD TO NEAR 70. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...SUMMER RETURNS ON WEDNESDAY AS THE MID LEVEL FLOW GOES WESTERLY AND DOWNSLOPE ALLOWING FOR A PARTLY SUNNY AFTERNOON. PIEDMONT TROUGH DEVELOPS BUT IT ALONG WITH THE SEA BREEZE WILL GENERALLY BE TOO MOISTURE-DEPRIVED TO LEAD TO MEANINGFUL PRECIP CHANCES. AFTERNOON TEMPERATURES WILL BE NEAR OR A FEW DEGREES ABOVE CLIMO. PIEDMONT TROUGH PUSHES TOWARDS THE COAST ON THURSDAY WHILE A MID LEVEL SHORTWAVE PASSES OVERHEAD LATE IN THE AFTERNOON. NORMALLY THIS WOULD BE A GOOD SETUP FOR THUNDERSTORMS. HOWEVER THERE IS STILL VERY LITTLE MOISTURE ESPECIALLY THROUGH THE MID LEVELS. CONVECTION WILL BE LIMITED AND GENERALLY BE CONFINED TO THE COASTAL REGIONS. TEMPERATURES WILL BE QUITE SIMILAR TO THOSE OF WEDNESDAY. A COLD FRONT WILL ENTER THE REGION LATE THURSDAY NIGHT AND WILL KEEP ISOLATED SHOWERS AND THUNDERSTORMS IN THE FORECAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 3 AM TUESDAY...HIGH PRESSURE BUILDING IN FROM THE NORTH BEHIND THURSDAY NIGHT COLD FRONT TO END THE BRIEF SHORT TERM PERIODS SUMMER TEMPS. MOISTURE MAY POOL ALONG THE FRONT AND BRING SOME SLIGHT RAIN CHANCES OVER SWRN ZONES. THIS WILL HOLD TRUE INTO SATURDAY AS THE FRONT WASHES BACK CLOSER TO THE AREA...THE LOW RAIN CHANCES MAY INCREASE IN AREA WHILE AFTERNOON HIGHS REMAIN CAPPED BELOW CLIMO. SUNDAY IS WHEN RAIN CHANCES SHOULD RETURN AREA-WIDE AS THE FRONT LIFTS BACK INTO THE REGION. WAVE MOVES BY LATE SUNDAY INTO SUNDAY NIGHT POSSIBLY FURTHER RAMPING UP RAIN CHANCES...AND THEN LEAVING THE BOUNDARY IN OUR PRESENCE SANS WAVE ON MONDAY. CYCLONIC AND NWRLY MID LEVEL FLOW CONTINUES ON TUESDAY WITH SURFACE TROUGHINESS REDEVELOPING. RAIN CHANCES WILL LINGER INTO TUESDAY WITH CLIMO OR HIGHER CHANCES WHILE TEMPS REMAIN NEAR OR JUST SHY OF CLIMO. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...EARLY THIS MORNING ISOLATED SHOWERS EXTEND ALONG THE COAST. THROUGH 10Z THE BEST CHANCE OF CONVECTIVE SHRA/ISOLATED TSRA /MVFR CIGS WILL BE AT THE COASTAL TERMINALS WHERE THE BEST LIFT WILL BE. CANNOT RULE OUT SOME SCT IFR LEVEL CLOUDS BUT CHANCES OF IFR CIGS APPEAR LOW. THE CONVECTIVE SHRA/ISOLATED TSRA SHOULD BECOME PATCHY -RA AFTER 10Z OR SO AS DEEPER LIFT ABATES. -RA SHOULD END SHORTLY AFTER SUNRISE. AT KFLO/KLBT MVFR VSBYS IN BR EARLY THIS MORNING WILL LOWER TO LIFR VSBYS/CIGS IN FG/ST AROUND 09Z. FLIGHT CONDITIONS SHOULD IMPROVE TO VFR SHORTLY AFTER SUNRISE. EXPECT VFR IN THE MORNING HOURS TO CONTINUE THROUGH THE END OF THE TAF VALID PERIOD. ISOLATED SHOWERS WILL DEVELOP MAINLY COASTAL TERMINALS AFTER 15Z WHICH SHOULD ABATE IN THE LATE AFTERNOON. EXTENDED OUTLOOK...ISOLATED SHOWERS WED. SCATTERED SHOWERS LATE THURSDAY WITH A BETTER CHANCE FOR CONVECTION FRIDAY AND SATURDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 AM TUESDAY...AN OLD STALLED FRONT RUNS ALONG THE BEACHES OF SE NORTH CAROLINA SOUTHWARD INTO AN AREA OF LOW PRESSURE OFF THE GEORGIA COAST. HURRICANE BERTHA IS WELL EAST OF THE CAROLINAS AND WILL MOVE NORTHEASTWARD AND FARTHER AWAY TODAY. THE GEORGIA LOW AND OUR FRONT SHOULD BE DRAWN OFFSHORE TOWARD BERTHA...LEADING TO A DRYING TREND DEVELOPING WITH TIME. UNTIL THEN...WAVES OF SHOWERS AND EMBEDDED T-STORMS ACROSS THE COASTAL WATERS SHOULD CONTINUE THROUGH THE MORNING HOURS. GENERALLY EAST OR NORTHEAST WINDS WILL TURN NORTHERLY THIS EVENING...THEN WESTERLY OVERNIGHT AS BERTHA PULLS THE LOW AND FRONT AWAY FROM THE AREA. THIS WILL LET DRIER AIR FLOOD INTO THE AREA. A SIGNIFICANT SWELL FROM BERTHA WILL IMPACT THE WATERS TODAY AND SHOULD BE THE LARGEST CONTRIBUTING FACTOR IN SEA HEIGHT FORECASTS TODAY. SEAS OF 4-5 FEET ARE EXPECTED...DIMINISHING TO 3-4 FT LATE TONIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 3 AM TUESDAY...PIEDMONT TROUGH ON WEDNESDAY WILL BACK INITIALLY WEST FLOW TO SOUTHWEST OR EVEN SOUTH WHILE ADDING A FEW KNOTS TO AVERAGE SPEED. SEAS MAINLY COMPRISED OF WIND WAVES IN THE 2 TO 3 FT RANGE. AS THE BOUNDARY MOVES TOWARDS THE COAST ON THURSDAY THE WIND WILL DIMINISH LATER IN THE DAY AS THE GRADIENT IS PUSHED OUT TO SEA BY THE TROUGH. THE BOUNDARY WILL SINK SOUTH ACROSS THE ZONES RATHER SLOWLY LATE THURSDAY NIGHT BRINGING A TURN TO NORTHERLY WINDS FOLLOWED BY ADDITIONAL VEERING TO EASTERLY BY THE PERIODS END...AT LEAST FOR NORTHERN ZONES. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 3 AM TUESDAY...POST-FRONTAL ONSHORE FLOW ON FRIDAY WILL BE IN THE 10 TO 15 KT RANGE EARLY BUT SETTLE BY ABOUT 5 KT. SEAS WILL BE RUNNING JUST 2-3 FEET THEN MOST AREAS. THE HIGH WILL CONTINUE WEDGING IN FROM POINTS NORTH INTO SATURDAY WHILE THE FRONT STALLED TO THE SOUTH TRIES TO MOVE BACK TO THE NORTH SLIGHTLY. WITH RELATIVELY UNCHANGED WINDS AND NO SWELL ENERGY TO SPEAK OF SEAS WILL REMAIN 2 FEET AGAIN ON SATURDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...TRA SHORT TERM...MBB LONG TERM...MBB AVIATION...MRR
AREA FORECAST DISCUSSION
NWS RALEIGH NC
305 AM EDT TUE AUG 5 2014 .SYNOPSIS...LOW PRESSURE MOVES NORTHEAST JUST OFF OF THE CAROLINA COAST TODAY THROUGH THIS EVENING. WEAK HIGH PRESSURE WILL BE LOCATED OVER THE APPALACHIANS. A COLD FRONT MOVES SOUTH OVER THE REGION WEDNESDAY AFTERNOON INTO THURSDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 305 AM TUESDAY... WITH LOW PRESSURE OFF OF THE CAROLINA COAST...THE LATEST IR FOG SATELLITE IMAGE SHOWED THE WESTERN EDGE OF A SHIELD OF MID- AND HIGH- LEVEL CLOUDS MAINLY ALONG AND EAST OF ABOUT U.S. 1...WITH PATCHY CIRRUS TOWARD THE TRIAD. UNDERNEATH THE HIGHER CLOUDS OBSERVATIONS SHOWED SOME LOW CLOUDS HAD FORMED...AND IT WAS NEAR THE WESTERN EDGE OF THE HIGHER CLOUDS THAT VISIBILITIES WERE LOWEST...PARTICULARLY TOWARD KHNZ AND FOR A TIME NEAR KTTA. AS NOTED IN THE AVIATION DISCUSSION BELOW...THE HRRR WRF EARLY THIS MORNING HAS BEEN CONSISTENT IN DEVELOPING THE LOWER-VISIBILITY FOG MAINLY FROM THE TRIANGLE NORTHEAST...WHICH SEEMS REASONABLE GIVEN THE ORIENTATION OF THE CLOUD SHIELD ALOFT AND THE LIGHT NORTHEAST LOW-LEVEL FLOW. THE GRIDDED FORECAST WILL NOTE AREAS OF FOG AND PATCHY DRIZZLE MAINLY FROM THE TRIANGLE NORTH AND NORTHEAST...WITH A SLIGHT CHANCE OF SHOWERS EARLY THIS MORNING ALONG AND EAST OF INTERSTATE 95 IN THE DEEPER MOISTURE CLOSER TO THE COASTAL LOW PRESSURE. WHILE THE RAP AND HRRR WRF ARE DRY IN CENTRAL NORTH CAROLINA TODAY...THE NAM HAS COPIOUS PRECIPITATION OVER A QUARTER-INCH IN A LARGE PART OF THE COASTAL PLAIN TODAY. LEANED WITH THIS FORECAST MORE TOWARD THE DRIER GUIDANCE...AS DRIER MID-LEVEL AIR WAS SLOWLY MOVING EAST INTO THE WESTERN PART OF THE STATE ON THE LATEST WATER VAPOR IMAGERY...AND ONLY WEAK LIFT FORECAST. GFS BUFR SOUNDINGS ARE STABLE...AND MEAN LAYER RELATIVE HUMIDITY IS FORECAST TO DECREASE GRADUALLY DURING THE DAY ON BOTH THE NAM AND GFS AS PRECIPITABLE WATER VALUES ALSO SLOWLY FALL. IT SHOULD BE NOTED THAT WITH THE BETTER MID-LEVEL WINDS MOVING THROUGH EARLY THIS MORNING...THERE HAVE BEEN A COUPLE OF SHOWERS THAT HAVE DEVELOPED VERY BRIEFLY OVER UPSTATE SOUTH CAROLINA. WILL CERTAINLY MONITOR RADAR TRENDS...BUT FOR NOW THE FORECAST WILL ONLY SHOW A SLIGHT CHANCE OF A SHOWER ALONG AND EAST OF ABOUT U.S. 1 WITH A CHANCE OF A SHOWER OR THUNDERSTORM FROM INTERSTATE 95 EAST. 1000- 850MB THICKNESSES SUPPORT HIGHS IN THE UPPER 80S...AND WHEN MORNING CLOUDS ARE CONSIDERED...WILL FORECAST HIGHS IN THE MID TO UPPER 80S UNDER A NORTH-TO-NORTHEAST WIND 10 MPH OR LESS. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AS OF 305 AM TUESDAY... BUFR SOUNDINGS ARE STABLE OVERNIGHT ON BOTH THE NAM AND THE GFS...WITH THE GFS IN PARTICULAR SHOWING A SMALL VOLUME OF MID-LEVEL MOISTURE AS THE TROUGH AXIS ALOFT MOVES THROUGH AND A WEAK MID-LEVEL SHORTWAVE FOLLOWS THE TROUGH AXIS OVERNIGHT IN THE NORTHWEST FLOW. THIS SHOULD TRANSLATE INTO A PERIOD OF SCATTERED MID-LEVEL CLOUDS... POSSIBLY BROKEN FOR A PERIOD IF THE GFS VERIFIES. LOW-LEVEL MOISTURE REMAINS BEST TOWARD INTERSTATE 95 AND MAY NOTE PATCHY FOG POSSIBLE IN THE GRIDDED AND WORDED FORECASTS FOR THOSE AREAS LATE TONIGHT INTO VERY EARLY WEDNESDAY. OVERNIGHT LOWS 65 TO 70. WEDNESDAY AND WEDNESDAY NIGHT...GFS BUFR SOUNDINGS ARE STABLE WEDNESDAY...WHILE THE NAM SHOWS MODEST INSTABILITY PARTICULARLY TOWARD KRWI AND KFAY. ALTHOUGH THE GFS POPS ARE LOW THROUGHOUT CENTRAL NORTH CAROLINA...ITS QPF DOES NOTE A MINOR HUNDREDTH OR SO TOWARD THE COASTAL PLAIN WEDNESDAY AFTERNOON. SURFACE DEW POINTS SHOULD GENERALLY MIX WELL BASED ON THE BUFR SOUNDINGS AND A DEVELOPING WESTERLY SURFACE FLOW...MIXING LAST TOWARD THE COASTAL PLAIN WHERE THE COMBINATION OF JUST ENOUGH INSTABILITY...WEAK 850MB CONVERGENCE AND GRADUALLY LOWERING DEW POINTS COULD RESULT IN A VERY ISOLATED SHOWER OR STORM. THE MEAN AIR MASS STARTS TO MOISTEN WEDNESDAY NIGHT WITH THE APPROACH OF THE SURFACE FRONT...BUT WITH ONLY WEAK MID-LEVEL SUPPORT AND JET DYNAMICS NORTH OF THE AREA IN VIRGINIA...WILL LEAN TOWARD THE GFS AS OPPOSED TO THE WET NAM AND SHOW A DRY OVERNIGHT WEDNESDAY WITH AN EXPECTED INCREASE IN MID- LEVEL CLOUDS OVER MUCH OF THE AREA. 1000-850MB THICKNESSES SUPPORT HIGHS OF A BLEND OF MAV AND MET MOS GUIDANCE...OR 90 TO 95. OVERNIGHT LOWS WEDNESDAY NIGHT WITHIN A DEGREE OR THREE OF 70. -DJF THU/THU NIGHT: AN UPPER LEVEL TROUGH OVER NEW ENGLAND WILL LIFT INTO THE CANADIAN MARITIMES THU/THU NIGHT...WITH A WEAKENED WNW FLOW ALOFT OVER THE CAROLINAS. SUBSIDENCE IN THE WAKE OF THE TROUGH WILL RESULT IN SFC PRESSURE RISES OVER THE OH VALLEY AND MID ATLANTIC...WITH AN ATTENDANT SFC RIDGE AXIS /BACKDOOR COLD FRONT/ EXTENDING SOUTHWARD THROUGH VA TOWARD THE NC BORDER LATE THU. UNCERTAINTY PERSISTS W/REGARD TO THE TIMING/PROGRESS OF THE BACK DOOR COLD FRONT...LENDING A FAIR AMOUNT OF UNCERTAINTY TO TEMPERATURES...ESP ALONG AND NORTH OF HWY 64. AT THIS TIME WILL INDICATE HIGHS RANGING FROM ~90F SOUTH TO 83-85F NEAR THE VA BORDER. DESTABILIZATION/FORCING WILL HIGHLY DEPEND ON BOTH THE EVOLUTION OF THE FRONT AND OF SMALL AMPLITUDE DISTURBANCES IN WNW FLOW ALOFT... WITH CONSIDERABLE UNCERTAINTY IN PRECIP CHANCES/COVERAGE. AT THIS TIME WILL INDICATE A SLIGHT CHANCE DURING THE LATE AFTERNOON/EVENING HOURS. -VINCENT && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 300 PM MONDAY... THE OVERALL PATTERN IS SIMILAR BETWEEN THE GFS AND ECMWF...BUT WITH DIFFERENCES IN THE DETAILS. INTO FRIDAY...BOTH THE GFS AND THE ECMWF FORECAST THE SURFACE FRONT MAINLY BEING JUST SOUTH OF CENTRAL NORTH CAROLINA. SURFACE HIGH PRESSURE EDGES IN FROM THE NORTH PARTICULARLY ON THE GFS...BUT THE GFS GENERATES MUCH MORE QPF THROUGHOUT CENTRAL NORTH CAROLINA DUE TO THE 850MB FRONT BEING FARTHER NORTH WITH MUCH MORE MOISTURE ADVECTION AND 850MB CONVERGENCE ACROSS CENTRAL NORTH CAROLINA AS COMPARED TO THE ECMWF. THAT LATTER MODEL HAS THE BEST MOISTURE CONVERGENCE FARTHER SOUTH AND CLOSER TO THE SURFACE FRONT...AND NEARER ANY WAVES THAT MAY MOVE ALONG THE SURFACE FRONT. THE UPPER FLOW...INCLUDING A RIDGE AXIS TO OUR WEST...IS CONFLUENT AND FOR THIS PART OF THE FORECAST WILL LEAN MORE TOWARD THE ECMWF AND THE SURFACE PATTERN. THE FORECAST RESULT WILL BE HIGHER CHANCES FOR PRECIPITATION GENERALLY ALONG AND SOUTH OF U.S. 64...HIGHEST OVER THE SOUTHWEST PIEDMONT...WITH THE LEAST CHANCES OVER THE NORTHERN COASTAL PLAIN. WILL MAINTAIN THE CHANCE FOR THUNDER FRIDAY INTO FRIDAY NIGHT WHERE IT IS CURRENTLY FORECAST...BUT COARSE MODEL SOUNDINGS PARTICULARLY ON THE ECMWF TEND TO FAVOR LIMITED INSTABILITY AND THUNDER MAY BE SOMEWHAT ISOLATED. IF THE COARSE SOUNDINGS ARE CORRECT...WITH HIGH PRESSURE TRYING TO BUILD IN NORTH OF THE SURFACE FRONT...SATURDAY AT LEAST THROUGH MUCH OF THE MORNING COULD BE QUITE MURKY WITH LOW CLOUDS IN MANY AREAS. THE SURFACE FRONT MOVES LITTLE AND THE ORIENTATION OF THE CHANCES OF PRECIPITATION WILL CONTINUE THROUGH SATURDAY NIGHT SIMILAR TO FRIDAY. BOTH THE GFS AND THE ECMWF HAVE LIMITED QPF IN THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN AND THIS MAY EVENTUALLY VERIFY...BUT FOR THIS FORECAST WILL CONTINUE A SLIGHT CHANCE THERE DUE TO TIMING AND FEATURE LOCATION UNCERTAINTIES. INSTABILITY CONTINUES TO BE LIMITED AND WILL NOTE A SLIGHT CHANCE OF THUNDER FOR THE DAY SATURDAY CLOSER TO THE SURFACE BOUNDARY AND BETTER LIFT...SOUTH OF A LINE FROM ABOUT KINT TO KGSB. THE APPROACH AND PASSAGE OF A WEAK MID-LEVEL LOW ON THE ECMWF...AND A MODERATELY-STRONG MID-LEVEL SHORTWAVE ON THE GFS...RESULT IN INCREASING CHANCES FOR PRECIPITATION THROUGHOUT CENTRAL NORTH CAROLINA SUNDAY. WHILE THERE ARE SOME TIMING...LOCATION...AND STRENGTH DIFFERENCES BETWEEN THE GFS AND ECMWF...THE STRENGTHENING MID-LEVEL FEATURE TRANSLATES INTO A STRENGTHENING SURFACE WAVE SUNDAY AND SUNDAY NIGHT. THIS COULD RESULT IN A FAIRLY RAINY DAY INTO AT LEAST THE OVERNIGHT HOURS OF SUNDAY FOR A GOOD PORTION OF CENTRAL NORTH CAROLINA SOUTH OF U.S. 64. WILL NOT MENTION LIKELY CHANCES THERE THIS FAR OUT BUT THIS FORECAST WILL SHOW SOLIDLY HIGH CHANCES SUNDAY INTO SUNDAY NIGHT...BEFORE DRYING AND SUBSIDENCE... AT LEAST BRIEFLY...OCCUR BEHIND THE MID-LEVEL WAVE OR WEAK SURFACE LOW FROM WEST-TO-EAST MONDAY INTO MONDAY NIGHT. HIGH TEMPERATURES ARE A CHALLENGE...WITH CONCERNS ABOUT HOW WARM CONDITIONS WILL BECOME DUE TO THE PROXIMITY OF THE FRONT...THE ASSOCIATED CLOUD COVER...AND THE THREAT OF PRECIPITATION. SOME OF THE GRIDDED GUIDANCE FOR THE HIGHS DIFFER BY OVER 15 DEGREES...BUT IT IS INTERESTING...FOR EXAMPLE...HOW CONSISTENT RAW GFS AND ECMWF GRIDDED HIGH TEMPERATURE GUIDANCE IS FOR SUNDAY...KEEPING HIGHS ONLY IN THE 70S OVER MUCH OF THE AREA SOUTH OF U.S. 64 AND IN THE TRIAD...WARMING TO AROUND 80 NORTH OF THE TRIANGLE. WHILE OVERNIGHT LOWS SHOULD BE IN THE 60S...HIGH TEMPERATURES FORECAST WILL BE BELOW NORMAL AND MAINLY FROM THE MID 70S TO LOWER 80S EACH DAY...MOSTLY 80 TO 85 MONDAY IN THE EXPECTED DEVELOPING DRYING AND SUBSIDENCE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 155 AM TUESDAY... PATCHY MVFR AND IFR CONDITIONS IN FOG AND LOW CLOUDS WILL CONTINUE OVER CENTRAL NORTH CAROLINA DURING THE EARLY MORNING. THE LATEST SATELLITE IMAGES COMBINED WITH OBSERVATIONS SHOWED SOME LOWER CLOUDS TRYING TO MOVE TOWARD KINT...WITH A FEW LOW CLOUDS VISIBLE UNDERNEATH HIGHER CLOUDS IN THE SOUTHWEST FLOW ALOFT. FOG HAS BEEN DIFFICULT TO DEVELOP DUE TO THE MID- AND HIGH-LEVEL CLOUDS...AND THIS LIKELY WILL CONTINUE DURING THE REST OF THE MORNING. LIGHT FOG SEEMS REASONABLE...WITH THE HRRR WRF MODEL SHOWING THE BEST POTENTIAL FOR SOLID IFR FOG DEVELOPMENT ORIGINATING OVER SOUTHERN VIRGINIA WHERE THERE ARE FEWER MID- AND HIGH-LEVEL CLOUDS...THEN MOVING SOUTH-SOUTHWEST IN THE LIGHT LOW-LEVEL FLOW FROM ABOUT 07Z TO 12Z. THIS SEEMS A PLAUSIBLE SCENARIO...AND HAVE ACCOUNTED FOR THIS IN THE TAFS WITH THE LOWEST VISIBLITY FOR A PERIOD DURING THE EARLY MORNING AT KRWI AND KRDU. AS LOW PRESSURE MOVES NORTHEAST OFF OF THE CAROLINA COAST THERE IS AN OUTSIDE CHANCE OF A SHOWER MAINLY ALONG AND EAST OF INTERSTATE 95...BUT THE CHANCES SEEM TOO LOW TO INCLUDE IN A TAF POINT FORECAST. VFR CONDITIONS SHOULD PREVAIL OVER CENTRAL NORTH CAROLINA BY AFTERNOON UNDER A NORTHEAST WIND. EVENING WINDS... LIGHT AND VARIABLE...MAY SHOW A TENDENCY TO BECOME LIGHT SOUTHERLY BY THE END OF THE 06Z VALID TAF PERIOD. BEYOND THE 06Z VALID TAF PERIOD...PATCHY FOG AND SUB-VFR CONDITIONS ARE POSSIBLE LATE TONIGHT INTO EARLY WEDNESDAY...WITH THE BETTER CHANCES OF SUCH TOWARD KFAY AND KRWI. BEHIND A COLD FRONT WHICH SETTLES JUST SOUTH OF THE AREA BY LATE THURSDAY...CHANCES FOR PRECIPITATION WILL INCREASE. INTO SATURDAY...THE HIGHER CHANCES AS THEY DEVELOP ARE EXPECTED TO BE OVER THE SOUTHWEST PIEDMONT INTO THE SANDHILLS. STILL...AREAS OF SUB-VFR CONDITIONS IN LOWER CLOUDS ARE POSSIBLE THROUGHOUT MUCH OF CENTRAL NORTH CAROLINA DEVELOPING SATURDAY OR ESPECIALLY SATURDAY NIGHT. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...DJF/VINCENT LONG TERM...DJF AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
155 AM EDT TUE AUG 5 2014 .SYNOPSIS...LOW PRESSURE MOVES NORTHEAST JUST OFF OF THE CAROLINA COAST TODAY THROUGH THIS EVENING. WEAK HIGH PRESSURE WILL BE LOCATED OVER THE APPALACHIANS. A COLD FRONT MOVES SOUTH OVER THE REGION WEDNESDAY AFTERNOON INTO THURSDAY. && .NEAR TERM /THROUGH TUESDAY NIGHT/... AS OF 948 PM MONDAY... THE MAIN FORECAST PROBLEM OF THE NIGHT WILL AGAIN BE THE STATUS/FOG DEVELOPMENT. THE CURRENT DEW POINTS WERE IN THE MID 60S NW... AND 70+ IN THE SOUTH AND EAST. THE SKIES WERE MOSTLY CLEAR TO PARTLY CLOUDY. IT DOES APPEAR... BASED ON SATELLITE DATA... THAT THE VEIL OF HIGH CLOUDINESS THAT HAD BEEN DENSE EARLIER AS FAR WEST AS FAY AND RDU... WILL CONTINUE TO SHIFT AWAY OVERNIGHT. WITH WINDS NEARLY CALM UNDER WEAK RIDGING... THIS SHOULD ALLOW PLENTY OF OPPORTUNITY FOR COOLING TO THE SATURATION POINT... ESPECIALLY SE OF THE TRIAD REGION BETWEEN 06Z-12Z. WE WILL ADD AREAS OF FOG IN ALL BUT THE TRIAD... AND PLACE PATCHY FOG OVER IN THAT REGION. OTHERWISE... NO OTHER CHANGES WITH LOWS GENERALLY 65-70. CYCLONIC FLOW ALOFT WILL PERSIST OVER THE AREA ON TUESDAY...ALTHOUGH THE UPPER LEVEL TROUGH TO OUR WEST WILL BEGIN TO WEAKEN AND DEAMPLIFY AS IT SHIFTS EAST. IN ADDITION...THE STATIONARY FRONT WILL STILL BE NEAR/ALONG THE COAST. AS A RESULT...THE BEST PRECIP CHANCES WILL BE ACROSS THES EASTERN PORTIONS OF THE FORECAST AREA ONCE AGAIN. MOSTLY DRY CONDITIONS ARE EXPECTED ACROSS THE WEST AS SLIGHTLY DRIER AIR MOVES IN COURTESY OF THE FLOW ALOFT BECOMING MORE WEST/NORTHWESTERLY ASSOCIATED WITH THE EASTWARD PROGRESSION OF THE UPPER LEVEL TROUGH. THICKNESS VALUES ARE PROGGED TO INCREASE OVER TODAYS VALUES...WHICH SUPPORTS TEMPS CLIMBING INTO THE UPPER 80S. OVERNIGHT LOWS WILL ONCE AGAIN BE IN THE MID/UPPER 60S. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 315 PM MONDAY... WEDNESDAY THROUGH THURSDAY: EASTERN US TROUGH WILL PERSIST THROUGH THE PERIOD...ALBEIT UNDER WEAKENING INFLUENCE ACROSS THE SOUTHERN LATITUDES WITH INCREASINGLY WEST-NORTHWESTERLY FLOW ALOFT. SHORTWAVE TROUGH TRAVERSING THE NORTHERN MID-ATLANTIC STATES WILL HELP TO PROPEL A COLD FRONT SOUTHWARD INTO THE AREA LATE WEDNESDAY/WEDNESDAY NIGHT. PRECIP/RAIN CHANCES ALONG THE FRONT LATE WEDNESDAY-WEDNESDAY NIGHT WILL BE RATHER SCARCE...LIMITED BY THE W-NWLY DOWNSLOPE FLOW IN PLACE WHILE ANY APPRECIABLE SHORTWAVE DYNAMICS REMAINS NORTH OF THE AREA. ALL OF THIS WHILE MOVING INTO THE AREA DURING POOR DIURNAL TIMING WHICH IS FURTHER EXACERBATED BY THE PRESENCE OF A CAPPING INVERSION ALOFT IN ADVANCE OF THE FRONT WEDNESDAY AFTERNOON. INSTEAD...THE BETTER RAIN CHANCES LOOK TO BE DELAYED UNTIL LATE THURSDAY AFTERNOON/THURSDAY EVENING...MAINLY ACROSS THE SOUTHERN TIER WHERE DISTURBANCES EMBEDDED IN THE NWLY FLOW ALOFT LOOK TO INTERCEPT THE LINGERING FRONT ZONE. TEMPERATURES... WEDNESDAY WILL BE THE HOTTEST DAY OF THE WEEK WITH LOW-LEVEL THICKNESSES PROJECTED AOA 15-20 METERS ABOVE NORMAL... WHICH SHOULD EASILY SUPPORT HIGHS IN THE LOWER TO MID 90S. LOWS WEDNESDAY NIGHT IN THE MID 60S TO LOWER 70S SOUTH. AS FRONT SLIPS SLOWLY SOUTH THROUGH THE AREA ON WEDNESDAY NIGHT/EARLY THURSDAY...HIGHS THURSDAY WILL COOL OFF A GOOD BIT...ESPECIALLY ACROSS THE NORTHERN TIER. HIGHS THURSDAY RANGING FROM MID 80S NORTH TO AROUND 90 SOUTH. LOWS && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM MONDAY... THE OVERALL PATTERN IS SIMILAR BETWEEN THE GFS AND ECMWF...BUT WITH DIFFERENCES IN THE DETAILS. ON THURSDAY NIGHT INTO FRIDAY...BOTH THE GFS AND THE ECMWF FORECAST THE SURFACE FRONT MAINLY BEING JUST SOUTH OF CENTRAL NORTH CAROLINA. SURFACE HIGH PRESSURE EDGES IN FROM THE NORTH PARTICULARLY ON THE GFS...BUT THE GFS GENERATES MUCH MORE QPF THROUGHOUT CENTRAL NORTH CAROLINA DUE TO THE 850MB FRONT BEING FARTHER NORTH WITH MUCH MORE MOISTURE ADVECTION AND 850MB CONVERGENCE ACROSS CENTRAL NORTH CAROLINA AS COMPARED TO THE ECMWF. THAT LATTER MODEL HAS THE BEST MOISTURE CONVERGENCE FARTHER SOUTH AND CLOSER TO THE SURFACE FRONT...AND NEARER ANY WAVES THAT MAY MOVE ALONG THE SURFACE FRONT. THE UPPER FLOW...INCLUDING A RIDGE AXIS TO OUR WEST...IS CONFLUENT AND FOR THIS PART OF THE FORECAST WILL LEAN MORE TOWARD THE ECMWF AND THE SURFACE PATTERN. THE FORECAST RESULT WILL BE HIGHER CHANCES FOR PRECIPITATION GENERALLY ALONG AND SOUTH OF U.S. 64...HIGHEST OVER THE SOUTHWEST PIEDMONT...WITH THE LEAST CHANCES OVER THE NORTHERN COASTAL PLAIN. WILL MAINTAIN THE CHANCE FOR THUNDER FRIDAY INTO FRIDAY NIGHT WHERE IT IS CURRENTLY FORECAST...BUT COARSE MODEL SOUNDINGS PARTICULARLY ON THE ECMWF TEND TO FAVOR LIMITED INSTABILITY AND THUNDER MAY BE SOMEWHAT ISOLATED. IF THE COARSE SOUNDINGS ARE CORRECT...WITH HIGH PRESSURE TRYING TO BUILD IN NORTH OF THE SURFACE FRONT...SATURDAY AT LEAST THROUGH MUCH OF THE MORNING COULD BE QUITE MURKY WITH LOW CLOUDS IN MANY AREAS. THE SURFACE FRONT MOVES LITTLE AND THE ORIENTATION OF THE CHANCES OF PRECIPITATION WILL CONTINUE THROUGH SATURDAY NIGHT SIMILAR TO FRIDAY. BOTH THE GFS AND THE ECMWF HAVE LIMITED QPF IN THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN AND THIS MAY EVENTUALLY VERIFY...BUT FOR THIS FORECAST WILL CONTINUE A SLIGHT CHANCE THERE DUE TO TIMING AND FEATURE LOCATION UNCERTAINTIES. INSTABILITY CONTINUES TO BE LIMITED AND WILL NOTE A SLIGHT CHANCE OF THUNDER FOR THE DAY SATURDAY CLOSER TO THE SURFACE BOUNDARY AND BETTER LIFT...SOUTH OF A LINE FROM ABOUT KINT TO KGSB. THE APPROACH AND PASSAGE OF A WEAK MID-LEVEL LOW ON THE ECMWF...AND A MODERATELY-STRONG MID-LEVEL SHORTWAVE ON THE GFS...RESULT IN INCREASING CHANCES FOR PRECIPITATION THROUGHOUT CENTRAL NORTH CAROLINA SUNDAY. WHILE THERE ARE SOME TIMING...LOCATION...AND STRENGTH DIFFERENCES BETWEEN THE GFS AND ECMWF...THE STRENGTHENING MID-LEVEL FEATURE TRANSLATES INTO A STRENGTHENING SURFACE WAVE SUNDAY AND SUNDAY NIGHT. THIS COULD RESULT IN A FAIRLY RAINY DAY INTO AT LEAST THE OVERNIGHT HOURS OF SUNDAY FOR A GOOD PORTION OF CENTRAL NORTH CAROLINA SOUTH OF U.S. 64. WILL NOT MENTION LIKELY CHANCES THERE THIS FAR OUT BUT THIS FORECAST WILL SHOW SOLIDLY HIGH CHANCES SUNDAY INTO SUNDAY NIGHT...BEFORE DRYING AND SUBSIDENCE... AT LEAST BRIEFLY...OCCUR BEHIND THE MID-LEVEL WAVE OR WEAK SURFACE LOW FROM WEST-TO-EAST MONDAY INTO MONDAY NIGHT. HIGH TEMPERATURES ARE A CHALLENGE...WITH CONCERNS ABOUT HOW WARM CONDITIONS WILL BECOME DUE TO THE PROXIMITY OF THE FRONT...THE ASSOCIATED CLOUD COVER...AND THE THREAT OF PRECIPITATION. SOME OF THE GRIDDED GUIDANCE FOR THE HIGHS DIFFER BY OVER 15 DEGREES...BUT IT IS INTERESTING...FOR EXAMPLE...HOW CONSISTENT RAW GFS AND ECMWF GRIDDED HIGH TEMPERATURE GUIDANCE IS FOR SUNDAY...KEEPING HIGHS ONLY IN THE 70S OVER MUCH OF THE AREA SOUTH OF U.S. 64 AND IN THE TRIAD...WARMING TO AROUND 80 NORTH OF THE TRIANGLE. WHILE OVERNIGHT LOWS SHOULD BE IN THE 60S...HIGH TEMPERATURES FORECAST WILL BE BELOW NORMAL AND MAINLY FROM THE MID 70S TO LOWER 80S EACH DAY...MOSTLY 80 TO 85 MONDAY IN THE EXPECTED DEVELOPING DRYING AND SUBSIDENCE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 155 AM TUESDAY... PATCHY MVFR AND IFR CONDITIONS IN FOG AND LOW CLOUDS WILL CONTINUE OVER CENTRAL NORTH CAROLINA DURING THE EARLY MORNING. THE LATEST SATELLITE IMAGES COMBINED WITH OBSERVATIONS SHOWED SOME LOWER CLOUDS TRYING TO MOVE TOWARD KINT...WITH A FEW LOW CLOUDS VISIBLE UNDERNEATH HIGHER CLOUDS IN THE SOUTHWEST FLOW ALOFT. FOG HAS BEEN DIFFICULT TO DEVELOP DUE TO THE MID- AND HIGH-LEVEL CLOUDS...AND THIS LIKELY WILL CONTINUE DURING THE REST OF THE MORNING. LIGHT FOG SEEMS REASONABLE...WITH THE HRRR WRF MODEL SHOWING THE BEST POTENTIAL FOR SOLID IFR FOG DEVELOPMENT ORIGINATING OVER SOUTHERN VIRGINIA WHERE THERE ARE FEWER MID- AND HIGH-LEVEL CLOUDS...THEN MOVING SOUTH-SOUTHWEST IN THE LIGHT LOW-LEVEL FLOW FROM ABOUT 07Z TO 12Z. THIS SEEMS A PLAUSIBLE SCENARIO...AND HAVE ACCOUNTED FOR THIS IN THE TAFS WITH THE LOWEST VISIBLITY FOR A PERIOD DURING THE EARLY MORNING AT KRWI AND KRDU. AS LOW PRESSURE MOVES NORTHEAST OFF OF THE CAROLINA COAST THERE IS AN OUTSIDE CHANCE OF A SHOWER MAINLY ALONG AND EAST OF INTERSTATE 95...BUT THE CHANCES SEEM TOO LOW TO INCLUDE IN A TAF POINT FORECAST. VFR CONDITIONS SHOULD PREVAIL OVER CENTRAL NORTH CAROLINA BY AFTERNOON UNDER A NORTHEAST WIND. EVENING WINDS... LIGHT AND VARIABLE...MAY SHOW A TENDENCY TO BECOME LIGHT SOUTHERLY BY THE END OF THE 06Z VALID TAF PERIOD. BEYOND THE 06Z VALID TAF PERIOD...PATCHY FOG AND SUB-VFR CONDITIONS ARE POSSIBLE LATE TONIGHT INTO EARLY WEDNESDAY...WITH THE BETTER CHANCES OF SUCH TOWARD KFAY AND KRWI. BEHIND A COLD FRONT WHICH SETTLES JUST SOUTH OF THE AREA BY LATE THURSDAY...CHANCES FOR PRECIPITATION WILL INCREASE. INTO SATURDAY...THE HIGHER CHANCES AS THEY DEVELOP ARE EXPECTED TO BE OVER THE SOUTHWEST PIEDMONT INTO THE SANDHILLS. STILL...AREAS OF SUB-VFR CONDITIONS IN LOWER CLOUDS ARE POSSIBLE THROUGHOUT MUCH OF CENTRAL NORTH CAROLINA DEVELOPING SATURDAY OR ESPECIALLY SATURDAY NIGHT. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...PWB/KRD SHORT TERM...CBL LONG TERM...DJF AVIATION...DJF
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
933 AM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT NEAR LAKE ERIE WILL PUSH SOUTH ACROSS THE AREA TODAY. HIGH PRESSURE WILL PUSH SOUTHEAST OVER THE REGION BY THURSDAY...AND REMAIN OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... PREVIOUS FORECAST LOOKS ON TRACK AND HAVE ONLY MADE MINOR CHANGES TO THE TIMING OF THE CONVECTION THAT WILL DEVELOP. STORMS WILL BE SLOW MOVING BUT NOT AS SLOW AS OVER THE WEEKEND. SO THE SLOWER MOTION AND PRECIPITABLE WATER VALUES APPROACHING AN INCH AND A HALF COULD PRODUCE SOME LOCALLY HEAVY RAINFALL. PREVIOUS DISCUSSION... FIRST IN A SERIES OF TWO S/W TROUGHS WILL MOVE SE ACROSS THE AREA TODAY INDUCING A SURFACE TROUGH NEAR LERI TO MOVE SOUTH OF THE CWA BY TONIGHT. NEITHER THE SHEAR OR INSTABILITY ARE REAL IMPRESSIVE SO GENERALLY NOT EXPECTING MUCH IN THE WAY OF SEVERE STORMS. THE CONVECTION WILL TEND TO SHIFT SOUTH WITH THE TROUGH BUT ALSO TEND TO LINGER ON THE BACK EDGE AS THE MOISTURE HANGS BACK IN RESPONSE TO LIGHT WINDS DOING LITTLE TO FLUSH OUT THE LOW LEVEL MOISTURE. FOR EARLY MORNING UPDATE...DECREASED AND SLOWED POP INCREASE FOR NEXT FEW HOURS BASED ON LATEST DATA AND HRRR/RUC RUN. TEMPS TODAY WILL BE A LITTLE COOLER THAN YDAY DUE TO THE ADDED CLOUDS AND WINDS SHIFTING MORE TO THE NORTH. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... LINGERING MOISTURE AND UPPER TROUGHING SHOULD KEEP A THREAT FOR SHRA AND SOME THUNDER GOING TONIGHT FOR MOST OF THE AREA. THE SECOND S/W WILL DROP SE THRU THE REGION WED HELPING TO INDUCE CONVECTION. HOWEVER...LOW LEVEL FLOW WILL BE MAINLY N TO NE WHICH WILL LIMIT CONVERGENCE SO WILL PROBABLY JUST SEE SCATTERED COVERAGE WITH THE BETTER CHANCE PROBABLY OVER THE SOUTH HALF OF THE CWA. ONCE AGAIN...CONVECTIVE PARAMETERS ARE NOT OVERLY STRONG SO NO ORGANIZED SEVERE STORMS LOOK LIKELY. TEMPS WED SHOULD BE SIMILAR TO TUE AS NO SIGNIFICANT AIRMASS CHANGE HAS TAKEN PLACE. DRIER AIR SLOWLY FILTERS SOUTH INTO THE AREA WED NIGHT WHICH SHOULD SHIFT THE THREAT OF PRECIP SOUTH SO THINK THE RAIN SHOULD BE DONE THROUGHOUT THE CWA BY ABOUT MIDNIGHT WED NIGHT. TEMPS WED NIGHT SHOULD GET INTO A 55 TO 60 RANGE FOR MOST PLACES AS LIGHT N TO NE WINDS PERSIST AND CLOUDS DECREASE. THE NAM REMAINS CONSISTENT IN DEVELOPING A CONVECTIVE COMPLEX ON THE NE SIDE OF A LOW WED NIGHT IN IA AND MOVING THE COMPLEX ESE TO CROSS THE SW PART OF THE CWA LATE THU/THU NIGHT. NOT SEEING THIS ON OTHER MODELS ALTHOUGH THE GFS HAS INCHED SOME QPF INTO SW OH THU NIGHT. WILL MAINLY KEEP FORECAST DRY THU/THU NIGHT BUT WILL ALLOW FOR MORE CLOUDINESS OVER THE SW AND INTRODUCE A SLIGHT CHANCE POP. DAYTIME TEMPS THU AND FRI SHOULD BE PLEASANT WITH HIGHS MOSTLY IN THE MID TO UPPER 70S AND LOWS THU NIGHT IN THE 50S. && .LONG TERM /SATURDAY THROUGH MONDAY/... THE MODELS ARE NOT IN AGREEMENT WITH THIS PORTION OF THE FORECAST. THE 00Z GFS...00Z ECMWF AND CANADIAN MODEL SEEM TO HAVE THE SAME SURFACE AND UPPER AIR FEATURES...HOWEVER...THE ECMWF IS MUCH DRIER OVER THE WEEKEND AND THEN BY MONDAY IT HAS MORE MOISTURE TO SUPPORT SOME SHOWERS AND THUNDERSTORMS. EVEN OVER THE WEEKEND WITH HIGH PRESSURE TO THE NORTH OF THE FORECAST AREA...LOW PRESSURE IS OVER THE OHIO VALLEY AND SOME PRECIPITATION IS JUST SOUTH OF THE FORECAST AREA. AT THIS TIME KEPT THE WEEKEND DRY AND WENT WITH 20 POPS FOR MONDAY. TEMPERATURES WILL BE NEAR NORMAL. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... A WEAK COLD FRONT WILL BE MOVING FROM NORTH TO SOUTH TODAY...THE FRONT SHOULD BE SOUTH OF THE FORECAST AREA AROUND DARK. THE FRONT WILL MOVE THROUGH SLOWLY. THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT CLEAR CUT. A BATCH OF SHOWERS OVER NORTHERN INDIANA WILL DECREASE AS THEY MOVE EAST...SOME SHOWERS COULD GET INTO NORTHWEST OHIO AFTER DAYBREAK AND THEN CONTINUE TO WEAKEN AS THEY MOVE EAST. GOING ALONG WITH THE HRRR MODEL IN DEVELOPING SHOWERS AND THUNDERSTORMS BY EARLY IN THE AFTERNOON. MVFR OR IFR VISIBILITIES IN THE HEAVIER STORMS. OUTLOOK...NON VFR IN AREAS OF FOG WEDNESDAY MORNING. && .MARINE... A WEAK COLD FRONT WILL BE MOVING ACROSS LAKE ERIE FROM THE NORTH TODAY. SOME THUNDERSTORMS COULD OCCUR OVER THE LAKE...IT IS POSSIBLE THAT SOME OF THEM COULD PROMPT THE NEED FOR A SPECIAL MARINE WARNING. OTHERWISE BEHIND THE FRONT THE WINDS WILL BE FROM A NORTHERLY DIRECTION AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THE HIGH WILL SHIFT EAST OF LAKE ERIE FOR THE WEEKEND WITH THE WINDS BECOMING SOUTHERLY. IN THE MEANTIME NOT EXPECTING THE WINDS TO BE STRONG ENOUGH TO CAUSE 3 TO 5 FOOT WAVES...BUT THIS WILL HAVE TO BE MONITORED AS THAT DIRECTION CAN BE TRICKY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...ADAMS NEAR TERM...ADAMS/MULLEN SHORT TERM...ADAMS LONG TERM...KIELTYKA AVIATION...KIELTYKA MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
708 AM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT NEAR LAKE ERIE WILL PUSH SOUTH ACROSS THE AREA TODAY. HIGH PRESSURE WILL PUSH SOUTHEAST OVER THE REGION BY THURSDAY...AND REMAIN OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FIRST IN A SERIES OF TWO S/W TROUGHS WILL MOVE SE ACROSS THE AREA TODAY INDUCING A SURFACE TROUGH NEAR LERI TO MOVE SOUTH OF THE CWA BY TONIGHT. NEITHER THE SHEAR OR INSTABILITY ARE REAL IMPRESSIVE SO GENERALLY NOT EXPECTING MUCH IN THE WAY OF SEVERE STORMS. THE CONVECTION WILL TEND TO SHIFT SOUTH WITH THE TROUGH BUT ALSO TEND TO LINGER ON THE BACK EDGE AS THE MOISTURE HANGS BACK IN RESPONSE TO LIGHT WINDS DOING LITTLE TO FLUSH OUT THE LOW LEVEL MOISTURE. FOR EARLY MORNING UPDATE...DECREASED AND SLOWED POP INCREASE FOR NEXT FEW HOURS BASED ON LATEST DATA AND HRRR/RUC RUN. TEMPS TODAY WILL BE A LITTLE COOLER THAN YDAY DUE TO THE ADDED CLOUDS AND WINDS SHIFTING MORE TO THE NORTH. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... LINGERING MOISTURE AND UPPER TROUGHING SHOULD KEEP A THREAT FOR SHRA AND SOME THUNDER GOING TONIGHT FOR MOST OF THE AREA. THE SECOND S/W WILL DROP SE THRU THE REGION WED HELPING TO INDUCE CONVECTION. HOWEVER...LOW LEVEL FLOW WILL BE MAINLY N TO NE WHICH WILL LIMIT CONVERGENCE SO WILL PROBABLY JUST SEE SCATTERED COVERAGE WITH THE BETTER CHANCE PROBABLY OVER THE SOUTH HALF OF THE CWA. ONCE AGAIN...CONVECTIVE PARAMETERS ARE NOT OVERLY STRONG SO NO ORGANIZED SEVERE STORMS LOOK LIKELY. TEMPS WED SHOULD BE SIMILAR TO TUE AS NO SIGNIFICANT AIRMASS CHANGE HAS TAKEN PLACE. DRIER AIR SLOWLY FILTERS SOUTH INTO THE AREA WED NIGHT WHICH SHOULD SHIFT THE THREAT OF PRECIP SOUTH SO THINK THE RAIN SHOULD BE DONE THROUGHOUT THE CWA BY ABOUT MIDNIGHT WED NIGHT. TEMPS WED NIGHT SHOULD GET INTO A 55 TO 60 RANGE FOR MOST PLACES AS LIGHT N TO NE WINDS PERSIST AND CLOUDS DECREASE. THE NAM REMAINS CONSISTENT IN DEVELOPING A CONVECTIVE COMPLEX ON THE NE SIDE OF A LOW WED NIGHT IN IA AND MOVING THE COMPLEX ESE TO CROSS THE SW PART OF THE CWA LATE THU/THU NIGHT. NOT SEEING THIS ON OTHER MODELS ALTHOUGH THE GFS HAS INCHED SOME QPF INTO SW OH THU NIGHT. WILL MAINLY KEEP FORECAST DRY THU/THU NIGHT BUT WILL ALLOW FOR MORE CLOUDINESS OVER THE SW AND INTRODUCE A SLIGHT CHANCE POP. DAYTIME TEMPS THU AND FRI SHOULD BE PLEASANT WITH HIGHS MOSTLY IN THE MID TO UPPER 70S AND LOWS THU NIGHT IN THE 50S. && .LONG TERM /SATURDAY THROUGH MONDAY/... THE MODELS ARE NOT IN AGREEMENT WITH THIS PORTION OF THE FORECAST. THE 00Z GFS...00Z ECMWF AND CANADIAN MODEL SEEM TO HAVE THE SAME SURFACE AND UPPER AIR FEATURES...HOWEVER...THE ECMWF IS MUCH DRIER OVER THE WEEKEND AND THEN BY MONDAY IT HAS MORE MOISTURE TO SUPPORT SOME SHOWERS AND THUNDERSTORMS. EVEN OVER THE WEEKEND WITH HIGH PRESSURE TO THE NORTH OF THE FORECAST AREA...LOW PRESSURE IS OVER THE OHIO VALLEY AND SOME PRECIPITATION IS JUST SOUTH OF THE FORECAST AREA. AT THIS TIME KEPT THE WEEKEND DRY AND WENT WITH 20 POPS FOR MONDAY. TEMPERATURES WILL BE NEAR NORMAL. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... A WEAK COLD FRONT WILL BE MOVING FROM NORTH TO SOUTH TODAY...THE FRONT SHOULD BE SOUTH OF THE FORECAST AREA AROUND DARK. THE FRONT WILL MOVE THROUGH SLOWLY. THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT CLEAR CUT. A BATCH OF SHOWERS OVER NORTHERN INDIANA WILL DECREASE AS THEY MOVE EAST...SOME SHOWERS COULD GET INTO NORTHWEST OHIO AFTER DAYBREAK AND THEN CONTINUE TO WEAKEN AS THEY MOVE EAST. GOING ALONG WITH THE HRRR MODEL IN DEVELOPING SHOWERS AND THUNDERSTORMS BY EARLY IN THE AFTERNOON. MVFR OR IFR VISIBILITIES IN THE HEAVIER STORMS. OUTLOOK...NON VFR IN AREAS OF FOG WEDNESDAY MORNING. && .MARINE... A WEAK COLD FRONT WILL BE MOVING ACROSS LAKE ERIE FROM THE NORTH TODAY. SOME THUNDERSTORMS COULD OCCUR OVER THE LAKE...IT IS POSSIBLE THAT SOME OF THEM COULD PROMPT THE NEED FOR A SPECIAL MARINE WARNING. OTHERWISE BEHIND THE FRONT THE WINDS WILL BE FROM A NORTHERLY DIRECTION AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THE HIGH WILL SHIFT EAST OF LAKE ERIE FOR THE WEEKEND WITH THE WINDS BECOMING SOUTHERLY. IN THE MEANTIME NOT EXPECTING THE WINDS TO BE STRONG ENOUGH TO CAUSE 3 TO 5 FOOT WAVES...BUT THIS WILL HAVE TO BE MONITORED AS THAT DIRECTION CAN BE TRICKY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...ADAMS NEAR TERM...ADAMS SHORT TERM...ADAMS LONG TERM...KIELTYKA AVIATION...KIELTYKA MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
610 AM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT NEAR LAKE ERIE WILL PUSH SOUTH ACROSS THE AREA TODAY. HIGH PRESSURE WILL PUSH SOUTHEAST OVER THE REGION BY THURSDAY...AND REMAIN OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 PM TUESDAY EVENING/... FIRST IN A SERIES OF TWO S/W TROUGHS WILL MOVE SE ACROSS THE AREA TODAY INDUCING A SURFACE TROUGH NEAR LERI TO MOVE SOUTH OF THE CWA BY TONIGHT. NEITHER THE SHEAR OR INSTABILITY ARE REAL IMPRESSIVE SO GENERALLY NOT EXPECTING MUCH IN THE WAY OF SEVERE STORMS. THE CONVECTION WILL TEND TO SHIFT SOUTH WITH THE TROUGH BUT ALSO TEND TO LINGER ON THE BACK EDGE AS THE MOISTURE HANGS BACK IN RESPONSE TO LIGHT WINDS DOING LITTLE TO FLUSH OUT THE LOW LEVEL MOISTURE. FOR EARLY MORNING UPDATE...DECREASED AND SLOWED POP INCREASE FOR NEXT FEW HOURS BASED ON LATEST DATA AND HRRR/RUC RUN. TEMPS TODAY WILL BE A LITTLE COOLER THAN YDAY DUE TO THE ADDED CLOUDS AND WINDS SHIFTING MORE TO THE NORTH. && .SHORT TERM /6 PM TUESDAY EVENING THROUGH FRIDAY NIGHT/... LINGERING MOISTURE AND UPPER TROUGHING SHOULD KEEP A THREAT FOR SHRA AND SOME THUNDER GOING TONIGHT FOR MOST OF THE AREA. THE SECOND S/W WILL DROP SE THRU THE REGION WED HELPING TO INDUCE CONVECTION. HOWEVER...LOW LEVEL FLOW WILL BE MAINLY N TO NE WHICH WILL LIMIT CONVERGENCE SO WILL PROBABLY JUST SEE SCATTERED COVERAGE WITH THE BETTER CHANCE PROBABLY OVER THE SOUTH HALF OF THE CWA. ONCE AGAIN...CONVECTIVE PARAMETERS ARE NOT OVERLY STRONG SO NO ORGANIZED SEVERE STORMS LOOK LIKELY. TEMPS WED SHOULD BE SIMILAR TO TUE AS NO SIGNIFICANT AIRMASS CHANGE HAS TAKEN PLACE. DRIER AIR SLOWLY FILTERS SOUTH INTO THE AREA WED NIGHT WHICH SHOULD SHIFT THE THREAT OF PRECIP SOUTH SO THINK THE RAIN SHOULD BE DONE THROUGHOUT THE CWA BY ABOUT MIDNIGHT WED NIGHT. TEMPS WED NIGHT SHOULD GET INTO A 55 TO 60 RANGE FOR MOST PLACES AS LIGHT N TO NE WINDS PERSIST AND CLOUDS DECREASE. THE NAM REMAINS CONSISTENT IN DEVELOPING A CONVECTIVE COMPLEX ON THE NE SIDE OF A LOW WED NIGHT IN IA AND MOVING THE COMPLEX ESE TO CROSS THE SW PART OF THE CWA LATE THU/THU NIGHT. NOT SEEING THIS ON OTHER MODELS ALTHOUGH THE GFS HAS INCHED SOME QPF INTO SW OH THU NIGHT. WILL MAINLY KEEP FORECAST DRY THU/THU NIGHT BUT WILL ALLOW FOR MORE CLOUDINESS OVER THE SW AND INTRODUCE A SLIGHT CHANCE POP. DAYTIME TEMPS THU AND FRI SHOULD BE PLEASANT WITH HIGHS MOSTLY IN THE MID TO UPPER 70S AND LOWS THU NIGHT IN THE 50S. && .LONG TERM /SATURDAY THROUGH MONDAY/... THE MODELS ARE NOT IN AGREEMENT WITH THIS PORTION OF THE FORECAST. THE 00Z GFS...00Z ECMWF AND CANADIAN MODEL SEEM TO HAVE THE SAME SURFACE AND UPPER AIR FEATURES...HOWEVER...THE ECMWF IS MUCH DRIER OVER THE WEEKEND AND THEN BY MONDAY IT HAS MORE MOISTURE TO SUPPORT SOME SHOWERS AND THUNDERSTORMS. EVEN OVER THE WEEKEND WITH HIGH PRESSURE TO THE NORTH OF THE FORECAST AREA...LOW PRESSURE IS OVER THE OHIO VALLEY AND SOME PRECIPITATION IS JUST SOUTH OF THE FORECAST AREA. AT THIS TIME KEPT THE WEEKEND DRY AND WENT WITH 20 POPS FOR MONDAY. TEMPERATURES WILL BE NEAR NORMAL. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... A WEAK COLD FRONT WILL BE MOVING FROM NORTH TO SOUTH TODAY...THE FRONT SHOULD BE SOUTH OF THE FORECAST AREA AROUND DARK. THE FRONT WILL MOVE THROUGH SLOWLY. THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT CLEAR CUT. A BATCH OF SHOWERS AND THUNDERSTORMS OVER NORTHWEST INDIANA WILL DECREASE AS THEY MOVE EAST...SOME SHOWERS COULD GET INTO NW OHIO AFTER DAYBREAK AND THEN CONTINUE TO WEAKEN AS THEY MOVE EAST. GOING ALONG WITH THE HRRR MODEL IN DEVELOPING SHOWERS AND THUNDERSTORMS EARLY IN THE AFTERNOON. MVFR OR IFR VISIBILITIES IN THE HEAVIER STORMS. OUTLOOK...NON VFR IN AREAS OF FOG WEDNESDAY MORNING. && .MARINE... A WEAK COLD FRONT WILL BE MOVING ACROSS LAKE ERIE FROM THE NORTH TODAY. SOME THUNDERSTORMS COULD OCCUR OVER THE LAKE...IT IS POSSIBLE THAT SOME OF THEM COULD PROMPT THE NEED FOR A SPECIAL MARINE WARNING. OTHERWISE BEHIND THE FRONT THE WINDS WILL BE FROM A NORTHERLY DIRECTION AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THE HIGH WILL SHIFT EAST OF LAKE ERIE FOR THE WEEKEND WITH THE WINDS BECOMING SOUTHERLY. IN THE MEANTIME NOT EXPECTING THE WINDS TO BE STRONG ENOUGH TO CAUSE 3 TO 5 FOOT WAVES...BUT THIS WILL HAVE TO BE MONITORED AS THAT DIRECTION CAN BE TRICKY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...ADAMS NEAR TERM...ADAMS SHORT TERM...ADAMS LONG TERM...KIELTYKA AVIATION...KIELTYKA MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
303 AM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT NEAR LAKE ERIE WILL PUSH SOUTH ACROSS THE AREA TODAY. HIGH PRESSURE WILL PUSH SOUTHEAST OVER THE REGION BY THURSDAY...AND REMAIN OVER THE AREA THROUGH THE WEEKEND. && .NEAR TERM /UNTIL 6 PM TUESDAY EVENING/... FIRST IN A SERIES OF TWO S/W TROUGHS WILL MOVE SE ACROSS THE AREA TODAY INDUCING A SURFACE TROUGH NEAR LERI TO MOVE SOUTH OF THE CWA BY TONIGHT. NEITHER THE SHEAR OR INSTABILITY ARE REAL IMPRESSIVE SO GENERALLY NOT EXPECTING MUCH IN THE WAY OF SEVERE STORMS. THE CONVECTION WILL TEND TO SHIFT SOUTH WITH THE TROUGH BUT ALSO TEND TO LINGER ON THE BACK EDGE AS THE MOISTURE HANGS BACK IN RESPONSE TO LIGHT WINDS DOING LITTLE TO FLUSH OUT THE LOW LEVEL MOISTURE. TEMPS TODAY WILL BE A LITTLE COOLER THAN YDAY DUE TO THE ADDED CLOUDS AND WINDS SHIFTING MORE TO THE NORTH. && .SHORT TERM /6 PM TUESDAY EVENING THROUGH FRIDAY NIGHT/... LINGERING MOISTURE AND UPPER TROUGHING SHOULD KEEP A THREAT FOR SHRA AND SOME THUNDER GOING TONIGHT FOR MOST OF THE AREA. THE SECOND S/W WILL DROP SE THRU THE REGION WED HELPING TO INDUCE CONVECTION. HOWEVER...LOW LEVEL FLOW WILL BE MAINLY N TO NE WHICH WILL LIMIT CONVERGENCE SO WILL PROBABLY JUST SEE SCATTERED COVERAGE WITH THE BETTER CHANCE PROBABLY OVER THE SOUTH HALF OF THE CWA. ONCE AGAIN...CONVECTIVE PARAMETERS ARE NOT OVERLY STRONG SO NO ORGANIZED SEVERE STORMS LOOK LIKELY. TEMPS WED SHOULD BE SIMILAR TO TUE AS NO SIGNIFICANT AIRMASS CHANGE HAS TAKEN PLACE. DRIER AIR SLOWLY FILTERS SOUTH INTO THE AREA WED NIGHT WHICH SHOULD SHIFT THE THREAT OF PRECIP SOUTH SO THINK THE RAIN SHOULD BE DONE THROUGHOUT THE CWA BY ABOUT MIDNIGHT WED NIGHT. TEMPS WED NIGHT SHOULD GET INTO A 55 TO 60 RANGE FOR MOST PLACES AS LIGHT N TO NE WINDS PERSIST AND CLOUDS DECREASE. THE NAM REMAINS CONSISTENT IN DEVELOPING A CONVECTIVE COMPLEX ON THE NE SIDE OF A LOW WED NIGHT IN IA AND MOVING THE COMPLEX ESE TO CROSS THE SW PART OF THE CWA LATE THU/THU NIGHT. NOT SEEING THIS ON OTHER MODELS ALTHOUGH THE GFS HAS INCHED SOME QPF INTO SW OH THU NIGHT. WILL MAINLY KEEP FORECAST DRY THU/THU NIGHT BUT WILL ALLOW FOR MORE CLOUDINESS OVER THE SW AND INTRODUCE A SLIGHT CHANCE POP. DAYTIME TEMPS THU AND FRI SHOULD BE PLEASANT WITH HIGHS MOSTLY IN THE MID TO UPPER 70S AND LOWS THU NIGHT IN THE 50S. && .LONG TERM /SATURDAY THROUGH MONDAY/... THE MODELS ARE NOT IN AGREEMENT WITH THIS PORTION OF THE FORECAST. THE 00Z GFS...00Z ECMWF AND CANADIAN MODEL SEEM TO HAVE THE SAME SURFACE AND UPPER AIR FEATURES...HOWEVER...THE ECMWF IS MUCH DRIER OVER THE WEEKEND AND THEN BY MONDAY IT HAS MORE MOISTURE TO SUPPORT SOME SHOWERS AND THUNDERSTORMS. EVEN OVER THE WEEKEND WITH HIGH PRESSURE TO THE NORTH OF THE FORECAST AREA...LOW PRESSURE IS OVER THE OHIO VALLEY AND SOME PRECIPITATION IS JUST SOUTH OF THE FORECAST AREA. AT THIS TIME KEPT THE WEEKEND DRY AND WENT WITH 20 POPS FOR MONDAY. TEMPERATURES WILL BE NEAR NORMAL. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... A WEAK COLD FRONT WILL BE MOVING FROM NORTH TO SOUTH TODAY...THE FRONT SHOULD BE SOUTH OF THE FORECAST AREA AROUND DARK. THE FRONT WILL MOVE THROUGH SLOWLY. THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT CLEAR CUT. A BATCH OF SHOWERS AND THUNDERSTORMS OVER NORTHWEST INDIANA WILL DECREASE AS THEY MOVE EAST...SOME SHOWERS COULD GET INTO NW OHIO AFTER DAYBREAK AND THEN CONTINUE TO WEAKEN AS THEY MOVE EAST. GOING ALONG WITH THE HRRR MODEL IN DEVELOPING SHOWERS AND THUNDERSTORMS EARLY IN THE AFTERNOON. MVFR OR IFR VISIBILITIES IN THE HEAVIER STORMS. OUTLOOK...NON VFR IN AREAS OF FOG WEDNESDAY MORNING. && .MARINE... A WEAK COLD FRONT WILL BE MOVING ACROSS LAKE ERIE FROM THE NORTH TODAY. SOME THUNDERSTORMS COULD OCCUR OVER THE LAKE...IT IS POSSIBLE THAT SOME OF THEM COULD PROMPT THE NEED FOR A SPECIAL MARINE WARNING. OTHERWISE BEHIND THE FRONT THE WINDS WILL BE FROM A NORTHERLY DIRECTION AS HIGH PRESSURE BUILDS IN FROM THE NORTHWEST. THE HIGH WILL SHIFT EAST OF LAKE ERIE FOR THE WEEKEND WITH THE WINDS BECOMING SOUTHERLY. IN THE MEANTIME NOT EXPECTING THE WINDS TO BE STRONG ENOUGH TO CAUSE 3 TO 5 FOOT WAVES...BUT THIS WILL HAVE TO BE MONITORED AS THAT DIRECTION CAN BE TRICKY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...ADAMS NEAR TERM...ADAMS SHORT TERM...ADAMS LONG TERM...KIELTYKA AVIATION...KIELTYKA MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
153 AM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT WILL PUSH ACROSS THE AREA TUESDAY. HIGH PRESSURE WILL PUSH SOUTHEAST OVER THE AREA BY THURSDAY...AND REMAIN OVER THE AREA INTO THE WEEKEND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... COLD FRONT CURRENTLY INTO CENTRAL MICHIGAN. DRY FOR A MAJORITY IF NOT ALL OF THE NIGHT...BUT ISOLATED/SCATTERED TSRA MAY BE NEARING TOLEDO AND THE LAKE NEAR 6 AM. WITH CLOUDS MOVING OVER THE AREA AHEAD OF CONVECTION EXPECT OVERNIGHT LOWS WARMER THAN LAST NIGHT. LEANED TOWARD THE SLIGHTLY WARMER METMOS. ADJUSTED THE HOURLY TEMPERATURES FOR THE REMINDER OF THE NIGHT WITH THIS EVENING UPDATE. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... MODELS IN REASONABLE AGREEMENT MOVING THE COLD FRONT ACROSS THE FORECAST AREA TUESDAY INTO TUESDAY NIGHT...REACHING THE OHIO DURING THE DAY ON WEDNESDAY. COULD WELL BE A LULL IN CONVECTION TUESDAY NIGHT WITH A SECOND ROUND OF CONVECTION ON WEDNESDAY AS A SHORT WAVE MOVES ACROSS THE FORECAST AREA. UNFORTUNATELY MODELS NOT IN GOOD AGREEMENT ON EXACT TRACK AND TIMING OF SHORT WAVE. SO FOR NOW WILL JUST CONTINUE WITH CHANCE POPS WEDNESDAY. MODELS ALSO IN GOOD AGREEMENT WITH LARGE AREA OF CANADIAN HIGH PRESSURE CENTERED OVER THE CENTRAL LAKES BY DAYBREAK THURSDAY. TREND AFTER THAT IS A RETURN OF DRIER AND COOLER CONDITIONS. && .LONG TERM /FRIDAY THROUGH MONDAY/... HIGH PRESSURE WILL SETTLE INTO SOUTHERN ONTARIO FOR THE LONG TERM FORECAST PERIOD. THIS WILL KEEP LOW PRESSURE NEAR OR SOUTH OF THE OHIO RIVER WHICH MEANS DRY WEATHER THROUGH THE PERIOD. HIGHS WILL REMAIN NEAR SEASONAL AVERAGES THAT ARE AROUND 80 DEGREES. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... A WEAK COLD FRONT WILL BE MOVING FROM NORTH TO SOUTH TODAY...THE FRONT SHOULD BE SOUTH OF THE FORECAST AREA AROUND DARK. THE FRONT WILL MOVE THROUGH SLOWLY. THE TIMING OF THE SHOWERS AND THUNDERSTORMS IS NOT CLEAR CUT. A BATCH OF SHOWERS AND THUNDERSTORMS OVER NORTHWEST INDIANA WILL DECREASE AS THEY MOVE EAST...SOME SHOWERS COULD GET INTO NW OHIO AFTER DAYBREAK AND THEN CONTINUE TO WEAKEN AS THEY MOVE EAST. GOING ALONG WITH THE HRRR MODEL IN DEVELOPING SHOWERS AND THUNDERSTORMS EARLY IN THE AFTERNOON. MVFR OR IFR VISIBILITIES IN THE HEAVIER STORMS. OUTLOOK...NON VFR IN AREAS OF FOG WEDNESDAY MORNING. && .MARINE... A WEAK COLD FRONT WILL CROSS LAKE ERIE ON TUESDAY WITH HIGH PRESSURE GRADUALLY BUILDING ACROSS THE LAKE INTO THURSDAY. THE HIGH WILL THEN TAKE UP RESIDENCE OVER SOUTHERN ONTARIO FOR THE WEEKEND. SO AFTER A BRIEF PERIOD OF NORTHWESTERLY WINDS THEY WILL SWING AROUND TO THE NORTH AND NORTHEAST FOR THE END OF THE WEEK INTO THE WEEKEND. WINDS WILL REMAIN LIGHT 10 KNOTS OR LESS THROUGH THE FORECAST. THE NORTHWEST WINDS TUESDAY AFTERNOON INTO WEDNESDAY MAY BRIEF BRING WAVES INTO THE 2 TO 3 FOOT RANGE. OTHERWISE 2 FEET OR LESS WILL BE EXPECTED. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...DJB NEAR TERM...DJB/OUDEMAN SHORT TERM...DJB LONG TERM...MULLEN AVIATION...KIELTYKA MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
