Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/29/15


AREA FORECAST DISCUSSION
NWS RENO NV
832 PM PDT SUN JUN 28 2015 .UPDATE... CONVECTION HAS BECOME ISOLATED OVER THE NORTHEAST PART OF THE CWA THIS EVENING WITH SOME VERY LIGHT RETURNS ALSO SHOWING UP SOUTH OF LAKE TAHOE. THE LATEST NAM MODEL GUIDANCE AND THE HRRR DO SHOW SOME REDEVELOPMENT LATER THIS EVENING AND OVERNIGHT AS A SHORT WAVE IN SOUTHERN CALIFORNIA LIFTS NORTH. FORCING IS NOT OVERWHELMING WITH THIS FEATURE...BUT ITS MERE PRESENCE ARGUES FOR KEEPING AT LEAST A SLIGHT CHANCE FOR THE LATE EVENING HOURS FOR MUCH OF THE AREA AND A FEW SHOWERS OVER THE FAR SOUTHWEST CWA OVERNIGHT. WILL MAKE A FEW MINOR ADJUSTMENTS AND GET UPDATES OUT SOON. 20 && .PREVIOUS DISCUSSION... /ISSUED 119 PM PDT SUN JUN 28 2015/ SYNOPSIS... HIGH PRESSURE OVER THE GREAT BASIN WILL STRENGTHEN THIS WEEK AND RESULT IN TEMPERATURES WARMING BACK TO UNSEASONABLY HOT LEVELS. MOISTURE WILL REMAIN TRAPPED UNDERNEATH RIDGE AND ALLOW FOR AT LEAST A SMALL CHANCE OF THUNDERSTORMS EACH DAY. SHORT TERM... MOISTURE CONTINUES TO STREAM NORTHWARD INTO THE SIERRA AND WESTERN NV IN ADVANCE OF UPPER LOW OFF THE CA COAST. CLOUD COVER HAS LIMITED DAYTIME HEATING TO THIS POINT WITH TEMPERATURES AS MUCH AS 5-10 DEGREES COOLER OUTSIDE THE BASIN AND RANGE COMPARED TO SATURDAY AT THIS TIME. EARLIER HIGH RESOLUTION MODELS HAD BEEN SHOWING STORMS WITH AN IMPRESSIVE OUTFLOW WORKING ACROSS WESTERN NV. HOWEVER THE MOST RECENT RUNS HAVE BACKED OFF A BIT AND ARE WEAKER WITH THE OUTFLOW MAGNITUDE ALTHOUGH THEY DO STILL SHOW THIS FEATURE. THEREFORE THE POTENTIAL STILL EXISTS FOR ISOLD-SCT STORMS FOR THE LATTER HALF OF THE AFTERNOON AND EVENING, ALTHOUGH THEY MAY NOT GET AS STRONG AS FORECAST DUE TO LIMITED INSTABILITY FROM THE LACK OF AFTERNOON HEATING. THE WESTERN PART OF THE TAHOE BASIN INTO WESTERN LASSEN COUNTY HAS RECEIVED A LONGER DURATION OF SUNSHINE WITH SOME CLEARING NOTED SOUTH OF MAMMOTH. THESE AREAS HAVE A BETTER CHANCE OF SEEING STORM INITIATION. OTHERWISE, UPPER LOW OFF THE COAST WILL EJECT TONIGHT AND THIS SHOULD BRING SOME DRIER AND MORE STABLE AIR INTO NORTHEAST CA AND NORTHWEST NV FOR MONDAY. THE GFS IS SHOWING SOME WEAK QPF SIGNALS THERE, BUT BELIEVE THAT THE BEST INSTABILITY WILL BE SOUTH OF ABOUT I-80 WITH THE BEST CHANCE OF THUNDERSTORMS ALONG THE EASTERN SIERRA FROM LAKE TAHOE SOUTHWARD. NOT MUCH CHANGE IS EXPECTED OVERALL IN THE THREAT FOR THUNDERSTORMS TUE-WED, ALTHOUGH COVERAGE MAY DECREASE A BIT AS THE RIDGE OVER THE GREAT BASIN BEGINS TO EXPAND WESTWARD ONCE AGAIN. HOWEVER, DESPITE THE OVERALL DECREASE IN AREAL COVERAGE OF STORMS, ANY STORMS THAT DO DEVELOP WILL BE CAPABLE OF HEAVY RAINFALL AND THIS WILL CONTINUE TO BE A CONCERN FOR BURN SCARS INCLUDING THE WASHINGTON FIRE. TEMPERATURES WILL BEGIN TO PUSH 100 DEGREES ONCE AGAIN WITH THIS ROUND OF HEAT LOOKING MORE IMPRESSIVE THAN THE ONE WE JUST EXPERIENCED. WE ARE CANCELING THE HEAT ADVISORY FOR BASIN AND RANGE WITH THIS PACKAGE AS TEMPERATURES ARE NOT EXPECTED TO REACH CRITERIA THIS AFTERNOON. HOWEVER, ANOTHER ADVISORY MAY BE NEEDED BY MIDWEEK. HOHMANN LONG TERM...WEDNESDAY THROUGH SATURDAY... THE FORECAST REMAINS ON TRACK FOR A HIGH PRESSURE RIDGE OVER THE GREAT BASIN TO MAINTAIN A VERY HOT AIR MASS THROUGH THE END OF THE WEEK. PREPARE FOR VERY HOT TEMPERATURES ALL WEEK, WITH HIGHS WED-THU 85-95 FOR MOST SIERRA COMMUNITIES AND 100-110 FOR WESTERN NV. THIS STRETCH OF SEVERAL HOT DAYS ALONG WITH WARM NIGHTS MEANS THE RISK FOR HEAT EXHAUSTION AND DEHYDRATION WILL INCREASE EACH DAY, ESPECIALLY FOR ANYONE WORKING OUTDOORS OR WITHOUT AIR CONDITIONING. CARRY EXTRA WATER AND PLAN TO CHECK ON ANYONE SUSCEPTIBLE TO HEAT STRESS. SOUTHERLY FLOW ALONG THE WESTERN PERIMETER OF THE RIDGE BRINGS MOISTURE AND POTENTIAL FOR THUNDERSTORMS EACH AFTERNOON/EVENING THROUGH THE END OF THE WEEK, WITH THE BEST CHANCES OVER THE SIERRA FROM THE TAHOE BASIN SOUTH. FOR FRIDAY-SATURDAY, THERE CONTINUE TO BE DIFFERENCES AMONG MODEL FORECASTS IN THE EVOLUTION OF THE RIDGE AS A TROUGH MOVES ACROSS THE PACIFIC NORTHWEST. THE CONSENSUS IS FOR THE GREAT BASIN RIDGE TO SHIFT A LITTLE TO THE EAST, SO WE MAINTAINED THE FORECAST FOR A VERY SLIGHT COOLING TREND GOING INTO THE WEEKEND. THERE IS ALSO POTENTIAL FOR THUNDERSTORMS TO DEVELOP EACH AFTERNOON THROUGHOUT THE WEEKEND. JCM AVIATION... MAIN THREAT TODAY WILL BE TSRA THRU 03Z WITH A 20-30 PCT CHANCE OF TERMINALS BEING AFFECTED. STRONG OUTFLOW WINDS MAY CREATE SUDDEN CHANGES IN WIND DIRECTION ALONG WITH GUSTS TO 35 KTS. FOR WESTERN NV TERMINALS, INCLUDING KLOL, THESE WINDS MAY CREATE SUDDEN RESTRICTIONS IN VISIBILITY DUE TO BLOWING DUST. SMALL THREAT OF STRONGER SFC WND GUSTS TO 45 KTS (5 PCT AT ANY ONE POINT). OTHERWISE VFR CONDITIONS OUTSIDE OF TSTORMS TODAY WITH CLEARING OVERNIGHT. A FEW MORE -TSRA POSSIBLE MONDAY, BUT CHANCE WILL BE MAINLY CONFINED TO THE SIERRA FROM TAHOE SOUTH AND INTO PARTS OF EXTREME WRN NV. WALLMANN/MITTELSTADT && .REV WATCHES/WARNINGS/ADVISORIES... NV...NONE. CA...NONE. && $$ FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE VISIT... HTTP://WEATHER.GOV/RENO (ALL LOWER CASE)
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1112 AM MDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM MDT SAT JUN 27 2015 CURRENTLY... RADAR IMAGERY SHOWS SCT TSRA SHOWERS OVER THE FAR SRN EXTENT OF THE SANGRE DE CRISTO MTNS ASSOCIATED WITH A WEAK SHORTWAVE FEATURE LOCATED OVER SOUTHERN CO. SHOWERS ARE PROGGED TO CONTINUE TO MOVE SOUTH OVER THE NEXT FEW HOURS WITH ACTIVITY DECREASING INTO THE EARLY MORNING HOURS. TODAY... AN OMEGA BLOCK WILL REMAIN CENTERED OVER UTAH TODAY AND TONIGHT...MAINTAINING A PERIOD OF GENERALLY CALM WEATHER OVER MOST OF THE CWA. LATEST 07Z HRRR GUIDANCE CONTINUES TO SUPPORT THE DEVELOPMENT OF A STRATUS LAYER ALONG THE I-25 CORRIDOR...WITH THE BEST CHANCE OF DEVELOPMENT IN EL PASO COUNTY. GENERALLY WEAK SE UPSLOPE FLOW WILL AIDE IN STRATUS FORMATION...HOWEVER WINDS WILL TRANSITION TO A WESTERLY COMPONENT AROUND 14Z ALLOWING FOR THE LIFTING OF ANY STRATUS THAT DOES DEVELOP. DIURNALLY DRIVEN MTN THUNDERSTORMS ARE EXPECTED TO DEVELOP AROUND 18Z TODAY...WITH THE BEST CHANCE OF SHOWERS OVER THE SANGRES AND WET MTNS. LATEST NAM GUIDANCE HAS CLOSE TO 1000J OF CAPE WITH GENERALLY WEAK SHEAR OF 15-20 KTS THIS AFTERNOON. TSTMS WILL BE ON THE WEAKER SIDE THIS AFTERNOON...WITH ISOLATED HEAVY RAINFALL BEING THE PRIMARY THREAT. MODEL GUIDANCE SUGGESTS STEERING WINDS OUT OF THE NNW LATER THIS AFTERNOON...KEEPING MOST OF THE TSTMS ACTION CONFINED CLOSELY TO MTN AREAS. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO BE NEAR AVERAGE FOR THIS TIME OF YEAR. TONIGHT... ANY LINGERING ISOLATED TSRA WILL QUICKLY DIMINISH BETWEEN 03-06Z AS RADIATIVE PROCESSES BECOME DOMINATE. DIURNAL MOUNTAIN CIRCULATIONS LOOK TO BECOME DOMINATE...DIMINISHING THE CHANCES OF ANY STRATUS OR FOG FORMATION FOR THIS PERIOD. CLOUD COVER WILL DIMINISH HEADING INTO THE OVERNIGHT HOURS. -AL .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 323 AM MDT SAT JUN 27 2015 EXPECT AN INCREASE IN CONVECTION OVER THE EASTERN MOUNTAINS AND ADJACENT PLAINS SUN AS SHORT WAVE RIDES OVER THE CREST OF THE WESTERN UPPER RIDGE AND DIVES INTO THE HIGH PLAINS BY LATE SUN AFTERNOON. COLD FRONT ASSOCIATED WITH THE WAVE WILL ALSO DROP SOUTH THROUGH THE EASTERN PLAINS SUN...SWITCHING WINDS TO THE E-NE BY AFTERNOON AND PERHAPS AIDING IN TSRA DEVELOPMENT. STEERING CURRENTS STILL MAINTAIN A STRONG NORTHERLY COMPONENT...WHICH WILL AGAIN PREVENT STORMS FROM MOVING TOO FAR EAST OF I-25. WITH FRONT NOT ARRIVING UNTIL AFTERNOON...TEMPS ON THE PLAINS WILL BE A COUPLE DEGF WARMER THAN SAT...WHILE MOUNTAINS/VALLEYS REMAIN NEARLY UNCHANGED. BEST UPWARD MOTION SHIFTS QUICKLY SOUTH INTO NM SUN EVENING...LEADING TO RATHER RAPID CONVECTIVE DECAY AFTER SUNSET MOST LOCATIONS. ON MON...WHILE MOISTURE LEVELS REMAIN FAIRLY STEADY ACROSS THE REGION...STEERING CURRENTS BECOME EVEN MORE UNFAVORABLE FOR STORMS TO MOVE EASTWARD AWAY FROM THE MOUNTAINS...AS MID LEVEL WINDS TAKE ON A SLIGHT NE DIRECTION AS UPPER RIDGE WOBBLES EASTWARD. SUSPECT MOST TSRA WILL STAY WEST OF I-25 THROUGH THE DAY...ENDING QUICKLY IN THE EVENING WITH LACK OF FORCING. MAX TEMPS MON WILL AGAIN CHANGE VERY LITTLE OVER THE MOUNTAINS/VALLEYS...WITH SLIGHT COOLING OVER THE PLAINS IN THE WAKE OF SUNDAY`S COLD FRONT. TUE LOOKS LIKE ANOTHER RELATIVELY DOWN DAY FOR CONVECTION AS WESTERN RIDGE FLATTENS AND EXPANDS SLIGHTLY EASTWARD WITH RISING HEIGHTS/TEMPS ALOFT. STILL ENOUGH MOISTURE AROUND FOR THE USUAL CROP OF AFTERNOON/EARLY EVENING TSRA...AGAIN LIMITED TO MAINLY THE HIGHER TERRAIN. AFTER TUE...RIDGE RETREATS WESTWARD WITH UPPER FLOW BECOMING MORE NORTHWESTERLY THROUGH THE END OF THE WEEK. ENERGY DROPPING INTO THE DEEPENING TROUGH OVER THE UPPER MIDWEST WILL PUSH A COLD FRONT SOUTH THROUGH THE REGION WED...WITH PERHAPS ANOTHER REINFORCING SURGE BY THE END OF THE WEEK. MOIST EASTERLY UPSLOPE FLOW UNDER NORTHWEST FLOW ALOFT WILL MEAN AN INCREASE IN TSRA CHANCES FOR MUCH OF THE EASTERN MOUNTAINS AND PLAINS WED- SAT...WHILE LINGERING MOISTURE KEEPS AT LEAST ISOLATED CONVECTION GOING FARTHER WEST AS WELL. WITH HIGH SHIFTING WEST AND COOLER AIR FILTERING SOUTH...EXPECT TUE WILL BE THE HOTTEST DAY OF THE WEEK...WITH GRADUAL COOLING TREND ALL AREAS FROM WED INTO THE WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1110 AM MDT SAT JUN 27 2015 VFR CONDITIONS ARE EXPECTED ACROSS THE MAJORITY OF THE FORECAST AREA OVER THE NEXT 24 HRS...INCLUDING THE THREE MAIN TAF SITES OF KCOS...KPUB AND KALS. CONVECTION IS EXPECTED TO REMAIN CONFINED TO THE HIGHER TERRAIN THIS AFTN AND EVE...PROMPTING VCTS FOR KALS BETWEEN 21Z AND 04Z BUT STAYING CLEAR OF KCOS AND KPUB. MOORE && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...PETERSEN AVIATION...MOORE
AREA FORECAST DISCUSSION
NWS PUEBLO CO
403 AM MDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM MDT SAT JUN 27 2015 CURRENTLY... RADAR IMAGERY SHOWS SCT TSRA SHOWERS OVER THE FAR SRN EXTENT OF THE SANGRE DE CRISTO MTNS ASSOCIATED WITH A WEAK SHORTWAVE FEATURE LOCATED OVER SOUTHERN CO. SHOWERS ARE PROGGED TO CONTINUE TO MOVE SOUTH OVER THE NEXT FEW HOURS WITH ACTIVITY DECREASING INTO THE EARLY MORNING HOURS. TODAY... AN OMEGA BLOCK WILL REMAIN CENTERED OVER UTAH TODAY AND TONIGHT...MAINTAINING A PERIOD OF GENERALLY CALM WEATHER OVER MOST OF THE CWA. LATEST 07Z HRRR GUIDANCE CONTINUES TO SUPPORT THE DEVELOPMENT OF A STRATUS LAYER ALONG THE I-25 CORRIDOR...WITH THE BEST CHANCE OF DEVELOPMENT IN EL PASO COUNTY. GENERALLY WEAK SE UPSLOPE FLOW WILL AIDE IN STRATUS FORMATION...HOWEVER WINDS WILL TRANSITION TO A WESTERLY COMPONENT AROUND 14Z ALLOWING FOR THE LIFTING OF ANY STRATUS THAT DOES DEVELOP. DIURNALLY DRIVEN MTN THUNDERSTORMS ARE EXPECTED TO DEVELOP AROUND 18Z TODAY...WITH THE BEST CHANCE OF SHOWERS OVER THE SANGRES AND WET MTNS. LATEST NAM GUIDANCE HAS CLOSE TO 1000J OF CAPE WITH GENERALLY WEAK SHEAR OF 15-20 KTS THIS AFTERNOON. TSTMS WILL BE ON THE WEAKER SIDE THIS AFTERNOON...WITH ISOLATED HEAVY RAINFALL BEING THE PRIMARY THREAT. MODEL GUIDANCE SUGGESTS STEERING WINDS OUT OF THE NNW LATER THIS AFTERNOON...KEEPING MOST OF THE TSTMS ACTION CONFINED CLOSELY TO MTN AREAS. HIGH TEMPERATURES THIS AFTERNOON ARE EXPECTED TO BE NEAR AVERAGE FOR THIS TIME OF YEAR. TONIGHT... ANY LINGERING ISOLATED TSRA WILL QUICKLY DIMINISH BETWEEN 03-06Z AS RADIATIVE PROCESSES BECOME DOMINATE. DIURNAL MOUNTAIN CIRCULATIONS LOOK TO BECOME DOMINATE...DIMINISHING THE CHANCES OF ANY STRATUS OR FOG FORMATION FOR THIS PERIOD. CLOUD COVER WILL DIMINISH HEADING INTO THE OVERNIGHT HOURS. -AL .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 323 AM MDT SAT JUN 27 2015 EXPECT AN INCREASE IN CONVECTION OVER THE EASTERN MOUNTAINS AND ADJACENT PLAINS SUN AS SHORT WAVE RIDES OVER THE CREST OF THE WESTERN UPPER RIDGE AND DIVES INTO THE HIGH PLAINS BY LATE SUN AFTERNOON. COLD FRONT ASSOCIATED WITH THE WAVE WILL ALSO DROP SOUTH THROUGH THE EASTERN PLAINS SUN...SWITCHING WINDS TO THE E-NE BY AFTERNOON AND PERHAPS AIDING IN TSRA DEVELOPMENT. STEERING CURRENTS STILL MAINTAIN A STRONG NORTHERLY COMPONENT...WHICH WILL AGAIN PREVENT STORMS FROM MOVING TOO FAR EAST OF I-25. WITH FRONT NOT ARRIVING UNTIL AFTERNOON...TEMPS ON THE PLAINS WILL BE A COUPLE DEGF WARMER THAN SAT...WHILE MOUNTAINS/VALLEYS REMAIN NEARLY UNCHANGED. BEST UPWARD MOTION SHIFTS QUICKLY SOUTH INTO NM SUN EVENING...LEADING TO RATHER RAPID CONVECTIVE DECAY AFTER SUNSET MOST LOCATIONS. ON MON...WHILE MOISTURE LEVELS REMAIN FAIRLY STEADY ACROSS THE REGION...STEERING CURRENTS BECOME EVEN MORE UNFAVORABLE FOR STORMS TO MOVE EASTWARD AWAY FROM THE MOUNTAINS...AS MID LEVEL WINDS TAKE ON A SLIGHT NE DIRECTION AS UPPER RIDGE WOBBLES EASTWARD. SUSPECT MOST TSRA WILL STAY WEST OF I-25 THROUGH THE DAY...ENDING QUICKLY IN THE EVENING WITH LACK OF FORCING. MAX TEMPS MON WILL AGAIN CHANGE VERY LITTLE OVER THE MOUNTAINS/VALLEYS...WITH SLIGHT COOLING OVER THE PLAINS IN THE WAKE OF SUNDAY`S COLD FRONT. TUE LOOKS LIKE ANOTHER RELATIVELY DOWN DAY FOR CONVECTION AS WESTERN RIDGE FLATTENS AND EXPANDS SLIGHTLY EASTWARD WITH RISING HEIGHTS/TEMPS ALOFT. STILL ENOUGH MOISTURE AROUND FOR THE USUAL CROP OF AFTERNOON/EARLY EVENING TSRA...AGAIN LIMITED TO MAINLY THE HIGHER TERRAIN. AFTER TUE...RIDGE RETREATS WESTWARD WITH UPPER FLOW BECOMING MORE NORTHWESTERLY THROUGH THE END OF THE WEEK. ENERGY DROPPING INTO THE DEEPENING TROUGH OVER THE UPPER MIDWEST WILL PUSH A COLD FRONT SOUTH THROUGH THE REGION WED...WITH PERHAPS ANOTHER REINFORCING SURGE BY THE END OF THE WEEK. MOIST EASTERLY UPSLOPE FLOW UNDER NORTHWEST FLOW ALOFT WILL MEAN AN INCREASE IN TSRA CHANCES FOR MUCH OF THE EASTERN MOUNTAINS AND PLAINS WED- SAT...WHILE LINGERING MOISTURE KEEPS AT LEAST ISOLATED CONVECTION GOING FARTHER WEST AS WELL. WITH HIGH SHIFTING WEST AND COOLER AIR FILTERING SOUTH...EXPECT TUE WILL BE THE HOTTEST DAY OF THE WEEK...WITH GRADUAL COOLING TREND ALL AREAS FROM WED INTO THE WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 323 AM MDT SAT JUN 27 2015 SOME LOW STRATUS WILL BE FOUND IN THE VCNTY OF KCOS AND KPUB THIS MORNING AS MOIST SE UPSLOPE FLOW CONTINUES THIS MORNING. THESE CLOUDS WILL QUICKLY DISSIPATE AROUND 14Z AS WESTERLY FLOW TAKES OVER. VFR CONDITIONS ARE EXPECTED AT ALL THE TAF SITES THIS AFTERNOON. TSTMS REMAIN CONFINED TO MTN TERRAIN THIS AFTERNOON AND EVENING...AND WL LIKELY NOT AFFECT THE TAF SITES. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...28 LONG TERM...PETERSEN AVIATION...28
AREA FORECAST DISCUSSION
NWS ALBANY NY
123 AM EDT SAT JUN 27 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD OVER THE REGION TONIGHT...RESULTING IN A BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1245 AM EDT...WEAK AND SUBTLE LOW LEVEL CONVERGENCE WAS SETTING UP ACROSS THE MID HUDSON VALLEY AS CEILINGS AT KPOU CONTINUE TO SHOW SIGNS OF LOWERING. SOME SHOWERS WERE SEEN ON THE RADAR ACROSS NW NJ AND NE PA THAT THE NEW HRRR SUGGESTS MAY MIGRATE INTO OUR SOUTHERN ZONES. SO WE WILL EXPAND THE SLIGHT CHANCE POPS FOR THESE AREAS OVERNIGHT. THE REMAINDER OF THE REGION...CLOUDS WERE QUICKLY APPROACHING FROM THE WEST AS OHIO VALLEY STORM IS TAKING SHAPE. WE WILL ALSO INCREASE CLOUD COVER A BIT FROM WEST TO EAST. DUE TO THE INCREASE IN CLOUD COVER...WE WILL ADJUST LOWS SLIGHTLY UPWARD WILL BE IN THE UPPER 40S TO UPPER 50S. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... AN IMPRESSIVE STORM WILL DEVELOP ACROSS THE OHIO VALLEY AND IMPACT OUR REGION THIS WEEKEND... 12Z MODEL RUNS IN GENERAL AGREEMENT THAT THE CENTER OF THE SURFACE LOW WILL MOVE NORTHEASTWARD ACROSS THE EASTERN GREAT LAKES/WESTERN NY REGION SATURDAY AND SATURDAY NIGHT...THEN DOWN THE SAINT LAWRENCE VALLEY SUNDAY AND SUNDAY NIGHT. INITIALLY SATURDAY WILL START OUT DRY...BUT RAIN WILL BEGIN SPREADING ACROSS THE FORECAST AREA FROM SOUTHWEST TO NORTHEAST BY MID MORNING...WITH POPS FORECAST TO RISE AND REACH 100 PERCENT IN ALL AREAS BY EARLY SATURDAY EVENING. GENERALLY 100 PERCENT POPS FORECAST FOR THE REST OF SATURDAY NIGHT INTO VERY EARLY SUNDAY MORNING. THIS IS THE PERIOD WITH THE BEST POTENTIAL FOR HEAVY RAIN. HOWEVER...12Z MODEL RUNS HAVE REDUCED THE TOTAL RAINFALL AMOUNTS SOMEWHAT COMPARED TO EARLIER RUNS. EVEN WITH REDUCED RAINFALL FORECASTS...STILL EXPECT ABOUT AN INCH OR TWO OF RAIN ACROSS THE REGION WITH SOME LOCALLY HIGHER AMOUNTS. 12Z RUNS STILL SHOWING THE POTENTIAL FOR A SECONDARY SURFACE LOW TO DEVELOP TO THE EAST OF THE MAIN CENTER...BUT IT IS NOT NEARLY AS STRONG AS EARLIER RUNS HAD SHOWN...SO THE MODELS NOW SHOW A STRONG DRY SLOT ADVANCING NORTHWARD ACROSS THE REGION ON SUNDAY WITH THE WIDESPREAD PCPN AREA BREAKING UP INTO A SHOWERY PATTERN. POPS ARE FORECAST TO REMAIN HIGH THROUGH SUNDAY...BUT EXPECT THAT THERE WILL BE BREAKS IN THE PCPN...WITH EVEN A FEW BREAKS IN THE CLOUD COVER. THE DRY SLOT MAY ALSO RESULT IN THE ATMOSPHERE BECOMING SOMEWHAT UNSTABLE IF ENOUGH HEATING OCCURS...SO HAVE INCLUDED THE CHANCE OF TSTMS ON SUNDAY. THE SHOWERS WILL CONTINUE TO SLOWLY DECREASE SUNDAY NIGHT WITH DRY CONDITIONS EXPECTED BY SUNRISE MONDAY FOR MOST OF THE SOUTHEAST PART OF THE FORECAST AREA. BESIDES THE RAIN...THE OTHER FACTOR OF CONCERN WILL BE SOUTHEAST WINDS AHEAD OF THE OCCLUDED FRONT. THERE IS THE POTENTIAL FOR ADVISORY LEVEL WINDS SATURDAY NIGHT IN THOSE AREAS PRONE TO STRONG DOWNSLOPING WHEN THERE IS A STRONG SOUTHEAST GRADIENT (MAINLY THE SOUTHERN GREEN MOUNTAINS...THE BERKSHIRES AND THE NORTHERN AND CENTRAL TACONICS. WILL MONITOR LATER FORECASTS FOR THIS POTENTIAL. TEMPS WILL BE BELOW NORMAL THIS WEEKEND...ESPECIALLY THE DAYTIME HIGHS. HIGHS SATURDAY WILL BE IN THE 60S TO LOWER 70S. LOWS SATURDAY NIGHT 50 TO 60. HIGHS SUNDAY GENERALLY IN THE 60S TO MID 70S. LOWS SUNDAY NIGHT 50 TO 60. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE EXTENDED FORECAST BEGINS WITH A BRIEF PERIOD OF DRY WEATHER...AS A SHORT-WAVE RIDGE BUILDS IN OVER NY AND NEW ENGLAND ON MONDAY. SOME ISOLD-SCT INSTABILITY SHOWERS /AS THE COLD POOL ALOFT DRIFTS OVER NEW ENGLAND AND SE QUEBEC/ ARE POSSIBLE DURING THE AFTERNOON NORTH OF THE CAPITAL REGION/MOHAWK VALLEY ESPECIALLY OVER THE SRN DACKS...AND SRN GREENS. MOST OF THE FCST AREA SHOULD BE DRY...WITH MORE SUNSHINE FROM THE CAPITAL REGION SOUTH. TEMPS WILL STILL RUN A LITTLE BELOW NORMAL WITH H850 TEMPS IN THE +10C TO +12C RANGE DURING THE AFTERNOON. MAX TEMPS WILL BE IN THE M60S TO L70S OVER THE HILLS AND MTNS...AND MAINLY LOWER TO M70S IN THE VALLEYS /A FEW U70S IN THE MID HUDSON VALLEY/. CLOUDS BEGIN TO INCREASE FROM THE WEST MONDAY NIGHT...AS THE NEXT UPPER LEVEL TROUGH MOVES TOWARDS NY AND NEW ENGLAND. SOME WARM ADVECTION SHOWERS MAY GET CLOSE TO LOCATIONS WEST OF THE HUDSON RIVER VALLEY BTWN 06Z-12Z. LOWS WILL BE MAINLY IN THE 50S WITH A FEW LOWER 60S IN THE MID HUDSON VALLEY/NW CT. TUE-TUE NIGHT...A POTENTIAL ACTIVE WEATHER DAY...AS A WARM FRONT OR PREFRONTAL SFC TROUGH BASED ON THE GEFS/GFS/ECMWF IMPACTS THE FCST AREA WITH SHOWERS AND THUNDERSTORMS. THE SHORT-WAVE PIVOTING THROUGH THE NEUTRAL-NEGATIVELY TILTED LONG-WAVE TROUGH WILL ALSO HELP ENHANCE THE LIFT FOR THE SHOWERS AND THUNDERSTORMS. THE GFS CONTINUES TO HAVE SFC DEWPTS IN THE 60S WITH SOME L70S. NOT SURE ABOUT L70S THIS FAR OUT...BUT SBCAPES IN THE 1000-2000 J/KG RANGE ARE NOT OUT OF THE QUESTION...IF SUFFICIENT SFC DESTABILIZATION/HEATING OCCURS. THE GFS FOR TUE CONTINUES TO HAVE 0- 6 KM BULK SHEAR VALUES OF 35-40 KTS INDICATIVE OF SOME DEEP ORGANIZED CONVECTION. SOME STRONGER STORMS WILL BE POSSIBLE IN THE PM INTO THE EARLY EVENING...ESPECIALLY IF THERE IS ENOUGH SUNSHINE. THE GEFS HAVE PWATS RISE ABOUT 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AS SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. IT WILL BE MORE HUMID WITH HIGHS IN THE 70S TO L80S. THE SHOWERS AND THUNDERSTORMS SHOULD DIMINISH OVERNIGHT WITH LOWS IN THE U50S TO L60S. WEDNESDAY-WEDNESDAY NIGHT...THE UPPER LEVEL TROUGH CONTINUES TO BE OVER SE CANADA AND THE NORTHEAST WITH BROAD CYCLONIC FLOW. THE FIRST COLD FRONT SHOULD PASS SOUTH OF THE REGION EARLY IN THE DAY. ANOTHER SFC TROUGH OR SECONDARY COLD FRONT MAY MOVE THROUGH IN THE CYCLONIC FLOW FOR SCT SHOWERS AND ISOLD THUNDERSTORMS. HIGHS WILL BE IN THE U60S TO L70S OVER THE MTNS...AND MAINLY MID AND U70S OVER THE HILLS AND VALLEY LOCATIONS. THE MEDIUM RANGE GUIDANCE HAS TRENDED DRIER WED NIGHT WITH HIGH PRESSURE RIDGING IN FROM THE GREAT LAKES REGION. COOLER AND DRIER CONDITIONS WILL RETURN WITH LOWS IN THE 50S. THURSDAY INTO FRIDAY...TEMPERED THE POPS DOWN FURTHER THURSDAY TO NOTHING OR SLIGHT CHC...AS THE ECMWF/GFS INDICATES A BRIEF PERIOD OF DRY WX WITH THE UPPER TROUGH AXIS MOVING DOWNSTREAM OF ERN NY AND WRN NEW ENGLAND...AND A SFC RIDGE MOVING IN OVER THE REGION IN THE QUASI-ZONAL FLOW UPSTREAM. LOWS PRESSURE MAY MOVE NORTHEAST FROM THE MID ATLANTIC REGION THU NIGHT INTO FRIDAY WITH INCREASING CHANCES OF SHOWERS FROM SOUTH TO NORTH. TEMPS STILL LOOK A LITTLE BELOW NORMAL TO CLOSE THE EXTENDED. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR CONDITIONS ARE CURRENTLY IN PLACE AT ALL TERMINALS WITH VERY LIGHT OR CALM WINDS. HIGH CIRRUS CLOUDS...WELL AHEAD OF AN APPROACHING STORM OVER THE OHIO VALLEY...ARE MOVING INTO THE REGION AND WILL SHORTLY BECOME BKN-OVC AT ALL SITES AROUND 20-25 KFT. VFR CONDITIONS LOOK TO CONTINUE INTO SATURDAY MORNING. THE HIGH CLOUDS WILL CONTINUE TO THICKEN AND LOWER THROUGH THE MORNING HOURS...WITH CIGS LOWERING TO 10-15 KFT BY THE MID TO LATE MORNING HOURS. A STEADY RAINFALL WILL BE APPROACHING FROM CENTRAL NY/PENNSYLVANIA AND LOOKS TO REACH INTO THE TERMINALS BETWEEN 18Z- 21Z FROM SOUTH TO NORTH. INITIALLY...VSBY WILL LOWER TO 4-5SM WITHIN RAINFALL BUT CIGS WILL REMAIN AT VFR LEVELS AT 3500-5000 FT...ALTHOUGH THEY SHOULD GRADUALLY DROP INTO MVFR RANGE AS WELL. AS RAINFALL INTENSITY STARTS TO PICK UP TOWARDS EVENING...IFR CONDITIONS WILL OCCUR BEGINNING AROUND 23Z/SATURDAY-01Z/SUNDAY WITH VSBYS DOWN TO 1-2SM. CIGS WILL LOWER TO 1500-2500 FT...AND WILL EVENTUALLY DROP BELOW 1000 FT DURING SATURDAY NIGHT...WITH PERIODS OF MODERATE TO HEAVY RAIN POSSIBLE AS WELL. IN ADDITION...S-SE WINDS WILL INCREASE SAT MORNING TO 5-10 KTS. BY SAT AFTN INTO SAT EVENING...WINDS WILL BECOME E-NE AND INCREASE TO 10-15 KTS...ESP AT KPSF...AND THIS WILL CONTINUE THROUGH THE OVERNIGHT HOURS. SOME STRONGER GUSTS ARE POSSIBLE FOR KPSF WITH WINDS DOWNSLOPING OFF THE HIGHER ELEVATIONS. IN ADDITION...WILL HAVE TO MONITOR THE POTENTIAL FOR LLWS AS WELL...AS 2 KFT WINDS REACH 30-40 KTS FOR LATE SAT EVENING. OUTLOOK... SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY. DEFINITE RA. SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY. DEFINITE SHRA...TSRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. && .FIRE WEATHER... MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND AS A WIDESPREAD...SOAKING RAINFALL OCCURS ACROSS THE REGION SATURDAY AFTERNOON INTO SUNDAY. THE RH VALUES WILL RECOVER TO BETWEEN 75 AND 100 PERCENT TONIGHT AND REMAIN HIGH THROUGH THE WEEKEND. && .HYDROLOGY... EXCEPT FOR ISOLATED SHOWERS THIS EVENING...DRY WEATHER IS EXPECTED INTO SATURDAY MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON INTO EARLY SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION. RIGHT NOW...ONE TO TWO INCHES OF RAINFALL ARE POSSIBLE ACROSS THE HSA WITH SOME UPSLOPE AREAS GETTING A LITTLE MORE. THE TRACK AND RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR. 12Z MODEL RUNS HAVE GENERALLY DECREASED THE RAINFALL AMOUNTS BY A QUARTER TO HALF AN INCH COMPARED TO PREVIOUS RUNS. THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES TO THE CAUTION OR ALERT STAGES AT ONLY A COUPLE OF SITES AT THIS TIME. URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME. 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...GJM NEAR TERM...GJM/BGM/OKEEFE SHORT TERM...GJM LONG TERM...WASULA AVIATION...FRUGIS FIRE WEATHER...GJM/BGM/WASULA HYDROLOGY...GJM/BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1252 AM EDT SAT JUN 27 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD OVER THE REGION TONIGHT...RESULTING IN A BRIEF PERIOD OF FAIR AND DRY WEATHER. AN INTENSIFYING STORM OVER THE OHIO VALLEY WILL APPROACH ON SATURDAY...BRINGING PERIODS OF RAIN AND COOL CONDITIONS FOR THIS FIRST FULL WEEKEND OF SUMMER. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1245 AM EDT...WEAK AND SUBTLE LOW LEVEL CONVERGENCE WAS SETTING UP ACROSS THE MID HUDSON VALLEY AS CEILINGS AT KPOU CONTINUE TO SHOW SIGNS OF LOWERING. SOME SHOWERS WERE SEEN ON THE RADAR ACROSS NW NJ AND NE PA THAT THE NEW HRRR SUGGESTS MAY MIGRATE INTO OUR SOUTHERN ZONES. SO WE WILL EXPAND THE SLIGHT CHANCE POPS FOR THESE AREAS OVERNIGHT. THE REMAINDER OF THE REGION...CLOUDS WERE QUICKLY APPROACHING FROM THE WEST AS OHIO VALLEY STORM IS TAKING SHAPE. WE WILL ALSO INCREASE CLOUD COVER A BIT FROM WEST TO EAST. DUE TO THE INCREASE IN CLOUD COVER...WE WILL ADJUST LOWS SLIGHTLY UPWARD WILL BE IN THE UPPER 40S TO UPPER 50S. && .SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/... AN IMPRESSIVE STORM WILL DEVELOP ACROSS THE OHIO VALLEY AND IMPACT OUR REGION THIS WEEKEND... 12Z MODEL RUNS IN GENERAL AGREEMENT THAT THE CENTER OF THE SURFACE LOW WILL MOVE NORTHEASTWARD ACROSS THE EASTERN GREAT LAKES/WESTERN NY REGION SATURDAY AND SATURDAY NIGHT...THEN DOWN THE SAINT LAWRENCE VALLEY SUNDAY AND SUNDAY NIGHT. INITIALLY SATURDAY WILL START OUT DRY...BUT RAIN WILL BEGIN SPREADING ACROSS THE FORECAST AREA FROM SOUTHWEST TO NORTHEAST BY MID MORNING...WITH POPS FORECAST TO RISE AND REACH 100 PERCENT IN ALL AREAS BY EARLY SATURDAY EVENING. GENERALLY 100 PERCENT POPS FORECAST FOR THE REST OF SATURDAY NIGHT INTO VERY EARLY SUNDAY MORNING. THIS IS THE PERIOD WITH THE BEST POTENTIAL FOR HEAVY RAIN. HOWEVER...12Z MODEL RUNS HAVE REDUCED THE TOTAL RAINFALL AMOUNTS SOMEWHAT COMPARED TO EARLIER RUNS. EVEN WITH REDUCED RAINFALL FORECASTS...STILL EXPECT ABOUT AN INCH OR TWO OF RAIN ACROSS THE REGION WITH SOME LOCALLY HIGHER AMOUNTS. 12Z RUNS STILL SHOWING THE POTENTIAL FOR A SECONDARY SURFACE LOW TO DEVELOP TO THE EAST OF THE MAIN CENTER...BUT IT IS NOT NEARLY AS STRONG AS EARLIER RUNS HAD SHOWN...SO THE MODELS NOW SHOW A STRONG DRY SLOT ADVANCING NORTHWARD ACROSS THE REGION ON SUNDAY WITH THE WIDESPREAD PCPN AREA BREAKING UP INTO A SHOWERY PATTERN. POPS ARE FORECAST TO REMAIN HIGH THROUGH SUNDAY...BUT EXPECT THAT THERE WILL BE BREAKS IN THE PCPN...WITH EVEN A FEW BREAKS IN THE CLOUD COVER. THE DRY SLOT MAY ALSO RESULT IN THE ATMOSPHERE BECOMING SOMEWHAT UNSTABLE IF ENOUGH HEATING OCCURS...SO HAVE INCLUDED THE CHANCE OF TSTMS ON SUNDAY. THE SHOWERS WILL CONTINUE TO SLOWLY DECREASE SUNDAY NIGHT WITH DRY CONDITIONS EXPECTED BY SUNRISE MONDAY FOR MOST OF THE SOUTHEAST PART OF THE FORECAST AREA. BESIDES THE RAIN...THE OTHER FACTOR OF CONCERN WILL BE SOUTHEAST WINDS AHEAD OF THE OCCLUDED FRONT. THERE IS THE POTENTIAL FOR ADVISORY LEVEL WINDS SATURDAY NIGHT IN THOSE AREAS PRONE TO STRONG DOWNSLOPING WHEN THERE IS A STRONG SOUTHEAST GRADIENT (MAINLY THE SOUTHERN GREEN MOUNTAINS...THE BERKSHIRES AND THE NORTHERN AND CENTRAL TACONICS. WILL MONITOR LATER FORECASTS FOR THIS POTENTIAL. TEMPS WILL BE BELOW NORMAL THIS WEEKEND...ESPECIALLY THE DAYTIME HIGHS. HIGHS SATURDAY WILL BE IN THE 60S TO LOWER 70S. LOWS SATURDAY NIGHT 50 TO 60. HIGHS SUNDAY GENERALLY IN THE 60S TO MID 70S. LOWS SUNDAY NIGHT 50 TO 60. && .LONG TERM /MONDAY THROUGH FRIDAY/... THE EXTENDED FORECAST BEGINS WITH A BRIEF PERIOD OF DRY WEATHER...AS A SHORT-WAVE RIDGE BUILDS IN OVER NY AND NEW ENGLAND ON MONDAY. SOME ISOLD-SCT INSTABILITY SHOWERS /AS THE COLD POOL ALOFT DRIFTS OVER NEW ENGLAND AND SE QUEBEC/ ARE POSSIBLE DURING THE AFTERNOON NORTH OF THE CAPITAL REGION/MOHAWK VALLEY ESPECIALLY OVER THE SRN DACKS...AND SRN GREENS. MOST OF THE FCST AREA SHOULD BE DRY...WITH MORE SUNSHINE FROM THE CAPITAL REGION SOUTH. TEMPS WILL STILL RUN A LITTLE BELOW NORMAL WITH H850 TEMPS IN THE +10C TO +12C RANGE DURING THE AFTERNOON. MAX TEMPS WILL BE IN THE M60S TO L70S OVER THE HILLS AND MTNS...AND MAINLY LOWER TO M70S IN THE VALLEYS /A FEW U70S IN THE MID HUDSON VALLEY/. CLOUDS BEGIN TO INCREASE FROM THE WEST MONDAY NIGHT...AS THE NEXT UPPER LEVEL TROUGH MOVES TOWARDS NY AND NEW ENGLAND. SOME WARM ADVECTION SHOWERS MAY GET CLOSE TO LOCATIONS WEST OF THE HUDSON RIVER VALLEY BTWN 06Z-12Z. LOWS WILL BE MAINLY IN THE 50S WITH A FEW LOWER 60S IN THE MID HUDSON VALLEY/NW CT. TUE-TUE NIGHT...A POTENTIAL ACTIVE WEATHER DAY...AS A WARM FRONT OR PREFRONTAL SFC TROUGH BASED ON THE GEFS/GFS/ECMWF IMPACTS THE FCST AREA WITH SHOWERS AND THUNDERSTORMS. THE SHORT-WAVE PIVOTING THROUGH THE NEUTRAL-NEGATIVELY TILTED LONG-WAVE TROUGH WILL ALSO HELP ENHANCE THE LIFT FOR THE SHOWERS AND THUNDERSTORMS. THE GFS CONTINUES TO HAVE SFC DEWPTS IN THE 60S WITH SOME L70S. NOT SURE ABOUT L70S THIS FAR OUT...BUT SBCAPES IN THE 1000-2000 J/KG RANGE ARE NOT OUT OF THE QUESTION...IF SUFFICIENT SFC DESTABILIZATION/HEATING OCCURS. THE GFS FOR TUE CONTINUES TO HAVE 0- 6 KM BULK SHEAR VALUES OF 35-40 KTS INDICATIVE OF SOME DEEP ORGANIZED CONVECTION. SOME STRONGER STORMS WILL BE POSSIBLE IN THE PM INTO THE EARLY EVENING...ESPECIALLY IF THERE IS ENOUGH SUNSHINE. THE GEFS HAVE PWATS RISE ABOUT 1-2 STANDARD DEVIATIONS ABOVE NORMAL...AS SOME LOCALLY HEAVY RAINFALL WILL BE POSSIBLE. IT WILL BE MORE HUMID WITH HIGHS IN THE 70S TO L80S. THE SHOWERS AND THUNDERSTORMS SHOULD DIMINISH OVERNIGHT WITH LOWS IN THE U50S TO L60S. WEDNESDAY-WEDNESDAY NIGHT...THE UPPER LEVEL TROUGH CONTINUES TO BE OVER SE CANADA AND THE NORTHEAST WITH BROAD CYCLONIC FLOW. THE FIRST COLD FRONT SHOULD PASS SOUTH OF THE REGION EARLY IN THE DAY. ANOTHER SFC TROUGH OR SECONDARY COLD FRONT MAY MOVE THROUGH IN THE CYCLONIC FLOW FOR SCT SHOWERS AND ISOLD THUNDERSTORMS. HIGHS WILL BE IN THE U60S TO L70S OVER THE MTNS...AND MAINLY MID AND U70S OVER THE HILLS AND VALLEY LOCATIONS. THE MEDIUM RANGE GUIDANCE HAS TRENDED DRIER WED NIGHT WITH HIGH PRESSURE RIDGING IN FROM THE GREAT LAKES REGION. COOLER AND DRIER CONDITIONS WILL RETURN WITH LOWS IN THE 50S. THURSDAY INTO FRIDAY...TEMPERED THE POPS DOWN FURTHER THURSDAY TO NOTHING OR SLIGHT CHC...AS THE ECMWF/GFS INDICATES A BRIEF PERIOD OF DRY WX WITH THE UPPER TROUGH AXIS MOVING DOWNSTREAM OF ERN NY AND WRN NEW ENGLAND...AND A SFC RIDGE MOVING IN OVER THE REGION IN THE QUASI-ZONAL FLOW UPSTREAM. LOWS PRESSURE MAY MOVE NORTHEAST FROM THE MID ATLANTIC REGION THU NIGHT INTO FRIDAY WITH INCREASING CHANCES OF SHOWERS FROM SOUTH TO NORTH. TEMPS STILL LOOK A LITTLE BELOW NORMAL TO CLOSE THE EXTENDED. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... VFR CONDITIONS IN PLACE THROUGH MOST OF THE PERIOD. IN THE LAST FEW HOURS OF THE FORECAST...MVFR CONDITIONS WILL OVERSPREAD THE REGION AS A STEADY RAIN BEGINS. SOME POTENTIAL FOR LLWS AT KPOU NEAR THE END OF THE FORECAST PERIOD. HOWEVER...AT THIS TIME...STILL TOO UNCERTAIN TO INCLUDE. THE POTENTIAL FOR LLWS AT ALL OTHER FORECAST TERMINALS EXITS AS WELL JUST BEYOND THE FORECAST PERIOD. OUTLOOK... SATURDAY NIGHT: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE RA...TSRA. SUNDAY: HIGH OPERATIONAL IMPACT. BREEZY DEFINITE SHRA...TSRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. BREEZY CHANCE OF SHRA. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. && .FIRE WEATHER... MINIMAL TO LOW FIRE WEATHER RELATED CONCERNS THROUGH THE WEEKEND AS A WIDESPREAD...SOAKING RAINFALL OCCURS ACROSS THE REGION SATURDAY AFTERNOON INTO SUNDAY. THE RH VALUES WILL RECOVER TO BETWEEN 75 AND 100 PERCENT TONIGHT AND REMAIN HIGH THROUGH THE WEEKEND. && .HYDROLOGY... EXCEPT FOR ISOLATED SHOWERS THIS EVENING...DRY WEATHER IS EXPECTED INTO SATURDAY MORNING BEFORE A STRONG LOW PRESSURE SYSTEM DEVELOPS NEAR THE OHIO VALLEY AND MOVES TOWARDS THE EASTERN GREAT LAKES REGION. PERIODS OF MODERATE TO HEAVY RAINFALL ARE POSSIBLE LATE SATURDAY AFTERNOON INTO EARLY SUNDAY...DEPENDING ON THE EVENTUAL TRACK AND EVOLUTION OF LOW PRESSURE DEVELOPING ACROSS THE OHIO VALLEY REGION. RIGHT NOW...ONE TO TWO INCHES OF RAINFALL ARE POSSIBLE ACROSS THE HSA WITH SOME UPSLOPE AREAS GETTING A LITTLE MORE. THE TRACK AND RAINFALL DURATION WILL DETERMINE WHERE THE HIGHER AMOUNTS WILL OCCUR. 12Z MODEL RUNS HAVE GENERALLY DECREASED THE RAINFALL AMOUNTS BY A QUARTER TO HALF AN INCH COMPARED TO PREVIOUS RUNS. THE LATEST MMEFS GUIDANCE CONTINUES TO SUGGEST WITHIN BANK RISES TO THE CAUTION OR ALERT STAGES AT ONLY A COUPLE OF SITES AT THIS TIME. URBAN AND SMALL STREAM CONCERNS ACROSS THE HSA WILL HAVE TO BE MONITORED...AND WILL MENTION IN THE HWO. ALSO...IF CONFIDENCE INCREASES FOR THE POTENTIAL OF WIDESPREAD MINOR FLOODING...THEN A FLOOD WATCH MAY BE NEEDED FOR PORTIONS OF THE HSA LATER IN TIME. 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...GJM NEAR TERM...GJM/BGM/OKEEFE SHORT TERM...GJM LONG TERM...WASULA AVIATION...OKEEFE FIRE WEATHER...GJM/BGM/WASULA HYDROLOGY...GJM/BGM/WASULA
AREA FORECAST DISCUSSION
NWS LINCOLN IL
257 PM CDT SAT JUN 27 2015 .SHORT TERM...(TONIGHT) ISSUED AT 253 PM CDT SAT JUN 27 2015 ISOLATED SHOWERS AND POSSIBLE THUNDERSTORMS WEST OF A GALESBURG TO BEARDSTOWN TO JACKSONVILLE LINE AT MID AFTERNOON FROM VERY WEAK SHORT WAVE MOVING SOUTH NEAR MS RIVER VALLEY WILL DISSIPATE BY 00Z/7 PM LEAVING DRY CONDITIONS ACROSS CWA TONIGHT. DIRUNALLY DRIVEN SCATTERED CUMULUS CLOUDS TO DISSIPATE AT SUNSET AS WELL LEAVING FAIR SKIES TONIGHT ACROSS CENTRAL/SE IL. STRONGER NORTHERN STREAM SHORT WAVE ALONG THE SOUTHERN ONTARIO AND MANITOBA PROVINCE LINE WITH CONVECTION AS FAR SOUTH AS NORTHERN MN AND EASTERN ND WILL DIVE SE ACROSS MN/IA BY DAWN SUNDAY AND INCREASE CLOUDS LATER TONIGHT OVER IL RIVER VALLEY...MAINLY NW OF IL RIVER. ANY CONVECTION FROM THIS SYSTEM SHOULD STAY NW OF CWA THROUGH AT LEAST 12Z/7 AM SUNDAY. WEAK SURFACE HIGH PRESSURE RIDGE OF 1017 MB OVER THE MO VALLEY TO DRIFT OVER IL OVERNIGHT. SO BREEZY NORTH WINDS WITH GUSTS 15-25 MPH SHOULD DIMINISH LIGHT AND VARIABLE LATER THIS EVENING. DEWPOINTS HAVE SLIPPED INTO THE MID 50S TO NEAR 60F AT MID AFTERNOON AND THIS SHOULD BE WHERE LOWS REACH CLOSE TO OVERNIGHT. LOWS IN MID 50S OVER EASTERN IL AND UPPER 50S OVER THE IL RIVER VALLEY. && .LONG TERM...(SUNDAY THROUGH SATURDAY) ISSUED AT 253 PM CDT SAT JUN 27 2015 MAIN CHALLENGE WILL BE TIMING OF INDIVIDUAL SHORTWAVES AND ASSOCIATED PRECIPITATION CHANCES IN THE NORTHWEST FLOW ALOFT OVER THE EASTERN U.S. AS A RATHER AMPLIFIED PATTERN TAKES HOLD ACROSS THE AREA THRU THE WEEK. FIRST OF THE UPPER WAVES WAS TRACKING SSE ACROSS THE NORTHERN PLAINS THIS AFTERNOON AND WILL BRING AN INCREASING CHANCE FOR SHOWERS AND STORMS BACK INTO THE REGION SUNDAY AFTERNOON AND NIGHT. MIXED LAYER CAPES AROUND 1500 J/KG BY AFTERNOON ACROSS THE WEST...HOWEVER...STRONGER DEEP LAYER FLOW REMAINS JUST TO OUR WEST INTO THE EVENING HOURS WITH MARGINAL LAPSE RATES...DEPENDING ON WHICH MODEL YOU LOOK AT. THE NAM HAS SLOWED THE ONSET OF THE PRECIP AND IS KEEPING THE DEEP LAYER SHEAR AND BETTER INSTABILITY JUST TO OUR WEST. STILL COULD SEE STRONG WIND GUSTS WITH SOME OF THE MORE ORGANIZED STORMS TOMORROW AFTERNOON INTO THE EVENING AS THE UPPER WAVE TRACKS ACROSS OUR AREA. DUE TO THE PROGRESSIVE NATURE OF THE SYSTEM...IT APPEARS QPF VALUES WILL BE HELD IN CHECK WITH MOST AREAS SEEING A QUARTER TO ONE HALF INCH AMOUNTS LATE SUNDAY AFTERNOON INTO THE OVERNIGHT HOURS. THE SHORTWAVE WILL SHIFT OFF TO OUR EAST BY MONDAY MORNING WITH THE HIGHER POPS OVER THE EAST. STILL ENOUGH COLD AIR ALOFT ASSOCIATED WITH THE DEPARTING WAVE TO KEEP AT LEAST LOW CHANCE POPS GOING DURING THE AFTERNOON. POPS ARE IN THE SLIGHT CHANCE RANGE MONDAY NIGHT IN THE WAKE OF THE SHORTWAVE WITH LOW POPS HOLDING INTO TUESDAY BEFORE THE NEXT SHORTWAVE DROPS INTO THE REGION FOR MAINLY TUESDAY NIGHT. IF THE SOUTHWARD TREND IN THE MODELS CONTINUES...THE HIGHER THREAT FOR SHOWERS AND STORMS WOULD BE OVER OUR SOUTHERN AREAS...BUT FOR NOW... WITH SOME SPREAD IN THE MODEL SOLUTIONS FOR THAT TIME FRAME...WILL KEEP THE 30-40 POPS GOING TUESDAY NIGHT INTO WEDNESDAY. ANOTHER FAST MOVING WAVE EMBEDDED IN THE NORTHWEST FLOW WILL APPROACH THE AREA LATE WEDNESDAY/WEDNESDAY NIGHT WITH MORE ORGANIZED SHOWER AND THUNDERSTORM CHANCES ADVERTISED OFF THE LATEST ECMWF...WHILE THE 12Z GFS AND GEM GLOBAL SOLUTIONS NOT SHOWING MUCH REFLECTION QPF-WISE FROM THAT SHORTWAVE. PATTERN NOT EXPECTED TO MAKE MUCH OF A CHANGE UNTIL LATE NEXT WEEK MEANING THE DAILY THREAT FOR SCATTERED SHOWERS AND STORMS WILL CONTINUE INTO THE END OF THIS FORECAST PERIOD. THE LATEST ECMWF DOES OFFER SOME HOPE IN THE EXTENDED PERIOD AS IT SHIFTS THE STRONGER FLOW FURTHER NORTH AS AN UPPER LEVEL RIDGE EXPANDS NORTHWARD INTO THE CENTRAL PLAINS AND MIDWEST NEXT WEEKEND. THIS WOULD SHIFT THE BETTER CHANCES FOR SHOWERS AND STORMS FURTHER NORTH AND BRING SOME VERY WARM TEMPS BACK INTO THE AREA. HOWEVER...WITH AS MUCH WATER AS THERE IS IN THE SOIL OVER A LARGE PORTION OF THE CENTRAL U.S...IT SEEMS HARD TO BUY THE IDEA OF ANY PERSISTENT RIDGING OCCURRING ACROSS THE MIDDLE OF THE COUNTRY. IT`S NOT THE FIRST TIME THIS MODEL HAS TRIED TO AMPLIFY THE RIDGE OVER THE CENTER OF THE NATION...ONLY TO HAVE PERSISTENT CONVECTIVE ACTIVITY ACROSS THE NORTH-CENTRAL PLAINS KEEP THE PATTERN MUCH LESS AMPLIFIED WITH THE STRONGER FLOW DISPLACED FURTHER SOUTH THAN FORECAST. WE CAN ONLY HOPE WE SEE AT LEAST A TEMPORARY SHIFT IN THE PATTERN HEADING INTO THE SECOND WEEK OF JULY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1259 PM CDT SAT JUN 27 2015 VFR CONDITIONS ARE EXPECTED TO CONTINUE ACROSS THE CENTRAL IL AIRPORTS NEXT 24 HOURS THROUGH 18Z/1 PM SUNDAY. SCATTERED CUMULUS CLOUDS WITH BASES OF 3-5K FT WILL OCCUR THIS AFTERNOON WHILE BROKEN CEILINGS MORE CONFINED TO AREAS WEST OF PIA/SPI AND SOUTH OF I-72. ISOLATED SHOWERS AND THUNDERSTORMS THAT DEVELOP DURING MID/LATE AFTERNOON TO STAY WEST OF PIA/SPI PER HRRR AND RAP13 MODELS. THESE DIURNALLY ENHANCED CUMULUS CLOUDS TO DISSIPATE AT SUNSET LEAVING FAIR SKIES TONIGHT WITH JUST SCATTERED CIRRUS CLOUDS. SCATTERED CUMULUS CLOUDS TO APPEAR AGAIN BY 15Z/SUNDAY THOUGH ANY SHOWERS AND THUNDERSTORMS WILL NOT DEVELOP UNTIL AFTER 18Z/SUNDAY FROM I-55 NW. BREEZY NORTH WINDS 10-15 KTS AND GUSTS 16-23 KTS THIS AFTERNOON TO DIMINISH LIGHT AND VARIABLE BY SUNSET AS WEAK HIGH PRESSURE RIDGE SETTLES OVER IL. WINDS BECOME SW AT 5-9 KTS AFTER 14Z/SUNDAY AS WEAK SURFACE RIDGE PASSES EAST OF IL AND SHORT WAVE OVER NORTHERN PLAINS MOVES INTO THE UPPER MS RIVER VALLEY SUNDAY MORNING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...07 LONG TERM...SMITH AVIATION...07
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1259 PM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1045 AM CDT SAT JUN 27 2015 FORECAST GENERALLY LOOKS GOOD TODAY AND JUST SOME MINOR TWEAKS TO HAVE THE SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS DURING MID/LATE AFTERNOON A BIT FURTHER WEST...WEST OF PEORIA AND SPRINGFIELD. RAP13 AND HRRR MODELS SHOWING SOME QPF THIS AFTERNOON BETWEEN 18Z-23Z FROM GALESBURG TO JACKSONVILLE WEST AND ALSO EAST OF IL OVER INDIANA. A FEW BROKEN CUMULUS CLOUD CEILINGS BETWEEN 2-5K FT SE OF A CHAMPAIGN TO TAYLORVILLE LINE LATE THIS MORNING. SCATTERED CUMULUS CLOUDS ALSO TO APPEAR IN WESTERN IL BY THIS AFTERNOON. PARTLY TO MOSTLY SUNNY DAY OVERALL AND HIGHS IN THE UPPER 70S. MORE COMFORTABLE DEWPOINTS IN THE UPPER 50S TO NEAR 60F WITH NORTH BREEZES 10-15 MPH AND GUSTS 15-25 MPH ESPECIALLY IN EASTERN IL. && .SHORT TERM...(TODAY) ISSUED AT 311 AM CDT SAT JUN 27 2015 LOW PRESSURE AREA AND ASSOCIATED CLOUD COVER CONTINUES TO MOVE EAST AWAY FROM THE AREA. HOWEVER...CYCLONIC FLOW WILL CONTINUE OVER THE CWA TODAY. ISOLATED SHOWERS WILL BE POSSIBLE IN THE EXTREME EAST EARLY THIS MORNING AS THE SYSTEM PULLS AWAY. THEN UNDER MOSTLY SUNNY SKIES A COUPLE OF SHORT-RANGE HIGH RES MODELS ARE DEVELOPING SOME ISOLATED TO SCATTERED PCPN OVER PARTS OF EASTERN IA AND EASTERN MO. LOOKS LIKE THIS WILL INCLUDE WESTERN ILLINOIS AS WELL. DEPENDING ON DEGREE OF INSTABILITY BY THIS AFTERNOON...ISOLATED THUNDERSTORMS WILL BE POSSIBLE. SO HAVE ADDED THIS TO THE POP/WX GRIDS FOR THIS AFTERNOON IN MAINLY WESTERN PARTS OF THE CWA. WINDS WILL BE NORTHWESTERLY TODAY WITH GUSTS TO AROUND 20 MPH. DAYTIME HIGHS SHOULD BE WARMER THAN YESTERDAY GIVEN THERE WILL BE LOTS MORE SUNSHINE. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 311 AM CDT SAT JUN 27 2015 COOLER TEMPS FOR TONIGHT...BUT WARMING BACK UP TO JUST BELOW NORMAL MAX TEMPS OVERALL AS A SOUTHERLY COMPONENT COMES BACK TO THE SFC WINDS AND WARM ADVECTION BEGINS AGAIN. ANY SIGNIFICANT WARM UP IS TEMPERED BY ANOTHER APPROACHING SHORT WAVE FROM THE NW MOVING THROUGH AND BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS FOR SUN AFTERNOON AND OVERNIGHT INTO MONDAY. SOME TIMING DIFFERENCES WITH THE MORNING AND MUCH OF THE EARLY AFTERNOON DRY FOR THE ECMWF, AND THE GFS FAR MORE AGGRESSIVE WITH THE ONSET OF THE PRECIP. THESE DIFFERENCES WILL ALSO BE THE DRIVING FACTOR IN THE RISK FOR SEVERE WEATHER SUN EVENING/NIGHT WITH TIMING OF SYSTEM WITH MAX HEATING/INSTABILITY IN THE AFTERNOON. DETAILS STILL NOT IN FOCUS AND SPC HAS OPTED TO LEAVE A SMALL CHUNK OF CENTRAL ILLINOIS JUST IN A MARGINAL RISK FOR NOW. BEYOND SUNDAY AND INTO THE WORKWEEK...MON NIGHT/TUES HAS SEVERAL DIFFERENT SOLUTIONS WITH THE SLOW EXIT OF THE WAVE OVER THE REGION. WEAK NWRLY FLOW SETS UP AGAIN MIDWEEK AND A SERIES OF SHORTWAVES KEEPING POPS IN THE FORECAST IN THE EXTENDED AND A MESSY SUMMER PATTERN REMAINS IN PLACE WITH SEASONABLE/SLIGHTLY BELOW NORMAL HIGHS AND PLENTY OF RAIN CHANCES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1259 PM CDT SAT JUN 27 2015 VFR CONDITIONS ARE EXPECTED TO CONTINUE ACROSS THE CENTRAL IL AIRPORTS NEXT 24 HOURS THROUGH 18Z/1 PM SUNDAY. SCATTERED CUMULUS CLOUDS WITH BASES OF 3-5K FT WILL OCCUR THIS AFTERNOON WHILE BROKEN CEILINGS MORE CONFINED TO AREAS WEST OF PIA/SPI AND SOUTH OF I-72. ISOLATED SHOWERS AND THUNDERSTORMS THAT DEVELOP DURING MID/LATE AFTERNOON TO STAY WEST OF PIA/SPI PER HRRR AND RAP13 MODELS. THESE DIURNALLY ENHANCED CUMULUS CLOUDS TO DISSIPATE AT SUNSET LEAVING FAIR SKIES TONIGHT WITH JUST SCATTERED CIRRUS CLOUDS. SCATTERED CUMULUS CLOUDS TO APPEAR AGAIN BY 15Z/SUNDAY THOUGH ANY SHOWERS AND THUNDERSTORMS WILL NOT DEVELOP UNTIL AFTER 18Z/SUNDAY FROM I-55 NW. BREEZY NORTH WINDS 10-15 KTS AND GUSTS 16-23 KTS THIS AFTERNOON TO DIMINISH LIGHT AND VARIABLE BY SUNSET AS WEAK HIGH PRESSURE RIDGE SETTLES OVER IL. WINDS BECOME SW AT 5-9 KTS AFTER 14Z/SUNDAY AS WEAK SURFACE RIDGE PASSES EAST OF IL AND SHORT WAVE OVER NORTHERN PLAINS MOVES INTO THE UPPER MS RIVER VALLEY SUNDAY MORNING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...07 SHORT TERM...AUTEN LONG TERM...HJS AVIATION...07
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1045 AM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1045 AM CDT SAT JUN 27 2015 FORECAST GENERALLY LOOKS GOOD TODAY AND JUST SOME MINOR TWEAKS TO HAVE THE SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS DURING MID/LATE AFTERNOON A BIT FURTHER WEST...WEST OF PEORIA AND SPRINGFIELD. RAP13 AND HRRR MODELS SHOWING SOME QPF THIS AFTERNOON BETWEEN 18Z-23Z FROM GALESBURG TO JACKSONVILLE WEST AND ALSO EAST OF IL OVER INDIANA. A FEW BROKEN CUMULUS CLOUD CEILINGS BETWEEN 2-5K FT SE OF A CHAMPAIGN TO TAYLORVILLE LINE LATE THIS MORNING. SCATTERED CUMULUS CLOUDS ALSO TO APPEAR IN WESTERN IL BY THIS AFTERNOON. PARTLY TO MOSTLY SUNNY DAY OVERALL AND HIGHS IN THE UPPER 70S. MORE COMFORTABLE DEWPOINTS IN THE UPPER 50S TO NEAR 60F WITH NORTH BREEZES 10-15 MPH AND GUSTS 15-25 MPH ESPECIALLY IN EASTERN IL. && .SHORT TERM...(TODAY) ISSUED AT 311 AM CDT SAT JUN 27 2015 LOW PRESSURE AREA AND ASSOCIATED CLOUD COVER CONTINUES TO MOVE EAST AWAY FROM THE AREA. HOWEVER...CYCLONIC FLOW WILL CONTINUE OVER THE CWA TODAY. ISOLATED SHOWERS WILL BE POSSIBLE IN THE EXTREME EAST EARLY THIS MORNING AS THE SYSTEM PULLS AWAY. THEN UNDER MOSTLY SUNNY SKIES A COUPLE OF SHORT-RANGE HIGH RES MODELS ARE DEVELOPING SOME ISOLATED TO SCATTERED PCPN OVER PARTS OF EASTERN IA AND EASTERN MO. LOOKS LIKE THIS WILL INCLUDE WESTERN ILLINOIS AS WELL. DEPENDING ON DEGREE OF INSTABILITY BY THIS AFTERNOON...ISOLATED THUNDERSTORMS WILL BE POSSIBLE. SO HAVE ADDED THIS TO THE POP/WX GRIDS FOR THIS AFTERNOON IN MAINLY WESTERN PARTS OF THE CWA. WINDS WILL BE NORTHWESTERLY TODAY WITH GUSTS TO AROUND 20 MPH. DAYTIME HIGHS SHOULD BE WARMER THAN YESTERDAY GIVEN THERE WILL BE LOTS MORE SUNSHINE. .LONG TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 311 AM CDT SAT JUN 27 2015 COOLER TEMPS FOR TONIGHT...BUT WARMING BACK UP TO JUST BELOW NORMAL MAX TEMPS OVERALL AS A SOUTHERLY COMPONENT COMES BACK TO THE SFC WINDS AND WARM ADVECTION BEGINS AGAIN. ANY SIGNIFICANT WARM UP IS TEMPERED BY ANOTHER APPROACHING SHORT WAVE FROM THE NW MOVING THROUGH AND BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS FOR SUN AFTERNOON AND OVERNIGHT INTO MONDAY. SOME TIMING DIFFERENCES WITH THE MORNING AND MUCH OF THE EARLY AFTERNOON DRY FOR THE ECMWF, AND THE GFS FAR MORE AGGRESSIVE WITH THE ONSET OF THE PRECIP. THESE DIFFERENCES WILL ALSO BE THE DRIVING FACTOR IN THE RISK FOR SEVERE WEATHER SUN EVENING/NIGHT WITH TIMING OF SYSTEM WITH MAX HEATING/INSTABILITY IN THE AFTERNOON. DETAILS STILL NOT IN FOCUS AND SPC HAS OPTED TO LEAVE A SMALL CHUNK OF CENTRAL ILLINOIS JUST IN A MARGINAL RISK FOR NOW. BEYOND SUNDAY AND INTO THE WORKWEEK...MON NIGHT/TUES HAS SEVERAL DIFFERENT SOLUTIONS WITH THE SLOW EXIT OF THE WAVE OVER THE REGION. WEAK NWRLY FLOW SETS UP AGAIN MIDWEEK AND A SERIES OF SHORTWAVES KEEPING POPS IN THE FORECAST IN THE EXTENDED AND A MESSY SUMMER PATTERN REMAINS IN PLACE WITH SEASONABLE/SLIGHTLY BELOW NORMAL HIGHS AND PLENTY OF RAIN CHANCES. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 631 AM CDT SAT JUN 27 2015 MOSTLY SCATTERED MID CLOUDS OVER THE SITES THIS MORNING...EXCEPT AT BMI WHICH HAS BROKEN MVFR CIGS AT 2.5KFT. THIS WILL NOT LAST LONG AND EXPECTING ONLY SCATTERED CLOUDS HERE TOO. SOME LIGHT FOG IS ALSO PRESENT ALL PIA/SPI AND BMI. DEC AND CMI DO NOT HAVE FOG AT THIS TIME...BUT COULD THIS COMING HOUR...SO HAVE INCLUDED A TEMPO GROUP TO COVER...AND HAVE IT AT ALL SITES. EXPECTING SCATTERED CU TO DEVELOP LATER THIS MORNING IN CYCLONIC FLOW AND LOTS OF LOW LEVEL MOISTURE. A WEAK DISTURBANCE WILL DROP INTO WESTERN IL FOR THIS AFTERNOON WITH ISOLATED SHOWERS AND STORMS. CHANCES ARE LOW ENOUGH THAT I DID NOT INCLUDE IN THE 12Z TAFS. DIURNALLY CLOUDS WILL CLEAR OUT THIS EVENING. WINDS WILL BE NORTHERLY THROUGH MOST OF THE PERIOD AROUND 10-15KTS BUT THEN DIMINISH THIS EVENING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...07 SHORT TERM...AUTEN LONG TERM...HJS AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS DES MOINES IA
702 PM CDT SUN JUN 28 2015 .SHORT TERM /TONIGHT/... ISSUED AT 329 PM CDT SUN JUN 28 2015 MAIN CONCERNS SHORT TERM CONTINUE TO BE THE LOW OVER CENTRAL IOWA COMBINED WITH AN UPPER LEVEL VORT MAX OVER IOWA DIGGING SOUTH. WE REMAIN RATHER UNSTABLE WITH MLCAPE 1000-1500J/KG AND SBCAPE OF 2000 TO 2500 J/KG ALONG AN AXIS NEAR AND JUST BEHIND THE TROUGH AT 20Z. SFC CONVERGENCE IS RATHER MEAGER ALONG WITH BULK SHEAR VALUES JUST REACHING 30 TO 35 KTS AT THIS TIME. SOME WEAK CELLS HAVE DEVELOPED FROM NEAR AND EAST OF THE TROUGH AXIS THIS HOUR. EXPECT THIS ACTIVITY TO EXPAND IN COVERAGE THIS AFTERNOON AS THE SYSTEM TRACKS SOUTHEAST. WILL CONTINUE SVR WORDING IN SOUTHEAST/EAST ZONES FOR THE AFTERNOON...THOUGH COVERAGE MAY REMAIN SCT THROUGH 00Z. LCL HEIGHTS EAST OF I35 REMAIN AT 750M (~2450 FT) AND LOW LEVEL CAPE HAS INCREASED TO 100-150 J/KG ALONG THE TROUGH AXIS...SO WILL NEED TO MONITOR ANY STORMS FOR POTENTIAL BRIEF FUNNEL. AS THE SYSTEM PULLS SOUTHEAST THIS EVENING...DIURNAL HEATING WILL DIMINISH AND STORMS WILL DISSIPATE AFTER 01-02Z. HRRR MODEL CONTINUES TO BUBBLE UP ACTIVITY THROUGH THIS TIME. 4KM WRF ALSO SUGGESTS SOME ACTIVITY OVER SOUTHEAST MN MAY EXPAND INTO NORTHEAST IOWA BETWEEN 21 AND 00Z AS WELL. WITH PASSAGE OF THE BOUNDARY...DEW POINTS DROP TO THE UPPER 50S TO LOWER 60S...SO LOWS WILL COOL TO THE LOWER TO MID 60S BY MORNING. PATCHY FOG MAY DEVELOP IN THE CEDAR RIVER VALLEY TOWARD MORNING. .LONG TERM /MONDAY THROUGH SUNDAY/... ISSUED AT 329 PM CDT SUN JUN 28 2015 THERE HAS BEEN LITTLE CHANGE IN FORECAST THINKING FROM PREVIOUS SHIFTS. IOWA WILL REMAIN BENEATH NORTHWESTERLY FLOW ALOFT THROUGH THE END OF THE WEEK...KEEPING TEMPERATURES A LITTLE BELOW SEASONAL NORMALS AND LESSENING THE OVERALL SEVERE WEATHER THREAT. EVEN SO...THINGS WILL REMAIN FAIRLY ACTIVE AS A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH THIS FLOW WILL RESULT IN PERIODIC CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS OUR FORECAST AREA. THE FIRST SUCH OPPORTUNITY COME LATE ON MONDAY AS A SUBTLE IMPULSE PUSHES AN ATTENDANT WEAK SURFACE TROUGH FROM MINNESOTA DOWN ACROSS IOWA. DESPITE A RELATIVE LACK OF LOW LEVEL MOISTURE...THE BROAD ASCENT AHEAD OF THIS IMPULSE COMBINED WITH FAIRLY STEEP MID LEVEL LAPSE RATES SHOULD BE SUFFICIENT TO GENERATE SOME THUNDERSTORMS...ESPECIALLY ACROSS OUR NORTHERN AND EASTERN COUNTIES...FROM LATE IN THE AFTERNOON INTO EARLY MONDAY NIGHT. HAVE INTRODUCED DETAILS IN TIMING OF POP FORECAST TO ACCOUNT FOR THIS SCENARIO. EVEN AS THIS INITIAL SYSTEM PUSHES OFF TO THE SOUTH ON TUESDAY ANOTHER SHORTWAVE WILL BE APPROACHING FROM THE NORTHWEST...HOWEVER BY TUESDAY NIGHT AND WEDNESDAY A SURFACE RIDGE WILL HAVE BUILT ACROSS THE AREA INCREASING DRY AIR AND SUBSIDENCE IN THE LOWER SECTIONS OF THE ATMOSPHERIC COLUMN. THIS WILL MITIGATE PRECIPITATION CHANCES AND INTENSITY...BUT EVEN SO CHANCE POPS ARE WARRANTED THOUGH NO REAL IMPACTS ARE ANTICIPATED. FINALLY...THE STRONGEST 500 MB TROUGH OF THE WEEK WILL TRAVERSE THE REGION AROUND THURSDAY AND THURSDAY NIGHT IN CONJUNCTION WITH THE AFOREMENTIONED SURFACE HIGH SLIDING OFF TO THE EAST AND A MODEST RETURN OF LOW LEVEL MOISTURE. THIS APPEARS TO BE THE BEST OPPORTUNITY FOR WIDESPREAD PRECIPITATION THIS WEEK...HOWEVER...MODEL CONSISTENCY HAS NOT BEEN THE GREATEST WITH THIS SYSTEM AND THERE ARE STILL TIMING ISSUES SO POPS HAVE BEEN HELD GENERALLY IN THE 40S FOR NOW. IT IS EXPECTED THAT IF THIS SCENARIO HOLDS UP AND WE CAN REFINE THE ARRIVAL OF THE RAIN THEN POPS FOR PART OF THIS TIME FRAME WILL LIKELY INCREASE IN THE COMING DAYS. IN ANY EVENT...THE SEVERE WEATHER THREAT LATER THIS WEEK DOES NOT APPEAR PARTICULARLY NOTEWORTHY. LOOKING INTO THE EXTENDED FORECAST...THERE CONTINUE TO BE INDICATIONS THAT IN WAKE OF THE THURSDAY/THURSDAY NIGHT TROUGH PASSAGE A PERIOD OF DEEP LAYERED RIDGING SHOULD FOLLOW...PROVIDING A COUPLE OF DAYS OF SUNNY AND RELATIVELY COOL WEATHER RIGHT AROUND THE FOURTH OF JULY. OBVIOUSLY ANYONE WITH OUTDOOR HOLIDAY PLANS SHOULD CONTINUE TO MONITOR THE FORECAST THROUGHOUT THE WEEK BUT EARLY SIGNS POINT TO GOOD WEATHER AROUND SATURDAY. && .AVIATION...29/00Z ISSUED AT 700 PM CDT SUN JUN 28 2015 MAIN CONCERNS WILL INITIALY BE RESTRICTIONS WITH SCT EVENING CONVECTION...AND POTENTIALLY MVFR RADIATION FOG INTO EARLY MON MORNING. VFR CONDITIONS ARE PREVALENT STATEWIDE AT 00Z AND WHILE INDIVIDUAL SHOWERS AND STORMS MAY PRODUCE ISOLATED AND BRIEF IFR/MVFR RESTRICTIONS CONFIDENCE IS NOT GREAT ENOUGH TO DEVIATE FROM VFR AT ANY PARTICULAR LOCATION. PATCHY MVFR FOG MAY DEVELOP INTO THE NIGHT AS WELL...ESPECIALLY SE NEAR KOTM WHERE HIGHER LOW LEVEL MOISTURE WILL LINGER LONGER. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...REV LONG TERM...LEE AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1237 PM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1236 PM CDT SAT JUN 27 2015 VISIBLE SATELLITE IMAGES AND SURFACE WIND FIELDS SHOW A WEAK CONVERGENCE AXIS ROUGHLY ALONG THE MS RIVER FROM SE OF DBQ THROUGH THE QUAD CITIES TO MACOMB IL. RECENT RADAR IMAGES SHOW A FEW VERY WEAK RETURNS NEAR THE MACOMB AREA. THIS AXIS IS WHERE THE GREAT LAKES AIRMASS WITH ITS SLIGHTLY LOWER DEWPOINTS CONVERGED WITH THE WEAK MORE NORTHERLY FLOW OUT OF THE SURFACE RIDGE AXIS LOCATED FROM EASTERN NEB TO NORTHERN WI. IT WILL BE THIS ALONG AXIS WHERE ISOLATED SHOWERS MAY FIRST DEVELOP EARLY THIS AFTERNOON. THE COVERAGE AND INTENSITY OF SHOWERS WILL BE LIMITED BY A CONVERGENT...SUBSIDENT FLOW ALOFT AS A SHORTWAVE RIDGE OVER THE UPPER MS VALLEY MIGRATES OVER THE REGION THIS AFTERNOON. WILL THUS KEEP ONLY SLIGHT CHANCE POPS FOR SHOWERS AND BRIEF THUNDERSTORMS GOING FOR THIS AFTERNOON WITH TEMPERATURES ON TRACK TO TOP OUT IN THE UPPER 70S TO NEAR 80. && .SYNOPSIS... ISSUED AT 400 AM CDT SAT JUN 27 2015 UPPER LEVEL LOW WAS SITUATED IN LOWER MI WITH THE BULK OF THE RAIN WELL TO OUR EAST. HOWEVER...THERE IS JUST ENOUGH SURFACE CONVERGENCE TO DEVELOP A FEW 50DBZ SHOWERS IN NORTHERN IL AS CLOSE AS ROCHELLE AND OREGON IN OGLE COUNTY. THESE SHOWERS WERE MOVING SOUTHWEST AND SHOULD TURN MORE SOUTHERLY AROUND THE UPPER LOW. THE FARTHER WEST THEY GET THE CONVERGENCE WEAKENS SO NOT EXPECTING THE SHOWERS TO MAKE IT INTO THE DVN CWA. HOWEVER...WILL MONITOR RADAR TRENDS. MEANWHILE BACK AT THE RANCH...SKIES IN THE CWA WERE CLEAR TO PARTLY CLOUDY WITH 3 AM TEMPERATURES IN THE UPPER 50S TO LOWER 60S SO A RATHER COMFORTABLE EARLY MORNING IN PROGRESS. ELSEWHERE...WATER VAPOR LOOPS SHOW A WEAK VORT MAX DIVING INTO NORTHERN IA AND ANOTHER STRONGER WAVE IN MANITOBA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT SAT JUN 27 2015 FORECAST FOCUS ON ISOLATED SHOWERS OR STORMS THIS AFTERNOON THEN THUNDERSTORMS LIKELY IN OUR NW CWA LATE TONIGHT. TODAY...APPARENTLY MOTHER NATURE WILL NOT ALLOW FOR A DRY DAY AS OPERATIONAL MODELS SUGGEST ISOLATED SHOWERS AND THUNDERSTORMS DEVELOPING THIS AFTERNOON...MAINLY NEAR AND WEST OF THE MS RIVER. THE HRRR DEVELOPS THIS BY EARLY AFTERNOON BUT DIMINISHES THE ACTIVITY TOWARDS EVENING. I CERTAINLY CAN/T IGNORE THE FACT THAT THERE WILL BE WEAK CONVERGENCE AT THE SURFACE/LOW LEVELS...THE CONVECTIVE TEMPERATURE IN THE MID 70S WILL BE REACHED BY EARLY AFTERNOON AND LAPSE RATES STEEPEN ALONG WITH ENOUGH MOISTURE. THERE WILL ALSO BE A WEAK VORT MAX TO AID LIFT. THEREFORE...HAVE ADDED THE MENTION OF NEAR 20 PERCENT POPS FOR THIS AFTERNOON IN ROUGHLY OUR WESTERN HALF. ANY STORM THAT DEVELOPS COULD CAUSE BRIEF HEAVY DOWNPOURS BUT EXPECTING ISOLATED COVERAGE WHICH MEANS MOST AREAS SHOULD REMAIN DRY ALONG WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES. THIS WILL BE ANOTHER DAY OF BELOW NORMAL TEMPERATURES...WITH HIGHS IN THE UPPER 70S. THIS IS BASED ON USING THE SURFACE PARCEL TRAJECTORY METHOD WITH OUR AIRMASS COMING FROM NORTHERN WI WHERE THEIR OBSERVED HIGHS YESTERDAY WERE IN THE UPPER 70S. TONIGHT...SHOULD BE A DRY EVENING BUT THEN ECMWF/GFS/NAM/CANADIAN ALL SIMILAR IN ROLLING SHOWERS AND THUNDERSTORMS INTO OUR NW CWA BY LATE TONIGHT. THIS WILL BE AHEAD OF A SIGNIFICANT SHORT WAVE TROUGH IN THE NORTHWEST FLOW PROVIDING DECENT FORCING. DEEP LAYER SHEAR WILL BE GRADUALLY INCREASING ALONG WITH PRECIPITABLE WATER INCREASING TO OVER 1 INCH WHILE SHOWALTERS DROP INTO THE NEGATIVE NUMBERS. THEREFORE...I HAVE RAISED POPS TO LIKELY IN THE FAR NW BY SUNRISE. MINIMUM TEMPERATURES WILL BE COMFORTABLE AGAIN BEFORE THE CLOUDS ARRIVE. LOWS WILL RANGE FROM THE MID 50S FAR EAST TO THE LOWER 60S FAR WEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CDT SAT JUN 27 2015 LITTLE CHANGE NOTED IN OVERALL PATTERN WITH ACTIVE NORTHWEST FLOW TO PERSIST THROUGH THE PERIOD AND TEMPS NEAR TO BELOW NORMAL. SUNDAY AND SUNDAY NIGHT...GOOD FORCING WITH SHORTWAVE AND FAVORABLE LEFT EXIT REGION LIFT QUADRANT OF 80 PLUS KT 300 MB JET DIVING FROM NORTHERN PLAINS THROUGH MID MISSISSIPPI VALLEY... AND WEAK SURFACE CYCLONE WITH TRIPLE POINT ALL SUPPORTIVE OF WIDESPREAD SHOWERS AND A FEW STORMS SUNDAY INTO SUNDAY EVE. THE PRECIPITATION SHOULD CONTINUE SLIDING S/E SUNDAY AM WITH REDEVELOPMENT DURING THE AFTN. HEAVIEST RAINS 0.5 TO 1 PLUS INCHES SUGGESTED TO FALL ACROSS PORTIONS OF THE WESTERN AND SOUTHERN CWA VICINITY OF TRIPLE POINT AHEAD OF SURFACE LOW AS LAYER PRECIPITABLE WATER VALUES SURGE TO NEARLY 1.5 INCHES. THIS WILL NEED TO BE WATCHED FOR FLASH FLOODING ISSUES ESPECIALLY FOR SOUTHERN CWA WHICH HAS BEEN HIT HARD WITH SIGNIFICANT RAINS OF LATE AND GROUND IS SATURATED. CONDITIONAL RISK FOR STRONG TO ISOLATED SEVERE STORMS EXISTS AND THIS IS DEPENDENT ON AMOUNT OF SOLAR INSOLATION AND SUBSEQUENT DESTABILIZATION. AT THIS TIME...EXCEPT FOR A WHILE SUNDAY AM MAINLY SOUTH/EAST CWA... I DO NOT FORESEE A LOT OF SOLAR INSOLATION AND AS SUCH HAVE LOWERED MAX TEMPS A BIT (WIDESPREAD 70S) LEADING TO LOW THREAT FOR A STRONG TO ISOLATED SEVERE STORM. HOWEVER... IF MORE SUNSHINE AND SUBSEQUENT INSTABILITY OCCURS THAN CURRENTLY ANTICIPATING THEN THREAT FOR A FEW SEVERE STORMS WILL INCREASE GIVEN PRESENCE OF STRENGTHENING 0-6 KM BULK SHEAR 30-40 KTS DURING THE AFTN. PRECIPITATION SHOULD TAPER OFF FROM NORTHWEST TO SOUTHEAST SUNDAY EVENING WITH SOME CHANCE OF SHOWERS LINGERING OVERNIGHT IN WRAP-AROUND OVER NORTH AND EAST PORTIONS OF THE CWA. MONDAY THROUGH FRIDAY... A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL BRING PERIODIC RAIN CHANCES NEXT WEEK. TRYING TO TIME THESE WAVES REMAINS VERY DIFFICULT THIS FAR OUT AND UNFORTUNATELY DICTATES THE DAILY BARRAGE OF RAIN CHANCES IN THE FORECAST EVEN THOUGH WE SHOULD SEE MANY DRY HOURS. TEMPS NEAR TO BELOW NORMAL WITH HIGHS MAINLY IN THE 70S TO NEAR 80 AND LOWS IN THE 50S/60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1236 PM CDT SAT JUN 27 2015 ISOLATED SHOWERS AND THUNDERSTORMS THIS AFTERNOON ARE EXPECTED TO BE TOO FEW AND FAR APART TO AFFECT THE TERMINALS AND HAVE BEEN LEFT OUT OF THE FORECASTS FOR NOW. HIGH PRESSURE...BOTH AT THE SURFACE AND ALOFT WILL KEEP CONDITIONS VFR WITH LIGHT NORTH WINDS. TONIGHT...AN INCOMING UPPER LEVEL DISTURBANCE MAY SPREAD THUNDERSTORMS INTO EASTERN IA...MAINLY NW OF THE CID AND DBQ TERMINALS TOWARD SUNRISE. A BETTER CHANCE FOR MORE WIDESPREAD SHOWERS AND THUNDERSTORMS WILL ARRIVE LATER SUNDAY MORNING...AND PROB30 GROUPS HAVE BEEN INTRODUCED FOR THUNDERSTORMS WITH MVFR CONDITIONS AT ALL SITES. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...SHEETS SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
657 AM CDT SAT JUN 27 2015 .SYNOPSIS... ISSUED AT 400 AM CDT SAT JUN 27 2015 UPPER LEVEL LOW WAS SITUATED IN LOWER MI WITH THE BULK OF THE RAIN WELL TO OUR EAST. HOWEVER...THERE IS JUST ENOUGH SURFACE CONVERGENCE TO DEVELOP A FEW 50DBZ SHOWERS IN NORTHERN IL AS CLOSE AS ROCHELLE AND OREGON IN OGLE COUNTY. THESE SHOWERS WERE MOVING SOUTHWEST AND SHOULD TURN MORE SOUTHERLY AROUND THE UPPER LOW. THE FARTHER WEST THEY GET THE CONVERGENCE WEAKENS SO NOT EXPECTING THE SHOWERS TO MAKE IT INTO THE DVN CWA. HOWEVER...WILL MONITOR RADAR TRENDS. MEANWHILE BACK AT THE RANCH...SKIES IN THE CWA WERE CLEAR TO PARTLY CLOUDY WITH 3 AM TEMPERATURES IN THE UPPER 50S TO LOWER 60S SO A RATHER COMFORTABLE EARLY MORNING IN PROGRESS. ELSEWHERE...WATER VAPOR LOOPS SHOW A WEAK VORT MAX DIVING INTO NORTHERN IA AND ANOTHER STRONGER WAVE IN MANITOBA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT SAT JUN 27 2015 FORECAST FOCUS ON ISOLATED SHOWERS OR STORMS THIS AFTERNOON THEN THUNDERSTORMS LIKELY IN OUR NW CWA LATE TONIGHT. TODAY...APPARENTLY MOTHER NATURE WILL NOT ALLOW FOR A DRY DAY AS OPERATIONAL MODELS SUGGEST ISOLATED SHOWERS AND THUNDERSTORMS DEVELOPING THIS AFTERNOON...MAINLY NEAR AND WEST OF THE MS RIVER. THE HRRR DEVELOPS THIS BY EARLY AFTERNOON BUT DIMINISHES THE ACTIVITY TOWARDS EVENING. I CERTAINLY CAN`T IGNORE THE FACT THAT THERE WILL BE WEAK CONVERGENCE AT THE SURFACE/LOW LEVELS...THE CONVECTIVE TEMPERATURE IN THE MID 70S WILL BE REACHED BY EARLY AFTERNOON AND LAPSE RATES STEEPEN ALONG WITH ENOUGH MOISTURE. THERE WILL ALSO BE A WEAK VORT MAX TO AID LIFT. THEREFORE...HAVE ADDED THE MENTION OF NEAR 20 PERCENT POPS FOR THIS AFTERNOON IN ROUGHLY OUR WESTERN HALF. ANY STORM THAT DEVELOPS COULD CAUSE BRIEF HEAVY DOWNPOURS BUT EXPECTING ISOLATED COVERAGE WHICH MEANS MOST AREAS SHOULD REMAIN DRY ALONG WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES. THIS WILL BE ANOTHER DAY OF BELOW NORMAL TEMPERATURES...WITH HIGHS IN THE UPPER 70S. THIS IS BASED ON USING THE SURFACE PARCEL TRAJECTORY METHOD WITH OUR AIRMASS COMING FROM NORTHERN WI WHERE THEIR OBSERVED HIGHS YESTERDAY WERE IN THE UPPER 70S. TONIGHT...SHOULD BE A DRY EVENING BUT THEN ECMWF/GFS/NAM/CANADIAN ALL SIMILAR IN ROLLING SHOWERS AND THUNDERSTORMS INTO OUR NW CWA BY LATE TONIGHT. THIS WILL BE AHEAD OF A SIGNIFICANT SHORT WAVE TROUGH IN THE NORTHWEST FLOW PROVIDING DECENT FORCING. DEEP LAYER SHEAR WILL BE GRADUALLY INCREASING ALONG WITH PRECIPITABLE WATER INCREASING TO OVER 1 INCH WHILE SHOWALTERS DROP INTO THE NEGATIVE NUMBERS. THEREFORE...I HAVE RAISED POPS TO LIKELY IN THE FAR NW BY SUNRISE. MINIMUM TEMPERATURES WILL BE COMFORTABLE AGAIN BEFORE THE CLOUDS ARRIVE. LOWS WILL RANGE FROM THE MID 50S FAR EAST TO THE LOWER 60S FAR WEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CDT SAT JUN 27 2015 LITTLE CHANGE NOTED IN OVERALL PATTERN WITH ACTIVE NORTHWEST FLOW TO PERSIST THROUGH THE PERIOD AND TEMPS NEAR TO BELOW NORMAL. SUNDAY AND SUNDAY NIGHT...GOOD FORCING WITH SHORTWAVE AND FAVORABLE LEFT EXIT REGION LIFT QUADRANT OF 80+ KT 300 MB JET DIVING FROM NORTHERN PLAINS THROUGH MID MISSISSIPPI VALLEY... AND WEAK SURFACE CYCLONE WITH TRIPLE POINT ALL SUPPORTIVE OF WIDESPREAD SHOWERS AND A FEW STORMS SUNDAY INTO SUNDAY EVE. THE PRECIPITATION SHOULD CONTINUE SLIDING S/E SUNDAY AM WITH REDEVELOPMENT DURING THE AFTN. HEAVIEST RAINS 0.5 TO 1+ INCHES SUGGESTED TO FALL ACROSS PORTIONS OF THE WESTERN AND SOUTHERN CWA VICINITY OF TRIPLE POINT AHEAD OF SURFACE LOW AS LAYER PRECIPITABLE WATER VALUES SURGE TO NEARLY 1.5 INCHES. THIS WILL NEED TO BE WATCHED FOR FLASH FLOODING ISSUES ESPECIALLY FOR SOUTHERN CWA WHICH HAS BEEN HIT HARD WITH SIGNIFICANT RAINS OF LATE AND GROUND IS SATURATED. CONDITIONAL RISK FOR STRONG TO ISOLATED SEVERE STORMS EXISTS AND THIS IS DEPENDENT ON AMOUNT OF SOLAR INSOLATION AND SUBSEQUENT DESTABILIZATION. AT THIS TIME... EXCEPT FOR A WHILE SUNDAY AM MAINLY SOUTH/EAST CWA... I DO NOT FORESEE A LOT OF SOLAR INSOLATION AND AS SUCH HAVE LOWERED MAX TEMPS A BIT (WIDESPREAD 70S) LEADING TO LOW THREAT FOR A STRONG TO ISOLATED SEVERE STORM. HOWEVER... IF MORE SUNSHINE AND SUBSEQUENT INSTABILITY OCCURS THAN CURRENTLY ANTICIPATING THEN THREAT FOR A FEW SEVERE STORMS WILL INCREASE GIVEN PRESENCE OF STRENGTHENING 0-6 KM BULK SHEAR 30-40 KTS DURING THE AFTN. PRECIPITATION SHOULD TAPER OFF FROM NORTHWEST TO SOUTHEAST SUNDAY EVENING WITH SOME CHANCE OF SHOWERS LINGERING OVERNIGHT IN WRAP-AROUND OVER NORTH AND EAST PORTIONS OF THE CWA. MONDAY THROUGH FRIDAY... A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL BRING PERIODIC RAIN CHANCES NEXT WEEK. TRYING TO TIME THESE WAVES REMAINS VERY DIFFICULT THIS FAR OUT AND UNFORTUNATELY DICTATES THE DAILY BARRAGE OF RAIN CHANCES IN THE FORECAST EVEN THOUGH WE SHOULD SEE MANY DRY HOURS. TEMPS NEAR TO BELOW NORMAL WITH HIGHS MAINLY IN THE 70S TO NEAR 80 AND LOWS IN THE 50S/60S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 655 AM CDT SAT JUN 27 2015 MVFR VIS BR TIL 16Z/27 THEN VFR CONDS THROUGH MUCH OF THIS TAF CYCLE. ISOLATED SHOWERS OR THUNDERSTORMS WILL DEVELOP THIS AFTERNOON. DID MENTION VCSH AT KCID BUT CONFIDENCE IS LOW IF THESE SHOWERS WILL IMPACT THE REMAINDER OF THE TAF SITES. LATER TONIGHT AN AREA OF SHOWERS AND THUNDERSTORMS WILL MOVE INTO PORTIONS OF EASTERN IOWA BUT THE ONLY TAF SITE IMPACTED BY THESE STORMS TOWARDS SUNDAY MORNING SHOULD BE KCID. RAIN AND A FEW THUNDERSTORMS WILL THEN BE WIDESPREAD ON SUNDAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
403 AM CDT SAT JUN 27 2015 .SYNOPSIS... ISSUED AT 400 AM CDT SAT JUN 27 2015 UPPER LEVEL LOW WAS SITUATED IN LOWER MI WITH THE BULK OF THE RAIN WELL TO OUR EAST. HOWEVER...THERE IS JUST ENOUGH SURFACE CONVERGENCE TO DEVELOP A FEW 50DBZ SHOWERS IN NORTHERN IL AS CLOSE AS ROCHELLE AND OREGON IN OGLE COUNTY. THESE SHOWERS WERE MOVING SOUTHWEST AND SHOULD TURN MORE SOUTHERLY AROUND THE UPPER LOW. THE FARTHER WEST THEY GET THE CONVERGENCE WEAKENS SO NOT EXPECTING THE SHOWERS TO MAKE IT INTO THE DVN CWA. HOWEVER...WILL MONITOR RADAR TRENDS. MEANWHILE BACK AT THE RANCH...SKIES IN THE CWA WERE CLEAR TO PARTLY CLOUDY WITH 3 AM TEMPERATURES IN THE UPPER 50S TO LOWER 60S SO A RATHER COMFORTABLE EARLY MORNING IN PROGRESS. ELSEWHERE...WATER VAPOR LOOPS SHOW A WEAK VORT MAX DIVING INTO NORTHERN IA AND ANOTHER STRONGER WAVE IN MANITOBA. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 400 AM CDT SAT JUN 27 2015 FORECAST FOCUS ON ISOLATED SHOWERS OR STORMS THIS AFTERNOON THEN THUNDERSTORMS LIKELY IN OUR NW CWA LATE TONIGHT. TODAY...APPARENTLY MOTHER NATURE WILL NOT ALLOW FOR A DRY DAY AS OPERATIONAL MODELS SUGGEST ISOLATED SHOWERS AND THUNDERSTORMS DEVELOPING THIS AFTERNOON...MAINLY NEAR AND WEST OF THE MS RIVER. THE HRRR DEVELOPS THIS BY EARLY AFTERNOON BUT DIMINISHES THE ACTIVITY TOWARDS EVENING. I CERTAINLY CAN`T IGNORE THE FACT THAT THERE WILL BE WEAK CONVERGENCE AT THE SURFACE/LOW LEVELS...THE CONVECTIVE TEMPERATURE IN THE MID 70S WILL BE REACHED BY EARLY AFTERNOON AND LAPSE RATES STEEPEN ALONG WITH ENOUGH MOISTURE. THERE WILL ALSO BE A WEAK VORT MAX TO AID LIFT. THEREFORE...HAVE ADDED THE MENTION OF NEAR 20 PERCENT POPS FOR THIS AFTERNOON IN ROUGHLY OUR WESTERN HALF. ANY STORM THAT DEVELOPS COULD CAUSE BRIEF HEAVY DOWNPOURS BUT EXPECTING ISOLATED COVERAGE WHICH MEANS MOST AREAS SHOULD REMAIN DRY ALONG WITH MOSTLY SUNNY TO PARTLY CLOUDY SKIES. THIS WILL BE ANOTHER DAY OF BELOW NORMAL TEMPERATURES...WITH HIGHS IN THE UPPER 70S. THIS IS BASED ON USING THE SURFACE PARCEL TRAJECTORY METHOD WITH OUR AIRMASS COMING FROM NORTHERN WI WHERE THEIR OBSERVED HIGHS YESTERDAY WERE IN THE UPPER 70S. TONIGHT...SHOULD BE A DRY EVENING BUT THEN ECMWF/GFS/NAM/CANADIAN ALL SIMILAR IN ROLLING SHOWERS AND THUNDERSTORMS INTO OUR NW CWA BY LATE TONIGHT. THIS WILL BE AHEAD OF A SIGNIFICANT SHORT WAVE TROUGH IN THE NORTHWEST FLOW PROVIDING DECENT FORCING. DEEP LAYER SHEAR WILL BE GRADUALLY INCREASING ALONG WITH PRECIPITABLE WATER INCREASING TO OVER 1 INCH WHILE SHOWALTERS DROP INTO THE NEGATIVE NUMBERS. THEREFORE...I HAVE RAISED POPS TO LIKELY IN THE FAR NW BY SUNRISE. MINIMUM TEMPERATURES WILL BE COMFORTABLE AGAIN BEFORE THE CLOUDS ARRIVE. LOWS WILL RANGE FROM THE MID 50S FAR EAST TO THE LOWER 60S FAR WEST. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 400 AM CDT SAT JUN 27 2015 LITTLE CHANGE NOTED IN OVERALL PATTERN WITH ACTIVE NORTHWEST FLOW TO PERSIST THROUGH THE PERIOD AND TEMPS NEAR TO BELOW NORMAL. SUNDAY AND SUNDAY NIGHT...GOOD FORCING WITH SHORTWAVE AND FAVORABLE LEFT EXIT REGION LIFT QUADRANT OF 80+ KT 300 MB JET DIVING FROM NORTHERN PLAINS THROUGH MID MISSISSIPPI VALLEY... AND WEAK SURFACE CYCLONE WITH TRIPLE POINT ALL SUPPORTIVE OF WIDESPREAD SHOWERS AND A FEW STORMS SUNDAY INTO SUNDAY EVE. THE PRECIPITATION SHOULD CONTINUE SLIDING S/E SUNDAY AM WITH REDEVELOPMENT DURING THE AFTN. HEAVIEST RAINS 0.5 TO 1+ INCHES SUGGESTED TO FALL ACROSS PORTIONS OF THE WESTERN AND SOUTHERN CWA VICINITY OF TRIPLE POINT AHEAD OF SURFACE LOW AS LAYER PRECIPITABLE WATER VALUES SURGE TO NEARLY 1.5 INCHES. THIS WILL NEED TO BE WATCHED FOR FLASH FLOODING ISSUES ESPECIALLY FOR SOUTHERN CWA WHICH HAS BEEN HIT HARD WITH SIGNIFICANT RAINS OF LATE AND GROUND IS SATURATED. CONDITIONAL RISK FOR STRONG TO ISOLATED SEVERE STORMS EXISTS AND THIS IS DEPENDENT ON AMOUNT OF SOLAR INSOLATION AND SUBSEQUENT DESTABILIZATION. AT THIS TIME... EXCEPT FOR A WHILE SUNDAY AM MAINLY SOUTH/EAST CWA... I DO NOT FORESEE A LOT OF SOLAR INSOLATION AND AS SUCH HAVE LOWERED MAX TEMPS A BIT (WIDESPREAD 70S) LEADING TO LOW THREAT FOR A STRONG TO ISOLATED SEVERE STORM. HOWEVER... IF MORE SUNSHINE AND SUBSEQUENT INSTABILITY OCCURS THAN CURRENTLY ANTICIPATING THEN THREAT FOR A FEW SEVERE STORMS WILL INCREASE GIVEN PRESENCE OF STRENGTHENING 0-6 KM BULK SHEAR 30-40 KTS DURING THE AFTN. PRECIPITATION SHOULD TAPER OFF FROM NORTHWEST TO SOUTHEAST SUNDAY EVENING WITH SOME CHANCE OF SHOWERS LINGERING OVERNIGHT IN WRAP-AROUND OVER NORTH AND EAST PORTIONS OF THE CWA. MONDAY THROUGH FRIDAY... A SERIES OF DISTURBANCES IN NORTHWEST FLOW WILL BRING PERIODIC RAIN CHANCES NEXT WEEK. TRYING TO TIME THESE WAVES REMAINS VERY DIFFICULT THIS FAR OUT AND UNFORTUNATELY DICTATES THE DAILY BARRAGE OF RAIN CHANCES IN THE FORECAST EVEN THOUGH WE SHOULD SEE MANY DRY HOURS. TEMPS NEAR TO BELOW NORMAL WITH HIGHS MAINLY IN THE 70S TO NEAR 80 AND LOWS IN THE 50S/60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1202 AM CDT SAT JUN 27 2015 RECENT TRENDS AND MODEL GUIDANCE SUPPORT SOME MVFR...AND POSSIBLY IFR FOG DEVELOPING OVERNIGHT. KCID HAS ALREADY CLEARED OUT...AND KBRL HAD SOME RECENT RAINFALL...SO I HAVE INCLUDED A TEMPO FOR 2SM BR. KEPT VSBYS AT MVFR FOR KDBQ/KMLI. THERE IS A LOW PROBABILITY OF ISOLATED STORMS DEVELOPING SATURDAY AFTERNOON AND EVENING IN EASTERN IOWA...BUT WITH LOW CONFIDENCE...HAVE OPTED TO LEAVE OUT OF TAF FOR NOW AND PASS ALONG FOR LATER SHIFTS TO MONITOR. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
946 PM EDT Sun Jun 28 2015 ...Forecast Update... Issued at 940 PM EDT Sun Jun 28 2015 POPs still look good for overnight with isld to scattered showers and perhaps a rumble of thunder moving through our region overnight as the complex of storms over IL/MO currently, weakens and tracks east through the Ohio Valley. Since clouds are coming in a bit earlier than previously forecast, increased low temps for tonight in some areas. Low temps should hold in the low to mid 60s. Issued at 535 PM EDT Sun Jun 28 2015 Updated the POPs to bring a 20% chance of a shower/storm into Dubois County, IN by 23-0Z. The current complex of convection on the IL/IN border is holding together pretty decently attm. Still think it will weaken as it reaches dry air over southern IN, but at least some showery activity should still survive. .SHORT TERM (Now through Monday Night)... Issued at 250 PM EDT Sun Jun 28 2015 Shortwave ridge in the NW flow aloft, and a bubble of surface high pressure, have brought the Ohio Valley unusually mild temps and low humidity for late June. Next upper vort, and a decent surface reflection, diving into SE Iowa and NE Missouri, almost looking more like a Clipper. Main challenge is timing and impact of what will most likely be two separate rounds of precip. Warm advection wing over west-central Illinois appears to be struggling as it moves into a less favorable environment, but there is a decent cu field extending to its south. Have mostly followed the hi-res model data, which would suggest that timing will be a little faster than previously advertised. Still seems like precip chances will be maximized between 06-12Z Monday over north-central KY and especially southern IN. This is a fairly dynamic system, but precipitable water values around 1.3 to 1.4 inches are a bit lackluster for this time of year, and there is quite a bit of low-level dry air. Therefore will cap POPs around 50% and keep QPF fairly low, especially with the first batch of warm advection precip. By late morning the warm advection precip will exit the Bluegrass region, and we`ll be in a modest warm sector with gusty SW winds. Temps will remain fairly cool aloft, and leftover boundaries will focus afternoon convection. SPC has a slight risk as impressive lapse rates will support hailers. However, the more favorable wind fields will be to our north and east, limiting the SVR wind threat. Better afternoon/evening precip chances will be in the south and east, dropping off around midnight. Cooler than normal temps tonight and Monday will recover to near climo Monday night with clouds and increasing moisture. .LONG TERM (Tuesday through Sunday)... Issued at 255 PM EDT Sun Jun 28 2015 The synoptic pattern at the start of the long term period will feature rather impressive ridging across the western CONUS, which will result in a seasonably amplified trough across the Ohio Valley. This regime will slowly deamplify through the week, but mean troughing will prevail over the Ohio Valley through the extended period making for rather unsettled conditions and near normal to slightly below normal temperatures. The long term period will be characterized by northwest flow aloft, through which multiple PV anomalies will ride through. These disturbances are inherently difficult to time, so while confidence in precipitation through the extended is high, confidence in exact timing remains low. Tuesday will likely start out mainly dry as the Ohio Valley lies in between systems. However, another compact PV anomaly diving through the mean trough aloft will slide through the region Tuesday afternoon into Tuesday evening. A surface trough and any lingering differential heating/outflow boundaries will trigger convection during this timeframe. Moderate instability on the order of 1000-2000+ K/kg of MLCAPE coupled with about 30-40 knots of deep-layer shear (0-6km) may be enough to support some strong to marginally severe storms Tuesday afternoon. The main threats with these would be hail up to the size of quarters given seasonably low wet bulb zero heights (10-11k feet) and localized strong wind gusts. The main question on Tuesday will be the exact timing of the upper-level disturbance and the degree of which we are able to destabilize ahead of it. The remainder of the long term will be characterized by the upper-level flow flattening out just a bit, allowing a frontal boundary to stall somewhere near or over the region Wednesday into the upcoming weekend. Subtle disturbances riding along this boundary will lead to rounds of showers and thunderstorms, some of which could be overnight. The location of the boundary will be key as a more southern location (like the 28/12Z GEM) solution would dry out the northern CWA, while a more northern location 28/12Z GFS/ECMWF/GEFS would keep much of the CWA in play for these rounds of storms. Given the general agreement of the latter models, will side on the wetter side of things keeping 40-60 pops in Wednesday through Saturday. It certainly won`t rain this whole time, but the pattern will favor progressive storm systems through the region. Given how wet we have become over the past week or two, flooding may become a concern once again especially if the boundary ends up stalling over the Ohio Valley for an extended period of time. && .AVIATION (00Z TAF Update)... Issued at 740 PM EDT Sun Jun 28 2015 A quick moving low pressure system will push through the Ohio Valley late tonight into tomorrow. This system will bring showers to all TAF sites late tonight...probably more numerous at SDF/LEX late tonight into tomorrow morning. Instability overnight into the morning hours won`t be great so will not include a thunder mention in the TAFs at this point. Winds will shift from WSW to S overnight. The forecast for tomorrow isn`t real clear due to the timing of the low pressure system through Ohio Valley. Current obs/trends indicate it`s moving faster than some of the 12Z models indicate. Thus, will side with the faster HRRR and 18Z NAM. This should largely end showery activity at SDF during the morning hours with perhaps a period of MVFR cigs during the later morning hours. LEX may experience these MVFR cigs as well but the signal in the models isn`t as strong there. The cold front associated with this low pressure system should layout somewhere over central KY or northern TN for tomorrow afternoon. It`s unclear exactly where that location will be at this time, so will include VCSH at BWG/LEX which will be closest to the boundary. Will need to watch the front`s progression in coming TAF issuances to better define timing and if a thunder mention should be included in some of the TAFs for tomorrow afternoon/evening. Winds will be gusty tomorrow afternoon between 20-25 kts. The fropa should shift winds from SSW to WSW early tomorrow afternoon. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........AMS Short Term.....RAS Long Term......KJD Aviation.......AMS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
744 PM EDT Sun Jun 28 2015 ...Updated Aviation Discussion... ...Forecast Update... Issued at 535 PM EDT Sun Jun 28 2015 Updated the POPs to bring a 20% chance of a shower/storm into Dubois County, IN by 23-0Z. The current complex of convection on the IL/IN border is holding together pretty decently attm. Still think it will weaken as it reaches dry air over southern IN, but at least some showery activity should still survive. .SHORT TERM (Now through Monday Night)... Issued at 250 PM EDT Sun Jun 28 2015 Shortwave ridge in the NW flow aloft, and a bubble of surface high pressure, have brought the Ohio Valley unusually mild temps and low humidity for late June. Next upper vort, and a decent surface reflection, diving into SE Iowa and NE Missouri, almost looking more like a Clipper. Main challenge is timing and impact of what will most likely be two separate rounds of precip. Warm advection wing over west-central Illinois appears to be struggling as it moves into a less favorable environment, but there is a decent cu field extending to its south. Have mostly followed the hi-res model data, which would suggest that timing will be a little faster than previously advertised. Still seems like precip chances will be maximized between 06-12Z Monday over north-central KY and especially southern IN. This is a fairly dynamic system, but precipitable water values around 1.3 to 1.4 inches are a bit lackluster for this time of year, and there is quite a bit of low-level dry air. Therefore will cap POPs around 50% and keep QPF fairly low, especially with the first batch of warm advection precip. By late morning the warm advection precip will exit the Bluegrass region, and we`ll be in a modest warm sector with gusty SW winds. Temps will remain fairly cool aloft, and leftover boundaries will focus afternoon convection. SPC has a slight risk as impressive lapse rates will support hailers. However, the more favorable wind fields will be to our north and east, limiting the SVR wind threat. Better afternoon/evening precip chances will be in the south and east, dropping off around midnight. Cooler than normal temps tonight and Monday will recover to near climo Monday night with clouds and increasing moisture. .LONG TERM (Tuesday through Sunday)... Issued at 255 PM EDT Sun Jun 28 2015 The synoptic pattern at the start of the long term period will feature rather impressive ridging across the western CONUS, which will result in a seasonably amplified trough across the Ohio Valley. This regime will slowly deamplify through the week, but mean troughing will prevail over the Ohio Valley through the extended period making for rather unsettled conditions and near normal to slightly below normal temperatures. The long term period will be characterized by northwest flow aloft, through which multiple PV anomalies will ride through. These disturbances are inherently difficult to time, so while confidence in precipitation through the extended is high, confidence in exact timing remains low. Tuesday will likely start out mainly dry as the Ohio Valley lies in between systems. However, another compact PV anomaly diving through the mean trough aloft will slide through the region Tuesday afternoon into Tuesday evening. A surface trough and any lingering differential heating/outflow boundaries will trigger convection during this timeframe. Moderate instability on the order of 1000-2000+ K/kg of MLCAPE coupled with about 30-40 knots of deep-layer shear (0-6km) may be enough to support some strong to marginally severe storms Tuesday afternoon. The main threats with these would be hail up to the size of quarters given seasonably low wet bulb zero heights (10-11k feet) and localized strong wind gusts. The main question on Tuesday will be the exact timing of the upper-level disturbance and the degree of which we are able to destabilize ahead of it. The remainder of the long term will be characterized by the upper-level flow flattening out just a bit, allowing a frontal boundary to stall somewhere near or over the region Wednesday into the upcoming weekend. Subtle disturbances riding along this boundary will lead to rounds of showers and thunderstorms, some of which could be overnight. The location of the boundary will be key as a more southern location (like the 28/12Z GEM) solution would dry out the northern CWA, while a more northern location 28/12Z GFS/ECMWF/GEFS would keep much of the CWA in play for these rounds of storms. Given the general agreement of the latter models, will side on the wetter side of things keeping 40-60 pops in Wednesday through Saturday. It certainly won`t rain this whole time, but the pattern will favor progressive storm systems through the region. Given how wet we have become over the past week or two, flooding may become a concern once again especially if the boundary ends up stalling over the Ohio Valley for an extended period of time. && .AVIATION (00Z TAF Update)... Issued at 740 PM EDT Sun Jun 28 2015 A quick moving low pressure system will push through the Ohio Valley late tonight into tomorrow. This system will bring showers to all TAF sites late tonight...probably more numerous at SDF/LEX late tonight into tomorrow morning. Instability overnight into the morning hours won`t be great so will not include a thunder mention in the TAFs at this point. Winds will shift from WSW to S overnight. The forecast for tomorrow isn`t real clear due to the timing of the low pressure system through Ohio Valley. Current obs/trends indicate it`s moving faster than some of the 12Z models indicate. Thus, will side with the faster HRRR and 18Z NAM. This should largely end showery activity at SDF during the morning hours with perhaps a period of MVFR cigs during the later morning hours. LEX may experience these MVFR cigs as well but the signal in the models isn`t as strong there. The cold front associated with this low pressure system should layout somewhere over central KY or northern TN for tomorrow afternoon. It`s unclear exactly where that location will be at this time, so will include VCSH at BWG/LEX which will be closest to the boundary. Will need to watch the front`s progression in coming TAF issuances to better define timing and if a thunder mention should be included in some of the TAFs for tomorrow afternoon/evening. Winds will be gusty tomorrow afternoon between 20-25 kts. The fropa should shift winds from SSW to WSW early tomorrow afternoon. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........AMS Short Term.....RAS Long Term......KJD Aviation.......AMS
