Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 10/02/14


AREA FORECAST DISCUSSION
NWS PUEBLO CO
ISSUED BY NATIONAL WEATHER SERVICE DENVER CO 319 PM MDT TUE SEP 30 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 319 PM MDT TUE SEP 30 2014 SATELLITE IMAGERY SHOWS A SHORT WAVE MOVING OVER THE SAN JUAN MOUNTAINS AND CENTRAL PART OF THE STATE AT THE PRESENT TIME. THE RAP AND HRRR MODELS HAVE BEEN INDICATING A ROUND TO SHOWERS DEVELOPING OVER THE EAST-CENTRAL PLAINS THROUGH THIS EVENING. WILL MENTION ISOLATED SHOWERS THROUGH THE EVENING HOURS. THE SAN JUANS AND NORTHERN SANGRE DE CRISTOS WILL ALSO SEE A FEW SHOWERS. OVER THE SAN LUIS VALLEY...SKIES SHOULD CLEAR OUT AFTER PASSAGE OF THE SHORT WAVE...ALLOWING TEMPERATURES TO DROP DOWN TO THE UPPER 20S AND LOWER 30S. WILL KEEP THE FROST ADVISORY IN EFFECT THAT HAS BEEN IN EFFECT GOING OVERNIGHT. ANOTHER SHORT WAVE WILL MOVE OVER THE STATE ON WEDNESDAY. MOST OF THE SHOWER ACTIVITY WITH THIS DISTURBANCE WILL MOVE ACROSS NORTHERN COLORADO...BUT THE CENTRAL MOUNTAINS AND PALMER DIVIDE REGION COULD ALSO PICKUP ANOTHER ROUND OF SHOWERS THROUGH THE DAY. INCREASED CLOUD COVER WILL HELP TO HOLD TEMPERATURES AROUND WHERE THEY WERE TODAY. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 319 PM MDT TUE SEP 30 2014 THE FINAL SHORT WAVE WILL BE MOVING OUT OF THE STATE WEDNESDAY EVENING WITH RISING HEIGHTS ACROSS THE STATE AFTER THAT. THE AIRMASS WILL BE DRYING AND WARMING THROUGH THE REST OF THE WEEK AND INTO THE WEEKEND. WEATHER WILL BE DRY WITH TEMPERATURES EVENTUALLY WARMING TO ALMOST 10 DEGREES WARMER THAN SEASONAL NORMALS EARLY NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 319 PM MDT TUE SEP 30 2014 ORGANIZED SHORT WAVE MOVING OVER THE SAN JUAN MOUNTAINS THIS AFTERNOON LOOKS LIKE IT MIGHT HAVE ENOUGH ORGANIZATION TO BRING A ROUND OF SHOWERS ACROSS EL PASO AND PUEBLO COUNTIES AFTER ABOUT 01Z. TAFS WILL MENTION VCSH FOR A FEW HOURS AFER 01Z. ANOTHER SHORT WAVE EXPECTED TO BE MOVING OVER THE STATE TOMORROW WILL LIKELY GENERATE ADDITIONAL SHOWER OR THUNDERSTORM ACTIVITY DURING THE AFTERNOON HOURS. && .PUB WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY FROM 2 AM TO 8 AM MDT WEDNESDAY FOR COZ069>071. && $$ SHORT TERM...DANKERS LONG TERM...DANKERS AVIATION...DANKERS
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
1058 AM MDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1057 AM MDT TUE SEP 30 2014 FORECAST ON TRACK WITH GUSTY WINDS IN/NEAR THE FRONT RANGE MOUNTAINS AND FOOTHILLS...AS WELL AS THE NORTHERN BORDER AREA. THE STRONGEST WINDS WILL BE CONFINED TO THOSE AREAS THROUGH THE AFTERNOON. GUSTS TO 50 MPH EXPECTED ABOVE TIMBERLINE WITH 30 TO 40 MPH GUSTS NEAR THE WYOMING BORDER. HOWEVER...THEY WILL GRADUALLY WEAKEN THROUGH THE COURSE OF THE AFTERNOON AS CROSS MOUNTAIN COMPONENT EASES. MEANWHILE...WITH INCREASED MIXING WE DO EXPECT CHANNELS OF WESTERLY WINDS TO SPREAD ONTO THE PLAINS. AT THE SAME TIME SOME LOCATIONS COULD REMAIN EASTERLY IN THIS CURRENT WEATHER SCENARIO SINCE STRONGEST DOWNWARD FORCING IS PUSHING EAST OF THE FORECAST AREA. MAIN CHANGE WAS TO ADD SOME LOW POPS ON THE PLAINS BY THIS EVENING AS LATEST MODEL RUNS ARE SHOWING A BIT OF CAPE AND ENOUGH HEATING TODAY TO SUFFICIENTLY MIX OUT STABLE LAYER. IN ADDITION...THE WEAK WAVE MOVING ACROSS UTAH MAY PROVIDE SUFFICIENT COOLING TO ALLOW A FEW SHOWERS TO SPREAD ONTO THE PLAINS. ALSO BUMPED UP POPS IN THE MOUNTAINS FOR OROGRAPHICS COMBINING WITH WEAK LIFT THROUGH TONIGHT. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 400 AM MDT TUE SEP 30 2014 DEEP UPPER AIR CYCLONE CENTERED OVER EXTREME NWRN NEBRASKA AT THIS HOUR WILL CONTINUE TO QUICKLY TRACK NORTH-NORTHEASTWARD ACRS NORTH DAKOTA THIS MORNING AND THEN UP OVER MANITOBA LATER TODAY. STRONG MID-LEVEL SUBSIDENCE ON THE BACK SIDE OF THIS DEPARTING LOW PRES SYSTEM WAS NOW OVER COLORADO. NAM AND RAP QG VERT VELOCITY FIELDS AND ON H2O VAPOR SAT IMAGERY NICELY REVEAL THIS SINKING. STABILIZATION OF THE MTN TOP LAYER PAST FEW HOURS HAS PRODUCE A STANDING MTN WAVE ALONG THE FRONT RANGE...RESULTING IN GUSTY WEST-NORTHWEST WINDS AT HIGHER ELEVATIONS OF THE FRONT RANGE. NAM AND RAP CROSS SECTIONS INDICATE CROSS BARRIER WINDS IN THE 45-55KT RANGE BY AROUND 12Z THIS MORNING...THEN ONLY SLIGHTLY WEAKER AT 15Z. WIND SENSORS ATOP THE HIGH RIDGES WERE ALREADY INDICATING GUSTS IN THE 45-55 MPH RANGE. COULD SEE SOME OF THIS MOMENTUM SPREADING TO LOWER EAST SLOPES OF THE FRONT RANGE DURING THE NEXT FEW HOURS. DO NOT SEE WINDS REACHING HIGH WIND CRITERIA AT THIS TIME. FURTHERMORE...DO NOT ANTICIPATE THESE STRONG WINDS WILL SPREAD OUT ONTO THE NEARBY THE PLAINS. ALTHOUGH THE NORTHEAST CORNER OF THE CWA COULD SEE W-NWLY WIND GUSTS TO 40 MPH LATE THIS MORNING AND EARLY THIS EVENING WITH MOMENTUM MIXING DOWN FROM ALOFT. CLEARING EARLY THIS MORNING WILL GIVE WAY TO INCREASING MID AND HIGH CLOUDS EAST OF THE MTNS LATER TODAY. CLOUDY SKIES WILL ALSO RETURN TO AREAS ALONG AND WEST OF THE CONTINENTAL DIVIDE WITH A WEATHER DISTURBANCE RACING IN FROM THE NORTHWEST. QG VV REVERSE AND GO POSITIVE THIS AFTERNOON AS THIS NEXT WAVE OF MOISTURE AND ENERGY NEARS. COULD SEE SCATTERED SHOWERS AND ISOLATED T-STORMS IN THE MTNS AND HIGH VALLEYS BY MID- TO LATE AFTERNOON. SNOW LEVEL WILL HOOVER AROUND 11 THSND FT TODAY...AND DROP TO AROUND 9500 FT THIS EVENING. HOWEVER ANY SNOW ACCUMULATION SHOULD BE MINIMAL. BY EVENING SKIES SHOULD ALSO FILL WITH CLOUDS EAST OF THE MTNS AS THIS WEAK PERTABATION PASSES BY...THEN PARTIAL CLEARING LATE WITH ITS DEPARTURE. PCPN IS NOT ANTICIPATED THRU 12Z/WED EAST OF THE MTNS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 400 AM MDT TUE SEP 30 2014 THE NEXT UPPER LEVEL TROF WILL MOVE ACROSS COLORADO ON WEDNESDAY AFTERNOON AND NIGHT. AN ASSOCIATED COLD FRONT WILL MOVE ACROSS NORTHEAST COLORADO DURING THE AFTERNOON HOURS WITH INCREASING NORTHERLY FLOW AT LOW LEVELS. QG FIELDS SHOWING INCREASING ASCENT DURING THE DAY WEDNESDAY...PEAKING OVER THE FRONT RANGE IN THE AFTERNOON AND FURTHER EAST ON THE PLAINS DURING THE EARLY EVENING. SHORT RANGE MODELS ARE FAIRLY CONSISTENT ON TIMING WITH THIS TROF. GIVEN THE FRONT AND FORCING ALOFT WILL BUMP POPS UP FURTHER TO LIKELY OVER MOST SECTIONS DURING WEDNESDAY AFTERNOON AND EVENING. THE TROF IS QUITE PROGRESSIVE SO SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST WEDNESDAY NIGHT AS PRECIP DURATION WILL BE IN THE 3-6 HOUR RANGE. THE AIRMASS WILL BE COLD ENOUGH TO SUPPORT SOME SNOW ACCUMULATION IN THE MOUNTAINS. FOR THURSDAY AND BEYOND...THERE WILL BE A DRYING AND WARMING TREND AS COLORADO WILL BE UNDER A MODERATE...NORTHWEST FLOW PATTERN. && .AVIATION...(FOR THE TAFS THROUGH 18Z WEDNESDAY MORNING) ISSUED AT 1057 AM MDT TUE SEP 30 2014 WIND DIRECTION FORECAST WILL BE A CHALLENGE THROUGH THE AFTERNOON WITH POTENTIAL FOR CHANNELS OF WESTERLY WINDS TO MOVE OFF THE FOOTHILLS. AT THE SAME TIME...THERE WILL BE SOME DIURNAL EASTERLIES THAT THE WESTERLY WINDS WILL BE BATTLING THROUGH 00Z. WEST WINDS COULD GUST TO AROUND 18 KTS WHILE ANY EASTERLIES WILL BE LIGHTER AROUND 5-10 KTS. AFTER 00Z...WINDS ARE EXPECTED TO TRANSITION TO NORMAL DIURNAL SOUTH/SOUTHEWESTERLIES NEAR 10 KTS. LOW CHANCE OF A LIGHT RAIN SHOWER 00Z-05Z BUT CEILINGS WILL REMAIN HIGH ENOUGH FOR VISUAL LANDING CONDITIONS. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...BARJENBRUCH SHORT TERM...BAKER LONG TERM...ENTREKIN AVIATION...BARJENBRUCH
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1031 AM MDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1031 AM MDT TUE SEP 30 2014 NO CHANGES TO THE FORECAST PACKAGE FORTHCOMING. A TRAILING UPPER DISTURBANCE ROTATING THROUGH THE UPPER TROUGH OVER COLORADO TODAY LOOKS LIKE IT WILL HAVE ENOUGH STRENGTH TO PRODUCE A FEW MORE SHOWERS OVER THE NORTHWEST PORTIONS OF THE FORECAST AREA THIS AFTERNOON AND EVENING. PARK AND CHAFFEE COUNTIES LOOK LIKE THEY WILL HAVE THE BEST SHOT AT SHOWERS. THE HRRR MODEL ALSO DEVELOPS A BAND OF SHOWERS OVER PUEBLO COUNTY AFTER 01Z...BUT THE RAP KEEPS THE PLAINS DRY. WILL FAVOR THE RAP SOLUTION...SINCE IT APPEARS THERE WILL BE QUITE A BIT OF DOWNSLOPE SUBSIDENCE ALONG AND EAST OF THE FOOTHILLS. ANOTHER ROUND OF SHOWERS WILL BE POSSIBLE LATE TONIGHT AND TOMORROW MORNING AS THE LAST VORT MAX IN THE UPPER TROUGH ROTATES OVER THE NORTHERN HALF OF THE STATE. FROST ADVISORY FOR THE SAN LUIS VALLEY TONIGHT WILL REMAIN IN EFFECT. UPDATE ISSUED AT 648 AM MDT TUE SEP 30 2014 REINITIALIZED FRONT END GRIDS WITH LATEST OBSERVATIONS. WFO BOU WILL BE PROVIDING FULL SERVICE BACKUP FOR US TODAY STARTING AT APPROXIMATELY 7 AM MDT WHILE WFO PUEBLO UNDERGOES A MAJOR COMPUTER UPGRADE. WFO PUB SHOULD BE BACK IN CONTROL BETWEEN 3 PM AND 6 PM TODAY. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 343 AM MDT TUE SEP 30 2014 ...ISOLATED MOUNTAIN SHOWERS WITH SEASONAL TEMPERATURES... SYSTEM THAT MOVED THROUGH YESTERDAY HAS BROUGHT A SEASONAL AIR MASS TO SOUTHERN COLORADO. TODAY WILL BE A SEASONAL FALL DAY ACROSS THE AREA WITH A FEW MOUNTAIN SHOWERS AND ISOLATED AFTERNOON AND EVENING THUNDERSTORMS POSSIBLE...MAINLY OVER THE CONTINENTAL DIVIDE...AND MAINLY OVER THE CENTRAL MOUNTAINS. SNOW SHOWERS WILL BE POSSIBLE ABOVE ROUGHLY 10000 FEET TODAY WITH LOCAL ACCUMULATIONS OF AN INCH OR SO POSSIBLE AT PASS LEVEL AND ABOVE. AN ISOLATED SHOWER OR STORM COULD DRIFT OFF THE MOUNTAINS ONTO THE PLAINS LATE IN THE DAY OR EARLY IN THE EVENING. BUT THIS WOULD REALLY BE THE EXCEPTION RATHER THAN THE RULE. IN GENERAL...MOSTLY SUNNY OR PARTLY CLOUDY AT TIMES WITH SEASONAL TEMPERATURES TODAY. CURRENT FROST ADVISORY FOR THE SAN LUIS VALLEY CONTINUES TO LOOK GOOD FOR THIS MORNING. THE VALLEY HAS HAD SOME MOISTURE OVER THE PAST COUPLE DAYS AND TEMPERATURES ARE CURRENTLY IN THE MID TO UPPER 30S UNDER CLEAR SKIES. DEWPOINTS ARE CURRENTLY IN THE LOWER 30S. EXPECT TEMPERATURES TO FALL TO NEAR THE DEWPOINTS BY MORNING...WHICH WOULD MEAN LOWS NEAR FREEZING...NEAR SATURATED CONDITIONS...AND THUS A FROST. THE VALLEY WILL LIKELY SEE ANOTHER FROST TONIGHT...SO WILL GO AHEAD AND HOIST ANOTHER FROST ADVISORY FOR THEN. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 343 AM MDT TUE SEP 30 2014 NOT MUCH CHANGE TO THE LONG RANGE FORECAST WITH LOW ENSEMBLE SPREADS AND GOOD OPERATIONAL MODEL AGREEMENT THROUGH THE EXTENDED PERIOD. WEDNESDAY AND THURSDAY...A STRONG SHORTWAVE TROUGH WILL DROP SOUTH OUT OF THE NORTHERN ROCKIES AND MOVE ACROSS COLORADO. EXPECT ISOLATED TO SCATTERED SHOWER ACTIVITY ALONG THE CONTINENTAL DIVIDE WEDNESDAY MORNING WHICH WILL INCREASE IN COVERAGE AND SPREAD EAST INTO THE PALMER DIVIDE WEDNESDAY AFTERNOON. AFTERNOON INSTABILITY WILL LIKELY PRODUCE AT LEAST A FEW THUNDERSTORMS WEDNESDAY OVER THE MOUNTAINS WITH LIGHTNING BEING THE MAIN THREAT. A STRONG COLD FRONT IS FORECAST TO DROP SOUTH ACROSS THE EASTERN PLAINS WEDNESDAY NIGHT INTO THURSDAY MORNING. STRONG NORTHERLY WINDS ARE EXPECTED BEHIND THE FRONT...WITH 30 KT GUSTS POSSIBLE OUT NEAR THE KANSAS BORDER. MODELS SLIGHTLY DIFFERENT IN PRECIPITATION CHANCES FOR THE PLAINS. FOR NOW FOLLOWED THE GFS AND ECMWF WHICH HAVE BEEN CONSISTENT. EXPECT WIDESPREAD SHOWER ACTIVITY TO SPREAD ACROSS THE EASTERN PLAINS BEHIND THE COLD FRONT WEDNESDAY NIGHT AND THURSDAY MORNING WITH MOST LOCATIONS SEEING LIGHT PRECIPITATION. THIS ACTIVITY WILL CLEAR FROM WEST TO EAST BY THURSDAY AFTERNOON WITH DRY CONDITIONS ACROSS THE REGION THURSDAY EVENING. IT SHOULD BE NOTED THAT THE NAM IS A BIT FURTHER NORTH WITH ITS STORM TRACK AND KEEPS SHOWER ACTIVITY CONFINED TO AREAS NORTH OF HIGHWAY 50. THIS WILL NEED TO BE WATCHED. THERE WILL ALSO LIKELY BE A FEW INCHES OF SNOW OVER THE HIGHER ELEVATIONS WEDNESDAY INTO THURSDAY AS SNOW LEVELS FALL TO AROUND 10 KFT. AFTERNOON TEMPERATURES WILL WARM INTO THE 70S ON WEDNESDAY...WITH 60S EXPECTED THURSDAY AFTERNOON FOR THE LOWER ELEVATIONS. OVERNIGHT LOWS WEDNESDAY AND THURSDAY MORNINGS WILL BE COOL...WITH UPPER 20S TO LOWER 30S FOR THE SAN LUIS VALLEY...AND 40S ACROSS THE EASTERN PLAINS. FRIDAY THROUGH MONDAY...THE UPPER LEVEL PATTERN WILL BECOME AMPLIFIED AND STATIONARY THROUGH THIS PERIOD...WITH AN UPPER LEVEL TROUGH OVER THE EASTERN CONUS AND UPPER RIDGE ALONG THE WEST COAST. THIS WILL PUT SOUTHERN COLORADO UNDER BROAD NORTHWESTERLY FLOW. VERY LITTLE MOISTURE WILL BE ACROSS THE AREA WITH DRY CONDITIONS EXPECTED THROUGH THE PERIOD. TEMPERATURES WILL ALSO WARM...WITH AFTERNOON HIGHS IN THE UPPER 70S TO LOWER 80S THROUGH THE WEEKEND. MOZLEY && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1031 AM MDT TUE SEP 30 2014 NO AVIATION IMPACTS EXPECTED THROUGH THE NEXT 24 HOURS AS SKIES REMAIN MOSTLY CLEAR. KALS COULD SEE SOME GUSTY SOUTHWEST WINDS THROUGH THIS AFTERNOON...BUT OTHER AREAS WILL SEE LESS WIND. && .PUB WATCHES/WARNINGS/ADVISORIES... FROST ADVISORY FROM 2 AM TO 8 AM MDT WEDNESDAY FOR COZ069>071. && $$ UPDATE...DANKERS/WFO BOULDER SHORT TERM...LW LONG TERM...MOZLEY AVIATION...DANKERS/WFO BOULDER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
405 AM MDT TUE SEP 30 2014 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 400 AM MDT TUE SEP 30 2014 DEEP UPPER AIR CYCLONE CENTERED OVER EXTREME NWRN NEBRASKA AT THIS HOUR WILL CONTINUE TO QUICKLY TRACK NORTH-NORTHEASTWARD ACRS NORTH DAKOTA THIS MORNING AND THEN UP OVER MANITOBA LATER TODAY. STRONG MID-LEVEL SUBSIDENCE ON THE BACK SIDE OF THIS DEPARTING LOW PRES SYSTEM WAS NOW OVER COLORADO. NAM AND RAP QG VERT VELOCITY FIELDS AND ON H2O VAPOR SAT IMAGERY NICELY REVEAL THIS SINKING. STABILIZATION OF THE MTN TOP LAYER PAST FEW HOURS HAS PRODUCE A STANDING MTN WAVE ALONG THE FRONT RANGE...RESULTING IN GUSTY WEST-NORTHWEST WINDS AT HIGHER ELEVATIONS OF THE FRONT RANGE. NAM AND RAP CROSS SECTIONS INDICATE CROSS BARRIER WINDS IN THE 45-55KT RANGE BY AROUND 12Z THIS MORNING...THEN ONLY SLIGHTLY WEAKER AT 15Z. WIND SENSORS ATOP THE HIGH RIDGES WERE ALREADY INDICATING GUSTS IN THE 45-55 MPH RANGE. COULD SEE SOME OF THIS MOMENTUM SPREADING TO LOWER EAST SLOPES OF THE FRONT RANGE DURING THE NEXT FEW HOURS. DO NOT SEE WINDS REACHING HIGH WIND CRITERIA AT THIS TIME. FURTHERMORE...DO NOT ANTICIPATE THESE STRONG WINDS WILL SPREAD OUT ONTO THE NEARBY THE PLAINS. ALTHOUGH THE NORTHEAST CORNER OF THE CWA COULD SEE W-NWLY WIND GUSTS TO 40 MPH LATE THIS MORNING AND EARLY THIS EVENING WITH MOMENTUM MIXING DOWN FROM ALOFT. CLEARING EARLY THIS MORNING WILL GIVE WAY TO INCREASING MID AND HIGH CLOUDS EAST OF THE MTNS LATER TODAY. CLOUDY SKIES WILL ALSO RETURN TO AREAS ALONG AND WEST OF THE CONTINENTAL DIVIDE WITH A WEATHER DISTURBANCE RACING IN FROM THE NORTHWEST. QG VV REVERSE AND GO POSITIVE THIS AFTERNOON AS THIS NEXT WAVE OF MOISTURE AND ENERGY NEARS. COULD SEE SCATTERED SHOWERS AND ISOLATED T-STORMS IN THE MTNS AND HIGH VALLEYS BY MID- TO LATE AFTERNOON. SNOW LEVEL WILL HOOVER AROUND 11 THSND FT TODAY...AND DROP TO AROUND 9500 FT THIS EVENING. HOWEVER ANY SNOW ACCUMULATION SHOULD BE MINIMAL. BY EVENING SKIES SHOULD ALSO FILL WITH CLOUDS EAST OF THE MTNS AS THIS WEAK PERTABATION PASSES BY...THEN PARTIAL CLEARING LATE WITH ITS DEPARTURE. PCPN IS NOT ANTICIPATED THRU 12Z/WED EAST OF THE MTNS. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 400 AM MDT TUE SEP 30 2014 THE NEXT UPPER LEVEL TROF WILL MOVE ACROSS COLORADO ON WEDNESDAY AFTERNOON AND NIGHT. AN ASSOCIATED COLD FRONT WILL MOVE ACROSS NORTHEAST COLORADO DURING THE AFTERNOON HOURS WITH INCREASING NORTHERLY FLOW AT LOW LEVELS. QG FIELDS SHOWING INCREASING ASCENT DURING THE DAY WEDNESDAY...PEAKING OVER THE FRONT RANGE IN THE AFTERNOON AND FURTHER EAST ON THE PLAINS DURING THE EARLY EVENING. SHORT RANGE MODELS ARE FAIRLY CONSISTENT ON TIMING WITH THIS TROF. GIVEN THE FRONT AND FORCING ALOFT WILL BUMP POPS UP FURTHER TO LIKELY OVER MOST SECTIONS DURING WEDNESDAY AFTERNOON AND EVENING. THE TROF IS QUITE PROGRESSIVE SO SHOWERS WILL END FROM NORTHWEST TO SOUTHEAST WEDNESDAY NIGHT AS PRECIP DURATION WILL BE IN THE 3-6 HOUR RANGE. THE AIRMASS WILL BE COLD ENOUGH TO SUPPORT SOME SNOW ACCUMULATION IN THE MOUNTAINS. FOR THURSDAY AND BEYOND...THERE WILL BE A DRYING AND WARMING TREND AS COLORADO WILL BE UNDER A MODERATE...NORTHWEST FLOW PATTERN. && .AVIATION...(FOR THE TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 400 AM MDT TUE SEP 30 2014 VFR CONDITIONS WILL PREVAIL AT DENVER AREA TERMINAL AND GATES THROUGH 12Z/WED. ALTHOUGH CEILINGS MAY LOWER BELOW 10 THSND FT AGL AFTER 22Z TODAY AND POSSIBLY LOWER TO AROUND 8 THSND FT AGL EARLY THIS EVENING AS A WEAK UPPER AIR DISTURBANCE PASSES BY. AT THIS TIME...DO NOT ANTICIPATE ANY PCPN WITH THIS SYSTEM. EXPECT DRAINAGE WINDS OF 5-12KTS AT DIA AND APA THROUGH MID- MORNING...THEN A GRADUAL CLOCKWISE SHIFT TO WLY WINDS OF 7-14KTS BY MIDDAY WHERE THEY SHOULD REMAIN THROUGH EARLY THIS EVENING BEFORE RESUMING A TYPICAL DRAINAGE PATTERN. ON THE OTHER HAND ...WEST-SOUTHWEST WINDS OF 10-25KT CAN BE EXPECTED AT BJC NEAR THE FOOTHILLS THROUGH MIDDAY...THEN 7-13 NWLY WINDS IN THE AFTERNOON...AND THEN S-SWLY WINDS OF 4-8KTS OVERNIGHT. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BAKER LONG TERM...ENTREKIN AVIATION...BAKER
AREA FORECAST DISCUSSION
NWS ALBANY NY
ISSUED BY NATIONAL WEATHER SERVICE BURLINGTON VT 211 PM EDT TUE SEP 30 2014 .SYNOPSIS... A PASSING UPPER LEVEL LOW WILL ALLOW FOR ISOLATED TO SCATTERED SHOWERS TODAY INTO TOMORROW. TEMPERATURES WILL REMAIN SLIGHTLY ABOVE NORMAL THROUGH THE REMAINDER OF THE WORK WEEK...BEFORE A COLD FRONT BRINGS MORE WIDESPREAD SHOWERS AND COOLER TEMPERATURES FOR THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 150 PM EDT...EARLY AFTERNOON UPDATE DOESN`T FEATURE MUCH IN THE WAY OF ANY SIGNIFICANT FORECAST CHANGE FOR THE REST OF THE AFTERNOON INTO EARLY EVENING. JUST BATTLING THE PLACEMENT OF THE LOWER CLOUDS THANKS TO THE BACKDOOR FRONT WHICH IS WASHING OUT OVER THE AREA. CLOUDS ARE STARTING TO ERODE, ALBEIT SLOWLY. WHERE THE SUN HAS BEEN OUT, TEMPERATURES ARE ALREADY AROUND 70F. MADE SOME ADJUSTMENTS TO THE AFTERNOON HIGHS -- BASICALLY A SLIGHT LOWERING IN THE CLOUDY AREAS (PITTSFIELD & GLENS FALLS -- I`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`D0` PER THE DROUGHT MONITOR /ABNORMALLY DRY/. WE WILL HAVE THE HIGHEST POPS FOR THE OVERNIGHT PERIOD FRIDAY INTO EARLY SATURDAY MORNING. FROPA IS EXPECTED DURING SATURDAY MORNING WITH BRISK AND COOLER CONDITIONS EXPECTED FOR THE WEEKEND. IN FACT...THE DEGREE OF COLDER AIR ADVECTING IN WILL ACTIVATE LAKE ONTARIO CLOUDS AND SHOWERS. PER TRAJECTORIES...THE BEST POTENTIAL FOR LAKE EFFECT SHOWERS WILL BE ACROSS THE DACKS. THIS UPPER TROUGH WILL REMAIN BROAD ACROSS THE GREAT LAKES REGION EXTENDING INTO EARLY NEXT WEEK WHICH WILL KEEP OUR PATTERN COOL AND UNSETTLED. OVERALL TEMPERATURES WILL AVERAGE NEAR TO BELOW NORMAL WITH PRECIPITATION NEAR TO ABOVE NORMAL. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THROUGH 18Z WEDNESDAY...COMBINATION OF VFR AND MVFR CONDITIONS (DUE TO THE LOW CLOUDS/CEILINGS). SOME IMPROVEMENT EXPECTED THE NEXT FEW HOURS, BUT WITH SUNSET EXPECT THE LOWER CLOUDS ACROSS SOUTHERN NEW ENGLAND TO BEGIN TO EXPAND WESTWARD AND FILLING IN THROUGH THE HUDSON RIVER VALLEY. ANTICIPATE MVFR, IF NOT IFR, CEILINGS TO BE COMMON AFTER 06Z. MAY EVEN AGAIN SEE FOG DEVELOPING SIMILAR TO LAST NIGHT. EXPECTING A FEW SHOWERS TO DEVELOP AROUND POU. AT THIS POINT JUST MENTIONED VCSH SINCE TIMING IS UNCERTAIN. THESE SHOWERS WILL BE AROUND INTO MUCH OF WEDNESDAY AS WELL. COULD SEE PRECIPITATION AS FAR NORTH AS ALB AND PSF, BUT KEPT THE MENTION OF SHOWERS OUT AT THIS TIME SINCE THE CHANCES ARE LOW. SURFACE WINDS WILL BE ON THE LIGHT SIDE. AGAIN, THE IFR CONDITIONS WILL ONLY SLOWLY IMPROVE TO MVFR AFTER 14/15Z WEDNESDAY. OUTLOOK 18Z WEDNESDAY THROUGH SUNDAY.. 18Z WED TO 00Z FRI...MVFR TO LOCAL IFR WITH SCATTERED SHOWERS 00Z FRI TO 12Z SAT...PRIMARILY VFR 12Z SAT ONWARD...MVFR WITH SHOWERS. STRONG/GUSTY SURFACE WINDS AND LLWS ALSO POSSIBLE, ESPECIALLY SATURDAY. && .HYDROLOGY... NO HYDROLOGIC RELATED ISSUES ARE EXPECTED THROUGH THIS WEEK. ANY SHOWERS OVERNIGHT AND WEDNESDAY WILL NOT PRODUCE SIGNIFICANT RAINFALL AMOUNTS. ADDITIONAL RAINFALL IS EXPECTED SATURDAY. THOUGH RAINFALL TOTALS WILL BE HEAVIER -- PERHAPS 3/4" OR SO --- NO SIGNIFICANT RESPONSES ARE EXPECTED AT THIS POINT ON AREA RIVERS. 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...FRUGIS NEAR TERM...NASH SHORT TERM...FRUGIS LONG TERM...BGM AVIATION...NASH HYDROLOGY...NASH
