Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 06/23/15


AREA FORECAST DISCUSSION
NWS PUEBLO CO
1106 PM MDT SAT JUN 20 2015 .UPDATE... ISSUED AT 842 PM MDT SAT JUN 20 2015 UPDATED TO END SHOWERS AND THUNDERSTORMS ACROSS THE AREA FOR THE REMAINDER OF THE NIGHT. RADAR AND SATELLITE INDICATE A COUPLE OF SHOWERS STILL OVER THE SAN JUAN RANGE...BUT HAVE QUICKLY BEEN DISSIPATING AND SHOULD COME TO AN END BY 10 PM. NO OTHER UPDATES AT THIS TIME. MOZLEY && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 256 PM MDT SAT JUN 20 2015 WEAK COLD FRONT WHICH PUSHED THROUGH THE PLAINS EARLIER TODAY HAS BROUGHT E-NE WINDS AND SLIGHTLY COOLER TEMPS TO THE PLAINS/ERN MOUNTAINS...WHILE TEMPS FARTHER WEST OVER THE MOUNTAINS AND INTERIOR VALLEYS REMAIN LITTLE CHANGED. LOW LEVEL MOISTURE/INSTABILITY LOOK SUFFICIENT FOR SOME ISOLATED TSRA OVER THE ERN MOUNTAINS...THOUGH LACK OF ANY TRIGGER AND FAIRLY SUBSTANTIAL CIN HAS SO FAR KEPT THINGS IN CHECK. LAST COUPLE RUNS OF THE NAM STILL HAVE SOME WEAK TSRA DEVELOPING...WHILE HRRR AND OTHER MESOSCALE MODELS ARE MAINLY DRY. WILL KEEP JUST SOME VERY LOW POPS FOR A FEW OF THE HIGHER PEAKS INTO EARLY EVENING...THOUGH WOULD NOT BE TOO SURPRISED TO SEE AREA REMAIN CONVECTION FREE AT THIS POINT. ANY CLOUDS WILL CLEAR QUICKLY AFTER SUNSET...WITH OVERNIGHT LOWS JUST SLIGHTLY COOLER THAN SAT MORNING MOST LOCATIONS. ON SUNDAY...HEIGHTS BUILD SLIGHTLY AND WITH PRESSURE FALLS OVER THE PLAINS PRODUCING A RETURN TO S-SW WINDS...EXPECT ALL AREAS TO BECOME VERY HOT ONCE AGAIN...WITH READINGS NEAR/OVER 100F ACROSS THE LOWER ARK VALLEY. AIR MASS LOOKS TOO DRY TO SUPPORT ANY CONVECTION...SO WILL KEEP A DRY FORECAST GOING ALL AREAS THROUGH THE AFTERNOON. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 256 PM MDT SAT JUN 20 2015 SUNDAY NIGHT AND MONDAY...STRONG UPPER RIDGE WILL BRING MAINLY DRY AND HOT WEATHER ACROSS THE CWA. THERE WILL ONLY BE A VERY SLIGHT CHANCE FOR LATE AFTERNOON AND EVENING HIGH BASED CONVECTION OVER THE EASTERN PART OF THE AREA. HIGH TEMPERATURES WILL RANGE FROM 90 TO 100 ACROSS THE I-25 CORRIDOR AND SOUTHEAST PLAINS...70S AND 80S HIGH VALLEYS...AND 60S AND 70S MOUNTAINS. TUESDAY AND WEDNESDAY...UPPER RIDGE PUSHES EAST SOME...ALLOWING A FETCH OF MODEST MOISTURE TO ENTER THE AREA. IN ADDITION...A SURFACE BOUNDARY WILL BE IN THE VICINITY OF THE EASTERN PLAINS...SO ISOLATED TO SCATTERED PRECIPITATION WILL BE EVIDENT DURING THE AFTERNOON AND EVENING HOURS. MODELS DIVERGENT ON HOW MUCH CONVECTION WILL BE ACROSS THE EAST TUESDAY EVENING. GFS HAS THE MOST...WITH EUROPEAN BARELY ANY. THERE IS THE POTENTIAL FOR A FEW SEVERE STORMS BOTH DAYS WITH INSTABILITY VALUES INCREASING. WITH SOME CLOUD COVER...TEMPERATURES WILL BE A LITTLE LOWER THAN OVER THE WEEKEND. THURSDAY THROUGH SUNDAY...UPPER RIDGE FORECAST TO BUILD TO OUR WEST DURING THE PERIOD. GFS SHOWS A SHORTWAVE RIDING DOWN THE NORTHEAST SIDE OF THE RIDGE IN THE THURSDAY TO FRIDAY TIME FRAME...MORE SO THAN THE EUROPEAN. THERE WILL LIKELY BE DIURNAL SHOWERS AND STORMS EACH DAY WITH NORTHWEST FLOW ALOFT ON THE FRONT SIDE OF THE RIDGE....MORE CONCENTRATED ACROSS THE EASTERN HALF OF THE CWA. HIGH TEMPERATURES WILL BE NEAR SEASONAL AVERAGES...IN THE 80S AND 90S PLAINS...70S AND 80S HIGH VALLEYS AND 50S TO 70S MOUNTAINS. -TLM- && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1105 PM MDT SAT JUN 20 2015 VFR CONDITIONS AT ALL THREE TERMINALS THROUGH THE NEXT 24 HOURS. A FEW AFTERNOON WIND GUSTS TO NEAR 25 KTS ARE POSSIBLE AT KCOS ON SUNDAY AFTERNOON. MOZLEY && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MOZLEY SHORT TERM...PETERSEN LONG TERM...TM AVIATION...MOZLEY
AREA FORECAST DISCUSSION
NWS NEW YORK NY
806 PM EDT MON JUN 22 2015 .SYNOPSIS... A COLD FRONT MOVES THROUGH THE REGION TUESDAY EVENING. HIGH PRESSURE BUILDS IN BEHIND THE FRONT TUESDAY NIGHT AND REMAINS INTO WEDNESDAY. THE HIGH WEAKENS THURSDAY AS IT SLIDES OFFSHORE. A PROLONGED PERIOD OF UNSETTLED WEATHER IS THEN POSSIBLE AS SEVERAL WAVES OF LOW PRESSURE TRACK NEAR THE AREA FROM THURSDAY NIGHT INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... NO SIGNIFICANT CHANGES TO THE FORECAST FOR THIS EVENING. MOST OF THE SHOWERS/TSTMS ARE WELL UPSTREAM...MOVING INTO WESTERN NY/PA...AND ANY SHOWERS/TSTMS PREVIOUSLY INDICATED ON HRRR FOR THE EARLY EVENING HOURS HAVE NOT DEVELOPED YET. THEREFORE...WILL GO AHEAD AND REMOVE MENTION OF POPS FOR EARLY THIS EVENING...AND THEN WILL CARRY SLIGHT CHANCE POPS FOR MAINLY FAR NW ZONES FOR LATE TONIGHT AND INTO DAYBREAK TUESDAY AS WARM FRONT APPROACHES. SW FLOW WILL RESULT IN INCREASING HUMIDITY LEVELS TONIGHT WITH WARM AND MUGGY CONDS. MIN TEMPS WILL GENERALLY BE IN THE MID TO UPPER 60S INLAND...AND 70 TO 75 ALONG THE COAST. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/... DEPARTING MCS ACROSS NEW ENGLAND WILL COMPLICATE FORECAST SOME FOR TUESDAY AHEAD OF AN APPROACHING COLD FRONT...AS MOSTLY CLOUDY SKIES COULD BE PRESENT FOR THE FIRST PART OF THE DAY...IN ADDITION TO A FEW LINGERING SHOWERS/T-STORMS EARLY AS THE WARM FRONT LIFTS NORTH. BY LATE MORNING...EXPECT BREAKS IN CLOUDS AND GUSTY SW FLOW TO PUSH TEMPS TO AROUND OR JUST ABOVE 90 IN NYC...LOWER 90S ACROSS NE NJ AND MID TO UPPER 80S ELSEWHERE. HEAT INDICES WILL PEAK AROUND 95 IN NYC AND IN THE UPPER 90S IN NE NJ...AND AROUND 90 ELSEWHERE. THIS WILL GENERATE MODERATE INSTABILITY AHEAD OF THE COLD FRONT...WITH MODEL FCST CAPES OF NEAR OR JUST ABOVE 2000 J/KG ESPECIALLY JUST INLAND. AFTER A SEVERAL HOUR BREAK MID DAY...THE FRONT WILL BEGIN TO TOUCH OFF SCATTERED SHOWERS/T-STORMS WHICH WILL PROGRESS FROM NW TO SE ACROSS THE REGION BEGINNING INLAND DURING THE EARLY-MID AFTERNOON. GIVEN THE INSTABILITY IN PLACE AND 40-50 KT OF 0-6 KM SHEAR FORECAST BY THE MODELS...SEVERE T-STORMS ARE FORECAST...WITH THE STORM PREDICTION CENTER PLACING THE ENTIRE REGION IN A SLIGHT RISK. WHILE AN ISOLATED TORNADO CANNOT BE RULED OUT...DAMAGING WINDS AND PERHAPS SOME LARGE HAIL APPEAR TO BE THE MAIN THREATS. COLD FRONT AND ASSOCIATED T-STORMS WILL PUSH SE OF THE REGION DURING THE EARLY EVENING HOURS TUESDAY WITH CLEARING BEHIND THE FRONT. A DRIER AIRMASS WILL BE USHERED INTO THE REGION AS WELL WITH LOWERING HUMIDITY. THERE WILL BE A MODERATE RISK OF RIP CURRENTS AT OCEAN BEACHES ON TUESDAY. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... 12Z MODEL SUITE IS IN GOOD AGREEMENT WITH MAINLY ZONAL H5 FLOW THROUGH FRI NIGHT. DIFFERENCES BEGIN TO TAKE SHAPE STARTING SAT WITH A TROUGH DIGGING FROM THE UPPER MIDWEST THROUGH THE SE STATES THROUGH EARLY NEXT WEEK. THERE IS DISAGREEMENT WITH BOTH TIMING AND AMPLITUDE OF THE TROUGH...WHICH IS LEADING TO VARIATIONS IN THE TRACK OF SEVERAL WAVES OF LOW PRES AT THE SFC DURING THIS TIME. WED WILL BE A DRIER AND MUCH MORE COMFORTABLE DAY WITH HIGH PRES BUILDING TOWARDS THE AREA AND DEWPOINTS IN THE MID 50S. SUNNY SKIES WITH HIGHS IN THE LOWER TO MID 80S ARE EXPECTED. CLOUDS WILL BEGIN TO INCREASE ON THU AS THE HIGH MOVES OFFSHORE AND WEAKENS. THE FIRST IN A SERIES OF WAVES WILL APPROACH THE AREA THU NIGHT INCREASING THE CHANCES FOR RAIN. THIS LOW PASSES S OF LONG ISLAND ON FRI FOLLOWED BY A FEW MORE THROUGH THE WEEKEND. THIS WILL LEAD TO A PERIOD OF UNSETTLED WEATHER WITH CLOUDS...PERIODS OF RAIN/DRIZZLE AND ONSHORE FLOW RESULTING IN COOLER THAN NORMAL CONDS INTO EARLY NEXT WEEK. AS OF RIGHT NOW CONSENSUS IS TRACKING ALL OF THE WAVES TO THE S OF LONG ISLAND...THEREFORE HAVE REMOVES ALL MENTION OF THUNDER AS WE`LL BE ON THE STABLE SIDE. TEMPS START OFF NEAR NORMAL WED AND THU...THEN WILL BE BELOW NORMAL THROUGH THE WEEKEND. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... HIGH PRESSURE MOVES OFFSHORE AND GIVES WAY TO A WARM FRONT PASSING NORTH OF THE REGION LATE TONIGHT AND A COLD FRONT THAT WILL APPROACH DURING THE DAY TUE. MAINLY VFR MUCH OF THE PERIOD. ONLY POSSIBILITY FOR MVFR OR LOWER ASSOCIATED WITH SHOWERS LATE TONIGHT MAINLY NEAR KSWF BUT THIS IS ONLY A SLIGHT CHANCE AS WELL AS HIGHER CHANCES FOR SHOWER AND THUNDERSTORM DEVELOPMENT ALONG AND AHEAD OF THE COLD FRONT MID AFTN TUE INTO EARLY TUE EVE. A GENERAL S FLOW 5-10 KT FOR TONIGHT INCREASES TUE AND BECOMES GUSTY FOR CITY TERMINALS WITH GUSTS REACHING 20-25 KT. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. KLGA FCSTER COMMENTS: AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. KEWR FCSTER COMMENTS: AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. KTEB FCSTER COMMENTS: SHIFT TO SW COULD BE OFF BY AN HOUR OR TWO EARLY THIS EVENING. AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. KHPN FCSTER COMMENTS: AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. KISP FCSTER COMMENTS: AMENDMENTS LIKELY TO REFINE TIMING OF SHOWERS AND THUNDERSTORMS TUE...WHICH COULD VARY 1-3 HRS COMPARED TO FORECAST. .OUTLOOK FOR 00Z WED THROUGH SAT... .TUE NIGHT...SHOWERS/TSTMS ENDING EARLY. VFR RETURNING. WINDS BECOME NW-N 5-10 KT. .WED...VFR. WNW GUSTS UP TO 20KT PM. WINDS DIMINISH AT NIGHT. .THU...VFR AM. CHC LATE DAY/NIGHTTIME SHRA/SUB-VFR. .FRI-SAT...PERIODS OF RAIN WITH SUB-VFR POSSIBLE. && .MARINE... TRANQUIL CONDS TONIGHT...AND THEN SW FLOW INCREASES AHEAD OF AN APPROACHING COLD FRONT. SW WINDS WILL GUST TO 25-30 KT AND SEAS WILL BUILD TO 4-6 FT ON THE OCEAN TUESDAY AFTERNOON AND THROUGH TUESDAY EVENING...WHILE 25-30 KT GUSTS WILL DEVELOP ON NY HARBOR/SOUTH SHORE BAYS IN THE AFTERNOON THROUGH AROUND SUNSET. WILL ADD THE SOUTH SHORE BAYS TO THE SCA FOR THE AFTERNOON/EARLY EVENING. POTENTIAL ON ALL WATERS FOR VARIABLE/GUSTY WINDS LATE TUESDAY AFTERNOON AND EVENING AS T-STORMS MOVE THROUGH. SUB-ADVSY CONDS ARE EXPECTED THROUGH AT LEAST THU WITH A WEAK PRES GRADIENT ACROSS THE WATERS. UNCERTAINTY WITH THE TRACK OF A WAVE OF LOW PRES BEGINS THU NIGHT AND WINDS/SEAS COULD BUILD TO SCA LEVELS QUICKER THAN FORECAST. CURRENTLY...THEY ARE NOT EXPECTED UNTIL FRI EVE. && .HYDROLOGY... TSTMS TUE COULD POSE AN ISOLD FLASH FLOOD THREAT...HOWEVER PRIMARILY MINOR FLOODING IS EXPECTED ATTM. THERE IS A CHANCE FOR SEVERAL ROUNDS OF WIDESPREAD RAINFALL FROM THU THROUGH SUN...ALTHOUGH DIFFERENCES IN THE EXACT TRACKS OF THE WAVES OF LOW PRES ARE UNCERTAIN WHICH WILL DETERMINE AMOUNTS. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY FROM NOON TUESDAY TO 2 AM EDT WEDNESDAY FOR ANZ350-353-355. SMALL CRAFT ADVISORY FROM NOON TO 8 PM EDT TUESDAY FOR ANZ338- 345. && $$ SYNOPSIS...JMC NEAR TERM...MPS/GS SHORT TERM...GS LONG TERM...24 AVIATION...JM MARINE...GS HYDROLOGY...GS
AREA FORECAST DISCUSSION
NWS ALBANY NY
505 PM EDT SUN JUN 21 2015 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE REGION TONIGHT. HIGH PRESSURE WILL BRIEFLY BUILD IN LATE TONIGHT AND MONDAY. A LOW PRESSURE WILL APPROACH THE REGION MONDAY NIGHT AND CROSS THE LOCAL AREA ON TUESDAY ACCOMPANIED BY SHOWERS AND THUNDERSTORMS AND BREEZY CONDITIONS. HIGH PRESSURE WILL BUILD BACK IN FOR THE MIDDLE OF THE WEEK. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... HAVE SHOWERS ALONG WITH ISOLATED THUNDERSTORMS OCCURRING ACROSS THE FORECAST AREA AT THIS TIME. THERE HAS BEEN LIMITED LIGHTNING WITH THE ACTIVITY AND IT HAS BEEN MAINLY IN CLOUD. THE HRRR SEEMS TO HAVE A GOOD HANDLE ON THE ACTIVITY. DESPITE INSTABILITY TO WORK WITH LAPSE RATES ARE RATHER WEAK SO IT`S LIMITING STORM GROWTH. OVERALL WIND FIELD WILL STRENGTHEN AS WE HEAD INTO THE EVENING HOURS HOWEVER THE INSTABILITY WILL THEN BE ON THE DECREASE. THE NEXT COUPLE/FEW HOURS ARE OUR BEST CHANCES FOR THUNDERSTORMS. HAVE REMOVED THE ENHANCED WORDING FROM THE FORECAST SINCE THERE IS ONLY A VERY LOW PROBABILITY OF ANY THUNDERSTORM REACHING SEVERE LEVELS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/... FAIR WEATHER IS EXPECTED FOR MONDAY AS RIDGING AT THE SURFACE AND ALOFT BUILDS IN LATE TONIGHT AND MONDAY. THIS RIDGING WILL BE SHORT LIVED AS WE REMAIN IN A FAST FLOW. ANOTHER SHORT WAVE TROUGH AND LOW PRESSURE WILL BE IN THE APPROACH MONDAY AND WILL MOVE ACROSS THE REGION TUESDAY. THE SYSTEM WILL BE MORE POTENT AND WILL BRING BETTER CHANCES FOR SHOWERS AND THUNDERSTORMS TO THE REGION. THE STORM PREDICTION CENTER AS THE FORECAST AREA UNDER A SLIGHT RISK FOR SEVERE THUNDERSTORMS. THE MODEL HAVE TRENDED A BIT FASTER WITH THE TIMING OF THE SYSTEM...LOOKING AT A THREAT WINDOW FROM LATE MORNING INTO MID AFTERNOON. EXPECTING LARGE SCALE ASCENT AS THE TROUGH APPROACHES AND STRONG DEEP-LAYER SHEAR TO BE PRESENT. THE BETTER CHANCES FOR STRONG TO POSSIBLY SEVERE STORMS WOULD BE SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE THE GREATER INSTABILITYAND STEEPER LAPSE RATES ARE FORECAST. HAVE THREAT FOR SEVERE THUNDERSTORMS IN OUR HAZARDOUS WEATHER OUTLOOK. IN ADDITION...PWATS WILL INCREASE TO 1.5 TO 2 INCHES SO STORMS WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD CAUSE LOCALIZED FLOODING OF URBAN...POOR DRAINAGE AND LOW LYING AREAS. IT WILL BECOME BREEZY AHEAD OF THE SYSTEM`S COLD IN THE WARM SECTOR WITH THE SOUTHERLY FLOW AND IN THE WAKE OF THE COLD FRONT WITH THE WESTERLY FLOW WITH GUSTS OF 30 TO 40 MPH. A RETURN TO FAIR WEATHER FOR TUESDAY NIGHT WITH BRISK WINDS SUBSIDING. MONDAY WILL BE SEASONABLE WARM WHILE IT WILL GET VERY WARM/HOT ON TUESDAY. HIGHS TUESDAY ARE FORECAST TO BE IN THE MAINLY FROM THE MID 70S TO LOWER 80S ACROSS THE HIGHER TERRAIN WITH MID TO UPPER 80S IN THE VALLEY. DID NOT GO WITH THE WARMER MET NUMBERS...SEEMS OVERDONE. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... THE FIRST 36 HOURS OF THE EXTENDED WILL BE DRY...BUT WAVES OF LOW PRESSURE WILL TRAVERSE THE OHIO VALLEY AND MID-ATLANTIC...BRINGING A CHANCE FOR SHOWERS AND THUNDERSTORMS FOR THE REMAINDER OF THE PERIOD. BUT TEMPERATURES WILL RUN COOLER THAN NORMAL...WITH HIGHS WEDNESDAY AND THURSDAY RANGING FROM THE UPPER 60S TO LOWER 80S... AND HIGH FRIDAY THROUGH SUNDAY IN ONLY THE 60S AND LOWER TO MID 70S. LOWS WILL BE MOSTLY IN THE UPPER 40S AND THE 50S. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/... A LOW PRESSURE SYSTEM WILL MOVE NORTH OF THE REGION THIS AFTERNOON...AS THE COLD FRONT WILL MOVE THROUGH EARLY THIS EVENING. HIGH PRESSURE WILL BRIEFLY RIDGE IN LATE TONIGHT INTO MONDAY. CONDITIONS HAVE IMPROVED TO HIGH MVFR/VFR AT KALB SOUTH TO KPOU EARLY THIS AFTERNOON...BUT CIGS STILL REMAIN IN THE LOW MVFR RANGE AT KPSF/KGFL /1.5-2.O KFT AGL/. WE EXPECT THE CIGS TO IMPROVE TO VFR LEVELS BTWN 18Z-21Z AT ALL THE TAF SITES. HOWEVER...SCT SHOWERS AND SOME ISOLD THUNDERSTORMS WILL INCREASE AHEAD OF AN UPPER-LEVEL DISTURBANCE...AND A COLD FRONT FOR THE LATE PM/EARLY EVENING. THE SHOWERS MAY REDUCE CIGS/VSBYS TO MVFR LEVELS...ESPECIALLY AT KGFL/KPSF/KPOU BTWN 22Z-01Z. CONFIDENCE WAS NOT GREAT ENOUGH FOR THUNDER TO BE ADDED TO THE TAFS. VCSH GROUPS WERE USED AT KALB THROUGHOUT...AND AT THE OTHER TAF SITES PRIOR TO 22Z. THE FRONT MOVES THROUGH BTWN 01Z/MON TO 04Z/MON ACROSS ERN NY AND WRN NEW ENGLAND. THE CLOUDS MAY QUICKLY CLEAR...AND THE RESIDUAL LOW-LEVEL MOISTURE WITH LIGHT WINDS COUPLED WITH THE WET GROUND MAY ALLOW FOR SOME MIST/FOG AND STRATUS TO FORM IN THE IFR/LOW MVFR RANGE AT KGFL/KPSF BTWN 06Z-13Z. KPOU MAY HAVE ENOUGH OF A WIND FOR ONLY SOME PATCHY MVFR MIST. KALB WINDS MAY CONTINUE THROUGHOUT THE NIGHT FOR NO MIST/FOG AND STRATUS. ANY FOG OR STRATUS SHOULD DISSIPATE QUICKLY BTWN 12Z-14Z/MON WITH VFR CONDITIONS RETURNING AT ALL THE TAF SITES. THE WINDS WILL BE FROM THE NW/N AT 5-12 KTS IN THE WAKE OF THE WAVE ASSOCIATED WITH BILLS MOISTURE. THE WINDS WILL BACK TO SW TO W AHEAD OF THE COLD FRONT...AND THEN VEER BACK TO W TO NW AT 5-10 KTS BEFORE BECOMING LIGHT TO CALM ESPECIALLY AT KGFL...AND PERHAPS KPOU SHORTLY AFTER 04Z. THE WINDS WILL BE FROM THE W TO NW AT 5-10 KTS LATE TOMORROW MORNING INTO THE AFTERNOON. OUTLOOK... MON NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. TUE: HIGH OPERATIONAL IMPACT. BREEZY. LIKELY SHRA...TSRA. TUE NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX. WED-THU: NO OPERATIONAL IMPACT. NO SIG WX. THU NIGHT-FRI: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. && .FIRE WEATHER... A COLD FRONT WILL MOVE ACROSS THE REGION TONIGHT. HIGH PRESSURE WILL BRIEFLY BUILD IN LATE TONIGHT AND MONDAY. A LOW PRESSURE WILL APPROACH THE REGION MONDAY NIGHT AND CROSS THE LOCAL AREA ON TUESDAY ACCOMPANIED BY SHOWERS AND THUNDERSTORMS AND BREEZY CONDITIONS. HIGH PRESSURE WILL BUILD BACK IN FOR THE MIDDLE OF THE WEEK. && .HYDROLOGY... A WIDESPREAD RAINFALL OCCURRED ACROSS THE AREA SATURDAY NIGHT INTO SUNDAY MORNING WITH THE HIGHEST TOTAL OF 1 TO 2 INCHES WERE ACROSS THE EASTERN CATSKILLS AND MID HUDSON VALLEY. ADDITIONAL RAINFALL WITH OCCUR WITH THE CONVECTION INTO EARLY THIS EVENING. OUR NEXT CHANCES FOR RAINFALL WILL COME TUESDAY AS A LOW PRESSURE SYSTEM CROSSES THE AREA ON TUESDAY. PWATS WILL INCREASE TO 1.5 TO 2 INCHES SO STORMS WILL BE CAPABLE OF PRODUCING HEAVY DOWNPOURS WHICH COULD CAUSE LOCALIZED FLOODING OF URBAN...POOR DRAINAGE AND LOW LYING AREAS. 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...IAA NEAR TERM...IAA SHORT TERM...IAA LONG TERM...ELH AVIATION...WASULA FIRE WEATHER...IAA HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
213 AM EDT SUN JUN 21 2015 .SYNOPSIS... THE REMNANTS OF TROPICAL STORM BILL WILL IMPACT THE REGION TONIGHT INTO SUNDAY BRINGING A MODERATE TO HEAVY RAINFALL TO AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT. A LOW PRESSURE SYSTEM WILL APPROACH THE REGION TONIGHT AND MOVE ACROSS THE AREA SUNDAY AND SUNDAY NIGHT TRIGGERING SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON INTO THE EVENING HOURS. SOME THUNDERSTORMS MAYBE STRONG TO POSSIBLY SEVERE TO THE NORTH AND WEST OF THE CAPITAL DISTRICT. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1230 AM EDT...RADAR CONTINUES TO SHOW WIDESPREAD LIGHT TO MODERATE RAIN FOR MOST AREAS NEAR AND SOUTH OF INTERSTATE 90...ALONG WITH EMBEDDED POCKETS OF HEAVIER RAIN. IN FACT...SOME CG LIGHTNING STRIKES HAVE BEEN NOTED ACROSS PORTIONS OF NORTHERN ULSTER CO. THE REMNANTS OF TC BILL PASSING TO THE SOUTH WILL COMBINE WITH THE RETURN FLOW AROUND A DEPARTING HIGH TO HELP PWATS RISE. THEY ARE EXPECTED TO INCREASE TO 1 1/2+ INCHES ACROSS THE FORECAST AREA WITH AROUND 2 INCHES ACROSS THE SOUTHERN MOST PORTION AS THE REMNANTS OF BILL MOVE ACROSS THE MID ATLANTIC REGION TOWARD THE NEW YORK METROPOLITAN AREA FOR LATER TONIGHT. THE NEW 00Z NAM...AS WELL AS THE 3KM HRRR GUIDANCE...ALL SUGGEST STEADY AND HEAVIER RAINFALL WILL CONTINUE TO OVERSPREAD OUR REGION OVER THE NEXT SEVERAL HOURS...AS THE LOW PASSES SOUTH OF THE AREA...AND SOME OF THE HEAVIER PRECIP OVER PA STARTS TO ROTATE TOWARDS SOUTHERN PORTIONS OF THE REGION. THIS WILL ESPECIALLY BE TRUE FOR AREAS FROM THE CAPITAL REGION ON SOUTHWARD. RAINFALL LOOKS TO BE FAIRLY STEADY THROUGH DAYBREAK...AND MAY BE LOCALLY HEAVY...ESPECIALLY FOR FAR SOUTHERN AREAS. CANNOT RULE OUT ADDITIONAL RUMBLES OF THUNDER IN A FEW SPOTS DUE TO SOME SMALL AMOUNTS OF ELEVATED INSTABILITY IN PLACE AS WELL. NO FLOOD WATCH HAS BEEN ISSUED SINCE RAIN RATES WON/T APPEAR TO EXCEED FLASH FLOOD GUIDANCE. STILL...SOME PONDING OF WATER ON ROADWAYS AND IN URBAN AND LOW LYING AREAS MAY STILL OCCUR IN A FEW LOCATIONS...AND THIS WILL CONTINUE TO BE HIGHLIGHTED IN THE HWO STATEMENT. THIS RAINFALL WILL BE HELPING ACROSS THESE SOUTHERN AND EASTER AREAS...AS THE ANNUAL DEPARTURE FROM NORMAL FOR POUGHKEEPSIE NY STANDS AT -7.62 INCHES AND IS PITTSFIELD MA -4.18 INCHES. OVERNIGHT LOWS WILL MAINLY BE IN THE 60S...ALONG WITH THE MUGGY AND CLOUDY CONDITIONS. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... THE REMNANTS OF BILL ARE EXPECTED TO TRACK TO ACROSS THE NEW YORK METRO AREA AND LONG ISLAND AND WILL CONTINUE TO IMPACTS MAINLY THE AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT THROUGH THE MORNING INTO THE EARLY AFTERNOON HOURS. A SHORT WAVE TROUGH AND LOW PRESSURE SYSTEM MOVING THROUGH THE FAST ZONAL FLOW WILL BE ON THE APPROACH FOR SUNDAY. THE SYSTEM`S WARM FRONT IS EXPECTED TO LIFT ACROSS THE REGION SUNDAY PLACING US IN THE WARM SECTOR. THE AMOUNT OF INSTABILITY IS THE BIG QUESTION. FLOW WILL BE UNIDIRECTIONAL WITH SHEAR INCREASING AS THE AFTERNOON PROGRESSES INTO THE EVENING HOURS. IF THERE IS ENOUGH INSTABILITY TO WORK MULTICELLS CLUSTERS SHOULD FORM. HOWEVER GUIDANCE IS NOT IN AGREEMENT ABOUT HOW STEEP THE LAPSE RATES SHOULD GET. THE STORM PREDICTION CENTER HAS UPGRADED THE SEVERE WEATHER RISK TO SLIGHT FOR MUCH OF EAST CENTRAL NEW YORK...FOR AREAS TO THE NORTH AND WEST OF THE CAPITAL DISTRICT...WITH THE REST OF THE FORECAST AREA UNDER A MARGINAL RISK. HAVE ENHANCED WORDING IN THE FORECAST FOR GUSTY WINDS...SMALL HAIL AND HEAVY RAINFALL ADDRESSING THE THREAT. CHANCES FOR STORMS WILL DECREASE OVERNIGHT SUNDAY INTO MONDAY AS THE SHORT WAVE MOVES OFF TO OUR EAST. SOME RIDGING WILL BRIEFLY BUILD IN BETWEEN SHORT WAVES RESULTING IN MAINLY FAIR WEATHER WITH SEASONABLE TEMPERATURES MONDAY. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THIS WILL BE A PREDOMINANTLY WET PERIOD WITH MAINLY SEASONABLE TEMPERATURES. THE ONLY DRY PERIOD IS EXPECTED TO RUN FROM TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THERE WILL BE PERIODS OF SUNSHINE... BUT ASIDE FROM TUESDAY...INSTABILITY AND MOISTURE WILL BE LIMITED...SO THE MENTION IS FOR JUST SHOWERS. HIGH TEMPERATURES WILL START OFF TUESDAY FROM AROUND 70 DEGREES IN THE WESTERN ADIRONDACKS...TO THE UPPER 80S IN THE LOWER MID HUDSON VALLEY...BUT WILL GRADUALLY COOL DOWN...TO HIGHS RANGING FROM THE MID 60S TO MID 70S BY FRIDAY. SATURDAY WILL AVERAGE ONLY SLIGHTLY WARMER. TUESDAY NIGHT WILL BE MILDEST...WITH LOWS FROM THE MID 50S TO LOWER 60S. BY FRIDAY NIGHT...LOWS WILL RANGE FROM AROUND 50 DEGREES IN THE NORTHERN HIGH PEAKS...TO THE UPPER 50S IN THE MID HUDSON VALLEY. NORMAL HIGHS AND LOWS FOR ALBANY DURING THIS PERIOD ARE LOWER 80S AND AROUND 59 DEGREES...RESPECTIVELY. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... FLYING CONDITIONS WILL BE MVFR/IFR THROUGH 09Z AS PLENTY OF LOW- LEVEL MOISTURE AND RAIN SHOWERS MOVE ACROSS THE REGION. FLYING CONDITIONS ARE EXPECTED TO BE PREDOMINATELY MVFR VISIBILITIES...WITH PREDOMINATELY IFR CEILINGS DUE TO LOW STRATUS. HAVE PLACED TEMPO GROUPS AT THE TAF SITES FROM 06Z TO 09Z FOR BRIEF IFR VISIBILITY REDUCTIONS ASSOCIATED WITH HEAVY RAIN SHOWERS. LATEST RADAR TRENDS INDICATE RAIN WILL CONTINUE TO BECOME MORE OF A SHOWERY NATURE...BEFORE TAPERING OFF BETWEEN BY AROUND 10Z TO 14Z. WINDS OVERNIGHT WILL BE SOUTHEAST...BUT LIGHT AROUND 4-8 KNOTS. FLYING CONDITIONS SHOULD IMPROVE ABOVE IFR AFTER 12Z AS SHOWERS END...BUT IT MAY TAKE UNTIL THE MID TO LATE MORNING FOR FLYING CONDITIONS TO RETURN TO ABOVE MVFR LEVELS. DURING THE MID TO LATE AFTN HOURS...THERE MAY BE SOME ADDITIONAL SHOWERS OR T-STORMS AROUND...BUT THESE WILL BE RATHER SCATTERED IN NATURE. SOUTHERLY WINDS WILL EVENTUALLY BECOME WESTERLY AROUND 10 KTS. OUTLOOK... SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA...TSRA. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... THE REMNANTS OF TROPICAL STORM BILL WILL IMPACT THE REGION TONIGHT INTO SUNDAY BRINGING A MODERATE TO HEAVY RAINFALL TO AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT. A LOW PRESSURE SYSTEM WILL APPROACH THE REGION TONIGHT AND MOVE ACROSS THE AREA SUNDAY AND SUNDAY NIGHT TRIGGERING SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON INTO THE EVENING HOURS. CONDITIONS DRY OUT FOR MONDAY...HOWEVER MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY. && .HYDROLOGY... PWATS WILL BE IN THE RISE AND ARE EXPECTED TO INCREASE TO 1 1/2+ INCHES ACROSS THE FORECAST AREA WITH AROUND 2 INCHES ACROSS THE SOUTHERN MOST PORTION AS THE REMNANTS OF BILL MOVE ACROSS THE MID ATLANTIC REGION TOWARD THE NEW YORK METROPOLITAN AREA. THE GUIDANCE HAS TRENDED A BIT NORTHWARD WITH THE HEAVIER QPF. THE GFS IS THE MOST AGGRESSIVE HOWEVER IT APPEARS TO BE HAVING CONVECTIVE FEEDBACK ISSUES AND CAN BE TRUSTED. A MODERATE TO HEAVY RAINFALL IS EXPECTED TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT AS THE HIGHER PWATS ARRIVE. NO FLOOD WATCH HAS BEEN ISSUED. THE SOUTHEASTERN PORTION OF THE FORECAST UNDER THE SEVERE DROUGHT CATEGORY ON THE U.S. DROUGHT MONITOR. THE ANNUAL DEPARTURE FROM NORMAL FOR POUGHKEEPSIE NY STANDS AT -7.62 INCHES AND IS PITTSFIELD MA -4.18 INCHES. SOME URBAN AND POOR DRAINING FLOODING IS POSSIBLE. PWATS WILL DECREASE SOME SUNDAY AS THE REMNANTS OF BILL MOVE AWAY FROM THE REGION. HOWEVER A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA SUNDAY TRIGGERING SHOWERS AND THUNDERSTORMS. THE FOCUS FOR THIS ACTIVITY WILL BE MAINLY TO THE NORTH AND WEST OF THE CAPITAL DISTRICT SUNDAY AFTERNOON INTO THE EVENING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH SOME THUNDERSTORMS. CONDITIONS DRY OUT FOR MONDAY...HOWEVER MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY. 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...IAA NEAR TERM...IAA/FRUGIS/KL SHORT TERM...IAA LONG TERM...ELH AVIATION...IRL FIRE WEATHER...IAA HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1233 AM EDT SUN JUN 21 2015 .SYNOPSIS... THE REMNANTS OF TROPICAL STORM BILL WILL IMPACT THE REGION TONIGHT INTO SUNDAY BRINGING A MODERATE TO HEAVY RAINFALL TO AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT. A LOW PRESSURE SYSTEM WILL APPROACH THE REGION TONIGHT AND MOVE ACROSS THE AREA SUNDAY AND SUNDAY NIGHT TRIGGERING SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON INTO THE EVENING HOURS. SOME THUNDERSTORMS MAYBE STRONG TO POSSIBLY SEVERE TO THE NORTH AND WEST OF THE CAPITAL DISTRICT. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1230 AM EDT...RADAR CONTINUES TO SHOW WIDESPREAD LIGHT TO MODERATE RAIN FOR MOST AREAS NEAR AND SOUTH OF INTERSTATE 90...ALONG WITH EMBEDDED POCKETS OF HEAVIER RAIN. IN FACT...SOME CG LIGHTNING STRIKES HAVE BEEN NOTED ACROSS PORTIONS OF NORTHERN ULSTER CO. THE REMNANTS OF TC BILL PASSING TO THE SOUTH WILL COMBINE WITH THE RETURN FLOW AROUND A DEPARTING HIGH TO HELP PWATS RISE. THEY ARE EXPECTED TO INCREASE TO 1 1/2+ INCHES ACROSS THE FORECAST AREA WITH AROUND 2 INCHES ACROSS THE SOUTHERN MOST PORTION AS THE REMNANTS OF BILL MOVE ACROSS THE MID ATLANTIC REGION TOWARD THE NEW YORK METROPOLITAN AREA FOR LATER TONIGHT. THE NEW 00Z NAM...AS WELL AS THE 3KM HRRR GUIDANCE...ALL SUGGEST STEADY AND HEAVIER RAINFALL WILL CONTINUE TO OVERSPREAD OUR REGION OVER THE NEXT SEVERAL HOURS...AS THE LOW PASSES SOUTH OF THE AREA...AND SOME OF THE HEAVIER PRECIP OVER PA STARTS TO ROTATE TOWARDS SOUTHERN PORTIONS OF THE REGION. THIS WILL ESPECIALLY BE TRUE FOR AREAS FROM THE CAPITAL REGION ON SOUTHWARD. RAINFALL LOOKS TO BE FAIRLY STEADY THROUGH DAYBREAK...AND MAY BE LOCALLY HEAVY...ESPECIALLY FOR FAR SOUTHERN AREAS. CANNOT RULE OUT ADDITIONAL RUMBLES OF THUNDER IN A FEW SPOTS DUE TO SOME SMALL AMOUNTS OF ELEVATED INSTABILITY IN PLACE AS WELL. NO FLOOD WATCH HAS BEEN ISSUED SINCE RAIN RATES WON/T APPEAR TO EXCEED FLASH FLOOD GUIDANCE. STILL...SOME PONDING OF WATER ON ROADWAYS AND IN URBAN AND LOW LYING AREAS MAY STILL OCCUR IN A FEW LOCATIONS...AND THIS WILL CONTINUE TO BE HIGHLIGHTED IN THE HWO STATEMENT. THIS RAINFALL WILL BE HELPING ACROSS THESE SOUTHERN AND EASTER AREAS...AS THE ANNUAL DEPARTURE FROM NORMAL FOR POUGHKEEPSIE NY STANDS AT -7.62 INCHES AND IS PITTSFIELD MA -4.18 INCHES. OVERNIGHT LOWS WILL MAINLY BE IN THE 60S...ALONG WITH THE MUGGY AND CLOUDY CONDITIONS. && .SHORT TERM /6 AM THIS MORNING THROUGH MONDAY NIGHT/... THE REMNANTS OF BILL ARE EXPECTED TO TRACK TO ACROSS THE NEW YORK METRO AREA AND LONG ISLAND AND WILL CONTINUE TO IMPACTS MAINLY THE AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT THROUGH THE MORNING INTO THE EARLY AFTERNOON HOURS. A SHORT WAVE TROUGH AND LOW PRESSURE SYSTEM MOVING THROUGH THE FAST ZONAL FLOW WILL BE ON THE APPROACH FOR SUNDAY. THE SYSTEM`S WARM FRONT IS EXPECTED TO LIFT ACROSS THE REGION SUNDAY PLACING US IN THE WARM SECTOR. THE AMOUNT OF INSTABILITY IS THE BIG QUESTION. FLOW WILL BE UNIDIRECTIONAL WITH SHEAR INCREASING AS THE AFTERNOON PROGRESSES INTO THE EVENING HOURS. IF THERE IS ENOUGH INSTABILITY TO WORK MULTICELLS CLUSTERS SHOULD FORM. HOWEVER GUIDANCE IS NOT IN AGREEMENT ABOUT HOW STEEP THE LAPSE RATES SHOULD GET. THE STORM PREDICTION CENTER HAS UPGRADED THE SEVERE WEATHER RISK TO SLIGHT FOR MUCH OF EAST CENTRAL NEW YORK...FOR AREAS TO THE NORTH AND WEST OF THE CAPITAL DISTRICT...WITH THE REST OF THE FORECAST AREA UNDER A MARGINAL RISK. HAVE ENHANCED WORDING IN THE FORECAST FOR GUSTY WINDS...SMALL HAIL AND HEAVY RAINFALL ADDRESSING THE THREAT. CHANCES FOR STORMS WILL DECREASE OVERNIGHT SUNDAY INTO MONDAY AS THE SHORT WAVE MOVES OFF TO OUR EAST. SOME RIDGING WILL BRIEFLY BUILD IN BETWEEN SHORT WAVES RESULTING IN MAINLY FAIR WEATHER WITH SEASONABLE TEMPERATURES MONDAY. && .LONG TERM /TUESDAY THROUGH SATURDAY/... THIS WILL BE A PREDOMINANTLY WET PERIOD WITH MAINLY SEASONABLE TEMPERATURES. THE ONLY DRY PERIOD IS EXPECTED TO RUN FROM TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. THERE WILL BE PERIODS OF SUNSHINE... BUT ASIDE FROM TUESDAY...INSTABILITY AND MOISTURE WILL BE LIMITED...SO THE MENTION IS FOR JUST SHOWERS. HIGH TEMPERATURES WILL START OFF TUESDAY FROM AROUND 70 DEGREES IN THE WESTERN ADIRONDACKS...TO THE UPPER 80S IN THE LOWER MID HUDSON VALLEY...BUT WILL GRADUALLY COOL DOWN...TO HIGHS RANGING FROM THE MID 60S TO MID 70S BY FRIDAY. SATURDAY WILL AVERAGE ONLY SLIGHTLY WARMER. TUESDAY NIGHT WILL BE MILDEST...WITH LOWS FROM THE MID 50S TO LOWER 60S. BY FRIDAY NIGHT...LOWS WILL RANGE FROM AROUND 50 DEGREES IN THE NORTHERN HIGH PEAKS...TO THE UPPER 50S IN THE MID HUDSON VALLEY. NORMAL HIGHS AND LOWS FOR ALBANY DURING THIS PERIOD ARE LOWER 80S AND AROUND 59 DEGREES...RESPECTIVELY. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... FLYING CONDITIONS HAVE LOWERED DOWN TO MVFR CONDITIONS FOR CIGS FOR ALL SITES DUE TO ABUNDANT LOW LEVEL MOISTURE CAUSING PLENTY OF LOW STRATUS TO FORM. OVER THE NEXT FEW HOURS...RAIN SHOWERS WILL SPREAD ACROSS THE REGION FROM THE WEST. THIS WILL DROP VSBYS DOWN TO MVFR LEVELS AS WELL...AND EVENTUALLY IFR CONDITIONS FOR BOTH VSBYS/CIGS BY AROUND MIDNIGHT OR SO. THIS WILL CONTINUE THROUGH THE REMAINDER OF THE OVERNIGHT HOURS...WITH LIGHT TO CALM WINDS. SHOWERS WILL TAPER OFF BY AROUND 6-9 AM OVER THE REGION. IFR CONDITIONS SHOULD END ONCE THE RAIN STOPS...BUT IT MAY TAKE UNTIL THE MID TO LATE MORNING FOR FLYING CONDITIONS TO RETURN TO ABOVE MVFR LEVELS. DURING THE MID TO LATE AFTN HOURS...THERE MAY BE SOME ADDITIONAL SHOWERS OR T-STORMS AROUND...BUT THESE WILL BE RATHER SCT IN NATURE. SOUTHERLY WINDS WILL EVENTUALLY BECOME WESTERLY AROUND 10 KTS OR SO. OUTLOOK... SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. LIKELY SHRA...TSRA. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. TUESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...TSRA. TUESDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. WEDNESDAY: NO OPERATIONAL IMPACT. NO SIG WX. WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. && .FIRE WEATHER... THE REMNANTS OF TROPICAL STORM BILL WILL IMPACT THE REGION TONIGHT INTO SUNDAY BRINGING A MODERATE TO HEAVY RAINFALL TO AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT. A LOW PRESSURE SYSTEM WILL APPROACH THE REGION TONIGHT AND MOVE ACROSS THE AREA SUNDAY AND SUNDAY NIGHT TRIGGERING SHOWERS AND THUNDERSTORMS MAINLY DURING THE AFTERNOON INTO THE EVENING HOURS. CONDITIONS DRY OUT FOR MONDAY...HOWEVER MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY. && .HYDROLOGY... PWATS WILL BE IN THE RISE AND ARE EXPECTED TO INCREASE TO 1 1/2+ INCHES ACROSS THE FORECAST AREA WITH AROUND 2 INCHES ACROSS THE SOUTHERN MOST PORTION AS THE REMNANTS OF BILL MOVE ACROSS THE MID ATLANTIC REGION TOWARD THE NEW YORK METROPOLITAN AREA. THE GUIDANCE HAS TRENDED A BIT NORTHWARD WITH THE HEAVIER QPF. THE GFS IS THE MOST AGGRESSIVE HOWEVER IT APPEARS TO BE HAVING CONVECTIVE FEEDBACK ISSUES AND CAN BE TRUSTED. A MODERATE TO HEAVY RAINFALL IS EXPECTED TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT AS THE HIGHER PWATS ARRIVE. NO FLOOD WATCH HAS BEEN ISSUED. THE SOUTHEASTERN PORTION OF THE FORECAST UNDER THE SEVERE DROUGHT CATEGORY ON THE U.S. DROUGHT MONITOR. THE ANNUAL DEPARTURE FROM NORMAL FOR POUGHKEEPSIE NY STANDS AT -7.62 INCHES AND IS PITTSFIELD MA -4.18 INCHES. SOME URBAN AND POOR DRAINING FLOODING IS POSSIBLE. PWATS WILL DECREASE SOME SUNDAY AS THE REMNANTS OF BILL MOVE AWAY FROM THE REGION. HOWEVER A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE AREA SUNDAY TRIGGERING SHOWERS AND THUNDERSTORMS. THE FOCUS FOR THIS ACTIVITY WILL BE MAINLY TO THE NORTH AND WEST OF THE CAPITAL DISTRICT SUNDAY AFTERNOON INTO THE EVENING. LOCALLY HEAVY RAINFALL WILL BE POSSIBLE WITH SOME THUNDERSTORMS. CONDITIONS DRY OUT FOR MONDAY...HOWEVER MORE SHOWERS AND THUNDERSTORMS ARE EXPECTED TUESDAY. 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...IAA NEAR TERM...IAA/FRUGIS/KL SHORT TERM...IAA LONG TERM...ELH AVIATION...FRUGIS FIRE WEATHER...IAA HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1124 AM EDT SUN JUN 21 2015 .SYNOPSIS... THE REMNANTS OF TROPICAL DEPRESSION BILL WILL CONTINUE TO LIFT NORTHEAST AWAY FROM THE REGION TODAY. A WEAK COLD FRONT FOLLOWS TONIGHT WITH A STRONGER COLD FRONT EXPECTED TO SWING THROUGH OUR REGION LATE TUESDAY. A COMPLEX FRONTAL SYSTEM WILL AFFECT THE MID ATLANTIC STATES LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH THE REMNANTS OF BILL PULLING AWAY FROM OUR REGION AND TRACKING UP TOWARD SOUTHERN NEW ENGLAND, WE SIGNIFICANTLY LOWERED POPS ACROSS THE FORECAST AREA THROUGH THE REST OF THE MORNING, AS MOST LOCATIONS WILL EXPERIENCE DRY CONDITIONS AND GRADUAL CLEARING SKIES OVER THE NEXT SEVERAL HOURS. FOR THIS AFTERNOON, WITH A DESTABILIZING ATMOSPHERE AND AN APPROACHING SHORTWAVE AND COLD FRONT FROM THE WEST, WE INTRODUCE SOME CHANCE POPS, ESPECIALLY FOR OUR NORTHWEST ZONES, WITH BOTH THE HRRR AND RAP SUPPORTING THIS REGION FOR POSSIBLE CONVECTIVE DEVELOPMENT. HOURLY TEMPS AND DEWPOINTS WERE ALSO ADJUSTED USING THE LAV/LAMP GUIDANCE. OTHERWISE...HIGH TEMPS LOOK TO BE AROUND 90, AND DEW POINTS WILL BE CLOSE TO 70 WHICH WILL MAKE IT FEEL A BIT STICKY. THE ONLY SAVING GRACE WILL BE THAT THE WIND WILL BECOME MORE WLY BEHIND THE CFP AND IT WILL BE A BIT BREEZY. THE SUMMER SOLSTICE OCCURS AT 1238 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/... AFTER ANY EVE SHWRS/TSTMS AS MENTIONED ABOVE, WK HIGH PRES WILL BUILD IN FOR SUN NIGHT AND PRECIP WILL END AND HUMIDITY LEVELS WILL DROP AS THE WIND CONTINUES FROM THE W AND EVEN PSBLY NW BRINGS IN DRIER AIR. && .LONG TERM /MONDAY THROUGH SATURDAY/... DRAFT: **HOT TUESDAY, POSSIBLY NEAR RECORD** 500 MB: WARM HIGH PRESSURE COVERS THE SOUTHERN UNITED STATES WITH A PREDOMINANTLY WEST-NORTHWEST FLOW ALONG THE PERIPHERY OF THE RIDGE IN THE NORTHERN UNITED STATES TRENDING TO A TROUGH OVER THE WESTERN GREAT LAKES NEXT WEEKEND. CALENDAR DAY AVERAGES TUESDAY WILL BE 5 TO 10 DEGREES ABOVE NORMAL, AND THEN PROBABLY WITHIN 3 DEGREES OF NORMAL WEDNESDAY THROUGH SUNDAY. DAYTIME MAX`S FRIDAY MIGHT BE 10 DEGREES OR MORE BELOW NORMAL-A COOLISH DAY! FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 12Z/21 GFS/NAM MOS GUIDANCE MONDAY NIGHT-TUESDAY NIGHT, 12Z/21 MEX MOS WEDNESDAY AND WEDNESDAY NIGHT, THEN THE 1521Z/21 WPC GRIDDED ELEMENTS OF MAX/MIN TEMP, 12 HOUR POP, 6 HOUR DEWPOINT-SKY-WIND FROM THURSDAY THROUGH NEXT MONDAY. THE DAILIES... MONDAY...FOR THE MOST PART, MONDAY LOOKS VERY NICE. PLENTY OF SUNSHINE. PWAT ONLY 1 INCH! SFC DEWPOINTS ALMOST 10F LOWER THAN THE VALUES OF SUNDAY AFTERNOON. WEST WIND GUSTS GENERALLY UNDER 15 MPH. CONFIDENCE: ABOVE AVERAGE. MONDAY NIGHT...WAA MID AND HIGH CLOUD ARRIVES LATE. SMALL CHANCE AND NOT YET MENTIONED, OF A SHOWER GRAZING THE POCONOS AT DAWN TUESDAY. CONFIDENCE ON SCENARIO: ABOVE AVERAGE. TUESDAY...HOT AND HUMID! A COLD FRONT IS EXPECTED TO ARRIVE IN THE LATTER HALF OF THE DAY. AS SUCH, SHOULD SEE CONVECTIVE CHANCES AHEAD OF AND WITH THE FRONT. SREF PWAT 1.5 TO 1.75 INCHES DURING THE AFTERNOON/EVENING. MLCAPE OVER 2000J BY LATE IN THE DAY. 0-6KM BULK QUITE STRONG WITH 50 KT AT 500MB NEAR AND N I-78 AND TT LOWER 50S WITH SWI -4. LANCE POINTED OUT THE ELEVATED MIXED LAYER (EML) IN THE SOUNDING AND NICELY SEEN IN BOTH THE EC AND GFS PLAN VIEW BREAKING FREE FROM THE OHIO VALLEY MONDAY AND APPEARING ALONG AND SOUTH OF THE MASON DIXON LINE 18Z TUESDAY. THE EML OFFERS ADDITIONAL STRENGTH POTENTIAL IF CONVECTION ERUPTS. WE`RE ALSO NOTING HIGH FORECAST SHERB VALUES FOR OUR AREA TUESDAY (VALUES OVER 1). POPS LOOKED A LITTLE LOW BUT ITS POSSIBLE THAT THERE MIGHT NOT BE ENOUGH CONVERGENCE TO INITIATE CONVECTION. CONFIDENCE ON HEAT INCLUDING 95-96F AT PHL IS ABOVE AVG. CONFIDENCE ON CONVECTION: AVERAGE WITH MODELED PARAMETERS FOR SVR IMPRESSIVE. WEDNESDAY...PROBABLY DRY AND NICE AGAIN. CONFIDENCE: AVERAGE OR A BIT ABOVE. THURSDAY THROUGH SATURDAY...COMPLEX AND NOT GIVEN TO ADDING MUCH INFORMATION EXCEPT TO SAY THERE IS A CHANCE OF PERIODIC CONVECTION, ESPECIALLY NEXT SATURDAY. CONFIDENCE OVERALL IS AVERAGE. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CONTINUED IMPROVEMENT FROM MVFR CIGS TO VFR CIGS IS EXPECTED THROUGH LATE MORNING FOR THE TAF SITES. WEST-NORTHWEST WINDS IN THE 10 TO 15 KNOT RANGE WILL GUST AT TIMES TO BETWEEN 20 TO 25 KNOTS, BEFORE SUBSIDING THIS EVENING. LATER IN THE DAY, THERE COULD BE SCATTERED SHWRS OR EVEN A TSTM AS THE CDFNT ASSOCD WITH THE LOW AND AN UPR LVL DISTURBANCE PASSES BY. HOWEVER, AREAL COVERAGE IS ONCE AGAIN EXPECTED TO BE SMALL, SO NOT INCLUDING IN THE TAFS AT THIS TIME. OUTSIDE OF ANY SHRA/TSRA, VFR CONDS SHUD PREVAIL FOR THE BALANCE OF THE DAY AFTER THIS MORNING. OUTLOOK... MONDAY...VFR SCT AOA 5000 FT. NW GUST 20 POSSIBLY 25 KT EARLY THEN DIMINISHES LATE DAY. CONFIDENCE: ABOVE AVERAGE. MONDAY NIGHT...VFR LIGHT WIND. VFR CIGS DEVELOPING LATE AT NIGHT. CONFIDENCE: ABOVE AVERAGE. TUESDAY...VFR SCT-BKN AOA 5000 FT LOWERING TO BRIEF IFR CONDITIONS WITH SHOWERS AND STRONG GUSTY TSTORMS LATE IN THE DAY OR MORE LIKELY EVENING. GRADIENT SW WIND GUSTS 20-25 KT SHIFT NW AT NIGHT BUT GUSTS UNDER 20 KT. CONFIDENCE: ABOVE AVERAGE WEDNESDAY...VFR DAYTIME WITH POSSIBLE CIGS ARRIVING AT NIGHT. NW GUSTS UNDER 15 KT BECOMING LIGHT NE AT NIGHT. CONFIDENCE: AVERAGE THURSDAY...VFR CIGS DURING THE DAY WITH CHANCE OF A SHOWER OR TSTM. MVFR/IFR CONDS IN STRATUS-FOG POSSIBLE LATE AT NIGHT. CONFIDENCE: AVERAGE. && .MARINE... THE SCA WILL BE CONTINUED THRU 22/00Z. AFTER THAT CONFIDENCE IS MUCH LOWER SO IT WAS NOT EXTENDED ATTM. IF THERE NEEDS TO BE AN EXTENSION, IT WUD LIKELY BE FOR SEAS AS WIND SHUD BE BELOW CRITERIA. OTHERWISE, ONCE WE GET BEYOND THIS SCA, NO ADDITIONAL MARINE FLAGS ARE ANTICIPATED. OUTLOOK... MONDAY...SCA POSSIBLE IN THE MORNING FOR THE ATLC WATERS THEN NW WINDS SUBSIDE AFTERNOON/EVENING. CONFIDENCE: AVERAGE. TUESDAY...SCA SW WIND GUSTS POSSIBLE DURING THE AFTERNOON ALONG THE NEARSHORE WATERS. CONFIDENCE: AVERAGE. WEDNESDAY AND MOST OF THURSDAY...WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. CONFIDENCE: AVERAGE. && .RIP CURRENTS... 11 AM ASSESSMENT INCLUDING INFORMATION GATHERED FROM OUR 1015 AM CONFERENCE CALL WITH 4 BEACH PATROLS. THE FORMATION RISK WAS PROBABLY HIGHEST THIS MRNG. NOW THAT WINDS ARE WLY, WE`RE NO LONGER BUILDING THE WATER LEVEL IN THE SURF ZONE. ON THE OTHER HAND AS THE TIDE MOVES INTO THE LOWER HALF OF THE TIDE CYCLE AFTER 2 PM...WHATEVER RISK FOR THE FORMATION OF DANGEROUS RIP CURRENTS EXISTS, IT TENDS TO ELEVATE DUE TO SAND BAR EXPOSURE AND RESIDUAL WATER BUILD UP. LONG PERIOD SWELLS ARE AT A MINIMUM TODAY SO THE CONTRIBUTUION OF WATER BUILDUP BEHIND THE BARS SHOULD BE PRIMARILY ASSOCIATED WITH A GRADUALLY LOWERING SHORT PERIOD SOUTHERLY SWELL. WE HAD A COUPLE OF REPORTS FROM NORTH WILDWOOD AND ISLAND BEACH STATE PARK ABOUT CONCERN THAT THE RIP CURRENT FORMATION LATE THIS MORNING WAS BORDERING HIGH RISK. FOR NOW..DUE TO THE EXPECTED WESTERLY WIND IMPACT, WE`LL MAINTAIN A MODERATE RISK FOR THE FORMATION OF DANGEROUS RIP CURRENTS ALONG THE NJ COAST. MEDIA ARE RECOMMENDED TO ADVISE CAUTION FOR SWIMMERS GOING INTO THE WATERS THIS AFTERNOON AND PLEASE SWIM IN THE PRESENCE OF LIFEGUARDS. THERE IS MORE THAN THE USUAL RISK FOR THE FORMATION OF DANGEROUS RIP CURRENTS. && .CLIMATE... VULNERABLE TO THE MAX TEMP WITHIN 2F OF EQUALING THE RECORD MAX TEMPERATURES FOR TUESDAY JUNE 23 KACY 98-1988 KILG 100-1894 KPHL 97-1888 KABE 95-1965 KTTN 97-1894 KRDG 96-1908 KMPO 90-1908 KGED 100-1988 RAINFALL: THE PAST WEEK FROM THE 14TH THROUGH 20TH "NOT INCLUDING TODAYS SO FAR". A GRAPHIC AND LINK WITH MORE DETAIL WILL POST ON OUR SOCIAL MEDIA FB PAGE AND WILL BE TWEETED. KMPO 2.07 7 CONSEC DAYS OF SOME RAIN KRDG 1.69 7 CONSEC DAYS OF SOME RAIN KABE 1.91 6 OF 7 DAYS IT RAINED KTTN 0.84 6 OF 7 DAYS IT RAINED KPHL 1.49 7 CONSEC DAYS OF RAIN KILG 2.70 7 CONSEC DAYS OF RAIN KACY 1.18 6 OF 7 DAYS IT RAINED KGED 1.06 6 OF 7 DAYS IT RAINED WHEN WE ADD TODAYS RAINFALL THROUGH 9 AM... IT WILL HAVE RAINED 8 CONSEC DAYS AT KMPO/KRDG/KPHL AND KILG AND 7 OF 8 ELSEWHERE. KILG: THE 9.18 INCHES FOR THE MONTH AS OF 845 AM THIS MORNING IS STILL 4TH WETTEST JUNE ON RECORD. 2013 13.66 2003 9.90 2006 9.40 2015 9.18 POR FOR THIS STATION IN JUNE IS BACK TO 1896. INTERESTINGLY, IN THE NEARLY 120 YEAR PERIOD OF RECORD, THE TOP 4 MONTHLY JUNE RAINFALL TOTALS ALL OCCURRED IN THE LAST 13 YEARS. TEMPS THROUGH THE 20TH ARE AVERAGING 1.3 TO 2.4 DEGREES ABOVE NORMAL THROUGHOUT THE CWA. && .EQUIPMENT... RTPPHI IS MISSING A FAIR AMOUNT OF DATA THIS MORNING DUE TO THE FAA MAINTENANCE PERIOD FROM 315Z-815Z OVERNIGHT. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ450>455. && $$ SYNOPSIS...DRAG/JOHNSON NEAR TERM...KLINE/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...DRAG AVIATION...DRAG/KLINE/NIERENBERG MARINE...DRAG/NIERENBERG RIP CURRENTS...DRAG 1123 CLIMATE... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1033 AM EDT SUN JUN 21 2015 .SYNOPSIS... THE REMNANTS OF TROPICAL DEPRESSION BILL WILL CONTINUE TO LIFT NORTHEAST AWAY FROM THE REGION TODAY. A WEAK COLD FRONT FOLLOWS TONIGHT WITH A STRONGER COLD FRONT EXPECTED TO SWING THROUGH OUR REGION LATE TUESDAY. A COMPLEX FRONTAL SYSTEM WILL AFFECT THE MID ATLANTIC STATES LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH THE REMNANTS OF BILL PULLING AWAY FROM OUR REGION AND TRACKING UP TOWARD SOUTHERN NEW ENGLAND, WE SIGNIFICANTLY LOWERED POPS ACROSS THE FORECAST AREA THROUGH THE REST OF THE MORNING, AS MOST LOCATIONS WILL EXPERIENCE DRY CONDITIONS AND GRADUAL CLEARING SKIES OVER THE NEXT SEVERAL HOURS. FOR THIS AFTERNOON, WITH A DESTABILIZING ATMOSPHERE AND AN APPROACHING SHORTWAVE AND COLD FRONT FROM THE WEST, WE INTRODUCE SOME CHANCE POPS, ESPECIALLY FOR OUR NORTHWEST ZONES, WITH BOTH THE HRRR AND RAP SUPPORTING THIS REGION FOR POSSIBLE CONVECTIVE DEVELOPMENT. HOURLY TEMPS AND DEWPOINTS WERE ALSO ADJUSTED USING THE LAV/LAMP GUIDANCE. OTHERWISE...HIGH TEMPS LOOK TO BE AROUND 90, AND DEW POINTS WILL BE CLOSE TO 70 WHICH WILL MAKE IT FEEL A BIT STICKY. THE ONLY SAVING GRACE WILL BE THAT THE WIND WILL BECOME MORE WLY BEHIND THE CFP AND IT WILL BE A BIT BREEZY. THE SUMMER SOLSTICE OCCURS AT 1238 PM. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM MONDAY/... AFTER ANY EVE SHWRS/TSTMS AS MENTIONED ABOVE, WK HIGH PRES WILL BUILD IN FOR SUN NIGHT AND PRECIP WILL END AND HUMIDITY LEVELS WILL DROP AS THE WIND CONTINUES FROM THE W AND EVEN PSBLY NW BRINGS IN DRIER AIR. && .LONG TERM /MONDAY THROUGH SATURDAY/... FEW CHANGES MADE TO THE LONG TERM OVERNIGHT TO FOCUS ON CURRENT EVENT. PREVIOUS LONG TERM DISCUSSION: **RATHER HOT TUESDAY, POSSIBLY NEAR RECORD** 500 MB: WARM HIGH PRESSURE COVERS THE SOUTHERN UNITED STATES WITH A PREDOMINANTLY ZONAL FLOW IN THE NORTHERN UNITED STATES TRENDING TO A TROUGH OVER THE MIDWEST NEXT WEEKEND. JUNE THROUGH THE FIRST 19 DAYS HAS AVERAGED 1 TO 2.5 DEGREES ABOVE NORMAL. CALENDAR DAY AVERAGES MONDAY AND TUESDAY WILL AVERAGE 5 TO 10 DEGREES ABOVE NORMAL, NEAR 5 ABOVE NORMAL WEDNESDAY AND THEN PROBABLY NEAR NORMAL NEXT THURSDAY-FRIDAY-SATURDAY. FORECAST BASIS: UNLESS OTHERWISE NOTED, A 50 50 BLEND 12Z/20 GFS/NAM MOS GUIDANCE SUNDAY NIGHT-MONDAY NIGHT, 12Z/20 MEX MOS TUESDAY AND TUESDAY NIGHT, THEN THE 1521Z/20 WPC GRIDDED ELEMENTS OF MAX/MIN TEMP, 12 HOUR POP, 6 HOUR DEWPOINT-SKY-WIND FROM WEDNESDAY THROUGH NEXT SUNDAY. THE DAILIES... MONDAY...FOR THE MOST PART, MONDAY LOOKS VERY NICE. PLENTY OF SUNSHINE. PWAT ONLY 1 INCH! SFC DEWPOINTS ALMOST 10F LOWER THAN THE VALUES OF SUNDAY AFTERNOON. WEST WIND GUSTS GENERALLY UNDER 15 MPH. CONFIDENCE: ABOVE AVERAGE. MONDAY NIGHT...WAA MID AND HIGH CLOUD ARRIVES LATE. SMALL CHANCE AND NOT YET MENTIONED, OF A SHOWER GRAZING THE POCONOS AT DAWN TUESDAY. CONFIDENCE ON SCENARIO: ABOVE AVERAGE. TUESDAY...HOT AND HUMID! A COLD FRONT IS EXPECTED TO ARRIVE IN THE LATTER HALF OF THE DAY. AS SUCH, SHOULD SEE CONVECTIVE CHANCES AHEAD OF AND WITH THE FRONT. SREF PWAT 1.5 TO 1.75 INCHES DURING THE AFTERNOON/EVENING. MLCAPE OVER 2000J BY LATE IN THE DAY. 0-6KM BULK QUITE STRONG WITH 50 KT AT 500MB NEAR AND N I-78 AND TT LOWER 50S WITH SWI -4. LANCE POINTED OUT THE ELEVATED MIXED LAYER (EML) IN THE SOUNDING AND NICELY SEEN IN BOTH THE EC AND GFS PLAN VIEW BREAKING FREE FROM THE OHIO VALLEY MONDAY AND APPEARING ALONG AND SOUTH OF THE MASON DIXON LINE 18Z TUESDAY. THE EML OFFERS ADDITIONAL STRENGTH POTENTIAL IF CONVECTION ERUPTS. WE`RE ALSO NOTING HIGH FORECAST SHERB VALUES FOR OUR AREA TUESDAY (VALUES OVER 1). POPS LOOKED A LITTLE LOW BUT ITS POSSIBLE THAT THERE MIGHT NOT BE ENOUGH CONVERGENCE TO INITIATE CONVECTION. CONFIDENCE ON HEAT INCLUDING 95-96F AT PHL IS ABOVE AVG. CONFIDENCE ON CONVECTION: AVERAGE WITH MODELED PARAMETERS FOR SVR IMPRESSIVE. WEDNESDAY...PROBABLY DRY AND NICE AGAIN. CONFIDENCE: AVERAGE OR A BIT ABOVE. THURSDAY THROUGH SATURDAY...COMPLEX AND NOT GIVEN TO ADDING MUCH INFORMATION EXCEPT TO SAY THERE IS A CHANCE OF PERIODIC CONVECTION, ESPECIALLY NEXT SATURDAY. CONFIDENCE OVERALL IS AVERAGE. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CONTINUED IMPROVEMENT FROM MVFR CIGS TO VFR CIGS IS EXPECTED THROUGH LATE MORNING FOR THE TAF SITES. WEST-NORTHWEST WINDS IN THE 10 TO 15 KNOT RANGE WILL GUST AT TIMES TO BETWEEN 20 TO 25 KNOTS, BEFORE SUBSIDING THIS EVENING. LATER IN THE DAY, THERE COULD BE SCATTERED SHWRS OR EVEN A TSTM AS THE CDFNT ASSOCD WITH THE LOW AND AN UPR LVL DISTURBANCE PASSES BY. HOWEVER, AREAL COVERAGE IS ONCE AGAIN EXPECTED TO BE SMALL, SO NOT INCLUDING IN THE TAFS AT THIS TIME. OUTSIDE OF ANY SHRA/TSRA, VFR CONDS SHUD PREVAIL FOR THE BALANCE OF THE DAY AFTER THIS MORNING. OUTLOOK... MONDAY...VFR SCT AOA 5000 FT. NW GUST 20 POSSIBLY 25 KT EARLY THEN DIMINISHES LATE DAY. CONFIDENCE: ABOVE AVERAGE. MONDAY NIGHT...VFR LIGHT WIND. VFR CIGS DEVELOPING LATE AT NIGHT. CONFIDENCE: ABOVE AVERAGE. TUESDAY...VFR SCT-BKN AOA 5000 FT LOWERING TO BRIEF IFR CONDITIONS WITH SHOWERS AND STRONG GUSTY TSTORMS LATE IN THE DAY OR MORE LIKELY EVENING. GRADIENT SW WIND GUSTS 20-25 KT SHIFT NW AT NIGHT BUT GUSTS UNDER 20 KT. CONFIDENCE: ABOVE AVERAGE WEDNESDAY...VFR DAYTIME WITH POSSIBLE CIGS ARRIVING AT NIGHT. NW GUSTS UNDER 15 KT BECOMING LIGHT NE AT NIGHT. CONFIDENCE: AVERAGE THURSDAY...VFR CIGS DURING THE DAY WITH CHANCE OF A SHOWER OR TSTM. MVFR/IFR CONDS IN STRATUS-FOG POSSIBLE LATE AT NIGHT. CONFIDENCE: AVERAGE. && .MARINE... THE SCA WILL BE CONTINUED THRU 22/00Z. AFTER THAT CONFIDENCE IS MUCH LOWER SO IT WAS NOT EXTENDED ATTM. IF THERE NEEDS TO BE AN EXTENSION, IT WUD LIKELY BE FOR SEAS AS WIND SHUD BE BELOW CRITERIA. OTHERWISE, ONCE WE GET BEYOND THIS SCA, NO ADDITIONAL MARINE FLAGS ARE ANTICIPATED. OUTLOOK... MONDAY...SCA POSSIBLE IN THE MORNING FOR THE ATLC WATERS THEN NW WINDS SUBSIDE AFTERNOON/EVENING. CONFIDENCE: AVERAGE. TUESDAY...SCA SW WIND GUSTS POSSIBLE DURING THE AFTERNOON ALONG THE NEARSHORE WATERS. CONFIDENCE: AVERAGE. WEDNESDAY AND MOST OF THURSDAY...WINDS AND SEAS SHOULD STAY BELOW SCA CRITERIA. CONFIDENCE: AVERAGE. && .RIP CURRENTS... WITH A GUSTY WIND AND ELEVATED SEAS, GUID INDICATES THAT RIP CURRENT RISK WILL BE MODERATE TODAY. HOWEVER, ITS POSSIBLE THAT THE RISK MAY BE HIGHEST IN THE MRNG, BECAUSE AS THE WIND BECOMES MORE WLY AND NWLY AND THE WAVES ARE PUSHED AWAY FROM THE SHORE, THE RISK CUD LOWER AS THE SEAS DO. CONDS WILL BE FURTHER ASSESSED LATER TODAY. && .CLIMATE... VULNERABLE TO THE MAX TEMP WITHIN 2F OF EQUALING THE RECORD MAX TEMPERATURES FOR TUESDAY JUNE 23 KACY 98-1988 KILG 100-1894 KPHL 97-1888 KABE 95-1965 KTTN 97-1894 KRDG 96-1908 KMPO 90-1908 KGED 100-1988 RAINFALL: THE PAST WEEK FROM THE 14TH THROUGH 20TH "NOT INCLUDING TODAYS SO FAR". A GRAPHIC AND LINK WITH MORE DETAIL WILL POST ON OUR SOCIAL MEDIA FB PAGE AND WILL BE TWEETED. KMPO 2.07 7 CONSEC DAYS OF SOME RAIN KRDG 1.69 7 CONSEC DAYS OF SOME RAIN KABE 1.91 6 OF 7 DAYS IT RAINED KTTN 0.84 6 OF 7 DAYS IT RAINED KPHL 1.49 7 CONSEC DAYS OF RAIN KILG 2.70 7 CONSEC DAYS OF RAIN KACY 1.18 6 OF 7 DAYS IT RAINED KGED 1.06 6 OF 7 DAYS IT RAINED WHEN WE ADD TODAYS RAINFALL THROUGH 9 AM... IT WILL HAVE RAINED 8 CONSEC DAYS AT KMPO/KRDG/KPHL AND KILG AND 7 OF 8 ELSEWHERE. KILG: THE 9.18 INCHES FOR THE MONTH AS OF 845 AM THIS MORNING IS STILL 4TH WETTEST JUNE ON RECORD. 2013 13.66 2003 9.90 2006 9.40 2015 9.18 POR FOR THIS STATION IN JUNE IS BACK TO 1896. INTERESTINGLY, IN THE NEARLY 120 YEAR PERIOD OF RECORD, THE TOP 4 MONTHLY JUNE RAINFALL TOTALS ALL OCCURRED IN THE LAST 13 YEARS. TEMPS THROUGH THE 20TH ARE AVERAGING 1.3 TO 2.4 DEGREES ABOVE NORMAL THROUGHOUT THE CWA. && .EQUIPMENT... RTPPHI IS MISSING A FAIR AMOUNT OF DATA THIS MORNING DUE TO THE FAA MAINTENANCE PERIOD FROM 315Z-815Z OVERNIGHT. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR ANZ450>455. && $$ SYNOPSIS...DRAG/JOHNSON NEAR TERM...KLINE/NIERENBERG SHORT TERM...NIERENBERG LONG TERM...DRAG AVIATION...DRAG/KLINE/NIERENBERG MARINE...DRAG/NIERENBERG RIP CURRENTS... CLIMATE...DRAG EQUIPMENT...DRAG
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
325 AM CDT SUN JUN 21 2015 .SHORT TERM... 329 PM CDT THROUGH TONIGHT... STILL LINGERING UNCERTAINTY REGARDING THE POTENTIAL FOR STRONG TO SEVERE STORMS THIS EVENING...WITH AN OVERALL TREND TOWARD A LOWER THREAT FOR THE THE NORTHEAST 1/2 TO 2/3 OF THE CWA. AS NOTED EARLIER...CLOUD COVER HAS OVERALL LIMITED DESTABILIZATION PROCESS EVEN IN PRESENCE OF GRADUALLY MOISTENING DEWPOINTS. ALSO A VERY STOUT WARM NOSE AT BASE OF EML ADVECTING WESTWARD CENTERED FROM 750-850 MB NOTED ON 18Z DVN SOUNDING WILL RESULT IN CAPPING/CINH AS DESTABILIZATION OCCURS LATE THIS AFTERNOON. ITS APPEARS THAT LINGERING CLUSTER OF THUNDERSTORMS OVER NORTHEAST IA AND NORTHWEST IL ON NOSE OF SPEED MAX SEEN ON W/V IMAGERY COULD BE MAIN FOCUS FOR WHAT OCCURS THIS EVENING...ONCE STRONGER FORCING ARRIVES AND WEAKENS THE CAP. IT STILL LOOKS THAT STRONGEST INSTABILITY AXIS WITH MLCAPE UP TO 1K TO 2K J/KG WILL RESIDE NEAR OR JUST WEST OF THE FAR WEST AND SOUTHWEST CWA. MORE ROBUST CONVECTION LIKELY WILL RIDE THIS NORTH- NORTHWEST TO SOUTH- SOUTHEAST AXIS THIS EVENING. THEREFORE...IN PRESENCE OF DEEP LAYER SHEAR OF 40-50 KT...HIGHEST POTENTIAL FOR SEVERE WEATHER IS FAVORED TO BE WEST OF DIXON TO OTTAWA TO PAXTON LINE...FAIRLY SIMILAR TO RECENT RUNS OF HRRR. UPSCALE GROWTH INTO MCS MAY BE OCCURRING BY TIME STORMS ARRIVE...SO PRIMARY THREATS FROM ANY SEVERE STORMS LOOK TO BE DAMAGING WIND GUSTS AND LARGE HAIL. FOR REST OF AREA...IT APPEARS BAND OF SHOWERS AND EMBEDDED STORMS WILL STILL PRESS SOUTHEAST AHEAD OF COLD FRONT AS DEPICTED ON RECENT HRRR RUNS...BUT WITH MUCH LOWER CHANCE FOR STRONG TO SEVERE THUNDERSTORMS. CLOUD TO GROUND LIGHTNING POTENTIAL MAY BE LIMITED BUT ALSO NON-ZERO FOR NORTHEAST ILLINOIS AND NORTHWEST INDIANA...SOMETHING TO KEEP IN MIND FOR OUTDOOR ACTIVITIES THIS EVENING. COULD END UP BEING MORE OF A SHOWER/EMBEDDED THUNDER SCENARIO. FINALLY...ANY ORGANIZED THUNDERSTORMS COULD PRODUCE HEAVY DOWNPOURS WITH HIGH PWAT IN 1.7 TO 1.8 INCH RANGE SAGGING SOUTHWARD AHEAD OF THE FRONT. THUS GIVEN RECENT HEAVY RAINS...WILL ALSO NEED TO MONITOR FOR FLOOD POTENTIAL THIS EVENING EVEN IN FASTER STORM MOTIONS. OVERNIGHT LOWS WILL BE IN THE UPPER 60S TO LOWER 70S...WITH 60S DEWPOINTS YIELDING MUGGY CONDITIONS. RC && .LONG TERM... 329 PM CDT SUNDAY THROUGH SATURDAY... MAIN FORECAST CONCERNS/CHALLENGES FOR THE PERIOD REMAIN WITH AN ACTIVE WEATHER PATTERN WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS CONTINUING NEXT WEEK. THE PERIOD WILL BEGIN WITH FRONTAL BOUNDARY STILL LIKELY LINGERING ACROSS THE SOUTHERN THIRD OF THE CWA...WHERE UPPER 60S DEWPOINTS WILL STILL LIKELY RESIDE. WHILE CONVECTION FROM THE OVERNIGHT WILL HAVE LIKELY EXITED THE AREA BY THE MORNING...THERE APPEARS TO BE A CHANCE FOR FURTHER DEVELOPMENT ACROSS EAST CENTRAL ILLINOIS AND PORTIONS OF NORTHWEST INDIANA MAINLY SOUTH OF PONTIAC ILLINOIS TO MOROCCO INDIANA LINE. FORECAST SOUNDINGS IN THESE LOCATIONS ARE INDICATING INCREASING INSTABILITY WITH LITTLE TO NO CIN DURING THE MORNING AND ALTHOUGH THE CHANCE FOR ADDITIONAL DEVELOPMENT IS LOW...THERE DOES APPEAR TO BE A SMALL WINDOW BEFORE THE AXIS OF BEST DEVELOPMENT ALONG THIS BOUNDARY PUSHES SOUTH OF THE CWA BY MIDDAY. THE AFTERNOON WILL LIKELY BE DRY WITH CLEARING SKIES...AND WITH TEMPERATURES INCREASING INTO THE 80S. WINDS NEAR THE LAKE WILL BEGIN OUT OF THE NORTHWEST TO NORTH AND WITH A SHIFT TO THE NORTHEAST/EAST LIKELY BY MIDDAY...LIMITING TEMPS TO THE 70S. CONDITIONS APPEAR TO BE QUIET SUNDAY EVENING AND THROUGH MUCH OF SUNDAY NIGHT. HOWEVER...ATTENTION TURNS BACK WEST TOWARDS INCREASING MID LEVEL ENERGY AND A STRENGTHENING LLJ. THESE FEATURES WILL ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT WELL WEST OF THE CWA ACROSS IOWA FOR MOST OF THE NIGHT. SOME OF THIS DEVELOPMENT COULD POSSIBLY REACH THE FAR WESTERN CWA LATE SUNDAY NIGHT INTO MONDAY MORNING AND HAVE MAINTAINED SLIGHT CHANCE WORDING DURING THIS TIME. THE BETTER CHANCES WILL COME MONDAY MORNING WHEN SCATTERED THUNDERSTORM DEVELOPMENT APPEARS POSSIBLE. VEERING LLJ...APPROACHING MID LEVEL SUPPORT...AND GOOD MOIST/TEMP ADVECTION SHOULD PROVIDE AMPLE SUPPORT FOR AT LEAST SCATTERED THUNDERSTORM DEVELOPMENT. WITH THIS DECENT FORCING IN PLACE AND WHILE MODERATE/STRONG INSTABILITY ALOFT QUICKLY LIFTS NORTH ACROSS THE CWA...COULD ALLOW FOR SOME OF THESE STORMS TO BE STRONG TO SEVERE. THE LIKELY HAZARD WOULD BE FOR LARGE HAIL...BEFORE THIS DEVELOPMENT LIFTS NORTH OF THE CWA BY MIDDAY. GUIDANCE DOES VARY TO HOW MONDAY AFTERNOON WILL EVOLVE WITH REGARD TO ADDITIONAL THUNDERSTORM DEVELOPMENT...BUT IT WOULD APPEAR THAT THERE WILL BE A DRY WINDOW DURING THIS TIME. PERSISTING WARM/MOIST PUSH RIDING ALONG STRONG SOUTH TO SOUTHWEST WINDS WILL BE OBSERVED MONDAY AND IF THE CLOUDS CAN DEPART...TEMPS IN THE MID TO UPPER 80S WILL BE LIKELY. ANOTHER DECENT CHANCE FOR THUNDERSTORM ARRIVING MONDAY NIGHT WITH THE POTENTIAL FOR SOME OF THEM TO BE STRONG TO SEVERE. HAVE NOT INCREASE POPS DURING THIS TIME TOO MUCH OWING TO SOME UNCERTAINTY WITH COVERAGE AND EXACT TIMING. HOWEVER...WITH A SURFACE TROUGH AND FRONT PUSHING THROUGH THE AREA...DEVELOPMENT DEFINITELY APPEARS POSSIBLE. THIS FRONT SHOULD PUSH THROUGH THE CWA BY TUESDAY BUT THERE IS A POSSIBILITY THAT IT COULD LINGER ACROSS THE SOUTHERN CWA DURING THIS TIME. IF IT DOES...THERE WILL BE ADDITIONAL CHANCES OVER THE SOUTHERN CWA. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * MVFR CIGS AND MVFR VSBYS OVERNIGHT INTO SUNDAY MORNING. * WINDS BECOMING GUSTY FROM THE NORTHWEST BY LATE MORNING. * POSSIBLE LAKE BREEZE/NORTHEAST WIND SHIFT LATE SUNDAY AFTERNOON/ EARLY EVENING. ED F //DISCUSSION...UPDATED 06Z... ISOLATED SHOWERS OVER NE ILLINOIS IN THE WAKE OF THE LARGE COMPLEX OF RAIN AND STORMS HAVING EXITED TO THE SOUTH EARLIER TONIGHT TO ALSO SLIDE SE/DISSIPATE NEXT COUPLE OF HOURS. MEANWHILE MVFR CIGS WILL SPREAD OUT ACROSS THE AREA GIVEN THE LACK OF ANY STRONG DRYING WITH THE WEAK COLD FRONT POISED TO DROP SOUTH ACROSS THE AREA THE REST OF TONIGHT. ALONG WITH RESIDUAL LOW LEVEL MOISTURE... WET GROUND AND LIGHT WINDS EXPECT VSBYS TO ALSO LOWER IN LIGHT FOG OVERNIGHT HOWEVER LOW CLOUDS WILL PREVENT VSBYS FROM DROPPING BELOW 3-4 SM AT ORD AND MDW. NO RAIN EXPECTED SUNDAY WITH NORTHWEST WINDS INCREASING BEHIND THE COLD FRONT BY LATE MORNING AND BECOMING GUSTY. SOME QUESTION AS TO WHETHER A LAKE BREEZE BOUNDARY MAY DEVELOP AND REACH THE TERMINALS BY LATE IN THE DAY WITH FAIRLY STOUT NORTHWEST TO WEST GRADIENT WIND DIMINISHING POSSIBLY ENOUGH BY LATE AFTERNOON. ED F //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM TO HIGH FOR MVFR CIGS AND MVFR VSBYS OVERNIGHT INTO SUNDAY MORNING. * MEDIUM FOR WIND TRENDS TONIGHT AND SUNDAY. * HIGH FOR OTHER FORECAST ELEMENTS. ED F //OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z... * MONDAY...CHANCE OF SHRA/TSRA. STRONG/GUSTY SOUTHWEST WINDS. * TUESDAY...DRY/VFR. NORTHEAST WINDS. * WEDNESDAY AND THURSDAY...CHANCE OF SHRA/TSRA. EASTERLY WINDS. * FRIDAY...SLIGHT CHANCE OF SHRA/TSRA. NORTHEAST WINDS. && .MARINE... 325 AM CDT LOW PRESSURE AND ITS ASSOCIATED COLD FRONT EXITING THE WESTERN GREAT LAKES THIS MORNING WILL TURN WINDS NORTHWEST ACROSS LAKE MICHIGAN. WEAK HIGH PRESSURE BUILDING EAST QUICKLY BEHIND THE COLD FRONT WILL CAUSE WINDS TO SLACKEN BY EVENING FOLLOWED BY A PERIOD OF LIGHT AND VARIABLE WINDS TONIGHT BEFORE RETURN SOUTHERLY FLOW SETS UP MONDAY. SOUTH WINDS WILL INTENSIFY RAPIDLY MONDAY AHEAD OF FAIRLY STRONG LOW PRESSURE FOR THIS TIME OF YEAR. AS THE LOW MOVES TO THE U P OF MICHIGAN BY MONDAY EVENING AND THEN QUICKLY INTO ONTARIO MONDAY NIGHT... IT WILL DRIVE A COLD FRONT SOUTHEAST ACROSS THE LENGTH OF THE LAKE BY DAYBREAK TUESDAY. WINDS AND WAVES WILL THEN EASE TUESDAY AS THE GRADIENT RELAXES AS THE LOW AND FRONT PULL AWAY AND ANOTHER AREA OF HIGH PRESSURE BUILDS EAST INTO THE AREA TUESDAY NIGHT INTO WEDNESDAY. YET ANOTHER AREA OF LOW PRESSURE WILL MOVE EAST TO SOUTHERN LAKE MICHIGAN THURSDAY MORNING. ED F && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
109 AM CDT SUN JUN 21 2015 .SHORT TERM... 329 PM CDT THROUGH TONIGHT... STILL LINGERING UNCERTAINTY REGARDING THE POTENTIAL FOR STRONG TO SEVERE STORMS THIS EVENING...WITH AN OVERALL TREND TOWARD A LOWER THREAT FOR THE THE NORTHEAST 1/2 TO 2/3 OF THE CWA. AS NOTED EARLIER...CLOUD COVER HAS OVERALL LIMITED DESTABILIZATION PROCESS EVEN IN PRESENCE OF GRADUALLY MOISTENING DEWPOINTS. ALSO A VERY STOUT WARM NOSE AT BASE OF EML ADVECTING WESTWARD CENTERED FROM 750-850 MB NOTED ON 18Z DVN SOUNDING WILL RESULT IN CAPPING/CINH AS DESTABILIZATION OCCURS LATE THIS AFTERNOON. ITS APPEARS THAT LINGERING CLUSTER OF THUNDERSTORMS OVER NORTHEAST IA AND NORTHWEST IL ON NOSE OF SPEED MAX SEEN ON W/V IMAGERY COULD BE MAIN FOCUS FOR WHAT OCCURS THIS EVENING...ONCE STRONGER FORCING ARRIVES AND WEAKENS THE CAP. IT STILL LOOKS THAT STRONGEST INSTABILITY AXIS WITH MLCAPE UP TO 1K TO 2K J/KG WILL RESIDE NEAR OR JUST WEST OF THE FAR WEST AND SOUTHWEST CWA. MORE ROBUST CONVECTION LIKELY WILL RIDE THIS NORTH- NORTHWEST TO SOUTH- SOUTHEAST AXIS THIS EVENING. THEREFORE...IN PRESENCE OF DEEP LAYER SHEAR OF 40-50 KT...HIGHEST POTENTIAL FOR SEVERE WEATHER IS FAVORED TO BE WEST OF DIXON TO OTTAWA TO PAXTON LINE...FAIRLY SIMILAR TO RECENT RUNS OF HRRR. UPSCALE GROWTH INTO MCS MAY BE OCCURRING BY TIME STORMS ARRIVE...SO PRIMARY THREATS FROM ANY SEVERE STORMS LOOK TO BE DAMAGING WIND GUSTS AND LARGE HAIL. FOR REST OF AREA...IT APPEARS BAND OF SHOWERS AND EMBEDDED STORMS WILL STILL PRESS SOUTHEAST AHEAD OF COLD FRONT AS DEPICTED ON RECENT HRRR RUNS...BUT WITH MUCH LOWER CHANCE FOR STRONG TO SEVERE THUNDERSTORMS. CLOUD TO GROUND LIGHTNING POTENTIAL MAY BE LIMITED BUT ALSO NON-ZERO FOR NORTHEAST ILLINOIS AND NORTHWEST INDIANA...SOMETHING TO KEEP IN MIND FOR OUTDOOR ACTIVITIES THIS EVENING. COULD END UP BEING MORE OF A SHOWER/EMBEDDED THUNDER SCENARIO. FINALLY...ANY ORGANIZED THUNDERSTORMS COULD PRODUCE HEAVY DOWNPOURS WITH HIGH PWAT IN 1.7 TO 1.8 INCH RANGE SAGGING SOUTHWARD AHEAD OF THE FRONT. THUS GIVEN RECENT HEAVY RAINS...WILL ALSO NEED TO MONITOR FOR FLOOD POTENTIAL THIS EVENING EVEN IN FASTER STORM MOTIONS. OVERNIGHT LOWS WILL BE IN THE UPPER 60S TO LOWER 70S...WITH 60S DEWPOINTS YIELDING MUGGY CONDITIONS. RC && .LONG TERM... 329 PM CDT SUNDAY THROUGH SATURDAY... MAIN FORECAST CONCERNS/CHALLENGES FOR THE PERIOD REMAIN WITH AN ACTIVE WEATHER PATTERN WITH PERIODIC CHANCES FOR SHOWERS/THUNDERSTORMS CONTINUING NEXT WEEK. THE PERIOD WILL BEGIN WITH FRONTAL BOUNDARY STILL LIKELY LINGERING ACROSS THE SOUTHERN THIRD OF THE CWA...WHERE UPPER 60S DEWPOINTS WILL STILL LIKELY RESIDE. WHILE CONVECTION FROM THE OVERNIGHT WILL HAVE LIKELY EXITED THE AREA BY THE MORNING...THERE APPEARS TO BE A CHANCE FOR FURTHER DEVELOPMENT ACROSS EAST CENTRAL ILLINOIS AND PORTIONS OF NORTHWEST INDIANA MAINLY SOUTH OF PONTIAC ILLINOIS TO MOROCCO INDIANA LINE. FORECAST SOUNDINGS IN THESE LOCATIONS ARE INDICATING INCREASING INSTABILITY WITH LITTLE TO NO CIN DURING THE MORNING AND ALTHOUGH THE CHANCE FOR ADDITIONAL DEVELOPMENT IS LOW...THERE DOES APPEAR TO BE A SMALL WINDOW BEFORE THE AXIS OF BEST DEVELOPMENT ALONG THIS BOUNDARY PUSHES SOUTH OF THE CWA BY MIDDAY. THE AFTERNOON WILL LIKELY BE DRY WITH CLEARING SKIES...AND WITH TEMPERATURES INCREASING INTO THE 80S. WINDS NEAR THE LAKE WILL BEGIN OUT OF THE NORTHWEST TO NORTH AND WITH A SHIFT TO THE NORTHEAST/EAST LIKELY BY MIDDAY...LIMITING TEMPS TO THE 70S. CONDITIONS APPEAR TO BE QUIET SUNDAY EVENING AND THROUGH MUCH OF SUNDAY NIGHT. HOWEVER...ATTENTION TURNS BACK WEST TOWARDS INCREASING MID LEVEL ENERGY AND A STRENGTHENING LLJ. THESE FEATURES WILL ALLOW FOR SHOWER/THUNDERSTORM DEVELOPMENT WELL WEST OF THE CWA ACROSS IOWA FOR MOST OF THE NIGHT. SOME OF THIS DEVELOPMENT COULD POSSIBLY REACH THE FAR WESTERN CWA LATE SUNDAY NIGHT INTO MONDAY MORNING AND HAVE MAINTAINED SLIGHT CHANCE WORDING DURING THIS TIME. THE BETTER CHANCES WILL COME MONDAY MORNING WHEN SCATTERED THUNDERSTORM DEVELOPMENT APPEARS POSSIBLE. VEERING LLJ...APPROACHING MID LEVEL SUPPORT...AND GOOD MOIST/TEMP ADVECTION SHOULD PROVIDE AMPLE SUPPORT FOR AT LEAST SCATTERED THUNDERSTORM DEVELOPMENT. WITH THIS DECENT FORCING IN PLACE AND WHILE MODERATE/STRONG INSTABILITY ALOFT QUICKLY LIFTS NORTH ACROSS THE CWA...COULD ALLOW FOR SOME OF THESE STORMS TO BE STRONG TO SEVERE. THE LIKELY HAZARD WOULD BE FOR LARGE HAIL...BEFORE THIS DEVELOPMENT LIFTS NORTH OF THE CWA BY MIDDAY. GUIDANCE DOES VARY TO HOW MONDAY AFTERNOON WILL EVOLVE WITH REGARD TO ADDITIONAL THUNDERSTORM DEVELOPMENT...BUT IT WOULD APPEAR THAT THERE WILL BE A DRY WINDOW DURING THIS TIME. PERSISTING WARM/MOIST PUSH RIDING ALONG STRONG SOUTH TO SOUTHWEST WINDS WILL BE OBSERVED MONDAY AND IF THE CLOUDS CAN DEPART...TEMPS IN THE MID TO UPPER 80S WILL BE LIKELY. ANOTHER DECENT CHANCE FOR THUNDERSTORM ARRIVING MONDAY NIGHT WITH THE POTENTIAL FOR SOME OF THEM TO BE STRONG TO SEVERE. HAVE NOT INCREASE POPS DURING THIS TIME TOO MUCH OWING TO SOME UNCERTAINTY WITH COVERAGE AND EXACT TIMING. HOWEVER...WITH A SURFACE TROUGH AND FRONT PUSHING THROUGH THE AREA...DEVELOPMENT DEFINITELY APPEARS POSSIBLE. THIS FRONT SHOULD PUSH THROUGH THE CWA BY TUESDAY BUT THERE IS A POSSIBILITY THAT IT COULD LINGER ACROSS THE SOUTHERN CWA DURING THIS TIME. IF IT DOES...THERE WILL BE ADDITIONAL CHANCES OVER THE SOUTHERN CWA. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * MVFR CIGS AND MVFR VSBYS OVERNIGHT INTO SUNDAY MORNING. * WINDS BECOMING GUSTY FROM THE NORTHWEST BY LATE MORNING. * POSSIBLE LAKE BREEZE/NORTHEAST WIND SHIFT LATE SUNDAY AFTERNOON/ EARLY EVENING. ED F //DISCUSSION...UPDATED 06Z... ISOLATED SHOWERS OVER NE ILLINOIS IN THE WAKE OF THE LARGE COMPLEX OF RAIN AND STORMS HAVING EXITED TO THE SOUTH EARLIER TONIGHT TO ALSO SLIDE SE/DISSIPATE NEXT COUPLE OF HOURS. MEANWHILE MVFR CIGS WILL SPREAD OUT ACROSS THE AREA GIVEN THE LACK OF ANY STRONG DRYING WITH THE WEAK COLD FRONT POISED TO DROP SOUTH ACROSS THE AREA THE REST OF TONIGHT. ALONG WITH RESIDUAL LOW LEVEL MOISTURE... WET GROUND AND LIGHT WINDS EXPECT VSBYS TO ALSO LOWER IN LIGHT FOG OVERNIGHT HOWEVER LOW CLOUDS WILL PREVENT VSBYS FROM DROPPING BELOW 3-4 SM AT ORD AND MDW. NO RAIN EXPECTED SUNDAY WITH NORTHWEST WINDS INCREASING BEHIND THE COLD FRONT BY LATE MORNING AND BECOMING GUSTY. SOME QUESTION AS TO WHETHER A LAKE BREEZE BOUNDARY MAY DEVELOP AND REACH THE TERMINALS BY LATE IN THE DAY WITH FAIRLY STOUT NORTHWEST TO WEST GRADIENT WIND DIMINISHING POSSIBLY ENOUGH BY LATE AFTERNOON. ED F //ORD AND MDW CONFIDENCE...UPDATED 06Z... * MEDIUM TO HIGH FOR MVFR CIGS AND MVFR VSBYS OVERNIGHT INTO SUNDAY MORNING. * MEDIUM FOR WIND TRENDS TONIGHT AND SUNDAY. * HIGH FOR OTHER FORECAST ELEMENTS. ED F //OUTLOOK FOR ORD/MDW FOR 12Z MONDAY-12Z SATURDAY...UPDATED 00Z... * MONDAY...CHANCE OF SHRA/TSRA. STRONG/GUSTY SOUTHWEST WINDS. * TUESDAY...DRY/VFR. NORTHEAST WINDS. * WEDNESDAY AND THURSDAY...CHANCE OF SHRA/TSRA. EASTERLY WINDS. * FRIDAY...SLIGHT CHANCE OF SHRA/TSRA. NORTHEAST WINDS. && .MARINE... 408 PM CDT THERE WAS A BRIEF PERIOD OF STRONGER WINDS EARLIER THIS AFTERNOON OVER THE SOUTHERN HALF OF THE LAKE...POSSIBLY UP TO 33 KT FOR A TIME. HOWEVER...WINDS HAVE SINCE DIMINISHED BACK TO THE 10 TO 15 KT RANGE IN THE NEAR TERM. THESE SPEEDS WITH GENERALLY SOUTHERLY FLOW WILL CONTINUE THIS EVENING AND INTO A PORTION OF THE OVERNIGHT...BEFORE A TROUGH AND FRONTAL BOUNDARY MOVE ACROSS THE REGION. THIS WILL ALLOW FOR A WIND SHIFT TO THE NORTHWEST AND ALTHOUGH THERE COULD BE A SMALL WINDOW OF 10 TO 20 KT WINDS WITH THIS WIND SHIFT...THE MORE PREVAILING SPEEDS WILL BE IN THE 10 TO 15 KT RANGE. NORTHERLY FLOW WILL REMAIN SUNDAY MORNING BUT DIMINISH AND THEN LIKELY BECOME MORE LIGHT AND VARIABLE THROUGH THE REMAINDER OF THE DAY. EXPECT WINDS TO SHIFT BACK MORE SOUTHERLY SUNDAY NIGHT INTO MONDAY...AND THEN INCREASE DURING THIS TIME. THIS INCREASE WILL ESPECIALLY OCCUR MONDAY AFTERNOON INTO THE EVENING...WHEN SOUTHERLY WINDS UP TO 30 KT ARE APPEARING LIKELY. THIS WILL PERSIST UNTIL ANOTHER SYSTEM MOVES THROUGH MONDAY NIGHT...WITH WINDS THEN EXPECTED TO TURN TO THE NORTHWEST WHILE DIMINISHING. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...NONE. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSCHICAGO WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
AREA FORECAST DISCUSSION
NWS LINCOLN IL
1241 AM CDT SUN JUN 21 2015 .UPDATE... ISSUED AT 857 PM CDT SAT JUN 20 2015 A LINE OF STRONG TO SEVERE THUNDERSTORMS IS MOVING INTO WEST CENTRAL IL FROM THE NORTHWEST AHEAD OF A COLD FRONT MOVING SOUTHEASTWARD INTO THE AREA. SPC MESOANALYSIS SHOWING AROUND 4000 J/KG MLCAPE VALUES ALONG/SOUTH OF THE LINE WITH 30-50 KTS 0-6KM BULK SHEAR ACROSS NORTHERN HALF OF IL. AS A RESULT...ORGANIZED SEVERE CONVECTION SHOULD CONTINUE FOR MUCH OF THE EVENING THROUGH WEST CENTRAL IL AND A TORNADO WATCH REMAINS IN EFFECT UNTIL 11 PM. SEVERE WEATHER THREATS IN THIS AREA INCLUDE DAMAGING WIND GUSTS TO 60 MPH OR GREATER...LARGE HAIL...AND THE THREAT FOR AN ISOLATED TORNADO OR TWO. THUNDERSTORM ACTIVITY SHOULD SPREAD EAST AND SOUTH THROUGH CENTRAL/SE IL OVERNIGHT WITH SEVERE THUNDERSTORM THREAT SLOWLY DIMINISHING AND LARGELY SINKING SOUTHEASTWARD TOWARD SOUTH CENTRAL IL TOWARD POCKET OF STRONGEST INSTABILITY. HAVE SENT UPDATES TO FORECASTS FOR SHORT-TERM TRENDS IN THUNDERSTORM ACTIVITY LARGELY USING HRRR MODEL GUIDANCE WHICH APPEARS TO HAVE A GOOD HANDLE ON RECENT CONVECTIVE TRENDS. && .SHORT TERM...(TONIGHT) ISSUED AT 303 PM CDT SAT JUN 20 2015 THE REMNANTS OF TROPICAL STORM BILL DEFINED BY 1006 MB SURFACE LOW OVER SOUTHERN OHIO WITH 580 DM 500 MB LOW WILL TRACK INTO THE MID ATLANTIC STATES BY DAWN SUNDAY. BROKEN TO OVERCAST CLOUDS 1.5-3K FT OVER EASTERN HALF OF CWA WILL CONTINUE TO DECREASE FROM WEST TO EAST DURING LATE AFTERNOON AND EARLY EVENING. A CAPPED ATMOSPHERE IS KEEPING CENTRAL AND SOUTHEAST IL DRY SO FAR TODAY. HOWEVER, SHOWERS AND THUNDERSTORMS OVER EASTERN IA AND TRACKING EAST INTO NW IL AND SW WI MAINLY NORTH OF I-80 WILL EVOLVE INTO A LARGER MCS SYSTEM THAT WILL DROP SE TOWARD THE IL RIVER LATE THIS AFTERNOON/EARLY EVENING AND ACROSS MOST OF CENTRAL IL DURING THIS EVENING, REACHING SOUTHEAST IL OVERNIGHT WHERE CONVECTION CHANCES LOWER TO 30% FROM I-70 SOUTH. SPC HAS SLIGHT RISK OF SEVERE STORMS AS FAR SE AS A TAYLORVILLE TO DANVILLE LINE TONIGHT WHILE ENHANCED RISK WAS EXPANDED SE TO NEAR THE IL RIVER. AREAS WEST OF IL RIVER HAVE 30% RISK OF LARGE HAIL (2 INCH DIAMETER OR LARGER) AND DAMAGING WIND GUSTS ALONG WITH A 5% RISK OF TORNADOES. VERY UNSTABLE AIRMASS DEVELOPING LATE THIS AFTERNOON AND INTO THIS EVENING WITH CAPES RISING TO 2500-4500 J/KG IN WESTERN COUNTIES (EVEN NEAR 5000 J/KG BY 00Z/7 PM IN SW IA/NE MO AND FAR WEST CENTRAL IL AROUND QUINCY. MEANWHILE BULK SHEAR IS 30-40 KTS OVER NORTHERN CWA MAINLY FROM I-72 NORTH. PRECIPITABLE WATER VALUES OF 1.5-1.8 INCHES OVER IA THIS AFTERNOON TO SHIFT INTO CENTRAL IL THIS EVENING AND COULD CAUSE SOME LOCALLY HEAVY RAINS WITH THUNDERSTORMS ALONG WITH FREQUENT LIGHTNING. MUGGY LOWS TONIGHT IN THE LOWER 70S OVER CENTRAL/SE IL WITH UPPER 60S FAR NW BY GALESBURG. .LONG TERM...(SUNDAY THROUGH SATURDAY) ISSUED AT 303 PM CDT SAT JUN 20 2015 OUTFLOW BOUNDARY/FRONTAL BOUNDARY WILL REMAIN DRAPED OVER THE AREA TOMORROW AND THIS WILL BE THE FOCUS FOR ADDITIONAL SHOWERS AND THUNDERSTORMS. COULD BE SOME LINGERING THUNDERSTORMS FROM THE OVERNIGHT MCS THAT MOVES THROUGH. HOWEVER...BIG QUESTION IS HOW FAR SOUTH WILL THE OUTFLOW BOUNDARY GET BY MORNING. FORCING ALONG THE BOUNDARY AND MOISTURE WILL BE SUFFICIENT FOR MORE STORMS AND AGREE WITH SPC THAT A SLIGHT RISK IS WARRANTED OVER PARTS OF THE CWA TOMORROW THROUGH TOMORROW NIGHT. THIS BOUNDARY WILL THEN LIFT NORTHWARD A LITTLE THROUGH THE FIRST PART OF THE WEEK...SO PCPN CHANCES WILL SHIFT NORTHWARD SOME. HOWEVER...ALL MODELS FORECASTING STORMS TO CONTINUE THROUGH THE WEEK AND THIS WILL KEEP THE FRONT FROM GOING TOO FAR NORTH...AND WILL LIKELY BE OVER OR NEAR THE AREA THROUGH SATURDAY. THEREFORE...A CHANCE OF SHOWERS AND STORMS WILL CONTINUE THROUGH THE ENTIRE WEEK. THERE WILL BE SOME BREAKS IN THE PCPN...BUT TIMING OF WHEN THESE WILL BE THIS FAR OUT IS TOO UNCERTAIN. SO WILL JUST KEEP POPS THE WHOLE TIME AND THEN MAKE ADJUSTMENTS AS THE EVENTS GET CLOSER. TEMPS WILL BE WARM THROUGH THE PERIOD WITH THE WARMEST DAYS BEING MON THROUGH WED. A RELATIVELY STRONGER FRONT LOOKS TO MOVE THROUGH LATE IN THE WEEK AND THIS SHOULD BRING SLIGHTLY COOLER TEMPS FOR FRI AND SAT. GUIDANCE NUMBERS LOOK OK BUT WENT LITTLE WARMER IN THE EXTENDED THAN MEX GUIDANCE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1241 AM CDT SUN JUN 21 2015 WIDESPREAD SHRA AND SCATTERED TSRA ACROSS CENTRAL IL TERMINALS AT 06Z. EMBEDDED IFR/MVFR CONDITIONS MAINLY DUE TO LOW VISIBILITIES...HOWEVER PRIMARILY VFR CONDITIONS. PRECIPITATION/THUNDERSTORMS EXPECTED TO SHIFT SOUTHWARD OVERNIGHT AND WILL LINGER LONGEST AT KSPI-KDEC-KCMI...POTENTIALLY UNTIL AROUND 10-12Z. AS FRONTAL BOUNDARY CAUSING ACTIVITY SHIFTS BACK NORTHWARD DURING THE DAY SUNDAY...SHRA/TSRA WILL SPREAD BACK NORTHWARD ACROSS CENTRAL IL TERMINALS FROM AROUND 21-24Z AND HAVE INCLUDED VCTS BACK INTO TAFS AT THAT TIME. WINDS VARIABLE OVERNIGHT IN THE WAKE OF THUNDERSTORM ACTIVITY...TRANSITIONING BACK TO W-SW 5-10 KTS OVER NEXT SEVERAL HOURS && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ONTON SHORT TERM...07 LONG TERM...AUTEN AVIATION...ONTON
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
350 AM AM EDT SUN JUN 21 2015 .UPDATE... THE SYNOPSIS...LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 323 AM EDT SUN JUN 21 2015 A MEANDERING FRONTAL ZONE IS EXPECTED TO LINGER NEARBY FOR THE BALANCE OF THE WEEK...RESULTING IN PERIODIC THUNDERSTORM CHANCES. && .NEAR TERM /TODAY/... ISSUED AT 323 AM EDT SUN JUN 21 2015 LINE OF THUNDERSTORMS CURRENTLY MOVING THROUGH THE LOCAL AREA HAS BEEN GRADUALLY WEAKENING WITH TIME. STILL SOME POCKETS OF HIGH WINDS ASSOCIATED WITH THIS FEATURE. OUTFLOW BOUNDARY CURRENTLY EXTENDS FROM SOUTHEAST INDIANA...THROUGH FAR SOUTHERN ILLINOIS...AND THEN BACK INTO NORTHWEST MISSOURI. ADDITIONAL CONVECTION IS OCCURRING OVER WESTERN ILLINOIS/NORTHERN MISSOURI ALONG THE TAIL END OF THIS BOUNDARY. CURRENT THUNDERSTORM ACTIVITY SHOULD BE MOVING EAST OF THE AREA OVER THE NEXT COUPLE OF HOURS. THUNDERSTORM POTENTIAL LATER TODAY ALONG COLD FRONT IS LESS CLEAR CUT BASED ON CURRENT ACTIVITY. STEEP LAPSE RATES OBSERVED ON LAST EVENING/S UPPER AIR HAVE LIKELY BEEN WORKED OVER...SO THINK SEVERE POTENTIAL FOR TODAY HAS DIMINISHED. POSSIBLE SOME OF THE ACTIVITY OVER WESTERN ILLINOIS MAY MOVE INTO THE SOUTHWEST ZONES LATER THIS MORNING. MODEL DATA ALSO SUGGEST SOME DEVELOPMENT POSSIBLE ALONG THE COLD FRONT OVER ABOUT THE SOUTHERN HALF OF THE FORECAST AREA BY EARLY AFTERNOON. WILL GO WITH CHANCE POPS ALL AREAS TODAY...WITH THE HIGHEST POPS OVER THE SOUTHERN ZONES. LOW LEVEL THICKNESSES SUGGEST THE GFS MOS HIGHS FOR TODAY MAY BE TOO WARM. WILL NUDGE THE GUIDANCE HIGHS DOWN A FEW DEGREES. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... ISSUED AT 323 AM EDT SUN JUN 21 2015 MODEL DATA SUGGEST FRONT WILL STALL OUT NEAR THE OHIO RIVER FOR A TIME EARLY TONIGHT BEFORE BEGINNING TO DRIFT BACK NORTH TOWARDS MORNING. LOW LEVEL JET WILL BE FOCUSED MUCH FARTHER WEST TONIGHT...SO DON/T THINK ANY NOCTURNAL CONVECTION WILL BE WIDESPREAD. WILL CONTINUE WITH CHANCE POPS...WITH THE HIGHEST POPS IN THE SOUTH. REMNANTS OF FRONT EXPECTED TO PUSH OFF TO THE NORTHEAST DURING THE DAY ON MONDAY AS LOW PRESSURE DEVELOPS OVER THE PLAINS. LAPSE RATES AND DEEP LAYER SHEAR FAVORABLE FOR SEVERE STORMS MONDAY AND MONDAY NIGHT. HOWEVER...A GOOD FOCUS FOR CONVECTION WILL BE LACKING WITH THE BETTER FORCING FARTHER NORTH OVER THE GREAT LAKES. IT IS POSSIBLE SOME CONVECTION MAY SNEAK INTO THE AREA MONDAY NIGHT FROM THE NORTH OR NORTHWEST. BASED ON ABOVE...WILL CONTINUE WITH CHANCE POPS FOR MONDAY AND MONDAY NIGHT. MODELS SUGGEST ANOTHER COLD FRONT WILL DROP INTO THE AREA ON TUESDAY...PROBABLY STALLING OUT NEAR THE OHIO RIVER TUESDAY NIGHT. WILL GO WITH CHANCE POPS AT THOSE TIMES AS WELL. BASED ON PROGGED LOW LEVEL THICKNESSES...THE GFS TEMPERATURE GUIDANCE IN THE LATER PERIODS OF THE SHORT TERM LOOK OK AT THIS POINT. ONLY MINOR ADJUSTMENTS PLANNED. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... ISSUED AT 350 AM EDT SUN JUN 21 2015 A FLAT UPPER RIDGE OVER THE SOUTHERN U.S. WILL RETROGRADE BACK INTO THE ROCKIES WHICH WILL ALLOW AN UPPER TROUGH TO DIG INTO THE GREAT LAKES BY NEXT WEEKEND. ACTIVE WEATHER WILL CONTINUE THROUGH THIS PERIOD AS A FRONTAL SYSTEM REMAINS ACROSS OUR AREA AND A SERIES OF SYSTEMS TRACK EAST SOUTHEAST ACROSS OUR REGION WITH THE MOST SIGNIFICANT ONES BEING EARLY THURSDAY AND SATURDAY. MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. WENT WITH CHANCE POPS MOST PERIODS WITH LIKELY POPS ACROSS OUR NORTH WEDNESDAY NIGHT AND SLIGHT CHANCE POPS MOST AREAS FRIDAY. TEMPERATURES WILL BE NEAR SEASONAL VALUES EARLY ON...BUT WILL BECOME COOLER TOWARDS NEXT WEEKEND. && .AVIATION /DISCUSSION FOR 210600Z TAF ISSUANCE/... ISSUED AT 1244 AM EDT SUN JUN 21 2015 RAPID REFRESH AND RADAR TRENDS SUGGEST EASTERN ILLINOIS BOW ECHO WILL BE NEAR LAF AND HUF AROUND 06Z AND TO IND AND BMG AROUND 08Z. SO...WILL HAVE A TEMPO MVFR THUNDERSTORM GROUP FOR AN HOUR OR TWO AT EACH SITE AND ALSO A WIND SHIFT TO NORTHWEST WITH GUSTS TO 40 KNOTS. AFTER THAT...COVERAGE LOOKS TO LOW TO MENTION ANY SHOWERS OR THUNDERSTORMS. MODEL RH TIME SECTIONS WERE THEN SHOWING AN INCREASE IN NEAR SURFACE MOISTURE THROUGH THE REST OF THE OVERNIGHT AND TIL AROUND 15Z. SO...COULD SEE STRATUS BEHIND THE CONVECTIVE ACTIVITY...BUT NOT CONFIDENT ENOUGH TO GO WITH CEILINGS WITH LACK OF STRONG LOW LEVEL INVERSION PER RAP SOUNDINGS. WILL TIME THE COLD FRONT TO LAF AROUND 15Z...IND AND HUF AROUND 18Z AND BMG AROUND 00Z. SOUTHWEST WINDS AROUND KNOTS WILL SHIFT TO NORTHWEST BEHIND THE FRONT AND BECOMING LIGHT AFTER DARK. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JAS NEAR TERM...JAS SHORT TERM...JAS LONG TERM...JH AVIATION...MK/JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
327 AM EDT SUN JUN 21 2015 .UPDATE... THE SYNOPSIS...NEAR TERM AND SHORT TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 323 AM EDT SUN JUN 21 2015 A MEANDERING FRONTAL ZONE IS EXPECTED TO LINGER NEARBY FOR THE BALANCE OF THE WEEK...RESULTING IN PERIODIC THUNDERSTORM CHANCES. && .NEAR TERM /TODAY/... ISSUED AT 323 AM EDT SUN JUN 21 2015 LINE OF THUNDERSTORMS CURRENTLY MOVING THROUGH THE LOCAL AREA HAS BEEN GRADUALLY WEAKENING WITH TIME. STILL SOME POCKETS OF HIGH WINDS ASSOCIATED WITH THIS FEATURE. OUTFLOW BOUNDARY CURRENTLY EXTENDS FROM SOUTHEAST INDIANA...THROUGH FAR SOUTHERN ILLINOIS...AND THEN BACK INTO NORTHWEST MISSOURI. ADDITIONAL CONVECTION IS OCCURRING OVER WESTERN ILLINOIS/NORTHERN MISSOURI ALONG THE TAIL END OF THIS BOUNDARY. CURRENT THUNDERSTORM ACTIVITY SHOULD BE MOVING EAST OF THE AREA OVER THE NEXT COUPLE OF HOURS. THUNDERSTORM POTENTIAL LATER TODAY ALONG COLD FRONT IS LESS CLEAR CUT BASED ON CURRENT ACTIVITY. STEEP LAPSE RATES OBSERVED ON LAST EVENING/S UPPER AIR HAVE LIKELY BEEN WORKED OVER...SO THINK SEVERE POTENTIAL FOR TODAY HAS DIMINISHED. POSSIBLE SOME OF THE ACTIVITY OVER WESTERN ILLINOIS MAY MOVE INTO THE SOUTHWEST ZONES LATER THIS MORNING. MODEL DATA ALSO SUGGEST SOME DEVELOPMENT POSSIBLE ALONG THE COLD FRONT OVER ABOUT THE SOUTHERN HALF OF THE FORECAST AREA BY EARLY AFTERNOON. WILL GO WITH CHANCE POPS ALL AREAS TODAY...WITH THE HIGHEST POPS OVER THE SOUTHERN ZONES. LOW LEVEL THICKNESSES SUGGEST THE GFS MOS HIGHS FOR TODAY MAY BE TOO WARM. WILL NUDGE THE GUIDANCE HIGHS DOWN A FEW DEGREES. && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... ISSUED AT 323 AM EDT SUN JUN 21 2015 MODEL DATA SUGGEST FRONT WILL STALL OUT NEAR THE OHIO RIVER FOR A TIME EARLY TONIGHT BEFORE BEGINNING TO DRIFT BACK NORTH TOWARDS MORNING. LOW LEVEL JET WILL BE FOCUSED MUCH FARTHER WEST TONIGHT...SO DON/T THINK ANY NOCTURNAL CONVECTION WILL BE WIDESPREAD. WILL CONTINUE WITH CHANCE POPS...WITH THE HIGHEST POPS IN THE SOUTH. REMNANTS OF FRONT EXPECTED TO PUSH OFF TO THE NORTHEAST DURING THE DAY ON MONDAY AS LOW PRESSURE DEVELOPS OVER THE PLAINS. LAPSE RATES AND DEEP LAYER SHEAR FAVORABLE FOR SEVERE STORMS MONDAY AND MONDAY NIGHT. HOWEVER...A GOOD FOCUS FOR CONVECTION WILL BE LACKING WITH THE BETTER FORCING FARTHER NORTH OVER THE GREAT LAKES. IT IS POSSIBLE SOME CONVECTION MAY SNEAK INTO THE AREA MONDAY NIGHT FROM THE NORTH OR NORTHWEST. BASED ON ABOVE...WILL CONTINUE WITH CHANCE POPS FOR MONDAY AND MONDAY NIGHT. MODELS SUGGEST ANOTHER COLD FRONT WILL DROP INTO THE AREA ON TUESDAY...PROBABLY STALLING OUT NEAR THE OHIO RIVER TUESDAY NIGHT. WILL GO WITH CHANCE POPS AT THOSE TIMES AS WELL. BASED ON PROGGED LOW LEVEL THICKNESSES...THE GFS TEMPERATURE GUIDANCE IN THE LATER PERIODS OF THE SHORT TERM LOOK OK AT THIS POINT. ONLY MINOR ADJUSTMENTS PLANNED. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ISSUED AT 216 PM EDT SAT JUN 20 2015 MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL REMAIN ACROSS THE SOUTH AND SOUTHWEST USA DURING MUCH OF THE LONG TERM...SETTING UP A NORTHWEST FLOW ALOFT ACROSS CENTRAL INDIANA. BY NEXT WEEKEND A TROUGH MAY DIG INTO THE AREA. THIS FLOW WILL ALLOW A SURFACE FRONT TO STALL OUT ACROSS CENTRAL INDIANA THROUGH THE EXTENDED. AS UPPER WAVES INTERACT WITH THE FRONT...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH DAY. MORE RAIN WILL BE POSSIBLE WITH THE UPPER TROUGH SATURDAY. TEMPERATURES WILL REMAIN NEAR TO ABOVE AVERAGE THROUGH MUCH OF THE PERIOD...WITH SOME COOLER CONDITIONS PERHAPS ARRIVING FOR NEXT WEEKEND. && .AVIATION /DISCUSSION FOR 210600Z TAF ISSUANCE/... ISSUED AT 1244 AM EDT SUN JUN 21 2015 RAPID REFRESH AND RADAR TRENDS SUGGEST EASTERN ILLINOIS BOW ECHO WILL BE NEAR LAF AND HUF AROUND 06Z AND TO IND AND BMG AROUND 08Z. SO...WILL HAVE A TEMPO MVFR THUNDERSTORM GROUP FOR AN HOUR OR TWO AT EACH SITE AND ALSO A WIND SHIFT TO NORTHWEST WITH GUSTS TO 40 KNOTS. AFTER THAT...COVERAGE LOOKS TO LOW TO MENTION ANY SHOWERS OR THUNDERSTORMS. MODEL RH TIME SECTIONS WERE THEN SHOWING AN INCREASE IN NEAR SURFACE MOISTURE THROUGH THE REST OF THE OVERNIGHT AND TIL AROUND 15Z. SO...COULD SEE STRATUS BEHIND THE CONVECTIVE ACTIVITY...BUT NOT CONFIDENT ENOUGH TO GO WITH CEILINGS WITH LACK OF STRONG LOW LEVEL INVERSION PER RAP SOUNDINGS. WILL TIME THE COLD FRONT TO LAF AROUND 15Z...IND AND HUF AROUND 18Z AND BMG AROUND 00Z. SOUTHWEST WINDS AROUND KNOTS WILL SHIFT TO NORTHWEST BEHIND THE FRONT AND BECOMING LIGHT AFTER DARK. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JAS NEAR TERM...JAS SHORT TERM...JAS LONG TERM...50 AVIATION...MK/JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1244 AM EDT SUN JUN 21 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 328 PM EDT SAT JUN 20 2015 A REMNANT TROPICAL SYSTEM WILL CONTINUE TO PUSH EASTWARD INTO TONIGHT. THEN A FRONTAL SYSTEM WILL MOVE INTO THE AREA EARLY SUNDAY AND LINGER INTO NEXT WEEK...RESULTING IN MORE PERIODIC THUNDERSTORM CHANCES. && .NEAR TERM /REST OF TONIGHT/... ISSUED AT 1007 PM EDT SAT JUN 20 2015 UPDATE... CURRENT FORECAST IS ON TRACK...SO NO CHANGES. LATEST RADAR MOSAIC SHOWS WIDESPREAD SHOWERS AND THUNDERSTORMS CURRENTLY TRACKING ACROSS CENTRAL AND NORTHERN ILLINOIS. NORTHWESTERN PORTIONS OF CENTRAL INDIANA COULD START SEEING SOME PRECIP WITHIN THE NEXT FEW HOURS WITH THE BULK OF THE CONVECTION MOVING IN AFTER MIDNIGHT. THE ONLY COUNTY STILL UNDER SLIGHT RISK OF SEVERE WEATHER IS WARREN COUNTY. UPDATED GRIDS HAVE BEEN SENT. PREVIOUS DISCUSSION... AN UPPER LEVEL SYSTEM IS SLOWLY MOVING SOUTHEASTWARD ACROSS PORTIONS OF EASTERN IOWA AND WESTERN WISCONSIN AND IS EXPECTED TO APPROACH THE NORTHWEST COUNTIES OF CENTRAL INDIANA AROUND MIDNIGHT TONIGHT. GUIDANCE SEEMS TO BE IN AGREEMENT WITH INITIALLY SHOWING THIS SYSTEM TO BE QUITE PROGRESSIVE AS IT MOVES TOWARD THE CENTRAL CWA DURING THE WEE EARLY HOURS SUNDAY MORNING...THEN BEGINS TO SLOW DOWN AND POSSIBLY EVEN STALL OUT AS IT DROPS SOUTH OF THE I 70 CORRIDOR. TRIED TO DEPICT POPS IN THE FORECAST AS IN THE HRRR AND OTHER NEAR TERM GUIDANCE WITH HIGHER POPS ACROSS THE NORTHWEST SHORTLY AFTER MIDNIGHT...THEN SLOWLY MOVING THIS SYSTEM SOUTHEAST ACROSS THE FORECAST AREA OVERNIGHT TIL IT REACHES THE SOUTHERN TWO TO THREE TIERS OF COUNTIES OF THE CWA AND EITHER SLOWS DOWN...WEAKENS...OR ALL TOGETHER JUST STALLS OUT AND LATER WEAKENS. SEVERE WX THREAT FOR TONIGHT VERY MARGINAL WITH ONLY WARREN COUNTY INCLUDED IN SPC/S DAY 1 SLIGHT RISK. SO SOME OF THESE STORMS DO HAVE THE POTENTIAL TO BE STRONG WITH DAMAGING WINDS AND HAIL AS THE MAIN THREATS. AND HEAVY DOWNPOURS AND CLOUD-TO-GROUND LIGHTNING NOT TO BE DISCOUNTED IN ANY THUNDERSTORMS. A BLEND OF GUIDANCE FOR LOW TEMPERATURES TONIGHT SEEMS REASONABLE AS THE NUMBERS ARE COMING IN SIMILAR FOR LOWS AROUND 70. && .SHORT TERM /SUNDAY THROUGH TUESDAY/... ISSUED AT 328 PM EDT SAT JUN 20 2015 A COLD FRONT WILL BEGIN MOVING INTO THE AREA LATER SUNDAY AFTERNOON FOLLOWING THE UPPER LEVEL SYSTEM MOVING SOUTHEAST ACROSS THE FORECAST AREA THAT MORNING. STEEP LAPSE RATES AND SUFFICIENT DEEP LAYER SHEAR SUGGEST AN ORGANIZED SEVERE THREAT IS POSSIBLE WITH THE FRONT...AND THE MAIN FOCUS FOR ANY STRONG TO SEVERE STORMS AS BEEN SHUNTED SOUTHWARD BASED ON THE FASTER TIMING OF THIS SYSTEM...SO NOW THE ONLY COUNTIES IN THE DAY 2 SLIGHT RISK FOR KIND CWA LIE JUST SOUTH OF THAT COMMON DIVIDING LINE THAT IT THE I 70 CORRIDOR. BASICALLY KEEPING HIGHER CHANCE POPS ACROSS THIS AREA TO THE SOUTH AND ONLY SLIGHT CHANCE TO ZERO POPS ACROSS THE NORTHERN COUNTIES. LATER SUNDAY NIGHT THE FRONT MAY SAG FAR ENOUGH TO THE SOUTH FOR A LULL IN THE THUNDERSTORM THREAT...BUT WILL KEEP SOME SMALL/WEAK CHANCES FOR POPS GOING SUNDAY NIGHT IN CASE THE FRONT ENDS UP MORE STATIONARY. APPEARS THE FRONT WILL BEGIN DRIFTING BACK TO THE NORTH DURING MONDAY AND TUESDAY SO WILL CONTINUE TO GO WITH PERIODIC CHANCES FOR SHOWERS AND THUNDERSTORMS BOTH DAYS. ALSO BASED ON PROGGED LOW LEVEL THICKNESSES...APPEARS TEMPERATURES AND DEW POINTS WILL BE GETTING INTO THAT UNCOMFORTABLE RANGE AGAIN WITH DEW POINTS IN THE MID 70S (OR HIGHER EVEN?) POSSIBLE...AND HIGHS IN THE MID/UPPER 80S TO AROUND 90 ACROSS THE SOUTHERN HALF OF THE CWA. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ISSUED AT 216 PM EDT SAT JUN 20 2015 MODELS ARE CLOSE ENOUGH THAT THE SUPERBLEND INITIALIZATION WAS ACCEPTED FOR MOST ITEMS. AN UPPER RIDGE WILL REMAIN ACROSS THE SOUTH AND SOUTHWEST USA DURING MUCH OF THE LONG TERM...SETTING UP A NORTHWEST FLOW ALOFT ACROSS CENTRAL INDIANA. BY NEXT WEEKEND A TROUGH MAY DIG INTO THE AREA. THIS FLOW WILL ALLOW A SURFACE FRONT TO STALL OUT ACROSS CENTRAL INDIANA THROUGH THE EXTENDED. AS UPPER WAVES INTERACT WITH THE FRONT...SHOWERS AND THUNDERSTORMS WILL BE POSSIBLE EACH DAY. MORE RAIN WILL BE POSSIBLE WITH THE UPPER TROUGH SATURDAY. TEMPERATURES WILL REMAIN NEAR TO ABOVE AVERAGE THROUGH MUCH OF THE PERIOD...WITH SOME COOLER CONDITIONS PERHAPS ARRIVING FOR NEXT WEEKEND. && .AVIATION /DISCUSSION FOR 210600Z TAF ISSUANCE/... ISSUED AT 1244 AM EDT SUN JUN 21 2015 RAPID REFRESH AND RADAR TRENDS SUGGEST EASTERN ILLINOIS BOW ECHO WILL BE NEAR LAF AND HUF AROUND 06Z AND TO IND AND BMG AROUND 08Z. SO...WILL HAVE A TEMPO MVFR THUNDERSTORM GROUP FOR AN HOUR OR TWO AT EACH SITE AND ALSO A WIND SHIFT TO NORTHWEST WITH GUSTS TO 40 KNOTS. AFTER THAT...COVERAGE LOOKS TO LOW TO MENTION ANY SHOWERS OR THUNDERSTORMS. MODEL RH TIME SECTIONS WERE THEN SHOWING AN INCREASE IN NEAR SURFACE MOISTURE THROUGH THE REST OF THE OVERNIGHT AND TIL AROUND 15Z. SO...COULD SEE STRATUS BEHIND THE CONVECTIVE ACTIVITY...BUT NOT CONFIDENT ENOUGH TO GO WITH CEILINGS WITH LACK OF STRONG LOW LEVEL INVERSION PER RAP SOUNDINGS. WILL TIME THE COLD FRONT TO LAF AROUND 15Z...IND AND HUF AROUND 18Z AND BMG AROUND 00Z. SOUTHWEST WINDS AROUND KNOTS WILL SHIFT TO NORTHWEST BEHIND THE FRONT AND BECOMING LIGHT AFTER DARK. && .IND WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SYNOPSIS...SMF NEAR TERM...SMF/TDUD SHORT TERM...SMF LONG TERM...50 AVIATION...MK/JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
645 PM CDT MON JUN 22 2015 .UPDATE... ISSUED AT 644 PM CDT MON JUN 22 2015 VOLATILE SEVERE WEATHER ENVIRONMENT CONTINUES OVER THE FORECAST AREA THIS EVENING. SURFACE BOUNDARY FROM DIFFERENTIAL HEATING AND OUTFLOW FROM EARLIER MCS WAS ROUGHLY ALONG THE I-890 CORRIDOR OVER NW IL INTO EASTERN IA...SEPARATING TEMPERATURES IN THE UPPER 70S TO AROUND 80 TO THE NORTH...WHILE LOWER TO MID 80S WERE FOUND TO THE SOUTH. DEEP MODERATE TO STRONG SHEAR WAS OVER THE ENTIRE AREA...WHILE DEWPOINTS IN THE MID 70S WAS LEADING TO SBCAPE VALUES IN THE 4500 TO NEAR 6000 J/KG ON THE WARM SIDE OF THE BOUNDARY. SO FAR THE ENVIRONMENT HAS BEEN DOMINATED BY A STRONG TORNADIC SUPERCELL TRACKING W AND SW OF OTM...BUT WILL CONTINUE TO MONITOR TRENDS WITH MORE DISORGANIZED STORMS ALONG AND SE OF A LINE FROM CLINTON THROUGH IOWA CITY TO OTTUMWA. WILL BE MOST CLOSELY WATCHING STORMS ALONG THE AFOREMENTIONED EAST TO WEST BOUNDARY...AND THE CLUSTER IN THE FAR SW...THAT WILL HAVE THE MOST LIKELIHOOD TO PRODUCE SEVERE WEATHER AND A TORNADO WATCH REMAINS IN EFFECT FOR ALL BUT THE FAR NORTHERN ROW OF COUNTIES UNTIL 03Z. THE MAIN COLD FRONT AT 00Z ROUGHLY BISECTED IA FROM NE TO SW...AND WILL END THE THUNDERSTORM THREAT AS IT MOVES THROUGH LATER THIS EVENING AND THE FORECAST REMAINS ON TRACK. && .SYNOPSIS... ISSUED AT 355 PM CDT MON JUN 22 2015 BOW ECHO THAT PRODUCED 70 TO 90 MPH DESTRUCTIVE WINDS ACROSS OUR FAR NORTHERN COUNTIES THIS MORNING HAS LEFT A RAIN COOLED BOUNDARY NORTH OF I-80. STRONG MOISTURE TRANSPORT AND STRONG SHEAR HAD DEVELOPED AN ISOLATED ELEVATED SEVERE THUNDERSTORM EARLY THIS AFTERNOON IN THE CEDAR RAPIDS AREA...WITH HAIL UP TO BASEBALL SIZE. ISOLATED ELEVATED THUNDERSTORMS WITH MAINLY VERY LARGE HAIL WILL CONTINUE TO FESTER THROUGH THE AFTERNOON. WITH THE CLOUD COVER I HAVE LOWERED TEMPERATURES AND DEWPOINTS SEVERAL DEGREES. LATER THIS AFTERNOON THROUGH THE EVENING...STRONG COLD FRONT IN NW IA WILL BE PUSHING INTO OUR FAR NW CWA BY EVENING. DEWPOINTS WERE IN THE 40S WITH GUSTY NW WINDS BEHIND THE FRONT. CAPES WILL BUILD AS THE AFTERNOON PROGRESSES WITH STORMS BECOMING SURFACE BASED. THE HRRR DEVELOPS DISCRETE SUPERCELLS NEAR HIGHWAY 30 BY MID TO LATE AFTERNOON THEN PROGRESSING SOUTHEAST AND FORMING INTO ANOTHER BOW ECHO. THESE STORMS WILL PRODUCE VERY LARGE HAIL AND A FEW TORNADOES TRANSITIONING TO WIDESPREAD DAMAGING WINDS OF 70+ MPH AS IT PUSHES INTO OUR SOUTHERN AND EASTERN COUNTIES. TO SAY THE LEAST THIS IS ANOTHER DANGEROUS SEVERE WEATHER SITUATION UNFOLDING. THE SEVERE THREAT WILL END WITH THE PASSAGE OF THE FRONT AND SHOULD BE PRETTY MUCH OVER WITH IN THE DVN CWA BY MIDNIGHT. 3 PM TEMPERATURES RANGED FROM THE LOWER 70S IN RAIN AREAS IN OUR NORTH TO THE MID 80S SOUTH. DEWPOINTS WERE IN THE 70S. SPC MESO ANALYSIS INDICATED SBCAPES OF 6000 J/KG IN NW MO WITH A TIGHT GRADIENT OVER EASTERN IA (BEWARE OF THE GRADIENT). EFFECTIVE BULK SHEAR WAS 70 KNOTS...HELICITY 300 M2/S2 WITH 1 KM EHI OF 5. STRONG 850 MB MOISTURE TRANSPORT WAS EVIDENT ALONG WITH PWAT`S OF NEARLY 2 INCHES. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 355 PM CDT MON JUN 22 2015 FORECAST FOCUS ON SEVERE WEATHER THIS EVENING THEN BRIEFLY QUIET ON TUESDAY. TONIGHT...MOST OF THE DETAILS WERE NOTED IN THE SYNOPSIS SECTION ABOVE BUT THE MAIN MESSAGE WILL BE THE SEVERE WEATHER THREAT WILL END BY 10 OR 11 PM. THIS IS DUE TO A COLD FRONT MOVING ACROSS THE CWA AS WINDS TURN NORTHWEST...USHERING COOLER AND LESS HUMID AIR INTO THE AREA. MINIMUM TEMPERATURES WILL RANGE AROUND 60 ALONG HIGHWAY 20 TO THE UPPER 60S FAR SOUTH. TUESDAY...WEAK HIGH PRESSURE WILL PROVIDE A RATHER PLEASANT DAY WITH COMFORTABLE HUMIDITY AND COOLER TEMPERATURES...WITH NORTH WINDS AROUND 10 MPH. DEWPOINTS SHOULD BE IN THE 50S WITH AFTERNOON HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 355 PM CDT MON JUN 22 2015 FORECAST FOCUS ON THUNDERSTORMS RETURNING TUESDAY NIGHT THROUGH MOST OF THE REMAINDER OF THE WEEK...THEN COOLER BY THE WEEKEND. TUESDAY NIGHT THROUGH FRIDAY...FRONTAL BOUNDARY RETURNS AS A WARM FRONT TUESDAY NIGHT WITH A CHANCE OF STORMS IN OUR FAR SOUTH. ON WEDNESDAY THE FRONT LOOKS TO STALL OVER THE DVN WITH THE POTENTIAL FOR HEAVY RAINFALL AND SEVERE WEATHER AGAIN. SPC HAS THE ENTIRE CWA IN A SLIGHT RISK. DEWPOINTS WILL BE RISING WELL INTO THE 60S TO LOWER 70S WITH AFTERNOON MAXIMUM TEMPERATURES IN THE UPPER 70S NORTH TO UPPER 80S SOUTH. THE ECMWF SUGGESTS THE FRONT TO DROP SOUTHWARD LATE IN THE WEEK WITH ONLY OUR FAR SOUTH STILL HAVING A CHANCE OF STORMS. THE GFS HAS THE FRONT WELL TO OUR SOUTH WITH DRY WEATHER BY FRIDAY. THIS WEEKEND...NORTHWEST TO NORTH FLOW ALOFT WITH COMFORTABLE TEMPERATURES AND HUMIDITY AND MAINLY DRY. HIGHS WILL BE IN THE 70S TO NEAR 80 WITH LOWS AROUND 60. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 644 PM CDT MON JUN 22 2015 THUNDERSTORMS...SOME SEVERE WITH DAMAGING WINDS AND LARGE HAIL WILL BE POSSIBLE OVER ESPECIALLY THE MLI AND BRL TERMINALS UNTIL A COLD FRONT MOVES THROUGH LATER THIS EVENING. SW WINDS WILL BE GUSTY AT TIMES AHEAD OF THE FRONT...THEN CHANGE TO THE NW AND DIMINISH TO LESS THAN 10 KTS BEHIND THE FRONT...ACCOMPANIED BY CLEARING SKIES. CONDITIONS WILL THEN REMAIN VFR WITH LIGHT WINDS THROUGH TUESDAY. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...SHEETS SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...HAASE AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1249 PM CDT SUN JUN 21 2015 .UPDATE... ISSUED AT 650 AM CDT SUN JUN 21 2015 DENSE FOG HAS FORMED IN THE AREAS THAT THE MOST RAIN YESTERDAY ALONG WITH WHERE THE ANVIL FROM THE CONVECTION HAD MOVED OUT OF THE AREA. AS A RESULT A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9AM TODAY. OTHERWISE DECAYING CONVECTION TO THE WEST MAY MAKE IT INTO THE AREA THIS AFTERNOON AS SPRINKLES OR LIGHT RAIN. THE HRRR HAS CONSISTENTLY FORECAST THIS. MY CONFIDENCE IS LOW IN THIS OCCURRING SO DECIDED TO LEAVE IT OUT. OTHERWISE NO UPDATES TO THE FORECAST WERE MADE. && .SYNOPSIS... ISSUED AT 327 AM CDT SUN JUN 21 2015 A MCS THAT MOVED THROUGH THE AREA ON SATURDAY EVENING HAD STALLED OUT JUST SOUTH OF THE CWA. MOST OF THE RAIN WAS OVER ACROSS THE AREA. 24 MPE SUGGESTS THAT THERE WERE 2 AREAS OF 1 TO 2 INCH RAINFALL ACROSS THE AREA TODAY. I80 WAS THE SEPARATION BETWEEN THESE TWO AREAS. DENSE FOG HAS DEVELOPED ACROSS THE THE NW ZONES AS LIGHT WIND AN AMPLE MOISTURE WAS LEADING TO FOG DEVELOPMENT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 327 AM CDT SUN JUN 21 2015 MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST ARE THE CHANCES FOR POPS TONIGHT INTO MONDAY MORNING. OVERALL CHANCES APPEAR TO BE LOW FOR SCATTERED THUNDERSTORMS ON WHATEVER BOUNDARY DECIDES TO COALESCE AND MOVE NORTH AS A WARM FRONT OVERNIGHT. TODAY WILL BE A NICE DAY THAT WILL LEAD TO DRYING OUT ACROSS THE AREA. TEMPERATURES WILL BE WARM. THE BOUNDARY...OR LACK THERE OF...IS THE MAIN FORECAST PROBLEM. A PURELY MESOSCALE ISSUE PREDICTED BY SYNOPTIC MODELS USUALLY IS A DIFFICULT FORECAST. LOOKING AT MSAS THERE APPEARS TO BE DRIER AIR SINKING INTO THE AREA FROM THE NORTH. CONVECTION TO THE SOUTH OF US WILL LIKELY DIE OUT THIS MORNING LEAVING OFBS. THROUGH DIFFERENTIAL HEATING...THIS AREA SHOULD BE WHERE THE BOUNDARY SHOULD EXIST. A LOW PRESSURE....MOVING OUT OF SOUTH DAKOTA WILL FORCE THIS BOUNDARY NORTH OVERNIGHT. WE WILL RESIDE WELL INTO THE WARM SECTOR. HIRES MESO MODELS...SUGGEST LITTLE TO NO STORM COVERAGE OVERNIGHT TONIGHT. WENT WITH SCATTERED POPS...BUT DO BELIEVE IT MAY BE VERY ISOLATED OR NON-EXISTENT...JUST DO NOT HAVE THE CONFIDENCE TO GO THAT WAY YET. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 327 AM CDT SUN JUN 21 2015 SEASONABLY WARM WITH POTENTIALLY SIGNIFICANT RAINS MID WEEK AND THEN TURNING COOLER. LONG TERM FORECAST CONFIDENCE ASSESSMENT...FAIR OR AVERAGE OVERALL EXCEPT POOR WED/THU WITH WAVE AND TIMING AND PLACEMENT OF HEAVY RAINS DUE TO POOR PHYSICS ISSUES OF ALL SOLUTIONS. CONCEPTUAL TRENDS SUGGEST HEAVIEST PRECIPITATION WOULD TEND TO BE FURTHER SOUTH THAN MOST SOLUTIONS. OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH AGAIN DISPLACED SOUTHWARD CONVECTION FROM SOLUTIONS NOTED THAT SUPPORTS THIS AS AN ONGOING CONCERN FOR MID WEEK DUE TO BL MOISTURE IMBALANCES AS IS COMMON. RUN TO RUN CONTINUITY SUPPORTS A 70/30 MIX OF GFS TO HI-RES ECMWF ON FORCING AND THEN TRY AND APPLY ECMWF RAIN PACKAGE. MONDAY AND MONDAY NIGHT...VERY WARM...BREEZY AND HUMID WITH HIGHS MOSTLY 85 TO 90 SUGGESTED WITH A CONCERN NORTH SECTIONS MAY BE COOLER FROM MCS NEAR OR JUST NORTH OF HIGHWAY 20 FOR LATER SHIFTS TO MONITOR SINCE TENDENCY IS FOR GUIDANCE SOLUTIONS TO DISPLACE RAINS TOO FAR NORTH. POPS IN NORTH MAY BE A BIT TOO LOW WITH POPS SOUTH OF I-80 MAY BE TOO HIGH BASED ON JET AXIS AND 850 PARAMETERS. TUESDAY AND TUESDAY NIGHT...WEAK HIGH PRESSURE TO RESULT IN A FAIR DAY AND MOSTLY DRY TO DRY AND LOWERED HIGH TEMPERATURES AND DEWPOINTS. LATER SHIFTS MAY NEED TO LOWER DEWPOINTS FURTHER IN NORTH SECTIONS. TUESDAY NIGHT...REGION FAVORED TO EXPERIENCE LATE AN MCS WITH HEAVIEST RAINS ALONG AND SOUTH OF HIGHWAY 34. POPS MAY NEED RAISING WHEN TIMING ISSUES ARE BETTER RESOLVED WITH 1+ INCH AMOUNTS SUGGESTED AND LOW TO MARGINAL RISK OF SEVERE. WEDNESDAY...LOTS OF CLOUDS AND PRECIPITATION WITH HEAVIEST PRECIPITATION TO BE ALONG AND ESPECIALLY SOUTH OF I-80. FORCING AND MOISTURE PROFILES FAVOR WIDESPREAD .5 TO 1.5+ AMOUNTS WITH LOCALLY 2 TO 3 INCHES THAT COMBINED WITH TUESDAY NIGHT EVENT COULD RESULT IN RENEWED HYDRO ISSUES. SEVERE RISK APPEARS WILL BE ALONG AND MAYBE SOUTH OF IA/MO BORDER. HIGH TEMPERATURES BASED ON THIS PATTERN MAY NEED LOWERING BY LATER SHIFTS BY UP TO 5 DEGREES. LOWS ALSO WITH EVAPORATIVE COOLING MAY NEED LOWERING. THURSDAY THROUGH SATURDAY...BECOMING COOLER AND LESS HUMID AND MOSTLY DRY TO DRY AS NORTHWEST FLOW PATTERN DEVELOPS. HIGHS MID 70S TO LOWER 80S AND MINS UPPER 50S TO LOWER 60S WITH MODERATE HUMIDITY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1234 PM CDT SUN JUN 21 2015 RATHER DIFFUSE SURFACE PATTERN WITH WEAK RIDGING AND WINDS LINGERING THIS AFTERNOON. BOUNDARY NORTH OF I-70 AND MOISTURE TRANSPORT LIKELY TO MAINTAIN FOCUS FOR STORMS JUST SOUTH OF BRL FROM NORTHERN KS THROUGH NORTHERN MO INTO EARLY EVENING. THE BOUNDARY WILL BEGIN TO LIFT BACK NORTH THROUGH THE REGION TONIGHT AND MONDAY AND WILL BE ACCOMPANIED BY CHANCES FOR SHOWERS AND STORMS. COVERAGE LOOKS TO REMAIN GENERALLY ISOLATED TO SCATTERED LATER TONIGHT MAKING FOR LOWER CONFIDENCE ON IMPACT AT TERMINALS AND THE REASON FOR LEAVING OUT ANY MENTION WITH 18Z TAFS. ABUNDANT LOW LEVEL MOISTURE AHEAD OF RETREATING FRONT MAY LEAD TO SOME FOG AND POSSIBLY LOW CLOUDS WITH IFR/MVFR CONDITIONS LATE TONIGHT THROUGH MID MORNING MONDAY. COULD THEN SEE A BETTER CHANCE OF STORMS MONDAY MORNING NORTH AND POSSIBLY WEST OF I-80 WITH WEAKENING COMPLEX... AND HAVE INTRODUCED PROB30 GROUPS AT CID AND DBQ. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...GIBBS SYNOPSIS...GIBBS SHORT TERM...GIBBS LONG TERM...NICHOLS AVIATION...05
AREA FORECAST DISCUSSION...UPDATED
NWS QUAD CITIES IA IL
656 AM CDT SUN JUN 21 2015 .UPDATE... ISSUED AT 650 AM CDT SUN JUN 21 2015 DENSE FOG HAS FORMED IN THE AREAS THAT THE MOST RAIN YESTERDAY ALONG WITH WHERE THE ANVIL FROM THE CONVECTION HAD MOVED OUT OF THE AREA. AS A RESULT A DENSE FOG ADVISORY IS IN EFFECT UNTIL 9AM TODAY. OTHERWISE DECAYING CONVECTION TO THE WEST MAY MAKE IT INTO THE AREA THIS AFTERNOON AS SPRINKLES OR LIGHT RAIN. THE HRRR HAS CONSISTENTLY FORECAST THIS. MY CONFIDENCE IS LOW IN THIS OCCURRING SO DECIDED TO LEAVE IT OUT. OTHERWISE NO UPDATES TO THE FORECAST WERE MADE. && .SYNOPSIS... ISSUED AT 327 AM CDT SUN JUN 21 2015 A MCS THAT MOVED THROUGH THE AREA ON SATURDAY EVENING HAD STALLED OUT JUST SOUTH OF THE CWA. MOST OF THE RAIN WAS OVER ACROSS THE AREA. 24 MPE SUGGESTS THAT THERE WERE 2 AREAS OF 1 TO 2 INCH RAINFALL ACROSS THE AREA TODAY. I80 WAS THE SEPARATION BETWEEN THESE TWO AREAS. DENSE FOG HAS DEVELOPED ACROSS THE THE NW ZONES AS LIGHT WIND AN AMPLE MOISTURE WAS LEADING TO FOG DEVELOPMENT. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 327 AM CDT SUN JUN 21 2015 MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST ARE THE CHANCES FOR POPS TONIGHT INTO MONDAY MORNING. OVERALL CHANCES APPEAR TO BE LOW FOR SCATTERED THUNDERSTORMS ON WHATEVER BOUNDARY DECIDES TO COALESCE AND MOVE NORTH AS A WARM FRONT OVERNIGHT. TODAY WILL BE A NICE DAY THAT WILL LEAD TO DRYING OUT ACROSS THE AREA. TEMPERATURES WILL BE WARM. THE BOUNDARY...OR LACK THERE OF...IS THE MAIN FORECAST PROBLEM. A PURELY MESOSCALE ISSUE PREDICTED BY SYNOPTIC MODELS USUALLY IS A DIFFICULT FORECAST. LOOKING AT MSAS THERE APPEARS TO BE DRIER AIR SINKING INTO THE AREA FROM THE NORTH. CONVECTION TO THE SOUTH OF US WILL LIKELY DIE OUT THIS MORNING LEAVING OFBS. THROUGH DIFFERENTIAL HEATING...THIS AREA SHOULD BE WHERE THE BOUNDARY SHOULD EXIST. A LOW PRESSURE....MOVING OUT OF SOUTH DAKOTA WILL FORCE THIS BOUNDARY NORTH OVERNIGHT. WE WILL RESIDE WELL INTO THE WARM SECTOR. HIRES MESO MODELS...SUGGEST LITTLE TO NO STORM COVERAGE OVERNIGHT TONIGHT. WENT WITH SCATTERED POPS...BUT DO BELIEVE IT MAY BE VERY ISOLATED OR NON-EXISTENT...JUST DO NOT HAVE THE CONFIDENCE TO GO THAT WAY YET. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 327 AM CDT SUN JUN 21 2015 SEASONABLY WARM WITH POTENTIALLY SIGNIFICANT RAINS MID WEEK AND THEN TURNING COOLER. LONG TERM FORECAST CONFIDENCE ASSESSMENT...FAIR OR AVERAGE OVERALL EXCEPT POOR WED/THU WITH WAVE AND TIMING AND PLACEMENT OF HEAVY RAINS DUE TO POOR PHYSICS ISSUES OF ALL SOLUTIONS. CONCEPTUAL TRENDS SUGGEST HEAVIEST PRECIPITATION WOULD TEND TO BE FURTHER SOUTH THAN MOST SOLUTIONS. OVERVIEW...INITIALIZATION AND VERIFICATION GOOD WITH AGAIN DISPLACED SOUTHWARD CONVECTION FROM SOLUTIONS NOTED THAT SUPPORTS THIS AS AN ONGOING CONCERN FOR MID WEEK DUE TO BL MOISTURE IMBALANCES AS IS COMMON. RUN TO RUN CONTINUITY SUPPORTS A 70/30 MIX OF GFS TO HI-RES ECMWF ON FORCING AND THEN TRY AND APPLY ECMWF RAIN PACKAGE. MONDAY AND MONDAY NIGHT...VERY WARM...BREEZY AND HUMID WITH HIGHS MOSTLY 85 TO 90 SUGGESTED WITH A CONCERN NORTH SECTIONS MAY BE COOLER FROM MCS NEAR OR JUST NORTH OF HIGHWAY 20 FOR LATER SHIFTS TO MONITOR SINCE TENDENCY IS FOR GUIDANCE SOLUTIONS TO DISPLACE RAINS TOO FAR NORTH. POPS IN NORTH MAY BE A BIT TOO LOW WITH POPS SOUTH OF I-80 MAY BE TOO HIGH BASED ON JET AXIS AND 850 PARAMETERS. TUESDAY AND TUESDAY NIGHT...WEAK HIGH PRESSURE TO RESULT IN A FAIR DAY AND MOSTLY DRY TO DRY AND LOWERED HIGH TEMPERATURES AND DEWPOINTS. LATER SHIFTS MAY NEED TO LOWER DEWPOINTS FURTHER IN NORTH SECTIONS. TUESDAY NIGHT...REGION FAVORED TO EXPERIENCE LATE AN MCS WITH HEAVIEST RAINS ALONG AND SOUTH OF HIGHWAY 34. POPS MAY NEED RAISING WHEN TIMING ISSUES ARE BETTER RESOLVED WITH 1+ INCH AMOUNTS SUGGESTED AND LOW TO MARGINAL RISK OF SEVERE. WEDNESDAY...LOTS OF CLOUDS AND PRECIPITATION WITH HEAVIEST PRECIPITATION TO BE ALONG AND ESPECIALLY SOUTH OF I-80. FORCING AND MOISTURE PROFILES FAVOR WIDESPREAD .5 TO 1.5+ AMOUNTS WITH LOCALLY 2 TO 3 INCHES THAT COMBINED WITH TUESDAY NIGHT EVENT COULD RESULT IN RENEWED HYDRO ISSUES. SEVERE RISK APPEARS WILL BE ALONG AND MAYBE SOUTH OF IA/MO BORDER. HIGH TEMPERATURES BASED ON THIS PATTERN MAY NEED LOWERING BY LATER SHIFTS BY UP TO 5 DEGREES. LOWS ALSO WITH EVAPORATIVE COOLING MAY NEED LOWERING. THURSDAY THROUGH SATURDAY...BECOMING COOLER AND LESS HUMID AND MOSTLY DRY TO DRY AS NORTHWEST FLOW PATTERN DEVELOPS. HIGHS MID 70S TO LOWER 80S AND MINS UPPER 50S TO LOWER 60S WITH MODERATE HUMIDITY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 605 AM CDT SUN JUN 21 2015 LIFR AND IFR CONDITIONS TO CONTINUE FOR THE NEXT COUPLE OF HOURS AT THE TAF SITES. WITH THE SUN RISING...EXPECT THESE ISSUES TO GO AWAY. AFTER THIS SITES SHOULD VFR THROUGH THE PERIOD. WINDS WILL BE LIGHT AND VARIABLE THEN SHIFT TO THE SOUTH NEAR MID EVENING. THERE IS A SLIGHT CHANCE FOR THUNDER TONIGHT...HOWEVER LOW CONFIDENCE PRECLUDES ANY MENTION IN THE TAF. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR BENTON- BUCHANAN-CEDAR-CLINTON-DELAWARE-DUBUQUE-IOWA-JACKSON- JEFFERSON-JOHNSON-JONES-KEOKUK-LINN-VAN BUREN-WASHINGTON. IL...DENSE FOG ADVISORY UNTIL 9 AM CDT THIS MORNING FOR CARROLL-JO DAVIESS-STEPHENSON. MO...NONE. && $$ UPDATE...GIBBS SYNOPSIS...GIBBS SHORT TERM...GIBBS LONG TERM...NICHOLS AVIATION...GIBBS
AREA FORECAST DISCUSSION
NWS DES MOINES IA
1151 PM CDT SAT JUN 20 2015 .UPDATE... ISSUED AT 645 PM CDT SAT JUN 20 2015 COLD FRONT MAKING RAPID PROGRESS TO THE SOUTHEAST WITH THE AIRMASS BECOMING MORE STABLE BEHIND THE FRONT. EXPECT THE STORMS TO TRANSITION TO A BIG WIND THREAT AS THEY PUSH TO THE SOUTHEAST BUT FOR CENTRAL IOWA...STORMS SHOULD EXIT THE REGION BY 02Z WITH CLEARING SKIES ACROSS THE EAST BY 03Z. THE REMAINDER OF TONIGHT WILL BE QUIET. && .SHORT TERM /TONIGHT/... ISSUED AT 224 PM CDT SAT JUN 20 2015 FORECAST PROBLEM FOR TONIGHT WILL BE THUNDERSTORM DEVELOPMENT ALONG A FRONTAL BOUNDARY MAKING ITS WAY ACROSS CENTRAL IOWA. AT 20Z THE FRONTAL BOUNDARY WAS LOCATED ROUGHLY FROM OMAHA TO ATLANTIC THEN NORTHEAST TO FORT DODGE TO FOREST CITY. THE MAIN AREA OF CONCERN WILL BE THE I-80 CORRIDOR AND ESPECIALLY SOUTH WHERE IT HAS BEEN SUNNY ALL DAY AND HAS BEEN ABLE TO REALLY DESTABILIZE. MESOANALYSIS SHOWS AN UNCAPPED ENVIRONMENT WITH 5000-6000 CAPES ACROSS THE AREAS WEST OF I-35 AND SOUTH OF I-80. ONCE THE FRONT PUSHES TO THIS AREA THUNDERSTORMS SHOULD RAPIDLY DEVELOP AND BECOME SEVERE. AT THIS TIME IT LOOKS LIKE THE DES MOINES METRO AREA WILL BE ON THE WESTERN FRINGE OF THE DEVELOPMENT SO BETWEEN 21Z AND 00Z WE SHOULD SEE STORMS BLOW UP. STRONG LOW LEVEL SHEAR IN THE VICINITY OF THE FRONT WILL ALLOW FOR ROBUST UPDRAFTS AND THE POTENTIAL FOR A FEW TORNADOES. LARGE HAIL WILL ALSO BE A THREAT. THE STORMS WILL EVENTUALLY EVOLVE INTO A WIND THREAT AS WELL BUT THAT MAY BE EAST/SOUTH OF OUR AREA. THE STORMS SHOULD BE EAST OF THE AREA BY 06Z HOWEVER THE HRRR IS INDICATING A SECONDARY LINE DEVELOPING ALONG THE 850 FRONT AND PUSHING SOUTH BEFORE STALLING NEAR THE IA/MO BORDER. IF THIS HAPPENS SOUTHERN IOWA WILL BE GETTING SOME HEAVY RAINFALL AMOUNTS. AT THIS TIME CONFIDENCE IS LOW ON THAT SECOND SHOT OF RAINFALL SO I HAVE GRIDS CLEARING AFTER 06Z. .LONG TERM /SUNDAY THROUGH SATURDAY/... ISSUED AT 224 PM CDT SAT JUN 20 2015 SURFACE HIGH PRESSURE WILL BUILD ACROSS THE MIDWEST INTO THE OHIO VALLEY ON SUNDAY. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO BE SOUTH OF IOWA IN THE MORNING. A SHORTWAVE MOVING THROUGH THE WESTERLY FLOW ALOFT ACROSS THE NORTHERN PLAINS WILL STRENGTHEN A SURFACE LOW IN THE DAKOTAS SUNDAY AFTERNOON. THE PRESSURE GRADIENT IS EXPECTED TO TIGHTEN WITH SOUTHERLY SURFACE FLOW LIFTING A WARM FRONT NORTH. SHOWERS AND THUNDERSTORMS ARE EXPECTED TO DEVELOP NEAR THE FRONT LATE IN THE DAY WITH CONVECTION BECOMING MORE WIDESPREAD DURING THE EVENING AND OVERNIGHT HOURS. INSTABILITY AND DEEP LAYER SHEAR WILL BE SUFFICIENT FOR A FEW STRONG TO SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND HAIL THE PRIMARY HAZARDS. PRECIPITATION WILL END FROM SOUTHWEST TO NORTHEAST MONDAY. WARM FRONT LOOKS TO SETUP ACROSS NORTHERN KANSAS AND MISSOURI ON TUESDAY...GRADUALLY LIFTING NORTH AND PROVIDING A FOCUS FOR ADDITIONAL SHOWERS AND THUNDERSTORMS. THE LATE AFTERNOON THROUGH THE OVERNIGHT HOURS IS THE MOST LIKELY TIMEFRAME FOR PRECIPITATION. ANOTHER SHORTWAVE TROUGH MOVES THROUGH THE NORTHERN PLAINS INTO THE MIDWEST ON WEDNESDAY. OCCASIONAL SHOWERS AND THUNDERSTORMS COULD FESTER THROUGH THE DAY AIDED BY MULTIPLE SHORTWAVES MOVING THROUGH THE UPPER FLOW AND NEARBY FRONTAL BOUNDARY. PATTERN LOOKS TO REMAIN ACTIVE THROUGH THE END OF THE WEEK INTO NEXT WEEKEND WITH WEST AND NORTHWEST UPPER FLOW...MULTIPLE OUTFLOW BOUNDARIES AND A SURFACE FRONT SUPPORTING CHANCES FOR THUNDERSTORMS. && .AVIATION...21/06Z ISSUED AT 1151 PM CDT SAT JUN 20 2015 THUNDERSTORMS ARE EXPECTED TO REMAIN SOUTH OF THE SITES OVERNIGHT WITH WINDS BECOMING LIGHT AND VARIABLE AND CIGS REMAINING VFR. SOME POTENTIAL FOR FOG TO DEVELOP OVERNIGHT WILL HAVE TO MONITOR SITES THAT HAD AN ABUNDANCE OF RAIN THIS EVENING FOR DEVELOPMENT. VFR CONDITIONS ARE FORECAST ON SUNDAY WITH WINDS BECOMING SOUTHERLY. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...FAB SHORT TERM...FAB LONG TERM...ANGLE AVIATION...DONAVON
AREA FORECAST DISCUSSION
NWS GOODLAND KS
529 PM MDT MON JUN 22 2015 .SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY) ISSUED AT 222 PM MDT MON JUN 22 2015 WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD 597DM RIDGE IN PLACE ACROSS THE SOUTHER PLAINS WITH ZONAL FLOW ACROSS THE NORTHERN US. NORTHERN JET STREAM IS ACROSS THE NORTHERN PLAINS...WITH POSITIVELY TILTED TROUGH OVER NORTHERN MINNESOTA. THERE IS A WEAK SHORTWAVE OVER NORTH CENTRAL COLORADO WITH MINOR HEIGHT FALLS. THIS AFTERNOON-EVENING...VERY HIGH CINH/CAP WILL BE IN PLACE THIS AFTERNOON AND EVENING. FRONT IS NOW ALONG THE SOUTHERN EDGE OF CWA...WITH PRIMARY CONVERGENCE ALONG PRE FRONTAL TROUGH IN SW KANSAS. AT THIS POINT IT SEEMS UNLIKELY THE CAP WILL WEAKEN OR BREAK THIS AFTERNOON OR EARLY THIS EVENING...WITH ANY INITIATION LIMITED TO SW KANSAS OR HIGHER TERRAIN IN COLORADO. TONIGHT-TUESDAY MORNING...SHORTWAVE TROUGH OVERNIGHT COULD COMBINE WITH WEAK H85-H7 WAA ACROSS NE COLORADO TO PRODUCE A FEW ELEVATED THUNDERSTORMS NEAR STALLED FRONTAL ZONE. GUIDANCE IS SHOWING PRECIP SIGNAL IN THIS AREA SPREADING EASTWARD. MOISTURE PROFILES ARE UNIMPRESSIVE WITH LOW MIXING RATIOS/HIGH TD DEPRESSIONS THAT WOULD LIKELY LIMIT CONFIDENCE IN INITIATION OR COVERAGE. IF THUNDERSTORMS WERE TO DEVELOP MODERATE CAPE AND GOOD EFFECTIVE SHEER COULD SUPPORT SEVERE THUNDERSTORM DEVELOPMENT. I AM JUST NOT SURE IF WE ARE GOING TO SEE ANYTHING DEVELOP...SO I KEPT POPS LIMITED TO 20. GUIDANCE SHOWS GOOD BL MOISTURE ADVECTING WIT EASTERLY FLOW NORTH OF FRONT...POSSIBLY POOLING ALONG FRONTAL ZONE IN EASTERN COLORADO LATE TONIGHT/EARLY TUESDAY MORNING. I DECIDED TO KEEP OUT MENTION OF FOG WITH GUIDANCE KEEPING VISIBILITIES HIGH...HOWEVER THIS SHOULD BE MONITORED. TUESDAY...HI RES MODELS GENERALLY SHOW ANY THUNDERSTORM ACTIVITY TRANSITIONING EAST OF THE CWA BY MIDDAY TUESDAY WITH MEAN FLOW...AND I KEPT THIS TIMING IN PLACE. ANOTHER WEAK SHORTWAVE/RIPPLE WITHIN MEAN FLOW BEGINS TO APPROACH THE CWA FROM THE WEST TUESDAY AFTERNOON. FRONT WILL BE IN THE PROCESS OF LIFTING OVER THE CWA...SO WE COULD SEE INCREASING SURFACE CONVERGENCE THROUGH THE LATE AFTERNOON...WHICH COULD BE ENOUGH TO WEAKEN THE DAYTIME CAP. MODELS ARE SHOWING A FAIRLY LARGE SPREAD IN FRONT POSITION/TIMING...SO HIGH TEMPS AND THIS POTENTIAL FOR INITIATION IS UNCERTAIN. BEST MODEL CONSENSUS IS ON DEVELOPMENT BY LATE AFTERNOON IN THE SW...THOUGH THIS COULD STILL BE A LITTLE EARLY BASED ON MODEL TIMING OF BEST UPPER LEVEL FORCING/HEIGHT FALLS. WITH FRONTAL ZONE OVER CWA...THERE COULD BE BETTER SHEER PROFILES WITH VEERING ALONG FRONTAL ZONE AND ESPECIALLY IN THE WEST NEAR SURFACE TROUGH. RESULT COULD BE A BETTER CHANCE FOR SUPERCELL DEVELOPMENT IF THUNDERSTORMS DO DEVELOP. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 324 PM MDT MON JUN 22 2015 FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH THURSDAY AND HOW HOT DOES IT GET. SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST OF THE SOUTHERN HALF OF THE COUNTRY. AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE REMAINING OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE NAM. THE GFS...CANADIAN... AND THE ECMWF WERE DOING THE BEST ON THE LOW LEVEL THERMAL FIELD. TUESDAY NIGHT...MAIN JET WELL NORTH. POSSIBLY A WEAK REAR QUADRANT THAT MOVES ACROSS NEAR OR JUST NORTH OF OUR AREA. SURFACE TROUGH RESIDES OVER THE FAR WESTERN PORTION OF THE AREA LATE IN THE AFTERNOON/EARLY EVENING. AT THE SAME TIME A SHORTWAVE TROUGH WILL BEGIN AFFECTING THE FAR WEST LATE IN THE DAY AND THEN MOVE ACROSS THE AREA THROUGH THE REMAINDER OF THE NIGHT. PROBLEM IN THE BEGINNING COULD BE IF THE CAP IS TOO STRONG PLUS THE MODELS DIFFER ON HOW STRONG THE MID LIFT WILL BE. MODEL QPF IS NOT OVERLY IMPRESSIVE BUT IT DOES LOOK LIKE WE SHOULD BE GETTING MORE THAN WHAT IS CURRENTLY SHOWN. CHOSE TO PLAY IT CONSERVATIVELY AND ONLY GO SLIGHT CHANCE AT THIS TIME. WEDNESDAY/WEDNESDAY NIGHT...A LOT OF MODEL DIFFERENCES START SHOWING UP. A WEAKER RIGHT REAR QUADRANT STARTS AFFECTING THE NORTHERN THIRD TO HALF OF THE AREA DURING THE AFTERNOON INTO AT LEAST THE EVENING AND POSSIBLY INTO THE OVERNIGHT HOURS DEPENDING ON WHICH MODEL YOU CHOOSE. A SHORTWAVE TROUGH AND ITS SURFACE REFLECTION MOVE INTO THE NORTHWEST OF THE AREA BY 18Z AND THEN PROGRESS IT SOUTH AND EAST THROUGH THE AREA. PROBLEM IS IN HOW AGGRESSIVE THEY ARE IN MOVING THE FRONT THROUGH. THE NAM IS THE FASTEST WITH THE GFS MUCH SLOWER AND ONLY ABOUT HALF WAY THROUGH THE AREA BY LATE IN THE DAY. THE ECMWF IS SLIGHTLY SLOWER THAN THE NAM. AT THE SAME TIME THE MID LEVEL TEMPERATURES ARE NEAR PLUS 15. SO WHERE WILL THE SURFACE FOCUS BE AND IF THE CAP WILL BREAK. ALSO THE STRENGTH OF THE MID LIFT IS IN QUESTION. AGAIN DUE TO A LOT OF MODEL DIFFERENCE ON TIMING AND STRENGTH OF FEATURES...NOT A LOT OF CONFIDENCE IN WHAT WILL HAPPEN. SO ONCE AGAIN CHOSE ONLY TO GO SLIGHT CHANCE BUT IF BETTER MODEL AGREEMENT WOULD HAPPEN WOULD FEEL A HIGHER CHANCE IS DESERVED. DUE TO THE BIG MODEL DIFFERENCES IN WHERE THE BOUNDARY...THERE IS A HUGE DIFFERENCE IN HOW WARM THEY MAKE IT. CHOSE TO GO IN THE MIDDLE AND CLOSER TO THE OUTPUT THAT HAS BEEN DOING BETTER RECENTLY. THURSDAY...DIFFERENCE IN FRONTAL POSITION CONTINUE. MAJORITY OF THE OUTPUT WOULD SUPPORT THE FRONT BEING A LITTLE FURTHER SOUTH OF THE FORECAST AREA. SO FELT BETTER ABOUT GOING COOLER. PROXIMITY OF THE BOUNDARY AND MID LEVEL LIFT ROUGHLY ALONG THE SOUTHERN AND WESTERN HOURS SUPPORT HAVING THE AFTERNOON POPS IN THE SOUTH AND WEST BUT NOT VERY CONFIDENT. THURSDAY NIGHT THROUGH MONDAY...MODELS START THE AMPLIFICATION PROCESS TO A STRONG WESTERN RIDGE AND EASTERN CONUS TROUGH. FLOW BECOMES SHIFTS MORE TOWARD THE NORTH BY THE END OF THE PERIOD. MODELS HAVING A LOT OF DIFFERENCE IN HOW THEY HANDLE THE POSITION OF WHERE THE SURFACE BOUNDARY ENDS UP. MORE THAN LIKELY WILL INITIALLY HAVE THE FRONT STAY OR START JUST TO THE SOUTH OF THE FORECAST AREA AND THEN WILL HAVE ADDITIONAL COLD INTRUSIONS. DID NOT MAKE ANY CHANGES TO WHAT THE CRH_INIT GRIDS GAVE ME DUE TO THE INITIAL UNCERTAIN ABOUT THE SURFACE FEATURES. THE MOST ACTIVE AND WET PART OF THE PERIOD WILL BE THURSDAY NIGHT INTO SATURDAY NIGHT. AFTER THAT IT BECOMES DRIER AS THE RIDGE EXERTS ITS INFLUENCE ALONG WITH THE DRIER NORTHERLY FLOW. ONLY ISOLATED PRECIPITATION IS EXPECTED FROM SUNDAY INTO MONDAY. TEMPERATURES WILL NOT WARM UP TOO MUCH DUE TO THE NORTHERLY FLOW. MAY BE POSSIBLE THAT TEMPERATURES MAY NEED TO BE LOWERED A LITTLE AS WE GET CLOSER TO THIS PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 525 PM MDT MON JUN 22 2015 VFR CONDITIONS ARE EXPECTED AT KGLD AND KMCK TONIGHT AND TUESDAY. SOME INCREASING BOUNDARY LAYER RH MAY BRING STRATUS INTO KGLD AND KMCK AS HIGH PRESSURE AND EASTERLY WINDS PRODUCES FAVORABLE UPSLOPE CONDITIONS. ANY STRATUS SHOULD BREAK UP QUICKLY TUESDAY MORNING. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BULLER AVIATION...FS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
323 PM CDT SUN JUN 21 2015 ...UPDATED FOR LONG TERM DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 231 PM CDT SUN JUN 21 2015 THIS MORNINGS UPPER AIR ANALYSIS SHOWED AN UPPER LEVEL RIDGE CONTINUING TO STRETCH FROM A HIGH CENTERED NEAR THE FOUR CORNERS REGION EASTWARD ALONG THE KANSAS/OKLAHOMA BORDER INTO THE SOUTHEASTERN STATES. THE STRONGEST UPPER LEVEL WESTERLY FLOW CONTINUES TO BE LOCATED ACROSS THE NORTHERN CONUS. TWO SHORTWAVE TROUGHS IN THE WESTERLY FLOW WERE LOCATED OVER SOUTHERN PORTIONS OF BRITISH COLUMBIA AND ALBERTA AS WELL AS OVER THE WEST COAST OF OREGON AND FAR NORTHERN CALIFORNIA. ACROSS THE CENTRAL PLAINS, AN OUTFLOW BOUNDARY THAT WAS DRIVEN SOUTH INTO WESTERN KANSAS THIS MORNING WAS LIFTING BACK NORTHWARD THIS AFTERNOON AS SOUTHERLY WINDS WERE RETURNING TO ALL THE OBSERVATION SITES IN WESTERN AND CENTRAL KANSAS. OVER THE NEXT 24-36 HOURS, THE UPPER LEVEL HIGH OVER THE SOUTHWEST WILL SLOWLY PROPAGATE EAST INTO THE CENTRAL/SOUTHERN PLAINS. THE DISTURBANCES OVER THE PACIFIC NORTHWEST ARE PROGGED TO COME INTO PHASE AND TRACK EAST ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY MONDAY EVENING. EXPECTING ANOTHER QUIET PERIOD THIS EVENING AND OVERNIGHT. MOST MODEL SOLUTIONS DO NOT GENERATE ANY PRECIPITATION ACROSS WESTERN KANSAS THIS EVENING ALTHOUGH THE RAP AND ESPECIALLY THE HRRR DEVELOP THUNDERSTORMS ALONG AND SOUTH OF I-70 IN CENTRAL KANSAS LATE THIS AFTERNOON AND EVENING. MODEL SOUNDINGS SHOW A NICE CAPPING INVERSION AROUND 700 MILLIBARS WHICH SHOULD EFFECTIVELY KEEP A LID ON ANY CONVECTIVE DEVELOPMENT. WHILE I COULDN`T TOTALLY RULE OUT AN ISOLATED THUNDERSTORM SIMILAR TO SATURDAY EVENING, WILL LEAVE THE FORECAST DRY FOR NOW. SOUTHERLY WINDS WILL CONTINUE AROUND 10-20 MPH OVERNIGHT WHICH SHOULD HOLD OVERNIGHT LOWS UP A FEW MORE DEGREES THAN LAST NIGHT. ON MONDAY, A WEAK COLD FRONT WILL PUSH SOUTHWARD INTO WEST CENTRAL KANSAS BY MIDDAY OR EARLY AFTERNOON. THIS COULD HOLD TEMPERATURES BACK A FEW DEGREES AND HAVE LOWERED HIGHS A FEW DEGREES FROM HAYS THROUGH SYRACUSE MONDAY AFTERNOON. FARTHER SOUTH OVER THE REMAINDER OF SOUTHWEST KANSAS, WE SHOULD SEE HIGHS BACK UP TO AROUND 100 DEGREES. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 307 PM CDT SUN JUN 21 2015 UPPER LEVEL RIDGING OVER THE SOUTHERN PLAINS THROUGH MIDWEEK WILL SHIFT WESTWARD INTO THE ROCKIES BY THURSDAY AND THROUGH THE WEEKEND WHILE GRADUALLY AMPLIFYING. THIS WILL GENERALLY BE A HOT PATTERN THROUGH THURSDAY OR FRIDAY, WITH SMALL CHANCES FOR THUNDERSTORMS NEAR A FRONTAL ZONE ACROSS WEST CENTRAL KANSAS AND NEAR INTERSTATE 70. GIVEN THE WEAK WINDS AT UPPER LEVELS, THESE STORMS WILL PROBABLY NOT BE SEVERE, WITH ONLY AN ISOLATED DAMAGING WIND GUST AND SMALL HAIL. HIGH TEMPERATURES WILL MAINLY BE IN THE MID TO UPPER 90S THROUGH FRIDAY, WITH LOWS GENERALLY IN THE UPPER 60S TO LOWER 70S. TEMPERATURES COULD BE SLIGHT COOLER ALONG INTERSTATE 70 DEPENDING ON THE EXACT LOCATION OF THE FRONTAL BOUNDARY AND ANY POSSIBLE THUNDERSTORM CLUSTERS PRODUCING COOL OUTFLOW. AS THE UPPER LEVEL RIDGE RETROGRADES BACK OVER THE WEST AND AMPLIFIES BY THE WEEKEND, HIGH TEMPERATURES WILL DROP BACK INTO THE MID 80S TO LOWER 90S STARTING SATURDAY, ALONG WITH A FEW THUNDERSTORMS AS THE COLD FRONT PASSES FROM THURSDAY NIGHT THROUGH FRIDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1201 PM CDT SUN JUN 21 2015 AN OUTFLOW BOUNDARY FROM EARLY MORNING THUNDERSTORMS OVER NEBRASKA AND FAR NORTHERN KANSAS WILL BE SITUATED IN THE HAYS AND GARDEN CITY AREAS THROUGH A GOOD PART OF THE AFTERNOON BEFORE WASHING OUT AND LIFTING BACK NORTH. WINDS AT THESE LOCATIONS WILL BE VARIABLE AT AROUND 10 KNOTS OR SO THIS AFTERNOON WITH ALL LOCATIONS BECOMING SOUTHERLY AT 10 TO 15 KNOTS SUSTAINED BY 00Z. VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 100 70 97 / 0 10 10 0 GCK 71 99 69 98 / 0 10 20 0 EHA 70 101 70 97 / 0 10 20 0 LBL 70 101 70 97 / 0 10 10 0 HYS 73 97 70 93 / 0 10 20 10 P28 74 99 72 96 / 0 10 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GERARD LONG TERM...FINCH AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
232 PM CDT SUN JUN 21 2015 ...UPDATED SHORT TERM DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 231 PM CDT SUN JUN 21 2015 THIS MORNINGS UPPER AIR ANALYSIS SHOWED AN UPPER LEVEL RIDGE CONTINUING TO STRETCH FROM A HIGH CENTERED NEAR THE FOUR CORNERS REGION EASTWARD ALONG THE KANSAS/OKLAHOMA BORDER INTO THE SOUTHEASTERN STATES. THE STRONGEST UPPER LEVEL WESTERLY FLOW CONTINUES TO BE LOCATED ACROSS THE NORTHERN CONUS. TWO SHORTWAVE TROUGHS IN THE WESTERLY FLOW WERE LOCATED OVER SOUTHERN PORTIONS OF BRITISH COLUMBIA AND ALBERTA AS WELL AS OVER THE WEST COAST OF OREGON AND FAR NORTHERN CALIFORNIA. ACROSS THE CENTRAL PLAINS, AN OUTFLOW BOUNDARY THAT WAS DRIVEN SOUTH INTO WESTERN KANSAS THIS MORNING WAS LIFTING BACK NORTHWARD THIS AFTERNOON AS SOUTHERLY WINDS WERE RETURNING TO ALL THE OBSERVATION SITES IN WESTERN AND CENTRAL KANSAS. OVER THE NEXT 24-36 HOURS, THE UPPER LEVEL HIGH OVER THE SOUTHWEST WILL SLOWLY PROPAGATE EAST INTO THE CENTRAL/SOUTHERN PLAINS. THE DISTURBANCES OVER THE PACIFIC NORTHWEST ARE PROGGED TO COME INTO PHASE AND TRACK EAST ACROSS THE NORTHERN PLAINS INTO THE WESTERN GREAT LAKES BY MONDAY EVENING. EXPECTING ANOTHER QUIET PERIOD THIS EVENING AND OVERNIGHT. MOST MODEL SOLUTIONS DO NOT GENERATE ANY PRECIPITATION ACROSS WESTERN KANSAS THIS EVENING ALTHOUGH THE RAP AND ESPECIALLY THE HRRR DEVELOP THUNDERSTORMS ALONG AND SOUTH OF I-70 IN CENTRAL KANSAS LATE THIS AFTERNOON AND EVENING. MODEL SOUNDINGS SHOW A NICE CAPPING INVERSION AROUND 700 MILLIBARS WHICH SHOULD EFFECTIVELY KEEP A LID ON ANY CONVECTIVE DEVELOPMENT. WHILE I COULDN`T TOTALLY RULE OUT AN ISOLATED THUNDERSTORM SIMILAR TO SATURDAY EVENING, WILL LEAVE THE FORECAST DRY FOR NOW. SOUTHERLY WINDS WILL CONTINUE AROUND 10-20 MPH OVERNIGHT WHICH SHOULD HOLD OVERNIGHT LOWS UP A FEW MORE DEGREES THAN LAST NIGHT. ON MONDAY, A WEAK COLD FRONT WILL PUSH SOUTHWARD INTO WEST CENTRAL KANSAS BY MIDDAY OR EARLY AFTERNOON. THIS COULD HOLD TEMPERATURES BACK A FEW DEGREES AND HAVE LOWERED HIGHS A FEW DEGREES FROM HAYS THROUGH SYRACUSE MONDAY AFTERNOON. FARTHER SOUTH OVER THE REMAINDER OF SOUTHWEST KANSAS, WE SHOULD SEE HIGHS BACK UP TO AROUND 100 DEGREES. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 356 AM CDT SUN JUN 21 2015 THE OVERALL SENSIBLE WEATHER WILL BE INFLUENCED MAINLY BY THE WARM AIRMASS AND FLAT HOT UPPER RIDGE EXTENDING ACROSS THE SOUTHERN ROCKIES THROUGH THE CENTRAL AND SOUTHERN PLAINS REGION. 700 MB TEMPERATURES RANGE FROM AROUND +14 TO IN EXCESS OF +17 DEGREES DURING THIS TIMEFRAME. A LEE SURFACE IS MODELED BY THE GFS/ECMWF ON TUESDAY EVENING, WITH SOME POSSIBILITY OF WEAK FORCED CONVECTION DEVELOPING IN THE CONVERGENCE ZONE AREA, AND POSSIBLY EXTENDING NORTHWARD ALONG A WARM FRONT MOST LIKELY NORTH OF SOUTHWEST AND CENTRAL KANSAS. HOWEVER, ANY DEVELOPMENT WILL BE FIGHTING A STRONG CAP, AND ADDITIONALLY WITH WEAK FLOW SEVERE WEATHER DOESN`T APPEAR PROBABLE. BETTER CHANCES ARE FORECAST BY TUESDAY NIGHT INTO WEDNESDAY TIMEFRAME AS HIGH TERRAIN STORMS MAY BEGIN TO HAVE A BETTER CHANCE TO BE DRIVEN EASTWARD INTO THE PLAINS WITH COMPACT SHORTWAVES ON THE BACKSIDE OF THE EXITING UPPER HIGH. TEMPERATURES REMAIN IN THE MID TO UPPER 90S FOR HIGH TEMPERATURES THROUGH THE WEEK, HOWEVER THE MODELS AND MOS BEGIN TO INDICATE SOME RELIEF BY THE WEEKEND AS THE UPPER RIDGING SHIFTS INTO THE SOUTHEAST US. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1201 PM CDT SUN JUN 21 2015 AN OUTFLOW BOUNDARY FROM EARLY MORNING THUNDERSTORMS OVER NEBRASKA AND FAR NORTHERN KANSAS WILL BE SITUATED IN THE HAYS AND GARDEN CITY AREAS THROUGH A GOOD PART OF THE AFTERNOON BEFORE WASHING OUT AND LIFTING BACK NORTH. WINDS AT THESE LOCATIONS WILL BE VARIABLE AT AROUND 10 KNOTS OR SO THIS AFTERNOON WITH ALL LOCATIONS BECOMING SOUTHERLY AT 10 TO 15 KNOTS SUSTAINED BY 00Z. VFR CONDITIONS SHOULD PREVAIL THROUGH THE PERIOD. && .PRELIMINARY POINT TEMPS/POPS... DDC 72 100 70 96 / 0 10 10 0 GCK 71 99 69 97 / 0 10 20 0 EHA 70 101 70 97 / 0 10 20 0 LBL 70 101 70 95 / 0 10 10 0 HYS 73 97 70 93 / 0 10 20 10 P28 74 99 72 96 / 0 10 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GERARD LONG TERM...RUSSELL AVIATION...GERARD