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
511 AM CDT SAT JUN 27 2015 .DISCUSSION... A WEAK COOL FRONT HAS SHOWN A LITTLE BETTER DEFINITION IN THE EARLY MORNING SFC ANALYSIS...EXTENDING FROM THE NRN SECTIONS OF THE DFW METROPLEX...TO JUST S OF A PRX...TO DEQ...TO N OF A LIT...TO JBR LINE AS OF 09Z. CONVECTION RIDING A SE MOVING OUTFLOW BNDRY EARLY THIS MORNING HAS SINCE WANED AS IT PUSHES INTO SE AR/NE LA ATTM...ALTHOUGH SCT CONVECTION HAS REDEVELOPED FARTHER W OVER NE TX JUST SE OF THE FRONT...ALONG THE LEADING EDGE OF THE UPPER TROUGH AXIS EXTENDING FROM LAKE MI SW ACROSS THE MID MS VALLEY INTO NE AND SCNTRL TX. THE SHORT TERM PROGS DID NOT INITILIZE WELL ON THE ONGOING CONVECTION EARLY THIS MORNING...WITH THE HRRR HAVING TO PLAY CATCHUP WITH THE CURRENT CONVECTION...AND HINTS THAT IT SHOULD DEVELOP FARTHER ESE ALONG THE UPPER TROUGH AXIS AND NEAR/JUST S OF THE ATTENDENT H850 TROUGH. GIVEN THE WEAK SHEAR...THIS CONVECTION MAY TEND TO BE MORE OUTFLOW DOMINANT AND WEAKEN LATER THIS MORNING...WITH ADDITIONAL REDEVELOPMENT POSSIBLE ONCE SFC HEATING COMMENCES. CAN/T RULE OUT LOCALIZED HEAVY RAIN IN THE STRONGER STORMS GIVEN PW/S IN EXCESS OF 2 INCHES...AND AN ABNORMALLY DEEP WARM LAYER EVIDENT ON THE 27/00Z KSHV RAOB /WITH THE FZL NEAR 16.1 KFT/...BUT THIS THREAT SHOULD DIMINISH BY AFTERNOON AS THE AIR MASS TO THE S IS WORKED OVER FROM THE MORNING CONVECTION. DID MAINTAIN LIKELY POPS FOR AREAS ALONG/S OF I-20...TAPERING POPS BACK TO CHANCE CLOSER TO THE I-20 CORRIDOR FOR THE AFTERNOON. THERE STILL REMAINS SOME UNCERTAINTY AS TO HOW FAR S THE WEAK FRONT WILL MIX TODAY...WITH THE GFS RATHER BULLISH IN MIXING IT S TO NEAR THE I-10 CORRIDOR OF SE TX/S LA BY SUNDAY MORNING. MEANWHILE...CONSCENSUS AMONGST THE WRF/ECMWF SUGGEST THE FRONT SLOWLY NEARING THE I-20 CORRIDOR OF E TX/N LA LATE THIS AFTERNOON...BEFORE WASHING OUT LATER TONIGHT. IN ANY CASE...THE CONVECTION SHOULD CONTINUE TO BUILD S ACROSS THE REMAINDER OF THE REGION TODAY...WITH DRIER AIR ENTRAINING S BEHIND THE UPPER TROUGH AXIS LATE TODAY/THIS EVENING...THUS TAPERING THE CONVECTION OFF FROM N TO S. GIVEN THIS...HAVE SCALED BACK POPS SLIGHTLY TONIGHT...WITH THE WRF/GFS SUGGESTING THE H850 TROUGH PULLING UP STATIONARY JUST S OF I-20. STILL CAN/T RULE OUT ISOLATED CONVECTION DEVELOPING SUNDAY MAINLY OVER DEEP E TX/SRN SECTIONS OF NCNTRL LA...WITH THE WEAK H850 TROUGH EXPECTED TO WASH OUT BY AFTERNOON. TEMPS SUNDAY SHOULD BE NEAR CLIMO...WITH A LIGHT SSW SFC FLOW RETURNING MONDAY RESULTING IN HIGHER HUMIDITIES AND SLIGHTLY HIGHER TEMPS. THE UPPER LEVEL PATTERN DOESN/T APPEAR TO CHANGE FOR MUCH OF NEXT WEEK...WITH NW FLOW DOMINANT THROUGH MUCH OF THE PERIOD AHEAD OF THE MAMOUTH UPPER RIDGING OVER THE GREAT BASIN/MUCH OF THE ROCKIES. THE PROGS DO SUGGEST THE NEXT SHORTWAVE WITHIN THE NW FLOW ALOFT SLIDING S TOWARDS THE RED RIVER VALLEY MONDAY AFTERNOON...WHILE THE PARENT SHORTWAVE SWINGS SE ACROSS LOWER MI INTO THE OHIO VALLEY. DEEP LAYER MOISTURE DOESN/T APPEAR SUFFICIENT FOR ANYTHING MORE THAN SLIGHT CHANCE POPS MONDAY...ALTHOUGH INCREASING MOISTURE ADVECTION FROM THE S MAY RESULT IN AT LEAST WIDELY SCT CONVECTION TUESDAY AS THE RESIDUAL TROUGH AXIS SLOWLY SETTLES FARTHER S. AFTERWARDS...ANY CONVECTION APPEARS TO BE ISOLATED AS THE WRN COUS RIDGE WEAKENS SLIGHTLY AND BEGINS TO RETROGRADE W...WHILE THE BROADING TROUGH ALOFT BECOMES DISPLACED FARTHER NNE AWAY FROM THE REGION. THUS...MAINTAINED LOW POPS THROUGH THE REMAINDER OF THE EXTENDED FOR THE NRN ZONES...WHILE SFC-H700 RIDGING BUILDS NW FROM THE NRN GULF INTO LA...WITH THE RESULTING SUBSIDENCE LIMITING CHANCES FOR ISOLATED CONVECTION. THE ONLY EXCEPTION COULD BE DEEP E TX/WCNTRL LA...WHICH MAY SEE WEAK SEABREEZE CONVECTION BUILD N TOWARDS THE END OF THE PERIOD. TEMPS SHOULD ALSO REMAIN NEAR/JUST ABOVE CLIMO THROUGH MUCH OF NEXT WEEK AS WELL. PRELIMS TO FOLLOW BELOW... 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 88 71 90 71 / 60 10 0 0 MLU 87 69 90 69 / 60 20 0 0 DEQ 87 65 88 66 / 5 0 0 0 TXK 88 67 89 69 / 20 5 0 0 ELD 86 66 89 67 / 30 5 0 0 TYR 88 70 90 71 / 60 10 0 0 GGG 88 70 90 71 / 60 10 0 0 LFK 89 73 92 73 / 60 30 20 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
257 PM EDT SAT JUN 27 2015 .SYNOPSIS... RAINY AND COOL AS AN UNSEASONABLY DEEP LOW PRESSURE SYSTEM MOVES THROUGH THE REGION. && .NEAR TERM /THROUGH SUNDAY/... CURRENT RADAR IMAGERY SHOWS THE SYSTEM PLAYING OUT AS EXPECTED THROUGH EARLY AFTERNOON AS THE STEADY LIGHT TO MODERATE RAIN IS BEGINNING TO PUSH NORTHEAST OF THE FORECAST AREA. RAINFALL AMOUNTS FROM THIS MORNING THROUGH ABOUT NOON HAVE BEEN AROUND AN INCH WITH SOME LOCALIZED AREAS NEARING 1.5 INCHES. AS A RESULT...STORM TOTALS THUS FAR HAVE BEEN SLIGHTLY LESS THAN EARLIER INDICATIONS...AND THE AREA CREEKS AND STREAMS HAVE LARGELY BEHAVED. SOME MINOR FLOODING OF LOW SPOTS AND BASEMENTS IN ALLEGHENY/LAWRENCE/WESTMORELAND COUNTIES EARLIER MEANT A FLOOD ADVISORY WAS PRUDENT. THE WARM FRONT IS NEARING THE MASON-DIXON LINE AND PUSHING NORTH AND TAKING THE STEADY RAIN WITH IT. THE FOCUS NOW SHIFTS WEST TO THE THIN LINE ON RADAR INDICATING THE COLD FRONT. TO THIS POINT...AN ABUNDANCE OF CLOUDS HAS KEPT THE AREA AHEAD OF THE COLD FRONT STABLE...BUT SOME BREAKS IN THE CLOUD COVER HAVE DEVELOPED OVER EASTERN OHIO. SHOWERS ALONG THE COLD FRONT ARE MORE CELLULAR IN NATURE AND IF THEY CAN TAP INTO ANY AVAILABLE BOUYANCY...HAVE MORE THAN ENOUGH UPPER SUPPORT TO DEVELOP INTO STRONG OR SEVERE THUNDERSTORMS. CURRENT RAP ANALYSIS DEPICTS 500-1000J/KG SB CAPE NOSING INTO THE SOUTHERN PERIPHERY OF THE FORECAST AREA. THIS IS COLLOCATED WITH A STRENGTHENING UPPER-LEVEL JET PUSHING THROUGH THE UPPER OHIO VALLEY. WILL CONTINUE TO MONITOR THE THREAT FOR SEVERE WEATHER IN THE FORM OF DAMAGING WINDS AND AN ISOLATED TORNADO THROUGH THE EVENING HOURS FROM THE NORTHERN PANHANDLE OF WV THROUGH SOUTHWEST PA...NORTHERN WV AND WESTERN MARYLAND. WATER VAPOR IMAGERY SHOWING THE DRY SLOT ADVANCING AHEAD OF THE LOW...RESULTING IN SOME DRYING OF THE COLUMN. THE MOST IMPRESSIVE 850MB MOISTURE TRANSPORT IS NOW NORTHEAST OF THE AREA AS THE MID- LEVEL FLOW TAPS INTO THE ATLANTIC OCEAN FOR MOISTURE. STILL...PW VALUES OF GREATER THAN 1.5" RESIDE ACROSS THE BULK OF THE FORECAST AREA. ANY RE-DEVELOPMENT ALONG THE COLD FRONT COULD TAP THE DEEPER MOISTURE RESULTING IN EFFICIENT RAIN PRODUCERS. WITH A BASE COAT OF AROUND AN INCH OF RAIN ALREADY IN THE AREAS SOILS...HAVE DECIDED TO KEEP THE FLOOD WATCH UP THIS AFTERNOON. THE SYSTEM BEGINS TO OCCLUDE TONIGHT AND MOVES TO THE NORTH OF THE FORECAST AREA BY DAYBREAK SUNDAY. WRAP-AROUND MOISTURE WILL KEEP THE THREAT OF LIGHT RAIN SHOWERS IN THE FORECAST THROUGH SUNDAY...BUT SHOULD RESULT IN LITTLE MORE THAN AN ADDITIONAL ONE TO TWO TENTHS OF AN INCH. TEMPERATURES WILL BE WELL BELOW AVERAGE THROUGH THE WEEKEND AS THE NORTHWEST UPPER-LEVEL FLOW BEHIND THE FRONT RE-ENFORCES THE COOL AIR. TAX && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... THE UPPER LOW WILL CONTINUE TO TRUDGE OFF TO THE NORTH AND EAST SUNDAY NIGHT. THIS ALONG WITH DIURNAL STABILIZATION WILL ALLOW REMAINING SHRA TO END. TRANSIENT AND SMALL MIDLEVEL AND SURFACE RIDGING WILL KEEP THE CWA MOSTLY DRY LATER SUNDAY NIGHT AND MONDAY MORNING. YET ANOTHER SHORTWAVE WILL DIG INTO THE WESTERN GREAT LAKES BY MONDAY AFTERNOON...WITH A SURFACE LOW PASSING NEAR DETRIOT BY 12Z TUESDAY. THE NAM APPEARS TO BE A STRONG AND FAST OUTLIER AS COMPARED TO THE GFS AND ECMWF. WITH THE LESS DYNAMIC SYSTEM AND LOWER MOISTURE AVAILABILITY (PWATS BELOW 1.5 INCHES)...THE SYSTEM WILL NOT BE ABLE TO MANAGE RAINFALL AMOUNTS SIMILAR TO TODAY. SLOWED POPS A BIT MONDAY AFTERNOON...BUT WILL MAINTAIN LIKELY VALUES FOR MONDAY NIGHT. THINK QPF FROM THIS SYSTEM WILL REMAIN BELOW 0.5 INCH IN GENERAL. TIMING OF SYSTEM IS NOT FAVORABLE FOR SEVERE WEATHER...DESPITE THE STRONG FLOW PATTERN. THIS SYSTEM PULLS AWAY BY TUESDAY MORNING...BUT EXPECT THREAT OF SHRA AND A FEW TSRA TO CONTINUE THROUGH THE DAY...ESPECIALLY IN THE AFTERNOON AS LOW LEVEL LAPSE RATES STEEPEN. AFTER THE COOL TEMPERATURES SUNDAY...VALUES REBOUND TOWARDS SEASONABLE LEVELS MONDAY AFTERNOON. MORE ABUNDANT CLOUDS TUESDAY WILL COOL VALUES A FEW DEGREES FOR AFTERNOON HIGHS. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... MODEL GUIDANCE FAVORS INCREASED RIDGING IN THE WEST WITH DOWNSTREAM DEEPENING TROUGHING ACROSS THE GREAT LAKES. THIS WILL LIKELY KEEP THINGS FAIRLY ACTIVE AND WET OVER THE CWA...WITH TEMPERATURES LIKELY TO REMAIN BELOW NORMAL. MONDAY NIGHT INTO TUESDAY SEES THE BEST SHOT AT WIDESPREAD RAIN SHOWERS ACROSS THE AREA. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... RAIN WILL TAPER OFF THROUGH THIS AFTERNOON WITH IFR CONDITIONS LIFTING TO MVFR CIG RESTRICTIONS. MOST TERMINALS SHOULD SEE A BREAK IN THE PRECIPITATION BY THIS LATE AFTERNOON AND IMPROVE TO VFR. A DRY SLOT IS MOVING IN WITH BREAKS IN THE CLOUDS THAT WILL ALLOW ADDITIONAL SURFACE HEATING FOR THE REMAINDER OF TODAY. THE HEATING OF RESIDUAL MOISTURE WILL AID IN DEVELOPMENT OF THUNDERSTORMS DURING THE LATE AFTERNOON INTO THIS EVENING. EXPECTING IFR CIGS CONDITIONS TO RETURN BY SUNDAY AM WITH -RA/DZ. .OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/... RESTRICTIONS ARE LIKELY THROUGH THE REST OF THE WEEKEND WITH PASSAGE OF A STRONG LOW PRESSURE SYSTEM. AN APPROACHING COLD FRONT MAY CAUSE POSSIBLE RESTRICTIONS WITH RAIN MONDAY AND TUESDAY. && .HYDROLOGY... THE COLD FRONT IS JUST TO OUR WEST AND WILL SLOWLY TRACK RAIN SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA THROUGH THE REMAINDER OF SATURDAY. AT THIS TIME... LOCALIZED URBAN AND SMALL STREAM FLOODING HAS BEEN REPORTED ACROSS THE REGION... HOWEVER WE ARE NOT EXPECTING SHARP RISES ON THE MAIN STEM RIVERS AT THIS TIME. THE TRACK OF THE SYSTEM HAS THE UPPER LOW PRESSURE CENTERED OVER DETROIT AND SLOWLY MOVING OFF TO THE NORTHEAST. OVER THE PAST 24 HOURS OUR CWA HAS RECEIVED FROM ONE-QUARTER /0.25/ TO JUST UNDER 2 /2.00/ INCHES OF RAINFALL WITH THE HIGHER AMOUNTS FALLING IN THE RIDGES OF WESTMORELAND AND TUCKER COUNTIES. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR MDZ001. OH...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR OHZ039>041- 048>050-057>059-068-069. PA...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR PAZ014-020>023- 029-031-073>076. FLOOD WATCH UNTIL 2 AM EDT SUNDAY FOR PAZ007>009-013-015-016. WV...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR WVZ001>004-012- 021>023-041. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
222 PM EDT SAT JUN 27 2015 .SYNOPSIS... RAINY AND COOL AS AN UNSEASONABLY DEEP LOW PRESSURE SYSTEM MOVES THROUGH THE REGION. && .NEAR TERM /THROUGH SUNDAY/... CURRENT RADAR IMAGERY SHOWS THE SYSTEM PLAYING OUT AS EXPECTED THROUGH EARLY AFTERNOON AS THE STEADY LIGHT TO MODERATE RAIN IS BEGINNING TO PUSH NORTHEAST OF THE FORECAST AREA. RAINFALL AMOUNTS FROM THIS MORNING THROUGH ABOUT NOON HAVE BEEN AROUND AN INCH WITH SOME LOCALIZED AREAS NEARING 1.5 INCHES. AS A RESULT...STORM TOTALS THUS FAR HAVE BEEN SLIGHTLY LESS THAN EARLIER INDICATIONS...AND THE AREA CREEKS AND STREAMS HAVE LARGELY BEHAVED. SOME MINOR FLOODING OF LOW SPOTS AND BASEMENTS IN ALLEGHENY/LAWRENCE/WESTMORELAND COUNTIES EARLIER MEANT A FLOOD ADVISORY WAS PRUDENT. THE WARM FRONT IS NEARING THE MASON-DIXON LINE AND PUSHING NORTH AND TAKING THE STEADY RAIN WITH IT. THE FOCUS NOW SHIFTS WEST TO THE THIN LINE ON RADAR INDICATING THE COLD FRONT. TO THIS POINT...AN ABUNDANCE OF CLOUDS HAS KEPT THE AREA AHEAD OF THE COLD FRONT STABLE...BUT SOME BREAKS IN THE CLOUD COVER HAVE DEVELOPED OVER EASTERN OHIO. SHOWERS ALONG THE COLD FRONT ARE MORE CELLULAR IN NATURE AND IF THEY CAN TAP INTO ANY AVAILABLE BOUYANCY...HAVE MORE THAN ENOUGH UPPER SUPPORT TO DEVELOP INTO STRONG OR SEVERE THUNDERSTORMS. CURRENT RAP ANALYSIS DEPICTS 500-1000J/KG SB CAPE NOSING INTO THE SOUTHERN PERIPHERY OF THE FORECAST AREA. THIS IS COLLOCATED WITH A STRENGTHENING UPPER-LEVEL JET PUSHING THROUGH THE UPPER OHIO VALLEY. WILL CONTINUE TO MONITOR THE THREAT FOR SEVERE WEATHER IN THE FORM OF DAMAGING WINDS AND AN ISOLATED TORNADO THROUGH THE EVENING HOURS FROM THE NORTHERN PANHANDLE OF WV THROUGH SOUTHWEST PA...NORTHERN WV AND WESTERN MARYLAND. WATER VAPOR IMAGERY SHOWING THE DRY SLOT ADVANCING AHEAD OF THE LOW...RESULTING IN SOME DRYING OF THE COLUMN. THE MOST IMPRESSIVE 850MB MOISTURE TRANSPORT IS NOW NORTHEAST OF THE AREA AS THE MID- LEVEL FLOW TAPS INTO THE ATLANTIC OCEAN FOR MOISTURE. STILL...PW VALUES OF GREATER THAN 1.5" RESIDE ACROSS THE BULK OF THE FORECAST AREA. ANY RE-DEVELOPMENT ALONG THE COLD FRONT COULD TAP THE DEEPER MOISTURE RESULTING IN EFFICIENT RAIN PRODUCERS. WITH A BASE COAT OF AROUND AN INCH OF RAIN ALREADY IN THE AREAS SOILS...HAVE DECIDED TO KEEP THE FLOOD WATCH UP THIS AFTERNOON. THE SYSTEM BEGINS TO OCCLUDE TONIGHT AND MOVES TO THE NORTH OF THE FORECAST AREA BY DAYBREAK SUNDAY. WRAP-AROUND MOISTURE WILL KEEP THE THREAT OF LIGHT RAIN SHOWERS IN THE FORECAST THROUGH SUNDAY...BUT SHOULD RESULT IN LITTLE MORE THAN AN ADDITIONAL ONE TO TWO TENTHS OF AN INCH. TEMPERATURES WILL BE WELL BELOW AVERAGE THROUGH THE WEEKEND AS THE NORTHWEST UPPER-LEVEL FLOW BEHIND THE FRONT RE-ENFORCES THE COOL AIR. TAX && .SHORT TERM /SUNDAY NIGHT THROUGH MONDAY/... SHOWERS AND COOLER TEMPERATURES CAN BE EXPECTED TONIGHT AND THROUGH MUCH OF SUNDAY. SYSTEM FINALLY EXITS EARLY MONDAY AND THERE WILL BE A SHORT REPRIEVE IN THE ACTIVE WEATHER. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... MODEL GUIDANCE FAVORS INCREASED RIDGING IN THE WEST WITH DOWNSTREAM DEEPENING TROUGHING ACROSS THE GREAT LAKES. THIS WILL LIKELY KEEP THINGS FAIRLY ACTIVE AND WET OVER THE CWA...WITH TEMPERATURES LIKELY TO REMAIN BELOW NORMAL. MONDAY NIGHT INTO TUESDAY SEES THE BEST SHOT AT WIDESPREAD RAIN SHOWERS ACROSS THE AREA. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... RAIN WILL TAPER OFF THROUGH THIS AFTERNOON WITH IFR CONDITIONS LIFTING TO MVFR CIG RESTRICTIONS. MOST TERMINALS SHOULD SEE A BREAK IN THE PRECIPITATION BY THIS LATE AFTERNOON AND IMPROVE TO VFR. A DRY SLOT IS MOVING IN WITH BREAKS IN THE CLOUDS THAT WILL ALLOW ADDITIONAL SURFACE HEATING FOR THE REMAINDER OF TODAY. THE HEATING OF RESIDUAL MOISTURE WILL AID IN DEVELOPMENT OF THUNDERSTORMS DURING THE LATE AFTERNOON INTO THIS EVENING. EXPECTING IFR CIGS CONDITIONS TO RETURN BY SUNDAY AM WITH -RA/DZ. .OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/... RESTRICTIONS ARE LIKELY THROUGH THE REST OF THE WEEKEND WITH PASSAGE OF A STRONG LOW PRESSURE SYSTEM. AN APPROACHING COLD FRONT MAY CAUSE POSSIBLE RESTRICTIONS WITH RAIN MONDAY AND TUESDAY. && .HYDROLOGY... THE COLD FRONT IS JUST TO OUR WEST AND WILL SLOWLY TRACK RAIN SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA THROUGH THE REMAINDER OF SATURDAY. AT THIS TIME... LOCALIZED URBAN AND SMALL STREAM FLOODING HAS BEEN REPORTED ACROSS THE REGION... HOWEVER WE ARE NOT EXPECTING SHARP RISES ON THE MAIN STEM RIVERS AT THIS TIME. THE TRACK OF THE SYSTEM HAS THE UPPER LOW PRESSURE CENTERED OVER DETROIT AND SLOWLY MOVING OFF TO THE NORTHEAST. OVER THE PAST 24 HOURS OUR CWA HAS RECEIVED FROM ONE-QUARTER /0.25/ TO JUST UNDER 2 /2.00/ INCHES OF RAINFALL WITH THE HIGHER AMOUNTS FALLING IN THE RIDGES OF WESTMORELAND AND TUCKER COUNTIES. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR MDZ001. OH...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR OHZ039>041- 048>050-057>059-068-069. PA...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR PAZ014-020>023- 029-031-073>076. FLOOD WATCH THROUGH LATE TONIGHT FOR PAZ007>009-013-015-016. WV...FLOOD WATCH UNTIL 5 PM EDT THIS AFTERNOON FOR WVZ001>004-012- 021>023-041. && $$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
133 PM EDT SAT JUN 27 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 328 AM EDT SAT JUN 27 2015 AN UNSEASONABLY STRONG STORM SYSTEM FOR THIS TIME OF YEAR WILL TRACK ACROSS THE SOUTHERN GREAT LAKES TODAY...HEADING INTO CENTRAL NEW YORK STATE BY SUNDAY MORNING. THIS WILL BRING STRONG WINDS...LOCALLY HEAVY RAIN AND UNSEASONABLY CHILLY TEMPERATURES TO INTERSTATE 69 AREA TODAY. AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HAVE PARTLY CLOUDY SKIES AND HIGHS IN THE 70S. BY TONIGHT THE STORM WILL BE FAR ENOUGH AWAY FROM THIS AREA SO THAT SKIES SHOULD CLEAR FROM WEST TO EAST. SUNDAY SHOULD BE PARTLY SUNNY. ANOTHER STORM SYSTEM WILL BRING SHOWERS AND SCATTERED THUNDERSTORMS INTO THE AREA MONDAY. THOSE MAY LINGER INTO TUESDAY. BEHIND THAT SYSTEM CANADIAN HIGH PRESSURE BUILDS INTO THE AREA FOR MID WEEK. THAT WILL MEAN COOL TEMPERATURES FOR THIS TIME OF YEAR BUT MOSTLY CLEAR SKIES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 A RATHER UNUSUAL STORM FOR THIS TIME OF YEAR WILL TRACK THROUGH THE SOUTHERN GREAT LAKES TODAY AND OVER WESTERN LAKE ERIE TONIGHT. IT WILL BRING STRONG WINDS...CLOSE TO ADVISORY CRITERIA IN THE INTERSTATE 69 AREA WITH RAIN...HEAVY AT TIMES. BUT AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HARDLY KNOW THE STORM IS IN OUR AREA AS SKIES WILL BE PARTLY CLOUDY AND WINDS WILL NOT BE ALL THAT STRONG EITHER. THE GLITCH FOR THIS FORECAST IT TO DECIDE JUST HOW FAR WEST AND NORTH THE RAIN ACTUALLY GETS TODAY. THE GEFS CLIMATE ANOMALIES FOR THIS SYSTEM TELL THE STORY. THE SURFACE PRESSURE OF THE LOW FALLS TO BELOW 1000 MB...THAT IS NEARLY 3.5 STANDARD DEVIATIONS FROM NORMAL OR HAS A RETURN INTERVAL AT THIS TIME OF YEAR OF AROUND ONCE IN TEN YEARS. THIS IS ONE OF THOSE COUPLED JET EVENTS WITH STRONG DYNAMICS AND A LOT OF GULF MOISTURE TO WORK WITH. THE DEFORMATION ZONE OF THE SYSTEM SETS UP OVER OUR SE CWA TODAY BUT THERE IS A CONSIDERABLE AMOUNT OF LOW LEVEL DRY AIR FEEDING INTO THE SYSTEM FROM THE NORTH (BLOCKING HIGH OVER SOUTHERN CANADA). THE MODELS HAVE BE VERY INCONSISTENT WITH JUST HOW FAR WEST THE RAIN GETS. FOR NOW I AM GOING WITH A BLEND OF THE RAP MODEL AND HRRR AND CALLING THAT GOOD. WINDS WILL BE AN ISSUE WITH THIS STORM TOO...THE RAP MODEL IS SHOWING 45 TO 50 KNOTS OVER JACKSON FROM 8 AM THROUGH SUNSET JUST ABOVE THE SURFACE. THE MIXING HEIGHT TAPS INTO THIS SO I WOULD EXPECT SOME GUSTS TO BETWEEN 40 TO 45 KNOTS THIS AFTERNOON IN THAT AREA... JUST UNDER ADVISORY CRITERIA. THIS WILL HAVE TO BE WATCHED. ALL OF THIS MOVES OUT THIS EVENING. THE NEXT SYSTEM MOVES IN SUNDAY NIGHT INTO MONDAY. SINCE THE POLAR JET IS WELL SOUTH OF US BY THEN...THIS WILL BE MORE OF A SHOWERY DAY WITH ISOLATED THUNDERSTORMS IN THE AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 WE CONTINUE TO EXPECT THAT WE WILL BE UNDER THE INFLUENCE OF AN UNSETTLED WEATHER PATTERN FOR THE FIRST FEW PERIODS OF THE LONG TERM PORTION OF THE FCST. THE ANTICIPATED LONG WAVE TROUGH WILL BE OVER THE AREA FROM MON NIGHT INTO TUE NIGHT. THE BEST CHC OF RAIN WILL BEST MON NIGHT WITH A FAIRLY STOUT CLOSED SHORT WAVE AND ASSOCIATED SFC LOW PASSING THROUGH. RAIN WILL REMAIN POSSIBLE TUE AND TUE NIGHT...BUT IT DOES NOT LOOK TO BE AS WIDESPREAD WITH A WEAKER WAVE MOVING THROUGH. IT WILL ALSO BE MORE DIURNALLY FOCUSED AND AWAY FROM THE LAKE. THE TREND OVER THE PAST COUPLE OF DAYS HAS DEFINITELY BEEN FOR A DRIER PERIOD FOR THE MID PORTION OF THE WEEK FROM WED THROUGH THU. THIS OCCURS AS THE LONG WAVE TROUGH IS PUSHED EAST OF THE AREA AND WE BECOME UNDER THE INFLUENCE OF SUBSIDENCE DOWNSTREAM OF THE LONG WAVE RIDGE ACROSS THE WRN HALF OF THE CONUS. WE WILL LIKELY REMAIN A LITTLE COOLER THAN AVERAGE WITH THE NW FLOW ALOFT. THE BREAK IN THE RAIN AND QUIET WEATHER LOOKS TO BE SHORT LIVED AS THE NEXT CHC OF PCPN WILL START MAKING ITS WAY TOWARD THE AREA ON FRI. THIS OCCURS AS THE NEXT STRONGER SHORT WAVE RIDING DOWN THE WRN RIDGE WILL APPROACH FROM THE NW. THIS WILL LIKELY NOT HAVE RICH MOISTURE TO WORK WITH AS GULF MOISTURE REMAINS LOCKED UP DOWN SOUTH. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 132 PM EDT SAT JUN 27 2015 VFR CONDITIONS ARE EXPECTED THROUGH SUNDAY. THE EXCEPTIONS WILL BE SOME CEILINGS IN THE 2000 TO 300 FOOT RANGE AND VISIBILITY AROUND 3 TO 5 MILES THIS AFTERNOON IN AREAS OF HEAVIER RAIN SOUTH AND EAST OF GRR. NORTH WINDS WILL GUST OVER 20 KNOTS AT TIMES THIS AFTERNOON AND EVENING BEFORE DECREASING TO 10 KNOTS OR LESS BY 06Z TONIGHT. && .MARINE... ISSUED AT 328 AM EDT SAT JUN 27 2015 THE GOOD NEWS IS THE STORM IS JUST FAR ENOUGH TO THE SOUTH AND EAST THAT IT WILL HAVE LITTLE IMPACT ON THE NEAR SHORE WATERS. SO NO HEADLINES SEEM NEEDED AT THIS POINT. && .HYDROLOGY... ISSUED AT 1110 AM EDT SAT JUN 27 2015 RIVER FLOOD ADVISORIES REMAIN IN EFFECT AS RUNOFF OF RAINFALL MAKES ITS WAY THROUGH THE RIVER SYSTEM. RAIN ACCUMULATIONS THROUGH THE NEXT WEEK ARE EXPECTED TO BE A HALF INCH IN MOST AREAS WITH UP TO AN INCH AND A HALF IN THE SOUTH. SIGNIFICANT FLOODING IS NOT EXPECTED... BUT MINOR FLOODING ALONG RIVERS AND IN LOW-LYING AREAS MAY PERSIST THROUGH THE WEEK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...WDM SHORT TERM...WDM LONG TERM...NJJ AVIATION...OSTUNO HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION
NWS GAYLORD MI
114 PM EDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1017 AM EDT SAT JUN 27 2015 HIGH CLOUDS REMAIN THE RULE ACROSS LWR MICHIGAN LATE THIS MORNING ALONG THE NW PERIPHERY OF THE PRECIP SHIELD ASSOCIATED WITH LOW PRESSURE TRACKING NE THRU THE OHIO VALLEY. ALL PRECIP REMAINS WELL SOUTH OF OUR CWA...AND SHOULD CONTINUE TO DO SO AS WE HEAD INTO THE AFTERNOON AND EVEN THRU THE EVENING HOURS PER LATEST HRRR AND NAM12. NO CHANGES NEEDED FOR THE AFTERNOON AS SKIES REMAIN MOSTLY CLOUDY IN THE SE HALF OF OUR CWA WHERE HIGH CLOUDS WILL BE RATHER THICK. THE NW HALF OF OUR CWA WILL GENERALLY BE MOSTLY SUNNY WITH THINNER HIGH CLOUDS OVERHEAD. HIGH TEMPS IN THE 70S STILL LOOKS REASONABLE FOR THE AFTERNOON. && .NEAR TERM...(TODAY THROUGH TONIGHT) ISSUED AT 418 AM EDT SAT JUN 27 2015 ...SHOWER OR TWO EASTERN UPPER OTHERWISE MIXED SKIES TODAY... HIGH IMPACT WEATHER POTENTIAL: MINIMAL. PATTERN SYNOPSIS/FORECAST: 03Z SURFACE ANALYSIS SHOWS AN ELONGATED RIDGE AXIS THAT STRETCHES FROM THE CENTRAL HIGH PLAINS EAST ACROSS THE UPPER GREAT LAKES AND INTO SOUTHERN QUEBEC. 1008MB SURFACE LOW OVER SOUTHERN INDIANA ALONG A FRONTAL BOUNDARY THAT EXTENDS BACK INTO FAR SOUTHERN MISSOURI/EASTERN OKLAHOMA...AND A TIGHTENING PRESSURE GRADIENT BETWEEN THESE TWO FEATURES ACROSS ILLINOIS/ INDIANA/OHIO/FAR SOUTHERN LOWER MICHIGAN. DEEP LAYER/WEAK EASTERLY FLOW ACROSS NORTHERN LOWER MICHIGAN WITH A CIRROSTRATUS DECK OVERHEAD...AND NORTHERN EDGE OF A RAIN SHIELD LIFTING NORTH TOWARD THE I-96 CORRIDOR. INDIANA SURFACE LOW EXPECTED TO LIFT NORTHEAST SLOWLY TOWARD LAKE ERIE DURING THE DAY TODAY...WHILE WEAK SURFACE RIDGE AXIS HANGS ON RATHER STUBBORNLY THROUGH TONIGHT. SURFACE LOW OCCLUDES OVERNIGHT AND SLOWS WHILE SECONDARY DEVELOPMENT OCCURS ALONG THE MID ATLANTIC COAST. PRIMARY FORECAST CONCERNS: NORTHERN EXTENT OF RAIN SHIELD ASSOCIATED WITH OHIO VALLEY SYSTEM. POTENTIAL FOR DIURNAL SHOWERS ACROSS UPPER MICHIGAN AND ADJACENT AREAS OF NORTHERN ONTARIO THIS AFTERNOON. TODAY...LOOKS TO BE REAL CLOSE IN TERMS OF HOW FAR NORTHERN EDGE OF PRECIPITATION SHIELD REACHES INTO CENTRAL LOWER MICHIGAN...WITH DOWNWARD BRANCH OF MID LEVEL FRONTOGENESIS MAXIMUM HELPING KEEP PRECIPITATION FROM REACHING TOO FAR INTO THE FORECAST AREA. COULD SEE SOME LIGHT PRECIP SCRAPING PARTS OF GLADWIN/ARENAC/IOSCO COUNTIES. MEANWHILE...AXIS OF WEAK INSTABILITY DEVELOPS WITH HEATING ACROSS UPPER MICHIGAN AND ADJACENT AREAS OF ONTARIO THIS AFTERNOON. COLLIDING LAKE BREEZES EXPECTED AGAIN OVER EASTERN UPPER...WHICH COULD KICK OFF SOME SPOTTY HIGH BASED SHOWERS (MOST HIGH RESOLUTION GUIDANCE SUPPORTS THIS IDEA). OTHERWISE ANOTHER SEASONABLY MILD DAY EXPECTED WITH HIGH TEMPERATURES MAINLY IN THE 70S (COOLER NEAR LAKE HURON IN NORTHEAST LOWER WITH MORE CLOUDS AND ONSHORE WINDS). WINDS WILL BE GUSTIER TODAY THE FARTHER SOUTH (ACTUALLY SOUTHEAST) ONE GOES TODAY (NORTHEAST GUSTS 20-30MPH). TONIGHT...QUIET AGAIN TONIGHT WITH MORE CLOUDS ACROSS NORTHEAST LOWER IN PROXIMITY TO OCCLUDING SURFACE LOW OVER THE LOWER GREAT LAKES. TEMPERATURES MOSTLY NEAR CLIMATOLOGICAL NORMALS (AROUND 50 TO THE MID 50S EXPECTED FOR SUNDAY MORNING LOWS). && .SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT) ISSUED AT 418 AM EDT SAT JUN 27 2015 MODELS ARE COMING INTO AGREEMENT WITH HINTING AT SOME DIURNAL SHOWER POTENTIAL OR EVEN A RUMBLE OF THUNDER OVER THE INLAND AREAS OF NORTHERN LOWER MICHIGAN DURING THE LATE AFTERNOON AND EARLY EVENING HOURS SUNDAY. A THIN RIBBON OF MID-LEVEL MOISTURE ADVECTING IN FROM NORTHERLY WINDS BEHIND THE DEPARTING LOW PRESSURE SYSTEM OVER THE NORTHEASTERN U.S. ALONG WITH CONVERGENCE FROM LAKE BREEZE BOUNDARIES MAY BE JUST ENOUGH TO FIRE SOME OFF. MOST MODELS HAVE 600 TO 800 J/KG OF MUCAPE...JUST NEED THE TRIGGER (SOMETHING NORTHERN MICHIGAN SEEMS TO LACK QUITE A BIT). AS THE PREVIOUS FORECASTER MENTIONED...WILL CONTINUE TO LEAVE THIS SLIGHT CHANCE OF PRECIPITATION OUT UNTIL GREATER CONFIDENCE IS REALIZED AND MAKE SURE CURRENT MODEL TRENDS CONTINUE. BESIDES THE SLIGHT CHANCES OF DIURNAL SHOWERS/THUNDER...SUNDAY WILL BE A NICE SUMMER DAY WITH HIGHS IN THE MID TO UPPER 70S...LIGHT WINDS...AND MOSTLY CLEAR/PARTLY CLOUDY SKIES FOR MOST OF THE DAY. SYNOPTIC MOISTURE FROM THE NEXT WAVE APPROACHING FROM THE WEST WILL BEGIN IMPACTING NORTHERN MICHIGAN WITH INCREASED CLOUDINESS SUNDAY NIGHT THROUGH MONDAY AND THEN PRECIPITATION CHANCES DON/T ENTER THE FORECAST UNTIL THE AFTERNOON HOURS (TRENDING A BIT SLOWER WITH EACH RUN) AND LAST THROUGH THE NIGHT. A RIDGE OF HIGH PRESSURE ALONG WITH A DRIER ATMOSPHERE APPEAR TO HOLD OFF THE ONSET OF PRECIPITATION UNTIL LATER IN THE DAY AS THE UPPER LEVEL TROUGH AND VERY WEAK SURFACE REFLECTION MOVE OVERHEAD...RETURNING SOUTHERLY FLOW AND PWAT VALUES OF BETWEEN 1.00 AND 1.50 INCHES. RAIN WILL BEGIN OVER NORTHWEST LOWER MICHIGAN MONDAY AFTERNOON AND SPREAD EASTWARD INTO THE LATE AFTERNOON/EARLY EVENING HOURS. LOW TEMPERATURES MONDAY MORNING WILL BE IN THE 50S....WHILE HIGH TEMPERATURES MONDAY AFTERNOON WILL BE SLIGHTLY COOLER THAN SUNDAY/S...IN THE LOW TO MID 70S. && .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 418 AM EDT SAT JUN 27 2015 POSITIVE PNA CONTINUES A RATHER PROGRESSIVE WEATHER PATTERN OVER THE GREAT LAKES REGION WITH A SERIES OF SHORTWAVE TROUGHS AND WEAK SURFACE LOWS TREKKING THROUGH...BRINGING CHANCES OF PRECIPITATION FOR MUCH OF THE PERIOD...WITH BRIEF PERIODS OF PRECIPITATION-FREE WEATHER IN BETWEEN EACH EVENT. DUE TO THE UNSETTLED WEATHER PATTERN THERE REMAINS MUCH UNCERTAINTY IN TIMING AND EXACT LOCATION OF EACH EVENT. DAYTIME HIGHS SHOULD REMAIN IN THE MID 60S TO MID 70S WITH LOWS IN THE UPPER 40S TO MID 50S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 113 PM EDT SAT JUN 27 2015 SOLID VFR CONDITIONS WILL CONTINUE AT ALL NRN LWR MICHIGAN TAF SITES THRU SUNDAY AS HIGH PRESSURE AND DRY AIR REMAIN LOCKED OVERHEAD. NE WINDS AOB 10 KTS THIS AFTERNOON/EVENING WILL BECOME LIGHT/CALM AFTER SUNSET...AND WILL THEN SHIFT TO THE W/NW AOB 10 KTS ON SUNDAY. && .MARINE... ISSUED AT 418 AM EDT SAT JUN 27 2015 TODAY/TONIGHT...NORTHERN EDGE OF A TIGHTER PRESSURE GRADIENT ASSOCIATED WITH A SURFACE LOW MOVING NORTHEAST ACROSS OHIO WILL SPREAD ACROSS SOUTHERN LAKE HURON TODAY...WITH INCREASING NORTHEAST WINDS AS A RESULT FROM THUNDER BAY SOUTH TO SAGINAW BAY. SMALL CRAFT ADVISORIES WILL LIKELY BE NECESSARY IN THESE NEARSHORE AREAS PROBABLY INTO THIS EVENING. MEANWHILE...LIGHTER WINDS EXPECTED FOR THE NEARSHORE ZONES AROUND THE EASTERN U.P. WITH LAKE BREEZES LIKELY. OUTLOOK...NO ADDITIONAL MARINE HAZARDS ANTICIPATED THROUGH SUNDAY NIGHT. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SUNDAY FOR LHZ349. LM...NONE. LS...NONE. && $$ UPDATE...MLR NEAR TERM...JPB SHORT TERM...TJL LONG TERM...TJL AVIATION...MLR MARINE...JPB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1110 AM EDT SAT JUN 27 2015 LATEST UPDATE... HYDRO .SYNOPSIS... ISSUED AT 328 AM EDT SAT JUN 27 2015 AN UNSEASONABLY STRONG STORM SYSTEM FOR THIS TIME OF YEAR WILL TRACK ACROSS THE SOUTHERN GREAT LAKES TODAY...HEADING INTO CENTRAL NEW YORK STATE BY SUNDAY MORNING. THIS WILL BRING STRONG WINDS...LOCALLY HEAVY RAIN AND UNSEASONABLY CHILLY TEMPERATURES TO INTERSTATE 69 AREA TODAY. AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HAVE PARTLY CLOUDY SKIES AND HIGHS IN THE 70S. BY TONIGHT THE STORM WILL BE FAR ENOUGH AWAY FROM THIS AREA SO THAT SKIES SHOULD CLEAR FROM WEST TO EAST. SUNDAY SHOULD BE PARTLY SUNNY. ANOTHER STORM SYSTEM WILL BRING SHOWERS AND SCATTERED THUNDERSTORMS INTO THE AREA MONDAY. THOSE MAY LINGER INTO TUESDAY. BEHIND THAT SYSTEM CANADIAN HIGH PRESSURE BUILDS INTO THE AREA FOR MID WEEK. THAT WILL MEAN COOL TEMPERATURES FOR THIS TIME OF YEAR BUT MOSTLY CLEAR SKIES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 A RATHER UNUSUAL STORM FOR THIS TIME OF YEAR WILL TRACK THROUGH THE SOUTHERN GREAT LAKES TODAY AND OVER WESTERN LAKE ERIE TONIGHT. IT WILL BRING STRONG WINDS...CLOSE TO ADVISORY CRITERIA IN THE INTERSTATE 69 AREA WITH RAIN...HEAVY AT TIMES. BUT AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HARDLY KNOW THE STORM IS IN OUR AREA AS SKIES WILL BE PARTLY CLOUDY AND WINDS WILL NOT BE ALL THAT STRONG EITHER. THE GLITCH FOR THIS FORECAST IT TO DECIDE JUST HOW FAR WEST AND NORTH THE RAIN ACTUALLY GETS TODAY. THE GEFS CLIMATE ANOMALIES FOR THIS SYSTEM TELL THE STORY. THE SURFACE PRESSURE OF THE LOW FALLS TO BELOW 1000 MB...THAT IS NEARLY 3.5 STANDARD DEVIATIONS FROM NORMAL OR HAS A RETURN INTERVAL AT THIS TIME OF YEAR OF AROUND ONCE IN TEN YEARS. THIS IS ONE OF THOSE COUPLED JET EVENTS WITH STRONG DYNAMICS AND A LOT OF GULF MOISTURE TO WORK WITH. THE DEFORMATION ZONE OF THE SYSTEM SETS UP OVER OUR SE CWA TODAY BUT THERE IS A CONSIDERABLE AMOUNT OF LOW LEVEL DRY AIR FEEDING INTO THE SYSTEM FROM THE NORTH (BLOCKING HIGH OVER SOUTHERN CANADA). THE MODELS HAVE BE VERY INCONSISTENT WITH JUST HOW FAR WEST THE RAIN GETS. FOR NOW I AM GOING WITH A BLEND OF THE RAP MODEL AND HRRR AND CALLING THAT GOOD. WINDS WILL BE AN ISSUE WITH THIS STORM TOO...THE RAP MODEL IS SHOWING 45 TO 50 KNOTS OVER JACKSON FROM 8 AM THROUGH SUNSET JUST ABOVE THE SURFACE. THE MIXING HEIGHT TAPS INTO THIS SO I WOULD EXPECT SOME GUSTS TO BETWEEN 40 TO 45 KNOTS THIS AFTERNOON IN THAT AREA... JUST UNDER ADVISORY CRITERIA. THIS WILL HAVE TO BE WATCHED. ALL OF THIS MOVES OUT THIS EVENING. THE NEXT SYSTEM MOVES IN SUNDAY NIGHT INTO MONDAY. SINCE THE POLAR JET IS WELL SOUTH OF US BY THEN...THIS WILL BE MORE OF A SHOWERY DAY WITH ISOLATED THUNDERSTORMS IN THE AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 WE CONTINUE TO EXPECT THAT WE WILL BE UNDER THE INFLUENCE OF AN UNSETTLED WEATHER PATTERN FOR THE FIRST FEW PERIODS OF THE LONG TERM PORTION OF THE FCST. THE ANTICIPATED LONG WAVE TROUGH WILL BE OVER THE AREA FROM MON NIGHT INTO TUE NIGHT. THE BEST CHC OF RAIN WILL BEST MON NIGHT WITH A FAIRLY STOUT CLOSED SHORT WAVE AND ASSOCIATED SFC LOW PASSING THROUGH. RAIN WILL REMAIN POSSIBLE TUE AND TUE NIGHT...BUT IT DOES NOT LOOK TO BE AS WIDESPREAD WITH A WEAKER WAVE MOVING THROUGH. IT WILL ALSO BE MORE DIURNALLY FOCUSED AND AWAY FROM THE LAKE. THE TREND OVER THE PAST COUPLE OF DAYS HAS DEFINITELY BEEN FOR A DRIER PERIOD FOR THE MID PORTION OF THE WEEK FROM WED THROUGH THU. THIS OCCURS AS THE LONG WAVE TROUGH IS PUSHED EAST OF THE AREA AND WE BECOME UNDER THE INFLUENCE OF SUBSIDENCE DOWNSTREAM OF THE LONG WAVE RIDGE ACROSS THE WRN HALF OF THE CONUS. WE WILL LIKELY REMAIN A LITTLE COOLER THAN AVERAGE WITH THE NW FLOW ALOFT. THE BREAK IN THE RAIN AND QUIET WEATHER LOOKS TO BE SHORT LIVED AS THE NEXT CHC OF PCPN WILL START MAKING ITS WAY TOWARD THE AREA ON FRI. THIS OCCURS AS THE NEXT STRONGER SHORT WAVE RIDING DOWN THE WRN RIDGE WILL APPROACH FROM THE NW. THIS WILL LIKELY NOT HAVE RICH MOISTURE TO WORK WITH AS GULF MOISTURE REMAINS LOCKED UP DOWN SOUTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 741 AM EDT SAT JUN 27 2015 RAIN WILL CONTINUE FOR MOST OF THE DAY OVER TAF SITES NEAR I-69. EXPECT CIGS/VSBY TO BECOME IFR BY 16Z AT ALL OF THOSE TAF SITES. IT WILL BECOME VERY WINDY TOO WITH NORTHEAST WINDS OF 15 TO 25 KNOTS WITH GUSTS TO NEAR 35 KNOTS. RAIN WILL END FROM WEST TO EAST DURING THE LATE AFTERNOON AND EARLY EVENING. LOW CLOUDS MAY PERSIST FOR LAN AND JXN THROUGH THE NIGHT. MEANWHILE FOR MKG... SOLID VFR AND NOT NEARLY AS WINDY. SKIES SHOULD BE MOSTLY CLEAR MOST OF THE DAY THERE ONCE THE CIRRUS SHIELD MOVES OUT BY MID MORNING. GRR WILL BE ON THE EDGE OF RAIN SHIELD TILL AROUND 16Z THEN EXPECT SLOWLY CLEARING SKIES THERE TOO. WINDS WILL BECOME LIGHT AFTER SUNSET FOR BOTH MKG AND GRR. && .MARINE... ISSUED AT 328 AM EDT SAT JUN 27 2015 THE GOOD NEWS IS THE STORM IS JUST FAR ENOUGH TO THE SOUTH AND EAST THAT IT WILL HAVE LITTLE IMPACT ON THE NEAR SHORE WATERS. SO NO HEADLINES SEEM NEEDED AT THIS POINT. && .HYDROLOGY... ISSUED AT 1110 AM EDT SAT JUN 27 2015 RIVER FLOOD ADVISORIES REMAIN IN EFFECT AS RUNOFF OF RAINFALL MAKES ITS WAY THROUGH THE RIVER SYSTEM. RAIN ACCUMULATIONS THROUGH THE NEXT WEEK ARE EXPECTED TO BE A HALF INCH IN MOST AREAS WITH UP TO AN INCH AND A HALF IN THE SOUTH. SIGNIFICANT FLOODING IS NOT EXPECTED... BUT MINOR FLOODING ALONG RIVERS AND IN LOW-LYING AREAS MAY PERSIST THROUGH THE WEEK. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...WDM SHORT TERM...WDM LONG TERM...NJJ AVIATION...WDM HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION
NWS GAYLORD MI
1017 AM EDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1017 AM EDT SAT JUN 27 2015 HIGH CLOUDS REMAIN THE RULE ACROSS LWR MICHIGAN LATE THIS MORNING ALONG THE NW PERIPHERY OF THE PRECIP SHIELD ASSOCIATED WITH LOW PRESSURE TRACKING NE THRU THE OHIO VALLEY. ALL PRECIP REMAINS WELL SOUTH OF OUR CWA...AND SHOULD CONTINUE TO DO SO AS WE HEAD INTO THE AFTERNOON AND EVEN THRU THE EVENING HOURS PER LATEST HRRR AND NAM12. NO CHANGES NEEDED FOR THE AFTERNOON AS SKIES REMAIN MOSTLY CLOUDY IN THE SE HALF OF OUR CWA WHERE HIGH CLOUDS WILL BE RATHER THICK. THE NW HALF OF OUR CWA WILL GENERALLY BE MOSTLY SUNNY WITH THINNER HIGH CLOUDS OVERHEAD. HIGH TEMPS IN THE 70S STILL LOOKS REASONABLE FOR THE AFTERNOON. && .NEAR TERM...(TODAY THROUGH TONIGHT) ISSUED AT 418 AM EDT SAT JUN 27 2015 ...SHOWER OR TWO EASTERN UPPER OTHERWISE MIXED SKIES TODAY... HIGH IMPACT WEATHER POTENTIAL: MINIMAL. PATTERN SYNOPSIS/FORECAST: 03Z SURFACE ANALYSIS SHOWS AN ELONGATED RIDGE AXIS THAT STRETCHES FROM THE CENTRAL HIGH PLAINS EAST ACROSS THE UPPER GREAT LAKES AND INTO SOUTHERN QUEBEC. 1008MB SURFACE LOW OVER SOUTHERN INDIANA ALONG A FRONTAL BOUNDARY THAT EXTENDS BACK INTO FAR SOUTHERN MISSOURI/EASTERN OKLAHOMA...AND A TIGHTENING PRESSURE GRADIENT BETWEEN THESE TWO FEATURES ACROSS ILLINOIS/ INDIANA/OHIO/FAR SOUTHERN LOWER MICHIGAN. DEEP LAYER/WEAK EASTERLY FLOW ACROSS NORTHERN LOWER MICHIGAN WITH A CIRROSTRATUS DECK OVERHEAD...AND NORTHERN EDGE OF A RAIN SHIELD LIFTING NORTH TOWARD THE I-96 CORRIDOR. INDIANA SURFACE LOW EXPECTED TO LIFT NORTHEAST SLOWLY TOWARD LAKE ERIE DURING THE DAY TODAY...WHILE WEAK SURFACE RIDGE AXIS HANGS ON RATHER STUBBORNLY THROUGH TONIGHT. SURFACE LOW OCCLUDES OVERNIGHT AND SLOWS WHILE SECONDARY DEVELOPMENT OCCURS ALONG THE MID ATLANTIC COAST. PRIMARY FORECAST CONCERNS: NORTHERN EXTENT OF RAIN SHIELD ASSOCIATED WITH OHIO VALLEY SYSTEM. POTENTIAL FOR DIURNAL SHOWERS ACROSS UPPER MICHIGAN AND ADJACENT AREAS OF NORTHERN ONTARIO THIS AFTERNOON. TODAY...LOOKS TO BE REAL CLOSE IN TERMS OF HOW FAR NORTHERN EDGE OF PRECIPITATION SHIELD REACHES INTO CENTRAL LOWER MICHIGAN...WITH DOWNWARD BRANCH OF MID LEVEL FRONTOGENESIS MAXIMUM HELPING KEEP PRECIPITATION FROM REACHING TOO FAR INTO THE FORECAST AREA. COULD SEE SOME LIGHT PRECIP SCRAPING PARTS OF GLADWIN/ARENAC/IOSCO COUNTIES. MEANWHILE...AXIS OF WEAK INSTABILITY DEVELOPS WITH HEATING ACROSS UPPER MICHIGAN AND ADJACENT AREAS OF ONTARIO THIS AFTERNOON. COLLIDING LAKE BREEZES EXPECTED AGAIN OVER EASTERN UPPER...WHICH COULD KICK OFF SOME SPOTTY HIGH BASED SHOWERS (MOST HIGH RESOLUTION GUIDANCE SUPPORTS THIS IDEA). OTHERWISE ANOTHER SEASONABLY MILD DAY EXPECTED WITH HIGH TEMPERATURES MAINLY IN THE 70S (COOLER NEAR LAKE HURON IN NORTHEAST LOWER WITH MORE CLOUDS AND ONSHORE WINDS). WINDS WILL BE GUSTIER TODAY THE FARTHER SOUTH (ACTUALLY SOUTHEAST) ONE GOES TODAY (NORTHEAST GUSTS 20-30MPH). TONIGHT...QUIET AGAIN TONIGHT WITH MORE CLOUDS ACROSS NORTHEAST LOWER IN PROXIMITY TO OCCLUDING SURFACE LOW OVER THE LOWER GREAT LAKES. TEMPERATURES MOSTLY NEAR CLIMATOLOGICAL NORMALS (AROUND 50 TO THE MID 50S EXPECTED FOR SUNDAY MORNING LOWS). && .SHORT TERM...(SUNDAY THROUGH MONDAY NIGHT) ISSUED AT 418 AM EDT SAT JUN 27 2015 MODELS ARE COMING INTO AGREEMENT WITH HINTING AT SOME DIURNAL SHOWER POTENTIAL OR EVEN A RUMBLE OF THUNDER OVER THE INLAND AREAS OF NORTHERN LOWER MICHIGAN DURING THE LATE AFTERNOON AND EARLY EVENING HOURS SUNDAY. A THIN RIBBON OF MID-LEVEL MOISTURE ADVECTING IN FROM NORTHERLY WINDS BEHIND THE DEPARTING LOW PRESSURE SYSTEM OVER THE NORTHEASTERN U.S. ALONG WITH CONVERGENCE FROM LAKE BREEZE BOUNDARIES MAY BE JUST ENOUGH TO FIRE SOME OFF. MOST MODELS HAVE 600 TO 800 J/KG OF MUCAPE...JUST NEED THE TRIGGER (SOMETHING NORTHERN MICHIGAN SEEMS TO LACK QUITE A BIT). AS THE PREVIOUS FORECASTER MENTIONED...WILL CONTINUE TO LEAVE THIS SLIGHT CHANCE OF PRECIPITATION OUT UNTIL GREATER CONFIDENCE IS REALIZED AND MAKE SURE CURRENT MODEL TRENDS CONTINUE. BESIDES THE SLIGHT CHANCES OF DIURNAL SHOWERS/THUNDER...SUNDAY WILL BE A NICE SUMMER DAY WITH HIGHS IN THE MID TO UPPER 70S...LIGHT WINDS...AND MOSTLY CLEAR/PARTLY CLOUDY SKIES FOR MOST OF THE DAY. SYNOPTIC MOISTURE FROM THE NEXT WAVE APPROACHING FROM THE WEST WILL BEGIN IMPACTING NORTHERN MICHIGAN WITH INCREASED CLOUDINESS SUNDAY NIGHT THROUGH MONDAY AND THEN PRECIPITATION CHANCES DON/T ENTER THE FORECAST UNTIL THE AFTERNOON HOURS (TRENDING A BIT SLOWER WITH EACH RUN) AND LAST THROUGH THE NIGHT. A RIDGE OF HIGH PRESSURE ALONG WITH A DRIER ATMOSPHERE APPEAR TO HOLD OFF THE ONSET OF PRECIPITATION UNTIL LATER IN THE DAY AS THE UPPER LEVEL TROUGH AND VERY WEAK SURFACE REFLECTION MOVE OVERHEAD...RETURNING SOUTHERLY FLOW AND PWAT VALUES OF BETWEEN 1.00 AND 1.50 INCHES. RAIN WILL BEGIN OVER NORTHWEST LOWER MICHIGAN MONDAY AFTERNOON AND SPREAD EASTWARD INTO THE LATE AFTERNOON/EARLY EVENING HOURS. LOW TEMPERATURES MONDAY MORNING WILL BE IN THE 50S....WHILE HIGH TEMPERATURES MONDAY AFTERNOON WILL BE SLIGHTLY COOLER THAN SUNDAY/S...IN THE LOW TO MID 70S. && .LONG TERM...(TUESDAY THROUGH FRIDAY) ISSUED AT 418 AM EDT SAT JUN 27 2015 POSITIVE PNA CONTINUES A RATHER PROGRESSIVE WEATHER PATTERN OVER THE GREAT LAKES REGION WITH A SERIES OF SHORTWAVE TROUGHS AND WEAK SURFACE LOWS TREKKING THROUGH...BRINGING CHANCES OF PRECIPITATION FOR MUCH OF THE PERIOD...WITH BRIEF PERIODS OF PRECIPITATION-FREE WEATHER IN BETWEEN EACH EVENT. DUE TO THE UNSETTLED WEATHER PATTERN THERE REMAINS MUCH UNCERTAINTY IN TIMING AND EXACT LOCATION OF EACH EVENT. DAYTIME HIGHS SHOULD REMAIN IN THE MID 60S TO MID 70S WITH LOWS IN THE UPPER 40S TO MID 50S THROUGHOUT THE PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 651 AM EDT SAT JUN 27 2015 VFR CONDITIONS ANTICIPATED THROUGH TONIGHT. && .MARINE... ISSUED AT 418 AM EDT SAT JUN 27 2015 TODAY/TONIGHT...NORTHERN EDGE OF A TIGHTER PRESSURE GRADIENT ASSOCIATED WITH A SURFACE LOW MOVING NORTHEAST ACROSS OHIO WILL SPREAD ACROSS SOUTHERN LAKE HURON TODAY...WITH INCREASING NORTHEAST WINDS AS A RESULT FROM THUNDER BAY SOUTH TO SAGINAW BAY. SMALL CRAFT ADVISORIES WILL LIKELY BE NECESSARY IN THESE NEARSHORE AREAS PROBABLY INTO THIS EVENING. MEANWHILE...LIGHTER WINDS EXPECTED FOR THE NEARSHORE ZONES AROUND THE EASTERN U.P. WITH LAKE BREEZES LIKELY. OUTLOOK...NO ADDITIONAL MARINE HAZARDS ANTICIPATED THROUGH SUNDAY NIGHT. && .APX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LH...SMALL CRAFT ADVISORY UNTIL 5 AM EDT SUNDAY FOR LHZ349. LM...NONE. LS...NONE. && $$ UPDATE...MLR NEAR TERM...JPB SHORT TERM...TJL LONG TERM...TJL MARINE...JPB
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
742 AM EDT SAT JUN 27 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 328 AM EDT SAT JUN 27 2015 AN UNSEASONABLY STRONG STORM SYSTEM FOR THIS TIME OF YEAR WILL TRACK ACROSS THE SOUTHERN GREAT LAKES TODAY...HEADING INTO CENTRAL NEW YORK STATE BY SUNDAY MORNING. THIS WILL BRING STRONG WINDS...LOCALLY HEAVY RAIN AND UNSEASONABLY CHILLY TEMPERATURES TO INTERSTATE 69 AREA TODAY. AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HAVE PARTLY CLOUDY SKIES AND HIGHS IN THE 70S. BY TONIGHT THE STORM WILL BE FAR ENOUGH AWAY FROM THIS AREA SO THAT SKIES SHOULD CLEAR FROM WEST TO EAST. SUNDAY SHOULD BE PARTLY SUNNY. ANOTHER STORM SYSTEM WILL BRING SHOWERS AND SCATTERED THUNDERSTORMS INTO THE AREA MONDAY. THOSE MAY LINGER INTO TUESDAY. BEHIND THAT SYSTEM CANADIAN HIGH PRESSURE BUILDS INTO THE AREA FOR MID WEEK. THAT WILL MEAN COOL TEMPERATURES FOR THIS TIME OF YEAR BUT MOSTLY CLEAR SKIES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 A RATHER UNUSUAL STORM FOR THIS TIME OF YEAR WILL TRACK THROUGH THE SOUTHERN GREAT LAKES TODAY AND OVER WESTERN LAKE ERIE TONIGHT. IT WILL BRING STRONG WINDS...CLOSE TO ADVISORY CRITERIA IN THE INTERSTATE 69 AREA WITH RAIN...HEAVY AT TIMES. BUT AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HARDLY KNOW THE STORM IS IN OUR AREA AS SKIES WILL BE PARTLY CLOUDY AND WINDS WILL NOT BE ALL THAT STRONG EITHER. THE GLITCH FOR THIS FORECAST IT TO DECIDE JUST HOW FAR WEST AND NORTH THE RAIN ACTUALLY GETS TODAY. THE GEFS CLIMATE ANOMALIES FOR THIS SYSTEM TELL THE STORY. THE SURFACE PRESSURE OF THE LOW FALLS TO BELOW 1000 MB...THAT IS NEARLY 3.5 STANDARD DEVIATIONS FROM NORMAL OR HAS A RETURN INTERVAL AT THIS TIME OF YEAR OF AROUND ONCE IN TEN YEARS. THIS IS ONE OF THOSE COUPLED JET EVENTS WITH STRONG DYNAMICS AND A LOT OF GULF MOISTURE TO WORK WITH. THE DEFORMATION ZONE OF THE SYSTEM SETS UP OVER OUR SE CWA TODAY BUT THERE IS A CONSIDERABLE AMOUNT OF LOW LEVEL DRY AIR FEEDING INTO THE SYSTEM FROM THE NORTH (BLOCKING HIGH OVER SOUTHERN CANADA). THE MODELS HAVE BE VERY INCONSISTENT WITH JUST HOW FAR WEST THE RAIN GETS. FOR NOW I AM GOING WITH A BLEND OF THE RAP MODEL AND HRRR AND CALLING THAT GOOD. WINDS WILL BE AN ISSUE WITH THIS STORM TOO...THE RAP MODEL IS SHOWING 45 TO 50 KNOTS OVER JACKSON FROM 8 AM THROUGH SUNSET JUST ABOVE THE SURFACE. THE MIXING HEIGHT TAPS INTO THIS SO I WOULD EXPECT SOME GUSTS TO BETWEEN 40 TO 45 KNOTS THIS AFTERNOON IN THAT AREA... JUST UNDER ADVISORY CRITERIA. THIS WILL HAVE TO BE WATCHED. ALL OF THIS MOVES OUT THIS EVENING. THE NEXT SYSTEM MOVES IN SUNDAY NIGHT INTO MONDAY. SINCE THE POLAR JET IS WELL SOUTH OF US BY THEN...THIS WILL BE MORE OF A SHOWERY DAY WITH ISOLATED THUNDERSTORMS IN THE AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 WE CONTINUE TO EXPECT THAT WE WILL BE UNDER THE INFLUENCE OF AN UNSETTLED WEATHER PATTERN FOR THE FIRST FEW PERIODS OF THE LONG TERM PORTION OF THE FCST. THE ANTICIPATED LONG WAVE TROUGH WILL BE OVER THE AREA FROM MON NIGHT INTO TUE NIGHT. THE BEST CHC OF RAIN WILL BEST MON NIGHT WITH A FAIRLY STOUT CLOSED SHORT WAVE AND ASSOCIATED SFC LOW PASSING THROUGH. RAIN WILL REMAIN POSSIBLE TUE AND TUE NIGHT...BUT IT DOES NOT LOOK TO BE AS WIDESPREAD WITH A WEAKER WAVE MOVING THROUGH. IT WILL ALSO BE MORE DIURNALLY FOCUSED AND AWAY FROM THE LAKE. THE TREND OVER THE PAST COUPLE OF DAYS HAS DEFINITELY BEEN FOR A DRIER PERIOD FOR THE MID PORTION OF THE WEEK FROM WED THROUGH THU. THIS OCCURS AS THE LONG WAVE TROUGH IS PUSHED EAST OF THE AREA AND WE BECOME UNDER THE INFLUENCE OF SUBSIDENCE DOWNSTREAM OF THE LONG WAVE RIDGE ACROSS THE WRN HALF OF THE CONUS. WE WILL LIKELY REMAIN A LITTLE COOLER THAN AVERAGE WITH THE NW FLOW ALOFT. THE BREAK IN THE RAIN AND QUIET WEATHER LOOKS TO BE SHORT LIVED AS THE NEXT CHC OF PCPN WILL START MAKING ITS WAY TOWARD THE AREA ON FRI. THIS OCCURS AS THE NEXT STRONGER SHORT WAVE RIDING DOWN THE WRN RIDGE WILL APPROACH FROM THE NW. THIS WILL LIKELY NOT HAVE RICH MOISTURE TO WORK WITH AS GULF MOISTURE REMAINS LOCKED UP DOWN SOUTH. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 741 AM EDT SAT JUN 27 2015 RAIN WILL CONTINUE FOR MOST OF THE DAY OVER TAF SITES NEAR I-69. EXPECT CIGS/VSBY TO BECOME IFR BY 16Z AT ALL OF THOSE TAF SITES. IT WILL BECOME VERY WINDY TOO WITH NORTHEAST WINDS OF 15 TO 25 KNOTS WITH GUSTS TO NEAR 35 KNOTS. RAIN WILL END FROM WEST TO EAST DURING THE LATE AFTERNOON AND EARLY EVENING. LOW CLOUDS MAY PERSIST FOR LAN AND JXN THROUGH THE NIGHT. MEANWHILE FOR MKG... SOLID VFR AND NOT NEARLY AS WINDY. SKIES SHOULD BE MOSTLY CLEAR MOST OF THE DAY THERE ONCE THE CIRRUS SHIELD MOVES OUT BY MID MORNING. GRR WILL BE ON THE EDGE OF RAIN SHIELD TILL AROUND 16Z THEN EXPECT SLOWLY CLEARING SKIES THERE TOO. WINDS WILL BECOME LIGHT AFTER SUNSET FOR BOTH MKG AND GRR. && .MARINE... ISSUED AT 328 AM EDT SAT JUN 27 2015 THE GOOD NEWS IS THE STORM IS JUST FAR ENOUGH TO THE SOUTH AND EAST THAT IT WILL HAVE LITTLE IMPACT ON THE NEAR SHORE WATERS. SO NO HEADLINES SEEM NEEDED AT THIS POINT. && .HYDROLOGY... ISSUED AT 134 PM EDT FRI JUN 26 2015 RIVER FLOOD ADVISORIES REMAIN IN EFFECT AS RUNOFF MAKES ITS WAY THROUGH THE RIVER SYSTEM. OFF AND ON RAIN CHANCES ARE POSSIBLE THROUGH THE WEEKEND. LIGHT ACCUMULATIONS CAN BE EXPECTED THROUGH SATURDAY NIGHT... MAINLY AN ADDITIONAL 0.10 TO 0.25 INCHES. MORE LIGHT RAIN IS POSSIBLE EARLY NEXT WEEK. SIGNIFICANT FLOODING IS NOT EXPECTED. MINOR FLOODING ALONG RIVERS AND IN LOW-LYING AREAS MAY PERSIST THROUGH THE WEEKEND. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...WDM SHORT TERM...WDM LONG TERM...NJJ AVIATION...WDM HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION...CORRECTED
NWS GRAND RAPIDS MI
328 AM EDT SAT JUN 27 2015 LATEST UPDATE... SYNOPSIS/SHORT TERM/LONG TERM/MARINE .SYNOPSIS... ISSUED AT 328 AM EDT SAT JUN 27 2015 AN UNSEASONABLY STRONG STORM SYSTEM FOR THIS TIME OF YEAR WILL TRACK ACROSS THE SOUTHERN GREAT LAKES TODAY...HEADING INTO CENTRAL NEW YORK STATE BY SUNDAY MORNING. THIS WILL BRING STRONG WINDS...LOCALLY HEAVY RAIN AND UNSEASONABLY CHILLY TEMPERATURES TO INTERSTATE 69 AREA TODAY. AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HAVE PARTLY CLOUDY SKIES AND HIGHS IN THE 70S. BY TONIGHT THE STORM WILL BE FAR ENOUGH AWAY FROM THIS AREA SO THAT SKIES SHOULD CLEAR FROM WEST TO EAST. SUNDAY SHOULD BE PARTLY SUNNY. ANOTHER STORM SYSTEM WILL BRING SHOWERS AND SCATTERED THUNDERSTORMS INTO THE AREA MONDAY. THOSE MAY LINGER INTO TUESDAY. BEHIND THAT SYSTEM CANADIAN HIGH PRESSURE BUILDS INTO THE AREA FOR MID WEEK. THAT WILL MEAN COOL TEMPERATURES FOR THIS TIME OF YEAR BUT MOSTLY CLEAR SKIES. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 A RATHER UNUSUAL STORM FOR THIS TIME OF YEAR WILL TRACK THROUGH THE SOUTHERN GREAT LAKES TODAY AND OVER WESTERN LAKE ERIE TONIGHT. IT WILL BRING STRONG WINDS...CLOSE TO ADVISORY CRITERIA IN THE INTERSTATE 69 AREA WITH RAIN...HEAVY AT TIMES. BUT AREAS NORTH AND WEST OF A LINE FROM HOLLAND TO ALMA WILL HARDLY KNOW THE STORM IS IN OUR AREA AS SKIES WILL BE PARTLY CLOUDY AND WINDS WILL NOT BE ALL THAT STRONG EITHER. THE GLITCH FOR THIS FORECAST IT TO DECIDE JUST HOW FAR WEST AND NORTH THE RAIN ACTUALLY GETS TODAY. THE GEFS CLIMATE ANOMALIES FOR THIS SYSTEM TELL THE STORY. THE SURFACE PRESSURE OF THE LOW FALLS TO BELOW 1000 MB...THAT IS NEARLY 3.5 STANDARD DEVIATIONS FROM NORMAL OR HAS A RETURN INTERVAL AT THIS TIME OF YEAR OF AROUND ONCE IN TEN YEARS. THIS IS ONE OF THOSE COUPLED JET EVENTS WITH STRONG DYNAMICS AND A LOT OF GULF MOISTURE TO WORK WITH. THE DEFORMATION ZONE OF THE SYSTEM SETS UP OVER OUR SE CWA TODAY BUT THERE IS A CONSIDERABLE AMOUNT OF LOW LEVEL DRY AIR FEEDING INTO THE SYSTEM FROM THE NORTH (BLOCKING HIGH OVER SOUTHERN CANADA). THE MODELS HAVE BE VERY INCONSISTENT WITH JUST HOW FAR WEST THE RAIN GETS. FOR NOW I AM GOING WITH A BLEND OF THE RAP MODEL AND HRRR AND CALLING THAT GOOD. WINDS WILL BE AN ISSUE WITH THIS STORM TOO...THE RAP MODEL IS SHOWING 45 TO 50 KNOTS OVER JACKSON FROM 8 AM THROUGH SUNSET JUST ABOVE THE SURFACE. THE MIXING HEIGHT TAPS INTO THIS SO I WOULD EXPECT SOME GUSTS TO BETWEEN 40 TO 45 KNOTS THIS AFTERNOON IN THAT AREA... JUST UNDER ADVISORY CRITERIA. THIS WILL HAVE TO BE WATCHED. ALL OF THIS MOVES OUT THIS EVENING. THE NEXT SYSTEM MOVES IN SUNDAY NIGHT INTO MONDAY. SINCE THE POLAR JET IS WELL SOUTH OF US BY THEN...THIS WILL BE MORE OF A SHOWERY DAY WITH ISOLATED THUNDERSTORMS IN THE AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 AM EDT SAT JUN 27 2015 WE CONTINUE TO EXPECT THAT WE WILL BE UNDER THE INFLUENCE OF AN UNSETTLED WEATHER PATTERN FOR THE FIRST FEW PERIODS OF THE LONG TERM PORTION OF THE FCST. THE ANTICIPATED LONG WAVE TROUGH WILL BE OVER THE AREA FROM MON NIGHT INTO TUE NIGHT. THE BEST CHC OF RAIN WILL BEST MON NIGHT WITH A FAIRLY STOUT CLOSED SHORT WAVE AND ASSOCIATED SFC LOW PASSING THROUGH. RAIN WILL REMAIN POSSIBLE TUE AND TUE NIGHT...BUT IT DOES NOT LOOK TO BE AS WIDESPREAD WITH A WEAKER WAVE MOVING THROUGH. IT WILL ALSO BE MORE DIURNALLY FOCUSED AND AWAY FROM THE LAKE. THE TREND OVER THE PAST COUPLE OF DAYS HAS DEFINITELY BEEN FOR A DRIER PERIOD FOR THE MID PORTION OF THE WEEK FROM WED THROUGH THU. THIS OCCURS AS THE LONG WAVE TROUGH IS PUSHED EAST OF THE AREA AND WE BECOME UNDER THE INFLUENCE OF SUBSIDENCE DOWNSTREAM OF THE LONG WAVE RIDGE ACROSS THE WRN HALF OF THE CONUS. WE WILL LIKELY REMAIN A LITTLE COOLER THAN AVERAGE WITH THE NW FLOW ALOFT. THE BREAK IN THE RAIN AND QUIET WEATHER LOOKS TO BE SHORT LIVED AS THE NEXT CHC OF PCPN WILL START MAKING ITS WAY TOWARD THE AREA ON FRI. THIS OCCURS AS THE NEXT STRONGER SHORT WAVE RIDING DOWN THE WRN RIDGE WILL APPROACH FROM THE NW. THIS WILL LIKELY NOT HAVE RICH MOISTURE TO WORK WITH AS GULF MOISTURE REMAINS LOCKED UP DOWN SOUTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 149 AM EDT SAT JUN 27 2015 OUR MAIN FOCUS WITH THE 06Z FCSTS IS THE RAIN AND POTENTIALLY LOWER CONDITIONS SOUTH OF THE AREA THAT WILL MOVE IN ACROSS SOME OF THE TERMINALS THIS MORNING. LIGHT RAIN IS ALREADY MOVING INTO THE I-94 TERMINALS...AND IS ABOUT TO MOVE INTO KLAN. SO FAR THIS HAS BEEN LIGHT RAIN OUT OF A 10K FT CIG. WE EXPECT THIS TO CONTINUE FOR THE NEXT FEW HOURS. SOME LOWER CIGS WILL MOVE IN DOWN SOUTH TOWARD DAYBREAK FOR A BIT AS THE SFC LOW APPROACHES. SOME MVFR IS LIKELY AT THAT TIME. WE ARE THINKING THAT THE RAIN WILL GRADUALLY SLIDE EAST THIS AFTERNOON AS THE LOW STARTS TO MOVE EAST OF THE AREA. WIDESPREAD RAIN SHOULD MOVE OUT WITH SOME SPOTTY SHOWERS REMAINING POSSIBLE LATE AFTERNOON TOWARD KJXN. WINDS WILL PICK UP OUT OF THE N/NE AFTER SUNRISE THIS MORNING. GUSTS IN THE 20-30 KNOT RANGE ARE LIKELY...ESPECIALLY FURTHER EAST. SOME HIGHER GUSTS WILL BE POSSIBLE. CLOUDS WILL CLEAR OUT THROUGH THIS EVENING FROM WEST TO EAST...AND WINDS WILL DECOUPLE. && .MARINE... ISSUED AT 328 AM EDT SAT JUN 27 2015 THE GOOD NEWS IS THE STORM IS JUST FAR ENOUGH TO THE SOUTH AND EAST THAT IT WILL HAVE LITTLE IMPACT ON THE NEAR SHORE WATERS. SO NO HEADLINES SEEM NEEDED AT THIS POINT. && .HYDROLOGY... ISSUED AT 134 PM EDT FRI JUN 26 2015 RIVER FLOOD ADVISORIES REMAIN IN EFFECT AS RUNOFF MAKES ITS WAY THROUGH THE RIVER SYSTEM. OFF AND ON RAIN CHANCES ARE POSSIBLE THROUGH THE WEEKEND. LIGHT ACCUMULATIONS CAN BE EXPECTED THROUGH SATURDAY NIGHT... MAINLY AN ADDITIONAL 0.10 TO 0.25 INCHES. MORE LIGHT RAIN IS POSSIBLE EARLY NEXT WEEK. SIGNIFICANT FLOODING IS NOT EXPECTED. MINOR FLOODING ALONG RIVERS AND IN LOW-LYING AREAS MAY PERSIST THROUGH THE WEEKEND. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...NONE. && $$ SYNOPSIS...WDM SHORT TERM...WDM LONG TERM...NJJ AVIATION...NJJ HYDROLOGY...63 MARINE...WDM
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
1015 AM CDT SAT JUN 27 2015 .UPDATE... AN UNSEASONABLY SIGNIFICANT UPPER TROUGH IS DROPPING DOWN INTO THE LOWER MS VALLEY CURRENTLY...DRAGGING A COLD FRONT SLOWLY TOWARD THE ARKLAMISS DELTA. OBSERVATIONS THIS MORNING DEPICT HIGH MOISTURE LEVELS (1.75 TO 2 INCH PW VALUES) POOLED AHEAD OF THIS FRONT...WHICH IS HELPING FUEL SCATTERED SHOWERS AND EMBEDDED THUNDERSTORMS ACROSS MUCH OF THE FORECAST AREA. THE OVERALL SYNOPTIC SITUATION SUGGESTS A FEW DIFFERENT SOURCES OF ATMOSPHERIC LIFT TODAY IN ASSOCIATION WITH THE INCOMING TROUGH...BUT THESE SOURCES ARE NOT REALLY IN PHASE. THE LATTER FACT WILL MAKES IT DIFFICULT TO PREDICT WITH FINE DETAIL HIGHEST RAIN CHANCES...ALTHOUGH CONFIDENCE IS STILL HIGH MOST LOCATIONS IN THE REGION WILL AT LEAST SEE A SHOWER BEFORE THE DAY IS OUT. MAIN ALTERATIONS FROM PREVIOUS WERE TO RAISE POPS A BIT IN EAST-CENTRAL MS (AND HIGH TEMPS CONVERSELY LOWERED A BIT THERE) DUE TO HRRR INSISTENCE OF HIGHEST CONCENTRATION OF CONVECTION THROUGH EARLY TO MID AFTERNOON. BY LATE THIS AFTERNOON INTO EARLY THIS EVENING SHOWERS SHOULD BE DIMINISHING AND CONFINED MAINLY TO SOUTHERN ZONES AS THE COLD FRONT ITSELF SINKS INTO THE HEART OF THE CWA. SIMILAR TO THE PREVIOUS SHIFT...NOTHING IN OUR MORNING SOUNDING ANALYSIS POINTS TO MENTIONING SEVERE POTENTIAL WITH STORMS IN THE HWO. CONSIDERING THERE WILL BE A BIT OF SHEAR AND INSTABILITY JUXTAPOSED IN SOUTHERN ZONES THROUGH MID AFTERNOON WE WILL BE WATCHING THOSE AREAS FOR AT LEAST A FEW STRONG STORMS BUT POTENTIAL FOR ANY TRULY SEVERE STORMS WILL BE LIMITED A GREAT DEAL BY THE POOR LAPSE RATE ENVIRONMENT. /BB/ && .AVIATION...THE COMBINATION OF SCATTERED CONVECTION AND VARIABLE CEILING HEIGHTS AS A COLD FRONT PUSHES SOUTHEAST THROUGH THE AREA TODAY...WILL RESULT IN A MIX OF MAINLY MVFR/VFR FLIGHT CATEGORIES AT TAF SITES ACROSS THE REGION FROM NOW THROUGH MUCH OF THE AFTERNOON HOURS. CONVECTION WILL BE CAPABLE OF PRODUCING GUSTY WINDS BETWEEN 17-26 KNOTS...FREQUENT LIGHTNING STRIKES...AND BRIEF BUT HEAVY DOWNPOURS. WINDS AHEAD OF THE FRONT WILL BE FROM SOUTHWEST TO WEST BETWEEN 5-10 KNOTS...BUT BEHIND THE FRONT WILL BECOME NORTHWESTERLY BETWEEN 5-8 KNOTS. WINDS WILL GRADUALLY SUBSIDE TO AROUND 3 KNOTS OVERNIGHT...WITH VFR CONDITIONS FORECAST TO PREVAIL AT ALL SITES HEADING INTO SUNDAY MORNING. /19/ && .PREV DISCUSSION... /ISSUED 422 AM CDT SAT JUN 27 2015/ DISCUSSION... SHORT TERM (TODAY THROUGH SUNDAY NIGHT)...A COLD FRONT IS NOW PUSHING SOUTHWARD ACROSS THE MIDSOUTH REGION AND WILL ENTER THE FORECAST AREA LATER THIS MORNING. CONVECTION HAS BEEN ONGOING OVERNIGHT ALONG A PREFRONTAL TROUGH FROM THE ARKLATEX EASTWARD INTO THE ARKLAMISS DELTA. THOUGH NONE OF THE STORMS HAVE BEEN SEVERE, THERE HAVE BEEN A FEW PROLIFIC LIGHTNING PRODUCERS AND TRAINING OF HEAVIER CONVECTION WHICH NECESSITATED A FLASH FLOOD WARNING. I`M EXPECTING THIS ACTIVITY TO GRADUALLY LOSE STEAM OVER THE NEXT SEVERAL HOURS AS WE CROSS THROUGH THE NOCTURNAL INSTABILITY MINIMUM. HOWEVER, THE RESULTANT OUTFLOW BOUNDARIES SHOULD HELP INITIATE NEW CONVECTION FARTHER SOUTH DURING THE HEATING OF THE DAY. AS THE FRONT CONTINUES SOUTHWARD THROUGH THE DAY, THE BEST CHANCE OF NEW DEVELOPMENT THIS AFTERNOON AND EARLY EVENING WILL BE ALONG AND SOUTH OF I-20. WHILE SOME STRONG STORMS CANNOT BE RULED OUT AS UPPER FORCING INCREASES AND DEEP LAYER SHEAR APPROACHES 30 KTS, LAPSE RATES ARE EXPECTED TO BE RATHER UNIMPRESSIVE WHICH SHOULD HELP LIMIT MORE ROBUST CONVECTION. THE FRONT WILL CLEAR THE SOUTHERN PART OF THE AREA TONIGHT WITH PERHAPS A FEW SHOWERS LINGERING INTO THE NIGHT ALONG THE 98 CORRIDOR. A SUBSTANTIALLY DRIER AIRMASS WILL BUILD IN, WITH PWATS DROPPING TO BELOW AN INCH IN MOST AREAS. THIS WILL MAKE FOR A MUCH MORE COMFORTABLE SUNDAY ACROSS THE REGION, EVEN AS TEMPS RISE TO NEAR 90 DURING THE DAY. DEWPOINTS WILL MIX OUT INTO THE LOW/MID 60S AND POSSIBLY EVEN UPPER 50S. LOW TEMPS WILL PREDOMINATELY BE IN THE 60S TONIGHT AND ESPECIALLY SUNDAY NIGHT. /DL/ LONG TERM (MONDAY THROUGH NEXT SATURDAY)...COME MONDAY AN AMPLIFIED PATTERN OF RIDGING OVER THE WESTERN CONUS AND TROUGHING OVER THE EASTERN CONUS WILL BE IN PLACE. OUR CWA WILL SEE NORTHWEST FLOW ALOFT WITH A POTENT SHORTWAVE TROUGH PROGGED TO BE DROPPING OVER THE MID MISSISSIPPI VALLEY AT DAYBREAK. THE BULK OF THE ENERGY WITH THE SHORTWAVE WILL TRACK WELL NORTH OF OUR CWA DURING THE DAY BUT THE SHORTWAVE WILL HELP SEND A WEAK SURFACE BOUNDARY INTO OUR NORTHERN ZONES BY TUESDAY MORNING. PWATS WILL START OUT AROUND ONE INCH FOR MOST OF OUR CWA MONDAY MORNING BUT INCREASE TO AN INCH AND A HALF BY MONDAY EVENING TO FUEL ISOLATED CONVECTION ACROSS THE NORTH AND OVER OUR SOUTH. THE ACTIVITY IN THE NORTH WILL BE DUE IN PART TO THE APPROACHING SURFACE BOUNDARY AND ACTIVITY IN THE SOUTH WILL BE DUE IN PART TO THE SEA BREEZE. GREATER COVERAGE OF STORMS AREAWIDE IS EXPECTED TUESDAY AS THE SHORTWAVE TROUGH AXIS AND WEAK SURFACE BOUNDARY MOVE OVER THE AREA. A MOIST AIRMASS WILL BE BACK OVER THE CWA WITH SURFACE DEW POINTS IN THE LOWER 70S AND PWATS AROUND AN INCH AND THREE QUARTERS. WEDNESDAY INTO THE THURSDAY THE AMPLIFIED UPPER LEVEL PATTERN WILL BREAK DOWN. THERE ARE TIMING DIFFERENCES IN THE MODELS BUT ANOTHER SHORTWAVE IS EXPECTED TO SWING ACROSS OUR REGION LATE WEDNESDAY INTO THURSDAY. THIS SHORTWAVE LOOKS TO HELP SUPPORT ANOTHER SURFACE BOUNDARY DROPPING INTO THE NORTHERN PORTIONS OF OUR CWA. MODEL CONSENSUS SUGGESTS THIS BOUNDARY WILL STALL ACROSS OUR NORTH THURSDAY AND MOVE BACK NORTH OF OUR CWA FRIDAY. GREATEST RAIN CHANCES THURSDAY THROUGH FRIDAY IS EXPECTED IN OUR NORTH. NORMAL LOWS RUN 69-71F AND NORMAL HIGHS RUN 91-92F. TEMPERATURES WILL BE NEAR NORMAL MOST OF NEXT WEEK WITH SLIGHTLY WARMER THAN NORMAL BY FRIDAY. WARMER AND DRIER CONDITIONS ARE EXPECTED SATURDAY AS HIGH PRESSURE STRENGTHENS OVER OUR CWA. /22/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 86 68 89 68 / 66 25 6 1 MERIDIAN 84 68 88 63 / 75 28 7 0 VICKSBURG 87 67 89 66 / 59 20 6 1 HATTIESBURG 89 72 91 68 / 70 48 18 10 NATCHEZ 87 69 86 69 / 69 39 10 10 GREENVILLE 86 66 89 66 / 46 9 0 0 GREENWOOD 84 65 87 65 / 53 11 0 0 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/19/DL/22/
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1247 PM CDT Sat Jun 27 2015 .SHORT TERM: (Through Late Tonight) Issued at 310 AM CDT Sat Jun 27 2015 Have added slight chance for thunderstorms this afternoon based on that there was upstream convection today, and forecast soundings show that atmosphere will become unstable again today. Both the NAM and GFS show a upper shortwave trough moving across the area during the midday hours with the GFS developing some QPF over the area during the afternoon. Even the HRRR supports this idea with it breaking out isolated convection during the afternoon over most of the CWA. This convection will die out quickly this evening with the loss of daytime heating. Temperatures today will remain below normal even with mixing up to 850mb. .LONG TERM: (Sunday through Friday) Issued at 310 AM CDT Sat Jun 27 2015 (Sunday and Monday) A second, stronger trough will drop down in northwest upper flow on Sunday night. There will be additional thunderstorms develop ahead of it on Sunday as the atmosphere becomes unstable with MLCAPES in the 1000-2000 J/kg range. A few isolated severe thunderstorms should be possible over the area Sunday into Sunday evening and deep layer shear of around 40kts. The trough will move off to the southeast by Monday, though the atmosphere will still be unstable behind the front today. Will keep a slight chance of showers and thunderstorms over part of the forecast area on Monday. Temperatures these two days look slightly warmer as mixing will be up into the 800-850mb range. (Tuesday through Friday) Upper pattern will remain amplified during this period with large upper high in the western CONUS and mean trough in the east. This will keep a meandering frontal boundary close to our area during mid-late week. Temperatures will remain below normal. Britt && .AVIATION: (For the 18z TAFs through 18z Sunday Afternoon) Issued at 1213 PM CDT Sat Jun 27 2015 Nly flow will continue for terminals this afternoon. CU field is expected to continue to develop with much of the area becoming BKN this afternoon. Isod to widely sct SHRA are expected to develop this afternoon, but have not put in TAF attm due to low chance of impacting a terminal. Otherwise, cu will dissipate this evening leaving much of tonight clear. FG development is possible with light and vrb winds. Winds will become swly Sun morning ahead of an approaching system. Precip may reach UIN shortly before 18z Sun, but have kept out of TAF attm due to low confidence in timing. Specifics for KSTL: Nly winds will persist this afternoon with cu field expected to become BKN for much of this afternoon. Isod to widely sct SHRA are expected to develop this afternoon. CU expected to dissipate early this eve leaving overnight clear. Winds will become swly Sun morning ahead of an approaching system. Precip may reach terminal before 00z Mon, but have kept out of TAF for now. Tilly && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
658 AM CDT Sat Jun 27 2015 .SHORT TERM: (Through Late Tonight) Issued at 310 AM CDT Sat Jun 27 2015 Have added slight chance for thunderstorms this afternoon based on that there was upstream convection today, and forecast soundings show that atmosphere will become unstable again today. Both the NAM and GFS show a upper shortwave trough moving across the area during the midday hours with the GFS developing some QPF over the area during the afternoon. Even the HRRR supports this idea with it breaking out isolated convection during the afternoon over most of the CWA. This convection will die out quickly this evening with the loss of daytime heating. Temperatures today will remain below normal even with mixing up to 850mb. .LONG TERM: (Sunday through Friday) Issued at 310 AM CDT Sat Jun 27 2015 (Sunday and Monday) A second, stronger trough will drop down in northwest upper flow on Sunday night. There will be additional thunderstorms develop ahead of it on Sunday as the atmosphere becomes unstable with MLCAPES in the 1000-2000 J/kg range. A few isolated severe thunderstorms should be possible over the area Sunday into Sunday evening and deep layer shear of around 40kts. The trough will move off to the southeast by Monday, though the atmosphere will still be unstable behind the front today. Will keep a slight chance of showers and thunderstorms over part of the forecast area on Monday. Temperatures these two days look slightly warmer as mixing will be up into the 800-850mb range. (Tuesday through Friday) Upper pattern will remain amplified during this period with large upper high in the western CONUS and mean trough in the east. This will keep a meandering frontal boundary close to our area during mid-late week. Temperatures will remain below normal. Britt && .AVIATION: (For the 12z TAFs through 12z Sunday Morning) Issued at 638 AM CDT Sat Jun 27 2015 Fog will dissipate in UIN later this morning, while the MVFR stratus deck in COU and the St Louis metro area advects south of this area. There will be scattered to broken diurnal cumulus clouds developing across the area late this morning and afternoon with isolated afternoon showers/storms possible. The diurnal cumulus clouds will dissipate early this evening. The northerly surface winds will become light early this evening as the surface low over western OH moves further east and the surface ridge over the Plains moves southeastward through our area. Specifics for KSTL: The MVFR stratus cloud deck will advect south of STL later this morning. Scattered to broken diurnal cumulus clouds will develop late this morning and afternoon. There may be isolated showers and storms this afternoon, but will leave out of the STL TAF for now due to sparse coverage expected. The cumulus clouds should dissipate early this evening due to the loss of daytime heating. The northerly surface wind will become light early this evening, then become southwesterly by late Sunday morning as the surface ridge shifts southeast of STL and a cold front approaches. GKS && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS ST LOUIS MO
311 AM CDT Sat Jun 27 2015 .SHORT TERM: (Through Late Tonight) Issued at 310 AM CDT Sat Jun 27 2015 Have added slight chance for thunderstorms this afternoon based on that there was upstream convection today, and forecast soundings show that atmosphere will become unstable again today. Both the NAM and GFS show a upper shortwave trough moving across the area during the midday hours with the GFS developing some QPF over the area during the afternoon. Even the HRRR supports this idea with it breaking out isolated convection during the afternoon over most of the CWA. This convection will die out quickly this evening with the loss of daytime heating. Temperatures today will remain below normal even with mixing up to 850mb. .LONG TERM: (Sunday through Friday) Issued at 310 AM CDT Sat Jun 27 2015 (Sunday and Monday) A second, stronger trough will drop down in northwest upper flow on Sunday night. There will be additional thunderstorms develop ahead of it on Sunday as the atmosphere becomes unstable with MLCAPES in the 1000-2000 J/kg range. A few isolated severe thunderstorms should be possible over the area Sunday into Sunday evening and deep layer shear of around 40kts. The trough will move off to the southeast by Monday, though the atmosphere will still be unstable behind the front today. Will keep a slight chance of showers and thunderstorms over part of the forecast area on Monday. Temperatures these two days look slightly warmer as mixing will be up into the 800-850mb range. (Tuesday through Friday) Upper pattern will remain amplified during this period with large upper high in the western CONUS and mean trough in the east. This will keep a meandering frontal boundary close to our area during mid-late week. Temperatures will remain below normal. Britt && .AVIATION: (For the 06z TAFs through 06z Saturday Night) Issued at 1128 PM CDT Fri Jun 26 2015 Lingering light SHRAs continue to dsspt this evng. Main concern for the overnight into Friday mrng will be the height and coverage of stratus. Obs indicate it will start out around 1.5 kft with pockets of high end IFR. KUIN and KCOU appear to be on the edge at this point though with the low level wind advecting the stratus in from IL...KUIN will likely be impacted before KCOU. Stratus should begin to break up and transition to cu drng the late mrng/early aftn and dsspt after 00Z. Winds will remain nthrly thru the day becmng lght/vrb overnight as the sfc ridge axis passes. Specifics for KSTL: MVFR stratus should continue to advect in from IL overnight and then transition to cu thru the day. Winds will remain nthrly thru the day and then become lght/vrb sat night as the sfc ridge axis passes. Miller && .LSX WATCHES/WARNINGS/ADVISORIES: MO...NONE. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
840 PM MDT SUN JUN 28 2015 .UPDATE... VERY LITTLE IN THE WAY OF CHANGE WAS MADE TO THE FORECAST. WE DID GO WITH A DRY FORECAST EVERYWHERE THROUGH 06 UTC AS SLOW BOUNDARY LAYER COOLING IS QUICKLY CAUSING CONVECTION TO DIMINISH. A LOW-END CHANCE OF A SHOWER OR THUNDERSTORM WAS MAINTAINED IN THE FORECAST IN THE BAKER AND EKALAKA AREAS AFTER MIDNIGHT AS A WEAK SHORTWAVE TROUGH CROSSES THE AREA. HOWEVER...CELLS WHICH FORMED IN PART DUE TO THAT WAVE IN NORTHEASTERN MT EARLIER THIS EVENING DIED AS THEY MOVED SOUTHEAST...AND RECENT HRRR SIMULATIONS HAVE BEEN TRENDING AWAY FROM CONVECTION IN SOUTHEASTERN MT OVERNIGHT...SO CONFIDENCE IN ANYTHING OCCURRING IS LOW. SCHULTZ && .SHORT TERM...VALID FOR MON AND TUE... STRONG UPPER RIDGE REMAINS ANCHORED OVER THE INTERMOUNTAIN WEST BRINGING INTENSE HEAT TO THE ENTIRE REGION. AREA OF PV EMBEDDED WITHIN THE NW FLOW ALOFT HAS ALLOWED FOR SOME SHOWERS AND WEAK THUNDERSTORMS TO DEVELOP OFF THE CRAZIES/BELTS/SNOWIES AND DRIFT TO THE SOUTHEAST...MAKING IT A LITTLE OFF THE TERRAIN. NOT MUCH GOING ON FURTHER EAST AT THIS TIME BUT AM CURIOUS TO SEE IF SHORTWAVE APPROACHING EASTERN MT IS ENOUGH TO GET SOME CONVECTION GOING ACROSS OUR EASTERN ZONES WHERE MOISTURE IS GREATER AND THERE IS SOME LOW LEVEL MOISTURE CONVERGENCE. NOT SURE HOW IT WILL PAN OUT BUT HAVE ADDED A LOW POP FOR ISOLD TS IN OUR EAST BEGINNING AT 00Z. HOTTEST DAY OF THE CURRENT HOT SPELL LOOKS TO BE TOMORROW AS RIDGE AXIS BEGINS TO SHIFT EAST IN RESPONSE TO SHORTWAVE MOVING THRU THE PAC NW. WARMEST 700MB TEMPS OF +18C WILL BE IN SOUTH CENTRAL MT... AND WE WILL HAVE AN EASTERLY SFC WIND...BUT MIXING OF THIS AIRMASS SHOULD SUPPORT TEMPS IN THE UPPER 90S OR NEAR 100F EVERYWHERE EXCEPT NEAR THE DAKOTAS BORDER. THIS WOULD OBVIOUSLY BE THE HOTTEST DAY WE HAVE HAD YET IN 2015...AND A SOMEWHAT EARLY TIME OF THE SEASON TO BE TALKING ABOUT TRIPLE DIGITS. MONSOONAL PLUME OVER THE WESTERN CONUS WILL SPILL INTO OUR WEST BY LATE AFTN/EVNG ALLOWING FOR PWATS TO RISE TO NEAR AN INCH AND RESULTING IN INCREASED THUNDERSTORM POTENTIAL ESPECIALLY FOR AREAS WEST OF BILLINGS. THIS HIGH-BASED ACTIVITY HAS THE POTENTIAL TO PRODUCE GUSTY WINDS. POSSIBILITY OF STORMS WILL CONTINUE THROUGH TUESDAY AS SHORTWAVE FINALLY PASSES THROUGH...WITH DRIER AIR AND SUBSIDENCE IN ITS WAKE...SO SHOULD SEE ANY SHOWER/TSTM ACTIVITY TAPER OFF IN THE AFTERNOON. TUESDAY WILL BE POST-FRONTAL BUT JUST SLIGHTLY COOLER THAN MONDAY PER THE MIXED NW WINDS AND STILL VERY HIGH HEIGHTS. HAVE TWEAKED EXPECTED HIGHS UP JUST A BIT TO THE MID OR EVEN UPPER 90S. BREEZY AND DRY POST FRONTAL CONDITIONS ON TUESDAY WILL BE A FIRE WEATHER CONCERN WHERE FUELS ARE SUFFICIENTLY DRY. SOMETHING TO THINK ABOUT...ESPECIALLY IF WE SEE SOME LIGHTNING MONDAY NIGHT INTO TUESDAY. JKL .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... FLATTENING RIDGE WILL TURN TO NORTHWESTERLY FLOW BY MID WEEK. THICKNESS VALUES WILL STILL BE QUITE HIGH...BUT NOTHING LIKE WHAT WAS SEEN EARLIER THIS WEEK. HIGHS WILL REMAIN IN THE MID TO UPPER 80S ACROSS THE CWA. A FEW SHORT WAVES WILL SKIRT ACROSS THE FAR PORTIONS OF NORTHEASTERN MONTANA THURSDAY INTO FRIDAY...BUT PRECIP CHANCES FOR BYZ CWA LOOK MINIMAL. ANOTHER VORT MAX WILL WORK ITS WAY ACROSS THE NORTHERN ROCKIES NEXT SATURDAY AND DRAG WITH IT A COLD FRONT BY EARLY SUNDAY. MODEL PW VALUES FOR THE CENTRAL AND EASTERN ZONES ARE ABOVE AN INCH. UNFORTUNATELY...THIS MAY BE THE BEST CHANCE FOR ANY MEASURABLE PRECIPITATION IN THE EXTENDED PERIOD. SINGER && .AVIATION... VFR CONDITIONS AND LIGHT WINDS WILL PREVAIL TONIGHT AND MONDAY. A SMALL CHANCE OF A THUNDERSTORM WITH SUB-VFR CONDITIONS DOES EXIST IN FAR SOUTHEASTERN MT AROUND KBHK FROM 06 TO 12 UTC THOUGH...AND A FEW SHOWERS AND STORMS WITH LOCAL OBSCURATIONS ARE POSSIBLE IN AND AROUND THE MOUNTAINS MONDAY AFTERNOON. SCHULTZ && .PRELIMINARY POINT TEMP/POPS... MON TUE WED THU FRI SAT SUN ----------------------------------------------------------- BIL 065/100 070/096 064/089 062/085 061/088 064/091 062/085 10/U 22/T 10/B 11/U 11/U 11/U 11/B LVM 056/100 059/094 054/091 053/086 053/089 054/091 053/086 12/T 32/T 10/B 11/B 11/B 11/U 11/B HDN 059/102 065/098 060/091 061/087 060/090 062/094 061/087 10/G 22/T 10/B 11/U 11/U 11/U 11/B MLS 063/099 069/097 063/087 061/084 059/087 061/092 061/084 10/U 12/T 10/B 11/B 11/U 11/U 12/T 4BQ 061/097 065/094 063/086 061/083 058/086 061/091 061/084 20/U 12/T 10/B 21/B 11/U 11/U 12/T BHK 060/094 063/093 060/083 059/080 055/082 057/088 059/081 20/U 03/T 21/B 31/B 11/U 11/U 12/T SHR 057/095 060/093 058/086 057/082 054/083 056/088 056/083 20/U 12/T 11/B 22/T 11/B 11/U 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
834 PM MDT SUN JUN 28 2015 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... A FEW THUNDERSTORMS FORMED UP IN NORTHERN VALLEY COUNTY IN EARLY EVENING. BUT WHEN THEY MOVED INTO A MORE STABLE ENVIRONMENT THE STORMS QUICKLY COLLAPSED. THEREFORE REDUCED COVERAGE AND LOWERED POPS TO ISOLATED FOR THE REST OF THE EVENING. THERE ARE A FEW SMALL STORMS UPSTREAM...SO WILL NEED TO KEEPS SMALL POPS. OTHERWISE FEW OTHER GRID EDITS ARE NEEDED. SCT PREVIOUS UPDATE... DID A QUICK UPDATE TO ADD ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS BASED ON CONVECTION UPSTREAM...ONE OF WHICH CROSSED INTO NORTHERN VALLEY COUNTY FROM SASKATCHEWAN LATE THIS AFTERNOON. SCT PREVIOUS DISCUSSION... SYNOPTIC SET UP...A LARGE TROUGH EXIST OVER THE GREAT LAKES AND MIDWEST WHILE A LARGE HOT HIGH PRESSURE RIDGE RESIDES OVER THE WESTERN THIRD OF THE US. THE HIGH PLAINS INCLUDING NORTHEAST MONTANA RESIDE WEDGED IN BETWEEN THESE TWO FEATURES ON THE WARMER SIDE OF NORTHWEST FLOW ALOFT. THIS AFTERNOON THROUGH THIS EVENING... EC MODEL THIS AFTERNOON HAS TIPPED OFF WHAT SEVERAL OTHER HI-RES MODELS SUCH AS THE NAM AND HRRR ARE MASKING IN THEIR SURFACE QPF FIELDS WITH DRY SURFACE LAYERS. 500 TO 1000 J/KG OF CAPE EXISTS ACROSS THE CWA THIS AFTERNOON BUT IS SETTING ABOVE A 600-700 MB LAYER OF CAP. THE CHALLENGE WILL BE IN A SHORTWAVE COMING DOWN THROUGH THE NORTHWEST FLOW AND TRIGGERING SHOWERS. ONE DOES EXIST IN SEVERAL MODELS BUT TIMING AND PLACEMENT IS IMPRECISE FOR THE MINOR MID LEVEL DISTURBANCE. SO CONFIDENCE IS VERY LOW... IN ADDITION THE DRY SURFACE LAYER WILL LIKELY RAPIDLY CHEW THROUGH ANY NEW RAIN AND GENERATE MORE VIRGA THAT DROPS ON SURFACE. HENCE SPRINKLES IF ANYTHING AT ALL. MONDAY... RIDGE TOP WILL TRANSITION FROM IDAHO TO MONTANA FURTHER WARMING THE ATMOSPHERE AND LEADING TO HIGHS IN THE 90S WITH A FEW 100S POSSIBLE IN THE MISSOURI BREAKS. SHOULD BE DRY AND PARTLY CLOUDY TO CLEAR. MONDAY NIGHT THROUGH TUESDAY... AS THE RIDGE AXIS PASSES BY NORTHEAST MONTANA AND TOPPLES OVER INTO WYOMING A SHORTWAVE WILL BE ARRIVING ON THE BACKSIDE OF THE AXIS AND PUMPING IN COOL AIR ALOFT AND GENERATING A MOIST GULF INFLOW AT THE SURFACE FROM THE SOUTHEAST. THIS WILL DESTABILIZE THE ATMOSPHERE BY TUESDAY MORNING. SCATTERED GENERAL THUNDERSTORMS ARE LIKELY ACROSS THE AREA BUT SEVERE STORMS WILL BE HIGHLY DEPENDENT ON HOW MUCH COOLING WILL TAKE PLACE ALOFT. AT THIS TIME ONLY GENERAL THUNDERSTORMS RE ANTICIPATED... BUT THIS COULD RAPIDLY CHANGE AS NEW DATA IS INGESTED INTO UPPER AIR FOR THE MODELS. GAH .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... NO MAJOR CHANGES TO THE EXTENDED. JUST A FEW TWEAKS FOR COORDINATION PURPOSES. SURFACE LOW MOVES TO THE SOUTHEAST WITH AN INVERTED TROF LINGERING OVER EASTERN MONTANA. WE COULD SEE SOME LINGERING SHOWERS AND THUNDERSTORMS WITH THAT. THURSDAY AND FRIDAY BRING MOSTLY HOT AND DRY CONDITIONS AS A HIGH PRESSURE SYSTEM MOVES OVER THE AREA. SATURDAY BRINGS ANOTHER STRONG SURFACE LOW WITH THE POTENTIAL FOR STRONGER WINDS AS THE GRADIENT TIGHTENS UP. THE ONE ITEM NOT ADDRESSED IS THAT WE TYPICALLY SEE SOME SORT OF SHOWERS/THUNDERSTORMS WITH ANY FRONTAL PASSAGE BUT RIGHT NOW THINGS ARE NOT REALLY INDICATING THAT FOR THE FROPA ON SATURDAY EVENING. THAT IS SOMETHING TO KEEP AN EYE ON...IT WOULDN`T SUPRISE ME IF WE POPPED A FEW THUNDERSTORMS ALONG THE FRONTAL BOUNDARY. BREEZY WINDS IN STORE BEHIND THE FRONT ON SUNDAY. TEMPERATURES WILL STILL BE PRETTY WARM THROUGH THE FORECAST PERIOD...WITH READINGS GENERALLY IN THE 80S. FRANSEN PREVIOUS DISCUSSION...LOOK FOR NORTHWEST FLOW ALOFT DURING THE PERIOD AS UPPER LEVEL HIGH REMAINS IN PLACE IN THE DESERT SOUTHWEST AND AN UPPER TROUGH STAYS TO THE EAST. WITHIN THE NW FLOW ALOFT...THERE WILL BE A SHORTWAVE TROUGH THAT MOVES THROUGH NE MONTANA ON WEDNESDAY WITH A COLD FRONT. THE SYSTEM WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS. A WEAKER SHORTWAVE TROUGHS ON THURSDAY AND FRIDAY APPEARS TO BE LACKING MOISTURE AT THIS POINT. WILL KEEP FORECAST DRY. ALSO...IT LOOKS LIKE THE WARMER AIR MASS TO THE WEST WILL BE BROUGHT BACK EAST SO THAT THERE WILL BE A WARMING TREND IN THE TEMPERATURES. MODELS ARE POINTING TOWARDS A DEEPER UPPER TROUGH/LOW MOVING INTO THE CANADIAN PRAIRIES ON SATURDAY WITH A COLD FRONT THAT HAS LIMITED MOISTURE. MODELS DIFFER ON WHETHER IT WILL BE A WEAK COLD FRONT OR STRONG COLD FRONT AND HOW MUCH COOLING IS EXPECTED BEHIND THE FRONT. WILL MAINTAIN NEAR NORMAL TEMPERATURES AND A DRY FORECAST FOR NOW. SUNDAY LOOKS DRY WITH A HIGH PRESSURE SYSTEM OVER THE AREA. FORRESTER && .AVIATION... VFR. ISOLATED STORMS THAT WERE NORTH OF KGGW QUICKLY DIMINISHED AND MAINLY CLEAR SKIES ARE EXPECTED THE REST OF THE NIGHT WITH LIGHT AND VARIABLE WINDS. REMNANTS OF THUNDERSTORMS MOVING SE TOWARD CYQR (REGINA SASK) SHOULD PASS EAST OF THE AREA LATER TONIGHT. TFJ && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION...UPDATED
NWS GLASGOW MT
621 PM MDT SUN JUN 28 2015 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH TUESDAY... DID A QUICK UPDATE TO ADD ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS BASED ON CONVECTION UPSTREAM...ONE OF WHICH CROSSED INTO NORTHERN VALLEY COUNTY FROM SASKATCHEWAN LATE THIS AFTERNOON. SCT PREVIOUS DISCUSSION... SYNOPTIC SET UP...A LARGE TROUGH EXIST OVER THE GREAT LAKES AND MIDWEST WHILE A LARGE HOT HIGH PRESSURE RIDGE RESIDES OVER THE WESTERN THIRD OF THE US. THE HIGH PLAINS INCLUDING NORTHEAST MONTANA RESIDE WEDGED IN BETWEEN THESE TWO FEATURES ON THE WARMER SIDE OF NORTHWEST FLOW ALOFT. THIS AFTERNOON THROUGH THIS EVENING... EC MODEL THIS AFTERNOON HAS TIPPED OFF WHAT SEVERAL OTHER HI-RES MODELS SUCH AS THE NAM AND HRRR ARE MASKING IN THEIR SURFACE QPF FIELDS WITH DRY SURFACE LAYERS. 500 TO 1000 J/KG OF CAPE EXISTS ACROSS THE CWA THIS AFTERNOON BUT IS SETTING ABOVE A 600-700 MB LAYER OF CAP. THE CHALLENGE WILL BE IN A SHORTWAVE COMING DOWN THROUGH THE NORTHWEST FLOW AND TRIGGERING SHOWERS. ONE DOES EXIST IN SEVERAL MODELS BUT TIMING AND PLACEMENT IS IMPRECISE FOR THE MINOR MID LEVEL DISTURBANCE. SO CONFIDENCE IS VERY LOW... IN ADDITION THE DRY SURFACE LAYER WILL LIKELY RAPIDLY CHEW THROUGH ANY NEW RAIN AND GENERATE MORE VIRGA THAT DROPS ON SURFACE. HENCE SPRINKLES IF ANYTHING AT ALL. MONDAY... RIDGE TOP WILL TRANSITION FROM IDAHO TO MONTANA FURTHER WARMING THE ATMOSPHERE AND LEADING TO HIGHS IN THE 90S WITH A FEW 100S POSSIBLE IN THE MISSOURI BREAKS. SHOULD BE DRY AND PARTLY CLOUDY TO CLEAR. MONDAY NIGHT THROUGH TUESDAY... AS THE RIDGE AXIS PASSES BY NORTHEAST MONTANA AND TOPPLES OVER INTO WYOMING A SHORTWAVE WILL BE ARRIVING ON THE BACKSIDE OF THE AXIS AND PUMPING IN COOL AIR ALOFT AND GENERATING A MOIST GULF INFLOW AT THE SURFACE FROM THE SOUTHEAST. THIS WILL DESTABILIZE THE ATMOSPHERE BY TUESDAY MORNING. SCATTERED GENERAL THUNDERSTORMS ARE LIKELY ACROSS THE AREA BUT SEVERE STORMS WILL BE HIGHLY DEPENDENT ON HOW MUCH COOLING WILL TAKE PLACE ALOFT. AT THIS TIME ONLY GENERAL THUNDERSTORMS RE ANTICIPATED... BUT THIS COULD RAPIDLY CHANGE AS NEW DATA IS INGESTED INTO UPPER AIR FOR THE MODELS. GAH .LONG TERM...TUESDAY NIGHT THROUGH SUNDAY... NO MAJOR CHANGES TO THE EXTENDED. JUST A FEW TWEAKS FOR COORDINATION PURPOSES. SURFACE LOW MOVES TO THE SOUTHEAST WITH AN INVERTED TROF LINGERING OVER EASTERN MONTANA. WE COULD SEE SOME LINGERING SHOWERS AND THUNDERSTORMS WITH THAT. THURSDAY AND FRIDAY BRING MOSTLY HOT AND DRY CONDITIONS AS A HIGH PRESSURE SYSTEM MOVES OVER THE AREA. SATURDAY BRINGS ANOTHER STRONG SURFACE LOW WITH THE POTENTIAL FOR STRONGER WINDS AS THE GRADIENT TIGHTENS UP. THE ONE ITEM NOT ADDRESSED IS THAT WE TYPICALLY SEE SOME SORT OF SHOWERS/THUNDERSTORMS WITH ANY FRONTAL PASSAGE BUT RIGHT NOW THINGS ARE NOT REALLY INDICATING THAT FOR THE FROPA ON SATURDAY EVENING. THAT IS SOMETHING TO KEEP AN EYE ON...IT WOULDN`T SUPRISE ME IF WE POPPED A FEW THUNDERSTORMS ALONG THE FRONTAL BOUNDARY. BREEZY WINDS IN STORE BEHIND THE FRONT ON SUNDAY. TEMPERATURES WILL STILL BE PRETTY WARM THROUGH THE FORECAST PERIOD...WITH READINGS GENERALLY IN THE 80S. FRANSEN PREVIOUS DISCUSSION...LOOK FOR NORTHWEST FLOW ALOFT DURING THE PERIOD AS UPPER LEVEL HIGH REMAINS IN PLACE IN THE DESERT SOUTHWEST AND AN UPPER TROUGH STAYS TO THE EAST. WITHIN THE NW FLOW ALOFT...THERE WILL BE A SHORTWAVE TROUGH THAT MOVES THROUGH NE MONTANA ON WEDNESDAY WITH A COLD FRONT. THE SYSTEM WILL BRING A CHANCE OF SHOWERS AND THUNDERSTORMS. A WEAKER SHORTWAVE TROUGHS ON THURSDAY AND FRIDAY APPEARS TO BE LACKING MOISTURE AT THIS POINT. WILL KEEP FORECAST DRY. ALSO...IT LOOKS LIKE THE WARMER AIR MASS TO THE WEST WILL BE BROUGHT BACK EAST SO THAT THERE WILL BE A WARMING TREND IN THE TEMPERATURES. MODELS ARE POINTING TOWARDS A DEEPER UPPER TROUGH/LOW MOVING INTO THE CANADIAN PRAIRIES ON SATURDAY WITH A COLD FRONT THAT HAS LIMITED MOISTURE. MODELS DIFFER ON WHETHER IT WILL BE A WEAK COLD FRONT OR STRONG COLD FRONT AND HOW MUCH COOLING IS EXPECTED BEHIND THE FRONT. WILL MAINTAIN NEAR NORMAL TEMPERATURES AND A DRY FORECAST FOR NOW. SUNDAY LOOKS DRY WITH A HIGH PRESSURE SYSTEM OVER THE AREA. FORRESTER && .AVIATION... FLIGHT CATEGORY: VFR. SYNOPSIS: UPPER LEVEL RIDGE WILL CONTINUE TO BUILD INTO MONTANA WITH A WEAK WAVES CROSSING EXTREME NE MONTANA AND NW ND. EXPECT MOSTLY CLEAR SKIES TODAY AND TONIGHT WITH ONLY A FEW MID TO HIGH CLOUDS. WE COULD SEE A FEW CUMULUS POP TODAY WITH SOME VIRGA IN THE AREAS EAST/NORTH OF KOLF AND KSDY...BUT SHOWERS WOULD BE VERY ISOLATED AND NOT ENOUGH TO MENTION IN THE TAFS. WIND: LIGHT AND VARIABLE EXCEPT FOR THE LOCAL NOCTURNAL KGGW EAST WINDS AROUND 10 KNOTS. && .GLASGOW WATCHES/WARNINGS/ADVISORIES...NONE. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1245 PM CDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CDT SAT JUN 27 2015 QUIET WEATHER IS EXPECTED THROUGH THE SHORT TERM PERIODS WITH A SEASONABLY COOL MORNING FOLLOWED BY CONTINUED SEASONAL TEMPERATURES THIS AFTERNOON AND AGAIN OVERNIGHT TONIGHT. THE MAIN CHANGE TO THE SHORT TERM PORTION OF THE FORECAST THIS MORNING WAS TO INTRODUCE A SMALL CHANCE FOR SPRINKLES THIS AFTERNOON AS BOTH THE FORECAST MAXIMUM TEMPS AND CONVECTIVE TEMPS ARE IN THE LOWER TO MIDDLE 80S...WHICH MEANS WE SHOULD SEE SOME CUMULUS DEVELOPMENT DURING THE AFTERNOON HOURS...A FEW OF WHICH MAY GROW ENOUGH TO PRODUCE A FEW SPRINKLES. SOME MODEL DATA SUPPORTS THIS...WITH BOTH THE HRRR AND THE RAP INDICATING SOME SPLOTCHY LIGHT PRECIP IS POSSIBLE LATER TODAY. OTHER THAN INTRODUCING THE CHANCE FOR SPRINKLES THIS AFTERNOON...FEW CHANGES WERE MADE TO THE SHORT TERM FORECAST AS WITH SURFACE HIGH PRESSURE TRANSITIONING ACROSS THE LOCAL AREA...LIGHT WINDS ARE EXPECTED TO ACCOMPANY A FAIRLY SEASONABLE AIRMASS THAT IS IN PLACE ACROSS THE REGION. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 351 AM CDT SAT JUN 27 2015 MODELS REMAIN IN GOOD AGREEMENT AT THE START OF THE LONG TERM PERIOD...WITH A WELL AMPLIFIED UPPER LEVEL PATTERN ACROSS THE CONUS AT 12Z SUNDAY. THE PLAINS SITS UNDER NORTH/NORTHWESTERLY FLOW...IN BETWEEN HIGH PRESSURE/RIDGING EXTENDING WELL NORTH INTO WRN CANADA AND LOW PRESSURE MOVING INTO THE NERN CONUS. A WEAKER SHORTWAVE DISTURBANCE IS EXPECTED TO BE MOVING INTO NRN PORTIONS OF MN AT THE START OF THE DAY...WITH AN ACCOMPANYING WEST/SOUTHWESTWARD EXTENDING SFC FRONT MOVING INTO NRN NEB. THIS DISTURBANCE WILL BE THE MAIN STORY FOR SUNDAY...AND IS EXPECTED TO SLIDE SOUTH/SOUTHEAST INTO THE WI/IA/IN AREA BY EVENING. TIMING OF THE ACCOMPANYING FRONT HAS NOT CHANGED MUCH...WITH MODELS SHOWING IT PUSHING THROUGH ROUGHLY 2/3 OF THE CWA BY 18Z...AND NORTHERLY WINDS CWA-WIDE BY EVENING. THE FORECAST FOR SUNDAY REMAINS DRY...WITH MODELS CONTINUING TO KEEP THE BETTER CHANCES FOR PRECIP JUST OFF TO THE EAST OF THE CWA. THIS FRONT USHERS IN THOSE NRLY WINDS AND KEEPS DPTS ON THE NICER SIDE IN THE 50S DURING THE AFTERNOON...BUT DOESNT BRING IN A NOTABLE COOLER AIRMASS. HIGHS FOR SUNDAY ARE FORECAST TO RANGE FROM THE MID 80S NORTH TO LOWER 90S SOUTH. THE FORECAST FOR THE START OF THE NEXT WORK WEEK /MON AND TUES/ REMAIN DRY. NOT EXPECTING A LOT OF CHANGE IN THE UPPER LEVEL PATTERN ON MONDAY...BUT A COUPLE SHOTS OF UPPER LEVEL SHORTWAVE ENERGY LOOK TO BE MOVING INTO THE PAC NW REGION...AND AS WE GET INTO MONDAY NIGHT/TUESDAY...SLIDE THROUGH THE MAIN FLOW AROUND THE EDGE OF THE RIDGE...CAUSING IT TO DEAMPLIFY A BIT. AT THE SURFACE...THE PATTERN ACROSS THE AREA IS ON THE WEAKER SIDE AS HIGHER PRESSURE BUILDS IN BEHIND SUNDAYS FRONTAL PASSAGE...WITH S/SWRLY RETURN FLOW DEVELOPING MON NIGHT/TUES AS LOW PRESSURE BECOMES BETTER ORGANIZED THROUGH THE HIGH PLAINS. UPPER 80S TO MID 90S ARE IN THE FORECAST FOR HIGHS. MORE UNCERTAINTY IN THE FORECAST STARTS TO BUILD AS WE GET INTO THE MIDDLE/END PORTIONS OF THE WORK WEEK...AS THOSE ABOVE MENTIONED UPPER LEVEL DISTURBANCE MAKE THEIR WAY SOUTHEAST THROUGH THE PLAINS. THIS WILL BRING A RETURN OF THUNDERSTORM CHANCES STARTING TUESDAY NIGHT AND CONTINUING THROUGH FRIDAY. CONFIDENCE IN THE TIMING LOWERS THE FURTHER OUT IN TIME THE FORECAST GOES...PLENTY OF THINGS TO IRON OUT IN THE COMING DAYS. HIGHS WED THROUGH FRI REMAIN IN THE 80S FOR MOST LOCATIONS. && .AVIATION...(FOR THE 18Z KGRI/KEAR TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1240 PM CDT SAT JUN 27 2015 CUMULUS FIELD AROUND 5K WILL BE NOTED THIS AFTERNOON IN THE KGRI AND KEAR REGION. WINDS WILL REMAIN LIGHT AND EVENTUALLY TURN TO THE SOUTH THIS EVENING BUT REMAIN. ON SUNDAY MORNING...A FRONT WILL PUSH THROUGH AND SHIFT WINDS TO THE NORTHWEST AT NEAR 15KTS BUT LITTLE OTHER WEATHER IMPACTS ARE EXPECTED...WITH ONLY A FEW CLOUDS ALONG THE FRONT AT MOST. NO VISIBILITY RESTRICTIONS ARE FORECAST. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ROSSI LONG TERM...ADP AVIATION...NOAA/NWS/MORITZ