811 PM EDT WED AUG 6 2014 .SYNOPSIS... A COLD FRONT WILL SETTLE THROUGH THE AREA TODAY. COOLER AND LESS HUMID CONDITIONS WILL OVERSPREAD THE STATE TONIGHT...AND LAST INTO THIS COMING WEEKEND. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... ONLY A LONE SHOWER LEFT. NICE LINE OF TCU OUTSIDE THE OFFICE. ANOTHER UPDATE SENT. EARLIER DISCUSSION BELOW. UPDATED PACKAGE AT 6 PM...TO TAKE OUT SHOWERS AND STORMS EXCEPT FOR AREAS ACROSS THE NE PART OF CENTRAL PA. STILL LOOKING OVER DATA ETC...WILL DO MORE UPDATES AS NEEDED. AFT DISCUSSION BELOW. RUC SHOWS CAPES IN THE 500-1500J RANGE...ALONG WITH THE APPROACH OF A POTENT JET STREAK...WE ARE SEEING RADAR GETTING MORE ACTIVE AS CONVECTION BEGINS TO POP IN THE INCREASINGLY UNSTABLE AIRMASS. LATEST HRRR SHOWS POPCORN RANDOM SHOWERS AND STORMS THROUGH MID AFTERNOON...WITH ACTIVITY BEGINNING TO FADE RAPIDLY AFTER ABOUT 21Z. SHOULD LEAD TO A FINE MID SUMMER EVENING IN MOST LOCATIONS AS DRIER AIR WORKS IN FROM THE NORTH. THE OVERNIGHT WILL BE COOL AND DRY...RANGING FROM THE MID 40S OVER THE NORTH TO THE MID 50S OVER THE SOUTH. THIS WILL BE ABOUT 5-10 DEG BELOW NORMAL. A WEAK GRADIENT LATER TONIGHT WILL LEAD TO AT LEAST SOME PATCHY FOG LATER AFTER MIDNIGHT. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... HIGH PRESSURE BUILDING OUT OF THE GR LAKES WILL BRING THE FIRST OF SEVERAL FINE MID SUMMER DAYS TO THE AREA THURSDAY. THE ECMWF/GFS HINT AT A WEAK SPOKE OF VORTICITY SWINGING DOWN AROUND THE NERN UPPER TROUGH BRINGING SOME LIGHT SHOWERS TO FAR NERN AREAS DURING THE AFTERNOON. THE GEFS DOESN`T SUPPORT THIS AND WITH UPPER HEIGHTS CONTINUING TO BE FORECAST TO RISE...I DECIDED TO DOWNPLAY THE ALREADY SMALL POPS. I WOUDN`T RULE OUT A STRAY SHOWER OR SPRINKLE...BUT I OPTED FOR THE MORE OPTIMISTIC WORDING FOR THE FORECAST...LEAVING OUT THE MENTION OF PRECIP. HIGHS WILL BE VERY PLEASANT IN THE 70S TO LOWER 80S...STILL A TAD BELOW NORMAL FOR EARLY AUGUST. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... FOLLOWING BRIEF DEAMPLIFICATION BEHIND THE SEASONABLY STRONG UPPER LEVEL TROUGH EXITING THE NEW ENGLAND STATES AND THE CANADIAN MARITIMES...THE MEDIUM RANGE FCST WILL FEATURE A RETURN OF THE FAMILIAR WRN RIDGE/ERN NOAM TROUGH PATTERN THAT HAS PREVAILED FOR MOST OF THE SUMMER. AMPLIFICATION OF SERN CANADA SHORTWAVE TROUGH INTO THE ERN U.S. LATE-PERIOD SHOULD SUPPORT A SEWD PUSH OF A COLD FRONT INITIALLY OVER THE NRN PLAINS...EVENTUALLY HELPING TO DISPLACE A QSTRNY FRONT EXTENDING FROM THE PLAINS THROUGH THE S-CENTRAL APPLCHNS AND INTO THE SOUTHEAST. THE 06/12Z OPERATIONAL MODELS AND ENSEMBLES CONTINUE TO SHOW VARIABILITY IN THE PLACEMENT OF MAIN PCPN AXIS ASSOCD WITH ONE OR MORE WAVES MOVG ALONG THE WAVY BOUNDARY. A CONSENSUS BLEND STILL FAVORS AREAS TO THE SOUTH OF CENTRAL PA /VA INTO THE CAROLINAS/ WHERE THE BEST MSTR/PWS WILL RESIDE - ALTHOUGH WILL CONTINUE LOW POPS IN THE FAR SWRN/SCNTRL ZONES THIS WEEKEND AS THIS AREA WILL BE VULNERABLE ON THE NRN EDGE OF MSTR GRADIENT/DEVELOPING SELY LLVL UPSLOPE FLOW. NORTH TO EAST LLVL FLOW TO THE S OF NEW ENGLAND HP SHOULD FAVOR NEAR TO BELOW NORMAL HIGHS AND PERHAPS COOL NIGHTTIME LOWS /ASSUMING CLR SKIES AND ABNORMALLY DRY AIR/. PESKY LOW CLOUDS IN DEVELOPING ESE FLOW MAY ALSO ACT TO TEMPER DAYTIME TEMPS WHILE POTENTIALLY KEEPING THINGS WARMER AT NIGHT. OVERALL NOT EXPECTING ANY MAJOR WARMING TRENDS. SPREAD BTWN OP GFS/ECMWF REALLY INCREASES INTO THE MIDDLE OF NEXT WEEK...WITH THE GFS MUCH MORE AGGRESSIVE IN RETURNING THE AFOREMENTIONED FRONTAL ZONE NWD WHILE THE ECMWF KEEPS IT SUPPRESSED. WPC SEEMS TO FAVOR ECMWF SOLN WHICH BRINGS A COLD FRONT THRU THE AREA ON WED FOLLOWED BY MODEST COOL DOWN IN ITS WAKE BY LATER NEXT WEEK. CONFIDENCE IS BELOW AVG GIVEN THE COMPLEX PATTERN AND LARGE MODEL SPREAD/DETAIL UNCERTAINTY. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... ALTOONA IS THE LONE HOLDOUT WITH A 2600` CEILING AS OF 2PM...BUT THIS TOO SHOULD RISE AND MIX OUT BEFORE TOO LONG. OTHER THAN A HIT AND MISS SHOWER OR THUNDERSTORM BRINGING BRIEFLY REDUCED CONDITIONS INTO THE EARLY EVENING...CONDITIONS WILL REMAIN VFR INTO THE OVERNIGHT. AS EVENING APPROACHES..SHOWERS AND STORMS WILL BEGIN TO FADE. OTHER THAN SOME PATCHY FOG OVERNIGHT...EXPECT VFR CONDITIONS AS DRIER BEGINS TO MOVE INTO THE REGION. TOMORROW WILL BEGIN A SEVERAL DAY PERIOD OF NON-EVENTFUL WEATHER AND PRIMARILY VFR CONDITIONS. OUTLOOK... THU-SAT...MAINLY VFR. PATCHY FOG/LOW CLOUDS POSSIBLE EARLY. SUN-MON...MAINLY VFR BUT WITH ISOLATED SHOWERS AND THUNDERSTORMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE/MARTIN SHORT TERM...LA CORTE LONG TERM...STEINBUGL AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
322 PM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT WILL PUSH ACROSS THE STATE THIS AFTERNOON AND EVENING. A STRONGER COLD FRONT WILL MOVE THROUGH THE COMMONWEALTH WEDNESDAY FOLLOWED BY COOLER AND LESS HUMID CONDITIONS THAT WILL LAST INTO THIS UPCOMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... DEEP MOISTURE CONVERGENCE AND CAPES IN THE 1000-15000J RANGE OVER NORTHERN PA IS RESULTING IN SHOWERS AND THUNDERSTORMS BREAKING OUT MAINLY NORTH OF I-80. HRRR SEEMS A LITTLE SLOW IN CONVECTIVE INITIATION...BUT SEEMS TO HAVE THE MODE CORRECT AND SUPPORTS THE NEAR TERM IDEA OF KEEPING CONVECTION MAINLY OVER THE NORTHERN HALF OFMY FCST AREA. CROSS SECTIONS THROUGH THE STORMS SHOWS SOME ELEVATED CORES IN SOME OF THE MORE ROBUST UPDRAFTS...MEANING SOME GUSTY WINDS CANNOT BE RULED OUT IN A FEW STORMS. BUT THE OVERALL SEVERE THREAT SHOULD STAY MINIMAL TODAY WITH MOST STORMS BEING PULSE TYPES AND LACKING OVERALL ORGANIZATION. SHOWER ACTIVITY IS EXPECTED TO FADE WITH THE LOSS OF THE SUN AS ALL INDICATORS SHOW INSTABILITY DWINDLING QUICKLY. I KEPT A SMALL MENTION OF PRECIP OVER NORTHERN AREAS EVEN AFTER MIDNIGHT AS THE SECOND STRONGER COLD FRONT TAKES SHAPE AS IT DROPS INTO THE LOWER LAKES LATER TONIGHT. OVERNIGHT LOWS FROM THE MOD 50S TO MID 60S NW TO SE WILL BE VERY NEAR SEASONAL NORMS. && .SHORT TERM /WEDNESDAY/... WEDNESDAY...A VIGOROUS UPPER JET STREAK IS MADE TO DIVE INTO SWRN PA DURING THE AFTERNOON. MODELS GENERATE STRONG SHEAR AND A RESPECTABLE AMOUNT OF CAPE ON AND TO THE LEFT OF THE NOSE OF THIS UPPER JET STREAK. INSTABILITY AS ALWAYS WILL DEPEND ON HOW MUCH SUN WE CAN MANAGE...BUT ISOLATED SEVERE STORMS CANNOT BE RULED OUT FROM MID MORNING INTO THE AFTERNOON HOURS AS THE SECONDARY COLD FRONT SAGS SOUTH. RIGHT NOW WE ARE IN A GENERAL THUNDER OUTLOOK FROM SPC...BUT WOULD NOT BE SURPRISED IF WE ARE ELEVATED TO A SLIGHT RISK GIVEN YET ANOTHER ANOMALOUSLY STRONG SYSTEM MOVING INTO THE AREA. RIGHT NOW I HAVE TEMPS DIALED A NOTCH BELOW TODAY`S READINGS GIVEN THE EXPECTATIONS OF MORE CLOUDS AND SHOWER ACTIVITY. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... QUALITY/REFRESHING LOW PWAT AIRMASS BEING DIRECTED EQUATORWARD VIA NLY FLOW BEHIND REINFORCING COLD FRONT WILL BRING AN END TO SCT SHOWER/TSTM ACTIVITY ACROSS THE SRN TIER ZONES EARLY WED NGT. LG SCALE FORCING ON SW FRINGE OF SLOWLY PROGRESSING MID-UPPER LVL TROUGH MOVG EWD ACRS INTERIOR NEW ENGLAND/NORTHEAST STATES...ALONG WITH ACCOMPANYING PLUME OF RELATIVELY STEEP MID-LVL LAPSE RATES NEAR 6 C/KM ASSOCD WITH -15C AT 500MB AND ANOMALOUS H7 TEMPS MAY INITIATE A FEW INSTABILITY SHOWERS OVER NRN-NERN SXNS ON THU. GRIDDED SKY COVER MAY NEED TO BE ADJUSTED UPWARD AS THE SET-UP APPEARS FAVORABLE FOR AT LEAST A BKN CU FIELD TO DVLP BY AFTN. OTHERWISE..EXPECT A RATHER PLEASANT DAY WITH COMFORTABLE HUMIDITY AND 5-10KT NNW WIND. SHORTWAVE RIDGING AND 500MB HEIGHT RISES SHOULD GRADUALLY REPLACE THE DEPARTING UPPER TROUGH/CYC FLOW ALOFT OVER THE REGION FRI- SUN. AT THE SFC...HIGH PRESSURE MIGRATING S/SEWD FROM THE UPPER GRT LKS/SERN CANADA SHOULD PROVIDE A STRING OF DRY WX WITH PLEASANT DAYS AND RELATIVELY COOL NGTS. 05/12Z MODELS ARE IN DECENT AGREEMENT IN KEEPING THE MAIN AXIS OF PCPN SOUTH OF PA ALONG A NW/SE ORIENTED FRONTAL ZONE/INVERTED TROUGH AXIS LOCATED FROM THE MID MO/LWR OH VLYS INTO THE SRN/CNTRL APPLCHNS AND SRN MID-ATLC/SE STATES. THE PCPN PATTERN SHOULD BECOME MORE UNSETTLED INTO THE MIDDLE OF NEXT WEEK WITH INCR MSTR/SLY WINDS CONSISTENT WITH RETURN FLOW ON BACKSIDE OF DEPARTING HP...WITH A FRONTAL SYSTEM APPROACHING THE AREA FROM THE NW. CONSENSUS BLEND OF THE LATEST OPERATIONAL AND ENSEMBLE GUIDANCE FAVORS NEAR TO SLIGHTLY BELOW NORMAL TEMPS DURING THE PERIOD. && .AVIATION /19Z TUESDAY THROUGH SUNDAY/... ALL TERMINALS ARE VFR AND THIS WILL CONTINUE INTO THE EVENING. EXCEPTIONS WILL BE WHERE DEVELOPING CONVECTION WANDERS INTO TERMINAL AIRSPACE THROUGH LATE AFTERNOON. THE BEST CHANCE OF THIS WILL BE OVER THE FAR NORTH IN AND AROUND BRADFORD...AND POSSIBLYINTO WILLIAMSPORT AFTER 20Z. SHOWERS AND THUNDERSTORMS WILL TEND TO FADE AS WE LOSE THE SUN. LOCAL MVFR/IFR RESTRICTIONS WILL BECOME POSSIBLE ONCE AGAIN TONIGHT WITH THE FORMATION OF AREAS OF LOW CLOUDS AND FOG. A STRONGER COLD FRONT WILL BRING A BETTER CHANCE OF RESTRICTIONS ASSOCIATED WITH WIDESPREAD SHOWERS AND THUNDERSTORMS WEDNESDAY. DRIER AIR AND IMPROVING CONDITIONS WILL TEND TO WORK IN FROM THE NORTH LATER IN THE DAY. OUTLOOK... THU-SAT...MAINLY VFR. PATCHY FOG/LOW CLOUDS POSSIBLE EARLY. SUN...MAINLY VFR BUT WITH ISOLATED SHOWERS AND THUNDERSTORMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...STEINBUGL AVIATION...LA CORTE/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
222 PM EDT TUE AUG 5 2014 .SYNOPSIS... A WEAK COLD FRONT WILL PUSH ACROSS THE STATE THIS AFTERNOON AND EVENING. A STRONGER COLD FRONT WILL MOVE THROUGH THE COMMONWEALTH WEDNESDAY FOLLOWED BY COOLER AND LESS HUMID CONDITIONS THAT WILL LAST INTO THIS UPCOMING WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... DEEP MOISTURE CONVERGENCE AND CAPES IN THE 1000-15000J RANGE OVER NORTHERN PA IS RESULTING IN SHOWERS AND THUNDERSTORMS BREAKING OUT MAINLY NORTH OF I-80. HRRR SEEMS A LITTLE SLOW IN CONVECTIVE INITIATION...BUT SEEMS TO HAVE THE MODE CORRECT AND SUPPORTS THE NEAR TERM IDEA OF KEEPING CONVECTION MAINLY OVER THE NORTHERN HALFOF MY FCST AREA. CROSS SECTIONS THROUGH THE STORMS SHOWS SOME ELEVATED CORES IN SOME OF THE MORE ROBUST UPDRAFTS...MEANING SOME GUSTY WINDS CANNOT BE RULED OUT IN A FEW STORMS. BUT THE OVERALL SEVERE THREAT SHOULD STAY MINIMAL TODAY WITH MOST STORMS BEING PULSE TYPES AND LACKING OVERALL ORGANIZATION. SHOWER ACTIVITY IS EXPECTED TO FADE WITH THE LOSS OF THE SUN AS ALL INDICATORS SHOW INSTABILITY DWINDLING QUICKLY. I KEPT A SMALL MENTION OF PRECIP OVER NORTHERN AREAS EVEN AFTER MIDNIGHT AS THE SECOND STRONGER COLD FRONT TAKES SHAPE AS IT DROPS INTO THE LOWER LAKES LATER TONIGHT. OVERNIGHT LOWS FROM THE MOD 50S TO MID 60S NW TO SE WILL BE VERY NEAR SEASONAL NORMS. && .SHORT TERM /WEDNESDAY/... WEDNESDAY...A VIGOROUS UPPER JET STREAK IS MADE TO DIVE INTO SWRN PA DURING THE AFTERNOON. MODELS GENERATE STRONG SHEAR AND A RESPECTABLE AMOUNT OF CAPE ON AND TO THE LEFT OF THE NOSE OF THIS UPPER JET STREAK. INSTABILITY AS ALWAYS WILL DEPEND ON HOW MUCH SUN WE CAN MANAGE...BUT ISOLATED SEVERE STORMS CANNOT BE RULED OUT FROM MID MORNING INTO THE AFTERNOON HOURS AS THE SECONDARY COLD FRONT SAGS SOUTH. RIGHT NOW WE ARE IN A GENERAL THUNDER OUTLOOK FROM SPC...BUT WOULD NOT BE SURPRISED IF WE ARE ELEVATED TO A SLIGHT RISK GIVEN YET ANOTHER ANOMALOUSLY STRONG SYSTEM MOVING INTO THE AREA. RIGHT NOW I HAVE TEMPS DIALED A NOTCH BELOW TODAY`S READINGS GIVEN THE EXPECTATIONS OF MORE CLOUDS AND SHOWER ACTIVITY. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... LG SCALE FORCING AND COOLER AIR ALOFT/STEEP MID-LVL LAPSE RATES TIED TO PASSAGE OF UPPER LEVEL TROUGH AXIS MAY PROVIDE ENOUGH LIFT TO GENERATE ISOLD...INSTABILITY TYPE SHOWERS ON THU AFTN. OTHERWISE ANTICIPATE A DRY PERIOD THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK...WITH STRING OF PLEASANT DAYS/COMFORTABLE NIGHTS AS AREA REMAINS UNDER THE INFLUENCE OF SFC HIGH PRES MIGRATING S/SEWD FROM THE UPPER GRT LKS. TEMPS WILL START OUT BELOW AVG BEHIND THE DEPARTING TROUGH AXIS BUT SHOULD MODERATE AS HEIGHTS REBOUND BY 10/11 AUG. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... ALL TERMINALS ARE VFR AND THIS WILL CONTINUE INTO THE EVENING. EXCEPTIONS WILL BE WHERE DEVELOPING CONVECTION WANDERS INTO TERMINAL AIRSPACE THROUGH LATE AFTERNOON. THE BEST CHANCE OF THIS WILL BE OVER THE FAR NORTH IN AND AROUND BRADFORD...AND POSSIBILY INTO WILLIAMSPORT AFTER 20Z. SHOWERS AND THUNDERSTORMS WILL TEND TO FADE AS WE LOSE THE SUN. LOCAL MVFR/IFR RESTRICTIONS WILL BECOME POSSIBLE ONCE AGAIN TONIGHT WITH THE FORMATION OF AREAS OF LOW CLOUDS AND FOG. A STRONGER COLD FRONT WILL BRING A BETTER CHANCE OF RESTRICTIONS ASSOCIATED WITH WIDESPREAD SHOWERS AND THUNDERSTORMS WEDNESDAY. DRIER AIR AND IMPROVING CONDITIONS WILL TEND TO WORK IN FROM THE NORTH LATER IN THE DAY. OUTLOOK... THU-SAT...MAINLY VFR. PATCHY FOG/LOW CLOUDS POSSIBLE EARLY. SUN...MAINLY VFR BUT WITH ISOLATED SHOWERS AND THUNDERSTORMS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...LA CORTE SHORT TERM...LA CORTE LONG TERM...LAMBERT/STEINBUGL AVIATION...LA CORTE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1045 AM EDT TUE AUG 5 2014 .SYNOPSIS... A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE STATE THIS AFTERNOON AND EVENING. A STRONGER COLD FRONT WILL MOVE THROUGH THE COMMONWEALTH WEDNESDAY FOLLOWED BY COOLER AND LESS HUMID CONDITIONS THAT WILL FOLLOW FOR LATE WEDNESDAY INTO THIS UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... EARLY MORNING FOG HAS PRETTY MUCH DISSIPATED LEAVING MOST OF THE REGION BRIGHT AND SUNNY...ALBEIT SOMEWHAT HAZY. CLOUDS ARE ENCROACHING OVER THE NW ASSOCIATED WITH A WEAK COLD FRONT THAT IS MOVING INTO CENTRAL OHIO. THIS WILL BRING INCREASING CHANCES FOR CONVECTION TODAY...ESPECIALLY OVER THE NWRN THIRD TO HALF OF THE FCST AREA. MODELS SHOW SOME MODERATE INSTABILITY DEVELOPING TODAY BUT WINDS ARE EXPECTED TO REMAIN WEAK SO SEVERE THREAT SHOULD BE MINIMAL. THE LATEST HRRR AND WRF ARW WERE BLENDED WITH THE 03Z SREF TO PAINT TIMING AND AREAL COVERAGE DETAILS INTO OUR POP AND WEATHER GRID DATABASE FOR THE ANTICIPATED SHOWERS AND SCATTERED TSRA THAT WILL IMPACT MAINLY THE NW HALF OF THE CWA DURING THE MIDDAY AND AFTERNOON HOURS TODAY. THE FRONTAL BOUNDARY WILL GRADUALLY WEAKEN AND SLOW AS IT EDGES TWD THE LAURELS AND LOWER SUSQ VALLEY TONIGHT...WITH ISOLATED TO WIDELY SCATTERED TSRA DRIFTING INTO THAT REGION LATER THIS EVENING. BASIN AVERAGE RAINFALL ENDING AT 00Z WED RANGE FROM ONE- TENTH...TO ONE-QUARTER OF AN INCH ACROSS THE NRN MTNS...TO JUST A FEW HUNDREDTHS AT BEST IN THE FAR SE. CONSENSUS BLEND OF ALL MODEL GUIDANCE YIELDS A HIGH TEMP IN THE MID TO UPPER 70S ACROSS THE NRN MTNS AND LAUREL HIGHLANDS...AND MID TO UPPER 80S THROUGHOUT THE VALLEYS OF CENTRAL AND SERN PENN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... THE SCATTERED SHRA/TSRA LATE THIS AFTERNOON/EVENING ASSOCIATED WITH A WEAK COLD FRONT /AND PRE-FRONTAL TROUGH/ SHOULD DECREASE IN CVRG TONIGHT INTO EARLY WED WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. CONCERNED THAT THE APPROACH OF A STRONG /90 KT/ 300 MB JET AND INCREASING DEEP LAYER UVVEL/STRONG PVA ASSOCIATED WITH THE THERMALLY INDIRECT TRANSVERSE CIRCULATION OF ITS LEFT EXIT REGION WILL SPARK A SEVERAL TO 6-HOUR PERIOD OF MORE NUMEROUS SHOWERS AND TSRA PRECEDING A SECONDARY CFRONT VERY EARLY WED ACROSS THE FAR WEST...AND DURING THE MID MORNING THROUGH MID AFTERNOON HOURS ACROSS THE CENTRAL AND SE ZONES. THE POTENTIAL FEW ROUNDS OF SHOWERS AND TSRA ALONG AND AHEAD OF THIS SECONDARY CFRONT SHOULD BE THE LAST DECENT OPPORTUNITY FOR RAINFALL HERE IN CENTRAL PA FOR AT LEAST 2-3 DAYS. 0-3 KM BULK SHEAR DOES HOWEVER INCREASED TO 25-30 KTS FROM THE WEST TO SOUTHWEST WEDNESDAY...WITH 0-6KM BULK SHEAR OF 40-45 KTS ACROSS NRN PENN IN THE MORNING...AND A RIBBON OF 50-60 KT SHEAR ACRS SOUTHERN PENN LATE WED AFTERNOON. HOWEVER... THE DY2 SPC CONVECTIVE OUTLOOK CONTINUES TO INDICATE ONLY FOR GENERAL THUNDER...WITH THE STG-SVR STORM THREAT LIMITED BY THE APPARENT LACK OF DEEP LYR MSTR/AVG PWS AND CAPE. WOULDN/T BE SURPRISED TO SEE THIS INCREASED TO A SEE TEXT /OR EVEN A COMPACT SLIGHT RISK AREA ACROSS PENN/ WITH LATER UPDATES. STRONG SUBSIDENCE BENEATH THE LEFT ENTRANCE REGION OF THE JET WILL LEAD TO CLEARING AND A RELATIVE MIN OF PRECIP ACROSS THE NRN THIRD TO HALF OF THE STATE AFTER 21Z WED...WHILE ISOLATED TO SCATTERED SHRA/TSRA LINGER ACROSS THE SOUTH. LOW TEMPS TONIGHT UNDER A FAIR AMOUNT OF CLOUD COVER /50-70 PERCENT/ WILL BE IN THE MID 50S TO MID 60S...WITH HIGH TEMPS WEDNESDAY VARYING FROM THE LOWER 70S ACROSS THE NRN MTNS...TO THE LOWER 80S IN THE SE. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... LG SCALE FORCING AND COOLER AIR ALOFT/STEEP MID-LVL LAPSE RATES TIED TO PASSAGE OF UPPER LEVEL TROUGH AXIS MAY PROVIDE ENOUGH LIFT TO GENERATE ISOLD...INSTABILITY TYPE SHOWERS ON THU AFTN. OTHERWISE ANTICIPATE A DRY PERIOD THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK...WITH STRING OF PLEASANT DAYS/COMFORTABLE NIGHTS AS AREA REMAINS UNDER THE INFLUENCE OF SFC HIGH PRES MIGRATING S/SEWD FROM THE UPPER GRT LKS. TEMPS WILL START OUT BELOW AVG BEHIND THE DEPARTING TROUGH AXIS BUT SHOULD MODERATE AS HEIGHTS REBOUND BY 10/11 AUG. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... ALL TERMINALS ARE VFR AS OF 10AM WITH THE EXCEPTION OF SOME LINGERING LOW CLOUDS AND HAZE AT WILLIAMSPORT AND SELINSGROVE. ALL SITES WILL BE VFR BY MID DAY AND THIS WILL CONTINUE INTO THE AFTERNOON. FOR TODAY...CLOUDS WILL REMAIN FEW TO SCATTERED IN THE SE HALF OF CWA...BUT A WEAK FRONTAL SYSTEM SLIDING INTO THE NW WILL BRING LOCAL REDUCTIONS IN SCATTERED AFTERNOON SHOWERS AND TSTMS. WINDS WILL REMAIN LIGHT EXCEPT IN THE THUNDERSTORMS. SCT MVFR RESTRICTIONS WILL BE POSSIBLE AGAIN TONIGHT ALONG WITH LINGERING CHANCES FOR SHOWERS MAINLY ACROSS THE NORTHWEST. SCT SHOWERS AND TSTMS WILL ONCE AGAIN RETURN FOR WEDNESDAY WITH A SECONDARY STRONGER COLD FRONT. OUTLOOK... TUE...SCATTERED SHRA/TSRA WITH APPROACHING COLD FRONT...MAINLY NW. WED...SCATTERED SHRA/TSRA. THU-SAT...MAINLY VFR. PATCHY FOG POSSIBLE EARLY. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE/LAMBERT NEAR TERM...LA CORTE/LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/STEINBUGL AVIATION...LA CORTE/RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
749 AM EDT TUE AUG 5 2014 .SYNOPSIS... A RIDGE OF HIGH PRESSURE AND RELATIVELY DRY AIR WILL COVER CENTRAL AND SOUTHEASTERN PENNSYLVANIA THIS MORNING. A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE STATE THIS AFTERNOON AND EVENING. A SURGE OF COOLER...DRIER AIR AND SHARPENING OF THE UPPER TROUGH WILL PUSH A STRONGER COLD FRONT ACROSS THE COMMONWEALTH WEDNESDAY. COMFORTABLE HUMIDITY AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES WILL FOLLOW FOR LATE WEDNESDAY INTO THIS UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SURFACE HIGH PRESSURE RIDGE STRETCHED SW TO NE ACROSS THE CWA WILL MAINTAIN CLEAR SKIES AND NEARLY CALM AIR FOR THE REST OF THE OVERNIGHT HOURS. THE CURRENT TIGHT...ZERO - 3 DEG F TEMP/DEWPOINT SPREAD AND AN AIR TO RIVER/STREAM TEMP DIFF OF AROUND 20F WILL LEAD TO PATCHY VALLEY FOG FOR SEVERAL HOURS LEADING UP TO...AND SHORTLY AFTER SUNRISE. VSBYS IN THE DEEPEST/COOLEST VALLEYS OF NRN PENN COULD DIP BRIEFLY BELOW 1/4SM THROUGH 12Z. LOW TEMPS THIS MORNING WILL RANGE FROM THE MID 50S IN THE COOLER NORTHERN AND WESTERN MTN VALLEYS...TO THE LOWER 60S IN THE SOUTHEAST METRO AREAS. QUASI-STNRY/RELATIVELY WEAK SFC FRONT EXTENDED FROM GRAND RAPIDS MICHIGAN...TO NEAR THE NORTH SHORE OF LAKE ERIE AT 08Z. ABUNDANT SUNSHINE WILL OCCUR THIS MORNING ACROSS THE LAUREL HIGHLANDS...CENTRAL MTNS...LYCOMING VALLEY AND NCENT MTNS BEFORE CLOUDS AND SCATTERED SHRA/TSRA ENCROACH FROM THE NW THIS AFTERNOON. THE LOWER SUSQ VALLEY SHOULD BASK IN MOSTLY SUNNY CONDITIONS WITH RELATIVELY COMFORTABLE HUMIDITY...THANKS TO THE SFC RIDGE AND NEAR TO SLIGHTLY BELOW NORMAL PWAT LINGERING THERE UNTIL 00Z WED. THE LATEST HRRR AND WRF ARW WERE BLENDED WITH THE 03Z SREF TO PAINT TIMING AND AREAL COVERAGE DETAILS INTO OUR POP AND WEATHER GRID DATABASE FOR THE ANTICIPATED SHOWERS AND SCATTERED TSRA THAT WILL IMPACT MAINLY THE NW HALF OF THE CWA DURING THE MIDDAY AND AFTERNOON HOURS TODAY. THE FRONTAL BOUNDARY WILL GRADUALLY WEAKEN AND SLOW AS IT EDGES TWD THE LAURELS AND LOWER SUSQ VALLEY TONIGHT...WITH ISOLATED TO WIDELY SCATTERED TSRA DRIFTING INTO THAT REGION LATER THIS EVENING. MU CAPES WILL INCREASE TO BETWEEN 800-1200 J/KG IN MOST PLACES BETWEEN 16-20Z...WITH A POCKET OF 1500 J/KG CAPE PRECEDING THE AREA OF MOST NUMEROUS SHRA/TSRA ACROSS THE NW AND NCENT MTNS LATE THIS AFTERNOON AND EARLY THIS EVENING. BASIN AVERAGE RAINFALL ENDING AT 00Z WED RANGE FROM ONE-TENTH...TO ONE-QUARTER OF AN INCH ACROSS THE NRN MTNS...TO JUST A FEW HUNDREDTHS AT BEST IN THE FAR SE. CONSENSUS BLEND OF ALL MODEL GUIDANCE YIELDS A HIGH TEMP IN THE MID TO UPPER 70S ACROSS THE NRN MTNS AND LAUREL HIGHLANDS...AND MID TO UPPER 80S THROUGHOUT THE VALLEYS OF CENTRAL AND SERN PENN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... THE SCATTERED SHRA/TSRA LATE THIS AFTERNOON/EVENING ASSOCIATED WITH A WEAK COLD FRONT /AND PRE-FRONTAL TROUGH/ SHOULD DECREASE IN CVRG TONIGHT INTO EARLY WED WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. CONCERNED THAT THE APPROACH OF A STRONG /90 KT/ 300 MB JET AND INCREASING DEEP LAYER UVVEL/STRONG PVA ASSOCIATED WITH THE THERMALLY INDIRECT TRANSVERSE CIRCULATION OF ITS LEFT EXIT REGION WILL SPARK A SEVERAL TO 6-HOUR PERIOD OF MORE NUMEROUS SHOWERS AND TSRA PRECEDING A SECONDARY CFRONT VERY EARLY WED ACROSS THE FAR WEST...AND DURING THE MID MORNING THROUGH MID AFTERNOON HOURS ACROSS THE CENTRAL AND SE ZONES. THE POTENTIAL FEW ROUNDS OF SHOWERS AND TSRA ALONG AND AHEAD OF THIS SECONDARY CFRONT SHOULD BE THE LAST DECENT OPPORTUNITY FOR RAINFALL HERE IN CENTRAL PA FOR AT LEAST 2-3 DAYS. 0-3 KM BULK SHEAR DOES HOWEVER INCREASED TO 25-30 KTS FROM THE WEST TO SOUTHWEST WEDNESDAY...WITH 0-6KM BULK SHEAR OF 40-45 KTS ACROSS NRN PENN IN THE MORNING...AND A RIBBON OF 50-60 KT SHEAR ACRS SOUTHERN PENN LATE WED AFTERNOON. HOWEVER... THE DY2 SPC CONVECTIVE OUTLOOK CONTINUES TO INDICATE ONLY FOR GENERAL THUNDER...WITH THE STG-SVR STORM THREAT LIMITED BY THE APPARENT LACK OF DEEP LYR MSTR/AVG PWS AND CAPE. WOULDN/T BE SURPRISED TO SEE THIS INCREASED TO A SEE TEXT /OR EVEN A COMPACT SLIGHT RISK AREA ACROSS PENN/ WITH LATER UPDATES. STRONG SUBSIDENCE BENEATH THE LEFT ENTRANCE REGION OF THE JET WILL LEAD TO CLEARING AND A RELATIVE MIN OF PRECIP ACROSS THE NRN THIRD TO HALF OF THE STATE AFTER 21Z WED...WHILE ISOLATED TO SCATTERED SHRA/TSRA LINGER ACROSS THE SOUTH. LOW TEMPS TONIGHT UNDER A FAIR AMOUNT OF CLOUD COVER /50-70 PERCENT/ WILL BE IN THE MID 50S TO MID 60S...WITH HIGH TEMPS WEDNESDAY VARYING FROM THE LOWER 70S ACROSS THE NRN MTNS...TO THE LOWER 80S IN THE SE. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... LG SCALE FORCING AND COOLER AIR ALOFT/STEEP MID-LVL LAPSE RATES TIED TO PASSAGE OF UPPER LEVEL TROUGH AXIS MAY PROVIDE ENOUGH LIFT TO GENERATE ISOLD...INSTABILITY TYPE SHOWERS ON THU AFTN. OTHERWISE ANTICIPATE A DRY PERIOD THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK...WITH STRING OF PLEASANT DAYS/COMFORTABLE NIGHTS AS AREA REMAINS UNDER THE INFLUENCE OF SFC HIGH PRES MIGRATING S/SEWD FROM THE UPPER GRT LKS. TEMPS WILL START OUT BELOW AVG BEHIND THE DEPARTING TROUGH AXIS BUT SHOULD MODERATE AS HEIGHTS REBOUND BY 10/11 AUG. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... THE AREAS OF FOG THIS MORNING ALREADY SHOWING SIGNS OF IMPROVEMENT BY 12Z...WITH A RETURN TO VFR FOR ALL TERMINALS BY 13-14Z. FOG MAY PERSIST THE LONGEST AT KIPT WITH THICKEST FOG SETTLED IN THE WIDE RIVER VALLEY THERE. FOR TODAY...CLOUDS WILL REMAIN FEW TO SCATTERED IN THE SE HALF OF CWA...BUT A WEAK FRONTAL SYSTEM SLIDING INTO THE NW WILL BRING LOCAL MVFR CONDITIONS IN SCATTERED TO NUMEROUS MID/LATE AFTERNOON SHOWERS/ISO TSTMS AROUND KBFD. ISOLATED CONVECTION POSS FROM KJST-KUNV-KIPT...BUT POPS TOO LOW TO MENTION IN TAFS. WINDS WILL REMAIN LIGHT. SCT MVFR RESTRICTIONS POSS AGAIN TONIGHT ALONG WITH LINGERING CHANCE FOR SHOWERS /MAINLY ACROSS THE NORTHWEST/. SCT SHOWERS AND TSTMS RETURN AREAWIDE FOR WED. OUTLOOK... TUE...SCATTERED SHRA/TSRA WITH APPROACHING COLD FRONT...MAINLY NW. WED...SCATTERED SHRA/TSRA. THU-SAT...MAINLY VFR. PATCHY FOG POSSIBLE EARLY. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/STEINBUGL AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
514 AM EDT TUE AUG 5 2014 .SYNOPSIS... A RIDGE OF HIGH PRESSURE AND RELATIVELY DRY AIR WILL COVER CENTRAL AND SOUTHEASTERN PENNSYLVANIA THIS MORNING. A COLD FRONT WILL PUSH SOUTHEAST ACROSS THE STATE THIS AFTERNOON AND EVENING. A SURGE OF COOLER...DRIER AIR AND SHARPENING OF THE UPPER TROUGH WILL PUSH A STRONGER COLD FRONT ACROSS THE COMMONWEALTH WEDNESDAY. COMFORTABLE HUMIDITY AND NEAR TO SLIGHTLY BELOW NORMAL TEMPERATURES WILL FOLLOW FOR LATE WEDNESDAY INTO THIS UPCOMING WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SURFACE HIGH PRESSURE RIDGE STRETCHED SW TO NE ACROSS THE CWA WILL MAINTAIN CLEAR SKIES AND NEARLY CALM AIR FOR THE REST OF THE OVERNIGHT HOURS. THE CURRENT TIGHT...ZERO - 3 DEG F TEMP/DEWPOINT SPREAD AND AN AIR TO RIVER/STREAM TEMP DIFF OF AROUND 20F WILL LEAD TO PATCHY VALLEY FOG FOR SEVERAL HOURS LEADING UP TO...AND SHORTLY AFTER SUNRISE. VSBYS IN THE DEEPEST/COOLEST VALLEYS OF NRN PENN COULD DIP BRIEFLY BELOW 1/4SM THROUGH 12Z. LOW TEMPS THIS MORNING WILL RANGE FROM THE MID 50S IN THE COOLER NORTHERN AND WESTERN MTN VALLEYS...TO THE LOWER 60S IN THE SOUTHEAST METRO AREAS. QUASI-STNRY/RELATIVELY WEAK SFC FRONT EXTENDED FROM GRAND RAPIDS MICHIGAN...TO NEAR THE NORTH SHORE OF LAKE ERIE AT 08Z. ABUNDANT SUNSHINE WILL OCCUR THIS MORNING ACROSS THE LAUREL HIGHLANDS...CENTRAL MTNS...LYCOMING VALLEY AND NCENT MTNS BEFORE CLOUDS AND SCATTERED SHRA/TSRA ENCROACH FROM THE NW THIS AFTERNOON. THE LOWER SUSQ VALLEY SHOULD BASK IN MOSTLY SUNNY CONDITIONS WITH RELATIVELY COMFORTABLE HUMIDITY...THANKS TO THE SFC RIDGE AND NEAR TO SLIGHTLY BELOW NORMAL PWAT LINGERING THERE UNTIL 00Z WED. THE LATEST HRRR AND WRF ARW WERE BLENDED WITH THE 03Z SREF TO PAINT TIMING AND AREAL COVERAGE DETAILS INTO OUR POP AND WEATHER GRID DATABASE FOR THE ANTICIPATED SHOWERS AND SCATTERED TSRA THAT WILL IMPACT MAINLY THE NW HALF OF THE CWA DURING THE MIDDAY AND AFTERNOON HOURS TODAY. THE FRONTAL BOUNDARY WILL GRADUALLY WEAKEN AND SLOW AS IT EDGES TWD THE LAURELS AND LOWER SUSQ VALLEY TONIGHT...WITH ISOLATED TO WIDELY SCATTERED TSRA DRIFTING INTO THAT REGION LATER THIS EVENING. MU CAPES WILL INCREASE TO BETWEEN 800-1200 J/KG IN MOST PLACES BETWEEN 16-20Z...WITH A POCKET OF 1500 J/KG CAPE PRECEDING THE AREA OF MOST NUMEROUS SHRA/TSRA ACROSS THE NW AND NCENT MTNS LATE THIS AFTERNOON AND EARLY THIS EVENING. BASIN AVERAGE RAINFALL ENDING AT 00Z WED RANGE FROM ONE-TENTH...TO ONE-QUARTER OF AN INCH ACROSS THE NRN MTNS...TO JUST A FEW HUNDREDTHS AT BEST IN THE FAR SE. CONSENSUS BLEND OF ALL MODEL GUIDANCE YIELDS A HIGH TEMP IN THE MID TO UPPER 70S ACROSS THE NRN MTNS AND LAUREL HIGHLANDS...AND MID TO UPPER 80S THROUGHOUT THE VALLEYS OF CENTRAL AND SERN PENN. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... THE SCATTERED SHRA/TSRA LATE THIS AFTERNOON/EVENING ASSOCIATED WITH A WEAK COLD FRONT /AND PRE-FRONTAL TROUGH/ SHOULD DECREASE IN CVRG TONIGHT INTO EARLY WED WITH THE LOSS OF DAYTIME HEATING/INSTABILITY. CONCERNED THAT THE APPROACH OF A STRONG /90 KT/ 300 MB JET AND INCREASING DEEP LAYER UVVEL/STRONG PVA ASSOCIATED WITH THE THERMALLY INDIRECT TRANSVERSE CIRCULATION OF ITS LEFT EXIT REGION WILL SPARK A SEVERAL TO 6-HOUR PERIOD OF MORE NUMEROUS SHOWERS AND TSRA PRECEDING A SECONDARY CFRONT VERY EARLY WED ACROSS THE FAR WEST...AND DURING THE MID MORNING THROUGH MID AFTERNOON HOURS ACROSS THE CENTRAL AND SE ZONES. THE POTENTIAL FEW ROUNDS OF SHOWERS AND TSRA ALONG AND AHEAD OF THIS SECONDARY CFRONT SHOULD BE THE LAST DECENT OPPORTUNITY FOR RAINFALL HERE IN CENTRAL PA FOR AT LEAST 2-3 DAYS. 0-3 KM BULK SHEAR DOES HOWEVER INCREASED TO 25-30 KTS FROM THE WEST TO SOUTHWEST WEDNESDAY...WITH 0-6KM BULK SHEAR OF 40-45 KTS ACROSS NRN PENN IN THE MORNING...AND A RIBBON OF 50-60 KT SHEAR ACRS SOUTHERN PENN LATE WED AFTERNOON. HOWEVER... THE DY2 SPC CONVECTIVE OUTLOOK CONTINUES TO INDICATE ONLY FOR GENERAL THUNDER...WITH THE STG-SVR STORM THREAT LIMITED BY THE APPARENT LACK OF DEEP LYR MSTR/AVG PWS AND CAPE. WOULDN/T BE SURPRISED TO SEE THIS INCREASED TO A SEE TEXT /OR EVEN A COMPACT SLIGHT RISK AREA ACROSS PENN/ WITH LATER UPDATES. STRONG SUBSIDENCE BENEATH THE LEFT ENTRANCE REGION OF THE JET WILL LEAD TO CLEARING AND A RELATIVE MIN OF PRECIP ACROSS THE NRN THIRD TO HALF OF THE STATE AFTER 21Z WED...WHILE ISOLATED TO SCATTERED SHRA/TSRA LINGER ACROSS THE SOUTH. LOW TEMPS TONIGHT UNDER A FAIR AMOUNT OF CLOUD COVER /50-70 PERCENT/ WILL BE IN THE MID 50S TO MID 60S...WITH HIGH TEMPS WEDNESDAY VARYING FROM THE LOWER 70S ACROSS THE NRN MTNS...TO THE LOWER 80S IN THE SE. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... LG SCALE FORCING AND COOLER AIR ALOFT/STEEP MID-LVL LAPSE RATES TIED TO PASSAGE OF UPPER LEVEL TROUGH AXIS MAY PROVIDE ENOUGH LIFT TO GENERATE ISOLD...INSTABILITY TYPE SHOWERS ON THU AFTN. OTHERWISE ANTICIPATE A DRY PERIOD THROUGH THE UPCOMING WEEKEND AND INTO EARLY NEXT WEEK...WITH STRING OF PLEASANT DAYS/COMFORTABLE NIGHTS AS AREA REMAINS UNDER THE INFLUENCE OF SFC HIGH PRES MIGRATING S/SEWD FROM THE UPPER GRT LKS. TEMPS WILL START OUT BELOW AVG BEHIND THE DEPARTING TROUGH AXIS BUT SHOULD MODERATE AS HEIGHTS REBOUND BY 10/11 AUG. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... SURFACE HIGH PRESSURE WILL KEEP CLEAR SKIES AND VERY LIGHT WINDS ACROSS CENTRAL PA THROUGH THE OVERNIGHT HOURS. THOUGH NOT AS MUCH LOW LEVEL MOISTURE AROUND AS LAST NIGHT SO FOG WILL BE MORE LIMITED. ISOLATED IFR CONDITIONS POSS ACROSS NORTHERN AND CENTRAL MTNS...THOUGH MOST LOCATIONS SHOULD SETTLE INTO MVFR CONDITIONS DURING THE PREDAWN HOURS. CONDITIONS WILL QUICKLY RETURN TO VFR AREAWIDE DURING THE DAY TUESDAY. CLOUDS WILL REMAIN FEW TO SCATTERED IN THE SE HALF OF CWA...BUT A WEAK FRONTAL SYSTEM SLIDING INTO THE NW WILL BRING LOCAL MVFR CONDITIONS IN SCT AFTERNOON SHOWERS/ISO TSTMS. WINDS WILL REMAIN LIGHT. SCT MVFR RESTRICTIONS POSS AGAIN TONIGHT ALONG WITH LINGERING CHANCE FOR SHOWERS /MAINLY NORTHWEST/. SCT SHOWERS/TSTMS RETURN FOR WED. OUTLOOK... TUE...SCATTERED SHRA/TSRA WITH APPROACHING COLD FRONT...MAINLY NW. WED...SCATTERED SHRA/TSRA. THU-SAT...MAINLY VFR. PATCHY FOG POSSIBLE EARLY. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT LONG TERM...LAMBERT/STEINBUGL AVIATION...RXR
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
100 PM CDT TUE AUG 5 2014 .AVIATION 18Z DISCUSSION... SFC RIDGE EXTENDS FROM MIDDLE TN NE THROUGH PA. DEWPOINTS ARE STILL RATHER LOW WITH VALUES HOLDING IN THE 50S. THIS IS MINIMIZING OUR INSTABILITY LEVELS DESPITE THE WARM TEMPS. A FEW EXTRA CLOUDS...HOWEVER...ARE MOVING ACROSS THE AREA THIS AFTERNOON AND THAT SHOULD BE THE EXTENT OF OUR MOISTURE THROUGH THE TAF PD. SOME LIGHT FOG WILL BE POSSIBLE ACROSS THE TAF AREAS AROUND 12Z. OTW...TRANQUIL WEATHER IS EXPECTED ALTHOUGH HUMIDITY LEVELS WILL BE A LITTLE HIGHER TOMORROW. && .PREV DISCUSSION... /ISSUED 941 AM CDT TUE AUG 5 2014/ UPDATE... AREA OF STORMS EXTENDS FROM SOUTHERN IL SW TOWARD THE BOOTHEEL. THIS ACTIVITY IS WEAKENING AND IS NOT EXPECTED TO REACH THE MID STATE. HRRR FURTHER CONCURS WITH THIS SOLUTION SO OTHER THAN SOME INCREASED PARTIAL CLOUDINESS FOR TODAY...CONDITIONS SHOULD REMAIN DRY. OTW...SFC RIDGE STRETCHES FROM THE MID STATE NE TO PA. INSTABILITY CHARTS REVEAL THAT NOT MUCH OF ANY CAPE RETURN IS EXPECTED UNTIL TOMORROW AND THURSDAY. THEREFORE...WITH THE DRY STABLE CONDITIONS IN PLACE...NO POPS WILL BE ADDED TO TODAY`S FCST AT THIS TIME. TEMPS STILL EXPECTED TO REACH THE LOWER 90S FOR MANY AREAS. CURRENT TEMPS ARE IN THE MID TO UPPER 70S AND THIS IS IN LINE WITH THE LATEST NUMERICAL GUIDANCE. SO...ONLY CHANGE TO THE FCST WILL BE A LITTLE ADDED CLOUD COVER TO THE GRIDS. UPDATES WILL BE SENT OUT SHORTLY. PREV DISCUSSION... /ISSUED 601 AM CDT TUE AUG 5 2014/ UPDATE...ADDED AVIATION SECTION FOR 12Z TAF`S. AVIATION...BNA/CKV/CSV...SURFACE HIGH PRESSURE IS CURRENTLY CENTERED JUST EAST OF NASHVILLE, WITH A DRY AIR MASS IN PLACE OVER TENNESSEE AND GENERALLY LIGHT WINDS EXPECTED THE NEXT 24 HRS. WITH THE EXCEPTION OF MORNING RADIATION FOG AT CSV THROUGH 13Z, LOOK FOR VFR WX ACROSS MIDDLE TENNESSEE THROUGH THE TAF PERIOD. PREV DISCUSSION... /ISSUED 339 AM CDT TUE AUG 5 2014/ SHORT TERM...A RIDGE OF SURFACE HIGH PRESSURE, EXTENDING FROM THE VIRGINIAS ACROSS TENNESSEE AND INTO OKLAHOMA, WAS KEEPING SKIES CLEAR OVER THE MID STATE EARLY THIS MORNING. AT 2AM, TEMPERATURES WERE MAINLY IN THE LOWER AND MIDDLE 60S. ATMOSPHERE OVER THE MID STATE SHOULD REMAIN DRY ENOUGH TODAY TO KEEP US LOCKED INTO OUR CURRENT RAIN-FREE PATTERN. WITH MAXIMUM PERCENT SUNSHINE EXPECTED, BELIEVE WE WILL SEE TEMPERATURES SURGE TO THE SAME LEVELS AS YESTERDAY. CSV MAY EVEN BREAK THEIR 3-DAY STREAK OF MAXING OUT AT 83 DEGREES, AND NUDGE ON UP TO 84. YARDS AND GARDENS OVER MANY AREAS ARE NEEDING RAIN PRETTY BADLY AND, FORTUNATELY, WE HAVE REASON TO BE HOPEFUL FOR A GRADUAL CHANGE IN THE WEATHER PATTERN AS WE HEAD INTO THE MIDDLE AND LATTER PART OF THE WEEK. IF WE LOOK TO THE NORTHWEST THIS MORNING, UP OVER EAST- CENTRAL MISSOURI, WE SEE NOCTURNAL TSTMS IN PROGRESS, AND A HINT OF THE CHANGES THAT WILL BE COMING OUR WAY. LOOK FOR EASTERN MISSOURI TO BE A GOOD BREEDING GROUND FOR THUNDERSTORMS OVER THE NEXT 3 TO 5 DAYS, WITH THUNDERSTORMS EVENTUALLY PROPAGATING INTO OUR NECK OF THE WOODS. AS INTERMITTENT SHORTWAVES DROP SOUTHEASTWARD IN NORTHWEST FLOW, AND KICK OFF THUNDERSTORMS AND OUTFLOW BOUNDARIES, AND AS A LOW LEVEL COL CONVERGENCE BOUNDARY DEVELOPS OUT OF MISSOURI INTO WESTERN MIDDLE TN, WE WILL SEE SHOWERS AND STORMS BECOMING INCREASINGLY LIKELY HERE INT EH MID-STATE. UNFORTUNATELY, THE STORMS OVER EASTERN MISSOURI THIS MORNING WON`T DO US ANY GOOD, SINCE THEY SHOULD CONTINUE DROPPING MORE SOUTHWARD THAT EASTWARD. HOWEVER, THAT WILL CHANGE LATER TODAY AND TOMORROW. BY THIS AFTERNOON, EXPECT BEST CAPE TO BE OVER EASTERN MISSOURI AND SOUTHERN ILLINOIS, WITH TSTMS DEVELOPING IN THE AFTERNOON HEAT AND THEN SPILLING SOUTHEASTWARD TOWARD SOUTHWESTERN KY AND NORTHWESTERN MIDDLE TENNESSEE. AT LEAST A FEW ISOLATED RW/TRW COULD WORK THEIR WAY INTO NORTHWEST AND EXTREME N-CENTRAL PARTS OF OUR CWA LATE TONIGHT, ENHANCED BY A WEAK SFC CONVERGENCE BOUNDARY THAT IS FORECAST TO BE IN OUR NORTHWEST BY 12Z WED. AS WEAK SFC CONVERGENCE BOUNDARY MOVES EASTWARD AND DISSIPATES DURING THE DAY ON WEDNESDAY, CAPES WILL BE SUFFICIENT OVER SOUTHERN KENTUCKY AND MOST OF MIDDLE TENNESSEE TO ALLOW FOR ISOLATED TO SCATTERED CONVECTION (ESPECIALLY OVER NORTHERN AND EASTERN AREAS). MEANWHILE, EXPECT A SHORTWAVE TO FIRE MORE THUNDERSTORMS TO OUR NORTHWEST, BACK OVER SOUTHEASTERN MISSOURI. SOME OF THOSE STORMS ARE EXPECTED TO AFFECT OUR NORTHWESTERN COUNTIES WEDNESDAY NIGHT. HOWEVER, THE STORMS WILL BE WEAKENING AS THEY MOVE INTO OUR CWA AND MAY NOT PENETRATE OUR SOUTHERN AND EASTERN COUNTIES BEFORE DYING OUT. BY THURSDAY, CAPES OVER OUR AREA INCREASE TO 2500+ J/KG, AND ANOTHER SHORTWAVE SHOULD BE KICKING OFF THUNDERSTORMS OVER SOUTHEASTERN MISSOURI BY LATE MORNING. THESE STORMS WILL DROP SOUTHEASTWARD AND KICK OFF OUTFLOW BOUNDARIES WHICH WILL INTERACT WITH OUR HIGH CAPE ENVIRONMENT AND RESULT IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER MIDDLE TENNESSEE. OUR HIGH TEMPS ON THU WILL BE LARGELY DETERMINED BY HOW FAST THUNDERSTORMS DEVELOP OVERHEAD. WITH BOTH NAM AND GFS GIVING RELATIVELY CONSISTENT TEMPS FOR THUR, AM HESITANT TO SHAVE TOO MUCH OFF GUIDANCE NUMBERS. THUS, WILL PROBABLY ONLY LOWER FORECAST HIGH TEMPS BY 1 OR 2 DEGS. MOS POPS AREN`T MUCH HELP WITH THIS TYPE OF NORTHWEST FLOW PATTERN, AND TEND TO UNDERESTIMATE RAIN CHANCE. THEREFORE, WILL GO QUITE A BIT ABOVE MOS POP NUMBERS OVER THE NEXT SEVERAL DAYS. RATHER THAN GO WITH THE 20-30% MOS POPS FOR THU, WILL GO MORE LIKE 30-50%. LONG TERM...AS WE HEAD INTO THE WEEKEND AND EARLY NEXT WEEK, BELIEVE GFS IS NOT PROPERLY ACCOUNTING FOR THE EFFECTS OF CLOUDS AND SHOWERS. IT SEEMS TO KEEP MAX TEMPS TOO WARM. ON THE OTHER HAND, DON`T REALLY BUY THE SIGNIFICANTLY COOLER SOLUTION OF THE ECMWF. THEREFORE, WILL GO WITH A GENERALLY PERSISTENT PATTERN, WITH HIGHS TOPPING OUT NEAR CLIMO NORMS. REGARDING POPS IN THE EXTENDED, BELIEVE THE MEX NUMBERS MAY BE A BIT HIGH AND WILL TREND MORE TOWARD CLIMO BY THE LATTER PERIODS. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
941 AM CDT TUE AUG 5 2014 .UPDATE... AREA OF STORMS EXTENDS FROM SOUTHERN IL SW TOWARD THE BOOTHEEL. THIS ACTIVITY IS WEAKENING AND IS NOT EXPECTED TO REACH THE MID STATE. HRRR FURTHER CONCURS WITH THIS SOLUTION SO OTHER THAN SOME INCREASED PARTIAL CLOUDINESS FOR TODAY...CONDITIONS SHOULD REMAIN DRY. OTW...SFC RIDGE STRETCHES FROM THE MID STATE NE TO PA. INSTABILITY CHARTS REVEAL THAT NOT MUCH OF ANY CAPE RETURN IS EXPECTED UNTIL TOMORROW AND THURSDAY. THEREFORE...WITH THE DRY STABLE CONDITIONS IN PLACE...NO POPS WILL BE ADDED TO TODAY`S FCST AT THIS TIME. TEMPS STILL EXPECTED TO REACH THE LOWER 90S FOR MANY AREAS. CURRENT TEMPS ARE IN THE MID TO UPPER 70S AND THIS IS IN LINE WITH THE LATEST NUMERICAL GUIDANCE. SO...ONLY CHANGE TO THE FCST WILL BE A LITTLE ADDED CLOUD COVER TO THE GRIDS. UPDATES WILL BE SENT OUT SHORTLY. && .PREV DISCUSSION... /ISSUED 601 AM CDT TUE AUG 5 2014/ UPDATE...ADDED AVIATION SECTION FOR 12Z TAF`S. AVIATION...BNA/CKV/CSV...SURFACE HIGH PRESSURE IS CURRENTLY CENTERED JUST EAST OF NASHVILLE, WITH A DRY AIR MASS IN PLACE OVER TENNESSEE AND GENERALLY LIGHT WINDS EXPECTED THE NEXT 24 HRS. WITH THE EXCEPTION OF MORNING RADIATION FOG AT CSV THROUGH 13Z, LOOK FOR VFR WX ACROSS MIDDLE TENNESSEE THROUGH THE TAF PERIOD. PREV DISCUSSION... /ISSUED 339 AM CDT TUE AUG 5 2014/ SHORT TERM...A RIDGE OF SURFACE HIGH PRESSURE, EXTENDING FROM THE VIRGINIAS ACROSS TENNESSEE AND INTO OKLAHOMA, WAS KEEPING SKIES CLEAR OVER THE MID STATE EARLY THIS MORNING. AT 2AM, TEMPERATURES WERE MAINLY IN THE LOWER AND MIDDLE 60S. ATMOSPHERE OVER THE MID STATE SHOULD REMAIN DRY ENOUGH TODAY TO KEEP US LOCKED INTO OUR CURRENT RAIN-FREE PATTERN. WITH MAXIMUM PERCENT SUNSHINE EXPECTED, BELIEVE WE WILL SEE TEMPERATURES SURGE TO THE SAME LEVELS AS YESTERDAY. CSV MAY EVEN BREAK THEIR 3-DAY STREAK OF MAXING OUT AT 83 DEGREES, AND NUDGE ON UP TO 84. YARDS AND GARDENS OVER MANY AREAS ARE NEEDING RAIN PRETTY BADLY AND, FORTUNATELY, WE HAVE REASON TO BE HOPEFUL FOR A GRADUAL CHANGE IN THE WEATHER PATTERN AS WE HEAD INTO THE MIDDLE AND LATTER PART OF THE WEEK. IF WE LOOK TO THE NORTHWEST THIS MORNING, UP OVER EAST- CENTRAL MISSOURI, WE SEE NOCTURNAL TSTMS IN PROGRESS, AND A HINT OF THE CHANGES THAT WILL BE COMING OUR WAY. LOOK FOR EASTERN MISSOURI TO BE A GOOD BREEDING GROUND FOR THUNDERSTORMS OVER THE NEXT 3 TO 5 DAYS, WITH THUNDERSTORMS EVENTUALLY PROPAGATING INTO OUR NECK OF THE WOODS. AS INTERMITTENT SHORTWAVES DROP SOUTHEASTWARD IN NORTHWEST FLOW, AND KICK OFF THUNDERSTORMS AND OUTFLOW BOUNDARIES, AND AS A LOW LEVEL COL CONVERGENCE BOUNDARY DEVELOPS OUT OF MISSOURI INTO WESTERN MIDDLE TN, WE WILL SEE SHOWERS AND STORMS BECOMING INCREASINGLY LIKELY HERE INT EH MID-STATE. UNFORTUNATELY, THE STORMS OVER EASTERN MISSOURI THIS MORNING WON`T DO US ANY GOOD, SINCE THEY SHOULD CONTINUE DROPPING MORE SOUTHWARD THAT EASTWARD. HOWEVER, THAT WILL CHANGE LATER TODAY AND TOMORROW. BY THIS AFTERNOON, EXPECT BEST CAPE TO BE OVER EASTERN MISSOURI AND SOUTHERN ILLINOIS, WITH TSTMS DEVELOPING IN THE AFTERNOON HEAT AND THEN SPILLING SOUTHEASTWARD TOWARD SOUTHWESTERN KY AND NORTHWESTERN MIDDLE TENNESSEE. AT LEAST A FEW ISOLATED RW/TRW COULD WORK THEIR WAY INTO NORTHWEST AND EXTREME N-CENTRAL PARTS OF OUR CWA LATE TONIGHT, ENHANCED BY A WEAK SFC CONVERGENCE BOUNDARY THAT IS FORECAST TO BE IN OUR NORTHWEST BY 12Z WED. AS WEAK SFC CONVERGENCE BOUNDARY MOVES EASTWARD AND DISSIPATES DURING THE DAY ON WEDNESDAY, CAPES WILL BE SUFFICIENT OVER SOUTHERN KENTUCKY AND MOST OF MIDDLE TENNESSEE TO ALLOW FOR ISOLATED TO SCATTERED CONVECTION (ESPECIALLY OVER NORTHERN AND EASTERN AREAS). MEANWHILE, EXPECT A SHORTWAVE TO FIRE MORE THUNDERSTORMS TO OUR NORTHWEST, BACK OVER SOUTHEASTERN MISSOURI. SOME OF THOSE STORMS ARE EXPECTED TO AFFECT OUR NORTHWESTERN COUNTIES WEDNESDAY NIGHT. HOWEVER, THE STORMS WILL BE WEAKENING AS THEY MOVE INTO OUR CWA AND MAY NOT PENETRATE OUR SOUTHERN AND EASTERN COUNTIES BEFORE DYING OUT. BY THURSDAY, CAPES OVER OUR AREA INCREASE TO 2500+ J/KG, AND ANOTHER SHORTWAVE SHOULD BE KICKING OFF THUNDERSTORMS OVER SOUTHEASTERN MISSOURI BY LATE MORNING. THESE STORMS WILL DROP SOUTHEASTWARD AND KICK OFF OUTFLOW BOUNDARIES WHICH WILL INTERACT WITH OUR HIGH CAPE ENVIRONMENT AND RESULT IN THE DEVELOPMENT OF SCATTERED THUNDERSTORMS OVER MIDDLE TENNESSEE. OUR HIGH TEMPS ON THU WILL BE LARGELY DETERMINED BY HOW FAST THUNDERSTORMS DEVELOP OVERHEAD. WITH BOTH NAM AND GFS GIVING RELATIVELY CONSISTENT TEMPS FOR THUR, AM HESITANT TO SHAVE TOO MUCH OFF GUIDANCE NUMBERS. THUS, WILL PROBABLY ONLY LOWER FORECAST HIGH TEMPS BY 1 OR 2 DEGS. MOS POPS AREN`T MUCH HELP WITH THIS TYPE OF NORTHWEST FLOW PATTERN, AND TEND TO UNDERESTIMATE RAIN CHANCE. THEREFORE, WILL GO QUITE A BIT ABOVE MOS POP NUMBERS OVER THE NEXT SEVERAL DAYS. RATHER THAN GO WITH THE 20-30% MOS POPS FOR THU, WILL GO MORE LIKE 30-50%. LONG TERM...AS WE HEAD INTO THE WEEKEND AND EARLY NEXT WEEK, BELIEVE GFS IS NOT PROPERLY ACCOUNTING FOR THE EFFECTS OF CLOUDS AND SHOWERS. IT SEEMS TO KEEP MAX TEMPS TOO WARM. ON THE OTHER HAND, DON`T REALLY BUY THE SIGNIFICANTLY COOLER SOLUTION OF THE ECMWF. THEREFORE, WILL GO WITH A GENERALLY PERSISTENT PATTERN, WITH HIGHS TOPPING OUT NEAR CLIMO NORMS. REGARDING POPS IN THE EXTENDED, BELIEVE THE MEX NUMBERS MAY BE A BIT HIGH AND WILL TREND MORE TOWARD CLIMO BY THE LATTER PERIODS. && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1143 PM CDT MON AUG 4 2014 .DISCUSSION... SEE 06Z AVIATION DISCUSSION. && .AVIATION... ISOLATED SHRA CONTINUE NEAR THE COAST AND HAVE ADDED A VCSH FOR KLBX THROUGH 09Z. PATCHY FOG HAS ALSO BEGUN TO DEVELOP AND THINK THE BEST POTENTIAL FOR FOG WILL BE AT KLBX...KIAH AND KCXO. MODELS HAVE HAD SOME DIFFICULTY THE LAST COUPLE OF NIGHT WITH CIGS SO NOT TERRIBLY CONFIDENT WITH VFR CIGS ALL NIGHT. THE LATEST RAP AND 4 KM WRF FOCUS SOME AFTN SHRA OVER MAINLY THE NE HALF OF SE TX. FCST SOUNDINGS ALSO SHOW PW VALUES INCREASING TO AROUND 1.8-1.9 INCHES AROUND 21Z SO ADDED VCSH FOR KUTS AND KCXO FOR TUES AFTN. 43 && .PREV DISCUSSION... /ISSUED 904 PM CDT MON AUG 4 2014/ UPDATE... SEE DISCUSSION FOR EVENING UPDATE. DISCUSSION... NOT MANY CHANGES TO FORECAST PACKAGE THIS EVENING. PERSISTENT LOW PRESSURE OFF THE COAST OF LOUISIANA HAS FINALLY STARTED TO WASH OUT THIS EVENING. STILL GETTING SOME SHOWERS AND THUNDERSTORMS ACROSS OUR FAR NORTHERN ZONES AT THIS TIME BUT COVERAGE SHOULD CONTINUE TO QUICKLY DECREASE THANKS TO THE LOSS OF DAY TIME HEATING. TOMORROW AFTERNOON EXPECT SLIGHTLY WARMER HIGH TEMPERATURES AGAIN AS 850 TEMPERATURES CONTINUE THEIR SLOW CLIMB. MADE MINOR TWEAKS TO HIGH TEMPERATURE AND POP GRIDS BASED ON CURRENT TRENDS. NO OTHER CHANGES REQUIRED AT THIS TIME. 23 PREV DISCUSSION... /ISSUED 308 PM CDT MON AUG 4 2014/ DISCUSSION... FINALLY GETTING THE SCT PCPN THAT HAS BEEN ADVERTISED THESE LAST FEW DAYS (VIA THE PESKY LOW THAT MOVED IN FROM THE E YESTERDAY). PER SATELLITE/SFC ANALYSES THIS SYSTEM HAS WEAKENED CONSIDERABLY TODAY AND THIS TREND WILL LIKELY CONTINUE TONIGHT. OVERALL NOT A LOT OF CHANGE WITH THE FCST THE REST OF THE WEEK AS WE SETTLE IN- TO A MORE TYPICAL SUMMERTIME PATTERN OF WEAK UPPER LEVEL RIDGING (AS THE TROF MOVES OFF TO THE EAST). MOST NOTABLE CHANGES IN THE FCST APPEARS TO BE IN THE EXTENDED WHERE ECMWF HAS A MUCH STRONG- ER UPPER RIDGE SETTLING OVER THE STATE AT THE END OF THE WEEK AS OPPOSED TO THE GFS...WHICH IS NOW GOING WITH THE SHEAR AXIS/WEAK TROFFING SCENARIO. AS SUCH...WILL BE KEEPING WITH THE GOING FCST OF MAINLY DAYTIME SEABREEZE DRIVEN PCPN IN THE MID/EXTENDED PART OF THE FCST. ALSO NOT REALLY SOLD ON THE MOS GUIDANCE HIGH TEMPS FOR THE LATTER PART OF THE WEEK (GIVEN THE UNCERTAINTY REGARDING UPPER RIDGE STRENGTH) SO WILL KEEP THESE NUMBERS CLOSE TO NORMAL. 41 MARINE... EASTERLY WINDS ACROSS THE COASTAL WATERS THIS AFTERNOON WILL BECOME ONSHORE OVER THE NEXT 24 HOURS. THIS ONSHORE FLOW WILL PERSIST THROUGH THE END OF THE WEEK WITH WIND SPEEDS INCREASING LATE WEEK AS A SURFACE LOW BEGINS TO DEVELOP ACROSS THE SOUTHERN PLAINS. 38 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 74 94 75 95 75 / 30 20 20 20 10 HOUSTON (IAH) 75 93 76 95 76 / 30 20 20 20 10 GALVESTON (GLS) 79 91 81 91 81 / 30 20 20 20 20 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...23 AVIATION/MARINE...43