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1145 AM MDT SUN JUN 21 2015 .UPDATE... ISSUED AT 810 AM MDT SUN JUN 21 2015 JUST COMPLETED AN UPDATE. THIS WAS DONE MAINLY TO ADD THUNDERSTORMS TO THIS MORNING FOR THE NORTHEAST PORTION OF THE AREA DUE TO THE THUNDERSTORM COMPLEX MOVING OUT OF CENTRAL NEBRASKA. THIS COMPLEX HAS THROWN OUT AN OUTFLOW BOUNDARY AND HAS CAUSED ADDITIONAL CLOUD COVER TO DEVELOP. THE RUC HAS CAUGHT THIS GENERAL SCENARIO WELL WHICH KEEPS NORTHERLY WINDS AROUND INTO THE AFTERNOON. SO IN ADDITION TO THE PRECIPITATION INCREASED CLOUD COVER AND CHANGED THE WIND FIELD. DID LOWER THE TEMPERATURES A LITTLE ESPECIALLY IN THE NORTHEAST. HOWEVER AFTER THIS COMPLEX GOES PASSED...RUC DOES WANT TO SHIFT THE WINDS BACK TO A SOUTHERLY DIRECTION AND STILL BRING IN HOT TEMPERATURES. NOT SURE ABOUT THAT AND WILL WAIT/WATCH TO SEE WHAT HAPPENS THIS MORNING BEFORE MAKING FURTHER IF ANY ADJUSTMENTS. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 330 AM MDT SUN JUN 21 2015 TODAY-TONIGHT...FORECAST CONCERN IS THE HEAT. STATIONARY FRONT CURRENTLY TO THE SOUTH OF THE FORECAST AREA THIS MORNING WITH MUCH OF THE AREA UNDER EAST/NORTHEAST WINDS. NAM/RUC BOUNDARY LAYER RH INCREASE SIGNIFICANTLY ALONG/NORTH OF THE FRONT RESULTING IN AREAS OF FOG THROUGH MID MORNING. DURING THE AFTERNOON HOURS FRONT SLOWLY LIFTS NORTH WITH INCREASING SOUTHERLY WINDS BEHIND IT. A GENERALLY SUNNY SKY EXPECTED WITH AFTERNOON TEMPERATURES IN THE MID 90S TO AROUND 100 ALONG/NORTH OF THE INTERSTATE WITH UPPER 90S TO AROUND 103 SOUTH. LUCKILY NOT EXPECTING FULL MIXING AT 850MB WHICH BASED ON THE PAST 5 DAYS WOULD SUPPORT READINGS ABOUT 4F HIGHER AND PRODUCE SOME NEAR RECORD HIGHS. FOR TONIGHT WARM FRONT CONTINUES NORTH WITH BREEZY TO WINDY SOUTH WINDS THROUGH MIDNIGHT BEFORE VEERING TO THE SOUTHWEST LATE AHEAD OF AN APPROACHING FRONT. LOW TEMPERATURES IN THE LOW TO MID 60S IN FAR EASTERN COLORADO WITH MID 60S TO MID 70S EAST OF THE STATE LINE. HEAT INDEX VALUES MAY APPROACH 100 DEGREES IN THE HILL CITY AND GOVE AREAS...BELOW 105 THRESHOLD FOR HEAT ADVISORY. MONDAY-MONDAY NIGHT...BROAD 594-596DM HIGH PRESSURE CENTER EXTENDS FROM SOUTHERN KANSAS TO ARIZONA DURING THE DAY SLOWLY LIFTING NORTHWARD DURING THE NIGHT. NAM/GFS/SREF/ECMWF ALL SHOWING AN AREA OF INCREASING MID LEVEL MOISTURE LIFTING NORTHEAST INTO THE AREA DURING THE NIGHT...EXITING THE NORTHEAST CORNER OF THE AREA AROUND 12Z TUESDAY MORNING. NOSE OF MODEST LOW LEVEL JET FEEDING INTO THIS FEATURE AND ELEVATED CONVECTIVE INHIBITION LOW ENOUGH TO WARRANT A SLIGHT CHANCE AND LOW CHANCE OF THUNDERSTORMS. COLD FRONT MOVES THROUGH DURING THE DAY BRINGING SOME NORTH WINDS GUSTING TO 25 MPH OR SO IN THE MORNING WITH A SLOW DECREASE AND VEER TO THE NORTHEAST THEN EAST-NORTHEAST IN THE AFTERNOON. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER 80S TO LOW 90S FROM FLAGLER TO GOODLAND TO MCCOOK AND POINTS WEST WITH MID 90S TO AROUND 102 ELSEWHERE...HOTTEST FROM HILL CITY TO TRIBUNE WHERE HEAT BUILDS BEFORE THE FRONTS ARRIVAL. LOW TEMPERATURES IN THE LOW TO MID 60S...UPPER 60S CONFINED TO AREAS SOUTH OF A LINE FROM HILL CITY TO GOVE TO TRIBUNE. TUESDAY-TUESDAY NIGHT...MAY HAVE A FEW LINGERING THUNDERSTORMS IN THE MORNING FROM TRENTON/MCCOOK EAST THROUGH NORTON BEFORE EXITING THE AREA TO THE NORTHEAST BEFORE 18Z. FOR THE REST OF THE AFTERNOON WILL HAVE TO MONITOR NORTHWARD PROGRESSION OF FRONTAL BOUNDARY AS SHOWERS/THUNDERSTORMS POSSIBLE ALONG ITS LEADING EDGE WHERE LOW LEVEL CONVERGENCE...BETTER MOISTURE AND LIMITED CONVECTIVE INHIBITION EXIST. DURING THE EVENING AND EARLY OVERNIGHT HOURS ANY PRECIP THAT DOES DEVELOP SHOULD LIFT NORTH AND LIKELY OUT OF THE AREA EARLY WEDNESDAY MORNING. HIGH TEMPERATURES IN THE MID 80S ALONG THE KS/NE BORDER WITH UPPER 90S TO AROUND 100 FOR PARTS OF GOVE...GREELEY AND WICHITA COUNTIES. LOW TEMPERATURES IN THE LOW 60S WEST TO AROUND 70 EAST. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 227 AM MDT SUN JUN 21 2015 THE MAIN UPPER LEVEL JET FLOW WEDNESDAY WILL REMAIN NORTH OF THE TRI STATE AREA WITH A BROAD UPPER LEVEL HIGH PRESSURE SYSTEM PARKED OVER THE SOUTHERN PLAINS AND THE SOUTHEAST PORTIONS OF THE CONUS. WITH A LACK OF JET LEVEL FORCING...THE HIGH PRESSURE SYSTEM ACTUALLY WILL RETROGRADE TO THE WEST WEDNESDAY AND THURSDAY. THE UPPER FLOW PATTERN FRIDAY WILL BECOME MORE AMPLIFIED AS A RIDGE BUILDS OVER THE WESTERN THIRD OF THE CONUS WITH A TROUGH OVER THE EASTERN THIRD OF THE CONUS. ALTHOUGH THERE IS WEAK FORCING AT THE UPPER LEVELS...WEAK SHORTWAVE TROUGH DISTURBANCES WILL MOVE ACROSS THE ROCKIES AND INTO THE TRI STATE AREA WEDNESDAY AND THURSDAY. THESE DISTURBANCES WILL BRING CHANCES FOR PRODUCING SHOWERS AND THUNDERSTORMS FOR SOME PARTS OF THE AREA. THE CAP VIA GFS MODEL SOUNDINGS DOES NOT LOOK AS IMPRESSIVE COMPARED TO PREVIOUS RUNS...SO MID LEVEL FORCING MAY HELP INITIATE STORMS DESPITE LACK OF STRONG JET PRESENCE. GFS/ECMWF MODELS HAVE A SURFACE BOUNDARY POSITIONED AROUND THE TRI STATE AREA FOR BOTH WEDNESDAY AND THURSDAY WITH SURFACE DEW POINTS IN THE UPPER 50S TO LOWER 60S...SO SHOWERS AND THUNDERSTORMS WILL DEFINITELY BE POSSIBLE MAINLY EAST OF HIGHWAY 83 WHERE THE BOUNDARY SETS UP. THE LOCATION OF PRECIPITATION WILL BE SUBJECT TO CHANGE BASED ON WHERE EXACTLY THE SURFACE AND 850 MB BOUNDARY IS POSITIONED. CHANCES FOR PRECIPITATION WILL CONTINUE THURSDAY NIGHT INTO FRIDAY AS MOISTURE IS STREAMED INTO THE REGION FROM THE NORTHWEST IN COMBINATION WITH A WEAK SURFACE COOL FRONT THAT PUSHES INTO THE FORECAST AREA. HIGH TEMPERATURES WILL BE AFFECTED VERY LITTLE WITH DROPS OF ABOUT 5 DEGREES FROM THE LOWER 90S TO THE MID 80S. DISAGREEMENT IN MODEL PRECIPITATION OCCURS ON SATURDAY...WITH MOST MODELS STAYING DRY WITH ANOTHER FRONTAL PASSAGE. THE GFS MODEL IS THE ONLY FORECAST THAT IS AGGRESSIVELY BRINGING WIDESPREAD HEAVIER PRECIPITATION SATURDAY NIGHT INTO EARLY SUNDAY MORNING. THE GFS SOLUTION SEEMED TO HEAVILY AFFECT CONSENSUS FORECASTS DESPITE OTHER FORECASTS REMAINING DRY. LOWERED POPS A BIT...ESPECIALLY FOR SOUTHWEST CORNER OF THE FORECAST AREA TO REMAIN WITHIN COLLABORATIVE THRESHOLDS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1140 AM MDT SUN JUN 21 2015 VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. AS THE AFFECTS OF THIS MORNINGS CONVECTION ARE LESSENED AND AS A FRONT TO OUR SOUTH MOVES NORTH AS A WARM FRONT...WINDS WILL SHIFT TO SOUTH AND SOUTHEAST THIS AFTERNOON AND INCREASE AT BOTH SITES. THE WINDS WILL BE QUITE STRONG AND GUSTY DURING THE EVENING. SUSTAINED WINDS OF 16 TO 20 KNOTS WITH GUSTS NEARING 30 KNOTS ARE EXPECTED UNTIL 09Z TO 11Z WHEN THEY DECREASE AND BECOME MORE WESTERLY. A COLD FRONT WILL THEN MOVE THROUGH NEAR 14Z WITH A SHIFT TO THE NORTH AS WINDS GUST TO NEAR 25 KNOTS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...99 LONG TERM...MK AVIATION...BULLER
AREA FORECAST DISCUSSION
NWS GOODLAND KS
815 AM MDT SUN JUN 21 2015 .UPDATE... ISSUED AT 810 AM MDT SUN JUN 21 2015 JUST COMPLETED AN UPDATE. THIS WAS DONE MAINLY TO ADD THUNDERSTORMS TO THIS MORNING FOR THE NORTHEAST PORTION OF THE AREA DUE TO THE THUNDERSTORM COMPLEX MOVING OUT OF CENTRAL NEBRASKA. THIS COMPLEX HAS THROWN OUT AN OUTFLOW BOUNDARY AND HAS CAUSED ADDITIONAL CLOUD COVER TO DEVELOP. THE RUC HAS CAUGHT THIS GENERAL SCENARIO WELL WHICH KEEPS NORTHERLY WINDS AROUND INTO THE AFTERNOON. SO IN ADDITION TO THE PRECIPITATION INCREASED CLOUD COVER AND CHANGED THE WIND FIELD. DID LOWER THE TEMPERATURES A LITTLE ESPECIALLY IN THE NORTHEAST. HOWEVER AFTER THIS COMPLEX GOES PASSED...RUC DOES WANT TO SHIFT THE WINDS BACK TO A SOUTHERLY DIRECTION AND STILL BRING IN HOT TEMPERATURES. NOT SURE ABOUT THAT AND WILL WAIT/WATCH TO SEE WHAT HAPPENS THIS MORNING BEFORE MAKING FURTHER IF ANY ADJUSTMENTS. && .SHORT TERM...(TODAY THROUGH TUESDAY NIGHT) ISSUED AT 330 AM MDT SUN JUN 21 2015 TODAY-TONIGHT...FORECAST CONCERN IS THE HEAT. STATIONARY FRONT CURRENTLY TO THE SOUTH OF THE FORECAST AREA THIS MORNING WITH MUCH OF THE AREA UNDER EAST/NORTHEAST WINDS. NAM/RUC BOUNDARY LAYER RH INCREASE SIGNIFICANTLY ALONG/NORTH OF THE FRONT RESULTING IN AREAS OF FOG THROUGH MID MORNING. DURING THE AFTERNOON HOURS FRONT SLOWLY LIFTS NORTH WITH INCREASING SOUTHERLY WINDS BEHIND IT. A GENERALLY SUNNY SKY EXPECTED WITH AFTERNOON TEMPERATURES IN THE MID 90S TO AROUND 100 ALONG/NORTH OF THE INTERSTATE WITH UPPER 90S TO AROUND 103 SOUTH. LUCKILY NOT EXPECTING FULL MIXING AT 850MB WHICH BASED ON THE PAST 5 DAYS WOULD SUPPORT READINGS ABOUT 4F HIGHER AND PRODUCE SOME NEAR RECORD HIGHS. FOR TONIGHT WARM FRONT CONTINUES NORTH WITH BREEZY TO WINDY SOUTH WINDS THROUGH MIDNIGHT BEFORE VEERING TO THE SOUTHWEST LATE AHEAD OF AN APPROACHING FRONT. LOW TEMPERATURES IN THE LOW TO MID 60S IN FAR EASTERN COLORADO WITH MID 60S TO MID 70S EAST OF THE STATE LINE. HEAT INDEX VALUES MAY APPROACH 100 DEGREES IN THE HILL CITY AND GOVE AREAS...BELOW 105 THRESHOLD FOR HEAT ADVISORY. MONDAY-MONDAY NIGHT...BROAD 594-596DM HIGH PRESSURE CENTER EXTENDS FROM SOUTHERN KANSAS TO ARIZONA DURING THE DAY SLOWLY LIFTING NORTHWARD DURING THE NIGHT. NAM/GFS/SREF/ECMWF ALL SHOWING AN AREA OF INCREASING MID LEVEL MOISTURE LIFTING NORTHEAST INTO THE AREA DURING THE NIGHT...EXITING THE NORTHEAST CORNER OF THE AREA AROUND 12Z TUESDAY MORNING. NOSE OF MODEST LOW LEVEL JET FEEDING INTO THIS FEATURE AND ELEVATED CONVECTIVE INHIBITION LOW ENOUGH TO WARRANT A SLIGHT CHANCE AND LOW CHANCE OF THUNDERSTORMS. COLD FRONT MOVES THROUGH DURING THE DAY BRINGING SOME NORTH WINDS GUSTING TO 25 MPH OR SO IN THE MORNING WITH A SLOW DECREASE AND VEER TO THE NORTHEAST THEN EAST-NORTHEAST IN THE AFTERNOON. HIGH TEMPERATURES SHOULD RANGE FROM THE UPPER 80S TO LOW 90S FROM FLAGLER TO GOODLAND TO MCCOOK AND POINTS WEST WITH MID 90S TO AROUND 102 ELSEWHERE...HOTTEST FROM HILL CITY TO TRIBUNE WHERE HEAT BUILDS BEFORE THE FRONTS ARRIVAL. LOW TEMPERATURES IN THE LOW TO MID 60S...UPPER 60S CONFINED TO AREAS SOUTH OF A LINE FROM HILL CITY TO GOVE TO TRIBUNE. TUESDAY-TUESDAY NIGHT...MAY HAVE A FEW LINGERING THUNDERSTORMS IN THE MORNING FROM TRENTON/MCCOOK EAST THROUGH NORTON BEFORE EXITING THE AREA TO THE NORTHEAST BEFORE 18Z. FOR THE REST OF THE AFTERNOON WILL HAVE TO MONITOR NORTHWARD PROGRESSION OF FRONTAL BOUNDARY AS SHOWERS/THUNDERSTORMS POSSIBLE ALONG ITS LEADING EDGE WHERE LOW LEVEL CONVERGENCE...BETTER MOISTURE AND LIMITED CONVECTIVE INHIBITION EXIST. DURING THE EVENING AND EARLY OVERNIGHT HOURS ANY PRECIP THAT DOES DEVELOP SHOULD LIFT NORTH AND LIKELY OUT OF THE AREA EARLY WEDNESDAY MORNING. HIGH TEMPERATURES IN THE MID 80S ALONG THE KS/NE BORDER WITH UPPER 90S TO AROUND 100 FOR PARTS OF GOVE...GREELEY AND WICHITA COUNTIES. LOW TEMPERATURES IN THE LOW 60S WEST TO AROUND 70 EAST. .LONG TERM...(WEDNESDAY THROUGH SATURDAY) ISSUED AT 227 AM MDT SUN JUN 21 2015 THE MAIN UPPER LEVEL JET FLOW WEDNESDAY WILL REMAIN NORTH OF THE TRI STATE AREA WITH A BROAD UPPER LEVEL HIGH PRESSURE SYSTEM PARKED OVER THE SOUTHERN PLAINS AND THE SOUTHEAST PORTIONS OF THE CONUS. WITH A LACK OF JET LEVEL FORCING...THE HIGH PRESSURE SYSTEM ACTUALLY WILL RETROGRADE TO THE WEST WEDNESDAY AND THURSDAY. THE UPPER FLOW PATTERN FRIDAY WILL BECOME MORE AMPLIFIED AS A RIDGE BUILDS OVER THE WESTERN THIRD OF THE CONUS WITH A TROUGH OVER THE EASTERN THIRD OF THE CONUS. ALTHOUGH THERE IS WEAK FORCING AT THE UPPER LEVELS...WEAK SHORTWAVE TROUGH DISTURBANCES WILL MOVE ACROSS THE ROCKIES AND INTO THE TRI STATE AREA WEDNESDAY AND THURSDAY. THESE DISTURBANCES WILL BRING CHANCES FOR PRODUCING SHOWERS AND THUNDERSTORMS FOR SOME PARTS OF THE AREA. THE CAP VIA GFS MODEL SOUNDINGS DOES NOT LOOK AS IMPRESSIVE COMPARED TO PREVIOUS RUNS...SO MID LEVEL FORCING MAY HELP INITIATE STORMS DESPITE LACK OF STRONG JET PRESENCE. GFS/ECMWF MODELS HAVE A SURFACE BOUNDARY POSITIONED AROUND THE TRI STATE AREA FOR BOTH WEDNESDAY AND THURSDAY WITH SURFACE DEW POINTS IN THE UPPER 50S TO LOWER 60S...SO SHOWERS AND THUNDERSTORMS WILL DEFINITELY BE POSSIBLE MAINLY EAST OF HIGHWAY 83 WHERE THE BOUNDARY SETS UP. THE LOCATION OF PRECIPITATION WILL BE SUBJECT TO CHANGE BASED ON WHERE EXACTLY THE SURFACE AND 850 MB BOUNDARY IS POSITIONED. CHANCES FOR PRECIPITATION WILL CONTINUE THURSDAY NIGHT INTO FRIDAY AS MOISTURE IS STREAMED INTO THE REGION FROM THE NORTHWEST IN COMBINATION WITH A WEAK SURFACE COOL FRONT THAT PUSHES INTO THE FORECAST AREA. HIGH TEMPERATURES WILL BE AFFECTED VERY LITTLE WITH DROPS OF ABOUT 5 DEGREES FROM THE LOWER 90S TO THE MID 80S. DISAGREEMENT IN MODEL PRECIPITATION OCCURS ON SATURDAY...WITH MOST MODELS STAYING DRY WITH ANOTHER FRONTAL PASSAGE. THE GFS MODEL IS THE ONLY FORECAST THAT IS AGGRESSIVELY BRINGING WIDESPREAD HEAVIER PRECIPITATION SATURDAY NIGHT INTO EARLY SUNDAY MORNING. THE GFS SOLUTION SEEMED TO HEAVILY AFFECT CONSENSUS FORECASTS DESPITE OTHER FORECASTS REMAINING DRY. LOWERED POPS A BIT...ESPECIALLY FOR SOUTHWEST CORNER OF THE FORECAST AREA TO REMAIN WITHIN COLLABORATIVE THRESHOLDS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 330 AM MDT SUN JUN 21 2015 KGLD...VFR CONDITIONS EXPECTED. AN EAST WIND UNDER 10KTS WILL CONTINUE THROUGH 18Z BEFORE VEERING TO THE SOUTHEAST AND APPROACHING 12KTS BY 20Z. FROM 21Z-00Z WINDS FROM THE SOUTHEAST 12-15KTS WITH SOME HIGHER GUSTS. FOR THIS EVENING THROUGH EARLY OVERNIGHT SOUTH TO SOUTHWEST WINDS INCREASE INTO THE 15-20KT RANGE WITH HIGHER GUSTS AS A WARM FRONT MOVES NORTH OF THE AREA. AFTER 09Z WINDS SLOWLY VEER TO THE SOUTHWEST NEAR 13KTS AHEAD OF AN APPROACHING COLD FRONT. KMCK...MVFR CIGS EXPECTED FROM TAF ISSUANCE THROUGH 17Z OR SO BEFORE VFR CONDITIONS RETURN AND CONTINUE THROUGH THE REST OF THE TAF PERIOD. AN EAST WIND NEAR 10KTS EXPECTED FROM TAF ISSUANCE THROUGH 18Z BEFORE SLOWLY VEERING TO THE SOUTHEAST AT SIMILAR SPEEDS. SOUTHEAST WINDS OF 12-15KTS WITH SOME GUSTS EXPECTED FROM 03Z-06Z THEN SLOWLY VEER TO THE SOUTHWEST AND FALL BELOW 12KTS AFTER 09Z. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...BULLER SHORT TERM...99 LONG TERM...MK AVIATION...99
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1202 AM CDT SUN JUN 21 2015 ...UPDATE TO AVIATION... .SYNOPSIS... ISSUED AT 1030 PM CDT SAT JUN 20 2015 WV IMAGERY AND 00Z UPPER AIR ANALYSIS INDICATE A NORTHWESTERLY FLOW ALOFT PREVAILING ACROSS THE WESTERN HIGH PLAINS AS A WEAK UPPER LEVEL RIDGE OF HIGH PRESSURE TRANSITIONS EASTWARD ACROSS THE INTERMOUNTAIN WEST. NEAR THE SURFACE, A NEAR STATIONARY FRONTAL BOUNDARY EXTENDS FROM SOUTHWESTERN KANSAS NORTHEAST ACROSS CENTRAL KANSAS. && .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 313 PM CDT SAT JUN 20 2015 UPPER LEVEL WESTERLY FLOW CONTINUES TO BE SITUATED ACROSS THE NORTHERN CONUS TODAY WITH UPPER LEVEL HIGH PRESSURE CENTERED OVER THE DESERT SOUTHWEST. A WEAK MID LEVEL DISTURBANCE WAS MOVING EAST OVER NEBRASKA THIS AFTERNOON WHILE A STRONGER WAVE WAS MOVING OVER MONTANA. A COOL FRONT WAS SLOWLY PUSHING SOUTH FROM EASTERN COLORADO INTO NORTH CENTRAL KANSAS BY EARLY AFTERNOON. THE FRONT SHOULD MOVE SOUTH A LITTLE MORE EARLY THIS EVENING BEFORE BECOMING STATIONARY AND THEN SLOWLY LIFTING BACK TO THE NORTH LATER TONIGHT. THE RAP AND HRRR MODELS INDICATE SOME CONVECTION BREAKING OUT ALONG THE FRONT LATE THIS AFTERNOON. THESE ARE THE ONLY MODELS THAT DO SO AS THE HIRES ARW/NMM MODELS AS WELL AS THE OPERATIONAL NAM AND GFS KEEP THINGS DRY. THE MESOSCALE MODELS HAVE BEEN SHOWING A TENDENCY FOR CONVECTIVE TEMPERATURES TO BE REACHED IN CENTRAL KANSAS WHICH WOULD EXPLAIN THE CONVECTION. FOR NOW WILL KEEP THE FORECAST DRY IN CENTRAL KANSAS. TEMPERATURES TONIGHT WILL CONTINUE FAIRLY MILD IN THE MID 60S ALONG THE COLORADO BORDER TO THE LOWER 70S IN SOUTH CENTRAL KANSAS. SOUTHERLY WINDS WILL INCREASE AGAIN ON SUNDAY BUT SHOULD NOT HAVE QUITE THE DOWNSLOPE COMPONENT AS TODAY. IN SPITE OF THIS, WARMER AIR IN THE MID LEVELS WILL BE SPREADING OUT OF THE WEST AS THE UPPER LEVEL HIGH PRESSURE IN THE WEST MOVES TOWARD THE PLAINS. HIGHS WILL AGAIN BE VERY WARM...IN THE 95-100 DEGREE RANGE. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 248 PM CDT SAT JUN 20 2015 UPPER LEVEL RIDGING WILL PERSIST ACROSS THE SOUTHERN ROCKIES AND SOUTHERN PLAINS THROUGH MIDWEEK BEFORE SHIFTING WESTWARD INTO THE ROCKIES BY THURSDAY AND THEN AMPLIFYING OVER THE WESTERN UNITED STATES INTO THE WEEKEND. THIS WILL GENERALLY BE A HOT PATTERN, WITH LITTLE IN THE WAY OF PRECIPITATION. WEAK COLD FRONTS MAY GET CLOSE ENOUGH TO WESTERN KANSAS LATE TUESDAY THROUGH FRIDAY, PARTICULARLY NEAR INTERSTATE 70 SO THAT A FEW THUNDERSTORMS ARE POSSIBLE. BUT THESE STORMS OUGHT TO BE ISOLATED TO SCATTERED; AND GIVEN THE WEAK WINDS AT UPPER LEVELS, WILL PROBABLY NOT BE SEVERE OTHER THAN AN ISOLATED DAMAGING WIND GUST. IF THE UPPER LEVEL RIDGE RETROGRADES BACK OVER UTAH BY FRIDAY AND SATURDAY AS THE MODELS SUGGEST, THEN HIGH TEMPERATURES COULD DROP BACK INTO THE UPPER 80S TO LOWER 90S STARTING FRIDAY, ALONG WITH A FEW THUNDERSTORMS AS THE COLD FRONT PASSES. BUT UNTIL THEN, EXPECT HIGHS TO BE IN THE 90S TO POSSIBLY NEAR 100F, WITH LOWS IN THE UPPER 60S TO LOWER 70S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1200 AM CDT SUN JUN 21 2015 VFR CONDITIONS ARE EXPECTED TO PREVAIL AT ALL TAF SITES THROUGH LATE SUNDAY AFTERNOON. LIGHT EASTERLY WINDS WILL PREVAIL ACROSS CENTRAL KANSAS OVERNIGHT AS A FRONTAL BOUNDARY REMAINS STALLED OUT FROM SOUTHWEST KANSAS NORTHEAST INTO CENTRAL KANSAS. WINDS SOUTH OF THE BOUNDARY WILL BE SOUTHERLY 5 TO 15KT. THE FRONTAL BOUNDARY WILL LIFT BACK TO THE NORTH SUNDAY TURNING WINDS SOUTHERLY ACROSS THE ENTIRE REGION WHILE INCREASING UP TO AROUND 15 TO 25KT BY SUNDAY AFTERNOON. && .PRELIMINARY POINT TEMPS/POPS... DDC 71 96 71 96 / 0 0 0 0 GCK 70 101 71 99 / 0 0 0 0 EHA 69 100 69 97 / 0 0 0 0 LBL 69 97 70 96 / 0 0 0 0 HYS 73 101 72 97 / 0 10 10 10 P28 73 96 73 95 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJOHNSON SHORT TERM...GERARD LONG TERM...FINCH AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
908 PM EDT Mon Jun 22 2015 ...Forecast Update... Updated at 905 PM EDT Mon Jun 22 2015 Forecast is on track for the overnight period. Cirrus from convection upstream and earlier today will remain overhead. Complex of storms currently in southern/southeast Iowa will nose dive southward and is expected to weaken before approaching the area but likely to bring more cirrus for the overnight and morning hours. It may lay out an outflow boundary which could be the focus for thunderstorm development tomorrow. .SHORT TERM (Now through Tuesday Night)... Updated at 300 PM EDT Mon Jun 22 2015 ...Strong to Severe Storms Possible Tuesday Afternoon... Thunderstorms to our north in Michigan are sending plenty of subsiding cirrus our way this afternoon. Visible satellite imagery indicates our cumulus field is being held at bay because of this flow aloft, and latest radar over western KY shows earlier cells are decaying as well. Cannot rule out an isolated shower surviving in our southwest. Latest HRRR indicates a line of storms would fire in southeast Iowa/northern Illinois and head southeast through the evening, perhaps getting to our area as just a line of gusty winds or even a very isolated shower by daybreak Tuesday. Would expect wherever this boundary sets up to be the focus for further convection by late morning or early afternoon Tuesday. NAM soundings are very unstable for the afternoon, and surface temp/dewpoints are in line with what we expect tomorrow. Soundings show a layer of dry air in the 600-700 mb range, allowing the chance for both larger hail and stronger downburst winds. Bust potential for this forecast would be just how many clouds remain from the line that comes through overnight and how this affects surface temperatures. Clouds over LEX this hour are keeping temperatures ~5 degrees cooler than areas in the clear! Will highlight potential for severe wind gusts and hail in the stronger storms with our hazardous weather outlook. Again, highs Tuesday will depend greatly on extent of clouds in the morning. Based on current forecast, expect highs around 90. This should push heat indices into the mid to upper 90s for most locations. The best chance to get up to around 100 would be south of the I-64 corridor and west of a Bardstown to Glasgow line. .LONG TERM (Wednesday through Monday)... Issued at 300 PM EDT Mon Jun 22 2015 The synoptic pattern at the start of the long term period will feature an expansive ridge across the southern CONUS, placing the Ohio Valley on the periphery of the swift northwest flow found across much of the northern CONUS. This regime will amplify through the end of the long term period as the southern ridge breaks down and a trough builds into the Ohio Valley, bringing some relief from the precip chances and the hot and humid weather we`ve experienced as of late. Generally low-resolution synoptic models are notorious for struggling with convection and MCS development, so confidence in the long term period on timing and convective coverage is generally low, especially Wednesday. That being said, have attempted to best time the convection using a general model blend and ensemble data. This method brings just chance pops to the region Wednesday into Wednesday night, as there does not appear to be any substantial triggering PV anomaly to spark convection. By Thursday, the southern ridge will begin to break down as a strong trough dives into the northern CONUS. Timing as of now keeps much of the convection just north of the region through much of the daylight hours on Thursday. Good southwesterly flow ahead of an area of low pressure coupled with some expected sunshine and 850mb temps rising to around 20C means Thursday could end up being quite warm, assuming clouds/precip remain to the north. Have gone with highs in the low to mid 90s, which coupled with dewpoints in the low to mid 70s, will push heat index values on either side of 100 degrees. The trough and associated surface front will slowly push through the region Thursday night into Friday night. Mid-level flow will be sufficient to support some strong/severe storms, but the potential for storms Thursday night may hinder destabilization on Friday given the expected cloud cover. If we are able to see some sun break out on Friday, then a few strong/severe storms will be possible. Again, predictability in the mesoscale details at this timeframe are rather low, but the strength of the system pushing through does support the potential for some strong/severe storm development, especially across southern KY on Friday. Given the slow movement of the front through the area, we could also have some local flooding issues as well, so that will be something to continue to monitor. The passing cold front and building trough aloft will make for rather pleasant conditions moving in by the weekend. Temperatures will fall into the upper 70s and lower 80s for highs on Saturday and Sunday. Conditions should be generally dry Saturday night through Sunday, as the deeper moisture finally gets shunted to the east with the passing cold front. && .AVIATION (00Z TAF Update)... Updated at 735 PM EDT Mon Jun 22 2015 Should be a quiet night tonight. Fog is not expected to be a problem given high clouds overhead and a steady southwest breeze. Thunderstorms erupting to the northwest across Iowa and Illinois this evening will slide southeast tonight but should weaken as they approach the Ohio River. Can`t rule out a stray shower around dawn at SDF, but debris clouds and a possible outflow boundary should be the primary effects. During the day Tuesday the atmosphere will become very unstable. As the convective outflow and/or associated cold front move into the region scattered thunderstorms should develop in the afternoon, some of which could be strong. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........ZT Short Term.....RJS Long Term......KJD Aviation.......13
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
735 PM EDT Mon Jun 22 2015 ...Updated Aviation Discussion... .SHORT TERM (Now through Tuesday Night)... Updated at 300 PM EDT Mon Jun 22 2015 ...Strong to Severe Storms Possible Tuesday Afternoon... Thunderstorms to our north in Michigan are sending plenty of subsiding cirrus our way this afternoon. Visible satellite imagery indicates our cumulus field is being held at bay because of this flow aloft, and latest radar over western KY shows earlier cells are decaying as well. Cannot rule out an isolated shower surviving in our southwest. Latest HRRR indicates a line of storms would fire in southeast Iowa/northern Illinois and head southeast through the evening, perhaps getting to our area as just a line of gusty winds or even a very isolated shower by daybreak Tuesday. Would expect wherever this boundary sets up to be the focus for further convection by late morning or early afternoon Tuesday. NAM soundings are very unstable for the afternoon, and surface temp/dewpoints are in line with what we expect tomorrow. Soundings show a layer of dry air in the 600-700 mb range, allowing the chance for both larger hail and stronger downburst winds. Bust potential for this forecast would be just how many clouds remain from the line that comes through overnight and how this affects surface temperatures. Clouds over LEX this hour are keeping temperatures ~5 degrees cooler than areas in the clear! Will highlight potential for severe wind gusts and hail in the stronger storms with our hazardous weather outlook. Again, highs Tuesday will depend greatly on extent of clouds in the morning. Based on current forecast, expect highs around 90. This should push heat indices into the mid to upper 90s for most locations. The best chance to get up to around 100 would be south of the I-64 corridor and west of a Bardstown to Glasgow line. .LONG TERM (Wednesday through Monday)... Issued at 300 PM EDT Mon Jun 22 2015 The synoptic pattern at the start of the long term period will feature an expansive ridge across the southern CONUS, placing the Ohio Valley on the periphery of the swift northwest flow found across much of the northern CONUS. This regime will amplify through the end of the long term period as the southern ridge breaks down and a trough builds into the Ohio Valley, bringing some relief from the precip chances and the hot and humid weather we`ve experienced as of late. Generally low-resolution synoptic models are notorious for struggling with convection and MCS development, so confidence in the long term period on timing and convective coverage is generally low, especially Wednesday. That being said, have attempted to best time the convection using a general model blend and ensemble data. This method brings just chance pops to the region Wednesday into Wednesday night, as there does not appear to be any substantial triggering PV anomaly to spark convection. By Thursday, the southern ridge will begin to break down as a strong trough dives into the northern CONUS. Timing as of now keeps much of the convection just north of the region through much of the daylight hours on Thursday. Good southwesterly flow ahead of an area of low pressure coupled with some expected sunshine and 850mb temps rising to around 20C means Thursday could end up being quite warm, assuming clouds/precip remain to the north. Have gone with highs in the low to mid 90s, which coupled with dewpoints in the low to mid 70s, will push heat index values on either side of 100 degrees. The trough and associated surface front will slowly push through the region Thursday night into Friday night. Mid-level flow will be sufficient to support some strong/severe storms, but the potential for storms Thursday night may hinder destabilization on Friday given the expected cloud cover. If we are able to see some sun break out on Friday, then a few strong/severe storms will be possible. Again, predictability in the mesoscale details at this timeframe are rather low, but the strength of the system pushing through does support the potential for some strong/severe storm development, especially across southern KY on Friday. Given the slow movement of the front through the area, we could also have some local flooding issues as well, so that will be something to continue to monitor. The passing cold front and building trough aloft will make for rather pleasant conditions moving in by the weekend. Temperatures will fall into the upper 70s and lower 80s for highs on Saturday and Sunday. Conditions should be generally dry Saturday night through Sunday, as the deeper moisture finally gets shunted to the east with the passing cold front. && .AVIATION (00Z TAF Update)... Updated at 735 PM EDT Mon Jun 22 2015 Should be a quiet night tonight. Fog is not expected to be a problem given high clouds overhead and a steady southwest breeze. Thunderstorms erupting to the northwest across Iowa and Illinois this evening will slide southeast tonight but should weaken as they approach the Ohio River. Can`t rule out a stray shower around dawn at SDF, but debris clouds and a possible outflow boundary should be the primary effects. During the day Tuesday the atmosphere will become very unstable. As the convective outflow and/or associated cold front move into the region scattered thunderstorms should develop in the afternoon, some of which could be strong. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Short Term........RJS Long Term.........KJD Aviation..........13
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
554 PM EDT Sun Jun 21 2015 ...Mesoscale Forecast Update... Issued at 554 PM EDT Sun Jun 21 2015 After discussing with SPC and JKL, have dropped several counties from the northeast edge of the watch, since all the action is concentrated across west central and southern Kentucky and drifting southward. Considered dropping Hardin and LaRue counties as well, but decided to see what the storms around Leitchfield do first. .SHORT TERM (Now through Monday Night)... Updated at 244 PM EDT Sun Jun 21 2015 ...Strong to Severe Storms Possible Late This Afternoon into This Evening... The synoptic pattern early this afternoon features an expansive ridge building in across the southern CONUS, whose reach extends up into portions of southern KY. Further north, an active northern stream continues to send generally subtle PV anomalies through the flow, each of which continue to set off clusters of convection. The forecast for late this afternoon into this evening remains a rather difficult one, as there are many subtle features to contend with. Have fairly high confidence that any thunderstorm activity late this afternoon will be focused across central and southern KY. KLVX showed a nice boundary push through earlier this afternoon, and SPC mesoanalysis shows strong moisture convergence along it. The latest satellite loop confirms this, as a line of cumulus has now formed along the boundary. Along and south of this boundary is where the best coverage of storms will be this afternoon. Forecast soundings still suggest there will be a cap to contend with across central/southern KY which may help limit updraft intensity to some extent. However, MLCAPEs in this area have risen to 3000-4000 J/kg according to the latest mesoanalysis data (though this may be a bit overdone). This strong instability coupled with 20 to 30 knots of effective shear may lead to some loose storm organization. The high DCAPE environment suggest localized damaging wind gusts will be the main threat, although some quarter-sized hail will be possible as well given the strong instability in place. That activity should sag south by early this evening, as attention then shifts to the current convection ongoing over MO. The CAMs are really struggling with what will happen with this activity through the rest of the afternoon into this evening, as some want to keep it mainly elevated and fade it this evening, while others develop it into a severe linear MCS and plow it southeast into our region tonight around/after 00Z. The area downstream of this activity over IL has been slow to destabilize given a thick cirrus shield in place through much of the day, but that cirrus has now mostly dissipated. Dprog/dt of the typically reliable HRRR shows a very inconsistent solution, so confidence is low. Will go with a rather conservative approach to pops and keep them around 40 percent for the potential of this activity getting in here later tonight. If it does develop a cold pool and begin to bow out, then it could bring some severe wind gusts into portions of southern IN and KY later this evening, mainly west of I-65. Once this moves through, the rest of the overnight period will be mainly dry as upper-level ridging builds overhead. The ridge will really take hold Monday into Monday night, bringing mostly dry and hot conditions. Can`t completely rule out a stray storm Monday afternoon, but forcing mechanisms are lacking and the mid-level cap will be strong. Therefore, will go with a dry forecast. Highs will be in the low to mid 90s, with heat indices in excess of 100 degrees at times. Overnight lows on Monday will be quite muggy out ahead of another system slated to push through on Tuesday, with readings only dropping into the mid and upper 70s. .LONG TERM (Tuesday through Sunday)... Issued at 220 PM EDT Sun Jun 21 2015 Models have not changed much in their overall pattern, with a ridge near but centered just southwest of the region early on and then transition to a more dominant western ridge by the end of the work week, with troughing over us. That should mean hot days at first and a little cooler by the end of the work week, but with rain chances pretty much every day. && .AVIATION (18Z TAF Update)... Updated at 113 PM EDT Sun Jun 21 2015 Generally VFR conditions are expected through the TAF period, although restrictions may prevail in thunderstorms this afternoon and evening. The latest satellite and environment trends support the idea that storms will initiate mainly south of KLEX and KSDF, with little coverage expected around KSDF and KLEX. Therefore, have removed VCTS mention at those sites, but added it into KBWG where coverage is expected to be a bit better. Winds outside of storms will be out of the WSW with gusts of 15-20 knots at times. Confidence decreases a bit tonight, as convection across MO may congeal and make a run at all sites overnight. However, it has really struggled so far this morning and only a few guidance members have it getting into the terminals later tonight, so will leave out for now. Could be some light fog at KBWG and/or KLEX, but there once again may be some mid/upper level clouds from convection to limit any BR development, so will leave out for now. Despite the overnight early morning thunderstorm chances, tomorrow should be mainly dry as upper-level ridging builds in. VFR conditions are expected with winds out of the WSW at 10-15 knots with gusts to 20 knots. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Mesoscale......13 Short Term.....KJD Long Term......RJS Aviation.......KJD
AREA FORECAST DISCUSSION
NWS JACKSON KY
318 PM EDT SUN JUN 21 2015 .UPDATE... ISSUED AT 215 PM EDT SUN JUN 21 2015 HIGH RESOLUTION MODELS CONTINUE TO ADVERTISE A LINE OF CONVECTION DEVELOPING SOMEWHERE BETWEEN THE I64 CORRIDOR AND THE MOUNTAIN PARKAY. BASED ON SFC TEMPS WE SHOULD BEGIN TO SEE SHOWERS AND STORM FIRING OVER THE NEXT HOUR...AT MOST TWO. CONVECTION IS EXPECTED TO INITIATE ALONG AN OLD OUTFLOW THAT HAS DROPPED INTO THE AREA FROM LAST NIGHTS MCS ACTIVITY. BEST GUESS AT THE LOCATION OF THAT BOUNDARY WOULD BE ROUGHLY FROM JUST SOUTH OF SDF TO DVK AND THEN BACK NORTHEAST...POSSIBLY JUST SOUTH OF SYM. MADE ADJUSTMENTS TO THE FORECAST PACKAGE FOR LATEST THOUGHTS ALONG WITH GRID UPDATES TOWARDS LATEST HOURLY OBSERVATIONS. UPDATE ISSUED AT 1111 AM EDT SUN JUN 21 2015 UPDATE MAINLY TO REMOVE MORNING FOG FROM THE FORECAST PACKAGE. GRIDS...AND THE REST OF THE FORECAST WERE IN GOOD SHAPE. SEEING SOME PARTIAL CLEARING OUT THERE THIS MORNING. SOME OF THE DEBRIS FROM UPSTREAM MCS IS PASSING ACROSS THE AREA BUT THUS FAR AND FOR A LARGE PART THIS HAS BEEN DISSIPATING...ALLOWING OUR AIR MASS TO BEGIN THE PROCESS OF DESTABILIZATION. BEST SHEAR AND SFC BASED INSTABILITY IS CURRENTLY LOCATED ALONG THE OHIO RIVER. SEVERAL OF OUR HIGH RESOLUTION MODELS ARE GENERATING SIMILAR SOLUTIONS... DEVELOPING A LINE OF CONVECTION ALONG AND SOUTH OF INTERSTATE 64 BY 19-21Z BEFORE BRINGING THE LINE SOUTHWARD THROUGH THE REMAINDER OF THE LATE AFTERNOON AND EARLY EVENING. FORECAST SOUNDINGS DO SHOW A WEAK CAP IN PLACE UNTIL LATE THIS AFTERNOON BUT NOT REALLY SEEING THIS FEATURE IN THE MORNINGS 12Z SOUNDINGS. THIS CONVECTION APPEARS TO INITIATE ALONG A RESIDUAL OUTFLOW BOUNDARY THAT MAY BE SETTLING OVER OUR AREA THIS MORNING...LIKELY LEFT OVER FROM LAST NIGHTS UPSTREAM MCS ACTIVITY. IN GENERAL CONFIDENCE IS INCREASING FOR THE POTENTIAL OF A ROUND OF STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON...WITH CONVECTION PROBABLY INITIATING BY OR AFTER 3 PM...BUT BEFORE 5 PM. WILL CONTINUE TO MONITOR. UPDATE ISSUED AT 647 AM EDT SUN JUN 21 2015 THUNDERSTORM COMPLEX DISSIPATED BEFORE IT WAS ABLE TO MOVE INTO OUR NORTHWEST COUNTIES SO WILL REMOVE ANY MENTION OF RAIN UNTIL LATER THIS MORNING. NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 TODAY/S FORECAST IS A BIT MORE COMPLICATED THAN I WOULD LIKE DUE TO UPSTREAM MCS AND THE EFFECT IT/S DEBRIS CLOUDS WILL HAVE ON POTENTIAL CONVECTIVE DEVELOPMENT LATER TODAY ACROSS OUR AREA. BASED ON RAW EXTRAPOLATION...THE LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY OVER INDIANA WILL BE ENTERING OUR NORTHWEST COUNTIES BY AROUND DAWN. I EXPECT THIS LINE TO WEAKEN BUT A SMALL POP WILL BE INCLUDED UP NORTH EARLY ON TO ACCOUNT FOR THIS ACTIVITY. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS WILL LINGER THROUGH THE MORNING OVER THE OHIO VALLEY AND THIS SHOULD LIMIT DESTABILIZATION EARLY ON IN THE DAY DRAWING INTO QUESTION THE DEVELOPMENT OF ANOTHER COMPLEX OF STORMS SHOWN TO TAKE PLACE SO QUICKLY IN THE 21/00Z NAM OVER INDIANA AND OHIO. RECENT HRRR AND 21/00Z HIRES NMM SEEM MORE REASONABLE IN HOLDING OFF ANY SHOWER AND THUNDERSTORM DEVELOPMENT UNTIL LATER IN THE AFTERNOON. IT IS AT THIS TIME THAT AT LEAST SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER EASTERN KENTUCKY...AND THEY COULD BECOME QUITE STRONG AS THEY HAVE A RICH FUEL SOURCE OF LOW 70 DEGREE SURFACE DEW POINTS TO TAP INTO. SPC CONTINUES TO HIGHLIGHT A GOOD CHUNK OF THE AREA IN A SLIGHT RISK AND WILL CONTINUE TO MENTION THIS IN OUR LOCAL HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS THAT DEVELOP THIS AFTERNOON WILL SETTLE SOUTHEAST AND WEAKEN DURING THE EVENING. LEFT OVER BOUNDARIES MAY THEN BE THE FOCUS FOR ADDITIONAL THUNDERSTORM ACTIVITY ON MONDAY AFTERNOON...BUT THESE SHOULD REMAIN WIDELY SCATTERED AS AN UPPER LEVEL RIDGE STARTS TO BUILD IN FROM THE WEST. HEAT AND HUMIDITY WILL BE ANOTHER CONCERN DURING THE SHORT TERM. CLOUD COVER EARLY IN THE DAY TODAY SHOULD SLOW OUR RISE A BIT...BUT STILL EXPECT TEMPS TO REACH AROUND 90 BY AFTERNOON AND THEN AGAIN MONDAY AFTERNOON. WITH DEW POINTS PROGGED TO RISE INTO THE LOWER 70S FOR MOST LOCATIONS...AFTERNOON HEAT INDEX VALUES WILL RISE INTO THE MID TO UPPER 90S. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 318 PM EDT SUN JUN 21 2015 MODELS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT THROUGH NEXT WEEKEND. UNFORTUNATELY...THE HEAT...HUMIDITY...AND CHANCES FOR PRECIP ARE EXPECTED TO CONTINUE DURING THIS TIME AS WELL. WE WILL START OFF WITH A BROAD AREA OF RIDGING ACROSS THE SOUTHERN CONUS...CONTINUING TO REACH ITS WAY EASTWARD INTO THE OHIO RIVER VALLEY THROUGH THE DAY WEDNESDAY. MEANWHILE...A STRONG SHORTWAVE WILL PASS SOUTHWARD ALONG THE GREAT LAKES REGION...CREATING AN AREA OF PACKED ISOBARS AND STRONG WINDS JUST NORTH OF KENTUCKY. THE WNW FLOW THAT THIS CREATES WILL ALLOW SEVERAL SMALLER SHORTWAVES TO TRAVERSE THE REGION THROUGH THE WEEK...BRINGING OFF AND ON CHANCES OF PRECIP AND POSSIBILITIES FOR LARGER MCS DEVELOPMENT. BY THURSDAY...THE SHORTWAVE THAT MOVED ACROSS THE GREAT LAKES REGION WILL BECOME WRAPPED UP IN A STRENGTHENING UPPER LEVEL LOW OVER THE SOUTHEAST CANADIAN COAST. THIS WILL DEEPEN THE NORTHWEST FLOW ACROSS THE OHIO RIVER VALLEY...AND PUSH THE RIDGING TO OUR SOUTH BACK WESTWARD TOWARDS THE SOUTHERN PLAINS...AND EVENTUALLY THE FOUR CORNER STATES BY THURSDAY NIGHT. KINKS IN THIS NW FLOW /SMALL SHORTWAVES/ WILL CONTINUE TO SHIFT SE TOWARDS THE OHIO RIVER VALLEY AS THIS OCCURS...STRENGTHENING AS WE HEAD INTO THE WEEKEND AND THE LONG TERM MODELS TRY TO PRODUCE ANOTHER STRONG UPPER LEVEL LOW WHICH WILL LEAD TO A DIGGING TROUGH OVER MUCH OF THE EASTERN CONUS. WHILE THE EXACT TIMING OF THESE FEATURES IS STILL A BIT OFF THIS FAR OUT IN THE FORECAST...THE OVERALL PATTERN IS QUITE SIMILAR. AT THE SURFACE...LOW PRESSURE WILL SET UP BELOW THE CLOSED LOW MOVING FROM THE GREAT LAKES TO SOUTHEASTERN CANADA. FROM THIS LOW A FRONTAL BOUNDARY WILL EXTEND WESTWARD...BECOMING CAUGHT AND ELONGATED IN THE WSW FLOW ACROSS THE OHIO RIVER VALLEY. THIS BOUNDARY IS EXPECTED TO FLUCTUATE...SHIFTING NORTH AS THE NW FLOW DEEPENS...AND THEN BACK SOUTHWARD AGAIN AS THE LONGWAVE TROUGH BEGINS TO DIG FARTHER SOUTH. THE COMBINATION OF THIS BOUNDARY AND PASSING SHORTWAVES WILL CREATING THE RESULTING PRECIP CHANCES THROUGH THE WEEK. TEMPERATURES WILL BE WARMEST TUESDAY WITH SOUTHERLY FLOW STILL IN PLACE JUST AHEAD OF THE DROPPING COLD FRONT...THEN ARE EXPECTED TO FALL SLIGHTLY AS THE FRONT SHEARS OUT AND SHIFTS BACK AND FORTH ACROSS THE REGION. IF THE EXTENDED MODELS HOLD TRUE...THE DIGGING TROUGH LATE IN THE WEEKEND WILL RESULT IN A SURFACE LOW DEVELOPING JUST NORTH OF THE REGION...AND BRINGING OUR BEST WIDESPREAD CHANCE FOR PRECIP. GIVEN THE HOT AND HUMID CONDITIONS IN ADDITION TO THE CLOSE PROXIMITY OF THE BOUNDARY...EXPECT ANY PRECIP THAT DEVELOPS TO HAVE SOME THUNDER COMPONENT TO IT AND BE MOST PROMINENT DURING THE AFTERNOON AND EARLY EVENING HOURS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 215 PM EDT SUN JUN 21 2015 THERE APPEARS TO BE A CONVECTIVE OUTFLOW BOUNDARY THAT HAS SETTLED OVER THE COMMONWEALTH...LOCATED APPROXIMATELY FROM JUST SOUTH OF SDF TO DVK AND THEN BACK NORTHEAST...POSSIBLY JUST SOUTH OF SYM. BASED ON HIGH RESOLUTION MODELS EXPECTING THUNDERSTORMS TO FIRE UP IN THE VCNTY OF THIS SFC BOUNDARY THIS AFTERNOON ONCE WE HIT CONVECTIVE TEMPS...MID TO UPPER 80S OVER THE NEXT HOUR OR SO. HAVE MAINTAINED A MENTION OF THUNDERSTROMS IN THE TAFS AND WILL ADJUST ONCE WE HAVE A BETTER HANDLE ON TIMING. ALSO EXPECTING SOME GUSTY WINDS IN AND AROUND ANY THUNDERTSORMS THIS AFTERNOON AND EARLY THIS EVENING. HIGH BOUNDARY LAYER MOISTURE REMAINS IN PLACE TONIGHT FOR MORE FOG THROUGH THE OEVRNIGHT. WEST...SOUTHWEST SFC WINDS AT AROUND 5-8 KTS WILL CONTINUE THIS AFTERNOON, BECOMING LIGHT AND VARIABLE OVERNIGHT. THEN INCREASE BACK UP AROUND 5KT MONDAY. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...RAY SHORT TERM...ABE LONG TERM...JMW AVIATION...RAY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
243 PM EDT Sun Jun 21 2015 .SHORT TERM (Now through Monday Night)... Updated at 244 PM EDT Sun Jun 21 2015 ...Strong to Severe Storms Possible Late This Afternoon into This Evening... The synoptic pattern early this afternoon features an expansive ridge building in across the southern CONUS, whose reach extends up into portions of southern KY. Further north, an active northern stream continues to send generally subtle PV anomalies through the flow, each of which continue to set off clusters of convection. The forecast for late this afternoon into this evening remains a rather difficult one, as there are many subtle features to contend with. Have fairly high confidence that any thunderstorm activity late this afternoon will be focused across central and southern KY. KLVX showed a nice boundary push through earlier this afternoon, and SPC mesoanalysis shows strong moisture convergence along it. The latest satellite loop confirms this, as a line of cumulus has now formed along the boundary. Along and south of this boundary is where the best coverage of storms will be this afternoon. Forecast soundings still suggest there will be a cap to contend with across central/southern KY which may help limit updraft intensity to some extent. However, MLCAPEs in this area have risen to 3000-4000 J/kg according to the latest mesoanalysis data (though this may be a bit overdone). This strong instability coupled with 20 to 30 knots of effective shear may lead to some loose storm organization. The high DCAPE environment suggest localized damaging wind gusts will be the main threat, although some quarter-sized hail will be possible as well given the strong instability in place. That activity should sag south by early this evening, as attention then shifts to the current convection ongoing over MO. The CAMs are really struggling with what will happen with this activity through the rest of the afternoon into this evening, as some want to keep it mainly elevated and fade it this evening, while others develop it into a severe linear MCS and plow it southeast into our region tonight around/after 00Z. The area downstream of this activity over IL has been slow to destabilize given a thick cirrus shield in place through much of the day, but that cirrus has now mostly dissipated. Dprog/dt of the typically reliable HRRR shows a very inconsistent solution, so confidence is low. Will go with a rather conservative approach to pops and keep them around 40 percent for the potential of this activity getting in here later tonight. If it does develop a cold pool and begin to bow out, then it could bring some severe wind gusts into portions of southern IN and KY later this evening, mainly west of I-65. Once this moves through, the rest of the overnight period will be mainly dry as upper-level ridging builds overhead. The ridge will really take hold Monday into Monday night, bringing mostly dry and hot conditions. Can`t completely rule out a stray storm Monday afternoon, but forcing mechanisms are lacking and the mid-level cap will be strong. Therefore, will go with a dry forecast. Highs will be in the low to mid 90s, with heat indices in excess of 100 degrees at times. Overnight lows on Monday will be quite muggy out ahead of another system slated to push through on Tuesday, with readings only dropping into the mid and upper 70s. .LONG TERM (Tuesday through Sunday)... Issued at 220 PM EDT Sun Jun 21 2015 Models have not changed much in their overall pattern, with a ridge near but centered just southwest of the region early on and then transition to a more dominant western ridge by the end of the work week, with troughing over us. That should mean hot days at first and a little cooler by the end of the work week, but with rain chances pretty much every day. && .AVIATION (18Z TAF Update)... Updated at 113 PM EDT Sun Jun 21 2015 Generally VFR conditions are expected through the TAF period, although restrictions may prevail in thunderstorms this afternoon and evening. The latest satellite and environment trends support the idea that storms will initiate mainly south of KLEX and KSDF, with little coverage expected around KSDF and KLEX. Therefore, have removed VCTS mention at those sites, but added it into KBWG where coverage is expected to be a bit better. Winds outside of storms will be out of the WSW with gusts of 15-20 knots at times. Confidence decreases a bit tonight, as convection across MO may congeal and make a run at all sites overnight. However, it has really struggled so far this morning and only a few guidance members have it getting into the terminals later tonight, so will leave out for now. Could be some light fog at KBWG and/or KLEX, but there once again may be some mid/upper level clouds from convection to limit any BR development, so will leave out for now. Despite the overnight early morning thunderstorm chances, tomorrow should be mainly dry as upper-level ridging builds in. VFR conditions are expected with winds out of the WSW at 10-15 knots with gusts to 20 knots. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Short Term........KJD Long Term.........RJS Aviation..........KJD
AREA FORECAST DISCUSSION
NWS JACKSON KY
215 PM EDT SUN JUN 21 2015 .UPDATE... ISSUED AT 215 PM EDT SUN JUN 21 2015 HIGH RESOLUTION MODELS CONTINUE TO ADVERTISE A LINE OF CONVECTION DEVELOPING SOMEWHERE BETWEEN THE I64 CORRIDOR AND THE MOUNTAIN PARKAY. BASED ON SFC TEMPS WE SHOULD BEGIN TO SEE SHOWERS AND STORM FIRING OVER THE NEXT HOUR...AT MOST TWO. CONVECTION IS EXPECTED TO INITIATE ALONG AN OLD OUTFLOW THAT HAS DROPPED INTO THE AREA FROM LAST NIGHTS MCS ACTIVITY. BEST GUESS AT THE LOCATION OF THAT BOUNDARY WOULD BE ROUGHLY FROM JUST SOUTH OF SDF TO DVK AND THEN BACK NORTHEAST...POSSIBLY JUST SOUTH OF SYM. MADE ADJUSTMENTS TO THE FORECAST PACKAGE FOR LATEST THOUGHTS ALONG WITH GRID UPDATES TOWARDS LATEST HOURLY OBSERVATIONS. UPDATE ISSUED AT 1111 AM EDT SUN JUN 21 2015 UPDATE MAINLY TO REMOVE MORNING FOG FROM THE FORECAST PACKAGE. GRIDS...AND THE REST OF THE FORECAST WERE IN GOOD SHAPE. SEEING SOME PARTIAL CLEARING OUT THERE THIS MORNING. SOME OF THE DEBRIS FROM UPSTREAM MCS IS PASSING ACROSS THE AREA BUT THUS FAR AND FOR A LARGE PART THIS HAS BEEN DISSIPATING...ALLOWING OUR AIR MASS TO BEGIN THE PROCESS OF DESTABILIZATION. BEST SHEAR AND SFC BASED INSTABILITY IS CURRENTLY LOCATED ALONG THE OHIO RIVER. SEVERAL OF OUR HIGH RESOLUTION MODELS ARE GENERATING SIMILAR SOLUTIONS... DEVELOPING A LINE OF CONVECTION ALONG AND SOUTH OF INTERSTATE 64 BY 19-21Z BEFORE BRINGING THE LINE SOUTHWARD THROUGH THE REMAINDER OF THE LATE AFTERNOON AND EARLY EVENING. FORECAST SOUNDINGS DO SHOW A WEAK CAP IN PLACE UNTIL LATE THIS AFTERNOON BUT NOT REALLY SEEING THIS FEATURE IN THE MORNINGS 12Z SOUNDINGS. THIS CONVECTION APPEARS TO INITIATE ALONG A RESIDUAL OUTFLOW BOUNDARY THAT MAY BE SETTLING OVER OUR AREA THIS MORNING...LIKELY LEFT OVER FROM LAST NIGHTS UPSTREAM MCS ACTIVITY. IN GENERAL CONFIDENCE IS INCREASING FOR THE POTENTIAL OF A ROUND OF STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON...WITH CONVECTION PROBABLY INITIATING BY OR AFTER 3 PM...BUT BEFORE 5 PM. WILL CONTINUE TO MONITOR. UPDATE ISSUED AT 647 AM EDT SUN JUN 21 2015 THUNDERSTORM COMPLEX DISSIPATED BEFORE IT WAS ABLE TO MOVE INTO OUR NORTHWEST COUNTIES SO WILL REMOVE ANY MENTION OF RAIN UNTIL LATER THIS MORNING. NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 TODAY/S FORECAST IS A BIT MORE COMPLICATED THAN I WOULD LIKE DUE TO UPSTREAM MCS AND THE EFFECT IT/S DEBRIS CLOUDS WILL HAVE ON POTENTIAL CONVECTIVE DEVELOPMENT LATER TODAY ACROSS OUR AREA. BASED ON RAW EXTRAPOLATION...THE LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY OVER INDIANA WILL BE ENTERING OUR NORTHWEST COUNTIES BY AROUND DAWN. I EXPECT THIS LINE TO WEAKEN BUT A SMALL POP WILL BE INCLUDED UP NORTH EARLY ON TO ACCOUNT FOR THIS ACTIVITY. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS WILL LINGER THROUGH THE MORNING OVER THE OHIO VALLEY AND THIS SHOULD LIMIT DESTABILIZATION EARLY ON IN THE DAY DRAWING INTO QUESTION THE DEVELOPMENT OF ANOTHER COMPLEX OF STORMS SHOWN TO TAKE PLACE SO QUICKLY IN THE 21/00Z NAM OVER INDIANA AND OHIO. RECENT HRRR AND 21/00Z HIRES NMM SEEM MORE REASONABLE IN HOLDING OFF ANY SHOWER AND THUNDERSTORM DEVELOPMENT UNTIL LATER IN THE AFTERNOON. IT IS AT THIS TIME THAT AT LEAST SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER EASTERN KENTUCKY...AND THEY COULD BECOME QUITE STRONG AS THEY HAVE A RICH FUEL SOURCE OF LOW 70 DEGREE SURFACE DEW POINTS TO TAP INTO. SPC CONTINUES TO HIGHLIGHT A GOOD CHUNK OF THE AREA IN A SLIGHT RISK AND WILL CONTINUE TO MENTION THIS IN OUR LOCAL HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS THAT DEVELOP THIS AFTERNOON WILL SETTLE SOUTHEAST AND WEAKEN DURING THE EVENING. LEFT OVER BOUNDARIES MAY THEN BE THE FOCUS FOR ADDITIONAL THUNDERSTORM ACTIVITY ON MONDAY AFTERNOON...BUT THESE SHOULD REMAIN WIDELY SCATTERED AS AN UPPER LEVEL RIDGE STARTS TO BUILD IN FROM THE WEST. HEAT AND HUMIDITY WILL BE ANOTHER CONCERN DURING THE SHORT TERM. CLOUD COVER EARLY IN THE DAY TODAY SHOULD SLOW OUR RISE A BIT...BUT STILL EXPECT TEMPS TO REACH AROUND 90 BY AFTERNOON AND THEN AGAIN MONDAY AFTERNOON. WITH DEW POINTS PROGGED TO RISE INTO THE LOWER 70S FOR MOST LOCATIONS...AFTERNOON HEAT INDEX VALUES WILL RISE INTO THE MID TO UPPER 90S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE PERIOD. AN UPPER LEVEL RIDGE WILL START OUT ACROSS THE SOUTHERN PLAINS AND MISSISSIPPI VALLEY. THIS RIDGE WILL GRADUALLY WEAKEN AND GET DIRECTED TOWARD THE EAST...AS TRAVERSING NORTHERN STREAM SHORT WAVE ENERGY PROVIDES GLANCING BLOWS THROUGH EARLY NEXT WEEK. TOWARDS THE MIDDLE AND ESPECIALLY THE END OF NEXT WEEK...THE RIDGE WILL RE-ESTABLISH ITSELF ACROSS THE DESERT SOUTHWEST...ALLOWING FOR MORE TROUGHING TO RESIDE ACROSS THE MISSISSIPPI VALLEY. FOR EASTERN KENTUCKY...THIS WILL TRANSLATE INTO PLENTY OF HEAT AND HUMIDITY EARLY ON...ALONG WITH THE DAILY THREAT OF THUNDERSTORMS...MOST LIKELY PEAKING WITHIN THE NORMAL DIURNAL REGIME...ALTHOUGH AS MENTIONED PREVIOUSLY...LARGER THUNDERSTORM COMPLEX ACTIVITY WILL ALSO PLAY A ROLE. HIGHS WILL PEAK IN THE LOW 90S FOR MOST LOCATIONS THROUGH TUESDAY...BEFORE TAKING A BIT OF A HIT AS A SHEARED OUT COLD FRONT ATTEMPTS TO MOVE IN FROM THE NORTHWEST. HIGHS WILL DROP BACK INTO MAINLY THE 80S FOR THE SECOND HALF OF THE WORKWEEK...WITH SOME RELIEF FROM THE HUMIDITY BY THE START OF NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 215 PM EDT SUN JUN 21 2015 THERE APPEARS TO BE A CONVECTIVE OUTFLOW BOUNDARY THAT HAS SETTLED OVER THE COMMONWEALTH...LOCATED APPROXIMATELY FROM JUST SOUTH OF SDF TO DVK AND THEN BACK NORTHEAST...POSSIBLY JUST SOUTH OF SYM. BASED ON HIGH RESOLUTION MODELS EXPECTING THUNDERSTORMS TO FIRE UP IN THE VCNTY OF THIS SFC BOUNDARY THIS AFTERNOON ONCE WE HIT CONVECTIVE TEMPS...MID TO UPPER 80S OVER THE NEXT HOUR OR SO. HAVE MAINTAINED A MENTION OF THUNDERSTROMS IN THE TAFS AND WILL ADJUST ONCE WE HAVE A BETTER HANDLE ON TIMING. ALSO EXPECTING SOME GUSTY WINDS IN AND AROUND ANY THUNDERTSORMS THIS AFTERNOON AND EARLY THIS EVENING. HIGH BOUNDARY LAYER MOISTURE REMAINS IN PLACE TONIGHT FOR MORE FOG THROUGH THE OEVRNIGHT. WEST...SOUTHWEST SFC WINDS AT AROUND 5-8 KTS WILL CONTINUE THIS AFTERNOON, BECOMING LIGHT AND VARIABLE OVERNIGHT. THEN INCREASE BACK UP AROUND 5KT MONDAY. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...ABE LONG TERM...GEOGERIAN AVIATION...RAY
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
116 PM EDT Sun Jun 21 2015 ...Updated Aviation Discussion... ...Forecast Update... Updated at 1020 AM EDT Sun Jun 21 2015 Wanted to give an updated on expected storm evolution this afternoon. The latest guidance and satellite trends give growing confidence that the storm initiation zone may end up being along and south of the Ohio River. A thick cirrus shield from the convection near Saint Louis, MO continues to push into southern Indiana and even northern KY. This cloud canopy has provided a pretty good differential heating boundary, with southern Indiana in the lower 70s and Louisville sitting at 80 degrees. Additionally, a dew point gradient can be found along the Ohio River, with low to mid 70s to the south and mid/upper 60s to the north. Therefore, think storms will likely initiate along this boundary this afternoon (as the latest HRRR runs suggest), then spread into portions of central and even southern KY. The good news with this more southern initiation is that southern IN may see less of a threat for strong/severe storms. Additionally, the deep-layer shear (0-6km) decreases to the south of central/southern KY, so storms look to only have around 30 knots of shear to work with. This amount of shear will still be sufficient for a few severe storms, with the main threat being damaging winds and hail to around quarter-sized being a secondary threat. Will have to watch the upstream evolution today for a potential MCS this afternoon. Guidance is split on whether the convection now firing near Kansas City, MO will organize into a linear system that may push into our area this evening. Will leave forecast as is for now and continue to monitor this scenario over the coming hours. .SHORT TERM (Now through Monday)... Updated at 317 AM EDT Sun Jun 21 2015 ...Strong to Severe Storms Possible This Afternoon and Evening... The remnants of the MCS that has been moving through IL and IN this morning is about to move into our southern Indiana counties. These storms are expected to continue to weaken and dissipate across the area this morning as the move into a more stable airmass. The main concern today will be the possibility of strong to severe storms this afternoon. A slowly moving from will approach from the north this afternoon. A weak vortmax will interact with this boundary this afternoon as the atmosphere is destabilizing, sparking storm development by mid to late afternoon. There are a couple of things making this forecast tricky for the afternoon, especially with timing, but also the area that will see the most storms. The first is where any remnant boundaries from this morning`s convection end up. These could serve as a focus for storm initiation. The other will be cloud debris from the MCS. How quickly this erodes and how thick it is will play a role in destabilization as well. The edge may serve as a differential heating boundary. The models are struggling with this as well. GFS/NAM place the highest chance for storms across southern IN and north central KY closer to the front and the better upper level support. However, the WRF NMM and ARW have convection firing south of the Ohio River and moving to the south through the afternoon hours. Evolution of the cloud shield and boundaries definitely bears monitoring today. Regardless of placement, some strong to marginally severe storms will be possible. Plenty of moisture will pool ahead of the front with dewpoints in the low to mid 70s expected. Soundings show the potential for 1000-3000 J/kg CAPE. However, shear will be marginal around 30 knots and maximized across the northern half of the forecast area. Strong winds will be the main threat with the strongest storms with some small hail possible. Convection should diminish late this evening and things should be mostly quiet overnight. Another wave will move through on Monday sparking storms in the late morning to afternoon. The best chance for storms will be across southern IN and portions of the Bluegrass. The other concern will be the hot temperatures. Highs today will be in the upper 80s to lower 90s with lower 90s in most locations on Monday. Heat index values will peak in the upper 90s to low 100s. These high heat index values can lead to overheating if precautions are not taken. .LONG TERM (Monday Night through Saturday)... Issued at 325 AM EDT Sun Jun 21 2015 The majority of the week will feature ridging over much of the southern U.S. with active westerly flow over the northern U.S. The Ohio Valley will be on the edge of these zones making for a tricky forecast as far as precipitation chances. Troughing does look to attempt to push into the Midwest next weekend, providing at least a cool down but continued on and off precipitation chances. Tuesday - Wednesday... Tues and Wed will be the hottest days in the long term period with ridging strongest in our area on these days. Look for temps to top out in the upper 80s to mid 90s. Humid conditions will exist Tues/Wed with dewpts reaching the low to mid 70s both days. The humidity combined with the hot temps will result in heat indices reaching the 100-105 degree range each afternoon. While these numbers fall just shy of heat advisory criteria, feel the hot/humid conditions are still worth a mention in an SPS. Night time lows will stay in the low to mid 70s. As for precipitation chances, a sfc front should drop south into the Ohio Valley late in the day Tues providing a focus for showers/storms. Although we`ll lack good wind shear, plenty of instability will exist with CAPE values on the order of 3000-4000 J/KG. Thus, think that some strong storms will be possible with gusty winds and potentially some small hail being the main threats. Late Tue night, models indicate an MCS will develop to our WNW and push ESE into our region during the day on Wed. Again wind shear looks unimpressive but CAPE values have the potential to soar quite high again if we can get enough breaks in the clouds Wed morning. Thus, we could again see strong storms Wed as well. Thursday - Saturday... For Thursday and Friday, the ridge will start to break down over the Ohio Valley allowing the active westerly flow to sink into our region. This type of flow will feature multiple hard to time shortwaves which will cause showers/storms. Have limited POPs to 20-50% in the long term period due to lack of confidence in timing. Better forcing for storms may be present for next weekend if a more significant shortwave trough can develop as some models suggest. Temperatures/humidity should generally be on the decline through the weekend. While highs on Thurs should still be in the upper 80s/lower 90s, dewpts should be slightly lower resulting in heat indices below 100. By Saturday, high temps should fall back into the low to mid 80s. && .AVIATION (18Z TAF Update)... Updated at 113 PM EDT Sun Jun 21 2015 Generally VFR conditions are expected through the TAF period, although restrictions may prevail in thunderstorms this afternoon and evening. The latest satellite and environment trends support the idea that storms will initiate mainly south of KLEX and KSDF, with little coverage expected around KSDF and KLEX. Therefore, have removed VCTS mention at those sites, but added it into KBWG where coverage is expected to be a bit better. Winds outside of storms will be out of the WSW with gusts of 15-20 knots at times. Confidence decreases a bit tonight, as convection across MO may congeal and make a run at all sites overnight. However, it has really struggled so far this morning and only a few guidance members have it getting into the terminals later tonight, so will leave out for now. Could be some light fog at KBWG and/or KLEX, but there once again may be some mid/upper level clouds from convection to limit any BR development, so will leave out for now. Despite the overnight early morning thunderstorm chances, tomorrow should be mainly dry as upper-level ridging builds in. VFR conditions are expected with winds out of the WSW at 10-15 knots with gusts to 20 knots. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....EER Long Term......AMS Aviation.......KJD
AREA FORECAST DISCUSSION
NWS JACKSON KY
1111 AM EDT SUN JUN 21 2015 .UPDATE... ISSUED AT 1111 AM EDT SUN JUN 21 2015 UPDATE MAINLY TO REMOVE MORNING FOG FROM THE FORECAST PACKAGE. GRIDS...AND THE REST OF THE FORECAST WERE IN GOOD SHAPE. SEEING SOME PARTIAL CLEARING OUT THERE THIS MORNING. SOME OF THE DEBRIS FROM UPSTREAM MCS IS PASSING ACROSS THE AREA BUT THUS FAR AND FOR A LARGE PART THIS HAS BEEN DISSIPATING...ALLOWING OUR AIR MASS TO BEGIN THE PROCESS OF DESTABILIZATION. BEST SHEAR AND SFC BASED INSTABILITY IS CURRENTLY LOCATED ALONG THE OHIO RIVER. SEVERAL OF OUR HIGH RESOLUTION MODELS ARE GENERATING SIMILAR SOLUTIONS... DEVELOPING A LINE OF CONVECTION ALONG AND SOUTH OF INTERSTATE 64 BY 19-21Z BEFORE BRINGING THE LINE SOUTHWARD THROUGH THE REMAINDER OF THE LATE AFTERNOON AND EARLY EVENING. FORECAST SOUNDINGS DO SHOW A WEAK CAP IN PLACE UNTIL LATE THIS AFTERNOON BUT NOT REALLY SEEING THIS FEATURE IN THE MORNINGS 12Z SOUNDINGS. THIS CONVECTION APPEARS TO INITIATE ALONG A RESIDUAL OUTFLOW BOUNDARY THAT MAY BE SETTLING OVER OUR AREA THIS MORNING...LIKELY LEFT OVER FROM LAST NIGHTS UPSTREAM MCS ACTIVITY. IN GENERAL CONFIDENCE IS INCREASING FOR THE POTENTIAL OF A ROUND OF STRONG TO SEVERE THUNDERSTORMS LATE THIS AFTERNOON...WITH CONVECTION PROBABLY INITIATING BY OR AFTER 3 PM...BUT BEFORE 5 PM. WILL CONTINUE TO MONITOR. UPDATE ISSUED AT 647 AM EDT SUN JUN 21 2015 THUNDERSTORM COMPLEX DISSIPATED BEFORE IT WAS ABLE TO MOVE INTO OUR NORTHWEST COUNTIES SO WILL REMOVE ANY MENTION OF RAIN UNTIL LATER THIS MORNING. NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 TODAY/S FORECAST IS A BIT MORE COMPLICATED THAN I WOULD LIKE DUE TO UPSTREAM MCS AND THE EFFECT IT/S DEBRIS CLOUDS WILL HAVE ON POTENTIAL CONVECTIVE DEVELOPMENT LATER TODAY ACROSS OUR AREA. BASED ON RAW EXTRAPOLATION...THE LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY OVER INDIANA WILL BE ENTERING OUR NORTHWEST COUNTIES BY AROUND DAWN. I EXPECT THIS LINE TO WEAKEN BUT A SMALL POP WILL BE INCLUDED UP NORTH EARLY ON TO ACCOUNT FOR THIS ACTIVITY. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS WILL LINGER THROUGH THE MORNING OVER THE OHIO VALLEY AND THIS SHOULD LIMIT DESTABILIZATION EARLY ON IN THE DAY DRAWING INTO QUESTION THE DEVELOPMENT OF ANOTHER COMPLEX OF STORMS SHOWN TO TAKE PLACE SO QUICKLY IN THE 21/00Z NAM OVER INDIANA AND OHIO. RECENT HRRR AND 21/00Z HIRES NMM SEEM MORE REASONABLE IN HOLDING OFF ANY SHOWER AND THUNDERSTORM DEVELOPMENT UNTIL LATER IN THE AFTERNOON. IT IS AT THIS TIME THAT AT LEAST SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER EASTERN KENTUCKY...AND THEY COULD BECOME QUITE STRONG AS THEY HAVE A RICH FUEL SOURCE OF LOW 70 DEGREE SURFACE DEW POINTS TO TAP INTO. SPC CONTINUES TO HIGHLIGHT A GOOD CHUNK OF THE AREA IN A SLIGHT RISK AND WILL CONTINUE TO MENTION THIS IN OUR LOCAL HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS THAT DEVELOP THIS AFTERNOON WILL SETTLE SOUTHEAST AND WEAKEN DURING THE EVENING. LEFT OVER BOUNDARIES MAY THEN BE THE FOCUS FOR ADDITIONAL THUNDERSTORM ACTIVITY ON MONDAY AFTERNOON...BUT THESE SHOULD REMAIN WIDELY SCATTERED AS AN UPPER LEVEL RIDGE STARTS TO BUILD IN FROM THE WEST. HEAT AND HUMIDITY WILL BE ANOTHER CONCERN DURING THE SHORT TERM. CLOUD COVER EARLY IN THE DAY TODAY SHOULD SLOW OUR RISE A BIT...BUT STILL EXPECT TEMPS TO REACH AROUND 90 BY AFTERNOON AND THEN AGAIN MONDAY AFTERNOON. WITH DEW POINTS PROGGED TO RISE INTO THE LOWER 70S FOR MOST LOCATIONS...AFTERNOON HEAT INDEX VALUES WILL RISE INTO THE MID TO UPPER 90S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE PERIOD. AN UPPER LEVEL RIDGE WILL START OUT ACROSS THE SOUTHERN PLAINS AND MISSISSIPPI VALLEY. THIS RIDGE WILL GRADUALLY WEAKEN AND GET DIRECTED TOWARD THE EAST...AS TRAVERSING NORTHERN STREAM SHORT WAVE ENERGY PROVIDES GLANCING BLOWS THROUGH EARLY NEXT WEEK. TOWARDS THE MIDDLE AND ESPECIALLY THE END OF NEXT WEEK...THE RIDGE WILL RE-ESTABLISH ITSELF ACROSS THE DESERT SOUTHWEST...ALLOWING FOR MORE TROUGHING TO RESIDE ACROSS THE MISSISSIPPI VALLEY. FOR EASTERN KENTUCKY...THIS WILL TRANSLATE INTO PLENTY OF HEAT AND HUMIDITY EARLY ON...ALONG WITH THE DAILY THREAT OF THUNDERSTORMS...MOST LIKELY PEAKING WITHIN THE NORMAL DIURNAL REGIME...ALTHOUGH AS MENTIONED PREVIOUSLY...LARGER THUNDERSTORM COMPLEX ACTIVITY WILL ALSO PLAY A ROLE. HIGHS WILL PEAK IN THE LOW 90S FOR MOST LOCATIONS THROUGH TUESDAY...BEFORE TAKING A BIT OF A HIT AS A SHEARED OUT COLD FRONT ATTEMPTS TO MOVE IN FROM THE NORTHWEST. HIGHS WILL DROP BACK INTO MAINLY THE 80S FOR THE SECOND HALF OF THE WORKWEEK...WITH SOME RELIEF FROM THE HUMIDITY BY THE START OF NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 647 AM EDT SUN JUN 21 2015 PATCHY MVFR CLOUDS AND FOG WILL SLOWLY GIVE WAY TO VFR CONDITIONS OVER THE NEXT HOUR OR TWO. A HOT AND HUMID DAY IS EXPECTED WITH SCATTERED THUNDERSTORMS DEVELOPING DURING THE AFTERNOON. ANY THUNDERSTORM THAT DEVELOPS WILL POTENTIALLY BECOME SEVERE WITH DAMAGING WINDS AND HAIL POSSIBLE. STORMS ARE EXPECTED TO DIMINISH DURING THE EVENING HOURS...FOLLOWED BY THE DEVELOPMENT OF PATCHY VALLEY FOG OVERNIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES...NONE. && $$ UPDATE...RAY SHORT TERM...ABE LONG TERM...GEOGERIAN AVIATION...ABE
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1022 AM EDT Sun Jun 21 2015 ...Forecast Update... Updated at 1020 AM EDT Sun Jun 21 2015 Wanted to give an updated on expected storm evolution this afternoon. The latest guidance and satellite trends give growing confidence that the storm initiation zone may end up being along and south of the Ohio River. A thick cirrus shield from the convection near Saint Louis, MO continues to push into southern Indiana and even northern KY. This cloud canopy has provided a pretty good differential heating boundary, with southern Indiana in the lower 70s and Louisville sitting at 80 degrees. Additionally, a dew point gradient can be found along the Ohio River, with low to mid 70s to the south and mid/upper 60s to the north. Therefore, think storms will likely initiate along this boundary this afternoon (as the latest HRRR runs suggest), then spread into portions of central and even southern KY. The good news with this more southern initiation is that southern IN may see less of a threat for strong/severe storms. Additionally, the deep-layer shear (0-6km) decreases over central/southern KY, so storms look to only have around 30 knots of shear to work with. This amount of shear will still be sufficient for a few severe storms, with the main threat being damaging winds and hail to around quarter-sized being a secondary threat. Will have to watch the upstream evolution today for a potential MCS this afternoon. Guidance is split on whether the convection now firing near Kansas City, MO will organize into a linear system that may push into our area this evening. Will leave forecast as is for now and continue to monitor this scenario over the coming hours. .SHORT TERM (Now through Monday)... Updated at 317 AM EDT Sun Jun 21 2015 ...Strong to Severe Storms Possible This Afternoon and Evening... The remnants of the MCS that has been moving through IL and IN this morning is about to move into our southern Indiana counties. These storms are expected to continue to weaken and dissipate across the area this morning as the move into a more stable airmass. The main concern today will be the possibility of strong to severe storms this afternoon. A slowly moving from will approach from the north this afternoon. A weak vortmax will interact with this boundary this afternoon as the atmosphere is destabilizing, sparking storm development by mid to late afternoon. There are a couple of things making this forecast tricky for the afternoon, especially with timing, but also the area that will see the most storms. The first is where any remnant boundaries from this morning`s convection end up. These could serve as a focus for storm initiation. The other will be cloud debris from the MCS. How quickly this erodes and how thick it is will play a role in destabilization as well. The edge may serve as a differential heating boundary. The models are struggling with this as well. GFS/NAM place the highest chance for storms across southern IN and north central KY closer to the front and the better upper level support. However, the WRF NMM and ARW have convection firing south of the Ohio River and moving to the south through the afternoon hours. Evolution of the cloud shield and boundaries definitely bears monitoring today. Regardless of placement, some strong to marginally severe storms will be possible. Plenty of moisture will pool ahead of the front with dewpoints in the low to mid 70s expected. Soundings show the potential for 1000-3000 J/kg CAPE. However, shear will be marginal around 30 knots and maximized across the northern half of the forecast area. Strong winds will be the main threat with the strongest storms with some small hail possible. Convection should diminish late this evening and things should be mostly quiet overnight. Another wave will move through on Monday sparking storms in the late morning to afternoon. The best chance for storms will be across southern IN and portions of the Bluegrass. The other concern will be the hot temperatures. Highs today will be in the upper 80s to lower 90s with lower 90s in most locations on Monday. Heat index values will peak in the upper 90s to low 100s. These high heat index values can lead to overheating if precautions are not taken. .LONG TERM (Monday Night through Saturday)... Issued at 325 AM EDT Sun Jun 21 2015 The majority of the week will feature ridging over much of the southern U.S. with active westerly flow over the northern U.S. The Ohio Valley will be on the edge of these zones making for a tricky forecast as far as precipitation chances. Troughing does look to attempt to push into the Midwest next weekend, providing at least a cool down but continued on and off precipitation chances. Tuesday - Wednesday... Tues and Wed will be the hottest days in the long term period with ridging strongest in our area on these days. Look for temps to top out in the upper 80s to mid 90s. Humid conditions will exist Tues/Wed with dewpts reaching the low to mid 70s both days. The humidity combined with the hot temps will result in heat indices reaching the 100-105 degree range each afternoon. While these numbers fall just shy of heat advisory criteria, feel the hot/humid conditions are still worth a mention in an SPS. Night time lows will stay in the low to mid 70s. As for precipitation chances, a sfc front should drop south into the Ohio Valley late in the day Tues providing a focus for showers/storms. Although we`ll lack good wind shear, plenty of instability will exist with CAPE values on the order of 3000-4000 J/KG. Thus, think that some strong storms will be possible with gusty winds and potentially some small hail being the main threats. Late Tue night, models indicate an MCS will develop to our WNW and push ESE into our region during the day on Wed. Again wind shear looks unimpressive but CAPE values have the potential to soar quite high again if we can get enough breaks in the clouds Wed morning. Thus, we could again see strong storms Wed as well. Thursday - Saturday... For Thursday and Friday, the ridge will start to break down over the Ohio Valley allowing the active westerly flow to sink into our region. This type of flow will feature multiple hard to time shortwaves which will cause showers/storms. Have limited POPs to 20-50% in the long term period due to lack of confidence in timing. Better forcing for storms may be present for next weekend if a more significant shortwave trough can develop as some models suggest. Temperatures/humidity should generally be on the decline through the weekend. While highs on Thurs should still be in the upper 80s/lower 90s, dewpts should be slightly lower resulting in heat indices below 100. By Saturday, high temps should fall back into the low to mid 80s. && .AVIATION (12Z TAF Update)... Updated at 641 AM EDT Sun Jun 21 2015 A front will approach the region today from the north. This will bring a chance for scattered showers and storms to SDF and LEX this afternoon. Have left VCTS out of BWG at this time due to more uncertainty in the chances for thunderstorms there. However, it will be monitored closely. Winds today will pick up through the morning and become gusty out of the WSW during the day. Storms and winds will be decreasing this evening with quiet conditions and light winds out of the WSW through the overnight hours. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....EER Long Term......AMS Aviation.......EER
AREA FORECAST DISCUSSION
NWS JACKSON KY
647 AM EDT SUN JUN 21 2015 .UPDATE... ISSUED AT 647 AM EDT SUN JUN 21 2015 THUNDERSTORM COMPLEX DISSIPATED BEFORE IT WAS ABLE TO MOVE INTO OUR NORTHWEST COUNTIES SO WILL REMOVE ANY MENTION OF RAIN UNTIL LATER THIS MORNING. NO OTHER CHANGES NEEDED AT THIS TIME. && .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 TODAY/S FORECAST IS A BIT MORE COMPLICATED THAN I WOULD LIKE DUE TO UPSTREAM MCS AND THE EFFECT IT/S DEBRIS CLOUDS WILL HAVE ON POTENTIAL CONVECTIVE DEVELOPMENT LATER TODAY ACROSS OUR AREA. BASED ON RAW EXTRAPOLATION...THE LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY OVER INDIANA WILL BE ENTERING OUR NORTHWEST COUNTIES BY AROUND DAWN. I EXPECT THIS LINE TO WEAKEN BUT A SMALL POP WILL BE INCLUDED UP NORTH EARLY ON TO ACCOUNT FOR THIS ACTIVITY. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS WILL LINGER THROUGH THE MORNING OVER THE OHIO VALLEY AND THIS SHOULD LIMIT DESTABILIZATION EARLY ON IN THE DAY DRAWING INTO QUESTION THE DEVELOPMENT OF ANOTHER COMPLEX OF STORMS SHOWN TO TAKE PLACE SO QUICKLY IN THE 21/00Z NAM OVER INDIANA AND OHIO. RECENT HRRR AND 21/00Z HIRES NMM SEEM MORE REASONABLE IN HOLDING OFF ANY SHOWER AND THUNDERSTORM DEVELOPMENT UNTIL LATER IN THE AFTERNOON. IT IS AT THIS TIME THAT AT LEAST SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER EASTERN KENTUCKY...AND THEY COULD BECOME QUITE STRONG AS THEY HAVE A RICH FUEL SOURCE OF LOW 70 DEGREE SURFACE DEWPOINTS TO TAP INTO. SPC CONTINUES TO HIGHLIGHT A GOOD CHUNK OF THE AREA IN A SLIGHT RISK AND WILL CONTINUE TO MENTION THIS IN OUR LOCAL HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS THAT DEVELOP THIS AFTERNOON WILL SETTLE SOUTHEAST AND WEAKEN DURING THE EVENING. LEFT OVER BOUNDARIES MAY THEN BE THE FOCUS FOR ADDITIONAL THUNDERSTORM ACTIVITY ON MONDAY AFTERNOON...BUT THESE SHOULD REMAIN WIDELY SCATTERED AS AN UPPER LEVEL RIDGE STARTS TO BUILD IN FROM THE WEST. HEAT AND HUMIDITY WILL BE ANOTHER CONCERN DURING THE SHORT TERM. CLOUD COVER EARLY IN THE DAY TODAY SHOULD SLOW OUR RISE A BIT...BUT STILL EXPECT TEMPS TO REACH AROUND 90 BY AFTERNOON AND THEN AGAIN MONDAY AFTERNOON. WITH DEWPOINTS PROGGED TO RISE INTO THE LOWER 70S FOR MOST LOCATIONS...AFTERNOON HEAT INDEX VALUES WILL RISE INTO THE MID TO UPPER 90S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE PERIOD. AN UPPER LEVEL RIDGE WILL START OUT ACROSS THE SOUTHERN PLAINS AND MISSISSIPPI VALLEY. THIS RIDGE WILL GRADUALLY WEAKEN AND GET DIRECTED TOWARD THE EAST...AS TRAVERSING NORTHERN STREAM SHORT WAVE ENERGY PROVIDES GLANCING BLOWS THROUGH EARLY NEXT WEEK. TOWARDS THE MIDDLE AND ESPECIALLY THE END OF NEXT WEEK...THE RIDGE WILL RE-ESTABLISH ITSELF ACROSS THE DESERT SOUTHWEST...ALLOWING FOR MORE TROUGHING TO RESIDE ACROSS THE MISSISSIPPI VALLEY. FOR EASTERN KENTUCKY...THIS WILL TRANSLATE INTO PLENTY OF HEAT AND HUMIDITY EARLY ON...ALONG WITH THE DAILY THREAT OF THUNDERSTORMS...MOST LIKELY PEAKING WITHIN THE NORMAL DIURNAL REGIME...ALTHOUGH AS MENTIONED PREVIOUSLY...LARGER THUNDERSTORM COMPLEX ACTIVITY WILL ALSO PLAY A ROLE. HIGHS WILL PEAK IN THE LOW 90S FOR MOST LOCATIONS THROUGH TUESDAY...BEFORE TAKING A BIT OF A HIT AS A SHEARED OUT COLD FRONT ATTEMPTS TO MOVE IN FROM THE NORTHWEST. HIGHS WILL DROP BACK INTO MAINLY THE 80S FOR THE SECOND HALF OF THE WORKWEEK...WITH SOME RELIEF FROM THE HUMIDITY BY THE START OF NEXT WEEKEND. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 647 AM EDT SUN JUN 21 2015 PATCHY MVFR CLOUDS AND FOG WILL SLOWLY GIVE WAY TO VFR CONDITIONS OVER THE NEXT HOUR OR TWO. A HOT AND HUMID DAY IS EXPECTED WITH SCATTERED THUNDERSTORMS DEVELOPING DURING THE AFTERNOON. ANY THUNDERSTORM THAT DEVELOPS WILL POTENTIALLY BECOME SEVERE WITH DAMAGING WINDS AND HAIL POSSIBLE. STORMS ARE EXPECTED TO DIMINISH DURING THE EVENING HOURS...FOLLOWED BY THE DEVELOPMENT OF PATCHY VALLEY FOG OVERNIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...ABE SHORT TERM...ABE LONG TERM...GEOGERIAN AVIATION...ABE
AREA FORECAST DISCUSSION
NWS JACKSON KY
330 AM EDT SUN JUN 21 2015 .SHORT TERM...(TODAY THROUGH MONDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 TODAY/S FORECAST IS A BIT MORE COMPLICATED THAN I WOULD LIKE DUE TO UPSTREAM MCS AND THE EFFECT IT/S DEBRIS CLOUDS WILL HAVE ON POTENTIAL CONVECTIVE DEVELOPMENT LATER TODAY ACROSS OUR AREA. BASED ON RAW EXTRAPOLATION...THE LINE OF SHOWERS AND THUNDERSTORMS CURRENTLY OVER INDIANA WILL BE ENTERING OUR NORTHWEST COUNTIES BY AROUND DAWN. I EXPECT THIS LINE TO WEAKEN BUT A SMALL POP WILL BE INCLUDED UP NORTH EARLY ON TO ACCOUNT FOR THIS ACTIVITY. CONSIDERABLE MID AND HIGH LEVEL CLOUDINESS WILL LINGER THROUGH THE MORNING OVER THE OHIO VALLEY AND THIS SHOULD LIMIT DESTABILIZATION EARLY ON IN THE DAY DRAWING INTO QUESTION THE DEVELOPMENT OF ANOTHER COMPLEX OF STORMS SHOWN TO TAKE PLACE SO QUICKLY IN THE 21/00Z NAM OVER INDIANA AND OHIO. RECENT HRRR AND 21/00Z HIRES NMM SEEM MORE REASONABLE IN HOLDING OFF ANY SHOWER AND THUNDERSTORM DEVELOPMENT UNTIL LATER IN THE AFTERNOON. IT IS AT THIS TIME THAT AT LEAST SCATTERED THUNDERSTORMS WILL LIKELY DEVELOP OVER EASTERN KENTUCKY...AND THEY COULD BECOME QUITE STRONG AS THEY HAVE A RICH FUEL SOURCE OF LOW 70 DEGREE SURFACE DEWPOINTS TO TAP INTO. SPC CONTINUES TO HIGHLIGHT A GOOD CHUNK OF THE AREA IN A SLIGHT RISK AND WILL CONTINUE TO MENTION THIS IN OUR LOCAL HAZARDOUS WEATHER OUTLOOK. THUNDERSTORMS THAT DEVELOP THIS AFTERNOON WILL SETTLE SOUTHEAST AND WEAKEN DURING THE EVENING. LEFT OVER BOUNDARIES MAY THEN BE THE FOCUS FOR ADDITIONAL THUNDERSTORM ACTIVITY ON MONDAY AFTERNOON...BUT THESE SHOULD REMAIN WIDELY SCATTERED AS AN UPPER LEVEL RIDGE STARTS TO BUILD IN FROM THE WEST. HEAT AND HUMIDITY WILL BE ANOTHER CONCERN DURING THE SHORT TERM. CLOUD COVER EARLY IN THE DAY TODAY SHOULD SLOW OUR RISE A BIT...BUT STILL EXPECT TEMPS TO REACH AROUND 90 BY AFTERNOON AND THEN AGAIN MONDAY AFTERNOON. WITH DEWPOINTS PROGGED TO RISE INTO THE LOWER 70S FOR MOST LOCATIONS...AFTERNOON HEAT INDEX VALUES WILL RISE INTO THE MID TO UPPER 90S. .LONG TERM...(MONDAY NIGHT THROUGH SATURDAY) ISSUED AT 330 AM EDT SUN JUN 21 2015 THE MODELS ARE GENERALLY IN GOOD AGREEMENT WITH THE LONG WAVE PATTERN THROUGH THE PERIOD. AN UPPER LEVEL RIDGE WILL START OUT ACROSS THE SOUTHERN PLAINS AND MISSISSIPPI VALLEY. THIS RIDGE WILL GRADUALLY WEAKEN AND GET DIRECTED TOWARD THE EAST...AS TRAVERSING NORTHERN STREAM SHORT WAVE ENERGY PROVIDES GLANCING BLOWS THROUGH EARLY NEXT WEEK. TOWARDS THE MIDDLE AND ESPECIALLY THE END OF NEXT WEEK...THE RIDGE WILL RE-ESTABLISH ITSELF ACROSS THE DESERT SOUTHWEST...ALLOWING FOR MORE TROUGHING TO RESIDE ACROSS THE MISSISSIPPI VALLEY. FOR EASTERN KENTUCKY...THIS WILL TRANSLATE INTO PLENTY OF HEAT AND HUMIDITY EARLY ON...ALONG WITH THE DAILY THREAT OF THUNDERSTORMS...MOST LIKELY PEAKING WITHIN THE NORMAL DIURNAL REGIME...ALTHOUGH AS MENTIONED PREVIOUSLY...LARGER THUNDERSTORM COMPLEX ACTIVITY WILL ALSO PLAY A ROLE. HIGHS WILL PEAK IN THE LOW 90S FOR MOST LOCATIONS THROUGH TUESDAY...BEFORE TAKING A BIT OF A HIT AS A SHEARED OUT COLD FRONT ATTEMPTS TO MOVE IN FROM THE NORTHWEST. HIGHS WILL DROP BACK INTO MAINLY THE 80S FOR THE SECOND HALF OF THE WORKWEEK...WITH SOME RELIEF FROM THE HUMIDITY BY THE START OF NEXT WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY EVENING) ISSUED AT 142 AM EDT SUN JUN 21 2015 PATCHY DENSE FOG HAS BEGUN TO FORM NOW THAT CLOUDS ARE SCATTERING OUT. HOWEVER...MID AND HIGH LEVEL CLOUDS WILL BE STREAMING IN QUICKLY FROM AN UPSTREAM THUNDERSTORM COMPLEX. THIS SHOULD ACT TO LIMIT THE FOG DEVELOPMENT AND LIKELY CAUSE IMPROVING CONDITIONS WHERE FOG HAS ALREADY SET UP. OTHERWISE...A WARM AND HUMID DAY IS ON THE WAY FOR SUNDAY. THERE REMAINS A POSSIBILITY FOR THUNDERSTORM DEVELOPMENT DURING THE AFTERNOON AND EVENING HOURS BUT TOO MUCH UNCERTAINTY EXISTS AT THIS TIME FOR MORE THAN A VCTS/CB MENTION IN THE TAFS. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...ABE LONG TERM...GEOGERIAN AVIATION...ABE
AREA FORECAST DISCUSSION
NWS LAKE CHARLES LA
104 PM CDT SUN JUN 21 2015 .AVIATION...RADARS ARE QUIET FOR NOW, SOME ENHANCED CU NOTED AROUND BPT, LCH, AND AEX. EXPECT THE CU TO DEVELOP AROUND AEX SHORTLY PER LATEST HRRR BUT WILL ONLY GO AS FAR AS VCTS. BPT HAS SOME MVFR CU CIGS WHICH SHOULD BE MOVING OUT SOON. WHILE MOISTURE AND SHORT WAVE ENERGY IS PRESENT, THERE APPEARS TO BE ENOUGH CAPPING TO INHIBIT CONVECTION SO I BACKED OFF MENTION OF TS FOR THE REMAINDER OF THE TERMINALS. SOME LIGHT FOG TO MVFR APPEARS POSSIBLE FOR AEX LATE TNITE. SWEENEY && .PREV DISCUSSION... /ISSUED 1138 AM CDT SUN JUN 21 2015/ DISCUSSION... CURRENT FORECAST IS ON TARGET...SO NO PLANS FOR AN UPDATE THIS MORNING. 13 PREV DISCUSSION... /ISSUED 632 AM CDT SUN JUN 21 2015/ AVIATION... FEW CLDS HOVERING AROUND 022 TO 028 THIS AM. CLOUDS BUILDING THRU THE MORNING INTO THE AFTERNOON HOURS. ISOLATED STORMS THIS AFTN THAT WILL SHUT DOWN AROUND SS. OTHERWISE LOOKING AT VFR CONDITIONS THROUGH THE DAY. PREV DISCUSSION... /ISSUED 255 AM CDT SUN JUN 21 2015/ DISCUSSION... WX MAP SHOWS THE REMNANTS OF BILL OVER E PA...LIFTING OUT WITH THE SHORTWAVE TROF. ACROSS OUR REGION...HIGH PRESSURE AT THE SFC CONTINUES ACROSS THE N GULF...WITH A WARM AND MOIST SOUTHERLY FLOW CONTINUING. LIKE THE LAST FEW DAYS...TEMPS THIS MORNING CONTINUE ABOVE NORMAL...RANGING FROM THE UPPER 70S/NEAR 80 ALONG AND S OF I-10 TO THE MID/UPPER 70S ELSEWHERE. A WEAK SHORTWAVE OVER TX...COMBINING WITH THE SEA-BREEZE FRONT... EXPECTED TO YIELD ISO-SCT AFTERNOON SHRA/TSRA ACROSS THE REGION. COVERAGE MAY BE A LITTLE ENHANCED OVER INLAND SE TX WHERE THE INTERACTION OF THE SHORTWAVE AND SEA-BREEZE FRONT OCCURS. OTHERWISE...HIGH PRESSURE AT THE SFC AND ALOFT WILL CONTINUE RIDGING WESTWARD OVER OUR REGION INTO EARLY THIS WEEK. THE FOCUS FOR ORGANIZED PRECIP WILL GRADUALLY DIMINISH BY MON/TUE...WITH DECREASED POPS AS WELL. WARMER THAN NORMAL TEMPS...ESPECIALLY FOR LOWS...WILL CONTINUE. BY WED & THU...A GRADUAL RETURN OF DEEP LAYER MOISTURE FROM THE EAST IS EXPECTED AS AN EASTERLY WAVE MOVES ACROSS THE REGION. THUS...POPS INCREASED DURING THIS PERIOD. BY FRI & SAT...MOISTURE AND FOCUS DIMINISHES SOMEWHAT AS RIDGING ALOFT RETURNS OVER THE N GULF. MARINE... A LIGHT ONSHORE FLOW CAN BE EXPECTED AS THE SUBTROPICAL HIGH CONTINUES RIDGING OVER THE GULF. RAIN CHANCES WILL REMAIN MINIMAL. && .PRELIMINARY POINT TEMPS/POPS... AEX 93 76 94 76 / 20 10 20 10 LCH 91 77 92 77 / 20 10 20 10 LFT 92 76 92 76 / 20 10 30 10 BPT 91 77 91 76 / 20 10 20 10 && .LCH WATCHES/WARNINGS/ADVISORIES... LA...NONE. TX...NONE. GM...NONE. && $$ AVIATION...11
AREA FORECAST DISCUSSION
NWS CARIBOU ME
610 AM EDT SUN JUN 21 2015 .SYNOPSIS... THE POST-TROPICAL REMAINS OF BILL WILL TRACK ACROSS THE GULF OF MAINE LATE THIS AFTERNOON AND MOVE INTO NOVA SCOTIA TONIGHT. WEAK HIGH PRESSURE BRIEFLY BUILDS BACK ACROSS THE REGION MONDAY. ANOTHER LOW PRESSURE PASSES NORTH OF THE AREA TUESDAY NIGHT. HIGH PRESSURE WILL BUILD TOWARD THE AREA AT THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... 610 AM UPDATE...RAIN ASSOCIATED WITH THE POST-TROPICAL REMAINS OF BILL ARE OVERSPREADING DOWNEAST AND CENTRAL MAINE EARLY THIS MORNING. THE RAIN WILL CONTINUE TO SPREAD TO THE NORTHEAST THIS MORNING. THE LATEST NEAR TERM MODEL RUNS OF THE HRRR AND RAP ARE JUST A BIT FURTHER TO THE NORTHWEST WITH THE RAIN LATER THIS MORNING INTO THE FIRST HALF OF THIS AFTERNOON. WILL MAKE SOME MINOR ADJUSTMENTS TO THE POPS/QPF FOR THE MORNING INTO THE EARLY AFTERNOON. PREVIOUS DISCUSSION...THE POST-TROPICAL REMAINS OF FORMER TROPICAL STORM BILL ARE EVIDENT ON SATELLITE PICTURES EARLY THIS MORNING ACROSS SOUTHERN PA. THE LOW WILL LIFT ACROSS THE TRI-STATE REGION LATE THIS MORNING...AND THEN ACROSS THE GULF OF MAINE LATE THIS AFTERNOON AND EARLY EVE. THE LOW CENTER IS EXPECTED TO BE ACROSS NORTHERN NOVA SCOTIA BY 12Z MON. THE REMAINS OF BILL WILL ABSORB MUCH OF THE ENERGY THAT APPROACHES FROM THE GREAT LAKES AND THE SOLUTIONS FROM ALL OF THE NEAR AND SHORT RANGE OPERATIONAL MODELS ARE MUCH MORE PROGRESSIVE THIS MORNING. RAIN WILL OVERSPREAD THE DOWNEAST REGION EARLY THIS MORNING WITH THE NORTHERN EDGE OF THE STEADY RAIN ABOUT AS FAR NORTH AS BAXTER STATE PARK AND HOULTON BY LATE MORNING. NORTH OF THIS AREA THERE WILL BE SOME SHOWERS BUT IT MAY REMAIN MOSTLY DRY IN THE ST JOHN VALLEY. THE RAIN WILL PULL EAST AS THE LOW EXITS THE AREA TONIGHT. MADE FAIRLY SIGNIFICANT ADJUSTMENTS TO THE QPF AND POPS THROUGH TONIGHT BASED ON THE MORE PROGRESSIVE SOLUTIONS. SOME OF THE RAIN TODAY WILL FALL HEAVILY AT TIMES DOWN EAST AND THERE MAY EVEN BE A FEW RUMBLES OF THUNDER WITH A BIT OF ELEVATED INSTABILITY. && .SHORT TERM /MONDAY THROUGH TUESDAY/... THE GFS...WHICH PERHAPS WAS SUFFERING FROM CNVCTV FEEDBACK ERRORS WITH ITS SOLUTION WITH A SEPARATE S/WV FROM THE UPPER GREAT LKS... HAS NOW COME IN LINE WITH THE OTHER 00Z DTMNSTC MODELS SUCH AS THE CANGEM...ECMWF...AND NAM WHICH NOW INDICATE THE LIONS SHARE OF RNFL TO BE OVR CNTRL AND DOWNEAST PTNS OF THE FA. THIS RESULTED IN A SIG LOWERING OF QPF AND POPS ACROSS THE NRN THIRD THIRD...AND SPCLY THE FAR N...WHERE LITTLE OR EVEN NO RNFL IS XPCTD. RATHER THEN USE WPC 6 HRLY QPF GRIDS...WE STAYED WITH A BLEND OF DTMNSTC MODEL 6 HRLY QPF THRU MON GIVEN THE NOW...UNIFORM TREND OF THE DTMNSTC MODELS SO CLOSE TO THIS PTN OF THE FCST. ANY REMAINING SHWRS SHOULD END MON EVE AS THE SFC LOW ASSOCIATED WITH THE REMNANTS OF BILL MOVE WELL E OVR THE OPEN N ATLC...AND A WEAK SFC HI PRES MOVES E TOWARD THE FA FROM QB. THIS SFC RIDGE QUICKLY MOVES E OF THE FA BY TUE MORN IN THE FAST WRLY FLOW REGIME ALF. THE NEXT S/WV FROM S CNTRL CAN THEN QUICKLY ADVCS TOWARD THE FA TUE AFTN FROM CNTRL QB. RNFL AMOUNTS LOOK TO RANGE FROM 0.15 TO 0.35 INCHES BY 00Z WED...WITH SOME ADDITIONAL LGT RNFL POSSIBLE TUE EVE AS AN UPPER TROF CROSSES THE FA. TYPICAL OF THE MODELS... THE GFS WAS ABOUT 3 TO 6 HRS FASTER WITH ONSET AND EXIT OF THIS SYSTEM...SO WE WENT WITH A MIDDLE GROUND OF TMG BETWEEN ALL OF THE FCST MODELS WITH THIS SYSTEM. POPS WERE AGAIN BUMPED UPWARDS TO A MAX OF CATEGORICAL. OTHERWISE...THE RECENT TREND OF COOL DYTM HI TEMPS AND NEAR SEASONAL OVRNGT LOWS WILL CONT MON THRU TUE. $$ .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... OTHERWISE WEAK S/WVS FROM CNTRL CAN WILL CONT TO MOVE ACROSS THE FA TUE NGT INTO SAT...DURG WHICH TM...AN UPPER LOW FROM LABRADOR DROPS SWRD OVR THE ERN MARITIMES. THIS WILL KEEP CONDITIONS UNSETTLED...SPCLY OVR NRN/ERN PTNS OF THE FA...WITH ISOLD TO WDLY SCT SHWRS FROM TM TO TM...SPCLY IN THE AFTN TO ERLY EVE HRS...WHEN LOW TO MID LVL INSTABILITY FROM DYTM HTG CAN BE XPCTD. BELOW NORMAL HI TEMPS AND NEAR TO JUST BLO NORMAL LOW TEMPS WILL CONT... WITH SOME WRMG POSSIBLE BY SAT. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... NEAR TERM: CONDITIONS WILL LOWER TO IFR AT THE DOWNEAST TERMINALS THIS MORNING WITH SOME IMPROVEMENT TO MVFR TONIGHT. AT THE NORTHERN TERMINALS CONDITIONS WILL LIKELY LOWER TO MVFR LATER THIS MORNING AND CONTINUE INTO TONIGHT. BRIEF PERIODS OF IFR ARE POSSIBLE LATE THIS MORNING AND EARLY THIS AFTERNOON. ISOLATED THUNDERSTORMS ARE POSSIBLE ACROSS DOWN EAST MAINE TODAY. SHORT TO LONG TERM: INITIALLY...MVFR CLGS AND BRIEF VSBYS XPCTD MOST TAF SITES MON WITH SC CLD CVR AND SHWRS...THEN IMPROVEMENT TO VFR XPCTD MON NGT...CONT INTO TUE MORN. CLDS AND VSBYS WILL THEN LOWER MVFR TUE AFTN ALL TAF SITE WITH THE ADVC OF SHWRS FROM THE W...LOWERING TO IFR TUE NGT. CONDITIONS THEN SLOWLY IMPROVE TO VFR ON WED...WITH NRN MOST TAF SITES TAKING LONGEST TO IMPROVE...PERHAPS AS LONG AS WED EVE. VFR SHOULD THEN PREVAIL OVER ALL SITES WED NGT THROUGH THU. && .MARINE... NEAR TERM: PUSHED BACK THE START TIME OF THE SMALL CRAFT ADVISORY BY A FEW HOURS AS THE WIND IS STILL LIGHT AND THE SEAS ONLY 1 TO 2 FEET ON THE COASTAL WATERS EARLY THIS MORNING. STILL EXPECT THE WIND AND SEAS TO INCREASE BY LATER THIS MORNING. SHORT TO LONG TERM: NO HDLNS XPCTD...XCPT FOR A BRIEF PD WITH A SRLY WIND FETCH TUE INTO TUE EVE WHERE WVS IN PARTICULAR COULD REACH SCA CRITERIA MSLY OVR OUR OUTER MZS. WENT WITH ABOUT 85 PERCENT OF WW3 WV GUIDANCE FOR FCST WV HTS FOR THESE PTNS OF THE CWF FCST. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...NONE. MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING FOR ANZ050>052. && $$ NEAR TERM...CB SHORT TERM...VJN LONG TERM...VJN AVIATION...CB/VJN MARINE...CB/VJN
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1006 AM EDT SUN JUN 21 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH THE REGION TODAY...MOVING THROUGH AND STALLING TO THE SOUTH OF THE AREA TONIGHT INTO MONDAY. THIS FRONT WILL LIFT NORTH LATE MONDAY...WITH THE NEXT COLD FRONT MOVING THROUGH ON TUESDAY. MULTIPLE DISTURBANCES WILL MOVE THROUGH THE REGION THE LATTER HALF OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... SUBSIDENCE IN THE WAKE OF LOW PRESSURE TO OUR EAST HAS RESULTED IN A GOOD BIT OF CLEARING. WESTERLY FLOW WILL PROMOTE THE DRYING TREND...ALTHOUGH VORT MAX WHICH REMAINS FROM AN OVERNIGHT MCS IS NOW OVER WVA. THE HRRR (AND TO A LESSER EXTENT SOME OTHER MODELS) DEVELOP SHOWERS AND STORMS EARLY THIS AFTERNOON IN ASSOCIATION WITH THIS...BUT NOT SURE IF THE ATMOSPHERE WILL BE CONDUCIVE. MAY MAKE SOME SLIGHT ADJUSTMENTS TO THE POP FORECAST BUT OTHERWISE THINK THE MORE SUBSTANTIAL CONVECTIVE RISK COMES MUCH LATER IN THE DAY WITH A NORTHERN STREAM SHORT WAVE AND COLD FRONT. THE BEST OVERLAP OF SHEAR...INSTBY AND FORCING IS TO OUR NW...BUT THERE WILL BE ENOUGH TO SUSTAIN SOME OF THE ACTIVITY INTO OUR AREA. A SLIGHT RISK FOR SEVERE WEATHER REMAINS DESIGNATED FOR AREAS WEST OF THE BLUE RIDGE. HIGH TEMPERATURES MAY NEED TO BE RAISED A BIT WITH A QUICK RISE INTO THE 80S SO FAR. PREVIOUS DISCUSSION... THE GENERAL TREND WITH THESE COLD FRONTS THE PAST COUPLE OF WEEKS HAS BEEN FOR THEIR WEAKENING/STALLING AS THEY REACH THE MID ATLANTIC AND THIS FRONT APPEARS TO BE FOLLOWING THE SAME PATTERN. ATTM THE FRONT MOVES THROUGH TONIGHT...THEN STALLS OVER SOUTHERN VA BY MONDAY MORNING. INSTABILITY WILL BE HIGHER HEADING EAST DURING THE DAY. HOWEVER...THE FRONT/SHORTWAVE ENERGY LOOK TO REACH AREAS FURTHER EAST AFTR PEAK HEATING...WITH INSTABILITY DCRSNG. WOULD LIKE TO HIGHLIGHT THAT ALL THE MODELS ARE SUGGESTING SCT TSTMS IN THE NORTHWESTERN HALF OF THE CWA...THEN WEAKENING...WITH THEN REDEVELOPMENT OVER SOUTHERN MD WHERE THE WLY FLOW INJECTS IN STEEPER MID LVL LAPSE RATES AND THE FRONTAL BOUNDARY NEARLY STALLS. THIS COULD BE OVERDONE A BIT...BUT SHOULD BE MONITORED. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... PCPN/CONVECTION TAPERS OFF BY 12Z MON MORNING...WITH A DRY PERIOD FOR THE FIRST HALF OF THE DAY. THE STALLED FRONT TO THE SOUTH WILL SLOWLY LIFT TO THE NORTH BY MON AFTN...WHICH COUPLED WITH A PASSING WEAK SHORTWAVE COULD ACT AS A TRIGGER FOR AFTN CONVECTION...MOSTLY FOR THE SOUTHERN AREAS CLOSER TO THE SFC BOUNDARY. ANYTHING THAT DOES FORM WILL TAPER OFF WITH LOSS OF DIURNAL HEATING MON EVENING...WITH DRY CONDITIONS THE LATTER HALF OF THE NIGHT. TUES MORNING REMAINS DRY...WITH INCRG POPS BY THE AFTN WITH AN UPPER LVL TROUGH AND SURFACE COLD FRONT APPROACHING THE REGION. THE NORTHERN EXTENT OF THE REGION HAS ALREADY BEEN PLACED IN A SLIGHT RISK...WITH THE MODELS HAVING BEEN HINTING AT THE SVR POTENTIAL NOW FOR A COUPLE OF DAYS. CONTINUING ABUNDANCE OF MOISTURE AND TEMPS WARMING INTO THE 90S YET AGAIN WILL LEAD TO A FAIRLY UNSTABLE AIRMASS. THIS COUPLED WITH SHEAR VALUES 30-40 KTS SHOULD LEAD TO SCT DEVELOPMENT OF STRONG TO SVR STORMS. HEAT INDICES MAY EXCEED 100 EAST OF THE BLUE RIDGE. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... WHILE MODELS BEGIN TO DIVERGE AFTER DAY 4...OVERALL PATTERN SUGGESTS TEMPS WILL BE CLOSER TO SEASONAL NORMS (HIGHS IN 80S...LOWS IN M/U60S)...WITH A SLIGHT COOLING TREND TOWARD WEEKS END. DIURNAL TSTM CHANCES WILL CONTINUE NEARLY EACH DAY IN WARM AND HUMID AIRMASS. EXCEPTION TO DIURNAL STORMS WOULD BE TSTM COMPLEXES THAT FORM TO OUR WEST AND MOVE OVER OUR AREA DURING THE OVERNIGHT IN NW FLOW. INTENSITY OF ANY TSTMS WILL DEPEND ON TIMING AND JUXTAPOSITION OF INSTABILITY WITH WIND FIELD...THINGS THAT ARE TOO DIFFICULT TO DISCERN THIS FAR OUT. HOWEVER...WE ARE IN OUR CLIMO PEAK SVR SEASON...AND WIND FIELD REMAINS MODERATE THROUGH THE WEEK...SO WILL NEED TO MONITOR. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... MAINLY VFR CONDITIONS THEN THE REMAINDER OF THE TAF PERIOD. WNW GUSTS TO 20 KT WILL BE POSSIBLE THROUGH AT LEAST EARLY AFTERNOON. SCT TSTMS PSBL THIS AFTN/EVENING...THOUGH MAINLY KMRB/KCHO/KIAD. SOME OF THE STORMS MAY BE STRONG TO EVEN SVR...WITH STRONG WINDS AND SOME HAIL. OUTSIDE OF THE STORMS...WINDS WILL BE WLY THIS REMAINING...BACKING TO THE SW BY THIS AFTN...ALL 12 KTS OR LESS. VFR CONDITIONS TUES THRU THE END OF THE WEEK. EACH AFTN HAS THE CHC FOR SHOWERS AND TSTMS...WITH EACH BRINGING THE CHC OF SUB-VFR CONDITIONS. && .MARINE... STRONG LOW LEVEL FLOW IN THE WAKE OF LOW PRESSURE MOVING EAST IS RESULTING IN WNW WIND GUSTS TO AROUND 20 KT. WHILE GRADIENT WEAKENS THROUGH THE DAY...MIXING MAY BE DEEP ENOUGH TO ALLOW OCCASIONAL GUSTS THROUGH LATE AFTERNOON. HAVE THEREFORE ISSUED A SCA FOR ALL WATERS THROUGH 6 PM. TSTMS PSBL THIS EVENING...BRINGING A PERIOD OF GUSTY WINDS. WINDS COULD BRIEFLY TOUCH SCA LEVELS MONDAY ON THE CHESAPEAKE BAY...BUT TOO LOW OF CONFIDENCE ATTM TO ISSUE A SCA. WINDS COULD BRIEFLY APPROACH SCA CRITERIA IN SOUTHWESTERLY FLOW TUE AND AGAIN WED. NO HAZARDS EXPECTED THU...EXCEPT IN ISO TSTM ACTIVITY. && .TIDES/COASTAL FLOODING... ADVISORY CONTINUES AT ANNAPOLIS UNTIL WATER LEVELS FALL LATER THIS MORNING. APPEARS BALTIMORE WILL BE CLOSE BUT MAY FALL JUST SHORT. WILL BE ASSESSING ALEXANDRIA AS HIGH TIDE WILL BE CLOSE. GOOD NW WINDS TODAY SHOULD TAKE THE PRESSURE OFF BY PUSHING A LITTLE OF THIS EXCESS OUT OF THE BAY. THEREFORE...NO ISSUES ANTICIPATED BYD THE UPCOMING TIDE CYCLE. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...NONE. MD...COASTAL FLOOD ADVISORY UNTIL 1 PM EDT THIS AFTERNOON FOR MDZ014. VA...NONE. WV...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ530>543. && $$ SYNOPSIS...SEARS NEAR TERM...SEARS/ADS SHORT TERM...SEARS LONG TERM...MSE AVIATION...SEARS MARINE...SEARS/ADS TIDES/COASTAL FLOODING...HTS/ADS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
720 PM EDT MON JUN 22 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 418 PM EDT MON JUN 22 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE TROUGH FROM NW ONTARIO INTO NRN MN. THE RESIDUAL MCV GENERATED FROM THE LARGE MCS EARLIER TODAY WAS LOCATED NEAR NW LOWER MI. FORCING ASSOCIATED WITH THIS FEATURE AND 305K-310K ISENTROPIC ASCENT AHEAD OF THE SHRTWV SUPPORTED SOME SHRA OVER NRN UPPER MI. AT THE SFC...A COLD FRONT EXTENDED ACROSS ERN MN. SCT SHRA AND ISOLATED TS HAS ALSO DEVELOPED ALONG AND AHEAD OF THE FRONT WHERE HEIGHT FALLS AHEAD OF THE SHRTWV WERE MOVING IN. CLOUDS AND AREAS OF SHOWERS HAVE LIMITED HEATING/INSTABILITY WITH HIGHEST SB/MU CAPE VALUES ONLY UP TO AROUND 500 J/KG OVER THE WEST. EXPECT SCT SHRA/TSRA TO CONTINUE TO PUSH FROM NW WI THROUGH UPPER MI THIS EVENING. ALTHOUGH 0-6KM/0-1KM SHEAR VALUES OF 40-60KT/25-35KT WOULD BE FAVORABLE FOR SOME STRONG/SVR STORMS. EVEN WITH SOME ADDITIONAL CAPE RECOVERY...THE MARGINAL INSTABILITY WILL LIMIT THE SVR POTENTIAL. NEVERTHELESS...AN ISOLATED SVR STORM CANNOT BE RULED OUT. THE SCT SHRA/TSRA ARE EXPECTED TO MOVE OUT OF THE CNTRL AND EAST BTWN 03Z-06Z WITH DRY WEATHER THE REST OF THE NIGHT. GUSTY WINDS WILL DEVELOP BEHIND THE FRONT AND LOW PRES WITH THE PRES RISE MAX MOVING THROUGH THIS EVENING AND A TIGHT PRES GRADIENT LINGERING OVERNIGHT. TUE...HIGH PRES BUILDING FROM THE UPPER MS VALLEY INTO THE WRN GREAT LAKES WITH MUCH DRIER AIR WILL BRING MOSTLY SUNNY SKIES...BREEZY NW WINDS AND TEMPS NEAR SEASONAL AVERAGES FROM THE LOWER TO MID 70S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 325 PM EDT MON JUN 22 2015 SEVERAL SHORTWAVES WILL AFFECT THE UPPER GREAT LAKES REGION THROUGH THE REST OF THE WORK WEEK AND INTO THE WEEKEND...WHICH WILL SLOWLY DEVELOP AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND. ONCE THE UPPER TROUGH BECOMES ESTABLISHED IN THE GREAT LAKES REGION...ECMWF/GFS ENSEMBLES ARE CONSISTENT ON THE UPPER RIDGE DEVELOPING OVER THE PACIFIC NORTHWEST THIS WEEKEND TO SLOWLY SHIFT TO THE NORTHWEST AND REMAIN IN PLACE THROUGH THE FIRST WEEK OF JULY. THAT WILL LEAD TO A PERSISTENT PERIOD OF NORMAL TO BELOW NORMAL TEMPERATURES FOR THE GREAT LAKES REGION. SHIFTING BACK TO THIS WEEK...THE FIRST WAVE THAT WILL AFFECT THE CWA WILL BE MOVING ACROSS FAR NORTHERN ONTARIO ON TUESDAY NIGHT...WITH SOUTHWESTERN EDGE OF THAT WAVE BRUSHING THE NORTHEAST PART OF LAKE SUPERIOR. AT THE SURFACE...A WEAK TROUGH WILL BE MOVING ACROSS THE LAKE AND EXPECT THERE TO BE SOME SHOWERS ALONG IT IN NORTHWEST ONTARIO ON TUESDAY AFTERNOON. BUT WITH THE LOSS OF DIURNAL HEATING...LIMITED MOISTURE...AND THE BEST FORCING STAYING WELL TO THE NORTHEAST OF THE CWA...WILL ONLY SHOW SLIGHT CHANCE POPS MOVING SOUTHEAST ACROSS NORTHEAST LAKE SUPERIOR. DID BRUSH THE KEWEENAW WITH THOSE SLIGHT CHANCE POPS WITH A DECENT NUMBER OF MODELS SHOWING A FEW HUNDREDTHS OF QPF. OTHERWISE...EXPECT THE REST OF THE AREA TO BE PARTLY CLOUDY TO MOSTLY CLEAR ON TUESDAY NIGHT DUE TO THE RESIDUAL EFFECTS OF THE SLOWLY DEPARTING SURFACE RIDGE. THAT SURFACE RIDGE WILL STILL BE OVER THE GREAT LAKES REGION ON WEDNESDAY MORNING...AS THE PARENT HIGH MOVES INTO THE MID ATLANTIC STATES. BUT THE NEXT SHORTWAVE WILL BE QUICKLY APPROACHING THE AREA ON WEDNESDAY AFTERNOON. MODELS CONTINUE TO DEPICT LINGERING MOISTURE ASSOCIATED WITH THE TUESDAY NIGHT SURFACE TROUGH BEING OVER THE U.P. ON WEDNESDAY AFTERNOON AND THAT WILL COMBINE WITH THE ARRIVAL OF ADDITIONAL MOISTURE/FORCING AND LAKE BREEZE DEVELOPMENT TO LEAD TO SHOWERS AND A FEW THUNDERSTORMS OVER PORTIONS OF WEST/CENTRAL UPPER MICHIGAN. WILL CONTINUE TO SHOW THE BEST CHANCE FOR SHOWERS OVER THE LAND AREAS AND INLAND FROM THE GREAT LAKES...WITH THE BEST OPPORTUNITY ALONG THE EXPECTED LAKE BREEZE FROM CENTRAL MARQUETTE COUNTY WESTWARD TOWARDS ONTONAGON COUNTY. WILL CONTINUE TO KEEP THUNDER VALUES IN THE SLIGHT CHANCE CATEGORY WITH MLCAPE VALUES GENERALLY UNDER 500J/KG (BEST INSTABILITY WELL TO THE SOUTH AND TIED TO THE STRONG STORMS LIKELY MOVING THROUGH SOUTHERN MINNESOTA/WISCONSIN LATE WEDNESDAY AFTERNOON/NIGHT). 0-6KM BULK SHEAR VALUES LOOK FAIRLY STRONG (APPROACHING 50KTS)...BUT LOOKING AT THE SOUNDINGS...THAT IS ALL TIED TO THE STRONG JET BETWEEN 5-6KM. THUS...THINK THE EFFECTIVE SHEAR VALUES AROUND 20KTS ARE MORE REASONABLE AND BELIEVE THE POTENTIAL FOR STRONG STORMS IS LIMITED AT THIS POINT. THE ONLY CONCERN WOULD BE WITH THE SLOW STORM MOTIONS LEADING TO LOCALIZED HEAVY RAIN WHERE THE THUNDERSTORMS OCCUR. WHILE THAT FIRST WAVE WILL AFFECT THE AREA WEDNESDAY AFTERNOON/EVENING...THERE ARE SEVERAL WEAK WAVES TRAILING IT THAT WILL HAVE AN INFLUENCE ON THE WEATHER FOR THE U.P. THROUGH THURSDAY NIGHT. WILL SHOW CHANCE POPS AS THESE DISTURBANCES MOVE THROUGH AND CONTINUE SLIGHT CHANCE FOR THUNDER (ALTHOUGH THAT APPEARS TO BE FAIRLY OPTIMISTIC). THOSE WAVES WILL AMPLIFY AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND AND LIKELY CONTINUE INTO EARLY JULY. THERE IS THE POTENTIAL FOR SOME DIURNAL SHOWERS THIS WEEKEND...ALTHOUGH THE SUBSIDENCE FROM A HIGH PRESSURE RIDGE MOVING THROUGH SHOULD LIMIT THE COVERAGE...BEFORE ANOTHER STRONGER WAVE DROPS SOUTHEAST ACROSS THE AREA ON MONDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 720 PM EDT MON JUN 22 2015RAPID CHANGE AT ALL SITES THIS EVENING AS A COLD FRONT MOVES QUICKLY THROUGH. CONDITIONS WILL BE MOSTLY VFR FOR THIS FORECAST PERIOD WITH BRIEF MVFR ALONG THE FRONT THIS EVENING AS SHOWERS MOVE THROUGH. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 418 PM EDT MON JUN 22 2015 A LOW PRES SYSTEM WIL MOVE EAST OF LAKE SUPERIOR TONIGHT. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING FROM 1 AM TO 10 AM EDT TUESDAY FOR LSZ251-266-267. LAKE MICHIGAN... DENSE FOG ADVISORY UNTIL MIDNIGHT EDT TONIGHT FOR LMZ221-248-250. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
438 PM EDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 437 PM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS. THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH WAS LOCATED FROM SRN ALBERTA INTO NW MONTANA. AT THE SFC...A WEAK RIDGE EXTENDED FROM WRN LAKE SUPERIOR INTO WI. THE MAIN FRONTAL BOUNDARY WAS WELL TO THE SOUTH...EXTENDING FROM NRN KS TO CNTRL INDIANA. SATELLITE LOOP SHOWED CLEARING OVER THE WEST AND SOUTH WITH LINGERING CLOUDS OVER THE NORTH AND EAST. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. MON...THE MORE PLAUSIBLE HIGHER RES MODEL SCENARIO...SHOWS AN ONGOING MCS INTO SRN MN WILL SPREAD TO THE ESE TO SRN WI OR NRN IL ALONG OR NEAR THE MUCAPE GRADIENT. SO...HAVE BACKED OFF ON THE PCPN TIMING/POPS INTO WRN UPPER MI MON MORNING INTO EARLY AFTERNOON AS THE GFS AND ESPECIALLY THE NAM SEEM TOO AGGRESSIVE WITH THE PCPN. SEVERAL OF THE HIGH RES MODELS KEEP UPPER MI DRY THROUGH 18Z. SHOWERS AND SOME EMBEDDED TSRA MAY SPREAD INTO THE WEST HALF IN THE MORNING SUPPORTED INCREASING MOISTURE ADVECTION AND 305K-310K ISENTROPIC LIFT AHEAD OF THE TROUGH MOVING TOWARD THE UPPER MS VALLEY. HOWEVER...CONFIDENCE IN PCPN COVERAGE/TIMING IS LOW WITH UNCERTAINTY ON THE IMPACTS OF THE MCS TO THE SOUTH. IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL BE POSSIBLE AS THE SHORTWAVE AND SFC TROUGH APPROACH. LARGE 0-6KM/0-1KM SHEAR VALUE OF 50-60KT/30-40KT AND LARGE HELICITY VALUES WILL SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT MAY EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING WINDS...LARGE HAIL AND EVEN TORNADOS WOULD BE POSSIBLE. HOWEVER...THIS IS CONDITIONAL AS CONFIDENCE IN THE AMOUNT OF INSTABILITY THAT WILL DEVELOP IS LOW. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 259 PM EDT SUN JUN 21 2015 A POTENT SHORTWAVE WILL BE MOVING ACROSS THE GREAT LAKES REGION AT THE START OF THE LONG TERM PERIOD. A SURFACE LOW OF AROUND 1000MB WILL BE LOCATED OVER CENTRAL UPPER MICHIGAN AT THE START OF THE PERIOD AND IT WILL QUICKLY MOVE NORTH OF LAKE HURON BY 06Z AND CONTINUE TO THE NORTHEAST INTO QUEBEC BY 12Z TUESDAY. CONVECTION EARLIER IN THE DAY WILL DETERMINE THE EVOLUTION OF THE POPS FOR THE MONDAY NIGHT PERIOD...BUT WILL SHOW THE HIGHEST POPS OVER THE EASTERN CWA AHEAD OF THE SURFACE LOW AND WITH THE COLD FRONT MOVING EAST THROUGH THE AREA. BEHIND THESE FEATURES...A TRAILING SURFACE TROUGH TO THE NORTHWEST MAY LEAD TO A SECONDARY AREA OF SHOWERS UNDER THE WRAP AROUND NORTHWESTERLY FLOW DURING THE EVENING AND EARLY OVERNIGHT HOURS IN THE WESTERN CWA AND THEN OVER THE NORTH CENTRAL AND EAST LATE IN THE NIGHT INTO THE FIRST HALF OF TUESDAY MORNING. WILL JUST SHOW SLIGHT CHANCE WORDING FOR THOSE SHOWERS. GUSTY NORTHWESTERLY WINDS WILL DEVELOP ON THE BACK SIDE OF THE LOW...WITH GUSTS UP TO 30 KNOTS OVER LAKE SUPERIOR AND THE SHORELINE AREAS. WINDS JUST ABOVE THE SURFACE ARE IN THE 35-40KT RANGE ON ALL OF THE MODELS...WHILE THE OVER LAKE INSTABILITY IS STILL VERY LOW AS TEMPERATURES JUST ABOVE THE SURFACE ARE STILL AROUND 13-14C. BUT WITH DECENT PRESSURE FALLS BEHIND THE LOW ON EASTERN LAKE SUPERIOR...FEEL COMFORTABLE ENOUGH PUTTING IN SOME GALE FORCE GUSTS IN THAT AREA FOR LATE MONDAY NIGHT INTO TUESDAY MORNING. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE INTO UPPER MICHIGAN ON TUESDAY AND DIMINISH THE WINDS ACROSS THE AREA. OTHERWISE...EXPECT ANY LINGERING LOW CLOUDS OVER THE AREA TUESDAY MORNING TO DIMINISH BY THE AFTERNOON HOURS AND WITH AFTERNOON MIXING HIGHS SHOULD RISE TO NEAR NORMAL VALUES. A WEAK SURFACE TROUGH WILL DROP SOUTHEAST INTO THE AREA ON TUESDAY NIGHT. EXPECT SHOWERS TO BE OCCURRING OVER NORTHWESTERN ONTARIO WITH THE TROUGH...BUT THE LOSS OF DIURNAL HEATING AND THE MAIN SHORTWAVE FORCING AND MOISTURE BRUSHING NORTHEAST LAKE SUPERIOR WILL KEEP THE SHOWERS MAINLY OVER THAT PORTION OF THE LAKE. BEHIND THAT WAVE...THE AREA WILL BE BETWEEN SYSTEMS ON WEDNESDAY MORNING...AS THE NEXT SHORTWAVE APPROACHES FROM THE WEST. THIS WILL LEAD TO SHOWERS MOVING INTO OR DEVELOPING OVER WESTERN UPPER MICHIGAN LATER WEDNESDAY AFTERNOON AND CONTINUING INTO WEDNESDAY NIGHT. THERE ARE SOME HINTS OF WEAK INSTABILITY WITH THIS NEXT WAVE (EVEN WITH THE SHORTWAVE MOVING THROUGH AT A CLIMATOLOGICALLY POOR TIME)...SO WILL MENTION JUST A SLIGHT CHANCE OF THUNDER. THIS WAVE WILL CONTINUE TO PRODUCE THE POTENTIAL FOR SHOWERS/THUNDERSTORMS OVER THE AREA INTO THURSDAY. MODELS DIFFER ON HOW QUICKLY THE LAST OF THE EMBEDDED SHORTWAVES DEPARTS THE AREA ON THURSDAY NIGHT...SO WILL SLOWLY DIMINISH POPS DURING THAT PERIOD. HIGH PRESSURE MOVES INTO THE AREA FOR FRIDAY...BUT COULD STILL SEE SOME DIURNAL SHOWERS OVER THE INTERIOR WEST/CENTRAL AND WILL HAVE SLIGHT CHANCE POPS DURING THE LATE MORNING AND AFTERNOON. MODELS CONTINUE TO SHOW THE FLOW TRANSITIONING TO NORTHWESTERLY ALOFT AS AN UPPER TROUGH DEVELOP OVER THE GREAT LAKES REGION. THIS MAY PUSH A FEW WEAK WAVES ACROSS THE AREA THIS WEEKEND...BUT RAIN POTENTIAL LOOKS TO BE LIMITED AT THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 151 PM EDT SUN JUN 21 2015 EXPECT DRIER AIR AND INCREASED HEATING/MIXING WILL SPREAD EAST THIS AFTERNOON WITH VLIFR CIGS AT CMX AND MVFR CIGS AT SAW IMPROVING TO VFR BY MID TO LATE AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED TO LINGER AT SAW FOR SOME FOG AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW. IFR IFR/VLIFR CONDITIONS DEVELOP THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE MORNING. SHOWERS AHEAD OF AN ADVANCING DISTURBANCE MAY AFFECT IWD BY THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 437 PM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TONIGHT INTO MONDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
436 PM EDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 433 PM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS. THE NEXT SIGNIFICANT UPSTREAM SHORTWAVE TROUGH WAS LOCATED FROM SRN ALBERTA INTO NW MONTANA. AT THE SFC...A WEAK RIDGE EXTENDED FROM WRN LAKE SUPERIOR INTO WI. THE MAIN FRONTAL BOUNDARY WAS WELL TO THE SOUTH...EXTENDING FROM NRN KS TO CNTRL INDIANA. SATELLITE LOOP SHOWED CLEARING OVER THE WEST AND SOUTH WITH LINGERING CLOUDS OVER THE NORTH AND EAST. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. MON...THE MORE PLAUSIBLE SCENARIO SUPPORTED BY MOST OF THE HIGHER RES MODELS SHOWS AN ONGOING MCS INTO SRN MN WILL SPREAD TO THE ESE TO SRN WI OR NRN IL ALONG OR NEAR THE MUCAPE GRADIENT. SO...HAVE BACKED OFF ON THE PCPN TIMING/POPS INTO WRN UPPER MI MON MORNING INTO EARLY AFTERNOON AS THE GFS AND ESPECIALLY THE NAM SEEM TOO AGGRESSIVE WITH THE PCPN. IN FACT...SEVERAL OF THE HIGH RES MODELS KEEP UPPER MI DRY THROUGH 18Z. NEVERTHELESS...SHOWERS AND SOME EMBEDDED TSRA MAY SPREAD INTO THE WEST HALF IN THE MORNING SUPPORTED INCREASING MOISTURE ADVECTION AND 305K- 310K ISENTROPIC LIFT AHEAD OF THE TROUGH MOVING TOWARD THE UPPER MS VALLEY. HOWEVER...CONFIDENCE IN PCPN COVERAGE/TIMING IS LOW WITH UNCERTAINTY ON THE IMPACTS OF THE MCS TO THE SOUTH. IF ENOUGH CLEARING/HEATING DEVELOPS IN THE AFTERNOON BEHIND THE INITIAL BATCH OF CONVECTIVE DEBRIS OR LIGHT RAIN TO BOOST TEMPS TO THE MID 70S AND CAPES TO AROUND 1K J/KG...SEVERE TSRA WILL BE POSSIBLE. LARGE 0- 6KM/0-1KM SHEAR VALUE OF 50-60KT/30-40KT AND LARGE HELICITY VALUES WILL SUPPORT THE POTENTIAL FOR SUPERCELL DEVELOPMENT THAT MAY EVOLVE/ORGANIZE INTO SEVERE STORM CLUSTERS OR AN MCS. DAMAGING WINDS...LARGE HAIL AND EVEN TORNADOS WOULD BE POSSIBLE. HOWEVER...THIS IS HIGHLY CONDITIONAL AS CONFIDENCE IN THE AMOUNT OF INSTABILITY THAT WILL DEVELOP IS LOW. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 259 PM EDT SUN JUN 21 2015 A POTENT SHORTWAVE WILL BE MOVING ACROSS THE GREAT LAKES REGION AT THE START OF THE LONG TERM PERIOD. A SURFACE LOW OF AROUND 1000MB WILL BE LOCATED OVER CENTRAL UPPER MICHIGAN AT THE START OF THE PERIOD AND IT WILL QUICKLY MOVE NORTH OF LAKE HURON BY 06Z AND CONTINUE TO THE NORTHEAST INTO QUEBEC BY 12Z TUESDAY. CONVECTION EARLIER IN THE DAY WILL DETERMINE THE EVOLUTION OF THE POPS FOR THE MONDAY NIGHT PERIOD...BUT WILL SHOW THE HIGHEST POPS OVER THE EASTERN CWA AHEAD OF THE SURFACE LOW AND WITH THE COLD FRONT MOVING EAST THROUGH THE AREA. BEHIND THESE FEATURES...A TRAILING SURFACE TROUGH TO THE NORTHWEST MAY LEAD TO A SECONDARY AREA OF SHOWERS UNDER THE WRAP AROUND NORTHWESTERLY FLOW DURING THE EVENING AND EARLY OVERNIGHT HOURS IN THE WESTERN CWA AND THEN OVER THE NORTH CENTRAL AND EAST LATE IN THE NIGHT INTO THE FIRST HALF OF TUESDAY MORNING. WILL JUST SHOW SLIGHT CHANCE WORDING FOR THOSE SHOWERS. GUSTY NORTHWESTERLY WINDS WILL DEVELOP ON THE BACK SIDE OF THE LOW...WITH GUSTS UP TO 30 KNOTS OVER LAKE SUPERIOR AND THE SHORELINE AREAS. WINDS JUST ABOVE THE SURFACE ARE IN THE 35-40KT RANGE ON ALL OF THE MODELS...WHILE THE OVER LAKE INSTABILITY IS STILL VERY LOW AS TEMPERATURES JUST ABOVE THE SURFACE ARE STILL AROUND 13-14C. BUT WITH DECENT PRESSURE FALLS BEHIND THE LOW ON EASTERN LAKE SUPERIOR...FEEL COMFORTABLE ENOUGH PUTTING IN SOME GALE FORCE GUSTS IN THAT AREA FOR LATE MONDAY NIGHT INTO TUESDAY MORNING. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE INTO UPPER MICHIGAN ON TUESDAY AND DIMINISH THE WINDS ACROSS THE AREA. OTHERWISE...EXPECT ANY LINGERING LOW CLOUDS OVER THE AREA TUESDAY MORNING TO DIMINISH BY THE AFTERNOON HOURS AND WITH AFTERNOON MIXING HIGHS SHOULD RISE TO NEAR NORMAL VALUES. A WEAK SURFACE TROUGH WILL DROP SOUTHEAST INTO THE AREA ON TUESDAY NIGHT. EXPECT SHOWERS TO BE OCCURRING OVER NORTHWESTERN ONTARIO WITH THE TROUGH...BUT THE LOSS OF DIURNAL HEATING AND THE MAIN SHORTWAVE FORCING AND MOISTURE BRUSHING NORTHEAST LAKE SUPERIOR WILL KEEP THE SHOWERS MAINLY OVER THAT PORTION OF THE LAKE. BEHIND THAT WAVE...THE AREA WILL BE BETWEEN SYSTEMS ON WEDNESDAY MORNING...AS THE NEXT SHORTWAVE APPROACHES FROM THE WEST. THIS WILL LEAD TO SHOWERS MOVING INTO OR DEVELOPING OVER WESTERN UPPER MICHIGAN LATER WEDNESDAY AFTERNOON AND CONTINUING INTO WEDNESDAY NIGHT. THERE ARE SOME HINTS OF WEAK INSTABILITY WITH THIS NEXT WAVE (EVEN WITH THE SHORTWAVE MOVING THROUGH AT A CLIMATOLOGICALLY POOR TIME)...SO WILL MENTION JUST A SLIGHT CHANCE OF THUNDER. THIS WAVE WILL CONTINUE TO PRODUCE THE POTENTIAL FOR SHOWERS/THUNDERSTORMS OVER THE AREA INTO THURSDAY. MODELS DIFFER ON HOW QUICKLY THE LAST OF THE EMBEDDED SHORTWAVES DEPARTS THE AREA ON THURSDAY NIGHT...SO WILL SLOWLY DIMINISH POPS DURING THAT PERIOD. HIGH PRESSURE MOVES INTO THE AREA FOR FRIDAY...BUT COULD STILL SEE SOME DIURNAL SHOWERS OVER THE INTERIOR WEST/CENTRAL AND WILL HAVE SLIGHT CHANCE POPS DURING THE LATE MORNING AND AFTERNOON. MODELS CONTINUE TO SHOW THE FLOW TRANSITIONING TO NORTHWESTERLY ALOFT AS AN UPPER TROUGH DEVELOP OVER THE GREAT LAKES REGION. THIS MAY PUSH A FEW WEAK WAVES ACROSS THE AREA THIS WEEKEND...BUT RAIN POTENTIAL LOOKS TO BE LIMITED AT THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 151 PM EDT SUN JUN 21 2015 EXPECT DRIER AIR AND INCREASED HEATING/MIXING WILL SPREAD EAST THIS AFTERNOON WITH VLIFR CIGS AT CMX AND MVFR CIGS AT SAW IMPROVING TO VFR BY MID TO LATE AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED TO LINGER AT SAW FOR SOME FOG AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW. IFR IFR/VLIFR CONDITIONS DEVELOP THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE MORNING. SHOWERS AHEAD OF AN ADVANCING DISTURBANCE MAY AFFECT IWD BY THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 449 AM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TODAY AND TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT WNW WINDS 20 TO 30 KTS MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TODAY INTO MONDAY EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