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
938 PM EDT WED OCT 1 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO WORK IN FROM THE NORTH TONIGHT BEFORE SLIDING TO OUR EAST BY FRIDAY. A VERY POTENT COLD FRONT SWEEPS THROUGH FRIDAY NIGHT INTO SATURDAY MORNING FOLLOWED BY ANOTHER BRIEF RESPITE OF HIGH PRESSURE THROUGH MONDAY. THEN A SERIES OF IMPULSES LOOK TO AFFECT THE REGION THROUGH AT LEAST MID-WEEK. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... NO MAJOR CHANGES TO THE FORECAST THIS EVENING. AN AREA OF LOW PRESSURE ALOFT CONTINUES TO SPIN TO OUR NORTHEAST AND WILL SLOWLY DRIFT INTO NY AND NEW ENGLAND COASTAL WATERS TONIGHT. AN ABUNDANCE OF LOW LEVEL MOISTURE WILL CONTINUE TO ADVECT INTO THE AREA AROUND THE LOW, WHICH WILL KEEP MOSTLY CLOUDY TO OVERCAST SKIES WITH A SLIGHT CHANCE OF LIGHT RAIN/SPRINKLES OR DRIZZLE FOR THE EARLY PART OF TONIGHT. THE LATEST GFS AND NAM KEEP THE MAJORITY OF BARELY MEASURABLE PRECIP ACROSS OUR NORTHEASTERN AND COASTAL AREAS FOR THE EARLY PART OF THE NIGHT WHILE THE HRRR DISSIPATES MOST ACTIVITY THROUGH THE NIGHT BEFORE IT GETS HERE. SO WE WILL KEEP THE HIGHEST POPS ACROSS THE COASTAL AREAS WHERE THERE ARE CURRENTLY REFLECTIVITIES AND THE NORTHEASTERN AREAS WHERE SOME LIGHT PRECIP MAY MOVE IN LATER. MOST OF OUR CWA WE ARE EXPECTING TO BECOME MOSTLY CLOUDY (OR STAY CLOUDY) AS THE FCST SOUNDINGS ARE PRETTY MOIST BELOW 850MB. TO BE CONSISTENT, THIS WOULD PRECLUDE MUCH MENTION OF PATCHY FOG AND ALSO CONTINUING TO SIDE WITH THE HIGHER STAT GUIDANCE FOR MIN TEMPS. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/... GOING WITH A QUICKER MODELING TREND TO ENDING THE PCPN CHANCES BASED ON THE FASTER 500MB LOW MOVEMENT. PCPN CHANCES IN MORNING ONLY. MODELS INDICATING CONVECTIVE TEMPERATURE BEING REACHED AND MORE LOW LEVEL MOISTURE THAN EVEN TODAY. WE ARE NOT GOING TO BE FAST TO INCREASE SUNSHINE BECAUSE OF THIS. ON THE OTHER HAND ANY CHANNELIZED PVA IS DONE BY THE MIDDLE OF THE AFTERNOON. FULL SUN MACROS SUGGESTING MAX TEMPS ABOUT 5F ABOVE STAT GUIDANCE. THAT STAT GUIDANCE DROP OFF LOOKS REASONABLE GIVEN AFTN PREDICTED CONVECTIVE TEMPS ARE AROUND 70. AN INDICATOR OF POSSIBLY FASTER CLEARING TOMORROW WOULD BE IF WINDS BACK FURTHER TOWARD THE NORTHWEST THAN PREDICTED. && .LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/... OPERATIONAL MODELS ARE IN PRETTY GOOD AGREEMENT WITH THE LARGE SCALE FEATURES THROUGH THE WEEKEND. THE POTENTIAL FOR PHASING OF A STRONG NORTHERN AND SOUTHERN STREAM SYSTEM TO OUR WEST THAT CARVES OUT A VERY LARGE AND DEEP CLOSED LOW/TROUGH ACROSS THE UPPER MID-WEST BY LATE FRIDAY NIGHT WILL BE THE MAIN DRIVER FOR A MAJORITY OF THE LONG TERM PERIOD. A FEW BREAKS IN THE ACTION ARE EXPECTED WITH WEAK RIDGING, BUT OVERALL WE WILL REMAIN UNSETTLED THROUGH MID NEXT WEEK. FRIDAY...GUIDANCE HAS BEEN RUNNING A BIT SLOWER WITH BREAKING THE MID-LEVEL RIDGING DOWN AND THEREFORE KEEPS US MOSTLY DRY DURING THE DAYTIME HOURS. EASTERLY FLOW WILL KEEP US DAMP WITH LOTS OF CLOUD COVER IN PLACE. TEMPERATURES CLIMB INTO THE LOW-70S. STRONG COLD FRONT NEARS FROM THE WEST LATE FRIDAY NIGHT WITH SHOWERS BEGINNING TO OVERSPREAD. THE LACK OF INSTABILITY, WITH ITS NOCTURNAL PASSAGE, SHOULD LIMIT THE AMOUNT OF THUNDER, IF ANY, THOUGH THERE IS AMPLE LIFT WITH THIS SYSTEM TO POSSIBLY SEE A FEW TALLER UPDRAFTS. SATURDAY...THE FRONT CONTINUES TO BARREL THROUGH THE REGION EARLY. PRETTY HEFTY HEIGHTS FALLS WITH VERY ROBUST UPPER LEVEL DYNAMICS, 500MB JET NEARLY 70KTS, AND A NEGATIVELY TILTING TROUGH AXIS ARE PRIME INGREDIENTS FOR HEAVY RAINFALL...POSSIBLY EVEN A NARROW COLD FRONTAL RAIN BAND. TOO EARLY TO HAVE HIGHER CONFIDENCE ON THE NARROW RAIN BAND BUT THE MODELS ARE INDICATING A SHARP WIND SHIFT WITH THE STRONG FRONTAL CONVERGENCE ZONE LIFTING, LOW EQUILIBRIUM LEVELS, AND TREMENDOUS UPPER LEVEL MOMENTUM...EVEN WITH THE LACK OF SURFACE INSTABILITY. EITHER WAY THESE SHOWERS WILL BE SOAKERS AS WE TAP INTO THE GOMEX/ATLANTIC MOISTURE STREAMING FROM THE SOUTH AND EAST. ANTECEDENT CONDITIONS ARE STILL PRETTY DRY ACROSS THE REGION SO NOT EXPECTING ANYTHING OUT OF THE ORDINARY TO OCCUR WITH THE POSSIBLE HEAVIER RAIN. POST FRONTAL WINDS LOOK TO BE STRONG AS WELL WITH A DECENT ISALLOBARIC COMPONENT AND STRONG COLD AIR ADVECTION. TEMPERATURES SHOULD BE DROPPING THROUGHOUT THE DAY SO WE COULD BE LOOKING AT A LATE MORNING HIGH. SUNDAY...COLD FRONT OFF TO THE EAST WITH TROUGHING ESTABLISHING ITSELF TO OUR WEST AND A CRISP COOL AIRMASS IN PLACE. A DRY DAY IS ON TAP WITH TEMPERATURES IN THE UPPER-50S TO LOW-60S. MONDAY - WEDNESDAY...A SERIES OF UPPER LEVEL WAVES ROTATE THROUGH THE BASE OF THE TROUGH TO OUR WEST. THIS ALLOWS FOR CHANCES OF SHOWERS EACH DAY THOUGH TIMING OF THE WAVES IS NEARLY IMPOSSIBLE AT THIS JUNCTURE. TEMPERATURES SHOULD CLIMB BACK TOWARDS NORMAL. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. CONDITIONS VARY FROM SITE TO SITE, FROM VFR TO MVFR. THERE IS AN ABUNDANCE OF LOW LEVEL MOISTURE ASSOCIATED WITH THE LOW PRESSURE ALOFT LOCATED TO OUR NORTHEAST. THIS WILL KEEP THE CHANCE FOR OCCASIONAL MVFR CIGS FOR A FEW MORE HOURS, BEFORE WE EXPECT ALL SITES TO LOWER TO MVFR OVERNIGHT. WINDS SHOULD BE NORTHEAST AT 5 TO 10 KNOTS. ON THURSDAY WE EXPECT AN IMPROVEMENT TO VFR BY LATE MORNING/EARLY AFTERNOON, SIMILAR TO WEDNESDAY. WINDS SHOULD BE MOSTLY NORTH TO NORTHEAST WITH SPEEDS OF AROUND 10 KNOTS. OUTLOOK... FRIDAY...MOSTLY VFR. RAIN, HEAVY AT TIMES LATE, OVERSPREADS THE AREA FROM THE WEST. REDUCED VSBYS AND CIGS IN HEAVY SHOWERS. EASTERLY WINDS BACK SOUTHEAST. SATURDAY...MVFR/IFR EARLY IN HEAVY RAIN, TRENDING VFR. WINDS CONTINUE TO BACK TO THE WEST-NORTHWEST BECOMING GUSTY. SUNDAY...VFR. && .MARINE... SEAS AT BUOY9 ARE AROUND 4 TO 5 FEET, ABOUT A FOOT OVER WAVE WATCH GUIDANCE. UNFORTUNATELY BUOY65 REMAINS OTS. WAVE WATCH GUIDANCE CONTINUES TO BE QUITE ROBUST WITH THE SWELLS AND EVEN IF THIS GFS BASED RUN IS TOO SLOW, SEAS SHOULD REMAIN AT OR ABOVE SMALL CRAFT ADVISORY CRITERIA INTO THURSDAY. NOT AS CONFIDENT ABOUT THE WINDS GETTING THERE AS THE JET MAY PASS EAST OF OUR COASTAL WATERS. BECAUSE OF THE LATTER, NO SMALL CRAFT ADVISORIES WILL BE ISSUED FOR DELAWARE BAY. OUTLOOK... FRIDAY...SCA CONDITIONS WILL LIKELY PERSIST ON OUR WATERS THROUGH EARLY FRIDAY AS WE CONTINUE WITH THE EASTERLY ONSHORE FLOW. SEAS WILL CONTINUE TO RUN AROUND 5 FEET. WINDS BEGIN TO BACK TOWARDS THE SOUTH-SOUTHEAST BY LATE FRIDAY AHEAD OF THE NEXT COLD FRONT. SATURDAY...STRONG COLD FRONT MOVES THROUGH. WINDS BACK TOWARDS THE WEST-NORTHWEST LATER IN THE DAY AND WITH STRONGER COLD AIR ADVECTION OCCURRING, WE COULD SEE A RETURN TO SCA CONDITIONS. GUSTY WINDS IN THE HEAVIER RAIN SHOWERS...MOSTLY IN THE MORNING. SUNDAY...RESIDUAL SCA WIND GUSTS DROP OFF BY LATE MORNING. SEAS SHOULD ALSO DROP BELOW SCA CONDITIONS TO AROUND 3-4 FEET. && .TIDES/COASTAL FLOODING... WITH PERSISTENT BREEZY NORTHERLY AND NORTH NORTHEASTERLY WINDS TONIGHT INTO TOMORROW, TIDAL DEPARTURES BY TOMORROW AFTERNOONS HIGH TIDE SHOULD RANGE FROM 0.5 TO 1 FT ABOVE ASTRONOMICAL TIDE. THIS SHOULD RESULT IN TIDES BELOW MINOR FLOODING THRESHOLDS. HOWEVER, WE WILL CONTINUE TO MONITOR THE DEPARTURES OVER THE NEXT HIGH AND LOW TIDE CYCLES. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT FRIDAY FOR ANZ450>455. && $$ SYNOPSIS...HEAVENER NEAR TERM...GIGI/ROBERTSON SHORT TERM...GIGI LONG TERM...HEAVENER AVIATION...GIGI/HEAVENER/ROBERTSON MARINE...GIGI/HEAVENER TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS MOUNT HOLLY NJ
1244 PM EDT TUE SEP 30 2014 .SYNOPSIS... A LOW PRESSURE SYSTEM AND WEAK FRONT WILL AFFECT THE WEATHER TODAY AND TONIGHT. HIGH PRESSURE WILL BUILD IN WEDNESDAY AND REMAIN THROUGH FRIDAY. A STRONG COLD FRONT WILL CROSS THE REGION FRIDAY NIGHT INTO EARLY SATURDAY. HIGH PRESSURE WILL BUILD ACROSS THE AREA SATURDAY NIGHT INTO EARLY MONDAY. LOW PRESSURE WILL APPROACH FOR LATER MONDAY AND INTO NEXT TUESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH THE MIDDAY UPDATE, WE ADJUSTED SKY COVER ACROSS THE REGION TO REFLECT THE CLEARING SEEN ACROSS A GOOD PORTION OF THE AREA. SOME SCATTERED CUMULUS IS BEGINNING TO DEVELOP, THOUGH, AS CONVECTIVE TEMPS ARE BEING MET, AND THIS WILL INCREASE SOME THROUGH THE AFTERNOON. OTHERWISE WITH REGARDS TO ANY POSSIBLE ISOLATED TO SCATTERED LATE-DAY SHOWER ACTIVITY, WE TRIMMED IT BACK SOME THROUGH THE LATE AFTERNOON TO EVENING, BASED ON HRRR GUIDANCE. HIGHEST CHANCE POPS ARE STILL CONFINED TO THE NORTHWEST PART OF THE FORECAST AREA. HOURLY TEMPS AND DEWPOINTS WERE TWEAKED USING THE LAV/LAMP GUIDANCE, AND WE NUDGED MAX TEMPERATURES UP A DEGREE OR TWO IN A FEW SPOTS. REST OF TODAY...BETWEEN SHORT WAVES IT SHOULD BE QUIET THROUGH EARLY AFTERNOON WITH SOME SUNSHINE VSBY AT TIMES THROUGH THE SCATTERED CLOUDS. AFTERNOON HEATING DEVELOPS SMALL SHOWERS NW OF I95 WHICH PROBABLY HAVE A TENDENCY TO DRIFT WEST. IF THERE IS TO BE ANY THUNDER THIS FAR EAST...IT SHOULD BE CONFINED TO THE FAR WESTERN EDGE OF OUR FCST AREA WESTERN BERKS INTO THE POCONOS. OVERALL: TEMPS ABOUT 7F WARMER THAN NORMAL AND THE ENTIRE MONTH OF SEPTEMBER SHOULD AVERAGE ABOUT 1.5 DEGREES ABOVE NORMAL MOST AREAS. FCST WAS BASED ON A 50 50 BLEND OF THE 00Z/30 GFS/NAM MOS GUIDANCE. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM WEDNESDAY/... TONIGHT...COOL POOL ALOFT SLIDES EASTWARD ACROSS THE REGION WITH 500MB TEMPS NEAR -15-16C. BANDS OF SHOWERS MAY BE OCCURRING WITH SUBTLE LIFT FROM BOTH WEAK BUT DEEP ELY MOIST WINDS NORTH OF I78 AND THE BACKDOOR COOL FRONT CONVERGENCE ZONE DRIVEN BY THE STRENGTHENING NE FLOW NE OF THE BACKDOOR CF. ADDITIONALLY FOG IS LIKELY TO DEVELOP IN THE COOLER BL AIR NE OF THE FRONTAL BOUNDARY. TEMPS ABOUT 10F WARMER THAN NORMAL. FCST WAS BASED ON A 50 50 BLEND OF THE 00Z/30 GFS/NAM MOS GUIDANCE. && .LONG TERM /WEDNESDAY THROUGH MONDAY/... THE LAST OF THE UPPER LOW AND WEAK SFC LOW WILL BE EXITING THE AREA WEDNESDAY. THERE WILL STILL BE ENOUGH RESIDUAL LOW LEVEL MOISTURE TO PRODUCE SOME SCT SHOWERS...MOSTLY DURING THE FIRST PART OF THE DAY. WE HAVE RETAINED THE CHC POPS FROM EARLIER. THE POPS DECREASE DURING THE AFTERNOON FROM W TO E. TEMPERATURES WED NEAR OR A BIT ABOVE NORMAL...MOSTLY LOW/MID 70S. WED NIGHT THRU FRI MORNING...MOSTLY DRY WEATHER DURING THIS PERIOD AS HIGH PRESSURE BUILDS ACROSS THE AREA. PARTLY TO MOSTLY SUNNY DAYTIME PERIODS AND MOSTLY CLR OVERNIGHTS. TEMPERATURES AGAIN...NEAR OR A BIT ABOVE NORMAL. FRI AFTERNOON THRU SATURDAY...A STRONG COLD FRONT WILL CROSS THE AREA FRI NIGHT INTO EARLY SAT. THE MODELS HAVE BEEN RATHER CONSISTENT WITH A 6 HR OR SO WINDOW OF QPF CENTERED AROUND FRI EVENING. WE HAVE UPPER THE POPS TO LIKELY FOR THE EVENING PERIOD WITH THE EXTRA CONFID IN MULTIPLE/CONSISTENT TRENDS. PROBABILITIES FOR THUNDER LOOK LOW AT THIS POINT SO WE WILL HOLD ON THAT...SOME GUSTY WINDS WILL ACCOMPANY THE FROPA HOWEVER. TEMPS WILL DROP BACK TO BELOW NORMAL SAT WITH DECENT COLD ADVECTION EXPECTED AFTER FROPA. SAT NIGHT THRU MONDAY...ANOTHER DRY PERIOD EXPECTED WITH HIGH PRESSURE BUILDING IN, TEMPERATURES WILL BE BELOW NORMAL SUNDAY...BUT BACK TO NEAR NORMAL MONDAY. LOWS BOTH SAT AND SUN NIGHTS WILL FEATURE LOW 40S NORTH RANGING TO THE LOW 50S OVER THE DELMARVA AND METRO PHILADELPHIA. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. REST OF TODAY...MOSTLY SCT- BKN CLOUDS AOA 4000 TO 5000 FT FOR ALL SITES WITH A POSSIBLE SHOWER VCNTY KRDG/KABE LATE IN THE DAY. LIGHT SOUTH WIND TURNING E, REMAINING UNDER 10 KNOTS. TONIGHT...WIND BECOMING NE AT 5-15 KT AND A DECK OF IFR ST/FOG SHOULD DEVELOP SOUTHWESTWARD FROM LONG ISLAND BEHIND THE BACKDOOR COLD FRONT CURRENTLY MOVING SW FROM SOUTHERN NEW ENGLAND. CHANCE OF SHOWERS...MAINLY N OF KPHL. OUTLOOK... WEDNESDAY...MOSTLY VFR. SCT SHOWERS WITH SHORT PERIODS OF MVFR CONDITIONS POSSIBLE. E/NE WINDS WITH GUSTS UP TO 15 KNOTS. THURSDAY...MORNING FOG WITH LOCAL LOWER CIGS/VSBYS...THEN MOSTLY VFR. N WIND GUST 15 KT...BECOMING NE LATE. FRIDAY...VFR CIGS EXCEPT POSSIBLE MVFR CONDITIONS IN ST/FOG EARLY FRIDAY MORNING AND THEN AGAIN FRIDAY NIGHT IN SHOWERS NEAR A COLD FRONT. E-SE WIND BECOMING S OR SW LATE AT NIGHT. SATURDAY...A FEW MORNING SHOWERS EAST...THEN VFR CONDITIONS EXPECTED. && .MARINE... NO HEADLINES ATTM. TODAY...LIGHT WINDS AND SEAS AOB 3 FT TODAY WITH THE S-SW WIND TURNING TO THE EAST OR NORTHEAST. TONIGHT...NE WINDS INCREASING WITH GUSTS TO 22 KT LATE AND SEAS BUILDING TO NEAR 4 FT BY SUNRISE WEDNESDAY. CAPPED SEAS AT 4 FT THROUGH 8AM WEDNESDAY AS I BELIEVE THE GFS WW3 GUIDANCE IS TOO SOON TOO HIGH. OUTLOOK... WEDNESDAY THRU WED NIGHT: NE FLOW WITH BUILDING WINDS AND SEAS AND SCA CRITERIA EXPECTED ALONG THE NNJ COAST AND THEN POSSIBLY SOUTHWARD TO THE ENTIRE ATLANTIC COAST LATER WEDNESDAY OR WEDNESDAY NIGHT. DELAWARE BAY MAY NOT SEE WIND GUSTS ABOVE 22 KT WITH ANY SCA HEADLINE THERE NOT LIKELY. HAVE HELD OFF ON ISSUING ANY FORMAL HEADLINES ON THIS FORECAST UPDATE AS CONDITIONS WILL JUST MEET LOWER END SCA CRITERIA AND CONFIDENCE IS NOT YET HIGH. THURSDAY...SMALL CHANCE OF A CONTINUING SCA FLAG SEAS ON THE ATLANTIC WATERS FROM NE SWELLS GENERATED BY AN OFFSHORE LOW. CONDITIONS MAY DROP BELOW SCA CRITERIA LATE. FRIDAY...SOUTH WINDS INCREASING AND BUILDING SEAS. SCA CONDITIONS A GOOD BET BY AFTERNOON. SHOWERS WITH GUSTY WINDS LATE. SATURDAY...SCA CONDITIONS EARLY WITH SCT SHOWERS...THEN WINDS AND SEAS DIMINISHING LATE. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...NONE. NJ...NONE. DE...NONE. MD...NONE. MARINE...NONE. && $$ SYNOPSIS...O`HARA NEAR TERM...DRAG/KLINE SHORT TERM...DRAG LONG TERM...O`HARA AVIATION...DRAG/KLINE/O`HARA MARINE...DRAG/O`HARA
AREA FORECAST DISCUSSION
NWS MIAMI FL
916 PM EDT WED OCT 1 2014 .UPDATE... RADAR SHOWING CONVECTION HAS CONTINUED LATER INTO THE EVENING HOURS THAN PREVIOUSLY THOUGH. MUCH OF THE STRONGER CONVECTION LOOKS TO BE RUNNING ALONG A FRONTAL BOUNDARY THAT HAS DRIFTED A LITTLE SOUTH, AND IS SITTING JUST TO THE NORTH OF JUPITER. SO, HAVE BUMPED UP POPS FOR THE NEXT SEVERAL HOURS, AND ADDED SOME THUNDERSTORMS TO THE WEATHER THIS EVENING FOR THE ATLANTIC WATERS, AND PALM BEACH COAST. THE HRRR DOES CONTINUE TO INDICATE THIS SHOULD COME TO AN END OVER THE NEXT HOUR OR TWO. && .PREV DISCUSSION... /ISSUED 755 PM EDT WED OCT 1 2014/ AVIATION... THUNDERSTORMS ARE BECOMING ENHANCED ACROSS THE ATLANTIC WATERS ATTM SO KEPT VCTS THROUGH 02Z FOR ALL EAST COAST TERMINALS EXCEPT KPBI. ADDITIONAL SHOWERS ARE SEEN JUST WEST OF THE EAST COAST SITES AND MAY BRIEFLY AFFECT THE TERMINALS BUT SHOULD REMAIN ISOLATED. WINDS SHOULD BE LIGHT AND VARIABLE OVERNIGHT BEFORE BECOMING NORTHWESTERLY DURING THE LATE MORNING HOURS TOMORROW. GUIDANCE IS HINTING AT AN EAST COAST SEA BREEZE DEVELOPING AND PUSHING INTO THE TERMINALS SO PREVAILED A GENERAL EASTERLY WIND AT ALL EAST COAST SITES EXCEPT KTMB WHICH MAY BE JUST TOO FAR INLAND TO SEE AN EASTERLY WIND. PREV DISCUSSION... /ISSUED 349 PM EDT WED OCT 1 2014/ SHORT TERM...(TONIGHT-FRIDAY NIGHT) THE LATEST SHORT-RANGE MODEL GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES THE MOIST WESTERLY FLOW ACROSS THE AREA SOUTH A STALLED FRONTAL BOUNDARY CONTINUING THROUGH THE MAJORITY OF THE PERIOD. WESTERLY LOW-LEVEL FLOW UP TO 10 KFT COMBINED WITH THE EAST COAST SEA BREEZE WILL FOCUS THE BULK OF THIS ACTIVITY ACROSS THE CENTRAL AND EASTERN PORTIONS OF THE AREA EACH DAY...ESPECIALLY AS THE DEEP WESTERLY FLOW WEAKENS. MODEL PWAT GRADIENTS REFLECT THIS POTENTIAL AND INDICATE VALUES RANGING FROM 1.62" ALONG THE GULF COAST UP TO AROUND 2" ALONG THE EAST COAST THROUGH THE AFTERNOON/EVENING PERIODS THURSDAY AND FRIDAY. ALTHOUGH THE SEVERE THUNDERSTORM THREAT WILL REMAIN LOW THROUGH THIS TIME...PERIODS OF HEAVY RAINFALL COULD RESULT IN LOCALIZED FLOODING ACROSS THE EAST COAST AREAS. /AG LONG TERM (SATURDAY-WEDNESDAY)... A SIGNIFICANT CHANGE IN THE WEATHER IS LOOKING MORE LIKELY FOR THE LATER PART OF THE WEEKEND AS NOW BOTH GFS AND ECMWF ARE SENDING THE FIRST COLD FRONT OF THIS FALL SEASON ACROSS SOUTH FL SATURDAY NIGHT AND OFF OUR COAST SUNDAY MORNING. GFS ENSEMBLES ARE SUPPORTING THIS FROPA IDEA AS WELL...WITH THE AVERAGE OF THE MEMBERS A DEGREE OR TWO BELOW THE OPERATIONAL GFS MOS SUNDAY AND SUNDAY NIGHT. GIVEN THIS...HAVE TRENDED THE FORECAST COOLER SUNDAY THROUGH TUESDAY. THIS WOULD BE A VERY NOTICEABLE CHANGE FROM THE SULTRY HIGH DEWPOINTS WE`VE FELT SINCE MAY...WELL INTO THE 70S. BEHIND THE FRONT, DEWPOINTS WILL FALL INTO THE 60S ON A NICE NORTHERLY BREEZE. HIGHS ON SUNDAY ARE FORECAST TO BE ONLY IN THE LOWER-MID 80S. LOWS ARE FORECAST TO DROP INTO THE 60S INTERIOR AND GULF COAST BOTH SAT AND SUN NIGHT...AND LOWER 70S EAST COAST METRO WITH COMFORTABLE HUMIDITY...LETTING US KNOW THAT IT IS INDEED FALL. THIS IS PRETTY EARLY IN THE SEASON FOR A COLD FRONT, BUT THE PATTERN OF AN AMPLIFIED TROUGH ACROSS THE EASTERN CONUS DOES NOT SEEM TO WANT TO LET GO AS THE TROUGH CONTINUES RE-ESTABLISHING ITSELF EVEN AFTER TEMPORARY FLOW CHANGES. GIVEN THIS, AN EARLY SEASON COLD FRONT ISN`T SHOCKING...AND IN FACT THE LONGER RANGE GFS SHOWS ANOTHER COLD FRONT AS WE ENTER MID OCTOBER. COULD THIS BE THE BEGINNING OF A PARADE OF COLD FRONTS? TOO EARLY TO SAY, BUT I`M INCLINED TO BELIEVE SO GIVEN THE AFOREMENTIONED LOCKED SYNOPTIC PATTERN. /GREGORIA MARINE... A FRONTAL BOUNDARY WILL STALL ACROSS THE STATE THROUGH FRIDAY WITH LIGHT WINDS AND LOW SEAS CONTINUING. THE FIRST STRONG COLD FRONT OF THE FALL SEASON IS FORECAST TO SWEEP ACROSS THE LOCAL WATERS SATURDAY NIGHT WITH HIGH PRESSURE BUILDING FROM THE NORTH IN ITS WAKE ON SUNDAY. SEAS WILL INCREASE BEHIND THE COLD FRONT FROM THE NORTH, ESPECIALLY OFF THE PALM BEACH COAST. /AG && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 76 88 76 86 / 30 30 20 50 FORT LAUDERDALE 77 88 77 87 / 20 50 20 50 MIAMI 77 89 76 87 / 20 60 20 50 NAPLES 78 86 76 86 / 20 20 0 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...13/SI LONG TERM....57/DG