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AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
918 PM EDT WED AUG 6 2014 .SYNOPSIS... A COLD FRONT WILL SLIDE SOUTHEAST ACROSS THE REGION OVERNIGHT...REACHING THE CAROLINAS ON THURSDAY. HIGH PRESSURE SHOULD BUILD NORTH OF THE AREA THURSDAY INTO THURSDAY NIGHT BEFORE SLIDING OFF THE MID ATLANTIC COAST FRIDAY. A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE ALONG THE BOUNDARY TO THE SOUTH FRIDAY NIGHT THROUGH THE WEEKEND. && .NEAR TERM /THROUGH THURSDAY/... AS OF 845 PM EDT WEDNESDAY... WIDELY SCATTERED CONVECTION CONTINUES TO REDEVELOP ALONG RESIDUAL OUTFLOW THIS EVENING GIVEN LEFTOVER WEAK INSTABILITY PER SPC MESO ANALYSIS AND STEEP LAPSES ABOVE THE SURFACE OFF EVENING SOUNDINGS. HOWEVER CAP ALOFT AND DEEP WEST/NW FLOW HELPING TO KEEP THE LID ON WIDESPREAD DEEP CONVECTION SO STILL EXPECTING MOST SHRA TO FADE WITH LOSS OF HEATING. THIS IN LINE WITH THE LATEST SHORT TERM HRRR AND RAP WHICH SHOWS LITTLE COVERAGE SHORTLY AFTER SUNSET SO KEEPING POPS SIMILAR OVERNIGHT WITH FEW REMAINING SHRA BEFORE MIDNIGHT. OTRW WEAK FRONT NOW STILL NW OF THE MOUNTAINS TO DRIFT THROUGH LATE BEFORE DIPPING SOUTH OF THE AREA BY MORNING. CANT TOTALLY RULE OUT ISOLATED SHRA WITH THE BOUNDARY BUT GIVEN LACK OF SUPPORT THINK MAINLY PC OVERALL. LOW FOG STABILITY VALUES SUPPORT AT LEAST PATCHY FOG VALLEYS AND WHERE HEAVIER DOWNPOURS HAVE OCCURRED THIS EVENING SO BEEFING UP COVERAGE IN SPOTS. BUMPED UP LOWS A BIT GIVEN LINGERING MOIST DEWPOINTS/CLOUDS AND LAGGING COOL ADVECTION WELL TO THE NW BUT OVERALL MOSTLY 60S FOR LOWS. PREVIOUS VALID DISCUSSION... A COLD FRONT WAS MAKING ITS WAY INTO THE WESTERN PART OF THE FORECAST AREA. THE FRONT IS EXPECTED TO CROSS THE AREA TONIGHT AND BE SOUTH OF THE REGION BY THURSDAY MORNING. ISOLATED TO SCATTERED SHOWERS AND STORMS ARE EXPECTED THE REMAINDER OF THIS AFTERNOON INTO THE EVENING HOURS ALONG IN ADVANCE OF THE FRONT. HRRR AND RNK WRK- ARW MODELS HAVE BEEN DOING DO A GOOD JOB THE PAST FEW DAYS WITH TIMING AND LOCATION OF LATE AFTERNOON AND EARLY EVENING ACTIVITY. WILL CONTINUE PLACE STRONG WEIGHT ON THEIR SOLUTIONS FOR WHERE THE FOCUS OF THE BEST COVERAGE WILL BE. THAT REGION WILL PRIMARILY BE AREAS NEAR AND NORTHWEST TO NORTHEAST OF LYNCHBURG AND ALSO ACROSS THE NORTHERN MOUNTAINS OF NC AND PARTS OF THE MOUNTAIN EMPIRE AND NEW RIVER VALLEY REGION OF SOUTHWEST VIRGINIA. PRECIPITATION IS EXPECTED TO COMPLETELY DISSIPATE BETWEEN MIDNIGHT AND 200 AM TONIGHT. THE NOTABLY DRIER AIR BEHIND THE FRONT IS NOT EXPECT TO ARRIVE UNTIL THURSDAY AFTERNOON. THIS WILL ALLOW FOR ONE MORE NIGHT OF SOME PATCHY MOUNTAIN AND RIVER VALLEY FOG...ESPECIALLY IN AREAS THAT RECEIVE PRECIPITATION THIS AFTERNOON AND EVENING. HIGH LEVEL CLOUDS ARE EXPECTED OVERNIGHT FOR MUCH OF THE REGION. LOWER...MORE NUMEROUS CLOUDS ARE POSSIBLE NEAR A BLUEFIELD TO LEWISBURG WV LINE WHERE AN UPSLOPE FLOW WITHIN A SHALLOW MOIST LAYER WILL HELP RE- ESTABLISH LOW LEVEL CLOUDS AT AND BELOW THE INVERSION LEVEL. ON THURSDAY...HIGH PRESSURE WILL BUILD INTO OH/PA WITH THE SOUTHERN EXTENT OF ITS AXIS NOSING INTO THE FORECAST AREA. WITH IT WILL COME DRIER AND COOLER WEATHER. WHILE NOT FORECAST...WE MAY HAVE TO WATCH FOR SOME LATE DAY ISOLATED SHOWERS IN THE FAR SOUTHERN PART OF THE AREA WHERE DAYTIME HEATING WILL BE MAXIMIZED COINCIDENT TO WHERE THE BEST REMAINING LOW LEVEL MOISTURE WILL BE LOCATED. AT THIS TIME...CONFIDENCE IS TOO LOW TO INCLUDE THE ISOLATED SHOWERS IN THE FORECAST. HIGH TEMPERATURES WILL RANGE FROM AROUND 80 TO THE LOWER 80S ACROSS THE MOUNTAINS WITH LOW TO MID 80S ACROSS THE PIEDMONT. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... AS OF 400 PM EDT WEDNESDAY... THE FORECAST GOING INTO THE WEEKEND SHOULD LOOK FAMILIAR TO WHAT WAS EXPERIENCED THE END OF LAST WEEK WITH TRANSITION BACK TO MUCH COOLER THAN NORMAL TEMPERATURES. THE UPPER LEVEL PATTERN REMAINS PRETTY MUCH UNCHANGED...FAVORING A RIDGE OF HIGH PRESSURE OVER THE PLAINS AND ROCKIES...AND TROUGHINESS OVER THE EASTERN CONUS...THE DEGREE OF AMPLIFICATION THE ONLY THING THAT HAS BEEN CHANGING WITH TIME. TO START THE DAY FRIDAY...THE UPPER LEVEL TROUGH WILL SLIDE OFF THE EAST COAST WITH SURFACE HIGH PRESSURE WEDGING DOWN THE EAST SIDE OF THE APPALACHIANS. THIS WILL SET STAGE FOR A MULTIDAY PERIOD OF EASTERLY WINDS OFF THE ATLANTIC OCEAN...A PATTERN THAT GENERALLY FEATURES COOL TEMPERATURES AND ABUNDANT LOW LEVEL CLOUD COVER FOR MUCH OF OUR FORECAST AREA. TO GO ALONG WITH THE COOL CLOUD COVER THERE WILL BE SHOWERS. A SURFACE FRONT WILL BE NEARLY STATIONARY...JUST SOUTH OF OUR FORECAST AREA...EXTENDING FROM SOUTH CAROLINAS WESTWARD INTO THE MID MS VALLEY. THIS FRONT WILL BECOME THE FOCUS FOR SHOWERS AND THUNDERSTORMS...THE STRONGEST STORMS PRIMARILY SOUTH AND WEST OF OUR FORECAST AREA. WEDGE OF STABLE AIR ON THE EAST SIDE OF THE MTNS WILL PROHIBIT MUCH IN THE WAY OF STORMINESS HERE...HOWEVER COMBINATION OF ISENTROPIC LIFT...AND THE EASTERLY UPSLOPE WIND FLOW WILL PROVIDE LIFT FOR PERIODIC SHOWERS ACROSS OUR FCST AREA BEGINNING FRIDAY AND CONTINUING THROUGH THE WEEKEND. IN GENERAL...QPF IS EXPECTED TO BE LESS THAN AN INCH...WITH THE EXCEPTION OF AREAS WEST OF I77 WHERE MORE SUN AND INSTABILITY WILL EXIST...AND FARTHER SOUTH INTO NORTH CAROLINA CLOSER TO INFLUENCE OF THE SURFACE FRONT. BOTH THE GFS AND ECMWF DEVELOP CONVECTION ALONG AND NORTH OF THE FRONTAL BOUNDARY FROM THE LOWER MISSOURI VALLEY EAST TOWARD THE OHIO VALLEY LATE THURSDAY NIGHT...THEN RIDE THE CONVECTION SOUTHEAST INTO THE MOUNTAINS BY MIDDAY FRIDAY. RAIN SPREADS EAST FRIDAY AFTERNOON INTO FRIDAY NIGHT. THESE SAME MODELS ARE ALSO ADVERTISING HIGH CHC THREAT FOR PRECIP RIGHT ON THROUGH THE WEEKEND. WITH ABUNDANT CLOUD COVER...PRECIPITATION...AND AN EASTERLY WIND... WENT WELL BELOW CLIMO. HIGHS THIS WEEKEND WILL LIKELY BE 8 TO 15 DEGREES BELOW NORMAL. FOR SATURDAY WE WILL BE LUCKY TO TOUCH 70. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 410 PM EDT WEDNESDAY... COOL PATTERN LOOKS LIKE IT WILL LINGER THROUGH MONDAY BEFORE WARMING BACK UP THE MIDDLE OF NEXT WEEK. OVERALL THIS PERIOD WILL BE CHARACTERIZED BY THE SAME NEARLY STATIONARY...WAVY FRONT POSITIONED JUST SOUTH OF THE FORECAST AREA. SFC HIGH WILL BE OVER THE MID ATLANTIC/NORTHEAST WEDGING SW...BUT THIS AIRMASS IS EXPECTED TO MODIFY WITH TIME...RESULTING IN A UPWARD TEMPERATURE TREND TUESDAY AND WEDNESDAY. MAINTAINED DAILY THREAT FOR SHOWERS THROUGH THE PERIOD. INTRODUCED THUNDER BACK IN THE FORECAST FOR MID WEEK...THE RETURN OF SOME SUN PROVIDING INSTABILITY TO FEED DEEPER CONVECTION. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... AS OF 718 PM EDT WEDNESDAY... A WEAK AERA OF LOW PRESSURE WAS LOCATED IN WESTERN WEST VIRGINIA ALONG A COLD FRONT STRETCHING FROM EASTERN KENTUCKY INTO WEST VIRGINIA AND INTO NORTHEAST VIRGINIA. WIDELY SCATTERED SHOWERS...WITH A FEW RUMBLES OF THUNDER WILL GRADUALLY WANE THIS EVENING. SIMILAR TO LAST NIGHT...THIS ACTIVITY WILL LIKELY LINGER PAST SUNDOWN A FEW HOURS. AS A RESULT...INCLUDED A VCSH AT KBLF AND KDAN EARLY THIS EVENING. DRIER AIR WILL START ENTERING THE REGION LATER TONIGHT IN THE WAKE OF THE FRONT AND WITH THE ARRIVAL OF SURFACE HIGH PRESSURE. MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE NIGHT SAVE MOUNTAIN AND RIVER VALLEY PATCHY FOG. ENOUGH RESIDUAL LOW LEVEL MOISTURE MAY GET TRAPPED UNDER THE INVERSION AND LIFTED UPSLOPE IN THE WEST FOR A BRIEF PERIOD OF MVFR CIGS BETWEEN KBLF-KLWB. ANY SUB-VFR CONDITIONS WILL QUICKLY IMPROVE TO VFR AROUND 12-13Z/8-9AM THURSDAY. VFR CLOUDS WILL INCREASE ON THURSDAY...BUT DRY WEATHER IS EXPECTED. EXTENDED AVIATION DISCUSSION... LENGTHY PERIOD OF SUB-VFR CONDITIONS POSSIBLE FRIDAY INTO SATURDAY AS THE FRONT BUCKLES NORTH AGAIN WITH THE APPROACH AND PASSAGE OF AN AREA OF LOW PRESSURE. GOOD POTENTIAL FOR PLENTY OF RAIN...LOW CLOUDS AND REDUCED VISIBILITIES. SUNDAY INTO MONDAY...COLD AIR DAMMING WEDGE IN PLACE ACROSS THE EAST WITH POTENTIAL FOR CONTINUATION OF SUB-VFR CATEGORY CONDITIONS. MODELS VARY ON THE EXTENT ANOTHER UPPER LOW WILL SPREAD ADDITIONAL PRECIPITATION INTO AT LEAST THE WESTERN PARTS OF THE AREA BY MONDAY...POSSIBLY CONVECTIVE OUTSIDE THE INFLUENCE OF THE WEDGE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH NEAR TERM...DS/JH SHORT TERM...PM LONG TERM...PM AVIATION...DS/PH
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
719 PM EDT WED AUG 6 2014 .SYNOPSIS... A COLD FRONT WAS APPROAHCING OUR REGION FROM EASTERN KENTUCKY. THIS FRONT WILL MOVE SOUTH THROUGH THE REGION TONIGHT...REACHING THE GULF STATES BY LATE THURSDAY. A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE ALONG THE BOUNDARY FRIDAY THROUGH MONDAY. && .NEAR TERM /THROUGH THURSDAY/... AS OF 315 PM EDT WEDNESDAY... A COLD FRONT WAS MAKING ITS WAY INTO THE WESTERN PART OF THE FORECAST AREA. THE FRONT IS EXPECTED TO CROSS THE AREA TONIGHT AND BE SOUTH OF THE REGION BY THURSDAY MORNING. ISOLATED TO SCATTERED SHOWERS AND STORMS ARE EXPECTED THE REMAINDER OF THIS AFTERNOON INTO THE EVENING HOURS ALONG IN ADVANCE OF THE FRONT. HRRR AND RNK WRK- ARW MODELS HAVE BEEN DOING DO A GOOD JOB THE PAST FEW DAYS WITH TIMING AND LOCATION OF LATE AFTERNOON AND EARLY EVENING ACTIVITY. WILL CONTINUE PLACE STRONG WEIGHT ON THEIR SOLUTIONS FOR WHERE THE FOCUS OF THE BEST COVERAGE WILL BE. THAT REGION WILL PRIMARILY BE AREAS NEAR AND NORTHWEST TO NORTHEAST OF LYNCHBURG AND ALSO ACROSS THE NORTHERN MOUNTAINS OF NC AND PARTS OF THE MOUNTAIN EMPIRE AND NEW RIVER VALLEY REGION OF SOUTHWEST VIRGINIA. PRECIPITATION IS EXPECTED TO COMPLETELY DISSIPATE BETWEEN MIDNIGHT AND 200 AM TONIGHT. THE NOTABLY DRIER AIR BEHIND THE FRONT IS NOT EXPECT TO ARRIVE UNTIL THURSDAY AFTERNOON. THIS WILL ALLOW FOR ONE MORE NIGHT OF SOME PATCHY MOUNTAIN AND RIVER VALLEY FOG...ESPECIALLY IN AREAS THAT RECEIVE PRECIPITATION THIS AFTERNOON AND EVENING. HIGH LEVEL CLOUDS ARE EXPECTED OVERNIGHT FOR MUCH OF THE REGION. LOWER...MORE NUMEROUS CLOUDS ARE POSSIBLE NEAR A BLUEFIELD TO LEWISBURG WV LINE WHERE AN UPSLOPE FLOW WITHIN A SHALLOW MOIST LAYER WILL HELP RE- ESTABLISH LOW LEVEL CLOUDS AT AND BELOW THE INVERSION LEVEL. ON THURSDAY...HIGH PRESSURE WILL BUILD INTO OH/PA WITH THE SOUTHERN EXTENT OF ITS AXIS NOSING INTO THE FORECAST AREA. WITH IT WILL COME DRIER AND COOLER WEATHER. WHILE NOT FORECAST...WE MAY HAVE TO WATCH FOR SOME LATE DAY ISOLATED SHOWERS IN THE FAR SOUTHERN PART OF THE AREA WHERE DAYTIME HEATING WILL BE MAXIMIZED COINCIDENT TO WHERE THE BEST REMAINING LOW LEVEL MOISTURE WILL BE LOCATED. AT THIS TIME...CONFIDENCE IS TOO LOW TO INCLUDE THE ISOLATED SHOWERS IN THE FORECAST. HIGH TEMPERATURES WILL RANGE FROM AROUND 80 TO THE LOWER 80S ACROSS THE MOUNTAINS WITH LOW TO MID 80S ACROSS THE PIEDMONT. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/... AS OF 400 PM EDT WEDNESDAY... THE FORECAST GOING INTO THE WEEKEND SHOULD LOOK FAMILIAR TO WHAT WAS EXPERIENCED THE END OF LAST WEEK WITH TRANSITION BACK TO MUCH COOLER THAN NORMAL TEMPERATURES. THE UPPER LEVEL PATTERN REMAINS PRETTY MUCH UNCHANGED...FAVORING A RIDGE OF HIGH PRESSURE OVER THE PLAINS AND ROCKIES...AND TROUGHINESS OVER THE EASTERN CONUS...THE DEGREE OF AMPLIFICATION THE ONLY THING THAT HAS BEEN CHANGING WITH TIME. TO START THE DAY FRIDAY...THE UPPER LEVEL TROUGH WILL SLIDE OFF THE EAST COAST WITH SURFACE HIGH PRESSURE WEDGING DOWN THE EAST SIDE OF THE APPALACHIANS. THIS WILL SET STAGE FOR A MULTIDAY PERIOD OF EASTERLY WINDS OFF THE ATLANTIC OCEAN...A PATTERN THAT GENERALLY FEATURES COOL TEMPERATURES AND ABUNDANT LOW LEVEL CLOUD COVER FOR MUCH OF OUR FORECAST AREA. TO GO ALONG WITH THE COOL CLOUD COVER THERE WILL BE SHOWERS. A SURFACE FRONT WILL BE NEARLY STATIONARY...JUST SOUTH OF OUR FORECAST AREA...EXTENDING FROM SOUTH CAROLINAS WESTWARD INTO THE MID MS VALLEY. THIS FRONT WILL BECOME THE FOCUS FOR SHOWERS AND THUNDERSTORMS...THE STRONGEST STORMS PRIMARILY SOUTH AND WEST OF OUR FORECAST AREA. WEDGE OF STABLE AIR ON THE EAST SIDE OF THE MTNS WILL PROHIBIT MUCH IN THE WAY OF STORMINESS HERE...HOWEVER COMBINATION OF ISENTROPIC LIFT...AND THE EASTERLY UPSLOPE WIND FLOW WILL PROVIDE LIFT FOR PERIODIC SHOWERS ACROSS OUR FCST AREA BEGINNING FRIDAY AND CONTINUING THROUGH THE WEEKEND. IN GENERAL...QPF IS EXPECTED TO BE LESS THAN AN INCH...WITH THE EXCEPTION OF AREAS WEST OF I77 WHERE MORE SUN AND INSTABILITY WILL EXIST...AND FARTHER SOUTH INTO NORTH CAROLINA CLOSER TO INFLUENCE OF THE SURFACE FRONT. BOTH THE GFS AND ECMWF DEVELOP CONVECTION ALONG AND NORTH OF THE FRONTAL BOUNDARY FROM THE LOWER MISSOURI VALLEY EAST TOWARD THE OHIO VALLEY LATE THURSDAY NIGHT...THEN RIDE THE CONVECTION SOUTHEAST INTO THE MOUNTAINS BY MIDDAY FRIDAY. RAIN SPREADS EAST FRIDAY AFTERNOON INTO FRIDAY NIGHT. THESE SAME MODELS ARE ALSO ADVERTISING HIGH CHC THREAT FOR PRECIP RIGHT ON THROUGH THE WEEKEND. WITH ABUNDANT CLOUD COVER...PRECIPITATION...AND AN EASTERLY WIND... WENT WELL BELOW CLIMO. HIGHS THIS WEEKEND WILL LIKELY BE 8 TO 15 DEGREES BELOW NORMAL. FOR SATURDAY WE WILL BE LUCKY TO TOUCH 70. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 410 PM EDT WEDNESDAY... COOL PATTERN LOOKS LIKE IT WILL LINGER THROUGH MONDAY BEFORE WARMING BACK UP THE MIDDLE OF NEXT WEEK. OVERALL THIS PERIOD WILL BE CHARACTERIZED BY THE SAME NEARLY STATIONARY...WAVY FRONT POSITIONED JUST SOUTH OF THE FORECAST AREA. SFC HIGH WILL BE OVER THE MID ATLANTIC/NORTHEAST WEDGING SW...BUT THIS AIRMASS IS EXPECTED TO MODIFY WITH TIME...RESULTING IN A UPWARD TEMPERATURE TREND TUESDAY AND WEDNESDAY. MAINTAINED DAILY THREAT FOR SHOWERS THROUGH THE PERIOD. INTRODUCED THUNDER BACK IN THE FORECAST FOR MID WEEK...THE RETURN OF SOME SUN PROVIDING INSTABILITY TO FEED DEEPER CONVECTION. && .AVIATION /23Z WEDNESDAY THROUGH MONDAY/... AS OF 718 PM EDT WEDNESDAY... A WEAK AERA OF LOW PRESSURE WAS LOCATED IN WESTERN WEST VIRGINIA ALONG A COLD FRONT STRETCHING FROM EASTERN KENTUCKY INTO WEST VIRGINIA AND INTO NORTHEAST VIRGINIA. WIDELY SCATTERED SHOWERS...WITH A FEW RUMBLES OF THUNDER WILL GRADUALLY WANE THIS EVENING. SIMILAR TO LAST NIGHT...THIS ACTIVITY WILL LIKELY LINGER PAST SUNDOWN A FEW HOURS. AS A RESULT...INCLUDED A VCSH AT KBLF AND KDAN EARLY THIS EVENING. DRIER AIR WILL START ENTERING THE REGION LATER TONIGHT IN THE WAKE OF THE FRONT AND WITH THE ARRIVAL OF SURFACE HIGH PRESSURE. MAINLY VFR CONDITIONS ARE EXPECTED THROUGH THE NIGHT SAVE MOUNTAIN AND RIVER VALLEY PATCHY FOG. ENOUGH RESIDUAL LOW LEVEL MOISTURE MAY GET TRAPPED UNDER THE INVERSION AND LIFTED UPSLOPE IN THE WEST FOR A BRIEF PERIOD OF MVFR CIGS BETWEEN KBLF-KLWB. ANY SUB-VFR CONDITIONS WILL QUICKLY IMPROVE TO VFR AROUND 12-13Z/8-9AM THURSDAY. VFR CLOUDS WILL INCREASE ON THURSDAY...BUT DRY WEATHER IS EXPECTED. EXTENDED AVIATION DISCUSSION... LENGTHY PERIOD OF SUB-VFR CONDITIONS POSSIBLE FRIDAY INTO SATURDAY AS THE FRONT BUCKLES NORTH AGAIN WITH THE APPROACH AND PASSAGE OF AN AREA OF LOW PRESSURE. GOOD POTENTIAL FOR PLENTY OF RAIN...LOW CLOUDS AND REDUCED VISIBILITIES. SUNDAY INTO MONDAY...COLD AIR DAMMING WEDGE IN PLACE ACROSS THE EAST WITH POTENTIAL FOR CONTINUATION OF SUB-VFR CATEGORY CONDITIONS. MODELS VARY ON THE EXTENT ANOTHER UPPER LOW WILL SPREAD ADDITIONAL PRECIPITATION INTO AT LEAST THE WESTERN PARTS OF THE AREA BY MONDAY...POSSIBLY CONVECTIVE OUTSIDE THE INFLUENCE OF THE WEDGE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS NEAR TERM...DS SHORT TERM...PM LONG TERM...PM AVIATION...DS/PH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CDT WED AUG 6 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 245 PM CDT WED AUG 6 2014 NON-DISCREET FLOW WILL KEEP THINGS RELATIVELY QUIET WELL INTO THE LONG TERM SO MAIN FOCUS IS ANY RAIN CHANCES ALONG MAINLY WESTERN AND SOUTHERN TIERS THROUGH REMAINDER OF WEEK. AREA REMAINS SOMEWHAT SANDWICHED BETWEEN STRONGER NORTHWEST FLOW TO THE EAST...WEAK SHORT WAVE TROUGHS ACROSS CENTRAL PLAINS AND EMBEDDED IN WESTERLIES ACROSS SOUTHERN CANADA. WITH SLOW EVOLVEMENT IN ANY PATTERN CHANGES...HIGH PRESSURE OVER ONTARIO AND WESTERN GREAT LAKES WILL KEEP FRONTAL BOUNDARY...WHERE PRECIPITATION IS FOCUSED...SOUTH OF AREA. DRIER AIR KEEPING RAIN JUST SOUTHWEST OF AREA WITH COOLER TEMPERATURES WHERE CLOUDS ARE THICKEST AND SEASONAL CONDITIONS FURTHER NORTH/EAST. NOT MUCH CHANGE IS EXPECTED TONIGHT AND THURSDAY. SUBTLE DIFFERENCES IN SHORT TERM MODELS BUT SHORT WAVE ENERGY WILL KEEP THINGS MOST ACTIVE ALONG FRONTAL BOUNDARY. GIVEN PERSISTENCE...HAVE LOWERED OVERALL RAIN THREAT ALONG SOUTHWEST SERVICE AREA BORDER IN ALIGNMENT WITH SURROUNDING FORECAST OFFICES AND CONTINUED CUT BACK IN TEMPERATURES WHERE CLOUD COVER WILL BE MOST IN PLACE. GIVEN WEAK FLOW AND MOISTURE REBOUND EXPECTED THIS EVENING...COULD SEE MORE PATCHY FOG TONIGHT...BETWEEN THICKER CLOUD COVER AND DRIER AIR TO THE NORTHEAST. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 245 PM CDT WED AUG 6 2014 SIMILAR SETUP THURSDAY NIGHT AND FRIDAY WITH RAIN THREAT PRIMARILY TO THE SOUTHWEST/SOUTH OF SERVICE AREA. LARGER QUESTIONS ABOUND WITH MEDIUM RANGE GUIDANCE OCCASIONALLY TRYING TO DEVELOP A WEAK CLOSED UPPER LOW AS WAVE EJECTS OUT OF WESTERN STATES TOWARDS THE WEEKEND. ECMWF HAS BEEN THE STEADY MODEL KEEPING A BROAD RIDGE WITH HIGH PRESSURE LOCKED OVER GREAT LAKES UNTIL POSSIBLY LATE SUNDAY WHEN WESTERLIES ACROSS CANADA TRY TO SWEEP A COLD FRONT IN. EVEN AS THAT HAPPENS EARLY NEXT WEEK...LOTS OF UNCERTAINTIES ON HOW ACTIVE FRONT WILL BE WITH SUCH WEAK CONVERGENCE ALONG IT. BOTTOM LINE IS RAIN THREATS REMAIN LOW THROUGH TUESDAY OF NEXT WEEK AND MANY AREAS COULD REMAIN COMPLETELY DRY THROUGH THAT POINT. GUIDANCE IN FAIR AGREEMENT THAT FLOW BECOMES MORE ACTIVE BY MID PART OF NEXT WEEK THOUGH WITH ZONAL OR SLIGHTLY SOUTHWEST FLOW COULD LEAD TO WARM AIR/MOISTURE RETURN AND STORMS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1100 PM CDT WED AUG 6 2014 FORECAST CONCERNS CONTINUE TO FOCUS ON A FOG THREAT...SPECIFICALLY IN THE RIVER VALLEYS...WITH A GREATER IMPACT AT KLSE AS A RESULT. SHOWERS AND STORMS PERSIST ACROSS SOUTHERN IA AND MO LATE THIS EVENING...SENDING SOME HIGH CIRRUS THIS WAY. IT APPEARS TO BE THIN IN NATURE THOUGH...AND ITS IMPACT ON DIURNAL COOLING COULD BE NEGLIGIBLE. SFC WINDS ARE GENERALLY LIGHT EAST TO CALM...WITH BUFKIT SOUNDINGS POINTING TO THIS LIGHT WIND LAYER EXTENDING UPWARDS OF 4K FT. PREVIOUS RAP AND NAM INCREASE WINDS JUST OFF THE SFC BEFORE 12Z...AND THIS SUGGESTION IS STILL THERE IN LATEST MODEL RUNS...BUT MORESO TOWARD 12Z RATHER THAN EARLIER. WITH AN INVERSION ALREADY IN PLACE...THIS LATE INCREASE IN WIND SHOULD HAVE MINIMAL IMPACT AT THE SFC. KLSE T/TD SPREAD WAS 7 DEGREES AT 03Z...RIGHT ON THE EDGE OF WHAT LOCAL STUDIES FAVOR FOR 1/4SM FORMATION. HOWEVER...COUPLE THIS WITH THE LIGHT WIND PROFILE AND CONDITIONS ARE LOOKING MORE FAVORABLE FOR FOG IN THE RIVER VALLEYS...AND AT LEAST SUB 1SM AT KLSE. ANY FOG THAT DEVELOPS SHOULD LIFT BY 14Z. FOR KRST...SIMILAR T/TD SPREAD AND LIGHT WIND FIELD. EXPECT SOME MVFR VSBYS FOR A PERIOD OVERNIGHT INTO THE EARLY MORNING HOURS. CONDITIONS AT BOTH SITES SHOULD THEN BE VFR INTO THURSDAY NIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...SHEA LONG TERM....SHEA AVIATION.....RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
956 AM CDT TUE AUG 5 2014 .UPDATE... NEARLY OVERCAST CONDITIONS REMAIN ACROSS THE SOUTHWEST HALF OF THE FORECAST AREA THIS MORNING. LATEST SATELLITE TRENDS AND MODEL SOUNDINGS INDICATE THAT THIS CLOUD DECK SHOULD BREAK UP A BIT LATE MORNING INTO THE AFTERNOON...ALLOWING FOR SOME SUNSHINE. THIS SHOULD RESULT IN TEMPS WARMING TO FORECAST HIGHS. A COUPLE MODELS ARE SHOWING A FEW SHOWERS OR SPRINKLES MAINLY IN THE WEST THIS AFTERNOON. THERE WILL BE SOME INSTABILITY...BUT NOT SEEING MUCH A TRIGGER...SO WILL KEEP THE FORECAST DRY FOR NOW. && .AVIATION/18Z TAFS/... CONDITIONS HAVE RETURNED TO MAINLY VFR ACROSS THE NORTHEAST FORECAST AREA THIS MORNING. LOW CIGS REMAIN ACROSS THE SOUTHWEST...BUT IMPROVEMENT IS EXPECTED LATE MORNING INTO THE AFTERNOON AS THIS CLOUD DECK ERODES FROM THE NORTHEAST. ADDITIONALLY...DAYTIME MIXING SHOULD HELP TO BREAK UP THE CLOUDS SOME AND RAISE THE CLOUD BASES. COULD SEE SOME PATCHY FOG TONIGHT...BUT OTHERWISE EXPECT VFR CONDITIONS TONIGHT INTO WEDNESDAY AS HIGH PRESSURE SITS OVER THE GREAT LAKES. && .PREV DISCUSSION... /ISSUED 312 AM CDT TUE AUG 5 2014/ SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. THE MID/UPPER LEVEL TROUGH WILL EXIT THE LAKE MICHIGAN AREA AROUND SUNRISE THIS MORNING. THE 250 MB JET MAX BEHIND THE TROUGH INCREASES TO 100 KNOTS THIS AFTERNOON OVER WISCONSIN BEFORE MOVING INTO LOWER MICHIGAN EARLY WEDNESDAY MORNING. THIS PUTS SOUTHWEST WISCONSIN IN THE LEFT EXIT REGION OF THE JET. AS A RESULT UPPER DIVERGENCE INCREASES OVER MUCH OF SOUTH CENTRAL AND FAR SOUTHEAST WISCONSIN. THE MODERATE 700 MB UPWARD MOTION IS FARTHER SOUTH ACROSS IOWA AND NORTHWEST ILLINOIS LATE TONIGHT. AS A RESULT MOST MODELS KEEP THE PRECIPITATION JUST SOUTHWEST AND SOUTH OF THE FORECAST AREA. HOWEVER THE NAM DOES BRING SOME PRECIPITATION TO AREAS MAINLY SOUTHWEST OF MADISON. WILL INCLUDE A CHANCE OF SHOWERS LATE TONIGHT TO ACCOUNT FOR THIS POSSIBILITY. 850 MB MOISTURE REMAINS TODAY BEFORE DRYING FROM THE NORTHEAST TONIGHT EXCEPT FOR THE FAR SOUTHWEST. ZERO TO 1 KM MIXED LAYER CAPE REACHES 1000 JOULES/KG ALONG THE ILLINOIS BORDER WITH LESS THAN 200 JOULES/KG NEAR SHEBOYGAN. THEREFORE ISOLATED SHOWERS ARE NOT OUT OF THE QUESTION. HOWEVER THE HRRR IS DRY THROUGH 19Z WITH ONLY A FEW SHOWERS POSSIBLE ALONG THE LAKE BREEZE FRONT. THE 00Z HIGH RES WRF/ARW DOES BRING A FEW ISOLATED LIGHT SHOWERS. OTHERWISE THE MAIN PROBLEM IS FOG...WITH A FEW AREAS DENSE...DURING THE EARLY MORNING TODAY. THE FOG/STRATUS WILL DISSIPATE IN THE MID/LATE MORNING HOURS. TUESDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE HIGH. A LARGE UPPER LOW WILL SIT OVER JAMES BAY THROUGH SATURDAY. THE TROUGH WILL EXTEND ALL THE WAY DOWN ACROSS THE SOUTHEAST STATES. NORTHWEST FLOW WILL PREVAIL ACROSS SOUTHERN WI. WEAK SHORTWAVES ROTATING AROUND THE UPPER LOW AND STEEP LOW LEVEL LAPSE RATES WILL LEAD TO SCATTERED DIURNAL SHOWERS WITH A FEW RUMBLES OF THUNDER EACH DAY FROM LATE MORNING THROUGH EARLY EVENING. AFTERNOON CAPE VALUES WILL BE ON THE LOWER SIDE...AROUND 100 TO 300 J/KG... ON WEDNESDAY...THUS LOWER CHANCES FOR THUNDER. HIGHER VALUES OF 700-900 J/KG CAPE ARE EXPECTED FOR THU AND FRIDAY AFTERNOONS. THE MORE DISTINCT AND AGREED UPON BETWEEN MODELS SHORTWAVE TROUGH SHOULD SWING THROUGH SOUTHERN WI FRIDAY AFTERNOON/EVENING...THUS THE BEST DAY FOR MORE WIDESPREAD AND HEAVIER SHOWERS AND THUNDERSTORMS. 850MB TEMPS WILL BE AROUND 10C TO 12C AND 925MB TEMPS AROUND 19C THROUGHOUT THE WEEK. THIS TRANSLATES TO HIGHS IN THE UPPER 70S TO AROUND 80 AND LOWS IN THE 50S. LONG TERM... SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM. THE UPPER TROUGH WILL BEGIN TO SHIFT EAST LATER SATURDAY THROUGH SUNDAY. SHOWERS ARE POSSIBLE ONCE AGAIN SATURDAY AFTERNOON...BUT LESS LIKELY ON SUNDAY AS DRY HIGH PRESSURE SLIDES ACROSS THE WESTERN GREAT LAKES. A SURFACE AND UPPER LOW PRESSURE TROUGH WILL LIKELY LINGER OVER NORTHERN WI SUNDAY NIGHT. MEANWHILE...SOUTHERLY FLOW ON THE BACK SIDE OF THE HIGH WILL ALLOW 850MB TEMPS TO INCREASE TO 14C AND 925MB TEMPS TO AROUND 22C BY MONDAY MORNING. EVENTUALLY...THAT SURFACE TROUGH WILL SLIDE DOWN THROUGH SOUTHERN WI TO BRING THE NEXT CHANCE FOR SHOWERS AND THUNDERSTORMS MONDAY AFTERNOON AND NIGHT. DRY AND COOL HIGH PRESSURE IS EXPECTED TO SET UP ONCE AGAIN EARLY NEXT WEEK. AVIATION/12Z TAFS/... SATURATED LOW LEVELS WILL BRING AREAS OF IFR/LIFR FOG/STRATUS. A FEW SPOTS WILL BE AROUND 1/4 MILE. THE FOG AND STRATUS WILL LIFT/DISSIPATE DURING THE MID/LATE MORNING. THEN MVFR CIGS BECOMING MAINLY VFR LATER THIS AFTERNOON. ISOLATED SHOWERS [POSSIBLE MAINLY THIS AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES TONIGHT. SHOWERS POSSIBLE LATE TONIGHT SOUTHWEST OF MADISON ASSOCIATED WITH AN UPPER JET MAX. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...DDV TODAY/TONIGHT AND AVIATION...HENTZ WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
312 AM CDT TUE AUG 5 2014 .SHORT TERM... TODAY AND TONIGHT...FORECAST CONFIDENCE IS HIGH. THE MID/UPPER LEVEL TROUGH WILL EXIT THE LAKE MICHIGAN AREA AROUND SUNRISE THIS MORNING. THE 250 MB JET MAX BEHIND THE TROUGH INCREASES TO 100 KNOTS THIS AFTERNOON OVER WISCONSIN BEFORE MOVING INTO LOWER MICHIGAN EARLY WEDNESDAY MORNING. THIS PUTS SOUTHWEST WISCONSIN IN THE LEFT EXIT REGION OF THE JET. AS A RESULT UPPER DIVERGENCE INCREASES OVER MUCH OF SOUTH CENTRAL AND FAR SOUTHEAST WISCONSIN. THE MODERATE 700 MB UPWARD MOTION IS FARTHER SOUTH ACROSS IOWA AND NORTHWEST ILLINOIS LATE TONIGHT. AS A RESULT MOST MODELS KEEP THE PRECIPITATION JUST SOUTHWEST AND SOUTH OF THE FORECAST AREA. HOWEVER THE NAM DOES BRING SOME PRECIPITATION TO AREAS MAINLY SOUTHWEST OF MADISON. WILL INCLUDE A CHANCE OF SHOWERS LATE TONIGHT TO ACCOUNT FOR THIS POSSIBILITY. 850 MB MOISTURE REMAINS TODAY BEFORE DRYING FROM THE NORTHEAST TONIGHT EXCEPT FOR THE FAR SOUTHWEST. ZERO TO 1 KM MIXED LAYER CAPE REACHES 1000 JOULES/KG ALONG THE ILLINOIS BORDER WITH LESS THAN 200 JOULES/KG NEAR SHEBOYGAN. THEREFORE ISOLATED SHOWERS ARE NOT OUT OF THE QUESTION. HOWEVER THE HRRR IS DRY THROUGH 19Z WITH ONLY A FEW SHOWERS POSSIBLE ALONG THE LAKE BREEZE FRONT. THE 00Z HIGH RES WRF/ARW DOES BRING A FEW ISOLATED LIGHT SHOWERS. OTHERWISE THE MAIN PROBLEM IS FOG...WITH A FEW AREAS DENSE...DURING THE EARLY MORNING TODAY. THE FOG/STRATUS WILL DISSIPATE IN THE MID/LATE MORNING HOURS. TUESDAY NIGHT THROUGH FRIDAY...FORECAST CONFIDENCE HIGH. A LARGE UPPER LOW WILL SIT OVER JAMES BAY THROUGH SATURDAY. THE TROUGH WILL EXTEND ALL THE WAY DOWN ACROSS THE SOUTHEAST STATES. NORTHWEST FLOW WILL PREVAIL ACROSS SOUTHERN WI. WEAK SHORTWAVES ROTATING AROUND THE UPPER LOW AND STEEP LOW LEVEL LAPSE RATES WILL LEAD TO SCATTERED DIURNAL SHOWERS WITH A FEW RUMBLES OF THUNDER EACH DAY FROM LATE MORNING THROUGH EARLY EVENING. AFTERNOON CAPE VALUES WILL BE ON THE LOWER SIDE...AROUND 100 TO 300 J/KG... ON WEDNESDAY...THUS LOWER CHANCES FOR THUNDER. HIGHER VALUES OF 700-900 J/KG CAPE ARE EXPECTED FOR THU AND FRIDAY AFTERNOONS. THE MORE DISTINCT AND AGREED UPON BETWEEN MODELS SHORTWAVE TROUGH SHOULD SWING THROUGH SOUTHERN WI FRIDAY AFTERNOON/EVENING...THUS THE BEST DAY FOR MORE WIDESPREAD AND HEAVIER SHOWERS AND THUNDERSTORMS. 850MB TEMPS WILL BE AROUND 10C TO 12C AND 925MB TEMPS AROUND 19C THROUGHOUT THE WEEK. THIS TRANSLATES TO HIGHS IN THE UPPER 70S TO AROUND 80 AND LOWS IN THE 50S. .LONG TERM... SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM. THE UPPER TROUGH WILL BEGIN TO SHIFT EAST LATER SATURDAY THROUGH SUNDAY. SHOWERS ARE POSSIBLE ONCE AGAIN SATURDAY AFTERNOON...BUT LESS LIKELY ON SUNDAY AS DRY HIGH PRESSURE SLIDES ACROSS THE WESTERN GREAT LAKES. A SURFACE AND UPPER LOW PRESSURE TROUGH WILL LIKELY LINGER OVER NORTHERN WI SUNDAY NIGHT. MEANWHILE...SOUTHERLY FLOW ON THE BACK SIDE OF THE HIGH WILL ALLOW 850MB TEMPS TO INCREASE TO 14C AND 925MB TEMPS TO AROUND 22C BY MONDAY MORNING. EVENTUALLY...THAT SURFACE TROUGH WILL SLIDE DOWN THROUGH SOUTHERN WI TO BRING THE NEXT CHANCE FOR SHOWERS AND THUNDERSTORMS MONDAY AFTERNOON AND NIGHT. DRY AND COOL HIGH PRESSURE IS EXPECTED TO SET UP ONCE AGAIN EARLY NEXT WEEK. && .AVIATION/12Z TAFS/... SATURATED LOW LEVELS WILL BRING AREAS OF IFR/LIFR FOG/STRATUS. A FEW SPOTS WILL BE AROUND 1/4 MILE. THE FOG AND STRATUS WILL LIFT/DISSIPATE DURING THE MID/LATE MORNING. THEN MVFR CIGS BECOMING MAINLY VFR LATER THIS AFTERNOON. ISOLATED SHOWERS [POSSIBLE MAINLY THIS AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE GREAT LAKES TONIGHT. SHOWERS POSSIBLE LATE TONIGHT SOUTHWEST OF MADISON ASSOCIATED WITH AN UPPER JET MAX. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...HENTZ WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
117 PM MDT TUE AUG 5 2014 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY NIGHT) ISSUED AT 230 PM MDT TUE AUG 5 2014 WATER VAPOR IMAGERY STILL SHOWING MONSOONAL MOISTURE OVER THE STATE OF WYOMING THIS AFTERNOON...BUT A LARGE DRY SLOT CONTINUES TO EDGE NORTHEAST FROM UTAH AND SOUTHWESTERN COLORADO. PLUME OF DEEPEST MOISTURE IS NOW OFF TO OUR EAST IN CENTRAL NEBRASKA AND SOUTH DAKOTA. AT THE SURFACE...THE FRONTAL BOUNDARY THAT MOVED INTO THE AREA LAST NIGHT AND THIS MORNING IS LAYING UP AGAINST THE LARAMIE RANGE AND IS THE FOCUS FOR SHOWERS AND THUNDERSTORM DEVELOPMENT. MOSAIC RADAR SHOWS CONVECTION CONCENTRATED EAST OF THE LARAMIE RANGE AND ACROSS THE SOUTHERN PANHANDLE SO FAR TODAY. WIDELY SCATTERED SHOWERS AND THUNDERSTORMS ACROSS SOUTHWESTERN WYOMING AND NORTHWESTERN COLORADO CONTINUE TO MOVE NORTHEAST. SOME OF THIS ACTIVITY WILL MAKE ITS WAY INTO CARBON AND ALBANY COUNTIES THIS AFTERNOON IF IT HOLDS TOGETHER. MINOR WAVE SEEN ON WATER VAPOR IMAGERY WILL TRACK FROM SOUTHWEST WYOMING THROUGH CENTRAL WYOMING AND THEN EAST IN SOUTH DAKOTA THROUGH THE AFTERNOON. THIS SHOULD AID IN INCREASING PRECIP COVERAGE. LATEST HRRR FORECAST SHOWS BANDS OF SHOWERS/TSTMS DEVELOPING OVER THE LARAMIE RANGE...THEN MOVING EAST NORTHEAST INTO THE PANHANDLE THIS AFTERNOON. COULD SEE A MARGINALLY SEVERE THUNDERSTORM EVENT ACROSS THE NORTHERN PANHANDLE TODAY WITH SBCAPES AROUND 1200-1400 J/KG AROUND ALLIANCE AND CHADRON. THEY ARE STILL CAPPED PRETTY GOOD THOUGH SO FAR. NAM SOUNDINGS SHOWING THIS CAP BREAKING AROUND 21Z OR SO AND HRRR SHOWING A PRETTY STRONG CELL DEVELOPING SOUTH OF MONTROSE IN SIOUX COUNTY OUT IN THE NORTHERN PANHANDLE BY LATE AFTERNOON. WITH THE SHORTWAVE MOVING THROUGH THE AREA THIS EVENING...THE FRONTAL SYSTEM BEGINS TO BE LIFTED NORTHEAST. SHOWERS AND THUNDERSTORMS SHOULD DECREASE IN COVERAGE ACROSS EXTREME SOUTHEAST WYOMING AND THE SOUTHERN PANHANDLE THIS EVENING. SHOWERS AND THUNDERSTORMS RETURN WEDNESDAY AFTERNOON WITH THE ECMWF AND NAM/WRF MODELS IN GOOD AGREEMENT. BEST AREA FOR CONVECTION LOOKS TO BE EAST OF THE LARAMIE RANGE AND THE PANHANDLE BY MID AFTERNOON PERSISTING INTO MID EVENING BEFORE TAPERING OFF WITH LOSS OF DAYTIME HEATING. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 1159 AM MDT TUE AUG 5 2014 THURSDAY...EVEN THOUGH RIDGING ALOFT WILL LIMIT AREAL THUNDERSTORM COVERAGE...LOOKS LIKE ENOUGH LOW AND MID LEVEL MOISTURE FOR LATE DAY ISOLATED TO SCATTERED THUNDERSTORMS...MOST NUMEROUS FROM SIDNEY TO CHADRON WHERE UPWARD VERTICAL MOTION WILL BE MOST PRONOUNCED. FRIDAY...INCREASE IN LOW AND MID LEVEL MOISTURE ALONG WITH A WELL PRONOUNCED LOW AND MID LEVEL THETA-E RIDGE AXIS WILL AID IN AT LEAST SCATTERED AFTERNOON THUNDERSTORMS EAST OF INTERSTATE 25. SATURDAY...AS THE ATMOSPHERE DRIES SOMEWHAT FROM FRIDAY...WE EXPECT A CORRESPONDING DECREASE INT THE AREAL THUNDERSTORM COVERAGE. BEST CHANCES FOR STORMS WILL BE ALONG WESTERN NEBRASKA WHERE A LOW LEVEL CONVERGENCE AXIS IS PROGGED TO DEVELOP. SUNDAY/TUESDAY...ISOLATED LATE DAY THUNDERSTORMS WILL OCCUR WITH ADEQUATE LOW AND MID LEVEL MOISTURE AND WEAK LOW LEVEL UPSLOPE EAST WINDS. MONDAY...MINIMAL THUNDERSTORM CHANCES WITH RIDGING ALOFT AND LIMITED LOW AND MID LEVEL MOISTURE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING) ISSUED AT 1047 AM MDT TUE AUG 5 2014 USED LATEST HRRR MODEL RUN TO DETERMINE PRECIP LOCATION AND TIMING FOR OUR SOUTHEAST WYOMING AND NEBRASKA PANHANDLE TAFS THIS AFTERNOON. THIS MODEL HAS BEEN DOING VERY WELL ON CONVECTIVE INITIATION AND TIMING. IFR STRATUS TO RETURN LATE TONIGHT FOR THE NORTHERN PANHANDLE AS WELL. && .FIRE WEATHER... ISSUED AT 230 PM MDT TUE AUG 5 2014 MONSOONAL MOISTURE FROM THE SOUTHWEST WILL CONTINUE TO BRING THE AREA CHANCES FOR SHOWERS AND THUNDERSTORMS THROUGH THE WEEK. AFTERNOON HUMIDITIES EXPECTED TO REMAIN ABOVE CRITICAL THRESHOLDS THROUGH SATURDAY...MAINLY FALLING TO THE LOW TO MID 20 PERCENT RANGE. EXPECT FAIR OVERNIGHT RECOVERIES IN HUMIDITY WEST OF THE LARAMIE RANGE WITH EXCELLENT RECOVERIES EAST. DECREASING COVERAGE OF SHOWERS AND THUNDERSTORMS FROM TODAY ON FOR THE MOST PART AS MONSOONAL MOISTURE GETS SHUNTED SOUTH AND EAST. WINDS TO REMAIN LIGHT THROUGH THE WEEK AS WELL...KEEPING ELEVATED FIRE WEATHER CONDITIONS IN CHECK. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...CLAYCOMB LONG TERM...RUBIN AVIATION...CLAYCOMB FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1054 AM MDT TUE AUG 5 2014 .UPDATE... ISSUED AT 1047 AM MDT TUE AUG 5 2014 WITH DENSE CLOUD CANOPY AND UPSLOPING CONDITIONS...TEMPERATURES HAVE BEEN SLOW TO WARM LATE THIS MORNING. WENT AHEAD AND LOWERED MAX TEMPERATURES 3-4 DEGREES FOR MOST AREAS EAST OF THE LARAMIE RANGE FOR THIS AFTERNOON. PROBABLY STILL TOO HIGH. WOULD NOT BE SURPRISED IF CHEYENNE DOES NOT GET OUT OF THE 60S TODAY. UPDATES HAVE BEEN SENT. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 345 AM MDT TUE AUG 5 2014 PREDAWN WATER VAPOR IMAGERY REVEALED A UPPER RIDGE CENTERED OVER THE HIGH PLAINS AND UPPER TROUGH FROM THE NORTHERN ROCKIES THROUGH CA. A SHORTWAVE TROUGH WAS LIFTING NORTHWARD ACROSS THE FOUR CORNERS ENHANCING TSTORM ACTIVITY OVER EASTERN UT/WESTERN CO. EXPANSIVE PLUME OF SUBTROPICAL/MONSOON MOISTURE WAS ADVECTED NORTHEAST FROM THE GREAT BASIN THROUGH THE CENTRAL/SOUTHERN ROCKIES AND HIGH PLAINS. THE REGIONAL SURFACE ANALYSIS DEPICTED A STATIONARY FRONT FROM EASTERN MT TO ALONG THE LARAMIE RANGE AND INTO NORTHERN KS. SHOWERS/ISOLATED TSTORMS OBSERVED EARLIER OVER EAST CENTRAL WY MOVED INTO NORTHEAST WY/WESTERN SD. SKIES WERE MOSTLY CLOUDY WITH TEMPERATURES IN THE MID 50S TO MID 60S. WINDS WERE VARIABLE 5-10 MPH. THE LATEST SHORT RANGE MODEL CONSENSUS CONTINUES THE UNSETTLED WEATHER PATTERN AS THE UPPER RIDGE AXIS REMAINS ANCHORED OVER OR JUST EAST OF THE FRONT RANGE WITH A UPPER TROUGH ACROSS THE INTERMOUNTAIN WEST. SHORTWAVE TO THE SOUTHWEST RIDES NORTHEAST ACROSS CO AND WY THIS AFTERNOON. ACTIVE SUBTROPICAL MOISTURE PLUME INTERACTING WITH THE WAVE AND INSTABILITY WILL ENHANCE SHOWER/TSTORM DEVELOPMENT WITH THE POTENTIAL FOR LOCALLY HEAVY RAIN. WHILE THE SEVERE THREAT REMAINS LOW... SMALL HAIL AND GUSTY WINDS WILL ACCOMPANY THE STRONGER TSTORMS. SHOWER COVERAGE DECREASES FROM SOUTH TO NORTH TONIGHT AS SOME DRIER AIR ALOFT EDGES INTO THE REGION FROM CO. ISOLATED SHOWERS/TSTORMS WILL CONTINUE NORTH OF A RAWLINS TO ALLIANCE LINE WEDNESDAY MORNING. ANOTHER SHORTWAVE BREAKS DOWN THE RIDGE AS IT MOVES EAST ACROSS WY WEDNESDAY AFTERNOON. MOISTURE PLUME WILL EXTEND FROM NORTHWEST TO SOUTHEAST WITH SCATTERED SHOWERS/TSTORMS DEVELOPING AREAWIDE. CONVECTION ENDS BY MIDNIGHT WEDNESDAY NIGHT WITH SOMEWHAT DRIER AIR ALOFT SPREADING NORTHEAST INTO THE CWA. ON THURSDAY...SOME MORNING SHOWERS WILL DEVELOP EAST OF A DOUGLAS TO SIDNEY LINE AS YET ANOTHER SHORTWAVE RIDES SOUTHEAST ON LEE SIDE OF THE UPPER RIDGE. A RESURGENCE OF MONSOON MOISTURE INTERACTING WITH ANOTHER PASSING WAVE WILL INCREASE SHOWER/TSTORM COVERAGE OVER THE PLAINS DURING THE AFTERNOON. TEMPERATURES DURING THE SHORT TERM WILL AVERAGE NEAR SEASONAL NORMALS WITH HIGHS IN THE 80S LOWER ELEVATIONS AND 60S/70S FOR THE HIGH COUNTRY. LOWS WILL RANGE FROM THE 50S TO LOWER 60S WITH 40S FOR THE MOUNTAINS AND HIGH VALLEYS. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 312 AM MDT TUE AUG 5 2014 CONFIDENCE IS LOW IN THE EXTENDED FCST PERIOD WITH A MUDDLED UPPER LEVEL PATTERN IN PLACE. MEDIUM RANGE MODEL GUIDANCE STILL STRUGGLES WITH THE TIMING AND PLACEMENT OF SIGNIFICANT SYSTEMS...WHICH COULD HAVE AN IMPACT ON PCPN CHANCES ACROSS THE CWA. GENERALLY THE CENTRAL ROCKIES WILL REMAIN ON THE NORTH SIDE OF BROAD/FLAT RIDGING FROM THE SOUTHERN PLAINS INTO THE FOUR CORNERS. PCPN CHANCES WILL BE GOVERNED BY INDIVIDUAL DISTURBANCES TRAVERSING THE FLOW. LITTLE CHANGE IN THE ECMWF WITH A SHORTWAVE MEANDERING SLOWLY ACROSS CENTRAL WY THROUGH EARLY SAT. THE GFS IS THE MORE PROGRESSIVE MODEL WHICH WOULD SUPPORT A QUICK SHOT OF SHOWERS AND TSTMS AS OPPOSED TO A MORE WIDESPREAD AND LONGER DURATION EVENT. 700-300 MILLIBAR RH PROGS FROM BOTH GFS AND ECMWF SHOW POCKETS OF MONSOONAL MOISTURE MOVING ACROSS THE CWA THROUGH MOST OF THE PERIOD. THIS IS ENOUGH TO SUPPORT ISOLATED POPS EVEN AT NIGHT AS ENOUGH FORCING SHOULD EXIST WITH MORE PRONOUNCED WAVES AND OCCASIONAL LOW LEVEL UPSLOPE ALONG THE LARAMIE RANGE. FRIDAY SHOULD FEATURE THE BEST CHANCE FOR PCPN WITH GOOD DYNAMIC FORCING OVER OUR EASTERN ZONES. DID NOT FEEL COMFORTABLE GOING HIGHER THAN 40 PERCENT POPS IN MOST CASES GIVEN THE VAST MODEL DIFFERENCES IN QPF. AS FAR AS TEMPERATURES ARE CONCERNED...SEASONAL. WARMING AND DRYING TREND MON AND TUE AS THE UPPER RIDGE BUILDS BACK INTO THE AREA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY MORNING) ISSUED AT 1047 AM MDT TUE AUG 5 2014 USED LATEST HRRR MODEL RUN TO DETERMINE PRECIP LOCATION AND TIMING FOR OUR SOUTHEAST WYOMING AND NEBRASKA PANHANDLE TAFS THIS AFTERNOON. THIS MODEL HAS BEEN DOING VERY WELL ON CONVECTIVE INITIATION AND TIMING. IFR STRATUS TO RETURN LATE TONIGHT FOR THE NORTHERN PANHANDLE AS WELL. && .FIRE WEATHER... ISSUED AT 253 AM MDT TUE AUG 5 2014 A PREVAILING SOUTHWEST FLOW ALOFT BETWEEN A RIDGE ACROSS THE HIGH PLAINS AND TROUGH OVER THE INTERMOUNTAIN WEST WILL CONTINUE TO ADVECT SUBTROPICAL MOISTURE ACROSS THE DISTRICTS THROUGH THE END OF THE WEEK. WEAK UPPER LEVEL DISTURBANCES AND A SURFACE BOUNDARY EAST OF THE FRONT RANGE WILL ENHANCE LIFT FOR SHOWERS AND THUNDERSTORMS...MOST NUMEROUS THIS AFTERNOON AND EARLY EVENING. WETTING RAINFALL AND HIGH RELATIVE HUMIDITY WILL PRECLUDE FIRE WEATHER CONCERNS. WINDS WILL AVERAGE AROUND 10 MPH...EXCEPT VARIABLE AND GUSTY IN AND NEAR THUNDERSTORMS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ UPDATE...CLAYCOMB SHORT TERM...JAMSKI LONG TERM...HAMMER AVIATION...CLAYCOMB FIRE WEATHER...JAMSKI
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1127 PM MDT MON AUG 4 2014 .SHORT TERM...(THIS EVENING THROUGH TUESDAY EVENING) ISSUED AT 230 PM MDT MON AUG 4 2014 CURRENTLY...WATER VAPOR IMAGERY SHOWING MONSOONAL MOISTURE MOVING INTO OUR WESTERN ZONES THIS AFTERNOON AS THE UPPER LOW THAT WAS OVER SOUTHERN CALIFORNIA YESTERDAY MOVES INTO CENTRAL UTAH. 12Z PWATS ON THE GJT SOUNDING OVER 1.2 INCHES. THIS MOISTURE IS HEADED OUR WAY. MOSAIC RADAR SHOWING FAIRLY WIDESPREAD LIGHT RAIN OVER CARBON COUNTY. A FEW THUNDERSTORMS DEVELOPING NEAR ARLINGTON AND CENTENNIAL WITH A FEW LIGHTNING STRIKES OBSERVED. BEGINNING TO SEE SOME CELLS DEVELOPING ON THE RADAR UP BY VEDAUWOO...SO SHOWERS HERE AT CHEYENNE ARE NOT THAT FAR OFF. FOR THIS AFTERNOON...LATEST HRRR FORECAST SHOWING CELLS DEVELOPING OVER THE LARAMIE RANGE AND DRIFTING EAST. ITS SHOWING A FAIRLY WIDESPREAD BAND OF SHOWERS AND THUNDERSTORMS MOVING SLOWLY EAST INTO THE PANHANDLE AROUND THE 23Z TIME FRAME. STORMS ARE GOING TO BE VERY SLOW MOVING...FROM THE SOUTHWEST AT UNDER 5KTS. THOSE AREAS THAT DO EXPERIENCE THUNDERSTORMS THIS AFTERNOON AND THIS EVENING COULD SEE CONSIDERABLE RAINFALL WITH THESE SLOW MOVING STORMS. UPPER SHORTWAVE MOVES BEST LIFT NORTH THIS EVENING...SO WE SHOULD SEE A LULL IN CONVECTION AFTER 03Z OR SO UNTIL TUESDAY. DRIED OUT THE SOUTHERN PANHANDLE AND SOUTHEAST WYOMING FROM LARAMIE TO WHEATLAND TO TORRINGTON THIS EVENING. NEXT PIECE OF ENERGY TO MOVE THROUGH THE AREA TUESDAY AFTERNOON AND EVENING AS THE UPPER LOW OPENS UP AND TRACKS INTO WESTERN WYOMING. NAM AND ECMWF SHOW GOOD QPF ACROSS MOST OF THE CWFA...CONCENTRATED ACROSS THE SOUTHERN PANHANDLE AND LARAMIE COUNTY TUESDAY AFTERNOON. STILL NOT MUCH IN THE STEERING FLOW...SO STORMS WILL ONCE AGAIN BE SLOW MOVING AND PRODUCING MODERATE TO HEAVY RAINFALL INTO TUESDAY EVENING. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 1222 PM MDT MON AUG 4 2014 WEDNESDAY...DESPITE A SHORTWAVE RIDGE ALOFT OVER OUR COUNTIES...WITH A LOW LEVEL CONVERGENCE BOUNDARY INDICATED FROM DOUGLAS TO CHEYENNE...ALONG WITH ADEQUATE LOW AND MID LEVEL MOISTURE AND DECENT UPWARD VERTICAL MOTION FROM DOUGLAS TO CHEYENNE...HAVE BOOSTED AFTERNOON AND EVENING POPS INTO THE 45 TO 70 PERCENT RANGE...WITH LESSER POPS ELSEWHERE. WITH WEAK STEERING WINDS...WILL LIKELY SEE A FEW HEAVY RAINERS AS WELL. THURSDAY...NEXT SHORTWAVE TROUGH ALOFT MOVES INTO WESTERN WYOMING AND UTAH...WHILE A LOW LEVEL CONVERGENCE AXIS SETS UP FROM NORTH CENTRAL COLORADO NORTHWARD TO NEAR TORRINGTON TO NEAR CHADRON. 850/700 MB THETA-E RIDGE AXIS...WELL PRONOUNCED...WILL EXTEND NORTH TO SOUTH IN THE AFTERNOON ACROSS FAR EASTERN WYOMING AND WESTERN NEBRASKA...AND WITH PROGGED INSTABILITIES...CAPE AND DECENT DIRECTIONAL SHEAR...EXPECT A FEW STRONG TO SEVERE THUNDERSTORMS EAST OF A LUSK TO CHEYENNE LINE...AND HAVE ALSO BOOSTED POPS EAST OF THIS LINE TO THE 50 TO 60 PERCENT RANGE WITH ALL CONVECTIVE AND MESOSCALE PARAMETERS COMING TOGETHER. FRIDAY...LESS LATE DAY COVERAGE OF SHOWERS AND THUNDERSTORMS EXPECTED WITH DECREASE IN LOW AND MID LEVEL MOISTURE...THOUGH WILL STILL SEE ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS IN THE AFTERNOON AND EVENING WITH MOIST UPSLOPE MECHANICAL LIFT. SATURDAY...SIMILAR SCENARIO TO FRIDAY...ALBEIT WITH SLIGHTLY LESS COVERAGE OF SHOWERS AND THUNDERSTORMS DUE TO LESS LOW AND MID LEVEL MOISTURE AVAILABILITY. SUNDAY...RIDGING ALOFT STRENGTHENS OVER OUR COUNTIES...THUS EXPECT SLIGHTLY LESS COVERAGE OF LATE DAY SHOWERS AND THUNDERSTORMS...FOCUSED ALMOST EXCLUSIVELY OVER THE MOUNTAINS AND HIGHER TERRAIN SUCH AS THE PINE RIDGE FROM NEAR LUSK TO NEAR CHADRON. MONDAY...EVEN MORE PRONOUNCED RIDGING ALOFT...AND WITH THE BULK OF THE MONSOONAL MOISTURE RESIDING OVER COLORADO...WILL ONLY FORECAST ISOLATED LATE DAY THUNDERSTORMS OVER AND NEAR THE SNOWY...SIERRA MADRE AND SOUTHERN LARAMIE RANGES...THOUGH WE WILL NEED TO WATCH FOR POSSIBLE GREATER INTRUSION OF MID LEVEL MONSOONAL MOISTURE AS IS TYPICAL FOR LATE JULY AND EARLY AUGUST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY EVENING) ISSUED AT 1122 PM MDT MON AUG 4 2014 SHOWERS WILL CONTINUE TO DECREASE IN COVERAGE THROUGH THE LATE EVENING HOURS. MVFR TO IFR CIGS AND VSBYS ARE EXPECTED TO DEVELOP OVER THE NORTHERN NE PANHANDLE AFTER 09Z TUE...MAINLY FOR KAIA AND KCDR. CONDITIONS WILL BE SLOW TO IMPROVE ACROSS THOSE AREAS ON TUE WITH AT LEAST MVFR CONDITIONS EXPECTED TO PERSIST THROUGH AT LEAST EARLY AFTN. VFR CONDITIONS EXPECTED ELSEWHERE...WITH MORE SHOWERS AND STORMS EXPECTED AFTER 17-18Z AND POTENTIAL FOR BRIEF MVFR VSBYS AND GUSTY WINDS/SMALL HAIL. && .FIRE WEATHER... ISSUED AT 230 PM MDT MON AUG 4 2014 MONSOONAL MOISTURE WILL STAY WITH US THROUGH MOST OF THE WEEK GIVING MOST AREAS CHANCES FOR WETTING RAINS AND THUNDERSTORMS ON A DAILY BASIS. WINDS TO REMAIN WEAK AND AFTERNOON HUMIDITIES FAIRLY HIGH...MITIGATING ANY FIRE WEATHER CONCERNS. MIN HUMIDITIES EXPECTED TO STAY IN THE MID 20 PERCENT RANGE THROUGH THE WEEK WITH EXCELLENT OVERNIGHT RECOVERIES. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...CLAYCOMB LONG TERM...RUBIN AVIATION...HAMMER FIRE WEATHER...CLAYCOMB
AREA FORECAST DISCUSSION
NWS TUCSON AZ