300 PM EDT SUN JUN 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 449 AM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE NOTED UPSTREAM OVER THE NRN MN. LINGERING LOW LEVEL MOISTURE ACROSS THE AREA HAS RESULTED IN THE DEVELOPMENT OF PATCHY FOG THIS MORNING. TODAY...WEAK SFC RIDGING BUILDING OVER THE AREA WILL ALLOW LAKE BREEZES TO DEVELOP BY AFTERNOON. AT SAME TIME MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB NEAR 500 J/KG OVER MAINLY THE SCNTRL FCST AREA FROM NEAR ESC TO CRYSTAL FALLS. THIS INSTABILITY ALONG WITH THE FOCUS PROVIDED BY THE LAKE BREEZE BOUNDARIES MAY BE ENOUGH TO TRIGGER SOME ISOLD SHRA/TSRA OVER THE SCNTRL FCST AREA...ESPECIALLY WITH MODELS SHOWING HINT OF A SHORTWAVE MOVING THROUGH THE AREA LATE MORNING/EARLY AFTERNOON. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. LOOK FOR HIGH TEMPS RANGING FROM THE MID TO UPPER 60S NORTH AND EAST TO THE LOWER 70S ALONG THE WISCONSIN BORDER COUNTIES. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY THROUGH MUCH OF THE NIGHT. INCREASING Q-VECT CONVERGENCE AND DEEP LAYER MOISTURE AHEAD OF A STRONG SHORTWAVE APPROACHING FROM THE NORTHERN PLAINS WILL BRING IN A CHANCE OF SHRA/TSRA TO THE FAR WESTERN CWA TOWARD 12Z MONDAY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 259 PM EDT SUN JUN 21 2015 A POTENT SHORTWAVE WILL BE MOVING ACROSS THE GREAT LAKES REGION AT THE START OF THE LONG TERM PERIOD. A SURFACE LOW OF AROUND 1000MB WILL BE LOCATED OVER CENTRAL UPPER MICHIGAN AT THE START OF THE PERIOD AND IT WILL QUICKLY MOVE NORTH OF LAKE HURON BY 06Z AND CONTINUE TO THE NORTHEAST INTO QUEBEC BY 12Z TUESDAY. CONVECTION EARLIER IN THE DAY WILL DETERMINE THE EVOLUTION OF THE POPS FOR THE MONDAY NIGHT PERIOD...BUT WILL SHOW THE HIGHEST POPS OVER THE EASTERN CWA AHEAD OF THE SURFACE LOW AND WITH THE COLD FRONT MOVING EAST THROUGH THE AREA. BEHIND THESE FEATURES...A TRAILING SURFACE TROUGH TO THE NORTHWEST MAY LEAD TO A SECONDARY AREA OF SHOWERS UNDER THE WRAP AROUND NORTHWESTERLY FLOW DURING THE EVENING AND EARLY OVERNIGHT HOURS IN THE WESTERN CWA AND THEN OVER THE NORTH CENTRAL AND EAST LATE IN THE NIGHT INTO THE FIRST HALF OF TUESDAY MORNING. WILL JUST SHOW SLIGHT CHANCE WORDING FOR THOSE SHOWERS. GUSTY NORTHWESTERLY WINDS WILL DEVELOP ON THE BACK SIDE OF THE LOW...WITH GUSTS UP TO 30 KNOTS OVER LAKE SUPERIOR AND THE SHORELINE AREAS. WINDS JUST ABOVE THE SURFACE ARE IN THE 35-40KT RANGE ON ALL OF THE MODELS...WHILE THE OVER LAKE INSTABILITY IS STILL VERY LOW AS TEMPERATURES JUST ABOVE THE SURFACE ARE STILL AROUND 13-14C. BUT WITH DECENT PRESSURE FALLS BEHIND THE LOW ON EASTERN LAKE SUPERIOR...FEEL COMFORTABLE ENOUGH PUTTING IN SOME GALE FORCE GUSTS IN THAT AREA FOR LATE MONDAY NIGHT INTO TUESDAY MORNING. A HIGH PRESSURE RIDGE WILL QUICKLY MOVE INTO UPPER MICHIGAN ON TUESDAY AND DIMINISH THE WINDS ACROSS THE AREA. OTHERWISE...EXPECT ANY LINGERING LOW CLOUDS OVER THE AREA TUESDAY MORNING TO DIMINISH BY THE AFTERNOON HOURS AND WITH AFTERNOON MIXING HIGHS SHOULD RISE TO NEAR NORMAL VALUES. A WEAK SURFACE TROUGH WILL DROP SOUTHEAST INTO THE AREA ON TUESDAY NIGHT. EXPECT SHOWERS TO BE OCCURRING OVER NORTHWESTERN ONTARIO WITH THE TROUGH...BUT THE LOSS OF DIURNAL HEATING AND THE MAIN SHORTWAVE FORCING AND MOISTURE BRUSHING NORTHEAST LAKE SUPERIOR WILL KEEP THE SHOWERS MAINLY OVER THAT PORTION OF THE LAKE. BEHIND THAT WAVE...THE AREA WILL BE BETWEEN SYSTEMS ON WEDNESDAY MORNING...AS THE NEXT SHORTWAVE APPROACHES FROM THE WEST. THIS WILL LEAD TO SHOWERS MOVING INTO OR DEVELOPING OVER WESTERN UPPER MICHIGAN LATER WEDNESDAY AFTERNOON AND CONTINUING INTO WEDNESDAY NIGHT. THERE ARE SOME HINTS OF WEAK INSTABILITY WITH THIS NEXT WAVE (EVEN WITH THE SHORTWAVE MOVING THROUGH AT A CLIMATOLOGICALLY POOR TIME)...SO WILL MENTION JUST A SLIGHT CHANCE OF THUNDER. THIS WAVE WILL CONTINUE TO PRODUCE THE POTENTIAL FOR SHOWERS/THUNDERSTORMS OVER THE AREA INTO THURSDAY. MODELS DIFFER ON HOW QUICKLY THE LAST OF THE EMBEDDED SHORTWAVES DEPARTS THE AREA ON THURSDAY NIGHT...SO WILL SLOWLY DIMINISH POPS DURING THAT PERIOD. HIGH PRESSURE MOVES INTO THE AREA FOR FRIDAY...BUT COULD STILL SEE SOME DIURNAL SHOWERS OVER THE INTERIOR WEST/CENTRAL AND WILL HAVE SLIGHT CHANCE POPS DURING THE LATE MORNING AND AFTERNOON. MODELS CONTINUE TO SHOW THE FLOW TRANSITIONING TO NORTHWESTERLY ALOFT AS AN UPPER TROUGH DEVELOP OVER THE GREAT LAKES REGION. THIS MAY PUSH A FEW WEAK WAVES ACROSS THE AREA THIS WEEKEND...BUT RAIN POTENTIAL LOOKS TO BE LIMITED AT THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 151 PM EDT SUN JUN 21 2015 EXPECT DRIER AIR AND INCREASED HEATING/MIXING WILL SPREAD EAST THIS AFTERNOON WITH VLIFR CIGS AT CMX AND MVFR CIGS AT SAW IMPROVING TO VFR BY MID TO LATE AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED TO LINGER AT SAW FOR SOME FOG AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW. IFR IFR/VLIFR CONDITIONS DEVELOP THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE MORNING. SHOWERS AHEAD OF AN ADVANCING DISTURBANCE MAY AFFECT IWD BY THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 449 AM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TODAY AND TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT WNW WINDS 20 TO 30 KTS MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TODAY INTO MONDAY EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
152 PM EDT SUN JUN 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 449 AM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE NOTED UPSTREAM OVER THE NRN MN. LINGERING LOW LEVEL MOISTURE ACROSS THE AREA HAS RESULTED IN THE DEVELOPMENT OF PATCHY FOG THIS MORNING. TODAY...WEAK SFC RIDGING BUILDING OVER THE AREA WILL ALLOW LAKE BREEZES TO DEVELOP BY AFTERNOON. AT SAME TIME MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB NEAR 500 J/KG OVER MAINLY THE SCNTRL FCST AREA FROM NEAR ESC TO CRYSTAL FALLS. THIS INSTABILITY ALONG WITH THE FOCUS PROVIDED BY THE LAKE BREEZE BOUNDARIES MAY BE ENOUGH TO TRIGGER SOME ISOLD SHRA/TSRA OVER THE SCNTRL FCST AREA...ESPECIALLY WITH MODELS SHOWING HINT OF A SHORTWAVE MOVING THROUGH THE AREA LATE MORNING/EARLY AFTERNOON. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. LOOK FOR HIGH TEMPS RANGING FROM THE MID TO UPPER 60S NORTH AND EAST TO THE LOWER 70S ALONG THE WISCONSIN BORDER COUNTIES. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY THROUGH MUCH OF THE NIGHT. INCREASING Q-VECT CONVERGENCE AND DEEP LAYER MOISTURE AHEAD OF A STRONG SHORTWAVE APPROACHING FROM THE NORTHERN PLAINS WILL BRING IN A CHANCE OF SHRA/TSRA TO THE FAR WESTERN CWA TOWARD 12Z MONDAY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 352 AM EDT SUN JUN 21 2015 MAIN FORECAST CONCERN IS THE SETUP FOR MON WHEN TWO WAVES (ONE W OF OR AND WA AND ANOTHER OVER BC CANADA) MERGE AND SEND A POTENT SHORTWAVE THROUGH THE REGION. WHILE THERE IS SOME DISAGREEMENT/VARIABILITY...MODELS GENERALLY INDICATE A LOW AROUND 1000MB MOVING FROM CENTRAL/SRN MN TO THE CENTRAL U.P. MON AFTERNOON/EVENING. THE WARM FRONT ASSOCIATED WITH THE SYSTEM LOOKS TO HANG UP OVER CENTRAL OR NRN WI...WHICH IS SUFFICIENT TO KEEP LIKELY/CATEGORICAL POPS OVER THE CWA. THE FORECAST FOR MON IS EXTREMELY DEPENDENT ON CONVECTION AND EXACTLY WHERE THE WARM FRONT SETS UP. MORNING CONVECTION WILL PLAY A ROLE IN THE COMPLICATION...WITH AN UNKNOWN LEVEL OF CLEARING/DESTABILIZATION. CURRENT THINKING CONTINUES TO BE THAT EITHER A STRONG CONVECTIVE COMPLEX OR CLUSTER OF SUPERCELL STORMS WILL MOVE S OF THE CWA IN THE AFTERNOON/EVENING. HOWEVER...IF THE FRONT SURGES FARTHER N OR IF ENOUGH INSTABILITY CAN DEVELOP...SHEAR WILL BE VERY STRONG AND THE OVERALL SYSTEM QUITE POTENT SO SEVERE STORMS WOULD LIKELY RESULT...WITH LARGE HAIL...DAMAGING WINDS AND TORNADOES ALL CONDITIONALLY POSSIBLE. IT SEEMS THAT SOME LOCATIONS IN THE WI/MI REGION (LIKELY FROM CENTRAL WI TO LOWER MI) WILL SEE A SIGNIFICANT SEVERE EVENT. AT THIS TIME WILL CONTINUE TO FAVOR A MORE CLIMATOLOGICAL APPROACH (WHICH IS SUPPORTED BY THE GFS/ECMWF/GEM) WHICH KEEP STRONGER STORMS S OF THE CWA AND WILL NOT PUT ANY STRONG/SEVERE EMPHASIS INTO THE HWO. SHOULD SEE GRADUALLY CLEARING CONDITIONS BY TUE MORNING WITH HIGH PRESSURE DOMINATING THE CENTRAL U.S.. SHOULD SEE MARINE FOG NEAR ERN LAKE SUPERIOR MON NIGHT AS NW WINDS BEHIND THE SHORTWAVE SWEEP FOG ONSHORE. OTHERWISE...SUNNY SKIES WILL PREVAIL ON TUE. NEXT CHANCE OF SHOWERS AND POSSIBLE SOME THUNDER ARRIVES ON WED AFTERNOON AND CONTINUES OFF AND ON THROUGH THU AS A SHORTWAVE MOVES THROUGH THE AREA. LIMITED THUNDER POTENTIAL TO SLIGHT CHANCES GIVEN LIMITED INSTABILITY. AN UPPER TROUGH LOOKS TO BECOME DOMINANT OVER THE GREAT LAKES REGION...WHICH WILL MAKE FOR COOLER CONDITIONS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 151 PM EDT SUN JUN 21 2015 EXPECT DRIER AIR AND INCREASED HEATING/MIXING WILL SPREAD EAST THIS AFTERNOON WITH VLIFR CIGS AT CMX AND MVFR CIGS AT SAW IMPROVING TO VFR BY MID TO LATE AFTERNOON. ENOUGH LOW LEVEL MOISTURE IS EXPECTED TO LINGER AT SAW FOR SOME FOG AND LOWER CIGS TO REDEVELOP OVERNIGHT AIDED BY WEAK SRLY FLOW. IFR IFR/VLIFR CONDITIONS DEVELOP THEY SHOULD AGAIN LIFT TO VFR BY MID TO LATE MORNING. SHOWERS AHEAD OF AN ADVANCING DISTURBANCE MAY AFFECT IWD BY THE END OF THE TAF PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 449 AM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TODAY AND TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT WNW WINDS 20 TO 30 KTS MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TODAY INTO MONDAY EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
746 AM EDT SUN JUN 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 449 AM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE NOTED UPSTREAM OVER THE NRN MN. LINGERING LOW LEVEL MOISTURE ACROSS THE AREA HAS RESULTED IN THE DEVELOPMENT OF PATCHY FOG THIS MORNING. TODAY...WEAK SFC RIDGING BUILDING OVER THE AREA WILL ALLOW LAKE BREEZES TO DEVELOP BY AFTERNOON. AT SAME TIME MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB NEAR 500 J/KG OVER MAINLY THE SCNTRL FCST AREA FROM NEAR ESC TO CRYSTAL FALLS. THIS INSTABILITY ALONG WITH THE FOCUS PROVIDED BY THE LAKE BREEZE BOUNDARIES MAY BE ENOUGH TO TRIGGER SOME ISOLD SHRA/TSRA OVER THE SCNTRL FCST AREA...ESPECIALLY WITH MODELS SHOWING HINT OF A SHORTWAVE MOVING THROUGH THE AREA LATE MORNING/EARLY AFTERNOON. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. LOOK FOR HIGH TEMPS RANGING FROM THE MID TO UPPER 60S NORTH AND EAST TO THE LOWER 70S ALONG THE WISCONSIN BORDER COUNTIES. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY THROUGH MUCH OF THE NIGHT. INCREASING Q-VECT CONVERGENCE AND DEEP LAYER MOISTURE AHEAD OF A STRONG SHORTWAVE APPROACHING FROM THE NORTHERN PLAINS WILL BRING IN A CHANCE OF SHRA/TSRA TO THE FAR WESTERN CWA TOWARD 12Z MONDAY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 352 AM EDT SUN JUN 21 2015 MAIN FORECAST CONCERN IS THE SETUP FOR MON WHEN TWO WAVES (ONE W OF OR AND WA AND ANOTHER OVER BC CANADA) MERGE AND SEND A POTENT SHORTWAVE THROUGH THE REGION. WHILE THERE IS SOME DISAGREEMENT/VARIABILITY...MODELS GENERALLY INDICATE A LOW AROUND 1000MB MOVING FROM CENTRAL/SRN MN TO THE CENTRAL U.P. MON AFTERNOON/EVENING. THE WARM FRONT ASSOCIATED WITH THE SYSTEM LOOKS TO HANG UP OVER CENTRAL OR NRN WI...WHICH IS SUFFICIENT TO KEEP LIKELY/CATEGORICAL POPS OVER THE CWA. THE FORECAST FOR MON IS EXTREMELY DEPENDENT ON CONVECTION AND EXACTLY WHERE THE WARM FRONT SETS UP. MORNING CONVECTION WILL PLAY A ROLE IN THE COMPLICATION...WITH AN UNKNOWN LEVEL OF CLEARING/DESTABILIZATION. CURRENT THINKING CONTINUES TO BE THAT EITHER A STRONG CONVECTIVE COMPLEX OR CLUSTER OF SUPERCELL STORMS WILL MOVE S OF THE CWA IN THE AFTERNOON/EVENING. HOWEVER...IF THE FRONT SURGES FARTHER N OR IF ENOUGH INSTABILITY CAN DEVELOP...SHEAR WILL BE VERY STRONG AND THE OVERALL SYSTEM QUITE POTENT SO SEVERE STORMS WOULD LIKELY RESULT...WITH LARGE HAIL...DAMAGING WINDS AND TORNADOES ALL CONDITIONALLY POSSIBLE. IT SEEMS THAT SOME LOCATIONS IN THE WI/MI REGION (LIKELY FROM CENTRAL WI TO LOWER MI) WILL SEE A SIGNIFICANT SEVERE EVENT. AT THIS TIME WILL CONTINUE TO FAVOR A MORE CLIMATOLOGICAL APPROACH (WHICH IS SUPPORTED BY THE GFS/ECMWF/GEM) WHICH KEEP STRONGER STORMS S OF THE CWA AND WILL NOT PUT ANY STRONG/SEVERE EMPHASIS INTO THE HWO. SHOULD SEE GRADUALLY CLEARING CONDITIONS BY TUE MORNING WITH HIGH PRESSURE DOMINATING THE CENTRAL U.S.. SHOULD SEE MARINE FOG NEAR ERN LAKE SUPERIOR MON NIGHT AS NW WINDS BEHIND THE SHORTWAVE SWEEP FOG ONSHORE. OTHERWISE...SUNNY SKIES WILL PREVAIL ON TUE. NEXT CHANCE OF SHOWERS AND POSSIBLE SOME THUNDER ARRIVES ON WED AFTERNOON AND CONTINUES OFF AND ON THROUGH THU AS A SHORTWAVE MOVES THROUGH THE AREA. LIMITED THUNDER POTENTIAL TO SLIGHT CHANCES GIVEN LIMITED INSTABILITY. AN UPPER TROUGH LOOKS TO BECOME DOMINANT OVER THE GREAT LAKES REGION...WHICH WILL MAKE FOR COOLER CONDITIONS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 735 AM EDT SUN JUN 21 2015 LINGERING LOW LEVEL MOISTURE WILL ALLOW VLIFR CONDITIONS TO PERSIST FOR A FEW MORE HOURS BEFORE DAYTIME HEATING ALLOWS IMPROVEMENT TO VFR BY LATE MORNING/EARLY AFTERNOON. LIFR CONDITIONS IN FOG/STRATUS COULD REDEVELOP AGAIN LATE TONIGHT UNDER A MOIST S-SE FLOW...ESPECIALLY AT KSAW WHERE CLEAR SKIES WILL ALLOW TEMPS TO DROP QUICKER TOWARD SATURATION. INCREASING MID-HIGH CLOUDS AHEAD OF APPROACHING SYSTEM OVER THE PLAINS MAY PRECLUDE FOG DEVELOPMENT AT KIWD AND KCMX SO KEPT FOG/STRATUS OUT OF FCST THERE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 449 AM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TODAY AND TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT WNW WINDS 20 TO 30 KTS MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TODAY INTO MONDAY EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
449 AM EDT SUN JUN 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 449 AM EDT SUN JUN 21 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE NOTED UPSTREAM OVER THE NRN MN. LINGERING LOW LEVEL MOISTURE ACROSS THE AREA HAS RESULTED IN THE DEVELOPMENT OF PATCHY FOG THIS MORNING. TODAY...WEAK SFC RIDGING BUILDING OVER THE AREA WILL ALLOW LAKE BREEZES TO DEVELOP BY AFTERNOON. AT SAME TIME MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB NEAR 500 J/KG OVER MAINLY THE SCNTRL FCST AREA FROM NEAR ESC TO CRYSTAL FALLS. THIS INSTABILITY ALONG WITH THE FOCUS PROVIDED BY THE LAKE BREEZE BOUNDARIES MAY BE ENOUGH TO TRIGGER SOME ISOLD SHRA/TSRA OVER THE SCNTRL FCST AREA...ESPECIALLY WITH MODELS SHOWING HINT OF A SHORTWAVE MOVING THROUGH THE AREA LATE MORNING/EARLY AFTERNOON. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. LOOK FOR HIGH TEMPS RANGING FROM THE MID TO UPPER 60S NORTH AND EAST TO THE LOWER 70S ALONG THE WISCONSIN BORDER COUNTIES. TONIGHT...MID-LVL RIDGING MOVING ACROSS THE AREA WILL KEEP THE FCST AREA DRY THROUGH MUCH OF THE NIGHT. INCREASING Q-VECT CONVERGENCE AND DEEP LAYER MOISTURE AHEAD OF A STRONG SHORTWAVE APPROACHING FROM THE NORTHERN PLAINS WILL BRING IN A CHANCE OF SHRA/TSRA TO THE FAR WESTERN CWA TOWARD 12Z MONDAY. HIGHER DEW POINTS IN THE UPPER 50S ADVECTING IN WITH A DEVELOPING SOUTHERLY FLOW AHEAD OF PLAINS SYSTEM WILL ALSO CONTRIBUTE TO MORE FOG/STRATUS FORMATION ACROSS MUCH OF THE CWA...ESPECIALLY LATE TONIGHT OVER THE EAST HALF OF UPPER MI...DOWNWIND OF LAKE MICHIGAN. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 352 AM EDT SUN JUN 21 2015 MAIN FORECAST CONCERN IS THE SETUP FOR MON WHEN TWO WAVES (ONE W OF OR AND WA AND ANOTHER OVER BC CANADA) MERGE AND SEND A POTENT SHORTWAVE THROUGH THE REGION. WHILE THERE IS SOME DISAGREEMENT/VARIABILITY...MODELS GENERALLY INDICATE A LOW AROUND 1000MB MOVING FROM CENTRAL/SRN MN TO THE CENTRAL U.P. MON AFTERNOON/EVENING. THE WARM FRONT ASSOCIATED WITH THE SYSTEM LOOKS TO HANG UP OVER CENTRAL OR NRN WI...WHICH IS SUFFICIENT TO KEEP LIKELY/CATEGORICAL POPS OVER THE CWA. THE FORECAST FOR MON IS EXTREMELY DEPENDENT ON CONVECTION AND EXACTLY WHERE THE WARM FRONT SETS UP. MORNING CONVECTION WILL PLAY A ROLE IN THE COMPLICATION...WITH AN UNKNOWN LEVEL OF CLEARING/DESTABILIZATION. CURRENT THINKING CONTINUES TO BE THAT EITHER A STRONG CONVECTIVE COMPLEX OR CLUSTER OF SUPERCELL STORMS WILL MOVE S OF THE CWA IN THE AFTERNOON/EVENING. HOWEVER...IF THE FRONT SURGES FARTHER N OR IF ENOUGH INSTABILITY CAN DEVELOP...SHEAR WILL BE VERY STRONG AND THE OVERALL SYSTEM QUITE POTENT SO SEVERE STORMS WOULD LIKELY RESULT...WITH LARGE HAIL...DAMAGING WINDS AND TORNADOES ALL CONDITIONALLY POSSIBLE. IT SEEMS THAT SOME LOCATIONS IN THE WI/MI REGION (LIKELY FROM CENTRAL WI TO LOWER MI) WILL SEE A SIGNIFICANT SEVERE EVENT. AT THIS TIME WILL CONTINUE TO FAVOR A MORE CLIMATOLOGICAL APPROACH (WHICH IS SUPPORTED BY THE GFS/ECMWF/GEM) WHICH KEEP STRONGER STORMS S OF THE CWA AND WILL NOT PUT ANY STRONG/SEVERE EMPHASIS INTO THE HWO. SHOULD SEE GRADUALLY CLEARING CONDITIONS BY TUE MORNING WITH HIGH PRESSURE DOMINATING THE CENTRAL U.S.. SHOULD SEE MARINE FOG NEAR ERN LAKE SUPERIOR MON NIGHT AS NW WINDS BEHIND THE SHORTWAVE SWEEP FOG ONSHORE. OTHERWISE...SUNNY SKIES WILL PREVAIL ON TUE. NEXT CHANCE OF SHOWERS AND POSSIBLE SOME THUNDER ARRIVES ON WED AFTERNOON AND CONTINUES OFF AND ON THROUGH THU AS A SHORTWAVE MOVES THROUGH THE AREA. LIMITED THUNDER POTENTIAL TO SLIGHT CHANCES GIVEN LIMITED INSTABILITY. AN UPPER TROUGH LOOKS TO BECOME DOMINANT OVER THE GREAT LAKES REGION...WHICH WILL MAKE FOR COOLER CONDITIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 127 AM EDT SUN JUN 21 2015 LOW LEVEL MOISTURE WILL REMAIN INTO SUNDAY AFTERNOON BEFORE DRIER AIR ARRIVES. UNTIL THEN...VLIFR CONDITIONS WILL BE EXPECTED AT ALL THE TAF SITES INTO SUN MORNING BEFORE A SLOW IMPROVEMENT TO VFR TAKES PLACE SUN AFTERNOON AND LASTS INTO SUN EVENING. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 449 AM EDT SUN JUN 21 2015 HIGH PRES OVER THE AREA TODAY AND TONIGHT WILL KEEP WINDS UNDER 20 KTS. A LOW PRES SYSTEM WILL THEN MOVE OVER THE UPPER GREAT LAKES MONDAY INTO MON EVENING. COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT WNW WINDS 20 TO 30 KTS MONDAY NIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO THU. LINGERING LOW-LVL MOISTURE WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE FROM TODAY INTO MONDAY EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...07 MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 AM EDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 420 PM EDT SAT JUN 20 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS. THE SHORTWAVE TROUGH THAT BROUGHT THE LARGE AREA OF RAIN THROUGH UPPER MI WAS EXITING THE AREA LEAVING MAINLY JUST PATCHY LIGHT RAIN OF DRIZZLE OVER THE NORTH AND EAST. ANOTHER TRAILING SHRTWV OVER NE MN SUPPORTED SCT SHRA FROM THE MN ARROWHEAD INTO WRN LAKE SUPERIOR. OTHER UPSTREAM SHORTWAVES WERE LOCATED OVER NRN ND AND SE SASK. TONIGHT...EXPECT ISOLD/SCT -SHRA INTO THE CWA THIS EVENING ASSOCIATED WITH THE MN SHRTWV THAT SHOULD DIMINISH AND END AFTER 03Z. OTHERWISE...WITH ABUNDANT LOW LEVEL MOISTURE OVER THE REGION...PATCHY FOG WILL SHOULD DEVELOP. NNW UPSLOPE 10-15 KNOT 950- 900 MB FLOW INTO N CNTRL UPPER MI MAY ALSO SUPPORT SOME DRIZZLE OVERNIGHT INTO EARLY SUNDAY. SUN...THERE MAY BE SOME ISOLATED LIGHT SHOWERS ASSOCIATED WITH THE SASK/ND SHRTWVS EARLY OVER THE NORTH. OTHERWISE...EXPECT A WEAK SFC RIDGE TO BUILD INTO THE AREA WITH MAINLY LIGHT WINDS ALLOWING LAKE BREEZES TO DEVELOP. MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB INTO THE 500-1000 J/KG RANGE OVER MAINLY THE SRN CWA FROM NEAR IMT- MNM. THIS MAY BE ENOUGH TO ALLOW SOME SHRA/TSRA TO DEVELOP...ESPECIALLY NEAR THE LAKE MI BREEZE BOUNDARY. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 352 AM EDT SUN JUN 21 2015 MAIN FORECAST CONCERN IS THE SETUP FOR MON WHEN TWO WAVES (ONE W OF OR AND WA AND ANOTHER OVER BC CANADA) MERGE AND SEND A POTENT SHORTWAVE THROUGH THE REGION. WHILE THERE IS SOME DISAGREEMENT/VARIABILITY...MODELS GENERALLY INDICATE A LOW AROUND 1000MB MOVING FROM CENTRAL/SRN MN TO THE CENTRAL U.P. MON AFTERNOON/EVENING. THE WARM FRONT ASSOCIATED WITH THE SYSTEM LOOKS TO HANG UP OVER CENTRAL OR NRN WI...WHICH IS SUFFICIENT TO KEEP LIKELY/CATEGORICAL POPS OVER THE CWA. THE FORECAST FOR MON IS EXTREMELY DEPENDENT ON CONVECTION AND EXACTLY WHERE THE WARM FRONT SETS UP. MORNING CONVECTION WILL PLAY A ROLE IN THE COMPLICATION...WITH AN UNKNOWN LEVEL OF CLEARING/DESTABILIZATION. CURRENT THINKING CONTINUES TO BE THAT EITHER A STRONG CONVECTIVE COMPLEX OR CLUSTER OF SUPERCELL STORMS WILL MOVE S OF THE CWA IN THE AFTERNOON/EVENING. HOWEVER...IF THE FRONT SURGES FARTHER N OR IF ENOUGH INSTABILITY CAN DEVELOP...SHEAR WILL BE VERY STRONG AND THE OVERALL SYSTEM QUITE POTENT SO SEVERE STORMS WOULD LIKELY RESULT...WITH LARGE HAIL...DAMAGING WINDS AND TORNADOES ALL CONDITIONALLY POSSIBLE. IT SEEMS THAT SOME LOCATIONS IN THE WI/MI REGION (LIKELY FROM CENTRAL WI TO LOWER MI) WILL SEE A SIGNIFICANT SEVERE EVENT. AT THIS TIME WILL CONTINUE TO FAVOR A MORE CLIMATOLOGICAL APPROACH (WHICH IS SUPPORTED BY THE GFS/ECMWF/GEM) WHICH KEEP STRONGER STORMS S OF THE CWA AND WILL NOT PUT ANY STRONG/SEVERE EMPHASIS INTO THE HWO. SHOULD SEE GRADUALLY CLEARING CONDITIONS BY TUE MORNING WITH HIGH PRESSURE DOMINATING THE CENTRAL U.S.. SHOULD SEE MARINE FOG NEAR ERN LAKE SUPERIOR MON NIGHT AS NW WINDS BEHIND THE SHORTWAVE SWEEP FOG ONSHORE. OTHERWISE...SUNNY SKIES WILL PREVAIL ON TUE. NEXT CHANCE OF SHOWERS AND POSSIBLE SOME THUNDER ARRIVES ON WED AFTERNOON AND CONTINUES OFF AND ON THROUGH THU AS A SHORTWAVE MOVES THROUGH THE AREA. LIMITED THUNDER POTENTIAL TO SLIGHT CHANCES GIVEN LIMITED INSTABILITY. AN UPPER TROUGH LOOKS TO BECOME DOMINANT OVER THE GREAT LAKES REGION...WHICH WILL MAKE FOR COOLER CONDITIONS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 127 AM EDT SUN JUN 21 2015 LOW LEVEL MOISTURE WILL REMAIN INTO SUNDAY AFTERNOON BEFORE DRIER AIR ARRIVES. UNTIL THEN...VLIFR CONDITIONS WILL BE EXPECTED AT ALL THE TAF SITES INTO SUN MORNING BEFORE A SLOW IMPROVEMENT TO VFR TAKES PLACE SUN AFTERNOON AND LASTS INTO SUN EVENING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 420 PM EDT SAT JUN 20 2015 TYPICAL SUMMERTIME CONDITIONS WITH GENERALLY LIGHT WINDS WILL DOMINATE ACROSS LAKE SUPERIOR THROUGH THE FCST PERIOD. WITH WEAK HIGH PRES BUILDING INTO THE AREA BEHIND THE DISTURBANCE MOVING OUT OF THE AREA TONIGHT...LIGHTER WINDS WILL FOLLOW FOR THE LAST HALF THE WEEKEND. THESE LIGHT WINDS...UNDER 20KT...WILL LIKELY CONTINUE THRU THE FIRST HALF OF NEXT WEEK AS A WEAK SUMMERTIME PRES GRADIENT SHOULD PREVAIL. THE RAIN TODAY WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE. EXPECT THE FOG TO LINGER INTO EARLY NEXT WEEK DUE TO A LACK OF STRONG ADVECTION OF DRIER AIR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
129 AM EDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 420 PM EDT SAT JUN 20 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS. THE SHORTWAVE TROUGH THAT BROUGHT THE LARGE AREA OF RAIN THROUGH UPPER MI WAS EXITING THE AREA LEAVING MAINLY JUST PATCHY LIGHT RAIN OF DRIZZLE OVER THE NORTH AND EAST. ANOTHER TRAILING SHRTWV OVER NE MN SUPPORTED SCT SHRA FROM THE MN ARROWHEAD INTO WRN LAKE SUPERIOR. OTHER UPSTREAM SHORTWAVES WERE LOCATED OVER NRN ND AND SE SASK. TONIGHT...EXPECT ISOLD/SCT -SHRA INTO THE CWA THIS EVENING ASSOCIATED WITH THE MN SHRTWV THAT SHOULD DIMINISH AND END AFTER 03Z. OTHERWISE...WITH ABUNDANT LOW LEVEL MOISTURE OVER THE REGION...PATCHY FOG WILL SHOULD DEVELOP. NNW UPSLOPE 10-15 KNOT 950- 900 MB FLOW INTO N CNTRL UPPER MI MAY ALSO SUPPORT SOME DRIZZLE OVERNIGHT INTO EARLY SUNDAY. SUN...THERE MAY BE SOME ISOLATED LIGHT SHOWERS ASSOCIATED WITH THE SASK/ND SHRTWVS EARLY OVER THE NORTH. OTHERWISE...EXPECT A WEAK SFC RIDGE TO BUILD INTO THE AREA WITH MAINLY LIGHT WINDS ALLOWING LAKE BREEZES TO DEVELOP. MODEL CONSENSUS SHOWS MLCAPE VALUES COULD CLIMB INTO THE 500-1000 J/KG RANGE OVER MAINLY THE SRN CWA FROM NEAR IMT- MNM. THIS MAY BE ENOUGH TO ALLOW SOME SHRA/TSRA TO DEVELOP...ESPECIALLY NEAR THE LAKE MI BREEZE BOUNDARY. WITH LIMITED INSTABILITY FARTHER NORTH AND SOME MID LEVEL CAPPING NEAR 700 MB...NO AFTERNOON PCPN IS EXPECTED OVER THE REST OF THE CWA. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 310 PM EDT SAT JUN 20 2015 UPPER GREAT LAKES REGION WILL STILL BE UNDER THE INFLUENCE OF A HIGH PRESSURE RIDGE AT THE START OF THE LONG TERM PERIOD...BUT ITS INFLUENCE WILL BE SHORT LIVED AS A POTENT SHORTWAVE AND ASSOCIATED LOW PRESSURE SYSTEM WILL SWEEP ACROSS THE AREA ON MONDAY. THE SHORTWAVE THAT WILL AFFECT THE AREA ON MONDAY IS ACTUALLY TWO SEPARATE WAVES AT THIS TIME...ONE OVER BRITISH COLUMBIA AND THE OTHER OVER THE PACIFIC TO THE WEST OF OREGON. THESE TWO WAVES WILL MERGE OVER THE NORTHERN ROCKIES TOMORROW AND THEN QUICKLY SHIFT EAST INTO THE AREA FOR MONDAY. A LOW AVERAGING 1000MB WILL SLIDE NORTHEAST...TRACKING FROM EASTERN WYOMING ON SUNDAY AFTERNOON...TO MINNESOTA ON MONDAY AFTERNOON AND THEN ACROSS THE UPPER GREAT LAKES ON MONDAY NIGHT. MUCH OF THE FORECAST DEPENDS BOTH ON THE TRACK OF THE SHORTWAVE AND THE DEVELOPMENT OF CONVECTION ALONG THE WARM FRONT AHEAD OF THE LOW. LATEST MODEL RUNS SHOW THE SHORTWAVE TRACKING ACROSS SOUTHERN UPPER MICHIGAN OR NORTHERN WISCONSIN...WITH THE WARM FRONT LIKELY LOCATED IN NORTHERN/CENTRAL WISCONSIN. THAT IS CLOSE ENOUGH TO CONTINUE TO SHOW LIKELY TO DEFINITE POPS SPREADING EAST INTO THE AREA ON MONDAY MORNING AND CONTINUING INTO EARLY MONDAY EVENING AS THE MAIN FORCING MOVES THROUGH THE UPPER GREAT LAKES. THE POSITION OF THE WARM FRONT WILL DETERMINE SEVERE WEATHER POTENTIAL...AS THAT WILL BE THE AREA WHERE THE NOSE OF THE 35-40KT 850MB JET AND INSTABILITY GRADIENT WILL BE LOCATED. WHILE SOME MODELS DO TRY TO SHIFT IT NORTH INTO OUR AREA...BELIEVE THAT CONVECTION AND POSSIBLE MCS THAT DEVELOPS UPSTREAM IN MINNESOTA ON SUNDAY NIGHT WILL SUPPRESS THE BOUNDARY FARTHER TO THE SOUTH. ASSUMING THAT OCCURS...THE BETTER INSTABILITY WILL BE WELL TO THE SOUTH OF THE AREA AND THE GRADIENT SOMEWHERE IN CENTRAL/NORTHERN WISCONSIN. THINK THE LATEST DAY 3 OUTLOOK FROM SPC HAS A GOOD HANDLE ON WHERE THE STRONGEST STORMS WILL BE AND GENERALLY TO THE SOUTH OF THE U.P.. WILL CONTINUE TO MENTION SLIGHT/CHANCE THUNDERSTORMS OVER THE SOUTHERN HALF TO TWO-THIRDS OF THE CWA WHICH IS CLOSE ENOUGH TO POTENTIAL EXPERIENCE SOME RUMBLES OF THUNDER. WITH THE DYNAMICS OF THE SYSTEM...IF THE INSTABILITY OR WARM FRONT SHIFTS FARTHER TO THE NORTH...SEVERE STORMS WOULD BE POSSIBLE. AS THE LOW DEPARTS ON MONDAY NIGHT...EXPECT A WEST TO EAST DIMINISHMENT OF POPS AND CLOUD COVER ACROSS THE AREA. HAVE TRENDED WINDS UP BASED OFF ALL OF THE LATEST RUNS...WITH 925MB WINDS AROUND 35KTS. THAT WIND WILL LIMIT THE POTENTIAL FOR FOG ON MONDAY NIGHT ACROSS THE U.P.. THINK THE MAIN AREAS THAT WILL SEE FOG WILL BE ALONG THE LAKE MICHIGAN SHORELINE ON MONDAY EVENING AND SHORELINES ALONG CENTRAL/EASTERN LAKE SUPERIOR AS THE WINDS TURN TO THE NORTHWEST AND PUSH THE FOG ONSHORE. WINDS WILL BE DECREASING ON TUESDAY. THE AREA WILL BE UNDER WEST-NORTHWEST FLOW ALOFT FOR TUESDAY AND WEDNESDAY...AS A HIGH PRESSURE RIDGE MOVES OVER THE AREA FOR TUESDAY AND THEN DEPARTS ON WEDNESDAY AS THE PARENT HIGH MOVES INTO THE OHIO RIVER VALLEY. WHILE THE RIDGE IS OVER THE AREA...EXPECT DRY CONDITIONS AND TEMPERATURES TO BE NEAR NORMAL. THE NEXT SHORTWAVE WILL MOVE THROUGH THE AREA SOMETIME BETWEEN LATE WEDNESDAY AFTERNOON AND THURSDAY...THROUGH THE WEST-NORTHWEST FLOW ALOFT. WITH THE SOURCE REGION...AND THE WARM FRONT SITUATED OVER THE CENTRAL PLAINS...EXPECT MOISTURE TO BE LIMITED AND WILL ONLY INCLUDE SLIGHT/CHANCE POPS FOR THE PASSAGE OF THE WAVE. INSTABILITY IS ALSO LIMITED AND WILL KEEP VALUES CAPPED AT SLIGHT CHANCES...BUT WILL NEED TO WATCH DIURNAL HEATING ON THURSDAY...WHICH COULD INCREASE POTENTIAL SOME. A WEAK HIGH WILL MOVE OVER THE AREA ON THURSDAY NIGHT AND THE FIRST PART OF FRIDAY BEFORE ANOTHER SHORTWAVE DROPS SOUTHEAST INTO THE AREA FOR LATER FRIDAY INTO SATURDAY. WHILE THERE IS THE POTENTIAL FOR RAIN DURING THIS PERIOD...THE MORE NOTABLE ITEM IS THE AMPLIFICATION OF AN UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT WEEKEND AND LIKELY CONTINUING INTO NEXT WEEK. BOTH THE ECMWF/GFS ENSEMBLES SUPPORT THAT IDEA...AND EVEN SHOW HINTS OF THAT TROUGH REMAINING IN PLACE TOWARDS THE FOURTH OF JULY. IF THAT SETUP OCCURS...THE U.P. WOULD EXPERIENCE A COOL AND DRY PERIOD OF WEATHER FOR THE END OF JUNE AND START OF JULY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 127 AM EDT SUN JUN 21 2015 LOW LEVEL MOISTURE WILL REMAIN INTO SUNDAY AFTERNOON BEFORE DRIER AIR ARRIVES. UNTIL THEN...VLIFR CONDITIONS WILL BE EXPECTED AT ALL THE TAF SITES INTO SUN MORNING BEFORE A SLOW IMPROVEMENT TO VFR TAKES PLACE SUN AFTERNOON AND LASTS INTO SUN EVENING. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 420 PM EDT SAT JUN 20 2015 TYPICAL SUMMERTIME CONDITIONS WITH GENERALLY LIGHT WINDS WILL DOMINATE ACROSS LAKE SUPERIOR THROUGH THE FCST PERIOD. WITH WEAK HIGH PRES BUILDING INTO THE AREA BEHIND THE DISTURBANCE MOVING OUT OF THE AREA TONIGHT...LIGHTER WINDS WILL FOLLOW FOR THE LAST HALF THE WEEKEND. THESE LIGHT WINDS...UNDER 20KT...WILL LIKELY CONTINUE THRU THE FIRST HALF OF NEXT WEEK AS A WEAK SUMMERTIME PRES GRADIENT SHOULD PREVAIL. THE RAIN TODAY WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE. EXPECT THE FOG TO LINGER INTO EARLY NEXT WEEK DUE TO A LACK OF STRONG ADVECTION OF DRIER AIR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS DULUTH MN
357 PM CDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 315 PM CDT SUN JUN 21 2015 CANT RULE OUT A STRAY SPRINKLE/LIGHT SHOWER THIS EVENING AS LATEST SPC RUC ANALYSIS SHOWS 500-1000 J/KG OF CAPE SITTING OVER THE FORECAST AREA. CURRENT RADAR IMAGERY IS PICKING UP ON A FEW ISOLATED SHOWERS TRYING TO GAIN MOMENTUM OVER NW WISCONSIN. HOWEVER...THESE SHOWERS WILL DISSIPATE NEAR SUNSET WITH THE LOSS OF DAYTIME HEATING. FOCUS TURNS TO THE ON GOING CONVECTION IN THE DAKOTAS...WHERE A SVR THUNDERSTORM WATCH IS IN EFFECT. LATEST GUIDANCE CONTINUES TO SUGGEST AN APPROACHING SHORT WAVE WITH DEEPENING H85/SFC LOW WILL ALLOW THE CONVECTION TO DEVELOP INTO A MESOSCALE CONVECTIVE COMPLEX...WHICH TRANSLATES ACROSS THE EASTERN DAKOTAS AND INTO MINNESOTA OVERNIGHT. ALTHOUGH THE EXACT TRACK IS STILL SOMEWHAT UNCERTAIN...LATEST HIGH RESOLUTION MODELS SHOW THE CONVECTION REACHING THE WESTERN BORDER OF THE DLH CWA AROUND MIDNIGHT...REACHING THE TWIN PORTS AROUND DAY BREAK MONDAY. THE SHORT WAVES WITH SFC TROUGH/H85 LOW WILL CONTINUE ITS PUSH EAST ACROSS THE FORECAST AREA THROUGH MONDAY AFTERNOON. THERE IS A POTENTIAL FOR FEW STORMS TO BECOME STRONG TO SEVERE MONDAY. THE MAIN THREAT FOR SEVERE WEATHER WILL BE ASSOCIATED WITH THE FRONTAL PASSAGE OVER NORTHERN WISCONSIN. ALTHOUGH THERE IS SUFFICIENT SHEAR AND MOISTURE TO SUPPORT ORGANIZED CONVECTION ACROSS THE ENTIRE FORECAST AREA...THE CAPE VALUES ARE MAXIMIZED OVER WISCONSIN DURING THE LATE MORNING/EARLY AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 315 PM CDT SUN JUN 21 2015 .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) SEASONABLE TO MILD WEEK AHEAD WITH A CHANCE FOR SOME MID/LATE WEEK SHOWERS AND STORMS. ON THE SYNOPTIC SCALE THERE WILL BE FAST FLOW ALOFT WITH A 100KT JET STREAK MOVING ACROSS THE NORTHERN TIER OF THE COUNTRY THROUGH THE FIRST HALF OF THE WEEK. THIS IS MAINLY DUE TO A MID/UPPER LEVEL RIDGE ACROSS THE SOUTHERN PLAINS INTO THE SOUTHEAST. EXPECTING QUIET WEATHER ON TUESDAY...A CHANCE FOR SHOWERS AND STORMS LATE TUES INTO THURSDAY...THEN A SLIGHT CHANCE FOR PRECIP THROUGH THE WEEKEND. TEMPS WILL BE GENERALLY SEASONABLE TO MILD. MONDAY NIGHT...SHOWERS/STORMS SHOULD BE EXITING THE REGION FOLLOWING A LOW PRESSURE THAT MOVES THROUGH EARLIER IN THE DAY. PRECIP WILL LIKELY END BY 06Z AS SUBSIDENCE DEVELOPS...WITH THE BEST CHANCE FOR PRECIP ALONG THE INTERNATIONAL BORDER TO THE ARROWHEAD REGION. TUESDAY...GENERALLY SUNNY AND DRY DUE TO AN AREA OF HIGH PRESSURE OVER THE MID MISSISSIPPI VALLEY DRIFTING EAST. A FEW SHOWERS/STORMS MAY FIRE ALONG THE INTERNATIONAL BORDER DUE TO A WEAK FRONT DRIFTING SOUTH OUT OF CANADA. LOOKS LIKE ENOUGH INSTABILITY FOR A SMALL HAIL/GUSTY WIND THREAT FROM THE STRONGEST STORMS...BUT SHEAR ALOFT APPEARS TO BE INSUFFICIENT FOR WIDESPREAD SEVERE THUNDERSTORMS. RELATIVE HUMIDITY VALUES COULD DROP TO 35-40 PERCENT IN THE AFTERNOON...THOUGH THIS WILL DEPEND ON AFTERNOON CLOUD COVER. HIGHS IN THE MID TO UPPER 70S WITH A LIGHT WEST WIND. TUESDAY NIGHT INTO THURSDAY NIGHT...AS HIGH PRESSURE DRIFTS EASTWARD THERE WILL BE A NUMBER OF WEAK DISTURBANCES IN THE MID-LEVEL FLOW HEADED TOWARDS THE UPPER MIDWEST. THE PATTERN WILL BE FAIRLY COMPLEX...BUT IN GENERAL EXPECT PRECIP CHANCES TO INCREASE FROM LATE TUESDAY...THROUGH THURSDAY. MODEL DIFFERENCES MAKE IT TOUGH TO DETERMINE WHICH DAY WOULD HAVE THE BEST CHANCE FOR PRECIP...BUT NO DAY LOOKS LIKE A COMPLETE WASHOUT. TEMPS REMAINING NEAR NORMAL WITH HIGHS IN THE MID TO UPPER 70S AND LOWS IN 50S. FRI...SAT...SUN...SEASONABLE TO MILD PATTERN CONTINUES. FLOW ALOFT BECOMES MORE NORTHWESTERLY AS A RIDGE DEVELOPS OVER THE WEST COAST AND TROUGH EVENTUALLY DEEPENING OVER THE EASTERN THIRD OF THE COUNTRY. THIS PATTERN WILL RESULT IN THE UPPER MIDWEST CONTINUING TO BE IN THE PATH OF A NUMBER OF WEAK DISTURBANCES AND FRONTAL PASSAGES. ECMWF/GFS/GEFS ARE ALL IN FAIRLY GOOD AGREEMENT WITH THIS PATTERN...AND ALSO DEEPEN AN UPPER LOW SOMEWHERE NEAR HUDSON BAY...WHICH MAY RESULT IN MORE ORGANIZED PATTERN SATURDAY/SUNDAY. TEMPS AGAIN MORE OF THE SAME...HIGHS IN THE MID TO UPPER 70S AND LOWS IN THE 50S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1216 PM CDT SUN JUN 21 2015 VFR CONDITIONS THIS AFTERNOON WITH A CHANCE FOR MVFR CEILINGS WITH THE POSSIBILITY FOR ISOLATED SHOWERS AND MAYBE A THUNDERSTORM THIS AFTERNOON...THEN TURNING MVFR TO IFR LATE TONIGHT INTO MONDAY MORNING DUE TO INCOMING SHOWERS AND THUNDERSTORMS. WINDS LIGHT THROUGH THE TAF PERIOD...WESTERLY AT 5 TO 10 KTS THIS AFTERNOON BECOMING SOUTHERLY OVERNIGHT. WILL BE WATCHING AN INCOMING THUNDERSTORM COMPLEX OVERNIGHT TONIGHT WHICH WILL LEAD TO SHOWERS AND STORMS THROUGH MONDAY MORNING...THOUGH CONFIDENCE IS BIT BELOW AVERAGE FOR WHAT STORM COVERAGE WILL BE LIKE THROUGH THE DAY. FOR NOW DECIDED TO STICK WITH VCTS MENTIONS AT MOST SITES. HIGHEST CONFIDENCE IN SHOWERS AND STORMS ROLLING THROUGH INL/HIB THIS MORNING...BUT THIS MAY CHANGE IN LATER FORECASTS AS THE UPSTREAM CONVECTION DEVELOPS AND EVOLVES. && .PRELIMINARY POINT TEMPS/POPS... DLH 55 72 53 76 / 50 70 10 0 INL 54 67 51 75 / 70 80 20 20 BRD 61 77 55 78 / 70 70 0 0 HYR 58 75 56 76 / 30 70 10 0 ASX 54 74 55 76 / 20 70 10 0 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. LS...NONE. && $$ SHORT TERM...GRANING LONG TERM...JJM AVIATION...JJM
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
352 PM CDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 352 PM CDT SUN JUN 21 2015 NICE AFTERNOON UNFOLDING WITH HIGH PRESSURE OVERHEAD. FORECAST FROM THE OVERNIGHT IS WORKING OUT NICELY...WITH MOST LOCATIONS WELL ON THEIR WAY TOWARD THE MID 80S. ONLY CHANGE MADE TO THE GRIDS THIS AFTERNOON WAS TO REMOVE THE ISOLATED THUNDERSTORM MENTION AS RAP SB/MLCAPE FORECAST SHOW NO INSTABILITY DEVELOPING IN THE MPX AREA THIS AFTERNOON. THIS GIVES US A NICE CLEAN SLATE FROM WHICH TO WORK WITH FOR THE MAIN SHOW WEATHER-WISE FOR LIKELY THE NEXT WEEK. WATER VAPOR IMAGERY THIS AFTERNOON SHOWS TWO WAVES OF INTEREST. ONE IS OVER SRN ALBERTA WITH THE OTHER MOVING ACROSS OREGON. THE NRN STREAM WAVE IS ALREADY SPARKING OFF THUNDERSTORM IN THE ND/MT/SASK BORDER REGION. EXPECT THESE STORMS TO CONGEAL INTO A LINEAR SYSTEM LATER THIS AFTERNOON THAT WILL BE APPROACHING THE NW MPX CWA BY 6Z. AS WE GET TOWARD 6Z...THE WAVE CURRENTLY OVER OREGON WILL BE OUT OVER THE BLACK HILLS...WITH HI-RES AND DETERMINISTIC MODELS SHOWING THIS WAVE LEADING TO ANOTHER AREA OF THUNDERSTORMS DEVELOPING OVER NORTHERN SODAK. BASED ON REFLECTIVITY FORECASTS AND STORM TOTAL PRECIPITATION SWATHS...LOOKS LIKE THESE TWO WAVES WILL MAINTAIN THEIR SEPARATION. THIS WILL RESULT IN ONE COMPLEX OF STORMS MOVING ACROSS CENTRAL/NRN MN TONIGHT...WITH ANOTHER COMING OUT OF SODAK AND ACROSS SRN MN LATE TONIGHT/MONDAY MORNING AND GOING INTO SE WI BY MONDAY AFTERNOON. THE TWO SCENARIOS WE ARE SEEING IN THE GUIDANCE IS 1) THE NRN WAVE REMAINS DOMINATE...DRIVING ONE COMPLEX ACROSS CENTRAL/NRN MN...WITH NOT MUCH SOUTH. 2) THE NRN COMPLEX DIES OUT AS IT MOVES ACROSS CENTRAL MN...WITH THE SRN COMPLEX ENTERING WRN MN AROUND 9Z AND MOVING OUT OF THE EAST END OF THE MPX CWA BY 18Z. THE GEM IS ABOUT THE ONLY MODEL PLAYING INTO SCENARIO 1...SO CURRENT GRIDS ARE GOING DOWN THE SCENARIO 2 ROUTE...WHICH IN ONE FLAVOR OR ANOTHER IS SUPPORTED BY THE HRRR/ARW/NMM/ECMWF/NAM/GFS. FROM THE SEVERE THREAT...THE NRN COMPLEX OF STORMS MAY BE ABLE TO PRODUCE A WIND GUST OR TWO...BUT THE SEVERE RISK FOR TONIGHT THROUGH MONDAY MORNING REALLY HINGES ON HOW THE SRN WAVE EVOLVES. THE SEVERE PARAMETERS FOR SCENARIO 2 CONTINUE TO BE IMPRESSIVE WITH A 110 KT UPPER JET AND 80 KT WRLY MID LEVEL JET STREAK AS MUCAPE UPWARDS OF 4000 J/KG COMES UP OUT OF IOWA. BOTH THERMODYNAMIC AND KINEMATIC PARAMETERS CONTINUE SUPPORT THE DEVELOPMENT OF A BOWING MCS. FOR THE SEVERE THREAT...THE QUESTION BECOMES CAN WE OVERCOME A STABLE NOCTURNAL BOUNDARY LAYER. FORECAST SOUNDINGS SHOW THAT THE MUCAPE VALUES NOTED ABOVE RESULT FROM LIFTING A PARCEL OFF A WARM NOSE CENTERED AROUND THE H9 LEVEL. IF THIS STABLE LAYER HOLDS...THEN WE WOULD LIKELY SEE JUST AN ISOLATED SEVERE WIND THREAT THROUGH THE NIGHT. IF THIS COMPLEX CAN OVERCOME THIS STABLE NEAR SURFACE LAYER...THE POTENTIAL IS THERE FOR A WIDESPREAD SIGNIFICANT WIND EVENT. IN FACT...THERE IS POTENTIAL WE COULD SEE A SIGNIFICANT DERECHO OUT OF THIS EVENT...WITH WIDESPREAD WIND DAMAGE FROM ABERDEEN SOUTH DAKOTA ALL THE WAY TOWARD DETROIT THROUGH THE COURSE OF MONDAY. THERE IS A GOOD CHANCE THAT THE LATER COULD COME TRUE BASED ON STORM MOTION. CORFIDI VECTORS AND FORWARD MOTION OF THE BOWING SEGMENT IN THE HI-RES ARW REFLECTIVITY FORECAST SUPPORT A STORM MOTION OF 60-65 MPH...SO JUST THAT ON ITS OWN COULD LEAD TO A LOT OF ISSUES. ON THE BRIGHT SIDE THOUGH...THIS TYPE OF STORM MOTION WILL KEEP THE FLASH FLOOD THREAT LOW...AS PWATS WILL BE BE PUSHING 2 INCHES AS THE SRN STREAM WAVE MOVES THROUGH. FOR THE REST OF MONDAY...THE MORNING ACTIVITY LOOKS TO PRETTY MUCH CLEAN US OUT...WITH A COLD FRONT CLEARING THE ERN MPX CWA A LITTLE AFTER 18Z. BY THE AFTERNOON...IT WILL BE BEAUTIFUL...WITH TEMPERATURES AROUND 80 AND BREEZY NW WINDS THAT WILL LIKELY BE GUSTING 25-30 MPH OUT IN WRN MN AS WE DRY OUT. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 352 PM CDT SUN JUN 21 2015 THE FIRST FULL WEEK OF SUMMER DOESN/T LOOK TOO BAD WEATHERWISE AS THE UPPER AIR PATTERN TRANSITIONS FROM STRONG WESTERLY FLOW TO A RIDGE IN THE WEST/TROUGH IN THE EAST. THIS HAS BEEN WELL ADVERTISED FOR MANY DAYS NOW ON THE GFS/ECMWF. THIS WILL KEEP THE MAIN FRONTAL BOUNDARY WELL TO OUR SOUTH...ESSENTIALLY RUNNING FROM THE CENTRAL PLAINS TO THE MID ATLANTIC STATES. FORECASTWISE...IT LOOKS DRY FROM MONDAY NIGHT INTO WEDNESDAY AS HIGH PRESSURE SLIDES SLOWLY EASTWARD ACROSS THE UPPER MISSISSIPPI VALLEY. THEREAFTER...WEAK PURTABATIONS IN THE DEVELOPING NORTHWEST FLOW ACROSS THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY REGION WILL BRING SMALL CHANCES FOR SHOWERS AND ISOLATED THUNDERSTORMS. THE PERIODS WITH THE BEST AGREEMENT ARE LATE WEDNESDAY/WEDNESDAY NIGHT AND THEN FRIDAY INTO SATURDAY. RAIN AMOUNTS WITH BOTH OF THESE EVENTS LOOK LIGHT. EVEN WITH THE NORTHWEST FLOW PATTERN...HIGH TEMPERATURES WILL REMAIN CLOSE TO SEASONAL NORMALS WITH UPPER 70S TO LOWER 80S COMMON. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 111 PM CDT SUN JUN 21 2015 MAIN CONCERN THIS TAF PERIOD IS THE POTENTIAL FOR SIGNIFICANT TSRA ACTIVITY TONIGHT INTO MONDAY MORNING. FAVORED THE IDEA OF THE GFS/HRRR FOR THESE TAFS. WITH THAT...EXPECT THUNDERSTORMS TO DEVELOP THIS AFTERNOON IN WRN NODAK THAT WILL SEND A COMPLEX OF TSRA INTO CENTRAL MN AFTER 6Z. HENCE BRINGING SHRA MENTION IN MUCH EARLIER FOR AXN/STC. AS THIS IS GOING ON...WE SHOULD SEE CONVECTION RAPIDLY EXPAND ACROSS NORTH CENTRAL SODAK THAT WILL BECOME THE PRIMARY TSRA COMPLEX...ENTERING WRN MN AROUND 9Z. FORWARD MOTION ON THIS SYSTEM WILL LIKELY BE PUSHING 60 KTS...SO IT SHOULD WAIST NO TIME IN WORKING ACROSS THE AREA...REACHING THE TWIN CITIES AROUND 12Z AND PUSHING INTO EAU BY 15Z. IS POTENTIAL FOR SIGNIFICANT WIND GUSTS WITH THIS SRN SYSTEM. PUT SOME MVFR CIGS IN FOR BEHIND THIS ANTICIPATED COMPLEX...BUT HAVE LESS CONFIDENCE ON HOW EXTENSIVE ANY OF THAT WILL BE. KMSP...CONFIDENCE CONTINUES TO INCREASE ON A SIGNIFICANT LINE OF STORMS IMPACTING MSP DURING THE PEAK OF THE MORNING RUSH...SO IMPACT TO TRAFFIC COULD BE SIGNIFICANT IN THE MORNING. WILL HAVE TO WATCH HOW FAR SOUTH THE NODAK COMPLEX BUILDS...HRRR IS INDICATING THE SOUTH END BEING WELL SOUTH OF I-94. IF THE HRRR IS RIGHT...WE COULD SEE ONE ROUND OF STORMS AROUND 9Z...WITH THE SODAK BATCH GETTING HERE CLOSER TO 12Z. /OUTLOOK FOR KMSP/ TUE...VFR. WINDS NW TO W AT 5-10 KT. WED...VFR. CHC OF TSRA. WINDS SE 5 KTS. THU...VFR. WINDS N 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...RAH AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
111 PM CDT SUN JUN 21 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 455 AM CDT SUN JUN 21 2015 SEMI-ZONAL FLOW REMAINS IN TACT THROUGH THE SHORT TERM PERIOD...WITH THE NEXT ROUND OF EMBEDDED SHORTWAVE ENERGY TO ARRIVE LATER TODAY. IN THE MEANTIME...TODAY WILL BE A BIT WARMER THAN NORMAL. EXPECT TEMPERATURES TO MODERATE INTO THE LOW TO MID 80S UNDER WESTERLY LOW LEVEL FLOW...PER FORECAST MODEL SOUNDINGS WHICH ILLUSTRATE MIXING TO AROUND 800MB. BY MID AFTERNOON...HI RES MODELS INDICATE POCKETS OF 1500-2000 J/KG ML CAPES DEVELOPING FROM WEST INTO SOUTH CENTRAL MINNESOTA...AS A WARM FRONT LIFTS NORTH TOWARD THE AREA. HAVE THEREFORE INCLUDED A MENTION OF ISOLATED THUNDERSTORMS...ALTHOUGH MOST LOCATIONS SHOULD EXPERIENCE A DRY SUNDAY. THE AFOREMENTIONED FRONT AND ATTENDANT SFC LOW WILL BECOME THE FOCI FOR WIDESPREAD THUNDERSTORM DEVELOPMENT TONIGHT...AS STOUT MOISTURE ADVECTION DEVELOPS ON THE NOSE OF A 50KT LOW LEVEL JET. THE RESULTANT DEVELOPMENT OF A MCS APPEARS LIKELY...WITH CATEGORICAL POPS SPREADING INTO THE AREA BETWEEN 06Z AND 12Z MONDAY. HIGHLY IMPRESSIVE DIFFERENTIAL DIVERGENCE IS PROGGED TO BLOSSOM OVER SOUTH CENTRAL MN DURING THIS TIME AS WELL...BY BOTH GFS AND NAM SOLUTIONS...GIVEN THE COUPLED JET STRUCTURE. THIS WILL POSE A RISK FOR SEVERE WINDS TO ACCOMPANY THE THUNDERSTORM COMPLEX. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 455 AM CDT SUN JUN 21 2015 FROM A BIG PICTURE PERSPECTIVE...RELATIVELY STRAIGHT FORWARD FORECAST FOR THE EXTENDED PERIOD. ZONAL FLOW WILL CONTINUE THROUGH THE MIDDLE OF THE WEEK...WITH A TRANSITION TO NORTHWEST FLOW OVER THE UPCOMING WEEKEND. THE FRONTAL BOUNDARY THAT MOVED THROUGH THE REGION FRIDAY NIGHT...AND WAS THE FOCUS FOR CONVECTION ON SATURDAY...WILL LAY OUT EAST-TO-WEST AND OSCILLATE NORTH AND SOUTH BETWEEN THE I-70 AND I-90 CORRIDORS FOR THE NEXT SEVERAL DAYS. THIS WILL CONTINUE TO BE THE FOCUS FOR THUNDERSTORMS WITH SEVERE WEATHER POTENTIAL. AS ALLUDED TO IN THE SHORT TERM DISCUSSION...LATE SUNDAY NIGHT INTO MONDAY WILL BE THE PERIOD OF INTEREST TO WATCH...AS FORECAST ANALOGS AND MODEL GUIDANCE POINT TO A POTENTIALLY SIGNIFICANT STRAIGHT LINE WIND EVENT ALONG THE EAST/WEST ORIENTED AFOREMENTIONED BOUNDARY. THE NUMBER 1 CIPS ANALOG ACCORDING TO THE 21.00 NAM IS MAY31 1998...WHICH WAS A HIGH END DERECHO ACROSS THE GREAT LAKES REGION. GIVEN THAT INFORMATION...A THOROUGH INVESTIGATION OF THE MONDAY 12-24Z TIME PERIOD IS WARRANTED. AT THE START OF THE PERIOD...12Z MONDAY...AN MCS SHOULD ALREADY BE ONGOING ACROSS THE FORECAST AREA. A FEW THINGS STAND OUT IN THE FORECAST MODELS. FIRST IS THE FAVORABLE SHEAR PROFILE. THE DIRECTIONAL AND SPEED COMPONENT YIELD 60 TO 80KTS OF DEEP LAYER SHEAR. MEANWHILE...THE 0-3KM SHEAR IS ON THE ORDER OF 35 TO 45KTS AND IS ORIENTED EAST/WEST...WHICH WOULD BE NORMAL TO A BOW ECHO AND PROMOTES THE UPDRAFT PLACEMENT ABOVE THE COLD POOL WHICH IS FAVORABLE FOR A LONG LIFE CYCLE OF THE BOW. LOOKING BACK AT THE DATA FROM THIS PAST SATURDAY MORNING...THE EVENTS ARE FAIRLY SIMILAR FROM A SHEAR PERSPECTIVE...BUT ONE OF THE TWO GLARING DIFFERENCES IS THE LACK OF INSTABILITY THAT WAS IN PLACE ACROSS MN AND FARTHER EAST...WHICH GIVEN THE BENEFIT OF HINDSIGHT LED TO A QUICK REDUCTION IN THE SEVERE THREAT BY 12Z SATURDAY. HOWEVER...MODEL GUIDANCE SHOWS ANYWHERE FROM 2000 TO 3500 J/KG OF CAPE POOLED ALONG I-90 AT 12Z MONDAY...WHICH SHOULD ALLOW THE CONVECTION TO MAINTAIN ITSELF THROUGH THE EARLY MORNING HOURS...AND PERHAPS STRENGTHEN DOWNSTREAM TOWARD MID MORNING WITH THE DESTABILIZATION OF DIABATIC HEATING. THE SECOND DIFFERENCE IS THE STRENGTH OF THE UPPER LEVEL JET...WHICH WAS ON THE ORDER OF 65 TO 75 KTS ON SATURDAY...BUT SHOULD RANGE FROM 90 TO 100 KTS WITH THIS COMING SYSTEM. THIS COMPARES MORE CLOSELY TO THE 100-115 KT JET OBSERVED IN THE 00Z KMPX RAOB FROM MAY 31 1998. THIS IS MERELY ANECDOTAL EVIDENCE THAT THE ATMOSPHERIC INGREDIENTS ARE IN PLACE FOR A SIGNIFICANT WIND EVENT...AND NOT A PREDICTION OF A REPEAT OF THE 1998 EVENT OR AN ATTEMPT TO INTRODUCE FEAR. INSTEAD...THIS EVENT SEEMS SIMILAR TO THE JUNE 30 EVENT OF LAST YEAR ACROSS IOWA AND ILLINOIS...ONLY DISPLACED FARTHER NORTH. THE UNIQUE ASPECT OF THAT EVENT WAS THE MULTIPLE ROUNDS OF CONVECTION. SOME OF THE HIRES MODELS TRY TO HINT AT THIS SCENARIO. HOWEVER...WITH THE JUN 30 2014 EVENT THERE WAS A MUCH STRONGER UPPER LEVEL LOW THAT CONTINUALLY FORCED CONVECTION...AND THAT DOESNT SEEM TO BE THE CASE IN THIS EVENT. INSTEAD ANTICIPATE ONE QUICK MOVING LINE OF PRECIP...AND THEREFORE WENT VERY AGGRESSIVE WITH THE REMOVAL OF POPS MONDAY AFTERNOON. PWAT VALUES ARE HIGH...BUT GIVEN THE SPEED OF CONVECTION NOT ANTICIPATING ANY HYDRO PROBLEMS UNLESS MULTIPLE ROUNDS OF STORMS DOES INDEED DEVELOP. IN SUMMARY...MONDAYS SHEAR/CAPE/FORCING INGREDIENTS ARE THE MOST FAVORABLE OF THE YEAR FOR SEVERE WEATHER...AND WOULD NOT BE SURPRISED TO SEE SPC UPGRADE THE RISK TO MODERATE ONCE CONFIDENCE IN LOCATION INCREASES. THE PRIMARY THREAT IS DAMAGING WIND WITH AN ORGANIZED LINE OF STORMS. THE 21.00 WRFARW AND EMC-WRFNMM FIT THE CONCEPTUAL MODEL THE BEST IN PLACEMENT...AND FEEL THE QUICKER TIMING OF THE ECM-WRFNMM MAY BE MORE ACCURATE THAN THE SLIGHTLY SLOWER WRFARW. USED MODEL CONSENSUS FOR THE REST OF THE EXTENDED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 111 PM CDT SUN JUN 21 2015 MAIN CONCERN THIS TAF PERIOD IS THE POTENTIAL FOR SIGNIFICANT TSRA ACTIVITY TONIGHT INTO MONDAY MORNING. FAVORED THE IDEA OF THE GFS/HRRR FOR THESE TAFS. WITH THAT...EXPECT THUNDERSTORMS TO DEVELOP THIS AFTERNOON IN WRN NODAK THAT WILL SEND A COMPLEX OF TSRA INTO CENTRAL MN AFTER 6Z. HENCE BRINGING SHRA MENTION IN MUCH EARLIER FOR AXN/STC. AS THIS IS GOING ON...WE SHOULD SEE CONVECTION RAPIDLY EXPAND ACROSS NORTH CENTRAL SODAK THAT WILL BECOME THE PRIMARY TSRA COMPLEX...ENTERING WRN MN AROUND 9Z. FORWARD MOTION ON THIS SYSTEM WILL LIKELY BE PUSHING 60 KTS...SO IT SHOULD WAIST NO TIME IN WORKING ACROSS THE AREA...REACHING THE TWIN CITIES AROUND 12Z AND PUSHING INTO EAU BY 15Z. IS POTENTIAL FOR SIGNIFICANT WIND GUSTS WITH THIS SRN SYSTEM. PUT SOME MVFR CIGS IN FOR BEHIND THIS ANTICIPATED COMPLEX...BUT HAVE LESS CONFIDENCE ON HOW EXTENSIVE ANY OF THAT WILL BE. KMSP...CONFIDENCE CONTINUES TO INCREASE ON A SIGNIFICANT LINE OF STORMS IMPACTING MSP DURING THE PEAK OF THE MORNING RUSH...SO IMPACT TO TRAFFIC COULD BE SIGNIFICANT IN THE MORNING. WILL HAVE TO WATCH HOW FAR SOUTH THE NODAK COMPLEX BUILDS...HRRR IS INDICATING THE SOUTH END BEING WELL SOUTH OF I-94. IF THE HRRR IS RIGHT...WE COULD SEE ONE ROUND OF STORMS AROUND 9Z...WITH THE SODAK BATCH GETTING HERE CLOSER TO 12Z. /OUTLOOK FOR KMSP/ TUE...VFR. WINDS NW TO W AT 5-10 KT. WED...VFR. CHC OF TSRA. WINDS SE 5 KTS. THU...VFR. WINDS N 5-10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...LS LONG TERM...JRB AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1154 PM CDT SAT JUN 20 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 359 PM CDT SAT JUN 20 2015 WE REMAIN WITHIN A BELT OF RATHER HEALTHY WESTERLIES TODAY...THOUGH WATER VAPOR IMAGERY SHOWS WE ARE IN A ZONE OF SUBSIDENCE AND DRYING IN THE WAKE OF THE WAVE THAT PUSHED THE SHOWERS AND THUNDERSTORMS ACROSS THE REGION THIS MORNING. AT THE SFC...A TROUGH WITH A WIND SHIFT OVER TO THE NW HAD PUSHED TO ABOUT I-35 AS OF 230 PM. SPC MESO- ANALYSIS SHOWS 500-1500 J/KG OF MLCAPE ACROSS MOST OF THE AREA. HOWEVER...VIEW OUT THE WINDOW AND ON VISIBLE SATELLITE SHOWS THE CU FIELD ASSOCIATED WITH THIS INSTABILITY HAS A RATHER STABLE LOOK TO IT...SO NOT ANTICIPATING MUCH IN THE WAY OF PRECIP THIS AFTERNOON. SOME OF THE HI-RES CAMS /ESPECIALLY THE HRRR/ CONTINUE TO DEVELOP SOME ISO/SCT SHOWERS ALONG/AHEAD OF THE TROUGH FROM EC MN INTO WC MN...SO HAVE CONTINUED MENTION OF 20/30 POPS THIS AFTERNOON IN OUR EAST TO ACCOUNT FOR THAT. NEXT AREA TO WATCH FOR PRECIP THIS EVENING IS WRN MN. IR IMAGERY SHOWS A SHORT WAVE WORKING ACROSS NW SODAK. STARTING TO SEE STORMS BUBBLE UP FROM NW SODAK INTO NC NODAK BENEATH A PLUME OF STEEP MID- LEVEL LAPSE RATES. THE HRRR HAS PICKED UP ON THIS BIT OF FORCING...SHOWING A BROKEN LINE OF THUNDERSTORMS MOVING ACROSS THE DAKOTAS THE REST OF THE AFTERNOON AND MAKING A RUN FOR WEST CENTRAL MN BETWEEN 7PM AND 10PM. AS THESE STORMS RUN TOWARD MN...THE RAP SHOWS MUCAPE WANING...SO THINK THESE WILL RUN OUT OF STEAM BEFORE GETTING INTO MN...THOUGH WE MAY NEED TO GET SOME LOW PROBS FOR -SHRA INTO OUR WEST THIS EVENING. NEXT FEATURE OF INTEREST IS A STRONG SHORTWAVE EVIDENT ON WATER VAPOR IMAGERY THAT BETWEEN 7 AM AND 3 PM HAS GONE FROM OFF THE OREGON COAST TO WRN MT. DETERMINISTIC MODELS AND CAMS ARE IN GOOD AGREEMENT ON THIS WAVE KICKING OFF ANOTHER MCS OVER THE BLACK HILLS TONIGHT THAT WILL DIVE SE TOWARD OMAHA. AS IT DOES SO...ITS OUTFLOW BOUNDARY WILL BECOME A WARM FRONT THAT WILL BEGIN LIFTING NORTH ACROSS NEBRASKA TOWARD SW MN SUNDAY AFTERNOON. NAM/GFS SHOW A BAND OF ENHANCED INSTABILITY /1000-1500 J/KG OF MLCAPE/ DEVELOPING DURING THE AFTERNOON MORE OR LESS ALONG THE UPPER MN RIVER VALLEY. SEEING SOME INDICATIONS IN BOTH CAMS AND DETERMINISTIC MODELS OF SOME ISO/SCT TYPE CONVECTION DEVELOPING SUNDAY AFTERNOON WITHIN THIS INSTABILITY AXIS...SO HAVE LEFT SOME 20 POPS IN THERE TO ACCOUNT FOR THAT...THOUGH EXPECT IT TO BE MAINLY DRY FOR SUNDAY. FOR THE FOG THREAT TONIGHT...THINK NAM IS OVERDONE WITH THE AMOUNT OF LOW LEVEL MOISTURE IT HAS AND IS THEREFORE OVERDOING ITS FOG POTENTIAL IN WRN WI. LIKE THE IDEA OF THE RAP/GFS WITH FOG THREAT BEING PRIMARILY UP NE MN INTO NW WI. FINALLY...DID BOOST HIGHS FOR SUNDAY A FEW DEGREES ACROSS THE AREA. NAM/GFS SHOW US MIXING UP TO 800 MB...AND MIXING DOWN FROM THIS LEVEL YIELDED POTENTIAL HIGHS IN THE MID/UPPER 80S...SO MIXED THAT IN WITH OUR GOING FORECAST TO GET MOST FOLKS UP INTO THE LOW/MID 80S FOR HIGHS SUNDAY. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 359 PM CDT SAT JUN 20 2015 CONCERNS IN THE LONG TERM ARE CENTERED AROUND SEVERE WEATHER CHANCES SUNDAY NIGHT AND MONDAY AS A DEEPENING SHORT WAVE PASSES ACROSS THE FA. THIS RESULTS IN STRENGTHENING SURFACE LOW PRESSURE OVER SOUTH DAKOTA SUNDAY NIGHT ALONG WITH A WARM FRONT LIFTING NORTHEAST INTO SOUTHERN MINNESOTA AND WISCONSIN LATE IN THE NIGHT. MODEL CONSENSUS INDICATES THE NOSE OF THE LOW LEVEL JET EXCEEDS 50 KNOTS INTO SOUTH CENTRAL AND SOUTHEAST MINNESOTA MONDAY MORNING ACCOMPANIED BY PW VALUES IN EXCESS OF 2 INCHES...ONCE AGAIN ABOVE THE TOP OF KMPX SOUNDING CLIMATOLOGY. THE LOW AND WARM FRONT SHOULD PUSH RATHER QUICKLY ACROSS THE FA DURING THE DAY ON MONDAY WITH SEVERE WEATHER CHANCES LESSENING IN THE AFTERNOON. THE SETUP SUNDAY NIGHT AND EARLY MONDAY SHOULD YIELD A COMPLEX OF STORMS PUSHING ACROSS SOUTHERN MN AND ADJOINING AREAS OF WI. PROFILE DATA INDICATES A STRONG WARM LAYER DEVELOPING IN THE LOW LEVELS DURING THE NIGHT WITH VIRTUALLY ALL OF THE CAPE (1500 J/KG) BEING ABOVE 850 MB. HENCE...DUE TO THE STRONGLY VEERING WIND PROFILE CONFIDENCE FOR HAIL IS HIGHER THAN WIND EARLY ON IN THIS EVENT. IN ADDITION...THE 925-850MB FN VECTOR DIVERGENCE ALSO RUNS ALONG THE I-90 CORRIDOR LEADING TO HIGHER CONFIDENCE ON WHERE THE HEAVIEST RAIN MAY FALL. AT THIS POINT...CAMS THAT REACH OUT TO MONDAY MORNING ARE SHOWING A COMPLEX OF STORMS PASSING ALONG THE MN/IA BORDER. THEREFORE...COLLABORATION TODAY WAS TO BREAK POPS INTO 3 HOUR GROUPS AND DRIVE THUNDERSTORMS ACROSS OUR FAR SOUTHERN FA LATE SUNDAY NIGHT AND EARLY MONDAY. IN THE WAKE OF THIS FEATURE...MONDAY NIGHT AND TUESDAY ARE DRY AS HIGH PRESSURE SLIDES BY. A SURFACE FRONTAL BOUNDARY WILL BE STRENGTHENING ACROSS THE CENTRAL PLAINS INTO THE LOWER GREAT LAKES FOR WEDNESDAY AND THURSDAY WITH THE HIGHEST CHANCES FOR PRECIPITATION TO OUR SOUTH WITH SMALL CHANCES EXTENDING ACROSS PORTIONS OF OUR FA. CONFIDENCE IS NOT HIGH ON THE PRECIPITATION CHANCES FOR THESE PERIODS. THE STRONG WESTERLY UPPER AIR PATTERN IS STILL FORECAST TO BUCKLE LATE IN THE WEEK AND WEEKEND AS RIDGING DEVELOPS ACROSS IN THE WESTERN CONUS WITH A PRETTY DEEP TROUGH IN THE EAST. THIS TRANSITION PERIOD (FRIDAY AND SATURDAY) WILL OFFER THE NEXT PERIOD OF HIGH CHANCE POPS ACROSS THE FA. TEMPERATURES WILL BE CLOSE TO SEASONAL VALUES THROUGH THURSDAY WITH A SMALL DOWNWARD TREND ON HIGH TEMPERATURES THROUGH THE UPCOMING WEEKEND. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1150 PM CDT SAT JUN 20 2015 MAIN AVIATION CONCERN IS FOG POTENTIAL AT KRNH/KEAU OVERNIGHT AS LIGHT WINDS AND MOSTLY CLEAR SKIES SHOULD LEAD TO FOG FORMATION. HOW DENSE THE FOG BECOMES IS THE MAIN ISSUE. WILL CONTINUE WITH IFR CONDS AT BOTH KEAU/KRNH THRU 13Z /STARTING ARND 8Z/. OTHERWISE...VFR CONDS WILL PREVAIL ACROSS THE REST OF MPX CWA WITH WINDS GENERALLY FROM THE WNW TONIGHT/SUNDAY...BECOMING SW SUNDAY EVENING. ANY PRECIPITATION SHOULD HOLD OFF UNTIL AFT 6Z MONDAY. KMSP... HIGH CONFIDENCE IN VFR CONDS THRU MOST OF THE TAF PERIOD...WITH CONDS POSSIBLY LOWERING TO MVFR BY THE END OF THE TAF PERIOD WITH TSRA/SHRA. DUE TO UNCERTAINTIES ON TIMING OF THE NEXT SYSTEM MOVING ACROSS THE NORTHERN PLAINS/UPPER MIDWEST...WILL KEEP VFR AT THIS TIME WITH CIGS LOWERING TO 9K. WINDS WILL REMAIN FROM THE WNW TONIGHT/SUNDAY...BECOMING SW/S SUNDAY EVENING. /OUTLOOK FOR KMSP/ MON...VFR. CHC MVFR WITH AM TSRA/SHRA. WIND S 5-10 KT BCMG NW 10KTS. TUE...VFR. WINDS NW TO W AT 5 KT. WED...VFR. CHC OF TSRA. WINDS E-SE 5 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...MPG LONG TERM...RAH AVIATION...JLT
AREA FORECAST DISCUSSION
NWS JACKSON MS
1045 AM CDT SUN JUN 21 2015 .UPDATE...SURFACE ANALYSIS HAD A 1021MB RIDGE FROM THE NORTHERN GULF NOSING UP ACROSS THE SOUTHWEST PORTIONS OF OUR CWA. RIDGING ALOFT WAS NOTED OVER THE SOUTHEAST STATES AND THE DESERT SOUTHWEST. RIDGING SURFACE AND ALOFT OVER OUR REGION WILL LIMIT RAIN CHANCES AND CONTRIBUTE TO WARMER TEMPERATURES THAT WILL COMBINE WITH HIGH HUMIDITY THE NEXT SEVERAL DAYS RESULTING IN HIGHER HEAT INDEX VALUES. TODAY...HEAT INDEX VALUES ARE EXPECTED TO EXCEED 100F IN MOST AREAS. CLOUD COVER DUE TO EARLY CONVECTION OVER NORTHEAST TEXAS HAS SPREAD OVER OUR WESTERN ZONES AND WAS LIMITING INSOLATION THERE SO FAR TODAY. HAVE LOWERED AFTERNOON HIGHS THERE A COUPLE OF DEGREES AND LOWER HEAT INDEX VALUES ARE NOW EXPECTED IN THE WEST TODAY. MUCH OF OUR CWA WILL NOT SEE ANY STORMS TODAY. ISOLATED TO SCATTERED SHOWERS AND STORMS WILL BE POSSIBLE IN THE SOUTH AND WEST. LOCAL WET MICROBURST CHECKLIST SUGGESTS POTENTIAL FOR ANY STORMS THAT DEVELOP. DUE TO GREATER INSTABILITY...OUR SOUTHERN ZONES WILL SEE THE BEST CHANCE TODAY FOR A STRONG STORM OR TWO CAPABLE OF 40 TO 50 MPH WIND GUSTS. /22/ && .AVIATION...OTHER THAN SOME VCTS AROUND JAN/HKS/MEI AND HBG THIS AFTERNOON...VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD./26/ && .PREV DISCUSSION... /ISSUED 451 AM CDT SUN JUN 21 2015/ DISCUSSION...TODAY THROUGH MONDAY NIGHT...THE SUBTROPICAL RIDGE WILL GRADUALLY BUILD OVER THE ARKLAMISS AS WE GO THROUGH EARLY THIS WEEK...EVENTUALLY PEAKING OVER THE AREA LATER IN THE WEEK. IN THE NEAR TERM...A WEAKNESS IN THE RIDGE JUST WEST OF THE ARKLAMISS WILL HELP TO DRAW DEEP LAYER MOISTURE NORTHWARD. THIS HIGH PRECIPITABLE WATER AIR WILL CIRCULATE THROUGH THE RIDGE AND HELP TO INCREASE DIURNAL CONVECTIVE POTENTIAL IN SPITE OF MOSTLY SUBSIDENT ANTI- CYCLONIC FLOW. THE MAIN FOCUS FOR CONVECTIVE POTENTIAL LATE THIS AFTN/EVNG SHOULD BE OVER THE PINE BELT WHERE COASTAL CONVERGENCE AND LESS RIDGE INFLUENCE WILL BE FELT...A ALONG/W OF THE MS RIVER IN CLOSER PROXIMITY TO RIDGE WEAKNESS. THE SPC SSEO REFLECTS THIS GENERAL PATTERN AS DOES THE HRRR...ALTHOUGH THE HRRR SEEMS A BIT TOO GENEROUS WITH COVERAGE. IN ANY CASE HAVE BOOSTED POPS UP ABOVE MOST GUIDANCE VALUES IN THOSE AREAS...BUT THEY ARE STILL ON THE LOW SIDE. THERE SHOULD BE SOME POTENTIAL FOR STRONG/SVR MICROBURSTS ASSUMING THAT STORMS DEVELOP GIVEN STEEPER LAPSE RATES (VERTICAL TOTALS ~27-28, 0-3KM LAPSE RATES > 8.5 DEG C/KM). WILL HOLD OFF ON ANY MENTION OF SEVERE POTENTIAL IN THE HAZARD PRODUCTS GIVEN VERY LIMITED COVERAGE. AS HAS BEEN ADVERTISED...HEAT STRESS WILL BECOME A BIGGER CONCERN GOING INTO MONDAY DUE TO THE INTENSIFYING RIDGE. FORECAST HEAT INDICES ARE EXPECTED TO APPROACH 105 BY MONDAY AFTN...SO WILL GO AHEAD AND FORMALLY INTRODUCE A LIMITED THREAT FOR DANGEROUS HEAT STRESS IN THE HWO/GRAPHICS. OTHERWISE...MORE ISOLATED/SCT DIURNAL TSTM ACTIVITY MAINLY OVER SOUTHERN PORTIONS OF THE ARKLAMISS CAN BE EXPECTED. MODELS SUGGEST THERE COULD BE GREATER INSTABILITY AND POTENTIAL FOR STRONG/SVR MICROBURST ACTIVITY WITH STORMS LIKELY NOT DISSIPATING UNTIL AFTER SUNSET IN HOT/HUMID AIRMASS. /EC/ TUESDAY THROUGH SATURDAY...THE SUBTROPICAL RIDGE WILL OVERALL REMAIN INTACT OVER THE CWA THROUGH MOST OF THE WORK WEEK. HOT AND HUMID CONDITIONS WILL PERSIST DURING THIS TIME AS HIGHS PEAK IN THE MID 90S AND DEW POINTS IN THE LOW TO MID 70S. THIS MAY RESULT IN DANGEROUS HEAT INDICES DURING SEVERAL AFTERNOONS NEXT WEEK... PARTICULARLY TUESDAY AND WEDNESDAY AFTERNOON....AS THEY`RE PROGGED TO RANGE BETWEEN 100-105F. THUS...I`LL MAINTAIN THE "LIMITED" POTENTIAL FOR AFTERNOON HEAT INDICES REACHING TO NEAR 105F IN THE HWO FOR BOTH TUESDAY AND WEDNESDAY AFTERNOONS. OF COURSE... THIS COULD BE EXPANDED FOR LATER IN THE WEEK IF NEEDED. WITH ALL THAT SAID...THIS LEVEL OF HEAT WILL BE MONITORED DURING THE PERIOD AS HEAT ADVISORIES MAY BE NEEDED FOR PORTIONS OF THE AREA. RAIN CHANCES WILL BE CONFINED TO THE AFTERNOON AND EARLY EVENING HOURS. MODELS CONTINUE TO SUGGEST THAT EASTERLY FLOW SOUTH OF THE AFOREMENTIONED RIDGE COULD INTERACT WITH CONVECTION ALONG THE SEABREEZE TUESDAY. THIS COULD POTENTIALLY HELP TO INCREASE THE COVERAGE OF CONVECTION OVER THE SOUTHERN AND CENTRAL PORTIONS OF THE FORECAST AREA DURING THIS TIME. HENCE...THE BEST RAIN CHANCES DURING THE PERIOD CURRENTLY LOOK TO FALL ON TUESDAY AFTERNOON. AS FRIDAY AND SATURDAY ROLL AROUND...MODELS ARE CURRENTLY IN AGREEMENT THAT THE RIDGE WILL BEGIN TO RETROGRADE BACK WEST OF THE REGION. THIS WILL ALLOW A TROUGH TO BEGIN DIGGING SOUTH AND INTO THE DEEP SOUTH DURING NEXT WEEKEND. /19/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 94 75 95 74 / 18 18 15 15 MERIDIAN 94 72 95 72 / 26 26 15 15 VICKSBURG 92 74 95 74 / 24 24 12 11 HATTIESBURG 94 75 95 75 / 26 26 27 23 NATCHEZ 92 74 93 75 / 26 26 22 20 GREENVILLE 93 75 96 75 / 17 12 11 6 GREENWOOD 94 74 96 75 / 10 10 14 9 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ 22/26/EC/19
AREA FORECAST DISCUSSION
NWS JACKSON MS
451 AM CDT SUN JUN 21 2015 .DISCUSSION... TODAY THROUGH MONDAY NIGHT... THE SUBTROPICAL RIDGE WILL GRADUALLY BUILD OVER THE ARKLAMISS AS WE GO THROUGH EARLY THIS WEEK...EVENTUALLY PEAKING OVER THE AREA LATER IN THE WEEK. IN THE NEAR TERM...A WEAKNESS IN THE RIDGE JUST WEST OF THE ARKLAMISS WILL HELP TO DRAW DEEP LAYER MOISTURE NORTHWARD. THIS HIGH PRECIPITABLE WATER AIR WILL CIRCULATE THROUGH THE RIDGE AND HELP TO INCREASE DIURNAL CONVECTIVE POTENTIAL IN SPITE OF MOSTLY SUBSIDENT ANTI-CYCLONIC FLOW. THE MAIN FOCUS FOR CONVECTIVE POTENTIAL LATE THIS AFTN/EVNG SHOULD BE OVER THE PINE BELT WHERE COASTAL CONVERGENCE AND LESS RIDGE INFLUENCE WILL BE FELT...A ALONG/W OF THE MS RIVER IN CLOSER PROXIMITY TO RIDGE WEAKNESS. THE SPC SSEO REFLECTS THIS GENERAL PATTERN AS DOES THE HRRR...ALTHOUGH THE HRRR SEEMS A BIT TOO GENEROUS WITH COVERAGE. IN ANY CASE HAVE BOOSTED POPS UP ABOVE MOST GUIDANCE VALUES IN THOSE AREAS...BUT THEY ARE STILL ON THE LOW SIDE. THERE SHOULD BE SOME POTENTIAL FOR STRONG/SVR MICROBURSTS ASSUMING THAT STORMS DEVELOP GIVEN STEEPER LAPSE RATES (VERTICAL TOTALS ~27-28, 0-3KM LAPSE RATES > 8.5 DEG C/KM). WILL HOLD OFF ON ANY MENTION OF SEVERE POTENTIAL IN THE HAZARD PRODUCTS GIVEN VERY LIMITED COVERAGE. AS HAS BEEN ADVERTISED...HEAT STRESS WILL BECOME A BIGGER CONCERN GOING INTO MONDAY DUE TO THE INTENSIFYING RIDGE. FORECAST HEAT INDICES ARE EXPECTED TO APPROACH 105 BY MONDAY AFTN...SO WILL GO AHEAD AND FORMALLY INTRODUCE A LIMITED THREAT FOR DANGEROUS HEAT STRESS IN THE HWO/GRAPHICS. OTHERWISE...MORE ISOLATED/SCT DIURNAL TSTM ACTIVITY MAINLY OVER SOUTHERN PORTIONS OF THE ARKLAMISS CAN BE EXPECTED. MODELS SUGGEST THERE COULD BE GREATER INSTABILITY AND POTENTIAL FOR STRONG/SVR MICROBURST ACTIVITY WITH STORMS LIKELY NOT DISSIPATING UNTIL AFTER SUNSET IN HOT/HUMID AIRMASS. /EC/ TUESDAY THROUGH SATURDAY... THE SUBTROPICAL RIDGE WILL OVERALL REMAIN INTACT OVER THE CWA THROUGH MOST OF THE WORK WEEK. HOT AND HUMID CONDITIONS WILL PERSIST DURING THIS TIME AS HIGHS PEAK IN THE MID 90S AND DEW POINTS IN THE LOW TO MID 70S. THIS MAY RESULT IN DANGEROUS HEAT INDICES DURING SEVERAL AFTERNOONS NEXT WEEK...PARTICULARLY TUESDAY AND WEDNESDAY AFTERNOON....AS THEY`RE PROGGED TO RANGE BETWEEN 100-105F. THUS...I`LL MAINTAIN THE "LIMITED" POTENTIAL FOR AFTERNOON HEAT INDICES REACHING TO NEAR 105F IN THE HWO FOR BOTH TUESDAY AND WEDNESDAY AFTERNOONS. OF COURSE... THIS COULD BE EXPANDED FOR LATER IN THE WEEK IF NEEDED. WITH ALL THAT SAID...THIS LEVEL OF HEAT WILL BE MONITORED DURING THE PERIOD AS HEAT ADVISORIES MAY BE NEEDED FOR PORTIONS OF THE AREA. RAIN CHANCES WILL BE CONFINED TO THE AFTERNOON AND EARLY EVENING HOURS. MODELS CONTINUE TO SUGGEST THAT EASTERLY FLOW SOUTH OF THE AFOREMENTIONED RIDGE COULD INTERACT WITH CONVECTION ALONG THE SEABREEZE TUESDAY. THIS COULD POTENTIALLY HELP TO INCREASE THE COVERAGE OF CONVECTION OVER THE SOUTHERN AND CENTRAL PORTIONS OF THE FORECAST AREA DURING THIS TIME. HENCE...THE BEST RAIN CHANCES DURING THE PERIOD CURRENTLY LOOK TO FALL ON TUESDAY AFTERNOON. AS FRIDAY AND SATURDAY ROLL AROUND...MODELS ARE CURRENTLY IN AGREEMENT THAT THE RIDGE WILL BEGIN TO RETROGRADE BACK WEST OF THE REGION. THIS WILL ALLOW A TROUGH TO BEGIN DIGGING SOUTH AND INTO THE DEEP SOUTH DURING NEXT WEEKEND. /19/ && .AVIATION...STRATUS AND PATCHY AREAS OF FOG WILL BE LESS PREVALENT THIS MORNING THAN IN RECENT DAYS GIVEN LIGHTER AND MORE WESTERLY FLOW AS THE RIDGE BUILDS OVER THE REGION. EXPECT VFR CONDITIONS TO PREVAIL FOR THE MOST PART TODAY THROUGH TONIGHT WITH LIMITED TSRA COVERAGE MAINLY ALONG AND SOUTH OF THE JAN/HKS/MEI CORRIDOR. /EC/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 94 75 95 74 / 18 18 15 15 MERIDIAN 94 72 95 72 / 26 26 15 15 VICKSBURG 93 74 95 74 / 24 24 12 11 HATTIESBURG 94 75 95 75 / 26 26 27 23 NATCHEZ 92 74 93 75 / 26 26 22 20 GREENVILLE 93 75 96 75 / 12 12 11 6 GREENWOOD 94 74 96 75 / 10 10 14 9 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ EC/19/
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
519 PM CDT Sun Jun 21 2015 .DISCUSSION... Issued at 518 PM CDT SUN JUN 21 2015 Tonight - Monday: Elevated convection redeveloping across northwest MO where airmass is being feed by increasing feed of accas forming across northeast KS. While the HRRR has had some issues its also been adamant that scattered convection would from over northwest MO late this afternoon and evening. SPC Meso Analysis depicts region of deep moisture convergence and advection of better instability into northwest MO to support the continued development. Isolated severe is possible as 40kt 0-6km shear supports activity. Convection will likely begin to fall apart as we head towards sunset and instability begins to wane. Boundary currently over west central MO will eventually lift north and into IA overnight allowing southerly flow to reestablish itself. Hot and humid air funnels back into the region as a stiff southwesterly low level jet pushes in. Hot h7 temperatures in the +14C to +17C range will effectively cap the airmass for most of the day. Highs should rebound back into the lower to middle 90s with hottest air over west central/northwest MO and eastern KS. Add in surface dewpoints in the 71F-74F range and HI values will likely top out around 105F. So issued a heat advisory for afternoon hours. Fast zonal flow across the northern tier of states will allow a fast moving shortwave to force a cold front south and east into northwest MO by very late afternoon. Hot h7 temperatures will hold back convection but operational models "cooling" at h7 by 00z Tuesday suggest cooling due to convection. While convection will likely hold off until Monday night will transition to that with a small window of slight chance PoPs over far northwest MO. Monday night - Tuesday night: Aforementioned cold front will be the focus for scattered convection Monday evening. Moderate/extreme instability and 0-6km bulk shear of 30-35kt will support a severe threat across northern MO down to the MO River. This frontal boundary is expected to stall across central MO on Tuesday then lift back north as a warm front. Thus this boundary will once again be the focus for a third round of potential severe weather Tuesday through Tuesday night. Should see a 10-15 degree thermal contrast across the boundary. High precipitable water values during this period will support a continued heavy rain threat as some training of cells is possible. Wednesday: The warm front is expected to lift north into IA and allow the cap to reform and give us a chance to dry out. But the hot and humid air is the trade off. Thursday - Saturday: The bouncing front is expected to head back south during this period and in the vicinity of the CWA such that moderately high PoPs are required. Extensive cloud cover and the rain cooled air should bring reasonably cool air to the region, but at a cost...high humidity and the threat of heavy rains. Wednesday - && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1235 PM CDT SUN JUN 21 2015 Vicinity thunderstorms currently keep bubbling up near the terminals and will persist well into the afternoon hours. This will likely result in a combination of VFR and MVFR ceilings as the storms move through this afternoon with the potential for quick periods of IFR. After the storms dissipate later today expect VFR conditions into the evening hours before the strong winds ahead of an approaching cold front advect some MVFR ceilings in late tonight. Ceilings should clear out tomorrow morning as the gusty winds increase in speed from the southwest. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...HEAT ADVISORY from 1 PM to 7 PM CDT Monday FOR KSZ025-057- 102>105. MO...HEAT ADVISORY from 1 PM to 7 PM CDT Monday FOR MOZ002>006- 011>015-020>023-028>031-037-038-043. && $$ DISCUSSION...MJ AVIATION...Cutter
AREA FORECAST DISCUSSION...UPDATED
NWS SPRINGFIELD MO
1230 PM CDT Sun Jun 21 2015 ...Updated Aviation and Mesoscale discussions... .MESOSCALE DISCUSSION... Issued at 1230 PM CDT SUN JUN 21 2015 A severe thunderstorm watch has been issued just to the north of the area through 5 PM. As mentioned in the previous update, the bulk of the expected thunderstorm activity will remain to our north, but a few storms will be possible across the northern portion of the outlook area (mainly central Missouri from Warsaw to Vichy and points north). Will maintain a limited risk for wind and hail given available instability and adjust further as conditions evolve. At the very least, folks in/around the Lake of the Ozarks region should remain aware of the risk for lightning this afternoon. && .UPDATE... Issued at 1135 AM CDT SUN JUN 21 2015 Continuing to watch convection fire along a low level boundary across central Missouri back into northeastern Kansas. This boundary really does not look to move much today, as a result it appears that the bulk of this activity may remain just to the north of our outlook area, but certainly close enough to keep a very close watch. At this time, convection is discreet. Cell motion (as estimated by 0-10km layer wind) is to the east southeast at about 25-30kt. If a cold pool can develop, forecast system motion is more to the southeast, so system organization will definitely bear watching. Plenty of instability will be feeding the boundary today, with shear increasing a bit as a shortwave passing to our north increases mid level westerlies. Discreet storms look to be the preferred storm mode heading into the afternoon. As a result, lightning, hail and localized wind gusts are the primary concerns with any activity that can get into the northern portion of the outlook area. If a cold pool can get organized, the wind risk will increase appreciably. Otherwise, expect a warm and humid first day of summer. A near carbon copy to yesterday with highs a few degrees either side of 90. && .SHORT TERM...(Today and Tonight) It was a typical June night over extreme southeast Kansas and the Missouri Ozarks. Temperatures had cooled into the lower 70s, under mostly clear skies and light southwesterly breezes. A complex of thunderstorms were ongoing across northeast Missouri. This feature threw an outflow boundary to the southwest, which was moving into central Missouri. Convection was not developing along the outflow, due to dry air in the mid levels, and strong convective inhibition present within the Ozarks lower trop. The hi-res ARW and NMM suggest that convection will eventually fire along this boundary by 9-12z this morning. The HRRR along with several other models keeps the Ozarks dry today. Given the 00z RAOB from last night, we will keep the forecast dry through today, for the exception of some low end pops in central Missouri. Look for temperatures to warm into the upper 80s and lower 90s today. .LONG TERM...(Monday through Saturday) The summertime high attempts to build over the nation`s midsection Monday through Thursday. This will bring sunshine, humidity, and hot temperatures. Look for temperatures to range from the upper 80s to the lower 90s on an afternoon basis through Thursday. The periphery of the summertime high will act as a storm track for a series of shortwave troughs. This storm track will reside across northern Missouri or southern Iowa, so we will need to watch any convection that may attempt to sneak into central Missouri. Right now we`re going to keep precipitation chances in central Missouri very conservative through Thursday. All other locations south of Highway 54 can expect hot and dry weather through Thursday. By Thursday night or Friday, the summer high re-positions across the Mountain West, forcing northwest flow and a cold front into southern Missouri. This will not only cool temperatures off, but also bring our next widespread chance for showers and thunderstorms. Both the GFS and the ECMWF suggests precipitation chances to continue through the upcoming weekend. It`s a little ways out to get too specific about details, but we`ll have some chances going in the forecast. && .AVIATION...(For the 18Z TAFS through 18Z Monday Afternoon) Issued at 1230 PM CDT SUN JUN 21 2015 Overall, VFR conditions are expected for the next 24 hours and beyond. Complexes of thunderstorms to the north and south of the TAF sites will produce variable cloud cover, ranging from diurnal cumulus to cirrus. Southwest winds will be gusty this afternoon and again Monday morning. Tonight, a strengthening low level jet will produce low level wind shear. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ MESOSCALE...Gagan UPDATE...Gagan SHORT TERM...Cramer LONG TERM...Cramer AVIATION...Gagan
AREA FORECAST DISCUSSION...UPDATED
NWS SPRINGFIELD MO
1136 AM CDT Sun Jun 21 2015 .UPDATE... Issued at 1135 AM CDT SUN JUN 21 2015 Continuing to watch convection fire along a low level boundary across central Missouri back into northeastern Kansas. This boundary really does not look to move much today, as a result it appears that the bulk of this activity may remain just to the north of our outlook area, but certainly close enough to keep a very close watch. At this time, convection is discreet. Cell motion (as estimated by 0-10km layer wind) is to the east southeast at about 25-30kt. If a cold pool can develop, forecast system motion is more to the southeast, so system organization will definitely bear watching. Plenty of instability will be feeding the boundary today, with shear increasing a bit as a shortwave passing to our north increases mid level westerlies. Discreet storms look to be the preferred storm mode heading into the afternoon. As a result, lightning, hail and localized wind gusts are the primary concerns with any activity that can get into the northern portion of the outlook area. If a cold pool can get organized, the wind risk will increase appreciably. Otherwise, expect a warm and humid first day of summer. A near carbon copy to yesterday with highs a few degrees either side of 90. && .SHORT TERM...(Today and Tonight) It was a typical June night over extreme southeast Kansas and the Missouri Ozarks. Temperatures had cooled into the lower 70s, under mostly clear skies and light southwesterly breezes. A complex of thunderstorms were ongoing across northeast Missouri. This feature threw an outflow boundary to the southwest, which was moving into central Missouri. Convection was not developing along the outflow, due to dry air in the mid levels, and strong convective inhibition present within the Ozarks lower trop. The hi-res ARW and NMM suggest that convection will eventually fire along this boundary by 9-12z this morning. The HRRR along with several other models keeps the Ozarks dry today. Given the 00z RAOB from last night, we will keep the forecast dry through today, for the exception of some low end pops in central Missouri. Look for temperatures to warm into the upper 80s and lower 90s today. .LONG TERM...(Monday through Saturday) The summertime high attempts to build over the nation`s midsection Monday through Thursday. This will bring sunshine, humidity, and hot temperatures. Look for temperatures to range from the upper 80s to the lower 90s on an afternoon basis through Thursday. The periphery of the summertime high will act as a storm track for a series of shortwave troughs. This storm track will reside across northern Missouri or southern Iowa, so we will need to watch any convection that may attempt to sneak into central Missouri. Right now we`re going to keep precipitation chances in central Missouri very conservative through Thursday. All other locations south of Highway 54 can expect hot and dry weather through Thursday. By Thursday night or Friday, the summer high re-positions across the Mountain West, forcing northwest flow and a cold front into southern Missouri. This will not only cool temperatures off, but also bring our next widespread chance for showers and thunderstorms. Both the GFS and the ECMWF suggests precipitation chances to continue through the upcoming weekend. It`s a little ways out to get too specific about details, but we`ll have some chances going in the forecast. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 618 AM CDT SUN JUN 21 2015 For the KSGF/KJLN/KBBG tafs: VFR conditions are expected. Low pressure moving out into the central Plains will keep dry s-sw sfc winds in place. Progged low level wind fields support a marginal mention of low level wind shear again late in the taf period. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ UPDATE...Gagan SHORT TERM...Cramer LONG TERM...Cramer AVIATION...DSA
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
619 AM CDT Sun Jun 21 2015 .SHORT TERM...(Today and Tonight) It was a typical June night over extreme southeast Kansas and the Missouri Ozarks. Temperatures had cooled into the lower 70s, under mostly clear skies and light southwesterly breezes. A complex of thunderstorms were ongoing across northeast Missouri. This feature threw an outflow boundary to the southwest, which was moving into central Missouri. Convection was not developing along the outflow, due to dry air in the mid levels, and strong convective inhibition present within the Ozarks lower trop. The hi-res ARW and NMM suggest that convection will eventually fire along this boundary by 9-12z this morning. The HRRR along with several other models keeps the Ozarks dry today. Given the 00z RAOB from last night, we will keep the forecast dry through today, for the exception of some low end pops in central Missouri. Look for temperatures to warm into the upper 80s and lower 90s today. .LONG TERM...(Monday through Saturday) The summertime high attempts to build over the nation`s midsection Monday through Thursday. This will bring sunshine, humidity, and hot temperatures. Look for temperatures to range from the upper 80s to the lower 90s on an afternoon basis through Thursday. The periphery of the summertime high will act as a storm track for a series of shortwave troughs. This storm track will reside across northern Missouri or southern Iowa, so we will need to watch any convection that may attempt to sneak into central Missouri. Right now we`re going to keep precipitation chances in central Missouri very conservative through Thursday. All other locations south of Highway 54 can expect hot and dry weather through Thursday. By Thursday night or Friday, the summer high re-positions across the Mountain West, forcing northwest flow and a cold front into southern Missouri. This will not only cool temperatures off, but also bring our next widespread chance for showers and thunderstorms. Both the GFS and the ECMWF suggests precipitation chances to continue through the upcoming weekend. It`s a little ways out to get too specific about details, but we`ll have some chances going in the forecast. && .AVIATION...(For the 12Z TAFS through 12Z Monday Morning) Issued at 618 AM CDT SUN JUN 21 2015 For the KSGF/KJLN/KBBG tafs: VFR condtions are expected. Low pressure moving out into the central Plains will keep dry s-sw sfc winds in place. Progged low level wind fields support a marginal mention of low level wind shear again late in the taf period. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Cramer LONG TERM...Cramer AVIATION...DSA
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
243 AM CDT Sun Jun 21 2015 .SHORT TERM...(Today and Tonight) It was a typical June night over extreme southeast Kansas and the Missouri Ozarks. Temperatures had cooled into the lower 70s, under mostly clear skies and light southwesterly breezes. A complex of thunderstorms were ongoing across northeast Missouri. This feature threw an outflow boundary to the southwest, which was moving into central Missouri. Convection was not developing along the outflow, due to dry air in the mid levels, and strong convective inhibition present within the Ozarks lower trop. The hi-res ARW and NMM suggest that convection will eventually fire along this boundary by 9-12z this morning. The HRRR along with several other models keeps the Ozarks dry today. Given the 00z RAOB from last night, we will keep the forecast dry through today, for the exception of some low end pops in central Missouri. Look for temperatures to warm into the upper 80s and lower 90s today. .LONG TERM...(Monday through Saturday) The summertime high attempts to build over the nation`s midsection Monday through Thursday. This will bring sunshine, humidity, and hot temperatures. Look for temperatures to range from the upper 80s to the lower 90s on an afternoon basis through Thursday. The periphery of the summertime high will act as a storm track for a series of shortwave troughs. This storm track will reside across northern Missouri or southern Iowa, so we will need to watch any convection that may attempt to sneak into central Missouri. Right now we`re going to keep precipitation chances in central Missouri very conservative through Thursday. All other locations south of Highway 54 can expect hot and dry weather through Thursday. By Thursday night or Friday, the summer high re-positions across the Mountain West, forcing northwest flow and a cold front into southern Missouri. This will not only cool temperatures off, but also bring our next widespread chance for showers and thunderstorms. Both the GFS and the ECMWF suggests precipitation chances to continue through the upcoming weekend. It`s a little ways out to get too specific about details, but we`ll have some chances going in the forecast. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 1118 PM CDT SAT JUN 20 2015 Low level wind shear will be the main concern for the terminals through tonight, as a fairly strong low level jet overspreads the region. Southwest winds will then become gusty by mid morning on Sunday, continuing through sunset. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Cramer LONG TERM...Cramer AVIATION...Boxell
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
1035 AM MDT SUN JUN 21 2015 .UPDATE... CHANGES MADE THIS MORNING WERE MINOR AND MAINLY FOR COLLABORATION PURPOSES. DID RAISE POPS A BIT OVER THE FAR NORTHEAST AS SOME HIGH RESOLUTION MODELS WERE INITIATING CONVECTION AGGRESSIVELY OUT THERE. ALSO RAISED POPS SOME OVER THE WEST AS SHORTWAVE RAPIDLY APPROACHING. EASTERN STORMS HAVE A GOOD CHANCE OF BECOMING SEVERE QUICKLY WITH DEEP CAPE AND STRONG SHEAR. THE WEST COULD HAVE SOME STRONG STORMS TOO...BUT MAINLY ISSUE THERE WILL BE WIND WITH DRY LOWER LEVELS. MOST OF THE WESTERN STORMS WILL TRACK NORTHEAST AND SOME MODELS KEEP THE BRUNT OF THE ACTIVITY NORTH. A STRONG COLD FRONT WILL PUSH IN TONIGHT AND THIS COULD BE ENHANCED BY CONVECTION OVER THE NORTH FOR STRONG OUTFLOW WINDS. TWH && .SHORT TERM...VALID FOR TDY AND MON... QUIET WEATHER ACROSS OUR CWA EARLY THIS MORNING AS WE REMAIN UNDER THE INFLUENCE OF FLAT UPPER LEVEL RIDGING...WITH CONVECTION AT NOSE OF LOW LEVEL JET STILL DEVELOPING TO OUR SOUTHEAST FROM NORTHEAST WY INTO SOUTHWEST SD. WATER VAPOR IMAGERY SHOWS A COUPLE FEATURES OF INTEREST...ONE SHORTWAVE MOVING INTO OR AND ANOTHER IN SOUTHERN BC. THESE WAVES WILL PARTIALLY PHASE TOGETHER AND BRING US A GOOD CHANCE OF SHOWERS AND TSTMS LATER TODAY THROUGH TONIGHT. POTENTIAL EXISTS FOR SEVERE STORMS IN OUR EAST THIS AFTERNOON MAINLY ALONG AND EAST OF A MILES CITY TO ALZADA LINE. MOIST ADVECTION ALREADY OCCURRING PER SOUTHEASTERLY FLOW UP THE HIGH PLAINS WITH LATEST ANALYSIS SHOWING PWATS TO AN INCH IN SOUTHEAST MT. WEAK MID LEVEL SHORTWAVE AND SFC WARM FRONT WILL PUSH ACROSS OUR CWA THIS MORNING. THOUGH THE BOUNDARY LAYER WILL BECOME WELL- MIXED AND DRIER ACROSS OUR WEST AND CENTRAL PARTS...MOISTURE AND INSTABILITY WILL BECOME DEEPER EAST OF SFC TROF. LATEST HRRR RUNS SEEM VERY REASONABLE IN DEVELOPING CONVECTION IN OUR FAR EAST BY AROUND 19Z AS CAPES BUILD TO 1500+ J/KG. INSTABILITY AND PLENTIFUL EFFECTIVE BULK SHEAR ARE SUGGESTIVE OF SEVERE STORMS IN THIS AREA THROUGH AROUND 00Z...BY WHICH THE PRE-FRONTAL SFC TROF SHOULD SHIFT INTO THE WESTERN DAKOTAS. LARGE HAIL AND DAMAGING WINDS ARE MAIN THREATS BUT CANNOT RULE OUT A TORNADO EITHER ESPECIALLY IF SFC DEW PTS CLIMB TO NEAR 60F. AGAIN THIS POTENTIAL IS IN OUR FAR EAST AND STORMS MAY INITIATE AS EARLY AS 19Z. OTHER AREA OF CONCERN IS OUR WEST AS SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING AS LARGE SCALE ASCENT INCREASES IN COMBINATION W/ A COLD FRONTAL PASSAGE. MAIN RISK IN OUR WEST WILL BE WIND PER FRONTAL PUSH AND DEEPLY MIXED PRE- FRONTAL BOUNDARY LAYER...IE A COMBINATION OF CONVECTIVE AND FRONTAL WINDS...THOUGH CANNOT RULE OUT SMALL HAIL AS WELL. FRONT IS EXPECTED TO IMPACT LVM-3HT BY LATE AFTERNOON THEN BIL/SHR DURING THE EVENING. WILL CONTINUE TO HIGHLIGHT ALL OF THESE POTENTIAL IMPACTS IN HWO AND GRAPHIC. TEMPS TODAY WILL CLIMB INTO THE 80S IN PRE-FRONTAL REGIME...WITH HIGHS BACK DOWN TO THE MID TO UPPER 70S MONDAY. COULD SEE SOME AFTERNOON/EVENING SHOWERS AND WEAKER STORMS IN OUR WEST TOMORROW. ACTIVITY MAY SPREAD TO OUR SOUTHEAST BY LATE MONDAY NIGHT AS NEXT AREA OF PV COMES OFF THE PACIFIC AND SOUTHEASTERLY LOW LEVEL JET BEGINS TO ADVECT MOISTURE BACK TO SOUTHEAST MT. NO SEVERE WX ANTICIPATED MONDAY OR MONDAY NIGHT. JKL .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... EXTENDED FORECAST PERIOD KEEPS AN UNSETTLED BUT WARM ZONAL FLOW ACROSS THE AREA TUESDAY INTO FRIDAY WHICH WILL MAINTAIN THE CHANCES FOR THUNDERSTORM ACTIVITY A FEW DAYS LATER THAN PREVIOUSLY INDICATED. MODELS SHOW EPISODES OF EASTERLY FLOW AT THE LOW LEVELS DURING THIS PERIOD WHICH WILL PROVIDE HIGHER DEWPOINTS SUPPORTING THE THUNDERSTORMS. TIMING AND STRENGTH OF SHORTWAVES DURING THIS PERIOD IS LESS CERTAIN BUT HAVE THUNDERSTORMS MENTIONED EACH DAY AND WILL HAVE TO WATCH CAPE VALUES TO SEE IF SEVERE WEATHER WILL BE POSSIBLE. TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL DURING THE PERIOD IN THE MID 80S FOR MOST PLACES. MODELS SHOWING THE RIDGE BEGINNING TO ASSERT ITS INFLUENCE FOR SATURDAY AND SUNDAY OVER WESTERN MONTANA WHICH LOOKS TO DISRUPT THE LOW LEVEL EASTERLY FLOW FOR MOST OF THE AREA. PREVIOUSLY ADVERTISED WARMUP LOOKS A BIT SLOWER BUT STILL SHOULD BEGIN TO APPROACH 90 BY SUNDAY...POSSIBLY SATURDAY FOR A FEW AREAS. WILL SEE A DRYING TREND DURING THE WEEKEND. BORSUM && .AVIATION... VFR CONDITIONS WILL PREVAIL THROUGH THE MORNING. THUNDERSTORMS WILL INITIATE OVER THE WESTERN HIGH TERRAIN AFTER 21Z AND OTHER THUNDERSTORMS WILL DEVELOP OVER THE NE ZONES...FROM KMLS TO KBHK. THE STORMS OVER THE TERRAIN WILL PROGRESS E FROM 21Z TO 00Z THROUGH KLVM AND KBIL AS A COLD FRONT DROPS DOWN FROM THE N. HAIL AND STRONG WIND GUSTS ARE POSSIBLE WITH THE STORMS FROM KLVM TO KBIL...WHILE LARGE HAIL AND DAMAGING WINDS ARE POSSIBLE WITH STORMS OVER KMLS AND KBHK. STORMS WILL BECOME MORE WIDESPREAD THIS EVENING AS THE COLD FRONT DROPS S. WINDS WILL BE STRONG AND GUSTY ACROSS THE ENTIRE AREA TONIGHT. THE STORMS OVER SE MT MAY CONTAIN LARGE HAIL AND DAMAGING WINDS THROUGH THE EVENING. ARTHUR && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 086 055/078 056/081 057/083 060/090 063/088 062/086 2/T 41/B 23/T 32/T 21/B 11/U 11/U LVM 084 048/077 050/081 050/084 053/090 055/089 054/087 3/T 42/T 33/T 32/T 21/B 11/U 11/U HDN 088 054/080 055/083 058/085 060/092 062/089 061/087 1/B 31/B 33/T 33/T 21/B 11/B 11/U MLS 087 057/078 057/081 057/082 059/087 060/086 060/083 2/T 51/B 33/T 33/T 22/T 22/T 21/U 4BQ 086 055/077 056/079 056/081 059/087 061/087 059/083 2/T 31/B 43/T 43/T 32/T 22/T 21/U BHK 083 054/075 054/078 055/078 056/082 059/082 056/079 4/T 52/T 23/T 44/T 33/T 33/T 32/T SHR 086 052/076 052/079 053/080 054/087 057/086 056/082 1/B 20/B 23/T 32/T 22/T 22/T 21/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BILLINGS MT
256 AM MDT SUN JUN 21 2015 .SHORT TERM...VALID FOR TDY AND MON... QUIET WEATHER ACROSS OUR CWA EARLY THIS MORNING AS WE REMAIN UNDER THE INFLUENCE OF FLAT UPPER LEVEL RIDGING...WITH CONVECTION AT NOSE OF LOW LEVEL JET STILL DEVELOPING TO OUR SOUTHEAST FROM NORTHEAST WY INTO SOUTHWEST SD. WATER VAPOR IMAGERY SHOWS A COUPLE FEATURES OF INTEREST...ONE SHORTWAVE MOVING INTO OR AND ANOTHER IN SOUTHERN BC. THESE WAVES WILL PARTIALLY PHASE TOGETHER AND BRING US A GOOD CHANCE OF SHOWERS AND TSTMS LATER TODAY THROUGH TONIGHT. POTENTIAL EXISTS FOR SEVERE STORMS IN OUR EAST THIS AFTERNOON MAINLY ALONG AND EAST OF A MILES CITY TO ALZADA LINE. MOIST ADVECTION ALREADY OCCURRING PER SOUTHEASTERLY FLOW UP THE HIGH PLAINS WITH LATEST ANALYSIS SHOWING PWATS TO AN INCH IN SOUTHEAST MT. WEAK MID LEVEL SHORTWAVE AND SFC WARM FRONT WILL PUSH ACROSS OUR CWA THIS MORNING. THOUGH THE BOUNDARY LAYER WILL BECOME WELL- MIXED AND DRIER ACROSS OUR WEST AND CENTRAL PARTS...MOISTURE AND INSTABILITY WILL BECOME DEEPER EAST OF SFC TROF. LATEST HRRR RUNS SEEM VERY REASONABLE IN DEVELOPING CONVECTION IN OUR FAR EAST BY AROUND 19Z AS CAPES BUILD TO 1500+ J/KG. INSTABILITY AND PLENTIFUL EFFECTIVE BULK SHEAR ARE SUGGESTIVE OF SEVERE STORMS IN THIS AREA THROUGH AROUND 00Z...BY WHICH THE PRE-FRONTAL SFC TROF SHOULD SHIFT INTO THE WESTERN DAKOTAS. LARGE HAIL AND DAMAGING WINDS ARE MAIN THREATS BUT CANNOT RULE OUT A TORNADO EITHER ESPECIALLY IF SFC DEW PTS CLIMB TO NEAR 60F. AGAIN THIS POTENTIAL IS IN OUR FAR EAST AND STORMS MAY INITIATE AS EARLY AS 19Z. OTHER AREA OF CONCERN IS OUR WEST AS SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON AND EVENING AS LARGE SCALE ASCENT INCREASES IN COMBINATION W/ A COLD FRONTAL PASSAGE. MAIN RISK IN OUR WEST WILL BE WIND PER FRONTAL PUSH AND DEEPLY MIXED PRE- FRONTAL BOUNDARY LAYER...IE A COMBINATION OF CONVECTIVE AND FRONTAL WINDS...THOUGH CANNOT RULE OUT SMALL HAIL AS WELL. FRONT IS EXPECTED TO IMPACT LVM-3HT BY LATE AFTERNOON THEN BIL/SHR DURING THE EVENING. WILL CONTINUE TO HIGHLIGHT ALL OF THESE POTENTIAL IMPACTS IN HWO AND GRAPHIC. TEMPS TODAY WILL CLIMB INTO THE 80S IN PRE-FRONTAL REGIME...WITH HIGHS BACK DOWN TO THE MID TO UPPER 70S MONDAY. COULD SEE SOME AFTERNOON/EVENING SHOWERS AND WEAKER STORMS IN OUR WEST TOMORROW. ACTIVITY MAY SPREAD TO OUR SOUTHEAST BY LATE MONDAY NIGHT AS NEXT AREA OF PV COMES OFF THE PACIFIC AND SOUTHEASTERLY LOW LEVEL JET BEGINS TO ADVECT MOISTURE BACK TO SOUTHEAST MT. NO SEVERE WX ANTICIPATED MONDAY OR MONDAY NIGHT. JKL .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... EXTENDED FORECAST PERIOD KEEPS AN UNSETTLED BUT WARM ZONAL FLOW ACROSS THE AREA TUESDAY INTO FRIDAY WHICH WILL MAINTAIN THE CHANCES FOR THUNDERSTORM ACTIVITY A FEW DAYS LATER THAN PREVIOUSLY INDICATED. MODELS SHOW EPISODES OF EASTERLY FLOW AT THE LOW LEVELS DURING THIS PERIOD WHICH WILL PROVIDE HIGHER DEWPOINTS SUPPORTING THE THUNDERSTORMS. TIMING AND STRENGTH OF SHORTWAVES DURING THIS PERIOD IS LESS CERTAIN BUT HAVE THUNDERSTORMS MENTIONED EACH DAY AND WILL HAVE TO WATCH CAPE VALUES TO SEE IF SEVERE WEATHER WILL BE POSSIBLE. TEMPERATURES WILL BE SLIGHTLY ABOVE NORMAL DURING THE PERIOD IN THE MID 80S FOR MOST PLACES. MODELS SHOWING THE RIDGE BEGINNING TO ASSERT ITS INFLUENCE FOR SATURDAY AND SUNDAY OVER WESTERN MONTANA WHICH LOOKS TO DISRUPT THE LOW LEVEL EASTERLY FLOW FOR MOST OF THE AREA. PREVIOUSLY ADVERTISED WARMUP LOOKS A BIT SLOWER BUT STILL SHOULD BEGIN TO APPROACH 90 BY SUNDAY...POSSIBLY SATURDAY FOR A FEW AREAS. WILL SEE A DRYING TREND DURING THE WEEKEND. BORSUM && .AVIATION... MOSTLY CLEAR CONDITIONS TO START THE DAY WITH A FEW MID LEVEL CLOUDS. TWO AREAS OF THUNDERSTORM ACTIVITY ARE EXPECTED DURING THE AFTERNOON HOURS. DURING THE EARLY AFTERNOON SEVERE THUNDERSTORMS ARE EXPECTED ALONG AND EAST OF A KMLS TO K4BQ LINE WITH STORMS CAPABLE OF PRODUCING LARGE HAIL ALONG WITH VERY STRONG WINDS. A SECOND AREA OF THUNDERSTORMS WILL MOVE INTO THE WESTERN HALF OF THE FORECAST AREA DURING THE MID AFTERNOON HOURS WITH STORMS NOT AS INTENSE BUT ASSOCIATED WITH A COLD FRONT WHICH WILL BRING A THREAT OF STRONG WIND GUSTS. THESE STORMS WILL IMPACT KLVM AROUND 21Z AND REACH KBIL AROUND 23Z. BORSUM && .PRELIMINARY POINT TEMP/POPS... TDY MON TUE WED THU FRI SAT ------------------------------------------------------- BIL 086 055/078 056/081 057/083 060/090 063/088 062/086 2/T 41/B 23/T 32/T 21/B 11/U 11/U LVM 084 048/077 050/081 050/084 053/090 055/089 054/087 2/T 42/T 33/T 32/T 21/B 11/U 11/U HDN 088 054/080 055/083 058/085 060/092 062/089 061/087 1/B 31/B 33/T 33/T 21/B 11/B 11/U MLS 087 057/078 057/081 057/082 059/087 060/086 060/083 2/T 51/B 33/T 33/T 22/T 22/T 21/U 4BQ 086 055/077 056/079 056/081 059/087 061/087 059/083 2/T 31/B 43/T 43/T 32/T 22/T 21/U BHK 083 054/075 054/078 055/078 056/082 059/082 056/079 4/T 52/T 23/T 44/T 33/T 33/T 32/T SHR 086 052/076 052/079 053/080 054/087 057/086 056/082 1/B 20/B 23/T 32/T 22/T 22/T 21/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1258 AM CDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 324 PM CDT SAT JUN 20 2015 UPPER AIR AND SATELLITE DATA SHOW THE AREA SITTING UNDER GENERALLY ZONAL FLOW...AN AREA OF HIGH PRESSURE IS SETTLED OVER THE SWRN COAST...WHILE LOW PRESSURE SLIDES EAST ACROSS THE MIDWEST. ANOTHER SHORTWAVE DISTURBANCE IS MOVING ACROSS NRN MN INTO THE GREAT LAKES REGION...WITH IT BEING RESPONSIBLE FOR THE FRONTAL BOUNDARY ACROSS THE AREA. AS EXPECTED...THE FRONT HAS GRADUALLY SAGGED SOUTH THROUGH THE DAY...AND CURRENTLY SITS ACROSS THE FAR SERN CORNER OF THE CWA. STARTING AROUND MID MORNING...HAD A FEW ISOLATED SHOWERS AND RUMBLES OF THUNDER DEVELOP ALONG THE FRONT...ENDED UP THROWING SOME SLIGHT POPS IN THE FORECAST. SINCE THEN...HASNT BEEN ANY INCREASE IN ACTIVITY...WITH THE SPC MESO PAGE SHOWING CAPPING IN PLACE WITH 700MB TEMPS AROUND 14C. HASNT BEEN ANY SURPRISES WITH TEMPERATURES OR DPTS...WITH 3 PM OBS RANGING FROM THE LOWER 80S IN THE FAR NORTH TO MID 90S IN THE SOUTHEAST. HEAT INDEX VALUES HAVE REACH NEAR 100 IN THE FAR SOUTHEAST. THE RAP AND HRRR CONTINUE TO SHOW THAT LATE THIS AFTERNOON /BANKING ON A WEAKENING CAP/ THAT THUNDERSTORMS WILL DEVELOP ALONG THE FRONT ACROSS THE EXTREME SE CORNER OF THE CWA...AND WILL CONTINUE TO CARRY SOME SLIGHT POPS IN THAT AREA...OTHER MODELS SHOW NOTHING DEVELOPING. OUTSIDE OF THAT...THE EVENING HOURS ARE EXPECTED TO BE DRY. LATER TONIGHT AND INTO A PORTION OF THE DAY TOMORROW...CONTINUED TO CARRY THE POPS ACROSS ROUGHLY THE NRN HALF OF THE CWA...WITH MODELS SHOWING ANOTHER WEAK UPPER LEVEL SHORTWAVE DISTURBANCE MOVING OUT OF THE ROCKIES. LITTLE UNCERTAINTY WITH THE TIMING...AND OVERALL COVERAGE...WITH THE LATEST HRRR COMING IN WITH MORE ACTIVITY THAN BASICALLY ANY OTHER MODEL. WILL HAVE TO SEE HOW UPCOMING MODEL RUN TRENDS AND MONITOR ACTIVITY TO THE W/NW THIS EVENING...AND ADJUST AS NECESSARY. AT THIS POINT...KEPT THOSE POPS CONFINED TO AFTER 06Z...CONTINUING INTO THE FIRST HALF OF THE DAY TOMORROW...WITH A DRY AFTERNOON. AT THE SFC...EXPECTING HIGHER PRESSURE TO SETTLE IN ACROSS THE AREA TONIGHT...RESULTING IN LIGHTER WINDS...BUT BECOMING MORE E/SERLY WITH TIME. LOW PRESSURE BECOMES ORGANIZED TOMORROW OVER THE HIGH PLAINS...WITH THE POTENTIAL FOR A WARM FRONTAL BOUNDARY TO SET UP NEAR THE STATE LINE. MODELS SHOW THAT SERLY COMPONENT TO THE WINDS REMAINING MAINLY OVER NEB...WITH MORE SRLY WINDS OVER NC KS. AS FAR AS TEMPERATURES GO...CURRENT FORECAST CALLS FOR CONDITIONS SIMILAR TO TODAY...MID 80S IN THE NORTH...MID/UPPER 90S IN THE S/SW. LOOKING AT HEAT INDEX VALUES AROUND 100 AGAIN POSSIBLE ROUGHLY NEAR/SOUTH OF THE STATE LINE. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 324 PM CDT SAT JUN 20 2015 GUIDANCE SUGGESTS UPPER TROPOSPHERIC RIDGING WILL BE NOTED OVER THE WESTERN HALF OF THE CONUS TO START THE LONG-TERM FORECAST PERIOD AT 00 MONDAY. THIS RIDGE IS EXPECTED TO WEAKEN SOMEWHAT THROUGH WEDNESDAY...WITH A STRENGTHENING RIDGE ACROSS THE WESTERN CONUS EXPECTED THURSDAY ONWARD. AS A RESULT...QUASI-ZONAL TO AT TIME NORTHWESTERLY UPPER TROPOSPHERIC FLOW IS EXPECTED OVER OUR AREA MONDAY THROUGH WEDNESDAY...WITH INCREASINGLY NORTHWESTERLY FLOW THURSDAY ONWARD. STARTING WITH SUNDAY NIGHT INTO EARLY MONDAY MORNING...GUIDANCE CONTINUES SHIFTING ANY APPRECIABLE CHANCE AT PRECIPITATION TO THE NORTH/NORTHEAST OF OUR AREA...MORE ALONG THE PRIMARY AXIS OF ENHANCED UPPER TROPOSPHERIC FLOW. ALTHOUGH THE OPERATIONAL GFS DOES SUGGEST A VERY ISOLATED AREA ACROSS OUR FAR NORTHWESTERN CWA COULD SEE PRECIPITATION EARLY MONDAY MORNING...THIS OUTPUT IS THE OUTLIER WHEN COMPARED TO THE NAM AND EC WHICH BOTH KEEP ANY PRECIPITATION WELL TO OUR NORTH/NORTHEAST. GIVEN THIS...OPTED TO GO AHEAD WITH DRY CONDITIONS SUNDAY NIGHT INTO EARLY MONDAY MORNING. DRY CONDITIONS ALSO REMAIN IN THE FORECAST DURING THE DAY MONDAY AND MONDAY EVENING AS AN OVERALL LACK IN OMEGA PERSISTS ACROSS THE REGION. STARTING EARLY TUESDAY MORNING AND CONTINUING INTO THE DAY TUESDAY...A SUBTLE PERTURBATION ADVANCING EAST/NORTHEAST FROM THE MID ROCKIES...MOST EVIDENT NEAR 700MB PER MODEL GUIDANCE...COULD BRING OUR NEXT CHANCE FOR PRECIPITATION...ESPECIALLY ACROSS CENTRAL AND NORTHERN PORTIONS OF THE CWA. THIS IS A SOLUTION SUPPORTED BY QPF FIELDS FROM THE NAM AND OPERATIONAL GFS...AND TO A LESSER EXTENT THE EC. GIVEN THIS...OPTED TO GO AHEAD WITH 20-30% POPS ACROSS CENTRAL AND NORTHERN PORTIONS OF THE CWA EARLY TUESDAY MORNING THROUGH THE DAY TUESDAY. TUESDAY NIGHT AND BEYOND...AS PREVIOUSLY MENTIONED...INCREASING NORTHWESTERLY UPPER TROPOSPHERIC FLOW SHOULD DEVELOP OVER OUR AREA A THE WESTERN CONUS RIDGE STRENGTHENS...THUS INCREASING THE CHANCES FOR MULTIPLE SMALL-SCALE PERTURBATION TO CLEAR THE REGION. AS MENTIONED BY THE PREVIOUS SHIFT...CONFIDENCE WITH RESPECT TO THE REALIZATION OF PRECIPITATION ON ANY GIVEN DAY DURING THIS TIME PERIOD REMAINS LOW...BUT ITS HARD TO JUSTIFY A DRY FORECAST BASED ON MODEL GUIDANCE AND AS A RESULT...WENT AHEAD AND MAINTAINED POPS...GENERALLY IN THE 20-40% RANGE...ACROSS MUCH OF THE AREA TUESDAY NIGHT THROUGH SATURDAY. GUIDANCE SUGGESTS RESPECTABLE VALUES OF LOWER TROPOSPHERIC MOISTURE...WORKING IN CONCERT WITH VARYING LAPSE RATES WITH THE PASSAGE OF UPPER TROPOSPHERIC PERTURBATIONS...WILL PRESENT POTENTIAL ENERGY VALUES GENERALLY IN THE 1000-3000J/KG RANGE EACH DAY DURING THE LONG-TERM FORECAST PERIOD. DEEP-LAYER BULK SHEAR OF ~30KTS WILL ALSO BE POSSIBLE AS THE ENHANCED UPPER TROPOSPHERIC FLOW ESTABLISHES ITSELF OVER THE REGION. THAT SAID...FORECAST PROXIMITY SOUNDINGS FROM THE ACROSS THE CWA...PER THE NAM AND OPERATIONAL GFS...SUGGEST A HEALTHY LOWER TROPOSPHERIC CAPPING INVERSION WILL BE PRESENT EACH DAY AND WITH OMEGA REMAINING ON THE QUESTIONABLE SIDE...ITS HARD TO SAY THAT ANY ONE DAY HAS A GREATER CHANCE OF SEVERE WEATHER OVER THE NEXT. OBVIOUSLY...ANY DAY THAT CAN REALIZE CONVECTIVE INITIALIZATION WILL HAVE AT LEAST A CHANCE OF STRONG TO SEVERE THUNDERSTORM ACTIVITY...BUT CONFIDENCE IS NOT HIGH ENOUGH TO DEFINITIVELY MENTION SUCH CONDITIONS IN THE HWO. GIVEN THIS...FOR THE HWO...WILL SIMPLY STATE THAT SEVERE CONVECTION IS NOT OUT OF THE QUESTION DURING THE LONG-TERM FORECAST PERIOD...AND THE FORECAST WILL NEED TO BE MONITORED FOR THE POSSIBILITY OF SEVERE WEATHER DURING THE MIDDLE TO LATE PART OF NEXT WEEK. PRE-FRONTAL WARMING AHEAD OF A BOUNDARY-LAYER BAROCLINIC ZONE COULD PRESENT A VERY WARM DAY ON MONDAY..WITH GUIDANCE CURRENTLY SUGGESTING AFTERNOON TEMPERATURE READINGS COULD SPIKE TO AROUND 100 DEGREES MONDAY AFTERNOON ACROSS OUR SOUTHERN ZONES...AND MORE INTO THE 90S FARTHER NORTH ACROSS THE AREA. ITS IMPORTANT TO NOTE THAT FRONTAL POSITION WILL PLAY A CRUCIAL ROLE IN TEMPERATURE READINGS ON MONDAY AND THIS WILL NEED TO BE CLOSELY MONITORED. THE INFILTRATION OF A COOLER BOUNDARY-LAYER AIR MASS POST-FROPA SHOULD THEN ALLOW FOR HIGHS IN THE 80S AND LOW 90S TO FINISH THE FORECAST PERIOD. FINALLY...RESULTANT HEAT INDEX READINGS MONDAY AFTERNOON ARE EXPECTED TO CLIMB INTO THE 100-105 RANGE ACROSS OUR KANSAS COUNTIES AND AS A RESULT...WILL CONTINUE MENTIONING THIS IN THE HWO. && .AVIATION...(FOR THE 06Z KGRI/KEAR TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1247 AM CDT SUN JUN 21 2015 OUR EAST NORTHEAST WIND WILL GRADUALLY BECOME MORE EASTERLY AS WE NEAR DAWN AND SHOULD BECOME MORE SOUTHEAST BY AFTERNOON. OVERALL THE WIND WILL BE LIGHT. LOW LEVEL WIND SHEAR MAY BE A PROBLEM LATE THIS EVENING ESPECIALLY FROM GRAND ISLAND EASTWARD AS THE LOW LEVEL JET INCREASES AND PUSHES BACK NORTH. THERE WILL BE A FAIR AMOUNT OF CLOUDS AROUND TODAY...BUT MOST GUIDANCE INDICATES CEILINGS WILL REMAIN VFR WITH CLOUD BASES AT OR ABOVE 4000 FT AGL. CAN NOT RULE OUT THE CHANCE OF A THUNDERSTORM PRIMARILY THIS MORNING...BUT TOO LOW OF A CHANCE TO INCLUDE IT IN THE TAF AT THIS POINT IN TIME. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...ADP LONG TERM...BRYANT AVIATION...WESELY
AREA FORECAST DISCUSSION
NWS RALEIGH NC
750 PM EDT MON JUN 22 2015 .SYNOPSIS...WEST TO NORTHWEST FLOW ALOFT WILL PREVAIL ACROSS THE REGION THROUGH MID-WEEK...ON THE NORTHEAST PERIPHERY OF AN UPPER LEVEL RIDGE CENTERED OVER THE LOWER MIDWEST AND LOWER MISSISSIPPI RIVER VALLEY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 PM MONDAY... CENTRAL NC REMAINS WITHIN A LOW-LEVEL MOISTURE MINIMUM THIS AFTERNOON...AS INDICATED BY 925-850 MB DEWPOINTS ~14C (PER SPC MESOANALYSIS)...AND AS ONE MIGHT INFER GIVEN WEAK/MODEST MID-LEVEL LAPSE RATES (NO SIGNIFICANT CAP) AND A LACK OF DIURNAL CU. AS A RESULT...INSTABILITY IS WEAKER AND CONVECTIVE INHIBITION IS GREATER THAN IN SURROUNDING AREAS...AND IT IS UNLIKELY THAT CONVECTION WILL DEVELOP WITHIN CENTRAL NC THE REMAINDER OF THE AFTERNOON. AN MCV WAS NOTED UPSTREAM OVER SOUTHEAST KY AT 21Z THIS AFTERNOON. THE LATEST RAP GUIDANCE INDICATES THIS FEATURE WILL TRACK SLOWLY ESE INTO SOUTHWEST VA BY ~00Z...SOUTHEASTWARD TO BOONE NC BY ~03Z... SSE/SOUTHWARD TO MORGANTON BY ~06Z AND CHARLOTTE BY ~09Z. IT IS POSSIBLE THAT DPVA ASSOCIATED WITH THIS FEATURE COULD PROVIDE SUFFICIENT FORCING TO AID CONVECTIVE DEVELOPMENT IN NORTHWEST NC AFTER 00Z...WITH PROPAGATION INTO THE TRIAD/NW PIEDMONT POSSIBLE BY ~03Z. IT SHOULD BE NOTED THAT NONE OF THE 12Z CAMS SUPPORT SUCH DEVELOPMENT...PROBABLY DUE TO UNFAVORABLE DIURNAL TIMING AND A DRIER/LESS SUPPORTIVE CONVECTIVE ENVIRONMENT...ASSUMING NO SIGNIFICANT LOW-LEVEL MOISTURE RECOVERY AFTER SUNSET. SHOULD CONVECTION DEVELOP OR PROPAGATE INTO THE TRIAD...DCAPE VALUES RANGING FROM 1000-1200 J/KG SUGGESTS ROBUST DOWNDRAFTS/COLD POOLS AND AN ATTENDANT POTENTIAL FOR DAMAGING WINDS...THOUGH DEEP LAYER SHEAR WILL BE MARGINALLY SUPPORTIVE OF MULTICELLULAR ORGANIZATION (AT BEST). -VINCENT && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 240 PM MONDAY... THE SUB-TROPICAL RIDGE WILL STRENGTHEN TO 325-326 DM OVER THE MID- SOUTH ON TUE...WITH AN ASSOCIATED UPTICK IN DOWNSTREAM LOW LEVEL THICKNESS VALUES AOA 1440 METERS OVER CENTRAL NC. HIGH TEMPERATURES ARE CONSEQUENTLY EXPECTED TO REACH THE UPPER 90S TO AROUND 100 DEGREES...LIKELY THE HOTTEST DAY OF THE WEEK. MODEL GUIDANCE SUGGESTS SFC DEWPOINTS WILL NOT MIX OUT AS MUCH AS PREVIOUS DAYS...AT LEAST NOT IN THE COASTAL PLAIN AND EASTERN SANDHILLS... WHERE AOA 70 DEGREES IS EXPECTED. AS SUCH...HEAT INDEX VALUES ARE FORECAST AROUND 105 DEGREES OR SO DURING THE AFTERNOON; AND ANOTHER HEAT ADVISORY HAS BEEN ISSUED FOR THE AREAS GENERALLY ALONG AND EAST OF INTERSTATE 95. SINCE THE PRIMARY FRONT...LIKELY A CONVECTIVELY-MODULATED ONE WILL REMAIN NORTH OF THE VA/NC BORDER THROUGH AT LEAST 12Z WED...FORCING AT THIS LATITUDE WILL NEED TO COME FROM OUTFLOW AND/OR AN MCV FROM UPSTREAM CONVECTION...NEITHER OF WHICH CAN BE FORECAST WITH MUCH CONFIDENCE AT THIS TIME RANGE. POP WILL CONSEQUENTLY BE KEPT IN THE SLIGHT TO LOW CHANCE RANGE...WITH THE RELATIVE BEST CHANCE ACROSS THE NORTHERN PIEDMONT LATE IN THE AFTERNOON AND EARLY EVENING GIVEN THE ORIENTATION OF THE RIDGE TO THE SOUTH AND ASSOCIATED TRACK OF MCS/S ACROSS THE TN VALLEY-CENTRAL APPALACHIANS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 315 PM MONDAY... WED/WED NIGHT: THE EXTENDED PERIOD WILL START WITH THE UPPER LEVEL HIGH CENTERED OVER THE MID-MS RIVER VALLEY AND THE UPPER LEVEL LOW OVER NE CANADA. CENTRAL NC WILL BE SANDWICHED IN BETWEEN THE TWO...WITH GENERALLY NW FLOW ALOFT. THE RIDGE WILL WEAKEN THROUGHOUT THE DAY...WITH INCREASING CHANCES FOR CONVECTION AS THE TROUGH PUSHES SOUTHWARD. MEANWHILE...A SURFACE BACKDOOR COLD FRONT WILL SLIDE SOUTH... STALLING OUT AROUND THE NC/VA BORDER BY LATE WED AFT/EVE. HIGHS WILL GENERALLY BE IN THE MID TO UPPER 90S NORTH TO SOUTH. OVERNIGHT LOWS IN THE LOW TO MID 70S. THROUGH THE WEEKEND: FOR THE REMAINDER OF THE EXTENDED...THE SURFACE FRONT WILL LIFT NORTHWARD AND PUSH SOUTHWARD AS A LOW SLOWLY DEVELOPS OVER THE UPPER MIDWEST. THE NEARLY ZONAL FLOW ALOFT WITH A S/W OR TWO WILL GRADUALLY BECOME A MORE AMPLIFIED TROUGH LATE IN THE WEEK... PROGRESSING INTO THE EASTERN U.S. LATE IN THE WEEK AND OVER THE WEEKEND. CONFIDENCE REGARDING CONVECTIVE CHANCES/TIMING/COVERAGE IS NOT TERRIBLY HIGH AT THIS TIME...HOWEVER THERE IS AT LEAST A CHANCE FOR SHOWERS/STORMS NEARLY EVERY DAY. HIGHS WILL GENERALLY BE IN THE MID 90S THROUGH FRIDAY...WITH THE INDICATION IN THE MODELS OF A COOLING TREND OVER THE WEEKEND. HIGHS SAT IN THE UPPER 80S TO LOW 90S. LOWS WILL FOLLOW A SIMILAR TREND... DECREASING INTO THE UPPER 60S TO MID 70S BY FRI NIGHT. SATURDAY NIGHT ONWARD: THE MODELS ARE CONSISTENTLY INDICATING COOL SURFACE HIGH PRESSURE RIDGING INTO CENTRAL NC FROM THE NORTHEAST BY SUNDAY...WHICH WOULD RESULT IN COOLER TEMPERATURES ACROSS THE REGION. ALTHOUGH NOT TERRIBLY CONFIDENT...HIGHS SUNDAY COULD BE IN THE MID TO UPPER 80S...WITH LOWS IN THE MID 60S TO LOW 70S. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 748 PM MONDAY... A FEW VERY ISOLATED SHOWERS/STORMS HAVE DEVELOPED IN ASSOCIATION WITH THE SEA BREEZE IN THE SOUTHERN COUNTIES... AND IN THE VICINITY OF KFAY. THIS ACTIVITY WILL BE SHORT LIVED. OTHERWISE VFR CONDITIONS ARE LIKELY THROUGH THE NEXT 24 HOURS AS HIGH PRESSURE REMAINS ACROSS THE AREA. WINDS WILL BECOME SOUTHWESTERLY BY TOMORROW AFTERNOON. SHOWERS AND STORMS WILL HAVE A RELATIVELY LOW PROBABILITY OF OCCURRENCE (~20 PERCENT) UNTIL A CONVECTIVE OUTFLOW-MODULATED FRONT SETTLES SOUTH INTO VA-NC ON WED AND SUPPORTS A BETTER CHANCE (30-50 PERCENT) AT THAT TIME. AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/22 100 1981 06/23 100 1986 06/24 99 2010 GSO RECORDS 06/22 100 1914 06/23 102 1914 06/24 103 1914 FAY RECORDS 06/22 101 1990 06/23 102 1981 06/24 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT TUESDAY FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...VINCENT NEAR TERM...VINCENT SHORT TERM...26 LONG TERM...RAH AVIATION...30/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
946 PM CDT MON JUN 22 2015 .UPDATE... ISSUED AT 940 PM CDT MON JUN 22 2015 NO CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO BLEND TO OBSERVED TRENDS THROUGH 02 UTC. THE 00-01 UTC HRRR ITERATIONS AND 00 UTC NAM ARE IN AGREEMENT ON ELEVATED CONVECTION DEVELOPING LATE TONIGHT TO REMAIN ACROSS NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA WITH INCREASING MOISTURE TRANSPORT IN ASSOCIATION WITH A MODEST LOW LEVEL JET. UPDATE ISSUED AT 627 PM CDT MON JUN 22 2015 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE WITH WEAK HIGH PRESSURE IN PLACE...AS A MOSTLY CLEAR OVERNIGHT IS EXPECTED FOR THE POTENTIAL STRONG NORTHERN LIGHTS SHOW. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 208 PM CDT MON JUN 22 2015 LATEST VISIBLE SATELLITE SHOWS A CUMULUS FIELD COVERING MOST OF WESTERN AND CENTRAL NORTH DAKOTA. VERTICAL EXTENT APPEARS LIMITED WITH BASES AROUND 4000FT EXTENDING UP TO AROUND 6000FT. SUBSIDENCE AND DRY AIR ALOFT WILL INHIBIT VERTICAL GROWTH AND HENCE LIMIT CHANCES FOR PRECIPITATION MINIMAL TO NIL. MAINTAINED A SLIGHT CHC POPS OVER THE HIGHER TERRAIN COVERING THE TURTLE MOUNTAINS SOUTH TO THE JAMES RIVER VALLEY. CLOUDS WILL WANE NEAR SUNSET WITH A MAINLY CLEAR SKY OVERNIGHT. LATEST WATER VAPOR IMAGERY SHOWS OUR NEXT SHORTWAVE TROUGH APPROACHING VANCOUVER ISLAND. THIS IS FORECAST TO MOVE EAST TUESDAY...REACHING NORTHWEST MONTANA/SOUTHERN ALBERTA BY 00Z WEDNESDAY. INSTABILITY WILL INCREASE TUESDAY AFTERNOON...MOSTLY ACROSS SOUTHWEST AS SOUTHERLY WINDS ADVECT HIGHER DEWPOINTS/MOISTURE. BY LATE AFTERNOON...CAPE INCREASES TO 1200 J/KG WITH 0-6KM SHEAR AT 50KT TO 60KT. HAVE CONTINUED WITH A SLIGHT CHANCE OF THUNDERSTORMS WEST AND NORTH TUESDAY AFTERNOON...WITH DRY CONDITIONS ELSEWHERE. AFTERNOON HIGHS WILL BE WARMER...BETWEEN 77F AND 82F. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 208 PM CDT MON JUN 22 2015 THE CURRENT SUITE OF ENSEMBLE AND DETERMINISTIC MODELS PROVIDE GENERAL AGREEMENT ON AN UPPER LEVEL SHORTWAVE TROUGH MOVING ACROSS THE STATE LATE TUESDAY THROUGH WEDNESDAY. THE WEATHER PREDICTION CENTER DAYS 1-3 HAS ROUGHLY HALF AN INCH OF QPF ACROSS THE STATE...AS A RESULT OF ASSOCIATED SHOWERS AND THUNDERSTORMS. THEREAFTER...QUASI ZONAL FLOW ALOFT IS EXPECTED TO TRANSITION INTO NORTHWEST FLOW BY THURSDAY...AS AN UPPER LEVEL RIDGE BUILDS OVER THE CONUS SOUTHWEST. NORTHWEST FLOW IS EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE LONG TERM WITH SEVERAL EMBEDDED MID-LEVEL SHORTWAVES PROJECTED ACROSS THE AREA. FREQUENT CHANCES FOR ISOLATED/SCATTERED THUNDERSTORMS ARE EXPECTED...THOUGH PREDICTABILITY IS LOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 940 PM CDT MON JUN 22 2015 VFR CONDITIONS EXPECTED THROUGH TUESDAY WITH WEAK HIGH PRESSURE IN PLACE. SCATTERED THUNDERSTORMS ARE POSSIBLE POST 00 UTC TUESDAY EVENING ACROSS WESTERN AND CENTRAL NORTH DAKOTA. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...KS LONG TERM...AC AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
211 PM CDT SUN JUN 21 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 211 PM CDT SUN JUN 21 2015 MAIN HIGHLIGHT IS THE SLIGHT RISK AND ENHANCED THUNDERSTORM RISK CATEGORY ACROSS WESTERN AND CENTRAL NORTH DAKOTA THROUGH SUNDAY NIGHT. LATEST HIGH RESOLUTION MODELS CONTINUE TO PORTRAY TWO ROUNDS OF SHOWERS/THUNDERSTORMS. LATEST REGIONAL/LOCAL RADAR SHOWS SCATTERED SHOWERS/THUNDERSTORMS IN NORTHWEST NORTH DAKOTA...AND AN INCREASE IN COVERAGE AND GROWTH EXPECTED IN THE NEXT FEW HOURS. HRRR REFLECTIVITY FORECAST SHOWS SUPERCELLS DEVELOPING REST OF THIS AFTERNOON AND MERGING INTO A COUPLE OF LINES/BOWING SEGMENTS 00Z THROUGH 05Z AS THEY CROSS INTO THE JAMES RIVER VALLEY. ANOTHER ROUND OF THUNDERSTORMS DEPICTED TO DEVELOP ALONG AND SOUTH OF INTERSTATE 94 BETWEEN 05Z AND 12Z MONDAY. MORE THAN SUFFICIENT CAPE/SHEAR FOR A PLETHORA OF SEVERE WEATHER THROUGH TONIGHT. CAPE NEARING 3000 J/KG ACROSS THE SOUTHWEST WITH 65KT OF 0-6KM SHEAR. THIS WAS WELL ADVERTISED IN PREVIOUS FORECASTS AND REMAINS WITH THIS DISCUSSION. LINGERING SHOWERS/THUNDERSTORMS MONDAY MORNING CENTRAL THEN TAPERING OFF BEFORE 18Z. DRY WEATHER MONDAY AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 211 PM CDT SUN JUN 21 2015 THE CURRENT ENSEMBLE AND DETERMINISTIC MODELS ARE PROJECTING QUASI ZONAL FLOW ALOFT GIVING WAY TO NORTHWEST FLOW...AS AN UPPER LEVEL TROUGH MOVES EASTWARD ACROSS THE STATE THROUGH WEDNESDAY...CREATING WIDESPREAD CHANCES FOR SHOWERS AND THUNDERSTORMS. THOUGH THE MODELS BEGIN TO WAVER LATER IN THE PERIOD...NORTHWEST FLOW ALOFT IS EXPECTED TO REMAIN IN PLACE OVER THE NORTHERN PLAINS THROUGH THE REST OF EXTENDED...AS A HIGH PRESSURE BUILDS OVER THE CONUS SOUTHWEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 211 PM CDT SUN JUN 21 2015 SCATTERED THUNDERSTORMS HAVE STARTED TO DEVELOP ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA. THESE STORMS WILL GRADUALLY PUSH SOUTH AND EAST THROUGH THE AFTERNOON AND NIGHT. SOME STORMS MAY BE SEVERE WITH LARGE HAIL AND HIGH WINDS THE MAIN THREATS. KISN...KDIK...AND KBIS WILL HAVE THE GREATEST CHANCE OF BEING IMPACTED BY SEVERE THUNDERSTORMS AND TSRA HAS BEEN PUT IN THE TAFS FOR THESE SITES. AT THIS TIME CONFIDENCE IS LOWER THAT A THUNDERSTORM WILL IMPACT KMOT AND KJMS...THUS HAVE WENT WITH VCTS FOR THESE SITES. THAT SAID MVFR AND IFR CONDITIONS WILL BE POSSIBLE AT ALL SITES IN THUNDERSTORMS. AFTER 10Z MONDAY SOME LOW CLOUDS AND FOG COULD DEVELOP ACROSS WESTERN AND CENTRAL NORTH DAKOTA BRINGING SOME MVFR TO IFR CONDITIONS...HOWEVER HAVE ELECTED TO KEEP CONDITIONS IN VFR FOR NOW AS CONFIDENCE IN COVERAGE IS LOW. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KS LONG TERM...AC AVIATION...MM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1227 PM CDT SUN JUN 21 2015 .UPDATE... ISSUED AT 1227 PM CDT SUN JUN 21 2015 LATEST REGIONAL/LOCAL RADAR SHOWS ISOLATED THUNDERSTORMS IN NORTHEAST MONTANA AND SOUTHERN SASKATCHEWAN. LINE OF SHOWERS ACROSS SOUTHWEST NORTH DAKOTA BUT MOST LIKELY NOT REACHING THE GROUND AS OF NOW. AN ISOLATED CELL/SHOWER WAS ALSO SEEN IN SOUTHWEST WARD COUNTY. SPC MESOANALYSIS SHOWS 60KT OF 0-6KM SHEAR IN SOUTHWEST NORTH DAKOTA WITH CAPE AT 2000 J/KG. AWAITING STEEPER MID LEVEL LAPSE RATES TO APPROACH FROM THE WEST WITH ADVANCING SHORTWAVES. LATEST HRRR CONTINUES TO SHOW STRONGEST REFLECTIVITYS SOUTHWEST THROUGH SOUTH CENTRAL MID TO LATE AFTERNOON...WITH SUPERCELLS INITIATING AND EMERGING INTO SEPARATE LINES AS THEY MOVE TOWARD THE JAMES RIVER VALLEY BETWEEN 03Z-05Z MONDAY. HRRR ALSO ADVERTISING ANOTHER ROUND OF THUNDERSTORMS DEVELOPING SOUTHWEST THROUGH SOUTH CENTRAL BETWEEN 03Z AND O6Z. THIS IS ASSOCIATED WITH A SHORTWAVE TROUGH/SURFACE LOW SHIFTING THROUGH THE NORTHERN ROCKIES AND ACROSS NORTH/SOUTH DAKOTA SUNDAY NIGHT. UPDATE ISSUED AT 942 AM CDT SUN JUN 21 2015 LATEST SPC CONVECTIVE OUTLOOK HAS EXPANDED THE ENHANCED AREA FARTHER WEST. LATEST HRRR MAX LAYER COLUMN REFLECTIVITY VIDEO LOOKS VERY SIMILAR TO THE EVENT FROM THIS PAST FRIDAY. WATER VAPOR IMAGERY SHOWS A SHORTWAVE SLIDING OVER FAR SOUTHEAST BRITISH COLUMBIA AND WESTERN ALBERTA ALONG WITH A 100KT JET STREAK. ADDITIONAL SHORTWAVES WERE NOTED EXTENDING FROM THE IDAHO PANHANDLE ACROSS NORTHERN MONTANA. AS MENTIONED IN THE EARLIER DISCUSSION...AND LATEST HRRR...EXPECTATIONS FOR SUPERCELL DEVELOPMENT OCCURS BETWEEN 20Z AND 21Z WEST/NORTHWEST THEN MERGES INTO A MCS/BOWING LINE SEGMENT BETWEEN 00Z AND 06Z AS IT WORKS ACROSS WESTERN AND CENTRAL NORTH DAKOTA. LATEST NSHARP SOUNDINGS SHOWS CIN ERODING COMPLETELY BY 20Z AT KISN/KDIK...AND BY 22Z AT KMOT/KBIS. HAVE COORDINATED WITH SPC AND WILL PERFORM AN 18Z UPPER AIR LAUNCH. RAPID SCAN SATELLITE OPERATIONS IN EFFECT FROM 17Z SUNDAY THROUGH 12Z MONDAY. MINIMAL CHANGES TO CURRENT FORECAST AS THE OVERALL THEME IS WELL CAPTURED AND REMAINS ON TRACK. UPDATE ISSUED AT 624 AM CDT SUN JUN 21 2015 MAINLY CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS MORNING. LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL CIRCULATIONS OVER SOUTHERN BRITISH COLUMBIA AND OFF THE OREGON COAST. SHORTWAVES TRAVELING AROUND THE BASES OF EACH OF THESE LOWS WILL TRACK ACROSS THE ROCKIES TODAY...INDUCING SURFACE LOW PRESSURE OVER THE NORTHERN AND CENTRAL HIGH PLAINS. THIS WILL SET THE STAGE FOR THUNDERSTORM DEVELOPMENT ACROSS THE NORTHERN PLAINS AND SOUTHERN CANADIAN PRAIRIE PROVINCES THIS AFTERNOON AND CONTINUING THROUGH TONIGHT. KEEP ALERT TO THE LATEST WEATHER CONDITIONS IF YOU ARE ENJOYING OUTDOOR ACTIVITIES TODAY. NO SIGNIFICANT CHANGES TO THE EARLY MORNING UPDATE OTHER THAN LOWERING SKY COVER THROUGH THE MORNING HOURS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 250 AM CDT SUN JUN 21 2015 THE MAIN FOCUS FOR THE SHORT TERM IS THE POTENTIAL FOR SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING. IN THE LATEST SEVERE THUNDERSTORM OUTLOOK...THE STORM PREDICTION CENTER HAS EXPANDED THE SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS THE ENTIRE STATE AND INCLUDED PORTIONS OF SOUTHERN NORTH DAKOTA IN AN ENHANCED RISK. GUIDANCE CONTINUES TO SUGGEST THUNDERSTORM DEVELOPMENT BY AFTERNOON ACROSS WESTERN NORTH DAKOTA. AN UPPER LEVEL SHORTWAVE ACROSS THE MOUNTAIN WEST WILL APPROACH THE WESTERN DAKOTAS BY THE AFTERNOON HOURS. AHEAD OF THIS WAVE...A SURFACE LOW WILL DEVELOP ACROSS EASTERN MONTANA. THESE WILL PROVIDE THE FOCUS AND LIFT FOR DEVELOPMENT LATER THIS AFTERNOON. THE RAP/NAM/GFS/WRF ALL INDICATE PLENTY OF INSTABILITY (2000 J/KG CAPE) AND SHEAR (50+ KNOTS) FOR ORGANIZED SUPERCELLULAR DEVELOPMENT. ADDITIONALLY...FORECAST SOUNDINGS SHOW A SICKLE OR SHARPLY VEERING WIND PROFILE WITH HEIGHT. EVEN THOUGH LCL LEVELS VARY WIDELY FROM ONE MODEL TO ANOTHER...GENERALLY THIS TYPE OF WIND PROFILE WOULD SUPPORT A TORNADO THREAT...AT LEAST INITIALLY WITH SUPERCELL STRUCTURES. THEREFORE...ALL TYPES OF SEVERE THUNDERSTORM HAZARDS ARE POSSIBLE TODAY (HAIL...DAMAGING WIND...VERY HEAVY RAIN AND A FEW TORNADOES). A VERY SIMILAR SET UP TO FRIDAY IS POSSIBLE...WITH ISOLATED CELLS CONGEALING INTO A BOWING MCS BY THE EVENING HOURS. THE WRF ACTUALLY HAS TWO SEPARATE COMPLEXES MOVING THROUGH SOUTHERN NORTH DAKOTA...ONE EXITING THE AREA BY AROUND 7 PM AND ANOTHER MOVING THROUGH CLOSER TO MIDNIGHT. THE BIGGEST THREAT WITH THESE COMPLEXES WOULD BE DAMAGING WIND. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 250 AM CDT SUN JUN 21 2015 ALTHOUGH THERE MAY BE SOME LINGERING CONVECTION MONDAY MORNING IN THE WAKE OF THE SHORT TERM SYSTEM...MONDAY IS EXPECTED TO BEGIN A SHORT DRY SPELL AS HIGH PRESSURE TRAVERSES THE NORTHERN PLAINS. SURFACE HIGH PRESSURE THEN REMAINS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST MONDAY NIGHT INTO TUESDAY. THE UPPER LEVEL JET REMAINS DIRECTLY OVERHEAD DURING THIS PERIOD SO AN ISOLATED SHOWER OR THUNDERSTORM CANNOT BE COMPLETELY RULED OUT...BUT FOR NOW WE HAVE A DRY FORECAST MONDAY NIGHT AND JUST A SLIGHT CHANCE OF A THUNDERSTORM FAR SOUTHWEST AND NORTHWEST ON TUESDAY. A SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN ROCKIES TUESDAY AND INTO THE NORTHERN PLAINS TUESDAY NIGHT...BRINGING A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS TUESDAY NIGHT THROUGH WEDNESDAY. A BRIEF BREAK IS POSSIBLE THURSDAY AS GFS/ECMWF INDICATE SHORTWAVE RIDGING OVER THE FORECAST AREA...AHEAD OF ANOTHER SHORTWAVE TROUGH THAT BRINGS AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY. MODEL DIFFERENCES BEGIN TO INCREASE BY THIS TIME SO CERTAINTY BEGINS TO WANE AS WE MOVE LATE INTO THE WORK WEEK AND INTO NEXT WEEKEND. BOTH THE ECMWF/GFS MODELS ARE INDICATING A BUILDING WESTERN RIDGE BUT THE GFS IS MUCH SLOWER WITH AN UNSETTLED BEGINNING TO THE WEEKEND. THE ECMWF SOLUTION WOULD BRING A DRIER WEEKEND...BUT NOT COMPLETELY WITHOUT A MENTION OF THUNDERSTORMS AS A NORTHWEST FLOW DEVELOPS...AND SHORTWAVES ARE ALWAYS A CONCERN IN THIS FLOW. HOWEVER...AREAL COVERAGE WOULD BE MUCH LESS THAN THE GFS SOLUTION...ESPECIALLY ON SATURDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1227 PM CDT SUN JUN 21 2015 SCATTERED THUNDERSTORMS HAVE STARTED TO DEVELOP ACROSS EASTERN MONTANA AND WESTERN NORTH DAKOTA. THESE STORMS WILL GRADUALLY PUSH SOUTH AND EAST THROUGH THE AFTERNOON AND NIGHT. SOME STORMS MAY BE SEVERE WITH LARGE HAIL AND HIGH WINDS THE MAIN THREATS. KISN...KDIK...AND KBIS WILL HAVE THE GREATEST CHANCE OF BEING IMPACTED BY SEVERE THUNDERSTORMS AND TSRA HAS BEEN PUT IN THE TAFS FOR THESE SITES. AT THIS TIME CONFIDENCE IS LOWER THAT A THUNDERSTORM WILL IMPACT KMOT AND KJMS...THUS HAVE WENT WITH VCTS FOR THESE SITES. THAT SAID MVFR AND IFR CONDITIONS WILL BE POSSIBLE AT ALL SITES IN THUNDERSTORMS. AFTER 10Z MONDAY SOME LOW CLOUDS AND FOG COULD DEVELOP ACROSS WESTERN AND CENTRAL NORTH DAKOTA BRINGING SOME MVFR TO IFR CONDITIONS...HOWEVER HAVE ELECTED TO KEEP CONDITIONS IN VFR FOR NOW AS CONFIDENCE IN COVERAGE IS LOW. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...AJ LONG TERM...TWH AVIATION...MM
AREA FORECAST DISCUSSION
NWS BISMARCK ND