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1227 PM CDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 350 AM CDT SAT JUN 27 2015 A DISTURBANCE ACROSS THE NORTHERN PLAINS WILL PULL A REINFORCING PACIFIC INTO THE FCST AREA LATE TONIGHT. WINDS TODAY BECOME LIGHT WEST AND SOUTHWEST AHEAD OF THE FRONT WITH MODEST WARM AIR ADVECTION. THE RAP SUGGESTED H750MB TEMPERATURES IN THE TEENS TODAY WHICH SUPPORTS HIGHS IN THE MID TO UPPER 80S. NO RETURN MOISTURE IS EXPECTED AHEAD OF THE FRONT SO DEW POINTS REMAIN IN THE 50S TODAY AND TONIGHT. LIGHT NORTHWEST WINDS AND GENERALLY CLEAR SKIES TONIGHT WOULD SUPPORT DRAINAGE WINDS AND LOWS IN THE MID 50S TO NEAR 60. POSSIBLY COOLER THOUGH GIVEN THE MET AND MAV GUIDANCE ARE TRENDING TOWARD THE LOWER 50S. LATER FORECASTS MAY NEED TO BUMP LOWS DOWN TONIGHT. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 350 AM CDT SAT JUN 27 2015 WESTERN RIDGE DOMINATES THE LONG TERM FORECAST...WITH NORTHWEST FLOW THE CONTINUING THROUGH THE WEEK. LITTLE MOISTURE TO WORK WITH INITIALLY AND A DRY START TO THE WEEK IS EXPECTED. MODELS IN AGREEMENT BRINGING A STRONGER SHORT WAVE/LOW PRESSURE SYSTEM ACROSS THE AREA TUESDAY INTO WEDNESDAY. AHEAD OF THE COLD FRONT SOME COMPRESSIONAL HEATING SHOULD CAUSE TEMPS TO SURGE UPWARD A FEW DEGREES WITH MOST SITES IN THE UPPER 80S TO LOWER 90S. FAR SW NEB COULD SEE TEMPS IN THE MID 90S. ALONG AND BEHIND THE FRONT IS A CHANCE FOR STORMS. UNCERTAINTY ABOUT MOISTURE AVAILABILITY AND STORM COVERAGE...THUS LIMITED CHANGE TO ONGOING LOW CHANCE POPS. SLIGHT COOL DOWN BEHIND THE FRONT WITH ANOTHER WAVE QUICKLY FOLLOWING. LOW POPS CONTINUE INTO THURSDAY NIGHT BEFORE THE RIDGE EXPANDS AGAIN AND WAVES GET PUSHED TO THE NORTHEAST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1225 PM CDT SAT JUN 27 2015 VISUAL FLIGHT RULES FORECASTED THROUGH 18Z SUNDAY AT TERMINALS KLBF AND KVTN. MODELS IN GOOD AGREEMENT WHERE A COLD FRONT WILL ENTER THE FAR NORTHWEST PANHANDLE THIS EVENING AND PROCEED TO MOVE SOUTHEAST TO NEAR A LINE FROM VTN TO OGA BY MIDNIGHT. LIGHT WINDS AND LITTLE MOISTURE WILL ACCOMPANY THE BOUNDARY FOR FEW CLOUDS THROUGH THE PERIOD. && .LBF WATCHES/WARNINGS/ADVISORIES..NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...KECK
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
614 AM CDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 350 AM CDT SAT JUN 27 2015 A DISTURBANCE ACROSS THE NORTHERN PLAINS WILL PULL A REINFORCING PACIFIC INTO THE FCST AREA LATE TONIGHT. WINDS TODAY BECOME LIGHT WEST AND SOUTHWEST AHEAD OF THE FRONT WITH MODEST WARM AIR ADVECTION. THE RAP SUGGESTED H750MB TEMPERATURES IN THE TEENS TODAY WHICH SUPPORTS HIGHS IN THE MID TO UPPER 80S. NO RETURN MOISTURE IS EXPECTED AHEAD OF THE FRONT SO DEW POINTS REMAIN IN THE 50S TODAY AND TONIGHT. LIGHT NORTHWEST WINDS AND GENERALLY CLEAR SKIES TONIGHT WOULD SUPPORT DRAINAGE WINDS AND LOWS IN THE MID 50S TO NEAR 60. POSSIBLY COOLER THOUGH GIVEN THE MET AND MAV GUIDANCE ARE TRENDING TOWARD THE LOWER 50S. LATER FORECASTS MAY NEED TO BUMP LOWS DOWN TONIGHT. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 350 AM CDT SAT JUN 27 2015 WESTERN RIDGE DOMINATES THE LONG TERM FORECAST...WITH NORTHWEST FLOW THE CONTINUING THROUGH THE WEEK. LITTLE MOISTURE TO WORK WITH INITIALLY AND A DRY START TO THE WEEK IS EXPECTED. MODELS IN AGREEMENT BRINGING A STRONGER SHORT WAVE/LOW PRESSURE SYSTEM ACROSS THE AREA TUESDAY INTO WEDNESDAY. AHEAD OF THE COLD FRONT SOME COMPRESSIONAL HEATING SHOULD CAUSE TEMPS TO SURGE UPWARD A FEW DEGREES WITH MOST SITES IN THE UPPER 80S TO LOWER 90S. FAR SW NEB COULD SEE TEMPS IN THE MID 90S. ALONG AND BEHIND THE FRONT IS A CHANCE FOR STORMS. UNCERTAINTY ABOUT MOISTURE AVAILABILITY AND STORM COVERAGE...THUS LIMITED CHANGE TO ONGOING LOW CHANCE POPS. SLIGHT COOL DOWN BEHIND THE FRONT WITH ANOTHER WAVE QUICKLY FOLLOWING. LOW POPS CONTINUE INTO THURSDAY NIGHT BEFORE THE RIDGE EXPANDS AGAIN AND WAVES GET PUSHED TO THE NORTHEAST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 614 AM CDT SAT JUN 27 2015 AN UPPER LEVEL DISTURBANCE ACROSS THE NRN PLAINS WILL DRAW HIGH PRESSURE ACROSS ALBERTA INTO THE CNTL PLAINS TONIGHT. VFR IS EXPECTED ALL AREAS. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...CDC
AREA FORECAST DISCUSSION
NWS HASTINGS NE
355 AM CDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CDT SAT JUN 27 2015 QUIET WEATHER IS EXPECTED THROUGH THE SHORT TERM PERIODS WITH A SEASONABLY COOL MORNING FOLLOWED BY CONTINUED SEASONAL TEMPERATURES THIS AFTERNOON AND AGAIN OVERNIGHT TONIGHT. THE MAIN CHANGE TO THE SHORT TERM PORTION OF THE FORECAST THIS MORNING WAS TO INTRODUCE A SMALL CHANCE FOR SPRINKLES THIS AFTERNOON AS BOTH THE FORECAST MAXIMUM TEMPS AND CONVECTIVE TEMPS ARE IN THE LOWER TO MIDDLE 80S...WHICH MEANS WE SHOULD SEE SOME CUMULUS DEVELOPMENT DURING THE AFTERNOON HOURS...A FEW OF WHICH MAY GROW ENOUGH TO PRODUCE A FEW SPRINKLES. SOME MODEL DATA SUPPORTS THIS...WITH BOTH THE HRRR AND THE RAP INDICATING SOME SPLOTCHY LIGHT PRECIP IS POSSIBLE LATER TODAY. OTHER THAN INTRODUCING THE CHANCE FOR SPRINKLES THIS AFTERNOON...FEW CHANGES WERE MADE TO THE SHORT TERM FORECAST AS WITH SURFACE HIGH PRESSURE TRANSITIONING ACROSS THE LOCAL AREA...LIGHT WINDS ARE EXPECTED TO ACCOMPANY A FAIRLY SEASONABLE AIRMASS THAT IS IN PLACE ACROSS THE REGION. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 351 AM CDT SAT JUN 27 2015 MODELS REMAIN IN GOOD AGREEMENT AT THE START OF THE LONG TERM PERIOD...WITH A WELL AMPLIFIED UPPER LEVEL PATTERN ACROSS THE CONUS AT 12Z SUNDAY. THE PLAINS SITS UNDER NORTH/NORTHWESTERLY FLOW...IN BETWEEN HIGH PRESSURE/RIDGING EXTENDING WELL NORTH INTO WRN CANADA AND LOW PRESSURE MOVING INTO THE NERN CONUS. A WEAKER SHORTWAVE DISTURBANCE IS EXPECTED TO BE MOVING INTO NRN PORTIONS OF MN AT THE START OF THE DAY...WITH AN ACCOMPANYING WEST/SOUTHWESTWARD EXTENDING SFC FRONT MOVING INTO NRN NEB. THIS DISTURBANCE WILL BE THE MAIN STORY FOR SUNDAY...AND IS EXPECTED TO SLIDE SOUTH/SOUTHEAST INTO THE WI/IA/IN AREA BY EVENING. TIMING OF THE ACCOMPANYING FRONT HAS NOT CHANGED MUCH...WITH MODELS SHOWING IT PUSHING THROUGH ROUGHLY 2/3 OF THE CWA BY 18Z...AND NORTHERLY WINDS CWA-WIDE BY EVENING. THE FORECAST FOR SUNDAY REMAINS DRY...WITH MODELS CONTINUING TO KEEP THE BETTER CHANCES FOR PRECIP JUST OFF TO THE EAST OF THE CWA. THIS FRONT USHERS IN THOSE NRLY WINDS AND KEEPS DPTS ON THE NICER SIDE IN THE 50S DURING THE AFTERNOON...BUT DOESNT BRING IN A NOTABLE COOLER AIRMASS. HIGHS FOR SUNDAY ARE FORECAST TO RANGE FROM THE MID 80S NORTH TO LOWER 90S SOUTH. THE FORECAST FOR THE START OF THE NEXT WORK WEEK /MON AND TUES/ REMAIN DRY. NOT EXPECTING A LOT OF CHANGE IN THE UPPER LEVEL PATTERN ON MONDAY...BUT A COUPLE SHOTS OF UPPER LEVEL SHORTWAVE ENERGY LOOK TO BE MOVING INTO THE PAC NW REGION...AND AS WE GET INTO MONDAY NIGHT/TUESDAY...SLIDE THROUGH THE MAIN FLOW AROUND THE EDGE OF THE RIDGE...CAUSING IT TO DEAMPLIFY A BIT. AT THE SURFACE...THE PATTERN ACROSS THE AREA IS ON THE WEAKER SIDE AS HIGHER PRESSURE BUILDS IN BEHIND SUNDAYS FRONTAL PASSAGE...WITH S/SWRLY RETURN FLOW DEVELOPING MON NIGHT/TUES AS LOW PRESSURE BECOMES BETTER ORGANIZED THROUGH THE HIGH PLAINS. UPPER 80S TO MID 90S ARE IN THE FORECAST FOR HIGHS. MORE UNCERTAINTY IN THE FORECAST STARTS TO BUILD AS WE GET INTO THE MIDDLE/END PORTIONS OF THE WORK WEEK...AS THOSE ABOVE MENTIONED UPPER LEVEL DISTURBANCE MAKE THEIR WAY SOUTHEAST THROUGH THE PLAINS. THIS WILL BRING A RETURN OF THUNDERSTORM CHANCES STARTING TUESDAY NIGHT AND CONTINUING THROUGH FRIDAY. CONFIDENCE IN THE TIMING LOWERS THE FURTHER OUT IN TIME THE FORECAST GOES...PLENTY OF THINGS TO IRON OUT IN THE COMING DAYS. HIGHS WED THROUGH FRI REMAIN IN THE 80S FOR MOST LOCATIONS. && .AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1245 AM CDT SAT JUN 27 2015 VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR AT LEAST THE NEXT 24 HOURS. EXPECT MAINLY CLOUD FREE SKIES AND LIGHT WINDS AS AN AREA OF SURFACE HIGH PRESSURE TRANSITIONS ACROSS THE CENTRAL PLAINS... RESULTING IN A WEAK PRESSURE GRADIENT. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ROSSI LONG TERM...ADP AVIATION...ROSSI
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
350 AM CDT SAT JUN 27 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 350 AM CDT SAT JUN 27 2015 A DISTURBANCE ACROSS THE NORTHERN PLAINS WILL PULL A REINFORCING PACIFIC INTO THE FCST AREA LATE TONIGHT. WINDS TODAY BECOME LIGHT WEST AND SOUTHWEST AHEAD OF THE FRONT WITH MODEST WARM AIR ADVECTION. THE RAP SUGGESTED H750MB TEMPERATURES IN THE TEENS TODAY WHICH SUPPORTS HIGHS IN THE MID TO UPPER 80S. NO RETURN MOISTURE IS EXPECTED AHEAD OF THE FRONT SO DEW POINTS REMAIN IN THE 50S TODAY AND TONIGHT. LIGHT NORTHWEST WINDS AND GENERALLY CLEAR SKIES TONIGHT WOULD SUPPORT DRAINAGE WINDS AND LOWS IN THE MID 50S TO NEAR 60. POSSIBLY COOLER THOUGH GIVEN THE MET AND MAV GUIDANCE ARE TRENDING TOWARD THE LOWER 50S. LATER FORECASTS MAY NEED TO BUMP LOWS DOWN TONIGHT. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 350 AM CDT SAT JUN 27 2015 WESTERN RIDGE DOMINATES THE LONG TERM FORECAST...WITH NORTHWEST FLOW THE CONTINUING THROUGH THE WEEK. LITTLE MOISTURE TO WORK WITH INITIALLY AND A DRY START TO THE WEEK IS EXPECTED. MODELS IN AGREEMENT BRINGING A STRONGER SHORT WAVE/LOW PRESSURE SYSTEM ACROSS THE AREA TUESDAY INTO WEDNESDAY. AHEAD OF THE COLD FRONT SOME COMPRESSIONAL HEATING SHOULD CAUSE TEMPS TO SURGE UPWARD A FEW DEGREES WITH MOST SITES IN THE UPPER 80S TO LOWER 90S. FAR SW NEB COULD SEE TEMPS IN THE MID 90S. ALONG AND BEHIND THE FRONT IS A CHANCE FOR STORMS. UNCERTAINTY ABOUT MOISTURE AVAILABILITY AND STORM COVERAGE...THUS LIMITED CHANGE TO ONGOING LOW CHANCE POPS. SLIGHT COOL DOWN BEHIND THE FRONT WITH ANOTHER WAVE QUICKLY FOLLOWING. LOW POPS CONTINUE INTO THURSDAY NIGHT BEFORE THE RIDGE EXPANDS AGAIN AND WAVES GET PUSHED TO THE NORTHEAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1137 PM CDT FRI JUN 26 2015 ONLY A FEW CIRRUS CLOUDS CAN BE EXPECTED OVER CENTRAL AND WESTERN NEBRASKA TONIGHT AND THROUGH SATURDAY...SO CEILING AND VISIBILITY WILL BE UNRESTRICTED. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MASEK AVIATION...SPRINGER
AREA FORECAST DISCUSSION...UPDATED
NWS ALBUQUERQUE NM
1145 PM MDT FRI JUN 26 2015 .AVIATION... 06Z TAF CYCLE SHOWER AND THUNDERSTORM ACTIVITY WILL CONTINUE MAINLY ALONG THE EAST SLOPES OF THE CENTRAL MOUNTAIN CHAIN AS WELL AS OVER CIBOLA...VALENCIA AND SOCORRO COUNTIES INTO THE EARLY MORNING HOURS SATURDAY. MOIST ATMOSPHERE AND ELY UPSLOPE FLOW WILL ALLOW FOR BRIEF MVFR CONDITIONS AND MTN OBSCURATIONS AS WELL AS LCL IFR CIGS ALONG EAST SLOPES OF CENTRAL MTNS INCLUDING KLVS. MODERATE EAST CANYON WINDS WILL CONTINUE THROUGH TIJERAS CANYON AND IMPACT KABQ UNTIL APPROXIMATELY 09Z SATURDAY WITH GUSTS TO 30KT POSSIBLE. PRIMARY FOCUS FOR AFTERNOON AND EVENING STORMS SATURDAY WILL BE FROM THE SW MTNS NORTH ALONG THE CONTINENTAL DIVIDE TO THE WEST- CENTRAL MTNS. 33 && .PREV DISCUSSION...950 PM MDT FRI JUN 26 2015... .UPDATE... DECIDED TO HANG ONTO THE FLASH FLOOD WATCH AS HRRR AND RAP CONTINUE TO INDICATE PRECIPITATION DEVELOPING ALONG THE EAST SLOPES AND ADJACENT HIGHLANDS AS THE NIGHT PROGRESSES. HOWEVER 00Z NAM12 NOT AS CONVINCING FOR KEEPING THE WATCH...INDICATING LESS QPF. OTHERWISE TWEAKED THE EAST CANYON WINDS DOWNWARD WITH CONVECTION OCCURRING AND MOVING SOUTH AND WESTWARD OF THE CENTRAL MT CHAIN. UPDATED ZFP ALREADY TRANSMITTED. && .PREV DISCUSSION...313 PM MDT FRI JUN 26 2015... .SYNOPSIS... THOUGH STORMS HAVE BEEN SLOW TO START THIS AFTERNOON...THEY ARE EXPECTED TO INCREASE IN COVERAGE THIS EVENING. STORM MOTIONS WILL BE SLOW AND HEAVY RAIN IS POSSIBLE. THANKS TO THE BACK DOOR FRONT AND ASSOCIATED MOISTURE SURGE FROM TODAY...AN ACTIVE PATTERN IS EXPECTED FOR THE WEEKEND INTO MONDAY WITH WIDESPREAD STORMS PRODUCING HEAVY RAINFALL. AREAS OF FLASH FLOODING WILL BE POSSIBLE. STORM COVERAGE WILL TREND DOWNWARD ON TUESDAY...BUT WILL RAMP BACK UP LATER IN THE WEEK. && .DISCUSSION... BACK DOOR COLD FRONT NUDGED UP TO THE CENTRAL MOUNTAIN CHAIN THIS MORNING...AND HAS BEEN STUCK THERE SINCE. LATEST HRRR SUGGESTS IT MAY BE A FEW HOURS YET UNTIL THE FRONT IS ABLE TO PUSH THROUGH THE GAPS OF THE CENTRAL MOUNTAIN CHAIN...BUT SHOULD OCCUR BY 02-03Z. WHEN THAT DOES OCCUR...COULD SEE SOME STORMS DEVELOP IN THE ABQ METRO AREA. MEANWHILE...DUE TO THE FRONTS EARLY ARRIVAL...IT HAS TAKEN A BIT FOR STORMS TO DEVELOP SINCE AREAS ALONG THE EAST SLOPES HAVE NOT YET REACHED THERE CONVECTIVE TEMPERATURE. THIS WILL OCCUR LATER THIS AFTERNOON...AND STORMS ARE EXPECTED TO ROLL SOUTH OFF THE HIGHER TERRAIN INTO THE CENTRAL HIGH PLAINS. THE HRRR SHOWS STORMS FURTHER EAST...BUT THE NAM MAKES MORE SENSE AT THIS POINT THAT UPSLOPE FLOW AND OROGRAPHICS WILL BE THE MAIN TRIGGER FOR STORMS AND STORM MOTION WILL TAKE THEM SLOWLY SOUTH...IF NOT SW. MOISTURE VALUES LOOK TO BE AROUND 125 PERCENT OF NORMAL...THUS STORMS WILL BE CAPABLE OF PRODUCING HEAVY RAIN. THEREFORE...THE FLASH FLOOD WATCH WILL REMAIN INTACT...BUT CERTAINLY BEARS WATCHING. STORMS SHOULD INITIATE A BIT EARLIER ON SATURDAY...AND FAVOR THE HIGH TERRAIN INITIALLY. STORM MOTIONS WILL BE SLOW ONCE AGAIN... ESPECIALLY ACROSS WESTERN NM. GIVEN HOW WARM IT IS EXPECTED TO BE...WOULD NOT BE SURPRISED TO SEE SOME STRONG OUTFLOW WINDS FROM THESE STORMS. OTHERWISE...HEAVY RAIN WILL BE THE MAIN THREAT. PENDING HOW MODELS TREND TONIGHT...THE MIDNIGHT SHIFT MAY NEED TO ISSUE A FLASH FLOOD WATCH FOR PORTIONS OF WESTERN AND CENTRAL NM. THE ACTIVE PERIOD STILL LOOKS TO CONTINUE THROUGH MONDAY. RELATIVELY SLOW STORM MOTIONS AND HEAVY RAIN POTENTIAL WILL CONTINUE AS PWATS RAISE TO ABOUT 1 INCH OR BETTER ACROSS THE AREA. SOME RELIEF STILL LOOKS TO COME ON TUESDAY AS DRIER AIR ROUNDS THE UPPER HIGH INTO THE STATE. STILL ENOUGH MOISTURE FOR STORMS TO DEVELOP OVER THE MOUNTAINS...BUT OVERALL STORM COVERAGE SHOULD DECREASE SOME. COULD SEE A FEW MORE HAIL PRODUCING STORMS THOUGH VS MAINLY RAIN. MODELS NOW SHOWING A BACK DOOR FRONT/WIND SHIFT ON WEDNESDAY... RATHER THAN THURSDAY...WHICH MAY RESULT IN WEDNESDAY BEING A LITTLE MORE ACTIVE THAT THOUGHT YESTERDAY...ESPECIALLY ACROSS THE NE. A MUCH STRONGER FRONT LOOKS TO ARRIVE NEXT FRIDAY AND SATURDAY...AS A SHORTWAVE TROUGH SLIDES ACROSS COLORADO IN NW FLOW. THIS WILL BE JUST IN TIME FOR 4TH OF JULY FESTIVITIES. STAY TUNED. 34 && .FIRE WEATHER... WETTING SHOWERS AND THUNDERSTORMS WILL CONTINUE TO BE ACTIVE THROUGH THE WEEKEND INTO THE EARLY HALF OF NEXT WEEK. TEMPERATURES WILL RANGE NEAR TO BELOW NORMAL FOLLOWING AN INCREASE IN SURFACE MOISTURE. STORM MOTIONS WILL BE SLOW MOVING INCREASING FLASH FLOODING POTENTIAL...ESPECIALLY EAST OF THE CENTRAL MOUNTAIN CHAIN. THE FOUR CORNERS WILL BE THE LEAST ACTIVE FOR THE NEXT SEVERAL DAYS. TUESDAY AND WEDNESDAY WILL SEE A SLIGHT DOWNTREND IN STORM ACTIVITY AND UPTICK IN TEMPERATURES. ANOTHER BACK DOOR COLD FRONT SHOULD REPLENISH MOISTURE LATER NEXT WEEK. WETTING SHOWERS AND THUNDERSTORMS WILL CONTINUE THIS AFTERNOON INTO THE EVENING ACROSS MUCH OF CENTRAL AND EASTERN NEW MEXICO. THUNDERSTORM COVERAGE WILL BE HIGHER THAN PREVIOUS BECAUSE OF A BACK DOOR FRONT SLOWLY PUSHING SOUTH/WESTWARD TOWARD THE CENTRAL MOUNTAIN CHAIN. A DEEP SURGE IN MOISTURE WILL FOLLOW THE BACK DOOR COLD FRONT AS IT PUSHES WESTWARD INCREASING THUNDERSTORM CHANCES WITH HEAVY RAINFALL. GUSTY GAP WINDS WILL BE EXPECTED LATE TONIGHT WITHIN THE CENTRAL RIO GRANDE VALLEY...ALTHOUGH THE FORECAST TIMING FOR THE GAP WINDS WILL BE A BIT TRICKY SINCE THE FRONT IS MOVING SLOWER THAN ANTICIPATED. STORM MOTION WILL BE SLOW MOVING FROM NORTHEAST TO SOUTHWEST OVER THE NEXT 24 HOUR...INCREASING FLASH FLOODING POTENTIAL FOR AREAS EAST OF THE CENTRAL MOUNTAIN CHAIN TONIGHT...THEN EXPANDING TO CENTRAL AND WESTERN AREAS OVER THE WEEKEND. LOW LEVEL MOISTURE WILL CONTINUE TO PUSH TOWARD THE CONTINENTAL DIVIDE BY SATURDAY INCREASING WET THUNDERSTORMS FOR CENTRAL AND WESTERN NEW MEXICO. THE HIGHER THUNDERSTORM COVERAGE TREND SHOULD CONTINUE INTO EARLY NEXT WEEK. BASED ON THE UPPER HIGH POSITION THE STEERING FLOW SHOULD BE NORTHERLY FOR THE STORMS. TEMPERATURES WILL BE COOLER WITH HIGHER RELATIVE HUMIDITY VALUES. BY TUESDAY....STORMS WILL DOWNTREND A BIT BECAUSE OF DRIER MID LEVEL AIR ROTATING AROUND THE UPPER LEVEL HIGH. THIS DRIER TREND WILL NOT ELIMINATE STORM CHANCES. STORM CHANCES SHOULD INCREASE BY THURSDAY DUE TO A BACK DOOR COLD FRONT. 32 && .ABQ WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL 4 AM MDT SATURDAY FOR THE FOLLOWING ZONES... NMZ515-523-526-528-529-532-533-537>539. && $$ 99
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
1030 PM EDT SUN JUN 28 2015 .SYNOPSIS... RAIN SHOWERS WILL CONTINUE OVERNIGHT INTO TOMORROW MORNING AS A MID-LEVEL LOW PUSHES ACROSS THE NORTH COUNTRY. DRIER CONDITIONS BRIEFLY RETURN FOR THE LATTER HALF OF MONDAY THROUGH EARLY TUESDAY MORNING, FOLLOWED BY ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS TUESDAY AND WEDNESDAY. THE WORK WEEK WILL START WITH BELOW NORMAL TEMPERATURES AND TREND TO SLIGHTLY BELOW TO NEAR NORMAL BY MID WEEK. && .NEAR TERM /UNTIL 8 AM MONDAY MORNING/... AS OF 1025 PM EDT SUNDAY...UPDATE TO DROP FLOOD WATCH AS WIDESPREAD RAIN HAS EXITED THE REGION AND RIVERS AND STREAMS ONLY RESPONDED SLIGHTLY. MOST ARE CRESTING NOW AND FALLING SO EVEN WITH ANY ADDITIONAL LIGHT RAIN THROUGH THE NIGHT WE SHOULDN`T HAVE ANY ISSUES. CURRENT RADAR CONTINUES TO SHOW SOME LIGHT RETURNS LIKELY IN THE FORM OF DRIZZLE OR LIGHT RAIN. LATEST 3KM HRRR DOES SHOW SOME ADDITIONAL SHOWER DEVELOPMENT ACROSS NORTHERN NEW YORK OVER THE NEXT FEW HOURS THOUGH AS THE UPPER LOW PUSHES THROUGH THE ST LAWRENCE VALLEY SO HAVE KEPT IN SOME LIKELY POPS THERE, BUT LOWERED EVERYWHERE ELSE AS PRECIP WILL BE MORE SCATTERED IN NATURE. OVERNIGHT LOWS WILL RANGE IN THE 50S. && .SHORT TERM /8 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... AS OF 325 PM EDT SUNDAY...CYCLONIC FLOW CONTINUE TO PRODUCE SOME LINGERING SHOWERS MONDAY MORNING. THE AFTERNOON WILL SEE SURFACE RIDGING AS THE 500MB LOW EXITS EAST AND ANTICYCLONIC FLOW FILTERS INTO THE NORTH COUNTRY. THIS WILL RESULT IN A DRYING TREND MONDAY AFTERNOON INTO MONDAY NIGHT. SOME AREAS COULD SEE SOME SUN BREAKING THROUGH LATE IN THE DAY. MAX TEMPERATURES WILL GENERALLY BE IN THE 60S. SOME INCREASING CLOUDS AHEAD OF THE NEXT SYSTEM MAY LIMIT SOME FOG DEVELOPMENT MONDAY NIGHT, BUT DIMINISHING WINDS WILL AID FOG DEVELOPMENT IN AT LEAST THE CLIMATOLOGICALLY FAVORABLE AREAS. MIN TEMPERATURES WILL BE IN THE 40S TO MID 50S. TUESDAY WILL SEE AN INCREASE IN INSTABILITY WITH CAPE VALUES GREATER THAN 500 J/KG AFFECTING SOUTHWEST PORTIONS OF THE AREA AS A 500MB TROUGH MOVES EASTWARD ACROSS THE CENTRAL GREAT LAKES REGION. THE ASSOCIATED SURFACE LOW WILL BRING A WARM FRONT, RAIN SHOWERS AND POSSIBLY A THUNDERSTORM ACROSS THE REGION DURING THE DAY. 850MB TEMPERATURES WILL REACH THE MID TEENS, RESULTING IN MORE SEASONABLE MAX TEMPERATURES. SHOWERS AND THUNDERSTORMS CONTINUE INTO TUESDAY NIGHT AS THE SURFACE LOW MOVES NORTHEASTWARD INTO SOUTHERN QUEBEC WITH UPPER LEVEL JET ENHANCING LIFT AND PROLONGING THREAT FOR THUNDERSTORMS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 325 PM EDT SUNDAY...LONGWAVE PATTERN REMAINS WELL-SPECIFIED IN THE EXTENDED PERIOD, WITH THE NORTH COUNTRY CONTINUES IN MEAN CYCLONIC FLOW ALOFT. IT`S A GENERALLY UNSETTLED PERIOD WITH A SERIES OF EMBEDDED SHORTWAVE TROUGHS/VORT MAXES PROGGED TO IMPACT THE NORTH COUNTRY. HOWEVER, THERE IS LESS CLARITY NOTED IN 12Z NWP SUITE THAN PRIOR CYCLES REGARDING TIMING AND AMPLITUDE OF AFOREMENTIONED SHORTWAVES. I`VE OPTED TO USE A HEAVY DOSE OF BLENDED GUIDANCE FOR THIS PERIOD. DAILY DETAILS FOLLOW... WEDNESDAY: LOOKS TO BE THE MOST ACTIVE IN THE PERIOD AS A DIGGING SHORTWAVE INTO OHIO VALLEY REGION CARVES OUT MEAN SOUTHWEST FLOW ALOFT ACROSS NORTH COUNTRY. THAT ALLOWS FOR A PLUME OF RELATIVELY HIGH PWAT AIR (UP TO 1.5 INCHES) TO ADVECT NORTHEASTWARD PARALLEL TO SFC COLD FRONTAL BOUNDARY. PER 12Z GFS, WARM SECTOR AIRMASS CHARACTERIZED BY LI`S OF -4 AND CAPE VALUES AOB 1000 J/KG, WITH DEEP LAYER SHEAR VALUES 35-40 KTS. SO THERE COULD BE A WINDOW FOR STRONGER THUNDERSTORMS WITH LOCALLY HEAVY RAIN/HYDRO CONCERNS WEDNESDAY AFTN/EVENING. KEPT POPS HIGH LIKELY/LOW CATEGORICAL FOR VT AND CLOSER TO LIKELY FOR NORTHER NY. SHOWN FORECAST QPF WEDNESDAY UP TO A HALF INCH, BUT LOCALLY MORE IN CONVECTION. DEPENDING ON SPEED THAT FRONT EXITS - WHICH MAY TURN OUT TO BE SLOWER - SHOULD HAVE POST-FRONTAL CAA REGIME WEDNESDAY NIGHT. HIGHS IN THE 70S WITH LOWS IN THE M50S/NEAR 60. THURSDAY: GFS/EC REALLY ARE AT ODDS WITH REGARD TO HOW THURSDAY PLAYS OUT. THE GFS DEPICTS AN AMPLIFYING SHORTWAVE WITH LARGER QPF ON THURSDAY, WHILE THE EC SHOWS MORE SHEARED-OUT SHORTWAVE FEATURES AND LOWER QPF. KEPT IDEA OF SLIGHT CHANCE TO CHANCE POPS FOR THURSDAY. FRIDAY LOOKS TO BE THE DRIEST DAY IN THE PERIOD, BUT WILL TURN UNSETTLED HEADING INTO FRIDAY NIGHT AND INTO THE WEEKEND OF INDEPENDENCE DAY AS THE NEXT IN THE PARADE OF SHORTWAVE TROUGHS DIGS INTO THE GREAT LAKES REGION. && .AVIATION /03Z MONDAY THROUGH FRIDAY/... THROUGH 00Z TUESDAY...A VARIETY OF FLIGHT CATEGORIES IS ANTICIPATED FOR TONIGHT...WITH A GRADUAL IMPROVEMENT TO VFR DURING THE DAY MONDAY. AREAS OF LOWER STRATUS CLOUDS...DRIZZLE...SOME POSSIBLE FOG/MIST...AND LINGERING RAIN SHOWERS WILL PERSIST THROUGH AT LEAST 12Z MONDAY MORNING...BEFORE CEILINGS GRADUALLY LIFT AND SHOWERS/DRIZZLE END. THIS WILL LEAD TO REDUCTIONS IN BOTH CEILINGS/VISIBILITIES AT TIMES. MOST IMPACTED WILL BE MSS/SLK/MPV WHERE MVFR AND PERIODS OF IFR ARE LIKELY. OTHERWISE VFR/MVFR AT BTV/PBG/RUT IS EXPECTED. MVFR CEILINGS LINGER THROUGH MONDAY MORNING BEFORE LIFTING TO VFR WITH BREAKS IN THE OVERCAST TOWARDS AND AFTER 18Z. WINDS LIGHT AND LOCALLY VARIABLE TONIGHT TURN GENERALLY WEST 3-7 KNOTS ON MONDAY. OUTLOOK 00Z TUESDAY THROUGH FRIDAY... LOOKING AT PREDOMINANTLY VFR ALTHOUGH THERE WILL BE MULTIPLE CHANCES FOR MVFR/IFR IN SCATTERED RAIN SHOWERS AND THUNDERSTORMS AS SEVERAL SYSTEMS TRAVERSE THE REGION. THESE CHANCES WILL BE HIGHEST TUESDAY AFTERNOON/EVENING AND WEDNESDAY AFTERNOON/EVENING. NOCTURNAL RADIATION FOG ALSO POSSIBLE MONDAY NIGHT...WEDNESDAY NIGHT...AND THURSDAY NIGHT WITH IFR/LIFR CONDITIONS...ESPECIALLY MPV/SLK. && .CLIMATE... AS OF 500 PM EDT SUNDAY...IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. ONE MONTHLY RECORD HAS ALREADY BEEN SET AT MONTPELIER AND WITH ADDITIONAL RAINFALL TONIGHT INTO TOMORROW, AND THE POTENTIAL FOR MORE RAIN ON TUESDAY, THE RECORDS AT BURLINGTON AND MOUNT MANSFIELD ARE IN JEOPARDY. AS OF 5 PM SUNDAY AFTERNOON, MONTPELIER HAS BROKEN ITS MONTHLY JUNE RAINFALL RECORD. AS OF 5 PM, 8.85 INCHES OF RAINFALL HAD FALLEN IN JUNE 2015 AT MONTPELIER. THE PRIOR RECORD WAS 8.36 INCHES SET IN 2013. A SUMMARY OF CURRENT RAINFALL TOTALS FOR BURLINGTON AND MT. MANSFIELD, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS AS OF 5 PM 06/28. AT 8.44 INCHES, BURLINGTON NEEDS 1.48 INCHES OF ADDITIONAL RAINFALL TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET IN 1922. AT 14.87 INCHES, MT. MANSFIELD NEEDS 0.41 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...KGM NEAR TERM...LAHIFF SHORT TERM...KGM LONG TERM...LOCONTO AVIATION...MUCCILLI CLIMATE...LOCONTO/MUCCILLI
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
340 PM EDT SAT JUN 27 2015 .SYNOPSIS... SURFACE LOW PRESSURE WILL BRING A WIDESPREAD RAINFALL TONIGHT THROUGH SUNDAY NIGHT, WITH SOME LINGERING SHOWERS POSSIBLE MONDAY MORNING. RAINFALL AMOUNTS OF ONE TO TWO INCHES WILL CAUSE RISES ON LOCAL WATERWAYS WITH SEVERAL RIVERS APPROACHING BANKFULL SUNDAY AND SUNDAY NIGHT. IN ADDITION, LOCALIZED GUSTY WINDS ARE LIKELY ALONG THE WESTERN SLOPES OF THE ADIRONDACKS AND GREEN MOUNTAINS SUNDAY MORNING, WITH BELOW NORMAL TEMPERATURES. DRIER CONDITIONS BRIEFLY RETURN FOR THE LATTER HALF OF MONDAY THROUGH EARLY TUESDAY MORNING. && .NEAR TERM /UNTIL 8 AM SUNDAY MORNING/... AS OF 340 PM EDT SATURDAY...FLOOD WATCH IN EFFECT FOR TONIGHT THROUGH SUNDAY NIGHT FOR EXCESSIVE RAINFALL... LIGHT RAINFALL WILL SPREAD NORTH AND EAST ACROSS THE NORTH COUNTRY TONIGHT AS A SURFACE LOW NEAR WESTERN LAKE ERIE BEGINS TO REDEVELOP NEAR THE SOUTHERN NJ COAST. A STRONG UPPER LEVEL JET STREAK WILL PROVIDE LIFT IN MOIST AIR. PWATS WILL RANGE FROM 1-1.5 INCHES OVERNIGHT WITH GREATEST PWATS LOCATED AREAS SOUTH AND EAST. AN ANONYMOUSLY STRONG SOUTHEASTERLY 850MB JET OF 35 TO 45 KNOTS MOVES IN FROM THE SOUTH MAINLY BETWEEN 03Z-09Z, INCREASING TO 50- 60KTS BETWEEN 09Z-21Z. MODEL ANOMALIES CONTINUE TO MAGNITUDE OF THIS JET IS 4 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR, MAINLY OVERNIGHT INTO SUNDAY MORNING. THIS WILL INFLUENCE RAINFALL DISTRIBUTION WITH OVERNIGHT RAINFALL TOTALS RANGING FROM 0.5-1.5 INCHES. HIGHEST AMOUNTS WILL BE ALONG THE EASTERN SLOPES OF THE GREEN MOUNTAINS AND ADIRONDACKS. THIS RAINFALL COMBINED WITH ALREADY SATURATED GROUND CONDITIONS WILL RESULT IN SIGNIFICANT RISES ON ALL STREAMS AND RIVERS. THE RAINFALL TONIGHT WILL BE THE HEAVIEST OF THIS EVENT. THE AFOREMENTIONED LOW LEVEL JET WILL PRODUCE THE POTENTIAL FOR SOME GUSTY TO LOCALLY STRONG DOWNSLOPE WINDS ACROSS THE FAVORED LOCATIONS ON THE WESTERN SLOPES OF THE GREEN MOUNTAINS OF VERMONT. HOWEVER, POTENTIAL MIXING IS QUESTIONABLE SINCE STRONGEST WINDS WILL OCCUR DURING STEADY RAINFALL. BUFKIT MODELS SHOW THE JET REMAINING ABOVE THE INVERSION. EXPECT SUMMITS TO EXPERIENCE STRONG GUSTY WINDS AND ISOLATED LOCALLY HIGH GUSTS OVERNIGHT. MIN TEMPERATURES WILL GENERALLY BE IN THE 50S WITH THE CLOUDS AND RAIN OVERNIGHT. && .SHORT TERM /8 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 340 PM EDT SATURDAY...FLOOD WATCH IN EFFECT FOR TONIGHT THROUGH SUNDAY NIGHT FOR EXCESSIVE RAINFALL... CLOUDY AND RAINY CONDITIONS CONTINUE SUNDAY MORNING WITH THE LOW LEVEL JET KEEPING SUMMITS BREEZY AND POSSIBLE ISOLATED STRONG WIND GUSTS. AS THE 500MB LOW PROGRESSES NORTHEASTWARD FROM LAKE ERIE AND THE SURFACE LOW TRAVELS OVER THE REGION, MODELS INDICATE POSSIBLE DRY SLOT WILL MOVE OVER THE NORTH COUNTRY FOR THE LATTER HALF OF THE DAY. THIS WILL GIVE A CHANCE FOR THE STRONG LOW LEVEL JET TO MIX DOWN IN AREAS THAT EXPERIENCE DRYING. BUT AS THE DRY SLOW MOVES NORTHWARD, SO DOES THE JET. THEREFORE EXPECT ISOLATED DOWNSLOPING STRONG WIND GUSTS, BUT NOTHING WIDESPREAD. SIGNIFICANTLY COOLER TEMPERATURES EXPECTED, MAXING OUT IN THE LOW TO MID 60S. AS THE 500MB LOW PUSHES INTO THE ST LAWRENCE VALLEY SUNDAY EVENING, MORE LIFT WILL ALLOW PRECIPITATION TO FILL IN THE DRY SLOT WITH AMBLE LOW LEVEL MOISTURE REMAINING. LINGERING RAIN SHOWERS FOR THE FIRST HALF OF MONDAY AS UPPER TROUGH STILL AFFECTS THE AREA UNDER CYCLONIC FLOW. RIDGING EXPECTED TO DRY THINGS OUT THE LATTER HALF OF MONDAY. EXPECT STORM TOTAL RAINFALLS THROUGH MONDAY MID DAY OF 1-2 INCHES WITH LOCALLY HIGHER AMOUNTS UP TO 2.3 INCHES ALONG THE EASTERN SLOPES. TEMPS BOTH SUNDAY AND MONDAY WILL RUN WELL BELOW NORMAL FOR LATE JUNE WITH HIGHS ONLY IN THE 50S AND 60S. MONDAY NIGHT WILL SEE SOME CLEARING IN DRIER CONDITIONS WITH MIN TEMPERATURES IN THE MID 4OS TO UPPER 50S. BEFORE MORE CLOUDS BEGIN TO ENCROACH UPON THE AREA FROM THE WEST. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 340 PM EDT SATURDAY...AMPLIFIED CONUS MID-TROPOSPHERIC PATTERN IN THE MEAN FOR THE EXTENDED, FEATURING LARGE-SCALE TROUGHING ACROSS EASTERN THIRD OF THE CONUS. GUIDANCE CONTINUES TO BENEFIT FROM GOOD CONSISTENCY REGARDING WHAT SHOULD BE A CONTINUATION OF THE UNSETTLED/WET PATTERN THE NORTH COUNTRY HAS BEEN MIRED IN JUNE INTO THE FIRST WEEK OF JULY. TEMPERATURES AT OR BELOW SEASONAL NORMALS - COOLER WITH RESPECT TO THE HIGHS. DAILY SPECIFICS TO FOLLOW... TUESDAY/WEDNESDAY: AN INITIALLY NEUTRALLY-TILTED SHORTWAVE TROUGH OVER GREAT LAKES REGION ASSUMES A NEGATIVELY TILT THIS PERIOD, AND ITS ACCOMPANYING SURFACE LOW PRODUCES SHOWERS AND POSSIBLE TUESDAY AFTERNOON/EVENING THUNDERSTORMS. GREATEST LIMITING FACTOR IN REGARD TO CONVECTIVE POTENTIAL IS IN TERMS OF THE DEGREE OF INSTABILITY, AS LOTS OF CLOUDS AND MARGINAL MID-LEVEL LAPSE RATES KEEPS INSTABILITY GENERALLY AT/BELOW 500 J/KG CAPE. HOWEVER, THIS MAY BE OFFSET SOMEWHAT BY FAVORABLE DYNAMIC ASCENT WITH NEGATIVELY TILTED TROUGH, AND THERE IS 35-40 KTS OF DEEP-LAYER (0-6 KM AGL) SHEAR PER GFS SOUNDINGS. PWATS DO INCREASE UP TO 1.25 INCHES SUPPORTING SOME LOCALLY HEAVIER DOWNPOURS. LOW MOVES UP INTO THE ST. LAWRENCE RIVER WITH TAPERING SHOWERS INTO WEDNESDAY. COULD SEE QPF AMOUNTS UP TO A HALF-INCH OUTSIDE OF ANY CONVECTION TUESDAY/WEDNESDAY. WEDNESDAY NIGHT: POST-FRONTAL COLD THERMAL ADVECTION AS 1000-500MB THICKNESS TROUGH BUILDS OVER NORTH COUNTRY. THOUGH CONDITIONS GENERALLY DRY LATE, CLEARING SKIES AND COOLING THERMAL PROFILES (+6 TO +8C) SUPPORTS LOWS IN THE UPPER 40S TO MID 50S. THURSDAY/FRIDAY: BRIEF RESPITE IN UNSETTLED PATTERN AS WEAK RIDGE BUILDS IN SFC AND ALOFT. SHOULD SEE MOSTLY CLEAR SKIES SUPPORTING HIGHS BACK INTO THE L/M70S THURSDAY AND M/U70S BY FRIDAY, THOUGH RATHER COOL LOWS THURSDAY NIGHT IN THE U40S TO M/U50S. THOUGH IT IS STILL EARLY TO PIN SPECIFIC DETAILS, A LOOK AT THE FOURTH OF JULY DOESN`T LOOK TOO FAVORABLE FOR FIREWORKS WATCHING, WITH INCREASING THREAT OF SHOWERS AHEAD OF NEXT SYSTEM LATER ON THE FOURTH. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...VFR BUT WITH A GENERAL LOWERING TREND IN CEILINGS THROUGH 00Z SUNDAY. GREATER AVIATION IMPACT ANTICIPATED AFTER 00Z SUNDAY, AS FLIGHT CATEGORIES DETERIORATE TO MVFR (PERIODS IFR CEILINGS) IN STEADY RAIN. PERIODS OF LOW-LEVEL WIND SHEAR AS WELL. VIS SATELLITE TRENDS DEPICT HIGH CLOUDS GRADUALLY LOWERING/THICKENING WITH TIME, TRENDS THAT WILL CONTINUE INTO THE EARLY EVENING. I`VE LARGELY USED RECENT HRRR AND BTV WRF OUTPUT TO TIME WARM- FRONTAL RAIN SHIELD EVIDENT OVER SOUTHERN NEW YORK STATE INTO OUR TAF AIRSPACE. MOST TAFS SHOULD SEE RAIN STEADILY INCREASING IN INTENSITY (3-6 SM) AFTER 02Z. BUFKIT RH PROGS SEEMS TO BE UNDER DOING CEILINGS, AS THERE ARE ALREADY SEVERAL OBSERVATIONS OF IFR/MVFR CEILINGS IN THE RAIN SHIELD. KEPT THIS LINE OF THINKING FOR CEILING FCST. LOW- LEVEL WIND FIELDS WILL BE INCREASING STEADILY (UP TO 45 KTS) AS RAIN DEVELOPS AND SUPPORT PERIODS OF LLWS. WINDS WILL TEND SOUTHEAST AROUND 10 KTS, EXCEPT 20 KNOTS WITH GUSTS TO 30 KTS AT RUT ONCE LOW- LEVEL FLOW INCREASES. WARM FRONTAL RAIN SHIELD AND ASSOCIATED LLWS LIFTS NORTHWARD BETWEEN 12-15Z. CONTINUED MVFR BEHIND IT THOUGH, AS DRY-SLOT LIFTS NORTH WITH A CHANGE FROM STEADY RAIN TO SPOTTY DRIZZLE/LIGHT RAIN. THOUGH GUSTY SOUTHEAST WINDS CONTINUE AT RUT, WINDS ELSEWHERE EASTERLY UNDER 10 KTS SUNDAY. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUNDAY-12Z MONDAY...MVFR/IFR TREND TO VFR/MVFR CLOSER TO 12Z MONDAY AS LOW PRESSURE AND ASSOCIATED SHOWERS LIFTS NORTHEAST. 12Z MONDAY-18Z TUESDAY...GENERALLY VFR WITH TAPERING VFR SHOWERS 12-18Z MONDAY. 18Z TUESDAY-12Z WEDNESDAY...VFR WITH INTERVALS OF MVFR/IFR LIKELY IN SHOWERS AND POSSIBLE THUNDERSTORMS. 12Z WEDNESDAY-00Z THURSDAY...UPPER TROUGH ACROSS THE REGION MAINTAINS CHANCES FOR RAIN SHOWERS AND PERIODS OF MVFR CONDITIONS. 00Z THURSDAY ONWARD...VFR AS HIGH PRESSURE BUILDS IN. POTENTIAL FOR EVENING LIFR FOG THURSDAY NIGHT. && .HYDROLOGY... AS OF 340 PM EDT SATURDAY...RAIN WILL SPREAD NORTHEASTWARD ACROSS THE NORTH COUNTRY THIS EVENING THROUGH MONDAY MORNING WITH TOTAL RAINFALL AMOUNTS RANGING FROM 1-2 INCHES AND LOCALLY OVER 2" ACROSS THE EASTERN SLOPES OF THE ADIRONDACKS AND SOUTHERN GREENS. THESE AMOUNTS WILL CAUSE SIGNIFICANT WATERSHED RISES, WITH SOME STREAMS AND RIVERS LIKELY APPROACHING BANKFULL OR MINOR FLOOD, ESPECIALLY ACROSS NORTHERN NEW YORK WHERE RIVER FLOWS AND WATER LEVELS CONTINUE TO RUN ABOVE NORMAL IN MANY SPOTS. PARTICULAR RIVERS OF INTEREST WILL BE THE EAST BRANCH OF THE AUSABLE RIVER, SARANAC RIVER AND BARTON RIVER WHICH ALL EXPERIENCED FLOODING RECENTLY. ALSO THE RAQUETTE RIVER AT PIERCEFIELD AND SOUTH COLTON WILL NEED TO BE WATCHED AS IT`S ALREADY RUNNING NEAR AND ABOVE ACTION STAGE AND IT WON`T TAKE MUCH TO PUSH IT OVER FLOOD STAGE. && .CLIMATE... IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. WITH ADDITIONAL RAINFALL TONIGHT INTO TOMORROW, AND THE POTENTIAL FOR MORE RAIN ON TUESDAY, MONTHLY JUNE RAINFALL RECORDS ARE IN JEOPARDY FOR SOME OF OUR CLIMATE SITES: BURLINGTON, MONTPELIER, AND MOUNT MANSFIELD. A SUMMARY OF CURRENT RAINFALL TOTALS FOR THESE SITES, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS CURRENT AS OF 6/26. AT 7.70 INCHES, BURLINGTON NEEDS 2.22 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET IN 1922. AT 7.45 INCHES, MONTPELIER NEEDS 0.91 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 8.36 INCHES SET IN 2013. AT 14.16 INCHES, MT. MANSFIELD NEEDS 1.12 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FLOOD WATCH FROM 2 AM EDT SUNDAY THROUGH MONDAY MORNING FOR VTZ002>012-016>019. NY...FLOOD WATCH FROM 2 AM EDT SUNDAY THROUGH MONDAY MORNING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...LAHIFF/KGM NEAR TERM...KGM SHORT TERM...KGM LONG TERM...LOCONTO AVIATION...LOCONTO HYDROLOGY...TEAM BTV CLIMATE...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
129 PM EDT SAT JUN 27 2015 .SYNOPSIS... DRY CONDITIONS ARE EXPECTED DURING THE DAYLIGHT HOURS TODAY UNDER FILTERED SUNSHINE, BEFORE A DEVELOPING AREA OF LOW PRESSURE PRODUCES A WIDESPREAD RAINFALL TONIGHT THROUGH SUNDAY NIGHT. RAINFALL AMOUNTS OF ONE TO TWO INCHES WILL CAUSE RISES ON LOCAL WATERWAYS WITH SEVERAL RIVERS APPROACHING BANKFULL SUNDAY. IN ADDITION, LOCALIZED GUSTY WINDS ARE LIKELY ALONG THE WESTERN SLOPES OF THE ADIRONDACKS AND GREEN MOUNTAINS SUNDAY MORNING, WITH BELOW NORMAL TEMPERATURES. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 128 PM EDT SATURDAY...UPSTREAM RAINFALL HAS GENERALLY BEEN LIGHT WITH SURFACE OBSERVATIONS REPORTING LIGHT RAIN AND 6 HR PRECIPITATION AMOUNTS OF A FEW HUNDREDTHS TO HALF AN INCH. THERE ARE SOME REPORTS IN CENTRAL PA BETWEEN 0.5-1 INCH. EXPECT LIGHT RAIN CURRENTLY AROUND SYRACUSE NY TO MOVE INTO THE ADIRONDACKS, ST LAWRENCE VALLEY AND SOUTHERN VERMONT BETWEEN 22Z-00Z. MAX TEMPERATURES EXPECTED TO REACH THE LOW TO MID 70S FOR MOST AREAS BEFORE RAIN MOVES IN. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... AS OF 445 AM EDT SATURDAY... FLOOD WATCH IN EFFECT FOR TONIGHT THROUGH SUNDAY NIGHT FOR EXCESSIVE RAINFALL... FORECAST REMAINS ON TRACK FOR A WET AND WINDY SECOND HALF OF THE WEEKEND AS A DEVELOPING LOW PRESSURE SYSTEM OVER THE OHIO RIVER VALLEY THIS MORNING TRACKS INTO THE EASTERN GREAT LAKES TONIGHT, AND ACROSS THE BTV CWA SUNDAY TO THE BAY OF FUNDY BY 12Z MONDAY. WIDESPREAD RAIN WILL DEVELOP ACROSS THE AREA TONIGHT THROUGH SUNDAY NIGHT AS AN ANOMALOUSLY STRONG SOUTHEASTERLY 850MB JET OF 50 TO 60 KNOTS ADVECTS PLENTY OF MOISTURE INTO THE REGION. I MENTION THE JET IS ANONYMOUSLY STRONG AS THE LATEST NAEFS GEFS CONTINUES TO SHOW ITS STRENGTH AND MAGNITUDE IS 4 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. THIS KIND OF LOW LEVEL JET IS SOMETHING WE SEE MORE IN A WINTER-TYPE STORM, NOT EARLY SUMMER! GIVEN THE STRONG LOW LEVEL WINDS, WE EXPECT RAINFALL TO BE HIGHLY INFLUENCED BY TOPOGRAPHY WITH BASIN AVERAGES BY 12Z MONDAY FROM 1-2" WITH LOCALIZED AREAS OVER 2" OVER PORTIONS OF THE EASTERN DACKS AND SOUTHERN GREENS WITH HEAVIEST AND RAINFALL OCCURRING FROM 02-16Z SUNDAY. THIS RAINFALL COMBINED WITH ALREADY SATURATED GROUND CONDITIONS WILL RESULT IN SIGNIFICANT RISES ON ALL STREAMS AND RIVERS. WITH THIS IN MIND WE`VE HOISTED A FLOOD WATCH FOR THE ENTIRE AREA EXCEPT IN THE CHAMPLAIN ISLANDS. SEE HYDRO SECTION BELOW FOR ADDITIONAL DETAILS. IN ADDITION TO THE HYDRO THREAT, THE AFOREMENTIONED LOW LEVEL JET WILL PRODUCE THE POTENTIAL FOR SOME GUSTY TO LOCALLY STRONG DOWNSLOPE WINDS ACROSS THE FAVORED LOCATIONS ON THE WESTERN SLOPES OF THE GREEN MOUNTAINS OF VERMONT. OUR TRUSTY LOCAL 4KM WRF CONTINUES TO SHOW A 925MB JET OF 45 TO 55 KNOTS FOCUSED ON EASTERN ADDISON AND RUTLAND COUNTIES AND TO A LESSER EXTENT EASTERN CHITTENDEN. BIG QUESTION CONTINUES TO BE HOW MUCH MIXING OCCURS, AS THE STRONGEST WINDS DEVELOP DURING THE PERIOD OF HEAVIEST RAINFALL. THE POTENTIAL FOR A LOW END WIND ADVISORY EXISTS ACROSS THESE ZONES, BUT DUE TO THE UNCERTAINTY OF MIXING CAP MAX GUSTS TO 45 MPH AND ALLOW THE NEXT SHIFT TO ASSESS THE 12Z MODEL SUITE. AS THE LOW SHIFTS FURTHER EAST INTO THE GULF OF ST. LAWRENCE MONDAY PRECIPITATION WILL TAPER OFF BUT STILL EXPECT TO SEE SOME SCATTERED SHOWERS AROUND AS AMPLE LOW LEVEL MOISTURE REMAINS AND WE REMAIN UNDER CYCLONIC NORTHWEST FLOW. TEMPS BOTH SUNDAY AND MONDAY WILL RUN WELL BELOW NORMAL FOR LATE JUNE WITH HIGHS ONLY IN THE 50S AND 60S. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 320 AM EDT SATURDAY...RELATIVELY ACTIVE WEATHER PATTERN WILL CONTINUE INTO THE LONG-TERM PERIOD WITH STRONG INTERMOUNTAIN WEST 500MB RIDGING CONTINUING TO SUPPORT MEAN TROUGH AXIS ACROSS THE GREAT LAKES AND OHIO VALLEY REGION. WEATHER IS BRIEFLY QUIET MONDAY NIGHT AHEAD OF DEEPENING TROUGH ACROSS THE GREAT LAKES REGION...BUT WILL SEE INCREASING CYCLONIC MID-LEVEL FLOW AND HEIGHT FALLS SHIFTING EWD INTO NY/NEW ENGLAND DURING THE DAY TUESDAY. THIS WILL RESULT IN INCREASING CHANCES FOR PRECIPITATION BY TUESDAY AFTERNOON. SOME POTENTIAL FOR AT LEAST WEAK SURFACE- BASED INSTABILITY AND INCREASING SFC-6KM SHEAR OF 30-40 KTS IN ADVANCE OF APPROACHING TROUGH AXIS. HAVE INCLUDED CHANCES FOR THUNDERSTORMS 18Z TUE THROUGH 03Z WED...AND WE/LL NEED TO MONITOR POTENTIAL MESOSCALE DETAILS FOR POTENTIAL STRONGER STORMS DEPENDING ON INSTABILITY FIELDS. GIVEN ANTECENDENT MOIST CONDITIONS...ADDITIONAL RAINFALL MAY ALSO ADD TO EXISTING HYDRO CONCERNS AND WILL NEED TO BE MONITORED LATE TUESDAY THRU TUESDAY NIGHT. 850MB TEMPS AND MOS GUIDANCE POINT TO HIGH TEMPERATURES ON TUESDAY IN THE MID-UPR 70S. BROAD UPPER TROUGH REMAINS IN PLACE TUESDAY NIGHT INTO WEDNESDAY WITH CONTINUED CHANCES FOR RAIN SHOWERS. CLOUDS SHOULD MITIGATE DIURNAL COOLING AND KEEP OVERNIGHT LOWS IN THE UPR 50S TO LOWER 60S FOR TUESDAY NIGHT. HIGHS WEDNESDAY GENERALLY LOW-MID 70S WITH CONSIDERABLE CLOUDINESS. KEPT POPS 40-60 PERCENT RANGE TUESDAY NIGHT THRU WEDNESDAY. IT APPEARS COLD FRONTAL PASSAGE AND DEVELOPING NW FLOW BEHIND MID-LEVEL TROUGH AXIS WILL USHER IN DRIER AIR AND SUBSIDENCE BY THURSDAY MORNING. 00Z GFS AND ECMWF TRENDING DRIER THU/FRIDAY WITH HIGHS REMAINING IN THE MID-UPR 70S. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...VFR BUT WITH A GENERAL LOWERING TREND IN CEILINGS THROUGH 00Z SUNDAY. GREATER AVIATION IMPACT ANTICIPATED AFTER 00Z SUNDAY, AS FLIGHT CATEGORIES DETERIORATE TO MVFR (PERIODS IFR CEILINGS) IN STEADY RAIN. PERIODS OF LOW-LEVEL WIND SHEAR AS WELL. VIS SATELLITE TRENDS DEPICT HIGH CLOUDS GRADUALLY LOWERING/THICKENING WITH TIME, TRENDS THAT WILL CONTINUE INTO THE EARLY EVENING. I`VE LARGELY USED RECENT HRRR AND BTV WRF OUTPUT TO TIME WARM- FRONTAL RAIN SHIELD EVIDENT OVER SOUTHERN NEW YORK STATE INTO OUR TAF AIRSPACE. MOST TAFS SHOULD SEE RAIN STEADILY INCREASING IN INTENSITY (3-6 SM) AFTER 02Z. BUFKIT RH PROGS SEEMS TO BE UNDERDOING CEILINGS, AS THERE ARE ALREADY SEVERAL OBSERVATIONS OF IFR/MVFR CEILINGS IN THE RAIN SHIELD. KEPT THIS LINE OF THINKING FOR CEILING FCST. LOW- LEVEL WIND FIELDS WILL BE INCREASING STEADILY (UP TO 45 KTS) AS RAIN DEVELOPS AND SUPPORT PERIODS OF LLWS. WINDS WILL TEND SOUTHEAST AROUND 10 KTS, EXCEPT 20 KNOTS WITH GUSTS TO 30 KTS AT RUT ONCE LOW- LEVEL FLOW INCREASES. WARM FRONTAL RAIN SHIELD AND ASSOCIATED LLWS LIFTS NORTHWARD BETWEEN 12-15Z. CONTINUED MVFR BEHIND IT THOUGH, AS DRY-SLOT LIFTS NORTH WITH A CHANGE FROM STEADY RAIN TO SPOTTY DRIZZLE/LIGHT RAIN. THOUGH GUSTY SOUTHEAST WINDS CONTINUE AT RUT, WINDS ELSEWHERE EASTERLY UNDER 10 KTS SUNDAY. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUNDAY-12Z MONDAY...MVFR/IFR TREND TO VFR/MVFR CLOSER TO 12Z MONDAY AS LOW PRESSURE AND ASSOCIATED SHOWERS LIFTS NORTHEAST. 12Z MONDAY-18Z TUESDAY...GENERALLY VFR WITH TAPERING VFR SHOWERS 12-18Z MONDAY. 18Z TUESDAY-12Z WEDNESDAY...VFR WITH INTERVALS OF MVFR/IFR LIKELY IN SHOWERS AND POSSIBLE THUNDERSTORMS. 12Z WEDNESDAY-00Z THURSDAY...UPPER TROUGH ACROSS THE REGION MAINTAINS CHANCES FOR RAIN SHOWERS AND PERIODS OF MVFR CONDITIONS. 00Z THURSDAY ONWARD...VFR AS HIGH PRESSURE BUILDS IN. POTENTIAL FOR EVENING LIFR FOG THURSDAY NIGHT. && .HYDROLOGY... AS OF 445 AM EDT SATURDAY...A WIDESPREAD RAIN EVENT WILL OCCUR THIS EVENING THROUGH SUNDAY NIGHT ACROSS OUR HYDRO SERVICE AREA. TOTAL RAINFALL AMOUNTS WILL BE HIGHLY INFLUENCED BY TERRAIN, WITH MODEL CONSENSUS VALUES RANGING FROM 1-2" AREA-WIDE TO LOCALLY OVER 2" ACROSS THE EASTERN SLOPES OF THE ADIRONDACKS AND SOUTHERN GREENS. THESE AMOUNTS WILL LIKELY CAUSE SIGNIFICANT WATERSHED RISES, WITH SOME STREAMS AND RIVERS LIKELY APPROACHING BANKFULL OR MINOR FLOOD, ESPECIALLY ACROSS NORTHERN NEW YORK WHERE RIVER FLOWS AND WATER LEVELS CONTINUE TO RUN ABOVE NORMAL IN MANY SPOTS. PARTICULAR RIVERS OF INTEREST WILL BE THE EAST BRANCH OF THE AUSABLE RIVER, SARANAC RIVER AND BARTON RIVER WHICH ALL EXPERIENCED FLOODING RECENTLY. ALSO THE RAQUETTE RIVER AT PIERCEFIELD AND SOUTH COLTON WILL NEED TO BE WATCHED AS IT`S ALREADY RUNNING NEAR AND ABOVE ACTION STAGE AND IT WON`T TAKE MUCH TO PUSH IT OVER FLOOD STAGE. && .CLIMATE... IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. WITH ADDITIONAL RAINFALL TONIGHT INTO TOMORROW, AND THE POTENTIAL FOR MORE RAIN ON TUESDAY, MONTHLY JUNE RAINFALL RECORDS ARE IN JEOPARDY FOR SOME OF OUR CLIMATE SITES: BURLINGTON, MONTPELIER, AND MOUNT MANSFIELD. A SUMMARY OF CURRENT RAINFALL TOTALS FOR THESE SITES, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS CURRENT AS OF 6/26. AT 7.70 INCHES, BURLINGTON NEEDS 2.22 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET IN 1922. AT 7.45 INCHES, MONTPELIER NEEDS 0.91 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 8.36 INCHES SET IN 2013. AT 14.16 INCHES, MT. MANSFIELD NEEDS 1.12 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FLOOD WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR VTZ002>012-016>019. NY...FLOOD WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...LAHIFF NEAR TERM...KGM SHORT TERM...LAHIFF LONG TERM...BANACOS AVIATION...LOCONTO HYDROLOGY...TEAM BTV CLIMATE...LOCONTO
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
121 PM EDT SAT JUN 27 2015 .SYNOPSIS... DRY CONDITIONS ARE EXPECTED DURING THE DAYLIGHT HOURS TODAY UNDER FILTERED SUNSHINE, BEFORE A DEVELOPING AREA OF LOW PRESSURE PRODUCES A WIDESPREAD RAINFALL TONIGHT THROUGH SUNDAY NIGHT. RAINFALL AMOUNTS OF ONE TO TWO INCHES WILL CAUSE RISES ON LOCAL WATERWAYS WITH SEVERAL RIVERS APPROACHING BANKFULL SUNDAY. IN ADDITION, LOCALIZED GUSTY WINDS ARE LIKELY ALONG THE WESTERN SLOPES OF THE ADIRONDACKS AND GREEN MOUNTAINS SUNDAY MORNING, WITH BELOW NORMAL TEMPERATURES. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1042 AM EDT SATURDAY...PLENTIFUL SUNSHINE WILL CONTINUE TO GIVE WAY TO INCREASING AND THICKENING CLOUDS AHEAD OF LOW PRESSURE. TEMPERATURES ALREADY REACHING THE UPPER 60S TO LOW 70S AND ARE EXPECTED TO WARM ANOTHER 5 DEGREES. PRECIP ASSOCIATED WITH THE APPROACHING SYSTEM LOOKS TO ARRIVE DURING THE LATE AFTERNOON ACROSS NORTHERN NEW YORK AND EVENING ACROSS VERMONT. FOR MORE ON THIS READ THE SHORT TERM SECTION BELOW. && .SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/... AS OF 445 AM EDT SATURDAY... FLOOD WATCH IN EFFECT FOR TONIGHT THROUGH SUNDAY NIGHT FOR EXCESSIVE RAINFALL... FORECAST REMAINS ON TRACK FOR A WET AND WINDY SECOND HALF OF THE WEEKEND AS A DEVELOPING LOW PRESSURE SYSTEM OVER THE OHIO RIVER VALLEY THIS MORNING TRACKS INTO THE EASTERN GREAT LAKES TONIGHT, AND ACROSS THE BTV CWA SUNDAY TO THE BAY OF FUNDY BY 12Z MONDAY. WIDESPREAD RAIN WILL DEVELOP ACROSS THE AREA TONIGHT THROUGH SUNDAY NIGHT AS AN ANOMALOUSLY STRONG SOUTHEASTERLY 850MB JET OF 50 TO 60 KNOTS ADVECTS PLENTY OF MOISTURE INTO THE REGION. I MENTION THE JET IS ANONYMOUSLY STRONG AS THE LATEST NAEFS GEFS CONTINUES TO SHOW ITS STRENGTH AND MAGNITUDE IS 4 STANDARD DEVIATIONS ABOVE NORMAL FOR THIS TIME OF YEAR. THIS KIND OF LOW LEVEL JET IS SOMETHING WE SEE MORE IN A WINTER-TYPE STORM, NOT EARLY SUMMER! GIVEN THE STRONG LOW LEVEL WINDS, WE EXPECT RAINFALL TO BE HIGHLY INFLUENCED BY TOPOGRAPHY WITH BASIN AVERAGES BY 12Z MONDAY FROM 1-2" WITH LOCALIZED AREAS OVER 2" OVER PORTIONS OF THE EASTERN DACKS AND SOUTHERN GREENS WITH HEAVIEST AND RAINFALL OCCURRING FROM 02-16Z SUNDAY. THIS RAINFALL COMBINED WITH ALREADY SATURATED GROUND CONDITIONS WILL RESULT IN SIGNIFICANT RISES ON ALL STREAMS AND RIVERS. WITH THIS IN MIND WE`VE HOISTED A FLOOD WATCH FOR THE ENTIRE AREA EXCEPT IN THE CHAMPLAIN ISLANDS. SEE HYDRO SECTION BELOW FOR ADDITIONAL DETAILS. IN ADDITION TO THE HYDRO THREAT, THE AFOREMENTIONED LOW LEVEL JET WILL PRODUCE THE POTENTIAL FOR SOME GUSTY TO LOCALLY STRONG DOWNSLOPE WINDS ACROSS THE FAVORED LOCATIONS ON THE WESTERN SLOPES OF THE GREEN MOUNTAINS OF VERMONT. OUR TRUSTY LOCAL 4KM WRF CONTINUES TO SHOW A 925MB JET OF 45 TO 55 KNOTS FOCUSED ON EASTERN ADDISON AND RUTLAND COUNTIES AND TO A LESSER EXTENT EASTERN CHITTENDEN. BIG QUESTION CONTINUES TO BE HOW MUCH MIXING OCCURS, AS THE STRONGEST WINDS DEVELOP DURING THE PERIOD OF HEAVIEST RAINFALL. THE POTENTIAL FOR A LOW END WIND ADVISORY EXISTS ACROSS THESE ZONES, BUT DUE TO THE UNCERTAINTY OF MIXING CAP MAX GUSTS TO 45 MPH AND ALLOW THE NEXT SHIFT TO ASSESS THE 12Z MODEL SUITE. AS THE LOW SHIFTS FURTHER EAST INTO THE GULF OF ST. LAWRENCE MONDAY PRECIPITATION WILL TAPER OFF BUT STILL EXPECT TO SEE SOME SCATTERED SHOWERS AROUND AS AMPLE LOW LEVEL MOISTURE REMAINS AND WE REMAIN UNDER CYCLONIC NORTHWEST FLOW. TEMPS BOTH SUNDAY AND MONDAY WILL RUN WELL BELOW NORMAL FOR LATE JUNE WITH HIGHS ONLY IN THE 50S AND 60S. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... AS OF 320 AM EDT SATURDAY...RELATIVELY ACTIVE WEATHER PATTERN WILL CONTINUE INTO THE LONG-TERM PERIOD WITH STRONG INTERMOUNTAIN WEST 500MB RIDGING CONTINUING TO SUPPORT MEAN TROUGH AXIS ACROSS THE GREAT LAKES AND OHIO VALLEY REGION. WEATHER IS BRIEFLY QUIET MONDAY NIGHT AHEAD OF DEEPENING TROUGH ACROSS THE GREAT LAKES REGION...BUT WILL SEE INCREASING CYCLONIC MID-LEVEL FLOW AND HEIGHT FALLS SHIFTING EWD INTO NY/NEW ENGLAND DURING THE DAY TUESDAY. THIS WILL RESULT IN INCREASING CHANCES FOR PRECIPITATION BY TUESDAY AFTERNOON. SOME POTENTIAL FOR AT LEAST WEAK SURFACE- BASED INSTABILITY AND INCREASING SFC-6KM SHEAR OF 30-40 KTS IN ADVANCE OF APPROACHING TROUGH AXIS. HAVE INCLUDED CHANCES FOR THUNDERSTORMS 18Z TUE THROUGH 03Z WED...AND WE/LL NEED TO MONITOR POTENTIAL MESOSCALE DETAILS FOR POTENTIAL STRONGER STORMS DEPENDING ON INSTABILITY FIELDS. GIVEN ANTECENDENT MOIST CONDITIONS...ADDITIONAL RAINFALL MAY ALSO ADD TO EXISTING HYDRO CONCERNS AND WILL NEED TO BE MONITORED LATE TUESDAY THRU TUESDAY NIGHT. 850MB TEMPS AND MOS GUIDANCE POINT TO HIGH TEMPERATURES ON TUESDAY IN THE MID-UPR 70S. BROAD UPPER TROUGH REMAINS IN PLACE TUESDAY NIGHT INTO WEDNESDAY WITH CONTINUED CHANCES FOR RAIN SHOWERS. CLOUDS SHOULD MITIGATE DIURNAL COOLING AND KEEP OVERNIGHT LOWS IN THE UPR 50S TO LOWER 60S FOR TUESDAY NIGHT. HIGHS WEDNESDAY GENERALLY LOW-MID 70S WITH CONSIDERABLE CLOUDINESS. KEPT POPS 40-60 PERCENT RANGE TUESDAY NIGHT THRU WEDNESDAY. IT APPEARS COLD FRONTAL PASSAGE AND DEVELOPING NW FLOW BEHIND MID-LEVEL TROUGH AXIS WILL USHER IN DRIER AIR AND SUBSIDENCE BY THURSDAY MORNING. 00Z GFS AND ECMWF TRENDING DRIER THU/FRIDAY WITH HIGHS REMAINING IN THE MID-UPR 70S. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... THROUGH 18Z SUNDAY...VFR BUT WITH A GENERAL LOWERING TREND IN CEILINGS THROUGH 00Z SUNDAY. GREATER AVIATION IMPACT ANTICIPATED AFTER 00Z SUNDAY, AS FLIGHT CATEGORIES DETERIORATE TO MVFR (PERIODS IFR CEILINGS) IN STEADY RAIN. PERIODS OF LOW-LEVEL WIND SHEAR AS WELL. VIS SATELLITE TRENDS DEPICT HIGH CLOUDS GRADUALLY LOWERING/THICKENING WITH TIME, TRENDS THAT WILL CONTINUE INTO THE EARLY EVENING. I`VE LARGELY USED RECENT HRRR AND BTV WRF OUTPUT TO TIME WARM- FRONTAL RAIN SHIELD EVIDENT OVER SOUTHERN NEW YORK STATE INTO OUR TAF AIRSPACE. MOST TAFS SHOULD SEE RAIN STEADILY INCREASING IN INTENSITY (3-6 SM) AFTER 02Z. BUFKIT RH PROGS SEEMS TO BE UNDERDOING CEILINGS, AS THERE ARE ALREADY SEVERAL OBSERVATIONS OF IFR/MVFR CEILINGS IN THE RAIN SHIELD. KEPT THIS LINE OF THINKING FOR CEILING FCST. LOW- LEVEL WIND FIELDS WILL BE INCREASING STEADILY (UP TO 45 KTS) AS RAIN DEVELOPS AND SUPPORT PERIODS OF LLWS. WINDS WILL TEND SOUTHEAST AROUND 10 KTS, EXCEPT 20 KNOTS WITH GUSTS TO 30 KTS AT RUT ONCE LOW- LEVEL FLOW INCREASES. WARM FRONTAL RAIN SHIELD AND ASSOCIATED LLWS LIFTS NORTHWARD BETWEEN 12-15Z. CONTINUED MVFR BEHIND IT THOUGH, AS DRY-SLOT LIFTS NORTH WITH A CHANGE FROM STEADY RAIN TO SPOTTY DRIZZLE/LIGHT RAIN. THOUGH GUSTY SOUTHEAST WINDS CONTINUE AT RUT, WINDS ELSEWHERE EASTERLY UNDER 10 KTS SUNDAY. OUTLOOK 18Z SUNDAY THROUGH THURSDAY... 18Z SUNDAY-12Z MONDAY...MVFR/IFR TREND TO VFR/MVFR CLOSER TO 12Z MONDAY AS LOW PRESSURE AND ASSOCIATED SHOWERS LIFTS NORTHEAST. 12Z MONDAY-18Z TUESDAY...GENERALLY VFR WITH TAPERING VFR SHOWERS 12-18Z MONDAY. 18Z TUESDAY-12Z WEDNESDAY...VFR WITH INTERVALS OF MVFR/IFR LIKELY IN SHOWERS AND POSSIBLE THUNDERSTORMS. 12Z WEDNESDAY-00Z THURSDAY...UPPER TROUGH ACROSS THE REGION MAINTAINS CHANCES FOR RAIN SHOWERS AND PERIODS OF MVFR CONDITIONS. 00Z THURSDAY ONWARD...VFR AS HIGH PRESSURE BUILDS IN. POTENTIAL FOR EVENING LIFR FOG THURSDAY NIGHT. && .HYDROLOGY... AS OF 445 AM EDT SATURDAY...A WIDESPREAD RAIN EVENT WILL OCCUR THIS EVENING THROUGH SUNDAY NIGHT ACROSS OUR HYDRO SERVICE AREA. TOTAL RAINFALL AMOUNTS WILL BE HIGHLY INFLUENCED BY TERRAIN, WITH MODEL CONSENSUS VALUES RANGING FROM 1-2" AREA-WIDE TO LOCALLY OVER 2" ACROSS THE EASTERN SLOPES OF THE ADIRONDACKS AND SOUTHERN GREENS. THESE AMOUNTS WILL LIKELY CAUSE SIGNIFICANT WATERSHED RISES, WITH SOME STREAMS AND RIVERS LIKELY APPROACHING BANKFULL OR MINOR FLOOD, ESPECIALLY ACROSS NORTHERN NEW YORK WHERE RIVER FLOWS AND WATER LEVELS CONTINUE TO RUN ABOVE NORMAL IN MANY SPOTS. PARTICULAR RIVERS OF INTEREST WILL BE THE EAST BRANCH OF THE AUSABLE RIVER, SARANAC RIVER AND BARTON RIVER WHICH ALL EXPERIENCED FLOODING RECENTLY. ALSO THE RAQUETTE RIVER AT PIERCEFIELD AND SOUTH COLTON WILL NEED TO BE WATCHED AS IT`S ALREADY RUNNING NEAR AND ABOVE ACTION STAGE AND IT WON`T TAKE MUCH TO PUSH IT OVER FLOOD STAGE. && .CLIMATE... IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. WITH ADDITIONAL RAINFALL TONIGHT INTO TOMORROW, AND THE POTENTIAL FOR MORE RAIN ON TUESDAY, MONTHLY JUNE RAINFALL RECORDS ARE IN JEOPARDY FOR SOME OF OUR CLIMATE SITES: BURLINGTON, MONTPELIER, AND MOUNT MANSFIELD. A SUMMARY OF CURRENT RAINFALL TOTALS FOR THESE SITES, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS CURRENT AS OF 6/26. AT 7.70 INCHES, BURLINGTON NEEDS 2.22 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET IN 1922. AT 7.45 INCHES, MONTPELIER NEEDS 0.91 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 8.36 INCHES SET IN 2013. AT 14.16 INCHES, MT. MANSFIELD NEEDS 1.12 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...FLOOD WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR VTZ002>012-016>019. NY...FLOOD WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR NYZ026>031-034-035-087. && $$ SYNOPSIS...LAHIFF NEAR TERM...LAHIFF/KGM SHORT TERM...LAHIFF LONG TERM...BANACOS AVIATION...LOCONTO HYDROLOGY...TEAM BTV CLIMATE...LOCONTO
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
326 PM EDT SAT JUN 27 2015 .SYNOPSIS... ONE MORE HUMID DAY TODAY BEFORE A COLD FRONT BRINGS DRIER AIR INTO THE REGION ON SUNDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT AHEAD OF THE COLD FRONT. THE FRONT WILL STALL NEAR THE COAST SUNDAY BEFORE DISSIPATING OFFSHORE MONDAY. REDEVELOPMENT OF BERMUDA HIGH PRESSURE MID THROUGH LATE WEEK WILL BRING HUMID CONDITIONS WITH LATE DAY THUNDERSTORMS. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... AS OF 330 PM SATURDAY...SCATTERED TSTMS ONGOING AND TRACKING ENE ACROSS THE AREA THIS AFTERNOON ASSOCIATED MAINLY WITH REMNANT MCV CIRCULATIONS AND SEA BREEZE CONVERGENCE INTERACTIONS. THE SEA-BREEZE INTERACTIONS MAY HELP SPIKE LOW-LEVEL HELICITY AND A SPIN-UP MESO OR FUNNEL CLOUD ALONG THE SEA BREEZE CANNOT BE RULED OUT. MOST RECENT SATELLITE-DERIVED PRECIPITABLE WATER ANIMATIONS SHOW A SWATH OF PWATS IN EXCESS OF 2 INCHES STREWN ACROSS THE CAROLINAS AND SOUTHERN GEORGIA. DEEPER CONVECTION REMAINS POSSIBLE THIS EVENING AS UPPER SUPPORT STRENGTHENS AND THIS REMAINS FAVORED ALONG AND WEST OF I-95. MODELS SHOW AS UPPER WINDS PARALLEL THE FRONT...CONVECTION MAY WEAKEN AS IT NEARS THE COAST OVERNIGHT INTO EARLY SUNDAY...ALTHOUGH RAIN CHANCES WILL CONTINUE INTO SUNDAY MORNING. THE PRIMARY THREAT REMAIN DAMAGING WINDS...AND AS THE UPPER TROUGH NEARS...LOW AND MID- LEVEL WINDS WILL INCREASE TO 30-40 KT. THUS ANY STORMS THAT ARE MAINTAINED TONIGHT WILL HAVE A SWIFT FORWARD MOTION. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 330 PM SATURDAY...THE MID LEVEL LOW WILL BE SITTING ACROSS THE EASTERN GREAT LAKES AT THE BEGINNING OF THE PERIOD WITH A BROAD SOUTHWEST FLOW ALOFT ACROSS THE EAST COAST. THE COLD FRONT WILL BE NEARSHORE WITH A WESTERLY FLOW IN ITS WAKE AND SOUTHWEST WINDS ACROSS THE WATERS. AS THE UPPER LEVEL JET (200MB) INTENSIFIES THE PUSH FOR THE FRONT BECOMES NON EXISTENT. I HAVE INCREASED POPS ALONG THE COAST FOR SUNDAY AS THE INLAND AREAS SHOULD REMAIN DRY. THE NAM IS SHOWING MORE ACTIVITY ALONG THE FRONT SUNDAY NIGHT WHILE THE GFS HAS A WEAKER SIGNAL. WILL WAIT FOR MORE CERTAINTY BEFORE ADDING POPS FOR THIS PERIOD BUT I DID INCREASE CLOUD COVER. ALL GUIDANCE SHOWS A WONDERFUL DAY MONDAY WITH LOWER DEWPOINTS...POSSIBLY INTO THE UPPER 50S INLAND MIXING DOWN AT MAX HEATING. CERTAINLY THE RELATIVE HUMIDITY WILL BE CONSIDERABLY LOWER ACROSS THE BOARD. OVERALL I TWEAKED TEMPERATURES ONLY SLIGHTLY. THE HIGHLIGHTS INCLUDE MOST IF NOT ALL AREAS BELOW 90 SUNDAY AND LOWS IN THE 60S INLAND. IT LOOKS LIKE THE COASTAL AREAS WONT BREAK THE 70 DEGREE MARK FOR LOWS. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 828 AM SATURDAY...CONSENSUS AMONG THE GLOBAL MEMBERS AND ENSEMBLE PLOTS DEPICT LOW AMPLITUDE BUT PERSISTENT UPPER TROUGHING ACROSS THE EASTERN CONUS TUESDAY THROUGH FRIDAY. CONFIGURATION WILL SUPPORT A STORM TRACK NEAR TO JUST NORTH OF THE AREA THAT MAY FOSTER IMPACTS FROM CONVECTIVE COMPLEXES...WHILE AIDING IN SURFACE TROUGHING INLAND AS A FOCUS FOR CONVECTIVE INITIATION IN DURING DIURNAL WARMING. SEVERAL SHORT-WAVES EMBEDDED IN THE TROUGHING WILL PROVIDE A DAILY CHANCE OF THUNDERSTORMS. COLUMN MOISTURE WILL BE INCREASING BEGINNING WEDNESDAY AS SUBSIDENCE ALOFT WANES. THE LOW-LEVEL WSW FLOW WILL LIKELY BRING MAXIMUM TEMPERATURES IN THE PERIOD NEAR TO SLIGHTLY ABOVE LATE JUNE/EARLY JULY STANDARDS. && .AVIATION /19Z SATURDAY THROUGH THURSDAY/... AS OF 18Z...FIRST WAVE OF CONVECTION MOVING THROUGH THE REGION WITH A BIT OF A LULL EXPECTED LATER THIS AFTERNOON. HIGH PWATS WILL GIVE US BRIEF PERIODS OF IFR VISIBILITIES IN THE HEAVIEST CONVECTION. STRONG SOUTHWEST FLOW WILL CONTINUE INTO THE EVENING HOURS. THE FRONT APPROACHES FROM THE WEST TONIGHT. THE HRRR MODEL DOES NOT HAVE THAT MUCH CONVECTION ALONG AND AHEAD OF THE FRONT...BUT THINK THINGS WILL BE FAIRLY ACTIVE OVERNIGHT. THE NAM STALLS THE FRONT ALONG THE COAST ON SUNDAY...BUT THINK WE WILL GET ENOUGH OF A WESTERLY WIND BY MID TO LATE MORNING TO KEEP CONVECTION EAST OF THE COASTAL TERMINALS...CERTAINLY WEST OF THE INLAND TERMINALS. EXTENDED OUTLOOK...VFR THROUGH TUESDAY. POSSIBLE AFTERNOON SHOWERS AND STORMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 330 PM SATURDAY...ADVISORY FLAGS ARE FLAPPING FOR SW 15-25 KT WINDS AND GUSTS TO 30 KT TONIGHT. ANY TSTMS OVER THE WATERS WILL BE CAPABLE OF 50 KT GUSTS AND MARINERS ARE ENCOURAGED TO OBTAIN RADAR UPDATES BEFORE HEADING OUT. OUTSIDE OF TSTMS SEAS 4-7 FEET OVERNIGHT AND HIGHEST OFFSHORE...AND SE OF CAPE FEAR. SEAS COMPOSED OF SW WAVES 4-5 FEET EVERY 6 SECONDS AND ESE WAVES 1-2 FEET IN 8-9 SECONDS INTERVALS. IN AND NEAR TSTMS A HEAVY CHOP WOULD QUICKLY DEVELOP ON THE WATERS. SW-W WINDS EARLY SUNDAY EXPECTED 10-20 KT AS THE FRONT STALLS ALONG THE COAST. SHORT TERM /SUNDAY THROUGH MONDAY/... AS OF 330 PM SATURDAY...COLD FRONT WILL NEVER REALLY MAKE IT ACROSS THE WATERS AS A SOUTHWEST FLOW WILL CONTINUE THROUGH ESSENTIALLY THE ENTIRE PERIOD. STRONGEST WINDS WILL OCCUR EARLY ON THE ORDER OF 15- 20 KNOTS. BY MIDDAY SUNDAY THE WINDS BEGIN A LONG DECENT DOWN TO TEN KNOTS OR LESS BY MONDAY MORNING. THE WINDS WILL INCREASE AGAIN MONDAY NIGHT DUE TO ENHANCED LOW LEVEL JETTING. THE SMALL CRAFT ADVISORY WILL CONTINUE THROUGH NOON SUNDAY AS RESIDUAL HIGHER SEAS PERSIST. BY MONDAY THE SEAS WILL BE DOWN TO 2-4 FEET. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 828 AM SATURDAY...MODERATE SW WINDS PREVAIL THIS PERIOD AS INLAND SURFACE TROUGHING INTERACTS WITH HIGH PRESSURE OFFSHORE YIELDING SW 10-20 KT FLOW. TSTMS MAY IMPACT INSHORE WATERS IN THE LATE AFTERNOONS THROUGH THE OVERNIGHT PERIODS. SEAS MAINLY 3-4 FT BUT UP TO 5 FT OFFSHORE AT TIMES...AS INLAND TROUGHING SHARPENS INTO MID-WEEK. SPECTRAL DATA SUGGEST SEAS WILL BE COMPRISED OF 3 FOOT WAVES FROM THE SSW EVERY 6 SECONDS...AND 1-2 FOOT WAVES FROM THE ESE EVERY 7-9 SECONDS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT SUNDAY FOR AMZ250-252-254- 256. && $$ SYNOPSIS...SHK NEAR TERM...MJC SHORT TERM...SHK LONG TERM...MJC AVIATION...DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
124 PM EDT SAT JUN 27 2015 .SYNOPSIS... ONE MORE HUMID DAY TODAY BEFORE A COLD FRONT BRINGS DRIER AIR INTO THE REGION ON SUNDAY. STRONG TO SEVERE THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND TONIGHT AHEAD OF THE COLD FRONT. THE FRONT WILL STALL NEAR THE COAST SUNDAY BEFORE DISSIPATING OFFSHORE MONDAY. REDEVELOPMENT OF BERMUDA HIGH PRESSURE MID THROUGH LATE WEEK WILL BRING HUMID CONDITIONS WITH LATE DAY THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 948 AM SATURDAY...UPSTREAM MCV GROUPINGS WERE SETTING OFF SCATTERED MORNING SHOWERS ACROSS SOUTH CAROLINA WESTWARD INTO EAST GEORGIA. LOW-ANGLE EARLY MORNING SUNLIGHT SHOWS WELL THE EMBEDDED CUMULUS TOWERS ASSOCIATED WITH THE IMPULSES. VAPOR CHANNEL SHOWS THESE PERTURBATIONS ARE NOW GETTING PICKED UP BY INCREASING SW SHEAR. OFF-SETTING THIS FACTOR HOWEVER IS DISPLAYED WELL IN VSBL ANIMATIONS THE POCKETS OF EARLY SUN WARMING THE GROUND. THE MCV FAMILY WILL BRING AN UPTICK IN POP VALUES INTO MIDDAY...AS THE FIRST SWIRL TRAVERSES MID TO LATE MORNING...THEN ANOTHER ON THE HEELS EARLY AFTERNOON. ALTHOUGH UPPER SUPPORT IS FADING WITH THE PERTURBATIONS...INTERACTION WITH THE SEA BREEZE BOUNDARY MAY ALLOW SHOWERS AND STORMS FILL IN ALONG IT. THE PRIMARY SEVERE WEATHER THREAT REMAINS TIED TO THE LINE OF STORMS EXPECTED TO DEVELOP ALONG AND AHEAD OF A COLD FRONT THIS EVENING...WHERE AN SPC ENHANCED RISK IS POSTED FOR THE PRIMARY THREAT OF DAMAGING WINDS. WINDS ALOFT NEARLY PARALLEL THE FRONTAL BOUNDARY OVERNIGHT WHICH SLOWS THE EASTWARD PROGRESSION OF THE FRONT...ALLOWING SHOWERS AND A FEW STORMS TO LINGER INTO EARLY SUNDAY OVER THE COASTAL INTERIOR TO THE BEACHES...CLEARING TO SEA THROUGH AFTERNOON. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 AM SATURDAY...ANOMALOUSLY STRONG SPRING-LIKE COLD FRONT TO CROSS THE AREA SUNDAY...BUT THE TRUE AIRMASS CHANGE NOW...UNFORTUNATELY...LOOKS SLOWER AND LESS IMPRESSIVE THAN PREVIOUSLY THOUGHT. COLD FRONT WILL DRAG ACROSS THE AREA DURING EARLY SUNDAY AS A LARGE TROUGH DIVES ACROSS THE EASTERN CONUS. HOWEVER...THIS FRONT IS NOW PROGGED TO STALL ALONG OR JUST OFF THE COAST...TYPICAL FOR LATE JUNE...AND WILL NOT REALLY PUSH AWAY AND WASH OUT UNTIL A SECONDARY VORT SWINGS THROUGH SUNDAY NIGHT INTO MONDAY. THIS WILL KEEP CLOUDS/SHOWER CHANCES ALONG THE COAST THROUGH SUNDAY...WITH SHOWERS/CLOUDS POSSIBLY INCREASING BACK TO THE WEST LATE IN THE DAY AS THE SECONDARY VORT TRIES TO SPAWN WEAK LOW PRESSURE ALONG THE BOUNDARY. THIS IS DEPICTED BY THE LATEST WPC GRAPHICS...AND WOULD SUGGEST SUNDAY WILL REMAIN HUMID...ESPECIALLY ACROSS THE EASTERN HALF OF THE CWA. WILL SHOW A SLIGHT INCREASE IN POP AND TEMP BEFORE DRYING THINGS OUT FOR MONDAY...ALTHOUGH WITH THE TROUGH AXIS REMAINING TO OUR WEST MID-LEVEL FLOW STAYS W/SW AND EVEN MONDAY WILL NOT BE AS COOL AND DRY AS PREVIOUSLY ANTICIPATED. HOWEVER...SHOWER ACTIVITY IS NOT EXPECTED ON MONDAY. TEMPS SUNDAY WILL BE IN THE MID 80S NEAR THE COAST...TO THE UPR 80S WELL INLAND. EXPECT HIGHS TO BE 1-3 DEGREES WARMER ON MONDAY AS THE FRONT WASHES OUT OFFSHORE WITHOUT ANY SIGNIFICANT COOL ADVECTION...ALTHOUGH DEW POINT TEMPERATURES WILL LIKELY BE ABOUT 5- 10 DEGREES COOLER THAN THEY HAVE RECENTLY BEEN. THIS WILL ALLOW MINS SUNDAY NIGHT TO DROP INTO THE 65-70 DEGREE RANGE...THEN SLIGHTLY WARMER MONDAY NIGHT AS SOUTHERLY FLOW QUICKLY RETURNS. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 828 AM SATURDAY...CONSENSUS AMONG THE GLOBAL MEMBERS AND ENSEMBLE PLOTS DEPICT LOW AMPLITUDE BUT PERSISTENT UPPER TROUGHING ACROSS THE EASTERN CONUS TUESDAY THROUGH FRIDAY. CONFIGURATION WILL SUPPORT A STORM TRACK NEAR TO JUST NORTH OF THE AREA THAT MAY FOSTER IMPACTS FROM CONVECTIVE COMPLEXES...WHILE AIDING IN SURFACE TROUGHING INLAND AS A FOCUS FOR CONVECTIVE INITIATION IN DURING DIURNAL WARMING. SEVERAL SHORT-WAVES EMBEDDED IN THE TROUGHING WILL PROVIDE A DAILY CHANCE OF THUNDERSTORMS. COLUMN MOISTURE WILL BE INCREASING BEGINNING WEDNESDAY AS SUBSIDENCE ALOFT WANES. THE LOW-LEVEL WSW FLOW WILL LIKELY BRING MAXIMUM TEMPERATURES IN THE PERIOD NEAR TO SLIGHTLY ABOVE LATE JUNE/EARLY JULY STANDARDS. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 18Z...FIRST WAVE OF CONVECTION MOVING THROUGH THE REGION WITH A BIT OF A LULL EXPECTED LATER THIS AFTERNOON. HIGH PWATS WILL GIVE US BRIEF PERIODS OF IFR VISIBILITIES IN THE HEAVIEST CONVECTION. STRONG SOUTHWEST FLOW WILL CONTINUE INTO THE EVENING HOURS. THE FRONT APPROACHES FROM THE WEST TONIGHT. THE HRRR MODEL DOES NOT HAVE THAT MUCH CONVECTION ALONG AND AHEAD OF THE FRONT...BUT THINK THINGS WILL BE FAIRLY ACTIVE OVERNIGHT. THE NAM STALLS THE FRONT ALONG THE COAST ON SUNDAY...BUT THINK WE WILL GET ENOUGH OF A WESTERLY WIND BY MID TO LATE MORNING TO KEEP CONVECTION EAST OF THE COASTAL TERMINALS...CERTAINLY WEST OF THE INLAND TERMINALS. EXTENDED OUTLOOK...VFR THROUGH TUESDAY. POSSIBLE AFTERNOON SHOWERS AND STORMS WEDNESDAY AND THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 948 AM SATURDAY...S TO SW WINDS AROUND 15 KT THIS MORNING WILL RAMP UP TO 20 TO 25 KT THIS AFTERNOON AND CONTINUE TONIGHT. SEAS 3 TO 4 FT ATTM WILL BUILD TO 5 TO 7 FT BY TONIGHT. AN SCA IS IN EFFECT FOR ALL WATERS FROM NOON TODAY THROUGH NOON SUNDAY. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE ALSO IN THE FORECAST AND MAY PRODUCE LOCALLY HIGHER WINDS AND SEAS. SEA SPECTRUM DOMINATED BY SW WAVES 3-4 FT EVERY 5 SECONDS TODAY AND SW WAVES 4-6 FT EVERY 6 SECONDS TONIGHT. TSTMS WILL BE CAPABLE OF GUSTS TO 50 KT TONIGHT INTO EARLY SUNDAY. MARINERS ARE ENCOURAGED TO OBTAIN A RADAR UPDATE BEFORE VENTURING OUT. SHORT TERM /SUNDAY THROUGH MONDAY/... AS OF 300 AM SATURDAY...COLD FRONT WILL APPROACH FROM THE WEST AND THEN STALL JUST INLAND OR RIGHT ALONG THE COAST MUCH OF SUNDAY. THIS WILL MAINTAIN SW WINDS ACROSS THE WATERS THROUGH THE LATTER HALF OF THE WKND...ALTHOUGH A VERY BRIEF TURN TO THE NORTH IS POSSIBLE LATE SUNDAY NIGHT INTO MONDAY ACROSS THE NORTHERN WATERS AS THE COLD FRONT SURGES SOUTHEAST. THIS WIND SHIFT WILL BE SHORT AND WITH VERY LIGHT SPEEDS...AS SW WINDS ARE EXPECTED TO RETURN AGAIN BY MONDAY AFTN. STRONGEST WINDS WILL BE AHEAD OF THE FRONT SUNDAY...WHEN SPEEDS WILL REACH 15-20 KTS...FALLING TO 10-15 KTS ON MONDAY. AN SCA IS IN EFFECT THROUGH NOON FOR A FEW 6 FT SEAS LEFTOVER FROM SATURDAY...BUT THESE WILL FALL THROUGH SUNDAY...AND BECOME 3-4 FT BY MONDAY WITH THE SW WIND CHOP REMAINING PREDOMINANT. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 828 AM SATURDAY...MODERATE SW WINDS PREVAIL THIS PERIOD AS INLAND SURFACE TROUGHING INTERACTS WITH HIGH PRESSURE OFFSHORE YIELDING SW 10-20 KT FLOW. TSTMS MAY IMPACT INSHORE WATERS IN THE LATE AFTERNOONS THROUGH THE OVERNIGHT PERIODS. SEAS MAINLY 3-4 FT BUT UP TO 5 FT OFFSHORE AT TIMES...AS INLAND TROUGHING SHARPENS INTO MID-WEEK. SPECTRAL DATA SUGGEST SEAS WILL BE COMPRISED OF 3 FOOT WAVES FROM THE SSW EVERY 6 SECONDS...AND 1-2 FOOT WAVES FROM THE ESE EVERY 7-9 SECONDS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT SUNDAY FOR AMZ250-252-254- 256. && $$ NEAR TERM...MJC SHORT TERM...JDW LONG TERM...MJC AVIATION...DL/8
AREA FORECAST DISCUSSION
NWS BISMARCK ND
247 PM CDT SAT JUN 27 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 247 PM CDT SAT JUN 27 2015 MAIN FORECAST ISSUE IS THUNDERSTORM COVERAGE AND SEVERE POTENTIAL AS COLD FRONT CONTINUES TO MOVE ACROSS THE STATE. AS OF 19Z THE FRONT HAD CROSSED ROLLA...BISMARCK AND HETTINGER. WATER VAPOR IMAGERY SHOWED DISTINCT SHORTWAVE OVER SOUTHERN MANITOBA MOVING TOWARD EASTERN NORTH DAKOTA IN NORTHWEST FLOW. WESTERN AND CENTRAL ND REMAIN ON WESTERN FLANK OF 110KT JET STREAK...IN LESS FAVORABLE ANTICYCLONIC SHEAR SIDE. TEMPERATURES WERE IN THE 80S WITH DEWPOINTS IN THE 60S ACROSS THE REGION. SPC MESO ANALYSIS PAGE SHOWS 2000-3000 J/KG OF SB CAPE AHEAD OF THE FRONT OVER THE SOUTHEASTERN CWA WITH A LITTLE CIN IN PLACE AS OF 19Z. EFFECTIVE SHEAR OF 40-50KTS WAS ALSO IN PLACE. HOWEVER...MID- LEVEL LAPSE RATES WERE SOMEWHAT LIMITED ACROSS THIS AREA HOWEVER WHICH MAY BE LIMITING DEVELOPMENT EARLY THIS AFTERNOON. THE HRRR HAS HANDLED THE SURFACE FEATURES WELL...ALTHOUGH IT HAS OVERDONE CONVECTION ACROSS OUR SOUTHWEST. THINK BEST CHANCE FOR CONVECTIVE DEVELOPMENT AND POSSIBLY SEVERE STORMS WILL BE IN SOUTHERN JAMES RIVER VALLEY REGION AS INFLUENCE OF UPPER LEVEL SHORTWAVE INCREASES ACROSS THE AREA. JUST HAD CONF CALL WITH SPC AND WILL ISSUE TORNADO WATCH FOR OUR 4 SOUTHEAST COUNTIES OF FOSTER...STUTSMAN...LAMOURE AND DICKEY. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 247 PM CDT SAT JUN 27 2015 THE DRY AND VERY WARM WEATHER CONTINUES INTO THE LONG TERM UNDER THE MID LEVEL RIDGE BEFORE A MID WEEK SPELL...TUESDAY THROUGH THURSDAY...OF COOLER AND LIKELY STORMY WEATHER. THIS AS THE RIDGE BREAKS DOWN IN RESPONSE TO ADVANCING SHORT WAVES MOVING THROUGH IT. IT IS A MINI PARADE OF WAVES IN THE NORTHWEST FLOW SO TIMING OF THE WAVES WILL BE KEY FOR TIMING OF THE STORM CHANCES. FOR NOW BLANKETED THE PERIOD WITH POPS AS THIS FAR OUT TO TRY AND PICK DRY TIMES IS NOT REALISTIC. THE RIDGE BUILDS BACK NORTH BY THE END OF THE WORK WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1259 PM CDT SAT JUN 27 2015 VFR CONDITIONS EXPECTED THROUGH THE TIME PERIOD. COLD FRONT IS CROSSING THE STATE WITH WINDS SHIFTING FROM THE NORTHWEST BEHIND THE FRONT. CONTINUED VCTS FOR KBIS AND KJMS THROUGH LATE AFTERNOON. THE BEST CHANCE FOR A THUNDERSTORM WOULD BE NEAR KJMS THIS AFTERNOON. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...JNS LONG TERM...JPM AVIATION...JNS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1143 AM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1143 AM CDT SAT JUN 27 2015 QUICK UPDATE TO ADJUST POPS SLIGHTLY FOR AFTERNOON CONVECTION. OVERALL...FORECAST IS ON TRACK. STARTING TO SEE SOME LIGHT RADAR RETURNS OVER KIDDER COUNTY. LATEST SPC UPDATE TO DAY 1 HAS PUT THE RED RIVER VALLEY INTO ENHANCED CATEGORY FOR SEVERE...BUT NO CHANGES OVER OUR AREA WITH SLIGHT RISK AREA CLIPPING OUR FAR EAST CENTRAL AND SOUTHEAST COUNTIES. UPDATE ISSUED AT 935 AM CDT SAT JUN 27 2015 A FEW THUNDERSTORMS IN ROLETTE COUNTY HAVE EXITED THAT AREA OVER THE LAST HOUR. BASED ON CURRENT RADAR...SATELLITE AND SHORT RANGE MODELS...REMOVED LOW POPS FOR THE NEXT FEW HOURS. OTHERWISE...WEAK FRONT HAS MOVED THROUGH WILLISTON AS OF 14Z. 12Z NAM IS COMING IN NOW AND APPEARS TO BE CONSISTENT WITH PREVIOUS RUN. MAIN ISSUE TODAY WILL BE THUNDERSTORM COVERAGE AND POSSIBILITY OF SEVERE. HIGH RES MODELS CONTINUE TO SHOW INITIATION OF ISOLATED/SCATTERED STORMS AFTER 18Z. NAM/GFS KEEP BEST COVERAGE ON CYCLONIC SHEAR SIDE OF 110KT JET STREAK...MAINLY TO OUR EAST...THAT IS NOSING INTO NORTH CENTRAL ND AT THIS TIME. HOWEVER THERE IS STILL 1000+ J/KG CAPE AHEAD OF THE FRONT...MAINLY ACROSS OUR SOUTHEASTERN AREA THIS AFTERNOON. WILL CONTINUE TO CARRY ISOLATED/SCATTERED COVERAGE FOR THIS AFTERNOON AND EARLY EVENING. SPC HAS CONTINUED TO KEEP THE JAMES RIVER VALLEY IN SLIGHT CHANCE FOR SEVERE THIS AFTERNOON. UPDATE ISSUED AT 649 AM CDT SAT JUN 27 2015 REGIONAL RADAR MOSAIC SHOWS MUCH OF THE SHOWER / THUNDERSTORM ACTIVITY HAS DIMINISHED EARLY THIS MORNING. THE LATEST HRRR AND RAP 13 STILL SUGGEST AN ISOLATED SHOWER OR STORM IS POSSIBLE THIS MORNING IN THE CENTRAL AND EAST....SO WILL KEEP A SMALL CHANCE IN THE FORECAST. DID NOT CHANGE MUCH FOR THIS AFTERNOON WITH HIGH RESOLUTION MODELS CONTINUING TO FOCUS THE THUNDERSTORM CHANCES TOWARDS THE JAMES RIVER VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 259 AM CDT SAT JUN 27 2015 MAIN CONCERN IS THE POTENTIAL FOR SEVERE THUNDERSTORMS THIS AFTERNOON/EARLY EVENING OVER EAST CENTRAL NORTH DAKOTA...FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE LATEST WATER VAPOR IMAGERY SHOWS NORTHWESTERLY FLOW INTO NORTH DAKOTA WITH A MID LEVEL SHORTWAVE PUSHING THROUGH NORTHWEST AND NORTH CENTRAL NORTH DAKOTA. LOCAL RADAR SHOWS ISOLATED SHOWERS DWINDLING...HOWEVER AN AREA OF THUNDERSTORMS OVER SOUTHEAST SASKATCHEWAN AND SOUTHWEST MANITOBA...WERE MOVING TOWARD THE TURTLE MOUNTAINS BUT SHOWING SIGNS OF WEAKENING. FARTHER UPSTREAM...A STRONGER MID LEVEL SHORTWAVE WITH AN 80KT JET STREAK OVER CENTRAL SASKATCHEWAN WAS ALSO MOVING SOUTHEAST WITH TIME. AT THE SURFACE...3HR PRESSURE FALLS WERE MAXIMIZED OVER SOUTHERN SASKATCHEWAN/MANITOBA...AHEAD OF AN ADVANCING COLD FRONT IN CENTRAL SASKATCHEWAN AND NORTH CENTRAL MONTANA. TIMING AND PLACEMENT OF THE COLD FRONT WILL DETERMINE THE COVERAGE AND INTENSITY OF SEVERE WEATHER POTENTIAL. THE HIGH RESOLUTION MODELS SUGGEST THE GREATEST RISK FOR SEVERE WEATHER RESIDES IN THE JAMES RIVER VALLEY...WITH MORE UNCERTAINTY NORTH IN THE TURTLE MOUNTAINS. THE GLOBAL MODELS KEEP THE BEST DYNAMICS EAST...WHERE THE SHORTWAVE AND JET STREAK WILL INTERACT WITH HIGHER INSTABILITY THIS AFTERNOON. THIS IS IN LINE WITH THE SLIGHT RISK PER SPC CONVECTIVE OUTLOOK. HOWEVER CAPE VALUES RANGING BETWEEN 1500-2000 J/KG AND 0-6KM BULK SHEAR OF 45KT TO 55KT ARE FORECAST ACROSS THE JAMES RIVER VALLEY BY MID TO LATE AFTERNOON...NEAR OR JUST PRIOR TO FRONTAL PASSAGE. THE CAPE/SHEAR VALUES DECREASE NORTH INTO THE TURTLE MOUNTAINS...BUT STILL MAY POSE A THREAT...ALBEIT A LESSER THREAT AS MENTIONED ABOVE. LATEST SPC CONVECTIVE OUTLOOK HAS A SHARP GRADIENT BETWEEN GENERAL/MARGINAL/SLIGHT RISK OVER EAST CENTRAL NORTH DAKOTA TODAY...WHICH COULD CHANGE LATER THIS MORNING AS NEWER DATA BECOMES AVAILABLE. FOR NOW...HAVE INJECTED SEVERE THUNDERSTORM WORDING INTO THE FORECAST PRODUCTS FROM NEAR THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. OTHERWISE NORTHWEST FLOW WITH EMBEDDED SHORTWAVES AHEAD OF THE MAIN FEATURE THIS AFTERNOON WILL LIKELY RENEW ISOLATED SHOWERS AND THUNDERSTORMS THROUGH THE MORNING HOURS IN CENTRAL NORTH DAKOTA. HAVE INCLUDED THIS IN THE MORNING FORECAST. NORTHWEST WINDS 15KT TO 25KT WILL DEVELOP BEHIND THE COLD FRONT THIS AFTERNOON WEST AND CENTRAL. DRY CONDITIONS WEST TODAY. H85 TEMPS WARM BY ANOTHER 3C TO 4C WHICH YIELDS AFTERNOON HIGHS IN THE UPPER 80S TO AROUND 90. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 259 AM CDT SAT JUN 27 2015 DRY WEATHER IS EXPECTED TO START THE LONG TERM PERIOD...THOUGH CAN`T COMPLETELY RULE OUT A ROGUE SHOWER OR THUNDERSTORM SUNDAY NIGHT AS PER THE GFS. BY MONDAY NIGHT...WEST / NORTHWEST FLOW WILL BE IN PLACE ALOFT WITH PERIODIC WAVES MOVING ACROSS THE NORTHERN PLAINS. WILL GENERALLY FOLLOW A MODEL BLEND WHICH KEEPS A CHANCE OF THUNDERSTORMS MUCH OF NEXT WEEK. TEMPERATURES WILL START OUT ON THE WARM SIDE OF AVERAGE...WITH MONDAY APPEARING TO BE THE WARMEST DAY OF THE PERIOD. THE REST OF THE WEEK SHOULD BE RELATIVELY SEASONABLE WITH HIGHS IN THE MID 70S TO LOWER 80S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 649 AM CDT SAT JUN 27 2015 A COLD FRONT WILL MOVE ACROSS WESTERN AND CENTRAL NORTH DAKOTA SATURDAY...WITH WINDS SHIFTING TO THE NORTHWEST BETWEEN 15KT AND 25KT. THE HIGHEST THREAT FOR A THUNDERSTORM SATURDAY AFTERNOON RESIDES AT KJMS FROM 21Z SATURDAY THROUGH 00Z SUNDAY. HAVE A VCTS MENTION AT KJMS UNTIL SOMETHING MORE DEFINITIVE DEVELOPS. ALSO HAVE INTRODUCED A VCTS AT KBIS BETWEEN 17Z AND 22Z SATURDAY...JUST PRIOR TO THE COLD FRONTAL PASSAGE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JNS SHORT TERM...KS LONG TERM...CK AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
935 AM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 935 AM CDT SAT JUN 27 2015 A FEW THUNDERSTORMS IN ROLETTE COUNTY HAVE EXITED THAT AREA OVER THE LAST HOUR. BASED ON CURRENT RADAR...SATELLITE AND SHORT RANGE MODELS...REMOVED LOW POPS FOR THE NEXT FEW HOURS. OTHERWISE...WEAK FRONT HAS MOVED THROUGH WILLISTON AS OF 14Z. 12Z NAM IS COMING IN NOW AND APPEARS TO BE CONSISTENT WITH PREVIOUS RUN. MAIN ISSUE TODAY WILL BE THUNDERSTORM COVERAGE AND POSSIBILITY OF SEVERE. HIGH RES MODELS CONTINUE TO SHOW INITIATION OF ISOLATED/SCATTERED STORMS AFTER 18Z. NAM/GFS KEEP BEST COVERAGE ON CYCLONIC SHEAR SIDE OF 110KT JET STREAK...MAINLY TO OUR EAST...THAT IS NOSING INTO NORTH CENTRAL ND AT THIS TIME. HOWEVER THERE IS STILL 1000+ J/KG CAPE AHEAD OF THE FRONT...MAINLY ACROSS OUR SOUTHEASTERN AREA THIS AFTERNOON. WILL CONTINUE TO CARRY ISOLATED/SCATTERED COVERAGE FOR THIS AFTERNOON AND EARLY EVENING. SPC HAS CONTINUED TO KEEP THE JAMES RIVER VALLEY IN SLIGHT CHANCE FOR SEVERE THIS AFTERNOON. UPDATE ISSUED AT 649 AM CDT SAT JUN 27 2015 REGIONAL RADAR MOSAIC SHOWS MUCH OF THE SHOWER / THUNDERSTORM ACTIVITY HAS DIMINISHED EARLY THIS MORNING. THE LATEST HRRR AND RAP 13 STILL SUGGEST AN ISOLATED SHOWER OR STORM IS POSSIBLE THIS MORNING IN THE CENTRAL AND EAST....SO WILL KEEP A SMALL CHANCE IN THE FORECAST. DID NOT CHANGE MUCH FOR THIS AFTERNOON WITH HIGH RESOLUTION MODELS CONTINUING TO FOCUS THE THUNDERSTORM CHANCES TOWARDS THE JAMES RIVER VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 259 AM CDT SAT JUN 27 2015 MAIN CONCERN IS THE POTENTIAL FOR SEVERE THUNDERSTORMS THIS AFTERNOON/EARLY EVENING OVER EAST CENTRAL NORTH DAKOTA...FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE LATEST WATER VAPOR IMAGERY SHOWS NORTHWESTERLY FLOW INTO NORTH DAKOTA WITH A MID LEVEL SHORTWAVE PUSHING THROUGH NORTHWEST AND NORTH CENTRAL NORTH DAKOTA. LOCAL RADAR SHOWS ISOLATED SHOWERS DWINDLING...HOWEVER AN AREA OF THUNDERSTORMS OVER SOUTHEAST SASKATCHEWAN AND SOUTHWEST MANITOBA...WERE MOVING TOWARD THE TURTLE MOUNTAINS BUT SHOWING SIGNS OF WEAKENING. FARTHER UPSTREAM...A STRONGER MID LEVEL SHORTWAVE WITH AN 80KT JET STREAK OVER CENTRAL SASKATCHEWAN WAS ALSO MOVING SOUTHEAST WITH TIME. AT THE SURFACE...3HR PRESSURE FALLS WERE MAXIMIZED OVER SOUTHERN SASKATCHEWAN/MANITOBA...AHEAD OF AN ADVANCING COLD FRONT IN CENTRAL SASKATCHEWAN AND NORTH CENTRAL MONTANA. TIMING AND PLACEMENT OF THE COLD FRONT WILL DETERMINE THE COVERAGE AND INTENSITY OF SEVERE WEATHER POTENTIAL. THE HIGH RESOLUTION MODELS SUGGEST THE GREATEST RISK FOR SEVERE WEATHER RESIDES IN THE JAMES RIVER VALLEY...WITH MORE UNCERTAINTY NORTH IN THE TURTLE MOUNTAINS. THE GLOBAL MODELS KEEP THE BEST DYNAMICS EAST...WHERE THE SHORTWAVE AND JET STREAK WILL INTERACT WITH HIGHER INSTABILITY THIS AFTERNOON. THIS IS IN LINE WITH THE SLIGHT RISK PER SPC CONVECTIVE OUTLOOK. HOWEVER CAPE VALUES RANGING BETWEEN 1500-2000 J/KG AND 0-6KM BULK SHEAR OF 45KT TO 55KT ARE FORECAST ACROSS THE JAMES RIVER VALLEY BY MID TO LATE AFTERNOON...NEAR OR JUST PRIOR TO FRONTAL PASSAGE. THE CAPE/SHEAR VALUES DECREASE NORTH INTO THE TURTLE MOUNTAINS...BUT STILL MAY POSE A THREAT...ALBEIT A LESSER THREAT AS MENTIONED ABOVE. LATEST SPC CONVECTIVE OUTLOOK HAS A SHARP GRADIENT BETWEEN GENERAL/MARGINAL/SLIGHT RISK OVER EAST CENTRAL NORTH DAKOTA TODAY...WHICH COULD CHANGE LATER THIS MORNING AS NEWER DATA BECOMES AVAILABLE. FOR NOW...HAVE INJECTED SEVERE THUNDERSTORM WORDING INTO THE FORECAST PRODUCTS FROM NEAR THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. OTHERWISE NORTHWEST FLOW WITH EMBEDDED SHORTWAVES AHEAD OF THE MAIN FEATURE THIS AFTERNOON WILL LIKELY RENEW ISOLATED SHOWERS AND THUNDERSTORMS THROUGH THE MORNING HOURS IN CENTRAL NORTH DAKOTA. HAVE INCLUDED THIS IN THE MORNING FORECAST. NORTHWEST WINDS 15KT TO 25KT WILL DEVELOP BEHIND THE COLD FRONT THIS AFTERNOON WEST AND CENTRAL. DRY CONDITIONS WEST TODAY. H85 TEMPS WARM BY ANOTHER 3C TO 4C WHICH YIELDS AFTERNOON HIGHS IN THE UPPER 80S TO AROUND 90. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 259 AM CDT SAT JUN 27 2015 DRY WEATHER IS EXPECTED TO START THE LONG TERM PERIOD...THOUGH CAN`T COMPLETELY RULE OUT A ROGUE SHOWER OR THUNDERSTORM SUNDAY NIGHT AS PER THE GFS. BY MONDAY NIGHT...WEST / NORTHWEST FLOW WILL BE IN PLACE ALOFT WITH PERIODIC WAVES MOVING ACROSS THE NORTHERN PLAINS. WILL GENERALLY FOLLOW A MODEL BLEND WHICH KEEPS A CHANCE OF THUNDERSTORMS MUCH OF NEXT WEEK. TEMPERATURES WILL START OUT ON THE WARM SIDE OF AVERAGE...WITH MONDAY APPEARING TO BE THE WARMEST DAY OF THE PERIOD. THE REST OF THE WEEK SHOULD BE RELATIVELY SEASONABLE WITH HIGHS IN THE MID 70S TO LOWER 80S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 649 AM CDT SAT JUN 27 2015 A COLD FRONT WILL MOVE ACROSS WESTERN AND CENTRAL NORTH DAKOTA SATURDAY...WITH WINDS SHIFTING TO THE NORTHWEST BETWEEN 15KT AND 25KT. THE HIGHEST THREAT FOR A THUNDERSTORM SATURDAY AFTERNOON RESIDES AT KJMS FROM 21Z SATURDAY THROUGH 00Z SUNDAY. HAVE A VCTS MENTION AT KJMS UNTIL SOMETHING MORE DEFINITIVE DEVELOPS. ALSO HAVE INTRODUCED A VCTS AT KBIS BETWEEN 17Z AND 22Z SATURDAY...JUST PRIOR TO THE COLD FRONTAL PASSAGE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JNS SHORT TERM...KS LONG TERM...CK AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