910 PM MST WED AUG 6 2014 .SYNOPSIS...DRIER AIR WILL LIMIT THUNDERSTORMS TO MAINLY NEAR THE NEW MEXICO BORDER THROUGH TOMORROW. COVERAGE OF THUNDERSTORMS WILL THEN GRADUALLY INCREASE FRIDAY THROUGH SUNDAY AS DEEPER MOISTURE RETURNS TO THE AREA. THEREAFTER...SCATTERED MAINLY AFTERNOON AND EVENING THUNDERSTORMS WILL PREVAIL INTO THE MIDDLE OF NEXT WEEK. && .DISCUSSION...04Z INFRARED SATELLITE IMAGERY SHOWED WARMING CLOUD TOPS OVER EXTREME SERN COCHISE COUNTY WHERE WE SAW SOME WEAK TO MODERATE SHWR ACTIVITY EARLIER THIS EVE...A RESULT OF CONVECTION WHICH SPILLED NORTH OVER THE INTERNATIONAL BORDER. A FEW VERY WEAK ECHOES REMAINED IN EXTREME SRN COCHISE CNTY WHICH ARE EXPECTED TO DISSIPATE FAIRLY QUICKLY. ELSEWHERE ACROSS SERN AZ...SKIES WERE CLEAR TO MOSTLY CLEAR WITH A FEW LINGERING MAINLY CIRRUS LEVEL CLOUDS. AREA SFC TEMPS RANGED FROM THE LOW 90S TO THE UPPER 70S WITH THE HIGHEST DEWPOINTS...NOT SURPRISINGLY...ACROSS COCHISE CNTY. LATEST HRRR AND LOCAL WRF MODELS INDICATING AT THIS TIME THAT ANY PRECIP SHOULD BE DONE FOR THE NIGHT...ALTHOUGH SOME UPSCALE GROWTH IS STILL OCCURRING OVER CNTRL SONORA WITH CLOUD TOPS COOLING AND APPROACHING 50 KFT. CANNOT RULE OUT THE POSSIBILITY OF AN OUTFLOW FROM THIS COMPLEX PUSHING NORTH INTO SANTA CRUZ AND/OR COCHISE COUNTIES LATER TONIGHT HELPING TO ENHANCE SOME CLOUD COVER AND POSSIBLY A STRAY SHOWER OR TWO. THE OFFICIAL FORECAST HAS SLIGHT CHC POPS IN FOR THESE AREAS UNTIL 06Z AND THEN SINGLE DIGIT POPS FOR THE REST OF THE NIGHT. THIS LOOKS GOOD FOR NOW...SO NO UPDATES ARE PLANNED AT THIS TIME. FOR MORE DETAIL...PLEASE SEE THE PREVIOUS DISCUSSION BELOW. && .AVIATION...VALID THRU 07/23Z. ISOLATED -TSRA/-SHRA NEAR THE NEW MEXICO BORDER...ESPECIALLY ACROSS THE CHIRICAHUA MOUNTAINS NE OF KDUG THRU THE EARLY EVENING HOURS TONIGHT AND AGAIN AFT 07/21Z. CLOUDS THRU 07/06Z AND AFT 07/19Z... SKC-FEW CLOUDS AT 10-13K FT AGL WEST OF KTUS...WITH KTUS VICINITY EWD FEW-SCT CUMULUS CLOUDS AT 8-12K FT AGL...AND SCT-BKN CLOUDS ABOVE 20K FT AGL MAINLY SE OF KTUS. MOSTLY CLEAR SKIES EXPECTED BETWEEN 07/06Z AND 07/19Z. SURFACE WIND MAINLY LESS THAN 10 KTS... ALTHOUGH A FEW GUSTS TO AROUND 20 KTS MAY OCCUR THRU THE EARLY EVENING HOURS TONIGHT...AND AGAIN THURSDAY AFTERNOON. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...DRY CONDITIONS ARE EXPECTED THROUGH THURSDAY EXCEPT FOR ISOLATED AFTERNOON/EARLY EVENING THUNDERSTORMS MAINLY NEAR THE NEW MEXICO BORDER. ISOLATED TO SCATTERED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL RETURN ON FRIDAY...WITH THE COVERAGE OF THE THUNDERSTORMS INCREASING THIS WEEKEND. AFTERNOON WINDS WILL GENERALLY BE LESS THAN 15 MPH...EXPECT FOR STRONG AND GUSTY WINDS NEAR ANY THUNDERSTORMS. && .PREV DISCUSSION...HEADING INTO THIS WEEKEND...HIGH PRESSURE RIDGE AXIS WILL EXTEND FROM THE TX PANHANDLE SWWD THRU BAJA CALIFORNIA WITH THE GREAT BASIN TROF WEAKENING AND LIFTING OFF TO THE EAST. FOR A SHORT TIME...WEAK ZONAL FLOW WILL SET UP OVER THE MAJORITY OF THE CONUS. LATE IN THE WKEND ANOTHER TROF WILL DROP SWD ALONG THE PAC COASTLINE AS HIGH PRESSURE RETURNS TO A MORE FAVORABLE LOCATION FOR DEEPER MOISTURE ADVECTION AND SUBSEQUENT SHWR/TSTORM ACTIVITY ACROSS SE AZ. DIFFERENCES STILL EXIST BETWEEN EACH OF THE MODELS ON THE DAY THAT MORE WIDESPREAD SHOWERS/TSTMS WILL RETURN TO THE AREA. WITHOUT GOING INTO ALL THAT DETAIL...THE OFFICIAL FORECAST WILL SHOW A GRADUAL DAILY INCREASE IN SHWRS/TSTMS FRI-SUN. THUS...SCATTERED MAINLY AFTERNOON/EVENING SHWRS/TSTMS MAY RETURN AS EARLY AS SAT...THOUGH ALMOST CERTAINLY BY SUN. DEEPER SELY FLOW WILL RETURN EARLY NEXT WEEK...WHICH IS EXPECTED TO YIELD THE DAILY CYCLE OF SCATTERED MAINLY AFTERNOON/EVENING SHWRS/TSTMS. A VERY GRADUAL AND WEAK DAILY COOLING TREND WILL OCCUR THUR-SAT FOLLOWED BY NO SIGNIFICANT CHANGE IN DAYTIME TEMPS SUN-WED. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1130 PM MDT WED AUG 6 2014 .UPDATE... ISSUED AT 933 PM MDT WED AUG 6 2014 NO MAJOR CHANGES TO THE GOING FORECAST. REMOVED POPS FOR THE REST OF THE NIGHT...WITH THE EXCEPTION OF EXTREME NORTHERN EL PASO COUNTY. RADAR INDICATES A WEAK ROUGE CELL NEAR MONUMENT HILL TRACKING EAST...AND MAY CLIP THE COUNTY BOUNDARY THROUGH 11 PM. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 317 PM MDT WED AUG 6 2014 CURRENTLY... WEAK BOUNDARY WAS MOVING SOUTH ACROSS THE EASTERN PLAINS. THIS BOUNDARY WAS INITIATING SOME CONVECTION OVER KIOWA COUNTY AT 2 PM. GENERALLY N OF HIGHWAY 50 WINDS WERE FROM A WEAK NORTHERLY COMPONENT WHILE WINDS WERE GENERALLY LIGHT AND VARIABLE SOUTH OF 50. OVER THE MTNS...ESPECIALLY INTERIOR MTNS...IT HAS DRIED OUT QUITE A BIT WITH DWPTS IN THE 30S...WITH A FEW 20S AT HIGHER ELEVATIONS. IT ALSO APPEARS TO BE DRIER ALOFT AS CLOUDS ARE NOTICEABLY MUCH LESS ONCE YOU GET SOUTH OF US-50. REST OF TODAY INTO TONIGHT... MAIN CONCERN IN THE IMMEDIATE SHORT TERM WILL BE THE WALDO BURN SCAR. HRRR SHOWING BEST CHANCE OF PRECIP THIS AFTERNOON MAINLY OVER C MTNS...GREATER PIKES PEAK REGION AND KIOWA COUNTY. HAVE ALREADY INCREASED POPS THIS AREA IN EARLIER UPDATES. ALTHOUGH FLASH FLOODING NOT LIKELY OVER BURN SCARS...ONE HEAVY SHOWER IN THE WRONG PLACE CAN EASILY CAUSE PROBLEMS. FOR LATER TONIGHT...LOW LVL MOISTURE WILL LIKELY INCREASE...ESPECIALLY OVER THE FAR E PLAINS AS 60 DWPTS CURRENTLY IN SW NEB ARE SHUNTED SOUTHWARD BEHIND THE FRONT. WE WILL LIKELY SEE SOME LOW CLOUDS TOMORROW MORNING...ESPECIALLY OVER THE FAR SE PLAINS IN THE GREATER KIOWA COUNTY REGION. NAM GUIDANCE HAS SOME PRECIP LATE TONIGHT THIS REGION BUT IT IS LIKELY A BIT OVERDONE. WITH DRIER AIR OVER THE MTNS...WILL LIKELY SEE ANOTHER COOL NIGHT OVER THE HIGHER TRRN...ESPECIALLY ALONG THE CONTDVD AND HIGH VALLEYS. TOMORROW... EXPECT MORE CONVECTION OVER THE AREA TOMORROW AND HAVE POPS DRAWN UP EVERYWHERE OVER THE CWA BY TOMORROW AFTERNOON. PWAT VALUES INCREASE TO OVER AN INCH OVER THE PLAINS AND AREA WILL LIKELY BE FEELING THE LEADING EDGE OF A WELL DEFINED TROUGH OVER E UTAH. CONVECTION SHOULD INITIATE AROUND ITS NORMAL TIME OVER THE MTNS (NOONISH) AND THEN INCREASE AND MOVE EAST OVER THE PLAINS. BEST CHANCE OF POPS WILL BE OVER C MTNS...PIKES PEAK AREA AND FAR E PLAINS...ESPECIALLY BY LATE AFTERNOON. FLOODING THREAT ON THE BURN SCARS WILL BE HIGHER TOMORROW THAN TODAY. STORMS MAY BE A BIT MORE ORGANIZED TOMORROW DUE TO A BIT BETTER DEEP SHEAR AND HIGHER CAPE VALUES. AN ISOLD SVR STORM CANT BE RULED OUT. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 317 PM MDT WED AUG 6 2014 .THURSDAY EVENING AND FRIDAY...MAIN CHALLENGE WILL BE THE MOVEMENT OF THE MCS WHICH DEVELOPS OVER NORTHEAST COLORADO...AND THE AMOUNT OF MOISTURE AND INSTABILITY FROM THE OUTFLOW. OVER NORTHEAST COLORADO MOST MODELS DEVELOP CONVECTION THURSDAY AFTERNOON AND EVENING...WHICH MOVES TO THE EAST OR EAST SOUTHEAST DURING THE EVENING. BELIEVE MOST OF THE CONVECTION WILL STAY TO THE NORTH OF THE CWA...BUT THERE IS THREAT FOR SOME OF THE CONVECTION TO DEVELOP OVER THE PALMER DIVIDE REGION AND MOVE TO THE SOUTHEAST DURING THURSDAY EVENING. POPS GRIDS KEEP SCATTERED POPS OVER THESE REGIONS FOR THURSDAY EVENING AND INTO THE OVERNIGHT. ON FRIDAY...EXPECT OUTFLOW FROM THE MCS TO INCREASE LOW LEVEL MOISTURE OVER THE EASTERN PLAINS AND INTERSTATE 25 CORRIDOR. CANNOT GET VERY SPECIFIC ABOUT AMOUNT OF MOISTURE AND INSTABILITY IN THE OUTFLOW FROM MCS...BUT HUNCH IS OUTFLOW WILL BE STRONGER THAN MOST MODELS SUGGEST. IF THIS IS THE CASE...LOW LEVELS COULD BECOME MORE UNSTABLE DUE TO INCREASED MOISTURE. HOWEVER...IF THE LOW LEVELS ARE TOO CLOUDY OR COOL...ATMOSPHERE MAY BE STABLE ON THE PLAINS. DECIDED TO GO WITH SCATTERED POPS MAINLY ALONG PALMER DIVIDE AND PORTIONS OF THE EASTERN PLAINS ON FRIDAY. NAM12 HAS A POTENT AND COMPACT SHORTWAVE MOVING OVER EASTERN COLORADO FRIDAY...AND CAPES OVER PORTIONS OF THE SOUTHEAST PLAINS ARE OVER 2000 J/KG. THINK THIS MAY BE OVERDONE...BUT HIGHLIGHTS POTENTIAL FOR STRONGER CONVECTION FRIDAY. FURTHER WEST...MONSOON PLUME IS MOSTLY SUPPRESSED TO THE SOUTH...WITH ISOLATED TO SCATTERED POPS OVER THE MOUNTAINS. .SATURDAY AND SUNDAY...UPPER TROUGH REMAINS NEAR THE WEST COAST WITH THE AXIS OF THE 500 MB RIDGE OVER COLORADO. SOUTH TO SOUTHWEST FLOW ALOFT WILL START BRINGING MORE MIDDLE AND UPPER LEVEL MOISTURE INTO THE REGION. POPS INCREASE OVER THE MOUNTAINS ESPECIALLY ON SUNDAY. WEAK UPSLOPE FLOW COULD CONTINUE WITH LOW LEVEL MOISTURE REMAINING OVER THE PLAINS. .MONDAY THROUGH WEDNESDAY...GFS AND EC SUGGEST THE BEGINNING OF A PATTERN CHANGE WHICH WILL RESULT IN THE UPPER RIDGE RETROGRADING AND NORTHWEST FLOW DEVELOPING OVER THE REGION. MORE SUBTLE FEATURES WILL AFFECT THE DAY TO DAY WEATHER. CURRENT INDICATIONS ARE A DECREASE IN MID LEVEL MOISTURE BY MID WEEK FOR A DECREASED CHANCE OF DIURNAL CONVECTION OVER THE MOUNTAINS. ABUNDANT LOWER LEVEL MOISTURE ON THE PLAINS WILL GRADUALLY MOVE EAST OF THE STATE. LIKELY STILL ENOUGH MOISTURE FOR DIURNAL CONVECTION...BUT PATTERN CHANGES SUGGESTS LOWER COVERAGE WITH LESS INTENSITY. --PGW-- && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1123 PM MDT WED AUG 6 2014 VFR CONDITIONS EXPECTED OVERNIGHT AT THE TAF SITES. THERE IS THE POTENTIAL FOR SOME PATCHY IFR STRATUS TO DEVELOP ACROSS THE SOUTHEAST CO PLAINS TOWARDS 12Z...BUT SUSPECT THIS WILL BE CONFINED TO LOCATIONS ALONG/EAST OF KLHX AND WILL BE SPOTTY IN NATURE. SOUTHERLY WINDS WILL INCREASE THURSDAY AFTERNOON AND A DISTURBANCE WILL BRING SCATTERED THUNDERSTORMS TO THE MOUNTAINS WHICH WILL DRIFT OFF INTO THE ADJACENT VALLEYS AND LOWER ELEVATIONS DURING THE AFTERNOON AND EVENING. A FEW STORMS COULD BE STRONG...PARTICULARLY ALONG AND EAST OF I-25 WITH GUSTY WINDS UP TO 50 MPH...BRIEF MVFR CONDITIONS IN +TSRA...AND POSSIBLY SOME SMALL HAIL. TAFS CARRY ONLY VCTS FOR NOW AS TIMING AND COVERAGE OF THUNDERSTORMS AS THEY MOVE OFF THE MOUNTAINS IS STILL IN QUESTION. ERRATIC GUSTY WINDS WILL BE POSSIBLE FOR KCOS AND KPUB DUE TO OUTFLOW FROM THUNDERSTORMS...EVEN IF THEY DO NOT DIRECTLY IMPACT THE TERMINAL. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...HODANISH LONG TERM...PGW AVIATION...KT
AREA FORECAST DISCUSSION
NWS ALBANY NY
154 AM EDT THU AUG 7 2014 .SYNOPSIS... A WEAK FRONTAL BOUNDARY WILL SETTLE SOUTH OF THE REGION TONIGHT. ANOTHER COLD FRONT AND STRONG UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING THURSDAY...PRODUCING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD EASTWARD ACROSS THE GREAT LAKES AND INTO THE NORTHEAST FRIDAY INTO THE WEEKEND...WITH ABUNDANT SUNSHINE AND SEASONABLY WARM TEMPERATURES. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 118 AM EDT...INCREASED POPS ACROSS THE SOUTHERN ADIRONDACKS AND LAKE GEORGE REGION OVERNIGHT...AS RADAR RETURNS DETECTING SHOWERS HAVE ALREADY DEVELOP IN THIS AREA ASSOCIATED WITH A SHORT WAVE DISTURBANCE ROUNDING THE BASE OF AN UPPER LEVEL LOW BECOMING ESTABLISHED ACROSS SOUTHERN QUEBEC AND THE NORTHEAST CONUS. CLOUDS ARE ALSO INCREASING QUICKLY...SO ADJUSTED SKY GRIDS AND TEMPS BASED ON LATEST OBS AND TRENDS. HRRR INDICATING THE BULK OF THE SHOWERS SHOULD STAY NORTH OF THE CAPITAL REGION...IMPACTING THE SARATOGA AND GLENS FALLS WITH SCATTERED SHOWERS. THIS DISTURBANCE SHOULD BE EAST OF THE REGION SHORTLY AFTER SUNRISE. TEMPERATURES COOLED QUICKLY EARLIER THIS EVENING...BUT WILL START TO LEVEL OFF DUE TO THE INCREASING CLOUDS. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/... THURSDAY...A STRONG MID/UPPER LEVEL IMPULSE AND COLD POOL WILL TRANSLATE SOUTHEAST ACROSS THE REGION DURING THE MID MORNING THROUGH EARLY AFTERNOON HOURS. AS WAS THE CASE LAST WEEK...DEPENDING ON THE DEGREE OF SFC HEATING...SOME RATHER HEALTHY INSTABILITY COULD DEVELOP IN ADVANCE OF THIS APPROACHING FEATURE TO ALLOW FOR ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...SOME OF WHICH COULD BE STRONG...CONTAINING GUSTY WINDS AND AT LEAST SMALL HAIL. SHOULD TEMPERATURES REACH THE UPPER 70S...AND DEWPOINTS REACH OR EXCEED THE MID 50S...THEN CAN NOT RULE OUT ISOLATED SEVERE THUNDERSTORMS WITH HAIL/WIND. AT THIS TIME...IT APPEARS THAT THE BEST OVERLAP OF INSTABILITY...AND FORCING WILL BE FOR AREAS MAINLY N AND E OF ALBANY...ACROSS THE UPPER HUDSON VALLEY...LAKE GEORGE/SARATOGA REGION...AND SOUTHERN VT. WILL INCLUDE MENTION OF SMALL HAIL/GUSTY WINDS AT THIS TIME...BUT FUTURE TRENDS WILL NEED TO BE WATCHED IN CASE MORE SUNSHINE AND INSTABILITY OCCURS...AND RESULTS IN STRONGER TSTMS. MAX TEMPS SHOULD REACH THE MID/UPPER 70S IN VALLEY AREAS...AND UPPER 60S/LOWER 70S ACROSS HIGHER TERRAIN. DEWPOINTS SHOULD MAINLY BE IN THE LOWER/MID 50S. THU NT...ANY LINGERING SHOWERS ACROSS SOUTHERN VT/NW MA AND THE UPPER HUDSON VALLEY SHOULD TAPER OFF QUICKLY IN THE EVENING. THEN...EXPECT CLEAR TO PARTLY CLOUDY SKIES. SOME PATCHY FOG COULD ONCE AGAIN DEVELOP...ESP IN ANY AREAS WHICH RECEIVE RAINFALL. MIN TEMPS SHOULD INTO THE LOWER 50S IN MOST AREAS...WITH SOME 45-50 ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS AND HIGHER TERRAIN ACROSS WESTERN NEW ENGLAND. FRI...ADDITIONAL SHORTWAVE ENERGY PIVOTING SOUTHWARD ON THE WESTERN PERIPHERY OF THE SLOWLY DEPARTING TROUGH MAY ALLOW FOR SOME CLOUDS...AND PERHAPS ISOLATED SHOWERS/SPRINKLES ACROSS HIGHER ELEVATIONS OF THE SOUTHERN ADIRONDACKS AND VT. ELSEWHERE...OTHER THAN SOME PASSING CLOUDS...EXPECT GENERALLY FAIR CONDITIONS...WITH MAX TEMPS GENERALLY REACHING THE UPPER 70S TO AROUND 80 FOR VALLEYS...AND UPPER 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FRI NT...GENERALLY CLEAR AND COOL...WITH MIN TEMPS FALLING INTO THE LOWER/MID 50S IN MOST AREAS...EXCEPT FOR SOME 40S ACROSS THE SOUTHERN ADIRONDACKS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE WEATHER WILL BE PRECIPITATION-FREE THROUGH THE WEEKEND AND INTO THE BEGINNING OF NEXT WEEK...THEN SHOWERS AND THUNDERSTORMS BECOME INCREASINGLY POSSIBLE INTO MID-WEEK. HIGH PRESSURE GRADUALLY DRIFTS OFF THE NEW ENGLAND COAST THROUGH THE WEEKEND. WEAK LOW PRESSURE OFF THE CAROLINAS COAST WILL BUILD A TROF BACK ACROSS WESTERN NEW ENGLAND BY WEDNESDAY. WE WILL SEE A SLIGHT AND GRADUAL INCREASE IN RELATIVE HUMIDITIES EACH DAY. HIGH TEMPERATURES SATURDAY THROUGH MONDAY WILL BE IN THE MID 70S TO MID 80S RANGE. AN OBVIOUS INCREASE IN CLOUD COVER WILL KEEP TUESDAY/S HIGHS RANGING FROM AROUND 70 DEGREES IN THE HIGH PEAKS... TO AROUND 80 DEGREES DOWN THE HUDSON VALLEY. WEDNESDAY WILL BE COOLER STILL FOR MOST LOCATIONS AS A COLD FRONT SLIDES INTO THE REGION FROM THE NORTHWEST. NORMAL HIGHS IN ALBANY ARE IN THE LOWER 80S...NORMAL LOWS...AROUND 60 DEGREES. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... ALREADY HAVE SOME SHOWERS MOVING ACROSS THE NORTHERN PORTION OF THE FORECAST AREA ASSOCIATED WITH AN APPROACHING SHORT WAVE MOVING THROUGH THE UPPER LEVEL TROUGH OVER QUEBEC AND THE NORTHEAST. THESE SHOWERS SHOULD IMPACT KGFL EARLY IN THE TAF PERIOD. CLOUD COVER SHOULD THIN OUT BEFORE SUNRISE SO SOME RADIATIONAL FOG MAY DEVELOP AT KGFL...KPSF AND KPOU. FOG IS NOT EXPECTED AT KALB AS A LIGHT WEST WIND IS EXPECTED TO CONTINUE. THE UPPER LEVEL TROUGH WILL DEEPEN OVER THE REGION AS THE SHORT WAVE ROTATES THROUGH THE BASE OF THE TROUGH. SCATTERED CONVECTION IS EXPECTED TODAY ESPECIALLY FROM LATE MORNING INTO THE AFTERNOON AS THE COLD POOL MOVES OVER THE REGION WITH 500 MB TEMPERATURES DROPPING TO -17 TO -19 DEGREES CELSIUS IN CONJUNCTION WITH THE HEATING OF THE DAY. HAVE ADDRESSED THREAT WITH A VCSH IN TAFS. MAINLY VFR CONDITIONS ARE EXPECTED...WITH MVFR AND BRIEF IFR CONDITIONS WITH ANY CONVECTION. CONVECTION WILL DIMINISH AS THE SHORT WAVE AND COLD POOL MOVE OFF TO THE EAST LATER THIS AFTERNOON. LIGHT WEST WINDS AT KALB...OTHERWISE CALM WINDS CONTINUE EARLY THIS MORNING. NORTHWEST TO NORTHERLY WIND DEVELOP AFTER SUNRISE WITH GUSTS INTO THE TEENS AT KALB AND KPSF DURING THE AFTERNOON. WINDS WILL DIMINISH EARLY IN THE EVENING. OUTLOOK... THU NIGHT-MON: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A WEAK FRONTAL BOUNDARY WILL SETTLE SOUTH OF THE REGION TONIGHT. ANOTHER COLD FRONT AND STRONG UPPER LEVEL TROUGH WILL CROSS THE REGION ON THURSDAY...PRODUCING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD EASTWARD ACROSS THE GREAT LAKES AND INTO THE NORTHEAST FRIDAY INTO THE WEEKEND...WITH ABUNDANT SUNSHINE AND SEASONABLY WARM TEMPERATURES. RH VALUES WILL INCREASE TO AROUND 85 TO 100 PERCENT TONIGHT..WITH SOME DEW FORMATION POSSIBLE. MIN RH VALUES ON THURSDAY AFTERNOON ARE EXPECTED TO BE BETWEEN 40 AND 55 PERCENT...THEN RECOVER TO 90-100 PERCENT FOR THU NT/FRI AM WITH WIDESPREAD DEW FORMATION LIKELY. NORTHWEST TO NORTH WINDS WILL DECREASE TO LESS THAN 5 MPH TONIGHT...THEN BECOME WEST TO NORTHWEST AND INCREASE TO 10-20 MPH FOR THU AFTERNOON. WINDS WILL BE VARIABLE IN DIRECTION...AND MUCH STRONGER IN AND NEAR ANY THUNDERSTORMS. && .HYDROLOGY... AFTER ANY EARLY EVENING SHOWERS DIMINISH...GENERALLY DRY CONDITIONS ARE EXPECTED OVERNIGHT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP ON THURSDAY...AS A STRONG UPPER LEVEL DISTURBANCE MOVES THROUGH. SOME OF THE STORMS MAY PRODUCE LOCALLY HEAVY RAINFALL AND MINOR FLOODING OF URBAN...POOR DRAINAGE AND LOW LYING AREAS. DRY WEATHER IS THEN EXPECTED FROM FRIDAY THROUGH THE WEEKEND WITH HIGH PRESSURE IN CONTROL. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...KL/GJM NEAR TERM...KL/JPV SHORT TERM...KL LONG TERM...ELH AVIATION...IAA FIRE WEATHER...KL/JPV HYDROLOGY...KL/JPV
AREA FORECAST DISCUSSION
NWS ALBANY NY
118 AM EDT THU AUG 7 2014 .SYNOPSIS... A WEAK FRONTAL BOUNDARY WILL SETTLE SOUTH OF THE REGION TONIGHT. ANOTHER COLD FRONT AND STRONG UPPER LEVEL DISTURBANCE WILL CROSS THE REGION DURING THURSDAY...PRODUCING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD EASTWARD ACROSS THE GREAT LAKES AND INTO THE NORTHEAST FRIDAY INTO THE WEEKEND...WITH ABUNDANT SUNSHINE AND SEASONABLY WARM TEMPERATURES. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 118 AM EDT...INCREASED POPS ACROSS THE SOUTHERN ADIRONDACKS AND LAKE GEORGE REGION OVERNIGHT...AS RADAR RETURNS DETECTING SHOWERS HAVE ALREADY DEVELOP IN THIS AREA ASSOCIATED WITH A SHORT WAVE DISTURBANCE ROUNDING THE BASE OF AN UPPER LEVEL LOW BECOMING ESTABLISHED ACROSS SOUTHERN QUEBEC AND THE NORTHEAST CONUS. CLOUDS ARE ALSO INCREASING QUICKLY...SO ADJUSTED SKY GRIDS AND TEMPS BASED ON LATEST OBS AND TRENDS. HRRR INDICATING THE BULK OF THE SHOWERS SHOULD STAY NORTH OF THE CAPITAL REGION...IMPACTING THE SARATOGA AND GLENS FALLS WITH SCATTERED SHOWERS. THIS DISTURBANCE SHOULD BE EAST OF THE REGION SHORTLY AFTER SUNRISE. TEMPERATURES COOLED QUICKLY EARLIER THIS EVENING...BUT WILL START TO LEVEL OFF DUE TO THE INCREASING CLOUDS. && .SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY NIGHT/... THURSDAY...A STRONG MID/UPPER LEVEL IMPULSE AND COLD POOL WILL TRANSLATE SOUTHEAST ACROSS THE REGION DURING THE MID MORNING THROUGH EARLY AFTERNOON HOURS. AS WAS THE CASE LAST WEEK...DEPENDING ON THE DEGREE OF SFC HEATING...SOME RATHER HEALTHY INSTABILITY COULD DEVELOP IN ADVANCE OF THIS APPROACHING FEATURE TO ALLOW FOR ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP...SOME OF WHICH COULD BE STRONG...CONTAINING GUSTY WINDS AND AT LEAST SMALL HAIL. SHOULD TEMPERATURES REACH THE UPPER 70S...AND DEWPOINTS REACH OR EXCEED THE MID 50S...THEN CAN NOT RULE OUT ISOLATED SEVERE THUNDERSTORMS WITH HAIL/WIND. AT THIS TIME...IT APPEARS THAT THE BEST OVERLAP OF INSTABILITY...AND FORCING WILL BE FOR AREAS MAINLY N AND E OF ALBANY...ACROSS THE UPPER HUDSON VALLEY...LAKE GEORGE/SARATOGA REGION...AND SOUTHERN VT. WILL INCLUDE MENTION OF SMALL HAIL/GUSTY WINDS AT THIS TIME...BUT FUTURE TRENDS WILL NEED TO BE WATCHED IN CASE MORE SUNSHINE AND INSTABILITY OCCURS...AND RESULTS IN STRONGER TSTMS. MAX TEMPS SHOULD REACH THE MID/UPPER 70S IN VALLEY AREAS...AND UPPER 60S/LOWER 70S ACROSS HIGHER TERRAIN. DEWPOINTS SHOULD MAINLY BE IN THE LOWER/MID 50S. THU NT...ANY LINGERING SHOWERS ACROSS SOUTHERN VT/NW MA AND THE UPPER HUDSON VALLEY SHOULD TAPER OFF QUICKLY IN THE EVENING. THEN...EXPECT CLEAR TO PARTLY CLOUDY SKIES. SOME PATCHY FOG COULD ONCE AGAIN DEVELOP...ESP IN ANY AREAS WHICH RECEIVE RAINFALL. MIN TEMPS SHOULD INTO THE LOWER 50S IN MOST AREAS...WITH SOME 45-50 ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS AND HIGHER TERRAIN ACROSS WESTERN NEW ENGLAND. FRI...ADDITIONAL SHORTWAVE ENERGY PIVOTING SOUTHWARD ON THE WESTERN PERIPHERY OF THE SLOWLY DEPARTING TROUGH MAY ALLOW FOR SOME CLOUDS...AND PERHAPS ISOLATED SHOWERS/SPRINKLES ACROSS HIGHER ELEVATIONS OF THE SOUTHERN ADIRONDACKS AND VT. ELSEWHERE...OTHER THAN SOME PASSING CLOUDS...EXPECT GENERALLY FAIR CONDITIONS...WITH MAX TEMPS GENERALLY REACHING THE UPPER 70S TO AROUND 80 FOR VALLEYS...AND UPPER 60S TO LOWER 70S ACROSS HIGHER ELEVATIONS. FRI NT...GENERALLY CLEAR AND COOL...WITH MIN TEMPS FALLING INTO THE LOWER/MID 50S IN MOST AREAS...EXCEPT FOR SOME 40S ACROSS THE SOUTHERN ADIRONDACKS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE WEATHER WILL BE PRECIPITATION-FREE THROUGH THE WEEKEND AND INTO THE BEGINNING OF NEXT WEEK...THEN SHOWERS AND THUNDERSTORMS BECOME INCREASINGLY POSSIBLE INTO MID-WEEK. HIGH PRESSURE GRADUALLY DRIFTS OFF THE NEW ENGLAND COAST THROUGH THE WEEKEND. WEAK LOW PRESSURE OFF THE CAROLINAS COAST WILL BUILD A TROF BACK ACROSS WESTERN NEW ENGLAND BY WEDNESDAY. WE WILL SEE A SLIGHT AND GRADUAL INCREASE IN RELATIVE HUMIDITIES EACH DAY. HIGH TEMPERATURES SATURDAY THROUGH MONDAY WILL BE IN THE MID 70S TO MID 80S RANGE. AN OBVIOUS INCREASE IN CLOUD COVER WILL KEEP TUESDAY/S HIGHS RANGING FROM AROUND 70 DEGREES IN THE HIGH PEAKS... TO AROUND 80 DEGREES DOWN THE HUDSON VALLEY. WEDNESDAY WILL BE COOLER STILL FOR MOST LOCATIONS AS A COLD FRONT SLIDES INTO THE REGION FROM THE NORTHWEST. NORMAL HIGHS IN ALBANY ARE IN THE LOWER 80S...NORMAL LOWS...AROUND 60 DEGREES. && .AVIATION /05Z THURSDAY THROUGH MONDAY/... EXPECT VFR CONDITIONS THROUGH MOST OF THE TAF PERIOD ENDING AT 00Z FRIDAY AT THE KGFL/KLB/KPOU/KPSF TAF SITES. THE EXCEPTION WILL BE POSSIBLE MVFR/IFR CONDITIONS DUE TO LATE NIGHT FOG FORMATION AT KGFL/KPSF/KPOU. THE FOG FORMATION IS STILL NOT CERTAIN AT THIS TIME DUE TO THE DRY AIRMASS OVER THE REGION...AND SOME CLOUDS THAT WILL MOVE IN LATER TONIGHT...SO HAVE ONLY FORECAST TEMPO GROUP FOR FOG BETWEEN 06Z AND 11Z. NORTHWEST TO NORTHERLY WIND AT 5 TO 10 MPH THIS EVENING WILL BECOME LIGHT AND VARIABLE OVERNIGHT...THEN NORTHWEST TO NORTHERLY ON THURSDAY AT 8 TO 10 KTS WITH GUSTS UP TO 15 KTS. OUTLOOK... THURSDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY: NO OPERATIONAL IMPACT. NO SIG WX. SUNDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... A WEAK FRONTAL BOUNDARY WILL SETTLE SOUTH OF THE REGION TONIGHT. ANOTHER COLD FRONT AND STRONG UPPER LEVEL TROUGH WILL CROSS THE REGION ON THURSDAY...PRODUCING ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS. HIGH PRESSURE WILL THEN BUILD EASTWARD ACROSS THE GREAT LAKES AND INTO THE NORTHEAST FRIDAY INTO THE WEEKEND...WITH ABUNDANT SUNSHINE AND SEASONABLY WARM TEMPERATURES. RH VALUES WILL INCREASE TO AROUND 85 TO 100 PERCENT TONIGHT..WITH SOME DEW FORMATION POSSIBLE. MIN RH VALUES ON THURSDAY AFTERNOON ARE EXPECTED TO BE BETWEEN 40 AND 55 PERCENT...THEN RECOVER TO 90-100 PERCENT FOR THU NT/FRI AM WITH WIDESPREAD DEW FORMATION LIKELY. NORTHWEST TO NORTH WINDS WILL DECREASE TO LESS THAN 5 MPH TONIGHT...THEN BECOME WEST TO NORTHWEST AND INCREASE TO 10-20 MPH FOR THU AFTERNOON. WINDS WILL BE VARIABLE IN DIRECTION...AND MUCH STRONGER IN AND NEAR ANY THUNDERSTORMS. && .HYDROLOGY... AFTER ANY EARLY EVENING SHOWERS DIMINISH...GENERALLY DRY CONDITIONS ARE EXPECTED OVERNIGHT. ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS WILL DEVELOP ON THURSDAY...AS A STRONG UPPER LEVEL DISTURBANCE MOVES THROUGH. SOME OF THE STORMS MAY PRODUCE LOCALLY HEAVY RAINFALL AND MINOR FLOODING OF URBAN...POOR DRAINAGE AND LOW LYING AREAS. DRY WEATHER IS THEN EXPECTED FROM FRIDAY THROUGH THE WEEKEND WITH HIGH PRESSURE IN CONTROL. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...KL/GJM NEAR TERM...KL/JPV SHORT TERM...KL LONG TERM...ELH AVIATION...GJM FIRE WEATHER...KL/JPV HYDROLOGY...KL/JPV
AREA FORECAST DISCUSSION
NWS MIAMI FL
322 AM EDT THU AUG 7 2014 .DISCUSSION... EARLY WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW NORTH OF MAINE...WITH THE UPPER TROUGH AXIS EXTENDING SOUTHWARD ACROSS THE COAST OF THE MID ATLANTIC AND INTO THE SOUTHEAST STATES. WEAK HIGH PRESSURE STRETCHED ACROSS SOUTH FLORIDA AND THE WESTERN ATLANTIC. A WEAK UPPER LEVEL DISTURBANCE OVER NORTHERN FLORIDA WILL DROP SLOWLY SOUTHWARD TOWARDS CENTRAL FLORIDA AND THE LAKE REGION THROUGH THE DAY. AT THE SURFACE...THE RIDGE IS SLIGHTLY WEAKER...BUT THE FLOW ABOVE SURFACE WILL BE LIGHT OUT OF THE WEST. THIS WILL ALLOW THE GULF COAST SEA BREEZE TO PUSH IN QUICKLY...WITH SHOWERS AND STORMS DEVELOPING ACROSS THE WEST EARLIER IN THE DAY...WITH OUTFLOW BOUNDARIES ALLOWING STORMS TO DEVELOP ALONG IN THE INTERIOR...AND THEN TOWARDS THE EAST COAST AS OUTFLOW BOUNDARIES INTERACT WITH THE SEA BREEZE. WITH THE WEAK UPPER DISTURBANCE...A MORE ACTIVE DAY OVERALL IS EXPECTED. A WEAK TROPICAL WAVE IS FORECAST TO MOVE ACROSS EASTERN CUBA TODAY. THE NORTHERN FRINGES OF THE WAVE COULD MOVE ACROSS SOUTH FLORIDA ON FRIDAY AND FRIDAY NIGHT...WHICH WOULD BRING ANOTHER CONVECTIVELY ACTIVE DAY FOR THE REGION. THE MID LEVEL RIDGE ACROSS SOUTH FLORIDA TODAY WILL BUILD NORTHWARD OVER CENTRAL FLORIDA FRIDAY INTO THE WEEKEND AND STRENGTHEN...ALLOWING A SOUTHEASTERLY FLOW TO DEVELOP. STREAMER SHOWERS MAY RETURN TO THE ATLANTIC WATERS AND EAST COAST METRO AREAS EACH MORNING...WITH SCATTERED TO NUMEROUS SEA BREEZE ACTIVITY IN THE AFTERNOON. MODEL GUIDANCE HAS PUSHED BACK THE ARRIVAL OF THE DRY AIR UNTIL SUNDAY NIGHT OR MONDAY. HOWEVER...AN OVERALL DRYING TREND WILL BEGIN ON SUNDAY ACROSS DEEP SOUTH FLORIDA AND THEN ACROSS THE REST OF THE REGION MONDAY THROUGH THE MIDDLE OF THE WEEK. TEMPERATURES ARE FORECAST TO BE NEAR NORMAL THROUGH THE PERIOD. && .AVIATION... A WEAK UPPER LEVEL DISTURBANCE...IN PART RELATED TO A SLIGHTLY DEEPENING SURFACE TROUGH ALONG THE SOUTHEAST COAST...WILL SLOWLY SINK SOUTH TODAY. THE SURFACE RIDGE OVER SOUTH FLORIDA YESTERDAY WILL WEAKEN EVER SO SLIGHTLY. THUS...WINDS WILL BE SOMEWHAT STRONGER FROM THE SW AND W THIS AFTERNOON. INITIALLY THIS MAY LEAD TO EARLIER AND MORE NUMEROUS STORMS THAN YESTERDAY NEAR KAPF. SO VCTS GROUP WAS MOVED UP A FEW HOURS THERE. ALSO...A SLIGHTLY STRONGER SW TO W WIND AND MORE DEVELOPMENT ALONG THE GULF COAST MAY PRODUCE QUICKER OR MORE NUMEROUS OUTFLOW BOUNDARIES...THAT CAN INTERACT WITH A SLIGHTLY STRONGER EAST COAST SEA BREEZE. IN CONCLUSION...VCTS WAS INCLUDED AT ALL TAF SITES...AND THE FEELING IS THAT COVERAGE WILL BE BETTER THAN YESTERDAY...WHICH CAN LEAD TO A SLIGHTLY GREATER CHANCE OF BRIEF IFR CONDS UNDER THE STRONGEST STORMS. && .MARINE... ATLANTIC WINDS ARE FORECAST TO SLOWLY TRANSITION TO A MORE SOUTHEASTERLY DIRECTION TODAY THROUGH THE WEEKEND...BUT REMAINING LIGHT. LATEST GUIDANCE INDICATES THAT LIGHT WESTERLY WINDS COULD PERSIST ACROSS PORTIONS OF THE GULF WATERS THURSDAY INTO FRIDAY. OTHERWISE...WINDS ARE FORECAST TO BE 10 KNOTS OR LESS THROUGH THE UPCOMING WEEKEND AND REGIONAL SEAS LESS THAN TWO FEET THROUGH THAT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 91 77 90 77 / 50 20 50 20 FORT LAUDERDALE 91 78 90 78 / 50 20 50 20 MIAMI 91 78 90 77 / 50 20 50 20 NAPLES 91 77 90 76 / 40 10 30 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...84/AK LONG TERM....84/AK AVIATION...21/KM
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
603 AM EDT THU AUG 7 2014 .SYNOPSIS... A COLD FRONT WILL MOVE INTO THE FORECAST AREA TODAY AND STALL. THE FRONT WILL REMAIN IN THE AREA THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... THE COLD FRONT SLOWLY PUSHING SOUTHWARD AND INTO THE FORECAST AREA TODAY WILL STALL TONIGHT. DESPITE CONVERGENCE ASSOCIATED WITH THE FRONT...THE THUNDERSTORM CHANCE IS LOW BECAUSE OF A LACK OF DEEP MOISTURE AND UPPER-LEVEL LIFT. THE NAM AND GFS DISPLAY SHALLOW MOISTURE WITH UPPER-LEVEL RIDGING. THE NAM AND GFS MOS HAVE POPS LESS THAN 20 PERCENT. THE 07Z HRRR DISPLAYS ISOLATED COVERAGE NEARING THE CSRA TOWARD 600 PM. THE 00Z SPC WRF SHOWS JUST ISOLATED COVERAGE MAINLY DURING THE EVENING. WE WILL GET OFF TO A WARM START AND SATELLITE TRENDS SHOW LITTLE CLOUDINESS IMMEDIATELY UPSTREAM. IT SHOULD BE HOT UNDER MOSTLY SUNNY SKIES. THE GUIDANCE CONSENSUS SUPPORTS HIGHS IN THE MIDDLE AND UPPER 90S. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... THE NAM AND GFS INDICATE AN INCREASE IN MOISTURE ASSOCIATED WITH CONVERGENCE NEAR THE STALLED FRONT AND MOISTURE MOVING INTO THE AREA FROM THE WEST AS THE UPPER RIDGE FLATTENS. THE GUIDANCE CONSENSUS SUPPORTS CHANCE POPS. THE TEMPERATURE GUIDANCE WAS CLOSE. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE GFS AND ECMWF DISPLAY A STALLED FRONT WITH SIGNIFICANT MOISTURE IN THE FORECAST AREA THROUGH THE MEDIUM-RANGE PERIOD. THE GFS...ECMWF...AND EKE MOS POPS GENERALLY RANGE FROM 30 TO 60 PERCENT WITH THE HIGHER CHANCES SATURDAY AND SUNDAY. THE MODELS INDICATE PRECIPITABLE WATER OVER 2 INCHES SATURDAY AND SUNDAY SO HEAVY RAIN MAY OCCUR. THE MOS TEMPERATURES ARE CLOSE TO CLIMATOLOGY DURING THE PERIOD. && .AVIATION /10Z THURSDAY THROUGH MONDAY/... VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. JUST A FEW HIGH AND MID-LEVEL CLOUDS ACROSS THE AREA EARLY THIS MORNING. GIVEN THE LATEST OBSERVATIONAL TRENDS...WILL ONLY MENTION MVFR FOG EARLY THIS MORNING AT AGS. A FEW MORE CLOUDS AHEAD OF A WEAK FRONTAL SYSTEM WILL BEGIN MOVING INTO THE AREA BY THE LATE AFTERNOON. WINDS WILL BE LIGHT AND VARIABLE THROUGH 14Z...THEN BECOME NORTHWESTERLY AROUND 6-8 KNOTS INTO THE AFTERNOON HOURS. WINDS SHOULD SHIFT TO THE EAST BY EARLY THIS EVENING...THEN GOING LIGHT AND VARIABLE BY LATE EVENING. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE LATE FRIDAY THROUGH MONDAY IN SHOWERS AND THUNDERSTORMS AS A LOW PRESSURE SYSTEM SLOWLY CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS DES MOINES IA
351 AM CDT THU AUG 7 2014 .SHORT TERM /TODAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 DIFFICULT FORECAST TODAY AS THE MODELS REALLY DO NOT HAVE A GOOD HANDLE ON WHAT IS GOING ON. ALOFT A SHORTWAVE IS SHIFTING ACROSS NORTHERN/CENTRAL MISSOURI. THERE IS GOOD MOISTURE TRANSPORT INTO THIS AREA INTERSECTING A FRONTAL BOUNDARY. HOWEVER THE MOISTURE IS HAVING A TOUGH TIME REACHING IOWA AS IT IS FEEDING THE STORMS IN MISSOURI. AS A RESULT WE HAVE NOT RECEIVED THE HEAVY RAINFALL PREVIOUSLY THOUGHT ACROSS FAR SOUTHERN IOWA THUS THE FLASH FLOOD WATCH WILL BE DROPPED WITH THE MORNING ISSUANCE. AT THE SURFACE...LOW PRESSURE OVER NORTHERN MISSOURI IS TIED TO THE AFOREMENTIONED FRONTAL BOUNDARY AND THIS IS PROGGED TO SLOWLY LIFT TO THE NORTHEAST TODAY. THE QUESTION IS HOW FAR NORTHEAST WILL IT GET. LATEST PROGS BARELY LIFT IT INTO SOUTHEAST IOWA THUS THE HEAVY RAINFALL POTENTIAL SHOULD STAY SOUTH AND EAST OF IOWA WHERE THE BETTER INSTABILITY WILL REMAIN. THERE WILL HOWEVER BE SOME WEAK KINEMATIC FORCING OVER IOWA TODAY THUS THE POTENTIAL FOR SHOWER/ISOLATED THUNDERSTORMS WILL REMAIN OVER MUCH OF THE CWA TODAY UNTIL THE SHORTWAVE AND SURFACE LOW PUSH EAST. AS FOR QPF...THE 06Z NAM WAS BETTER AT WITH ITS QPF FORECAST THAN THE 00Z RUN BUT IT SEEMS TO BE TIED TOO MUCH TO THE FORCING AND THE PAST COUPLE OF NIGHTS THE HEAVIER PRECIP WAS TIED MORE THE TO INSTABILITY AXIS. THE HOPWRF ALSO WAS ALSO PRETTY BULLISH ON PRECIP WHILE THE HRRR...WHICH HAD THE BEST HANDLE ON ONGOING PRECIP...SHOWED THE PRECIP TIED TO THE LOW AND FRONTAL BOUNDARY MAINLY IN MO WITH SCT PRECIP MORE OVER EASTERN IOWA INTO THE EASTERN PORTION OF OUR CWA. I LIKED THE HRRR THE BEST AND PREFER ITS SOLUTION BUT DID BLEND POPS WITH THE HOPWRF AND NEIGHBORING OFFICES. I KEPT THE HIGHEST POPS IN THE SOUTHEAST FROM LATE MORNING INTO THE AFTERNOON WITH CHANCE OR SLIGHT CHANCE POPS ELSEWHERE. NORTHEASTERN IOWA WAS SPARED FROM PRECIP YESTERDAY IN LARGE PART FROM THE HIGH PARKED TO THE NORTHEAST BUT AS THE LOW SHIFTS NORTHEAST THE SURFACE HIGH WILL PUSH EAST AND LOSE MUCH OF ITS INFLUENCE ON NORTHEASTERN PORTIONS OF THE CWA. I DID PUT A PERIOD OF CHANCE POPS IN FOR THE AFTERNOON BUT POP CHANCES SHOULD BE LOWEST IN THIS AREA. PATCHY FOG HAS DEVELOPED OVER MUCH OF THE CWA AND THIS WILL LIKELY HANG AROUND THROUGH A FAIR PART OF THE MORNING. SOUNDINGS ARE SHOWING A PERSISTENT EASTERLY COMPONENT TO THE WIND AND DEEP MOISTURE OVER CENTRAL IOWA THROUGH AT LEAST 15Z. TEMPS WILL ALSO BE COOLER TODAY WITH THE CLOUD COVER AND SCATTERED SHOWERS/STORMS. GENERALLY DROPPED HIGHS ACROSS THE CENTRAL SECTIONS AND KEPT THE NORTHEAST WARMER PRIMARILY DUE TO HIGHER CLOUD HEIGHTS...LOWER PRECIP CHANCES AND QPF. .LONG TERM /TONIGHT THROUGH WEDNESDAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 FORCING WILL PERSIST MAINLY IN THE EAST AND NORTH THIS EVENING WHERE LIGHT SCATTERED SHOWERS MAY LINGER. HOWEVER...THE FORCING WILL SUBSIDE DURING THE NIGHT WITH THE THREAT OF PRECIPITATION DIMINISHING OVERNIGHT. THE STATE WILL CONTINUE TO SEE WESTERLY FLOW ALOFT WITH EASTERLY SURFACE FLOW AS THE SURFACE FRONT REMAINS SOUTH AND WEST OF IOWA AND WEAK RIDGING SLIDING TO THE NORTH. THE RELATIVELY MOIST EASTERLY FLOW WILL LIKELY KEEP A GOOD AMOUNT OF CLOUDINESS AROUND ON FRIDAY INTO SATURDAY. THIS IS EXPECTED TO KEEP DIURNAL RANGES RELATIVELY LOW WITH DAYTIME HIGHS REMAINING BELOW NORMAL WITH LIMITED INSOLATION. DESPITE THE MOIST LOW LEVELS DURING THIS TIME...FORCING WILL BE WEAK OR NON-EXISTENT AND THEREFORE PRECIPITATION IS NOT EXPECTED ON FRIDAY OR SATURDAY. THE NEXT SYSTEM BEGINS TO APPROACH LATE IN THE WEEKEND BUT THE BULK OF FORCING WILL REMAIN TO THE NORTH. THIS WILL LIMIT THUNDERSTORMS CHANCES AND ANY STORMS THAT DO FORM WILL LIKELY BE SOMEWHAT UNORGANIZED AS SHEAR WILL REMAIN WEAK. THE REMAINDER OF THE EXTENDED APPEARS RELATIVELY DRY AFTER MONDAY WITH SOME MODERATION IN TEMPERATURES AS THE EASTERLY FLOW WEAKENS. && .AVIATION...07/06Z ISSUED AT 1139 PM CDT WED AUG 6 2014 SURFACE LOW OVER KANSAS THIS EVENING WILL SLOWLY MOVE EAST THROUGH MISSOURI ON THURSDAY. IOWA WILL REMAIN IN DEEP EASTERLY FLOW NORTH OF THE SYSTEM. MODEL SOUNDINGS SUGGEST THERE WILL BE PLENTY OF DEEP MOISTURE AVAILABLE. WILL FORECAST GENERALLY MVFR TO VFR CIGS THROUGH THE PERIOD. THERE WILL LIKELY BE SHOWERS...BUT KEPT THEM VICINITY AS OPPOSED TO PUTTING THEM DIRECTLY IN THE TAFS. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...FAB LONG TERM...COGIL AVIATION...JOHNSON
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1144 PM CDT WED AUG 6 2014 .UPDATE... ISSUED AT 1139 PM CDT WED AUG 6 2014 DEEP CONVECTION WILL LIKELY STAY SOUTH OF IOWA TONIGHT. HOWEVER...SCATTERED SHOWERS WITH A FEW THUNDERSTORMS WILL CONTINUE OVER SOUTH CENTRAL IOWA. SHOWERS WILL BE EFFICIENT RAIN PRODUCERS AND MAY RESULT IN LOCALIZED RUNOFF ISSUES. WILL LEAVE FLASH FLOOD IN EFFECT THROUGH THE NIGHT. && .SHORT TERM /TONIGHT/... ISSUED AT 328 PM CDT WED AUG 6 2014 ANOTHER ROUND OF HEAVY RAINFALL IS POSSIBLE FOR THE CWA TONIGHT...MAINLY SOUTHERN PORTIONS. TWO SHORTWAVES...PRESENTLY MOVING THROUGH SE SOUTH DAKOTA AND NORTH CENTRAL KS...WILL HELP PROVIDE THE LARGE-SCALE FORCING FOR OVERNIGHT PCPN. LLJ IS EXPECTED TO DEVELOP AGAIN TONIGHT AND POINT INTO IA...PROVIDING AMPLE MOISTURE. PWATS ARE PROGGED TO BE INVOF THE 2.0 IN RANGE...WHICH AGAIN WILL BE AROUND +2 SD VS CLIMO. WARM CLOUD DEPTHS WILL APPROACH THE 12 KFT RANGE. MODEL FCST SOUNDINGS DO TEND TO MOISTEN THE COLUMN ACROSS SOUTHERN IA THIS EVENING...MORE SO THAN LAST NIGHT...WHICH WOULD TEND TO SUPPORT THE HEAVY RAIN THREAT TONIGHT. MODEL SOLUTIONS DO VARY ON THE AMOUNT OF FORCING AND RESULTING RAINFALL. THE NAM IS THE WETTEST AND BRINGS A RIBBON OF FORCING ALONG WITH STRONG THETA-E ADVECTION INTO SOUTH CENTRAL AND SOUTHWEST IA. THE GFS ON THE OTHER HAND IS NOT AS INTENSE THAT FAR NORTH. HAVE TENDED TO SPLIT THE DIFFERENCE...AND EXPECT THE HEAVIEST RAINFALL TONIGHT TO REMAIN SOUTH OF IA HWY 92. WILL GO WITH A FLASH FLOOD WATCH FOR SOME OF THE SOUTH CENTRAL AND SOUTHWEST IA COUNTIES ALONG AND SOUTH OF 92...GIVEN LAST NIGHT/S HEAVY RAINFALL AND RELATIVELY LOWER FLASH FLOOD GUIDANCE VALUES. ALTHOUGH AM NOT OVERLY CONCERNED ABOUT FLASH FLOOD POTENTIAL THERE...CONFIDENCE IS AROUND THE 40 TO 50 PERCENT THRESHOLD WHICH WOULD BE THE LOW-END FLASH FLOOD WATCH CRITERIA. SEVERE WEATHER POTENTIAL THIS EVENING AND OVERNIGHT IS MINIMAL BUT CANNOT BE ENTIRELY RULED OUT. ALTHOUGH CAPE VALUES HAVE INCREASED THIS AFTN IN SW IA...WITH VALUES APPROACHING THE 1000 TO 1500 J/KG RANGE. DEEP-LAYER SHEAR IS MINIMAL HOWEVER...WHICH WOULD TEND TO PRECLUDE ORGANIZED TSTM DEVELOPMENT. ATTM ANTICIPATE THE GREATEST THREAT WOULD BE HEAVY RAINFALL FROM ANY STORMS THAT DO DEVELOP. .LONG TERM /THURSDAY THROUGH WEDNESDAY/... ISSUED AT 328 PM CDT WED AUG 6 2014 MAIN CHALLENGES THIS PERIOD WILL BE MAINLY IN THE SHORTER TERM WITH EVOLUTION OF SYSTEM NEXT 24 HOURS. CURRENTLY SFC SHORT WAVE SOUTH OF THE AREA WITH BOUNDARY OVER NORTHERN MO AND WEAK TROUGH EXTENDING ACROSS NORTH CENTRAL IOWA WITH WELL DEFINED DEFORMATION AXIS AND THETAE AXIS ALOFT ACROSS THE REGION. ISENTROPIC UPGLIDE CONTINUES TO FEED THIS AREA WHERE PERSISTENT LIGHT RAIN IS FALLING. MODELS HAVENT QUITE REACHED A CONSENSUS ON THE EVENTUAL DEPARTURE OF THE SYSTEM FOR THURSDAY/THURSDAY NIGHT. THIS IS IN PART DUE TO THE PERSISTENT RIDGE AXIS WHICH EXTENDS FROM SOUTHERN CANADA TO THE SOUTHEAST US. THE GENERAL TREND HAS BEEN FOR A SLOWER TRANSITION OUT OF THE AREA THURSDAY INTO THURSDAY NIGHT. THURSDAY MORNING MOST OF THE FORCING WILL REMAIN STRONGEST ACROSS THE SOUTHEAST WITH CONTINUED UPGLIDE WRAPPING AROUND THE SYSTEM BACK INTO CENTRAL AND NORTHERN IOWA DURING THE DAY. THOUGH THE H850 MOISTURE CHANNEL WILL GRADUALLY SHIFT TO THE EAST WITH TIME...LIGHT TO MODERATE RAIN SHOULD CONTINUE THROUGH MUCH OF THE DAY THURSDAY THEN SLOWLY TAPER OFF DURING THE EVENING HOURS. BOTH THE EURO/GFS/NAM HIT THE EAST/SOUTHEAST WITH QUITE A BIT OF QPF FOCUSED BETWEEN 12-18Z USING A SLIGHTLY FARTHER NORTH TRACK OF THE H850 LOW. WPC CONTINUES TO PREFER A MORE SOUTHERN SOLUTION MORE IN LINE WITH MESO HRRR AND NMM MODELS. CURRENTLY THE SYSTEM IS TRACKING FAIRLY WELL WITH ALL MODELS BUT WITH EXPECTED MESO CONVECTION TO DEVELOP OVER NORTHERN MO THIS EVENING...TRACK EXPECTED TO END UP BEING FARTHER SOUTH THAN SYNOPTIC MODELS INDICATE AND CLOSER TO THE HRRR/NMM. FOR NOW WILL TREND TOWARD THAT SOLUTION ...IN LINE WITH WPC AS WELL BUT WILL NEED TO WATCH DURING THE EVENING SHIFT FOR ANY POTENTIAL ADJUSTMENTS FARTHER NORTH. ANY DEVIATION NORTH WOULD RESULT IN RAINFALL TOTALS BEING HIGHER IN THE FORECAST AREA THURSDAY. EVENTUALLY THE SYSTEM BECOMES SHEARED OUT AND WEAKENS...AND HANGS ON INTO FRIDAY WITH LINGERING SHOWERS OR ISO THUNDER OVER THE SOUTH. ALREADY INTO THE WEEKEND NOW SOME UNCERTAINTY REGARDING THE NEXT UPSTREAM WAVE APPROACHING FROM THE WEST FOR SATURDAY AND SUNDAY. GREAT LAKES HIGH NOW BEING MODELED TO STRENGTHEN OVER THE REGION AND IS NOW TRENDING TO KEEP AREA DRIER THAN PREVIOUSLY FORECAST. HAVE REDUCED POP CHANCES FOR BOTH DAYS... BUT HAVE NOT CUT OUT YET DUE TO CONFIDENCE CONCERNS AND CONSENSUS WITH NEIGHBORING OFFICES AT THIS POINT. IF TRENDS CONTINUE WITH TONIGHTS MODEL PACKAGES...THEN FURTHER REDUCTION IN RAIN CHANCES WILL BE WARRANTED. TEMPERATURES WILL REMAIN COOL THURSDAY WITH EXTENSIVE CLOUD COVER AND SHOWERS. BY FRIDAY SOME MODERATION IS EXPECTED WHICH SHOULD CONTINUE INTO THE WEEKEND. NORTHEAST FLOW WILL DEVELOP BY THURSDAY AFTERNOON AND CONTINUE THROUGH FRIDAY WITH SOME RISK FOR PATCHY FOG OVERNIGHT AS CLOUDS AND HIGH MOISTURE REMAINS IN THE BOUNDARY LAYER. LOOKING AHEAD TO NEXT WEEK....LESSENING CHANCES FOR RAIN WILL CONTINUE THROUGH THE PERIOD AS A RIDGE OF HIGH PRESSURE REMAINS IN THE AREA. SOME HINT AT RETURN MOISTURE BY NEXT WEDNESDAY AS A TROUGH DEVELOPS OVER THE HIGH PLAINS AND MOVES INTO THE CENTRAL PLAINS. && .AVIATION...07/06Z ISSUED AT 1139 PM CDT WED AUG 6 2014 SURFACE LOW OVER KANSAS THIS EVENING WILL SLOWLY MOVE EAST THROUGH MISSOURI ON THURSDAY. IOWA WILL REMAIN IN DEEP EASTERLY FLOW NORTH OF THE SYSTEM. MODEL SOUNDINGS SUGGEST THERE WILL BE PLENTY OF DEEP MOISTURE AVAILABLE. WILL FORECAST GENERALLY MVFR TO VFR CIGS THROUGH THE PERIOD. THERE WILL LIKELY BE SHOWERS...BUT KEPT THEM VICINITY AS OPPOSED TO PUTTING THEM DIRECTLY IN THE TAFS. && .HYDROLOGY... ISSUED AT 328 PM CDT WED AUG 6 2014 THREAT OF HEAVY RAINS WILL PERSIST THROUGH TODAY THURSDAY WITH AMPLE MOISTURE IN PLACE BEING TRANSPORTED INTO THE STATE. URBAN AREAS WOULD BE MOST LIKELY TO EXPERIENCE ANY FLOODING ISSUES AS MOST RURAL LOCATIONS HAVE DRY ANTECEDENT CONDITIONS. MINIMAL RISES ARE ANTICIPATED ON AREA RIVERS. && .DMX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 7 AM CDT THURSDAY FOR ADAIR-CLARKE- DECATUR-LUCAS-MADISON-RINGGOLD-UNION-WAYNE. && $$ UPDATE...JOHNSON SHORT TERM...ZOGG LONG TERM...REV AVIATION...JOHNSON HYDROLOGY...ZOGG
AREA FORECAST DISCUSSION
NWS GOODLAND KS
218 AM MDT THU AUG 7 2014 .UPDATE... ISSUED AT 1157 PM MDT WED AUG 6 2014 MESOSCALE INFLUENCES ACTING ON AN UNCAPPED AND UNSTABLE AIR MASS HAS ALLOWED THUNDERSTORMS TO INTENSIFY AND MOVE INTO THE NORTHEAST PORTION OF THE AREA. THE HRRR HAS CAUGHT ONTO THIS AND USED IT AS A BASIS FOR THE REST OF THE NIGHT. NOT SURE WHAT THIS COMPLEX WILL DO TO ONSET OF STRATUS AND FOG LATER IN THE NIGHT AND TOMORROW MORNING. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 1228 PM MDT WED AUG 6 2014 A FEW ISOLATED AFTERNOON/EVENING THUNDERSTORMS MAY POP UP AS CONVECTIVE TEMPERATURES ARE REACHED TODAY...BUT OVERALL RISING HEIGHTS AND DRY MID LEVELS EVIDENT ON WATER VAPOR WILL LIMIT COVERAGE. A BACK DOOR COLD FRONT WILL SLIP THROUGH THE AREA FROM NEBRASKA OVERNIGHT AND AS SURFACE WINDS VEER TO NORTHEAST AND UPSLOPE COMPONENT IS MAXIMIZED EXPECT TO SEE STRATUS AND/OR FOG DEVELOP LATE...LINGERING INTO MID THURSDAY MORNING. RIDGE AXIS WILL MOVE EAST ON THURSDAY AFTERNOON FOLLOWED BY A DISTURBANCE MOVING OUT OF NORTHERN COLORADO. THUNDERSTORM CHANCES WILL BE BEST IN EASTERN COLORADO THURSDAY AFTERNOON ASSOCIATED WITH THAT SYSTEM. TEMPERATURES TONIGHT AND THURSDAY WILL BE NEAR NORMAL WITH LOWS MAINLY IN THE 60S AND HIGHS AROUND 90. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 217 AM MDT THU AUG 7 2014 BROAD H5/H7 UPPER RIDGE IN PLACE OVER THE WESTERN PORTIONS OF THE COUNTRY...SHIFTING SLOWLY TOWARDS THE CENTRAL PLAINS BY MIDWEEK NEXT WEEK...THEN FLATTENING TO MORE ZONAL BY WEDNESDAY NIGHT INTO THURSDAY. MODELS DO SUPPORT A FEW SHORTWAVES WORKING OVER THE H7 RIDGE THRU THE FORECAST PERIOD...SUPPORTED BY LEE-SIDE TROUGH AT THE SURFACE. BASED ON MODEL MOVEMENT OF THIS TROUGH...PLACEMENT OF THE 700 MB SHORTWAVES WILL FOCUS MORE AREAL COVERAGE EARLY ON SUNDAY...TAPERING DOWN AS WEEK PROGRESSES DUE TO LEE-SIDE TROUGH BEGINNING TO WORK EAST OFF THE FRONT RANGE...AND INTO THE CENTRAL PLAINS WHERE BETTER DYNAMICS TO SUPPORT CONVECTION WILL OCCUR. THE TROUGH WILL BE THE DIVIDING LINE TO 60-65 DEWPOINTS TO OUR EAST AND 45-55 DEWPOINTS WEST. LOOKING FOR HIGH TEMPERATURES TO RANGE FROM THE MID 80S TO LOWER 90S. SLIGHTLY WARMER BIAS IN LATEST GFS VERSUS ECMWF SO WILL TAKE BLEND. MUGGY OVERNIGHT LOWS ON TAP FOR THE AREA AS A RESULT OF HIGH DEWPOINTS IN AREA WITH OVERNIGHT LOWS EXPECTED TO RANGE FROM THE LOW TO MID 60S OVER WESTERN ZONES...AND 65-70F FOR EASTERN ZONES. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1157 PM MDT WED AUG 6 2014 MODELS HAVE CAUGHT ON A LITTLE BETTER ON THE LIKELIHOOD OF STRATUS AND FOG BUT DISAGREE. THIS IS ALSO COMPLICATED BY AN INTENSE CLUSTER OF THUNDERSTORMS THAT WILL SOON AFFECT THE KMCK TAF. CONDITIONS WILL STAY VFR AT KMCK BUT WILL GET CLOSE TO MVFR. AFTER THE THUNDERSTORMS MOVE THROUGH IFR TO MVFR CONDITIONS WILL OCCUR AT KMCK UNTIL MID MORNING. FOG AND STRATUS WILL ALSO PRODUCE MVFR TO OCCASIONAL IFR CONDITIONS AT KGLD UNTIL MID MORNING. THUNDERSTORMS ARE EXPECTED TO DEVELOP LATER IN THE AFTERNOON WITH A LARGE COMPLEX OF THUNDERSTORMS TO AFFECT BOTH TAF SITES. SO FELT CONFIDENT ENOUGH TO ADD THUNDERSTORMS TO THE FORECAST DURING THAT TIME. KEPT CONDITIONS VFR AT THIS TIME BUT MUCH LOWER CONDITIONS WILL BE POSSIBLE DUE TO THE VERY MOIST AND UNSTABLE AIR MASS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...024 LONG TERM...JN AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1203 AM MDT THU AUG 7 2014 .UPDATE... ISSUED AT 1157 PM MDT WED AUG 6 2014 MESOSCALE INFLUENCES ACTING ON AN UNCAPPED AND UNSTABLE AIR MASS HAS ALLOWED THUNDERSTORMS TO INTENSIFY AND MOVE INTO THE NORTHEAST PORTION OF THE AREA. THE HRRR HAS CAUGHT ONTO THIS AND USED IT AS A BASIS FOR THE REST OF THE NIGHT. NOT SURE WHAT THIS COMPLEX WILL DO TO ONSET OF STRATUS AND FOG LATER IN THE NIGHT AND TOMORROW MORNING. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 1228 PM MDT WED AUG 6 2014 A FEW ISOLATED AFTERNOON/EVENING THUNDERSTORMS MAY POP UP AS CONVECTIVE TEMPERATURES ARE REACHED TODAY...BUT OVERALL RISING HEIGHTS AND DRY MID LEVELS EVIDENT ON WATER VAPOR WILL LIMIT COVERAGE. A BACK DOOR COLD FRONT WILL SLIP THROUGH THE AREA FROM NEBRASKA OVERNIGHT AND AS SURFACE WINDS VEER TO NORTHEAST AND UPSLOPE COMPONENT IS MAXIMIZED EXPECT TO SEE STRATUS AND/OR FOG DEVELOP LATE...LINGERING INTO MID THURSDAY MORNING. RIDGE AXIS WILL MOVE EAST ON THURSDAY AFTERNOON FOLLOWED BY A DISTURBANCE MOVING OUT OF NORTHERN COLORADO. THUNDERSTORM CHANCES WILL BE BEST IN EASTERN COLORADO THURSDAY AFTERNOON ASSOCIATED WITH THAT SYSTEM. TEMPERATURES TONIGHT AND THURSDAY WILL BE NEAR NORMAL WITH LOWS MAINLY IN THE 60S AND HIGHS AROUND 90. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 245 PM MDT WED AUG 6 2014 THURSDAY NIGHT-SATURDAY...STILL EXPECTING SHOWERS AND THUNDERSTORMS (POSSIBLY AS AN MCS) WITH HEAVY RAINFALL/POSSIBLE FLASH FLOODING AND SOME GUSTY WINDS TO MOVE EAST/SOUTHEAST ACROSS PARTS OF THE AREA THURSDAY NIGHT AS A WEATHER DISTURBANCE MOVES ACROSS THE AREA AHEAD OF AN APPROACHING UPPER TROUGH. MODELS MAINTAIN HIGHEST POPS GENERALLY ALONG/NORTH OF THE INTERSTATE WHERE UPPER DIVERGENCE STRONGEST. DRIER AIR MOVES IN FRIDAY MORNING BEFORE ANOTHER WEATHER DISTURBANCE REACHES FAR EASTERN COLORADO AND PERHAPS ADJACENT COUNTIES IN KANSAS BY 00Z SATURDAY. THIS SYSTEM MOVES ACROSS FRIDAY NIGHT WITH LITTLE FANFARE...POSSIBLY A FEW SHOWERS AND THUNDERSTORMS. ON SATURDAY SOME RESIDUAL MOISTURE RESIDES OVER THE AREA AND WITH AFTERNOON HEATING MAY SPARK A FEW SHOWERS AND THUNDERSTORMS DEPENDING ON YOUR MODEL PREFERENCE. FOR NOW HAVE IT DRY FOLLOWING THE GFS SOLUTION. LOW TEMPERATURES THURSDAY AND FRIDAY NIGHTS IN THE UPPER 50S TO LOW 60S IN EASTERN COLORADO WITH LOW TO MID 60S EAST OF THE STATE LINE. HIGHS FRIDAY IN THE LOW TO MID 80S WITH MID 80S TO AROUND 90 SATURDAY. SATURDAY NIGHT-WEDNESDAY... UPPER RIDGE BUILDS INTO THE AREA SATURDAY THROUGH MONDAY THEN STARTS TO SHIFT EASTWARD OVER THE AREA TUESDAY AS LOW PRESSURE MOVES INTO NEVADA/UTAH FROM THE SOUTHWEST. ON WEDNESDAY THE UPPER LOW OR ITS REMNANTS LIFT NORTHEAST PUSHING THE RIDGE AXIS EAST OF THE AREA. MOISTURE REMAINS PLENTIFUL FOR SHOWERS AND THUNDERSTORMS NEARLY EVERY DAY. THE BEST CHANCE APPEARS TO BE SUNDAY/SUNDAY NIGHT THEN AGAIN TUESDAY AFTERNOON THROUGH WEDNESDAY. LOWS IN THE 60S THROUGH MONDAY NIGHT WITH MID 60S TO AROUND 70 TUESDAY NIGHT. HIGHS IN THE MID 80S TO AROUND 90 SUNDAY AND MONDAY...AROUND 90 TUESDAY THEN MID/UPPER 80S IN EASTERN COLORADO WITH AROUND 90/LOW 90S EAST OF THE STATE LINE WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1157 PM MDT WED AUG 6 2014 MODELS HAVE CAUGHT ON A LITTLE BETTER ON THE LIKELIHOOD OF STRATUS AND FOG BUT DISAGREE. THIS IS ALSO COMPLICATED BY AN INTENSE CLUSTER OF THUNDERSTORMS THAT WILL SOON AFFECT THE KMCK TAF. CONDITIONS WILL STAY VFR AT KMCK BUT WILL GET CLOSE TO MVFR. AFTER THE THUNDERSTORMS MOVE THROUGH IFR TO MVFR CONDITIONS WILL OCCUR AT KMCK UNTIL MID MORNING. FOG AND STRATUS WILL ALSO PRODUCE MVFR TO OCCASIONAL IFR CONDITIONS AT KGLD UNTIL MID MORNING. THUNDERSTORMS ARE EXPECTED TO DEVELOP LATER IN THE AFTERNOON WITH A LARGE COMPLEX OF THUNDERSTORMS TO AFFECT BOTH TAF SITES. SO FELT CONFIDENT ENOUGH TO ADD THUNDERSTORMS TO THE FORECAST DURING THAT TIME. KEPT CONDITIONS VFR AT THIS TIME BUT MUCH LOWER CONDITIONS WILL BE POSSIBLE DUE TO THE VERY MOIST AND UNSTABLE AIR MASS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...024 LONG TERM...99 AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