942 AM CDT SUN JUN 21 2015 .UPDATE... ISSUED AT 942 AM CDT SUN JUN 21 2015 LATEST SPC CONVECTIVE OUTLOOK HAS EXPANDED THE ENHANCED AREA FARTHER WEST. LATEST HRRR MAX LAYER COLUMN REFLECTIVITY VIDEO LOOKS VERY SIMILAR TO THE EVENT FROM THIS PAST FRIDAY. WATER VAPOR IMAGERY SHOWS A SHORTWAVE SLIDING OVER FAR SOUTHEAST BRITISH COLUMBIA AND WESTERN ALBERTA ALONG WITH A 100KT JET STREAK. ADDITIONAL SHORTWAVES WERE NOTED EXTENDING FROM THE IDAHO PANHANDLE ACROSS NORTHERN MONTANA. AS MENTIONED IN THE EARLIER DISCUSSION...AND LATEST HRRR...EXPECTATIONS FOR SUPERCELL DEVELOPMENT OCCURS BETWEEN 20Z AND 21Z WEST/NORTHWEST THEN MERGES INTO A MCS/BOWING LINE SEGMENT BETWEEN 00Z AND 06Z AS IT WORKS ACROSS WESTERN AND CENTRAL NORTH DAKOTA. LATEST NSHARP SOUNDINGS SHOWS CIN ERODING COMPLETELY BY 20Z AT KISN/KDIK...AND BY 22Z AT KMOT/KBIS. HAVE COORDINATED WITH SPC AND WILL PERFORM AN 18Z UPPER AIR LAUNCH. RAPID SCAN SATELLITE OPERATIONS IN EFFECT FROM 17Z SUNDAY THROUGH 12Z MONDAY. MINIMAL CHANGES TO CURRENT FORECAST AS THE OVERALL THEME IS WELL CAPTURED AND REMAINS ON TRACK. UPDATE ISSUED AT 624 AM CDT SUN JUN 21 2015 MAINLY CLEAR SKIES ACROSS WESTERN AND CENTRAL NORTH DAKOTA EARLY THIS MORNING. LATEST SATELLITE IMAGERY SHOWS UPPER LEVEL CIRCULATIONS OVER SOUTHERN BRITISH COLUMBIA AND OFF THE OREGON COAST. SHORTWAVES TRAVELING AROUND THE BASES OF EACH OF THESE LOWS WILL TRACK ACROSS THE ROCKIES TODAY...INDUCING SURFACE LOW PRESSURE OVER THE NORTHERN AND CENTRAL HIGH PLAINS. THIS WILL SET THE STAGE FOR THUNDERSTORM DEVELOPMENT ACROSS THE NORTHERN PLAINS AND SOUTHERN CANADIAN PRAIRIE PROVINCES THIS AFTERNOON AND CONTINUING THROUGH TONIGHT. KEEP ALERT TO THE LATEST WEATHER CONDITIONS IF YOU ARE ENJOYING OUTDOOR ACTIVITIES TODAY. NO SIGNIFICANT CHANGES TO THE EARLY MORNING UPDATE OTHER THAN LOWERING SKY COVER THROUGH THE MORNING HOURS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 250 AM CDT SUN JUN 21 2015 THE MAIN FOCUS FOR THE SHORT TERM IS THE POTENTIAL FOR SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING. IN THE LATEST SEVERE THUNDERSTORM OUTLOOK...THE STORM PREDICTION CENTER HAS EXPANDED THE SLIGHT RISK FOR SEVERE THUNDERSTORMS ACROSS THE ENTIRE STATE AND INCLUDED PORTIONS OF SOUTHERN NORTH DAKOTA IN AN ENHANCED RISK. GUIDANCE CONTINUES TO SUGGEST THUNDERSTORM DEVELOPMENT BY AFTERNOON ACROSS WESTERN NORTH DAKOTA. AN UPPER LEVEL SHORTWAVE ACROSS THE MOUNTAIN WEST WILL APPROACH THE WESTERN DAKOTAS BY THE AFTERNOON HOURS. AHEAD OF THIS WAVE...A SURFACE LOW WILL DEVELOP ACROSS EASTERN MONTANA. THESE WILL PROVIDE THE FOCUS AND LIFT FOR DEVELOPMENT LATER THIS AFTERNOON. THE RAP/NAM/GFS/WRF ALL INDICATE PLENTY OF INSTABILITY (2000 J/KG CAPE) AND SHEAR (50+ KNOTS) FOR ORGANIZED SUPERCELLULAR DEVELOPMENT. ADDITIONALLY...FORECAST SOUNDINGS SHOW A SICKLE OR SHARPLY VEERING WIND PROFILE WITH HEIGHT. EVEN THOUGH LCL LEVELS VARY WIDELY FROM ONE MODEL TO ANOTHER...GENERALLY THIS TYPE OF WIND PROFILE WOULD SUPPORT A TORNADO THREAT...AT LEAST INITIALLY WITH SUPERCELL STRUCTURES. THEREFORE...ALL TYPES OF SEVERE THUNDERSTORM HAZARDS ARE POSSIBLE TODAY (HAIL...DAMAGING WIND...VERY HEAVY RAIN AND A FEW TORNADOES). A VERY SIMILAR SET UP TO FRIDAY IS POSSIBLE...WITH ISOLATED CELLS CONGEALING INTO A BOWING MCS BY THE EVENING HOURS. THE WRF ACTUALLY HAS TWO SEPARATE COMPLEXES MOVING THROUGH SOUTHERN NORTH DAKOTA...ONE EXITING THE AREA BY AROUND 7 PM AND ANOTHER MOVING THROUGH CLOSER TO MIDNIGHT. THE BIGGEST THREAT WITH THESE COMPLEXES WOULD BE DAMAGING WIND. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 250 AM CDT SUN JUN 21 2015 ALTHOUGH THERE MAY BE SOME LINGERING CONVECTION MONDAY MORNING IN THE WAKE OF THE SHORT TERM SYSTEM...MONDAY IS EXPECTED TO BEGIN A SHORT DRY SPELL AS HIGH PRESSURE TRAVERSES THE NORTHERN PLAINS. SURFACE HIGH PRESSURE THEN REMAINS FROM THE NORTHERN PLAINS INTO THE UPPER MIDWEST MONDAY NIGHT INTO TUESDAY. THE UPPER LEVEL JET REMAINS DIRECTLY OVERHEAD DURING THIS PERIOD SO AN ISOLATED SHOWER OR THUNDERSTORM CANNOT BE COMPLETELY RULED OUT...BUT FOR NOW WE HAVE A DRY FORECAST MONDAY NIGHT AND JUST A SLIGHT CHANCE OF A THUNDERSTORM FAR SOUTHWEST AND NORTHWEST ON TUESDAY. A SHORTWAVE TROUGH MOVES ACROSS THE NORTHERN ROCKIES TUESDAY AND INTO THE NORTHERN PLAINS TUESDAY NIGHT...BRINGING A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS TUESDAY NIGHT THROUGH WEDNESDAY. A BRIEF BREAK IS POSSIBLE THURSDAY AS GFS/ECMWF INDICATE SHORTWAVE RIDGING OVER THE FORECAST AREA...AHEAD OF ANOTHER SHORTWAVE TROUGH THAT BRINGS AN INCREASING CHANCE OF SHOWERS AND THUNDERSTORMS THURSDAY NIGHT INTO FRIDAY. MODEL DIFFERENCES BEGIN TO INCREASE BY THIS TIME SO CERTAINTY BEGINS TO WANE AS WE MOVE LATE INTO THE WORK WEEK AND INTO NEXT WEEKEND. BOTH THE ECMWF/GFS MODELS ARE INDICATING A BUILDING WESTERN RIDGE BUT THE GFS IS MUCH SLOWER WITH AN UNSETTLED BEGINNING TO THE WEEKEND. THE ECMWF SOLUTION WOULD BRING A DRIER WEEKEND...BUT NOT COMPLETELY WITHOUT A MENTION OF THUNDERSTORMS AS A NORTHWEST FLOW DEVELOPS...AND SHORTWAVES ARE ALWAYS A CONCERN IN THIS FLOW. HOWEVER...AREAL COVERAGE WOULD BE MUCH LESS THAN THE GFS SOLUTION...ESPECIALLY ON SATURDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 624 AM CDT SUN JUN 21 2015 VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THIS MORNING AND INTO THIS AFTERNOON. SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS WESTERN NORTH DAKOTA DURING THE AFTERNOON. SOME THUNDERSTORMS COULD BE SEVERE...WITH LARGE HAIL AND DAMAGING WIND. THE THREAT FOR THUNDERSTORMS WILL SHIFT EASTWARD DURING THE EVENING HOURS. MVFR-IFR CONDITIONS ARE EXPECTED WITH ANY THUNDERSTORMS THAT DEVELOP. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KS SHORT TERM...AJ LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
629 PM EDT SUN JUN 21 2015 .SYNOPSIS... A MEANDERING EAST TO WEST FRONT WILL MEANDER/OSCILLATE NORTH AND SOUTH. ROUNDS OF CONVECTION. TEMPERATURES MAY TREND LOWER TOWARD THE WEEKEND. && .NEAR TERM /THROUGH MONDAY/... 630 PM UPDATE...MADE A FEW TWEAKS TO THE FORECAST FOR THIS AFTERNOON/EVENING. REDUCED POPS ACROSS THE NORTH A BIT FROM PREVIOUS FORECAST...AND LESS ACTIVITY THERE DUE TO DRIER ATMOSPHERE. DID ELECT TO ADD IN A SLIGHT CHANCE TO CHANCE ON MONDAY...WITH ACTIVITY STARTING IN THE MORNING...AS NEAR TERM MODELS INDICATING POSSIBILITY FOR ACTIVITY IN CENTRAL INDIANA TO MAKE ITS WAY/SURVIVE INTO OUR CWA BY MORNING. CONTINUED SLIGHT TO CHANCE TOMORROW AS FRONTAL BOUNDARY IS PROGGED GRADUALLY LIFT BACK NORTH ACROSS THE CWA. PREVIOUS DISCUSSION FOLLOWS... FAIRLY UNIFORM CU FIELD OVER THE CWA THIS AFTERNOON WITH MOIST BL IN PLACE. REMAINING DEBRIS CLOUDS HAVE SHIFTED INTO SOUTHERN COAL FIELDS AND CENTRAL VA. OTHERWISE...SWIFT MID LEVEL FLOW LEADING TO A FEW GUSTY WIND REPORTS HERE AND THERE. LATEST RAP AND HRRR MODELS BOTH SEEM TO ADVERTISE THAT THE BEST FOCUS FOR CONVECTIVE INITIATION THIS AFTERNOON WILL BE ACROSS THE SOUTHERN COAL FIELDS OF WV. MAIN AXIS OF INSTABILITY AND MOISTURE STRETCHES ACROSS CENTRAL KY AND INTO SRN WV WHICH CORRELATES WELL WITH HIRES MODELS...AND EXPECTED CONVECTIVE DEVELOPMENT. 88D RETURNS FROM 1820Z ARE JUST STARTING TO SHOW SIGNS OF DEVELOPMENT IN KY...AND VA WV BORDERS. FOR TEMPS...MADE MINOR TWEAKS TO TEMPS MAX TEMPS...LEANING A LITTLE CLOSER TO MAV NUMBERS OVER THE MET. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... FIGURING THE BOUNDARY LAYER WINDS WILL INCREASE MONDAY NIGHT...WILL GO WITH A WARMER NIGHT IN THE OHIO VALLEY COUNTIES. 925 MB WINDS WINDS ON NAM ABOUT 30 TO 35 KNOTS VCNTY PKB. AS IS USUALLY THE CASE IN THE SUMMER...TIMING THE FRONT SOUTH...AND HOW FAR SOUTH IT MAKES IT BY WEDNESDAY MORNING IS DIFFICULT. WILL NOT GO WITH THE FASTER 12Z GFS AT THIS TIME...BUT STILL PLAY UP FAVORABLE TIMING FOR AFTERNOON CONVECTION. FIGURING 2500 CAPE COULD DEVELOP...WITH SOME SEVERE CELLS POSSIBLE. HAVE POPS LOWERING NORTH TO SOUTH...OVERNIGHT TUESDAY NIGHT...AS FRONT SINKS SOUTH. NOT CONFIDENT AT THIS TIME...THAT THE FRONTAL ZONE WILL CLEAR SOUTHERN COUNTIES...SO LEFT SOME 20/30 POPS EVEN DURING THE PREDAWN/DAWN TIME FRAME FOR WEDNESDAY. WILL TRY TO KEEP NORTHERN COUNTIES DRY A BIT LONGER ON WEDNESDAY. HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... WE CONTINUE TO RIDE THE RAIN TRAIN WITH THE FRONTAL ZONE OSCILLATING IN OUR VICINITY. WITH THE 500 MB RIDGE OUT WEST...HAVE AFTERNOON TEMPERATURES TRENDING TOWARD BELOW NORMAL BY THE WEEKEND. REMAIN HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY. SO WILL INCREASE POPS CENTRAL AND NORTHERN COUNTIES DURING THE DAY ON THURSDAY. MOST SIGNIFICANT WAVE ACTION/500 MB TROF/ APPEARS TO BE SATURDAY INTO SATURDAY...SO DESPITE BEING DAY 6/7 WILL INCLUDE SOME LIKELY POPS. THOSE MAXIMUM TEMPERATURES SHOULD BE HELD DOWN TOO. USE WPC MEDIUM RANGE GUIDANCE FOR MAJORITY OF TIME FRAME. && .AVIATION /00Z MONDAY THROUGH FRIDAY/... LOW LEVEL BOUNDARY LEVELS QUITE MOIST THIS MORNING WITH 70 PLUS DP VALUES STRETCHING UP ALONG THE OHIO RIVER. WE HAVE BEEN A LITTLE SLOW TO SEE LIFTING OF STRATOCU DECK BY A FEW MORE HOURS. DEBRIS CLOUD FROM PREVIOUS NIGHTS MCS HAS MORE OR LESS WASHED OUT ACROSS THE SOUTHERN COALFIELDS AND CENTRAL VIRGINIA....WHILE BL STRATOCU REMAIN NORTH AND WEST. PUSHED FOCUS FOR CONVECTIVE DEVELOPMENT FURTHER SOUTH AS WEAK DISTURBANCES MOVE ACROSS...AND BEST INSTABILITY RESIDES. SFC FLOW A BIT GUSTY DURING THE AFTERNOON HOURS. KEPT GENERALLY MVFR CONDITIONS FOR OVERNIGHT HOURS...THE EXCEPTION BEING KEKN WHERE SOME BRIEF IFR CAN BE EXPECTED FOR THE EARLY MORNING. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY... FORECAST CONFIDENCE: LOW TO MEDIUM. ALTERNATE SCENARIOS: TIMING...ANY THUNDERSTORM THAT DIRECTLY HITS AN AIRPORT THIS AFTERNOON COULD BRING IFR CONDITIONS AND STRONG WIND GUSTS. .AFTER 18Z SUNDAY... IFR POSSIBLE TUESDAY IN SHOWERS AND THUNDERSTORMS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/ARJ NEAR TERM...SL/KMC SHORT TERM...JSH/KTB LONG TERM...KTB AVIATION...KMC
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
445 PM EDT SUN JUN 21 2015 .SYNOPSIS... A MEANDERING EAST TO WEST FRONT WILL MEANDER/OSCILLATE NORTH AND SOUTH. ROUNDS OF CONVECTION. TEMPERATURES MAY TREND LOWER TOWARD THE WEEKEND. && .NEAR TERM /THROUGH MONDAY/... FAIRLY UNIFORM CU FIELD OVER THE CWA THIS AFTERNOON WITH MOIST BL IN PLACE. REMAINING DEBRIS CLOUDS HAVE SHIFTED INTO SOUTHERN COAL FIELDS AND CENTRAL VA. OTHERWISE...SWIFT MID LEVEL FLOW LEADING TO A FEW GUSTY WIND REPORTS HERE AND THERE. LATEST RAP AND HRRR MODELS BOTH SEEM TO ADVERTISE THAT THE BEST FOCUS FOR CONVECTIVE INITIATION THIS AFTERNOON WILL BE ACROSS THE SOUTHERN COAL FIELDS OF WV. MAIN AXIS OF INSTABILITY AND MOISTURE STRETCHES ACROSS CENTRAL KY AND INTO SRN WV WHICH CORRELATES WELL WITH HIRES MODELS...AND EXPECTED CONVECTIVE DEVELOPMENT. 88D RETURNS FROM 1820Z ARE JUST STARTING TO SHOW SIGNS OF DEVELOPMENT IN KY...AND VA WV BORDERS. FOR TEMPS...MADE MINOR TWEAKS TO TEMPS MAX TEMPS...LEANING A LITTLE CLOSER TO MAV NUMBERS OVER THE MET. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... FIGURING THE BOUNDARY LAYER WINDS WILL INCREASE MONDAY NIGHT...WILL GO WITH A WARMER NIGHT IN THE OHIO VALLEY COUNTIES. 925 MB WINDS WINDS ON NAM ABOUT 30 TO 35 KNOTS VCNTY PKB. AS IS USUALLY THE CASE IN THE SUMMER...TIMING THE FRONT SOUTH...AND HOW FAR SOUTH IT MAKES IT BY WEDNESDAY MORNING IS DIFFICULT. WILL NOT GO WITH THE FASTER 12Z GFS AT THIS TIME...BUT STILL PLAY UP FAVORABLE TIMING FOR AFTERNOON CONVECTION. FIGURING 2500 CAPE COULD DEVELOP...WITH SOME SEVERE CELLS POSSIBLE. HAVE POPS LOWERING NORTH TO SOUTH...OVERNIGHT TUESDAY NIGHT...AS FRONT SINKS SOUTH. NOT CONFIDENT AT THIS TIME...THAT THE FRONTAL ZONE WILL CLEAR SOUTHERN COUNTIES...SO LEFT SOME 20/30 POPS EVEN DURING THE PREDAWN/DAWN TIME FRAME FOR WEDNESDAY. WILL TRY TO KEEP NORTHERN COUNTIES DRY A BIT LONGER ON WEDNESDAY. HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... WE CONTINUE TO RIDE THE RAIN TRAIN WITH THE FRONTAL ZONE OSCILLATING IN OUR VICINITY. WITH THE 500 MB RIDGE OUT WEST...HAVE AFTERNOON TEMPERATURES TRENDING TOWARD BELOW NORMAL BY THE WEEKEND. REMAIN HAVE THE FRONT LIFTING BACK NORTH WEDNESDAY NIGHT INTO THURSDAY. SO WILL INCREASE POPS CENTRAL AND NORTHERN COUNTIES DURING THE DAY ON THURSDAY. MOST SIGNIFICANT WAVE ACTION/500 MB TROF/ APPEARS TO BE SATURDAY INTO SATURDAY...SO DESPITE BEING DAY 6/7 WILL INCLUDE SOME LIKELY POPS. THOSE MAXIMUM TEMPERATURES SHOULD BE HELD DOWN TOO. USE WPC MEDIUM RANGE GUIDANCE FOR MAJORITY OF TIME FRAME. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/... LOW LEVEL BOUNDARY LEVELS QUITE MOIST THIS MORNING WITH 70 PLUS DP VALUES STRETCHING UP ALONG THE OHIO RIVER. WE HAVE BEEN A LITTLE SLOW TO SEE LIFTING OF STRATCU DECK BY A FEW MORE HOURS. DEBRIS CLOUD FROM PREVIOUS NIGHTS MCS HAS MORE OR LESS WASHED OUT ACROSS THE SOUTHERN COALFIELDS AND CENTRAL VIRGINIA....WHILE BL STRATCU REMAIN NORTH AND WEST. PUSHED FOCUS FOR CONVECTIVE DEVELOPMENT FURTHER SOUTH AS WEAK DISTURBANCES MOVE ACROSS...AND BEST INSTABILITY RESIDES. SFC FLOW A BIT GUSTY DURING THE AFTERNOON HOURS. KEPT GENERALLY MVFR CONDITIONS FOR OVERNIGHT HOURS...THE EXCEPTION BEING KEKN WHERE SOME BRIEF IFR CAN BE EXPECTED FOR THE EARLY MORNING. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY... FORECAST CONFIDENCE: LOW TO MEDIUM. ALTERNATE SCENARIOS: TIMING...ANY THUNDERSTORM THAT DIRECTLY HITS AN AIRPORT THIS AFTERNOON COULD BRING IFR CONDITIONS AND STRONG WIND GUSTS. .AFTER 18Z SUNDAY... IFR POSSIBLE TUESDAY IN SHOWERS AND THUNDERSTORMS. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/ARJ NEAR TERM...KMC SHORT TERM...JSH/KTB LONG TERM...KTB AVIATION...KMC
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
441 PM EDT SUN JUN 21 2015 .SYNOPSIS... A FEW SHOWERS AND THUNDERSTORMS MAY FORM TONIGHT ALONG A QUASI STATIONARY FRONTAL BOUNDARY LOCATED NEAR THE OHIO RIVER. THE BOUNDARY WILL LIFT NORTHEAST AS A WARM FRONT ON MONDAY... PROVIDING A CHANCE FOR MORE SHOWERS AND THUNDERSTORMS. A COLD FRONT WILL BRING A BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS ON TUESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... A WEAK AND ILL DEFINED FRONTAL BOUNDARY IS PUSHING THROUGH SOUTHERN PORTIONS OF THE FORECAST AREA. WITH STRONG TO SEVERE THUNDERSTORMS CONFINED TO SOUTHERN KENTUCKY AND WEST VIRGINIA IN AN AREA OF HIGHER DEW POINTS AND INSTABILITY...NO CONVECTION HAS BEEN ASSOCIATED WITH THE FRONT TODAY OVER ILN. EXPECT THE LACK OF CONVECTION TO CONTINUE EARLY THIS EVENING...THOUGH THERE WILL BE A SLIGHT CHANCE OF A SHOWER. LATER THIS EVENING THROUGH TONIGHT ...THUNDERSTORMS MAY AFFECT SOUTHERN LOCATIONS AIDED BY FRONTOGENESIS ALONG THE SLOW MOVING BOUNDARY. SOME OF THIS CONVECTION IS ALREADY EVIDENT OVER SOUTHERN INDIANA AND IT WILL BEAR WATCHING AS IT MOVES CLOSER AS SUGGESTED BY RAP MODEL. LOWS RANGING FROM THE MID 60S NORTH TO AROUND 70 SOUTH WILL BE A BIT COOLER THAN IN RECENT NIGHTS. && .SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/... FOR MONDAY...A WARM FRONT EXTENDING FROM WESTERN GREAT LAKES LOW PRESSURE WILL BE LIFTING NORTHEAST ACROSS THE AREA. THOUGH THERE WILL BE AMPLE INSTABILITY WITH MODELS INDICATING UP TO AROUND 3500 J/KG CAPE...THE EARLY AFTERNOON TIMING OF THE WARM FRONT MOVING NORTHEAST MAY MEAN THAT MOISTURE TRANSPORT AND LIFT MAY NOT BE WELL IN PHASE WITH PEAK AFTERNOON INSTABILITY. KEPT A CHANCE OF SHOWERS AND THUNDERSTORMS IN A NW-SE ORIENTED BAND LIFTING NORTHEAST ACROSS THE AREA ALIGNED ALONG THE WARM FRONT. THOUGH WIDESPREAD SEVERE THUNDERSTORMS ARE NOT EXPECTED DUE TO A LACK OF STRONG FORCING AND WIND FIELDS...A FEW CELLS MAY BECOME STRONG TO SEVERE IN THE RATHER HIGH CAPE ENVIRONMENT...WITH DOWNBURSTS POSSIBLY AIDED BY FAVORABLE DELTA THETA E. FOR MONDAY NIGHT...A LULL IN CONVECTION EARLY MAY BE FOLLOWED BY MORE SHOWERS AND THUNDERSTORMS THAT COULD DEVELOP IN NORTHERN LOCATIONS AHEAD OF THE NEXT COLD FRONT APPROACHING FROM THE NORTHWEST. HIGH TEMPERATURES ON MONDAY ARE FORECAST TO RANGE FROM THE MID 80S NORTHEAST TO 90 SOUTHWEST. LOWS MONDAY NIGHT ARE LIKELY TO STAY UP IN THE LOWER 70S DUE TO WARM ADVECTION AND INCREASING MOISTURE AHEAD OF THE COLD FRONT. && .LONG TERM /TUESDAY THROUGH SUNDAY/... MID LEVEL RIDGE ACROSS THE SOUTHERN US WITH ACTIVE BAND OF WESTERLIES ACROSS THE NORTHERN TIER OF STATES AND GREAT LAKES TO DOMINATE THE WEATHER THRU THE END OF THE WEEK. A SERIES OF PERTURBATIONS TO COME THRU THE WESTERLY FLOW WITH E-W SURFACE FRONTAL BOUNDARY OSCILLATING NORTH/SOUTH ACRS THE REGION. MODEL SOLNS GENERALLY CONSISTENT WITH SFC WAVE TRACKING THRU THE NORTHERN GREAT LAKES AND ASSOCIATED SFC FRONT DROPPING INTO OHIO VALLEY TUESDAY AND LAYING OUT E-W PARALLEL TO UPPER LEVEL FLOW STALLING OUT SOUTH OF THE OHIO RIVER TUE NIGHT/WED. THIS FRONT WILL BE THE FOCUS FOR CONVECTION. THIS FRONT LOOKS TO FOCUS BEST CHANCE OF CONVECTION ACRS SRN FA TUESDAY AFTN INTO EARLY WEDNESDAY AND THEN LIFT BACK NORTH LATER WED INTO THURSDAY AHEAD OF NEXT SFC WAVE. ENHANCED CHANCE FOR PRECIP LOOKS TO BE ON THURSDAY WITH THE PASSAGE OF THIS SFC WAVE. MID LEVEL FLOW AMPLIFIES AND BECOMES NORTHWESTERLY AS THIS SFC WAVE SHIFTS EAST. FRIDAY MAY END UP BEING DRY BUT FOR NOW HAVE DIMINISHED POPS TO SLIGHT CHANCE WITH TIMING DIFFERENCES FROM VARIOUS SOLNS. BETTER CHANCE FOR PCPN DEVELOPS SATURDAY WITH NEXT SFC WAVE PIVOTING THRU GREAT LAKES. HAVE SPREAD CHANCE POPS BACK IN FRIDAY NIGHT INTO SATURDAY. THIS CHANCE CONTINUE INTO NEXT SUNDAY WITH PASSAGE OF SFC WAVE. TEMPERATURES ARE EXPECTED TO BE AT OR ABOVE NORMAL WITH HIGHS TUESDAY THRU THURSDAY RANGING FROM THE LOWER 80S FAR NORTH TO UPPER 80S/NEAR 90 SOUTH. TEMPERATURES SLIGHTLY COOLER NEXT FRIDAY/SATURDAY AND SUNDAY WITH HIGHS FROM UPR 70S/NEAR 80 NORTH TO LOWER 80S SOUTH. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... NEW TAF FORECAST REMOVES THE THREAT FOR SHOWERS/STORMS THIS AFTERNOON AT ALL SITES. WHILE ISOLD/SCT STORMS MAY BE POSSIBLE...FEEL THE BEST CHANCE OF THESE WILL BE SOUTH EAST OF ILN/CVG/LCK. THUS...RUNNING WITH SCATTERED CUMULUS AND SCT-BKN CIRRUS THROUGH THE DAY WITH MODERATE SWLY BREEZES. TONIGHT...MCS POTENTIAL STILL LOOMS COMING OUT OF THE CENTRAL MS VALLEY TOWARD THE LOWER OH VALLEY. THERE/S SOME CONCERN THAT THE NORTHERN FRINGE OF A POTENTIAL STORM COMPLEX COULD GRAZE CVG/LUK AROUND 03Z TO 04Z...BUT FOR RIGHT NOW WILL JUST GO WITH MID CLOUD AT THOSE SITES AND LET FURTHER FORECASTS DICTATE NEED TO MENTION TSRA. DID MAINTAIN MENTION OF MIST /BR/ IN MVFR CATEGORY FOR MOST SITES AS FLOW BACKS/WEAKENS AND AMPLE BOUNDARY LAYER MOISTURE REMAINS UNDER SCATTERED CLOUDS. DID ALLOW LUK TO DROP TO IFR FOR A FEW HOURS. ON MONDAY...WARM FRONT RETURNS BACK NORTH ACROSS THE AREA WITH INCREASING SWLY BREEZES AGAIN. IMPETUS FOR LARGER SCALE THUNDERSTORM DEVELOPMENT APPEARS TO BE WEST/NORTH OF THE TAF SITES THROUGH 18Z SO HAVE DRY TAFS WITH VFR CONDITIONS ON MONDAY. OUTLOOK...THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON AND AGAIN ON THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...CONIGLIO NEAR TERM...CONIGLIO SHORT TERM...CONIGLIO LONG TERM...AR AVIATION...BINAU
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
231 PM EDT SUN JUN 21 2015 .SYNOPSIS... A MEANDERING FRONT WILL BRING ON AND OFF ROUNDS OF THUNDERSTORMS THROUGH MUCH OF THE UPCOMING WEEK. && .NEAR TERM /THROUGH TONIGHT/... FAIRLY UNIFORM CU FIELD OVER THE CWA THIS AFTERNOON WITH MOIST BL IN PLACE. REMAINING DEBRIS CLOUDS HAVE SHIFTED INTO SOUTHERN COAL FIELDS AND CENTRAL VA. OTHERWISE...SWIFT MID LEVEL FLOW LEADING TO A FEW GUSTY WIND REPORTS HERE AND THERE. LATEST RAP AND HRRR MODELS BOTH SEEM TO ADVERTISE THAT THE BEST FOCUS FOR CONVECTIVE INITIATION THIS AFTERNOON WILL BE ACROSS THE SOUTHERN COAL FIELDS OF WV. MAIN AXIS OF INSTABILITY AND MOISTURE STRETCHES ACROSS CENTRAL KY AND INTO SRN WV WHICH CORRELATES WELL WITH HIRES MODELS...AND EXPECTED CONVECTIVE DEVELOPMENT. 88D RETURNS FROM 1820Z ARE JUST STARTING TO SHOW SIGNS OF DEVELOPMENT IN KY...AND VA WV BORDERS. FOR TEMPS...MADE MINOR TWEAKS TO TEMPS MAX TEMPS...LEANING A LITTLE CLOSER TO MAV NUMBERS OVER THE MET. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... WARM FRONT WILL LIFT NORTHEAST ON MONDAY...FOLLOWED BY A COLD FRONT PUSHING SOUTHEAST ON TUESDAY. FRONT WILL BECOME STATIONARY EITHER ACROSS OUR SOUTHERN COUNTIES...OR JUST SOUTH OF OUR FORECAST AREA TUESDAY NIGHT. FRONT WILL MOVE LITTLE UNTIL EARLY WEDNESDAY NIGHT...BEFORE MOVING SLOWLY BACK NORTHEAST. AS A RESULT...ON AND OFF CHANCES OF SHOWERS AND THUNDERSTORMS WILL PREVAIL THROUGH THE PERIOD. WITH WET GROUND IN PLACE...HAVE GENERALLY LEANED TOWARD THE COOLER SIDE OF THE GUIDANCE...ESPECIALLY FOR EARLY IN THIS PERIOD. && .LONG TERM /THURSDAY THROUGH SATURDAY/... NOT MUCH CHANGE IN OUR THINKING. A SERIES OF UPPER DISTURBANCES IN THE WEST TO NORTHWEST FLOW ALOFT PATTERN..WILL KEEP A FRONTAL SYSTEM MEANDERING CLOSE TO OUR AREA. IT WILL DIFFICULT TO TIME THESE DISTURBANCES AND HOW FAR THEIR FRONTS WILL GET...SO WILL KEEP A CHANCE OF SHOWERS AND STORMS EACH DAY. IT WILL CONTINUE WARM AND HUMID. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... LOW LEVEL BOUNDARY LEVELS QUITE MOIST THIS MORNING WITH 70 PLUS DP VALUES STRETCHING UP ALONG THE OHIO RIVER. WE HAVE BEEN A LITTLE SLOW TO SEE LIFTING OF STRATCU DECK BY A FEW MORE HOURS. DEBRIS CLOUD FROM PREVIOUS NIGHTS MCS HAS MORE OR LESS WASHED OUT ACROSS THE SOUTHERN COALFIELDS AND CENTRAL VIRGINIA....WHILE BL STRATCU REMAIN NORTH AND WEST. PUSHED FOCUS FOR CONVECTIVE DEVELOPMENT FURTHER SOUTH AS WEAK DISTURBANCES MOVE ACROSS...AND BEST INSTABILITY RESIDES. SFC FLOW A BIT GUSTY DURING THE AFTERNOON HOURS. KEPT GENERALLY MVFR CONDITIONS FOR OVERNIGHT HOURS...THE EXCEPTION BEING KEKN WHERE SOME BRIEF IFR CAN BE EXPECTED FOR THE EARLY MORNING. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SUNDAY... FORECAST CONFIDENCE: LOW TO MEDIUM. ALTERNATE SCENARIOS: TIMING...ANY THUNDERSTORM THAT DIRECTLY HITS AN AIRPORT THIS AFTERNOON COULD BRING IFR CONDITIONS AND STRONG WIND GUSTS. .AFTER 18Z SUNDAY... IFR POSSIBLE TUESDAY IN SHOWERS AND THUNDERSTORMS. && WV...NONE. OH...NONE. KY...NONE. VA...NONE. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...JSH/ARJ NEAR TERM...KMC SHORT TERM...JSH LONG TERM...KTB AVIATION...KMC
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
126 PM EDT SUN JUN 21 2015 .SYNOPSIS... A COLD FRONT WORKING INTO THE REGION TODAY WILL BRING THE CHANCE FOR SOME THUNDERSTORMS. UNSETTLED WEATHER WILL PERSIST THROUGH MUCH OF THE WEEK AS VARIOUS DISTURBANCES AFFECT THE REGION. && .NEAR TERM /THROUGH TONIGHT/... UPDATED DISCUSSION>>>HAVE DROPPED RAIN CHANCES A LITTLE BIT FOR THE MID/LATER AFTERNOON PER SATELLITE TRENDS AND VERY SHORT RANGE PREDICTIONS FROM THE HRRR RUNS SINCE 10Z. THINK IF ANYTHING DEVELOPS ACROSS THE FORECAST AREA THIS AFTERNOON IT WILL BE 19Z- 22Z IN CNTL/SCNTL OHIO AND MAY BUILD BACK WEST A LITTLE BIT...BUT DEARTH OF ACTIVITY ON A HUGE NUMBER OF STORM SCALE AND MESOSCALE MODELS /AND SUBSTANTIATED BY LACK OF GOOD BOUNDARY LAYER CONVERGENCE SEEN IN ANALYSIS/SATELLITE/OBS SUGGESTS ANY DEVELOPMENT WILL BE QUITE ISOLATED/SCATTERED. PREVIOUS DISCUSSION>>>FORECAST CONCERNS DEAL SQUARELY ON CONVECTIVE /AND SEVERE/ POTENTIAL THROUGH THE PEAK OF THE DIURNAL CYCLE INTO THE MID EVENING. 21.12Z KILN RAOB SAMPLED A VERY WARM LOWER TROPOSPHERE WITH 900MB TEMPS TO 26C AND STEEP LAPSE RATE/MODERATE WESTERLY FLOW ABOVE THAT MORNING INVERSION. CONVECTIVE REMNANT CLOUDS FROM NIGHTTIME MCS HAVE BEEN ERODING AND HEATING/INSOLATION IS OCCURRING BUT THICKER MID/HIGH CLOUDS CONTINUE TO LOOM OVER INDIANA. AMALGAM OF STORMSCALE GUIDANCE THIS MORNING POINTS TO WIDELY DISPARATE SCENARIOS - AND THIS IS LIKELY TIED TO WEAK/NEBULOUS FORCING AND EFFECTIVE OUTFLOWS FROM OVERNIGHT MCS ACTIVITY. RECENT NCEP HRRR RUNS ARE ADAMANT THAT THE BULK OF THE DAY REMAINS QUIET FOR THE ILN FORECAST AREA WITH INCIPIENT CONVECTIVE DEVELOPMENT OVER KY ON LEADING EDGE OF DECAYED INDIANA MCS. 21.00Z ARW-WRF WINDOW VERY SIMILAR TO THAT...AS WAS THE 21.00Z SPC/EMC WRF. THESE DATA ALL SUGGEST A FURTHER SOUTH CONVECTIVE INITIATION LIKELY DUE TO HANDLING OF MCS OUTFLOW/DEBRIS CLOUD. CONTRARILY...21.00Z STORMSCALE ENSEMBLE FROM NCAR STILL POINTING OF HIGHER PROBABILITIES OF CONVECTIVE INITIATION OVER SOUTHERN OHIO IN THE 19-20Z TIMEFRAME /ALTHOUGH THIS FORECAST A MUCH MORE MUTED VERSION OF ITS PRIOR FORECAST/ WITH A SCT-BKN CONVECTIVE LINE SAGGING INTO NRN KY THIS EVENING. THE 21.00Z SSEO LIES MORE IN LINE THE HRRR/ARW/SPC WRF - BUT DOES HAVE SOME PROBABILITIES OF STORM INITIATION/SEVERE THREAT IN FAR SRN OHIO/NRN KY. BOTTOM LINE - THERE ARE CONCERNS FOR BOUNDARY LAYER FORCING FOR CONVECTIVE INITIATION AS SFC WIND FLOW DOES NOT APPEAR OVERLY CONVERGENT. INBOUND /BUT ERODING/ DEBRIS CLOUD ALSO OF CONCERN. NEW 21.09Z SREF CALIBRATED SVR PROBS HAVE BACKED DOWN NOTABLY OVER THE FORECAST AREA - BUT ARE NONZERO. CURRENT FORECAST THINKING THAT SCT STORMS ARE POSSIBLE AFT 18Z IN SRN OHIO AND NRN KY ON ONE OR TWO RESIDUAL OUTFLOW/DIFFERENTIAL HEATING ZONES. FORECAST CAPE/SHEAR SUGGESTS ENOUGH FLOW /0-6KM SHEAR OF 25-30KT/ FOR MODEST STORM ORGANIZATION AND DCAPE/DIFFERENTIAL THETA-E SUGGESTS A WIND THREAT FIRST...WITH STEEP MID LEVEL LAPSE RATES SUGGESTING HAIL COULD BE DECENT IN THE STRONGEST CORES. LOW LEVEL SHEAR IS WEAK THUS NOT EXPECTING MUCH OF A TOR THREAT. ANY STORMS WHICH FORM WILL SINK E-SE TOWARD AND ACROSS THE OHIO RIVER THIS EVENING. NOT ENOUGH SIGNAL TO GO ANYWHERE HIGHER THAN 40-50% ON RAIN CHANCES. && .SHORT TERM /MONDAY THROUGH TUESDAY/... FRONT WHICH DROPPED IN ON SUNDAY WILL START TO LEFT BACK AS A WARM FRONT MONDAY. SOME SCT CONVECTION COULD START TO DEVELOP IN THE CINCY TRI-STATE LATE TONIGHT ON THE FRONT AND WILL TRY AND BUILD NE. A STRONG LOWS PRESSURE SYSTEM WILL RACE ACROSS THE UPPER GREAT LAKES MONDAY NIGHT. A CDFNT WILL WILL DRAG ACROSS THE REGION TUESDAY AND WILL BRING ANOTHER CHANCE OF CONVECTION. HIGHS ON MONDAY AND TUESDAY WILL RANGE FROM THE MID 80S NORTH UP TO AROUND 90 SOUTH. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... MID LEVEL RIDGE ACROSS THE SOUTHERN US WITH ACTIVE BAND OF WESTERLIES ACROSS THE NORTHERN TIER OF STATES AND GREAT LAKES TO DOMINATE THE WEATHER THIS WEEK. A SERIES OF PERTURBATIONS TO COME THRU THE WESTERLY FLOW WITH E-W SURFACE FRONTAL BOUNDARY OSCILLATING NORTH/SOUTH ACRS THE REGION. FRONT LOOKS TO FOCUS BEST CHANCE OF CONVECTION ACRS SRN FA LATER TUESDAY INTO EARLY WEDNESDAY TO LIFT BACK NORTH LATER WED INTO THURSDAY AHEAD OF NEXT SFC WAVE. MID LEVEL FLOW AMPLIFIES AND BECOMES NORTHWESTERLY AS THIS SFC WAVE SHIFTS EAST. HAVE GONE WITH A DRY FCST FRIDAY BUT CONFIDENCE IS NOT VERY HIGH. IF THIS DRY PERIOD DOES OCCUR IT LOOKS TO BE SHORT LIVED WITH NEXT WAVE PIVOTING THRU GREAT LAKES NEXT SATURDAY. HAVE SPREAD CHANCE POPS BACK IN FRIDAY NIGHT INTO SATURDAY. TEMPERATURES ARE EXPECTED TO BE AT OR ABOVE NORMAL WITH HIGHS TUESDAY THRU THURSDAY RANGING FROM THE LOWER 80S FAR NORTH TO UPPER 80S/NEAR 90 SOUTH. TEMPERATURES SLIGHTLY COOLER NEXT FRIDAY/SATURDAY WITH HIGHS FROM 80 NORTH TO MID 80S SOUTH. && .AVIATION /17Z SUNDAY THROUGH THURSDAY/... NEW TAF FORECAST REMOVES THE THREAT FOR SHOWERS/STORMS THIS AFTERNOON AT ALL SITES. WHILE ISOLD/SCT STORMS MAY BE POSSIBLE...FEEL THE BEST CHANCE OF THESE WILL BE SOUTH EAST OF ILN/CVG/LCK. THUS...RUNNING WITH SCATTERED CUMULUS AND SCT-BKN CIRRUS THROUGH THE DAY WITH MODERATE SWLY BREEZES. TONIGHT...MCS POTENTIAL STILL LOOMS COMING OUT OF THE CENTRAL MS VALLEY TOWARD THE LOWER OH VALLEY. THERE/S SOME CONCERN THAT THE NORTHERN FRINGE OF A POTENTIAL STORM COMPLEX COULD GRAZE CVG/LUK AROUND 03Z TO 04Z...BUT FOR RIGHT NOW WILL JUST GO WITH MID CLOUD AT THOSE SITES AND LET FURTHER FORECASTS DICTATE NEED TO MENTION TSRA. DID MAINTAIN MENTION OF MIST /BR/ IN MVFR CATEGORY FOR MOST SITES AS FLOW BACKS/WEAKENS AND AMPLE BOUNDARY LAYER MOISTURE REMAINS UNDER SCATTERED CLOUDS. DID ALLOW LUK TO DROP TO IFR FOR A FEW HOURS. ON MONDAY...WARM FRONT RETURNS BACK NORTH ACROSS THE AREA WITH INCREASING SWLY BREEZES AGAIN. IMPETUS FOR LARGER SCALE THUNDERSTORM DEVELOPMENT APPEARS TO BE WEST/NORTH OF THE TAF SITES THROUGH 18Z SO HAVE DRY TAFS WITH VFR CONDITIONS ON MONDAY. OUTLOOK...THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON AND AGAIN ON THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...CONIGLIO/SITES NEAR TERM...BINAU SHORT TERM...SITES LONG TERM...AR AVIATION...BINAU
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
1014 AM EDT SUN JUN 21 2015 .SYNOPSIS... A COLD FRONT WORKING INTO THE REGION TODAY WILL BRING THE CHANCE FOR SOME THUNDERSTORMS. UNSETTLED WEATHER WILL PERSIST THROUGH MUCH OF THE WEEK AS VARIOUS DISTURBANCES AFFECT THE REGION. && .NEAR TERM /THROUGH TONIGHT/... FORECAST CONCERNS DEAL SQUARELY ON CONVECTIVE /AND SEVERE/ POTENTIAL THROUGH THE PEAK OF THE DIURNAL CYCLE INTO THE MID EVENING. 21.12Z KILN RAOB SAMPLED A VERY WARM LOWER TROPOSPHERE WITH 900MB TEMPS TO 26C AND STEEP LAPSE RATE/MODERATE WESTERLY FLOW ABOVE THAT MORNING INVERSION. CONVECTIVE REMNANT CLOUDS FROM NIGHTTIME MCS HAVE BEEN ERODING AND HEATING/INSOLATION IS OCCURRING BUT THICKER MID/HIGH CLOUDS CONTINUE TO LOOM OVER INDIANA. AMALGAM OF STORMSCALE GUIDANCE THIS MORNING POINTS TO WIDELY DISPARATE SCENARIOS - AND THIS IS LIKELY TIED TO WEAK/NEBULOUS FORCING AND EFFECTIVE OUTFLOWS FROM OVERNIGHT MCS ACTIVITY. RECENT NCEP HRRR RUNS ARE ADAMANT THAT THE BULK OF THE DAY REMAINS QUIET FOR THE ILN FORECAST AREA WITH INCIPIENT CONVECTIVE DEVELOPMENT OVER KY ON LEADING EDGE OF DECAYED INDIANA MCS. 21.00Z ARW-WRF WINDOW VERY SIMILAR TO THAT...AS WAS THE 21.00Z SPC/EMC WRF. THESE DATA ALL SUGGEST A FURTHER SOUTH CONVECTIVE INITIATION LIKELY DUE TO HANDLING OF MCS OUTFLOW/DEBRIS CLOUD. CONTRARILY...21.00Z STORMSCALE ENSEMBLE FROM NCAR STILL POINTING OF HIGHER PROBABILITIES OF CONVECTIVE INITIATION OVER SOUTHERN OHIO IN THE 19-20Z TIMEFRAME /ALTHOUGH THIS FORECAST A MUCH MORE MUTED VERSION OF ITS PRIOR FORECAST/ WITH A SCT-BKN CONVECTIVE LINE SAGGING INTO NRN KY THIS EVENING. THE 21.00Z SSEO LIES MORE IN LINE THE HRRR/ARW/SPC WRF - BUT DOES HAVE SOME PROBABILITIES OF STORM INITIATION/SEVERE THREAT IN FAR SRN OHIO/NRN KY. BOTTOM LINE - THERE ARE CONCERNS FOR BOUNDARY LAYER FORCING FOR CONVECTIVE INITIATION AS SFC WIND FLOW DOES NOT APPEAR OVERLY CONVERGENT. INBOUND /BUT ERODING/ DEBRIS CLOUD ALSO OF CONCERN. NEW 21.09Z SREF CALIBRATED SVR PROBS HAVE BACKED DOWN NOTABLY OVER THE FORECAST AREA - BUT ARE NONZERO. CURRENT FORECAST THINKING THAT SCT STORMS ARE POSSIBLE AFT 18Z IN SRN OHIO AND NRN KY ON ONE OR TWO RESIDUAL OUTFLOW/DIFFERENTIAL HEATING ZONES. FORECAST CAPE/SHEAR SUGGESTS ENOUGH FLOW /0-6KM SHEAR OF 25-30KT/ FOR MODEST STORM ORGANIZATION AND DCAPE/DIFFERENTIAL THETA-E SUGGESTS A WIND THREAT FIRST...WITH STEEP MID LEVEL LAPSE RATES SUGGESTING HAIL COULD BE DECENT IN THE STRONGEST CORES. LOW LEVEL SHEAR IS WEAK THUS NOT EXPECTING MUCH OF A TOR THREAT. ANY STORMS WHICH FORM WILL SINK E-SE TOWARD AND ACROSS THE OHIO RIVER THIS EVENING. NOT ENOUGH SIGNAL TO GO ANYWHERE HIGHER THAN 40-50% ON RAIN CHANCES. && .SHORT TERM /MONDAY THROUGH TUESDAY/... FRONT WHICH DROPPED IN ON SUNDAY WILL START TO LEFT BACK AS A WARM FRONT MONDAY. SOME SCT CONVECTION COULD START TO DEVELOP IN THE CINCY TRI-STATE LATE TONIGHT ON THE FRONT AND WILL TRY AND BUILD NE. A STRONG LOWS PRESSURE SYSTEM WILL RACE ACROSS THE UPPER GREAT LAKES MONDAY NIGHT. A CDFNT WILL WILL DRAG ACROSS THE REGION TUESDAY AND WILL BRING ANOTHER CHANCE OF CONVECTION. HIGHS ON MONDAY AND TUESDAY WILL RANGE FROM THE MID 80S NORTH UP TO AROUND 90 SOUTH. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... MID LEVEL RIDGE ACROSS THE SOUTHERN US WITH ACTIVE BAND OF WESTERLIES ACROSS THE NORTHERN TIER OF STATES AND GREAT LAKES TO DOMINATE THE WEATHER THIS WEEK. A SERIES OF PERTURBATIONS TO COME THRU THE WESTERLY FLOW WITH E-W SURFACE FRONTAL BOUNDARY OSCILLATING NORTH/SOUTH ACRS THE REGION. FRONT LOOKS TO FOCUS BEST CHANCE OF CONVECTION ACRS SRN FA LATER TUESDAY INTO EARLY WEDNESDAY TO LIFT BACK NORTH LATER WED INTO THURSDAY AHEAD OF NEXT SFC WAVE. MID LEVEL FLOW AMPLIFIES AND BECOMES NORTHWESTERLY AS THIS SFC WAVE SHIFTS EAST. HAVE GONE WITH A DRY FCST FRIDAY BUT CONFIDENCE IS NOT VERY HIGH. IF THIS DRY PERIOD DOES OCCUR IT LOOKS TO BE SHORT LIVED WITH NEXT WAVE PIVOTING THRU GREAT LAKES NEXT SATURDAY. HAVE SPREAD CHANCE POPS BACK IN FRIDAY NIGHT INTO SATURDAY. TEMPERATURES ARE EXPECTED TO BE AT OR ABOVE NORMAL WITH HIGHS TUESDAY THRU THURSDAY RANGING FROM THE LOWER 80S FAR NORTH TO UPPER 80S/NEAR 90 SOUTH. TEMPERATURES SLIGHTLY COOLER NEXT FRIDAY/SATURDAY WITH HIGHS FROM 80 NORTH TO MID 80S SOUTH. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... MCS DIED OUT AS IT SWEPT THROUGH CWA EARLY THIS MORNING. IT APPEARS THAT THE 6Z NAM HAS AN IDEA WITH UPSTREAM RAIN IN CENTRAL ILLINOIS AND PROGRESSES IT THROUGH SOUTHERN INDIANA AND NORTHERN KENTUCKY IN THE EARLY AFTERNOON. SOME WEAK RETURNS ARE ALSO EXPECTED OVER SOUTHERN OHIO BUT THUNDERSTORM ACTIVITY IN THE CWA LOOKS TO BE LACKING THIS AFTERNOON. EVEN AS THE RETURNS WEAKEN OVER CENTRAL OHIO...FEW STRATOCU CLOUDS UNDER 6KFT ARE APPARENT AND THE BULK OF ANY CLOUD COVER IS OVER 10KFT. ATTEMPTED TO HAVE SHOWERS IN THE FORECAST BETWEEN 17 AND 20Z FOR MOST AREAS AND EXPECT A QUICK DISSIPATION TO ANY CLOUDS BEHIND WHAT RAIN DOES DEVELOP. WESTERLY WINDS AROUND 10KT THIS AFTERNOON WILL BECOME LIGHT AND VARIABLE OVERNIGHT AND SHOULD LEAD TO THE DEVELOPMENT OF SOME PATCHY FOG. OUTLOOK...THUNDERSTORMS WILL BE POSSIBLE TUESDAY AFTERNOON AND AGAIN ON THURSDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS...CONIGLIO/SITES NEAR TERM...BINAU SHORT TERM...SITES LONG TERM...AR AVIATION...FRANKS
AREA FORECAST DISCUSSION
NWS TULSA OK
1152 PM CDT SAT JUN 20 2015 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. FOR THE 6Z TAFS... VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGHOUT THE 24 HOUR FORECAST PERIOD. SOUTHWEST WINDS WILL INCREASE SUNDAY DURING THE DAY ACROSS THE REGION. && .PREV DISCUSSION... /ISSUED 941 PM CDT SAT JUN 20 2015/ DISCUSSION... FORECAST ON-TRACK. HRRR TAKES MINOR NORTHEAST TEXAS CONVECTION NEAR/INTO EXTREME SOUTHEASTERN ZONES LATE TONIGHT SUNDAY MORNING. LOW CHANCE POPS AT THIS TIME. GW && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...06
AREA FORECAST DISCUSSION
NWS MEDFORD OR
1135 AM PDT SUN JUN 21 2015 .UPDATE...LATEST RADAR IS SHOWING RETURNS JUST NORTH OF CHEMULT AND THE CURRENT HRRR RUN IS SHOWING QPF OVER NORTHERN KLAMATH AND NORTHWEST LAKE COUNTY AND HAVE ADDED ISOLATED THUNDERSTORMS FOR THESE AREAS STARTING NOW INTO THE AFTERNOON. LATEST SPS MESOSCALE ANALYSIS SHOWS LI`S NEAR -1 AND THERE IS SOME COOLING ALOFT AND WEAK SHORTWAVES AND THIS MAY BE ENOUGH FOR ISOLATED STORMS TO POP UP. -PETRUCELLI && .MFR WATCHES/WARNINGS/ADVISORIES... OR...NONE. CA...RED FLAG WARNING UNTIL 8 PM PDT THIS EVENING FOR CAZ285. PACIFIC COASTAL WATERS...NONE. $$
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
409 PM EDT SUN JUN 21 2015 .SYNOPSIS... OUR REGION WILL BE IN THE WESTERLY/NORTHWESTERLY FLOW ON THE NORTHERN FLANK OF A MASSIVE SUBTROPICAL RIDGE. THUS AS COLD FRONTS APPROACH THEY CAN RAPIDLY PULL IN SOME WARM MOIST AIR...TUESDAY SHOULD BE WARM AS A WAVE APPROACHES AND PULLS IN 18 TO 21C AIR AT 850 HPA. LONGER TERM IS OPTIMISTIC THAT THE WAVES SLOWLY CARVE OUT A TROUGH AND PROVIDE FOR A PROGRESSIVELY COOLER AND DRIER PERIOD. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... THE FIRST ROUND OF WEAK SHOWERS MOVED ACROSS WESTERN AND CENTRAL AREAS WITH LITTLE AFFECT. RADAR SHOWS A SECOND ROUND OF SHOWERS AND ISOLATED THUNDERSTORMS APPROACHING FROM THE NORTHWEST. TRIED TO USE BLEND AND ADD DETAIL WITH HRRR WITH THESE FEATURES. GENERAL MESSAGE GOOD CHANCE RAIN IN NORTHEASTERN AREAS 2 TO 3 PM AS THE RAIN/SHOWERS ARE ON RADAR. A SECOND SHOT IN WEST/CENTRAL AREAS BASED ON RADAR AND HRRR. HRRR QPF IS APPARENTLY GROSSLY OVER DONE....3KM GRID SIZED THUNDERSTORM PRODUCES MORE QPF THAN A SMALLER WEAKER ONE THAT TODAY MAY BE 1-2 KM LARGE. BE HIT OR MISS. SLOWLY DRY OUT AND MOSTLY CHANCE TO SLIGHT CHANCE DIMINISHES AFTER SUNSET. && .SHORT TERM /10 PM THIS EVENING THROUGH 6 PM MONDAY/... DRYING OUT OVERNIGHT DEW POINTS SLOWLY DROP AND WE SLOWLY DRY OUT. SHOULD GET MORE COMFORTABLE TOWARD MORNING. BRIGHTER TOO. THE RIDGE AND HIGH PW AIR SUPPRESSED TO OUR SOUTH MONDAY...COOLER DRIER DAY ON THE EDGE OF THE BIG SUBTROPICAL RIDGE. AT THIS TIME SUSPECT RETURN FLOW AND SURGE HIGH PW AIR AND INSTABILITY WILL HOLD OFF UNTIL EVENING HOURS. SHOULD BE RAIN FREE ACROSS MOST IF NOT ALL OF THE REGION TOMORROW UNTIL AT LEAST DINNERTIME. RELATIVELY PLEASANT SUMMER DAY. TUESDAY SHOULD BE TOASTY AS THE MOISTURE AND HEAT SURGE BACK IN... && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE NORTHERN U.S. THROUGH FRI. A HOT 594DM 500MB UPPER RIDGE EXTENING FROM THE FOUR CORNERS REGION TO THE MID TENNESSEE RIVER VALLEY ON TUESDAY...RETURN FLOW OF MOISTURE AND ABOVE NORMAL TEMPERATURES WILL MOVE INTO PA MON NIGHT/TUE. LOW PRESSURE WAVE PUSHING INTO THE GREAT LAKES MON WITH INCREASING LLJET SHOULD KICK OFF DECENT MCS TO OUR NW MON NIGHT...WHICH COULD SLIDE INTO NW MTNS BY SUNRISE TUE. DECENT W/NW FLOW PATTERN COMBINED WITH NOTABLE CAPE ON TUE /AS TEMPS SURGE INTO THE MID 80S TO LOWER 90S ACROSS THE SOUTH/ COULD BRING ROUND OF TSTMS AND SCT STRONG TO SEVERE STORMS AS COLD FRONT DROPS ACROSS CWA. SETUP IS GOOD FOR A NW FLOW EVENT...THOUGH LOW CENTERED A BIT FAR TO OUR NORTH AND DEBRIS CLOUDS FROM OVERNIGHT CONVECTION COULD DAMPEN HEATING. BUT FOR NOW...SPC HAS MUCH OF CWA IN A SLIGHT RISK FOR TUE. FRONTAL BOUNDARY SETTLES OVER MID ATLANTIC REGION MIDWEEK...WHICH SHOULD BRING SOMETHING WE HAVEN/T SEEN HERE FOR WHAT SEEMS LIKE A WHILE...A COUPLE OF DAYS OF DRIER WEATHER. TEMPS SETTLE BACK TOWARD SEASONAL NORMALS. WEAK FRONTAL BOUNDARY LIFTS BACK NORTHWARD FOR LATE WEEK AS SERIES OF WEAK WAVES RUN OVERHEAD...BRINGING BACK DAILY CHANCES FOR SHOWERS AND SCT TSTMS FOR LATE WEEK AND ESP NEXT WEEKEND. && .AVIATION /20Z SUNDAY THROUGH FRIDAY/... NEW TAFS REFLECT THE POTENTIAL SHOWERS AND ISOLATED THUNDERSTORMS AHEAD OF THE APPROACHING FRONT. MOST OF THESE STORMS WILL BE NO SIGNIFICANT CONSEQUENCE. MAINLY VFR WITH SHORT PERIODS OF MVFR IN A FEW SPOTS. WINDS HAVE BEEN GUSTY BUT SHOULD SETTLE DOWN THIS EVENING. ANY STRONG WINDS WOULD BE WITH A STRAY STRONGER THUNDERSTORM BETWEEN 19Z AND 00Z. SLOW DRYING OUT WITH AREAS PATCHY MVFR WITH OVERNIGHT FOG/HAZE. MONDAY LOOKS RELATIVELY QUIET...SURGE OF WARM AIR AHEAD OF A FRONT LATE IN THE DAY/EVENING COULD TRIGGER SOME SHOWERS AND STORMS IN THE WEST. THIS COULD BE VERY LATE IN THE DAY. WARMER HUMID AIR COULD PRODUCE PATCH FOG TUESDAY AM. BETTER CHANCE SHOWERS AND STORMS TUESDAY. OUTLOOK... MON...VFR AFTER SOME PATCHY AM MVFR. TUE...MAINLY VFR...MVFR PSBL AM FOG AND SCT SHRA/TSRA IN PM. WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...RXR AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
213 PM EDT SUN JUN 21 2015 .SYNOPSIS... OUR REGION WILL BE IN THE WESTERLY/NORTHWESTERLY FLOW ON THE NORTHERN FLANK OF A MASSIVE SUBTROPICAL RIDGE. THUS AS COLD FRONTS APPROACH THEY CAN RAPIDLY PULL IN SOME WARM MOIST AIR...TUESDAY SHOULD BE WARM AS A WAVE APPROACHES AND PULLS IN 18 TO 21C AIR AT 850 HPA. LONGER TERM IS OPTIMISTIC THAT THE WAVES SLOWLY CARVE OUT A TROUGH AND PROVIDE FOR A PROGRESSIVELY COOLER AND DRIER PERIOD. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... THE FIRST ROUND OF WEAK SHOWERS MOVED ACROSS WESTERN AND CENTRAL AREAS WITH LITTLE AFFECT. RADAR SHOWS A SECOND ROUND OF SHOWERS AND ISOLATED THUNDERSTORMS APPROACHING FROM THE NORTHWEST. TRIED TO USE BLEND AND ADD DETAIL WITH HRRR WITH THESE FEATURES. GENERAL MESSAGE GOOD CHANCE RAIN IN NORTHEASTERN AREAS 2 TO 3 PM AS THE RAIN/SHOWERS ARE ON RADAR. A SECOND SHOT IN WEST/CENTRAL AREAS BASED ON RADAR AND HRRR. HRRR QPF IS APPARENTLY GROSSLY OVER DONE....3KM GRID SIZED THUNDERSTORM PRODUCES MORE QPF THAN A SMALLER WEAKER ONE THAT TODAY MAY BE 1-2 KM LARGE. BE HIT OR MISS. SLOWLY DRY OUT AND MOSTLY CHANCE TO SLIGHT CHANCE DIMINISHES AFTER SUNSET. && .SHORT TERM /10 PM THIS EVENING THROUGH 6 PM MONDAY/... DRYING OUT OVERNIGHT DEW POINTS SLOWLY DROP AND WE SLOWLY DRY OUT. SHOULD GET MORE COMFORTABLE TOWARD MORNING. BRIGHTER TOO. THE RIDGE AND HIGH PW AIR SUPPRESSED TO OUR SOUTH MONDAY...COOLER DRIER DAY ON THE EDGE OF THE BIG SUBTROPICAL RIDGE. AT THIS TIME SUSPECT RETURN FLOW AND SURGE HIGH PW AIR AND INSTABILITY WILL HOLD OFF UNTIL EVENING HOURS. SHOULD BE RAIN FREE ACROSS MOST IF NOT ALL OF THE REGION TOMORROW UNTIL AT LEAST DINNERTIME. RELATIVELY PLEASANT SUMMER DAY. TUESDAY SHOULD BE TOASTY AS THE MOISTURE AND HEAT SURGE BACK IN... && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE LOWER 48 DURING THE LONG TERM PERIOD...AND THE DRYING OF SUNDAY EVENING INTO MONDAY WILL BE SHORT-LIVED. WITH A HOT 594DM 500 MB UPPER RIDGE CENTERED FROM THE TEXAS PANHANDLE TO THE MID TENNESSEE RIVER VALLEY ON TUESDAY...RETURN FLOW OF MOISTURE AND ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE REGION TUESDAY NIGHT AND WEDNESDAY WITH ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS BOUNDARY NOW APPEARS TO STALL OUT ALONG OR SOUTH OF THE PA/MD BORDER FOR THE REMAINDER OF THE WEEK...GIVING SOME HOPE OF A PROLONGED PERIOD OF DRIER WEATHER TO AT LEAST NORTHERN PA. HOWEVER...JUST A SLIGHT NORTHWARD OSCILLATION IN THE PATTERN WOULD NUDGE MOISTURE AND SHOWER CHANCES BACK TO THE NORTH. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... NEW TAFS REFLECT THE POTENTIAL SHOWERS AND ISOLATED THUNDERSTORMS AHEAD OF THE APPROACHING FRONT. MOST OF THESE STORMS WILL BE NO SIGNIFICANT CONSEQUENCE. MAINLY VFR WITH SHORT PERIODS OF MVFR IN A FEW SPOTS. WINDS HAVE BEEN GUSTY BUT SHOULD SETTLE DOWN THIS EVENING. ANY STRONG WINDS WOULD BE WITH A STRAY STRONGER THUNDERSTORM BETWEEN 19Z AND 00Z. SLOW DRYING OUT WITH AREAS PATCHY MVFR WITH OVERNIGHT FOG/HAZE. MONDAY LOOKS RELATIVELY QUIET...SURGE OF WARM AIR AHEAD OF A FRONT LATE IN THE DAY/EVENING COULD TRIGGER SOME SHOWERS AND STORMS IN THE WEST. THIS COULD BE VERY LATE IN THE DAY. WARMER HUMID AIR COULD PRODUCE PATCH FOG TUESDAY AM. BETTER CHANCE SHOWERS AND STORMS TUESDAY. OUTLOOK... MON...VFR AFTER SOME PATCHY AM MVFR. TUE...MAINLY VFR...MVFR PSBL AM FOG AND SCT SHRA/TSRA IN PM. WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...DEVOIR/GARTNER/MARTIN AVIATION...GRUMM
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1113 AM EDT SUN JUN 21 2015 .SYNOPSIS... OUR REGION WILL BE IN THE WESTERLY/NORTHWESTERLY FLOW ON THE NORTHERN FLANK OF A MASSIVE SUBTROPICAL RIDGE. THUS AS COLD FRONTS APPROACH THEY CAN RAPIDLY PULL IN SOME WARM MOIST AIR...TUESDAY SHOULD BE WARM AS A WAVE APPROACHES AND PULLS IN 18 TO 21C AIR AT 850 HPA. LONGER TERM IS OPTIMISTIC THAT THE WAVES SLOWLY CARVE OUT A TROUGH AND PROVIDE FOR A PROGRESSIVELY COOLER AND DRIER PERIOD. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... UPDATED FORECAST GRIDS AND THUS FORECASTS WITH LATEST GUIDANCE AND OBSERVATIONS. MOST IMPACT WAS ON IMPROVING THE SKIES AND SUNSHINE. A WELCOME SITE AFTER THE CLOUDS AND RAIN LAST EVENING. USED A BASE ENSEMBLE FOR POPS AND ADDED THE SCATTERED TEXTURE OF THE HRRR CONVECTION THIS AFTERNOON TO SHOW THE CHANCE OF SHOWERS WITH THE WEAK BOUNDARY PUSHING DRIER AIR INTO PA THIS AFTERNOON AND EVENING. THE THEME IS SHOWERS MOVE ACROSS THE NORTHERN TIER AND COULD PRODUCE SHOWERS AND THUNDERSTORMS. BEST CHANCE OF RAIN IS IN THE HRRR ACROSS OUR NORTHERN COUNTIES. LATER IT SHOWS EVEN MORE WIDELY SCATTERED SHOWERS IN SOUTHWEST AND CENTRAL. CHANCE OF RAIN...IN HRRR...IS VERY LOW IN SOUTHEAST. SOME INDICATIONS ARE AND SPC HAS AN OUTLOOK FOR THIS...SOME STORMS COULD BE STRONG TO SEVERE SO IN THUNDERSTORMS USED STRONGER VARIETY FOR WORDING. RADAR INDICATES HRRR MAY BE ON TO SOMETHING IN WEST/NW PA EARLY THIS AFTERNOON. WILL UPDATE AS NEED. && .SHORT TERM /10 PM THIS EVENING THROUGH 6 PM MONDAY/... SHOULD SEE IMPROVING CONDITIONS AS WE DRY OUT. NICE DAY MONDAY...SOME AFTERNOON CAPE COULD BRING BACK THREAT OF SCATTERED SHOWERS. THE ANEMIC COLD FRONT THAT COMES THROUGH SUNDAY GETS OVERRUN BY WARM AIR MONDAY AFTERNOON...850 HPA TEMPERATURES GO ABOVE NORMAL AGAIN BY LATER AFTERNOON AND EVENING. THE WARM ADVECTION AND INCREASING MOISTURE SUGGESTS SOME SHOWER POTENTIAL IN THE WEST. PW AND TEMPS GO BACK ABOVE NORMAL LATE MONDAY. TUESDAY SHOULD BE TOASTY! && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE LOWER 48 DURING THE LONG TERM PERIOD...AND THE DRYING OF SUNDAY EVENING INTO MONDAY WILL BE SHORT-LIVED. WITH A HOT 594DM 500 MB UPPER RIDGE CENTERED FROM THE TEXAS PANHANDLE TO THE MID TENNESSEE RIVER VALLEY ON TUESDAY...RETURN FLOW OF MOISTURE AND ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE REGION TUESDAY NIGHT AND WEDNESDAY WITH ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS BOUNDARY NOW APPEARS TO STALL OUT ALONG OR SOUTH OF THE PA/MD BORDER FOR THE REMAINDER OF THE WEEK...GIVING SOME HOPE OF A PROLONGED PERIOD OF DRIER WEATHER TO AT LEAST NORTHERN PA. HOWEVER...JUST A SLIGHT NORTHWARD OSCILLATION IN THE PATTERN WOULD NUDGE MOISTURE AND SHOWER CHANCES BACK TO THE NORTH. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... SOME RESIDUAL MVFR ABOUT THE REGION THIS MORNING. THOUGH MOST AREAS OF SCATTERED OUT. GUSTY WINDS WILL CONTINUE THROUGH MUCH OF THE DAY. TRIED TO TIME IN THE FIRST BATCH OF SHOWERS HEADED INTO WESTERN/NORTHWESTERN PA. FIRST BATCH COULD ARRIVE IN KBFD AROUND 16Z AND PERHAPS CLOSER TO 17Z IN KJST. GUIDANCE SHOWS A BROKEN LINE OF SHOWERS CROSSING NORTH-CENTRAL PA THIS AFTERNOON. SOME MORE SCATTERED THUNDERSTORMS POSSIBLE AHEAD OF THE FRONT LATER THIS AFTERNOON. SOME OF THESE STORMS HAVE THE POTENTIAL TO PRODUCE STRONG GUSTY WINDS. THINGS DRY OUT LATER THIS EVENING AND OVERNIGHT. MONDAY LOOKS RELATIVELY QUIET...SURGE OF WARM AIR AHEAD OF A FRONT LATE IN THE DAY COULD TRIGGER SOME SHOWERS AND STORMS IN THE WEST. WARMER HUMID AIR COULD PRODUCE PATCH FOG TUESDAY AM. BETTER CHANCE SHOWERS AND STORMS TUESDAY. OUTLOOK... MON...VFR. TUE...MAINLY VFR...MVFR PSBL AM FOG AND SCT SHRA/TSRA IN PM. WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...DEVOIR/GARTNER/MARTIN AVIATION...GRUMM/CERU
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1040 AM EDT SUN JUN 21 2015 .SYNOPSIS... OUR REGION WILL BE IN THE WESTERLY/NORTHWESTERLY FLOW ON THE NORTHERN FLANK OF A MASSIVE SUBTROPICAL RIDGE. THUS AS COLD FRONTS APPROACH THEY CAN RAPIDLY PULL IN SOME WARM MOIST AIR...TUESDAY SHOULD BE WARM AS A WAVE APPROACHES AND PULLS IN 18 TO 21C AIR AT 850 HPA. LONGER TERM IS OPTIMISTIC THAT THE WAVES SLOWLY CARVE OUT A TROUGH AND PROVIDE FOR A PROGRESSIVELY COOLER AND DRIER PERIOD. && .NEAR TERM /UNTIL 10 PM THIS EVENING/... UPDATED FORECAST GRIDS AND THUS FORECASTS WITH LATEST GUIDANCE AND OBSERVATIONS. MOST IMPACT WAS ON IMPROVING THE SKIES AND SUNSHINE. A WELCOME SITE AFTER THE CLOUDS AND RAIN LAST EVENING. USED A BASE ENSEMBLE FOR POPS AND ADDED THE SCATTERED TEXTURE OF THE HRRR CONVECTION THIS AFTERNOON TO SHOW THE CHANCE OF SHOWERS WITH THE WEAK BOUNDARY PUSHING DRIER AIR INTO PA THIS AFTERNOON AND EVENING. THE THEME IS SHOWERS MOVE ACROSS THE NORTHERN TIER AND COULD PRODUCE SHOWERS AND THUNDERSTORMS. BEST CHANCE OF RAIN IS IN THE HRRR ACROSS OUR NORTHERN COUNTIES. LATER IT SHOWS EVEN MORE WIDELY SCATTERED SHOWERS IN SOUTHWEST AND CENTRAL. CHANCE OF RAIN...IN HRRR...IS VERY LOW IN SOUTHEAST. SOME INDICATIONS ARE AND SPC HAS AN OUTLOOK FOR THIS...SOME STORMS COULD BE STRONG TO SEVERE SO IN THUNDERSTORMS USED STRONGER VARIETY FOR WORDING. RADAR INDICATES HRRR MAY BE ON TO SOMETHING IN WEST/NW PA EARLY THIS AFTERNOON. WILL UPDATE AS NEED. && .SHORT TERM /10 PM THIS EVENING THROUGH 6 PM MONDAY/... SHOULD SEE IMPROVING CONDITIONS AS WE DRY OUT. NICE DAY MONDAY...SOME AFTERNOON CAPE COULD BRING BACK THREAT OF SCATTERED SHOWERS. THE ANEMIC COLD FRONT THAT COMES THROUGH SUNDAY GETS OVERRUN BY WARM AIR MONDAY AFTERNOON...850 HPA TEMPERATURES GO ABOVE NORMAL AGAIN BY LATER AFTERNOON AND EVENING. THE WARM ADVECTION AND INCREASING MOISTURE SUGGESTS SOME SHOWER POTENTIAL IN THE WEST. PW AND TEMPS GO BACK ABOVE NORMAL LATE MONDAY. TUESDAY SHOULD BE TOASTY! && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE LOWER 48 DURING THE LONG TERM PERIOD...AND THE DRYING OF SUNDAY EVENING INTO MONDAY WILL BE SHORT-LIVED. WITH A HOT 594DM 500 MB UPPER RIDGE CENTERED FROM THE TEXAS PANHANDLE TO THE MID TENNESSEE RIVER VALLEY ON TUESDAY...RETURN FLOW OF MOISTURE AND ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE REGION TUESDAY NIGHT AND WEDNESDAY WITH ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS BOUNDARY NOW APPEARS TO STALL OUT ALONG OR SOUTH OF THE PA/MD BORDER FOR THE REMAINDER OF THE WEEK...GIVING SOME HOPE OF A PROLONGED PERIOD OF DRIER WEATHER TO AT LEAST NORTHERN PA. HOWEVER...JUST A SLIGHT NORTHWARD OSCILLATION IN THE PATTERN WOULD NUDGE MOISTURE AND SHOWER CHANCES BACK TO THE NORTH. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... IFR AND LOWER IS STILL PERSISTING OVER THE FAR WESTERN TAF SITES...WITH THE REMAINDER OF THE TAF SITES IN MVFR CIGS. THESE REDUCING CONDITIONS WILL CONTINUE TO IMPROVE THROUGH THE MORNING...MAINLY BETWEEN 13Z TO 15Z. ANY REMAINING PRECIPITATION WILL MOVE EASTWARD...WITH SOME SCATTERED SHOWERS POSSIBLE THROUGH THE NW LATE THIS MORNING. CONDITIONS WILL CONTINUE TO IMPROVE BY MID TO LATE MORNING AS A WEAK COLD FRONT COULD TRIGGER A ROUND OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON...BEFORE DRIER AIR MOVES IN TONIGHT INTO TOMORROW. MONDAY LOOKS RELATIVELY QUIET...WE WILL BE ON THE EDGE OF A MASSIVE RIDGE WHICH IMPLIES WARM DAYS AND MVFR POSSIBLE IN FOG/HAZE IN MORNINGS. OUTLOOK... MON...GENERALLY VFR. TUE...REDUCTIONS PSBL IN SCT SHRA/TSRA. WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM SHORT TERM...GRUMM LONG TERM...DEVOIR/GARTNER/MARTIN AVIATION...CERU/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
811 AM EDT SUN JUN 21 2015 .SYNOPSIS... SHOWERS FROM THE REMNANTS OF TROPICAL STORM WILL WILL MOVE AWAY FROM THE REGION TODAY. MEANWHILE...A COLD FRONT WILL APPROACH AND MOVE INTO THE KEYSTONE STATE LATER TODAY. A MUCH STRONGER COLD FRONT WILL MOVE ACROSS THE STATE ON TUESDAY. TEMPERATURES WILL WARM WELL INTO THE 90S ON TUESDAY...BEFORE COOLER AIR MOVES IN BY MID WEEK. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... CLEANED UP THE GRIDS TO SHOW THE CLEAR SLOT BETWEEN THE REMNANTS OF BILL OFF THE COAST AND THE SHORT WAVES AND CLOUDS APPROACHING FROM THE WEST. MOST GUIDANCE AND DATA SHOWS A STRONG MESO RIDGE AND OF COURSE SUBSIDENCE OVER OUR REGION. A GOOD SLICE OF CENTRAL PA IS MOSTLY CLEAR...THOUGH IN THE MOUNTAINS LOW CLOUDS ARE RUSHING IN TO FILL THE GAPS. CENTRAL AND EASTERN AREAS SHOULD BE RAIN FREE THIS AM. SHORT WAVE TO WEST AND A FORECAST SURGE OF SLIGHTLY HIGHER PW...PRETTY HIGH ALREADY...AND SOME CAPE ALONG WITH A STRONG LOW- LEVEL JET IMPLY CONVECTION AND PERHAPS STRONG CONVECTION THIS AFTERNOON WITH THIS SYSTEM. THE 10Z HRRR IS SHOWING WIDELY SCATTERED CONVECTION AT THIS TIME. NOT VERY ORGANIZED. BUT THE FEATURES THEMSELVES HAD PUT SW PORTIONS OF PA IN A SLIGHT RISK THIS AFTERNOON. KEPT GENERAL THUNDER WITH STRONG STORMS POTENTIAL IN FORECAST. NOT SURE EXACTLY WHERE. PERHAPS LATER HRRR RUNS WILL TEND TO ORGANIZE THIS. && .SHORT TERM /8 PM THIS EVENING THROUGH 6 PM MONDAY/... BEHIND ANY LINGERING SHOWERS AND STORMS...WE BEGIN TO DRY OUT AND OVERNIGHT THE PW FINALLY DROPS. THE STICKY EVENING IN THE CENTRAL AND EASTERN AREAS SHOULD GIVE WAY TO A PLEASANT AM MONDAY. SHOULD BE A RELATIVELY DRY BUT NEAR NORMAL SUMMER DAY. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE LOWER 48 DURING THE LONG TERM PERIOD...AND THE DRYING OF SUNDAY EVENING INTO MONDAY WILL BE SHORT-LIVED. WITH A HOT 594DM 500 MB UPPER RIDGE CENTERED FROM THE TEXAS PANHANDLE TO THE MID TENNESSEE RIVER VALLEY ON TUESDAY...RETURN FLOW OF MOISTURE AND ANOTHER FRONTAL SYSTEM WILL MOVE ACROSS THE REGION TUESDAY NIGHT AND WEDNESDAY WITH ANOTHER CHANCE OF SHOWERS AND THUNDERSTORMS. THIS BOUNDARY NOW APPEARS TO STALL OUT ALONG OR SOUTH OF THE PA/MD BORDER FOR THE REMAINDER OF THE WEEK...GIVING SOME HOPE OF A PROLONGED PERIOD OF DRIER WEATHER TO AT LEAST NORTHERN PA. HOWEVER...JUST A SLIGHT NORTHWARD OSCILLATION IN THE PATTERN WOULD NUDGE MOISTURE AND SHOWER CHANCES BACK TO THE NORTH. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... IFR AND LOWER IS STILL PERSISTING OVER THE FAR WESTERN TAF SITES...WITH THE REMAINDER OF THE TAF SITES IN MVFR CIGS. THESE REDUCING CONDITIONS WILL CONTINUE TO IMPROVE THROUGH THE MORNING...MAINLY BETWEEN 13Z TO 15Z. ANY REMAINING PRECIPITATION WILL MOVE EASTWARD...WITH SOME SCATTERED SHOWERS POSSIBLE THROUGH THE NW LATE THIS MORNING. CONDITIONS WILL CONTINUE TO IMPROVE BY MID TO LATE MORNING AS A WEAK COLD FRONT COULD TRIGGER A ROUND OF SHOWERS AND THUNDERSTORMS LATER THIS AFTERNOON...BEFORE DRIER AIR MOVES IN TONIGHT INTO TOMORROW. MONDAY LOOKS RELATIVELY QUIET...WE WILL BE ON THE EDGE OF A MASSIVE RIDGE WHICH IMPLIES WARM DAYS AND MVFR POSSIBLE IN FOG/HAZE IN MORNINGS. OUTLOOK... MON...GENERALLY VFR. TUE...REDUCTIONS PSBL IN SCT SHRA/TSRA. WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...GRUMM NEAR TERM...GRUMM/DEVOIR SHORT TERM...GRUMM/DEVOIR/MARTIN LONG TERM...DEVOIR/GARTNER/MARTIN AVIATION...CERU/MARTIN
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1037 PM EDT MON JUN 22 2015 .SYNOPSIS... ONG HIGH PRESSURE WILL PERSIST ACROSS THE REGION THROUGH THE MIDDLE OF THE WEEK MAINTAINING WELL ABOVE NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH TUESDAY/... AS OF 1030 PM EDT...AREA REMAINS CLEAR OF SHOWERS...AND WITH LIGHT AND VARIABLE WINDS. HRRR HAS SOME LIGHT SHOWERS IN WESTERN ZONES...BUT THERE IS NO SIGN OF THEM IN REALITY. ONLY UPDATE TO NEAR TERM FORECAST IS FOR TEMPERATURES...TO BLEND IN LATEST OBSERVATIONS. AS OF 800 PM EDT...SHOWERS HAVE ENDED AROUND THE AREA AND FURTHER CONVECTIVE ACTIVITY IS NOT EXPECTED TONIGHT DUE TO COOLING OF THE BOUNDARY LAYER...EXCEPT FOR SOME RESIDUAL SHOWERS THAT MAY DRIFT INTO THE MOUNTAINOUS AREAS OF WESTERN NORTH CAROLINA. COLD POOL FROM STORM OUTFLOWS HAS REDUCED THE TEMPERATURES IN SOME AREAS...AND HAVE ADJUSTED THE TEMPERATURE FORECAST TO ACCOUNT FOR THIS EFFECT. WINDS WILL BE LIGHT AND VARIABLE WITH OCCASIONAL WEAK GUSTS IN SOME AREAS FROM OLD OUTFLOW BOUNDARIES. FOG IS NOT FORECAST FOR TOMORROW MORNING DUE TO REDUCED BOUNDARY LAYER MOISTURE FOLLOWING MONDAYS DEEP MIX-OUT OF SURFACE MOISTURE. AS OF 430 PM EDT...SOME STRONG THUNDERSTORMS HAVE DEVELOPED OVER HIGHER TERRAIN AREAS OF WESTERN NORTH CAROLINA AND ADJACENT AREAS TO THE EAST. HRRR GUIDANCE HAS ACTIVITY CONTINUING BUT MOVING OFF OF THE MOUNTAINS INTO SOUTH CAROLINA AND DECREASING AFTER 0Z. ADJUST POP AND WEATHER FOR LATEST RADAR AND CAM TRENDS. ALSO ADJUSTED TEMPERATURES TO REDUCE TEMPERATURES IN RAIN-AFFECTED AREAS. AS OF 230 PM EDT...EXPECT THE GRADUAL EXPANSION OF CVRG ACRS THE MTNS TO CONTINUE THROUGH LATE AFTERNOON WITH THE RISK OF ISOLATED ACTIVITY IN THE PIEDMONT. DIURNALLY DRIVEN DEEP CONVECTION WILL WANE WITH LOSS OF HTG THIS EVENING FOLLOWED BY A FAIR OVERNIGHT PERIOD. THE PATTERN LOOKS TO BE NOMINALLY LESS SUPPRESSIVE ON TUESDAY WITH SLIGHTLY BETTER LLVL MOISTURE AND MEAN FLOW. FOR NOW...WILL PLAN ON RAMPING UP TO SCATTERED DIURNAL MTN CVRG AND ISOLATED ELSEWHERE. TEMPERATURES WILL BE NEAR PERSISTENCE...PEAKING NEAR RECORD LEVELS AGAIN TOMORROW. SFC DWPTS SHOULD BE ABLE TO MIX LOWER INTO/THRU THE 60S...KEEPING PIEDMONT HEAT INDEX VALUES BELOW ADVISORY THRESHOLD. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 205 PM MONDAY...A COLD FRONT TRAILING FROM A LOW IN EASTERN CANADA WILL BE LOSING STEAM AS IT GRADUALLY PUSHES TOWARD THE WESTERN CAROLINAS AND NE GA. THE 12Z NAM/GFS ARE SIMILAR IN ALLOWING WHAT IS LEFT OF THE FRONT TO DROP INTO THE LEE TROUGH EARLY WED EXTENDING FROM UPSTATE SC...SW INTO NE GA. THE WEAK BOUNDARY IS FORECAST TO REMAIN QUASI-STATIONARY ACROSS THE AREA INTO WED NIGHT BEFORE MOVING NE AS A WARM FRONT ON THU AS ANOTHER LOW MOVES INTO THE LOWER GREAT LAKES. ALOFT THE UPPER HIGH OVER THE SOUTHERN PLAINS IS FORECAST TO NOSE EASTWARD INTO THE SOUTHERN APPALACHIANS THROUGH THU WHICH WILL KEEP THICKNESSES HIGH WHICH SUPPORT A CONTINUATION OF THE HOT TEMPS. IN REGARD TO SENSIBLE WEATHER...ASSOCIATED CONVECTION WITH THE FRONTAL BOUNDARY IS FORECAST TO MAKE A RUN AT THE MOUNTAINS TUE EVENING...BUT AS IS USUALLY THE CASE THE THUNDERSTORM ACTIVITY IS FORECAST TO DIMINISH AS IT TRIES TO TRAVERSE THE MOUNTAINS IN A DIMINISHING CAPE ENVIRONMENT. ON WED...MODEL RESPONSE FOR CONVECTIVE DEVLOPMENT IS RATHER MUTED OUTSIDE THE MOUNTAINS AS PROFILES EXHIBIT SOME DRYING AND QUITE A BIT OF CIN TO OVERCOME. LOOKS LIKE ISOLATED STORMS AT BEST THERE. THE MOUNTAINS ARE A DIFFERENT STORY WITH SBCAPES FORECAST TO EXCEED 2000J WITH LESS CIN TO OVERCOME. PLUS SOME UPSTREAM CONVECTION MAY MAKE A RUN AT THE MOUNTAINS. HENCE...WILL HAVE SOLID SCT TYPE POPS ALL ACROSS THE HIGH TERRAIN. MOUNTAIN STORMS MAY SLIP INTO THE ADJACENT FOOTHILLS AND EVEN THE PIEDMONT WED EVENING...SO WILL HAVE POPS INCREASING THERE WED EVENING. GFS LOOKS OVERDONE WITH THE AMOUNT OF CONVECTION OUTSIDE THE MOUNTAINS WED NIGHT...SO WILL TREND FORECAST TOWARD NAM/SREF WHICH ARE CONSIDERABLY DRYER. ON THU...A SIMILAR SCENARIO IS EXPECTED TO WED EVEN WITH THE WEAK BOUNDARY MOVING OUT OF THE AREA. FORECAST SOUNDINGS AGAIN EXHIBIT CONSIDERABLE CAPE...BUT PROFILES AGAIN SHOW ENOUGH CIN OUTSIDE THE MOUNTAINS TO LIMIT CONVECTIVE INITIATION. WILL AGAIN FEATURE SCT TYPE POPS ACROSS THE MOUNTAINS THU AFTERNOON IN STRONG DIFFERENTIAL HEATING ENVIORNMENT. TEMPS WILL REMAIN HOT AND WELL ABOVE CLIMO EACH DAY BUT BELOW RECORD LEVELS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 230 PM EDT MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON FRIDAY WITH A LARGE SCALE PATTERN SHIFT IN PROGRESS. HEIGHTS GRADUALLY LOWER THRU THE FIRST PART OF THE PERIOD OVER THE SOUTHEAST WHILE UPPER RIDGING STEEPENS OVER THE WESTERN CONUS. BY SUNDAY...THE UPPER PATTERN IS VERY AMPLIFIED WITH A FAIRLY DEEP UPPER TROF OVER THE EASTERN CONUS AND VERY STEEP RIDGING OVER THE WEST. THIS PATTERN APPEARS LIKELY TO HOLD WELL BEYOND DAY 7. AT THE SFC...THE BERMUDA HIGH WILL PERSIST OVER THE REGION THRU THE PERIOD WITH NUMEROUS WEAK LOWS BEING GENERATED TO OUR WEST AND PROPAGATING EASTWARD. ON FRIDAY...THE MODELS CONTINUE TO GENERATE SOME DEGREE OF LEE TROFFING DURING THE LATER PART OF THE DAY/NIGHT AS A GREAT LAKES LOW MOVES WELL NORTHEAST OF THE CWFA. ON SAT...ANOTHER LOW TRIES TO SPIN UP IN THE VICINITY OF THE FCST AREA OR JUST TO OUR NE AND THEN SLOWLY PROPAGATE NE AND OFF THE NEW ENGLAND COAST. A BROAD AREA OF DEEPER LYR MOISTURE ASSOCIATED WITH THE LOW WILL SPREAD OVER THE FCST AREA BY EARLY SAT AND REMAIN OVER THE CWFA THRU ROUGHLY THE FIRST HALF OF SUN BEFORE MOVING OFF THE CAROLINA COAST. WEAK HIGH PRESSURE BRIEFLY SPREADS BACK OVER THE AREA IN THE LOWS WAKE FOR MONDAY. AS FOR THE SENSIBLE FCST...DIURNAL CONVECTION IS POSSIBLE EACH DAY WITH CHANCES GENERALLY HIGHER OVER THE MTS AND NC FOOTHILLS. CHANCES INCREASE FOR SAT AND SUN WITH THE INCREASING DEEP LYR MOISTURE OVER THE REGION AND BETTER UPPER LVL SUPPORT OVERHEAD. TEMPS START OUT ABOVE CLIMATOLOGY AND GRADUALLY DECREASE THRU THE PERIOD WITH HIGH TEMPS ENDING A FEW DEGREES BELOW NORMAL. && .AVIATION /03Z TUESDAY THROUGH SATURDAY/... AT KCLT...CONVECTIVE ACTIVITY HAS CEASED WITH LOSS OF HEATING THIS EVENING. FAIR CONDITIONS CURRENTLY PREVAIL...AND NO RESTRICTIONS ARE ANTICIPATED THROUGH TOMORROW MORNING. OCCASIONAL LIGHT WIND GUSTS WILL BE POSSIBLE DUE TO OLD STORM OUTFLOWS. ELSEWHERE...CONDITIONS ARE GENERALLY VFR WITH ONLY VERY WIDELY SCATTERED LIGHT SHOWERS STILL PERSISTING. THERE IS LESS CHANCE OF FOG TUESDAY MORNING IN LOW LYING AREAS DUE TO DRYING OF THE BOUNDARY LAYER FROM THE DEEP MIXING EXPERIENCED ON TUESDAY. ON TUESDAY AFTERNOON...FAIR WEATHER CUMULUS IS EXPECTED WITH BASES DOWN TO 5000 FEET AGL WITH SOME POSSIBILITY OF THUNDERSTORMS...ESPECIALLY OVER THE HIGHER TERRAIN. CHANCES FOR THUNDER DECREASES ON TUESDAY DUE TO SOME CONVECTIVE INHIBITION FROM SUBSIDENCE IN THE FORECAST SOUNDINGS...AND NO OBVIOUS LIFTING MECHANISM. OUTLOOK...ISOLD TO SCT DIURNAL TSTM CHANCES WILL CONTINUE THROUGH THE WEEK IN THE WARM AIRMASS. PRECIPITATION CHANCES WILL INCREASE LATE IN THE WEEK AS A FRONT APPROACHES FROM THE NW. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND MOST LIKELY IN THE MTN VALLEYS. CONFIDENCE TABLE... 02-08Z 08-14Z 14-20Z 20-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% MED 79% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JPT NEAR TERM...CSH/WJM SHORT TERM...LG LONG TERM...JP/JPT AVIATION...WJM CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
823 PM EDT MON JUN 22 2015 .SYNOPSIS... ONG HIGH PRESSURE WILL PERSIST ACROSS THE REGION THROUGH THE MIDDLE OF THE WEEK MAINTAINING WELL ABOVE NORMAL TEMPERATURES. A BROAD UPPER LEVEL TROF WILL MOVE OVER THE REGION OVER THE WEEKEND RETURNING TEMPERATURES TO SEASONAL LEVELS BY SUNDAY AND INCREASING CHANCES FOR WIDESPREAD SHOWERS AND THUNDERSTORMS. && .NEAR TERM /THROUGH TUESDAY/... AS OF 800 PM EDT...SHOWERS HAVE ENDED AROUND THE AREA AND FURTHER CONVECTIVE ACTIVITY IS NOT EXPECTED TONIGHT DUE TO COOLING OF THE BOUNDARY LAYER...EXCEPT FOR SOME RESIDUAL SHOWERS THAT MAY DRIFT INTO THE MOUNTAINOUS AREAS OF WESTERN NORTH CAROLINA. COLD POOL FROM STORM OUTFLOWS HAS REDUCED THE TEMPERATURES IN SOME AREAS...AND HAVE ADJUSTED THE TEMPERATURE FORECAST TO ACCOUNT FOR THIS EFFECT. WINDS WILL BE LIGHT AND VARIABLE WITH OCCASIONAL WEAK GUSTS IN SOME AREAS FROM OLD OUTFLOW BOUNDARIES. FOG IS NOT FORECAST FOR TOMORROW MORNING DUE TO REDUCED BOUNDARY LAYER MOISTURE FOLLOWING MONDAYS DEEP MIX-OUT OF SURFACE MOISTURE. AS OF 430 PM EDT...SOME STRONG THUNDERSTORMS HAVE DEVELOPED OVER HIGHER TERRAIN AREAS OF WESTERN NORTH CAROLINA AND ADJACENT AREAS TO THE EAST. HRRR GUIDANCE HAS ACTIVITY CONTINUING BUT MOVING OFF OF THE MOUNTAINS INTO SOUTH CAROLINA AND DECREASING AFTER 0Z. ADJUST POP AND WEATHER FOR LATEST RADAR AND CAM TRENDS. ALSO ADJUSTED TEMPERATURES TO REDUCE TEMPERATURES IN RAIN-AFFECTED AREAS. AS OF 230 PM EDT...EXPECT THE GRADUAL EXPANSION OF CVRG ACRS THE MTNS TO CONTINUE THROUGH LATE AFTERNOON WITH THE RISK OF ISOLATED ACTIVITY IN THE PIEDMONT. DIURNALLY DRIVEN DEEP CONVECTION WILL WANE WITH LOSS OF HTG THIS EVENING FOLLOWED BY A FAIR OVERNIGHT PERIOD. THE PATTERN LOOKS TO BE NOMINALLY LESS SUPPRESSIVE ON TUESDAY WITH SLIGHTLY BETTER LLVL MOISTURE AND MEAN FLOW. FOR NOW...WILL PLAN ON RAMPING UP TO SCATTERED DIURNAL MTN CVRG AND ISOLATED ELSEWHERE. TEMPERATURES WILL BE NEAR PERSISTENCE...PEAKING NEAR RECORD LEVELS AGAIN TOMORROW. SFC DWPTS SHOULD BE ABLE TO MIX LOWER INTO/THRU THE 60S...KEEPING PIEDMONT HEAT INDEX VALUES BELOW ADVISORY THRESHOLD. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 205 PM MONDAY...A COLD FRONT TRAILING FROM A LOW IN EASTERN CANADA WILL BE LOSING STEAM AS IT GRADUALLY PUSHES TOWARD THE WESTERN CAROLINAS AND NE GA. THE 12Z NAM/GFS ARE SIMILAR IN ALLOWING WHAT IS LEFT OF THE FRONT TO DROP INTO THE LEE TROUGH EARLY WED EXTENDING FROM UPSTATE SC...SW INTO NE GA. THE WEAK BOUNDARY IS FORECAST TO REMAIN QUASI-STATIONARY ACROSS THE AREA INTO WED NIGHT BEFORE MOVING NE AS A WARM FRONT ON THU AS ANOTHER LOW MOVES INTO THE LOWER GREAT LAKES. ALOFT THE UPPER HIGH OVER THE SOUTHERN PLAINS IS FORECAST TO NOSE EASTWARD INTO THE SOUTHERN APPALACHIANS THROUGH THU WHICH WILL KEEP THICKNESSES HIGH WHICH SUPPORT A CONTINUATION OF THE HOT TEMPS. IN REGARD TO SENSIBLE WEATHER...ASSOCIATED CONVECTION WITH THE FRONTAL BOUNDARY IS FORECAST TO MAKE A RUN AT THE MOUNTAINS TUE EVENING...BUT AS IS USUALLY THE CASE THE THUNDERSTORM ACTIVITY IS FORECAST TO DIMINISH AS IT TRIES TO TRAVERSE THE MOUNTAINS IN A DIMINISHING CAPE ENVIRONMENT. ON WED...MODEL RESPONSE FOR CONVECTIVE DEVLOPMENT IS RATHER MUTED OUTSIDE THE MOUNTAINS AS PROFILES EXHIBIT SOME DRYING AND QUITE A BIT OF CIN TO OVERCOME. LOOKS LIKE ISOLATED STORMS AT BEST THERE. THE MOUNTAINS ARE A DIFFERENT STORY WITH SBCAPES FORECAST TO EXCEED 2000J WITH LESS CIN TO OVERCOME. PLUS SOME UPSTREAM CONVECTION MAY MAKE A RUN AT THE MOUNTAINS. HENCE...WILL HAVE SOLID SCT TYPE POPS ALL ACROSS THE HIGH TERRAIN. MOUNTAIN STORMS MAY SLIP INTO THE ADJACENT FOOTHILLS AND EVEN THE PIEDMONT WED EVENING...SO WILL HAVE POPS INCREASING THERE WED EVENING. GFS LOOKS OVERDONE WITH THE AMOUNT OF CONVECTION OUTSIDE THE MOUNTAINS WED NIGHT...SO WILL TREND FORECAST TOWARD NAM/SREF WHICH ARE CONSIDERABLY DRYER. ON THU...A SIMILAR SCENARIO IS EXPECTED TO WED EVEN WITH THE WEAK BOUNDARY MOVING OUT OF THE AREA. FORECAST SOUNDINGS AGAIN EXHIBIT CONSIDERABLE CAPE...BUT PROFILES AGAIN SHOW ENOUGH CIN OUTSIDE THE MOUNTAINS TO LIMIT CONVECTIVE INITIATION. WILL AGAIN FEATURE SCT TYPE POPS ACROSS THE MOUNTAINS THU AFTERNOON IN STRONG DIFFERENTIAL HEATING ENVIORNMENT. TEMPS WILL REMAIN HOT AND WELL ABOVE CLIMO EACH DAY BUT BELOW RECORD LEVELS. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 230 PM EDT MONDAY...THE MEDIUM RANGE FCST PICKS UP AT 00Z ON FRIDAY WITH A LARGE SCALE PATTERN SHIFT IN PROGRESS. HEIGHTS GRADUALLY LOWER THRU THE FIRST PART OF THE PERIOD OVER THE SOUTHEAST WHILE UPPER RIDGING STEEPENS OVER THE WESTERN CONUS. BY SUNDAY...THE UPPER PATTERN IS VERY AMPLIFIED WITH A FAIRLY DEEP UPPER TROF OVER THE EASTERN CONUS AND VERY STEEP RIDGING OVER THE WEST. THIS PATTERN APPEARS LIKELY TO HOLD WELL BEYOND DAY 7. AT THE SFC...THE BERMUDA HIGH WILL PERSIST OVER THE REGION THRU THE PERIOD WITH NUMEROUS WEAK LOWS BEING GENERATED TO OUR WEST AND PROPAGATING EASTWARD. ON FRIDAY...THE MODELS CONTINUE TO GENERATE SOME DEGREE OF LEE TROFFING DURING THE LATER PART OF THE DAY/NIGHT AS A GREAT LAKES LOW MOVES WELL NORTHEAST OF THE CWFA. ON SAT...ANOTHER LOW TRIES TO SPIN UP IN THE VICINITY OF THE FCST AREA OR JUST TO OUR NE AND THEN SLOWLY PROPAGATE NE AND OFF THE NEW ENGLAND COAST. A BROAD AREA OF DEEPER LYR MOISTURE ASSOCIATED WITH THE LOW WILL SPREAD OVER THE FCST AREA BY EARLY SAT AND REMAIN OVER THE CWFA THRU ROUGHLY THE FIRST HALF OF SUN BEFORE MOVING OFF THE CAROLINA COAST. WEAK HIGH PRESSURE BRIEFLY SPREADS BACK OVER THE AREA IN THE LOWS WAKE FOR MONDAY. AS FOR THE SENSIBLE FCST...DIURNAL CONVECTION IS POSSIBLE EACH DAY WITH CHANCES GENERALLY HIGHER OVER THE MTS AND NC FOOTHILLS. CHANCES INCREASE FOR SAT AND SUN WITH THE INCREASING DEEP LYR MOISTURE OVER THE REGION AND BETTER UPPER LVL SUPPORT OVERHEAD. TEMPS START OUT ABOVE CLIMATOLOGY AND GRADUALLY DECREASE THRU THE PERIOD WITH HIGH TEMPS ENDING A FEW DEGREES BELOW NORMAL. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... AT KCLT...CONVECTIVE ACTIVITY HAS CEASED WITH LOSS OF HEATING THIS EVENING. FAIR CONDITIONS CURRENTLY PREVAIL...AND NO RESTRICTIONS ARE ANTICIPATED THROUGH TOMORROW MORNING. OCCASIONAL LIGHT WIND GUSTS WILL BE POSSIBLE DUE TO OLD STORM OUTFLOWS. ELSEWHERE...CONDITIONS ARE GENERALLY VFR WITH ONLY VERY WIDELY SCATTERED LIGHT SHOWERS STILL PERSISTING. THERE IS LESS CHANCE OF FOG TUESDAY MORNING IN LOW LYING AREAS DUE TO DRYING OF THE BOUNDARY LAYER FROM THE DEEP MIXING EXPERIENCED ON TUESDAY. ON TUESDAY AFTERNOON...FAIR WEATHER CUMULUS IS EXPECTED WITH BASES DOWN TO 5000 FEET AGL WITH SOME POSSIBILITY OF THUNDERSTORMS...ESPECIALLY OVER THE HIGHER TERRAIN. CHANCES FOR THUNDER DECREASES ON TUESDAY DUE TO SOME CONVECTIVE INHIBITION FROM SUBSIDENCE IN THE FORECAST SOUNDINGS...AND NO OBVIOUS LIFTING MECHANISM. OUTLOOK...ISOLD TO SCT DIURNAL TSTM CHANCES WILL CONTINUE THROUGH THE WEEK IN THE WARM AIRMASS. PRECIPITATION CHANCES WILL INCREASE LATE IN THE WEEK AS A FRONT APPROACHES FROM THE NW. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE...PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY...AND MOST LIKELY IN THE MTN VALLEYS. CONFIDENCE TABLE... 00-06Z 06-12Z 12-18Z 18-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 94% HIGH 80% HIGH 91% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...JPT NEAR TERM...CSH/WJM SHORT TERM...LG LONG TERM...JP/JPT AVIATION...WJM CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
148 PM EDT SUN JUN 21 2015 .SYNOPSIS... DEEP HIGH PRESSURE WILL BUILD BACK ACROSS THE REGION TODAY AND REMAIN THROUGH THE MIDDLE OF THE WEEK. HOT TEMPERATURES WILL ALSO RETURN AS A STALLED FRONT REMAINS NORTH OF THE FORECAST AREA. BY THE END OF THE WORK WEEK...THE HOT PATTERN IS EXPECTED TO BREAK DOWN AS A TROUGH MOVES SOUTH OUT OF CANADA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 145 PM EDT SUNDAY...CURRENT FCST REMAINS ON TRACK THEREFORE NO CHANGES WERE MADE TO THE IMMEDIATE NEAR TERM. FULL FCST DISCUSSION TO FOLLOW WITHIN THE HOUR. PREVIOUS DISCUSSION... 430 AM EDT UPDATE...CURRENT NEAR TERM FCST IS IN GOOD SHAPE. MADE MINOR TWEAKS TO HR/LY TEMPS. ADDED AFTERNOON ISOL TSTMS ACROSS THE WRN UPSTATE AND NE GA BASED ON LATEST CAM AND RAP TRENDS TOWARD LESS CCL-LFC CIN LEVELS. THE LARGE SCALE PATTERN SHIFTS BACK INTO A MORE NORMAL SUMMERTIME CONFIG TODAY. SUBTROPICAL RIDGING WILL REASSERT ITSELF ACROSS THE SE CONUS CREATING A DIFFUSE WIND PROFILE ALOFT. CROSS SECTIONS SHOW DEEP NEGATIVE OMEGA OUTSIDE THE MTNS DURING THE AFTERNOON WITH LIMITED AVAILABLE LLVL MOISTURE. YET THE OP MODELS ARE MIXED WRT TO AMOUNT OF PARCEL DESTABILIZATION. THE NAM SHOWS A POTENTIAL OF THE SUBS INVERSION BEING BROKE AND ISOL EXPLOSIVE STORMS POSSIBLE OVER THE NON/MTNS. THE NAM ALSO HOLDS ONTO SOME MEASURE OF CIN ARND THE CCL THO. THE GFS ON THE OTHER HAND HAS UNBREAKABLE SBCIN AND NO POTENTIAL FOR SIGFNT CONVECTION. WENT WITH A BLEND OF THE RAW MODELS FOR POP WHICH KEEPS LESS THAN ISOL NON/MTNS ANS ISOL/SCT MTNS. THIS AGREES WELL WITH THE SREF OUTPUT AND THE LATEST CAMS...BUT FUTURE UPDATES COULD INTRODUCE ISOL CONVEC NON/MTNS. MAX TEMPS WILL REACH A FEW DEGREES WARMER THAN YESTERDAY...LIKELY M90S EAST AND U80S MTN VALLEYS. THE BEST AFTERNOON TD MIXING WILL OCCUR ACROSS THE ERN ZONES WHICH WILL KEEP MENTION OF HI/S OUT OF THE HWO. THE OVERNIGHT WILL FEATURE A QUICK REDUCTION OF DEBRIS CLOUDS AND STEEP SFC-BASED INVERSIONS. MTN VALLEYS...MAINLY THE FRENCH BROAD AND LITTLE TN...WILL ONCE AGAIN BE SUBJECT TO FG/BR ISSUES ARND DAYBREAK...ESP WHERE PRECIP FALLS THIS EVENING. EVEN WITH GOOD RAD COOLING THE ATMOS REMAINS RATHER STAGNANT WRT MIXING RATIOS...THUS MINS WILL REMAIN A COUPLE CATS ABOVE NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 245 AM EDT SUNDAY...A FLAT UPPER RIDGE WILL BUILD FROM THE SOUTHERN PLAINS TO THE SOUTHERN APPALACHIANS ON MONDAY. AN MCS ORIGINATING IN THE UPPER MIDWEST MAY PASS JUST N OF THE AREA MONDAY NIGHT. OTHERWISE...ISOLD CONVECTION SHOULD BE CONFINED IN AND NEAR THE MTNS IN LOW LEVEL WIND FIELD CONVERGENCE DURING THE DIURNALLY FAVORED AFTERNOON AND EVENING PERIODS. TEMPERATURES WILL INCREASE ONCE AGAIN UNDER THE BUILDING RIDGE WITH SOME HEAT INDEX VALUES REACHING 100 TO 105 IN THE SOUTHEAST HALF MON AFTN. STRONG UPPER HEIGHTS WILL REMAIN IN PLACE ON TUE AS THE BELT OF BETTER WESTERLIES STAYS JUST NORTH OF THE FORECAST AREA. 850 MB WINDS WILL TURN MORE WESTERLY AND A PIEDMONT SFC TROUGH SHOULD BECOME A BIT MORE PROMINENT. HOWEVER...MODEL PROFILES RETAIN QUITE A BIT OF CAPPING AND NEGATIVE AREA ALOFT SO CONVECTIVE COVERAGE WILL LIKELY BE MINIMIZED. WILL CONFINED ISOLD COVERAGE TO THE MTNS...BUT TSTMS WILL BE STRONG ANY PLACE THEY MANAGE TO FORM. MAX TEMPS WILL APPROACH 100 MAINLY ALONG/SOUTHEAST OF INTERSTATE 85. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 255 AM EDT SUNDAY...STRONG RIDGING CONTINUES ON WED BUT WITH A POSSIBLE MCS TRACK SETTING UP IN THE WNW FLOW FROM THE MIDWEST TO THE NC/VA LINE ALONG A STALLED FRONTAL ZONE. THERE APPEARS TO BE A TOUCH LESS CAPPING IN PROFILES...WHICH SHOULD PERMIT BETTER SCATTERED CONVECTIVE COVERAGE DURING THE AFTN/EVENING. WILL FEATURE A NORTH TO SOUTH GRADIENT IN POP WITH HIGH CHANCES OVER THE ELEVATED TERRAIN AND NORTH OF INTERSTATE 40 NEARER ANY POSSIBLE MCS TRACKS THROUGH WED EVENING. ANOTHER ROUND OF UPPER 90S TEMPS IS LIKELY WED AFTN ACROSS THE SE HALF...WITH WELL ABOVE CLIMO MAXES/MINS THROUGHOUT. HEIGHTS SHOULD GRADUALLY FALL THU THROUGH FRI ACROSS THE SOUTHEAST...BUT WITH THE REGION REMAINING IN THE WARM SECTOR AHEAD OF ANY COLD FRONTS APPROACHING FROM THE N OR NW. MAXES/MINS REMAIN 10 DEGREES ABOVE CLIMO THU BUT THEN SLOWLY MODERATING WHILE STAYING ABOVE NORMAL INTO THE WEEKEND. THERE REMAINS CONSIDERABLE SPREAD OVER THE DEVELOPMENT OF EASTERN TROUGHING BY NEXT WEEKEND. THE GFS SHOWS BROAD AND WEAK ERN TROUGHING WITH BETTER HEIGHT FALLS OVER THE NORTHERN PLAINS...WHILE THE ECMWF SHOWS MORE ROBUST EASTERN TROUGHING WITH A CLOSED SYSTEM OVER THE GREAT LAKES. THE GFS ENSEMBLE MEANS HAVE TRENDED MORE ECMWF LIKE RECENTLY AND THE FORECAST WILL LEAN IN THAT DIRECTION. TEMPS WILL REMAIN A CATEGORY ABOVE CLIMO THROUGH SATURDAY WITH CONVECTIVE COVERAGE PICKING UP AS A COLD FRONT APPROACHES/ARRIVES FROM THE NW. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AT KCLT AND ELSEWHERE...VFR CONDITIONS WILL PREVAIL THROUGH THE FCST PERIOD ASIDE FOR POSSIBLE TSRA/FOG ISSUES AT KAVL. WINDS WILL BE THE PRIMARY FCST CHALLENGE THROUGH THE AFTERNOON WITH FLOW INITIALIZING NW...HOWEVER EXPECTED TO BACK SW WITHIN AN HOUR OR SO. THUS...CROSS WIND ISSUES COULD ARISE AT KCLT OVER THE IMMEDIATE NEAR TERM. OTHERWISE...SW FLOW WILL PREVAIL UNDER FEW/SCT LOW VFR CU AND HIGH LEVEL CIRRUS. MODELS CONTINUE TO INDICATE MODEST DESTABILIZATION THIS AFTERNOON ACROSS THE HIGH TERRAIN THUS KAVL TAF FEATURES VCTS MENTION. FRONTAL AXIS TO THE NORTH IS PROGGED TO ADVANCE SOUTHWARD WITH HIGH RES GUIDANCE FAVORING AN MCS ADVECTING INTO THE HIGH TERRAIN LATE THIS EVENING. ALL SIGNS ARE POINTING TOWARD EROSION OF THIS BAND OF CONVECTION THEREFORE NO MENTION IN ANY TAF OTHER THAN SOME LOW/MID CLOUDS AT KAVL/KHKY. DEEP LAYER RIDGING WILL PREVAIL ON MONDAY WITH THE OLD FRONTAL BOUNDARY LIFTING BACK TO THE NORTH YIELDING RETURNING SOUTHERLY FLOW AND DIURNALLY INDUCED CU. OUTLOOK...PRECIPITATION CHANCES WILL REMAIN DIURNAL INTO THE WORK WEEK. AS A RESULT...THE GREATEST CHANCES FOR AFTERNOON SHRA/TSRA WILL BE ACROSS WESTERN NC WHERE THE LEAST SUBSIDENCE WILL RESIDE. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE... PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY. CONFIDENCE TABLE... 17-23Z 23-05Z 05-11Z 11-12Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 83% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...CDG/SBK SHORT TERM...HG LONG TERM...HG AVIATION...CDG CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1047 AM EDT SUN JUN 21 2015 .SYNOPSIS... DEEP HIGH PRESSURE WILL BUILD BACK ACROSS THE REGION TODAY AND REMAIN THROUGH THE MIDDLE OF THE WEEK. HOT TEMPERATURES WILL ALSO RETURN AS A STALLED FRONT REMAINS NORTH OF THE FORECAST AREA. BY THE END OF THE WORK WEEK...THE HOT PATTERN IS EXPECTED TO BREAK DOWN AS A TROUGH MOVES SOUTH OUT OF CANADA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 1030 AM EDT SUNDAY...LIGHT WNW FLOW CONTINUES TO PREVAIL UNDER MOSTLY SUNNY SKIES...WITH LOW CLOUDS STARTING TO BLOSSOM OVER THE SW MTNS. ASIDE FOR ISOLATED SHRA/TSRA OVER THE HIGH TERRAIN THIS AFTN...LATEST GUIDANCE CONTINUES TO FAVOR A FRONTAL ASSOCIATED MCS SLIDING ACROSS SOUTHEAST KY AND NORTHEAST TN THIS EVENING...HOWEVER WEAKENING AS IT APPROACHES/ENTERS WESTERN NC...THUS NO CHANGES TO POPS WERE NEEDED. OTHERWISE...TWEAKED TEMPERATURES/DEWPOINTS ALONG WITH SKY TO REFLECT MOST RECENT OBS/SAT AND LEFT THE REMAINDER OF THE FCST AS IS. PREVIOUS DISCUSSION... 430 AM EDT UPDATE...CURRENT NEAR TERM FCST IS IN GOOD SHAPE. MADE MINOR TWEAKS TO HR/LY TEMPS. ADDED AFTERNOON ISOL TSTMS ACROSS THE WRN UPSTATE AND NE GA BASED ON LATEST CAM AND RAP TRENDS TOWARD LESS CCL-LFC CIN LEVELS. THE LARGE SCALE PATTERN SHIFTS BACK INTO A MORE NORMAL SUMMERTIME CONFIG TODAY. SUBTROPICAL RIDGING WILL REASSERT ITSELF ACROSS THE SE CONUS CREATING A DIFFUSE WIND PROFILE ALOFT. CROSS SECTIONS SHOW DEEP NEGATIVE OMEGA OUTSIDE THE MTNS DURING THE AFTERNOON WITH LIMITED AVAILABLE LLVL MOISTURE. YET THE OP MODELS ARE MIXED WRT TO AMOUNT OF PARCEL DESTABILIZATION. THE NAM SHOWS A POTENTIAL OF THE SUBS INVERSION BEING BROKE AND ISOL EXPLOSIVE STORMS POSSIBLE OVER THE NON/MTNS. THE NAM ALSO HOLDS ONTO SOME MEASURE OF CIN ARND THE CCL THO. THE GFS ON THE OTHER HAND HAS UNBREAKABLE SBCIN AND NO POTENTIAL FOR SIGFNT CONVECTION. WENT WITH A BLEND OF THE RAW MODELS FOR POP WHICH KEEPS LESS THAN ISOL NON/MTNS ANS ISOL/SCT MTNS. THIS AGREES WELL WITH THE SREF OUTPUT AND THE LATEST CAMS...BUT FUTURE UPDATES COULD INTRODUCE ISOL CONVEC NON/MTNS. MAX TEMPS WILL REACH A FEW DEGREES WARMER THAN YESTERDAY...LIKELY M90S EAST AND U80S MTN VALLEYS. THE BEST AFTERNOON TD MIXING WILL OCCUR ACROSS THE ERN ZONES WHICH WILL KEEP MENTION OF HI/S OUT OF THE HWO. THE OVERNIGHT WILL FEATURE A QUICK REDUCTION OF DEBRIS CLOUDS AND STEEP SFC-BASED INVERSIONS. MTN VALLEYS...MAINLY THE FRENCH BROAD AND LITTLE TN...WILL ONCE AGAIN BE SUBJECT TO FG/BR ISSUES ARND DAYBREAK...ESP WHERE PRECIP FALLS THIS EVENING. EVEN WITH GOOD RAD COOLING THE ATMOS REMAINS RATHER STAGNANT WRT MIXING RATIOS...THUS MINS WILL REMAIN A COUPLE CATS ABOVE NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 245 AM EDT SUNDAY...A FLAT UPPER RIDGE WILL BUILD FROM THE SOUTHERN PLAINS TO THE SOUTHERN APPALACHIANS ON MONDAY. AN MCS ORIGINATING IN THE UPPER MIDWEST MAY PASS JUST N OF THE AREA MONDAY NIGHT. OTHERWISE...ISOLD CONVECTION SHOULD BE CONFINED IN AND NEAR THE MTNS IN LOW LEVEL WIND FIELD CONVERGENCE DURING THE DIURNALLY FAVORED AFTERNOON AND EVENING PERIODS. TEMPERATURES WILL INCREASE ONCE AGAIN UNDER THE BUILDING RIDGE WITH SOME HEAT INDEX VALUES REACHING 100 TO 105 IN THE SOUTHEAST HALF MON AFTN. STRONG UPPER HEIGHTS WILL REMAIN IN PLACE ON TUE AS THE BELT OF BETTER WESTERLIES STAYS JUST NORTH OF THE FORECAST AREA. 850 MB WINDS WILL TURN MORE WESTERLY AND A PIEDMONT SFC TROUGH SHOULD BECOME A BIT MORE PROMINENT. HOWEVER...MODEL PROFILES RETAIN QUITE A BIT OF CAPPING AND NEGATIVE AREA ALOFT SO CONVECTIVE COVERAGE WILL LIKELY BE MINIMIZED. WILL CONFINED ISOLD COVERAGE TO THE MTNS...BUT TSTMS WILL BE STRONG ANY PLACE THEY MANAGE TO FORM. MAX TEMPS WILL APPROACH 100 MAINLY ALONG/SOUTHEAST OF INTERSTATE 85. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 255 AM EDT SUNDAY...STRONG RIDGING CONTINUES ON WED BUT WITH A POSSIBLE MCS TRACK SETTING UP IN THE WNW FLOW FROM THE MIDWEST TO THE NC/VA LINE ALONG A STALLED FRONTAL ZONE. THERE APPEARS TO BE A TOUCH LESS CAPPING IN PROFILES...WHICH SHOULD PERMIT BETTER SCATTERED CONVECTIVE COVERAGE DURING THE AFTN/EVENING. WILL FEATURE A NORTH TO SOUTH GRADIENT IN POP WITH HIGH CHANCES OVER THE ELEVATED TERRAIN AND NORTH OF INTERSTATE 40 NEARER ANY POSSIBLE MCS TRACKS THROUGH WED EVENING. ANOTHER ROUND OF UPPER 90S TEMPS IS LIKELY WED AFTN ACROSS THE SE HALF...WITH WELL ABOVE CLIMO MAXES/MINS THROUGHOUT. HEIGHTS SHOULD GRADUALLY FALL THU THROUGH FRI ACROSS THE SOUTHEAST...BUT WITH THE REGION REMAINING IN THE WARM SECTOR AHEAD OF ANY COLD FRONTS APPROACHING FROM THE N OR NW. MAXES/MINS REMAIN 10 DEGREES ABOVE CLIMO THU BUT THEN SLOWLY MODERATING WHILE STAYING ABOVE NORMAL INTO THE WEEKEND. THERE REMAINS CONSIDERABLE SPREAD OVER THE DEVELOPMENT OF EASTERN TROUGHING BY NEXT WEEKEND. THE GFS SHOWS BROAD AND WEAK ERN TROUGHING WITH BETTER HEIGHT FALLS OVER THE NORTHERN PLAINS...WHILE THE ECMWF SHOWS MORE ROBUST EASTERN TROUGHING WITH A CLOSED SYSTEM OVER THE GREAT LAKES. THE GFS ENSEMBLE MEANS HAVE TRENDED MORE ECMWF LIKE RECENTLY AND THE FORECAST WILL LEAN IN THAT DIRECTION. TEMPS WILL REMAIN A CATEGORY ABOVE CLIMO THROUGH SATURDAY WITH CONVECTIVE COVERAGE PICKING UP AS A COLD FRONT APPROACHES/ARRIVES FROM THE NW. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... AT KCLT...NO FLIGHT RESTRICTIONS THRU THE PERIOD. BROAD ULVL RIDGING WILL RETURN TO THE SE CONUS AND GOOD SUBS WILL KEEP VERTICAL CLOUD DEVELOPMENT AT BAY. WINDS WILL REMAIN LIGHT THROUGH THE COLUMN WITH SFC WINDS 5-9 KTS ALIGNING S OF WEST DURING THE AFTERNOON. ELSEWHERE...DEEP HIGH PRESSURE WILL KEEP AFTERNOON CONVECTION LIMITED...MAINLY ISOL ACROSS THE NC/GA/SC MTNS WITH NO TAF MENTION NEEDED AT KAVL. RELATIVELY LIGHT WINDS WILL MAINTAIN UPVALLEY WINDS AT KAVL AND SW/LY TO W/LY ALL OTHER TERMINALS. OUTLOOK...PRECIPITATION CHANCES WILL REMAIN DIURNAL INTO THE WORK WEEK. AS A RESULT...THE GREATEST CHANCES FOR AFTERNOON SHRA/TSRA WILL BE ACROSS WESTERN NC WHERE THE LEAST SUBSIDENCE WILL RESIDE. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE... PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY. CONFIDENCE TABLE... 14-20Z 20-02Z 02-08Z 08-12Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% MED 74% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...CDG/SBK SHORT TERM...HG LONG TERM...HG AVIATION...SBK CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
631 AM EDT SUN JUN 21 2015 .SYNOPSIS... DEEP HIGH PRESSURE WILL BUILD BACK ACROSS THE REGION TODAY AND REMAIN THROUGH THE MIDDLE OF THE WEEK. HOT TEMPERATURES WILL ALSO RETURN AS A STALLED FRONT REMAINS NORTH OF THE FORECAST AREA. BY THE END OF THE WORK WEEK...THE HOT PATTERN IS EXPECTED TO BREAK DOWN AS A TROUGH MOVES SOUTH OUT OF CANADA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 630 AM EDT UPDATE...NO SIGFNT CHANGES NEED TO THE FCST. TEMPS AND TD/S TWEAKED SLIGHTLY...MAINLY ACROSS THE SRN UPSTATE WHERE HR/LYS WERE BUMPED UP A DEGREE OR TWO. 430 AM EDT UPDATE...CURRENT NEAR TERM FCST IS IN GOOD SHAPE. MADE MINOR TWEAKS TO HR/LY TEMPS. ADDED AFTERNOON ISOL TSTMS ACROSS THE WRN UPSTATE AND NE GA BASED ON LATEST CAM AND RAP TRENDS TOWARD LESS CCL-LFC CIN LEVELS. THE LARGE SCALE PATTERN SHIFTS BACK INTO A MORE NORMAL SUMMERTIME CONFIG TODAY. SUBTROPICAL RIDGING WILL REASSERT ITSELF ACROSS THE SE CONUS CREATING A DIFFUSE WIND PROFILE ALOFT. CROSS SECTIONS SHOW DEEP NEGATIVE OMEGA OUTSIDE THE MTNS DURING THE AFTERNOON WITH LIMITED AVAILABLE LLVL MOISTURE. YET THE OP MODELS ARE MIXED WRT TO AMOUNT OF PARCEL DESTABILIZATION. THE NAM SHOWS A POTENTIAL OF THE SUBS INVERSION BEING BROKE AND ISOL EXPLOSIVE STORMS POSSIBLE OVER THE NON/MTNS. THE NAM ALSO HOLDS ONTO SOME MEASURE OF CIN ARND THE CCL THO. THE GFS ON THE OTHER HAND HAS UNBREAKABLE SBCIN AND NO POTENTIAL FOR SIGFNT CONVECTION. WENT WITH A BLEND OF THE RAW MODELS FOR POP WHICH KEEPS LESS THAN ISOL NON/MTNS ANS ISOL/SCT MTNS. THIS AGREES WELL WITH THE SREF OUTPUT AND THE LATEST CAMS...BUT FUTURE UPDATES COULD INTRODUCE ISOL CONVEC NON/MTNS. MAX TEMPS WILL REACH A FEW DEGREES WARMER THAN YESTERDAY...LIKELY M90S EAST AND U80S MTN VALLEYS. THE BEST AFTERNOON TD MIXING WILL OCCUR ACROSS THE ERN ZONES WHICH WILL KEEP MENTION OF HI/S OUT OF THE HWO. THE OVERNIGHT WILL FEATURE A QUICK REDUCTION OF DEBRIS CLOUDS AND STEEP SFC-BASED INVERSIONS. MTN VALLEYS...MAINLY THE FRENCH BROAD AND LITTLE TN...WILL ONCE AGAIN BE SUBJECT TO FG/BR ISSUES ARND DAYBREAK...ESP WHERE PRECIP FALLS THIS EVENING. EVEN WITH GOOD RAD COOLING THE ATMOS REMAINS RATHER STAGNANT WRT MIXING RATIOS...THUS MINS WILL REMAIN A COUPLE CATS ABOVE NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 245 AM EDT SUNDAY...A FLAT UPPER RIDGE WILL BUILD FROM THE SOUTHERN PLAINS TO THE SOUTHERN APPALACHIANS ON MONDAY. AN MCS ORIGINATING IN THE UPPER MIDWEST MAY PASS JUST N OF THE AREA MONDAY NIGHT. OTHERWISE...ISOLD CONVECTION SHOULD BE CONFINED IN AND NEAR THE MTNS IN LOW LEVEL WIND FIELD CONVERGENCE DURING THE DIURNALLY FAVORED AFTERNOON AND EVENING PERIODS. TEMPERATURES WILL INCREASE ONCE AGAIN UNDER THE BUILDING RIDGE WITH SOME HEAT INDEX VALUES REACHING 100 TO 105 IN THE SOUTHEAST HALF MON AFTN. STRONG UPPER HEIGHTS WILL REMAIN IN PLACE ON TUE AS THE BELT OF BETTER WESTERLIES STAYS JUST NORTH OF THE FORECAST AREA. 850 MB WINDS WILL TURN MORE WESTERLY AND A PIEDMONT SFC TROUGH SHOULD BECOME A BIT MORE PROMINENT. HOWEVER...MODEL PROFILES RETAIN QUITE A BIT OF CAPPING AND NEGATIVE AREA ALOFT SO CONVECTIVE COVERAGE WILL LIKELY BE MINIMIZED. WILL CONFINED ISOLD COVERAGE TO THE MTNS...BUT TSTMS WILL BE STRONG ANY PLACE THEY MANAGE TO FORM. MAX TEMPS WILL APPROACH 100 MAINLY ALONG/SOUTHEAST OF INTERSTATE 85. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 255 AM EDT SUNDAY...STRONG RIDGING CONTINUES ON WED BUT WITH A POSSIBLE MCS TRACK SETTING UP IN THE WNW FLOW FROM THE MIDWEST TO THE NC/VA LINE ALONG A STALLED FRONTAL ZONE. THERE APPEARS TO BE A TOUCH LESS CAPPING IN PROFILES...WHICH SHOULD PERMIT BETTER SCATTERED CONVECTIVE COVERAGE DURING THE AFTN/EVENING. WILL FEATURE A NORTH TO SOUTH GRADIENT IN POP WITH HIGH CHANCES OVER THE ELEVATED TERRAIN AND NORTH OF INTERSTATE 40 NEARER ANY POSSIBLE MCS TRACKS THROUGH WED EVENING. ANOTHER ROUND OF UPPER 90S TEMPS IS LIKELY WED AFTN ACROSS THE SE HALF...WITH WELL ABOVE CLIMO MAXES/MINS THROUGHOUT. HEIGHTS SHOULD GRADUALLY FALL THU THROUGH FRI ACROSS THE SOUTHEAST...BUT WITH THE REGION REMAINING IN THE WARM SECTOR AHEAD OF ANY COLD FRONTS APPROACHING FROM THE N OR NW. MAXES/MINS REMAIN 10 DEGREES ABOVE CLIMO THU BUT THEN SLOWLY MODERATING WHILE STAYING ABOVE NORMAL INTO THE WEEKEND. THERE REMAINS CONSIDERABLE SPREAD OVER THE DEVELOPMENT OF EASTERN TROUGHING BY NEXT WEEKEND. THE GFS SHOWS BROAD AND WEAK ERN TROUGHING WITH BETTER HEIGHT FALLS OVER THE NORTHERN PLAINS...WHILE THE ECMWF SHOWS MORE ROBUST EASTERN TROUGHING WITH A CLOSED SYSTEM OVER THE GREAT LAKES. THE GFS ENSEMBLE MEANS HAVE TRENDED MORE ECMWF LIKE RECENTLY AND THE FORECAST WILL LEAN IN THAT DIRECTION. TEMPS WILL REMAIN A CATEGORY ABOVE CLIMO THROUGH SATURDAY WITH CONVECTIVE COVERAGE PICKING UP AS A COLD FRONT APPROACHES/ARRIVES FROM THE NW. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... AT KCLT...NO FLIGHT RESTRICTIONS THRU THE PERIOD. BROAD ULVL RIDGING WILL RETURN TO THE SE CONUS AND GOOD SUBS WILL KEEP VERTICAL CLOUD DEVELOPMENT AT BAY. WINDS WILL REMAIN LIGHT THROUGH THE COLUMN WITH SFC WINDS 5-9 KTS ALIGNING S OF WEST DURING THE AFTERNOON. ELSEWHERE...DEEP HIGH PRESSURE WILL KEEP AFTERNOON CONVECTION LIMITED...MAINLY ISOL ACROSS THE NC/GA/SC MTNS WITH NO TAF MENTION NEEDED AT KAVL. RELATIVELY LIGHT WINDS WILL MAINTAIN UPVALLEY WINDS AT KAVL AND SW/LY TO W/LY ALL OTHER TERMINALS. OUTLOOK...PRECIPITATION CHANCES WILL REMAIN DIURNAL INTO THE WORK WEEK. AS A RESULT...THE GREATEST CHANCES FOR AFTERNOON SHRA/TSRA WILL BE ACROSS WESTERN NC WHERE THE LEAST SUBSIDENCE WILL RESIDE. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE... PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY. CONFIDENCE TABLE... 10-16Z 16-22Z 22-04Z 04-06Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL MED 78% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...SBK SHORT TERM...HG LONG TERM...HG AVIATION...SBK CLIMATE...GSP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
451 AM EDT SUN JUN 21 2015 .SYNOPSIS... DEEP HIGH PRESSURE WILL BUILD BACK ACROSS THE REGION TODAY AND REMAIN THROUGH THE MIDDLE OF THE WEEK. HOT TEMPERATURES WILL ALSO RETURN AS A STALLED FRONT REMAINS NORTH OF THE FORECAST AREA. BY THE END OF THE WORK WEEK...THE HOT PATTERN IS EXPECTED TO BREAK DOWN AS A TROUGH MOVES SOUTH OUT OF CANADA. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 0430 AM EDT UPDATE...CURRENT NEAR TERM FCST IS IN GOOD SHAPE. MADE MINOR TWEAKS TO HR/LY TEMPS. ADDED AFTERNOON ISOL TSTMS ACROSS THE WRN UPSTATE AND NE GA BASED ON LATEST CAM AND RAP TRENDS TOWARD LESS CCL-LFC CIN LEVELS. THE LARGE SCALE PATTERN SHIFTS BACK INTO A MORE NORMAL SUMMERTIME CONFIG TODAY. SUBTROPICAL RIDGING WILL REASSERT ITSELF ACROSS THE SE CONUS CREATING A DIFFUSE WIND PROFILE ALOFT. CROSS SECTIONS SHOW DEEP NEGATIVE OMEGA OUTSIDE THE MTNS DURING THE AFTERNOON WITH LIMITED AVAILABLE LLVL MOISTURE. YET THE OP MODELS ARE MIXED WRT TO AMOUNT OF PARCEL DESTABILIZATION. THE NAM SHOWS A POTENTIAL OF THE SUBS INVERSION BEING BROKE AND ISOL EXPLOSIVE STORMS POSSIBLE OVER THE NON/MTNS. THE NAM ALSO HOLDS ONTO SOME MEASURE OF CIN ARND THE CCL THO. THE GFS ON THE OTHER HAND HAS UNBREAKABLE SBCIN AND NO POTENTIAL FOR SIGFNT CONVECTION. WENT WITH A BLEND OF THE RAW MODELS FOR POP WHICH KEEPS LESS THAN ISOL NON/MTNS ANS ISOL/SCT MTNS. THIS AGREES WELL WITH THE SREF OUTPUT AND THE LATEST CAMS...BUT FUTURE UPDATES COULD INTRODUCE ISOL CONVEC NON/MTNS. MAX TEMPS WILL REACH A FEW DEGREES WARMER THAN YESTERDAY...LIKELY M90S EAST AND U80S MTN VALLEYS. THE BEST AFTERNOON TD MIXING WILL OCCUR ACROSS THE ERN ZONES WHICH WILL KEEP MENTION OF HI/S OUT OF THE HWO. THE OVERNIGHT WILL FEATURE A QUICK REDUCTION OF DEBRIS CLOUDS AND STEEP SFC-BASED INVERSIONS. MTN VALLEYS...MAINLY THE FRENCH BROAD AND LITTLE TN...WILL ONCE AGAIN BE SUBJECT TO FG/BR ISSUES ARND DAYBREAK...ESP WHERE PRECIP FALLS THIS EVENING. EVEN WITH GOOD RAD COOLING THE ATMOS REMAINS RATHER STAGNANT WRT MIXING RATIOS...THUS MINS WILL REMAIN A COUPLE CATS ABOVE NORMAL. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... AS OF 245 AM EDT SUNDAY...A FLAT UPPER RIDGE WILL BUILD FROM THE SOUTHERN PLAINS TO THE SOUTHERN APPALACHIANS ON MONDAY. AN MCS ORIGINATING IN THE UPPER MIDWEST MAY PASS JUST N OF THE AREA MONDAY NIGHT. OTHERWISE...ISOLD CONVECTION SHOULD BE CONFINED IN AND NEAR THE MTNS IN LOW LEVEL WIND FIELD CONVERGENCE DURING THE DIURNALLY FAVORED AFTERNOON AND EVENING PERIODS. TEMPERATURES WILL INCREASE ONCE AGAIN UNDER THE BUILDING RIDGE WITH SOME HEAT INDEX VALUES REACHING 100 TO 105 IN THE SOUTHEAST HALF MON AFTN. STRONG UPPER HEIGHTS WILL REMAIN IN PLACE ON TUE AS THE BELT OF BETTER WESTERLIES STAYS JUST NORTH OF THE FORECAST AREA. 850 MB WINDS WILL TURN MORE WESTERLY AND A PIEDMONT SFC TROUGH SHOULD BECOME A BIT MORE PROMINENT. HOWEVER...MODEL PROFILES RETAIN QUITE A BIT OF CAPPING AND NEGATIVE AREA ALOFT SO CONVECTIVE COVERAGE WILL LIKELY BE MINIMIZED. WILL CONFINED ISOLD COVERAGE TO THE MTNS...BUT TSTMS WILL BE STRONG ANY PLACE THEY MANAGE TO FORM. MAX TEMPS WILL APPROACH 100 MAINLY ALONG/SOUTHEAST OF INTERSTATE 85. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 255 AM EDT SUNDAY...STRONG RIDGING CONTINUES ON WED BUT WITH A POSSIBLE MCS TRACK SETTING UP IN THE WNW FLOW FROM THE MIDWEST TO THE NC/VA LINE ALONG A STALLED FRONTAL ZONE. THERE APPEARS TO BE A TOUCH LESS CAPPING IN PROFILES...WHICH SHOULD PERMIT BETTER SCATTERED CONVECTIVE COVERAGE DURING THE AFTN/EVENING. WILL FEATURE A NORTH TO SOUTH GRADIENT IN POP WITH HIGH CHANCES OVER THE ELEVATED TERRAIN AND NORTH OF INTERSTATE 40 NEARER ANY POSSIBLE MCS TRACKS THROUGH WED EVENING. ANOTHER ROUND OF UPPER 90S TEMPS IS LIKELY WED AFTN ACROSS THE SE HALF...WITH WELL ABOVE CLIMO MAXES/MINS THROUGHOUT. HEIGHTS SHOULD GRADUALLY FALL THU THROUGH FRI ACROSS THE SOUTHEAST...BUT WITH THE REGION REMAINING IN THE WARM SECTOR AHEAD OF ANY COLD FRONTS APPROACHING FROM THE N OR NW. MAXES/MINS REMAIN 10 DEGREES ABOVE CLIMO THU BUT THEN SLOWLY MODERATING WHILE STAYING ABOVE NORMAL INTO THE WEEKEND. THERE REMAINS CONSIDERABLE SPREAD OVER THE DEVELOPMENT OF EASTERN TROUGHING BY NEXT WEEKEND. THE GFS SHOWS BROAD AND WEAK ERN TROUGHING WITH BETTER HEIGHT FALLS OVER THE NORTHERN PLAINS...WHILE THE ECMWF SHOWS MORE ROBUST EASTERN TROUGHING WITH A CLOSED SYSTEM OVER THE GREAT LAKES. THE GFS ENSEMBLE MEANS HAVE TRENDED MORE ECMWF LIKE RECENTLY AND THE FORECAST WILL LEAN IN THAT DIRECTION. TEMPS WILL REMAIN A CATEGORY ABOVE CLIMO THROUGH SATURDAY WITH CONVECTIVE COVERAGE PICKING UP AS A COLD FRONT APPROACHES/ARRIVES FROM THE NW. && .AVIATION /09Z SUNDAY THROUGH THURSDAY/... AT KCLT...NO FLIGHT RESTRICTIONS THRU THE PERIOD. BROAD ULVL RIDGING WILL RETURN TO THE SE CONUS AND GOOD SUBS WILL KEEP VERTICAL CLOUD DEVELOPMENT AT BAY. WINDS WILL REMAIN LIGHT THROUGH THE COLUMN WITH SFC WINDS 5-9 KTS ALIGNING S OF WEST DURING THE AFTERNOON. ELSEWHERE...ONLY RESTRICTIONS WILL BE MORNING FG/BR AT KAVL AND KHKY. SHUD BURN OFF QUICKLY AFT SUNRISE WITH GOOD SFC HEATING. DEEP HIGH PRESSURE WILL KEEP AFTERNOON CONVECTION LIMITED...MAINLY ISOL ACROSS THE NC/GA/SC MTNS WITH NO TAF MENTION NEEDED AT KAVL. RELATIVELY LIGHT WINDS WILL MAINTAIN UPVALLEY AT KAVL AND SW/LY TO W/LY ALL OTHER TERMINALS. OUTLOOK...PRECIPITATION CHANCES WILL REMAIN DIURNAL INTO THE WORK WEEK. AS A RESULT...THE GREATEST CHANCES FOR AFTERNOON SHRA/TSRA WILL BE ACROSS WESTERN NC WHERE THE LEAST SUBSIDENCE WILL RESIDE. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE... PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY. CONFIDENCE TABLE... 09-15Z 15-21Z 21-03Z 03-06Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 96% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR THIS WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...SBK NEAR TERM...SBK SHORT TERM...HG LONG TERM...HG AVIATION...SBK CLIMATE...GSP
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
131 AM EDT SUN JUN 21 2015 .SYNOPSIS... HIGH PRESSURE WILL STEADILY BUILD BACK INTO THE AREA FROM SUNDAY THROUGH THE MIDDLE OF NEXT WEEK...WITH HOT TEMPERATURES RETURNING AS A STALLED FRONT REMAINS NORTH OF THE REGION. BY THE END OF THE WORK WEEK THE HOT PATTERN IS EXPECTED TO BREAK DOWN AS A TROUGH MOVES SOUTHWARD OUT OF CANADA. && .NEAR TERM /THROUGH TODAY/... 0530 UTC UPDATE...NO SIGFNT CHANGES NEEDED TO THE FCST GRIDS. SKY AND POP WERE ADJ DOWN WHILE TEMPS AND TD/S WERE WITHIN THE DIURNAL FCST CURVE MOST LOCALES. 0200 UTC UPDATE...A LINE OF SHOWERS NORTH OF KCLT POPPED-UP IN THE LAST HOUR...BUT QUICKLY DISPERSED...LEAVING THE CWA NEARLY SHOWER-FREE. REMNANTS OF THESE SHOWERS...THEMSELVES RELATED TO THE OUTER RAIN BANDS OF THE REMNANTS OF TS BILL...ARE FORECAST TO GRADUALLY PROGRESS SOUTH EASTWARD BEFORE COMPLETELY DISSIPATING. REST OF UPDATES TO BLEND IN LATEST OBS FOR SKY AND TEMPERATURES. AS OF 720 PM...MOST SHOWERS AND ALL LIGHTNING HAS LEFT THE AREA WITH A FEW LIGHT SHOWERS REMAINING...MOSTLY OVER THE MOUNTAINS OF WESTERN NORTH CAROLINA. HRRR CONTINUES THE TREND OF DECLINING PRECIP SUNDAY MORNING. UPDATED FORECAST TO CLEAR MOST PRECIPITATION AND UPDATE WINDS AND TEMPERATURE TRENDS. FOR THE OVERNIGHT...THE SURFACE TROUGH ASSOCIATED WITH THE REMNANTS OF BILL WILL MOVE SOUTH OF THE AREA WITH WEAK HIGH PRESSURE BUILDING OVER THE AREA FROM THE WEST BY EARLY SUNDAY. LOOKS LIKE CONVECTIVE CHANCES ON SUNDAY WILL BE LIMITED BY OVERALL WEAK SUBSIDENCE AND LOW LEVEL CIN TO OVERCOME. HENCE...POPS WILL BE LIMITED TO ISOLATED IN NATURE OVER THE HIGH TERRAIN WHERE CIN MAY BE OVERCOME WITH AFTERNOON HEATING. WITH DOWNSLOPE FLOW...TEMPS SHOULD HAVE NO TROUBLE WARMING WELL INTO THE 90S EAST OF THE MOUNTAINS...WITH 80S MOUNTAIN VALLEYS. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... AS OF 200 PM EDT SATURDAY...THE SHORT RANGE FCST PERIOD INITIALIZES SUNDAY EVENING AMIDST BUILDING HEIGHTS ALOFT OVER THE DEEP SOUTH THANKS TO STRENGTHENING UPPER ANTICYCLONE. THE SURFACE PATTERN FEATURES AN ELONGATED/CLOSED LOW PRESSURE SYSTEM SLIDING ACROSS THE NORTHEAST CONUS...WHILE A TRAILING COLD FRONT STRETCHES ALONG THE OHIO VALLEY REGION NORTHWARD. CLOSER TO HOME...A TROF IN PLACE ACROSS THE ATLANTIC SEABOARD WILL WEAKEN INTO THE EVENING AS THE PARENT LOW PRESSURE SYSTEM MOVES AWAY. GUIDANCE SUGGESTS THAT THE AFORE MENTIONED FRONT COULD STALL JUST NORTH OF THE FORECAST AREA SUNDAY NIGHT...WITH THE NAM ACTUALLY PROVIDING HINTS OF AN ONGOING FRONTAL MCS MAKING A RUN AT THE NC MOUNTAINS. WITH UPPER HEIGHTS BEING LOWEST AND ABUNDANT INSTABILITY BEING PRESENT ACROSS THESE ZONES...CANNOT RULE OUT SUCH. EXPECTING ANY OF THIS ACTIVITY TO STRUGGLE AS IT SLIDES DEEPER INTO THE SUBSIDENCE LAYER BY EARLY MORNING MONDAY...IF IT SURVIVES A TRIP ACROSS THE MTNS IN THE FIRST PLACE. POPS WILL INITIALIZE AT SLIGHT CHANCE LEVELS OVER THE BLUE RIDGE BEFORE TAPERING INTO THE OVERNIGHT/MORNING. FROM THAT POINT ON GUIDANCE FAVORS INCREASED DEEP LAYER RIDGING THROUGH MIDWEEK WITH ANY SHRA/TSRA ACTIVITY BEING DIURNAL IN NATURE. OVERALL THE BEST PRECIPITATION CHANCES WILL BE ON MONDAY AFTERNOON WHERE SLIGHT/CHANCE MTN AND FOOTHILL POPS ARE FAVORED. SOUNDINGS ON TUESDAY GIVE MUCH SUPPORT TO THE RIDGE WITH MOST OF THE AREA STRUGGLING TO BREAK ANY CAPPING THAT IS IN PLACE...THUS TUESDAYS POPS FEATURE SLIGHT CHANCES OVER THE SW MTNS. WEAK FLOW ALOFT WILL LIMIT SHEAR THUS EXPECTING ANY CONVECTION EITHER DAY TO BE PULSE IN NATURE. TEMPERATURES THROUGH THE SHORT TERM PERIOD WILL ALSO BE OF NOTE AS ZONAL FLOW OVER THE NORTH COMBINES WITH THE AFORE MENTIONED UPPER RIDGE OVER THE SOUTH TO YIELD INCREASINGLY HOT/HUMID DAYS. HIGHS BOTH MONDAY AND TUESDAY ARE EXPECTED TO BE WELL ABOVE NORMAL WITH THE PIEDMONT APPROACHING/EXCEEDING THE CENTURY MARK...POTENTIALLY BREAKING RECORDS. EXPECTING HEAT INDEX VALUES TO APPROACH DANGEROUS LEVELS WITH HEAT ADVISORIES BEING A POSSIBILITY EACH DAY. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... AS OF 200 PM SAT...THE FLAT BUT STILL HOT UPPER RIDGE WILL REMAIN OVER THE SOUTHERN STATES THRU MIDWEEK...WHILE FASTER FLOW CONTINUES OVER THE RIDGE ACRS THE NERN CONUS. CONSENSUS OF THE LONG RANGE MODELS IS THAT AS A SHORTWAVE EMBEDDED IN THAT FLOW WILL LAY OUT A COLD FRONT ACRS THE OHIO VALLEY...WHICH STALLS TO OUR NORTH WED AS THE WAVE PULLS AWAY. LATEST AVBL DETERMINISTIC AND ENSEMBLE GUIDANCE HOWEVER DOES SHOW HEIGHTS BEGINNING TO FALL OVER OUR AREA THU AS A SHORTWAVE MOVES FROM THE CANADIAN PRAIRIE INTO THE GREAT LAKES REGION. THE PATTERN SUBSEQUENTLY BECOMES MORE AMPLIFIED...AND THAT FRONT IS EXPECTED TO FINALLY ARRIVE THU NIGHT. SOLUTIONS DIVERGE THEREAFTER BUT THERE ARE INDICATIONS WE WILL SEE ACTIVE WX GOING INTO NEXT WEEKEND AS A PRONOUNCED TROUGH DIGS INTO THE MISSISSIPPI VALLEY AND INTERACTS WITH THE EXISTING BOUNDARY. WE WILL CONTINUE TO FCST NEAR-RECORD MAXES WED AND THU...THOUGH THE FAVORED BLEND HAS TRENDED SLIGHTLY COOLER FROM THE LAST CYCLE...SO A HWO MENTION STILL IS UNWARRANTED. TEMPS WILL COOL A BIT FOR FRIDAY...BUT NOT RETURNING TO NEAR NORMAL UNTIL SATURDAY. CONVECTION IS POSSIBLE EACH DAY OF THE PERIOD. GFS PROFILES HAD PREVIOUSLY INDICATED POOR MIDLEVEL TEMPS WITHIN THE RIDGE WOULD KEEP MUCH OF THE PIEDMONT CAPPED WED AND THU AFTNS...BUT THE LATEST RUN SEEMS TO REFLECT A WEAKER RIDGE AND SUGGESTS FREE CONVECTION THERE. WEAK SHEAR PROFILES AND MODEST INSTABILITY MEAN PULSE STORMS WILL PROBABLY BE OF SOME CONCERN ON THESE DAYS. WEAK DOWNSLOPING WILL LIKELY LIMIT THE COVERAGE HOWEVER. TO SUMMARIZE...ON WED-THU POPS PEAK AT A HIGH CHC MTNS AND SCHC TO LOW CHC PIEDMONT. THE FRONT WARRANTS POPS PERSISTING OVERNIGHT THU NIGHT WITH MOST OF THE CWFA SOLIDLY IN CHC RANGE THRU EARLY SUNDAY ON ACCOUNT OF THE AFOREMENTIONED SYNOPTIC FEATURES. SHEAR PARAMETERS WAX LATE IN THE PERIOD BUT ARE NOT CURRENTLY INDICATIVE OF A SIGNIFICANT SEVERE THREAT. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... AT KCLT...NO FLIGHT RESTRICTIONS THRU THE PERIOD. BROAD ULVL RIDGING WILL RETURN TO THE SE CONUS AND GOOD SUBS WILL KEEP VERTICAL CLOUD DEVELOPMENT AT BAY. WINDS WILL REMAIN LIGHT THROUGH THE COLUMN WITH SFC WINDS 5-9 KTS ALIGNING S OF WEST DURING THE AFTERNOON. ELSEWHERE...ONLY RESTRICTIONS WILL BE MORNING FG/BR AT KAVL AND KHKY. SHUD BURN OFF QUICKLY AFT SUNRISE WITH GOOD SFC HEATING. DEEP HIGH PRESSURE WILL KEEP AFTERNOON CONVECTION LIMITED...MAINLY ISOL ACROSS THE NC/GA/SC MTNS WITH NO TAF MENTION NEEDED AT KAVL. RELATIVELY LIGHT WINDS WILL MAINTAIN UPVALLEY AT KAVL AND SW/LY TO W/LY ALL OTHER TERMINALS. OUTLOOK...PRECIPITATION CHANCES WILL REMAIN DIURNAL INTO THE WORK WEEK. AS A RESULT...THE GREATEST CHANCES FOR AFTERNOON SHRA/TSRA WILL BE ACROSS WESTERN NC WHERE THE LEAST SUBSIDENCE WILL RESIDE. MORNING RESTRICTIONS DUE TO FOG AND/OR STRATUS ARE POSSIBLE... PARTICULARLY WHERE HEAVY RAIN FELL THE PREVIOUS DAY. CONFIDENCE TABLE... 05-11Z 11-17Z 17-23Z 23-00Z KCLT HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGSP HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAVL HIGH 100% HIGH 100% HIGH 100% HIGH 100% KHKY HIGH 100% HIGH 100% HIGH 100% HIGH 100% KGMU HIGH 100% HIGH 100% HIGH 100% HIGH 100% KAND HIGH 100% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR NEXT WEEK...WITH YEARS IN WHICH THE VALUES WERE LAST REACHED. MONDAY JUNE 22... AVL 94 1964 CLT 98 1956 GSP 99 2006 TUESDAY JUNE 23... AVL 93 1988 CLT 98 1988 GSP 99 1988 WEDNESDAY JUNE 24... AVL 94 1952 CLT 102 1930 GSP 100 1952 THURSDAY JUNE 25... AVL 96 1952 CLT 102 1914 GSP 101 1952 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...NONE. SC...NONE. && $$ SYNOPSIS...WIMBERLEY NEAR TERM...LG/SBK/WJM SHORT TERM...CDG LONG TERM...WIMBERLEY AVIATION...SBK CLIMATE...DEO/WIMBERLEY
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
715 PM CDT MON JUN 22 2015 .UPDATE...EVENING UPDATE. UPDATED TO REMOVE TH HEAT ADVISORY THIS AFTERNOON. MORE HEAT IS IN STORE FOR TOMORROW...ALTHOUGH CLOUDS AND HAZE HAS PREVENTED TEMPERATURES FROM CLIMBING AS HIGH AS THEY COULD HAVE. FORECAST LOOKS TO BE IN GOOD SHAPE. NO MORE RAIN IS EXPECTED TONIGHT WITH LOWS IN THE MIDDLE 70S. && .PREV DISCUSSION... /ISSUED 605 PM CDT MON JUN 22 2015/ UPDATE... UPDATED TO ADD 00Z AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 318 PM CDT MON JUN 22 2015/ DISCUSSION... CURRENTLY...A STRONG UPPER RIDGE CONTINUES TO BUILD EAST FROM THE SOUTHERN PLAINS. MOISTURE HAS POOLED ACROSS THE MIDSOUTH TODAY WITH PRECIP H20 VALUES APPROACHING 2 INCHES AND SURFACE DEWPOINTS IN THE MID 70S. THIS DEEPER MOISTURE COMBINED WITH A WEAK DISTURBANCE MOVING AROUND THE WESTERN EDGE OF THE UPPER RIDGE HAS TOUCHED OFF AN AREA OF THUNDERSTORMS ACROSS PARTS OF WEST TENNESSEE AND NORTHEAST MISSISSIPPI. THE HRRR DID AN EXCELLENT JOB WITH COMPLEX. TO THE WEST OF THE THUNDERSTORMS THE HEAT AND HUMIDITY IS BUILDING. HEAT INDEX VALUES HAVE REACHED 105 AT JONESBORO AND WEST MEMPHIS. TONIGHT...THUNDERSTORMS ACROSS EASTERN SECTIONS WILL PUSH EAST AND DISSIPATE BY EARLY THIS EVENING LEAVING BEHIND MOSTLY CLEAR SKIES. TEMPS WILL BE MILD WITH LOWS IN THE 70S. TUESDAY THROUGH THURSDAY...THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD OVER THE AREA ON TUESDAY. BY WEDNESDAY IT WILL BE CENTERED DIRECTLY OVER THE AREA THEN START TO GRADUALLY WEAKEN ON THURSDAY. THIS WILL BE A HOT AND HUMID PERIOD. THOUGH ISOLATED SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT TUESDAY AND WEDNESDAY COVERAGE SHOULD BE MINIMAL. HIGHS ON TUESDAY WILL PUSH INTO THE MID 90S WHICH WHEN COMBINED WITH HIGH HUMIDITY WILL CREATE HEAT INDEX VALUES GREATER THAN 105 ACROSS MUCH OF THE MS DELTA INCLUDING THE MEMPHIS METRO AREA. A HEAT ADVISORY CONTINUES THROUGH 7 PM TUESDAY FOR THE AFOREMENTIONED AREA. BY WEDNESDAY TEMPS MAY HIT THE UPPER 90S IN A FEW SPOTS AND THE HEAT ADVISORY WILL PROBABLY NEED TO BE EXPANDED. BY THURSDAY THE UPPER RIDGE WEAKENS SLIGHTLY AND SOME DEEPER MOISTURE MOVES IN FROM THE SOUTH WHICH WILL RESULT IN BETTER SHOWER/THUNDERSTORM COVERAGE...ESPECIALLY ACROSS NORTH MISSISSIPPI. IT WILL STILL BE QUITE HOT WITH HIGHS IN THE MID 90S IN SOME PLACES SO HEAT ADVISORIES MAY BE NEEDED ON THURSDAY AS WELL. FRIDAY INTO THE WEEKEND...MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT WITH BREAKING DOWN THE UPPER RIDGE AS A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S. A COLD FRONT WILL PUSH THROUGH THE MIDSOUTH FRIDAY AND SATURDAY WITH NUMEROUS SHOWERS AND THUNDERSTORMS. RAIN CHANCES WILL DIMINISH LATER SATURDAY AND SUNDAY. MUCH COOLER AIR WILL PUSH INTO THE AREA FOR THE WEEKEND WITH HIGHS IN THE 80S AND LOWS IN THE 60S. SJM && .AVIATION... 00Z TAF CYCLE VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE PERIOD. WINDS WILL DIMINISH TO 5 KTS OR LESS TONIGHT AND INCREASE TO 8-11 KTS AFTER 23/15Z. CJC && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR CRAIGHEAD- CRITTENDEN-CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR COAHOMA-DESOTO- PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR SHELBY-TIPTON. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
605 PM CDT MON JUN 22 2015 .UPDATE... UPDATED TO ADD 00Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 318 PM CDT MON JUN 22 2015/ DISCUSSION... CURRENTLY...A STRONG UPPER RIDGE CONTINUES TO BUILD EAST FROM THE SOUTHERN PLAINS. MOISTURE HAS POOLED ACROSS THE MIDSOUTH TODAY WITH PRECIP H20 VALUES APPROACHING 2 INCHES AND SURFACE DEWPOINTS IN THE MID 70S. THIS DEEPER MOISTURE COMBINED WITH A WEAK DISTURBANCE MOVING AROUND THE WESTERN EDGE OF THE UPPER RIDGE HAS TOUCHED OFF AN AREA OF THUNDERSTORMS ACROSS PARTS OF WEST TENNESSEE AND NORTHEAST MISSISSIPPI. THE HRRR DID AN EXCELLENT JOB WITH COMPLEX. TO THE WEST OF THE THUNDERSTORMS THE HEAT AND HUMIDITY IS BUILDING. HEAT INDEX VALUES HAVE REACHED 105 AT JONESBORO AND WEST MEMPHIS. TONIGHT...THUNDERSTORMS ACROSS EASTERN SECTIONS WILL PUSH EAST AND DISSIPATE BY EARLY THIS EVENING LEAVING BEHIND MOSTLY CLEAR SKIES. TEMPS WILL BE MILD WITH LOWS IN THE 70S. TUESDAY THROUGH THURSDAY...THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD OVER THE AREA ON TUESDAY. BY WEDNESDAY IT WILL BE CENTERED DIRECTLY OVER THE AREA THEN START TO GRADUALLY WEAKEN ON THURSDAY. THIS WILL BE A HOT AND HUMID PERIOD. THOUGH ISOLATED SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT TUESDAY AND WEDNESDAY COVERAGE SHOULD BE MINIMAL. HIGHS ON TUESDAY WILL PUSH INTO THE MID 90S WHICH WHEN COMBINED WITH HIGH HUMIDITY WILL CREATE HEAT INDEX VALUES GREATER THAN 105 ACROSS MUCH OF THE MS DELTA INCLUDING THE MEMPHIS METRO AREA. A HEAT ADVISORY CONTINUES THROUGH 7 PM TUESDAY FOR THE AFOREMENTIONED AREA. BY WEDNESDAY TEMPS MAY HIT THE UPPER 90S IN A FEW SPOTS AND THE HEAT ADVISORY WILL PROBABLY NEED TO BE EXPANDED. BY THURSDAY THE UPPER RIDGE WEAKENS SLIGHTLY AND SOME DEEPER MOISTURE MOVES IN FROM THE SOUTH WHICH WILL RESULT IN BETTER SHOWER/THUNDERSTORM COVERAGE...ESPECIALLY ACROSS NORTH MISSISSIPPI. IT WILL STILL BE QUITE HOT WITH HIGHS IN THE MID 90S IN SOME PLACES SO HEAT ADVISORIES MAY BE NEEDED ON THURSDAY AS WELL. FRIDAY INTO THE WEEKEND...MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT WITH BREAKING DOWN THE UPPER RIDGE AS A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S. A COLD FRONT WILL PUSH THROUGH THE MIDSOUTH FRIDAY AND SATURDAY WITH NUMEROUS SHOWERS AND THUNDERSTORMS. RAIN CHANCES WILL DIMINISH LATER SATURDAY AND SUNDAY. MUCH COOLER AIR WILL PUSH INTO THE AREA FOR THE WEEKEND WITH HIGHS IN THE 80S AND LOWS IN THE 60S. SJM && .AVIATION... 00Z TAF CYCLE VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE PERIOD. WINDS WILL DIMINISH TO 5 KTS OR LESS TONIGHT AND INCREASE TO 8-11 KTS AFTER 23/15Z. CJC && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR CRAIGHEAD-CRITTENDEN- CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR COAHOMA-DESOTO-PANOLA- QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY UNTIL 7 PM CDT TUESDAY FOR SHELBY-TIPTON. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
256 PM CDT SUN JUN 21 2015 .DISCUSSION... LATEST RADAR IMAGERY SHOWS A LINE OF STRONG THUNDERSTORMS DEVELOPING TO OUR NORTH ACROSS SOUTHERN KENTUCKY ALONG A SOUTHWARD MOVING OUTFLOW BOUNDARY. THIS ACTIVITY APPEARS LIKELY TO SKIRT ACROSS NORTHEAST ZONES LATE THIS AFTERNOON AND EVENING PER HRRR MODEL RUNS...AND HAVE BUMPED UP POPS FURTHER FOR THAT AREA. CANNOT RULE OUT A STRONG OR POSSIBLY SEVERE STORM WITH DAMAGING WINDS OR HAIL DUE TO THE VERY UNSTABLE AIRMASS IN PLACE...BUT BIGGER THREAT WILL REMAIN TO OUR NORTH AND EAST IN CURRENT WATCH AREA. OTHER CONVECTION IS DEVELOPING TO OUR WEST ACROSS THE MEG AREA...AND THIS ACTIVITY MAY DEVELOP INTO THE REST OF THE MID STATE AS WELL. ANY SHOWERS AND STORMS ARE EXPECTED TO DIMINISH THIS EVENING WITH LOSS OF DAYTIME HEATING. 12Z GFS/ECMWF SHOW UPPER RIDGE CURRENTLY OVER THE SOUTHWEST CONUS WILL SHIFT EASTWARD MONDAY THROUGH WEDNESDAY AND BECOME CENTERED OVER THE TENNESSEE VALLEY. THIS WILL LEAD TO INCREASINGLY HOT TEMPS WITH HIGHS RISING INTO THE MID TO UPPER 90S WEST OF THE PLATEAU. WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S...HEAT INDEX READINGS WILL RISE INTO THE 100-105 DEGREE RANGE EACH AFTERNOON AND BE CLOSE TO HEAT ADVISORY CRITERIA...ESPECIALLY ON WEDNESDAY WHEN 500MB HEIGHTS INCREASE TO AROUND 596 DM. BY THURSDAY...GLOBAL MODELS INDICATE RIDGE WILL SHIFT EASTWARD AND NORTHWEST FLOW WILL DEVELOP...BRINGING A MUCH HIGHER CHANCE FOR RAIN ALONG WITH COOLER TEMPERATURES FOR THE END OF THE WEEK INTO THE WEEKEND. HAVE CONTINUED TREND OF GRADUALLY LOWERING TEMPERATURES WHILE INCREASING POPS THROUGH THE END OF THE FORECAST PERIOD. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 73 95 75 97 / 10 0 0 10 CLARKSVILLE 73 93 74 95 / 10 0 0 10 CROSSVILLE 69 89 71 90 / 20 10 10 10 COLUMBIA 72 95 74 97 / 10 0 0 10 LAWRENCEBURG 72 94 73 96 / 10 0 10 10 WAVERLY 73 94 74 95 / 10 0 0 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHAMBURGER
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
135 PM CDT SUN JUN 21 2015 .AVIATION UPDATE... VFR CONDITIONS EXPECTED TO RULE THIS CYCLE...WITH A FEW CAVEATS. VCNTY STORMS COULD AFFECT BNA/CSV LATE THIS AFTERNOON/EVENING. MVFR EARLY MORNING FOG MAY DEVELOP ALL SITES BUT ESPECIALLY CSV. WINDS COULD GUST TO 15 TO 25 THIS AFTERNOON BNA/CKV. && .PREV DISCUSSION... /ISSUED 940 AM CDT SUN JUN 21 2015/ UPDATE... LATEST SURFACE OBS SHOW A VERY WARM HUMID MORNING ACROSS THE MID STATE WITH TEMPS ALREADY IN THE UPPER 70S TO MID 80S AND DEWPOINTS IN THE 70S. DESPITE SOME CLOUD COVER...HIGHS IN THE UPPER 80S TO MID 90S STILL APPEAR REASONABLE WITH HEAT INDEX VALUES RISING OVER 100 THIS AFTERNOON. VISIBLE SATELLITE SHOWS CONSIDERABLE CUMULUS DEVELOPMENT ONGOING...AND WITH AMPLE LOW LEVEL MOISTURE AND SOME LIFT DUE TO A SHORTWAVE PASSING TO OUR NORTH...CONCERNED A FEW SHOWERS OR STORMS MAY DEVELOP OR SPREAD OUT OF KY LATER TODAY INTO THE KY BORDER COUNTIES AND UPPER CUMBERLAND REGION. SOME OF THE LATEST HRRR AND NAM RUNS IN FACT DO SHOW SOME CONVECTION SPREADING ACROSS NORTHEAST ZONES OUT OF KY LATER TODAY. THUS WILL ADD A SLIGHT CHANCE POP TO FAR NORTHERN AND EASTERN ZONES FOR THIS AFTERNOON/EVENING. REST OF FORECAST IS GENERALLY ON TRACK WITH UPDATED PRODUCTS OUT. SHAMBURGER PREV DISCUSSION... /ISSUED 624 AM CDT SUN JUN 21 2015/ UPDATE...FOR 12Z AVIATION. AVIATION...12Z TAF DISCUSSION. VFR CONDITIONS EXPECTED FOR MOST OF THIS TAF PERIOD WITH SOME MID AND HIGH LEVEL CLOUDS TO START OUT. SOME MVFR IVS IS LIKELY TO CONTINUE AT KCSV FOR ANOTHER HOUR OR SO. WINDS WILL BE BREEZY THIS AFTERNOON WITH SW GUSTS TO 15-17 KTS. UNGER PREV DISCUSSION... /ISSUED 333 AM CDT SUN JUN 21 2015/ DISCUSSION... WITH TODAY BEING THE FIRST DAY OF SUMMER...MIDDLE TENNESSEE SURE KNOWS HOW TO START OUT WITH A BANG...HELLO HEAT! A WARM AND MUGGY NIGHT CONTINUES ACROSS MIDDLE TENNESSEE THIS EARLY MORNING AS BLOW OFF CIRRUS FROM A COMPLEX OF THUNDERSTORMS ACROSS THE OHIO VALLEY INVADES THE AREA. THIS CLOUD COVER WILL DO LITTLE TO LIMIT HIGHS TODAY AS PLENTY OF SUNSHINE AND HUMID CONDITIONS WILL EXIST. HIGHS SHOULD HAVE NO PROBLEM REACHING THE LOW TO MID 90S AREA WIDE WITH HEAT INDEX VALUES CLOSING IN ON 100F DEGREES. LOWS TONIGHT WILL ONLY DROP INTO THE LOW TO MID 70S. MONDAY THROUGH WEDNESDAY...HEAT WILL BE THE MAIN WEATHER STORY AS HIGHS WILL BE IN THE MID TO UPPER 90S AND HEAT INDEX READINGS SURPASS THE TRIPLE DIGIT MARK. TUESDAY AND WEDNESDAY LOOK TO BE THE MOST BRUTAL CONDITIONS AS FAR AS HEAT IS CONCERNED...AND WOULD NOT BE SURPRISED IF A HEAT ADVISORY IS NEEDED FOR BOTH DAYS. FOR NOW...WILL COVER THE HEAT WITH A SPECIAL WEATHER STATEMENT CONCERNING THIS TIME FRAME AS TODAY AND MONDAY WILL NOT QUITE HIT HEAT ADVISORY CRITERIA. THE UPPER RIDGE RESPONSIBLE FOR THIS HEAT WAVE WILL FINALLY BREAK DOWN ALLOWING NORTHWEST FLOW TO INVADE THE AREA EVER SO SLIGHTLY. AS A RESULT...THE PATTERN OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL RETURN THURSDAY AND CONTINUE THROUGH NEXT WEEKEND. SEVERAL UPPER LEVEL IMPULSES WILL MOVE OVER THE FORECAST AREA DURING THIS TIME ENHANCING THE CHANCES FOR PRECIPITATION. BETTER CHANCES FOR STORMS WILL OCCUR CLOSER TO THE WEEKEND. REGARDLESS...WITH THE EXTRA CLOUD COVER AND CONVECTION AROUND...HIGHS WILL NOT BE QUITE AS UNBEARABLE...WITH MOST LOCATIONS IN THE LOW 90S. NOTICE I SAID QUITE AS UNBEARABLE SINCE NORMAL HIGHS FOR THIS TIME OF YEAR ARE TYPICALLY BETWEEN 85-87F. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 73 95 75 97 / 10 0 0 10 CLARKSVILLE 73 93 74 94 / 10 0 0 10 CROSSVILLE 69 89 71 90 / 20 10 10 10 COLUMBIA 72 95 74 97 / 10 0 0 10 LAWRENCEBURG 72 94 73 96 / 10 0 10 10 WAVERLY 73 94 74 95 / 10 0 0 10 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 07
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1219 PM CDT SUN JUN 21 2015 .DISCUSSION... UPDATED FOR 18Z AVIATION DISCUSSION && .PREV DISCUSSION... /ISSUED 1048 AM CDT SUN JUN 21 2015/ UPDATE... TEMPERATURES ARE RISING QUICKLY AROUND THE MIDSOUTH THIS MORNING. CURRENT READINGS RANGE FROM 82-87 DEGREES. HIGHS WILL REACH INTO THE LOWER TO MID 90S THIS AFTERNOON. THE COMBINATION OF THE HOT TEMPERATURES AND HUMIDITY...WILL PRODUCE HEAT INDICES AROUND 105 DEGREES FROM MEMPHIS SOUTHWESTWARD. IN ADDITION...CAN/T RULE OUT A FEW THUNDERSTORMS POPPING UP THIS AFTERNOON. WILL ADD 20 POPS ACROSS THE ENTIRE AREA. SOME STORMS COULD BE STRONG TO SEVERE WITH DAMAGING WINDS BEING THE MAIN THREAT. KRM DISCUSSION... /ISSUED 437 AM CDT SUN JUN 21 2015/ EXCESSIVE HEAT IS THE MAIN PROBLEM OF CONCERN IN THIS FORECAST. SOUTHWEST WINDS AND HIGH DEW POINTS WERE HOLDING TEMPERATURES UP INTO THE 70S THIS MORNING WITH LOCATIONS IN AND AROUND MEMPHIS STRUGGLING TO DROP TO BELOW 80 DEGREES. SKIES WERE MOSTLY CLEAR TO PARTLY CLOUDY WITH RAIN FREE CONDITIONS. THE HRRR IS NOT SHOWING MUCH IN THE WAY OF ANY SHOWERS OR THUNDERSTORMS TODAY...THUS CONTINUED TO KEEP POPS BELOW MENTIONABLE LEVELS ALTHOUGH COULD BE A STRAY SHOWER / THUNDERSTORM. SOUTHWEST WINDS WILL CONTINUE TO PUSH HOT AIR INTO THE REGION WITH HIGHS A DEGREE OR SO HOTTER THAN YESTERDAY. WENT AHEAD AND ISSUED A HEAT ADVISORY BEGINNING THIS AFTERNOON FOR SOUTHWEST TN INCLUDING THE CITY OF MEMPHIS...EAST CENTRAL AR...AND NORTHWEST MS. IT LOOKS TO BE A BORDERLINE SITUATION THIS AFTERNOON WITH HEAT INDEX READINGS NEAR OR JUST SHY OF THE 105 DEGREE MARK...BUT PREFERRED TO ERR ON THE SIDE OF CAUTION AND THUS ISSUED THE ADVISORY. BIGGEST QUESTIONS ARE IF HIGH LEVEL CLOUDS APPROACHING FROM THE WEST WILL HAVE MUCH AFFECT ON HIGH TEMPERATURES...AND HOW MUCH SURFACE DEW POINTS WILL MIX OUT THIS AFTERNOON FROM DRIER AIR ALOFT. YESTERDAY...SURFACE DEW POINTS DID NOT MIX OUT VERY MUCH. FOR HIGH TEMPERATURES...LEANED TOWARD THE NAM / MET GUIDANCE WHICH DID A GOOD JOB FORECASTING THE HIGHS YESTERDAY. THE MIDSOUTH WILL BE SANDWICHED TODAY BETWEEN A STRONG HOT UPPER LEVEL HIGH PRESSURE SYSTEM CENTERED OVER THE SOUTHWESTERN UNITED STATES AND HIGH PRESSURE ALOFT CENTERED OFF THE ATLANTIC COAST. SOME HIGH LEVEL CLOUDS WILL OCCUR TODAY AND TONIGHT IN A WEAKNESS BETWEEN THE TWO HIGH PRESSURE SYSTEMS ESPECIALLY FROM EAST CENTRAL AR INTO NORTH MS. MONDAY AND TUESDAY...THE STRONG UPPER LEVEL RIDGE OVER THE SOUTHWESTERN UNITED STATES WILL EXPAND EASTWARD AND INCLUDE THE MIDSOUTH. THIS WILL LEAD TO VERY HOT CONDITIONS EXPANDING OVER THE MIDSOUTH WITH LITTLE IF ANY RAIN. H5 HEIGHTS ARE FORECAST BY THE GFS TO INCREASE TO NEAR 597 DM TUESDAY. CONTINUED THE HEAT ADVISORY MONDAY FOR PORTIONS OF SOUTHWEST TN...EAST CENTRAL AR AND NORTHWEST MS. THE HEAT ADVISORY MAY NEED TO BE EXPANDED IN LATER FORECASTS TO INCLUDE MORE OF THE MIDSOUTH FOR MONDAY. IN ADDITION...AS THE HEAT EXPANDS TUESDAY A HEAT ADVISORY MAY BECOMING NECESSARY FOR MUCH OF THE MIDSOUTH. WEDNESDAY...THE HEAT WILL CONTINUE WITH A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS. SOME MOISTURE IS FORECAST TO INCREASE FROM THE SOUTH. TOWARD THE END OF THE WORK WEEK..THE UPPER LEVEL RIDGE IS FORECAST TO BREAK DOWN ACROSS THE MIDSOUTH WITH THE REGION MOVING INTO NORTHWEST FLOW ALOFT. THIS WILL LEAD TO INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS ALONG WITH A DECREASE IN HIGH TEMPERATURES. WILL ALSO NEED TO WATCH FOR DEVELOPMENT OF MESOSCALE CONVECTIVE SYSTEMS UPSTREAM AS WE EVOLVE INTO NORTHWEST FLOW ALOFT...BUT THIS IS DIFFICULT TO PINPOINT AT THIS TIME. THE ECMWF AND GFS DIFFER ON THE POSSIBLE PASSAGE OF A COLD FRONT OVER THE WEEKEND. JCL && .AVIATION... 18Z TAFS VFR CONDITIONS ARE EXPECTED THROUGH THE PERIOD. W/SW WINDS AT 10-12 KTS THIS AFTN WITH SOME HIGHER GUSTS AT KJBR. WINDS WILL DIMINISH THIS EVENING THEN INCREASE BACK TO 10 KTS BY 22/15Z. SJM && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR CRITTENDEN-CROSS-LEE AR- PHILLIPS-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR COAHOMA-DESOTO-PANOLA- QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR SHELBY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1048 AM CDT SUN JUN 21 2015 .UPDATE... TEMPERATURES ARE RISING QUICKLY AROUND THE MIDSOUTH THIS MORNING. CURRENT READINGS RANGE FROM 82-87 DEGREES. HIGHS WILL REACH INTO THE LOWER TO MID 90S THIS AFTERNOON. THE COMBINATION OF THE HOT TEMPERATURES AND HUMIDITY...WILL PRODUCE HEAT INDICES AROUND 105 DEGREES FROM MEMPHIS SOUTHWESTWARD. IN ADDITION...CAN/T RULE OUT A FEW THUNDERSTORMS POPPING UP THIS AFTERNOON. WILL ADD 20 POPS ACROSS THE ENTIRE AREA. SOME STORMS COULD BE STRONG TO SEVERE WITH DAMAGING WINDS BEING THE MAIN THREAT. KRM && .DISCUSSION... /ISSUED 437 AM CDT SUN JUN 21 2015/ EXCESSIVE HEAT IS THE MAIN PROBLEM OF CONCERN IN THIS FORECAST. SOUTHWEST WINDS AND HIGH DEW POINTS WERE HOLDING TEMPERATURES UP INTO THE 70S THIS MORNING WITH LOCATIONS IN AND AROUND MEMPHIS STRUGGLING TO DROP TO BELOW 80 DEGREES. SKIES WERE MOSTLY CLEAR TO PARTLY CLOUDY WITH RAIN FREE CONDITIONS. THE HRRR IS NOT SHOWING MUCH IN THE WAY OF ANY SHOWERS OR THUNDERSTORMS TODAY...THUS CONTINUED TO KEEP POPS BELOW MENTIONABLE LEVELS ALTHOUGH COULD BE A STRAY SHOWER / THUNDERSTORM. SOUTHWEST WINDS WILL CONTINUE TO PUSH HOT AIR INTO THE REGION WITH HIGHS A DEGREE OR SO HOTTER THAN YESTERDAY. WENT AHEAD AND ISSUED A HEAT ADVISORY BEGINNING THIS AFTERNOON FOR SOUTHWEST TN INCLUDING THE CITY OF MEMPHIS...EAST CENTRAL AR...AND NORTHWEST MS. IT LOOKS TO BE A BORDERLINE SITUATION THIS AFTERNOON WITH HEAT INDEX READINGS NEAR OR JUST SHY OF THE 105 DEGREE MARK...BUT PREFERRED TO ERR ON THE SIDE OF CAUTION AND THUS ISSUED THE ADVISORY. BIGGEST QUESTIONS ARE IF HIGH LEVEL CLOUDS APPROACHING FROM THE WEST WILL HAVE MUCH AFFECT ON HIGH TEMPERATURES...AND HOW MUCH SURFACE DEW POINTS WILL MIX OUT THIS AFTERNOON FROM DRIER AIR ALOFT. YESTERDAY...SURFACE DEW POINTS DID NOT MIX OUT VERY MUCH. FOR HIGH TEMPERATURES...LEANED TOWARD THE NAM / MET GUIDANCE WHICH DID A GOOD JOB FORECASTING THE HIGHS YESTERDAY. THE MIDSOUTH WILL BE SANDWICHED TODAY BETWEEN A STRONG HOT UPPER LEVEL HIGH PRESSURE SYSTEM CENTERED OVER THE SOUTHWESTERN UNITED STATES AND HIGH PRESSURE ALOFT CENTERED OFF THE ATLANTIC COAST. SOME HIGH LEVEL CLOUDS WILL OCCUR TODAY AND TONIGHT IN A WEAKNESS BETWEEN THE TWO HIGH PRESSURE SYSTEMS ESPECIALLY FROM EAST CENTRAL AR INTO NORTH MS. MONDAY AND TUESDAY...THE STRONG UPPER LEVEL RIDGE OVER THE SOUTHWESTERN UNITED STATES WILL EXPAND EASTWARD AND INCLUDE THE MIDSOUTH. THIS WILL LEAD TO VERY HOT CONDITIONS EXPANDING OVER THE MIDSOUTH WITH LITTLE IF ANY RAIN. H5 HEIGHTS ARE FORECAST BY THE GFS TO INCREASE TO NEAR 597 DM TUESDAY. CONTINUED THE HEAT ADVISORY MONDAY FOR PORTIONS OF SOUTHWEST TN...EAST CENTRAL AR AND NORTHWEST MS. THE HEAT ADVISORY MAY NEED TO BE EXPANDED IN LATER FORECASTS TO INCLUDE MORE OF THE MIDSOUTH FOR MONDAY. IN ADDITION...AS THE HEAT EXPANDS TUESDAY A HEAT ADVISORY MAY BECOMING NECESSARY FOR MUCH OF THE MIDSOUTH. WEDNESDAY...THE HEAT WILL CONTINUE WITH A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS. SOME MOISTURE IS FORECAST TO INCREASE FROM THE SOUTH. TOWARD THE END OF THE WORK WEEK..THE UPPER LEVEL RIDGE IS FORECAST TO BREAK DOWN ACROSS THE MIDSOUTH WITH THE REGION MOVING INTO NORTHWEST FLOW ALOFT. THIS WILL LEAD TO INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS ALONG WITH A DECREASE IN HIGH TEMPERATURES. WILL ALSO NEED TO WATCH FOR DEVELOPMENT OF MESOSCALE CONVECTIVE SYSTEMS UPSTREAM AS WE EVOLVE INTO NORTHWEST FLOW ALOFT...BUT THIS IS DIFFICULT TO PINPOINT AT THIS TIME. THE ECMWF AND GFS DIFFER ON THE POSSIBLE PASSAGE OF A COLD FRONT OVER THE WEEKEND. JCL && .AVIATION... 12Z TAFS VFR CONDITIONS ARE EXPECTED THROUGH THE TAF VALID PERIOD. WINDS WILL FAVOR SOUTHWESTERLY NEAR 10 KTS DURING THE DAY...DECREASING TO AROUND 5 KTS AFTER 00Z MONDAY. TVT && && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR CRITTENDEN-CROSS-LEE AR- PHILLIPS-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR COAHOMA-DESOTO-PANOLA- QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY UNTIL 7 PM CDT MONDAY FOR SHELBY. && $$
AREA FORECAST DISCUSSION
NWS NASHVILLE TN