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
825 PM EDT WED OCT 1 2014 .UPDATE (REST OF TONIGHT AND THURSDAY)... 00Z WATER VAPOR AND H4 RAP ANALYSIS SHOWS THE NORTHERN STREAM FLOW CARVING OUT A DEEP LONGWAVE TROUGH ACROSS THE WESTERN HALF OF THE CONUS/UPPER MIDWEST BEFORE THE FLOW RIDGES WELL NORTHWARD INTO CENTRAL/EASTERN CANADA. SOUTH OF THIS MAIN FLOW WE FIND AN UPPER LOW MIGRATING OFF THE NEW ENGLAND COAST WITH MORE ZONAL FLOW FURTHER SOUTH THROUGH THE DEEP SOUTH. UPPER LEVELS PER WV IMAGERY ARE ON THE DRY SIDE OVER THE FL PENINSULA THIS EVENING. THE MORNING KTBW SOUNDING PROFILE SAMPLED THIS DRY LAYER ABOVE 500MB VERY WELL AND THE 00Z EVENING SOUNDING SHOWS THE DEPTH OF THE DRIER AIR INCREASED DURING THE DAY AND WAS PART OF THE REASON WEDNESDAY SAW SIGNIFICANTLY LESS RAINFALL COVERAGE THAN PREVIOUS DAYS. AT THE SURFACE...A WEAK SURFACE TROUGH EXTENDS ACROSS THE CENTRAL PENINSULA WITH HIGH PRESSURE TO THE NORTH RIDGING INTO THE NORTHERN PART OF THE STATE. AS OF 00Z...STILL SEEING A FEW SCATTERED SHOWERS TO THE NORTH OF THE I-4 CORRIDOR...BUT THIS ACTIVITY WILL BE DISSIPATING DURING THE NEXT COUPLE OF HOURS WITH THE LOSS OF DIURNAL HEATING. AFTER THESE STORMS ARE GONE...WILL ANTICIPATE A DRY AND SEASONABLE OVERNIGHT PERIOD. THURSDAY WILL SIMILAR DAY WITH LESS CONVECTIVE COVERAGE THAN WAS SEEN OVER THE PAST WEEKEND. GRADIENT WILL BE WEAK ALLOWING SEA-BREEZE DEVELOPMENT ON BOTH COASTS. THIS SETUP SUGGESTS THE BEST SHOWER COVERAGE ON THURSDAY WILL BE INLAND FROM I-75...AND MAINLY AFTER 2-3PM. && .AVIATION... THE LAST OF THE AFTERNOON SCT SHOWERS ARE DIMINISHING WITH THE SETTING SUN THIS EVENING AND ANTICIPATE A GENERAL DRY OVERNIGHT WITH PREVAILING VFR CONDITIONS FOR THE NEXT SEVERAL HOURS. LATE AT NIGHT WILL NEED TO WATCH THE POTENTIAL FOR PATCHY LOWER CLOUDS THAT COULD BRIEFLY DROP KTPA/KPIE/KLAL DOWN TO MVFR LEVELS. CONFIDENCE IN THIS MVFR OCCURRENCE IS NOT HIGH...AND HAVE LEFT MENTION OUT FOR THE CURRENT TAF PACKAGE. ANY LOWER CLOUDS WILL BURN OFF EARLY ON THURSDAY WITH GENERAL VFR CONDITIONS EXPECTED AWAY FROM ANY SCT AFTERNOON STORMS. && .MARINE... A STALLED FRONTAL BOUNDARY OVER CENTRAL FLORIDA WILL DISSIPATE TODAY. ANY SHOWERS ASSOCIATED WITH THIS BOUNDARY WILL MOVE FROM THE COASTAL WATERS INLAND THIS AFTERNOON. AS THIS BOUNDARY DISSIPATES...WINDS AND RAIN CHANCES WILL DECREASE OVER THE NEXT FEW DAYS. ANY CHANCE OF SHOWERS OR STORMS WILL OCCUR EARLY MORNING THEN TRANSITIONING INLAND DURING THE AFTERNOON. EVEN WITH A DECREASING CHANCE OF SHOWERS AND STORMS...THERE WILL STILL BE LOCALLY HIGHER WINDS AND SEAS IN AND AROUND ISOLATED THUNDERSTORMS. && .PRELIMINARY POINT TEMPS/POPS... TPA 74 88 74 89 / 10 30 10 30 FMY 75 91 75 90 / 20 30 10 30 GIF 73 91 72 90 / 20 40 20 40 SRQ 73 87 73 88 / 10 30 10 30 BKV 68 89 70 89 / 20 40 10 30 SPG 75 89 77 89 / 10 30 10 30 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...NONE. && $$ UPDATE/AVIATION...MROCZKA MARINE...MCKAUGHAN
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
1041 PM EDT WED OCT 1 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE FORECAST AREA THROUGH THURSDAY NIGHT. A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY NIGHT AND EARLY SATURDAY MORNING. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR AHEAD OF THE FRONT. THE COOLEST TEMPERATURES OF THE SEASON SO FAR WILL FOLLOW THE FRONT. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... ZONAL FLOW ALOFT WILL BECOME MORE NORTHWESTERLY TOWARD DAYBREAK AS A CLOSED UPPER LOW OVER THE NEW ENGLAND COAST SHIFTS EASTWARD AND A WEAK UPPER RIDGE BUILDS OVER THE SOUTHEASTERN STATES. AT THE SURFACE...WEAK HIGH PRESSURE WILL CONTINUE OVER THE AREA. SKIES WILL BE MOSTLY CLEAR AND WINDS WILL GENERALLY BE LIGHT AND VARIABLE OR CALM. THERE WILL LIKELY BE SOME PATCHY FOG TOWARDS MORNING...ESPECIALLY IN LOW LYING NORMALLY COLDER AREAS. NEARLY IDEAL RADIATIONAL COOLING CONDITIONS WILL SUPPORT LOWS OVERNIGHT AROUND 60. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... DRY WEATHER PATTERN WILL CONTINUE THROUGH THE DAY ON THURSDAY...LASTING INTO THE EARLY PART OF THURSDAY NIGHT. MODELS CONTINUE TO SHOW A STRONG UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT MOVING TOWARDS THE REGION LATE THURSDAY NIGHT. RAIN CHANCES WILL BE ON THE INCREASE LATE THURSDAY NIGHT ACROSS MUCH OF THE UPSTATE...BUT EXPECTING THE CWA TO REMAIN DRY DURING THE THURSDAY NIGHT TIME PERIOD. AS FOR FRIDAY...RAIN CHANCES INCREASE FROM WEST TO EAST THROUGH THE MORNING AS THE FRONT APPROACHES AND MOISTURE INCREASES IN ADVANCE OF THE PASSAGE. SHOWERS...WITH SOME THUNDERSTORM ACTIVITY...ARE EXPECTED AT SOME POINT THROUGH THE DAY AND EVENING HOURS FRIDAY. CAN NOT RULE OUT A STRONG STORM LATER IN THE AFTERNOON DUE TO SOME STRONGER SHEAR AND INSTABILITY DURING THAT TIME. AS FOR THE ACTUAL FRONTAL PASSAGE...TIMING STILL A LITTLE BIT OF AN ISSUE...WITH THE GFS BEING A LITTLE FASTER WITH THE MOVEMENT THAN THE NAM. FRONTAL PASSAGE WILL LIKELY NOT OCCUR UNTIL FRIDAY NIGHT...WITH THE RAIN CHANCES THEN DIMINISHING RAPIDLY ON THE BACKSIDE OF THE FRONT. SATURDAY SHOULD BE DRY AS THE FRONT MOVES EAST OF THE REGION. WINDS THROUGH THE DAY MAY BE RATHER STRONG AND GUSTY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AT THIS POINT IT APPEARS AS IF THE DRY AIR BEHIND THE COLD FRONT WILL BE ABLE TO DOMINATE THE WEATHER THROUGH MUCH OF THE LONGER TERM PERIOD. UPPER TROUGHING OVER THE EASTERN PART OF THE NATION SHOULD MAINTAIN BELOW NORMAL TEMPERATURES. GUIDANCE INDICATING THAT WE SHOULD EXPERIENCE COOLEST TEMPERATURES SATURDAY NIGHT AND SUNDAY NIGHT WITH LOWS MAINLY IN THE MIDDLE 40S TO AROUND 50. THESE TEMPERATURES WILL BE THE COOLEST SO FAR THIS SEASON. READINGS WILL BEGIN TO WARM BACK UP DURING THE EARLY PART OF NEXT WEEK. && .AVIATION /03Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BE OVER THE AREA THROUGH THE TAF PERIOD. MOSTLY CLEAR SKIES AND NEAR CALM WIND WILL AID THE DEVELOPMENT OF FOG OVERNIGHT...PARTICULARLY AT KAGS AND KOGB. ALREADY SEEING A DECLINE IN VSBY AT KAGS. THE RAP AND NAM MODELS INDICATED A LOW LEVEL JET OVERNIGHT...THEREBY LIMITING FOG. THE HRRR SHOWED MVFR FOG AROUND SUNRISE. SHOULD SEE AT LEAST PATCHY MVFR FOG DEVELOP BEFORE SUNRISE AS THE NOCTURNAL JET WEAKENS. HAVE INDICATED MVFR/IFR FOG AT KAGS/KOGB THROUGH 13Z. FORECASTED MVFR FOG AT KCAE/KCUB/DNL AROUND SUNRISE. CONDITIONS SHOULD IMPROVE TO VFR AROUND 13Z. WINDS WILL BE SOUTH TO SOUTHWEST DURING THE AFTERNOON WITH SCATTERED CLOUDS 4 KFT TO 6 KFT. EXTENDED AVIATION OUTLOOK...FOG AND LOW CLOUDS COULD BRING RESTRICTIONS EARLY FRIDAY MORNING. RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS FRIDAY AFTERNOON AND FRIDAY NIGHT AS A COLD FRONT CROSSES THE REGION. POST FRONTAL GUSTY WINDS COULD DEVELOP SATURDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
829 PM EDT WED OCT 1 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE FORECAST AREA THROUGH THURSDAY NIGHT. A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY NIGHT AND EARLY SATURDAY MORNING. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR AHEAD OF THE FRONT. THE COOLEST TEMPERATURES OF THE SEASON SO FAR WILL FOLLOW THE FRONT. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... ZONAL FLOW ALOFT WILL BECOME MORE NORTHWESTERLY TOWARD DAYBREAK AS A CLOSED UPPER LOW OVER THE NEW ENGLAND COAST SHIFTS EASTWARD AND A WEAK UPPER RIDGE BUILDS OVER THE SOUTHEASTERN STATES. AT THE SURFACE...WEAK HIGH PRESSURE WILL CONTINUE OVER THE AREA. SKIES WILL BE MOSTLY CLEAR AND WINDS WILL GENERALLY BE LIGHT AND VARIABLE OR CALM. THERE WILL LIKELY BE SOME PATCHY FOG TOWARDS MORNING...ESPECIALLY IN LOW LYING NORMALLY COLDER AREAS. NEARLY IDEAL RADIATIONAL COOLING CONDITIONS WILL SUPPORT LOWS OVERNIGHT AROUND 60. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... DRY WEATHER PATTERN WILL CONTINUE THROUGH THE DAY ON THURSDAY...LASTING INTO THE EARLY PART OF THURSDAY NIGHT. MODELS CONTINUE TO SHOW A STRONG UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT MOVING TOWARDS THE REGION LATE THURSDAY NIGHT. RAIN CHANCES WILL BE ON THE INCREASE LATE THURSDAY NIGHT ACROSS MUCH OF THE UPSTATE...BUT EXPECTING THE CWA TO REMAIN DRY DURING THE THURSDAY NIGHT TIME PERIOD. AS FOR FRIDAY...RAIN CHANCES INCREASE FROM WEST TO EAST THROUGH THE MORNING AS THE FRONT APPROACHES AND MOISTURE INCREASES IN ADVANCE OF THE PASSAGE. SHOWERS...WITH SOME THUNDERSTORM ACTIVITY...ARE EXPECTED AT SOME POINT THROUGH THE DAY AND EVENING HOURS FRIDAY. CAN NOT RULE OUT A STRONG STORM LATER IN THE AFTERNOON DUE TO SOME STRONGER SHEAR AND INSTABILITY DURING THAT TIME. AS FOR THE ACTUAL FRONTAL PASSAGE...TIMING STILL A LITTLE BIT OF AN ISSUE...WITH THE GFS BEING A LITTLE FASTER WITH THE MOVEMENT THAN THE NAM. FRONTAL PASSAGE WILL LIKELY NOT OCCUR UNTIL FRIDAY NIGHT...WITH THE RAIN CHANCES THEN DIMINISHING RAPIDLY ON THE BACKSIDE OF THE FRONT. SATURDAY SHOULD BE DRY AS THE FRONT MOVES EAST OF THE REGION. WINDS THROUGH THE DAY MAY BE RATHER STRONG AND GUSTY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AT THIS POINT IT APPEARS AS IF THE DRY AIR BEHIND THE COLD FRONT WILL BE ABLE TO DOMINATE THE WEATHER THROUGH MUCH OF THE LONGER TERM PERIOD. UPPER TROUGHING OVER THE EASTERN PART OF THE NATION SHOULD MAINTAIN BELOW NORMAL TEMPERATURES. GUIDANCE INDICATING THAT WE SHOULD EXPERIENCE COOLEST TEMPERATURES SATURDAY NIGHT AND SUNDAY NIGHT WITH LOWS MAINLY IN THE MIDDLE 40S TO AROUND 50. THESE TEMPERATURES WILL BE THE COOLEST SO FAR THIS SEASON. READINGS WILL BEGIN TO WARM BACK UP DURING THE EARLY PART OF NEXT WEEK. && .AVIATION /01Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BE OVER THE AREA THROUGH THE TAF PERIOD. MOSTLY CLEAR SKIES AND NEAR CALM WIND WILL AID THE DEVELOPMENT OF PATCHY FOG/STRATUS AFTER 06Z...PARTICULARLY AT KAGS AND KOGB. THE RAP AND NAM MODELS INDICATED A LOW LEVEL JET DEVELOPING OVERNIGHT...THEREBY LIMITING FOG. THE HRRR SHOWED MVFR FOG AROUND SUNRISE. SHOULD SEE AT LEAST PATCHY MVFR FOG DEVELOP JUST BEFORE SUNRISE AS THE NOCTURNAL JET WEAKENS. HAVE INDICATED VFR THROUGH 06Z THEN MVFR/IFR FOG AT KAGS AFTER 09Z. HAVE FORECASTED MVFR FOG AT KCAE/KCUB/KOGB/DNL AROUND SUNRISE. CONDITIONS SHOULD IMPROVE TO VFR AFTER 13Z. WINDS WILL BE SOUTH TO SOUTHWEST DURING THE AFTERNOON WITH SCATTERED CLOUDS 4 KFT TO 6 KFT. EXTENDED AVIATION OUTLOOK...FOG AND LOW CLOUDS COULD BRING RESTRICTIONS EARLY FRIDAY MORNING. RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS FRIDAY AFTERNOON AND FRIDAY NIGHT AS A COLD FRONT CROSSES THE REGION. POST FRONTAL GUSTY WINDS COULD DEVELOP SATURDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS COLUMBIA SC
755 PM EDT WED OCT 1 2014 .SYNOPSIS... HIGH PRESSURE WILL REMAIN OVER THE FORECAST AREA THROUGH THURSDAY NIGHT. A COLD FRONT WILL MOVE THROUGH THE AREA FRIDAY NIGHT AND EARLY SATURDAY MORNING. SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL OCCUR AHEAD OF THE FRONT. THE COOLEST TEMPERATURES OF THE SEASON SO FAR WILL FOLLOW THE FRONT. && .NEAR TERM /THROUGH TONIGHT/... HIGH PRESSURE WILL CONTINUE OVER THE AREA THROUGH TONIGHT. SKIES WILL BE MOSTLY CLEAR AND WINDS WILL GENERALLY BE LIGHT AND VARIABLE. THERE WILL LIKELY BE SOME PATCHY FOG TOWARDS MORNING...ESPECIALLY IN LOW LYING NORMALLY COLDER AREAS. LOWS TONIGHT FALLING TO AROUND 60. && .SHORT TERM /THURSDAY THROUGH SATURDAY/... DRY WEATHER PATTERN WILL CONTINUE THROUGH THE DAY ON THURSDAY...LASTING INTO THE EARLY PART OF THURSDAY NIGHT. MODELS CONTINUE TO SHOW A STRONG UPPER TROUGH AND ASSOCIATED SURFACE COLD FRONT MOVING TOWARDS THE REGION LATE THURSDAY NIGHT. RAIN CHANCES WILL BE ON THE INCREASE LATE THURSDAY NIGHT ACROSS MUCH OF THE UPSTATE...BUT EXPECTING THE CWA TO REMAIN DRY DURING THE THURSDAY NIGHT TIME PERIOD. AS FOR FRIDAY...RAIN CHANCES INCREASE FROM WEST TO EAST THROUGH THE MORNING AS THE FRONT APPROACHES AND MOISTURE INCREASES IN ADVANCE OF THE PASSAGE. SHOWERS...WITH SOME THUNDERSTORM ACTIVITY...ARE EXPECTED AT SOME POINT THROUGH THE DAY AND EVENING HOURS FRIDAY. CAN NOT RULE OUT A STRONG STORM LATER IN THE AFTERNOON DUE TO SOME STRONGER SHEAR AND INSTABILITY DURING THAT TIME. AS FOR THE ACTUAL FRONTAL PASSAGE...TIMING STILL A LITTLE BIT OF AN ISSUE...WITH THE GFS BEING A LITTLE FASTER WITH THE MOVEMENT THAN THE NAM. FRONTAL PASSAGE WILL LIKELY NOT OCCUR UNTIL FRIDAY NIGHT...WITH THE RAIN CHANCES THEN DIMINISHING RAPIDLY ON THE BACKSIDE OF THE FRONT. SATURDAY SHOULD BE DRY AS THE FRONT MOVES EAST OF THE REGION. WINDS THROUGH THE DAY MAY BE RATHER STRONG AND GUSTY. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... AT THIS POINT IT APPEARS AS IF THE DRY AIR BEHIND THE COLD FRONT WILL BE ABLE TO DOMINATE THE WEATHER THROUGH MUCH OF THE LONGER TERM PERIOD. UPPER TROUGHING OVER THE EASTERN PART OF THE NATION SHOULD MAINTAIN BELOW NORMAL TEMPERATURES. GUIDANCE INDICATING THAT WE SHOULD EXPERIENCE COOLEST TEMPERATURES SATURDAY NIGHT AND SUNDAY NIGHT WITH LOWS MAINLY IN THE MIDDLE 40S TO AROUND 50. THESE TEMPERATURES WILL BE THE COOLEST SO FAR THIS SEASON. READINGS WILL BEGIN TO WARM BACK UP DURING THE EARLY PART OF NEXT WEEK. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... HIGH PRESSURE WILL BE OVER THE AREA THROUGH THE TAF PERIOD. MOSTLY CLEAR SKIES AND NEAR CALM WIND WILL AID THE DEVELOPMENT OF PATCHY FOG/STRATUS AFTER 06Z...PARTICULARLY AT KAGS AND KOGB. THE RAP AND NAM MODELS INDICATED A LOW LEVEL JET DEVELOPING OVERNIGHT...THEREBY LIMITING FOG. THE HRRR SHOWED MVFR FOG AROUND SUNRISE. SHOULD SEE AT LEAST PATCHY MVFR FOG DEVELOP JUST BEFORE SUNRISE AS THE NOCTURNAL JET WEAKENS. HAVE INDICATED VFR THROUGH 06Z THEN MVFR/IFR FOG AT KAGS AFTER 09Z. HAVE FORECASTED MVFR FOG AT KCAE/KCUB/KOGB/DNL AROUND SUNRISE. CONDITIONS SHOULD IMPROVE TO VFR AFTER 13Z. WINDS WILL BE SOUTH TO SOUTHWEST DURING THE AFTERNOON WITH SCATTERED CLOUDS 4 KFT TO 6 KFT. EXTENDED AVIATION OUTLOOK...FOG AND LOW CLOUDS COULD BRING RESTRICTIONS EARLY FRIDAY MORNING. RESTRICTIONS POSSIBLE IN SHOWERS AND THUNDERSTORMS FRIDAY AFTERNOON AND FRIDAY NIGHT AS A COLD FRONT CROSSES THE REGION. POST FRONTAL GUSTY WINDS COULD DEVELOP SATURDAY. && .CAE WATCHES/WARNINGS/ADVISORIES... SC...NONE. GA...NONE. && $$
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
255 PM CDT TUE SEP 30 2014 .DISCUSSION... 238 PM CDT PLENTY TO KEEP US BUSY ON THE FORECAST DESK THIS AFTERNOON...WITH CONCERNS BEING CLOUD COVER AND TEMPERATURES TONIGHT FOLLOWED BY RAIN AND THUNDER POTENTIAL WEDNESDAY NIGHT THROUGH THURSDAY NIGHT...AND THEN FINALLY MUCH COOLER AIR AND SHOWER CHANCES THIS WEEKEND. TONIGHT... THIS AFTERNOON TEMPERATURES ARE RANGING 20 TO 30 DEGREES COLDER ACROSS NORTHERN ILLINOIS AND NORTHWEST INDIANA THAN YESTERDAY AFTERNOON. NORTHEAST FLOW IN THE BOUNDARY LAYER HAS KEPT THE INVERSION STRONG ESPECIALLY IN LAKE-BORDERING COUNTIES AND STRATUS HAS ACCORDINGLY BEEN SLOW TO DEPART. SURFACE RIDGING EXTENDING SOUTHWARD WILL MOVE OVER THE AREA TONIGHT AND WEAKEN THAT FLOW BUT ALSO ALLOWING FOR THE INVERSION TO REMAIN AND EVEN STRENGTHEN. CONFIDENCE IS OVERALL LOW ON SPECIFICS ON CLOUD COVER WITH THE STRATUS BEING ONLY ABOUT 1000 FT THICK PER AMDAR DATA. WHILE THERE MAY NOT BE THAT MUCH COVERAGE OF CLOUDS BY SUNDOWN...DO EXPECT THEREAFTER TO SEE AN INCREASE ALONG WITH A WESTWARD EXPANSION. GIVEN WHERE CLOUDS ARE NOW ON SATELLITE ALONG WITH A REASONABLE 4KM EMC WRF SOLUTION OF COLUMN CONDENSATE...WOULD ENVISION CLOUDS TO BECOME THE MOST WIDESPREAD ALONG AND NORTH OF INTERSTATE 80. LATER TONIGHT AS THE 850-925MB FLOW TURNS SOUTHERLY...THE CLEARING LINE MAY CREEP NORTHWARD. OBVIOUSLY TEMPERATURES WILL HINGE ON CLOUDS QUITE A BIT. OUTSIDE OF THE IMMEDIATE LAKE SHORE WHERE LOWER 50S ARE PROBABLE...40S ARE FORECAST BUT CLOUDS CLOUD DICTATE WHETHER NEAR 40 TO THE LOWER 50S. WEDNESDAY THROUGH THURSDAY NIGHT... A VERY ACTIVE PATTERN IS SEEN UPSTREAM WITH MULTIPLE UPPER CYCLONES AND TROUGHS ACROSS THE WESTERN HALF OF THE U.S. AND CANADA AND INTO THE NORTHERN PACIFIC. ONE WELL-DEFINED CYCLONE IS MOVING NEARLY DUE NORTH ACROSS THE DAKOTAS THIS AFTERNOON. ITS MOIST CONVEYOR BELT AND RAIN ENTERING WESTERN IA THIS AFTERNOON WILL EVENTUALLY WEAKEN AS IT SHIFTS EASTWARD THROUGH WEDNESDAY...BUT BEGIN TO RE-ENHANCE WEDNESDAY NIGHT AS THE NEXT DEEPER AND MORE PROGRESSIVE LONG WAVE TROUGH ENTERS THE PLAINS. EMBEDDED WITHIN THIS TROUGH WILL BE MULTIPLE VORT MAXS...GIVING THIS A NEGATIVE TILT OVER THE REGION THURSDAY NIGHT. THEN INTO FRIDAY IS WHEN A SURFACE LOW WILL DEEPEN CONSIDERABLY AS IT MOVES NORTHEAST FROM THE MID-MISSISSIPPI VALLEY THROUGH THE UPPER GREAT LAKES. SO AFTER A QUIET DAY WEDNESDAY WE CONTINUE TO SLOWLY SPREAD CHANCES OF RAIN EASTWARD WEDNESDAY NIGHT. INSTABILITY SUPPORTIVE OF THUNDER LAGS SOME AND BECOMES BETTER LATE IN THE NIGHT AND THROUGH THURSDAY. WHILE IT IS LIKELY THERE WILL BE AREAS OF RAIN WITH EMBEDDED STORMS IN THE REGION THURSDAY...THE MUCH BETTER SUPPORT IN UPPER LIFT...DEEP MOISTURE CONVERGENCE...AND EVEN INSTABILITY ARRIVES THURSDAY EVENING INTO OVERNIGHT ON THE SUITE OF GUIDANCE. THIS IS ESPECIALLY TRUE CONSIDERING THE SLOWING TREND THAT HAS BEEN SEEN OVER THE PAST FEW MODEL RUNS...SOMETHING ALMOST EXPECTED WITH SUCH AN AMPLIFIED AND DEEPENING SYSTEM. SO HAVE LIKELY POPS FOR MOST AREAS THURSDAY AND DEFINITE THURSDAY NIGHT. IT IS LIKELY MORE FOCUSED PERIODS FOR THE HIGHEST POPS WILL BE REFINED IN TIME. CONFIDENCE IS INCREASING FOR OVER AN INCH OF RAIN IN 18-24H WITH THIS SYSTEM /AND MAYBE EVEN IN A MUCH SHORTER TIME/ FOR MOST OF THE AREA DURING THURSDAY AND THURSDAY NIGHT...SUPPORTED BY CIPS AND GEFS ANALOG COMPOSITES. IT IS POSSIBLE FOR SOME LOCALIZED FLOODING BUT NOT EXPECTING WIDESPREAD ISSUES. THE SEVERE POTENTIAL CONTINUES TO LOOK TO BE SOUTHWEST OF THE AREA WHERE A SQUALL LINE IS FAVORED INTO SOUTHERN IL GIVEN THE SYNOPTICS. THE NORTHERN PORTION OF THIS...LIKELY MORE LOOSELY DEFINED...COULD CLIP OUR AREA...AS MODERATE LOWER AND UPPER LEVEL WIND SHEAR SHIFT OVER THE REGION AHEAD OF THE FRONT. OVERALL THE SEVERE WEATHER THREAT REMAINS LOW. FRIDAY THROUGH EARLY NEXT WEEK... THIS REMAINS A CHALLENGING PERIOD BUT CONFIDENCE HAS INCREASED THAT MUCH COOLER THAN NORMAL TEMPERATURES WILL BE PREVALENT THROUGH MUCH OF THIS PERIOD. THE UPPER LEVEL LOW/TROUGH WHICH BECOMES NEGATIVELY TILTED AT THE BEGINNING OF THIS PERIOD WILL BE FURTHER STRENGTHENED BY MULTIPLE UPPER JET MAXS. AS THIS OCCURS...COOLER THAN NORMAL LOW-LEVEL AIR WILL BE REPLENISHED. UPPER LEVEL DISTURBANCES...NAMELY SHEARED BUT STILL EACH WITH LAPSE RATES AND MOISTURE SUPPORTIVE OF SCATTERED SHOWERS...WILL BE SUPPORTED IN THIS PATTERN. IF THESE PASS OVER THE AREA THEY WILL ALLOW FOR SOME WET/CLOUDY/EVEN COOLER WEATHER. HAVE TRENDED COOLER IN MULTIPLE PERIODS BUT CONFIDENCE IS GENERALLY LOW ON SPECIFICS. IT IS POSSIBLE THAT PATCHY FROST MAY NEED TO BE ADDED TO THE FORECAST IN TIME DEPENDING ON CLOUD COVER AND WINDS. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * OCCASIONAL SPRINKLES THIS AFTERNOON. * MVFR CIGS THROUGH MID MORNING WEDNESDAY. BMD //DISCUSSION...UPDATED 18Z... A COLD FRONT LIES ACROSS DOWNSTATE IL AND SOUTHERN IN THIS AFTERNOON WITH BROAD AREA OF STRATUS BEHIND WHICH HAS BEGUN TO OVERTURN IN SOME AREAS ALLOWING SKIES TO SCATTER. THE CHICAGO TERMINALS REMAIN SOCKED IN UNDER MVFR STRATUS HOWEVER WITH MOISTURE FROM THE LAKE AND LAKE EFFECT CLOUDS/SPRINKLES EXPECTED TO KEEP MVFR CONDITIONS AT THE CHICAGO TERMINALS THROUGH THE REMAINDER OF THE DAY. WINDS WILL GRADUALLY BACK THROUGH THE DAY...FROM N/NNE EARLY THIS AFTERNOON TO NORTHEAST MID/LATE AFTERNOON...AND EVENTUALLY SOUTHEAST LATE TONIGHT. SOUTHEAST WINDS WILL CONTINUE THROUGH THE DAY WEDNESDAY. RFD IS EXPECTED TO SEE SKIES SCATTER OUT FOR A PERIOD THIS AFTERNOON AND EVENING...BUT MVFR CIGS MAY SPREAD BACK OVERHEAD TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 20Z... * HIGH CONFIDENCE IN GENERAL WIND DIRECTION TRENDS. MEDIUM CONFIDENCE IN WINDS STAYING NEAR 10 KT THIS AFTERNOON AND EVENING. * MEDIUM-HIGH CONFIDENCE THAT MVFR WILL CONTINUE THROUGH TONIGHT...THOUGH LOW CONFIDENCE IN END TIME FOR MVFR WEDNESDAY. BMD //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...INCREASING CHANCE FOR SHRA/TSRA. MVFR POSSIBLE. SOUTHEAST WINDS. THURSDAY...TSRA AND MVFR LIKELY. SOUTH WINDS. FRIDAY...LOW CHANCE SHRA. MVFR POSSIBLE EARLY. GUSTY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...VFR. SLIGHT CHANCE SHRA. SOUTHWEST WINDS. MONDAY...VFR. WEST WINDS. MDB && .MARINE... 215 PM CDT HIGH PRESSURE STRETCHING THROUGH SOUTHERN ONTARIO AND QUEBEC WILL CONTINUE DRIFTING EAST TONIGHT AS LOW PRESSURE NEAR THE EASTERN GREAT LAKES WEAKENS. WHILE WINDS ARE ABATING SOMEWHAT ACROSS LAKE MICHIGAN THIS AFTERNOON AS THE PRESSURE GRADIENT RELAXES...THE NORTHERLY FETCH IS HOLDING WAVES ALONG THE SOUTHERN THIRD OF THE LAKE AT 4-6 FT OR HIGHER. TONIGHT THE RIDGE AXIS ASSOCIATED WITH THE DEPARTING HIGH WILL PASS OVER THE LAKE THEN PUSH TO THE EASTERN LAKES THURSDAY. EXPECT A MORE SIGNIFICANT EASING OF THE WAVES AS THIS OCCURS. MEANWHILE...SEVERAL AREAS OF LOW PRESSURE IN THE PLAINS WILL ALLOW WINDS TO VEER TO SOUTHEASTLERLY. THE FIRST LOW IN WESTERN NEBRASKA WILL LIFT INTO MANITOBA WEDS THEN DEEPEN FURTHER AS IT CONTINUES TOWARD HUDSON BAY. A SECONDARY LOW WILL DEVELOP ACROSS THE SOUTHERN/CENTRAL PLAINS WEDNESDAY NIGHT. IT IS THIS LOW THAT WILL EJECT NORTHWESTWARD TOWARD THE WESTERN GREAT LAKES LATER IN THE WEEK. THIS LOW IS EXPECTED TO DEEPEN AS IT PASSES THROUGH WISCONSIN FRIDAY THAN NORTH INTO ONTARIO ON FRIDAY. EXPECT SOUTHEAST WINDS TO INCREASE IN RESPONSE TO THE STRENGTHENING LOW...WITH WINDS TO 30 KT POSSIBLE. AT THIS TIME IT APPEARS THAT THE STRONGEST WINDS ALOFT AHEAD OF THE LOW ON THURSDAY WILL HAVE A HARDER TIME SURFACING DUE TO THIS WESTERLY TRACK...BUT AS THE LOW LIFTS NORTH THERE MAY BE A BRIEF PERIOD OF SOUTHERLY GALES THURSDAY NIGHT. WHILE THE WINDS ALOFT SHOW SUPPORT FOR GALES...THERE IS STILL QUITE A BIT OF UNCERTAINTY WITH HOW DEEP THE LOW WILL BE AND HOW FAR EAST IT WILL BE DURING THIS PERIOD. ON THE BACK SIDE OF THE LOW WHICH SHOULD STILL BE STRENGTHENING NORTH OF THE LAKE...A SHARP COLD FRONT WILL BRING ANOTHER CHANCE FOR GALES...THIS TIME WITH WEST WINDS. THE WIND SUPPORT ALOFT WOULD SUGGEST JUST BORDERLINE GALE FORCE GUSTS...BUT IT WILL BE A PRETTY STRONG FRONT AND UNSTABLE CONDITIONS SHOULD ALLOW FOR BETTER MIXING. FOLLOWING THE FRONT A MODEST GRADIENT REMAINS IN PLACE THROUGH THE WEEKEND AHEAD OF A CLIPPER-LIKE LOW FOR MONDAY. KMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 255 PM CDT Tue Sep 30 2014 .SHORT TERM...(Tonight) ISSUED AT 255 PM CDT TUE SEP 30 2014 A cold front had pushed into southern IL and northeast MO this afternoon bringing cooler temperatures today. Meanwhile 1022 mb high pressure north of the Great Lakes was nosing southward into IL and combined with upper level ridge over IL had decrease the low clouds by early afternoon leaving patches of stratocumulus clouds along with a veil of cirrus clouds. Temps at mid afternoon ranged from the mid 60s over Knox, Stark and Marshall counties where low clouds still lingered, to upper 70s and lower 80s along and south of highway 50 in southeast IL. Upper level ridge axis near the MS river will shift east across IL and into Indiana by Wed morning while surface high pressure ridge extends into the Ohio river valley from the Great Lakes region. As the ridge axis shifts east of IL, ene winds to veer se on Wed as frontal boundary retreats back north as a warm front over central IL Wed. Dry conditions expected to prevail through Wed morning with fair skies. Patchy shallow/ground fog could develop during overnight due to low level moisture trapped in a strong inversion, but drier air advecting in today on ne winds with dewpoints slipping into the upper 40s and lower 50s from I-74 ne to limit fog formation. Southern and sw areas may have best chance of seeing patchy fog where higher dewpoints in the upper 50s to around 60F closer to the frontal boundary. Similar MAV/MET guidance lows tonight have trended cooler and leaned in that direction for tonights lows in the upper 40s and lower 50s, with mid 50s from Jacksonville sw. && .LONG TERM...(Wednesday through Tuesday) ISSUED AT 255 PM CDT TUE SEP 30 2014 Big changes on the horizon for Central and Southeast Illinois by the end of the week as much colder air is expected to push southeast into the Midwest. Energy in the form of a strong 500mb trough over Alaska is expected to dive down the west coast of North America and reinforce a developing longwave trough over the Central U.S. by late Thursday. In the meantime, the cold front that pushed through the area last night is expected to retreat back toward the northeast ahead of the initial trough developing currently over the Plains. Some questions remain as to how fast and far the front will be able to push across the area on Wednesday with the answer having major implications on the high temperature forecast. The GFS suggests that progress should be as far as I-74 while the NAM keeps temps below normal with the boundary remaining sw of the area. The 00z ECMWF is somewhere in between. SREF from 09z favors the warmer solution and will lean toward a compromise of the GFS/MAV and the ECMWF. As the mid-level trough deepens, with 130+ kt jet plunging into it, on Wednesday Night and Thursday, scattered precip is expect to develop across the Midwest. BUFkit model soundings suggest some capping possibly through middle afternoon in the warm sector with the NAM being the most unstable and loosing the cap by late afternoon in SW forecast area. In addition the cold front associated with the main trough is expected to enter western Illinois during the evening. The speed of the front is fairly consistent through the operational model suite and has been slowing with each run set. There should be some reduction in instability as the evening wears on but dynamics will likely be enough to keep strong storms going well into the evening along and ahead of the boundary. At this time it appears there may be some threat of hail with the storms ahead of the line with straight-line winds being the primary threat with the actual QLCS. Much colder air is expected Friday with lingering clouds and showers as 500mb temps approaching -30C are progged. Would not be surprised to see near steady temperatures and brisk conditions. Models may be underplaying winds as is often the case in these type of situatuions. By Saturday morning 850 mb temps drop blo 0C in all the operational suite. Clouds and winds should keep reduce the threat of frost, but would expect at least a few wind protected locations to have lows into the 30s. Reinforcing shots of energy move through the trough over the weekend and into next week. Timing of individual features are difficult this far out and the models show generally cool and partly to mostly cloudy conditions but varying timing and chances for precipitation. Overall heights slowly build early next week, but will generally reduce precip and introduce only gradual warming given the uncertainty. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1250 PM CDT TUE SEP 30 2014 Shallow layer of stratocumulus clouds 1-2k ft thick dissipating rapidly over central IL by midday due to strong subsidence from surface and upper level ridge over IL. Cloud bases lifted to 1500 ft and have recently scattered out over the central IL airports past hour or two, most recently at western airports of PIA and SPI. RAP and NAM curule does not show much redevelopment of cumulus clouds this afternoon so will keep just scattered cumulus clouds 2-4k ft. Shallow moisture layer will be trapped by strong inversion overnight and lead to some fog development. For now have introduced MVFR vsbys from 08-14Z, but could see locally lower vsbys late tonight/early Wed morning especially at SPI and DEC where dewpoints a few degrees higher. HRRR model shows stratus clouds and some fog advecting westward from Lake MI across northern IL with light east flow and these clouds to stay north of central IL tonight. Scattered cumulus clouds 4-5k ft to appear after 15Z/10 am Wed across central IL. NE winds near 10 kts this afternoon to become light east after sunset and SE near 10 kts after 15Z Tue as front in southern IL retreats back north across central IL Wed. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...07 LONG TERM...Barker AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
217 PM CDT TUE SEP 30 2014 .DISCUSSION... 1110 AM CDT HAVE ONLY MADE MINOR ADJUSTMENTS TO GOING FORECAST...MAINLY IN SLIGHT DOWNWARD ADJUSTMENTS TO HIGH TEMPERATURES IN PORTIONS OF NORTHERN ILLINOIS...PARTICULARLY NEAR THE WISCONSIN BORDER AND NEAR LAKE MICHIGAN. LATEST VISIBLE SATELLITE IMAGERY IS SHOWING HOLES DEVELOPING IN THE STRATUS DECK OVER INLAND AREAS DUE TO DRIER AIR AND STILL RELATIVELY STRONG END OF SEPTEMBER SUN. THESE AREAS SHOULD BE ABLE TO WARM INTO THE LOWER TO MID 60S...WITH A FEW UPPER 60S IN CENTRAL IL. NEAR THE LAKE...DESPITE SOME DRYING ...COOL NORTH-NORTHEAST BOUNDARY LAYER FLOW IS WRINGING OUT MOISTURE IN THE FORM OF OCCASIONAL SPRINKLES...WHICH GIVEN LITTLE CHANGE IN CONDITIONS SHOULD PERSIST THROUGH AT LEAST EARLY AFTERNOON. HAVE UPDATED GRIDS TO HAVE OCCASIONAL DRIZZLE MENTION IN FAVORED LAKE EFFECT AREAS THROUGH THIS TIME. TEMPERATURES WILL STRUGGLE TO WARM TO BETWEEN 55 AND 60 DEGREES DUE TO PERSISTENT OVERCAST. AS ALLUDED TO ABOVE...HAVE ALSO ADJUSTED HIGHS DOWNWARD SLIGHTLY TO UPPER 50S TO AROUND 60 FOR INLAND AREAS NEAR WI BORDER...AS VISIBLE SATELLITE SUGGESTS STRATUS IS THICKER THERE AND SOME AREAS INCLUDING RFD ARE STILL IN UPPER 40S AS OF THIS WRITING. RC //PREV DISCUSSION... 332 AM CDT MAIN FORECAST CONCERNS/CHALLENGES ARE WITH CLOUD COVER AND TEMPS TODAY...AND THEN INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS LATE WEDNESDAY NIGHT INTO THURSDAY AND THURSDAY NIGHT. COLD FRONT NOW SOUTH OF THE CWA EARLY THIS MORNING AS LOW STRATUS HAS MOVED OVER MUCH OF THE REGION...WHILE TEMPS CONTINUE TO FALL INTO THE 40S AND 50S UNDER A STEADY NORTHEAST WIND. WITH ISOLATED SHOWERS NOW EAST OF THE CWA EXPECT DRY CONDITIONS TODAY BUT WITH THIS STRATUS LIKELY HANGING AROUND FOR SOME TIME THIS MORNING. GUIDANCE APPEARING TO BE TOO QUICK SCATTERING OUT THESE CLOUDS THIS MORNING AND TRYING TO INDICATE THERE WILL BE HOLES BY 12Z. WITH THIS NOT A LIKELY SCENARIO HAVE GONE MORE PESSIMISTIC WITH TRENDS THIS MORNING AND DONT HAVE ANY REAL CLEARING UNTIL LATE MORNING/MIDDAY. MOST AREAS WILL LIKELY OBSERVE A SCATTERING TREND INTO THE AFTERNOON...BUT WITH AREAS NEAR THE LAKE HOLDING ONTO THESE CLOUDS FOR MUCH OF THE DAY. DID LOWER HIGH TEMPS AS WELL AS SLOWED TEMP TREND THIS MORNING...WITH IT POSSIBLE FOR LOCATIONS IN FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA NOT MAKING IT OUT OF THE 50S TODAY. QUIET BUT COOL NIGHT TONIGHT AS BOUNDARY LAYER FLOW VEERS AND ANY LINGERING CLOUD COVER COMING OFF THE LAKE PUSHES NORTH INTO WISCONSIN LATER THIS EVENING...AND MOST LOCATIONS OBSERVING CLEAR TO PARTLY CLOUDY SKIES. FAIRLY ENERGETIC VORT MAX CURRENTLY LIFTING NORTH THROUGH THE CENTRAL PLAINS WILL CONTINUE NORTH INTO THE NORTHERN PLAINS TODAY INTO TONIGHT. AS THIS OCCURS...UPPER LEVEL RIDGING WILL BE BRIEF TONIGHT AS RIDGE AXIS SHIFTS TO THE EAST AND WE QUICKLY TRANSITION TOWARDS A SOUTHWEST FLOW PATTERN. THIS WILL ALLOW FOR A PERIOD OF WAA GOING INTO WEDNESDAY WITH TEMPS REBOUNDING BACK INTO THE 70S FOR MOST LOCATIONS. MADE MINIMAL CHANGES TO GOING FORECAST HIGHS ON WEDNESDAY AS UNCERTAINTY WITH APPROACHING MID/HIGH LEVEL CLOUD COVER COULD PLAY INTO THE EXTENT OF WARMING THAT OCCURS. THE BEST WAA/MOIST ADVECTION WILL REMAIN JUST TO THE WEST FOR MOST OF THE DAY WEDNESDAY BUT THIS WILL CHANGE WEDNESDAY NIGHT AS MID/UPPER LEVEL TROUGH DIGS ACROSS THE CENTRAL PLAINS...AND STRENGTHENING LLJ BECOMES ORIENTED TOWARDS NORTHERN ILLINOIS. THIS COINCIDING WITH FAIRLY ENERGETIC MID LEVEL FLOW...DEVELOPING PRECIP SHIELD SHOULD BEGIN REACHING MOST LOCATIONS IN NORTHERN ILLINOIS AFTER THE MIDNIGHT TIME FRAME. DESPITE INCREASING INSTABILITY WEDNESDAY NIGHT...INSTABILITY AXIS DOES APPEAR TO STAY JUST TO THE WEST/SOUTHWEST OF THE CWA DURING THIS TIME. ALTHOUGH THIS MAY BE THE CASE...STRENGTHENING LLJ COULD OFFSET ANY LACKING INSTABILITY AND SO HAVE MAINTAINED CHANCE THUNDER WORDING OVER THE ENTIRE CWA...WITH THE FAR WEST AND SOUTHWEST AREAS LIKELY OBSERVING BEST CHANCES FOR THUNDER. MOISTURE WILL CONTINUE TO INCREASE DURING THIS TIME AND DO FEEL THERE COULD BE SOME PERIODS OF MORE MODERATE RAINFALL...BUT THIS WONT LIKELY OCCUR UNTIL VERY LATE IN THE NIGHT AND TOWARDS EARLY THURSDAY MORNING. BETTER AGREEMENT OBSERVED WITH VARYING MODELS THIS MORNING REGARDING APPROACHING MID/UPPER LEVEL TROUGH AND ASSOCIATED SURFACE FEATURE THURSDAY AND THURSDAY NIGHT. SURFACE LOW SHOULD LIFT RIGHT ALONG THE MISSISSIPPI RIVER AREA INTO SOUTHWEST WISCONSIN THURSDAY AND THEN INTO THE GREAT LAKES REGION THURSDAY NIGHT. CONTINUED LARGE SCALE SUPPORT DURING THIS PERIOD WILL ALLOW FOR A WET DAY THURSDAY INTO THURSDAY NIGHT AS PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY. A SLOWER DEPARTING TREND WILL OCCUR THURSDAY NIGHT...AND DID KEEP LIKELY WORDING LONGER INTO THE NIGHT. ALTHOUGH MOISTURE AND INSTABILITY WILL CONTINUE TO INCREASE DURING THIS TIME...IT DOES LOOK LIKE THE BEST INSTABILITY WILL REMAIN SOUTH OF THE CWA. SO AT THIS TIME...AM NOT OVERLY CONCERNED WITH ANY SEVERE POTENTIAL BUT AM MORE CONCERNED WITH HEAVY RAINFALL AND POSSIBLE LOCALIZED FLOODING...ESPECIALLY AS THE BEST OVERALL MOIST ADVECTION OCCURS INTO THURSDAY NIGHT. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * OCCASIONAL SPRINKLES THIS AFTERNOON. * MVFR CIGS THROUGH MID MORNING WEDNESDAY. BMD //DISCUSSION...UPDATED 18Z... A COLD FRONT LIES ACROSS DOWNSTATE IL AND SOUTHERN IN THIS AFTERNOON WITH BROAD AREA OF STRATUS BEHIND WHICH HAS BEGUN TO OVERTURN IN SOME AREAS ALLOWING SKIES TO SCATTER. THE CHICAGO TERMINALS REMAIN SOCKED IN UNDER MVFR STRATUS HOWEVER WITH MOISTURE FROM THE LAKE AND LAKE EFFECT CLOUDS/SPRINKLES EXPECTED TO KEEP MVFR CONDITIONS AT THE CHICAGO TERMINALS THROUGH THE REMAINDER OF THE DAY. WINDS WILL GRADUALLY BACK THROUGH THE DAY...FROM N/NNE EARLY THIS AFTERNOON TO NORTHEAST MID/LATE AFTERNOON...AND EVENTUALLY SOUTHEAST LATE TONIGHT. SOUTHEAST WINDS WILL CONTINUE THROUGH THE DAY WEDNESDAY. RFD IS EXPECTED TO SEE SKIES SCATTER OUT FOR A PERIOD THIS AFTERNOON AND EVENING...BUT MVFR CIGS MAY SPREAD BACK OVERHEAD TONIGHT. BMD //ORD AND MDW CONFIDENCE...UPDATED 18Z... * HIGH CONFIDENCE IN GENERAL WIND DIRECTION TRENDS. MEDIUM CONFIDENCE IN WINDS STAYING NEAR 10 KT THIS AFTERNOON AND EVENING. * MEDIUM-HIGH CONFIDENCE THAT MVFR WILL CONTINUE THROUGH TONIGHT...THOUGH LOW CONFIDENCE IN END TIME FOR MVFR WEDNESDAY. BMD //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...INCREASING CHANCE FOR SHRA/TSRA. MVFR POSSIBLE. SOUTHEAST WINDS. THURSDAY...TSRA AND MVFR LIKELY. SOUTH WINDS. FRIDAY...LOW CHANCE SHRA. MVFR POSSIBLE EARLY. GUSTY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...VFR. SLIGHT CHANCE SHRA. SOUTHWEST WINDS. MONDAY...VFR. WEST WINDS. MDB && .MARINE... 215 PM CDT HIGH PRESSURE STRETCHING THROUGH SOUTHERN ONTARIO AND QUEBEC WILL CONTINUE DRIFTING EAST TONIGHT AS LOW PRESSURE NEAR THE EASTERN GREAT LAKES WEAKENS. WHILE WINDS ARE ABATING SOMEWHAT ACROSS LAKE MICHIGAN THIS AFTERNOON AS THE PRESSURE GRADIENT RELAXES...THE NORTHERLY FETCH IS HOLDING WAVES ALONG THE SOUTHERN THIRD OF THE LAKE AT 4-6 FT OR HIGHER. TONIGHT THE RIDGE AXIS ASSOCIATED WITH THE DEPARTING HIGH WILL PASS OVER THE LAKE THEN PUSH TO THE EASTERN LAKES THURSDAY. EXPECT A MORE SIGNIFICANT EASING OF THE WAVES AS THIS OCCURS. MEANWHILE...SEVERAL AREAS OF LOW PRESSURE IN THE PLAINS WILL ALLOW WINDS TO VEER TO SOUTHEASTLERLY. THE FIRST LOW IN WESTERN NEBRASKA WILL LIFT INTO MANITOBA WEDS THEN DEEPEN FURTHER AS IT CONTINUES TOWARD HUDSON BAY. A SECONDARY LOW WILL DEVELOP ACROSS THE SOUTHERN/CENTRAL PLAINS WEDNESDAY NIGHT. IT IS THIS LOW THAT WILL EJECT NORTHWESTWARD TOWARD THE WESTERN GREAT LAKES LATER IN THE WEEK. THIS LOW IS EXPECTED TO DEEPEN AS IT PASSES THROUGH WISCONSIN FRIDAY THAN NORTH INTO ONTARIO ON FRIDAY. EXPECT SOUTHEAST WINDS TO INCREASE IN RESPONSE TO THE STRENGTHENING LOW...WITH WINDS TO 30 KT POSSIBLE. AT THIS TIME IT APPEARS THAT THE STRONGEST WINDS ALOFT AHEAD OF THE LOW ON THURSDAY WILL HAVE A HARDER TIME SURFACING DUE TO THIS WESTERLY TRACK...BUT AS THE LOW LIFTS NORTH THERE MAY BE A BRIEF PERIOD OF SOUTHERLY GALES THURSDAY NIGHT. WHILE THE WINDS ALOFT SHOW SUPPORT FOR GALES...THERE IS STILL QUITE A BIT OF UNCERTAINTY WITH HOW DEEP THE LOW WILL BE AND HOW FAR EAST IT WILL BE DURING THIS PERIOD. ON THE BACK SIDE OF THE LOW WHICH SHOULD STILL BE STRENGTHENING NORTH OF THE LAKE...A SHARP COLD FRONT WILL BRING ANOTHER CHANCE FOR GALES...THIS TIME WITH WEST WINDS. THE WIND SUPPORT ALOFT WOULD SUGGEST JUST BORDERLINE GALE FORCE GUSTS...BUT IT WILL BE A PRETTY STRONG FRONT AND UNSTABLE CONDITIONS SHOULD ALLOW FOR BETTER MIXING. FOLLOWING THE FRONT A MODEST GRADIENT REMAINS IN PLACE THROUGH THE WEEKEND AHEAD OF A CLIPPER-LIKE LOW FOR MONDAY. KMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1254 PM CDT Tue Sep 30 2014 .UPDATE... ISSUED AT 1040 AM CDT TUE SEP 30 2014 Updated the forecast earlier this morning to have patchy fog into midday along and south of a Quincy to Jacksonville to Taylorville to Robinson line and locally dense this morning from Jacksonville sw. Also adjusted cloud cover and highs today, with low clouds getting into southeast IL as they slowly drift south toward highway 50 from Flora to Olney to Lawrenceville. Cloud bases of 500-1500 ft and even less than 500 feet in southern counties where fog is present. Pilot reports show cloud deck about 1-2k ft thick and starting to break up in ne counties late this morning where drier air has worked in on ne winds as dewpoints slipped into upper 40s and lower 50s. Low clouds should continue to break up from the ne and sw with skies becoming partly to mostly sunny during the afternoon. Temps currently 55-60F except low to mid 60s se of I-70 and Mount Carmel airport up to 72F and still enjoying sunny skies. The cold front has pushed just south of CWA with ne winds 6-12 mph and low clouds blanketing much of CWA. Cold front to weaken as it pushes into southern IL this afternoon/evening and low clouds to decrease during the afternoon. Highs mostly in the low to mid 70s over central IL, but to range from 65-70F from I-74 northeast, to the lower 80s along and south of highway 50. && .SHORT TERM...