650 AM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 649 AM CDT SAT JUN 27 2015 REGIONAL RADAR MOSAIC SHOWS MUCH OF THE SHOWER / THUNDERSTORM ACTIVITY HAS DIMINISHED EARLY THIS MORNING. THE LATEST HRRR AND RAP 13 STILL SUGGEST AN ISOLATED SHOWER OR STORM IS POSSIBLE THIS MORNING IN THE CENTRAL AND EAST....SO WILL KEEP A SMALL CHANCE IN THE FORECAST. DID NOT CHANGE MUCH FOR THIS AFTERNOON WITH HIGH RESOLUTION MODELS CONTINUING TO FOCUS THE THUNDERSTORM CHANCES TOWARDS THE JAMES RIVER VALLEY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 259 AM CDT SAT JUN 27 2015 MAIN CONCERN IS THE POTENTIAL FOR SEVERE THUNDERSTORMS THIS AFTERNOON/EARLY EVENING OVER EAST CENTRAL NORTH DAKOTA...FROM THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. THE LATEST WATER VAPOR IMAGERY SHOWS NORTHWESTERLY FLOW INTO NORTH DAKOTA WITH A MID LEVEL SHORTWAVE PUSHING THROUGH NORTHWEST AND NORTH CENTRAL NORTH DAKOTA. LOCAL RADAR SHOWS ISOLATED SHOWERS DWINDLING...HOWEVER AN AREA OF THUNDERSTORMS OVER SOUTHEAST SASKATCHEWAN AND SOUTHWEST MANITOBA...WERE MOVING TOWARD THE TURTLE MOUNTAINS BUT SHOWING SIGNS OF WEAKENING. FARTHER UPSTREAM...A STRONGER MID LEVEL SHORTWAVE WITH AN 80KT JET STREAK OVER CENTRAL SASKATCHEWAN WAS ALSO MOVING SOUTHEAST WITH TIME. AT THE SURFACE...3HR PRESSURE FALLS WERE MAXIMIZED OVER SOUTHERN SASKATCHEWAN/MANITOBA...AHEAD OF AN ADVANCING COLD FRONT IN CENTRAL SASKATCHEWAN AND NORTH CENTRAL MONTANA. TIMING AND PLACEMENT OF THE COLD FRONT WILL DETERMINE THE COVERAGE AND INTENSITY OF SEVERE WEATHER POTENTIAL. THE HIGH RESOLUTION MODELS SUGGEST THE GREATEST RISK FOR SEVERE WEATHER RESIDES IN THE JAMES RIVER VALLEY...WITH MORE UNCERTAINTY NORTH IN THE TURTLE MOUNTAINS. THE GLOBAL MODELS KEEP THE BEST DYNAMICS EAST...WHERE THE SHORTWAVE AND JET STREAK WILL INTERACT WITH HIGHER INSTABILITY THIS AFTERNOON. THIS IS IN LINE WITH THE SLIGHT RISK PER SPC CONVECTIVE OUTLOOK. HOWEVER CAPE VALUES RANGING BETWEEN 1500-2000 J/KG AND 0-6KM BULK SHEAR OF 45KT TO 55KT ARE FORECAST ACROSS THE JAMES RIVER VALLEY BY MID TO LATE AFTERNOON...NEAR OR JUST PRIOR TO FRONTAL PASSAGE. THE CAPE/SHEAR VALUES DECREASE NORTH INTO THE TURTLE MOUNTAINS...BUT STILL MAY POSE A THREAT...ALBEIT A LESSER THREAT AS MENTIONED ABOVE. LATEST SPC CONVECTIVE OUTLOOK HAS A SHARP GRADIENT BETWEEN GENERAL/MARGINAL/SLIGHT RISK OVER EAST CENTRAL NORTH DAKOTA TODAY...WHICH COULD CHANGE LATER THIS MORNING AS NEWER DATA BECOMES AVAILABLE. FOR NOW...HAVE INJECTED SEVERE THUNDERSTORM WORDING INTO THE FORECAST PRODUCTS FROM NEAR THE TURTLE MOUNTAINS SOUTH INTO THE JAMES RIVER VALLEY. OTHERWISE NORTHWEST FLOW WITH EMBEDDED SHORTWAVES AHEAD OF THE MAIN FEATURE THIS AFTERNOON WILL LIKELY RENEW ISOLATED SHOWERS AND THUNDERSTORMS THROUGH THE MORNING HOURS IN CENTRAL NORTH DAKOTA. HAVE INCLUDED THIS IN THE MORNING FORECAST. NORTHWEST WINDS 15KT TO 25KT WILL DEVELOP BEHIND THE COLD FRONT THIS AFTERNOON WEST AND CENTRAL. DRY CONDITIONS WEST TODAY. H85 TEMPS WARM BY ANOTHER 3C TO 4C WHICH YIELDS AFTERNOON HIGHS IN THE UPPER 80S TO AROUND 90. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 259 AM CDT SAT JUN 27 2015 DRY WEATHER IS EXPECTED TO START THE LONG TERM PERIOD...THOUGH CAN`T COMPLETELY RULE OUT A ROGUE SHOWER OR THUNDERSTORM SUNDAY NIGHT AS PER THE GFS. BY MONDAY NIGHT...WEST / NORTHWEST FLOW WILL BE IN PLACE ALOFT WITH PERIODIC WAVES MOVING ACROSS THE NORTHERN PLAINS. WILL GENERALLY FOLLOW A MODEL BLEND WHICH KEEPS A CHANCE OF THUNDERSTORMS MUCH OF NEXT WEEK. TEMPERATURES WILL START OUT ON THE WARM SIDE OF AVERAGE...WITH MONDAY APPEARING TO BE THE WARMEST DAY OF THE PERIOD. THE REST OF THE WEEK SHOULD BE RELATIVELY SEASONABLE WITH HIGHS IN THE MID 70S TO LOWER 80S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 649 AM CDT SAT JUN 27 2015 A COLD FRONT WILL MOVE ACROSS WESTERN AND CENTRAL NORTH DAKOTA SATURDAY...WITH WINDS SHIFTING TO THE NORTHWEST BETWEEN 15KT AND 25KT. THE HIGHEST THREAT FOR A THUNDERSTORM SATURDAY AFTERNOON RESIDES AT KJMS FROM 21Z SATURDAY THROUGH 00Z SUNDAY. HAVE A VCTS MENTION AT KJMS UNTIL SOMETHING MORE DEFINITIVE DEVELOPS. ALSO HAVE INTRODUCED A VCTS AT KBIS BETWEEN 17Z AND 22Z SATURDAY...JUST PRIOR TO THE COLD FRONTAL PASSAGE. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CK SHORT TERM...KS LONG TERM...CK AVIATION...KS
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1212 AM CDT SAT JUN 27 2015 .UPDATE... ISSUED AT 1212 AM CDT SAT JUN 27 2015 LATEST LOCAL RADAR SHOWS A BROKEN AREA/LINE OF CONVECTION STRETCHING FROM CARTWRIGHT IN MCKENZIE COUNTY...NORTHEAST TO KENMARE AND ACROSS THE CANADIAN BORDER INTO SOUTHERN MANITOBA. MID LEVEL SHORTWAVE EMBEDDED WITHIN A NORTHWESTERLY FLOW ALOFT WAS CONTRIBUTING TO 7.5 C/KM MID LEVEL LAPSE RATES IN THE THUNDERSTORM AREA. LATEST SPC MESOANALYSIS SHOWS ELEVATED CAPE OF 1000-3000 J/KG AND 0-6KM SHEAR OF AROUND 40KT. NO GLOBAL OR HIGH RESOLUTION MODEL IS ACCURATELY HANDLING THIS SCENARIO WELL. MAIN CHALLENGE WILL BE TO FORECAST THIS AREA AS IT MOVES SOUTHEAST OVERNIGHT. PATTERN RECOGNITION ALONG WITH CURRENT SHORTWAVE SUGGESTS PERIODS OF WEAKENING/DIMINISHING OF CURRENT ACTIVITY...BUT ALSO NEW ISOLATED CELLS RANDOMLY DEVELOPING AHEAD OF THE AFOREMENTIONED AREA. THIS IS WHAT IS OCCURRING NOW AND EXPECT IT TO CONTINUE. FOR NOW HAVE EXTENDED THE ISOLATED SHOWER/THUNDERSTORM AREA TO NEAR SOUTHWEST AND SOUTH CENTRAL NORTH DAKOTA AND WILL ADJUST IF NECESSARY THROUGH THE OVERNIGHT PERIOD. REST OF FORECAST REMAINS ON TRACK. UPDATE ISSUED AT 919 PM CDT FRI JUN 26 2015 REMOVED POPS SOUTH FOR THE REST OF TONIGHT. BROKEN LINE OF SHOWERS AND THUNDERSTORMS FROM NORTHWEST MONTANA BACK NORTHEAST INTO SOUTHWESTERN MANITOBA CONTINUES TO PUSH SOUTH ALONG AN INVERTED SFC TROUGH AXIS. THIS ACTIVITY HAS BEEN DECREASING IN COVERAGE AND INTENSITY ALL EVENING AS THEY NEAR THE CANADIAN BORDER...SO LEFT POPS IN THE SLIGHT CHANCE CATEGORY WITH THIS FORECAST ISSUANCE ACROSS THE NORTH. UPDATE ISSUED AT 643 PM CDT FRI JUN 26 2015 SCALED BACK ON POPS A BIT TO BETTER REFLECT LATEST RADAR IMAGERY AND NEAR TERM HIGH RES MODEL OUTPUT. OVERALL THE FORECAST IS IN GOOD SHAPE. UPDATE ISSUED AT 504 PM CDT FRI JUN 26 2015 CONFINED POPS TO THE MORE DENSE CU FIELDS...SOUTHWEST AND EAST...ALSO WHERE RADAR RETURNS ARE AT. OTHERWISE UPDATES WERE MINOR FOR THIS FORECAST ISSUANCE. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 238 PM CDT FRI JUN 26 2015 THUNDERSTORM POTENTIAL THIS AFTERNOON THROUGH TONIGHT AND A WARM SATURDAY HIGHLIGHT THE SHORT TERM FORECAST. THE 18 UTC RAP ANALYSIS DEPICTS 800-1500 J/KG OF ML CAPE FROM THE JAMES RIVER VALLEY THROUGH THE TURTLE MOUNTAINS AND INTO THE SOURIS BASIN...WITH DEEP LAYER SHEAR ON THE ORDER OF 20-25 KTS. RADAR TRENDS THROUGH 1940 UTC DEPICT ISOLATED CONVECTION INITIATING ACROSS THESE AREAS...WITH A FEW WEAK IMPULSES EMBEDDED IN NORTHWEST FLOW ALOFT. CANNOT RULE OUT A STRONG STORM WITH SMALL HAIL AND GUSTY WINDS...HOWEVER...ANY SEVERE THREAT AT THIS TIME APPEARS LOW. THESE AFTERNOON STORMS ARE EXPECTED TO FADE WITH SUNSET. ANOTHER ROUND OF STORMS ASSOCIATED WITH A WAVE ACROSS CENTRAL SASKATCHEWAN THIS AFTERNOON MAY PROPAGATE INTO NORTHERN NORTH DAKOTA TONIGHT. THESE STORMS ARE EXPECTED TO BE NON-SEVERE. ACROSS SOUTH CENTRAL NORTH DAKOTA AND THE JAMES RIVER VALLEY...A SIMILAR FOG SETUP TONIGHT IS EXPECTED WHICH PRODUCED FOG THIS MORNING FOR THESE AREAS. THUS...ADDED FOG FOR LATE TONIGHT INTO SATURDAY MORNING FOR THESE LOCATIONS. FOR SATURDAY...A WARM DAY IS FORECAST AHEAD OF A WEAK COLD FRONT THAT WILL PROPAGATE ACROSS WESTERN AND CENTRAL NORTH DAKOTA FROM SOUTHERN CANADA THROUGH THE AFTERNOON. WITH GOOD MIXING AND INSOLATION...WIDESPREAD HIGHS IN THE UPPER 80S TO LOWER 90S ARE EXPECTED...ON THE WARMER EDGE OF THE 12 UTC DETERMINISTIC AND STATISTICAL SUITES. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 238 PM CDT FRI JUN 26 2015 DETERMINISTIC AND ENSEMBLE MODELS INDICATE MAINLY DRY CONDITIONS TO BEGIN THE LONG TERM PERIOD. ALTHOUGH AN ISOLATED THUNDERSTORM CAN NOT BE COMPLETELY RULED OUT DUE TO DAYTIME HEATING. UPPER LEVEL RIDGING WILL BE THE DOMINANT FEATURE IN THE FORECAST SUNDAY AND MONDAY. SHORTWAVE ENERGY BEGINS TO MAKE ITS WAY THROUGH THE MEAN UPPER LEVEL RIDGE BEGINNING MONDAY NIGHT. WILL UTILIZE THE MODEL BLEND IN REGARDS TO POPS WHICH BRINGS SMALL CHANCES OF THUNDERSTORMS ACROSS AT LEAST PARTS OF WESTERN AND CENTRAL NORTH DAKOTA MONDAY NIGHT THROUGH FRIDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1212 AM CDT SAT JUN 27 2015 PATCHY FOG EXPECTED AT KBIS AND KJMS BETWEEN 09Z AND 14Z SATURDAY WITH VSBYS AT/AROUND 5SM. A COLD FRONT WILL SHIFT ACROSS WESTERN AND CENTRAL NORTH DAKOTA SATURDAY...WITH WINDS SHIFTING TO THE NORTHWEST BETWEEN 15KT AND 25KT. THE HIGHEST THREAT FOR A THUNDERSTORM SATURDAY AFTERNOON RESIDES AT KJMS FROM 21Z SATURDAY THROUGH 01Z SUNDAY. HAVE A VCTS MENTION FOR NOW AT KJMS WITH THE REST OF THE TERMINALS DRY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...AYD LONG TERM...TWH AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
910 PM EDT SUN JUN 28 2015 .SYNOPSIS... LOW PRESSURE WILL CONTINUE TO MOVE EASTWARD ACROSS NEW YORK TONIGHT. ANOTHER AREA OF LOW PRESSURE WILL MOVE ACROSS THE REGION ON MONDAY WITH A COLD FRONT STALLING ACROSS CENTRAL OHIO. THIS BOUNDARY WILL BECOME A FOCUS ON TUESDAY AS UPPER LEVEL JET ENERGY PASSES OVERHEAD. THE STALLED FRONTAL BOUNDARY MAY THEN PRODUCE ADDITIONAL SHOWERS AND THUNDERSTORMS ON WEDNESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... BACK EDGE OF STRATOCU HAS NOW MADE ITS WAY INTO NW PA. LAST FEW SHRA APPEAR TO JUST BE IN EASTERN ERIE CO PA. WILL CONTINUE TO RAMP DOWN POPS AND CLOUDS IN NW PA THRU MIDNIGHT BUT WILL KEEP LINGERING SLIGHT CHC FOR THE SNOWBELT LATER TONIGHT AS HRRR AND RAP INDICATE SOME LIGHT SHRA DEVELOPING SE INTO THE AREA. HIGHER CLOUDS FROM TOMORROW`S SYSTEM WILL CONTINUE TO SPREAD INTO THE WEST. CURRENT SHRA OVER INDIANA SHOULD DISSIPATE BEFORE REACHING THE WEST BUT ANOTHER PUSH IS EXPECTED LATE IN THE NIGHT. A FEW SHRA COULD REACH THE EXTREME WESTERN FRINGE AROUND DAYBREAK SO WILL KEEP A SMALL CHC POP THERE FOR THE LAST HOUR OF THE NIGHT. MOST OF THE CWA SHOULD DIP INTO THE 50S WITH THE LOWEST TEMPERATURES OVER THE INLAND PART OF THE EASTERN SNOWBELT WHERE LOWER 50S SHOULD BE COMMON. THE INCREASING CLOUDS AND DEVELOPING SOUTH WINDS IN THE WEST WILL PROBABLY HOLD LOWS IN A 58 TO 60 RANGE. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/... THE NEXT AREA OF LOW PRESSURE WILL MOVE ACROSS THE AREA ON MONDAY BUT THERE IS SOME UNCERTAINTY ON ITS EXACT TRACK. AT THIS POINT IT APPEARS THE CONVECTION THAT DEVELOPS OVER MISSOURI AND ILLINOIS WILL MOVE TOWARD THE REGION OVERNIGHT. THIS CONVECTION WILL ATTEMPT TO MOVE INTO NW OHIO NEAR OR SHORTLY AFTER SUNRISE. THIS CONVECTION SHOULD BE WEAKENING AS IS MOVES INTO THAT AREA. WE DID CONSIDER A FLOOD WATCH FOR NEW FLOODING BUT SINCE WE THINK THE QPF SHOULD BE UNDER HALF AN INCH WE HELD OFF FOR NOW. IF THIS CONVECTION CHARGES TOWARD THE AREA STRONGER THAN ANTICIPATED THEN THE FLOOD THREAT WILL HAVE TO BE REEVALUATED. AS THIS AREA OF LOW PRESSURE PASSES MONDAY EVENING IT WILL PUSH A WEAKENING COLD FRONT ACROSS THE AREA. THE BOUNDARY WILL STALL NEAR CENTRAL OHIO BUT EVEN THAT IS UNCERTAIN AT THIS POINT. THIS BOUNDARY AND A COUPLE PIECES OF JET ENERGY WILL THEN BE THE MAIN PLAYERS FR THE FORECAST ON TUESDAY AND WEDNESDAY. THE BEST CHANCES OF RAIN LOOK TO BE ACROSS THE SOUTHERN COUNTY WARNING AREA TUESDAY AFTERNOON. HIGH PRESSURE MAY BEGIN TO MOVE INTO THE AREA WEDNESDAY NIGHT FROM SOUTHERN CANADA. THE HIGH TEMPERATURE FORECASTS WILL CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES BUT COULD VARY SLIGHTLY DEPENDING ON THE AMOUNT OF CONVECTIVE DEBRIS CLOUDINESS EACH DAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... WISH THE HOLIDAY FORECAST WAS CUT AND DRY...BUT WITH THE EASTERN U.S. MAINTAINING A BROAD TROUGH...WILL STILL HAVE TO DEAL WITH UNSETTLED WEATHER. HAVE SIDED TOWARD AN ENSEMBLE SOLUTION TO TRY AND PINPOINT THE BETTER CHANCES OF PRECIPITATION. THEREFORE FOR NOW HAVE THE BEST CHANCES OF SHOWERS/THUNDERSTORMS BETWEEN FRIDAY AND FRIDAY NIGHT AS LOW PRESSURE MAY BE WORKING ACROSS THE LOWER GREAT LAKES. UNSURE WHETHER THE FRONT CLEARS HERE SO LINGERED SOME PRECIP CHANCES INTO SATURDAY. BY SUNDAY THROUGH ENS MEAN HAS A RIDGE BEGINNING TO MOVE ACROSS THE OHIO VALLEY. TEMPERATURES THROUGH THE PERIOD WILL BE SEASONABLE. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... WILL CONTINUE MVFR CONDITIONS AT KERI ANOTHER COUPLE HOURS BUT THEN ALL TERMINALS SHOULD BE VFR. THIS WILL CONTINUE THROUGH THE NIGHT ALTHOUGH DID BRING IN MVFR VISIBILITIES WITH FOG INLAND EAST TOWARDS MORNING. NEXT SYSTEM MOVES IN FROM THE WEST AFTER 12Z. EXPECT PRECIP TO REACH KFDY/KTOL 12-15Z TIME FRAME TAKING CONDITIONS TO MVFR. THIS WILL SPREAD EAST INTO THE AREA DURING THE DAY REACHING KMFD 16-20Z. HELD OFF MVFR CONDITIONS AT KCLE UNTIL AFTER 00Z. ALSO KEPT KCAK...KYNG AND KERI VFR THROUGH 00Z. OUTLOOK...NON VFR EXPECTED MONDAY NIGHT...POSSIBLY LINGERING INTO TUESDAY. AREAS OF NON VFR WEDNESDAY. && .MARINE... HAVE HAD TO EXTEND THE SMALL CRAFT ADVISORY INTO THE EVENING FOR EAST OF THE ISLANDS. BUOY OFF OF CLEVELAND AND REPORTS OFF OF ERIE PA STILL INDICATE 4 TO 5 FOOTERS. HIGH PRESSURE WILL ACROSS THE LAKE TONIGHT SO WIND/WAVES WILL SETTLE. NEXT SYSTEMS TRACK OF THE LOW FOR MONDAY INTO TUESDAY WILL BE CRITICAL TO THE EXACT DIRECTION AND SPEED OF THE WIND ON THE LAKE. HAVE TAKEN THE LOW ACROSS THE WESTERN BASIN AND INTO ONTARIO MONDAY NIGHT PRODUCING A STIFF ESE FLOW FOR THE WESTERN HALF OF THE LAKE MONDAY FOLLOWED BY SOUTHWEST WINDS TUESDAY. THERE ARE SOME SOLUTIONS THAT TAKE IT MORE ACROSS THE CENTER OF THE LAKE AND THEREFORE WOULD YIELD DIFFERENT WIND/WAVES ON THE LAKE. GRADIENT BECOMES MUCH WEAKER FOR MID WEEK AND WINDS WILL BE OF NO ISSUE. HIGH PRESSURE DOES NOT CLEANLY MAKE IT TO THE LAKE UNTIL MAYBE THURSDAY. ANOTHER SYSTEM LOOKS TO BE HEADED OUR WAY FOR FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...ADAMS/MULLEN SHORT TERM...MULLEN LONG TERM...OUDEMAN AVIATION...TK MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
441 PM EDT SAT JUN 27 2015 .SYNOPSIS... LOW PRESSURE WILL REMAIN NEAR THE AREA THROUGH SUNDAY...KEEPING OCCASIONAL RAIN AND SHOWERS IN THE FORECAST. THE WEATHER PATTERN WILL REMAIN ACTIVE WITH THE NEXT SYSTEM AFFECTING THE AREA MONDAY AND TUESDAY. HIGH PRESSURE WILL FINALLY BE ABLE TO BUILD ACROSS THE AREA FOR THURSDAY WITH FAIR WEATHER. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... LOW CENTER CURRENTLY NEAR CLEVELAND WITH THE OCCLUDED FRONT PRESSING EAST ACROSS EASTERN OHIO WITH SHOWERS AND A FEW THUNDERSTORMS ASSOCIATED WITH IT. FURTHER WEST HEAVY WRAP AROUND RAIN WILL CONTINUE TO AFFECT NORTHWEST OHIO THROUGH THE EVENING. HAVE TRIMMED THE FLOOD WATCH REMOVING THE SOUTHERN COUNTIES EARLY. HEAVY RAIN STILL LIKELY FOR NW OH IN THE WRAP AROUND AND ACROSS THE EAST WITH THE LINE OF CONVECTION. IN BETWEEN RUNOFF ACROSS FAR NORTH CENTRAL OHIO STILL CAUSING RISES. SEE LATEST RIVER FLOOD WARNINGS...AREAL FLOOD WARNINGS...AND FLOOD ADVISORIES. THE LOW WILL MAKE SLOW PROGRESS TONIGHT JUST REACHING NW PA BY MORNING. SO AREAS THAT HAVE A PRIMARILY DRY EVENING WILL SEE SHOWERS RETURN OVERNIGHT. RAINFALL AMOUNTS WILL BE MUCH LIGHTER AS THE SYSTEM SLOWLY WEAKENS. LATEST HRRR SUGGESTS THAT BY LATER THIS EVENING...THE RAINFALL IN NW OHIO WILL BE MUCH LIGHTER. SO WHILE PRECIP CHANCES STILL REMAIN VERY HIGH OVER THE AREA THROUGH THE NIGHT...THE RAIN WILL BE MUCH LIGHTER. WINDS WILL REMAIN STRONG ACROSS NW OHIO THIS EVENING...DIMINISHING TOWARD LATE EVENING. LAKESHORE FLOOD WARNING CONTINUES INTO THIS EVENING AS WELL AS WATER LEVELS REMAIN HIGH ON THE LAKE FROM THE PERSISTENT NE WINDS. PRECIP TOTALS SO FAR AS OF 20Z/4P: TOLEDO (TOL) 2.12 TOLEDO (TDZ) 2.55 CLEVELAND 2.76 YOUNGSTOWN 1.43 ERIE PA 1.18 && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY NIGHT/... UPPER LOW AND THERMAL TROUGH OVERHEAD ON SUNDAY. AGAIN RAIN CHANCES HIGH...BUT FOR MUCH LESS RAINFALL...JUST A COUPLE TENTHS OF AN INCH OR SO. TEMPERATURES WELL BELOW NORMAL...WITH AREAS ACROSS EASTERN OH/NW PA LIKELY NOT GETTING OUT OF THE 60S FOR HIGHS. FURTHER WEST SLOW IMPROVEMENT AND EVEN SOME BREAKS IN THE OVERCAST WILL YIELD AN AFTERNOON WITH HIGHS IN THE LOWER 70S. AREA WILL ONLY HAVE A SMALL BREAK IN BETWEEN SYSTEMS...SUNDAY NIGHT. THE NEXT SHORTWAVE MOVES OUT OF THE UPPER MIDWEST TO THE LOWER GREAT LAKES. LOW PRESSURE WILL TRACK ACROSS LOWER MI AND INTO ONTARIO. THE WARM FRONT LOOKS TO BE ACTIVE WITH UPPER SUPPORT. THIS IS UNFORTUNATE BECAUSE LIKELY PRECIP CHANCES WILL BE NEEDED ALREADY BY MONDAY ESPECIALLY ACROSS THE WESTERN HALF OF THE AREA. THE COLD FRONT ARRIVES ON TUESDAY. OF COURSE AFTER ALL OF THE RAIN WE HAVE HAD MORE WILL JUST KEEP THINGS SATURATED. WILL CONTINUE TO MONITOR THIS...BUT RAINFALL AMOUNTS WILL BE AROUND A HALF INCH. TEMPERATURES WILL CONTINUE TO BE LIMITED BY EXCESSIVE CLOUD COVER FOR THIS TIME OF YEAR...LOWER AND MID 70S BOTH MONDAY AND TUESDAY. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... HIGH PRESSURE WILL ATTEMPT TO BUILD IN ACROSS THE AREA ON WEDNESDAY. THERE MAY BE SOME LINGERING SHOWERS ACROSS THE EAST BUT FOR THE MOST PART IT WILL BEGIN TO DRY. THERE IS UNCERTAINTY ON THURSDAY ON HOW FAR NORTH LOW PRESSURE WILL BE LOCATED. HAVE KEPT THE PREVIOUS FORECAST UNTOUCHED WITH THE UNCERTAINTY. HIGHS THROUGH THE PERIOD WILL GENERALLY BE IN THE MIDDLE TO UPPER 70S. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... SURFACE LOW JUST TO THE SOUTHWEST OF KCLE MAKING FOR A DIFFICULT TAF FORECAST. VARIABLE CEILINGS GENERALLY IN THE MVFR/IFR LEVELS. MUCH OF THE IFR OCCURRING IN THE SHOWERS AND THUNDERSTORMS. WINDS HAVE BEEN THE GREATEST CHALLENGE WITH THE MODELS INCONSISTENT ON THE PATH OF THE SURFACE LOW. CENTRAL AND EASTERN AREAS WILL GENERALLY HAVE A SOUTHERLY WIND WITH LOCATIONS CLOSER TO THE LAKE HAVING NORTHEAST TO NORTH WINDS. THE STRONGEST WINDS WILL BE WEST OF THE SURFACE LOW...MAINLY FOR THE KTOL AREA. SHOWERS WILL LINGER ACROSS THE REGION INTO SUNDAY MORNING WITH MOST LOCATIONS IFR INTO MID MORNING. OUTLOOK...NON VFR EXPECTED SUNDAY IN SCATTERED SHOWERS. NON VFR EXPECTED AGAIN MONDAY/MONDAY NIGHT AND WEDNESDAY. && .MARINE... WATER LEVELS HAVE BEEN ELEVATED ACROSS THE WESTERN BASIN AS GALES PUSHED WATER ONSHORE. REPORTS ALONG THE LAKESHORE INDICATE THAT THERE HAS BEEN SOME FLOODING ACROSS OTTAWA AND PORTIONS OF LUCAS COUNTIES. WINDS MAY BEGIN TO DECREASE LATE IN THE EVENING AS THE SURFACE LOW DRIFTS UP THE LAKESHORE. HAVE MODIFIED THE GALE WARNING FOR JUST THE WESTERN BASIN. HOWEVER WAVES AND WINDS WILL BE STRONG ENOUGH TO KEEP A SMALL CRAFT ADVISORY GOING FROM CLEVELAND TO RIPLEY. WAVES ABOVE 4 FOOT ARE EXPECTED INTO SUNDAY MORNING SO WILL KEEP THE BEACH HAZARDS STATEMENT GOING. ANOTHER AREA OF LOW PRESSURE WILL MOVE ACROSS THE GREAT LAKES ON MONDAY WITH ITS WIND SHIFT. HIGH PRESSURE ATTEMPTS TO BUILD OVER THE REGION BY MID WEEK. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...BEACH HAZARDS STATEMENT THROUGH SUNDAY MORNING FOR OHZ003-007- 009>012-089. FLOOD WATCH UNTIL 4 AM EDT SUNDAY FOR OHZ003-006>014-017>019- 022-023-033-089. LAKESHORE FLOOD WARNING UNTIL 10 PM EDT THIS EVENING FOR OHZ003-007-009. PA...BEACH HAZARDS STATEMENT THROUGH SUNDAY MORNING FOR PAZ001. FLOOD WATCH UNTIL 4 AM EDT SUNDAY FOR PAZ001>003. MARINE...GALE WARNING UNTIL 3 AM EDT SUNDAY FOR LEZ142>145-162>165. SMALL CRAFT ADVISORY UNTIL 3 AM EDT SUNDAY FOR LEZ146>149. && $$ SYNOPSIS...OUDEMAN NEAR TERM...OUDEMAN SHORT TERM...OUDEMAN LONG TERM...MULLEN AVIATION...MULLEN MARINE...MULLEN
AREA FORECAST DISCUSSION
NWS PENDLETON OR
359 PM PDT SUN JUN 28 2015 UPDATED THE AVIATION DISCUSSION .SHORT TERM...TONIGHT THROUGH WEDNESDAY EVENING...WILL EXTEND THE HEAT ADVISORIES FOR MOST OF OUR BASIN ZONES THROUGH MONDAY EVENING. THIS EXTENSION IS DUE TO THE IMPACTS OF EXPECTED VERY WARM OVERNIGHT LOW TEMPS. MOST LOCATIONS IN THE BASIN WILL SEE OVERNIGHT LOWS IN THE 70S. AN UPPER LEVEL DISTURBANCE WILL MOVE INTO AND ACROSS THE PACIFIC NORTHWEST DURING THE NEXT 24 HOURS. THIS SYSTEM WILL CONTINUE TO TAP THE HOT, UNSTABLE AND INCREASINGLY MOIST AIR MASS OVER THE REGION RESULTING IN THUNDERSTORMS AND SHOWERS. SHOWERS AND STORMS HAVE THE POTENTIAL TO AFFECT ANY LOCATION WITHIN OUR AREA THROUGH TONIGHT. SOME STORMS HAVE THE POTENTIAL TO PRODUCE STRONG GUSTY WINDS THROUGH THIS EVENING. SPC CONTINUES TO HAVE THE WESTERN TWO THIRDS OF OUR AREA WITHIN A MARGINAL CHANCE OF SEVERE AREA. ON MONDAY THE CHANCES OF SHOWERS WILL DECREASE FROM THE WEST THROUGH THE DAY AS THE DISTURBANCE SHIFTS EAST ACROSS THE REGION. BY MONDAY AFTERNOON THE BEST COVERAGE OF SHOWERS AND STORMS WILL BE FROM THE BLUE MOUNTAINS EAST TO WALLOWA COUNTY. COULD SEE A FEW SHOWERS AND STORMS LINGER OVER OUR EASTERN MOST ZONES INTO MONDAY EVENING. LOCALLY BREEZY WINDS WILL BE POSSIBLE AT TIMES DUE TO INCREASING ONSHORE FLOW, ESPECIALLY THROUGH THE CASCADE GAPS TONIGHT THROUGH MONDAY EVENING. THIS ONSHORE FLOW WILL CAUSE HIGH TEMPS TO COOL, ESPECIALLY IN THE BASIN WHERE TEMPS SHOULD BE AROUND 10 DEGREES COOLER. THE UPPER RIDGE WILL BE SUPPRESSED SOUTH OF THE PACNW ON TUESDAY, THEN BEGIN TO BUILD NORTH INTO THE AREA WEDNESDAY. TEMPS WILL REMAIN ABOVE SEASONAL, BUT NOT AS WARM THIS WEEKEND. ALSO EXPECT DRY CONDITIONS ACROSS THE AREA AS MOISTURE WILL REMAIN SUPPRESSED OVER SOUTHERN OREGON AND NEVADA. 90 .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...A STRONG HIGH PRESSURE SYSTEM OVER NEVADA WILL REMAIN STATIONARY AND CONTINUE TO DOMINATE THE AREAS WEATHER WITH ABOVE NORMAL TEMPERATURES AND MAINLY DRY CONDITIONS FOR THE REMAINDER OF THE WEEK. ALTHOUGH THE HIGH PRESSURE SLIPS SOMEWHAT EAST NEXT WEEKEND IT WILL RETAIN A FIRM GRIP ON OUR AREAS WEATHER AS AFTN HIGH TEMPS REMAIN HOT WITH THE DRY CONDITIONS PERSISTING. && .AVIATION...A FEW THUNDERSTORMS WILL NEAR TAF SITES KPDT...KALW... KPSC AND ALSO KRDM AND KBDN THROUGH 04Z THAT WILL LOWER CEILINGS TOWARD 5K BUT VFR CONDITIONS SHOULD PREVAIL. AFTER 04Z TSRA COULD ALSO APPROACH KDLS AND KYKM AND LOWER CEILINGS TOWARD 5K WITH MAINLY VFR CONDITIONS. IN ADDITION BRIEF WIND GUSTS TO 30 KTS ARE POSSIBLE AT TAF SITE KDLS UNTIL 06S. OTHERWISE THE TAF SITES SHOULD REMAIN MOSTLY WITH VFR CONDITIONS INTO TOMORROW. && .FIRE WEATHER...ALL ZONES ARE CURRENTLY UNDER A RED FLAG WARNING. ISOLATED THUNDERSTORMS HAVE DEVELOPED OVER THE SOUTHERN BLUE MOUNTAINS THIS AFTERNOON...AND SCATTERED THUNDERSTORMS WILL DEVELOP IN THE NEXT SEVERAL HOURS ALONG THE EAST SLOPES OF THE CASCADES...THE OCHOCO MOUNTAINS...THE BLUE MOUNTAINS...AND ALONG THE OREGON BLUE MOUNTAIN FOOTHILLS. THE DEEPEST VERTICAL SHEAR WILL BE ALONG THE EAST SLOPES OF THE OREGON AND SOUTHERN WASHINGTON CASCADES AND CENTRAL OREGON WHERE A LAL OF 4 IS EXPECTED. AREAS EAST OF THE BLUE MOUNTAINS AND NORTH OF MOUNT ADAMS WILL SEE THUNDERSTORMS DEVELOP LATER IN THE EVENING. THE HRRR MODEL HAS BEEN CONSISTENTLY DEPICTING AN OUTFLOW BOUNDARY OVER CENTRAL OREGON MOVING NORTH TOWARDS THE WASHINGTON COLUMBIA BASIN THIS EVENING. DUE TO CONCERNS ABOUT THE POTENTIAL FOR THIS OUTFLOW BOUNDARY TO DEVELOP AND POSSIBLY REGENERATE THUNDERSTORMS ALONG ITS PATH...I EXTENDED THE WARNING TO INCLUDE ALL OF OUR WASHINGTON COLUMBIA BASIN ZONES. THOSE BATTLING THE SOUTHEAST BENTON COMPLEX FIRE SHOULD BE PREPARED FOR SUDDEN AND ERRATIC WIND GUSTS THIS EVENING. POST FRONTAL WINDS THIS EVENING AND ON MONDAY WILL BE AROUND 10-20 MPH FOR MOST OF THE AREA (20-30 MPH IN THE EASTERN COLUMBIA RIVER GORGE AND THE KITTITAS VALLEY). ANY NEW FIRE STARTS WILL HAVE THE POTENTIAL FOR RAPID SPREAD AS WINDS INCREASE. WISTER && .PRELIMINARY POINT TEMPS/POPS... PDT 72 98 66 97 / 40 20 10 0 ALW 78 99 71 98 / 30 20 10 0 PSC 76 103 66 101 / 30 20 10 0 YKM 77 97 66 97 / 30 20 10 0 HRI 75 101 64 100 / 40 20 10 0 ELN 74 94 65 96 / 30 20 10 0 RDM 61 94 54 95 / 50 10 10 10 LGD 68 93 58 92 / 30 30 20 10 GCD 63 96 56 97 / 30 20 20 10 DLS 73 96 66 98 / 50 20 10 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING FOR ORZ610-611-639- 640. RED FLAG WARNING UNTIL 4 PM PDT MONDAY FOR ORZ641-642-644. HEAT ADVISORY UNTIL 10 PM PDT THIS EVENING FOR ORZ049-050-505. RED FLAG WARNING UNTIL 9 PM PDT MONDAY FOR ORZ643-645. HEAT ADVISORY UNTIL 8 PM PDT MONDAY FOR ORZ044-507. WA...RED FLAG WARNING UNTIL 9 PM PDT THIS EVENING FOR WAZ639-681. RED FLAG WARNING UNTIL 9 PM PDT MONDAY FOR WAZ643-645. RED FLAG WARNING UNTIL 8 PM PDT MONDAY FOR WAZ641-675. HEAT ADVISORY UNTIL 8 PM PDT MONDAY FOR WAZ026>029. && FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT... WWW.WEATHER.GOV/PENDLETON $$ 90/97/97/85
AREA FORECAST DISCUSSION
NWS MEDFORD OR
251 PM PDT SAT JUN 27 2015 .DISCUSSION...THE UPPER LOW OFF THE CALIFORNIA COAST IS PUMPING MOISTURE NORTH TOWARDS THE FORECAST AREA. THE LATEST SPC ANALYSIS SHOWS SURFACE CAPE VALUES NEAR 1500 J/KG IN NORTHERN JACKSON AND A GOOD PORTION OF DOUGLAS AND JOSEPHINE COUNTY WITH LIFTED INDICIES CLOSE TO -4. THE INSTABILITY IS THERE, BUT SO FAR NO TRIGGER. HENCE WHY WE HAVE NOT SEE ANY ACTION SO FAR. HOWEVER THE LATEST HRRR REFLECTIVITY MODELS IS SHOWING RETURNS DEVELOPING AND INCREASING OVER A GOOD PORTION OF THE AREA LATE THIS AFTERNOON FROM ABOUT EASTERN JOSEPHINE COUNTY AND CENTRAL DOUGLAS COUNTY EAST. THIS MODEL ACTUALLY PERFORMED FAIRLY WELL WITH THE PLACEMENT OF ISOLATED STORMS YESTERDAY AFTERNOON AND EVENING. THEREFORE WE EXPECT STORMS TO DEVELOP THIS AFTERNOON AS TEMPERATURES HEAT UP AND WEAK SHORTWAVES MOVE IN FROM THE SOUTH (PER THE RAP SOLUTION). THE WEAK SHORTWAVES WILL PROVIDE THE TRIGGER FOR STORMS TO DEVELOP AND INCREASE AS THE AFTERNOON PROGRESSES. THE VISIBLE IMAGE IS ALREADY SHOWING CU STARTING TO DEVELOP. IT WILL BE HOT AGAIN TODAY, BUT THE ONLY THING THAT COULD LIMIT THE AMOUNT OF HEATING RESULTING IN SLIGHTLY LOWER TEMPERATURES WILL BE CLOUD COVER. THE MODELS HAVE COME INTO BETTER AGREEMENT FOR TONIGHT INTO SUNDAY MORNING. AS THE UPPER LOW MOVES NORTH ALONG THE CALIFORNIA COAST TONIGHT, IT WILL BRING ANOTHER SURGE OF MID LEVEL MOISTURE AND SHORTWAVES MOVING INTO SOUTHWEST OREGON. AT THE SAME TIME 850 LI`S WILL GET INTO THE NEGATIVE TERRITORY. SO THERE IS CONCERN WE COULD SEE ANOTHER ROUND OF NOCTURNAL STORMS IN PARTS OF JOSEPHINE...JACKSON...CURRY...COOS AND DOUGLAS COUNTY...CASCADES AND SISKIYOUS TONIGHT INTO SUNDAY MORNING. THEREFORE HAVE INCREASED POPS IN THESE AREAS. PWATS WILL ALSO INCREASE AND MODEL SOUNDINGS SHOW THE LOWER LEVELS MOISTENING UP. SO THERE IS A CHANCE A FEW OF THESE STORMS COULD PRODUCE SOME RAINFALL. HOWEVER TYPICALLY WHEN WE GET NOCTURNAL STORMS, THEY NORMALLY PRODUCE LITTLE OR NO RAINFALL. OF NOTE THE 700-500MB WIND SPEED IS EXPECTED TO BE BETWEEN 25-30 KTS, SO THEY WILL BE FASTER MOVING. THE MODELS ARE IN FAIRLY GOOD AGREEMENT, BUT HAVE TRENDED SLOWER WITH THE TIMING OF THE UPPER LOW/TROUGH AXIS. IT WILL STILL BE TO OUR SOUTH SUNDAY WITH MID LEVEL DRYING NOT ARRIVING IN SOUTHWEST OREGON AND WESTERN SISKIYOU COUNTY UNTIL SUNDAY EVENING...THEREFORE WE COULD BE LOOKING AT ANOTHER ACTIVE DAY WITH SLOW IMPROVEMENT IN THE ABOVE MENTIONED AREAS UNTIL SUNDAY NIGHT AT WHICH POINT THE FOCUS FOR THUNDERSTORMS WILL SHIFT EAST WITH THE BEST CHANCE FOR STORMS ALONG AND EAST OF THE CASCADES. TEMPERATURES SUNDAY WILL END UP COOLER, MAINLY AS A RESULT OF CLOUD COVER. THE TROUGH AXIS WILL MOVE INTO THE AREA MONDAY MORNING AND THE FOCUS FOR THUNDERSTORMS WILL SHRINK AND BE MAINLY CONFINED TO KLAMATH AND LAKE COUNTY. IT LOOKS LIKE WE COULD CATCH A BREAK IN THE ACTION TUESDAY AS WE GET A MORE STABLE SOUTHWEST FLOW. HOWEVER THE MODELS SHOW MID LEVEL MOISTURE AND INSTABILITY INCREASING IN THE SOUTHEAST PART OF THE CWA, SO LEFT IN A SLIGHT CHANCE OF THUNDERSTORMS. MEANWHILE STABLE ONSHORE FLOW SETS UP WEST OF THE CASCADES AND WE`LL HAVE SLIGHTLY COOLER TEMPERATURES, BUT STILL ABOVE NORMAL FOR INTERIOR LOCATIONS. THE MODELS SHOW THE RIDGE RE BUILDING WESTWARD BEYOND TUESDAY WITH HOT TEMPERATURES RETURNING WITH TRIPLE DIGIT VALUES LIKELY AGAIN FOR MANY WEST SIDE VALLEYS IN OREGON AND NORTHERN CAL. HOWEVER THE PATTERN IS DIFFERENT FROM THE ONE WERE EXPERIENCING NOW. FOR ONE THE HIGHEST MID LEVEL MOISTURE AND INSTABILITY SHOULD BE MOSTLY ALONG AND EAST OF THE CASCADES. HOWEVER THERE`S SOME INDICATIONS WE COULD SEE ANOTHER SURGE OF MONSOONAL MOISTURE MOVE INTO THE AREA TOWARDS THE END OF NEXT WEEK, THUS INCREASING THE CHANCE FOR THUNDERSTORMS OVER A GOOD PORTION OF THE CWA ONCE AGAIN. STAY TUNED. -PETRUCELLI && .AVIATION...FOR THE 27/18Z TAF CYCLE...VFR CONDITIONS WILL CONTINUE INTO THIS EVENING AT THE COAST...THEN MARINE STRATUS RETURNS WITH IFR CIGS EXPECTED BETWEEN 2-3Z AND LASTING INTO SUNDAY MORNING. ELSEWHERE VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS. THE MAIN CONCERN WILL BE ISOLATED TO SCATTERED THUNDERSTORMS LATE THIS AFTERNOON AND POSSIBLY LASTING INTO TONIGHT. GUSTY OUTFLOW WINDS WILL ACCOMPANY STRONGER CELLS. && .MARINE...UPDATED 300 AM PDT SATURDAY 27 JUNE 2015...WINDS AND SEAS WILL GRADUALLY LOWER THIS MORNING THEN REMAIN LOW THROUGH THE REMAINDER OF THE WEEKEND. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS MORNING MAINLY WITHIN 10 NM FROM SHORE. A THERMAL TROUGH WILL STRENGTHEN MONDAY AND PERSIST THROUGH WEDNESDAY WITH SMALL CRAFT NORTH WINDS AND STEEP SEAS REDEVELOPING. SPILDE && .FIRE WEATHER...UPDATED 245 PM PDT SATURDAY 27 JUNE 2015...WITH CLEARING SKIES AND AFTERNOON HEATING ISOLATED THUNDERSTORMS SHOULD DEVELOP AGAIN BY LATE AFTERNOON. PROFILES OVER THE EAST SIDE ARE STILL VERY DRY IN THE SUB-CLOUD LAYER WITH CLOUD BASES AROUND 17- 20KFT, SO STORMS THAT FORM THERE WILL LIKELY STILL BE DRY. MODELS ARE INDICATING ANOTHER STRONGER SHORT WAVE ARRIVING FROM THE SOUTH THIS EVENING ALONG WITH A SUBSTANTIAL INCREASE IN MID-LEVEL MOISTURE. EXPECT BETTER COVERAGE OF STORMS THIS EVENING THROUGH SUNDAY EVENING. WHILE THE MAJORITY OF THE ACTIVITY WILL LIKELY BE ALONG THE SISKIYOUS, UP ALONG THE CASCADES, AND OVER TO THE EAST SIDE...WITH INCREASING SOUTH-SOUTHEAST MID-LEVEL FLOW EXPECT SOME STORMS TO BE ABLE TO MOVE OUT OVER THE VALLEYS OF THE WEST SIDE TOO. SINCE THERE WILL BE AN INCREASE IN MOISTURE, STORMS WILL LIKELY BE WETTER TONIGHT INTO SUNDAY. THE FLOW WILL BEGIN TO TURN MORE SOUTHWESTERLY SUNDAY AS THE UPPER TROUGH OFFSHORE FINALLY BEGINS TO MOVE NORTHEASTWARD...KEEPING SCATTERED THUNDERSTORM COVERAGE FROM THE CASCADE FOOTHILLS TO THE EAST SIDE. && .MFR WATCHES/WARNINGS/ADVISORIES... OR... RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR ORZ616-617-619>625. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ023. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ024-026. CA...RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR CAZ280-281-284-285. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR CAZ080-081. PACIFIC COASTAL WATERS...NONE. $$
AREA FORECAST DISCUSSION
NWS MEDFORD OR
925 AM PDT SAT JUN 27 2015 .DISCUSSION...CURRENT VISIBLE IMAGE SHOWS PLENTY OF INSTABILITY CLOUDS MOVING NORTH OVER PARTS OF THE AREA. HOWEVER THERE IS CLEARING JUST SOUTH OF THE AREA AND THIS WILL BE MOVING NORTH DURING THE COURSE OF THE DAY. THE TEMPERATURE AT MEDFORD IS ALREADY 81 DEGREES WITH A DEWPOINT OF 59. IN FACT DEWPOINTS ARE HIGHER OVER MOST LOCATIONS, SO THERE IS MORE JUICE COMPARED TO YESTERDAY. ALSO THE SOUNDING THIS MORNING SHOWS PW VALUE OF 1.31 INCHES WITH A FAIRLY MOST LAYER FROM AROUND 550 TO 330 MB. THE CURRENT RUN OF THE HRRR 1KM REFLECTIVITY SHOWS INCREASING RETURNS LATE THIS MORNING INTO THIS AFTERNOON WITH THE BULK OF THE RETURNS CENTERED FROM KLAMATH COUNTY INTO EASTERN JACKSON AND NORTH INTO DOUGLAS COUNTY. SO FAR THE RADAR IS SHOWING LIGHT RETURNS IN DOUGLAS COUNTY, BUT THIS IS SOMETHING WE`LL HAVE TO KEEP A CLOSE EYE ON DURING THE COURSE OF THE MORNING AND AFTERNOON. OF NOTE LOOKING AT THE SPC MESOSCALE ANALYSIS SHOWS CAPE VALUES INCREASING OVER SOUTHWEST OREGON IN THE PAST 3 HOURS WITH LITTLE OR NO CHANGE IN CIN VALUES. ALSO SURFACE BASED LI`S ARE -4 C IN SOUTHWEST OREGON AND SURFACE CAPE VALUES ARE JUST OVER 1000 J/KG AND CLEARING WILL DEVELOP THERE IN THE NEXT FEW HOURS. ONLY MADE A FEW MINOR ADJUSTMENTS TO THE FORECAST. MOSTLY WITH THE TIMING OF CONVECTION, OTHERWISE THE THINKING MENTIONED IN THE PREVIOUS DISCUSSION IS STILL VALID. -PETRUCELLI && .AVIATION...FOR THE 27/12Z TAF CYCLE...AREAS OF IFR CIGS/VIS ALONG THE COAST THIS MORNING WILL GIVE WAY TO VFR. ISOLATED SHOWERS AND THUNDERSTORMS IN COOS/DOUGLAS COUNTIES WILL LIFT NORTH OF THE AREA BY LATE THIS MORNING. VFR WILL PREVAIL ELSEWHERE. LATER THIS AFTERNOON THROUGH TONIGHT...ISOLATED TO SCATTERED THUNDERSTORMS WILL DEVELOP ACROSS THE AREA. GUSTY OUTFLOW WINDS WILL ACCOMPANY STRONGER CELLS. IFR CIGS PROBABLY RETURN TO THE NORTH COAST THIS EVENING AND LAST THROUGH THE NIGHT. SPILDE && .MARINE...UPDATED 300 AM PDT SATURDAY 27 JUNE 2015...WINDS AND SEAS WILL GRADUALLY LOWER THIS MORNING THEN REMAIN LOW THROUGH THE REMAINDER OF THE WEEKEND. ISOLATED THUNDERSTORMS ARE POSSIBLE THIS MORNING MAINLY WITHIN 10 NM FROM SHORE. A THERMAL TROUGH WILL STRENGTHEN MONDAY AND PERSIST THROUGH WEDNESDAY WITH SMALL CRAFT NORTH WINDS AND STEEP SEAS REDEVELOPING. SPILDE && .FIRE WEATHER...UPDATED 300 AM PDT SATURDAY 27 JUNE 2015...A SHORT WAVE OFFSHORE WILL LIFT NORTH THIS MORNING. THERE CAN STILL BE ISOLATED THUNDERSTORMS ALONG THE COAST THIS MORNING, BUT THESE SHOULD MOVE AWAY BY THIS AFTERNOON. MEANWHILE, THERE WILL PROBABLY BE A BIT OF A BREAK ELSEWHERE THIS MORNING AS THE ATMOSPHERE IS GOING TO HAVE TO TAKE SOME TIME TO RE-LOAD. THERE SHOULD BE ENOUGH SUNSHINE FOR STRONG HEATING IN MOST AREAS AGAIN TODAY WITH HIGHS REACHING THE LOWER TO MID 100S IN THE VALLEYS WEST OF THE CASCADES AND IN NORTHERN CALIFORNIA WITH MID TO UPPER 90S OVER THE EAST SIDE. ISOLATED THUNDERSTORMS SHOULD DEVELOP AGAIN DURING THE MID AND LATE AFTERNOON. PROFILES OVER THE EAST SIDE ARE STILL VERY DRY IN THE SUB- CLOUD LAYER WITH CLOUD BASES AROUND 17-20KFT, SO STORMS THAT FORM THERE WILL LIKELY STILL BE DRY. MODELS ARE INDICATING ANOTHER STRONGER SHORT WAVE ARRIVING FROM THE SOUTH THIS EVENING ALONG WITH A SUBSTANTIAL INCREASE IN MID-LEVEL MOISTURE. EXPECT BETTER COVERAGE OF STORMS THIS EVENING THROUGH SUNDAY EVENING. WHILE THE MAJORITY OF THE ACTIVITY WILL LIKELY BE ALONG THE SISKIYOUS, UP ALONG THE CASCADES, AND OVER TO THE EAST SIDE...WITH INCREASING SOUTH-SOUTHEAST MID-LEVEL FLOW EXPECT SOME STORMS TO BE ABLE TO MOVE OUT OVER THE VALLEYS OF THE WEST SIDE TOO. SINCE THERE WILL BE AN INCREASE IN MOISTURE, STORMS WILL LIKELY BE WETTER TONIGHT INTO SUNDAY. THE FLOW WILL BEGIN TO TURN MORE SOUTHWESTERLY SUNDAY AS THE UPPER TROUGH OFFSHORE FINALLY BEGINS TO MOVE NORTHEASTWARD. IT MAY TAKE ALL DAY TO DO THIS, SO THE HEADLINES FOR THE WEST SIDE MAY NEED TO BE EXTENDED INTO AT LEAST THE AFTERNOON, IF NOT EARLY EVENING. WE`LL MAINTAIN THE HEADLINES AS IS THOUGH FOR NOW AND ALLOW THE DAY SHIFT TO TAKE ANOTHER LOOK. SPILDE && .PREV DISCUSSION... /ISSUED 337 AM PDT SAT JUN 27 2015/ DISCUSSION...STRONG HIGH PRESSURE OVER THE GREAT BASIN AND A LOW PRESSURE OFF THE CALIFORNIA COAST ARE THE MAJOR PLAYERS IN OUR UNSETTLED PATTERN OVER THE NEXT FEW DAYS. THE STRONG HIGH PRESSURE IS RESPONSIBLE FOR THE RECORD HEAT YESTERDAY. MEDFORD SET A NEW RECORD OF 107, MOUNT SHASTA CITY 99...KLAMATH FALLS 98...ALTURAS WITH 101...AND MONTAGUE TIED WITH 104. THIS HIGH PRESSURE COUPLED WITH THE LOW PRESSURE OFF THE COAST ARE FEEDING SOUTHERLY MOISTURE INTO THE AREA. THE MOISTURE COMBINED WITH THE INSTABILITY FROM DAYTIME HEATING AND SHORTWAVES EMBEDDED IN THE SOUTHERLY FLOW RESULTED IN THUNDERSTORMS OVER THE AREA YESTERDAY AFTERNOON. THERE WAS ABOUT 250 LIGHTNING STRIKES...CONCENTRATED OVER THE CASCADES AND NORTHERN KLAMATH COUNTY. WITH THE EXCEPTION OF A FEW STRIKES HERE AND THERE, THUNDERSTORMS HAVE SUBSIDED AND A FEW SHOWERS ARE CURRENTLY MOVING THROUGH DOUGLAS AND COOS COUNTIES. EXPECT MUCH OF THE SAME TODAY...HOT TEMPERATURES WITH AFTERNOON/EVENING THUNDERSTORMS. ORIGINAL THINKING WAS THAT CONVECTION WILL BE MORE WIDESPREAD TODAY SO WITH THE INCREASE IN CLOUD COVER, TEMPERATURES SHOULD BE A FEW DEGREES COOLER. STILL EXPECTING AN INCREASE IN CONVECTION, HOWEVER THE MODELS ARE HOLDING OFF ON SHORTWAVE TO KICK OFF THIS CONVECTION UNTIL LATER THIS AFTERNOON/EARLY EVENING. THIS COULD MEAN LESS CLOUDS AND MORE SUN FILTERING THROUGH WITH TEMPERATURES WARMER THAN FORECASTED. ON THE OTHER HAND, MODELS ARE INDICATING HIGH LEVEL CLOUDS LINGERING OVER THE AREA THROUGH THE AFTERNOON SO THIS MAY BE ENOUGH TO KEEP TEMPERATURES DOWN A BIT. EITHER WAY, IT WILL STILL BE HOT, SO STUCK WITH THE ORIGINAL IDEA AND ONLY TWEAKED TEMPERATURES SOME. AS FAR AS THUNDERSTORMS GO FOR TODAY...THE LACK OF A SHORTWAVE UNTIL THIS LATER AFTERNOON...POSSIBLY LATE EVENING...COULD MEAN THAT THUNDERSTORMS WON`T KICK UP UNTIL THEN. GIVEN THE UNSTABLE AIR MASS IN PLACE, ONCE THE SHORTWAVE ARRIVES, THUNDERSTORMS WILL HAVE PLENTY OF ENERGY TO TAP INTO. THERE WILL ALSO BE MORE MOISTURE INVOLVED SO THUNDERSTORMS ARE MORE LIKELY TO BE WET. THERE ARE STILL SOME SOUNDING PROFILES ON THE EAST SIDE SHOWING THE INVERTED-V SIGNATURE WITH CLOUD BASES AROUND 17KFT. THIS INDICATES THAT THESE STORMS WILL LIKELY BE DRY AND HAVE THE POTENTIAL STRONG GUSTY OUTFLOW WINDS. GIVEN THE POSSIBLE LATER START TO CONVECTION TODAY, NOCTURNAL THUNDERSTORMS ARE STILL EXPECTED THROUGH TONIGHT. EMBEDDED SHORTWAVES WILL LIKELY KEEP THE CONVECTION GOING INTO SUNDAY MORNING AND AFTERNOON AS THE UPPER TROUGH NUDGES CLOSER TO THE OREGON COAST. THE UPPER TROUGH SWINGS THROUGH LATE SUNDAY INTO MONDAY...COOLING TEMPERATURES SOME AND PUSHING THE FOCUS OF CONVECTION TO EAST OF THE CASCADES. WHILE TEMPERATURES WILL "COOL", THEY WILL STILL BE ABOVE NORMAL...BY ABOUT 10 DEGREES...COMPARED TO 15 TO 20 DEGREES ABOVE NORMAL ON FRIDAY. THIS "COOLING" WILL BE SHORT LIVED AS THE HIGH PRESSURE OVER THE GREAT BASIN BUILDS BACK OVER THE AREA. TEMPERATURES WILL AGAIN RISE ABOVE THE CENTURY MARK FOR WEST SIDE VALLEYS AND RETURN TO THE UPPER 90`S EAST OF THE CASCADES BY TUESDAY. -MND && .MFR WATCHES/WARNINGS/ADVISORIES... OR... RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR ORZ615>625. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ023. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR ORZ024-026. CA...RED FLAG WARNING UNTIL 11 PM PDT SUNDAY FOR CAZ280-281-284-285. HEAT ADVISORY UNTIL 5 AM PDT SUNDAY FOR CAZ080-081. PACIFIC COASTAL WATERS...NONE. $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
558 PM EDT SAT JUN 27 2015 .SYNOPSIS... AN UNSEASONABLY STRONG AREA OF LOW PRESSURE OVER NORTHERN OHIO THIS AFTERNOON...ALONG WITH ITS ATTENDANT FRONTAL SYSTEM...WILL CONTINUE TO BRING PERIODS OF HEAVY RAIN...ACROSS MAINLY THE EASTERN HALF OF THE STATE LATE TODAY INTO EARLY TONIGHT. THE HEAVY RAINFALL COMBINED WITH VERY WET PRE- EXISTING CONDITIONS OVER THE LAST 30 DAYS WILL RESULT IN AN ELEVATED RISK FOR FLOODING ALONG SMALLER STREAMS AND CREEKS INTO TONIGHT. A FLOOD WATCH REMAINS IN EFFECT INTO EARLY SUNDAY MORNING. SEVERE WEATHER IS ALSO POSSIBLE ACROSS FAR SOUTH-CENTRAL PENNSYLVANIA LATE THIS AFTERNOON INTO EARLY TONIGHT. UNSEASONABLY COOL AND SHOWERY WEATHER WILL CONTINUE SUNDAY...THOUGH MOST OF THE SHOWERS WILL OCCUR ACROSS THE MOUNTAINS OF NORTHERN AND WESTERN PENN. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 2 PM UPDATE... THE SHIELD OF STEADY MDT TO HVY RAIN WILL CONTINUE TO MOVE NE AND BECOME BE CONFINED ACROSS THE NE HALF OF PENN LATE TODAY AND THIS EVENING...WITH CLOUDY SKIES AND MORE SHOWERY CONDITIONS PERSISTING ELSEWHERE AS THE MAIN AXIS OF STRONG /NEARLY 5 SIGMA/ LLVL SERLY WINDS SHIFT TO THE POCONOS OF NEPA. AN APPROX 4-5 HOUR WINDOW /FROM 21Z TDY - 02Z SUN/ OF SEVERE TSRA POTENTIAL ISOLATED WIND GUSTS AROUND 60 KT...AND PERHAPS A BRIEF TORNADO...WILL OCCUR ACROSS THE SOUTHERN LAYER OF PENN COUNTIES /MAINLY SOMERSET COUNTY/ AND POINTS EAST OF INTERSTATE 81...WHERE 12Z OPER MODELS AND HOURLY RUNS OF HRRR INDICATE THE OVERLAP OF SEVERAL HUNDRED J/KG OF SREF CAPE WITH THE DEPARTING HIGHLY ANOMALOUS LLJ. TORNADO WATCH 364 RECENTLY ISSUED ACROSS PARTS OF THE MIDDLE ATL PIEDMONT AND VA COASTAL PLAIN ALONG AND JUST SOUTH OF THE SLOWLY ADVANCING WARM FRONT. WOULD/T BE SURPRISED TO SEE A SECOND WATCH ISSUED FOR PORTIONS OF FAR SCENT AND SERN PENN IN A FEW HOURS...AS THE NORTHERN PART OF THE NOSE OF LOW CAPE/HIGH SHEAR MOVES INTO THAT AREA. SATURATED GROUND AND GUSTY SERLY GRADIENT WIND /30-40 MPH ON THE RIDGES/ HAS ALREADY CAUSED SPORADIC DOWNED TREES. ANY STRONGER TSRA WITH TORRENTIAL RAINS IN SOUTHERN PENN WILL ONLY ADD TO THIS ISSUE. SKIES WILL STAY CLOUDY OVERNIGHT WITH OCNL SHOWERS...BECOMING SCATTERED AFTER MIDNIGHT...WITH AREAS OF DRIZZLE AND MUCH LIGHTER/VARIABLE WIND AS THE CENTER OF LOW PRESSURE/OCCLUDED FRONT DRIFTS ENE ACROSS PENN. LOW TEMPS TONIGHT WILL VARY FROM THE L50S NORTH...TO THE LOW 60S SOUTH. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... SOME PCPN WILL LINGER ON SUNDAY ON THE BACKSIDE OF THE DEPARTING SYNOPTIC SCALE LOW...ESPECIALLY IN THE UPSLOPE REGIONS/HIGHER TERRAIN OF THE ALLEGHENIES WHERE A NORTH/SOUTH AREA OF ENHANCED MID LEVEL LAPSE RATES WILL BE LOCATED DURING THE AFTERNOON HOURS. QPF AMTS WILL BE ON THE LIGHT SIDE WITH LITTLE TO NO PCPN EXPECTED BY SUNDAY NIGHT AS DRIER AIR MOVES INTO THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL WITH USUALLY COLDER AREAS ALONG THE ALLEGHENY FRONT STRUGGLING TO CRACK 60F. HIGHS IN THE LOWER SUSQ WILL REACH 70-75F. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THE UPPER LEVEL LOW THAT HAS BEEN BRINGING THE PRECIPITOUS WEATHER WILL CONTINUE TO MOVE EASTWARD...ROTATING AROUND A STRONGER CLOSED LOW SITUATED OVER HUDSON BAY. THESE SYSTEMS HAVE BEEN MODERATED BY A LARGE RIDGE THAT HAS BEEN PARKED OVER THE CENTRAL GREAT BASIN AND PACIFIC NORTHWEST. THAT RIDGE WILL BEGIN TO BREAK DOWN EARLY NEXT WEEK...AND A SERIES OF MID- LEVEL DISTURBANCES WILL EMANATE FROM THE QUASI-STATIONARY UPPER LEVEL LOW OVER THE HUDSON BAY. HOWEVER AS THESE TROUGHS ARE SHALLOWER...LESS MOISTURE SHOULD BE ASSOCIATED WITH THEM AND THEY SHOULD BE WEAKER ACCORDINGLY. NONETHELESS...THIS SERIES OF PERTERBATIONS WILL PROLONG THE PERSISTENT UNSETTLED/WET PATTERN THAT WE HAVE BEEN IN FOR THE LAST 30 DAYS OR SO. TEMPERATURES WILL START OUT WELL BELOW NORMAL ON SUNDAY BEFORE TRENDING BACK TO NORMAL THROUGH THE MIDDLE OF NEXT WEEK. && .AVIATION /22Z SATURDAY THROUGH THURSDAY/... WIDESPREAD IFR WITH AREAS MVFR CONDITIONS WHAT HAS NOW TRANSITIONED INTO SHOWERY PRECIPITATION ACROSS CENTRAL PENNSYLVANIA. LOW PRESSURE NEAR CLEVELAND WILL TRACK EAST ACROSS CENTRAL PENNSYLVANIA TONIGHT...AND DRAG ITS ASSOCIATED TRAILING COLD/OCCLUDED FRONT ACROSS THE REGION OVERNIGHT. WHILE CONDITIONS HAVE IMPROVED OVER THE LAST 3 HOURS...CONDITIONS SHOULD ONCE AGAIN DETERIORATE FURTHER TO IFR-LIFR LATE TONIGHT /ESPECIALLY AT KBFD AND KJST/ AS COOLER AIR MOVES INTO THE REGION...COMBINED WITH THE MOIST AIRMASS AND LIGHT WINDS. LOW LEVEL SE FLOW OF 40-50 KTS IN THE 2-3KFT AGL LAYER WILL LEAD TO LLWS THROUGH EARLY TONIGHT AT ALL TAF SITES. OUTLOOK... SUN...RESTRICTIONS MAINLY NW HALF OF PA. SCT SHOWERS. MON-THU...GENERALLY VFR...BUT CHANCE OF MVFR IN SHOWERS MAINLY ACROSS THE NW HALF OF PENN TUESDAY AFTERNOON AND NIGHT. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 2 AM EDT SUNDAY FOR PAZ004>006-010>012- 017>019-024>028-033>037-041-042-045-046-049>053-056>059- 063>066. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT/STEINBUGL LONG TERM...CERU/STEINBUGL AVIATION...JUNG/LAMBERT
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
357 PM EDT SAT JUN 27 2015 .SYNOPSIS... AN UNSEASONABLY STRONG AREA OF LOW PRESSURE OVER NORTHERN OHIO THIS AFTERNOON...ALONG WITH ITS ATTENDANT FRONTAL SYSTEM...WILL CONTINUE TO BRING PERIODS OF HEAVY RAIN...ACROSS MAINLY THE EASTERN HALF OF THE STATE LATE TODAY INTO EARLY TONIGHT. THE HEAVY RAINFALL COMBINED WITH VERY WET PRE- EXISTING CONDITIONS OVER THE LAST 30 DAYS WILL RESULT IN AN ELEVATED RISK FOR FLOODING ALONG SMALLER STREAMS AND CREEKS INTO TONIGHT. A FLOOD WATCH REMAINS IN EFFECT INTO EARLY SUNDAY MORNING. SEVERE WEATHER IS ALSO POSSIBLE ACROSS FAR SOUTH-CENTRAL PENNSYLVANIA LATE THIS AFTERNOON INTO EARLY TONIGHT. UNSEASONABLY COOL AND SHOWERY WEATHER WILL CONTINUE SUNDAY...THOUGH MOST OF THE SHOWERS WILL OCCUR ACROSS THE MOUNTAINS OF NORTHERN AND WESTERN PENN. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... 2 PM UPDATE... THE SHIELD OF STEADY MDT TO HVY RAIN WILL CONTINUE TO MOVE NE AND BECOME BE CONFINED ACROSS THE NE HALF OF PENN LATE TODAY AND THIS EVENING...WITH CLOUDY SKIES AND MORE SHOWERY CONDITIONS PERSISTING ELSEWHERE AS THE MAIN AXIS OF STRONG /NEARLY 5 SIGMA/ LLVL SERLY WINDS SHIFT TO THE POCONOS OF NEPA. AN APPROX 4-5 HOUR WINDOW /FROM 21Z TDY - 02Z SUN/ OF SEVERE TSRA POTENTIAL ISOLATED WIND GUSTS AROUND 60 KT...AND PERHAPS A BRIEF TORNADO...WILL OCCUR ACROSS THE SOUTHERN LAYER OF PENN COUNTIES /MAINLY SOMERSET COUNTY/ AND POINTS EAST OF INTERSTATE 81...WHERE 12Z OPER MODELS AND HOURLY RUNS OF HRRR INDICATE THE OVERLAP OF SEVERAL HUNDRED J/KG OF SREF CAPE WITH THE DEPARTING HIGHLY ANOMALOUS LLJ. TORNADO WATCH 364 RECENTLY ISSUED ACROSS PARTS OF THE MIDDLE ATL PIEDMONT AND VA COASTAL PLAIN ALONG AND JUST SOUTH OF THE SLOWLY ADVANCING WARM FRONT. WOULD/T BE SURPRISED TO SEE A SECOND WATCH ISSUED FOR PORTIONS OF FAR SCENT AND SERN PENN IN A FEW HOURS...AS THE NORTHERN PART OF THE NOSE OF LOW CAPE/HIGH SHEAR MOVES INTO THAT AREA. SATURATED GROUND AND GUSTY SERLY GRADIENT WIND /30-40 MPH ON THE RIDGES/ HAS ALREADY CAUSED SPORADIC DOWNED TREES. ANY STRONGER TSRA WITH TORRENTIAL RAINS IN SOUTHERN PENN WILL ONLY ADD TO THIS ISSUE. SKIES WILL STAY CLOUDY OVERNIGHT WITH OCNL SHOWERS...BECOMING SCATTERED AFTER MIDNIGHT...WITH AREAS OF DRIZZLE AND MUCH LIGHTER/VARIABLE WIND AS THE CENTER OF LOW PRESSURE/OCCLUDED FRONT DRIFTS ENE ACROSS PENN. LOW TEMPS TONIGHT WILL VARY FROM THE L50S NORTH...TO THE LOW 60S SOUTH. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/... SOME PCPN WILL LINGER ON SUNDAY ON THE BACKSIDE OF THE DEPARTING SYNOPTIC SCALE LOW...ESPECIALLY IN THE UPSLOPE REGIONS/HIGHER TERRAIN OF THE ALLEGHENIES WHERE A NORTH/SOUTH AREA OF ENHANCED MID LEVEL LAPSE RATES WILL BE LOCATED DURING THE AFTERNOON HOURS. QPF AMTS WILL BE ON THE LIGHT SIDE WITH LITTLE TO NO PCPN EXPECTED BY SUNDAY NIGHT AS DRIER AIR MOVES INTO THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL WITH USUALLY COLDER AREAS ALONG THE ALLEGHENY FRONT STRUGGLING TO CRACK 60F. HIGHS IN THE LOWER SUSQ WILL REACH 70-75F. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THE UPPER LEVEL LOW THAT HAS BEEN BRINGING THE PRECIPITOUS WEATHER WILL CONTINUE TO MOVE EASTWARD...ROTATING AROUND A STRONGER CLOSED LOW SITUATED OVER HUDSON BAY. THESE SYSTEMS HAVE BEEN MODERATED BY A LARGE RIDGE THAT HAS BEEN PARKED OVER THE CENTRAL GREAT BASIN AND PACIFIC NORTHWEST. THAT RIDGE WILL BEGIN TO BREAK DOWN EARLY NEXT WEEK...AND A SERIES OF MID- LEVEL DISTURBANCES WILL EMANATE FROM THE QUASI-STATIONARY UPPER LEVEL LOW OVER THE HUDSON BAY. HOWEVER AS THESE TROUGHS ARE SHALLOWER...LESS MOISTURE SHOULD BE ASSOCIATED WITH THEM AND THEY SHOULD BE WEAKER ACCORDINGLY. NONETHELESS...THIS SERIES OF PERTERBATIONS WILL PROLONG THE PERSISTENT UNSETTLED/WET PATTERN THAT WE HAVE BEEN IN FOR THE LAST 30 DAYS OR SO. TEMPERATURES WILL START OUT WELL BELOW NORMAL ON SUNDAY BEFORE TRENDING BACK TO NORMAL THROUGH THE MIDDLE OF NEXT WEEK. && .AVIATION /20Z SATURDAY THROUGH THURSDAY/... EXPECT WIDESPREAD IFR/LIFR CONDITIONS IN MODERATE TO HEAVY RAIN THROUGH THE REST OF THE AFTERNOON/EARLY EVENING ACROSS THE SUSQ VALLEY AND NCENT MTNS...WHILE THE SCENT AND CENTRAL MTNS SEE VSBYS AND CIGS LIFT A BIT TO MVFR OR IFR IN MORE SHOWERY CONDITIONS. LOW PRESSURE OVER NRN OHIO WILL MOVE EAST NEAR THE I-80 CORRIDOR TONIGHT...AND ITS SWD TRAILING COLD/OCCLUDED FRONT WILL BEGIN TO SWING IN FROM THE SOUTHWEST TOWARD 00Z SUNDAY. WHILE THERE MAY BE THIS BRIEF UPTICK IN CONDITIONS BETWEEN 21Z SAT-01Z SUN...CONDITIONS SHOULD ONCE AGAIN DETERIORATE FURTHER TO IFR-LIFR LATE TONIGHT /ESPECIALLY AT KBFD AND KJST/ AS COOLER AIR MOVES INTO THE REGION...COMBINED WITH THE MOIST AIRMASS AND LIGHT WINDS. LOW LEVEL SE FLOW OF 40-50 KTS IN THE 2-3KFT AGL LAYER WILL LEAD TO LLWS THROUGH EARLY TONIGHT AT ALL TAF SITES. OUTLOOK... SUN...RESTRICTIONS MAINLY NW HALF OF PA. SCT SHOWERS. MON-THU...GENERALLY VFR...BUT CHANCE OF MVFR IN SHOWERS MAINLY ACROSS THE NW HALF OF PENN TUESDAY AFTERNOON AND NIGHT. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 2 AM EDT SUNDAY FOR PAZ004>006-010>012- 017>019-024>028-033>037-041-042-045-046-049>053-056>059- 063>066. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT/STEINBUGL LONG TERM...CERU/STEINBUGL AVIATION...LAMBERT/GARTNER
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
259 PM EDT SAT JUN 27 2015 .SYNOPSIS... AN UNSEASONABLY STRONG AREA OF LOW PRESSURE OVER NORTHERN OHIO THIS AFTERNOON...ALONG WITH ITS ATTENDANT FRONTAL SYSTEM...WILL CONTINUE TO BRING PERIODS OF HEAVY RAIN...ACROSS MAINLY THE EASTERN HALF OF THE STATE LATE TODAY INTO EARLY TONIGHT. THE HEAVY RAINFALL COMBINED WITH VERY WET PRE- EXISTING CONDITIONS OVER THE LAST 30 DAYS WILL RESULT IN AN ELEVATED RISK FOR FLOODING ALONG SMALLER STREAMS AND CREEKS INTO TONIGHT. A FLOOD WATCH REMAINS IN EFFECT INTO EARLY SUNDAY MORNING. SEVERE WEATHER IS ALSO POSSIBLE ACROSS FAR SOUTH-CENTRAL PENNSYLVANIA LATE THIS AFTERNOON INTO EARLY TONIGHT. UNSEASONABLY COOL AND SHOWERY WEATHER WILL CONTINUE SUNDAY...THOUGH MOST OF THE SHOWERS WILL OCCUR ACROSS THE MOUNTAINS OF NORTHERN AND WESTERN PENN. && .NEAR TERM /THROUGH TONIGHT/... 2 PM UPDATE... THE SHIELD OF STEADY MDT TO HVY RAIN WILL CONTINUE TO MOVE NE AND BECOME BE CONFINED ACROSS THE NE HALF OF PENN LATE TODAY AND THIS EVENING...WITH CLOUDY SKIES AND MORE SHOWERY CONDITIONS PERSISTING ELSEWHERE AS THE MAIN AXIS OF STRONG /NEARLY 5 SIGMA/ LLVL SERLY WINDS SHIFT TO THE POCONOS OF NEPA. AN APPROX 4-5 HOUR WINDOW /FROM 21Z TDY - 02Z SUN/ OF SEVERE TSRA POTENTIAL ISOLATED WIND GUSTS AROUND 60 KT...AND PERHAPS A BRIEF TORNADO...WILL OCCUR ACROSS THE SOUTHERN LAYER OF PENN COUNTIES /MAINLY SOMERSET COUNTY/ AND POINTS EAST OF INTERSTATE 81...WHERE 12Z OPER MODELS AND HOURLY RUNS OF HRRR INDICATE THE OVERLAP OF SEVERAL HUNDRED J/KG OF SREF CAPE WITH THE DEPARTING HIGHLY ANOMALOUS LLJ. TORNADO WATCH 364 RECENTLY ISSUED ACROSS PARTS OF THE MIDDLE ATL PIEDMONT AND VA COASTAL PLAIN ALONG AND JUST SOUTH OF THE SLOWLY ADVANCING WARM FRONT. WOULD/T BE SURPRISED TO SEE A SECOND WATCH ISSUED FOR PORTIONS OF FAR SCENT AND SERN PENN IN A FEW HOURS...AS THE NORTHERN PART OF THE NOSE OF LOW CAPE/HIGH SHEAR MOVES INTO THAT AREA. SATURATED GROUND AND GUSTY SERLY GRADIENT WIND /30-40 MPH ON THE RIDGES/ HAS ALREADY CAUSED SPORADIC DOWNED TREES. ANY STRONGER TSRA WITH TORRENTIAL RAINS IN SOUTHERN PENN WILL ONLY ADD TO THIS ISSUE. SKIES WILL STAY CLOUDY OVERNIGHT WITH OCNL SHOWERS...BECOMING SCATTERED AFTER MIDNIGHT...WITH AREAS OF DRIZZLE AND MUCH LIGHTER/VARIABLE WIND AS THE CENTER OF LOW PRESSURE/OCCLUDED FRONT DRIFTS ENE ACROSS PENN. LOW TEMPS TONIGHT WILL VARY FROM THE L50S NORTH...TO THE LOW 60S SOUTH. && .SHORT TERM /SUNDAY/... SOME PCPN WILL LINGER ON SUNDAY ON THE BACKSIDE OF THE DEPARTING SYNOPTIC SCALE LOW...ESPECIALLY IN THE UPSLOPE REGIONS/HIGHER TERRAIN OF THE ALLEGHENIES WHERE A NORTH/SOUTH AREA OF ENHANCED MID LEVEL LAPSE RATES WILL BE LOCATED DURING THE AFTERNOON HOURS. QPF AMTS WILL BE ON THE LIGHT SIDE WITH LITTLE TO NO PCPN EXPECTED BY SUNDAY NIGHT AS DRIER AIR MOVES INTO THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL WITH USUALLY COLDER AREAS ALONG THE ALLEGHENY FRONT STRUGGLING TO CRACK 60F. HIGHS IN THE LOWER SUSQ WILL REACH 70-75F. && .LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/... THE BROAD TROUGH WILL CONTINUE TO LINGER WELL INTO NEXT WEEK DOWNSTREAM OF A MIGRATORY AND ANOMALOUS UPPER-LEVEL ANTICYCLONE PARKED OVER THE CENTRAL GREAT BASIN AND PACIFIC NORTHWEST. A SERIES OF MID-LEVEL DISTURBANCES WILL TRANSLATE SOUTHEAST FROM THE HOT UPPER RIDGE THROUGH THE NORTHERN PLAINS...UPPER MIDWEST/OH VALLEY AND INTO THE MID ATLANTIC STATES...WITH EACH WAVE AND ACCOMPANYING WEAK FRONTAL SYSTEM PROVIDING A FOCUS FOR SHOWERS AND THUNDERSTORMS. THESE NRN STREAM SYSTEMS WILL PACK MUCH LESS OF A PUNCH COMPARED TO THE UNSEASONABLY STRONG SYSTEM IMPACTING THE AREA THIS WEEKEND...BUT NONETHELESS IT WILL PROLONG THE PERSISTENT UNSETTLED/WET PATTERN THAT WE HAVE BEEN IN FOR THE LAST 30 DAYS OR SO. TEMPERATURES WILL START OUT WELL BELOW NORMAL ON SUNDAY BEFORE TRENDING BACK TO NORMAL THROUGH THE MIDDLE OF NEXT WEEK. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... EXPECT WIDESPREAD IFR/LIFR CONDITIONS IN MODERATE TO HEAVY RAIN THROUGH THE REST OF THE AFTERNOON/EARLY EVENING ACROSS THE SUSQ VALLEY AND NCENT MTNS...WHILE THE SCENT AND CENTRAL MTNS SEE VSBYS AND CIGS LIFT A BIT TO MVFR OR IFR IN MORE SHOWERY CONDITIONS. LOW PRESSURE OVER NRN OHIO WILL MOVE EAST NEAR THE I-80 CORRIDOR TONIGHT...AND ITS SWD TRAILING COLD/OCCLUDED FRONT WILL BEGIN TO SWING IN FROM THE SOUTHWEST TOWARD 00Z SUNDAY. WHILE THERE MAY BE THIS BRIEF UPTICK IN CONDITIONS BETWEEN 21Z SAT-01Z SUN...CONDITIONS SHOULD ONCE AGAIN DETERIORATE FURTHER TO IFR-LIFR LATE TONIGHT /ESPECIALLY AT KBFD AND KJST/ AS COOLER AIR MOVES INTO THE REGION...COMBINED WITH THE MOIST AIRMASS AND LIGHT WINDS. LOW LEVEL SE FLOW OF 40-50 KTS IN THE 2-3KFT AGL LAYER WILL LEAD TO LLWS THROUGH EARLY TONIGHT AT ALL TAF SITES. OUTLOOK... SUN...RESTRICTIONS MAINLY NW HALF OF PA. SCT SHOWERS. MON-THU...GENERALLY VFR...BUT CHANCE OF MVFR IN SHOWERS MAINLY ACROSS THE NW HALF OF PENN TUESDAY AFTERNOON AND NIGHT. && .CTP WATCHES/WARNINGS/ADVISORIES... FLOOD WATCH UNTIL 2 AM EDT SUNDAY FOR PAZ004>006-010>012- 017>019-024>028-033>037-041-042-045-046-049>053-056>059- 063>066. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT/STEINBUGL LONG TERM...STEINBUGL AVIATION...LAMBERT
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
804 PM CDT SUN JUN 28 2015 .UPDATE... ONLY MINOR UPDATE MADE TO THE FORECAST TONIGHT WAS TO BRING SLIGHT CHANCE POPS SLIGHLY FURTHER SOUTH AFTER MIDNIGHT. THIS IS LARGELY BASED ON HI-RES GUIDANCE MAINTAINING THE COMPLEX MOVING SOUTH OUT OF MISSOURI. OTHERWISE...FORECAST LOOKS GOOD AND NO OTHER CHANGES WERE MADE. && .PREV DISCUSSION... /ISSUED 304 PM CDT SUN JUN 28 2015/ DISCUSSION... SKIES ARE MOSTLY SUNNY ACROSS MUCH OF THE FORECAST AREA THIS AFTERNOON WITH TEMPERATURES IN THE 80S. A COLD FRONT CURRENTLY EXTENDS FROM CENTRAL IOWA THROUGH NORTHWEST MISSOURI AND INTO CENTRAL KANSAS. THE FRONT WILL PUSH INTO SOUTHERN MISSOURI TONIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF THE FRONT TONIGHT AND SOME OF THIS ACTIVITY MAY REACH NORTHERN SECTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE A LITTLE WARMER THAN SATURDAY NIGHT WITH LOWS MONDAY MORNING FROM THE MID 60S TO AROUND 70 DEGREES. THE COLD FRONT WILL MOVE CLOSER TO THE FORECAST AREA ON MONDAY WITH ISOLATED THUNDERSTORMS POSSIBLE OVER NORTHERN SECTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE CLOSER TO NORMAL LEVELS WITH HIGHS IN THE UPPER 80S TO LOWER 90S. BY MONDAY NIGHT THE COLD FRONT WILL MOVE INTO THE REGION AND STALL OUT SO THERE WILL BE A BETTER CHANCE OF THUNDERSTORMS ACROSS THE ENTIRE FORECAST AREA FOR BOTH MONDAY NIGHT AND TUESDAY. BY TUESDAY NIGHT...THE COLD FRONT STARTS TO FALL APART BUT AN UPPER LEVEL DISTURBANCE WILL PUSH THROUGH MISSOURI SO THERE WILL BE A SMALL CHANCE OF THUNDERSTORMS FOR TUESDAY NIGHT AND A BETTER CHANCE FOR WEDNESDAY. TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL WITH HIGHS ON WEDNESDAY MAINLY IN THE 80S. THE UPPER LEVEL DISTURBANCE WILL MOVE THROUGH WEST TENNESSEE WEDNESDAY NIGHT SO THERE WILL STILL BE A CHANCE OF THUNDERSTORMS. UNSETTLED WEATHER WILL CONTINUE FOR THURSDAY THROUGH NEXT SUNDAY AS A FRONTAL BOUNDARY REMAINS NORTH OF THE FORECAST AREA DURING THE PERIOD. ADDITIONAL UPPER LEVEL DISTURBANCES WILL MOVE THROUGH THE REGION AS WELL. THESE TWO FACTORS WILL HELP KEEP A CHANCE OF THUNDERSTORMS DURING THIS PERIOD. TEMPERATURES WILL REMAIN NEAR OR SLIGHTLY BELOW NORMAL. ARS .AVIATION... 00Z TAF CYCLE (29/00Z-30/00Z) VFR CONDITIONS WILL OCCUR THROUGH THE PERIOD. WINDS WILL REMAIN SOUTHERLY AT 6-10 KTS TONIGHT FOR KMEM... KMKL... AND KJBR. A DISTURBANCE CURRENTLY NW OF THE REGION WILL MOVE THROUGH THE REGION OVERNIGHT BUT THE EFFECTS WILL BE MINIMAL WITH ONLY INCREASED CLOUDINESS AND A CHANCE OF SCATTERED SHOWERS MAINLY FOR KMKL. ADDED VCSH AT 6Z FOR KMKL DUE TO THE LATEST HRRR MODEL RUN. WINDS TOMORROW WILL INCREASE THROUGH THE DAY FROM THE SOUTH. JPM3 && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
634 PM CDT SUN JUN 28 2015 .UPDATE... && .DISCUSSION... && .PREV DISCUSSION... /ISSUED 304 PM CDT SUN JUN 28 2015/ DISCUSSION... SKIES ARE MOSTLY SUNNY ACROSS MUCH OF THE FORECAST AREA THIS AFTERNOON WITH TEMPERATURES IN THE 80S. A COLD FRONT CURRENTLY EXTENDS FROM CENTRAL IOWA THROUGH NORTHWEST MISSOURI AND INTO CENTRAL KANSAS. THE FRONT WILL PUSH INTO SOUTHERN MISSOURI TONIGHT. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP AHEAD OF THE FRONT TONIGHT AND SOME OF THIS ACTIVITY MAY REACH NORTHERN SECTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE A LITTLE WARMER THAN SATURDAY NIGHT WITH LOWS MONDAY MORNING FROM THE MID 60S TO AROUND 70 DEGREES. THE COLD FRONT WILL MOVE CLOSER TO THE FORECAST AREA ON MONDAY WITH ISOLATED THUNDERSTORMS POSSIBLE OVER NORTHERN SECTIONS OF THE FORECAST AREA. TEMPERATURES WILL BE CLOSER TO NORMAL LEVELS WITH HIGHS IN THE UPPER 80S TO LOWER 90S. BY MONDAY NIGHT THE COLD FRONT WILL MOVE INTO THE REGION AND STALL OUT SO THERE WILL BE A BETTER CHANCE OF THUNDERSTORMS ACROSS THE ENTIRE FORECAST AREA FOR BOTH MONDAY NIGHT AND TUESDAY. BY TUESDAY NIGHT...THE COLD FRONT STARTS TO FALL APART BUT AN UPPER LEVEL DISTURBANCE WILL PUSH THROUGH MISSOURI SO THERE WILL BE A SMALL CHANCE OF THUNDERSTORMS FOR TUESDAY NIGHT AND A BETTER CHANCE FOR WEDNESDAY. TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL WITH HIGHS ON WEDNESDAY MAINLY IN THE 80S. THE UPPER LEVEL DISTURBANCE WILL MOVE THROUGH WEST TENNESSEE WEDNESDAY NIGHT SO THERE WILL STILL BE A CHANCE OF THUNDERSTORMS. UNSETTLED WEATHER WILL CONTINUE FOR THURSDAY THROUGH NEXT SUNDAY AS A FRONTAL BOUNDARY REMAINS NORTH OF THE FORECAST AREA DURING THE PERIOD. ADDITIONAL UPPER LEVEL DISTURBANCES WILL MOVE THROUGH THE REGION AS WELL. THESE TWO FACTORS WILL HELP KEEP A CHANCE OF THUNDERSTORMS DURING THIS PERIOD. TEMPERATURES WILL REMAIN NEAR OR SLIGHTLY BELOW NORMAL. ARS .AVIATION... 00Z TAF CYCLE (29/00Z-30/00Z) VFR CONDITIONS WILL OCCUR THROUGH THE PERIOD. WINDS WILL REMAIN SOUTHERLY AT 6-10 KTS TONIGHT FOR KMEM... KMKL... AND KJBR. A DISTURBANCE CURRENTLY NW OF THE REGION WILL MOVE THROUGH THE REGION OVERNIGHT BUT THE EFFECTS WILL BE MINIMAL WITH ONLY INCREASED CLOUDINESS AND A CHANCE OF SCATTERED SHOWERS MAINLY FOR KMKL. ADDED VCSH AT 6Z FOR KMKL DUE TO THE LATEST HRRR MODEL RUN. WINDS TOMORROW WILL INCREASE THROUGH THE DAY FROM THE SOUTH. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MORRISTOWN TN
313 AM EDT SAT JUN 27 2015 .SHORT TERM (TODAY AND TONIGHT)... LOW PRESSURE WILL BE TRACKING NE ACROSS OH WITH A TRAILING COLD FRONT CROSSING TN THROUGH THE DAY. THE HRRR APPEARS TO HAVE A DECENT GRASP ON THE CURRENT CONVECTION OVER SOUTHERN MIDDLE TN...AND SHOWS THIS AREA MOVING NE ACROSS OUR AREA FROM 10Z TO 16Z. ALTHOUGH INSTABILITY IS WEAK OVER THE AREA TODAY WITH MLCAPE GENERALLY LESS THAN 1000 J/KG...SOME ENHANCEMENT OF CONVECTION WILL BE POSSIBLE LATE THIS MORNING INTO THE EARLY AFTERNOON AS THE UPPER JET MOVES INTO KY AND PROVIDES SOME UPPER DIVERGENCE...AND A PRE-FRONTAL TROUGH PROVIDES SOME SURFACE CONVERGENCE. THE SEVERE THREAT...MAINLY WIND...LOOKS LOW BUT CANNOT BE RULED OUT...WITH THE BEST CHANCES IN THE NORTHERN HALF OF THE CWA. THE COLD FRONT MOVES INTO THE AREA LATE THIS AFTERNOON...AND EXITS A LITTLE AFTER SUNSET. RAPID MIDLEVEL DRYING WILL END ALL PRECIP CHANCES AROUND MIDNIGHT...WITH LOW CLOUDS CLEARING OUT SOON AFTER. .LONG TERM (TOMORROW THROUGH SATURDAY)... THE DRY WEATHER WILL CONTINUE BEHIND THE FRONT THROUGH THE WEEKEND INTO MONDAY BEFORE RAIN CHANCES INCREASE. A SECONDARY TROUGH FORMS BEHIND THE QUICKLY EXITING LOW, AND BRINGS WITH IT ANOTHER FRONTAL BOUNDARY. THIS ONE DOESN`T LOOK TO AFFECT TEMPERATURES VERY MUCH, BUT WILL HELP FOCUS SHOWER AND THUNDERSTORM ACTIVITY INTO MID-WEEK. THEN OUR SECOND SYSTEM NEXT WEEK WILL BE A LOW MOVING SOUTHEAST OUT OF THE NORTHERN PLAINS STATES. CURRENT TRACK OF THIS SYSTEM IS DIFFICULT TO DETERMINE AT THIS POINT AS MODELS HAVE A WIDE RANGE OF POSSIBILITIES. WHEREVER THIS SYSTEM DECIDES TO TRACK NEAR WILL BE IN FOR A VERY GOOD CHANCE AT WIDESPREAD RAINFALL LATE IN THE WORK WEEK HEADING INTO THE WEEKEND. CURRENTLY AT THIS TIME, NO DAYS JUMP OUT AS HAVING A WIDESPREAD SEVERE THREAT... BUT AGAIN MODEL DIFFERENCE MAKES THE LONG TERM PORTION OF THE FORECAST DIFFICULT. ONE THREAT THAT WE WILL NEED TO KEEP MONITORING WILL BE THE CHANCE FOR ANY FLOODING LATE IN THE WEEK IF THESE FIRST COUPLE OF SYSTEMS BRING WIDESPREAD HEAVY RAIN TO THE AREA. OVERALL THE TEMPERATURES LOOK TO REMAIN AT, OR JUST BELOW, NORMAL THROUGH THE END OF THE 7-DAY FORECAST. && .PRELIMINARY POINT TEMPS/POPS... CHATTANOOGA AIRPORT, TN 81 63 87 62 / 90 10 0 10 KNOXVILLE MCGHEE TYSON AIRPORT, TN 79 60 82 60 / 90 20 0 10 OAK RIDGE, TN 78 59 84 58 / 90 10 0 10 TRI CITIES AIRPORT, TN 80 58 80 54 / 90 40 10 10 && .MRX WATCHES/WARNINGS/ADVISORIES... NC...NONE. TN...NONE. VA...NONE. && $$ DGS/ABM
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1256 PM CDT SAT JUN 27 2015 .AVIATION... THE MAIN CONCERN THIS AFTERNOON IS AN APPROACHING FRONTAL BOUNDARY. THE FRONT EXTENDS FROM A LOW NEAR SWEETWATER. A WARM FRONT EXTENDS TO THE EAST AND A COLD FRONT TO THE SOUTH INTO VAL VERDE COUNTY. THIS FRONT WILL BRING SHOWERS AND THUNDERSTORMS TO THE TERMINALS THIS AFTERNOON OR EVENING. DRT WILL SEE SOME SHRA OVER THE NEXT COUPLE OF HOURS...BUT THESE SHOULD BE LIGHT AND NOT AFFECT CIGS/VIS. LATER THIS EVENING MORE TSRA WILL MOVE THROUGH DROPPING CONDITIONS TO MVFR OCCASIONALLY. THE FRONT SHOULD BE THROUGH AND ALL CONVECTION ENDED BY AROUND 06Z. THEN MVFR CIGS WILL FORM IN AUSTIN AND SAN ANTONIO. CONDITIONS THERE SHOULD IMPROVE LATE MORNING SUNDAY. && .PREV DISCUSSION... /ISSUED 949 AM CDT SAT JUN 27 2015/ UPDATE... ONLY MINOR CHANGES MADE TO THE ONGOING FORECAST. RETRENDED THE HOURLY WEATHER GRIDS. ALSO EDITED POPS SLIGHTLY DROPPING CHANCES FOR THE REST OF THE MORNING BY ABOUT 10% DUE TO DECREASED COVERAGE AND MOST OF THE SHOWER AND THUNDERSTORM ACTIVITY REMAINING TO OUR NORTH. HAVE MOVED THE FOCUS OF AFTERNOON PRECIPITATION A BIT FARTHER SOUTH THAN THE PREVIOUS FORECAST BASED ON HIGH RESOLUTION MODELS...AND EXTENDED LIKELY POPS TO THE RIO GRANDE RIVER DUE TO THE PRESENCE OF A MESO LOW/CIRCULATION THAT CAN BE SEEN ON RADAR OVER VAL VERDE COUNTY. THIS MAY ENHANCE AFTERNOON RAIN CHANCES THERE. DISCUSSION... THE FRONT THAT HAS BEEN TALKED ABOUT THE LAST FEW DAYS IS SLOWLY INCHING SOUTHWARD ACROSS TEXAS. IT IS CURRENTLY LOCATED ALONG AN OZONA TO ABILENE TO GAINESVILLE LINE TO THE NORTH OF OUR AREA. IT ALREADY KICKED OFF THE MORNING CONVECTION OVER OUR AREA WITH MORE STORMS BEGINNING TO DEVELOP BETWEEN SAN ANGELO AND WACO. MOST OF THE MORNING PRECIPITATION HAS ENDED WITH POCKETS OF SHOWERS AND A THUNDERSTORM OR TWO REMAINING. THE HRRR AND NSSL WRF BOTH SHOW MORE SHOWERS AND THUNDERSTORMS FORMING THIS AFTERNOON ACROSS SOUTH CENTRAL TEXAS DUE TO THE PRESENCE OF THE FRONT AND INCREASED HEATING. DECENT RAIN CHANCES RUN THROUGH THIS AFTERNOON AND TONIGHT. SOME POCKETS OF LOCALLY HEAVY RAINFALL AND STRONG STORMS PRODUCING BRIEF GUSTY WINDS WILL BE POSSIBLE. PREV DISCUSSION... /ISSUED 300 AM CDT SAT JUN 27 2015/ SHORT TERM (TODAY THROUGH SUNDAY)... CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY DROPPING SOUTH ACROSS CENTRAL TEXAS. THESE WILL MOVE INTO THE HILL COUNTRY AND EDWARDS PLATEAU EARLY THIS MORNING LEAVING SURFACE BOUNDARIES. AN UPPER LEVEL RIDGE OVER THE WESTERN STATES AND AN UPPER LEVEL TROUGH OVER THE EASTERN STATES FORCE A WEAK COLD FRONT INTO SOUTH CENTRAL TEXAS TODAY. THE FRONT STALLS TONIGHT ACROSS SOUTH CENTRAL TEXAS AND THEN SLOWLY DISSIPATES AS IT MOVES BACK TO THE NORTH ON SUNDAY. THE FRONT AND BOUNDARIES PROVIDE UPWARD FORCING FOR SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE AREA TODAY. LEFT OVER BOUNDARIES AND THE FRONT ALLOW SHOWERS AND THUNDERSTORMS TO CONTINUE TONIGHT INTO SUNDAY. PWS AROUND 2 INCHES AND SLOW STORM MOTIONS CONTINUE A THREAT OF LOCALLY HEAVY RAINS WITH SOME MINOR FLOODING POSSIBLE WHERE STORMS TRAIN OVER THE SAME AREAS. CAPES NEAR 2000 J/KG INDICATE SOME STRONG TO MARGINALLY SEVERE WIND GUSTS ARE ALSO POSSIBLE. LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)... THE WESTERN RIDGE AND EASTERN TROUGH PATTERN SLOWLY DEAMPLIFIES DURING THE WEEK. AN INVERTED TROUGH FROM MEXICO INTO SOUTHERN TEXAS DEVELOPS EARLY IN THE WEEK TO MAINTAIN CHANCES OF SHOWERS AND THUNDERSTORMS MONDAY THROUGH WEDNESDAY WITH GREATER COVERAGE DURING THE DAYLIGHT HOURS DUE TO AN ENHANCED SEABREEZE. THE INVERTED TROUGH MOVES TO THE WEST LATE IN THE WEEK AS AN UPPER LEVEL RIDGE OVER THE GULF OF MEXICO TRIES TO CONNECT WITH THE RIDGE IN THE WEST. EARLIER MODEL RUNS WERE IN GOOD AGREEMENT THIS WOULD HAPPEN. HOWEVER...THE MOST RECENT RUN OF THE ECMWF GOES BACK TO BEING SLOWER ON THE WESTWARD MOVEMENT OF THE INVERTED TROUGH. HAVE EXTENDED SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS WEST TO THE I-35 CORRIDOR FOR THURSDAY AND FRIDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 72 89 72 90 72 / 60 30 10 30 20 AUSTIN BERGSTROM INTL AIRPORT 71 89 71 90 71 / 50 30 10 30 20 NEW BRAUNFELS MUNI AIRPORT 72 89 72 89 72 / 60 40 20 30 20 BURNET MUNI AIRPORT 70 89 70 89 70 / 40 10 10 20 10 DEL RIO INTL AIRPORT 73 91 73 93 74 / 40 30 10 10 10 GEORGETOWN MUNI AIRPORT 71 89 71 90 71 / 30 20 10 30 20 HONDO MUNI AIRPORT 72 89 71 90 72 / 60 30 20 20 20 SAN MARCOS MUNI AIRPORT 72 89 72 89 72 / 60 40 20 30 20 LA GRANGE - FAYETTE REGIONAL 73 89 73 89 73 / 60 50 30 40 20 SAN ANTONIO INTL AIRPORT 74 89 73 90 73 / 60 50 20 30 20 STINSON MUNI AIRPORT 74 90 73 90 73 / 60 40 20 20 20 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...05 SYNOPTIC/GRIDS...TREADWAY PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
949 AM CDT SAT JUN 27 2015 .UPDATE... ONLY MINOR CHANGES MADE TO THE ONGOING FORECAST. RETRENDED THE HOURLY WEATHER GRIDS. ALSO EDITED POPS SLIGHTLY DROPPING CHANCES FOR THE REST OF THE MORNING BY ABOUT 10% DUE TO DECREASED COVERAGE AND MOST OF THE SHOWER AND THUNDERSTORM ACTIVITY REMAINING TO OUR NORTH. HAVE MOVED THE FOCUS OF AFTERNOON PRECIPITATION A BIT FARTHER SOUTH THAN THE PREVIOUS FORECAST BASED ON HIGH RESOLUTION MODELS...AND EXTENDED LIKELY POPS TO THE RIO GRANDE RIVER DUE TO THE PRESENCE OF A MESO LOW/CIRCULATION THAT CAN BE SEEN ON RADAR OVER VAL VERDE COUNTY. THIS MAY ENHANCE AFTERNOON RAIN CHANCES THERE. && .DISCUSSION... THE FRONT THAT HAS BEEN TALKED ABOUT THE LAST FEW DAYS IS SLOWLY INCHING SOUTHWARD ACROSS TEXAS. IT IS CURRENTLY LOCATED ALONG AN OZONA TO ABILENE TO GAINESVILLE LINE TO THE NORTH OF OUR AREA. IT ALREADY KICKED OFF THE MORNING CONVECTION OVER OUR AREA WITH MORE STORMS BEGINNING TO DEVELOP BETWEEN SAN ANGELO AND WACO. MOST OF THE MORNING PRECIPITATION HAS ENDED WITH POCKETS OF SHOWERS AND A THUNDERSTORM OR TWO REMAINING. THE HRRR AND NSSL WRF BOTH SHOW MORE SHOWERS AND THUNDERSTORMS FORMING THIS AFTERNOON ACROSS SOUTH CENTRAL TEXAS DUE TO THE PRESENCE OF THE FRONT AND INCREASED HEATING. DECENT RAIN CHANCES RUN THROUGH THIS AFTERNOON AND TONIGHT. SOME POCKETS OF LOCALLY HEAVY RAINFALL AND STRONG STORMS PRODUCING BRIEF GUSTY WINDS WILL BE POSSIBLE. && .PREV DISCUSSION... /ISSUED 609 AM CDT SAT JUN 27 2015/ AVIATION... BROKEN LINE OF CONVECTION IS SLOWLY MOVING SOUTH...BUT IS SLIGHTLY AHEAD OF SCHEDULE WITH ACTIVITY ALREADY IMPACTING KDRT. WILL BUMP UP THE BEGINNING OF VCTS AND TEMPO -TSRA FOR THE AUSTIN AND SAN ANTONIO SITES 2-3 HOURS. WILL ONLY INCLUDE A 4 HOUR TEMPO GROUP IMMEDIATELY AFTER THE ONSET OF CONVECTION CHANCES...BUT THIS MAY NEED TO BE AMENDED LATER IN THE DAY AS SCATTERED CONVECTION CONTINUES THROUGH TONIGHT. OTHERWISE...POSSIBLE MVFR CONDITIONS ARE EXPECTED THIS MORNING AND THEN ONCE AGAIN TONIGHT. PREV DISCUSSION... /ISSUED 300 AM CDT SAT JUN 27 2015/ SHORT TERM (TODAY THROUGH SUNDAY)... CLUSTERS OF SHOWERS AND THUNDERSTORMS ARE CURRENTLY DROPPING SOUTH ACROSS CENTRAL TEXAS. THESE WILL MOVE INTO THE HILL COUNTRY AND EDWARDS PLATEAU EARLY THIS MORNING LEAVING SURFACE BOUNDARIES. AN UPPER LEVEL RIDGE OVER THE WESTERN STATES AND AN UPPER LEVEL TROUGH OVER THE EASTERN STATES FORCE A WEAK COLD FRONT INTO SOUTH CENTRAL TEXAS TODAY. THE FRONT STALLS TONIGHT ACROSS SOUTH CENTRAL TEXAS AND THEN SLOWLY DISSIPATES AS IT MOVES BACK TO THE NORTH ON SUNDAY. THE FRONT AND BOUNDARIES PROVIDE UPWARD FORCING FOR SHOWERS AND THUNDERSTORMS TO DEVELOP ACROSS THE AREA TODAY. LEFT OVER BOUNDARIES AND THE FRONT ALLOW SHOWERS AND THUNDERSTORMS TO CONTINUE TONIGHT INTO SUNDAY. PWS AROUND 2 INCHES AND SLOW STORM MOTIONS CONTINUE A THREAT OF LOCALLY HEAVY RAINS WITH SOME MINOR FLOODING POSSIBLE WHERE STORMS TRAIN OVER THE SAME AREAS. CAPES NEAR 2000 J/KG INDICATE SOME STRONG TO MARGINALLY SEVERE WIND GUSTS ARE ALSO POSSIBLE. LONG TERM (SUNDAY NIGHT THROUGH FRIDAY)... THE WESTERN RIDGE AND EASTERN TROUGH PATTERN SLOWLY DEAMPLIFIES DURING THE WEEK. AN INVERTED TROUGH FROM MEXICO INTO SOUTHERN TEXAS DEVELOPS EARLY IN THE WEEK TO MAINTAIN CHANCES OF SHOWERS AND THUNDERSTORMS MONDAY THROUGH WEDNESDAY WITH GREATER COVERAGE DURING THE DAYLIGHT HOURS DUE TO AN ENHANCED SEABREEZE. THE INVERTED TROUGH MOVES TO THE WEST LATE IN THE WEEK AS AN UPPER LEVEL RIDGE OVER THE GULF OF MEXICO TRIES TO CONNECT WITH THE RIDGE IN THE WEST. EARLIER MODEL RUNS WERE IN GOOD AGREEMENT THIS WOULD HAPPEN. HOWEVER...THE MOST RECENT RUN OF THE ECMWF GOES BACK TO BEING SLOWER ON THE WESTWARD MOVEMENT OF THE INVERTED TROUGH. HAVE EXTENDED SLIGHT CHANCES OF SHOWERS AND THUNDERSTORMS WEST TO THE I-35 CORRIDOR FOR THURSDAY AND FRIDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 89 72 90 71 91 / 60 50 30 10 20 AUSTIN BERGSTROM INTL AIRPORT 89 71 89 71 91 / 60 50 30 10 30 NEW BRAUNFELS MUNI AIRPORT 90 72 89 72 91 / 60 50 40 20 30 BURNET MUNI AIRPORT 88 71 89 70 91 / 50 40 10 10 20 DEL RIO INTL AIRPORT 92 73 92 73 94 / 60 40 20 10 10 GEORGETOWN MUNI AIRPORT 87 71 89 71 91 / 60 30 20 10 20 HONDO MUNI AIRPORT 89 72 89 71 90 / 50 50 30 20 20 SAN MARCOS MUNI AIRPORT 88 72 89 72 90 / 60 50 40 20 30 LA GRANGE - FAYETTE REGIONAL 87 73 89 73 90 / 50 50 40 20 30 SAN ANTONIO INTL AIRPORT 90 74 89 73 91 / 60 50 40 20 30 STINSON MUNI AIRPORT 91 73 90 73 91 / 50 50 40 20 20 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...05 SYNOPTIC/GRIDS...TREADWAY PUBLIC SERVICE/DATA COLLECTION...33
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
150 PM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH SUNDAY/... AS OF 1255 PM EDT SATURDAY... ACROSS THE REGION KFCX 88D RADAR CONTINUE TO SHOW TWO AREAS WHERE PRECIPITATION THE NEXT FEW HOURS WILL BE THE MOST PLENTIFUL. SOME PATCHY LIGHT TO MODERATE RAIN WAS SPREADING NORTHEAST OUT OF TENNESSEE/KENTUCKY INTO OUR REGION. THE BULK OF THIS ACTIVITY WILL BE ALONG AND WEST OF A BOONE NC...BLACKSBURG VA...LEWISBURG WV LINE THROUGH THE MID AFTERNOON. BY THE LATE AFTERNOON...THIS ACTIVITY WILL HAVE REACHED CENTRAL PORTIONS OF THE FORECAST AREA. AS MORE SURFACE HEATING TAKES PLACE...THERE THE TREND WILL BE FOR STRONGER SHOWER AND THUNDERSTORM DEVELOPMENT. THE OTHER REGION OF PRECIPITATION ACTIVITY IS IN THE FORM OF ISOLATED TO SCATTERED SHOWERS AND STORMS THAT ARE FORMING ACROSS EASTERN PARTS OF SOUTHSIDE VIRGINIA...NORTH INTO THE JAMES RIVER BASIN. THIS ACTIVITY IS EXPECTED TO CONTINUE WITHIN THIS REGION...AND ALSO EXPAND IN COVERAGE. IN BETWEEN THESE TWO AREAS...VERY LITTLE IN THE WAY OF PRECIPITATIONS WAS OCCURRING. WHILE THIS WILL CONTINUE TO BE THE TREND...THERE ALSO WILL BE TREND FOR FOR MORE DEVELOPMENT THAN THE CURRENT SCENARIO. HAVE MADE APPROPRIATE CHANGES TO THE POP AND WEATHER GRIDS TO REFLECT THESE THREE AREAS AND EXPECTED TRENDS THROUGH THE REMAINDER OF THE AFTERNOON. NO CHANGES TO THE HIGH TEMPERATURE FORECAST...BUT HAVE ADJUSTED HOURLY TEMPERATURES TO BETTER FIT THE CURRENT CONDITIONS AND EXPECTED TRENDS. AS OF 955 AM EDT SATURDAY... OUR FORECAST UPDATE THIS MORNING REFLECT AN ADJUSTMENT TO THE PLACEMENT AND TIMING OF PRECIPITATION ACROSS...OR EXPECTED TO MOVE INTO THE REGION. LITTLE IF ANY PRECIPITATION IS CURRENTLY FALLING ACROSS THE REGION...ALTHOUGH A GENEROUS AREA HAS JUST EXITED THE NORTH...AND ANOTHER REGION IS ABOUT TO ENTER FROM THE SOUTHWEST. THE UPDATE WILL REFLECT A LULL IN THE ACTIVITY...ESPECIALLY IN THE EAST...UNTIL ADDITIONAL PRECIPITATION CAN PROGRESS INTO THE AREA FROM THE SOUTHWEST...OR DEVELOP ACROSS THE AREA AS WE HEAD INTO THE AFTERNOON. NO OTHER NOTABLE CHANGES AT THIS TIME. AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 145 PM EDT SATURDAY... THE AREA REMAINS IN THE MOIST AND PROGRESSIVELY UNSTABLE AIR IN ADVANCE OF AN APPROACHING COLD FRONT. CIGS RANGE FROM HIGH END MVFR TO LOW END VFR...AND THAT TREND ALONG WITH PROGRESSIVELY INCREASING SHOWERS AND STORMS IS EXPECTED THE REMAINDER OF THE AFTERNOON. SOME OF THE STRONGER STORMS THAT DEVELOP LATER THIS AFTERNOON MAY CONTAIN VERY GUSTY WINDS AND HAIL. THIS EVENING...A COLD FRONT WILL ACROSS THE AREA. LOOK FOR WINDS TO SHIFT NORTHEAST AND START TO INCREASE. ANTICIPATE A WINTER-LIKE UPSLOPE ENVIRONMENT WITH DECREASING CIGS INTO THE IFR/MVFR RANGE FROM SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA...ALONG WITH SOME ISOLATED TO SCATTERED UPSLOPE RAIN SHOWERS. THE REMAINDER OF THE AREA WILL PROBABLY NOT REALIZE THE SURFACE GUSTS UNTIL DAYBREAK MONDAY...AND ANTICIPATE LESS CLOUD COVER. ON MONDAY...EXPECT A GUSTY DAY...ESPECIALLY ACROSS THE MOUNTAINS AS 850 MB WINDS ARE PROGGED TO BE IN THE 40 TO 50 KT RANGE. ANY DAYBREAK SUB-VFR CONDITIONS WILL TREND TO VFR THROUGH THE MORNING HOURS. EXTENDED AVIATION DISCUSSION... EXPECT MAINLY VFR CONDITIONS SUNDAY AFTERNOON INTO MONDAY AS HIGH PRESSURE SPREADS ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY INTO THURSDAY. && .HYDROLOGY... AS OF 655 AM EDT SATURDAY... A SWATH OF HEAVIER SHOWERS AND THUNDERSTORMS MOVED ACROSS MUCH OF THE REGION OVERNIGHT RESULTING IN SPOTS RECEIVING BETWEEN 1 AND 3 INCHES OF RAIN. THE MOST CONCENTRATED AREA OF HEAVY RAIN WAS ALONG/WEST OF THE BLUE RIDGE ESPECIALLY FROM ASHE COUNTY NORTH ACROSS THE MOUNTAIN EMPIRE REGION INTO SOUTHEAST WEST VIRGINIA AS WELL AS THE VIRGINIA HIGHLANDS. SHOWERS ARE EXPECTED TO REDEVELOP OVER THE MOUNTAINS THIS MORNING AND THEN SPREAD EAST WHILE STRENGTHENING AHEAD OF A STRONG COLD FRONT THAT WILL ARRIVE THIS EVENING. THE POTENTIAL EXISTS FOR LINES OR CLUSTERS OF STORMS TO DEVELOP AND OVER THE MOUNTAINS WHERE FLASH FLOOD GUIDANCE IS NOW LOWEST. RAINFALL OF 1 TO PERHAPS AS MUCH AS 3 INCHES COULD OCCUR WITH VERY HEAVY RAINFALL RATES EXCEEDING 2 INCHES AT HOUR AT TIMES. GIVEN THAT SOME AREAS ARE NOW MORE PRIMED FOR FLOODING THE EARLIER FLASH FLOOD WATCH WAS EXTENDED/EXPANDED THROUGH LATE THIS AFTERNOON FOR MANY COUNTIES ALONG AND WEST OF THE BLUE RIDGE. THIS EXCLUDES PARTS OF THE NEW RIVER VALLEY AND NORTHWEST NORTH CAROLINA WHERE EARLIER RAINFALL WAS NOT AS HEAVY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR VAZ007- 009>015-018>020-022>024-034-035. NC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ001. WV...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...DS NEAR TERM...DS SHORT TERM...RAB LONG TERM...RAB AVIATION...DS HYDROLOGY...JH EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
102 PM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1255 PM EDT SATURDAY... ACROSS THE REGION KFCX 88D RADAR CONTINUE TO SHOW TWO AREAS WHERE PRECIPITATION THE NEXT FEW HOURS WILL BE THE MOST PLENTIFUL. SOME PATCHY LIGHT TO MODERATE RAIN WAS SPREADING NORTHEAST OUT OF TENNESSEE/KENTUCKY INTO OUR REGION. THE BULK OF THIS ACTIVITY WILL BE ALONG AND WEST OF A BOONE NC...BLACKSBURG VA...LEWISBURG WV LINE THROUGH THE MID AFTERNOON. BY THE LATE AFTERNOON...THIS ACTIVITY WILL HAVE REACHED CENTRAL PORTIONS OF THE FORECAST AREA. AS MORE SURFACE HEATING TAKES PLACE...THERE THE TREND WILL BE FOR STRONGER SHOWER AND THUNDERSTORM DEVELOPMENT. THE OTHER REGION OF PRECIPITATION ACTIVITY IS IN THE FORM OF ISOLATED TO SCATTERED SHOWERS AND STORMS THAT ARE FORMING ACROSS EASTERN PARTS OF SOUTHSIDE VIRGINIA...NORTH INTO THE JAMES RIVER BASIN. THIS ACTIVITY IS EXPECTED TO CONTINUE WITHIN THIS REGION...AND ALSO EXPAND IN COVERAGE. IN BETWEEN THESE TWO AREAS...VERY LITTLE IN THE WAY OF PRECIPITATIONS WAS OCCURRING. WHILE THIS WILL CONTINUE TO BE THE TREND...THERE ALSO WILL BE TREND FOR FOR MORE DEVELOPMENT THAN THE CURRENT SCENARIO. HAVE MADE APPROPRIATE CHANGES TO THE POP AND WEATHER GRIDS TO REFLECT THESE THREE AREAS AND EXPECTED TRENDS THROUGH THE REMAINDER OF THE AFTERNOON. NO CHANGES TO THE HIGH TEMPERATURE FORECAST...BUT HAVE ADJUSTED HOURLY TEMPERATURES TO BETTER FIT THE CURRENT CONDITIONS AND EXPECTED TRENDS. AS OF 955 AM EDT SATURDAY... OUR FORECAST UPDATE THIS MORNING REFLECT AN ADJUSTMENT TO THE PLACEMENT AND TIMING OF PRECIPITATION ACROSS...OR EXPECTED TO MOVE INTO THE REGION. LITTLE IF ANY PRECIPITATION IS CURRENTLY FALLING ACROSS THE REGION...ALTHOUGH A GENEROUS AREA HAS JUST EXITED THE NORTH...AND ANOTHER REGION IS ABOUT TO ENTER FROM THE SOUTHWEST. THE UPDATE WILL REFLECT A LULL IN THE ACTIVITY...ESPECIALLY IN THE EAST...UNTIL ADDITIONAL PRECIPITATION CAN PROGRESS INTO THE AREA FROM THE SOUTHWEST...OR DEVELOP ACROSS THE AREA AS WE HEAD INTO THE AFTERNOON. NO OTHER NOTABLE CHANGES AT THIS TIME. AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 705 AM EDT SATURDAY... SHOWERS HAVE REDEVELOPED ACROSS THE FAR WEST THIS MORNING AND EXPECT THESE TO PERSIST AROUND KBLF/KLWB THROUGH AT LEAST MID MORNING RESULTING IN MVFR CIGS AND PERHAPS MVFR VSBYS AT TIMES. SOME OF THESE SHOWERS LIKELY TO MOVE EAST TOWARD KBCB/KROA BEFORE SEEING ADDED REDEVELOPMENT OF STRONGER SHRA/TSRA TAKE SHAPE THIS AFTERNOON. OTRW EVEN WITHOUT SHOWERS...LOOKING AT LOW CONDITIONS OUTSIDE OF KDAN TO INIT WITH WIDESPREAD MVFR/IFR CIGS IN THE WAKE OF THE HEAVIER RAINFALL FROM OVERNIGHT. THINK SHOULD SEE SOME SLOW IMPROVEMENT TO CIGS THROUGH THE MORNING BUT ADDED SHRA MIGHT HOLD AT LEAST MVFR CONDITIONS IN PLACE LONGER SO SLOWED DOWN IMPROVEMENT UNTIL LATE MORNING/EARLY AFTERNOON. OTRW PRIMARY CONCERN THIS AFTERNOON IS WITH THE STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR LATER TODAY INTO THIS EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT LATE TONIGHT. ANTICIPATING ANOTHER BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT LATER THIS AFTERNOON...FOLLOWED BY PARTIAL CLEARING TONIGHT WITH GUSTY WESTERLY WINDS IN ALL EXCEPT THE UPSLOPE AREAS WHERE PERIODS OF MVFR CIGS LIKELY TO LINGER. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION THIS AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .HYDROLOGY... AS OF 655 AM EDT SATURDAY... A SWATH OF HEAVIER SHOWERS AND THUNDERSTORMS MOVED ACROSS MUCH OF THE REGION OVERNIGHT RESULTING IN SPOTS RECEIVING BETWEEN 1 AND 3 INCHES OF RAIN. THE MOST CONCENTRATED AREA OF HEAVY RAIN WAS ALONG/WEST OF THE BLUE RIDGE ESPECIALLY FROM ASHE COUNTY NORTH ACROSS THE MOUNTAIN EMPIRE REGION INTO SOUTHEAST WEST VIRGINIA AS WELL AS THE VIRGINIA HIGHLANDS. SHOWERS ARE EXPECTED TO REDEVELOP OVER THE MOUNTAINS THIS MORNING AND THEN SPREAD EAST WHILE STRENGTHENING AHEAD OF A STRONG COLD FRONT THAT WILL ARRIVE THIS EVENING. THE POTENTIAL EXISTS FOR LINES OR CLUSTERS OF STORMS TO DEVELOP AND OVER THE MOUNTAINS WHERE FLASH FLOOD GUIDANCE IS NOW LOWEST. RAINFALL OF 1 TO PERHAPS AS MUCH AS 3 INCHES COULD OCCUR WITH VERY HEAVY RAINFALL RATES EXCEEDING 2 INCHES AT HOUR AT TIMES. GIVEN THAT SOME AREAS ARE NOW MORE PRIMED FOR FLOODING THE EARLIER FLASH FLOOD WATCH WAS EXTENDED/EXPANDED THROUGH LATE THIS AFTERNOON FOR MANY COUNTIES ALONG AND WEST OF THE BLUE RIDGE. THIS EXCLUDES PARTS OF THE NEW RIVER VALLEY AND NORTHWEST NORTH CAROLINA WHERE EARLIER RAINFALL WAS NOT AS HEAVY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR VAZ007- 009>015-018>020-022>024-034-035. NC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ001. WV...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...JH/NF NEAR TERM...DS/JH SHORT TERM...DS/JH LONG TERM...DS/WP AVIATION...JH/PM HYDROLOGY...JH CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
959 AM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 955 AM EDT SATURDAY... OUR FORECAST UPDATE THIS MORNING REFLECT AN ADJUSTMENT TO THE PLACEMENT AND TIMING OF PRECIPITATION ACROSS...OR EXPECTED TO MOVE INTO THE REGION. LITTLE IF ANY PRECIPITATION IS CURRENTLY FALLING ACROSS THE REGION...ALTHOUGH A GENEROUS AREA HAS JUST EXITED THE NORTH...AND ANOTHER REGION IS ABOUT TO ENTER FROM THE SOUTHWEST. THE UPDATE WILL REFLECT A LULL IN THE ACTIVITY...ESPECIALLY IN THE EAST...UNTIL ADDITIONAL PRECIPITATION CAN PROGRESS INTO THE AREA FROM THE SOUTHWEST...OR DEVELOP ACROSS THE AREA AS WE HEAD INTO THE AFTERNOON. NO OTHER NOTABLE CHANGES AT THIS TIME. AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /14Z SATURDAY THROUGH WEDNESDAY/... AS OF 705 AM EDT SATURDAY... SHOWERS HAVE REDEVELOPED ACROSS THE FAR WEST THIS MORNING AND EXPECT THESE TO PERSIST AROUND KBLF/KLWB THROUGH AT LEAST MID MORNING RESULTING IN MVFR CIGS AND PERHAPS MVFR VSBYS AT TIMES. SOME OF THESE SHOWERS LIKELY TO MOVE EAST TOWARD KBCB/KROA BEFORE SEEING ADDED REDEVELOPMENT OF STRONGER SHRA/TSRA TAKE SHAPE THIS AFTERNOON. OTRW EVEN WITHOUT SHOWERS...LOOKING AT LOW CONDITIONS OUTSIDE OF KDAN TO INIT WITH WIDESPREAD MVFR/IFR CIGS IN THE WAKE OF THE HEAVIER RAINFALL FROM OVERNIGHT. THINK SHOULD SEE SOME SLOW IMPROVEMENT TO CIGS THROUGH THE MORNING BUT ADDED SHRA MIGHT HOLD AT LEAST MVFR CONDITIONS IN PLACE LONGER SO SLOWED DOWN IMPROVEMENT UNTIL LATE MORNING/EARLY AFTERNOON. OTRW PRIMARY CONCERN THIS AFTERNOON IS WITH THE STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR LATER TODAY INTO THIS EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT LATE TONIGHT. ANTICIPATING ANOTHER BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT LATER THIS AFTERNOON...FOLLOWED BY PARTIAL CLEARING TONIGHT WITH GUSTY WESTERLY WINDS IN ALL EXCEPT THE UPSLOPE AREAS WHERE PERIODS OF MVFR CIGS LIKELY TO LINGER. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION THIS AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .HYDROLOGY... AS OF 655 AM EDT SATURDAY... A SWATH OF HEAVIER SHOWERS AND THUNDERSTORMS MOVED ACROSS MUCH OF THE REGION OVERNIGHT RESULTING IN SPOTS RECEIVING BETWEEN 1 AND 3 INCHES OF RAIN. THE MOST CONCENTRATED AREA OF HEAVY RAIN WAS ALONG/WEST OF THE BLUE RIDGE ESPECIALLY FROM ASHE COUNTY NORTH ACROSS THE MOUNTAIN EMPIRE REGION INTO SOUTHEAST WEST VIRGINIA AS WELL AS THE VIRGINIA HIGHLANDS. SHOWERS ARE EXPECTED TO REDEVELOP OVER THE MOUNTAINS THIS MORNING AND THEN SPREAD EAST WHILE STRENGTHENING AHEAD OF A STRONG COLD FRONT THAT WILL ARRIVE THIS EVENING. THE POTENTIAL EXISTS FOR LINES OR CLUSTERS OF STORMS TO DEVELOP AND OVER THE MOUNTAINS WHERE FLASH FLOOD GUIDANCE IS NOW LOWEST. RAINFALL OF 1 TO PERHAPS AS MUCH AS 3 INCHES COULD OCCUR WITH VERY HEAVY RAINFALL RATES EXCEEDING 2 INCHES AT HOUR AT TIMES. GIVEN THAT SOME AREAS ARE NOW MORE PRIMED FOR FLOODING THE EARLIER FLASH FLOOD WATCH WAS EXTENDED/EXPANDED THROUGH LATE THIS AFTERNOON FOR MANY COUNTIES ALONG AND WEST OF THE BLUE RIDGE. THIS EXCLUDES PARTS OF THE NEW RIVER VALLEY AND NORTHWEST NORTH CAROLINA WHERE EARLIER RAINFALL WAS NOT AS HEAVY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR VAZ007- 009>015-018>020-022>024-034-035. NC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ001. WV...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...JH/NF NEAR TERM...DS/JH SHORT TERM...DS/JH LONG TERM...DS/WP AVIATION...JH/PM HYDROLOGY...JH CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