940 AM CDT SUN JUN 21 2015 .UPDATE... LATEST SURFACE OBS SHOW A VERY WARM HUMID MORNING ACROSS THE MID STATE WITH TEMPS ALREADY IN THE UPPER 70S TO MID 80S AND DEWPOINTS IN THE 70S. DESPITE SOME CLOUD COVER...HIGHS IN THE UPPER 80S TO MID 90S STILL APPEAR REASONABLE WITH HEAT INDEX VALUES RISING OVER 100 THIS AFTERNOON. VISIBLE SATELLITE SHOWS CONSIDERABLE CUMULUS DEVELOPMENT ONGOING...AND WITH AMPLE LOW LEVEL MOISTURE AND SOME LIFT DUE TO A SHORTWAVE PASSING TO OUR NORTH...CONCERNED A FEW SHOWERS OR STORMS MAY DEVELOP OR SPREAD OUT OF KY LATER TODAY INTO THE KY BORDER COUNTIES AND UPPER CUMBERLAND REGION. SOME OF THE LATEST HRRR AND NAM RUNS IN FACT DO SHOW SOME CONVECTION SPREADING ACROSS NORTHEAST ZONES OUT OF KY LATER TODAY. THUS WILL ADD A SLIGHT CHANCE POP TO FAR NORTHERN AND EASTERN ZONES FOR THIS AFTERNOON/EVENING. REST OF FORECAST IS GENERALLY ON TRACK WITH UPDATED PRODUCTS OUT. SHAMBURGER && .PREV DISCUSSION... /ISSUED 624 AM CDT SUN JUN 21 2015/ UPDATE...FOR 12Z AVIATION. AVIATION...12Z TAF DISCUSSION. VFR CONDITIONS EXPECTED FOR MOST OF THIS TAF PERIOD WITH SOME MID AND HIGH LEVEL CLOUDS TO START OUT. SOME MVFR IVS IS LIKELY TO CONTINUE AT KCSV FOR ANOTHER HOUR OR SO. WINDS WILL BE BREEZY THIS AFTERNOON WITH SW GUSTS TO 15-17 KTS. UNGER PREV DISCUSSION... /ISSUED 333 AM CDT SUN JUN 21 2015/ DISCUSSION... WITH TODAY BEING THE FIRST DAY OF SUMMER...MIDDLE TENNESSEE SURE KNOWS HOW TO START OUT WITH A BANG...HELLO HEAT! A WARM AND MUGGY NIGHT CONTINUES ACROSS MIDDLE TENNESSEE THIS EARLY MORNING AS BLOW OFF CIRRUS FROM A COMPLEX OF THUNDERSTORMS ACROSS THE OHIO VALLEY INVADES THE AREA. THIS CLOUD COVER WILL DO LITTLE TO LIMIT HIGHS TODAY AS PLENTY OF SUNSHINE AND HUMID CONDITIONS WILL EXIST. HIGHS SHOULD HAVE NO PROBLEM REACHING THE LOW TO MID 90S AREA WIDE WITH HEAT INDEX VALUES CLOSING IN ON 100F DEGREES. LOWS TONIGHT WILL ONLY DROP INTO THE LOW TO MID 70S. MONDAY THROUGH WEDNESDAY...HEAT WILL BE THE MAIN WEATHER STORY AS HIGHS WILL BE IN THE MID TO UPPER 90S AND HEAT INDEX READINGS SURPASS THE TRIPLE DIGIT MARK. TUESDAY AND WEDNESDAY LOOK TO BE THE MOST BRUTAL CONDITIONS AS FAR AS HEAT IS CONCERNED...AND WOULD NOT BE SURPRISED IF A HEAT ADVISORY IS NEEDED FOR BOTH DAYS. FOR NOW...WILL COVER THE HEAT WITH A SPECIAL WEATHER STATEMENT CONCERNING THIS TIME FRAME AS TODAY AND MONDAY WILL NOT QUITE HIT HEAT ADVISORY CRITERIA. THE UPPER RIDGE RESPONSIBLE FOR THIS HEAT WAVE WILL FINALLY BREAK DOWN ALLOWING NORTHWEST FLOW TO INVADE THE AREA EVER SO SLIGHTLY. AS A RESULT...THE PATTERN OF AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS WILL RETURN THURSDAY AND CONTINUE THROUGH NEXT WEEKEND. SEVERAL UPPER LEVEL IMPULSES WILL MOVE OVER THE FORECAST AREA DURING THIS TIME ENHANCING THE CHANCES FOR PRECIPITATION. BETTER CHANCES FOR STORMS WILL OCCUR CLOSER TO THE WEEKEND. REGARDLESS...WITH THE EXTRA CLOUD COVER AND CONVECTION AROUND...HIGHS WILL NOT BE QUITE AS UNBEARABLE...WITH MOST LOCATIONS IN THE LOW 90S. NOTICE I SAID QUITE AS UNBEARABLE SINCE NORMAL HIGHS FOR THIS TIME OF YEAR ARE TYPICALLY BETWEEN 85-87F. && .PRELIMINARY POINT TEMPS/POPS... NASHVILLE 94 73 95 74 / 10 10 10 0 CLARKSVILLE 92 73 93 74 / 20 10 10 0 CROSSVILLE 88 70 88 71 / 20 20 10 10 COLUMBIA 94 73 95 74 / 10 10 10 10 LAWRENCEBURG 93 73 94 73 / 10 0 10 10 WAVERLY 93 74 94 74 / 10 0 10 0 && .OHX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 55
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
614 AM CDT SUN JUN 21 2015 .UPDATE... UPDATED AVIATION DISCUSSION FOR 12Z TAFS... && .PREV DISCUSSION... /ISSUED 437 AM CDT SUN JUN 21 2015/ DISCUSSION... EXCESSIVE HEAT IS THE MAIN PROBLEM OF CONCERN IN THIS FORECAST. SOUTHWEST WINDS AND HIGH DEW POINTS WERE HOLDING TEMPERATURES UP INTO THE 70S THIS MORNING WITH LOCATIONS IN AND AROUND MEMPHIS STRUGGLING TO DROP TO BELOW 80 DEGREES. SKIES WERE MOSTLY CLEAR TO PARTLY CLOUDY WITH RAIN FREE CONDITIONS. THE HRRR IS NOT SHOWING MUCH IN THE WAY OF ANY SHOWERS OR THUNDERSTORMS TODAY...THUS CONTINUED TO KEEP POPS BELOW MENTIONABLE LEVELS ALTHOUGH COULD BE A STRAY SHOWER / THUNDERSTORM. SOUTHWEST WINDS WILL CONTINUE TO PUSH HOT AIR INTO THE REGION WITH HIGHS A DEGREE OR SO HOTTER THAN YESTERDAY. WENT AHEAD AND ISSUED A HEAT ADVISORY BEGINNING THIS AFTERNOON FOR SOUTHWEST TN INCLUDING THE CITY OF MEMPHIS...EAST CENTRAL AR...AND NORTHWEST MS. IT LOOKS TO BE A BORDERLINE SITUATION THIS AFTERNOON WITH HEAT INDEX READINGS NEAR OR JUST SHY OF THE 105 DEGREE MARK...BUT PREFERRED TO ERR ON THE SIDE OF CAUTION AND THUS ISSUED THE ADVISORY. BIGGEST QUESTIONS ARE IF HIGH LEVEL CLOUDS APPROACHING FROM THE WEST WILL HAVE MUCH AFFECT ON HIGH TEMPERATURES...AND HOW MUCH SURFACE DEW POINTS WILL MIX OUT THIS AFTERNOON FROM DRIER AIR ALOFT. YESTERDAY...SURFACE DEW POINTS DID NOT MIX OUT VERY MUCH. FOR HIGH TEMPERATURES...LEANED TOWARD THE NAM / MET GUIDANCE WHICH DID A GOOD JOB FORECASTING THE HIGHS YESTERDAY. THE MIDSOUTH WILL BE SANDWICHED TODAY BETWEEN A STRONG HOT UPPER LEVEL HIGH PRESSURE SYSTEM CENTERED OVER THE SOUTHWESTERN UNITED STATES AND HIGH PRESSURE ALOFT CENTERED OFF THE ATLANTIC COAST. SOME HIGH LEVEL CLOUDS WILL OCCUR TODAY AND TONIGHT IN A WEAKNESS BETWEEN THE TWO HIGH PRESSURE SYSTEMS ESPECIALLY FROM EAST CENTRAL AR INTO NORTH MS. MONDAY AND TUESDAY...THE STRONG UPPER LEVEL RIDGE OVER THE SOUTHWESTERN UNITED STATES WILL EXPAND EASTWARD AND INCLUDE THE MIDSOUTH. THIS WILL LEAD TO VERY HOT CONDITIONS EXPANDING OVER THE MIDSOUTH WITH LITTLE IF ANY RAIN. H5 HEIGHTS ARE FORECAST BY THE GFS TO INCREASE TO NEAR 597 DM TUESDAY. CONTINUED THE HEAT ADVISORY MONDAY FOR PORTIONS OF SOUTHWEST TN...EAST CENTRAL AR AND NORTHWEST MS. THE HEAT ADVISORY MAY NEED TO BE EXPANDED IN LATER FORECASTS TO INCLUDE MORE OF THE MIDSOUTH FOR MONDAY. IN ADDITION...AS THE HEAT EXPANDS TUESDAY A HEAT ADVISORY MAY BECOMING NECESSARY FOR MUCH OF THE MIDSOUTH. WEDNESDAY...THE HEAT WILL CONTINUE WITH A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS. SOME MOISTURE IS FORECAST TO INCREASE FROM THE SOUTH. TOWARD THE END OF THE WORK WEEK..THE UPPER LEVEL RIDGE IS FORECAST TO BREAK DOWN ACROSS THE MIDSOUTH WITH THE REGION MOVING INTO NORTHWEST FLOW ALOFT. THIS WILL LEAD TO INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS ALONG WITH A DECREASE IN HIGH TEMPERATURES. WILL ALSO NEED TO WATCH FOR DEVELOPMENT OF MESOSCALE CONVECTIVE SYSTEMS UPSTREAM AS WE EVOLVE INTO NORTHWEST FLOW ALOFT...BUT THIS IS DIFFICULT TO PINPOINT AT THIS TIME. THE ECMWF AND GFS DIFFER ON THE POSSIBLE PASSAGE OF A COLD FRONT OVER THE WEEKEND. JCL .AVIATION... 12Z TAFS VFR CONDITIONS ARE EXPECTED THROUGH THE TAF VALID PERIOD. WINDS WILL FAVOR SOUTHWESTERLY NEAR 10 KTS DURING THE DAY...DECREASING TO AROUND 5 KTS AFTER 00Z MONDAY. TVT && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR CRITTENDEN-CROSS-LEE AR-PHILLIPS-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR COAHOMA-DESOTO-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR SHELBY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
437 AM CDT SUN JUN 21 2015 .DISCUSSION... EXCESSIVE HEAT IS THE MAIN PROBLEM OF CONCERN IN THIS FORECAST. SOUTHWEST WINDS AND HIGH DEW POINTS WERE HOLDING TEMPERATURES UP INTO THE 70S THIS MORNING WITH LOCATIONS IN AND AROUND MEMPHIS STRUGGLING TO DROP TO BELOW 80 DEGREES. SKIES WERE MOSTLY CLEAR TO PARTLY CLOUDY WITH RAIN FREE CONDITIONS. THE HRRR IS NOT SHOWING MUCH IN THE WAY OF ANY SHOWERS OR THUNDERSTORMS TODAY...THUS CONTINUED TO KEEP POPS BELOW MENTIONABLE LEVELS ALTHOUGH COULD BE A STRAY SHOWER / THUNDERSTORM. SOUTHWEST WINDS WILL CONTINUE TO PUSH HOT AIR INTO THE REGION WITH HIGHS A DEGREE OR SO HOTTER THAN YESTERDAY. WENT AHEAD AND ISSUED A HEAT ADVISORY BEGINNING THIS AFTERNOON FOR SOUTHWEST TN INCLUDING THE CITY OF MEMPHIS...EAST CENTRAL AR...AND NORTHWEST MS. IT LOOKS TO BE A BORDERLINE SITUATION THIS AFTERNOON WITH HEAT INDEX READINGS NEAR OR JUST SHY OF THE 105 DEGREE MARK...BUT PREFERRED TO ERR ON THE SIDE OF CAUTION AND THUS ISSUED THE ADVISORY. BIGGEST QUESTIONS ARE IF HIGH LEVEL CLOUDS APPROACHING FROM THE WEST WILL HAVE MUCH AFFECT ON HIGH TEMPERATURES...AND HOW MUCH SURFACE DEW POINTS WILL MIX OUT THIS AFTERNOON FROM DRIER AIR ALOFT. YESTERDAY...SURFACE DEW POINTS DID NOT MIX OUT VERY MUCH. FOR HIGH TEMPERATURES...LEANED TOWARD THE NAM / MET GUIDANCE WHICH DID A GOOD JOB FORECASTING THE HIGHS YESTERDAY. THE MIDSOUTH WILL BE SANDWICHED TODAY BETWEEN A STRONG HOT UPPER LEVEL HIGH PRESSURE SYSTEM CENTERED OVER THE SOUTHWESTERN UNITED STATES AND HIGH PRESSURE ALOFT CENTERED OFF THE ATLANTIC COAST. SOME HIGH LEVEL CLOUDS WILL OCCUR TODAY AND TONIGHT IN A WEAKNESS BETWEEN THE TWO HIGH PRESSURE SYSTEMS ESPECIALLY FROM EAST CENTRAL AR INTO NORTH MS. MONDAY AND TUESDAY...THE STRONG UPPER LEVEL RIDGE OVER THE SOUTHWESTERN UNITED STATES WILL EXPAND EASTWARD AND INCLUDE THE MIDSOUTH. THIS WILL LEAD TO VERY HOT CONDITIONS EXPANDING OVER THE MIDSOUTH WITH LITTLE IF ANY RAIN. H5 HEIGHTS ARE FORECAST BY THE GFS TO INCREASE TO NEAR 597 DM TUESDAY. CONTINUED THE HEAT ADVISORY MONDAY FOR PORTIONS OF SOUTHWEST TN...EAST CENTRAL AR AND NORTHWEST MS. THE HEAT ADVISORY MAY NEED TO BE EXPANDED IN LATER FORECASTS TO INCLUDE MORE OF THE MIDSOUTH FOR MONDAY. IN ADDITION...AS THE HEAT EXPANDS TUESDAY A HEAT ADVISORY MAY BECOMING NECESSARY FOR MUCH OF THE MIDSOUTH. WEDNESDAY...THE HEAT WILL CONTINUE WITH A SMALL CHANCE OF SHOWERS AND THUNDERSTORMS. SOME MOISTURE IS FORECAST TO INCREASE FROM THE SOUTH. TOWARD THE END OF THE WORK WEEK..THE UPPER LEVEL RIDGE IS FORECAST TO BREAK DOWN ACROSS THE MIDSOUTH WITH THE REGION MOVING INTO NORTHWEST FLOW ALOFT. THIS WILL LEAD TO INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS ALONG WITH A DECREASE IN HIGH TEMPERATURES. WILL ALSO NEED TO WATCH FOR DEVELOPMENT OF MESOSCALE CONVECTIVE SYSTEMS UPSTREAM AS WE EVOLVE INTO NORTHWEST FLOW ALOFT...BUT THIS IS DIFFICULT TO PINPOINT AT THIS TIME. THE ECMWF AND GFS DIFFER ON THE POSSIBLE PASSAGE OF A COLD FRONT OVER THE WEEKEND. JCL && .AVIATION... 06Z TAFS VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. WINDS WILL BE S-SW BETWEEN 5-10 KT. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR CRITTENDEN-CROSS-LEE AR-PHILLIPS-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR COAHOMA-DESOTO-PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM CDT MONDAY FOR SHELBY. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1115 PM CDT SAT JUN 20 2015 .UPDATE...AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 905 PM CDT SAT JUN 20 2015/ DISCUSSION...WATER VAPOR SATELLITE TRENDS/00Z UPPER AIR ANALYSIS INDICATES AN UPPER LEVEL RIDGE PRESENT OVER THE LOWER MISSISSIPPI VALLEY WHILE A MESOSCALE CONVECTIVE SYSTEM /MCS/ HAS DEVELOPED OVER SOUTHEAST IOWA/NORTHEAST MISSOURI. ISOLATED SHOWERS AND THUNDERSTORMS OVER THE PAST COUPLE OF HOURS HAVE DIMINISHED WITH THE LOSS OF DAYTIME INSTABILITY AND THE ONLY REMNANTS IS AN ISOLATED RAIN SHOWER OVER SOUTHERN HAYWOOD AND MADISON COUNTIES IN TENNESSEE. LATEST HRRR AND 00Z WRF INDICATE ANY ADDITIONAL SHOWER/THUNDERSTORM POTENTIAL WILL REMAIN MINIMAL AT BEST. WILL MAKE SOME MINOR ADJUSTMENTS TO FORECAST TO ACCOUNT FOR LATEST TRENDS. OTHERWISE...FORECAST OVERALL IS IN GREAT SHAPE. UPDATED GRIDS WILL BE AVAILABLE SHORTLY. CJC PREV DISCUSSION... /ISSUED 616 PM CDT SAT JUN 20 2015/ UPDATE...AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 252 PM CDT SAT JUN 20 2015/ DISCUSSION... HEAT AND HUMIDITY WILL DOMINATE THE FIRST HALF OF THE FORECAST PERIOD AS AN UPPER RIDGE OF HIGH PRESSURE GRADUALLY BUILDS INTO THE AREA OVER THE NEXT COUPLE OF DAYS. CURRENTLY...DIURNAL SHOWERS AND THUNDERSTORMS ARE POPPING UP ACROSS PORTIONS OF EASTERN ARKANSAS AND NORTHWEST MISSISSIPPI. TEMPERATURES HAVE WARMED INTO THE UPPER 80S TO LOWER 90S THUS FAR TODAY. CURRENT HEAT INDEX READING IN MEMPHIS IS AROUND 101-102 DEGREES. THE DIURNAL CONVECTION SHOULD DIE OFF AROUND 7 PM. CIRRUS CURRENTLY OVER TEXAS WILL SPREAD OVER THE CWA THIS SHOULD KEEP LOW TEMPERATURES UP COMPARED TO LAST NIGHT. READINGS WILL BE IN THE MID TO UPPER 70S. EXPECT CONDITIONS TO BE WARMER ON SUNDAY THUS HEAT INDICES COULD REACH 105 DEGREES IN A FEW LOCATIONS. A HEAT ADVISORY MAY BECOME NECESSARY. THE HEAT WILL BUILD DURING THE EARLY TO MIDDLE PART OF NEXT WEEK AS THE RIDGE MOVES INTO THE AREA. MODELS ARE WAVERING ON HOW STRONG THE RIDGE WILL BE THUS ISOLATED DIURNAL CONVECTION COULD OCCUR ON ABOUT EACH DAY BUT NOT ENOUGH AGREEMENT AMONG MODELS TO PUT ANY MENTION IN FORECAST YET. BY WEDNESDAY...BETTER AGREEMENT OCCURS THUS HAVE ADDED IN MENTION OF SHOWERS AND THUNDERSTORMS. HIGHS WILL GENERALLY BE IN THE MID TO UPPER 90S. HEAT INDICES SHOULD HIT AROUND 105 DEGREES EACH DAY. BY THURSDAY...THE UPPER RIDGE BEGINS TO BREAK DOWN. CHANCES FOR SHOWERS AND THUNDERSTORMS WILL INCREASE FROM THURSDAY INTO EARLY NEXT WEEKEND AS A COLD FRONT MOVES INTO THE AREA. TEMPERATURES WILL RETURN TO NORMAL DURING THIS TIME PERIOD DUE TO CLOUD COVER AND CONVECTION. KRM && .AVIATION...06Z TAFS VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. WINDS WILL BE S-SW BETWEEN 5-10 KT. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
652 PM CDT MON JUN 22 2015 .AVIATION... ALONG THE RIO GRANDE...BAND OF SHRA/ISOLD TSRA WILL PERSIST FOR THE NEXT FEW HOURS WITH ADDITIONAL SHRA/TSRA POSSIBLE OVERNIGHT INTO TUESDAY AS UPPER LEVEL TROUGH LINGERS OVER MEXICO AND HAVE VCSH FOR KDRT THROUGH THE FORECAST. ELSEWHERE...ISOLD SHRA/TSRA ARE POSSIBLE THIS EVENING THROUGH TUESDAY WITH VCSH MENTIONED AT KAUS/KSAT/KSSF ONLY FOR TUESDAY AFTERNOON DUE BEST FORCING WITH DAYTIME HEATING. VFR SKIES EARLY THIS EVENING WILL LOWER TO MVFR CIGS AS STRATUS DEVELOPS. CIGS WILL LOWER TO IFR/LIFR AS BR AND IFR/MVFR VSBYS DEVELOP OVERNIGHT. CIGS RISE AS BR DISSIPATES TUESDAY MORNING AND THEN VFR IN THE AFTERNOON. S TO SE WINDS 4 TO 11 KTS WILL PREVAIL. GUSTS TO 40 KTS ARE POSSIBLE DUE TO OUTFLOWS FROM SHRA/TSRA. && .PREV DISCUSSION... /ISSUED 217 PM CDT MON JUN 22 2015/ SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)... THERE IS NOT MUCH RAIN ACTIVITY ONGOING ACROSS SOUTH-CENTRAL TEXAS THIS AFTERNOON. THERE IS ONE AREA OF LIGHT TO MODERATE RAIN REMAINING ACROSS THE EXTREME SOUTHWESTERN COUNTIES...BUT THE REST OF THE CWA REMAINS MOSTLY DRY. PRECIPITABLE WATER VALUES CONTINUE TO SLOWLY DECREASE AS A 700 MB RIDGE AXIS BUILDS INTO SOUTHEAST TEXAS FROM THE EAST. SUBSIDENCE FROM THIS SYSTEM AND SLIGHTLY DRIER AIR IS KEEPING THE COVERAGE OF ACTIVITY MUCH LESS THAN PREVIOUS DAYS. THE HRRR IS STILL FORECASTING SOME ISOLATED CONVECTION LATER THIS AFTERNOON AND WILL KEEP 20 POPS IN THE FORECAST FOR THE EVENING FOR MUCH OF THE AREA. AN UPPER LOW REMAINS JUST WEST OF THE CWA AND WILL HAVE 30 POPS THIS EVENING CLOSER TO THE RIO GRANDE TO ACCOUNT FOR BETTER LIFT IN THIS PART OF THE CWA. FOR TOMORROW...THE 700 MB RIDGE AXIS WILL REMAIN TO OUR EAST WITH THE UPPER LOW TO OUR WEST WEAKENING AND BEGINNING TO SHIFT WEST. MOISTURE VALUES WILL BE HIGH ENOUGH TO WARRANT 20 POPS FOR MUCH OF THE CWA FOR ANY CONVECTION THAT DEVELOPS IN THE WEAK SOUTHEAST FLOW. TEMPERATURES TOMORROW AFTERNOON WILL ONLY REACH THE UPPER 80S TO NEAR 90 DEGREES. HOWEVER...DEWPOINTS ARE NOT EXPECTED TO MIX OUT AND WILL REMAIN IN THE LOWER 70S. HEAT INDICES TOMORROW AFTERNOON MAY BE AS HIGH AS THE UPPER 90S. LONG TERM (WEDNESDAY THROUGH MONDAY)... WEDNESDAY/THURSDAY WILL BE A SIMILAR SETUP TO TUESDAY...BUT OUR WESTERN UPPER LOW WILL BE A NON-PLAYER WEATHER WISE. THE GULF OF MEXICO WILL REMAIN OPENED UP WITH SOUTHEAST FLOW AND AFTERNOON CONVECTION WILL REMAIN POSSIBLE MAINLY ACROSS THE SOUTHERN AND SOUTHEASTERN COUNTIES. THE UPPER RIDGE WILL STRENGTHEN OVER THE AREA FRIDAY AND THE REGION SHOULD REMAIN MOSTLY DRY. BY LATE SATURDAY AND INTO SUNDAY...THE UPPER PATTERN WILL BE SHIFTING. A STRONG RIDGE WILL AMPLIFY ACROSS THE WESTERN CONUS WITH A DEEP TROUGH OVER THE EASTERN CONUS. THIS PLACES THE CENTRAL PLAINS IN NORTHWEST FLOW BETWEEN THE SYSTEMS. MODELS ARE SHOWING A WEAK FRONTAL BOUNDARY NEARING THE CWA SATURDAY NIGHT AND SUNDAY AND WILL INCREASE POPS TO ACCOUNT FOR THIS FEATURE. WILL HAVE TO WATCH FOR POSSIBLE LOCALLY HEAVY RAINFALL GIVEN THERE WILL BE A BOUNDARY PRESENT AND DECENT MOISTURE. IT IS TOO EARLY TO GET INTO SPECIFICS BECAUSE OF MANY UNKNOWNS ON THE MESOSCALE BUT IT IS SOMETHING TO WATCH. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 73 90 73 90 74 / 10 20 10 20 10 AUSTIN BERGSTROM INTL AIRPORT 72 90 72 90 73 / 10 20 10 20 10 NEW BRAUNFELS MUNI AIRPORT 73 89 73 89 74 / 20 20 10 20 10 BURNET MUNI AIRPORT 72 89 72 88 73 / 10 10 10 10 10 DEL RIO INTL AIRPORT 73 89 74 89 75 / 30 20 20 20 10 GEORGETOWN MUNI AIRPORT 72 89 73 89 74 / 10 10 10 10 10 HONDO MUNI AIRPORT 73 88 73 88 74 / 20 20 10 20 10 SAN MARCOS MUNI AIRPORT 73 89 73 89 74 / 10 20 10 20 10 LA GRANGE - FAYETTE REGIONAL 74 90 74 89 75 / - 20 10 30 10 SAN ANTONIO INTL AIRPORT 74 89 74 88 75 / 20 20 10 20 10 STINSON MUNI AIRPORT 75 89 74 89 75 / 20 20 10 20 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...04 SYNOPTIC/GRIDS...OAKS PUBLIC SERVICE/DATA COLLECTION...LH
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
321 PM CDT SUN JUN 21 2015 .DISCUSSION... SO FAR THIS AFTERNOON...ONLY A COUPLE CELLS HAVE DEVELOPED TO THE WEST AND NORTHWEST OF THE HOUSTON AREA. LOOKS LIKE SUBSIDENCE IS A LITTLE STRONGER THAN ANTICIPATED... BUT THERE IS STILL TIME FOR DEVELOPMENT OVER THE NEXT COUPLE OF HOURS. DID GO AHEAD AND LOWER THIS AFTERNOON`S INLAND POPS INTO A 20% TO 30% RANGE. ALSO SHOULD KEEP OUR EYES ON DEEP SOUTH TEXAS STORMS CURRENTLY SURGING TO THE NORTH...SIMILAR TO WHAT WE SAW YESTERDAY. LATEST HRRR RUNS APPEAR TO BE PICKING THIS ACTIVITY UP...AND THEY KEEP IT ALL TO OUR WEST DURING THE LATE AFTERNOON THROUGH EARLY EVENING HOURS. WENT AHEAD AND ADDED SOME LOW POPS INTO THE EVENING HOURS ACROSS SOME OF OUR FAR WESTERN COUNTIES IN CASE SOME OF THIS HOLDS TOGETHER. APPEARS THAT WE WILL REMAIN ON THE WESTERN EDGE OF A SURFACE HIGH THAT IS CENTERED ALONG THE CENTRAL/EASTERN PORTIONS OF THE GULF OF MEXICO FOR THE NEXT SEVERAL DAYS...AND WE WILL PROBABLY BE OK WITH GOING WITH POPS AROUND 20%. BY NEXT WEEKEND... IT APPEARS POSSIBLE THAT MID/UPPER LEVEL RIDGING OUT WEST COULD HELP TO BRING A COLD FRONT INTO MAYBE THE CENTRAL PART OF THE STATE...AND THIS FEATURE COULD BECOME OUR AREA`S NEXT BEST CHANCE FOR SHOWERS AND THUNDERSTORMS. 42 && .MARINE... LIGHT TO MODERATE SOUTHEAST TO SOUTH WINDS WILL CONTINUE THROUGH THE FORECAST PERIOD WITH A RIDGE OF HIGH PRESSURE SITUATED OVER THE NORTHERN GULF OF MEXICO. IT WOULD BE MAINLY DRY GIVEN SUBSIDENCE ASSOCIATED WITH SURFACE RIDGE...ALTHOUGH AN ISOLATED SHOWER OR THUNDERSTORM WILL BE POSSIBLE ON OCCASION. 46 && .PREV DISCUSSION... /ISSUED 1255 PM CDT SUN JUN 21 2015/ DISCUSSION... UPDATED AVIATION DISCUSSION. AVIATION... LATEST VISIBLE AND RADAR IMAGERY SHOWING LOWER DECK HAVING MOSTLY THINNED OUT WITH WIND PARALLEL LINES OF INSTABILITY CUMULUS DEVELOPING. RADAR RELATIVELY QUIET WITH SHOWERS AND A FEW STORMS WELL WEST OF THE TAF SITES...AROUND PERIPHERY OF SURFACE HIGH. WITH AFTERNOON HEATING EXPECT A FEW SHOWERS AND THUNDERSTORMS TO DEVELOP...BUT COVERAGE SHOULD BE LIMITED AND CHANCES OF TSTRMS OCCURRING AT ANY TAF SITE FAIRLY LOW. WILL MAINTAIN VCSH AT NW SITES FOR NOW...FROM KIAH ON NORTH AND NORTHWEST...CLOSER TO THE PERIPHERY OF THE SURFACE HIGH AND THE EXISTING CONVECTION...WHICH COULD DROP BOUNDARIES LEADING TO NEW CONVECTION. WILL WATCH RADAR AND SATELLITE TRENDS AND ADD TSTRMS TO TAFS IF NEEDED. REMAINDER OF TAF FOLLOWS PERSISTENCE CLOSELY AS TONIGHTS PATTERN AND THERMODYNAMIC PROFILE LOOK SIMILAR TO LAST NIGHT. THIS WOULD IMPLY MVFR CIGS FROM CXO ON NORTH AND WEST OVERNIGHT...AND MAINLY SCATTERED LOWER CLOUDS ELSEWHERE. CANT RULE OUT AREAS OF BROKEN MVFR EVEN AT SOUTHERN SITES...KIAH ON SOUTH...BUT MODEL SOUNDINGS DO NOT SHOW ANY DEEPER MOIST LAYER THAN OCCURED LAST NIGHT. 46 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 75 91 75 91 75 / 20 10 0 10 10 HOUSTON (IAH) 76 92 76 92 76 / 10 20 0 20 10 GALVESTON (GLS) 80 87 80 87 79 / 10 10 0 20 10 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...42 AVIATION/MARINE...46
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1226 PM CDT SUN JUN 21 2015 .AVIATION... CEILINGS ARE SLOWLY LIFTING INTO VFR CATEGORIES AT THE PRESENT TIME. CONVECTION FORECAST IS A BIT PROBLEMATIC AS SEVERAL THINGS SEEM TO BE AT PLAY. MORNING ACTIVITY WAS PRIMARILY DRIVEN WITHIN AREA OF LOW-LEVEL LIFT TO THE EAST OF A 700 MB TROUGH AXIS. CURRENTLY ON RADAR...THERE IS SOME SORT OF BOUNDARY ORIENTED ALMOST NORTH-SOUTH...LIFTING TO THE NNW. THERE IS NOT MUCH ACTIVITY BEHIND THIS BOUNDARY...AND IT IS DIFFICULT TO GAUGE HOW MUCH REDEVELOPMENT THERE MAY BE LATER TODAY TO THE EAST. CURRENT THINKING IS NOT MUCH ADDITIONAL ACTIVITY IS GOING TO OCCUR AND WILL JUST MENTION VICINITY SHOWERS OR THUNDER IN THE NEAR TERM WITH NOTHING MENTIONED ALONG THE I-35 TAF SITES AFTER 00Z. THEREFORE...WILL AMEND IF NECESSARY. TOUGH TO PIN DOWN TIMING FOR DRT IF ANY ACTIVITY WILL OCCUR AND WILL AMEND IF CONFIDENCE INCREASES FOR CONVECTION. ANOTHER ROUND OF MVFR CEILINGS IS EXPECTED TONIGHT. && .PREV DISCUSSION... /ISSUED 1020 AM CDT SUN JUN 21 2015/ UPDATE... SCATTERED SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED IN THE PAST FEW HOURS ALONG AND EAST OF THE WEAK TROUGH AXIS...WHICH IS MOST EASILY SEEN ON THE 12Z 700 MB ANALYSIS AND IN WV IMAGERY. BASED ON THIS MORNING DEVELOPMENT...WE HAVE HIGHER CONFIDENCE IN RECENT HRRR RUNS FOR SLIGHTLY HIGHER CONVECTIVE COVERAGE AND QPF TODAY...ESPECIALLY OVER THE WINTER GARDEN AND RIO GRANDE PLAINS AREAS. THE FORECAST WAS JUST UPDATED FOR SLIGHTLY HIGHER POPS... SLIGHTLY LOWER MAX TEMPS...AND TO RE-TREND HOURLY VARIABLES THROUGH 00Z. PREV DISCUSSION... /ISSUED 617 AM CDT SUN JUN 21 2015/ AVIATION DISCUSSION...FOR 12Z TAF PACKAGE... RADAR IS PRETTY QUIET AT TAF ISSUANCE TIME. EXPECTING DEVELOPMENT OF SHOWER AND STORM ACTIVITY THIS AFTERNOON...MOSTLY IMPACTING THE KDRT TERMINAL. SOME OF THIS ACTIVITY COULD REACH AS FAR NORTH AS KAUS BUT LOW CONFIDENCE AT THE MOMENT. HOWEVER...ISOLATED ACTIVITY COULD DEVELOP DURING THE AFTERNOON SO FELT VCTS WAS WARRANTED. MVFR CIGS SHOULD IMPROVE SLOWLY TO VFR BY AFTERNOON. PREV DISCUSSION... /ISSUED 317 AM CDT SUN JUN 21 2015/ SHORT TERM (TODAY THROUGH MONDAY)...MID LEVEL TROUGH AXIS STRETCHES FROM NORTH TEXAS...SOUTHWEST INTO THE WESTERN EDWARDS PLATEAU...AND CONTINUES DEEP INTO MEXICO. THE TROUGH AXIS WILL CONTINUE TO INFLUENCE RAIN CHANCES TODAY. HIGH PRECIPITABLE WATER AIRMASS REMAINS IN PLACE ACROSS SOUTH-CENTRAL TEXAS...ESPECIALLY CENTRAL AND SOUTHWEST AREAS OF THE CWA. STRENGTHENING LOW LEVEL JET UP THE ESCARPMENT IN THE TROPICAL AIRMASS HAS LED TO ISOLATED TO SCATTERED SHOWER DEVELOPMENT EARLY THIS MORNING ALONG AND NORTH OF THE ESCARPMENT EDGE. THIS WILL CONTINUE TO BE THE FAVORED LOCATIONS THROUGH SUNRISE. MODELS SHOW SOME POTENTIAL FOR EXPANSION SOUTH AND EAST LATER THIS MORNING AS INSTABILITY INCREASES...THEN POTENTIALLY CONSOLIDATING ACROSS THE SOUTHWEST CWA...SOUTHWEST OF A KERRVILLE TO PLEASANTON LINE LATER IN THE AFTERNOON AND TONIGHT...CLOSER TO THE DEEPER MOISTURE AND FORCING FROM THE TROUGH AXIS. ENHANCEMENT IN THIS AREA POSSIBLE FROM MID LEVEL VORTICITY ADVECTION PIVOTING NORTH INTO THE AREA...AROUND MID LEVEL CYCLONIC CIRCULATION SEEN OVER SOUTH- CENTRAL COAHULIA MEXICO ON SATELLITE AND ANALYZED BY MODELS. PRECIPITABLE WATER VALUES STILL POOLED AROUND 2.1 INCHES ACROSS THE SOUTH/SOUTHWEST CWA. LOCALLY HEAVY RAINFALL WILL BE MENTIONED IN THE SOUTHWEST AREAS TODAY AND TONIGHT. MODELS INSIST DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE EAST...ACROSS THE EASTERN HALF OF THE CWA...SUNDAY NIGHT AND MONDAY...ALONG WITH MID LEVEL NVA. THE DRYING CONTINUES FURTHER WEST INTO THE CWA MONDAY NIGHT AND TUESDAY. THIS IN RESPONSE TO THE MID LEVEL RIDGE ACROSS THE NORTH-CENTRAL GULF NUDGING WEST. THIS WILL CONFINE POPS MONDAY AND TUESDAY CLOSER TO THE RIO GRANDE. BELOW NORMAL HIGH TEMPERATURES CONTINUE TODAY AND MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...GFS AND ECMWF HAVE BEEN IN DECENT AGREEMENT THAT AFTER DRYING ACROSS THE EASTERN CWA MONDAY AND TUESDAY...MOISTURE WILL INCREASE AGAIN WEDNESDAY AND THURSDAY ACROSS SOUTHERN AND EASTERN AREAS. THIS WILL LEAD TO DIURNALLY DRIVEN ISOLATED TO SCATTERED SHOWERS AND STORMS ALONG AND EAST OF I-35 BOTH DAYS. DRYING THEN TAKES PLACE AGAIN FRIDAY AND SATURDAY ACROSS MUCH OF THE CWA...WITH HIGH TEMPERATURES TRYING TO EDGE BACK TO NEAR NORMAL. JUST BEYOND THE 7 DAY...AN UPPER LEVEL RIDGE IS SHOWN TO AMPLIFY ACROSS THE WESTERN CONUS...DEEPENING A TROUGH THROUGH THE CENTRAL PLAINS AND MIDWEST. THIS COULD PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS. THERE IS A SLIGHT CHANCE UPSTREAM CONVECTION ASSOCIATED WITH THE FRONT COULD WORK INTO NORTHERN AREAS OF THE CWA ON SUNDAY AND/OR MONDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 86 74 91 73 90 / 40 20 10 0 - AUSTIN BERGSTROM INTL AIRPORT 85 73 91 72 90 / 40 20 10 0 - NEW BRAUNFELS MUNI AIRPORT 86 74 91 73 90 / 50 20 10 - - BURNET MUNI AIRPORT 85 73 90 72 90 / 40 20 10 0 - DEL RIO INTL AIRPORT 86 74 90 74 90 / 50 40 30 20 20 GEORGETOWN MUNI AIRPORT 85 73 91 73 90 / 40 20 10 0 - HONDO MUNI AIRPORT 85 74 89 72 89 / 60 40 20 - 10 SAN MARCOS MUNI AIRPORT 86 73 90 73 90 / 50 20 10 - 10 LA GRANGE - FAYETTE REGIONAL 87 75 90 74 90 / 30 10 10 0 10 SAN ANTONIO INTL AIRPORT 86 75 90 74 90 / 50 20 10 - 10 STINSON MUNI AIRPORT 86 75 90 74 90 / 50 20 10 - 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...HAMPSHIRE SYNOPTIC/GRIDS...26 PUBLIC SERVICE/DATA COLLECTION...30
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1020 AM CDT SUN JUN 21 2015 .UPDATE... SCATTERED SHOWERS AND A FEW THUNDERSTORMS HAVE DEVELOPED IN THE PAST FEW HOURS ALONG AND EAST OF THE WEAK TROUGH AXIS...WHICH IS MOST EASILY SEEN ON THE 12Z 700 MB ANALYSIS AND IN WV IMAGERY. BASED ON THIS MORNING DEVELOPMENT...WE HAVE HIGHER CONFIDENCE IN RECENT HRRR RUNS FOR SLIGHTLY HIGHER CONVECTIVE COVERAGE AND QPF TODAY...ESPECIALLY OVER THE WINTER GARDEN AND RIO GRANDE PLAINS AREAS. THE FORECAST WAS JUST UPDATED FOR SLIGHTLY HIGHER POPS... SLIGHTLY LOWER MAX TEMPS...AND TO RE-TREND HOURLY VARIABLES THROUGH 00Z. && .PREV DISCUSSION... /ISSUED 617 AM CDT SUN JUN 21 2015/ AVIATION DISCUSSION...FOR 12Z TAF PACKAGE... RADAR IS PRETTY QUIET AT TAF ISSUANCE TIME. EXPECTING DEVELOPMENT OF SHOWER AND STORM ACTIVITY THIS AFTERNOON...MOSTLY IMPACTING THE KDRT TERMINAL. SOME OF THIS ACTIVITY COULD REACH AS FAR NORTH AS KAUS BUT LOW CONFIDENCE AT THE MOMENT. HOWEVER...ISOLATED ACTIVITY COULD DEVELOP DURING THE AFTERNOON SO FELT VCTS WAS WARRANTED. MVFR CIGS SHOULD IMPROVE SLOWLY TO VFR BY AFTERNOON. PREV DISCUSSION... /ISSUED 317 AM CDT SUN JUN 21 2015/ SHORT TERM (TODAY THROUGH MONDAY)...MID LEVEL TROUGH AXIS STRETCHES FROM NORTH TEXAS...SOUTHWEST INTO THE WESTERN EDWARDS PLATEAU...AND CONTINUES DEEP INTO MEXICO. THE TROUGH AXIS WILL CONTINUE TO INFLUENCE RAIN CHANCES TODAY. HIGH PRECIPITABLE WATER AIRMASS REMAINS IN PLACE ACROSS SOUTH-CENTRAL TEXAS...ESPECIALLY CENTRAL AND SOUTHWEST AREAS OF THE CWA. STRENGTHENING LOW LEVEL JET UP THE ESCARPMENT IN THE TROPICAL AIRMASS HAS LED TO ISOLATED TO SCATTERED SHOWER DEVELOPMENT EARLY THIS MORNING ALONG AND NORTH OF THE ESCARPMENT EDGE. THIS WILL CONTINUE TO BE THE FAVORED LOCATIONS THROUGH SUNRISE. MODELS SHOW SOME POTENTIAL FOR EXPANSION SOUTH AND EAST LATER THIS MORNING AS INSTABILITY INCREASES...THEN POTENTIALLY CONSOLIDATING ACROSS THE SOUTHWEST CWA...SOUTHWEST OF A KERRVILLE TO PLEASANTON LINE LATER IN THE AFTERNOON AND TONIGHT...CLOSER TO THE DEEPER MOISTURE AND FORCING FROM THE TROUGH AXIS. ENHANCEMENT IN THIS AREA POSSIBLE FROM MID LEVEL VORTICITY ADVECTION PIVOTING NORTH INTO THE AREA...AROUND MID LEVEL CYCLONIC CIRCULATION SEEN OVER SOUTH- CENTRAL COAHULIA MEXICO ON SATELLITE AND ANALYZED BY MODELS. PRECIPITABLE WATER VALUES STILL POOLED AROUND 2.1 INCHES ACROSS THE SOUTH/SOUTHWEST CWA. LOCALLY HEAVY RAINFALL WILL BE MENTIONED IN THE SOUTHWEST AREAS TODAY AND TONIGHT. MODELS INSIST DRIER MID LEVEL AIR WORKS INTO THE AREA FROM THE EAST...ACROSS THE EASTERN HALF OF THE CWA...SUNDAY NIGHT AND MONDAY...ALONG WITH MID LEVEL NVA. THE DRYING CONTINUES FURTHER WEST INTO THE CWA MONDAY NIGHT AND TUESDAY. THIS IN RESPONSE TO THE MID LEVEL RIDGE ACROSS THE NORTH-CENTRAL GULF NUDGING WEST. THIS WILL CONFINE POPS MONDAY AND TUESDAY CLOSER TO THE RIO GRANDE. BELOW NORMAL HIGH TEMPERATURES CONTINUE TODAY AND MONDAY. LONG TERM (MONDAY NIGHT THROUGH SATURDAY)...GFS AND ECMWF HAVE BEEN IN DECENT AGREEMENT THAT AFTER DRYING ACROSS THE EASTERN CWA MONDAY AND TUESDAY...MOISTURE WILL INCREASE AGAIN WEDNESDAY AND THURSDAY ACROSS SOUTHERN AND EASTERN AREAS. THIS WILL LEAD TO DIURNALLY DRIVEN ISOLATED TO SCATTERED SHOWERS AND STORMS ALONG AND EAST OF I-35 BOTH DAYS. DRYING THEN TAKES PLACE AGAIN FRIDAY AND SATURDAY ACROSS MUCH OF THE CWA...WITH HIGH TEMPERATURES TRYING TO EDGE BACK TO NEAR NORMAL. JUST BEYOND THE 7 DAY...AN UPPER LEVEL RIDGE IS SHOWN TO AMPLIFY ACROSS THE WESTERN CONUS...DEEPENING A TROUGH THROUGH THE CENTRAL PLAINS AND MIDWEST. THIS COULD PUSH A RARE LATE JUNE COLD FRONT INTO NORTH-CENTRAL TEXAS. THERE IS A SLIGHT CHANCE UPSTREAM CONVECTION ASSOCIATED WITH THE FRONT COULD WORK INTO NORTHERN AREAS OF THE CWA ON SUNDAY AND/OR MONDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 86 74 91 73 90 / 40 20 10 0 - AUSTIN BERGSTROM INTL AIRPORT 85 73 91 72 90 / 40 20 10 0 - NEW BRAUNFELS MUNI AIRPORT 86 74 91 73 90 / 50 20 10 - - BURNET MUNI AIRPORT 85 73 90 72 90 / 40 20 10 0 - DEL RIO INTL AIRPORT 86 74 90 74 90 / 50 40 30 20 20 GEORGETOWN MUNI AIRPORT 85 73 91 73 90 / 40 20 10 0 - HONDO MUNI AIRPORT 85 74 89 72 89 / 60 40 20 - 10 SAN MARCOS MUNI AIRPORT 86 73 90 73 90 / 50 20 10 - 10 LA GRANGE - FAYETTE REGIONAL 87 75 90 74 90 / 30 10 10 0 10 SAN ANTONIO INTL AIRPORT 86 75 90 74 90 / 50 20 10 - 10 STINSON MUNI AIRPORT 86 75 90 74 90 / 50 20 10 - 10 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...HAMPSHIRE SYNOPTIC/GRIDS...26 PUBLIC SERVICE/DATA COLLECTION...30
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AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
918 PM EDT MON JUN 22 2015 .SYNOPSIS... WE WILL CONTINUE TO EXPERIENCE AN ACTIVE WEATHER PATTERN THROUGH THE REMAINDER OF THE WEEK. THE COMBINATION OF DAYTIME HEATING AND DISTURBANCES MOVING INTO AND THROUGH THE REGION FROM THE NORTHWEST...WILL KEEP SHOWERS AND STORMS IN THE FORECAST EACH DAY. THE PATTERN WILL CONTINUE THIS COMING WEEKEND INTO EARLY NEXT WEEK...BUT TEMPERATURE TRENDS WILL TURN COOLER. && .NEAR TERM /THROUGH TUESDAY/... AS OF 918 PM EDT MONDAY... ISOLATED CONVECTION WILL DISSIPATE WITH THE LOSS OF SOLAR HEATING TONIGHT. PARTLY CLOUDY SKIES WILL PREVAIL OVERNIGHT. THE COMBINATION OF LOW LEVEL MOISTURE AND LIGHT WINDS WILL RESULT IN PATCHY FOG OVERNIGHT INTO TUESDAY MORNING. LOW TEMPERATURES WILL BE MILD WITH READINGS FROM THE MID 60S IN THE MOUNTAINS TO AROUND 70 DEGREES ACROSS THE PIEDMONT. COLD FRONT ACROSS THE OHIO VALLEY WILL SLOWLY DROP SOUTHEAST TUESDAY. AN OUTFLOW AND THE BOUNDARY WILL ENTER OUR REGION TUESDAY AFTERNOON. THESE BOUNDARY AND SOLAR HEATING WILL GENERATE SHOWERS AND THUNDERSTORMS.THE LATEST DAY 2 CONVECTIVE OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF SEVERE WEATHER. THE GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS AND HAIL WITH SOME OF THE STORMS TUESDAY AFTERNOON INTO TUESDAY EVENING. HIGHS TUESDAY WILL CLIMB IN THE MID 80S TO AROUND 90 IN THE MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICIES WILL CLIMB TO AROUND 100 ROUGHLY ALONG AND EAST OF A REIDSVILLE NORTH CAROLINA TO BUCKINGHAM VIRGINIA LINE LATE IN THE AFTERNOON. RECORD HIGH TEMPERATURES ARE POSSIBLE TUESDAY. REFER TO CLIMATE SECTION FOR THE CURRENT RECORDS. AS OF 630 PM EDT MONDAY... DECREASED POPS FOR TONIGHT. MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND CLOUD COVER FOR THIS EVENING INTO TONIGHT. AS OF 522 PM EDT MONDAY... MADE SOME MINOR ADJUSTMENTS IN POPS AND WEATHER WITH LATEST RADAR TRENDS AND BLENDED TOWARDS THE RNK WRFARW AND HRRR FOR THIS EVENING INTO TONIGHT. ALSO MODIFIED TEMPERATURES FOR THIS EVENING WITH LATEST OBS AND CONVECTION. MORE CHANGES LATER TONIGHT. AS OF 230 PM EDT MONDAY... ISOLATED SHOWERS HAVE STARTED TO DEVELOP ALONG THE CREST OF THE BLUE RIDGE IN NORTH CAROLINA...AND ALSO NORTH OF I-64. AS THE AFTERNOON CONTINUES...ADDITIONAL HEATING IS EXPECTED TO PROMPT MORE SHOWER AND THUNDERSTORM DEVELOPMENT. THE BULK OF THE CONVECTION IS EXPECTED TO BE ACROSS WESTERN INTO SOUTHERN PARTS OF THE AREA...FOLLOWING THE PATH OF THE REMNANTS OF A THUNDERSTORM COMPLEX THAT DISSIPATED OVER EASTERN KENTUCKY EARLY THIS MORNING. OVERNIGHT...THE EVENING CONVECTION IS EXPECTED TO EXIT THE REGION OR DISSIPATE COMPLETELY BY 10PM-11PM. AFTER THIS TIME...CLOUDS WILL TREND TO PARTLY CLOUDY TROUGH ROUGHLY 2-3AM TUESDAY. AFTER THIS TIME FRAME...SOME GUIDANCE HINTS AT A RESURGENCE OF LOW LEVEL MOISTURE ACROSS WESTERN PARTS OF THE REGION...SO A RETURN TO MOSTLY CLOUDY SKIES IN AREAS BETWEEN ROUGHLY BLUEFIELD TO LEWISBURG WEST VIRGINIA IS POSSIBLE. PATCHY LATE NIGHT AND EARLY MORNING FOG WILL BE POSSIBLE...ESPECIALLY IN THE RIVER AND MOUNTAIN VALLEYS WERE ANY SUBSTANTIAL PRECIPITATION FALLS THIS AFTERNOON AND EVENING. LOW TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE. READINGS IN THE MID TO UPPER 60S ARE EXPECTED ACROSS THE MOUNTAINS WITH UPPER 60S TO AROUND 70 ACROSS THE PIEDMONT. ON TUESDAY...THE FEATURE THAT IS CURRENTLY PROGRESSING THROUGH THE GREAT LAKES REGION IS EXPECTED TO BE IMPACTING OUR WEATHER. AS THIS SYSTEM HEADS SOUTHEAST....OUTFLOW AHEAD OF IT WILL ENTER OUR REGION TOMORROW AFTERNOON. THIS BOUNDARY AND ASSOCIATED DAYTIME HEATING WILL HELP GENERATE SHOWERS AND STORMS. THE LATEST DAY 2 CONVECTIVE OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF SEVERE WEATHER IN ASSOCIATION WITH THIS THUNDERSTORM ACTIVITY. THE GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS WITH SOME OF THE STORMS. OUR FORECAST WILL REFLECT AN AFTERNOON ARRIVAL...WITH THE BEST ACTIVITY ACROSS THE NORTHERN THIRD OF THE AREA BY THE LATE AFTERNOON. PORTIONS OF THE NORTH CAROLINA PIEDMONT AND FOOTHILLS MAY NEED TO WAIT UNTIL TUESDAY EVENING FOR THE ACTIVITY TO ARRIVE. TEMPERATURES ON TUESDAY ARE FORECAST TO BE THE HOTTEST OF THE WEEK THANKS TO INCREASING 850 MB TEMPS OF ABOUT 20 C IN THE WEST AND 24 C IN THE EAST. HIGHS ARE FORECAST IN THE MID 80S TO AROUND 90 IN THE MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICIES WILL BRIEFLY TOUCH THE 100 TO 102 RANGE ROUGHLY ALONG AND EAST OF A REIDSVILLE NC TO BUCKINGHAM VA LINE LATE IN THE AFTERNOON. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 300 PM EDT MONDAY... NORTHERN STREAM ALOFT REMAINS LINED UP FROM SOUTHWEST CANADA INTO NEW ENGLAND THROUGH THURSDAY. 500 MB HEIGHTS OVER THE MID ATLANTIC REGION REMAIN CLOSE TO 590DM WITH A PIECE OF THE UPPER RIDGE STILL OVER THE SOUTHEAST UNITED STATES. WITH THIS PATTERN...LITTLE CHANGE IS EXPECTED IN THE WEATHER THROUGH THURSDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND WITH DAILY SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. EXTENT...SEVERITY AND TIMING OF THE PRECIPITATION WILL DEPEND ON THE CONVECTIVE COMPLEXES UPSTREAM OF THE FORECAST AREA AND WHERE THE RESIDUAL OUTFLOW BOUNDARIES ARE EACH DAY AT THE TIME OF MAXIMUM HEATING. THE SURFACE FRONT WILL BE IN THE NORTHERN PART OF THE FORECAST AREA ON TUESDAY EVENING AND SOUTH OF THE FORECAST AREA ON WEDNESDAY. THIS FRONT AND RESIDUAL OUTFLOW BOUNDARIES WILL BE THE MAIN TRIGGERS FOR SHOWERS AND THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY. NCEP FAVORS THE ECMWF SOLUTION OF A WAVE DEVELOPING ALONG THE FRONT OVER THE OHIO VALLEY THEN TRACKING INTO THE MID ATLANTIC REGION ON THURSDAY. SO THE PROBABILITY OF PRECIPITATION FOR THE AREA WILL CONTINUE. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /01Z TUESDAY THROUGH SATURDAY/... AS OF 731 PM EDT MONDAY... VFR CONDITIONS WILL PREVAIL THIS EVENING INTO TONIGHT. THERE COULD BE A FEW SPOTS OF MVFR VSBYS IN THE PREFERRED RIVER AND MOUNTAIN VALLEYS. ALSO...GUIDANCE IS SUGGESTED A RESURGENCE OF MVFR LEVEL MOISTURE ACROSS WESTERN PARTS OF THE AREA. COULD SEE A MVFR CIG ALONG AND NEAR A KBLF-KLWB LINE. ON TUESDAY...ANY SUB-VFR CONDITIONS SHOULD IMPROVE TO VFR BY THE LATE MORNING. LIMITED CHANCES OF PRECIPITATION EXIST THROUGH THE END OF THE CURRENT TAF FORECAST PERIOD. ISOLATED SHOWERS OR STORMS MAY DEVELOP OF MOVE INTO THE KBLF-KLWB AREA OR PARTS WEST AROUND 18Z/2PM. TUESDAY AFTERNOON AND EVENING...A COLD FRONT WILL APPROACH AND THEN CROSS THE AREA. ANTICIPATE INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE TAF PERIOD. EXTENDED AVIATION DISCUSSION... MVFR SCT TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS OF AREAS OF FOG TUESDAY EVENING INTO WEDNESDAY MORNING. HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY. BELOW ARE THE CURRENT RECORDS. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/KK SHORT TERM...AMS LONG TERM...AMS AVIATION...DS/KK CLIMATE...CF EQUIPMENT...DS/CF
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
731 PM EDT MON JUN 22 2015 .SYNOPSIS... WE WILL CONTINUE TO EXPERIENCE AN ACTIVE WEATHER PATTERN THROUGH THE REMAINDER OF THE WEEK. THE COMBINATION OF DAYTIME HEATING AND DISTURBANCES MOVING INTO AND THROUGH THE REGION FROM THE NORTHWEST...WILL KEEP SHOWERS AND STORMS IN THE FORECAST EACH DAY. THE PATTERN WILL CONTINUE THIS COMING WEEKEND INTO EARLY NEXT WEEK...BUT TEMPERATURE TRENDS WILL TURN COOLER. && .NEAR TERM /THROUGH TUESDAY/... AS OF 630 PM EDT MONDAY... DECREASED POPS FOR TONIGHT. MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND CLOUD COVER FOR THIS EVENING INTO TONIGHT. AS OF 522 PM EDT MONDAY... MADE SOME MINOR ADJUSTMENTS IN POPS AND WEATHER WITH LATEST RADAR TRENDS AND BLENDED TOWARDS THE RNK WRFARW AND HRRR FOR THIS EVENING INTO TONIGHT. ALSO MODIFIED TEMPERATURES FOR THIS EVENING WITH LATEST OBS AND CONVECTION. MORE CHANGES LATER TONIGHT. AS OF 230 PM EDT MONDAY... ISOLATED SHOWERS HAVE STARTED TO DEVELOP ALONG THE CREST OF THE BLUE RIDGE IN NORTH CAROLINA...AND ALSO NORTH OF I-64. AS THE AFTERNOON CONTINUES...ADDITIONAL HEATING IS EXPECTED TO PROMPT MORE SHOWER AND THUNDERSTORM DEVELOPMENT. THE BULK OF THE CONVECTION IS EXPECTED TO BE ACROSS WESTERN INTO SOUTHERN PARTS OF THE AREA...FOLLOWING THE PATH OF THE REMNANTS OF A THUNDERSTORM COMPLEX THAT DISSIPATED OVER EASTERN KENTUCKY EARLY THIS MORNING. OVERNIGHT...THE EVENING CONVECTION IS EXPECTED TO EXIT THE REGION OR DISSIPATE COMPLETELY BY 10PM-11PM. AFTER THIS TIME...CLOUDS WILL TREND TO PARTLY CLOUDY TROUGH ROUGHLY 2-3AM TUESDAY. AFTER THIS TIME FRAME...SOME GUIDANCE HINTS AT A RESURGENCE OF LOW LEVEL MOISTURE ACROSS WESTERN PARTS OF THE REGION...SO A RETURN TO MOSTLY CLOUDY SKIES IN AREAS BETWEEN ROUGHLY BLUEFIELD TO LEWISBURG WEST VIRGINIA IS POSSIBLE. PATCHY LATE NIGHT AND EARLY MORNING FOG WILL BE POSSIBLE...ESPECIALLY IN THE RIVER AND MOUNTAIN VALLEYS WERE ANY SUBSTANTIAL PRECIPITATION FALLS THIS AFTERNOON AND EVENING. LOW TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE. READINGS IN THE MID TO UPPER 60S ARE EXPECTED ACROSS THE MOUNTAINS WITH UPPER 60S TO AROUND 70 ACROSS THE PIEDMONT. ON TUESDAY...THE FEATURE THAT IS CURRENTLY PROGRESSING THROUGH THE GREAT LAKES REGION IS EXPECTED TO BE IMPACTING OUR WEATHER. AS THIS SYSTEM HEADS SOUTHEAST....OUTFLOW AHEAD OF IT WILL ENTER OUR REGION TOMORROW AFTERNOON. THIS BOUNDARY AND ASSOCIATED DAYTIME HEATING WILL HELP GENERATE SHOWERS AND STORMS. THE LATEST DAY 2 CONVECTIVE OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF SEVERE WEATHER IN ASSOCIATION WITH THIS THUNDERSTORM ACTIVITY. THE GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS WITH SOME OF THE STORMS. OUR FORECAST WILL REFLECT AN AFTERNOON ARRIVAL...WITH THE BEST ACTIVITY ACROSS THE NORTHERN THIRD OF THE AREA BY THE LATE AFTERNOON. PORTIONS OF THE NORTH CAROLINA PIEDMONT AND FOOTHILLS MAY NEED TO WAIT UNTIL TUESDAY EVENING FOR THE ACTIVITY TO ARRIVE. TEMPERATURES ON TUESDAY ARE FORECAST TO BE THE HOTTEST OF THE WEEK THANKS TO INCREASING 850 MB TEMPS OF ABOUT 20 C IN THE WEST AND 24 C IN THE EAST. HIGHS ARE FORECAST IN THE MID 80S TO AROUND 90 IN THE MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICIES WILL BRIEFLY TOUCH THE 100 TO 102 RANGE ROUGHLY ALONG AND EAST OF A REIDSVILLE NC TO BUCKINGHAM VA LINE LATE IN THE AFTERNOON. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY/... AS OF 300 PM EDT MONDAY... NORTHERN STREAM ALOFT REMAINS LINED UP FROM SOUTHWEST CANADA INTO NEW ENGLAND THROUGH THURSDAY. 500 MB HEIGHTS OVER THE MID ATLANTIC REGION REMAIN CLOSE TO 590DM WITH A PIECE OF THE UPPER RIDGE STILL OVER THE SOUTHEAST UNITED STATES. WITH THIS PATTERN...LITTLE CHANGE IS EXPECTED IN THE WEATHER THROUGH THURSDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND WITH DAILY SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. EXTENT...SEVERITY AND TIMING OF THE PRECIPITATION WILL DEPEND ON THE CONVECTIVE COMPLEXES UPSTREAM OF THE FORECAST AREA AND WHERE THE RESIDUAL OUTFLOW BOUNDARIES ARE EACH DAY AT THE TIME OF MAXIMUM HEATING. THE SURFACE FRONT WILL BE IN THE NORTHERN PART OF THE FORECAST AREA ON TUESDAY EVENING AND SOUTH OF THE FORECAST AREA ON WEDNESDAY. THIS FRONT AND RESIDUAL OUTFLOW BOUNDARIES WILL BE THE MAIN TRIGGERS FOR SHOWERS AND THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY. NCEP FAVORS THE ECMWF SOLUTION OF A WAVE DEVELOPING ALONG THE FRONT OVER THE OHIO VALLEY THEN TRACKING INTO THE MID ATLANTIC REGION ON THURSDAY. SO THE PROBABILITY OF PRECIPITATION FOR THE AREA WILL CONTINUE. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 731 PM EDT MONDAY... VFR CONDITIONS WILL PREVAIL THIS EVENING INTO TONIGHT. THERE COULD BE A FEW SPOTS OF MVFR VSBYS IN THE PREFERRED RIVER AND MOUNTAIN VALLEYS. ALSO...GUIDANCE IS SUGGESTED A RESURGENCE OF MVFR LEVEL MOISTURE ACROSS WESTERN PARTS OF THE AREA. COULD SEE A MVFR CIG ALONG AND NEAR A KBLF-KLWB LINE. ON TUESDAY...ANY SUB-VFR CONDITIONS SHOULD IMPROVE TO VFR BY THE LATE MORNING. LIMITED CHANCES OF PRECIPITATION EXIST THROUGH THE END OF THE CURRENT TAF FORECAST PERIOD. ISOLATED SHOWERS OR STORMS MAY DEVELOP OF MOVE INTO THE KBLF-KLWB AREA OR PARTS WEST AROUND 18Z/2PM. TUESDAY AFTERNOON AND EVENING...A COLD FRONT WILL APPROACH AND THEN CROSS THE AREA. ANTICIPATE INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. HIGH CONFIDENCE IN CEILINGS...VISIBILITIES AND WINDS DURING THE TAF PERIOD. EXTENDED AVIATION DISCUSSION... MVFR SCT TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS OF AREAS OF FOG TUESDAY EVENING INTO WEDNESDAY MORNING. HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY. BELOW ARE THE CURRENT RECORDS. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/KK SHORT TERM...AMS LONG TERM...AMS AVIATION...DS/KK CLIMATE...CF EQUIPMENT...DS
YOU CAN SEE AN ILLUSTRATED VERSION OF THIS FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML

Area Forecast Discussion National Weather Service Spokane WA 230 PM PDT SUN JUN 21 2015 .SYNOPSIS... Westerly floe with several week disturbances will result in a chance for showers and thunderstorms through about mid-week across the northern mountains. Temperatures will remain warmer than normal for this time of year. A strong ridge of high pressure will build into the region by the weekend resulting in very warm temperatures and sunny skies. && .DISCUSSION... Tonight through Monday night: Satellite reveals a weak trof along the coast and an influx of mid and high level moisture under broad southwesterly flow. A SW to NE ribbon of instability stretches from south-central Oregon to Missoula, MT where we are seeing scattered thunderstorms. Per latest HRRR and deterministic models, this should remain nearly stationary...residing just south of my Blue Mtns and Camas Prairie zones. We are seeing numerous weak echoes north of this instability which is bringing passing virga and sprinkles. There is still a small chance for an isolated thunderstorm near the Cascade Crest with RUC13 data showing up to 800 J/kg sb cape along and west of the CAPE. The coastal shortwave will track inland on Monday and along the International Border Monday night. Surface based instability Monday afternoon will keep a small risk for thunderstorms in the Cascades then transition toward a nocturnal shower or thunderstorm event as the wave tracks along the Canadian Border. This is no slam dunk by any means but this is where models agree on the best forcing. The NAM is a bit deeper with this wave but has little support from the SREF. Nonetheless...we will need to keep an eye on trends as the deeper shortwave could allow eLevated convection possible into far southeast as well. Temperatures the next 48 hours will remain mild with highs in the 70s to 80s and lows in the upper 40s to lower 60s. Winds will be light. /sb Tuesday through Thursday...Westerly flow will be across the region with a couple of weak short wave disturbances moving through southern B.C. Monday night/Tuesday, again on Thursday, with weak riding on Wednesday in between systems. The models are generating some Pacific moisture with both of these waves and that will help to destabilize the atmosphere late in the day. Showers and thunderstorms will be possible along and just south of the Canadian border...and mainly tied to the higher terrain where up- sloping flow will give a little boost to the lifting process. It doesn`t look like any of these showers or thunderstorms will be particularly strong, but enough moisture will be available for brief very heavy showers at times. Otherwise sunny and warm with temperatures 5-10 degrees above seasonal averages. Friday and through the weekend a strong ridge of high pressure will build into the west and will turn the weather very hot, very dry and sunny into the first part of next week. As was mentioned in previous discussions it`s gonna be a hot one. 850 mb temps increase to 22-23C Friday and up to 28-30C by Sunday. This will result in temps in the 90s Friday...mid 90s to just above 100 on Saturday and scorching on Sunday with highs in the upper 90s to around 105-107, this is about 20 degrees above normal. In addition relative humidity will drop into the teens with several areas drying out into the single digits...and poor recoveries on mid slopes and ridges. The fuels that carry fire are already drier then average and the hot dry conditions will dry the fuels out further...to historic levels. Luckily not much wind is expected under the ridge. Looking further out into the following week for the last few days of June it doesn`t look like the ridge will have any tendency to break down and the temperatures will remain just as hot if not a few degrees hotter. I may have mentioned this earlier in this discussion, but it`s gonna be hot. Tobin && .AVIATION... 18Z TAFS: Middle and high clouds associated with a weak weather disturbance moving up from the south will pass over the aviation area today. A few midlevel cells will bring the potential for isolated sprinkles but little in the way of precipitation. Isolated thunderstorms will be possible near the Cascade Crest btwn 22-03z. Breezy northerly winds are currently coming down the Okanogan Valley but should diminish aft 21z. /sb && .PRELIMINARY POINT TEMPS/POPS... Spokane 56 82 56 82 56 87 / 0 10 10 10 0 0 Coeur d`Alene 52 81 54 81 52 86 / 10 10 10 10 10 0 Pullman 48 79 50 79 48 84 / 10 10 10 10 0 0 Lewiston 58 86 59 87 57 92 / 10 10 10 10 0 0 Colville 52 84 53 85 53 90 / 10 10 20 20 10 10 Sandpoint 46 80 49 80 48 85 / 10 10 10 10 10 10 Kellogg 50 79 51 80 49 85 / 10 10 10 20 10 10 Moses Lake 57 87 56 87 57 92 / 0 10 10 0 0 0 Wenatchee 64 85 62 89 65 93 / 10 10 10 10 0 0 Omak 55 86 55 88 56 92 / 10 10 10 20 10 10 && .OTX WATCHES/WARNINGS/ADVISORIES... ID...None. WA...None. && $$
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
917 PM CDT MON JUN 22 2015 .UPDATE...ISOLATED SHOWERS AND TSTORMS CONTINUE TO POP UP IN THE INSTABILITY AXIS ACROSS SOUTHEAST WISCONSIN AHEAD OF APPROACHING CDFNT. LOW LEVEL CONVERGENCE ALONG FRONT FAIRLY WEEK WHILE STRONGER SYNOPTIC FORCING EXITING NORTHEAST WI. WILL CONTINUE LOW POPS FOR SEVERAL MORE HOURS ACROSS SE CWA UNTIL FRONT PASSES AND DRIER...LESS HUMID CONDITIONS SURGE ACROSS THE AREA. WL PROBABLY NUDGE OVERNIGHT LOW TEMPS UP A DEGREE OR TWO IN THE EAST. && .AVIATION/06Z TAFS/...MVFR STRATUS HAS MIXED OUT MOST AREAS. EXCEPT FOR A STRAY SHOWER AFFECTING ERN TAF SITES NEXT SEVERAL HOURS...EXPECT LINGERING SCT LOW AND MID CLOUDS TO THIN WITH CS SHIELD OVER SRN THINNING LATER IN THE NIGHT AS NRN IL CONVECTION GRADUALLY WANES. && .MARINE...WL LET SMALL CRAFT ADVY EXPIRE AT 03Z AS PRESSURE GRADIENT HAS FINALLY WEAKENED AHEAD OF APPROACHING CDFNT. WINDS WL PICK UP AGAIN LATER TONIGHT FROM THE NORTHWEST. MAY HAVE A FEW GUSTS APPROACH SMALL CRAFT ADVY CRITERIA CLOSE TO SHORE BUT COOLER LAKE MI WATERS WL PREVENT STRONGER GUSTS FROM MIXING TO LAKE SFC. && .PREV DISCUSSION... /ISSUED 351 PM CDT MON JUN 22 2015/ SHORT TERM... TONIGHT AND TUESDAY...FORECAST CONFIDENCE IS MEDIUM. SWLY WIND GUSTS MAINLY IN THE 30 MPH RANGE WILL CONTINUE UNTIL THE MIXING CEASES TOWARD EVENING. OTHERWISE CHANCES OF TSTORMS REMAIN FOR THE LATE AFTERNOON AND EARLY EVENING AS CAPE BUILDS AND CIN WEAKENS ALONG THE COLD FRONT OVER WRN WI. OVERALL THOUGH BELIEVE SOME CIN WILL REMAIN OVER THE CWA AND LIMIT TSTORM POTENTIAL WITH ONLY LOW CHANCES OF SVR TSTORMS. THE LATEST HRRR MODEL ONLY INDICATES MINOR DEVELOPMENT OVER SRN WI BUT MORE ROBUST DEVELOPMENT OVER ERN IA AND NRN IL. COLD AND DRY AIR ADVECTION TO THEN PREVAIL LATER TONIGHT INTO TUE AM. HIGH PRESSURE TO BUILD INTO WI LATE ON TUE. A PLEASANT SUMMER DAY IS EXPECTED WITH LOW RELATIVE HUMIDITY. LAKE BREEZE DEVELOPMENT IS EXPECTED IN THE AFTERNOON. WEDNESDAY AND THURSDAY...FORECAST CONFIDENCE IS MEDIUM. A SHORTWAVE EMBEDDED IN NW FLOW ALOFT IN CONJUNCTION WITH THE EXIT REGION OF A ZONAL JET STREAK WILL PROVIDE UPPER LEVEL SUPPORT FOR SHOWERS AND THUNDERSTORMS DURING THIS PERIOD...ESPECIALLY WEDNESDAY AFTERNOON THROUGH THURSDAY MORNING. CLOSER TO THE SURFACE...LOW PRESSURE OVER THE CENTRAL PLAINS WILL MOVE NORTHWEST INTO THE REGION...REACHING SOUTHERN WISCONSIN SOMETIME WEDNESDAY EVENING OR THURSDAY MORNING. THE LOW TO MID LEVELS BECOME SATURATED JUST THE ARRIVAL OF THE LOW...SETTING THE STAGE FOR SHOWERS. MODEST INSTABILITY...ALONG WITH MODERATE TO STRONG SHEAR..WILL SUPPORT SHOWERS AND THUNDERSTORMS FROM WEDNESDAY AFTERNOON THROUGH THURSDAY. THERE IS SOME DISAGREEMENT AMONG THE MODELS REGARDING THE TIMING AND INTENSITY OF THIS SYSTEM. GFS/GEM COME IN WITH A RELATIVELY DEEP LOW AND PRECIP BULLSEYE EARLY THURSDAY MORNING WHILE THE ECMWF BRINGS A MORE MEAGER LOW SOUTH OF THE FORECAST AREA WITH LESS PRECIP FOR SOUTHERN WISCONSIN. LONG TERM... FRIDAY AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM. AFTER THE PREVIOUSLY MENTIONED SHORTWAVE SWINGS THROUGH THE AREA...SE WI WILL BE ENTRENCHED IN NW FLOW ALOFT WITH LITTLE SUPPORT FOR UPWARD MOTION. LATEST GFS CONTINUES TO PRODUCE A FEW ROUNDS OF VERY LIGHT QPF WHILE THE EURO REMAINS DRY. WILL BE KEEPING SOME PRECIP CHANCES TO ACCOUNT FOR GFS QPF...BUT AT THIS POINT HAVE LOW CONFIDENCE FOR PRECIP. SUNDAY AND MONDAY...FORECAST CONFIDENCE IS MEDIUM. THE ECMWF AND GFS ARE IN GOOD AGREEMENT WITH THE INTENSITY AND TIMING OF AN UPPER-LEVEL SHORTWAVE TROF/SURFACE LOW PRESSURE SYSTEM THAT WILL MOVE THROUGH SOUTHERN WISCONSIN DURING THIS PERIOD. GIVEN MODEST THE INSTABILITY IN BOTH MODELS...THERE IS A SHOT AT SHOWERS AND THUNDERSTORMS BEGINNING ON SUNDAY AFTERNOON AND CONTINUING INTO MONDAY MORNING. AVIATION/00Z TAFS/... GUSTY SWLY WINDS WILL PREVAIL INTO THE EARLY EVENING BEFORE DIMINISHING WITH SUNSET. ALSO BROKEN STRATOCUMULUS FROM 1.5-3.0 KFT WILL OVERSPREAD SOUTH CENTRAL WI AHEAD OF AN APPROACHING COLD FRONT LATE THIS AFTERNOON AND EARLY EVENING. THE STRATOCUMULUS MAY MOVE INTO SE WI AS WELL BUT CONFIDENCE IS LOW. OTHERWISE...CHANCES OF SHOWERS AND TSTORMS ARE POSSIBLE WITH THE COLD FRONT PASSAGE. VFR CONDITIONS AND CLEARING SKIES ARE EXPECTED LATE THIS EVENING. VFR CONDITIONS TO PREVAIL ON TUE. MARINE... BREEZY SWLY WINDS WITH WIND GUSTS APPROACHING GALE FORCE WILL CONTINUE INTO THE EARLY EVENING BEFORE WEAKENING. A SMALL CRAFT ADVISORY IS IN EFFECT UNTIL 10 PM. BEACHES... A BEACH HAZARD STATEMENT WILL REMAIN IN EFFECT FOR THE BEACHES OF SHEBOYGAN COUNTY DUE TO BREEZY SOUTH TO SOUTHEAST WINDS. THE WINDS WILL EVENTUALLY VEER SOUTHWEST BUT THIS MAY NOT OCCUR UNTIL THE EARLY EVENING. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 10 PM CDT THIS EVENING FOR LMZ643>646. && $$ UPDATE...MBK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
615 PM CDT MON JUN 22 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 247 PM CDT MON JUN 22 2015 CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED SUBTROPICAL RIDGING ENCOMPASSING MUCH OF THE SOUTHERN U.S. WHILE MAINLY ZONAL FLOW WAS OVER THE NORTHERN U.S.. WITHIN THIS FLOW...A POTENT SHORTWAVE TROUGH WAS CROSSING NORTHERN MN WHILE THE SHORTWAVE THAT FORMED FROM THIS MORNINGS CONVECTION WAS OVER LOWER MI. SUBSIDENCE IN THE WAKE OF THE CONVECTIVE SHORTWAVE...COMBINED WITH CLEARING NOT OCCURRING UNTIL EARLY THIS AFTERNOON...HAS HELPED TO PREVENT ADDITIONAL CONVECTION FROM FIRING. RAP DEPICTING ANYWHERE FROM 50 TO 200 J/KG OF MLCIN. THIS WAS DESPITE A COLD FRONT TRACKING THROUGH THE FORECAST AREA ASSOCIATED WITH THE POTENT TROUGH. THAT FRONT WAS NOW LOCATED FROM NORTHEAST WISCONSIN THROUGH SOUTHWEST IOWA. MUCH DRIER AIR FLOWING IN BEHIND THE FRONT...NOTED BY PRECIPITABLE WATER IN THE 2 INCH RANGE OVER SOUTHEAST IOWA TO 0.5-0.75 INCHES IN THE DAKOTAS AND CENTRAL MN. SOME STRATOCUMULUS DEVELOPMENT HAS OCCURRED IMMEDIATELY BEHIND THE FRONT AS WELL...ASSOCIATED WITH MOISTURE TRAPPED IN THE COLD FRONTAL INVERSION. TEMPERATURES ARE MOSTLY IN THE 70S TO LOWER 80S. MUCH QUIETER SHORT TERM PERIOD EXPECTED. THE POTENT SHORTWAVE TROUGH OVER MN WILL CONTINUE ITS MARCH QUICKLY EASTWARD TOWARDS EASTERN ONTARIO BY 12Z TUE. EXPECT SUBSIDENCE AND DRYING TO SPREAD INTO THE FORECAST AREA THIS EVENING BEHIND THE TROUGHS COLD FRONTAL PASSAGE. THAT FRONT SHOULD CLEAR THE AREA BY 00Z...TAKING ANY CONVECTION CHANCES WITH IT...WHICH ARE MINIMAL DUE TO ALL OF THE MLCIN...LACK OF CONVERGENCE ALONG THE FRONT AND BEING IN THE RIGHT EXIT REGION OF A 100KT JET CORE TRACKING INTO NORTHERN WI. MAY STILL HAVE TO DEAL WITH SOME POST-FRONTAL STRATOCUMULUS...BUT THAT TOO SHOULD CLEAR BY 06Z AS DRIER AIR CONTINUES TO WORK IN. ALL OF TUESDAY LOOKS TO REMAIN DRY...THOUGH SOME MID CLOUDS SHOULD SPREAD ACROSS THE AREA DURING THE DAY ASSOCIATED WITH MID LEVEL FRONTOGENESIS. WINDS WILL GRADUALLY DIMINISH DURING THE NIGHT AS HIGH PRESSURE BUILDS IN. COULD SEE SOME PATCHY FOG DEVELOP IN OUR TYPICAL COLD SPOTS AS A RESULT WITH WINDS DECOUPLING THERE AND RECENT RAIN...BUT ENOUGH WIND LOOKS TO CONTINUE TO PREVENT FOG ELSEWHERE. LOWS IN THE 50S TO LOW 60S PER GUIDANCE SEEMS REASONABLE. 925MB TEMPS OF 16-18C ON TUESDAY SHOULD RESULT IN HIGHS IN THE 70S WITH A FEW LOW 80S POSSIBLE IN RIVER VALLEYS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 247 PM CDT MON JUN 22 2015 MUCH OF THE LONG TERM PERIOD THE FORECAST AREA RESIDES IN NORTHWEST FLOW ALOFT...WHICH BECOMES EVEN MORE NORTHERLY FOR THE WEEKEND INTO EARLY NEXT WEEK AS ANAMOULSY STRONG SUBTROPICAL RIDGING BUILDS OVER THE WESTERN U.S.. THIS TYPE OF PATTERN WILL HOLD TEMPERATURES AT OR BELOW SEASONABLE NORMS. ON THE PRECIPITATION SIDE OF THINGS...A COUPLE OF TIME PERIODS OF CONCERN... 1. WEDNESDAY. A SHORTWAVE COMING OUT OF NEBRASKA AND SOUTH DAKOTA LOOKS TO TRACK INTO ILLINOIS. THIS SHORTWAVE WILL HELP TO PULL THE CURRENT FRONTAL BOUNDARY...WHICH STALLS NEAR I-70 ON TUESDAY...BACK NORTHWARD. THE QUESTION IS HOW FAR NORTH. THE ECMWF IS FARTHEST SOUTH...HOLDING IT OVER NORTHERN MO...WHILE THE GFS...NAM AND CANADIAN PULL IT AT LEAST TO I-80. SHOWERS AND THUNDERSTORMS... ISENTROPICALLY AND FRONTOGENETICALLY DRIVEN ON ITS NORTH SIDE...MAY TRY TO MAKE A RUN TOWARDS THE FORECAST AREA. HOWEVER...CONVECTIVE OUTFLOWS FROM THE PRECIPITATION MAY TEND TO HOLD THE FRONT BACK. ADDITIONALLY...THE FRONT IS PARALLEL TO THE UPPER FLOW WHICH ISNT GOOD FOR LIFTING IT NORTHWARD. THEREFORE...HAVE TRENDED PRECIPITATION CHANCES DOWN WITH THE HIGHEST CHANCES IN NORTHEAST IOWA CLOSEST TO THE FRONTAL BOUNDARY. 2. WEDNESDAY NIGHT INTO THURSDAY. ANOTHER SERIES OF SHORTWAVES ARE PROGGED TO COME OUT OF THE DAKOTAS THROUGH THE FORECAST AREA. HOW MUCH PRECIPITATION THEY PRODUCE WILL DEPEND ON HOW FAR NORTH THAT WARM FRONTAL BOUNDARY GETS ON WEDNESDAY. LIKE THE MODEL SPREAD ON WEDNESDAY...THE ECMWF REMAINS THE FARTHEST SOUTH WHILE THE NAM AND ESPECIALLY THE GFS AND CANADIAN ARE FARTHER NORTH. THE LATTER 3 MODELS PRODUCE MUCH MORE CONVECTION AND PRECIPITATION FOR US WHILE THE ECMWF IS NEARLY DRY WITH ITS CONVECTION SOUTH OF THE FORECAST AREA. GIVEN THE NAM/GFS/CANADIAN BIAS OVERALL THIS YEAR TO BE TOO FAR NORTH...THE NORTHWEST FLOW PATTERN AND CONVECTIVE OUTFLOWS HOLDING UP THE FRONT...FEEL A MORE SOUTHERN TRACK OF THE ECMWF IS MORE LIKELY TO OCCUR. THEREFORE...PRECIPITATION CHANCES FOR THE MOST PART ARE IN THE 20-50 RANGE. HARD TO GET TOO EXCITED ABOUT ANY SEVERE CHANCES GIVEN THIS SPREAD IN CONVECTION LOCATION AS WELL. 3. BEYOND THURSDAY THROUGH EARLY NEXT WEEK. MODELS ARE DRIVING MULTIPLE SHORTWAVES DOWN ACROSS THE FORECAST AREA. PROBLEM IS THE MOISTURE AS THE MAIN FRONTAL BOUNDARY AFTER THE SHORTWAVES PASS ON THURSDAY GETS SHUNTED DOWN TO THE GULF COAST. NEW 22.12Z ECMWF REALLY HAS BACKED OFF ON PRECIPITATION AND DEPICTS MONDAY AS THE ONLY TIME PERIOD OF SEEING SOME PRECIPITATION. MEANWHILE...THE 22.12Z GFS/CANADIAN BOTH WANT TO KEEP THE AREA GETTING HIT BY SPORADIC SHOWERS/STORMS WITH THE SHORTWAVES. IT APPEARS THESE MODELS MAY BE PRODUCING TOO MUCH EVAPOTRANSPIRATION TO BOOST UP BOUNDARY LAYER MOISTURE. THEREFORE...CHANCES OF PRECIPITATION FOR THE REST OF THE FORECAST HAVE BEEN TRENDED DOWNWARD. LATER FORECASTS SHOULD BE ABLE TO GIVE SOME DRY PERIODS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 615 PM CDT MON JUN 22 2015 WEAK HIGH PRESSURE BUILDS ACROSS THE REGION TONIGHT...AND WILL BE THE MAIN WEATHER INFLUENCE THROUGH TUE. LOOK FOR VFR CONDITIONS AS A RESULT WITH SKC/SCT SKIES. WINDS WILL STAY WEST/NORTHWESTERLY TONIGHT-TUE...BECOMING MORE LIGHT AND SOUTHERLY TUE EVENING. && .HYDROLOGY... ISSUED AT 247 PM CDT MON JUN 22 2015 THE STORMS FROM THIS MORNING HIT MUCH OF THE UPPER IOWA RIVER BASIN AND NORTHERN PORTION OF THE CEDAR RIVER BASIN PRETTY HARD. COMBINATION OF RADAR AND OBSERVATIONS SHOWED ANYWHERE FROM 3 TO 5 INCHES. THE NORTHERN END OF THE TURKEY AND SOUTHERN END OF THE KICKAPOO ALSO GOT HIT WITH 1 TO 2 INCHES OF RAIN. AS A RESULT...THESE RIVERS ARE RISING WITH SOME FLOOD WARNINGS OUT. SINCE THEY ARE QUICK RESPONDING...MOST SHOULD DROP BELOW FLOOD STAGE IN THE NEXT 1 TO 2 DAYS...ESPECIALLY GIVEN LITTLE OR NO ADDITIONAL RAINFALL EXPECTED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION....RIECK HYDROLOGY...AJ
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1131 AM CDT SUN JUN 21 2015 .UPDATE... WEAK HIGH PRESSURE SHOULD BRING A PLEASANT AFTERNOON ACROSS THE AREA. SOME DIURNAL CUMULUS DEVELOPMENT SEEN IN THE NORTHERN AND CENTRAL PORTIONS OF THE AREA...WHICH SHOULD EVENTUALLY MIX OUT AS DEW POINTS DROP WITH PEAK HEATING. THIS SHOULD PREVENT ANY SHOWER DEVELOPMENT WITH PASSING 500 MB VORTICITY MAXIMUM. SOME MIDDLE TO HIGH CLOUDS SHOULD MOVE EAST THROUGH THE AREA AS WELL. LAKE BREEZE IS EXPECTED NEAR LAKE MICHIGAN AS WELL...WHICH SHOULD BRING TEMPERATURES BACK INTO THE 70S. RAISED HIGHS NEAR THE LAKE...WITH OFFSHORE WINDS LINGERING UNTIL LAKE BREEZE KICKS IN. HIGHS SHOULD REACH THE LOWER TO MID 80S INLAND. && .AVIATION/18Z TAFS/... WEAK HIGH PRESSURE WILL KEEP VFR CONDITIONS THIS AFTERNOON AND EARLY EVENING ACROSS TAF SITES. WEST NORTHWEST WINDS ARE EXPECTED AT MADISON AND WAUKESHA...WITH WINDS BECOMING EAST TO SOUTHEAST AT MILWAUKEE AND KENOSHA WITH LAKE BREEZE. DIURNAL CUMULUS SHOULD LINGER FOR A TIME THIS AFTERNOON BEFORE DIMINISHING. SOME MIDDLE TO HIGH CLOUDS ARE EXPECTED AS WELL. WINDS WILL BECOME SOUTH TO SOUTHEAST TONIGHT...WITH SOME LIGHT FOG POSSIBLE. SOUTH WINDS WILL BECOME GUSTY MONDAY...THEN VEER SOUTHWEST LATER IN THE DAY. THERE SHOULD BE A THUNDERSTORM COMPLEX MOVING THROUGH THE AREA DURING THE MORNING HOURS...WITH STRONG WINDS AND LARGE HAIL POSSIBLE. IFR VISIBILITIES AND MVFR CEILINGS ARE POSSIBLE DURING THIS TIME WITH ANY STORMS. STORM CHANCES LATER IN THE DAY WITH THE COLD FRONT WILL DEPEND ON IF ENOUGH SUNSHINE OCCURS AFTER MORNING STORMS MOVE OUT. SEVERE STORMS ARE POSSIBLE IF THEY DO OCCUR MONDAY AFTERNOON...WITH IFR VISIBILITIES AND MVFR CEILINGS POSSIBLE. && .MARINE... KEPT PATCHY FOG OVER THE NORTHERN MOST MARINE ZONE...NORTH OF PORT WASHINGTON...PER AREA WEB CAMERAS. REST OF THE NEARSHORE AREA LOOKS FAIRLY FREE OF ANY FOG. COOLER AREAS TO THE WELL NORTH OF SHEBOYGAN AND OVER THE OPEN WATERS WILL HAVE DENSE FOG INTO MONDAY. KEPT PATCHY FOG TONIGHT...WITH LIGHT WINDS AND SIMILAR DEW POINTS TO LAST NIGHT REMAINING OVER THE WATERS. A TIGHT PRESSURE GRADIENT MONDAY INTO MONDAY NIGHT...WITH PASSING LOW PRESSURE TO THE NORTH...SHOULD BRING INCREASING SOUTH WINDS MONDAY...BECOMING SOUTHWEST LATER IN THE DAY. THESE WINDS WILL VEER NORTHWEST MONDAY NIGHT...BEFORE WEAKENING ON TUESDAY. GUSTS OF 25 TO 30 KNOTS ARE POSSIBLE. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR THIS PERIOD. && .PREV DISCUSSION... /ISSUED 351 AM CDT SUN JUN 21 2015/ TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. SOME PATCHY FOG DEVELOPED IN THE FAR SOUTH CENTRAL AND SOUTHWEST THAT SAW THE BETTER RAINFALL ON SATURDAY. WEB CAMS AND OBS CURRENTLY SHOW CONDITIONS ARE NOT WIDESPREAD ENOUGH FOR AN ADVISORY...PROBABLY DUE TO SLOWLY RETREATING CIRRUS SHIELD. WILL CONTINUE TO HANDLE WITH SPS AND MONITOR CLOSELY. OTHERWISE LOOKING FOR QUIET WEATHER TODAY INTO THIS EVENING AS WEAK HIGH PRESSURE MOVES ACROSS REGION. SHOULD SEE ANY LOW STRATUS/FOG MIX OUT BY MID TO LATE MORNING WITH ENOUGH SUN AND 925 MB TEMPS SUPPORTING HIGHS IN THE LOW 80S INLAND...WITH UPPER 60S TO MID 70S CLOSER TO THE LAKE. CYCLOGENESIS IN THE CENTRAL PLAINS AHEAD OF POTENT SHORT WAVE...WITH PRECIPITATION DEVELOPING IN THE WARM ADVECTION REGIME...TRIGGERING A THUNDERSTORM COMPLEX OVER SOUTH DAKOTA. WILL BRING IN CHANCE POPS INTO THE WEST BETWEEN 09Z AND 12Z WITH CONVERGENCE ALONG LEADING EDGE OF STRONGER LOW-LEVEL JET. MONDAY INTO MONDAY EVENING...FORECAST CONFIDENCE IS MEDIUM. ZONAL MID LEVEL FLOW WILL START TO BUCKLE AS A SHORT WAVE TROUGH PROPAGATES EAST ALONG THE US/CANADIAN BORDER. WHILE MUCH OF THE MID LEVEL LIFT FROM THIS FEATURE WILL STAY NORTH OF THE REGION...IT WILL CAUSE A TIGHTENING OF MID LEVEL HEIGHTS AND INCREASE WIND SPEEDS INTO THE 70-80KT RANGE BY AFTERNOON/EVENING. IT WILL ALSO AID IN THE DEVELOPMENT OF A SURFACE LOW OVER THE NORTHERN PLAINS EARLY ON MONDAY WHICH WILL HELP TO INCREASE LOW LEVEL SOUTHERLY FLOW INTO THE REGION. A STRENGTHENING LOW LEVEL JET WILL NOSE UP INTO EASTERN MINNESOTA/WESTERN WISCONSIN AROUND DAYBREAK MONDAY BEFORE SHIFTING EASTWARD INTO THE GREAT LAKES THROUGH THE MORNING. THE FORCING ALONG THE NOSE OF THE LLJ SHOULD BE ENOUGH TO MAINTAIN CONVECTION ACROSS EASTERN MINNESOTA ON INTO WISCONSIN THROUGH THE REST OF THE MORNING. EXACTLY WHERE THIS CONVECTION TRACKS IS STILL A BIT UNCERTAIN...BUT THE CENTRAL TO NORTHERN PORTIONS OF WISCONSIN SEEMS TO BE A CONVERGENCE POINT IN THE 21.00Z MODELS. ELEVATED INSTABILITY WILL BE ON THE INCREASE AND FEEDING INTO THESE MORNING STORMS...SO WILL HAVE TO WATCH FOR THE POTENTIAL OF SOME SEVERE WEATHER IN THE MORNING HOURS AS THIS FEATURE MOVES THROUGH. LARGE HAIL AND DAMAGING WINDS ARE THE MAIN CONCERNS WITH THIS FIRST WAVE OF STORMS IF THEY ENTER THE REGION. THE FOCUS THEN SHIFTS TO THE AFTERNOON AND THE SECOND ROUND OF CONVECTION WHICH IS EXPECTED TO INITIATE AHEAD OF THE COLD FRONT. THE 21.00Z NAM/GFS/ECMWF/GEM ALL ARE CONSISTENT WITH TAKING THE SURFACE LOW NORTH OF THE REGION THROUGH THE UP OF MICHIGAN WITH A TRAILING COLD FRONT ANGLING DOWN TOWARD EASTERN IOWA BY 00Z TUESDAY. THIS SHOULD FIRMLY PUT SOUTHEASTERN WISCONSIN INTO THE WARM SECTOR THROUGH MUCH OF THE AFTERNOON. A WARM LAYER AROUND 700MB SHOULD KEEP SOUTHERN WISCONSIN CAPPED OFF THROUGH THE EARLY PORTION OF THE AFTERNOON AND ALLOW FOR THE ENVIRONMENT TO BECOME HIGHLY UNSTABLE AS SURFACE TEMPERATURES CLIMB INTO THE 80S AND DEW POINTS RISE TO THE LOW 70S. SB/MLCAPE SHOULD APPROACH 4000 J/KG BASED ON MODIFIED 21.00Z NAM/GFS SOUNDINGS WHICH ARE STILL PRODUCING TOO HIGH OF SFC DEW POINTS OF AROUND 77-80F. THIS CAP SHOULD SHIFT TO THE EAST BY MID AFTERNOON AND ALLOW FOR CONVECTION TO INITIATE AHEAD OF THE FRONT. 0-6KM SHEAR LOOKS VERY FAVORABLE FOR ORGANIZING CONVECTION...BUT DOES LOOK FAIRLY UNIDIRECTIONAL WITH LITTLE VEERING FROM THE SOUTHWEST TO WEST SURFACE WINDS GOING UP TO WESTERLY MID LEVEL WINDS. THE ONLY SOURCE FOR SOME BETTER LOW LEVEL SOUTHEASTERLIES WOULD BE IF THERE IS ANY LEFTOVER OUTFLOW BOUNDARIES FROM THE MORNING CONVECTION THOUGH THE INCREASING SOUTHERLY LOW LEVEL FLOW MAY WIPE ANY OF THIS OUT. THE 0-6KM SHEAR VECTOR DOES ANGLE ABOUT 45 DEGREES OFF OF THE BOUNDARY...SO SOME OF THE INITIAL CONVECTION COULD START OUT AS DISCRETE SUPERCELLS BEFORE MERGING INTO A SQUALL LINE AS THE FRONT SWINGS THROUGH. 0-1KM WIND SHEAR DOES LOOK STRONG ENOUGH TO SUPPORT TORNADO DEVELOPMENT...BUT SEEMS TO BE ON THE DECLINE THROUGH THE AFTERNOON AS THE LLJ SHIFTS EAST. OVERALL...QUITE A BIT OF FAVORABLE CONDITIONS IN PLACE FOR A SEVERE WEATHER OUTBREAK...BUT ALSO STILL SOME QUESTIONS REGARDING STORM EVOLUTION...HOW FAST CONVECTION INITIATES ONCE THE CAP SHIFTS EAST...AND HOW BIG IS THE TORNADO THREAT. TUESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS LOW. ZONAL FLOW ALOFT LINGERS THROUGH THE REST OF THE WEEK...BUT STARTS TO BECOME MORE NORTHWESTERLY AS THE WEEK PROGRESSES. MUCH OF THE PRECIPITATION CHANCES WILL BE TIED TO ANY QUICK MOVING SHORT WAVE TROUGHS THAT PROPAGATE THROUGH THE FLOW. THE MAIN SURFACE WARM/STATIONARY FRONT LOOKS LIKE IT WILL STAY TO THE SOUTH OF THE REGION...BUT COULD LIFT NORTH WITH ANY SYSTEM THAT MOVES IN. TRYING TO TIME DOWN ANY OF THESE SYSTEM IS TOUGH AT THIS POINT...THOUGH THE 21.00Z GFS/ECMWF/GEM DO TRY AND DEVELOP SOME CONVECTION ALONG THE FRONT TUESDAY NIGHT INTO THURSDAY. TEMPERATURES SHOULD STAY SEASONAL WITH THE REGION STAYING MAINLY ON THE COOL SIDE OF THE BOUNDARY THROUGH MUCH OF THE WEEK. AVIATION/12Z TAFS/... SEEING PATCHY/AREAS OF FOG AND IFR CIGS IN FAR SOUTH CENTRAL/SOUTHWEST LOCATIONS THAT HAVE ABUNDANT LOW-LEVEL MOISTURE FROM SATURDAY RAINS. LOWER CLOUD COVER BEING REVEALED ON SATELLITE FOG PRODUCT BELOW SLOWLY DEPARTING CIRRUS SHIELD SHOWS HOW PATCHY IT CURRENTLY IS. SREF VSBY PROBABILITY FORECASTS HANDLING THE CURRENT SITUATION BETTER THAN THE MORE WIDESPREAD HRRR SO NOT EXPECTING CONDITIONS TO DETERIORATE EVERYWHERE.WILL MONITOR CLOSELY...BUT EXPECT ONLY LOCAL IFR VSBYS/CIGS THAT WILL MIX OUT BY MID MORNING. THEN VFR CONDITIONS THROUGH THE REMAINDER OF THE FORECAST. WARM AIR ADVECTION SHOWERS AND THUNDERSTORMS WILL BEGIN TO MOVE INTO WESTERN FORECAST AREA BETWEEN 09Z AND 12Z MONDAY...WARRANTING NO MORE THAN A PROB30 AT KMSN AND NOTHING EAST UNTIL AFTER 12Z. MARINE... PATCHY FOG IS EXPECTED TO LINGER TONIGHT INTO SUNDAY...WITH DEW POINTS JUST HIGH ENOUGH OVER THE LAKE MICHIGAN WATER TEMPERATURES. NOT EXPECTING ANY DENSE FOG AT THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...WOOD TODAY/TONIGHT AND AVIATION/MARINE...REM MONDAY THROUGH SATURDAY...HALBACH
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
351 AM CDT SUN JUN 21 2015 .TODAY AND TONIGHT...FORECAST CONFIDENCE IS MEDIUM. SOME PATCHY FOG DEVELOPED IN THE FAR SOUTH CENTRAL AND SOUTHWEST THAT SAW THE BETTER RAINFALL ON SATURDAY. WEB CAMS AND OBS CURRENTLY SHOW CONDITIONS ARE NOT WIDESPREAD ENOUGH FOR AN ADVISORY...PROBABLY DUE TO SLOWLY RETREATING CIRRUS SHIELD. WILL CONTINUE TO HANDLE WITH SPS AND MONITOR CLOSELY. OTHERWISE LOOKING FOR QUIET WEATHER TODAY INTO THIS EVENING AS WEAK HIGH PRESSURE MOVES ACROSS REGION. SHOULD SEE ANY LOW STRATUS/FOG MIX OUT BY MID TO LATE MORNING WITH ENOUGH SUN AND 925 MB TEMPS SUPPORTING HIGHS IN THE LOW 80S INLAND...WITH UPPER 60S TO MID 70S CLOSER TO THE LAKE. CYCLOGENESIS IN THE CENTRAL PLAINS AHEAD OF POTENT SHORT WAVE...WITH PRECIPITATION DEVELOPING IN THE WARM ADVECTION REGIME...TRIGGERING A THUNDERSTORM COMPLEX OVER SOUTH DAKOTA. WILL BRING IN CHANCE POPS INTO THE WEST BETWEEN 09Z AND 12Z WITH CONVERGENCE ALONG LEADING EDGE OF STRONGER LOW-LEVEL JET. .MONDAY INTO MONDAY EVENING...FORECAST CONFIDENCE IS MEDIUM. ZONAL MID LEVEL FLOW WILL START TO BUCKLE AS A SHORT WAVE TROUGH PROPAGATES EAST ALONG THE US/CANADIAN BORDER. WHILE MUCH OF THE MID LEVEL LIFT FROM THIS FEATURE WILL STAY NORTH OF THE REGION...IT WILL CAUSE A TIGHTENING OF MID LEVEL HEIGHTS AND INCREASE WIND SPEEDS INTO THE 70-80KT RANGE BY AFTERNOON/EVENING. IT WILL ALSO AID IN THE DEVELOPMENT OF A SURFACE LOW OVER THE NORTHERN PLAINS EARLY ON MONDAY WHICH WILL HELP TO INCREASE LOW LEVEL SOUTHERLY FLOW INTO THE REGION. A STRENGTHENING LOW LEVEL JET WILL NOSE UP INTO EASTERN MINNESOTA/WESTERN WISCONSIN AROUND DAYBREAK MONDAY BEFORE SHIFTING EASTWARD INTO THE GREAT LAKES THROUGH THE MORNING. THE FORCING ALONG THE NOSE OF THE LLJ SHOULD BE ENOUGH TO MAINTAIN CONVECTION ACROSS EASTERN MINNESOTA ON INTO WISCONSIN THROUGH THE REST OF THE MORNING. EXACTLY WHERE THIS CONVECTION TRACKS IS STILL A BIT UNCERTAIN...BUT THE CENTRAL TO NORTHERN PORTIONS OF WISCONSIN SEEMS TO BE A CONVERGENCE POINT IN THE 21.00Z MODELS. ELEVATED INSTABILITY WILL BE ON THE INCREASE AND FEEDING INTO THESE MORNING STORMS...SO WILL HAVE TO WATCH FOR THE POTENTIAL OF SOME SEVERE WEATHER IN THE MORNING HOURS AS THIS FEATURE MOVES THROUGH. LARGE HAIL AND DAMAGING WINDS ARE THE MAIN CONCERNS WITH THIS FIRST WAVE OF STORMS IF THEY ENTER THE REGION. THE FOCUS THEN SHIFTS TO THE AFTERNOON AND THE SECOND ROUND OF CONVECTION WHICH IS EXPECTED TO INITIATE AHEAD OF THE COLD FRONT. THE 21.00Z NAM/GFS/ECMWF/GEM ALL ARE CONSISTENT WITH TAKING THE SURFACE LOW NORTH OF THE REGION THROUGH THE UP OF MICHIGAN WITH A TRAILING COLD FRONT ANGLING DOWN TOWARD EASTERN IOWA BY 00Z TUESDAY. THIS SHOULD FIRMLY PUT SOUTHEASTERN WISCONSIN INTO THE WARM SECTOR THROUGH MUCH OF THE AFTERNOON. A WARM LAYER AROUND 700MB SHOULD KEEP SOUTHERN WISCONSIN CAPPED OFF THROUGH THE EARLY PORTION OF THE AFTERNOON AND ALLOW FOR THE ENVIRONMENT TO BECOME HIGHLY UNSTABLE AS SURFACE TEMPERATURES CLIMB INTO THE 80S AND DEW POINTS RISE TO THE LOW 70S. SB/MLCAPE SHOULD APPROACH 4000 J/KG BASED ON MODIFIED 21.00Z NAM/GFS SOUNDINGS WHICH ARE STILL PRODUCING TOO HIGH OF SFC DEW POINTS OF AROUND 77-80F. THIS CAP SHOULD SHIFT TO THE EAST BY MID AFTERNOON AND ALLOW FOR CONVECTION TO INITIATE AHEAD OF THE FRONT. 0-6KM SHEAR LOOKS VERY FAVORABLE FOR ORGANIZING CONVECTION...BUT DOES LOOK FAIRLY UNIDIRECTIONAL WITH LITTLE VEERING FROM THE SOUTHWEST TO WEST SURFACE WINDS GOING UP TO WESTERLY MID LEVEL WINDS. THE ONLY SOURCE FOR SOME BETTER LOW LEVEL SOUTHEASTERLIES WOULD BE IF THERE IS ANY LEFTOVER OUTFLOW BOUNDARIES FROM THE MORNING CONVECTION THOUGH THE INCREASING SOUTHERLY LOW LEVEL FLOW MAY WIPE ANY OF THIS OUT. THE 0-6KM SHEAR VECTOR DOES ANGLE ABOUT 45 DEGREES OFF OF THE BOUNDARY...SO SOME OF THE INITIAL CONVECTION COULD START OUT AS DISCRETE SUPERCELLS BEFORE MERGING INTO A SQUALL LINE AS THE FRONT SWINGS THROUGH. 0-1KM WIND SHEAR DOES LOOK STRONG ENOUGH TO SUPPORT TORNADO DEVELOPMENT...BUT SEEMS TO BE ON THE DECLINE THROUGH THE AFTERNOON AS THE LLJ SHIFTS EAST. OVERALL...QUITE A BIT OF FAVORABLE CONDITIONS IN PLACE FOR A SEVERE WEATHER OUTBREAK...BUT ALSO STILL SOME QUESTIONS REGARDING STORM EVOLUTION...HOW FAST CONVECTION INITIATES ONCE THE CAP SHIFTS EAST...AND HOW BIG IS THE TORNADO THREAT. TUESDAY THROUGH SATURDAY...FORECAST CONFIDENCE IS LOW. ZONAL FLOW ALOFT LINGERS THROUGH THE REST OF THE WEEK...BUT STARTS TO BECOME MORE NORTHWESTERLY AS THE WEEK PROGRESSES. MUCH OF THE PRECIPITATION CHANCES WILL BE TIED TO ANY QUICK MOVING SHORT WAVE TROUGHS THAT PROPAGATE THROUGH THE FLOW. THE MAIN SURFACE WARM/STATIONARY FRONT LOOKS LIKE IT WILL STAY TO THE SOUTH OF THE REGION...BUT COULD LIFT NORTH WITH ANY SYSTEM THAT MOVES IN. TRYING TO TIME DOWN ANY OF THESE SYSTEM IS TOUGH AT THIS POINT...THOUGH THE 21.00Z GFS/ECMWF/GEM DO TRY AND DEVELOP SOME CONVECTION ALONG THE FRONT TUESDAY NIGHT INTO THURSDAY. TEMPERATURES SHOULD STAY SEASONAL WITH THE REGION STAYING MAINLY ON THE COOL SIDE OF THE BOUNDARY THROUGH MUCH OF THE WEEK. && .AVIATION/12Z TAFS/... SEEING PATCHY/AREAS OF FOG AND IFR CIGS IN FAR SOUTH CENTRAL/SOUTHWEST LOCATIONS THAT HAVE ABUNDANT LOW-LEVEL MOISTURE FROM SATURDAY RAINS. LOWER CLOUD COVER BEING REVEALED ON SATELLITE FOG PRODUCT BELOW SLOWLY DEPARTING CIRRUS SHIELD SHOWS HOW PATCHY IT CURRENTLY IS. SREF VSBY PROBABILITY FORECASTS HANDLING THE CURRENT SITUATION BETTER THAN THE MORE WIDESPREAD HRRR SO NOT EXPECTING CONDITIONS TO DETERIORATE EVERYWHERE.WILL MONITOR CLOSELY...BUT EXPECT ONLY LOCAL IFR VSBYS/CIGS THAT WILL MIX OUT BY MID MORNING. THEN VFR CONDITIONS THROUGH THE REMAINDER OF THE FORECAST. WARM AIR ADVECTION SHOWERS AND THUNDERSTORMS WILL BEGIN TO MOVE INTO WESTERN FORECAST AREA BETWEEN 09Z AND 12Z MONDAY...WARRANTING NO MORE THAN A PROB30 AT KMSN AND NOTHING EAST UNTIL AFTER 12Z. && .MARINE... PATCHY FOG IS EXPECTED TO LINGER TONIGHT INTO SUNDAY...WITH DEW POINTS JUST HIGH ENOUGH OVER THE LAKE MICHIGAN WATER TEMPERATURES. NOT EXPECTING ANY DENSE FOG AT THIS TIME. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM MONDAY THROUGH SATURDAY...HALBACH
AREA FORECAST DISCUSSION...UPDATED
NWS MELBOURNE FL
430 AM EDT TUE JUN 23 2015 .DISCUSSION... ...SCATTERED STORMS EXPECTED THIS WEEK AND INTO THE UPCOMING WEEKEND... CURRENTLY...CONVECTION HAS DISSIPATED ACROSS NRN LAKE AND INLAND VOLUSIA COUNTIES WHERE SOME SHOWERS AND THUNDERSTORMS DEVELOPED AFTER MIDNIGHT. LEESBURG AIRPORT RECEIVED .46 INCHES OF RAIN. FAVORABLE LOW LVL CONVERGENCE...DEEPER MOISTURE AND SOME MID LVL VORTICITY ANALYZED IN THE 00Z NAM/GFS MODELS AIDED NOCTURNAL CONVECTION AGAIN OVERNIGHT. TODAY...00Z NAM/GFS MODELS ARE INSISTENT IN LIFTING DEEPER MOISTURE WITH PWATS FROM 1.9-2.1 INCHES ACROSS OUR SRN ZONES THIS MORNING AND TOWARD THE ORLANDO METRO AND SRN LATE COUNTY BY MID TO LATE AFTERNOON. A SWATH OF DRIER AIR WITH PWAT DOWN TO 1.43 INCHES AT THE CAPE AT 00Z LAST EVENING SHOULD BE ADVECTED NWD OFFSHORE FROM THE VOLUSIA COUNTY COAST AROUND THE ATLC RIDGE. WILL FCST 40-50 POPS FOR THE INTERIOR...30-40 PCT THE COASTAL COUNTIES WITH LOWER RAIN CHANCES ALONG THE IMMEDIATE COAST. HRRR MODEL INDICATES BETTER COVERAGE OF SHOWERS/THUNDERSTORMS ALONG THE EAST COAST BREEZE BOUNDARY TODAY FROM BREVARD TO THE TREASURE COAST WITH THE HIGHER MOISTURE LEVELS. SPC HAS ALSO OUTLOOKED THE INTERIOR WITH A MARGINAL RISK FOR SEVERE WEATHER WITH THE RISK OF A WET MICROBURST WITH THE STRONGEST STORMS FROM THE MID TO LATE AFTERNOON INTO THE EVENING. HIGHS TODAY ARE EXPECTED TO RANGE FROM THE LOWER 90S S CSTL TO THE MID 90S OVER THE INTERIOR. TONIGHT...EXPECT SCATTERED STORMS FOR NRN INTERIOR AREAS IN THE EVENING WITH A FEW STRONG STORMS POSSIBLE. KEPT A SLIGHT CHANCE FOR STORMS TO DEVELOP BACK TOWARD THE VOLUSIA/BREVARD COUNTY COAST IN THE EVENING WITH GFS INDICATING VEERING LOW LVL FLOW AND DEEPER MOISTURE ENCROACHING ON AREAS WHERE LINGERING STABILITY MAY BE PRESENT. LOWS WILL MAINLY BE IN THE MID TO UPPER 70S. WED-WED NIGHT... ZONAL H30-H20 JET OVER THE NRN TIER STATES WILL PUSH A STORM SYSTEM FROM THE GREAT LAKES INTO ERN CANADA. SRN EXTENSION OF ITS TRAILING TROF AXIS WILL WORK ITS WAY INTO A WEAKNESS IN THE H100-H70 ATLC RIDGE OVER GA/FL. THIS WILL EFFECTIVELY SPLIT THE RIDGE IN TWO WITH ITS WRN PORTION BCMG AN INDEPENDENT ANTICYCLONE CENTERED NEAR THE ARKLATEX WHILE ITS MAIN BODY RETREATS E OF THE BAHAMA BANK. THE RESULTING COL WILL COLLAPSE THE DEEP LYR FLOW OVER THE FL PENINSULA. WITH SUCH WEAK FLOW IN PLACE...ANY STORMS THAT DEVELOP WILL BE SLOW MOVERS AT BEST. MODERATE MID LVL INSTABILITY WILL COME FROM A BAND OF ENHANCED VORTICITY OVER THE FL PANHANDLE THAT WILL WORK ITS WAY SWD WITH THE APPROACHING TROF. H30-H20 ANTICYCLONE OVER N FL WILL PRODUCE WEAK UPR LVL EVACUATION...BUT ALSO WILL ALLOW SIG CONVECTIVE DEBRIS CLOUDS TO REMAIN TRAPPED OVER THE FL PENINSULA. INDEED...WHILE MODEL SOUNDINGS INDICATE PWAT VALUES RECOVERING TO ARND 2.0"...MUCH OF IT IS TRAPPED IN AN H40-H20 SATURATION LYR. STAGE IS SET FOR ANOTHER DAY OF PULSE CONVECTION. H70/H50 RUNNING 8C/-8C RESPECTIVELY...YIELDING RESPECTABLE LAPSE RATE OF 6.0-6.5C/KM THRU THE LYR. MODEL SOUNDINGS TO INDICATE A FAIR AMOUNT OF DRY AIR THRU THE H85-H50 LYRS...RAISING THE POTENTIAL FOR STRONG TO SEVERE DOWNBURST WINDS. DEBRIS CLOUDS MAY HAMPER SFC HEATING SOMEWHAT...AND WEAK STEERING FLOW WILL KEEP THE EAST/WEST COAST SEA BREEZES FROM MAKING RAPID INLAND PROGRESS. GFS MOS POPS APPEAR A LITTLE HIGH GIVEN THESE INHIBITORS...BUT FOCUS FOR DIURNAL CONVECTION WILL BE OVER THE INTERIOR COUNTIES. MAX TEMPS AGAIN IN THE L/M90S AS THE STATIC AIR MASS OVERHEAD WILL HEAT UP QUITE EFFICIENTLY...MIN TEMPS IN THE L/M70S...NEAR THEIR RESPECTIVE DEWPOINTS. THU-THU NIGHT... TROF OVER THE ERN SEABOARD WILL DAMPEN OUT AS ITS PARENT LOW MOVES INTO THE CANADIAN MARITIMES. ATLC RIDGE AXIS WILL REBUILD ITSELF OVER THE FL PENINSULA...RESULTING IN SLIGHTLY STRONGER E/SERLY FLOW THRU THE H100-H50 LYR. FOCUS FOR DIURNAL PRECIP WILL SHIFT BACK TO THE W FL PENINSULA WITH LOW PROSPECT FOR RAINFALL ALONG THE ERN COASTAL COUNTIES. CONTINUED HOT WITH MAX TEMPS IN THE L/M90S...MINS L/M70S. FRI-MON... PATTERN CHANGE IN THE NRN JET AS IT SHIFT FROM A ZONAL TO MORE MERIDIONAL ORIENTATION OVER THE ERN CONUS...DEVELOPING A HI AMP MID/UPR LVL SHORT WAVE IN THE PROCESS. BOTH GFS/ECMWF MODELS RESPOND BY DVLPG A LARGE AREA OF LOW PRES OVER THE MID AND DEEP SOUTH THAT WILL SUPPRESS THE ATLC RIDGE AXIS INTO S FL THRU EARLY NEXT WEEK. THE RESULTING H100-H70 FLOW WILL SHIFT TO THE S ON FRI...THEN TO THE SW ON SAT...RESULTING IN HIGHER DIURNAL POPS OVER THE E FL COAST. HOWEVER...NEITHER MODEL IS PARTICULARLY GUNG-HO WITH POPS AS BOTH INDICATE LOW RH AIR OVER THE WRN CARIB WORKING ITS WAY NWD AND BCMG ENTRAINED IN THE DVLPG SWRLY FLOW. PRECIP CHANCES GENERALLY AOB 50PCT WITH TEMPS RETURNING NEAR OR SLIGHTLY ABV AVG...MAXES U80SL90S AND MINS L/M70S. && .AVIATION...SHOULD SEE EARLIER START TO CONVECTIVE DEVELOPMENT TODAY INITIALLY ALONG THE SEA BREEZE FROM KSUA-KMLB...AND THEN SCATTERED STORMS DEVELOPING NORTHWARD TOWARD INTERIOR TERMINALS IN THE MID TO LATE AFTERNOON. ISOLD TSRA MAY LINGER INTO THE EVENING PAST 01Z...MAINLY NORTH OF A KISM-KTIX LINE BUT PROBS TOO LOW TO MENTION. && .MARINE... SEAS REMAIN RATHER FLAT AT 1-2 FT NEAR SHORE AND 2 FT AT BUOY 41009 EARLY THIS MORNING. S/SSW WINDS THIS MORNING WILL VEER TO THE SE THIS AFTERNOON TO AROUND 10 KNOTS...THEN WINDS FROM THE SE/S WILL BECOME SSW/SW TONIGHT. WILL KEEP SEAS AROUND 2 FT NEAR SHORE AND PERHAPS UP TO 2-3 FT FOR THE NRN OFFSHORE WATERS LATE TONIGHT. WED-SAT...GENERALLY FAVORABLE BOATING CONDITIONS AS THE ATLC RIDGE AXIS MEANDERS BTWN THE CENTRAL AND SRN FL PENINSULA WHILE A SERIES OF LOW PRESSURE SYSTEMS WORK THEIR WAY ACRS THE ERN CONUS. GENTLE TO MODERATE S/SW BREEZE THRU THE END OF THE WEEK...SEAS 2-3FT. INCREASING CHANCES FOR OFFSHORE MOVING TSRAS IN THE AFTN/EVNG AS THE WEEKEND APPROACHES. && .CLIMATE... DAYTONA BEACH TIED THEIR RECORD HIGH OF 96 DEGREES YESTERDAY SET BACK IN 2009. RECORD HIGHS TODAY LOOK OUT OF REACH: RECORDS HIGHS FOR TODAY/JUNE 23RD... DAYTONA BEACH 100 IN 1944 ORLANDO 99 IN 1939 MELBOURNE 96 IN 1998 VERO BEACH 94 IN 2009 HIGH MINIMUM TEMPERATURES RECORDS TODAY WHICH COULD BE TIED OR BROKEN. DAYTONA BEACH 77 IN 1972 VERO BEACH 79 IN 2010 && .PRELIMINARY POINT TEMPS/POPS... DAB 93 76 92 75 / 30 20 40 10 MCO 94 76 95 75 / 50 30 50 20 MLB 91 75 89 74 / 30 10 40 10 VRB 91 75 90 74 / 30 10 30 10 LEE 96 78 95 77 / 40 40 50 20 SFB 96 77 94 76 / 40 20 50 20 ORL 95 77 94 76 / 40 30 50 20 FPR 91 74 90 73 / 30 10 30 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM/AVIATION...VOLKMER LONG TERM/IMPACT WX....BRAGAW
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
408 AM EDT TUE JUN 23 2015 .DISCUSSION... ...SCATTERED STORMS EXPECTED THIS WEEK AND INTO THE UPCOMING WEEKEND... CURRENTLY...CONVECTION HAS DISSIPATED ACROSS NRN LAKE AND INLAND VOLUSIA COUNTIES WHERE SOME SHOWERS AND THUNDERSTORMS DEVELOPED AFTER MIDNIGHT. LEESBURG AIRPORT RECEIVED .46 INCHES OF RAIN. FAVORABLE LOW LVL CONVERGENCE...DEEPER MOISTURE AND SOME MID LVL VORTICITY ANALYZED IN THE 00Z NAM/GFS MODELS AIDED NOCTURNAL CONVECTION AGAIN OVERNIGHT. TODAY...00Z NAM/GFS MODELS ARE INSISTENT IN LIFTING DEEPER MOISTURE WITH PWATS FROM 1.9-2.1 INCHES ACROSS OUR SRN ZONES THIS MORNING AND TOWARD THE ORLANDO METRO AND SRN LATE COUNTY BY MID TO LATE AFTERNOON. A SWATH OF DRIER AIR WITH PWAT DOWN TO 1.43 INCHES AT THE CAPE AT 00Z LAST EVENING SHOULD BE ADVECTED NWD OFFSHORE FROM THE VOLUSIA COUNTY COAST AROUND THE ATLC RIDGE. WILL FCST 40-50 POPS FOR THE INTERIOR...30-40 PCT THE COASTAL COUNTIES WITH LOWER RAIN CHANCES ALONG THE IMMEDIATE COAST. HRRR MODEL INDICATES BETTER COVERAGE OF SHOWERS/THUNDERSTORMS ALONG THE EAST COAST BREEZE BOUNDARY TODAY FROM BREVARD TO THE TREASURE COAST WITH THE HIGHER MOISTURE LEVELS. SPC HAS ALSO OUTLOOKED THE INTERIOR WITH A MARGINAL RISK FOR SEVERE WEATHER WITH THE RISK OF A WET MICROBURST WITH THE STRONGEST STORMS FROM THE MID TO LATE AFTERNOON INTO THE EVENING. HIGHS TODAY ARE EXPECTED TO RANGE FROM THE LOWER 90S S CSTL TO THE MID 90S OVER THE INTERIOR. TONIGHT...EXPECT SCATTERED STORMS FOR NRN INTERIOR AREAS IN THE EVENING WITH A FEW STRONG STORMS POSSIBLE. KEPT A SLIGHT CHANCE FOR STORMS TO DEVELOP BACK TOWARD THE VOLUSIA/BREVARD COUNTY COAST IN THE EVENING WITH GFS INDICATING VEERING LOW LVL FLOW AND DEEPER MOISTURE ENCROACHING ON AREAS WHERE LINGERING STABILITY MAY BE PRESENT. LOWS WILL MAINLY BE IN THE MID TO UPPER 70S. WED-WED NIGHT... ZONAL H30-H20 JET OVER THE NRN TIER STATES WILL PUSH A STORM SYSTEM FROM THE GREAT LAKES INTO ERN CANADA. SRN EXTENSION OF ITS TRAILING TROF AXIS WILL WORK ITS WAY INTO A WEAKNESS IN THE H100-H70 ATLC RIDGE OVER GA/FL. THIS WILL EFFECTIVELY SPLIT THE RIDGE IN TWO WITH ITS WRN PORTION BCMG AN INDEPENDENT ANTICYCLONE CENTERED NEAR THE ARKLATEX WHILE ITS MAIN BODY RETREATS E OF THE BAHAMA BANK. THE RESULTING COL WILL COLLAPSE THE DEEP LYR FLOW OVER THE FL PENINSULA. WITH SUCH WEAK FLOW IN PLACE...ANY STORMS THAT DEVELOP WILL BE SLOW MOVERS AT BEST. MODERATE MID LVL INSTABILITY WILL COME FROM A BAND OF ENHANCED VORTICITY OVER THE FL PANHANDLE THAT WILL WORK ITS WAY SWD WITH THE APPROACHING TROF. H30-H20 ANTICYCLONE OVER N FL WILL PRODUCE WEAK UPR LVL EVACUATION...BUT ALSO WILL ALLOW SIG CONVECTIVE DEBRIS CLOUDS TO REMAIN TRAPPED OVER THE FL PENINSULA. INDEED...WHILE MODEL SOUNDINGS INDICATE PWAT VALUES RECOVERING TO ARND 2.0"...MUCH OF IT IS TRAPPED IN AN H40-H20 SATURATION LYR. STAGE IS SET FOR ANOTHER DAY OF PULSE CONVECTION. H70/H50 RUNNING 8C/-8C RESPECTIVELY...YIELDING RESPECTABLE LAPSE RATE OF 6.0-6.5C/KM THRU THE LYR. MODEL SOUNDINGS TO INDICATE A FAIR AMOUNT OF DRY AIR THRU THE H85-H50 LYRS...RAISING THE POTENTIAL FOR STRONG TO SEVERE DOWNBURST WINDS. DEBRIS CLOUDS MAY HAMPER SFC HEATING SOMEWHAT...AND WEAK STEERING FLOW WILL KEEP THE EAST/WEST COAST SEA BREEZES FROM MAKING RAPID INLAND PROGRESS. GFS MOS POPS APPEAR A LITTLE HIGH GIVEN THESE INHIBITORS...BUT FOCUS FOR DIURNAL CONVECTION WILL BE OVER THE INTERIOR COUNTIES. MAX TEMPS AGAIN IN THE L/M90S AS THE STATIC AIR MASS OVERHEAD WILL HEAT UP QUITE EFFICIENTLY...MIN TEMPS IN THE L/M70S...NEAR THEIR RESPECTIVE DEWPOINTS. THU-THU NIGHT... TROF OVER THE ERN SEABOARD WILL DAMPEN OUT AS ITS PARENT LOW MOVES INTO THE CANADIAN MARITIMES. ATLC RIDGE AXIS WILL REBUILD ITSELF OVER THE FL PENINSULA...RESULTING IN SLIGHTLY STRONGER E/SERLY FLOW THRU THE H100-H50 LYR. FOCUS FOR DIURNAL PRECIP WILL SHIFT BACK TO THE W FL PENINSULA WITH LOW PROSPECT FOR RAINFALL ALONG THE ERN COASTAL COUNTIES. CONTINUED HOT WITH MAX TEMPS IN THE L/M90S...MINS L/M70S. FRI-MON... UPDATE TO FOLLOW. && .AVIATION...SHOULD SEE EARLIER START TO CONVECTIVE DEVELOPMENT TODAY INITIALLY ALONG THE SEA BREEZE FROM KSUA-KMLB...AND THEN SCATTERED STORMS DEVELOPING NORTHWARD TOWARD INTERIOR TERMINALS IN THE MID TO LATE AFTERNOON. ISOLD TSRA MAY LINGER INTO THE EVENING PAST 01Z...MAINLY NORTH OF A KISM-KTIX LINE BUT PROBS TOO LOW TO MENTION. && .MARINE... SEAS REMAIN RATHER FLAT AT 1-2 FT NEAR SHORE AND 2 FT AT BUOY 41009 EARLY THIS MORNING. S/SSW WINDS THIS MORNING WILL VEER TO THE SE THIS AFTERNOON TO AROUND 10 KNOTS...THEN WINDS FROM THE SE/S WILL BECOME SSW/SW TONIGHT. WILL KEEP SEAS AROUND 2 FT NEAR SHORE AND PERHAPS UP TO 2-3 FT FOR THE NRN OFFSHORE WATERS LATE TONIGHT. WED-SAT...GENERALLY FAVORABLE BOATING CONDITIONS AS THE ATLC RIDGE AXIS MEANDERS BTWN THE CENTRAL AND SRN FL PENINSULA WHILE A SERIES OF LOW PRESSURE SYSTEMS WORK THEIR WAY ACRS THE ERN CONUS. GENTLE TO MODERATE S/SW BREEZE THRU THE END OF THE WEEK...SEAS 2-3FT. INCREASING CHANCES FOR OFFSHORE MOVING TSRAS IN THE AFTN/EVNG AS THE WEEKEND APPROACHES. && .CLIMATE... DAYTONA BEACH TIED THEIR RECORD HIGH OF 96 DEGREES YESTERDAY SET BACK IN 2009. RECORD HIGHS TODAY LOOK OUT OF REACH: RECORDS HIGHS FOR TODAY/JUNE 23RD... DAYTONA BEACH 100 IN 1944 ORLANDO 99 IN 1939 MELBOURNE 96 IN 1998 VERO BEACH 94 IN 2009 HIGH MINIMUM TEMPERATURES RECORDS TODAY WHICH COULD BE TIED OR BROKEN. DAYTONA BEACH 77 IN 1972 VERO BEACH 79 IN 2010 && .PRELIMINARY POINT TEMPS/POPS... DAB 93 76 92 75 / 30 20 40 10 MCO 94 76 95 75 / 50 30 50 20 MLB 91 75 89 74 / 30 10 40 10 VRB 91 75 90 74 / 30 10 30 10 LEE 96 78 95 77 / 40 40 50 20 SFB 96 77 94 76 / 40 20 50 20 ORL 95 77 94 76 / 40 30 50 20 FPR 91 74 90 73 / 30 10 30 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ SHORT TERM/AVIATION...VOLKMER LONG TERM/IMPACT WX....BRAGAW
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
431 AM EDT TUE JUN 23 2015 .SYNOPSIS... ABOVE NORMAL TEMPERATURES WILL CONTINUE ACROSS THE REGION THIS WEEK AS THE SUBTROPICAL RIDGE HOLDS ACROSS THE SOUTHERN STATES. THE CHANCE FOR AFTERNOON AND EVENING THUNDERSTORMS SHOULD INCREASE FOR THE WEEKEND AS AN UPPER LEVEL TROUGH BUILDS ACROSS THE EASTERN CONUS. && .NEAR TERM /THROUGH TONIGHT/... MODELS INDICATE A WEAKNESS IN THE UPPER RIDGE STRETCHING ACROSS THE SOUTHERN TIER STATES TODAY AS AN UPPER TROUGH CROSSES THE GREAT LAKES REGION AND NORTHEASTERN STATES. A WEAK SHORTWAVE ACROSS THE UPSTATE THIS MORNING IS ALSO PROGGED TO CROSS THE MIDLANDS THIS AFTERNOON AND EVENING. THE GFS AND ECMWF TRACK THE SHORT WAVE EAST OF THE MIDLANDS AND CSRA BY MID AFTERNOON WHILE THE NAM...RAP AND HRRR MODELS ARE SLOWER. A LEE TROUGH WILL FROM THE MID-ATLANTIC STATES INTO PIEDMONT. STRONG DIABATIC HEATING AND A MOIST AIRMASS WITH PWAT AROUND 1.50 TO 2.00 INCHES WILL CONTRIBUTE TO STEEP 0-3 KM LAPSE RATES AND MODERATE TO STRONG BUOYANCY DEVELOPING AS TEMPS WARM INTO THE 90S. WILL CONTINUE TO INDICATE SCATTERED AFTERNOON/EVENING CONVECTION WITH SLIGHT CHANCE POPS WEST INCREASING TO ABOUT 40 PERCENT EAST. WATER-LOADED DOWNDRAFTS COULD RESULT IN WET MICROBURSTS CAPABLE OF 45-60 MPH WIND GUSTS AND POCKETS OF WIND DAMAGE BEFORE THIS ACTIVITY DIMINISHES DURING THE EARLY EVENING. ONCE AGAIN EXPECT AFTERNOON HIGHS IN THE UPPER 90S TO AROUND 100 DEGREES WITH LOWS TONIGHT IN THE MID 70S. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... THE MAIN UPPER RIDGE CENTER OVER TN/AR WILL BEGIN BUILDING INTO THE CAROLINAS AND GEORGIA WEDNESDAY. A WEAK BACKDOOR COLD FRONT IS FORECAST TO SAG NEAR THE SC/NC BORDER WEDNESDAY. CONVERGENCE ALONG THE FRONT COMBINED WITH A MOIST AND MODERATE TO STRONG INSTABILITY WILL KEEP A CHANCE OF THUNDERSTORMS ACROSS THE REGION. KEPT POPS AROUND 30 PERCENT ON WEDNESDAY AND NEAR 40 PERCENT THURSDAY. . TEMPERATURES WILL CONTINUE THE DAILY TREK TOWARDS THE CENTURY MARK EACH AFTERNOON...WITH OVERNIGHT LOWS ONLY FALLING INTO THE MIDDLE TO UPPER 70S. AFTERNOON HEAT INDEX VALUES RANGE GENERALLY FROM 104 TO 108 EACH DAY. && .LONG TERM /FRIDAY THROUGH MONDAY/... SOME RELIEF FROM THE HEAT SHOULD BE ON THE WAY FOR THE WEEKEND. BY FRIDAY THE MODELS BEGIN TO MOVE THE CENTER OF THE UPPER RIDGE FURTHER OFF TO THE WEST...WHICH WILL THEN AID IN THE DEVELOPMENT OF TROUGHING ALONG THE EASTERN UNITED STATES. BOTH THE GFS AND THE ECMWF ARE IN AGREEMENT WITH THIS PATTERN SHIFT THROUGH THE PERIOD...WITH A RATHER DEEP TROUGH SETTING UP. THIS SHOULD BE A WELCOMED CHANGE TO THE REGION. HIGH TEMPERATURES WILL COOL SLIGHTLY INTO THE LOWER/MIDDLE 90S FOR FRIDAY AND SATURDAY...AND THEN MAYBE JUST AROUND 90 SUNDAY AND MONDAY. WITH THE DEVELOPMENT OF THE UPPER TROUGH...THE REGION SHOULD SEE A BETTER SOUTHWARD PUSH TO ANY COLD FRONTS PUSHING INTO THE REGION. THIS SHOULD HELP WITH AN INCREASE IN THE RAIN CHANCES INTO AND THROUGH THE WEEKEND...WITH COVERAGE BECOMING MORE SCATTERED ACROSS THE REGION. THE CONVECTION SHOULD REMAIN MAINLY BE DIURNALLY INDUCED. && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... VFR CONDITIONS EXPECTED FOR MOST OF THE PERIOD...BRIEF MVFR FORECAST IN FOG AT AGS/OGB. SATELLITE LOOPS THIS MORNING SHOWS SOME MID/HIGH CLOUDS...ESPECIALLY ACROSS THE SRN HALF OF THE STATE. WITH SHALLOW LOW-LEVEL MOISTURE...SOME FOG MAY DEVELOP TOWARD MORNING AT FOG PRONE SITES SUCH AS AGS/OGB. HAVE INCLUDED A BRIEF TEMPO PERIOD FOR BOTH SITES. EXPECT VFR CONDITIONS TO RETURN TO ALL SITES BY 13Z. SCATTERED CUMULUS TO ONCE AGAIN DEVELOP ACROSS THE AREA FROM LATE THIS MORNING INTO THE AFTERNOON HOURS. THUNDERSTORM THREAT APPEARS LOWER BUT STILL COULD AFFECT THE TAF SITES...ESPECIALLY OGB WHERE BEST MOISTURE CONVERGENCE AND INSTABILITY WILL BE LOCATED. WINDS WILL BE FROM THE SOUTHWEST LESS THAN 10 KNOTS. BY TONIGHT...SKIES WILL ONCE AGAIN BECOME MOSTLY CLEAR WITH LIGHT AND VARIABLE WINDS. EXTENDED AVIATION OUTLOOK...NO SIGNIFICANT IMPACTS TO AVIATION EXPECTED THROUGH SATURDAY. && .CLIMATE... RECORDS FROM TUE JUNE 23RD THROUGH THU JUNE 25TH AUGUSTA... JUN 23...104 IN 1944 JUN 24...103 IN 1914 JUN 25...104 IN 1914 COLUMBIA... JUN 23...102 SET IN 1914 AND TIED IN 1956 AND 1988 JUN 24...103 IN 1914 JUN 25...103 IN 1952 && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
1153 PM CDT MON JUN 22 2015 .UPDATE... ISSUED AT 1152 PM CDT MON JUN 22 2015 KDVN 88D SHOWS THE LAST OF THE SHOWERS AND A FEW THUNDERSTORMS JUST SOUTH OF I-80 IN BUREAU AND PUTNAM COUNTIES DRIFTING SLOWLY E-SE. FURTHER WEST...THE COLD FRONT REACHED FROM NEAR FREEPORT THROUGH THE QUAD CITIES INTO FAR NE MO. BEHIND THE FRONT...NW WINDS WERE SLOWLY ADVECTING IN A LESS HUMID AIRMASS. DEWPOINTS OVER EAST CENTRAL IA WERE STILL IN THE 60S TO AROUND 70...WHILE CENTRAL AND NW IA WERE IN THE 50S. SATELLITE IMAGES SHOWED A LARGE COLD CLOUD TOP ENCOMPASSING THE ENTIRE FORECAST AREA FROM THE MCS COMPLEXES OVER MO...NORTHERN IL INTO LOWER MI. THROUGH THE REST OF TONIGHT...THE FORECAST REMAINS ON TRACK WITH GRADUAL CLEARING AS THE CI CLOUD SHIELD GRADUALLY DRIFTS SOUTHEAST WITH TEMPERATURES COOLING INTO THE LOWER TO MID 60S. THE LAST OF THE SHOWERS SHOULD EXIT BUREAU COUNTY BETWEEN MIDNIGHT AND 1 AM. $$ .SYNOPSIS... ISSUED AT 355 PM CDT MON JUN 22 2015 BOW ECHO THAT PRODUCED 70 TO 90 MPH DESTRUCTIVE WINDS ACROSS OUR FAR NORTHERN COUNTIES THIS MORNING HAS LEFT A RAIN COOLED BOUNDARY NORTH OF I-80. STRONG MOISTURE TRANSPORT AND STRONG SHEAR HAD DEVELOPED AN ISOLATED ELEVATED SEVERE THUNDERSTORM EARLY THIS AFTERNOON IN THE CEDAR RAPIDS AREA...WITH HAIL UP TO BASEBALL SIZE. ISOLATED ELEVATED THUNDERSTORMS WITH MAINLY VERY LARGE HAIL WILL CONTINUE TO FESTER THROUGH THE AFTERNOON. WITH THE CLOUD COVER I HAVE LOWERED TEMPERATURES AND DEWPOINTS SEVERAL DEGREES. LATER THIS AFTERNOON THROUGH THE EVENING...STRONG COLD FRONT IN NW IA WILL BE PUSHING INTO OUR FAR NW CWA BY EVENING. DEWPOINTS WERE IN THE 40S WITH GUSTY NW WINDS BEHIND THE FRONT. CAPES WILL BUILD AS THE AFTERNOON PROGRESSES WITH STORMS BECOMING SURFACE BASED. THE HRRR DEVELOPS DISCRETE SUPERCELLS NEAR HIGHWAY 30 BY MID TO LATE AFTERNOON THEN PROGRESSING SOUTHEAST AND FORMING INTO ANOTHER BOW ECHO. THESE STORMS WILL PRODUCE VERY LARGE HAIL AND A FEW TORNADOES TRANSITIONING TO WIDESPREAD DAMAGING WINDS OF 70+ MPH AS IT PUSHES INTO OUR SOUTHERN AND EASTERN COUNTIES. TO SAY THE LEAST THIS IS ANOTHER DANGEROUS SEVERE WEATHER SITUATION UNFOLDING. THE SEVERE THREAT WILL END WITH THE PASSAGE OF THE FRONT AND SHOULD BE PRETTY MUCH OVER WITH IN THE DVN CWA BY MIDNIGHT. 3 PM TEMPERATURES RANGED FROM THE LOWER 70S IN RAIN AREAS IN OUR NORTH TO THE MID 80S SOUTH. DEWPOINTS WERE IN THE 70S. SPC MESO ANALYSIS INDICATED SBCAPES OF 6000 J/KG IN NW MO WITH A TIGHT GRADIENT OVER EASTERN IA (BEWARE OF THE GRADIENT). EFFECTIVE BULK SHEAR WAS 70 KNOTS...HELICITY 300 M2/S2 WITH 1 KM EHI OF 5. STRONG 850 MB MOISTURE TRANSPORT WAS EVIDENT ALONG WITH PWAT`S OF NEARLY 2 INCHES. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 355 PM CDT MON JUN 22 2015 FORECAST FOCUS ON SEVERE WEATHER THIS EVENING THEN BRIEFLY QUIET ON TUESDAY. TONIGHT...MOST OF THE DETAILS WERE NOTED IN THE SYNOPSIS SECTION ABOVE BUT THE MAIN MESSAGE WILL BE THE SEVERE WEATHER THREAT WILL END BY 10 OR 11 PM. THIS IS DUE TO A COLD FRONT MOVING ACROSS THE CWA AS WINDS TURN NORTHWEST...USHERING COOLER AND LESS HUMID AIR INTO THE AREA. MINIMUM TEMPERATURES WILL RANGE AROUND 60 ALONG HIGHWAY 20 TO THE UPPER 60S FAR SOUTH. TUESDAY...WEAK HIGH PRESSURE WILL PROVIDE A RATHER PLEASANT DAY WITH COMFORTABLE HUMIDITY AND COOLER TEMPERATURES...WITH NORTH WINDS AROUND 10 MPH. DEWPOINTS SHOULD BE IN THE 50S WITH AFTERNOON HIGH TEMPERATURES IN THE UPPER 70S TO LOWER 80S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 355 PM CDT MON JUN 22 2015 FORECAST FOCUS ON THUNDERSTORMS RETURNING TUESDAY NIGHT THROUGH MOST OF THE REMAINDER OF THE WEEK...THEN COOLER BY THE WEEKEND. TUESDAY NIGHT THROUGH FRIDAY...FRONTAL BOUNDARY RETURNS AS A WARM FRONT TUESDAY NIGHT WITH A CHANCE OF STORMS IN OUR FAR SOUTH. ON WEDNESDAY THE FRONT LOOKS TO STALL OVER THE DVN WITH THE POTENTIAL FOR HEAVY RAINFALL AND SEVERE WEATHER AGAIN. SPC HAS THE ENTIRE CWA IN A SLIGHT RISK. DEWPOINTS WILL BE RISING WELL INTO THE 60S TO LOWER 70S WITH AFTERNOON MAXIMUM TEMPERATURES IN THE UPPER 70S NORTH TO UPPER 80S SOUTH. THE ECMWF SUGGESTS THE FRONT TO DROP SOUTHWARD LATE IN THE WEEK WITH ONLY OUR FAR SOUTH STILL HAVING A CHANCE OF STORMS. THE GFS HAS THE FRONT WELL TO OUR SOUTH WITH DRY WEATHER BY FRIDAY. THIS WEEKEND...NORTHWEST TO NORTH FLOW ALOFT WITH COMFORTABLE TEMPERATURES AND HUMIDITY AND MAINLY DRY. HIGHS WILL BE IN THE 70S TO NEAR 80 WITH LOWS AROUND 60. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1152 PM CDT MON JUN 22 2015 VFR CONDITIONS ARE LIKELY THROUGHOUT AS HIGH PRESSURE AND A COOLER...DRIER AIRMASS FOLLOWS A COLD FRONT MOVING THROUGH LATE TONIGHT. LIGHT NW WINDS WILL SHIFT TO THE NORTH FOR TUESDAY WITH ONLY THIN HIGH LEVEL CLOUD COVER EXPECTED. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ UPDATE...SHEETS SYNOPSIS...HAASE SHORT TERM...HAASE LONG TERM...HAASE AVIATION...SHEETS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
236 AM MDT TUE JUN 23 2015 .SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY) ISSUED AT 222 PM MDT MON JUN 22 2015 WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD 597DM RIDGE IN PLACE ACROSS THE SOUTHER PLAINS WITH ZONAL FLOW ACROSS THE NORTHERN US. NORTHERN JET STREAM IS ACROSS THE NORTHERN PLAINS...WITH POSITIVELY TILTED TROUGH OVER NORTHERN MINNESOTA. THERE IS A WEAK SHORTWAVE OVER NORTH CENTRAL COLORADO WITH MINOR HEIGHT FALLS. THIS AFTERNOON-EVENING...VERY HIGH CINH/CAP WILL BE IN PLACE THIS AFTERNOON AND EVENING. FRONT IS NOW ALONG THE SOUTHERN EDGE OF CWA...WITH PRIMARY CONVERGENCE ALONG PRE FRONTAL TROUGH IN SW KANSAS. AT THIS POINT IT SEEMS UNLIKELY THE CAP WILL WEAKEN OR BREAK THIS AFTERNOON OR EARLY THIS EVENING...WITH ANY INITIATION LIMITED TO SW KANSAS OR HIGHER TERRAIN IN COLORADO. TONIGHT-TUESDAY MORNING...SHORTWAVE TROUGH OVERNIGHT COULD COMBINE WITH WEAK H85-H7 WAA ACROSS NE COLORADO TO PRODUCE A FEW ELEVATED THUNDERSTORMS NEAR STALLED FRONTAL ZONE. GUIDANCE IS SHOWING PRECIP SIGNAL IN THIS AREA SPREADING EASTWARD. MOISTURE PROFILES ARE UNIMPRESSIVE WITH LOW MIXING RATIOS/HIGH TD DEPRESSIONS THAT WOULD LIKELY LIMIT CONFIDENCE IN INITIATION OR COVERAGE. IF THUNDERSTORMS WERE TO DEVELOP MODERATE CAPE AND GOOD EFFECTIVE SHEER COULD SUPPORT SEVERE THUNDERSTORM DEVELOPMENT. I AM JUST NOT SURE IF WE ARE GOING TO SEE ANYTHING DEVELOP...SO I KEPT POPS LIMITED TO 20. GUIDANCE SHOWS GOOD BL MOISTURE ADVECTING WIT EASTERLY FLOW NORTH OF FRONT...POSSIBLY POOLING ALONG FRONTAL ZONE IN EASTERN COLORADO LATE TONIGHT/EARLY TUESDAY MORNING. I DECIDED TO KEEP OUT MENTION OF FOG WITH GUIDANCE KEEPING VISIBILITIES HIGH...HOWEVER THIS SHOULD BE MONITORED. TUESDAY...HI RES MODELS GENERALLY SHOW ANY THUNDERSTORM ACTIVITY TRANSITIONING EAST OF THE CWA BY MIDDAY TUESDAY WITH MEAN FLOW...AND I KEPT THIS TIMING IN PLACE. ANOTHER WEAK SHORTWAVE/RIPPLE WITHIN MEAN FLOW BEGINS TO APPROACH THE CWA FROM THE WEST TUESDAY AFTERNOON. FRONT WILL BE IN THE PROCESS OF LIFTING OVER THE CWA...SO WE COULD SEE INCREASING SURFACE CONVERGENCE THROUGH THE LATE AFTERNOON...WHICH COULD BE ENOUGH TO WEAKEN THE DAYTIME CAP. MODELS ARE SHOWING A FAIRLY LARGE SPREAD IN FRONT POSITION/TIMING...SO HIGH TEMPS AND THIS POTENTIAL FOR INITIATION IS UNCERTAIN. BEST MODEL CONSENSUS IS ON DEVELOPMENT BY LATE AFTERNOON IN THE SW...THOUGH THIS COULD STILL BE A LITTLE EARLY BASED ON MODEL TIMING OF BEST UPPER LEVEL FORCING/HEIGHT FALLS. WITH FRONTAL ZONE OVER CWA...THERE COULD BE BETTER SHEER PROFILES WITH VEERING ALONG FRONTAL ZONE AND ESPECIALLY IN THE WEST NEAR SURFACE TROUGH. RESULT COULD BE A BETTER CHANCE FOR SUPERCELL DEVELOPMENT IF THUNDERSTORMS DO DEVELOP. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 233 AM MDT TUE JUN 23 2015 AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE STARTING TO AMPLIFY AN UPPER LEVEL RIDGE OVER THE WESTERN U.S. AND DEEPENING AN UPPER LEVEL TROUGH OVER THE EASTERN U.S. THIS WILL SHIFT THE UPPER LEVEL FLOW TO A MORE NORTHERLY BY THE END OF THE PERIOD. MODELS ARE A LITTLE DIFFERENT IN HOW THEY HANDLE THE POSITION OF THE SURFACE BOUNDARY. SO MADE VERY LITTLE ADJUSTMENTS TO THE CRH_INIT GRIDS. LOOK FOR THE MOST ACTIVE AND WET PART OF THE PERIOD TO BE AT THE BEGINNING OF THE EXTENDED AND LAST INTO SATURDAY NIGHT. AFTER THAT EXPECT DRIER CONDITIONS AS THE RIDGE INFLUENCE THE TRI STATE AREA WITH THE DRY NORTHERLY FLOW. TEMPERATURES WILL NOT WARM UP AS MUCH DUE TO THE NORTHERLY FLOW. IT IS POSSIBLE THAT TEMPERATURES MAY NEED TO BE LOWERED A LITTLE AS WE GET CLOSER TO THIS PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1126 PM MDT MON JUN 22 2015 VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AT KGLD AND KMCK AS HIGH PRESSURE CONTINUES OVER THE REGION. BOUNDARY LAYER RELATIVE HUMIDITY INCREASES OVERNIGHT NEAR THE FRONT WHICH PROVIDES SOME POTENTIAL FOR STRATUS EARLY TUESDAY MORNING AT KGLD. HOWEVER, MODELS INDICATE THAT KGLD SHOULD BE ON THE PERIPHERY OF THE HIGHER RH. LATER TUESDAY EVENING THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AT BOTH SITES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BW AVIATION...FS
AREA FORECAST DISCUSSION
NWS TOPEKA KS
325 AM CDT TUE JUN 23 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 323 AM CDT TUE JUN 23 2015 AN UPPER LEVEL RIDGE CONTINUED TO B CENTERED ACROSS THE SOUTHERN PLAINS AND EXTEND WEST INTO THE SOUTHWEST US. A NEARLY ZONAL MID AND UPPER LEVEL JET EXTENDED ACROSS THE NORTHERN AND CENTRAL PLAINS. A SURFACE COLD FRONT HAS PUSHED SOUTH OF THE CWA AND WAS LOCATED FROM NORTH OF CNU AND EXTENDED WEST-SOUTHWEST TO SOUTH OF P28, THEN WEST TO NORTH OF LBL. THIS FRONT WILL BECOME STATIONARY THROUGH THE MORNING HOURS AND SLOWLY MOVE NORTH THROUGH THE DAY TUESDAYS. ONCE AGAIN THE MODEL SOLUTIONS DIFFER ON QPF ACROSS THE CWA AND MESOSCALE MODELS SUCH AS THE WRF SHOW NO QPF ACROSS THE CWA. EARLY THIS MORNING A FEW SHOWERS WERE BEGINNING TO DEVELOP ACROSS CENTRAL KS IN RESPONSE TO WEAK ISENTROPIC LIFT ALOFT. THE HRRR AND NAM MODELS CONTINUE TO SHOW ELEVATED THUNDERSTORMS DEVELOPING ACROSS CENTRAL KS, THEN MOVING EAST-NORTHEAST ACROSS THE NORTHERN HALF OF THE CWA. THEREFORE, I`LL KEEP A SLIGHT RISK FOR SHOWERS AND THUNDERSTORMS ACROSS THE NORTHERN HALF OF THE CWA THROUGH THE DAY. AT THIS TIME MOST OF THE STORMS LOOK TO BE ELEVATED. IF A SURFACE BASED STORM WERE TO DEVELOP THIS AFTERNOON IT COULD BECOME SEVERE OR STRONG GIVEN MLCAPES OF 2,000 J/KG AND 30 KTS EFFECTIVE SHEAR. HOWEVER, THE WARM TEMPERATURES ALOFT WILL SHOULD LIMIT HAIL SIZE FROM ANY ORGANIZED STORM. HIGHS TODAY WILL BE DEPENDENT ON HOW FAST THE FRONT MOVES NORTH. THE FRONT IS PROGGED TO BE SOUTH OF I-70 BY LATE THIS AFTERNOON. THE SOUTHERN COUNTIES OF THE CWA MAY SEE LOWER TO MID 90S WITH MID TO UPPER 80S ALONG THE I-70 CORRIDOR AND LOWER 80S ALONG THE NE BORDER. TONIGHT, AS THE WARM FRONT MOVES NORTH TO THE NE BORDER. THE BEST ISENTROPIC LIFT WILL OCCUR NORTH OF THE CWA ACROSS NE. I KEPT SLIGHT CHANCE POPS IN THE EXTREME NORTHERN COUNTIES OF THE CWA IN CASE SHOWERS AND STORMS TRY TO BUILD SOUTHWARD TO THE FRONT. ANY COMPLEX OF STORMS THAT DEVELOP ACROSS THE HIGH PLAINS OF NORTHEAST CO AND WESTERN NE SHOULD MOVE EAST ACROSS CENTRAL AND SOUTHERN NE. OVERNIGHT LOWS WILL ONLY DROP BACK TO THE UPPER 60S TO LOWER 70S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 323 AM CDT TUE JUN 23 2015 TOMORROW THE UPPER RIDGE BEGINS TO PROGRESS EASTWARD WHILE THE QUASIZONAL FLOW ACROSS THE NORTHERN US REMAINS ACTIVE WITH SHORTWAVE ACTIVITY. ALTHOUGH THESE SHORTWAVES WILL TRACK NORTH OF THE AREA THEY WILL LIKELY SEND A FRONT SOUTHWARD ACROSS THE REGION DURING THE DAY THURSDAY, WHICH WOULD PLACE THE FORECAST AREA UNDER THE THERMAL RIDGE AXIS TOMORROW. HIGH TEMPERATURES LOOK TO REACH THE MID TO UPPER 90S WITH THE HIGHEST TEMPERATURES LOCATED IN CENTRAL KS CLOSER TO THE THERMAL RIDGE AHEAD OF THE FRONTAL ZONE. DEWPOINT ARE FORECAST TO BE IN THE UPPER 60S TO LOW 70S CAUSING HEAT INDICES TO REACH THE LOW 100S. ON THURSDAY THE FRONT SLIDES THROUGH NORTHEAST KS BRINGING THE CHANCE FOR SCATTERED THUNDERSTORMS MOST LIKELY DURING PEAK HEATING. DEPENDING ON THE FRONTAL PLACEMENT THERE COULD BE A DECENT TEMPERATURE GRADIENT ACROSS THE AREA WITH THE NORTHERN COUNTIES IN THE 80S AND SOUTHERN COUNTIES IN THE 90S. STORM COVERAGE SHOULD BE DETERMINED BY WHERE THE CAP BREAKS AND IF CONVERGENCE ALONG THE FRONT CAN SUPPLY ENOUGH LIFT. BEHIND THE FRONT THE MID/UPPER LEVEL TROUGH BEGINS TO DIG INTO THE CENTER OF THE COUNTRY. THIS WILL ENHANCE THE LIFT OVER THE FRONTAL ZONE, AND SUPPORT A BETTER CHANCE OF PRECPITITATION THURSDAY NIGHT INTO FRIDAY. NORTHWEST FLOW ALOFT THEN BECOMES MORE ESTABLISHED THROUGH THE REST OF THE WEEK BRINGING COOLER TEMPERATURES INTO THE REGION. ALSO, THE MODELS ARE HINTING AT SHORTWAVES TRACKING OUT OF CANADA AND OVER THE UPPER MIDWEST AND GREAT LAKES REGION BRINGING MORE CHANCE FOR SHOWERS AND STORMS. THIS ACTIVITY APPEARS TO OCCUR LATE WEEKEND INTO EARLY NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1125 PM CDT MON JUN 22 2015 FOR THE 06Z TAFS, THE COLD FRONT WAS SHIFTING SOUTH OF THE TAF SITES WITH WINDS VEERING TOWARD THE NORTH. WINDS SHOULD CONTINUE TO SHIFT TO THE EAST AND SOUTHEAST THROUGH THE DAY AS THE FRONT REMAINS SOUTH OF THE AREA. HOWEVER, IT IS EXPECTED TO LIFT NORTHWARD AS A WARM FRONT TUESDAY NIGHT. THERE IS A SLIGHT CHANCE FOR A FEW VERY ISOLATED SHOWERS AND STORMS TO DEVELOP ALONG THIS LINGERING BOUNDARY LATE THIS AFTERNOON, HOWEVER CONFIDENCE IS TOO LOW TO WARRANT A MENTION IN THE TAFS. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GARGAN LONG TERM...SANDERS AVIATION...HENNECKE
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1130 PM MDT MON JUN 22 2015 .SHORT TERM...(THIS AFTERNOON THROUGH TUESDAY) ISSUED AT 222 PM MDT MON JUN 22 2015 WV IMAGERY AND RAP H5 ANALYSIS SHOWS BROAD 597DM RIDGE IN PLACE ACROSS THE SOUTHER PLAINS WITH ZONAL FLOW ACROSS THE NORTHERN US. NORTHERN JET STREAM IS ACROSS THE NORTHERN PLAINS...WITH POSITIVELY TILTED TROUGH OVER NORTHERN MINNESOTA. THERE IS A WEAK SHORTWAVE OVER NORTH CENTRAL COLORADO WITH MINOR HEIGHT FALLS. THIS AFTERNOON-EVENING...VERY HIGH CINH/CAP WILL BE IN PLACE THIS AFTERNOON AND EVENING. FRONT IS NOW ALONG THE SOUTHERN EDGE OF CWA...WITH PRIMARY CONVERGENCE ALONG PRE FRONTAL TROUGH IN SW KANSAS. AT THIS POINT IT SEEMS UNLIKELY THE CAP WILL WEAKEN OR BREAK THIS AFTERNOON OR EARLY THIS EVENING...WITH ANY INITIATION LIMITED TO SW KANSAS OR HIGHER TERRAIN IN COLORADO. TONIGHT-TUESDAY MORNING...SHORTWAVE TROUGH OVERNIGHT COULD COMBINE WITH WEAK H85-H7 WAA ACROSS NE COLORADO TO PRODUCE A FEW ELEVATED THUNDERSTORMS NEAR STALLED FRONTAL ZONE. GUIDANCE IS SHOWING PRECIP SIGNAL IN THIS AREA SPREADING EASTWARD. MOISTURE PROFILES ARE UNIMPRESSIVE WITH LOW MIXING RATIOS/HIGH TD DEPRESSIONS THAT WOULD LIKELY LIMIT CONFIDENCE IN INITIATION OR COVERAGE. IF THUNDERSTORMS WERE TO DEVELOP MODERATE CAPE AND GOOD EFFECTIVE SHEER COULD SUPPORT SEVERE THUNDERSTORM DEVELOPMENT. I AM JUST NOT SURE IF WE ARE GOING TO SEE ANYTHING DEVELOP...SO I KEPT POPS LIMITED TO 20. GUIDANCE SHOWS GOOD BL MOISTURE ADVECTING WIT EASTERLY FLOW NORTH OF FRONT...POSSIBLY POOLING ALONG FRONTAL ZONE IN EASTERN COLORADO LATE TONIGHT/EARLY TUESDAY MORNING. I DECIDED TO KEEP OUT MENTION OF FOG WITH GUIDANCE KEEPING VISIBILITIES HIGH...HOWEVER THIS SHOULD BE MONITORED. TUESDAY...HI RES MODELS GENERALLY SHOW ANY THUNDERSTORM ACTIVITY TRANSITIONING EAST OF THE CWA BY MIDDAY TUESDAY WITH MEAN FLOW...AND I KEPT THIS TIMING IN PLACE. ANOTHER WEAK SHORTWAVE/RIPPLE WITHIN MEAN FLOW BEGINS TO APPROACH THE CWA FROM THE WEST TUESDAY AFTERNOON. FRONT WILL BE IN THE PROCESS OF LIFTING OVER THE CWA...SO WE COULD SEE INCREASING SURFACE CONVERGENCE THROUGH THE LATE AFTERNOON...WHICH COULD BE ENOUGH TO WEAKEN THE DAYTIME CAP. MODELS ARE SHOWING A FAIRLY LARGE SPREAD IN FRONT POSITION/TIMING...SO HIGH TEMPS AND THIS POTENTIAL FOR INITIATION IS UNCERTAIN. BEST MODEL CONSENSUS IS ON DEVELOPMENT BY LATE AFTERNOON IN THE SW...THOUGH THIS COULD STILL BE A LITTLE EARLY BASED ON MODEL TIMING OF BEST UPPER LEVEL FORCING/HEIGHT FALLS. WITH FRONTAL ZONE OVER CWA...THERE COULD BE BETTER SHEER PROFILES WITH VEERING ALONG FRONTAL ZONE AND ESPECIALLY IN THE WEST NEAR SURFACE TROUGH. RESULT COULD BE A BETTER CHANCE FOR SUPERCELL DEVELOPMENT IF THUNDERSTORMS DO DEVELOP. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 324 PM MDT MON JUN 22 2015 FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH THURSDAY AND HOW HOT DOES IT GET. SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST OF THE SOUTHERN HALF OF THE COUNTRY. AT JET LEVEL...MODELS STARTED OUT FINE. AT MID LEVELS...THE GFS AND CANADIAN WERE DOING A LITTLE BETTER THAN THE REMAINING OUTPUT. THE ECMWF WAS DOING A LITTLE BETTER THAN THE NAM. THE GFS...CANADIAN... AND THE ECMWF WERE DOING THE BEST ON THE LOW LEVEL THERMAL FIELD. TUESDAY NIGHT...MAIN JET WELL NORTH. POSSIBLY A WEAK REAR QUADRANT THAT MOVES ACROSS NEAR OR JUST NORTH OF OUR AREA. SURFACE TROUGH RESIDES OVER THE FAR WESTERN PORTION OF THE AREA LATE IN THE AFTERNOON/EARLY EVENING. AT THE SAME TIME A SHORTWAVE TROUGH WILL BEGIN AFFECTING THE FAR WEST LATE IN THE DAY AND THEN MOVE ACROSS THE AREA THROUGH THE REMAINDER OF THE NIGHT. PROBLEM IN THE BEGINNING COULD BE IF THE CAP IS TOO STRONG PLUS THE MODELS DIFFER ON HOW STRONG THE MID LIFT WILL BE. MODEL QPF IS NOT OVERLY IMPRESSIVE BUT IT DOES LOOK LIKE WE SHOULD BE GETTING MORE THAN WHAT IS CURRENTLY SHOWN. CHOSE TO PLAY IT CONSERVATIVELY AND ONLY GO SLIGHT CHANCE AT THIS TIME. WEDNESDAY/WEDNESDAY NIGHT...A LOT OF MODEL DIFFERENCES START SHOWING UP. A WEAKER RIGHT REAR QUADRANT STARTS AFFECTING THE NORTHERN THIRD TO HALF OF THE AREA DURING THE AFTERNOON INTO AT LEAST THE EVENING AND POSSIBLY INTO THE OVERNIGHT HOURS DEPENDING ON WHICH MODEL YOU CHOOSE. A SHORTWAVE TROUGH AND ITS SURFACE REFLECTION MOVE INTO THE NORTHWEST OF THE AREA BY 18Z AND THEN PROGRESS IT SOUTH AND EAST THROUGH THE AREA. PROBLEM IS IN HOW AGGRESSIVE THEY ARE IN MOVING THE FRONT THROUGH. THE NAM IS THE FASTEST WITH THE GFS MUCH SLOWER AND ONLY ABOUT HALF WAY THROUGH THE AREA BY LATE IN THE DAY. THE ECMWF IS SLIGHTLY SLOWER THAN THE NAM. AT THE SAME TIME THE MID LEVEL TEMPERATURES ARE NEAR PLUS 15. SO WHERE WILL THE SURFACE FOCUS BE AND IF THE CAP WILL BREAK. ALSO THE STRENGTH OF THE MID LIFT IS IN QUESTION. AGAIN DUE TO A LOT OF MODEL DIFFERENCE ON TIMING AND STRENGTH OF FEATURES...NOT A LOT OF CONFIDENCE IN WHAT WILL HAPPEN. SO ONCE AGAIN CHOSE ONLY TO GO SLIGHT CHANCE BUT IF BETTER MODEL AGREEMENT WOULD HAPPEN WOULD FEEL A HIGHER CHANCE IS DESERVED. DUE TO THE BIG MODEL DIFFERENCES IN WHERE THE BOUNDARY...THERE IS A HUGE DIFFERENCE IN HOW WARM THEY MAKE IT. CHOSE TO GO IN THE MIDDLE AND CLOSER TO THE OUTPUT THAT HAS BEEN DOING BETTER RECENTLY. THURSDAY...DIFFERENCE IN FRONTAL POSITION CONTINUE. MAJORITY OF THE OUTPUT WOULD SUPPORT THE FRONT BEING A LITTLE FURTHER SOUTH OF THE FORECAST AREA. SO FELT BETTER ABOUT GOING COOLER. PROXIMITY OF THE BOUNDARY AND MID LEVEL LIFT ROUGHLY ALONG THE SOUTHERN AND WESTERN HOURS SUPPORT HAVING THE AFTERNOON POPS IN THE SOUTH AND WEST BUT NOT VERY CONFIDENT. THURSDAY NIGHT THROUGH MONDAY...MODELS START THE AMPLIFICATION PROCESS TO A STRONG WESTERN RIDGE AND EASTERN CONUS TROUGH. FLOW BECOMES SHIFTS MORE TOWARD THE NORTH BY THE END OF THE PERIOD. MODELS HAVING A LOT OF DIFFERENCE IN HOW THEY HANDLE THE POSITION OF WHERE THE SURFACE BOUNDARY ENDS UP. MORE THAN LIKELY WILL INITIALLY HAVE THE FRONT STAY OR START JUST TO THE SOUTH OF THE FORECAST AREA AND THEN WILL HAVE ADDITIONAL COLD INTRUSIONS. DID NOT MAKE ANY CHANGES TO WHAT THE CRH_INIT GRIDS GAVE ME DUE TO THE INITIAL UNCERTAIN ABOUT THE SURFACE FEATURES. THE MOST ACTIVE AND WET PART OF THE PERIOD WILL BE THURSDAY NIGHT INTO SATURDAY NIGHT. AFTER THAT IT BECOMES DRIER AS THE RIDGE EXERTS ITS INFLUENCE ALONG WITH THE DRIER NORTHERLY FLOW. ONLY ISOLATED PRECIPITATION IS EXPECTED FROM SUNDAY INTO MONDAY. TEMPERATURES WILL NOT WARM UP TOO MUCH DUE TO THE NORTHERLY FLOW. MAY BE POSSIBLE THAT TEMPERATURES MAY NEED TO BE LOWERED A LITTLE AS WE GET CLOSER TO THIS PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1126 PM MDT MON JUN 22 2015 VFR CONDITIONS WILL CONTINUE FOR THE NEXT 24 HOURS AT KGLD AND KMCK AS HIGH PRESSURE CONTINUES OVER THE REGION. BOUNDARY LAYER RELATIVE HUMIDITY INCREASES OVERNIGHT NEAR THE FRONT WHICH PROVIDES SOME POTENTIAL FOR STRATUS EARLY TUESDAY MORNING AT KGLD. HOWEVER, MODELS INDICATE THAT KGLD SHOULD BE ON THE PERIPHERY OF THE HIGHER RH. LATER TUESDAY EVENING THERE IS A SLIGHT CHANCE OF THUNDERSTORMS AT BOTH SITES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BULLER AVIATION...FS
AREA FORECAST DISCUSSION
NWS JACKSON KY
340 AM EDT TUE JUN 23 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 A COUPLE OF BOUNDARIES TO KEEP AN EYE ON TODAY. THE FIRST ONE IS CROSSING INTO CENTRAL KENTUCKY PRESENTLY AND HAS BEEN VISIBLE ON AREA RADARS. THE SECOND BOUNDARY WILL BE A COLD FRONT ACROSS THE LOWER GREAT LAKES THAT WILL SWEEP SOUTH ACROSS THE AREA LATER TODAY. IN THE IMMEDIATE SHORT TERM...FOCUS IS ON THE FIRST BOUNDARY. HRRR CONTINUES TO SHOW SOME DEVELOPMENT ALONG THE BOUNDARY POSSIBLE AS IT SHIFTS EAST ACROSS THE AREA THROUGH DAYBREAK. NOT MUCH NOTED SO FAR...AND THE RAP HAS BACKED OFF ON THE POSSIBLE CONVECTION. WILL MAINTAIN SOME SLIGHT CHANCE POPS AS THIS BOUNDARY PROGRESSES ACROSS THE AREA THIS MORNING. IT LOOKS LIKE A LULL IS EXPECTED THROUGH MUCH OF THE COMING DAY AS WE WAIT FOR THE COLD FRONT TO THE NORTH TO DROP SOUTH. THIS SHOULD HAPPEN BY 2 PM WITH CHANCES OF SHOWERS AND STORMS MOVING INTO THE I-64 CORRIDOR. THE CHANCES WILL SPREAD SOUTH THROUGH THE REMAINDER OF THE AFTERNOON/EVENING. STILL HESITANT TO GO UP TO LIKELY POPS GIVEN THE MAIN FORCING IS EXPECTED TO STAY TO OUR NORTHEAST...BUT GIVEN THE BOUNDARY...WE SHOULD AT LEAST SEE SOME SCATTERED COVERAGE OF SHOWERS/STORMS...ESPECIALLY GIVEN THE INSTABILITY DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON. BETTER SHEAR IS OFF TO OUR NORTHEAST WHERE THERE IS AN ENHANCED AREA FOR SEVERE THUNDERSTORMS. HOWEVER...WITH MARGINAL SHEAR OVER THE AREA...A FEW STORMS COULD PRODUCE A SEVERE WIND GUST. HAIL THREAT IS PRETTY LOW WITH FREEZING LEVELS AT OR ABOVE 15KFT. OVERALL...SEVERE THREAT IS NOT LOOKING ALL THAT GREAT...BUT JUST GOOD ENOUGH FOR THE SEVERE STORM PREDICTION CENTER TO MAINTAIN THE SLIGHT CHANCE OF SEVERE STORMS OVER EASTERN KENTUCKY. WILL CONTINUE TO HIGHLIGHT DAMAGING WINDS AS THE MAIN THREAT. FRONTAL BOUNDARY LOOKS TO DIVE A BIT FARTHER SOUTH TONIGHT...WHICH WILL TAKE THE CONVECTION TO THE SOUTH. ANY POSSIBLE MCS DEVELOPING UPSTREAM WILL ALSO STAY SOUTH GIVEN THE FRONTAL PLACEMENT. THIS SHOULD SPELL A DRY NIGHT. HOWEVER...WITH COOLER AIR FILTERING IN FROM THE NORTH AND SURFACE MOISTURE LIKELY LAGGING BEHIND THE FRONT...WE MAY SEE SOME DENSE FOG DEVELOP TONIGHT. GUIDANCE IS HITTING THE FOG FAIRLY HARD...AND SEE NO REASON TO NOT DO THE SAME. THUS...WILL MENTION WIDESPREAD DENSE FOG IN THE VALLEYS WITH MORE PATCHY ON THE RIDGES. THE BLUEGRASS REGION MAY MAINTAIN ENOUGH WIND TO LIMIT THE FOG POTENTIAL OUT THAT WAY. WEDNESDAY IS LOOKING MORE LIKE A DRY DAY AS THE FRONT SETTLES WELL TO OUR SOUTH. WE COULD POP OFF A SHOWER OR STORM IN SOUTHEAST KENTUCKY...BUT GUIDANCE HAS REALLY CUT BACK ON POPS FOR MOST OF THE AREA. THUS...WILL GO TOWARDS A DRIER SOLUTION FOR THE DAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 340 AM EDT TUE JUN 23 2015 A CHANGE TO THE OVERALL PATTERN IS ON THE HORIZON IN THE LONG TERM PERIOD. THE PERIOD WILL BEGIN WITH UPPER LEVEL HIGH STILL GENERALLY CENTERED ACROSS THE SE US WITH BEST JET ENERGY ACROSS THE GREAT LAKES AND SOUTHERN NEW ENGLAND. MODELS ARE IN GOOD AGREEMENT WITH THE RIDGE BREAKING DOWN AS WE MOVE TOWARD FRIDAY TIME FRAME WITH UPPER LEVEL HIGH SHIFTING ACROSS THE WESTERN US. THIS WILL INTRODUCE HEIGHT FALLS ACROSS THE EASTERN US AS TROUGH IS EXPECTED TO CONTINUE TO AMPLIFY/CUTOFF ACROSS THE EASTERN GREAT LAKES. HOWEVER RIGHT NOW THE GFS/CANADIAN/GFS ENSEMBLE ARE MOST AMPLIFIED COMPARED TO THE ECMWF WITH SUB 576 HEIGHTS MAKING IT INTO THE OHIO VALLEY. WEAK SURFACE HIGH WILL BE OFF TO THE NORTH AND WARM FRONT SOUTH OF THE REGION ON WEDNESDAY NIGHT TO BEGIN THE LONG TERM PERIOD. THIS WILL BE SHORT LIVED WITH ACTIVE PATTERN AND TROUGHING SETTING UP ACROSS THE EASTERN US. THE FRONT WILL MEANDER AROUND THE REGION THROUGH THE PERIOD WITH SEVERAL AREAS OF LOW PRESSURE DEVELOPING. THIS BOUNDARY WILL BE THE FOCUS OF CONVECTION THROUGH THE PERIOD AND WILL GIVE WAY TO MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS THURSDAY INTO SATURDAY. A FRONTAL BOUNDARY NEAR THE REGION...UPPER 60S TO LOW 70 DEWPOINTS...CAPES AOA 2000 J/KG...DCAPES NEARING 1000 J/KG...AND BULK SHEAR NEARING 30 KNOTS WITH LOWERING HEIGHTS WILL LEAD TO STRONG TO EVEN POTENTIAL FOR SEVERE STORMS THURSDAY INTO FRIDAY. THE MAIN THREAT LOOKS TO BE STRONG WINDS AND HEAVY RAIN WITH ONLY MARGINAL HAIL POTENTIAL GIVEN HIGHER FREEZING LEVELS AROUND 13 TO 14 KFT. RAIN THREAT WILL SUBSIDE AS WE MOVE LATE INTO THE WEEKEND...AS LOW PRESSURE SYSTEM AND BOUNDARY MOVE SOUTH AND EAST OF THE REGION WITH HIGH PRESSURE MOVING EAST. THIS WILL USHER IN COOLER AND DRYER CONDITIONS AS WE MOVE INTO THE SUNDAY TIME FRAME. HOWEVER UNDER NW FLOW ALOFT AND UPPER LEVEL TROUGH PASSING OVER COULD LEAD TO STRATUS DECK HANGING ON. THIS STRATUS IS SUGGESTED BY THE GFS FORECAST SOUNDINGS AND ECMWF TIME HEIGHTS. RIGHT NOW CONFIDENCE FOR MONDAY IS LOWER BUT DID OPT TO KEEP SOME SLIGHT POPS AT THIS POINT. TEMPERATURES WILL BEGIN ABOVE NORMAL FOR THIS TIME OF YEAR ON THURSDAY. TEMPERATURE FRIDAY BEGIN TO SHIFT TO AT OR NEAR NORMAL BEFORE A BELOW NORMAL SHIFT WITH HIGHS ON POTENTIALLY STAYING IN THE LOW TO MID 70S SUNDAY. THIS WOULD BE 10 OR MORE DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 222 AM EDT TUE JUN 23 2015 OUTSIDE OF SOME PATCHY VALLEY FOG IN THE EASTERN VALLEYS TONIGHT...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD. SOME THUNDERSTORMS MAY DEVELOP ALONG AN APPROACHING COLD FRONT LATER THIS AFTERNOON AND EVENING. COVERAGE IS STILL UNCERTAIN AT THIS TIME...BUT WILL INTRODUCE SOME VCTS TO PROVIDE A WINDOW OF OPPORTUNITY FOR CONVECTION LATER TODAY. AS THE FRONT PASSES TONIGHT...COOLER AIR WILL FILTER INTO THE REGION...BUT MOISTURE MAY LINGER A BIT LONGER WHICH COULD SET THE STAGE FOR SOME DENSE FOG TONIGHT. THIS WILL HAVE THE POTENTIAL TO DROP CIGS OR VISIBILITIES BELOW AIRPORT MINIMUMS LATE TUESDAY NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...DJ AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
310 AM EDT TUE JUN 23 2015 .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 A COUPLE OF BOUNDARIES TO KEEP AN EYE ON TODAY. THE FIRST ONE IS CROSSING INTO CENTRAL KENTUCKY PRESENTLY AND HAS BEEN VISIBLE ON AREA RADARS. THE SECOND BOUNDARY WILL BE A COLD FRONT ACROSS THE LOWER GREAT LAKES THAT WILL SWEEP SOUTH ACROSS THE AREA LATER TODAY. IN THE IMMEDIATE SHORT TERM...FOCUS IS ON THE FIRST BOUNDARY. HRRR CONTINUES TO SHOW SOME DEVELOPMENT ALONG THE BOUNDARY POSSIBLE AS IT SHIFTS EAST ACROSS THE AREA THROUGH DAYBREAK. NOT MUCH NOTED SO FAR...AND THE RAP HAS BACKED OFF ON THE POSSIBLE CONVECTION. WILL MAINTAIN SOME SLIGHT CHANCE POPS AS THIS BOUNDARY PROGRESSES ACROSS THE AREA THIS MORNING. IT LOOKS LIKE A LULL IS EXPECTED THROUGH MUCH OF THE COMING DAY AS WE WAIT FOR THE COLD FRONT TO THE NORTH TO DROP SOUTH. THIS SHOULD HAPPEN BY 2 PM WITH CHANCES OF SHOWERS AND STORMS MOVING INTO THE I-64 CORRIDOR. THE CHANCES WILL SPREAD SOUTH THROUGH THE REMAINDER OF THE AFTERNOON/EVENING. STILL HESITANT TO GO UP TO LIKELY POPS GIVEN THE MAIN FORCING IS EXPECTED TO STAY TO OUR NORTHEAST...BUT GIVEN THE BOUNDARY...WE SHOULD AT LEAST SEE SOME SCATTERED COVERAGE OF SHOWERS/STORMS...ESPECIALLY GIVEN THE INSTABILITY DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON. BETTER SHEAR IS OFF TO OUR NORTHEAST WHERE THERE IS AN ENHANCED AREA FOR SEVERE THUNDERSTORMS. HOWEVER...WITH MARGINAL SHEAR OVER THE AREA...A FEW STORMS COULD PRODUCE A SEVERE WIND GUST. HAIL THREAT IS PRETTY LOW WITH FREEZING LEVELS AT OR ABOVE 15KFT. OVERALL...SEVERE THREAT IS NOT LOOKING ALL THAT GREAT...BUT JUST GOOD ENOUGH FOR THE SEVERE STORM PREDICTION CENTER TO MAINTAIN THE SLIGHT CHANCE OF SEVERE STORMS OVER EASTERN KENTUCKY. WILL CONTINUE TO HIGHLIGHT DAMAGING WINDS AS THE MAIN THREAT. FRONTAL BOUNDARY LOOKS TO DIVE A BIT FARTHER SOUTH TONIGHT...WHICH WILL TAKE THE CONVECTION TO THE SOUTH. ANY POSSIBLE MCS DEVELOPING UPSTREAM WILL ALSO STAY SOUTH GIVEN THE FRONTAL PLACEMENT. THIS SHOULD SPELL A DRY NIGHT. HOWEVER...WITH COOLER AIR FILTERING IN FROM THE NORTH AND SURFACE MOISTURE LIKELY LAGGING BEHIND THE FRONT...WE MAY SEE SOME DENSE FOG DEVELOP TONIGHT. GUIDANCE IS HITTING THE FOG FAIRLY HARD...AND SEE NO REASON TO NOT DO THE SAME. THUS...WILL MENTION WIDESPREAD DENSE FOG IN THE VALLEYS WITH MORE PATCHY ON THE RIDGES. THE BLUEGRASS REGION MAY MAINTAIN ENOUGH WIND TO LIMIT THE FOG POTENTIAL OUT THAT WAY. WEDNESDAY IS LOOKING MORE LIKE A DRY DAY AS THE FRONT SETTLES WELL TO OUR SOUTH. WE COULD POP OFF A SHOWER OR STORM IN SOUTHEAST KENTUCKY...BUT GUIDANCE HAS REALLY CUT BACK ON POPS FOR MOST OF THE AREA. THUS...WILL GO TOWARDS A DRIER SOLUTION FOR THE DAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 LONG TERM DISCUSSION WILL FOLLOW SHORTLY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 222 AM EDT TUE JUN 23 2015 OUTSIDE OF SOME PATCHY VALLEY FOG IN THE EASTERN VALLEYS TONIGHT...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD. SOME THUNDERSTORMS MAY DEVELOP ALONG AN APPROACHING COLD FRONT LATER THIS AFTERNOON AND EVENING. COVERAGE IS STILL UNCERTAIN AT THIS TIME...BUT WILL INTRODUCE SOME VCTS TO PROVIDE A WINDOW OF OPPORTUNITY FOR CONVECTION LATER TODAY. AS THE FRONT PASSES TONIGHT...COOLER AIR WILL FILTER INTO THE REGION...BUT MOISTURE MAY LINGER A BIT LONGER WHICH COULD SET THE STAGE FOR SOME DENSE FOG TONIGHT. THIS WILL HAVE THE POTENTIAL TO DROP CIGS OR VISIBILITIES BELOW AIRPORT MINIMUMS LATE TUESDAY NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...KAS LONG TERM...DJ AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