(Today) ISSUED AT 312 AM CDT TUE SEP 30 2014 Short-term forecast concerns include potential for dense fog across the southern KILX CWA, as well as, approaching deck of low clouds across the north. Clear skies/light winds have once again led to the development of fog early this morning, particularly from the Saint Louis area eastward across southern Illinois. HRRR shows fog becoming dense across this area over the next few hours before dissipating after 8am. So far the fog has not become widespread or dense, but based on forecast soundings and the HRRR, have included patchy dense fog south of I-70. Have also issued a Special Weather Statement to highlight the low visbys. 07z/2am surface analysis shows cold front settling southward into central Illinois, with a widespread area of low clouds noted to the north of the boundary across the Great Lakes into north-central Illinois. Latest IR satellite imagery shows leading edge of clouds along the I-74 corridor. Main questions today will be how far south these clouds will push and whether or not they will clear out this afternoon. Satellite timing tools suggest the clouds will reach a Rushville to Mattoon line by daybreak, but additional southward progress appears unlikely as frontal boundary stalls. Will therefore go with a cloudy forecast across the northern two-thirds of the CWA this morning, with mostly sunny skies across the far south. Despite continued northeasterly flow behind the front, forecast soundings indicate a gradual dissipation of low-level moisture as the day progresses. Have gone with decreasing clouds through the afternoon accordingly. Due to the cloud cover and shift in wind direction, temps will be quite a bit cooler today than in recent days, with afternoon highs ranging from the upper 60s along/north of I-74 to around 80 far south. && .LONG TERM...(Tonight through Monday) ISSUED AT 312 AM CDT TUE SEP 30 2014 Winds will veer to the southeast on Wednesday in response to an approaching upper wave and its associated cold front. As a result, temperatures will rise back into the upper 70s and lower 80s. As a deep upper trough slowly approaches from the west, surface low pressure is expected to develop over the Southern Plains on Wednesday then lift northward into the Great Lakes by Thursday night. Warm-advection showers/thunder will develop ahead of this system Wednesday night: however, all model guidance keeps any precip focused mainly across the western half of the CWA. Given this slowing trend, have removed PoPs for all locations along/east of a Paris to Effingham line. Further west, will go with likely PoPs across the Illinois River Valley after midnight. As surface low deepens and tracks just west of the area on Thursday, strong S/SW flow will provide one more very warm day with highs in the upper 70s/lower 80s. Showers and thunderstorms will develop in advance of a slowly approaching cold front, mainly focused across the west. With strong upper dynamics in place and increasing amounts of moisture flowing northward from the Gulf of Mexico, a few strong to severe thunderstorms will be possible Thursday afternoon across west-central Illinois. Once low lifts into the Great Lakes, front will get a solid push eastward by Thursday evening. Will go with categorical PoPs across the board as the boundary interacts with a moist and moderately unstable environment. Cold front will push into Indiana by early Friday morning, with perhaps a few lingering showers across the Wabash River Valley. Main weather story late in the week will be the sharply cooler conditions. 850mb temps are progged to drop into the 0 to -2C range by Saturday morning, supporting daytime highs only in the lower to middle 60s and overnight lows in the lower 40s this weekend. Airmass will slowly moderate by early next week, with temperatures climbing back to around 70 by Monday. && .AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon) ISSUED AT 1250 PM CDT TUE SEP 30 2014 Shallow layer of stratocumulus clouds 1-2k ft thick dissipating rapidly over central IL by midday due to strong subsidence from surface and upper level ridge over IL. Cloud bases lifted to 1500 ft and have recently scattered out over the central IL airports past hour or two, most recently at western airports of PIA and SPI. RAP and NAM curule does not show much redevelopment of cumulus clouds this afternoon so will keep just scattered cumulus clouds 2-4k ft. Shallow moisture layer will be trapped by strong inversion overnight and lead to some fog development. For now have introduced MVFR vsbys from 08-14Z, but could see locally lower vsbys late tonight/early Wed morning especially at SPI and DEC where dewpoints a few degrees higher. HRRR model shows stratus clouds and some fog advecting westward from Lake MI across northern IL with light east flow and these clouds to stay north of central IL tonight. Scattered cumulus clouds 4-5k ft to appear after 15Z/10 am Wed across central IL. NE winds near 10 kts this afternoon to become light east after sunset and SE near 10 kts after 15Z Tue as front in southern IL retreats back north across central IL Wed. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...07 SHORT TERM...Barnes LONG TERM...Barnes AVIATION...07
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT TUE SEP 30 2014 .DISCUSSION... 332 AM CDT MAIN FORECAST CONCERNS/CHALLENGES ARE WITH CLOUD COVER AND TEMPS TODAY...AND THEN INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS LATE WEDNESDAY NIGHT INTO THURSDAY AND THURSDAY NIGHT. COLD FRONT NOW SOUTH OF THE CWA EARLY THIS MORNING AS LOW STRATUS HAS MOVED OVER MUCH OF THE REGION...WHILE TEMPS CONTINUE TO FALL INTO THE 40S AND 50S UNDER A STEADY NORTHEAST WIND. WITH ISOLATED SHOWERS NOW EAST OF THE CWA EXPECT DRY CONDITIONS TODAY BUT WITH THIS STRATUS LIKELY HANGING AROUND FOR SOME TIME THIS MORNING. GUIDANCE APPEARING TO BE TOO QUICK SCATTERING OUT THESE CLOUDS THIS MORNING AND TRYING TO INDICATE THERE WILL BE HOLES BY 12Z. WITH THIS NOT A LIKELY SCENARIO HAVE GONE MORE PESSIMISTIC WITH TRENDS THIS MORNING AND DONT HAVE ANY REAL CLEARING UNTIL LATE MORNING/MIDDAY. MOST AREAS WILL LIKELY OBSERVE A SCATTERING TREND INTO THE AFTERNOON...BUT WITH AREAS NEAR THE LAKE HOLDING ONTO THESE CLOUDS FOR MUCH OF THE DAY. DID LOWER HIGH TEMPS AS WELL AS SLOWED TEMP TREND THIS MORNING...WITH IT POSSIBLE FOR LOCATIONS IN FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA NOT MAKING IT OUT OF THE 50S TODAY. QUIET BUT COOL NIGHT TONIGHT AS BOUNDARY LAYER FLOW VEERS AND ANY LINGERING CLOUD COVER COMING OFF THE LAKE PUSHES NORTH INTO WISCONSIN LATER THIS EVENING...AND MOST LOCATIONS OBSERVING CLEAR TO PARTLY CLOUDY SKIES. FAIRLY ENERGETIC VORT MAX CURRENTLY LIFTING NORTH THROUGH THE CENTRAL PLAINS WILL CONTINUE NORTH INTO THE NORTHERN PLAINS TODAY INTO TONIGHT. AS THIS OCCURS...UPPER LEVEL RIDGING WILL BE BRIEF TONIGHT AS RIDGE AXIS SHIFTS TO THE EAST AND WE QUICKLY TRANSITION TOWARDS A SOUTHWEST FLOW PATTERN. THIS WILL ALLOW FOR A PERIOD OF WAA GOING INTO WEDNESDAY WITH TEMPS REBOUNDING BACK INTO THE 70S FOR MOST LOCATIONS. MADE MINIMAL CHANGES TO GOING FORECAST HIGHS ON WEDNESDAY AS UNCERTAINTY WITH APPROACHING MID/HIGH LEVEL CLOUD COVER COULD PLAY INTO THE EXTENT OF WARMING THAT OCCURS. THE BEST WAA/MOIST ADVECTION WILL REMAIN JUST TO THE WEST FOR MOST OF THE DAY WEDNESDAY BUT THIS WILL CHANGE WEDNESDAY NIGHT AS MID/UPPER LEVEL TROUGH DIGS ACROSS THE CENTRAL PLAINS...AND STRENGTHENING LLJ BECOMES ORIENTED TOWARDS NORTHERN ILLINOIS. THIS COINCIDING WITH FAIRLY ENERGETIC MID LEVEL FLOW...DEVELOPING PRECIP SHIELD SHOULD BEGIN REACHING MOST LOCATIONS IN NORTHERN ILLINOIS AFTER THE MIDNIGHT TIME FRAME. DESPITE INCREASING INSTABILITY WEDNESDAY NIGHT...INSTABILITY AXIS DOES APPEAR TO STAY JUST TO THE WEST/SOUTHWEST OF THE CWA DURING THIS TIME. ALTHOUGH THIS MAY BE THE CASE...STRENGTHENING LLJ COULD OFFSET ANY LACKING INSTABILITY AND SO HAVE MAINTAINED CHANCE THUNDER WORDING OVER THE ENTIRE CWA...WITH THE FAR WEST AND SOUTHWEST AREAS LIKELY OBSERVING BEST CHANCES FOR THUNDER. MOISTURE WILL CONTINUE TO INCREASE DURING THIS TIME AND DO FEEL THERE COULD BE SOME PERIODS OF MORE MODERATE RAINFALL...BUT THIS WONT LIKELY OCCUR UNTIL VERY LATE IN THE NIGHT AND TOWARDS EARLY THURSDAY MORNING. BETTER AGREEMENT OBSERVED WITH VARYING MODELS THIS MORNING REGARDING APPROACHING MID/UPPER LEVEL TROUGH AND ASSOCIATED SURFACE FEATURE THURSDAY AND THURSDAY NIGHT. SURFACE LOW SHOULD LIFT RIGHT ALONG THE MISSISSIPPI RIVER AREA INTO SOUTHWEST WISCONSIN THURSDAY AND THEN INTO THE GREAT LAKES REGION THURSDAY NIGHT. CONTINUED LARGE SCALE SUPPORT DURING THIS PERIOD WILL ALLOW FOR A WET DAY THURSDAY INTO THURSDAY NIGHT AS PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY. A SLOWER DEPARTING TREND WILL OCCUR THURSDAY NIGHT...AND DID KEEP LIKELY WORDING LONGER INTO THE NIGHT. ALTHOUGH MOISTURE AND INSTABILITY WILL CONTINUE TO INCREASE DURING THIS TIME...IT DOES LOOK LIKE THE BEST INSTABILITY WILL REMAIN SOUTH OF THE CWA. SO AT THIS TIME...AM NOT OVERLY CONCERNED WITH ANY SEVERE POTENTIAL BUT AM MORE CONCERNED WITH HEAVY RAINFALL AND POSSIBLE LOCALIZED FLOODING...ESPECIALLY AS THE BEST OVERALL MOIST ADVECTION OCCURS INTO THURSDAY NIGHT. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * PERIODIC LAKE EFFECT SPRINKLES THROUGH THE AFTERNOON. * MVFR CIGS THROUGH REST OF TODAY. * N TO NE WINDS AROUND 10 KT TODAY. BMD //DISCUSSION...UPDATED 12Z... LARGE AREA OF 1000-1500 FT CIGS IS SPREAD ACROSS THE REGION THIS MORNING. RADAR MOSAIC SHOWS A NARROW BAND OF LAKE EFFECT LIGHT RAIN/DRIZZLE OFFSHORE OF KMKE SOUTHWARD TO ORD/MDW. THIS IS PRODUCING IFR CIGS AND MVFR VSBY. WINDS ON THE WEST SIDE OF THIS BAND HAVE TURNED NNW WITH NNE WINDS ON THE EAST SIDE OF THE BAND. EXPECT THIS BAND TO SLOWLY PIVOT EASTWARD INTO MID MORNING BUT IN THE MEANTIME ORD/MDW WILL LIKELY BE IN AND OUT OF IFR CIGS AND MVFR VSBY IN DRIZZLE. ONCE THE BAND SHIFTS EAST OR EVEN DISSIPATES WINDS SHOULD TURN NNE THEN FURTHER NORTHEAST INTO THE AFTERNOON. SPEEDS LOOK TO REMAIN AROUND 10 KT. ONCE THE IFR IMPROVES MVFR WILL PERSIST BUT SHOULD SEE SCATTERING TOWARDS RFD/DPA THIS AFTERNOON WITH FLOW OFF THE LAKE LIKELY KEEPING MVFR CIGS AT ORD/MDW/GYY THROUGH THE DAY...THOUGH SCATTERING IS POSSIBLE. LOW LEVEL WINDS WILL TURN SOUTHEASTERLY THIS EVENING WHICH WILL PUSH THE LOW LEVEL MOISTURE AND ASSOCIATED CLOUD COVER TO THE NORTHWEST. THERE MAY BE SOME EXPANSION OF COVERAGE AS THIS OCCURS SO RFD/DPA MAY GET BACK INTO MVFR BUT WILL KEEP COVERAGE SCATTERED FOR NOW. DO NOT HAVE A GREAT DEAL OF CONFIDENCE IN TIMING OF CIG EVOLUTION TONIGHT AND MAY BE HOLDING ONTO THEM TOO LONG. SKIES DO LOOK TO HAVE SCATTERED OR LESS COVERAGE WEDNESDAY MORNING. MDB //ORD AND MDW CONFIDENCE...UPDATED 16Z... * HIGH CONFIDENCE IN SLOWLY RISING MVFR CIGS REST OF THIS AFTERNOON. LOW CONFIDENCE IN HOW LONG THEY MAY LAST. * HIGH CONFIDENCE IN WIND TRENDS. MEDIUM CONFIDENCE THAT SPEEDS WILL BE 10 KT OR LESS THIS AFTERNOON. BMD //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...INCREASING CHANCE FOR SHRA/TSRA. MVFR POSSIBLE. SOUTHEAST WINDS. THURSDAY...TSRA AND MVFR LIKELY. SOUTH WINDS. FRIDAY...LOW CHANCE SHRA. MVFR POSSIBLE EARLY. GUSTY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...VFR. SLIGHT CHANCE SHRA. SOUTHWEST WINDS. MONDAY...VFR. WEST WINDS. MDB && .MARINE... 257 AM CDT STRONG NORTHERLY WINDS WILL GRADUALLY DECREASE IN SPEED INTO THE AFTERNOON AS HIGH PRESSURE RIDGING MOVES ACROSS LAKE MICHIGAN. THE PRESSURE GRADIENT WILL TIGHTEN UP SOMEWHAT WEDNESDAY AS THE RIDGE SHIFTS EAST AND LOW PRESSURE OVER THE CENTRAL HIGH PLAINS TRACKS NORTH TO MANITOBA BY WEDNESDAY AFTERNOON. THIS WILL ALLOW WINDS TO SHIFT TO THE SOUTHEAST TONIGHT. WILL CONTINUE WITH THE SMALL CRAFT ADVISORY THROUGH THIS AFTERNOON. STEADY SOUTH TO SOUTHEAST WINDS WILL CONTINUE INTO THURSDAY WHEN LOW PRESSURE DEVELOPS OVER THE TEXAS/OKLAHOMA PANHANDLE AND TRACKS NORTHEAST TO THE U.P. OF MICHIGAN THURSDAY NIGHT. FORECAST MODELS HAVE STRUGGLED WITH THE TRACK AND INTENSITY OF THIS SYSTEM THOUGH THERE HAS BEEN VERY GENERAL AGREEMENT IN THE LOW TRACKING NORTHWEST OF THE LAKE AND DEEPENING WHILE DOING SO. WHILE SPECIFICS ARE STILL UNDETERMINED THE STAGE WILL BE SET FOR A PERIOD OF STRONGER WINDS ACROSS THE LAKE...STARTING OUT SOUTHERLY THEN TURNING WESTERLY AS A COLD FRONT PASSES THURSDAY NIGHT. SEVERAL OTHER MORE SUBTLE SURFACE TROUGHS MAY CROSS FRIDAY INTO SATURDAY ALLOWING WINDS TO FLUCTUATE BETWEEN WEST AND NORTHWEST. A PERIOD OF GALES STILL LOOKS POSSIBLE...PRIMARILY AFTER THE PASSAGE OF THE MAIN FRONT AS COLDER AIR SPREADS IN. WIND SPEEDS WILL GRADUALLY EASE GOING INTO SUNDAY. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1040 AM CDT Tue Sep 30 2014 .UPDATE... ISSUED AT 1040 AM CDT TUE SEP 30 2014 Updated the forecast earlier this morning to have patchy fog into midday along and south of a Quincy to Jacksonville to Taylorville to Robinson line and locally dense this morning from Jacksonville sw. Also adjusted cloud cover and highs today, with low clouds getting into southeast IL as they slowly drift south toward highway 50 from Flora to Olney to Lawrenceville. Cloud bases of 500-1500 ft and even less than 500 feet in southern counties where fog is present. Pilot reports show cloud deck about 1-2k ft thick and starting to break up in ne counties late this morning where drier air has worked in on ne winds as dewpoints slipped into upper 40s and lower 50s. Low clouds should continue to break up from the ne and sw with skies becoming partly to mostly sunny during the afternoon. Temps currently 55-60F except low to mid 60s se of I-70 and Mount Carmel airport up to 72F and still enjoying sunny skies. The cold front has pushed just south of CWA with ne winds 6-12 mph and low clouds blanketing much of CWA. Cold front to weaken as it pushes into southern IL this afternoon/evening and low clouds to decrease during the afternoon. Highs mostly in the low to mid 70s over central IL, but to range from 65-70F from I-74 northeast, to the lower 80s along and south of highway 50. && .SHORT TERM...(Today) ISSUED AT 312 AM CDT TUE SEP 30 2014 Short-term forecast concerns include potential for dense fog across the southern KILX CWA, as well as, approaching deck of low clouds across the north. Clear skies/light winds have once again led to the development of fog early this morning, particularly from the Saint Louis area eastward across southern Illinois. HRRR shows fog becoming dense across this area over the next few hours before dissipating after 8am. So far the fog has not become widespread or dense, but based on forecast soundings and the HRRR, have included patchy dense fog south of I-70. Have also issued a Special Weather Statement to highlight the low visbys. 07z/2am surface analysis shows cold front settling southward into central Illinois, with a widespread area of low clouds noted to the north of the boundary across the Great Lakes into north-central Illinois. Latest IR satellite imagery shows leading edge of clouds along the I-74 corridor. Main questions today will be how far south these clouds will push and whether or not they will clear out this afternoon. Satellite timing tools suggest the clouds will reach a Rushville to Mattoon line by daybreak, but additional southward progress appears unlikely as frontal boundary stalls. Will therefore go with a cloudy forecast across the northern two-thirds of the CWA this morning, with mostly sunny skies across the far south. Despite continued northeasterly flow behind the front, forecast soundings indicate a gradual dissipation of low-level moisture as the day progresses. Have gone with decreasing clouds through the afternoon accordingly. Due to the cloud cover and shift in wind direction, temps will be quite a bit cooler today than in recent days, with afternoon highs ranging from the upper 60s along/north of I-74 to around 80 far south. && .LONG TERM...(Tonight through Monday) ISSUED AT 312 AM CDT TUE SEP 30 2014 Winds will veer to the southeast on Wednesday in response to an approaching upper wave and its associated cold front. As a result, temperatures will rise back into the upper 70s and lower 80s. As a deep upper trough slowly approaches from the west, surface low pressure is expected to develop over the Southern Plains on Wednesday then lift northward into the Great Lakes by Thursday night. Warm-advection showers/thunder will develop ahead of this system Wednesday night: however, all model guidance keeps any precip focused mainly across the western half of the CWA. Given this slowing trend, have removed PoPs for all locations along/east of a Paris to Effingham line. Further west, will go with likely PoPs across the Illinois River Valley after midnight. As surface low deepens and tracks just west of the area on Thursday, strong S/SW flow will provide one more very warm day with highs in the upper 70s/lower 80s. Showers and thunderstorms will develop in advance of a slowly approaching cold front, mainly focused across the west. With strong upper dynamics in place and increasing amounts of moisture flowing northward from the Gulf of Mexico, a few strong to severe thunderstorms will be possible Thursday afternoon across west-central Illinois. Once low lifts into the Great Lakes, front will get a solid push eastward by Thursday evening. Will go with categorical PoPs across the board as the boundary interacts with a moist and moderately unstable environment. Cold front will push into Indiana by early Friday morning, with perhaps a few lingering showers across the Wabash River Valley. Main weather story late in the week will be the sharply cooler conditions. 850mb temps are progged to drop into the 0 to -2C range by Saturday morning, supporting daytime highs only in the lower to middle 60s and overnight lows in the lower 40s this weekend. Airmass will slowly moderate by early next week, with temperatures climbing back to around 70 by Monday. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 700 AM CDT TUE SEP 30 2014 The cold front has pushed south of all TAF sites, with northeast winds around 10-14kt in its wake. A short period of LIFR fog and ceilings have developed along the leading edge of the clouds at SPI and DEC with 200FT ceilings and 1/2sm FG. Behind the front, IFR conditions with ceilings of 400-800 ft and p6sm vis have developed within 2 hours of FROPA. Based on the latest observation trends, ceilings should improve to the MVFR by late morning. The main concern is how soon the clouds will erode to VFR, with all the low level moisture trapped under a developing subsidence inversion. Latest guidance off the NAM-WRF and HRRR continues to suggest we will see some breaks develop by late morning or early afternoon. Will continue with the previous trends in the TAFs in scattering out the lower cigs by afternoon with some broken VFR cigs into the late afternoon hours. Southern TAFS of DEC and SPI should see VFR the soonest, and possibly as early as 11 am or Noon. The gusty northeast winds immediately behind the front will settle out in the 8 to 14 kt range for much of the day. Mixing heights will be limited by the low ceiling heights, so gusts should not get to 20kt at any point. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...07 SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