352 AM EDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM EDT THU AUG 7 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG AXIS EXTENDING FM MN INTO NW ONTARIO...WITH SFC HI PRES ELONGATED FM JAMES BAY INTO FAR WRN LK SUP. VERY DRY/STABLE MID LVLS SHOWN ON THE LOCAL 00Z RAOBS AND THE LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE RDG HAVE RESULTED ARE BRINGING MOCLR SKIES TO THE CWA. WITH LGT WINDS UNDER THE MOCLR SKIES...SOME PATCHY FOG HAS FORMED. THERE IS A SHRTWV JUST E OF LK WINNIPEG THAT IS LIFTING SLOWLY NEWD...AND THERE ARE SOME BKN MID/HI CLDS OVER NW MN AND FAR NW ONTARIO. TEMPS/RH/FIRE WX PARAMETERS ARE THE MAIN FCST CONCERNS IN THE SHORT TERM AS UPR RDG/SFC HI PRES ARE FCST TO DOMINATE THRU TNGT. TODAY...SFC HI PRES IS FCST TO CENTER OVER THE E HALF OF LK SUP AS UPR RDG SHIFTS TO AN AXIS FM UPR MI TO JAMES BAY. EXCEPT FOR SOME SCT CU ALONG AND INLAND FM LK BREEZE BNDRYS THAT DVLP UNDER THE RATHER FLAT PRES GRADIENT AS WELL AS SOME PATCHY HI CLDS WELL TO THE S OF SHRTWV LIFTING NEWD THRU ONTARIO...THE DAY WL FEATURE PLENTY OF SUNSHINE. WITH H85 TEMPS FCST TO PEAK AT 13-14C OVER THE W THIS AFTN...SIMILAR TO YDAY...EXPECT MAX TEMPS RISING INTO THE 70S/LO 80S AWAY FM THE LK MODERATION...WHICH WL BE ENHANCED NEAR THE BAY OF GREEN BAY AND ALONG LK SUP E OF THE KEWEENAW IN THE E H925 FLOW. SFC DEWPTS SHOULD MIX OUT AS LO AS THE UPR 40S THIS AFTN...RESULTING IN MIN RH DOWN TO 30-35 PCT AWAY FM LK MODERATION. DESPITE RECENT DRYNESS AT MANY LOCATIONS...LIGHT WINDS WL MITIGATE THE FIRE WX THREAT. TNGT...WITH SFC HI PRES REMAINING OVER THE E HALF OF LK SUP...EXPECT DRY WX. ALTHOUGH MID LVL DRY AIR WL REMAIN IN PLACE...SOME HI CLDS MAY DRIFT THRU THE UPR LKS ON THE SRN FLANK OF SHRTWV LIFTING TOWARD JAMES BAY. TEMPS OVER THE INTERIOR SHOULD STILL BOTTOM OUT IN THE 40S...COOLEST OVER THE INTERIOR E CLOSER TO THE HI AND LIGHTER H925 WINDS. ADDED SOME PATCHY FOG OVER THE INTERIOR CENTRAL AND E...WHERE EXPECTED MIN TEMPS ARE LIKELY TO FALL AOB CROSS OVER DEWPTS THIS AFTN. A BIT STRONGER S WIND AT H925 WL LIMIT THE DIURNAL FALL OVER THE W. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 345 AM EDT THU AUG 7 2014 MAIN ISSUES DURING THE LONG TERM WILL BE CONTINUED DRY WEATHER THROUGH THE WEEKEND WITH THE NEXT CHANCE OF RAIN PUSHING IN AHEAD OF A COLD FRONT FOR THE FIRST PART OF THE WORKWEEK. FRIDAY THROUGH SATURDAY...BROAD SURFACE RIDGING ALONG WITH UPPER LEVEL 500MB RIDGING WILL REMAIN IN PLACE ACROSS MUCH OF THE UPPER GREAT LAKES REGION THROUGH AS WELL AS MUCH OF THE EASTERN CONUS THROUGH THIS TIME FRAME. DRY WEATHER WILL BE THE RULE UNDER THE RIDGE AS MOISTURE ADVECTION WILL BE LIMITED WITH VERY LOW DEEP LAYER 1000-500MB RH VALUES. THE SURFACE HIGH WILL SLOWLY SHIFT TO THE EAST DURING THE DAY SATURDAY. THIS WILL KEEP LIGHT WINDS IN THE FORECAST WITH THE STRONGEST GUSTS EXPECTED TO BE ALONG LAKE BREEZE BOUNDARIES DURING THE AFTERNOON HOURS. CONDITIONS ARE BECOMING VERY DRY ACROSS MUCH OF THE U.P. AS THERE HAS BEEN VERY MINIMAL PRECIPITATION OVER THE PAST COUPLE WEEKS. THIS HAS ALLOWED BOTH SOIL AND VEGETATION TO BECOME DRY. DECENT MIXING CONDITIONS ARE EXPECTED TO OCCUR EACH AFTERNOON THROUGH THIS TIME PERIOD...WHICH WILL LEAD TO INCREASED FIRE DANGER...FORTUNATELY...WINDS WILL CONTINUE TO BE FAIRLY LIGHT AS PREVIOUSLY MENTIONED. HAVE KEPT LOWER AFTERNOON DEWPOINTS IN PLACE AS DRIER AIR ALOFT MIXES DOWN TO THE SURFACE WITH AFTERNOON HEATING. TEMPERATURES WILL CONTINUE TO WARM THROUGH THIS PERIOD WITH 850MB TEMPS WARMING FROM NEAR 13C THURSDAY AFTERNOON TO AROUND 14C BY SATURDAY AFTERNOON AS THE HIGH CONTINUES THE SLOW TREK EASTWARD. SATURDAY NIGHT THROUGH THE REMAINING EXTENDED...THE NEXT UPPER LEVEL TROUGH AND DEVELOPING SURFACE LOW ARE PROGGED TO BE NEAR THE JUST NORTH OF LAKE WINNIPEG SATURDAY NIGHT WITH A COLD FRONT STRETCHING SOUTHWESTWARD ACROSS THE DAKOTAS AS SHOWN BY ANALYZING 850 THETA E ALONG WITH SURFACE WINDS. THIS WILL BE THE MAIN FOCUS FOR SHOWER AND THUNDERSTORM ACTIVITY. THE LOW WILL SHIFT EASTWARD TO NORTHERN QUEBEC BY MONDAY AFTERNOON AS THE FRONT DRAPES ACROSS THE UPPER GREAT LAKES REGION. RIGHT NOW THE BEST CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY WOULD BE LATE SUNDAY NIGHT OVER WESTERN UPPER MI AND DURING THE DAY MONDAY ACROSS MOST OF UPPER MI. DEEP LAYER FORCING SHOULD BE PLENTIFUL ALONG THE FRONT TO ALLOW PRECIPITATION TO DEVELOP ACROSS THE AREA AS SHOWN BY OVERLAYING QCONV ALONG WITH 1000-500MB RH. THIS WILL ALSO BE AROUND THE SAME TIME THAT THE UPPER LEVEL 500MB TROUGH AXIS SWINGS ACROSS THE AREA HELPING TO KEEP INSTABILITY HIGH ENOUGH FOR CONTINUED THUNDERSTORM CHANCES. MOISTURE WILL NOT BE OVERLY ABUNDANT THEREFORE WILL KEEP THE BEST CHANCE POPS RIGHT ALONG AND JUST AHEAD OF THE FRONT ALONG THE FAIRLY NARROW RIBBON OF MOISTURE. THE FRONT IS PROGGED TO BE EAST OF THE AREA BY TUESDAY...HOWEVER...UPPER LEVEL TROUGHING AND LINGERING MOISTURE NEARBY...WOULD EXPECT SHOWERS TO LINGER THROUGH AT LEAST TUESDAY MORNING. DRY HIGH PRESSURE WILL BUILD IN AT THE SURFACE TUESDAY NIGHT AND LINGER THROUGH WEDNESDAY AS UPPER LEVEL 500MB HEIGHT RISES BEGIN TO PUSH BACK INTO THE UPPER PENINSULA. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 121 AM EDT THU AUG 7 2014 VFR CONDITIONS AND WINDS LESS THAN 10KTS WILL DOMINATE THROUGH MOST OF THE PERIOD. THE MAIN CONCERN HOWEVER WILL BE THE DEVELOPMENT OF FOG EARLY THIS MORNING AT IWD AND SAW. WITH MAINLY GROUND FOG EXPECTED THAT MAY BE VARIABLE...CONFIDENCE IN LOWER VSBY REMAINS MODERATE TO LOW...SO WILL KEEP 3-5MI PREDOMINANT VIS AT A MINIMUM THROUGH 12Z THURSDAY. ANY FOG THAT DOES DEVELOP SHOULD MIX OUT BY OR SHORTLY AFTER 12Z THURSDAY. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 AM EDT THU AUG 7 2014 HI PRES WILL DOMINATE THE UPPER GREAT LAKES THROUGH THIS WEEKEND... WITH LIGHT WINDS BELOW 15 KTS AND WAVES GENERALLY LESS THAN 2 FT. AFTER THE HI FINALLY MOVES OFF TO THE E...A COLD FRONT WILL CROSS LAKE SUPERIOR ON MON. N WINDS MAY INCREASE UP TO 20 KTS FOLLOWING THIS FRONTAL PASSAGE AND IN ADVANCE OF THE NEXT HI PRES BUILDING OVER ONTARIO. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KEC AVIATION...JLB MARINE...KC
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
359 AM CDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CDT THU AUG 7 2014 THE MODELS SHOW MOISTURE POOLING ACROSS SWRN NEB EARLY THIS EVENING WITH PRECIPITABLE WATER INCREASING TO AROUND 1.5 INCHES. ITS A LIKELY POP SITUATION AS THE H500MB RIDGE FLATTENS AND A DISTURBANCE ACROSS SWRN WY MOVES EAST SOUTHEAST THROUGH SWRN NEB TONIGHT. THE FCST DELAYS POPS BY 3 HOURS GIVEN THE BIAS IN MODEL TIMING WHICH BRINGS THE BEST RAIN CHANCES THIS EVENING AND OVERNIGHT WHICH IS MORE IN LINE WITH THE QPF FORECAST. HPC CARRIES THE BEST QPF MORE SOUTH THRU SWRN NEB THEN WRN KANSAS BUT THE RAP AND NAM CORFIDI VECTORS FOR A FORWARD PROPAGATING MCS SHOW EASTWARD MOTION WHICH SUPPORTS THE BLENDED QPF FORECAST WE HAVE PREPARED. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 357 AM CDT THU AUG 7 2014 MODELS ARE IN BETTER AGREEMENT IN THE EXTENDED THAN PREVIOUS RUNS WITH THE OVERALL PATTERN. SOUTHERN UPPER LEVEL RIDGE ON FRIDAY WILL BUILD NORTHWEST ACROSS THE ROCKIES OVER THE WEEKEND AS A LOW MOVES ACROSS TOWARDS CENTRAL CAL AND A TROUGH DIGS ACROSS THE GREAT LAKES. MODELS STALL THE CLOSED LOW ACROSS WESTERN CAL WITH THE RIDGE CONTINUING TO BUILD TOWARDS MONTANA BY TUESDAY. THE WESTERN LOW THEN LIFTS NORTH AND BEGINS TO FLATTEN THE RIDGE. PERIODIC CHANCES FOR RAIN PERSIST THROUGH MUCH OF THE FORECAST. OVER THE WEEKEND SEVERAL DISTURBANCES WILL RIDE NORTH OF THE RIDGE. TIMING OF THE WAVES VARIES BETWEEN THE MODELS AND FORECAST WILL RETAIN LOW CHANCE POPS THROUGH THE WEEKEND. WHILE POPS ARE IN NEARLY EVERY PERIOD OVER THE WEEKEND...NOT EXPECTING IT TO BE A WASH OF A WEEKEND. DEVELOPMENT ACROSS THE FRONT RANGE WITH ACTIVITY SLIDING EAST/SOUTHEAST ACROSS THE CWA. THERE WILL ALSO BE SOME ISOLATED LATE DAY ACTIVITY DUE TO A WEAKENING CAP DUE TO PLENTIFUL BL MOISTURE. THE RICH BL MOISTURE WILL ALSO NEED TO BE MONITORED FOR LATE NIGHT/MORNING PATCHY FOG. TEMPS OVER THE WEEKEND WILL BE SEASONALLY COOL /LOWER TO MID 80S/ DURING THE DAY AND MILD OVERNIGHT /LOWER TO MID 60S. AS WE START THE WORK WEEK...FLOW BECOMES M0RE NORTHWESTERLY. MODELS CONTINUE A TRAIN OF SHORT WAVES AROUND THE RIDGE...HOWEVER THEY BECOME SPACED OUT MORE. STILL GOING TO SEE OCCASIONAL POPS WITH EACH WAVE...AND TIMING IS HIGHLY UNCERTAIN THIS FAR OUT. WITH THE RIDGE BUILDING TO THE WEST...TEMPS SHOULD CLIMB A LITTLE. GUIDANCE IS IN THE MID AND UPPER 80S...WHICH IS CLOSER TO SEASONAL NORMS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1221 AM CDT THU AUG 7 2014 THE LINE OF THUNDERSTORMS IN SOUTHWEST NEBRASKA WILL AFFECT THE IML AREA UNTIL ABOUT 07Z. AFTER THAT...THUNDERSTORMS ARE NOT EXPECTED UNTIL 21Z WHEN THEY DEVELOP IN SOUTHWEST NEBRASKA (NEAR OGA AND IML). LATER TONIGHT...WIDESPREAD STRATUS WILL BRING LOW CEILINGS TO MUCH OF CENTRAL AND NORTHERN NEBRASKA. IN THE NORTH...OUR CONFIDENCE IS HIGH THAT THE CEILINGS WILL BE BELOW 1000 FEET AGL WITH PATCHY BR/FG RESTRICTING VISIBILITY TO LESS THAN 3SM. THAT WOULD INCLUDE VTN...ANW...ONL AND BBW. FARTHER SOUTH AND WEST...THAT IS...MHN... TIF...LBF AND OGA...THERE IS MORE UNCERTAINTY REGARDING THE CEILING BUT OUR CONFIDENCE IS FAIRLY HIGH THAT PATCHY BR/FG WILL DEVELOP. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
148 AM EDT THU AUG 7 2014 .SYNOPSIS... A COLD FRONT WILL SLIDE SOUTHEAST ACROSS THE REGION OVERNIGHT...REACHING THE CAROLINAS ON THURSDAY. HIGH PRESSURE SHOULD BUILD NORTH OF THE AREA THURSDAY INTO THURSDAY NIGHT BEFORE SLIDING OFF THE MID ATLANTIC COAST FRIDAY. A SERIES OF LOW PRESSURE SYSTEMS WILL MOVE ALONG THE BOUNDARY TO THE SOUTH FRIDAY NIGHT THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TODAY/... AS OF 845 PM EDT WEDNESDAY... WIDELY SCATTERED CONVECTION CONTINUES TO REDEVELOP ALONG RESIDUAL OUTFLOW THIS EVENING GIVEN LEFTOVER WEAK INSTABILITY PER SPC MESO ANALYSIS AND STEEP LAPSES ABOVE THE SURFACE OFF EVENING SOUNDINGS. HOWEVER CAP ALOFT AND DEEP WEST/NW FLOW HELPING TO KEEP THE LID ON WIDESPREAD DEEP CONVECTION SO STILL EXPECTING MOST SHRA TO FADE WITH LOSS OF HEATING. THIS IN LINE WITH THE LATEST SHORT TERM HRRR AND RAP WHICH SHOWS LITTLE COVERAGE SHORTLY AFTER SUNSET SO KEEPING POPS SIMILAR OVERNIGHT WITH FEW REMAINING SHRA BEFORE MIDNIGHT. OTRW WEAK FRONT NOW STILL NW OF THE MOUNTAINS TO DRIFT THROUGH LATE BEFORE DIPPING SOUTH OF THE AREA BY MORNING. CANT TOTALLY RULE OUT ISOLATED SHRA WITH THE BOUNDARY BUT GIVEN LACK OF SUPPORT THINK MAINLY PC OVERALL. LOW FOG STABILITY VALUES SUPPORT AT LEAST PATCHY FOG VALLEYS AND WHERE HEAVIER DOWNPOURS HAVE OCCURRED THIS EVENING SO BEEFING UP COVERAGE IN SPOTS. BUMPED UP LOWS A BIT GIVEN LINGERING MOIST DEWPOINTS/CLOUDS AND LAGGING COOL ADVECTION WELL TO THE NW BUT OVERALL MOSTLY 60S FOR LOWS. PREVIOUS VALID DISCUSSION... A COLD FRONT WAS MAKING ITS WAY INTO THE WESTERN PART OF THE FORECAST AREA. THE FRONT IS EXPECTED TO CROSS THE AREA TONIGHT AND BE SOUTH OF THE REGION BY THURSDAY MORNING. ISOLATED TO SCATTERED SHOWERS AND STORMS ARE EXPECTED THE REMAINDER OF THIS AFTERNOON INTO THE EVENING HOURS ALONG IN ADVANCE OF THE FRONT. HRRR AND RNK WRK- ARW MODELS HAVE BEEN DOING DO A GOOD JOB THE PAST FEW DAYS WITH TIMING AND LOCATION OF LATE AFTERNOON AND EARLY EVENING ACTIVITY. WILL CONTINUE PLACE STRONG WEIGHT ON THEIR SOLUTIONS FOR WHERE THE FOCUS OF THE BEST COVERAGE WILL BE. THAT REGION WILL PRIMARILY BE AREAS NEAR AND NORTHWEST TO NORTHEAST OF LYNCHBURG AND ALSO ACROSS THE NORTHERN MOUNTAINS OF NC AND PARTS OF THE MOUNTAIN EMPIRE AND NEW RIVER VALLEY REGION OF SOUTHWEST VIRGINIA. PRECIPITATION IS EXPECTED TO COMPLETELY DISSIPATE BETWEEN MIDNIGHT AND 200 AM TONIGHT. THE NOTABLY DRIER AIR BEHIND THE FRONT IS NOT EXPECT TO ARRIVE UNTIL THURSDAY AFTERNOON. THIS WILL ALLOW FOR ONE MORE NIGHT OF SOME PATCHY MOUNTAIN AND RIVER VALLEY FOG...ESPECIALLY IN AREAS THAT RECEIVE PRECIPITATION THIS AFTERNOON AND EVENING. HIGH LEVEL CLOUDS ARE EXPECTED OVERNIGHT FOR MUCH OF THE REGION. LOWER...MORE NUMEROUS CLOUDS ARE POSSIBLE NEAR A BLUEFIELD TO LEWISBURG WV LINE WHERE AN UPSLOPE FLOW WITHIN A SHALLOW MOIST LAYER WILL HELP RE- ESTABLISH LOW LEVEL CLOUDS AT AND BELOW THE INVERSION LEVEL. ON THURSDAY...HIGH PRESSURE WILL BUILD INTO OH/PA WITH THE SOUTHERN EXTENT OF ITS AXIS NOSING INTO THE FORECAST AREA. WITH IT WILL COME DRIER AND COOLER WEATHER. WHILE NOT FORECAST...WE MAY HAVE TO WATCH FOR SOME LATE DAY ISOLATED SHOWERS IN THE FAR SOUTHERN PART OF THE AREA WHERE DAYTIME HEATING WILL BE MAXIMIZED COINCIDENT TO WHERE THE BEST REMAINING LOW LEVEL MOISTURE WILL BE LOCATED. AT THIS TIME...CONFIDENCE IS TOO LOW TO INCLUDE THE ISOLATED SHOWERS IN THE FORECAST. HIGH TEMPERATURES WILL RANGE FROM AROUND 80 TO THE LOWER 80S ACROSS THE MOUNTAINS WITH LOW TO MID 80S ACROSS THE PIEDMONT. && .SHORT TERM /TONIGHT THROUGH SATURDAY NIGHT/... AS OF 400 PM EDT WEDNESDAY... THE FORECAST GOING INTO THE WEEKEND SHOULD LOOK FAMILIAR TO WHAT WAS EXPERIENCED THE END OF LAST WEEK WITH TRANSITION BACK TO MUCH COOLER THAN NORMAL TEMPERATURES. THE UPPER LEVEL PATTERN REMAINS PRETTY MUCH UNCHANGED...FAVORING A RIDGE OF HIGH PRESSURE OVER THE PLAINS AND ROCKIES...AND TROUGHINESS OVER THE EASTERN CONUS...THE DEGREE OF AMPLIFICATION THE ONLY THING THAT HAS BEEN CHANGING WITH TIME. TO START THE DAY FRIDAY...THE UPPER LEVEL TROUGH WILL SLIDE OFF THE EAST COAST WITH SURFACE HIGH PRESSURE WEDGING DOWN THE EAST SIDE OF THE APPALACHIANS. THIS WILL SET STAGE FOR A MULTIDAY PERIOD OF EASTERLY WINDS OFF THE ATLANTIC OCEAN...A PATTERN THAT GENERALLY FEATURES COOL TEMPERATURES AND ABUNDANT LOW LEVEL CLOUD COVER FOR MUCH OF OUR FORECAST AREA. TO GO ALONG WITH THE COOL CLOUD COVER THERE WILL BE SHOWERS. A SURFACE FRONT WILL BE NEARLY STATIONARY...JUST SOUTH OF OUR FORECAST AREA...EXTENDING FROM SOUTH CAROLINAS WESTWARD INTO THE MID MS VALLEY. THIS FRONT WILL BECOME THE FOCUS FOR SHOWERS AND THUNDERSTORMS...THE STRONGEST STORMS PRIMARILY SOUTH AND WEST OF OUR FORECAST AREA. WEDGE OF STABLE AIR ON THE EAST SIDE OF THE MTNS WILL PROHIBIT MUCH IN THE WAY OF STORMINESS HERE...HOWEVER COMBINATION OF ISENTROPIC LIFT...AND THE EASTERLY UPSLOPE WIND FLOW WILL PROVIDE LIFT FOR PERIODIC SHOWERS ACROSS OUR FCST AREA BEGINNING FRIDAY AND CONTINUING THROUGH THE WEEKEND. IN GENERAL...QPF IS EXPECTED TO BE LESS THAN AN INCH...WITH THE EXCEPTION OF AREAS WEST OF I77 WHERE MORE SUN AND INSTABILITY WILL EXIST...AND FARTHER SOUTH INTO NORTH CAROLINA CLOSER TO INFLUENCE OF THE SURFACE FRONT. BOTH THE GFS AND ECMWF DEVELOP CONVECTION ALONG AND NORTH OF THE FRONTAL BOUNDARY FROM THE LOWER MISSOURI VALLEY EAST TOWARD THE OHIO VALLEY LATE THURSDAY NIGHT...THEN RIDE THE CONVECTION SOUTHEAST INTO THE MOUNTAINS BY MIDDAY FRIDAY. RAIN SPREADS EAST FRIDAY AFTERNOON INTO FRIDAY NIGHT. THESE SAME MODELS ARE ALSO ADVERTISING HIGH CHC THREAT FOR PRECIP RIGHT ON THROUGH THE WEEKEND. WITH ABUNDANT CLOUD COVER...PRECIPITATION...AND AN EASTERLY WIND... WENT WELL BELOW CLIMO. HIGHS THIS WEEKEND WILL LIKELY BE 8 TO 15 DEGREES BELOW NORMAL. FOR SATURDAY WE WILL BE LUCKY TO TOUCH 70. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 410 PM EDT WEDNESDAY... COOL PATTERN LOOKS LIKE IT WILL LINGER THROUGH MONDAY BEFORE WARMING BACK UP THE MIDDLE OF NEXT WEEK. OVERALL THIS PERIOD WILL BE CHARACTERIZED BY THE SAME NEARLY STATIONARY...WAVY FRONT POSITIONED JUST SOUTH OF THE FORECAST AREA. SFC HIGH WILL BE OVER THE MID ATLANTIC/NORTHEAST WEDGING SW...BUT THIS AIRMASS IS EXPECTED TO MODIFY WITH TIME...RESULTING IN A UPWARD TEMPERATURE TREND TUESDAY AND WEDNESDAY. MAINTAINED DAILY THREAT FOR SHOWERS THROUGH THE PERIOD. INTRODUCED THUNDER BACK IN THE FORECAST FOR MID WEEK...THE RETURN OF SOME SUN PROVIDING INSTABILITY TO FEED DEEPER CONVECTION. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 140 AM EDT THURSDAY... EXPECT PATCHY MVFR FOG IN THE MOUNTAIN AND RIVER VALLEYS EARLY THIS MORNING AND IN LOCATIONS THAT HAD RAIN WEDNESDAY AFTERNOON AND EVENING. LOW CONFIDENCE AS TO HOW EXTENSIVE THE FOG WILL BE SINCE HIGH CLOUDS COVERED MUCH OF THE AREA AD SINCE DEW POINTS WILL BE DROPPING LATE TONIGHT. MOST LIKELY LOCATIONS FOR IFR OR LOWER VISIBILITIES WILL BE AT KLWB AND KLYH. THE SUB-VFR CONDITIONS WILL QUICKLY IMPROVE TO VFR AROUND 13Z/9AM. DRY WEATHER IS EXPECTED. THERE WILL BE ENOUGH MIXING DURING THE DAY TO LOWER DEW POINTS. THIS WILL LIMIT FOG FORMATION TONIGHT. EXTENDED AVIATION DISCUSSION... LENGTHY PERIOD OF SUB-VFR CONDITIONS POSSIBLE FRIDAY NIGHT AND SATURDAY AS THE FRONT BUCKLES NORTH AGAIN WITH THE APPROACH AND PASSAGE OF AN AREA OF LOW PRESSURE. GOOD POTENTIAL FOR PLENTY OF RAIN...LOW CLOUDS AND REDUCED VISIBILITIES. SUNDAY INTO MONDAY...COLD AIR DAMMING WEDGE IN PLACE ACROSS THE EAST WITH POTENTIAL FOR CONTINUATION OF SUB-VFR CATEGORY CONDITIONS. MODELS VARY ON THE EXTENT THAT ANOTHER UPPER LOW WILL SPREAD ADDITIONAL PRECIPITATION INTO AT LEAST THE WESTERN PARTS OF THE AREA BY MONDAY. THUNDERSTORMS ARE POSSIBLE OUTSIDE THE INFLUENCE OF THE WEDGE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...AMS/JH NEAR TERM...DS/JH SHORT TERM...PM LONG TERM...PM AVIATION...AMS/PH
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
256 AM CDT THU AUG 7 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 256 AM CDT THU AUG 7 2014 WATER VAPOR IMAGERY COMBINED WITH 500MB ANALYSIS SHOWS A MID-LEVEL SHORTWAVE TROUGH ENTERING WESTERN IA/EASTERN KS. CONVECTION ASSOCIATED WITH THIS WAVE HAS BEEN TAPERING OFF ON THE NORTH END AWAY FROM OUR AREA AND WAS NOW CONFINED MAINLY ALONG/S OF I-80 IN IA. MEANWHILE...SURFACE HIGH PRESSURE WAS SPRAWLED OUT ACROSS SOUTHERN ONTARIO/LAKE SUPERIOR THROUGH NORTHERN WI AND MN. BESIDE A BAND OF CIRRUS ACROSS PORTIONS OF NORTHEAST IA INTO FAR SOUTHWEST WI...DRY AIR OUTFLOW FROM THE HIGH WAS PRODUCING MOSTLY CLEAR SKIES ACROSS THE ARX FORECAST AREA. ISOLATED POCKETS OF FOG WERE NOTED ACROSS CENTRAL WI AND THE WI RIVER VALLEY. ARX WEBCAM SHOWING SOME STRATUS OVER THE MISSISSIPPI CHANNEL AND THINKING THIS WILL GET A LITTLE MORE EXTENSIVE THROUGH THE EARLY MORNING HOURS GIVEN LIGHT WINDS AND MOSTLY CLEAR SKIES. OTHERWISE...TEMPERATURES ACROSS THE AREA EARLY THIS MORNING WERE IN THE MIDDLE 50S TO THE LOWER 60S. FOR TODAY...HIGH PRESSURE WILL KEEP MOST OF THE AREA DRY TODAY. WILL BE WATCHING THAT MID-LEVEL WAVE ACROSS WESTERN IA TRACK EAST...WHICH MAY SPREAD ISOLATED SHOWERS/OUTSIDE CHANCE OF A THUNDERSTORM INTO PORTIONS OF NORTHEAST IA LATER THIS MORNING INTO THE AFTERNOON HOURS. FORCING IS RATHER WEAK WITH THIS WAVE AND GIVEN DRIER EASTERLY SURFACE FLOW...KEPT RAIN CHANCE VERY LOW...MAXED OUT IN THE 20-25 PERCENT RANGE. SKIES WILL BE MOSTLY SUNNY ALONG AND NORTH OF I-94 WITH MORE MID/HIGH CLOUD COVER ACROSS NORTHEAST IA/SOUTHEAST MN/SOUTHWEST WI. OTHERWISE...ANOTHER SEASONABLY WARM DAY ON TAP WITH HIGHS EXPECTED TO TOP OFF IN THE MIDDLE 70S TO THE LOWER 80S. A FEW SHOWERS ARE STILL POSSIBLE BEFORE MIDNIGHT ACROSS PORTIONS OF NORTHEAST IA/FAR SOUTHWEST WI AS THE MID-LEVEL TROUGH MAKES ITS WAY EAST INTO IL. WAS THINKING SOME FOG AFTER MIDNIGHT...BUT WITH A BIT TIGHTER PRESSURE GRADIENT TONIGHT AROUND THE HIGH ACROSS THE GREAT LAKES...THINKING WINDS WILL KEEP THINGS CLEAN. THEY MAY BE SOME PATCHY RIVER VALLEY FOG IN THE WISCONSIN/MISSISSIPPI RIVER VALLEYS BUT NOT CONFIDENT ENOUGH TO INCLUDE IN THE WEATHER GRIDS AT THIS POINT. PLAN ON LOW TEMPERATURES TONIGHT IN THE 55-60 DEGREE RANGE. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 256 AM CDT THU AUG 7 2014 MODEL CONSENSUS SHOWS HIGH PRESSURE OVER THE GREAT LAKES KEEPING THE AREA DRY ON FRIDAY WITH HIGHS TOPPING OFF IN THE UPPER 70S TO THE LOWER 80S. DRY WEATHER WILL CONTINUE RIGHT THROUGH SUNDAY NIGHT AS HIGH PRESSURE REMAINS THE DOMINANT WEATHER FEATURE. PLAN ON HIGHS SAT AND SUN A FEW DEGREES EITHER SIDE OF 80...COOLING INTO THE MIDDLE 50S TO THE LOWER 60S AT NIGHT. NEXT CHANCE OF SHOWERS AND THUNDERSTORMS WILL BE MONDAY INTO TUESDAY AS BOTH THE ECMWF AND GFS HAVE AN UPPER LEVEL TROUGH AND SURFACE COLD FRONT MOVING SLOWLY SOUTHEAST THROUGH THE REGION. SURFACE CONVERGENCE TO TRIGGER CONVECTION LOOKS PRETTY WEAK AT THIS POINT WITH MAIN UPPER LEVEL FORCING REMAINING FARTHER NORTH IN CANADA. AS SUCH...KEEPING POPS FAIRLY LOW IN THE 20-30 PERCENT RANGE. OTHERWISE...HIGHS LOOKS LIKE HIGHS ON MONDAY SHOULD TOP OFF AROUND 80 ON MONDAY AND THEN COOLING A COUPLE DEGREES COOLER ON TUESDAY. STRONG RIDGE OF HIGH PRESSURE RETURNS TO THE REGION ON WEDNESDAY FOR DRY AND WARM CONDITIONS AS HIGHS TOP OFF IN THE UPPER 70S TO THE MIDDLE 80S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1100 PM CDT WED AUG 6 2014 FORECAST CONCERNS CONTINUE TO FOCUS ON A FOG THREAT...SPECIFICALLY IN THE RIVER VALLEYS...WITH A GREATER IMPACT AT KLSE AS A RESULT. SHOWERS AND STORMS PERSIST ACROSS SOUTHERN IA AND MO LATE THIS EVENING...SENDING SOME HIGH CIRRUS THIS WAY. IT APPEARS TO BE THIN IN NATURE THOUGH...AND ITS IMPACT ON DIURNAL COOLING COULD BE NEGLIGIBLE. SFC WINDS ARE GENERALLY LIGHT EAST TO CALM...WITH BUFKIT SOUNDINGS POINTING TO THIS LIGHT WIND LAYER EXTENDING UPWARDS OF 4K FT. PREVIOUS RAP AND NAM INCREASE WINDS JUST OFF THE SFC BEFORE 12Z...AND THIS SUGGESTION IS STILL THERE IN LATEST MODEL RUNS...BUT MORESO TOWARD 12Z RATHER THAN EARLIER. WITH AN INVERSION ALREADY IN PLACE...THIS LATE INCREASE IN WIND SHOULD HAVE MINIMAL IMPACT AT THE SFC. KLSE T/TD SPREAD WAS 7 DEGREES AT 03Z...RIGHT ON THE EDGE OF WHAT LOCAL STUDIES FAVOR FOR 1/4SM FORMATION. HOWEVER...COUPLE THIS WITH THE LIGHT WIND PROFILE AND CONDITIONS ARE LOOKING MORE FAVORABLE FOR FOG IN THE RIVER VALLEYS...AND AT LEAST SUB 1SM AT KLSE. ANY FOG THAT DEVELOPS SHOULD LIFT BY 14Z. FOR KRST...SIMILAR T/TD SPREAD AND LIGHT WIND FIELD. EXPECT SOME MVFR VSBYS FOR A PERIOD OVERNIGHT INTO THE EARLY MORNING HOURS. CONDITIONS AT BOTH SITES SHOULD THEN BE VFR INTO THURSDAY NIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1042 PM MDT WED AUG 6 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 320 PM MDT WED AUG 6 2014 CONVECTION WAS EARLY TO START TODAY WITH INITIATION OCCURRING AS A RESULT OF TWO SEPARATE CATALYSTS. THE FIRST AREA OF CONVECTION DEVELOPED OVR THE HIER ELEVATIONS OF CARBON/ALBANY/LARAMIE COUNTIES WHERE LFQ OF A 75 KNOT H3 JET STREAK APPROACHES. THE OTHER AREA OF CONVECTION FIRED IN CLOSE PROXIMITY OF A WELL-DEFINED SHORTWAVE THAT WAS DROPPING SOUTHEAST FROM NE WY INTO THE NRN NEBRASKA PANHANDLE. AT THE SFC...60F ISODROSOTHERM EXTENDS ALONG THE NORTH PLATTE RIVER VALLEY WITH A WEAK NW/SE FRONTAL BOUNDARY EXTENDING ALONG THE ERN PLAINS. CONVECTIVE COVERAGE AND STRENGTH WILL INCREASE AND EXPAND AS THE H3 JET STREAK LIFTS NORTHEAST AND INTERACTS WITH THE SHORTWAVE ENERGY...MOISTURE AND SFC BOUNDARY. SPC ANALYSIS DEPICTS ABOUT 1500 J/KG OF AVAILABLE SBCAPES EXTENDING FROM ERN WYOMING INTO THE WRN NEBRASKA PANHANDLE. BEST COVERAGE AND ORGANIZATION WILL LIKELY BE EAST OF THE SFC BOUNDARY AS THE SHEAR ENVIRONMENT BECOMES MORE FAVORABLE LATE THIS AFTERNOON AND EARLY THIS EVENING. A FEW STORMS MAY BECOME STRONG TO LOCALLY SEVERE IN THIS AREA TONIGHT. CONVECTION WILL DISSIPATE AS THE AIR MASS STABILIZES LATE THIS EVENING. RIDGE AXIS FLATTENS FARTHER TO THE SOUTH ON THURSDAY AS A DEEPER SHORTWAVE MOVES INTO WRN WYOMING. OTHERWISE...SEE LITTLE CHANGE IN THE OVERALL SYNOPTIC PATTERN. PWAT VALUES LOOK VERY SIMILAR TO THOSE TODAY WITH THE ONE INCH LINE HOVERING VERY CLOSE TO THE WY/NE STATELINE. LIKEWISE...MODELS CONTINUE TO PROG THE WK QUASISTATIONARY BOUNDARY DRAPED OVER THE ERN PLAINS. CONVECTION WILL DEVELOP IN SIMILAR TIMING AS TODAY WITH STRENGTHENING LATER IN THE AFTERNOON AND EARLY EVENING AS THEY ENCOUNTER A BETTER AIR MASS. SBCAPES ARE AGAIN PROGD TO REACH 1000-1500 J/KG. SO ALTHOUGH HEAVY RAIN WILL BE THE MAIN HAZARD TO ACCOMPANY THESE THUNDERSTORMS...A FEW MAY BECOME STRONG TO LOCALLY SEVERE. CONTINUED SHOWER/THUNDERSTORM CHANCES THURSDAY NIGHT AS THE AFOREMENTIONED SHORTWAVE MEANDERS TOWARDS THE CWFA. THIS SHORTWAVE WILL MOVE THROUGH AT SOME POINT ON FRIDAY. MODELS DIFFER SOME ON HOW THIS WILL EVOLVE. HOWEVER...IN ALL CASE EXPECT ANOTHER GOOD CHANCE FOR ADDL SHOWER AND THUNDERSTORM CHANCES DURING THE DAY ON FRIDAY. TEMPERATURES WILL VARY LITTLE THROUGH THE END OF THE WEEK WITH HIGHS CLIMBING INTO THE 80S EAST OF THE LARAMIE RANGE...WITH 70S/LOW 80S WEST. .LONG TERM...(SATURDAY THROUGH TUESDAY) ISSUED AT 320 PM MDT WED AUG 6 2014 AREA REMAINS IN A RATHER MOIST MONSOONAL PATTERN THROUGH MUCH OF THE EXTENDED WITH DIURNAL CHANCES OF STORMS. THE SUBTROPICAL HIGH IS LOCATED ACROSS THE SOUTHERN PLAINS FROM SAT THROUGH MON WHICH KEEPS MIDLEVEL FLOW SOUTH-TO-SOUTHWEST...WITH MOISTURE STREAMING IN FROM ARIZONA/UTAH. THE MOST WIDESPREAD COVERAGE OF STORMS LOOKS TO BE ON SUN AS SFC WINDS TURN EASTERLY IN RESPONSE TO A SFC HIGH OVER THE NORTHERN PLAINS. STEERING FLOW IS ALSO SOUTHERLY ON SUN AFTN SO MAY TO WATCH FOR HEAVY RAIN POTENTIAL ALONG THE LARAMIE RANGE FOOTHILLS. LI VALUES ARE -4C TO -6C ON SUN AND MON AFTNS...HOWEVER WITH BULK SHEAR AT 25 KTS...THE SVR POTENTIAL LOOKS LIMITED (WHICH IS NORMAL FOR MID AUG). TEMPS THROUGH EARLY NEXT WEEK WILL BE SEASONAL. THE GFS AND ECMWF BOTH INDICATE A SHORTWAVE PASSING OVER THE CWA ON TUES NIGHT WITH DRIER WEST TO NORTHWEST FLOW ALOFT BEHIND IT. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING) ISSUED AT 1038 PM MDT WED AUG 6 2014 CONVECTION HAS NEARLY COME TO AN END ACROSS SOUTHEAST WYOMING AND THE NEBRASKA PANHANDLE. REMNANT CELLS CONTINUE NEAR THE WYOMING/COLORADO STATE LINE. MOST OF THE PANHANDLE HAS SEEN MEASURABLE RAINFALL THIS PAST EVENING AND WITH SKIES CLEARING OUT...CONFIDENCE IS GROWING THAT WE WILL SEE LOW CLOUDS AND POSSIBLY FOG DEVELOPING. HRRR SHOWS THIS REALLY WELL AND FOLLOWED ITS GUIDANCE. KCDR AND KAIA SHOULD FALL TO IFR/VLIFR AFTER 09Z OR SHORTLY THERE AFTER. CONVECTION RETURNS THURSDAY AFTERNOON AND COULD PERSIST WELL INTO THE EVENING HOURS. && .FIRE WEATHER... ISSUED AT 320 PM MDT WED AUG 6 2014 THE UNSETTLED PATTERN WILL KEEP FIRE WEATHER CONCERNS AT BAY AT LEAST INTO THE UPCOMING WEEKEND. THE MONSOONAL MOISTURE FETCH WILL REMAIN IN PLACE...SPARKING DAILY AFTERNOON AND EARLY EVENING SHOWERS AND THUNDERSTORMS. THESE WILL BE EFFICIENT RAIN PRODUCERS SO EXPECT TO SEE A GOOD CHANCE OF WETTING RAINS FOR MOST LOCATIONS ACROSS THE DISTRICT. TEMPERATURES WILL BE SEASONAL...HOVERING IN THE UPPER 70S AND 80S ACROSS LOWER ELEVATIONS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...HAHN LONG TERM...FINCH AVIATION...CLAYCOMB FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS MIAMI FL
917 AM EDT THU AUG 7 2014 .UPDATE... CHANGES TO THE CURRENT FORECAST LOOK MINIMAL AT THIS TIME BASED ON CURRENT TRENDS AND OBSERVATIONS. THE 12Z MFL SOUNDING CAME IN WITH PWAT JUST ABOVE TWO INCHES WITH A VERY UNSTABLE ENVIRONMENT. THE MID LEVEL LAPSE RATE INCREASED SUBSTANTIALLY FROM YESTERDAY AND IS NOW 6.5 C/KM WITH A 500 MB TEMPERATURE OF -7C WHICH IS 1 DEGREE COOLER THAN ON WEDNESDAY. THE GRADIENT FLOW IS ALSO VERY WEAK SO STEERING FLOW WILL BE MUCH LESS THAN 5 MPH. GIVEN ALL OF THIS, LARGE OUTBREAK OF CONVECTION ALONG SEA BREEZE BOUNDARIES THAT SET UP SEEM NEARLY CERTAIN WITH VERY SLOW MOVING STORMS. THE CURRENT FORECAST SHOWS THE HIGHEST POPS CENTERED OVER THE INTERIOR BUT THE LATEST HRRR IS SHOWING MOST ACTION DEVELOPING ALONG THE EAST COAST SEA BREEZE AND MOVING ONLY VERY SLOWLY INLAND. SO MAY HAVE TO ADJUST HIGHER POPS FARTHER TO THE EAST BUT WITH SUCH SLOW FORECAST MOTION, WILL WAIT UNTIL DEVELOPMENT BEGINS TO OCCUR AND MAKE AN ASSESSMENT AT THAT TIME. KOB && .PREV DISCUSSION... /ISSUED 804 AM EDT THU AUG 7 2014/ AVIATION... MAINLY VFR CONDITIONS EXPECTED TO PREVAIL ACROSS ALL SOUTH FLORIDA TERMINALS THROUGH THE MORNING HOURS. CURRENTLY THE WINDS ACROSS THE REGION ARE LIGHT AND SOMEWHAT VARIABLE. AROUND THE 16-18Z TIME FRAME BOTH THE WEST AND EAST COAST SEA BREEZES EXPECTED TO FORM. SHOWERS/THUNDERSTORMS EXPECTED TO START AROUND 16Z-18Z WITH ALL TERMINALS ASSIGNED VCTS IN THAT TIME RANGE. STORM MOTION WILL BE SLOW AND SHOWERS/THUNDERSTORMS COULD FORM ALONG THE COASTAL ZONE WITH ALL TERMINALS POSSIBLY EXPERIENCING VERY BRIEF IFR CONDITIONS WITH SHOWERS/THUNDERSTORMS. 60 PREV DISCUSSION... /ISSUED 322 AM EDT THU AUG 7 2014/ DISCUSSION... EARLY WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW NORTH OF MAINE...WITH THE UPPER TROUGH AXIS EXTENDING SOUTHWARD ACROSS THE COAST OF THE MID ATLANTIC AND INTO THE SOUTHEAST STATES. WEAK HIGH PRESSURE STRETCHED ACROSS SOUTH FLORIDA AND THE WESTERN ATLANTIC. A WEAK UPPER LEVEL DISTURBANCE OVER NORTHERN FLORIDA WILL DROP SLOWLY SOUTHWARD TOWARDS CENTRAL FLORIDA AND THE LAKE REGION THROUGH THE DAY. AT THE SURFACE...THE RIDGE IS SLIGHTLY WEAKER...BUT THE FLOW ABOVE SURFACE WILL BE LIGHT OUT OF THE WEST. THIS WILL ALLOW THE GULF COAST SEA BREEZE TO PUSH IN QUICKLY...WITH SHOWERS AND STORMS DEVELOPING ACROSS THE WEST EARLIER IN THE DAY...WITH OUTFLOW BOUNDARIES ALLOWING STORMS TO DEVELOP ALONG IN THE INTERIOR...AND THEN TOWARDS THE EAST COAST AS OUTFLOW BOUNDARIES INTERACT WITH THE SEA BREEZE. WITH THE WEAK UPPER DISTURBANCE...A MORE ACTIVE DAY OVERALL IS EXPECTED. A WEAK TROPICAL WAVE IS FORECAST TO MOVE ACROSS EASTERN CUBA TODAY. THE NORTHERN FRINGES OF THE WAVE COULD MOVE ACROSS SOUTH FLORIDA ON FRIDAY AND FRIDAY NIGHT...WHICH WOULD BRING ANOTHER CONVECTIVELY ACTIVE DAY FOR THE REGION. THE MID LEVEL RIDGE ACROSS SOUTH FLORIDA TODAY WILL BUILD NORTHWARD OVER CENTRAL FLORIDA FRIDAY INTO THE WEEKEND AND STRENGTHEN...ALLOWING A SOUTHEASTERLY FLOW TO DEVELOP. STREAMER SHOWERS MAY RETURN TO THE ATLANTIC WATERS AND EAST COAST METRO AREAS EACH MORNING...WITH SCATTERED TO NUMEROUS SEA BREEZE ACTIVITY IN THE AFTERNOON. MODEL GUIDANCE HAS PUSHED BACK THE ARRIVAL OF THE DRY AIR UNTIL SUNDAY NIGHT OR MONDAY. HOWEVER...AN OVERALL DRYING TREND WILL BEGIN ON SUNDAY ACROSS DEEP SOUTH FLORIDA AND THEN ACROSS THE REST OF THE REGION MONDAY THROUGH THE MIDDLE OF THE WEEK. TEMPERATURES ARE FORECAST TO BE NEAR NORMAL THROUGH THE PERIOD. AVIATION... A WEAK UPPER LEVEL DISTURBANCE...IN PART RELATED TO A SLIGHTLY DEEPENING SURFACE TROUGH ALONG THE SOUTHEAST COAST...WILL SLOWLY SINK SOUTH TODAY. THE SURFACE RIDGE OVER SOUTH FLORIDA YESTERDAY WILL WEAKEN EVER SO SLIGHTLY. THUS...WINDS WILL BE SOMEWHAT STRONGER FROM THE SW AND W THIS AFTERNOON. INITIALLY THIS MAY LEAD TO EARLIER AND MORE NUMEROUS STORMS THAN YESTERDAY NEAR KAPF. SO VCTS GROUP WAS MOVED UP A FEW HOURS THERE. ALSO...A SLIGHTLY STRONGER SW TO W WIND AND MORE DEVELOPMENT ALONG THE GULF COAST MAY PRODUCE QUICKER OR MORE NUMEROUS OUTFLOW BOUNDARIES...THAT CAN INTERACT WITH A SLIGHTLY STRONGER EAST COAST SEA BREEZE. IN CONCLUSION...VCTS WAS INCLUDED AT ALL TAF SITES...AND THE FEELING IS THAT COVERAGE WILL BE BETTER THAN YESTERDAY...WHICH CAN LEAD TO A SLIGHTLY GREATER CHANCE OF BRIEF IFR CONDS UNDER THE STRONGEST STORMS. MARINE... ATLANTIC WINDS ARE FORECAST TO SLOWLY TRANSITION TO A MORE SOUTHEASTERLY DIRECTION TODAY THROUGH THE WEEKEND...BUT REMAINING LIGHT. LATEST GUIDANCE INDICATES THAT LIGHT WESTERLY WINDS COULD PERSIST ACROSS PORTIONS OF THE GULF WATERS THURSDAY INTO FRIDAY. OTHERWISE...WINDS ARE FORECAST TO BE 10 KNOTS OR LESS THROUGH THE UPCOMING WEEKEND AND REGIONAL SEAS LESS THAN TWO FEET THROUGH THAT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 91 77 90 77 / 50 20 50 20 FORT LAUDERDALE 91 78 90 78 / 50 20 50 20 MIAMI 91 78 90 77 / 50 20 50 20 NAPLES 91 77 90 76 / 40 10 30 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS MIAMI FL
804 AM EDT THU AUG 7 2014 .AVIATION... MAINLY VFR CONDITIONS EXPECTED TO PREVAIL ACROSS ALL SOUTH FLORIDA TERMINALS THROUGH THE MORNING HOURS. CURRENTLY THE WINDS ACROSS THE REGION ARE LIGHT AND SOMEWHAT VARIABLE. AROUND THE 16-18Z TIME FRAME BOTH THE WEST AND EAST COAST SEA BREEZES EXPECTED TO FORM. SHOWERS/THUNDERSTORMS EXPECTED TO START AROUND 16Z-18Z WITH ALL TERMINALS ASSIGNED VCTS IN THAT TIME RANGE. STORM MOTION WILL BE SLOW AND SHOWERS/THUNDERSTORMS COULD FORM ALONG THE COASTAL ZONE WITH ALL TERMINALS POSSIBLY EXPERIENCING VERY BRIEF IFR CONDITIONS WITH SHOWERS/THUNDERSTORMS. 60 && .PREV DISCUSSION... /ISSUED 322 AM EDT THU AUG 7 2014/ DISCUSSION... EARLY WATER VAPOR IMAGERY AND RAP ANALYSIS SHOWED AN UPPER LOW NORTH OF MAINE...WITH THE UPPER TROUGH AXIS EXTENDING SOUTHWARD ACROSS THE COAST OF THE MID ATLANTIC AND INTO THE SOUTHEAST STATES. WEAK HIGH PRESSURE STRETCHED ACROSS SOUTH FLORIDA AND THE WESTERN ATLANTIC. A WEAK UPPER LEVEL DISTURBANCE OVER NORTHERN FLORIDA WILL DROP SLOWLY SOUTHWARD TOWARDS CENTRAL FLORIDA AND THE LAKE REGION THROUGH THE DAY. AT THE SURFACE...THE RIDGE IS SLIGHTLY WEAKER...BUT THE FLOW ABOVE SURFACE WILL BE LIGHT OUT OF THE WEST. THIS WILL ALLOW THE GULF COAST SEA BREEZE TO PUSH IN QUICKLY...WITH SHOWERS AND STORMS DEVELOPING ACROSS THE WEST EARLIER IN THE DAY...WITH OUTFLOW BOUNDARIES ALLOWING STORMS TO DEVELOP ALONG IN THE INTERIOR...AND THEN TOWARDS THE EAST COAST AS OUTFLOW BOUNDARIES INTERACT WITH THE SEA BREEZE. WITH THE WEAK UPPER DISTURBANCE...A MORE ACTIVE DAY OVERALL IS EXPECTED. A WEAK TROPICAL WAVE IS FORECAST TO MOVE ACROSS EASTERN CUBA TODAY. THE NORTHERN FRINGES OF THE WAVE COULD MOVE ACROSS SOUTH FLORIDA ON FRIDAY AND FRIDAY NIGHT...WHICH WOULD BRING ANOTHER CONVECTIVELY ACTIVE DAY FOR THE REGION. THE MID LEVEL RIDGE ACROSS SOUTH FLORIDA TODAY WILL BUILD NORTHWARD OVER CENTRAL FLORIDA FRIDAY INTO THE WEEKEND AND STRENGTHEN...ALLOWING A SOUTHEASTERLY FLOW TO DEVELOP. STREAMER SHOWERS MAY RETURN TO THE ATLANTIC WATERS AND EAST COAST METRO AREAS EACH MORNING...WITH SCATTERED TO NUMEROUS SEA BREEZE ACTIVITY IN THE AFTERNOON. MODEL GUIDANCE HAS PUSHED BACK THE ARRIVAL OF THE DRY AIR UNTIL SUNDAY NIGHT OR MONDAY. HOWEVER...AN OVERALL DRYING TREND WILL BEGIN ON SUNDAY ACROSS DEEP SOUTH FLORIDA AND THEN ACROSS THE REST OF THE REGION MONDAY THROUGH THE MIDDLE OF THE WEEK. TEMPERATURES ARE FORECAST TO BE NEAR NORMAL THROUGH THE PERIOD. AVIATION... A WEAK UPPER LEVEL DISTURBANCE...IN PART RELATED TO A SLIGHTLY DEEPENING SURFACE TROUGH ALONG THE SOUTHEAST COAST...WILL SLOWLY SINK SOUTH TODAY. THE SURFACE RIDGE OVER SOUTH FLORIDA YESTERDAY WILL WEAKEN EVER SO SLIGHTLY. THUS...WINDS WILL BE SOMEWHAT STRONGER FROM THE SW AND W THIS AFTERNOON. INITIALLY THIS MAY LEAD TO EARLIER AND MORE NUMEROUS STORMS THAN YESTERDAY NEAR KAPF. SO VCTS GROUP WAS MOVED UP A FEW HOURS THERE. ALSO...A SLIGHTLY STRONGER SW TO W WIND AND MORE DEVELOPMENT ALONG THE GULF COAST MAY PRODUCE QUICKER OR MORE NUMEROUS OUTFLOW BOUNDARIES...THAT CAN INTERACT WITH A SLIGHTLY STRONGER EAST COAST SEA BREEZE. IN CONCLUSION...VCTS WAS INCLUDED AT ALL TAF SITES...AND THE FEELING IS THAT COVERAGE WILL BE BETTER THAN YESTERDAY...WHICH CAN LEAD TO A SLIGHTLY GREATER CHANCE OF BRIEF IFR CONDS UNDER THE STRONGEST STORMS. MARINE... ATLANTIC WINDS ARE FORECAST TO SLOWLY TRANSITION TO A MORE SOUTHEASTERLY DIRECTION TODAY THROUGH THE WEEKEND...BUT REMAINING LIGHT. LATEST GUIDANCE INDICATES THAT LIGHT WESTERLY WINDS COULD PERSIST ACROSS PORTIONS OF THE GULF WATERS THURSDAY INTO FRIDAY. OTHERWISE...WINDS ARE FORECAST TO BE 10 KNOTS OR LESS THROUGH THE UPCOMING WEEKEND AND REGIONAL SEAS LESS THAN TWO FEET THROUGH THAT PERIOD. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 77 90 77 91 / 20 50 20 50 FORT LAUDERDALE 78 90 78 91 / 20 50 20 50 MIAMI 78 90 77 92 / 20 50 20 50 NAPLES 77 90 76 91 / 10 30 20 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...60/BD LONG TERM....30/KOB AVIATION...60/BD
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
742 AM EDT THU AUG 7 2014 .SYNOPSIS... A COLD FRONT WILL MOVE INTO THE FORECAST AREA TODAY AND STALL. THE FRONT WILL REMAIN IN THE AREA THROUGH THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... THE COLD FRONT SLOWLY PUSHING SOUTHWARD AND INTO THE FORECAST AREA TODAY WILL STALL TONIGHT. DESPITE CONVERGENCE ASSOCIATED WITH THE FRONT...THE THUNDERSTORM CHANCE IS LOW BECAUSE OF A LACK OF DEEP MOISTURE AND UPPER-LEVEL LIFT. THE NAM AND GFS DISPLAY SHALLOW MOISTURE WITH UPPER-LEVEL RIDGING. THE NAM AND GFS MOS HAVE POPS LESS THAN 20 PERCENT. THE 07Z HRRR DISPLAYS ISOLATED COVERAGE NEARING THE CSRA TOWARD 600 PM. THE 00Z SPC WRF SHOWS JUST ISOLATED COVERAGE MAINLY DURING THE EVENING. WE WILL GET OFF TO A WARM START AND SATELLITE TRENDS SHOW LITTLE CLOUDINESS IMMEDIATELY UPSTREAM. IT SHOULD BE HOT UNDER MOSTLY SUNNY SKIES. THE GUIDANCE CONSENSUS SUPPORTS HIGHS IN THE MIDDLE AND UPPER 90S. LOWS TONIGHT FALLING BACK DOWN TO AROUND 70. && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... THE NAM AND GFS INDICATE AN INCREASE IN MOISTURE ASSOCIATED WITH CONVERGENCE NEAR THE STALLED FRONT AND MOISTURE MOVING INTO THE AREA FROM THE WEST AS THE UPPER RIDGE FLATTENS. THE GUIDANCE CONSENSUS SUPPORTS CHANCE POPS. THE TEMPERATURE GUIDANCE WAS CLOSE. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... THE GFS AND ECMWF DISPLAY A STALLED FRONT WITH SIGNIFICANT MOISTURE IN THE FORECAST AREA THROUGH THE MEDIUM-RANGE PERIOD. THE GFS...ECMWF...AND EKE MOS POPS GENERALLY RANGE FROM 30 TO 60 PERCENT WITH THE HIGHER CHANCES SATURDAY AND SUNDAY. THE MODELS INDICATE PRECIPITABLE WATER OVER 2 INCHES SATURDAY AND SUNDAY SO HEAVY RAIN MAY OCCUR. THE MOS TEMPERATURES ARE CLOSE TO CLIMATOLOGY DURING THE PERIOD. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... MAINLY VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. JUST A FEW HIGH AND MID-LEVEL CLOUDS ACROSS THE AREA EARLY THIS MORNING. GIVEN THE LATEST OBSERVATIONAL TRENDS...WILL MENTION BRIEF MVFR VISIBILITIES AT AGS/OGB/CUB FOR AN HOUR. A FEW MORE CLOUDS AHEAD OF A WEAK FRONTAL SYSTEM WILL BEGIN MOVING INTO THE AREA BY THE LATE AFTERNOON. WINDS WILL BECOME NORTHWESTERLY AROUND 6-8 KNOTS INTO THE AFTERNOON HOURS...THEN GO BACK TO LIGHT AND VARIABLE BY LATE EVENING. EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE LATE FRIDAY THROUGH MONDAY IN SHOWERS AND THUNDERSTORMS AS A LOW PRESSURE SYSTEM SLOWLY CROSSES THE REGION. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
644 AM EDT THU AUG 7 2014 .SYNOPSIS... A WEAK BACK DOOR COLD FRONT WILL STALL ACROSS THE AREA LATE TONIGHT THROUGH FRIDAY...THEN LIKELY MOVE NORTH OF THE AREA ON SATURDAY. ANOTHER WEAK COLD FRONT COULD STALL ACROSS THE AREA BY MID NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE LATEST H3R AND RAP SHOW A RATHER EXPANSIVE AREA OF 100 DEG TEMPERATURES ACROSS THE INTERIOR THIS AFTERNOON. NOT QUITE READY TO GO THAT HIGH RIGHT NOW...BUT DID NUDGE HIGHS UP A DEGREE IN A FEW SELECT LOCATIONS. THE REST OF THE FORECAST IS ON TRACK. AN ILL-DEFINED LEE SIDE TROUGH WL MEANDER INTO THE AREA TDA AS MID-LEVEL HEIGHTS RISE SLGTLY AHEAD OF SHORTWAVE ENERGY MOVING INTO THE MID MS VALLEY. MODEST W/NW FLOW AHEAD OF THE SHORTWAVE COUPLED WITH FAVORABLE PSNG ALONG THE NRN PERIPHERY OF THE 590 DM ANTICYCLONE CNTRD OVR THE FL STRAIGHTS WL PIN THE SEA BREEZE TO THE BEACHES AGAIN THIS AFTN. 850 HPA TEMPS ARE FCST TO RISE TO +18-20C WHICH IS ABOUT 1-2C WARMER THAN 24 HRS AGO. XPCT A SLGTLY WARMER DAY AS A RESULT WITH HIGHS RANGING FROM THE UPR 90S INLAND TO AROUND 90 AT THE BEACHES. SOME OF THE 07/00Z COOP GUIDANCE SUPPORTS A FEW SPOTS REACHING 100 DEGS WHICH DOES NOT SEEM UNREASONABLE WITH SOME PRE-FNTL COMPRESSIONAL HEATING LIKELY TO OCCUR AHEAD OF AN APRCHG BACKDOOR CDFNT. DEWPTS ARE FCST TO MIX OUT ENOUGH DURING PEAK HEATING TO KEEP MAX HEAT INDICES 100-105 DEGS THIS AFTN...WHICH IS WELL BELOW THE LTE SUMMER HEAT ADV CRITERIA OF 110 DEGS. IT IS UNCLEAR HOW MUCH CONVECTION WL FIRE THIS AFTN GIVEN THE GENERALLY UNFAVORABLE SYNOPTIC SETUP. A DRY W/NW DOWNSLOPE FLOW TYPICALLY DOES NOT FAVOR SIGNIFICANT CONVECTION DVLPG OVER OR MOVING INTO THE FCST AREA WITHOUT SOME SORT OF STRONG IMPULSE MOVING ACROSS THE SRN APPALACHIANS OR SC UPSTATE DURING PEAK HEATING. WITH LTL TO NO LOW-LEVEL CONVG NOTED ALONG THE PINNED SEA BREEZE AND WEAK SUBSIDENCE/DNVA NOTED OVER THE AREA...SUSPECT ONLY VERY ISOLD SHWRS/TSTMS TO PSBLY FIRE ALONG OR VERY NEAR THE COAST. GRIDDED POPS WL BE CAPPED AT 5-10 PCNT FOR THE COASTAL ZONES WITH POPS 0-5 PCNT ELSEWHERE. LATER SHIFTS MAY VERY WELL NEED TO ADD A MENTIONABLE POP BACK INTO THE FCST ONCE SHORT TERM MESOSCALE SCALE TRENDS BECOME MORE APPARENT LTR TDA...BUT THERE JUST IS NOT ENOUGH EVIDENCE TO SUPPORT MENTIONABLE POPS ATTM. && .SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/... TONIGHT...A SHORTWAVE WL PROPAGATE ACROSS THE MID-ATLC STATES THIS EVNG...WHICH WILL HELP DRIVE A BACKDOOR CDFNT INTO THE SC LOWCOUNTRY AND EVENTUALLY THE COASTAL EMPIRE OF SE GA OVRNGT. THERE MAY BE JUST ENOUGH LOW-LEVEL CONVG ALONG THE LEADING EDGE OF THE FNT AND DPVA ASSOC WITH THE TAIL END OF THE SHORTWAVE TO SUPPORT ISOLD SHWRS/TSTMS ROUGHLY IN THE 9PM-3AM TIME FRAME. THE SYNOPTIC MID- LVL FLOW WL REMAIN UNFAVORABLE WITH W/NW TRAJS...BUT BOTH THE GFS AND NAM SHOW 700 HPA THETA-E...ROUGHLY 330-332K... POOLING ALONG AND AHEAD OF THE FNT WHICH MAY BE ENOUGH TO COUNTERACT THIS. WL FCST SLIGHT CHANCE POPS OVERNIGHT WITH GRIDDED POPS CAPPED AT 15-20 PCNT. IT WILL BE A FAIRLY SEASONABLE NGT FOR LTE SUMMER WITH LOWS RANGING FROM THE LWR-MID 70S INLAND...MID- UPR 70S AT THE COAST WITH UPR 70S-LWR 80S AT THE BEACHES AND DWTN CHARLESTON. FRIDAY...A WEAK BACKDOOR COLD FRONT WILL LIKELY BE ACROSS SOUTHEAST SOUTH CAROLINA BEFORE LIFTING NORTH AND WEAKENING THROUGHOUT THE DAY. TEMPS WILL BE SOMEWHAT DETERMINED BY THE POSITION OF THE FRONT BEFORE IT LIFTS NORTH...BUT IN GENERAL EXPECT TEMPS TO APPROACH THE LOW/MID 90S AWAY FROM THE COAST. AS THE FRONT LIFTS NORTH...FORCING WILL BE LIMITED OVER THE AREA...AND SHOWERS/THUNDERSTORMS SHOULD BE DEPENDENT MAINLY ON SFC HEATING. AS A RESULT...HAVE KEPT A RAIN-FREE FORECAST DURING MORNING HOURS...BEFORE MAINTAINING CHANCES OF SHOWERS AND/OR THUNDERSTORMS DURING PEAK HEATING. ACTIVITY SHOULD GRADUALLY DIMINISH FRIDAY NIGHT WITH THE LOSS OF DAYTIME HEATING. SATURDAY AND SUNDAY...A WETTER PATTERN SHOULD BE IN PLACE AS H5 SHORTWAVE APPROACHES THE SOUTHEAST AND SPAWNS A WEAK SFC LOW ALONG OR NEAR THE WEAKENED FRONT TO OUR NORTH. ANOTHER H5 SHORTWAVE IS THEN EXPECTED TO SWING AROUND THE MID LVL LOW POSITIONED TO OUR NORTH...CAUSING THE SFC LOW TO SLOWLY SHIFT TOWARD THE SOUTHEAST COAST BY SUNDAY AFTERNOON. DEEP MOISTURE CHARACTERIZED BY PWATS AT OR ABOVE 2 INCHES WILL BUILD AHEAD OF THE LOW AND SUPPORT SOLID CHANCES OF SHOWERS AND/OR THUNDERSTORMS INTO EARLY NEXT WEEK. TEMPS SHOULD REMAIN A FEW DEGREES COOLER THAN PREVIOUS DAYS GIVEN INCREASED CLOUD COVER AND CONVECTIVE ACTIVITY EXPECTED OVER THE AREA EACH AFTERNOON. IN GENERAL...AFTERNOON HIGHS SHOULD RANGE IN THE UPPER 80S TO LOWER 90S...WARMEST IN SOUTHEAST GEORGIA. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... A WETTER PATTERN SHOULD PERSIST INTO EARLY NEXT WEEK AS AREAS OF SFC LOW PRESSURE DEVELOP ALONG THE BASE OF A MID LVL TROUGH OF LOW PRESSURE SHIFTING OVER THE NORTHEASTERN UNITED STATES. PWATS AT OR ABOVE 2.0 INCHES SUPPORT CHANCES OF SHOWERS AND/OR THUNDERSTORMS EACH DAY...ESPECIALLY AS A ANOTHER COLD FRONT APPROACHES FROM THE NORTH AND STALLS OVER OR JUST SOUTH OF THE REGION BY MID WEEK. BEST CHANCES OF SHOWERS/THUNDERSTORMS SHOULD OCCUR IN SOUTHEAST GEORGIA NEAR THE VICINITY OF THE FRONT ONCE IT STALLS AND BEGINS TO DISSIPATE INTO LATE WEEK. OVERALL HIGH TEMPS SHOULD REMAIN NEAR NORMAL FOR THIS TIME OF YEAR...AROUND 90 DEGREES BUT WITH SLIGHT VARIATION IN SHOWERS AND THUNDERSTORMS. OVERNIGHT LOWS SHOULD RANGE IN THE LOW TO MID 70S AWAY FROM THE COAST. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... VFR. EXTENDED AVIATION OUTLOOK...A BRIEF PERIOD OF FLIGHT RESTRICTIONS IS POSSIBLE THROUGH FRIDAY AFTERNOON WITH SHOWERS AND THUNDERSTORMS DEVELOPING ALONG A NORTHWARD MOVING FRONT. CHANCES OF FLIGHT RESTRICTIONS WILL BE GREATER SATURDAY AND SUNDAY AS LOW PRESSURE DEVELOPS JUST NORTH OF THE AREA AND GRADUALLY SHIFTS TOWARDS THE SOUTHEAST COAST. && .MARINE... TODAY...NO CONCERNS. W/SW WNDS WL BACK TO THE S THIS AFTN AS A WEAK SEA BREEZE DVLPS RIGHT ALONG THE BEACHES. WINDS WL GENERALLY BE 10 KT OR LESS WITH SEAS 1-3 FT. TONIGHT...THE WND FIELD WL BECOME RATHER LGT AND CHAOTIC OVRNGT AS A BACKDOOR CDFNT DROPS S INTO THE WTRS. SEAS WL REMAIN 1-3 FT. FRIDAY THROUGH TUESDAY...A WEAK BACKDOOR COLD FRONT IS EXPECTED TO BE OVER NORTHERN SC WATERS INTO EARLY FRIDAY...BEFORE LIFTING NORTH OF THE WATERS BY EARLY SATURDAY. WINDS WILL BE VARIABLE AT OR BELOW 10 KTS INITIALLY NEAR THE FRONT...BUT WILL GRADUALLY BECOME SOUTH/SOUTHEAST ON SATURDAY...THEN SOUTH/SOUTHWEST SUNDAY THROUGH TUESDAY AS AREAS OF LOW PRESSURE PASS OFFSHORE JUST TO THE NORTH. EXPECT CONDITIONS TO REMAIN BELOW SMALL CRAFT ADVISORY LEVELS THROUGH EARLY NEXT WEEK...WITH WIND SPEEDS AT OR BELOW 15 KTS...HIGHEST NEAR AFTERNOON SEABREEZE CIRCULATIONS ALONG THE COAST. SEAS WILL GENERALLY RANGE BETWEEN 1-3 FT...HIGHEST IN OFFSHORE GEORGIA WATERS AND NORTHERN SC WATERS EARLY NEXT WEEK. && .TIDES/COASTAL FLOODING... THE PERIGEAN SPRING TIDES WILL BE PEAKING THIS WEEKEND...WITH HIGHER THAN NORMAL ASTRONOMICAL TIDES EXPECTED. WIND FIELDS WILL BE RELATIVELY LIGHT...WITH ONLY A SMALL IMPACT ON THE TIDES. HOWEVER...ONLY A SMALL DEPARTURE IS NEEDED ABOVE THE PREDICTED ASTRONOMICAL TIDES VALUES TO RESULT IN MINIMAL COASTAL FLOODING CRITERIA...ESPECIALLY FOR THE SC COAST. SHALLOW COASTAL FLOODING COULD OCCUR AS EARLY AS FRIDAY AND PERSIST INTO SUNDAY. && .CLIMATE... RECORD HIGHS FOR 7 AUGUST: KCHS 99/2008... KCXM 97/1899... KSAV 100/2008... && .EQUIPMENT... THE CHARLESTON SC RADAR /KCLX/ REMAINS OUT OF SERVICE DUE TO A SIGNIFICANT MECHANICAL FAILURE. THE CURRENT ESTIMATE HAS THE RADAR RETURNING TO SERVICE BETWEEN AUGUST 16TH AND 21ST. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT THU AUG 7 2014 .DISCUSSION... 324 AM CDT MAIN FORECAST CONCERNS CONTINUE TO FOCUS ON RAIN POTENTIAL ACROSS MAINLY SOUTHERN PARTS OF THE FORECAST AREA TONIGHT INTO FRIDAY. A FAIRLY VIGOROUS MID-LEVEL SHORT WAVE TROUGH WAS NOTED MOVING INTO THE MISSOURI RIVER VALLEY EARLY THIS MORNING PER GOES WATER VAPOR IMAGERY. IN ADDITION TO A MATURE MCS OVER MISSOURI AND NORTHEAST OKLAHOMA...AN AREA OF ELEVATED CONVECTION WAS OCCURRING IN THE REGION OF WARM ADVECTION MOIST ASCENT ACROSS DOWNSTATE ILLINOIS TO THE NORTH OF THE LOW LEVEL STATIONARY FRONT. ADDITIONAL WEAKER SHOWERS AND THUNDERSTORMS EXTENDED NORTHWEST ALONG THE ELEVATED BAROCLINIC ZONE ACROSS IOWA. MOST OF THIS ACTIVITY IS WELL SOUTH OF SOME OF THE MODEL FORECASTS FROM 24-30 HOURS AGO...AND CURRENT RUNS HAVE LARGELY CONVERGED ON A TREND TO KEEP MOST PRECIP TO THE SOUTHWEST OF THE WFO LOT CWA TODAY...AND ACROSS THE SOUTHERN COUNTIES OF THE CWA TONIGHT INTO FRIDAY. THE WRF-NAM CONTINUES TO DEVELOP SIGNIFICANT PRECIPITATION WELL NORTH OF THE MAIN BAROCLINIC ZONE AND HAS BEEN LARGELY DISCOUNTED IN FAVOR OF A BLEND OF THE GEM/GFS/ECMWF...WHICH KEEP HEAVIEST RAIN JUST SOUTH OF THE CWA ACROSS CENTRAL IL/IN THROUGH THE PERIOD. ADVECTION OF DRY AIR FROM THE EAST AND SOUTHEAST EAST AND SOUTHEAST SUGGESTS A FAIRLY SHARP NORTHERN CUTOFF IN PRECIP/QPF FIELDS...AND HAVE DEPICTED A FAIRLY TIGHT GRADIENT FROM DRY NORTH TO 40-60 PERCENT POPS SOUTH TONIGHT INTO FRIDAY WITH THE GREATEST CHANCES MAINLY SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. DESPITE MARGINAL MID-LEVEL LAPSE RATES LOCALLY HEAVY RAINFALL IS NOT OUT OF THE QUESTION WITH THE STRONGEST 850-700 MB THETA-E ADVECTION AND MOISTURE CONVERGENCE FOCUSED JUST SOUTH OF THE CWA WITH 1.8-2.0" PWATS. SLOWLY DAMPING MID-LEVEL WAVE CONTINUES TO TRACK EAST ACROSS IL/IN FRIDAY...WITH THE POTENTIAL FOR SOME LINGERING LIGHTER RAINFALL ACROSS THE SOUTHERN COUNTIES CLOSER TO THE BAROCLINIC ZONE. WEAK SUBSIDENCE BEHIND DEPARTING/WEAKENING DISTURBANCE ALLOWS WEAK SURFACE HIGH PRESSURE RIDGE TO STRENGTHEN SLIGHTLY ACROSS THE WESTERN LAKES FRIDAY NIGHT/SATURDAY...WITH ONLY WEAK MODEL SIGNALS OF SPOTTY PRECIP POTENTIAL AS WEAK REGION OF MID-LEVEL TROUGHING LINGERS FROM THE DAKOTAS TO THE SOUTHERN LAKES OVER THE WEEKEND. HAVE ELECTED TO MAINTAIN A DRIER FORECAST ALONG THE LINES OF THE 12/00Z ECMWF DURING THE WEEKEND WITH LITTLE SIGNIFICANT FORCING TO KEY ON AND GENERALLY DRY NORTHEASTERLY LOW LEVEL FLOW. LONG RANGE GUIDANCE DEVELOP A MORE AMPLIFIED UPPER TROUGH ACROSS THE MIDWEST MONDAY AND TUESDAY...WHICH SHOULD PRESENT A LITTLE GREATER THREAT OF PRECIP. AGAIN HAVE FAVORED THE WEAKER ECMWF SURFACE EVOLUTION AT THIS DISTANCE...AS OPPOSED TO THE GFS WHICH DEPICTS A DEEPENING SURFACE LOW OVER THE GREAT LAKES. WITH CONTINUED NORTHEAST-EAST SURFACE WINDS THROUGH THE PERIOD... SLIGHTLY COOLER THAN AVERAGE TEMPERATURES EXPECTED WITH MODEST AUGUST LAKE COOLING. HAVE GENERALLY ACCEPTED THE BLENDED BIAS CORRECTED TEMP GUIDANCE WHICH MAINTAINS HIGHS IN THE UPPER 70S/LOW 80S FOR THE MOST PART...WITH SOME MID-UPPER 70S WHERE THICKER CLOUD COVER OR PRECIP IS EXPECTED. MINS GENERALLY 60-65. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * EASTERLY WINDS 10 KT OR HIGHER WITH MID TEEN GUSTS THROUGH THE AFTERNOON...AND AGAIN BEGINNING FRIDAY MID MORNING. KMD //DISCUSSION...UPDATED 12Z... QUIET CONDITIONS CONTINUE THIS MORNING AS HIGH LEVEL CLOUD COVER CONTINUES TO STREAM OVERHEAD FROM THE SYSTEM TO THE SOUTHWEST. TRENDS CONTINUE WITH A MORE SOUTHERLY TRACK OF THIS SYSTEM DURING THE FORECAST PERIOD...WITH PRECIP NOT EXPECTED AND VFR CONDITIONS TO PERSIST. DID MAKE CHANGES TO WIND FORECAST...MOVING UP TIMING OF STRONGER SPEEDS AND INCLUDING GUSTS. SHORT TERM GUIDANCE AND AMDAR SOUNDINGS IN AGREEMENT WITH THIS SOONER ARRIVAL OF HIGHER SPEEDS OVER THE NEXT COUPLE OF HOURS...AND CONTINUING INTO THE AFTERNOON. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE WITH WIND SPEED/DIRECTION KMD //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...VFR. SATURDAY...VFR. SUNDAY...VFR. MONDAY...CHANCE OF TSRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 415 AM CDT WITH HIGH PRESSURE STRETCHED ACROSS THE REGION THIS MORNING...LIGHTER WINDS REMAIN IN PLACE OVER THE LAKE. EXPECT THESE LIGHTER SPEEDS IN THE 10 TO 15 KT RANGE TO CONTINUE TODAY AND MOST OF TONIGHT BEFORE A TREND TOWARDS SLIGHTLY HIGHER SPEEDS OCCURS...PRIMARILY OVER THE SOUTH HALF. A TROUGH OF LOW PRESSURE OVER THE CENTRAL PLAINS WILL SHIFT EAST TOWARDS THE MID MISSISSIPPI VALLEY THROUGH FRIDAY AND FRIDAY NIGHT. THIS WILL HELP SPEEDS INCREASE MORE TOWARDS THE 10 TO 20 KT RANGE LATE TONIGHT INTO FRIDAY MORNING...ONCE AGAIN FOR THE SOUTHERN HALF OF THE LAKE. GUIDANCE STILL VARIES TO THE NORTHERN EXTENT OF THIS LOWS TRACK BUT WITH LATEST TRENDS SUPPORTING A MORE SOUTHERLY TRACK...HELPING TO LIMIT SPEEDS AND ASSOCIATED WAVES FRIDAY AND FRIDAY NIGHT. DESPITE THIS MORE SOUTHERLY TRACK...STILL FEEL THAT A 10 TO 20 KT WIND IS PROBABLE...AND HAVE CONTINUED THIS MENTION IN THE FORECAST. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 944 AM CDT Thu Aug 7 2014 .UPDATE... ISSUED AT 934 AM CDT THU AUG 7 2014 Leading edge of the rain has been having difficulty making it past a Galesburg to Paris line, as some drier dew points around 60 degrees have been in place. Small area of dry weather around Springfield and Jacksonville has been eroding as the next batch of rain spreads in from the southwest. Latest HRRR guidance does not show a lot of northeast progression, and have maintained slight chance PoP`s along the northeast fringes of the forecast area this afternoon. The southwest CWA will see periodic rain through the day, while the southeast sees additional showers moving in after a short late morning break. Precipitable water values of around 1.8 to 1.9 inches will allow for locally heavy rain amounts, and the first batch of rain has already produced around an inch or so in the southwest corner of the CWA in a short time frame. && .SHORT TERM...(Today and tonight) ISSUED AT 251 AM CDT THU AUG 7 2014 Main forecast concern this period will be with the potential for heavy rainfall across west central through southern Illinois. A slow moving upper wave across the Missouri Valley will track across Missouri today and into Illinois by Friday. At the surface, a stalled frontal boundary remains south of our forecast area this morning and is not really expected to move much to the north. As the upper support tracks across Missouri, low pressure will move along the stalled frontal boundary to our south, enhancing the low level convergence along it and focusing the heavy rainfall threat across far west central through southern Illinois today through tonight. Forecast soundings continue to indicate weak instability and shear parameters, but precipitable water values are forecast to be around 2.10 inches which is well above normal, even for August standards in our area. Soundings, no matter what model you look at, indicate moisture content through the entire air column remains very impressive, with locally heavy rains from the slow moving thunderstorms, especially over extreme west central Illinois southeast into south central Illinois. With a persistent low level jet orientated perpendicular into the surface and 850 mb frontal boundary thru tonight, the threat for heavy rainfall is real. Warm cloud depths of over 13,000 feet indicate the thunderstorms will be very efficient rain makers with rainfall rates of 1-2 inches per hour possible wherever stronger storms concentrate. Rainfall totals through tonight will range from 1 to 2 inches along and south of a Rushville to Springfield to Mattoon line, with heavier totals possible near Jacksonville southwest. Areas over west central through southern Illinois can stand some heavy rainfall, at least initially, however, with the high precipitable water values focused along the stalled frontal boundary, flooding potential will remain a concern over our west and southern areas. Further north, big question is when and if rain gets into our northeast and far eastern areas today as high pressure to our north has drawn down some drier air and will effectively keep rain at bay, at least initially for today with only slight chance PoPs. As the upper wave edges across the state later tonight into early Friday, rain chances will increase across the northeast and far eastern counties. && .LONG TERM...(Friday through Wednesday) ISSUED AT 251 AM CDT THU AUG 7 2014 Low pressure will track into the Ohio River Valley on Friday, taking the strongest forcing further east out of the area. Will continue likely PoPs along/east of I-57 during the morning hours, with rain chances diminishing across the board as the day progresses. Models remain in poor agreement this weekend, with the GFS suggesting scattered showers/thunder both Saturday and Sunday as region remains within a band of sheared vorticity aloft. ECMWF is mostly dry, with surface high pressure building southward from the Upper Midwest/Great Lakes and lingering frontal boundary well to the south. Think GFS is being too aggressive with convective development, particularly in the absence of meaningful forcing, so have trended toward the drier ECMWF. As a result, have gone dry for both Saturday and Sunday with highs reaching the lower 80s. After that, a series of weak upper waves will once again dig a significant trough over eastern Canada/Great Lakes by the middle of next week. First wave and associated frontal boundary will swing through Illinois on Monday, accompanied by widely scattered thunder. Second wave will arrive on Tuesday. After that, high pressure will resume control of the weather across central Illinois, allowing a cooler/drier air mass to arrive by next Wednesday. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) ISSUED AT 600 AM CDT THU AUG 7 2014 Forecast challenges this period include precip coverage across the forecast area and affect on cigs/vsbys. Band of rain has shifted northeast to a Canton to Lincoln to Paris line with the northern edge mainly sprinkles out of a mid deck, while south of SPI, steadier rains has brought the cigs down to MVFR and even some local IFR cigs were reported over the past hour. May have to include some tempo MVFR cigs at SPI this morning with the steadier rains holding over that site, but further to the east and north, with a drier air mass in place, cigs may have a tough time dropping to MVFR range today. Best threat for thunder appears to be at SPI, at least for today with most areas seeing at least VCTS tonight. With better moisture transport further north late today and tonight, would think most areas will see MVFR cigs, except for BMI and CMI. Surface winds will be from an easterly direction thru the period with speeds of 10 to 15 kts today and from 6 to 11 kts tonight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...SMITH LONG TERM...BARNES AVIATION...SMITH
AREA FORECAST DISCUSSION
NWS DES MOINES IA
653 AM CDT THU AUG 7 2014 .SHORT TERM /TODAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 DIFFICULT FORECAST TODAY AS THE MODELS REALLY DO NOT HAVE A GOOD HANDLE ON WHAT IS GOING ON. ALOFT A SHORTWAVE IS SHIFTING ACROSS NORTHERN/CENTRAL MISSOURI. THERE IS GOOD MOISTURE TRANSPORT INTO THIS AREA INTERSECTING A FRONTAL BOUNDARY. HOWEVER THE MOISTURE IS HAVING A TOUGH TIME REACHING IOWA AS IT IS FEEDING THE STORMS IN MISSOURI. AS A RESULT WE HAVE NOT RECEIVED THE HEAVY RAINFALL PREVIOUSLY THOUGHT ACROSS FAR SOUTHERN IOWA THUS THE FLASH FLOOD WATCH WILL BE DROPPED WITH THE MORNING ISSUANCE. AT THE SURFACE...LOW PRESSURE OVER NORTHERN MISSOURI IS TIED TO THE AFOREMENTIONED FRONTAL BOUNDARY AND THIS IS PROGGED TO SLOWLY LIFT TO THE NORTHEAST TODAY. THE QUESTION IS HOW FAR NORTHEAST WILL IT GET. LATEST PROGS BARELY LIFT IT INTO SOUTHEAST IOWA THUS THE HEAVY RAINFALL POTENTIAL SHOULD STAY SOUTH AND EAST OF IOWA WHERE THE BETTER INSTABILITY WILL REMAIN. THERE WILL HOWEVER BE SOME WEAK KINEMATIC FORCING OVER IOWA TODAY THUS THE POTENTIAL FOR SHOWER/ISOLATED THUNDERSTORMS WILL REMAIN OVER MUCH OF THE CWA TODAY UNTIL THE SHORTWAVE AND SURFACE LOW PUSH EAST. AS FOR QPF...THE 06Z NAM WAS BETTER AT WITH ITS QPF FORECAST THAN THE 00Z RUN BUT IT SEEMS TO BE TIED TOO MUCH TO THE FORCING AND THE PAST COUPLE OF NIGHTS THE HEAVIER PRECIP WAS TIED MORE THE TO INSTABILITY AXIS. THE HOPWRF ALSO WAS ALSO PRETTY BULLISH ON PRECIP WHILE THE HRRR...WHICH HAD THE BEST HANDLE ON ONGOING PRECIP...SHOWED THE PRECIP TIED TO THE LOW AND FRONTAL BOUNDARY MAINLY IN MO WITH SCT PRECIP MORE OVER EASTERN IOWA INTO THE EASTERN PORTION OF OUR CWA. I LIKED THE HRRR THE BEST AND PREFER ITS SOLUTION BUT DID BLEND POPS WITH THE HOPWRF AND NEIGHBORING OFFICES. I KEPT THE HIGHEST POPS IN THE SOUTHEAST FROM LATE MORNING INTO THE AFTERNOON WITH CHANCE OR SLIGHT CHANCE POPS ELSEWHERE. NORTHEASTERN IOWA WAS SPARED FROM PRECIP YESTERDAY IN LARGE PART FROM THE HIGH PARKED TO THE NORTHEAST BUT AS THE LOW SHIFTS NORTHEAST THE SURFACE HIGH WILL PUSH EAST AND LOSE MUCH OF ITS INFLUENCE ON NORTHEASTERN PORTIONS OF THE CWA. I DID PUT A PERIOD OF CHANCE POPS IN FOR THE AFTERNOON BUT POP CHANCES SHOULD BE LOWEST IN THIS AREA. PATCHY FOG HAS DEVELOPED OVER MUCH OF THE CWA AND THIS WILL LIKELY HANG AROUND THROUGH A FAIR PART OF THE MORNING. SOUNDINGS ARE SHOWING A PERSISTENT EASTERLY COMPONENT TO THE WIND AND DEEP MOISTURE OVER CENTRAL IOWA THROUGH AT LEAST 15Z. TEMPS WILL ALSO BE COOLER TODAY WITH THE CLOUD COVER AND SCATTERED SHOWERS/STORMS. GENERALLY DROPPED HIGHS ACROSS THE CENTRAL SECTIONS AND KEPT THE NORTHEAST WARMER PRIMARILY DUE TO HIGHER CLOUD HEIGHTS...LOWER PRECIP CHANCES AND QPF. .LONG TERM /TONIGHT THROUGH WEDNESDAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 FORCING WILL PERSIST MAINLY IN THE EAST AND NORTH THIS EVENING WHERE LIGHT SCATTERED SHOWERS MAY LINGER. HOWEVER...THE FORCING WILL SUBSIDE DURING THE NIGHT WITH THE THREAT OF PRECIPITATION DIMINISHING OVERNIGHT. THE STATE WILL CONTINUE TO SEE WESTERLY FLOW ALOFT WITH EASTERLY SURFACE FLOW AS THE SURFACE FRONT REMAINS SOUTH AND WEST OF IOWA AND WEAK RIDGING SLIDING TO THE NORTH. THE RELATIVELY MOIST EASTERLY FLOW WILL LIKELY KEEP A GOOD AMOUNT OF CLOUDINESS AROUND ON FRIDAY INTO SATURDAY. THIS IS EXPECTED TO KEEP DIURNAL RANGES RELATIVELY LOW WITH DAYTIME HIGHS REMAINING BELOW NORMAL WITH LIMITED INSOLATION. DESPITE THE MOIST LOW LEVELS DURING THIS TIME...FORCING WILL BE WEAK OR NON-EXISTENT AND THEREFORE PRECIPITATION IS NOT EXPECTED ON FRIDAY OR SATURDAY. THE NEXT SYSTEM BEGINS TO APPROACH LATE IN THE WEEKEND BUT THE BULK OF FORCING WILL REMAIN TO THE NORTH. THIS WILL LIMIT THUNDERSTORMS CHANCES AND ANY STORMS THAT DO FORM WILL LIKELY BE SOMEWHAT UNORGANIZED AS SHEAR WILL REMAIN WEAK. THE REMAINDER OF THE EXTENDED APPEARS RELATIVELY DRY AFTER MONDAY WITH SOME MODERATION IN TEMPERATURES AS THE EASTERLY FLOW WEAKENS. && .AVIATION...07/12Z ISSUED AT 653 AM CDT WED AUG 6 2014 SFC LOW AND WARM FRONT SITUATED ACROSS NRN/CEN MO WILL SLOWLY SHIFT TO THE ENE THROUGH THE FCST PD. DEEP MOISTURE WILL ALSO REMAIN IN PLACE THROUGH THE FCST PD SO IFR/MVFR CIGS ARE EXPECTED. THERE WILL BE PERIODS OF SHOWERS AND AT LEAST ISOLD THUNDERSTORMS ESPECIALLY SOUTH AND EAST MAINLY THROUGH 00Z BEFORE PRECIP WANES. THE LOW CIGS WILL REMAIN AND THERE WILL LIKELY BE FOG DEVELOPING TONIGHT WHICH WILL LOWER VSBYS AS WELL. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...FAB LONG TERM...COGIL AVIATION...FAB
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
855 AM EDT Thu Aug 7 2014 ...Forecast Update... Issued at 855 AM EDT Thu Aug 7 2014 Quick update to the forecast this morning to account for the latest trends. As expected, the band of showers over southern IN has weakened over the past hour or so and should continue to do so through the remainder of the morning hours. Therefore, have trimmed pops back a bit for the rest of the morning hours. Also brought the forecast more in line with current obs. Issued at 640 AM EDT Thu Aug 7 2014 Continue to see rain showers north of a frontal boundary, stretching from central Illinois southeast to KOWB and with very light showers continuing southeast into our forecast area. Latest HRRR insists that these showers will dissipate over the next hour or two. Have a couple of areas of focus for additional development late this morning and through the afternoon hours. One will be north of the current band`s axis and the other will be over western KY. Still a question if lightning will occur with the cells near Louisville. Forecast soundings show the best instability above 700 mb, so any cells that develop would be elevated. Cannot rule out one or two strikes, so have put in isolated storms for the afternoon. Still think the more strikes will occur with storms that develop in the more unstable airmass over our southwest forecast area. .SHORT TERM (Now through Friday)... Issued at 315 AM EDT Thu Aug 7 2014 Early this morning a frontal boundary lies over the TN Valley. Some weak lift north of this front is resulting in a thin line of scattered showers from roughly KSTL TO KOWB. The GFS has this thin band bringing shower chances into the Louisville Metro throughout the day. Will go more optimistic than that as we should see a narrow ridge aloft stabilizing the atmosphere by this afternoon. As for the rest of the forecast area, still looks like the best chance for thunderstorms will reside west of the I-65 corridor and closer to the front to our south. This front will start lifting north as a warm front late tonight. Combine that surface forcing with an upper disturbance, now over Missouri, closer to the region as well as increasing precipitable waters should make for better rain chances late Thursday night. Storms look likely areawide for Friday as the warm front stalls somewhere over southern Indiana and low pressure rides up the lower Ohio Valley. Rainfall totals through Friday should average around an inch, with the highest amounts in our far western forecast area. .LONG TERM (Friday Night through Wednesday)... Issued at 315 AM EDT Thu Aug 7 2014 Friday Night - Saturday... Wet conditions look to continue Friday night and Saturday as a weak area of low pressure slowly moves across the Ohio Valley, interacting with a moist airmass. Will continue mention of scattered to numerous showers during these two periods. Best focus looks to be across the northern two-thirds of the CWA Friday night, and across the southeastern half on Saturday, although everyone has a pretty decent shot at getting in on the action. PWATs look to still be around or just below 2 inches through the column so expect the main threat with any shower or storm to be heavy rain. Cloud to ground lightning will also be a main concern for outdoor activities. Expect mild overnight lows on Friday night in the upper 60s in low 70s. Highs on Saturday will be dependent on convection, but low and mid 80s look reasonable. Saturday Night - Sunday Night... Shallow and weak NW flow aloft will remain in control of the area as we end the weekend, meanwhile a weak surface low will meander slowly just east of the area. This will keep the focus for shower and storm activity mainly east of I-65, although cannot rule out an isolated shower over the CWA on Saturday night and Sunday. Coverage mainly showers should be isolated to widely scattered at best over the Bluegrass during this time. Look for lows each night mainly in the upper 60s. A nice temperature gradient looks to set up for highs on Sunday with upper 80s SW to around 80 in our NE. Monday - Wednesday... An upper ridge will build more solidly over the western and central CONUS Monday through Wednesday. Meanwhile, an impulse will dive across the Great Lakes and combine with the weak low pressure just to our NE, helping to amplify a trough over the eastern CONUS. The Ohio Valley will find itself in the increasing NW flow aloft between these two features for the first half of next week. This will leave us in a drier overall pattern, however will likely have to deal with more diurnally driven convection, and/or any convection that may fire in response to passing waves embedded in the flow. Have depicted the best chances for isolated to scattered storm chances across our SE half of the CWA, with a drier atmosphere anticipated over our NW closer to a surface high. Model data supports a warm up in temperatures for the first half of the week, especially Tuesday and Wednesday. Have nudged the forecast closer to the upper 80s and low 90s for the SW half of the forecast area closer to the upper ridge. Being careful to get too aggressive as some of the rainfall advertised leading up to this time period, could limit our heating efficiency just a bit. && .AVIATION (12Z TAF Update)... Issued at 650 AM EDT Thu Aug 7 2014 Clouds actually have broken up some over KBWG, leading to lower vsby down there that at the other sites, where mid/upper clouds are thicker. Have removed tempo groups for the other sites and put one in for a few hours at KBWG. Increasing moisture may be enough for some widely scattered showers and storms, with the best chance over KBWG late this afternoon. A few models are showing a narrow band of isolated showers/storms closer to KSDF in the afternoon. Only have enough confidence to put in some storms over KBWG late this afternoon, and will monitor trends to see if we need to put this in for KSDF or not. The system driving the storms this morning over Missouri will be closer to us late tonight. Thus we will have a better chance for some rains late in the period for KSDF and KBWG. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....RJS Long Term......BJS Aviation.......RJS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
651 AM EDT Thu Aug 7 2014 ...Updated Aviation Discussion... ...Forecast Update... Issued at 640 AM EDT Thu Aug 7 2014 Continue to see rain showers north of a frontal boundary, stretching from central Illinois southeast to KOWB and with very light showers continuing southeast into our forecast area. Latest HRRR insists that these showers will dissipate over the next hour or two. Have a couple of areas of focus for additional development late this morning and through the afternoon hours. One will be north of the current band`s axis and the other will be over western KY. Still a question if lightning will occur with the cells near Louisville. Forecast soundings show the best instability above 700 mb, so any cells that develop would be elevated. Cannot rule out one or two strikes, so have put in isolated storms for the afternoon. Still think the more strikes will occur with storms that develop in the more unstable airmass over our southwest forecast area. .SHORT TERM (Now through Friday)... Issued at 315 AM EDT Thu Aug 7 2014 Early this morning a frontal boundary lies over the TN Valley. Some weak lift north of this front is resulting in a thin line of scattered showers from roughly KSTL TO KOWB. The GFS has this thin band bringing shower chances into the Louisville Metro throughout the day. Will go more optimistic than that as we should see a narrow ridge aloft stabilizing the atmosphere by this afternoon. As for the rest of the forecast area, still looks like the best chance for thunderstorms will reside west of the I-65 corridor and closer to the front to our south. This front will start lifting north as a warm front late tonight. Combine that surface forcing with an upper disturbance, now over Missouri, closer to the region as well as increasing precipitable waters should make for better rain chances late Thursday night. Storms look likely areawide for Friday as the warm front stalls somewhere over southern Indiana and low pressure rides up the lower Ohio Valley. Rainfall totals through Friday should average around an inch, with the highest amounts in our far western forecast area. .LONG TERM (Friday Night through Wednesday)... Issued at 315 AM EDT Thu Aug 7 2014 Friday Night - Saturday... Wet conditions look to continue Friday night and Saturday as a weak area of low pressure slowly moves across the Ohio Valley, interacting with a moist airmass. Will continue mention of scattered to numerous showers during these two periods. Best focus looks to be across the northern two-thirds of the CWA Friday night, and across the southeastern half on Saturday, although everyone has a pretty decent shot at getting in on the action. PWATs look to still be around or just below 2 inches through the column so expect the main threat with any shower or storm to be heavy rain. Cloud to ground lightning will also be a main concern for outdoor activities. Expect mild overnight lows on Friday night in the upper 60s in low 70s. Highs on Saturday will be dependent on convection, but low and mid 80s look reasonable. Saturday Night - Sunday Night... Shallow and weak NW flow aloft will remain in control of the area as we end the weekend, meanwhile a weak surface low will meander slowly just east of the area. This will keep the focus for shower and storm activity mainly east of I-65, although cannot rule out an isolated shower over the CWA on Saturday night and Sunday. Coverage mainly showers should be isolated to widely scattered at best over the Bluegrass during this time. Look for lows each night mainly in the upper 60s. A nice temperature gradient looks to set up for highs on Sunday with upper 80s SW to around 80 in our NE. Monday - Wednesday... An upper ridge will build more solidly over the western and central CONUS Monday through Wednesday. Meanwhile, an impulse will dive across the Great Lakes and combine with the weak low pressure just to our NE, helping to amplify a trough over the eastern CONUS. The Ohio Valley will find itself in the increasing NW flow aloft between these two features for the first half of next week. This will leave us in a drier overall pattern, however will likely have to deal with more diurnally driven convection, and/or any convection that may fire in response to passing waves embedded in the flow. Have depicted the best chances for isolated to scattered storm chances across our SE half of the CWA, with a drier atmosphere anticipated over our NW closer to a surface high. Model data supports a warm up in temperatures for the first half of the week, especially Tuesday and Wednesday. Have nudged the forecast closer to the upper 80s and low 90s for the SW half of the forecast area closer to the upper ridge. Being careful to get too aggressive as some of the rainfall advertised leading up to this time period, could limit our heating efficiency just a bit. && .AVIATION (12Z TAF Update)... Issued at 650 AM EDT Thu Aug 7 2014 Clouds actually have broken up some over KBWG, leading to lower vsby down there that at the other sites, where mid/upper clouds are thicker. Have removed tempo groups for the other sites and put one in for a few hours at KBWG. Increasing moisture may be enough for some widely scattered showers and storms, with the best chance over KBWG late this afternoon. A few models are showing a narrow band of isolated showers/storms closer to KSDF in the afternoon. Only have enough confidence to put in some storms over KBWG late this afternoon, and will monitor trends to see if we need to put this in for KSDF or not. The system driving the storms this morning over Missouri will be closer to us late tonight. Thus we will have a better chance for some rains late in the period for KSDF and KBWG. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update......... Short Term.....RJS Long Term......BJS Aviation.......RJS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
722 AM EDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM EDT THU AUG 7 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG AXIS EXTENDING FM MN INTO NW ONTARIO...WITH SFC HI PRES ELONGATED FM JAMES BAY INTO FAR WRN LK SUP. VERY DRY/STABLE MID LVLS SHOWN ON THE LOCAL 00Z RAOBS AND THE LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE RDG HAVE RESULTED ARE BRINGING MOCLR SKIES TO THE CWA. WITH LGT WINDS UNDER THE MOCLR SKIES...SOME PATCHY FOG HAS FORMED. THERE IS A SHRTWV JUST E OF LK WINNIPEG THAT IS LIFTING SLOWLY NEWD...AND THERE ARE SOME BKN MID/HI CLDS OVER NW MN AND FAR NW ONTARIO. TEMPS/RH/FIRE WX PARAMETERS ARE THE MAIN FCST CONCERNS IN THE SHORT TERM AS UPR RDG/SFC HI PRES ARE FCST TO DOMINATE THRU TNGT. TODAY...SFC HI PRES IS FCST TO CENTER OVER THE E HALF OF LK SUP AS UPR RDG SHIFTS TO AN AXIS FM UPR MI TO JAMES BAY. EXCEPT FOR SOME SCT CU ALONG AND INLAND FM LK BREEZE BNDRYS THAT DVLP UNDER THE RATHER FLAT PRES GRADIENT AS WELL AS SOME PATCHY HI CLDS WELL TO THE S OF SHRTWV LIFTING NEWD THRU ONTARIO...THE DAY WL FEATURE PLENTY OF SUNSHINE. WITH H85 TEMPS FCST TO PEAK AT 13-14C OVER THE W THIS AFTN...SIMILAR TO YDAY...EXPECT MAX TEMPS RISING INTO THE 70S/LO 80S AWAY FM THE LK MODERATION...WHICH WL BE ENHANCED NEAR THE BAY OF GREEN BAY AND ALONG LK SUP E OF THE KEWEENAW IN THE E H925 FLOW. SFC DEWPTS SHOULD MIX OUT AS LO AS THE UPR 40S THIS AFTN...RESULTING IN MIN RH DOWN TO 30-35 PCT AWAY FM LK MODERATION. DESPITE RECENT DRYNESS AT MANY LOCATIONS...LIGHT WINDS WL MITIGATE THE FIRE WX THREAT. TNGT...WITH SFC HI PRES REMAINING OVER THE E HALF OF LK SUP...EXPECT DRY WX. ALTHOUGH MID LVL DRY AIR WL REMAIN IN PLACE...SOME HI CLDS MAY DRIFT THRU THE UPR LKS ON THE SRN FLANK OF SHRTWV LIFTING TOWARD JAMES BAY. TEMPS OVER THE INTERIOR SHOULD STILL BOTTOM OUT IN THE 40S...COOLEST OVER THE INTERIOR E CLOSER TO THE HI AND LIGHTER H925 WINDS. ADDED SOME PATCHY FOG OVER THE INTERIOR CENTRAL AND E...WHERE EXPECTED MIN TEMPS ARE LIKELY TO FALL AOB CROSS OVER DEWPTS THIS AFTN. A BIT STRONGER S WIND AT H925 WL LIMIT THE DIURNAL FALL OVER THE W. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 345 AM EDT THU AUG 7 2014 MAIN ISSUES DURING THE LONG TERM WILL BE CONTINUED DRY WEATHER THROUGH THE WEEKEND WITH THE NEXT CHANCE OF RAIN PUSHING IN AHEAD OF A COLD FRONT FOR THE FIRST PART OF THE WORKWEEK. FRIDAY THROUGH SATURDAY...BROAD SURFACE RIDGING ALONG WITH UPPER LEVEL 500MB RIDGING WILL REMAIN IN PLACE ACROSS MUCH OF THE UPPER GREAT LAKES REGION THROUGH AS WELL AS MUCH OF THE EASTERN CONUS THROUGH THIS TIME FRAME. DRY WEATHER WILL BE THE RULE UNDER THE RIDGE AS MOISTURE ADVECTION WILL BE LIMITED WITH VERY LOW DEEP LAYER 1000-500MB RH VALUES. THE SURFACE HIGH WILL SLOWLY SHIFT TO THE EAST DURING THE DAY SATURDAY. THIS WILL KEEP LIGHT WINDS IN THE FORECAST WITH THE STRONGEST GUSTS EXPECTED TO BE ALONG LAKE BREEZE BOUNDARIES DURING THE AFTERNOON HOURS. CONDITIONS ARE BECOMING VERY DRY ACROSS MUCH OF THE U.P. AS THERE HAS BEEN VERY MINIMAL PRECIPITATION OVER THE PAST COUPLE WEEKS. THIS HAS ALLOWED BOTH SOIL AND VEGETATION TO BECOME DRY. DECENT MIXING CONDITIONS ARE EXPECTED TO OCCUR EACH AFTERNOON THROUGH THIS TIME PERIOD...WHICH WILL LEAD TO INCREASED FIRE DANGER...FORTUNATELY...WINDS WILL CONTINUE TO BE FAIRLY LIGHT AS PREVIOUSLY MENTIONED. HAVE KEPT LOWER AFTERNOON DEWPOINTS IN PLACE AS DRIER AIR ALOFT MIXES DOWN TO THE SURFACE WITH AFTERNOON HEATING. TEMPERATURES WILL CONTINUE TO WARM THROUGH THIS PERIOD WITH 850MB TEMPS WARMING FROM NEAR 13C THURSDAY AFTERNOON TO AROUND 14C BY SATURDAY AFTERNOON AS THE HIGH CONTINUES THE SLOW TREK EASTWARD. SATURDAY NIGHT THROUGH THE REMAINING EXTENDED...THE NEXT UPPER LEVEL TROUGH AND DEVELOPING SURFACE LOW ARE PROGGED TO BE NEAR THE JUST NORTH OF LAKE WINNIPEG SATURDAY NIGHT WITH A COLD FRONT STRETCHING SOUTHWESTWARD ACROSS THE DAKOTAS AS SHOWN BY ANALYZING 850 THETA E ALONG WITH SURFACE WINDS. THIS WILL BE THE MAIN FOCUS FOR SHOWER AND THUNDERSTORM ACTIVITY. THE LOW WILL SHIFT EASTWARD TO NORTHERN QUEBEC BY MONDAY AFTERNOON AS THE FRONT DRAPES ACROSS THE UPPER GREAT LAKES REGION. RIGHT NOW THE BEST CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY WOULD BE LATE SUNDAY NIGHT OVER WESTERN UPPER MI AND DURING THE DAY MONDAY ACROSS MOST OF UPPER MI. DEEP LAYER FORCING SHOULD BE PLENTIFUL ALONG THE FRONT TO ALLOW PRECIPITATION TO DEVELOP ACROSS THE AREA AS SHOWN BY OVERLAYING QCONV ALONG WITH 1000-500MB RH. THIS WILL ALSO BE AROUND THE SAME TIME THAT THE UPPER LEVEL 500MB TROUGH AXIS SWINGS ACROSS THE AREA HELPING TO KEEP INSTABILITY HIGH ENOUGH FOR CONTINUED THUNDERSTORM CHANCES. MOISTURE WILL NOT BE OVERLY ABUNDANT THEREFORE WILL KEEP THE BEST CHANCE POPS RIGHT ALONG AND JUST AHEAD OF THE FRONT ALONG THE FAIRLY NARROW RIBBON OF MOISTURE. THE FRONT IS PROGGED TO BE EAST OF THE AREA BY TUESDAY...HOWEVER...UPPER LEVEL TROUGHING AND LINGERING MOISTURE NEARBY...WOULD EXPECT SHOWERS TO LINGER THROUGH AT LEAST TUESDAY MORNING. DRY HIGH PRESSURE WILL BUILD IN AT THE SURFACE TUESDAY NIGHT AND LINGER THROUGH WEDNESDAY AS UPPER LEVEL 500MB HEIGHT RISES BEGIN TO PUSH BACK INTO THE UPPER PENINSULA. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 722 AM EDT THU AUG 7 2014 EXPECT VFR CONDITIONS THIS FCST PERIOD AT ALL 3 TAF SITES WITH DRY HI PRES DOMINATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 AM EDT THU AUG 7 2014 HI PRES WILL DOMINATE THE UPPER GREAT LAKES THROUGH THIS WEEKEND... WITH LIGHT WINDS BELOW 15 KTS AND WAVES GENERALLY LESS THAN 2 FT. AFTER THE HI FINALLY MOVES OFF TO THE E...A COLD FRONT WILL CROSS LAKE SUPERIOR ON MON. N WINDS MAY INCREASE UP TO 20 KTS FOLLOWING THIS FRONTAL PASSAGE AND IN ADVANCE OF THE NEXT HI PRES BUILDING OVER ONTARIO. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KEC AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
632 AM CDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CDT THU AUG 7 2014 THE MODELS SHOW MOISTURE POOLING ACROSS SWRN NEB EARLY THIS EVENING WITH PRECIPITABLE WATER INCREASING TO AROUND 1.5 INCHES. ITS A LIKELY POP SITUATION AS THE H500MB RIDGE FLATTENS AND A DISTURBANCE ACROSS SWRN WY MOVES EAST SOUTHEAST THROUGH SWRN NEB TONIGHT. THE FCST DELAYS POPS BY 3 HOURS GIVEN THE BIAS IN MODEL TIMING WHICH BRINGS THE BEST RAIN CHANCES THIS EVENING AND OVERNIGHT WHICH IS MORE IN LINE WITH THE QPF FORECAST. HPC CARRIES THE BEST QPF MORE SOUTH THRU SWRN NEB THEN WRN KANSAS BUT THE RAP AND NAM CORFIDI VECTORS FOR A FORWARD PROPAGATING MCS SHOW EASTWARD MOTION WHICH SUPPORTS THE BLENDED QPF FORECAST WE HAVE PREPARED. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 357 AM CDT THU AUG 7 2014 MODELS ARE IN BETTER AGREEMENT IN THE EXTENDED THAN PREVIOUS RUNS WITH THE OVERALL PATTERN. SOUTHERN UPPER LEVEL RIDGE ON FRIDAY WILL BUILD NORTHWEST ACROSS THE ROCKIES OVER THE WEEKEND AS A LOW MOVES ACROSS TOWARDS CENTRAL CAL AND A TROUGH DIGS ACROSS THE GREAT LAKES. MODELS STALL THE CLOSED LOW ACROSS WESTERN CAL WITH THE RIDGE CONTINUING TO BUILD TOWARDS MONTANA BY TUESDAY. THE WESTERN LOW THEN LIFTS NORTH AND BEGINS TO FLATTEN THE RIDGE. PERIODIC CHANCES FOR RAIN PERSIST THROUGH MUCH OF THE FORECAST. OVER THE WEEKEND SEVERAL DISTURBANCES WILL RIDE NORTH OF THE RIDGE. TIMING OF THE WAVES VARIES BETWEEN THE MODELS AND FORECAST WILL RETAIN LOW CHANCE POPS THROUGH THE WEEKEND. WHILE POPS ARE IN NEARLY EVERY PERIOD OVER THE WEEKEND...NOT EXPECTING IT TO BE A WASH OF A WEEKEND. DEVELOPMENT ACROSS THE FRONT RANGE WITH ACTIVITY SLIDING EAST/SOUTHEAST ACROSS THE CWA. THERE WILL ALSO BE SOME ISOLATED LATE DAY ACTIVITY DUE TO A WEAKENING CAP DUE TO PLENTIFUL BL MOISTURE. THE RICH BL MOISTURE WILL ALSO NEED TO BE MONITORED FOR LATE NIGHT/MORNING PATCHY FOG. TEMPS OVER THE WEEKEND WILL BE SEASONALLY COOL /LOWER TO MID 80S/ DURING THE DAY AND MILD OVERNIGHT /LOWER TO MID 60S. AS WE START THE WORK WEEK...FLOW BECOMES M0RE NORTHWESTERLY. MODELS CONTINUE A TRAIN OF SHORT WAVES AROUND THE RIDGE...HOWEVER THEY BECOME SPACED OUT MORE. STILL GOING TO SEE OCCASIONAL POPS WITH EACH WAVE...AND TIMING IS HIGHLY UNCERTAIN THIS FAR OUT. WITH THE RIDGE BUILDING TO THE WEST...TEMPS SHOULD CLIMB A LITTLE. GUIDANCE IS IN THE MID AND UPPER 80S...WHICH IS CLOSER TO SEASONAL NORMS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 630 AM CDT THU AUG 7 2014 SATELLITE AND ANALYSIS OF THE SFC TO 3000FT WINDS SUGGESTS WEAK OR NEUTRAL MOISTURE ADVECTION AND EVEN SIGNS OF DIVERGENCE WHICH WOULD INDICATE THE IFR/MVFR CIGS SHOULD LIFT TO VFR 15Z-18Z ACROSS MUCH OF THE FCST AREA. KONL AND AREAS EAST MAY REMAIN IN MVFR UNTIL MID AFTN. TSTMS DEVELOP AND BECOME NUMEROUS FROM WEST TO EAST LATE THIS AFTERNOON THROUGH AT LEAST 05Z TONIGHT AND THEN BECOME ISOLATED. STORM COVERAGE IS MOSTLY FAVORED ALONG AND SOUTH OF NEBRASKA HIGHWAY 2. MVFR/IFR CIGS ARE EXPECTED TO RETURN FROM 06Z ONWARD. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1027 AM EDT THU AUG 7 2014 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL BRING VARIABLY CLOUDY CONDITIONS TO THE NORTH COUNTRY TODAY...WITH SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS. CLEARING SKIES ARE EXPECTED TONIGHT AS THE UPPER LEVEL DISTURBANCE SHIFTS EAST OF THE REGION. HIGH PRESSURE WILL BRING PLEASANT WEATHER FRIDAY AND THROUGH THE WEEKEND. AFTERNOON HIGH TEMPERATURES IN THE 70S TODAY AND FRIDAY WILL REBOUND TO THE LOW TO MID 80S OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1027 AM EDT THURSDAY...GOING FORECAST IN GOOD SHAPE WITH JUST A FEW TWEAKS TO HOURLY TEMPS AND POPS FOR THIS AFTERNOON. HAVE OPTED TO BUMP DOWN POPS FROM LIKELY IN THE NEK TO MENTION SCATTERED SHOWERS AND ONLY ISOLATED THUNDERSTORMS FOR THIS AFTERNOON INSTEAD AS LATEST GUIDANCE IS POINTING TO LESS INSTABILITY THAN BEFORE. ADDITIONALLY...BEST SHORTWAVE ENERGY AND PVA LOOKS TO BE OVER THE REGION THIS MORNING AND SHIFTING SOUTHWARD THROUGH THE DAY WHICH WON`T ALIGN AS WELL WITH THE BEST INSTABILITY DURING PEAK AFTERNOON HEATING. STILL THINK WE`LL SEE SCATTERED SHOWERS AND A FEW STORMS...SOME OF WHICH COULD PRODUCE SOME SMALL HAIL ( RAP ANALYSIS SHOWS -20C AT 500MB ACROSS NERN NY WITH CORE OF THERMAL TROUGH...WHICH IS DEFINITELY CHILLY FOR EARLY AUGUST. THE 700-500MB LAPSE RATES ARE 7.0-7.5 C/KM. THE BTV-4KM AND 12KM WRF RUNS INDICATE THAT SHOWER AND THUNDERSTORM ACTIVITY WILL BE MOST WIDESPREAD ACROSS VT. LIKEWISE...SPC CALIBRATED SREF TSTM PROBABILITIES SHOW THE GREATEST POTENTIAL ACROSS CENTRAL/ERN VT BETWEEN 18-21Z TODAY (40-50 PERCENT CHANCE OF TSTMS DURING THIS 3-HR PERIOD). GIVEN CAPE VALUES OF 500-1000 J/KG AND THE THERMAL MID-LEVEL TROUGH CONTRIBUTING TO WBZ HEIGHTS OF ONLY 6-7 KFT...CAN/T RULE OUT SOME ISOLATED 0.25-0.50" DIAMETER HAIL WITH ANY STRONGER CORES ACROSS THE NORTH COUNTRY DURING THIS AFTERNOON. MARGINAL CAPE (50S SFC DEWPOINTS) AND SFC-6KM BULK SHEAR GENERALLY LESS THAN 20 KTS SHOULD PRECLUDE ANY SEVERE THREAT. SUNSHINE WILL BE RATHER INTERMITTENT/LIMITED. COMBINED WITH THERMAL TROUGH IN PLACE (850MB TEMPS OF +8 TO +9C)...SHOULD HOLD AFTN HIGHS TO THE LOW-MID 70S FOR MOST SECTIONS. SFC WINDS WILL BE NW AROUND 10 MPH FOR MOST OF THE DAYLIGHT HRS. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/... AS OF 329 AM EDT THURSDAY...WITH ANTICIPATED CONVECTION GENERALLY DRIVEN BY STEEP LAPSE RATES AND PBL HEATING...ANTICIPATE ACTIVITY WILL WANE QUICKLY THIS EVENING WITH SKIES BECOMING MOSTLY CLEAR OVERNIGHT. THIS SHOULD SET UP GOOD POTENTIAL FOR NOCTURNAL FOG IN THE FAVORED RIVER VALLEYS 04-12Z FRIDAY...WITH OVERNIGHT LOWS IN THE UPPER 40S TO LOWER 50S FOR MOST SECTIONS. UPPER TROUGH WILL BE PULLING AWAY FROM THE REGION THROUGH THE CANADIAN MARITIMES ON FRIDAY. 700-500MB HEIGHTS PROGRESSIVELY RISE FROM W-E THROUGH THE DAY AS DEEP-LAYER RIDGE OVER THE GREAT LAKES TRANSLATES SLOWLY EASTWARD. STILL SOME WEAKLY CYCLONIC FLOW IN PLACE ACROSS THE NORTHEAST KINGDOM OF VERMONT...WHERE WE/VE KEPT A 20 POP FOR A STRAY DAYTIME SHOWER. OTHERWISE...SHOULD SEE PARTLY TO MOSTLY SUNNY CONDITIONS. P-GRADIENT IS WEAK...BUT SHOULD CONTINUE TO SEE PREVAILING NW WINDS 5-10 MPH FROM LATE MORNING THRU AFTERNOON WITH BOUNDARY LAYER MIXING. 850MB TEMPS BEGIN TO RECOVER AS WELL WITH EWD DEPARTURE OF THERMAL TROUGH. LOOKING AT VALLEY HIGHS GENERALLY IN THE UPR 70S FOR FRIDAY. FRIDAY NIGHT AND SATURDAY LOOK QUIET WITH HIGH PRESSURE BUILDING IN FROM THE GREAT LAKES. GOOD RADIATIONAL COOLING WILL LEAD TO NOCTURNAL FOG IN THE FAVORED VALLEYS 04-12Z SATURDAY WITH LIGHT AND VARIABLE WIND CONDITIONS. LOWS GENERALLY LOW-MID 50S...EXCEPT LOCALLY IN THE MID-UPR 40S IN THE NORMALLY COOLER SPOTS WITHIN THE NRN ADIRONDACKS AND NORTHEAST KINGDOM. A PLEASANT DAY SATURDAY WITH NEARLY FULL SUN (JUST A FEW CUMULUS CLOUDS TO DOT THE HIGHER TERRAIN DURING THE AFTERNOON HOURS). LIGHT NW WINDS AROUND 5 MPH EXPECTED. HIGHS SATURDAY WILL REBOUND INTO THE LOW 80S...BUT HUMIDITY LEVELS WILL REMAIN MODEST AS DEWPOINTS REMAIN IN THE MID- UPR 50S. POPS NIL FRIDAY NIGHT AND SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 342 AM EDT THURSDAY...SFC HIGH PRESSURE COMBINED WITH RIDGING ALOFT WILL LEAD TO A PLEASANT WEEKEND WITH DRY WARM CONDITIONS. 850MB TEMPERATURES AROUND 12C-14C SUNDAY WILL INCREASE TO 14C-15C. THIS WILL RESULT IN DAYTIME MAXES RANGING FROM THE U60S IN THE MOUNTAINS TO M80S IN THE VALLEYS...AND MORNING MIN TEMPERATURES IN THE 50S TO L60S. SFC HIGH PRESSURE SLIDES EAST INTO THE ATLANTIC AS UPPER RIDGE CRESTS OVER THE NORTHEAST MONDAY...AHEAD OF A COLD FRONT POISED TO MOVE ACROSS THE REGION MID WEEK. BEST POTENTIAL FOR PRECIPITATION ASSOCIATED WITH THE FROPA WILL BE LATE TUESDAY INTO WEDNESDAY WITH SHOWERS AND THUNDERSTORMS. PWATS INCREASE TO OVER 1.5 INCHES AHEAD OF THE FRONT IN WARM MOIST S TO SW FLOW. UPPER TROUGH ASSOCIATED WITH THIS SYSTEM WILL KEEP LINGERING SHOWERS OVER THE NORTH COUNTRY WEDNESDAY NGT INTO THURSDAY. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... THROUGH 12Z FRIDAY...SOME RESIDUAL LOW LEVEL MOISTURE THIS MORNING WILL RESULT IN MVFR/IFR CIGS AT KSLK/KMPV AND KBTV...BUT CIGS WILL LIFT BY 13Z/14Z AND EXPECT GENERALLY VFR LOW AND MID LVL CLOUDS THIS MORNING. UPPER LVL ENERGY ASSOCIATED WITH UPPER TROUGH WILL PRODUCE ISOLATED TO SCT SHOWERS MID-LATE MORNING INTO THE EVENING HRS. INSTABILITY AND CAPE WILL DEPEND ON DAYTIME HEATING/SUNSHINE...RESULTING IN PSBL THUNDER MAINLY IN THE AFTERNOON. SHOWERS DWINDLE IN THE LATE EVENING HOURS WITH GENERALLY CLEARING SKIES. BR/FG DEVELOPMENT PSBL AFTER 05Z...ESP AT KSLK AND KMPV. LIGHT WINDS INCREASE OUT OF THE NW TO 6-12KTS TODAY...SUBSIDING AFTER SUNSET TO LIGHT TO CALM. OUTLOOK 12Z FRIDAY THROUGH MONDAY... 12Z FRI - 00Z TUE...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG/BR POSSIBLE EACH NIGHT...ESPECIALLY AT KSLK AND KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...BANACOS NEAR TERM...BANACOS/LAHIFF SHORT TERM...BANACOS LONG TERM...KGM AVIATION...KGM
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