222 AM EDT TUE JUN 23 2015 .UPDATE... ISSUED AT 222 AM EDT TUE JUN 23 2015 05Z RAP HAS BACKED OFF ON PRECIPITATION THIS MORNING...BUT HRRR CONTINUES TO REMAIN PERSISTENT WITH DEVELOPING SOME ISOLATED ACTIVITY. WILL HOLD THE LINE WITH SOME LOW POPS TO BE SAFE AS THERE IS STILL AN APPARENT BOUNDARY SHIFTING EAST INTO THE AREA. THIS BOUNDARY IS PRESENTLY BETWEEN FRANKFORT AND LOUISVILLE. UPDATE ISSUED AT 1248 AM EDT TUE JUN 23 2015 LAST FEW RUNS OF THE HRRR/RAP SHOW SOME CONVECTION DEVELOPING ALONG AN OUTFLOW BOUNDARY SAGGING SOUTHWARD ACROSS SOUTHERN INDIANA/OHIO. GIVEN THE AIRMASS AND POTENTIAL FOR LIFT WITH A DEVELOPING LOW LEVEL JET OVERNIGHT...IT APPEARS THE HI-RES MODELS MAY BE ONTO SOMETHING WITH THIS DEVELOPMENT. THUS...WILL TOSS IN SOME SLIGHT CHANCE POPS FOR THE LATE OVERNIGHT/EARLY MORNING PERIOD AS THIS BOUNDARY SAGS SOUTHEASTWARD. LOOKS LIKE THE BOUNDARY SHOULD REACH OUR NORTHWEST COUNTIES AROUND 06Z AND REACH THE FAR SOUTHEAST TOWARDS DAYBREAK. IF WE DO GET CONVECTION...OUTFLOWS FROM CONVECTION COULD KEEP STUFF GOING PAST SUNRISE...BUT IT DOES LOOK LIKE WE SHOULD DRY OUT BY MID MORNING BEFORE CONVECTION WITH THE FRONT SPREADS IN FROM THE NORTH LATER IN THE DAY. UPDATE ISSUED AT 745 PM EDT MON JUN 22 2015 A WARM AND HUMID AIRMASS REMAINS ACROSS EASTERN KY AS UPPER LEVEL RIDGING HAS BUILT A BIT FURTHER EAST INTO THE SOUTHEASTERN U.S. AT THE SFC...THE REGION REMAINS IN THE WARM SECTOR AS AN AREA OF SFC LOW PRESSURE TRACKS ACROSS THE NORTHERN GREAT LAKES AND INTO ONTARIO AND QUEBEC. THE TRAILING COLD FRONT WILL APPROACH THE OH VALLEY BY LATE TONIGHT. HOWEVER...MOST...IF NOT ALL THE CONVECTION ACROSS EASTERN KY SHOULD HOLD OFF UNTIL THE FRONT NEARS AND IS COUPLED WITH DAYTIME HEATING ON TUESDAY. AN AREA OF MID AND HIGH CLOUDS CONTINUES TO DROP SOUTHEAST INTO EASTERN KY. THESE HAVE TO SOME EXTENT DIMINISHED OVER THE PAST COUPLE OF HOURS. OTHER THAN TO FRESHEN UP HOURLY TEMPERATURE AND DEWPOINT GRIDS...SKY COVER HAS ALSO BEEN ADJUSTED UP TO ACCOUNT FOR THE CLOUD DROPPING SOUTH. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 300 PM EDT MON JUN 22 2015 FAST MOVING SHORT WAVE ENERGY EMBEDDED WITHIN A ZONAL FLOW PATTERN ACROSS THE NORTHERN TIER AND GREAT LAKES WILL BATTLE AGAINST AN ELONGATED AND FLAT RIDGE THAT WILL ATTEMPT TO NOSE ITS WAY INTO THE TN VALLEY REGION DURING THE SHORT TERM. SENSIBLE WEATHER WILL DEPEND ON WHICH FEATURE EXERTS THE GREATER INFLUENCE OVER OUR AREA. CURRENT RUNS...AND PAST TRENDS FAVOR THE NORTHERN STREAM SYSTEMS. MODEL SOLUTIONS ARE IN VERY GOOD AGREEMENT WITH DETAILS THROUGH THE SHORT TERM. A SFC COLD FRONTAL BOUNDARY WILL MANAGE TO DIG ITS WAY SOUTHWARD INTO THE COMMONWEALTH BEFORE STALLING OUT JUST TO OUR SOUTH BY LATE TUESDAY NIGHT...EARLY WEDNESDAY MORNING. SPC HAS PLACED OUR AREA WITHIN A SLIGHT RISK FOR SEVERE THUNDERSTORMS TOMORROW AS THIS COLD FRONTAL BOUNDARY SLIDES INTO A DESTABILIZED AIR MASS. DAMAGING WINDS AND LARGE HAIL WILL BE THE PRIMARY THREATS DURING THE AFTERNOON AND EARLY EVENING TIME FRAME. TEMPERATURES WILL CONTINUE TO RUN WELL ABOVE NORMAL. AMPLE MOISTURE AT THE SFC WILL ALLOW HEAT INDICES TO CLIMB WELL INTO THE 90S...TO NEAR 100 AT PEAK HEATING DURING THE AFTERNOON. OVERNIGHT LOWS WILL PROVIDE ONLY MINOR RELIEF...DROPPING INTO THE MID TO LOWER 70S FOR MOST LOCATIONS...THOUGH OUR TYPICALLY COOLER VALLEY LOCATIONS WILL LIKELY DROP INTO THE UPPER 60S TUESDAY MORNING. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 342 PM EDT MON JUN 22 2015 BROAD RIDGING ACROSS MUCH OF THE SOUTHERN CONUS WILL STILL BE IN PLACE BY MID WEEK...WITH STRONG WNW UPPER LEVEL FLOW ACROSS EASTERN KY. THE RIDGE WILL THEN SHIFT BACK TO THE WEST TOWARDS THE FOUR CORNER STATES AS MORE AMPLIFIED PATTERN SETS UP ACROSS THE EASTERN CONUS BY THE END OF THE WEEK...WITH DEEPENING SHORTWAVES AND FALLING HEIGHTS. BY SATURDAY...THE EASTERN CONUS WILL FIND ITSELF IN IN A STRONG UPPER LEVEL TROUGHING PATTERN IN WHICH MODELS ARE IN VERY GOOD AGREEMENT. THIS PATTERN WILL LIKELY REMAIN IN PLACE THROUGH THE REMAINDER OF THE EXTENDED AS THE UPPER LEVEL RIDGE BECOMES TRAPPED ACROSS THE WESTERN CONUS. AT THE SURFACE...A FRONTAL BOUNDARY WILL HAVE SET UP ALONG THE WNW FLOW...AND WILL REMAIN IN PLACE THROUGH THE WORK WEEK. EACH SHORTWAVE THAT MOVES THROUGH ALOFT WILL LIKELY INTERACT WITH THIS BOUNDARY AND BRING CONTINUED CHANCES OF SHOWERS/THUNDERSTORMS...AND EVEN SOME MCS ACTIVITY AS THE NW FLOW DEEPENS. WITH HEAT AND HUMIDITY HELPING TO PLAY A ROLL...EXPECT BEST CHANCES FOR CONVECTION TO OCCUR DURING THE AFTERNOON AND EVENING HOURS. AT 12Z WEDNESDAY...THE FRONTAL BOUNDARY WILL BE LOCATED JUST TO OUR SOUTH...WITH GENERALLY LIGHT WINDS AND DECENT HEATING CONTINUING. BEST CHANCES FOR AFTERNOON CONVECTION WILL THEREFORE MAINLY AFFECT THE SOUTHERN 1/2 TO 2/3 OF THE CWA UNLESS THE BOUNDARY SHIFTS FARTHER NORTH OR SOUTH. A SURFACE LOW WILL EJECT OUT OF THE CENTRAL PLAINS EASTWARD TOWARD THE OHIO RIVER VALLEY DURING THE DAY THURSDAY...PLACING ANOTHER WEAK SURFACE BOUNDARY JUST TO OUR NORTH. THIS FRONT IS EXPECTED TO SHIFT SOUTH THURSDAY EVENING...THEN GET HUNG UP ACROSS KY THROUGH THE WEEKEND. THIS WILL BRING OUR BEST SLAM DUNK RAIN AND THUNDERSTORM CHANCES FOR THE FORECAST PERIOD...WITH RAIN EXPECTED TO MOVE IN THURSDAY EVENING/OVERNIGHT JUST AHEAD OF THE SURFACE FRONT...AND CONTINUE THROUGH THE WEEKEND. AS NOTED ABOVE...EXPECT HEAVIEST CONVECTION DURING THE AFTERNOON AND EVENING HOURS WITH PEAK HEATING. THURSDAY EVENING INTO FRIDAY WILL ALSO EXHIBIT THE BEST INSTABILITY UNDER SW FLOW...WITH CAPE VALUES TOPPING OUT ABOVE 3 AND 4000 J/KG...AND DECENT CONVERGENCE IN PLACE. INTERESTINGLY ENOUGH...THE LAPSE RATES WILL BE QUITE WEAK...BUT STILL EXPECT THESE TWO DAYS TO EXHIBIT THE BEST STRONG TO SEVERE THUNDERSTORM POTENTIAL. THE FRONTAL BOUNDARY WILL FINALLY MOVE OUT OF THE REGION BY SUNDAY AFTERNOON AS WE HEAD INTO THE MORE AMPLIFIED TROUGHING PATTERN ACROSS THE EASTERN CONUS. JUST AS THE UPPER LEVEL HEIGHTS WILL BE FALLING THROUGHOUT THE WEEKEND...SO TOO WILL THE TEMPERATURES. LOW 80S ARE EXPECTED FOR SATURDAY AND SUNDAY...AND SHOULD CONTINUE INTO THE FIRST PART OF THE WORK WEEK. UNFORTUNATELY...THOUGH THE COLD FRONT WOULD HAVE SHIFTED WELL TO OUR EAST MONDAY...WILL GENERATE ENOUGH MOISTURE AND INSTABILITY THAT AFTERNOON SHOWERS AND THUNDERSTORMS COULD SPREAD AS FAR WESTWARD AS EASTERN KY DURING THE AFTERNOON. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 222 AM EDT TUE JUN 23 2015 OUTSIDE OF SOME PATCHY VALLEY FOG IN THE EASTERN VALLEYS TONIGHT...VFR CONDITIONS SHOULD PREVAIL THROUGH MUCH OF THE PERIOD. SOME THUNDERSTORMS MAY DEVELOP ALONG AN APPROACHING COLD FRONT LATER THIS AFTERNOON AND EVENING. COVERAGE IS STILL UNCERTAIN AT THIS TIME...BUT WILL INTRODUCE SOME VCTS TO PROVIDE A WINDOW OF OPPORTUNITY FOR CONVECTION LATER TODAY. AS THE FRONT PASSES TONIGHT...COOLER AIR WILL FILTER INTO THE REGION...BUT MOISTURE MAY LINGER A BIT LONGER WHICH COULD SET THE STAGE FOR SOME DENSE FOG TONIGHT. THIS WILL HAVE THE POTENTIAL TO DROP CIGS OR VISIBILITIES BELOW AIRPORT MINIMUMS LATE TUESDAY NIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...RAY LONG TERM...JMW AVIATION...KAS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
109 AM EDT Tue Jun 23 2015 ...Updated Aviation Discussion... ...Forecast Update... Updated at 905 PM EDT Mon Jun 22 2015 Forecast is on track for the overnight period. Cirrus from convection upstream and earlier today will remain overhead. Complex of storms currently in southern/southeast Iowa will nose dive southward and is expected to weaken before approaching the area but likely to bring more cirrus for the overnight and morning hours. It may lay out an outflow boundary which could be the focus for thunderstorm development tomorrow. .SHORT TERM (Now through Tuesday Night)... Updated at 300 PM EDT Mon Jun 22 2015 ...Strong to Severe Storms Possible Tuesday Afternoon... Thunderstorms to our north in Michigan are sending plenty of subsiding cirrus our way this afternoon. Visible satellite imagery indicates our cumulus field is being held at bay because of this flow aloft, and latest radar over western KY shows earlier cells are decaying as well. Cannot rule out an isolated shower surviving in our southwest. Latest HRRR indicates a line of storms would fire in southeast Iowa/northern Illinois and head southeast through the evening, perhaps getting to our area as just a line of gusty winds or even a very isolated shower by daybreak Tuesday. Would expect wherever this boundary sets up to be the focus for further convection by late morning or early afternoon Tuesday. NAM soundings are very unstable for the afternoon, and surface temp/dewpoints are in line with what we expect tomorrow. Soundings show a layer of dry air in the 600-700 mb range, allowing the chance for both larger hail and stronger downburst winds. Bust potential for this forecast would be just how many clouds remain from the line that comes through overnight and how this affects surface temperatures. Clouds over LEX this hour are keeping temperatures ~5 degrees cooler than areas in the clear! Will highlight potential for severe wind gusts and hail in the stronger storms with our hazardous weather outlook. Again, highs Tuesday will depend greatly on extent of clouds in the morning. Based on current forecast, expect highs around 90. This should push heat indices into the mid to upper 90s for most locations. The best chance to get up to around 100 would be south of the I-64 corridor and west of a Bardstown to Glasgow line. .LONG TERM (Wednesday through Monday)... Issued at 300 PM EDT Mon Jun 22 2015 The synoptic pattern at the start of the long term period will feature an expansive ridge across the southern CONUS, placing the Ohio Valley on the periphery of the swift northwest flow found across much of the northern CONUS. This regime will amplify through the end of the long term period as the southern ridge breaks down and a trough builds into the Ohio Valley, bringing some relief from the precip chances and the hot and humid weather we`ve experienced as of late. Generally low-resolution synoptic models are notorious for struggling with convection and MCS development, so confidence in the long term period on timing and convective coverage is generally low, especially Wednesday. That being said, have attempted to best time the convection using a general model blend and ensemble data. This method brings just chance pops to the region Wednesday into Wednesday night, as there does not appear to be any substantial triggering PV anomaly to spark convection. By Thursday, the southern ridge will begin to break down as a strong trough dives into the northern CONUS. Timing as of now keeps much of the convection just north of the region through much of the daylight hours on Thursday. Good southwesterly flow ahead of an area of low pressure coupled with some expected sunshine and 850mb temps rising to around 20C means Thursday could end up being quite warm, assuming clouds/precip remain to the north. Have gone with highs in the low to mid 90s, which coupled with dewpoints in the low to mid 70s, will push heat index values on either side of 100 degrees. The trough and associated surface front will slowly push through the region Thursday night into Friday night. Mid-level flow will be sufficient to support some strong/severe storms, but the potential for storms Thursday night may hinder destabilization on Friday given the expected cloud cover. If we are able to see some sun break out on Friday, then a few strong/severe storms will be possible. Again, predictability in the mesoscale details at this timeframe are rather low, but the strength of the system pushing through does support the potential for some strong/severe storm development, especially across southern KY on Friday. Given the slow movement of the front through the area, we could also have some local flooding issues as well, so that will be something to continue to monitor. The passing cold front and building trough aloft will make for rather pleasant conditions moving in by the weekend. Temperatures will fall into the upper 70s and lower 80s for highs on Saturday and Sunday. Conditions should be generally dry Saturday night through Sunday, as the deeper moisture finally gets shunted to the east with the passing cold front. && .AVIATION (06Z TAF Update)... Updated at 106 AM EDT Tue Jun 23 2015 VFR conditions are expected through the remainder of the night with winds out of the SW and cirrus streaming across the region. For today the atmosphere will become unstable with the daytime heating and a cold front will approach from the north. Scattered thunderstorms will develop either along this front or residual outflow boundaries or both. Will continue the mention of thunderstorms through the afternoon hours in all TAF sites. Winds will shift a bit more to the west this morning with sustained winds in the 10-14 knot range through the day. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........ZT Short Term.....RJS Long Term......KJD Aviation.......EER
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
455 AM EDT TUE JUN 23 2015 .SYNOPSIS... CROSSING COLD FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE STRONG TO SEVERE...ON TUESDAY. HIGH PRESSURE RETURNS WEDNESDAY. && .NEAR TERM /THROUGH WEDNESDAY/... A FAIRLY COMPLICATED NEAR TERM SCENARIO SEEMS SET TO PLAY OUT OVER THE NEXT 24 HOURS ACROSS THE UPPER OHIO VALLEY AS ONGOING CONVECTION TO OUR NORTH AND WEST PLAY A ROLE IN THE MORNING FORECAST...WHILE THE EVOLUTION OF SAID CONVECTION...ITS BLOW OFF...AND DEBRIS...HAVE LARGE RAMIFICATIONS UPON THE EVENTUAL DEVELOPMENT OR LACK THEROF AHEAD OF A COLD FRONT AS IT SLICES THROUGH THE AREA LATER TODAY...BRING A WHOLESALE AIR MASS CHANGE IN OUR REGION. LET`S TRY TO BREAK THIS DOWN... MODEL TRENDS HAVE FAVORED IMPRESSIVE CONVECTIVE DEVELOPMENT OVER THE CENTRAL GREAT LAKES THROUGH EARLY THIS MORNING FOR SEVERAL DAYS...AND BOY HAS THE CONVECTION REALLY GOTTEN ROLLING OVERNIGHT. HOWEVER...CONVECTIVE TRENDS...MODEL SOUNDINGS...AND TRENDS IN LIGHTNING DATA SUGGEST THIS CONVECTION IS BECOMING LESS FIERCE AS IT MOVES OFF OF LAKE ERIE. THIS ACTIVITY IS LARGELY ANCHORED TO UPEPR FORCING...WHICH IS TRENDING EASTWARD...HOWEVER INDIVIDUAL CONVECTIVE VORTS ARE ALLOWING FOR SOME SOUTHWARD PROPAGATION OF THE LINE AT THE MOMENT. THIS WILL ALLOW STORMS OVER NORTHERN OHIO TO TREND TOWARD I-80 OVER THE NEXT COUPLE OF HOURS...EVEN WHILE THE BULK OF THE FORCING TRANSLATES TO THE EAST GENERALLY NORTH OF THE AREA. WHILE THE BULK OF THE UPPER FORCING MOVES EASTWARD...WEAK SHORT WAVE TROUGHING DOES SEEM POISED TO DROP THROUGH THE CWA THIS MORNING PER MODEL GUIDANCE. GIVEN THE AIR MASS...IT SEEMS UNLIKELY THIS WOULD ENTIRELY DISSIPATE...HOWEVER THE BOUNDARY LAYER IS NOT ENTIRELY FAVORABLE FOR STRONG DOWNWARD MIXING POTENTIAL...SO IT WOULD SEEM ELEVATED CONVECTION WILL BE THE MAIN PROBLEM. ADDITIONALLY...GIVEN PROGRESSIVE FORCING...RAINFALL SHOULD BE PROGRESSIVE...WHICH WILL MINIMIZE FLOODING CONCERNS THROUGH MORNING. MODEL SOLUTIONS FAVOR INITIAL ACTIVITY DEPARTING OUR AREA BY LATE MORNING/EARLY AFTERNOON. HOWEVER...A QUICK GLANCE AT REGIONAL OBSERVATIONS REVEALS THAT ONGOING CONVECTION IS LARGELY UNTIED TO THE MAIN FRONTAL BOUNDARY OVER MICHIGAN AND NORTHERN ILLINOIS. LARGER SCALE MODELS SEEM TO TRY TO TIE THESE TWO THINGS TOGETHER RATHER QUICKLY ON TODAY...HOWEVER THE FINER SCALE MODELS MAINTAIN A DISTINCTION BETWEEN THE TWO. THE NAM IN PARTICULAR HAS BEEN INSISTENT ON THIS FOR SEVERAL RUNS...AND EVEN THE HRRR FAVORS CONVECTIVE REDEVELOPMENT THIS AFTERNOON. OBSERVATIONS REALLY DO NOT FAVOR THE FRONT CATCHING UP TO ONGOING CONVECTION THIS MORNING IN ANY FASHION...SO THE FORECAST STILL HEAVILY FAVORS REDEVELOPMENT AHEAD OF SAID FRONT THIS AFTERNOON. THIS BRINGS A WHOLE HOST OF PROBLEMS WITH IT. BULK SHEAR VALUES OF 45-50 KTS WITH SOME MODEST VEERING IS EVIDENT ON NAM SOUNDINGS AHEAD OF THE FRONT. ADDITIONALLY...MODEL PWATS SURGE TOWARD AND ABOVE 2 INCHES ALONG THE FRONT WITH CAPE VALUES JUMPING TOWARD 2000 J/KG. THIS IS EVEN WITHOUT A STRONG SIGNAL FOR CLEARING AHEAD OF THE FRONT. THAT SAID...SPC IS MAINTAINING THE SLIGHT RISK FOR SEVERE THUNDERSTORMS...WHICH SEEMS WARRANTED. THE MAIN THREAT DOES SEEM LIKELY TO BE DAMAGING WINDS...HOWEVER A SPINNER OR TWO CANNOT BE RULED OUT GIVEN THE LOW LEVEL WIND FIELD THAT SEEMS LIKELY TO BE CHARACTERISTIC OF THE PRE-FRONTAL ENVIRONMENT. IN MUST BE NOTED...HOWEVER...THAT GFS/SREF SOLUTIONS FAVOR THE FASTER FRONTAL MOVEMENT AND LACK OF DEEP CONVECTIVE REDEVELOPMENT. BUT GIVEN THAT "THE TREND IS YOUR FRIEND"...THEY HAVE LARGELY BEEN CONSIDERED THE LESS LIKELY SCENARIOS. GIVEN A VERY WARM START TO THE DAY TODAY...AND STRONG MIXING LIKELY...HIGHS SHOULD EASILY JUMP INTO THE 80S...MAKING THOSE 2000 J/KG CAPE VALUES EASY TO ATTAIN...EVEN WITHOUT STRONG ISOLATION. MODEL AGREEMENT INCREASES GREATLY BEHIND THE FRONT...AS PWATS FALL OFF A CLIFF AND LAYER RH VALUES DO LIKEWISE. POPS RAPIDLY WILL FALL TO NEAR ZERO IN THE POST-FRONTAL ENVIRONMENT...AND DEWPOINTS WILL LIKELY FALL OFF A CLIFF AS WELL. THIS WILL YIELD A SUBSTANTIALLY NICER TUESDAY NIGHT AND WEDNESDAY AS THE SOUP WE HAVE BECOME ACCUSTOMED TO FINALLY DEPARTS FOR AT LEAST A BRIEF INTERLUDE. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... SURFACE HIGH PRESSURE WILL KEEP CONDITIONS DRY WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BUT ZONAL FLOW ALOFT MEANS TRANQUIL WEATHER WILL BE FLEETING. A MID-LEVEL WAVE...ASSOCIATED WITH CONVECTION OVER THE CORNBELT...WILL APPROACH THE GREAT LAKES BY DAY BREAK THURSDAY. REMNANTS OF THE EARLIER CONVECTION WILL APPROACH THE FORECAST AREA DURING A CLIMATOLOGICALLY UNFAVORABLE TIME...AND SHOULD BE DISSIPATING ON ENTRANCE. THURSDAY AFTERNOON SHOULD BRING A RE-INVIGORATION OF SHOWERS AND THUNDERSTORMS ALONG THE NOSE OF THE LOW. IMPRESSIVE SHEAR VALUES WILL EXIST ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA...NEAR THE BASE OF THE WAVE. HOWEVER...REMNANT CLOUD COVER WILL QUELL THE MORNING WARM-UP AND SERVE TO STABILIZE A MAJORITY OF THE FORECAST AREA...DESPITE STEEPENING MID-LEVEL LAPSE RATES AS COOL AIR ALOFT MOVES IN. THE SOUTHERN PERIPHERY OF THE FORECAST AREA WILL HAVE THE BEST CHANCE TO HOLD SOME SUN...AND THUS THE BETTER OPPORTUNITY TO DESTABILIZE. IF ANY STRONG TO SEVERE STORMS WERE TO EXIST THURSDAY EVENING...THIS IS WHERE THEY WILL RESIDE. FRIDAY THE UPPER-LEVEL FLOW FLATTENS WEST TO EAST AND THE WEAK SURFACE LOW STAGNATES OVER THE OHIO RIVER VALLEY. THE RESULT IS THAT MOISTURE NEVER CLEARS THE SOUTHERN 1/2 OF THE FORECAST AREA...KEEPING RAIN CHANCES HIGHER THROUGH FRIDAY EVENING WITH ANOTHER AFTERNOON FLARE-UP OF CONVECTION OVER THE HIGH TERRAIN OF PA/WV/MD. TAX && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AN UPPER-LEVEL WAVE PASSING THROUGH THE WESTERN GREAT LAKES FRIDAY NIGHT WILL SERVE TO AMPLIFY THE MERIDIONAL FLOW PATTERN. PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL LINGER...MAINLY ACROSS OUR SOUTH. BY THE MIDDLE PART OF THE WEEKEND THE EASTERN CONUS TROF IS IN FULL EFFECT WITH INCREASED CLOUD COVER RESULTING IN MODERATED TEMPERATURE READINGS. GUIDANCE DIFFERS A BIT ON THE EXACT EVOLUTION OF THE UPPER-LEVEL TROF...WITH THE WETTER GFS CUTTING OFF THE LOW DIRECTLY OVERHEAD. REGARDLESS OF THE MINUTIAE...IT APPEARS AS TROF WILL BE HERE TO STAY AS A RE-ENFORCING WAVE WILL DIVE IN FROM THE NORTHWEST BY EARLY NEXT WEEK. TAX && .AVIATION /09Z TUESDAY THROUGH SATURDAY/... GENERAL VFR CONDITIONS ARE EXPECTED MUCH OF THE NIGHT. A FEW SHOWERS/STORMS COULD MOVE INTO NW PA BY EARLY MORNING...SO INCLUDED A TEMPO MENTION OF THIS FOR FKL AND DUJ. A LOW LEVEL JET IS PROGGED ACROSS THE REGION EARLY THIS MORNING PRODUCING LLWS...AND THIS WAS ALSO INCLUDED IN THE TAFS. ADDITIONAL SHOWERS/STORMS ARE EXPECTED TUESDAY AS A COLD FRONT ADVANCES ACROSS THE REGION. LOW CONFIDENCE IN TIMING OF ANY PRECIP AND HOW MORNING CLOUDS/PRECIP COULD IMPACT THUNDERSTORM REDEVELOPMENT...SO MAINTAINED A GENERAL VCSH/VCTS MENTION IN MOST OF THE TAFS UNTIL TIMING CAN BE BETTER DETERMINED. .OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE POSSIBLE BY LATE WEEK WITH CROSSING LOW PRESSURE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
404 AM EDT TUE JUN 23 2015 .SYNOPSIS... CROSSING COLD FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE STRONG TO SEVERE...ON TUESDAY. HIGH PRESSURE RETURNS WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... A FAIRLY COMPLICATED NEAR TERM SCENARIO SEEMS SET TO PLAY OUT OVER THE NEXT 24 HOURS ACROSS THE UPPER OHIO VALLEY AS ONGOING CONVECTION TO OUR NORTH AND WEST PLAY A ROLE IN THE MORNING FORECAST...WHILE THE EVOLUTION OF SAID CONVECTION...ITS BLOW OFF...AND DEBRIS...HAVE LARGE RAMIFICATIONS UPON THE EVENTUAL DEVELOPMENT OR LACK THEROF AHEAD OF A COLD FRONT AS IT SLICES THROUGH THE AREA LATER TODAY...BRING A WHOLESALE AIR MASS CHANGE IN OUR REGION. LET`S TRY TO BREAK THIS DOWN... MODEL TRENDS HAVE FAVORED IMPRESSIVE CONVECTIVE DEVELOPMENT OVER THE CENTRAL GREAT LAKES OVERNIGHT INTO EARLY THIS MORNING FOR SEVERAL DAYS...AND BOY HAS THE CONVECTION REALLY GOTTEN ROLLING OVERNIGHT. HOWEVER...CONVECTIVE TRENDS AND MODEL SOUNDINGS ALL SUGGEST THIS CONVECTION IS BECOMING LESS AND LESS ATTACHED TO THE SURFACE. AS A RESULT...IT WOULD SEEM THE CONVECTION THAT IS ONGOING SHOULD START TO FOLLOW THE DEEPER MID-LEVEL INSTABILITY AND SYNOPTIC SCALE FORCING FOR ASCENT. AS A RESULT...THE CONVECTION OVER MICHIGAN SEEMS LIKELY TO CONTINUE ITS TREND OF TRACKING EASTWARD...WHICH WILL LEAVE IT LARGELY NORTH OF I-80. THIS MEANS ACTIVITY OVER INDIANA WILL BE OUR PROBLEM CHILD. THERE HAD BEEN SOME CONCERN EARLIER THAT IT WOULD DEVELOP A BIT MORE THAN IT HAS...HOWEVER INTERACTION WITH THE LAKE BREEZE SOUTHEAST OF LAKE MICHIGAN WAS FAR FROM IMPRESSIVE LAST EVENING...RESULTING IN MEDIOCRE ONGOING ACTIVITY AT THIS JUNCTURE. HOWEVER...MID-LEVEL FORCING ASSOCIATED WITH THIS WEAK CONVECTION DOES PROPAGATE DOWNSTREAM OVERNIGHT TOWARD MORNING INTO AND ACROSS OUR AREA. GIVEN THE AIR MASS...IT SEEMS UNLIKELY THIS WOULD ENTIRELY DISSIPATE...HOWEVER DECOUPLING HAS ALREADY OCCURRED OVER MUCH OF OUR AREA...SO IT WOULD SEEM ELEVATED CONVECTION WILL BE THE MAIN PROBLEM. ADDITIONALLY...GIVEN PROGRESSIVE FORCING...RAINFALL SHOULD BE PROGRESSIVE...WHICH WILL MINIMIZE FLOODING CONCERNS THROUGH MORNING. MODEL SOLUTIONS FAVOR INITIAL ACTIVITY DEPARTING OUR AREA BY LATE MORNING/EARLY AFTERNOON. HOWEVER...A QUICK GLANCE AT REGIONAL OBSERVATIONS REVEALS THAT ONGOING CONVECTION IS LARGELY UNTIED TO THE SURFACE BOUNDARY AND CHANGE OF AIR MASS THAT IS READILY APPARENT OVER CENTRAL WISCONSIN. LARGER SCALE MODELS SEEM TO TRY TO TIE THESE TWO THINGS TOGETHER RATHER QUICKLY ON TUESDAY...HOWEVER THE FINER SCALE MODELS MAINTAIN A DISTINCTION BETWEEN THE TWO. THE NAM IN PARTICULAR HAS BEEN INSISTENT ON THIS FOR SEVERAL RUNS...AND EVEN THE HRRR FAVORS CONVECTIVE REDEVELOPMENT THIS AFTERNOON. OBSERVATIONS REALLY DO NOT FAVOR THE FRONT CATCHING UP TO ONGOING CONVECTION THIS MORNING IN ANY FASHION...SO THE FORECAST STILL HEAVILY FAVORS REDEVELOPMENT AHEAD OF SAID FRONT THIS AFTERNOON. THIS BRINGS A WHOLE HOST OF PROBLEMS WITH IT. BULK SHEAR VALUES OF 45-50 KTS WITH SOME MODEST VEERING IS EVIDENT ON NAM SOUNDINGS AHEAD OF THE FRONT. ADDITIONALLY...MODEL PWATS SURGE TOWARD AND ABOVE 2 INCHES ALONG THE FRONT WITH CAPE VALUES JUMPING TOWARD 2000 J/KG. THIS IS EVEN WITHOUT A STRONG SIGNAL FOR CLEARING AHEAD OF THE FRONT. THAT SAID...SPC IS MAINTAINING THE SLIGHT RISK FOR SEVERE THUNDERSTORMS...WHICH SEEMS WARRANTED. THE MAIN THREAT DOES SEEM LIKELY TO BE DAMAGING WINDS...HOWEVER A SPINNER OR TWO CANNOT BE RULED OUT GIVEN THE LOW LEVEL WIND FIELD THAT SEEMS LIKELY TO BE CHARACTERISTIC OF THE PRE-FRONTAL ENVIRONMENT. IN MUST BE NOTED...HOWEVER...THAT GFS/SREF SOLUTIONS FAVOR THE FASTER FRONTAL MOVEMENT AND LACK OF DEEP CONVECTIVE REDEVELOPMENT. BUT GIVEN THAT "THE TREND IS YOUR FRIEND"...THEY HAVE LARGELY BEEN CONSIDERED THE LESS LIKELY SCENARIOS. GIVEN A VERY WARM START TO THE DAY TODAY...AND STRONG MIXING LIKELY...HIGHS SHOULD EASILY JUMP INTO THE 80S...MAKING THOSE 2000 J/KG CAPE VALUES EASY TO ATTAIN...EVEN WITHOUT STRONG ISOLATION. MODEL AGREEMENT INCREASES GREATLY BEHIND THE FRONT...AS PWATS FALL OFF A CLIFF AND LAYER RH VALUES DO LIKEWISE. POPS RAPIDLY WILL FALL TO NEAR ZERO IN THE POST-FRONTAL ENVIRONMENT...AND DEWPOINTS WILL LIKELY FALL OFF A CLIFF AS WELL. THIS WILL YIELD A SUBSTANTIALLY NICER TUESDAY NIGHT AND WEDNESDAY AS THE SOUP WE HAVE BECOME ACCUSTOMED TO FINALLY DEPARTS FOR AT LEAST A BRIEF INTERLUDE. FRIES && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... SURFACE HIGH PRESSURE WILL KEEP CONDITIONS DRY WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BUT ZONAL FLOW ALOFT MEANS TRANQUIL WEATHER WILL BE FLEETING. A MID-LEVEL WAVE...ASSOCIATED WITH CONVECTION OVER THE CORNBELT...WILL APPROACH THE GREAT LAKES BY DAY BREAK THURSDAY. REMNANTS OF THE EARLIER CONVECTION WILL APPROACH THE FORECAST AREA DURING A CLIMATOLOGICALLY UNFAVORABLE TIME...AND SHOULD BE DISSIPATING ON ENTRANCE. THURSDAY AFTERNOON SHOULD BRING A RE-INVIGORATION OF SHOWERS AND THUNDERSTORMS ALONG THE NOSE OF THE LOW. IMPRESSIVE SHEAR VALUES WILL EXIST ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA...NEAR THE BASE OF THE WAVE. HOWEVER...REMNANT CLOUD COVER WILL QUELL THE MORNING WARM-UP AND SERVE TO STABILIZE A MAJORITY OF THE FORECAST AREA...DESPITE STEEPENING MID-LEVEL LAPSE RATES AS COOL AIR ALOFT MOVES IN. THE SOUTHERN PERIPHERY OF THE FORECAST AREA WILL HAVE THE BEST CHANCE TO HOLD SOME SUN...AND THUS THE BETTER OPPORTUNITY TO DESTABILIZE. IF ANY STRONG TO SEVERE STORMS WERE TO EXIST THURSDAY EVENING...THIS IS WHERE THEY WILL RESIDE. FRIDAY THE UPPER-LEVEL FLOW FLATTENS WEST TO EAST AND THE WEAK SURFACE LOW STAGNATES OVER THE OHIO RIVER VALLEY. THE RESULT IS THAT MOISTURE NEVER CLEARS THE SOUTHERN 1/2 OF THE FORECAST AREA...KEEPING RAIN CHANCES HIGHER THROUGH FRIDAY EVENING WITH ANOTHER AFTERNOON FLARE-UP OF CONVECTION OVER THE HIGH TERRAIN OF PA/WV/MD. TAX && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AN UPPER-LEVEL WAVE PASSING THROUGH THE WESTERN GREAT LAKES FRIDAY NIGHT WILL SERVE TO AMPLIFY THE MERIDIONAL FLOW PATTERN. PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL LINGER...MAINLY ACROSS OUR SOUTH. BY THE MIDDLE PART OF THE WEEKEND THE EASTERN CONUS TROF IS IN FULL EFFECT WITH INCREASED CLOUD COVER RESULTING IN MODERATED TEMPERATURE READINGS. GUIDANCE DIFFERS A BIT ON THE EXACT EVOLUTION OF THE UPPER-LEVEL TROF...WITH THE WETTER GFS CUTTING OFF THE LOW DIRECTLY OVERHEAD. REGARDLESS OF THE MINUTIAE...IT APPEARS AS TROF WILL BE HERE TO STAY AS A RE-ENFORCING WAVE WILL DIVE IN FROM THE NORTHWEST BY EARLY NEXT WEEK. TAX && .AVIATION /08Z TUESDAY THROUGH SATURDAY/... GENERAL VFR CONDITIONS ARE EXPECTED MUCH OF THE NIGHT. A FEW SHOWERS/STORMS COULD MOVE INTO NW PA BY EARLY MORNING...SO INCLUDED A TEMPO MENTION OF THIS FOR FKL AND DUJ. A LOW LEVEL JET IS PROGGED ACROSS THE REGION EARLY THIS MORNING PRODUCING LLWS...AND THIS WAS ALSO INCLUDED IN THE TAFS. ADDITIONAL SHOWERS/STORMS ARE EXPECTED TUESDAY AS A COLD FRONT ADVANCES ACROSS THE REGION. LOW CONFIDENCE IN TIMING OF ANY PRECIP AND HOW MORNING CLOUDS/PRECIP COULD IMPACT THUNDERSTORM REDEVELOPMENT...SO MAINTAINED A GENERAL VCSH/VCTS MENTION IN MOST OF THE TAFS UNTIL TIMING CAN BE BETTER DETERMINED. .OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE POSSIBLE BY LATE WEEK WITH CROSSING LOW PRESSURE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
133 AM EDT TUE JUN 23 2015 .SYNOPSIS... CROSSING COLD FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE STRONG TO SEVERE...ON TUESDAY. HIGH PRESSURE RETURNS WEDNESDAY. && .NEAR TERM /THROUGH TODAY/... A FAIRLY COMPLICATED NEAR TERM SCENARIO SEEMS SET TO PLAY OUT OVER THE NEXT 24 HOURS ACROSS THE UPPER OHIO VALLEY AS ONGOING CONVECTION TO OUR NORTH AND WEST PLAY A ROLE IN THE MORNING FORECAST...WHILE THE EVOLUTION OF SAID CONVECTION...ITS BLOW OFF...AND DEBRIS...HAVE LARGE RAMIFICATIONS UPON THE EVENTUAL DEVELOPMENT OR LACK THEROF AHEAD OF A COLD FRONT AS IT SLICES THROUGH THE AREA LATER TODAY...BRING A WHOLESALE AIR MASS CHANGE IN OUR REGION. LET`S TRY TO BREAK THIS DOWN... MODEL TRENDS HAVE FAVORED IMPRESSIVE CONVECTIVE DEVELOPMENT OVER THE CENTRAL GREAT LAKES OVERNIGHT INTO EARLY THIS MORNING FOR SEVERAL DAYS...AND BOY HAS THE CONVECTION REALLY GOTTEN ROLLING OVERNIGHT. HOWEVER...CONVECTIVE TRENDS AND MODEL SOUNDINGS ALL SUGGEST THIS CONVECTION IS BECOMING LESS AND LESS ATTACHED TO THE SURFACE. AS A RESULT...IT WOULD SEEM THE CONVECTION THAT IS ONGOING SHOULD START TO FOLLOW THE DEEPER MID-LEVEL INSTABILITY AND SYNOPTIC SCALE FORCING FOR ASCENT. AS A RESULT...THE CONVECTION OVER MICHIGAN SEEMS LIKELY TO CONTINUE ITS TREND OF TRACKING EASTWARD...WHICH WILL LEAVE IT LARGELY NORTH OF I-80. THIS MEANS ACTIVITY OVER INDIANA WILL BE OUR PROBLEM CHILD. THERE HAD BEEN SOME CONCERN EARLIER THAT IT WOULD DEVELOP A BIT MORE THAN IT HAS...HOWEVER INTERACTION WITH THE LAKE BREEZE SOUTHEAST OF LAKE MICHIGAN WAS FAR FROM IMPRESSIVE LAST EVENING...RESULTING IN MEDIOCRE ONGOING ACTIVITY AT THIS JUNCTURE. HOWEVER...MID-LEVEL FORCING ASSOCIATED WITH THIS WEAK CONVECTION DOES PROPAGATE DOWNSTREAM OVERNIGHT TOWARD MORNING INTO AND ACROSS OUR AREA. GIVEN THE AIR MASS...IT SEEMS UNLIKELY THIS WOULD ENTIRELY DISSIPATE...HOWEVER DECOUPLING HAS ALREADY OCCURRED OVER MUCH OF OUR AREA...SO IT WOULD SEEM ELEVATED CONVECTION WILL BE THE MAIN PROBLEM. ADDITIONALLY...GIVEN PROGRESSIVE FORCING...RAINFALL SHOULD BE PROGRESSIVE...WHICH WILL MINIMIZE FLOODING CONCERNS THROUGH MORNING. MODEL SOLUTIONS FAVOR INITIAL ACTIVITY DEPARTING OUR AREA BY LATE MORNING/EARLY AFTERNOON. HOWEVER...A QUICK GLANCE AT REGIONAL OBSERVATIONS REVEALS THAT ONGOING CONVECTION IS LARGELY UNTIED TO THE SURFACE BOUNDARY AND CHANGE OF AIR MASS THAT IS READILY APPARENT OVER CENTRAL WISCONSIN. LARGER SCALE MODELS SEEM TO TRY TO TIE THESE TWO THINGS TOGETHER RATHER QUICKLY ON TUESDAY...HOWEVER THE FINER SCALE MODELS MAINTAIN A DISTINCTION BETWEEN THE TWO. THE NAM IN PARTICULAR HAS BEEN INSISTENT ON THIS FOR SEVERAL RUNS...AND EVEN THE HRRR FAVORS CONVECTIVE REDEVELOPMENT THIS AFTERNOON. OBSERVATIONS REALLY DO NOT FAVOR THE FRONT CATCHING UP TO ONGOING CONVECTION THIS MORNING IN ANY FASHION...SO THE FORECAST STILL HEAVILY FAVORS REDEVELOPMENT AHEAD OF SAID FRONT THIS AFTERNOON. THIS BRINGS A WHOLE HOST OF PROBLEMS WITH IT. BULK SHEAR VALUES OF 45-50 KTS WITH SOME MODEST VEERING IS EVIDENT ON NAM SOUNDINGS AHEAD OF THE FRONT. ADDITIONALLY...MODEL PWATS SURGE TOWARD AND ABOVE 2 INCHES ALONG THE FRONT WITH CAPE VALUES JUMPING TOWARD 2000 J/KG. THIS IS EVEN WITHOUT A STRONG SIGNAL FOR CLEARING AHEAD OF THE FRONT. THAT SAID...SPC IS MAINTAINING THE SLIGHT RISK FOR SEVERE THUNDERSTORMS...WHICH SEEMS WARRANTED. THE MAIN THREAT DOES SEEM LIKELY TO BE DAMAGING WINDS...HOWEVER A SPINNER OR TWO CANNOT BE RULED OUT GIVEN THE LOW LEVEL WIND FIELD THAT SEEMS LIKELY TO BE CHARACTERISTIC OF THE PRE-FRONTAL ENVIRONMENT. IN MUST BE NOTED...HOWEVER...THAT GFS/SREF SOLUTIONS FAVOR THE FASTER FRONTAL MOVEMENT AND LACK OF DEEP CONVECTIVE REDEVELOPMENT. BUT GIVEN THAT "THE TREND IS YOUR FRIEND"...THEY HAVE LARGELY BEEN CONSIDERED THE LESS LIKELY SCENARIOS. GIVEN A VERY WARM START TO THE DAY TODAY...AND STRONG MIXING LIKELY...HIGHS SHOULD EASILY JUMP INTO THE 80S...MAKING THOSE 2000 J/KG CAPE VALUES EASY TO ATTAIN...EVEN WITHOUT STRONG ISOLATION. MODEL AGREEMENT INCREASES GREATLY BEHIND THE FRONT...AS PWATS FALL OFF A CLIFF AND LAYER RH VALUES DO LIKEWISE. POPS RAPIDLY WILL FALL TO NEAR ZERO IN THE POST-FRONTAL ENVIRONMENT...AND DEWPOINTS WILL LIKELY FALL OFF A CLIFF AS WELL. THIS WILL YIELD A SUBSTANTIALLY NICER TUESDAY NIGHT AND WEDNESDAY AS THE SOUP WE HAVE BECOME ACCUSTOMED TO FINALLY DEPARTS FOR AT LEAST A BRIEF INTERLUDE. FRIES && .SHORT TERM /TONIGHT THROUGH THURSDAY/... COLD FRONT WILL PUSH SOUTH OF THE REGION OVERNIGHT TUESDAY...WITH HIGH PRESSURE BUILDING ON IT`S HEELS FOR WEDNESDAY. STRONG SUBSIDENCE SHOULD KEEP SKIES MOSTLY SUNNY DESPITE NW FLOW AND TEMPERATURES SHOULD MODERATE TO NEAR NORMAL VALUES. WEAK TROUGHING/NW FLOW WILL SUPPORT FAST MOVING SHORTWAVES IN THE MID-UPPER LEVELS WITH THE NEXT SYSTEM PROGGED FOR THURSDAY. ALL THE MODELS...TO ONE DEGREE OR ANOTHER...HAVE THIS WAVE APPROACHING BY LATE THURSDAY AFTERNOON. SOUTHERLY FLOW AHEAD OF IT SHOULD BRING A RETURN OF THE WARM...MOIST...AIRMASS TO SUPPORT FURTHER DESTABILIZATION DEPENDING ON CLOUD COVER. STRENGTHENING LOW AND MID LEVEL JETS WILL SUPPORT STRONG SHEAR AS THE LOW MOVES ACROSS THE REGION...IF THE STRONGER GFS IS CORRECT. WITH ALL OF THIS IN MIND...DID NOT FEEL THE NEED TO STRAY MUCH FROM THE PREVIOUS FORECAST...DESPITE SOME SLIGHT TEMPORAL AND SPACIAL CHANGES FROM RUN TO RUN. TEMPERATURES WERE ADJUSTED ONLY SLIGHTLY...WITH CLOUD COVER EXPECTED TO KEEP HIGHS A BIT LOWER OVER THE NORTHERN ZONES. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... BY THE WEEKEND...THE UPPER-LEVEL PATTERN QUICKLY SHIFTS TO MERIDIONAL AS A STOUT RIDGE BUILDS NEAR THE FOUR CORNERS REGION OF THE DESERT SOUTHWEST...AND A LARGE TROF DEEPENS EAST OF THE MISSISSIPPI. WITH THIS PATTERN IN PLACE...ALMOST-DAILY RAIN CHANCES WILL NOT BE OUT OF THE QUESTION...AND TEMPERATURES SHOULD HOLD JUST BELOW AVERAGES. && .AVIATION /04Z TUESDAY THROUGH SATURDAY/... GENERAL VFR CONDITIONS ARE EXPECTED MUCH OF THE NIGHT. A FEW SHOWERS/STORMS COULD MOVE INTO NW PA BY EARLY MORNING...SO INCLUDED A TEMPO MENTION OF THIS FOR FKL AND DUJ. A LOW LEVEL JET IS PROGGED ACROSS THE REGION EARLY THIS MORNING PRODUCING LLWS...AND THIS WAS ALSO INCLUDED IN THE TAFS. ADDITIONAL SHOWERS/STORMS ARE EXPECTED TUESDAY AS A COLD FRONT ADVANCES ACROSS THE REGION. LOW CONFIDENCE IN TIMING OF ANY PRECIP AND HOW MORNING CLOUDS/PRECIP COULD IMPACT THUNDERSTORM REDEVELOPMENT...SO MAINTAINED A GENERAL VCSH/VCTS MENTION IN MOST OF THE TAFS UNTIL TIMING CAN BE BETTER DETERMINED. .OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE POSSIBLE BY LATE WEEK WITH CROSSING LOW PRESSURE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EDT TUE JUN 23 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT TUE JUN 23 2015 WV IMAGERY AND RAP ANALYSIS CONTINUES TO INDICATE A ZONAL FLOW PATTERN ACROSS THE NRN CONUS. MAIN SHORTWAVE WHICH SUPPORTED THUNDERSTORMS ACROSS THE UPPER GREAT LAKES LAST EVENING HAS NOW LIFTED NE OF LAKE SUPERIOR. RESIDUAL LIGHT SHRA/DZ OVER CENTRAL UPPER MI EARLIER THIS MORNING FROM THIS FEATURE HAS NOW ENDED ...ALTHOUGH SOME STRATUS PRESENTLY STILL LINGERS OVER THE AREA. ALSO WNW WINDS REMAIN QUITE BREEZY (NEAR 30 MPH) OVER THE ERN HALF OF THE CWA AS COLD ADVECTION BEHIND THE SYSTEM ALLOWS FOR SOME MIXING OF STRONGER WINDS JUST OFF THE SFC. UPSTREAM SHORTWAVE OVER SRN MANITOBA IS PROGGED TO BRING IN SHRA TO THE AREA TONIGHT. TODAY...DRYING AND ASSOCIATED SUBSIDENCE FROM HIGH PRES BUILDING IN FROM THE UPPER MS VALLEY WILL CLEAR OUT LINGERING STRATUS THIS MORNING...YIELDING MOSTLY SUNNY SKIES WHILE WNW WINDS DIMINISH. TEMPS WILL BE NEAR SEASONAL AVERAGES...GENERALLY FROM THE LOWER TO MID 70S. TONIGHT...THE SHORTWAVE FROM SRN MANITOBA WILL MOVE ACROSS NRN LAKE SUPERIOR THIS EVENING AS FORCING ASSOC WITH THIS FEATURE GENERALLY STAYS NORTH OF UPPER MI. HAVE INTRODUCED SOME LOW CHC POPS FOR SHRA OVER LAKE SUPERIOR TONIGHT WITH SOME SLIGHT CHC POPS OVER NW UPPER MI AS A WEAK SFC TROUGH MOVES ACROSS THE REGION ALTHOUGH AVAILABLE MOISTURE WITH THIS SYSTEM WL BE LIMITED. EXPECT LOWS IN THE 50S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 328 AM EDT TUE JUN 23 2015 BEST CHANCES FOR PRECIP WILL BE INLAND FROM LAKE SUPERIOR WEDNESDAY THROUGH THU AS SHORTWAVE ENERGY MOVES THROUGH. BEST CHANCES WILL BE DURING THE DAY WED WITH DIURNAL HEATING AND WED NIGHT AS THE MAIN SHORTWAVE ENERGY MOVES THROUGH...ALTHOUGH THERE IS DISAGREEMENT BETWEEN MODELS. CAPE LOOKS FAIRLY LIMITED AT OR BELOW 500J/KG...SO WILL KEEP ONLY SLIGHT THUNDER CHANCES...BUT AMPLE MOISTURE AND SLOW STORM MOVEMENT DUE TO WEAK LOW LEVEL WINDS WILL ALLOW FOR THREAT OF SOME PROLONGED HEAVY RAIN ON WED. HOWEVER...RAINFALL AMOUNTS ARE STILL UNCERTAIN. ADDITIONAL SHORTWAVE ENERGY LOOKS TO MOVE THROUGH THU...BUT LATEST MODEL RUNS KEEP THAT FARTHER SW...SO THE BEST POPS ARE FOR AREAS ALONG THE WI BORDER. A SFC HIGH MOVES THROUGH THU NIGHT INTO SAT NIGHT...BRINGING MOSTLY DRY WEATHER AND DECREASED CLOUDINESS. MODELS SHOW A SHORTWAVE MOVING THROUGH THE AREA SUN INTO MON...WITH DISAGREEMENT ON TIMING...WHICH WILL BRING RAIN TO THE AREA AS IT PASSES. THE SHORTWAVES LOOK TO AMPLIFY AN UPPER TROUGH OVER THE GREAT LAKES...WHICH MAY STICK AROUND INTO EARLY JULY. TEMPERATURES THROUGH THE NEXT 7 DAYS LOOK TO BE NEAR OR JUST BELOW NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 120 AM EDT TUE JUN 23 2015 AFTER A FEW HOURS OF LINGERING IFR/LIFR CIGS AT KCMX...CONDITIONS ARE EXPECTED TO BE VFR FOR THIS FORECAST PERIOD AS DRIER AIR WORKS IN BEHIND THE FRONT. WILL CONTINUE GUSTY INTO THIS MORNING BEHIND THE COLD FRONT AND SHOULD GET GUSTY AT CMX AGAIN LATE TUE AFTERNOON WITH A WEST WIND. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT TUE JUN 23 2015 A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF A LOW LIFTING INTO QUEBEC TODAY WILL CONTINUE TO SUPPORT WNW 35 KNOT GALES EARLY THIS MORNING OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN ALLOW WINDS TO DIE DOWN BY MIDDAY AND KEEP WINDS LIGHT FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS MAY ALLOW PATCHY FOG TO LINGER OVER ERN LAKE SUPERIOR EARLY THIS MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 10 AM EDT THIS MORNING FOR LSZ266-267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...07 MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
328 AM EDT TUE JUN 23 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 418 PM EDT MON JUN 22 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE TROUGH FROM NW ONTARIO INTO NRN MN. THE RESIDUAL MCV GENERATED FROM THE LARGE MCS EARLIER TODAY WAS LOCATED NEAR NW LOWER MI. FORCING ASSOCIATED WITH THIS FEATURE AND 305K-310K ISENTROPIC ASCENT AHEAD OF THE SHRTWV SUPPORTED SOME SHRA OVER NRN UPPER MI. AT THE SFC...A COLD FRONT EXTENDED ACROSS ERN MN. SCT SHRA AND ISOLATED TS HAS ALSO DEVELOPED ALONG AND AHEAD OF THE FRONT WHERE HEIGHT FALLS AHEAD OF THE SHRTWV WERE MOVING IN. CLOUDS AND AREAS OF SHOWERS HAVE LIMITED HEATING/INSTABILITY WITH HIGHEST SB/MU CAPE VALUES ONLY UP TO AROUND 500 J/KG OVER THE WEST. EXPECT SCT SHRA/TSRA TO CONTINUE TO PUSH FROM NW WI THROUGH UPPER MI THIS EVENING. ALTHOUGH 0-6KM/0-1KM SHEAR VALUES OF 40-60KT/25-35KT WOULD BE FAVORABLE FOR SOME STRONG/SVR STORMS. EVEN WITH SOME ADDITIONAL CAPE RECOVERY...THE MARGINAL INSTABILITY WILL LIMIT THE SVR POTENTIAL. NEVERTHELESS...AN ISOLATED SVR STORM CANNOT BE RULED OUT. THE SCT SHRA/TSRA ARE EXPECTED TO MOVE OUT OF THE CNTRL AND EAST BTWN 03Z-06Z WITH DRY WEATHER THE REST OF THE NIGHT. GUSTY WINDS WILL DEVELOP BEHIND THE FRONT AND LOW PRES WITH THE PRES RISE MAX MOVING THROUGH THIS EVENING AND A TIGHT PRES GRADIENT LINGERING OVERNIGHT. TUE...HIGH PRES BUILDING FROM THE UPPER MS VALLEY INTO THE WRN GREAT LAKES WITH MUCH DRIER AIR WILL BRING MOSTLY SUNNY SKIES...BREEZY NW WINDS AND TEMPS NEAR SEASONAL AVERAGES FROM THE LOWER TO MID 70S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 328 AM EDT TUE JUN 23 2015 BEST CHANCES FOR PRECIP WILL BE INLAND FROM LAKE SUPERIOR WEDNESDAY THROUGH THU AS SHORTWAVE ENERGY MOVES THROUGH. BEST CHANCES WILL BE DURING THE DAY WED WITH DIURNAL HEATING AND WED NIGHT AS THE MAIN SHORTWAVE ENERGY MOVES THROUGH...ALTHOUGH THERE IS DISAGREEMENT BETWEEN MODELS. CAPE LOOKS FAIRLY LIMITED AT OR BELOW 500J/KG...SO WILL KEEP ONLY SLIGHT THUNDER CHANCES...BUT AMPLE MOISTURE AND SLOW STORM MOVEMENT DUE TO WEAK LOW LEVEL WINDS WILL ALLOW FOR THREAT OF SOME PROLONGED HEAVY RAIN ON WED. HOWEVER...RAINFALL AMOUNTS ARE STILL UNCERTAIN. ADDITIONAL SHORTWAVE ENERGY LOOKS TO MOVE THROUGH THU...BUT LATEST MODEL RUNS KEEP THAT FARTHER SW...SO THE BEST POPS ARE FOR AREAS ALONG THE WI BORDER. A SFC HIGH MOVES THROUGH THU NIGHT INTO SAT NIGHT...BRINGING MOSTLY DRY WEATHER AND DECREASED CLOUDINESS. MODELS SHOW A SHORTWAVE MOVING THROUGH THE AREA SUN INTO MON...WITH DISAGREEMENT ON TIMING...WHICH WILL BRING RAIN TO THE AREA AS IT PASSES. THE SHORTWAVES LOOK TO AMPLIFY AN UPPER TROUGH OVER THE GREAT LAKES...WHICH MAY STICK AROUND INTO EARLY JULY. TEMPERATURES THROUGH THE NEXT 7 DAYS LOOK TO BE NEAR OR JUST BELOW NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 120 AM EDT TUE JUN 23 2015 AFTER A FEW HOURS OF LINGERING IFR/LIFR CIGS AT KCMX...CONDITIONS ARE EXPECTED TO BE VFR FOR THIS FORECAST PERIOD AS DRIER AIR WORKS IN BEHIND THE FRONT. WILL CONTINUE GUSTY INTO THIS MORNING BEHIND THE COLD FRONT AND SHOULD GET GUSTY AT CMX AGAIN LATE TUE AFTERNOON WITH A WEST WIND. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 418 PM EDT MON JUN 22 2015 A LOW PRES SYSTEM WIL MOVE EAST OF LAKE SUPERIOR TONIGHT. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 10 AM EDT THIS MORNING FOR LSZ251-266-267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
124 AM EDT TUE JUN 23 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 418 PM EDT MON JUN 22 2015 WV IMAGERY AND RAP ANALYSIS INDICATED A ZONAL PATTERN ACROSS THE NRN CONUS WITH A SHORTWAVE TROUGH FROM NW ONTARIO INTO NRN MN. THE RESIDUAL MCV GENERATED FROM THE LARGE MCS EARLIER TODAY WAS LOCATED NEAR NW LOWER MI. FORCING ASSOCIATED WITH THIS FEATURE AND 305K-310K ISENTROPIC ASCENT AHEAD OF THE SHRTWV SUPPORTED SOME SHRA OVER NRN UPPER MI. AT THE SFC...A COLD FRONT EXTENDED ACROSS ERN MN. SCT SHRA AND ISOLATED TS HAS ALSO DEVELOPED ALONG AND AHEAD OF THE FRONT WHERE HEIGHT FALLS AHEAD OF THE SHRTWV WERE MOVING IN. CLOUDS AND AREAS OF SHOWERS HAVE LIMITED HEATING/INSTABILITY WITH HIGHEST SB/MU CAPE VALUES ONLY UP TO AROUND 500 J/KG OVER THE WEST. EXPECT SCT SHRA/TSRA TO CONTINUE TO PUSH FROM NW WI THROUGH UPPER MI THIS EVENING. ALTHOUGH 0-6KM/0-1KM SHEAR VALUES OF 40-60KT/25-35KT WOULD BE FAVORABLE FOR SOME STRONG/SVR STORMS. EVEN WITH SOME ADDITIONAL CAPE RECOVERY...THE MARGINAL INSTABILITY WILL LIMIT THE SVR POTENTIAL. NEVERTHELESS...AN ISOLATED SVR STORM CANNOT BE RULED OUT. THE SCT SHRA/TSRA ARE EXPECTED TO MOVE OUT OF THE CNTRL AND EAST BTWN 03Z-06Z WITH DRY WEATHER THE REST OF THE NIGHT. GUSTY WINDS WILL DEVELOP BEHIND THE FRONT AND LOW PRES WITH THE PRES RISE MAX MOVING THROUGH THIS EVENING AND A TIGHT PRES GRADIENT LINGERING OVERNIGHT. TUE...HIGH PRES BUILDING FROM THE UPPER MS VALLEY INTO THE WRN GREAT LAKES WITH MUCH DRIER AIR WILL BRING MOSTLY SUNNY SKIES...BREEZY NW WINDS AND TEMPS NEAR SEASONAL AVERAGES FROM THE LOWER TO MID 70S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 325 PM EDT MON JUN 22 2015 SEVERAL SHORTWAVES WILL AFFECT THE UPPER GREAT LAKES REGION THROUGH THE REST OF THE WORK WEEK AND INTO THE WEEKEND...WHICH WILL SLOWLY DEVELOP AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND. ONCE THE UPPER TROUGH BECOMES ESTABLISHED IN THE GREAT LAKES REGION...ECMWF/GFS ENSEMBLES ARE CONSISTENT ON THE UPPER RIDGE DEVELOPING OVER THE PACIFIC NORTHWEST THIS WEEKEND TO SLOWLY SHIFT TO THE NORTHWEST AND REMAIN IN PLACE THROUGH THE FIRST WEEK OF JULY. THAT WILL LEAD TO A PERSISTENT PERIOD OF NORMAL TO BELOW NORMAL TEMPERATURES FOR THE GREAT LAKES REGION. SHIFTING BACK TO THIS WEEK...THE FIRST WAVE THAT WILL AFFECT THE CWA WILL BE MOVING ACROSS FAR NORTHERN ONTARIO ON TUESDAY NIGHT...WITH SOUTHWESTERN EDGE OF THAT WAVE BRUSHING THE NORTHEAST PART OF LAKE SUPERIOR. AT THE SURFACE...A WEAK TROUGH WILL BE MOVING ACROSS THE LAKE AND EXPECT THERE TO BE SOME SHOWERS ALONG IT IN NORTHWEST ONTARIO ON TUESDAY AFTERNOON. BUT WITH THE LOSS OF DIURNAL HEATING...LIMITED MOISTURE...AND THE BEST FORCING STAYING WELL TO THE NORTHEAST OF THE CWA...WILL ONLY SHOW SLIGHT CHANCE POPS MOVING SOUTHEAST ACROSS NORTHEAST LAKE SUPERIOR. DID BRUSH THE KEWEENAW WITH THOSE SLIGHT CHANCE POPS WITH A DECENT NUMBER OF MODELS SHOWING A FEW HUNDREDTHS OF QPF. OTHERWISE...EXPECT THE REST OF THE AREA TO BE PARTLY CLOUDY TO MOSTLY CLEAR ON TUESDAY NIGHT DUE TO THE RESIDUAL EFFECTS OF THE SLOWLY DEPARTING SURFACE RIDGE. THAT SURFACE RIDGE WILL STILL BE OVER THE GREAT LAKES REGION ON WEDNESDAY MORNING...AS THE PARENT HIGH MOVES INTO THE MID ATLANTIC STATES. BUT THE NEXT SHORTWAVE WILL BE QUICKLY APPROACHING THE AREA ON WEDNESDAY AFTERNOON. MODELS CONTINUE TO DEPICT LINGERING MOISTURE ASSOCIATED WITH THE TUESDAY NIGHT SURFACE TROUGH BEING OVER THE U.P. ON WEDNESDAY AFTERNOON AND THAT WILL COMBINE WITH THE ARRIVAL OF ADDITIONAL MOISTURE/FORCING AND LAKE BREEZE DEVELOPMENT TO LEAD TO SHOWERS AND A FEW THUNDERSTORMS OVER PORTIONS OF WEST/CENTRAL UPPER MICHIGAN. WILL CONTINUE TO SHOW THE BEST CHANCE FOR SHOWERS OVER THE LAND AREAS AND INLAND FROM THE GREAT LAKES...WITH THE BEST OPPORTUNITY ALONG THE EXPECTED LAKE BREEZE FROM CENTRAL MARQUETTE COUNTY WESTWARD TOWARDS ONTONAGON COUNTY. WILL CONTINUE TO KEEP THUNDER VALUES IN THE SLIGHT CHANCE CATEGORY WITH MLCAPE VALUES GENERALLY UNDER 500J/KG (BEST INSTABILITY WELL TO THE SOUTH AND TIED TO THE STRONG STORMS LIKELY MOVING THROUGH SOUTHERN MINNESOTA/WISCONSIN LATE WEDNESDAY AFTERNOON/NIGHT). 0-6KM BULK SHEAR VALUES LOOK FAIRLY STRONG (APPROACHING 50KTS)...BUT LOOKING AT THE SOUNDINGS...THAT IS ALL TIED TO THE STRONG JET BETWEEN 5-6KM. THUS...THINK THE EFFECTIVE SHEAR VALUES AROUND 20KTS ARE MORE REASONABLE AND BELIEVE THE POTENTIAL FOR STRONG STORMS IS LIMITED AT THIS POINT. THE ONLY CONCERN WOULD BE WITH THE SLOW STORM MOTIONS LEADING TO LOCALIZED HEAVY RAIN WHERE THE THUNDERSTORMS OCCUR. WHILE THAT FIRST WAVE WILL AFFECT THE AREA WEDNESDAY AFTERNOON/EVENING...THERE ARE SEVERAL WEAK WAVES TRAILING IT THAT WILL HAVE AN INFLUENCE ON THE WEATHER FOR THE U.P. THROUGH THURSDAY NIGHT. WILL SHOW CHANCE POPS AS THESE DISTURBANCES MOVE THROUGH AND CONTINUE SLIGHT CHANCE FOR THUNDER (ALTHOUGH THAT APPEARS TO BE FAIRLY OPTIMISTIC). THOSE WAVES WILL AMPLIFY AN UPPER TROUGH OVER THE GREAT LAKES REGION THIS WEEKEND AND LIKELY CONTINUE INTO EARLY JULY. THERE IS THE POTENTIAL FOR SOME DIURNAL SHOWERS THIS WEEKEND...ALTHOUGH THE SUBSIDENCE FROM A HIGH PRESSURE RIDGE MOVING THROUGH SHOULD LIMIT THE COVERAGE...BEFORE ANOTHER STRONGER WAVE DROPS SOUTHEAST ACROSS THE AREA ON MONDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 120 AM EDT TUE JUN 23 2015 AFTER A FEW HOURS OF LINGERING IFR/LIFR CIGS AT KCMX...CONDITIONS ARE EXPECTED TO BE VFR FOR THIS FORECAST PERIOD AS DRIER AIR WORKS IN BEHIND THE FRONT. WILL CONTINUE GUSTY INTO THIS MORNING BEHIND THE COLD FRONT AND SHOULD GET GUSTY AT CMX AGAIN LATE TUE AFTERNOON WITH A WEST WIND. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 418 PM EDT MON JUN 22 2015 A LOW PRES SYSTEM WIL MOVE EAST OF LAKE SUPERIOR TONIGHT. A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF THIS LOW WILL SUPPORT A PERIOD OF WNW 35 KNOT GALES LATE TONIGHT INTO TUE MORNING...STRONGEST OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN KEEP WINDS LIGHT AGAIN FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS WILL SUPPORT FOG ACROSS THE LAKE...THAT COULD BE LOCALLY DENSE INTO THIS EVENING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WARNING UNTIL 10 AM EDT THIS MORNING FOR LSZ251-266-267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...JLB
AREA FORECAST DISCUSSION
NWS BILLINGS MT
251 AM MDT TUE JUN 23 2015 .SHORT TERM...VALID FOR TDY AND WED... AS OF 0830Z AN AREA OF SHOWERS WITH A FEW LIGHTNING STRIKES EXISTS FROM NEAR HARDIN TO CARTER COUNTY. THIS A RESULT OF SOUTHEASTERLY LOW LEVEL JET AND MODEST ELEVATED INSTABILITY...AND LATEST PWAT ANALYSIS SHOWS VALUES NEAR AN INCH ACROSS OUR SOUTHEAST AS WE CONTINUE TO ADVECT MOISTURE UP THE HIGH PLAINS. FORCING FROM LOW LEVEL JET SHOULD DIMINISH EARLY THIS MORNING AND THIS IS CONSISTENT WITH RECENT HRRR RUNS...THUS EXPECT SHOWER ACTIVITY TO END OVER OUR SOUTHEAST A LITTLE AFTER SUNRISE. LOOKING TO THE WEST...THERE IS AN AREA OF PV MOVING FROM OR TO CENTRAL ID. THIS FEATURE SHOULD PROVIDE ASCENT FOR SHOWER AND THUNDERSTORM DEVELOPMENT LATER TODAY. IN FACT...WOULD NOT BE SURPRISED TO SEE SOME SHOWER ACTIVITY DEVELOP BEFORE NOON ACROSS OUR WEST PER TIMING OF THIS SHORTWAVE. WE ARE STILL EXPECTING A RISK OF SEVERE STORMS ACROSS OUR EAST THIS AFTERNOON AND EVENING PER CAPES OF 1200+ J/KG AND UP TO 50 KTS OF EFFECTIVE BULK SHEAR...AND ASCENT PROVIDED BY THE APPROACHING SHORTWAVE. HRRR/RAP SHOW A SURGE OF DRIER MIXED WEST WINDS PUSHING THRU MLS-4BQ. THIS WOULD SUGGEST DEEPER MOISTURE AND BEST SEVERE POTENTIAL WOULD BE CLOSE TO THE DAKOTAS BORDER... AND THIS MAY BE REASONABLE GIVEN SHORTWAVE WILL MOVE INTO SOUTHEAST MT AS EARLY AS 18Z. WILL NEED TO KEEP WATCH OF THIS. NEXT SHORTWAVE OVER NORTHERN WA WILL MOVE ACROSS THE HIGH LINE TONIGHT. WEAKER LOW LEVEL JET PLUS FORCING FROM THIS ENERGY WILL KEEP SHOWER AND TSTM CHANCES GOING THROUGH THE NIGHT ESPECIALLY FOR OUR EAST. COULD SEE TWO SEPARATE ROUNDS OF POTENTIAL SEVERE STORMS...ONE IN THE AFTERNOON AS ALREADY MENTIONED AND A SECOND IN THE EVENING PER THE SECONDARY SHORTWAVE. HAIL AND WIND ARE THE PRIMARY THREATS. YET ANOTHER SHORTWAVE IN THE PACIFIC FLOW ALOFT WILL MOVE INTO THE AREA WEDNESDAY. GFS/NAM SHOW EASTERLY LOW LEVEL FLOW PERSISTING ACROSS OUR EAST THROUGH WEDNESDAY...ALLOWING FOR HIGH PWATS AND DEEPER INSTABILITY AND IN FACT THE GFS SHOWS LIFTED INDICES TO -5C IN SOUTHEAST MT WEDNESDAY AFTERNOON. SHEAR WILL AGAIN BE SUFFICIENT FOR ORGANIZED STORMS AND FEEL THAT STRONG TO SEVERE ACTIVITY IS POSSIBLE TOMORROW AS WELL...AGAIN MAINLY IN OUR EAST. SMALL HAIL AND GUSTY WINDS STILL A POSSIBILITY FOR OUR WESTERN AREAS WITH CONVECTION TODAY AND WEDNESDAY. TEMPS WILL TURN WARMER TODAY WITH HIGHS GETTING INTO THE LOWER TO MID 80S. SHOULD BE SLIGHTLY COOLER WEDNESDAY BUT STILL A LITTLE ABOVE NORMAL. JKL .LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON... DEVELOPING RIDGE OVER IDAHO BEGINS TO INCREASE HEIGHTS OVER THE WESTERN ZONES ON THURSDAY BRINGING A MORE STABLE PATTERN. STILL HINTS OF SOUTHEASTERLY SURFACE FLOW ALONG THE MONTANA DAKOTA BORDER SO CANNOT COMPLETELY RULE OUT THUNDERSTORMS IN SOUTHEAST MONTANA. FOR FRIDAY AND BEYOND A DOMINANT RIDGE BEGINS TO BUILD OVER IDAHO AND WESTERN MONTANA AND LATEST RUNS SHIFT IT A BIT EASTWARD EARLY NEXT WEEK. THIS WILL SEVERELY LIMIT CONVECTIVE POTENTIAL AND BRING SUMMER LIKE TEMPERATURES...WITH READINGS 95 TO 100 POSSIBLE BY SUNDAY THROUGH TUESDAY. BORSUM && .AVIATION... ISOLATED SHOWERS AND THUNDERSTORMS SOUTH OF OF KMLS WILL MOVE INTO THE DAKOTAS SHORTLY AFTER DAYBREAK. ANOTHER ROUND OF ISOLATED SHOWERS AND THUNDERSTORMS WILL DEVELOP OVER THE MOUNTAINS THIS AFTERNOON SPREADING TO THE ADJACENT PLAINS BY LATE AFTERNOON. EXPECT ACTIVITY TO INCREASE IN THE EVENING AND SPREAD EASTWARD BECOMING MOST NUMEROUS OVER SOUTHEAST MONTANA. BORSUM && .PRELIMINARY POINT TEMP/POPS... TDY WED THU FRI SAT SUN MON ------------------------------------------------------- BIL 084 059/082 060/086 059/090 062/093 063/095 063/097 2/T 32/T 21/E 11/U 00/U 01/U 11/U LVM 084 049/084 053/086 052/091 054/095 056/096 056/097 3/T 32/T 21/B 11/U 00/U 11/U 11/U HDN 087 056/086 059/087 059/091 061/094 062/096 062/097 2/T 32/T 22/T 11/U 11/U 11/U 11/U MLS 085 059/083 060/084 059/087 061/090 061/092 063/093 2/T 44/T 32/T 32/T 10/U 01/U 11/U 4BQ 083 057/083 059/082 058/085 059/089 059/092 061/092 2/T 44/T 33/T 31/B 11/U 11/U 11/U BHK 080 057/080 058/081 057/082 058/086 058/088 060/087 3/T 54/T 33/T 32/T 21/U 11/U 11/U SHR 082 053/081 055/081 054/084 055/088 055/090 057/091 2/T 32/T 33/T 21/B 11/U 11/U 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
322 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH FRIDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 310 AM TUESDAY... MID LEVEL HEIGHTS WILL INCREASE A BIT MORE TODAY... WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 7 TO 8 METERS HIGHER TODAY. THUS... GIVEN SIMILAR CONDITIONS EXPECT WE SHOULD SEE HIGH TEMPS GENERALLY 2-3 DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS. THIS SHOULD RESULT IN HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES ACROSS THE AREA. THIS COMBINED WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA SHOULD RESULT IN SEVERAL HOURS OF HEAT INDEX VALUES THIS AFTERNOON OF AROUND 105 DEGREES. THUS... CURRENT HEAT ADVISORY LOOKS GOOD WITH NO CHANGES PLANNED AT THIS TIME. IN ADDITION TO THE HEAT... WE MAY SEE SOME AFTERNOON SHOWERS AND STORMS DEVELOP ALONG A REMNANT OUTFLOW AND MCV THAT IS CURRENTLY SINKING SOUTH AND EASTWARD INTO THE FA. THE LATEST RAP SHOWS THIS FEATURE SLOWLY SHIFTING SOUTH AND EASTWARD ACROSS CENTRAL NC THIS MORNING... WITH POSSIBLY A FEW WEAK SHOWERS DEVELOPING ALONG IT (NOTHING CURRENTLY ON RADAR). HOWEVER... AS THE FEATURE SHIFTS EASTWARD ACROSS THE AREA LATER TODAY... THINK WE MAY SEE SOME DEVELOPMENT ACROSS OUR SOUTHEASTERN/EASTERN COUNTIES... WHICH IS LOOSELY SHOWN BY SOME OF THE HIGH-RES GUIDANCES. GIVEN MODERATE INSTABILITY (IF WE INDEED GET SOME STORMS TO DEVELOP) WE COULD SEE A FEW STRONG TO PERHAPS SEVERE STORMS... MAINLY PULSE IN NATURE GIVEN CONTINUED WEAK DEEP LAYER SHEAR. THE NEXT FEATURE OF INTERESTED TODAY INTO THIS EVENING WILL BE THE APPROACH OF A COLD FRONT AND A CLUSTER OR LINE OF SHOWERS AND STORMS IN ADVANCE OF THE FRONT. SOME OF THE HI-RES (CAM`S) GUIDANCES SHOWS THIS LINE/DEVELOPMENT ALONG OUTFLOW MAKING IT INTO OUR AREA LATE TODAY INTO THIS EVENING. WHICH SEEMS POSSIBLE GIVEN THE EXPECTED NOCTURNAL RECOVERY OF DEWPOINTS AND RESULTANT CONTINUATION OF DECENT INSTABILITY. THUS... HAVE INCREASED POPS ACROSS THE NORTH/NORTHWESTERN HALF OF THE CWA FOR LATE TODAY INTO THE EVENING... WITH THE CONVECTION POSSIBLY LINGERING INTO THE EARLY MORNING HOURS OF WEDNESDAY. IF WE DO SEE SOME OF THIS ACTIVITY MAKING IT INTO OUR AREA EXPECT WE COULD SEE SOME ADDITIONAL STRONG TO SEVERE STORMS... WITH THE MAIN THREAT FROM DAMAGING WINDS. EXPECT THE ACTUAL COLD FRONT TO SINK SOUTHWARD AND INTO THE AREA NEAR 12Z WEDNESDAY. HOWEVER... EXPECT OVERNIGHT LOWS SHOULD REMAIN QUITE UNCOMFORTABLE... GENERALLY RANGING FROM THE LOWER TO UPPER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 320 AM TUESDAY... THE LATEST GFS AND ECMWF ARE IN GENERAL AGREEMENT ON SHOWING THE SURFACE FRONT SETTLE SOUTH AND EASTWARD INTO SOUTHEASTERN PORTIONS OF CENTRAL NC. THUS... EXPECT THE BEST CHANCE OF SHOWERS AND STORMS WEDNESDAY AFTERNOON AND EVENING WILL BE ACROSS THE COASTAL PLAIN AND SANDHILLS... GENERALLY SOUTH AND EAST OF RALEIGH. HIGH TEMPS ON WEDNESDAY ARE EXPECTED TO RANGE FROM THE LOWER 90S/NEAR 90 NORTH TO THE MID TO UPPER 90S SOUTH. OVERNIGHT LOWS WEDNESDAY NIGHT SHOULD RANGE FROM NEAR 70 NORTH TO THE MID 70S SOUTHEAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 135 AM TUESDAY... VFR CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE 24 HOUR TAF PERIOD. MID LEVEL HIGH PRESSURE WILL CONTINUE TO EXTEND INTO CENTRAL NC FROM THE WEST... HELPING TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS CENTRAL NC FOR THE MOST PART TODAY AND THIS EVENING. HOWEVER... A WEAK DISTURBANCE WILL SLOWLY TRACK ACROSS THE AREA THIS MORNING. THIS DISTURBANCE IS EXPECTED TO BE LOCATED NEAR THE SOUTHEASTERN/FAR EASTERN PORTION OF THE AREA BY THIS AFTERNOON... WHEN IT MAY HELP TO PRODUCE SOME SHOWERS AND STORMS. KFAY WOULD STAND THE BEST CHANCE OF SEEING ANY CONVECTIVE DEVELOPMENT FROM THIS FEATURE. HOWEVER... CONFIDENCE IS TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. OTHERWISE... DRY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE INTO EARLY THIS EVENING. A CONVECTIVE LINE ASSOCIATED WITH UPSTREAM CONVECTION ORIGINATING NEAR A SOUTH/SOUTHEASTWARD SINKING COLD FRONT (CURRENTLY LOCATED FROM THE PLAINS INTO THE GREAT LAKES) THIS AFTERNOON MAY SINK SOUTHWARD INTO OUR AREA THIS EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY (WELL AHEAD OF THE FRONT). NOT OVERLY CONFIDENT ON THE TIMING... BUT FEEL WE SHOULD SEE AT LEAST SOME SCATTERED SHOWERS AND STORMS ACROSS THE NORTHERN HALF OF CENTRAL NC BY THIS EVENING. THUS... HAVE ELECTED TO GO WITH A PROB30 GROUP FOR KGSO/KINT FOR NOW. ANY CONVECTION WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS... LIGHTNING... AND SUB-VFR CONDITIONS. OUTLOOK: THE ABOVE MENTION COLD FRONT IS NOW EXPECTED TO SETTLE INTO CENTRAL NC ON WEDNESDAY... POSSIBLY STALLING ACROSS SOUTHERN AND EASTERN PORTIONS OF THE AREA (THIS IS WHERE THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE ON WEDNESDAY). AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...77 SHORT TERM...77 LONG TERM...WSS AVIATION...77/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
311 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH FRIDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 310 AM TUESDAY... MID LEVEL HEIGHTS WILL INCREASE A BIT MORE TODAY... WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 7 TO 8 METERS HIGHER TODAY. THUS... GIVEN SIMILAR CONDITIONS EXPECT WE SHOULD SEE HIGH TEMPS GENERALLY 2-3 DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS. THIS SHOULD RESULT IN HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES ACROSS THE AREA. THIS COMBINED WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA SHOULD RESULT IN SEVERAL HOURS OF HEAT INDEX VALUES THIS AFTERNOON OF AROUND 105 DEGREES. THUS... CURRENT HEAT ADVISORY LOOKS GOOD WITH NO CHANGES PLANNED AT THIS TIME. IN ADDITION TO THE HEAT... WE MAY SEE SOME AFTERNOON SHOWERS AND STORMS DEVELOP ALONG A REMNANT OUTFLOW AND MCV THAT IS CURRENTLY SINKING SOUTH AND EASTWARD INTO THE FA. THE LATEST RAP SHOWS THIS FEATURE SLOWLY SHIFTING SOUTH AND EASTWARD ACROSS CENTRAL NC THIS MORNING... WITH POSSIBLY A FEW WEAK SHOWERS DEVELOPING ALONG IT (NOTHING CURRENTLY ON RADAR). HOWEVER... AS THE FEATURE SHIFTS EASTWARD ACROSS THE AREA LATER TODAY... THINK WE MAY SEE SOME DEVELOPMENT ACROSS OUR SOUTHEASTERN/EASTERN COUNTIES... WHICH IS LOOSELY SHOWN BY SOME OF THE HIGH-RES GUIDANCES. GIVEN MODERATE INSTABILITY (IF WE INDEED GET SOME STORMS TO DEVELOP) WE COULD SEE A FEW STRONG TO PERHAPS SEVERE STORMS... MAINLY PULSE IN NATURE GIVEN CONTINUED WEAK DEEP LAYER SHEAR. THE NEXT FEATURE OF INTERESTED TODAY INTO THIS EVENING WILL BE THE APPROACH OF A COLD FRONT AND A CLUSTER OR LINE OF SHOWERS AND STORMS IN ADVANCE OF THE FRONT. SOME OF THE HI-RES (CAM`S) GUIDANCES SHOWS THIS LINE/DEVELOPMENT ALONG OUTFLOW MAKING IT INTO OUR AREA LATE TODAY INTO THIS EVENING. WHICH SEEMS POSSIBLE GIVEN THE EXPECTED NOCTURNAL RECOVERY OF DEWPOINTS AND RESULTANT CONTINUATION OF DECENT INSTABILITY. THUS... HAVE INCREASED POPS ACROSS THE NORTH/NORTHWESTERN HALF OF THE CWA FOR LATE TODAY INTO THE EVENING... WITH THE CONVECTION POSSIBLY LINGERING INTO THE EARLY MORNING HOURS OF WEDNESDAY. IF WE DO SEE SOME OF THIS ACTIVITY MAKING IT INTO OUR AREA EXPECT WE COULD SEE SOME ADDITIONAL STRONG TO SEVERE STORMS... WITH THE MAIN THREAT FROM DAMAGING WINDS. EXPECT THE ACTUAL COLD FRONT TO SINK SOUTHWARD AND INTO THE AREA NEAR 12Z WEDNESDAY. HOWEVER... EXPECT OVERNIGHT LOWS SHOULD REMAIN QUITE UNCOMFORTABLE... GENERALLY RANGING FROM THE LOWER TO UPPER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 310 AM TUESDAY... COMING SHORTLY && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 135 AM TUESDAY... VFR CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE 24 HOUR TAF PERIOD. MID LEVEL HIGH PRESSURE WILL CONTINUE TO EXTEND INTO CENTRAL NC FROM THE WEST... HELPING TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS CENTRAL NC FOR THE MOST PART TODAY AND THIS EVENING. HOWEVER... A WEAK DISTURBANCE WILL SLOWLY TRACK ACROSS THE AREA THIS MORNING. THIS DISTURBANCE IS EXPECTED TO BE LOCATED NEAR THE SOUTHEASTERN/FAR EASTERN PORTION OF THE AREA BY THIS AFTERNOON... WHEN IT MAY HELP TO PRODUCE SOME SHOWERS AND STORMS. KFAY WOULD STAND THE BEST CHANCE OF SEEING ANY CONVECTIVE DEVELOPMENT FROM THIS FEATURE. HOWEVER... CONFIDENCE IS TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. OTHERWISE... DRY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE INTO EARLY THIS EVENING. A CONVECTIVE LINE ASSOCIATED WITH UPSTREAM CONVECTION ORIGINATING NEAR A SOUTH/SOUTHEASTWARD SINKING COLD FRONT (CURRENTLY LOCATED FROM THE PLAINS INTO THE GREAT LAKES) THIS AFTERNOON MAY SINK SOUTHWARD INTO OUR AREA THIS EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY (WELL AHEAD OF THE FRONT). NOT OVERLY CONFIDENT ON THE TIMING... BUT FEEL WE SHOULD SEE AT LEAST SOME SCATTERED SHOWERS AND STORMS ACROSS THE NORTHERN HALF OF CENTRAL NC BY THIS EVENING. THUS... HAVE ELECTED TO GO WITH A PROB30 GROUP FOR KGSO/KINT FOR NOW. ANY CONVECTION WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS... LIGHTNING... AND SUB-VFR CONDITIONS. OUTLOOK: THE ABOVE MENTION COLD FRONT IS NOW EXPECTED TO SETTLE INTO CENTRAL NC ON WEDNESDAY... POSSIBLY STALLING ACROSS SOUTHERN AND EASTERN PORTIONS OF THE AREA (THIS IS WHERE THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE ON WEDNESDAY). AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...77 SHORT TERM...77 LONG TERM...WSS AVIATION...77/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH FRIDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 PM MONDAY... CENTRAL NC REMAINS WITHIN A LOW-LEVEL MOISTURE MINIMUM THIS AFTERNOON...AS INDICATED BY 925-850 MB DEWPOINTS ~14C (PER SPC MESOANALYSIS)...AND AS ONE MIGHT INFER GIVEN WEAK/MODEST MID-LEVEL LAPSE RATES (NO SIGNIFICANT CAP) AND A LACK OF DIURNAL CU. AS A RESULT...INSTABILITY IS WEAKER AND CONVECTIVE INHIBITION IS GREATER THAN IN SURROUNDING AREAS...AND IT IS UNLIKELY THAT CONVECTION WILL DEVELOP WITHIN CENTRAL NC THE REMAINDER OF THE AFTERNOON. AN MCV WAS NOTED UPSTREAM OVER SOUTHEAST KY AT 21Z THIS AFTERNOON. THE LATEST RAP GUIDANCE INDICATES THIS FEATURE WILL TRACK SLOWLY ESE INTO SOUTHWEST VA BY ~00Z...SOUTHEASTWARD TO BOONE NC BY ~03Z... SSE/SOUTHWARD TO MORGANTON BY ~06Z AND CHARLOTTE BY ~09Z. IT IS POSSIBLE THAT DPVA ASSOCIATED WITH THIS FEATURE COULD PROVIDE SUFFICIENT FORCING TO AID CONVECTIVE DEVELOPMENT IN NORTHWEST NC AFTER 00Z...WITH PROPAGATION INTO THE TRIAD/NW PIEDMONT POSSIBLE BY ~03Z. IT SHOULD BE NOTED THAT NONE OF THE 12Z CAMS SUPPORT SUCH DEVELOPMENT...PROBABLY DUE TO UNFAVORABLE DIURNAL TIMING AND A DRIER/LESS SUPPORTIVE CONVECTIVE ENVIRONMENT...ASSUMING NO SIGNIFICANT LOW-LEVEL MOISTURE RECOVERY AFTER SUNSET. SHOULD CONVECTION DEVELOP OR PROPAGATE INTO THE TRIAD...DCAPE VALUES RANGING FROM 1000-1200 J/KG SUGGESTS ROBUST DOWNDRAFTS/COLD POOLS AND AN ATTENDANT POTENTIAL FOR DAMAGING WINDS...THOUGH DEEP LAYER SHEAR WILL BE MARGINALLY SUPPORTIVE OF MULTICELLULAR ORGANIZATION (AT BEST). -VINCENT && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 240 PM MONDAY... THE SUB-TROPICAL RIDGE WILL STRENGTHEN TO 325-326 DM OVER THE MID- SOUTH ON TUE...WITH AN ASSOCIATED UPTICK IN DOWNSTREAM LOW LEVEL THICKNESS VALUES AOA 1440 METERS OVER CENTRAL NC. HIGH TEMPERATURES ARE CONSEQUENTLY EXPECTED TO REACH THE UPPER 90S TO AROUND 100 DEGREES...LIKELY THE HOTTEST DAY OF THE WEEK. MODEL GUIDANCE SUGGESTS SFC DEWPOINTS WILL NOT MIX OUT AS MUCH AS PREVIOUS DAYS...AT LEAST NOT IN THE COASTAL PLAIN AND EASTERN SANDHILLS... WHERE AOA 70 DEGREES IS EXPECTED. AS SUCH...HEAT INDEX VALUES ARE FORECAST AROUND 105 DEGREES OR SO DURING THE AFTERNOON; AND ANOTHER HEAT ADVISORY HAS BEEN ISSUED FOR THE AREAS GENERALLY ALONG AND EAST OF INTERSTATE 95. SINCE THE PRIMARY FRONT...LIKELY A CONVECTIVELY-MODULATED ONE WILL REMAIN NORTH OF THE VA/NC BORDER THROUGH AT LEAST 12Z WED...FORCING AT THIS LATITUDE WILL NEED TO COME FROM OUTFLOW AND/OR AN MCV FROM UPSTREAM CONVECTION...NEITHER OF WHICH CAN BE FORECAST WITH MUCH CONFIDENCE AT THIS TIME RANGE. POP WILL CONSEQUENTLY BE KEPT IN THE SLIGHT TO LOW CHANCE RANGE...WITH THE RELATIVE BEST CHANCE ACROSS THE NORTHERN PIEDMONT LATE IN THE AFTERNOON AND EARLY EVENING GIVEN THE ORIENTATION OF THE RIDGE TO THE SOUTH AND ASSOCIATED TRACK OF MCS/S ACROSS THE TN VALLEY-CENTRAL APPALACHIANS. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /00Z TUESDAY THROUGH SATURDAY/... AS OF 748 PM MONDAY... A FEW VERY ISOLATED SHOWERS/STORMS HAVE DEVELOPED IN ASSOCIATION WITH THE SEA BREEZE IN THE SOUTHERN COUNTIES... AND IN THE VICINITY OF KFAY. THIS ACTIVITY WILL BE SHORT LIVED. OTHERWISE VFR CONDITIONS ARE LIKELY THROUGH THE NEXT 24 HOURS AS HIGH PRESSURE REMAINS ACROSS THE AREA. WINDS WILL BECOME SOUTHWESTERLY BY TOMORROW AFTERNOON. SHOWERS AND STORMS WILL HAVE A RELATIVELY LOW PROBABILITY OF OCCURRENCE (~20 PERCENT) UNTIL A CONVECTIVE OUTFLOW-MODULATED FRONT SETTLES SOUTH INTO VA-NC ON WED AND SUPPORTS A BETTER CHANCE (30-50 PERCENT) AT THAT TIME. AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...VINCENT SHORT TERM...26 LONG TERM...WSS AVIATION...30/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
137 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH THURSDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 PM MONDAY... CENTRAL NC REMAINS WITHIN A LOW-LEVEL MOISTURE MINIMUM THIS AFTERNOON...AS INDICATED BY 925-850 MB DEWPOINTS ~14C (PER SPC MESOANALYSIS)...AND AS ONE MIGHT INFER GIVEN WEAK/MODEST MID-LEVEL LAPSE RATES (NO SIGNIFICANT CAP) AND A LACK OF DIURNAL CU. AS A RESULT...INSTABILITY IS WEAKER AND CONVECTIVE INHIBITION IS GREATER THAN IN SURROUNDING AREAS...AND IT IS UNLIKELY THAT CONVECTION WILL DEVELOP WITHIN CENTRAL NC THE REMAINDER OF THE AFTERNOON. AN MCV WAS NOTED UPSTREAM OVER SOUTHEAST KY AT 21Z THIS AFTERNOON. THE LATEST RAP GUIDANCE INDICATES THIS FEATURE WILL TRACK SLOWLY ESE INTO SOUTHWEST VA BY ~00Z...SOUTHEASTWARD TO BOONE NC BY ~03Z... SSE/SOUTHWARD TO MORGANTON BY ~06Z AND CHARLOTTE BY ~09Z. IT IS POSSIBLE THAT DPVA ASSOCIATED WITH THIS FEATURE COULD PROVIDE SUFFICIENT FORCING TO AID CONVECTIVE DEVELOPMENT IN NORTHWEST NC AFTER 00Z...WITH PROPAGATION INTO THE TRIAD/NW PIEDMONT POSSIBLE BY ~03Z. IT SHOULD BE NOTED THAT NONE OF THE 12Z CAMS SUPPORT SUCH DEVELOPMENT...PROBABLY DUE TO UNFAVORABLE DIURNAL TIMING AND A DRIER/LESS SUPPORTIVE CONVECTIVE ENVIRONMENT...ASSUMING NO SIGNIFICANT LOW-LEVEL MOISTURE RECOVERY AFTER SUNSET. SHOULD CONVECTION DEVELOP OR PROPAGATE INTO THE TRIAD...DCAPE VALUES RANGING FROM 1000-1200 J/KG SUGGESTS ROBUST DOWNDRAFTS/COLD POOLS AND AN ATTENDANT POTENTIAL FOR DAMAGING WINDS...THOUGH DEEP LAYER SHEAR WILL BE MARGINALLY SUPPORTIVE OF MULTICELLULAR ORGANIZATION (AT BEST). -VINCENT && .SHORT TERM /TUESDAY AND TUESDAY NIGHT/... AS OF 240 PM MONDAY... THE SUB-TROPICAL RIDGE WILL STRENGTHEN TO 325-326 DM OVER THE MID- SOUTH ON TUE...WITH AN ASSOCIATED UPTICK IN DOWNSTREAM LOW LEVEL THICKNESS VALUES AOA 1440 METERS OVER CENTRAL NC. HIGH TEMPERATURES ARE CONSEQUENTLY EXPECTED TO REACH THE UPPER 90S TO AROUND 100 DEGREES...LIKELY THE HOTTEST DAY OF THE WEEK. MODEL GUIDANCE SUGGESTS SFC DEWPOINTS WILL NOT MIX OUT AS MUCH AS PREVIOUS DAYS...AT LEAST NOT IN THE COASTAL PLAIN AND EASTERN SANDHILLS... WHERE AOA 70 DEGREES IS EXPECTED. AS SUCH...HEAT INDEX VALUES ARE FORECAST AROUND 105 DEGREES OR SO DURING THE AFTERNOON; AND ANOTHER HEAT ADVISORY HAS BEEN ISSUED FOR THE AREAS GENERALLY ALONG AND EAST OF INTERSTATE 95. SINCE THE PRIMARY FRONT...LIKELY A CONVECTIVELY-MODULATED ONE WILL REMAIN NORTH OF THE VA/NC BORDER THROUGH AT LEAST 12Z WED...FORCING AT THIS LATITUDE WILL NEED TO COME FROM OUTFLOW AND/OR AN MCV FROM UPSTREAM CONVECTION...NEITHER OF WHICH CAN BE FORECAST WITH MUCH CONFIDENCE AT THIS TIME RANGE. POP WILL CONSEQUENTLY BE KEPT IN THE SLIGHT TO LOW CHANCE RANGE...WITH THE RELATIVE BEST CHANCE ACROSS THE NORTHERN PIEDMONT LATE IN THE AFTERNOON AND EARLY EVENING GIVEN THE ORIENTATION OF THE RIDGE TO THE SOUTH AND ASSOCIATED TRACK OF MCS/S ACROSS THE TN VALLEY-CENTRAL APPALACHIANS. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 315 PM MONDAY... WED/WED NIGHT: THE EXTENDED PERIOD WILL START WITH THE UPPER LEVEL HIGH CENTERED OVER THE MID-MS RIVER VALLEY AND THE UPPER LEVEL LOW OVER NE CANADA. CENTRAL NC WILL BE SANDWICHED IN BETWEEN THE TWO...WITH GENERALLY NW FLOW ALOFT. THE RIDGE WILL WEAKEN THROUGHOUT THE DAY...WITH INCREASING CHANCES FOR CONVECTION AS THE TROUGH PUSHES SOUTHWARD. MEANWHILE...A SURFACE BACKDOOR COLD FRONT WILL SLIDE SOUTH... STALLING OUT AROUND THE NC/VA BORDER BY LATE WED AFT/EVE. HIGHS WILL GENERALLY BE IN THE MID TO UPPER 90S NORTH TO SOUTH. OVERNIGHT LOWS IN THE LOW TO MID 70S. THROUGH THE WEEKEND: FOR THE REMAINDER OF THE EXTENDED...THE SURFACE FRONT WILL LIFT NORTHWARD AND PUSH SOUTHWARD AS A LOW SLOWLY DEVELOPS OVER THE UPPER MIDWEST. THE NEARLY ZONAL FLOW ALOFT WITH A S/W OR TWO WILL GRADUALLY BECOME A MORE AMPLIFIED TROUGH LATE IN THE WEEK... PROGRESSING INTO THE EASTERN U.S. LATE IN THE WEEK AND OVER THE WEEKEND. CONFIDENCE REGARDING CONVECTIVE CHANCES/TIMING/COVERAGE IS NOT TERRIBLY HIGH AT THIS TIME...HOWEVER THERE IS AT LEAST A CHANCE FOR SHOWERS/STORMS NEARLY EVERY DAY. HIGHS WILL GENERALLY BE IN THE MID 90S THROUGH FRIDAY...WITH THE INDICATION IN THE MODELS OF A COOLING TREND OVER THE WEEKEND. HIGHS SAT IN THE UPPER 80S TO LOW 90S. LOWS WILL FOLLOW A SIMILAR TREND... DECREASING INTO THE UPPER 60S TO MID 70S BY FRI NIGHT. SATURDAY NIGHT ONWARD: THE MODELS ARE CONSISTENTLY INDICATING COOL SURFACE HIGH PRESSURE RIDGING INTO CENTRAL NC FROM THE NORTHEAST BY SUNDAY...WHICH WOULD RESULT IN COOLER TEMPERATURES ACROSS THE REGION. ALTHOUGH NOT TERRIBLY CONFIDENT...HIGHS SUNDAY COULD BE IN THE MID TO UPPER 80S...WITH LOWS IN THE MID 60S TO LOW 70S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 135 AM TUESDAY... VFR CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE 24 HOUR TAF PERIOD. MID LEVEL HIGH PRESSURE WILL CONTINUE TO EXTEND INTO CENTRAL NC FROM THE WEST... HELPING TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS CENTRAL NC FOR THE MOST PART TODAY AND THIS EVENING. HOWEVER... A WEAK DISTURBANCE WILL SLOWLY TRACK ACROSS THE AREA THIS MORNING. THIS DISTURBANCE IS EXPECTED TO BE LOCATED NEAR THE SOUTHEASTERN/FAR EASTERN PORTION OF THE AREA BY THIS AFTERNOON... WHEN IT MAY HELP TO PRODUCE SOME SHOWERS AND STORMS. KFAY WOULD STAND THE BEST CHANCE OF SEEING ANY CONVECTIVE DEVELOPMENT FROM THIS FEATURE. HOWEVER... CONFIDENCE IS TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. OTHERWISE... DRY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE INTO EARLY THIS EVENING. A CONVECTIVE LINE ASSOCIATED WITH UPSTREAM CONVECTION ORIGINATING NEAR A SOUTH/SOUTHEASTWARD SINKING COLD FRONT (CURRENTLY LOCATED FROM THE PLAINS INTO THE GREAT LAKES) THIS AFTERNOON MAY SINK SOUTHWARD INTO OUR AREA THIS EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY (WELL AHEAD OF THE FRONT). NOT OVERLY CONFIDENT ON THE TIMING... BUT FEEL WE SHOULD SEE AT LEAST SOME SCATTERED SHOWERS AND STORMS ACROSS THE NORTHERN HALF OF CENTRAL NC BY THIS EVENING. THUS... HAVE ELECTED TO GO WITH A PROB30 GROUP FOR KGSO/KINT FOR NOW. ANY CONVECTION WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS... LIGHTNING... AND SUB-VFR CONDITIONS. OUTLOOK: THE ABOVE MENTION COLD FRONT IS NOW EXPECTED TO SETTLE INTO CENTRAL NC ON WEDNESDAY... POSSIBLY STALLING ACROSS SOUTHERN AND EASTERN PORTIONS OF THE AREA (THIS IS WHERE THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE ON WEDNESDAY). AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND. SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/22 100 1981 06/23 100 1986 06/24 99 2010 GSO RECORDS 06/22 100 1914 06/23 102 1914 06/24 103 1914 FAY RECORDS 06/22 101 1990 06/23 102 1981 06/24 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT TUESDAY FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...VINCENT SHORT TERM...26 LONG TERM...RAH AVIATION...77/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1229 AM CDT TUE JUN 23 2015 .UPDATE... ISSUED AT 1225 AM CDT TUE JUN 23 2015 NO MAJOR CHANGES MADE FOR THIS UPDATE. IN SPACE WEATHER NEWS... A STRONG GEOMAGNETIC STORM CONTINUES TO PRODUCE WIDESPREAD AURORA BOREALLIS ACTIVITY ACROSS NORTH DAKOTA. UPDATE ISSUED AT 940 PM CDT MON JUN 22 2015 NO CHANGES REQUIRED WITH THIS UPDATE OTHER THAN TO BLEND TO OBSERVED TRENDS THROUGH 02 UTC. THE 00-01 UTC HRRR ITERATIONS AND 00 UTC NAM ARE IN AGREEMENT ON ELEVATED CONVECTION DEVELOPING LATE TONIGHT TO REMAIN ACROSS NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA WITH INCREASING MOISTURE TRANSPORT IN ASSOCIATION WITH A MODEST LOW LEVEL JET. UPDATE ISSUED AT 627 PM CDT MON JUN 22 2015 NO SIGNIFICANT CHANGES WITH THIS FORECAST UPDATE WITH WEAK HIGH PRESSURE IN PLACE...AS A MOSTLY CLEAR OVERNIGHT IS EXPECTED FOR THE POTENTIAL STRONG NORTHERN LIGHTS SHOW. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 208 PM CDT MON JUN 22 2015 LATEST VISIBLE SATELLITE SHOWS A CUMULUS FIELD COVERING MOST OF WESTERN AND CENTRAL NORTH DAKOTA. VERTICAL EXTENT APPEARS LIMITED WITH BASES AROUND 4000FT EXTENDING UP TO AROUND 6000FT. SUBSIDENCE AND DRY AIR ALOFT WILL INHIBIT VERTICAL GROWTH AND HENCE LIMIT CHANCES FOR PRECIPITATION MINIMAL TO NIL. MAINTAINED A SLIGHT CHC POPS OVER THE HIGHER TERRAIN COVERING THE TURTLE MOUNTAINS SOUTH TO THE JAMES RIVER VALLEY. CLOUDS WILL WANE NEAR SUNSET WITH A MAINLY CLEAR SKY OVERNIGHT. LATEST WATER VAPOR IMAGERY SHOWS OUR NEXT SHORTWAVE TROUGH APPROACHING VANCOUVER ISLAND. THIS IS FORECAST TO MOVE EAST TUESDAY...REACHING NORTHWEST MONTANA/SOUTHERN ALBERTA BY 00Z WEDNESDAY. INSTABILITY WILL INCREASE TUESDAY AFTERNOON...MOSTLY ACROSS SOUTHWEST AS SOUTHERLY WINDS ADVECT HIGHER DEWPOINTS/MOISTURE. BY LATE AFTERNOON...CAPE INCREASES TO 1200 J/KG WITH 0-6KM SHEAR AT 50KT TO 60KT. HAVE CONTINUED WITH A SLIGHT CHANCE OF THUNDERSTORMS WEST AND NORTH TUESDAY AFTERNOON...WITH DRY CONDITIONS ELSEWHERE. AFTERNOON HIGHS WILL BE WARMER...BETWEEN 77F AND 82F. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 208 PM CDT MON JUN 22 2015 THE CURRENT SUITE OF ENSEMBLE AND DETERMINISTIC MODELS PROVIDE GENERAL AGREEMENT ON AN UPPER LEVEL SHORTWAVE TROUGH MOVING ACROSS THE STATE LATE TUESDAY THROUGH WEDNESDAY. THE WEATHER PREDICTION CENTER DAYS 1-3 HAS ROUGHLY HALF AN INCH OF QPF ACROSS THE STATE...AS A RESULT OF ASSOCIATED SHOWERS AND THUNDERSTORMS. THEREAFTER...QUASI ZONAL FLOW ALOFT IS EXPECTED TO TRANSITION INTO NORTHWEST FLOW BY THURSDAY...AS AN UPPER LEVEL RIDGE BUILDS OVER THE CONUS SOUTHWEST. NORTHWEST FLOW IS EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE LONG TERM WITH SEVERAL EMBEDDED MID-LEVEL SHORTWAVES PROJECTED ACROSS THE AREA. FREQUENT CHANCES FOR ISOLATED/SCATTERED THUNDERSTORMS ARE EXPECTED...THOUGH PREDICTABILITY IS LOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1225 AM CDT TUE JUN 23 2015 VFR CONDITIONS AT ALL TAF SITES THROUGH THE TAF PERIOD. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AJ SHORT TERM...KS LONG TERM...AC AVIATION...AJ
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1127 PM CDT MON JUN 22 2015 .UPDATE... UPDATED TO ADD 06Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 715 PM CDT MON JUN 22 2015/ UPDATE...EVENING UPDATE. UPDATED TO REMOVE TH HEAT ADVISORY THIS AFTERNOON. MORE HEAT IS IN STORE FOR TOMORROW...ALTHOUGH CLOUDS AND HAZE HAS PREVENTED TEMPERATURES FROM CLIMBING AS HIGH AS THEY COULD HAVE. FORECAST LOOKS TO BE IN GOOD SHAPE. NO MORE RAIN IS EXPECTED TONIGHT WITH LOWS IN THE MIDDLE 70S. PREV DISCUSSION... /ISSUED 605 PM CDT MON JUN 22 2015/ UPDATE... UPDATED TO ADD 00Z AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 318 PM CDT MON JUN 22 2015/ DISCUSSION... CURRENTLY...A STRONG UPPER RIDGE CONTINUES TO BUILD EAST FROM THE SOUTHERN PLAINS. MOISTURE HAS POOLED ACROSS THE MIDSOUTH TODAY WITH PRECIP H20 VALUES APPROACHING 2 INCHES AND SURFACE DEWPOINTS IN THE MID 70S. THIS DEEPER MOISTURE COMBINED WITH A WEAK DISTURBANCE MOVING AROUND THE WESTERN EDGE OF THE UPPER RIDGE HAS TOUCHED OFF AN AREA OF THUNDERSTORMS ACROSS PARTS OF WEST TENNESSEE AND NORTHEAST MISSISSIPPI. THE HRRR DID AN EXCELLENT JOB WITH COMPLEX. TO THE WEST OF THE THUNDERSTORMS THE HEAT AND HUMIDITY IS BUILDING. HEAT INDEX VALUES HAVE REACHED 105 AT JONESBORO AND WEST MEMPHIS. TONIGHT...THUNDERSTORMS ACROSS EASTERN SECTIONS WILL PUSH EAST AND DISSIPATE BY EARLY THIS EVENING LEAVING BEHIND MOSTLY CLEAR SKIES. TEMPS WILL BE MILD WITH LOWS IN THE 70S. TUESDAY THROUGH THURSDAY...THE STRONG UPPER RIDGE WILL CONTINUE TO BUILD OVER THE AREA ON TUESDAY. BY WEDNESDAY IT WILL BE CENTERED DIRECTLY OVER THE AREA THEN START TO GRADUALLY WEAKEN ON THURSDAY. THIS WILL BE A HOT AND HUMID PERIOD. THOUGH ISOLATED SHOWERS AND THUNDERSTORMS CANNOT BE RULED OUT TUESDAY AND WEDNESDAY COVERAGE SHOULD BE MINIMAL. HIGHS ON TUESDAY WILL PUSH INTO THE MID 90S WHICH WHEN COMBINED WITH HIGH HUMIDITY WILL CREATE HEAT INDEX VALUES GREATER THAN 105 ACROSS MUCH OF THE MS DELTA INCLUDING THE MEMPHIS METRO AREA. A HEAT ADVISORY CONTINUES THROUGH 7 PM TUESDAY FOR THE AFOREMENTIONED AREA. BY WEDNESDAY TEMPS MAY HIT THE UPPER 90S IN A FEW SPOTS AND THE HEAT ADVISORY WILL PROBABLY NEED TO BE EXPANDED. BY THURSDAY THE UPPER RIDGE WEAKENS SLIGHTLY AND SOME DEEPER MOISTURE MOVES IN FROM THE SOUTH WHICH WILL RESULT IN BETTER SHOWER/THUNDERSTORM COVERAGE...ESPECIALLY ACROSS NORTH MISSISSIPPI. IT WILL STILL BE QUITE HOT WITH HIGHS IN THE MID 90S IN SOME PLACES SO HEAT ADVISORIES MAY BE NEEDED ON THURSDAY AS WELL. FRIDAY INTO THE WEEKEND...MEDIUM RANGE MODELS ARE IN GOOD AGREEMENT WITH BREAKING DOWN THE UPPER RIDGE AS A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S. A COLD FRONT WILL PUSH THROUGH THE MIDSOUTH FRIDAY AND SATURDAY WITH NUMEROUS SHOWERS AND THUNDERSTORMS. RAIN CHANCES WILL DIMINISH LATER SATURDAY AND SUNDAY. MUCH COOLER AIR WILL PUSH INTO THE AREA FOR THE WEEKEND WITH HIGHS IN THE 80S AND LOWS IN THE 60S. SJM && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS EXPECTED TO PREVAIL THROUGH THE PERIOD. WINDS WILL DIMINISH TO 5 KTS OR LESS TONIGHT AND INCREASE TO 8-11 KTS AFTER 23/15Z THEN DECREASE TO 6 KTS OR LESS AFTER 24/01Z. CJC && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR CRAIGHEAD- CRITTENDEN-CROSS-LEE AR-MISSISSIPPI-PHILLIPS-POINSETT-ST. FRANCIS. MO...NONE. MS...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR COAHOMA-DESOTO- PANOLA-QUITMAN-TALLAHATCHIE-TATE-TUNICA. TN...HEAT ADVISORY FROM 11 AM TO 7 PM CDT TUESDAY FOR SHELBY-TIPTON. && $$
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1230 AM CDT TUE JUN 23 2015 .AVIATION... OTHER THAN A FEW ISOLATED SHOWERS LEFT ACROSS THE COASTAL PLAINS AND RIO GRANDE PRECIPITATION HAS ENDED ACROSS SOUTH CENTRAL TEXAS. SKIES ARE MOSTLY VFR WITH MVFR CIGS JUST MOVING INTO DRT. HAVE PUSHED BACK THE ONSET OF MVFR CIGS AT THE I-35 TERMINALS TO 07Z. CEILINGS WILL CONTINUE TO DROP TO IFR BY 09Z FOR ALL TERMINALS. IMPROVEMENT TO MVFR IS EXPECTED AROUND 15Z TUESDAY MORNING ACROSS SOUTH CENTRAL TEXAS WITH VFR CONDITIONS RETURNING BY 18Z. ISOLATED SHOWERS AND THUNDERSTORMS ARE EXPECTED TOMORROW AFTERNOON DUE TO THE MOIST CONDITIONS STILL IN PLACE AND DAY TIME HEATING. HAVE COVERED THIS WITH VCSH FOR TOMORROW AFTERNOON FOR THE I-35 TERMINALS. CHANCES REMAIN SLIGHTLY BETTER AT DRT ALONG THE RIO GRANDE PLAINS SO VCSH IS IN THE TAF FOR THE MAJORITY OF THE TAF PERIOD. WINDS WILL BE OUT OF THE SOUTHEAST BETWEEN 5 AND 10 KNOTS THROUGH THE PERIOD. && .PREV DISCUSSION... /ISSUED 652 PM CDT MON JUN 22 2015/ AVIATION... ALONG THE RIO GRANDE...BAND OF SHRA/ISOLD TSRA WILL PERSIST FOR THE NEXT FEW HOURS WITH ADDITIONAL SHRA/TSRA POSSIBLE OVERNIGHT INTO TUESDAY AS UPPER LEVEL TROUGH LINGERS OVER MEXICO AND HAVE VCSH FOR KDRT THROUGH THE FORECAST. ELSEWHERE...ISOLD SHRA/TSRA ARE POSSIBLE THIS EVENING THROUGH TUESDAY WITH VCSH MENTIONED AT KAUS/KSAT/KSSF ONLY FOR TUESDAY AFTERNOON DUE BEST FORCING WITH DAYTIME HEATING. VFR SKIES EARLY THIS EVENING WILL LOWER TO MVFR CIGS AS STRATUS DEVELOPS. CIGS WILL LOWER TO IFR/LIFR AS BR AND IFR/MVFR VSBYS DEVELOP OVERNIGHT. CIGS RISE AS BR DISSIPATES TUESDAY MORNING AND THEN VFR IN THE AFTERNOON. S TO SE WINDS 4 TO 11 KTS WILL PREVAIL. GUSTS TO 40 KTS ARE POSSIBLE DUE TO OUTFLOWS FROM SHRA/TSRA. PREV DISCUSSION... /ISSUED 217 PM CDT MON JUN 22 2015/ SHORT TERM (TONIGHT THROUGH TUESDAY NIGHT)... THERE IS NOT MUCH RAIN ACTIVITY ONGOING ACROSS SOUTH-CENTRAL TEXAS THIS AFTERNOON. THERE IS ONE AREA OF LIGHT TO MODERATE RAIN REMAINING ACROSS THE EXTREME SOUTHWESTERN COUNTIES...BUT THE REST OF THE CWA REMAINS MOSTLY DRY. PRECIPITABLE WATER VALUES CONTINUE TO SLOWLY DECREASE AS A 700 MB RIDGE AXIS BUILDS INTO SOUTHEAST TEXAS FROM THE EAST. SUBSIDENCE FROM THIS SYSTEM AND SLIGHTLY DRIER AIR IS KEEPING THE COVERAGE OF ACTIVITY MUCH LESS THAN PREVIOUS DAYS. THE HRRR IS STILL FORECASTING SOME ISOLATED CONVECTION LATER THIS AFTERNOON AND WILL KEEP 20 POPS IN THE FORECAST FOR THE EVENING FOR MUCH OF THE AREA. AN UPPER LOW REMAINS JUST WEST OF THE CWA AND WILL HAVE 30 POPS THIS EVENING CLOSER TO THE RIO GRANDE TO ACCOUNT FOR BETTER LIFT IN THIS PART OF THE CWA. FOR TOMORROW...THE 700 MB RIDGE AXIS WILL REMAIN TO OUR EAST WITH THE UPPER LOW TO OUR WEST WEAKENING AND BEGINNING TO SHIFT WEST. MOISTURE VALUES WILL BE HIGH ENOUGH TO WARRANT 20 POPS FOR MUCH OF THE CWA FOR ANY CONVECTION THAT DEVELOPS IN THE WEAK SOUTHEAST FLOW. TEMPERATURES TOMORROW AFTERNOON WILL ONLY REACH THE UPPER 80S TO NEAR 90 DEGREES. HOWEVER...DEWPOINTS ARE NOT EXPECTED TO MIX OUT AND WILL REMAIN IN THE LOWER 70S. HEAT INDICES TOMORROW AFTERNOON MAY BE AS HIGH AS THE UPPER 90S. LONG TERM (WEDNESDAY THROUGH MONDAY)... WEDNESDAY/THURSDAY WILL BE A SIMILAR SETUP TO TUESDAY...BUT OUR WESTERN UPPER LOW WILL BE A NON-PLAYER WEATHER WISE. THE GULF OF MEXICO WILL REMAIN OPENED UP WITH SOUTHEAST FLOW AND AFTERNOON CONVECTION WILL REMAIN POSSIBLE MAINLY ACROSS THE SOUTHERN AND SOUTHEASTERN COUNTIES. THE UPPER RIDGE WILL STRENGTHEN OVER THE AREA FRIDAY AND THE REGION SHOULD REMAIN MOSTLY DRY. BY LATE SATURDAY AND INTO SUNDAY...THE UPPER PATTERN WILL BE SHIFTING. A STRONG RIDGE WILL AMPLIFY ACROSS THE WESTERN CONUS WITH A DEEP TROUGH OVER THE EASTERN CONUS. THIS PLACES THE CENTRAL PLAINS IN NORTHWEST FLOW BETWEEN THE SYSTEMS. MODELS ARE SHOWING A WEAK FRONTAL BOUNDARY NEARING THE CWA SATURDAY NIGHT AND SUNDAY AND WILL INCREASE POPS TO ACCOUNT FOR THIS FEATURE. WILL HAVE TO WATCH FOR POSSIBLE LOCALLY HEAVY RAINFALL GIVEN THERE WILL BE A BOUNDARY PRESENT AND DECENT MOISTURE. IT IS TOO EARLY TO GET INTO SPECIFICS BECAUSE OF MANY UNKNOWNS ON THE MESOSCALE BUT IT IS SOMETHING TO WATCH. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 90 73 90 74 89 / 20 10 20 10 20 AUSTIN BERGSTROM INTL AIRPORT 90 72 90 73 89 / 20 10 20 10 20 NEW BRAUNFELS MUNI AIRPORT 89 73 89 74 90 / 20 10 20 10 30 BURNET MUNI AIRPORT 89 72 88 73 89 / 10 10 10 10 10 DEL RIO INTL AIRPORT 89 74 89 75 91 / 20 20 20 10 10 GEORGETOWN MUNI AIRPORT 89 73 89 74 89 / 10 10 10 10 10 HONDO MUNI AIRPORT 88 73 88 74 89 / 20 10 20 10 10 SAN MARCOS MUNI AIRPORT 89 73 89 74 89 / 20 10 20 10 30 LA GRANGE - FAYETTE REGIONAL 90 74 89 75 89 / 20 10 30 10 40 SAN ANTONIO INTL AIRPORT 89 74 88 75 89 / 20 10 20 10 30 STINSON MUNI AIRPORT 89 74 89 75 90 / 20 10 20 10 30 && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...TREADWAY SYNOPTIC/GRIDS...24
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1256 AM EDT TUE JUN 23 2015 .SYNOPSIS... A WEAK COOL FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND PASS SOUTH THROUGH THE REGION OVERNIGHT INTO EARLY WEDNESDAY. DRIER HIGH PRESSURE FOLLOWS THE FRONT WEDNESDAY INTO THURSDAY BEFORE MOISTURE RETURNS BACK NORTH BY THE END OF THE WEEK. ANOTHER FRONTAL SYSTEM WILL DIP SOUTH INTO THE AREA OVER THE WEEKEND AND STALL...BRINGING BETTER CHANCES OF SHOWERS AND STORMS ALONG WITH COOLER TEMPERATURES SATURDAY INTO SUNDAY. && .NEAR TERM /THROUGH TODAY/... AS OF 918 PM EDT MONDAY... ISOLATED CONVECTION WILL DISSIPATE WITH THE LOSS OF SOLAR HEATING TONIGHT. PARTLY CLOUDY SKIES WILL PREVAIL OVERNIGHT. THE COMBINATION OF LOW LEVEL MOISTURE AND LIGHT WINDS WILL RESULT IN PATCHY FOG OVERNIGHT INTO TUESDAY MORNING. LOW TEMPERATURES WILL BE MILD WITH READINGS FROM THE MID 60S IN THE MOUNTAINS TO AROUND 70 DEGREES ACROSS THE PIEDMONT. COLD FRONT ACROSS THE OHIO VALLEY WILL SLOWLY DROP SOUTHEAST TUESDAY. AN OUTFLOW AND THE BOUNDARY WILL ENTER OUR REGION TUESDAY AFTERNOON. THESE BOUNDARY AND SOLAR HEATING WILL GENERATE SHOWERS AND THUNDERSTORMS.THE LATEST DAY 2 CONVECTIVE OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF SEVERE WEATHER. THE GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS AND HAIL WITH SOME OF THE STORMS TUESDAY AFTERNOON INTO TUESDAY EVENING. HIGHS TUESDAY WILL CLIMB IN THE MID 80S TO AROUND 90 IN THE MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICES WILL CLIMB TO AROUND 100 ROUGHLY ALONG AND EAST OF A REIDSVILLE NORTH CAROLINA TO BUCKINGHAM VIRGINIA LINE LATE IN THE AFTERNOON. RECORD HIGH TEMPERATURES ARE POSSIBLE TUESDAY. REFER TO CLIMATE SECTION FOR THE CURRENT RECORDS. AS OF 630 PM EDT MONDAY... DECREASED POPS FOR TONIGHT. MADE SOME MINOR ADJUSTMENTS IN TEMPERATURES AND CLOUD COVER FOR THIS EVENING INTO TONIGHT. AS OF 522 PM EDT MONDAY... MADE SOME MINOR ADJUSTMENTS IN POPS AND WEATHER WITH LATEST RADAR TRENDS AND BLENDED TOWARDS THE RNK WRFARW AND HRRR FOR THIS EVENING INTO TONIGHT. ALSO MODIFIED TEMPERATURES FOR THIS EVENING WITH LATEST OBS AND CONVECTION. MORE CHANGES LATER TONIGHT. AS OF 230 PM EDT MONDAY... ISOLATED SHOWERS HAVE STARTED TO DEVELOP ALONG THE CREST OF THE BLUE RIDGE IN NORTH CAROLINA...AND ALSO NORTH OF I-64. AS THE AFTERNOON CONTINUES...ADDITIONAL HEATING IS EXPECTED TO PROMPT MORE SHOWER AND THUNDERSTORM DEVELOPMENT. THE BULK OF THE CONVECTION IS EXPECTED TO BE ACROSS WESTERN INTO SOUTHERN PARTS OF THE AREA...FOLLOWING THE PATH OF THE REMNANTS OF A THUNDERSTORM COMPLEX THAT DISSIPATED OVER EASTERN KENTUCKY EARLY THIS MORNING. OVERNIGHT...THE EVENING CONVECTION IS EXPECTED TO EXIT THE REGION OR DISSIPATE COMPLETELY BY 10PM-11PM. AFTER THIS TIME...CLOUDS WILL TREND TO PARTLY CLOUDY TROUGH ROUGHLY 2-3AM TUESDAY. AFTER THIS TIME FRAME...SOME GUIDANCE HINTS AT A RESURGENCE OF LOW LEVEL MOISTURE ACROSS WESTERN PARTS OF THE REGION...SO A RETURN TO MOSTLY CLOUDY SKIES IN AREAS BETWEEN ROUGHLY BLUEFIELD TO LEWISBURG WEST VIRGINIA IS POSSIBLE. PATCHY LATE NIGHT AND EARLY MORNING FOG WILL BE POSSIBLE...ESPECIALLY IN THE RIVER AND MOUNTAIN VALLEYS WERE ANY SUBSTANTIAL PRECIPITATION FALLS THIS AFTERNOON AND EVENING. LOW TEMPERATURES WILL CONTINUE TO BE ON THE MILD SIDE. READINGS IN THE MID TO UPPER 60S ARE EXPECTED ACROSS THE MOUNTAINS WITH UPPER 60S TO AROUND 70 ACROSS THE PIEDMONT. ON TUESDAY...THE FEATURE THAT IS CURRENTLY PROGRESSING THROUGH THE GREAT LAKES REGION IS EXPECTED TO BE IMPACTING OUR WEATHER. AS THIS SYSTEM HEADS SOUTHEAST....OUTFLOW AHEAD OF IT WILL ENTER OUR REGION TOMORROW AFTERNOON. THIS BOUNDARY AND ASSOCIATED DAYTIME HEATING WILL HELP GENERATE SHOWERS AND STORMS. THE LATEST DAY 2 CONVECTIVE OUTLOOK FROM THE STORM PREDICTION CENTER OFFERS A SLIGHT RISK OF SEVERE WEATHER IN ASSOCIATION WITH THIS THUNDERSTORM ACTIVITY. THE GREATEST CONCERN WILL BE STRONG TO DAMAGING WINDS WITH SOME OF THE STORMS. OUR FORECAST WILL REFLECT AN AFTERNOON ARRIVAL...WITH THE BEST ACTIVITY ACROSS THE NORTHERN THIRD OF THE AREA BY THE LATE AFTERNOON. PORTIONS OF THE NORTH CAROLINA PIEDMONT AND FOOTHILLS MAY NEED TO WAIT UNTIL TUESDAY EVENING FOR THE ACTIVITY TO ARRIVE. TEMPERATURES ON TUESDAY ARE FORECAST TO BE THE HOTTEST OF THE WEEK THANKS TO INCREASING 850 MB TEMPS OF ABOUT 20 C IN THE WEST AND 24 C IN THE EAST. HIGHS ARE FORECAST IN THE MID 80S TO AROUND 90 IN THE MOUNTAINS TO THE MID TO UPPER 90S ACROSS THE PIEDMONT. HEAT INDICES WILL BRIEFLY TOUCH THE 100 TO 102 RANGE ROUGHLY ALONG AND EAST OF A REIDSVILLE NC TO BUCKINGHAM VA LINE LATE IN THE AFTERNOON. && .SHORT TERM /TONIGHT THROUGH THURSDAY/... AS OF 300 PM EDT MONDAY... NORTHERN STREAM ALOFT REMAINS LINED UP FROM SOUTHWEST CANADA INTO NEW ENGLAND THROUGH THURSDAY. 500 MB HEIGHTS OVER THE MID ATLANTIC REGION REMAIN CLOSE TO 590DM WITH A PIECE OF THE UPPER RIDGE STILL OVER THE SOUTHEAST UNITED STATES. WITH THIS PATTERN...LITTLE CHANGE IS EXPECTED IN THE WEATHER THROUGH THURSDAY. TEMPERATURES WILL REMAIN ABOVE NORMAL AND WITH DAILY SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS. EXTENT...SEVERITY AND TIMING OF THE PRECIPITATION WILL DEPEND ON THE CONVECTIVE COMPLEXES UPSTREAM OF THE FORECAST AREA AND WHERE THE RESIDUAL OUTFLOW BOUNDARIES ARE EACH DAY AT THE TIME OF MAXIMUM HEATING. THE SURFACE FRONT WILL BE IN THE NORTHERN PART OF THE FORECAST AREA ON TUESDAY EVENING AND SOUTH OF THE FORECAST AREA ON WEDNESDAY. THIS FRONT AND RESIDUAL OUTFLOW BOUNDARIES WILL BE THE MAIN TRIGGERS FOR SHOWERS AND THUNDERSTORMS TUESDAY NIGHT AND WEDNESDAY. NCEP FAVORS THE ECMWF SOLUTION OF A WAVE DEVELOPING ALONG THE FRONT OVER THE OHIO VALLEY THEN TRACKING INTO THE MID ATLANTIC REGION ON THURSDAY. SO THE PROBABILITY OF PRECIPITATION FOR THE AREA WILL CONTINUE. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 1247 AM EDT TUESDAY... VFR CONDITIONS WILL PREVAIL THIS EVENING INTO TONIGHT. THERE COULD BE A FEW SPOTS OF MVFR/IFR VSBYS IN THE PREFERRED RIVER AND MOUNTAIN VALLEYS DUE TO FOG/STRATUS. ALSO...GUIDANCE IS SUGGESTED A RESURGENCE OF MVFR LEVEL MOISTURE ACROSS WESTERN PARTS OF THE AREA. COULD SEE A MVFR CIG ALONG AND NEAR A KBLF-KLWB LINE. ON TUESDAY...ANY SUB-VFR CONDITIONS SHOULD IMPROVE TO VFR BY THE MID MORNING. THIS IN ADVANCE OF A WEAK COOL FRONT THAT WILL BE APPROACHING LATER IN THE DAY. ISOLATED SHOWERS OR STORMS MAY DEVELOP OR MOVE INTO THE KBLF-KLWB AREA OR PARTS WEST AROUND 19Z/3PM. THE FRONT WILL APPROACH AND THEN CROSS THE AREA TUESDAY EVENING AND OVERNIGHT. THIS SHOULD BRING INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. APPEARS BEST CHANCES REMAIN OVER THE WEST AROUND KBLF/KLWB AND ACROSS THE NE AROUND KLYH WITH LESS AT KBCB/KROA DUE TO WESTERLY FLOW. KDAN MAY SEE A LINE OF STORMS CROSS THE REGION IN THE EVENING BUT WONT INCLUDE MENTION FOR NOW GIVEN UNCERTAINTY. OTRW DELAYED TIMING OF CONVECTION AN HOUR OR TWO MOST SPOTS AND KEPT MOSTLY VICINITY MENTION AT THIS POINT. EXTENDED AVIATION DISCUSSION... MVFR SCT TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS OF AREAS OF FOG TUESDAY EVENING INTO WEDNESDAY MORNING. HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE ON TUESDAY. BELOW ARE THE CURRENT RECORDS FOR THE DATE. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...DS/KK SHORT TERM...AMS LONG TERM...AMS AVIATION...DS/JH/KK CLIMATE...CF EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1105 PM CDT MON JUN 22 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 247 PM CDT MON JUN 22 2015 CURRENTLY AS OF 19Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED SUBTROPICAL RIDGING ENCOMPASSING MUCH OF THE SOUTHERN U.S. WHILE MAINLY ZONAL FLOW WAS OVER THE NORTHERN U.S.. WITHIN THIS FLOW...A POTENT SHORTWAVE TROUGH WAS CROSSING NORTHERN MN WHILE THE SHORTWAVE THAT FORMED FROM THIS MORNINGS CONVECTION WAS OVER LOWER MI. SUBSIDENCE IN THE WAKE OF THE CONVECTIVE SHORTWAVE...COMBINED WITH CLEARING NOT OCCURRING UNTIL EARLY THIS AFTERNOON...HAS HELPED TO PREVENT ADDITIONAL CONVECTION FROM FIRING. RAP DEPICTING ANYWHERE FROM 50 TO 200 J/KG OF MLCIN. THIS WAS DESPITE A COLD FRONT TRACKING THROUGH THE FORECAST AREA ASSOCIATED WITH THE POTENT TROUGH. THAT FRONT WAS NOW LOCATED FROM NORTHEAST WISCONSIN THROUGH SOUTHWEST IOWA. MUCH DRIER AIR FLOWING IN BEHIND THE FRONT...NOTED BY PRECIPITABLE WATER IN THE 2 INCH RANGE OVER SOUTHEAST IOWA TO 0.5-0.75 INCHES IN THE DAKOTAS AND CENTRAL MN. SOME STRATOCUMULUS DEVELOPMENT HAS OCCURRED IMMEDIATELY BEHIND THE FRONT AS WELL...ASSOCIATED WITH MOISTURE TRAPPED IN THE COLD FRONTAL INVERSION. TEMPERATURES ARE MOSTLY IN THE 70S TO LOWER 80S. MUCH QUIETER SHORT TERM PERIOD EXPECTED. THE POTENT SHORTWAVE TROUGH OVER MN WILL CONTINUE ITS MARCH QUICKLY EASTWARD TOWARDS EASTERN ONTARIO BY 12Z TUE. EXPECT SUBSIDENCE AND DRYING TO SPREAD INTO THE FORECAST AREA THIS EVENING BEHIND THE TROUGHS COLD FRONTAL PASSAGE. THAT FRONT SHOULD CLEAR THE AREA BY 00Z...TAKING ANY CONVECTION CHANCES WITH IT...WHICH ARE MINIMAL DUE TO ALL OF THE MLCIN...LACK OF CONVERGENCE ALONG THE FRONT AND BEING IN THE RIGHT EXIT REGION OF A 100KT JET CORE TRACKING INTO NORTHERN WI. MAY STILL HAVE TO DEAL WITH SOME POST-FRONTAL STRATOCUMULUS...BUT THAT TOO SHOULD CLEAR BY 06Z AS DRIER AIR CONTINUES TO WORK IN. ALL OF TUESDAY LOOKS TO REMAIN DRY...THOUGH SOME MID CLOUDS SHOULD SPREAD ACROSS THE AREA DURING THE DAY ASSOCIATED WITH MID LEVEL FRONTOGENESIS. WINDS WILL GRADUALLY DIMINISH DURING THE NIGHT AS HIGH PRESSURE BUILDS IN. COULD SEE SOME PATCHY FOG DEVELOP IN OUR TYPICAL COLD SPOTS AS A RESULT WITH WINDS DECOUPLING THERE AND RECENT RAIN...BUT ENOUGH WIND LOOKS TO CONTINUE TO PREVENT FOG ELSEWHERE. LOWS IN THE 50S TO LOW 60S PER GUIDANCE SEEMS REASONABLE. 925MB TEMPS OF 16-18C ON TUESDAY SHOULD RESULT IN HIGHS IN THE 70S WITH A FEW LOW 80S POSSIBLE IN RIVER VALLEYS. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 247 PM CDT MON JUN 22 2015 MUCH OF THE LONG TERM PERIOD THE FORECAST AREA RESIDES IN NORTHWEST FLOW ALOFT...WHICH BECOMES EVEN MORE NORTHERLY FOR THE WEEKEND INTO EARLY NEXT WEEK AS ANAMOUSLY STRONG SUBTROPICAL RIDGING BUILDS OVER THE WESTERN U.S.. THIS TYPE OF PATTERN WILL HOLD TEMPERATURES AT OR BELOW SEASONABLE NORMS. ON THE PRECIPITATION SIDE OF THINGS...A COUPLE OF TIME PERIODS OF CONCERN... 1. WEDNESDAY. A SHORTWAVE COMING OUT OF NEBRASKA AND SOUTH DAKOTA LOOKS TO TRACK INTO ILLINOIS. THIS SHORTWAVE WILL HELP TO PULL THE CURRENT FRONTAL BOUNDARY...WHICH STALLS NEAR I-70 ON TUESDAY...BACK NORTHWARD. THE QUESTION IS HOW FAR NORTH. THE ECMWF IS FARTHEST SOUTH...HOLDING IT OVER NORTHERN MO...WHILE THE GFS...NAM AND CANADIAN PULL IT AT LEAST TO I-80. SHOWERS AND THUNDERSTORMS... ISENTROPICALLY AND FRONTOGENETICALLY DRIVEN ON ITS NORTH SIDE...MAY TRY TO MAKE A RUN TOWARDS THE FORECAST AREA. HOWEVER...CONVECTIVE OUTFLOWS FROM THE PRECIPITATION MAY TEND TO HOLD THE FRONT BACK. ADDITIONALLY...THE FRONT IS PARALLEL TO THE UPPER FLOW WHICH ISNT GOOD FOR LIFTING IT NORTHWARD. THEREFORE...HAVE TRENDED PRECIPITATION CHANCES DOWN WITH THE HIGHEST CHANCES IN NORTHEAST IOWA CLOSEST TO THE FRONTAL BOUNDARY. 2. WEDNESDAY NIGHT INTO THURSDAY. ANOTHER SERIES OF SHORTWAVES ARE PROGGED TO COME OUT OF THE DAKOTAS THROUGH THE FORECAST AREA. HOW MUCH PRECIPITATION THEY PRODUCE WILL DEPEND ON HOW FAR NORTH THAT WARM FRONTAL BOUNDARY GETS ON WEDNESDAY. LIKE THE MODEL SPREAD ON WEDNESDAY...THE ECMWF REMAINS THE FARTHEST SOUTH WHILE THE NAM AND ESPECIALLY THE GFS AND CANADIAN ARE FARTHER NORTH. THE LATTER 3 MODELS PRODUCE MUCH MORE CONVECTION AND PRECIPITATION FOR US WHILE THE ECMWF IS NEARLY DRY WITH ITS CONVECTION SOUTH OF THE FORECAST AREA. GIVEN THE NAM/GFS/CANADIAN BIAS OVERALL THIS YEAR TO BE TOO FAR NORTH...THE NORTHWEST FLOW PATTERN AND CONVECTIVE OUTFLOWS HOLDING UP THE FRONT...FEEL A MORE SOUTHERN TRACK OF THE ECMWF IS MORE LIKELY TO OCCUR. THEREFORE...PRECIPITATION CHANCES FOR THE MOST PART ARE IN THE 20-50 RANGE. HARD TO GET TOO EXCITED ABOUT ANY SEVERE CHANCES GIVEN THIS SPREAD IN CONVECTION LOCATION AS WELL. 3. BEYOND THURSDAY THROUGH EARLY NEXT WEEK. MODELS ARE DRIVING MULTIPLE SHORTWAVES DOWN ACROSS THE FORECAST AREA. PROBLEM IS THE MOISTURE AS THE MAIN FRONTAL BOUNDARY AFTER THE SHORTWAVES PASS ON THURSDAY GETS SHUNTED DOWN TO THE GULF COAST. NEW 22.12Z ECMWF REALLY HAS BACKED OFF ON PRECIPITATION AND DEPICTS MONDAY AS THE ONLY TIME PERIOD OF SEEING SOME PRECIPITATION. MEANWHILE...THE 22.12Z GFS/CANADIAN BOTH WANT TO KEEP THE AREA GETTING HIT BY SPORADIC SHOWERS/STORMS WITH THE SHORTWAVES. IT APPEARS THESE MODELS MAY BE PRODUCING TOO MUCH EVAPOTRANSPIRATION TO BOOST UP BOUNDARY LAYER MOISTURE. THEREFORE...CHANCES OF PRECIPITATION FOR THE REST OF THE FORECAST HAVE BEEN TRENDED DOWNWARD. LATER FORECASTS SHOULD BE ABLE TO GIVE SOME DRY PERIODS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1105 PM CDT MON JUN 22 2015 WEAK HIGH PRESSURE BUILDS ACROSS THE REGION TONIGHT...AND WILL BE THE MAIN WEATHER INFLUENCE THROUGH TUE. LOOK FOR VFR CONDITIONS AS A RESULT WITH SKC/SCT SKIES. WINDS WILL STAY WEST/NORTHWEST TONIGHT- TUE...BECOMING MORE LIGHT AND SOUTHERLY TUE EVENING. FOG COULD BECOME A CONCERN OVERNIGHT TUE. DEEP LIGHT WIND FIELD COUPLED WITH MOSTLY CLEAR SKIES AND RECENT RAINS SETS UP PRETTY WELL FOR AREAS OF FOG...NOT JUST A FAVORABLE VALLEY FOG SCENARIO FOR KLSE. SOME CLOUDS COULD FILTER IN FROM THE WEST...LIMITING THE FOG. THIS WILL HAVE TO BE MONITORED CLOSELY AS WORST CASE SCENARIO WOULD RESULT IN WIDESPREAD SUB 1SM BR/FG. && .HYDROLOGY... ISSUED AT 247 PM CDT MON JUN 22 2015 THE STORMS FROM THIS MORNING HIT MUCH OF THE UPPER IOWA RIVER BASIN AND NORTHERN PORTION OF THE CEDAR RIVER BASIN PRETTY HARD. COMBINATION OF RADAR AND OBSERVATIONS SHOWED ANYWHERE FROM 3 TO 5 INCHES. THE NORTHERN END OF THE TURKEY AND SOUTHERN END OF THE KICKAPOO ALSO GOT HIT WITH 1 TO 2 INCHES OF RAIN. AS A RESULT...THESE RIVERS ARE RISING WITH SOME FLOOD WARNINGS OUT. SINCE THEY ARE QUICK RESPONDING...MOST SHOULD DROP BELOW FLOOD STAGE IN THE NEXT 1 TO 2 DAYS...ESPECIALLY GIVEN LITTLE OR NO ADDITIONAL RAINFALL EXPECTED. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION....RIECK HYDROLOGY...AJ
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1034 AM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE REGION LATE TODAY. WEAK HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR TONIGHT AND WEDNESDAY. LOW PRESSURE IN THE MIDWEST ON THURSDAY WILL BE MOVE EAST AND CROSS THE AREA ON FRIDAY. ADDITIONAL LOW PRESSURE FROM THE OHIO VALLEY WILL MOVE EASTWARD THROUGH OR SOUTH OF THE AREA OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1030AM UPDATE...SEVERE THUNDERSTORM WATCH ISSUED FOR THE NORTHERN 2/3RDS OF THE CWA...#342...IN AFFECT 700PM. AN ADDITIONAL WATCH IS POSSIBLE FURTHER SOUTH LATER THIS AFTERNOON. 900AM UPDATE...THE WEAKENING MCS IS ENTERING THE POCONOS AT THIS TIME. LIGHTNING IS ON THE DECREASE AS IS THE SEVER THREAT. COVERING WITH AN SPS FOR SOME GUSTY WINDS AND BRIEF HEAVY RAINFALL. WITH THIS FEATURE HOLDING TOGETHER, MID-MORNING POPS HAVE BEEN BUMPED UP ACROSS THE SOUTHERN POCONOS AND NORTHWEST NJ. ALSO TWEAKED THE SKY COVER TO ACCOUNT FOR MORE CLOUDS UP NORTH. THE HEADLINES FOR THIS AFTERNOON HAVEN`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`T RULE OUT SOME HAIL BEING POSSIBLE. THE MAIN HAZARD THOUGH LOOKS TO BE STRONG WINDS. GIVEN A WIND PROFILE THAT IS ALMOST UNIDIRECTIONAL A MID LEVEL JET, STRONG WINDS COULD EASILY MIX DOWN WITH STRONGER STORMS. AS MENTIONED BY THE PREVIOUS SHIFT, GIVEN THE FAST STORM MOTIONS, FLASH FLOOD THREAT APPEARS TO BE QUITE LOW AT THIS TIME. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... GENERALLY WENT BELOW THE MOS POP VALUES OVER NIGHT AS I THINK THE FRONT WILL BE MOSTLY IF NOT ENTIRELY THROUGH THE REGION BY 00Z. OTHERWISE, BEHIND THE FRONT, THE MAIN STORY WILL BE DRY AND COLD AIR ADVECTION. DEPENDING ON HOW QUICKLY THE FRONT WILL SWEEP THROUGH, COULD SEE WIDESPREAD DEW POINTS IN THE 50S AND LOWER 60S, AND LOWS GENERALLY IN THE 60S. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE EXTENDD FCST STARTS OFF DRY AND PLEASANT AND THEN HAS QUITE A BIT OF UNCERTAINTY IN IT AFTER THAT. HIGH PRES WILL BE OVER THE REGION ON WED AND EXPECT A SUNNY DAY WITH PLEASANT TEMPS AND NWLY FLOW AFTER THE PASSAGE OF THE CDFNT LATE TUE. THIS HIGH WILL GRADUALLY MOVE EWD WED NIGHT BUT STILL EXPECT DRY WX, BUT WITH INCREASING CLOUDS. ON THU, AN AREA OF LOW PRES OVER THE MIDWEST WILL MOVE EWD AND BY LATER THU WILL BRING SOME PRECIP CHCS TO THE AREA. AS IS OFTEN THE CASE, THE GFS IS A BIT FASTER THAN THE ECMWF. THE NAM IS EVEN A BIT SLOWER, WITH NOTHING BEFORE 26/00Z. THE GUID IS SUGGESTING ATTM THAT THE BEST PRECIP CHCS WOULD BE S. THEN, AFTER THIS LOW MOVES BY, WE SHUD GET AT LEAST A PARTIAL BREAK ON FRI, ESPECIALLY FOR NRN AREAS. AFTER FRI, CONFIDENCE DROPS TREMENDOUSLY. A MAJOR PATN SHIFT IS ALSO IN THE WORKS WHICH ALSO HELPS EXPLAIN THE DROP IN FCST CONFIDENCE. WE WILL GO FROM ZONAL FLOW WHICH WE HAVE BEEN IN FOR WEEKS TO A MAJOR RIDGE IN THE W AND ALMOST UNSEASONABLE TROF IN THE E BY THE WEEKEND. THE GUID AGREES THAT LOW PRES WILL MOVE FROM THE OHIO VLY EWD. HOWEVER, THE GFS AND MOST OF THE MDLS ARE FURTHER N WITH THE PRECIP SHIELD AND KEEP FRI NIGHT THRU ERLY SUN IN DECENT CHCS FOR SHOWERS. ON THE OTHER HAND, THE ECMWF IS FURTHER S WITH THE LOW AND WITH THE EXCEPTION OF SRN AREAS, MUCH OF THIS PD WOULD BE DRY. THE CMC HAS DIFFERENT TIMING. SLOWER TO MOVE THE PRECIP IN ON SAT. LINGERS IT LONGER ON SUN.... SO FOR NOW, WILL JUST KEEP CHC POPS. IT STILL SEEMS THAT PRECIP CHCS ARE BETTER SAT THAN SUN AS BOTH THE GFS AND ECMWF HAVE LOW PRES DEPARTING THE AREA ON SUN. SMALL PRECIP CHCS REMAIN ON MON, BUT IT CUD END UP BEING DRY. TEMPS WILL START OUT NR NRML AND END UP MUCH BELOW NRML OVER THE WEEKEND AS E TO NE ONSHORE FLOW PREVAILS. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. FOR THE 12Z TAFS...MOSTLY VFR CONDITIONS ARE EXPECTED. THE EXCEPTION WILL BE WITH ANY THUNDERSTORMS THAT DEVELOP WHICH ARE LIKELY TO AFFECT ALL OF TAF SITES LATER TODAY. THERE ARE TWO WINDOWS OF POTENTIAL TSRA. FIRST, A MESOSCALE CONVECTIVE COMPLEX SLIDING OUT OF WESTERN PA, COULD ARRIVE IN OUR AREA BY MID DAY. SECOND, STORMS COULD DEVELOP ALONG THE COLD FRONT THIS AFTERNOON. HOWEVER, IT SHOULD BE NOTED THAT TIMING OF THE FRONT IS STILL UNCERTAIN (ONE MODEL, THE NAM, IS AS MUCH AS 6 HOURS SLOWER THAN THE REST OF THE MODEL CONSENSUS). HAVE CHOSEN TO GO WITH TIMING SHOWN FOR THE GFS GUIDANCE, WHICH HAS BEEN THE MOST CONSISTENT RUN TO RUN. WITH ANY STORMS THAT DEVELOP, COULD SEE BRIEF IFR CONDITIONS AND VARIABLE AND GUSTY WINDS. FOR NOW WIND GUSTS TO 35KT WERE INCLUDED IN THE TAFS, BUT WIND GUSTS NEAR OR ABOVE 50 KT WILL BE POSSIBLE WITH THE STRONGEST STORMS. ONCE THE FRONT ARRIVES, SHOULD SEE CONDITIONS QUICKLY RETURN TO VFR, AND WILL ALSO SEE A WIND SHIFT TO NORTHWESTERLY. OUTLOOK... WED ...VFR. HIGH PRES. W TO NW WIND 10 TO 15 KT IN THE AFTN. HIGH CONFIDENCE. THU AND FRI...VFR CONDS ERLY THU THEN LOWERING CIGS BY LATER THU AND INTO THU NIGHT INTO FRI. MVFR AND IFR PSBL IF NOT LIKELY IN SHRA AND FG. GRADUALLY LOWERING TO MVFR WITH POSSIBLE IFR CONDS THURSDAY NIGHT IN SHOWERS/ST/FOG. SLY WIND SHIFT TO NE. LOW CONFIDENCE. SAT...E-NE GUSTS 20 KT. A SERIES OF LOW PRES SYS CUD IMPACT THE REGION OR REMAIN S. CONFIDENCE IS VERY LOW, BUT THERE COULD BE MVFR/IFR CONDS AND SHRA/FG FOR AT LEAST A PORTION OF SAT. && .MARINE... SOUTHWESTERLY WINDS NEAR 25KT WILL BUILD BY MID DAY, WITH SEAS BUILDING NEAR 5 FT IN RESPONSE. THUS SCA CONDITIONS ARE LIKELY FROM MID DAY INTO LATE AFTERNOON ON THE BAY, AND EARLY EVENING ON THE ATLANTIC WATERS (WHERE SEAS MAY BE A BIT SLOWER TO DECREASE. OUTLOOK... WED THRU FRI...LTST FCST HAS WIND AND SEAS REMAINING BELOW SCA CRITERIA. FRI NIGHT THRU SAT...SCA LIKELY. SEAS SHOULD BUILD TO 7 TO 8 FEET ON E TO NE FETCH. GUSTS AROUND 25 TO 30 KT AND PSBLY HIGHER. && .RIP CURRENTS... THERE IS A MODERATE RISK FOR RIP CURRENTS ALONG THE NEW JERSEY COAST AND LOW RISK FOR DELAWARE. IN HOUSE PROCEDURE WAS A MODERATE, WHILE GRIDDED CALCULATION WAS LOW. GIVEN THE WIND SCENARIO, THE MORNING MAY START WITH LOW RISKS EVERYWHERE AND THEN INCREASE TO MODERATE AS THE DAY PROGRESSES. && .CLIMATE... PHILADELPHIA HEAT WAVE CULMINATES WITH POSSIBLE NEAR RECORD WARMTH THIS AFTERNOON. TUESDAY JUNE 23 RECORDS: IN ALL PROBABILITY WILL REMAIN BELOW ALL VALUES LISTED BELOW, BUT COULD BE ESPECIALLY CLOSE AT KGED AND POSSIBLY OTHERS. KACY 98-1988 KILG 100-1894 KPHL 97-1888 KABE 95-1965 KTTN 97-1894 KRDG 96-1908 KMPO 90-1908 KGED 100-1988 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ070-071-102- 104-106. NJ...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR NJZ015-017>019. DE...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR DEZ001. MD...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR MDZ008. MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430- 431. && $$ SYNOPSIS...NIERENBERG NEAR TERM...JOHNSON/KRUZDLO SHORT TERM...JOHNSON LONG TERM...NIERENBERG AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG RIP CURRENTS... CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
913 AM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE REGION LATE TODAY. WEAK HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR TONIGHT AND WEDNESDAY. LOW PRESSURE IN THE MIDWEST ON THURSDAY WILL BE MOVE EAST AND CROSS THE AREA ON FRIDAY. ADDITIONAL LOW PRESSURE FROM THE OHIO VALLEY WILL MOVE EASTWARD THROUGH OR SOUTH OF THE AREA OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 900AM UPDATE...THE WEAKENING MCS IS ENTERING THE POCONOS AT THIS TIME. LIGHTNING IS ON THE DECREASE AS IS THE SEVER THREAT. COVERING WITH AN SPS FOR SOME GUSTY WINDS AND BRIEF HEAVY RAINFALL. WITH THIS FEATURE HOLDING TOGETHER, MID-MORNING POPS HAVE BEEN BUMPED UP ACROSS THE SOUTHERN POCONOS AND NORTHWEST NJ. ALSO TWEAKED THE SKY COVER TO ACCOUNT FOR MORE CLOUDS UP NORTH. THE HEADLINES FOR THIS AFTERNOON HAVEN`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`T RULE OUT SOME HAIL BEING POSSIBLE. THE MAIN HAZARD THOUGH LOOKS TO BE STRONG WINDS. GIVEN A WIND PROFILE THAT IS ALMOST UNIDIRECTIONAL A MID LEVEL JET, STRONG WINDS COULD EASILY MIX DOWN WITH STRONGER STORMS. AS MENTIONED BY THE PREVIOUS SHIFT, GIVEN THE FAST STORM MOTIONS, FLASH FLOOD THREAT APPEARS TO BE QUITE LOW AT THIS TIME. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... GENERALLY WENT BELOW THE MOS POP VALUES OVER NIGHT AS I THINK THE FRONT WILL BE MOSTLY IF NOT ENTIRELY THROUGH THE REGION BY 00Z. OTHERWISE, BEHIND THE FRONT, THE MAIN STORY WILL BE DRY AND COLD AIR ADVECTION. DEPENDING ON HOW QUICKLY THE FRONT WILL SWEEP THROUGH, COULD SEE WIDESPREAD DEW POINTS IN THE 50S AND LOWER 60S, AND LOWS GENERALLY IN THE 60S. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE EXTENDD FCST STARTS OFF DRY AND PLEASANT AND THEN HAS QUITE A BIT OF UNCERTAINTY IN IT AFTER THAT. HIGH PRES WILL BE OVER THE REGION ON WED AND EXPECT A SUNNY DAY WITH PLEASANT TEMPS AND NWLY FLOW AFTER THE PASSAGE OF THE CDFNT LATE TUE. THIS HIGH WILL GRADUALLY MOVE EWD WED NIGHT BUT STILL EXPECT DRY WX, BUT WITH INCREASING CLOUDS. ON THU, AN AREA OF LOW PRES OVER THE MIDWEST WILL MOVE EWD AND BY LATER THU WILL BRING SOME PRECIP CHCS TO THE AREA. AS IS OFTEN THE CASE, THE GFS IS A BIT FASTER THAN THE ECMWF. THE NAM IS EVEN A BIT SLOWER, WITH NOTHING BEFORE 26/00Z. THE GUID IS SUGGESTING ATTM THAT THE BEST PRECIP CHCS WOULD BE S. THEN, AFTER THIS LOW MOVES BY, WE SHUD GET AT LEAST A PARTIAL BREAK ON FRI, ESPECIALLY FOR NRN AREAS. AFTER FRI, CONFIDENCE DROPS TREMENDOUSLY. A MAJOR PATN SHIFT IS ALSO IN THE WORKS WHICH ALSO HELPS EXPLAIN THE DROP IN FCST CONFIDENCE. WE WILL GO FROM ZONAL FLOW WHICH WE HAVE BEEN IN FOR WEEKS TO A MAJOR RIDGE IN THE W AND ALMOST UNSEASONABLE TROF IN THE E BY THE WEEKEND. THE GUID AGREES THAT LOW PRES WILL MOVE FROM THE OHIO VLY EWD. HOWEVER, THE GFS AND MOST OF THE MDLS ARE FURTHER N WITH THE PRECIP SHIELD AND KEEP FRI NIGHT THRU ERLY SUN IN DECENT CHCS FOR SHOWERS. ON THE OTHER HAND, THE ECMWF IS FURTHER S WITH THE LOW AND WITH THE EXCEPTION OF SRN AREAS, MUCH OF THIS PD WOULD BE DRY. THE CMC HAS DIFFERENT TIMING. SLOWER TO MOVE THE PRECIP IN ON SAT. LINGERS IT LONGER ON SUN.... SO FOR NOW, WILL JUST KEEP CHC POPS. IT STILL SEEMS THAT PRECIP CHCS ARE BETTER SAT THAN SUN AS BOTH THE GFS AND ECMWF HAVE LOW PRES DEPARTING THE AREA ON SUN. SMALL PRECIP CHCS REMAIN ON MON, BUT IT CUD END UP BEING DRY. TEMPS WILL START OUT NR NRML AND END UP MUCH BELOW NRML OVER THE WEEKEND AS E TO NE ONSHORE FLOW PREVAILS. && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. FOR THE 12Z TAFS...MOSTLY VFR CONDITIONS ARE EXPECTED. THE EXCEPTION WILL BE WITH ANY THUNDERSTORMS THAT DEVELOP WHICH ARE LIKELY TO AFFECT ALL OF TAF SITES LATER TODAY. THERE ARE TWO WINDOWS OF POTENTIAL TSRA. FIRST, A MESOSCALE CONVECTIVE COMPLEX SLIDING OUT OF WESTERN PA, COULD ARRIVE IN OUR AREA BY MID DAY. SECOND, STORMS COULD DEVELOP ALONG THE COLD FRONT THIS AFTERNOON. HOWEVER, IT SHOULD BE NOTED THAT TIMING OF THE FRONT IS STILL UNCERTAIN (ONE MODEL, THE NAM, IS AS MUCH AS 6 HOURS SLOWER THAN THE REST OF THE MODEL CONSENSUS). HAVE CHOSEN TO GO WITH TIMING SHOWN FOR THE GFS GUIDANCE, WHICH HAS BEEN THE MOST CONSISTENT RUN TO RUN. WITH ANY STORMS THAT DEVELOP, COULD SEE BRIEF IFR CONDITIONS AND VARIABLE AND GUSTY WINDS. FOR NOW WIND GUSTS TO 35KT WERE INCLUDED IN THE TAFS, BUT WIND GUSTS NEAR OR ABOVE 50 KT WILL BE POSSIBLE WITH THE STRONGEST STORMS. ONCE THE FRONT ARRIVES, SHOULD SEE CONDITIONS QUICKLY RETURN TO VFR, AND WILL ALSO SEE A WIND SHIFT TO NORTHWESTERLY. OUTLOOK... WED ...VFR. HIGH PRES. W TO NW WIND 10 TO 15 KT IN THE AFTN. HIGH CONFIDENCE. THU AND FRI...VFR CONDS ERLY THU THEN LOWERING CIGS BY LATER THU AND INTO THU NIGHT INTO FRI. MVFR AND IFR PSBL IF NOT LIKELY IN SHRA AND FG. GRADUALLY LOWERING TO MVFR WITH POSSIBLE IFR CONDS THURSDAY NIGHT IN SHOWERS/ST/FOG. SLY WIND SHIFT TO NE. LOW CONFIDENCE. SAT...E-NE GUSTS 20 KT. A SERIES OF LOW PRES SYS CUD IMPACT THE REGION OR REMAIN S. CONFIDENCE IS VERY LOW, BUT THERE COULD BE MVFR/IFR CONDS AND SHRA/FG FOR AT LEAST A PORTION OF SAT. && .MARINE... SOUTHWESTERLY WINDS NEAR 25KT WILL BUILD BY MID DAY, WITH SEAS BUILDING NEAR 5 FT IN RESPONSE. THUS SCA CONDITIONS ARE LIKELY FROM MID DAY INTO LATE AFTERNOON ON THE BAY, AND EARLY EVENING ON THE ATLANTIC WATERS (WHERE SEAS MAY BE A BIT SLOWER TO DECREASE. OUTLOOK... WED THRU FRI...LTST FCST HAS WIND AND SEAS REMAINING BELOW SCA CRITERIA. FRI NIGHT THRU SAT...SCA LIKELY. SEAS SHOULD BUILD TO 7 TO 8 FEET ON E TO NE FETCH. GUSTS AROUND 25 TO 30 KT AND PSBLY HIGHER. && .RIP CURRENTS... THERE IS A MODERATE RISK FOR RIP CURRENTS ALONG THE NEW JERSEY COAST AND LOW RISK FOR DELAWARE. IN HOUSE PROCEDURE WAS A MODERATE, WHILE GRIDDED CALCULATION WAS LOW. GIVEN THE WIND SCENARIO, THE MORNING MAY START WITH LOW RISKS EVERYWHERE AND THEN INCREASE TO MODERATE AS THE DAY PROGRESSES. && .CLIMATE... PHILADELPHIA HEAT WAVE CULMINATES WITH POSSIBLE NEAR RECORD WARMTH THIS AFTERNOON. TUESDAY JUNE 23 RECORDS: IN ALL PROBABILITY WILL REMAIN BELOW ALL VALUES LISTED BELOW, BUT COULD BE ESPECIALLY CLOSE AT KGED AND POSSIBLY OTHERS. KACY 98-1988 KILG 100-1894 KPHL 97-1888 KABE 95-1965 KTTN 97-1894 KRDG 96-1908 KMPO 90-1908 KGED 100-1988 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR PAZ070-071-102- 104-106. NJ...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR NJZ015-017>019. DE...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR DEZ001. MD...HEAT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR MDZ008. MARINE...SMALL CRAFT ADVISORY UNTIL 11 PM EDT THIS EVENING FOR ANZ450>455. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430- 431. && $$ SYNOPSIS...NIERENBERG NEAR TERM...JOHNSON/KRUZDLO SHORT TERM...JOHNSON LONG TERM...NIERENBERG AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG RIP CURRENTS... CLIMATE...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
635 AM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL MOVE THROUGH THE REGION LATE TODAY. WEAK HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT FOR TONIGHT AND WEDNESDAY. LOW PRESSURE IN THE MIDWEST ON THURSDAY WILL BE MOVE EAST AND CROSS THE AREA ON FRIDAY. ADDITIONAL LOW PRESSURE FROM THE OHIO VALLEY WILL MOVE EASTWARD THROUGH OR SOUTH OF THE AREA OVER THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 630AM UPDATE...AN MCS ACROSS WESTERN PA CONTINUES TO MAKE FAST PROGRESS SOUTHEAST. THE HRRR IS NOW SHOWING THIS ARRIVING IN OUR CWA AS EARLY AS 15Z (BY CURRENT RADAR TRENDS IT WOULD ARRIVE EARLIER, BUT EXPECT FORWARD SPEED TO SLOW AS DIURNAL MIXING AND ENHANCED SOUTHWESTERLY FLOW AHEAD OF THE SYSTEM DEVELOP). THIS MCS IS NOT ON THE FRONT, RATHER CONSIDERABLY AHEAD OF IT, BUT IF IT CONTINUES ITS PROGRESS AND ARRIVES IN OUR CWA BY MID DAY, THIS WOULD LIMIT CONVECTIVE INITIATION LATER ALONG THE FRONT. FOR NOW, HAVE POPS BROAD ENOUGH TO COVER EITHER SCENARIO, BUT WILL CONTINUE TO WATCH THIS CLOSELY. PREVIOUS NEAR TERM DISCUSSION...STILL SOME UNCERTAINTY IN THE TIMING OF THE FRONT (AND THUS THUNDERSTORMS) TODAY. IN FACT THE 00Z RUN OF THE NAM WAS ALMOST 6 HOURS SLOWER THAN THE GFS WHICH HAS BEEN PRETTY CONSISTENT RUN TO RUN AT CLEARING THE FRONT OFF THE SHORE BY 00Z. BY SATELLITE IMAGERY, IT LOOKS LIKE THE UPPER LEVEL SHORT WAVE TROUGH (NOW OVER THE NORTHERN GREAT LAKES REGION) HAS BEEN RATHER PROGRESSIVE OVER THE LAST SEVERAL HOURS, AND THE 00Z RAOBS INDICATE MODEST HEIGHT FALLS AHEAD OF THE TROUGH, SO SEE LITTLE REASON TO GO WITH THE SLOWER SOLUTION. THE FIRST THREAT OF THE DAY WILL BE THE HEAT, PRIMARILY IN THE URBAN CORRIDOR FROM WILMINGTON TO TRENTON. FOR THE DELMARVA PENINSULA, CONDITIONS WILL BE CLOSE, BUT HAVE HEAT INDEX VALUES FALLING JUST SHORT OF CRITERIA AS IT APPEARS THE MODELS MAY BE UNDERESTIMATING THE MIXING EARLY IN THE DAY. AS FOR THE SEVERE THREAT, STILL LOOKING AT CONSIDERABLE INSTABILITY BY MID AFTERNOON (CAPE VALUES ON THE ORDER OF 2000 J/KG). MODEL SHEAR VALUES HAVE DECREASED SLIGHTLY FROM PREVIOUS RUNS (AROUND 30 KT VS THE 40 KT WE SAW WITH YESTERDAYS MODEL SOUNDINGS), BUT IS STILL SUFFICIENT TO SUPPORT SUSTAINED UPDRAFTS. SOUTHWESTERLY WINDS IN THE BOUNDARY LAYER WILL LEAD TO INCREASING LAPSE RATES. THERE DOES APPEAR THAT A MODEST MID LEVEL CAP WILL BE IN PLACE, AT LEAST THROUGH EARLY AFTERNOON, IF NOT LATER, BUT STILL EXPECT CONVECTIVE TEMPERATURE TO BE REACHED. THE VERY HIGH MELTING LAYER WILL LIKELY SOMEWHAT LIMIT THE LARGE HAIL THREAT, BUT GIVEN HOW HIGH THE EQUILIBRIUM LEVEL WILL BE, CAN`T RULE OUT SOME HAIL BEING POSSIBLE. THE MAIN HAZARD THOUGH LOOKS TO BE STRONG WINDS. GIVEN A WIND PROFILE THAT IS ALMOST UNIDIRECTIONAL A MID LEVEL JET, STRONG WINDS COULD EASILY MIX DOWN WITH STRONGER STORMS. AS MENTIONED BY THE PREVIOUS SHIFT, GIVEN THE FAST STORM MOTIONS, FLASH FLOOD THREAT APPEARS TO BE QUITE LOW AT THIS TIME. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... GENERALLY WENT BELOW THE MOS POP VALUES OVER NIGHT AS I THINK THE FRONT WILL BE MOSTLY IF NOT ENTIRELY THROUGH THE REGION BY 00Z. OTHERWISE, BEHIND THE FRONT, THE MAIN STORY WILL BE DRY AND COLD AIR ADVECTION. DEPENDING ON HOW QUICKLY THE FRONT WILL SWEEP THROUGH, COULD SEE WIDESPREAD DEW POINTS IN THE 50S AND LOWER 60S, AND LOWS GENERALLY IN THE 60S. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE EXTENDD FCST STARTS OFF DRY AND PLEASANT AND THEN HAS QUITE A BIT OF UNCERTAINTY IN IT AFTER THAT. HIGH PRES WILL BE OVER THE REGION ON WED AND EXPECT A SUNNY DAY WITH PLEASANT TEMPS AND NWLY FLOW AFTER THE PASSAGE OF THE CDFNT LATE TUE. THIS HIGH WILL GRADUALLY MOVE EWD WED NIGHT BUT STILL EXPECT DRY WX, BUT WITH INCREASING CLOUDS. ON THU, AN AREA OF LOW PRES OVER THE MIDWEST WILL MOVE EWD AND BY LATER THU WILL BRING SOME PRECIP CHCS TO THE AREA. AS IS OFTEN THE CASE, THE GFS IS A BIT FASTER THAN THE ECMWF. THE NAM IS EVEN A BIT SLOWER, WITH NOTHING BEFORE 26/00Z. THE GUID IS SUGGESTING ATTM THAT THE BEST PRECIP CHCS WOULD BE S. THEN, AFTER THIS LOW MOVES BY, WE SHUD GET AT LEAST A PARTIAL BREAK ON FRI, ESPECIALLY FOR NRN AREAS. AFTER FRI, CONFIDENCE DROPS TREMENDOUSLY. A MAJOR PATN SHIFT IS ALSO IN THE WORKS WHICH ALSO HELPS EXPLAIN THE DROP IN FCST CONFIDENCE. WE WILL GO FROM ZONAL FLOW WHICH WE HAVE BEEN IN FOR WEEKS TO A MAJOR RIDGE IN THE W AND ALMOST UNSEASONABLE TROF IN THE E BY THE WEEKEND. THE GUID AGREES THAT LOW PRES WILL MOVE FROM THE OHIO VLY EWD. HOWEVER, THE GFS AND MOST OF THE MDLS ARE FURTHER N WITH THE PRECIP SHIELD AND KEEP FRI NIGHT THRU ERLY SUN IN DECENT CHCS FOR SHOWERS. ON THE OTHER HAND, THE ECMWF IS FURTHER S WITH THE LOW AND WITH THE EXCEPTION OF SRN AREAS, MUCH OF THIS PD WOULD BE DRY. THE CMC HAS DIFFERENT TIMING. SLOWER TO MOVE THE PRECIP IN ON SAT. LINGERS IT LONGER ON SUN.... SO FOR NOW, WILL JUST KEEP CHC POPS. IT STILL SEEMS THAT PRECIP CHCS ARE BETTER SAT THAN SUN AS BOTH THE GFS AND ECMWF HAVE LOW PRES DEPARTING THE AREA ON SUN. SMALL PRECIP CHCS REMAIN ON MON, BUT IT CUD END UP BEING DRY. TEMPS WILL START OUT NR NRML AND END UP MUCH BELOW NRML OVER THE WEEKEND AS E TO NE ONSHORE FLOW PREVAILS. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. FOR THE 12Z TAFS...MOSTLY VFR CONDITIONS ARE EXPECTED. THE EXCEPTION WILL BE WITH ANY THUNDERSTORMS THAT DEVELOP WHICH ARE LIKELY TO AFFECT ALL OF TAF SITES LATER TODAY. THERE ARE TWO WINDOWS OF POTENTIAL TSRA. FIRST, A MESOSCALE CONVECTIVE COMPLEX SLIDING OUT OF WESTERN PA, COULD ARRIVE IN OUR AREA BY MID DAY. SECOND, STORMS COULD DEVELOP ALONG THE COLD FRONT THIS AFTERNOON. HOWEVER, IT SHOULD BE NOTED THAT TIMING OF THE FRONT IS STILL UNCERTAIN (ONE MODEL, THE NAM, IS AS MUCH AS 6 HOURS SLOWER THAN THE REST OF THE MODEL CONSENSUS). HAVE CHOSEN TO GO WITH TIMING SHOWN FOR THE GFS GUIDANCE, WHICH HAS BEEN THE MOST CONSISTENT RUN TO RUN. WITH ANY STORMS THAT DEVELOP, COULD SEE BRIEF IFR CONDITIONS AND VARIABLE AND GUSTY WINDS. FOR NOW WIND GUSTS TO 35KT WERE INCLUDED IN THE TAFS, BUT WIND GUSTS NEAR OR ABOVE 50 KT WILL BE POSSIBLE WITH THE STRONGEST STORMS. ONCE THE FRONT ARRIVES, SHOULD SEE CONDITIONS QUICKLY RETURN TO VFR, AND WILL ALSO SEE A WIND SHIFT TO NORTHWESTERLY. OUTLOOK... WED ...VFR. HIGH PRES. W TO NW WIND 10 TO 15 KT IN THE AFTN. HIGH CONFIDENCE. THU AND FRI...VFR CONDS ERLY THU THEN LOWERING CIGS BY LATER THU AND INTO THU NIGHT INTO FRI. MVFR AND IFR PSBL IF NOT LIKELY IN SHRA AND FG. GRADUALLY LOWERING TO MVFR WITH POSSIBLE IFR CONDS THURSDAY NIGHT IN SHOWERS/ST/FOG. SLY WIND SHIFT TO NE. LOW CONFIDENCE. SAT...E-NE GUSTS 20 KT. A SERIES OF LOW PRES SYS CUD IMPACT THE REGION OR REMAIN S. CONFIDENCE IS VERY LOW, BUT THERE COULD BE MVFR/IFR CONDS AND SHRA/FG FOR AT LEAST A PORTION OF SAT. && .MARINE... SOUTHWESTERLY WINDS NEAR 25KT WILL BUILD BY MID DAY, WITH SEAS BUILDING NEAR 5 FT IN RESPONSE. THUS SCA CONDITIONS ARE LIKELY FROM MID DAY INTO LATE AFTERNOON ON THE BAY, AND EARLY EVENING ON THE ATLANTIC WATERS (WHERE SEAS MAY BE A BIT SLOWER TO DECREASE. OUTLOOK... WED THRU FRI...LTST FCST HAS WIND AND SEAS REMAINING BELOW SCA CRITERIA. FRI NIGHT THRU SAT...SCA LIKELY. SEAS SHOULD BUILD TO 7 TO 8 FEET ON E TO NE FETCH. GUSTS AROUND 25 TO 30 KT AND PSBLY HIGHER. && .RIP CURRENTS... THERE IS A MODERATE RISK FOR RIP CURRENTS ALONG THE NEW JERSEY COAST AND LOW RISK FOR DELAWARE. IN HOUSE PROCEDURE WAS A MODERATE, WHILE GRIDDED CALCULATION WAS LOW. GIVEN THE WIND SCENARIO, THE MORNING MAY START WITH LOW RISKS EVERYWHERE AND THEN INCREASE TO MODERATE AS THE DAY PROGRESSES. && .CLIMATE... PHILADELPHIA HEAT WAVE CULMINATES WITH POSSIBLE NEAR RECORD WARMTH THIS AFTERNOON. TUESDAY JUNE 23 RECORDS: IN ALL PROBABILITY WILL REMAIN BELOW ALL VALUES LISTED BELOW, BUT COULD BE ESPECIALLY CLOSE AT KGED AND POSSIBLY OTHERS. KACY 98-1988 KILG 100-1894 KPHL 97-1888 KABE 95-1965 KTTN 97-1894 KRDG 96-1908 KMPO 90-1908 KGED 100-1988 && .PHI WATCHES/WARNINGS/ADVISORIES... PA...HEAT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR PAZ070-071-102-104-106. NJ...HEAT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR NJZ015-017>019. DE...HEAT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR DEZ001. MD...HEAT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR MDZ008. MARINE...SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 11 PM EDT THIS EVENING FOR ANZ450>455. SMALL CRAFT ADVISORY FROM 11 AM THIS MORNING TO 6 PM EDT THIS EVENING FOR ANZ430-431. && $$ SYNOPSIS...NIERENBERG NEAR TERM...JOHNSON SHORT TERM...JOHNSON LONG TERM...NIERENBERG AVIATION...JOHNSON/NIERENBERG MARINE...JOHNSON/NIERENBERG RIP CURRENTS...JOHNSON CLIMATE...