839 AM CDT TUE SEP 30 2014 .DISCUSSION... 332 AM CDT MAIN FORECAST CONCERNS/CHALLENGES ARE WITH CLOUD COVER AND TEMPS TODAY...AND THEN INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS LATE WEDNESDAY NIGHT INTO THURSDAY AND THURSDAY NIGHT. COLD FRONT NOW SOUTH OF THE CWA EARLY THIS MORNING AS LOW STRATUS HAS MOVED OVER MUCH OF THE REGION...WHILE TEMPS CONTINUE TO FALL INTO THE 40S AND 50S UNDER A STEADY NORTHEAST WIND. WITH ISOLATED SHOWERS NOW EAST OF THE CWA EXPECT DRY CONDITIONS TODAY BUT WITH THIS STRATUS LIKELY HANGING AROUND FOR SOME TIME THIS MORNING. GUIDANCE APPEARING TO BE TOO QUICK SCATTERING OUT THESE CLOUDS THIS MORNING AND TRYING TO INDICATE THERE WILL BE HOLES BY 12Z. WITH THIS NOT A LIKELY SCENARIO HAVE GONE MORE PESSIMISTIC WITH TRENDS THIS MORNING AND DONT HAVE ANY REAL CLEARING UNTIL LATE MORNING/MIDDAY. MOST AREAS WILL LIKELY OBSERVE A SCATTERING TREND INTO THE AFTERNOON...BUT WITH AREAS NEAR THE LAKE HOLDING ONTO THESE CLOUDS FOR MUCH OF THE DAY. DID LOWER HIGH TEMPS AS WELL AS SLOWED TEMP TREND THIS MORNING...WITH IT POSSIBLE FOR LOCATIONS IN FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA NOT MAKING IT OUT OF THE 50S TODAY. QUIET BUT COOL NIGHT TONIGHT AS BOUNDARY LAYER FLOW VEERS AND ANY LINGERING CLOUD COVER COMING OFF THE LAKE PUSHES NORTH INTO WISCONSIN LATER THIS EVENING...AND MOST LOCATIONS OBSERVING CLEAR TO PARTLY CLOUDY SKIES. FAIRLY ENERGETIC VORT MAX CURRENTLY LIFTING NORTH THROUGH THE CENTRAL PLAINS WILL CONTINUE NORTH INTO THE NORTHERN PLAINS TODAY INTO TONIGHT. AS THIS OCCURS...UPPER LEVEL RIDGING WILL BE BRIEF TONIGHT AS RIDGE AXIS SHIFTS TO THE EAST AND WE QUICKLY TRANSITION TOWARDS A SOUTHWEST FLOW PATTERN. THIS WILL ALLOW FOR A PERIOD OF WAA GOING INTO WEDNESDAY WITH TEMPS REBOUNDING BACK INTO THE 70S FOR MOST LOCATIONS. MADE MINIMAL CHANGES TO GOING FORECAST HIGHS ON WEDNESDAY AS UNCERTAINTY WITH APPROACHING MID/HIGH LEVEL CLOUD COVER COULD PLAY INTO THE EXTENT OF WARMING THAT OCCURS. THE BEST WAA/MOIST ADVECTION WILL REMAIN JUST TO THE WEST FOR MOST OF THE DAY WEDNESDAY BUT THIS WILL CHANGE WEDNESDAY NIGHT AS MID/UPPER LEVEL TROUGH DIGS ACROSS THE CENTRAL PLAINS...AND STRENGTHENING LLJ BECOMES ORIENTED TOWARDS NORTHERN ILLINOIS. THIS COINCIDING WITH FAIRLY ENERGETIC MID LEVEL FLOW...DEVELOPING PRECIP SHIELD SHOULD BEGIN REACHING MOST LOCATIONS IN NORTHERN ILLINOIS AFTER THE MIDNIGHT TIME FRAME. DESPITE INCREASING INSTABILITY WEDNESDAY NIGHT...INSTABILITY AXIS DOES APPEAR TO STAY JUST TO THE WEST/SOUTHWEST OF THE CWA DURING THIS TIME. ALTHOUGH THIS MAY BE THE CASE...STRENGTHENING LLJ COULD OFFSET ANY LACKING INSTABILITY AND SO HAVE MAINTAINED CHANCE THUNDER WORDING OVER THE ENTIRE CWA...WITH THE FAR WEST AND SOUTHWEST AREAS LIKELY OBSERVING BEST CHANCES FOR THUNDER. MOISTURE WILL CONTINUE TO INCREASE DURING THIS TIME AND DO FEEL THERE COULD BE SOME PERIODS OF MORE MODERATE RAINFALL...BUT THIS WONT LIKELY OCCUR UNTIL VERY LATE IN THE NIGHT AND TOWARDS EARLY THURSDAY MORNING. BETTER AGREEMENT OBSERVED WITH VARYING MODELS THIS MORNING REGARDING APPROACHING MID/UPPER LEVEL TROUGH AND ASSOCIATED SURFACE FEATURE THURSDAY AND THURSDAY NIGHT. SURFACE LOW SHOULD LIFT RIGHT ALONG THE MISSISSIPPI RIVER AREA INTO SOUTHWEST WISCONSIN THURSDAY AND THEN INTO THE GREAT LAKES REGION THURSDAY NIGHT. CONTINUED LARGE SCALE SUPPORT DURING THIS PERIOD WILL ALLOW FOR A WET DAY THURSDAY INTO THURSDAY NIGHT AS PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY. A SLOWER DEPARTING TREND WILL OCCUR THURSDAY NIGHT...AND DID KEEP LIKELY WORDING LONGER INTO THE NIGHT. ALTHOUGH MOISTURE AND INSTABILITY WILL CONTINUE TO INCREASE DURING THIS TIME...IT DOES LOOK LIKE THE BEST INSTABILITY WILL REMAIN SOUTH OF THE CWA. SO AT THIS TIME...AM NOT OVERLY CONCERNED WITH ANY SEVERE POTENTIAL BUT AM MORE CONCERNED WITH HEAVY RAINFALL AND POSSIBLE LOCALIZED FLOODING...ESPECIALLY AS THE BEST OVERALL MOIST ADVECTION OCCURS INTO THURSDAY NIGHT. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 14Z... * PERIODIC IFR CIGS IN LAKE EFFECT CLOUD/DRIZZLE BAND FOR THE NEXT FEW HOURS. * CIGS GRADUALLY LIFTING LATE MORNING INTO THE AFTERNOON BUT REMAINING MVFR...POSSIBLY THROUGH THE EVENING. PERIOD OF SCATTERING POSSIBLE THIS AFTERNOON. * N WINDS WITH LAKE EFFECT BAND NEXT FEW HOURS BUT SHIFT TO NNE EXPECTED BY MID/LATE MORNING...GOING FURTHER NORTHEAST INTO THE AFTERNOON. SPEEDS AROUND 10 KT. MDB/BMD //DISCUSSION...UPDATED 12Z... LARGE AREA OF 1000-1500 FT CIGS IS SPREAD ACROSS THE REGION THIS MORNING. RADAR MOSAIC SHOWS A NARROW BAND OF LAKE EFFECT LIGHT RAIN/DRIZZLE OFFSHORE OF KMKE SOUTHWARD TO ORD/MDW. THIS IS PRODUCING IFR CIGS AND MVFR VSBY. WINDS ON THE WEST SIDE OF THIS BAND HAVE TURNED NNW WITH NNE WINDS ON THE EAST SIDE OF THE BAND. EXPECT THIS BAND TO SLOWLY PIVOT EASTWARD INTO MID MORNING BUT IN THE MEANTIME ORD/MDW WILL LIKELY BE IN AND OUT OF IFR CIGS AND MVFR VSBY IN DRIZZLE. ONCE THE BAND SHIFTS EAST OR EVEN DISSIPATES WINDS SHOULD TURN NNE THEN FURTHER NORTHEAST INTO THE AFTERNOON. SPEEDS LOOK TO REMAIN AROUND 10 KT. ONCE THE IFR IMPROVES MVFR WILL PERSIST BUT SHOULD SEE SCATTERING TOWARDS RFD/DPA THIS AFTERNOON WITH FLOW OFF THE LAKE LIKELY KEEPING MVFR CIGS AT ORD/MDW/GYY THROUGH THE DAY...THOUGH SCATTERING IS POSSIBLE. LOW LEVEL WINDS WILL TURN SOUTHEASTERLY THIS EVENING WHICH WILL PUSH THE LOW LEVEL MOISTURE AND ASSOCIATED CLOUD COVER TO THE NORTHWEST. THERE MAY BE SOME EXPANSION OF COVERAGE AS THIS OCCURS SO RFD/DPA MAY GET BACK INTO MVFR BUT WILL KEEP COVERAGE SCATTERED FOR NOW. DO NOT HAVE A GREAT DEAL OF CONFIDENCE IN TIMING OF CIG EVOLUTION TONIGHT AND MAY BE HOLDING ONTO THEM TOO LONG. SKIES DO LOOK TO HAVE SCATTERED OR LESS COVERAGE WEDNESDAY MORNING. MDB //ORD AND MDW CONFIDENCE...UPDATED 14Z... * HIGH CONFIDENCE IN AT LEAST PERIODIC IFR NEXT FEW HOURS. MEDIUM CONFIDENCE IN END TIME OF IFR. * HIGH CONFIDENCE IN MVFR CIGS THROUGH THE DAY WITH BASES RISING THROUGH AFTERNOON. MEDIUM CONFIDENCE IN MVFR CIGS THIS EVENING/TONIGHT...BUT LOW CONFIDENCE IN HOW LONG THEY MAY LAST. LOW CONFIDENCE IN POTENTIAL FOR A PERIOD OF SCATTERING THIS AFTERNOON. * HIGH CONFIDENCE IN WIND TRENDS. MEDIUM CONFIDENCE THAT SPEEDS WILL BE 10 KT OR LESS THIS AFTERNOON. MDB/BMD //OUTLOOK FOR ORD/MDW FOR 00Z THURSDAY-12Z TUESDAY...UPDATED 12Z... WEDNESDAY NIGHT...INCREASING CHANCE FOR SHRA/TSRA. MVFR POSSIBLE. SOUTHEAST WINDS. THURSDAY...TSRA AND MVFR LIKELY. SOUTH WINDS. FRIDAY...LOW CHANCE SHRA. MVFR POSSIBLE EARLY. GUSTY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...VFR. SLIGHT CHANCE SHRA. SOUTHWEST WINDS. MONDAY...VFR. WEST WINDS. MDB && .MARINE... 257 AM CDT STRONG NORTHERLY WINDS WILL GRADUALLY DECREASE IN SPEED INTO THE AFTERNOON AS HIGH PRESSURE RIDGING MOVES ACROSS LAKE MICHIGAN. THE PRESSURE GRADIENT WILL TIGHTEN UP SOMEWHAT WEDNESDAY AS THE RIDGE SHIFTS EAST AND LOW PRESSURE OVER THE CENTRAL HIGH PLAINS TRACKS NORTH TO MANITOBA BY WEDNESDAY AFTERNOON. THIS WILL ALLOW WINDS TO SHIFT TO THE SOUTHEAST TONIGHT. WILL CONTINUE WITH THE SMALL CRAFT ADVISORY THROUGH THIS AFTERNOON. STEADY SOUTH TO SOUTHEAST WINDS WILL CONTINUE INTO THURSDAY WHEN LOW PRESSURE DEVELOPS OVER THE TEXAS/OKLAHOMA PANHANDLE AND TRACKS NORTHEAST TO THE U.P. OF MICHIGAN THURSDAY NIGHT. FORECAST MODELS HAVE STRUGGLED WITH THE TRACK AND INTENSITY OF THIS SYSTEM THOUGH THERE HAS BEEN VERY GENERAL AGREEMENT IN THE LOW TRACKING NORTHWEST OF THE LAKE AND DEEPENING WHILE DOING SO. WHILE SPECIFICS ARE STILL UNDETERMINED THE STAGE WILL BE SET FOR A PERIOD OF STRONGER WINDS ACROSS THE LAKE...STARTING OUT SOUTHERLY THEN TURNING WESTERLY AS A COLD FRONT PASSES THURSDAY NIGHT. SEVERAL OTHER MORE SUBTLE SURFACE TROUGHS MAY CROSS FRIDAY INTO SATURDAY ALLOWING WINDS TO FLUCTUATE BETWEEN WEST AND NORTHWEST. A PERIOD OF GALES STILL LOOKS POSSIBLE...PRIMARILY AFTER THE PASSAGE OF THE MAIN FRONT AS COLDER AIR SPREADS IN. WIND SPEEDS WILL GRADUALLY EASE GOING INTO SUNDAY. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 702 AM CDT Tue Sep 30 2014 .SHORT TERM...(Today) ISSUED AT 312 AM CDT TUE SEP 30 2014 Short-term forecast concerns include potential for dense fog across the southern KILX CWA, as well as, approaching deck of low clouds across the north. Clear skies/light winds have once again led to the development of fog early this morning, particularly from the Saint Louis area eastward across southern Illinois. HRRR shows fog becoming dense across this area over the next few hours before dissipating after 8am. So far the fog has not become widespread or dense, but based on forecast soundings and the HRRR, have included patchy dense fog south of I-70. Have also issued a Special Weather Statement to highlight the low visbys. 07z/2am surface analysis shows cold front settling southward into central Illinois, with a widespread area of low clouds noted to the north of the boundary across the Great Lakes into north-central Illinois. Latest IR satellite imagery shows leading edge of clouds along the I-74 corridor. Main questions today will be how far south these clouds will push and whether or not they will clear out this afternoon. Satellite timing tools suggest the clouds will reach a Rushville to Mattoon line by daybreak, but additional southward progress appears unlikely as frontal boundary stalls. Will therefore go with a cloudy forecast across the northern two-thirds of the CWA this morning, with mostly sunny skies across the far south. Despite continued northeasterly flow behind the front, forecast soundings indicate a gradual dissipation of low-level moisture as the day progresses. Have gone with decreasing clouds through the afternoon accordingly. Due to the cloud cover and shift in wind direction, temps will be quite a bit cooler today than in recent days, with afternoon highs ranging from the upper 60s along/north of I-74 to around 80 far south. && .LONG TERM...(Tonight through Monday) ISSUED AT 312 AM CDT TUE SEP 30 2014 Winds will veer to the southeast on Wednesday in response to an approaching upper wave and its associated cold front. As a result, temperatures will rise back into the upper 70s and lower 80s. As a deep upper trough slowly approaches from the west, surface low pressure is expected to develop over the Southern Plains on Wednesday then lift northward into the Great Lakes by Thursday night. Warm-advection showers/thunder will develop ahead of this system Wednesday night: however, all model guidance keeps any precip focused mainly across the western half of the CWA. Given this slowing trend, have removed PoPs for all locations along/east of a Paris to Effingham line. Further west, will go with likely PoPs across the Illinois River Valley after midnight. As surface low deepens and tracks just west of the area on Thursday, strong S/SW flow will provide one more very warm day with highs in the upper 70s/lower 80s. Showers and thunderstorms will develop in advance of a slowly approaching cold front, mainly focused across the west. With strong upper dynamics in place and increasing amounts of moisture flowing northward from the Gulf of Mexico, a few strong to severe thunderstorms will be possible Thursday afternoon across west-central Illinois. Once low lifts into the Great Lakes, front will get a solid push eastward by Thursday evening. Will go with categorical PoPs across the board as the boundary interacts with a moist and moderately unstable environment. Cold front will push into Indiana by early Friday morning, with perhaps a few lingering showers across the Wabash River Valley. Main weather story late in the week will be the sharply cooler conditions. 850mb temps are progged to drop into the 0 to -2C range by Saturday morning, supporting daytime highs only in the lower to middle 60s and overnight lows in the lower 40s this weekend. Airmass will slowly moderate by early next week, with temperatures climbing back to around 70 by Monday. && .AVIATION...(For the 12Z TAFS through 12Z Wednesday morning) ISSUED AT 700 AM CDT TUE SEP 30 2014 The cold front has pushed south of all TAF sites, with northeast winds around 10-14kt in its wake. A short period of LIFR fog and ceilings have developed along the leading edge of the clouds at SPI and DEC with 200FT ceilings and 1/2sm FG. Behind the front, IFR conditions with ceilings of 400-800 ft and p6sm vis have developed within 2 hours of FROPA. Based on the latest observation trends, ceilings should improve to the MVFR by late morning. The main concern is how soon the clouds will erode to VFR, with all the low level moisture trapped under a developing subsidence inversion. Latest guidance off the NAM-WRF and HRRR continues to suggest we will see some breaks develop by late morning or early afternoon. Will continue with the previous trends in the TAFs in scattering out the lower cigs by afternoon with some broken VFR cigs into the late afternoon hours. Southern TAFS of DEC and SPI should see VFR the soonest, and possibly as early as 11 am or Noon. The gusty northeast winds immediately behind the front will settle out in the 8 to 14 kt range for much of the day. Mixing heights will be limited by the low ceiling heights, so gusts should not get to 20kt at any point. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
336 AM CDT TUE SEP 30 2014 .DISCUSSION... 332 AM CDT MAIN FORECAST CONCERNS/CHALLENGES ARE WITH CLOUD COVER AND TEMPS TODAY...AND THEN INCREASING CHANCES FOR SHOWERS AND THUNDERSTORMS LATE WEDNESDAY NIGHT INTO THURSDAY AND THURSDAY NIGHT. COLD FRONT NOW SOUTH OF THE CWA EARLY THIS MORNING AS LOW STRATUS HAS MOVED OVER MUCH OF THE REGION...WHILE TEMPS CONTINUE TO FALL INTO THE 40S AND 50S UNDER A STEADY NORTHEAST WIND. WITH ISOLATED SHOWERS NOW EAST OF THE CWA EXPECT DRY CONDITIONS TODAY BUT WITH THIS STRATUS LIKELY HANGING AROUND FOR SOME TIME THIS MORNING. GUIDANCE APPEARING TO BE TOO QUICK SCATTERING OUT THESE CLOUDS THIS MORNING AND TRYING TO INDICATE THERE WILL BE HOLES BY 12Z. WITH THIS NOT A LIKELY SCENARIO HAVE GONE MORE PESSIMISTIC WITH TRENDS THIS MORNING AND DONT HAVE ANY REAL CLEARING UNTIL LATE MORNING/MIDDAY. MOST AREAS WILL LIKELY OBSERVE A SCATTERING TREND INTO THE AFTERNOON...BUT WITH AREAS NEAR THE LAKE HOLDING ONTO THESE CLOUDS FOR MUCH OF THE DAY. DID LOWER HIGH TEMPS AS WELL AS SLOWED TEMP TREND THIS MORNING...WITH IT POSSIBLE FOR LOCATIONS IN FAR NORTHEAST ILLINOIS AND NORTHWEST INDIANA NOT MAKING IT OUT OF THE 50S TODAY. QUIET BUT COOL NIGHT TONIGHT AS BOUNDARY LAYER FLOW VEERS AND ANY LINGERING CLOUD COVER COMING OFF THE LAKE PUSHES NORTH INTO WISCONSIN LATER THIS EVENING...AND MOST LOCATIONS OBSERVING CLEAR TO PARTLY CLOUDY SKIES. FAIRLY ENERGETIC VORT MAX CURRENTLY LIFTING NORTH THROUGH THE CENTRAL PLAINS WILL CONTINUE NORTH INTO THE NORTHERN PLAINS TODAY INTO TONIGHT. AS THIS OCCURS...UPPER LEVEL RIDGING WILL BE BRIEF TONIGHT AS RIDGE AXIS SHIFTS TO THE EAST AND WE QUICKLY TRANSITION TOWARDS A SOUTHWEST FLOW PATTERN. THIS WILL ALLOW FOR A PERIOD OF WAA GOING INTO WEDNESDAY WITH TEMPS REBOUNDING BACK INTO THE 70S FOR MOST LOCATIONS. MADE MINIMAL CHANGES TO GOING FORECAST HIGHS ON WEDNESDAY AS UNCERTAINTY WITH APPROACHING MID/HIGH LEVEL CLOUD COVER COULD PLAY INTO THE EXTENT OF WARMING THAT OCCURS. THE BEST WAA/MOIST ADVECTION WILL REMAIN JUST TO THE WEST FOR MOST OF THE DAY WEDNESDAY BUT THIS WILL CHANGE WEDNESDAY NIGHT AS MID/UPPER LEVEL TROUGH DIGS ACROSS THE CENTRAL PLAINS...AND STRENGTHENING LLJ BECOMES ORIENTED TOWARDS NORTHERN ILLINOIS. THIS COINCIDING WITH FAIRLY ENERGETIC MID LEVEL FLOW...DEVELOPING PRECIP SHIELD SHOULD BEGIN REACHING MOST LOCATIONS IN NORTHERN ILLINOIS AFTER THE MIDNIGHT TIME FRAME. DESPITE INCREASING INSTABILITY WEDNESDAY NIGHT...INSTABILITY AXIS DOES APPEAR TO STAY JUST TO THE WEST/SOUTHWEST OF THE CWA DURING THIS TIME. ALTHOUGH THIS MAY BE THE CASE...STRENGTHENING LLJ COULD OFFSET ANY LACKING INSTABILITY AND SO HAVE MAINTAINED CHANCE THUNDER WORDING OVER THE ENTIRE CWA...WITH THE FAR WEST AND SOUTHWEST AREAS LIKELY OBSERVING BEST CHANCES FOR THUNDER. MOISTURE WILL CONTINUE TO INCREASE DURING THIS TIME AND DO FEEL THERE COULD BE SOME PERIODS OF MORE MODERATE RAINFALL...BUT THIS WONT LIKELY OCCUR UNTIL VERY LATE IN THE NIGHT AND TOWARDS EARLY THURSDAY MORNING. BETTER AGREEMENT OBSERVED WITH VARYING MODELS THIS MORNING REGARDING APPROACHING MID/UPPER LEVEL TROUGH AND ASSOCIATED SURFACE FEATURE THURSDAY AND THURSDAY NIGHT. SURFACE LOW SHOULD LIFT RIGHT ALONG THE MISSISSIPPI RIVER AREA INTO SOUTHWEST WISCONSIN THURSDAY AND THEN INTO THE GREAT LAKES REGION THURSDAY NIGHT. CONTINUED LARGE SCALE SUPPORT DURING THIS PERIOD WILL ALLOW FOR A WET DAY THURSDAY INTO THURSDAY NIGHT AS PERIODS OF SHOWERS AND THUNDERSTORMS ARE LIKELY. A SLOWER DEPARTING TREND WILL OCCUR THURSDAY NIGHT...AND DID KEEP LIKELY WORDING LONGER INTO THE NIGHT. ALTHOUGH MOISTURE AND INSTABILITY WILL CONTINUE TO INCREASE DURING THIS TIME...IT DOES LOOK LIKE THE BEST INSTABILITY WILL REMAIN SOUTH OF THE CWA. SO AT THIS TIME...AM NOT OVERLY CONCERNED WITH ANY SEVERE POTENTIAL BUT AM MORE CONCERNED WITH HEAVY RAINFALL AND POSSIBLE LOCALIZED FLOODING...ESPECIALLY AS THE BEST OVERALL MOIST ADVECTION OCCURS INTO THURSDAY NIGHT. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CIGS AROUND 1000 FT CONTINUING THROUGH THE OVERNIGHT WITH OCCASIONAL LOWERING TO 800-900 FT...ESPECIALLY AT ORD. * MVFR CIGS EXPECTED TO CONTINUE INTO THE EVENING WITH LIFTING DURING THE AFTERNOON. * NORTHEAST WINDS WILL DIMINISH LATE TONIGHT AND REMAIN NEAR 10 KT THIS AFTERNOON. MDB //DISCUSSION...UPDATED 06Z... LOW MVFR CIGS CONTINUE TO BE SPREAD ACROSS THE THE TERMINALS AND WILL REMAIN IN PLACE OVERNIGHT. SOME PERIODIC LOWERING TO IFR WILL LIKELY OCCUR BUT CIGS UPSTREAM HAVE IMPROVED SLIGHTLY IN SPOTS LIKELY BECAUSE OF AN INFLUX OF DRIER AIR. EXPECT THAT THE LOWEST CIGS MAY BE OCCURRING NOW THROUGH THE NEXT FEW HOURS THEN MAY START TO LIFT TOWARDS DAYBREAK...WITH STEADIER LIFTING THROUGH THE MORNING. AM THINKING THAT RFD/DPA MAY SCATTER DURING THE AFTERNOON AT SOME POINT WITH FLOW OFF THE LAKE KEEPING CLOUD COVER BROKEN AT ORD/MDW/GYY THOUGH SOME SCATTERING COULD OCCUR. LOW LEVEL FLOW AT CLOUD LEVEL TURNS SOUTHEASTERLY THIS EVENING WHICH MAY PROMOTE AN INCREASE IN CLOUD COVER AS WELL AS PUSH IT FURTHER INLAND. THEREFORE A RETURN TO MVFR CIGS IS POSSIBLE AT DPA/RFD THIS EVENING. WILL KEEP COVERAGE SCATTERED FOR NOW. NORTHEAST SURFACE WINDS WILL BE GRADUALLY EASING THROUGH THE REST OF THE NIGHT AND GENERALLY BE NEAR 10 KT FOR THE MORNING/AFTERNOON BEFORE TURNING EAST THIS EVENING. MDB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN CIGS HOVERING AROUND 1000 FT OVERNIGHT. MEDIUM CONFIDENCE IN OCCASIONAL LOWERING BELOW 1000 FT...ESPECIALLY AT ORD. * MEDIUM-HIGH CONFIDENCE IN MVFR CONTINUING THROUGH THE DAY...HIGH CONFIDENCE IN BASES LIFTING DURING THE AFTERNOON. SCATTERING IS POSSIBLE. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY...VFR. SOUTHEAST WINDS. THURSDAY...TSRA LIKELY...MVFR POSSIBLE. SOUTH WINDS TURNING SOUTHWEST LATE. FRIDAY...SLIGHT CHANCE SHRA...MVFR POSSIBLE. BREEZY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...SLIGHT CHANCE SHRA. WEST-SOUTHWEST WINDS. RATZER && .MARINE... 257 AM CDT STRONG NORTHERLY WINDS WILL GRADUALLY DECREASE IN SPEED INTO THE AFTERNOON AS HIGH PRESSURE RIDGING MOVES ACROSS LAKE MICHIGAN. THE PRESSURE GRADIENT WILL TIGHTEN UP SOMEWHAT WEDNESDAY AS THE RIDGE SHIFTS EAST AND LOW PRESSURE OVER THE CENTRAL HIGH PLAINS TRACKS NORTH TO MANITOBA BY WEDNESDAY AFTERNOON. THIS WILL ALLOW WINDS TO SHIFT TO THE SOUTHEAST TONIGHT. WILL CONTINUE WITH THE SMALL CRAFT ADVISORY THROUGH THIS AFTERNOON. STEADY SOUTH TO SOUTHEAST WINDS WILL CONTINUE INTO THURSDAY WHEN LOW PRESSURE DEVELOPS OVER THE TEXAS/OKLAHOMA PANHANDLE AND TRACKS NORTHEAST TO THE U.P. OF MICHIGAN THURSDAY NIGHT. FORECAST MODELS HAVE STRUGGLED WITH THE TRACK AND INTENSITY OF THIS SYSTEM THOUGH THERE HAS BEEN VERY GENERAL AGREEMENT IN THE LOW TRACKING NORTHWEST OF THE LAKE AND DEEPENING WHILE DOING SO. WHILE SPECIFICS ARE STILL UNDETERMINED THE STAGE WILL BE SET FOR A PERIOD OF STRONGER WINDS ACROSS THE LAKE...STARTING OUT SOUTHERLY THEN TURNING WESTERLY AS A COLD FRONT PASSES THURSDAY NIGHT. SEVERAL OTHER MORE SUBTLE SURFACE TROUGHS MAY CROSS FRIDAY INTO SATURDAY ALLOWING WINDS TO FLUCTUATE BETWEEN WEST AND NORTHWEST. A PERIOD OF GALES STILL LOOKS POSSIBLE...PRIMARILY AFTER THE PASSAGE OF THE MAIN FRONT AS COLDER AIR SPREADS IN. WIND SPEEDS WILL GRADUALLY EASE GOING INTO SUNDAY. MDB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 313 AM CDT Tue Sep 30 2014 .SHORT TERM...(Today) ISSUED AT 312 AM CDT TUE SEP 30 2014 Short-term forecast concerns include potential for dense fog across the southern KILX CWA, as well as, approaching deck of low clouds across the north. Clear skies/light winds have once again led to the development of fog early this morning, particularly from the Saint Louis area eastward across southern Illinois. HRRR shows fog becoming dense across this area over the next few hours before dissipating after 8am. So far the fog has not become widespread or dense, but based on forecast soundings and the HRRR, have included patchy dense fog south of I-70. Have also issued a Special Weather Statement to highlight the low visbys. 07z/2am surface analysis shows cold front settling southward into central Illinois, with a widespread area of low clouds noted to the north of the boundary across the Great Lakes into north-central Illinois. Latest IR satellite imagery shows leading edge of clouds along the I-74 corridor. Main questions today will be how far south these clouds will push and whether or not they will clear out this afternoon. Satellite timing tools suggest the clouds will reach a Rushville to Mattoon line by daybreak, but additional southward progress appears unlikely as frontal boundary stalls. Will therefore go with a cloudy forecast across the northern two-thirds of the CWA this morning, with mostly sunny skies across the far south. Despite continued northeasterly flow behind the front, forecast soundings indicate a gradual dissipation of low-level moisture as the day progresses. Have gone with decreasing clouds through the afternoon accordingly. Due to the cloud cover and shift in wind direction, temps will be quite a bit cooler today than in recent days, with afternoon highs ranging from the upper 60s along/north of I-74 to around 80 far south. && .LONG TERM...(Tonight through Monday) ISSUED AT 312 AM CDT TUE SEP 30 2014 Winds will veer to the southeast on Wednesday in response to an approaching upper wave and its associated cold front. As a result, temperatures will rise back into the upper 70s and lower 80s. As a deep upper trough slowly approaches from the west, surface low pressure is expected to develop over the Southern Plains on Wednesday then lift northward into the Great Lakes by Thursday night. Warm-advection showers/thunder will develop ahead of this system Wednesday night: however, all model guidance keeps any precip focused mainly across the western half of the CWA. Given this slowing trend, have removed PoPs for all locations along/east of a Paris to Effingham line. Further west, will go with likely PoPs across the Illinois River Valley after midnight. As surface low deepens and tracks just west of the area on Thursday, strong S/SW flow will provide one more very warm day with highs in the upper 70s/lower 80s. Showers and thunderstorms will develop in advance of a slowly approaching cold front, mainly focused across the west. With strong upper dynamics in place and increasing amounts of moisture flowing northward from the Gulf of Mexico, a few strong to severe thunderstorms will be possible Thursday afternoon across west-central Illinois. Once low lifts into the Great Lakes, front will get a solid push eastward by Thursday evening. Will go with categorical PoPs across the board as the boundary interacts with a moist and moderately unstable environment. Cold front will push into Indiana by early Friday morning, with perhaps a few lingering showers across the Wabash River Valley. Main weather story late in the week will be the sharply cooler conditions. 850mb temps are progged to drop into the 0 to -2C range by Saturday morning, supporting daytime highs only in the lower to middle 60s and overnight lows in the lower 40s this weekend. Airmass will slowly moderate by early next week, with temperatures climbing back to around 70 by Monday. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1110 PM CDT MON SEP 29 2014 Cold front has just passed Pontiac and continues to make steady progress south-southwest into our forecast area. Based on the present movement, it appears it will push across PIA and BMI between 05-06z with our southern TAF sites seeing FROPA in the 08z-10z time frame. Winds initially after frontal passage will gust up to 20 kts from the northeast (020-050) but will begin to diminish an hour or two after passage. Based on the latest satellite trends, the MVFR and local IFR cigs will follow within an hour of the wind shift with cigs in the 500-1000 foot range, especially at KBMI with even the possibility for a little drizzle and vsby restriction in fog for an hour or two as the lower clouds settle in. The real challenge will be how quickly the lower cigs are able to lift late tomorrow morning or early afternoon with the low level moisture trapped under a developing subsidence inversion. Latest guidance off the NAM-WRF and HRRR continues to suggest we will see some breaks develop by late morning or early afternoon so will continue with the previous trends in the TAFs in scattering out the lower cigs by afternoon with some broken VFR cigs into the late afternoon hours. Ahead of the front, surface winds will be light and variable and then switch into the northeast after frontal passage with speeds in the 10 to 15 kts with a few gusts around 20 kts for a brief time. Winds on Tuesday will be from the northeast at 8 to 15 kts. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Smith
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
100 AM CDT TUE SEP 30 2014 .DISCUSSION... 230 PM CDT OUR STRETCH OF ONE WEEK OF ABOVE NORMAL TEMPERATURES IS ABOUT TO GET A TOUCH OF EARLY AUTUMN REALITY...AND A MUCH RUDER PUNCH LATE IN THE WEEK. FORECAST CONCERNS WERE ON THE TEMPERATURE DROP LATE THIS AFTERNOON INTO THE EVE AND SUBSEQUENT LIGHT RAIN/DRIZZLE CHANCES...THEN CLOUD COVER TUESDAY WHICH COULD GREATLY HINDER WARMING...AND FINALLY THE STORM SYSTEM WEDNESDAY NIGHT THROUGH FRIDAY BRINGING WIDESPREAD SHOWER AND STORM CHANCES. LATE THIS AFTERNOON INTO TONIGHT... OBSERVATIONS...SATELLITE...AND MKE RADAR ALL HAVE A GOOD HANDLE ON THE SHARP COLD FRONT DROPPING SOUTHWARD ACROSS THE GREAT LAKES REGION THIS AFTERNOON. OBSERVATIONS IN EAST CENTRAL WI HAVE DROPPED BY AS MUCH AS 23 DEGREES IN AN HOUR EARLY THIS AFTERNOON WITH THE SYNOPTIC AND LAKE-ENHANCED COOL SURGE. WHILE PRESSURE RISES WILL EASE BEHIND THE FRONT DUE TO THE PARENT LOW WELL OFF TO THE NORTHEAST...THIS FRONT SHOULD STILL COME BARRELING INTO NORTHEAST IL BY 530-630 PM WITH SOME GUSTS TO NEAR 30 MPH AND A 20-25 DEGREE TEMPERATURE DROP IN TWO-THREE HOURS. THIS FRONT WILL THEN CONTINUE TO MOVE SOUTHWARD THROUGH THE FORECAST AREA EASING SOME IN BAROCLINICITY. ANAFRONTAL FORCING IS SUPPORTING SCATTERED SHOWERS ACROSS CENTRAL WI. THIS MID-LEVEL FRONTOGENESIS AND OMEGA WILL DIMINISH SOME AS THIS FRONT SLIDES INTO OUR AREA AND SOUNDINGS SUPPORT MORE OF LIGHT RAIN OR DRIZZLE IF PRECIPITATION CAN OCCUR. THIS SEEMS MOST FAVORED IN THE MID-LATE EVE OVER NORTHERN IL AND POSSIBLY REACHING INTO FAR NORTHWEST INDIANA. CLOUDS SHOULD BECOME WIDESPREAD AS VISIBLE SATELLITE SHOWS UPSTREAM AND THE SLOWING BOUNDARY TRAPS THE MOISTURE BENEATH A STRENGTHENING INVERSION. TUESDAY... SURFACE RIDGING WILL POKE INTO THE WESTERN GREAT LAKES DURING THIS TIME...BUT THROUGH EARLY AFTERNOON NORTHEAST LOW-LEVEL FLOW SHOULD CONTINUE OVER THE AREA. CONCEPTUALLY IN A STRONG POST-FRONTAL AIR MASS WITH A STRONG INVERSION IN PLACE...THINK STRATUS WILL CONTINUE THROUGH AT LEAST EARLY AFTERNOON IF NOT THE ENTIRE DAY ESPECIALLY FOR LAKE ADJACENT AREAS. HAVE EXTENDED THE DURATION OF FORECAST CLOUD COVER CONSIDERABLY AND HAVE CORRELATED TEMPERATURES DOWNWARD...WITH THE MERCURY ONLY RISING A HANDFUL OF DEGREES IN NEAR-LAKE AREAS INCLUDING CHICAGO. FURTHER SOUTH AND WEST...MID 60S MAY BE REALIZED. INCREASING SUBSIDENCE IN THE AFTERNOON SHOULD HELP TO OPEN SOME HOLES IN THE CLOUDS. LATTER HALF OF THE WEEK AND NEXT WEEKEND... NORTHERN HEMISPHERIC WATER VAPOR SHOWS AN ACTIVE PATTERN OVER THE WESTERN U.S. INTO THE NORTHERN PACIFIC AND THIS WILL EVOLVE OVER OUR REGION DURING THIS PERIOD. PHASING OF THE CURRENT WESTERN U.S. UPPER LOW AND A TROUGH MOVING ONSHORE OF WESTERN CANADA IS LIKELY ONE CULPRIT TO FAIRLY SUBSTANTIAL MODEL DIFFERENCES OVER OUR REGION. HAVE LEANED TOWARD THE MORE CONSISTENT GFS OUTPUT FOR THIS TIME WITH CONFIDENCE BEING ESPECIALLY LOW SATURDAY-MONDAY. SOUTHERLY FLOW WILL DEVELOP BACK INTO THE AREA WEDNESDAY AND THURSDAY IN RESPONSE TO MULTIPLE ROUNDS OF CYCLOGENESIS. THIS LOOKS TO YIELD HIGHS IN THE 70S THOUGH WITH HIGHS ON THURSDAY DEPENDENT ON RAIN COVERAGE. THE RAIN CHANCES LOOK TO INCREASE LATER WEDNESDAY NIGHT AND THROUGH THURSDAY AS DEEP LAYER MOISTURE CONVERGENCE INCREASES WITHIN BETTER SUPPORT AND FOCUS FOR ASCENT. WHILE SPECIFICS ON EXACT PRECIP EVOLUTION REMAIN UNCERTAIN ALONG WITH WHICH PERIOD WITHIN 24-36H WINDOW WILL HAVE THE MOST WIDESPREAD COVERAGE...CONTINUE THE BROAD LIKELY POPS MENTION. WOULD EXPECT TO SEE SOME THUNDER WITH SUCH A DEEPENING SYSTEM ON THURSDAY AFTERNOON INTO THE NIGHT AND A RIBBON OF INSTABILITY AHEAD OF THE INCOMING COLD FRONT. WHILE THERE IS AT LEAST AN ISOLATED SEVERE WEATHER POTENTIAL IN THE OVERALL REGION...IT WOULD SEEM TO BE BETTER OVER THE MID-MISSISSIPPI VALLEY TO OUR SOUTH WITH MOISTURE TRANSPORT/DEEPER INSTABILITY POTENTIALLY INHIBITED TO REACH THIS FAR NORTH FROM CONVECTION OVER THE AREA. MODELS SHOW WIDESPREAD DIFFERENCES BEHIND THIS SYSTEM IN AN UNSETTLED NORTHWEST FLOW. THE GFS IS NOT AS PRONOUNCED WITH THE COLD AIR INCOMING ON FRIDAY/FRIDAY NIGHT AND LEANING THAT ROUTE STILL PROVIDES LOWS IN THE UPPER 30S-MID 40S ACROSS MOST OF THE AREA FRIDAY/SATURDAY/SUNDAY NIGHTS...ALTHOUGH THERE WILL CERTAINLY BE SOME DEPENDENCY ON CLOUD COVER. FRIDAY LOOKS WINDY THOUGH MAINLY DRY WITH SUBSIDENCE BEHIND THE AFOREMENTIONED SYSTEM. WEEKEND CHANCES OF RAIN ARE TOUGH TO SAY AND DEPENDENT ON WHEN A CLEARER PICTURE IS PAINTED WITH NORTHWEST FLOW DISTURBANCES. MTF && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 06Z... * CIGS AROUND 1000 FT CONTINUING THROUGH THE OVERNIGHT WITH OCCASIONAL LOWERING TO 800-900 FT...ESPECIALLY AT ORD. * MVFR CIGS EXPECTED TO CONTINUE INTO THE EVENING WITH LIFTING DURING THE AFTERNOON. * NORTHEAST WINDS WILL DIMINISH LATE TONIGHT AND REMAIN NEAR 10 KT THIS AFTERNOON. MDB //DISCUSSION...UPDATED 06Z... LOW MVFR CIGS CONTINUE TO BE SPREAD ACROSS THE THE TERMINALS AND WILL REMAIN IN PLACE OVERNIGHT. SOME PERIODIC LOWERING TO IFR WILL LIKELY OCCUR BUT CIGS UPSTREAM HAVE IMPROVED SLIGHTLY IN SPOTS LIKELY BECAUSE OF AN INFLUX OF DRIER AIR. EXPECT THAT THE LOWEST CIGS MAY BE OCCURRING NOW THROUGH THE NEXT FEW HOURS THEN MAY START TO LIFT TOWARDS DAYBREAK...WITH STEADIER LIFTING THROUGH THE MORNING. AM THINKING THAT RFD/DPA MAY SCATTER DURING THE AFTERNOON AT SOME POINT WITH FLOW OFF THE LAKE KEEPING CLOUD COVER BROKEN AT ORD/MDW/GYY THOUGH SOME SCATTERING COULD OCCUR. LOW LEVEL FLOW AT CLOUD LEVEL TURNS SOUTHEASTERLY THIS EVENING WHICH MAY PROMOTE AN INCREASE IN CLOUD COVER AS WELL AS PUSH IT FURTHER INLAND. THEREFORE A RETURN TO MVFR CIGS IS POSSIBLE AT DPA/RFD THIS EVENING. WILL KEEP COVERAGE SCATTERED FOR NOW. NORTHEAST SURFACE WINDS WILL BE GRADUALLY EASING THROUGH THE REST OF THE NIGHT AND GENERALLY BE NEAR 10 KT FOR THE MORNING/AFTERNOON BEFORE TURNING EAST THIS EVENING. MDB //ORD AND MDW CONFIDENCE...UPDATED 06Z... * HIGH CONFIDENCE IN CIGS HOVERING AROUND 1000 FT OVERNIGHT. MEDIUM CONFIDENCE IN OCCASIONAL LOWERING BELOW 1000 FT...ESPECIALLY AT ORD. * MEDIUM-HIGH CONFIDENCE IN MVFR CONTINUING THROUGH THE DAY...HIGH CONFIDENCE IN BASES LIFTING DURING THE AFTERNOON. SCATTERING IS POSSIBLE. * HIGH CONFIDENCE IN WIND TRENDS. MDB //OUTLOOK FOR ORD/MDW FOR 12Z WEDNESDAY-12Z MONDAY...UPDATED 00Z... WEDNESDAY...VFR. SOUTHEAST WINDS. THURSDAY...TSRA LIKELY...MVFR POSSIBLE. SOUTH WINDS TURNING SOUTHWEST LATE. FRIDAY...SLIGHT CHANCE SHRA...MVFR POSSIBLE. BREEZY WEST WINDS. SATURDAY...VFR. WEST WINDS. SUNDAY...SLIGHT CHANCE SHRA. WEST-SOUTHWEST WINDS. RATZER && .MARINE... 305 PM CDT A SHARP COLD FRONT IS MARCHING DOWN THE LAKE THIS AFTERNOON WITH A WIND SHIFT TO NORTH- NORTHEASTERLY BEHIND THE FRONT. THE FRONT HAS ALREADY PASSED THROUGH MILWAUKEE AS OF 300 PM CDT. OBSERVATIONS BEHIND THE FRONT HAVE HELD AT 30 KT OR LESS...SO FEEL CONFIDENT THAT WINDS WILL GENERALLY REMAIN SUB- GALE THROUGH THIS COLD FRONT PASSAGE AS THE PRESSURE GRADIENT WILL WEAKEN SOMEWHAT AS THE FRONT PUSHES SOUTH. THERE COULD BE A FEW GUSTS ABOVE 30 KT WITH THE FRONTAL PASSAGE. EXPECT WAVES TO BUILD THROUGH TUESDAY AS WE REMAIN UNDER NORTH FLOW THROUGH THE DAY...WITH THE HIGHEST WAVES ON SOUTHERN PORTIONS OF THE LAKE. HIGH PRESSURE OVER SOUTHERN ONTARIO WILL WEAKEN AND SLOWLY SHIFT EAST WHILE THE RIDGE AXIS ASSOCIATED WITH IT WILL SHIFT OVER THE LAKE TOMORROW AFTERNOON...THEN MOVE EAST OF THE LAKE ON WEDNESDAY. AS THIS OCCURS ADDITIONAL LOWS IN THE PLAINS WILL LEAD TO A TIGHTENING PRESSURE GRADIENT LATER WEDNESDAY INTO THURSDAY. AT THIS POINT THE STRONGER LOW HEADS NORTH THROUGH MANITOBA WHILE ANOTHER LOW MOVES OVER THE LAKE ON THURSDAY NIGHT. GUIDANCE STILL REMAINS MIXED AS TO WHETHER THIS LOW WILL BE IN A DEEPENING PHASE AS IT TRANSITS THE LAKE OR IF IT WILL INTENSIFY MORE SO NORTH AND EAST OF LAKE MICHIGAN. A STRONG COLD FRONT WILL THEN MOVE THROUGH LATER THURSDAY NIGHT INTO FRIDAY BRINGING GUSTY NORTHWESTERLY WINDS. IF THE LOW IS STRONGER...THERE COULD BE GALES IN THE BETTER MIXED ATMOSPHERE BEHIND THE LOW FRIDAY. KMD && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 7 PM TUESDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1114 PM CDT Mon Sep 29 2014 .UPDATE... ISSUED AT 852 PM CDT MON SEP 29 2014 The cold front has slipped south of Joliet over the past hour and continues to make steady progress towards our area this evening. Not much in the way of weather other than a wind shift and an increase in clouds. Based on the present movement, it appears the boundary will shift south thru Peoria and Bloomington between Midnight and 2 am. Radar mosaic showing a decreasing area of showers north of the boundary, so not expecting any measureable precip with the front, other than the possibility for a brief period of drizzle as the low clouds settle south into the forecast area after midnight. Other than some adjustments to the evening temperature trends, no other changes were needed to the grids that would require an evening update. && .SHORT TERM...(Tonight) ISSUED AT 321 PM CDT MON SEP 29 2014 Weak high pressure will continue fair weather into this evening as few to scattered cumulus clouds with 5-7k ft bases away from the IN dissipate around sunset. Patchy shallow ground fog will develop again near rivers and streams in southeast IL during overnight. A cold front over southeast WI and central IA will push south into central IL overnight, reaching I-70 by sunrise Tue, and weaken over southeast IL on Tuesday. Stratus clouds behind/north of the front will move south into central IL during overnight and especially affect areas from I-74 north while southeast IL likely stays clear most of tonight. Light winds into this evening will become northeast at 5 to 10 mph during overnight over central IL. Lows tonight will mostly be in the mid 50s with lower 50s north of Peoria. && .LONG TERM...