713 AM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... AS OF 705 AM EDT SATURDAY... SHOWERS HAVE REDEVELOPED ACROSS THE FAR WEST THIS MORNING AND EXPECT THESE TO PERSIST AROUND KBLF/KLWB THROUGH AT LEAST MID MORNING RESULTING IN MVFR CIGS AND PERHAPS MVFR VSBYS AT TIMES. SOME OF THESE SHOWERS LIKELY TO MOVE EAST TOWARD KBCB/KROA BEFORE SEEING ADDED REDEVELOPMENT OF STRONGER SHRA/TSRA TAKE SHAPE THIS AFTERNOON. OTRW EVEN WITHOUT SHOWERS...LOOKING AT LOW CONDITIONS OUTSIDE OF KDAN TO INIT WITH WIDESPREAD MVFR/IFR CIGS IN THE WAKE OF THE HEAVIER RAINFALL FROM OVERNIGHT. THINK SHOULD SEE SOME SLOW IMPROVEMENT TO CIGS THROUGH THE MORNING BUT ADDED SHRA MIGHT HOLD AT LEAST MVFR CONDITIONS IN PLACE LONGER SO SLOWED DOWN IMPROVEMENT UNTIL LATE MORNING/EARLY AFTERNOON. OTRW PRIMARY CONCERN THIS AFTERNOON IS WITH THE STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR LATER TODAY INTO THIS EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT LATE TONIGHT. ANTICIPATING ANOTHER BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT LATER THIS AFTERNOON...FOLLOWED BY PARTIAL CLEARING TONIGHT WITH GUSTY WESTERLY WINDS IN ALL EXCEPT THE UPSLOPE AREAS WHERE PERIODS OF MVFR CIGS LIKELY TO LINGER. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION THIS AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .HYDROLOGY... AS OF 655 AM EDT SATURDAY... A SWATH OF HEAVIER SHOWERS AND THUNDERSTORMS MOVED ACROSS MUCH OF THE REGION OVERNIGHT RESULTING IN SPOTS RECEIVING BETWEEN 1 AND 3 INCHES OF RAIN. THE MOST CONCENTRATED AREA OF HEAVY RAIN WAS ALONG/WEST OF THE BLUE RIDGE ESPECIALLY FROM ASHE COUNTY NORTH ACROSS THE MOUNTAIN EMPIRE REGION INTO SOUTHEAST WEST VIRGINIA AS WELL AS THE VIRGINIA HIGHLANDS. SHOWERS ARE EXPECTED TO REDEVELOP OVER THE MOUNTAINS THIS MORNING AND THEN SPREAD EAST WHILE STRENGTHENING AHEAD OF A STRONG COLD FRONT THAT WILL ARRIVE THIS EVENING. THE POTENTIAL EXISTS FOR LINES OR CLUSTERS OF STORMS TO DEVELOP AND OVER THE MOUNTAINS WHERE FLASH FLOOD GUIDANCE IS NOW LOWEST. RAINFALL OF 1 TO PERHAPS AS MUCH AS 3 INCHES COULD OCCUR WITH VERY HEAVY RAINFALL RATES EXCEEDING 2 INCHES AT HOUR AT TIMES. GIVEN THAT SOME AREAS ARE NOW MORE PRIMED FOR FLOODING THE EARLIER FLASH FLOOD WATCH WAS EXTENDED/EXPANDED THROUGH LATE THIS AFTERNOON FOR MANY COUNTIES ALONG AND WEST OF THE BLUE RIDGE. THIS EXCLUDES PARTS OF THE NEW RIVER VALLEY AND NORTHWEST NORTH CAROLINA WHERE EARLIER RAINFALL WAS NOT AS HEAVY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR VAZ007- 009>015-018>020-022>024-034-035. NC...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR NCZ001. WV...FLASH FLOOD WATCH UNTIL 6 PM EDT THIS EVENING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...JH/NF NEAR TERM...JH SHORT TERM...DS/JH LONG TERM...DS/WP AVIATION...JH/PM HYDROLOGY...JH CLIMATE...DS EQUIPMENT...PM
AREA FORECAST DISCUSSION...UPDATED
NWS BLACKSBURG VA
350 AM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... AS OF 1240 AM EDT SATURDAY... CLUSTERS OF DEEP CONVECTION REMAIN OVER THE REGION TONIGHT ALONG AND NORTH OF A SLOW MOVING WARM FRONT THAT IS EXPECTED TO LIFT NE OF THE REGION BY SATURDAY MORNING. THIS WILL CONTINUE TO PRODUCE GUSTY SHRA/TSRA AT TIMES IN MOST LOCATIONS OVERNIGHT WITH PERIODS OF MVFR TO IFR CIGS AND VSBYS PENDING EXACTLY WHERE THE HEAVIER SHOWERS MOVE ACROSS. THUS WILL INIT WITH OVERALL MVFR CONDITIONS PER CURRENT OBS AND INCLUDE TEMPO GROUPS FOR LOWER VSBYS/CIGS WHERE APPEARS STRONGER CELLS MAY CROSS THROUGH MORNING. SOUTH WINDS ALSO GUSTY ACROSS THE WEST IN/NEAR CONVECTION AND ALONG THE FRONTAL PASSAGE. ELSEWHERE WILL SEE MORE OF AN EASTERLY COMPONENT THAT WILL SWING MORE TO THE SOUTH EARLY SATURDAY. PRIMARY CONCERN SATURDAY IS STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR DURING THE LATE AFTERNOON AND EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT SATURDAY NIGHT. ANTICIPATING BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT SATURDAY AFTERNOON...FOLLOWED BY PARTIAL CLEARING SATURDAY NIGHT WITH GUSTY WESTERLY WINDS. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION SATURDAY AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR VAZ007-009>015- 018>020-022>024-034-035. NC...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR NCZ001. WV...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR WVZ042>044-507- 508. && $$ SYNOPSIS...JH/NF NEAR TERM...JH SHORT TERM...DS/JH LONG TERM...DS/WP AVIATION...JH/PM CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
316 AM EDT SAT JUN 27 2015 .SYNOPSIS... A WARM FRONT WILL LIFT NORTH OF THE AREA BY THIS AFTERNOON AHEAD OF A DEEP LOW PRESSURE SYSTEM THAT WILL SLIDE UP THE OHIO RIVER VALLEY BY LATE IN THE DAY. THIS WILL BRING ADDITIONAL ROUNDS OF SHOWERS AND STORMS TO THE REGION INTO THIS EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA TONIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOL TEMPERATURES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM EDT SATURDAY... SWATH OF HEAVIER SHRA/TSRA JUST NORTH OF THE SURFACE WARM FRONT AND ALONG THE LOW LEVEL THETA-E GRADIENT CONTINUES TO WORK OFF TO THE NE AND SHOULD EXIT THE FAR NORTHERN COUNTIES AROUND SUNRISE. THIS WILL BRING A BRIEF LULL IN CONVECTION EARLY THIS MORNING AS THE WARM FRONT STARTS TO LIFT NORTH AHEAD OF THE UPSTREAM COLD FRONT THAT WONT MAKE IT INTO THE MOUNTAINS UNTIL EARLY THIS EVENING. THUS WILL GRADUALLY TRIM BACK POPS TO MOSTLY CHANCE TO START THE MORNING PER THE LATEST HRRR BEFORE HEATING COMMENCES AND STARTS TO RECHARGE THINGS AHEAD OF THE BOUNDARY THIS AFTERNOON. LATEST GUIDANCE REMAINS CONSISTENT IN BRINGING ADDED BANDS OF DEEPER CONVECTION INTO THE WEST BY AFTERNOON BEFORE THINGS LIKELY CONSOLIDATE HEADING OFF THE BLUE RIDGE TOWARD MID AFTERNOON IF NOT SOONER. HOWEVER BEST SUPPORT INCLUDING WINDS ALOFT WILL PASS TO THE NORTH WITH OVERALL BEST SHEAR ENDING UP ALONG THE WARM FRONT OVER NORTHERN VA. ALSO SIMILAR TO FRIDAY...WILL INIT WITH LITTLE INSTABILITY PER HEAVY RAIN FROM OVERNIGHT WHICH LOOKS TO LEAD TO SOMEWHAT WEAKER LAPSES/CAPES THIS AFTERNOON AS SEEN VIA THE LATEST NAM SHOWING ONLY 1K J/KG VALUES WEST AND PERHAPS 2K OUT EAST PENDING THE DEGREE OF HEATING BEFORE THINGS REDEVELOP. THIS SUPPORTS THE BEST SEVERE THREAT OUT EAST FOR MAINLY DAMAGING WINDS PER HEAVY PRECIP LOADING AS SEEING LITTLE DRY AIR ALOFT OFF FORECAST SOUNDINGS. OTRW SPEED OF BANDS/CLUSTERS SHOULD BE A BIT FASTER GIVEN THE 30-40 KT SW JET ALOFT. HOWEVER SINCE ALREADY HAVE A FLASH FLOOD WATCH IN PLACE WILL CLIP OFF A FEW COUNTIES ACROSS THE SOUTH WHERE RAINFALL HAS BEEN LESS AND ADD A COUPLE ALONG THE BLUE RIDGE UP NORTH. ALSO PLAN TO EXTEND THE WATCH OUT UNTIL 6 PM TO COVER HEAVY RAIN WITH THE FRONT AND MATCH UP WITH BORDERING OFFICES FOR NOW. THEREFORE KEPT LIKELY/CAT POPS THIS AFTERNOON WITH ONLY A SLOW EXODUS OF HEAVIER SHRA TO THE EAST AROUND 00Z WITH CHANCES LINGERING WEST UNTIL FROPA THIS EVENING. HIGH TEMPS A BIT COOLER GIVEN CLOUDS AROUND WITH MOSTLY 70S TO NEAR 80 WEST AND LOW/MID 80S EAST PROVIDED SOME SUN. COLD FRONT PUNCHES TO THE EAST OVERNIGHT ALLOWING A GOOD DRY SLOT TO WORK EAST AIDED BY 40 KTS AT 85H AND STRONG COOL ADVECTION UNDER THE PASSING UPPER TROUGH. THIS SHOULD BRING AN END TO MOST SHOWERS AFTER MIDNIGHT WITH ONLY SOME RESIDUAL UPSLOPE FLOW LIGHT SHOWERS POSSIBLE NW THROUGH DAYBREAK. WINDS LOOK GUSTY GIVEN THE ABRUPT 85H COOLING BUT BELOW ADVISORY LEVELS PER ONLY WEAK SUBSIDENCE. TEMPS WILL CRASH BACK INTO THE 50S OVER THE WEST WHERE WILL GET SOME CLEARING OUTSIDE OF THE UPSLOPE COUNTIES...WHILE EXPECT LOWS CLOSER TO 60-65 OUT EAST WHERE THE 85H FRONT WONT CROSS UNTIL LATE. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 315 AM EDT SATURDAY... GUSTY NW WINDS TO CONTINUE INTO SUNDAY UNDER A LINGERING GRADIENT BETWEEN THE UPPER LOW PASSING ACROSS NEW ENGLAND AND WEAK HIGH PRESSURE BUILDING IN FROM THE WEST. SHOULD AGAIN SEE SOME GUSTS TO 40-45 MPH MOUNTAINS MAINLY EARLY BEFORE SPEEDS DIMINISH SOME IN THE AFTERNOON. DOWNSLOPE DRYING AND SUBSIDENCE SHOULD LEAD TO CLEARING SKIES IN ALL BUT THE UPSLOPE AREAS WHERE WILL NEED TO KEEP A LOW END POP FOR ISOLATED SHOWERS NW INTO SUNDAY EVENING BEFORE THINGS DRY OUT. TEMPERATURES WILL CONTINUE TO TREND COOLER INTO SUNDAY. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS AND PERHAPS A FEW 40S DEEPER VALLEYS...WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS THE FAR SW DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /07Z SATURDAY THROUGH WEDNESDAY/... AS OF 1240 AM EDT SATURDAY... CLUSTERS OF DEEP CONVECTION REMAIN OVER THE REGION TONIGHT ALONG AND NORTH OF A SLOW MOVING WARM FRONT THAT IS EXPECTED TO LIFT NE OF THE REGION BY SATURDAY MORNING. THIS WILL CONTINUE TO PRODUCE GUSTY SHRA/TSRA AT TIMES IN MOST LOCATIONS OVERNIGHT WITH PERIODS OF MVFR TO IFR CIGS AND VSBYS PENDING EXACTLY WHERE THE HEAVIER SHOWERS MOVE ACROSS. THUS WILL INIT WITH OVERALL MVFR CONDITIONS PER CURRENT OBS AND INCLUDE TEMPO GROUPS FOR LOWER VSBYS/CIGS WHERE APPEARS STRONGER CELLS MAY CROSS THROUGH MORNING. SOUTH WINDS ALSO GUSTY ACROSS THE WEST IN/NEAR CONVECTION AND ALONG THE FRONTAL PASSAGE. ELSEWHERE WILL SEE MORE OF AN EASTERLY COMPONENT THAT WILL SWING MORE TO THE SOUTH EARLY SATURDAY. PRIMARY CONCERN SATURDAY IS STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR DURING THE LATE AFTERNOON AND EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT SATURDAY NIGHT. ANTICIPATING BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT SATURDAY AFTERNOON...FOLLOWED BY PARTIAL CLEARING SATURDAY NIGHT WITH GUSTY WESTERLY WINDS. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION SATURDAY AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR VAZ007-009>014- 018>020-022>024-034-035. NC...NONE. WV...FLASH FLOOD WATCH THROUGH THIS AFTERNOON FOR WVZ042>044-507- 508. && $$ SYNOPSIS...JH/NF NEAR TERM...JH SHORT TERM...DS/JH LONG TERM...DS/WP AVIATION...JH/PM CLIMATE...JH EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1256 AM EDT SAT JUN 27 2015 .SYNOPSIS... A DEEP LOW PRESSURE SYSTEM WILL MOVE UP THE OHIO RIVER VALLEY TONIGHT AND SATURDAY...TRIGGERING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FROM TONIGHT THROUGH SATURDAY EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY NIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOLER TEMPERATURES. && .NEAR TERM /THROUGH TODAY/... AS OF 1245 AM EDT SATURDAY... QUICK UPDATE TO DROP SEVERE WATCH 363 WHICH INCLUDED SMYTH AND TAZEWELL COUNTIES. APPEARS DEEPER CONVECTION WILL REMAIN NE OF THE REGION OVERNIGHT WITH MAINLY A HEAVY RAIN THREAT PERSISTING INTO THE OVERNIGHT. FLASH FLOOD WATCH HAS BEEN ISSUED FOR PARTS OF THE FORECAST AREA WITH PRIMARY FOCUS ALONG AND WEST OF THE BLUE RIDGE FOR EXCESSIVE RAINFALL. A FRONTAL BOUNDARY REMAINS STALLED ACROSS THE FORECAST AREA. THIS FEATURE WILL PROVIDE AS A FOCUSING MECHANISM FOR SHOWERS/STORMS THROUGH THE OVERNIGHT. ENHANCEMENT OF SHOWERS ACROSS THE AREA IS EXPECTED AS EASTERLY UPSLOPE FLOW INCREASES PROVIDING ADDITIONAL LIFT AND CONCENTRATION OF DEEPER MOISTURE ALONG THE BLUE RIDGE. THE COMBINATION OF INCREASING COVERAGE OF DEEP CONVECTION, INCREASING UPSLOPE FLOW, AND LINGERING INSTABILITY COULD CAUSE FLASH FLOODING IN STEEP TERRAIN. THEREFORE A FLASH FLOOD WATCH HAS BEEN ISSUED FOR AREAS ALONG AND WEST OF THE BLUE RIDGE. SPECIAL DISCUSSION FROM THE WEATHER PREDICTION CENTER... SURFACE ANALYSIS REVEALS A WEAK WAVE ACROSS NORTHWEST SC WHICH HAS BEGUN INCREASING UPSLOPE FLOW WITHIN THE TERRAIN TO ITS NORTH PER RECENT FCX VAD WIND PROFILES. PRECIPITABLE WATER VALUES ARE 1.3-1.5" PER GPS INFORMATION ACROSS SOUTHWEST VA, WITH HIGHER VALUES ACROSS WV. IN ADDITION, CONVECTION FROM NORTHEAST TN, EASTERN KY, AND NORTHWEST NC IS MOVING INTO THE AREA AT ~20 KTS, THE MAGNITUDE OF THE FORWARD PROPAGATING CONVECTIVE VECTORS. UPSTREAM MUCAPES (USING 850 HPA WINDS) ARE 1000-2000 J/KG, WHICH SHOULD BE SUFFICIENT CONSIDERING MOISTENING ATMOSPHERIC PROFILES. THE EXPECTATION IS FOR ACTIVITY FROM THE SOUTHWEST OF THE REGION TO MOVE INTO THE REGION AND FOR NEW ACTIVITY TO FORM ALONG PORTIONS OF THE BLUE RIDGE MOUNTAINS AS UPSLOPE FLOW INCREASES. THIS ACTIVITY SHOULD SHIFT NORTHEAST UP THE TERRAIN AS AN INVERTED TROUGH AS THE SURFACE/850 HPA MOVES NORTHEAST WITH TIME. SOME REDEVELOPMENT ALONG THE BLUE RIDGE IS POSSIBLE AS INITIAL CELLS PROPAGATE EASTWARD AT 20 KTS AWAY FROM THE TERRAIN. RAP FORECASTS INDICATE MINIMAL CHANGE IN THE MUCAPES ACROSS NC AND SOUTHERN VA OVERNIGHT. HOURLY RAIN RATES UP TO 2" ARE POSSIBLE CONSIDERING THE AVAILABLE MOISTURE. THERE IS A MODEST SIGNAL FOR LOCAL AMOUNTS OF 2-4" WITHIN THE MESOSCALE GUIDANCE NEAR THIS AREA. THE PERFORMANCE OF THE MESOSCALE QPF GUIDANCE APPEARS SUB-PAR PER RECENT RADAR IMAGERY. THE 12Z ARW AND RECENT RAP/HRRR RUNS SEEM TO BE HANDLING THE CONVECTIVE POSSIBILITIES THE BEST. END OF SPECIAL DISCUSSION. FOR SATURDAY...FRONT OVER THE AREA IS EXPECTED TO LIFT NORTH AS A WARM FRONT SATURDAY...ALLOWING WINDS TO SHIFT SOUTHWESTERLY AREAWIDE. THIS SHOULD PROVIDE A BREAK IN THE RAINFALL THREAT FOR A FEW HOURS BEFORE THE SUPPORTING UPPER LEVEL TROUGH ASSOCIATED WITH THE LOW PUSHES A BKN-SOLID LINE OF SHOWERS AND STORMS ACROSS OUR AREA FROM THE WEST. GUSTY WINDS AND LOCALLY HEAVY RAIN WILL BE POSSIBLE WITH THE STORMS. CONCERNING THE POTENTIAL FOR WIDESPREAD HEAVY RAIN... FORECAST MODELS CONTINUE TO TREND FURTHER WEST AND NORTH WITH THE BRUNT OF HEAVY RAIN ASSOCIATED WITH THE LOW...KEEPING IT MORE CONFINED ALONG AND NORTH OF THE OHIO RIVER. WHILE LOCALLY HEAVY RAIN MAY RESULT IN A FEW FLOODING ISSUES ACROSS OUR AREA...BELIEVE WE WILL NOT SEE ENOUGH WIDESPREAD HEAVY RAIN TO SUPPORT A FLASH FLOOD WATCH AT THIS TIME. THAT SAID...WITH INCREASING EASTERLY UPSLOPE FLOW LATE TONIGHT...WILL HAVE TO MONITOR FOR LOCALIZED FLASH FLOODING DUE TO THE POTENTIAL FOR STORM CELLS TO BECOME ANCHORED NEAR CREST OF BLUE RIDGE WHERE UPSLOPE FLOW WILL BE THE GREATEST. CONFIDENCE IS JUST NOT GREAT ENOUGH ATTM TO PINPOINT EXACT LOCATION WHERE THE ANCHORING WILL OCCUR. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... AS OF 250 PM EDT FRIDAY... THE BIG STORY DURING THIS PORTION OF THE FORECAST WILL BE THE WINTERISH GRADIENT WINDS WE WILL EXPERIENCE ON THE BACKSIDE OF THE DEPARTING COLD FRONT...FOLLOWED BY MUCH COOLER CONDITIONS. THE PARENT UPPER LOW WILL MAKE ITS WAY SLOWLY EASTWARD SATURDAY NIGHT FROM THE THUMB OF MICHIGAN TO NEAR ERIE PA. THE 850 MB FLOW AROUND THE LOW IS PROGGED TO PEAK IN THE 40 TO 50 KT RANGE AROUND 12Z SUNDAY. MOST AREAS IN THE MOUNTAINS ACROSS THE REGION LATE SATURDAY NIGHT TROUGH AT LEAST MID-DAY SUNDAY WILL SEE WIND GUSTS IN THE 20 TO 30 MPH RANGE...WITH THE HIGHEST RIDGE TOPS EXPERIENCING GUSTS OF 40 TO 45 MPH. WIND SPEEDS AND GUSTS WILL DECREASE THROUGH THE AFTERNOON WITH 850 MB WINDS PROGGED TO DECREASE TO AROUND 15 TO 20 KTS BY SUNSET SUNDAY. PRECIPITATION SATURDAY NIGHT AND SUNDAY WILL BE CONFINED TO TWO MAIN AREAS. THERE WILL BE LINGERING SHOWERS AND SOME STORMS ACROSS THE SOUTHEAST PART OF THE AREA COINCIDENT TO AND BEHIND THE DEPARTING COLD FRONT. THE LAST FEW SHOWERS IN THIS PART OF THE FORECAST AREA MAY LINGER UNTIL 200 AM TO 500 AM SUNDAY MORNING. THE OTHER AREA OF PRECIPITATION WILL BE ISOLATED TO SCATTERED UPSLOPE SHOWERS ACROSS THE PREFERRED AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. COVERAGE WILL DECREASE DURING THE AFTERNOON SUNDAY AS THE WIND SPEEDS SLACKEN. TEMPERATURES WILL TREND COOLER SATURDAY NIGHT INTO SUNDAY. LOWS SATURDAY NIGHT WILL RANGE FROM THE MID TO UPPER 50S ACROSS THE MOUNTAINS WITH UPPER 50S TO LOWER 60S ACROSS THE PIEDMONT. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS SOUTHEAST WEST VIRGINIA DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... AS OF 1240 AM EDT SATURDAY... CLUSTERS OF DEEP CONVECTION REMAIN OVER THE REGION TONIGHT ALONG AND NORTH OF A SLOW MOVING WARM FRONT THAT IS EXPECTED TO LIFT NE OF THE REGION BY SATURDAY MORNING. THIS WILL CONTINUE TO PRODUCE GUSTY SHRA/TSRA AT TIMES IN MOST LOCATIONS OVERNIGHT WITH PERIODS OF MVFR TO IFR CIGS AND VSBYS PENDING EXACTLY WHERE THE HEAVIER SHOWERS MOVE ACROSS. THUS WILL INIT WITH OVERALL MVFR CONDITIONS PER CURRENT OBS AND INCLUDE TEMPO GROUPS FOR LOWER VSBYS/CIGS WHERE APPEARS STRONGER CELLS MAY CROSS THROUGH MORNING. SOUTH WINDS ALSO GUSTY ACROSS THE WEST IN/NEAR CONVECTION AND ALONG THE FRONTAL PASSAGE. ELSEWHERE WILL SEE MORE OF AN EASTERLY COMPONENT THAT WILL SWING MORE TO THE SOUTH EARLY SATURDAY. PRIMARY CONCERN SATURDAY IS STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR DURING THE LATE AFTERNOON AND EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT SATURDAY NIGHT. ANTICIPATING BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT SATURDAY AFTERNOON...FOLLOWED BY PARTIAL CLEARING SATURDAY NIGHT WITH GUSTY WESTERLY WINDS. GIVEN UNCERTAINTY WITH TIMING OF WHEN BANDS MIGHT CROSS WILL LEAVE IN AN OVERALL VICINITY MENTION SATURDAY AFTERNOON AFTER MORNING SHRA EXIT FOR NOW. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. ANOTHER DISTURBANCE SLIDING IN FROM THE NW MAY BRING THE NEXT ROUND OF SUB-VFR CONDITIONS ESPCLY ACROSS THE MOUNTAINS ON WEDNESDAY. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR VAZ007- 009>020-022>024. NC...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR NCZ001-002. WV...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...NF NEAR TERM...JH/NF/PM SHORT TERM...DS LONG TERM...DS/WP AVIATION...JH/PM CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1204 AM EDT SAT JUN 27 2015 .SYNOPSIS... A DEEP LOW PRESSURE SYSTEM WILL MOVE UP THE OHIO RIVER VALLEY TONIGHT AND SATURDAY...TRIGGERING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FROM TONIGHT THROUGH SATURDAY EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY NIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOLER TEMPERATURES. && .NEAR TERM /THROUGH TODAY/... AS OF 1200 AM EDT SATURDAY... FLASH FLOOD WATCH HAS BEEN ISSUED FOR PARTS OF THE FORECAST AREA WITH PRIMARY FOCUS ALONG AND WEST OF THE BLUE RIDGE FOR EXCESSIVE RAINFALL. A FRONTAL BOUNDARY REMAINS STALLED ACROSS THE FORECAST AREA. THIS FEATURE WILL PROVIDE AS A FOCUSSING MECHANISM FOR SHOWERS/STORMS THROUGH THE OVERNIGHT. ENHANCEMENT OF SHOWERS ACROSS THE AREA IS EXPECTED AS EASTERLY UPSLOPE FLOW INCREASES PROVIDING ADDITIONAL LIFT AND CONCENTRATION OF DEEPER MOISTURE ALONG THE BLUE RIDGE. THE COMBINATION OF INCREASING COVERAGE OF DEEP CONVECTION, INCREASING UPSLOPE FLOW, AND LINGERING INSTABILITY COULD CAUSE FLASH FLOODING IN STEEP TERRAIN. THEREFORE A FLASH FLOOD WATCH HAS BEEN ISSUED FOR AREAS ALONG AND WEST OF THE BLUE RIDGE. SPECIAL DISCUSSION FROM THE WEATHER PREDICTION CENTER... SURFACE ANALYSIS REVEALS A WEAK WAVE ACROSS NORTHWEST SC WHICH HAS BEGUN INCREASING UPSLOPE FLOW WITHIN THE TERRAIN TO ITS NORTH PER RECENT FCX VAD WIND PROFILES. PRECIPITABLE WATER VALUES ARE 1.3-1.5" PER GPS INFORMATION ACROSS SOUTHWEST VA, WITH HIGHER VALUES ACROSS WV. IN ADDITION, CONVECTION FROM NORTHEAST TN, EASTERN KY, AND NORTHWEST NC IS MOVING INTO THE AREA AT ~20 KTS, THE MAGNITUDE OF THE FORWARD PROPAGATING CONVECTIVE VECTORS. UPSTREAM MUCAPES (USING 850 HPA WINDS) ARE 1000-2000 J/KG, WHICH SHOULD BE SUFFICIENT CONSIDERING MOISTENING ATMOSPHERIC PROFILES. THE EXPECTATION IS FOR ACTIVITY FROM THE SOUTHWEST OF THE REGION TO MOVE INTO THE REGION AND FOR NEW ACTIVITY TO FORM ALONG PORTIONS OF THE BLUE RIDGE MOUNTAINS AS UPSLOPE FLOW INCREASES. THIS ACTIVITY SHOULD SHIFT NORTHEAST UP THE TERRAIN AS AN INVERTED TROUGH AS THE SURFACE/850 HPA MOVES NORTHEAST WITH TIME. SOME REDEVELOPMENT ALONG THE BLUE RIDGE IS POSSIBLE AS INITIAL CELLS PROPAGATE EASTWARD AT 20 KTS AWAY FROM THE TERRAIN. RAP FORECASTS INDICATE MINIMAL CHANGE IN THE MUCAPES ACROSS NC AND SOUTHERN VA OVERNIGHT. HOURLY RAIN RATES UP TO 2" ARE POSSIBLE CONSIDERING THE AVAILABLE MOISTURE. THERE IS A MODEST SIGNAL FOR LOCAL AMOUNTS OF 2-4" WITHIN THE MESOSCALE GUIDANCE NEAR THIS AREA. THE PERFORMANCE OF THE MESOSCALE QPF GUIDANCE APPEARS SUB-PAR PER RECENT RADAR IMAGERY. THE 12Z ARW AND RECENT RAP/HRRR RUNS SEEM TO BE HANDLING THE CONVECTIVE POSSIBILITIES THE BEST. END OF SPECIAL DISCUSSION. FOR SATURDAY...FRONT OVER THE AREA IS EXPECTED TO LIFT NORTH AS A WARM FRONT SATURDAY...ALLOWING WINDS TO SHIFT SOUTHWESTERLY AREAWIDE. THIS SHOULD PROVIDE A BREAK IN THE RAINFALL THREAT FOR A FEW HOURS BEFORE THE SUPPORTING UPPER LEVEL TROUGH ASSOCIATED WITH THE LOW PUSHES A BKN-SOLID LINE OF SHOWERS AND STORMS ACROSS OUR AREA FROM THE WEST. GUSTY WINDS AND LOCALLY HEAVY RAIN WILL BE POSSIBLE WITH THE STORMS. CONCERNING THE POTENTIAL FOR WIDESPREAD HEAVY RAIN... FORECAST MODELS CONTINUE TO TREND FURTHER WEST AND NORTH WITH THE BRUNT OF HEAVY RAIN ASSOCIATED WITH THE LOW...KEEPING IT MORE CONFINED ALONG AND NORTH OF THE OHIO RIVER. WHILE LOCALLY HEAVY RAIN MAY RESULT IN A FEW FLOODING ISSUES ACROSS OUR AREA...BELIEVE WE WILL NOT SEE ENOUGH WIDESPREAD HEAVY RAIN TO SUPPORT A FLASH FLOOD WATCH AT THIS TIME. THAT SAID...WITH INCREASING EASTERLY UPSLOPE FLOW LATE TONIGHT...WILL HAVE TO MONITOR FOR LOCALIZEDFLASH FLOODING DUE TO THE POTENTIAL FOR STORM CELLS TO BECOME ANCHORED NEAR CREST OF BLUE RIDGE WHERE UPSLOPE FLOW WILL BE THE GREATEST. CONFIDENCE IS JUST NOT GREAT ENOUGH ATTM TO PINPOINT EXACT LOCATION WHERE THE ANCHORING WILL OCCUR. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... AS OF 250 PM EDT FRIDAY... THE BIG STORY DURING THIS PORTION OF THE FORECAST WILL BE THE WINTERISH GRADIENT WINDS WE WILL EXPERIENCE ON THE BACKSIDE OF THE DEPARTING COLD FRONT...FOLLOWED BY MUCH COOLER CONDITIONS. THE PARENT UPPER LOW WILL MAKE ITS WAY SLOWLY EASTWARD SATURDAY NIGHT FROM THE THUMB OF MICHIGAN TO NEAR ERIE PA. THE 850 MB FLOW AROUND THE LOW IS PROGGED TO PEAK IN THE 40 TO 50 KT RANGE AROUND 12Z SUNDAY. MOST AREAS IN THE MOUNTAINS ACROSS THE REGION LATE SATURDAY NIGHT TROUGH AT LEAST MID-DAY SUNDAY WILL SEE WIND GUSTS IN THE 20 TO 30 MPH RANGE...WITH THE HIGHEST RIDGE TOPS EXPERIENCING GUSTS OF 40 TO 45 MPH. WIND SPEEDS AND GUSTS WILL DECREASE THROUGH THE AFTERNOON WITH 850 MB WINDS PROGGED TO DECREASE TO AROUND 15 TO 20 KTS BY SUNSET SUNDAY. PRECIPITATION SATURDAY NIGHT AND SUNDAY WILL BE CONFINED TO TWO MAIN AREAS. THERE WILL BE LINGERING SHOWERS AND SOME STORMS ACROSS THE SOUTHEAST PART OF THE AREA COINCIDENT TO AND BEHIND THE DEPARTING COLD FRONT. THE LAST FEW SHOWERS IN THIS PART OF THE FORECAST AREA MAY LINGER UNTIL 200 AM TO 500 AM SUNDAY MORNING. THE OTHER AREA OF PRECIPITATION WILL BE ISOLATED TO SCATTERED UPSLOPE SHOWERS ACROSS THE PREFERRED AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. COVERAGE WILL DECREASE DURING THE AFTERNOON SUNDAY AS THE WIND SPEEDS SLACKEN. TEMPERATURES WILL TREND COOLER SATURDAY NIGHT INTO SUNDAY. LOWS SATURDAY NIGHT WILL RANGE FROM THE MID TO UPPER 50S ACROSS THE MOUNTAINS WITH UPPER 50S TO LOWER 60S ACROSS THE PIEDMONT. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS SOUTHEAST WEST VIRGINIA DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... AS OF 800 PM EDT FRIDAY... VFR CONDITIONS THIS EVENING ARE EXPECTED TO DETERIORATE AFTER MIDNIGHT AS DEEP CONVECTION FROM THUNDERSTORM COMPLEX WEST OF THE APPALACHIANS CROSSES THE MOUNTAINS DURING THE OVERNIGHT. NOT CONFIDENT ENOUGH ON EXACT TIMING OF TSRA...THUS LEAVING OUT OF TAFS ATTM. MORE CONFIDENT ON INCREASING CLOUDS AND INCREASING COVERAGE OF SHOWERS WITH POTENTIAL FOR MVFR CIGS PER INCREASING UPSLOPE EASTERLY FLOW DURING THE OVERNIGHT. MODELS HINT THAT CIGS COULD DROP TO IFR AFTER 06Z/2AM...BUT WOULD LIKE TO SEE INCREASING COVERAGE OF RAIN COOLED AIR BEFORE FORECASTING THE LOW CIGS. PRIMARY CONCERN SATURDAY IS STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR DURING THE LATE AFTERNOON AND EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT SATURDAY NIGHT. ANTICIPATING BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT SATURDAY AFTERNOON...FOLLOWED BY PARTIAL CLEARING SATURDAY NIGHT WITH GUSTY WESTERLY WINDS. THESE WINDS ARE EXPECTED TO PERSIST INTO THE DAY SUNDAY BEFORE DIMINISHING. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR VAZ007- 009>020-022>024. NC...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR NCZ001-002. WV...FLASH FLOOD WATCH UNTIL 10 AM EDT THIS MORNING FOR WVZ042>044- 507-508. && $$ SYNOPSIS...NF NEAR TERM...NF/PM SHORT TERM...DS LONG TERM...DS/WP AVIATION...PM CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1203 AM EDT SAT JUN 27 2015 .SYNOPSIS... A DEEP LOW PRESSURE SYSTEM WILL MOVE UP THE OHIO RIVER VALLEY TONIGHT AND SATURDAY...TRIGGERING INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FROM TONIGHT THROUGH SATURDAY EVENING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY NIGHT...RESULTING IN GUSTY NORTHWEST WINDS AND UNSEASONABLY COOLER TEMPERATURES. && .NEAR TERM /THROUGH SATURDAY/... AS OF 1200 AM EDT SATURDAY... A FRONTAL BOUNDARY REMAINS STALLED ACROSS THE FORECAST AREA. THIS FEATURE WILL PROVIDE AS A FOCUSSING MECHANISM FOR SHOWERS/STORMS THROUGH THE OVERNIGHT. ENHANCEMENT OF SHOWERS ACROSS THE AREA IS EXPECTED AS EASTERLY UPSLOPE FLOW INCREASES PROVIDING ADDITIONAL LIFT AND CONCENTRATION OF DEEPER MOISTURE ALONG THE BLUE RIDGE. THE COMBINATION OF INCREASING COVERAGE OF DEEP CONVECTION, INCREASING UPSLOPE FLOW, AND LINGERING INSTABILITY COULD CAUSE FLASH FLOODING IN STEEP TERRAIN. THEREFORE A FLASH FLOOD WATCH HAS BEEN ISSUED FOR AREAS ALONG AND WEST OF THE BLUE RIDGE. SPECIAL DISCUSSION FROM THE WEATHER PREDICTION CENTER... SURFACE ANALYSIS REVEALS A WEAK WAVE ACROSS NORTHWEST SC WHICH HAS BEGUN INCREASING UPSLOPE FLOW WITHIN THE TERRAIN TO ITS NORTH PER RECENT FCX VAD WIND PROFILES. PRECIPITABLE WATER VALUES ARE 1.3-1.5" PER GPS INFORMATION ACROSS SOUTHWEST VA, WITH HIGHER VALUES ACROSS WV. IN ADDITION, CONVECTION FROM NORTHEAST TN, EASTERN KY, AND NORTHWEST NC IS MOVING INTO THE AREA AT ~20 KTS, THE MAGNITUDE OF THE FORWARD PROPAGATING CONVECTIVE VECTORS. UPSTREAM MUCAPES (USING 850 HPA WINDS) ARE 1000-2000 J/KG, WHICH SHOULD BE SUFFICIENT CONSIDERING MOISTENING ATMOSPHERIC PROFILES. THE EXPECTATION IS FOR ACTIVITY FROM THE SOUTHWEST OF THE REGION TO MOVE INTO THE REGION AND FOR NEW ACTIVITY TO FORM ALONG PORTIONS OF THE BLUE RIDGE MOUNTAINS AS UPSLOPE FLOW INCREASES. THIS ACTIVITY SHOULD SHIFT NORTHEAST UP THE TERRAIN AS AN INVERTED TROUGH AS THE SURFACE/850 HPA MOVES NORTHEAST WITH TIME. SOME REDEVELOPMENT ALONG THE BLUE RIDGE IS POSSIBLE AS INITIAL CELLS PROPAGATE EASTWARD AT 20 KTS AWAY FROM THE TERRAIN. RAP FORECASTS INDICATE MINIMAL CHANGE IN THE MUCAPES ACROSS NC AND SOUTHERN VA OVERNIGHT. HOURLY RAIN RATES UP TO 2" ARE POSSIBLE CONSIDERING THE AVAILABLE MOISTURE. THERE IS A MODEST SIGNAL FOR LOCAL AMOUNTS OF 2-4" WITHIN THE MESOSCALE GUIDANCE NEAR THIS AREA. THE PERFORMANCE OF THE MESOSCALE QPF GUIDANCE APPEARS SUB-PAR PER RECENT RADAR IMAGERY. THE 12Z ARW AND RECENT RAP/HRRR RUNS SEEM TO BE HANDLING THE CONVECTIVE POSSIBILITIES THE BEST. END OF SPECIAL DISCUSSION. FOR SATURDAY...FRONT OVER THE AREA IS EXPECTED TO LIFT NORTH AS A WARM FRONT SATURDAY...ALLOWING WINDS TO SHIFT SOUTHWESTERLY AREAWIDE. THIS SHOULD PROVIDE A BREAK IN THE RAINFALL THREAT FOR A FEW HOURS BEFORE THE SUPPORTING UPPER LEVEL TROUGH ASSOCIATED WITH THE LOW PUSHES A BKN-SOLID LINE OF SHOWERS AND STORMS ACROSS OUR AREA FROM THE WEST. GUSTY WINDS AND LOCALLY HEAVY RAIN WILL BE POSSIBLE WITH THE STORMS. CONCERNING THE POTENTIAL FOR WIDESPREAD HEAVY RAIN... FORECAST MODELS CONTINUE TO TREND FURTHER WEST AND NORTH WITH THE BRUNT OF HEAVY RAIN ASSOCIATED WITH THE LOW...KEEPING IT MORE CONFINED ALONG AND NORTH OF THE OHIO RIVER. WHILE LOCALLY HEAVY RAIN MAY RESULT IN A FEW FLOODING ISSUES ACROSS OUR AREA...BELIEVE WE WILL NOT SEE ENOUGH WIDESPREAD HEAVY RAIN TO SUPPORT A FLASH FLOOD WATCH AT THIS TIME. THAT SAID...WITH INCREASING EASTERLY UPSLOPE FLOW LATE TONIGHT...WILL HAVE TO MONITOR FOR LOCALIZEDFLASH FLOODING DUE TO THE POTENTIAL FOR STORM CELLS TO BECOME ANCHORED NEAR CREST OF BLUE RIDGE WHERE UPSLOPE FLOW WILL BE THE GREATEST. CONFIDENCE IS JUST NOT GREAT ENOUGH ATTM TO PINPOINT EXACT LOCATION WHERE THE ANCHORING WILL OCCUR. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... AS OF 250 PM EDT FRIDAY... THE BIG STORY DURING THIS PORTION OF THE FORECAST WILL BE THE WINTERISH GRADIENT WINDS WE WILL EXPERIENCE ON THE BACKSIDE OF THE DEPARTING COLD FRONT...FOLLOWED BY MUCH COOLER CONDITIONS. THE PARENT UPPER LOW WILL MAKE ITS WAY SLOWLY EASTWARD SATURDAY NIGHT FROM THE THUMB OF MICHIGAN TO NEAR ERIE PA. THE 850 MB FLOW AROUND THE LOW IS PROGGED TO PEAK IN THE 40 TO 50 KT RANGE AROUND 12Z SUNDAY. MOST AREAS IN THE MOUNTAINS ACROSS THE REGION LATE SATURDAY NIGHT TROUGH AT LEAST MID-DAY SUNDAY WILL SEE WIND GUSTS IN THE 20 TO 30 MPH RANGE...WITH THE HIGHEST RIDGE TOPS EXPERIENCING GUSTS OF 40 TO 45 MPH. WIND SPEEDS AND GUSTS WILL DECREASE THROUGH THE AFTERNOON WITH 850 MB WINDS PROGGED TO DECREASE TO AROUND 15 TO 20 KTS BY SUNSET SUNDAY. PRECIPITATION SATURDAY NIGHT AND SUNDAY WILL BE CONFINED TO TWO MAIN AREAS. THERE WILL BE LINGERING SHOWERS AND SOME STORMS ACROSS THE SOUTHEAST PART OF THE AREA COINCIDENT TO AND BEHIND THE DEPARTING COLD FRONT. THE LAST FEW SHOWERS IN THIS PART OF THE FORECAST AREA MAY LINGER UNTIL 200 AM TO 500 AM SUNDAY MORNING. THE OTHER AREA OF PRECIPITATION WILL BE ISOLATED TO SCATTERED UPSLOPE SHOWERS ACROSS THE PREFERRED AREAS OF SOUTHEAST WEST VIRGINIA...SOUTH INTO THE NORTHERN MOUNTAINS OF NORTH CAROLINA. COVERAGE WILL DECREASE DURING THE AFTERNOON SUNDAY AS THE WIND SPEEDS SLACKEN. TEMPERATURES WILL TREND COOLER SATURDAY NIGHT INTO SUNDAY. LOWS SATURDAY NIGHT WILL RANGE FROM THE MID TO UPPER 50S ACROSS THE MOUNTAINS WITH UPPER 50S TO LOWER 60S ACROSS THE PIEDMONT. HIGHS ON SUNDAY WILL RANGE FROM AROUND 70 TO THE LOWER 70S ACROSS THE MOUNTAINS TO THE UPPER 70S TO AROUND 80 ACROSS THE PIEDMONT. DRY AND COOL HIGH PRESSURE WILL SETTLE OVER THE REGION ON SUNDAY NIGHT. EXPECT NO PRECIPITATION WITH BELOW NORMAL TEMPERATURES. LOWS WILL RANGE FROM THE LOW TO MID 50S ACROSS THE MOUNTAINS WITH UPPER 50S ACROSS THE PIEDMONT. WHILE NO RECORD LOW TEMPERATURES ARE FORECAST...A FEW LOCATIONS WILL FALL TO READINGS WITHIN FIVE DEGREES OF RECORD LOWS. SEE THE CLIMATE SECTION OF THIS DISCUSSION FOR DETAILS. ON MONDAY...THE CENTER OF THE SURFACE HIGH PRESSURE WILL PROGRESS EASTWARD IN ADVANCE OF OUR NEXT GREAT LAKES SHORTWAVE TROUGH. EXPECT A RETURN OF A SOUTHERLY COMPONENT OF THE LOW LEVEL WINDS AND INCREASING DEW POINTS AND TEMPERATURES. WHILE NO PRECIPITATION IS FORECAST FOR THE MORNING...SOME ISOLATED SHOWERS MAY DEVELOP ACROSS SOUTHEAST WEST VIRGINIA DURING THE AFTERNOON. HIGH TEMPERATURES WILL AVERAGE 5 TO 7 DEGREES MILDER THAN THOSE OF SUNDAY. ANTICIPATE UPPER 70S TO AROUND 80 IN THE MOUNTAINS AND LOW TO MID 80S ACROSS THE PIEDMONT. ON MONDAY NIGHT...THE TROUGH AXIS OF THE GREAT LAKES SYSTEM WILL START PROGRESSING THROUGH THE OHIO VALLEY. LOOK FOR SHOWERS AND STORMS TO EXPAND IN COVERAGE ACROSS THE WESTERN PARTS OF THE AREA. STILL LITTLE OR NO COVERAGE IS ANTICIPATED FOR AREAS EAST OF THE CREST OF THE BLUE RIDGE. LOW TEMPERATURES WILL RANGE FROM THE UPPER 50S TO AROUND 60 ACROSS THE MOUNTAINS TO THE LOWER 60S ACROSS THE PIEDMONT. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 320 PM EDT FRIDAY... THIS PORTION OF THE FORECAST PERIOD IS EXPECTED TO BE ONE WITH SCATTERED SHOWERS AND STORMS ACROSS THE AREA EACH DAY AND NIGHT. THE AXIS OF A SHORTWAVE TROUGH WILL MOVE THROUGH THE REGION BY MIDDAY TUESDAY. THE COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO STALL OVER...OR JUST SOUTH OF THE AREA...AND TAKE ON A NW-SE ORIENTATION. THROUGH FRIDAY...LITTLE MOVEMENT OF THIS FRONT IS EXPECTED. THE COMBINATION OF DAYTIME HEATING...AND THE POTENTIAL FOR ADDITIONAL WAVES OF ENERGY MOVING SOUTHEAST ALONG THIS FEATURE WILL BE THE SOURCE OF THE FORECAST SCATTERED SHOWERS AND SOME STORMS. HIGH TEMPERATURES DURING THIS PORTION OF THE FORECAST WILL RANGE FROM THE UPPER 70S TO AROUND 80 ACROSS THE MOUNTAINS AND MID TO UPPER 80S ACROSS THE PIEDMONT. LOW TEMPERATURES WILL MAINLY BE IN THE LOWER 60S ACROSS THE MOUNTAINS AND UPPER 60S ACROSS THE PIEDMONT. && .AVIATION /04Z SATURDAY THROUGH WEDNESDAY/... AS OF 800 PM EDT FRIDAY... VFR CONDITIONS THIS EVENING ARE EXPECTED TO DETERIORATE AFTER MIDNIGHT AS DEEP CONVECTION FROM THUNDERSTORM COMPLEX WEST OF THE APPALACHIANS CROSSES THE MOUNTAINS DURING THE OVERNIGHT. NOT CONFIDENT ENOUGH ON EXACT TIMING OF TSRA...THUS LEAVING OUT OF TAFS ATTM. MORE CONFIDENT ON INCREASING CLOUDS AND INCREASING COVERAGE OF SHOWERS WITH POTENTIAL FOR MVFR CIGS PER INCREASING UPSLOPE EASTERLY FLOW DURING THE OVERNIGHT. MODELS HINT THAT CIGS COULD DROP TO IFR AFTER 06Z/2AM...BUT WOULD LIKE TO SEE INCREASING COVERAGE OF RAIN COOLED AIR BEFORE FORECASTING THE LOW CIGS. PRIMARY CONCERN SATURDAY IS STRONG FRONTAL PASSAGE WHICH IS FORECAST BY ALL MODELS TO OCCUR DURING THE LATE AFTERNOON AND EVENING WITH 40-50KT WESTERLY WINDS 3KFT AGL DEVELOPING BEHIND THE FRONT SATURDAY NIGHT. ANTICIPATING BKN LINE OF SHOWERS/TSTMS TO ACCOMPANY THE FRONT SATURDAY AFTERNOON...FOLLOWED BY PARTIAL CLEARING SATURDAY NIGHT WITH GUSTY WESTERLY WINDS. THESE WINDS ARE EXPECTED TO PERSIST INTO THE DAY SUNDAY BEFORE DIMINISHING. EXPECT MAINLY VFR CONDITIONS SUNDAY INTO MONDAY...HIGH PRESSURE SPREADING ACROSS THE FORECAST AREA. NEXT COLD FRONT IS FORECAST TO ARRIVE WITH POTENTIAL FOR SHOWERS MONDAY EVENING/OVERNIGHT. TIMING OF SHOWERS WITH THIS FRONT A BIT UNCERTAIN BUT COULD SEE PERIODS OF MVFR MONDAY NIGHT AND MAINLY ALONG THE WESTERN SLOPES TUESDAY...OTHERWISE VFR ACROSS THE EAST. && .CLIMATE... AS OF 300 PM EDT FRIDAY... JUNE 29TH RECORD LOWS BLACKSBURG...42 IN 1974 BLUEFIELD....52 IN 1970 DANVILLE.....54 IN 1968 LEWISBURG....49 IN 1981 LYNCHBURG....51 IN 1970 ROANOKE......44 IN 1919 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS OPERATING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL AT LEAST SUNDAY. THE NOAA WEATHER RADIO IN HINTON WV...BROADCASTING ON A FREQUENCY OF 162.425 MHZ...IS OFF THE AIR DUE TO A TELCO PROBLEM. THIRD PARTY TECHNICIANS ARE CURRENTLY WORKING ON THE COMMUNICATION ISSUE. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...FLASH FLOOD WATCH UNTIL 10 AM EDT SATURDAY FOR VAZ007-009>020- 022>024. NC...FLASH FLOOD WATCH UNTIL 10 AM EDT SATURDAY FOR NCZ001-002. WV...FLASH FLOOD WATCH UNTIL 10 AM EDT SATURDAY FOR WVZ042>044-507- 508. && $$ SYNOPSIS...NF NEAR TERM...NF/PM SHORT TERM...DS LONG TERM...DS/WP AVIATION...PM CLIMATE... EQUIPMENT...PM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
605 PM CDT SUN JUN 28 2015 .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 300 PM CDT SUN JUN 28 2015 ANOTHER CLUSTER OF SHOWERS/STORMS TRACKING SOUTHWARD ACROSS THE REGION AT MID AFTERNOON...BEING DRIVING BY AN UPPER LEVEL DISTURBANCE. SOME INSTABILITY HAS DEVELOPED - ESPECIALLY WEST WHERE SUN BROKE THROUGH THE CLOUDS. ABOUT 1000 SBCAPE VIA THE RAP. HOWEVER...HRRR/RAP BUFKIT SOUNDINGS SHOW A VERY SKINNY CAPE PROFILE...PROHIBITIVE OF STRONG UPDRAFTS. WEAK SHEAR ALSO WOULDN/T SUPPORT UPDRAFTS. A FEW STRONGER STORMS CAN/T BE RULED OUT...BUT DON/T SEE A SEVERE RISK AT THIS TIME. LOOKS MORE LIKE HEAVY DOWNPOURS AND LIGHTNING. PERHAPS HAIL UP TO 1/2 INCH. MOST OF THE ACTIVITY SHOULD DIE OFF BY LATE EVENING WITH THE LOSS OF THE DAYTIME HEATING. ANOTHER SHORTWAVE TROUGH IS SLATED TO DROP ACROSS THE WESTERN RIDGE...DIVING SOUTHEAST ACROSS THE UPPER MISSISSIPPI RIVER VALLEY MONDAY AFTERNOON/EVENING. APPROX 100 KT 300 MB JET STREAK HELPING THIS SHORTWAVE ALONG...AND WILL ALSO ENHANCE ITS LIFT IN ITS LEFT EXIT REGION. DECENT FRONTOGENETIC FORCING LEADS THE SHORTWAVE INTO THE REGION. WITH SOME MORNING SUN - MORESO TO THE WEST - INSTABILITY WILL BUILD AHEAD OF THE APPROACHING SHORTWAVE...AS MUCH AS 2000 J/KG OF SBCAPE. WIND SHEAR IS A BIT HEALTHIER COMPARED TO TODAY...ALTHOUGH DEEPER AND STRONGER OVER WESTERN MN. LOCALLY 30-40 KTS OF 0-6 KM SHEAR PROGGED BY THE NAM/GFS...WITH 20-30 KTS IN THE 0- 3 KM LAYER. STRONGEST OVER NORTHEAST IA/SOUTHEAST MN. CAPE PROFILE VIA GFS BUFKIT SOUNDINGS RATHER ANEMIC BUT THE NAM SHOWS SOMETHING A BIT MORE SUPPORTIVE OF STRONGER UPDRAFTS. CAN/T RULE OUT A FEW STRONG TO SEVERE STORMS AS A RESULT. SPC UPGRADED DAY2 OUTLOOK TO INCLUDE A SLIGHT RISK FOR MUCH OF THE LOCAL AREA...AND CAN/T QUIBBLE WITH THAT. THE MAIN QUESTION WILL BE IF THE SHORTWAVE CAN GET HERE IN TIME TO TAP INTO THE INSTABILITY. FOR TUE...THE SHORTWAVE LINGERS ACROSS EASTERN WI WITH A NORTH-SOUTH RUNNING SFC FRONT RESTING ALONG THE LAKE MICHIGAN SHORELINE. ENOUGH LIFT AND SATURATION FOR SOME SHOWER/ISOLD STORM DEVELOPMENT FOR THE EASTERN 1/2 OF WISCONSIN. DEPENDING ON HOW FAR EAST THE SHORTWAVE MAKES IT...COULD HAVE SOME RAIN CHANCES FOR PARTS OF WESTERN WI. WILL KEEP THE SMALL CHANCES FOR THE WI PORTION OF THE FORECAST AREA WITH THIS IN MIND. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 300 PM CDT SUN JUN 28 2015 MODELS REMAIN IN GOOD AGREEMENT WITH KEEPING THE REGION UNDER NORTHWEST FLOW INTO NEXT WEEKEND...ALTHOUGH THEY SHOW SOME FLATTENING LATER IN THE WEEK AS THE WEST COAST RIDGE BECOMES LESS AMPLIFIED. VARIOUS SHORTWAVES WILL MOVE ALONG THE FLOW AND COULD INTERACT WITH AFTERNOON INSTABILITY TO PRODUCE SHOWERS/STORMS ACROSS THE REGION. BUT THERE ARE DIFFERENCES IN THE MODELS ON TIMING AND PLACEMENT OF THE FEATURES...GENERALLY FAVORING KEEPING THE PERTURBATIONS SOUTHWEST OR NORTH OF THE LOCAL AREA. OUT OF ALL THE DAYS...WED HOLDS PERHAPS THE BEST CHANCE FOR ANOTHER ROUND OF SHOWERS/STORMS...WITH THE GFS/ECMWF DROPPING ONE OF THOSE SHORTWAVES THROUGH THE FORECAST AREA. THE GEM KEEPS IT WEST WITH THE NAM LEANING THAT WAY. NOT A LOT OF CONSISTENCY BETWEEN OR WITHIN THE MODELS IN THIS TIME FRAME. OVERALL...WILL CONTINUE THE SMALL RAIN CHANCES THROUGH MUCH OF THE 7 DAY FORECAST PERIOD DUE TO THE MODEL DIFFERENCES AND TYPE OF FLOW WE ARE IN. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 605 PM CDT SUN JUN 28 2015 CURRENT AREA OF SHOWERS AND STORMS IS MAINLY WEST OF THE MISSISSIPPI RIVER AND EXPECT THAT MOST OF THIS ACTIVITY WILL MISS KLSE SO WILL ONLY SHOW A VCSH FOR EARLY THIS EVENING. THE RAIN MOVING THROUGH KRST SHOULD BE VERY CLOSE TO BEING PAST THE AIRPORT BY 00Z SO WILL ONLY SHOW SOME LIGHT RAIN WITH VFR CONDITIONS. THIS ACTIVITY IS EXPECTED TO DIE OFF BY THE MIDDLE OF THE EVENING AS THE CAPE DIMINISHES AND THE FORCING FROM THE SHORT WAVE TROUGH MOVING THROUGH SHIFTS OFF TO THE SOUTHEAST. BASED ON SATELLITE TRENDS...THE SKIES SHOULD THEN QUICKLY CLEAR OUT WHICH RAISES THE CONCERN FOR FOG OVERNIGHT. KLSE DID RECEIVE SOME LIGHT RAIN EARLY THIS MORNING BUT HAS NOT HAD ANY DURING THE DAY. WITH ALL THE CLOUDS...THIS LOW LEVEL MOISTURE SHOULD HAVE REMAINED IN PLACE TO HELP WITH FOG FORMATION...BUT THE 28.21Z RAP FORECAST SOUNDING SUGGESTS THAT IF SATURATION OCCURS AT THE SURFACE IT WILL BE VERY LATE AND NOT LAST LONG. WILL MAINTAIN THE FOG TRENDS FROM THE PREVIOUS FORECAST...BUT CONCERNED THAT IF THE RAP IS CORRECT THAT THE VISIBILITY MAY NOT GET AS LOW AS THE FORECAST SHOWS. THE PROBABILITY FOR FOG AT KRST HAS INCREASED WITH THE LATE AFTERNOON RAINS AND HAVE INTRODUCED A PERIOD OF IFR CONDITIONS LATE TONIGHT. THE FOG SHOULD DISSIPATE BY MID MORNING MONDAY WITH VFR CONDITIONS FOR THE REST OF THE DAY. ANY SHOWERS AND STORMS FROM THE NEXT SYSTEM SHOULD HOLD OFF UNTIL MONDAY EVENING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1154 PM CDT FRI JUN 26 2015 .SHORT TERM...(TONIGHT THROUGH SUNDAY) ISSUED AT 215 PM CDT FRI JUN 26 2015 CONVECTION FIRING IN A BROAD REGION OF UNSTABLE AIR...JUST NEEDING A FOCUS TO GET IT GOING. LATEST RADAR IMAGERY PLACES ONE CLUSTER DIVING SOUTH ACROSS CENTRAL MN IS TIED TO A BIT OF UPPER LEVEL ENERGY. OVER IA INTO NORTHERN ILL IS CO-LOCATED WITH THE BASE OF THE UPPER LEVEL TROUGH. ELSEWHERE...ENHANCED CU AND SOME ISOLATED SHOWERS WERE THE RULE. HEADING INTO THE EVENING...EXPECT BOTH AREAS OF PCPN TO CONTINUE - DYING OUT WITH THE LOSS OF THE DAYTIME HEATING. BUT...THE RAP AND NAM12 SUGGEST A SOUTHWEST-NORTHEAST RUNNING BOUNDARY ACROSS THE FORECAST AREA...WHICH COULD SERVE AS A TRIGGER FOR A SCATTERED LINE OF SHOWERS/STORMS LATE AFTERNOON/EARLY EVENING. WILL MONITOR AND INCREASE POPS IF THIS BECOMES LIKELY. UPPER LEVEL SHORTWAVE TROUGH SLATED TO MOVE ACROSS THE AMPLIFIED RIDGE OVER THE WEST...SPINNING ACROSS THE UPPER MISSISSIPPI RIVER VALLEY ON SUNDAY. DECENT QG CONVERGENCE WITH THIS FEATURE...ALONG WITH LOW LEVEL WARMING - ALTHOUGH MOSTLY CENTERED OVER IA. 300 MB JET STREAK LOOKS TO ENHANCE THE LIFT. PLENTY OF DYNAMICS AND ENOUGH SATURATION FOR AN AREA OF SHOWERS AND THUNDERSTORMS...AND ALL THE MODELS HAVE SAID AS MUCH OVER THE PAST FEW DAYS. QUESTIONS ARISE WITH THE TIMING OF THE SHORTWAVE/AREAS OF RAIN AND HOW MUCH INSTABILITY/SHEAR WILL BE PRESENT. 12Z GFS/NAM RUNS BRING THE SHORTWAVE IN BY 12Z SUN...WITH PCPN LIKELY FOR AT LEAST THE WESTERN 1/2 OF THE FORECAST AREA BY THAT TIME. THE PCPN AND TROUGH AXIS THEN SWINGS INTO WESTERN WI FOR SUN AFTERNOON. NOT A LOT OF SHEAR THROUGH THE DAY...MOST OF WHICH LIES IN THE 0-3KM LAYER - ROUGHLY 20-30 KTS. AS ONE WOULD EXPECT...NOT MUCH INSTABILITY AT 12Z SUN MORNING...BUT THE GFS/NAM DEVELOP A RIBBON OF 1500-2000 J/KG SBCAPE ACROSS THE WESTERN 2/3RDS OF THE FORECAST AREA IN THE AFTERNOON. HOWEVER...THIS IS POST THE PCPN SHIELD AND MUCH OF THE DYNAMICS. NOT SURE IT WILL/COULD BE UTILIZED BY THE EXPECTED ONGOING CONVECTION...OR FOR ANY REDEVELOPMENT IN THE WEST. AS A RESULT...BELIEVE THE POTENTIAL FOR ORGANIZED SEVERE WEATHER IS LOW...ALTHOUGH A FEW STRONGER STORMS COULD BE POSSIBLE. ALL IN ALL...SUNDAY LOOKS LIKE A WET DAY...WEST OF THE MISSISSIPPI RIVER IN THE MORNING...EAST IN THE AFTERNOON. .LONG TERM...(MONDAY THROUGH FRIDAY) ISSUED AT 215 PM CDT FRI JUN 26 2015 AFTER SUNDAY...THE GFS/ECMWF HOLD ONTO THE WESTERN RIDGE-EASTERN TROUGH CONFIGURATION FOR MUCH OF THE NEW WEEK...KEEPING THE LOCAL AREA UNDER NORTHWEST FLOW. VARIOUS PERTURBATIONS IN THE UPPER LEVEL LEVEL FLOW WOULD SPIN ACROSS THE UPPER MISSISSIPPI RIVER VALLEY...RESULTING IN PERIODIC RAIN CHANCES. MODEL DIFFERENCES IN PLACEMENT AND TIMING OF THESE BITS OF ENERGY - AS EXPECTED - BUT NONE OF THE SOLUTIONS ARE SUGGESTIVE OF WIDESPREAD...ALL-DAY KIND OF RAIN EVENTS. INSTABILITY AND WIND SHEAR DON/T FAVOR ORGANIZED SEVERE WEATHER AT THIS TIME EITHER. WILL CONTINUE THE BLANKET OF SMALL RAIN CHANCES THROUGH THE PERIOD...REVISING AS THE DETAILS BECOMING CLEARER. WITH THE RELATIVELY COOLER NORTHWEST TRAJECTORY COUPLED WITH CLOUDS/RAIN POTENTIAL...TEMPERATURES SHOULD HOLD NEAR OR BELOW THE SEASONABLE NORMALS. IN ADDITION...NO TO LIMITED TAP INTO GULF MOISTURE DURING THE WEEK SHOULD KEEP HUMIDITIES IN CHECK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1154 PM CDT FRI JUN 26 2015 SKIES HAVE PRETTY MUCH CLEARED OUT THIS EVENING AS HIGH PRESSURE STARTS TO BUILD IN OVER THE REGION. SHOULD BE VFR CONDITIONS THROUGH SATURDAY AS THE HIGH DRIFTS ACROSS THE AREA. SOME POTENTIAL FOR FOG TONIGHT AT KLSE WITH LIGHT WINDS...CLEAR SKIES AND SOME LOW LEVEL MOISTURE FROM THE LITTLE BIT OF RAIN THAT FELL THIS EVENING. TO ACCOUNT FOR THIS...HAVE INCLUDED THE POSSIBILITY OF MVFR VISIBILITY LATE TONIGHT. AS THE HIGH MOVES AWAY FROM THE AREA SATURDAY EVENING...THE WINDS WILL COME AROUND TO THE SOUTH AND THE MID AND HIGH LEVEL CLOUDS WILL START TO INCREASE AHEAD OF THE NEXT APPROACHING SHORT WAVE TROUGH. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION...04
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
107 AM EDT MON JUN 29 2015 .SYNOPSIS... A STATIONARY FRONT WILL DISSIPATE WEST OF THE AREA THROUGH MONDAY. ATLANTIC HIGH PRESSURE WILL RESIDE ACROSS THE AREA WHILE A TROUGH OF LOW PRESSURE PERSISTS INLAND. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... THE FRONT WAS STALLED JUST WEST OF THE FORECAST AREA EARLY THIS MORNING. THIS WILL KEEP THE ENTIRE FORECAST AREA IN THE WARM SECTOR OVERNIGHT. SOME DRIER AIR WILL ADVECT INTO THE WESTERN ZONES LATE...BUT IT WILL REMAIN A WARM AND MOIST NIGHT WITH LOWS RANGING FROM THE LOWER 70S INLAND TO THE MID 70S AT THE COAST. LAYERED CLOUDS OVER THE REGION...MOST OF THEM IN SOUTH CAROLINA MID TO HIGH BUT PLENTY OF STRATUS WAS NOW DEVELOPING OVER SE GEORGIA. A FEW SPOTS WELL INLAND OVER PARTS OF ALLENDALE... SCREVEN AND JENKINS COUNTY COULD BRIEFLY DROP INTO THE UPPER 60S BEFORE SUNRISE MONDAY...ESPECIALLY IF THE BOUNDARY LAYER DECOUPLES. MEASURABLE RAINFALL HAS ENDED. AN ISOLATED SHOWER CAN NOT BE COMPLETELY RULED OUT ACROSS THE COASTAL COUNTIES WHERE PWATS WILL REMAIN ABOVE 1.5 INCHES. LOWER POPS BELOW 15 PERCENT ACROSS THE COASTAL COUNTIES THROUGH THE NIGHT WITH DRY CONDITIONS FARTHER INLAND WHERE PWATS ARE FORECAST TO DROP TO 0.80 TO 1 INCH BY SUNRISE. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY/... MONDAY...A STALLED FRONT ACROSS THE AREA WILL DISSIPATE THROUGH THE DAY ALLOWING ATLANTIC HIGH PRESSURE TO RETURN. PROXIMITY TO THE BOUNDARY AND REMNANT MOISTURE WILL KEEP CHANCES OF SHOWERS/THUNDERSTORMS IN THE FORECAST ALONG COASTAL LOCATIONS AND OVER THE NEARSHORE WATERS. HIGH TEMPERATURES WILL RANGE FROM UPPER 80S AT THE BEACHES TO LOW 90S INLAND. MONDAY NIGHT...CLEARING SKIES AND LIGHT WINDS WILL ALLOW TEMPERATURES TO DROP TO NEAR NORMAL WITH LOWS EXPECTED TO BE IN THE UPPER 60S/LOW 70S. TUESDAY AND WEDNESDAY...THE FORECAST AREA WILL BE POSITIONED ON THE WESTERN PERIPHERY OF ATLANTIC HIGH PRESSURE WITH A PIEDMONT TROUGH BECOMING ESTABLISHED INLAND. ALOFT...A BROAD MID LEVEL TROUGH WILL ENCOMPASS THE EASTERN HALF OF THE COUNTRY. SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH WILL CROSS THE SOUTHEAST STATES AIDING IN THE DEVELOPMENT OF SHOWERS AND THUNDERSTORMS. CURRENT POP SCHEME FEATURES SLIGHT CHANCE/CHANCE POPS DURING PEAK HEATING EACH AFTERNOON. OVERALL SEVERE THREAT LOOKS RATHER LOW GIVEN MARGINAL INSTABILITY AND UNIMPRESSIVE MID LEVEL LAPSE RATES. HIGH TEMPERATURES WILL MAINLY BE IN THE LOW 90S...WITH LOW TEMPERATURES IN THE LOW/MID 70S. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A QUASI-ZONAL FLOW WILL AFFECT THE REGION WEDNESDAY NIGHT THROUGH FRIDAY AS A LONGWAVE TROUGH REMAINS POSITIONED TO THE NORTHWEST. HEIGHTS WILL BE INCREASING OVER THE INDEPENDENCE DAY WEEKEND AS THE UPPER RIDGE RESTRENGTHENS OVER THE SOUTHEAST. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE A BIT HIGHER THURSDAY INTO FRIDAY DUE TO WEAKER CAPPING. DECREASING COVERAGE EXPECTED OVER THE WEEKEND AS THE UPPER RIDGE REBUILDS AND MID-LEVELS WARM. HIGHS WILL BE IN THE LOWER 90S LATE WEEK...INCREASING INTO THE LOW/MID 90S OVER THE WEEKEND. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... KSAV...IFR CIGS DEVELOPED PRIOR TO 03Z AND APPEARS TO WANT TO LOCK IN. 00Z NAM AND LATEST RAP SOUNDINGS NOW BOTH INDICATE THE IFR CIGS MAY LINGER. SINCE MORE OBS IN SE GEORGIA WERE NOW REPORTING STRATUS...WE WILL HOLD ONTO THE LOW CIGS OVERNIGHT WITH QUITE A BIT OF UNCERTAINTY AS LOW CLOUD SATELLITE TRACKING MASKED BY EXTENSIVE HIGH CLOUD COVER. AFTER MID MORNING AT THE LATEST...VFR CONDITIONS WILL RETURN WITH VERY MINIMAL CHANCES FOR ANY RAIN THROUGH TONIGHT. KCHS...WE MAY SEE SOME PATCHY MVFR/IFR CIGS AROUND DAYBREAK BUT HELD THE TAFS VFR THROUGH THE CYCLE WITH DRY WEATHER AND MAINLY LIGHT WINDS. EXTENDED AVIATION OUTLOOK...BRIEF FLIGHT RESTRICTIONS POSSIBLE IN AFTERNOON SHOWERS/THUNDERSTORMS TUESDAY THROUGH THURSDAY. && .MARINE... OVERNIGHT...THE STATIONARY FRONT WILL REMAIN WEST OF THE WATERS TONIGHT. THIS WILL KEEP A SOLID SOUTHWEST FLOW IN TACT. A MODEST NOCTURNAL SURGE IS EXPECTED WITH WINDS UP TO 15 KT OUT TO 20 NM AND A SOLID 15 TO 20 KT BEYOND. SEAS WILL GENERALLY RANGE 2-3 FT IN THE NEARSHORE WATERS AND UP TO 4 FT IN THE GEORGIA OFFSHORE WATERS. MONDAY THROUGH FRIDAY...ATLANTIC HIGH PRESSURE WILL GENERALLY DOMINATE THE WEATHER PATTERN OVER THE COASTAL WATERS AS A PIEDMONT TROUGH BECOMES ESTABLISHED INLAND. SEA BREEZE CIRCULATIONS AND NOCTURNAL LOW LEVEL JETTING WILL ALLOW SOUTH/SOUTHWEST WINDS TO PEAK 15-20 KT AT TIMES. SMALL CRAFT ADVISORIES ARE NOT ANTICIPATED THROUGH THE PERIOD. SEAS WILL BE 2-4 FEET ON AVERAGE. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
448 AM EDT MON JUN 29 2015 .SYNOPSIS... ISSUED AT 446 AM EDT MON JUN 29 2015 LOW PRESSURE WILL DRIFT ACROSS NORTHERN INDIANA TODAY...BRINGING YET ANOTHER CHANCE FOR SHOWERS AND A FEW STORMS. AS THE LOW MOVES AWAY THIS EVENING A BRIEF DRY PERIOD IS IN STORE PRIOR TO THE ARRIVAL OF THE NEXT CHANCE FOR RAIN ON TUESDAY. HIGHS TODAY WILL BE IN THE LOWER 70S WITH LOWS TONIGHT DROPPING INTO THE UPPER 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 446 AM EDT MON JUN 29 2015 THE TRAIN OF WAVES CONTINUES WITH ONE UPPER LEVEL SYSTEM NOW PASSING ACROSS THE SOUTHERN GREAT LAKES/N OHIO VALLEY WITH SCATTERED TO NUMEROUS SHOWERS AND A FEW STORMS. COVERAGE SO FAR HAS STRUGGLED ACROSS THE FORECAST AREA WITH SOME SMALL AREAS OF SHOWERS MOVING GENERALLY ALONG AND SOUTH OF US 24. TRENDS TO THE WEST WOULD SUGGEST THAT RAINFALL CHANCES MAY DIMINISH QUICKLY THIS MORNING WITH THE MAIN FOCUS ON SE/E SECTIONS THAT HAVE SEEN TOO MUCH RAIN ALREADY. A FEW OF THE HIGH RES MODELS PRINT OUT THREE QUARTERS TO OVER AN INCH OF RAIN (6Z RAP WENT TO EXTREME OF SWATH OF 1 TO 2 INCHES OF RAIN FROM GRANT COUNTY NE TO FT WAYNE). GIVEN LIKELIHOOD OF DEFORMATION ZONE OF MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL SETTING UP IN EASTERN AREAS...RAINFALL AMOUNTS COULD BE REALIZED. HOWEVER...PWATS NOT AS HIGH AS PAST SYSTEMS AND WHILE BRIEFLY SLOWING THE SYSTEM WILL BE SOMEWHAT MORE PROGRESSIVE IN NATURE. WITH MUCH OF THE AREA OF CONCERN ALREADY COVERED BY AREAL FLOOD WARNING THAT WILL LIKELY BE EXTENDED HOISTING A WATCH FOR THOSE AREAS SERVES NO PURPOSE. IN LOCATIONS FURTHER SOUTHWEST...ARGUMENT COULD BE MADE TO HOIST THE WATCH...BUT EQUAL ARGUMENT (AND MAYBE BETTER APPROACH) COULD BE TO EXPAND/ISSUE AREAL FLOOD WARNING VS A FLOOD WATCH. WILL MONITOR TRENDS NEXT COUPLE OF HOURS. TEMPERATURES WERE LOWERED SOMEWHAT TODAY WITH CLOUDS AND PRECIP BUT MAY STILL BE TOO WARM. BEST POTENTIAL FOR HEATING MAY BE IN SW AREAS THAT COULD SEE SOME BREAKS IN THE CLOUDS BY LATE AFTERNOON AS THE SFC LOW PASSES OVERHEAD. PRECIP MAY LINGER IN THE EAST INTO THE EVENING BUT SHOULD PUSH OUT RATHER QUICKLY AS SMALL AREA OF SUBSIDENCE SHIFTS IN LATE EVENING INTO PART OF THE OVERNIGHT HOURS BEFORE THE NEXT WAVE APPROACHES. KEPT SLGT CHC POPS THROUGH THE NIGHT WITH INCREASE IN THE WEST TOWARDS DAYBREAK. LOWS WILL DROP INTO THE UPPER 50S TO LOWER 60S. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 446 AM EDT MON JUN 29 2015 SHRTWV OVER MANITOBA THIS MORNING EXPECTED TO DROP SE TO NE IL BY 12Z TUE THEN SWING EAST THROUGH BASE OF TROF ACROSS NRN INDIANA DURING THE DAY. MODELS SUGGEST FAIRLY STRONG FORCING AND WK-MOD INSTABILITY WILL ACCOMPANY THIS SYSTEM TUE...SO SCT-NUMEROUS SHOWERS/TSTMS LIKELY. SFC CDFNT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO MOVE SLOWLY SE ACROSS OUR CWA TUE NGT-WED NGT AS ANOTHER SHRTWV MOVES SE FROM THE NRN PLAINS TO THE LWR OH VALLEY. THIS MAY CAUSE SCT SHOWERS/TSTMS TO CONT IN THE CWA WITH BEST CHANCES ACROSS SRN PORTIONS OF THE AREA IN CLOSEST PROXIMITY TO THE SLOW MOVG SFC BOUNDARY. CURRENT AMPLIFIED UPR AIR PATTERN WITH STRONG RIDGE IN WRN NORTH AMERICA AND TROF FROM HUDSON BAY THROUGH THE GRTLKS EXPECTED TO TRANSITION TO A MORE ZONAL FLOW LATE IN THE PERIOD AS GULF OF ALASKA CLOSED LOW GETS KICKED EAST INTO WRN CANADA WKNG RIDGE IN THAT AREA. STILL... A WK BROAD TROF EXPECTED TO PERSIST ACROSS THE GRTLKS THROUGH THE PERIOD WITH AN E-W ORIENTED STNRY SFC BOUNDARY LIKELY CONTG JUST SOUTH OF OUR CWA. ALSO APPEARS THAT SOME WK SHRTWVS WILL TOP WRN RIDGE AND MOVE SE TOWARD BASE OF THE BROAD TROF OVER OUR AREA IN THIS TIMEFRAME. THUS... A SMALL CHANCE OF SHOWERS/TSTMS CONTS FOR MUCH OF THE LONG TERM PERIOD. THIS SCENARIO ALSO SUPPORTS A CONTINUATION OF TEMPS SLIGHTLY BLO NORMAL THROUGH THIS PERIOD... THOUGH A WARMUP EXPECTED NEXT WEEKEND AS FLOW ALOFT BECOMES MORE ZONAL AND LOW LEVEL SOUTHERLY WINDS RETURN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1245 AM EDT MON JUN 29 2015 ONLY MINOR CHANGES BEING MADE TO THE FIRST 6 HOURS OR SO TO ADD MENTION OF VFR SHOWERS AT KSBN AS SHOWER ACTIVITY HAS BEEN TRYING TO INCREASE SOMEWHAT BUT STILL ON THE LIGHT SIDE. ALL SIGNS POINT TOWARDS MVFR AND POSSIBLE IFR CONDITIONS THROUGH THE DAY AS LOW PRESSURE DRIFTS ACROSS CENTRAL INDIANA TODAY. CAN`T RULE OUT A STRAY THUNDERSTORM...ESPECIALLY KFWA BUT NOT WORTHY OF TAF MENTION WITH GREATER CONFIDENCE SOUTH OF BOTH TAF SITES. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...FISHER SHORT TERM...FISHER LONG TERM...JT AVIATION...FISHER VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
449 AM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 424 AM CDT MON JUN 29 2015 LOOKING AT WEB CAMS AND OBSERVATION SITES HAS INDICATED THE FOG HAS WORSENED AND MANY LOCATIONS ARE SOCKED IN WITH VISIBILITIES OF 1/4 MILE OR LESS. THEREFORE...I HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA UNTIL 9 AM. IF THE FOG DISSIPATES SOONER THAN THE ADVISORY CAN BE CANCELLED. && .SYNOPSIS... ISSUED AT 345 AM CDT MON JUN 29 2015 LIGHT TO CALM WINDS AND WET GROUND HAS LED TO THE DEVELOPMENT OF GROUND FOG ACROSS MUCH OF THE CWA. LOOKING AT WEB CAMS AND OBSERVATIONS THE VISIBILITIES WERE HIGHLY VARIABLE AND A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THIS SITUATION. 3 AM TEMPERATURES WERE IN THE MID 50S NORTH TO MID 60S SOUTH ACROSS THE CWA. A WEAK VORT MAX IN WI WAS CAUSING A FEW SHOWERS THERE WHILE A STRONGER SHORT WAVE WAS SEEN ON WATER VAPOR LOOPS IN MANITOBA AND DROPPING SOUTHWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON JUN 29 2015 FORECAST FOCUS ON RAIN CHANCES. TODAY...AREAS OF FOG SHOULD DISSIPATE BY 8 AM OR SO AND THEN ATTENTION TURNS TO CHANCES FOR SHOWERS AND THUNDERSTORMS. WILL MENTION SLIGHT CHANCES FOR SHOWERS THIS MORNING AND THEN INCREASE POPS THIS AFTERNOON FOR THUNDERSTORMS. FORECAST SOUNDINGS INDICATE WE REACH CONVECTIVE TEMPERATURES BY AROUND NOON WITH STEEPENING LAPSE RATES...AND NO CAP IN PLACE. THE HRRR INDICATES SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF THE CWA THIS AFTERNOON WHILE OTHER MODELS ARE FAIRLY SIMILAR. THE SEVERE HAILERS SHOULD REMAIN NORTH ACROSS MN AND WESTERN WI AIDED BY THE DECENT MANITOBA WAVE AND COLDER AIR ALOFT. HOWEVER...SOME OF THESE STORMS MAY DRIFT INTO NORTHEAST IA LATER THIS AFTERNOON AND EARLY EVENING WITH THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS. SHEAR IS WEAK AND SBCAPES ARE PROGGED AT 1000-2000 J/KG. HOWEVER...IF TEMPERATURES CAN WARM MORE THAN EXPECTED THAN AN ISOLATED LARGE HAIL IS NOT OUT OF THE QUESTION WITH FREEZING LEVELS AT 11K FT. SPC HAS A MARGINAL RISK FOR THE POTENTIAL FOR STRONGER STORMS IN OUR NW CWA. THERE SHOULD BE PLENTY OF CLOUD COVER AGAIN WITH SOME PEEKS OF SUNSHINE. THIS WILL KEEP AFTERNOON TEMPERATURES IN THE 70S AT MOST LOCATIONS. TONIGHT...AT LEAST SCATTERED SHOWERS AND STORMS THIS EVENING WILL GRADUALLY DIMINISH WITH LOSS OF HEATING LATER THIS EVENING. THEN WILL CARRY SMALL POPS AFTER MIDNIGHT AS THE NAM/GFS INDICATE SOME LINGERING QPF WITH ANY WEAK VORT MAX IN THE DEEP NORTHWEST FLOW. HOWEVER...THE ECMWF IS COMPLETELY DRY THIS EVENING AND OVERNIGHT. MINIMUM TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON JUN 29 2015 NOT MUCH CHANGE IN THE OVERALL PATTERN WITH NORTHWEST FLOW ALOFT TO PREVAIL THROUGH MUCH OF THE PERIOD KEEPING TEMPS NEAR TO BELOW NORMAL WHILE ALSO LIMITING ANY ORGANIZED SEVERE POTENTIAL. WILL SEE PERIODIC RAIN CHANCES AS SEVERAL UPPER LEVEL DISTURBANCES TRANSVERSE THE REGION. ONE SUCH DISTURBANCE OFF THE PACIFIC NW COAST EARLY THIS AM FAIRLY VIGOROUS LOOKING PER SATELLITE REPRESENTATION. THIS ENERGY WILL CREST THE WESTERN HEAT DOME NEXT 24 HOURS THEN HEAD SE AND INTERACT WITH IMPRESSIVE LOW LEVEL MOISTURE CONVERGENCE AND BAROCLINIC ZONE (SQUEEZED BETWEEN DRIER EASTERLY FLOW OFF LAKE MI AND ADVECTION OF DRIER AIR WITH SOUTHWEST FLOW OFF EASTERN ROCKIES INTO KS) FOR WIDESPREAD SHOWERS AND STORMS WITH POTENTIAL FOR HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE MAIN CHALLENGE IS JUST WHERE DOES THIS BATTLE ZONE AND HIGHER PROBABILITIES OF PRECIP AND HEAVY RAIN SET UP. LAST SEVERAL RUNS OF GFS TRENDING FROM SOUTH OF I-70 TO NEAR THE IA/MO BORDER CLOSER TO LAST FEW RUNS OF NAM. MEANWHILE...THE ECMWF IS A BIT STRONGER WITH THE GREAT LAKES HIGH AND CONSEQUENTLY WITH THE DRIER EASTERLY FLOW... AND IS ALSO SLOWER WITH MAIN SURGE OF MOISTURE FOCUSING MORE LATER WEDNESDAY AND WEDNESDAY NIGHT NEAR THE FAR SOUTHERN CWA AND ESPECIALLY JUST SOUTH/WEST OF CWA. GIVEN THE STRENGTH OF FORCING WOULD ANTICIPATE THE THREAT FOR RAINFALL AMOUNTS OF 1-2+ INCHES WHERE THIS SETS UP AND WILL NEED TO BE WATCHED VERY CAREFULLY FOR SOUTHERN CWA WHERE GROUND IS SATURATED AND RIVER LEVELS HIGH FROM SEVERAL ROUNDS OF HEAVY RAINFALL WITHIN THE PAST WEEK OR SO. GIVEN THE MODEL CONSISTENCY AND TIMING ISSUES I HAVE KEPT POPS IN THE CHANCE CATEGORY FOR NOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGHEST FAR SOUTH. IN THE WAKE OF THIS SYSTEM WOULD ANTICIPATE 24+ HRS OF DRY AND PLEASANT WEATHER THURSDAY POSSIBLY INTO FRIDAY WITH SURFACE RIDGING AND EASTERLY FLOW. THEN...OPERATIONAL GFS AND MANY OF GFS ENSEMBLE MEMBERS ALONG WITH HI-RES ECMWF SUGGEST ANOTHER DISTURBANCE ACCOMPANIED BY RAIN CHANCES ESPECIALLY THE SOUTHERN CWA DEVELOPING FRIDAY AND LINGERING INTO FRIDAY NIGHT. IF THIS TIMING HOLDS THEN HAVE AN OPPORTUNITY TO SNEAK IN A DRY AND SEASONABLE 4TH OF JULY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 449 AM CDT MON JUN 29 2015 WIDESPREAD LIFR CONDS IN FG TIL 14Z/29. THEN VFR CONDS WITH SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. NORTHWEST WINDS AROUND 10 KNOTS OR LESS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BENTON- BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA- IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA- MUSCATINE-SCOTT-VAN BUREN-WASHINGTON. IL...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BUREAU- CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH- MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE. MO...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR CLARK- SCOTLAND. && $$ UPDATE...HAASE SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
425 AM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 424 AM CDT MON JUN 29 2015 LOOKING AT WEB CAMS AND OBSERVATION SITES HAS INDICATED THE FOG HAS WORSENED AND MANY LOCATIONS ARE SOCKED IN WITH VISIBILITIES OF 1/4 MILE OR LESS. THEREFORE...I HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA UNTIL 9 AM. IF THE FOG DISSIPATES SOONER THAN THE ADVISORY CAN BE CANCELLED. && .SYNOPSIS... ISSUED AT 345 AM CDT MON JUN 29 2015 LIGHT TO CALM WINDS AND WET GROUND HAS LED TO THE DEVELOPMENT OF GROUND FOG ACROSS MUCH OF THE CWA. LOOKING AT WEB CAMS AND OBSERVATIONS THE VISIBILITIES WERE HIGHLY VARIABLE AND A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THIS SITUATION. 3 AM TEMPERATURES WERE IN THE MID 50S NORTH TO MID 60S SOUTH ACROSS THE CWA. A WEAK VORT MAX IN WI WAS CAUSING A FEW SHOWERS THERE WHILE A STRONGER SHORT WAVE WAS SEEN ON WATER VAPOR LOOPS IN MANITOBA AND DROPPING SOUTHWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON JUN 29 2015 FORECAST FOCUS ON RAIN CHANCES. TODAY...AREAS OF FOG SHOULD DISSIPATE BY 8 AM OR SO AND THEN ATTENTION TURNS TO CHANCES FOR SHOWERS AND THUNDERSTORMS. WILL MENTION SLIGHT CHANCES FOR SHOWERS THIS MORNING AND THEN INCREASE POPS THIS AFTERNOON FOR THUNDERSTORMS. FORECAST SOUNDINGS INDICATE WE REACH CONVECTIVE TEMPERATURES BY AROUND NOON WITH STEEPENING LAPSE RATES...AND NO CAP IN PLACE. THE HRRR INDICATES SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF THE CWA THIS AFTERNOON WHILE OTHER MODELS ARE FAIRLY SIMILAR. THE SEVERE HAILERS SHOULD REMAIN NORTH ACROSS MN AND WESTERN WI AIDED BY THE DECENT MANITOBA WAVE AND COLDER AIR ALOFT. HOWEVER...SOME OF THESE STORMS MAY DRIFT INTO NORTHEAST IA LATER THIS AFTERNOON AND EARLY EVENING WITH THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS. SHEAR IS WEAK AND SBCAPES ARE PROGGED AT 1000-2000 J/KG. HOWEVER...IF TEMPERATURES CAN WARM MORE THAN EXPECTED THAN AN ISOLATED LARGE HAIL IS NOT OUT OF THE QUESTION WITH FREEZING LEVELS AT 11K FT. SPC HAS A MARGINAL RISK FOR THE POTENTIAL FOR STRONGER STORMS IN OUR NW CWA. THERE SHOULD BE PLENTY OF CLOUD COVER AGAIN WITH SOME PEEKS OF SUNSHINE. THIS WILL KEEP AFTERNOON TEMPERATURES IN THE 70S AT MOST LOCATIONS. TONIGHT...AT LEAST SCATTERED SHOWERS AND STORMS THIS EVENING WILL GRADUALLY DIMINISH WITH LOSS OF HEATING LATER THIS EVENING. THEN WILL CARRY SMALL POPS AFTER MIDNIGHT AS THE NAM/GFS INDICATE SOME LINGERING QPF WITH ANY WEAK VORT MAX IN THE DEEP NORTHWEST FLOW. HOWEVER...THE ECMWF IS COMPLETELY DRY THIS EVENING AND OVERNIGHT. MINIMUM TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON JUN 29 2015 NOT MUCH CHANGE IN THE OVERALL PATTERN WITH NORTHWEST FLOW ALOFT TO PREVAIL THROUGH MUCH OF THE PERIOD KEEPING TEMPS NEAR TO BELOW NORMAL WHILE ALSO LIMITING ANY ORGANIZED SEVERE POTENTIAL. WILL SEE PERIODIC RAIN CHANCES AS SEVERAL UPPER LEVEL DISTURBANCES TRANSVERSE THE REGION. ONE SUCH DISTURBANCE OFF THE PACIFIC NW COAST EARLY THIS AM FAIRLY VIGOROUS LOOKING PER SATELLITE REPRESENTATION. THIS ENERGY WILL CREST THE WESTERN HEAT DOME NEXT 24 HOURS THEN HEAD SE AND INTERACT WITH IMPRESSIVE LOW LEVEL MOISTURE CONVERGENCE AND BAROCLINIC ZONE (SQUEEZED BETWEEN DRIER EASTERLY FLOW OFF LAKE MI AND ADVECTION OF DRIER AIR WITH SOUTHWEST FLOW OFF EASTERN ROCKIES INTO KS) FOR WIDESPREAD SHOWERS AND STORMS WITH POTENTIAL FOR HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE MAIN CHALLENGE IS JUST WHERE DOES THIS BATTLE ZONE AND HIGHER PROBABILITIES OF PRECIP AND HEAVY RAIN SET UP. LAST SEVERAL RUNS OF GFS TRENDING FROM SOUTH OF I-70 TO NEAR THE IA/MO BORDER CLOSER TO LAST FEW RUNS OF NAM. MEANWHILE...THE ECMWF IS A BIT STRONGER WITH THE GREAT LAKES HIGH AND CONSEQUENTLY WITH THE DRIER EASTERLY FLOW... AND IS ALSO SLOWER WITH MAIN SURGE OF MOISTURE FOCUSING MORE LATER WEDNESDAY AND WEDNESDAY NIGHT NEAR THE FAR SOUTHERN CWA AND ESPECIALLY JUST SOUTH/WEST OF CWA. GIVEN THE STRENGTH OF FORCING WOULD ANTICIPATE THE THREAT FOR RAINFALL AMOUNTS OF 1-2+ INCHES WHERE THIS SETS UP AND WILL NEED TO BE WATCHED VERY CAREFULLY FOR SOUTHERN CWA WHERE GROUND IS SATURATED AND RIVER LEVELS HIGH FROM SEVERAL ROUNDS OF HEAVY RAINFALL WITHIN THE PAST WEEK OR SO. GIVEN THE MODEL CONSISTENCY AND TIMING ISSUES I HAVE KEPT POPS IN THE CHANCE CATEGORY FOR NOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGHEST FAR SOUTH. IN THE WAKE OF THIS SYSTEM WOULD ANTICIPATE 24+ HRS OF DRY AND PLEASANT WEATHER THURSDAY POSSIBLY INTO FRIDAY WITH SURFACE RIDGING AND EASTERLY FLOW. THEN...OPERATIONAL GFS AND MANY OF GFS ENSEMBLE MEMBERS ALONG WITH HI-RES ECMWF SUGGEST ANOTHER DISTURBANCE ACCOMPANIED BY RAIN CHANCES ESPECIALLY THE SOUTHERN CWA DEVELOPING FRIDAY AND LINGERING INTO FRIDAY NIGHT. IF THIS TIMING HOLDS THEN HAVE AN OPPORTUNITY TO SNEAK IN A DRY AND SEASONABLE 4TH OF JULY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1212 AM CDT MON JUN 29 2015 WITH RECENT RAINFALL...LIGHT WINDS AND SOME CLEARING...FOG IS A GOOD BET OVERNIGHT. HAVE GONE WITH PERIODS OF IFR CEILINGS AND VISIBILITIES DURING THE EARLY MORNING. THE NEXT SYSTEM WILL ARRIVE LATE MONDAY AFTERNOON AND EVENING WITH HIGHEST COVERAGE OF SHOWERS AND STORMS NEAR OR AFTER 00Z MONDAY EVENING. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BENTON- BUCHANAN-CEDAR-CLINTON-DELAWARE-DES MOINES-DUBUQUE-HENRY IA- IOWA-JACKSON-JEFFERSON-JOHNSON-JONES-KEOKUK-LEE-LINN-LOUISA- MUSCATINE-SCOTT-VAN BUREN-WASHINGTON. IL...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BUREAU- CARROLL-HANCOCK-HENDERSON-HENRY IL-JO DAVIESS-MCDONOUGH- MERCER-PUTNAM-ROCK ISLAND-STEPHENSON-WARREN-WHITESIDE. MO...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR CLARK- SCOTLAND. && $$ UPDATE...HAASE SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
344 AM CDT MON JUN 29 2015 .SYNOPSIS... ISSUED AT 345 AM CDT MON JUN 29 2015 LIGHT TO CALM WINDS AND WET GROUND HAS LED TO THE DEVELOPMENT OF GROUND FOG ACROSS MUCH OF THE CWA. LOOKING AT WEB CAMS AND OBSERVATIONS THE VISIBILITIES WERE HIGHLY VARIABLE AND A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THIS SITUATION. 3 AM TEMPERATURES WERE IN THE MID 50S NORTH TO MID 60S SOUTH ACROSS THE CWA. A WEAK VORT MAX IN WI WAS CAUSING A FEW SHOWERS THERE WHILE A STRONGER SHORT WAVE WAS SEEN ON WATER VAPOR LOOPS IN MANITOBA AND DROPPING SOUTHWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON JUN 29 2015 FORECAST FOCUS ON RAIN CHANCES. TODAY...AREAS OF FOG SHOULD DISSIPATE BY 8 AM OR SO AND THEN ATTENTION TURNS TO CHANCES FOR SHOWERS AND THUNDERSTORMS. WILL MENTION SLIGHT CHANCES FOR SHOWERS THIS MORNING AND THEN INCREASE POPS THIS AFTERNOON FOR THUNDERSTORMS. FORECAST SOUNDINGS INDICATE WE REACH CONVECTIVE TEMPERATURES BY AROUND NOON WITH STEEPENING LAPSE RATES...AND NO CAP IN PLACE. THE HRRR INDICATES SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF THE CWA THIS AFTERNOON WHILE OTHER MODELS ARE FAIRLY SIMILAR. THE SEVERE HAILERS SHOULD REMAIN NORTH ACROSS MN AND WESTERN WI AIDED BY THE DECENT MANITOBA WAVE AND COLDER AIR ALOFT. HOWEVER...SOME OF THESE STORMS MAY DRIFT INTO NORTHEAST IA LATER THIS AFTERNOON AND EARLY EVENING WITH THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS. SHEAR IS WEAK AND SBCAPES ARE PROGGED AT 1000-2000 J/KG. HOWEVER...IF TEMPERATURES CAN WARM MORE THAN EXPECTED THAN AN ISOLATED LARGE HAIL IS NOT OUT OF THE QUESTION WITH FREEZING LEVELS AT 11K FT. SPC HAS A MARGINAL RISK FOR THE POTENTIAL FOR STRONGER STORMS IN OUR NW CWA. THERE SHOULD BE PLENTY OF CLOUD COVER AGAIN WITH SOME PEEKS OF SUNSHINE. THIS WILL KEEP AFTERNOON TEMPERATURES IN THE 70S AT MOST LOCATIONS. TONIGHT...AT LEAST SCATTERED SHOWERS AND STORMS THIS EVENING WILL GRADUALLY DIMINISH WITH LOSS OF HEATING LATER THIS EVENING. THEN WILL CARRY SMALL POPS AFTER MIDNIGHT AS THE NAM/GFS INDICATE SOME LINGERING QPF WITH ANY WEAK VORT MAX IN THE DEEP NORTHWEST FLOW. HOWEVER...THE ECMWF IS COMPLETELY DRY THIS EVENING AND OVERNIGHT. MINIMUM TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON JUN 29 2015 NOT MUCH CHANGE IN THE OVERALL PATTERN WITH NORTHWEST FLOW ALOFT TO PREVAIL THROUGH MUCH OF THE PERIOD KEEPING TEMPS NEAR TO BELOW NORMAL WHILE ALSO LIMITING ANY ORGANIZED SEVERE POTENTIAL. WILL SEE PERIODIC RAIN CHANCES AS SEVERAL UPPER LEVEL DISTURBANCES TRANSVERSE THE REGION. ONE SUCH DISTURBANCE OFF THE PACIFIC NW COAST EARLY THIS AM FAIRLY VIGOROUS LOOKING PER SATELLITE REPRESENTATION. THIS ENERGY WILL CREST THE WESTERN HEAT DOME NEXT 24 HOURS THEN HEAD SE AND INTERACT WITH IMPRESSIVE LOW LEVEL MOISTURE CONVERGENCE AND BAROCLINIC ZONE (SQUEEZED BETWEEN DRIER EASTERLY FLOW OFF LAKE MI AND ADVECTION OF DRIER AIR WITH SOUTHWEST FLOW OFF EASTERN ROCKIES INTO KS) FOR WIDESPREAD SHOWERS AND STORMS WITH POTENTIAL FOR HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE MAIN CHALLENGE IS JUST WHERE DOES THIS BATTLE ZONE AND HIGHER PROBABILITIES OF PRECIP AND HEAVY RAIN SET UP. LAST SEVERAL RUNS OF GFS TRENDING FROM SOUTH OF I-70 TO NEAR THE IA/MO BORDER CLOSER TO LAST FEW RUNS OF NAM. MEANWHILE...THE ECMWF IS A BIT STRONGER WITH THE GREAT LAKES HIGH AND CONSEQUENTLY WITH THE DRIER EASTERLY FLOW... AND IS ALSO SLOWER WITH MAIN SURGE OF MOISTURE FOCUSING MORE LATER WEDNESDAY AND WEDNESDAY NIGHT NEAR THE FAR SOUTHERN CWA AND ESPECIALLY JUST SOUTH/WEST OF CWA. GIVEN THE STRENGTH OF FORCING WOULD ANTICIPATE THE THREAT FOR RAINFALL AMOUNTS OF 1-2+ INCHES WHERE THIS SETS UP AND WILL NEED TO BE WATCHED VERY CAREFULLY FOR SOUTHERN CWA WHERE GROUND IS SATURATED AND RIVER LEVELS HIGH FROM SEVERAL ROUNDS OF HEAVY RAINFALL WITHIN THE PAST WEEK OR SO. GIVEN THE MODEL CONSISTENCY AND TIMING ISSUES I HAVE KEPT POPS IN THE CHANCE CATEGORY FOR NOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGHEST FAR SOUTH. IN THE WAKE OF THIS SYSTEM WOULD ANTICIPATE 24+ HRS OF DRY AND PLEASANT WEATHER THURSDAY POSSIBLY INTO FRIDAY WITH SURFACE RIDGING AND EASTERLY FLOW. THEN...OPERATIONAL GFS AND MANY OF GFS ENSEMBLE MEMBERS ALONG WITH HI-RES ECMWF SUGGEST ANOTHER DISTURBANCE ACCOMPANIED BY RAIN CHANCES ESPECIALLY THE SOUTHERN CWA DEVELOPING FRIDAY AND LINGERING INTO FRIDAY NIGHT. IF THIS TIMING HOLDS THEN HAVE AN OPPORTUNITY TO SNEAK IN A DRY AND SEASONABLE 4TH OF JULY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1212 AM CDT MON JUN 29 2015 WITH RECENT RAINFALL...LIGHT WINDS AND SOME CLEARING...FOG IS A GOOD BET OVERNIGHT. HAVE GONE WITH PERIODS OF IFR CEILINGS AND VISIBILITIES DURING THE EARLY MORNING. THE NEXT SYSTEM WILL ARRIVE LATE MONDAY AFTERNOON AND EVENING WITH HIGHEST COVERAGE OF SHOWERS AND STORMS NEAR OR AFTER 00Z MONDAY EVENING. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...RP KINNEY
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1203 AM CDT MON JUN 29 2015 .SHORT TERM /TONIGHT/... ISSUED AT 329 PM CDT SUN JUN 28 2015 MAIN CONCERNS SHORT TERM CONTINUE TO BE THE LOW OVER CENTRAL IOWA COMBINED WITH AN UPPER LEVEL VORT MAX OVER IOWA DIGGING SOUTH. WE REMAIN RATHER UNSTABLE WITH MLCAPE 1000-1500J/KG AND SBCAPE OF 2000 TO 2500 J/KG ALONG AN AXIS NEAR AND JUST BEHIND THE TROUGH AT 20Z. SFC CONVERGENCE IS RATHER MEAGER ALONG WITH BULK SHEAR VALUES JUST REACHING 30 TO 35 KTS AT THIS TIME. SOME WEAK CELLS HAVE DEVELOPED FROM NEAR AND EAST OF THE TROUGH AXIS THIS HOUR. EXPECT THIS ACTIVITY TO EXPAND IN COVERAGE THIS AFTERNOON AS THE SYSTEM TRACKS SOUTHEAST. WILL CONTINUE SVR WORDING IN SOUTHEAST/EAST ZONES FOR THE AFTERNOON...THOUGH COVERAGE MAY REMAIN SCT THROUGH 00Z. LCL HEIGHTS EAST OF I35 REMAIN AT 750M (~2450 FT) AND LOW LEVEL CAPE HAS INCREASED TO 100-150 J/KG ALONG THE TROUGH AXIS...SO WILL NEED TO MONITOR ANY STORMS FOR POTENTIAL BRIEF FUNNEL. AS THE SYSTEM PULLS SOUTHEAST THIS EVENING...DIURNAL HEATING WILL DIMINISH AND STORMS WILL DISSIPATE AFTER 01-02Z. HRRR MODEL CONTINUES TO BUBBLE UP ACTIVITY THROUGH THIS TIME. 4KM WRF ALSO SUGGESTS SOME ACTIVITY OVER SOUTHEAST MN MAY EXPAND INTO NORTHEAST IOWA BETWEEN 21 AND 00Z AS WELL. WITH PASSAGE OF THE BOUNDARY...DEW POINTS DROP TO THE UPPER 50S TO LOWER 60S...SO LOWS WILL COOL TO THE LOWER TO MID 60S BY MORNING. PATCHY FOG MAY DEVELOP IN THE CEDAR RIVER VALLEY TOWARD MORNING. .LONG TERM /MONDAY THROUGH SUNDAY/... ISSUED AT 329 PM CDT SUN JUN 28 2015 THERE HAS BEEN LITTLE CHANGE IN FORECAST THINKING FROM PREVIOUS SHIFTS. IOWA WILL REMAIN BENEATH NORTHWESTERLY FLOW ALOFT THROUGH THE END OF THE WEEK...KEEPING TEMPERATURES A LITTLE BELOW SEASONAL NORMALS AND LESSENING THE OVERALL SEVERE WEATHER THREAT. EVEN SO...THINGS WILL REMAIN FAIRLY ACTIVE AS A SERIES OF SHORTWAVE TROUGHS MOVING THROUGH THIS FLOW WILL RESULT IN PERIODIC CHANCES FOR SHOWERS AND THUNDERSTORMS ACROSS OUR FORECAST AREA. THE FIRST SUCH OPPORTUNITY COME LATE ON MONDAY AS A SUBTLE IMPULSE PUSHES AN ATTENDANT WEAK SURFACE TROUGH FROM MINNESOTA DOWN ACROSS IOWA. DESPITE A RELATIVE LACK OF LOW LEVEL MOISTURE...THE BROAD ASCENT AHEAD OF THIS IMPULSE COMBINED WITH FAIRLY STEEP MID LEVEL LAPSE RATES SHOULD BE SUFFICIENT TO GENERATE SOME THUNDERSTORMS...ESPECIALLY ACROSS OUR NORTHERN AND EASTERN COUNTIES...FROM LATE IN THE AFTERNOON INTO EARLY MONDAY NIGHT. HAVE INTRODUCED DETAILS IN TIMING OF POP FORECAST TO ACCOUNT FOR THIS SCENARIO. EVEN AS THIS INITIAL SYSTEM PUSHES OFF TO THE SOUTH ON TUESDAY ANOTHER SHORTWAVE WILL BE APPROACHING FROM THE NORTHWEST...HOWEVER BY TUESDAY NIGHT AND WEDNESDAY A SURFACE RIDGE WILL HAVE BUILT ACROSS THE AREA INCREASING DRY AIR AND SUBSIDENCE IN THE LOWER SECTIONS OF THE ATMOSPHERIC COLUMN. THIS WILL MITIGATE PRECIPITATION CHANCES AND INTENSITY...BUT EVEN SO CHANCE POPS ARE WARRANTED THOUGH NO REAL IMPACTS ARE ANTICIPATED. FINALLY...THE STRONGEST 500 MB TROUGH OF THE WEEK WILL TRAVERSE THE REGION AROUND THURSDAY AND THURSDAY NIGHT IN CONJUNCTION WITH THE AFOREMENTIONED SURFACE HIGH SLIDING OFF TO THE EAST AND A MODEST RETURN OF LOW LEVEL MOISTURE. THIS APPEARS TO BE THE BEST OPPORTUNITY FOR WIDESPREAD PRECIPITATION THIS WEEK...HOWEVER...MODEL CONSISTENCY HAS NOT BEEN THE GREATEST WITH THIS SYSTEM AND THERE ARE STILL TIMING ISSUES SO POPS HAVE BEEN HELD GENERALLY IN THE 40S FOR NOW. IT IS EXPECTED THAT IF THIS SCENARIO HOLDS UP AND WE CAN REFINE THE ARRIVAL OF THE RAIN THEN POPS FOR PART OF THIS TIME FRAME WILL LIKELY INCREASE IN THE COMING DAYS. IN ANY EVENT...THE SEVERE WEATHER THREAT LATER THIS WEEK DOES NOT APPEAR PARTICULARLY NOTEWORTHY. LOOKING INTO THE EXTENDED FORECAST...THERE CONTINUE TO BE INDICATIONS THAT IN WAKE OF THE THURSDAY/THURSDAY NIGHT TROUGH PASSAGE A PERIOD OF DEEP LAYERED RIDGING SHOULD FOLLOW...PROVIDING A COUPLE OF DAYS OF SUNNY AND RELATIVELY COOL WEATHER RIGHT AROUND THE FOURTH OF JULY. OBVIOUSLY ANYONE WITH OUTDOOR HOLIDAY PLANS SHOULD CONTINUE TO MONITOR THE FORECAST THROUGHOUT THE WEEK BUT EARLY SIGNS POINT TO GOOD WEATHER AROUND SATURDAY. && .AVIATION...29/06Z ISSUED AT 1200 AM CDT MON JUN 29 2015 TWO ISSUES THROUGH THE PERIOD WILL BE RADIATION FOG INTO THIS MORNING AND DIURNAL CONVECTION MON AFTERNOON. TEMP/DEWPOINT SPREADS ARE ALREADY QUITE LOW WITH WEAK SFC FLOW AND GRADIENT. CONDITIONS ARE NOT IDEAL WITH OCCASIONAL SCT/BKN MID CLOUDS...BUT WITH MOIST SOIL FROM RECENT RAINS AND ALREADY HIGH RH EXPECT AT LEAST MVFR VSBYS TO DEVELOP...LIKELY IFR OR LESS IN MORE FAVORED SPOTS. ISOLATED TO SCT PEAK HEATING CONVECTION IS ALSO EXPECTED MON AFTERNOON. THIS COULD OCCUR ANYWHERE...BUT ONLY INCLUDED VCSH WORDING IN MORE FAVORED ERN SITES FOR NOW. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...REV LONG TERM...LEE AVIATION...SMALL
AREA FORECAST DISCUSSION
NWS GOODLAND KS
245 AM MDT MON JUN 29 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 241 AM MDT MON JUN 29 2015 NORTHERLY FLOW WILL CONTINUE ACROSS THE PLAINS EAST OF THE ROCKIES AS A RIDGE PERSISTS OVER CENTRAL UTAH. BY WEDNESDAY THE RIDGE RETROGRESSES TO NEVADA. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE AREA TODAY AND TONIGHT. THE HIGH WILL BE REPLACED BY WEAK LOW PRESSURE TUESDAY AND TUESDAY NIGHT. A SURFACE TROUGH WILL SHIFT EAST ACROSS NORTHWEST KANSAS WEDNESDAY FOLLOWED BY HIGH PRESSURE WEDNESDAY NIGHT. PLAN ON CHANCE AND SLIGHT CHANCE POPS ACROSS THE WESTERN PORTION OF THE FA TODAY AND INTO EARLY THIS EVENING. THE NAM AND THE HRRR HAVE A GOOD HANDLE ON STORMS DEVELOPING EARLY THIS MORNING. THE MODELS ARE ALSO INDICATING STORMS THIS AFTERNOON. DYNAMICS SHOULD SLOWLY MOVE TO THE SOUTHWEST FA EARLY THIS EVENING WITH POPS DECREASING TO NIL VALUES. POPS WILL REMAIN NIL OVERNIGHT AND TUESDAY. A SHORTWAVE MOVES THROUGH THE FLOW LATE TUESDAY EVENING. SLIGHT CHANCE LOOKS ON TRACK FOR THAT TIME PERIOD SINCE MOISTURE REMAINS LIMITED. STORMS WEDNESDAY AFTERNOON AND EVENING SHOULD BE CONFINED TO THE FRONTAL BOUNDARY OVER EASTERN COLORADO. ONCE AGAIN MOISTURE IS LIMITED SO SLIGHT CHANCE POPS SHOULD BE APPROPRIATE. MAX TEMPERATURES TODAY AND WEDNESDAY SHOULD RISE INTO THE LOWER 90S IN THE WESTERN FA AND THE UPPER 90S (SIMILAR TO YESTERDAY) IN THE EAST. 850 TEMPERATURES WILL SUPPORT SURFACE TEMPERATURES NEAR 100 DEGREES TUESDAY. APPARENT TEMPERATURES ARE NOT AT HEAT ADVISORY LEVELS BUT THIS WILL NEED TO BE MONITORED. MIN TEMPERATURES SHOULD RANGE FROM 65 TO 70 WITH COOLEST READINGS IN EASTERN COLORADO. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 241 AM MDT MON JUN 29 2015 THE BEST CHANCES FOR PRECIP ARE AT THE START OF THE PERIOD ON THURSDAY AND FRIDAY AS AN UPPER LEVEL TROUGH PASSES ACROSS THE NORTHERN PLAINS AND A FRONTAL BOUNDARY STALLS OUT OVER THE AREA. MEANWHILE...THE UPPER LEVEL RIDGE OVER THE WESTERN HALF OF THE CONUS WILL CONTINUE TO BREAK DOWN. DRIER AIR IS EXPECTED TO MOVE INTO THE NORTHERN PORTION OF THE FORECAST AREA ON FRIDAY AND PROGRESS SOUTH. DRY CONDITIONS LOOK TO PERSIST FOR MUCH OF THE HIGH PLAINS FOR THE WEEKEND AS THE UPPER LEVEL RIDGE SOMEWHAT REBOUNDS ALTHOUGH SOME WEAK DISTURBANCES COULD GENERATE PRECIP CHANCES FOR PARTS OF THE AREA. HIGHS ON THURSDAY ARE EXPECTED TO BE IN THE 80S...COOLING A COUPLE DEGREES ON FRIDAY BEFORE REBOUNDING INTO THE MID 80S TO MID 90S FOR THE WEEKEND AS THE RIDGE REBUILDS. LOWS ARE FORECAST IN THE UPPER 50S TO MID 60S THURSDAY NIGHT AND FRIDAY NIGHT. TEMPERATURES FOR SATURDAY NIGHT LOOK TO BE SLIGHTLY WARMER AND IN THE 60S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1116 PM MDT SUN JUN 28 2015 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD AS WELL. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...JBH AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS JACKSON KY
417 AM EDT MON JUN 29 2015 .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 417 AM EDT MON JUN 29 2015 HIGH AMPLITUDE PATTERN ALOFT WILL MEAN EASTERN CONUS TROUGH WILL DOMINATE OUR WEATHER THROUGH THE SHORT TERM. BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SFC FRONTAL SYSTEM CONTINUES TO MOVE EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. MODELS...AND ESPECIALLY THE HRRR SUGGEST THAT THIS ACTIVITY WILL GRADUALLY WEAKEN AS IT MOVES INTO OUR AREA AROUND DAWN...DUE TO UPPER LEVEL SUPPORT SHEARING OUT. HOWEVER...ADDITIONAL SHORTWAVE ENERGY ALOFT ROUNDING THE BASE OF AN EASTERN CONUS TROUGH SHOULD HELP REGENERATE ACTIVITY THROUGH THE AFTERNOON. SHEAR AND INSTABILITY APPEAR SUFFICIENT FOR THE THREAT OF SOME STRONG TO SEVERE THUNDERSTORMS...MAINLY THROUGH THE AFTERNOON AND EARLY EVENING. BUT THERE ARE SOME LIMITING FACTORS FOR EXAMPLE... CLOUD COVER...LESS THAN IMPRESSIVE MID LEVEL LAPSE RATES...AND FORCING...THE STRONGEST OF WHICH MAY REMAIN FURTHER NORTH AND WEST OF OUR AREA. THEREFORE SEVERE THREAT MAY BE MORE ISOLD IN NATURE WITH RESPECT TO COVERAGE. JUST THE SAME WITH SPC PLACING OUR AREA IN A SLIGHT RISK TODAY WILL CONTINUE TO ADVERTISE THE POTENTIAL. WITH THE APPROACH OF THE SFC TROUGH TO OUR WEST AND MID LEVEL CLOUD COVER CURRENTLY MOVING INTO OUR AREA EXPECT TEMPERATURES TO BEGIN TO REBOUND ACROSS MUCH OF THE AREA BETWEEN NOW AND SUNRISE. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 351 AM EDT MON JUN 29 2015 UPPER LEVEL MODELS CONTINUE TO SUPPORT A LONGWAVE TROUGH ACROSS MUCH OF THE EASTERN CONUS TO START OFF THE PERIOD...KEEPING THE OHIO RIVER VALLEY IN NW FLOW REGIME FROM TUESDAY NIGHT THROUGH FRIDAY. THE AXIS OF THE TROUGH WILL THEN SHIFT DIRECTLY OVER KY AS ANOTHER SHORTWAVE DIGS SOUTHWARD FROM CANADA TO START OFF THE WEEKEND. FINALLY...THE UPPER LEVEL LONGWAVE PATTERN WILL SLOWLY DAMPEN AS WE HEAD INTO THE END OF THE EXTENDED PERIOD SUNDAY INTO MONDAY. HOWEVER...BY THE WEEKEND MODELS SHOW QUITE A BIT OF DISCONTINUITY...SO THE EXACT TIMING AND MAGNITUDE OF THE UPPER LEVEL TROUGH WILL BE SOMEWHAT LOW CONFIDENCE. WITH THE GENERAL NW FLOW...EXPECT SHORTWAVES TO CONTINUE TO TRAVEL SE AND INTO THE OHIO RIVER VALLEY. THIS WILL RESULT IN SEVERAL SURFACE LOW PRESSURE CENTERS AND FRONTAL BOUNDARIES PASSING THROUGH THE REGION...CREATING THE ENERGY AND LIFT TO PRODUCE SHOWERS AND THUNDERSTORMS. AS HAS BEEN THE CASE OVER THE LAST FEW WEEKS...EXPECT MOST WIDESPREAD ACTIVITY TO BE RIGHT ALONG AND JUST AHEAD OF THE FRONTAL BOUNDARY...PEAKING IN SEVERITY DURING THE AFTERNOON AND EARLY EVENING HOURS IN CONJUNCTION WITH THE PEAK HEATING. THE FIRST OF THESE BOUNDARIES WILL BE EXITING TUESDAY NIGHT AS THE NEXT BOUNDARY TO OUR NORTH MAKES A SHIFT SOUTHWARD. THIS SECOND BOUNDARY IS EXPECTED TO MAKE IT INTO THE REGION WEDNESDAY NIGHT...AND ACCORDING TO THE LATEST 00Z RUN OF THE GFS40...SHOULD BECOME STALLED OUT ACROSS THE REGION THROUGH THE DAY FRIDAY AS THE UPPER LEVEL TROUGH BACK-BUILDS ACROSS THE OHIO RIVER VALLEY. ALONG THIS BOUNDARY...EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...WITH ANY UPPER LEVEL WAVES OF ENERGY ENHANCING CHANCES FOR A MCS TO PASS THROUGH THE REGION. THE FRONTAL BOUNDARY WILL FINALLY SHIFT SE OF THE STATE BY FRIDAY EVENING...ASSUMING MODEL TIMING PANS OUT. UNFORTUNATELY...ANOTHER WEAK FRONTAL BOUNDARY WILL HAVE FORMED TO OUR NORTH...AND WE WILL STILL BE IN VERY CLOSE PROXIMITY TO THE EXITING FRONT. UNDER SW FLOW BY THIS POINT...AND STILL IN AN UPPER LEVEL LOW PRESSURE TROUGHING PATTERN...EXPECT LESS ORGANIZED SCATTERED CONVECTION TO CONTINUE INTO THE WEEKEND...WITH BEST CHANCES STILL EXPECTED OVER THE SE CWA CLOSER TO THE EXITING FRONT. BY SUNDAY...MODEL CONFIDENCE IN CONVECTION STARTS TO DECLINE AS THERE IS LITTLE AGREEMENT IN THE PATTERN ALOFT. IF THE GFS IS CORRECT...THE UPPER LEVEL TROUGH WILL BEGIN DAMPENING/WEAKENING... BUT CONTINUED WARM SW FLOW AND A PASSING SHORTWAVE COULD BE THE SPARK FOR YET MORE SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON/EVENING HOURS. BOTH THE ECMWF AND THE GFS DO SUPPORT A LARGE UPPER LEVEL CLOSED LOW PUSHING SOUTH FROM NW CANADA TO CENTRAL CANADA BY LATE IN THE WEEKEND. THIS ENERGY WILL TRANSLATE TO THE SURFACE WITH A STRONG LOW PRESSURE SYSTEM DEVELOPING ACROSS SOUTHCENTRAL CANADA...PULLING A STRONG FRONTAL BOUNDARY WHICH WILL SWEEP ACROSS MUCH OF THE CENTRAL AND EVENTUALLY EASTERN CONUS. EXACT TIMING IS STILL OBVIOUSLY IN LOW CONFIDENCE...BUT IF THIS PANS OUT ANOTHER GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS WILL IMPACT THE REGION AHEAD OF THE FRONTAL ZONE AS WE END THE EXTENDED PERIOD MONDAY. WITH A NW FLOW REGIME...COOLER AIR WILL BE PULLED IN FROM CANADA TO START OUT THE EXTENDED PERIOD. THEN AS THE TROUGH BACK-BUILDS AND GENERALLY SW FLOW TAKES HOLD DURING A PORTION OF THE PERIOD...WE WILL ACTUALLY CONTINUE TO PULL COOLER AIR IN FROM THE NORTH...AS WINDS BECOME MORE NW JUST TO OUR WEST. THIS...IN CONJUNCTION WITH CLOUD COVER AND POTENTIAL RAIN...WILL KEEP TEMPERATURES MODERATED THROUGH MUCH OF THE EXTENDED...AT LEAST INTO THE WEEKEND. EXPECT HIGHS IN THE UPPER 70S TO LOW 80S. BY MONDAY...ENERGY WILL BE REDIRECTED TOWARDS THE INCOMING UPPER LEVEL HIGH...CAUSING A BREAK IN THE UPPER LEVEL WIND FLOW ACROSS THE REGION. THIS WILL ALLOW FOR A BETTER PULL OF TRUE SW WIND FLOW IN THE MID AND LOW LEVELS...WHICH COMBINED WITH ANY SUNSHINE...WILL BOOST TEMPS BACK UP INTO THE MID AND MAYBE EVEN UPPER 80S FOR THE DAY. WITH PARTLY TO MOSTLY CLOUDY SKIES EXPECTED TO STICK AROUND DURING THE NIGHT...EXPECT TEMPERATURES TO REMAIN MODERATED AS WELL...STAYING AROUND THE MID AND UPPER 60S FOR EARLY MORNING LOWS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 215 AM EDT MON JUN 29 2015 IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE FORECAST PERIOD. AN AREA OF SCATTERED SHOWERS ASSOCIATED WITH AN APPROACHING COLD FRONTAL SYSTEM WILL OVERSPREAD THE REGION FROM WEST TO EAST AROUND DAWN THIS MORNING. SCATTERED THUNDERSTORMS ARE THEN EXPECTED TO REDEVELOP DURING THE AFTERNOON. THE PRECIPITATION MAY BRING TEMPORARY LOCALIZED IFR CONDITIONS...ESPECIALLY IN AFTERNOON THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY CONTAIN MARGINALLY LARGE HAIL AND STRONG WINDS. OTHERWISE...LIGHT SOUTHERLY WINDS WILL GRADUALLY VEER TO THE SOUTHWEST AND INCREASE TO AROUND 10 KTS...WITH HIGHER GUSTS TO AROUND 20 KTS IN THE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...RAY LONG TERM...JMW AVIATION...HAL/RAY