AREA FORECAST DISCUSSION
NWS JACKSONVILLE FL
1116 AM EDT TUE JUN 23 2015 .UPDATE...MAKING A SUBSTANTIAL UPDATE TO POP/WX/SKY GRIDS BASED ON CURRENT RADAR TRENDS AND LATEST HRRR. WIDESPREAD CLOUDS AND SHOWERS EXIST ACROSS SE GA. FOLLOWING LATEST HRRR TREND WITH DECREASING PRECIP COVERAGE EARLY THIS AFTERNOON ACROSS SE GA... AND INCREASING COVERAGE ACROSS NE FL WHERE FULL HEATING OCCURRING. MODEL GUIDANCE SHOWS DECENT MID-LEVEL VORT LOBE FROM COASTAL SE GA TO SUWANNEE VALLEY REGION OF NE FL FORECAST TO DRIFT SE. THIS FEATURE ALONG WITH SEA BREEZES SHOULD INITIATE SCATTERED TO NUMEROUS SHOWERS/T-STORMS WITH BETTER LATE AFTERNOON COVERAGE I-10 SOUTHWARD. KJAX VAD WIND PROFILE STILL SHOWING DECENT SW FLOW IN LOWEST GATES WHICH SHOULD LIMIT EAST COAST SEA BREEZE MOVEMENT TO JUST E OF I-95 CORRIDOR LATE IN THE DAY...WHILE WEST COAST SEA BREEZE PROGRESSES EASTWARD. CONSIDERABLE UNCERTAINTY AS TO HOW MUCH HEATING WILL OCCUR IN SE GA...WHEN IT COMES TO HIGH TEMP FORECAST. LOWERED HIGH TEMP FORECAST TO LOW 90S FOR NOW...WILL ONLY TAKE A FEW LATE AFTERNOON HOURS OF HEATING TO REACH THAT. && .PRELIMINARY POINT TEMPS/POPS... AMG 92 75 97 75 / 70 40 40 30 SSI 92 79 91 78 / 30 30 30 20 JAX 96 75 95 76 / 50 50 40 20 SGJ 92 76 90 76 / 40 40 30 20 GNV 96 74 94 74 / 60 60 50 20 OCF 95 74 94 75 / 60 60 40 20 && .JAX WATCHES/WARNINGS/ADVISORIES... FL...NONE. GA...NONE. AM...NONE. && $$ WOLF//
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1000 AM EDT TUE JUN 23 2015 .UPDATE...SFC HIGH PRES RIDGE HAS EXPANDED/LIFTED NWD SOME COMPARED TO YDAY`S POSN NEAR VRB-ZPH...AND NOW LIES NEAR MLB-BKV...WITH A BIT LESS CURVATURE ABOUT ITS AXIS. MID/UPPER LEVEL RIDGE REMAINS IN PLACE OVHD WITH A NARROW COL STARTING TO DEVELOP NEAR A TPA-SAV-CHS LINE. VISIBLE SATELLITE IMAGERY SHOWS CONSIDERABLE EARLY MORNING UPPER DEBRIS CLOUDS ADVECTING IN FROM THE NNE-NE STARTING TO THIN ATTM. CONSIDERABLE MOISTENING SHOWS UP IN THE 12Z XMR RAOB...NEARLY 2.0" MEAN PWAT COMPARED TO THE PRONOUNCED DRYING WHICH OCCURRED BTWN 12Z MON AND 00Z TUE (1.8" --> 1.4"). WITH THE LCL AIR MASS MUCH MORE MOIST THAN THE PAST COUPLE DAYS...IT FOLLOWS THAT LCL SEA BREEZE BDRYS SHOULD BE MORE CONVECTIVELY ACTIVE IN AND OF THEMSELVES...RATHER THAN NEEDING A COLLISION TO GENERATE ANY CONVECTION OF SIGNIFICANT STRENGTH. INDEED THE LAST FEW RUNS OF THE HRRR SHOW THIS TAKING PLACE...CONSEQUENTLY POPS ALONG THE COAST ARE 30-40 RATHER THAN 20...WITH 50 ACROSS THE SOUTHERN HALF OF THE INTERIOR. THERE WAS SOME EARLIER CONCERN THAT DEBRIS CLOUDS COULD INHIBIT SFC HEATING BY A COUPLE DEGREES AND RESULTANT INSTABILITY TO A SMALL DEGREE EARLY ON BUT WITH CLOUDS THINNING...DON`T THINK THIS WILL WIND UP BEING THAT MUCH OF A FACTOR. OTHER THAN SOME MINOR TWEAKS TO TEMPS AND SKY COVER...FCST WILL REMAIN LARGELY UNCHANGED. && .AVIATION...BEST CHC FOR TS AT COASTAL AERODROMES WILL BE 16Z-20Z WITH ACTIVITY IMPACTING THE INLAND SITES MAINLY FROM 21Z-02Z OR SO. A LITTLE POTENTIAL FOR IMC/WIND GUSTS 30KT+ ESPECIALLY INLAND...GIVEN EXPECTED HIGHER COVERAGE. && .MARINE...ANOTHER DAY HAS DAWNED AND 3FT SEAS HAVE YET TO SHOW UP... YET AGAIN. THIS REMAINS A BIT OF A QUIBBLE SINCE BOATING CONDS ARE QUITE BENIGN...BUT I CAN`T REMEMBER BOTH THE WNAWAVE/NWPS HAVING A 1-2FT HIGH BIAS FOR SO MANY CYCLES IN A ROW IN SOME TIME. WHILE WE MAY SEE 3FT SEAS LEAK INTO THE OUTER WATERS PLAN TO ONCE AGAIN PARE BACK SEAS TO 1-2FT NEAR SHORE AND AROUND 2FT OFFSHORE...UNTIL SEAS SHOW A SIGN OF NUDGING AT LEAST 2.5FT AT 41009/41010. && FORECAST/UPDATE...CRISTALDI AVIATION/RADAR/IMPACT WX...SEDLOCK && .PREV DISCUSSION... /ISSUED 430 AM EDT TUE JUN 23 2015/ ...SCATTERED SHOWERS/STORMS EXPECTED INTO THE UPCOMING WEEKEND... WED-WED NIGHT... ZONAL H30-H20 JET OVER THE NRN TIER STATES WILL PUSH A STORM SYSTEM FROM THE GREAT LAKES INTO ERN CANADA. SRN EXTENSION OF ITS TRAILING TROF AXIS WILL WORK ITS WAY INTO A WEAKNESS IN THE H100-H70 ATLC RIDGE OVER GA/FL. THIS WILL EFFECTIVELY SPLIT THE RIDGE IN TWO WITH ITS WRN PORTION BCMG AN INDEPENDENT ANTICYCLONE CENTERED NEAR THE ARKLATEX WHILE ITS MAIN BODY RETREATS E OF THE BAHAMA BANK. THE RESULTING COL WILL COLLAPSE THE DEEP LYR FLOW OVER THE FL PENINSULA. WITH SUCH WEAK FLOW IN PLACE...ANY STORMS THAT DEVELOP WILL BE SLOW MOVERS AT BEST. MODERATE MID LVL INSTABILITY WILL COME FROM A BAND OF ENHANCED VORTICITY OVER THE FL PANHANDLE THAT WILL WORK ITS WAY SWD WITH THE APPROACHING TROF. H30-H20 ANTICYCLONE OVER N FL WILL PRODUCE WEAK UPR LVL EVACUATION...BUT ALSO WILL ALLOW SIG CONVECTIVE DEBRIS CLOUDS TO REMAIN TRAPPED OVER THE FL PENINSULA. INDEED...WHILE MODEL SOUNDINGS INDICATE PWAT VALUES RECOVERING TO ARND 2.0"...MUCH OF IT IS TRAPPED IN AN H40-H20 SATURATION LYR. STAGE IS SET FOR ANOTHER DAY OF PULSE CONVECTION. H70/H50 RUNNING 8C/-8C RESPECTIVELY...YIELDING RESPECTABLE LAPSE RATE OF 6.0-6.5C/KM THRU THE LYR. MODEL SOUNDINGS TO INDICATE A FAIR AMOUNT OF DRY AIR THRU THE H85-H50 LYRS...RAISING THE POTENTIAL FOR STRONG TO SEVERE DOWNBURST WINDS. DEBRIS CLOUDS MAY HAMPER SFC HEATING SOMEWHAT...AND WEAK STEERING FLOW WILL KEEP THE EAST/WEST COAST SEA BREEZES FROM MAKING RAPID INLAND PROGRESS. GFS MOS POPS APPEAR A LITTLE HIGH GIVEN THESE INHIBITORS...BUT FOCUS FOR DIURNAL CONVECTION WILL BE OVER THE INTERIOR COUNTIES. MAX TEMPS AGAIN IN THE L/M90S AS THE STATIC AIR MASS OVERHEAD WILL HEAT UP QUITE EFFICIENTLY...MIN TEMPS IN THE L/M70S...NEAR THEIR RESPECTIVE DEWPOINTS. THU-THU NIGHT... TROF OVER THE ERN SEABOARD WILL DAMPEN OUT AS ITS PARENT LOW MOVES INTO THE CANADIAN MARITIMES. ATLC RIDGE AXIS WILL REBUILD ITSELF OVER THE FL PENINSULA...RESULTING IN SLIGHTLY STRONGER E/SERLY FLOW THRU THE H100-H50 LYR. FOCUS FOR DIURNAL PRECIP WILL SHIFT BACK TO THE W FL PENINSULA WITH LOW PROSPECT FOR RAINFALL ALONG THE ERN COASTAL COUNTIES. CONTINUED HOT WITH MAX TEMPS IN THE L/M90S...MINS L/M70S. FRI-MON... PATTERN CHANGE IN THE NRN JET AS IT SHIFT FROM A ZONAL TO MORE MERIDIONAL ORIENTATION OVER THE ERN CONUS...DEVELOPING A HI AMP MID/UPR LVL SHORT WAVE IN THE PROCESS. BOTH GFS/ECMWF MODELS RESPOND BY DVLPG A LARGE AREA OF LOW PRES OVER THE MID AND DEEP SOUTH THAT WILL SUPPRESS THE ATLC RIDGE AXIS INTO S FL THRU EARLY NEXT WEEK. THE RESULTING H100-H70 FLOW WILL SHIFT TO THE S ON FRI...THEN TO THE SW ON SAT...RESULTING IN HIGHER DIURNAL POPS OVER THE E FL COAST. HOWEVER...NEITHER MODEL IS PARTICULARLY GUNG-HO WITH POPS AS BOTH INDICATE LOW RH AIR OVER THE WRN CARIB WORKING ITS WAY NWD AND BCMG ENTRAINED IN THE DVLPG SWRLY FLOW. PRECIP CHANCES GENERALLY AOB 50PCT WITH TEMPS RETURNING NEAR OR SLIGHTLY ABV AVG...MAXES U80SL90S AND MINS L/M70S. && .AVIATION...SHOULD SEE EARLIER START TO CONVECTIVE DEVELOPMENT TODAY INITIALLY ALONG THE SEA BREEZE FROM KSUA-KMLB...AND THEN SCATTERED STORMS DEVELOPING NORTHWARD TOWARD INTERIOR TERMINALS IN THE MID TO LATE AFTERNOON. ISOLD TSRA MAY LINGER INTO THE EVENING PAST 01Z...MAINLY NORTH OF A KISM-KTIX LINE BUT PROBS TOO LOW TO MENTION. && .MARINE... SEAS REMAIN RATHER FLAT AT 1-2 FT NEAR SHORE AND 2 FT AT BUOY 41009 EARLY THIS MORNING. S/SSW WINDS THIS MORNING WILL VEER TO THE SE THIS AFTERNOON TO AROUND 10 KNOTS...THEN WINDS FROM THE SE/S WILL BECOME SSW/SW TONIGHT. WILL KEEP SEAS AROUND 2 FT NEAR SHORE AND PERHAPS UP TO 2-3 FT FOR THE NRN OFFSHORE WATERS LATE TONIGHT. WED-SAT...GENERALLY FAVORABLE BOATING CONDITIONS AS THE ATLC RIDGE AXIS MEANDERS BTWN THE CENTRAL AND SRN FL PENINSULA WHILE A SERIES OF LOW PRESSURE SYSTEMS WORK THEIR WAY ACRS THE ERN CONUS. GENTLE TO MODERATE S/SW BREEZE THRU THE END OF THE WEEK...SEAS 2-3FT. INCREASING CHANCES FOR OFFSHORE MOVING TSRAS IN THE AFTN/EVNG AS THE WEEKEND APPROACHES. && .CLIMATE... DAYTONA BEACH TIED THEIR RECORD HIGH OF 96 DEGREES YESTERDAY SET BACK IN 2009. RECORD HIGHS TODAY LOOK OUT OF REACH: RECORDS HIGHS FOR TODAY/JUNE 23RD... DAYTONA BEACH 100 IN 1944 ORLANDO 99 IN 1939 MELBOURNE 96 IN 1998 VERO BEACH 94 IN 2009 HIGH MINIMUM TEMPERATURES RECORDS TODAY WHICH COULD BE TIED OR BROKEN. DAYTONA BEACH 77 IN 1972 VERO BEACH 79 IN 2010 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
755 AM EDT TUE JUN 23 2015 .SYNOPSIS... ABOVE NORMAL TEMPERATURES WILL CONTINUE ACROSS THE REGION THIS WEEK AS THE SUBTROPICAL RIDGE HOLDS ACROSS THE SOUTHERN STATES. THE CHANCE FOR AFTERNOON AND EVENING THUNDERSTORMS SHOULD INCREASE FOR THE WEEKEND AS AN UPPER LEVEL TROUGH BUILDS ACROSS THE EASTERN CONUS. && .NEAR TERM /THROUGH TONIGHT/... MODELS INDICATE A WEAKNESS IN THE UPPER RIDGE STRETCHING ACROSS THE SOUTHERN TIER STATES TODAY AS AN UPPER TROUGH CROSSES THE GREAT LAKES REGION AND NORTHEASTERN STATES. A WEAK SHORTWAVE ACROSS THE UPSTATE THIS MORNING IS ALSO PROGGED TO CROSS THE MIDLANDS THIS AFTERNOON AND EVENING. THE GFS AND ECMWF TRACK THE SHORT WAVE EAST OF THE MIDLANDS AND CSRA BY MID AFTERNOON WHILE THE NAM...RAP AND HRRR MODELS ARE SLOWER. A LEE TROUGH WILL FROM THE MID-ATLANTIC STATES INTO PIEDMONT. STRONG DIABATIC HEATING AND A MOIST AIRMASS WITH PWAT AROUND 1.50 TO 2.00 INCHES WILL CONTRIBUTE TO STEEP 0-3 KM LAPSE RATES AND MODERATE TO STRONG BUOYANCY DEVELOPING AS TEMPS WARM INTO THE 90S. WILL CONTINUE TO INDICATE SCATTERED AFTERNOON/EVENING CONVECTION WITH SLIGHT CHANCE POPS WEST INCREASING TO ABOUT 40 PERCENT EAST. WATER-LOADED DOWNDRAFTS COULD RESULT IN WET MICROBURSTS CAPABLE OF 45-60 MPH WIND GUSTS AND POCKETS OF WIND DAMAGE BEFORE THIS ACTIVITY DIMINISHES DURING THE EARLY EVENING. ONCE AGAIN EXPECT AFTERNOON HIGHS IN THE UPPER 90S TO AROUND 100 DEGREES WITH LOWS TONIGHT IN THE MID 70S. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... THE MAIN UPPER RIDGE CENTER OVER TN/AR WILL BEGIN BUILDING INTO THE CAROLINAS AND GEORGIA WEDNESDAY. A WEAK BACKDOOR COLD FRONT IS FORECAST TO SAG NEAR THE SC/NC BORDER WEDNESDAY. CONVERGENCE ALONG THE FRONT COMBINED WITH A MOIST AND MODERATE TO STRONG INSTABILITY WILL KEEP A CHANCE OF THUNDERSTORMS ACROSS THE REGION. KEPT POPS AROUND 30 PERCENT ON WEDNESDAY AND NEAR 40 PERCENT THURSDAY. . TEMPERATURES WILL CONTINUE THE DAILY TREK TOWARDS THE CENTURY MARK EACH AFTERNOON...WITH OVERNIGHT LOWS ONLY FALLING INTO THE MIDDLE TO UPPER 70S. AFTERNOON HEAT INDEX VALUES RANGE GENERALLY FROM 104 TO 108 EACH DAY. && .LONG TERM /FRIDAY THROUGH MONDAY/... SOME RELIEF FROM THE HEAT SHOULD BE ON THE WAY FOR THE WEEKEND. BY FRIDAY THE MODELS BEGIN TO MOVE THE CENTER OF THE UPPER RIDGE FURTHER OFF TO THE WEST...WHICH WILL THEN AID IN THE DEVELOPMENT OF TROUGHING ALONG THE EASTERN UNITED STATES. BOTH THE GFS AND THE ECMWF ARE IN AGREEMENT WITH THIS PATTERN SHIFT THROUGH THE PERIOD...WITH A RATHER DEEP TROUGH SETTING UP. THIS SHOULD BE A WELCOMED CHANGE TO THE REGION. HIGH TEMPERATURES WILL COOL SLIGHTLY INTO THE LOWER/MIDDLE 90S FOR FRIDAY AND SATURDAY...AND THEN MAYBE JUST AROUND 90 SUNDAY AND MONDAY. WITH THE DEVELOPMENT OF THE UPPER TROUGH...THE REGION SHOULD SEE A BETTER SOUTHWARD PUSH TO ANY COLD FRONTS PUSHING INTO THE REGION. THIS SHOULD HELP WITH AN INCREASE IN THE RAIN CHANCES INTO AND THROUGH THE WEEKEND...WITH COVERAGE BECOMING MORE SCATTERED ACROSS THE REGION. THE CONVECTION SHOULD REMAIN MAINLY BE DIURNALLY INDUCED. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... VFR CONDITIONS EXPECTED FOR MOST OF THE PERIOD...WITH POTENTIAL FOR AFTERNOON AND EVENING CONVECTION. AREA REMAINS UNDER UPPER LEVEL RIDGING WITH SATELLITE IMAGERY SHOWING SOME MID LEVEL CLOUDS ACROSS THE SOUTHERN MIDLANDS AND CSRA. CUMULUS WILL AGAIN DEVELOP DURING THE LATE MORNING AND AFTERNOON HOURS WITH CONVECTION POSSIBLE THIS AFTERNOON AND EVENING. BEST CHANCE OF CONVECTION WILL BE AT OGB AND HAVE INCLUDED VCTS BETWEEN 20Z AND 24/01Z. THUNDERSTORMS WHICH DEVELOP WILL HAVE THE POTENTIAL TO PRODUCE STRONG AND GUSTY WINDS. CONVECTION WILL DIMINISH WITH SUNSET WITH REMAINDER OF THE PERIOD EXPECTED VFR. WINDS THROUGH THE PERIOD WILL BE SOUTHWESTERLY AT 10 KNOTS OR LESS. EXTENDED AVIATION OUTLOOK...BRIEF RESTRICTIONS POSSIBLE IN MAINLY AFTERNOON AND EVENING CONVECTION AS THUNDERSTORM CHANCES INCREASE EACH DAY THROUGH SATURDAY. && .CLIMATE... RECORDS FROM TUE JUNE 23RD THROUGH THU JUNE 25TH AUGUSTA... JUN 23...104 IN 1944 JUN 24...103 IN 1914 JUN 25...104 IN 1914 COLUMBIA... JUN 23...102 SET IN 1914 AND TIED IN 1956 AND 1988 JUN 24...103 IN 1914 JUN 25...103 IN 1952 && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$ 99
AREA FORECAST DISCUSSION
NWS JACKSON KY
1043 AM EDT TUE JUN 23 2015 .UPDATE... ISSUED AT 1041 AM EDT TUE JUN 23 2015 BASED ON THE LATEST HRRR...WHICH IS INITIALIZING VERY WELL SO FAR THIS MORNING...AS WELL AS SUPPORT FROM OTHER HI RES MODELS...WENT AHEAD AND UPDATED POPS FOR THE REMAINDER OF THE DAY. WHILE THIS DIDN/T CREATE ANY DRASTIC CHANGES...DO EXPECT OUR BEST CHANCES FOR STORMS AND SCATTERED COVERAGE TO BE CONTAINED ALONG AND THEN SOUTH OF THE OHIO RIVER THIS AFTERNOON AND INTO THIS EVENING. THIS LED TO A SLIGHT REDUCTION IN POPS THIS MORNING IN THE NORTH...REDUCING THEM DOWN TO ISOLATED...BECOMING SCATTERED ONCE STORMS DROP BELOW THE OHIO RIVER AREA. ALSO LOADED IN THE LATEST OBSERVATIONAL DATA TO MAKE SURE THE CURRENT TEMPS...DEW POINTS...AND WINDS WERE WELL REFLECTED IN THE NEAR TERM CONDITIONS. UPDATE ISSUED AT 735 AM EDT TUE JUN 23 2015 WHILE A FEW SHOWERS DID POP UP OVER TENNESSEE...NOTHING ELSE HAS BEEN NOTED WITH THE INITIAL BOUNDARY CROSSING EASTERN KENTUCKY THIS MORNING. THUS...WILL REMOVE RAIN CHANCES THIS MORNING IN FAVOR OF RAIN CHANCES WITH THE COLD FRONT THIS AFTERNOON/EVENING. HRRR/RAP CONTINUES TO SHOW SOME SCATTERED CONVECTION DEVELOPING AND APPEARS TO MOVE SOUTH MUCH FASTER THAN THE NAM. IN FACT...IF THE HI RES MODELS WORK OUT...VERY LITTLE PRECIPITATION WILL BE POSSIBLE AFTER 00Z THIS EVENING. THE LAST FEW RUNS OF THE HI RES MODELS ALSO SHOW VARYING DEGREES OF COVERAGE AND IN SOME CASES VERY LOW COVERAGE...SO ITS STILL POSSIBLE SOME AREAS WILL STAY DRY THROUGH THE DAY DESPITE THE COLD FRONTAL PASSAGE. NO CHANGES TO SEVERE THREATS AS DAMAGING WINDS WILL REMAIN POSSIBLE WITH THE STRONGEST STORMS TODAY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 A COUPLE OF BOUNDARIES TO KEEP AN EYE ON TODAY. THE FIRST ONE IS CROSSING INTO CENTRAL KENTUCKY PRESENTLY AND HAS BEEN VISIBLE ON AREA RADARS. THE SECOND BOUNDARY WILL BE A COLD FRONT ACROSS THE LOWER GREAT LAKES THAT WILL SWEEP SOUTH ACROSS THE AREA LATER TODAY. IN THE IMMEDIATE SHORT TERM...FOCUS IS ON THE FIRST BOUNDARY. HRRR CONTINUES TO SHOW SOME DEVELOPMENT ALONG THE BOUNDARY POSSIBLE AS IT SHIFTS EAST ACROSS THE AREA THROUGH DAYBREAK. NOT MUCH NOTED SO FAR...AND THE RAP HAS BACKED OFF ON THE POSSIBLE CONVECTION. WILL MAINTAIN SOME SLIGHT CHANCE POPS AS THIS BOUNDARY PROGRESSES ACROSS THE AREA THIS MORNING. IT LOOKS LIKE A LULL IS EXPECTED THROUGH MUCH OF THE COMING DAY AS WE WAIT FOR THE COLD FRONT TO THE NORTH TO DROP SOUTH. THIS SHOULD HAPPEN BY 2 PM WITH CHANCES OF SHOWERS AND STORMS MOVING INTO THE I-64 CORRIDOR. THE CHANCES WILL SPREAD SOUTH THROUGH THE REMAINDER OF THE AFTERNOON/EVENING. STILL HESITANT TO GO UP TO LIKELY POPS GIVEN THE MAIN FORCING IS EXPECTED TO STAY TO OUR NORTHEAST...BUT GIVEN THE BOUNDARY...WE SHOULD AT LEAST SEE SOME SCATTERED COVERAGE OF SHOWERS/STORMS...ESPECIALLY GIVEN THE INSTABILITY DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON. BETTER SHEAR IS OFF TO OUR NORTHEAST WHERE THERE IS AN ENHANCED AREA FOR SEVERE THUNDERSTORMS. HOWEVER...WITH MARGINAL SHEAR OVER THE AREA...A FEW STORMS COULD PRODUCE A SEVERE WIND GUST. HAIL THREAT IS PRETTY LOW WITH FREEZING LEVELS AT OR ABOVE 15KFT. OVERALL...SEVERE THREAT IS NOT LOOKING ALL THAT GREAT...BUT JUST GOOD ENOUGH FOR THE SEVERE STORM PREDICTION CENTER TO MAINTAIN THE SLIGHT CHANCE OF SEVERE STORMS OVER EASTERN KENTUCKY. WILL CONTINUE TO HIGHLIGHT DAMAGING WINDS AS THE MAIN THREAT. FRONTAL BOUNDARY LOOKS TO DIVE A BIT FARTHER SOUTH TONIGHT...WHICH WILL TAKE THE CONVECTION TO THE SOUTH. ANY POSSIBLE MCS DEVELOPING UPSTREAM WILL ALSO STAY SOUTH GIVEN THE FRONTAL PLACEMENT. THIS SHOULD SPELL A DRY NIGHT. HOWEVER...WITH COOLER AIR FILTERING IN FROM THE NORTH AND SURFACE MOISTURE LIKELY LAGGING BEHIND THE FRONT...WE MAY SEE SOME DENSE FOG DEVELOP TONIGHT. GUIDANCE IS HITTING THE FOG FAIRLY HARD...AND SEE NO REASON TO NOT DO THE SAME. THUS...WILL MENTION WIDESPREAD DENSE FOG IN THE VALLEYS WITH MORE PATCHY ON THE RIDGES. THE BLUEGRASS REGION MAY MAINTAIN ENOUGH WIND TO LIMIT THE FOG POTENTIAL OUT THAT WAY. WEDNESDAY IS LOOKING MORE LIKE A DRY DAY AS THE FRONT SETTLES WELL TO OUR SOUTH. WE COULD POP OFF A SHOWER OR STORM IN SOUTHEAST KENTUCKY...BUT GUIDANCE HAS REALLY CUT BACK ON POPS FOR MOST OF THE AREA. THUS...WILL GO TOWARDS A DRIER SOLUTION FOR THE DAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 340 AM EDT TUE JUN 23 2015 A CHANGE TO THE OVERALL PATTERN IS ON THE HORIZON IN THE LONG TERM PERIOD. THE PERIOD WILL BEGIN WITH UPPER LEVEL HIGH STILL GENERALLY CENTERED ACROSS THE SE US WITH BEST JET ENERGY ACROSS THE GREAT LAKES AND SOUTHERN NEW ENGLAND. MODELS ARE IN GOOD AGREEMENT WITH THE RIDGE BREAKING DOWN AS WE MOVE TOWARD FRIDAY TIME FRAME WITH UPPER LEVEL HIGH SHIFTING ACROSS THE WESTERN US. THIS WILL INTRODUCE HEIGHT FALLS ACROSS THE EASTERN US AS TROUGH IS EXPECTED TO CONTINUE TO AMPLIFY/CUTOFF ACROSS THE EASTERN GREAT LAKES. HOWEVER RIGHT NOW THE GFS/CANADIAN/GFS ENSEMBLE ARE MOST AMPLIFIED COMPARED TO THE ECMWF WITH SUB 576 HEIGHTS MAKING IT INTO THE OHIO VALLEY. WEAK SURFACE HIGH WILL BE OFF TO THE NORTH AND WARM FRONT SOUTH OF THE REGION ON WEDNESDAY NIGHT TO BEGIN THE LONG TERM PERIOD. THIS WILL BE SHORT LIVED WITH ACTIVE PATTERN AND TROUGHING SETTING UP ACROSS THE EASTERN US. THE FRONT WILL MEANDER AROUND THE REGION THROUGH THE PERIOD WITH SEVERAL AREAS OF LOW PRESSURE DEVELOPING. THIS BOUNDARY WILL BE THE FOCUS OF CONVECTION THROUGH THE PERIOD AND WILL GIVE WAY TO MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS THURSDAY INTO SATURDAY. A FRONTAL BOUNDARY NEAR THE REGION...UPPER 60S TO LOW 70 DEWPOINTS...CAPES AOA 2000 J/KG...DCAPES NEARING 1000 J/KG...AND BULK SHEAR NEARING 30 KNOTS WITH LOWERING HEIGHTS WILL LEAD TO STRONG TO EVEN POTENTIAL FOR SEVERE STORMS THURSDAY INTO FRIDAY. THE MAIN THREAT LOOKS TO BE STRONG WINDS AND HEAVY RAIN WITH ONLY MARGINAL HAIL POTENTIAL GIVEN HIGHER FREEZING LEVELS AROUND 13 TO 14 KFT. RAIN THREAT WILL SUBSIDE AS WE MOVE LATE INTO THE WEEKEND...AS LOW PRESSURE SYSTEM AND BOUNDARY MOVE SOUTH AND EAST OF THE REGION WITH HIGH PRESSURE MOVING EAST. THIS WILL USHER IN COOLER AND DRYER CONDITIONS AS WE MOVE INTO THE SUNDAY TIME FRAME. HOWEVER UNDER NW FLOW ALOFT AND UPPER LEVEL TROUGH PASSING OVER COULD LEAD TO STRATUS DECK HANGING ON. THIS STRATUS IS SUGGESTED BY THE GFS FORECAST SOUNDINGS AND ECMWF TIME HEIGHTS. RIGHT NOW CONFIDENCE FOR MONDAY IS LOWER BUT DID OPT TO KEEP SOME SLIGHT POPS AT THIS POINT. TEMPERATURES WILL BEGIN ABOVE NORMAL FOR THIS TIME OF YEAR ON THURSDAY. TEMPERATURE FRIDAY BEGIN TO SHIFT TO AT OR NEAR NORMAL BEFORE A BELOW NORMAL SHIFT WITH HIGHS ON POTENTIALLY STAYING IN THE LOW TO MID 70S SUNDAY. THIS WOULD BE 10 OR MORE DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 735 AM EDT TUE JUN 23 2015 VFR CONDITIONS WILL PREVAIL THROUGH THIS EVENING. SOME THUNDERSTORMS MAY DEVELOP ALONG AN APPROACHING COLD FRONT LATER THIS AFTERNOON AND EVENING. COVERAGE IS STILL UNCERTAIN AT THIS TIME...BUT WILL KEEP VCTS TO PROVIDE A WINDOW OF OPPORTUNITY FOR CONVECTION. AS THE FRONT PASSES THIS EVENING...COOLER AIR WILL FILTER INTO THE REGION...BUT MOISTURE MAY LINGER A BIT LONGER WHICH COULD SET THE STAGE FOR SOME DENSE FOG TONIGHT. THIS WILL HAVE THE POTENTIAL TO DROP CIGS OR VISIBILITIES BELOW AIRPORT MINIMUMS LATE TONIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...KAS LONG TERM...DJ AVIATION...KAS
AREA FORECAST DISCUSSION
NWS JACKSON KY
735 AM EDT TUE JUN 23 2015 .UPDATE... ISSUED AT 735 AM EDT TUE JUN 23 2015 WHILE A FEW SHOWERS DID POP UP OVER TENNESSEE...NOTHING ELSE HAS BEEN NOTED WITH THE INITIAL BOUNDARY CROSSING EASTERN KENTUCKY THIS MORNING. THUS...WILL REMOVE RAIN CHANCES THIS MORNING IN FAVOR OF RAIN CHANCES WITH THE COLD FRONT THIS AFTERNOON/EVENING. HRRR/RAP CONTINUES TO SHOW SOME SCATTERED CONVECTION DEVELOPING AND APPEARS TO MOVE SOUTH MUCH FASTER THAN THE NAM. IN FACT...IF THE HI RES MODELS WORK OUT...VERY LITTLE PRECIPITATION WILL BE POSSIBLE AFTER 00Z THIS EVENING. THE LAST FEW RUNS OF THE HI RES MODELS ALSO SHOW VARYING DEGREES OF COVERAGE AND IN SOME CASES VERY LOW COVERAGE...SO ITS STILL POSSIBLE SOME AREAS WILL STAY DRY THROUGH THE DAY DESPITE THE COLD FRONTAL PASSAGE. NO CHANGES TO SEVERE THREATS AS DAMAGING WINDS WILL REMAIN POSSIBLE WITH THE STRONGEST STORMS TODAY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 A COUPLE OF BOUNDARIES TO KEEP AN EYE ON TODAY. THE FIRST ONE IS CROSSING INTO CENTRAL KENTUCKY PRESENTLY AND HAS BEEN VISIBLE ON AREA RADARS. THE SECOND BOUNDARY WILL BE A COLD FRONT ACROSS THE LOWER GREAT LAKES THAT WILL SWEEP SOUTH ACROSS THE AREA LATER TODAY. IN THE IMMEDIATE SHORT TERM...FOCUS IS ON THE FIRST BOUNDARY. HRRR CONTINUES TO SHOW SOME DEVELOPMENT ALONG THE BOUNDARY POSSIBLE AS IT SHIFTS EAST ACROSS THE AREA THROUGH DAYBREAK. NOT MUCH NOTED SO FAR...AND THE RAP HAS BACKED OFF ON THE POSSIBLE CONVECTION. WILL MAINTAIN SOME SLIGHT CHANCE POPS AS THIS BOUNDARY PROGRESSES ACROSS THE AREA THIS MORNING. IT LOOKS LIKE A LULL IS EXPECTED THROUGH MUCH OF THE COMING DAY AS WE WAIT FOR THE COLD FRONT TO THE NORTH TO DROP SOUTH. THIS SHOULD HAPPEN BY 2 PM WITH CHANCES OF SHOWERS AND STORMS MOVING INTO THE I-64 CORRIDOR. THE CHANCES WILL SPREAD SOUTH THROUGH THE REMAINDER OF THE AFTERNOON/EVENING. STILL HESITANT TO GO UP TO LIKELY POPS GIVEN THE MAIN FORCING IS EXPECTED TO STAY TO OUR NORTHEAST...BUT GIVEN THE BOUNDARY...WE SHOULD AT LEAST SEE SOME SCATTERED COVERAGE OF SHOWERS/STORMS...ESPECIALLY GIVEN THE INSTABILITY DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON. BETTER SHEAR IS OFF TO OUR NORTHEAST WHERE THERE IS AN ENHANCED AREA FOR SEVERE THUNDERSTORMS. HOWEVER...WITH MARGINAL SHEAR OVER THE AREA...A FEW STORMS COULD PRODUCE A SEVERE WIND GUST. HAIL THREAT IS PRETTY LOW WITH FREEZING LEVELS AT OR ABOVE 15KFT. OVERALL...SEVERE THREAT IS NOT LOOKING ALL THAT GREAT...BUT JUST GOOD ENOUGH FOR THE SEVERE STORM PREDICTION CENTER TO MAINTAIN THE SLIGHT CHANCE OF SEVERE STORMS OVER EASTERN KENTUCKY. WILL CONTINUE TO HIGHLIGHT DAMAGING WINDS AS THE MAIN THREAT. FRONTAL BOUNDARY LOOKS TO DIVE A BIT FARTHER SOUTH TONIGHT...WHICH WILL TAKE THE CONVECTION TO THE SOUTH. ANY POSSIBLE MCS DEVELOPING UPSTREAM WILL ALSO STAY SOUTH GIVEN THE FRONTAL PLACEMENT. THIS SHOULD SPELL A DRY NIGHT. HOWEVER...WITH COOLER AIR FILTERING IN FROM THE NORTH AND SURFACE MOISTURE LIKELY LAGGING BEHIND THE FRONT...WE MAY SEE SOME DENSE FOG DEVELOP TONIGHT. GUIDANCE IS HITTING THE FOG FAIRLY HARD...AND SEE NO REASON TO NOT DO THE SAME. THUS...WILL MENTION WIDESPREAD DENSE FOG IN THE VALLEYS WITH MORE PATCHY ON THE RIDGES. THE BLUEGRASS REGION MAY MAINTAIN ENOUGH WIND TO LIMIT THE FOG POTENTIAL OUT THAT WAY. WEDNESDAY IS LOOKING MORE LIKE A DRY DAY AS THE FRONT SETTLES WELL TO OUR SOUTH. WE COULD POP OFF A SHOWER OR STORM IN SOUTHEAST KENTUCKY...BUT GUIDANCE HAS REALLY CUT BACK ON POPS FOR MOST OF THE AREA. THUS...WILL GO TOWARDS A DRIER SOLUTION FOR THE DAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 340 AM EDT TUE JUN 23 2015 A CHANGE TO THE OVERALL PATTERN IS ON THE HORIZON IN THE LONG TERM PERIOD. THE PERIOD WILL BEGIN WITH UPPER LEVEL HIGH STILL GENERALLY CENTERED ACROSS THE SE US WITH BEST JET ENERGY ACROSS THE GREAT LAKES AND SOUTHERN NEW ENGLAND. MODELS ARE IN GOOD AGREEMENT WITH THE RIDGE BREAKING DOWN AS WE MOVE TOWARD FRIDAY TIME FRAME WITH UPPER LEVEL HIGH SHIFTING ACROSS THE WESTERN US. THIS WILL INTRODUCE HEIGHT FALLS ACROSS THE EASTERN US AS TROUGH IS EXPECTED TO CONTINUE TO AMPLIFY/CUTOFF ACROSS THE EASTERN GREAT LAKES. HOWEVER RIGHT NOW THE GFS/CANADIAN/GFS ENSEMBLE ARE MOST AMPLIFIED COMPARED TO THE ECMWF WITH SUB 576 HEIGHTS MAKING IT INTO THE OHIO VALLEY. WEAK SURFACE HIGH WILL BE OFF TO THE NORTH AND WARM FRONT SOUTH OF THE REGION ON WEDNESDAY NIGHT TO BEGIN THE LONG TERM PERIOD. THIS WILL BE SHORT LIVED WITH ACTIVE PATTERN AND TROUGHING SETTING UP ACROSS THE EASTERN US. THE FRONT WILL MEANDER AROUND THE REGION THROUGH THE PERIOD WITH SEVERAL AREAS OF LOW PRESSURE DEVELOPING. THIS BOUNDARY WILL BE THE FOCUS OF CONVECTION THROUGH THE PERIOD AND WILL GIVE WAY TO MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS THURSDAY INTO SATURDAY. A FRONTAL BOUNDARY NEAR THE REGION...UPPER 60S TO LOW 70 DEWPOINTS...CAPES AOA 2000 J/KG...DCAPES NEARING 1000 J/KG...AND BULK SHEAR NEARING 30 KNOTS WITH LOWERING HEIGHTS WILL LEAD TO STRONG TO EVEN POTENTIAL FOR SEVERE STORMS THURSDAY INTO FRIDAY. THE MAIN THREAT LOOKS TO BE STRONG WINDS AND HEAVY RAIN WITH ONLY MARGINAL HAIL POTENTIAL GIVEN HIGHER FREEZING LEVELS AROUND 13 TO 14 KFT. RAIN THREAT WILL SUBSIDE AS WE MOVE LATE INTO THE WEEKEND...AS LOW PRESSURE SYSTEM AND BOUNDARY MOVE SOUTH AND EAST OF THE REGION WITH HIGH PRESSURE MOVING EAST. THIS WILL USHER IN COOLER AND DRYER CONDITIONS AS WE MOVE INTO THE SUNDAY TIME FRAME. HOWEVER UNDER NW FLOW ALOFT AND UPPER LEVEL TROUGH PASSING OVER COULD LEAD TO STRATUS DECK HANGING ON. THIS STRATUS IS SUGGESTED BY THE GFS FORECAST SOUNDINGS AND ECMWF TIME HEIGHTS. RIGHT NOW CONFIDENCE FOR MONDAY IS LOWER BUT DID OPT TO KEEP SOME SLIGHT POPS AT THIS POINT. TEMPERATURES WILL BEGIN ABOVE NORMAL FOR THIS TIME OF YEAR ON THURSDAY. TEMPERATURE FRIDAY BEGIN TO SHIFT TO AT OR NEAR NORMAL BEFORE A BELOW NORMAL SHIFT WITH HIGHS ON POTENTIALLY STAYING IN THE LOW TO MID 70S SUNDAY. THIS WOULD BE 10 OR MORE DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 735 AM EDT TUE JUN 23 2015 VFR CONDITIONS WILL PREVAIL THROUGH THIS EVENING. SOME THUNDERSTORMS MAY DEVELOP ALONG AN APPROACHING COLD FRONT LATER THIS AFTERNOON AND EVENING. COVERAGE IS STILL UNCERTAIN AT THIS TIME...BUT WILL KEEP VCTS TO PROVIDE A WINDOW OF OPPORTUNITY FOR CONVECTION. AS THE FRONT PASSES THIS EVENING...COOLER AIR WILL FILTER INTO THE REGION...BUT MOISTURE MAY LINGER A BIT LONGER WHICH COULD SET THE STAGE FOR SOME DENSE FOG TONIGHT. THIS WILL HAVE THE POTENTIAL TO DROP CIGS OR VISIBILITIES BELOW AIRPORT MINIMUMS LATE TONIGHT. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...KAS SHORT TERM...KAS LONG TERM...DJ AVIATION...KAS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
1010 AM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL PASS THROUGH THE REGION LATE TODAY INTO EARLY TONIGHT. HIGH PRESSURE WILL BRIEFLY BUILD OVERHEAD WEDNESDAY...BUT A WARM FRONT WILL PASS THROUGH THE AREA THURSDAY. LOW PRESSURE WILL RIDE ALONG THE BOUNDARY...PASSING BY TO OUR NORTH FRIDAY AND THIS WILL ALLOW THE BOUNDARY TO DROP THROUGH THE AREA AS A COLD FRONT DURING THE WEEKEND. UNSETTLED CONDITIONS ARE EXPECTED DURING THIS TIME. && .NEAR TERM /THROUGH TONIGHT/... WHILE OUR TWO POTENTIAL HAZARDS REMAIN IN PLACE TODAY...HEAT AND SEVERE WEATHER...THE PICTURE IS STILL SOMEWHAT MUDDLED AT THIS MID MORNING JUNCTURE. THE OVERNIGHT MODELS DID NOT RESOLVE THE EARLY MORNING MCS AND OTHER STORMS ACROSS CENTRAL PA VERY WELL...LEAVING THE HRRR AND RAP AS THE TWO MODELS WHICH GIVE SOME SORT OF INSIGHT INTO WHAT MIGHT UNFOLD. THE OVERALL SYNOPTIC SETUP HAS NOT CHANGED APPRECIABLY WITH A COLD FRONT APPROACHING FROM THE NW. THE AREA WILL BE ON THE SOUTHERN PERIPHERY OF STRONGER WINDS. JUST BY MIXING THE BL OF THE 12Z KIAD RAOB INTO THE MID 90S PRODUCES SBCAPE AOA 2000 J/KG. HOWEVER...STABLE LAYERS IN THE PROFILE (NOTABLY AROUND 400 MB) CAN SOMETIMES INTERFERE WITH UPDRAFT STRENGTH. AM STILL LOOKING FOR DAMAGING WINDS TO BE THE PRIMARY THREAT...ALTHOUGH LARGE HAIL IS ALSO POSSIBLE. SUPPOSE THERE COULD BE A BRIEF TORNADO IF THE RIGHT STORM-SCALE INTERACTION TAKES PLACE...BUT THIS RISK IS VERY LOW. AREAS IMMEDIATELY EAST OF THE MOUNTAINS COULD SEE LESS STORM COVERAGE DUE TO A BIT OF A DOWNSLOPE WIND COMPONENT. THE SOUTHERLY EXTEND OF STORMS IS ALSO QUESTIONABLE DUE TO THE REDUCED SHEAR AND POSSIBLE DIURNAL DOWNTURN...BUT THERE SHOULD BE ENOUGH INSTBY FOR ALREADY-DEVELOPED STORMS TO CONTINUE TO PROSPER. THE BEST WINDOW FOR STORM TIMING WILL BE BETWEEN 2 AND 9 PM. IT LOOKS LIKE THE STORMS WILL BE RATHER PROGRESSIVE BY THE TIME THEY GET HERE...SO THE ACTUAL TIME FRAME MAY BE A BIT QUICKER. THIS WILL ALSO LIMIT THE FLASH FLOOD THREAT...BUT HIGH PWAT/S AND LOW FFG (SOME POCKETS OF LESS THAN ONE INCH) COULD PRODUCE LOCAL ISSUES...ESPECIALLY IN URBAN AREAS. WILL NOT BE MAKING ANY ADJUSTMENTS TO THE HEAT ADVISORY OR HIGH TEMPERATURES WITH THE MORNING UPDATE. HOWEVER...DEBRIS CLOUDINESS COULD PLAY A ROLE IN TEMPERATURE RISES (AND THE INSTBY NOTED ABOVE)...BUT THIS WOULD LIKELY MEAN DEWPOINTS REMAIN HIGHER TOO. WL HV NWLY FLOW DURING THE OVNGT HRS AS DRIER AIR ADVECTS INTO CWFA. DEWPTS LWR-MID 60S. HV REFLECTED THIS IN MIN-T FCST...ALTHO HV HELD ONTO A PINCH OF WARMTH CHO-DCA-DMH. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... THE COLD FRONT SHOULD BE SOUTH OF THE MID-ATLANTIC WEDNESDAY MORNING. NW WINDS WILL BRING COOLER AND DRIER AIR INTO THE REGION COMPARED TO TODAY...TUESDAY. FCST MAX TEMPS IN THE 80S ARE EXPECTED. A CU FIELD IS EXPECTED TO FORM ACROSS THE HIGHLANDS MAINLY NEAR ROANOKE. AT THIS TIME...ONLY AN ISO SHOWER OR THUNDERSTORM IS EXPECTED IN FAR SOUTHERN AUGUSTA/NELSON COUNTIES. CU FIELD WILL DISSIPATE WEDNESDAY NIGHT WITH FCST MIN TEMPS IN THE 60S TO 70S IN THE METROS. CLOUDS WILL INCREASE INTO THURSDAY MORNING AS THE COLD FRONT RETREATS AS A WARM FRONT. THE WARM FRONT WILL CROSS THE REGION THURSDAY CAUSING MOISTURE TO RETURN FROM SW TO NE. 850MB TEMPS WILL INCREASE ABOUT 5 DEG FROM THURSDAY MORNING TO THE EVENING. THIS MOISTURE ADVECTION WILL CAUSE CLOUDS AND SHOWERS AND THUNDERSTORMS TO DEVELOP. THE WARM FRONT WILL CAUSE LOW LEVEL CONVERGENCE WHILE DEWPTS CLIMB INTO THE UPPER 60S ACROSS THE SOUTHERN HALF OF THE CWA. THIS REGION MAY BE PRIME FOR STRONG TO SEVERE STORMS. MODELS ALSO SHOW A THETA-E AXIS SETTING UP ACROSS NC/VA WHICH WILL A PROVIDE ANOTHER AREA OF ENHANCEMENT THURSDAY AFTERNOON. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... LOW PRESSURE WILL DEVELOP ACROSS THE NC/VA THURSDAY NIGHT WHILE ANOTHER AREA OF LOW PRESSURE APPROACHES FROM THE OHIO VALLEY. THIS WILL CONTINUE THE UNSETTLED PERIOD ACROSS THE REGION. BY SATURDAY MORNING...E-NE FLOW FROM THE NORTH MAY BEGIN TO ADVECT STABLE AIR INTO PARTS OF THE NRN MID-ATLANTIC. A LARGE UPPER LEVEL TROUGH WILL DIG INTO THE OHIO VALLEY SATURDAY NIGHT AND DIFFLUENCE ALOFT WILL LIKELY LEAD TO ENHANCE SHOWERS AND THUNDERSTORMS. THE ATMOSPHERE SEEMS TO BE VERY SATURATED THIS WEEKEND AND MAY RESULT IN PERIODS OF HEAVY RAIN. TEMPS WILL LIKELY BE BELOW NORMAL THIS WEEKEND. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... VFR THROUGH MIDDAY. WSWLY WINDS WL INCR DURING THE MIDDAY HRS...W/ SOME GUSTS UP TO 20 KT. A CDFNT WL APPROACH THE TERMINALS LT...MOST LKLY DURING THE EVNG. BUT TSRA WL LKLY DVLP AHD OF THE FNT...IMPACTING THE AFTN PUSH. DID NOT TAKE FLGT RESTRICTIONS IN TAFS DUE TO AREAL CVRG/TIMING CONSIDERATIONS...BUT BRIEF IFR WELL W/IN REASON. VCTS RMK ADDED FOR A FAIRLY LONG DURATION. WL WORK TO NARROW THAT WINDOW DOWN IN TAF CYCLES TO COME. VFR CONDITIONS EXPECTED WEDNESDAY THROUGH THURSDAY. A WARM FRONT WILL MOVE THROUGH THE REGION THURSDAY. SHRA/TSRA SEEM TO BE CONFINED OUTSIDE THE TERMINALS. SHRA/VCTS POSSIBLE THURSDAY NIGHT THROUGH SATURDAY. && .MARINE... WINDS REMAINING BLO SCA CRITERIA IN SSWLY FLOW ATTM...BUT ITS ADMITTEDLY CLS. SCA WILL GO INTO EFFECT AT 11 AM. AM STILL CARRYING SCA DURING THE MIDDAY-AFTN HRS AS PRES GRADIENT INCREASES AHD OF APPROACHING CDFNT. MEAN MIXED LYR WINDS SHUD BE ARND 20 KT...SO ITS A FAIRLY SOLID SCA. OVERLAPPING WITH THE GRADIENT WIND...NMRS TSRA WL BE DVLPG LT DAY INTO THE EVNG HRS. THESE STORMS WL FEED OFF OF THE HUMID AMS AND PRODUCE STRONG/LCLLY DMGG GUSTS. MARINE WARNINGS /SMW/ WL LKLY BE ISSUED THIS PM. THERE WL BE A BIT OF A LULL IN TERMS OF SUSTAINED WIND /OUTSIDE OF TSRA/ IN THE LATE ENVG BEFORE NW FLOW KICKS IN. A PRESSURE SURGE BEHIND THE COLD FRONT TONIGHT INTO WEDNESDAY WILL RESULT IN SCA CONDITIONS ON THE WATERS. NW WINDS WILL DIMINISH BY WEDNESDAY AFTERNOON. A WARM FRONT MOVES ACROSS THE WATERS THURSDAY. UNSETTLED CONDITIONS THURSDAY THROUGH THE WEEKEND WILL RESULT IN PERIODS OF SHOWERS AND THUNDERSTORMS. && .TIDES/COASTAL FLOODING... WATER LEVELS RUNNING ABOUT A HALF-FOOT ABV ASTRO NORMS. ALTHOUGH WINDS WILL INCREASE LATER TODAY...DO NOT BELIEVE THE DIRECTIONS WL BE APPROPRIATE TO ADD MUCH TO THE DEPARTURE. DO NOT BELIEVE ANY SITE WL EVEN REACH CAUTION STAGE. && .CLIMATE... RECORD MAXIMUM TEMPERATURES FOR TODAY... DCA...98 SET IN 1988 AND 1874 IAD...96 SET IN 1988 AND 1965 BWI...97 SET IN 2010 AND 1894 && .LWX WATCHES/WARNINGS/ADVISORIES... DC...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EDT THIS EVENING FOR DCZ001. MD...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EDT THIS EVENING FOR MDZ011-013-014-016>018-504-506-508. VA...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EDT THIS EVENING FOR VAZ052>057. WV...NONE. MARINE...HEAT ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EDT THIS EVENING FOR ANZ535-536-538-542. SMALL CRAFT ADVISORY UNTIL 9 PM EDT THIS EVENING FOR ANZ530>543. SMALL CRAFT ADVISORY FROM 2 AM TO 10 AM EDT WEDNESDAY FOR ANZ530>534-537>543. && $$ SYNOPSIS...HTS NEAR TERM...ADS/HTS SHORT TERM...HAS LONG TERM...HAS AVIATION...HAS/HTS MARINE...HAS/HTS TIDES/COASTAL FLOODING...HTS CLIMATE...HTS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
840 AM EDT TUE JUN 23 2015 .SYNOPSIS... A CROSSING COLD FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE STRONG TO SEVERE...ON TUESDAY. HIGH PRESSURE RETURNS WEDNESDAY. UNSETTLED...BUT LESS HUMID WEATHER RETURNS FOR LATE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... FORECAST UPDATE WAS TO REFLECT LATEST RADAR TRENDS AND FOCUS HIGH POPS SOUTH OF THE U.S. 422 CORRIDOR TODAY WITH CATEGORICAL POPS FOR A LARGE PORTION OF THE AREA SAVE FOR EASTERN OHIO. HIGH RES CONVECTIVE ALLOWING MODELS ARE POINTING TO A STRONG TO SEVERE LINE OF STORMS TRAVERSING SOUTH OF I-76 THIS AFTERNOON. WITH TEMPS ONLY FALLING BACK INTO THE UPPER 70S OVERNIGHT COUPLED WITH BREAKS IN THE CLOUDS...ATMOSPHERE ALREADY PRIMED FOR CONVECTION. LATEST 12Z PIT RAOB INDICATES A DAMAGING WIND THREAT WITH UNIDIRECTIONAL SHEAR AND O-6KM WINDS AROUND 40KTS. RAIN RATES HAVE NOT BEEN TOO IMPRESSIVE...SO DESPITE A LITTLE TRAINING OVER THE I-80 REGION...DO NOT SEE A HIGH WATER THREAT. ADDED GUSTY WIND ATTRIBUTE TO WEATHER GRIDS AND MAY NEED TO INCLUDE DAMAGING WINDS IN LATER UPDATES. PREVIOUS DISCUSSION... MODEL SOLUTIONS FAVOR INITIAL ACTIVITY DEPARTING OUR AREA BY LATE MORNING/EARLY AFTERNOON. HOWEVER...A QUICK GLANCE AT REGIONAL OBSERVATIONS REVEALS THAT ONGOING CONVECTION IS LARGELY UNTIED TO THE MAIN FRONTAL BOUNDARY OVER MICHIGAN AND NORTHERN ILLINOIS. LARGER SCALE MODELS SEEM TO TRY TO TIE THESE TWO THINGS TOGETHER RATHER QUICKLY ON TODAY...HOWEVER THE FINER SCALE MODELS MAINTAIN A DISTINCTION BETWEEN THE TWO. THE NAM IN PARTICULAR HAS BEEN INSISTENT ON THIS FOR SEVERAL RUNS...AND EVEN THE HRRR FAVORS CONVECTIVE REDEVELOPMENT THIS AFTERNOON. OBSERVATIONS REALLY DO NOT FAVOR THE FRONT CATCHING UP TO ONGOING CONVECTION THIS MORNING IN ANY FASHION...SO THE FORECAST STILL HEAVILY FAVORS REDEVELOPMENT AHEAD OF SAID FRONT THIS AFTERNOON. THIS BRINGS A WHOLE HOST OF PROBLEMS WITH IT. BULK SHEAR VALUES OF 45-50 KTS WITH SOME MODEST VEERING IS EVIDENT ON NAM SOUNDINGS AHEAD OF THE FRONT. ADDITIONALLY...MODEL PWATS SURGE TOWARD AND ABOVE 2 INCHES ALONG THE FRONT WITH CAPE VALUES JUMPING TOWARD 2000 J/KG. THIS IS EVEN WITHOUT A STRONG SIGNAL FOR CLEARING AHEAD OF THE FRONT. THAT SAID...SPC IS MAINTAINING THE SLIGHT RISK FOR SEVERE THUNDERSTORMS...WHICH SEEMS WARRANTED. THE MAIN THREAT DOES SEEM LIKELY TO BE DAMAGING WINDS...HOWEVER A SPINNER OR TWO CANNOT BE RULED OUT GIVEN THE LOW LEVEL WIND FIELD THAT SEEMS LIKELY TO BE CHARACTERISTIC OF THE PRE-FRONTAL ENVIRONMENT. IN MUST BE NOTED...HOWEVER...THAT GFS/SREF SOLUTIONS FAVOR THE FASTER FRONTAL MOVEMENT AND LACK OF DEEP CONVECTIVE REDEVELOPMENT. BUT GIVEN THAT "THE TREND IS YOUR FRIEND"...THEY HAVE LARGELY BEEN CONSIDERED THE LESS LIKELY SCENARIOS. GIVEN A VERY WARM START TO THE DAY TODAY...AND STRONG MIXING LIKELY...HIGHS SHOULD EASILY JUMP INTO THE 80S...MAKING THOSE 2000 J/KG CAPE VALUES EASY TO ATTAIN...EVEN WITHOUT STRONG ISOLATION. MODEL AGREEMENT INCREASES GREATLY BEHIND THE FRONT...AS PWATS FALL OFF A CLIFF AND LAYER RH VALUES DO LIKEWISE. POPS RAPIDLY WILL FALL TO NEAR ZERO IN THE POST-FRONTAL ENVIRONMENT...AND DEWPOINTS WILL LIKELY FALL OFF A CLIFF AS WELL. THIS WILL YIELD A SUBSTANTIALLY NICER TUESDAY NIGHT AND WEDNESDAY AS THE SOUP WE HAVE BECOME ACCUSTOMED TO FINALLY DEPARTS FOR AT LEAST A BRIEF INTERLUDE. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... SURFACE HIGH PRESSURE WILL KEEP CONDITIONS DRY WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BUT ZONAL FLOW ALOFT MEANS TRANQUIL WEATHER WILL BE FLEETING. A MID-LEVEL WAVE...ASSOCIATED WITH CONVECTION OVER THE CORNBELT...WILL APPROACH THE GREAT LAKES BY DAY BREAK THURSDAY. REMNANTS OF THE EARLIER CONVECTION WILL APPROACH THE FORECAST AREA DURING A CLIMATOLOGICALLY UNFAVORABLE TIME...AND SHOULD BE DISSIPATING ON ENTRANCE. THURSDAY AFTERNOON SHOULD BRING A RE-INVIGORATION OF SHOWERS AND THUNDERSTORMS ALONG THE NOSE OF THE LOW. IMPRESSIVE SHEAR VALUES WILL EXIST ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA...NEAR THE BASE OF THE WAVE. HOWEVER...REMNANT CLOUD COVER WILL QUELL THE MORNING WARM-UP AND SERVE TO STABILIZE A MAJORITY OF THE FORECAST AREA...DESPITE STEEPENING MID-LEVEL LAPSE RATES AS COOL AIR ALOFT MOVES IN. THE SOUTHERN PERIPHERY OF THE FORECAST AREA WILL HAVE THE BEST CHANCE TO HOLD SOME SUN...AND THUS THE BETTER OPPORTUNITY TO DESTABILIZE. IF ANY STRONG TO SEVERE STORMS WERE TO EXIST THURSDAY EVENING...THIS IS WHERE THEY WILL RESIDE. FRIDAY THE UPPER-LEVEL FLOW FLATTENS WEST TO EAST AND THE WEAK SURFACE LOW STAGNATES OVER THE OHIO RIVER VALLEY. THE RESULT IS THAT MOISTURE NEVER CLEARS THE SOUTHERN 1/2 OF THE FORECAST AREA...KEEPING RAIN CHANCES HIGHER THROUGH FRIDAY EVENING WITH ANOTHER AFTERNOON FLARE-UP OF CONVECTION OVER THE HIGH TERRAIN OF PA/WV/MD. TAX && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AN UPPER-LEVEL WAVE PASSING THROUGH THE WESTERN GREAT LAKES FRIDAY NIGHT WILL SERVE TO AMPLIFY THE MERIDIONAL FLOW PATTERN. PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL LINGER...MAINLY ACROSS OUR SOUTH. BY THE MIDDLE PART OF THE WEEKEND THE EASTERN CONUS TROF IS IN FULL EFFECT WITH INCREASED CLOUD COVER RESULTING IN MODERATED TEMPERATURE READINGS. GUIDANCE DIFFERS A BIT ON THE EXACT EVOLUTION OF THE UPPER-LEVEL TROF...WITH THE WETTER GFS CUTTING OFF THE LOW DIRECTLY OVERHEAD. REGARDLESS OF THE MINUTIAE...IT APPEARS AS TROF WILL BE HERE TO STAY AS A RE-ENFORCING WAVE WILL DIVE IN FROM THE NORTHWEST BY EARLY NEXT WEEK. TAX && .AVIATION /13Z TUESDAY THROUGH SATURDAY/... HIGH CONFIDENCE FORECAST OUTSIDE TIMING OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH A COLD FRONT. ONGOING SHOWERS WILL DEPART FKL AND DUJ BY 13-14Z LEAVING BKN MVFR OR VFR WEATHER IN ITS WAKE. EXPECT CLOUDS TO BREAK UP THIS MORNING INTO THE AFTERNOON HOURS AS IR SATELLITE PICTURE ILLUSTRATES CLOUD TOPS WARMING OVER OHIO AND INDIANA. WITH SOME DAYTIME HEATING...THIS WILL SET THE STAGE FOR A LINE OF STORMS TO DEVELOP BY EARLY AFTERNOON SOUTH OF I-80/U.S. 422 MOVING SSE THROUGH EARLY EVENING. STORMS LIKELY WILL DEVELOP ON SOUTHERN PERIPHERY OF ONGOING ACTIVITY. BRIEF IFR VIS RESTRICTIONS ARE FORECAST...HOWEVER WITH IT BEING SUCH SHORT DURATION...DID NOT INCLUDE ANYTHING LOWER THAN MVFR IN THE TAF. IN FACT...MOSTLY CARRIED VCTS UNTIL THINGS DEVELOP. AFTER THE FRONT PASSES WINDS WILL SHIFT TO THE NORTH AND DRIER AIR INFILTRATES THE REGION. THIS SHOULD OFFSET ANY FOG DEVELOPMENT DURING THE OVERNIGHT HOURS. .OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE POSSIBLE BY LATE WEEK WITH CROSSING LOW PRESSURE. && .CLIMATE... THE OVERNIGHT LOW SO FAR HAS BEEN 77 DEGREES AT PITTSBURGH...THE RECORD LOW HIGH FOR THIS DATE IS 76 SET WAY BACK IN 1888. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ NEAR TERM...98/FRIES SHORT TERM...TAX LONG TERM...TAX AVIATION...98 CLIMATE...98
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
750 AM EDT TUE JUN 23 2015 .SYNOPSIS... A CROSSING COLD FRONT WILL BRING THE CHANCE FOR SHOWERS AND THUNDERSTORMS...SOME OF WHICH MAY BE STRONG TO SEVERE...ON TUESDAY. HIGH PRESSURE RETURNS WEDNESDAY. UNSETTLED...BUT LESS HUMID WEATHER RETURNS FOR LATE WEEK. && .NEAR TERM /THROUGH WEDNESDAY/... A FAIRLY COMPLICATED NEAR TERM SCENARIO SEEMS SET TO PLAY OUT OVER THE NEXT 24 HOURS ACROSS THE UPPER OHIO VALLEY AS ONGOING CONVECTION TO OUR NORTH AND WEST PLAY A ROLE IN THE MORNING FORECAST...WHILE THE EVOLUTION OF SAID CONVECTION...ITS BLOW OFF...AND DEBRIS...HAVE LARGE RAMIFICATIONS UPON THE EVENTUAL DEVELOPMENT OR LACK THEROF AHEAD OF A COLD FRONT AS IT SLICES THROUGH THE AREA LATER TODAY...BRING A WHOLESALE AIR MASS CHANGE IN OUR REGION. LET`S TRY TO BREAK THIS DOWN... MODEL TRENDS HAVE FAVORED IMPRESSIVE CONVECTIVE DEVELOPMENT OVER THE CENTRAL GREAT LAKES THROUGH EARLY THIS MORNING FOR SEVERAL DAYS...AND BOY HAS THE CONVECTION REALLY GOTTEN ROLLING OVERNIGHT. HOWEVER...CONVECTIVE TRENDS...MODEL SOUNDINGS...AND TRENDS IN LIGHTNING DATA SUGGEST THIS CONVECTION IS BECOMING LESS FIERCE AS IT MOVES OFF OF LAKE ERIE. THIS ACTIVITY IS LARGELY ANCHORED TO UPPER FORCING...WHICH IS TRENDING EASTWARD...HOWEVER INDIVIDUAL CONVECTIVE VORTS ARE ALLOWING FOR SOME SOUTHWARD PROPAGATION OF THE LINE AT THE MOMENT. THIS WILL ALLOW STORMS OVER NORTHERN OHIO TO TREND TOWARD I-80 OVER THE NEXT COUPLE OF HOURS...EVEN WHILE THE BULK OF THE FORCING TRANSLATES TO THE EAST GENERALLY NORTH OF THE AREA. WHILE THE BULK OF THE UPPER FORCING MOVES EASTWARD...WEAK SHORT WAVE TROUGHING DOES SEEM POISED TO DROP THROUGH THE CWA THIS MORNING PER MODEL GUIDANCE. GIVEN THE AIR MASS...IT SEEMS UNLIKELY THIS WOULD ENTIRELY DISSIPATE...HOWEVER THE BOUNDARY LAYER IS NOT ENTIRELY FAVORABLE FOR STRONG DOWNWARD MIXING POTENTIAL...SO IT WOULD SEEM ELEVATED CONVECTION WILL BE THE MAIN PROBLEM. ADDITIONALLY...GIVEN PROGRESSIVE FORCING...RAINFALL SHOULD BE PROGRESSIVE...WHICH WILL MINIMIZE FLOODING CONCERNS THROUGH MORNING. MODEL SOLUTIONS FAVOR INITIAL ACTIVITY DEPARTING OUR AREA BY LATE MORNING/EARLY AFTERNOON. HOWEVER...A QUICK GLANCE AT REGIONAL OBSERVATIONS REVEALS THAT ONGOING CONVECTION IS LARGELY UNTIED TO THE MAIN FRONTAL BOUNDARY OVER MICHIGAN AND NORTHERN ILLINOIS. LARGER SCALE MODELS SEEM TO TRY TO TIE THESE TWO THINGS TOGETHER RATHER QUICKLY ON TODAY...HOWEVER THE FINER SCALE MODELS MAINTAIN A DISTINCTION BETWEEN THE TWO. THE NAM IN PARTICULAR HAS BEEN INSISTENT ON THIS FOR SEVERAL RUNS...AND EVEN THE HRRR FAVORS CONVECTIVE REDEVELOPMENT THIS AFTERNOON. OBSERVATIONS REALLY DO NOT FAVOR THE FRONT CATCHING UP TO ONGOING CONVECTION THIS MORNING IN ANY FASHION...SO THE FORECAST STILL HEAVILY FAVORS REDEVELOPMENT AHEAD OF SAID FRONT THIS AFTERNOON. THIS BRINGS A WHOLE HOST OF PROBLEMS WITH IT. BULK SHEAR VALUES OF 45-50 KTS WITH SOME MODEST VEERING IS EVIDENT ON NAM SOUNDINGS AHEAD OF THE FRONT. ADDITIONALLY...MODEL PWATS SURGE TOWARD AND ABOVE 2 INCHES ALONG THE FRONT WITH CAPE VALUES JUMPING TOWARD 2000 J/KG. THIS IS EVEN WITHOUT A STRONG SIGNAL FOR CLEARING AHEAD OF THE FRONT. THAT SAID...SPC IS MAINTAINING THE SLIGHT RISK FOR SEVERE THUNDERSTORMS...WHICH SEEMS WARRANTED. THE MAIN THREAT DOES SEEM LIKELY TO BE DAMAGING WINDS...HOWEVER A SPINNER OR TWO CANNOT BE RULED OUT GIVEN THE LOW LEVEL WIND FIELD THAT SEEMS LIKELY TO BE CHARACTERISTIC OF THE PRE-FRONTAL ENVIRONMENT. IN MUST BE NOTED...HOWEVER...THAT GFS/SREF SOLUTIONS FAVOR THE FASTER FRONTAL MOVEMENT AND LACK OF DEEP CONVECTIVE REDEVELOPMENT. BUT GIVEN THAT "THE TREND IS YOUR FRIEND"...THEY HAVE LARGELY BEEN CONSIDERED THE LESS LIKELY SCENARIOS. GIVEN A VERY WARM START TO THE DAY TODAY...AND STRONG MIXING LIKELY...HIGHS SHOULD EASILY JUMP INTO THE 80S...MAKING THOSE 2000 J/KG CAPE VALUES EASY TO ATTAIN...EVEN WITHOUT STRONG ISOLATION. MODEL AGREEMENT INCREASES GREATLY BEHIND THE FRONT...AS PWATS FALL OFF A CLIFF AND LAYER RH VALUES DO LIKEWISE. POPS RAPIDLY WILL FALL TO NEAR ZERO IN THE POST-FRONTAL ENVIRONMENT...AND DEWPOINTS WILL LIKELY FALL OFF A CLIFF AS WELL. THIS WILL YIELD A SUBSTANTIALLY NICER TUESDAY NIGHT AND WEDNESDAY AS THE SOUP WE HAVE BECOME ACCUSTOMED TO FINALLY DEPARTS FOR AT LEAST A BRIEF INTERLUDE. FRIES && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... SURFACE HIGH PRESSURE WILL KEEP CONDITIONS DRY WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING...BUT ZONAL FLOW ALOFT MEANS TRANQUIL WEATHER WILL BE FLEETING. A MID-LEVEL WAVE...ASSOCIATED WITH CONVECTION OVER THE CORNBELT...WILL APPROACH THE GREAT LAKES BY DAY BREAK THURSDAY. REMNANTS OF THE EARLIER CONVECTION WILL APPROACH THE FORECAST AREA DURING A CLIMATOLOGICALLY UNFAVORABLE TIME...AND SHOULD BE DISSIPATING ON ENTRANCE. THURSDAY AFTERNOON SHOULD BRING A RE-INVIGORATION OF SHOWERS AND THUNDERSTORMS ALONG THE NOSE OF THE LOW. IMPRESSIVE SHEAR VALUES WILL EXIST ACROSS THE SOUTHERN PORTION OF THE FORECAST AREA...NEAR THE BASE OF THE WAVE. HOWEVER...REMNANT CLOUD COVER WILL QUELL THE MORNING WARM-UP AND SERVE TO STABILIZE A MAJORITY OF THE FORECAST AREA...DESPITE STEEPENING MID-LEVEL LAPSE RATES AS COOL AIR ALOFT MOVES IN. THE SOUTHERN PERIPHERY OF THE FORECAST AREA WILL HAVE THE BEST CHANCE TO HOLD SOME SUN...AND THUS THE BETTER OPPORTUNITY TO DESTABILIZE. IF ANY STRONG TO SEVERE STORMS WERE TO EXIST THURSDAY EVENING...THIS IS WHERE THEY WILL RESIDE. FRIDAY THE UPPER-LEVEL FLOW FLATTENS WEST TO EAST AND THE WEAK SURFACE LOW STAGNATES OVER THE OHIO RIVER VALLEY. THE RESULT IS THAT MOISTURE NEVER CLEARS THE SOUTHERN 1/2 OF THE FORECAST AREA...KEEPING RAIN CHANCES HIGHER THROUGH FRIDAY EVENING WITH ANOTHER AFTERNOON FLARE-UP OF CONVECTION OVER THE HIGH TERRAIN OF PA/WV/MD. TAX && .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... AN UPPER-LEVEL WAVE PASSING THROUGH THE WESTERN GREAT LAKES FRIDAY NIGHT WILL SERVE TO AMPLIFY THE MERIDIONAL FLOW PATTERN. PRECIPITATION CHANCES WILL CONTINUE INTO THE WEEKEND AS MOISTURE ASSOCIATED WITH THE SURFACE LOW WILL LINGER...MAINLY ACROSS OUR SOUTH. BY THE MIDDLE PART OF THE WEEKEND THE EASTERN CONUS TROF IS IN FULL EFFECT WITH INCREASED CLOUD COVER RESULTING IN MODERATED TEMPERATURE READINGS. GUIDANCE DIFFERS A BIT ON THE EXACT EVOLUTION OF THE UPPER-LEVEL TROF...WITH THE WETTER GFS CUTTING OFF THE LOW DIRECTLY OVERHEAD. REGARDLESS OF THE MINUTIAE...IT APPEARS AS TROF WILL BE HERE TO STAY AS A RE-ENFORCING WAVE WILL DIVE IN FROM THE NORTHWEST BY EARLY NEXT WEEK. TAX && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... HIGH CONFIDENCE FORECAST OUTSIDE TIMING OF SHOWERS AND THUNDERSTORMS THIS AFTERNOON WITH A COLD FRONT. ONGOING SHOWERS WILL DEPART FKL AND DUJ BY 13-14Z LEAVING BKN MVFR OR VFR WEATHER IN ITS WAKE. EXPECT CLOUDS TO BREAK UP THIS MORNING INTO THE AFTERNOON HOURS AS IR SATELLITE PICTURE ILLUSTRATES CLOUD TOPS WARMING OVER OHIO AND INDIANA. WITH SOME DAYTIME HEATING...THIS WILL SET THE STAGE FOR A LINE OF STORMS TO DEVELOP BY EARLY AFTERNOON SOUTH OF I-80/U.S. 422 MOVING SSE THROUGH EARLY EVENING. STORMS LIKELY WILL DEVELOP ON SOUTHERN PERIPHERY OF ONGOING ACTIVITY. BRIEF IFR VIS RESTRICTIONS ARE FORECAST...HOWEVER WITH IT BEING SUCH SHORT DURATION...DID NOT INCLUDE ANYTHING LOWER THAN MVFR IN THE TAF. IN FACT...MOSTLY CARRIED VCTS UNTIL THINGS DEVELOP. AFTER THE FRONT PASSES WINDS WILL SHIFT TO THE NORTH AND DRIER AIR INFILTRATES THE REGION. THIS SHOULD OFFSET ANY FOG DEVELOPMENT DURING THE OVERNIGHT HOURS. .OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... RESTRICTIONS ARE POSSIBLE BY LATE WEEK WITH CROSSING LOW PRESSURE. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$ NEAR TERM...FRIES SHORT TERM...TAX LONG TERM...TAX AVIATION...98
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
958 AM MDT TUE JUN 23 2015 .UPDATE... A WEAK SHORTWAVE WAS PUSHING THROUGH SOUTH CENTRAL MONTANA THIS MORNING. SHORTWAVE GENERATING A FEW ACCAS...BUT NOTHING IN THE WAY OF PRECIPITATION. 12Z NAM KEEPS THE AREA DRY THIS MORNING AS DOES THE HRRR. REMOVED POPS FROM THE WEST THIS MORNING WITH THIS THOUGHT IN MIND. REST OF THE FORECAST LOOKS IN GOOD SHAPE. MORNING SHORTWAVE ENTERS THE EAST THIS AFTERNOON. THIS COULD KICK OFF CONVECTION OVER SOUTHEAST MONTANA. RAISED POPS A BIT MORE FROM MILES CITY EASTWARD. CAPES PROGGED TO AROUND 1000 J/KG ON THE GFS WITH NEAR 1500 J/KG ON THE NAM. EFFECTIVE BULK SHEAR AROUND 50 KTS. POTENTIAL IS CERTAINLY THERE FOR SEVERE WEATHER THIS AFTERNOON OVER THE EAST AND WILL KEEP THE MENTION. CAPES AND SHEAR WEAKER IN THE WEST...SO NOT OVERLY CONCERNED SEVERE WEATHER THERE. THAT BEING SAID...EFFECTIVE BULK SHEAR DOES GET TO AROUND 30 KTS OVER THE WEST...ACCORDING TO THE RAP...SO SMALL HAIL NOT OUT OF THE QUESTION. TWH && .SHORT TERM...VALID FOR TDY AND WED... AS OF 0830Z AN AREA OF SHOWERS WITH A FEW LIGHTNING STRIKES EXISTS FROM NEAR HARDIN TO CARTER COUNTY. THIS A RESULT OF SOUTHEASTERLY LOW LEVEL JET AND MODEST ELEVATED INSTABILITY...AND LATEST PWAT ANALYSIS SHOWS VALUES NEAR AN INCH ACROSS OUR SOUTHEAST AS WE CONTINUE TO ADVECT MOISTURE UP THE HIGH PLAINS. FORCING FROM LOW LEVEL JET SHOULD DIMINISH EARLY THIS MORNING AND THIS IS CONSISTENT WITH RECENT HRRR RUNS...THUS EXPECT SHOWER ACTIVITY TO END OVER OUR SOUTHEAST A LITTLE AFTER SUNRISE. LOOKING TO THE WEST...THERE IS AN AREA OF PV MOVING FROM OR TO CENTRAL ID. THIS FEATURE SHOULD PROVIDE ASCENT FOR SHOWER AND THUNDERSTORM DEVELOPMENT LATER TODAY. IN FACT...WOULD NOT BE SURPRISED TO SEE SOME SHOWER ACTIVITY DEVELOP BEFORE NOON ACROSS OUR WEST PER TIMING OF THIS SHORTWAVE. WE ARE STILL EXPECTING A RISK OF SEVERE STORMS ACROSS OUR EAST THIS AFTERNOON AND EVENING PER CAPES OF 1200+ J/KG AND UP TO 50 KTS OF EFFECTIVE BULK SHEAR...AND ASCENT PROVIDED BY THE APPROACHING SHORTWAVE. HRRR/RAP SHOW A SURGE OF DRIER MIXED WEST WINDS PUSHING THRU MLS-4BQ. THIS WOULD SUGGEST DEEPER MOISTURE AND BEST SEVERE POTENTIAL WOULD BE CLOSE TO THE DAKOTAS BORDER... AND THIS MAY BE REASONABLE GIVEN SHORTWAVE WILL MOVE INTO SOUTHEAST MT AS EARLY AS 18Z. WILL NEED TO KEEP WATCH OF THIS. NEXT SHORTWAVE OVER NORTHERN WA WILL MOVE ACROSS THE HIGH LINE TONIGHT. WEAKER LOW LEVEL JET PLUS FORCING FROM THIS ENERGY WILL KEEP SHOWER AND TSTM CHANCES GOING THROUGH THE NIGHT ESPECIALLY FOR OUR EAST. COULD SEE TWO SEPARATE ROUNDS OF POTENTIAL SEVERE STORMS...ONE IN THE AFTERNOON AS ALREADY MENTIONED AND A SECOND IN THE EVENING PER THE SECONDARY SHORTWAVE. HAIL AND WIND ARE THE PRIMARY THREATS. YET ANOTHER SHORTWAVE IN THE PACIFIC FLOW ALOFT WILL MOVE INTO THE AREA WEDNESDAY. GFS/NAM SHOW EASTERLY LOW LEVEL FLOW PERSISTING ACROSS OUR EAST THROUGH WEDNESDAY...ALLOWING FOR HIGH PWATS AND DEEPER INSTABILITY AND IN FACT THE GFS SHOWS LIFTED INDICES TO -5C IN SOUTHEAST MT WEDNESDAY AFTERNOON. SHEAR WILL AGAIN BE SUFFICIENT FOR ORGANIZED STORMS AND FEEL THAT STRONG TO SEVERE ACTIVITY IS POSSIBLE TOMORROW AS WELL...AGAIN MAINLY IN OUR EAST. SMALL HAIL AND GUSTY WINDS STILL A POSSIBILITY FOR OUR WESTERN AREAS WITH CONVECTION TODAY AND WEDNESDAY. TEMPS WILL TURN WARMER TODAY WITH HIGHS GETTING INTO THE LOWER TO MID 80S. SHOULD BE SLIGHTLY COOLER WEDNESDAY BUT STILL A LITTLE ABOVE NORMAL. JKL .LONG TERM...VALID FOR THU...FRI...SAT...SUN...MON... DEVELOPING RIDGE OVER IDAHO BEGINS TO INCREASE HEIGHTS OVER THE WESTERN ZONES ON THURSDAY BRINGING A MORE STABLE PATTERN. STILL HINTS OF SOUTHEASTERLY SURFACE FLOW ALONG THE MONTANA DAKOTA BORDER SO CANNOT COMPLETELY RULE OUT THUNDERSTORMS IN SOUTHEAST MONTANA. FOR FRIDAY AND BEYOND A DOMINANT RIDGE BEGINS TO BUILD OVER IDAHO AND WESTERN MONTANA AND LATEST RUNS SHIFT IT A BIT EASTWARD EARLY NEXT WEEK. THIS WILL SEVERELY LIMIT CONVECTIVE POTENTIAL AND BRING SUMMER LIKE TEMPERATURES...WITH READINGS 95 TO 100 POSSIBLE BY SUNDAY THROUGH TUESDAY. BORSUM && .AVIATION... A COUPLE OF ROUNDS OF THUNDERSTORMS ARE POSSIBLE THIS AFTERNOON AND THEN AGAIN THIS EVENING. RIGHT NOW GUIDANCE IS VERY UNCERTAIN ON THE PLACEMENT AND TIMING. THE BEST CHANCES WILL BE FROM MILES CITY EAST...ALTHOUGH THE LATER STORMS COULD FORM FARTHER TO THE WEST AND COULD POSSIBLY IMPACT BILLINGS. THESE STORMS COULD PRODUCE MVFR TO IFR CONDITIONS ALONG WITH STRONG GUSTY WINDS AND LARGE HAIL. FOR THE REST OF THE THE NEXT 24 HOURS VFR FLIGHT CONDITIONS WILL PREVAIL. REIMER && .PRELIMINARY POINT TEMP/POPS... TDY WED THU FRI SAT SUN MON ------------------------------------------------------- BIL 084 059/082 060/086 059/090 062/093 063/095 063/097 2/T 32/T 21/E 11/U 00/U 01/U 11/U LVM 084 049/084 053/086 052/091 054/095 056/096 056/097 3/T 32/T 21/B 11/U 00/U 11/U 11/U HDN 087 056/086 059/087 059/091 061/094 062/096 062/097 2/T 32/T 22/T 11/U 11/U 11/U 11/U MLS 085 059/083 060/084 059/087 061/090 061/092 063/093 3/T 44/T 32/T 32/T 10/U 01/U 11/U 4BQ 083 057/083 059/082 058/085 059/089 059/092 061/092 2/T 44/T 33/T 31/B 11/U 11/U 11/U BHK 080 057/080 058/081 057/082 058/086 058/088 060/087 3/T 54/T 33/T 32/T 21/U 11/U 11/U SHR 082 053/081 055/081 054/084 055/088 055/090 057/091 2/T 32/T 33/T 21/B 11/U 11/U 11/U && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1004 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH FRIDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM TUESDAY... MORNING UPDATE: TEMPERATURES ON TRACK FOR UPPER 90S TODAY WITH A FEW SPOTS TOUCHING THE HUNDRED DEGREE MARK. AS OF 1000 AM...MOST LOCATIONS IN THE MID 80S ALREADY WITH HEAT INDICES IN THE LOW 90S. MAY BE HARD TO REACH THE 105 DEGREE HEAT ADVISORY CRITERIA TODAY IN MOST SPOTS BUT WITH VERY PERSISTENT HEAT THE LAST SEVERAL DAYS AND LIKELY HEAT INDICES BETWEEN 100-105 DEGREES...HAVE A HEAT ADVISORY IN EFFECT FROM NOON UNTIL 700 PM FOR POINTS EAST OF HIGHWAY 1. A SURFACE TROUGH IS ALSO SETTING UP RIGHT ALONG HIGHWAY 1. TO THE EAST OF HERE...MOISTURE WILL BE HIGHER AND THUS THE HIGHER HEAT INDICES. THIS AREA COULD BE A FOCUS FOR SOME DIURNAL CONVECTION AS WELL WHICH WE WILL MONITOR FOR THIS AFTERNOON. PREVIOUS DISCUSSION FOLLOWS. -ELLIS MID LEVEL HEIGHTS WILL INCREASE A BIT MORE TODAY... WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 7 TO 8 METERS HIGHER TODAY. THUS... GIVEN SIMILAR CONDITIONS EXPECT WE SHOULD SEE HIGH TEMPS GENERALLY 2-3 DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS. THIS SHOULD RESULT IN HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES ACROSS THE AREA. THIS COMBINED WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA SHOULD RESULT IN SEVERAL HOURS OF HEAT INDEX VALUES THIS AFTERNOON OF AROUND 105 DEGREES OR HIGHER. THUS... CURRENT HEAT ADVISORY LOOKS GOOD WITH NO CHANGES PLANNED AT THIS TIME. IN ADDITION TO THE HEAT... WE MAY SEE SOME AFTERNOON SHOWERS AND STORMS DEVELOP ALONG A REMNANT OUTFLOW AND MCV THAT IS CURRENTLY SINKING SOUTH AND EASTWARD INTO THE FA. THE LATEST RAP SHOWS THIS FEATURE SLOWLY SHIFTING SOUTH AND EASTWARD ACROSS CENTRAL NC THIS MORNING... WITH POSSIBLY A FEW WEAK SHOWERS DEVELOPING ALONG IT (NOTHING CURRENTLY ON RADAR). HOWEVER... AS THE FEATURE SHIFTS EASTWARD ACROSS THE AREA LATER TODAY... THINK WE MAY SEE SOME DEVELOPMENT ACROSS OUR SOUTHEASTERN/EASTERN COUNTIES... WHICH IS LOOSELY SHOWN BY SOME OF THE HIGH-RES GUIDANCES. GIVEN MODERATE INSTABILITY (IF WE INDEED GET SOME STORMS TO DEVELOP) WE COULD SEE A FEW STRONG TO PERHAPS SEVERE STORMS... MAINLY PULSE IN NATURE GIVEN CONTINUED WEAK DEEP LAYER SHEAR. THE NEXT FEATURE OF INTERESTED TODAY INTO THIS EVENING WILL BE THE APPROACH OF A COLD FRONT AND A CLUSTER OR LINE OF SHOWERS AND STORMS IN ADVANCE OF THE FRONT. SOME OF THE HI-RES (CAM`S) GUIDANCES SHOWS THIS LINE/DEVELOPMENT ALONG OUTFLOW MAKING IT INTO OUR AREA LATE TODAY INTO THIS EVENING. WHICH SEEMS POSSIBLE GIVEN THE EXPECTED NOCTURNAL RECOVERY OF DEWPOINTS AND RESULTANT CONTINUATION OF DECENT INSTABILITY. THUS... HAVE INCREASED POPS ACROSS THE NORTH/NORTHWESTERN HALF OF THE CWA FOR LATE TODAY INTO THE EVENING... WITH THE CONVECTION POSSIBLY LINGERING INTO THE EARLY MORNING HOURS OF WEDNESDAY. IF WE DO SEE SOME OF THIS ACTIVITY MAKING IT INTO OUR AREA EXPECT WE COULD SEE SOME ADDITIONAL STRONG TO SEVERE STORMS... WITH THE MAIN THREAT FROM DAMAGING WINDS. EXPECT THE ACTUAL COLD FRONT TO SINK SOUTHWARD AND INTO THE AREA NEAR 12Z WEDNESDAY. HOWEVER... EXPECT OVERNIGHT LOWS SHOULD REMAIN QUITE UNCOMFORTABLE... GENERALLY RANGING FROM THE LOWER TO UPPER 70S. -77 && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 320 AM TUESDAY... THE LATEST GFS AND ECMWF ARE IN GENERAL AGREEMENT ON SHOWING THE SURFACE FRONT SETTLE SOUTH AND EASTWARD INTO SOUTHEASTERN PORTIONS OF CENTRAL NC. THUS... EXPECT THE BEST CHANCE OF SHOWERS AND STORMS WEDNESDAY AFTERNOON AND EVENING WILL BE ACROSS THE COASTAL PLAIN AND SANDHILLS... GENERALLY SOUTH AND EAST OF RALEIGH. HIGH TEMPS ON WEDNESDAY ARE EXPECTED TO RANGE FROM THE LOWER 90S/NEAR 90 NORTH TO THE MID TO UPPER 90S SOUTH. OVERNIGHT LOWS WEDNESDAY NIGHT SHOULD RANGE FROM NEAR 70 NORTH TO THE MID 70S SOUTHEAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 645 AM TUESDAY... VFR CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE 24 HOUR TAF PERIOD. MID LEVEL HIGH PRESSURE WILL CONTINUE TO EXTEND INTO CENTRAL NC FROM THE WEST... HELPING TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS CENTRAL NC FOR THE MOST PART TODAY AND THIS EVENING. HOWEVER... A WEAK DISTURBANCE WILL SLOWLY TRACK ACROSS THE AREA THIS MORNING. THIS DISTURBANCE IS EXPECTED TO BE LOCATED NEAR THE SOUTHEASTERN/FAR EASTERN PORTION OF THE AREA BY THIS AFTERNOON... WHEN IT MAY HELP TO PRODUCE SOME SHOWERS AND STORMS. KFAY WOULD STAND THE BEST CHANCE OF SEEING ANY CONVECTIVE DEVELOPMENT FROM THIS FEATURE. HOWEVER... CONFIDENCE CONTINUES TO BE TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. OTHERWISE... DRY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE INTO EARLY THIS EVENING. A CONVECTIVE LINE ASSOCIATED WITH UPSTREAM CONVECTION ORIGINATING NEAR A SOUTH/SOUTHEASTWARD SINKING COLD FRONT (CURRENTLY LOCATED FROM THE PLAINS INTO THE GREAT LAKES) THIS AFTERNOON MAY SINK SOUTHWARD INTO OUR AREA THIS EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY (WELL AHEAD OF THE FRONT). NOT OVERLY CONFIDENT ON THE TIMING... BUT FEEL WE SHOULD SEE AT LEAST SOME SCATTERED SHOWERS AND STORMS ACROSS THE NORTHERN HALF OF CENTRAL NC BY THIS EVENING. THUS... HAVE ELECTED TO GO WITH A PROB30 GROUP FOR KGSO/KINT FOR NOW. ANY CONVECTION WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS... LIGHTNING... AND SUB-VFR CONDITIONS. THE AFOREMENTIONED FRONT IS EXPECTED TO SINK SOUTHWARD AND INTO CENTRAL NC LATE TONIGHT... WITH WINDS BECOMING NORTHWESTERLY TO NORTHERNLY BEHIND THE FRONT. OUTLOOK: THE ABOVE MENTION COLD FRONT IS NOW EXPECTED TO STALL ACROSS SOUTHERN AND EASTERN PORTIONS OF THE AREA (THIS IS WHERE THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE ON WEDNESDAY). AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND (POSSIBLY SINKING TO THE SOUTH OF THE AREA ON SUNDAY). SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...ELLIS/77 SHORT TERM...77 LONG TERM...WSS AVIATION...77/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1002 AM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...BECOME STATIONARY AND LINGER IN THE AREA THROUGH THE WEEKEND. IT WILL FINALLY MOVE OFF THE COAST EARLY NEXT WEEK. && .NEAR TERM /TODAY/... AS OF 10 AM TUE...HEAT AND HUMIDITY CONTINUES TODAY...WITH BERMUDA HIGH EXTENDING OVER THE AREA FROM OFFSHORE AND TROUGHING INLAND. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 20-22C SUPPORT HIGHS IN THE LOW TO UPPER 90S. HOT TEMPS COMBINED WITH DEWPOINTS IN THE 70S WILL AGAIN RESULT IN ADV CRITERIA. HEAT ADVISORY CONTINUES ALL COUNTIES EXCEPT OUTER BANKS HYDE...WITH HEAT INDEX VALUES 105-110 THIS AFTERNOON. ISOLATED TO SCATTERED SEABREEZE SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON...PER NSSL WRF AND HRRR. EXPECT MOST CONVECTION TO WANE WITH LOSS OF HEATING EARLY THIS EVENING. THEN COULD SEE ADDITIONAL CONVECTION MOVE INTO THE NORTHERN TIER FROM THE NW AHEAD OF THE APPROACHING FRONTAL BOUNDARY. NSSL WRF AND HRRR SHOW A LINE MOVING IN BTWN 00-06Z TONIGHT...THOUGH WEAKENING AS IT MOVES SE INTO NE NC. AN ISOLATED STRONG TSTM WITH GUSTY WINDS WILL BE POSSIBLE THIS AFTERNOON AND EVENING. && .SHORT TERM /TONIGHT/... AS OF 345 AM TUE...AFTERNOON CONVECTION WILL DISSIPATE EARLY EVENING WITH LOSS OF DAYTIME HEATING. FRONTAL BOUNDARY WILL APPROACH FROM THE NORTHWEST OVERNIGHT AND HAVE REINTRODUCED 20-30% POPS AFTER 06Z. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 345 AM TUE...A GRADUAL PATTERN CHANGE IS EXPECTED BY MID/LATE WEEK AS THE HOT AND HUMID WEATHER IS REPLACED BY A BETTER CHANCE OF PRECIPITATION. WEDNESDAY/WEDNESDAY NIGHT...UPPER RIDGE WILL CONTINUE TO BE IN CONTROL FOR MUCH OF WEDNESDAY AND WITH HIGH TEMPERATURES AGAIN WELL INTO THE 90S OVER OUR SOUTHWESTERN ZONES...WILL LIKELY SEE HEAT INDICES IN THE 105-110 DEGREE RANGE AGAIN. AS A WEAK BACK DOOR FRONT DROPS SOUTH INTO OUR NORTHEASTERN COUNTIES LATE WEDNESDAY INTO WEDNESDAY NIGHT...EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS...HIGHEST NORTHEAST AREAS. THURSDAY/THURSDAY NIGHT...UPPER HEIGHTS FALL ON THURSDAY AS THE FRONTAL BOUNDARY SURGES BACK NORTH. WITH GOOD INSTABILITY...EXPECT A CHANCE OF THUNDERSTORMS AGAIN THURSDAY AFTERNOON INTO THURSDAY NIGHT. WITH MORE CLOUD COVER...TEMPERATURES WILL BE A DEGREE OR TWO COOLER...BUT WITH HIGH DEWPOINTS LINGERING...WILL STILL LIKELY SEE SOME HEAT INDEX VALUES AROUND 100 DEGREES. FRIDAY THROUGH SUNDAY...THE COMBINATION OF A STALLED FRONTAL BOUNDARY NEAR OR JUST NORTH OF THE CWA AND A CLOSED LOW FORMING OVER THE GREAT LAKES WILL LEAD TO A WETTER PATTERN FOR THE WEEKEND. MID-LEVEL TROUGH WILL DIG TO THE SOUTH AND EAST WITH TIME THROUGH THE WEEKEND TAPPING A GOOD FEED OF GULF MOISTURE. WILL CONTINUE PREVIOUS FORECAST TREND OF HIGH CHANCE POPS FRIDAY INTO SUNDAY. GUIDANCE SHOWING PRECIPITABLE WATER IN THE 2.0 TO 2.25 INCH RANGE SATURDAY INTO SUNDAY...SO SOME MUCH-NEEDED HEAVIER RAINFALL WILL BE POSSIBLE. HIGH TEMPERATURES WILL FALL INTO THE UPPER 80S OVER THE WEEKEND IN MANY SPOTS DUE TO MORE CLOUD COVER AND PRECIPITATION WITH LOWS IN THE LOW/MID 70S WITH MORE RAIN- COOLED AIR. MONDAY...AS THE UPPER LOW LIFTS OUT TO THE NORTHEAST...EXPECT DOWNSLOPING FLOW TO DRY THINGS OUT FOR EARLY NEXT WEEK. TEMPERATURES SHOULD BE NEAR CLIMATOLOGY. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... SHORT TERM /THROUGH TONIGHT/... AS OF 7 AM TUE...PATCHY MVFR FOG THIS MORNING WILL BURN OFF QUICKLY AFTER SUNRISE. VFR CONDITIONS EXPECTED THROUGH THE PERIOD OUTSIDE OF CONVECTION. LITTLE CHANGE IN THE AIRMASS AND COULD SEE PATCHY MVFR FOG DEVELOP TOWARD EARLY MORNING AT ALL SITES. SOUTHWEST WIND PERSISTS THROUGH THE PERIOD. WINDS COULD GUST TO 15-20 KTS THIS AFTERNOON WITH ISOLATED AFTERNOON/EVENING THUNDERSTORMS AT ALL 4 TERMINALS. FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST TONIGHT SO ISOLATED CONVECTION STILL POSSIBLE OVERNIGHT TUESDAY INTO EARLY WEDNESDAY. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...VFR CONDITIONS WILL PREVAIL WEDNESDAY...BUT WILL BEGIN TO SEE MORE FREQUENT SUB-VFR CONDITIONS THURSDAY INTO THE WEEKEND...ESPECIALLY FRIDAY/SATURDAY AS PRECIPITATION COVERAGE INCREASES. WILL ALSO SEE SOME AREAS OF MVFR CEILINGS AND VSBYS WITH LATE NIGHT STRATUS AND FOG IN AREAS WHERE RAIN OCCURS LATE IN THE WEEK. && .MARINE... SHORT TERM /THROUGH TONIGHT/... AS OF 10 AM TUE...SOUTHWEST FLOW CONTINUES IN THE SHORT TERM WITH THE BERMUDA HIGH IN PLACE. LATEST OBS SHOW SW WINDS 10-15KT AND SEAS 2-4FT. COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TONIGHT TIGHTENING THE PRESSURE GRADIENT...WITH WINDS INCREASING TO 15-25KT ACROSS MOST OF THE WATERS AND SOUNDS. SCA UP FOR PAMLICO SOUND AND WATERS SOUTH OF OREGON INLET...FOR GUSTY WINDS AND BUILDING SEAS THIS AFTERNOON INTO EARLY WED MORNING. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...SOME GUSTY SW WINDS TO BEGIN THE DAY ON WEDNESDAY BUT THE GRADIENT RELAXES THROUGH THURSDAY WITH GENERALLY S/SW WINDS AT 10 KNOTS OR LESS. WITH A PERSISTENT LOW INLAND AND STRONG BERMUDA RIDGE OFFSHORE...THE GRADIENT TIGHTENS THURSDAY NIGHT THROUGH SATURDAY AS A STRONG UPPER LEVEL SYSTEMS MOVES ACROSS THE MID-ATLANTIC AND SOUTHEAST. WILL LIKELY SEE SW WINDS INCREASE TO 15 TO 20 KNOTS THURSDAY NIGHT AND FRIDAY AND UP TO 20 TO 25 KNOTS ON SATURDAY. PER LATEST WAVE MODELS...SEAS BUILDS TO 6 FEET OR GREATER FOR FRIDAY INTO SATURDAY. && .CLIMATE... RECORD HIGH TEMPERATURES TUESDAY: 6/23 LOCATION-----TEMP/YEAR--NOTES NEW BERN 98/1988 (KEWN ASOS) HATTERAS 88/1996 (KHSE ASOS) GREENVILLE 100/1933 (COOP - NOT KPGV ASOS) MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS) KINSTON 102/1911 (COOP - NOT KISO ASOS) JACKSONVILLE 99/2010 (KNCA AWOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047- 079>081-090>095-098-103. MARINE...SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 4 AM EDT WEDNESDAY FOR AMZ135. SMALL CRAFT ADVISORY FROM 2 PM THIS AFTERNOON TO 10 AM EDT WEDNESDAY FOR AMZ152-154-156. SMALL CRAFT ADVISORY FROM 2 AM TO 8 AM EDT WEDNESDAY FOR AMZ158. && $$ SYNOPSIS...HSA NEAR TERM...CQD/HSA SHORT TERM...HSA LONG TERM...CTC AVIATION...CTC/HSA MARINE...CTC/CQD/HSA CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS RALEIGH NC
646 AM EDT TUE JUN 23 2015 .SYNOPSIS...AN AREA OF HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS ACROSS CENTRAL NC THROUGH FRIDAY. THE HIGH PRESSURE SYSTEM WILL DIMINISH...REPLACED BY AN AREA OF LOW PRESSURE WHICH WILL CAUSE UNSETTLED WEATHER ACROSS THE REGION THIS WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 310 AM TUESDAY... MID LEVEL HEIGHTS WILL INCREASE A BIT MORE TODAY... WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 7 TO 8 METERS HIGHER TODAY. THUS... GIVEN SIMILAR CONDITIONS EXPECT WE SHOULD SEE HIGH TEMPS GENERALLY 2-3 DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS. THIS SHOULD RESULT IN HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES ACROSS THE AREA. THIS COMBINED WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA SHOULD RESULT IN SEVERAL HOURS OF HEAT INDEX VALUES THIS AFTERNOON OF AROUND 105 DEGREES OR HIGHER. THUS... CURRENT HEAT ADVISORY LOOKS GOOD WITH NO CHANGES PLANNED AT THIS TIME. IN ADDITION TO THE HEAT... WE MAY SEE SOME AFTERNOON SHOWERS AND STORMS DEVELOP ALONG A REMNANT OUTFLOW AND MCV THAT IS CURRENTLY SINKING SOUTH AND EASTWARD INTO THE FA. THE LATEST RAP SHOWS THIS FEATURE SLOWLY SHIFTING SOUTH AND EASTWARD ACROSS CENTRAL NC THIS MORNING... WITH POSSIBLY A FEW WEAK SHOWERS DEVELOPING ALONG IT (NOTHING CURRENTLY ON RADAR). HOWEVER... AS THE FEATURE SHIFTS EASTWARD ACROSS THE AREA LATER TODAY... THINK WE MAY SEE SOME DEVELOPMENT ACROSS OUR SOUTHEASTERN/EASTERN COUNTIES... WHICH IS LOOSELY SHOWN BY SOME OF THE HIGH-RES GUIDANCES. GIVEN MODERATE INSTABILITY (IF WE INDEED GET SOME STORMS TO DEVELOP) WE COULD SEE A FEW STRONG TO PERHAPS SEVERE STORMS... MAINLY PULSE IN NATURE GIVEN CONTINUED WEAK DEEP LAYER SHEAR. THE NEXT FEATURE OF INTERESTED TODAY INTO THIS EVENING WILL BE THE APPROACH OF A COLD FRONT AND A CLUSTER OR LINE OF SHOWERS AND STORMS IN ADVANCE OF THE FRONT. SOME OF THE HI-RES (CAM`S) GUIDANCES SHOWS THIS LINE/DEVELOPMENT ALONG OUTFLOW MAKING IT INTO OUR AREA LATE TODAY INTO THIS EVENING. WHICH SEEMS POSSIBLE GIVEN THE EXPECTED NOCTURNAL RECOVERY OF DEWPOINTS AND RESULTANT CONTINUATION OF DECENT INSTABILITY. THUS... HAVE INCREASED POPS ACROSS THE NORTH/NORTHWESTERN HALF OF THE CWA FOR LATE TODAY INTO THE EVENING... WITH THE CONVECTION POSSIBLY LINGERING INTO THE EARLY MORNING HOURS OF WEDNESDAY. IF WE DO SEE SOME OF THIS ACTIVITY MAKING IT INTO OUR AREA EXPECT WE COULD SEE SOME ADDITIONAL STRONG TO SEVERE STORMS... WITH THE MAIN THREAT FROM DAMAGING WINDS. EXPECT THE ACTUAL COLD FRONT TO SINK SOUTHWARD AND INTO THE AREA NEAR 12Z WEDNESDAY. HOWEVER... EXPECT OVERNIGHT LOWS SHOULD REMAIN QUITE UNCOMFORTABLE... GENERALLY RANGING FROM THE LOWER TO UPPER 70S. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 320 AM TUESDAY... THE LATEST GFS AND ECMWF ARE IN GENERAL AGREEMENT ON SHOWING THE SURFACE FRONT SETTLE SOUTH AND EASTWARD INTO SOUTHEASTERN PORTIONS OF CENTRAL NC. THUS... EXPECT THE BEST CHANCE OF SHOWERS AND STORMS WEDNESDAY AFTERNOON AND EVENING WILL BE ACROSS THE COASTAL PLAIN AND SANDHILLS... GENERALLY SOUTH AND EAST OF RALEIGH. HIGH TEMPS ON WEDNESDAY ARE EXPECTED TO RANGE FROM THE LOWER 90S/NEAR 90 NORTH TO THE MID TO UPPER 90S SOUTH. OVERNIGHT LOWS WEDNESDAY NIGHT SHOULD RANGE FROM NEAR 70 NORTH TO THE MID 70S SOUTHEAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 645 AM TUESDAY... VFR CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE FOR THE 24 HOUR TAF PERIOD. MID LEVEL HIGH PRESSURE WILL CONTINUE TO EXTEND INTO CENTRAL NC FROM THE WEST... HELPING TO SUPPRESS CONVECTIVE DEVELOPMENT ACROSS CENTRAL NC FOR THE MOST PART TODAY AND THIS EVENING. HOWEVER... A WEAK DISTURBANCE WILL SLOWLY TRACK ACROSS THE AREA THIS MORNING. THIS DISTURBANCE IS EXPECTED TO BE LOCATED NEAR THE SOUTHEASTERN/FAR EASTERN PORTION OF THE AREA BY THIS AFTERNOON... WHEN IT MAY HELP TO PRODUCE SOME SHOWERS AND STORMS. KFAY WOULD STAND THE BEST CHANCE OF SEEING ANY CONVECTIVE DEVELOPMENT FROM THIS FEATURE. HOWEVER... CONFIDENCE CONTINUES TO BE TOO LOW TO INCLUDE IN THE TAF AT THIS TIME. OTHERWISE... DRY CONDITIONS ARE GENERALLY EXPECTED TO CONTINUE INTO EARLY THIS EVENING. A CONVECTIVE LINE ASSOCIATED WITH UPSTREAM CONVECTION ORIGINATING NEAR A SOUTH/SOUTHEASTWARD SINKING COLD FRONT (CURRENTLY LOCATED FROM THE PLAINS INTO THE GREAT LAKES) THIS AFTERNOON MAY SINK SOUTHWARD INTO OUR AREA THIS EVENING INTO THE EARLY MORNING HOURS OF WEDNESDAY (WELL AHEAD OF THE FRONT). NOT OVERLY CONFIDENT ON THE TIMING... BUT FEEL WE SHOULD SEE AT LEAST SOME SCATTERED SHOWERS AND STORMS ACROSS THE NORTHERN HALF OF CENTRAL NC BY THIS EVENING. THUS... HAVE ELECTED TO GO WITH A PROB30 GROUP FOR KGSO/KINT FOR NOW. ANY CONVECTION WILL HAVE THE POTENTIAL TO PRODUCE GUSTY WINDS... LIGHTNING... AND SUB-VFR CONDITIONS. THE AFOREMENTIONED FRONT IS EXPECTED TO SINK SOUTHWARD AND INTO CENTRAL NC LATE TONIGHT... WITH WINDS BECOMING NORTHWESTERLY TO NORTHERNLY BEHIND THE FRONT. OUTLOOK: THE ABOVE MENTION COLD FRONT IS NOW EXPECTED TO STALL ACROSS SOUTHERN AND EASTERN PORTIONS OF THE AREA (THIS IS WHERE THE BEST CHANCE FOR SHOWERS AND STORMS WILL BE ON WEDNESDAY). AFTER THE FRONT BRIEFLY RETREATS NORTH OF OUR AREA ON THU...THE PROBABILITY OF SHOWERS AND STORMS WILL FURTHER INCREASE WHEN THE FRONT SETTLES SOUTH AND STALLS OVER NC FRI THROUGH THE WEEKEND (POSSIBLY SINKING TO THE SOUTH OF THE AREA ON SUNDAY). SOME SUB-VFR CEILINGS EVEN OUTSIDE OF CONVECTION WILL ALSO BE POSSIBLE AT THAT TIME. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...77 SHORT TERM...77 LONG TERM...WSS AVIATION...77/26 CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1118 AM EDT TUE JUN 23 2015 .SYNOPSIS... SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL PENNSYLVANIA TODAY. FAIR AND DRY WEATHER IS EXPECTED ON WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WILL COOLER TEMPERATURES. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... 15Z...COORDINATED WITH SPC ON NEW SEVERE TSTM WATCH #342. THIS WATCH COVERS THE SOUTH-CENTRAL 2/3RDS OF THE CWA AND IS IN EFFECT UNTIL 7PM EDT/23Z. A POTENT SHORT-WAVE TROUGH WILL PROGRESS FROM THE ONTARIO-QUEBEC BORDER TOWARD THE CANADIAN MARITIMES WITH A CORRIDOR OF WEAK HEIGHT FALLS OVERSPREADING THE NERN U.S. LATER TODAY INTO TONIGHT. AT THE SURFACE...THE COLD FRONT RELATED TO THE ERN CANADA TROUGH WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. CONSIDERABLE EARLY MORNING CLOUDS/PCPN SUGGEST SOME DEGREE OF LOWER CONFIDENCE IN AIRMASS RECOVERY/INSTABILITY THAT WILL OCCUR AHEAD OF THE COLD FRONT THIS AFTERNOON. THAT SAID...RADAR TRENDS CONTINUE TO INDICATE INCREASING STORM INTENSITIES UPSTREAM OVER WRN PA/PBZ CWA. GENERAL THINKING AMONG THE LOCAL OFFICE AND SPC IS THAT STORMS SHOULD EVOLVE/DEVELOP ESE FROM THE I-80 CORRIDOR. THE LATEST HRRR LARGELY AGREES WITH STORMS EXITING FAR SRN/SERN PA AROUND 23Z. THE COVERAGE AND INTENSITY OF THE STORMS WILL BE PREDICATED ON THE AMOUNT OF DESTABILIZATION THAT CAN OCCUR. THE PRIMARY SEVERE WX RISK WILL BE DAMAGING WINDS WITH ATTENDANT RISK FOR A FEW ROTATING STORMS CAPABLE OF PRODUCING AN ISOLATED TORNADO AS WELL AS LARGE HAIL. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... COULD BE LINGERING ACTIVITY ALONG MASON/DIXON LINE EARLY THIS EVE...BUT COLD FRONT PROGRESSING SOUTHWARD WILL END CONVECTION BY SUNSET. COOLER AND NOTICEABLY DRIER AIR PUSHES IN BEHIND THE FRONT...WITH NORTHERN SECTIONS SLIPPING INTO THE LOWER/MID 50S TONIGHT - A GOOD 15-20F COOLER THAN THIS MORNING. DRIER AIR TAKES A BIT LONGER TO WORK INTO THE SOUTH...WITH LOWS HANGING IN THE 60S. PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE NORTHERN U.S. THROUGH FRI AND INTO THE WEEKEND. FRONTAL BOUNDARY SETTLES OVER MID ATLANTIC REGION MIDWEEK...WITH SLIGHTLY DRIER AND COOLER AIR. WEAK SYSTEM MOVING SOUTH OF THE AREA ON THU AND FRIDAY WILL BRING SOME SHOWERS TO THE AREA. SIMILAR TO LAST THU AND FRIDAY. MORE SHOWERS FOR THE WEEKEND INTO MONDAY...AS LONGWAVE TROUGH MOVES TOWARD THE EAST COAST. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... BEEN UPDATING TAFS FOR LINES AND CLUSTERS OF STORMS. WILL BE DOING THE SAME FOR THE 15Z TAF PACKAGE. STORMS MOVING EAST AT FAST CLIP. MAIN THREAT WILL BE GUSTY WINDS. SHOWERS AND STORMS SHOULD TAPER OFF FROM NW TO SE BY LATE AFT. OUTLOOK... WED...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. THU-SAT...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...RXR NEAR TERM...STEINBUGL SHORT TERM...RXR LONG TERM...MARTIN AVIATION...ROSS/CERU/MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1055 AM EDT TUE JUN 23 2015 .SYNOPSIS... SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL PENNSYLVANIA TODAY. FAIR AND DRY WEATHER IS EXPECTED ON WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WILL COOLER TEMPERATURES. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... 15Z...COORDINATED WITH SPC ON NEW SEVERE TSTM WATCH #342. THIS WATCH COVERS THE SOUTH-CENTRAL 2/3RDS OF THE CWA AND IS IN EFFECT UNTIL 7PM EDT/23Z. A POTENT SHORT-WAVE TROUGH WILL PROGRESS FROM THE ONTARIO-QUEBEC BORDER TOWARD THE CANADIAN MARITIMES WITH A CORRIDOR OF WEAK HEIGHT FALLS OVERSPREADING THE NERN U.S. LATER TODAY INTO TONIGHT. AT THE SURFACE...THE COLD FRONT RELATED TO THE ERN CANADA TROUGH WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. CONSIDERABLE EARLY MORNING CLOUDS/PCPN SUGGEST SOME DEGREE OF LOWER CONFIDENCE IN AIRMASS RECOVERY/INSTABILITY THAT WILL OCCUR AHEAD OF THE COLD FRONT THIS AFTERNOON. THAT SAID...RADAR TRENDS CONTINUE TO INDICATE INCREASING STORM INTENSITIES UPSTREAM OVER WRN PA/PBZ CWA. GENERAL THINKING AMONG THE LOCAL OFFICE AND SPC IS THAT STORMS SHOULD EVOLVE/DEVELOP ESE FROM THE I-80 CORRIDOR. THE LATEST HRRR LARGELY AGREES WITH STORMS EXITING FAR SRN/SERN PA AROUND 23Z. THE COVERAGE AND INTENSITY OF THE STORMS WILL BE PREDICATED ON THE AMOUNT OF DESTABILIZATION THAT CAN OCCUR. THE PRIMARY SEVERE WX RISK WILL BE DAMAGING WINDS WITH ATTENDANT RISK FOR A FEW ROTATING STORMS CAPABLE OF PRODUCING AN ISOLATED TORNADO AS WELL AS LARGE HAIL. && .SHORT TERM /7 PM THIS EVENING THROUGH THURSDAY/... COULD BE LINGERING ACTIVITY ALONG MASON/DIXON LINE EARLY THIS EVE...BUT COLD FRONT PROGRESSING SOUTHWARD WILL END CONVECTION BY SUNSET. COOLER AND NOTICEABLY DRIER AIR PUSHES IN BEHIND THE FRONT...WITH NORTHERN SECTIONS SLIPPING INTO THE LOWER/MID 50S TONIGHT - A GOOD 15-20F COOLER THAN THIS MORNING. DRIER AIR TAKES A BIT LONGER TO WORK INTO THE SOUTH...WITH LOWS HANGING IN THE 60S. PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... FAST ZONAL FLOW WILL BE THE PERSISTENT SYNOPTIC FEATURE ACROSS THE NORTHERN U.S. THROUGH FRI AND INTO THE WEEKEND. FRONTAL BOUNDARY SETTLES OVER MID ATLANTIC REGION MIDWEEK...WITH SLIGHTLY DRIER AND COOLER AIR. WEAK SYSTEM MOVING SOUTH OF THE AREA ON THU AND FRIDAY WILL BRING SOME SHOWERS TO THE AREA. SIMILAR TO LAST THU AND FRIDAY. MORE SHOWERS FOR THE WEEKEND INTO MONDAY...AS LONGWAVE TROUGH MOVES TOWARD THE EAST COAST. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... 12Z TAFS SENT. LINE OF SEVERE STORMS OVER NORTH CENTRAL PA. COMBINATION OF FAST MOVING STORMS AND LOW LEVEL JET RESULTING IN WIND DAMAGE. EXPECT LINE TO CONTINUE TO WORK EASTWARD THIS MORNING. MODELS HAVE SOUTHERN AREAS GETTING STORMS THIS AFT. OUTLOOK... WED-THU...GENERALLY VFR AREAS AM MVFR IN FOG/HAZE. FRI-SAT...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...STEINBUGL SHORT TERM...RXR LONGTERM...MARTIN AVIATION...ROSS/CERU/MARTIN
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
947 AM EDT TUE JUN 23 2015 .SYNOPSIS... A WEAK COOL FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND PASS SOUTH THROUGH THE REGION OVERNIGHT INTO EARLY WEDNESDAY. DRIER HIGH PRESSURE FOLLOWS THE FRONT WEDNESDAY INTO THURSDAY BEFORE MOISTURE RETURNS BACK NORTH BY THE END OF THE WEEK. ANOTHER FRONTAL SYSTEM WILL DIP SOUTH INTO THE AREA OVER THE WEEKEND AND STALL...BRINGING BETTER CHANCES OF SHOWERS AND STORMS ALONG WITH COOLER TEMPERATURES SATURDAY INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 945 AM EDT TUESDAY... THE LATEST FORECAST NEEDS NO MAJOR CHANGES AT THIS TIME. TIMING OF CONVECTION STILL LOOKS MOST PROBABLE STARTING AROUND THE MID- AFTERNOON AND ONWARD. HOT CONDITIONS STILL ARE LIKELY WITH NEAR RECORD HIGH TEMPERATURES FOR PARTS OF THE REGION. HAVE MADE MINOR TWEAKS TO THE HOURLY TEMPERATURE...DEW POINT...AND SKY COVER THROUGH THE EARLY AFTERNOON BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT TWO TO THREE HOURS. AS OF 150 AM EDT TUESDAY... AGAIN LOOKS TO BE THE HOTTEST DAY OF THE YEAR SO FAR THIS AFTERNOON WITH 85H TEMPS PUSHING +22-23C AIDED BY WESTERLY DOWNSLOPING AND COMPRESSION AHEAD OF THE FRONT APPROACHING FROM THE NORTH. THIS COMBINED WITH GOOD HEATING SHOULD PUSH SOME SPOTS TO NEAR 100 OUT EAST WITH EVEN A FEW LOW 90S MOUNTAINS. HOWEVER STILL APPEARS ENOUGH MIXING OUT OF DEWPOINTS LATER THIS AFTERNOON TO KEEP HEAT INDEX VALUES JUST BELOW CRITERIA. THUS WILL MENTION IN THE HWO BUT NOT HOIST ANY ADVISORY HEADLINES AT THIS POINT. OTHER BIGGER CONCERN WITH THE POTENTIAL STRONG TO SEVERE STORM THREAT AS CONVECTION LINES UP WITH THE PRE-FRONTAL TYPE OUTFLOW JUST AHEAD OF THE BOUNDARY HEADING IN FROM THE NW LATER ON. MODELS TENDING TO DEVELOP AT LEAST A BROKEN LINE JUST NW OF THE CWA BY MID AFTERNOON AND THEN SHIFT IT SE INTO HIGH INSTABILITY/DCAPES INCLUDING STEEP LAPSES AS THE FRONT JUMPS OUT TO THE LEE TROUGH. HOWEVER GUIDANCE DIFFERS ON HOW THIS BAND OF CONVECTION INTERACTS WITH THE DEEP...WELL MIXED WESTERLY FLOW REGIME WITH SOME SPLITTING ALONG THE BLUE RIDGE...AND OTHERS PROGRESSING ACROSS WHILE STRENGTHENING IN THE PIEDMONT AND OUT WEST. IF SLOWER... SIMILAR TO THE LATEST ENSEMBLES COULD SEE A LINE SWING THROUGH MUCH OF THE NORTH/NW CWA BY EARLY EVENING BEFORE SPLITTING IN TWO AS SUPPORTED BY THE HRRR WITH BEST COVERAGE NE WHERE FARTHER REMOVED FROM THE DOWNSLOPE...AND OVER THE FAR WEST PER CONVERGENCE. GIVEN SO MUCH WEST WIND AND NVA OVER THE REGION FOR MUCH OF THE DAY...TRENDED SLOWER WITH BRIEF LIKELY POPS FAR NW/NE...AND HIGHER CHANCES ELSW EAST OF THE BLUE RIDGE WHERE THE LOW LEVEL FLOW DOES BACK LATE. ALSO HIGHER CHANCES SE WEST VA SOUTH ALONG THE I-77 CORRIDOR WHERE OUTFLOW COULD SPARK SOME SHALLOW CONVECTION EARLY ON. OTRW APPEARS LOWEST POPS 20/30S NEW RIVER/ROANOKE VALLEYS PENDING TIMING AND DEGREE OF MIXING INTO EARLY EVENING. ALTHOUGH STRONGER WINDS ALOFT STAY TO THE NORTH...UNDIRECTIONAL FLOW COULD ALLOW FOR MULTICELL CLUSTERS/BANDS MAKING FOR DECENT DAMAGING WIND POTENTIAL IN THIS ENVIRONMENT IF STORMS CAN ORGANIZE. ADDITIONAL STRONGER STORMS MAY LINGER OVER THE SOUTH/SE THIS EVENING AND PERHAPS PERSIST IN SPOTS OVER THE FAR WEST/SW OVERNIGHT AS THE FRONT SAGS SOUTH BUT STALLS OUT CROSSING THE WEST. HOWEVER THINKING LOSS OF HEATING SHOULD PRECLUDE MUCH COVERAGE AFTER MIDNIGHT ESPCLY IF A LINE SWINGS THROUGH OR SPLITS SO ONLY LEAVING IN ISOLATED COVERAGE SOUTHERN/SW SECTIONS LATE. OTRW SOME CLEARING LIKELY IN ALL EXCEPT THE FAR WEST/SW GIVEN WESTERLY UPSLOPE FLOW...WITH PATCHY FOG AROUND UNDER MUGGY LOWS IN THE 65-70 RANGE WEST AND 68-74 EAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 334 AM EDT TUESDAY... A COOL FRONT WILL SLIDE SOUTH AND STALL OVER THE CAROLINAS WEDNESDAY. MODELS ARE ALLOWING MORE DRY AIR THAN PREVIOUS RUNS TO ENTER THE AREA...ESPECIALLY ACROSS THE NORTH. DEW POINTS WEDNESDAY AFTERNOON COULD BE AS LOW AS THE MID 50S. NOT MUCH COOL AIR WITH THE FRONTAL PASSAGE AND WITH A HIGH SUMMER SUN AND DRY AIR...TEMPERATURES WILL WARM INTO THE 80S ACROSS THE MOUNTAINS TO THE LOWER TO MID 90S EAST. WITH THE PUNCH OF DRY AIR...THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE LOW AND ISOLATED AT BEST. A SURFACE REFLECTION ALONG THE STALL FRONT OVER THE CAROLINAS WILL EDGE NORTHWARD ON THURSDAY. THIS REFECTION WILL BRING AN INCREASE IN MOISTURE AND THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS. FOR NOW...MODELS ARE INDICATING ANY CONVECTION THURSDAY WILL BE DIURNAL...BUT WE WILL NEED TO KEEP AN EYE TO THE NORTHWEST FOR ANY COMPLEXES DEVELOPING OVER THE UPPER MIDWEST AND OHIO VALLEY. TEMPERATURES THURSDAY WILL ONCE AGAIN BE WARMER THAN NORMAL WITH MID TO UPPER 80S WEST TO LOWER TO MID 90S EAST. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... AS OF 640 AM EDT TUESDAY... OUTSIDE OF PATCHY MVFR/IFR IN FOG/STRATUS EARLY ON...EXPECTING VFR CONDITIONS TO RETURN BY MID MORNING WITH GOOD FLYING CONDITIONS CONTINUING INTO EARLY THIS AFTERNOON. THIS IN ADVANCE OF A WEAK COOL FRONT THAT WILL BE APPROACHING LATER IN THE DAY. ISOLATED SHOWERS OR STORMS MAY DEVELOP OR MOVE INTO THE KBLF-KLWB AREA AROUND 19Z/3PM. THE FRONT WILL APPROACH AND THEN CROSS THE AREA THIS EVENING AND OVERNIGHT. THIS SHOULD BRING CU BUILDUPS BY EARLY AFTERNOON WITH INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. APPEARS BEST CHANCES REMAIN OVER THE WEST AROUND KBLF/KLWB AND ACROSS THE NE AROUND KLYH WITH LESS AT KBCB/KROA DUE TO WESTERLY FLOW. KDAN MAY SEE A LINE OF STORMS CROSS THE REGION IN THE EVENING BUT WONT INCLUDE MENTION FOR NOW GIVEN UNCERTAINTY. OTRW DELAYED TIMING OF CONVECTION AN HOUR OR TWO MOST SPOTS AND KEPT MOSTLY VICINITY MENTION AT THIS POINT WITH SHOWERS INCLUDED WITHIN THE PREVAILING CONDITIONS AT KBLF/KLWB. MVFR SCTD TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS INCLUDING AREAS OF FOG LATER THIS EVENING INTO WEDNESDAY MORNING. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND MUCH OF THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS BY THURSDAY EVENING. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE TODAY. BELOW ARE THE CURRENT RECORDS FOR THE DATE. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...DS/JH SHORT TERM...RCS LONG TERM...AMS AVIATION...DS/JH/KK CLIMATE...CF EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
703 AM EDT TUE JUN 23 2015 .SYNOPSIS... A WEAK COOL FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND PASS SOUTH THROUGH THE REGION OVERNIGHT INTO EARLY WEDNESDAY. DRIER HIGH PRESSURE FOLLOWS THE FRONT WEDNESDAY INTO THURSDAY BEFORE MOISTURE RETURNS BACK NORTH BY THE END OF THE WEEK. ANOTHER FRONTAL SYSTEM WILL DIP SOUTH INTO THE AREA OVER THE WEEKEND AND STALL...BRINGING BETTER CHANCES OF SHOWERS AND STORMS ALONG WITH COOLER TEMPERATURES SATURDAY INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 150 AM EDT TUESDAY... AGAIN LOOKS TO BE THE HOTTEST DAY OF THE YEAR SO FAR THIS AFTERNOON WITH 85H TEMPS PUSHING +22-23C AIDED BY WESTERLY DOWNSLOPING AND COMPRESSION AHEAD OF THE FRONT APPROACHING FROM THE NORTH. THIS COMBINED WITH GOOD HEATING SHOULD PUSH SOME SPOTS TO NEAR 100 OUT EAST WITH EVEN A FEW LOW 90S MOUNTAINS. HOWEVER STILL APPEARS ENOUGH MIXING OUT OF DEWPOINTS LATER THIS AFTERNOON TO KEEP HEAT INDEX VALUES JUST BELOW CRITERIA. THUS WILL MENTION IN THE HWO BUT NOT HOIST ANY ADVISORY HEADLINES AT THIS POINT. OTHER BIGGER CONCERN WITH THE POTENTIAL STRONG TO SEVERE STORM THREAT AS CONVECTION LINES UP WITH THE PRE-FRONTAL TYPE OUTFLOW JUST AHEAD OF THE BOUNDARY HEADING IN FROM THE NW LATER ON. MODELS TENDING TO DEVELOP AT LEAST A BROKEN LINE JUST NW OF THE CWA BY MID AFTERNOON AND THEN SHIFT IT SE INTO HIGH INSTABILITY/DCAPES INCLUDING STEEP LAPSES AS THE FRONT JUMPS OUT TO THE LEE TROUGH. HOWEVER GUIDANCE DIFFERS ON HOW THIS BAND OF CONVECTION INTERACTS WITH THE DEEP...WELL MIXED WESTERLY FLOW REGIME WITH SOME SPLITTING ALONG THE BLUE RIDGE...AND OTHERS PROGRESSING ACROSS WHILE STRENGTHENING IN THE PIEDMONT AND OUT WEST. IF SLOWER... SIMILAR TO THE LATEST ENSEMBLES COULD SEE A LINE SWING THROUGH MUCH OF THE NORTH/NW CWA BY EARLY EVENING BEFORE SPLITTING IN TWO AS SUPPORTED BY THE HRRR WITH BEST COVERAGE NE WHERE FARTHER REMOVED FROM THE DOWNSLOPE...AND OVER THE FAR WEST PER CONVERGENCE. GIVEN SO MUCH WEST WIND AND NVA OVER THE REGION FOR MUCH OF THE DAY...TRENDED SLOWER WITH BRIEF LIKELY POPS FAR NW/NE...AND HIGHER CHANCES ELSW EAST OF THE BLUE RIDGE WHERE THE LOW LEVEL FLOW DOES BACK LATE. ALSO HIGHER CHANCES SE WEST VA SOUTH ALONG THE I-77 CORRIDOR WHERE OUTFLOW COULD SPARK SOME SHALLOW CONVECTION EARLY ON. OTRW APPEARS LOWEST POPS 20/30S NEW RIVER/ROANOKE VALLEYS PENDING TIMING AND DEGREE OF MIXING INTO EARLY EVENING. ALTHOUGH STRONGER WINDS ALOFT STAY TO THE NORTH...UNDIRECTIONAL FLOW COULD ALLOW FOR MULTICELL CLUSTERS/BANDS MAKING FOR DECENT DAMAGING WIND POTENTIAL IN THIS ENVIRONMENT IF STORMS CAN ORGANIZE. ADDITIONAL STRONGER STORMS MAY LINGER OVER THE SOUTH/SE THIS EVENING AND PERHAPS PERSIST IN SPOTS OVER THE FAR WEST/SW OVERNIGHT AS THE FRONT SAGS SOUTH BUT STALLS OUT CROSSING THE WEST. HOWEVER THINKING LOSS OF HEATING SHOULD PRECLUDE MUCH COVERAGE AFTER MIDNIGHT ESPCLY IF A LINE SWINGS THROUGH OR SPLITS SO ONLY LEAVING IN ISOLATED COVERAGE SOUTHERN/SW SECTIONS LATE. OTRW SOME CLEARING LIKELY IN ALL EXCEPT THE FAR WEST/SW GIVEN WESTERLY UPSLOPE FLOW...WITH PATCHY FOG AROUND UNDER MUGGY LOWS IN THE 65-70 RANGE WEST AND 68-74 EAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 334 AM EDT TUESDAY... A COOL FRONT WILL SLIDE SOUTH AND STALL OVER THE CAROLINAS WEDNESDAY. MODELS ARE ALLOWING MORE DRY AIR THAN PREVIOUS RUNS TO ENTER THE AREA...ESPECIALLY ACROSS THE NORTH. DEW POINTS WEDNESDAY AFTERNOON COULD BE AS LOW AS THE MID 50S. NOT MUCH COOL AIR WITH THE FRONTAL PASSAGE AND WITH A HIGH SUMMER SUN AND DRY AIR...TEMPERATURES WILL WARM INTO THE 80S ACROSS THE MOUNTAINS TO THE LOWER TO MID 90S EAST. WITH THE PUNCH OF DRY AIR...THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE LOW AND ISOLATED AT BEST. A SURFACE REFLECTION ALONG THE STALL FRONT OVER THE CAROLINAS WILL EDGE NORTHWARD ON THURSDAY. THIS REFECTION WILL BRING AN INCREASE IN MOISTURE AND THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS. FOR NOW...MODELS ARE INDICATING ANY CONVECTION THURSDAY WILL BE DIURNAL...BUT WE WILL NEED TO KEEP AN EYE TO THE NORTHWEST FOR ANY COMPLEXES DEVELOPING OVER THE UPPER MIDWEST AND OHIO VALLEY. TEMPERATURES THURSDAY WILL ONCE AGAIN BE WARMER THAN NORMAL WITH MID TO UPPER 80S WEST TO LOWER TO MID 90S EAST. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... AS OF 640 AM EDT TUESDAY... OUTSIDE OF PATCHY MVFR/IFR IN FOG/STRATUS EARLY ON...EXPECTING VFR CONDITIONS TO RETURN BY MID MORNING WITH GOOD FLYING CONDITIONS CONTINUING INTO EARLY THIS AFTERNOON. THIS IN ADVANCE OF A WEAK COOL FRONT THAT WILL BE APPROACHING LATER IN THE DAY. ISOLATED SHOWERS OR STORMS MAY DEVELOP OR MOVE INTO THE KBLF-KLWB AREA AROUND 19Z/3PM. THE FRONT WILL APPROACH AND THEN CROSS THE AREA THIS EVENING AND OVERNIGHT. THIS SHOULD BRING CU BUILDUPS BY EARLY AFTERNOON WITH INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. APPEARS BEST CHANCES REMAIN OVER THE WEST AROUND KBLF/KLWB AND ACROSS THE NE AROUND KLYH WITH LESS AT KBCB/KROA DUE TO WESTERLY FLOW. KDAN MAY SEE A LINE OF STORMS CROSS THE REGION IN THE EVENING BUT WONT INCLUDE MENTION FOR NOW GIVEN UNCERTAINTY. OTRW DELAYED TIMING OF CONVECTION AN HOUR OR TWO MOST SPOTS AND KEPT MOSTLY VICINITY MENTION AT THIS POINT WITH SHOWERS INCLUDED WITHIN THE PREVAILING CONDITIONS AT KBLF/KLWB. MVFR SCTD TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS INCLUDING AREAS OF FOG LATER THIS EVENING INTO WEDNESDAY MORNING. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND MUCH OF THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS BY THURSDAY EVENING. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE TODAY. BELOW ARE THE CURRENT RECORDS FOR THE DATE. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...JH SHORT TERM...RCS LONG TERM...AMS AVIATION...DS/JH/KK CLIMATE...CF EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
206 PM MST TUE JUN 23 2015 .SYNOPSIS...MOISTURE WILL CONTINUE TO INCREASE THIS WEEK AS MONSOON 2015 CONTINUES. EASTERN AREAS WILL BE FAVORED FOR THUNDERSTORM DEVELOPMENT THIS AFTERNOON AND EVENING. THEN EXPECT A DECENT CHANCE OF SHOWERS AND THUNDERSTORMS WEDNESDAY THROUGH THIS WEEKEND FOR MOST OF SOUTHEAST ARIZONA. AS THIS HAPPENS...DAYTIME TEMPERATURES WILL MODERATE CLOSER TO SEASONAL NORMALS BY THE END OF THE WEEK. && .DISCUSSION...CUMULUS BEGINNING TO FORM THIS AFTERNOON OVER THE HIGHER TERRAIN. ISOLD/SCT TSTORMS ARE EXPECTED IN LINE WITH HRRR AS WELL AS NAM AND VARIOUS WRF RUNS. TSTORMS OVER THE RIM WILL SHIFT SW INTO THIS EVENING WHILE TSTORMS OVER COCHISE COUNTY SHIFT WESTWARD. SURFACE DEW POINT DEPRESSIONS ARE NEAR 60 DEGREES...SINCE TEMPERATURES ARE OVER 100 AND DEW POINTS ARE IN THE 40S. THIS POINTS TO A GOOD POTENTIAL FOR SEVERE WIND GUSTS FROM STORMS THAT MAKE IT INTO THE HOT VALLEYS. IT APPEARS THAT MOST OF THIS TSTORM ACTIVITY WILL REMAIN EAST OF TUCSON BEFORE DISSIPATING BEFORE MIDNIGHT. HOWEVER...CANNOT RULE OUT A STRAY SHOWER FROM TUCSON WEST INTO THE OVERNIGHT. NO MATTER HOW FAR WEST STORMS PROGRESS TONIGHT...EASTERLY WINDS WILL USHER INCREASED MOISTURE INTO SE AZ...SETTING UP A POTENTIALLY ACTIVE DAY ON WEDNESDAY. AS MENTIONED...EXPECT INCREASED COVERAGE OF THUNDERSTORMS WEDNESDAY WITH DEVELOPMENT BY EARLY AFTERNOON. STRONG TO SEVERE THUNDERSTORM WIND GUSTS WILL AGAIN BE A LIKELY RESULT OF SOME OF TSTORMS AND BLOWING DUST WILL BE A DISTINCT POSSIBILITY IN THE I-10 CORRIDOR NW OF TUCSON. THURSDAY TSTORM ACTIVITY COULD BE FAIRLY LIMITED TO FAR SOUTHERN AREAS BUT AS HIGH PRESSURE SHIFTS NORTHWARD...INCREASED MOISTURE AND THUNDERSTORMS ARE IN THE OFFING FROM FRIDAY INTO EARLY NEXT WEEK. THE INCREASED MOISTURE SHOULD KEEP HIGH TEMPS BELOW THE LEVELS OF THE PAST SEVERAL DAYS...MORE IN LINE WITH NORMAL FOR LATE JUNE. && .AVIATION...VALID THROUGH 25/00Z. ISOLD-SCT TSRA WILL DEVELOP NEAR THE HIGH TERRAIN EAST OF KTUS AND MOVE GENERALLY TOWARDS THE SW OR WSW THROUGH 24/06Z WITH GRADUAL CLEARING AFTERWARDS. THE PRIMARY FOCUS FOR TSRA THROUGH THE REST OF TODAY SHOULD BE EAST OF ROUGHLY A KSOW-KALK-KOLS LINE...ALTHOUGH REMNANT OUTFLOWS MAY MAKE IT AS FAR NW AS KTUS. TOMORROW...GREATER COVERAGE IS EXPECTED...WITH STORMS DEVELOPING ACROSS MUCH OF SE AZ. WIND GUSTS OF 40-50 KTS WILL BE POSSIBLE IN AND NEAR THUNDERSTORMS. GUSTY NW WINDS THROUGH THE GILA VALLEY INCLUDING KSAD WILL DIMINISH AFTER SUNSET...AS EASTERLY WINDS AT 10-14KTS AND HIGHER GUSTS DEVELOP NEAR KDUG. EASTERLY BREEZES WILL THEN PREVAIL AREA-WIDE WEDNESDAY WITH A CONTINUED THREAT OF THUNDERSTORM WIND GUSTS. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...MONSOONAL MOISTURE WILL BE DIRECTED INTO SOUTHEAST ARIZONA FOR THE NEXT SEVERAL DAYS WITH THUNDERSTORM ACTIVITY RAMPING UP THROUGH THE WEEKEND. TODAY...THUNDERSTORMS WILL MAINLY BE LIMITED TO EASTERN PARTS OF THE AREA...ZONES 152...153 AND SOUTHERN 151. COVERAGE OF STORMS WILL THEN SPREAD WESTWARD EACH AFTERNOON THROUGH REST OF THE WEEK. INITIAL THREAT FROM THUNDERSTORMS WILL BE STRONG GUSTY OUTFLOWS AND POSSIBLE LIGHTNING STARTS THROUGH WEDNESDAY UNTIL MOISTURE BECOMES MORE ENTRENCHED. OTHERWISE...DIURNAL WIND TRENDS WILL BE THE RULE. BREEZY NW WINDS WILL CONTINUE THIS AFTERNOON ESPECIALLY THROUGH THE GILA VALLEY. EASTERLY WINDS WILL INCREASE THIS EVENING AND OVERNIGHT TONIGHT ESPECIALLY ACROSS EASTERN ZONES AND CONTINUE THROUGH THE DAY ON WEDNESDAY AND THURSDAY. WINDS WILL SWING BACK AROUND TO A NORTHWESTERLY DIRECTION ON FRIDAY. SATURDAY THROUGH MONDAY...WINDS WILL BE EASTERLY/SOUTHEASTERLY DURING THE AFTERNOON. && .TWC WATCHES/WARNINGS/ADVISORIES...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON PUBLIC/DROZD AVIATION/CARLAW FIRE WEATHER/FRENCH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
321 PM MDT TUE JUN 23 2015 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 154 PM MDT TUE JUN 23 2015 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY FRONT ALONG FRONT RANGE. THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY. WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR 100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A CONSERVATIVE APPROACH FOR NOW. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 318 PM MDT TUE JUN 23 2015 FORECAST PROBLEMS WILL BE CHANCES OF THUNDERSTORMS THROUGH FRIDAY. SATELLITE SHOWING A PROGRESSIVE/NEAR ZONAL FLOW FROM THE PACIFIC INTO THE WESTERN ATLANTIC. BROAD UPPER RIDGE NOW IN PLACE OVER MOST OF THE SOUTHERN HALF OF THE COUNTRY. AT JET LEVEL...MODELS START OUT FINE. AT MID LEVELS...THE CANADIAN AND GFS WERE DOING A LITTLE BETTER THAN THE NAM AND ECMWF. THE ECMWF WAS DOING A LITTLE BETTER THAN THE SREF/GFS/NAM ON THE SURFACE WIND AND PRESSURE FIELD. THE SREF/ECMWF/NAM WERE DOING A LITTLE BETTER THAN THE REST OF THE OUTPUT ON THE LOW LEVEL THERMAL FIELD. WEDNESDAY NIGHT...RIGHT REAR QUADRANT OF JET CONTINUES ACROSS THE NORTHERN HALF OF THE AREA THROUGH THE NIGHT ALTHOUGH IT WEAKENS A LITTLE LATER IN THE NIGHT. BY LATE IN THE AFTERNOON THE FRONT HAS SAGGED DOWN THROUGH ABOUT THE WHOLE AREA EXCEPT MAYBE FOR THE SOUTHERN FRINGE. MID LEVEL SHORTWAVE/LIFT MOVE AFFECT THE NORTHWEST HALF OF THE AREA THROUGH MIDDLE OF THE NIGHT BEFORE MOVING OUT OF THE NORTHERN PORTION DURING THE OVERNIGHT HOURS. SO THE NORTHWEST HALF OF THE AREA WILL HAVE THE HIGHEST POPS ESPECIALLY THE FAR WEST AND NORTH. THURSDAY/THURSDAY NIGHT... SHORTWAVE TROUGHS IN NORTHWEST FLOW IS ALWAYS A TRICKY AND POTENTIALLY ACTIVE SETUP FOR THE AREA. THERE LOOKS TO BE SOME WEAK LIFT FROM THE RIGHT REAR QUADRANT DURING THE AFTERNOON. MAIN JET LOOKS TO STAY NORTH OF THE AREA DURING THE NIGHT. THE FRONT INITIALLY STAYS CLOSE TO THE SOUTHERN PORTION OF THE AREA BEFORE MOVING EVEN FARTHER SOUTH. MULTIPLE SHORTWAVE TROUGHS MAKE AFTERNOON AND NIGHTTIME PRECIPITATION FORECAST MESSY. ONE SHORTWAVE WILL AFFECT THE SOUTHEAST PORTION OF THE AREA DURING THE AFTERNOON AS ANOTHER WAVE APPROACHES THE FAR WEST. ALSO POST FRONTAL UPSLOPE OR THE PROXIMITY OF THE BOUNDARY TO THE WESTERN PORTION OF THE AREA WILL HELP DEVELOP STORMS. SO AT THIS TIME WILL HAVE SLIGHT CHANCE TO LOW CHANCE POPS ALONG THE SOUTHEAST AND WESTERN PORTIONS OF THE AREA. FOR THE NIGHT...A DECENT BAROCLINIC ZONE LOOKS TO MOVE ACROSS IN ADVANCE OF A FEW SHORTWAVE TROUGHS. ONE SHORTWAVE TROUGH MOVES ACROSS THE SOUTHWEST PORTION WITH ANOTHER MOVING ACROSS THE NORTHERN PORTION. COMBINATION OF THE BAROCLINIC ZONE AND FAVORABLE THETA-E LAPSE RATES SHOULD ALLOW FOR A GOOD RESPONSE TO THE LIFT. SO CHANCE POPS WILL TRANSITION FROM NORTHWEST TO SOUTHEAST DURING THIS TIME. SEE THE POTENTIAL FOR THE POPS TO BE RAISED FROM THIS. AS STATED ABOVE MOST IF NOT ALL OF THE AREA WILL BE IN POST FRONTAL UPSLOPE FLOW AND LINGERING CLOUD COVER. AS A RESULT THE HIGH TEMPERATURES WILL BE COOLER. DEPENDING ON HOW LONG LOW LEVEL CLOUD COVER LASTS...TEMPERATURES MAY NEED TO BE MADE EVEN COOLER THAN WHAT IS IN THERE NOW. FRIDAY...MAIN JET REMAINS NORTH OF THE AREA. DECENT BAROCLINIC ZONE AND COLD AIR ADVECTION WILL CONTINUE TO MOVE ACROSS DURING THE DAY. SHORTWAVES WILL ROTATE THROUGH THE NORTHERLY FLOW ALOFT WITH A MODERATELY STRONG SHORTWAVE MOVING THROUGH FROM LATE IN THE MORNING THROUGH MID AFTERNOON. SO HAVE SLIGHT TO CHANCE POPS FOR NOW. COLD AIR ALOFT...POST FRONTAL SURFACE WINDS...CLOUD COVER AND PRECIPITATION WILL HELP KEEP TEMPERATURES FROM RISING TOO MUCH. TEMPERATURES LOOK TO BE COOLER THAN THE PREVIOUS DAY BUT ONCE AGAIN THE POTENTIAL IS THERE AGAIN TO HAVE TO MAKE THESE TEMPERATURES COOLER. FRIDAY NIGHT THROUGH TUESDAY...PATTERN WILL AMPLIFY THROUGH THE PERIOD WITH A RATHER STRONG/SHARP UPPER RIDGE TO OUR WEST. MODELS ARE IN GOOD AGREEMENT WITH THIS. PERIODIC SHORTWAVE TROUGHS ALONG WITH THE ASSOCIATED SURFACE FEATURES WILL MOVE THROUGH IN THE NORTHWEST TO EVENTUALLY NORTH FLOW ALOFT. HARD TO RULE OUT PRECIPITATION IN THIS PERIOD. AT THIS TIME...IT LOOKS LIKE ISOLATED AFTERNOON AND EVENING CONVECTION...MAINLY IN MY WESTERN/NORTHERN PORTIONS THROUGH THE PERIOD. THE CRH_INIT DEPICTED THIS SCENARIO NICELY AND DID NOT CHANGE THE POPS THAT I WAS GIVEN. THE ONLY TRULY DRY PERIOD LOOKS TO BE MONDAY AND MONDAY NIGHT. TEMPERATURES SHOULD NOT GET TOO HOT OR WAY ABOVE NORMAL DUE TO THE NORTHERLY FLOW ALOFT AND PERSISTENT EASTERLY SURFACE WINDS OF SOME SORT. THIS IS ALSO DEPICTED NICELY BY THE INIT AND DID NOT CHANGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1110 AM MDT TUE JUN 23 2015 VFR CONDITIONS AND DRY CONDITIONS ARE LIKELY FOR BOTH KGLD AND KMCK TERMINALS. THUNDERSTORMS MAY MOVE WITHIN THE VICINITY OF BOTH TERMINALS THIS EVENING HOWEVER CONFIDENCE IN COVERAGE IS TOO LOW TO INCLUDE MENTION. THERE IS ALSO THE POSSIBILITY FOR STRATUS OR FOG TO DEVELOP NORTH OF A FRONT THAT WILL STALL NEAR KMCK. DUE TO LACK OF MODEL CONSENSUS AND STATISTICAL GUIDANCE FAVORING VFR I LEFT MENTION OF MVFR/IFR CONDITIONS OUT OF KMCK FOR NOW. EAST TO SOUTHEAST WINDS WILL SHIFT TO THE SOUTH OVERNIGHT AS THIS FRONT LIFT NORTH AT KGLD AND THEN KMCK BY WEDNESDAY MORNING. THERE COULD BE A PERIOD OF LOW LEVEL WIND SHEER WITH DEVELOPMENT OF LLJ LATE TONIGHT THROUGH EARLY WEDNESDAY MORNING. I DECIDED TO LEAVE OUT FOR NOW AS SURFACE WINDS MAY REMAIN HIGH ENOUGH NOT TO MEET INCLUSION CRITERIA. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BULLER AVIATION...DR
AREA FORECAST DISCUSSION
NWS GOODLAND KS
155 PM MDT TUE JUN 23 2015 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 154 PM MDT TUE JUN 23 2015 EARLY AFTERNOON WV IMAGERY AND RAP H5 ANALYSIS SHOWS RIDGE STILL IN PLACE ACROSS SOUTHERN PLAINS WITH WESTERLY ZONAL FLOW ACROSS THE NORTHERN PLAINS. WEAK SHORTWAVE TROUGHS AND MONSOONAL/PACIFIC FLOW CONTINUE TO ROTATE ALONG THE WESTERN PERIPHERY OF THE RIDGE AND INTO THE CENTRAL ROCKIES. AT THE SURFACE STATIONARY FRONT HAS LIFTED TO NEAR SCOTT CITY JUST SOUTH OF OUR CWA WITH STATIONARY FRONT ALONG FRONT RANGE. THIS AFTERNOON-TONIGHT...GUIDANCE CONTINUES TO SHOW WARM FRONT LIFTING NORTH THROUGH THE AFTERNOON AND EVENING AS LEE TROUGH DEEPENS. THUNDERSTORMS HAVE ALREADY DEVELOPED ACROSS SOUTH CENTRAL COLORADO. HIGH RES GUIDANCE CONTINUES TO SHOW CAP WEAKENING ALONG THE FRONT FROM THE WEST TO THE EAST...AND THUNDERSTORMS EITHER DEVELOPING OR MOVING INTO THE SW PART OF THE CWA SPREADING NORTH AND EAST THIS EVENING. WHILE PWATS AND TD VALUES ARE IMPRESSIVE...DEEP LAYER MIXING RATIOS/MOISTURE PROFILES ARE LESS THAN FAVORABLE FOR WIDESPREAD COVERAGE LOCALLY WITHOUT ORGANIZATION INTO MORE OF A CLUSTER FROM THE WEST. SHORTWAVE TROUGH ADVERTISED TO MOVE ACROSS CWA THIS EVENING COULD HELP WITH INITIATION...SO DESPITE THE DRY LAYERS ALOFT 20 TO 30 POPS STILL SEEMS REASONABLE. VEERING SHEER PROFILES IN THE 0-3KM LAYER COULD HELP SUPERCELL POTENTIAL ASSUMING THUNDERSTORMS DEVELOP THIS AFTERNOON/EARLY EVENING ALONG WARM FRONT BEFORE LOW LEVELS STABILIZE. AS EVENING PROGRESSES PROFILES FAVOR MAINLY ELEVATED THUNDERSTORMS...AND GOOD EFFECTIVE SHEER VALUES SHOULD STILL SUPPORT LARGE HAIL/DAMAGING WIND THREAT WITH ANY ONGOING ACTIVITY. WEDNESDAY...WARM FRONT STALLS NEAR THE KS/NE BORDER EARLY WEDNESDAY MORNING WITH MOISTURE POOLING NORTH OF THIS FRONT EARLY WEDNESDAY MORNING WHEN FOG/STRATUS COULD DEVELOP. GUIDANCE STILL SHOWING A POTENTIAL BUT I AM STILL NOT SURE VIS WILL BE LOW ENOUGH TO INCLUDE MENTION IN FORECAST...SO WILL MONITOR SHORT RANGE GUIDANCE/TRENDS. FRONT SETS UP ROUGHLY THROUGH THE CENTRAL PART OF THE CWA AS SURFACE LOW SHIFTS EAST WEDNESDAY AFTERNOON...WITH NEAR 100F TEMPS SOUTH OF THIS FRONT AND IN THE 90S TO THE NW. THIS FRONT WILL ACT AS A FOCUS FOR POSSIBLY THUNDERSTORM DEVELOPMENT IN THE AFTERNOON...AGAIN AIDED BY HEIGHT FALLS FROM WEAK SHORTWAVE ROTATING INTO THE REGION FROM THE WEST. I KEPT 20 POPS CONFINED TO THE SW IN THE AFTERNOON...THOUGH DEPENDING ON CAP STRENGTH I COULD SEE A ISOLATED THUNDERSTORM FURTHER EAST. NOT A STRONG SIGNAL IN THE AFTERNOON FURTHER EAST..SO I FAVOR STICKING WITH A CONSERVATIVE APPROACH FOR NOW. .LONG TERM...(FRIDAY THROUGH MONDAY) ISSUED AT 355 AM MDT TUE JUN 23 2015 AT THE BEGINNING OF THE EXTENDED PERIOD MODELS ARE STARTING TO AMPLIFY AN UPPER LEVEL RIDGE OVER THE WESTERN U.S. AND DEEPENING AN UPPER LEVEL TROUGH OVER THE EASTERN U.S. THIS WILL SHIFT THE UPPER LEVEL FLOW TO A MORE NORTHERLY BY THE END OF THE PERIOD. MODELS ARE A LITTLE DIFFERENT IN HOW THEY HANDLE THE POSITION OF THE SURFACE BOUNDARY. SO MADE VERY LITTLE ADJUSTMENTS TO THE CRH_INIT GRIDS. LOOK FOR THE MOST ACTIVE AND WET PART OF THE PERIOD TO BE AT THE BEGINNING OF THE EXTENDED AND LAST INTO SATURDAY NIGHT. AFTER THAT EXPECT DRIER CONDITIONS AS THE RIDGE INFLUENCE THE TRI STATE AREA WITH THE DRY NORTHERLY FLOW. TEMPERATURES WILL NOT WARM UP AS MUCH DUE TO THE NORTHERLY FLOW. IT IS POSSIBLE THAT TEMPERATURES MAY NEED TO BE LOWERED A LITTLE AS WE GET CLOSER TO THIS PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1110 AM MDT TUE JUN 23 2015 VFR CONDITIONS AND DRY CONDITIONS ARE LIKELY FOR BOTH KGLD AND KMCK TERMINALS. THUNDERSTORMS MAY MOVE WITHIN THE VICINITY OF BOTH TERMINALS THIS EVENING HOWEVER CONFIDENCE IN COVERAGE IS TOO LOW TO INCLUDE MENTION. THERE IS ALSO THE POSSIBILITY FOR STRATUS OR FOG TO DEVELOP NORTH OF A FRONT THAT WILL STALL NEAR KMCK. DUE TO LACK OF MODEL CONSENSUS AND STATISTICAL GUIDANCE FAVORING VFR I LEFT MENTION OF MVFR/IFR CONDITIONS OUT OF KMCK FOR NOW. EAST TO SOUTHEAST WINDS WILL SHIFT TO THE SOUTH OVERNIGHT AS THIS FRONT LIFT NORTH AT KGLD AND THEN KMCK BY WEDNESDAY MORNING. THERE COULD BE A PERIOD OF LOW LEVEL WIND SHEER WITH DEVELOPMENT OF LLJ LATE TONIGHT THROUGH EARLY WEDNESDAY MORNING. I DECIDED TO LEAVE OUT FOR NOW AS SURFACE WINDS MAY REMAIN HIGH ENOUGH NOT TO MEET INCLUSION CRITERIA. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DR LONG TERM...BW AVIATION...DR
AREA FORECAST DISCUSSION
NWS JACKSON KY
156 PM EDT TUE JUN 23 2015 .UPDATE... ISSUED AT 156 PM EDT TUE JUN 23 2015 THE COLD FRONT CONTINUES TO LOOK MORE SHEARED OUT AS IT MOVES TOWARDS OUR CWA...AND SEEMS TO BE MOVING A BIT SLOWER RATE THAN ORIGINALLY ANTICIPATED. WHILE THERE HAS BEEN A PRETTY GOOD CAP ACROSS THE REGION...ONCE OUR CONVECTIVE TEMPERATURE IS REACHED IN THE NEXT HOUR OR SO...EXPECT WE WILL BREAK OUR CAP AND TAP INTO SOME CONVECTION AND DECENT SHEAR. RAIN SHOWERS HAVE ALREADY STARTING POPPING ACROSS NORTH CENTRAL KY OVER THE LAST FEW RADAR SCANS...SO THUNDERSTORMS WILL LIKELY BE SOON TO FOLLOW. AS SUCH...BASED ON THE OVERALL WEAKENING OF THE BOUNDARY...STILL ONLY EXPECTING ISOLATED TO SCATTERED STORMS...WITH THE BULK SUB SEVERE. STILL COULDN/T RULE OUT A FEW STRAY STRONGER STORMS HOWEVER. LOWERED POPS ALONG LMK/S CWA THROUGH THE NEXT COUPLE OF HOURS SINCE THE FRONT IS EVEN MORE SHEARED AS YOU HEAD WEST TOWARDS THEIR AREA...WITH ONLY ISOLATED CONVECTION EXPECTED THROUGH 18Z. BUT AFTER THAT...AT LEAST 30 PERCENT COVERAGE WILL BE POSSIBLE SOUTH OF THE OHIO RIVER AREA. UPDATE ISSUED AT 1041 AM EDT TUE JUN 23 2015 BASED ON THE LATEST HRRR...WHICH IS INITIALIZING VERY WELL SO FAR THIS MORNING...AS WELL AS SUPPORT FROM OTHER HI RES MODELS...WENT AHEAD AND UPDATED POPS FOR THE REMAINDER OF THE DAY. WHILE THIS DIDN/T CREATE ANY DRASTIC CHANGES...DO EXPECT OUR BEST CHANCES FOR STORMS AND SCATTERED COVERAGE TO BE CONTAINED ALONG AND THEN SOUTH OF THE OHIO RIVER THIS AFTERNOON AND INTO THIS EVENING. THIS LED TO A SLIGHT REDUCTION IN POPS THIS MORNING IN THE NORTH...REDUCING THEM DOWN TO ISOLATED...BECOMING SCATTERED ONCE STORMS DROP BELOW THE OHIO RIVER AREA. ALSO LOADED IN THE LATEST OBSERVATIONAL DATA TO MAKE SURE THE CURRENT TEMPS...DEW POINTS...AND WINDS WERE WELL REFLECTED IN THE NEAR TERM CONDITIONS. UPDATE ISSUED AT 735 AM EDT TUE JUN 23 2015 WHILE A FEW SHOWERS DID POP UP OVER TENNESSEE...NOTHING ELSE HAS BEEN NOTED WITH THE INITIAL BOUNDARY CROSSING EASTERN KENTUCKY THIS MORNING. THUS...WILL REMOVE RAIN CHANCES THIS MORNING IN FAVOR OF RAIN CHANCES WITH THE COLD FRONT THIS AFTERNOON/EVENING. HRRR/RAP CONTINUES TO SHOW SOME SCATTERED CONVECTION DEVELOPING AND APPEARS TO MOVE SOUTH MUCH FASTER THAN THE NAM. IN FACT...IF THE HI RES MODELS WORK OUT...VERY LITTLE PRECIPITATION WILL BE POSSIBLE AFTER 00Z THIS EVENING. THE LAST FEW RUNS OF THE HI RES MODELS ALSO SHOW VARYING DEGREES OF COVERAGE AND IN SOME CASES VERY LOW COVERAGE...SO ITS STILL POSSIBLE SOME AREAS WILL STAY DRY THROUGH THE DAY DESPITE THE COLD FRONTAL PASSAGE. NO CHANGES TO SEVERE THREATS AS DAMAGING WINDS WILL REMAIN POSSIBLE WITH THE STRONGEST STORMS TODAY. && .SHORT TERM...(TODAY THROUGH WEDNESDAY) ISSUED AT 310 AM EDT TUE JUN 23 2015 A COUPLE OF BOUNDARIES TO KEEP AN EYE ON TODAY. THE FIRST ONE IS CROSSING INTO CENTRAL KENTUCKY PRESENTLY AND HAS BEEN VISIBLE ON AREA RADARS. THE SECOND BOUNDARY WILL BE A COLD FRONT ACROSS THE LOWER GREAT LAKES THAT WILL SWEEP SOUTH ACROSS THE AREA LATER TODAY. IN THE IMMEDIATE SHORT TERM...FOCUS IS ON THE FIRST BOUNDARY. HRRR CONTINUES TO SHOW SOME DEVELOPMENT ALONG THE BOUNDARY POSSIBLE AS IT SHIFTS EAST ACROSS THE AREA THROUGH DAYBREAK. NOT MUCH NOTED SO FAR...AND THE RAP HAS BACKED OFF ON THE POSSIBLE CONVECTION. WILL MAINTAIN SOME SLIGHT CHANCE POPS AS THIS BOUNDARY PROGRESSES ACROSS THE AREA THIS MORNING. IT LOOKS LIKE A LULL IS EXPECTED THROUGH MUCH OF THE COMING DAY AS WE WAIT FOR THE COLD FRONT TO THE NORTH TO DROP SOUTH. THIS SHOULD HAPPEN BY 2 PM WITH CHANCES OF SHOWERS AND STORMS MOVING INTO THE I-64 CORRIDOR. THE CHANCES WILL SPREAD SOUTH THROUGH THE REMAINDER OF THE AFTERNOON/EVENING. STILL HESITANT TO GO UP TO LIKELY POPS GIVEN THE MAIN FORCING IS EXPECTED TO STAY TO OUR NORTHEAST...BUT GIVEN THE BOUNDARY...WE SHOULD AT LEAST SEE SOME SCATTERED COVERAGE OF SHOWERS/STORMS...ESPECIALLY GIVEN THE INSTABILITY DEVELOPING AHEAD OF THE FRONT THIS AFTERNOON. BETTER SHEAR IS OFF TO OUR NORTHEAST WHERE THERE IS AN ENHANCED AREA FOR SEVERE THUNDERSTORMS. HOWEVER...WITH MARGINAL SHEAR OVER THE AREA...A FEW STORMS COULD PRODUCE A SEVERE WIND GUST. HAIL THREAT IS PRETTY LOW WITH FREEZING LEVELS AT OR ABOVE 15KFT. OVERALL...SEVERE THREAT IS NOT LOOKING ALL THAT GREAT...BUT JUST GOOD ENOUGH FOR THE SEVERE STORM PREDICTION CENTER TO MAINTAIN THE SLIGHT CHANCE OF SEVERE STORMS OVER EASTERN KENTUCKY. WILL CONTINUE TO HIGHLIGHT DAMAGING WINDS AS THE MAIN THREAT. FRONTAL BOUNDARY LOOKS TO DIVE A BIT FARTHER SOUTH TONIGHT...WHICH WILL TAKE THE CONVECTION TO THE SOUTH. ANY POSSIBLE MCS DEVELOPING UPSTREAM WILL ALSO STAY SOUTH GIVEN THE FRONTAL PLACEMENT. THIS SHOULD SPELL A DRY NIGHT. HOWEVER...WITH COOLER AIR FILTERING IN FROM THE NORTH AND SURFACE MOISTURE LIKELY LAGGING BEHIND THE FRONT...WE MAY SEE SOME DENSE FOG DEVELOP TONIGHT. GUIDANCE IS HITTING THE FOG FAIRLY HARD...AND SEE NO REASON TO NOT DO THE SAME. THUS...WILL MENTION WIDESPREAD DENSE FOG IN THE VALLEYS WITH MORE PATCHY ON THE RIDGES. THE BLUEGRASS REGION MAY MAINTAIN ENOUGH WIND TO LIMIT THE FOG POTENTIAL OUT THAT WAY. WEDNESDAY IS LOOKING MORE LIKE A DRY DAY AS THE FRONT SETTLES WELL TO OUR SOUTH. WE COULD POP OFF A SHOWER OR STORM IN SOUTHEAST KENTUCKY...BUT GUIDANCE HAS REALLY CUT BACK ON POPS FOR MOST OF THE AREA. THUS...WILL GO TOWARDS A DRIER SOLUTION FOR THE DAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH MONDAY) ISSUED AT 340 AM EDT TUE JUN 23 2015 A CHANGE TO THE OVERALL PATTERN IS ON THE HORIZON IN THE LONG TERM PERIOD. THE PERIOD WILL BEGIN WITH UPPER LEVEL HIGH STILL GENERALLY CENTERED ACROSS THE SE US WITH BEST JET ENERGY ACROSS THE GREAT LAKES AND SOUTHERN NEW ENGLAND. MODELS ARE IN GOOD AGREEMENT WITH THE RIDGE BREAKING DOWN AS WE MOVE TOWARD FRIDAY TIME FRAME WITH UPPER LEVEL HIGH SHIFTING ACROSS THE WESTERN US. THIS WILL INTRODUCE HEIGHT FALLS ACROSS THE EASTERN US AS TROUGH IS EXPECTED TO CONTINUE TO AMPLIFY/CUTOFF ACROSS THE EASTERN GREAT LAKES. HOWEVER RIGHT NOW THE GFS/CANADIAN/GFS ENSEMBLE ARE MOST AMPLIFIED COMPARED TO THE ECMWF WITH SUB 576 HEIGHTS MAKING IT INTO THE OHIO VALLEY. WEAK SURFACE HIGH WILL BE OFF TO THE NORTH AND WARM FRONT SOUTH OF THE REGION ON WEDNESDAY NIGHT TO BEGIN THE LONG TERM PERIOD. THIS WILL BE SHORT LIVED WITH ACTIVE PATTERN AND TROUGHING SETTING UP ACROSS THE EASTERN US. THE FRONT WILL MEANDER AROUND THE REGION THROUGH THE PERIOD WITH SEVERAL AREAS OF LOW PRESSURE DEVELOPING. THIS BOUNDARY WILL BE THE FOCUS OF CONVECTION THROUGH THE PERIOD AND WILL GIVE WAY TO MULTIPLE ROUNDS OF SHOWERS AND THUNDERSTORMS THURSDAY INTO SATURDAY. A FRONTAL BOUNDARY NEAR THE REGION...UPPER 60S TO LOW 70 DEWPOINTS...CAPES AOA 2000 J/KG...DCAPES NEARING 1000 J/KG...AND BULK SHEAR NEARING 30 KNOTS WITH LOWERING HEIGHTS WILL LEAD TO STRONG TO EVEN POTENTIAL FOR SEVERE STORMS THURSDAY INTO FRIDAY. THE MAIN THREAT LOOKS TO BE STRONG WINDS AND HEAVY RAIN WITH ONLY MARGINAL HAIL POTENTIAL GIVEN HIGHER FREEZING LEVELS AROUND 13 TO 14 KFT. RAIN THREAT WILL SUBSIDE AS WE MOVE LATE INTO THE WEEKEND...AS LOW PRESSURE SYSTEM AND BOUNDARY MOVE SOUTH AND EAST OF THE REGION WITH HIGH PRESSURE MOVING EAST. THIS WILL USHER IN COOLER AND DRYER CONDITIONS AS WE MOVE INTO THE SUNDAY TIME FRAME. HOWEVER UNDER NW FLOW ALOFT AND UPPER LEVEL TROUGH PASSING OVER COULD LEAD TO STRATUS DECK HANGING ON. THIS STRATUS IS SUGGESTED BY THE GFS FORECAST SOUNDINGS AND ECMWF TIME HEIGHTS. RIGHT NOW CONFIDENCE FOR MONDAY IS LOWER BUT DID OPT TO KEEP SOME SLIGHT POPS AT THIS POINT. TEMPERATURES WILL BEGIN ABOVE NORMAL FOR THIS TIME OF YEAR ON THURSDAY. TEMPERATURE FRIDAY BEGIN TO SHIFT TO AT OR NEAR NORMAL BEFORE A BELOW NORMAL SHIFT WITH HIGHS ON POTENTIALLY STAYING IN THE LOW TO MID 70S SUNDAY. THIS WOULD BE 10 OR MORE DEGREES BELOW NORMAL FOR THIS TIME OF YEAR. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 152 PM EDT TUE JUN 23 2015 A COLD FRONT IS CURRENTLY APPROACHING THE REGION...BUT IS BECOMING SHEARED OUT AS IT NEARS KENTUCKY. SOME ISOLATED LIGHT SHOWERS ARE STARTING TO SHOW UP ON THE LATEST RADAR SCANS...BUT EXPECT MOST ACTIVITY TO START UP AROUND 20Z AS WE REACH OUR CONVECTIVE TEMPERATURE. CIGS ARE MAINLY SCT ACROSS THE REGION...HIGH MVFR AND LOW END VFR. AS SHOWERS AND THUNDERSTORMS DEVELOP...EXPECT CIG HEIGHTS TO REMAIN THE SAME...THOUGH BECOMING BKN AT TIMES. ONCE THE FRONT PASSES THROUGH THE REGION THIS EVENING...EXPECT PRECIP TO COME TO AN END AND VIS AND CIGS TO GO BACK TO VFR. HOWEVER...GIVEN THE HIGH AMOUNT OF MOISTURE IN THE AREA...AND AN AREA OF HIGH PRESSURE MOVING IN BEHIND THE FRONT...STILL EXPECTING SOME GOOD POTENTIAL OF WIDESPREAD FOG DEVELOPMENT OVERNIGHT...LOCALLY DENSE AT TIMES. KEPT WITH PREVIOUS FORECAST FOR FOG LATE TONIGHT AND INTO TOMORROW MORNING. HIGH PRESSURE WILL BE THE MAIN CONTRIBUTER TOMORROW AFTER THE FOG BURNS OFF...WITH VFR CONDITIONS EXPECTED THROUGH THE REMAINDER OF THE TAF PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...JMW SHORT TERM...KAS LONG TERM...DJ AVIATION...JMW
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
123 PM EDT Tue Jun 23 2015 ...Forecast Update... Updated at 121 PM EDT Tue Jun 23 2015 Made a few updates to the forecast, mainly to delay any onset of pops and to slightly lower coverage. The latest hi-res model runs including the last few runs of the HRRR and the WRF-ARW/WRF-NMM all depict rather sparse coverage of convection this afternoon. The latest AMDAR soundings continue to depict a cap around 700-800mb. While not unbreakable, this cap coupled with very weak convergence along the effective boundary now crossing the Ohio River suggest coverage should only be about 20-30% at best, with the best chances being across southern and eastern KY. Updated at 915 AM EDT Tue Jun 23 2015 Made a few adjustments to the going forecast this morning. The latest satellite and observational trends depict a few boundaries in play today across the region. The first is the synoptic cold front, which currently lies across portions of central Ohio into central Indiana. However, another boundary was present in between Bloomington and Madison, IN. These boundaries will likely serve as the triggers for convection today, with convection already ongoing along the synoptic boundary in OH. The 00Z hi-res NCAR/NSSL ensembles along with the latest runs of the HRRR depict the similar idea of this secondary boundary currently north of Madison, IN serving as the primary focus for convection this afternoon. This would place the best chance for convective development and the resultant severe threat mainly south of the Ohio River. MLCAPEs will rise to strongly unstable levels (3000+ J/kg), but deep-layer shear (0-6km) will be lacking at only about 20 knots. Therefore, think this will be very similar to Sunday`s setup across southern KY with pulse strong/severe convection capable of marginally severe hail and isolated bouts of damaging winds given the drier mid-level air aiding in wet microburst potential. .SHORT TERM (Now through Wednesday)... Updated at 310 AM EDT Tue Jun 23 2015 ...Strong to Severe Storms Possible This Afternoon... Another round of strong to severe storms is expected today as a cold front approaches and moves through the region. This morning will start out quite warm. Temperatures across the region are still in the mid 70s to around 80. Lows are expected to be only in the mid to upper 70s. Some of the mesoscale models are suggesting a few showers will be possible across east central KY before daybreak and a boundary is approaching this region this morning, so have added isolated chances for thunderstorms there. In addition, some showers along the outflow boundary from convection over IL could move into southern IN by around daybreak. After the sun comes up we will heat up quickly with the region becoming quite unstable by mid day. Sounding from both the GFS and NAM show CAPE values of 3000+ J/kg by mid day. However, effective shear will be marginal at best, with the better shear further to the north. Storms look to develop by the 15-18Z time frame, with better coverage expected through the afternoon to early evening hours. The activity is expected to start across the northern portion of the forecast area and move south through the afternoon as the front pushes in from the north. There will be several focusing mechanisms for storms this afternoon including differential heating along the edge of the cloud shield from overnight convection, the remnant outflow boundary, and finally the front itself late in the afternoon to early evening. Strong to severe storms are possible with damaging winds and hail. The storms from this afternoon should move out from mid to late evening. Much of the overnight hours should then be quiet. However, an MCS is expected to develop across the Midwest and dive southeast overnight. The remnants of this system may affect portions of southern IN and south central KY by early Wednesday morning. However, models are variable as to the placement of this system, so will keep just low pops in the forecast late tonight into Wednesday morning for this system. Wednesday afternoon looks to be dry as high pressure builds in from the north. Temperatures today will be hot once again with highs in the upper 80s to lower 90s. Heat index values will peak in the mid 90s to around 100. With the front moving through, lows tonight will be a bit cooler than they have been lately in the mid 60s to lower 70s. Highs on Wednesday look to be just a bit cooler as well, topping out in the mid to upper 80s. .LONG TERM (Wednesday Night through Monday)... Issued at 315 AM EDT Tue Jun 23 2015 Thursday looks to be the last hot, muggy day before a pattern change brings plentiful showers/storms for Thurs night through Saturday and cooler weather for the weekend and beginning of next week. Upper level ridging centered to our south should keep much of the area dry Wed night into Thurs with the main convective activity focused to our north along a cold front. Still can`t rule out a 20-30% chance of a shower/storm Wed night/Thurs especially over southern IN closer to the boundary and ongoing convection, so will continue low precip chances. With a strong southwesterly flow on Thurs, expect temps to climb into the low to mid 90s for highs. Heat index readings should soar into the low 100s Thurs afternoon. Sensitive groups should use caution if outdoors. Thursday night the cold front will begin to push south toward our region bringing showers/storms with it. The hot, humid airmass ahead of the front will provide good fuel for convection as it enters our region. Also, models indicate that multiple ripples of weak low pressure will likely ride along the front as it pushes south into our region. Forcing and instability seem ideal for strong to severe storms as the front slowly pushes through the region Thurs night through early Saturday. An upper trough will arrive Sat morning helping to enhance forcing along the boundary. So Thursday night through Sat morning looks to be a stormy period with multiple rounds of convection possible. It`s tough to pinpoint exact timing on any strong/severe storms at this point as storm strength and evolution will be dependent on the cold front, cloud cover, and mesoscale boundaries. However, strong/severe storms will certainly be possible sometime Thur night through early Saturday with strong winds and hail being the main threats. With the cold front looking to stall over the region a bit, heavy rainfall and perhaps some minor flooding may also become a threat. Stay tuned as we go through the week and the forecast details hopefully become a bit more clear. Most of the precipitation will be clear of the area by Sat evening with Sunday being mostly dry. Another upper level shortwave and cold front will arrive for Monday bringing another chance for showers and storms. The biggest change in the weather for this weekend will be cooler temperatures behind the cold front. Highs should be limited to the upper 70s/lower 80s from Saturday through through first part of next week! Night time lows will drop back into the upper 50s/lower 60s. && .AVIATION (18Z TAF Update)... Updated at 112 PM EDT Tue Jun 23 2015 Generally VFR conditions are expected through the TAF period. Thunderstorm coverage is looking to be rather sparse this afternoon/evening as a mid-level cap keeps things at bay, therefore have removed all VCTS wording at KLEX and KSDF. Probably could also have removed it at KBWG, but guidance is still suggesting some isolated to widely scattered development possible there so will leave it in for now. Otherwise, the front moves through all sites tonight, allowing drier air to filter into the region. KBWG will be on the edge of the dry air push, so some fog will be possible there. The density of this fog will likely be dependent on the coverage of high clouds streaming in overnight from the west and just how far south the surface dry air gets. For now, will continue with just MVFR vsbys. Wednesday will be a pleasant day, with generally light winds and VFR conditions as high pressure briefly builds into the Ohio Valley. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...NONE. IN...NONE. && $$ Update.........KJD Short Term.....EER Long Term......AMS Aviation.......KJD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
344 PM EDT TUE JUN 23 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT TUE JUN 23 2015 WV IMAGERY AND RAP ANALYSIS CONTINUES TO INDICATE A ZONAL FLOW PATTERN ACROSS THE NRN CONUS. MAIN SHORTWAVE WHICH SUPPORTED THUNDERSTORMS ACROSS THE UPPER GREAT LAKES LAST EVENING HAS NOW LIFTED NE OF LAKE SUPERIOR. RESIDUAL LIGHT SHRA/DZ OVER CENTRAL UPPER MI EARLIER THIS MORNING FROM THIS FEATURE HAS NOW ENDED ...ALTHOUGH SOME STRATUS PRESENTLY STILL LINGERS OVER THE AREA. ALSO WNW WINDS REMAIN QUITE BREEZY (NEAR 30 MPH) OVER THE ERN HALF OF THE CWA AS COLD ADVECTION BEHIND THE SYSTEM ALLOWS FOR SOME MIXING OF STRONGER WINDS JUST OFF THE SFC. UPSTREAM SHORTWAVE OVER SRN MANITOBA IS PROGGED TO BRING IN SHRA TO THE AREA TONIGHT. TODAY...DRYING AND ASSOCIATED SUBSIDENCE FROM HIGH PRES BUILDING IN FROM THE UPPER MS VALLEY WILL CLEAR OUT LINGERING STRATUS THIS MORNING...YIELDING MOSTLY SUNNY SKIES WHILE WNW WINDS DIMINISH. TEMPS WILL BE NEAR SEASONAL AVERAGES...GENERALLY FROM THE LOWER TO MID 70S. TONIGHT...THE SHORTWAVE FROM SRN MANITOBA WILL MOVE ACROSS NRN LAKE SUPERIOR THIS EVENING AS FORCING ASSOC WITH THIS FEATURE GENERALLY STAYS NORTH OF UPPER MI. HAVE INTRODUCED SOME LOW CHC POPS FOR SHRA OVER LAKE SUPERIOR TONIGHT WITH SOME SLIGHT CHC POPS OVER NW UPPER MI AS A WEAK SFC TROUGH MOVES ACROSS THE REGION ALTHOUGH AVAILABLE MOISTURE WITH THIS SYSTEM WL BE LIMITED. EXPECT LOWS IN THE 50S. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 344 PM EDT TUE JUN 23 2015 SEVERAL PERIODS OF LIGHT SHOWERS ARE EXPECTED ACROSS UPPER MICHIGAN DURING THE LONG TERM PERIOD...FIRST ON WEDNESDAY NIGHT INTO THURSDAY...AND AGAIN DURING THE LATER PART OF THE WEEKEND AND INTO EARLY NEXT WEEK. THERE ARE A COUPLE SHORTWAVES THAT WILL AFFECT THE AREA DURING THE WEDNESDAY NIGHT INTO THURSDAY TIME FRAME...WITH THE STRONGER CONVECTION LIKELY WITH THE ACROSS IOWA...SOUTHERN WISCONSIN...AND NORTHERN ILLINOIS WITH THE WARM FRONT AND RUNNING ALONG THE TIGHT INSTABILITY GRADIENT. FARTHER TO THE NORTH...A STRONGER SHORTWAVE WILL BE MOVING EAST-SOUTHEAST OUT OF NORTHERN MINNESOTA LATE WEDNESDAY AFTERNOON AND ACROSS UPPER MICHIGAN WEDNESDAY NIGHT INTO THURSDAY. THINK THE BETTER OPPORTUNITY FOR SHOWERS WILL COME DURING THE EVENING HOURS WITH THE RESIDUAL DIURNAL HEATING SHOWERS AND THEN AGAIN HELPED BY DIURNAL HEATING ON THURSDAY. WITH THE WAVE AROUND DURING THE OVERNIGHT HOURS ON WEDNESDAY...WILL KEEP CHANCE POPS IN PLACE OVER THE AREA. DID TRY TO PROVIDE A LITTLE DEFINITION ON THE POPS OVER THE NORTHERN U.P. ON THURSDAY...AS THE LIGHT NORTHERLY FLOW OFF THE LAKE SHOULD LIMIT THE SHOWER POTENTIAL NEAR LAKE SUPERIOR. AN AREA OF HIGH PRESSURE WILL DROP SOUTHEAST ACROSS THE UPPER GREAT LAKES REGION FRIDAY INTO SATURDAY AND WILL KEEP THE AREA MAINLY DRY. THERE ARE SOME HINTS OF A FEW DIURNAL SHOWERS DEVELOPING ON FRIDAY ALONG THE LAKE BREEZES...OTHERWISE SHOULD SEE PARTLY CLOUDY TO MOSTLY CLEAR SKIES OVER THE AREA. THE WAVES FROM MID-LATE THIS WEEK WILL HELP AMPLIFY AN UPPER TROUGH OVER THE EASTERN HALF OF THE CONUS FOR THIS WEEKEND. WHILE THE TROUGH WILL WEAKEN AND SHIFT EAST INTO EARLY NEXT WEEK...A SERIES OF SHORTWAVES DROPPING SOUTHEAST INTO THE GREAT LAKES REGION SUNDAY INTO TUESDAY WILL REINFORCE THE UPPER TROUGH OVER THE GREAT LAKES REGION FOR NEXT WEEK. THAT WILL LEAD TO NORMAL TO BELOW NORMAL TEMPERATURES AND OPPORTUNITIES FOR RAIN SHOWERS AND MAYBE A FEW THUNDERSTORMS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 150 PM EDT TUE JUN 23 2015 VFR CEILINGS AND VIS ARE EXPECTED TO CONTINUE OVER THE NEXT 24 HOURS. A DISTURBANCE/COLD FRONT SLIDING IN FROM THE NORTHWEST TONIGHT WILL BRING THE POTENTIAL FOR A FEW SHOWERS AT CMX THIS EVENING...AND A BETTER CHANCE AT SAW WEDNESDAY LATE MORNING/EARLY AFTERNOON WITH THE ASSISTANCE OF DAYTIME HEATING AS THE COLD FRONT SINKS S ACROSS UPPER MI. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT TUE JUN 23 2015 A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF A LOW LIFTING INTO QUEBEC TODAY WILL CONTINUE TO SUPPORT WNW 35 KNOT GALES EARLY THIS MORNING OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN ALLOW WINDS TO DIE DOWN BY MIDDAY AND KEEP WINDS LIGHT FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS MAY ALLOW PATCHY FOG TO LINGER OVER ERN LAKE SUPERIOR EARLY THIS MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...KF MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