730 AM EDT THU AUG 7 2014 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE WILL BRING VARIABLY CLOUDY CONDITIONS TO THE NORTH COUNTRY TODAY...WITH SCATTERED SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON HOURS. CLEARING SKIES ARE EXPECTED TONIGHT AS THE UPPER LEVEL DISTURBANCE SHIFTS EAST OF THE REGION. HIGH PRESSURE WILL BRING PLEASANT WEATHER FRIDAY AND THROUGH THE WEEKEND. AFTERNOON HIGH TEMPERATURES IN THE 70S TODAY AND FRIDAY WILL REBOUND TO THE LOW TO MID 80S OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 724 AM EDT THURSDAY...A SHORTWAVE TROUGH/MID-LEVEL VORT CENTERED 75MI NE OF MONTREAL QUEBEC PER 11Z IR IMAGERY WILL BE THE CONTROLLING WEATHER FEATURE ACROSS THE NORTH COUNTRY TODAY. LEADING BAND OF DIFFERENTIAL CYCLONIC VORTICITY ADVECTION BROUGHT PRE-DAWN SHOWERS ACROSS VT...WHICH ARE NOW EXITING/WEAKENING ACROSS WINDSOR COUNTY. EXPECTATION IS THAT ADDITIONAL CLOUDS AND SHOWERS WILL FORM LATE THIS MORNING INTO THE AFTERNOON HRS AS A RESULT OF STEEP LOW- MID LEVEL LAPSE RATES WITH THERMAL TROUGH ALOFT AND INSOLATIONAL HEATING. LATEST RAP ANALYSIS SHOWS -20C AT 500MB ACROSS NERN NY WITH CORE OF THERMAL TROUGH...WHICH IS DEFINITELY CHILLY FOR EARLY AUGUST. THE 700-500MB LAPSE RATES ARE 7.0-7.5 C/KM. THE BTV-4KM AND 12KM WRF RUNS INDICATE THAT SHOWER AND THUNDERSTORM ACTIVITY WILL BE MOST WIDESPREAD ACROSS VT. LIKEWISE...SPC CALIBRATED SREF TSTM PROBABILITIES SHOW THE GREATEST POTENTIAL ACROSS CENTRAL/ERN VT BETWEEN 18-21Z TODAY (40-50 PERCENT CHANCE OF TSTMS DURING THIS 3-HR PERIOD). GIVEN CAPE VALUES OF 500-1000 J/KG AND THE THERMAL MID-LEVEL TROUGH CONTRIBUTING TO WBZ HEIGHTS OF ONLY 6-7 KFT...CAN/T RULE OUT SOME ISOLATED 0.25-0.50" DIAMETER HAIL WITH ANY STRONGER CORES ACROSS THE NORTH COUNTRY DURING THIS AFTERNOON. MARGINAL CAPE (50S SFC DEWPOINTS) AND SFC-6KM BULK SHEAR GENERALLY LESS THAN 20 KTS SHOULD PRECLUDE ANY SEVERE THREAT. SUNSHINE WILL BE RATHER INTERMITTENT/LIMITED. COMBINED WITH THERMAL TROUGH IN PLACE (850MB TEMPS OF +8 TO +9C)...SHOULD HOLD AFTN HIGHS TO THE LOW-MID 70S FOR MOST SECTIONS. SFC WINDS WILL BE NW AROUND 10 MPH FOR MOST OF THE DAYLIGHT HRS. WITH ANTICIPATED CONVECTION GENERALLY DRIVEN BY STEEP LAPSE RATES AND PBL HEATING...ANTICIPATE ACTIVITY WILL WANE QUICKLY THIS EVENING WITH SKIES BECOMING MOSTLY CLEAR OVERNIGHT. THIS SHOULD SET UP GOOD POTENTIAL FOR NOCTURNAL FOG IN THE FAVORED RIVER VALLEYS 04-12Z FRIDAY...WITH OVERNIGHT LOWS IN THE UPPER 40S TO LOWER 50S FOR MOST SECTIONS. && .SHORT TERM /FRIDAY THROUGH SATURDAY/... AS OF 329 AM EDT THURSDAY...UPPER TROUGH WILL BE PULLING AWAY FROM THE REGION THROUGH THE CANADIAN MARITIMES ON FRIDAY. 700-500MB HEIGHTS PROGRESSIVELY RISE FROM W-E THROUGH THE DAY AS DEEP-LAYER RIDGE OVER THE GREAT LAKES TRANSLATES SLOWLY EASTWARD. STILL SOME WEAKLY CYCLONIC FLOW IN PLACE ACROSS THE NORTHEAST KINGDOM OF VERMONT...WHERE WE/VE KEPT A 20 POP FOR A STRAY DAYTIME SHOWER. OTHERWISE...SHOULD SEE PARTLY TO MOSTLY SUNNY CONDITIONS. P-GRADIENT IS WEAK...BUT SHOULD CONTINUE TO SEE PREVAILING NW WINDS 5-10 MPH FROM LATE MORNING THRU AFTERNOON WITH BOUNDARY LAYER MIXING. 850MB TEMPS BEGIN TO RECOVER AS WELL WITH EWD DEPARTURE OF THERMAL TROUGH. LOOKING AT VALLEY HIGHS GENERALLY IN THE UPR 70S FOR FRIDAY. FRIDAY NIGHT AND SATURDAY LOOK QUIET WITH HIGH PRESSURE BUILDING IN FROM THE GREAT LAKES. GOOD RADIATIONAL COOLING WILL LEAD TO NOCTURNAL FOG IN THE FAVORED VALLEYS 04-12Z SATURDAY WITH LIGHT AND VARIABLE WIND CONDITIONS. LOWS GENERALLY LOW-MID 50S...EXCEPT LOCALLY IN THE MID-UPR 40S IN THE NORMALLY COOLER SPOTS WITHIN THE NRN ADIRONDACKS AND NORTHEAST KINGDOM. A PLEASANT DAY SATURDAY WITH NEARLY FULL SUN (JUST A FEW CUMULUS CLOUDS TO DOT THE HIGHER TERRAIN DURING THE AFTERNOON HOURS). LIGHT NW WINDS AROUND 5 MPH EXPECTED. HIGHS SATURDAY WILL REBOUND INTO THE LOW 80S...BUT HUMIDITY LEVELS WILL REMAIN MODEST AS DEWPOINTS REMAIN IN THE MID-UPR 50S. POPS NIL FRIDAY NIGHT AND SATURDAY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AS OF 342 AM EDT THURSDAY...SFC HIGH PRESSURE COMBINED WITH RIDGING ALOFT WILL LEAD TO A PLEASANT WEEKEND WITH DRY WARM CONDITIONS. 850MB TEMPERATURES AROUND 12C-14C SUNDAY WILL INCREASE TO 14C-15C. THIS WILL RESULT IN DAYTIME MAXES RANGING FROM THE U60S IN THE MOUNTAINS TO M80S IN THE VALLEYS...AND MORNING MIN TEMPERATURES IN THE 50S TO L60S. SFC HIGH PRESSURE SLIDES EAST INTO THE ATLANTIC AS UPPER RIDGE CRESTS OVER THE NORTHEAST MONDAY...AHEAD OF A COLD FRONT POISED TO MOVE ACROSS THE REGION MID WEEK. BEST POTENTIAL FOR PRECIPITATION ASSOCIATED WITH THE FROPA WILL BE LATE TUESDAY INTO WEDNESDAY WITH SHOWERS AND THUNDERSTORMS. PWATS INCREASE TO OVER 1.5 INCHES AHEAD OF THE FRONT IN WARM MOIST S TO SW FLOW. UPPER TROUGH ASSOCIATED WITH THIS SYSTEM WILL KEEP LINGERING SHOWERS OVER THE NORTH COUNTRY WEDNESDAY NGT INTO THURSDAY. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... THROUGH 12Z FRIDAY...SOME RESIDUAL LOW LEVEL MOISTURE THIS MORNING WILL RESULT IN MVFR/IFR CIGS AT KSLK/KMPV AND KBTV...BUT CIGS WILL LIFT BY 13Z/14Z AND EXPECT GENERALLY VFR LOW AND MID LVL CLOUDS THIS MORNING. UPPER LVL ENERGY ASSOCIATED WITH UPPER TROUGH WILL PRODUCE ISOLATED TO SCT SHOWERS MID-LATE MORNING INTO THE EVENING HRS. INSTABILITY AND CAPE WILL DEPEND ON DAYTIME HEATING/SUNSHINE...RESULTING IN PSBL THUNDER MAINLY IN THE AFTERNOON. SHOWERS DWINDLE IN THE LATE EVENING HOURS WITH GENERALLY CLEARING SKIES. BR/FG DEVELOPMENT PSBL AFTER 05Z...ESP AT KSLK AND KMPV. LIGHT WINDS INCREASE OUT OF THE NW TO 6-12KTS TODAY...SUBSIDING AFTER SUNSET TO LIGHT TO CALM. OUTLOOK 12Z FRIDAY THROUGH MONDAY... 12Z FRI - 00Z TUE...VFR UNDER HIGH PRESSURE. EARLY MORNING IFR FOG/BR POSSIBLE EACH NIGHT...ESPECIALLY AT KSLK AND KMPV. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...BANACOS NEAR TERM...BANACOS SHORT TERM...BANACOS LONG TERM...KGM AVIATION...KGM
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1017 AM CDT THU AUG 7 2014 .UPDATE... A DYING MCS CONTINUES TO MOVE TOWARD THE MIDSOUTH. A FEW SHOWERS AND THUNDERSTORMS ON THE LEADING EDGE HAVE MOVED INTO NORTHEAST ARKANSAS AND THE MO BOOTHEEL AT THIS TIME. THE MCS IS ASSOCIATED WITH AN UPPER TROF THAT WILL MOVE INTO THE MIDSOUTH TODAY. THE LATEST HRRR AND 12Z NAM SHOW CONVECTION EITHER CONTINUING OR REDEVELOPING IN ASSOCIATION WITH THIS TROF. WOULD EXPECT BY EARLY THIS AFTERNOON TO SEE NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE AT LEAST THE NORTHWEST HALF OF THE CWA. THE LIKELY POPS LOOK GOOD. HIGH TEMPERATURES MAY BE A TAD HIGH IF THE CONVECTION OCCURS LIKE THE MODELS ARE SHOWING BUT FOR NOW WILL LEAVE HIGH TEMPS ALONE. CURRENT FORECAST LOOKS GOOD...NO UPDATES ARE EXPECTED AT THIS TIME. KRM && .DISCUSSION... /ISSUED 324 AM CDT THU AUG 7 2014/ CURRENT WEATHER TONIGHT IS CLOSE TO A COPY AS IT GETS FROM LAST NIGHT. THE ONLY DIFFERENCE IS A SLOWLY APPROACHING MCS IN SOUTHWEST MISSOURI. TEMPERATURES ARE IN THE UPPER 60S TO MID 70S WITH CALM OR LIGHT WINDS. FOR TODAY THROUGH SATURDAY...MODELS ARE IN GOOD AGREEMENT THAT THE AFOREMENTIONED MCS/APPROACHING PLAINS SHORTWAVE WILL SLOWLY MOVE ACROSS THE MIDSOUTH THROUGHOUT THE DAY...WITH LIKELY REDEVELOPMENT IN NORTHWEST FLOW ON THE UPWIND SIDE TONIGHT AND TOMORROW. IT APPEARS THE BRUNT OF THE RAINFALL WILL FALL ACROSS THE NORTHERN TWO THIRDS OF THE CWA. INCREASING BOUNDARY LAYER MOISTURE TODAY WILL DRIVE CURRENT PW`S NEAR 1.50 INCHES...TO ABOVE 2 INCHES BY TONIGHT...THEN HOLD CLOSE TO 2 INCHES FOR MOST OF THE AREA THROUGH THE WEEKEND. FOR NOW KEEPING ANY FLASH FLOODING MORE LOCALIZED AS SEVERAL MIDSOUTH COUNTIES HAVE NOT HAD A GOOD SOAKING RAIN IN OVER TWO WEEKS. IN ADDITION THE POTENTIAL FOR STRONG AND SEVERE STORMS WILL BE SEEN DURING EACH AFTERNOON AND EVENING AS CAPE VALUES CLIMB TO 3000 J/KG AND LI`S DIP TO NEAR -10C. THOUGH THE ATMOSPHERE WILL NOT BE AS CONDUCIVE FOR LARGE HAIL FORMATION...IT WILL BE FOR DOWNBURSTS AND STRAIGHT LINE WINDS. TEMPERATURES WILL REMAIN SEASONAL TODAY...BECOMING SLIGHTLY BELOW NORMAL FOR TOMORROW AND SATURDAY. HIGH HUMIDITY THROUGH THE PERIOD WILL GENERATE AFTERNOON HEAT INDICES IN THE MID 90S...TO LOW 100S. SUNDAY THROUGH WEDNESDAY...THE GFS AND EURO HAVE SIMILAR SOLUTIONS THIS PERIOD WITH DIFFERENCES IN TIMING...CURRENTLY THE GFS IS FASTER. A DEEPER TROUGH IS ANTICIPATED TO DEVELOP OVER THE EASTERN THIRD OF THE COUNTRY. THIS IN TURN WILL ALLOW FOR A WEAK COLD FRONT TO SLIP THROUGH THE MIDSOUTH. DUE TO THE EXPECTED WORKED OVER ATMOSPHERE FROM THE CONVECTION EARLIER IN THE WEEKEND...AND SLIGHTLY DRIER AND MORE STABLE AIR WORKING IT`S WAY SOUTH AND EAST...RAIN CHANCES SHOULD SLOWLY TAPER OFF EACH DAY. TEMPERATURES WILL CHANGE LITTLE EARLY NEXT WEEK WITH HIGHS STAYING A DEGREE OR TWO BELOW NORMAL. JAB && .AVIATION... 12Z TAF CYCLE (07/12Z-08/12Z) SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL SPREAD INTO AND DEVELOP ACROSS THE MIDSOUTH LATE THIS MORNING AND AFTERNOON...AND PERSIST THROUGH TONIGHT AS AN UPPER LEVEL TROUGH MOVES OVER THE REGION ENCOUNTERING A MOIST AND UNSTABLE ATMOSPHERE. PUT TEMPO GROUPS IN THIS AFTERNOON FOR TSRA AT KMEM...KMKL...AND KJBR WHEN AND WHERE CONFIDENCE OF OCCURRENCE IS GREATEST. OUTSIDE SHOWERS AND THUNDERSTORMS...CONDITIONS WILL BE PREDOMINATELY VFR TODAY...THEN LOWERING TO MVFR AT KJBR AND KMKL TONIGHT. WINDS S-SW 5-9 KTS TODAY AND 3-6 KTS TONIGHT...VARIABLE AND STRONGER IN THUNDERSTORMS. JCL && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1030 AM CDT THU AUG 7 2014 .UPDATE... SOUTHWEST WINDS AT THE SURFACE THIS MORNING HAS WARMED UP TEMPERATURES A BIT FASTER THAN ANTICIPATED. CURRENT READINGS ARE ABOUT 1-3 DEGREES WARMER THAN THIS TIME YESTERDAY. WILL BUMP UP HIGHS A DEGREE OR TWO. THE HRRR CONTINUES TO OVERDO ITS CONVECTION FORECAST AND WILL LEAVE THE FORECAST DRY. OTHERWISE...NO MAJOR CHANGES TO THE CURRENT FORECAST. HAMPSHIRE && .PREV DISCUSSION... /ISSUED 637 AM CDT THU AUG 7 2014/ AVIATION... /12Z TAF DISCUSSION/ INTERMITTENT MVFR CIGS ARE EXPECTED TO AFFECT I-35 TERMINAL SITES FROM 09Z TO 15Z THE NEXT COUPLE MORNINGS. DAYTIME SOUTHERLY WINDS WILL BE UP TODAY OVER PREVIOUS DAYS SINCE A SHALLOW UPPER TROUGH WILL BE PASSING FROM THE GREAT BASING INTO THE CENTRAL PLAINS. PREV DISCUSSION... /ISSUED 347 AM CDT THU AUG 7 2014/ SHORT TERM (TODAY THROUGH FRIDAY)... A SMALL PATCH OF MVFR STRATOCUMULUS HAS DEVELOPED ACROSS THE COASTAL PLAINS THIS MORNING. WE EXPECT THIS TO SPREAD INLAND ABOUT TO I-35...THEN SCATTER OUT QUICKLY BY MID- MORNING WITH DAYTIME MIXING. A SIMILAR PATTERN OF CLOUD DEVELOPMENT AND POSSIBLY PATCHY FOG IS EXPECTED FRIDAY AND SATURDAY MORNINGS AS WELL. OTHERWISE... THE UPPER LEVEL RIDGE IS IN PLACE AND SHOULD LIMIT ANY CONVECTION TO VERY ISOLATED...SHORT-LIVED SHOWERS. TEMPERATURES WILL CONTINUE TO RUN ABOVE NORMAL IN THE UPPER 90S TO NEAR 100. LONG TERM (FRIDAY NIGHT THROUGH WEDNESDAY)... THE MODELS ARE IN GOOD AGREEMENT WITH MOVING A TUTT LOW NORTHWESTWARD ALONG THE RIO GRANDE IN MEXICO OVER THE WEEKEND. WE INCLUDED A 20 PCT POP FOR THE RIO GRANDE PLAINS TO COVER THIS SATURDAY EVENING AND SUNDAY. THE UPPER LEVEL RIDGE GETS STRONGER EARLY NEXT WEEK...SO EXPECT THE HOTTEST DAY(S) OF THE SUMMER MONDAY AND TUESDAY. THE RIDGE THEN SHIFTS WEST OVER THE ROCKIES AS A NEW TROUGH IS CARVED OUT OVER THE GREAT LAKES. THE GFS INDICATES A SHORT-WAVE TROUGH MAY DROP OUT OF THE MEAN LONGWAVE TROUGH AND BRING SOME RAIN AUGUST 15-17TH...BUT THE ECMWF DOES NOT SHOW THAT...SO WE WILL KEEP THE FORECAST DRY FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 100 76 99 75 98 / - - - - - AUSTIN BERGSTROM INTL AIRPORT 100 73 100 72 98 / - - - - - NEW BRAUNFELS MUNI AIRPORT 101 73 100 72 99 / - - - - - BURNET MUNI AIRPORT 100 74 98 73 97 / - - - - - DEL RIO INTL AIRPORT 102 78 101 77 98 / 10 - - - - GEORGETOWN MUNI AIRPORT 99 75 98 74 97 / - - - - - HONDO MUNI AIRPORT 100 73 98 72 97 / - - - - - SAN MARCOS MUNI AIRPORT 100 73 99 73 98 / - - - - - LA GRANGE - FAYETTE REGIONAL 99 76 98 75 97 / 10 - - 10 - SAN ANTONIO INTL AIRPORT 100 76 98 76 97 / - - - - - STINSON MUNI AIRPORT 100 75 99 74 98 / - - - - - && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...09 SYNOPTIC/GRIDS...29 PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
429 AM MDT THU AUG 7 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 427 AM MDT THU AUG 7 2014 A GOOD FETCH OF MONSOON MOISTURE PERSISTS ACROSS THE CWA THIS AM WITH A STRONG UPPER LOW OVER THE GREAT BASIN. THE LLVLS ARE QUITE MOIST YET AGAIN WITH WIDESPREAD SFC DEWPOINTS IN THE 50S TO NEAR 60F OVER THE HIGH PLAINS. MAIN CONCERN IN THE NEAR TERM WOULD BE FOG AND/OR LOW STRATUS OVER WESTERN NE WITH TEMP-DEWPOINT SPREADS LESS THAN 2 DEG. NAM BUFKIT SOUNDINGS FOR CDR AND SNY SHOW CIGS IMPROVING AFTER 15Z BUT STILL INDICATE LLVL SATURATION. A LOT OF CLOUD COVER TODAY...SO SLASHED FCST HIGHS TODAY BY SEVERAL DEGREES AS IT WILL BE TOUGH TO GET FAR INTO THE 80S WITH PCPN INCREASING BY EARLY AFTN. STILL LOOKING FOR AN UPTICK IN SHOWER/TSTM ACTIVITY DURING THE AFTN AND EVE. GFS/NAM/ECMWF ALL SHOW A SMALL PIECE OF MIDLVL ENERGY EMANATING FROM THE PARENT TROUGH OVER THE SOUTHWEST US. DECENT UPPER-LEVEL DIFFLUENCE OVER EASTERN ZONES WITH A MODEST 60 KT H25 JET MOVING OVERHEAD. SHOULD SEE SCT COVERAGE OF STORMS FOR MOST AREAS AS MIDLVL RH PROGS SHOW DEEP MOISTURE OVER MUCH OF THE REGION BY 00Z FRI. PER EARLIER COORDINATION WITH SPC...WE DO HAVE A 5 PCT RISK AREA FOR ISOLATED SEVERE ALONG AND NORTH OF THE I80 CORRIDOR EAST OF CHEYENNE. NAM HAS BEEN CONSISTENTLY SHOWING POCKETS OF 1500 TO 2000 J/KG CAPES OVER THE PLAINS WHICH COULD AID A FEW STRONG TO LOCALLY SEVERE STORMS YET AGAIN. NOT SURE HOW MUCH ORGANIZATION WE WILL SEE THOUGH AS BETTER DEEP LAYER SHEAR IS SPOTTY AT BEST WITH GENERALLY WEAK MIDLVL FLOW...SO WENT WITH MENTION OF SMALL HAIL AND GUSTY WINDS AS OPPOSED TO SEVERE IN THE GRIDS. EFFICIENT RAINERS EXPECTED WITH GFS PWATS APPROACHING 1.5 INCHES AND K-INDEX VALUES NEAR 40C OVER THE SOUTHERN PANHANDLE WITH MOIST SOUTHEAST LLVL FLOW. THE MODELS KEY IN ON A NUMBER OF WEAK DISTURBANCES ALOFT OVER THE AREA DURING THE OVERNIGHT. QPF RETURNS DEFINITELY COME DOWN...BUT WITH GOOD 700-300 MILLIBAR MOISTURE CONFIDENCE IS HIGH THAT A FEW LIGHT SHOWERS WILL CONTINUE BEYOND 06Z...MAINLY NORTHEAST. EXPECT ANOTHER ROUND OF FOG AND LOW CLOUDS OVER THE PANHANDLE AS NEAR-SFC RH VALUES RISE TO NEAR 100 PCT BY 12Z FRI. WILL HAVE TO SEE WHERE THE HEAVIER PCPN FALLS BEFORE WE CAN PIN DOWN THE LOCATIONS SEEING THE BEST CHANCE OF THIS. YET ANOTHER WAVE IS PROGGED TO MOVE INTO CENTRAL WY AFTER 15Z FRI. LIKE PREVIOUS DAYS...PCPN COVERAGE WILL PEAK DURING THE AFTN AND EARLY EVE. ISOLATED SEVERE STORMS CANNOT BE RULED OUT WITH MODERATE CAPES AHEAD OF DRYLINE ALONG THE WY/NE BORDER. SFC DEWPOINTS ARE PROGGED TO BE IN THE 60S AT 00Z SAT ACROSS PARTS OF THE PANHANDLE. THINKING FRIDAY MAY BE THE DAY TO SEE MORE ORGANIZED STORMS AS MORE WIDESPREAD H5 FLOW AROUND 30 KTS ENHANCES SHEAR. PERSISTENCE IS THE NAME OF THE GAME ON SAT... THOUGH THE BEST CHANCE FOR CONVECTION WILL BE CONFINED TO EASTERN AREAS AS UPPER-LEVEL RIDGING BUILDS INTO THE CWA. A LITTLE WARMER ALOFT EARLY IN THE WEEKEND WITH LESS OVERALL PCPN COVERAGE...SO EXPECT HIGHS TO BE A LITTLE WARMER THAN THU-FRI. .LONG TERM...(SUNDAY THROUGH THURSDAY) ISSUED AT 427 AM MDT THU AUG 7 2014 DAILY AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL BE THE MAIN STORY THROUGH THE LONG TERM FORECAST PERIOD. MODELS CONTINUE TO SHOW MONSOON MOISTURE OVER THE AREA DURING THE PERIOD BUT TIMING AND PLACEMENT OF EMBEDDED IMPULSES ON ANY GIVEN DAY IS IN MUCH QUESTION. CONFIDENT THERE WILL BE AT LEAST A FEW SHOWERS AND THUNDERSTORMS NEARLY EVERYDAY BUT COVERAGE AND PLACEMENT IS IMPOSSIBLE TO PINPOINT AT THIS TIME. DIURNAL PATTERN WILL BE THE MAIN DRIVER OF CONVECTION WITH MOST SHOWER AND THUNDERSTORM ACTIVITY DYING OFF BY MIDNIGHT MOST DAYS. WITHOUT SHORTWAVE ENERGY PASSING OVER THE AREA AT NIGHT MEASURABLE PRECIPITATION WILL BE TOUGH TO COME BY. THAT SAID THE ECMWF DOES MOVE A SHORTWAVE ACROSS THE PANHANDLE OF NEBRASKA MONDAY NIGHT. NOT BUYING OFF ON THAT SOLUTION 100 PERCENT AT THIS TIME BUT SHOULD THE SOLUTION VERIFY THERE WOULD BE A HIGHER CHANCE OF SHOWERS AND THUNDERSTORMS CONTINUING INTO THE OVERNIGHT. OTHERWISE THROUGH THE PERIOD TEMPERATURES WILL BE CLOSE TO THE SEASONAL NORMS WITH HIGHS MAINLY IN THE 80S WITH SOME 90S POSSIBLE IN THE EAST. LOWS WILL MOSTLY BE IN THE 50S TO LOWER 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY EVENING) ISSUED AT 1038 PM MDT WED AUG 6 2014 CONVECTION HAS NEARLY COME TO AN END ACROSS SOUTHEAST WYOMING AND THE NEBRASKA PANHANDLE. REMNANT CELLS CONTINUE NEAR THE WYOMING/COLORADO STATE LINE. MOST OF THE PANHANDLE HAS SEEN MEASURABLE RAINFALL THIS PAST EVENING AND WITH SKIES CLEARING OUT...CONFIDENCE IS GROWING THAT WE WILL SEE LOW CLOUDS AND POSSIBLY FOG DEVELOPING. HRRR SHOWS THIS REALLY WELL AND FOLLOWED ITS GUIDANCE. KCDR AND KAIA SHOULD FALL TO IFR/VLIFR AFTER 09Z OR SHORTLY THERE AFTER. CONVECTION RETURNS THURSDAY AFTERNOON AND COULD PERSIST WELL INTO THE EVENING HOURS. && .FIRE WEATHER... ISSUED AT 427 AM MDT THU AUG 7 2014 AN UNSETTLED WEATHER PATTERN WILL KEEP FIRE WEATHER CONCERNS AT A MINIMUM THROUGH AT LEAST THE WEEKEND. MONSOON MOISTURE WILL YIELD DAILY CHANCES FOR SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON AND EVENING HOURS. WETTING RAINS ARE LIKELY FOR MANY AREAS AT SOME POINT AS STORMS WILL BE EFFICIENT RAIN PRODUCERS. TEMPERATURES WILL GENERALLY BE IN THE 75 TO 85 DEGREE RANGE FOR LOWER ELEVATIONS. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...HAMMER LONG TERM...SML AVIATION...CLAYCOMB FIRE WEATHER...HAMMER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
335 PM MDT THU AUG 7 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 334 PM MDT THU AUG 7 2014 ...EVENING THUNDERSTORMS...SOME MARGINALLY SEVERE... OBVIOUSLY FROM RADAR AND SATELLITE...A COUPLE OF MAIN AREAS OF CONVECTION THIS AFTERNOON...ONE OVER NORTHEAST COLORADO AND THE OTHER OVER LAS ANIMAS COUNTY. VARIOUS RUNS OF THE HRRR...THE NAM12...AND TO SOME EXTENT...THE GFS40...HAVE HAD THIS CONCEPT. THESE RUNS ALL TAKE THE CONVECTION EASTWARD THROUGH THE EVENING HOURS...IMPACTING NORTHERN AND SOUTHEASTERN PARTS OF THE PLAINS. THE HRRR SHOWS ANOTHER POSSIBLE AREA OF CONVECTION DEVELOPING OVER PUEBLO COUNTY AND TRACKING EAST THROUGH THE EVENING...STARTING AROUND 22Z OR SO. THIS COULD BE THE RESULT OF OUTFLOW COMING SOUTH OUT OF THE NORTHERN CONVECTION INTERACTING WITH OUTFLOW COMING NORTH OUT OF THE SOUTHERN CONVECTION. THERE ARE HINTS THAT SOMETHING LIKE THIS MAY HAPPEN...WITH 2 POSSIBLE OUTFLOWS EMERGING FROM ONGOING CONVECTION...AND INDICATIONS OF LIFT COMING IN FROM THE WEST OVER FREMONT COUNTY. IN ANY EVENT...SHEERS ARE MARGINAL...MAYBE 25-35 KNOTS...BUT ADEQUATE ENOUGH...FOR A FEW MARGINALLY SEVERE STORMS...PRODUCING LIGHTNING...1 INCH HAIL...WIND GUSTS TO 60 MPH AND LOCALLY HEAVY RAIN. BURN SCARS COULD BE IMPACTED WITH FLASH FLOODING IF THEY TAKE A HIT. MOST ACTIVITY SHOULD CLEAR EAST OF THE AREA BY ABOUT 04Z. WATCH IS IN EFFECT FOR THE PLAINS THROUGH 01Z AT THIS POINT. LW TOMORROW...OVERALL...LOOKS QUIETER AT THIS TIME. PROBABLY MORE STABLE WITH LESS OF A TRIGGER...ALTHOUGH IT WILL BE CLOSE. A TRIGGER SEEMS TO EMERGE IN THE MODELS OVER NORTHEAST COLORADO IN THE AFTERNOON. WE WILL HAVE TO SEE IF IT IS FAR ENOUGH SOUTH TO IMPACT CONVECTION DOWN OUR WAY. COULD BE MARGINAL SEVERE THREAT AGAIN IF THAT OCCURS. LW .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 334 PM MDT THU AUG 7 2014 .SATURDAY NIGHT AND SUNDAY...ANOTHER CONVECTIVE COMPLEX COULD DEVELOP SATURDAY AFTERNOON AND EARLY EVENING OVER NORTHEAST COLORADO AND TRACK TOWARDS THE SOUTHEAST. MAINTAINED SCATTERED POPS WELL INTO THE EVENING OVER KIOWA AND NEARBY COUNTIES. ON SUNDAY..CWA WILL BE ON THE SOUTHERN FRINGE OF A SHORTWAVE WHICH PASSES TO THE NORTHEAST. THE DISTURBANCE WILL ALSO BRING IN ANOTHER SURGE FROM THE NORTH...WHICH COULD HELP INCREASE MOISTURE OVER THE EASTERN PLAINS. THE COVERAGE AND STRENGTH OF THE STORMS WILL DEPEND ON SUBTLE FEATURES. HOWEVER...ANTICIPATE WEAK SHEAR SO THREAT FOR WIDESPREAD STRONG TO SEVERE STORMS WILL BE QUITE LOW. GRIDS HAVE MOSTLY SCATTERED STORMS IN THE AFTERNOON...WITH THE GREATER COVERAGE MOVING FURTHER EAST IN THE EVENING. .MONDAY THROUGH THURSDAY...GFS...EC AND ENSEMBLES AGREE ON AMPLIFYING THE RIDGE OVER COLORADO DURING THIS PERIOD. GFS AND EC GENERALLY AGREE THAT THE INITIAL RETURN OF MONSOON MOISTURE WILL MOSTLY BE TO THE WEST OF COLORADO...THEN MOVE EASTWARD INTO COLORADO UNDER THE RIDGE. SURFACE ANTICYCLONES WILL ALSO MOVE SOUTHEAST INTO THE HIGH PLAINS WITH THE NORTHWEST FLOW ALOFT. THE DAY TO DAY VARIATIONS IN THE WEATHER WILL DEPEND ON SUBTLE FEATURES IN THE FLOW. CURRENT THINKING IS THAT THE BEST MONSOON MOISTURE WILL MOSTLY STAY WEST OF THE CWA...AND THAT HIGH PRESSURE ON THE HIGH PLAINS WILL BE TOO FAR EAST TO ADVECT MUCH LOW LEVEL MOISTURE INTO COLORADO. AS A RESULT...THE GRIDS HAVE A MODEST DRYING TREND...WITH NEAR SEASONAL TEMPERATURES. HAVE SOME HIGHER POPS NEAR THE KANSAS BORDER WHICH WILL BE CLOSER TO THE LOW LEVEL MOISTURE. --PGW-- && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 334 PM MDT THU AUG 7 2014 MAINLY VFR CONDITIONS EXPECTED AT TAF SITES THROUGH THE PERIOD. HOWEVER...WILL SEE A PERIOD OF SHOWER AND THUNDERSTORM ACTIVITY THIS EVENING AS A WEATHER DISTURBANCE MOVES ACROSS THE AREA. A FEW STORMS COULD BE MARGINALLY SEVERE...WITH LIGHTNING...1 INCH HAIL...WIND GUSTS TO 60 MPH AND LOCALLY HEAVY RAIN. BEST CHANCES OF STORMS AFFECTING TERMINALS LOOKS TO BE THROUGH 01Z WITH STORMS CONTINUING TO IMPACT THE PLAINS ALONG THE KANSAS BORDER THROUGH ABOUT 04Z. TOMORROW...MORE STORMS POSSIBLE DURING THE AFTERNOON AND EVENING HOURS...BUT LESS WIDESPREAD AND GENERALLY LESS INTENSE THAN TODAY. LW && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...LW LONG TERM...PGW AVIATION...LW
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
103 PM CDT THU AUG 7 2014 .DISCUSSION... 324 AM CDT MAIN FORECAST CONCERNS CONTINUE TO FOCUS ON RAIN POTENTIAL ACROSS MAINLY SOUTHERN PARTS OF THE FORECAST AREA TONIGHT INTO FRIDAY. A FAIRLY VIGOROUS MID-LEVEL SHORT WAVE TROUGH WAS NOTED MOVING INTO THE MISSOURI RIVER VALLEY EARLY THIS MORNING PER GOES WATER VAPOR IMAGERY. IN ADDITION TO A MATURE MCS OVER MISSOURI AND NORTHEAST OKLAHOMA...AN AREA OF ELEVATED CONVECTION WAS OCCURRING IN THE REGION OF WARM ADVECTION MOIST ASCENT ACROSS DOWNSTATE ILLINOIS TO THE NORTH OF THE LOW LEVEL STATIONARY FRONT. ADDITIONAL WEAKER SHOWERS AND THUNDERSTORMS EXTENDED NORTHWEST ALONG THE ELEVATED BAROCLINIC ZONE ACROSS IOWA. MOST OF THIS ACTIVITY IS WELL SOUTH OF SOME OF THE MODEL FORECASTS FROM 24-30 HOURS AGO...AND CURRENT RUNS HAVE LARGELY CONVERGED ON A TREND TO KEEP MOST PRECIP TO THE SOUTHWEST OF THE WFO LOT CWA TODAY...AND ACROSS THE SOUTHERN COUNTIES OF THE CWA TONIGHT INTO FRIDAY. THE WRF-NAM CONTINUES TO DEVELOP SIGNIFICANT PRECIPITATION WELL NORTH OF THE MAIN BAROCLINIC ZONE AND HAS BEEN LARGELY DISCOUNTED IN FAVOR OF A BLEND OF THE GEM/GFS/ECMWF...WHICH KEEP HEAVIEST RAIN JUST SOUTH OF THE CWA ACROSS CENTRAL IL/IN THROUGH THE PERIOD. ADVECTION OF DRY AIR FROM THE EAST AND SOUTHEAST EAST AND SOUTHEAST SUGGESTS A FAIRLY SHARP NORTHERN CUTOFF IN PRECIP/QPF FIELDS...AND HAVE DEPICTED A FAIRLY TIGHT GRADIENT FROM DRY NORTH TO 40-60 PERCENT POPS SOUTH TONIGHT INTO FRIDAY WITH THE GREATEST CHANCES MAINLY SOUTH OF THE ILLINOIS AND KANKAKEE RIVER VALLEYS. DESPITE MARGINAL MID-LEVEL LAPSE RATES LOCALLY HEAVY RAINFALL IS NOT OUT OF THE QUESTION WITH THE STRONGEST 850-700 MB THETA-E ADVECTION AND MOISTURE CONVERGENCE FOCUSED JUST SOUTH OF THE CWA WITH 1.8-2.0" PWATS. SLOWLY DAMPING MID-LEVEL WAVE CONTINUES TO TRACK EAST ACROSS IL/IN FRIDAY...WITH THE POTENTIAL FOR SOME LINGERING LIGHTER RAINFALL ACROSS THE SOUTHERN COUNTIES CLOSER TO THE BAROCLINIC ZONE. WEAK SUBSIDENCE BEHIND DEPARTING/WEAKENING DISTURBANCE ALLOWS WEAK SURFACE HIGH PRESSURE RIDGE TO STRENGTHEN SLIGHTLY ACROSS THE WESTERN LAKES FRIDAY NIGHT/SATURDAY...WITH ONLY WEAK MODEL SIGNALS OF SPOTTY PRECIP POTENTIAL AS WEAK REGION OF MID-LEVEL TROUGHING LINGERS FROM THE DAKOTAS TO THE SOUTHERN LAKES OVER THE WEEKEND. HAVE ELECTED TO MAINTAIN A DRIER FORECAST ALONG THE LINES OF THE 12/00Z ECMWF DURING THE WEEKEND WITH LITTLE SIGNIFICANT FORCING TO KEY ON AND GENERALLY DRY NORTHEASTERLY LOW LEVEL FLOW. LONG RANGE GUIDANCE DEVELOP A MORE AMPLIFIED UPPER TROUGH ACROSS THE MIDWEST MONDAY AND TUESDAY...WHICH SHOULD PRESENT A LITTLE GREATER THREAT OF PRECIP. AGAIN HAVE FAVORED THE WEAKER ECMWF SURFACE EVOLUTION AT THIS DISTANCE...AS OPPOSED TO THE GFS WHICH DEPICTS A DEEPENING SURFACE LOW OVER THE GREAT LAKES. WITH CONTINUED NORTHEAST-EAST SURFACE WINDS THROUGH THE PERIOD... SLIGHTLY COOLER THAN AVERAGE TEMPERATURES EXPECTED WITH MODEST AUGUST LAKE COOLING. HAVE GENERALLY ACCEPTED THE BLENDED BIAS CORRECTED TEMP GUIDANCE WHICH MAINTAINS HIGHS IN THE UPPER 70S/LOW 80S FOR THE MOST PART...WITH SOME MID-UPPER 70S WHERE THICKER CLOUD COVER OR PRECIP IS EXPECTED. MINS GENERALLY 60-65. RATZER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * EASTERLY WINDS 10 KT OR HIGHER WITH MID TEEN GUSTS THROUGH THE AFTERNOON. EXPECT SIMILAR CONDITIONS AGAIN BEGINNING FRIDAY MID MORNING. KMD //DISCUSSION...UPDATED 18Z... EAST-SOUTHEAST WINDS HOLDING FAIRLY STEADY IN THE LOW TEENS WITH OCCASIONAL MID TO UPPER TEENS FOR GUSTS. EXPECT THIS TO CONTINUE THROUGH THE AFTERNOON. AFTER A LULL OVERNIGHT...EXPECT A SIMILAR SCENARIO AGAIN ON FRIDAY AS LOW PRESSURE IN MISSOURI VALLEY TRACKS TOWARDS THE OHIO VALLEY WHILE HIGH PRESSURE REMAINS IN PLACE OVER THE WESTERN GREAT LAKES. HIGH CLOUDS WILL THIN SOME BUT EXPECT AN INCREASE IN MID LEVEL CLOUDS AS THE LOW TRACKS BY TO OUR SOUTH. PRECIPITATION REMAINS CONFINED TO SOUTHERN TIER. KMD //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH FOR WIND SPEED AND DIRECTION KMD //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...VFR. SATURDAY...VFR. SUNDAY...VFR. MONDAY...CHANCE OF TSRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 415 AM CDT WITH HIGH PRESSURE STRETCHED ACROSS THE REGION THIS MORNING...LIGHTER WINDS REMAIN IN PLACE OVER THE LAKE. EXPECT THESE LIGHTER SPEEDS IN THE 10 TO 15 KT RANGE TO CONTINUE TODAY AND MOST OF TONIGHT BEFORE A TREND TOWARDS SLIGHTLY HIGHER SPEEDS OCCURS...PRIMARILY OVER THE SOUTH HALF. A TROUGH OF LOW PRESSURE OVER THE CENTRAL PLAINS WILL SHIFT EAST TOWARDS THE MID MISSISSIPPI VALLEY THROUGH FRIDAY AND FRIDAY NIGHT. THIS WILL HELP SPEEDS INCREASE MORE TOWARDS THE 10 TO 20 KT RANGE LATE TONIGHT INTO FRIDAY MORNING...ONCE AGAIN FOR THE SOUTHERN HALF OF THE LAKE. GUIDANCE STILL VARIES TO THE NORTHERN EXTENT OF THIS LOWS TRACK BUT WITH LATEST TRENDS SUPPORTING A MORE SOUTHERLY TRACK...HELPING TO LIMIT SPEEDS AND ASSOCIATED WAVES FRIDAY AND FRIDAY NIGHT. DESPITE THIS MORE SOUTHERLY TRACK...STILL FEEL THAT A 10 TO 20 KT WIND IS PROBABLE...AND HAVE CONTINUED THIS MENTION IN THE FORECAST. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1223 PM CDT Thu Aug 7 2014 .UPDATE... ISSUED AT 934 AM CDT THU AUG 7 2014 Leading edge of the rain has been having difficulty making it past a Galesburg to Paris line, as some drier dew points around 60 degrees have been in place. Small area of dry weather around Springfield and Jacksonville has been eroding as the next batch of rain spreads in from the southwest. Latest HRRR guidance does not show a lot of northeast progression, and have maintained slight chance PoP`s along the northeast fringes of the forecast area this afternoon. The southwest CWA will see periodic rain through the day, while the southeast sees additional showers moving in after a short late morning break. Precipitable water values of around 1.8 to 1.9 inches will allow for locally heavy rain amounts, and the first batch of rain has already produced around an inch or so in the southwest corner of the CWA in a short time frame. && .SHORT TERM...(Today and tonight) ISSUED AT 251 AM CDT THU AUG 7 2014 Main forecast concern this period will be with the potential for heavy rainfall across west central through southern Illinois. A slow moving upper wave across the Missouri Valley will track across Missouri today and into Illinois by Friday. At the surface, a stalled frontal boundary remains south of our forecast area this morning and is not really expected to move much to the north. As the upper support tracks across Missouri, low pressure will move along the stalled frontal boundary to our south, enhancing the low level convergence along it and focusing the heavy rainfall threat across far west central through southern Illinois today through tonight. Forecast soundings continue to indicate weak instability and shear parameters, but precipitable water values are forecast to be around 2.10 inches which is well above normal, even for August standards in our area. Soundings, no matter what model you look at, indicate moisture content through the entire air column remains very impressive, with locally heavy rains from the slow moving thunderstorms, especially over extreme west central Illinois southeast into south central Illinois. With a persistent low level jet orientated perpendicular into the surface and 850 mb frontal boundary thru tonight, the threat for heavy rainfall is real. Warm cloud depths of over 13,000 feet indicate the thunderstorms will be very efficient rain makers with rainfall rates of 1-2 inches per hour possible wherever stronger storms concentrate. Rainfall totals through tonight will range from 1 to 2 inches along and south of a Rushville to Springfield to Mattoon line, with heavier totals possible near Jacksonville southwest. Areas over west central through southern Illinois can stand some heavy rainfall, at least initially, however, with the high precipitable water values focused along the stalled frontal boundary, flooding potential will remain a concern over our west and southern areas. Further north, big question is when and if rain gets into our northeast and far eastern areas today as high pressure to our north has drawn down some drier air and will effectively keep rain at bay, at least initially for today with only slight chance PoPs. As the upper wave edges across the state later tonight into early Friday, rain chances will increase across the northeast and far eastern counties. && .LONG TERM...(Friday through Wednesday) ISSUED AT 251 AM CDT THU AUG 7 2014 Low pressure will track into the Ohio River Valley on Friday, taking the strongest forcing further east out of the area. Will continue likely PoPs along/east of I-57 during the morning hours, with rain chances diminishing across the board as the day progresses. Models remain in poor agreement this weekend, with the GFS suggesting scattered showers/thunder both Saturday and Sunday as region remains within a band of sheared vorticity aloft. ECMWF is mostly dry, with surface high pressure building southward from the Upper Midwest/Great Lakes and lingering frontal boundary well to the south. Think GFS is being too aggressive with convective development, particularly in the absence of meaningful forcing, so have trended toward the drier ECMWF. As a result, have gone dry for both Saturday and Sunday with highs reaching the lower 80s. After that, a series of weak upper waves will once again dig a significant trough over eastern Canada/Great Lakes by the middle of next week. First wave and associated frontal boundary will swing through Illinois on Monday, accompanied by widely scattered thunder. Second wave will arrive on Tuesday. After that, high pressure will resume control of the weather across central Illinois, allowing a cooler/drier air mass to arrive by next Wednesday. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1222 PM CDT THU AUG 7 2014 Large rain shield slowly working its way eastward this afternoon, but has had trouble penetrating the KPIA-KCMI corridor. Little visibility restriction anticipated in this area during the afternoon. However, heavier showers reducing visibility to 3 or 4 SM around KSPI and soon at KDEC. Large range in ceilings this afternoon, but most likely persistent MVFR conditions expected at KSPI where the rain will be most steady. The rain will become more widely scattered this evening, allowing ceilings to come back up for a time, but have brought them back down again late in the night. Winds to continue from the east-southeast through the period due to slow moving low pressure in Missouri. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEELHART SHORT TERM...SMITH LONG TERM...BARNES AVIATION...GEELHART
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1218 PM CDT THU AUG 7 2014 .SHORT TERM /TODAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 DIFFICULT FORECAST TODAY AS THE MODELS REALLY DO NOT HAVE A GOOD HANDLE ON WHAT IS GOING ON. ALOFT A SHORTWAVE IS SHIFTING ACROSS NORTHERN/CENTRAL MISSOURI. THERE IS GOOD MOISTURE TRANSPORT INTO THIS AREA INTERSECTING A FRONTAL BOUNDARY. HOWEVER THE MOISTURE IS HAVING A TOUGH TIME REACHING IOWA AS IT IS FEEDING THE STORMS IN MISSOURI. AS A RESULT WE HAVE NOT RECEIVED THE HEAVY RAINFALL PREVIOUSLY THOUGHT ACROSS FAR SOUTHERN IOWA THUS THE FLASH FLOOD WATCH WILL BE DROPPED WITH THE MORNING ISSUANCE. AT THE SURFACE...LOW PRESSURE OVER NORTHERN MISSOURI IS TIED TO THE AFOREMENTIONED FRONTAL BOUNDARY AND THIS IS PROGGED TO SLOWLY LIFT TO THE NORTHEAST TODAY. THE QUESTION IS HOW FAR NORTHEAST WILL IT GET. LATEST PROGS BARELY LIFT IT INTO SOUTHEAST IOWA THUS THE HEAVY RAINFALL POTENTIAL SHOULD STAY SOUTH AND EAST OF IOWA WHERE THE BETTER INSTABILITY WILL REMAIN. THERE WILL HOWEVER BE SOME WEAK KINEMATIC FORCING OVER IOWA TODAY THUS THE POTENTIAL FOR SHOWER/ISOLATED THUNDERSTORMS WILL REMAIN OVER MUCH OF THE CWA TODAY UNTIL THE SHORTWAVE AND SURFACE LOW PUSH EAST. AS FOR QPF...THE 06Z NAM WAS BETTER AT WITH ITS QPF FORECAST THAN THE 00Z RUN BUT IT SEEMS TO BE TIED TOO MUCH TO THE FORCING AND THE PAST COUPLE OF NIGHTS THE HEAVIER PRECIP WAS TIED MORE THE TO INSTABILITY AXIS. THE HOPWRF ALSO WAS ALSO PRETTY BULLISH ON PRECIP WHILE THE HRRR...WHICH HAD THE BEST HANDLE ON ONGOING PRECIP...SHOWED THE PRECIP TIED TO THE LOW AND FRONTAL BOUNDARY MAINLY IN MO WITH SCT PRECIP MORE OVER EASTERN IOWA INTO THE EASTERN PORTION OF OUR CWA. I LIKED THE HRRR THE BEST AND PREFER ITS SOLUTION BUT DID BLEND POPS WITH THE HOPWRF AND NEIGHBORING OFFICES. I KEPT THE HIGHEST POPS IN THE SOUTHEAST FROM LATE MORNING INTO THE AFTERNOON WITH CHANCE OR SLIGHT CHANCE POPS ELSEWHERE. NORTHEASTERN IOWA WAS SPARED FROM PRECIP YESTERDAY IN LARGE PART FROM THE HIGH PARKED TO THE NORTHEAST BUT AS THE LOW SHIFTS NORTHEAST THE SURFACE HIGH WILL PUSH EAST AND LOSE MUCH OF ITS INFLUENCE ON NORTHEASTERN PORTIONS OF THE CWA. I DID PUT A PERIOD OF CHANCE POPS IN FOR THE AFTERNOON BUT POP CHANCES SHOULD BE LOWEST IN THIS AREA. PATCHY FOG HAS DEVELOPED OVER MUCH OF THE CWA AND THIS WILL LIKELY HANG AROUND THROUGH A FAIR PART OF THE MORNING. SOUNDINGS ARE SHOWING A PERSISTENT EASTERLY COMPONENT TO THE WIND AND DEEP MOISTURE OVER CENTRAL IOWA THROUGH AT LEAST 15Z. TEMPS WILL ALSO BE COOLER TODAY WITH THE CLOUD COVER AND SCATTERED SHOWERS/STORMS. GENERALLY DROPPED HIGHS ACROSS THE CENTRAL SECTIONS AND KEPT THE NORTHEAST WARMER PRIMARILY DUE TO HIGHER CLOUD HEIGHTS...LOWER PRECIP CHANCES AND QPF. .LONG TERM /TONIGHT THROUGH WEDNESDAY/... ISSUED AT 351 AM CDT THU AUG 7 2014 FORCING WILL PERSIST MAINLY IN THE EAST AND NORTH THIS EVENING WHERE LIGHT SCATTERED SHOWERS MAY LINGER. HOWEVER...THE FORCING WILL SUBSIDE DURING THE NIGHT WITH THE THREAT OF PRECIPITATION DIMINISHING OVERNIGHT. THE STATE WILL CONTINUE TO SEE WESTERLY FLOW ALOFT WITH EASTERLY SURFACE FLOW AS THE SURFACE FRONT REMAINS SOUTH AND WEST OF IOWA AND WEAK RIDGING SLIDING TO THE NORTH. THE RELATIVELY MOIST EASTERLY FLOW WILL LIKELY KEEP A GOOD AMOUNT OF CLOUDINESS AROUND ON FRIDAY INTO SATURDAY. THIS IS EXPECTED TO KEEP DIURNAL RANGES RELATIVELY LOW WITH DAYTIME HIGHS REMAINING BELOW NORMAL WITH LIMITED INSOLATION. DESPITE THE MOIST LOW LEVELS DURING THIS TIME...FORCING WILL BE WEAK OR NON-EXISTENT AND THEREFORE PRECIPITATION IS NOT EXPECTED ON FRIDAY OR SATURDAY. THE NEXT SYSTEM BEGINS TO APPROACH LATE IN THE WEEKEND BUT THE BULK OF FORCING WILL REMAIN TO THE NORTH. THIS WILL LIMIT THUNDERSTORMS CHANCES AND ANY STORMS THAT DO FORM WILL LIKELY BE SOMEWHAT UNORGANIZED AS SHEAR WILL REMAIN WEAK. THE REMAINDER OF THE EXTENDED APPEARS RELATIVELY DRY AFTER MONDAY WITH SOME MODERATION IN TEMPERATURES AS THE EASTERLY FLOW WEAKENS. && .AVIATION...07/18Z ISSUED AT 1218 PM CDT WED AUG 6 2014 LITTLE SIGNIFICANT CHANGE TO CURRENT CONDITIONS EXPECTED UNTIL AFTER SUNRISE ON FRIDAY. LOW-LEVEL MOISTURE AND INVERTED TROF EXTENDING NW FROM SFC LOW IN NRN MO WILL HELP KEEP IFR/LIFR LOW CIGS AND VSBYS AT ALL BUT THE KALO AND KMCW TERMINALS. FOG IS EXPECTED TO DEVELOP OVERNIGHT AS WELL WHICH WILL KEEP VSBYS AND CIGS LOW. CONDS BEGIN TO IMPROVE AFT SUNRISE ON FRIDAY. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...FAB LONG TERM...COGIL AVIATION...ZOGG
AREA FORECAST DISCUSSION
NWS WICHITA KS
326 PM CDT THU AUG 7 2014 .SYNOPSIS... ISSUED AT 323 PM CDT THU AUG 7 2014 A TROUGH IS MOVING ON SHORE TODAY ON THE WESTERN COAST WITH MINOR RIPPLES IN THE FLOW PATTERN THROUGH THE WEEKEND. BOUNDARY POSITIONED OVER WESTERN OKLAHOMA TO EXTREME SOUTH CENTRAL AND SOUTHEAST KANSAS. IT IS EXPECTED TO REMAIN ON ITS SOUTHEAST TRACK THROUGH THE REST OF THE AFTERNOON DIMINISHING THE CHANCES FOR CONVECTION IN THE FORECAST AREA. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 323 PM CDT THU AUG 7 2014 THE MAIN SYSTEMS BOTH THE CURRENT HIGH AND PROGRESSING TROUGH AS MENTIONED ABOVE ARE SITUATED AND EXPECTED TO STAY WELL TO THE NORTH NEAR THE US AND CANADIAN BORDER. THESE RIPPLES ARE OFFSET AND ALMOST DOING THEIR OWN THING. A MESSY PATTERN WITH MULTIPLE DAYS OF CONVECTIVE CHANCES GIVEN A SURFACE FRONTAL BOUNDARY AND REACHING AFTERNOON CONVECTIVE TEMPERATURES. ANOTHER ROUND OF POSSIBLE THUNDERSTORMS IS EXPECTED TONIGHT AFTER DEVELOPMENT IN THE HIGH PLAINS WITH THE CHANCES MAINLY REACHING THE AREA AROUND MIDNIGHT SIMILAR TO THE EVENTS OF LAST EVENING. MODELS SUGGEST THERE MAY BE A WIDER AREA OF EASTWARD MOVING CONVECTION. THE HRRR GIVEN ITS DECENT FORECAST SUCCESS WITH THE ACTIVITY FROM OVERNIGHT...WAS UTILIZED FOR ASSISTANCE IN ATTEMPTING TO DETERMINE TIMING AND LOCATION OF ANY ACTIVITY TONIGHT. WHILE THERE IS HIGHER CONFIDENCE WEST OF THE FORECAST AREA...IT WILL DEPEND ON HOW WELL STUFF WILL HOLD TOGETHER FOR THE INTENSITY AND COVERAGE ESPECIALLY GIVEN LESS SUPPORT AND INSTABILITY THAN LAST NIGHT. BETTER CHANCES OF THUNDERSTORMS APPEAR TO BE ON FRIDAY NIGHT INTO SATURDAY WITH MORE SHEAR AND HIGHER CAPE VALUES ACROSS THE AREA. MINOR ADJUSTMENTS WERE MADE TO THE TEMPERATURES...BUT THE CHANCES OF PRECIPITATION GRIDS WERE ALTERED AND WILL VERY WELL BE TWEAKED WITH EACH FORECAST GIVEN THE ATTEMPTS OF THE MODELS TO GET A HANDLE ON THE EVOLUTION OF CONVECTION ALONG THIS STATIONARY FRONTAL BOUNDARY. JUANITA .LONG TERM...(MONDAY THROUGH THURSDAY) ISSUED AT 323 PM CDT THU AUG 7 2014 A RIDGE IS SET TO RETURN ON MONDAY NIGHT INTO TUESDAY AS THE NEXT TROUGH WILL BE MOVING OVER THE COAST. THIS SYSTEM AND ITS RESPECTIVE FEATURES SHOULD NOT BE MAKING AN IMPACT TO THE EASTERN HALF OF KANSAS UNTIL THE END OF THE FORECAST PERIOD. THEREFORE THE DRY FORECAST WAS MAINTAINED FOR MONDAY NIGHT THROUGH TUESDAY. THE NEXT CHANCE FOR PRECIPITATION WILL BE ON LATE WEDNESDAY NIGHT AND THURSDAY WITH COVERAGE AND LOCATION STILL IN QUESTION DEPENDING ON WHICH MODEL AND RESPECTIVE RUN THAT ONE WOULD LIKE TO CONSIDER. TEMPERATURES ARE GOING TO BE RELATIVELY STAGNANT IN THE UPPER 80S TO LOWER 90S. JUANITA && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1219 PM CDT THU AUG 7 2014 A FRONTAL BOUNDARY EXTENDING FROM SOUTHERN KS TO CENTRAL MO WILL DRIFT SLIGHTLY SOUTH INTO FAR NORTHERN OK BY THIS EVENING WHERE IT IS EXPECTED TO STALL. ANY ISOLATED STORMS THAT DEVELOP ALONG THE FRONT LATE THIS PM/EVE ARE EXPECTED TO REMAIN JUST SOUTH OF ICT AND CNU TERMINALS. MVFR CEILINGS OVER CENTRAL KS ARE EXPECTED TO DISSIPATE AND SCATTER OUT EARLY THIS AFTERNOON. CLUSTERS OF CONVECTION SHOULD FORM OVER THE CENTRAL HIGH PLAINS LATE THIS PM/EVE...MOVING EASTWARD TONIGHT. SOME OF THIS ACTIVITY COULD APPROACH AS FAR EAST AS RSL...BUT HAVE DOUBTS IT WILL MAKE IT MUCH FURTHER EAST...GIVEN MORE LIMITED INSTABILITY. WILL INCLUDE VCTS MENTION AT RSL. IFR CEILINGS LOOK TO DEVELOP ONCE AGAIN OVER NORTHEASTERN KANSAS EARLY FRIDAY MORNING...WHICH COULD IMPACT RSL...SLN...AND CNU. JMC && .PRELIMINARY POINT TEMPS/POPS... WICHITA-KICT 71 89 69 92 / 30 20 40 20 HUTCHINSON 69 87 68 91 / 30 30 40 20 NEWTON 68 87 68 90 / 30 30 40 20 ELDORADO 69 88 68 90 / 30 30 40 30 WINFIELD-KWLD 71 91 70 92 / 20 20 40 30 RUSSELL 68 85 67 89 / 50 30 50 20 GREAT BEND 68 86 67 89 / 50 30 50 20 SALINA 68 87 67 91 / 30 30 40 20 MCPHERSON 68 86 67 90 / 30 30 40 20 COFFEYVILLE 72 90 70 91 / 20 20 30 30 CHANUTE 69 87 68 90 / 20 30 30 30 IOLA 67 86 68 89 / 20 30 30 30 PARSONS-KPPF 70 89 69 91 / 20 30 30 30 && .ICT WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
110 PM EDT Thu Aug 7 2014 ...Updated Aviation Discussion... ...Forecast Update... Issued at 855 AM EDT Thu Aug 7 2014 Quick update to the forecast this morning to account for the latest trends. As expected, the band of showers over southern IN has weakened over the past hour or so and should continue to do so through the remainder of the morning hours. Therefore, have trimmed pops back a bit for the rest of the morning hours. Also brought the forecast more in line with current obs. Issued at 640 AM EDT Thu Aug 7 2014 Continue to see rain showers north of a frontal boundary, stretching from central Illinois southeast to KOWB and with very light showers continuing southeast into our forecast area. Latest HRRR insists that these showers will dissipate over the next hour or two. Have a couple of areas of focus for additional development late this morning and through the afternoon hours. One will be north of the current band`s axis and the other will be over western KY. Still a question if lightning will occur with the cells near Louisville. Forecast soundings show the best instability above 700 mb, so any cells that develop would be elevated. Cannot rule out one or two strikes, so have put in isolated storms for the afternoon. Still think the more strikes will occur with storms that develop in the more unstable airmass over our southwest forecast area. .SHORT TERM (Now through Friday)... Issued at 315 AM EDT Thu Aug 7 2014 Early this morning a frontal boundary lies over the TN Valley. Some weak lift north of this front is resulting in a thin line of scattered showers from roughly KSTL TO KOWB. The GFS has this thin band bringing shower chances into the Louisville Metro throughout the day. Will go more optimistic than that as we should see a narrow ridge aloft stabilizing the atmosphere by this afternoon. As for the rest of the forecast area, still looks like the best chance for thunderstorms will reside west of the I-65 corridor and closer to the front to our south. This front will start lifting north as a warm front late tonight. Combine that surface forcing with an upper disturbance, now over Missouri, closer to the region as well as increasing precipitable waters should make for better rain chances late Thursday night. Storms look likely areawide for Friday as the warm front stalls somewhere over southern Indiana and low pressure rides up the lower Ohio Valley. Rainfall totals through Friday should average around an inch, with the highest amounts in our far western forecast area. .LONG TERM (Friday Night through Wednesday)... Issued at 315 AM EDT Thu Aug 7 2014 Friday Night - Saturday... Wet conditions look to continue Friday night and Saturday as a weak area of low pressure slowly moves across the Ohio Valley, interacting with a moist airmass. Will continue mention of scattered to numerous showers during these two periods. Best focus looks to be across the northern two-thirds of the CWA Friday night, and across the southeastern half on Saturday, although everyone has a pretty decent shot at getting in on the action. PWATs look to still be around or just below 2 inches through the column so expect the main threat with any shower or storm to be heavy rain. Cloud to ground lightning will also be a main concern for outdoor activities. Expect mild overnight lows on Friday night in the upper 60s in low 70s. Highs on Saturday will be dependent on convection, but low and mid 80s look reasonable. Saturday Night - Sunday Night... Shallow and weak NW flow aloft will remain in control of the area as we end the weekend, meanwhile a weak surface low will meander slowly just east of the area. This will keep the focus for shower and storm activity mainly east of I-65, although cannot rule out an isolated shower over the CWA on Saturday night and Sunday. Coverage, mainly showers, should be isolated to widely scattered at best over the Bluegrass during this time. Look for lows each night mainly in the upper 60s. A nice temperature gradient looks to set up for highs on Sunday with upper 80s SW to around 80 in our NE. Monday - Wednesday... An upper ridge will build more solidly over the western and central CONUS Monday through Wednesday. Meanwhile, an impulse will dive across the Great Lakes and combine with the weak low pressure just to our NE, helping to amplify a trough over the eastern CONUS. The Ohio Valley will find itself in the increasing NW flow aloft between these two features for the first half of next week. This will leave us in a drier overall pattern, however will likely have to deal with more diurnally driven convection, and/or any convection that may fire in response to passing waves embedded in the flow. Have depicted the best chances for isolated to scattered storm chances across our SE half of the CWA, with a drier atmosphere anticipated over our NW closer to a surface high. Model data supports a warm up in temperatures for the first half of the week, especially Tuesday and Wednesday. Have nudged the forecast closer to the upper 80s and low 90s for the SW half of the forecast area closer to the upper ridge. Being careful to not get too aggressive as some of the rainfall advertised leading up to this time period, could limit our heating efficiency just a bit. && .AVIATION (18Z TAF Update)... Issued at 107 PM EDT Thu Aug 7 2014 VFR conditions will persist through this afternoon into this evening, before some deteriorating conditions approach early Friday morning through the rest of the TAF period. For the remainder of this afternoon, generally dry conditions should prevail. There is a chance of a stray shower or storm near KBWG, thus will continue with a brief period of VCTS mention there. Otherwise, expect some diurnal cu along with increasing mid and high clouds. Showers and a few embedded storms will increase in coverage tonight as deep moisture pushes into the region. Have tried to time the best coverage of precip into terminals with -SHRA wording. There may be some thunderstorms as well, but confidence is not high enough in storm coverage to include VCTS wording. Conditions could drop to MVFR in the heavier showers, but should generally remain VFR outside of any precip. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD/RJS Short Term.....RJS Long Term......BJS Aviation.......KJD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