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1142 PM CDT SUN JUN 28 2015 .AVIATION... NO REAL CHANGE TO PREVIOUS THINKING CONCERNING THE 06Z TAF PACKAGE. SOME THIN CIRRUS MAINLY SOUTH OF THE I-20 TERMINAL LOCATIONS LATE THIS EVENING. OF ONE INTERESTING THING TO NOTE...BOTH THE 00Z WRF OUTPUT AND THE HRRR WANTS TO GENERATE SOME SHRA/TSRA ACROSS CENTRAL LA OVERNIGHT IN THE VICINITY OF A STALLED FRONTAL BOUNDARY. STARTING TO SEE SOME VERY SMALL ECHOES ON RADAR IN THIS GENERAL VICINITY ATTM BUT IF ANY DEVELOPMENT OCCURS...IT SHOULD REMAIN SOUTH AND EAST OF OUR TERMINAL LOCATIONS. CANNOT RULE OUT SOME PATCHY VERY BRIEF MVFR CEILINGS IN THE MORNING ACROSS MAINLY THE NE TX TERMINALS WHERE MOISTURE RETURN WILL BE A LITTLE STRONGER. OTHERWISE SHOULD SEE DESCENT CU FIELD DEVELOPMENT ON MONDAY AS THE RETURNING BOUNDARY TO OUR SOUTH LIFTS NORTHWARD. SHOULD SEE SOME ISOLATED TO WIDELY SCATTERED CONVECTION DURING THE AFTERNOON HOURS ON MONDAY BUT DID NOT MAKE MENTION OF THIS IN THE 06Z TAF PACKAGE. WILL BE WATCHING UP NORTH ACROSS AR/OK MONDAY EVENING/NIGHT AS AN UPPER LEVEL DISTURBANCE IN NW FLOW COULD HELP TO GENERATE SOME WIDELY SCATTERED SHOWERS AND THUNDERSTORMS. WINDS ARE LIGHT ATTM BUT WILL PICK UP AFTER SUNRISE FROM THE SSW MAINLY NEAR OR LESS THAN 10KTS. 13 && .PREV DISCUSSION... /ISSUED 933 PM CDT SUN JUN 28 2015/ DISCUSSION... OTHER THAN SOME CIRRUS ACROSS THE SOUTHERN ZONES...CLEAR SKIES AND LIGHT WIND AREA WIDE. FORECAST SEEMS TO BE ON TRACK SO NO CHANGES THIS EVENING. /14/ && .PRELIMINARY POINT TEMPS/POPS... SHV 72 94 74 91 / 0 20 30 40 MLU 70 92 74 90 / 0 20 20 50 DEQ 66 90 70 91 / 0 20 30 30 TXK 69 92 73 92 / 0 20 30 40 ELD 68 92 74 91 / 0 20 30 40 TYR 71 92 73 90 / 0 20 20 30 GGG 72 92 73 91 / 0 20 20 30 LFK 75 93 75 90 / 10 30 20 40 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 14/13
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
333 AM CDT MON JUN 29 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 332 AM CDT MON JUN 29 2015 TODAY AND TONIGHT...WINDS AT 850 MB TO 750 MB ARE SOUTH ACROSS THE CNTL HIGH PLAINS THIS MORNING AND A DISTURBANCE IS DROPPING SOUTH VERY QUICKLY IN THE NORTHWEST FLOW. STORMS ARE UNDERWAY FROM SPEARFISH SD TO CHEYENNE WY AND THE HRRR...RAP...ARW...NMM AND NAM CARRY THIS ACTIVITY INTO THE PANHANDLE AND SWRN NEB FOR A FEW HOURS THIS MORNING. SATELLITE TIMING TOOLS INDICATE THE DISTURBANCE NORTH OF THE BLACK HILLS WOULD CLEAR SWRN NEB 13Z-14Z THIS MORNING. THE ARW AND NMM MODELS SUGGEST A SMALL DISTURBANCE ON SATELLITE ACROSS SERN SASKATCHEWAN THIS MORNING COULD SPAWN ISOLATED SHOWERS AND TSTMS THIS AFTN ACROSS NCNTL NEB. THIS FEATURE IS UNDER REVIEW GIVEN THE LIMITED RADAR COVERAGE ACROSS ND AND THE LACK OF LOW LEVEL CONVERGENCE SHOWN THE MODEL CONSENSUS. THE NAM SHOWS SOUTH WINDS DEVELOPING TONIGHT BELOW 750 MB ACROSS SWRN NEB AND THIS COULD PROVIDE AN OPPORTUNITY FOR MORE CONVECTIVE DEVELOPMENT. IN FACT...SOUTH WINDS SHOULD CONTINUE TODAY ACROSS THE CNTL HIGH PLAINS ALONG HWY 385 AIMED AT THE BLACK HILLS WHICH COULD CAUSE STORMS TO FIRE ON THE BLACK HILLS THIS AFTN. THE MODEL PREDICTABILITY OF THE ONGOING CONVECTION WOULD APPEAR LOW GIVEN THAT THE RAP AND NAM SHOW NO ELEVATED INSTABILITY ACROSS THE PANHANDLE. THUS FORECAST RAIN CHANCES THIS AFTN AND TONIGHT ARE UNCERTAIN. OTHERWISE...MIXING HEIGHTS RISE TO 700 MB TODAY ALLOWING FOR A BUMP IN TEMPERATURES. HIGHS IN THE LOWER 90S SHOULD BE WIDESPREAD WITH NEARLY CLEAR SKIES. DEW POINTS IN THE 50S TO AROUND 60 SHOULD CONTINUE TODAY AND TONIGHT ALLOWING FOR ONE MORE RADIATION NIGHT WITH LOWS IN THE UPPER 50S TO LOWER 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON JUN 29 2015 SYNOPTIC PATTERN REMAINS HIGHLY AMPLIFIED THROUGH THE MIDDLE OF THE WEEK WITH ANTICYCLONIC FLOW CENTERED OVER THE GREAT BASIN...AND A TROUGH TO THE EAST CENTERED OVER THE GREAT LAKES REGION. THIS LEAVES THE CWA IN PERSISTENT NORTHWEST FLOW ALOFT. A SERIES OF SHORTWAVE TROUGHS WILL ATTEMPT TO FLATTEN THE WESTERN CONUS RIDGE AS THEY TRAVERSE TROUGH SOUTHERN CANADA. THE FIRST SHORTWAVE APPROACHES THE CWA ON TUESDAY. LOW LEVEL SOUTHWESTERLY FLOW WILL PUSH H85 TEMPS ABOVE 30C IN SOUTHWEST NEBRASKA. LATEST GUIDANCE HAS TRENDED WARMER FOR HIGH TEMPS ON TUESDAY...WITH THE MAV NOW NEARING 100 FOR PARTS OF THE AREA. HOWEVER...MODELS CONTINUE TO SHOW A CIRRUS SHIELD SPREADING OVER THE CENTRAL PLAINS AS A SURGE OF MOISTURE AOA 500MB ROUNDS THE TOP OF THE WESTERN CONUS RIDGE. STILL TRENDED HIGHS UP A DEGREE OR TWO...BUT KEPT A CONSERVATIVE APPROACH GIVEN POTENTIAL CLOUD COVER. A WEAK COLD FRONT MOVES THROUGH TUESDAY EVENING AND NIGHT AS THE SHORTWAVE PASSES ALOFT. ISOLATED STORMS WILL BE POSSIBLE ALONG AND BEHIND FRONT TUESDAY NIGHT. SHEAR WILL BE STRONG ENOUGH TO SUPPORT A FEW STRONG STORMS...BUT MODEL BUFR SOUNDINGS SHOW THAT ANY ACTIVITY WILL BE HIGHLY ELEVATED DUE TO DRY LOW LEVELS SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. BEST CHANCES FOR STORMS WILL LIKELY REMAIN JUST EAST OF THE CWA WHERE THE LLJ WILL BE FOCUSED AND BETTER MOISTURE RESIDES. TEMPERATURES WILL BE A FEW DEGREES COOLER WEDNESDAY BUT STILL RANGE FOR THE MID 80S TO LOW 90S. ISOLATED TO SCATTERED STORM CHANCES ENTER THE FORECAST ONCE AGAIN WEDNESDAY NIGHT AND THURSDAY AS THE NEXT UPPER LEVEL SHORTWAVE APPROACHES FROM THE NORTHWEST. MODELS REMAIN IN FAIR AGREEMENT THROUGH THE END OF THE WEEK AS A RIDGE ALOFT BUILDS OVER THE CENTRAL CONUS TO END THE WEEK WITH DRY CONDITIONS EXPECTED. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1109 PM CDT SUN JUN 28 2015 NO WEATHER-RELATED FLIGHT RESTRICTIONS ARE FORECAST IN CENTRAL AND WESTERN NEBRASKA THROUGH MONDAY EVENING. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MARTIN AVIATION...SPRINGER
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
422 AM EDT MON JUN 29 2015 .SYNOPSIS... RAIN SHOWERS WILL CONTINUE OVERNIGHT INTO TOMORROW MORNING AS A MID-LEVEL LOW PUSHES ACROSS THE NORTH COUNTRY. DRIER CONDITIONS BRIEFLY RETURN FOR THE LATTER HALF OF MONDAY THROUGH EARLY TUESDAY MORNING, FOLLOWED BY ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS TUESDAY AND WEDNESDAY. THE WORK WEEK WILL START WITH BELOW NORMAL TEMPERATURES AND TREND TO SLIGHTLY BELOW TO NEAR NORMAL BY MID WEEK. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... AS OF 1025 PM EDT SUNDAY...UPDATE TO DROP FLOOD WATCH AS WIDESPREAD RAIN HAS EXITED THE REGION AND RIVERS AND STREAMS ONLY RESPONDED SLIGHTLY. MOST ARE CRESTING NOW AND FALLING SO EVEN WITH ANY ADDITIONAL LIGHT RAIN THROUGH THE NIGHT WE SHOULDN`T HAVE ANY ISSUES. CURRENT RADAR CONTINUES TO SHOW SOME LIGHT RETURNS LIKELY IN THE FORM OF DRIZZLE OR LIGHT RAIN. LATEST 3KM HRRR DOES SHOW SOME ADDITIONAL SHOWER DEVELOPMENT ACROSS NORTHERN NEW YORK OVER THE NEXT FEW HOURS THOUGH AS THE UPPER LOW PUSHES THROUGH THE ST LAWRENCE VALLEY SO HAVE KEPT IN SOME LIKELY POPS THERE, BUT LOWERED EVERYWHERE ELSE AS PRECIP WILL BE MORE SCATTERED IN NATURE. OVERNIGHT LOWS WILL RANGE IN THE 50S. && .SHORT TERM /8 AM THIS MORNING THROUGH WEDNESDAY/... AS OF 325 PM EDT SUNDAY...CYCLONIC FLOW CONTINUE TO PRODUCE SOME LINGERING SHOWERS MONDAY MORNING. THE AFTERNOON WILL SEE SURFACE RIDGING AS THE 500MB LOW EXITS EAST AND ANTICYCLONIC FLOW FILTERS INTO THE NORTH COUNTRY. THIS WILL RESULT IN A DRYING TREND MONDAY AFTERNOON INTO MONDAY NIGHT. SOME AREAS COULD SEE SOME SUN BREAKING THROUGH LATE IN THE DAY. MAX TEMPERATURES WILL GENERALLY BE IN THE 60S. SOME INCREASING CLOUDS AHEAD OF THE NEXT SYSTEM MAY LIMIT SOME FOG DEVELOPMENT MONDAY NIGHT, BUT DIMINISHING WINDS WILL AID FOG DEVELOPMENT IN AT LEAST THE CLIMATOLOGICALLY FAVORABLE AREAS. MIN TEMPERATURES WILL BE IN THE 40S TO MID 50S. TUESDAY WILL SEE AN INCREASE IN INSTABILITY WITH CAPE VALUES GREATER THAN 500 J/KG AFFECTING SOUTHWEST PORTIONS OF THE AREA AS A 500MB TROUGH MOVES EASTWARD ACROSS THE CENTRAL GREAT LAKES REGION. THE ASSOCIATED SURFACE LOW WILL BRING A WARM FRONT, RAIN SHOWERS AND POSSIBLY A THUNDERSTORM ACROSS THE REGION DURING THE DAY. 850MB TEMPERATURES WILL REACH THE MID TEENS, RESULTING IN MORE SEASONABLE MAX TEMPERATURES. SHOWERS AND THUNDERSTORMS CONTINUE INTO TUESDAY NIGHT AS THE SURFACE LOW MOVES NORTHEASTWARD INTO SOUTHERN QUEBEC WITH UPPER LEVEL JET ENHANCING LIFT AND PROLONGING THREAT FOR THUNDERSTORMS. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 419 AM EDT MONDAY...MAINTENANCE OF INTERMOUNTAIN WEST MID- TROPOSPHERIC RIDGE WILL RESULT IN CONTINUATION OF SEASONABLE TEMPERATURES AND EPISODES OF SHOWER ACTIVITY ACROSS THE NORTH COUNTRY IN ASSOCIATION WITH MEAN TROUGH ACROSS THE AREA DURING THE EXTENDED FORECAST PERIOD. EXPECTATION IS FOR MID-LEVEL SHORTWAVE TROUGH TO BE EXITING THE AREA EARLY WEDNESDAY NIGHT WITH DIMINISHING CHANCES FOR SHOWERS (AND SLIGHT CHANCE OF TSTMS) DURING THE EARLY EVENING HOURS. SHOULD SEE A DRIER NW FLOW PATTERN SET UP BRIEFLY PROVIDING FOR A GENERALLY DRY CONDITIONS THURSDAY AND FRIDAY...WITH VALLEY HIGH TEMPERATURES BOTH DAYS IN THE MID TO UPPER 70S. NEXT SHORTWAVE TROUGH POTENTIALLY SHIFTS EWD FROM THE GREAT LAKES REGION INTO THE NORTH COUNTRY FOR INDEPENDENCE DAY (SATURDAY) PER 00Z ECMWF. HOWEVER...IT IS WORTH NOTING THAT THE 00Z GFS IS SLOWER AND WEAKER WITH THIS PARTICULAR FEATURE AND SUGGESTS GENERALLY DRY CONDITIONS WILL PERSIST THRU THE DAY SATURDAY. HAVE INCLUDED 30-40 POPS FOR SHOWERS AND POSSIBLE TSTMS SATURDAY AFTN AT THIS POINT...AS 00Z ECMWF HAS BETTER CONTINUITY WITH PREVIOUS ECMWF AND GFS RUNS. TEMPERATURES SHOULD REMAIN IN THE MID-UPR 70S FOR AFTERNOON HIGHS FOR THE 4TH OF JULY...AND GENERALLY LOW 60S FOR LOWS SATURDAY NIGHT. LOWER PRECIPITATION CHANCES FOR SUNDAY.&& .AVIATION /08Z MONDAY THROUGH FRIDAY/... THROUGH 12Z TUESDAY...AREAS OF DRIZZLE/MIST WILL PREVAIL AT THE NORTH COUNTRY TAF LOCATIONS THROUGH ABOUT 12Z THIS MORNING AS UPPER LOW TRANSLATES NEWD ACROSS THE REGION. IT APPEARS IFR CONDITIONS WILL PREVAIL AT MSS/SLK...WITH MAINLY MVFR-VFR CONDITIONS ELSEWHERE. CAN/T RULE OUT A FEW RAIN SHOWERS AS WELL...THOUGH THEY SHOULD BE BRIEF IN DURATION BASED ON 0530Z RADAR TRENDS. CONDITIONS TREND VFR DURING THE DAYLIGHT HOURS WITH LIGHT (5-8KT) W TO NW WINDS. CLEARING SKIES OVERNIGHT WILL LEAD TO PATCHY DENSE FOG FORMATION AFTER 05-06Z...WITH LIFR ANTICIPATED AT MPV/SLK/MSS AND POSSIBLE AT THE REMAINING TAF LOCATIONS GIVEN LIGHT AND VARIABLE WINDS AND SATURATED GROUND CONDITIONS. OUTLOOK 12Z TUESDAY THROUGH FRIDAY...UPPER LEVEL DISTURBANCE BRINGS SCATTERED RAIN SHOWERS LATE TUESDAY INTO TUESDAY NIGHT...WITH REDEVELOPMENT OF SHOWERS AND POSSIBLE TSTMS DURING THE DAY WEDNESDAY. INTERVALS OF IFR/MVFR CONDITIONS POSSIBLE WITH CONVECTIVE ACTIVITY. TRENDING DRIER BY LATE WEDNESDAY EVENING RIGHT THROUGH FRIDAY...BUT COULD SEE NOCTURNAL FOG DEVELOPMENT EARLY THURSDAY AM AND AGAIN EARLY FRIDAY AM...ESPECIALLY MPV/SLK. && .CLIMATE... AS OF 400 AM EDT MONDAY...IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. ONE MONTHLY RECORD HAS ALREADY BEEN SET AT MONTPELIER, AND THE POTENTIAL FOR MORE RAIN LATE TUESDAY, THE RECORDS AT BURLINGTON AND MOUNT MANSFIELD WILL BE APPROACHED. MONTPELIER HAS BROKEN ITS MONTHLY JUNE RAINFALL RECORD. AS OF 5 PM, 8.92 INCHES OF RAINFALL HAD FALLEN IN JUNE 2015 AT MONTPELIER. THE PRIOR RECORD WAS 8.36 INCHES SET IN 2013. A SUMMARY OF CURRENT RAINFALL TOTALS FOR BURLINGTON AND MT. MANSFIELD, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS AS OF MIDNIGHT 06/29. AT 8.62 INCHES, BURLINGTON NEEDS 1.30 INCHES OF ADDITIONAL RAINFALL TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET BACK IN 1922. AT 14.87 INCHES, MT. MANSFIELD NEEDS 0.41 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...KGM NEAR TERM...LAHIFF SHORT TERM...KGM LONG TERM...BANACOS AVIATION...BANACOS CLIMATE...TEAM BTV
AREA FORECAST DISCUSSION
NWS BURLINGTON VT
157 AM EDT MON JUN 29 2015 .SYNOPSIS... RAIN SHOWERS WILL CONTINUE OVERNIGHT INTO TOMORROW MORNING AS A MID-LEVEL LOW PUSHES ACROSS THE NORTH COUNTRY. DRIER CONDITIONS BRIEFLY RETURN FOR THE LATTER HALF OF MONDAY THROUGH EARLY TUESDAY MORNING, FOLLOWED BY ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS TUESDAY AND WEDNESDAY. THE WORK WEEK WILL START WITH BELOW NORMAL TEMPERATURES AND TREND TO SLIGHTLY BELOW TO NEAR NORMAL BY MID WEEK. && .NEAR TERM /UNTIL 8 AM THIS MORNING/... AS OF 1025 PM EDT SUNDAY...UPDATE TO DROP FLOOD WATCH AS WIDESPREAD RAIN HAS EXITED THE REGION AND RIVERS AND STREAMS ONLY RESPONDED SLIGHTLY. MOST ARE CRESTING NOW AND FALLING SO EVEN WITH ANY ADDITIONAL LIGHT RAIN THROUGH THE NIGHT WE SHOULDN`T HAVE ANY ISSUES. CURRENT RADAR CONTINUES TO SHOW SOME LIGHT RETURNS LIKELY IN THE FORM OF DRIZZLE OR LIGHT RAIN. LATEST 3KM HRRR DOES SHOW SOME ADDITIONAL SHOWER DEVELOPMENT ACROSS NORTHERN NEW YORK OVER THE NEXT FEW HOURS THOUGH AS THE UPPER LOW PUSHES THROUGH THE ST LAWRENCE VALLEY SO HAVE KEPT IN SOME LIKELY POPS THERE, BUT LOWERED EVERYWHERE ELSE AS PRECIP WILL BE MORE SCATTERED IN NATURE. OVERNIGHT LOWS WILL RANGE IN THE 50S. && .SHORT TERM /8 AM THIS MORNING THROUGH TUESDAY NIGHT/... AS OF 325 PM EDT SUNDAY...CYCLONIC FLOW CONTINUE TO PRODUCE SOME LINGERING SHOWERS MONDAY MORNING. THE AFTERNOON WILL SEE SURFACE RIDGING AS THE 500MB LOW EXITS EAST AND ANTICYCLONIC FLOW FILTERS INTO THE NORTH COUNTRY. THIS WILL RESULT IN A DRYING TREND MONDAY AFTERNOON INTO MONDAY NIGHT. SOME AREAS COULD SEE SOME SUN BREAKING THROUGH LATE IN THE DAY. MAX TEMPERATURES WILL GENERALLY BE IN THE 60S. SOME INCREASING CLOUDS AHEAD OF THE NEXT SYSTEM MAY LIMIT SOME FOG DEVELOPMENT MONDAY NIGHT, BUT DIMINISHING WINDS WILL AID FOG DEVELOPMENT IN AT LEAST THE CLIMATOLOGICALLY FAVORABLE AREAS. MIN TEMPERATURES WILL BE IN THE 40S TO MID 50S. TUESDAY WILL SEE AN INCREASE IN INSTABILITY WITH CAPE VALUES GREATER THAN 500 J/KG AFFECTING SOUTHWEST PORTIONS OF THE AREA AS A 500MB TROUGH MOVES EASTWARD ACROSS THE CENTRAL GREAT LAKES REGION. THE ASSOCIATED SURFACE LOW WILL BRING A WARM FRONT, RAIN SHOWERS AND POSSIBLY A THUNDERSTORM ACROSS THE REGION DURING THE DAY. 850MB TEMPERATURES WILL REACH THE MID TEENS, RESULTING IN MORE SEASONABLE MAX TEMPERATURES. SHOWERS AND THUNDERSTORMS CONTINUE INTO TUESDAY NIGHT AS THE SURFACE LOW MOVES NORTHEASTWARD INTO SOUTHERN QUEBEC WITH UPPER LEVEL JET ENHANCING LIFT AND PROLONGING THREAT FOR THUNDERSTORMS. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 325 PM EDT SUNDAY...LONGWAVE PATTERN REMAINS WELL-SPECIFIED IN THE EXTENDED PERIOD, WITH THE NORTH COUNTRY CONTINUES IN MEAN CYCLONIC FLOW ALOFT. IT`S A GENERALLY UNSETTLED PERIOD WITH A SERIES OF EMBEDDED SHORTWAVE TROUGHS/VORT MAXES PROGGED TO IMPACT THE NORTH COUNTRY. HOWEVER, THERE IS LESS CLARITY NOTED IN 12Z NWP SUITE THAN PRIOR CYCLES REGARDING TIMING AND AMPLITUDE OF AFOREMENTIONED SHORTWAVES. I`VE OPTED TO USE A HEAVY DOSE OF BLENDED GUIDANCE FOR THIS PERIOD. DAILY DETAILS FOLLOW... WEDNESDAY: LOOKS TO BE THE MOST ACTIVE IN THE PERIOD AS A DIGGING SHORTWAVE INTO OHIO VALLEY REGION CARVES OUT MEAN SOUTHWEST FLOW ALOFT ACROSS NORTH COUNTRY. THAT ALLOWS FOR A PLUME OF RELATIVELY HIGH PWAT AIR (UP TO 1.5 INCHES) TO ADVECT NORTHEASTWARD PARALLEL TO SFC COLD FRONTAL BOUNDARY. PER 12Z GFS, WARM SECTOR AIRMASS CHARACTERIZED BY LI`S OF -4 AND CAPE VALUES AOB 1000 J/KG, WITH DEEP LAYER SHEAR VALUES 35-40 KTS. SO THERE COULD BE A WINDOW FOR STRONGER THUNDERSTORMS WITH LOCALLY HEAVY RAIN/HYDRO CONCERNS WEDNESDAY AFTN/EVENING. KEPT POPS HIGH LIKELY/LOW CATEGORICAL FOR VT AND CLOSER TO LIKELY FOR NORTHER NY. SHOWN FORECAST QPF WEDNESDAY UP TO A HALF INCH, BUT LOCALLY MORE IN CONVECTION. DEPENDING ON SPEED THAT FRONT EXITS - WHICH MAY TURN OUT TO BE SLOWER - SHOULD HAVE POST-FRONTAL CAA REGIME WEDNESDAY NIGHT. HIGHS IN THE 70S WITH LOWS IN THE M50S/NEAR 60. THURSDAY: GFS/EC REALLY ARE AT ODDS WITH REGARD TO HOW THURSDAY PLAYS OUT. THE GFS DEPICTS AN AMPLIFYING SHORTWAVE WITH LARGER QPF ON THURSDAY, WHILE THE EC SHOWS MORE SHEARED-OUT SHORTWAVE FEATURES AND LOWER QPF. KEPT IDEA OF SLIGHT CHANCE TO CHANCE POPS FOR THURSDAY. FRIDAY LOOKS TO BE THE DRIEST DAY IN THE PERIOD, BUT WILL TURN UNSETTLED HEADING INTO FRIDAY NIGHT AND INTO THE WEEKEND OF INDEPENDENCE DAY AS THE NEXT IN THE PARADE OF SHORTWAVE TROUGHS DIGS INTO THE GREAT LAKES REGION. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... THROUGH 12Z TUESDAY...AREAS OF DRIZZLE/MIST WILL PREVAIL AT THE NORTH COUNTRY TAF LOCATIONS THROUGH ABOUT 12Z THIS MORNING AS UPPER LOW TRANSLATES NEWD ACROSS THE REGION. IT APPEARS IFR CONDITIONS WILL PREVAIL AT MSS/SLK...WITH MAINLY MVFR-VFR CONDITIONS ELSEWHERE. CAN/T RULE OUT A FEW RAIN SHOWERS AS WELL...THOUGH THEY SHOULD BE BRIEF IN DURATION BASED ON 0530Z RADAR TRENDS. CONDITIONS TREND VFR DURING THE DAYLIGHT HOURS WITH LIGHT (5-8KT) W TO NW WINDS. CLEARING SKIES OVERNIGHT WILL LEAD TO PATCHY DENSE FOG FORMATION AFTER 05-06Z...WITH LIFR ANTICIPATED AT MPV/SLK/MSS AND POSSIBLE AT THE REMAINING TAF LOCATIONS GIVEN LIGHT AND VARIABLE WINDS AND SATURATED GROUND CONDITIONS. OUTLOOK 12Z TUESDAY THROUGH FRIDAY...UPPER LEVEL DISTURBANCE BRINGS SCATTERED RAIN SHOWERS LATE TUESDAY INTO TUESDAY NIGHT...WITH REDEVELOPMENT OF SHOWERS AND POSSIBLE TSTMS DURING THE DAY WEDNESDAY. INTERVALS OF IFR/MVFR CONDITIONS POSSIBLE WITH CONVECTIVE ACTIVITY. TRENDING DRIER BY LATE WEDNESDAY EVENING RIGHT THROUGH FRIDAY...BUT COULD SEE NOCTURNAL FOG DEVELOPMENT EARLY THURSDAY AM AND AGAIN EARLY FRIDAY AM...ESPECIALLY MPV/SLK. && .CLIMATE... AS OF 500 PM EDT SUNDAY...IT`S BEEN AN ANOMALOUSLY WET JUNE ACROSS THE NORTH COUNTRY. ONE MONTHLY RECORD HAS ALREADY BEEN SET AT MONTPELIER AND WITH ADDITIONAL RAINFALL TONIGHT INTO TOMORROW, AND THE POTENTIAL FOR MORE RAIN ON TUESDAY, THE RECORDS AT BURLINGTON AND MOUNT MANSFIELD ARE IN JEOPARDY. AS OF 5 PM SUNDAY AFTERNOON, MONTPELIER HAS BROKEN ITS MONTHLY JUNE RAINFALL RECORD. AS OF 5 PM, 8.85 INCHES OF RAINFALL HAD FALLEN IN JUNE 2015 AT MONTPELIER. THE PRIOR RECORD WAS 8.36 INCHES SET IN 2013. A SUMMARY OF CURRENT RAINFALL TOTALS FOR BURLINGTON AND MT. MANSFIELD, AND WHAT IT WILL TAKE TO BREAK THE JUNE RECORD FOLLOWS BELOW. NOTE THAT CITED RAINFALL VALUES REFLECT AMOUNTS AS OF 5 PM 06/28. AT 8.44 INCHES, BURLINGTON NEEDS 1.48 INCHES OF ADDITIONAL RAINFALL TO BREAK THE JUNE RAINFALL RECORD OF 9.22 INCHES SET IN 1922. AT 14.87 INCHES, MT. MANSFIELD NEEDS 0.41 INCHES OF ADDITIONAL RAIN TO BREAK THE JUNE RAINFALL RECORD OF 15.28 INCHES SET IN 1998. && .BTV WATCHES/WARNINGS/ADVISORIES... VT...NONE. NY...NONE. && $$ SYNOPSIS...KGM NEAR TERM...LAHIFF SHORT TERM...KGM LONG TERM...LOCONTO AVIATION...BANACOS CLIMATE...LOCONTO/MUCCILLI
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1209 AM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 1209 AM CDT MON JUN 29 2015 LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE OVER NORTHEAST MONTANA ACCOMPANIED BY A 70KT 300MB JET STREAK NOSING/DIVING INTO EASTERN MONTANA. ISOLATED CONVECTION FROM LAST FEW HOURS AS WANED WITH IR SATELLITE SHOWING TOPS WARMING FROM SASKATOON INTO REGINA. THE 00Z HIGH RESOLUTION ARW AND NMM IS NOW VOID OF ANY PRECIPITATION OVERNIGHT. THE LATEST HRRR IS OVERDONE. HAVE REMOVED THE SLIGHT CHANCE MENTION OF THUNDERSORMS WEST OVERNIGHT. IF SOMETHING REMOTELY DOES DEVELOP...FEEL THE COVERAGE AFFECTED WOULD NOT JUSTIFY THE EXTENSIVE AREA OF SLIGHT CHC IN THE GRIDS AT THIS TIME. THE OTHER UPDATE WAS TO ADD HAZE IN THE GRIDS CENTRAL ZONES...WITH SHALLOW INVERSIONS SETTING UP OVERNIGHT. JAMESTOWN AIRPORT VISIBILITY HAS FALLEN TO 6SM AND BISMARCK HAS BEEN FLUCTUATING BETWEEN 7SM AND 8SM. WITH STREAM OF SMOKE CONTINUING TO TRAVEL FROM CENTRAL CANADA INTO CENTRAL NORTH DAKOTA...EXPECT HAZE AND SKY OBSCURATION WILL CONTINUE THROUGH AT LEAST MONDAY MORNING. UPDATE ISSUED AT 938 PM CDT SUN JUN 28 2015 CANT COMPLETELY RULE OUT AN ISOLATED THUNDERSTORM TONIGHT BUT CHANCES ARE LOOKING SLIMMER. THERE IS STILL SOME CONVECTION IN SASKATCHEWAN BUT WOULD TAKE A WHILE FOR IT TO REACH NORTH DAKOTA. NO SIGNIFICANT CHANGES TO THE GOING FORECAST. UPDATE ISSUED AT 620 PM CDT SUN JUN 28 2015 LATEST SATELLITE IMAGERY INDICATES A WEAK SHORTWAVE OVER SOUTH CENTRAL SASKATCHEWAN/NORTHEAST MONTANA RIDING ALONG A 70KT JETSTREAK THAT WILL DROP SOUTHEAST ACROSS EASTERN MONTANA/FAR WESTERN NORTH DAKOTA TONIGHT. CURRENTLY THERE IS SOME CONVECTION ALONG THE INTERNATIONAL BORDER NORTH OF GLASGOW. ADDITIONAL CONVECTION HAS DEVELOPED OVER SOUTHEAST MONTANA BUT WITH A SOUTHEAST MOVEMENT SHOULD STAY TO THE WEST OF SOUTHWEST NORTH DAKOTA. STILL CAN NOT RULE OUT AN ISOLATED THUNDERSTORM TONIGHT ACROSS THE WEST AND WILL LEAVE THE SLIGHT CHANCE POPS FOR NOW. OTHERWISE...MOSTLY CLEAR ACROSS THE FORECAST AREA...BUT A BAND OF SMOKE FROM CANADIAN FIRES IS CURRENTLY DRAPED ACROSS CENTRAL NORTH DAKOTA AND MOVING SLOWLY TO THE SOUTHEAST ALONG THE PERIPHERY OF THE UPPER LEVEL RIDGE. && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 250 PM CDT SUN JUN 28 2015 RELATIVELY BENIGN WEATHER PATTERN IN PLACE WITH WARM WEATHER THROUGH MONDAY...LIGHT WINDS AND MOSTLY DRY CONDITIONS. HAZY SKIES TODAY ARE DUE TO SMOKE FROM CANADIAN WILDFIRES STREAMING OVER THE NORTHERN PLAINS IN NORTHWEST FLOW ALOFT AS LONGWAVE RIDGE WAS POSITIONED OVER THE INTERMOUNTAIN WEST. SMOKE MAY CONTINUE TO AFFECT OUR REGION WITH NORTHWEST FLOW ALOFT REMAINING THROUGH MONDAY. MODELS ALSO CONTINUE TO DEPICT A WEAK SHORTWAVE RIDING DOWN BACKSIDE OF UPPER RIDGE TONIGHT BRUSHING WESTERN NORTH DAKOTA. MOST OF THE MODELS ARE DRY...WITH GFS BEING A LITTLE MORE AGGRESSIVE GENERATING SOME LIGHT PRECIPITATION FROM SOME ELEVATED CONVECTION. THE INHERITED FORECAST CARRIED SLIGHT CHANCE POPS ACROSS THE WEST AND THIS STILL LOOKS REASONABLE. ON MONDAY HIGH PRESSURE REMAINS IN PLACE OVER THE NORTHERN PLAINS WITH ANOTHER WARM DAY WITH HIGHS IN THE MID/UPPER 80S. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 250 PM CDT SUN JUN 28 2015 COOLER WITH INCREASING CHANCES FOR THUNDERSTORMS TUESDAY THROUGH THURSDAY. UPPER LEVEL RIDGING ACROSS THE WESTERN CONUS IS FORECAST TO BEGIN TO BREAK DOWN BY TUESDAY. THIS WOULD PUT THE NORTHERN PLAINS IN NORTHWEST FLOW...ALLOWING MANY FAST MOVING SHORT WAVE TROUGHS TO SWING THROUGH. ONCE SUCH WAVE IS BEING PICKED UP BY THE MODELS TO MOVE THROUGH TUESDAY/WEDNESDAY AND ANOTHER WEDNESDAY/THURSDAY. THUNDERSTORMS ARE POSSIBLE EACH DAY AS SOUTH WINDS USHER IN ADDITIONAL MOISTURE AND LEE SURFACE LOWS DEVELOP AHEAD OF THE UPPER LEVEL SHORT WAVES. BASICALLY WE ARE SEEING A RETURN TO THE PATTERN WE HAD EARLY LAST WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1209 AM CDT MON JUN 29 2015 SMOKE FROM CENTRAL CANADIAN WILDFIRES CONTINUES TO TRAVEL INTO NORTH DAKOTA. DEPTH OF HAZE PARTICULATES WILL INCREASE AND LOWER REST OF TONIGHT INTO MONDAY MORNING AS SHALLOW INVERSIONS BECOME ESTABLISHED. PERIODS OF MVFR VSBYS POSSIBLE OVERNIGHT INTO MONDAY MORNING...BUT FOR NOW WILL KEEP VSBYS AT OR ABOVE 6SM. OTHERWISE VFR CIGS AND VSBYS CONTINUE THIS TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...JNS LONG TERM...AJ AVIATION...KS
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
152 AM EDT MON JUN 29 2015 .SYNOPSIS... LOW PRESSURE WILL CONTINUE TO MOVE EASTWARD ACROSS NEW YORK TONIGHT. ANOTHER AREA OF LOW PRESSURE WILL MOVE ACROSS THE REGION ON MONDAY WITH A COLD FRONT STALLING ACROSS CENTRAL OHIO. THIS BOUNDARY WILL BECOME A FOCUS ON TUESDAY AS UPPER LEVEL JET ENERGY PASSES OVERHEAD. THE STALLED FRONTAL BOUNDARY MAY THEN PRODUCE ADDITIONAL SHOWERS AND THUNDERSTORMS ON WEDNESDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... BACK EDGE OF STRATOCU HAS NOW MADE ITS WAY INTO NW PA. LAST FEW SHRA APPEAR TO JUST BE IN EASTERN ERIE CO PA. WILL CONTINUE TO RAMP DOWN POPS AND CLOUDS IN NW PA THRU MIDNIGHT BUT WILL KEEP LINGERING SLIGHT CHC FOR THE SNOWBELT LATER TONIGHT AS HRRR AND RAP INDICATE SOME LIGHT SHRA DEVELOPING SE INTO THE AREA. HIGHER CLOUDS FROM TOMORROW`S SYSTEM WILL CONTINUE TO SPREAD INTO THE WEST. CURRENT SHRA OVER INDIANA SHOULD DISSIPATE BEFORE REACHING THE WEST BUT ANOTHER PUSH IS EXPECTED LATE IN THE NIGHT. A FEW SHRA COULD REACH THE EXTREME WESTERN FRINGE AROUND DAYBREAK SO WILL KEEP A SMALL CHC POP THERE FOR THE LAST HOUR OF THE NIGHT. MOST OF THE CWA SHOULD DIP INTO THE 50S WITH THE LOWEST TEMPERATURES OVER THE INLAND PART OF THE EASTERN SNOWBELT WHERE LOWER 50S SHOULD BE COMMON. THE INCREASING CLOUDS AND DEVELOPING SOUTH WINDS IN THE WEST WILL PROBABLY HOLD LOWS IN A 58 TO 60 RANGE. && .SHORT TERM /6 AM THIS MORNING THROUGH WEDNESDAY NIGHT/... THE NEXT AREA OF LOW PRESSURE WILL MOVE ACROSS THE AREA ON MONDAY BUT THERE IS SOME UNCERTAINTY ON ITS EXACT TRACK. AT THIS POINT IT APPEARS THE CONVECTION THAT DEVELOPS OVER MISSOURI AND ILLINOIS WILL MOVE TOWARD THE REGION OVERNIGHT. THIS CONVECTION WILL ATTEMPT TO MOVE INTO NW OHIO NEAR OR SHORTLY AFTER SUNRISE. THIS CONVECTION SHOULD BE WEAKENING AS IS MOVES INTO THAT AREA. WE DID CONSIDER A FLOOD WATCH FOR NEW FLOODING BUT SINCE WE THINK THE QPF SHOULD BE UNDER HALF AN INCH WE HELD OFF FOR NOW. IF THIS CONVECTION CHARGES TOWARD THE AREA STRONGER THAN ANTICIPATED THEN THE FLOOD THREAT WILL HAVE TO BE REEVALUATED. AS THIS AREA OF LOW PRESSURE PASSES MONDAY EVENING IT WILL PUSH A WEAKENING COLD FRONT ACROSS THE AREA. THE BOUNDARY WILL STALL NEAR CENTRAL OHIO BUT EVEN THAT IS UNCERTAIN AT THIS POINT. THIS BOUNDARY AND A COUPLE PIECES OF JET ENERGY WILL THEN BE THE MAIN PLAYERS FR THE FORECAST ON TUESDAY AND WEDNESDAY. THE BEST CHANCES OF RAIN LOOK TO BE ACROSS THE SOUTHERN COUNTY WARNING AREA TUESDAY AFTERNOON. HIGH PRESSURE MAY BEGIN TO MOVE INTO THE AREA WEDNESDAY NIGHT FROM SOUTHERN CANADA. THE HIGH TEMPERATURE FORECASTS WILL CONTINUE TO BE SLIGHTLY BELOW SEASONAL AVERAGES BUT COULD VARY SLIGHTLY DEPENDING ON THE AMOUNT OF CONVECTIVE DEBRIS CLOUDINESS EACH DAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... WISH THE HOLIDAY FORECAST WAS CUT AND DRY...BUT WITH THE EASTERN U.S. MAINTAINING A BROAD TROUGH...WILL STILL HAVE TO DEAL WITH UNSETTLED WEATHER. HAVE SIDED TOWARD AN ENSEMBLE SOLUTION TO TRY AND PINPOINT THE BETTER CHANCES OF PRECIPITATION. THEREFORE FOR NOW HAVE THE BEST CHANCES OF SHOWERS/THUNDERSTORMS BETWEEN FRIDAY AND FRIDAY NIGHT AS LOW PRESSURE MAY BE WORKING ACROSS THE LOWER GREAT LAKES. UNSURE WHETHER THE FRONT CLEARS HERE SO LINGERED SOME PRECIP CHANCES INTO SATURDAY. BY SUNDAY THROUGH ENS MEAN HAS A RIDGE BEGINNING TO MOVE ACROSS THE OHIO VALLEY. TEMPERATURES THROUGH THE PERIOD WILL BE SEASONABLE. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... NEXT STORM SYSTEM FAST APPROACHING FROM THE WEST. EXPECTING RAIN TO MOVE INTO THE AREA FROM WEST TO EAST AND SHOULD ARRIVE IN TOLEDO AND FINDLAY LATER THIS MORNING. ERIE MAY WIN OUT TODAY AND STAY DRY FOR MUCH OF THE DAY AND THEN RAIN WILL SPREAD INTO THAT AREA THIS EVENING. EXPECTING CEILINGS AND VISIBILITY TO FALL THIS AFTERNOON AND EVENING AS WELL AS RAIN MOVES INTO THE AREA. IFR TO MVFR CONDITIONS EXPECTED OVERNIGHT. WINDS ARE NOT EXPECTED TO BE MORE MORE THAN 10 TO 15 KNOTS THROUGH THE PERIOD. OUTLOOK...NON VFR POSSIBLY LINGERING INTO TUESDAY. AREAS OF NON VFR WEDNESDAY. && .MARINE... HAVE HAD TO EXTEND THE SMALL CRAFT ADVISORY INTO THE EVENING FOR EAST OF THE ISLANDS. BUOY OFF OF CLEVELAND AND REPORTS OFF OF ERIE PA STILL INDICATE 4 TO 5 FOOTERS. HIGH PRESSURE WILL ACROSS THE LAKE TONIGHT SO WIND/WAVES WILL SETTLE. NEXT SYSTEMS TRACK OF THE LOW FOR MONDAY INTO TUESDAY WILL BE CRITICAL TO THE EXACT DIRECTION AND SPEED OF THE WIND ON THE LAKE. HAVE TAKEN THE LOW ACROSS THE WESTERN BASIN AND INTO ONTARIO MONDAY NIGHT PRODUCING A STIFF ESE FLOW FOR THE WESTERN HALF OF THE LAKE MONDAY FOLLOWED BY SOUTHWEST WINDS TUESDAY. THERE ARE SOME SOLUTIONS THAT TAKE IT MORE ACROSS THE CENTER OF THE LAKE AND THEREFORE WOULD YIELD DIFFERENT WIND/WAVES ON THE LAKE. GRADIENT BECOMES MUCH WEAKER FOR MID WEEK AND WINDS WILL BE OF NO ISSUE. HIGH PRESSURE DOES NOT CLEANLY MAKE IT TO THE LAKE UNTIL MAYBE THURSDAY. ANOTHER SYSTEM LOOKS TO BE HEADED OUR WAY FOR FRIDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...MULLEN NEAR TERM...ADAMS/MULLEN SHORT TERM...MULLEN LONG TERM...OUDEMAN AVIATION...LOMBARDY MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS PORTLAND OR
923 PM PDT SUN JUN 28 2015 .SYNOPSIS...SCATTERED SHOWERS AND THUNDERSTORMS ARE POSSIBLE MONDAY AS A WEAK DISTURBANCE OFF THE NORTHERN CALIFORNIA COAST LIFTS NORTHWARD. FLOW ALOFT TURNS MORE WESTERLY THE NEXT COUPLE DAYS DECREASING THE HUMIDITY IN THE AIR MASS...BUT TEMPERATURES SHOULD REMAIN WELL ABOVE NORMAL THROUGH THE WEEK. VERY STRONG UPPER LEVEL RIDGING WILL LIKELY REDEVELOP ACROSS THE PACIFIC NORTHWEST LATER THIS WEEK...WITH ANOTHER ROUND OF VERY HOT AND DRY WEATHER FOR THE LATTER PART OF THE WEEK INTO THE HOLIDAY WEEKEND. && .UPDATE...CONVECTION APPEARS TO BE DONE FOR THE DAY WITH THE LAST OF THE RADAR ECHOES MOVING OUT OF THE LOCAL AREA. HAVE CLEARED RAIN AND LIGHTNING CHANCES OUT OF THE FORECAST THROUGH 06Z. THE NEXT FEATURE TO WATCH IS THE UPPER LOW CURRENTLY OFF THE COAST OF NORTHERN CALIFORNIA. THIS LOW WILL MOVE NORTH AND EAST INTO OREGON OVERNIGHT AS IT WEAKENS AND WILL PROVIDE SOME ADDITIONAL FORCING. AT THIS POINT IT LOOKS LIKE ANY PRECIP CHANCES WILL BE LIMITED TO THE COAST AND CASCADES WITH A SLIGHT CHANCE OF THUNDER IN THE CASCADES AS WELL. BASED ON THE LATEST MODEL TRENDS...IT SEEMS LIKE RAIN AND LIGHTNING CHANCES FOR THE VALLEY ARE NEGLIGIBLE AT BEST AND SO HAVE KEPT POPS AND WX OUT OF THE FORECAST THERE OVERNIGHT. THERE REMAINS A SLIGHT CHANCE THAT THE NORTHERN VALLEY IN PARTICULAR COULD SEE A BIT OF RAIN MONDAY MORNING BUT THE NAM...WHICH SEEMS TO BE DOING THE BEST JOB WITH THE CURRENT SITUATION...IS TRENDING DRYER FOR MONDAY. NEVERTHELESS...WILL LEAVE A SLIGHT CHANCE SHOWERS IN THE FORECAST FOR MONDAY MORNING AND SLIGHT CHANCE LIGHTNING AND SHOWERS FOR THE CASCADES. THE OTHER QUESTION TONIGHT IS LOW TEMPERATURES. LAST NIGHT AT 9PM PDX HAD JUST FALLEN BELOW 90 DEGREES WHEREAS TONIGHT THE TEMPERATURE IS 74 DEGREES. WITH DEWPOINTS AROUND 60...THE POSSIBILITY EXISTS THAT TEMPERATURES COULD DROP SIGNIFICANTLY LOWER THAT THIS MORNING`S 70 DEGREES. HOWEVER MODELS ARE DEVELOPING STRATUS ALONG THE WESTERN EDGE OF THE CASCADES WHICH WILL LOOK TO BACKBUILD OVER THE VALLEY THROUGH THE OVERNIGHT HOURS. IF THIS STRATUS DOES DEVELOP...IT WILL KEEP TEMPERATURES WARMER AND THE CURRENT FORECAST LOW AT PDX OF 67 WILL BE REASONABLE. HOWEVER IF THE TEMPERATURE FALLS SIGNIFICANTLY BEFORE THE STRATUS FORMS OR IF THE STRATUS DOES NOT OCCUR...LOW TEMPERATURES IN THE PORTLAND METRO WILL MORE LIKELY FALL INTO THE LOW 60S. MODELS SEEMS FAIRLY INSISTENT RIGHT NOW ABOUT THE STRATUS FORMATION BUT THE CURRENTLY PRESENT CUMULUS WILL LIKELY HAVE TO CLEAR OUT FIRST BEFORE ANY STRATUS CAN FORM. WITH THE UNCERTAINTY...WILL NOT LOWER OVERNIGHT TEMPERATURES IN THE NORTH VALLEY. TEMPERATURES FURTHER SOUTH APPEAR REASONABLE AT THIS POINT WITH LOW 60S IN THE SALEM AREA AND AROUND 60 FOR THE EUGENE AREA. WILL LIKELY BREAK MORE WARM LOW RECORDS MONDAY AS CURRENT RECORDS IN THE VALLEY RANGE FROM 60 IN EUGENE TO 68 IN PORTLAND BUT ONLY 64 IN VANCOUVER. HOWEVER...BECAUSE THIS EVENING IS SIGNIFICANTLY COOLER THAN LAST EVENING...SLEEPING CONDITIONS SHOULD BE A BIT BETTER TONIGHT INLAND. BOWEN .SHORT TERM (PREVIOUS DISCUSSION)...TONIGHT THROUGH WEDNESDAY...PLENTY OF CLOUDS ARE STREAMING NORTHWESTWARD ACROSS OREGON AND WESTERN WASHINGTON TODAY...BUT THEY HAVE ONLY PRODUCED A FEW LIGHTNING STRIKES SINCE LATE MORNING. UPPER LEVEL LOW PRESSURE OFF THE NORTHERN CALIFORNIA COAST IS OPENING UP AND WILL GRADUALLY LIFT N-NE THROUGH MONDAY. A FAIRLY STEADY STREAM OF MOISTURE IS LIFTING NORTHWARD AHEAD OF THIS SYSTEM...PUSHING PRECIPITABLE WATER UP TOWARD 1.50 INCH ACROSS MUCH OF THE FORECAST AREA. FORECAST SOUNDINGS ARE MOIST AND MARGINALLY UNSTABLE ALOFT...SEEMING TO NEED SOME SORT OF ATMOSPHERIC TRIGGER TO SET OFF MORE WIDESPREAD LIGHTNING...SOMETHING THAT HAS BEEN ABSENT SINCE THE LAST WEAK SHORTWAVE LIFTED INTO WRN WA EARLIER TODAY. CLOUD COVER HAS ALSO MITIGATED SFC-BASED CONVECTION THUS FAR. EXPECT TO SEE AN UPTICK IN LIGHTNING LATER THIS AFTERNOON AS THE STRONG JUNE SUN CONTINUES TO HEAT THE SURFACE DESPITE THE CLOUD COVER. TEMPERATURES IN THE CASCADES ARE NEARING THEIR CONVECTIVE TEMPS BASED ON MODEL SOUNDINGS...SO EXPECT TO SEE A FEW SFC-BASED STORMS FIRE SOON. AN UPPER LEVEL TRIGGER WILL ALSO COME IN THE FORM OF A 70-90 KT SOUTHERLY JET PUSHES INTO WRN OREGON FROM NORTHERN CALIFORNIA. THE LAST SEVERAL RUNS OF THE HRRR HAVE TENDED TO FAVOR THE CASCADES FOR CONVECTION THIS AFTERNOON AND EVENING...LIKELY STARTING OFF AS SFC-BASED CONVECTION. A COUPLE CONVECTIVE-ALLOWING MODELS ARE ALSO SUGGESTING ANOTHER ROUND OF ELEVATED THUNDER AS THE ABOVE-MENTIONED JET MOVES THROUGH WRN OREGON. EITHER ROUND MAY OR MAY NOT OCCUR...SO DECIDED TO PLAY IT SAFE AND NOT TRY TO GET TOO SPECIFIC ON TIMING. WENT WITH SCATTERED THUNDER TONIGHT LIFTING N-NE AS THE UPPER TROUGH LIFTS INTO WA EARLY MON. THE OVERALL AIR MASS WILL BE CONSIDERABLY DRIER MONDAY AS THE MID- LEVEL THETA-E RIDGE SHIFTS EAST OF THE CASCADES AND FLOW ALOFT TURNS MORE WESTERLY. SURFACE PRESSURE GRADIENTS TURN INCREASINGLY ONSHORE MONDAY...BUT WITH 850 MB TEMPS UPWARDS OF +18 DEG C TEMPS WILL STILL APPROACH 90 FOR MUCH OF THE LOWLANDS. EXPECT SIMILAR WEATHER ON TUESDAY. STRONG UPPER LEVEL HIGH PRESSURE...THE SAME ONE RESPONSIBLE FOR OUR RECENT HEAT...WILL REBUILD ANOTHER RIDGE INTO THE PAC NW MIDWEEK. ODDS ARE GOOD THAT THIS WILL RESULT IN ANOTHER PERIOD OF 90S INLAND AS 500 MB HEIGHTS RISE INTO THE 590S AND 850 MB TEMPS PUSH WELL ABOVE 20 DEG C WITH LITTLE TO NO MARINE INFLUENCE FOR THE INLAND AREAS. WITH NO COOLDOWN IN SIGHT...IT APPEARS TO BE A LOCK FOR MULTIPLE INLAND LOCATIONS IN OUR FORECAST AREA TO BREAK THEIR ALL-TIME RECORDS FOR THE WARMEST JUNE ON RECORD. WEAGLE .LONG TERM...WEDNESDAY NIGHT THROUGH SUNDAY...THE GFS AND THE ECMWF KEEP THE UPPER-LEVEL RIDGE IN PLACE OVER THE WESTERN US THROUGH THE END OF NEXT WEEK. THE ECMWF DOES TRY TO BRING A TROUGH FURTHER SOUTH INTO BRITISH COLUMBIA FRIDAY THROUGH SUNDAY. THIS WOULD TRANSITION US TO MORE ONSHORE FLOW KEEPING TEMPERATURES A BIT LESS HOT NEXT WEEKEND...LOWER 90S INSTEAD OF UPPER 90S IN THE VALLEY. MONSOONAL MOISTURE LOOKS TO STAY FURTHER EAST OF OUR AREA WHICH WILL KEEP US DRY THROUGH THE WEEKEND WITH LOWER HUMIDITY. -MCCOY && .FIRE WEATHER...THE OFFSHORE UPPER LOW IS ROTATING A SWATH OF DRIER AIR ACROSS NORTHERN CALIFORNIA AND IS ABOUT TO CROSS THE OREGON BORDER AT THIS HOUR. THAT BOUNDARY OF MOIST AND DRY MID LEVEL AIR WILL BECOME ORIENTED NEAR THE CASCADE CREST THIS EVENING AND PROVIDE A FOCUS MECHANISM FOR THUNDERSTORM DEVELOPMENT. STILL FEEL LIKE WE ARE WALKING A FINE LINE BETWEEN LAL 2 AND LAL 3 STRIKE COUNTS AND WILL CONTINUE THE RED FLAG WARNING FOR THE CASCADES AND FOOTHILLS DESPITE THE LIMITED CONFIDENCE. COULD GET ISOLATED THUNDERSTORMS FOR AREAS WEST BUT DON`T FEEL THERE WILL BE THE SAME DEGREE OF UPPER LEVEL SUPPORT. ON MONDAY...THERE IS A POSSIBILITY THUNDERSTORMS COULD DEVELOP THROUGH EARLY AFTERNOON OVER THE HIGH CASCADES BUT WILL NEED TO GET HEATING AND MOISTURE TO COME TOGETHER JUST RIGHT. OTHERWISE...THE AIR MASS WILL FINALLY STABILIZE SOMEWHAT AS ONSHORE FLOW INCREASES SOME. UPPER HIGH PRESSURE WILL REMAIN CENTERED OVER THE GREAT BASIN AND MODELS HAVE COME INTO BETTER AGREEMENT WITH REGARD TO KEEPING ANY MONSOONAL MOISTURE SOUTH OF OUR FIRE ZONES AT LEAST THROUGH THURSDAY. TEMPERATURES WILL STILL BE WELL ABOVE NORMAL AND ARE LIKELY TO REMAIN SO. THE VERY WARM...DRY...AND AT LEAST SOMEWHAT UNSTABLE WEATHER NEXT WEEK SHOULD HELP ANY HOLDOVERS MAKE THEIR PRESENCE KNOWN...ESPECIALLY IN THE CASCADES WHERE A SUBSIDENCE INVERSION DEVELOPS AND INTERSECTS THE TERRAIN WITH GREATER INTENSITY OVER TIME. WEAGLE/JBONK && .AVIATION...MARGINALLY UNSTABLE CONDITIONS IN SOUTHERLY FLOW KEPT SOME SCATTERED SHOWER ACTIVITY OVER THE REGION THIS AFTERNOON AND EARLY EVENING. THE SHOWER THREAT APPEARS TO BE MAINLY OVER AT THIS POINT FOR MOST OF THE FCST AREA...ALTHOUGH THERE COULD BE ANOTHER ROUND OF ISOLATED SHOWERS AND THUNDERSTORMS FOCUSED OVER TOWARD THE CASCADES LATER TONIGHT. SHALLOW STRATUS CURRENTLY BRINGING IFR CONDITIONS TO THE CENTRAL OREGON COAST...INCLUDING KONP. THE STRATUS WILL GRADUALLY PUSH NORTHWARD THROUGH THE NIGHT...WITH SOME VISIBILITY RESTRICTIONS AND PATCHY DRIZZLE POSSIBLE OVERNIGHT AND MON MORNING. THE LATEST FCST MODELS ALSO INDICATING THAT CLOUDS WILL TRY TO FORM ALONG THE CASCADE FOOTHILLS OVERNIGHT...BACK BUILDING WESTWARD INTO THE WILLAMETTE VALLEY. THESE CLOUDS MAY BRING A PERIOD OF MVFR CONDITIONS TO SOME OF THE VALLEY TAF SITES...WITH THE BEST CHANCE BETWEEN 12Z AND 16Z MON. THEN EXPECT MOSTLY VFR CONDITIONS LATE MON MORNING AND AFTERNOON. KPDX AND APPROACHES...VFR THROUGH TONIGHT WITH CONSIDERABLE MID AND HIGH CLOUDS...BUT THE SHOWER AND THUNDERSTORM THREAT APPEARS TO BE OVER AT THIS POINT. THE FCST MODELS INDICATE THAT A 2500 TO 3500 FT CLOUD DECK MAY FORM ALONG THE CASCADE FOOTHILLS AND BACK BUILD WESTWARD TOWARD THE TERMINAL EARLY MON MORNING. THIS CLOUD BRING SEVERAL HOURS OF MVFR CONDITIONS. PYLE && .MARINE...LITTLE CHANGE TONIGHT INTO MON...WITH LIGHT S TO SW WINDS OVER THE WATERS...THEN WINDS GRADUALLY TURNING NW LATER MON. WESTERLY SWELL 3 TO 4 FT CONTINUES. OVERALL... WINDS WILL BE BELOW ADVISORY CRITERIA THROUGH MON NIGHT. AFTERWARDS...WILL SEE RETURN OF GUSTY N WINDS AS TYPICAL SUMMER PATTERN SETS UP WITH A THERMAL TROUGH DEVELOPING OVER SW OREGON. && .PQR WATCHES/WARNINGS/ADVISORIES... OR...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR ZONE 605-ZONE 606-ZONE 607-ZONE 608. WA...RED FLAG WARNING UNTIL 11 PM PDT THIS EVENING FOR ZONE 660. PZ...NONE. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
312 AM CDT MON JUN 29 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 312 AM CDT MON JUN 29 2015 LATEST WATER VAPOR SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES AND UPPER LEVEL RIDGE OVER THE WESTERN UNITED STATES INTO THE CANADIAN ROCKIES. SEVERAL PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT PER WATER VAPOR SATELLITE IMAGERY. ONE IMPULSE WAS PRODUCING SHOWERS OVER CENTRAL AND SOUTHWEST WISCONSIN PER KARX RADAR. DUE TO MOIST BOUNDARY LAYER AND MOSTLY CLEAR SKIES PATCHY FOG HAS DEVELOPED OVER PARTS OF THE FORECAST AREA. MAIN FORECAST CONCERNS TODAY INTO THIS EVENING ARE PRECIPITATION CHANCES. THE 29.00Z GFS/NAM INDICATE NEXT SHORTWAVE TROUGH NEAR LAKE WINNIPEG TO IMPACT THE FORECAST AREA THIS AFTERNOON INTO THIS EVENING. THE 29.00Z GFS/NAM SHOW PV ADVECTION IN THE 500-300MB LAYER/STEEP LOW LEVEL LAPSE RATES/INSTABILITY WITH SHORTWAVE TROUGH. THE LATEST HIGH RESOLUTION MODELS...ARW/NMM/HRRR...SHOW DIFFERENCES IN TIMING OF THE CONVECTION INTO THE FORECAST AREA TODAY INTO THIS EVENING. THE 29.00Z DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST CONVECTION WILL DEVELOP MID TO LATE THIS AFTERNOON AND CONTINUE INTO THE EVENING HOURS ACROSS MUCH OF THE FORECAST AREA. HAVE TRENDED THE HIGHER PRECIPITATION CHANCES AFTER 21Z TODAY TO 03Z TUESDAY. THE NEXT CONCERN ARE SEVERE POSSIBILITIES. THE 29.00Z GFS/NAM/RAP SHOW UP TO 20 KNOTS OF 0-3KM SHEAR AND BUFKIT SOUNDINGS INDICATE MANLY STRAIGHT HODOGRAPHS THROUGH THIS LAYER LATE THIS AFTERNOON/THIS EVENING MAINLY WEST OF THE MISSISSIPPI RIVER. THE 29.00Z GFS/NAM AND 29.03Z RAP BUILD UP TO 2000 J/KG OF SURFACE BASE CAPE ACROSS THE FORECAST AREA. WITH WEAK SHEAR IN THE 0-3KM LAYER...LARGE HAIL WILL BE A POSSIBILITY WITH SOME OF THE STRONGER THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 312 AM CDT MON JUN 29 2015 WEAK SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND SHORTWAVE ENERGY PUSHES INTO SOUTHERN/EASTERN WISCONSIN TUESDAY. WITH THE 29.00Z GFS/NAM SUGGEST STEEP LOW LEVEL LAPSE RATE AND THE BETTER INSTABILITY OVER THE EASTERN FORECAST AREA...SMALL PRECIPITATION CHANCES CONTINUE TO BE WARRANTED OVER THIS AREA. THE 29.00Z GFS/NAM/ECMWF ARE TRENDING A FARTHER WESTWARD SOLUTION WITH THE PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT WEDNESDAY INTO WEDNESDAY NIGHT. PLUS...SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND NORTHERN WISCONSIN AND DEVELOP A DRIER NORTHEASTERLY FLOW INTO THE FORECAST AREA. HAVE REDUCE PRECIPITATION CHANCES ACROSS THE WESTERN PORTIONS OF THE FORECAST AREA...BASED ON THE DRIER NORTHEASTERLY FLOW AND WESTERN SHIFT OF THE SHORTWAVE ENERGY. MAIN FORECAST CONCERNS THURSDAY INTO SUNDAY ARE PRECIPITATION CHANCES THROUGH THE PERIOD. THE 29.00Z GFS/ECMWF/GEM ARE IN AGREEMENT IN WEAKENING UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION/EASTERN UNITED STATES AND DEVELOP WEST TO EAST ZONAL FLOW ALOFT BY 12Z SUNDAY ACROSS THE NORTHERN TIER STATES. THE BIGGEST DIFFERENCE BETWEEN THE 29.00Z GFS/ECMWF/GEM IS TIMING OF THE INDIVIDUAL IMPULSES INTO THE GREAT LAKES REGION THROUGH THE FORECAST PERIOD. THE 29.00Z MODELS SUGGEST ENOUGH LIFT/FORCING/MOISTURE CONVERGENCE WITH THE IMPULSES. WILL CONTINUE TREND OF PERIODIC SMALL PRECIPITATION CHANCES THROUGH MUCH OF THE FORECAST PERIOD. TEMPERATURES WILL REMAIN SLIGHTLY BELOW OR NEAR NORMAL DURING THE FORECAST PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1149 PM CDT SUN JUN 28 2015 THE REMAINING SHOWERS ARE NO LONGER NEAR EITHER AIRPORT AND THE SKIES HAVE BEEN CLEARING. WITH THE LIGHT WINDS AND THE EARLIER RAINFALL...APPEARS CONDITIONS ARE FAVORABLE FOR FOG TO FORM OVERNIGHT. SOME SITES ARE ALREADY GOING DOWN TO IFR/MVFR VISIBILITIES AND EXPECT THE FOG WILL FORM AT BOTH TAF SITES WITH PREVAILING VFR CONDITIONS AND SOME OCCASIONAL IFR CEILINGS AND VISIBILITY. THE FOG SHOULD DISSIPATE BY MID MORNING MONDAY WITH VFR CONDITIONS THEN THROUGH THE AFTERNOON. THE NEXT SHORT WAVE TROUGH DROPPING OUT OF CANADA WILL START TO INCREASE THE FORCING ACROSS THE AREA WITH ANOTHER ROUND OF SHOWERS AND STORMS EXPECTED TO FORM. THE 29.00Z CR-NAM NEST...HI-RES ARW AND NMM ALL DEVELOP CONVECTION AHEAD OF THIS WAVE BUT THERE IS CONSIDERABLE DIFFERENCES IN TIMING AMONG THESE MODELS. WILL ADD IN A VCTS FOR BOTH SITES FOR LATE AFTERNOON THROUGH THE EVENING AND LET LATER FORECASTS REFINE THE TIMING ON THE STORMS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DTJ LONG TERM...DTJ AVIATION...04
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
931 AM EDT MON JUN 29 2015 .DISCUSSION...FRONTAL BOUNDARY WILL REMAIN STALLED JUST NORTH OF FL WITH ATL RIDGE AXIS SOUTH OF THE AREA...KEEPING DEEP W/SW FLOW OVER CENTRAL FL. CONVECTION OVER THE NE GULF IS PUSHING ONSHORE THE BIG BEND/NATURE COAST REGION OF WEST FL AND THIS ACTIVITY WILL BEGIN TO MOVE INTO LAKE COUNTY AND TOWARD THE I-4 CORRIDOR THIS MORNING. DEEP MOISTURE ASSOCIATED WITH THIS SYSTEM WILL MOVE ACROSS THE REGION WITH BOTH THE HRRR AND WRF SHOWING HIGH COVERAGE OF SHOWERS AND STORMS INTO THE AFT. MOS POPS ALSO CONTINUE TO REMAIN HIGH SO WILL KEEP LIKELY POPS (60-70 PERCENT) IN FOR MUCH OF THE REGION. A FEW STRONGER STORMS CAN NOT BE RULED OUT WITH FREQUENT LIGHTNING...STRONG WIND GUSTS AND SMALL HAIL THE MAIN THREATS. CLOUD COVER WILL BEGIN INCREASING OVER AREAS FROM ORLANDO NORTH INTO THE MORNING WHICH SHOULD LIMIT HIGHS IN THE UPPER 80S TO AROUND 90 DEGREES. HOWEVER FARTHER SOUTH WHERE MORE SUNSHINE IS EXPECTED...MAX TEMPS WILL EASILY REACH THE LOW 90S AND EVEN MID 90S ALONG PORTIONS OF THE COAST...SOUTH OF THE CAPE...AS SEA BREEZE IS NOT EXPECTED TO FORM FROM STRONGER OFFSHORE FLOW. && .AVIATION...CONVECTION ALREADY PUSHING INTO LAKE COUNTY THIS MORNING WITH SHOWERS AND STORMS INCREASING ACROSS THE AREA FROM LATE MORNING INTO THE AFTERNOON...BECOMING SCATTERED TO NUMEROUS. TEMPO IFR/MVFR CONDS ARE EXPECTED WITH THIS ACTIVITY AS IT MOVES EASTWARD ACROSS THE REGION AND OFFSHORE INTO THIS EVENING. SOME STORMS WILL PRODUCE STRONG GUSTY WINDS. && .MARINE... TODAY-TONIGHT...WEST TO SOUTHWEST WINDS UP TO 10 TO 15 KNOTS ARE EXPECTED ACROSS THE WATERS AS THE AREA REMAINS BETWEEN FRONTAL BOUNDARY TO THE NORTH AND RIDGE AXIS TO THE SOUTH. OFFSHORE FLOW SHOULD REMAIN STRONG ENOUGH TO PREVENT EAST COAST SEA BREEZE FROM DEVELOPING THIS AFTERNOON. SEAS WILL GENERALLY RANGE FROM 1-2 FEET NEARSHORE AND 2-3 FEET OFFSHORE. MAIN CONCERN FOR BOATERS WILL BE FOR STRONGER OFFSHORE MOVING STORMS FROM LATE MORNING INTO THE AFTERNOON...PRODUCING GUSTY WINDS. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ WEITLICH/VOLKMER
FORECAST DISCUSSION SEEMING A BIT REPETITIVE AS CENTRAL ILLINOIS
REMAINS IN A LARGELY NORTHWESTERLY FLOW PATTERN FOR THE FCST PD. A
STEADY STREAM OF SHORT WAVES INTO THE REGION KEEP POPS FOR OCCASIONAL SHOWERS AND THUNDERSTORMS IN THE FORECAST. SOME TIMING ISSUES REMAIN FROM RUN TO RUN. FORECAST KEEPS SOME POPS IN TONIGHT, MAINLY FOR THE NORTH AND EAST CLOSER TO THE SFC LOW...AND INCREASING TOWARDS MORNING WITH ANOTHER WAVE DIVING INTO THE MIDWEST IN NAM AND GFS SOLUTIONS, WITH A BREAK TUES NIGHT POSSIBLE FOR THE NORTH BEFORE ANOTHER WAVE ON WED AND SO ON THROUGH MOST OF THE FORECAST. WED/WED NIGHT IS CURRENTLY SOME OF THE MORE FOCUSED POPS AS A BOUNDARY IS APPARENT IN SFC WIND FIELDS IN THE MODELS. ANY BOUNDARY LIKELY TO SET UP IN THE REGION WILL PROVIDE MORE FOCUS/DYNAMICS FOR ANY SHORT WAVE ASSISTED CONVECTION THAT DOES FORM. THE SERIES OF WAVES STARTS TO HAVE A LITTLE MORE DISSONANCE FROM MODEL TO MODEL GOING INTO THE EXTENDED AS EXPECTED WITH REGARDS TO TIMING. OVERALL THE FORECAST REMAINS WET AND STORMY WITH TEMPS SLIGHTLY BELOW NORMAL WITH NORTHWESTERLY FLOW. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 650 AM CDT MON JUN 29 2015 IFR AND MVFR CONDITIONS PREVAIL AT ALL TAF SITES THIS MORNING. THIS STRATUS WILL NOT BE AROUND LONG GIVEN THAT CLOUD DECK IS NOT THAT THICK AND SHOULD BURN OFF RATHER QUICKLY. SO HAVE THINGS IMPROVING 14-15Z AT ALL SITES AND THEN CLOUDS WILL SCATTER OUT THIS EVENING. ONCE THE LOW PRESSURE AREA MOVES EAST OF THE AREA WINDS AT ALL SITES WILL BE OUT OF THE NORTHWEST MOST OF THE DAY...AND THEN TURN WESTERLY THIS EVENING. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...BARNES SHORT TERM...HJS LONG TERM...HJS AVIATION...AUTEN
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
659 AM EDT MON JUN 29 2015 .SYNOPSIS... ISSUED AT 446 AM EDT MON JUN 29 2015 LOW PRESSURE WILL DRIFT ACROSS NORTHERN INDIANA TODAY...BRINGING YET ANOTHER CHANCE FOR SHOWERS AND A FEW STORMS. AS THE LOW MOVES AWAY THIS EVENING A BRIEF DRY PERIOD IS IN STORE PRIOR TO THE ARRIVAL OF THE NEXT CHANCE FOR RAIN ON TUESDAY. HIGHS TODAY WILL BE IN THE LOWER 70S WITH LOWS TONIGHT DROPPING INTO THE UPPER 50S TO LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 446 AM EDT MON JUN 29 2015 THE TRAIN OF WAVES CONTINUES WITH ONE UPPER LEVEL SYSTEM NOW PASSING ACROSS THE SOUTHERN GREAT LAKES/N OHIO VALLEY WITH SCATTERED TO NUMEROUS SHOWERS AND A FEW STORMS. COVERAGE SO FAR HAS STRUGGLED ACROSS THE FORECAST AREA WITH SOME SMALL AREAS OF SHOWERS MOVING GENERALLY ALONG AND SOUTH OF US 24. TRENDS TO THE WEST WOULD SUGGEST THAT RAINFALL CHANCES MAY DIMINISH QUICKLY THIS MORNING WITH THE MAIN FOCUS ON SE/E SECTIONS THAT HAVE SEEN TOO MUCH RAIN ALREADY. A FEW OF THE HIGH RES MODELS PRINT OUT THREE QUARTERS TO OVER AN INCH OF RAIN (6Z RAP WENT TO EXTREME OF SWATH OF 1 TO 2 INCHES OF RAIN FROM GRANT COUNTY NE TO FT WAYNE). GIVEN LIKELIHOOD OF DEFORMATION ZONE OF MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL SETTING UP IN EASTERN AREAS...RAINFALL AMOUNTS COULD BE REALIZED. HOWEVER...PWATS NOT AS HIGH AS PAST SYSTEMS AND WHILE BRIEFLY SLOWING THE SYSTEM WILL BE SOMEWHAT MORE PROGRESSIVE IN NATURE. WITH MUCH OF THE AREA OF CONCERN ALREADY COVERED BY AREAL FLOOD WARNING THAT WILL LIKELY BE EXTENDED HOISTING A WATCH FOR THOSE AREAS SERVES NO PURPOSE. IN LOCATIONS FURTHER SOUTHWEST...ARGUMENT COULD BE MADE TO HOIST THE WATCH...BUT EQUAL ARGUMENT (AND MAYBE BETTER APPROACH) COULD BE TO EXPAND/ISSUE AREAL FLOOD WARNING VS A FLOOD WATCH. WILL MONITOR TRENDS NEXT COUPLE OF HOURS. TEMPERATURES WERE LOWERED SOMEWHAT TODAY WITH CLOUDS AND PRECIP BUT MAY STILL BE TOO WARM. BEST POTENTIAL FOR HEATING MAY BE IN SW AREAS THAT COULD SEE SOME BREAKS IN THE CLOUDS BY LATE AFTERNOON AS THE SFC LOW PASSES OVERHEAD. PRECIP MAY LINGER IN THE EAST INTO THE EVENING BUT SHOULD PUSH OUT RATHER QUICKLY AS SMALL AREA OF SUBSIDENCE SHIFTS IN LATE EVENING INTO PART OF THE OVERNIGHT HOURS BEFORE THE NEXT WAVE APPROACHES. KEPT SLGT CHC POPS THROUGH THE NIGHT WITH INCREASE IN THE WEST TOWARDS DAYBREAK. LOWS WILL DROP INTO THE UPPER 50S TO LOWER 60S. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 446 AM EDT MON JUN 29 2015 SHRTWV OVER MANITOBA THIS MORNING EXPECTED TO DROP SE TO NE IL BY 12Z TUE THEN SWING EAST THROUGH BASE OF TROF ACROSS NRN INDIANA DURING THE DAY. MODELS SUGGEST FAIRLY STRONG FORCING AND WK-MOD INSTABILITY WILL ACCOMPANY THIS SYSTEM TUE...SO SCT-NUMEROUS SHOWERS/TSTMS LIKELY. SFC CDFNT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO MOVE SLOWLY SE ACROSS OUR CWA TUE NGT-WED NGT AS ANOTHER SHRTWV MOVES SE FROM THE NRN PLAINS TO THE LWR OH VALLEY. THIS MAY CAUSE SCT SHOWERS/TSTMS TO CONT IN THE CWA WITH BEST CHANCES ACROSS SRN PORTIONS OF THE AREA IN CLOSEST PROXIMITY TO THE SLOW MOVG SFC BOUNDARY. CURRENT AMPLIFIED UPR AIR PATTERN WITH STRONG RIDGE IN WRN NORTH AMERICA AND TROF FROM HUDSON BAY THROUGH THE GRTLKS EXPECTED TO TRANSITION TO A MORE ZONAL FLOW LATE IN THE PERIOD AS GULF OF ALASKA CLOSED LOW GETS KICKED EAST INTO WRN CANADA WKNG RIDGE IN THAT AREA. STILL... A WK BROAD TROF EXPECTED TO PERSIST ACROSS THE GRTLKS THROUGH THE PERIOD WITH AN E-W ORIENTED STNRY SFC BOUNDARY LIKELY CONTG JUST SOUTH OF OUR CWA. ALSO APPEARS THAT SOME WK SHRTWVS WILL TOP WRN RIDGE AND MOVE SE TOWARD BASE OF THE BROAD TROF OVER OUR AREA IN THIS TIMEFRAME. THUS... A SMALL CHANCE OF SHOWERS/TSTMS CONTS FOR MUCH OF THE LONG TERM PERIOD. THIS SCENARIO ALSO SUPPORTS A CONTINUATION OF TEMPS SLIGHTLY BLO NORMAL THROUGH THIS PERIOD... THOUGH A WARMUP EXPECTED NEXT WEEKEND AS FLOW ALOFT BECOMES MORE ZONAL AND LOW LEVEL SOUTHERLY WINDS RETURN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 653 AM EDT MON JUN 29 2015 LOW PRESSURE MOVG EAST ACROSS CENTRAL INDIANA WAS CAUSING AN AREA OF RAIN WITH LOW CIGS TO SPREAD INTO NRN INDIANA. MAINLY MVFR CONDITIONS EXPECTED WITH A PERIOD OF IFR LIKELY AT FWA MIDDAY. CONDITIONS SHOULD IMPROVE THIS EVE AS THE LOW MOVES EAST BUT LIGHT WINDS AND MOIST LOW LEVELS OVERNIGHT SHOULD CAUSE SOME STRATUS/FOG TO DEVELOP TOWARD DAYBREAK WITH IFR CONDITIONS PSBL. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...FISHER SHORT TERM...FISHER LONG TERM...JT AVIATION...JT VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
840 AM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 839 AM CDT MON JUN 29 2015 VISIBILITIES HAVE RAPIDLY IMPROVED OVER MUCH OF THE AREA SINCE 7 AM. MOST OF THE DENSE FOG ADVISORY HAS BEEN CANCELLED. THOSE AREAS THAT HAVE NOT BEEN CANCELLED WILL EXPIRE AT 9 AM. UPDATE ISSUED AT 424 AM CDT MON JUN 29 2015 LOOKING AT WEB CAMS AND OBSERVATION SITES HAS INDICATED THE FOG HAS WORSENED AND MANY LOCATIONS ARE SOCKED IN WITH VISIBILITIES OF 1/4 MILE OR LESS. THEREFORE...I HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA UNTIL 9 AM. IF THE FOG DISSIPATES SOONER THAN THE ADVISORY CAN BE CANCELLED. && .SYNOPSIS... ISSUED AT 345 AM CDT MON JUN 29 2015 LIGHT TO CALM WINDS AND WET GROUND HAS LED TO THE DEVELOPMENT OF GROUND FOG ACROSS MUCH OF THE CWA. LOOKING AT WEB CAMS AND OBSERVATIONS THE VISIBILITIES WERE HIGHLY VARIABLE AND A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THIS SITUATION. 3 AM TEMPERATURES WERE IN THE MID 50S NORTH TO MID 60S SOUTH ACROSS THE CWA. A WEAK VORT MAX IN WI WAS CAUSING A FEW SHOWERS THERE WHILE A STRONGER SHORT WAVE WAS SEEN ON WATER VAPOR LOOPS IN MANITOBA AND DROPPING SOUTHWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON JUN 29 2015 FORECAST FOCUS ON RAIN CHANCES. TODAY...AREAS OF FOG SHOULD DISSIPATE BY 8 AM OR SO AND THEN ATTENTION TURNS TO CHANCES FOR SHOWERS AND THUNDERSTORMS. WILL MENTION SLIGHT CHANCES FOR SHOWERS THIS MORNING AND THEN INCREASE POPS THIS AFTERNOON FOR THUNDERSTORMS. FORECAST SOUNDINGS INDICATE WE REACH CONVECTIVE TEMPERATURES BY AROUND NOON WITH STEEPENING LAPSE RATES...AND NO CAP IN PLACE. THE HRRR INDICATES SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF THE CWA THIS AFTERNOON WHILE OTHER MODELS ARE FAIRLY SIMILAR. THE SEVERE HAILERS SHOULD REMAIN NORTH ACROSS MN AND WESTERN WI AIDED BY THE DECENT MANITOBA WAVE AND COLDER AIR ALOFT. HOWEVER...SOME OF THESE STORMS MAY DRIFT INTO NORTHEAST IA LATER THIS AFTERNOON AND EARLY EVENING WITH THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS. SHEAR IS WEAK AND SBCAPES ARE PROGGED AT 1000-2000 J/KG. HOWEVER...IF TEMPERATURES CAN WARM MORE THAN EXPECTED THAN AN ISOLATED LARGE HAIL IS NOT OUT OF THE QUESTION WITH FREEZING LEVELS AT 11K FT. SPC HAS A MARGINAL RISK FOR THE POTENTIAL FOR STRONGER STORMS IN OUR NW CWA. THERE SHOULD BE PLENTY OF CLOUD COVER AGAIN WITH SOME PEEKS OF SUNSHINE. THIS WILL KEEP AFTERNOON TEMPERATURES IN THE 70S AT MOST LOCATIONS. TONIGHT...AT LEAST SCATTERED SHOWERS AND STORMS THIS EVENING WILL GRADUALLY DIMINISH WITH LOSS OF HEATING LATER THIS EVENING. THEN WILL CARRY SMALL POPS AFTER MIDNIGHT AS THE NAM/GFS INDICATE SOME LINGERING QPF WITH ANY WEAK VORT MAX IN THE DEEP NORTHWEST FLOW. HOWEVER...THE ECMWF IS COMPLETELY DRY THIS EVENING AND OVERNIGHT. MINIMUM TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON JUN 29 2015 NOT MUCH CHANGE IN THE OVERALL PATTERN WITH NORTHWEST FLOW ALOFT TO PREVAIL THROUGH MUCH OF THE PERIOD KEEPING TEMPS NEAR TO BELOW NORMAL WHILE ALSO LIMITING ANY ORGANIZED SEVERE POTENTIAL. WILL SEE PERIODIC RAIN CHANCES AS SEVERAL UPPER LEVEL DISTURBANCES TRANSVERSE THE REGION. ONE SUCH DISTURBANCE OFF THE PACIFIC NW COAST EARLY THIS AM FAIRLY VIGOROUS LOOKING PER SATELLITE REPRESENTATION. THIS ENERGY WILL CREST THE WESTERN HEAT DOME NEXT 24 HOURS THEN HEAD SE AND INTERACT WITH IMPRESSIVE LOW LEVEL MOISTURE CONVERGENCE AND BAROCLINIC ZONE (SQUEEZED BETWEEN DRIER EASTERLY FLOW OFF LAKE MI AND ADVECTION OF DRIER AIR WITH SOUTHWEST FLOW OFF EASTERN ROCKIES INTO KS) FOR WIDESPREAD SHOWERS AND STORMS WITH POTENTIAL FOR HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE MAIN CHALLENGE IS JUST WHERE DOES THIS BATTLE ZONE AND HIGHER PROBABILITIES OF PRECIP AND HEAVY RAIN SET UP. LAST SEVERAL RUNS OF GFS TRENDING FROM SOUTH OF I-70 TO NEAR THE IA/MO BORDER CLOSER TO LAST FEW RUNS OF NAM. MEANWHILE...THE ECMWF IS A BIT STRONGER WITH THE GREAT LAKES HIGH AND CONSEQUENTLY WITH THE DRIER EASTERLY FLOW... AND IS ALSO SLOWER WITH MAIN SURGE OF MOISTURE FOCUSING MORE LATER WEDNESDAY AND WEDNESDAY NIGHT NEAR THE FAR SOUTHERN CWA AND ESPECIALLY JUST SOUTH/WEST OF CWA. GIVEN THE STRENGTH OF FORCING WOULD ANTICIPATE THE THREAT FOR RAINFALL AMOUNTS OF 1-2+ INCHES WHERE THIS SETS UP AND WILL NEED TO BE WATCHED VERY CAREFULLY FOR SOUTHERN CWA WHERE GROUND IS SATURATED AND RIVER LEVELS HIGH FROM SEVERAL ROUNDS OF HEAVY RAINFALL WITHIN THE PAST WEEK OR SO. GIVEN THE MODEL CONSISTENCY AND TIMING ISSUES I HAVE KEPT POPS IN THE CHANCE CATEGORY FOR NOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGHEST FAR SOUTH. IN THE WAKE OF THIS SYSTEM WOULD ANTICIPATE 24+ HRS OF DRY AND PLEASANT WEATHER THURSDAY POSSIBLY INTO FRIDAY WITH SURFACE RIDGING AND EASTERLY FLOW. THEN...OPERATIONAL GFS AND MANY OF GFS ENSEMBLE MEMBERS ALONG WITH HI-RES ECMWF SUGGEST ANOTHER DISTURBANCE ACCOMPANIED BY RAIN CHANCES ESPECIALLY THE SOUTHERN CWA DEVELOPING FRIDAY AND LINGERING INTO FRIDAY NIGHT. IF THIS TIMING HOLDS THEN HAVE AN OPPORTUNITY TO SNEAK IN A DRY AND SEASONABLE 4TH OF JULY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 449 AM CDT MON JUN 29 2015 WIDESPREAD LIFR CONDS IN FG TIL 14Z/29. THEN VFR CONDS WITH SCATTERED SHOWERS AND THUNDERSTORMS THIS AFTERNOON AND EVENING. NORTHWEST WINDS AROUND 10 KNOTS OR LESS. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR CLINTON- JACKSON-SCOTT. IL...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BUREAU- CARROLL-HENRY IL-JO DAVIESS-PUTNAM-ROCK ISLAND-STEPHENSON- WHITESIDE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...HAASE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
900 AM MDT MON JUN 29 2015 .UPDATE... ISSUED AT 859 AM MDT MON JUN 29 2015 UPDATED FORECAST TO BETTER REFLECT THE LIGHT RAIN SHOWERS MOVING SOUTH-SOUTHEAST MAINLY THROUGH FAR EAST CENTRAL COLORADO AND FAR WESTERN KANSAS THIS MORNING. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 241 AM MDT MON JUN 29 2015 NORTHERLY FLOW WILL CONTINUE ACROSS THE PLAINS EAST OF THE ROCKIES AS A RIDGE PERSISTS OVER CENTRAL UTAH. BY WEDNESDAY THE RIDGE RETROGRESSES TO NEVADA. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE AREA TODAY AND TONIGHT. THE HIGH WILL BE REPLACED BY WEAK LOW PRESSURE TUESDAY AND TUESDAY NIGHT. A SURFACE TROUGH WILL SHIFT EAST ACROSS NORTHWEST KANSAS WEDNESDAY FOLLOWED BY HIGH PRESSURE WEDNESDAY NIGHT. PLAN ON CHANCE AND SLIGHT CHANCE POPS ACROSS THE WESTERN PORTION OF THE FA TODAY AND INTO EARLY THIS EVENING. THE NAM AND THE HRRR HAVE A GOOD HANDLE ON STORMS DEVELOPING EARLY THIS MORNING. THE MODELS ARE ALSO INDICATING STORMS THIS AFTERNOON. DYNAMICS SHOULD SLOWLY MOVE TO THE SOUTHWEST FA EARLY THIS EVENING WITH POPS DECREASING TO NIL VALUES. POPS WILL REMAIN NIL OVERNIGHT AND TUESDAY. A SHORTWAVE MOVES THROUGH THE FLOW LATE TUESDAY EVENING. SLIGHT CHANCE LOOKS ON TRACK FOR THAT TIME PERIOD SINCE MOISTURE REMAINS LIMITED. STORMS WEDNESDAY AFTERNOON AND EVENING SHOULD BE CONFINED TO THE FRONTAL BOUNDARY OVER EASTERN COLORADO. ONCE AGAIN MOISTURE IS LIMITED SO SLIGHT CHANCE POPS SHOULD BE APPROPRIATE. MAX TEMPERATURES TODAY AND WEDNESDAY SHOULD RISE INTO THE LOWER 90S IN THE WESTERN FA AND THE UPPER 90S (SIMILAR TO YESTERDAY) IN THE EAST. 850 TEMPERATURES WILL SUPPORT SURFACE TEMPERATURES NEAR 100 DEGREES TUESDAY. APPARENT TEMPERATURES ARE NOT AT HEAT ADVISORY LEVELS BUT THIS WILL NEED TO BE MONITORED. MIN TEMPERATURES SHOULD RANGE FROM 65 TO 70 WITH COOLEST READINGS IN EASTERN COLORADO. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 241 AM MDT MON JUN 29 2015 THE BEST CHANCES FOR PRECIP ARE AT THE START OF THE PERIOD ON THURSDAY AND FRIDAY AS AN UPPER LEVEL TROUGH PASSES ACROSS THE NORTHERN PLAINS AND A FRONTAL BOUNDARY STALLS OUT OVER THE AREA. MEANWHILE...THE UPPER LEVEL RIDGE OVER THE WESTERN HALF OF THE CONUS WILL CONTINUE TO BREAK DOWN. DRIER AIR IS EXPECTED TO MOVE INTO THE NORTHERN PORTION OF THE FORECAST AREA ON FRIDAY AND PROGRESS SOUTH. DRY CONDITIONS LOOK TO PERSIST FOR MUCH OF THE HIGH PLAINS FOR THE WEEKEND AS THE UPPER LEVEL RIDGE SOMEWHAT REBOUNDS ALTHOUGH SOME WEAK DISTURBANCES COULD GENERATE PRECIP CHANCES FOR PARTS OF THE AREA. HIGHS ON THURSDAY ARE EXPECTED TO BE IN THE 80S...COOLING A COUPLE DEGREES ON FRIDAY BEFORE REBOUNDING INTO THE MID 80S TO MID 90S FOR THE WEEKEND AS THE RIDGE REBUILDS. LOWS ARE FORECAST IN THE UPPER 50S TO MID 60S THURSDAY NIGHT AND FRIDAY NIGHT. TEMPERATURES FOR SATURDAY NIGHT LOOK TO BE SLIGHTLY WARMER AND IN THE 60S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 455 AM MDT MON JUN 29 2015 VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK FOR THE NEXT 24 HOURS. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM TODAY AT KGLD WITH ALMOST NO CHANCE BY EARLY EVENING. WINDS WILL BE LIGHT AND VARIABLE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...LOCKHART SHORT TERM...FS LONG TERM...JBH AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
502 AM MDT MON JUN 29 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 241 AM MDT MON JUN 29 2015 NORTHERLY FLOW WILL CONTINUE ACROSS THE PLAINS EAST OF THE ROCKIES AS A RIDGE PERSISTS OVER CENTRAL UTAH. BY WEDNESDAY THE RIDGE RETROGRESSES TO NEVADA. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE AREA TODAY AND TONIGHT. THE HIGH WILL BE REPLACED BY WEAK LOW PRESSURE TUESDAY AND TUESDAY NIGHT. A SURFACE TROUGH WILL SHIFT EAST ACROSS NORTHWEST KANSAS WEDNESDAY FOLLOWED BY HIGH PRESSURE WEDNESDAY NIGHT. PLAN ON CHANCE AND SLIGHT CHANCE POPS ACROSS THE WESTERN PORTION OF THE FA TODAY AND INTO EARLY THIS EVENING. THE NAM AND THE HRRR HAVE A GOOD HANDLE ON STORMS DEVELOPING EARLY THIS MORNING. THE MODELS ARE ALSO INDICATING STORMS THIS AFTERNOON. DYNAMICS SHOULD SLOWLY MOVE TO THE SOUTHWEST FA EARLY THIS EVENING WITH POPS DECREASING TO NIL VALUES. POPS WILL REMAIN NIL OVERNIGHT AND TUESDAY. A SHORTWAVE MOVES THROUGH THE FLOW LATE TUESDAY EVENING. SLIGHT CHANCE LOOKS ON TRACK FOR THAT TIME PERIOD SINCE MOISTURE REMAINS LIMITED. STORMS WEDNESDAY AFTERNOON AND EVENING SHOULD BE CONFINED TO THE FRONTAL BOUNDARY OVER EASTERN COLORADO. ONCE AGAIN MOISTURE IS LIMITED SO SLIGHT CHANCE POPS SHOULD BE APPROPRIATE. MAX TEMPERATURES TODAY AND WEDNESDAY SHOULD RISE INTO THE LOWER 90S IN THE WESTERN FA AND THE UPPER 90S (SIMILAR TO YESTERDAY) IN THE EAST. 850 TEMPERATURES WILL SUPPORT SURFACE TEMPERATURES NEAR 100 DEGREES TUESDAY. APPARENT TEMPERATURES ARE NOT AT HEAT ADVISORY LEVELS BUT THIS WILL NEED TO BE MONITORED. MIN TEMPERATURES SHOULD RANGE FROM 65 TO 70 WITH COOLEST READINGS IN EASTERN COLORADO. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 241 AM MDT MON JUN 29 2015 THE BEST CHANCES FOR PRECIP ARE AT THE START OF THE PERIOD ON THURSDAY AND FRIDAY AS AN UPPER LEVEL TROUGH PASSES ACROSS THE NORTHERN PLAINS AND A FRONTAL BOUNDARY STALLS OUT OVER THE AREA. MEANWHILE...THE UPPER LEVEL RIDGE OVER THE WESTERN HALF OF THE CONUS WILL CONTINUE TO BREAK DOWN. DRIER AIR IS EXPECTED TO MOVE INTO THE NORTHERN PORTION OF THE FORECAST AREA ON FRIDAY AND PROGRESS SOUTH. DRY CONDITIONS LOOK TO PERSIST FOR MUCH OF THE HIGH PLAINS FOR THE WEEKEND AS THE UPPER LEVEL RIDGE SOMEWHAT REBOUNDS ALTHOUGH SOME WEAK DISTURBANCES COULD GENERATE PRECIP CHANCES FOR PARTS OF THE AREA. HIGHS ON THURSDAY ARE EXPECTED TO BE IN THE 80S...COOLING A COUPLE DEGREES ON FRIDAY BEFORE REBOUNDING INTO THE MID 80S TO MID 90S FOR THE WEEKEND AS THE RIDGE REBUILDS. LOWS ARE FORECAST IN THE UPPER 50S TO MID 60S THURSDAY NIGHT AND FRIDAY NIGHT. TEMPERATURES FOR SATURDAY NIGHT LOOK TO BE SLIGHTLY WARMER AND IN THE 60S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 455 AM MDT MON JUN 29 2015 VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK FOR THE NEXT 24 HOURS. THERE IS A SLIGHT CHANCE OF A THUNDERSTORM TODAY AT KGLD WITH ALMOST NO CHANCE BY EARLY EVENING. WINDS WILL BE LIGHT AND VARIABLE. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...FS LONG TERM...JBH AVIATION...FS
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1112 AM EDT MON JUN 29 2015 .UPDATE... ISSUED AT 1112 AM EDT MON JUN 29 2015 THE FORECAST REMAINS ON TRACK TODAY. THE FIRST SHORT WAVE TROUGH...WITH THE MAJORITY OF ITS ASSOCIATED FORCING NORTH OF THE OHIO RIVER...IS ON ITS WAY OUT. WE NOW AWAIT THE NEXT WAVE TO COME IN FROM THE NORTHWEST...WHICH COMBINED WITH HEATING AND SOME SURFACE CONVERGENCE WILL ALLOW FOR ANOTHER ROUND OF SCATTERED CONVECTION. AN ISOLATED SEVERE STORM IS STILL A POSSIBILITY... DEPENDING ON HOW MUCH INSTABILITY CAN BUILD IN THIS AFTERNOON. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 745 AM EDT MON JUN 29 2015 FORECAST WAS NOT IN TOO BAD OF SHAPE. BROUGHT THE GRIDS IN LINE WITH LATEST RADAR TRENDS AND HOURLY OBS. SOUTHERN END OF BAND OF SHOWERS IS STRUGGLING TO HOLD TOGETHER...BUT THERE HAS BEEN SOME REDEVELOPMENT OVER THE PAST HOUR. BASED ON RADAR MOSAIC...HIGHEST POPS IN THE NORTH AND ESPECIALLY I-64 CORRIDOR LOOKS RIGHT ON TARGET FOR THE START OF THE MORNING. WITH ADDITIONAL SHORTWAVE ENERGY DROPPING INTO THE BASE OF OUR OVERHEAD TROUGH...STILL EXPECTING REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON...LINGERING INTO THE EARLY EVENING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 417 AM EDT MON JUN 29 2015 HIGH AMPLITUDE PATTERN ALOFT WILL MEAN EASTERN CONUS TROUGH WILL DOMINATE OUR WEATHER THROUGH THE SHORT TERM. BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SFC FRONTAL SYSTEM CONTINUES TO MOVE EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. MODELS...AND ESPECIALLY THE HRRR SUGGEST THAT THIS ACTIVITY WILL GRADUALLY WEAKEN AS IT MOVES INTO OUR AREA AROUND DAWN...DUE TO UPPER LEVEL SUPPORT SHEARING OUT. HOWEVER...ADDITIONAL SHORTWAVE ENERGY ALOFT ROUNDING THE BASE OF AN EASTERN CONUS TROUGH SHOULD HELP REGENERATE ACTIVITY THROUGH THE AFTERNOON. SHEAR AND INSTABILITY APPEAR SUFFICIENT FOR THE THREAT OF SOME STRONG TO SEVERE THUNDERSTORMS...MAINLY THROUGH THE AFTERNOON AND EARLY EVENING. BUT THERE ARE SOME LIMITING FACTORS FOR EXAMPLE... CLOUD COVER...LESS THAN IMPRESSIVE MID LEVEL LAPSE RATES...AND FORCING...THE STRONGEST OF WHICH MAY REMAIN FURTHER NORTH AND WEST OF OUR AREA. THEREFORE SEVERE THREAT MAY BE MORE ISOLD IN NATURE WITH RESPECT TO COVERAGE. JUST THE SAME WITH SPC PLACING OUR AREA IN A SLIGHT RISK TODAY WILL CONTINUE TO ADVERTISE THE POTENTIAL. WITH THE APPROACH OF THE SFC TROUGH TO OUR WEST AND MID LEVEL CLOUD COVER CURRENTLY MOVING INTO OUR AREA EXPECT TEMPERATURES TO BEGIN TO REBOUND ACROSS MUCH OF THE AREA BETWEEN NOW AND SUNRISE. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 351 AM EDT MON JUN 29 2015 UPPER LEVEL MODELS CONTINUE TO SUPPORT A LONGWAVE TROUGH ACROSS MUCH OF THE EASTERN CONUS TO START OFF THE PERIOD...KEEPING THE OHIO RIVER VALLEY IN NW FLOW REGIME FROM TUESDAY NIGHT THROUGH FRIDAY. THE AXIS OF THE TROUGH WILL THEN SHIFT DIRECTLY OVER KY AS ANOTHER SHORTWAVE DIGS SOUTHWARD FROM CANADA TO START OFF THE WEEKEND. FINALLY...THE UPPER LEVEL LONGWAVE PATTERN WILL SLOWLY DAMPEN AS WE HEAD INTO THE END OF THE EXTENDED PERIOD SUNDAY INTO MONDAY. HOWEVER...BY THE WEEKEND MODELS SHOW QUITE A BIT OF DISCONTINUITY...SO THE EXACT TIMING AND MAGNITUDE OF THE UPPER LEVEL TROUGH WILL BE SOMEWHAT LOW CONFIDENCE. WITH THE GENERAL NW FLOW...EXPECT SHORTWAVES TO CONTINUE TO TRAVEL SE AND INTO THE OHIO RIVER VALLEY. THIS WILL RESULT IN SEVERAL SURFACE LOW PRESSURE CENTERS AND FRONTAL BOUNDARIES PASSING THROUGH THE REGION...CREATING THE ENERGY AND LIFT TO PRODUCE SHOWERS AND THUNDERSTORMS. AS HAS BEEN THE CASE OVER THE LAST FEW WEEKS...EXPECT MOST WIDESPREAD ACTIVITY TO BE RIGHT ALONG AND JUST AHEAD OF THE FRONTAL BOUNDARY...PEAKING IN SEVERITY DURING THE AFTERNOON AND EARLY EVENING HOURS IN CONJUNCTION WITH THE PEAK HEATING. THE FIRST OF THESE BOUNDARIES WILL BE EXITING TUESDAY NIGHT AS THE NEXT BOUNDARY TO OUR NORTH MAKES A SHIFT SOUTHWARD. THIS SECOND BOUNDARY IS EXPECTED TO MAKE IT INTO THE REGION WEDNESDAY NIGHT...AND ACCORDING TO THE LATEST 00Z RUN OF THE GFS40...SHOULD BECOME STALLED OUT ACROSS THE REGION THROUGH THE DAY FRIDAY AS THE UPPER LEVEL TROUGH BACK-BUILDS ACROSS THE OHIO RIVER VALLEY. ALONG THIS BOUNDARY...EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...WITH ANY UPPER LEVEL WAVES OF ENERGY ENHANCING CHANCES FOR A MCS TO PASS THROUGH THE REGION. THE FRONTAL BOUNDARY WILL FINALLY SHIFT SE OF THE STATE BY FRIDAY EVENING...ASSUMING MODEL TIMING PANS OUT. UNFORTUNATELY...ANOTHER WEAK FRONTAL BOUNDARY WILL HAVE FORMED TO OUR NORTH...AND WE WILL STILL BE IN VERY CLOSE PROXIMITY TO THE EXITING FRONT. UNDER SW FLOW BY THIS POINT...AND STILL IN AN UPPER LEVEL LOW PRESSURE TROUGHING PATTERN...EXPECT LESS ORGANIZED SCATTERED CONVECTION TO CONTINUE INTO THE WEEKEND...WITH BEST CHANCES STILL EXPECTED OVER THE SE CWA CLOSER TO THE EXITING FRONT. BY SUNDAY...MODEL CONFIDENCE IN CONVECTION STARTS TO DECLINE AS THERE IS LITTLE AGREEMENT IN THE PATTERN ALOFT. IF THE GFS IS CORRECT...THE UPPER LEVEL TROUGH WILL BEGIN DAMPENING/WEAKENING... BUT CONTINUED WARM SW FLOW AND A PASSING SHORTWAVE COULD BE THE SPARK FOR YET MORE SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON/EVENING HOURS. BOTH THE ECMWF AND THE GFS DO SUPPORT A LARGE UPPER LEVEL CLOSED LOW PUSHING SOUTH FROM NW CANADA TO CENTRAL CANADA BY LATE IN THE WEEKEND. THIS ENERGY WILL TRANSLATE TO THE SURFACE WITH A STRONG LOW PRESSURE SYSTEM DEVELOPING ACROSS SOUTHCENTRAL CANADA...PULLING A STRONG FRONTAL BOUNDARY WHICH WILL SWEEP ACROSS MUCH OF THE CENTRAL AND EVENTUALLY EASTERN CONUS. EXACT TIMING IS STILL OBVIOUSLY IN LOW CONFIDENCE...BUT IF THIS PANS OUT ANOTHER GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS WILL IMPACT THE REGION AHEAD OF THE FRONTAL ZONE AS WE END THE EXTENDED PERIOD MONDAY. WITH A NW FLOW REGIME...COOLER AIR WILL BE PULLED IN FROM CANADA TO START OUT THE EXTENDED PERIOD. THEN AS THE TROUGH BACK-BUILDS AND GENERALLY SW FLOW TAKES HOLD DURING A PORTION OF THE PERIOD...WE WILL ACTUALLY CONTINUE TO PULL COOLER AIR IN FROM THE NORTH...AS WINDS BECOME MORE NW JUST TO OUR WEST. THIS...IN CONJUNCTION WITH CLOUD COVER AND POTENTIAL RAIN...WILL KEEP TEMPERATURES MODERATED THROUGH MUCH OF THE EXTENDED...AT LEAST INTO THE WEEKEND. EXPECT HIGHS IN THE UPPER 70S TO LOW 80S. BY MONDAY...ENERGY WILL BE REDIRECTED TOWARDS THE INCOMING UPPER LEVEL HIGH...CAUSING A BREAK IN THE UPPER LEVEL WIND FLOW ACROSS THE REGION. THIS WILL ALLOW FOR A BETTER PULL OF TRUE SW WIND FLOW IN THE MID AND LOW LEVELS...WHICH COMBINED WITH ANY SUNSHINE...WILL BOOST TEMPS BACK UP INTO THE MID AND MAYBE EVEN UPPER 80S FOR THE DAY. WITH PARTLY TO MOSTLY CLOUDY SKIES EXPECTED TO STICK AROUND DURING THE NIGHT...EXPECT TEMPERATURES TO REMAIN MODERATED AS WELL...STAYING AROUND THE MID AND UPPER 60S FOR EARLY MORNING LOWS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 745 AM EDT MON JUN 29 2015 IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE BULK OF THE FORECAST PERIOD. A BAND OF SCATTERED SHOWERS...WITH A FEW EMBEDDED THUNDERSTORMS ASSOCIATED WITH AN APPROACHING COLD FRONTAL SYSTEM WILL CONTINUE TO OVERSPREAD THE REGION FROM WEST TO EAST THIS MORNING. SCATTERED THUNDERSTORMS ARE THEN EXPECTED TO REDEVELOP DURING THE AFTERNOON...LINGERING INTO THE EARLY EVENING AS ANOTHER DISTURBANCE PASSES THROUGH THE AREA. THE PRECIPITATION MAY BRING TEMPORARY LOCALIZED IFR CONDITIONS...ESPECIALLY IN AFTERNOON THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY CONTAIN MARGINALLY LARGE HAIL AND STRONG WINDS. OTHERWISE...LIGHT SOUTHERLY WINDS WILL GRADUALLY VEER TO THE SOUTHWEST AND INCREASE TO AROUND 10 KTS...WITH HIGHER GUSTS TO AROUND 20 KTS IN THE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...JMW AVIATION...RAY
AREA FORECAST DISCUSSION
NWS JACKSON KY
745 AM EDT MON JUN 29 2015 .UPDATE... ISSUED AT 745 AM EDT MON JUN 29 2015 FORECAST WAS NOT IN TOO BAD OF SHAPE. BROUGHT GRIDS IN LINE WITH LATEST RADAR TRENDS AND HOURLY OBS. SOUTHERN END OF BAND OF SHOWERS IS STRUGGLING TO HOLD TOGETHER...BUT THERE HAS BEEN SOME REDEVELOPMENT OVER THE PAST HOUR. BASED ON RADAR MOSAIC...HIGHEST POPS IN THE NORTH AND ESPECIALLY I-64 CORRIDOR LOOKS RIGHT ON TARGET FOR THE START OF THE MORNING. WITH ADDITIONAL SHORTWAVE ENERGY DROPPING INTO THE BASE OF OUR OVERHEAD TROUGH...STILL EXPECTING REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON...LINGERING INTO THE EARLY EVENING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 417 AM EDT MON JUN 29 2015 HIGH AMPLITUDE PATTERN ALOFT WILL MEAN EASTERN CONUS TROUGH WILL DOMINATE OUR WEATHER THROUGH THE SHORT TERM. BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SFC FRONTAL SYSTEM CONTINUES TO MOVE EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. MODELS...AND ESPECIALLY THE HRRR SUGGEST THAT THIS ACTIVITY WILL GRADUALLY WEAKEN AS IT MOVES INTO OUR AREA AROUND DAWN...DUE TO UPPER LEVEL SUPPORT SHEARING OUT. HOWEVER...ADDITIONAL SHORTWAVE ENERGY ALOFT ROUNDING THE BASE OF AN EASTERN CONUS TROUGH SHOULD HELP REGENERATE ACTIVITY THROUGH THE AFTERNOON. SHEAR AND INSTABILITY APPEAR SUFFICIENT FOR THE THREAT OF SOME STRONG TO SEVERE THUNDERSTORMS...MAINLY THROUGH THE AFTERNOON AND EARLY EVENING. BUT THERE ARE SOME LIMITING FACTORS FOR EXAMPLE... CLOUD COVER...LESS THAN IMPRESSIVE MID LEVEL LAPSE RATES...AND FORCING...THE STRONGEST OF WHICH MAY REMAIN FURTHER NORTH AND WEST OF OUR AREA. THEREFORE SEVERE THREAT MAY BE MORE ISOLD IN NATURE WITH RESPECT TO COVERAGE. JUST THE SAME WITH SPC PLACING OUR AREA IN A SLIGHT RISK TODAY WILL CONTINUE TO ADVERTISE THE POTENTIAL. WITH THE APPROACH OF THE SFC TROUGH TO OUR WEST AND MID LEVEL CLOUD COVER CURRENTLY MOVING INTO OUR AREA EXPECT TEMPERATURES TO BEGIN TO REBOUND ACROSS MUCH OF THE AREA BETWEEN NOW AND SUNRISE. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 351 AM EDT MON JUN 29 2015 UPPER LEVEL MODELS CONTINUE TO SUPPORT A LONGWAVE TROUGH ACROSS MUCH OF THE EASTERN CONUS TO START OFF THE PERIOD...KEEPING THE OHIO RIVER VALLEY IN NW FLOW REGIME FROM TUESDAY NIGHT THROUGH FRIDAY. THE AXIS OF THE TROUGH WILL THEN SHIFT DIRECTLY OVER KY AS ANOTHER SHORTWAVE DIGS SOUTHWARD FROM CANADA TO START OFF THE WEEKEND. FINALLY...THE UPPER LEVEL LONGWAVE PATTERN WILL SLOWLY DAMPEN AS WE HEAD INTO THE END OF THE EXTENDED PERIOD SUNDAY INTO MONDAY. HOWEVER...BY THE WEEKEND MODELS SHOW QUITE A BIT OF DISCONTINUITY...SO THE EXACT TIMING AND MAGNITUDE OF THE UPPER LEVEL TROUGH WILL BE SOMEWHAT LOW CONFIDENCE. WITH THE GENERAL NW FLOW...EXPECT SHORTWAVES TO CONTINUE TO TRAVEL SE AND INTO THE OHIO RIVER VALLEY. THIS WILL RESULT IN SEVERAL SURFACE LOW PRESSURE CENTERS AND FRONTAL BOUNDARIES PASSING THROUGH THE REGION...CREATING THE ENERGY AND LIFT TO PRODUCE SHOWERS AND THUNDERSTORMS. AS HAS BEEN THE CASE OVER THE LAST FEW WEEKS...EXPECT MOST WIDESPREAD ACTIVITY TO BE RIGHT ALONG AND JUST AHEAD OF THE FRONTAL BOUNDARY...PEAKING IN SEVERITY DURING THE AFTERNOON AND EARLY EVENING HOURS IN CONJUNCTION WITH THE PEAK HEATING. THE FIRST OF THESE BOUNDARIES WILL BE EXITING TUESDAY NIGHT AS THE NEXT BOUNDARY TO OUR NORTH MAKES A SHIFT SOUTHWARD. THIS SECOND BOUNDARY IS EXPECTED TO MAKE IT INTO THE REGION WEDNESDAY NIGHT...AND ACCORDING TO THE LATEST 00Z RUN OF THE GFS40...SHOULD BECOME STALLED OUT ACROSS THE REGION THROUGH THE DAY FRIDAY AS THE UPPER LEVEL TROUGH BACK-BUILDS ACROSS THE OHIO RIVER VALLEY. ALONG THIS BOUNDARY...EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...WITH ANY UPPER LEVEL WAVES OF ENERGY ENHANCING CHANCES FOR A MCS TO PASS THROUGH THE REGION. THE FRONTAL BOUNDARY WILL FINALLY SHIFT SE OF THE STATE BY FRIDAY EVENING...ASSUMING MODEL TIMING PANS OUT. UNFORTUNATELY...ANOTHER WEAK FRONTAL BOUNDARY WILL HAVE FORMED TO OUR NORTH...AND WE WILL STILL BE IN VERY CLOSE PROXIMITY TO THE EXITING FRONT. UNDER SW FLOW BY THIS POINT...AND STILL IN AN UPPER LEVEL LOW PRESSURE TROUGHING PATTERN...EXPECT LESS ORGANIZED SCATTERED CONVECTION TO CONTINUE INTO THE WEEKEND...WITH BEST CHANCES STILL EXPECTED OVER THE SE CWA CLOSER TO THE EXITING FRONT. BY SUNDAY...MODEL CONFIDENCE IN CONVECTION STARTS TO DECLINE AS THERE IS LITTLE AGREEMENT IN THE PATTERN ALOFT. IF THE GFS IS CORRECT...THE UPPER LEVEL TROUGH WILL BEGIN DAMPENING/WEAKENING... BUT CONTINUED WARM SW FLOW AND A PASSING SHORTWAVE COULD BE THE SPARK FOR YET MORE SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON/EVENING HOURS. BOTH THE ECMWF AND THE GFS DO SUPPORT A LARGE UPPER LEVEL CLOSED LOW PUSHING SOUTH FROM NW CANADA TO CENTRAL CANADA BY LATE IN THE WEEKEND. THIS ENERGY WILL TRANSLATE TO THE SURFACE WITH A STRONG LOW PRESSURE SYSTEM DEVELOPING ACROSS SOUTHCENTRAL CANADA...PULLING A STRONG FRONTAL BOUNDARY WHICH WILL SWEEP ACROSS MUCH OF THE CENTRAL AND EVENTUALLY EASTERN CONUS. EXACT TIMING IS STILL OBVIOUSLY IN LOW CONFIDENCE...BUT IF THIS PANS OUT ANOTHER GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS WILL IMPACT THE REGION AHEAD OF THE FRONTAL ZONE AS WE END THE EXTENDED PERIOD MONDAY. WITH A NW FLOW REGIME...COOLER AIR WILL BE PULLED IN FROM CANADA TO START OUT THE EXTENDED PERIOD. THEN AS THE TROUGH BACK-BUILDS AND GENERALLY SW FLOW TAKES HOLD DURING A PORTION OF THE PERIOD...WE WILL ACTUALLY CONTINUE TO PULL COOLER AIR IN FROM THE NORTH...AS WINDS BECOME MORE NW JUST TO OUR WEST. THIS...IN CONJUNCTION WITH CLOUD COVER AND POTENTIAL RAIN...WILL KEEP TEMPERATURES MODERATED THROUGH MUCH OF THE EXTENDED...AT LEAST INTO THE WEEKEND. EXPECT HIGHS IN THE UPPER 70S TO LOW 80S. BY MONDAY...ENERGY WILL BE REDIRECTED TOWARDS THE INCOMING UPPER LEVEL HIGH...CAUSING A BREAK IN THE UPPER LEVEL WIND FLOW ACROSS THE REGION. THIS WILL ALLOW FOR A BETTER PULL OF TRUE SW WIND FLOW IN THE MID AND LOW LEVELS...WHICH COMBINED WITH ANY SUNSHINE...WILL BOOST TEMPS BACK UP INTO THE MID AND MAYBE EVEN UPPER 80S FOR THE DAY. WITH PARTLY TO MOSTLY CLOUDY SKIES EXPECTED TO STICK AROUND DURING THE NIGHT...EXPECT TEMPERATURES TO REMAIN MODERATED AS WELL...STAYING AROUND THE MID AND UPPER 60S FOR EARLY MORNING LOWS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 745 AM EDT MON JUN 29 2015 IN GENERAL EXPECTING VFR CONDITIONS THROUGH THE BULK OF THE FORECAST PERIOD. A BAND OF SCATTERED SHOWERS...WITH A FEW EMBEDDED THUNDERSTORMS ASSOCIATED WITH AN APPROACHING COLD FRONTAL SYSTEM WILL CONTINUE TO OVERSPREAD THE REGION FROM WEST TO EAST THIS MORNING. SCATTERED THUNDERSTORMS ARE THEN EXPECTED TO REDEVELOP DURING THE AFTERNOON...LINGERING INTO THE EARLY EVENING AS ANOTHER DISTURBANCE PASSES THROUGH THE AREA. THE PRECIPITATION MAY BRING TEMPORARY LOCALIZED IFR CONDITIONS...ESPECIALLY IN AFTERNOON THUNDERSTORMS. SOME OF THE THUNDERSTORMS MAY CONTAIN MARGINALLY LARGE HAIL AND STRONG WINDS. OTHERWISE...LIGHT SOUTHERLY WINDS WILL GRADUALLY VEER TO THE SOUTHWEST AND INCREASE TO AROUND 10 KTS...WITH HIGHER GUSTS TO AROUND 20 KTS IN THE AFTERNOON. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...RAY LONG TERM...JMW AVIATION...RAY
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
956 AM EDT MON JUN 29 2015 .SYNOPSIS... WARMER AND DRIER TODAY BEFORE ANOTHER ROUND OF RAIN MOVES IN THIS EVENING AND OVERNIGHT. && .NEAR TERM /THROUGH TONIGHT/... MID-MORNING UPDATE TWEAKING POPS AND SKY COVER TO RECENT RADAR AND SATELLITE TRENDS RESPECTIVELY. SKY WAS TRIMMED BACK CONSIDERABLY THROUGH THE EARLY AFTERNOON AS THE WARM FRONT AND ASSOCIATED PRECIPITATION/CLOUDS MOVE ALONG OUR NORTHERN PERIPHERY INTO NORTHEAST OHIO AND NORTHWEST PENNSYLVANIA. INGESTING THE RAW HRRR TEMPERATURES SHOWED TOO MUCH OF A GRADIENT BETWEEN THE MOSTLY SUNNY CONDITIONS OVER THE SOUTHERN 1/3 OF THE FORECAST AREA AND THE COOLER NORTH WHERE THE CLOUDS AND RAIN ARE EXPECTED TO TRACK THROUGH MID-AFTERNOON. THE HRRRS HOURLY TEMPERATURE EVOLUTION WAS...HOWEVER...QUITE PLAUSIBLE SO A BLEND OF PREVIOUS FORECAST WAS MADE WITH THE TEMPERED HRRR NUMBERS FOR HIGHS TODAY. MAY NEED TO RE-ADJUST SOME HIGHS ACROSS NORTHERN WV LATER AS THE LATEST UPDATE MAY HAVE NOT GONE HIGH ENOUGH. HOLDING BACK POPS A LITTLE LONGER ACROSS SOUTHWEST PENNSYLVANIA AS THE DIGGING LOW WILL TAKE SOME TIME TO ADVANCE EASTWARD. STILL UNIMPRESSED WITH CAPE NUMBERS PROGGED OFF THE NAM AND RAP ANALYSIS...SO WILL CONTINUE TO LIMIT THUNDERSTORM POTENTIAL TO JUST ISOLATED. HAVE CONTINUED LIKELY POPS DURING THE OVERNIGHT HOURS...WITH HIGHEST POPS NORTHWEST OF PITTSBURGH FOLLOWING THE TRACK OF THE LOW CENTER OVER LAKE ERIE. NOT MUCH INSTABILITY FOR THUNDERSTORMS TO WORK WITH...ESPECIALLY CONSIDERING THE WARM FRONT WILL CROSS THE REGION OVERNIGHT. THIS SHOULD CONTINUE TO LIMIT SEVERE WEATHER POTENTIAL. SOUTHERLY WINDS WILL RAISE DAYTIME HIGHS SOME 10 DEGREES FROM SUNDAYS HIGH TEMPERATURES...ALTHOUGH THIS WILL REMAIN BELOW NORMAL. OVERNIGHT TEMPERATURES WILL BE CLOSE TO NORMAL AS WARM ADVECTION WILL CONTINUE. TAX/TG && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... BROAD UPPER TROUGH WILL REMAIN ACROSS THE EASTERN UNITED STATES TUESDAY AND WEDNESDAY. SCATTERED THUNDERSTORMS WILL CONTINUE THROUGH THE PERIOD...ESPECIALLY ACROSS SOUTHERN COUNTIES TUESDAY AFTERNOON. THERE WILL BE LITTLE CHANGE IN THE OVERALL TEMPERATURE PATTERN...KEEPING DAYTIME HIGHS SLIGHTLY BELOW NORMAL AND OVERNIGHT LOWS AROUND NORMAL. && .LONG TERM /THURSDAY THROUGH SUNDAY/... UNSETTLED WEATHER WILL CONTINUE THROUGH THE EXTENDED AS THERE IS MINIMAL CHANGE EXPECTED TO THE LONGWAVE PATTERN AND TROUGHING REMAINS THE DOMINANT FEATURE. LATEST MODEL CONSENSUS IS IN FAIRLY GOOD AGREEMENT WITH THIS...HOWEVER AGREEMENT AND CONTINUITY IN ANY FINER DETAILS IS LACKING SO THE FORECAST CONTINUES TO BE FAIRLY BROAD BRUSHED. AT THIS TIME THE HIGHEST PROBABILITY OF SEEING SHOWERS AND STORMS LOOKS TO BE THURSDAY WHEN UPPER LEVEL DYNAMICS ARE FAVORABLE AND SATURDAY WHEN A SHORTWAVE IS PROGGED TO CROSS THE REGION. TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...WITH A WARMING TREND TOWARDS THE END OF THE PERIOD AS THE LONGWAVE PATTERN BECOMES MORE ZONAL. && .AVIATION /14Z MONDAY THROUGH FRIDAY/... VFR MID LEVEL CLOUDS ARE EXPECTED TO INCREASE THIS MORNING AS A WARM FRONT APPROACHES...WITH A CHANCE OF SHOWERS LATE THIS MORNING POSSIBLE OUT AHEAD OF THE FRONT. THESE SHOULD BE LIGHT AND DO NOT ANTICIPATE MCU IMPACT TO CIGS/VIS. LATER TODAY MORE SUBSTANTIAL PRECIPITATION WILL DEVELOP AS THE WARM FRONT APPROACHES BUT LATEST MODEL SOUNDINGS STILL INDICATE CLOUD LEVELS WILL NOT DROP TO AOB 3KFT. THUNDERSTORMS WILL BE POSSIBLE LATE THIS AFTERNOON BUT THIS ALL DEPENDS ON HOW MUCH INSTABILITY IS REALIZED IN LOWER LEVELS. AT THIS POINT THE THREAT OF ANY SEVERE WEATHER LOOKS TO REMAIN SOUTHWEST OF THE AREA...AND ANY ACTIVITY LATER TONIGHT ALONG THE FRONT SHOULD BE LIMITED. .OUTLOOK.../TUESDAY THROUGH FRIDAY/... PERIODIC RESTRICTIONS ARE POSSIBLE THROUGH THE WEEK WITH A SERIES OF CROSSING DISTURBANCES. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