151 PM EDT TUE JUN 23 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 523 AM EDT TUE JUN 23 2015 WV IMAGERY AND RAP ANALYSIS CONTINUES TO INDICATE A ZONAL FLOW PATTERN ACROSS THE NRN CONUS. MAIN SHORTWAVE WHICH SUPPORTED THUNDERSTORMS ACROSS THE UPPER GREAT LAKES LAST EVENING HAS NOW LIFTED NE OF LAKE SUPERIOR. RESIDUAL LIGHT SHRA/DZ OVER CENTRAL UPPER MI EARLIER THIS MORNING FROM THIS FEATURE HAS NOW ENDED ...ALTHOUGH SOME STRATUS PRESENTLY STILL LINGERS OVER THE AREA. ALSO WNW WINDS REMAIN QUITE BREEZY (NEAR 30 MPH) OVER THE ERN HALF OF THE CWA AS COLD ADVECTION BEHIND THE SYSTEM ALLOWS FOR SOME MIXING OF STRONGER WINDS JUST OFF THE SFC. UPSTREAM SHORTWAVE OVER SRN MANITOBA IS PROGGED TO BRING IN SHRA TO THE AREA TONIGHT. TODAY...DRYING AND ASSOCIATED SUBSIDENCE FROM HIGH PRES BUILDING IN FROM THE UPPER MS VALLEY WILL CLEAR OUT LINGERING STRATUS THIS MORNING...YIELDING MOSTLY SUNNY SKIES WHILE WNW WINDS DIMINISH. TEMPS WILL BE NEAR SEASONAL AVERAGES...GENERALLY FROM THE LOWER TO MID 70S. TONIGHT...THE SHORTWAVE FROM SRN MANITOBA WILL MOVE ACROSS NRN LAKE SUPERIOR THIS EVENING AS FORCING ASSOC WITH THIS FEATURE GENERALLY STAYS NORTH OF UPPER MI. HAVE INTRODUCED SOME LOW CHC POPS FOR SHRA OVER LAKE SUPERIOR TONIGHT WITH SOME SLIGHT CHC POPS OVER NW UPPER MI AS A WEAK SFC TROUGH MOVES ACROSS THE REGION ALTHOUGH AVAILABLE MOISTURE WITH THIS SYSTEM WL BE LIMITED. EXPECT LOWS IN THE 50S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 328 AM EDT TUE JUN 23 2015 BEST CHANCES FOR PRECIP WILL BE INLAND FROM LAKE SUPERIOR WEDNESDAY THROUGH THU AS SHORTWAVE ENERGY MOVES THROUGH. BEST CHANCES WILL BE DURING THE DAY WED WITH DIURNAL HEATING AND WED NIGHT AS THE MAIN SHORTWAVE ENERGY MOVES THROUGH...ALTHOUGH THERE IS DISAGREEMENT BETWEEN MODELS. CAPE LOOKS FAIRLY LIMITED AT OR BELOW 500J/KG...SO WILL KEEP ONLY SLIGHT THUNDER CHANCES...BUT AMPLE MOISTURE AND SLOW STORM MOVEMENT DUE TO WEAK LOW LEVEL WINDS WILL ALLOW FOR THREAT OF SOME PROLONGED HEAVY RAIN ON WED. HOWEVER...RAINFALL AMOUNTS ARE STILL UNCERTAIN. ADDITIONAL SHORTWAVE ENERGY LOOKS TO MOVE THROUGH THU...BUT LATEST MODEL RUNS KEEP THAT FARTHER SW...SO THE BEST POPS ARE FOR AREAS ALONG THE WI BORDER. A SFC HIGH MOVES THROUGH THU NIGHT INTO SAT NIGHT...BRINGING MOSTLY DRY WEATHER AND DECREASED CLOUDINESS. MODELS SHOW A SHORTWAVE MOVING THROUGH THE AREA SUN INTO MON...WITH DISAGREEMENT ON TIMING...WHICH WILL BRING RAIN TO THE AREA AS IT PASSES. THE SHORTWAVES LOOK TO AMPLIFY AN UPPER TROUGH OVER THE GREAT LAKES...WHICH MAY STICK AROUND INTO EARLY JULY. TEMPERATURES THROUGH THE NEXT 7 DAYS LOOK TO BE NEAR OR JUST BELOW NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 150 PM EDT TUE JUN 23 2015 VFR CEILINGS AND VIS ARE EXPECTED TO CONTINUE OVER THE NEXT 24 HOURS. A DISTURBANCE/COLD FRONT SLIDING IN FROM THE NORTHWEST TONIGHT WILL BRING THE POTENTIAL FOR A FEW SHOWERS AT CMX THIS EVENING...AND A BETTER CHANCE AT SAW WEDNESDAY LATE MORNING/EARLY AFTERNOON WITH THE ASSISTANCE OF DAYTIME HEATING AS THE COLD FRONT SINKS S ACROSS UPPER MI. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 523 AM EDT TUE JUN 23 2015 A TIGHT PRES GRADIENT AND COLD ADVECTION ON THE BACK SIDE OF A LOW LIFTING INTO QUEBEC TODAY WILL CONTINUE TO SUPPORT WNW 35 KNOT GALES EARLY THIS MORNING OVER THE EAST HALF OF LAKE SUPERIOR. HIGH PRES BUILDING BACK OVER THE AREA WILL THEN ALLOW WINDS TO DIE DOWN BY MIDDAY AND KEEP WINDS LIGHT FROM LATE TUE INTO FRI. LINGERING LOW-LVL MOISTURE AND HIGH DEWPOINTS MAY ALLOW PATCHY FOG TO LINGER OVER ERN LAKE SUPERIOR EARLY THIS MORNING. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...KF MARINE...VOSS
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
222 PM CDT Tue Jun 23 2015 ...Hot and Steamy Weather Continues Through Mid Week...Cold Front Will Bring Rain and Cooler Weather End of the Week... .SHORT TERM...(This Evening through Thursday) Issued at 200 PM CDT TUE JUN 23 2015 A front has stalled out across the area. This frontal boundary shows up very nicely on the visible satellite imagery and surface obs this afternoon. The front was currently located from near Nevada to near Eminence. This front will start to slowly back up northward later this evening and tonight. There is a complex of storms northwest of the Kansas City area which are moving east- southeastward. The latest Hi-Res models suggest this complex if it holds together may clip our central Missouri counties late this afternoon and early evening. The HRRR and the ARW continues to suggest a few isolated showers and storms developing near the stalled out frontal boundary across central Missouri into the eastern Missouri Ozarks. There will be a limited risk for a strong storm or two with small hail and gusty winds as the main threat. Any convection should either dissipate or move off to the east of the area after sunset. Wednesday and Thursday will be hot and humid with the upper level ridge nosing in a bit over the area. High temperatures may be a couple degrees warmer than today with most areas in the lower to middle 90s. Heat index will be around 100. Southwest winds will be gusty up to 30 mph for areas west of Highway 65. .LONG TERM...(Thursday Night through Tuesday) Issued at 200 PM CDT TUE JUN 23 2015 A stronger shortwave will move through the Midwest and Ohio River Valley region on Friday. This feature will begin to carve out a trough across the eastern U.S. while an upper level ridge builds across the western U.S. A cold front will move down into the region starting Thursday night. Showers and thunderstorms will begin to impact portions of central Missouri late Thursday night and area wide by Friday. Will not rule out a few strong storms possible Friday with gusty winds and small hail the main threats. The front will clear through the area by Friday night with rain ending from north to south. The weekend is shaping up to be extremely nice. Drier air will move into the area with dewpoints in the 50s. The latest model guidance came in a degree or two cooler with lows Saturday night and Sunday night in the upper 50s to lower 60s. Highs will be in the upper 70s to lower 80s and Mostly sunny skies. Looks like the below average temperatures will continue into early next week. Another weak front may try to move into the area by Monday night with a few showers and storms possible. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon) Issued at 1220 PM CDT TUE JUN 23 2015 Conditions will remain VFR at the terminals through the period. A front located north of SGF could trigger some thunderstorms this afternoon however these would likely remain north and east of SGF. West winds will prevail this afternoon and evening before turning back towards the south overnight. Low level wind shear looks even less likely than previous nights. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$ SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Burchfield
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
659 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...THEN BECOME STATIONARY AND LINGER IN THE AREA THROUGH THE WEEKEND. IT WILL FINALLY MOVE OFF THE COAST EARLY NEXT WEEK. && .NEAR TERM /TONIGHT/... AS OF 7 PM TUE...MAIN CHANGE WAS TO DECREASE POPS THIS EVENING. CONVECTIVE CHANCES HAVE DIMINISHED THIS EVENING AS FOCUS HAS BEEN FURTHER NORTH AND WEST. NEAR TERM GUIDANCE AND VARIOUS CAMS INDICATE ANY CONVECTION FROM WV/VA WILL NOT ENTER E NC UNTIL WELL AFTER MIDNIGHT...IF IT IS ABLE TO HOLD TOGETHER AS THE STORMS WILL MOVE INTO A MORE STABILIZING ENVIRONMENT WITH LOSS OF HEATING. HAVE CHANCE POPS RELEGATED TO THE NORTHERN AND NORTHEASTERN TIER OF THE FA. LOWS VERY WARM AND MUGGY...MID/UPR 70S INLAND TO 80-82 COAST. ONLY OTHER CHANGE WAS TO EXPIRE THE HEAT ADVISORY. PREVIOUS DISCUSSION...AS OF 3 PM TUE...SFC ANALYSIS SHOWS BERMUDA HIGH EXTENDING OVER THE AREA FROM OFFSHORE AND TROUGHING INLAND. HEAT ADVISORY CONTINUES ALL COUNTIES EXCEPT OUTER BANKS HYDE THROUGH EARLY THIS EVENING...WITH HEAT INDEX VALUES 105-110 THIS AFTERNOON. ISOLATED TO SCATTERED SEABREEZE SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON...PER NSSL WRF AND HRRR. EXPECT MOST CONVECTION TO WANE WITH LOSS OF HEATING EARLY THIS EVENING. THEN COULD SEE ADDITIONAL CONVECTION MOVE INTO THE NORTHERN TIER FROM THE NW AHEAD OF THE APPROACHING FRONTAL BOUNDARY. NSSL WRF AND HRRR SHOW A LINE MOVING IN BTWN 03-08Z TONIGHT...THOUGH WEAKENING AS IT MOVES SE INTO NE NC. AN ISOLATED STRONG TSTM WITH GUSTY WINDS WILL BE POSSIBLE THIS AFTERNOON AND TONIGHT. LOWS OVERNIGHT SIMILAR TO PAST SEVERAL NIGHTS 75-80 DEGREES. && .SHORT TERM /WEDNESDAY/... AS OF 3 PM TUE...FRONT WILL CONTINUE TO SAG SOUTH INTO THE REGION WEDNESDAY...STALLING OVER THE CWA. EXPECT THE BOUNDARY TO STALL OVER THE SOUTHERN COAST WED AFTERNOON...WITH STILL SOME UNCERTAINTY ON HOW FAR SOUTH IT MAKES IT. THE FRONT IN CONJUNCTION WITH THE SEABREEZE...LIKELY BEING PINNED ALONG THE COAST WITH THE NORTHERLY FLOW TO THE NORTH...WILL LIKELY BE A FOCUS OF ENHANCED CONVERGENCE AND TSTM DEVELOPMENT DURING THE AFTERNOON/EVENING. INCREASED POPS TO HIGHER CHANCE FOR WED AFTERNOON...WITH BEST CHANCES EXPECTED ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. GIVEN THE UNSTABLE AIRMASS AND MARGINAL SHEAR...ISOLATED STRONG TSTMS WITH GUSTY WINDS WILL BE POSSIBLE. LOCALLY HEAVY RAIN AN ADDITIONAL THREAT WITH PWAT VALUES AT OR ABOVE 2 INCHES. TEMPS A FEW DEGREES COOLER AS UPPER RIDGE BEGINS TO WEAKEN COUPLED WITH CLOUD COVER...AND NORTHERN FORECAST AREA UNDER MORE OF A NLY SFC FLOW. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 17-19C SUPPORT HIGHS IN THE UPPER 80S TO MID 90S. WARMEST IN THE S/SW COUNTIES. COULD SEE BRIEF HEAT ADVISORY CRITERIA FOR THOSE AREAS WED AFTERNOON...BUT WILL LET NEXT SHIFT RE-EVALUATE THE NEED FOR AN ADVISORY. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... AS OF 315 PM TUESDAY...A GRADUAL PATTERN CHANGE IS EXPECTED MID/LATE WEEK AS THE HOT AND HUMID WEATHER IS REPLACED BY A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. WEDNESDAY NIGHT...A WEAK BACK DOOR COLD FRONT WILL BISECT SOUTHERN PORTIONS OF THE MHX CWA WED NIGHT AND WILL PUSH FAR ENOUGH OFFSHORE TO ALLOW WINDS TO SHIFT SOUTHEASTERLY BY SUNRISE THURSDAY MORNING. HELD ON TO LOW SLIGHT CHANCE POPS WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING. LOWS WILL RANGE LOW 70S INLAND TO MID 70S ALONG THE COAST. THURSDAY THROUGH FRIDAY...ZONAL FLOW ALOFT WILL PREVAIL THURSDAY THROUGH FRIDAY WITH UPPER HEIGHTS FALLING SLIGHTLY. ANOTHER BACKDOOR COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE FRIDAY AND WILL BE THE FOCUS FOR SHOWERS/THUNDERSTORMS FRI AFTERNOON FOR AREAS ALONG AND NORTH OF HWY 64. EXPECT A CHANCE OF THUNDERSTORMS AGAIN THURSDAY AFTERNOON INTO THURSDAY NIGHT. WITH MORE CLOUD COVER EXPECTED THURSDAY, TEMPERATURES WILL BE A DEGREE OR TWO COOLER, BUT WITH HIGH DEWPOINTS LINGERING WILL STILL LIKELY SEE SOME HEAT INDEX VALUES AROUND 100 DEGREES. LOWS THURSDAY NIGHT WILL REMAIN MILD, LOW/MID 70S. FRIDAY NIGHT THROUGH SUNDAY...THE COMBINATION OF A STALLED FRONTAL BOUNDARY NEAR OR ACROSS THE CWA AND AN UPPER TROUGH DIGGING INTO THE EASTERN CONUS WILL LEAD TO A WETTER PATTERN FOR THE WEEKEND. MID-LEVEL TROUGH WILL DIG SOUTHEAST WITH TIME THROUGH THE WEEKEND TAPPING A GOOD FEED OF GULF MOISTURE. AN AREA OF LOW PRESSURE WILL DEVELOP OFF/ALONG THE MID-ATLANTIC COAST SUNDAY AS THE UPPER TROUGH AXIS SHIFTS EAST. WILL CONTINUE PREVIOUS FORECAST TREND OF HIGH CHANCE POPS SATURDAY INTO SUNDAY. GUIDANCE SHOWING PWATS IN THE 2-2.25 INCH RANGE SATURDAY INTO SUNDAY, APPROACHING 2 STANDARD DEVIATIONS ABOVE NORMAL FOR JUNE. HIGH TEMPS WILL FALL INTO THE UPPER 80S OVER THE WEEKEND IN MANY SPOTS DUE TO MORE CLOUD COVER AND RAIN WITH LOWS IN THE LOW/MID 70S. MONDAY INTO TUESDAY...THE SURFACE LOW WILL MOVE INTO THE NORTHWESTERN ATLANTIC OCEAN OFF NEW ENGLAND MONDAY AS A SHORTWAVE TROUGH EMBEDDED IN THE LARGER SCALE UPPER TROUGH SHIFTS NORTHEAST INTO THE CANADIAN MARITIMES. HIGH PRESSURE WILL BUILD IN FROM THE WEST MONDAY AND CONTINUE THROUGH TUESDAY WITH TEMPS EXPECTED TO BE NEAR CLIMATOLOGY, UPPER 80S FOR HIGHS AND LOWS IN THE UPPER 60S TO LOWER 70S. && .AVIATION /00Z WEDNESDAY THROUGH SUNDAY/... SHORT TERM /THROUGH WEDNESDAY/... AS OF 7 PM TUESDAY...VFR WILL PREVAIL AS HIGH PRES REMAINS IN CONTROL. OVERNIGHT...AN APPROACHING COLD FRONT FROM THE NORTHWEST COULD BRING VCTS/VCSH...BUT CONFIDENCE IS LOW TO ADD IN THE TAFS AS HI- RES MODELS ARE SHOWING THE CONVECTION WEAKENING AS IT APPROACHES OUR AREA. SIMILAR TO LAST NIGHT...COULD SEE BRIEF PATCHY FOG DEVELOP ACROSS AREAS AWAY FROM THE COAST. BETTER CHANCE FOR SCT THUNDERSTORMS WED AFTERNOON AS FRONT WILL BE ALONG OR SOUTH OF A KINSTON TO CAPE HATTERAS LINE. WILL NOT ADD VCTS IN TAFS AT THIS TIME DUE TO SCT NATURE OF THE STORMS...BUT BEST CHANCE OF SEEING THUNDER ARE KISO/KOAJ/KEWN. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 335 PM TUESDAY...SUB-VFR CONDITIONS POSSIBLE WEDNESDAY NIGHT THROUGH SUNDAY AS A SERIES OF WEAK SURFACE FRONTS SHIFT INTO THE REGION WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FRIDAY THROUGH SUNDAY. MAY SEE SOME AREAS OF MVFR CEILINGS AND VSBYS WITH LATE NIGHT STRATUS AND FOG IN AREAS WHERE HEAVIEST RAIN OCCURS. && .MARINE... SHORT TERM /THROUGH WEDNESDAY/... AS OF 3 PM TUE...LATEST OBS SHOW SW WINDS 10-20KT AND SEAS 2-4FT. COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TONIGHT TIGHTENING THE PRESSURE GRADIENT...WITH WINDS INCREASING TO 15-25KT ACROSS MOST OF THE WATERS AND SOUNDS. SCA CONTINUES FOR THE WATERS AND PAMLICO SOUND THROUGH TONIGHT AND INTO WED MORNING FOR GUSTY WINDS AND BUILDING SEAS 4-6FT. THE FRONT WILL CONTINUE TO SAG SOUTH AND STALL OVER THE SOUTHERN WATERS WED AFTERNOON...MAKING WIND DIRECTIONS CHALLENGING. WSW WINDS WILL START OFF WED...THEN VEERING NORTH OF LOOKOUT THROUGH THE DAY BECOMING NORTHERLY 5-15KT BEHIND THE BOUNDARY AND SW AHEAD OF IT. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 335 PM TUESDAY...A WEAK FRONTAL BOUNDARY WILL SHIFT WELL OFFSHORE WEDNESDAY NIGHT WITH WINDS BECOMING SOUTHEASTERLY LATE, 10 KNOTS OR LESS WITH SEAS GENERALLY 1-3 FT. HIGH PRESSURE OFFSHORE AND WEAK TROUGH DEVELOPING INLAND THURSDAY WILL RESULT IN SOUTHWESTERLY WINDS 10-20 KT WITH SEAS 3-5 FT THURSDAY EVENING INTO THURSDAY NIGHT, AND MAY SEE A FEW 6 FT SEAS FOR THE OUTER PORTIONS OF THE CENTRAL AND SOUTHERN WATERS. SMALL CRAFT ADVISORY CONDITIONS WILL BE POSSIBLE FRIDAY AND FRIDAY EVENING FOR THE CENTRAL AND SOUTHERN WATERS DUE TO WINDS GUSTING NEAR 25 KT AND SEAS UP TO 6 FT. A BACKDOOR COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE FRIDAY AND MOVE INTO THE EASTERN NC COASTAL WATERS SATURDAY, CREATING A COMPLEX WINDS/SEAS FORECAST HIGHLY DEPENDENT ON THE LOCATION OF THIS FRONTAL FEATURE. MAY SEE NORTHEASTERLY WINDS FOR THE ALBEMARLE SOUND AND COASTAL WATERS NORTH OF OREGON INLET SATURDAY NIGHT, THEN THE FRONT IS FORECAST TO SLOWLY SHIFT SOUTH SUNDAY AND OFF THE COAST BY SUNDAY EVENING/NIGHT WITH NORTH TO NORTHEASTERLY WINDS 10-15 KT OVERSPREADING THE EASTERN NC COASTAL WATERS SUNDAY NIGHT THROUGH MONDAY. THE FRONT SHIFTS WELL OFFSHORE MONDAY NIGHT INTO TUESDAY ALLOWING WINDS TO SHIFT EAST THEN SOUTHEASTERLY DURING THE DAY TUESDAY. SEAS WILL BUILD UP TO 6 FT FOR THE OUTER FRINGES OF THE COASTAL WATERS THIS WEEKEND THEN SLOWLY DIMINISH TO 3-5 FT LATE SUNDAY INTO MONDAY. LOCAL SWAN/NWPS AND WAVEWATCH IN GOOD AGREEMENT FOR THE MEDIUM RANGE THEN WAVEWATCH APPEARS REASONABLE FOR THE EXTENDED PERIOD. && .CLIMATE... RECORD HIGH TEMPERATURES TUESDAY: 6/23 LOCATION-----TEMP/YEAR--NOTES NEW BERN 98/1988 (KEWN ASOS) HATTERAS 88/1996 (KHSE ASOS) GREENVILLE 100/1933 (COOP - NOT KPGV ASOS) MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS) KINSTON 102/1911 (COOP - NOT KISO ASOS) JACKSONVILLE 99/2010 (KNCA AWOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT WEDNESDAY FOR AMZ135. SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY FOR AMZ152-154- 156. SMALL CRAFT ADVISORY UNTIL 5 AM EDT WEDNESDAY FOR AMZ150. SMALL CRAFT ADVISORY UNTIL 8 AM EDT WEDNESDAY FOR AMZ158. && $$ SYNOPSIS...CQD/HSA NEAR TERM...CQD/TL SHORT TERM...CQD LONG TERM...DAG AVIATION...DAG/TL/BM MARINE...CQD/DAG CLIMATE...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
343 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...THEN BECOME STATIONARY AND LINGER IN THE AREA THROUGH THE WEEKEND. IT WILL FINALLY MOVE OFF THE COAST EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 3 PM TUE...SFC ANALYSIS SHOWS BERMUDA HIGH EXTENDING OVER THE AREA FROM OFFSHORE AND TROUGHING INLAND. HEAT ADVISORY CONTINUES ALL COUNTIES EXCEPT OUTER BANKS HYDE THROUGH EARLY THIS EVENING...WITH HEAT INDEX VALUES 105-110 THIS AFTERNOON. ISOLATED TO SCATTERED SEABREEZE SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON...PER NSSL WRF AND HRRR. EXPECT MOST CONVECTION TO WANE WITH LOSS OF HEATING EARLY THIS EVENING. THEN COULD SEE ADDITIONAL CONVECTION MOVE INTO THE NORTHERN TIER FROM THE NW AHEAD OF THE APPROACHING FRONTAL BOUNDARY. NSSL WRF AND HRRR SHOW A LINE MOVING IN BTWN 03-08Z TONIGHT...THOUGH WEAKENING AS IT MOVES SE INTO NE NC. AN ISOLATED STRONG TSTM WITH GUSTY WINDS WILL BE POSSIBLE THIS AFTERNOON AND TONIGHT. LOWS OVERNIGHT SIMILAR TO PAST SEVERAL NIGHTS 75-80 DEGREES. && .SHORT TERM /WEDNESDAY/... AS OF 3 PM TUE...FRONT WILL CONTINUE TO SAG SOUTH INTO THE REGION WEDNESDAY...STALLING OVER THE CWA. EXPECT THE BOUNDARY TO STALL OVER THE SOUTHERN COAST WED AFTERNOON...WITH STILL SOME UNCERTAINTY ON HOW FAR SOUTH IT MAKES IT. THE FRONT IN CONJUNCTION WITH THE SEABREEZE...LIKELY BEING PINNED ALONG THE COAST WITH THE NORTHERLY FLOW TO THE NORTH...WILL LIKELY BE A FOCUS OF ENHANCED CONVERGENCE AND TSTM DEVELOPMENT DURING THE AFTERNOON/EVENING. INCREASED POPS TO HIGHER CHANCE FOR WED AFTERNOON...WITH BEST CHANCES EXPECTED ACROSS THE SOUTHERN HALF OF THE FORECAST AREA. GIVEN THE UNSTABLE AIRMASS AND MARGINAL SHEAR...ISOLATED STRONG TSTMS WITH GUSTY WINDS WILL BE POSSIBLE. LOCALLY HEAVY RAIN AN ADDITIONAL THREAT WITH PWAT VALUES AT OR ABOVE 2 INCHES. TEMPS A FEW DEGREES COOLER AS UPPER RIDGE BEGINS TO WEAKEN COUPLED WITH CLOUD COVER...AND NORTHERN FORECAST AREA UNDER MORE OF A NLY SFC FLOW. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 17-19C SUPPORT HIGHS IN THE UPPER 80S TO MID 90S. WARMEST IN THE S/SW COUNTIES. COULD SEE BRIEF HEAT ADVISORY CRITERIA FOR THOSE AREAS WED AFTERNOON...BUT WILL LET NEXT SHIFT RE-EVALUATE THE NEED FOR AN ADVISORY. && .LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/... AS OF 315 PM TUESDAY...A GRADUAL PATTERN CHANGE IS EXPECTED MID/LATE WEEK AS THE HOT AND HUMID WEATHER IS REPLACED BY A BETTER CHANCE OF SHOWERS AND THUNDERSTORMS. WEDNESDAY NIGHT...A WEAK BACK DOOR COLD FRONT WILL BISECT SOUTHERN PORTIONS OF THE MHX CWA WED NIGHT AND WILL PUSH FAR ENOUGH OFFSHORE TO ALLOW WINDS TO SHIFT SOUTHEASTERLY BY SUNRISE THURSDAY MORNING. HELD ON TO LOW SLIGHT CHANCE POPS WEDNESDAY NIGHT INTO EARLY THURSDAY MORNING. LOWS WILL RANGE LOW 70S INLAND TO MID 70S ALONG THE COAST. THURSDAY THROUGH FRIDAY...ZONAL FLOW ALOFT WILL PREVAIL THURSDAY THROUGH FRIDAY WITH UPPER HEIGHTS FALLING SLIGHTLY. ANOTHER BACKDOOR COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE FRIDAY AND WILL BE THE FOCUS FOR SHOWERS/THUNDERSTORMS FRI AFTERNOON FOR AREAS ALONG AND NORTH OF HWY 64. EXPECT A CHANCE OF THUNDERSTORMS AGAIN THURSDAY AFTERNOON INTO THURSDAY NIGHT. WITH MORE CLOUD COVER EXPECTED THURSDAY, TEMPERATURES WILL BE A DEGREE OR TWO COOLER, BUT WITH HIGH DEWPOINTS LINGERING WILL STILL LIKELY SEE SOME HEAT INDEX VALUES AROUND 100 DEGREES. LOWS THURSDAY NIGHT WILL REMAIN MILD, LOW/MID 70S. FRIDAY NIGHT THROUGH SUNDAY...THE COMBINATION OF A STALLED FRONTAL BOUNDARY NEAR OR ACROSS THE CWA AND AN UPPER TROUGH DIGGING INTO THE EASTERN CONUS WILL LEAD TO A WETTER PATTERN FOR THE WEEKEND. MID-LEVEL TROUGH WILL DIG SOUTHEAST WITH TIME THROUGH THE WEEKEND TAPPING A GOOD FEED OF GULF MOISTURE. AN AREA OF LOW PRESSURE WILL DEVELOP OFF/ALONG THE MID-ATLANTIC COAST SUNDAY AS THE UPPER TROUGH AXIS SHIFTS EAST. WILL CONTINUE PREVIOUS FORECAST TREND OF HIGH CHANCE POPS SATURDAY INTO SUNDAY. GUIDANCE SHOWING PWATS IN THE 2-2.25 INCH RANGE SATURDAY INTO SUNDAY, APPROACHING 2 STANDARD DEVIATIONS ABOVE NORMAL FOR JUNE. HIGH TEMPS WILL FALL INTO THE UPPER 80S OVER THE WEEKEND IN MANY SPOTS DUE TO MORE CLOUD COVER AND RAIN WITH LOWS IN THE LOW/MID 70S. MONDAY INTO TUESDAY...THE SURFACE LOW WILL MOVE INTO THE NORTHWESTERN ATLANTIC OCEAN OFF NEW ENGLAND MONDAY AS A SHORTWAVE TROUGH EMBEDDED IN THE LARGER SCALE UPPER TROUGH SHIFTS NORTHEAST INTO THE CANADIAN MARITIMES. HIGH PRESSURE WILL BUILD IN FROM THE WEST MONDAY AND CONTINUE THROUGH TUESDAY WITH TEMPS EXPECTED TO BE NEAR CLIMATOLOGY, UPPER 80S FOR HIGHS AND LOWS IN THE UPPER 60S TO LOWER 70S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... SHORT TERM /THROUGH WEDNESDAY/... AS OF 120 PM TUESDAY...HIGH CONFIDENCE OF VFR CONDITIONS WILL PREVAIL FOR MOST OF THE TAF PERIOD. SURFACE HIGH PRESSURE EXTENDING OVER EASTERN NC FROM THE WESTERN ATLANTIC OCEAN AND TROUGH INLAND. EXPECT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG THE SEABREEZE THIS AFTERNOON. MOST OF THE SHOWERS/THUNDERSTORMS SHOULD WANE WITH THE LOSS OF HEATING EARLY THIS EVENING. OVERNIGHT...AN APPROACHING COLD FRONT FROM THE NORTHWEST COULD BRING VCTS/VCSH...BUT CONFIDENCE IS LOW TO ADD IN THE TAFS AS HI- RES MODELS ARE SHOWING THE RAIN WEAKENING AS ITS APPROACHING OUR AREA. PLUS...COULD SEE PATCHY FOG DEVELOP TOWARDS EARLY MORNING (APPROX. 10Z) AND THEREFORE ADDED 5SM FOR OUR INLAND TAF SITES (PGV/ISO). WINDS WILL BECOME LIGHT AND VARIABLE TOMORROW MORNING AS THE COLD FRONT CROSSES THE AREA UNDER SCATTERED CLOUDS AT 4KFT. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 335 PM TUESDAY...SUB-VFR CONDITIONS POSSIBLE WEDNESDAY NIGHT THROUGH SUNDAY AS A SERIES OF WEAK SURFACE FRONTS SHIFT INTO THE REGION WITH INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS FRIDAY THROUGH SUNDAY. MAY SEE SOME AREAS OF MVFR CEILINGS AND VSBYS WITH LATE NIGHT STRATUS AND FOG IN AREAS WHERE HEAVIEST RAIN OCCURS. && .MARINE... SHORT TERM /THROUGH WEDNESDAY/... AS OF 3 PM TUE...LATEST OBS SHOW SW WINDS 10-20KT AND SEAS 2-4FT. COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TONIGHT TIGHTENING THE PRESSURE GRADIENT...WITH WINDS INCREASING TO 15-25KT ACROSS MOST OF THE WATERS AND SOUNDS. SCA CONTINUES FOR THE WATERS AND PAMLICO SOUND THROUGH TONIGHT AND INTO WED MORNING FOR GUSTY WINDS AND BUILDING SEAS 4-6FT. THE FRONT WILL CONTINUE TO SAG SOUTH AND STALL OVER THE SOUTHERN WATERS WED AFTERNOON...MAKING WIND DIRECTIONS CHALLENGING. WSW WINDS WILL START OFF WED...THEN VEERING NORTH OF LOOKOUT THROUGH THE DAY BECOMING NORTHERLY 5-15KT BEHIND THE BOUNDARY AND SW AHEAD OF IT. LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 335 PM TUESDAY...A WEAK FRONTAL BOUNDARY WILL SHIFT WELL OFFSHORE WEDNESDAY NIGHT WITH WINDS BECOMING SOUTHEASTERLY LATE, 10 KNOTS OR LESS WITH SEAS GENERALLY 1-3 FT. HIGH PRESSURE OFFSHORE AND WEAK TROUGH DEVELOPING INLAND THURSDAY WILL RESULT IN SOUTHWESTERLY WINDS 10-20 KT WITH SEAS 3-5 FT THURSDAY EVENING INTO THURSDAY NIGHT, AND MAY SEE A FEW 6 FT SEAS FOR THE OUTER PORTIONS OF THE CENTRAL AND SOUTHERN WATERS. SMALL CRAFT ADVISORY CONDITIONS WILL BE POSSIBLE FRIDAY AND FRIDAY EVENING FOR THE CENTRAL AND SOUTHERN WATERS DUE TO WINDS GUSTING NEAR 25 KT AND SEAS UP TO 6 FT. A BACKDOOR COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE FRIDAY AND MOVE INTO THE EASTERN NC COASTAL WATERS SATURDAY, CREATING A COMPLEX WINDS/SEAS FORECAST HIGHLY DEPENDENT ON THE LOCATION OF THIS FRONTAL FEATURE. MAY SEE NORTHEASTERLY WINDS FOR THE ALBEMARLE SOUND AND COASTAL WATERS NORTH OF OREGON INLET SATURDAY NIGHT, THEN THE FRONT IS FORECAST TO SLOWLY SHIFT SOUTH SUNDAY AND OFF THE COAST BY SUNDAY EVENING/NIGHT WITH NORTH TO NORTHEASTERLY WINDS 10-15 KT OVERSPREADING THE EASTERN NC COASTAL WATERS SUNDAY NIGHT THROUGH MONDAY. THE FRONT SHIFTS WELL OFFSHORE MONDAY NIGHT INTO TUESDAY ALLOWING WINDS TO SHIFT EAST THEN SOUTHEASTERLY DURING THE DAY TUESDAY. SEAS WILL BUILD UP TO 6 FT FOR THE OUTER FRINGES OF THE COASTAL WATERS THIS WEEKEND THEN SLOWLY DIMINISH TO 3-5 FT LATE SUNDAY INTO MONDAY. LOCAL SWAN/NWPS AND WAVEWATCH IN GOOD AGREEMENT FOR THE MEDIUM RANGE THEN WAVEWATCH APPEARS REASONABLE FOR THE EXTENDED PERIOD. && .CLIMATE... RECORD HIGH TEMPERATURES TUESDAY: 6/23 LOCATION-----TEMP/YEAR--NOTES NEW BERN 98/1988 (KEWN ASOS) HATTERAS 88/1996 (KHSE ASOS) GREENVILLE 100/1933 (COOP - NOT KPGV ASOS) MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS) KINSTON 102/1911 (COOP - NOT KISO ASOS) JACKSONVILLE 99/2010 (KNCA AWOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047- 079>081-090>095-098-103. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT WEDNESDAY FOR AMZ135. SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM EDT WEDNESDAY FOR AMZ150. SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY FOR AMZ152-154- 156. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT WEDNESDAY FOR AMZ158. && $$ SYNOPSIS...CQD/HSA NEAR TERM...CQD SHORT TERM...CQD LONG TERM...DAG AVIATION...DAG/BM MARINE...CQD/DAG CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS RALEIGH NC
315 PM EDT TUE JUN 23 2015 .SYNOPSIS...HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS TO PERSIST ACROSS CENTRAL NC FOR THE NEXT SEVERAL DAYS BEFORE A DEEPENING UPPER LEVEL TROUGH WILL BRING COOLER AND WETTER CONDITIONS FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM TUESDAY... CURRENT SURFACE ANALYSIS SHOWS A COLD FRONT DRAPED ACROSS THE OHIO VALLEY AND A SURFACE TROUGH ENTERING THE NW PIEDMONT WHICH IS STARTING TO FIRE SOME SHOWERS OFF AS OF LAST HOUR. OTHERWISE HIGH PRESSURE OVER THE AREA HAS KEPT CONDITIONS HOT AND HUMID WITH HEAT ADVISORY ISSUED FROM HIGHWAY 1 EASTWARD. FOR RIGHT NOW THE VERIFICATION FOR THIS ADVISORY LOOKS GOOD WITH MOST SITES IN THE ADVISORY SEEING MULTIPLE HOURS OF 105-109 DEGREE HEAT INDICES WITH SOME JUST TOUCHING THE 110 DEGREE MARK. OUTSIDE OF THE ADVISORY...CONDITIONS HAVE LARGELY REMAINED BELOW ADVISORY CRITERIA WITH RDU AND SOUTHERN PINES JUST TOUCHING IT BUT YET TO BE DETERMINED IF IT WILL REMAIN THERE FOR THE NEXT SEVERAL HOURS AS SHORT TERM MODELS SHOW A REDUCTION IN HUMIDITY POSSIBLE IN THE VERY NEAR TERM. ADVISORY WILL REMAIN OUT UNTIL 7 PM WITH NO FURTHER CHANGES ANTICIPATED. AS FAR AS CONVECTION IS CONCERNED IN THE NW PIEDMONT THIS AFTERNOON THE FOCUS WILL BE ON THE PIEDMONT TROUGH WITH LOW LEVEL LAPSE RATES EXTREMELY FAVORABLE FOR DEVELOPMENT GIVEN THE HIGH TEMPERATURES BUT MID-LEVEL LAPSE RATES ONLY 5.5-6 DEG/KM AT THIS TIME. DESPITE THAT...SOME MID LEVEL DRY AIR HAS BROUGHT DCAPE VALUES UP TO AROUND 1200 J/KG AND SO SOME STRONGER WIND GUSTS ARE NOT OUT OF THE QUESTION IN THESE CELLS. WHILE NOT ANTICIPATING SEVERE WEATHER...SOME 30-40 MPH GUSTS ARE POSSIBLE. SHEAR VALUES OVER THE AREA ARE NON-EXISTENT HOWEVER AND NOT VERY FAVORABLE FOR SUSTAINED ACTIVITY. A BETTER CHANCE FOR CONVECTION ACROSS THE NW PIEDMONT AND PERHAPS INTO THE TRIANGLE AREA WILL BE WITH THE SURFACE COLD FRONT MOVING DOWN FROM THE NW AFTER 00Z. MODELS ARE PICKING UP ON A LINE OF CONVECTION THAT COULD PERSIST ACROSS THE I-40 CORRIDOR WEST OF RALEIGH UNTIL ABOUT 7Z OR SO BEFORE DYING OUT. THE RAP MODEL AND TO A LESSER EXTENT THE NAM ARE ALSO PICKING UP ON AN UPPER LEVEL VORT MAX TRAVELING SOUTHWESTWARD ALONG THE FRONT AND BEING A CATALYST FOR SOME STRONGER CONVECTION. THIS QUICKLY MOVES THROUGH AND DIMINISHES AFTER 6Z AND THE FRONT WILL BEGIN TO STALL OUT OVER THE AREA...PROBABLY NOT MAKING IT AS FAR SOUTH AS FAYETTEVILLE. WHILE WIDESPREAD CONVECTION IS AGAIN NOT ANTICIPATED...CONDITIONS ARE POTENTIALLY FAVORABLE FOR A SEVERE STORM OR TWO WHICH CORRELATES WELL WITH THE MARGINAL RISK ISSUED BY THE STORM PREDICTION CENTER FOR OUR AREA WITH A 5% CHANCE OF DAMAGING WINDS THE ONLY THREAT TO THE AREA. LOWS GENERALLY IN THE MID TO UPPER 70S NW TO SE OVERNIGHT. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 300 PM TUESDAY... WITH THE STALLED OUT FRONT ACROSS THE AREA THERE WONT BE TOO MUCH MODIFICATION IN THE AIRMASS AS FAR AS TEMPERATURES ARE CONCERNED SO IT WILL STILL BE HOT BUT NOT QUITE AS BAD AS THE LAST FEW DAYS WITH HIGHS EXPECTED TO TOP OUT IN THE MID TO UPPER 90S WITH HIGHEST TEMPS IN THE SOUTHWEST. THIS COUPLED WITH SLIGHTLY LOWER DEWPOINTS...ESPECIALLY ACROSS THE NORTH...WILL LEAD TO APPARENT TEMPS TOPPING OUT IN THE UPPER 90S ACROSS THE NORTH AND LOWER 100S IN THE SOUTH. THEREFORE NO HEAT ADVISORY IS ANTICIPATED FOR ANYWHERE IN THE CWA ON WEDNESDAY AND THIS WILL SIGNIFY THE VERY BEGINNING OF WHAT WILL BE A CHANGE IN PATTERN THAT SHOULD BRING COOLER AND WETTER CONDITIONS INTO THE AREA BY THE WEEKEND. DIURNAL CONVECTION WILL BE SUPPRESSED ACROSS THE EXTREME SOUTH OR MAYBE SOUTHEAST OF THE CWA WITH THE EXACT BOUNDARY DETERMINED BY THE SOUTHWARD PROGRESSION OF THE FRONT BUT IN GENERAL EXPECT SOME CLOUD COVER BUT A FAIRLY DRY DAY. LOWS WEDNESDAY NIGHT IN THE LOWER 70S. && .LONG TERM /THURSDAY THROUGH TUESDAY/... AS OF 315 PM TUESDAY... THE UPPER LEVEL PATTERN WILL SHIFT FROM THAT OF HIGH PRESSURE OVER THE SE U.S. AND ZONAL FLOW TO THE NORTH...TO MORE OF A TROUGH OVER THE EASTERN U.S. AND HIGH PRESSURE OVER THE WEST. INITIALLY...THE TROUGH WILL BE ORIENTED ALMOST WEST TO EAST THURSDAY NIGHT AND FRIDAY. WITH THE RIDGE LINGERING...THURSDAY AND FRIDAY SHOULD BE THE LAST OF THE HOT DAYS...HIGHS IN THE MID 90S AND LOWS IN THE LOW TO MID 70S. THE UPPER LEVEL TROUGH WILL BECOME MORE SW-NE ORIENTED OVER THE WEEKEND. MEANWHILE AT THE SURFACE...GENERAL LOW PRESSURE WITH CONTINUED WARM SW FLOW WILL PERSIST INTO THE WEEKEND BEFORE A BACKDOOR COLD FRONT PUSHES SOUTHWARD INTO CENTRAL NC. CONVECTIVE CHANCES AND PRECIP AMOUNTS WILL INCREASE THROUGH THE WEEKEND... PEAKING SOMEWHERE BETWEEN FRIDAY NIGHT AND SATURDAY NIGHT...AS THE FRONT APPROACHES AND MOVES THROUGH THE AREA...DECREASING THEREAFTER. CONFIDENCE IS GRADUALLY INCREASING WITH RESPECT TO CONVECTIVE CHANCES/TIMING/COVERAGE...HOWEVER IT IS STILL NOT TERRIBLY HIGH. BEHIND THE FRONT...GENERAL RIDGING AND NE FLOW WILL TAKE OVER... RESULTING IN TEMPERATURES SIGNIFICANTLY LOWER THAN THEY HAVE BEEN... WITH HIGHS LIKELY BELOW 90 DEGREES FOR THE FIRST TIME IN NEARLY 2 WEEKS. TEMPERATURES SHOULD BOTTOM OUT ON SUNDAY...HIGHS IN THE LOW TO MID 80S AND LOWS IN THE LOW TO MID 60S...REBOUNDING BACK INTO THE MID TO UPPER 80S FOR HIGHS ON TUESDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 200 PM TUESDAY... 24 HOUR TAF PERIOD: FAIRLY GOOD CHANCE OF VFR CONDITIONS THROUGH THE TAF PERIOD IN THE EAST BUT SOME QUESTIONS REMAIN IN THE TRIAD AND POSSIBLY KRDU AS HIGH RESOLUTION MODELS ARE DEPICTING SHOWER AND THUNDERSTORM ACTIVITY BETWEEN 00Z AND 06Z. DURING THIS TIME SOME VISIBILITY RESTRICTIONS DUE TO HEAVY RAIN COULD BE POSSIBLE AS WELL AS SOME LOWER CEILINGS BUT MOSTLY MVFR. OTHERWISE SOME GUSTY WINDS OF 15-20 KTS COULD BE POSSIBLE AT ALL SITES THIS AFTERNOON WITH MOSTLY CLEAR SKIES. AFTER OVERNIGHT CONVECTION CONCLUDES...EXPECT VFR CONDITIONS THROUGH THE END OF THE TAF PERIOD WITH SCATTERED CLOUDS AND WINDS TAKING ON A MORE WESTERLY COMPONENT. LONG TERM: A DEEPENING UPPER LEVEL TROUGH AND ACCOMPANYING SURFACE LOW PRESSURE WAVES WILL INCREASE CHANCES FOR CONVECTION AND THUS SUB- VFR CONDITIONS. ADVERSE CONDITIONS HIGHLY LIKELY FOR THE WEEKEND. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...ELLIS NEAR TERM...ELLIS SHORT TERM...ELLIS LONG TERM...RAH AVIATION...ELLIS CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
304 PM EDT TUE JUN 23 2015 .SYNOPSIS...HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS TO PERSIST ACROSS CENTRAL NC FOR THE NEXT SEVERAL DAYS BEFORE A DEEPENING UPPER LEVEL TROUGH WILL BRING COOLER AND WETTER CONDITIONS FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM TUESDAY... CURRENT SURFACE ANALYSIS SHOWS A COLD FRONT DRAPED ACROSS THE OHIO VALLEY AND A SURFACE TROUGH ENTERING THE NW PIEDMONT WHICH IS STARTING TO FIRE SOME SHOWERS OFF AS OF LAST HOUR. OTHERWISE HIGH PRESSURE OVER THE AREA HAS KEPT CONDITIONS HOT AND HUMID WITH HEAT ADVISORY ISSUED FROM HIGHWAY 1 EASTWARD. FOR RIGHT NOW THE VERIFICATION FOR THIS ADVISORY LOOKS GOOD WITH MOST SITES IN THE ADVISORY SEEING MULTIPLE HOURS OF 105-109 DEGREE HEAT INDICES WITH SOME JUST TOUCHING THE 110 DEGREE MARK. OUTSIDE OF THE ADVISORY...CONDITIONS HAVE LARGELY REMAINED BELOW ADVISORY CRITERIA WITH RDU AND SOUTHERN PINES JUST TOUCHING IT BUT YET TO BE DETERMINED IF IT WILL REMAIN THERE FOR THE NEXT SEVERAL HOURS AS SHORT TERM MODELS SHOW A REDUCTION IN HUMIDITY POSSIBLE IN THE VERY NEAR TERM. ADVISORY WILL REMAIN OUT UNTIL 7 PM WITH NO FURTHER CHANGES ANTICIPATED. AS FAR AS CONVECTION IS CONCERNED IN THE NW PIEDMONT THIS AFTERNOON THE FOCUS WILL BE ON THE PIEDMONT TROUGH WITH LOW LEVEL LAPSE RATES EXTREMELY FAVORABLE FOR DEVELOPMENT GIVEN THE HIGH TEMPERATURES BUT MID-LEVEL LAPSE RATES ONLY 5.5-6 DEG/KM AT THIS TIME. DESPITE THAT...SOME MID LEVEL DRY AIR HAS BROUGHT DCAPE VALUES UP TO AROUND 1200 J/KG AND SO SOME STRONGER WIND GUSTS ARE NOT OUT OF THE QUESTION IN THESE CELLS. WHILE NOT ANTICIPATING SEVERE WEATHER...SOME 30-40 MPH GUSTS ARE POSSIBLE. SHEAR VALUES OVER THE AREA ARE NON-EXISTENT HOWEVER AND NOT VERY FAVORABLE FOR SUSTAINED ACTIVITY. A BETTER CHANCE FOR CONVECTION ACROSS THE NW PIEDMONT AND PERHAPS INTO THE TRIANGLE AREA WILL BE WITH THE SURFACE COLD FRONT MOVING DOWN FROM THE NW AFTER 00Z. MODELS ARE PICKING UP ON A LINE OF CONVECTION THAT COULD PERSIST ACROSS THE I-40 CORRIDOR WEST OF RALEIGH UNTIL ABOUT 7Z OR SO BEFORE DYING OUT. THE RAP MODEL AND TO A LESSER EXTENT THE NAM ARE ALSO PICKING UP ON AN UPPER LEVEL VORT MAX TRAVELING SOUTHWESTWARD ALONG THE FRONT AND BEING A CATALYST FOR SOME STRONGER CONVECTION. THIS QUICKLY MOVES THROUGH AND DIMINISHES AFTER 6Z AND THE FRONT WILL BEGIN TO STALL OUT OVER THE AREA...PROBABLY NOT MAKING IT AS FAR SOUTH AS FAYETTEVILLE. WHILE WIDESPREAD CONVECTION IS AGAIN NOT ANTICIPATED...CONDITIONS ARE POTENTIALLY FAVORABLE FOR A SEVERE STORM OR TWO WHICH CORRELATES WELL WITH THE MARGINAL RISK ISSUED BY THE STORM PREDICTION CENTER FOR OUR AREA WITH A 5% CHANCE OF DAMAGING WINDS THE ONLY THREAT TO THE AREA. LOWS GENERALLY IN THE MID TO UPPER 70S NW TO SE OVERNIGHT. && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 300 PM TUESDAY... WITH THE STALLED OUT FRONT ACROSS THE AREA THERE WONT BE TOO MUCH MODIFICATION IN THE AIRMASS AS FAR AS TEMPERATURES ARE CONCERNED SO IT WILL STILL BE HOT BUT NOT QUITE AS BAD AS THE LAST FEW DAYS WITH HIGHS EXPECTED TO TOP OUT IN THE MID TO UPPER 90S WITH HIGHEST TEMPS IN THE SOUTHWEST. THIS COUPLED WITH SLIGHTLY LOWER DEWPOINTS...ESPECIALLY ACROSS THE NORTH...WILL LEAD TO APPARENT TEMPS TOPPING OUT IN THE UPPER 90S ACROSS THE NORTH AND LOWER 100S IN THE SOUTH. THEREFORE NO HEAT ADVISORY IS ANTICIPATED FOR ANYWHERE IN THE CWA ON WEDNESDAY AND THIS WILL SIGNIFY THE VERY BEGINNING OF WHAT WILL BE A CHANGE IN PATTERN THAT SHOULD BRING COOLER AND WETTER CONDITIONS INTO THE AREA BY THE WEEKEND. DIURNAL CONVECTION WILL BE SUPPRESSED ACROSS THE EXTREME SOUTH OR MAYBE SOUTHEAST OF THE CWA WITH THE EXACT BOUNDARY DETERMINED BY THE SOUTHWARD PROGRESSION OF THE FRONT BUT IN GENERAL EXPECT SOME CLOUD COVER BUT A FAIRLY DRY DAY. LOWS WEDNESDAY NIGHT IN THE LOWER 70S. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 200 PM TUESDAY... 24 HOUR TAF PERIOD: FAIRLY GOOD CHANCE OF VFR CONDITIONS THROUGH THE TAF PERIOD IN THE EAST BUT SOME QUESTIONS REMAIN IN THE TRIAD AND POSSIBLY KRDU AS HIGH RESOLUTION MODELS ARE DEPICTING SHOWER AND THUNDERSTORM ACTIVITY BETWEEN 00Z AND 06Z. DURING THIS TIME SOME VISIBILITY RESTRICTIONS DUE TO HEAVY RAIN COULD BE POSSIBLE AS WELL AS SOME LOWER CEILINGS BUT MOSTLY MVFR. OTHERWISE SOME GUSTY WINDS OF 15-20 KTS COULD BE POSSIBLE AT ALL SITES THIS AFTERNOON WITH MOSTLY CLEAR SKIES. AFTER OVERNIGHT CONVECTION CONCLUDES...EXPECT VFR CONDITIONS THROUGH THE END OF THE TAF PERIOD WITH SCATTERED CLOUDS AND WINDS TAKING ON A MORE WESTERLY COMPONENT. LONG TERM: A DEEPENING UPPER LEVEL TROUGH AND ACCOMPANYING SURFACE LOW PRESSURE WAVES WILL INCREASE CHANCES FOR CONVECTION AND THUS SUB- VFR CONDITIONS. ADVERSE CONDITIONS HIGHLY LIKELY FOR THE WEEKEND. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...ELLIS NEAR TERM...ELLIS SHORT TERM...ELLIS LONG TERM...WSS AVIATION...ELLIS CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS RALEIGH NC
207 PM EDT TUE JUN 23 2015 .SYNOPSIS...HIGH PRESSURE ALOFT WILL CAUSE HOT CONDITIONS TO PERSIST ACROSS CENTRAL NC FOR THE NEXT SEVERAL DAYS BEFORE A DEEPENING UPPER LEVEL TROUGH WILL BRING COOLER AND WETTER CONDITIONS FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM TUESDAY... MORNING UPDATE: TEMPERATURES ON TRACK FOR UPPER 90S TODAY WITH A FEW SPOTS TOUCHING THE HUNDRED DEGREE MARK. AS OF 1000 AM...MOST LOCATIONS IN THE MID 80S ALREADY WITH HEAT INDICES IN THE LOW 90S. MAY BE HARD TO REACH THE 105 DEGREE HEAT ADVISORY CRITERIA TODAY IN MOST SPOTS BUT WITH VERY PERSISTENT HEAT THE LAST SEVERAL DAYS AND LIKELY HEAT INDICES BETWEEN 100-105 DEGREES...HAVE A HEAT ADVISORY IN EFFECT FROM NOON UNTIL 700 PM FOR POINTS EAST OF HIGHWAY 1. A SURFACE TROUGH IS ALSO SETTING UP RIGHT ALONG HIGHWAY 1. TO THE EAST OF HERE...MOISTURE WILL BE HIGHER AND THUS THE HIGHER HEAT INDICES. THIS AREA COULD BE A FOCUS FOR SOME DIURNAL CONVECTION AS WELL WHICH WE WILL MONITOR FOR THIS AFTERNOON. PREVIOUS DISCUSSION FOLLOWS. -ELLIS MID LEVEL HEIGHTS WILL INCREASE A BIT MORE TODAY... WITH AFTERNOON LOW LEVEL THICKNESS VALUES EXPECTED TO BE AROUND 7 TO 8 METERS HIGHER TODAY. THUS... GIVEN SIMILAR CONDITIONS EXPECT WE SHOULD SEE HIGH TEMPS GENERALLY 2-3 DEGREES WARMER THAN YESTERDAY FOR MOST LOCATIONS. THIS SHOULD RESULT IN HIGH TEMPS IN THE UPPER 90S TO NEAR 100 DEGREES ACROSS THE AREA. THIS COMBINED WITH DEWPOINTS IN THE UPPER 60S TO LOWER 70S ACROSS THE EASTERN AND SOUTHEASTERN PORTIONS OF THE AREA SHOULD RESULT IN SEVERAL HOURS OF HEAT INDEX VALUES THIS AFTERNOON OF AROUND 105 DEGREES OR HIGHER. THUS... CURRENT HEAT ADVISORY LOOKS GOOD WITH NO CHANGES PLANNED AT THIS TIME. IN ADDITION TO THE HEAT... WE MAY SEE SOME AFTERNOON SHOWERS AND STORMS DEVELOP ALONG A REMNANT OUTFLOW AND MCV THAT IS CURRENTLY SINKING SOUTH AND EASTWARD INTO THE FA. THE LATEST RAP SHOWS THIS FEATURE SLOWLY SHIFTING SOUTH AND EASTWARD ACROSS CENTRAL NC THIS MORNING... WITH POSSIBLY A FEW WEAK SHOWERS DEVELOPING ALONG IT (NOTHING CURRENTLY ON RADAR). HOWEVER... AS THE FEATURE SHIFTS EASTWARD ACROSS THE AREA LATER TODAY... THINK WE MAY SEE SOME DEVELOPMENT ACROSS OUR SOUTHEASTERN/EASTERN COUNTIES... WHICH IS LOOSELY SHOWN BY SOME OF THE HIGH-RES GUIDANCES. GIVEN MODERATE INSTABILITY (IF WE INDEED GET SOME STORMS TO DEVELOP) WE COULD SEE A FEW STRONG TO PERHAPS SEVERE STORMS... MAINLY PULSE IN NATURE GIVEN CONTINUED WEAK DEEP LAYER SHEAR. THE NEXT FEATURE OF INTERESTED TODAY INTO THIS EVENING WILL BE THE APPROACH OF A COLD FRONT AND A CLUSTER OR LINE OF SHOWERS AND STORMS IN ADVANCE OF THE FRONT. SOME OF THE HI-RES (CAM`S) GUIDANCES SHOWS THIS LINE/DEVELOPMENT ALONG OUTFLOW MAKING IT INTO OUR AREA LATE TODAY INTO THIS EVENING. WHICH SEEMS POSSIBLE GIVEN THE EXPECTED NOCTURNAL RECOVERY OF DEWPOINTS AND RESULTANT CONTINUATION OF DECENT INSTABILITY. THUS... HAVE INCREASED POPS ACROSS THE NORTH/NORTHWESTERN HALF OF THE CWA FOR LATE TODAY INTO THE EVENING... WITH THE CONVECTION POSSIBLY LINGERING INTO THE EARLY MORNING HOURS OF WEDNESDAY. IF WE DO SEE SOME OF THIS ACTIVITY MAKING IT INTO OUR AREA EXPECT WE COULD SEE SOME ADDITIONAL STRONG TO SEVERE STORMS... WITH THE MAIN THREAT FROM DAMAGING WINDS. EXPECT THE ACTUAL COLD FRONT TO SINK SOUTHWARD AND INTO THE AREA NEAR 12Z WEDNESDAY. HOWEVER... EXPECT OVERNIGHT LOWS SHOULD REMAIN QUITE UNCOMFORTABLE... GENERALLY RANGING FROM THE LOWER TO UPPER 70S. -77 && .SHORT TERM /WEDNESDAY AND WEDNESDAY NIGHT/... AS OF 320 AM TUESDAY... THE LATEST GFS AND ECMWF ARE IN GENERAL AGREEMENT ON SHOWING THE SURFACE FRONT SETTLE SOUTH AND EASTWARD INTO SOUTHEASTERN PORTIONS OF CENTRAL NC. THUS... EXPECT THE BEST CHANCE OF SHOWERS AND STORMS WEDNESDAY AFTERNOON AND EVENING WILL BE ACROSS THE COASTAL PLAIN AND SANDHILLS... GENERALLY SOUTH AND EAST OF RALEIGH. HIGH TEMPS ON WEDNESDAY ARE EXPECTED TO RANGE FROM THE LOWER 90S/NEAR 90 NORTH TO THE MID TO UPPER 90S SOUTH. OVERNIGHT LOWS WEDNESDAY NIGHT SHOULD RANGE FROM NEAR 70 NORTH TO THE MID 70S SOUTHEAST. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... UPPER AIR PATTERN UNDERGOES A MAJOR SHIFT ACROSS THE U.S. A STRONG UPPER LEVEL RIDGE IS PROJECTED TO AMPLIFY OVER THE WESTERN U.S. THIS WILL FORCE THE JET STREAM TO DIVE SEWD ACROSS THE NORTHERN PLAINS AND GREAT LAKES STATES...DIMINISHING THE PERSISTENT UPPER RIDGE OVER THE SE U.S....AND REPLACING IT WITH A L/W TROUGH BY THE WEEKEND. THIS TRANSFORMATION WILL BRING AN END TO OUR CURRENT STRETCH OF WELL ABOVE NORMAL TEMPS. THIS TRANSITION EXPECTED TO TAKE PLACE FRIDAY THROUGH SUNDAY. PRIOR TO THAT...EXPECT ANOTHER HOT AFTERNOON THURSDAY WITH A THREAT FOR AFTERNOON CONVECTION...MAINLY ACROSS THE SOUTH AND EAST SECTIONS OF THE CWA AS A WEAK SFC TROUGH WILL LINGER IN THIS VICINITY. THIS FEATURE WILL ACT AS A FOCUS FOR MOISTURE POOLING AND AID TO INITIATE/SUSTAIN CONVECTIVE DEVELOPMENT. EXPECT THE STRONGER STORMS TO PRODUCE WIND GUSTS 35-45 MPH ALONG WITH FREQUENT-EXCESSIVE LIGHTNING. THE LEAD S/W THAT WILL AID TO INITIATE THE THE L/W TROUGH FORMATION WILL APPROACH FROM THE NW FRIDAY AND AFFECT OUR REGION FRIDAY NIGHT INTO SATURDAY. THIS PERIOD WILL FEATURE THE HIGHEST THREAT FOR SHOWERS AND STORMS. FOR NOW WILL CAP POP AT 50 PERCENT THOUGH IF MODEL GUIDANCE REMAINS CONSISTENT...HIGHER POPS WILL BE WARRANTED. EXPECT FRIDAY WILL BE THE LAST DAY WITH TEMPS WELL INTO THE 90S. HOWEVER...IF CLOUD COVERAGE MORE EXTENSIVE THAN CURRENT THINKING OR IF CONVECTION DEVELOPS SOONER THAN MID-LATE AFTERNOON...THEN HIGH TEMPS FRIDAY MAY END UP BEING 5-6 DEGREES COOLER THAN FORECAST. EXTENSIVE CLOUDINESS SATURDAY AND SCATTERED SHOWERS AND STORMS WILL RESULT IN TEMPS CLOSER TO NORMAL (85-90). SOME MODEL GUIDANCE SUGGESTING MUCH COOLER CONDITIONS SUNDAY AS POTENTIAL COLD AIR DAMMING SCENARIO MAY OCCUR. HOWEVER A COUPLE OF SIGNALS ARE MISSING FOR A TYPICAL CAD SET-UP...NAMELY THE SFC HIGH IS NOT IN A FAVORABLE ORIENTATION NOR OF SUFFICIENT STRENGTH. FOR NOW WILL IGNORE GUIDANCE THAT IS ADVERTISING MAX TEMPS IN THE PIEDMONT BELOW 80 DEGREES AND FAVOR MAX TEMPS IN THE LOW-MID 80S. SCATTERED CONVECTION STILL A THREAT SUNDAY...MAINLY ACROSS THE SANDHILLS AND COASTAL PLAIN ALONG A TRAILING SFC TROUGH. A MORE STABLE DRIER AIR EXPECTED TO OVERSPREAD THE REGION SUNDAY NIGHT INTO MONDAY. THE LESS HUMID AIR MASS WILL BE A WELCOME CHANGE. MAX TEMPS EARLY NEXT WEEK MAY BE 3-5 DEGREES BELOW NORMAL WITH MAX TEMPS IN THE LOW-MID 80S. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 200 PM TUESDAY... 24 HOUR TAF PERIOD: FAIRLY GOOD CHANCE OF VFR CONDITIONS THROUGH THE TAF PERIOD IN THE EAST BUT SOME QUESTIONS REMAIN IN THE TRIAD AND POSSIBLY KRDU AS HIGH RESOLUTION MODELS ARE DEPICTING SHOWER AND THUNDERSTORM ACTIVITY BETWEEN 00Z AND 06Z. DURING THIS TIME SOME VISIBILITY RESTRICTIONS DUE TO HEAVY RAIN COULD BE POSSIBLE AS WELL AS SOME LOWER CEILINGS BUT MOSTLY MVFR. OTHERWISE SOME GUSTY WINDS OF 15-20 KTS COULD BE POSSIBLE AT ALL SITES THIS AFTERNOON WITH MOSTLY CLEAR SKIES. AFTER OVERNIGHT CONVECTION CONCLUDES...EXPECT VFR CONDITIONS THROUGH THE END OF THE TAF PERIOD WITH SCATTERED CLOUDS AND WINDS TAKING ON A MORE WESTERLY COMPONENT. LONG TERM: A DEEPENING UPPER LEVEL TROUGH AND ACCOMPANYING SURFACE LOW PRESSURE WAVES WILL INCREASE CHANCES FOR CONVECTION AND THUS SUB- VFR CONDITIONS. ADVERSE CONDITIONS HIGHLY LIKELY FOR THE WEEKEND. && .CLIMATE... REC DAY MAX YR RDU RECORDS 06/23 100 1986 06/24 99 2010 06/25 100 1952 GSO RECORDS 06/23 102 1914 06/24 103 1914 06/25 101 1914 FAY RECORDS 06/23 102 1981 06/24 102 1914 06/25 102 1914 && .RAH WATCHES/WARNINGS/ADVISORIES... HEAT ADVISORY FROM NOON TO 7 PM EDT THIS EVENING FOR NCZ011-027-028-042-043-077-078-085-086-088-089. && $$ SYNOPSIS...ELLIS NEAR TERM...ELLIS/77 SHORT TERM...77 LONG TERM...WSS AVIATION...ELLIS CLIMATE...RAH
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
142 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...BECOME STATIONARY AND LINGER IN THE AREA THROUGH THE WEEKEND. IT WILL FINALLY MOVE OFF THE COAST EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1220 PM TUE...HEAT AND HUMIDITY CONTINUES TODAY...WITH BERMUDA HIGH EXTENDING OVER THE AREA FROM OFFSHORE AND TROUGHING INLAND. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 20-22C SUPPORT HIGHS IN THE LOW TO UPPER 90S. HOT TEMPS COMBINED WITH DEWPOINTS IN THE 70S WILL AGAIN RESULT IN ADV CRITERIA. HEAT ADVISORY CONTINUES ALL COUNTIES EXCEPT OUTER BANKS HYDE...WITH HEAT INDEX VALUES 105-110 THIS AFTERNOON. ISOLATED TO SCATTERED SEABREEZE SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON...PER NSSL WRF AND HRRR. EXPECT MOST CONVECTION TO WANE WITH LOSS OF HEATING EARLY THIS EVENING. THEN COULD SEE ADDITIONAL CONVECTION MOVE INTO THE NORTHERN TIER FROM THE NW AHEAD OF THE APPROACHING FRONTAL BOUNDARY. NSSL WRF AND HRRR SHOW A LINE MOVING IN BTWN 00-06Z TONIGHT...THOUGH WEAKENING AS IT MOVES SE INTO NE NC. AN ISOLATED STRONG TSTM WITH GUSTY WINDS WILL BE POSSIBLE THIS AFTERNOON AND EVENING. && .SHORT TERM /WEDNESDAY/... AS OF 345 AM TUE...AFTERNOON CONVECTION WILL DISSIPATE EARLY EVENING WITH LOSS OF DAYTIME HEATING. FRONTAL BOUNDARY WILL APPROACH FROM THE NORTHWEST OVERNIGHT AND HAVE REINTRODUCED 20-30% POPS AFTER 06Z. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... AS OF 345 AM TUE...A GRADUAL PATTERN CHANGE IS EXPECTED BY MID/LATE WEEK AS THE HOT AND HUMID WEATHER IS REPLACED BY A BETTER CHANCE OF PRECIPITATION. WEDNESDAY/WEDNESDAY NIGHT...UPPER RIDGE WILL CONTINUE TO BE IN CONTROL FOR MUCH OF WEDNESDAY AND WITH HIGH TEMPERATURES AGAIN WELL INTO THE 90S OVER OUR SOUTHWESTERN ZONES...WILL LIKELY SEE HEAT INDICES IN THE 105-110 DEGREE RANGE AGAIN. AS A WEAK BACK DOOR FRONT DROPS SOUTH INTO OUR NORTHEASTERN COUNTIES LATE WEDNESDAY INTO WEDNESDAY NIGHT...EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS...HIGHEST NORTHEAST AREAS. THURSDAY/THURSDAY NIGHT...UPPER HEIGHTS FALL ON THURSDAY AS THE FRONTAL BOUNDARY SURGES BACK NORTH. WITH GOOD INSTABILITY...EXPECT A CHANCE OF THUNDERSTORMS AGAIN THURSDAY AFTERNOON INTO THURSDAY NIGHT. WITH MORE CLOUD COVER...TEMPERATURES WILL BE A DEGREE OR TWO COOLER...BUT WITH HIGH DEWPOINTS LINGERING...WILL STILL LIKELY SEE SOME HEAT INDEX VALUES AROUND 100 DEGREES. FRIDAY THROUGH SUNDAY...THE COMBINATION OF A STALLED FRONTAL BOUNDARY NEAR OR JUST NORTH OF THE CWA AND A CLOSED LOW FORMING OVER THE GREAT LAKES WILL LEAD TO A WETTER PATTERN FOR THE WEEKEND. MID-LEVEL TROUGH WILL DIG TO THE SOUTH AND EAST WITH TIME THROUGH THE WEEKEND TAPPING A GOOD FEED OF GULF MOISTURE. WILL CONTINUE PREVIOUS FORECAST TREND OF HIGH CHANCE POPS FRIDAY INTO SUNDAY. GUIDANCE SHOWING PRECIPITABLE WATER IN THE 2.0 TO 2.25 INCH RANGE SATURDAY INTO SUNDAY...SO SOME MUCH-NEEDED HEAVIER RAINFALL WILL BE POSSIBLE. HIGH TEMPERATURES WILL FALL INTO THE UPPER 80S OVER THE WEEKEND IN MANY SPOTS DUE TO MORE CLOUD COVER AND PRECIPITATION WITH LOWS IN THE LOW/MID 70S WITH MORE RAIN- COOLED AIR. MONDAY...AS THE UPPER LOW LIFTS OUT TO THE NORTHEAST...EXPECT DOWNSLOPING FLOW TO DRY THINGS OUT FOR EARLY NEXT WEEK. TEMPERATURES SHOULD BE NEAR CLIMATOLOGY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... SHORT TERM /THROUGH 18Z WEDNESDAY/... AS OF 120 PM TUESDAY...HIGH CONFIDENCE OF VFR CONDITIONS WILL PREVAIL FOR MOST OF THE TAF PERIOD. SURFACE HIGH PRESSURE EXTENDING OVER EASTERN NC FROM THE WESTERN ATLANTIC OCEAN AND TROUGH INLAND. EXPECT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS TO DEVELOP ALONG THE SEABREEZE THIS AFTERNOON. MOST OF THE SHOWERS/THUNDERSTORMS SHOULD WANE WITH THE LOSS OF HEATING EARLY THIS EVENING. OVERNIGHT...AN APPROACHING COLD FRONT FROM THE NORTHWEST COULD BRING VCTS/VCSH...BUT CONFIDENCE IS LOW TO ADD IN THE TAFS AS HI- RES MODELS ARE SHOWING THE RAIN WEAKENING AS ITS APPROACHING OUR AREA. PLUS...COULD SEE PATCHY FOG DEVELOP TOWARDS EARLY MORNING (APPROX. 10Z) AND THEREFORE ADDED 5SM FOR OUR INLAND TAF SITES (PGV/ISO). WINDS WILL BECOME LIGHT AND VARIABLE TOMORROW MORNING AS THE COLD FRONT CROSSES THE AREA UNDER SCATTERED CLOUDS AT 4KFT. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...VFR CONDITIONS WILL PREVAIL WEDNESDAY...BUT WILL BEGIN TO SEE MORE FREQUENT SUB-VFR CONDITIONS THURSDAY INTO THE WEEKEND...ESPECIALLY FRIDAY/SATURDAY AS PRECIPITATION COVERAGE INCREASES. WILL ALSO SEE SOME AREAS OF MVFR CEILINGS AND VSBYS WITH LATE NIGHT STRATUS AND FOG IN AREAS WHERE RAIN OCCURS LATE IN THE WEEK. && .MARINE... SHORT TERM /THROUGH TONIGHT/... AS OF 1220 PM TUE...SOUTHWEST FLOW CONTINUES IN THE SHORT TERM WITH THE BERMUDA HIGH IN PLACE. LATEST OBS SHOW SW WINDS 10-15KT AND SEAS 2-4FT. COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TONIGHT TIGHTENING THE PRESSURE GRADIENT...WITH WINDS INCREASING TO 15-25KT ACROSS MOST OF THE WATERS AND SOUNDS. UPDATED TO ADD SCA FOR NORTHERN WATERS. SCA UP FOR PAMLICO SOUND AND WATERS SOUTH OF OREGON INLET...FOR GUSTY WINDS AND BUILDING SEAS THIS AFTERNOON INTO EARLY WED MORNING. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...SOME GUSTY SW WINDS TO BEGIN THE DAY ON WEDNESDAY BUT THE GRADIENT RELAXES THROUGH THURSDAY WITH GENERALLY S/SW WINDS AT 10 KNOTS OR LESS. WITH A PERSISTENT LOW INLAND AND STRONG BERMUDA RIDGE OFFSHORE...THE GRADIENT TIGHTENS THURSDAY NIGHT THROUGH SATURDAY AS A STRONG UPPER LEVEL SYSTEMS MOVES ACROSS THE MID-ATLANTIC AND SOUTHEAST. WILL LIKELY SEE SW WINDS INCREASE TO 15 TO 20 KNOTS THURSDAY NIGHT AND FRIDAY AND UP TO 20 TO 25 KNOTS ON SATURDAY. PER LATEST WAVE MODELS...SEAS BUILDS TO 6 FEET OR GREATER FOR FRIDAY INTO SATURDAY. && .CLIMATE... RECORD HIGH TEMPERATURES TUESDAY: 6/23 LOCATION-----TEMP/YEAR--NOTES NEW BERN 98/1988 (KEWN ASOS) HATTERAS 88/1996 (KHSE ASOS) GREENVILLE 100/1933 (COOP - NOT KPGV ASOS) MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS) KINSTON 102/1911 (COOP - NOT KISO ASOS) JACKSONVILLE 99/2010 (KNCA AWOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047- 079>081-090>095-098-103. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT WEDNESDAY FOR AMZ135. SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM EDT WEDNESDAY FOR AMZ150. SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY FOR AMZ152-154- 156. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT WEDNESDAY FOR AMZ158. && $$ SYNOPSIS...CQD/HSA NEAR TERM...CQD SHORT TERM...CQD LONG TERM...DAG AVIATION...DAG/BM MARINE...CQD/DAG CLIMATE...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1221 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL APPROACH FROM THE NORTHWEST TONIGHT...BECOME STATIONARY AND LINGER IN THE AREA THROUGH THE WEEKEND. IT WILL FINALLY MOVE OFF THE COAST EARLY NEXT WEEK. && .NEAR TERM /TODAY/... AS OF 1220 PM TUE...HEAT AND HUMIDITY CONTINUES TODAY...WITH BERMUDA HIGH EXTENDING OVER THE AREA FROM OFFSHORE AND TROUGHING INLAND. LOW LEVEL THICKNESS VALUES AND 850MB TEMPS 20-22C SUPPORT HIGHS IN THE LOW TO UPPER 90S. HOT TEMPS COMBINED WITH DEWPOINTS IN THE 70S WILL AGAIN RESULT IN ADV CRITERIA. HEAT ADVISORY CONTINUES ALL COUNTIES EXCEPT OUTER BANKS HYDE...WITH HEAT INDEX VALUES 105-110 THIS AFTERNOON. ISOLATED TO SCATTERED SEABREEZE SHOWERS AND TSTMS EXPECTED TO DEVELOP THIS AFTERNOON...PER NSSL WRF AND HRRR. EXPECT MOST CONVECTION TO WANE WITH LOSS OF HEATING EARLY THIS EVENING. THEN COULD SEE ADDITIONAL CONVECTION MOVE INTO THE NORTHERN TIER FROM THE NW AHEAD OF THE APPROACHING FRONTAL BOUNDARY. NSSL WRF AND HRRR SHOW A LINE MOVING IN BTWN 00-06Z TONIGHT...THOUGH WEAKENING AS IT MOVES SE INTO NE NC. AN ISOLATED STRONG TSTM WITH GUSTY WINDS WILL BE POSSIBLE THIS AFTERNOON AND EVENING. && .SHORT TERM /TONIGHT/... AS OF 345 AM TUE...AFTERNOON CONVECTION WILL DISSIPATE EARLY EVENING WITH LOSS OF DAYTIME HEATING. FRONTAL BOUNDARY WILL APPROACH FROM THE NORTHWEST OVERNIGHT AND HAVE REINTRODUCED 20-30% POPS AFTER 06Z. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... AS OF 345 AM TUE...A GRADUAL PATTERN CHANGE IS EXPECTED BY MID/LATE WEEK AS THE HOT AND HUMID WEATHER IS REPLACED BY A BETTER CHANCE OF PRECIPITATION. WEDNESDAY/WEDNESDAY NIGHT...UPPER RIDGE WILL CONTINUE TO BE IN CONTROL FOR MUCH OF WEDNESDAY AND WITH HIGH TEMPERATURES AGAIN WELL INTO THE 90S OVER OUR SOUTHWESTERN ZONES...WILL LIKELY SEE HEAT INDICES IN THE 105-110 DEGREE RANGE AGAIN. AS A WEAK BACK DOOR FRONT DROPS SOUTH INTO OUR NORTHEASTERN COUNTIES LATE WEDNESDAY INTO WEDNESDAY NIGHT...EXPECT A CHANCE OF SHOWERS/THUNDERSTORMS...HIGHEST NORTHEAST AREAS. THURSDAY/THURSDAY NIGHT...UPPER HEIGHTS FALL ON THURSDAY AS THE FRONTAL BOUNDARY SURGES BACK NORTH. WITH GOOD INSTABILITY...EXPECT A CHANCE OF THUNDERSTORMS AGAIN THURSDAY AFTERNOON INTO THURSDAY NIGHT. WITH MORE CLOUD COVER...TEMPERATURES WILL BE A DEGREE OR TWO COOLER...BUT WITH HIGH DEWPOINTS LINGERING...WILL STILL LIKELY SEE SOME HEAT INDEX VALUES AROUND 100 DEGREES. FRIDAY THROUGH SUNDAY...THE COMBINATION OF A STALLED FRONTAL BOUNDARY NEAR OR JUST NORTH OF THE CWA AND A CLOSED LOW FORMING OVER THE GREAT LAKES WILL LEAD TO A WETTER PATTERN FOR THE WEEKEND. MID-LEVEL TROUGH WILL DIG TO THE SOUTH AND EAST WITH TIME THROUGH THE WEEKEND TAPPING A GOOD FEED OF GULF MOISTURE. WILL CONTINUE PREVIOUS FORECAST TREND OF HIGH CHANCE POPS FRIDAY INTO SUNDAY. GUIDANCE SHOWING PRECIPITABLE WATER IN THE 2.0 TO 2.25 INCH RANGE SATURDAY INTO SUNDAY...SO SOME MUCH-NEEDED HEAVIER RAINFALL WILL BE POSSIBLE. HIGH TEMPERATURES WILL FALL INTO THE UPPER 80S OVER THE WEEKEND IN MANY SPOTS DUE TO MORE CLOUD COVER AND PRECIPITATION WITH LOWS IN THE LOW/MID 70S WITH MORE RAIN- COOLED AIR. MONDAY...AS THE UPPER LOW LIFTS OUT TO THE NORTHEAST...EXPECT DOWNSLOPING FLOW TO DRY THINGS OUT FOR EARLY NEXT WEEK. TEMPERATURES SHOULD BE NEAR CLIMATOLOGY. && .AVIATION /16Z TUESDAY THROUGH SATURDAY/... SHORT TERM /THROUGH TONIGHT/... AS OF 7 AM TUE...PATCHY MVFR FOG THIS MORNING WILL BURN OFF QUICKLY AFTER SUNRISE. VFR CONDITIONS EXPECTED THROUGH THE PERIOD OUTSIDE OF CONVECTION. LITTLE CHANGE IN THE AIRMASS AND COULD SEE PATCHY MVFR FOG DEVELOP TOWARD EARLY MORNING AT ALL SITES. SOUTHWEST WIND PERSISTS THROUGH THE PERIOD. WINDS COULD GUST TO 15-20 KTS THIS AFTERNOON WITH ISOLATED AFTERNOON/EVENING THUNDERSTORMS AT ALL 4 TERMINALS. FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST TONIGHT SO ISOLATED CONVECTION STILL POSSIBLE OVERNIGHT TUESDAY INTO EARLY WEDNESDAY. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...VFR CONDITIONS WILL PREVAIL WEDNESDAY...BUT WILL BEGIN TO SEE MORE FREQUENT SUB-VFR CONDITIONS THURSDAY INTO THE WEEKEND...ESPECIALLY FRIDAY/SATURDAY AS PRECIPITATION COVERAGE INCREASES. WILL ALSO SEE SOME AREAS OF MVFR CEILINGS AND VSBYS WITH LATE NIGHT STRATUS AND FOG IN AREAS WHERE RAIN OCCURS LATE IN THE WEEK. && .MARINE... SHORT TERM /THROUGH TONIGHT/... AS OF 1220 PM TUE...SOUTHWEST FLOW CONTINUES IN THE SHORT TERM WITH THE BERMUDA HIGH IN PLACE. LATEST OBS SHOW SW WINDS 10-15KT AND SEAS 2-4FT. COLD FRONT WILL APPROACH FROM THE NORTHWEST LATE TONIGHT TIGHTENING THE PRESSURE GRADIENT...WITH WINDS INCREASING TO 15-25KT ACROSS MOST OF THE WATERS AND SOUNDS. UPDATED TO ADD SCA FOR NORTHERN WATERS. SCA UP FOR PAMLICO SOUND AND WATERS SOUTH OF OREGON INLET...FOR GUSTY WINDS AND BUILDING SEAS THIS AFTERNOON INTO EARLY WED MORNING. LONG TERM /WEDNESDAY THROUGH SATURDAY/... AS OF 345 AM TUESDAY...SOME GUSTY SW WINDS TO BEGIN THE DAY ON WEDNESDAY BUT THE GRADIENT RELAXES THROUGH THURSDAY WITH GENERALLY S/SW WINDS AT 10 KNOTS OR LESS. WITH A PERSISTENT LOW INLAND AND STRONG BERMUDA RIDGE OFFSHORE...THE GRADIENT TIGHTENS THURSDAY NIGHT THROUGH SATURDAY AS A STRONG UPPER LEVEL SYSTEMS MOVES ACROSS THE MID-ATLANTIC AND SOUTHEAST. WILL LIKELY SEE SW WINDS INCREASE TO 15 TO 20 KNOTS THURSDAY NIGHT AND FRIDAY AND UP TO 20 TO 25 KNOTS ON SATURDAY. PER LATEST WAVE MODELS...SEAS BUILDS TO 6 FEET OR GREATER FOR FRIDAY INTO SATURDAY. && .CLIMATE... RECORD HIGH TEMPERATURES TUESDAY: 6/23 LOCATION-----TEMP/YEAR--NOTES NEW BERN 98/1988 (KEWN ASOS) HATTERAS 88/1996 (KHSE ASOS) GREENVILLE 100/1933 (COOP - NOT KPGV ASOS) MOREHEAD CITY 95/1988 (COOP - NOT KMRH ASOS) KINSTON 102/1911 (COOP - NOT KISO ASOS) JACKSONVILLE 99/2010 (KNCA AWOS) && .MHX WATCHES/WARNINGS/ADVISORIES... NC...HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR NCZ029-044>047- 079>081-090>095-098-103. MARINE...SMALL CRAFT ADVISORY UNTIL 7 AM EDT WEDNESDAY FOR AMZ135. SMALL CRAFT ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM EDT WEDNESDAY FOR AMZ150. SMALL CRAFT ADVISORY UNTIL 10 AM EDT WEDNESDAY FOR AMZ152-154- 156. SMALL CRAFT ADVISORY FROM 8 PM THIS EVENING TO 8 AM EDT WEDNESDAY FOR AMZ158. && $$ SYNOPSIS...HSA NEAR TERM...CQD/HSA SHORT TERM...HSA LONG TERM...CTC AVIATION...CTC/HSA MARINE...CTC/CQD/HSA CLIMATE...MHX
AREA FORECAST DISCUSSION
NWS BISMARCK ND
549 PM CDT TUE JUN 23 2015 .UPDATE... ISSUED AT 543 PM CDT TUE JUN 23 2015 THE 19-21 UTC HRRR ITERATIONS HAVE A GOOD HANDLE ON THE ONGOING CONVECTION ACROSS WESTERN NORTH DAKOTA...AND WILL USE A BLEND OF THEIR SOLUTIONS FOR SKY COVER AND POPS THROUGH THE EVENING AND OVERNIGHT. A MARGINAL THREAT FOR LARGE HAIL AND DAMAGING WINDS WILL CONTINUE ACROSS SOUTHWEST AND POSSIBLY INTO SOUTH CENTRAL NORTH DAKOTA THROUGH SUNSET. THE 22 UTC RAP ANALYSIS DEPICTS STRONG DEEP LAYER SHEAR OF 40 KTS...WITH ML CAPE VALUES AROUND 1000-1500 J/KG...400 J/KG OF HAIL CAPE AND DOWNDRAFT CAPE AROUND 1000 J/KG. OVERALL...DEEPER MOISTURE APPEARS TO BE A MITIGATING FACTOR FOR GREATER STORM INTENSITY. MULTIPLE FUNNEL CLOUD REPORTS HAVE ALSO BEEN RECEIVED ACROSS THE SOUTHWEST GIVEN THE AT TIMES SUPERCELLUR NATURE OF THE STORMS. HOWEVER...LOW LEVEL KINEMATIC FIELDS ARE NOT OVERLY SUPPORTIVE OF TORNADOES. && .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 129 PM CDT TUE JUN 23 2015 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR THUNDERSTORMS THROUGH THE PERIOD...SOME MARGINALLY SEVERE SOUTHWEST THIS AFTERNOON/EVENING...AND ACROSS WESTERN AND CENTRAL NORTH DAKOTA WEDNESDAY. CURRENTLY...ACTIVE WEST-NORTHWEST FLOW ALOFT WITH A SFC TROUGH STATIONARY ACROSS THE NORTHERN HIGH PLAINS OF MT/WY. UPPER LEVEL DIVERGENCE IN THE EXIT REGION OF AN UPPER LEVEL JET COUPLED WITH DIURNAL INSTABILITY WILL SEE THE CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON WEST AND NORTH...THEN SPREADING SLOWLY SOUTHEAST TONIGHT. BEST CHANCE FOR STRONGER STORMS REMAINS ACROSS THE WESTERN THIRD OF THE STATE...MORE SO THE SOUTHWEST WHERE MODELS PORTRAY 800-1200 J/KG OF MUCAPE ALONG WITH 50KTS OF 0-6KM SHEAR. LATEST HRRR ALONG WITH THE 00Z 4KM NSSL WRF INDICATE CONVECTIVE DEVELOPMENT EARLY TO MID AFTERNOON FROM EASTERN MONTANA INTO SOUTHWEST AND WEST CENTRAL NORTH DAKOTA. WILL MAINTAIN HIGH CHANCE SCATTERED POPS FOR THIS AREA. FOR WEDNESDAY...FLOW ALOFT AND UPPER DIVERGENCE REMAINS UNCHANGED OVER THE NORTHERN PLAINS. SFC TROUGH ADVANCES EAST WED MORNING AND AFTERNOON INTO THE CENTRAL DAKOTAS. DAYTIME INSTABILITY AND BULK SHEAR INDICATE CHANCE FOR THUNDERSTORMS AREA WIDE...MARGINALLY SEVERE OVER THE ENTIRE COUNTY WARNING AREA (ALL OF WEST AND CENTRAL ND). WILL MAINTAIN POSSIBLE SEVERE WORDING IN THE HWO. DUE TO THE UNCERTAINTY...OPTED TO NOT INCLUDE IN THE GRIDS AT THIS TIME. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 129 PM CDT TUE JUN 23 2015 CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PERSIST INTO WEDNESDAY NIGHT...AS AN UPPER LEVEL SHORTWAVE TROUGH CONTINUES ON AN EASTWARD TRACK OUT OF THE STATE. A TRANSITION FROM QUASI ZONAL FLOW ALOFT INTO NORTHWEST FLOW IS EXPECTED THROUGH THURSDAY. THE CURRENT MODEL PACKAGE PROVIDES GOOD AGREEMENT ON NORTH/NORTHWEST FLOW ALOFT REMAINING IN PLACE THROUGH THE REST OF THE EXTENDED. SEVERAL EMBEDDED MID-LEVEL SHORTWAVES ARE PROJECTED ACROSS THE AREA...RESULTING IN FREQUENT CHANCES FOR ISOLATED/SCATTERED THUNDERSTORMS THOUGH PREDICTABILITY IS LOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 543 PM CDT TUE JUN 23 2015 ISOLD/SCT -TSRA POSSIBLE TODAY INTO TONIGHT OVER THE REGION. INITIAL DEVELOPMENT WEST AND NORTH CENTRAL THIS AFTERNOON...THEN EAST INTO THE SOUTH CENTRAL THIS EVENING. MAINLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD...WITH A DETERIORATION IN CONDITIONS WITH ANY THUNDERSTORM. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...AYD SHORT TERM...NH LONG TERM...AC AVIATION...AYD
AREA FORECAST DISCUSSION
NWS BISMARCK ND
129 PM CDT TUE JUN 23 2015 .SHORT TERM...(THIS AFTERNOON THROUGH WEDNESDAY) ISSUED AT 129 PM CDT TUE JUN 23 2015 FORECAST HIGHLIGHTS IN THE SHORT TERM PERIOD WILL BE CHANCES FOR THUNDERSTORMS THROUGH THE PERIOD...SOME MARGINALLY SEVERE SOUTHWEST THIS AFTERNOON/EVENING...AND ACROSS WESTERN AND CENTRAL NORTH DAKOTA WEDNESDAY. CURRENTLY...ACTIVE WEST-NORTHWEST FLOW ALOFT WITH A SFC TROUGH STATIONARY ACROSS THE NORTHERN HIGH PLAINS OF MT/WY. UPPER LEVEL DIVERGENCE IN THE EXIT REGION OF AN UPPER LEVEL JET COUPLED WITH DIURNAL INSTABILITY WILL SEE THE CHANCE FOR SHOWERS AND THUNDERSTORMS THIS AFTERNOON WEST AND NORTH...THEN SPREADING SLOWLY SOUTHEAST TONIGHT. BEST CHANCE FOR STRONGER STORMS REMAINS ACROSS THE WESTERN THIRD OF THE STATE...MORE SO THE SOUTHWEST WHERE MODELS PORTRAY 800-1200 J/KG OF MUCAPE ALONG WITH 50KTS OF 0-6KM SHEAR. LATEST HRRR ALONG WITH THE 00Z 4KM NSSL WRF INDICATE CONVECTIVE DEVELOPMENT EARLY TO MID AFTERNOON FROM EASTERN MONTANA INTO SOUTHWEST AND WEST CENTRAL NORTH DAKOTA. WILL MAINTAIN HIGH CHANCE SCATTERED POPS FOR THIS AREA. FOR WEDNESDAY...FLOW ALOFT AND UPPER DIVERGENCE REMAINS UNCHANGED OVER THE NORTHERN PLAINS. SFC TROUGH ADVANCES EAST WED MORNING AND AFTERNOON INTO THE CENTRAL DAKOTAS. DAYTIME INSTABILITY AND BULK SHEAR INDICATE CHANCE FOR THUNDERSTORMS AREA WIDE...MARGINALLY SEVERE OVER THE ENTIRE COUNTY WARNING AREA (ALL OF WEST AND CENTRAL ND). WILL MAINTAIN POSSIBLE SEVERE WORDING IN THE HWO. DUE TO THE UNCERTAINTY...OPTED TO NOT INCLUDE IN THE GRIDS AT THIS TIME. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 129 PM CDT TUE JUN 23 2015 CHANCES FOR SHOWERS AND THUNDERSTORMS ARE EXPECTED TO PERSIST INTO WEDNESDAY NIGHT...AS AN UPPER LEVEL SHORTWAVE TROUGH CONTINUES ON AN EASTWARD TRACK OUT OF THE STATE. A TRANSITION FROM QUASI ZONAL FLOW ALOFT INTO NORTHWEST FLOW IS EXPECTED THROUGH THURSDAY. THE CURRENT MODEL PACKAGE PROVIDES GOOD AGREEMENT ON NORTH/NORTHWEST FLOW ALOFT REMAINING IN PLACE THROUGH THE REST OF THE EXTENDED. SEVERAL EMBEDDED MID-LEVEL SHORTWAVES ARE PROJECTED ACROSS THE AREA...RESULTING IN FREQUENT CHANCES FOR ISOLATED/SCATTERED THUNDERSTORMS THOUGH PREDICTABILITY IS LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 129 PM CDT TUE JUN 23 2015 ISOLD/SCT -TSRA POSSIBLE TODAY INTO TONIGHT OVER THE REGION. INITIAL DEVELOPMENT WEST AND NORTH CENTRAL THIS AFTERNOON...THEN EAST INTO THE SOUTH CENTRAL THIS EVENING. MAINLY VFR CONDITIONS EXPECTED THROUGH THE FORECAST PERIOD...WITH A DETERIORATION IN CONDITIONS WITH ANY THUNDERSTORM. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...NH LONG TERM...AC AVIATION...NH
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
519 PM EDT TUE JUN 23 2015 .SYNOPSIS... THERE IS AN ENHANCED RISK FOR SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ACROSS SOUTH CENTRAL PENNSYLVANIA THROUGH THIS EVENING. FAIR AND DRY WEATHER IS EXPECTED TONIGHT INTO WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WITH COOLER TEMPERATURES EXPECTED. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... ...2117Z UPDATE... REMOVED ADDITIONAL COUNTIES FROM WW #342...ONLY FULTON/FRANKLIN/ADAMS/YORK AND LANCASTER COUNTIES REMAIN UNTIL 700 PM. DEEP CONVECTION EXITING SOUTHERN TIER COUNTIES THROUGH 22Z. AT THE SURFACE...A COLD FRONT CROSSING THE NORTH CENTRAL MOUNTAINS AT 21Z WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. THE PRIMARY SEVERE WX RISK HAS BEEN RELEGATED TO MY SOUTHERN TIER COUNTIES...WITH DAMAGING WINDS AND LARGE HAIL THE MAIN THREATS. SOME TRAINERS ARE PRODUCING LOCALLY FLOODING RAINFALL. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... THE LAST SEVERAL RUNS OF THE HRRR SHOWS SEMI-ORGANIZED/ORGANIZED TSTM CLUSTER EXITING THE SRN/SERN PORTIONS OF THE CWA BY 23Z WHICH WOULD COINCIDE WELL WITH THE EXPIRATION OF SVR TSTM WATCH #342. A NOTICEABLE CHANGE IN AIRMASS IS EXPECTED TONIGHT AS MUCH DRIER AIR WITH BELOW NORMAL PWS SPREADS OVER THE AREA BEHIND THE COLD FRONT. FCST MINS WILL RANGE FROM AROUND 50F IN THE NW TO THE LOW 60S IN THE SE. && .LONG TERM /WEDNESDAY THROUGH TUESDAY/... PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. DID NOT CHANGE MUCH ON WED. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. DID EDGE TEMPS DOWN A LITTLE...AND UP POPS SOME. DID NOT CHANGE MUCH FOR THE EXTENDED PERIOD. DID LOWER TEMPERATURES A LITTLE. OVERALL...AS WESTERN RIDGE BUILDS...LOOKING AT A SLIGHT COOL DOWN ACROSS THE EAST. THE MAIN THING IS THIS IS A WET PATTERN. ANYWAY...AFTER A BRIEF BREAK WITH THE SHOWERS ACROSS THE NORTH ON FRIDAY...THE WEEKEND LOOKS WET. PERHAPS A BRIEF BREAK FROM THE WET WEATHER BY NEXT TUE. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... SEVERE CONVECTION DROPPING SOUTH OF PA/MD BORDER BY 23Z. VFR CONDS RETURNING NORTH TO SOUTH THIS EVENING...WITH AREAS OF REDUCED VSBYS/CIGS IN EARLY MORNING VALLEY FOG WED MORNING AT KBFD AND KJST. WED LOOKS TO BE A NICE DAY WITH VFR CONDITIONS BY 12Z. MORE SHOWERS AND STORMS BY THU AFT. OUTLOOK... THU-SUN...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DEVOIR/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...MARTIN AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
453 PM EDT TUE JUN 23 2015 .SYNOPSIS... THERE IS AN ENHANCED RISK FOR SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ACROSS SOUTH CENTRAL PENNSYLVANIA THROUGH THIS EVENING. FAIR AND DRY WEATHER IS EXPECTED TONIGHT INTO WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WITH COOLER TEMPERATURES EXPECTED. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... ...2050Z UPDATE... REMOVED ADDITIONAL COUNTIES FROM WW #342...WATCH REMAINS IN EFFECT ALONG AND SOUTH OF A SOMERSET TO FRANKLIN TO CUMBERLAND DAUPHIN TO SCHUYLKILL COUNTY LINE. DEEP CONVECTION EXITING SOUTHERN TIER COUNTIES THROUGH 22Z. AT THE SURFACE...A COLD FRONT CROSSING THE NORTH CENTRAL MOUNTAINS AT 21Z WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. THE PRIMARY SEVERE WX RISK HAS BEEN RELEGATED TO MY SOUTHERN TIER COUNTIES...WITH DAMAGING WINDS AND LARGE HAIL THE MAIN THREATS. SOME TRAINERS ARE PRODUCING LOCALLY FLOODING RAINFALL. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... THE LAST SEVERAL RUNS OF THE HRRR SHOWS SEMI-ORGANIZED/ORGANIZED TSTM CLUSTER EXITING THE SRN/SERN PORTIONS OF THE CWA BY 23Z WHICH WOULD COINCIDE WELL WITH THE EXPIRATION OF SVR TSTM WATCH #342. A NOTICEABLE CHANGE IN AIRMASS IS EXPECTED TONIGHT AS MUCH DRIER AIR WITH BELOW NORMAL PWS SPREADS OVER THE AREA BEHIND THE COLD FRONT. FCST MINS WILL RANGE FROM AROUND 50F IN THE NW TO THE LOW 60S IN THE SE. && .LONG TERM /WEDNESDAY THROUGH TUESDAY/... PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. DID NOT CHANGE MUCH ON WED. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. DID EDGE TEMPS DOWN A LITTLE...AND UP POPS SOME. DID NOT CHANGE MUCH FOR THE EXTENDED PERIOD. DID LOWER TEMPERATURES A LITTLE. OVERALL...AS WESTERN RIDGE BUILDS...LOOKING AT A SLIGHT COOL DOWN ACROSS THE EAST. THE MAIN THING IS THIS IS A WET PATTERN. ANYWAY...AFTER A BRIEF BREAK WITH THE SHOWERS ACROSS THE NORTH ON FRIDAY...THE WEEKEND LOOKS WET. PERHAPS A BRIEF BREAK FROM THE WET WEATHER BY NEXT TUE. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... DID ADJUST TAFS FOR CONVECTION. STORMS SLOW TO MOVE SOUTH OF SOUTH CENTRAL PA. HOWEVER...EXPECT THINGS TO IMPROVE ACROSS THE SOUTH BY EARLY EVENING. THE MAIN THING WILL BE FOG LATE TONIGHT. ALSO SOME CHANCE OF LOW CIGS AT BFD AND JST. WED LOOKS TO BE A NICE DAY WITH VFR CONDITIONS BY 12Z. MORE SHOWERS AND STORMS BY THU AFT. OUTLOOK... THU-SUN...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DEVOIR/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...MARTIN AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
431 PM EDT TUE JUN 23 2015 .SYNOPSIS... THERE IS AN ENHANCED RISK FOR SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ACROSS SOUTH CENTRAL PENNSYLVANIA THROUGH THIS EVENING. FAIR AND DRY WEATHER IS EXPECTED TONIGHT INTO WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WITH COOLER TEMPERATURES EXPECTED. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... ...2030Z UPDATE... REMOVED NORTHERN THIRD OF WW #342...WATCH REMAINS IN EFFECT SOUTH OF A CLEARFIELD TO CENTRE TO SNYDER TO COLUMBIA COUNTY LINE. MESOANALYSIS AND LATEST HI RES MODEL DATA SUGGEST THE GREATEST RISK/THREAT FOR SEVERE T-STORMS WILL BE FOCUSED OVER SOUTH-CENTRAL PA /SOUTH OF I-80/ THIS AFTN THROUGH THIS EVENING. EXPECT COVERAGE AND INTENSITY OF STORMS TO INCREASE THRU 22-23Z ACROSS SOUTH- CENTRAL PA WHERE A VERY MOIST BLYR /SFC DEWPOINTS IN THE LOW 70S/ CONTINUES TO HEAT/DESTABILIZE FAIRLY AGGRESSIVELY. WE MAY CONSIDER TALKING WITH SPC ABOUT TRIMMING BACK THE FAR NRN COUNTIES INCLUDED IN SVR TSTM WATCH #342. A POTENT SHORT-WAVE TROUGH WILL PROGRESS FROM THE ONTARIO-QUEBEC BORDER TOWARD THE CANADIAN MARITIMES WITH A CORRIDOR OF WEAK HEIGHT FALLS OVERSPREADING THE NERN U.S. LATER TODAY INTO TONIGHT. AT THE SURFACE...THE COLD FRONT RELATED TO THE ERN CANADA TROUGH WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. AT 18Z THE COLD FRONT APPEARS TO BE PUSHING SEWD ACROSS THE LOWER GRT LKS. THE PRIMARY SEVERE WX RISK WILL BE DAMAGING WINDS GIVEN STRONG MAINLY WLY/UNIDIRECTIONAL FLOW THROUGH A DEEP LAYER...STEEP LLVL LAPSE RATES AND SUFFICIENT DCAPE OVER 1000 J/KG. AN ATTENDANT RISK FOR A FEW ROTATING STORMS CAPABLE OF PRODUCING AN ISOLATED TORNADO/LARGE HAIL WILL ALSO EXIST BUT AT A LOWER PROBABILITY. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... THE LAST SEVERAL RUNS OF THE HRRR SHOWS SEMI-ORGANIZED/ORGANIZED TSTM CLUSTER EXITING THE SRN/SERN PORTIONS OF THE CWA BY 23Z WHICH WOULD COINCIDE WELL WITH THE EXPIRATION OF SVR TSTM WATCH #342. A NOTICEABLE CHANGE IN AIRMASS IS EXPECTED TONIGHT AS MUCH DRIER AIR WITH BELOW NORMAL PWS SPREADS OVER THE AREA BEHIND THE COLD FRONT. FCST MINS WILL RANGE FROM AROUND 50F IN THE NW TO THE LOW 60S IN THE SE. && .LONG TERM /WEDNESDAY THROUGH TUESDAY/... PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. DID NOT CHANGE MUCH ON WED. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. DID EDGE TEMPS DOWN A LITTLE...AND UP POPS SOME. DID NOT CHANGE MUCH FOR THE EXTENDED PERIOD. DID LOWER TEMPERATURES A LITTLE. OVERALL...AS WESTERN RIDGE BUILDS...LOOKING AT A SLIGHT COOL DOWN ACROSS THE EAST. THE MAIN THING IS THIS IS A WET PATTERN. ANYWAY...AFTER A BRIEF BREAK WITH THE SHOWERS ACROSS THE NORTH ON FRIDAY...THE WEEKEND LOOKS WET. PERHAPS A BRIEF BREAK FROM THE WET WEATHER BY NEXT TUE. && .AVIATION /21Z TUESDAY THROUGH SUNDAY/... DID ADJUST TAFS FOR CONVECTION. STORMS SLOW TO MOVE SOUTH OF SOUTH CENTRAL PA. HOWEVER...EXPECT THINGS TO IMPROVE ACROSS THE SOUTH BY EARLY EVENING. THE MAIN THING WILL BE FOG LATE TONIGHT. ALSO SOME CHANCE OF LOW CIGS AT BFD AND JST. WED LOOKS TO BE A NICE DAY WITH VFR CONDITIONS BY 12Z. MORE SHOWERS AND STORMS BY THU AFT. OUTLOOK... THU-SUN...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...DEVOIR/STEINBUGL SHORT TERM...STEINBUGL LONG TERM...MARTIN AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
223 PM EDT TUE JUN 23 2015 .SYNOPSIS... THERE IS AN ENHANCED RISK FOR SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ACROSS SOUTH CENTRAL PENNSYLVANIA THROUGH THIS EVENING. FAIR AND DRY WEATHER IS EXPECTED TONIGHT INTO WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WITH COOLER TEMPERATURES EXPECTED. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... 18Z RADAR TRENDS...MESOANALYSIS AND LATEST HI RES MODEL DATA SUGGEST THE GREATEST RISK/THREAT FOR SEVERE T-STORMS WILL BE FOCUSED OVER SOUTH-CENTRAL PA /SOUTH OF I-80/ THIS AFTN THROUGH THIS EVENING. EXPECT COVERAGE AND INTENSITY OF STORMS TO INCREASE THRU 22-23Z ACROSS SOUTH-CENTRAL PA WHERE A VERY MOIST BLYR /SFC DEWPOINTS IN THE LOW 70S/ CONTINUES TO HEAT/DESTABILIZE FAIRLY AGGRESSIVELY. WE MAY CONSIDER TALKING WITH SPC ABOUT TRIMMING BACK THE FAR NRN COUNTIES INCLUDED IN SVR TSTM WATCH #342. A POTENT SHORT-WAVE TROUGH WILL PROGRESS FROM THE ONTARIO-QUEBEC BORDER TOWARD THE CANADIAN MARITIMES WITH A CORRIDOR OF WEAK HEIGHT FALLS OVERSPREADING THE NERN U.S. LATER TODAY INTO TONIGHT. AT THE SURFACE...THE COLD FRONT RELATED TO THE ERN CANADA TROUGH WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. AT 18Z THE COLD FRONT APPEARS TO BE PUSHING SEWD ACROSS THE LOWER GRT LKS. THE PRIMARY SEVERE WX RISK WILL BE DAMAGING WINDS GIVEN STRONG MAINLY WLY/UNIDIRECTIONAL FLOW THROUGH A DEEP LAYER...STEEP LLVL LAPSE RATES AND SUFFICIENT DCAPE OVER 1000 J/KG. AN ATTENDANT RISK FOR A FEW ROTATING STORMS CAPABLE OF PRODUCING AN ISOLATED TORNADO/LARGE HAIL WILL ALSO EXIST BUT AT A LOWER PROBABILITY. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... THE LAST SEVERAL RUNS OF THE HRRR SHOWS SEMI-ORGANIZED/ORGANIZED TSTM CLUSTER EXITING THE SRN/SERN PORTIONS OF THE CWA BY 23Z WHICH WOULD COINCIDE WELL WITH THE EXPIRATION OF SVR TSTM WATCH #342. A NOTICEABLE CHANGE IN AIRMASS IS EXPECTED TONIGHT AS MUCH DRIER AIR WITH BELOW NORMAL PWS SPREADS OVER THE AREA BEHIND THE COLD FRONT. FCST MINS WILL RANGE FROM AROUND 50F IN THE NW TO THE LOW 60S IN THE SE. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. DID NOT CHANGE MUCH ON WED. THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. DID EDGE TEMPS DOWN A LITTLE...AND UP POPS SOME. DID NOT CHANGE MUCH FOR THE EXTENDED PERIOD. DID LOWER TEMPERATURES A LITTLE. OVERALL...AS WESTERN RIDGE BUILDS...LOOKING AT A SLIGHT COOL DOWN ACROSS THE EAST. THE MAIN THING IS THIS IS A WET PATTERN. ANYWAY...AFTER A BRIEF BREAK WITH THE SHOWERS ACROSS THE NORTH ON FRIDAY...THE WEEKEND LOOKS WET. PERHAPS A BRIEF BREAK FROM THE WET WEATHER BY NEXT TUE. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... DID ADJUST TAFS FOR CONVECTION. STORMS SLOW TO MOVE SOUTH OF SOUTH CENTRAL PA. HOWEVER...EXPECT THINGS TO IMPROVE ACROSS THE SOUTH BY EARLY EVENING. THE MAIN THING WILL BE FOG LATE TONIGHT. ALSO SOME CHANCE OF LOW CIGS AT BFD AND JST. WED LOOKS TO BE A NICE DAY WITH VFR CONDITIONS BY 12Z. MORE SHOWERS AND STORMS BY THU AFT. OUTLOOK... THU-SUN...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...STEINBUGL NEAR TERM...STEINBUGL SHORT TERM...STEINBUGL LONG TERM...MARTIN AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
201 PM EDT TUE JUN 23 2015 .SYNOPSIS... SCATTERED TO NUMEROUS SEVERE THUNDERSTORMS ARE POSSIBLE ACROSS CENTRAL PENNSYLVANIA THROUGH THE EARLY EVENING HOURS. FAIR AND DRY WEATHER IS EXPECTED ON WEDNESDAY. AN UNSETTLED AND POTENTIALLY WET PATTERN WILL PERSIST FROM LATE WEEK INTO THE WEEKEND WITH COOLER TEMPERATURES. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... 15Z...COORDINATED WITH SPC ON NEW SEVERE TSTM WATCH #342. THIS WATCH COVERS THE SOUTH-CENTRAL 2/3RDS OF THE CWA AND IS IN EFFECT UNTIL 7PM EDT/23Z. A POTENT SHORT-WAVE TROUGH WILL PROGRESS FROM THE ONTARIO-QUEBEC BORDER TOWARD THE CANADIAN MARITIMES WITH A CORRIDOR OF WEAK HEIGHT FALLS OVERSPREADING THE NERN U.S. LATER TODAY INTO TONIGHT. AT THE SURFACE...THE COLD FRONT RELATED TO THE ERN CANADA TROUGH WILL ADVANCE SEWD THROUGH CENTRAL PA BY LATE THIS EVENING. CONSIDERABLE EARLY MORNING CLOUDS/PCPN SUGGEST SOME DEGREE OF LOWER CONFIDENCE IN AIRMASS RECOVERY/INSTABILITY THAT WILL OCCUR AHEAD OF THE COLD FRONT THIS AFTERNOON. THAT SAID...RADAR TRENDS CONTINUE TO INDICATE INCREASING STORM INTENSITIES UPSTREAM OVER WRN PA/PBZ CWA. GENERAL THINKING AMONG THE LOCAL OFFICE AND SPC IS THAT STORMS SHOULD EVOLVE/DEVELOP ESE FROM THE I-80 CORRIDOR. THE LATEST HRRR LARGELY AGREES WITH STORMS EXITING FAR SRN/SERN PA AROUND 23Z. THE COVERAGE AND INTENSITY OF THE STORMS WILL BE PREDICATED ON THE AMOUNT OF DESTABILIZATION THAT CAN OCCUR. THE PRIMARY SEVERE WX RISK WILL BE DAMAGING WINDS WITH ATTENDANT RISK FOR A FEW ROTATING STORMS CAPABLE OF PRODUCING AN ISOLATED TORNADO AS WELL AS LARGE HAIL. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... COULD BE LINGERING ACTIVITY ALONG MASON/DIXON LINE EARLY THIS EVE...BUT COLD FRONT PROGRESSING SOUTHWARD WILL END CONVECTION BY SUNSET. COOLER AND NOTICEABLY DRIER AIR PUSHES IN BEHIND THE FRONT...WITH NORTHERN SECTIONS SLIPPING INTO THE LOWER/MID 50S TONIGHT - A GOOD 15-20F COOLER THAN THIS MORNING. DRIER AIR TAKES A BIT LONGER TO WORK INTO THE SOUTH...WITH LOWS HANGING IN THE 60S. PLEASANT DAY ON WED WITH PLENTY OF SUNSHINE AND HIGH TEMPS NEARLY SPOT ON DAILY NORMALS. DID NOT CHANGE MUCH ON WED. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... THE AIR CONDITIONERS GET A BREAK WED NIGHT AS LOWS FALL BACK INTO THE 50S IN ALL BUT THE SOUTH CENTRAL MTNS AND LOWER SUSQ. CLOUDS INCREASE ON THU AS A MID LEVEL SHORTWAVE BRINGS POTENTIAL FOR SCT SHOWERS/TSTMS...ESP FOR SW HALF. TEMPS REMAIN CLOSE TO NORMAL. DID EDGE TEMPS DOWN A LITTLE...AND UP POPS SOME. DID NOT CHANGE MUCH FOR THE EXTENDED PERIOD. DID LOWER TEMPERATURES A LITTLE. OVERALL...AS WESTERN RIDGE BUILDS...LOOKING AT A SLIGHT COOL DOWN ACROSS THE EAST. THE MAIN THING IS THIS IS A WET PATTERN. ANYWAY...AFTER A BRIEF BREAK WITH THE SHOWERS ACROSS THE NORTH ON FRIDAY...THE WEEKEND LOOKS WET. PERHAPS A BRIEF BREAK FROM THE WET WEATHER BY NEXT TUE. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... DID ADJUST TAFS FOR CONVECTION. STORMS SLOW TO MOVE SOUTH OF SOUTH CENTRAL PA. HOWEVER...EXPECT THINGS TO IMPROVE ACROSS THE SOUTH BY EARLY EVENING. THE MAIN THING WILL BE FOG LATE TONIGHT. ALSO SOME CHANCE OF LOW CIGS AT BFD AND JST. WED LOOKS TO BE A NICE DAY WITH VFR CONDITIONS BY 12Z. MORE SHOWERS AND STORMS BY THU AFT. OUTLOOK... THU-SUN...REDUCTIONS IN SCT SHRA/TSRA. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...MARTIN/RXR NEAR TERM...STEINBUGL SHORT TERM...MARTIN LONG TERM...MARTIN AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
333 PM CDT TUE JUN 23 2015 .DISCUSSION... CURRENTLY...STRONG UPPER RIDGE EXTENDS FROM THE SOUTHERN PLAINS INTO THE MIDSOUTH. MEANWHILE A WEAK COLD FRONT HAS PUSHED INTO SOUTHERN MISSOURI AND WESTERN KY...JUST NORTH OF THE MIDSOUTH. VERY WARM AIR HAS PUSHED INTO THE MIDSOUTH WITH TEMPS IN THE MID 90S ACROSS MUCH OF THE AREA. SURFACE DEWPOINTS ARE POOLING ACROSS THE REGION...SOUTH OF THE COLD FRONT...WITH READINGS IN THE MID TO SOMETIMES UPPER 70S. THIS IS CREATING HEAT INDEX VALUES ABOVE 105 ACROSS MUCH OF THE MIDSOUTH. HAVE EXPANDED THE HEAT ADVISORY TO COVER MOST OF THE MIDSOUTH THIS AFTERNOON INTO WEDNESDAY. THE HRRR HAS BEEN TRYING TO DEVELOP CONVECTION ALONG THE WEAK COLD FRONT TO THE NORTH FOR THE LAST FEW HOURS BUT IT HAS NOT HAPPENED YET. GIVEN THE WEAK CAP AND SBCAPES AROUND 5000 J/KG THERE IS STILL THE POSSIBILITY OF ISOLATED STORMS DEVELOPING OVER THE NEXT FEW HOURS. TONIGHT...ANY CONVECTION WILL DISSIPATE BY 02Z OR SO WITH MOSTLY CLEAR SKIES AND WARM TEMPERATURES OVERNIGHT. LOWS IN THE 70S. WEDNESDAY...ANOTHER VERY HOT AND HUMID DAY WITH THE UPPER RIDGE CENTERED OVER THE AREA. EXPECT HIGHS IN THE MID 90S AND DEWPOINTS IN THE MID 70S. THE HEAT ADVISORY HAS BEEN EXTENDED THROUGH 7 PM THURSDAY FOR MOST OF THE MIDSOUTH FOR HEAT INDICES EXCEEDING 105 DEGREES WEDNESDAY AFTERNOON. AN ISOLATED AFTERNOON STORM COULD OCCUR ANYWHERE BUT THE BEST CHANCE WILL PROBABLY BE ACROSS NORTH MISSISSIPPI. THURSDAY...THE UPPER RIDGE WEAKENS A BIT ON THURSDAY BUT STILL HOT AND HUMID. HEAT ADVISORIES MAY NEED TO BE EXTENDED. STILL VERY WARM AIRMASS ACROSS THE REGION WITH 925MB TEMPS OF 28C ACROSS MUCH OF THE AREA. MODELS ARE POINTING TOWARD INCREASING MOISTURE MOVING UP FROM THE GULF WITH BETTER CHANCES OF AFTERNOON SHOWERS AND THUNDERSTORMS ACROSS NORTH MISSISSIPPI. FRIDAY AND SATURDAY...MAJOR PATTERN SHIFT AS THE UPPER RIDGE BREAKS DOWN AND A DEEP UPPER TROF DEVELOPS OVER THE EASTERN U.S. A COLD FRONT WILL PUSH THROUGH THE AREA FRIDAY INTO SATURDAY MORNING WITH NUMEROUS SHOWERS AND THUNDERSTORMS. A FEW STRONG TO SEVERE STORMS ARE POSSIBLE DURING THIS PERIOD. MUCH COOLER AND DRIER WEATHER WILL SETTLE OVER THE REGION LATER SATURDAY INTO EARLY NEXT WEEK AS THE REGION REMAINS UNDER THE INFLUENCE OF THE UNSEASONABLE DEEP UPPER TROF. SJM && .AVIATION... 18Z TAF CYCLE VFR CONDITIONS WILL PERSIST FOR MUCH OF THE FORECAST PERIOD. SOME ISOLATED THUNDERSTORMS WILL BE POSSIBLE THIS AFTERNOON AND EARLY THIS EVENING OVER NORTHERN SECTIONS OF THE FORECAST AREA. WINDS WILL BE MAINLY FROM THE WEST AT AROUND 10 KNOTS THIS AFTERNOON BEFORE BECOMING LIGHT AND VARIABLE TONIGHT. ARS && .MEG WATCHES/WARNINGS/ADVISORIES... AR...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CLAY-CRAIGHEAD- CRITTENDEN-CROSS-GREENE-LAWRENCE-LEE AR-MISSISSIPPI- PHILLIPS-POINSETT-RANDOLPH-ST. FRANCIS. MO...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR DUNKLIN-PEMISCOT. MS...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR ALCORN-BENTON MS- CALHOUN-CHICKASAW-COAHOMA-DESOTO-ITAWAMBA-LAFAYETTE-LEE MS- MARSHALL-MONROE-PANOLA-PONTOTOC-PRENTISS-QUITMAN- TALLAHATCHIE-TATE-TIPPAH-TISHOMINGO-TUNICA-UNION-YALOBUSHA. TN...HEAT ADVISORY UNTIL 7 PM CDT WEDNESDAY FOR CHESTER-CROCKETT-DYER- FAYETTE-HARDEMAN-HARDIN-HAYWOOD-LAKE-LAUDERDALE-MADISON- MCNAIRY-OBION-SHELBY-TIPTON. && $$
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
556 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL MOVE INTO AND THROUGH THE AREA TONIGHT...ACCOMPANIED BY SHOWERS AND STORMS ALONG AND IN ADVANCE OF THE SYSTEM. DRIER HIGH PRESSURE WILL BUILD INTO THE AREA ON WEDNESDAY...WITH ONLY ISOLATED SHOWERS OR STORMS EXPECTED LATE IN THE DAY ACROSS THE SOUTHERN THIRD OF THE REGION. SHOWERS AND STORMS INCREASE IN NUMBER AGAIN ON THURSDAY...AND CONTINUE INTO THE WEEKEND WITH A TREND TOWARD COOLER TEMPERATURES BY THE WEEKEND. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 540 PM EDT TUESDAY... CONVECTION GETTING ORGANIZED ACROSS NRN VA/MD...SW TO SRN WV. NOT SEEING ANYTHING SVR YET NEAR OUR AREA BUT STRONG. 21Z MESOANALYSIS STILL DEPICTING MLCAPES 2000-2500 J/KG ACROSS OUR CWA WITH BACKING WINDS ACROSS THE NEW RIVER VALLEY. CURRENT WATCH STILL LOOKS GOOD. THE LATEST HRRR AND RAP...SHOWING CONVECTION MOVING SE INTO THE NEW RIVER VALLEY TO LYH AREA BY 8 PM. MADE ADJUSTMENTS TO LOWER POPS ACROSS THE SE GIVEN LACK OF SUPPER CURRENTLY THERE AND INCREASED POPS TO LIKELY/CATEGORICAL IN THE NORTH AND NW TO ACCOUNT FOR BROKEN LINE OF CONVECTION. MINOR CHANGES TO SKY COVER AS WELL TO ACCOUNT FOR LESS CLOUD COVER EARLY ON IN THE SOUTHEAST. PREVIOUS VALID DISCUSSION... A COLD FRONT EXTENDED FROM WEST CENTRAL PA SOUTHWEST INTO SOUTHERN INDIANA. SOME ACTIVE CONVECTION WAS ALONG THIS FRONT FROM CENTRAL OH INTO CENTRAL PA. BY 02Z/10PM...GUIDANCE IS NOT QUITE AS UNIFORM AS TO THE POSITIONING OF THE PRECIPITATION. THE HRRR GIVES MORE CREDENCE TO WESTERLY FLOW LIMITING THE AMOUNT OF COVERAGE OVER SOUTHSIDE VIRGINIA AND NEIGHBORING PARTS OF NORTH CENTRAL NORTH CAROLINA...KEEPING ANY LINGERING PRECIPITATION ACROSS THE MOUNTAIN EMPIRE REGION OF SOUTHWEST VIRGINIA AND THE NORTHERN MOUNTAINS AND FOOTHILLS OF NC. THE RNK WRF ON THE OTHER HAND OFFERS A SOLUTION OF GENEROUS COVERAGE NOT ONLY THE AFOREMENTIONED WESTERN AREAS...BUT SOUTHSIDE VIRGINIA AND NORTH CENTRAL NORTH CAROLINA AS WELL. OUR FORECAST WILL LEAN MORE TOWARDS THE RNK WRF...BUT NOT AS ROBUST OF COVERAGE AS THE RNK WRF IN THE SOUTHEAST PART OF THE REGION. BY MIDNIGHT...ALL MODELS ARE GOOD AGREEMENT THAT LITTLE IF ANY PRECIPITATION WILL REMAIN ACROSS THE AREA. IF IT DOES...IT WOULD MOST LIKELY BE IN THE SOUTHEAST PART OF THE AREA...CLOSEST TO THE COLD FRONT. THE PUSH OF DRIER AIR INTO THE REGION DOES NOT START UNTIL WEDNESDAY...SO WE EXPECT LOW TEMPERATURES TONIGHT COMPARABLE TO THOSE OF LAST NIGHT. THE DAY ONE SEVERE OUTLOOK FROM THE STORM PREDICTION CENTER STILL OFFERS A SLIGHT RISK OF SEVERE WEATHER ACROSS THE AREA WITH THE PASSING OF THE MAIN AREA OF PRECIPITATION...WITH DAMAGING WINDS AND LARGE HAIL BEING THE MAIN CONCERNS. ISOLATED TORNADOES CANNOT BE RULE OUT. ON WEDNESDAY...THE COLD FRONT IS EXPECTED TO BE SOUTH OF THE AREA WITH DRIER HIGH PRESSURE AND SLIGHT COOLER AIR WORKING ITS WAY INTO THE REGION. HIGHS ARE EXPECTED TO RANGE FROM THE LOW TO MID 80S ACROSS THE MOUNTAINS AND AROUND 90 TO THE LOWER 90S ACROSS THE PIEDMONT. PRECIPITATION CHANCE WILL BE LIMITED TO MAINLY ISOLATED COVERAGE LATE IN THE DAY NEAR THE VA/NC BORDER AND POINTS SOUTH. THIS AREA WILL BE CLOSEST TO THE DEPARTED COLD FRONT...AND ITS PROXIMITY AND DAYTIME HEATING WILL ALLOW FOR A FEW SHOWERS AND STORMS. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM EDT TUESDAY... UPPER PATTERN KEEPS TRACK OF SHORT WAVES FROM THE UPPER MISSISSIPPI VALLEY INTO THE GREAT LAKES AND OHIO VALLEY THROUGH THURSDAY...THEN PATTERN BECOMES MUCH MORE AMPLIFIED THURSDAY NIGHT AND FRIDAY WITH A DEEP TROF OVER THE CENTRAL AND EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. MODELS SHOWED GOOD AGREEMENT THAT BULK OF DEEP MOISTURE AND LIFT WILL BE SOUTH OF THE FORECAST AREA ON WEDNESDAY NIGHT. THEN THE NEXT VORTICITY MAXIMUM...AREA OF LIFT...AND DEEP MOISTURE RETURNS TO THE AREA AGAIN ON THURSDAY AFTERNOON. THE HIGHEST PROBABILITY OF PRECIPITATION WILL BE IN THE NORTH AND NORTHWEST COUNTY WARNING AREA. GFS IS REASONABLE WITH SURFACE FEATURES WEDNESDAY NIGHT THROUGH FRIDAY. SLIGHTLY LOWER DEW POINTS ON WEDNESDAY NIGHT WILL RESULT IN COOLER MINIMUM TEMPERATURES. ON THURSDAY NIGHT LOW PRESSURE OVER THE MIDWEST WILL TRACK EAST AND OFF THE MID ATLANTIC COAST BY FRIDAY MORNING...LEAVING A WAVY STATIONARY BOUNDARY ACROSS THE REGION. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 130 PM EDT TUESDAY... MODELS CONTINUE TO SUGGEST AN UPPER LOW MAY CUT OFF OVER THE GREAT LAKES OR OHIO VALLEY AS A SERIES OF SHORT WAVES TRACK DOWN THE WEST SIDE OF THE UPPER TROF. THE PATTERN WILL REMAIN AMPLIFIED THROUGH TUESDAY. SO EXPECTING LOWER 500 MB HEIGHTS AND COOLER 850 MB TEMPERATURES THROUGH THE PERIOD. THE TROUGH DIGS ENOUGH THAT RIGHT REAR QUADRANT OF THE JET STREAKS ASSOCIATED WITH EACH SHORT WAVE WILL ENHANCE THE LIFT OVER THE FORECAST AREA ON FRIDAY NIGHT INTO SATURDAY NIGHT. LIFT WILL ALSO BE AIDED BY 25 TO 30 KNOT EAST 850 MB WINDS AS A SURFACE LOW TRACKS ACROSS THE TENNESSEE VALLEY AND MID ATLANTIC REGION THIS WEEKEND. NCEP FAVORED THE GENERAL TIMING AND POSITION OF THE ECMWF WHICH HAS ANOTHER FRONTAL SYSTEM AND WAVE OF LOW PRESSURE OVER THE TENNESSEE VALLEY ON TUESDAY. WIDESPREAD CLOUDS AND PRECIPITATION ON SATURDAY AND SUNDAY WILL RESULT IN BELOW NORMAL TEMPERATURES. HAVE LOWERED MAXIMUM TEMPERATURES FOR BOTH DAYS. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... AS OF 140 PM EDT TUESDAY... A COLD FRONT WAS APPROACHING THE AREA FROM KY/OH/PA. CONVECTION IS EXPECTED TO FIRE THIS AFTERNOON ALONG AND IN ADVANCE OF THIS FRONT AND PROGRESS INTO THE FORECAST AREA. COVERAGE WILL INCREASE AS THE FRONT DRAWS CLOSER AND EVENTUALLY ENTERS THE REGION THIS EVENING. VERY GUSTY WINDS AND HAIL MAY ACCOMPANY THE STRONGER STORMS. VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE REGION. LOCALIZED AND BRIEF MVFR/IFR CONDITIONS ARE EXPECTED WITH THE HEAVIER CORES. OVERNIGHT...THE FRONT WILL PASS SOUTH OF THE AREA WITH LINGERING ISOLATED TO SCATTERED SHOWERS FOLLOWING THE MAIN LINE OF STORMS. FOG FORMATION IS EXPECTED TO TAKE PLACE IN THE SHELTERED VALLEYS...ESPECIALLY THOSE THAT RECEIVE RAIN FROM THE UPCOMING EVENT. SOME AREAS OF MVFR CIGS ARE EXPECTED ACROSS THE MOUNTAINS AS LINGERING LOW LEVEL MOISTURE AND PREVAILING NW 850 MB WINDS ALLOW FOR AN UPSLOPE COMPONENT COINCIDENT TO THE MOISTURE. WEDNESDAY MORNING...ANY SUB-VFR CONDITIONS WILL IMPROVE TO VFR AS HIGH PRESSURE BUILDS INTO THE REGION. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL HELP KEEP THE AREA VFR WEDNESDAY AFTERNOON. ADDITIONAL SHOWERS OR STORMS WILL BE LIMITED TO ISOLATED COVERAGE ACROSS THE NORTH...CLOSEST TO THE EXITING COLD FRONT. THE FRONT WILL RETURN NORTH ACROSS THE AREA ON THURSDAY AS OUR NEXT SHORTWAVE TROUGH APPROACHES FROM THE NORTHWEST. LOOK FOR A RETURN OF ISOLATED TO SCATTERED COVERAGE FOR THE AREA. THURSDAY NIGHT INTO FRIDAY...THE SHORTWAVE CROSSES THROUGH THE MID-ATLANTIC STATES BRINGING AN ASSOCIATED COLD FRONT WITH IT. PRECIPITATION CHANCES WILL INCREASE EVEN MORE...WITH A BETTER CHANCE OF MORE EXPANSIVE SUB-VFR CONDITIONS. THROUGH THE WEEKEND...AN UPPER TROUGH STALLS AND DEEPENS OVER THE MIDWEST WITH A PERSISTENT BAROCLINIC ZONE ACROSS OUR REGION. LOOK FOR COOLER CONDITIONS...BETTER CHANCES OF SUB-VFR CONDITIONS AND ADDITIONAL SHOWERS AND STORMS. && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS/WP SHORT TERM...AMS LONG TERM...AMS AVIATION...DS EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
348 PM EDT TUE JUN 23 2015 .SYNOPSIS... A COLD FRONT WILL MOVE INTO AND THROUGH THE AREA TONIGHT...ACCOMPANIED BY SHOWERS AND STORMS ALONG AND IN ADVANCE OF THE SYSTEM. DRIER HIGH PRESSURE WILL BUILD INTO THE AREA ON WEDNESDAY...WITH ONLY ISOLATED SHOWERS OR STORMS EXPECTED LATE IN THE DAY ACROSS THE SOUTHERN THIRD OF THE REGION. SHOWERS AND STORMS INCREASE IN NUMBER AGAIN ON THURSDAY...AND CONTINUE INTO THE WEEKEND WITH A TREND TOWARD COOLER TEMPERATURES BY THE WEEKEND. && .NEAR TERM /THROUGH WEDNESDAY/... AS OF 230 PM EDT TUESDAY... ISOLATED SHOWERS HAVE BEGUN FORMING WITHIN THE LEE SIDE TROUGH EAST OF THE CREST OF THE BLUE RIDGE. WHILE SOME OF THESE SHOWERS MAY DEVELOP INTO STORMS AND MAKE PROGRESS EASTWARD...THE REAL WEATHER STORY IS LOOMING TO OUR NORTHWEST. A COLD FRONT EXTENDED FROM WEST CENTRAL PA SOUTHWEST INTO SOUTHERN INDIANA. SOME ACTIVE CONVECTION WAS ALONG THIS FRONT FROM CENTRAL OH INTO CENTRAL PA. OTHER SHOWER AND THUNDERSTORM ACTIVITY WAS IN ADVANCE OF THIS FRONT...CURRENTLY AS CLOSE AS ISOLATED BETWEEN CHARLESTON WV AND HANCOCK MD. THIS ORIENTATION OF PRECIPITATION WAS MATCHING FAIRLY WELL WITH GUIDANCE OFFERED BY THE 17Z/1PM RUN OF THE HRRR...WITH THE 12Z/8AM RUN OF THE RNK WRF NOT TOO UNLIKE IT AS WELL. THE BIGGEST DIFFERENCES WERE THE POSITIONING AND COVERAGE OF THE LEE SIDE CONVECTION ACROSS THE EASTERN PART OF THE AREA. THE WRF IS TOO FAR WEST AND THE HRRR IS TOO NUMEROUS. MESOSCALE MODELS SUGGEST THE LEADING PRECIPITATION IN ADVANCE OF THE FRONT TO INCREASE IN COVERAGE OVER THE NEXT FEW HOURS AND ARRIVE IN OUR I-64 CORRIDOR AROUND 21Z/5PM. THE PRECIPITATION IS EXPECTED TO CONTINUE TO EXPAND IN COVERAGE AND PROGRESS SOUTHEAST INTO AND THROUGH OUR REGION....REACHING A WYTHEVILLE TO ROANOKE TO LYNCHBURG TO BUCKINGHAM LINE AROUND 23Z/7PM. BY 02Z/10PM...GUIDANCE IS NOT QUITE AS UNIFORM AS TO THE POSITIONING OF THE PRECIPITATION. THE HRRR GIVES MORE CREDENCE TO WESTERLY FLOW LIMITING THE AMOUNT OF COVERAGE OVER SOUTHSIDE VIRGINIA AND NEIGHBORING PARTS OF NORTH CENTRAL NORTH CAROLINA...KEEPING ANY LINGERING PRECIPITATION ACROSS THE MOUNTAIN EMPIRE REGION OF SOUTHWEST VIRGINIA AND THE NORTHERN MOUNTAINS AND FOOTHILLS OF NC. THE RNK WRF ON THE OTHER HAND OFFERS A SOLUTION OF GENEROUS COVERAGE NOT ONLY THE AFOREMENTIONED WESTERN AREAS...BUT SOUTHSIDE VIRGINIA AND NORTH CENTRAL NORTH CAROLINA AS WELL. OUR FORECAST WILL LEAN MORE TOWARDS THE RNK WRF...BUT NOT AS ROBUST OF COVERAGE AS THE RNK WRF IN THE SOUTHEAST PART OF THE REGION. BY MIDNIGHT...ALL MODELS ARE GOOD AGREEMENT THAT LITTLE IF ANY PRECIPITATION WILL REMAIN ACROSS THE AREA. IF IT DOES...IT WOULD MOST LIKELY BE IN THE SOUTHEAST PART OF THE AREA...CLOSEST TO THE COLD FRONT. THE PUSH OF DRIER AIR INTO THE REGION DOES NOT START UNTIL WEDNESDAY...SO WE EXPECT LOW TEMPERATURES TONIGHT COMPARABLE TO THOSE OF LAST NIGHT. THE DAY ONE SEVERE OUTLOOK FROM THE STORM PREDICTION CENTER STILL OFFERS A SLIGHT RISK OF SEVERE WEATHER ACROSS THE AREA WITH THE PASSING OF THE MAIN AREA OF PRECIPITATION...WITH DAMAGING WINDS AND LARGE HAIL BEING THE MAIN CONCERNS. ISOLATED TORNADOES CANNOT BE RULE OUT. THE LATEST MESOSCALE DISCUSSION OFFERS THE AREA FROM ROUGHLY ROANOKE NORTH TO COVINGTON AND POINTS EASTWARD AS THE REGION OF GREATEST POTENTIAL FOR THEIR ISSUANCE OF A SEVERE THUNDERSTORM WATCH. ON WEDNESDAY...THE COLD FRONT IS EXPECTED TO BE SOUTH OF THE AREA WITH DRIER HIGH PRESSURE AND SLIGHT COOLER AIR WORKING ITS WAY INTO THE REGION. HIGHS ARE EXPECTED TO RANGE FROM THE LOW TO MID 80S ACROSS THE MOUNTAINS AND AROUND 90 TO THE LOWER 90S ACROSS THE PIEDMONT. PRECIPITATION CHANCE WILL BE LIMITED TO MAINLY ISOLATED COVERAGE LATE IN THE DAY NEAR THE VA/NC BORDER AND POINTS SOUTH. THIS AREA WILL BE CLOSEST TO THE DEPARTED COLD FRONT...AND ITS PROXIMITY AND DAYTIME HEATING WILL ALLOW FOR A FEW SHOWERS AND STORMS. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... AS OF 300 PM EDT TUESDAY... UPPER PATTERN KEEPS TRACK OF SHORT WAVES FROM THE UPPER MISSISSIPPI VALLEY INTO THE GREAT LAKES AND OHIO VALLEY THROUGH THURSDAY...THEN PATTERN BECOMES MUCH MORE AMPLIFIED THURSDAY NIGHT AND FRIDAY WITH A DEEP TROF OVER THE CENTRAL AND EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. MODELS SHOWED GOOD AGREEMENT THAT BULK OF DEEP MOISTURE AND LIFT WILL BE SOUTH OF THE FORECAST AREA ON WEDNESDAY NIGHT. THEN THE NEXT VORTICITY MAXIMUM...AREA OF LIFT...AND DEEP MOISTURE RETURNS TO THE AREA AGAIN ON THURSDAY AFTERNOON. THE HIGHEST PROBABILITY OF PRECIPITATION WILL BE IN THE NORTH AND NORTHWEST COUNTY WARNING AREA. GFS IS REASONABLE WITH SURFACE FEATURES WEDNESDAY NIGHT THROUGH FRIDAY. SLIGHTLY LOWER DEW POINTS ON WEDNESDAY NIGHT WILL RESULT IN COOLER MINIMUM TEMPERATURES. ON THURSDAY NIGHT LOW PRESSURE OVER THE MIDWEST WILL TRACK EAST AND OFF THE MID ATLANTIC COAST BY FRIDAY MORNING...LEAVING A WAVY STATIONARY BOUNDARY ACROSS THE REGION. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... AS OF 130 PM EDT TUESDAY... MODELS CONTINUE TO SUGGEST AN UPPER LOW MAY CUT OFF OVER THE GREAT LAKES OR OHIO VALLEY AS A SERIES OF SHORT WAVES TRACK DOWN THE WEST SIDE OF THE UPPER TROF. THE PATTERN WILL REMAIN AMPLIFIED THROUGH TUESDAY. SO EXPECTING LOWER 500 MB HEIGHTS AND COOLER 850 MB TEMPERATURES THROUGH THE PERIOD. THE TROUGH DIGS ENOUGH THAT RIGHT REAR QUADRANT OF THE JET STREAKS ASSOCIATED WITH EACH SHORT WAVE WILL ENHANCE THE LIFT OVER THE FORECAST AREA ON FRIDAY NIGHT INTO SATURDAY NIGHT. LIFT WILL ALSO BE AIDED BY 25 TO 30 KNOT EAST 850 MB WINDS AS A SURFACE LOW TRACKS ACROSS THE TENNESSEE VALLEY AND MID ATLANTIC REGION THIS WEEKEND. NCEP FAVORED THE GENERAL TIMING AND POSITION OF THE ECMWF WHICH HAS ANOTHER FRONTAL SYSTEM AND WAVE OF LOW PRESSURE OVER THE TENNESSEE VALLEY ON TUESDAY. WIDESPREAD CLOUDS AND PRECIPITATION ON SATURDAY AND SUNDAY WILL RESULT IN BELOW NORMAL TEMPERATURES. HAVE LOWERED MAXIMUM TEMPERATURES FOR BOTH DAYS. && .AVIATION /20Z TUESDAY THROUGH SUNDAY/... AS OF 140 PM EDT TUESDAY... A COLD FRONT WAS APPROACHING THE AREA FROM KY/OH/PA. CONVECTION IS EXPECTED TO FIRE THIS AFTERNOON ALONG AND IN ADVANCE OF THIS FRONT AND PROGRESS INTO THE FORECAST AREA. COVERAGE WILL INCREASE AS THE FRONT DRAWS CLOSER AND EVENTUALLY ENTERS THE REGION THIS EVENING. VERY GUSTY WINDS AND HAIL MAY ACCOMPANY THE STRONGER STORMS. VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE REGION. LOCALIZED AND BRIEF MVFR/IFR CONDITIONS ARE EXPECTED WITH THE HEAVIER CORES. OVERNIGHT...THE FRONT WILL PASS SOUTH OF THE AREA WITH LINGERING ISOLATED TO SCATTERED SHOWERS FOLLOWING THE MAIN LINE OF STORMS. FOG FORMATION IS EXPECTED TO TAKE PLACE IN THE SHELTERED VALLEYS...ESPECIALLY THOSE THAT RECEIVE RAIN FROM THE UPCOMING EVENT. SOME AREAS OF MVFR CIGS ARE EXPECTED ACROSS THE MOUNTAINS AS LINGERING LOW LEVEL MOISTURE AND PREVAILING NW 850 MB WINDS ALLOW FOR AN UPSLOPE COMPONENT COINCIDENT TO THE MOISTURE. WEDNESDAY MORNING...ANY SUB-VFR CONDITIONS WILL IMPROVE TO VFR AS HIGH PRESSURE BUILDS INTO THE REGION. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL HELP KEEP THE AREA VFR WEDNESDAY AFTERNOON. ADDITIONAL SHOWERS OR STORMS WILL BE LIMITED TO ISOLATED COVERAGE ACROSS THE NORTH...CLOSEST TO THE EXITING COLD FRONT. THE FRONT WILL RETURN NORTH ACROSS THE AREA ON THURSDAY AS OUR NEXT SHORTWAVE TROUGH APPROACHES FROM THE NORTHWEST. LOOK FOR A RETURN OF ISOLATED TO SCATTERED COVERAGE FOR THE AREA. THURSDAY NIGHT INTO FRIDAY...THE SHORTWAVE CROSSES THROUGH THE MID-ATLANTIC STATES BRINGING AN ASSOCIATED COLD FRONT WITH IT. PRECIPITATION CHANCES WILL INCREASE EVEN MORE...WITH A BETTER CHANCE OF MORE EXPANSIVE SUB-VFR CONDITIONS. THROUGH THE WEEKEND...AN UPPER TROUGH STALLS AND DEEPENS OVER THE MIDWEST WITH A PERSISTENT BAROCLINIC ZONE ACROSS OUR REGION. LOOK FOR COOLER CONDITIONS...BETTER CHANCES OF SUB-VFR CONDITIONS AND ADDITIONAL SHOWERS AND STORMS. && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS NEAR TERM...DS SHORT TERM...AMS LONG TERM...AMS AVIATION...DS EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
149 PM EDT TUE JUN 23 2015 .SYNOPSIS... A WEAK COOL FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND PASS SOUTH THROUGH THE REGION OVERNIGHT INTO EARLY WEDNESDAY. DRIER HIGH PRESSURE FOLLOWS THE FRONT WEDNESDAY INTO THURSDAY BEFORE MOISTURE RETURNS BACK NORTH BY THE END OF THE WEEK. ANOTHER FRONTAL SYSTEM WILL DIP SOUTH INTO THE AREA OVER THE WEEKEND AND STALL...BRINGING BETTER CHANCES OF SHOWERS AND STORMS ALONG WITH COOLER TEMPERATURES SATURDAY INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1240 PM EDT TUESDAY... STILL PPINE ON LOCAL KFCX 88D. HOWEVER...THAT IS EXPECTED TO CHANGE VERY SHORTLY WITH THE ANTICIPATION OF SHOWER AND STORM DEVELOPMENT UPSTREAM IN KY/WV IN ADVANCE OF AN APPROACHING COLD FRONT. ACTIVITY IS EXPECTED TO HEAD SOUTHEAST WITH ISOLATED COVERAGE ENTERING THE NORTHWEST PART OF THE FORECAST AREA AROUND 200 PM. OTHER ISOLATED DEVELOPMENT WILL BE POSSIBLE ABOUT THE SAME TIME EAST OF THE CREST OF THE BLUE RIDGE WITHIN AN AXIS OF A LEE SIDE TROUGH. THE BETTER COVERAGE OF SHOWERS AND STORMS WILL ENTER THE NORTHWEST PART OF THE REGION MORE IN THE 5PM TO 6PM TIME FRAME. HAVE RAMPED UP PRECIPITATION CHANCES INTO THE LIKELY CATEGORY ACROSS THE NORTHERN HALF OF THE FORECAST AREA BETWEEN 6PM AND 9PM. AS WHAT IS EXPECTED TO BE A LINE OF CONVECTION WITH POTENTIALLY STRONG TO DAMAGING WINDS MOVES THROUGH THE AREA...A PREDOMINATELY WESTERLY FLOW WILL LIMIT COVERAGE IMMEDIATELY ALONG AND EAST OF THE CREST OF THE BLUE RIDGE. COVERAGE MAY INCREASE AGAIN ONCE ACTIVITY GETS EAST OF THE DANVILLE AREA. HIGH TEMPERATURES ARE STILL ON TRACK TO EARLIER FORECAST HIGHS...SO NO ADJUSTMENTS THERE. AS OF 945 AM EDT TUESDAY... THE LATEST FORECAST NEEDS NO MAJOR CHANGES AT THIS TIME. TIMING OF CONVECTION STILL LOOKS MOST PROBABLE STARTING AROUND THE MID- AFTERNOON AND ONWARD. HOT CONDITIONS STILL ARE LIKELY WITH NEAR RECORD HIGH TEMPERATURES FOR PARTS OF THE REGION. HAVE MADE MINOR TWEAKS TO THE HOURLY TEMPERATURE...DEW POINT...AND SKY COVER THROUGH THE EARLY AFTERNOON BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT TWO TO THREE HOURS. AS OF 150 AM EDT TUESDAY... AGAIN LOOKS TO BE THE HOTTEST DAY OF THE YEAR SO FAR THIS AFTERNOON WITH 85H TEMPS PUSHING +22-23C AIDED BY WESTERLY DOWNSLOPING AND COMPRESSION AHEAD OF THE FRONT APPROACHING FROM THE NORTH. THIS COMBINED WITH GOOD HEATING SHOULD PUSH SOME SPOTS TO NEAR 100 OUT EAST WITH EVEN A FEW LOW 90S MOUNTAINS. HOWEVER STILL APPEARS ENOUGH MIXING OUT OF DEWPOINTS LATER THIS AFTERNOON TO KEEP HEAT INDEX VALUES JUST BELOW CRITERIA. THUS WILL MENTION IN THE HWO BUT NOT HOIST ANY ADVISORY HEADLINES AT THIS POINT. OTHER BIGGER CONCERN WITH THE POTENTIAL STRONG TO SEVERE STORM THREAT AS CONVECTION LINES UP WITH THE PRE-FRONTAL TYPE OUTFLOW JUST AHEAD OF THE BOUNDARY HEADING IN FROM THE NW LATER ON. MODELS TENDING TO DEVELOP AT LEAST A BROKEN LINE JUST NW OF THE CWA BY MID AFTERNOON AND THEN SHIFT IT SE INTO HIGH INSTABILITY/DCAPES INCLUDING STEEP LAPSES AS THE FRONT JUMPS OUT TO THE LEE TROUGH. HOWEVER GUIDANCE DIFFERS ON HOW THIS BAND OF CONVECTION INTERACTS WITH THE DEEP...WELL MIXED WESTERLY FLOW REGIME WITH SOME SPLITTING ALONG THE BLUE RIDGE...AND OTHERS PROGRESSING ACROSS WHILE STRENGTHENING IN THE PIEDMONT AND OUT WEST. IF SLOWER... SIMILAR TO THE LATEST ENSEMBLES COULD SEE A LINE SWING THROUGH MUCH OF THE NORTH/NW CWA BY EARLY EVENING BEFORE SPLITTING IN TWO AS SUPPORTED BY THE HRRR WITH BEST COVERAGE NE WHERE FARTHER REMOVED FROM THE DOWNSLOPE...AND OVER THE FAR WEST PER CONVERGENCE. GIVEN SO MUCH WEST WIND AND NVA OVER THE REGION FOR MUCH OF THE DAY...TRENDED SLOWER WITH BRIEF LIKELY POPS FAR NW/NE...AND HIGHER CHANCES ELSW EAST OF THE BLUE RIDGE WHERE THE LOW LEVEL FLOW DOES BACK LATE. ALSO HIGHER CHANCES SE WEST VA SOUTH ALONG THE I-77 CORRIDOR WHERE OUTFLOW COULD SPARK SOME SHALLOW CONVECTION EARLY ON. OTRW APPEARS LOWEST POPS 20/30S NEW RIVER/ROANOKE VALLEYS PENDING TIMING AND DEGREE OF MIXING INTO EARLY EVENING. ALTHOUGH STRONGER WINDS ALOFT STAY TO THE NORTH...UNIDIRECTIONAL FLOW COULD ALLOW FOR MULTICELL CLUSTERS/BANDS MAKING FOR DECENT DAMAGING WIND POTENTIAL IN THIS ENVIRONMENT IF STORMS CAN ORGANIZE. ADDITIONAL STRONGER STORMS MAY LINGER OVER THE SOUTH/SE THIS EVENING AND PERHAPS PERSIST IN SPOTS OVER THE FAR WEST/SW OVERNIGHT AS THE FRONT SAGS SOUTH BUT STALLS OUT CROSSING THE WEST. HOWEVER THINKING LOSS OF HEATING SHOULD PRECLUDE MUCH COVERAGE AFTER MIDNIGHT ESPCLY IF A LINE SWINGS THROUGH OR SPLITS SO ONLY LEAVING IN ISOLATED COVERAGE SOUTHERN/SW SECTIONS LATE. OTRW SOME CLEARING LIKELY IN ALL EXCEPT THE FAR WEST/SW GIVEN WESTERLY UPSLOPE FLOW...WITH PATCHY FOG AROUND UNDER MUGGY LOWS IN THE 65-70 RANGE WEST AND 68-74 EAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 334 AM EDT TUESDAY... A COOL FRONT WILL SLIDE SOUTH AND STALL OVER THE CAROLINAS WEDNESDAY. MODELS ARE ALLOWING MORE DRY AIR THAN PREVIOUS RUNS TO ENTER THE AREA...ESPECIALLY ACROSS THE NORTH. DEW POINTS WEDNESDAY AFTERNOON COULD BE AS LOW AS THE MID 50S. NOT MUCH COOL AIR WITH THE FRONTAL PASSAGE AND WITH A HIGH SUMMER SUN AND DRY AIR...TEMPERATURES WILL WARM INTO THE 80S ACROSS THE MOUNTAINS TO THE LOWER TO MID 90S EAST. WITH THE PUNCH OF DRY AIR...THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE LOW AND ISOLATED AT BEST. A SURFACE REFLECTION ALONG THE STALL FRONT OVER THE CAROLINAS WILL EDGE NORTHWARD ON THURSDAY. THIS REFECTION WILL BRING AN INCREASE IN MOISTURE AND THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS. FOR NOW...MODELS ARE INDICATING ANY CONVECTION THURSDAY WILL BE DIURNAL...BUT WE WILL NEED TO KEEP AN EYE TO THE NORTHWEST FOR ANY COMPLEXES DEVELOPING OVER THE UPPER MIDWEST AND OHIO VALLEY. TEMPERATURES THURSDAY WILL ONCE AGAIN BE WARMER THAN NORMAL WITH MID TO UPPER 80S WEST TO LOWER TO MID 90S EAST. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 140 PM EDT TUESDAY... A COLD FRONT WAS APPROACHING THE AREA FROM KY/OH/PA. CONVECTION IS EXPECTED TO FIRE THIS AFTERNOON ALONG AND IN ADVANCE OF THIS FRONT AND PROGRESS INTO THE FORECAST AREA. COVERAGE WILL INCREASE AS THE FRONT DRAWS CLOSER AND EVENTUALLY ENTERS THE REGION THIS EVENING. VERY GUSTY WINDS AND HAIL MAY ACCOMPANY THE STRONGER STORMS. VFR CONDITIONS ARE EXPECTED FOR MUCH OF THE REGION. LOCALIZED AND BRIEF MVFR/IFR CONDITIONS ARE EXPECTED WITH THE HEAVIER CORES. OVERNIGHT...THE FRONT WILL PASS SOUTH OF THE AREA WITH LINGERING ISOLATED TO SCATTERED SHOWERS FOLLOWING THE MAIN LINE OF STORMS. FOG FORMATION IS EXPECTED TO TAKE PLACE IN THE SHELTERED VALLEYS...ESPECIALLY THOSE THAT RECEIVE RAIN FROM THE UPCOMING EVENT. SOME AREAS OF MVFR CIGS ARE EXPECTED ACROSS THE MOUNTAINS AS LINGERING LOW LEVEL MOISTURE AND PREVAILING NW 850 MB WINDS ALLOW FOR AN UPSLOPE COMPONENT COINCIDENT TO THE MOISTURE. WEDNESDAY MORNING...ANY SUB-VFR CONDITIONS WILL IMPROVE TO VFR AS HIGH PRESSURE BUILDS INTO THE REGION. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL HELP KEEP THE AREA VFR WEDNESDAY AFTERNOON. ADDITIONAL SHOWERS OR STORMS WILL BE LIMITED TO ISOLATED COVERAGE ACROSS THE NORTH...CLOSEST TO THE EXITING COLD FRONT. THE FRONT WILL RETURN NORTH ACROSS THE AREA ON THURSDAY AS OUR NEXT SHORTWAVE TROUGH APPROACHES FROM THE NORTHWEST. LOOK FOR A RETURN OF ISOLATED TO SCATTERED COVERAGE FOR THE AREA. THURSDAY NIGHT INTO FRIDAY...THE SHORTWAVE CROSSES THROUGH THE MID-ATLANTIC STATES BRINGING AN ASSOCIATED COLD FRONT WITH IT. PRECIPITATION CHANCES WILL INCREASE EVEN MORE...WITH A BETTER CHANCE OF MORE EXPANSIVE SUB-VFR CONDITIONS. THROUGH THE WEEKEND...AN UPPER TROUGH STALLS AND DEEPENS OVER THE MIDWEST WITH A PERSISTENT BAROCLINIC ZONE ACROSS OUR REGION. LOOK FOR COOLER CONDITIONS...BETTER CHANCES OF SUB-VFR CONDITIONS AND ADDITIONAL SHOWERS AND STORMS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE TODAY. BELOW ARE THE CURRENT RECORDS FOR THE DATE. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...DS/JH SHORT TERM...RCS LONG TERM...AMS AVIATION...DS CLIMATE...CF EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
100 PM EDT TUE JUN 23 2015 .SYNOPSIS... A WEAK COOL FRONT WILL APPROACH FROM THE NORTHWEST TODAY AND PASS SOUTH THROUGH THE REGION OVERNIGHT INTO EARLY WEDNESDAY. DRIER HIGH PRESSURE FOLLOWS THE FRONT WEDNESDAY INTO THURSDAY BEFORE MOISTURE RETURNS BACK NORTH BY THE END OF THE WEEK. ANOTHER FRONTAL SYSTEM WILL DIP SOUTH INTO THE AREA OVER THE WEEKEND AND STALL...BRINGING BETTER CHANCES OF SHOWERS AND STORMS ALONG WITH COOLER TEMPERATURES SATURDAY INTO SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1240 PM EDT TUESDAY... STILL PPINE ON LOCAL KFCX 88D. HOWEVER...THAT IS EXPECTED TO CHANGE VERY SHORTLY WITH THE ANTICIPATION OF SHOWER AND STORM DEVELOPMENT UPSTREAM IN KY/WV IN ADVANCE OF AN APPROACHING COLD FRONT. ACTIVITY IS EXPECTED TO HEAD SOUTHEAST WITH ISOLATED COVERAGE ENTERING THE NORTHWEST PART OF THE FORECAST AREA AROUND 200 PM. OTHER ISOLATED DEVELOPMENT WILL BE POSSIBLE ABOUT THE SAME TIME EAST OF THE CREST OF THE BLUE RIDGE WITHIN AN AXIS OF A LEE SIDE TROUGH. THE BETTER COVERAGE OF SHOWERS AND STORMS WILL ENTER THE NORTHWEST PART OF THE REGION MORE IN THE 5PM TO 6PM TIME FRAME. HAVE RAMPED UP PRECIPITATION CHANCES INTO THE LIKELY CATEGORY ACROSS THE NORTHERN HALF OF THE FORECAST AREA BETWEEN 6PM AND 9PM. AS WHAT IS EXPECTED TO BE A LINE OF CONVECTION WITH POTENTIALLY STRONG TO DAMAGING WINDS MOVES THROUGH THE AREA...A PREDOMINATELY WESTERLY FLOW WILL LIMIT COVERAGE IMMEDIATELY ALONG AND EAST OF THE CREST OF THE BLUE RIDGE. COVERAGE MAY INCREASE AGAIN ONCE ACTIVITY GETS EAST OF THE DANVILLE AREA. HIGH TEMPERATURES ARE STILL ON TRACK TO EARLIER FORECAST HIGHS...SO NO ADJUSTMENTS THERE. AS OF 945 AM EDT TUESDAY... THE LATEST FORECAST NEEDS NO MAJOR CHANGES AT THIS TIME. TIMING OF CONVECTION STILL LOOKS MOST PROBABLE STARTING AROUND THE MID- AFTERNOON AND ONWARD. HOT CONDITIONS STILL ARE LIKELY WITH NEAR RECORD HIGH TEMPERATURES FOR PARTS OF THE REGION. HAVE MADE MINOR TWEAKS TO THE HOURLY TEMPERATURE...DEW POINT...AND SKY COVER THROUGH THE EARLY AFTERNOON BASED UPON THE LATEST OBSERVATIONS AND EXPECTED TRENDS OVER THE NEXT TWO TO THREE HOURS. AS OF 150 AM EDT TUESDAY... AGAIN LOOKS TO BE THE HOTTEST DAY OF THE YEAR SO FAR THIS AFTERNOON WITH 85H TEMPS PUSHING +22-23C AIDED BY WESTERLY DOWNSLOPING AND COMPRESSION AHEAD OF THE FRONT APPROACHING FROM THE NORTH. THIS COMBINED WITH GOOD HEATING SHOULD PUSH SOME SPOTS TO NEAR 100 OUT EAST WITH EVEN A FEW LOW 90S MOUNTAINS. HOWEVER STILL APPEARS ENOUGH MIXING OUT OF DEWPOINTS LATER THIS AFTERNOON TO KEEP HEAT INDEX VALUES JUST BELOW CRITERIA. THUS WILL MENTION IN THE HWO BUT NOT HOIST ANY ADVISORY HEADLINES AT THIS POINT. OTHER BIGGER CONCERN WITH THE POTENTIAL STRONG TO SEVERE STORM THREAT AS CONVECTION LINES UP WITH THE PRE-FRONTAL TYPE OUTFLOW JUST AHEAD OF THE BOUNDARY HEADING IN FROM THE NW LATER ON. MODELS TENDING TO DEVELOP AT LEAST A BROKEN LINE JUST NW OF THE CWA BY MID AFTERNOON AND THEN SHIFT IT SE INTO HIGH INSTABILITY/DCAPES INCLUDING STEEP LAPSES AS THE FRONT JUMPS OUT TO THE LEE TROUGH. HOWEVER GUIDANCE DIFFERS ON HOW THIS BAND OF CONVECTION INTERACTS WITH THE DEEP...WELL MIXED WESTERLY FLOW REGIME WITH SOME SPLITTING ALONG THE BLUE RIDGE...AND OTHERS PROGRESSING ACROSS WHILE STRENGTHENING IN THE PIEDMONT AND OUT WEST. IF SLOWER... SIMILAR TO THE LATEST ENSEMBLES COULD SEE A LINE SWING THROUGH MUCH OF THE NORTH/NW CWA BY EARLY EVENING BEFORE SPLITTING IN TWO AS SUPPORTED BY THE HRRR WITH BEST COVERAGE NE WHERE FARTHER REMOVED FROM THE DOWNSLOPE...AND OVER THE FAR WEST PER CONVERGENCE. GIVEN SO MUCH WEST WIND AND NVA OVER THE REGION FOR MUCH OF THE DAY...TRENDED SLOWER WITH BRIEF LIKELY POPS FAR NW/NE...AND HIGHER CHANCES ELSW EAST OF THE BLUE RIDGE WHERE THE LOW LEVEL FLOW DOES BACK LATE. ALSO HIGHER CHANCES SE WEST VA SOUTH ALONG THE I-77 CORRIDOR WHERE OUTFLOW COULD SPARK SOME SHALLOW CONVECTION EARLY ON. OTRW APPEARS LOWEST POPS 20/30S NEW RIVER/ROANOKE VALLEYS PENDING TIMING AND DEGREE OF MIXING INTO EARLY EVENING. ALTHOUGH STRONGER WINDS ALOFT STAY TO THE NORTH...UNDIRECTIONAL FLOW COULD ALLOW FOR MULTICELL CLUSTERS/BANDS MAKING FOR DECENT DAMAGING WIND POTENTIAL IN THIS ENVIRONMENT IF STORMS CAN ORGANIZE. ADDITIONAL STRONGER STORMS MAY LINGER OVER THE SOUTH/SE THIS EVENING AND PERHAPS PERSIST IN SPOTS OVER THE FAR WEST/SW OVERNIGHT AS THE FRONT SAGS SOUTH BUT STALLS OUT CROSSING THE WEST. HOWEVER THINKING LOSS OF HEATING SHOULD PRECLUDE MUCH COVERAGE AFTER MIDNIGHT ESPCLY IF A LINE SWINGS THROUGH OR SPLITS SO ONLY LEAVING IN ISOLATED COVERAGE SOUTHERN/SW SECTIONS LATE. OTRW SOME CLEARING LIKELY IN ALL EXCEPT THE FAR WEST/SW GIVEN WESTERLY UPSLOPE FLOW...WITH PATCHY FOG AROUND UNDER MUGGY LOWS IN THE 65-70 RANGE WEST AND 68-74 EAST. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY/... AS OF 334 AM EDT TUESDAY... A COOL FRONT WILL SLIDE SOUTH AND STALL OVER THE CAROLINAS WEDNESDAY. MODELS ARE ALLOWING MORE DRY AIR THAN PREVIOUS RUNS TO ENTER THE AREA...ESPECIALLY ACROSS THE NORTH. DEW POINTS WEDNESDAY AFTERNOON COULD BE AS LOW AS THE MID 50S. NOT MUCH COOL AIR WITH THE FRONTAL PASSAGE AND WITH A HIGH SUMMER SUN AND DRY AIR...TEMPERATURES WILL WARM INTO THE 80S ACROSS THE MOUNTAINS TO THE LOWER TO MID 90S EAST. WITH THE PUNCH OF DRY AIR...THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS WILL BE LOW AND ISOLATED AT BEST. A SURFACE REFLECTION ALONG THE STALL FRONT OVER THE CAROLINAS WILL EDGE NORTHWARD ON THURSDAY. THIS REFECTION WILL BRING AN INCREASE IN MOISTURE AND THE CHANCES FOR AFTERNOON SHOWERS AND THUNDERSTORMS. FOR NOW...MODELS ARE INDICATING ANY CONVECTION THURSDAY WILL BE DIURNAL...BUT WE WILL NEED TO KEEP AN EYE TO THE NORTHWEST FOR ANY COMPLEXES DEVELOPING OVER THE UPPER MIDWEST AND OHIO VALLEY. TEMPERATURES THURSDAY WILL ONCE AGAIN BE WARMER THAN NORMAL WITH MID TO UPPER 80S WEST TO LOWER TO MID 90S EAST. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... AS OF 300 PM EDT MONDAY... UPPER FLOW CHANGES TO A MORE AMPLIFIED PATTERN IN THIS TIME FRAME...WITH A DEEP TROF OVER THE EASTERN UNITED STATES AND A STRONG RIDGE IN THE WEST. THIS WILL PROLONG THE CHANCE OF WIDESPREAD PRECIPITATION THROUGH AT LEAST SUNDAY. SURFACE LOW PRESSURE DEEPENS OVER THE TENNESSEE VALLEY ON SATURDAY THEN TRACKS TO OFF THE NEW JERSEY COAST BY LATE SUNDAY. WILL BE INCREASING THE PROBABILITY OF PRECIPITATION ACROSS THE FORECAST AREA FOR SATURDAY. ENOUGH CLOUDS...PRECIPITATION AND LOWER 500 MB HEIGHTS TO BRING TEMPERATURES BACK DOWN AROUND NORMAL FOR FRIDAY THROUGH SUNDAY. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... AS OF 640 AM EDT TUESDAY... OUTSIDE OF PATCHY MVFR/IFR IN FOG/STRATUS EARLY ON...EXPECTING VFR CONDITIONS TO RETURN BY MID MORNING WITH GOOD FLYING CONDITIONS CONTINUING INTO EARLY THIS AFTERNOON. THIS IN ADVANCE OF A WEAK COOL FRONT THAT WILL BE APPROACHING LATER IN THE DAY. ISOLATED SHOWERS OR STORMS MAY DEVELOP OR MOVE INTO THE KBLF-KLWB AREA AROUND 19Z/3PM. THE FRONT WILL APPROACH AND THEN CROSS THE AREA THIS EVENING AND OVERNIGHT. THIS SHOULD BRING CU BUILDUPS BY EARLY AFTERNOON WITH INCREASING CHANCES OF SHOWERS AND STORMS IN ASSOCIATION WITH THE FRONT. SOME OF THE STORMS MAY CONTAIN VERY STRONG WIND GUSTS. ALSO...BRIEF SUB-VFR CONDITIONS ARE EXPECTED UNDER THE HEAVIER CORES. APPEARS BEST CHANCES REMAIN OVER THE WEST AROUND KBLF/KLWB AND ACROSS THE NE AROUND KLYH WITH LESS AT KBCB/KROA DUE TO WESTERLY FLOW. KDAN MAY SEE A LINE OF STORMS CROSS THE REGION IN THE EVENING BUT WONT INCLUDE MENTION FOR NOW GIVEN UNCERTAINTY. OTRW DELAYED TIMING OF CONVECTION AN HOUR OR TWO MOST SPOTS AND KEPT MOSTLY VICINITY MENTION AT THIS POINT WITH SHOWERS INCLUDED WITHIN THE PREVAILING CONDITIONS AT KBLF/KLWB. MVFR SCTD TO BKN CLOUDS ARE POSSIBLE WITH LINGERING SHOWERS INCLUDING AREAS OF FOG LATER THIS EVENING INTO WEDNESDAY MORNING. EXTENDED AVIATION DISCUSSION... HIGH PRESSURE WILL BUILD INTO THE AREA FOR WEDNESDAY AND MUCH OF THURSDAY. HOWEVER...THE FRONT FROM TUESDAY WILL STILL BE NEAR THE SOUTHERN EDGE OF OUR REGION...AND BECOME STALLED. IN ADDITION...AN UPPER TROUGH WILL BE POSITIONED ACROSS THE NORTHEAST U.S. THESE FEATURES WILL CONTINUE TO SERVE AS THE FOCUS FOR ADDITIONAL SHOWERS AND STORMS BY THURSDAY EVENING. FRIDAY INTO SATURDAY...A SHORTWAVE TROUGH RIDES SOUTHEAST ALONG THE ESTABLISHED BAROCLINIC ZONE...AND HELPS TO CARVE OUT AN EVEN DEEPER EAST COAST TROUGH. LOOK FOR INCREASED COVERAGE OF SHOWERS AND STORMS WITH A GREATER RANGE OF REAL ESTATE THAT WILL EXPERIENCE SUB-VFR CIGS AND VSBYS. && .CLIMATE... RECORD HIGH TEMPERATURES ARE POSSIBLE TODAY. BELOW ARE THE CURRENT RECORDS FOR THE DATE. JUNE 23 CITYTEMPYEAR BLF901988 DAN1001988 LWB911988 LYH981911 BCB921988 ROA981914 && .EQUIPMENT... THE NOAA WEATHER RADIO IN LYNCHBURG...BROADCASTING ON A FREQUENCY OF 162.550 MHZ...IS WORKING ON THE SECONDARY TRANSMITTER. TECHNICIANS CONTINUE TO WORK ON THE ISSUE AND HAVE ADVISED THAT BOTH TRANSMITTERS WONT BE FULLY OPERATIONAL UNTIL THURSDAY. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...NONE. NC...NONE. WV...NONE. && $$ SYNOPSIS...DS/JH NEAR TERM...DS/JH SHORT TERM...RCS LONG TERM...AMS AVIATION...DS/JH/KK CLIMATE...CF EQUIPMENT...DS
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
341 PM CDT TUE JUN 23 2015 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 341 PM CDT TUE JUN 23 2015 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED SUBTROPICAL RIDGING ENCOMPASSING THE SOUTHERN U.S.. WHILE A WEST-NORTHWEST FLOW RUNS FROM THE PACIFIC NORTHWEST INTO THE MID- ATLANTIC. THE TWO MAIN SHORTWAVES OF NOTE WERE OVER THE SIOUX FALLS AREA AND SOUTHERN BRITISH COLUMBIA. THE ONE IN SIOUX FALLS ALONG WITH A WIDE AREA OF LOW TO MID LEVEL FRONTOGENESIS WAS HELPING TO PRODUCE PLENTY OF ALTOSTRATUS FROM SOUTH DAKOTA/NEBRASKA EAST INTO THE SOUTHERN PORTION OF THE FORECAST AREA. AIRMASS HAS BEEN TOO DRY TO SUPPORT ANY PRECIPITATION DESPITE SEEING ECHOES ON RADAR...AS REFLECTED BY THE 12Z MPX SOUNDING WITH A 700MB DEWPOINT DEPRESSION OF 40C. ONLY A VERY FEW SITES HAVE REPORTED SPRINKLES. MAIN SURFACE FRONTAL BOUNDARY ASSOCIATED WITH THE FRONTOGENESIS WAS WELL TO THE SOUTH...SITUATED JUST SOUTH OF I-70 AND WAS VERY SLOWLY LIFTING NORTH TODAY. THAT NORTHWARD PROGRESS HAS BEEN HELD BACK BY A PERSISTENT COMPLEX OF CONVECTION FROM SOUTHEAST NEBRASKA INTO THE KANSAS CITY AREA. SUNSHINE TODAY COMBINED WITH 850MB TEMPS AROUND 10C HAS RESULTED IN HIGHS MOSTLY IN THE 70S. MUCH LOWER DEWPOINTS TODAY THAN YESTERDAY WITH MIXING AND DRY AIR RESULTING IN READINGS OF 45 TO 55F. LOOK FOR A CONTINUATION OF QUIET CONDITIONS TONIGHT ACROSS THE FORECAST AREA AS THE AREA OF HIGH PRESSURE HELPING TO PROVIDE THE DRY CONDITIONS ONLY DRIFTS OFF TO THE SOUTHEAST. WE WILL HAVE TO DEAL WITH THE SOME HIGHER BASED FRONTOGENESIS...YIELDING SOME ALTOSTRATUS AS WE ARE SEEING TODAY. THESE CLOUDS SHOULD HELP TO PRECLUDE FOG FORMATION...AND ALSO KEEP TEMPERATURES FROM FALLING BELOW THE MID 50S. THE MORE INTERESTING PART OF THE SHORT TERM IS FOR WEDNESDAY. MODELS CONTINUE TO ADVERTISE THAT THE FRONTAL BOUNDARY IN KANSAS WILL LIFT NORTHWARD OVER THE NEXT 24 HOURS...IN RESPONSE TO A MONSOONAL SHORTWAVE COMING OUT OF COLORADO AND ROTATING AROUND THE SOUTHERN U.S. SUBTROPICAL RIDGE. AS THIS OCCURS WITH THE NOCTURNAL LOW LEVEL JET...MODELS ARE ADVERTISING AT LEAST CONVECTION IF NOT AN MCS TO DEVELOP OVER EASTERN NEBRASKA AND WESTERN IOWA LATE TONIGHT. CORFIDI VECTORS WOULD TAKE THIS MCS INTO NORTHERN MO WEDNESDAY MORNING... HOLDING THE FRONT BACK. HOWEVER...SOME GUIDANCE LIKE THE 23.12Z GFS/NAM WANT TO KEEP MOVING THE FRONT NORTH INTO THE AFTERNOON... SPREADING EITHER PREVIOUS OR NEW CONVECTION INTO NORTHEAST IA AND SOUTHWEST WI. BELIEVE THIS IS GOING TO BE TOUGH AS CLOUD DEBRIS LIMITS DAYTIME MIXING...AND CONVECTIVE OUTFLOW HOLDS THE BOUNDARY BACK. MORE LIKELY...WHEN NEW CONVECTION FIRES IT WILL BE FARTHER SOUTH CLOSER TO THE FRONT...WHICH SHOULD BE HUNG UP NEAR THE MO/IA BORDER BY 00Z THU. THE 23.12Z ECMWF REMAINS THE FARTHEST SOUTH MODEL WITH THE FRONT AND CONVECTION...AND SEEMS MOST REASONABLE GIVEN EXPECTED CONVECTION TRACKS. THEREFORE...PRECIPITATION CHANCES ARE HIGHEST IN NORTHEAST IA BUT STILL ONLY AS MUCH AS 50 PERCENT BY LATE IN THE DAY GIVEN ANTICIPATION FOR MOST CONVECTION TO STAY SOUTH. GIVEN THE MAJORITY OF CAPE TO STAY WELL SOUTH OF THE AREA...THE SLIGHT RISK ON SPCS DAY 2 OUTLOOK WAS SHIFTED MOSTLY OUT OF THE FORECAST AREA. ITS WORTH NOTING THAT MODELS...OUTSIDE THE 23.12Z ECMWF...HAVE REALLY STRUGGLED WITH THE ONGOING CONVECTION NORTH OF THE FRONT IN THE KANSAS CITY AREA. THERE IS ALSO SOME CONCERN FOR SHOWERS AND STORMS TO FIRE NORTH OF HIGHWAY 29 WEDNESDAY AFTERNOON...RELATED TO THE SHORTWAVE IN BRITISH COLUMBIA HEADING INTO NORTHERN PORTIONS OF MN OR WI. THE ECMWF IS SLOWEST WITH THE SHORTWAVE AND THEREFORE IS DRY...WHEREAS THE GFS AND NAM ARE FASTER AND HAVE PRECIP. THE GFS/NAM ALSO HAVE HIGHER SURFACE DEWPOINTS WHICH SEEM TOO HIGH. THEREFORE...HAVE ONLY KEPT A 20 PERCENT CHANCE IN TAYLOR COUNTY LATE IN THE DAY. WITH 850MB TEMPS IN THE 12-14C RANGE AND SOME SUN LIKELY FOR AT LEAST THE MORNING HOURS...HIGHS SHOULD PUSH INTO THE MID 70S TO LOW 80S...WARMEST TO THE NORTH WHERE LONGER PERIOD OF SUN IS EXPECTED. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 341 PM CDT TUE JUN 23 2015 23.12Z ECMWF/GFS/CANADIAN MAINTAIN THE SAME LONG WAVE PATTERN THEY HAVE BEEN SHOWING THE PAST SEVERAL DAYS...WITH STRONG SUBTROPICAL RIDGING SHIFTING AND BUILDING OVER THE WESTERN U.S. ON THURSDAY...CAUSING FAIRLY DEEP TROUGHING FOR THIS TIME OF YEAR OVER THE EASTERN U.S.. THIS SHIFT IS IN RESPONSE TO THE MADDEN JULIAN OSCILLATION GOING INTO AN ANOMALOUSLY STRONG PHASE 6. WHAT THIS MEANS FOR THE FORECAST AREA IS TEMPERATURES TO HOLD AT OR NEAR SEASONABLE NORMALS...WITH PERHAPS A SLOW WARMUP LATE IN THE WEEKEND INTO EARLY NEXT WEEK. ANY GULF OF MEXICO RETURN OF MOISTURE SHOULD GET SHUTOFF WITH MOISTURE SOURCES MOSTLY TURNING TO EVAPOTRANSPIRATION AND WHAT SYSTEMS CAN BRING OFF THE PACIFIC DOWN THE RIDGE. THE MAIN FOCUS FOR PRECIPITATION REMAINS WEDNESDAY NIGHT. HOWEVER...SIMILAR TO WEDNESDAY...HOW FAR NORTH THE WARM FRONT NEAR THE IA/MO BORDER AT 00Z THU REALLY DETERMINES THE CONVECTION CHANCES. CURRENT THINKING LIES ALONG THE MORE PREFERRED ECMWF VERSUS THE BIASED NORTH GFS/NAM/SREF/CANADIAN...WHICH SUGGESTS ANOTHER MCS FORMING OVER CENTRAL IOWA WEDNESDAY EVENING...MARCHING LIKELY SOUTHEASTWARD FOLLOWING CORFIDI VECTORS. THIS IS IN LINE WITH THE HIGHEST SPC DAY 2 OUTLOOK PROBABILITIES. THE NORTHERN PART OF THIS MCS COULD CLIP OUR FAR SOUTH...THUS HAVE THE HIGHEST 50-60 PERCENT CHANCES THERE FOR THE EVENING. TRIMMED CHANCES BACK FARTHER NORTH AND AREAS NORTH OF U.S. HIGHWAY 18 MAY END UP DRY. THE LONE EXCEPTION WOULD BE NORTH OF HIGHWAY 29...CLOSER TO THAT SHORTWAVE TROUGH MARCHING ACROSS MN AND NORTHERN WI. PRECIPITATION SHOULD DIMINISH WEST TO EAST DURING THE OVERNIGHT HOURS AS THE MCS AND SHORTWAVE TROUGHS MOVE FURTHER AWAY FROM THE AREA. FOR THURSDAY AND FRIDAY...THE 23.12Z GFS AND TO A LESSER EXTENT THE NAM WANT TO FIRE UP SOME DIURNAL SHOWERS AND STORMS...ASSOCIATED WITH WEAK SHORTWAVES DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z ECMWF SHOWS THESE SAME SHORTWAVES BUT IS DRY. MUCH OF THE DIFFERENCE RELATES TO BOUNDARY LAYER MOISTURE AND ITS IMPACT TO CAPE. AT BOTH 00Z FRI AND 00Z SAT...THE GFS IS NEARLY 10F HIGHER ON SURFACE DEWPOINTS TO THE ECMWF. THINKING THE ECMWF IS MORE CORRECT AND THUS HAVE ONLY 20-30 PERCENT CHANCES AT MOST...HIGHEST IN WESTERN AREAS. SATURDAY LOOKS DRY WITH HIGH PRESSURE IN PLACE...BUT THEN THERE IS AN ISSUE WITH SUNDAY INTO MONDAY WITH MODELS TIMING A STRONGER SHORTWAVE TROUGH DROPPING THROUGH THE NORTHWEST FLOW. THE 23.12Z ECMWF IS FASTEST AND SPREADS SOME CONVECTION ACROSS THE AREA ON SUNDAY...WHEREAS THE 23.12Z CANADIAN/GFS WAIT UNTIL EITHER LATER SUNDAY NIGHT OR MONDAY. GIVEN THE SPREAD...HAVE KEPT A 20-40 PERCENT CHANCE FOR ALL 3 12 HOUR TIME PERIOD. NEEDLESS TO SAY A GOOD PORTION CAN PROBABLY BE DRIED OUT IN LATER FORECASTS ONCE THE TIMING GETS RESOLVED. ANOTHER NORTHWEST FLOW WAVE IS PROGGED FOR TUESDAY... RESULTING IN MORE CHANCES OF PRECIPITATION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1233 PM CDT TUE JUN 23 2015 THROUGH THE TIME PERIOD...KRST WILL BE AFFECTED BY STRONG 500 TO 600 MB FRONTOGENESIS BAND. THIS WILL KEEP A BROKEN 12-20K FOOT DECK OF CLOUDS AT THE SITE. MEANWHILE AT KLSE...THIS FRONTOGENETIC BAND LOOKS TO SAY SOUTH OF THE AIRPORT THROUGH TONIGHT AND THEN IT MOVES NORTH ON WEDNESDAY MORNING. WINDS AT BOTH TAF SITES WILL GRADUALLY VEER FROM NORTHWEST TO SOUTH BY THIS EVENING AND REMAIN IN THAT DIRECTION THROUGH WEDNESDAY MORNING. WIND SPEEDS WILL REMAIN LESS THAN 10 KNOTS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
253 PM MDT TUE JUN 23 2015 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 200 PM MDT TUE JUN 23 2015 VERY CONDITIONAL FORECAST FOR THIS EVENING INTO WEDNESDAY. FORECAST CHALLENGES DEAL WITH TIMING/LOCATION OF CONVECTION TONIGHT INTO WEDNESDAY MORNING. CURRENTLY...VERY HIGH DEW POINTS BEING OBSERVED ACROSS THE PANHANDLE WESTWARD TO THE LARAMIE RANGE EARLY THIS AFTERNOON. DEW POINTS RANGE FROM 61 AT SIDNEY...TO 60 AT CHEYENNE TO 55 AT DOUGLAS AT 1PM. WATER VAPOR IMAGERY SHOWING THE ANTICIPATED UPPER LEVEL SHORTWAVE CURRENTLY IN SOUTHERN IDAHO THIS AFTERNOON MOVING AT A FAIRLY GOOD CLIP DUE EAST INTO WEST CENTRAL WYOMING. VISIBLE SATELLITE IMAGERY STARTING TO SHOW ISOLATED CU DEVELOPMENT OVER THE NORTHERN PANHANDLE AND POSSIBLY AROUND THE LARAMIE AREA/SOUTH LARAMIE RANGE. THE ATMOSPHERE IS STRONGLY CAPPED THIS AFTERNOON EAST OF THE LARAMIE RANGE. LATEST NAM SOUNDINGS SHOWING RIGHT AROUND 750MB HERE AT CHEYENNE...730MB AT CHADRON. FORECAST SOUNDINGS KEEP THIS CAP IN PLACE AT LEAST UNTIL AFTER 00Z WITH CONVECTIVE INHIBITION ANYWHERE FROM -60 J/KG HERE AT CHEYENNE TO -100 J/KG AT CHADRON FROM SPC`S PAGE. GOING TO TAKE A WHILE TO BREAK THIS CAP...IF WE DO IT AT ALL. DO THINK CURRENT IDEA OF LATE DEVELOPMENT OF THUNDERSTORMS IS STILL ON TRACK. WITH THE APPROACH OF THE UPPER SHORTWAVE THIS EVENING...LAPSE RATES SHOULD CONTINUE TO STEEPEN. ALREADY SEEING THESE STEEP LAPSE RATES IN WESTERN WYOMING AHEAD OF THAT SHORTWAVE. LATEST HRRR CONVECTIVE SIMULATION SHOWING CONVECTION BEGINNING TO BREAK OUT AFTER 00Z NEAR LUSK UP INTO NORTHEASTERN WYOMING. ALSO SHOWING A PRETTY STRONG CELL DEVELOPING FURTHER SOUTH NEAR CHEYENNE AND MOVING INTO THE SOUTHERN PANHANDLE. SO DO FEEL THE LATEST SPIC SLIGHT RISK AREA IS STILL IN GOOD SHAPE. WILL CONTINUE TO ADVERTISE SEVERE THUNDERSTORMS TONIGHT INTO EARLY WEDNESDAY MORNING. GFS AND ECMWF QPF OUTPUT HAS CONVECTION PERSISTING INTO 12Z BEFORE FINALLY ENDING AS THE SHORTWAVE MOVES EAST OF THE FORECAST AREA. DO HAVE ANOTHER FAIRLY VIGOROUS SHORTWAVE THURSDAY AFTERNOON THAT COULD KICK OFF SCATTERED SHOWERS. TIMING IS PERFECT FOR AFTERNOON AND EVENING ISOLATED SEVERE STORMS ONCE AGAIN. .LONG TERM...(FRIDAY THROUGH TUESDAY) ISSUED AT 250 PM MDT TUE JUN 23 2015 THE LAST OF A SERIES OF DISTURBANCES WILL EXIT INTO THE EASTERN GREAT PLAINS FRIDAY WITH ISOLATED AFTERNOON CONVECTION OVER FAR SOUTHEAST WY AND WESTERN NE. NORTHWEST TO NORTH FLOW IN THE MID/UPPER LEVELS WILL PREVAIL THIS WEEKEND INTO EARLY NEXT WEEK AS THE WESTERN CONUS RIDGE BUILDS INTO THE ROCKY MOUNTAINS REGION AND HIGH PLAINS. THE MODELS...PARTICULARLY THE GFS...CONTINUE TO DEPICT SOME LIGHT QPF ASSOCIATED WITH DIURNALLY-DRIVEN CONVECTION OVER THE SOUTHEAST WY MOUNTAINS THIS WEEKEND. COVERAGE WILL BE ISOLATED. THE PLAINS WILL BE VOID OF CONVECTION AS THE MID LEVELS WARM. HIGH TEMPERATURES WILL BE WARMING A FEW DEGREES EACH DAY. CONVECTIVE INHIBITION INCREASES MORESO EARLY WEEK WITH STOUT MID LEVEL CAP. THE UPSHOT IS A DRY AND WARM FORECAST FOR MONDAY AND TUESDAY WITH MOSTLY CLEAR SKIES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1131 AM MDT TUE JUN 23 2015 VFR CONDITIONS WILL PREVAIL THIS AFTERNOON AND EVENING. ISOLATED TSTORM ACTIVITY EXPECTED TO DEVELOP LATE AFTERNOON OVER THE LARAMIE RANGE...BECOMING SCATTERED AS IT MOVES EAST ONTO THE PLAINS THIS EVENING AND LATE TONIGHT. CONFIDENCE NOT HIGH ENOUGH FOR STORMS AT ANY PARTICULAR AERODROME...SO MENTIONED VETS FOR THIS TAF PACKAGE. NEXT SHIFT CAN FINE TUNE TIMING AND IMPACT OF STORMS. ATOM...BEST CHANCES WILL BE EAST OF A DOUGLAS TO SCOTTSBLUFF LINE. THE SREF...NAM AND GFS ALL INDICATE LOWERING CIGS AND VSBY ACROSS WESTERN NE AFTER 09Z WHEN CONVECTION ENDS. && .FIRE WEATHER... ISSUED AT 200 PM MDT TUE JUN 23 2015 PRETTY DRY CONDITIONS ACROSS CARBON COUNTY AND AREAS WEST OF THE LARAMIE RANGE. AFTERNOON HUMIDITIES AGAIN EXPECTED TO FALL TO CRITICAL LEVELS THIS AFTERNOON AND AGAIN WEDNESDAY FOR ZONES 303...304...306 AND POSSIBLY 308. AFTERNOON WIND GUSTS TO 25-30 MPH IN THESE LOCATIONS COULD CREATE ISOLATED AREAS OF CRITICAL FIRE WEATHER CONDITIONS. BUT SINCE MOST AREAS ARE STILL GREEN ON FUELS...FIRE WEATHER CONCERNS REMAIN LOW. BETTER CHANCES FOR WIDESPREAD WETTING RAINS THURSDAY AS AN UPPER LEVEL DISTURBANCE MOVES INTO THE AREA FROM THE NORTHWEST AND INTERACTS WITH THE STALLED FRONT ALONG THE LARAMIE RANGE. WETTING RAINS EXPECTED FROM LARAMIE EAST INTO THE PANHANDLE. MORE DRIER...HIGH BASED THUNDERSTORMS FOR CARBON COUNTY THURSDAY AFTERNOON/EVENING. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...NONE. NE...NONE. && $$ SHORT TERM...GCC LONG TERM...MAJ AVIATION...MAJ FIRE WEATHER...GCC