250 PM EDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM EDT THU AUG 7 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG AXIS EXTENDING FM MN INTO NW ONTARIO...WITH SFC HI PRES ELONGATED FM JAMES BAY INTO FAR WRN LK SUP. VERY DRY/STABLE MID LVLS SHOWN ON THE LOCAL 00Z RAOBS AND THE LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE RDG HAVE RESULTED ARE BRINGING MOCLR SKIES TO THE CWA. WITH LGT WINDS UNDER THE MOCLR SKIES...SOME PATCHY FOG HAS FORMED. THERE IS A SHRTWV JUST E OF LK WINNIPEG THAT IS LIFTING SLOWLY NEWD...AND THERE ARE SOME BKN MID/HI CLDS OVER NW MN AND FAR NW ONTARIO. TEMPS/RH/FIRE WX PARAMETERS ARE THE MAIN FCST CONCERNS IN THE SHORT TERM AS UPR RDG/SFC HI PRES ARE FCST TO DOMINATE THRU TNGT. TODAY...SFC HI PRES IS FCST TO CENTER OVER THE E HALF OF LK SUP AS UPR RDG SHIFTS TO AN AXIS FM UPR MI TO JAMES BAY. EXCEPT FOR SOME SCT CU ALONG AND INLAND FM LK BREEZE BNDRYS THAT DVLP UNDER THE RATHER FLAT PRES GRADIENT AS WELL AS SOME PATCHY HI CLDS WELL TO THE S OF SHRTWV LIFTING NEWD THRU ONTARIO...THE DAY WL FEATURE PLENTY OF SUNSHINE. WITH H85 TEMPS FCST TO PEAK AT 13-14C OVER THE W THIS AFTN...SIMILAR TO YDAY...EXPECT MAX TEMPS RISING INTO THE 70S/LO 80S AWAY FM THE LK MODERATION...WHICH WL BE ENHANCED NEAR THE BAY OF GREEN BAY AND ALONG LK SUP E OF THE KEWEENAW IN THE E H925 FLOW. SFC DEWPTS SHOULD MIX OUT AS LO AS THE UPR 40S THIS AFTN...RESULTING IN MIN RH DOWN TO 30-35 PCT AWAY FM LK MODERATION. DESPITE RECENT DRYNESS AT MANY LOCATIONS...LIGHT WINDS WL MITIGATE THE FIRE WX THREAT. TNGT...WITH SFC HI PRES REMAINING OVER THE E HALF OF LK SUP...EXPECT DRY WX. ALTHOUGH MID LVL DRY AIR WL REMAIN IN PLACE...SOME HI CLDS MAY DRIFT THRU THE UPR LKS ON THE SRN FLANK OF SHRTWV LIFTING TOWARD JAMES BAY. TEMPS OVER THE INTERIOR SHOULD STILL BOTTOM OUT IN THE 40S...COOLEST OVER THE INTERIOR E CLOSER TO THE HI AND LIGHTER H925 WINDS. ADDED SOME PATCHY FOG OVER THE INTERIOR CENTRAL AND E...WHERE EXPECTED MIN TEMPS ARE LIKELY TO FALL AOB CROSS OVER DEWPTS THIS AFTN. A BIT STRONGER S WIND AT H925 WL LIMIT THE DIURNAL FALL OVER THE W. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 249 PM EDT THU AUG 7 2014 SFC HIGH PRESSURE REMAINS IN CONTROL OF THE WEATHER THROUGH THIS FORECAST PERIOD WITH QUIET WEATHER CONTINUING. PERSISTENCE IS THE WAY TO GO WITH THIS FORECAST AND WILL NOT MAKE VERY MANY CHANGES TO THE GOING FORECAST. IN THE EXTENDED...GFS AND ECMWF SHOW A 500 MB TROUGH OVER THE UPPER GREAT LAKES 12Z MON WITH A SFC COLD FRONT MOVING THROUGH THE AREA. THIS TROUGH HEADS SOUTHEAST 12Z TUE WITH A COLD FRONT SOUTH AND EAST OF THE AREA. AN UPPER LEVEL RIDGE MOVES INTO THE ROCKIES 12Z TUE. SFC HIGH PRESSURE MOVES INTO THE UPPER GREAT LAKES 12Z WED WHICH REMAINS OVER THE AREA INTO THU. TEMPERATURES LOOK TO STAY NEAR NORMAL THIS FORECAST PERIOD WITH LOW CHANCE POPS MON INTO TUE AND THEN DRY TUE NIGHT THROUGH THU. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 138 PM EDT THU AUG 7 2014 EXPECT VFR CONDITIONS THIS FORECAST PERIOD AT ALL 3 TAF SITES WITH DRY HIGH PRESSURE DOMINATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 AM EDT THU AUG 7 2014 HI PRES WILL DOMINATE THE UPPER GREAT LAKES THROUGH THIS WEEKEND... WITH LIGHT WINDS BELOW 15 KTS AND WAVES GENERALLY LESS THAN 2 FT. AFTER THE HI FINALLY MOVES OFF TO THE E...A COLD FRONT WILL CROSS LAKE SUPERIOR ON MON. N WINDS MAY INCREASE UP TO 20 KTS FOLLOWING THIS FRONTAL PASSAGE AND IN ADVANCE OF THE NEXT HI PRES BUILDING OVER ONTARIO. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...07 AVIATION...TITUS MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
139 PM EDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM EDT THU AUG 7 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW UPR RDG AXIS EXTENDING FM MN INTO NW ONTARIO...WITH SFC HI PRES ELONGATED FM JAMES BAY INTO FAR WRN LK SUP. VERY DRY/STABLE MID LVLS SHOWN ON THE LOCAL 00Z RAOBS AND THE LARGE SCALE SUBSIDENCE ASSOCIATED WITH THE RDG HAVE RESULTED ARE BRINGING MOCLR SKIES TO THE CWA. WITH LGT WINDS UNDER THE MOCLR SKIES...SOME PATCHY FOG HAS FORMED. THERE IS A SHRTWV JUST E OF LK WINNIPEG THAT IS LIFTING SLOWLY NEWD...AND THERE ARE SOME BKN MID/HI CLDS OVER NW MN AND FAR NW ONTARIO. TEMPS/RH/FIRE WX PARAMETERS ARE THE MAIN FCST CONCERNS IN THE SHORT TERM AS UPR RDG/SFC HI PRES ARE FCST TO DOMINATE THRU TNGT. TODAY...SFC HI PRES IS FCST TO CENTER OVER THE E HALF OF LK SUP AS UPR RDG SHIFTS TO AN AXIS FM UPR MI TO JAMES BAY. EXCEPT FOR SOME SCT CU ALONG AND INLAND FM LK BREEZE BNDRYS THAT DVLP UNDER THE RATHER FLAT PRES GRADIENT AS WELL AS SOME PATCHY HI CLDS WELL TO THE S OF SHRTWV LIFTING NEWD THRU ONTARIO...THE DAY WL FEATURE PLENTY OF SUNSHINE. WITH H85 TEMPS FCST TO PEAK AT 13-14C OVER THE W THIS AFTN...SIMILAR TO YDAY...EXPECT MAX TEMPS RISING INTO THE 70S/LO 80S AWAY FM THE LK MODERATION...WHICH WL BE ENHANCED NEAR THE BAY OF GREEN BAY AND ALONG LK SUP E OF THE KEWEENAW IN THE E H925 FLOW. SFC DEWPTS SHOULD MIX OUT AS LO AS THE UPR 40S THIS AFTN...RESULTING IN MIN RH DOWN TO 30-35 PCT AWAY FM LK MODERATION. DESPITE RECENT DRYNESS AT MANY LOCATIONS...LIGHT WINDS WL MITIGATE THE FIRE WX THREAT. TNGT...WITH SFC HI PRES REMAINING OVER THE E HALF OF LK SUP...EXPECT DRY WX. ALTHOUGH MID LVL DRY AIR WL REMAIN IN PLACE...SOME HI CLDS MAY DRIFT THRU THE UPR LKS ON THE SRN FLANK OF SHRTWV LIFTING TOWARD JAMES BAY. TEMPS OVER THE INTERIOR SHOULD STILL BOTTOM OUT IN THE 40S...COOLEST OVER THE INTERIOR E CLOSER TO THE HI AND LIGHTER H925 WINDS. ADDED SOME PATCHY FOG OVER THE INTERIOR CENTRAL AND E...WHERE EXPECTED MIN TEMPS ARE LIKELY TO FALL AOB CROSS OVER DEWPTS THIS AFTN. A BIT STRONGER S WIND AT H925 WL LIMIT THE DIURNAL FALL OVER THE W. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 345 AM EDT THU AUG 7 2014 MAIN ISSUES DURING THE LONG TERM WILL BE CONTINUED DRY WEATHER THROUGH THE WEEKEND WITH THE NEXT CHANCE OF RAIN PUSHING IN AHEAD OF A COLD FRONT FOR THE FIRST PART OF THE WORKWEEK. FRIDAY THROUGH SATURDAY...BROAD SURFACE RIDGING ALONG WITH UPPER LEVEL 500MB RIDGING WILL REMAIN IN PLACE ACROSS MUCH OF THE UPPER GREAT LAKES REGION THROUGH AS WELL AS MUCH OF THE EASTERN CONUS THROUGH THIS TIME FRAME. DRY WEATHER WILL BE THE RULE UNDER THE RIDGE AS MOISTURE ADVECTION WILL BE LIMITED WITH VERY LOW DEEP LAYER 1000-500MB RH VALUES. THE SURFACE HIGH WILL SLOWLY SHIFT TO THE EAST DURING THE DAY SATURDAY. THIS WILL KEEP LIGHT WINDS IN THE FORECAST WITH THE STRONGEST GUSTS EXPECTED TO BE ALONG LAKE BREEZE BOUNDARIES DURING THE AFTERNOON HOURS. CONDITIONS ARE BECOMING VERY DRY ACROSS MUCH OF THE U.P. AS THERE HAS BEEN VERY MINIMAL PRECIPITATION OVER THE PAST COUPLE WEEKS. THIS HAS ALLOWED BOTH SOIL AND VEGETATION TO BECOME DRY. DECENT MIXING CONDITIONS ARE EXPECTED TO OCCUR EACH AFTERNOON THROUGH THIS TIME PERIOD...WHICH WILL LEAD TO INCREASED FIRE DANGER...FORTUNATELY...WINDS WILL CONTINUE TO BE FAIRLY LIGHT AS PREVIOUSLY MENTIONED. HAVE KEPT LOWER AFTERNOON DEWPOINTS IN PLACE AS DRIER AIR ALOFT MIXES DOWN TO THE SURFACE WITH AFTERNOON HEATING. TEMPERATURES WILL CONTINUE TO WARM THROUGH THIS PERIOD WITH 850MB TEMPS WARMING FROM NEAR 13C THURSDAY AFTERNOON TO AROUND 14C BY SATURDAY AFTERNOON AS THE HIGH CONTINUES THE SLOW TREK EASTWARD. SATURDAY NIGHT THROUGH THE REMAINING EXTENDED...THE NEXT UPPER LEVEL TROUGH AND DEVELOPING SURFACE LOW ARE PROGGED TO BE NEAR THE JUST NORTH OF LAKE WINNIPEG SATURDAY NIGHT WITH A COLD FRONT STRETCHING SOUTHWESTWARD ACROSS THE DAKOTAS AS SHOWN BY ANALYZING 850 THETA E ALONG WITH SURFACE WINDS. THIS WILL BE THE MAIN FOCUS FOR SHOWER AND THUNDERSTORM ACTIVITY. THE LOW WILL SHIFT EASTWARD TO NORTHERN QUEBEC BY MONDAY AFTERNOON AS THE FRONT DRAPES ACROSS THE UPPER GREAT LAKES REGION. RIGHT NOW THE BEST CHANCE OF SHOWER AND THUNDERSTORM ACTIVITY WOULD BE LATE SUNDAY NIGHT OVER WESTERN UPPER MI AND DURING THE DAY MONDAY ACROSS MOST OF UPPER MI. DEEP LAYER FORCING SHOULD BE PLENTIFUL ALONG THE FRONT TO ALLOW PRECIPITATION TO DEVELOP ACROSS THE AREA AS SHOWN BY OVERLAYING QCONV ALONG WITH 1000-500MB RH. THIS WILL ALSO BE AROUND THE SAME TIME THAT THE UPPER LEVEL 500MB TROUGH AXIS SWINGS ACROSS THE AREA HELPING TO KEEP INSTABILITY HIGH ENOUGH FOR CONTINUED THUNDERSTORM CHANCES. MOISTURE WILL NOT BE OVERLY ABUNDANT THEREFORE WILL KEEP THE BEST CHANCE POPS RIGHT ALONG AND JUST AHEAD OF THE FRONT ALONG THE FAIRLY NARROW RIBBON OF MOISTURE. THE FRONT IS PROGGED TO BE EAST OF THE AREA BY TUESDAY...HOWEVER...UPPER LEVEL TROUGHING AND LINGERING MOISTURE NEARBY...WOULD EXPECT SHOWERS TO LINGER THROUGH AT LEAST TUESDAY MORNING. DRY HIGH PRESSURE WILL BUILD IN AT THE SURFACE TUESDAY NIGHT AND LINGER THROUGH WEDNESDAY AS UPPER LEVEL 500MB HEIGHT RISES BEGIN TO PUSH BACK INTO THE UPPER PENINSULA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 138 PM EDT THU AUG 7 2014 EXPECT VFR CONDITIONS THIS FORECAST PERIOD AT ALL 3 TAF SITES WITH DRY HIGH PRESSURE DOMINATING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 345 AM EDT THU AUG 7 2014 HI PRES WILL DOMINATE THE UPPER GREAT LAKES THROUGH THIS WEEKEND... WITH LIGHT WINDS BELOW 15 KTS AND WAVES GENERALLY LESS THAN 2 FT. AFTER THE HI FINALLY MOVES OFF TO THE E...A COLD FRONT WILL CROSS LAKE SUPERIOR ON MON. N WINDS MAY INCREASE UP TO 20 KTS FOLLOWING THIS FRONTAL PASSAGE AND IN ADVANCE OF THE NEXT HI PRES BUILDING OVER ONTARIO. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KEC AVIATION...TITUS MARINE...KC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
320 PM CDT THU AUG 7 2014 .SHORT TERM...(TONIGHT THROUGH SUNDAY) ISSUED AT 320 PM CDT THU AUG 7 2014 SOMEWHAT OF A MESSY FORECAST THE NEXT FEW DAYS. TIMING BEST PCPN CHANCES AND PCPN AMOUNTS SHOULD BE THE MAIN FORECAST CHALLENGES. WATER VAPOR SATELLITE LOOP EARLY THIS AFTERNOON SHOWED THE FOLLOWING. A CLOSED LOW WAS NEAR THE MO/IL BORDER BUT MOVING OFF TO THE SOUTHEAST. UPSTREAM...LOW PRESSURE ALOFT CENTERED AROUND 500 MB WAS OVER NRN UT. SEVERAL PIECES OF SHORTWAVE ENERGY WERE NOTED FROM UT INTO WY AND CO. AT THE SURFACE...A WEAK INVERTED TROUGH/CONVERGENCE ZONE WAS NOTED OVER WRN IA. KOAX SOUNDING FROM 12Z SHOWED ABOUT 1.80 INCHES OF PRECIPITABLE WATER AND A NEARLY SATURATED AIRMASS BELOW 700 MB. LATEST RUNS OF THE HRRR MODEL...WHICH DID NOT DO A PERFECT JOB LAST EVENING...BUT WAS FAIRLY GOOD...SHOWS SPOTTY SHOWERS WILL STILL BE POSSIBLE IN OUR AREA AT LEAST THROUGH THE EVENING. AS THE NIGHT GOES ON...A WEAK SURFACE RIDGE SHOULD TEND TO BUILD IN AND FORECAST SOUNDINGS SHOW THE 850 TO 500 MB LAYER DRYING A BIT. THERE COULD BE SOME PATCHY FOG...SO ADDED THAT. THE SPOTTY SHOWERS HAVE BEEN VERY EFFICIENT THE PAST 24 HOURS...AND THIS WILL PROBABLY CONTINUE THIS EVENING. LOOK FOR LOWS MAINLY FROM 63 TO 66. SOME LIGHT PCPN COULD ALSO MOVE IN FROM THE WEST LATE TONIGHT...BUT CHANCES APPEAR BETTER FRIDAY AS LARGE SCALE LIFT DEVELOPS AND SURFACE RIDGING WEAKENS. CLOUDS AND PCPN SHOULD HOLD HIGHS DOWN TO MAINLY THE 75 TO 80 DEGREE RANGE. THE CHANCE FOR SHOWERS AND TSTMS CONTINUES OVER THE WEEKEND. THE BEST PROBABILITIES SHOULD BE LATE SATURDAY NIGHT AND SUNDAY. BOTH THE 12Z GFS AND 12Z ECMWF SHOW RAIN AMOUNTS OVER HALF AN INCH. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 320 PM CDT THU AUG 7 2014 KEPT A CHANCE OF THUNDERSTORMS IN FOR SUNDAY NIGHT AND MONDAY... THEN WENT MAINLY DRY MONDAY NIGHT THROUGH WEDNESDAY. LOOKS LIKE IT TURNS WET TOWARD DAY 7 WITH SHORTWAVE ENERGY DROPPING IN FROM THE NORTHWEST AND LIFTED INDICES DROP. HIGHS SHOULD BE MOSTLY IN THE 80S AND LOWS 60 TO 65. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1239 PM CDT THU AUG 7 2014 MVFR/IFR CONDITIONS TO CONTINUE THROUGH THE TAF PERIOD WITH VARIABLE SKY AND VSBYS. MAY NEED TO ADD SOME LIFR CONDITIONS OVERNIGHT.MOIST CONDITIONS REMAIN IN PLACE...BUT COULD SEE SOME IMPROVEMENT WESTERN AREAS WITH SLIGHTLY DRIER CONDITIONS TOWARD KOFK. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...ZAPOTOCNY
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1252 PM CDT THU AUG 7 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CDT THU AUG 7 2014 THE MODELS SHOW MOISTURE POOLING ACROSS SWRN NEB EARLY THIS EVENING WITH PRECIPITABLE WATER INCREASING TO AROUND 1.5 INCHES. ITS A LIKELY POP SITUATION AS THE H500MB RIDGE FLATTENS AND A DISTURBANCE ACROSS SWRN WY MOVES EAST SOUTHEAST THROUGH SWRN NEB TONIGHT. THE FCST DELAYS POPS BY 3 HOURS GIVEN THE BIAS IN MODEL TIMING WHICH BRINGS THE BEST RAIN CHANCES THIS EVENING AND OVERNIGHT WHICH IS MORE IN LINE WITH THE QPF FORECAST. HPC CARRIES THE BEST QPF MORE SOUTH THRU SWRN NEB THEN WRN KANSAS BUT THE RAP AND NAM CORFIDI VECTORS FOR A FORWARD PROPAGATING MCS SHOW EASTWARD MOTION WHICH SUPPORTS THE BLENDED QPF FORECAST WE HAVE PREPARED. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 357 AM CDT THU AUG 7 2014 MODELS ARE IN BETTER AGREEMENT IN THE EXTENDED THAN PREVIOUS RUNS WITH THE OVERALL PATTERN. SOUTHERN UPPER LEVEL RIDGE ON FRIDAY WILL BUILD NORTHWEST ACROSS THE ROCKIES OVER THE WEEKEND AS A LOW MOVES ACROSS TOWARDS CENTRAL CAL AND A TROUGH DIGS ACROSS THE GREAT LAKES. MODELS STALL THE CLOSED LOW ACROSS WESTERN CAL WITH THE RIDGE CONTINUING TO BUILD TOWARDS MONTANA BY TUESDAY. THE WESTERN LOW THEN LIFTS NORTH AND BEGINS TO FLATTEN THE RIDGE. PERIODIC CHANCES FOR RAIN PERSIST THROUGH MUCH OF THE FORECAST. OVER THE WEEKEND SEVERAL DISTURBANCES WILL RIDE NORTH OF THE RIDGE. TIMING OF THE WAVES VARIES BETWEEN THE MODELS AND FORECAST WILL RETAIN LOW CHANCE POPS THROUGH THE WEEKEND. WHILE POPS ARE IN NEARLY EVERY PERIOD OVER THE WEEKEND...NOT EXPECTING IT TO BE A WASH OF A WEEKEND. DEVELOPMENT ACROSS THE FRONT RANGE WITH ACTIVITY SLIDING EAST/SOUTHEAST ACROSS THE CWA. THERE WILL ALSO BE SOME ISOLATED LATE DAY ACTIVITY DUE TO A WEAKENING CAP DUE TO PLENTIFUL BL MOISTURE. THE RICH BL MOISTURE WILL ALSO NEED TO BE MONITORED FOR LATE NIGHT/MORNING PATCHY FOG. TEMPS OVER THE WEEKEND WILL BE SEASONALLY COOL /LOWER TO MID 80S/ DURING THE DAY AND MILD OVERNIGHT /LOWER TO MID 60S. AS WE START THE WORK WEEK...FLOW BECOMES M0RE NORTHWESTERLY. MODELS CONTINUE A TRAIN OF SHORT WAVES AROUND THE RIDGE...HOWEVER THEY BECOME SPACED OUT MORE. STILL GOING TO SEE OCCASIONAL POPS WITH EACH WAVE...AND TIMING IS HIGHLY UNCERTAIN THIS FAR OUT. WITH THE RIDGE BUILDING TO THE WEST...TEMPS SHOULD CLIMB A LITTLE. GUIDANCE IS IN THE MID AND UPPER 80S...WHICH IS CLOSER TO SEASONAL NORMS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1252 PM CDT THU AUG 7 2014 DETERIORATING FLIGHT CONDITIONS ANTICIPATED FOR ALL AREA TERMINALS THIS EVENING AND OVERNIGHT AS A UPPER LEVEL WAVE SPARKS OFF CONVECTION ACROSS THE HIGH PLAINS. SKIES ARE CLEARING THIS AFTERNOON OVER MUCH OF THE REGION...AND WITH FURTHER HEATING...INSTABILITY WILL BE ON THE INCREASE...PROVIDING FOR THE POTENTIAL OF A STRONG STORM OR TWO THIS EVENING. THE GREATEST RISK OF A STRONG OR SEVERE TSTORM WILL BE ACROSS THE CENTRAL SANDHILLS AND POINTS SOUTH AND WEST WHERE WET MICROBURSTS WOULD BE THE MAIN CONCERN...HOWEVER LARGE HAIL CANNOT BE RULED OUT AT THIS TIME. LATE THIS EVENING THE SEVERE THREAT WILL DECREASE...BUT THE HEAVY RAIN POTENTIAL WILL INCREASE...WITH POSSIBLE VISIBILITY RESTRICTIONS FOR OUR SOUTHWESTERN NEBRASKA TERMINALS. AS THE STORMS MOVE OFF TO THE SOUTHEAST...ENOUGH RESIDUAL LOWER TROPOSPHERIC MOISTURE WILL PROVIDE FOR STRATUS AND/OR FOG. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...JACOBS
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
649 PM EDT THU AUG 7 2014 .SYNOPSIS... A COLD FRONT WILL SHIFT SOUTH OF THE REGION THROUGH TONIGHT AND WILL STALL ON FRIDAY. THIS FRONT WILL SLOWLY LIFT NORTHWARD OVER THE AREA THIS WEEKEND THROUGH EARLY NEXT WEEK...BRINGING RENEWED CHANCES OF SHOWERS AND THUNDERSTORMS EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 PM THURSDAY...THE COLD FRONT WAS LOCATED ALONG A LINE FROM NEAR ELIZABETHTOWN THROUGH MARION TO JUST NORTH OF KINGSTREE. THE FRONT IS EXPECTED TO CONTINUE TO SLOWLY DRIFT SOUTH AND EAST THROUGH THE EVENING BEFORE STALLING AT THE COAST. LATEST RADAR IS SHOWING CONVECTION IN SOUTHERN PENDER COUNTY. ALSO...A FEW SHOWERS ARE STRUGGLING TO DEVELOP ALONG WEAK BOUNDARIES SEEN IN THE HIGH RESOLUTION RADAR DATA. WE CAN EVEN SEE A WEAK LAKE BREEZE BOUNDARY NORTH OF LAKE WACCAMAW BUT WITH THIS WEAK LOW LEVEL FORCING THE CONVECTION TO THE SOUTH IS STRUGGLING. THIS MAY BE THE HIGH LCL VALUES AND THE STORMS ARE NEEDING A BIT MORE LIFT THAN WHAT IS AVAILABLE AT THIS TIME. THE LATEST HRRR RUNS ARE SHOW CONVECTION A BIT MORE WIDESPREAD AND GENERALLY THE EAST OF THE FRONT. THE INSTABILITIES ARE RUNNING AROUND 2000 TO 2500 JOULES PER KILOGRAM TO THE EAST OF THE FRONT BUT THERE IS ABSOLUTE NO CONVERGENCE AT THE SURFACE WITH LIGHT WINDS. THE OTHER FORCING IN THE AREA OF CONCERN IS THE SEA BREEZE WHICH IS PINNED CLOSE TO THE COAST. THE HRRR IS NOT BULLISH ON CONVECTION ON THE SEA BREEZE BOUNDARY. SO HAVE A GONE WITH THE BEST CHANCES OF CONVECTION OVER THE EXTREME NORTHERN TIER OF COUNTIES CLOSER TO THE ONGOING CONVECTION AND A TAILING BAND OF ISOLATED CONVECTION ALONG THE COAST TO THE EAST OF THE FRONT. WITH THE FRONTAL BOUNDARY STALLING ALONG THE COAST...WE WILL CONTINUE WITH AN ISOLATED CHANCE OF SHOWERS OR A THUNDERSTORM ON THE EAST SIDE OF THE FRONT OVERNIGHT...BUT CONFIDENCE ON CONVECTION IS NOT THAT HIGH. TEMPERATURES OVERNIGHT ARE EXPECTED TO FALL INTO THE MIDDLE 70S ALONG THE COAST TO THE UPPER 60S TO NEAR 70 NORTH AND WEST OF INTERSTATES 20 AND 95. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 330 PM THURSDAY...A COLD FRONT WILL BE STALLED JUST SOUTH OF THE FORECAST AREA AT THE START OF THE PERIOD. FORECAST SOUNDINGS SHOW PLENTY OF DRY AIR IN THE MID LEVELS FRI MORNING...BUT THE COLUMN MOISTENS DURING THE DAY FROM WEST TO EAST. THE FRONT WILL GRADUALLY LIFT BACK NORTHWARD AS A WARM FRONT LATE FRI/EARLY SAT. THOUGH THE BEST ISENTROPIC ASCENT WILL REMAIN TO OUR WEST DURING FRI...WILL ADVERTISE SLIGHT TO CHC POPS ACROSS OUR FAR INLAND ZONES AS DEEPER MOISTURE SPREADS ACROSS THE CENTRAL CAROLINAS. POPS WILL REMAIN LOWER ALONG THE COAST DURING THE DAY FRI... GRADUALLY INCREASING OVERNIGHT INTO SAT MORNING. BY 12Z SAT THE WARM FRONT WILL BE DRAPED ACROSS OUR CWA...BRINGING AN EXTENDED PERIOD OF ABOVE NORMAL PCPN CHANCES AREA-WIDE. PWATS SURGE ABOVE 2.0 INCHES ON SAT AS SOUTHERLY LOW-LEVEL FLOW INCREASES BEHIND THE WARM FRONT. SHOWER COVERAGE IS EXPECTED TO BECOME MORE WIDESPREAD SAT AFTN AND THROUGH THE OVERNIGHT HOURS AS UPPER IMPULSES ALLOW WAVES OF LOW PRESSURE TO DEVELOP ALONG THE FRONT. GIVEN THE ANTECEDENT RAINFALL AND WEAK STEERING FLOW OF 5-10 KT AT BEST...LOCALLY HEAVY RAINFALL COULD RESULT IN MINOR FLOODING CONCERNS TOWARD THE END OF THE PERIOD. HIGH TEMPS ON FRIDAY WILL GENERALLY BE IN THE MID TO UPPER 80S... WITH LOWS DROPPING INTO THE LOWER 70S. HAVE SIDED WITH THE COOLER MET NUMBERS ON SATURDAY GIVEN THE EXPECTED CLOUD COVER AND INCREASED SHOWER COVERAGE DURING THE DAY. THIS YIELDED HIGHS IN THE MID 80S ACROSS THE AREA. && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 330 PM THURSDAY...LONGWAVE PATTERN TO MODIFY ACROSS THE CAROLINAS SUNDAY THRU TUESDAY WITH A LESS AMPLIFIED LONGWAVE TROF PERSISTING ACROSS THE CAROLINAS. AT THE SAME...A PROGRESSIVE S/W RIDGE TO BYPASS THE FA TO OUR NORTH...PUSHING ACROSS THE GREAT LAKES TO THE NE STATES DURING THIS TIME PERIOD. UNFORTUNATELY FOR THE ILM CWA...A MEANDERING FRONTAL BOUNDARY ACROSS THE CAROLINAS WILL GET LEFT BEHIND THRU TUESDAY AS IT BECOMES ORIENTED PARALLEL WITH THE UPPER FLOW. THE FORCING ALONG THIS FRONT WILL BE THE FOCUS FOR CONVECTION EACH DAY. IN ADDITION...PLENTY OF MOISTURE AVBL AS SEEN THRU MODEL SOUNDINGS. POPS WILL BE ADVERTISED HIER THAN CLIMO ESPECIALLY DURING DAYLIGHT HRS. WILL KEEP TEMPS A CAT OR 2 BELOW GFS MOS GUIDANCE. FOR WED THRU THU OF NEXT WEEK...MODELS IN GENERAL AGREEMENT IN RE-AMPLIFYING THE UPPER LONGWAVE PATTERN WITH MAJOR TROFFING ACROSS THE EASTERN 1/3 TO 1/2 OF THE U.S. AND RIDGING ACROSS THE WESTERN 1/2 TO 2/3 OF THE U.S. WHAT THIS MEANS FOR THE ILM CWA...IS THE OLD STATIONARY FRONTAL BOUNDARY TO FINALLY RELINQUISH ITS HOLD ACROSS THE FA. HOWEVER...THE COLD FRONT THAT FOLLOWS LATE IN THE PERIOD IS PROGGED TO GET THIS...STALL ACROSS THE BI-STATE REGION ONCE AGAIN. THIS BECAUSE THE NORTH TO SOUTH UPPER TROF AXIS IS PROGGED TO REMAIN WEST OF THE EASTERN CAROLINAS...THUS ELIMINATING ANY FURTHER SE PUSH TO THE COLD FRONT. POPS ONCE AGAIN WILL BE ADVERTISED ABOVE CLIMO DUE TO THE AVBL FORCING AND MOISTURE. WILL KEEP TEMPS NEAR CLIMO NORMS. && .AVIATION /00Z THURSDAY THROUGH TUESDAY/... AS OF 00Z...CONVECTION WINDING DOWN AT THE NORTH CAROLINA COAST. WILL KEEP VCSH IN THE ILM FOR THE FIRST COUPLE OF HOURS. OVERNIGHT LIGHT WINDS WITH SOME FOG DEVELOPING. VISIBILITIES WILL BE POOREST INLAND...WITH IFR POSSIBLE AFTER MIDNIGHT. FRIDAY...INCREASING CHANCES FOR CONVECTION AS LOW PRESSURE APPROACHES AND THE STATIONARY FRONT OVER THE REGION BEGINS TO WAVE NORTHWARD AS A WARM FRONT. FAIRLY HIGH CONFIDENCE FOR SCATTERED SHOWERS AND POSSIBLE STORMS AT THE INLAND TERMINALS AFTER 19Z. WINDS WILL BE LIGHT AND MAINLY EASTERLY. EXTENDED OUTLOOK...INCREASING CHANCES FOR SHOWERS/TSTMS AND PERIODS OF MVFR CONDITIONS THIS WEEKEND THROUGH TUESDAY AS A FRONT REMAINS STALLED. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 330 PM THURSDAY...THE SEA BREEZE HAS HELPED BRING A SOUTHERLY WIND TO THE NEAR SHORE WATERS WITH A WEAKER WEST WIND TO THE EAST OF THIS DENSITY CURRENT. A COLD FRONT IS FORECASTED TO STALL ALONG THE COAST THIS EVENING AND OVERNIGHT. WINDS ARE EXPECTED TO BE LIGHT AND VARIABLE AND LESS THAN 10 KNOTS DO TO A LACK OF A PRESSURE GRADIENT. WITH THE SWELL FROM THE FORMER TROPICAL STORM NOW A NON- PLAYER SEAS ARE EXPECTED TO BE AROUND 2 FEET THROUGH SUNRISE ON FRIDAY. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 330 PM THURSDAY...EXPECT EAST WINDS AROUND 10 KTS ON FRIDAY WITH 2-3 FT SEAS...HIGHEST OUTER WATERS. SEAS WILL BE A COMBINATION OF WEAK BACKGROUND SE SWELL AND LOCALLY GENERATED WIND WAVES. THE WINDS WILL BECOME SOUTHEAST AOB 10 KT OVERNIGHT FRI. AS A WARM FRONT LIFTS NORTHWARD ON SAT...STRENGTHENING SOUTHERLY FLOW WILL BUILD SEAS TO A SOLID 3 FT BY THE END OF THE PERIOD. SOUTH WINDS WILL BE IN THE 10-15 KT RANGE AFTER 00Z SUNDAY. LONG TERM /SUNDAY THROUGH TUESDAY/... AS OF 330 PM THURSDAY...NO ADVISORIES OR EXERCISE CAUTION THRESHOLDS MET THIS PERIOD. HATE TO SOUND LIKE A BROKEN RECORD BUT ONCE AGAIN THE WIND DIRECTION FORECAST THRUOUT THIS PERIOD WILL DEPEND ON THE POSITIONING OF THE MEANDERING FRONTAL BOUNDARY ACROSS THE AREA WATERS. OVERALL...HAVE STAYED CLOSE TO THE PREVIOUS WIND FORECAST ALONG WITH AVAILABLE GFS MODEL INPUT. THE WIND SPEEDS LOOK TO BE THE EASIER OF THE 2 WIND PARAMETERS. BASICALLY LOOKING AT WIND SPEEDS AT 15 KT OR LESS THRU THIS PERIOD. MODELS KEEP THE PROGGED SFC LOW ALONG THIS STALLED FRONT NORTH OF THE ILM WATERS. THAT IS WHERE THE PROGGED HIER WIND SPEEDS WILL RESIDE. THE THREAT FOR CONVECTION ACROSS THE ILM WATERS WILL OCCUR AT ALMOST ANY TIME DUE TO THE CLOSE PROXIMITY OF THIS STALLED BOUNDARY. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...MAINLY FROM AN ESE GROUND SWELL EXHIBITING 8 TO 10 SECOND PERIODS. SIGNIFICANT SEAS COULD REACH 4 FEET OFF CAPE FEAR DURING THE SUNDAY INTO MONDAY TIME FRAME. THE 4 FOOTERS WILL BE AIDED BY AN INCREASE OF 4 TO 6 SECOND PERIOD WIND DRIVEN WAVES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...BJR NEAR TERM...DRH SHORT TERM...BJR LONG TERM...DCH AVIATION...43 MARINE...DCH/BJR/DRH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
336 PM EDT THU AUG 7 2014 .SYNOPSIS... A COLD FRONT WILL SHIFT SOUTH OF THE REGION THROUGH TONIGHT AND WILL STALL ON FRIDAY. THIS FRONT WILL SLOWLY LIFT NORTHWARD OVER THE AREA THIS WEEKEND THROUGH EARLY NEXT WEEK...BRINGING RENEWED CHANCES OF SHOWERS AND THUNDERSTORMS EACH DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 PM THURSDAY...THE COLD FRONT WAS LOCATED ALONG A LINE FROM NEAR ELIZABETHTOWN THROUGH MARION TO JUST NORTH OF KINGSTREE. THE FRONT IS EXPECTED TO CONTINUE TO SLOWLY DRIFT SOUTH AND EAST THROUGH THE EVENING BEFORE STALLING AT THE COAST. LATEST RADAR IS SHOWING CONVECTION IN SOUTHERN PENDER COUNTY. ALSO...A FEW SHOWERS ARE STRUGGLING TO DEVELOP ALONG WEAK BOUNDARIES SEEN IN THE HIGH RESOLUTION RADAR DATA. WE CAN EVEN SEE A WEAK LAKE BREEZE BOUNDARY NORTH OF LAKE WACCAMAW BUT WITH THIS WEAK LOW LEVEL FORCING THE CONVECTION TO THE SOUTH IS STRUGGLING. THIS MAY BE THE HIGH LCL VALUES AND THE STORMS ARE NEEDING A BIT MORE LIFT THAN WHAT IS AVAILABLE AT THIS TIME. THE LATEST HRRR RUNS ARE SHOW CONVECTION A BIT MORE WIDESPREAD AND GENERALLY THE EAST OF THE FRONT. THE INSTABILITIES ARE RUNNING AROUND 2000 TO 2500 JOULES PER KILOGRAM TO THE EAST OF THE FRONT BUT THERE IS ABSOLUTE NO CONVERGENCE AT THE SURFACE WITH LIGHT WINDS. THE OTHER FORCING IN THE AREA OF CONCERN IS THE SEA BREEZE WHICH IS PINNED CLOSE TO THE COAST. THE HRRR IS NOT BULLISH ON CONVECTION ON THE SEA BREEZE BOUNDARY. SO HAVE A GONE WITH THE BEST CHANCES OF CONVECTION OVER THE EXTREME NORTHERN TIER OF COUNTIES CLOSER TO THE ONGOING CONVECTION AND A TAILING BAND OF ISOLATED CONVECTION ALONG THE COAST TO THE EAST OF THE FRONT. WITH THE FRONTAL BOUNDARY STALLING ALONG THE COAST...WE WILL CONTINUE WITH AN ISOLATED CHANCE OF SHOWERS OR A THUNDERSTORM ON THE EAST SIDE OF THE FRONT OVERNIGHT...BUT CONFIDENCE ON CONVECTION IS NOT THAT HIGH. TEMPERATURES OVERNIGHT ARE EXPECTED TO FALL INTO THE MIDDLE 70S ALONG THE COAST TO THE UPPER 60S TO NEAR 70 NORTH AND WEST OF INTERSTATES 20 AND 95. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 330 PM THURSDAY...A COLD FRONT WILL BE STALLED JUST SOUTH OF THE FORECAST AREA AT THE START OF THE PERIOD. FORECAST SOUNDINGS SHOW PLENTY OF DRY AIR IN THE MID LEVELS FRI MORNING...BUT THE COLUMN MOISTENS DURING THE DAY FROM WEST TO EAST. THE FRONT WILL GRADUALLY LIFT BACK NORTHWARD AS A WARM FRONT LATE FRI/EARLY SAT. THOUGH THE BEST ISENTROPIC ASCENT WILL REMAIN TO OUR WEST DURING FRI...WILL ADVERTISE SLIGHT TO CHC POPS ACROSS OUR FAR INLAND ZONES AS DEEPER MOISTURE SPREADS ACROSS THE CENTRAL CAROLINAS. POPS WILL REMAIN LOWER ALONG THE COAST DURING THE DAY FRI... GRADUALLY INCREASING OVERNIGHT INTO SAT MORNING. BY 12Z SAT THE WARM FRONT WILL BE DRAPED ACROSS OUR CWA...BRINGING AN EXTENDED PERIOD OF ABOVE NORMAL PCPN CHANCES AREA-WIDE. PWATS SURGE ABOVE 2.0 INCHES ON SAT AS SOUTHERLY LOW-LEVEL FLOW INCREASES BEHIND THE WARM FRONT. SHOWER COVERAGE IS EXPECTED TO BECOME MORE WIDESPREAD SAT AFTN AND THROUGH THE OVERNIGHT HOURS AS UPPER IMPULSES ALLOW WAVES OF LOW PRESSURE TO DEVELOP ALONG THE FRONT. GIVEN THE ANTECEDENT RAINFALL AND WEAK STEERING FLOW OF 5-10 KT AT BEST...LOCALLY HEAVY RAINFALL COULD RESULT IN MINOR FLOODING CONCERNS TOWARD THE END OF THE PERIOD. HIGH TEMPS ON FRIDAY WILL GENERALLY BE IN THE MID TO UPPER 80S... WITH LOWS DROPPING INTO THE LOWER 70S. HAVE SIDED WITH THE COOLER MET NUMBERS ON SATURDAY GIVEN THE EXPECTED CLOUD COVER AND INCREASED SHOWER COVERAGE DURING THE DAY. THIS YIELDED HIGHS IN THE MID 80S ACROSS THE AREA. && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 330 PM THURSDAY...LONGWAVE PATTERN TO MODIFY ACROSS THE CAROLINAS SUNDAY THRU TUESDAY WITH A LESS AMPLIFIED LONGWAVE TROF PERSISTING ACROSS THE CAROLINAS. AT THE SAME...A PROGRESSIVE S/W RIDGE TO BYPASS THE FA TO OUR NORTH...PUSHING ACROSS THE GREAT LAKES TO THE NE STATES DURING THIS TIME PERIOD. UNFORTUNATELY FOR THE ILM CWA...A MEANDERING FRONTAL BOUNDARY ACROSS THE CAROLINAS WILL GET LEFT BEHIND THRU TUESDAY AS IT BECOMES ORIENTED PARALLEL WITH THE UPPER FLOW. THE FORCING ALONG THIS FRONT WILL BE THE FOCUS FOR CONVECTION EACH DAY. IN ADDITION...PLENTY OF MOISTURE AVBL AS SEEN THRU MODEL SOUNDINGS. POPS WILL BE ADVERTISED HIER THAN CLIMO ESPECIALLY DURING DAYLIGHT HRS. WILL KEEP TEMPS A CAT OR 2 BELOW GFS MOS GUIDANCE. FOR WED THRU THU OF NEXT WEEK...MODELS IN GENERAL AGREEMENT IN RE-AMPLIFYING THE UPPER LONGWAVE PATTERN WITH MAJOR TROFFING ACROSS THE EASTERN 1/3 TO 1/2 OF THE U.S. AND RIDGING ACROSS THE WESTERN 1/2 TO 2/3 OF THE U.S. WHAT THIS MEANS FOR THE ILM CWA...IS THE OLD STATIONARY FRONTAL BOUNDARY TO FINALLY RELINQUISH ITS HOLD ACROSS THE FA. HOWEVER...THE COLD FRONT THAT FOLLOWS LATE IN THE PERIOD IS PROGGED TO GET THIS...STALL ACROSS THE BI-STATE REGION ONCE AGAIN. THIS BECAUSE THE NORTH TO SOUTH UPPER TROF AXIS IS PROGGED TO REMAIN WEST OF THE EASTERN CAROLINAS...THUS ELIMINATING ANY FURTHER SE PUSH TO THE COLD FRONT. POPS ONCE AGAIN WILL BE ADVERTISED ABOVE CLIMO DUE TO THE AVBL FORCING AND MOISTURE. WILL KEEP TEMPS NEAR CLIMO NORMS. && .AVIATION /20Z THURSDAY THROUGH TUESDAY/... AS OF 18Z...A COLD FRONT WILL BISECT THE INLAND AND COASTAL TERMINALS THIS AFTERNOON. WINDS WILL BE SE-S AT THE COASTAL TERMINALS AND NW-N AT THE INLAND TERMINALS. EXPECT SHOWERS AND ISOLATED THUNDERSTORMS TO CONTINUE TO DEVELOP THIS AFTERNOON. DUE TO DRYING IN THE MID/UPPER LEVELS ACTUAL PRECIPITATION CHANCES PER MOS GUIDANCE ARE LOW...BUT FAVORED AREAS OF DEVELOPMENT WILL BE ALONG THE FRONT...AND ALONG THE SEA BREEZE BOUNDARY. AS DRYING INCREASES THIS EVENING COUPLED WITH LOSS OF HEATING EXPECT ANY SHOWER ACTIVITY TO DISSIPATE. VFR EXPECTED THIS EVENING AS WINDS BECOME LIGHT/VRBL. MVFR VSBYS IN BR WILL DEVELOP OVERNIGHT...WITH HIGHEST CONFIDENCE KFLO/KLBT. KFLO/KLBT WILL HAVE A REASONABLE SHOT OF IFR/LIFR VSBYS/CIGS AFTER 08Z. VFR DEVELOPS SHORTLY AFTER SUNRISE AT KFLO/KLBT. TEMPO MVFR CIGS ARE POSSIBLE AT THE COASTAL TERMINALS DURING THE MORNING BUT CONFIDENCE IS LOW. WINDS WILL BE ENE-ESE. EXTENDED OUTLOOK...ISOLATED SHOWERS POSSIBLE ON FRIDAY. INCREASING CHANCES FOR SHOWERS/TSTMS AND PERIODS OF MVFR CONDITIONS THIS WEEKEND THROUGH TUESDAY AS A FRONT REMAINS STALLED. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 330 PM THURSDAY...THE SEA BREEZE HAS HELPED BRING A SOUTHERLY WIND TO THE NEAR SHORE WATERS WITH A WEAKER WEST WIND TO THE EAST OF THIS DENSITY CURRENT. A COLD FRONT IS FORECASTED TO STALL ALONG THE COAST THIS EVENING AND OVERNIGHT. WINDS ARE EXPECTED TO BE LIGHT AND VARIABLE AND LESS THAN 10 KNOTS DO TO A LACK OF A PRESSURE GRADIENT. WITH THE SWELL FROM THE FORMER TROPICAL STORM NOW A NON- PLAYER SEAS ARE EXPECTED TO BE AROUND 2 FEET THROUGH SUNRISE ON FRIDAY. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 330 PM THURSDAY...EXPECT EAST WINDS AROUND 10 KTS ON FRIDAY WITH 2-3 FT SEAS...HIGHEST OUTER WATERS. SEAS WILL BE A COMBINATION OF WEAK BACKGROUND SE SWELL AND LOCALLY GENERATED WIND WAVES. THE WINDS WILL BECOME SOUTHEAST AOB 10 KT OVERNIGHT FRI. AS A WARM FRONT LIFTS NORTHWARD ON SAT...STRENGTHENING SOUTHERLY FLOW WILL BUILD SEAS TO A SOLID 3 FT BY THE END OF THE PERIOD. SOUTH WINDS WILL BE IN THE 10-15 KT RANGE AFTER 00Z SUNDAY. LONG TERM /SUNDAY THROUGH TUESDAY/... AS OF 330 PM THURSDAY...NO ADVISORIES OR EXERCISE CAUTION THRESHOLDS MET THIS PERIOD. HATE TO SOUND LIKE A BROKEN RECORD BUT ONCE AGAIN THE WIND DIRECTION FORECAST THRUOUT THIS PERIOD WILL DEPEND ON THE POSITIONING OF THE MEANDERING FRONTAL BOUNDARY ACROSS THE AREA WATERS. OVERALL...HAVE STAYED CLOSE TO THE PREVIOUS WIND FORECAST ALONG WITH AVAILABLE GFS MODEL INPUT. THE WIND SPEEDS LOOK TO BE THE EASIER OF THE 2 WIND PARAMETERS. BASICALLY LOOKING AT WIND SPEEDS AT 15 KT OR LESS THRU THIS PERIOD. MODELS KEEP THE PROGGED SFC LOW ALONG THIS STALLED FRONT NORTH OF THE ILM WATERS. THAT IS WHERE THE PROGGED HIER WIND SPEEDS WILL RESIDE. THE THREAT FOR CONVECTION ACROSS THE ILM WATERS WILL OCCUR AT ALMOST ANY TIME DUE TO THE CLOSE PROXIMITY OF THIS STALLED BOUNDARY. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...MAINLY FROM AN ESE GROUND SWELL EXHIBITING 8 TO 10 SECOND PERIODS. SIGNIFICANT SEAS COULD REACH 4 FEET OFF CAPE FEAR DURING THE SUNDAY INTO MONDAY TIME FRAME. THE 4 FOOTERS WILL BE AIDED BY AN INCREASE OF 4 TO 6 SECOND PERIOD WIND DRIVEN WAVES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...BJR NEAR TERM...DRH SHORT TERM...BJR LONG TERM...DCH AVIATION...MRR MARINE...DCH/BJR/DRH
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
332 PM CDT THU AUG 7 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 213 PM CDT THU AUG 7 2014 BAND OF LIGHT RAIN AND DRIZZLE REMAINS LARGELY FOCUSED ON NORTHWEST IOWA THIS AFTERNOON...WITH A SECONDARY AREA OF WIDELY SCATTERED LIGHT SHOWERS OR SPRINKLES EXPANDING INTO FAR SOUTHEAST SD AND NORTHWEST MN. RECENT RAP AND HRRR MODELS ARE HANDLING THESE AREAS FAIRLY WELL. EXPECT THE LIGHT PRECIPITATION TO GRADUALLY TAPER LATE AFTERNOON INTO THE EVENING AS THE UPPER LEVEL SUPPORT SLOWLY SLIPS TO OUR SOUTHEAST AND WEAK RIDGING TRIES TO NOSE INTO NORTH CENTRAL NEBRASKA...HOWEVER WITH PERSISTENT MID LEVEL MOISTURE...THERE MIGHT BE SOME RESIDUAL SPRINKLES OR DRIZZLE -NON MEASURABLE - LASTING INTO THE OVERNIGHT HOURS...MAINLY ACROSS OUR EASTERN HALF. STRATUS WILL CONTINUE TO BLANKET THE AREA OVERNIGHT...HOWEVER LIGHT EASTERLY WINDS AND RESIDUAL LOW LEVEL MOISTURE WILL LIKELY ALLOW SOME PATCHY FOG TO ONCE AGAIN LATE FORM TONIGHT. NOT EXPECTING WIDESPREAD DENSE FOG. LOWS TONIGHT WILL RANGE FROM NEAR 60 TO 65. WITH COOL AND MOIST MID LEVELS PERSISTING INTO FRIDAY...DO NOT EXPECT TOO MUCH IMPROVEMENT IN THE MAINLY OVERCAST SKIES ACROSS THE AREA. MODELS BRING A SHORTWAVE ACROSS NORTHERN NEBRASKA DURING THE DAY...WHICH WILL ALLOW ISOLATED TO SCATTERED SHOWERS TO DEVELOP WITH A FEW NON SEVERE THUNDERSTORMS POSSIBLE. EXPECT THIS THREAT TO BE MAINLY NEAR THE MISSOURI VALLEY INTO SOUTH CENTRAL SOUTH DAKOTA. AGAIN...WITH SOME DISORGANIZED MID LEVEL SUPPORT COULD SEE A FEW LIGHT SHOWERS OR SPRINKLES FURTHER EAST ACROSS THE REST OF THE FORECAST AREA MAINLY IN THE AFTERNOON. HIGHS WILL BE IN THE MID 70S TO AROUND 80 DEGREES. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 213 PM CDT THU AUG 7 2014 WEAK H5 FLOW EARLY IN THE PD WONT HELP FOCUS ANY WIDESPREAD PRECIP. ON FRI NIGHT...H85 THERMAL GRADIENT AND A WEAK BOUNDARY ALL WEST OF THE JAMES...WILL PROVIDE SOME IMPETUS FOR SCT TSRA DEVELOPMENT OVERNIGHT. THESE FEATURES WILL MOVE EAST INTO SATURDAY MORNING/AFTERNOON SO HAVE INCLUDED LOW CHANCE POPS THRU THE ENTIRE CWA. SAT NIGHT INTO SUNDAY...A MORE ORGANIZED WAVE AT H5 AND H7 BEGIN TO IMPACT THE CWA. POPS ARE STILL IN THE CHANCE CAT AS A COOL FRONT PASSES THROUGH BY SUNDAY AFTERNOON WITH REALLY JUST WEAK SFC CONVERGENCE. NO SIGNIFICANT RAIN IS EXPECTED WITH FROPA. FROM MONDAY TO FRIDAY OVERALL PATTERN TURNS TO RIDGING OVER THE ROCKIES AND A CLOSED LOW OFF THE CA/OR COAST. THIS LOW WILL EJECT SEVERAL ROUNDS OF SHWVS OVER THE RIDGE INTO THE NW FLOW OVER THE CWA BRINGING LOW CHANCES OF TSRA EVERY OTHER DAY. A LITTLE STRONGER WAVE/TROF APPROACHES ON WED/THURS SO HIGHER CHANCE POPS ARE IN PLACE THEN. TEMPS THRU THE PD WILL REMAIN AT OR SLIGHTLY BELOW NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 117 PM CDT THU AUG 7 2014 MVFR AND IFR STRATUS CONTINUES TO BLANKET THE AREA...WITH SOME RESIDUAL MVFR VISIBILITY IN MIST AND DRIZZLE. SCATTERED LIGHT RAIN SHOWERS WILL CONTINUE TO SPREAD ACROSS NORTHWEST IOWA INTO FAR EASTERN SOUTH DAKOTA AND SOUTHWEST MINNESOTA...THEN GRADUALLY DIMINISH THIS EVENING INTO THE EARLY MORNING HOURS. EXPECT CEILINGS TO REMAIN PRIMARILY MVFR AND COULD DROP TO IFR AGAIN TONIGHT IN PATCHY FOG. ADDED LOWER VISIBILITY TO 2 SM FROM 09 TO 12Z IN ALL TAF SITES WITH LIGHT WINDS AND LOW LEVEL MOISTURE PRESENT. NOT SEEING MUCH IMPROVEMENT THROUGH THE END OF THE TAF PERIOD. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM... LONG TERM...SALLY AVIATION...
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
117 PM CDT THU AUG 7 2014 .DISCUSSION... UPDATED FOR 18Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1017 AM CDT THU AUG 7 2014/ UPDATE... A DYING MCS CONTINUES TO MOVE TOWARD THE MIDSOUTH. A FEW SHOWERS AND THUNDERSTORMS ON THE LEADING EDGE HAVE MOVED INTO NORTHEAST ARKANSAS AND THE MO BOOTHEEL AT THIS TIME. THE MCS IS ASSOCIATED WITH AN UPPER TROF THAT WILL MOVE INTO THE MIDSOUTH TODAY. THE LATEST HRRR AND 12Z NAM SHOW CONVECTION EITHER CONTINUING OR REDEVELOPING IN ASSOCIATION WITH THIS TROF. WOULD EXPECT BY EARLY THIS AFTERNOON TO SEE NUMEROUS SHOWERS AND THUNDERSTORMS OVER THE AT LEAST THE NORTHWEST HALF OF THE CWA. THE LIKELY POPS LOOK GOOD. HIGH TEMPERATURES MAY BE A TAD HIGH IF THE CONVECTION OCCURS LIKE THE MODELS ARE SHOWING BUT FOR NOW WILL LEAVE HIGH TEMPS ALONE. CURRENT FORECAST LOOKS GOOD...NO UPDATES ARE EXPECTED AT THIS TIME. KRM DISCUSSION... /ISSUED 324 AM CDT THU AUG 7 2014/ CURRENT WEATHER TONIGHT IS CLOSE TO A COPY AS IT GETS FROM LAST NIGHT. THE ONLY DIFFERENCE IS A SLOWLY APPROACHING MCS IN SOUTHWEST MISSOURI. TEMPERATURES ARE IN THE UPPER 60S TO MID 70S WITH CALM OR LIGHT WINDS. FOR TODAY THROUGH SATURDAY...MODELS ARE IN GOOD AGREEMENT THAT THE AFOREMENTIONED MCS/APPROACHING PLAINS SHORTWAVE WILL SLOWLY MOVE ACROSS THE MIDSOUTH THROUGHOUT THE DAY...WITH LIKELY REDEVELOPMENT IN NORTHWEST FLOW ON THE UPWIND SIDE TONIGHT AND TOMORROW. IT APPEARS THE BRUNT OF THE RAINFALL WILL FALL ACROSS THE NORTHERN TWO THIRDS OF THE CWA. INCREASING BOUNDARY LAYER MOISTURE TODAY WILL DRIVE CURRENT PW`S NEAR 1.50 INCHES...TO ABOVE 2 INCHES BY TONIGHT...THEN HOLD CLOSE TO 2 INCHES FOR MOST OF THE AREA THROUGH THE WEEKEND. FOR NOW KEEPING ANY FLASH FLOODING MORE LOCALIZED AS SEVERAL MIDSOUTH COUNTIES HAVE NOT HAD A GOOD SOAKING RAIN IN OVER TWO WEEKS. IN ADDITION THE POTENTIAL FOR STRONG AND SEVERE STORMS WILL BE SEEN DURING EACH AFTERNOON AND EVENING AS CAPE VALUES CLIMB TO 3000 J/KG AND LI`S DIP TO NEAR -10C. THOUGH THE ATMOSPHERE WILL NOT BE AS CONDUCIVE FOR LARGE HAIL FORMATION...IT WILL BE FOR DOWNBURSTS AND STRAIGHT LINE WINDS. TEMPERATURES WILL REMAIN SEASONAL TODAY...BECOMING SLIGHTLY BELOW NORMAL FOR TOMORROW AND SATURDAY. HIGH HUMIDITY THROUGH THE PERIOD WILL GENERATE AFTERNOON HEAT INDICES IN THE MID 90S...TO LOW 100S. SUNDAY THROUGH WEDNESDAY...THE GFS AND EURO HAVE SIMILAR SOLUTIONS THIS PERIOD WITH DIFFERENCES IN TIMING...CURRENTLY THE GFS IS FASTER. A DEEPER TROUGH IS ANTICIPATED TO DEVELOP OVER THE EASTERN THIRD OF THE COUNTRY. THIS IN TURN WILL ALLOW FOR A WEAK COLD FRONT TO SLIP THROUGH THE MIDSOUTH. DUE TO THE EXPECTED WORKED OVER ATMOSPHERE FROM THE CONVECTION EARLIER IN THE WEEKEND...AND SLIGHTLY DRIER AND MORE STABLE AIR WORKING IT`S WAY SOUTH AND EAST...RAIN CHANCES SHOULD SLOWLY TAPER OFF EACH DAY. TEMPERATURES WILL CHANGE LITTLE EARLY NEXT WEEK WITH HIGHS STAYING A DEGREE OR TWO BELOW NORMAL. JAB .AVIATION... 18Z TAF CYCLE SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL CONTINUE TO DEVELOP ACROSS THE MIDSOUTH THIS AFTERNOON. GIVEN LATEST RADAR AND SHORT RANGE MODEL TRENDS KEPT TEMPO GROUPS FOR TSRA AT KMEM...KMKL...AND KJBR AND ADDED ONE AT KTUP. SHORT RANGE MODELS POINTS TOWARD A BREAK IN ACTIVITY DURING THE EVENING THEN REDEVELOPMENT LATER TONIGHT INTO FRIDAY MORNING. EXPECT MAINLY VFR CONDS OUTSIDE OF SHRA/TSRAS AND MVFR...POSSIBLY IFR CONDS INVOF SHRAS/TSRAS. SW WINDS 6-10 KTS WITH SOME HIGHER GUSTS AT KMEM AND KJBR THIS AFTERNOON. LIGHT SOUTH OVERNIGHT SWITCHING TO SW FRIDAY MORNING. SJM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
310 PM CDT THU AUG 7 2014 .SHORT TERM (TONIGHT THROUGH FRIDAY NIGHT)... COVERAGE OF AFTERNOON CU IS LESS THAN PREVIOUS DAYS AS SLIGHTLY DRIER AIR IS IN PLACE ACROSS SOUTH CENTRAL TEXAS. THE HRRR AND OTHER HIGH-RES MODELS CONTINUE TO FORECAST WAY TOO MUCH CONVECTION EACH AFTERNOON AND WILL KEEP THE FORECAST DRY FOR THE REMAINDER OF THE DAY. TOMORROW ALSO SHOULD REMAIN DRY AS PW VALUES REMAIN AROUND 1.5 TO 1.6 INCHES. THE HEAT WILL BE THE MAIN STORY WITH HIGHS IN THE UPPER 90S TO 104 ACROSS THE REGION. DEWPOINTS ACROSS THE COASTAL PLAINS WILL ONLY MIX OUT TO THE MIDDLE TO UPPER 60S. THIS SHOULD LEAD TO HEAT INDICES TOMORROW IN THE 103 TO 105 DEGREE RANGE. WILL CONTINUE TO HIGHLIGHT THIS IN THE HWO BUT A HEAT ADVISORY IS NOT NEEDED. LOWS TONIGHT AND FRIDAY NIGHT WILL BOTTOM OUT IN THE LOWER TO UPPER 70S. && .LONG TERM (SATURDAY THROUGH THURSDAY)... THIS WEEKEND....A WEAK UPPER LOW/TUTT WILL MOVE INTO NORTHERN MEXICO THEN MOVE NORTHWEST NEAR THE RIO GRANDE RIVER. THE FLOW AROUND THE LOW SHOULD BRING IN SLIGHTLY HIGHER MOISTURE VALUES TO THE REGION SATURDAY AND SUNDAY. THIS SHOULD ALLOW A SLIGHT CHANCE OF AFTERNOON SHOWERS AND STORMS ACROSS THE FAR SOUTHEASTERN COUNTIES. WILL ALSO SHOW SLIGHT CHANCE POPS FOR AREAS NEAR THE RIO GRANDE AS WEAK LIFT ASSOCIATED WITH THE UPPER LOW COULD CAUSE A FEW SHOWERS AND THUNDERSTORMS. NO WIDESPREAD RAIN IS EXPECTED THIS WEEKEND. THE FORECAST FOR THE BEGINNING OF THE WEEK IS MOSTLY THE SAME...BUT THE MODELS ARE NOW HINTING AT A DIFFERENT PATTERN SHAPING UP BY TUESDAY/WEDNESDAY. INSTEAD OF THE RETURN OF A RIDGE ACROSS TEXAS FOR SEVERAL DAYS. MODELS ARE NOW FORECASTING A TROUGH TO DROP INTO THE THE NORTHEASTERN CONUS BY TUESDAY. THIS WOULD ALLOW THE RIDGE TO RE-CENTER AND AMPLIFY ACROSS NEW MEXICO AND COLORADO. THE ECMWF AND GFS ARE IN FAIRLY GOOD AGREEMENT THAT A WEAK FRONT WILL MOVE INTO NORTH TEXAS TUESDAY OR TUESDAY NIGHT WHICH COULD BRING RAIN CHANCES TO MOST OF SOUTH-CENTRAL TEXAS SOMETIME IN THIS TIME FRAME. THIS SOLUTION IS ALSO SOMEWHAT SUPPORTED BY MOST OF THE GFS ENSEMBLE MEMBERS...THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM AND THE CANADIAN. THERE ARE QUESTIONS OF HOW FAR ANY POTENTIAL FRONT WILL MAKE IT AND ALSO THE BEST TIMING FOR RAIN CHANCES. WILL KEEP THE FORECAST DRY FOR NOW AS THIS IS A CHANGE FROM PREVIOUS RUNS...BUT IT BEARS WATCHING. TUESDAY AHEAD OF ANY POTENTIAL FRONT WILL BE ONE OF THE HOTTEST DAYS OF THE YEAR. THE GFS AND ECMWF ARE BOTH FORECASTING 850 TEMPS TO BE THE HIGHEST WE HAVE SEEN THIS YEAR...RANGING FROM 22 TO 25 C. MOST LOCATIONS...EXCLUDING THE HILL COUNTRY SHOULD SEE THE CENTURY MARK. WILL COOL TEMPERATURES SLIGHTLY WEDNESDAY AND THURSDAY TO ACCOUNT FOR POTENTIAL CLOUD COVER ASSOCIATED WITH A FRONT IN NORTH TEXAS. ANOTHER TROUGH/COLD FRONT IS HINTED AT BY THE GFS AND ECMWF BEYOND THIS FORECAST PERIOD. HOWEVER...ONCE AGAIN THE MAIN TROUGH AXIS WILL BE EAST OF THE AREA AND WE WILL HAVE TO WAIT AND SEE WHAT TYPE OF IMPACTS THIS MAY HAVE ON OUR WEATHER. HAMPSHIRE && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 76 101 75 99 75 / 0 - - - - AUSTIN BERGSTROM INTL AIRPORT 74 100 72 100 72 / 0 - - - - NEW BRAUNFELS MUNI AIRPORT 73 101 72 100 72 / - - - - 10 BURNET MUNI AIRPORT 74 99 73 99 73 / 0 - - - - DEL RIO INTL AIRPORT 78 100 78 99 77 / 0 - - - 10 GEORGETOWN MUNI AIRPORT 75 99 74 99 74 / 0 - - - - HONDO MUNI AIRPORT 73 100 72 98 72 / - - - - 10 SAN MARCOS MUNI AIRPORT 74 100 73 99 73 / - - - - 10 LA GRANGE - FAYETTE REGIONAL 77 99 76 98 75 / - - - - 10 SAN ANTONIO INTL AIRPORT 76 100 76 98 76 / - - - - 10 STINSON MUNI AIRPORT 75 101 74 99 75 / - - - - 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...09 SYNOPTIC/GRIDS...29 PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1248 PM CDT THU AUG 7 2014 .AVIATION... VFR IS EXPECTED THROUGH THE OVERNIGHT HOURS. WE HAD ANOTHER MORNING OF MVFR ACROSS AUS/SAT/SSF...AND DECIDED TO GO WITH PERSISTENCE AND BRING IT IN AGAIN TOMORROW MORNING FROM 11-14Z IN A TEMPO GROUP FOR THOSE LOCATIONS. LATEST SIMULATED WRF DOES NOT HAVE THE CLOUDS IN FOR FRIDAY MORNING SO LATER SHIFTS SHOULD WATCH CLOSELY. SOUTHERLY WINDS MAINLY AROUND THE 10-15 KT RANGE. && .PREV DISCUSSION... /ISSUED 1030 AM CDT THU AUG 7 2014/ UPDATE... SOUTHWEST WINDS AT THE SURFACE THIS MORNING HAS WARMED UP TEMPERATURES A BIT FASTER THAN ANTICIPATED. CURRENT READINGS ARE ABOUT 1-3 DEGREES WARMER THAN THIS TIME YESTERDAY. WILL BUMP UP HIGHS A DEGREE OR TWO. THE HRRR CONTINUES TO OVERDO ITS CONVECTION FORECAST AND WILL LEAVE THE FORECAST DRY. OTHERWISE...NO MAJOR CHANGES TO THE CURRENT FORECAST. HAMPSHIRE PREV DISCUSSION... /ISSUED 637 AM CDT THU AUG 7 2014/ AVIATION... /12Z TAF DISCUSSION/ INTERMITTENT MVFR CIGS ARE EXPECTED TO AFFECT I-35 TERMINAL SITES FROM 09Z TO 15Z THE NEXT COUPLE MORNINGS. DAYTIME SOUTHERLY WINDS WILL BE UP TODAY OVER PREVIOUS DAYS SINCE A SHALLOW UPPER TROUGH WILL BE PASSING FROM THE GREAT BASING INTO THE CENTRAL PLAINS. PREV DISCUSSION... /ISSUED 347 AM CDT THU AUG 7 2014/ SHORT TERM (TODAY THROUGH FRIDAY)... A SMALL PATCH OF MVFR STRATOCUMULUS HAS DEVELOPED ACROSS THE COASTAL PLAINS THIS MORNING. WE EXPECT THIS TO SPREAD INLAND ABOUT TO I-35...THEN SCATTER OUT QUICKLY BY MID- MORNING WITH DAYTIME MIXING. A SIMILAR PATTERN OF CLOUD DEVELOPMENT AND POSSIBLY PATCHY FOG IS EXPECTED FRIDAY AND SATURDAY MORNINGS AS WELL. OTHERWISE... THE UPPER LEVEL RIDGE IS IN PLACE AND SHOULD LIMIT ANY CONVECTION TO VERY ISOLATED...SHORT-LIVED SHOWERS. TEMPERATURES WILL CONTINUE TO RUN ABOVE NORMAL IN THE UPPER 90S TO NEAR 100. LONG TERM (FRIDAY NIGHT THROUGH WEDNESDAY)... THE MODELS ARE IN GOOD AGREEMENT WITH MOVING A TUTT LOW NORTHWESTWARD ALONG THE RIO GRANDE IN MEXICO OVER THE WEEKEND. WE INCLUDED A 20 PCT POP FOR THE RIO GRANDE PLAINS TO COVER THIS SATURDAY EVENING AND SUNDAY. THE UPPER LEVEL RIDGE GETS STRONGER EARLY NEXT WEEK...SO EXPECT THE HOTTEST DAY(S) OF THE SUMMER MONDAY AND TUESDAY. THE RIDGE THEN SHIFTS WEST OVER THE ROCKIES AS A NEW TROUGH IS CARVED OUT OVER THE GREAT LAKES. THE GFS INDICATES A SHORT-WAVE TROUGH MAY DROP OUT OF THE MEAN LONGWAVE TROUGH AND BRING SOME RAIN AUGUST 15-17TH...BUT THE ECMWF DOES NOT SHOW THAT...SO WE WILL KEEP THE FORECAST DRY FOR NOW. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 100 76 99 75 98 / - - - - - AUSTIN BERGSTROM INTL AIRPORT 100 73 100 72 98 / - - - - - NEW BRAUNFELS MUNI AIRPORT 101 73 100 72 99 / - - - - - BURNET MUNI AIRPORT 100 74 98 73 97 / - - - - - DEL RIO INTL AIRPORT 102 78 101 77 98 / 10 - - - - GEORGETOWN MUNI AIRPORT 99 75 98 74 97 / - - - - - HONDO MUNI AIRPORT 100 73 98 72 97 / - - - - - SAN MARCOS MUNI AIRPORT 100 73 99 73 98 / - - - - - LA GRANGE - FAYETTE REGIONAL 99 76 98 75 97 / 10 - - 10 - SAN ANTONIO INTL AIRPORT 100 76 98 76 97 / - - - - - STINSON MUNI AIRPORT 100 75 99 74 98 / - - - - - && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...09 SYNOPTIC/GRIDS...29 PUBLIC SERVICE/DATA COLLECTION...32