829 AM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 826 AM CDT MON JUN 29 2015 CLOUD SHIELD EXTENDING ACROSS THE NORTH CENTRAL IS FROM THE SMOKE DEBRIS THAT IS BEING CARRIED DOWNSTREAM FROM THE ALASKA REGION. GRIDS TODAY AND THIS EVENING UPDATED FOR SKY CONDITIONS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 332 AM CDT MON JUN 29 2015 TODAY AND TONIGHT...WINDS AT 850 MB TO 750 MB ARE SOUTH ACROSS THE CNTL HIGH PLAINS THIS MORNING AND A DISTURBANCE IS DROPPING SOUTH VERY QUICKLY IN THE NORTHWEST FLOW. STORMS ARE UNDERWAY FROM SPEARFISH SD TO CHEYENNE WY AND THE HRRR...RAP...ARW...NMM AND NAM CARRY THIS ACTIVITY INTO THE PANHANDLE AND SWRN NEB FOR A FEW HOURS THIS MORNING. SATELLITE TIMING TOOLS INDICATE THE DISTURBANCE NORTH OF THE BLACK HILLS WOULD CLEAR SWRN NEB 13Z-14Z THIS MORNING. THE ARW AND NMM MODELS SUGGEST A SMALL DISTURBANCE ON SATELLITE ACROSS SERN SASKATCHEWAN THIS MORNING COULD SPAWN ISOLATED SHOWERS AND TSTMS THIS AFTN ACROSS NCNTL NEB. THIS FEATURE IS UNDER REVIEW GIVEN THE LIMITED RADAR COVERAGE ACROSS ND AND THE LACK OF LOW LEVEL CONVERGENCE SHOWN THE MODEL CONSENSUS. THE NAM SHOWS SOUTH WINDS DEVELOPING TONIGHT BELOW 750 MB ACROSS SWRN NEB AND THIS COULD PROVIDE AN OPPORTUNITY FOR MORE CONVECTIVE DEVELOPMENT. IN FACT...SOUTH WINDS SHOULD CONTINUE TODAY ACROSS THE CNTL HIGH PLAINS ALONG HWY 385 AIMED AT THE BLACK HILLS WHICH COULD CAUSE STORMS TO FIRE ON THE BLACK HILLS THIS AFTN. THE MODEL PREDICTABILITY OF THE ONGOING CONVECTION WOULD APPEAR LOW GIVEN THAT THE RAP AND NAM SHOW NO ELEVATED INSTABILITY ACROSS THE PANHANDLE. THUS FORECAST RAIN CHANCES THIS AFTN AND TONIGHT ARE UNCERTAIN. OTHERWISE...MIXING HEIGHTS RISE TO 700 MB TODAY ALLOWING FOR A BUMP IN TEMPERATURES. HIGHS IN THE LOWER 90S SHOULD BE WIDESPREAD WITH NEARLY CLEAR SKIES. DEW POINTS IN THE 50S TO AROUND 60 SHOULD CONTINUE TODAY AND TONIGHT ALLOWING FOR ONE MORE RADIATION NIGHT WITH LOWS IN THE UPPER 50S TO LOWER 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON JUN 29 2015 SYNOPTIC PATTERN REMAINS HIGHLY AMPLIFIED THROUGH THE MIDDLE OF THE WEEK WITH ANTICYCLONIC FLOW CENTERED OVER THE GREAT BASIN...AND A TROUGH TO THE EAST CENTERED OVER THE GREAT LAKES REGION. THIS LEAVES THE CWA IN PERSISTENT NORTHWEST FLOW ALOFT. A SERIES OF SHORTWAVE TROUGHS WILL ATTEMPT TO FLATTEN THE WESTERN CONUS RIDGE AS THEY TRAVERSE TROUGH SOUTHERN CANADA. THE FIRST SHORTWAVE APPROACHES THE CWA ON TUESDAY. LOW LEVEL SOUTHWESTERLY FLOW WILL PUSH H85 TEMPS ABOVE 30C IN SOUTHWEST NEBRASKA. LATEST GUIDANCE HAS TRENDED WARMER FOR HIGH TEMPS ON TUESDAY...WITH THE MAV NOW NEARING 100 FOR PARTS OF THE AREA. HOWEVER...MODELS CONTINUE TO SHOW A CIRRUS SHIELD SPREADING OVER THE CENTRAL PLAINS AS A SURGE OF MOISTURE AOA 500MB ROUNDS THE TOP OF THE WESTERN CONUS RIDGE. STILL TRENDED HIGHS UP A DEGREE OR TWO...BUT KEPT A CONSERVATIVE APPROACH GIVEN POTENTIAL CLOUD COVER. A WEAK COLD FRONT MOVES THROUGH TUESDAY EVENING AND NIGHT AS THE SHORTWAVE PASSES ALOFT. ISOLATED STORMS WILL BE POSSIBLE ALONG AND BEHIND FRONT TUESDAY NIGHT. SHEAR WILL BE STRONG ENOUGH TO SUPPORT A FEW STRONG STORMS...BUT MODEL BUFR SOUNDINGS SHOW THAT ANY ACTIVITY WILL BE HIGHLY ELEVATED DUE TO DRY LOW LEVELS SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. BEST CHANCES FOR STORMS WILL LIKELY REMAIN JUST EAST OF THE CWA WHERE THE LLJ WILL BE FOCUSED AND BETTER MOISTURE RESIDES. TEMPERATURES WILL BE A FEW DEGREES COOLER WEDNESDAY BUT STILL RANGE FOR THE MID 80S TO LOW 90S. ISOLATED TO SCATTERED STORM CHANCES ENTER THE FORECAST ONCE AGAIN WEDNESDAY NIGHT AND THURSDAY AS THE NEXT UPPER LEVEL SHORTWAVE APPROACHES FROM THE NORTHWEST. MODELS REMAIN IN FAIR AGREEMENT THROUGH THE END OF THE WEEK AS A RIDGE ALOFT BUILDS OVER THE CENTRAL CONUS TO END THE WEEK WITH DRY CONDITIONS EXPECTED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 615 AM CDT MON JUN 29 2015 UPPER LEVEL DISTURBANCES ACROSS THE NRN HIGH PLAINS WILL MOVE SOUTH TODAY AND TONIGHT...PERHAPS PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS ACROSS WRN NEB ALONG AND WEST OF HIGHWAY 61. A DISTURBANCE ACROSS THE BLACK HILLS IS UNDERWAY ATTM AND A SECOND MAY BE POSITIONED ACROSS MT THIS MORNING WHICH AFFECT THE WEST THIS AFTN AND THIS EVENING. OTHERWISE VFR IS EXPECTED ALL AREAS. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KECK SHORT TERM...CDC LONG TERM...MARTIN AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
616 AM CDT MON JUN 29 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 332 AM CDT MON JUN 29 2015 TODAY AND TONIGHT...WINDS AT 850 MB TO 750 MB ARE SOUTH ACROSS THE CNTL HIGH PLAINS THIS MORNING AND A DISTURBANCE IS DROPPING SOUTH VERY QUICKLY IN THE NORTHWEST FLOW. STORMS ARE UNDERWAY FROM SPEARFISH SD TO CHEYENNE WY AND THE HRRR...RAP...ARW...NMM AND NAM CARRY THIS ACTIVITY INTO THE PANHANDLE AND SWRN NEB FOR A FEW HOURS THIS MORNING. SATELLITE TIMING TOOLS INDICATE THE DISTURBANCE NORTH OF THE BLACK HILLS WOULD CLEAR SWRN NEB 13Z-14Z THIS MORNING. THE ARW AND NMM MODELS SUGGEST A SMALL DISTURBANCE ON SATELLITE ACROSS SERN SASKATCHEWAN THIS MORNING COULD SPAWN ISOLATED SHOWERS AND TSTMS THIS AFTN ACROSS NCNTL NEB. THIS FEATURE IS UNDER REVIEW GIVEN THE LIMITED RADAR COVERAGE ACROSS ND AND THE LACK OF LOW LEVEL CONVERGENCE SHOWN THE MODEL CONSENSUS. THE NAM SHOWS SOUTH WINDS DEVELOPING TONIGHT BELOW 750 MB ACROSS SWRN NEB AND THIS COULD PROVIDE AN OPPORTUNITY FOR MORE CONVECTIVE DEVELOPMENT. IN FACT...SOUTH WINDS SHOULD CONTINUE TODAY ACROSS THE CNTL HIGH PLAINS ALONG HWY 385 AIMED AT THE BLACK HILLS WHICH COULD CAUSE STORMS TO FIRE ON THE BLACK HILLS THIS AFTN. THE MODEL PREDICTABILITY OF THE ONGOING CONVECTION WOULD APPEAR LOW GIVEN THAT THE RAP AND NAM SHOW NO ELEVATED INSTABILITY ACROSS THE PANHANDLE. THUS FORECAST RAIN CHANCES THIS AFTN AND TONIGHT ARE UNCERTAIN. OTHERWISE...MIXING HEIGHTS RISE TO 700 MB TODAY ALLOWING FOR A BUMP IN TEMPERATURES. HIGHS IN THE LOWER 90S SHOULD BE WIDESPREAD WITH NEARLY CLEAR SKIES. DEW POINTS IN THE 50S TO AROUND 60 SHOULD CONTINUE TODAY AND TONIGHT ALLOWING FOR ONE MORE RADIATION NIGHT WITH LOWS IN THE UPPER 50S TO LOWER 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON JUN 29 2015 SYNOPTIC PATTERN REMAINS HIGHLY AMPLIFIED THROUGH THE MIDDLE OF THE WEEK WITH ANTICYCLONIC FLOW CENTERED OVER THE GREAT BASIN...AND A TROUGH TO THE EAST CENTERED OVER THE GREAT LAKES REGION. THIS LEAVES THE CWA IN PERSISTENT NORTHWEST FLOW ALOFT. A SERIES OF SHORTWAVE TROUGHS WILL ATTEMPT TO FLATTEN THE WESTERN CONUS RIDGE AS THEY TRAVERSE TROUGH SOUTHERN CANADA. THE FIRST SHORTWAVE APPROACHES THE CWA ON TUESDAY. LOW LEVEL SOUTHWESTERLY FLOW WILL PUSH H85 TEMPS ABOVE 30C IN SOUTHWEST NEBRASKA. LATEST GUIDANCE HAS TRENDED WARMER FOR HIGH TEMPS ON TUESDAY...WITH THE MAV NOW NEARING 100 FOR PARTS OF THE AREA. HOWEVER...MODELS CONTINUE TO SHOW A CIRRUS SHIELD SPREADING OVER THE CENTRAL PLAINS AS A SURGE OF MOISTURE AOA 500MB ROUNDS THE TOP OF THE WESTERN CONUS RIDGE. STILL TRENDED HIGHS UP A DEGREE OR TWO...BUT KEPT A CONSERVATIVE APPROACH GIVEN POTENTIAL CLOUD COVER. A WEAK COLD FRONT MOVES THROUGH TUESDAY EVENING AND NIGHT AS THE SHORTWAVE PASSES ALOFT. ISOLATED STORMS WILL BE POSSIBLE ALONG AND BEHIND FRONT TUESDAY NIGHT. SHEAR WILL BE STRONG ENOUGH TO SUPPORT A FEW STRONG STORMS...BUT MODEL BUFR SOUNDINGS SHOW THAT ANY ACTIVITY WILL BE HIGHLY ELEVATED DUE TO DRY LOW LEVELS SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. BEST CHANCES FOR STORMS WILL LIKELY REMAIN JUST EAST OF THE CWA WHERE THE LLJ WILL BE FOCUSED AND BETTER MOISTURE RESIDES. TEMPERATURES WILL BE A FEW DEGREES COOLER WEDNESDAY BUT STILL RANGE FOR THE MID 80S TO LOW 90S. ISOLATED TO SCATTERED STORM CHANCES ENTER THE FORECAST ONCE AGAIN WEDNESDAY NIGHT AND THURSDAY AS THE NEXT UPPER LEVEL SHORTWAVE APPROACHES FROM THE NORTHWEST. MODELS REMAIN IN FAIR AGREEMENT THROUGH THE END OF THE WEEK AS A RIDGE ALOFT BUILDS OVER THE CENTRAL CONUS TO END THE WEEK WITH DRY CONDITIONS EXPECTED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 615 AM CDT MON JUN 29 2015 UPPER LEVEL DISTURBANCES ACROSS THE NRN HIGH PLAINS WILL MOVE SOUTH TODAY AND TONIGHT...PERHAPS PRODUCING ISOLATED SHOWERS AND THUNDERSTORMS ACROSS WRN NEB ALONG AND WEST OF HIGHWAY 61. A DISTURBANCE ACROSS THE BLACK HILLS IS UNDERWAY ATTM AND A SECOND MAY BE POSITIONED ACROSS MT THIS MORNING WHICH AFFECT THE WEST THIS AFTN AND THIS EVENING. OTHERWISE VFR IS EXPECTED ALL AREAS. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...MARTIN AVIATION...CDC
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
923 AM EDT MON JUN 29 2015 .SYNOPSIS... A STATIONARY FRONT WILL DISSIPATE ACROSS THE AREA THIS AFTERNOON. BERMUDA HIGH PRESSURE WILL REDEVELOP TUESDAY AND PERSIST INTO THE UPCOMING WEEKEND BRINGING ABOVE NORMAL TEMPERATURES AND TYPICAL AFTERNOON AND EVENING THUNDERSTORM CHANCES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 915 AM MONDAY...THE MORNING CONVECTION ALONG THE COAST AND OVER PORTIONS OF BRUNSWICK COUNTY HAS SHIFTED 40 MILES OFF THE COAST. THE STALLED FRONTAL BOUNDARY IS DEPICTED VERY WELL BY THE DEWPOINT FIELD. THE BOUNDARY IS NEAR A LINE FROM JACKSONVILLE TO WESTERN COLUMBUS COUNTY TO KINGSTREE. THE 12 UTC RUN OF THE HRRR IS SHOWING THE HIGHER DEWPOINTS BEING SHUNTED TO THE COAST WITH THE DEWPOINTS ALONG THE COAST REMAINING HIGHER. THE HRRR IS SHOWING THE MOISTURE ADVECTING BACK INTO THE AREA AFTER 3 PM AND INTO THE OVERNIGHT. THERE IS A SMALL CHANCE OF A THUNDERSTORM IN THE AREA OF THE HIGHER DEWPOINTS ALONG THE COAST THIS AFTERNOON AND THE HRRR IS ONLY SHOWING WEAK REFLECTIVITY SIGNATURES OVER SOUTHEAST NORTH CAROLINA AND HORRY COUNTY THIS AFTERNOON. SO WILL KEEP AN ISOLATED STORM MENTION IN THESE AREA FOR THE AFTERNOON. HIGHS TODAY SHOULD REACH THE UPPER 80S TO LOWER 90S WITH MINS TONIGHT IN THE UPPER 60S TO LOWER 70S. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...HOT AND DRY FOR TUESDAY...BUT A RETURN TO MORE TYPICAL SUMMERTIME WEATHER WILL DEVELOP WEDNESDAY AS THE CALENDAR FLIPS TO JULY. BROAD MID-LEVEL TROUGH REMAINS ACROSS THE CONUS THROUGH MID- WEEK...BUT WITH ITS RIDGE AXIS STAYING WEST OF THE AREA...SW FLOW WILL HELP DRIVE TEMPS TO ABOVE NORMAL EVEN WITH SOME RELATIVELY LOWERED THICKNESSES. TEMPS TUESDAY WILL WARM WELL INTO THE 90S...WITH HIGHS WEDNESDAY A FEW DEGREES COOLER...BUT STILL LIKELY ABOVE CLIMO FOR THIS TIME OF YEAR. HUMIDITY WILL ALSO BEGIN TO RAMP BACK UP...ESPECIALLY WEDNESDAY...AS RETURN FLOW PUSHES ATLANTIC MOISTURE BACK INTO THE COLUMN. WHILE TUESDAY LOOKS DRY...LATE TUESDAY NIGHT A SHORTWAVE WILL ROTATE AROUND THE BASE OF THE TROUGH AND UP THROUGH THE CENTRAL CAROLINAS. THIS MAY PROVIDE ENOUGH FORCING FOR SOME LOW-END POP ACROSS WESTERN ZONES TUESDAY NIGHT. BETTER CONVECTIVE CHANCES EXIST WEDNESDAY AS PWATS RISE BACK ABOVE 1.5 INCHES AND THE TROUGH FLATTENS - ACTUALLY DRIVING SLIGHTLY LOWER THICKNESSES ACROSS THE EASTERN CAROLINAS. DO NOT ANTICIPATE WIDESPREAD SHOWERS/TSTMS...BUT THE SEA BREEZE AND PIEDMONT TROUGH MAY BOTH BE ACTIVE ON WEDNESDAY. MINS BOTH NIGHTS WILL BE WELL ABOVE SEASONABLE NORMS...WITH WIDESPREAD MID 70S EXPECTED...AND SOME UPR 70S ON THE IMMEDIATE COAST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY...FAIRLY TYPICAL JULY WEATHER WILL OCCUR THROUGH THE PERIOD...AND A DECENT JULY 4TH WEEKEND APPEARS TO BE SHAPING UP LOCALLY. BERMUDA HIGH PRESSURE WILL REMAIN WELL OFFSHORE BUT MAINTAIN RIDGING BACK TOWARDS THE EAST COAST. ALOFT...A BROAD TROUGH WILL FLATTEN LATE IN THE WEEK BEFORE SHARPENING ONCE AGAIN DURING THE UPCOMING WEEKEND. THE TROUGH AXIS IS PROGGED TO REMAIN WEST OF THE CAROLINAS HOWEVER...SO THIS WILL ACTUALLY DRIVE INCREASING THICKNESSES LOCALLY. THE COMBINATION OF THESE FEATURES WILL PUSH TEMPS INTO THE 90S...A FEW DEGREES ABOVE CLIMO...EACH AFTN...AND POSSIBLE WELL ABOVE CLIMO BY THE WEEKEND. MINS WILL ALSO BE WELL ABOVE NORMAL...MID 70S TO AROUND 80 EACH NIGHT THANKS TO THE CONTINUOUS WARM SW FLOW. TSTM CHANCES WILL EXIST EACH AFTN ALONG THE TYPICAL BOUNDARIES...AND AIDED BY THE SUBTLY LOWERED HEIGHTS ALOFT. BY THE WEEKEND...CONVECTION WILL DECREASE AS THE HEIGHTS BUILD OVERHEAD. WHILE IT IS TOO EARLY TO FOCUS ON DETAILS OF WHERE THE BEST POP WILL EXIST...THU/FRI WILL FEATURE BETTER CONVECTIVE CHANCES THAN EITHER SAT OR SUN. && .AVIATION /13Z MONDAY THROUGH FRIDAY/... AS OF 12Z...THE FOG AT LBT SHOULD BE OUT OF HERE IN AN HOUR OR TWO. FRONTAL BOUNDARY OFFSHORE WILL KEEP THE CONVECTION OFFSHORE AS WELL. WINDS WILL BE VARIABLE THIS MORNING...NORTHEAST AT TIMES...BECOMING SOUTHEASTERLY WITH THE RESULTANT THIS AFTERNOON. LOW PRESSURE BEGINS TO APPROACH THE CWA FROM THE WEST TONIGHT...WITH SOUTHWEST FLOW RETURNING. EXTENDED OUTLOOK...PREDOMINATELY VFR THROUGH TUESDAY. POSSIBLE AFTERNOON SHOWERS AND STORMS WEDNESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 915 AM MONDAY...WEST TO SW WINDS OF 10 TO 15 KT THROUGH THE PERIOD WITH SEAS OF 2 TO 4 FT. ISOLATED TO SCATTERED SHOWERS AND STORMS COULD BRING LOCALLY HIGHER WINDS AND SEAS...ESPECIALLY THIS MORNING. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...BERMUDA HIGH PRESSURE OFFSHORE AND A PIEDMONT TROUGH INLAND WILL DRIVE THE REGIME THROUGH MID-WEEK. THESE TWO FEATURES IN TANDEM WILL CREATE SW WINDS...WHICH WILL BE PREDOMINANTLY 10-15 KTS...BUT WILL LIKELY INCREASE EACH EVENING TO 20 KTS AS THE GRADIENT TIGHTENS THANKS TO THE DAILY SHARPENING OF THE PIEDMONT TROUGH. THE PERSISTENT SW FLOW AND LONG FETCH WILL CREATE A WAVE SPECTRUM COMPRISED OF BOTH SW WIND WAVE AND A GROWING SE SWELL. WAVE HEIGHTS OF 3-5 FT CAN BE EXPECTED THROUGH THE PERIOD...AND PERIODIC SCEC STATEMENTS MAY BE REQUIRED. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 AM MONDAY...PERSISTENT BERMUDA HIGH PRESSURE AND PIEDMONT TROUGH WILL CONTINUE THROUGH THE EXTENDED IN A TYPICAL SUMMERTIME FASHION. THE GRADIENT WILL BECOME PINCHED AT TIMES DUE TO THE STRENGTH OF THESE FEATURES...ESPECIALLY IN THE EVENING AS THE PIEDMONT TROUGH SHARPENS INLAND FROM THE WATERS. THIS WILL DRIVE SW WINDS OF 10-15 KTS...RISING UP TO 20 KTS IN THE EVENING. SEAS WILL BE PREDOMINANTLY 3-5 FT...BUT SLIGHT INCREASES IN THE EVENINGS MAY NECESSITATE CAUTIONARY OR ADVISORY STATEMENTS AT TIMES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...HAWKINS SHORT TERM...JDW LONG TERM...JDW AVIATION...43
AREA FORECAST DISCUSSION
NWS NORMAN OK
1004 AM CDT MON JUN 29 2015 .UPDATE... ADJUSTED PRECIP/WX THROUGH NOON... && .DISCUSSION... SCATTERED SHOWERS CONTINUE TO DISSIPATE ACROSS SWRN OK/NRN TX THIS MORNING AS MID-LEVEL SUPPORT FROM H850 WINDS CONTINUES TO WEAKEN. DID NOT MAKE ANY IMMEDIATE ADJUSTMENTS TO PRECIP/WX CHCS THIS AFTN. HOWEVER... WILL NEED TO KEEP AN EYE ON THE WEAK SHORT WAVE DROPPING SOUTH OFF THE WRN HIGH PLAINS OF CO/KS INTO THE PANHANDLES THIS AFTN. SKIES CONTINUE TO CLEAR QUICKLY BEHIND THE EXITING/DISSIPATING CONVECTION. SFC DPTS REMAIN IN THE MID/UPPER 60S ACROSS CENTRAL AND SRN OK... WITH SBCAPE VALUES POSSIBLE IN THE 800-1500 J/KG RANGE ACROSS SRN OK/NRN TX THIS EVENING. THE RECENT HRRR IS LIKELY CONTINUING TO OVER-DO CONVECTION... HOWEVER... THE GENERAL LOCATION IS LIKELY FAIRLY ACCURATE... WITH FOCUS ALONG THE WEAK/DIFFUSE SFC BOUNDARY ACROSS SRN OK. EXPECT SCATTERED SHOWERS/ISOLATED THUNDER TO DEVELOP LATE THIS AFTN... WITH MAYBE ONE OR TWO STORMS CAPABLE OF SOME STRONG WIND GUSTS. JTK && .PREV DISCUSSION... /ISSUED 632 AM CDT MON JUN 29 2015/ DISCUSSION... AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW. AVIATION... VFR CONDITIONS AND FAIRLY LIGHT WINDS ARE EXPECTED TO CONTINUE. ISO-SCT TSRA WILL AFFECT KLAW AND KHBR THROUGH 14Z BEFORE WEAKENING. ADDITIONAL ISO TSRA WILL FORM SOUTH OF KPPA-KSWO 18-05Z...BUT COVERAGE WILL BE TOO SPARSE TO MENTION IN THE TAFS. MBS PREV DISCUSSION... /ISSUED 329 AM CDT MON JUN 29 2015/ DISCUSSION... RAIN CHANCES AND HOT WEATHER OVER THE NEXT FEW DAYS ARE THE MAIN CONCERNS. THIS MORNING...ISOLATED TO SCATTERED THUNDERSTORMS HAVE FORMED ACROSS CENTRAL AND SOUTHWESTERN OKLAHOMA. A FEW FACTORS HAVE LED TO THE FORMATION OF THESE STORMS POSSIBLY INCLUDING A WEST TO SOUTHWESTERLY 850 MB JET...SLIGHT MID LEVEL WEAKNESS AND SLIGHT DECREASE IN MID LEVEL TEMPERATURES TO BREAK A WEAK CAP...AND SOME ELEVATED POTENTIAL INSTABILITY. THINK THESE STORMS WILL MOVE SOUTH THIS MORNING. NOT SURE IF THEY WILL WEAKEN. THINK THEY WILL STAY BELOW SEVERE LIMITS AND PRODUCE LOCALLY HEAVY RAINFALL AND FREQUENT LIGHTNING. ADDED/INCREASE RAIN CHANCES THIS MORNING MAINLY NEAR AND SOUTH OF I-40. THIS AFTERNOON AND EVENING...ADDITIONAL ISOLATED TO SCATTERED THUNDERSTORMS WILL OCCUR MAINLY OVER SOUTHERN OKLAHOMA AND NORTH TEXAS WHERE COOLEST 700 MB TEMPERATURES...SLIGHTLY DEEPER MOISTURE...AND WEAKEST CAPPING ARE FORECAST. CANNOT RULE OUT A STRAY SEVERE STORM WITH DAMAGING WINDS...BUT GENERALLY THINK WEAK SHEAR WILL LIMIT SEVERE POTENTIAL. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE. STORMS WILL LIKELY DISSIPATE THROUGH THE NIGHT AS CAPPING STRENGTHENS. TODAY WILL BE HOT AND STAYED CLOSE TO MODEL HIGHS MAINLY IN THE MID 90S. HEAT INDICES ARE FORECAST TO STAY BELOW ADVISORY CRITERIA OF 105 DEGREES. TUESDAY AND WEDNESDAY...HOT WEATHER WILL PREVAIL WITH HIGHS WELL INTO THE 90S. SOME LOCATIONS WILL LIKELY EXCEED 100 DEGREES IN WESTERN AND NORTHERN OKLAHOMA AS WELL AS FAR WESTERN NORTH TEXAS. A HEAT ADVISORY MAY BE NECESSARY...MAINLY NEAR EAST OF A SHAWNEE TO MARIETTA LINE ON TUESDAY WHERE SURFACE DEWPOINT MAY POOL INTO THE LOWER TO MID 70S AND HEAT INDICES HAVE THE HIGHEST CHANCE OF EXCEEDING 105 DEGREES. CAPPING SHOULD BE STRONG ENOUGH FOR NO RAIN OR STORMS TUESDAY THROUGH WEDNESDAY MORNING. WEDNESDAY AFTERNOON THROUGH THURSDAY...A FEW SHOWERS AND THUNDERSTORMS MAY OCCUR AS A WEAK SURFACE BOUNDARY MOVES INTO THE AREA. CAPPING MAY BE QUITE STRONG WITH 700 MB TEMPERATURES +10 TO +13...SO THINK STORM COVERAGE WILL BE SPARSE AT BEST. A STRAY STRONG TO SEVERE STORM WITH LOCALLY HEAVY RAIN MAY OCCUR. THURSDAY WILL NOT BE QUITE AS HOT COMPARED TO TUESDAY AND WEDNESDAY. THURSDAY NIGHT THROUGH SUNDAY...RAIN CHANCES ARE FORECAST TO INCREASE OVER AREA DUE TO SOME MID/UPPER LEVEL TROUGHING. DON/T EXPECT ALL DAY RAINS...BUT HEAVY RAINFALL COULD OCCUR AT TIMES. WIDESPREAD SEVERE STORMS SEEM UNLIKELY DUE TO WEAK SHEAR. TEMPERATURES WILL BE A BIT COOLER. MBS && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 94 70 96 74 / 10 10 0 0 HOBART OK 96 69 98 73 / 30 20 0 0 WICHITA FALLS TX 96 72 97 75 / 60 20 0 0 GAGE OK 92 66 97 73 / 10 10 0 0 PONCA CITY OK 93 69 98 78 / 0 0 0 0 DURANT OK 95 71 95 72 / 20 20 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1022 AM CDT MON JUN 29 2015 .UPDATE... RADAR COVERAGE SHOWS MOST OF THE SHOWER ACTIVITY AHEAD OF A WEAK SURFACE FRONT SHOULD FAVOR THE SOUTHERN COUNTIES THIS MORNING...BUT SOME EXPANSION TO THE REST OF THE MID-STATE IS ANTICIPATED AS SUGGESTED BY HRRR OUTPUT THROUGH 00Z. THE KBNA SOUNDING FROM THIS MORNING SHOWS MOISTURE LIMITED TO THE 750MB- 550MB LAYER AND A PW VALUE OF ABOUT 1.4 INCHES...SO ISO TO SCT CONVECTION IS ANTICIPATED...WITH A MARGINAL RISK FOR SEVERE WEATHER PER SPC...WITH SOME BRIEF HEAVY DOWNPOURS AND OCCASIONAL LIGHTNING. && .PREV DISCUSSION... /ISSUED 625 AM CDT MON JUN 29 2015/ 12Z AVIATION UPDATE... VFR. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE IN THE FORECAST FOR THE DURATION OF THE TAF PERIOD. HIGHEST CHANCES WILL BE THIS AFTERNOON...AND HAVE VCTS IN THE FORECAST FOR THAT TIMEFRAME ATTM. IF THUNDERSTORMS PASS THROUGH TAF SITES...GUSTY WINDS AND REDUCED VISIBILITY FROM HEAVY RAINFALL MAY OCCUR. OTHERWISE...SOUTHWEST WINDS WILL PICK UP THIS MORNING TO AROUND 10 TO 15 KNOTS WITH GUSTS AROUND 20 KNOTS. WINDS SHOULD CALM DOWN LATE IN THE AFTERNOON OR EARLY EVENING BELOW 10 KNOTS. PREV DISCUSSION... /ISSUED 409 AM CDT MON JUN 29 2015/ DISCUSSION... SHOWERS AND A FEW EMBEDDED THUNDERSTORMS CONTINUE TO MOVE ACROSS MIDDLE TENNESSEE THIS EARLY MORNING. THIS WILL BE THE MAIN WEATHER FEATURE TODAY WITH THE BEST CHANCES FOR PRECIPITATION DURING THE MORNING HOURS ACROSS LOCATIONS WEST OF INTERSTATE 65 AND AFTERNOON HOURS ACROSS THE EAST. THINK HIGHS WILL HAVE TIME TO RECOVER FROM THE ADDITIONAL CLOUD COVER AND PRECIP ESPECIALLY WEST WITH MOST LOCATIONS A FEW DEGREES HIGHER THAN YESTERDAY WITH 80S EXPECTED. ANOTHER UPPER LEVEL IMPULSE WILL PUSH ACROSS THE AREA TONIGHT BRINGING ADDITIONAL CHANCES FOR PRECIPITATION. LOWS WILL FALL INTO THE MID TO UPPER 60S TONIGHT. WITH THE UPPER LEVEL TROUGH FIRMLY IN PLACE ACROSS THE GREAT LAKES REGION...THE FORECAST AREA WILL REMAIN IN MOSTLY NORTHWEST FLOW ALOFT ALLOWING SEVERAL UPPER LEVEL IMPULSES TO SPARK NUMEROUS CHANCES FOR STORMS THROUGH ALMOST THE ENTIRE FORECAST PERIOD. ZONAL FLOW FINALLY DEVELOPS BY THE END OF NEXT WEEKEND DECREASING CHANCES FOR RAIN. THE GOOD NEWS ON THAT FRONT IS THAT TEMPERATURES WILL REMAIN NEAR SEASONAL NORMALS WITH MOST LOCATIONS IN THE MID TO UPPER 80S THROUGH THE WEEK. BUT UNFORTUNATELY...WE WILL SAY GOODBYE TO THE LOWER DEWPOINTS WITH HUMID CONDITIONS RETURNING. PINPOINTING THE BEST CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE QUITE DIFFICULT SINCE TIMING AND STRENGTH OF THESE UPPER LEVEL IMPULSES WILL DEVIATE FROM DAY TO DAY. HOWEVER...MODELS HAVE BEEN FAIRLY CONSISTENT THAT WEDNESDAY NIGHT AND INTO THURSDAY LOOK TO HAVE THE BEST CHANCES FOR PRECIPITATION OUT OF THE ENTIRE FORECAST PERIOD. WITH THE FOURTH OF JULY WEEKEND AROUND THE CORNER... SHOWERS AND THUNDERSTORMS DO LOOK TO BE A POSSIBILITY...BUT THINK THE AREA WILL BE TRANSITIONING TO MORE OF A DIURNAL CONVECTION PATTERN OF MOSTLY AFTERNOON AND EVENING STORMS. DEFINITELY SOMETHING TO WATCH ESPECIALLY IF YOU HAVE ANY OUTDOOR PLANS THIS UPCOMING WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 86 69 88 68 / 30 40 50 30 CLARKSVILLE 85 68 86 68 / 30 30 50 40 CROSSVILLE 81 66 81 65 / 30 30 60 50 COLUMBIA 86 68 87 68 / 30 40 50 30 LAWRENCEBURG 86 69 86 68 / 30 40 50 30 WAVERLY 85 69 87 69 / 30 30 50 30 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05
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AREA FORECAST DISCUSSION
NWS LA CROSSE WI
620 AM CDT MON JUN 29 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 312 AM CDT MON JUN 29 2015 LATEST WATER VAPOR SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES AND UPPER LEVEL RIDGE OVER THE WESTERN UNITED STATES INTO THE CANADIAN ROCKIES. SEVERAL PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT PER WATER VAPOR SATELLITE IMAGERY. ONE IMPULSE WAS PRODUCING SHOWERS OVER CENTRAL AND SOUTHWEST WISCONSIN PER KARX RADAR. DUE TO MOIST BOUNDARY LAYER AND MOSTLY CLEAR SKIES PATCHY FOG HAS DEVELOPED OVER PARTS OF THE FORECAST AREA. MAIN FORECAST CONCERNS TODAY INTO THIS EVENING ARE PRECIPITATION CHANCES. THE 29.00Z GFS/NAM INDICATE NEXT SHORTWAVE TROUGH NEAR LAKE WINNIPEG TO IMPACT THE FORECAST AREA THIS AFTERNOON INTO THIS EVENING. THE 29.00Z GFS/NAM SHOW PV ADVECTION IN THE 500-300MB LAYER/STEEP LOW LEVEL LAPSE RATES/INSTABILITY WITH SHORTWAVE TROUGH. THE LATEST HIGH RESOLUTION MODELS...ARW/NMM/HRRR...SHOW DIFFERENCES IN TIMING OF THE CONVECTION INTO THE FORECAST AREA TODAY INTO THIS EVENING. THE 29.00Z DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST CONVECTION WILL DEVELOP MID TO LATE THIS AFTERNOON AND CONTINUE INTO THE EVENING HOURS ACROSS MUCH OF THE FORECAST AREA. HAVE TRENDED THE HIGHER PRECIPITATION CHANCES AFTER 21Z TODAY TO 03Z TUESDAY. THE NEXT CONCERN ARE SEVERE POSSIBILITIES. THE 29.00Z GFS/NAM/RAP SHOW UP TO 20 KNOTS OF 0-3KM SHEAR AND BUFKIT SOUNDINGS INDICATE MANLY STRAIGHT HODOGRAPHS THROUGH THIS LAYER LATE THIS AFTERNOON/THIS EVENING MAINLY WEST OF THE MISSISSIPPI RIVER. THE 29.00Z GFS/NAM AND 29.03Z RAP BUILD UP TO 2000 J/KG OF SURFACE BASE CAPE ACROSS THE FORECAST AREA. WITH WEAK SHEAR IN THE 0-3KM LAYER...LARGE HAIL WILL BE A POSSIBILITY WITH SOME OF THE STRONGER THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 312 AM CDT MON JUN 29 2015 WEAK SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND SHORTWAVE ENERGY PUSHES INTO SOUTHERN/EASTERN WISCONSIN TUESDAY. WITH THE 29.00Z GFS/NAM SUGGEST STEEP LOW LEVEL LAPSE RATE AND THE BETTER INSTABILITY OVER THE EASTERN FORECAST AREA...SMALL PRECIPITATION CHANCES CONTINUE TO BE WARRANTED OVER THIS AREA. THE 29.00Z GFS/NAM/ECMWF ARE TRENDING A FARTHER WESTWARD SOLUTION WITH THE PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT WEDNESDAY INTO WEDNESDAY NIGHT. PLUS...SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND NORTHERN WISCONSIN AND DEVELOP A DRIER NORTHEASTERLY FLOW INTO THE FORECAST AREA. HAVE REDUCE PRECIPITATION CHANCES ACROSS THE WESTERN PORTIONS OF THE FORECAST AREA...BASED ON THE DRIER NORTHEASTERLY FLOW AND WESTERN SHIFT OF THE SHORTWAVE ENERGY. MAIN FORECAST CONCERNS THURSDAY INTO SUNDAY ARE PRECIPITATION CHANCES THROUGH THE PERIOD. THE 29.00Z GFS/ECMWF/GEM ARE IN AGREEMENT IN WEAKENING UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION/EASTERN UNITED STATES AND DEVELOP WEST TO EAST ZONAL FLOW ALOFT BY 12Z SUNDAY ACROSS THE NORTHERN TIER STATES. THE BIGGEST DIFFERENCE BETWEEN THE 29.00Z GFS/ECMWF/GEM IS TIMING OF THE INDIVIDUAL IMPULSES INTO THE GREAT LAKES REGION THROUGH THE FORECAST PERIOD. THE 29.00Z MODELS SUGGEST ENOUGH LIFT/FORCING/MOISTURE CONVERGENCE WITH THE IMPULSES. WILL CONTINUE TREND OF PERIODIC SMALL PRECIPITATION CHANCES THROUGH MUCH OF THE FORECAST PERIOD. TEMPERATURES WILL REMAIN SLIGHTLY BELOW OR NEAR NORMAL DURING THE FORECAST PERIOD. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 620 AM CDT MON JUN 29 2015 LIGHT WINDS...MOSTLY CLEAR SKIES AND RECENT RAINS HAVE ONCE AGAIN ALLOWED AREAS OF MVFR/IFR BR/FG/CIGS TO DEVELOP ACROSS THE AREA. THIS WILL IMPACT THE TAF SITES THRU 13Z TO 14Z THIS MORNING...BEFORE LATE JUNE SUNSHINE AND NORTHWEST WINDS WORK TO DISSIPATE THE BR/FG. MIDDLE OF THE DAY FROM 14-22Z APPEARS QUIET WITH SCT VFR CUMULUS AND LIGHT NORTHWEST WINDS. THIS AHEAD OF THE NEXT SHORTWAVE AND ROUND OF SCT SHRA/TSRA TO MOVE ACROSS THE AREA. PRESENT TIMING CONSENSUS AMONG THE GUIDANCE WOULD SPREAD THE SHRA/TSRA ACROSS THE TAF SITES IN THE 22Z-01Z TIME-FRAME...THOUGH A FEW SHRA/TSRA COULD BE IN THE AREA AS EARLY AS 20Z. WILL LEAVE A VCTS/CB MENTION AT BOTH KRST/KLSE IN THE 22Z-01Z PERIOD. SUBSIDENCE/DRYING SPREAD SOUTH ACROSS THE AREA FOR THE LATER EVENING/OVERNIGHT HOURS INTO TUE MORNING...FOR GENERALLY GOOD VFR CONDITIONS AFTER THE SHRA/TSRA EXIT. MAY YET NEED A BR MENTION AT KLSE AFTER 09Z TONIGHT BUT LEFT THAT OUT FOR NOW AS RADIATIONAL FOG SIGNAL FOR TONIGHT NOT AS STRONG AS THE PAST COUPLE NIGHTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...DTJ LONG TERM....DTJ AVIATION.....RRS
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
255 PM PDT MON JUN 29 2015 .SYNOPSIS...A SIGNIFICANT WARMING TREND WILL CONTINUE ACROSS INLAND PORTIONS OF THE REGION THROUGH WEDNESDAY AS HIGH PRESSURE BUILDS OVER THE WESTERN UNITED STATES. A SLIGHT COOLING TREND IS THEN EXPECTED FOR THE LATTER HALF OF THE WEEK AS THE HIGH PRESSURE WEAKENS AND RETREATS INLAND. && .DISCUSSION...AS OF 02:54 PM PDT MONDAY...MANY INLAND LOCATIONS ARE REPORTING TEMPERATURES IN THE 90S THIS AFTERNOON AS HIGH PRESSURE OVER THE WESTERN CONUS CONTINUES TO BUILD TOWARD THE WEST COAST. IN ADDITION...THE LOW LEVEL CLOUDS HAVE PUSHED WELL OFF OF THE COAST THIS AFTERNOON DESPITE A MARINE LAYER AT AROUND 1200 FEET DEEP. HOWEVER...THE MARINE INFLUENCE AND WEAK ONSHORE FLOW HAS HELD COASTAL TEMPERATURES GENERALLY IN THE 60S TO LOWER 70S. THE INLAND WARMING TREND IS FORECAST TO CONTINUE THROUGH MIDWEEK BEFORE REACHING A PEAK ON WEDNESDAY AFTERNOON. MOST INLAND AREAS AWAY FROM THE COAST AND BAYS WILL SEE AFTERNOON TEMPERATURES WARMING INTO THE 90S TO AS HIGH AS 108 IN THE WARMEST INLAND VALLEYS AND HIGHER ELEVATIONS BOTH TUESDAY AND WEDNESDAY. COASTAL LOCATIONS WILL LIKELY WARM INTO THE UPPER 60S TO 70S WITH A PERSISTENT LIGHT ONSHORE FLOW. MEANWHILE...THE FORECAST MODELS CONTINUE TO SHOW MID- LEVEL MOISTURE ADVECTION OVER THE STATE THROUGH LATE WEEK AS MONSOONAL MOISTURE IS PULLED NORTHWARD ON THE WEST SIDE OF THE MID/UPPER LEVEL HIGH. AT THIS TIME...THE BEST CHANCES FOR CONVECTION WILL BE EAST OF OUR REGION WHERE GREATER INSTABILITY AND MOISTURE IS EXPECTED. HOWEVER...THE LATEST GFS MODEL INDICATES INCREASED POTENTIAL FOR CONVECTION OVER OUR REGION THURSDAY AND FRIDAY. WILL CLOSELY MONITOR THE FORECAST MODELS AND LOOK FOR RUN-TO-RUN CONSISTENCY BEFORE ADDING A MENTION OF THUNDERSTORMS IN THE FORECAST. OTHERWISE...MUCH OF THE REGION IS FORECAST TO EXPERIENCE DRY WEATHER CONDITIONS THROUGH THE UPCOMING WEEKEND WITH HIGH PRESSURE ALOFT. TEMPERATURES WILL BEGIN TO COOL REGION-WIDE LATE IN THE WEEK AS THE MID/UPPER LEVEL RIDGE SLOWLY WEAKENS AND RETREATS INLAND AWAY FROM THE COAST. WITH THE AFOREMENTIONED MID-LEVEL MOISTURE ADVECTION THROUGH LATE WEEK...DO EXPECT AN INCREASE OF MID/HIGH LEVEL CLOUDS OVER MUCH OF THE REGION. THIS TOO WILL AID IN THE COOLING TREND...ESPECIALLY OVER THE INTERIOR. && .AVIATION...AS OF 11:15 AM PDT MONDAY... STRATUS RETREATING FROM INLAND VALLEYS THIS MORN PER THE NORM WITH A STUBBORN PATCH OF IFR CIGS LINGERING NEAR KMRY. EXPECT VFR FOR THE REMAINDER OF THE DAY WITH PREDOMINATELY ONSHORE FLOW. WINDS THIS AFTERNOON WILL BE SLIGHTLY STRONGER THAN YESTERDAY WINDS. MODELS APPEAR TO HAVE INITIALIZED LOW LEVEL MOISTURE VERY POORLY WITH THE 12Z RUNS... SO LATEST TAFS ARE RELYING MORE ON THE RUC13 AND PATTERN RECOGNITION THAN USUAL. PATTERN RECOGNITION SAYS AS HIGH PRESSURE BUILDS... MARINE LAYER WILL COMPRESS INTO LOW LEVELS... LEADING TO A THINNER DECK... BUT WITH MORE INVASIVE CIGS. LOOK FOR LIFR/IFR CIGS TO DOMINATE AFTER MIDNIGHT INTO SUNRISE TOMORROW. INCREASING SUBSIDENCE MAY ALSO RESULT IN LOCAL...BRIEF DRIZZLE ALONG THE COAST. VICINITY OF KSFO...VFR. WEST WINDS SUST 15 TO 20 KT WITH GUSTS TO 25 KT. MVFR CIGS RETURN AFTER 04Z... WITH IFR BY 08-10Z. KSFO BRIDGE APPROACH...SAME AS SFO. MONTEREY BAY AREA TERMINALS... PATCH OF LOW HANGING CLOUDS DIRECTLY OVER KMRY TERMINAL... ELSEWHERE... VFR. WEST WINDS AOA 10 KT WITH GUSTS TO 15 KT. RETURN OF MVFR/IFR AFTER 02Z. && .MARINE...AS OF 02:54 PM PDT MONDAY...HIGH PRESSURE WILL CONTINUE TO BRING MODERATE GUSTY NORTHWEST WINDS OVER THE COASTAL WATERS THIS AFTERNOON AND THROUGH TONIGHT. WINDS DECREASE AFTER TUESDAY AS A THERMAL TROUGH OVER THE INTERIOR SHIFTS TO THE COAST. && .MTR WATCHES/WARNINGS/ADVISORIES... .TNGT...SCA...SF BAY UNTIL 9 PM SCA...PIGEON PT TO PT PINOS 0-10 NM UNTIL 9 PM SCA...PT ARENA TO PT REYES 0-10 NM SCA...PT ARENA TO PIGEON PT 10-60 NM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 3 AM && $$ PUBLIC FORECAST: RGASS AVIATION: DRP MARINE: DRP VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
129 PM PDT MON JUN 29 2015 .SYNOPSIS... HIGH PRESSURE OVER THE GREAT BASIN AND LOW PRESSURE OFF THE CALIFORNIA AND BAJA COASTS WILL CONTINUE TO DIRECT A FLOW OF MID AND HIGH LEVEL MONSOONAL MOISTURE ACROSS SOUTHERN CALIFORNIA FOR MUCH OF THE WEEK. THIS WILL SUPPORT A CHANCE OF THUNDERSTORMS THROUGH FRIDAY MAINLY NEAR THE MOUNTAINS AND PORTIONS OF THE DESERTS DURING THE AFTERNOON AND EARLY EVENING HOURS. SLOW DRYING IS POSSIBLE THIS WEEKEND. TEMPERATURES WILL BE ABOVE AVERAGE THROUGH WEDNESDAY...THEN COOL TO NEAR TO SLIGHTLY BELOW AVERAGE FOR THURSDAY THROUGH THE WEEKEND AS HIGH PRESSURE ALOFT WEAKENS. A SHALLOW MARINE LAYER AND WEAK ONSHORE FLOW WILL BRING PATCHY NIGHT AND MORNING LOW CLOUDS AND FOG NEAR THE COAST AND WESTERN VALLEYS AT TIMES. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... RADAR HAS BEEN SHOWING SHOWERS AND THUNDERSTORMS POPPING OVER THE SOUTHERN SAN DIEGO COUNTY MOUNTAINS AND THE MOUNTAINS OF NORTHERN BAJA...AS SKIES HAVE CLEARED ENOUGH TODAY TO ALLOW FOR INCREASED DAY- TIME HEATING AND INSTABILITY. LATEST SPC MESOANALYSIS SHOWS THAT SURFACE BASED CAPE HAS INCREASED TO NEAR 500-1000 J/KG OVER THE SAN DIEGO MOUNTAINS. THE THUNDERSTORMS/SHOWERS ARE MOVING FAIRLY QUICKLY TO THE NORTHWEST HOWEVER...AND DISSIPATING AFTER THEY MOVE OFF OF THE MOUNTAINS AND ARE CUT OFF FROM THE LIFT PROVIDED BY THE CONVERGENCE BOUNDARY THAT HAS SET UP OVER THE MOUNTAINS. DUE TO THE FAST SPEEDS OF THE CELLS...THE FLASH FLOOD THREAT IS LOW. HIGHEST RAINFALL TOTAL SO FAR WAS 0.20 INCHES AT CAMPO. THE 19Z HRRR SHOWS THE CELLS CONTINUING TO DEVELOP NORTH ALONG THE MOUNTAIN SPINE INTO THE RIVERSIDE COUNTY MOUNTAINS AND INTO THE SAN BERNARDINO COUNTY MOUNTAINS NEAR BIG BEAR...WHILE ANVIL DEBRIS BRING POSSIBLE SPRINKLES TO THE VALLEYS AND COAST. THE PLENTIFUL CLOUDS THAT WERE OVER THE AREA THIS MORNING HAS LED TO COOLER CONDITIONS FOR THE COAST AND VALLEYS...WHILE THE BETTER CLEARING OVER THE MOUNTAINS AND DESERTS HAS RESULTED IN TEMPERATURES THAT ARE SEVERAL DEGREES HIGHER THAN 24 HOURS AGO IN MANY LOCATIONS. ON WATER VAPOR SATELLITE...A RIDGE CAN BE SEEN OVER THE GREAT BASIN...WITH A LOW FAR SOUTHWEST OF LOS ANGELES. THIS POSITIONING OF THE RIDGE AND TROUGH IS RESULTING IN THE MOIST SOUTHEAST FLOW OVER THE REGION TODAY. IT APPEARS THAT THERE WILL BE BETTER INSTABILITY ON TUESDAY AND WEDNESDAY WITH LESS CLOUD COVER AND STILL A DECENT AMOUNT OF MOISTURE IN THE FORM OF 1.3-1.6 INCHES OF PRECIPITABLE WATER. HOWEVER...IT STILL LOOKS LIKE MOST OF THE MOISTURE WILL BE CONFINED ABOVE 600 MB. NEVERTHELESS...CHANCES FOR AFTERNOON THUNDERSTORMS/SHOWERS OVER THE MOUNTAINS AND DESERTS WILL CONTINUE FOR TUESDAY AND WEDNESDAY...AND ALSO INTO THURSDAY AND FRIDAY...AS THE RIDGE OVER THE GREAT BASIN REMAINS IN PLACE...RESULTING IN CONTINUED MOIST SOUTHEASTERLY FLOW. STILL...MOST OF THIS MOISTURE STAYS ABOVE 600 MB...SO NO HUGE THUNDERSTORM OUTBREAKS ARE EXPECTED AT THE MOMENT. THE MODELS ARE ALSO HINTING AT AN EASTERLY WAVE AND ASSOCIATED MOISTURE/INSTABILITY MOVING OVER SOUTHERN CALIFORNIA FROM THE EAST WEDNESDAY NIGHT INTO THURSDAY MORNING WHICH COULD BRING NOCTURNAL ELEVATED SHOWERS AND THUNDERSTORMS TO THE MOUNTAINS AND DESERTS. IN FACT...THE NAM12 PRECIPITATION OUTPUT SHOWS SCATTERED PRECIPITATION OVER THE FORECAST AREA DURING THAT TIME. MAY NEED TO EXPAND THE CHANCES FOR SHOWERS/THUNDERSTORMS TO AREAS FURTHER WEST FOR THAT TIME-PERIOD IF MODELS CONTINUE TO SHOW THIS FEATURE. AS FAR AS TEMPERATURES GO...SOME WARMING IS LIKELY TUESDAY...WITH DAY-TIME HIGHS CONTINUING AT 5-10 DEGREES ABOVE NORMAL ON WEDNESDAY...DUE TO OVERALL LESS CLOUDS AND STRONGER HIGH PRESSURE ALOFT. WITH THE RIDGE WEAKENING THURSDAY AND FRIDAY...EXPECT COOLING WITH TEMPERATURES FALLING TO NEAR TO SLIGHTLY BELOW NORMAL. THE 12Z ECMWF HAS TRENDED TOWARD THE 12Z GFS WHICH SHOWS SLOWER DRYING DURING THE WEEKEND AND INTO EARLY NEXT WEEK AS THE RIDGE MOVES EAST OVER THE FOUR CORNERS REGION. IT DOES NOT LOOK LIKE SIGNIFICANT DRYING TAKES PLACE UNTIL LATE MONDAY AS DRY SOUTHWESTERLY FLOW ALOFT KICKS IN. NEVERTHELESS...THE AMOUNT OF MOISTURE LOOKS PRETTY MARGINAL ON SATURDAY...WITH A POSSIBLE IMPULSE OF MOISTURE MOVING IN ON SUNDAY. THE FORECAST FOR THE WEEKEND REMAINS DRY FOR NOW. THE COOLING CONDITIONS MAY CONTINUE INTO THE WEEKEND...WITH GRADUAL WEAKENING OF THE RIDGE. LOOK FOR THE PATCHY NIGHT AND MORNING MARINE LAYER STRATUS TO CONTINUE OVER THE COASTAL AND WESTERN VALLEYS THROUGH THE FORECAST PERIOD. && .AVIATION... 292020Z...COAST/VALLEYS...MAINLY BKN CLOUDS AOA 10000 FT MSL AND ISOLATED LIGHT SHOWERS. PATCHY STRATUS REDEVELOPING LATE TONIGHT/EARLY TUE MORNING...EXTENDING ABOUT 5-10 MILES INLAND...AND FROM ABOUT KCRQ SOUTHWARD. BASES NEAR 800 FT MSL AND TOPS 1200 FEET MSL. STRATUS DISSIPATING AROUND 30/16Z TUESDAY MORNING. CONFIDENCE IN TIMING/OCCURRENCE IS LOW. RISK OF BKN LOW CLOUDS AT KSNA IS STILL VERY LOW...SO WILL LEAVE IT OUT OF THE KSNA TAF. MTNS/DESERTS...SCT-BKN CLOUDS AOA 10000 FT MSL WILL CONTINUE THROUGH TUESDAY. CU/TCU DEVELOPING MAINLY AFTERNOONS WITH A SLIGHT CHANCE OF SHOWERS/THUNDERSTORMS. THUNDERSTORM TOPS TO NEAR 30000 FT MSL... LOCAL GUSTY SURFACE WINDS...AND LOCAL VIS RESTRICTIONS IN HEAVY RAIN POSSIBLE. && .MARINE... 145 PM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH FRIDAY. && .SKYWARN... THERES A CHANCE THAT SKYWARN WILL NEED TO BE ACTIVATED THIS AFTERNOON. WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE...SMALL
AREA FORECAST DISCUSSION
NWS SAN FRANCISCO BAY AREA
1105 AM PDT MON JUN 29 2015 .SYNOPSIS...TEMPERATURES WILL CONTINUE TO RISE THROUGH WEDNESDAY AS A RIDGE OF HIGH PRESSURE SHIFTS WESTWARD OVER CALIFORNIA. TEMPERATURES WILL PEAK WEDNESDAY WITH HIGHS REACHING INTO THE LOW 100S OVER INLAND AREAS. A SLIGHT COOL DOWN IS EXPECTED THROUGH THE SECOND HALF OF THE WEEK. && .DISCUSSION...AS OF 09:03 AM PDT MONDAY...THE LATEST VISIBLE SATELLITE IMAGERY SHOWS LOW CLOUDS SLOWLY DISSIPATING OVER INLAND AREAS AS THE MARINE LAYER REMAINS AROUND 1500 FEET DEEP. SHOULD SEE MOSTLY SUNNY CONDITIONS WITH WARMER TEMPERATURES OVER THE REGION TODAY WITH THE LOW CLOUDS JUST OFF THE COASTLINE. AFTER LOOKING AT THE LATEST SHORT-TERM FORECAST GUIDANCE...HAVE REMOVED THE MENTION OF THUNDERSTORMS ACROSS MUCH OF THE REGION FOR TODAY. IT APPEARS THE MID-LEVEL MOISTURE ADVECTION WILL BE A BIT SLOWER AND WILL PREDOMINATELY STAY TO OUR EAST. HOWEVER...HAVE LEFT A SLIGHT CHANCE OVER THE MOUNTAINS OF SAN BENITO AND INTERIORMONTEREY COUNTY AS THE MOISTURE ADVECTS NORTHWARD THIS EVENING AND SOME INSTABILITY REMAINS. OVERALL THINKING IS THAT MOST LOCATIONS WILL REMAIN DRY TODAY WITH ANY CONVECTION TO STAY WELL TO OUR EAST OF THE INTERIOR PORTION OF THE STATE. && .PREV DISCUSSION...AS OF 3:41 AM PDT MONDAY...MILD CONDITIONS PREVAIL ACROSS THE REGION TONIGHT. TEMPERATURES ACROSS THE REGION ARE IN THE MID 50S TO LOWER 60S BENEATH A BLANKET OF A MIXED OF LOW CLOUDS AT THE SURFACE AND HIGH LEVEL MOISTURE STREAMING IN ALOFT. SATELLITE IMAGERY CONTINUES TO SHOW A STEADY STREAM OF MONSOONAL MOISTURE ADVECTING NORTHWARD ACROSS OUR AREA. HOWEVER RADAR HAS NOT PICKED UP ON ANY SHOWER ACTIVITY OVER THE DISTRICT BUT RATHER TO THE EAST OVER THE SIERRA. LATEST MODEL GUIDANCE HAS BACK OFF ON THE POTENTIAL FOR CONVECTION OVER THE REGION TODAY. THEREFORE THUNDERSTORMS HAVE BEEN REMOVED FROM THE FORECAST THROUGH THE MORNING HOURS. DIDN/T WANT TO REMOVE ALL MENTION OF THUNDERSTORM FOR THIS AFTERNOON SINCE THIS IS THE FIRST RUN OF THE MODELS THAT HAS BACKED OFF ON THE CHANCE OF THUNDERSTORMS AND THE MODELS MAY BE FLIP FLOPPING BETWEEN SOLUTIONS. MODELS REMAIN IN GOOD AGREEMENT WITH RESPECT TO THE WARMING TREND EXPECTED OVER THE NEXT FEW DAY. HIGH PRESSURE WILL CONTINUE TO BUILD OVER THE WESTERN U.S. AS IT GRADUALLY INCHES WESTWARD OVER CALIFORNIA. THIS WILL RESULT IN A GRADUAL WARM UP ACROSS THE STATE. TEMPERATURES ARE EXPECTED TO PEAK ON WEDNESDAY WITH HIGHS IN THE 70S AND 80S AT THE COAST AND BAYS AND 90S TO LOW 100S EXPECTED OVER INLAND AREAS. A HEAT ADVISORY MAY BE IN ORDER FOR WEDNESDAY AS TEMPERATURES CLIMB INTO RECORD TERRITORY. WILL LET THE DAY SHIFT PIN POINT THE TIMING AND LOCATION. A GRADUAL COOL DOWN IS EXPECTED THROUGH THE SECOND HALF OF THE WEEK AS THE HIGH SLOWLY WEAKENS. && .AVIATION...AS OF 11:15 AM PDT MONDAY... STRATUS RETREATING FROM INLAND VALLEYS THIS MORN PER THE NORM WITH A STUBBORN PATCH OF IFR CIGS LINGERING NEAR KMRY. EXPECT VFR FOR THE REMAINDER OF THE DAY WITH PREDOMINATELY ONSHORE FLOW. WINDS THIS AFTERNOON WILL BE SLIGHTLY STRONGER THAN YESTERDAY WINDS. MODELS APPEAR TO HAVE INITIALIZED LOW LEVEL MOISTURE VERY POORLY WITH THE 12Z RUNS... SO LATEST TAFS ARE RELYING MORE ON THE RUC13 AND PATTERN RECOGNITION THAN USUAL. PATTERN RECOGNITION SAYS AS HIGH PRESSURE BUILDS... MARINE LAYER WILL COMPRESS INTO LOW LEVELS... LEADING TO A THINNER DECK... BUT WITH MORE INVASIVE CIGS. LOOK FOR LIFR/IFR CIGS TO DOMINATE AFTER MIDNIGHT INTO SUNRISE TOMORROW. INCREASING SUBSIDENCE MAY ALSO RESULT IN LOCAL...BRIEF DRIZZLE ALONG THE COAST. VICINITY OF KSFO...VFR. WEST WINDS SUST 15 TO 20 KT WITH GUSTS TO 25 KT. MVFR CIGS RETURN AFTER 04Z... WITH IFR BY 08-10Z. KSFO BRIDGE APPROACH...SAME AS SFO. MONTEREY BAY AREA TERMINALS... PATCH OF LOW HANGING CLOUDS DIRECTLY OVER KMRY TERMINAL... ELSEWHERE... VFR. WEST WINDS AOA 10 KT WITH GUSTS TO 15 KT. RETURN OF MVFR/IFR AFTER 02Z. && .MARINE...AS OF 10:56 AM PDT MONDAY...AN AREA OF HIGH PRESSURE STRENGTHENING OVER THE REGION WILL LEAD TO INCREASING NORTHERLY WINDS TODAY. THESE WINDS WILL OCCASIONALLY BE GUSTY AND LEAD TO LOCALLY STEEP WIND WAVES. WINDS WILL DECREASE AFTER TUESDAY AS A THERMAL TROUGH OVER THE INTERIOR SHIFTS TO THE COAST. && .MTR WATCHES/WARNINGS/ADVISORIES... .TDAY...SCA...SF BAY FROM NOON SCA...PIGEON PT TO PT PINOS 0-10 NM FROM NOON SCA...PT ARENA TO PT REYES 0-10 NM FROM 3 PM SCA...PT ARENA TO PIGEON PT 10-60 NM FROM 3 PM SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM FROM 3 PM && $$ PUBLIC FORECAST: RGASS AVIATION: MM MARINE: DRP VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO FOLLOW US ON FACEBOOK AND TWITTER AT: WWW.FACEBOOK.COM/NWSBAYAREA WWW.TWITTER.COM/NWSBAYAREA
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1040 AM PDT MON JUN 29 2015 .SYNOPSIS... A WARM AND HUMID AIR MASS WILL OCCUR ACROSS THE AREA THROUGH THE WEEK AS A HIGH PRESSURE REMAINS ANCHORED OVER THE GREAT BASIN. SOUTHEAST FLOW ALOFT WILL BRING ENOUGH MOISTURE AND UNSTABLE AIR TO CREATE A SLIGHT CHANCE OF THUNDERSTORMS AND SHOWERS THIS WEEK...MAINLY IN THE MOUNTAINS AND DESERTS. A COOLING TREND WILL OCCUR FOR THE END OF THE WEEK AS A LOW PRESSURE APPROACHES. && .UPDATE... HIGH PRESSURE REMAINS CENTERED OVER THE GREAT BASIN THIS MORNING. SOUTHEAST FLOW ALOFT CONTINUES TO PUMP MAINLY MIDDLE AND HIGH LEVEL MOISTURE ACROSS THE AREA TODAY. A FEW SHOWERS ARE MOVING NORTH ACROSS SOUTHERN CALIFORNIA ASSOCIATED WITH A WAVE OVER BAJA CALIFORNIA. MODEL SOLUTIONS ARE OFFERING UP A MIXED BAG OF VARYING IDEAS OF HOW TO HANDLE THE INSTABILITY WITH THE WAVE...BUT MOST MODEL BRING THE KINK IN THE MIDDLE LEVEL WINDS OVER THE AREA LATER THIS AFTERNOON AND THIS EVENING. RAP AND HRRR SOLUTIONS SEEMS TO BE TAKING A MORE AGGRESSIVE STANCE IN DEVELOPING NEGATIVE LIFTED INDICES AND K INDEX VALUES GREATER THAN 30 MOVING OVER SOUTHERN AND EASTERN LOS ANGELES COUNTY THIS AFTERNOON AND EVENING. WHILE THE PREVIOUS SHIFT REMOVED POPS FOR THE LOS ANGELES COUNTY VALLEYS AND COAST...ISOLATED SHOWERS CANNOT BE RULED OUT FOR THE SAN GABRIEL VALLEY AND LOS ANGELES COUNTY COAST. POPS WERE ADDED BACK FOR THIS AFTERNOON. WITH THE RIDGE IN PLACE ALOFT...A VERY WARM AND HUMID DAY IS SHAPING UP FOR TODAY. THE AREA IS GETTING OFF TO A WARMER START TODAY...BUT MIDDLE AND HIGH LEVEL CLOUDINESS SHOULD CUT INTO TEMPERATURES LATER AS THE WAVE PUSHES NORTH. LOCAL HEAT INDEX VALUES MAY APPROACH CRITICAL VALUES...ESPECIALLY IN LOCATIONS LIKELY CARRIZO AND ACTON THIS AFTERNOON. 950 MB TEMPERATURES LOOK WARMEST TODAY THEN START TO COOL LATER THIS WEEK. STRATUS COVERAGE WILL BE MINIMAL THE NEXT SEVERAL DAYS AS NAM BUFR TIME HEIGHT SECTIONS HAVE LITTLE HUMIDITY IN THE MARINE LAYER. LOCAL 2-KM WRF SOLUTIONS CONTINUE TO MODEL THE STRATUS EXCELLENTLY...AND SUGGEST NO COVERAGE ACROSS THE AREA TONIGHT. && .PREV DISCUSSION... SHORT TERM...NOT MUCH IN THE WAY OF MARINE STRATUS AS ALL OF THE MID AND HIGH LEVEL CLOUDS HAVE REALLY MESSED WITH THE MARINE INVERSION. THE BEST CHC OF LOW CLOUDS WILL BE ACROSS THE CENTRAL COAST. WITH 592 DM HGTS OVERHEAD AND ONLY VERY WEAK ONSHORE FLOW MAX TEMPS WILL BE WELL ABOVE NORMAL EACH DAY ACROSS THE ENTIRE AREA. HUMIDITY WILL BE ABOVE NORMAL AS WELL SO IT WILL ACTUALLY FEEL A LITTLE WORSE THAN IT ACTUALLY IS. INCREASING ONSHORE FLOW WILL BRING A LITTLE COOLING TO THE COASTS AND LOWER VLYS WEDNESDAY. THAT SAID MAX TEMPS ARE RIPE FOR SOME PRETTY BIG BUSTS DUE TO THE HIGH CLOUD FORECAST. LESS CLOUDS THAN FORECAST WILL RESULT IN WARMER THAN FORECAST HIGHS (LIKE SUNDAY) AND VICE VERSA (LIKE SATURDAY) .LONG TERM...NOT MUCH CHANGE THURSDAY THROUGH SATURDAY. THE UPPER HIGH MOVES FROM UTAH TO NEVADA. SKIES SHOULD BE MORE ON THE PARTLY CLOUDY SIDE. THIS WILL ALLOW BETTER INSTABILITY TO DEVELOP OVER THE MTNS. THE MOISTURE SHOULD DIMINISH A LITTLE BUT NOT ENOUGH TO ELIMINATE THE SLIGHT CHC OF AFT AND EVE MTN TSTMS. MAX TEMPS WILL BE RATHER SIMILAR EACH DAY AND WILL REMAIN SLIGHTLY ABOVE NORMAL. ON SUNDAY THE HIGH SHIFTS AWAY TO THE EAST AND A STRONGER UPPER LOW MOVES INTO THE EAST PAC AND SETS UP DRIER SW FLOW OVER THE AREA. THIS SHOULD KILL ANY CHC FOR AFTERNOON TSTMS. HGTS FALL AND THIS WILL BRING A FEW DEGREES OF COOLING. && .AVIATION...29/1800Z... MID/UPPER LEVEL RIDGE OF HIGH PRESSURE CENTERED OVER THE GREAT BASIN WILL SHIFT SOUTHEAST AND SETTLE OVER THE FOUR CORNERS AREA. UPPER LEVEL MODERATE SOUTHEAST WINDS WILL BECOME LIGHT TO MODERATE EAST- SOUTHEAST WINDS AFTER 30/19Z WHILE MID LEVEL MODERATE SOUTHEAST WINDS PREVAIL OVER THE AREA. ISOLATED TSTMS OVER THE MOUNTAINS FROM SLO COUNTY TO LA COUNTY AND ISOLATED SHOWERS OVER TEH LA BASIN AND NEAR SHORE WATERS THROUGH 30/03Z. TSTMS WITH TOPS 40KFT WILL MOVE NORTHWEST APPROXIMATELY 25KT. BASE OF THE MARINE LAYER INVERSION WAS AROUND .5FT THIS MORNING OVER KLAX AND WILL CHANGE LITTLE. MARINE LAYER AT LAX AT 1600Z IS 477 FEET DEEP AND THE INVERSION TOP IS AT 2131 FEET WITH A TEMP OF 28.8 DEGREES C. KLAX...CURRENT SKY/VSBY LIKELY THROUGH THE PERIOD. VERY UNLIKELY CIGS 015 BETWEEN 30/10-30/17Z. KBUR...CURRENT SKY/VSBY LIKELY THROUGH THE PERIOD. VIRTUALLY CERTAIN - 95-100% VERY LIKELY - 80-95% LIKELY - 60-80% CHANCE - 30-60% VERY UNLIKELY - 20% OR LESS && .MARINE...29/900 AM. SMALL CRAFT ADVISORY CONDITIONS WILL LIKELY END SOUTH OF SAN MIGUEL ISLAND THIS AFTERNOON AND CONTINUE NORTH TO PIEDRAS BLANCAS EXCLUDING THE AREA FROM POINT SAL NORTH 0-10 NM THROUGH LATE TONIGHT. OTHERWISE THERE IS A CHANCE SHOWERS WILL DEVELOP NEAR SHORE SOUTH OF POINT MUGU THIS AFTERNOON. THROUGH EARLY WEDNESDAY TWO STORM SYSTEMS WITH GALE TO STORM FORCE WINDS AND WITH A FETCH BETWEEN 200-220 DEGREES RELATIVE TO VENTURA COAST WILL GENERATE SEAS 30-40 FEET SOUTHEAST OF NEW ZEALAND. THE SWELLS WILL BEGIN TO ARRIVE A WEEK FROM TODAY AND BUILD THROUGH TUESDAY. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXMWWLOX). && $$ PUBLIC...HALL/RORKE AVIATION...30 MARINE...30 SYNOPSIS...HALL/SETO WWW.WEATHER.GOV/LOSANGELES
SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NWS LOS ANGELES/OXNARD CA
1018 AM PDT MON JUN 29 2015 .SYNOPSIS... A WARM AND HUMID AIR MASS WILL OCCUR ACROSS THE AREA THROUGH THE WEEK AS A HIGH PRESSURE REMAINS ANCHORED OVER THE GREAT BASIN. SOUTHEAST FLOW ALOFT WILL BRING ENOUGH MOISTURE AND UNSTABLE AIR TO CREATE A SLIGHT CHANCE OF THUNDERSTORMS AND SHOWERS THIS WEEK...MAINLY IN THE MOUNTAINS AND DESERTS. A COOLING TREND WILL OCCUR FOR THE END OF THE WEEK AS A LOW PRESSURE APPROACHES. && .UPDATE... HIGH PRESSURE REMAINS CENTERED OVER THE GREAT BASIN THIS MORNING. SOUTHEAST FLOW ALOFT CONTINUES TO PUMP MAINLY MIDDLE AND HIGH LEVEL MOISTURE ACROSS THE AREA TODAY. A FEW SHOWERS ARE MOVING NORTH ACROSS SOUTHERN CALIFORNIA ASSOCIATED WITH A WAVE OVER BAJA CALIFORNIA. MODEL SOLUTIONS ARE OFFERING UP A MIXED BAG OF VARYING IDEAS OF HOW TO HANDLE THE INSTABILITY WITH THE WAVE...BUT MOST MODEL BRING THE KINK IN THE MIDDLE LEVEL WINDS OVER THE AREA LATER THIS AFTERNOON AND THIS EVENING. RAP AND HRRR SOLUTIONS SEEMS TO BE TAKING A MORE AGGRESSIVE STANCE IN DEVELOPING NEGATIVE LIFTED INDICES AND K INDEX VALUES GREATER THAN 30 MOVING OVER SOUTHERN AND EASTERN LOS ANGELES COUNTY THIS AFTERNOON AND EVENING. WHILE THE PREVIOUS SHIFT REMOVED POPS FOR THE LOS ANGELES COUNTY VALLEYS AND COAST...ISOLATED SHOWERS CANNOT BE RULED OUT FOR THE SAN GABRIEL VALLEY AND LOS ANGELES COUNTY COAST. POPS WERE ADDED BACK FOR THIS AFTERNOON. WITH THE RIDGE IN PLACE ALOFT...A VERY WARM AND HUMID DAY IS SHAPING UP FOR TODAY. THE AREA IS GETTING OFF TO A WARMER START TODAY...BUT MIDDLE AND HIGH LEVEL CLOUDINESS SHOULD CUT INTO TEMPERATURES LATER AS THE WAVE PUSHES NORTH. LOCAL HEAT INDEX VALUES MAY APPROACH CRITICAL VALUES...ESPECIALLY IN LOCATIONS LIKELY CARRIZO AND ACTON THIS AFTERNOON. 950 MB TEMPERATURES LOOK WARMEST TODAY THEN START TO COOL LATER THIS WEEK. STRATUS COVERAGE WILL BE MINIMAL THE NEXT SEVERAL DAYS AS NAM BUFR TIME HEIGHT SECTIONS HAVE LITTLE HUMIDITY IN THE MARINE LAYER. LOCAL 2-KM WRF SOLUTIONS CONTINUE TO MODEL THE STRATUS EXCELLENTLY...AND SUGGEST NO COVERAGE ACROSS THE AREA TONIGHT. && .PREV DISCUSSION... SHORT TERM...NOT MUCH IN THE WAY OF MARINE STRATUS AS ALL OF THE MID AND HIGH LEVEL CLOUDS HAVE REALLY MESSED WITH THE MARINE INVERSION. THE BEST CHC OF LOW CLOUDS WILL BE ACROSS THE CENTRAL COAST. WITH 592 DM HGTS OVERHEAD AND ONLY VERY WEAK ONSHORE FLOW MAX TEMPS WILL BE WELL ABOVE NORMAL EACH DAY ACROSS THE ENTIRE AREA. HUMIDITY WILL BE ABOVE NORMAL AS WELL SO IT WILL ACTUALLY FEEL A LITTLE WORSE THAN IT ACTUALLY IS. INCREASING ONSHORE FLOW WILL BRING A LITTLE COOLING TO THE COASTS AND LOWER VLYS WEDNESDAY. THAT SAID MAX TEMPS ARE RIPE FOR SOME PRETTY BIG BUSTS DUE TO THE HIGH CLOUD FORECAST. LESS CLOUDS THAN FORECAST WILL RESULT IN WARMER THAN FORECAST HIGHS (LIKE SUNDAY) AND VICE VERSA (LIKE SATURDAY) .LONG TERM...NOT MUCH CHANGE THURSDAY THROUGH SATURDAY. THE UPPER HIGH MOVES FROM UTAH TO NEVADA. SKIES SHOULD BE MORE ON THE PARTLY CLOUDY SIDE. THIS WILL ALLOW BETTER INSTABILITY TO DEVELOP OVER THE MTNS. THE MOISTURE SHOULD DIMINISH A LITTLE BUT NOT ENOUGH TO ELIMINATE THE SLIGHT CHC OF AFT AND EVE MTN TSTMS. MAX TEMPS WILL BE RATHER SIMILAR EACH DAY AND WILL REMAIN SLIGHTLY ABOVE NORMAL. ON SUNDAY THE HIGH SHIFTS AWAY TO THE EAST AND A STRONGER UPPER LOW MOVES INTO THE EAST PAC AND SETS UP DRIER SW FLOW OVER THE AREA. THIS SHOULD KILL ANY CHC FOR AFTERNOON TSTMS. HGTS FALL AND THIS WILL BRING A FEW DEGREES OF COOLING. && .AVIATION...29/06Z. AT 08Z AT KLAX... THE INVERSION WAS 2000 FEET DEEP AND THE INVERSION TOP IS AT 2500 FEET WITH A TEMPERATURE OF 28 DEGREES CELSIUS. OVERALL...MODERATE CONFIDENCE IN THE 12Z TAFS. FOR LOCATIONS NORTH OF POINT CONCEPTION PATCHY VLIFR/LIFR/IFR CONDITIONS FOR THE CENTRAL COAST THROUGH 16Z. FOR LOCATIONS SOUTH OF POINT CONCEPTION... VFR CONDITIONS WILL PREVAIL THOUGH THERE IS A TWENTY PERCENT CHANCE OF LIFR/IFR CONDITIONS AT COASTAL LOCATIONS THROUGH 16Z. KLAX...MODERATE CONFIDENCE IN THE 12Z TAF. VFR CONDITIONS WILL PREVAIL THOUGH THERE IS A TWENTY PERCENT CHANCE OF LIFR/IFR CONDITIONS THROUGH 15Z. KBUR...MODERATE TO HIGH CONFIDENCE IN THE 12Z TAF. VFR CONDITIONS WILL PREVAIL THROUGHOUT THE FORECAST PERIOD. && .MARINE...29/900 AM. SMALL CRAFT ADVISORY CONDITIONS WILL LIKELY END SOUTH OF SAN MIGUEL ISLAND THIS AFTERNOON AND CONTINUE NORTH TO PIEDRAS BLANCAS EXCLUDING THE AREA FROM POINT SAL NORTH 0-10 NM THROUGH LATE TONIGHT. OTHERWISE THERE IS A CHANCE SHOWERS WILL DEVELOP NEAR SHORE SOUTH OF POINT MUGU THIS AFTERNOON. THROUGH EARLY WEDNESDAY TWO STORM SYSTEMS WITH GALE TO STORM FORCE WINDS AND WITH A FETCH BETWEEN 200-220 DEGREES RELATIVE TO VENTURA COAST WILL GENERATE SEAS 30-40 FEET SOUTHEAST OF NEW ZEALAND. THE SWELLS WILL BEGIN TO ARRIVE A WEEK FROM TODAY AND BUILD THROUGH TUESDAY. && .LOX WATCHES/WARNINGS/ADVISORIES... SMALL CRAFT ADVISORY (SEE LAXMWWLOX). && $$ PUBLIC...HALL/RORKE AVIATION...KJ MARINE...30 SYNOPSIS...HALL/SETO WWW.WEATHER.GOV/LOSANGELES
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
922 AM PDT MON JUN 29 2015 .SYNOPSIS... AN UPPER LEVEL DISTURBANCE MOVING THROUGH THE REGION FROM THE EAST WILL PRODUCE CLOUDS WITH SOME SPRINKLES TO THE FORECAST AREA THROUGH THIS AFTERNOON. HIGH PRESSURE OVER THE GREAT BASIN AND LOW PRESSURE OFF THE CALIFORNIA AND BAJA COASTS WILL CONTINUE TO DIRECT A FLOW OF MID AND HIGH LEVEL MONSOONAL MOISTURE ACROSS SOUTHERN CALIFORNIA FOR MUCH OF THE WEEK. THIS WILL SUPPORT A CHANCE OF THUNDERSTORMS THROUGH FRIDAY MAINLY NEAR THE MOUNTAINS AND PORTIONS OF THE DESERTS DURING THE AFTERNOON AND EARLY EVENING HOURS. SLOW DRYING IS POSSIBLE THIS WEEKEND. TEMPERATURES WILL BE ABOVE AVERAGE THROUGH WEDNESDAY...THEN COOL TO NEAR TO SLIGHTLY BELOW AVERAGE FOR THURSDAY THROUGH THE WEEKEND AS HIGH PRESSURE ALOFT WEAKENS. A SHALLOW MARINE LAYER AND WEAK ONSHORE FLOW WILL BRING PATCHY NIGHT AND MORNING LOW CLOUDS AND FOG NEAR THE COAST AND WESTERN VALLEYS AT TIMES. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... MORNING VISIBLE SATELLITE SHOWS AREAS OF MID AND HIGH LEVEL CLOUDS MOVING OVER THE REGION FROM THE EAST-SOUTHEAST...WITH RADAR INDICATING SOME EMBEDDED LIGHT SHOWERS/SPRINKLES. HAVE NOT RECEIVED ANY REPORTS OF MEASURABLE RAINFALL OVER THE PAST 12 HOURS FROM THESE ECHOES...SO MOST OF THEM ARE LIKELY JUST SPRINKLES/VIRGA DUE TO THE CONTINUED DRY LOWER LAYER OF THE ATMOSPHERE. THIS DRY LAYER IS INDICATED WELL ON THE 12Z MIRAMAR SOUNDING...WITH MOST OF THE MOISTURE LOCATED ABOVE 600 MB ALL THE WAY TO THE TROPOPAUSE. MEANWHILE...A NEAR SURFACE MARINE LAYER INVERSION IS ALSO SHOWN...BUT ONLY A FEW PATCHES OF STRATUS WERE ABLE TO FORM ALONG THE COAST THIS MORNING DUE TO INTERFERENCE FROM ALL THE MID AND UPPER LEVEL MOISTURE. THIS LOW STRATUS SHOULD CLEAR OUT BY LATE MORNING. ON WATER VAPOR SATELLITE...A RIDGE CAN BE SEEN OVER THE GREAT BASIN...WITH A LOW FAR SOUTHWEST OF LOS ANGELES. THIS POSITIONING OF THE RIDGE AND TROUGH IS RESULTING IN THE MOIST SOUTHEAST FLOW OVER THE REGION TODAY. THE AREAS OF MID AND UPPER LEVEL CLOUDS...SHOWERS AND SPRINKLES MOVING THROUGH THIS MORNING ARE ASSOCIATED WITH AN UPPER LEVEL WAVE ROTATING AROUND THE RIDGE. 14Z HRRR INDICATES THAT ISOLATED-TO-SCATTERED SPRINKLES WILL CONTINUE THROUGH THE MORNING...WITH LARGER AREAS OF SPRINKLES/LIGHT SHOWERS MOVING THROUGH THE AREA THIS AFTERNOON. AFTERNOON/EARLY EVENING THUNDERSTORM CHANCES FOR THE MOUNTAINS AND PORTIONS OF THE DESERTS DO NOT LOOK TOO GREAT...DUE TO A COMBINATION OF THE MOISTURE BEING A BIT TOO ELEVATED IN TERMS OF ITS HEIGHT...AND A LITTLE BIT TOO MUCH CLOUD COVER...WHICH LIMITS HOW MUCH INSTABILITY DEVELOPS FROM DAY- TIME HEATING. THE ONLY HI-RES MODEL THAT SHOWS MUCH CONVECTIVE DEVELOPMENT OVER THE MOUNTAINS THIS AFTERNOON IS THE 00Z CANSAC-WRF. LOOK FOR TEMPERATURES TODAY TO BE OVERALL SIMILAR TO YESTERDAY. IT APPEARS THAT THERE WILL BE BETTER INSTABILITY ON TUESDAY AND WEDNESDAY WITH LESS CLOUD COVER AND STILL A DECENT AMOUNT OF MOISTURE IN THE FORM OF 1.3-1.6 INCHES OF PRECIPITABLE WATER. HOWEVER...IT STILL LOOKS LIKE MOST OF THE MOISTURE WILL BE CONFINED ABOVE 600 MB. NEVERTHELESS...CHANCES FOR AFTERNOON THUNDERSTORMS/SHOWERS OVER THE MOUNTAINS AND DESERTS WILL CONTINUE FOR TUESDAY AND WEDNESDAY...AND ALSO INTO THURSDAY AND FRIDAY...AS THE RIDGE OVER THE GREAT BASIN REMAINS IN PLACE...RESULTING IN CONTINUED MOIST SOUTHEASTERLY FLOW. STILL...MOST OF THIS MOISTURE STAYS ABOVE 600 MB...SO NO HUGE THUNDERSTORM OUTBREAKS ARE EXPECTED. THE MODELS ARE ALSO HINTING AT AN EASTERLY WAVE AND ASSOCIATED MOISTURE/INSTABILITY MOVING OVER SOUTHERN CALIFORNIA FROM THE EAST WEDNESDAY NIGHT INTO THURSDAY MORNING WHICH COULD BRING NOCTURNAL ELEVATED SHOWERS AND THUNDERSTORMS TO ALL AREAS. IN FACT...THE NAM12 PRECIPITATION OUTPUT SHOWS SCATTERED PRECIPITATION OVER THE FORECAST AREA DURING THAT TIME. MAY NEED TO EXPAND THE CHANCES FOR SHOWERS/THUNDERSTORMS FOR THAT TIME-PERIOD. AS FAR AS TEMPERATURES GO...SOME WARMING IS LIKELY TUESDAY...WITH DAY-TIME HIGHS CONTINUING AT 5-10 DEGREES ABOVE NORMAL ON WEDNESDAY...DUE TO OVERALL LESS CLOUDS AND STRONGER HIGH PRESSURE ALOFT. WITH THE RIDGE WEAKENING THURSDAY AND FRIDAY...EXPECT COOLING WITH TEMPERATURES FALLING TO NEAR TO SLIGHTLY BELOW NORMAL. THINGS COULD START DRYING OUT AS EARLY AS SATURDAY...AS THE ECMWF MOVES THE RIDGE TO THE EAST AND BRINGS SOUTHERLY FLOW DURING THE WEEKEND...AND THEN SOUTHWESTERLY FLOW EARLY NEXT WEEK...WITH MOST OF THE MOISTURE STAYING TO OUR EAST. MEANWHILE...THE GFS CONTINUES TO KEEP THE RIDGE OVER THE GREAT BASIN ON SATURDAY...AND IT ISNT UNTIL LATE SUNDAY THAT THE RIDGE MOVES OVER THE FOUR CORNERS REGION. HOWEVER...IT DOES NOT KICK IN THE DRY SOUTHWESTERLY FLOW ALOFT UNTIL NEXT MONDAY. THE COOLING CONDITIONS MAY CONTINUE INTO THE WEEKEND...WITH GRADUAL WEAKENING OF THE RIDGE. LOOK FOR THE PATCHY NIGHT AND MORNING MARINE LAYER STRATUS TO CONTINUE OVER THE COASTAL AND WESTERN VALLEYS THROUGH THE FORECAST PERIOD. && .AVIATION... 291520Z...COAST/VALLEYS...MAINLY BKN CLOUDS AOA 10000 FT MSL AND ISOLATED LIGHT SHOWERS. VERY PATCHY STRATUS EXTENDING ABOUT 5-10 MILES INLAND...AND FROM ABOUT KCRQ SOUTHWARD...WITH BASES NEAR 800 FT MSL AND TOPS 1200 FEET MSL. STRATUS DISSIPATING AROUND 1630Z. PATCHY STRATUS REDEVELOPING LATE TONIGHT/EARLY TUE MORNING WITH SIMILAR BASES AND TOPS...BUT AGAIN CONFIDENCE IN TIMING/OCCURRENCE IS LOW. RISK OF BKN LOW CLOUDS AT KSNA IS STILL VERY LOW...SO WILL LEAVE IT OUT OF THE KSNA TAF. MTNS/DESERTS...SCT-BKN CLOUDS AOA 10000 FT MSL WILL CONTINUE THROUGH THE MORNING. CU/TCU DEVELOPING THIS AFTERNOON WITH A SLIGHT CHANCE OF SHOWERS/THUNDERSTORMS THROUGH THE EVENING. THUNDERSTORM TOPS TO NEAR 30000 FT MSL...LOCAL GUSTY SURFACE WINDS...AND LOCAL VIS RESTRICTIONS IN HEAVY RAIN POSSIBLE. && .MARINE... 825 AM...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH FRIDAY. && .SKYWARN... SKYWARN ACTIVATION IS UNLIKELY FOR TODAY. WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE...SMALL
AREA FORECAST DISCUSSION
NWS MIAMI FL
338 PM EDT MON JUN 29 2015 .DISCUSSION... A BROAD TROUGH CONTINUES TO SIT OVER THE SOUTHEAST UNITED STATES. THIS IS HELPING TO KEEP SOME ADDITIONAL INSTABILITY OVER THE AREA. FOR THIS EVENING, A 500 MB SHORT WAVE IS MOVING ACROSS THE AREA. THIS HAS AIDED IN A LARGE AREA OF SHOWERS AND THUNDERSTORMS TO DEVELOP IN THE LAKE REGION. THE HRRR SHOWS THIS AREA FORMING INTO A LINE F THUNDERSTORMS OVER PALM BEACH COUNTY THIS EVENING, BEFORE EXITING OVER THE COASTAL WATERS TO THE EAST. FOR TONIGHT, MODELS ARE SHOWING MOST OF ANY CONVECTIVE ACTIVITY WILL BE OVER THE ATLANTIC COASTAL WATERS. THE SHORT WAVE WILL CONTINUE TO EXIT TO THE NORTHEAST THROUGH TOMORROW MORNING. FOR TOMORROW, A SURFACE HIGH TO THE WEST VERY SLOWLY BEGINS TO BUILD BACK IN OVER SOUTH FLORIDA. MODELS LAST WEEK WERE SHOWING THIS WAS SUPPOSED TO OCCUR BY TOMORROW, BUT NOW IT LOOKS AS THOUGH IT WILL SLOWLY BUILD, WHICH WILL TURN THE WIND TO THE SOUTHEAST BY WEDNESDAY AND EAST BY FRIDAY. BECAUSE OF THIS, SHOWERS AND THUNDERSTORMS WILL BE ABLE TO CONTINUE TO AFFECT MUCH OF THE INTERIOR AND LAKE REGION TOMORROW. BY WEDNESDAY, THE TURN TO THE SOUTHEAST WILL SHIFT THE FOCUS OF STORMS MORE TOWARDS THE WESTERN INTERIOR, ALTHOUGH THERE WILL CONTINUE TO BE A CHANCE FOR STORMS OVER THE EAST COAST OF SOUTH FLORIDA WEDNESDAY AFTERNOON, AND EVEN THURSDAY AFTERNOON, ALTHOUGH THE CHANCES DO SLIGHTLY DIMINISH ON THURSDAY FOR THE SOUTHEAST COAST. BY FRIDAY, THE HIGH WILL BE STRONG ENOUGH AND POSITIONED RIGHT FOR THE WIND TO TURN TO THE EAST. THIS WILL SHIFT THE MAIN FOCUS OF SHOWERS AND THUNDERSTORMS TO THE WESTERN INTERIOR AND GULF COAST THROUGH THE BEGINNING OF NEXT WEEK. && .AVIATION... LOCAL MODELS INCREASINGLY SUGGESTING THAT SCATTERED/NUMEROUS CONVECTION WILL SPREAD ESE TOWARD ATLANTIC TERMINALS LATE THIS AFTERNOON. BEST CHANCE WILL BE KPBI...BUT WILL LEAVE ALL EAST COAST SITES WITH VCTS 19-0Z. ALSO MONITORING FOR TSTMS TO DVLP ALONG SEA BREEZE...LOW CONFIDENCE IN THIS...BUT WITH BOUNDARY EXPECTED TO REMAIN FAIRLY CLOSE TO THE COAST...ANY INITIATION WOULD LIKE BE IN VICINITY OF TERMINALS. ACTIVITY WANES BY AT LEAST 2Z...THEN DRY FORECAST. EXPECT SW WINDS TO TURN SSE FOR EASTERN TERMINALS BY 20Z...THEN LIGHT/CALM WINDS OVERNIGHT. && .MARINE... HIGH PRESSURE TO THE WEST WILL KEEP THE WIND SOUTH THIS EVENING AND THEN SLOWLY BUILD OVER THE NEXT FEW DAYS. THIS WILL TURN THE WIND TO THE SOUTHEAST TOMORROW THROUGH THURSDAY. BY FRIDAY, THE WIND WILL TURN TO THE EAST THROUGH THE BEGINNING OF NEXT WEEK. THIS WILL ALLOW FOR A SLOWLY INCREASING THREAT OF RIP CURRENTS ALONG THE ATLANTIC BEACHES INTO NEXT WEEK. THERE WILL BE CONTINUED CHANCES OF SHOWERS AND THUNDERSTORMS ACROSS THE SOUTH FLORIDA COASTAL WATERS THROUGH THE WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 76 93 78 92 / 30 30 30 40 FORT LAUDERDALE 78 91 80 90 / 20 20 20 40 MIAMI 77 92 80 91 / 20 30 20 30 NAPLES 76 93 77 93 / 10 20 10 40 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....13/SI AVIATION...23/SK
AREA FORECAST DISCUSSION
NWS NORTHERN INDIANA
137 PM EDT MON JUN 29 2015 .SYNOPSIS... ISSUED AT 135 PM EDT MON JUN 29 2015 SCATTERED SHOWERS AND AN ISOLATED THUNDERSTORM REMAIN POSSIBLE THIS AFTERNOON BEFORE A BRIEF DRY PERIOD OVERNIGHT. PATCHY FOG MAY FORM TOWARD DAYBREAK...ESPECIALLY IN AREAS THAT RECEIVED RAIN TODAY. THERE IS ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS ON TUESDAY AS AN UPPER LEVEL SYSTEM ROTATES ACROSS THE REGION. HIGHS THIS AFTERNOON WILL RANGE FROM THE UPPER 60S TO LOWER 70S WHILE LOWS TONIGHT DROP INTO THE UPPER 50S AND LOWER 60S. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 446 AM EDT MON JUN 29 2015 THE TRAIN OF WAVES CONTINUES WITH ONE UPPER LEVEL SYSTEM NOW PASSING ACROSS THE SOUTHERN GREAT LAKES/N OHIO VALLEY WITH SCATTERED TO NUMEROUS SHOWERS AND A FEW STORMS. COVERAGE SO FAR HAS STRUGGLED ACROSS THE FORECAST AREA WITH SOME SMALL AREAS OF SHOWERS MOVING GENERALLY ALONG AND SOUTH OF US 24. TRENDS TO THE WEST WOULD SUGGEST THAT RAINFALL CHANCES MAY DIMINISH QUICKLY THIS MORNING WITH THE MAIN FOCUS ON SE/E SECTIONS THAT HAVE SEEN TOO MUCH RAIN ALREADY. A FEW OF THE HIGH RES MODELS PRINT OUT THREE QUARTERS TO OVER AN INCH OF RAIN (6Z RAP WENT TO EXTREME OF SWATH OF 1 TO 2 INCHES OF RAIN FROM GRANT COUNTY NE TO FT WAYNE). GIVEN LIKELIHOOD OF DEFORMATION ZONE OF MODERATE TO POSSIBLY LOCALLY HEAVY RAINFALL SETTING UP IN EASTERN AREAS...RAINFALL AMOUNTS COULD BE REALIZED. HOWEVER...PWATS NOT AS HIGH AS PAST SYSTEMS AND WHILE BRIEFLY SLOWING THE SYSTEM WILL BE SOMEWHAT MORE PROGRESSIVE IN NATURE. WITH MUCH OF THE AREA OF CONCERN ALREADY COVERED BY AREAL FLOOD WARNING THAT WILL LIKELY BE EXTENDED HOISTING A WATCH FOR THOSE AREAS SERVES NO PURPOSE. IN LOCATIONS FURTHER SOUTHWEST...ARGUMENT COULD BE MADE TO HOIST THE WATCH...BUT EQUAL ARGUMENT (AND MAYBE BETTER APPROACH) COULD BE TO EXPAND/ISSUE AREAL FLOOD WARNING VS A FLOOD WATCH. WILL MONITOR TRENDS NEXT COUPLE OF HOURS. TEMPERATURES WERE LOWERED SOMEWHAT TODAY WITH CLOUDS AND PRECIP BUT MAY STILL BE TOO WARM. BEST POTENTIAL FOR HEATING MAY BE IN SW AREAS THAT COULD SEE SOME BREAKS IN THE CLOUDS BY LATE AFTERNOON AS THE SFC LOW PASSES OVERHEAD. PRECIP MAY LINGER IN THE EAST INTO THE EVENING BUT SHOULD PUSH OUT RATHER QUICKLY AS SMALL AREA OF SUBSIDENCE SHIFTS IN LATE EVENING INTO PART OF THE OVERNIGHT HOURS BEFORE THE NEXT WAVE APPROACHES. KEPT SLGT CHC POPS THROUGH THE NIGHT WITH INCREASE IN THE WEST TOWARDS DAYBREAK. LOWS WILL DROP INTO THE UPPER 50S TO LOWER 60S. && .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 446 AM EDT MON JUN 29 2015 SHRTWV OVER MANITOBA THIS MORNING EXPECTED TO DROP SE TO NE IL BY 12Z TUE THEN SWING EAST THROUGH BASE OF TROF ACROSS NRN INDIANA DURING THE DAY. MODELS SUGGEST FAIRLY STRONG FORCING AND WK-MOD INSTABILITY WILL ACCOMPANY THIS SYSTEM TUE...SO SCT-NUMEROUS SHOWERS/TSTMS LIKELY. SFC CDFNT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO MOVE SLOWLY SE ACROSS OUR CWA TUE NGT-WED NGT AS ANOTHER SHRTWV MOVES SE FROM THE NRN PLAINS TO THE LWR OH VALLEY. THIS MAY CAUSE SCT SHOWERS/TSTMS TO CONT IN THE CWA WITH BEST CHANCES ACROSS SRN PORTIONS OF THE AREA IN CLOSEST PROXIMITY TO THE SLOW MOVG SFC BOUNDARY. CURRENT AMPLIFIED UPR AIR PATTERN WITH STRONG RIDGE IN WRN NORTH AMERICA AND TROF FROM HUDSON BAY THROUGH THE GRTLKS EXPECTED TO TRANSITION TO A MORE ZONAL FLOW LATE IN THE PERIOD AS GULF OF ALASKA CLOSED LOW GETS KICKED EAST INTO WRN CANADA WKNG RIDGE IN THAT AREA. STILL... A WK BROAD TROF EXPECTED TO PERSIST ACROSS THE GRTLKS THROUGH THE PERIOD WITH AN E-W ORIENTED STNRY SFC BOUNDARY LIKELY CONTG JUST SOUTH OF OUR CWA. ALSO APPEARS THAT SOME WK SHRTWVS WILL TOP WRN RIDGE AND MOVE SE TOWARD BASE OF THE BROAD TROF OVER OUR AREA IN THIS TIMEFRAME. THUS... A SMALL CHANCE OF SHOWERS/TSTMS CONTS FOR MUCH OF THE LONG TERM PERIOD. THIS SCENARIO ALSO SUPPORTS A CONTINUATION OF TEMPS SLIGHTLY BLO NORMAL THROUGH THIS PERIOD... THOUGH A WARMUP EXPECTED NEXT WEEKEND AS FLOW ALOFT BECOMES MORE ZONAL AND LOW LEVEL SOUTHERLY WINDS RETURN. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 131 PM EDT MON JUN 29 2015 UPPER LEVEL TROUGH KEEPING AREA OF DEFORMATION RAINFALL GOING NEAR KSBN EARLY THIS AFTERNOON BUT SHOULD BE DRIFTING EAST OF TERMINAL SHORTLY. OTHERWISE AN OCCASIONAL SHOWER IS POSSIBLE THROUGH EARLY EVENING WITH DIFFICULTY IN TIMING ANY SPECIFIC EVENT AT TERMINALS. PATCHY FOG OVERNIGHT WITH MOIST CONDITIONS AND LIGHT WINDS. CLOUD COVER WILL DICTATE HOW WIDESPREAD FOG BECOMES BUT EXPECTING PARTLY CLOUDY SKIES TO LIMIT RADIATIONAL COOLING. ANOTHER SHORT WAVE DROPS IN TUESDAY MORNING INTO EARLY AFTERNOON WITH ANOTHER CHANCE FOR SHOWERS AND A THUNDERSTORM. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...FISHER SHORT TERM...FISHER LONG TERM...JT AVIATION...LASHLEY VISIT US AT WWW.WEATHER.GOV/IWX (ALL LOWER CASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSNORTHERNINDIANA WWW.TWITTER.COM/NWSIWX WWW.YOUTUBE.COM/NWSNORTHERNINDIANA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
332 PM CDT MON JUN 29 2015 .SYNOPSIS... ISSUED AT 330 PM CDT MON JUN 29 2015 12Z UA ANALYSIS HAS AN INFERRED 850MB LOW NEAR KGYY WITH A TROF EXTENDING INTO THE LOWER MISSISSIPPI VALLEY. A NICE VORT MAX WAS APPROACHING THE INTERNATIONAL BORDER IN MANITOBA WHILE AN UPPER LEVEL RIDGE WAS OVER THE ROCKIES. SATELLITE/RADAR DATA THROUGH MID AFTERNOON SHOWS DIURNAL CONVECTION DEVELOPING ACROSS THE AREA WITH A MORE SUBSTANTIAL CONVECTIVE COMPLEX ACROSS NORTHERN WISCONSIN. 18Z SFC DATA HAS A WEAK TROF MOVING THROUGH EASTERN IOWA WITH A WEAK LOW OVER WESTERN INDIANA. DEW POINTS WERE IN THE 60S ACROSS THE WESTERN GREAT LAKES INTO THE PLAINS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 330 PM CDT MON JUN 29 2015 ISOLATED TO SCATTERED SHOWERS AND SOME THUNDERSTORMS WILL BE SEEN ACROSS THE AREA THROUGH SUNSET. BRIEF DOWNPOURS ARE LIKELY FROM THE STRONGER STORMS ALONG WITH POSSIBLY SOME SMALL HAIL. AFTER SUNSET...THE DIURNAL CONVECTION WILL SLOWLY DISSIPATE BUT QUESTIONS THEN TURN TO THE THUNDERSTORM COMPLEX ACROSS NORTHERN WISCONSIN. TRENDS FROM THE RAP IS TO DEVELOP NEW CONVECTION IN WESTERN MINNESOTA AND HAVE IT EVOLVE INTO A LOOSE LINE AND MOVE THROUGH THE AREA OVERNIGHT. HOWEVER...SATELLITE TRENDS SHOW NO DIURNAL CLOUD DEVELOPMENT IN THIS AREA. ONE POSSIBLE REASON IS THAT SMOKE FROM THE FIRES IN ALASKA MAY HAVE SUPPRESSED TEMPERATURES. REGARDLESS...THE APPROACHING UPPER LEVEL DISTURBANCE SHOULD MAINTAIN THE THUNDERSTORM COMPLEX IN NORTHERN WISCONSIN AND POSSIBLY ALLOW NEW DEVELOPMENT INTO EASTERN MINNESOTA. IF THIS OCCURS...THEN A LOOSELY ORGANIZED LINE OF SHOWERS AND A FEW THUNDERSTORMS MAY SWEEP THROUGH THE AREA BETWEEN 10 PM AND 4 AM. RAIN CHANCES SHOULD BE ON THE DECREASE OVER THE NORTHWEST HALF OF THE AREA AFTER 4 AM. WINDS WILL BE LIGHT AT TIMES TONIGHT SO THERE IS A POTENTIAL FOR SOME PATCHY FOG TO DEVELOP IN SHELTERED LOW LYING AREAS. ON TUESDAY THE BETTER RAIN CHANCES WILL BE OVER THE SOUTHEAST HALF OF THE AREA. INTERESTINGLY...SEVERAL MODELS ARE SUGGESTING MUCH IF NOT ALL OF THE AREA COULD BE DRY ON TUESDAY. THIS TREND WILL HAVE TO BE WATCHED TO SEE IF A DRY DAY COULD BE SEEN ACROSS THE AREA. ..08.. .LONG TERM...(TUESDAY NIGHT THROUGH NEXT MONDAY) ISSUED AT 330 PM CDT MON JUN 29 2015 TUESDAY NIGHT THROUGH FRIDAY...LATEST MREF OUTPUT SUGGESTS PATTERN DE-AMPLIFICATION STARTS TO TAKE PLACE THIS PERIOD ACRS THE CONUS... BUT BROADENING NORTHWESTERLIES ALOFT STILL WILL LOOK TO SHUTTLE A WAVE DOWN ACRS THE PLAINS AND LOW TO MID MS RVR VALLEY TUE NIGHT INTO WED. INTERESTING THAT BULK OF THE 12Z RUN MEDIUM RANGE SOLUTIONS HAVE TRENDED WEST AND SOUTH WITH ELEVATED FORCING WING THAT WOULD PRODUCE A SHIELD OF OVERRUNNING PRECIP/MCS-TYPE FEATURE ALONG AND JUST OVER LOWER LEVEL BAROCLINIC RIBBON LATE TUE NIGHT INTO WED. SO MUCH SO THAT THE SOUTHWESTERN THIRD OF THE CWA JUST GETS CLIPPED BY THIS SYSTEM WITH SECONDARY RAINS OF A QUARTER OF AN INCH TO A HALF INCH BY WED AFTERNOON...WHILE THE HEAVY RAINS FALL ACRS SOUTHWESTERN IA INTO EAST CENTRAL MO. WILL START TO TREND THIS WAY IN THE FCST GRIDS WITH THE MODEL CONSENSUS MAKING FOR SOME CONFIDENCE. CLOUD COVER ODD THE SYSTEM AS WELL AS LIGHTER RAIN IN THE SOUTHWEST WILL KEEP A LID ON TEMPS IN THE MID 70S TO NEAR 80 ON WED. THE 12Z RUN GFS IS THEN MORE BULLISH ON WESTWARD EXTENSION AND STRENGTH OF LLVL RIDGE COMPLEX JUTTING OUT WESTWARD FROM THE GRT LKS TO THE UPPER MS RVR VALLEY...ENOUGH SO THAT IT MAINTAINS A DRY AND BELOW NORMAL TEMP FCST THROUGH FRI NIGHT. THIS IN CONTRAST WITH THE NEW 12Z RUN ECMWF WHICH STILL DIGS A SECONDARY SHORT WAVE DOWN ACRS THE UPPER MIDWEST WITH ENOUGH ELEVATED THTA-E DRAW TO PRODUCE SCTRD SHOWERS AND A FEW STORMS ACRS THE REGION THU NIGHT INTO FRI. FOR NOW WILL GO DRY FOR THU...BUT THROW A NOD TO THE EURO WITH POPS THU NIGHT INTO FRI. IF THE GFS IS RIGHT WITH NO PRECIP...WITH CLEAR SKIES TEMPS WILL DIP WELL DOWN INTO THE 50S IN MOST OF THE AREA BY FRI MORNING WITH FOG POSSIBLE. SATURDAY THROUGH NEXT MONDAY...LONGER RANGE INDICATIONS AND HANDLING THE PATTERN TRANSITION TO A MORE FLATTENED WESTERLY REGIME AND MAIN UPPER JET STREAK MIGRATION TO SOUTHERN CANADA MAKE FOR SOME UNCERTAINTY FOR THE UPCOMING HOLIDAY WEEKEND. BUT BOTH THE GFS AND ECMWF ARE MAINLY DRY FOR MOST OF THE AREA SAT INTO SAT NIGHT. THE GFS HANGS UP A BOUNDARY ACRS NORTHERN MO WHICH MAY ALLOW FOR SOME DIURNALLY INDUCED ISOLATED TO SCTRD SHOWERS IN THE SOUTHERN CWA BY LATE SAT AFTERNOON AND EVENING. THE EURO HAS LESS FOCUS BUT STILL DEVELOPS POP-UP ISOLATED TO SCTRD SHOWERS/STORMS ACRS MOST OF THE CWA/EXCEPT NW IL/ IN THE AFTERNOON BUOYANCY THAT BUILDS UP. MAY KEEP THE FCST MAINLY DRY FOR NOW...HIGHS STILL A BIT BELOW NORMAL IN THE UPPER 70S TO LOWER 80S. MORE PROGRESSIVE PATTERN WILL THEN LOOK TO USHER A STRONGER WAVE ACRS THE U.S./CANADIAN BORDER REGION AND INTO THE UPPER MIDWEST SOMETIME FROM LATE SUNDAY INTO NEXT MONDAY. THE MEDIUM RANGE SOLUTIONS VARY IN TIMING AND EXTENT OF SOUTHERLY DIG BY THIS FEATURE. FOR NOW WILL BUILD POPS BACK UP FOR SUNDAY NIGHT INTO MONDAY...WITH PRE-SYSTEM WARM DRAW HELPING TEMPS GET BACK TO MORE NORMAL LEVELS EARLIER IN THE DAY SUNDAY. ..12.. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1235 PM CDT MON JUN 29 2015 LOCALIZED MVFR CONDITIONS AT KBRL WILL GIVE WAY TO VFR CONDITIONS BY 20Z/29. OTHERWISE EXPECT VFR CONDITIONS THROUGH 06Z/30 WITH ISOLATED TO SCATTERED SHRA/TSRA DEVELOPING DURING PEAK HEATING. IF A SHRA/TSRA AFFECTS A TAF SITE THEN A BRIEF PERIOD OF MVFR/IFR CONDITIONS IS POSSIBLE. AFT 06Z/30 VFR CONDITIONS ARE EXPECTED TO CONTINUE. HOWEVER...WET GROUND AND LIGHT WINDS MAY ALLOW PATCHY MVFR/IFR CONDITIONS IN FOG TO DEVELOP PRIOR TO SUNRISE TUESDAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...08 SHORT TERM...08 LONG TERM...12 AVIATION...08
AREA FORECAST DISCUSSION
NWS DES MOINES IA
254 PM CDT MON JUN 29 2015 .SHORT TERM /TONIGHT/... ISSUED AT 254 PM CDT MON JUN 29 2015 MAIN CHALLENGE TONIGHT WILL BE EXTENT OF CONVECTION THIS EVENING. SYNOPTIC MODELS SHOWING COLD FRONT ENTERING THE FAR NORTH BY 00Z WITH FRONT HEADING TO SOUTHEAST IOWA BY 12Z TUESDAY. BEST FORCING FOCUSED OVER THE EASTERN/NORTHEAST PORTION OF THE FORECAST AREA THIS EVENING. MESOSCALE MODELS SUPPORT THIS AS WELL WITH HRRR AND VARIOUS WRF SOLUTIONS SUGGESTING THAT BEST SFC MOISTURE CONVERGENCE WILL FOCUS OVER NORTHEAST SECTIONS FROM NEAR MASON CITY SOUTHEAST TOWARD OTTUMWA. CURRENT INSTABILITY REMAINS MODEST WITH MLCAPES BETWEEN 1500 AND 2000 J/KG OVER THE EAST THOUGH WITH LACK OF SFC TRIGGER...LITTLE THREAT FOR ANY CONVECTION UNTIL LATE AFTERNOON AND SHOULD REMAIN QUITE LIMITED...IF AT ALL...UNDER BOUNDARY GETS CLOSER OR OUTFLOWS FROM STORMS CAN FIRE CONVECTION DOWNSTREAM. WITH THE BETTER CHANCES FOR CONVECTION OVER THE EAST THIS EVENING...WILL BE NARROWING POPS/WX OVER THE FORECAST AREA. GIVEN THE DIURNAL SUPPORT NEEDED TO SUSTAIN CONVECTION...AM EXPECTING A LESSENING OF COVERAGE AFT 02Z WITH ISOLATED COVERAGE THROUGH MID TO LATE EVENING. SMOKE FROM SASKATCHEWAN FIRES IMPACTING SUNSHINE THIS AFTERNOON AND THICKER LAYER OF SMOKE LIKELY TO CONTINUE OVER IOWA SKIES TONIGHT. THIS SHOULD RESULT IN A BRILLIANT SUNSET FOR AREAS WITH LESSER CLOUD COVER. LOWS OVERNIGHT WILL COOL TO THE LOWER TO MID 60S OVER THE REGION. .LONG TERM /TUESDAY THROUGH MONDAY/... ISSUED AT 254 PM CDT MON JUN 29 2015 SOMEWHAT QUIET WEATHER PATTERN SETTING UP OVER CENTRAL IOWA THROUGHOUT THE WEEK AND INTO THE HOLIDAY WEEKEND. NORTHWEST FLOW ALOFT CONTINUES TO DOMINATE THE WEATHER PATTERN AND A FEW SHORTWAVES MOVE INTERMITTENTLY ACROSS THE FORECAST AREA THROUGH FRIDAY AND BRING SLIGHT TO LOW CHANCE POPS TUESDAY NIGHT INTO FRIDAY. TIMING AND LOCATION OF SHORTWAVES WAS THE MAIN CONCERN THROUGH THE EXTENDED PERIOD. OTHER CONCERN WAS TEMPS AND HOW THEY WILL BE AFFECTED BY THE SMOKE PLUME FROM CANADA. TUESDAY INTO FRIDAY...FIRST SHORTWAVE IS ANTICIPATED TO CUT ACROSS WESTERN IOWA LATE TUESDAY NIGHT INTO WEDNESDAY. SURFACE HIGH OVER THE GREAT LAKES LOOK TO BECOME MORE DOMINANT AND SHOULD HOLD OFF THE SHORTWAVE TO FURTHER SOUTH AND WEST. PLUS...THE SURFACE HIGH WILL ADVECT IN DRIER AIR INTO THE STATE THROUGHOUT THE WEEK. TRENDED TOWARD A DRIER FORECAST OVER CENTRAL TO NORTHEAST PORTIONS OF THE FORECAST AREA TUESDAY NIGHT INTO WEDNESDAY. ANOTHER SHORTWAVE MAKES A SIMILAR TRACK...MAYBE EVEN SHOVED FURTHER WEST BY THE SURFACE HIGH...THURSDAY NIGHT INTO FRIDAY. WENT CLOSE TO GUIDANCE FOR HIGH TEMPS TUESDAY BUT LOW CONFIDENCE IN HOW MUCH THE SMOKE FROM CANADA WILL AFFECT THE MAX TEMPS...ESPECIALLY SINCE DO NOT KNOW WHEN THE FIRES WILL CEASE. IF SMOKE IS STILL AROUND ON TUESDAY...THEN LIKELY NEED TO DROP A DEGREE OR TWO OFF THE CURRENT FORECAST. SATURDAY INTO MONDAY...SURFACE HIGH CONTINUES TO DOMINATE THE WEATHER PATTERN ON SATURDAY BEFORE A FAIRLY STRONG SHORTWAVE ATTEMPTS TO BREAK THROUGH BY SATURDAY NIGHT. HOWEVER...SYSTEM REMAINS MOISTURE STARVED AND THUS HAVE LOW POPS AND LOW CONFIDENCE WITH ANY WIDESPREAD PRECIP LATE IN THE WEEKEND. && .AVIATION...29/18Z ISSUED AT 1250 PM CDT MON JUN 29 2015 MAIN CONCERNS WILL BE COVERAGE AND TIMING OF CONVECTION. THOUGH UNSTABLE...LITTLE FORCING OR INITIATION MECHANISM CURRENTLY TO FORCE THUNDER THIS AFTERNOON. CU FIELD MAY SEE A FEW STRONGER UPDRAFTS AND -TSRA BETWEEN 20-23Z...BUT MAIN FORCING OF SYNOPTIC BOUNDARY OVER MN WILL BE THE BETTER TRIGGER TODAY...WITH SCT THUNDER MOVING SOUTH TOWARD IA/MN BORDER BETWEEN 22-00Z. SMOKE FROM FIRES IN SASKATCHEWAN CONTINUES TO DRIFT SOUTH OVER IOWA. THOUGH SFC OBSTRUCTIONS HAVE NOT BEEN OBSERVED...LAYER OF SMOKE MAY CAUSE SOME RESTRICTION ALOFT OR ON APPROACH GIVEN THE COVERAGE AND DEPTH. WINDS WILL REMAIN NEAR 10-12KT GUSTS 15 KTS THROUGH 00Z. AS DIURNAL HEATING WANES...CONVECTION WILL END AND CONDITIONS REMAIN QUIET THROUGH END OF PERIOD. /REV && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...REV LONG TERM...PODRAZIK AVIATION...REV
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1239 PM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 839 AM CDT MON JUN 29 2015 VISIBILITIES HAVE RAPIDLY IMPROVED OVER MUCH OF THE AREA SINCE 7 AM. MOST OF THE DENSE FOG ADVISORY HAS BEEN CANCELLED. THOSE AREAS THAT HAVE NOT BEEN CANCELLED WILL EXPIRE AT 9 AM. UPDATE ISSUED AT 424 AM CDT MON JUN 29 2015 LOOKING AT WEB CAMS AND OBSERVATION SITES HAS INDICATED THE FOG HAS WORSENED AND MANY LOCATIONS ARE SOCKED IN WITH VISIBILITIES OF 1/4 MILE OR LESS. THEREFORE...I HAVE ISSUED A DENSE FOG ADVISORY FOR THE ENTIRE CWA UNTIL 9 AM. IF THE FOG DISSIPATES SOONER THAN THE ADVISORY CAN BE CANCELLED. && .SYNOPSIS... ISSUED AT 345 AM CDT MON JUN 29 2015 LIGHT TO CALM WINDS AND WET GROUND HAS LED TO THE DEVELOPMENT OF GROUND FOG ACROSS MUCH OF THE CWA. LOOKING AT WEB CAMS AND OBSERVATIONS THE VISIBILITIES WERE HIGHLY VARIABLE AND A SPECIAL WEATHER STATEMENT HAS BEEN ISSUED TO COVER THIS SITUATION. 3 AM TEMPERATURES WERE IN THE MID 50S NORTH TO MID 60S SOUTH ACROSS THE CWA. A WEAK VORT MAX IN WI WAS CAUSING A FEW SHOWERS THERE WHILE A STRONGER SHORT WAVE WAS SEEN ON WATER VAPOR LOOPS IN MANITOBA AND DROPPING SOUTHWARD. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 345 AM CDT MON JUN 29 2015 FORECAST FOCUS ON RAIN CHANCES. TODAY...AREAS OF FOG SHOULD DISSIPATE BY 8 AM OR SO AND THEN ATTENTION TURNS TO CHANCES FOR SHOWERS AND THUNDERSTORMS. WILL MENTION SLIGHT CHANCES FOR SHOWERS THIS MORNING AND THEN INCREASE POPS THIS AFTERNOON FOR THUNDERSTORMS. FORECAST SOUNDINGS INDICATE WE REACH CONVECTIVE TEMPERATURES BY AROUND NOON WITH STEEPENING LAPSE RATES...AND NO CAP IN PLACE. THE HRRR INDICATES SCATTERED SHOWERS AND THUNDERSTORMS ACROSS ALL OF THE CWA THIS AFTERNOON WHILE OTHER MODELS ARE FAIRLY SIMILAR. THE SEVERE HAILERS SHOULD REMAIN NORTH ACROSS MN AND WESTERN WI AIDED BY THE DECENT MANITOBA WAVE AND COLDER AIR ALOFT. HOWEVER...SOME OF THESE STORMS MAY DRIFT INTO NORTHEAST IA LATER THIS AFTERNOON AND EARLY EVENING WITH THE POTENTIAL FOR SMALL HAIL AND GUSTY WINDS. SHEAR IS WEAK AND SBCAPES ARE PROGGED AT 1000-2000 J/KG. HOWEVER...IF TEMPERATURES CAN WARM MORE THAN EXPECTED THAN AN ISOLATED LARGE HAIL IS NOT OUT OF THE QUESTION WITH FREEZING LEVELS AT 11K FT. SPC HAS A MARGINAL RISK FOR THE POTENTIAL FOR STRONGER STORMS IN OUR NW CWA. THERE SHOULD BE PLENTY OF CLOUD COVER AGAIN WITH SOME PEEKS OF SUNSHINE. THIS WILL KEEP AFTERNOON TEMPERATURES IN THE 70S AT MOST LOCATIONS. TONIGHT...AT LEAST SCATTERED SHOWERS AND STORMS THIS EVENING WILL GRADUALLY DIMINISH WITH LOSS OF HEATING LATER THIS EVENING. THEN WILL CARRY SMALL POPS AFTER MIDNIGHT AS THE NAM/GFS INDICATE SOME LINGERING QPF WITH ANY WEAK VORT MAX IN THE DEEP NORTHWEST FLOW. HOWEVER...THE ECMWF IS COMPLETELY DRY THIS EVENING AND OVERNIGHT. MINIMUM TEMPERATURES WILL RANGE FROM THE LOWER TO MID 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 345 AM CDT MON JUN 29 2015 NOT MUCH CHANGE IN THE OVERALL PATTERN WITH NORTHWEST FLOW ALOFT TO PREVAIL THROUGH MUCH OF THE PERIOD KEEPING TEMPS NEAR TO BELOW NORMAL WHILE ALSO LIMITING ANY ORGANIZED SEVERE POTENTIAL. WILL SEE PERIODIC RAIN CHANCES AS SEVERAL UPPER LEVEL DISTURBANCES TRANSVERSE THE REGION. ONE SUCH DISTURBANCE OFF THE PACIFIC NW COAST EARLY THIS AM FAIRLY VIGOROUS LOOKING PER SATELLITE REPRESENTATION. THIS ENERGY WILL CREST THE WESTERN HEAT DOME NEXT 24 HOURS THEN HEAD SE AND INTERACT WITH IMPRESSIVE LOW LEVEL MOISTURE CONVERGENCE AND BAROCLINIC ZONE (SQUEEZED BETWEEN DRIER EASTERLY FLOW OFF LAKE MI AND ADVECTION OF DRIER AIR WITH SOUTHWEST FLOW OFF EASTERN ROCKIES INTO KS) FOR WIDESPREAD SHOWERS AND STORMS WITH POTENTIAL FOR HEAVY RAIN TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THE MAIN CHALLENGE IS JUST WHERE DOES THIS BATTLE ZONE AND HIGHER PROBABILITIES OF PRECIP AND HEAVY RAIN SET UP. LAST SEVERAL RUNS OF GFS TRENDING FROM SOUTH OF I-70 TO NEAR THE IA/MO BORDER CLOSER TO LAST FEW RUNS OF NAM. MEANWHILE...THE ECMWF IS A BIT STRONGER WITH THE GREAT LAKES HIGH AND CONSEQUENTLY WITH THE DRIER EASTERLY FLOW... AND IS ALSO SLOWER WITH MAIN SURGE OF MOISTURE FOCUSING MORE LATER WEDNESDAY AND WEDNESDAY NIGHT NEAR THE FAR SOUTHERN CWA AND ESPECIALLY JUST SOUTH/WEST OF CWA. GIVEN THE STRENGTH OF FORCING WOULD ANTICIPATE THE THREAT FOR RAINFALL AMOUNTS OF 1-2+ INCHES WHERE THIS SETS UP AND WILL NEED TO BE WATCHED VERY CAREFULLY FOR SOUTHERN CWA WHERE GROUND IS SATURATED AND RIVER LEVELS HIGH FROM SEVERAL ROUNDS OF HEAVY RAINFALL WITHIN THE PAST WEEK OR SO. GIVEN THE MODEL CONSISTENCY AND TIMING ISSUES I HAVE KEPT POPS IN THE CHANCE CATEGORY FOR NOW TUESDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGHEST FAR SOUTH. IN THE WAKE OF THIS SYSTEM WOULD ANTICIPATE 24+ HRS OF DRY AND PLEASANT WEATHER THURSDAY POSSIBLY INTO FRIDAY WITH SURFACE RIDGING AND EASTERLY FLOW. THEN...OPERATIONAL GFS AND MANY OF GFS ENSEMBLE MEMBERS ALONG WITH HI-RES ECMWF SUGGEST ANOTHER DISTURBANCE ACCOMPANIED BY RAIN CHANCES ESPECIALLY THE SOUTHERN CWA DEVELOPING FRIDAY AND LINGERING INTO FRIDAY NIGHT. IF THIS TIMING HOLDS THEN HAVE AN OPPORTUNITY TO SNEAK IN A DRY AND SEASONABLE 4TH OF JULY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1235 PM CDT MON JUN 29 2015 LOCALIZED MVFR CONDITIONS AT KBRL WILL GIVE WAY TO VFR CONDITIONS BY 20Z/29. OTHERWISE EXPECT VFR CONDITIONS THROUGH 06Z/30 WITH ISOLATED TO SCATTERED SHRA/TSRA DEVELOPING DURING PEAK HEATING. IF A SHRA/TSRA AFFECTS A TAF SITE THEN A BRIEF PERIOD OF MVFR/IFR CONDITIONS IS POSSIBLE. AFT 06Z/30 VFR CONDITIONS ARE EXPECTED TO CONTINUE. HOWEVER...WET GROUND AND LIGHT WINDS MAY ALLOW PATCHY MVFR/IFR CONDITIONS IN FOG TO DEVELOP PRIOR TO SUNRISE TUESDAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...08 SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...05 AVIATION...08
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1219 PM MDT MON JUN 29 2015 .UPDATE... ISSUED AT 859 AM MDT MON JUN 29 2015 UPDATED FORECAST TO BETTER REFLECT THE LIGHT RAIN SHOWERS MOVING SOUTH-SOUTHEAST MAINLY THROUGH FAR EAST CENTRAL COLORADO AND FAR WESTERN KANSAS THIS MORNING. && .SHORT TERM...(TODAY THROUGH WEDNESDAY NIGHT) ISSUED AT 241 AM MDT MON JUN 29 2015 NORTHERLY FLOW WILL CONTINUE ACROSS THE PLAINS EAST OF THE ROCKIES AS A RIDGE PERSISTS OVER CENTRAL UTAH. BY WEDNESDAY THE RIDGE RETROGRESSES TO NEVADA. SURFACE HIGH PRESSURE WILL CONTINUE OVER THE AREA TODAY AND TONIGHT. THE HIGH WILL BE REPLACED BY WEAK LOW PRESSURE TUESDAY AND TUESDAY NIGHT. A SURFACE TROUGH WILL SHIFT EAST ACROSS NORTHWEST KANSAS WEDNESDAY FOLLOWED BY HIGH PRESSURE WEDNESDAY NIGHT. PLAN ON CHANCE AND SLIGHT CHANCE POPS ACROSS THE WESTERN PORTION OF THE FA TODAY AND INTO EARLY THIS EVENING. THE NAM AND THE HRRR HAVE A GOOD HANDLE ON STORMS DEVELOPING EARLY THIS MORNING. THE MODELS ARE ALSO INDICATING STORMS THIS AFTERNOON. DYNAMICS SHOULD SLOWLY MOVE TO THE SOUTHWEST FA EARLY THIS EVENING WITH POPS DECREASING TO NIL VALUES. POPS WILL REMAIN NIL OVERNIGHT AND TUESDAY. A SHORTWAVE MOVES THROUGH THE FLOW LATE TUESDAY EVENING. SLIGHT CHANCE LOOKS ON TRACK FOR THAT TIME PERIOD SINCE MOISTURE REMAINS LIMITED. STORMS WEDNESDAY AFTERNOON AND EVENING SHOULD BE CONFINED TO THE FRONTAL BOUNDARY OVER EASTERN COLORADO. ONCE AGAIN MOISTURE IS LIMITED SO SLIGHT CHANCE POPS SHOULD BE APPROPRIATE. MAX TEMPERATURES TODAY AND WEDNESDAY SHOULD RISE INTO THE LOWER 90S IN THE WESTERN FA AND THE UPPER 90S (SIMILAR TO YESTERDAY) IN THE EAST. 850 TEMPERATURES WILL SUPPORT SURFACE TEMPERATURES NEAR 100 DEGREES TUESDAY. APPARENT TEMPERATURES ARE NOT AT HEAT ADVISORY LEVELS BUT THIS WILL NEED TO BE MONITORED. MIN TEMPERATURES SHOULD RANGE FROM 65 TO 70 WITH COOLEST READINGS IN EASTERN COLORADO. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 241 AM MDT MON JUN 29 2015 THE BEST CHANCES FOR PRECIP ARE AT THE START OF THE PERIOD ON THURSDAY AND FRIDAY AS AN UPPER LEVEL TROUGH PASSES ACROSS THE NORTHERN PLAINS AND A FRONTAL BOUNDARY STALLS OUT OVER THE AREA. MEANWHILE...THE UPPER LEVEL RIDGE OVER THE WESTERN HALF OF THE CONUS WILL CONTINUE TO BREAK DOWN. DRIER AIR IS EXPECTED TO MOVE INTO THE NORTHERN PORTION OF THE FORECAST AREA ON FRIDAY AND PROGRESS SOUTH. DRY CONDITIONS LOOK TO PERSIST FOR MUCH OF THE HIGH PLAINS FOR THE WEEKEND AS THE UPPER LEVEL RIDGE SOMEWHAT REBOUNDS ALTHOUGH SOME WEAK DISTURBANCES COULD GENERATE PRECIP CHANCES FOR PARTS OF THE AREA. HIGHS ON THURSDAY ARE EXPECTED TO BE IN THE 80S...COOLING A COUPLE DEGREES ON FRIDAY BEFORE REBOUNDING INTO THE MID 80S TO MID 90S FOR THE WEEKEND AS THE RIDGE REBUILDS. LOWS ARE FORECAST IN THE UPPER 50S TO MID 60S THURSDAY NIGHT AND FRIDAY NIGHT. TEMPERATURES FOR SATURDAY NIGHT LOOK TO BE SLIGHTLY WARMER AND IN THE 60S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1142 AM MDT MON JUN 29 2015 VFR CONDITIONS AND LIGHT WINDS EXPECTED AT MCK AND GLD THROUGH THE TAF PERIOD. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...LOCKHART SHORT TERM...FS LONG TERM...JBH AVIATION...LOCKHART
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
220 PM EDT MON JUN 29 2015 .UPDATE... ISSUED AT 220 PM EDT MON JUN 29 2015 SCATTERED CONVECTION IS STARTING TO POP UP ON SCHEDULE ACROSS THE WESTERN HALF OF KENTUCKY AS TEMPERATURES HAVE CLIMBED INTO THE LOW 80S...WITH DEW POINTS IN THE MID 60S. MAINLY FRESEHENED UP THE HOURLY TEMPERATURES AND DEW POINTS TO JIVE BETTER WITH THE LATEST TRENDS IN OBSERVATIONS. UPDATE ISSUED AT 1112 AM EDT MON JUN 29 2015 THE FORECAST REMAINS ON TRACK TODAY. THE FIRST SHORT WAVE TROUGH...WITH THE MAJORITY OF ITS ASSOCIATED FORCING NORTH OF THE OHIO RIVER...IS ON ITS WAY OUT. WE NOW AWAIT THE NEXT WAVE TO COME IN FROM THE NORTHWEST...WHICH COMBINED WITH HEATING AND SOME SURFACE CONVERGENCE WILL ALLOW FOR ANOTHER ROUND OF SCATTERED CONVECTION. AN ISOLATED SEVERE STORM IS STILL A POSSIBILITY... DEPENDING ON HOW MUCH INSTABILITY CAN BUILD IN THIS AFTERNOON. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 745 AM EDT MON JUN 29 2015 FORECAST WAS NOT IN TOO BAD OF SHAPE. BROUGHT THE GRIDS IN LINE WITH LATEST RADAR TRENDS AND HOURLY OBS. SOUTHERN END OF BAND OF SHOWERS IS STRUGGLING TO HOLD TOGETHER...BUT THERE HAS BEEN SOME REDEVELOPMENT OVER THE PAST HOUR. BASED ON RADAR MOSAIC...HIGHEST POPS IN THE NORTH AND ESPECIALLY I-64 CORRIDOR LOOKS RIGHT ON TARGET FOR THE START OF THE MORNING. WITH ADDITIONAL SHORTWAVE ENERGY DROPPING INTO THE BASE OF OUR OVERHEAD TROUGH...STILL EXPECTING REDEVELOPMENT OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON...LINGERING INTO THE EARLY EVENING. && .SHORT TERM...(TODAY THROUGH TUESDAY) ISSUED AT 417 AM EDT MON JUN 29 2015 HIGH AMPLITUDE PATTERN ALOFT WILL MEAN EASTERN CONUS TROUGH WILL DOMINATE OUR WEATHER THROUGH THE SHORT TERM. BAND OF SHOWERS AND THUNDERSTORMS ASSOCIATED WITH A SFC FRONTAL SYSTEM CONTINUES TO MOVE EASTWARD ACROSS THE COMMONWEALTH THIS MORNING. MODELS...AND ESPECIALLY THE HRRR SUGGEST THAT THIS ACTIVITY WILL GRADUALLY WEAKEN AS IT MOVES INTO OUR AREA AROUND DAWN...DUE TO UPPER LEVEL SUPPORT SHEARING OUT. HOWEVER...ADDITIONAL SHORTWAVE ENERGY ALOFT ROUNDING THE BASE OF AN EASTERN CONUS TROUGH SHOULD HELP REGENERATE ACTIVITY THROUGH THE AFTERNOON. SHEAR AND INSTABILITY APPEAR SUFFICIENT FOR THE THREAT OF SOME STRONG TO SEVERE THUNDERSTORMS...MAINLY THROUGH THE AFTERNOON AND EARLY EVENING. BUT THERE ARE SOME LIMITING FACTORS FOR EXAMPLE... CLOUD COVER...LESS THAN IMPRESSIVE MID LEVEL LAPSE RATES...AND FORCING...THE STRONGEST OF WHICH MAY REMAIN FURTHER NORTH AND WEST OF OUR AREA. THEREFORE SEVERE THREAT MAY BE MORE ISOLD IN NATURE WITH RESPECT TO COVERAGE. JUST THE SAME WITH SPC PLACING OUR AREA IN A SLIGHT RISK TODAY WILL CONTINUE TO ADVERTISE THE POTENTIAL. WITH THE APPROACH OF THE SFC TROUGH TO OUR WEST AND MID LEVEL CLOUD COVER CURRENTLY MOVING INTO OUR AREA EXPECT TEMPERATURES TO BEGIN TO REBOUND ACROSS MUCH OF THE AREA BETWEEN NOW AND SUNRISE. .LONG TERM...(TUESDAY NIGHT THROUGH SUNDAY) ISSUED AT 351 AM EDT MON JUN 29 2015 UPPER LEVEL MODELS CONTINUE TO SUPPORT A LONGWAVE TROUGH ACROSS MUCH OF THE EASTERN CONUS TO START OFF THE PERIOD...KEEPING THE OHIO RIVER VALLEY IN NW FLOW REGIME FROM TUESDAY NIGHT THROUGH FRIDAY. THE AXIS OF THE TROUGH WILL THEN SHIFT DIRECTLY OVER KY AS ANOTHER SHORTWAVE DIGS SOUTHWARD FROM CANADA TO START OFF THE WEEKEND. FINALLY...THE UPPER LEVEL LONGWAVE PATTERN WILL SLOWLY DAMPEN AS WE HEAD INTO THE END OF THE EXTENDED PERIOD SUNDAY INTO MONDAY. HOWEVER...BY THE WEEKEND MODELS SHOW QUITE A BIT OF DISCONTINUITY...SO THE EXACT TIMING AND MAGNITUDE OF THE UPPER LEVEL TROUGH WILL BE SOMEWHAT LOW CONFIDENCE. WITH THE GENERAL NW FLOW...EXPECT SHORTWAVES TO CONTINUE TO TRAVEL SE AND INTO THE OHIO RIVER VALLEY. THIS WILL RESULT IN SEVERAL SURFACE LOW PRESSURE CENTERS AND FRONTAL BOUNDARIES PASSING THROUGH THE REGION...CREATING THE ENERGY AND LIFT TO PRODUCE SHOWERS AND THUNDERSTORMS. AS HAS BEEN THE CASE OVER THE LAST FEW WEEKS...EXPECT MOST WIDESPREAD ACTIVITY TO BE RIGHT ALONG AND JUST AHEAD OF THE FRONTAL BOUNDARY...PEAKING IN SEVERITY DURING THE AFTERNOON AND EARLY EVENING HOURS IN CONJUNCTION WITH THE PEAK HEATING. THE FIRST OF THESE BOUNDARIES WILL BE EXITING TUESDAY NIGHT AS THE NEXT BOUNDARY TO OUR NORTH MAKES A SHIFT SOUTHWARD. THIS SECOND BOUNDARY IS EXPECTED TO MAKE IT INTO THE REGION WEDNESDAY NIGHT...AND ACCORDING TO THE LATEST 00Z RUN OF THE GFS40...SHOULD BECOME STALLED OUT ACROSS THE REGION THROUGH THE DAY FRIDAY AS THE UPPER LEVEL TROUGH BACK-BUILDS ACROSS THE OHIO RIVER VALLEY. ALONG THIS BOUNDARY...EXPECT SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS...WITH ANY UPPER LEVEL WAVES OF ENERGY ENHANCING CHANCES FOR A MCS TO PASS THROUGH THE REGION. THE FRONTAL BOUNDARY WILL FINALLY SHIFT SE OF THE STATE BY FRIDAY EVENING...ASSUMING MODEL TIMING PANS OUT. UNFORTUNATELY...ANOTHER WEAK FRONTAL BOUNDARY WILL HAVE FORMED TO OUR NORTH...AND WE WILL STILL BE IN VERY CLOSE PROXIMITY TO THE EXITING FRONT. UNDER SW FLOW BY THIS POINT...AND STILL IN AN UPPER LEVEL LOW PRESSURE TROUGHING PATTERN...EXPECT LESS ORGANIZED SCATTERED CONVECTION TO CONTINUE INTO THE WEEKEND...WITH BEST CHANCES STILL EXPECTED OVER THE SE CWA CLOSER TO THE EXITING FRONT. BY SUNDAY...MODEL CONFIDENCE IN CONVECTION STARTS TO DECLINE AS THERE IS LITTLE AGREEMENT IN THE PATTERN ALOFT. IF THE GFS IS CORRECT...THE UPPER LEVEL TROUGH WILL BEGIN DAMPENING/WEAKENING... BUT CONTINUED WARM SW FLOW AND A PASSING SHORTWAVE COULD BE THE SPARK FOR YET MORE SHOWERS AND THUNDERSTORMS DURING THE AFTERNOON/EVENING HOURS. BOTH THE ECMWF AND THE GFS DO SUPPORT A LARGE UPPER LEVEL CLOSED LOW PUSHING SOUTH FROM NW CANADA TO CENTRAL CANADA BY LATE IN THE WEEKEND. THIS ENERGY WILL TRANSLATE TO THE SURFACE WITH A STRONG LOW PRESSURE SYSTEM DEVELOPING ACROSS SOUTHCENTRAL CANADA...PULLING A STRONG FRONTAL BOUNDARY WHICH WILL SWEEP ACROSS MUCH OF THE CENTRAL AND EVENTUALLY EASTERN CONUS. EXACT TIMING IS STILL OBVIOUSLY IN LOW CONFIDENCE...BUT IF THIS PANS OUT ANOTHER GOOD CHANCE OF WIDESPREAD SHOWERS AND THUNDERSTORMS WILL IMPACT THE REGION AHEAD OF THE FRONTAL ZONE AS WE END THE EXTENDED PERIOD MONDAY. WITH A NW FLOW REGIME...COOLER AIR WILL BE PULLED IN FROM CANADA TO START OUT THE EXTENDED PERIOD. THEN AS THE TROUGH BACK-BUILDS AND GENERALLY SW FLOW TAKES HOLD DURING A PORTION OF THE PERIOD...WE WILL ACTUALLY CONTINUE TO PULL COOLER AIR IN FROM THE NORTH...AS WINDS BECOME MORE NW JUST TO OUR WEST. THIS...IN CONJUNCTION WITH CLOUD COVER AND POTENTIAL RAIN...WILL KEEP TEMPERATURES MODERATED THROUGH MUCH OF THE EXTENDED...AT LEAST INTO THE WEEKEND. EXPECT HIGHS IN THE UPPER 70S TO LOW 80S. BY MONDAY...ENERGY WILL BE REDIRECTED TOWARDS THE INCOMING UPPER LEVEL HIGH...CAUSING A BREAK IN THE UPPER LEVEL WIND FLOW ACROSS THE REGION. THIS WILL ALLOW FOR A BETTER PULL OF TRUE SW WIND FLOW IN THE MID AND LOW LEVELS...WHICH COMBINED WITH ANY SUNSHINE...WILL BOOST TEMPS BACK UP INTO THE MID AND MAYBE EVEN UPPER 80S FOR THE DAY. WITH PARTLY TO MOSTLY CLOUDY SKIES EXPECTED TO STICK AROUND DURING THE NIGHT...EXPECT TEMPERATURES TO REMAIN MODERATED AS WELL...STAYING AROUND THE MID AND UPPER 60S FOR EARLY MORNING LOWS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 220 PM EDT MON JUN 29 2015 SCATTERED CONVECTION WILL MOVE IN THIS AFTERNOON AND LAST THROUGH AROUND 03Z THIS EVENING...BEFORE GENERALLLY DISSIPATING. ANY DIRECT HIT FROM A SHOWER OR THUNDERSTORM WILL BRING TEMPORARY IFR CONDITIONS...HOWEVER WILL ONLY CONTINUE TO MENTION VCTS FOR NOW...GIVEN THE DISORGANIZATION OF THE CONVECTION. SUSTAINED SOUTHWEST WINDS OF AROUND 10 KTS...WITH GUSTS TO AROUND 20 KTS WILL ALSO PERSIST THROUGH EARLY EVENING...BEFORE DIMINISHING. PATCHY FOG WILL SET IN LATER TONIGHT...HOWEVER CLEARING OUT MAY BE PROBLEMATIC...SO AM ONLY CARRYING MVFR FOR NOW. ANY FOG WILL BURN OFF BY AROUND 12Z...WITH THE NEXT BATCH OF CONVECTION LIKELY HOLDING OFF UNTIL AFTER 18Z TUESDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...GEOGERIAN SHORT TERM...RAY LONG TERM...JMW AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1208 PM EDT MON JUN 29 2015 .SYNOPSIS... WARMER AND DRIER TODAY BEFORE ANOTHER ROUND OF RAIN MOVES IN THIS EVENING AND OVERNIGHT. && .NEAR TERM /THROUGH TONIGHT/... INGESTING THE RAW HRRR TEMPERATURES SHOWED TOO MUCH OF A GRADIENT BETWEEN THE MOSTLY SUNNY CONDITIONS OVER THE SOUTHERN 1/3 OF THE FORECAST AREA AND THE COOLER NORTH WHERE THE CLOUDS AND RAIN ARE EXPECTED TO TRACK THROUGH MID-AFTERNOON. THE HRRRS HOURLY TEMPERATURE EVOLUTION WAS...HOWEVER...QUITE PLAUSIBLE SO A BLEND OF PREVIOUS FORECAST WAS MADE WITH THE TEMPERED HRRR NUMBERS FOR HIGHS TODAY. MAY NEED TO RE-ADJUST SOME HIGHS ACROSS NORTHERN WV LATER AS THE LATEST UPDATE MAY HAVE NOT GONE HIGH ENOUGH. HOLDING BACK POPS A LITTLE LONGER ACROSS SOUTHWEST PENNSYLVANIA AS THE DIGGING LOW WILL TAKE SOME TIME TO ADVANCE EASTWARD. STILL UNIMPRESSED WITH CAPE NUMBERS PROGGED OFF THE NAM AND RAP ANALYSIS...SO WILL CONTINUE TO LIMIT THUNDERSTORM POTENTIAL TO JUST ISOLATED. HAVE CONTINUED LIKELY POPS DURING THE OVERNIGHT HOURS...WITH HIGHEST POPS NORTHWEST OF PITTSBURGH FOLLOWING THE TRACK OF THE LOW CENTER OVER LAKE ERIE. NOT MUCH INSTABILITY FOR THUNDERSTORMS TO WORK WITH...ESPECIALLY CONSIDERING THE WARM FRONT WILL CROSS THE REGION OVERNIGHT. THIS SHOULD CONTINUE TO LIMIT SEVERE WEATHER POTENTIAL. SOUTHERLY WINDS WILL RAISE DAYTIME HIGHS SOME 10 DEGREES FROM SUNDAYS HIGH TEMPERATURES...ALTHOUGH THIS WILL REMAIN BELOW NORMAL. OVERNIGHT TEMPERATURES WILL BE CLOSE TO NORMAL AS WARM ADVECTION WILL CONTINUE. TAX/TG && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... BROAD UPPER TROUGH WILL REMAIN ACROSS THE EASTERN UNITED STATES TUESDAY AND WEDNESDAY. SCATTERED THUNDERSTORMS WILL CONTINUE THROUGH THE PERIOD...ESPECIALLY ACROSS SOUTHERN COUNTIES TUESDAY AFTERNOON. THERE WILL BE LITTLE CHANGE IN THE OVERALL TEMPERATURE PATTERN...KEEPING DAYTIME HIGHS SLIGHTLY BELOW NORMAL AND OVERNIGHT LOWS AROUND NORMAL. && .LONG TERM /THURSDAY THROUGH SUNDAY/... UNSETTLED WEATHER WILL CONTINUE THROUGH THE EXTENDED AS THERE IS MINIMAL CHANGE EXPECTED TO THE LONGWAVE PATTERN AND TROUGHING REMAINS THE DOMINANT FEATURE. LATEST MODEL CONSENSUS IS IN FAIRLY GOOD AGREEMENT WITH THIS...HOWEVER AGREEMENT AND CONTINUITY IN ANY FINER DETAILS IS LACKING SO THE FORECAST CONTINUES TO BE FAIRLY BROAD BRUSHED. AT THIS TIME THE HIGHEST PROBABILITY OF SEEING SHOWERS AND STORMS LOOKS TO BE THURSDAY WHEN UPPER LEVEL DYNAMICS ARE FAVORABLE AND SATURDAY WHEN A SHORTWAVE IS PROGGED TO CROSS THE REGION. TEMPERATURES WILL REMAIN SLIGHTLY BELOW NORMAL...WITH A WARMING TREND TOWARDS THE END OF THE PERIOD AS THE LONGWAVE PATTERN BECOMES MORE ZONAL. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... VFR MID LEVEL CLOUDS ARE EXPECTED TO INCREASE THIS MORNING AS A WARM FRONT APPROACHES...WITH A CHANCE OF SHOWERS LATE THIS MORNING POSSIBLE OUT AHEAD OF THE FRONT. THESE SHOULD BE LIGHT AND DO NOT ANTICIPATE MCU IMPACT TO CIGS/VIS. LATER TODAY MORE SUBSTANTIAL PRECIPITATION WILL DEVELOP AS THE WARM FRONT APPROACHES BUT LATEST MODEL SOUNDINGS STILL INDICATE CLOUD LEVELS WILL NOT DROP TO AOB 3KFT. THUNDERSTORMS WILL BE POSSIBLE LATE THIS AFTERNOON BUT THIS ALL DEPENDS ON HOW MUCH INSTABILITY IS REALIZED IN LOWER LEVELS. AT THIS POINT THE THREAT OF ANY SEVERE WEATHER LOOKS TO REMAIN SOUTHWEST OF THE AREA...AND ANY ACTIVITY LATER TONIGHT ALONG THE FRONT SHOULD BE LIMITED. .OUTLOOK.../TUESDAY THROUGH FRIDAY/... PERIODIC RESTRICTIONS ARE POSSIBLE THROUGH THE WEEK WITH A SERIES OF CROSSING DISTURBANCES. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
405 PM EDT MON JUN 29 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 349 PM EDT MON JUN 29 2015 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER THE UPR GREAT LKS BTWN TROF OVER ERN NAMERICA AND HI AMPLITUDE UPR RDG OVER THE ROCKIES. SHRTWV EMBEDDED IN THE NW FLOW AND ON CYC SIDE OF RIBBON OF FASTER MID LVL WINDS OVER THE NRN PLAINS INTO MN IS MOVING INTO NRN MN. COMBINATION OF DAYTIME HEATING AND DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF DEEPER MSTR/PWAT NEAR 1.30 INCHES AHEAD OF THIS FEATURE HAS TRIGGERED SCT-NMRS SHOWERS/TS OVER MAINLY THE W HALF OF THE CWA WHERE MUCAPE IS HIER NEAR 1500 J/KG. WITH SFC-6KM SHEAR NO GREATER THAN 15 TO 20 KTS OVER THE WRN CWA...STORMS HAVE BEEN PULSY/DISORGANIZED IN OUR CWA TO THE E OF A MORE IMPRESSIVE BOW ECHO THAT HAS PLOWED THRU NE MN/WRN WI. SO THERE HAVE NO SVR WX REPORTS IN THE MQT CWA. THERE APPEARS TO BE A 2ND WEAKER SHRTWV DIGGING SEWD THRU MANITOBA AND INTO FAR NW ONTARIO THAT IS MAINTAINING SOME COLDER CLD TOPS IN THAT AREA. A SFC COLD FNT ASSOCIATED WITH THIS FEATURE IS SINKING SEWD TOWARD NW LK SUP. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/TS CHANCES ASSOCIATED WITH PAIR OF SHRTWVS NOTED ABOVE. TNGT...STRONGER SHRTWV NOW PASSING THRU MN IS PROGGED TO CONTINUE TO THE SSE TO NEAR CHICAGO BY 12Z TUE WHILE SECOND DISTURBANCE MOVES TO NEAR THE KEWEENAW. ALTHOUGH THE FIRST DISTURBANCE IS STRONGER...THE SLOWER SECOND SHRTWV IS FCST TO MAINTAIN DEEP LYR QVECTOR CNVGC/AREA OF DEEPER MSTR OVER MUCH OF THE CWA THRU THE NGT. SO EVEN THOUGH NOCTURNAL COOLING WL ACT TO LIMIT CONVECTION...THIS FORCING AND DEEPER MSTR AHEAD OF APRCHG COLD FNT WL MAINTAIN HIER POPS. ALTHOUGH SOME OF THE STORMS IN THE EVNG ACROSS MAINLY THE W HALF OF THE CWA CLOSER TO THE HIER H85 THETA E/MUCAPE VALUES MIGHT BE MARGINALLY SVR...LACK OF SGNFT MSTR INFLOW INTO THE CWA/WEAK DCAPE AND DIMINISHING INSTABILITY OVERNGT WL LIMIT THE THREAT FURTHER. MID LVL DRYING/DEEP LYR QVECTOR DVGC IS FCST TO IMPACT THE FAR W LATE...SO WL FCST DIMINISHING POPS THERE OVERNGT. BUT MOIST LLVL NNW FLOW BEHIND ASSOCIATED COLD FROPA WL MAINTAIN QUITE A BIT OF LO CLD AND ADVECT SOME FOG INLAND OFF LK SUP INTO THE NW CWA OVERNGT. TUE...AS SECOND SHRTWV SLIDES SLOWLY TO THE SE...LINGERING DYNAMIC FORCING/DEEP MSTR OVER THE ERN CWA IN THE MRNG IS FCST TO EXIT IN THE AFTN AND GIVE WAY TO MID LVL SUBSIDENCE/DRYING. SO WL MAINTAIN FLAVOR OF GOING FCST THAT SHOWS DIMINISHING POPS NW-SE. WSHFT TO THE NNW/SHALLOW INFUSION OF COLD AIR BEHIND COLD FROPA WL SUPPORT EXPANSION OF LO CLDS TO THE SE. THIS LO CLD/PERHAPS SOME DRIZZLE WL BE MOST PERSISTENT OVER THE UPSLOPE HIER TERRAIN NEAR LK SUP. FARTHER INLAND...THE COMBINATION OF DAYTIME HEATING AND ADVECTION OF LLVL DRIER AIR MAY ALLOW FOR SOME SUNSHINE LATE IN THE DAY. CONSIDERING THE LLVL INFUSION OF COOL AIR WITH STEADY N WIND OFF THE CHILLY LK WATERS...LOWERED FCST MAX TEMPS. THE MERCURY SHOULD HOLD IN THE 50S AT MOST PLACES NEAR LK SUP. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 403 PM EDT MON JUN 29 2015 DECENT AGREEMENT IN OVERALL LOOK OF LARGE SCALE PATTERN THROUGH THE 4TH OF JULY WEEKEND. TROUGHING OVER EASTERN CANADA AND THE GREAT LAKES PERSISTS THROUGH THE WEEK...WITH RIDGING ALOFT BRIEFLY MOVING OVER THE GREAT LAKES FOR THE WEEKEND. HOLIDAY WEEKEND AT THIS POINT LOOKS MAINLY DRY WITH TEMPS AT OR ABOVE NORMAL. BEST CHANCE OF SHOWERS AND THUNDERSTORMS FOR THE EXTENDED OCCURS SUNDAY NIGHT AND MONDAY AS STRONGER TROUGH ALOFT AND SFC COLD FRONT WORK OVER THE UPPER GREAT LAKES REGION. TO START THE LONG TERM...TUESDAY NIGHT INTO WEDNESDAY MORNING MAIN CONCERN WILL BE LOW CLOUDS. NAM/GFS SOUNDINGS INDICATES MOISTURE LINGERS 950-900MB WELL INTO TUESDAY NIGHT AND POSSIBLY WEDNESDAY MORNING. NE WINDS OFF LK SUPERIOR BTWN DEPARTING TROUGH AND NEARING RIDGE SHOULD ALSO LEAD TO SLIGHT CHANCES OF SHOWERS INTO TUESDAY EVENING NEAR LK SUPERIOR NCNTRL WITH UPSLOPE FLOW. OVERALL HIT UP CLOUDS MORE ON TUESDAY NIGHT AND REMOVED CHANCES OF FOG. SKIES WILL CLEAR OUT ON WEDNESDAY. EVEN WITH THE SUNSHINE...THERMAL TROUGH IN LOW-LEVELS WILL KEEP TEMPS BELOW NORMAL WITH 50S NEAR LK SUPERIOR AND IN THE 60S ELSEWHERE. SFC RIDGE SETTLES ACROSS UPPER LAKES WEDNESDAY NIGHT INTO THURSDAY. GIVEN PWATS BLO 0.5 INCH AND LIGHT WINDS...EXPECT MIN TEMPS IN UPR 30S TO LOW 40S FOR THE COOLER SPOTS ON WEDNESDAY NIGHT. LAKE BREEZES SHOULD RULE ON WEDNESDAY...BUT SOUNDINGS REMAIN QUITE DRY AND WITH DEEPER MIXING...DWPNTS IN AFTN SHOULD FALL BACK INTO 30S OR 40S. NAM DWPNTS WHICH TYPICALLY HAVE HIGH BIAS SHOW MID 30S...SO THAT INDICATES HOW DRY THE AIRMASS LOOKS TO BE. MAY BE MORE CU THAN MODELS INDICATE ALONG LAKE BREEZES...BUT TOO DRY TO INCLUDE ANY POP-UP SHRA. SCATTERED SHRA/TSRA APPEAR POSSIBLE ON FRIDAY AS SHORTWAVE TROUGH SLIDES OVER ONTARIO AND SOUTHERN PORTION OF THIS WAVE MOVES INTO UPPER LAKES DURING PEAK HEATING. STRONGEST DEEP LAYER Q-VECTOR CONVERGENCE STAYS OVER NORTHERN ONTARIO...BUT FRONT SLIDING TOWARD UPR LAKES COMBINED WITH DAYTIME HEATING AND LAKE BREEZES COULD BE ENOUGH TO TRIGGER SHRA/TSRA. LOW-LEVEL MOISTURE IS MARGINAL AND FRONT IS NOT VERY STRONG...SO APPEARS LIKE ONLY LOW-CHANCES AT THIS POINT. AS ALLUDED TO EARLIER...THINKING NOW IS THAT JULY 4TH WILL BE DRY AS HIGH PRESSURE WORKS OVER THE AREA IN WAKE OF THE FRONTAL PASSAGE ON FRIDAY/FRIDAY NIGHT. BECOMING WARMER AS H85 TEMPS RISE TOWARD +14C BY END OF SATURDAY...BUT PROBABLY NOT ENOUGH LOW-LEVEL MOISTURE AND RESUTING INSTABILITY AROUND GIVEN OVERALL HIGHER HEIGHTS TO GENERATE ANY CONVECTION EVEN WITH THE PRESENCE OF LAKE BREEZES. WARMER YET ON SUNDAY AS H85 TEMPS RISE TOWARD +15C. WINDS MAINLY SOUTHERLY AHEAD OF NEXT FRONT...WHICH WILL KEEP LAKE MODIFICATION RESTRICTED TO EASTERN CWA OFF LK MICHIGAN. GIVEN ENOUGH SUNSHINE...MAX TEMPS ON SUNDAY COULD SURGE WELL INTO THE 80S FOR MUCH OF THE WEST HALF. CONSENSUS POPS OF HIGHER CHANCES SEEMED GOOD FOR SUNDAY NIGHT AS SHORTWAVE TROUGH AND COLD FRONT CROSS UPR MICHIGAN. SFC-H85 THETA-E RIDGING AHEAD OF THE FRONT AND STRONGER DYNAMICS SUPPORT THE BEST CHANCE FOR ORGANZED SHRA/TSRA THROUGH THE LONG RANGE PERIOD. LINGERING CHANCES FOR SHRA/TSRA NEXT MONDAY...WITH TIMING AND COVERAGE DETAILS TO BE WORKED OUT IN LATER FORECASTS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 150 PM EDT MON JUN 29 2015 EXPECT SOME SHRA/TS TO IMPACT MAINLY IWD AND SAW THIS AFTN WITH OCNL MVFR CONDITIONS PSBL. ALTHOUGH A TS COULD HIT CMX AS WELL...THE PROBABILITY IS TOO LO TO INCLUDE A SPECIFIC MENTION ATTM. MORE NUMEROUS SHOWERS/A LINGERINGTS WILL ARRIVE TNGT WITH THE CLOSER APRCH OF AN UPPER DISTURBANCE/COLD FNT/DEEPER MSTR. AFTER THIS FNT PASSES THE SITES...EXPECT A WSHFT TO THE NNW TO BRING IN SOME LO CLDS/FOG ALONG WITH IFR TO LIFR CONDITIONS. BY LATE MRNG...DAYTIME HEATING AND THE ARRIVAL OF SOME DRIER LLVL AIR WL LIKELY LEAD TO IMPROVEMENT AT CMX AND IWD...BUT SAW SHOULD REMAIN IFR THRU 30/18Z WITH A SLOWER ARRIVAL OF THE DRIER LLVL AIR AND A MORE FVRBL UPSLOPE WIND COMPONENT. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 349 PM EDT MON JUN 29 2015 FOR THE MOST PART...EXPECT LIGHT WINDS BELOW 20 KNOTS THROUGH THE ENTIRE FORECAST PERIOD. THE ONE EXCEPTION WILL BE THE NCENTRAL LAKE LATE TONIGHT INTO TUE AFTERNOON. N WINDS UP TO 25 KTS WILL FOLLOW THE PASSAGE OF THIS FRONT IN THAT AREA BEFORE DIMINISHING WITH THE ARRIVAL OF HI PRES LATE IN THE DAY. EXPECT PATCHY FOG TO PERSIST ACROSS THE LAKE THROUGH TUE AS A RELATIVELY MOIST AIRMASS REMAINS OVER THE REGION. THE ARRIVAL OF DRIER LLVL AIR WL DISSIPATE ANY LINGERING FOG BY WED MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...JLA AVIATION...KC MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
349 PM EDT MON JUN 29 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 349 PM EDT MON JUN 29 2015 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW NW FLOW ALF OVER THE UPR GREAT LKS BTWN TROF OVER ERN NAMERICA AND HI AMPLITUDE UPR RDG OVER THE ROCKIES. SHRTWV EMBEDDED IN THE NW FLOW AND ON CYC SIDE OF RIBBON OF FASTER MID LVL WINDS OVER THE NRN PLAINS INTO MN IS MOVING INTO NRN MN. COMBINATION OF DAYTIME HEATING AND DPVA/DEEP LYR QVECTOR CNVGC/AXIS OF DEEPER MSTR/PWAT NEAR 1.30 INCHES AHEAD OF THIS FEATURE HAS TRIGGERED SCT-NMRS SHOWERS/TS OVER MAINLY THE W HALF OF THE CWA WHERE MUCAPE IS HIER NEAR 1500 J/KG. WITH SFC-6KM SHEAR NO GREATER THAN 15 TO 20 KTS OVER THE WRN CWA...STORMS HAVE BEEN PULSY/DISORGANIZED IN OUR CWA TO THE E OF A MORE IMPRESSIVE BOW ECHO THAT HAS PLOWED THRU NE MN/WRN WI. SO THERE HAVE NO SVR WX REPORTS IN THE MQT CWA. THERE APPEARS TO BE A 2ND WEAKER SHRTWV DIGGING SEWD THRU MANITOBA AND INTO FAR NW ONTARIO THAT IS MAINTAINING SOME COLDER CLD TOPS IN THAT AREA. A SFC COLD FNT ASSOCIATED WITH THIS FEATURE IS SINKING SEWD TOWARD NW LK SUP. MAIN FCST CONCERNS IN THE SHORT TERM FOCUS ON POPS/TS CHANCES ASSOCIATED WITH PAIR OF SHRTWVS NOTED ABOVE. TNGT...STRONGER SHRTWV NOW PASSING THRU MN IS PROGGED TO CONTINUE TO THE SSE TO NEAR CHICAGO BY 12Z TUE WHILE SECOND DISTURBANCE MOVES TO NEAR THE KEWEENAW. ALTHOUGH THE FIRST DISTURBANCE IS STRONGER...THE SLOWER SECOND SHRTWV IS FCST TO MAINTAIN DEEP LYR QVECTOR CNVGC/AREA OF DEEPER MSTR OVER MUCH OF THE CWA THRU THE NGT. SO EVEN THOUGH NOCTURNAL COOLING WL ACT TO LIMIT CONVECTION...THIS FORCING AND DEEPER MSTR AHEAD OF APRCHG COLD FNT WL MAINTAIN HIER POPS. ALTHOUGH SOME OF THE STORMS IN THE EVNG ACROSS MAINLY THE W HALF OF THE CWA CLOSER TO THE HIER H85 THETA E/MUCAPE VALUES MIGHT BE MARGINALLY SVR...LACK OF SGNFT MSTR INFLOW INTO THE CWA/WEAK DCAPE AND DIMINISHING INSTABILITY OVERNGT WL LIMIT THE THREAT FURTHER. MID LVL DRYING/DEEP LYR QVECTOR DVGC IS FCST TO IMPACT THE FAR W LATE...SO WL FCST DIMINISHING POPS THERE OVERNGT. BUT MOIST LLVL NNW FLOW BEHIND ASSOCIATED COLD FROPA WL MAINTAIN QUITE A BIT OF LO CLD AND ADVECT SOME FOG INLAND OFF LK SUP INTO THE NW CWA OVERNGT. TUE...AS SECOND SHRTWV SLIDES SLOWLY TO THE SE...LINGERING DYNAMIC FORCING/DEEP MSTR OVER THE ERN CWA IN THE MRNG IS FCST TO EXIT IN THE AFTN AND GIVE WAY TO MID LVL SUBSIDENCE/DRYING. SO WL MAINTAIN FLAVOR OF GOING FCST THAT SHOWS DIMINISHING POPS NW-SE. WSHFT TO THE NNW/SHALLOW INFUSION OF COLD AIR BEHIND COLD FROPA WL SUPPORT EXPANSION OF LO CLDS TO THE SE. THIS LO CLD/PERHAPS SOME DRIZZLE WL BE MOST PERSISTENT OVER THE UPSLOPE HIER TERRAIN NEAR LK SUP. FARTHER INLAND...THE COMBINATION OF DAYTIME HEATING AND ADVECTION OF LLVL DRIER AIR MAY ALLOW FOR SOME SUNSHINE LATE IN THE DAY. CONSIDERING THE LLVL INFUSION OF COOL AIR WITH STEADY N WIND OFF THE CHILLY LK WATERS...LOWERED FCST MAX TEMPS. THE MERCURY SHOULD HOLD IN THE 50S AT MOST PLACES NEAR LK SUP. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 337 AM EDT MON JUN 29 2015 MAIN CONCERNS THROUGH THE EXTENDED IS THE POTENTIAL FOR SHOWERS AND STORMS LATE IN THE WEEK AND CONDITIONS FOR THE FOURTH. BROAD TROUGHING WILL BE IN PLACE OVER MUCH OF THE EASTERN CONUS WITH A STRONG RIDGE OVER THE WEST THROUGH THE REST OF THE WEEK...WITH MORE ZONAL FLOW PUSHING IN OVER THE UPCOMING WEEKEND. TUESDAY...THE MAIN UPPER LEVEL TROUGH AXIS WILL SHIFT TO THE EAST OF THE AREA TUESDAY...HOWEVER...ANOTHER SHORTWAVE/VORT MAX WILL SLIDE THROUGH DURING THE DAY KEEPING SLIGHT CHANCES OF RAIN SHOWERS IN THE FORECAST...ESPECIALLY FOR THE EASTERN HALF OF THE U.P. THE FAR WESTERN U.P. STANDS THE BEST CHANCE TO HAVE SOME SUNSHINE IN THE AFTERNOON AS THE BETTER LOW LEVEL MOISTURE SLOWLY SLIDES TO THE EAST AND A DRIER SURFACE HIGH BEGINS TO SLIDE INTO THE AREA FROM ONTARIO. HIGH TEMPERATURES WILL BE KEPT GENERALLY IN THE 60S BY THE CONTINUED LOW LEVEL CLOUD COVER/LIGHT RAIN. TUESDAY NIGHT THROUGH THURSDAY...THE AFOREMENTIONED DRIER HIGH PRESSURE SYSTEM WILL CONTINUE TO BUILD ACROSS THE UPPER GREAT LAKES THROUGH THIS TIME PERIOD. THIS WILL KEEP MAINLY LIGHT WINDS AND PARTLY CLOUDY TO MOSTLY CLEAR SKIES IN THE FORECAST. THE LIGHT WINDS...CLEAR SKIES AND GENERAL TROUGHING OVER THE AREA WILL ALLOW TEMPERATURES TO FALL BELOW NORMAL TUESDAY NIGHT AND WEDNESDAY NIGHT. OVERNIGHT LOWS WILL LIKELY FALL INTO MID 40S FOR THE INLAND LOCATION. NORMAL LOWS THIS TIME OF YEAR ARE IN THE LOW 50S. ONE CAVEAT IS A SHORTWAVE SLIDING ACROSS THE AREA LATE WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT. THERE WILL BE VERY LITTLE MOISTURE TO WORK WITH SO THIS SYSTEM IS EXPECTED TO BE DRY. THURSDAY NIGHT THROUGH THE EXTENDED...MODELS HAVE THE NEXT LOW PRESSURE SYSTEM AND UPPER LEVEL WAVE SLIDING ACROSS CENTRAL CANADA THURSDAY NIGHT...REACHING HUDSON BAY AROUND 12Z FRIDAY. A WEAK COLD FRONT IS PROGGED TO EXTEND SOUTH FROM THE LOW AND WILL PUSH CLOSER TO THE WESTERN U.P. FRIDAY MORNING AND INTO THE EASTERN U.P. BY SATURDAY MORNING. ALONG AND AHEAD OF THE FRONT...A FEW SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE...ESPECIALLY DURING THE DAY FRIDAY. OVERALL COVERAGE IS EXPECTED TO BE LIMITED AS MOISTURE LOOKS TO BE SCARCE WITH THE SYSTEM. MODELS ARE GENERALLY PUSHING THE COLD FRONT EAST OF THE AREA BY THE FOURTH OF JULY ALLOWING FOR DRIER CONDITIONS. UPPER LEVEL FLOW THEN BECOMES MORE ZONAL SATURDAY INTO SUNDAY ALLOWING TEMPERATURES TO WARM TO NEAR NORMAL. THE NEXT SYSTEM WILL APPROACH THE AREA BY LATE SUNDAY INTO SUNDAY NIGHT. WILL HOLD OFF ON THE DETAILS OF THAT SYSTEM FOR NOW AS IT IS AT THE VERY END OF THE FORECAST PERIOD AND A LOT CAN CHANGE WITH THAT OVER THE NEXT SEVERAL DAYS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 150 PM EDT MON JUN 29 2015 EXPECT SOME SHRA/TS TO IMPACT MAINLY IWD AND SAW THIS AFTN WITH OCNL MVFR CONDITIONS PSBL. ALTHOUGH A TS COULD HIT CMX AS WELL...THE PROBABILITY IS TOO LO TO INCLUDE A SPECIFIC MENTION ATTM. MORE NUMEROUS SHOWERS/A LINGERINGTS WILL ARRIVE TNGT WITH THE CLOSER APRCH OF AN UPPER DISTURBANCE/COLD FNT/DEEPER MSTR. AFTER THIS FNT PASSES THE SITES...EXPECT A WSHFT TO THE NNW TO BRING IN SOME LO CLDS/FOG ALONG WITH IFR TO LIFR CONDITIONS. BY LATE MRNG...DAYTIME HEATING AND THE ARRIVAL OF SOME DRIER LLVL AIR WL LIKELY LEAD TO IMPROVEMENT AT CMX AND IWD...BUT SAW SHOULD REMAIN IFR THRU 30/18Z WITH A SLOWER ARRIVAL OF THE DRIER LLVL AIR AND A MORE FVRBL UPSLOPE WIND COMPONENT. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 349 PM EDT MON JUN 29 2015 FOR THE MOST PART...EXPECT LIGHT WINDS BELOW 20 KNOTS THROUGH THE ENTIRE FORECAST PERIOD. THE ONE EXCEPTION WILL BE THE NCENTRAL LAKE LATE TONIGHT INTO TUE AFTERNOON. N WINDS UP TO 25 KTS WILL FOLLOW THE PASSAGE OF THIS FRONT IN THAT AREA BEFORE DIMINISHING WITH THE ARRIVAL OF HI PRES LATE IN THE DAY. EXPECT PATCHY FOG TO PERSIST ACROSS THE LAKE THROUGH TUE AS A RELATIVELY MOIST AIRMASS REMAINS OVER THE REGION. THE ARRIVAL OF DRIER LLVL AIR WL DISSIPATE ANY LINGERING FOG BY WED MORNING. && .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
NWS NORTH PLATTE NE
1229 PM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 826 AM CDT MON JUN 29 2015 CLOUD SHIELD EXTENDING ACROSS THE NORTH CENTRAL IS FROM THE SMOKE DEBRIS THAT IS BEING CARRIED DOWNSTREAM FROM THE ALASKA REGION. GRIDS TODAY AND THIS EVENING UPDATED FOR SKY CONDITIONS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 332 AM CDT MON JUN 29 2015 TODAY AND TONIGHT...WINDS AT 850 MB TO 750 MB ARE SOUTH ACROSS THE CNTL HIGH PLAINS THIS MORNING AND A DISTURBANCE IS DROPPING SOUTH VERY QUICKLY IN THE NORTHWEST FLOW. STORMS ARE UNDERWAY FROM SPEARFISH SD TO CHEYENNE WY AND THE HRRR...RAP...ARW...NMM AND NAM CARRY THIS ACTIVITY INTO THE PANHANDLE AND SWRN NEB FOR A FEW HOURS THIS MORNING. SATELLITE TIMING TOOLS INDICATE THE DISTURBANCE NORTH OF THE BLACK HILLS WOULD CLEAR SWRN NEB 13Z-14Z THIS MORNING. THE ARW AND NMM MODELS SUGGEST A SMALL DISTURBANCE ON SATELLITE ACROSS SERN SASKATCHEWAN THIS MORNING COULD SPAWN ISOLATED SHOWERS AND TSTMS THIS AFTN ACROSS NCNTL NEB. THIS FEATURE IS UNDER REVIEW GIVEN THE LIMITED RADAR COVERAGE ACROSS ND AND THE LACK OF LOW LEVEL CONVERGENCE SHOWN THE MODEL CONSENSUS. THE NAM SHOWS SOUTH WINDS DEVELOPING TONIGHT BELOW 750 MB ACROSS SWRN NEB AND THIS COULD PROVIDE AN OPPORTUNITY FOR MORE CONVECTIVE DEVELOPMENT. IN FACT...SOUTH WINDS SHOULD CONTINUE TODAY ACROSS THE CNTL HIGH PLAINS ALONG HWY 385 AIMED AT THE BLACK HILLS WHICH COULD CAUSE STORMS TO FIRE ON THE BLACK HILLS THIS AFTN. THE MODEL PREDICTABILITY OF THE ONGOING CONVECTION WOULD APPEAR LOW GIVEN THAT THE RAP AND NAM SHOW NO ELEVATED INSTABILITY ACROSS THE PANHANDLE. THUS FORECAST RAIN CHANCES THIS AFTN AND TONIGHT ARE UNCERTAIN. OTHERWISE...MIXING HEIGHTS RISE TO 700 MB TODAY ALLOWING FOR A BUMP IN TEMPERATURES. HIGHS IN THE LOWER 90S SHOULD BE WIDESPREAD WITH NEARLY CLEAR SKIES. DEW POINTS IN THE 50S TO AROUND 60 SHOULD CONTINUE TODAY AND TONIGHT ALLOWING FOR ONE MORE RADIATION NIGHT WITH LOWS IN THE UPPER 50S TO LOWER 60S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 332 AM CDT MON JUN 29 2015 SYNOPTIC PATTERN REMAINS HIGHLY AMPLIFIED THROUGH THE MIDDLE OF THE WEEK WITH ANTICYCLONIC FLOW CENTERED OVER THE GREAT BASIN...AND A TROUGH TO THE EAST CENTERED OVER THE GREAT LAKES REGION. THIS LEAVES THE CWA IN PERSISTENT NORTHWEST FLOW ALOFT. A SERIES OF SHORTWAVE TROUGHS WILL ATTEMPT TO FLATTEN THE WESTERN CONUS RIDGE AS THEY TRAVERSE TROUGH SOUTHERN CANADA. THE FIRST SHORTWAVE APPROACHES THE CWA ON TUESDAY. LOW LEVEL SOUTHWESTERLY FLOW WILL PUSH H85 TEMPS ABOVE 30C IN SOUTHWEST NEBRASKA. LATEST GUIDANCE HAS TRENDED WARMER FOR HIGH TEMPS ON TUESDAY...WITH THE MAV NOW NEARING 100 FOR PARTS OF THE AREA. HOWEVER...MODELS CONTINUE TO SHOW A CIRRUS SHIELD SPREADING OVER THE CENTRAL PLAINS AS A SURGE OF MOISTURE AOA 500MB ROUNDS THE TOP OF THE WESTERN CONUS RIDGE. STILL TRENDED HIGHS UP A DEGREE OR TWO...BUT KEPT A CONSERVATIVE APPROACH GIVEN POTENTIAL CLOUD COVER. A WEAK COLD FRONT MOVES THROUGH TUESDAY EVENING AND NIGHT AS THE SHORTWAVE PASSES ALOFT. ISOLATED STORMS WILL BE POSSIBLE ALONG AND BEHIND FRONT TUESDAY NIGHT. SHEAR WILL BE STRONG ENOUGH TO SUPPORT A FEW STRONG STORMS...BUT MODEL BUFR SOUNDINGS SHOW THAT ANY ACTIVITY WILL BE HIGHLY ELEVATED DUE TO DRY LOW LEVELS SO GUSTY WINDS WOULD BE THE PRIMARY THREAT. BEST CHANCES FOR STORMS WILL LIKELY REMAIN JUST EAST OF THE CWA WHERE THE LLJ WILL BE FOCUSED AND BETTER MOISTURE RESIDES. TEMPERATURES WILL BE A FEW DEGREES COOLER WEDNESDAY BUT STILL RANGE FOR THE MID 80S TO LOW 90S. ISOLATED TO SCATTERED STORM CHANCES ENTER THE FORECAST ONCE AGAIN WEDNESDAY NIGHT AND THURSDAY AS THE NEXT UPPER LEVEL SHORTWAVE APPROACHES FROM THE NORTHWEST. MODELS REMAIN IN FAIR AGREEMENT THROUGH THE END OF THE WEEK AS A RIDGE ALOFT BUILDS OVER THE CENTRAL CONUS TO END THE WEEK WITH DRY CONDITIONS EXPECTED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1221 PM CDT MON JUN 29 2015 VISUAL FLIGHT RULES FORECAST FOR TERMINALS KLBF AND KVTN THROUGH 18Z TUESDAY. MODELS IN GOOD AGREEMENT WHERE SURFACE BOUNDARY WILL BECOME THE FOCUS FOR CONVECTION BEYOND THE PERIOD. FOR NOW SOME HIGH CLOUDS AND THE ADVECTION OF SMOKE WILL BE THE IMPACTS. LATEST VISIBLE SATELLITE HAS SMOKE ALONG AND EAST OF ONL. && .LBF WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...KECK SHORT TERM...CDC LONG TERM...MARTIN AVIATION...KECK
AREA FORECAST DISCUSSION
NWS ALBUQUERQUE NM
322 PM MDT MON JUN 29 2015 .SYNOPSIS... STORM COVERAGE WILL LOWER ON TUESDAY AND MOST OF WEDNESDAY DUE TO DRIER AIR BEING ENTRAINED INTO THE UPPER HIGH. A BACK DOOR COLD FRONT WILL FOCUS STORMS ACROSS NORTH CENTRAL AND NORTHEAST AREAS LATER WEDNESDAY AND CREATE AN UPTICK IN STORM COVERAGE THURSDAY/FRIDAY ACROSS NORTHERN AND CENTRAL NEW MEXICO. STORMS CONTAINING HEAVY RAIN WILL BE COMMONPLACE DURING THIS PERIOD. STORM COVERAGE WILL GRADUALLY LESSEN DURING THE WEEKEND AS MOISTURE GETS RECYCLED WITHIN THE UPPER HIGH. AFTERNOON TEMPERATURES WILL RISE TO ABOVE NORMAL TUESDAY/WEDNESDAY BUT GRADUALLY LOWER FROM EAST TO WEST THURSDAY AND FRIDAY THANKS TO BACK COLD FRONTAL INTRUSION. && .DISCUSSION... SHOWERS AND THUNDERSTORMS WERE A BIT SLOWER TO EVOLVE TODAY BUT ARE STARTING TO GAIN A LITTLE BIT OF STEAM AS A WEAK SHORTWAVE DROPS SOUTHWARD OUT OF COLORADO. A WEAK EAST TO WEST LOW LEVEL MOISTURE PUSH WILL ALSO ACT TO CONCENTRATE STORM ACTIVITY THE REST OF TODAY. ONGOING FLASH FLOOD WATCH LOOKS TO BE SOLID ENOUGH...ESPECIALLY FOR THE SANGRE DE CRISTOS. THE LATEST HRRR HAS MOST OF THE ACTIVITY SHIFTING SOUTHWARD FROM THE WATCH AREA BY MID TO LATE EVENING SO TIMING LOOKS DECENT ENOUGH. PERHAPS LESSENING IMPACTS BY 10 PM. DID BEEF UP POPS ACROSS THE EAST TO REFLECT CURRENT AND EXPECTING CONDITIONS AS THE CELLS MOVE SOUTHWARD. MODELS STILL SHOW DRIER AIR GETTING ENTRAINED INTO THE EASTERN EDGE OF THE UPPER HIGH ON TUESDAY. STORM COVERAGE WILL BE MUCH LESS COMPARED TO THE PAST FEW DAYS. THE FOOTPRINT OF HEAVIER RAIN CELLS WILL ALSO BE LESS. THUS THE FLASH FLOOD THREAT WILL BE MUCH LESS. THE DRIER AIR WILL BE AROUND INTO WEDNESDAY BEFORE ANOTHER SURGE OF MOISTURE VIA A BACK DOOR COLD FRONT COMES INTO PLAY LATER WEDNESDAY ACROSS NC AND NE AREAS. THE MODELS ARE REALLY PAINTING HEAVIER QPF NUMBERS ACROSS THE NORTHEAST THIRD TO HALF AND HAVE BEEN SHOWING THAT TREND FOR THE PAST SEVERAL DAYS. EXTENDED HIGHER POPS ACROSS PORTIONS OF THE PLAINS TO ACCOUNT FOR THIS TREND INTO WEDNESDAY NIGHT. AFTERNOON TEMPS WILL TREND ABOVE NORMAL DURING THIS PERIOD AND SHOULD BE ON THE HOTTER SIDE. COOLING WILL TAKE PLACE THURSDAY ALTHOUGH PWAT VALUES WILL BE ON THE HIGHER SIDE THANKS TO ANOTHER BACK DOOR COLD FRONTAL SURGE. ONCE AGAIN...THE SANGRES SHOULD GET HIT PRETTY HARD AND ALSO INCLUDE MOST OF THE CENTRAL AND EVEN WESTERN MTNS. BASED ON THE UPPER HIGH POSITION...THE FOUR CORNERS SHOULD SEE THE LEAST POTENTIAL FOR HEAVY RAIN. RESIDUAL SCATTERED TO NUMEROUS STORMS SHOULD REMAIN INTO FRIDAY DUE TO HIGHER THAN NORMAL PWAT VALUES AND CONTINUED INSTABILITY. THE STEERING MOTION FOR THE STORMS WILL BECOME LESS AND LESS DURING THIS PERIOD THUS EXASPERATING FLASH FLOOD CONDITIONS. THE MODELS STILL SHOW THE UPPER HIGH GRADUALLY MOVING EASTWARD OVER NEW MEXICO DURING THE WEEKEND. ABUNDANT MOISTURE TRAPPED WITHIN THE HIGH WILL GRADUALLY RECYCLE OUT IN THE FORM OF ISOLATED TO SCATTERED STORMS. THE FOOTPRINT OF HEAVIER RAIN WILL ALSO LESSEN DURING THIS PERIOD WHILE TEMPERATURES GRADUALLY WARM. PORTIONS OF THE MEXICAN MOISTURE PLUME COULD START TO IMPACT WESTERN AREAS EARLY NEXT WEEK BUT THAT WILL BE DEPENDENT ON THE UPPER HIGH POSITION. THE GFS IS MORE BULLISH MOVING IT EASTWARD THAN THE ECMWF. THE ECMWF IS MORE BULLISH WITH ANOTHER BACK DOOR COLD FRONTAL INFLUENCE EARLY NEXT WEEK. WILL CONTINUE TO MONITOR THOSE TRENDS. 50 && .FIRE WEATHER... STILL LOOKING FOR WET WEATHER FOR THE NEXT WEEK....WITH TUESDAY BEING THE ONLY EXCEPTION. OVERNIGHT HUMIDITY RECOVERIES WILL BE MAINLY GOOD TO EXCELLENT THROUGH THE PERIOD...WITH POCKETS OF POOR TO FAIR VENTILATION EACH DAY. FOR THE REST OF TODAY AND TONIGHT...SHOWERS AND THUNDERSTORMS HAVE ALREADY FORMED ACROSS MUCH OF THE AREA...AND STEERING FLOW IS A LITTLE BIT STRONGER THAN YESTERDAY...BUT STILL TOWARD THE SOUTH AND SOUTHWEST...WITH MORE WESTERLY FLOW ACROSS SOUTHERN AREAS. THUS...THE SAME AREAS THAT HAVE BEEN RECEIVING RAIN IN THE LAST FEW DAYS...WILL LIKELY RECEIVE MORE THROUGH TONIGHT. ADDITIONALLY...MUCH OF THE EASTERN PLAINS WILL GET A BOOST IN STORM COVERAGE THANKS TO A WEAK UPPER LEVEL DISTURBANCE AND JET STREAK NUDGING INTO THE PLAINS. AFTER STORMS MOVE SOUTHWEST AND DIMINISH TONIGHT...DRIER MID LEVEL AIR WILL BE USHERED INTO THE AREA. THE DRIER AIR WILL ALLOW FOR A BIT OF A DOWN DAY IN TERMS OF STORM COVERAGE ON TUESDAY. THE FAVORED AREA FOR STORMS WILL BE ACROSS THE NORTHERN AND WESTERN MTNS...AND PERHAPS A FEW LOCALES IN BETWEEN ON THE NW PLATEAU. MEANWHILE...TEMPS WILL BE QUITE TOASTY...WITH MOST AREAS A FEW TO 10 DEGREES ABOVE NORMAL. SHOWERS AND THUNDERSTORMS WILL FORM AGAIN OVER THE HIGH TERRAIN ON WEDNESDAY. HOWEVER...A BOUNDARY MOVING INTO THE NORTHEAST WILL PROVIDE ADDITIONAL FOCUS FOR STORMS. THAT BOUNDARY WILL REMAIN A FOCUS ON THURSDAY...BEFORE ANOTHER BACK DOOR FRONT SLIDES INTO THE PLAINS LATE THURSDAY AND EARLY FRIDAY. THIS LATTER BOUNDARY SHOULD PUSH THROUGH THE GAPS OF THE CENTRAL MOUNTAIN CHAIN BY FRIDAY MORNING...ALLOWING SOME LOW LEVEL MOISTURE TO SPILL WESTWARD...AND REPLENISH THE ATMOSPHERE. MEANWHILE...LOW LEVEL MOIST EASTERLY UPSLOPE FLOW WILL PERSIST ACROSS THE PLAINS. THUS...THE TREND WILL BE UPWARD IN ACTIVITY WEDNESDAY THROUGH FRIDAY. ANY STORM WILL BE CAPABLE OF HEAVY RAINFALL. THE UPPER LEVEL HIGH WILL MOVE LITTLE THROUGH THE PERIOD AS WELL...GENERALLY OVER THE NEVADA/UTAH AREA....THUS STORM MOTION WILL VARY LITTLE. IN OTHER WORDS...SLOW S TO SW STEERING FLOW WILL PREVAIL. GREATER STORM COVERAGE AND CLOUD COVER WILL ALLOW TEMPS TO TREND DOWNWARD...MOSTLY ON THURSDAY AND FRIDAY. BY THE WEEKEND...THE UPPER LEVEL HIGH WILL MOVE BACK TOWARD THE FOUR CORNERS. THUS...TEMPERATURES SHOULD RAMP BACK UP. STORM COVERAGE MAY TREND DOWNWARD SLIGHTLY AS WELL...ESPECIALLY ACROSS THE EAST. POCKETS OF POOR VENTILATION WILL FAVOR CENTRAL AND NW NM ON TUESDAY...WITH FAIR OR BETTER VENTILATION ELSEWHERE. ON WEDNESDAY...AREAS OF POOR VENTILATION MAY FAVOR CENTRAL AREAS...INCLUDING THE RIO GRANDE VALLEY...WITH MAINLY GOOD TO VERY GOOD VENT RATES ELSEWHERE. MORE WIDESPREAD POOR AND FAIR VENTILATION IS EXPECTED FOR THURSDAY ALONG THE RIO GRANDE VALLEY AND CENTRAL MTN CHAIN. VENTILATION MAY CONTINUE TO TREND DOWNWARD FOR FRIDAY. 34 && .AVIATION... 18Z TAF CYCLE NUMEROUS SHRA/TSRA EXPECTED THIS AFTN. STORMS WILL INITIALLY DEVELOP OVER THE HIGH TERRAIN AND PORTIONS OF EASTERN NM DUE TO A WEAK BOUNDARY THAT HAS NUDGED INTO THE AREA. LATER THIS AFTN...STORMS WILL SPREAD OVER THE LOWER ELEVATIONS OF CENTRAL AND WESTERN NM. MVFR CIGS/VSBYS AS WELL AS MTN OBSCURATIONS ARE POSSIBLE IN THE STRONGER STORMS DUE TO VERY HEAVY RAIN. SOME STORMS MAY ALSO PRODUCE HAIL AND GUSTY WINDS. STORMS WILL DIMINISH FROM NORTH TO SOUTH THIS EVENING...AND MOST STORM SHOULD DIMINISH BY 06Z. LESS CONVECTIVE ACTIVITY EXPECTED FOR TUESDAY WHEN THUNDERSTORMS WILL BE MOSTLY LIMITED TO THE HIGHEST TERRAIN. && .PRELIMINARY POINT TEMPS/POPS... FARMINGTON...................... 63 98 65 100 / 40 5 10 10 DULCE........................... 50 90 53 92 / 40 20 30 30 CUBA............................ 53 88 57 90 / 40 20 20 40 GALLUP.......................... 56 94 56 95 / 30 20 20 20 EL MORRO........................ 55 90 55 91 / 30 30 20 30 GRANTS.......................... 56 92 58 94 / 30 10 10 20 QUEMADO......................... 57 90 57 91 / 30 20 20 40 GLENWOOD........................ 59 93 60 93 / 40 20 20 50 CHAMA........................... 49 83 52 84 / 40 30 40 50 LOS ALAMOS...................... 58 89 61 90 / 40 30 30 40 PECOS........................... 55 86 58 87 / 40 30 30 50 CERRO/QUESTA.................... 49 85 52 85 / 40 30 30 40 RED RIVER....................... 46 75 49 75 / 40 30 40 60 ANGEL FIRE...................... 48 80 52 78 / 30 30 40 70 TAOS............................ 49 87 54 87 / 40 20 20 20 MORA............................ 51 84 56 83 / 40 30 30 50 ESPANOLA........................ 55 94 59 95 / 30 20 20 20 SANTA FE........................ 58 88 61 89 / 40 20 20 40 SANTA FE AIRPORT................ 58 91 61 92 / 40 5 5 20 ALBUQUERQUE FOOTHILLS........... 64 94 66 95 / 50 10 10 20 ALBUQUERQUE HEIGHTS............. 66 94 68 96 / 50 0 5 10 ALBUQUERQUE VALLEY.............. 64 96 66 98 / 50 0 0 10 ALBUQUERQUE WEST MESA........... 65 97 67 98 / 40 0 5 10 LOS LUNAS....................... 63 97 66 98 / 50 0 0 10 RIO RANCHO...................... 63 96 67 97 / 40 0 5 10 SOCORRO......................... 64 96 65 97 / 40 0 0 10 SANDIA PARK/CEDAR CREST......... 58 90 61 91 / 60 10 10 30 TIJERAS......................... 58 92 61 94 / 60 10 10 30 MORIARTY/ESTANCIA............... 53 90 56 92 / 60 10 10 20 CLINES CORNERS.................. 56 88 58 89 / 60 20 20 20 GRAN QUIVIRA.................... 57 88 59 89 / 60 10 10 20 CARRIZOZO....................... 61 90 61 91 / 60 10 10 10 RUIDOSO......................... 56 82 59 84 / 60 10 10 30 CAPULIN......................... 55 90 59 86 / 10 5 10 60 RATON........................... 54 91 56 88 / 20 5 10 60 SPRINGER........................ 54 93 58 91 / 20 5 10 70 LAS VEGAS....................... 53 86 56 86 / 50 10 10 20 CLAYTON......................... 61 95 65 93 / 10 0 10 30 ROY............................. 57 92 61 91 / 20 0 0 40 CONCHAS......................... 63 98 67 98 / 50 0 0 10 SANTA ROSA...................... 62 95 64 96 / 50 0 0 10 TUCUMCARI....................... 64 98 68 98 / 50 0 0 10 CLOVIS.......................... 63 93 64 94 / 50 0 0 5 PORTALES........................ 64 94 66 95 / 50 0 0 5 FORT SUMNER..................... 64 95 65 96 / 60 0 0 5 ROSWELL......................... 66 96 66 97 / 50 0 0 5 PICACHO......................... 60 92 60 94 / 60 0 0 5 ELK............................. 58 85 59 88 / 40 0 0 10 && .ABQ WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH UNTIL MIDNIGHT MDT TONIGHT FOR THE FOLLOWING ZONES... NMZ510>516-527>529. && $$ 50
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
253 PM EDT MON JUN 29 2015 .SYNOPSIS... A STATIONARY FRONT WILL DISSIPATE ACROSS THE AREA THIS EVENING. BERMUDA HIGH PRESSURE WILL REDEVELOP TUESDAY AND PREVAIL THIS WEEK INTO THE UPCOMING WEEKEND...BRINGING SLIGHTLY ABOVE NORMAL TEMPERATURES AND TYPICAL LATE DAY THUNDERSTORMS. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM MONDAY...A FEW SHOWERS HAVE TRIED TO DEVELOP IN THE MORE MOISTURE LADEN AREAS NEAR SOUTHPORT AND ALONG THE BLACK RIVER ON THE BORDER OF BLADEN AND PENDER COUNTIES. THE HRRR CONTINUES TO SHOW THE BEST LOW-LEVEL MOISTURE IN A LINE FROM MYRTLE BEACH TO EAST OF WHITEVILLE. THUS THE AREAS EAST OF THIS LINE MAY SEE A THUNDERSTORM. ANY CONVECTION THAT IS ABLE TO DEVELOP WILL CEASE TO EXIST AFTER SUNSET. A VERY QUITE NIGHT FOR THE AREA WITH OVERNIGHT LOWS EXPECTED TO BE IN THE UPPER 60 WELL INLAND TO THE MIDDLE 70S AT THE BEACHES. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 PM MONDAY...PRIMARY HEADLINES TUE/WED IS A RETURN TO ABOVE NORMAL MAXIMUM TEMPERATURES...WITH A HIKE-UP IN RAIN CHANCES LATE TUE AND WED AS A SHORT-WAVE ALOFT APPROACHES THE APPALACHIANS AND FORCES A LEE SIDE TROUGH TOWARD THE COAST OF NE SC AND SE NC. AN ISOLATED SHOT AT CONVECTION LATE TUESDAY AFTERNOON ALTHOUGH A MID-LEVEL DRY LAYER WILL NOT ERODE UNTIL CLOSE TO 00Z...SQUASHING RAIN CHANCES MUCH OF THE DAY TUESDAY IN THE EARLY GOING...UNTIL COLUMN WETTING ARRIVES TUESDAY NIGHT. EXPECTED TEMPERATURES AT ILM WILL RESULT IN POTENTIALLY AROUND THE 5TH WARMEST JUNE ON RECORD BY THE CLOSE OF TUESDAY. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 3 PM MONDAY...MID LEVEL TROUGH FLATTENS AND RETROGRADES THURSDAY AND FRIDAY WHICH MAY END UP BEING OUR TRANSITIONAL PERIOD FROM A RATHER NORMAL COVERAGE OF AFTERNOON CONVECTION TO A LESS ACTIVE PATTERN OVER THE WEEKEND. FLATTER FLOW SATURDAY AND SUNDAY SHOULD TRANSLATE TO LESS COVERAGE OF STORMS THOUGH A DRY AFTERNOON IS TOUGH TO FORECAST MAINLY DUE TO THE PERSISTENT PIEDMONT TROUGH AND SEA BREEZE. THEN RAIN CHANCES SHOULD RAMP BACK UP SUNDAY AND MONDAY AS ANOTHER MID LEVEL TROUGH APPROACHES FROM THE NORTHWEST. AS IS USUALLY THE CASE THIS TIME OF YEAR TEMPERATURES WILL SHOW LITTLE DAY TO DAY VARIATION BY DAY. NIGHTTIME LOWS MAY SLOW RISE THROUGH THE PERIOD DUE TO A MOISTENING BOUNDARY LAYER. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... AS OF 18Z...STILL EXPECT SOME LIGHT SHOWERS THIS AFTERNOON AS DIFFUSE FRONTAL BOUNDARY BUMP UP AGAINST THE SEA BREEZE BOUNDARY. THUNDER IS NOT OUT OF THE REALM OF POSSIBILITY...BUT REMOTELY SO. MAINLY A WEST WIND THIS AFTERNOON...STRONGEST ALONG THE COAST WITH MORE OF A WEST SOUTHWEST COMPONENT. DIMINISHING SOUTHWEST FLOW THIS EVENING WITH LITTLE OR NO FOG EXPECTED. THE NAM CONTINUES TO DEVELOP SHOWERS MONDAY AFTERNOON...BUT WITH LITTLE MOISTURE TO WORK WITH. COULD SEE AN MVFR CEILING AFTER THE SUN COMES UP. EXTENDED OUTLOOK...PREDOMINATELY VFR THROUGH TUESDAY. POSSIBLE AFTERNOON SHOWERS AND STORMS WEDNESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM MONDAY...SOUTHEAST WINDS CONTINUE ALONG THE NEAR SHORE WATERS AS THE SEA BREEZE CIRCULATION DEVELOPS THIS AFTERNOON. FARTHER OFF SHORE THE WINDS ARE LIGHT FROM THE WEST TO SOUTHWEST. OVERNIGHT SOUTHWEST WINDS WILL BECOME REESTABLISHED WITH SPEEDS OF 10 TO 15 KNOTS. SEAS OF 2 TO 3 FEET ARE EXPECTED OVERNIGHT. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 3 PM MONDAY...MODERATELY BUMPY MARINE CONDITIONS ON TAP TUE/WED AS AN INLAND SURFACE TROUGH SHARPENS AND INTERACTS WITH BERMUDA HIGH PRESSURE OFFSHORE. THIS WILL RESULT IN SW WINDS 10-20 KT THROUGH THE PERIOD WITH SEAS 2-4 FEET AND PERHAPS NEAR 5 FT OUTER PORTIONS. SEAS A COMPOSITE OF SW WAVES 1-3 FT EVERY 4-5 SECONDS AND SE WAVES 2-3 FEET EVERY 7 SECONDS. A FEW TSTMS MAY IMPACT THE WATERS TUESDAY NIGHT AND COULD PRODUCE GUSTS TO 40 KT LATE TUESDAY AND EARLY WEDNESDAY IN ISOLATED LOCATIONS. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 3 PM MONDAY...SOUTHWESTERLY FLOW EXPECTED FOR THE DURATION OF THE PERIOD AS WEST ATLANTIC HIGH PRESSURE AND INLAND PIEDMONT TROUGH SHOW LITTLE VARIATION. SEAS WILL TEND TO AVERAGE 2 TO 4 FT...HIGHEST OFFSHORE. DUE TO THE PERSISTENT FETCH THE OCCASIONAL 5 FT WAVE MAY AFFECT THE OUTERMOST SECTIONS OF NORTHERN ZONES NEAR FRYING PAN SHOALS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MJC NEAR TERM...DRH SHORT TERM...MJC LONG TERM...MBB AVIATION...DL/DRH
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
156 PM EDT MON JUN 29 2015 .SYNOPSIS... A STATIONARY FRONT WILL DISSIPATE ACROSS THE AREA THIS AFTERNOON. BERMUDA HIGH PRESSURE WILL REDEVELOP TUESDAY AND PERSIST INTO THE UPCOMING WEEKEND BRINGING ABOVE NORMAL TEMPERATURES AND TYPICAL AFTERNOON AND EVENING THUNDERSTORM CHANCES. && .NEAR TERM /THROUGH TONIGHT/... AS OF 145 PM MONDAY...A FEW SHOWERS HAVE TRIED TO DEVELOP IN THE MORE MOISTURE LADEN AREAS NEAR SOUTHPORT AND ALONG THE BLACK RIVER ON THE BORDER OF BLADEN AND PENDER COUNTIES. THE HRRR CONTINUES TO SHOW THE BEST LOW-LEVEL MOISTURE IN A LINE FROM MYRTLE BEACH TO EAST OF WHITEVILLE. THUS THE AREAS EAST OF THIS LINE MAY SEE A THUNDERSTORM. ANY CONVECTION THAT IS ABLE TO DEVELOP WILL CEASE TO EXIST AFTER SUNSET. A VERY QUITE NIGHT FOR THE AREA WITH OVERNIGHT LOWS EXPECTED TO BE IN THE UPPER 60 WELL INLAND TO THE MIDDLE 70S AT THE BEACHES. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...HOT AND DRY FOR TUESDAY...BUT A RETURN TO MORE TYPICAL SUMMERTIME WEATHER WILL DEVELOP WEDNESDAY AS THE CALENDAR FLIPS TO JULY. BROAD MID-LEVEL TROUGH REMAINS ACROSS THE CONUS THROUGH MID- WEEK...BUT WITH ITS RIDGE AXIS STAYING WEST OF THE AREA...SW FLOW WILL HELP DRIVE TEMPS TO ABOVE NORMAL EVEN WITH SOME RELATIVELY LOWERED THICKNESSES. TEMPS TUESDAY WILL WARM WELL INTO THE 90S...WITH HIGHS WEDNESDAY A FEW DEGREES COOLER...BUT STILL LIKELY ABOVE CLIMO FOR THIS TIME OF YEAR. HUMIDITY WILL ALSO BEGIN TO RAMP BACK UP...ESPECIALLY WEDNESDAY...AS RETURN FLOW PUSHES ATLANTIC MOISTURE BACK INTO THE COLUMN. WHILE TUESDAY LOOKS DRY...LATE TUESDAY NIGHT A SHORTWAVE WILL ROTATE AROUND THE BASE OF THE TROUGH AND UP THROUGH THE CENTRAL CAROLINAS. THIS MAY PROVIDE ENOUGH FORCING FOR SOME LOW-END POP ACROSS WESTERN ZONES TUESDAY NIGHT. BETTER CONVECTIVE CHANCES EXIST WEDNESDAY AS PWATS RISE BACK ABOVE 1.5 INCHES AND THE TROUGH FLATTENS - ACTUALLY DRIVING SLIGHTLY LOWER THICKNESSES ACROSS THE EASTERN CAROLINAS. DO NOT ANTICIPATE WIDESPREAD SHOWERS/TSTMS...BUT THE SEA BREEZE AND PIEDMONT TROUGH MAY BOTH BE ACTIVE ON WEDNESDAY. MINS BOTH NIGHTS WILL BE WELL ABOVE SEASONABLE NORMS...WITH WIDESPREAD MID 70S EXPECTED...AND SOME UPR 70S ON THE IMMEDIATE COAST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 300 AM MONDAY...FAIRLY TYPICAL JULY WEATHER WILL OCCUR THROUGH THE PERIOD...AND A DECENT JULY 4TH WEEKEND APPEARS TO BE SHAPING UP LOCALLY. BERMUDA HIGH PRESSURE WILL REMAIN WELL OFFSHORE BUT MAINTAIN RIDGING BACK TOWARDS THE EAST COAST. ALOFT...A BROAD TROUGH WILL FLATTEN LATE IN THE WEEK BEFORE SHARPENING ONCE AGAIN DURING THE UPCOMING WEEKEND. THE TROUGH AXIS IS PROGGED TO REMAIN WEST OF THE CAROLINAS HOWEVER...SO THIS WILL ACTUALLY DRIVE INCREASING THICKNESSES LOCALLY. THE COMBINATION OF THESE FEATURES WILL PUSH TEMPS INTO THE 90S...A FEW DEGREES ABOVE CLIMO...EACH AFTN...AND POSSIBLE WELL ABOVE CLIMO BY THE WEEKEND. MINS WILL ALSO BE WELL ABOVE NORMAL...MID 70S TO AROUND 80 EACH NIGHT THANKS TO THE CONTINUOUS WARM SW FLOW. TSTM CHANCES WILL EXIST EACH AFTN ALONG THE TYPICAL BOUNDARIES...AND AIDED BY THE SUBTLY LOWERED HEIGHTS ALOFT. BY THE WEEKEND...CONVECTION WILL DECREASE AS THE HEIGHTS BUILD OVERHEAD. WHILE IT IS TOO EARLY TO FOCUS ON DETAILS OF WHERE THE BEST POP WILL EXIST...THU/FRI WILL FEATURE BETTER CONVECTIVE CHANCES THAN EITHER SAT OR SUN. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 18Z...STILL EXPECT SOME LIGHT SHOWERS THIS AFTERNOON AS DIFFUSE FRONTAL BOUNDARY BUMP UP AGAINST THE SEA BREEZE BOUNDARY. THUNDER IS NOT OUT OF THE REALM OF POSSIBILITY...BUT REMOTELY SO. MAINLY A WEST WIND THIS AFTERNOON...STRONGEST ALONG THE COAST WITH MORE OF A WEST SOUTHWEST COMPONENT. DIMINISHING SOUTHWEST FLOW THIS EVENING WITH LITTLE OR NO FOG EXPECTED. THE NAM CONTINUES TO DEVELOP SHOWERS MONDAY AFTERNOON...BUT WITH LITTLE MOISTURE TO WORK WITH. COULD SEE AN MVFR CEILING AFTER THE SUN COMES UP. EXTENDED OUTLOOK...PREDOMINATELY VFR THROUGH TUESDAY. POSSIBLE AFTERNOON SHOWERS AND STORMS WEDNESDAY THROUGH FRIDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 145 PM MONDAY...SOUTHEAST WINDS CONTINUE ALONG THE NEAR SHORE WATERS AS THE SEA BREEZE CIRCULATION DEVELOPS THIS AFTERNOON. FARTHER OFF SHORE THE WINDS ARE LIGHT FROM THE WEST TO SOUTHWEST. OVERNIGHT SOUTHWEST WINDS WILL BECOME REESTABLISHED WITH SPEEDS OF 10 TO 15 KNOTS. SEAS OF 2 TO 4 FEET ARE EXPECTED OVERNIGHT. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 AM MONDAY...BERMUDA HIGH PRESSURE OFFSHORE AND A PIEDMONT TROUGH INLAND WILL DRIVE THE REGIME THROUGH MID-WEEK. THESE TWO FEATURES IN TANDEM WILL CREATE SW WINDS...WHICH WILL BE PREDOMINANTLY 10-15 KTS...BUT WILL LIKELY INCREASE EACH EVENING TO 20 KTS AS THE GRADIENT TIGHTENS THANKS TO THE DAILY SHARPENING OF THE PIEDMONT TROUGH. THE PERSISTENT SW FLOW AND LONG FETCH WILL CREATE A WAVE SPECTRUM COMPRISED OF BOTH SW WIND WAVE AND A GROWING SE SWELL. WAVE HEIGHTS OF 3-5 FT CAN BE EXPECTED THROUGH THE PERIOD...AND PERIODIC SCEC STATEMENTS MAY BE REQUIRED. LONG TERM /THURSDAY THROUGH FRIDAY/... AS OF 300 AM MONDAY...PERSISTENT BERMUDA HIGH PRESSURE AND PIEDMONT TROUGH WILL CONTINUE THROUGH THE EXTENDED IN A TYPICAL SUMMERTIME FASHION. THE GRADIENT WILL BECOME PINCHED AT TIMES DUE TO THE STRENGTH OF THESE FEATURES...ESPECIALLY IN THE EVENING AS THE PIEDMONT TROUGH SHARPENS INLAND FROM THE WATERS. THIS WILL DRIVE SW WINDS OF 10-15 KTS...RISING UP TO 20 KTS IN THE EVENING. SEAS WILL BE PREDOMINANTLY 3-5 FT...BUT SLIGHT INCREASES IN THE EVENINGS MAY NECESSITATE CAUTIONARY OR ADVISORY STATEMENTS AT TIMES. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...HAWKINS SHORT TERM...JDW LONG TERM...JDW AVIATION...DL
AREA FORECAST DISCUSSION
NWS NORMAN OK
1208 PM CDT MON JUN 29 2015 .AVIATION... LIGHT WINDS AND VFR CONDITIONS SHOULD PREVAIL THROUGHOUT THE TAF PERIOD. A WEAK FRONT IS ENTERING NORTHERN OKLAHOMA...WHICH WILL BRING MORE NORTHERLY...BUT STILL LIGHT...WINDS TO NORTHERN TAF SITES. SCATTERED SHOWERS AND STORMS MAY FORM OVER PARTS OF SOUTHERN OKLAHOMA THIS AFTERNOON AND EVENING...BUT CONFIDENCE IS NOT HIGH ENOUGH TO MENTION IN TAFS. MAD && .PREV DISCUSSION... /ISSUED 1004 AM CDT MON JUN 29 2015/ UPDATE... ADJUSTED PRECIP/WX THROUGH NOON... DISCUSSION... SCATTERED SHOWERS CONTINUE TO DISSIPATE ACROSS SWRN OK/NRN TX THIS MORNING AS MID-LEVEL SUPPORT FROM H850 WINDS CONTINUES TO WEAKEN. DID NOT MAKE ANY IMMEDIATE ADJUSTMENTS TO PRECIP/WX CHCS THIS AFTN. HOWEVER... WILL NEED TO KEEP AN EYE ON THE WEAK SHORT WAVE DROPPING SOUTH OFF THE WRN HIGH PLAINS OF CO/KS INTO THE PANHANDLES THIS AFTN. SKIES CONTINUE TO CLEAR QUICKLY BEHIND THE EXITING/DISSIPATING CONVECTION. SFC DPTS REMAIN IN THE MID/UPPER 60S ACROSS CENTRAL AND SRN OK... WITH SBCAPE VALUES POSSIBLE IN THE 800-1500 J/KG RANGE ACROSS SRN OK/NRN TX THIS EVENING. THE RECENT HRRR IS LIKELY CONTINUING TO OVER-DO CONVECTION... HOWEVER... THE GENERAL LOCATION IS LIKELY FAIRLY ACCURATE... WITH FOCUS ALONG THE WEAK/DIFFUSE SFC BOUNDARY ACROSS SRN OK. EXPECT SCATTERED SHOWERS/ISOLATED THUNDER TO DEVELOP LATE THIS AFTN... WITH MAYBE ONE OR TWO STORMS CAPABLE OF SOME STRONG WIND GUSTS. JTK PREV DISCUSSION... /ISSUED 632 AM CDT MON JUN 29 2015/ DISCUSSION... AVIATION DISCUSSION FOR THE 12Z TAFS IS BELOW. AVIATION... VFR CONDITIONS AND FAIRLY LIGHT WINDS ARE EXPECTED TO CONTINUE. ISO-SCT TSRA WILL AFFECT KLAW AND KHBR THROUGH 14Z BEFORE WEAKENING. ADDITIONAL ISO TSRA WILL FORM SOUTH OF KPPA-KSWO 18-05Z...BUT COVERAGE WILL BE TOO SPARSE TO MENTION IN THE TAFS. MBS PREV DISCUSSION... /ISSUED 329 AM CDT MON JUN 29 2015/ DISCUSSION... RAIN CHANCES AND HOT WEATHER OVER THE NEXT FEW DAYS ARE THE MAIN CONCERNS. THIS MORNING...ISOLATED TO SCATTERED THUNDERSTORMS HAVE FORMED ACROSS CENTRAL AND SOUTHWESTERN OKLAHOMA. A FEW FACTORS HAVE LED TO THE FORMATION OF THESE STORMS POSSIBLY INCLUDING A WEST TO SOUTHWESTERLY 850 MB JET...SLIGHT MID LEVEL WEAKNESS AND SLIGHT DECREASE IN MID LEVEL TEMPERATURES TO BREAK A WEAK CAP...AND SOME ELEVATED POTENTIAL INSTABILITY. THINK THESE STORMS WILL MOVE SOUTH THIS MORNING. NOT SURE IF THEY WILL WEAKEN. THINK THEY WILL STAY BELOW SEVERE LIMITS AND PRODUCE LOCALLY HEAVY RAINFALL AND FREQUENT LIGHTNING. ADDED/INCREASE RAIN CHANCES THIS MORNING MAINLY NEAR AND SOUTH OF I-40. THIS AFTERNOON AND EVENING...ADDITIONAL ISOLATED TO SCATTERED THUNDERSTORMS WILL OCCUR MAINLY OVER SOUTHERN OKLAHOMA AND NORTH TEXAS WHERE COOLEST 700 MB TEMPERATURES...SLIGHTLY DEEPER MOISTURE...AND WEAKEST CAPPING ARE FORECAST. CANNOT RULE OUT A STRAY SEVERE STORM WITH DAMAGING WINDS...BUT GENERALLY THINK WEAK SHEAR WILL LIMIT SEVERE POTENTIAL. LOCALLY HEAVY RAINFALL MAY BE POSSIBLE. STORMS WILL LIKELY DISSIPATE THROUGH THE NIGHT AS CAPPING STRENGTHENS. TODAY WILL BE HOT AND STAYED CLOSE TO MODEL HIGHS MAINLY IN THE MID 90S. HEAT INDICES ARE FORECAST TO STAY BELOW ADVISORY CRITERIA OF 105 DEGREES. TUESDAY AND WEDNESDAY...HOT WEATHER WILL PREVAIL WITH HIGHS WELL INTO THE 90S. SOME LOCATIONS WILL LIKELY EXCEED 100 DEGREES IN WESTERN AND NORTHERN OKLAHOMA AS WELL AS FAR WESTERN NORTH TEXAS. A HEAT ADVISORY MAY BE NECESSARY...MAINLY NEAR EAST OF A SHAWNEE TO MARIETTA LINE ON TUESDAY WHERE SURFACE DEWPOINT MAY POOL INTO THE LOWER TO MID 70S AND HEAT INDICES HAVE THE HIGHEST CHANCE OF EXCEEDING 105 DEGREES. CAPPING SHOULD BE STRONG ENOUGH FOR NO RAIN OR STORMS TUESDAY THROUGH WEDNESDAY MORNING. WEDNESDAY AFTERNOON THROUGH THURSDAY...A FEW SHOWERS AND THUNDERSTORMS MAY OCCUR AS A WEAK SURFACE BOUNDARY MOVES INTO THE AREA. CAPPING MAY BE QUITE STRONG WITH 700 MB TEMPERATURES +10 TO +13...SO THINK STORM COVERAGE WILL BE SPARSE AT BEST. A STRAY STRONG TO SEVERE STORM WITH LOCALLY HEAVY RAIN MAY OCCUR. THURSDAY WILL NOT BE QUITE AS HOT COMPARED TO TUESDAY AND WEDNESDAY. THURSDAY NIGHT THROUGH SUNDAY...RAIN CHANCES ARE FORECAST TO INCREASE OVER AREA DUE TO SOME MID/UPPER LEVEL TROUGHING. DON/T EXPECT ALL DAY RAINS...BUT HEAVY RAINFALL COULD OCCUR AT TIMES. WIDESPREAD SEVERE STORMS SEEM UNLIKELY DUE TO WEAK SHEAR. TEMPERATURES WILL BE A BIT COOLER. MBS && .PRELIMINARY POINT TEMPS/POPS... OKLAHOMA CITY OK 94 70 96 74 / 10 10 0 0 HOBART OK 96 69 98 73 / 30 20 0 0 WICHITA FALLS TX 96 72 97 75 / 60 20 0 0 GAGE OK 92 66 97 73 / 10 10 0 0 PONCA CITY OK 93 69 98 78 / 0 0 0 0 DURANT OK 95 71 95 72 / 20 20 10 10 && .OUN WATCHES/WARNINGS/ADVISORIES... OK...NONE. TX...NONE. && $$ 04/14/14
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
415 PM EDT MON JUN 29 2015 .SYNOPSIS... A WARM FRONT WILL MOVE NORTHEAST ACROSS THE STATE OVERNIGHT BRINGING SHOWERS TO PRIMARILY THE NORTHWEST HALF OF THE STATE. WARMER AND MORE UNSTABLE AIR WILL ENCOMPASS THE REGION TUESDAY HELPING TO TRIGGER NUMEROUS SHOWERS AND SCATTERED AFTERNOON THUNDERSTORMS AS A TROUGH OF LOW PRESSURE AT THE SURFACE AND ALOFT APPROACHES FROM THE WEST. EXPECT AN UNSETTLED WEATHER PATTERN TO PERSIST INTO THE UPCOMING HOLIDAY WEEKEND AS A BROAD BUT WEAKENING UPPER LEVEL TROUGH REMAINS POSITIONED OVER THE LOWER 48 EAST OF THE CONTINENTAL DIVIDE. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... WEAK SFC RIDGING HELPED TO PROVIDE A DRY AND PARTLY TO MOSTLY SUNNY DAY FOR THE REGION. THIS FAIR AND DRY WEATHER WILL CONTINUE THROUGH EARLY TONIGHT ACROSS THE EASTERN HALF OF THE STATE...WHILE CLOUDS QUICKLY INCREASE AND AREAS OF SHOWERS SPREAD ACROSS THE WESTERN MTNS BEFORE DUSK. 12Z OPER MODEL...LATEST 09Z SREF...AND HRRR CONSENSUS FAVORS A LIKELIHOOD OF SHOWERS OVER NW PA TONIGHT WITH MODEST QPF AMOUNTS IN THE 0.25 TO 0.50 INCH RANGE AS THE SFC LOW REACHES LAKE ERIE BY 12Z TUE AND IT/S ATTENDANT WARM FRONT LIFTS NE ACROSS THE REGION USHERING SLIGHTLY ABOVE NORMAL PWAT AIR. LOW TEMPS TONIGHT WILL VARY FROM THE U50S ACROSS THE NORTH...TO THE LOWER AND MID 60S ELSEWHERE. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/... THE LEAD SHORTWAVE IS FCST TO WEAKEN INTO THE LOWER GREAT LKS EARLY TUESDAY. HOWEVER...A DEEPENING MEAN TROUGH OVER THE OHIO RIVER VALLEY WILL HELP TO DEVELOP A SECONDARY SFC LOW ACROSS NRN INDIANA AND OHIO...AND SEND A FEW PULSES OF SHORTWAVE ENERGY EAST ACROSS PENN. THESE FEATURES WILL COMBINE WITH THE FORMATION OF A DISTINCT LEE TROUGH IN THE BLYR TO FOCUS NUMEROUS SHOWERS AND AFTERNOON TSRA ACROSS THE CENTRAL MTNS...THEN LATER IN THE AFTERNOON/EARLY EVENING MAINLY OVER THE SUSQ VALLEY. DEEP LAYER SHEAR VALUES WITHIN THIS CONVECTIVE ZONE ARE SUPPORTIVE OF ORGANIZED MULTI-CELL UPDRAFTS AND LINE SEGMENTS. A SECOND AREA OR A FEW NARROW BANDS OF LESS INTENSE SHRA/TSRA SHOULD BE FOUND ACROSS WESTERN PENN AND THE ALLEGHENIES LATER TUESDAY AFTERNOON AND EVENING...CLOSER TO THE SFC LOW AND MEAN UPPER TROUGH. SPC DAY 2 OUTLOOK HAS MAINTAINED A MARGINAL RISK FOR SVR TRSA ACROSS ALL OF THE CWA. BASED ON MDTLY STG...20 KT 0-1 KM SHEAR PROFILES ACROSS THE EASTERN ZONES TUES AFTERNOON...ALONG WITH POOLING OF LLVL MOISTURE RELATIVELY HIGHER ML CAPE AHEAD OF THE AFOREMENTIONED LEE TROUGH...A LATER UPGRADE TO SLIGHT RISK ACROSS THAT AREA MIGHT BE IN THE CARDS. TUESDAY WILL LIKELY OFFER THE GREATEST CHC FOR PRECIP UNTIL AT LEAST THURSDAY AFTERNOON AND EVENING. AFTER A VERY CHILLY AND RAINY WEEKEND...THE WARMTH AND SLIGHT MUGGINESS ON TUESDAY WITH DEWPOINTS 5-10F THAN THE ACTUAL DAYTIME TEMPS WE HAD SATURDAY WILL FEEL QUITE WELCOME. HIGH TEMPS TUESDAY AFTERNOON WILL BE IN THE L-M 70S ACROSS THE MTNS...AND AROUND 80F THROUGHOUT THE SUSQ VALLEY. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... THE LARGE UPPER LEVEL LOW OVER NORTHERN CANADA THAT WILL BE DOMINATING THE WEATHER PATTERN OVER THE NEXT WEEK WILL BRING A DEEPENING TROUGH THAT WILL CONTINUE TO ADVECT WARM MOIST SOUTHWESTERLY FLOW INTO THE REGION TUESDAY NIGHT INTO WEDNESDAY. MID LEVEL PERTURBATIONS AND SHORT WAVE TROUGHS SHOULD ENHANCE LAPSE RATES. DAY 2 OUTLOOK IS CURRENTLY MARGINAL FOR ALMOST ALL OF PENNSYLVANIA. SO EXPECT ANY TSTMS THAT FORM TUESDAY AFTERNOON INTO EVENING TO LINGER TUESDAY NIGHT INTO POSSIBLY WEDNESDAY. AS THE MAIN TROUGH LIFTS AND EXITS THE REGION WEDNESDAY THE CONVECTIVE ENVIRONMENT SHIFTS THE BEST INSTABILITY WITH LARGER VORTICIES DUE TO A SHORT WAVE THAT SHOULD ALLOW FOR LOW LVL LAPSE RATES TO BE STRONGER THROUGH ALONG A FRONTAL BOUNDARY. MODELS CONTINUING TO TREND MORE ZONAL FLOW LATE WEDNESDAY NIGHT INTO THURSDAY. WITH AN AMPLIFYING TROUGH SWINGING THROUGH THURSDAY AFTERNOON. THIS TREND SHOULD ALLOW FOR MORE A MORE SUMMERTIME REGIME THURSDAY INTO THE WEEKEND. IN THE WAKE OF THURSDAY/S TROUGH THE GFS/GEFS/EC BEGIN TO DIVERGE IN SOLUTIONS. HOWEVER WITH DRIER AIR ADVECTING IN AND THE CONSENSUS, THOUGH THE TIMING DIFFERS, THAT A RIDGE SHOULD BUILD OVER PA THROUGH THE FIRST HALF OF THE WEEKEND. THIS COULD LIMIT ANY CONVECTION TO ALONG THE MASON DIXON LINE AND ONLY A SLIGHT CHANCE FOR PRECIPITATION CURRENTLY SUNDAY EVENING. SO DESPITE A SERIES OF MID- LEVEL DISTURBANCES MOVING DOWNSTREAM FROM THE UPPER/MID MISSISSIPPI VALLEY THROUGH THE MID ATLC REGION...500MB HEIGHTS SHOULD BE IN RECOVERY MODE WHICH SHOULD ALLOW DAYTIME TEMPERATURES TO TREND WARMER INTO THE JULY 4TH HOLIDAY WEEKEND. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... ALL AIRFIELDS WILL STAY VRY WITH SCT-BKN CU FIELD BASES BETWEEN 3.5-4.5 KFT AGL FOR THE REST OF THIS AFTERNOON. CONDITIONS WILL LIKELY FALL INTO THE MVFR RANGE THIS EVENING ACROSS THE WRN MTNS AS A WARM FRONT AND LEADING EDGE OF INCREASING LLVL MOISTURE STREAMS NE FROM THE OHIO RIVER VALLEY. CONDITIONS WILL VARY BETWEEN MVFR AND VFR LATER TONIGHT THROUGH TUESDAY AS A FEW DISTURBANCE ALOFT AND SFC TROUGHS MOVE ACROSS THE REGION WITH A COUPLE ROUNDS OF SHOWERS/SCT TUESDAY AFTERNOON TSRA. AN UNSETTLED PATTERN WITH A SERIES OF FRONTS WILL BE AFFECTING THE REGION MUCH OF THIS WEEK. THE BEST CHANCES OF RESTRICTIONS WILL BE TUESDAY INTO WEDNESDAY. OUTLOOK... TUE-WED...MAINLY VFR...BUT SOME POSSIBLE RESTRICTIONS IN SHRA/TSRA. THU-FRI...AGAIN MAINLY VFR....BUT RESTRICTIONS POSSIBLE IN SHRA AND POSSIBLE TSRA. && .CLIMATE... JUNE 2015 HAS BEEN A WET MONTH ACROSS MUCH OF CENTRAL PA. THROUGH 6/28...OUR TWO LCD CLIMATE SITES /HARRISBURG AND WILLIAMSPORT/ ARE RANKED 8TH AND 6TH RESPECTIVELY FOR THE WETTEST JUNE ON RECORD. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT/STEINBUGL LONG TERM...CERU/STEINBUGL AVIATION...LAMBERT CLIMATE...
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
307 PM EDT MON JUN 29 2015 .SYNOPSIS... A WARM FRONT WILL MOVE NORTHEAST ACROSS THE STATE OVERNIGHT BRINGING SHOWERS TO PRIMARILY THE NORTHWEST HALF OF THE STATE. WARMER AND MORE UNSTABLE AIR WILL ENCOMPASS THE REGION TUESDAY HELPING TO TRIGGER NUMEROUS SHOWERS AND SCATTERED AFTERNOON THUNDERSTORMS AS A TROUGH OF LOW PRESSURE AT THE SURFACE AND ALOFT APPROACHES FROM THE WEST. EXPECT AN UNSETTLED WEATHER PATTERN TO PERSIST INTO THE UPCOMING HOLIDAY WEEKEND AS A BROAD BUT WEAKENING UPPER LEVEL TROUGH REMAINS POSITIONED OVER THE LOWER 48 EAST OF THE CONTINENTAL DIVIDE. && .NEAR TERM /THROUGH TONIGHT/... WEAK SFC RIDGING HELPED TO PROVIDE A DRY AND PARTLY TO MOSTLY SUNNY DAY FOR THE REGION. THIS FAIR AND DRY WEATHER WILL CONTINUE THROUGH EARLY TONIGHT ACROSS THE EASTERN HALF OF THE STATE...WHILE CLOUDS QUICKLY INCREASE AND AREAS OF SHOWERS SPREAD ACROSS THE WESTERN MTNS BEFORE DUSK. 12Z OPER MODEL...LATEST 09Z SREF...AND HRRR CONSENSUS FAVORS A LIKELIHOOD OF SHOWERS OVER NW PA TONIGHT WITH MODEST QPF AMOUNTS IN THE 0.25 TO 0.50 INCH RANGE AS THE SFC LOW REACHES LAKE ERIE BY 12Z TUE AND IT/S ATTENDANT WARM FRONT LIFTS NE ACROSS THE REGION USHERING SLIGHTLY ABOVE NORMAL PWAT AIR. LOW TEMPS TONIGHT WILL VARY FROM THE U50S ACROSS THE NORTH...TO THE LOWER AND MID 60S ELSEWHERE. && .SHORT TERM /TUESDAY/... THE LEAD SHORTWAVE IS FCST TO WEAKEN INTO THE LOWER GREAT LKS EARLY TUESDAY. HOWEVER...A DEEPENING MEAN TROUGH OVER THE OHIO RIVER VALLEY WILL HELP TO DEVELOP A SECONDARY SFC LOW ACROSS NRN INDIANA AND OHIO...AND SEND A FEW PULSES OF SHORTWAVE ENERGY EAST ACROSS PENN. THESE FEATURES WILL COMBINE WITH THE FORMATION OF A DISTINCT LEE TROUGH IN THE BLYR TO FOCUS NUMEROUS SHOWERS AND AFTERNOON TSRA ACROSS THE CENTRAL MTNS...THEN LATER IN THE AFTERNOON/EARLY EVENING MAINLY OVER THE SUSQ VALLEY. DEEP LAYER SHEAR VALUES WITHIN THIS CONVECTIVE ZONE ARE SUPPORTIVE OF ORGANIZED MULTI-CELL UPDRAFTS AND LINE SEGMENTS. A SECOND AREA OR A FEW NARROW BANDS OF LESS INTENSE SHRA/TSRA SHOULD BE FOUND ACROSS WESTERN PENN AND THE ALLEGHENIES LATER TUESDAY AFTERNOON AND EVENING...CLOSER TO THE SFC LOW AND MEAN UPPER TROUGH. SPC DAY 2 OUTLOOK HAS MAINTAINED A MARGINAL RISK FOR SVR TRSA ACROSS ALL OF THE CWA. BASED ON MDTLY STG...20 KT 0-1 KM SHEAR PROFILES ACROSS THE EASTERN ZONES TUES AFTERNOON...ALONG WITH POOLING OF LLVL MOISTURE RELATIVELY HIGHER ML CAPE AHEAD OF THE AFOREMENTIONED LEE TROUGH...A LATER UPGRADE TO SLIGHT RISK ACROSS THAT AREA MIGHT BE IN THE CARDS. TUESDAY WILL LIKELY OFFER THE GREATEST CHC FOR PRECIP UNTIL AT LEAST THURSDAY AFTERNOON AND EVENING. AFTER A VERY CHILLY AND RAINY WEEKEND...THE WARMTH AND SLIGHT MUGGINESS ON TUESDAY WITH DEWPOINTS 5-10F THAN THE ACTUAL DAYTIME TEMPS WE HAD SATURDAY WILL FEEL QUITE WELCOME. HIGH TEMPS TUESDAY AFTERNOON WILL BE IN THE L-M 70S ACROSS THE MTNS...AND AROUND 80F THROUGHOUT THE SUSQ VALLEY. && .LONG TERM /TUESDAY NIGHT THROUGH MONDAY/... THE SEVERE WEATHER RISK IS FCST TO SHIFT EWD ON D3/WED AS THE MAIN MID-LVL TROUGH EJECTS NEWD ACROSS THE UPPER OH VALLEY INTO UPSTATE NY/CENTRAL PA BY 18Z. THE CONVECTIVE ENVIRONMENT SHOULD BE SIMILAR TO D2 WITH THE AXIS OF BEST INSTABILITY/LOW LVL LAPSE RATES SHIFTED SLIGHTLY EWD INTO ERN PA. LOOK FOR ANOTHER ROUND OF TSTMS TO DEVELOP ALONG/AHEAD OF SFC COLD FRONT AND POSE AT LEAST A LOW RISK OF DAMAGING WINDS AND PERHAPS SOME HAIL. THE LATEST GLOBAL DETERMINISTIC MODELS AND ENSEMBLE MEANS ARE STARTING TO SUGGEST THAT THE HIGHLY AMPLIFIED RIDGE/TROUGH PATTERN OVER THE LOWER 48 WILL START TO FLATTEN OUT WITH TIME...PERHAPS REVERTING BACK TO A MORE TYPICAL SUMMERTIME MID- LATITUDE FLOW REGIME WITH THE MAIN BELT OF ZONAL WESTERLIES ALIGNED NEAR THE US/CANADIAN BORDER AND SUBTROPICAL RIDGING EXPANDING ACROSS THE SOUTHERN UNITED STATES. DESPITE A SERIES OF MID-LEVEL DISTURBANCES MOVING DOWNSTREAM OF THE WRN THROUGH FROM THE UPPER/MID MS VALLEY THROUGH THE MID ATLC REGION...500MB HEIGHTS SHOULD BE IN RECOVERY MODE WHICH SHOULD ALLOW DAYTIME TEMPERATURES TO TREND WARMER INTO THE JULY 4TH HOLIDAY WEEKEND. CONFIDENCE IN THE PCPN PATTERN REMAINS LOW ALTHOUGH THERE SEEMS TO BE SOME MODEL AGREEMENT IN FOCUSING RAINS THU/FRI ALONG THE D3/WEDNESDAY COLD FRONT...WHICH APPEARS TO BECOME QUASI-STNRY FROM SRN NJ WSWWD ALONG THE MASON DIXON LINE LATE THIS WEEK. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... ALL AIRFIELDS WILL STAY VRY WITH SCT-BKN CU FIELD BASES BETWEEN 3.5-4.5 KFT AGL FOR THE REST OF THIS AFTERNOON. CONDITIONS WILL LIKELY FALL INTO THE MVFR RANGE THIS EVENING ACROSS THE WRN MTNS AS A WARM FRONT AND LEADING EDGE OF INCREASING LLVL MOISTURE STREAMS NE FROM THE OHIO RIVER VALLEY. CONDITIONS WILL VARY BETWEEN MVFR AND VFR LATER TONIGHT THROUGH TUESDAY AS A FEW DISTURBANCE ALOFT AND SFC TROUGHS MOVE ACROSS THE REGION WITH A COUPLE ROUNDS OF SHOWERS/SCT TUESDAY AFTERNOON TSRA. AN UNSETTLED PATTERN WITH A SERIES OF FRONTS WILL BE AFFECTING THE REGION MUCH OF THIS WEEK. THE BEST CHANCES OF RESTRICTIONS WILL BE TUESDAY INTO WEDNESDAY. OUTLOOK... TUE-WED...MAINLY VFR...BUT SOME POSSIBLE RESTRICTIONS IN SHRA/TSRA. THU-FRI...AGAIN MAINLY VFR....BUT RESTRICTIONS POSSIBLE IN SHRA AND POSSIBLE TSRA. && .CLIMATE... JUNE 2015 HAS BEEN A WET MONTH ACROSS MUCH OF CENTRAL PA. THROUGH 6/28...OUR TWO LCD CLIMATE SITES /HARRISBURG AND WILLIAMSPORT/ ARE RANKED 8TH AND 6TH RESPECTIVELY FOR THE WETTEST JUNE ON RECORD. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LAMBERT NEAR TERM...LAMBERT SHORT TERM...LAMBERT/STEINBUGL LONG TERM...STEINBUGL AVIATION...LAMBERT CLIMATE...LAMBERT
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
1246 PM CDT MON JUN 29 2015 .AVIATION 18Z DISCUSSION... UPPER TROUGHING PATTERN TO REMAIN IN PLACE THROUGH THE TAF PD. TROUGH AMPLIFICATION IS EXPECTED BY 18Z. THUS...AN UNSETTLED PERIOD WITH AFT AND EVE SHOWERS AND TSTMS IS EXPECTED. SOME OVERNIGHT ACTIVITY MAY ALSO OCCUR AS AMPLIFICATION COMMENCES. WILL INCLUDE VCSH TO COVER THE LATENIGHT PERIOD. && .PREV DISCUSSION... /ISSUED 1022 AM CDT MON JUN 29 2015/ UPDATE... RADAR COVERAGE SHOWS MOST OF THE SHOWER ACTIVITY AHEAD OF A WEAK SURFACE FRONT SHOULD FAVOR THE SOUTHERN COUNTIES THIS MORNING...BUT SOME EXPANSION TO THE REST OF THE MID-STATE IS ANTICIPATED AS SUGGESTED BY HRRR OUTPUT THROUGH 00Z. THE KBNA SOUNDING FROM THIS MORNING SHOWS MOISTURE LIMITED TO THE 750MB- 550MB LAYER AND A PW VALUE OF ABOUT 1.4 INCHES...SO ISO TO SCT CONVECTION IS ANTICIPATED...WITH A MARGINAL RISK FOR SEVERE WEATHER PER SPC...WITH SOME BRIEF HEAVY DOWNPOURS AND OCCASIONAL LIGHTNING. PREV DISCUSSION... /ISSUED 625 AM CDT MON JUN 29 2015/ 12Z AVIATION UPDATE... VFR. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE IN THE FORECAST FOR THE DURATION OF THE TAF PERIOD. HIGHEST CHANCES WILL BE THIS AFTERNOON...AND HAVE VCTS IN THE FORECAST FOR THAT TIMEFRAME ATTM. IF THUNDERSTORMS PASS THROUGH TAF SITES...GUSTY WINDS AND REDUCED VISIBILITY FROM HEAVY RAINFALL MAY OCCUR. OTHERWISE...SOUTHWEST WINDS WILL PICK UP THIS MORNING TO AROUND 10 TO 15 KNOTS WITH GUSTS AROUND 20 KNOTS. WINDS SHOULD CALM DOWN LATE IN THE AFTERNOON OR EARLY EVENING BELOW 10 KNOTS. PREV DISCUSSION... /ISSUED 409 AM CDT MON JUN 29 2015/ DISCUSSION... SHOWERS AND A FEW EMBEDDED THUNDERSTORMS CONTINUE TO MOVE ACROSS MIDDLE TENNESSEE THIS EARLY MORNING. THIS WILL BE THE MAIN WEATHER FEATURE TODAY WITH THE BEST CHANCES FOR PRECIPITATION DURING THE MORNING HOURS ACROSS LOCATIONS WEST OF INTERSTATE 65 AND AFTERNOON HOURS ACROSS THE EAST. THINK HIGHS WILL HAVE TIME TO RECOVER FROM THE ADDITIONAL CLOUD COVER AND PRECIP ESPECIALLY WEST WITH MOST LOCATIONS A FEW DEGREES HIGHER THAN YESTERDAY WITH 80S EXPECTED. ANOTHER UPPER LEVEL IMPULSE WILL PUSH ACROSS THE AREA TONIGHT BRINGING ADDITIONAL CHANCES FOR PRECIPITATION. LOWS WILL FALL INTO THE MID TO UPPER 60S TONIGHT. WITH THE UPPER LEVEL TROUGH FIRMLY IN PLACE ACROSS THE GREAT LAKES REGION...THE FORECAST AREA WILL REMAIN IN MOSTLY NORTHWEST FLOW ALOFT ALLOWING SEVERAL UPPER LEVEL IMPULSES TO SPARK NUMEROUS CHANCES FOR STORMS THROUGH ALMOST THE ENTIRE FORECAST PERIOD. ZONAL FLOW FINALLY DEVELOPS BY THE END OF NEXT WEEKEND DECREASING CHANCES FOR RAIN. THE GOOD NEWS ON THAT FRONT IS THAT TEMPERATURES WILL REMAIN NEAR SEASONAL NORMALS WITH MOST LOCATIONS IN THE MID TO UPPER 80S THROUGH THE WEEK. BUT UNFORTUNATELY...WE WILL SAY GOODBYE TO THE LOWER DEWPOINTS WITH HUMID CONDITIONS RETURNING. PINPOINTING THE BEST CHANCES FOR SHOWERS AND THUNDERSTORMS WILL BE QUITE DIFFICULT SINCE TIMING AND STRENGTH OF THESE UPPER LEVEL IMPULSES WILL DEVIATE FROM DAY TO DAY. HOWEVER...MODELS HAVE BEEN FAIRLY CONSISTENT THAT WEDNESDAY NIGHT AND INTO THURSDAY LOOK TO HAVE THE BEST CHANCES FOR PRECIPITATION OUT OF THE ENTIRE FORECAST PERIOD. WITH THE FOURTH OF JULY WEEKEND AROUND THE CORNER... SHOWERS AND THUNDERSTORMS DO LOOK TO BE A POSSIBILITY...BUT THINK THE AREA WILL BE TRANSITIONING TO MORE OF A DIURNAL CONVECTION PATTERN OF MOSTLY AFTERNOON AND EVENING STORMS. DEFINITELY SOMETHING TO WATCH ESPECIALLY IF YOU HAVE ANY OUTDOOR PLANS THIS UPCOMING WEEKEND. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 86 69 88 68 / 30 40 50 30 CLARKSVILLE 85 68 86 68 / 30 30 50 40 CROSSVILLE 81 66 81 65 / 30 30 60 50 COLUMBIA 86 68 87 68 / 30 40 50 30 LAWRENCEBURG 86 69 86 68 / 30 40 50 30 WAVERLY 85 69 87 69 / 30 30 50 30 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 21
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
230 PM CDT MON JUN 29 2015 .SHORT TERM...(TONIGHT AND TUESDAY) ISSUED AT 230 PM CDT MON JUN 29 2015 UPPER LEVEL SHORTWAVE TOUGH DROPPING SOUTHWARD ACROSS THE REGION THIS AFTERNOON...PROVIDING MUCH OF THE FORCING FOR THE ONGOING SHOWERS AND THUNDERSTORMS. AROUND 2000 J/KG SBCAPE ALONG AND WEST OF THE MISSISSIPPI RIVER VIA THE RAP TO HELP POWER THE STORMS. HOWEVER...RAP/HRRR BUFKIT SOUNDINGS CONTINUE TO PAINT A SKINNY CAPE PROFILE...NOT SUPPORTIVE OF STRONG UPDRAFTS. SHEAR IS A BIT BETTER COMPARED TO YESTERDAY...BUT STILL RELATIVELY MEAGER. RAP PEGS 0-6KM SHEAR AT 20-25 KTS...MOST OF WHICH IS IN THE 0-3 KM LAYER. WITH A RELATIVELY DRY SUB CLOUD LAYER...EXPECT SOME ENHANCED WIND GUSTS WITH THE STRONGER STORMS. COULD SEE SOME LARGE HAIL...BUT A BUNCH OF PEA TO 1/2 INCH SIZE MIGHT BE MORE LIKELY. WIND GUSTS UP TO 40-45 KTS ALSO LOOKS REASONABLE. CAN/T RULE OUT SOMETHING HIGHER IF BOWING SEGMENTS START DEVELOPING. MESO MODELS WERE A BIT BEHIND ON THE DEVELOPMENT/SPEED OF THE CONVECTION...BUT TRENDS AND LATER RUNS FAVOR CLEARING THE BULK OF PRECIPITATION SOUTH/EAST OF THE FORECAST AREA BY 03Z. MAIN STRONG-SEVERE THREAT WOULD BE THROUGH 7-8 PM. THE UPPER LEVEL TROUGH TAKES A RIGHT TURN AS IT GETS THROUGH THE FORECAST AREA LATER TONIGHT...TAKING AIM AT THE EASTERN GREAT LAKES. SHOULD PROVIDE ENOUGH FORCING FOR MORE SHOWERS/STORMS ACROSS EASTERN WI...AND DEPENDING ON SPEED OF THE SYSTEM...COULD LINGER INTO WESTERN WI IN THE MORNING. WILL CONTINUE SOME SMALL POPS LATE OVERNIGHT/EARLY TUE MORNING TO ACCOUNT FOR THIS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 230 PM CDT MON JUN 29 2015 MODELS IN GOOD AGREEMENT WITH A GRADUAL BREAKDOWN OF THE AMPLIFIED WEST COAST RIDGE...RESULTING IN A CHANGE FROM NORTHWEST FLOW TO MORE ZONAL FOR THE WEEKEND. GFS/ECMWF/GEM ALSO IN FAVOR OF SHUNTING ANY RIPPLES ON THE FLOW SOUTH/NORTH...TRENDING TOWARD A DRY STRING OF DAYS. EVEN WED...WHICH MODELS HAVE BEEN BOUNCING BACK AND FORTH ON WHETHER TO SPIN A SHORTWAVE ACROSS THE REGION...NOW SUGGEST THE SFC HIGH WILL WIN OUT...KEEPING THAT PIECE OF ENERGY SOUTHWEST. SOME SMALL RAIN CHANGES MAY CREEP IN A FEW DAYS BASED ON THE CONSENSUS SOLUTION...BUT OVERALL...IT LOOKS MORE DRY THAN NOT FROM WED INTO THE WEEKEND. MONDAY SHOWS SOME POTENTIAL FOR A STORMY DAY...WITH A COLD FRONT DROPPING ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1233 PM CDT MON JUN 29 2015 FOCUS IS ON POSSIBLE SEVERE THUNDERSTORMS THIS AFTERNOON AS A MID- LEVEL TROUGH DROPS THROUGH THE REGION. MAINLY VFR CONDITIONS EXPECTED BETWEEN THUNDERSTORMS...DETERIORATING INTO IFR TEMPORARILY IN THE 21-23Z TIME FRAME. ALSO...WATCH FOR STRONG MICROBURST TYPE WINDS WITH THESE STORMS. LOOK FOR THE CONVECTION TO CLEAR SOUTHEAST OF THE KRST/KLSE TAF SITES AROUND 01-02Z. LOOKS LIKE STRATUS/FOG WITH SETUP UP AGAIN EARLY TUESDAY MORNING...SIMILAR TO THIS MORNING. LOOKING FOR KRST TO SLIP INTO IFR AFTER 07Z AND KLSE AROUND 09Z. PLAN ON IMPROVEMENT INTO VFR RANGE AGAIN AFTER 14Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...RIECK LONG TERM....RIECK AVIATION.....DAS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1233 PM CDT MON JUN 29 2015 .UPDATE... ISSUED AT 1233 PM CDT MON JUN 29 2015 CONFIDENCE IS INCREASING FOR A BOUT OF SEVERE WEATHER THIS AFTERNOON INTO EARLY THIS EVENING OR APPROXIMATELY 2-8PM TIME FRAME. WATER VAPOR SHOWING THE CULPRIT...A MID- LEVEL SHORTWAVE TROUGH...DROPPING SOUTHEAST ACROSS THE ARROWHEAD OF MN EARLY THIS AFTERNOON. AS OF THIS WRITING...STRONG TO SEVERE STORMS WERE ALREADY ONGOING ACROSS FAR NORTHERN WI INTO NORTHEAST WI. A COUPLE 1 INCH HAIL REPORTS CAME OUT OF THE DULUTH MN NWS OFFICE. MAIN SEVERE THREAT ACROSS OUR AREA CONTINUES TO BE LARGE HAIL OF AROUND AN INCH TO POSSIBLY GOLF BALL SIZE. SECONDARY THREAT WILL BE MICROBURST TYPE WINDS OF 40-50 MPH GIVEN INVERTED-V TYPE SOUNDING BEING DEPICTED BY THE NAM/RAP MODELS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 312 AM CDT MON JUN 29 2015 LATEST WATER VAPOR SATELLITE IMAGERY SHOWS UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES AND UPPER LEVEL RIDGE OVER THE WESTERN UNITED STATES INTO THE CANADIAN ROCKIES. SEVERAL PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT PER WATER VAPOR SATELLITE IMAGERY. ONE IMPULSE WAS PRODUCING SHOWERS OVER CENTRAL AND SOUTHWEST WISCONSIN PER KARX RADAR. DUE TO MOIST BOUNDARY LAYER AND MOSTLY CLEAR SKIES PATCHY FOG HAS DEVELOPED OVER PARTS OF THE FORECAST AREA. MAIN FORECAST CONCERNS TODAY INTO THIS EVENING ARE PRECIPITATION CHANCES. THE 29.00Z GFS/NAM INDICATE NEXT SHORTWAVE TROUGH NEAR LAKE WINNIPEG TO IMPACT THE FORECAST AREA THIS AFTERNOON INTO THIS EVENING. THE 29.00Z GFS/NAM SHOW PV ADVECTION IN THE 500-300MB LAYER/STEEP LOW LEVEL LAPSE RATES/INSTABILITY WITH SHORTWAVE TROUGH. THE LATEST HIGH RESOLUTION MODELS...ARW/NMM/HRRR...SHOW DIFFERENCES IN TIMING OF THE CONVECTION INTO THE FORECAST AREA TODAY INTO THIS EVENING. THE 29.00Z DETERMINISTIC AND HIGH RESOLUTION MODELS SUGGEST CONVECTION WILL DEVELOP MID TO LATE THIS AFTERNOON AND CONTINUE INTO THE EVENING HOURS ACROSS MUCH OF THE FORECAST AREA. HAVE TRENDED THE HIGHER PRECIPITATION CHANCES AFTER 21Z TODAY TO 03Z TUESDAY. THE NEXT CONCERN ARE SEVERE POSSIBILITIES. THE 29.00Z GFS/NAM/RAP SHOW UP TO 20 KNOTS OF 0-3KM SHEAR AND BUFKIT SOUNDINGS INDICATE MANLY STRAIGHT HODOGRAPHS THROUGH THIS LAYER LATE THIS AFTERNOON/THIS EVENING MAINLY WEST OF THE MISSISSIPPI RIVER. THE 29.00Z GFS/NAM AND 29.03Z RAP BUILD UP TO 2000 J/KG OF SURFACE BASE CAPE ACROSS THE FORECAST AREA. WITH WEAK SHEAR IN THE 0-3KM LAYER...LARGE HAIL WILL BE A POSSIBILITY WITH SOME OF THE STRONGER THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 312 AM CDT MON JUN 29 2015 WEAK SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND SHORTWAVE ENERGY PUSHES INTO SOUTHERN/EASTERN WISCONSIN TUESDAY. WITH THE 29.00Z GFS/NAM SUGGEST STEEP LOW LEVEL LAPSE RATE AND THE BETTER INSTABILITY OVER THE EASTERN FORECAST AREA...SMALL PRECIPITATION CHANCES CONTINUE TO BE WARRANTED OVER THIS AREA. THE 29.00Z GFS/NAM/ECMWF ARE TRENDING A FARTHER WESTWARD SOLUTION WITH THE PIECES OF ENERGY EMBEDDED IN THE NORTHWESTERLY FLOW ALOFT WEDNESDAY INTO WEDNESDAY NIGHT. PLUS...SURFACE RIDGE BUILDS INTO NORTHERN MINNESOTA AND NORTHERN WISCONSIN AND DEVELOP A DRIER NORTHEASTERLY FLOW INTO THE FORECAST AREA. HAVE REDUCE PRECIPITATION CHANCES ACROSS THE WESTERN PORTIONS OF THE FORECAST AREA...BASED ON THE DRIER NORTHEASTERLY FLOW AND WESTERN SHIFT OF THE SHORTWAVE ENERGY. MAIN FORECAST CONCERNS THURSDAY INTO SUNDAY ARE PRECIPITATION CHANCES THROUGH THE PERIOD. THE 29.00Z GFS/ECMWF/GEM ARE IN AGREEMENT IN WEAKENING UPPER LEVEL TROUGH OVER THE GREAT LAKES REGION/EASTERN UNITED STATES AND DEVELOP WEST TO EAST ZONAL FLOW ALOFT BY 12Z SUNDAY ACROSS THE NORTHERN TIER STATES. THE BIGGEST DIFFERENCE BETWEEN THE 29.00Z GFS/ECMWF/GEM IS TIMING OF THE INDIVIDUAL IMPULSES INTO THE GREAT LAKES REGION THROUGH THE FORECAST PERIOD. THE 29.00Z MODELS SUGGEST ENOUGH LIFT/FORCING/MOISTURE CONVERGENCE WITH THE IMPULSES. WILL CONTINUE TREND OF PERIODIC SMALL PRECIPITATION CHANCES THROUGH MUCH OF THE FORECAST PERIOD. TEMPERATURES WILL REMAIN SLIGHTLY BELOW OR NEAR NORMAL DURING THE FORECAST PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1233 PM CDT MON JUN 29 2015 FOCUS IS ON POSSIBLE SEVERE THUNDERSTORMS THIS AFTERNOON AS A MID-LEVEL TROUGH DROPS THROUGH THE REGION. MAINLY VFR CONDITIONS EXPECTED BETWEEN THUNDERSTORMS...DETERIORATING INTO IFR TEMPORARILY IN THE 21-23Z TIME FRAME. ALSO...WATCH FOR STRONG MICROBURST TYPE WINDS WITH THESE STORMS. LOOK FOR THE CONVECTION TO CLEAR SOUTHEAST OF THE KRST/KLSE TAF SITES AROUND 01-02Z. LOOKS LIKE STRATUS/FOG WITH SETUP UP AGAIN EARLY TUESDAY MORNING...SIMILAR TO THIS MORNING. LOOKING FOR KRST TO SLIP INTO IFR AFTER 07Z AND KLSE AROUND 09Z. PLAN ON IMPROVEMENT INTO VFR RANGE AGAIN AFTER 14Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...DAS SHORT TERM...DTJ LONG TERM....DTJ AVIATION...DAS