(Tuesday through Monday) ISSUED AT 321 PM CDT MON SEP 29 2014 A dry front, located just north of the state is forecast to slowly drop into the area tonight through tomorrow. NAM-WRF model has been consistent with forecasting an increase in low clouds across the northern half of the state tonight and tomorrow. It looks like it could get to I-74 by morning and could progress further south tomorrow. How far south it gets will depend on how much of the southern edge of the cloud deck gets eroded away by the strong sun during the day tomorrow. So, current thinking is it sill get past I-74 and could get to I-72 in the eastern part of the CWA. During the day tomorrow, the sunshine should dissipate a lot of the clouds, like what is occurring in parts of SD/MN/and IA today. Then mostly clear and dry conditions are expected tomorrow night through Wed. A weather system in the western US will the lift northeast into the northern plains and will have a trailing cold front that will extend down into the southern plains. Showers and thunderstorms are expected to develop along and ahead of this front Wed well west of the CWA. However, these storms will advect eastward into the state beginning Wed night. A second low pressure area will develop along the front and will move northeast into the Midwest and bring the cold front through the area Thur and Thur night. Additional thunderstorms will develop along the front Thursday and move across the area during the day and through Thur night. Conditions do not look right for any of the storms to produce severe weather, but this could change in the next couple of days. However, lightning and brief heavy rainfall will be likely with any storms that move through the area late Wed night and Thursday. Once the front and pcpn pass, there could be some lingering showers behind the front, so will be keeping some chance pops in the east for Friday. Beyond Friday, conditions will improve as a drier and cooler air mass pushes into the area for the weekend. There is one small, weak wave that could bring some light showers to the northeastern parts of the area, along and north of I-74, but its too far away to have much confidence, so will just have slight chance pops for Sunday, which will not be mentioned in the worded forecast. Temps will remain above normal tomorrow, when the sunshine is able to break through the clouds, and Wed as well. Then clouds and rain for Thur will keep temps milder and around normal. Once the front moves through at the end of the week, temps will become much cooler and actually be below normal for the beginning of Oct. && .AVIATION...(For the 06Z TAFS through 06Z Tuesday night) ISSUED AT 1110 PM CDT MON SEP 29 2014 Cold front has just passed Pontiac and continues to make steady progress south-southwest into our forecast area. Based on the present movement, it appears it will push across PIA and BMI between 05-06z with our southern TAF sites seeing FROPA in the 08z-10z time frame. Winds initially after frontal passage will gust up to 20 kts from the northeast (020-050) but will begin to diminish an hour or two after passage. Based on the latest satellite trends, the MVFR and local IFR cigs will follow within an hour of the wind shift with cigs in the 500-1000 foot range, especially at KBMI with even the possibility for a little drizzle and vsby restriction in fog for an hour or two as the lower clouds settle in. The real challenge will be how quickly the lower cigs are able to lift late tomorrow morning or early afternoon with the low level moisture trapped under a developing subsidence inversion. Latest guidance off the NAM-WRF and HRRR continues to suggest we will see some breaks develop by late morning or early afternoon so will continue with the previous trends in the TAFs in scattering out the lower cigs by afternoon with some broken VFR cigs into the late afternoon hours. Ahead of the front, surface winds will be light and variable and then switch into the northeast after frontal passage with speeds in the 10 to 15 kts with a few gusts around 20 kts for a brief time. Winds on Tuesday will be from the northeast at 8 to 15 kts. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Smith SHORT TERM...07 LONG TERM...Auten AVIATION...Smith
AREA FORECAST DISCUSSION
NWS DES MOINES IA
627 AM CDT TUE SEP 30 2014 ...UPDATED AVIATION DISCUSSION... .SHORT TERM /TODAY/... ISSUED AT 336 AM CDT TUE SEP 30 2014 .TODAY...FORECAST CONCERNS DEALT WITH TIMING OF PRECIP AND MAX TEMPERATURES TODAY. LARGE AND STUBBORN 500 MB RIDGE WILL SLOW THE EASTWARD MOVING OF THE INCOMING 500MB VORT MAX/LOW PRESSURE SYSTEM INTO THE STATE UNTIL LATE THIS AFTERNOON. THE HRRR/HOPWRF/ARW/NAM12 ALL KEEP PRECIP OUT OF WESTERN IOWA UNTIL AFTER 18-19Z TODAY AND THEN INTO THE FORECAST AREA BY AROUND 21-22Z TIME FRAME. CUT BACK ON THE EASTERN EXTENT OF POPS AS WELL AS LOWERED POPS TO CHANCES UNTIL AFTER 20Z ACROSS THE FAR WEST. NAM/GFS/RAP CRL SOUNDING HAVE RAIN FALLING B/T 20-23Z DEPENDING THE MODEL. PLUS THE STRONG MOISTURE TRANSPORT AND THETA-E ADVECTION FINALLY ENTER THE WESTERN PORTION OF THE FORECAST AREA MID TO LATE AFTERNOON. HIGHER CONFIDENCE WITH THE DELAYED ONSET OF PRECIP TODAY. MAX TEMPS WERE TRICKY TODAY WITH THE LESSER EASTWARD EXTENT OF PRECIP BUT STILL ANTICIPATING AN ABUNDANCE OF MID TO HIGH CLOUD COVER THROUGH MUCH OF THE DAY. THE PARTIAL STRONG WAA AS SOUTHEAST FLOW INCREASES THROUGHOUT THE DAY SHOULD HELP WARM TEMPS IN THE CENTRAL TO SOUTH INTO THE MID-UPPER 70S. LEANED TOWARD THE ECMWF FOR TEMPERATURES TODAY. NAM SEEMED WAY TOO COLD BUT THE GFS WAS MORE IN LINE WITH THE ECMWF FOR TEMPERATURES. .LONG TERM /TONIGHT THROUGH MONDAY/... ISSUED AT 336 AM CDT TUE SEP 30 2014 ACTIVE WEATHER PATTERN RETURNING TO THE AREA AFTER RATHER QUIESCENT PERIOD. FOR NOW H500 RIDGE REMAINS DOMINANT ACROSS THE CENTRAL CONUS WITH LARGE SFC HIGH ANCHORED OVER SOUTHERN CANADA JUST NORTH OF LAKE SUPERIOR. SUBJECTIVE H500 ANALYSIS AT 00Z SHOWS WEAK LOBE OF HT FALLS MOVING ACROSS WESTERN IA AND EASTERN NE ASSOCIATED WITH FIRST LOBE OF VORTICITY MOVING NORTHEAST OUT OF THE CENTRAL ROCKIES. MAIN UPPER LOW CONTINUES TO DRIFT NNE OUT OF CENTRAL CO WITH SFC SHORTWAVE OVER NORTHEAST COLORADO WITH ATTENDANT TROUGH BACK NORTHWEST INTO CENTRAL WY. BY 00Z WED...THE H500 SHORT WAVE WILL CONTINUE TO MOVE NORTH NORTHEAST WHILE THE H500 VORTICITY MAX OVER NEBRASKA INTERACTS WITH A RIBBON OF H850 MOISTURE EXTENDING FROM THE DAKOTAS SOUTH TO TEXAS. THIS SHOULD SLOWLY INCREASE THUNDER CHANCES ACROSS NEBRASKA TODAY WITH SOME ACTIVITY REACHING THE WESTERN HALF OF THE FORECAST AREA TOWARD 00Z. THE ADVANCEMENT OF THE BAND OF SHOWERS AND STORMS WILL BE COMPLICATED SOMEWHAT BY THE UPPER LEVEL RIDGE AND WEAK OMEGA BLOCK ACROSS THE CENTRAL CONUS. ALONG WITH THAT...REINFORCING DRY AIR CONTINUES TO ADVECT SOUTHWEST AT THE SFC FROM THE EASTERN GREAT LAKES TOWARD IOWA WHERE DEW POINTS OF THE MID 40S FROM EASTERN WISCONSIN GIVE WAY TO DEW POINTS IN THE MID 50S TO LOWER 60S ACROSS WESTERN IOWA. CURRENT TRENDS AND MODEL GUIDANCE SUGGEST THAT THE PRECIPITATION SHOULD SLOWLY WORK EAST OVERNIGHT AS THE DRY AIR AND PERSISTENT NORTHEAST FLOW TODAY GRADUALLY BECOME MORE SOUTHEAST WITH WED MORNING. HAVE TRIMMED BACK EARLY PERIOD POP AFT 00Z THIS EVENING AND INCREASED OVERNIGHT MORE IN LINE WITH 12Z/00Z EURO BASED ON ANALYSIS AND CURRENT TRENDS. ALL MODELS CONTINUE TO INDICATE LESSENING INSTABILITY AS THE AREA OF STORMS CROSSES THE REGION TONIGHT. SO...HAVE TRIMMED BACK WORDING FROM CAT THUNDER TO SCT THUNDER AND THEN ISO AFT 04Z TONIGHT WEST. SINCE THIS IS A SEVERAL PART SYSTEM WITH THE SECOND WAVE PROJECTED TO CROSS THE AREA ON WEDNESDAY...POP CHANCES WILL AGAIN INCREASE OVER THE WEST/CENTRAL AREAS EARLY AND THEN EAST THROUGH THE DAY WITH HIGHER POPS EXPECTED. ONCE AGAIN WITH SOMEWHAT LIMITED INSTABILITY THUNDER OF THE ISO TO SCT VARIETY IS EXPECTED. WITH THE SLOWER EVOLUTION OF THE ENTIRE SYSTEM AND THE SYNOPTIC SCALE MODELS SUGGESTING THE WESTERN MOST WAVE...NOW OVER NORTHWEST BRITISH COLUMBIA...WILL HAVE A LONGER TIME TO DIG SOUTHEAST THROUGH WEDNESDAY...AND SHOULD TRACK THROUGH IOWA THURSDAY AND THURSDAY EVENING. THIS SHOULD REDUCE POP CHANCES WED EVENING AND OVERNIGHT EXCEPT FOR THE SOUTH. THE CURRENT 00Z GEM IS FOLLOWING THE EARLIER 12Z EURO EVOLUTION WHILE THE NAM IS WOEFULLY TOO FAR NORTH WITH ITS FORCING WED NIGHT AND THURSDAY. THE GFS LIES INBETWEEN...BUT IS LEANING MORE TOWARD THE 00Z GEM AND 12Z EURO SOLUTIONS. GIVEN OUR SHIFT TO NORTHWEST FLOW AND MORE ENERGETIC FALL SYSTEMS...PREFERENCE WILL BE GIVEN TO THE SLOWER SOLUTIONS THAT ARE DIGGING THIS SUBSEQUENT WAVE ACROSS THE CENTRAL CONUS. RAIN CHANCES SHOULD DIMINISH WEDNESDAY NIGHT INTO EARLY THURSDAY...ONLY TO INCREASE AGAIN AS THE FINAL WAVE DEEPENS OVER THE MID MISSISSIPPI RIVER VALLEY ON THURSDAY AND A DEVELOPING FULL FALL CYCLONE EMERGES. GIVEN THE POTENTIAL FOR A DEF ZONE RAIN AXIS OVER THE NORTHWEST AND THUNDERSTORMS OVER THE EAST/SOUTHEAST...WILL INCREASE RAIN AND THUNDER CHANCES ACCORDINGLY. OUTLOOK FOR SEVERE IS THE NEXT ITEM OF DISCUSSION...WE CONTINUE OUTLOOKED FOR A SLIGHT RISK ACROSS THE SOUTHWEST ON DAY2...BUT THIS IS PREDICATED ON A RATHER AMBITIOUS WARMING OF THE NAM SOLUTION IN THE AFTERNOON HOURS ACROSS MUCH OF THE CENTRAL PLAINS. GIVEN THE UNCERTAINTY OF HOW MUCH IF ANY SUN WE WILL HAVE DURING THE DAY WED...CONDITIONS REMAIN RATHER CONDITIONAL DURING THE DAY. AFTER SUNSET...POTENTIAL FOR SOME NOCTURNAL CONVECTION WHICH MAY LEAD TO WIND OR HAIL THREATS ACROSS THE FAR SOUTHWEST/SOUTH. WITH THE PASSAGE OF THE FALL CYCLONE THURSDAY AFTERNOON...TEMPS WILL BEGIN A SIGNIFICANT DOWNWARD TREND. H850 TEMPS ON FRIDAY WITH A CLOSED H500 LOW AMPLIFYING SOUTH INTO THE REGION LOWERS OUR DAYTIME H850 TEMPS TO 0 TO -2C. WITH -30C PROGGED AT H500...COLD POOL SHOULD CLOUD AREA OVER...PERHAPS BRINGING SHOWERS AND STRONGER MIXING ACROSS THE REGION AS WELL DURING THE DAYTIME HOURS. BY FRIDAY NIGHT AND EARLY SAT MORNING...COLD AIR SETTLES INTO THE AREA. FROST MAY BE POSSIBLE DEPENDING ON HOW QUICKLY THE WINDS DECOUPLE OVERNIGHT. FOR NOW SFC GRADIENT LOOKS STRONG ENOUGH TO SUPPORT SOME FLOW THROUGH SATURDAY MORNING. BY LATE SAT AFTERNOON EURO H850 TEMPS RECOVER TO 2C WEST TO -2C EAST. GFS IS TOO PROGRESSIVE AND WARMING TOO FAST. HIGHS SATURDAY WILL LIKELY SLOWLY RECOVER A FEW DEGREES TO THE MID TO UPPER 50S WITH A CRISP FALL DAY EXPECTED. A DECENT PUSH OF WARM AIR ADVECTION SUNDAY MORNING SHOULD BRING A FEW CLOUDS...AND A MILDER DAY WITH HIGHS BACK TOWARD 70. WITH WNW FLOW NOW PERSISTING INTO EARLY NEXT WEEK...EXPECT SOME FAST MOVING CLIPPERS TO TRACK THROUGH THE REGION...KEEPING TEMPS NEAR SEASONAL NORMS. && .AVIATION...30/12Z ISSUED AT 622 AM CDT TUE SEP 30 2014 IFR/LIFR CIGS WILL CONTINUE THROUGH MUCH OF THE MORNING. THE LATEST HRRR HAS THE LOW STRATUS BURNING OFF B/T 14-17Z THIS MORNING. PRESSURE GRADIENT WILL CONTINUE TO STRENGTHEN AND ALLOW FOR THE EAST-SOUTHEAST WINDS TO INCREASE THROUGH THE DAY. INTRODUCED MVFR CIGS THIS EVENING AND THEN PRECIP ROUGHLY 3-4 HOURS AFTER CIGS MOVE INTO CENTRAL IOWA. && .DMX WATCHES/WARNINGS/ADVISORIES...NONE. && $$ SHORT TERM...PODRAZIK LONG TERM...REV AVIATION...PODRAZIK
AREA FORECAST DISCUSSION...UPDATED
NWS TOPEKA KS
728 PM CDT Wed Oct 1 2014 ...Update to aviation forecast discussion... .SHORT TERM...(This Evening through Thursday) Issued at 320 PM CDT WED OCT 1 2014 Spring like conditions driving an early October forecast today as severe storms have developed over southeastern Kansas and west central Missouri. Earlier clouds and showers over eastern Kansas gave way to clearing early and then afternoon cumulus clouds as daytime heating ensued. Diffuse boundary / surface trof still appears to extend from near Newton Kansas northeast through Council Grove and into Wabaunsee county. Morning and afternoon soundings continue to show an unstable atmosphere, but low level winds in the surface trof have weakened through the day. Dewpoints near 70 continue to move northward into the counties south of the interstate. Conditional severe threat remains for east central Kansas. Lack of a strong forcing mechanism over our area makes forecast more difficult. However storms to the south have mid level energy moving into SE Kansas and NE Oklahoma, and hodographs going straight in the mid levels favor splits, with left movers approaching our south CWA edge at this time. Primary threat from these storms will be large hail and winds, although with outflow boundaries moving out of the southern and eastern storms, will need to watch for tornado threat as well. Worth mentioning these storms are producing considerable lightning and locally heavy rainfall. That said, the better conditions come together primarily for the counties along and SE of the turnpike where the watch is now in place. As the low level jet increases later this evening, may see additional strengthening if storms develop in south central Kansas and move into our southeast as the latest HRRR would suggest. .LONG TERM...(Thursday Night through Wednesday) Issued at 320 PM CDT WED OCT 1 2014 Main upper trough axis ejects eastward into the central plains on Thursday. The sfc low is progged to deepen through the day as it phases with the upper wave. Showers and thunderstorms from the overnight period will have made its way into north central KS by Thurs. morning. A decent 30 to 40 kt h85 jet may also support additional convection forming over east central KS. Through the day on Thursday, the main frontal boundary continues to trend more progressive in pushing east of the CWA by 00Z Friday. Dependent on mesoscale factors such as if and when morning convection in the east can clear out and where the boundary sets up by peak heating may form a few strong to severe storms in the late afternoon. Far eastern KS should see the best chances for severe weather with mainly high wind and large hail the primary hazards. Localized flooding may also pose a hazard for the entire area with an average of 0.5 to 2.5 inches of rainfall in the past 24 hours. Convection clears east Thursday evening as a stronger upper wave plunges southeast into the Great Lakes region. Strengthening mid and low level wind field pickup sfc speeds from the northwest between 20 and 25 mph sustained on Friday. Consensus operational guidance is hinting on a weak wave traversing through the mean flow across northeast Kansas on Friday. While model soundings do not show ample low level moisture, included a low end chance for showers. The main story through the weekend will be strong subsidence and cold air advection as highs fall Friday from the 70s to the 60s for Saturday. May need frost headlines for Saturday AM as trends with h85 temps continue to fall near 0C. Have lowered low temps down into the middle and lower 30s area wide. Extended period remains quiet and dry as northwest flow and blocking ridge holds over the western CONUS. Airmass modulates back with highs in the 70s and lows in the 50s. Another digging trough over the Great Lakes region may push weak embedded waves southward into the region on Wednesday where slight chances for precip were mentioned. && .AVIATION...(For the 00Z TAFs through 00Z Thursday Evening) Issued at 720 PM CDT WED OCT 1 2014 Scattered thunderstorms will affect the TAF sites for the next 2-3 hours before temporarily ending with the potential for another area of convection then aft 08z which could produce mvfr cigs and brief ifr vsbys in heavy rain. Winds will shift to the northwest and increase with mvfr stratus aft 19z as the cold front moves through the taf sites. && .TOP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...67 LONG TERM...Bowen AVIATION...63
AREA FORECAST DISCUSSION
NWS GOODLAND KS
538 PM MDT WED OCT 1 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 114 PM MDT WED OCT 1 2014 18Z WATER VAPOR IMAGERY/RAP ANALYSIS INDICATED STRONG TROUGH MOVING INTO NORTHERN COLORADO. AT THE SFC...FAIRLY DRY AIRMASS IN PLACE ACROSS THE TRI STATE AREA WITH FRONT DRAPED FROM KLBL TO KMCI. MAIN FORECAST CONCERN FOR THE PERIOD WILL CENTER AROUND APPROACHING SHORT WAVE TROUGH AND DEVELOPMENT OF PRECIPITATION AS IT MOVES INTO THE AREA. WHILE SEEING CURRENT DRY AIR IN THE AREA DOES CAUSE SOME CONCERN ON PRECIP DEVELOPMENT...BULK OF NEAR TERM MODELS ALL INDICATE A TAP OF MOISTURE ORIGINATING NEAR SFC FRONT AND INTERACTING WITH ELEVATED FRONTAL ZONE THIS EVENING. MIXING RATIOS IN THIS PLUME ARE HIGH AND WITH SOME ELEVATED INSTABILITY EXPECT A DECENT RESPONSE TO PERIOD OF STRONG FRONTOGENESIS. SOMEWHAT SURPRISED BY CONSISTENCY OF QPF OUTPUT FROM AVAILABLE DATA SOURCES AND AM COMFORTABLE INCREASING GENERAL AMOUNTS TO 0.25 TO 0.75 AT MOST LOCATIONS. CHOSE NOT TO GO ON THE HIGH END OF PRECIPITATION THOUGH...DUE TO AFOREMENTIONED CONCERNS OVER MOISTURE QUALITY. FORCING WILL DIMINISH TOWARDS SUNRISE AS DEEP CAA TAKES OVER. SURPRISINGLY...SOME LOW TOPPED INSTABILITY DOES EXIST THROUGH THE MORNING HOURS SO A FEW LINGERING SHOWERS APPEAR WARRANTED. OTHER CONCERN FOR THE NEAR TERM WILL BE WINDS BEHIND STRONG COLD FRONT ADVANCING ACROSS THE AREA TONIGHT. 12Z NAM AND TO A LESSER DEGREE THE RAP INDICATE STRONG 3 HR PRESSURE RISES IN EXCESS OF 6MB AS FRONT PASSES. THIS COULD LEAD TO A PERIOD OF NEAR ADVISORY LEVEL GUSTS FOR AN HOUR OR TWO BEHIND THE FRONT. PLAYED UP WINDS A BIT IN THE FORECAST...BUT UNTIL STRONG PRESSURE RISES/GUSTS BECOME MORE APPARENT IN OBSERVATIONAL DATA PLAN ON HOLDING OFF ON ANY HIGHLIGHTS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 149 PM MDT WED OCT 1 2014 THURSDAY NIGHT-FRIDAY NIGHT... A SECOND COLD FRONT WILL MOVE ACROSS THE REGION LATE THURSDAY NIGHT ALONG WITH FRONT END OF H3 JET ON BACK SIDE OF UPPER LEVEL TROUGH. WITH STRONG FRONTOGENETICAL AND UPPER LEVEL FORCING I DECIDED TO KEEP 20 POPS ACROSS NW PART OF CWA THURSDAY NIGHT DESPITE LIMITED MOISTURE PROFILES. STRONG PRESSURE RISES BEHIND THE FRONT SHOULD ALLOW A BRIEF PERIOD OF NEAR ADVISORY OR ADVISORY WINDS (45 MPH) AS PRESSURE GRADIENT TIGHTENS OVERNIGHT. NAM IN PARTICULAR SHOWS 6HR PRESSURE RISES IN EXCESS OF 10MB WHICH IS CONCERNING AND COULD INDICATE POSSIBILITY OF BRIEF WARNING CRITERIA WINDS. IF THERE IS VIRGA OR LIGHT SHOWERS THIS MAY ALSO HELP MIX STRONGER WINDS TO THE SURFACE. WILL HOLD OFF FOR NOW ON HEADLIGHTS...BUT THIS NEEDS TO BE MONITORED. GRADIENT RELAXES FROM THE WEST TO THE EAST AS UPPER LEVEL JET AND TROUGH AXIS MOVE EAST...HOWEVER THERE ARE STILL STRONG WINDS ALOFT OVER THE EASTERN CWA THROUGH THE DAY FRIDAY. PROFILES WOULD LIMIT MIXING TO BELOW WHERE STRONGEST WINDS ALOFT ARE FRIDAY DESPITE SUNNY CONDITIONS...SO ADVISORY LEVEL WINDS SEEM UNLIKELY DURING THE DAY FRIDAY. SHOULD STILL BE WINDY...ESPECIALLY FRIDAY AFTERNOON. VERY COOL AIR MASS SETTLES INTO REGION THURSDAY NIGHT AND FRIDAY. IF IT WASNT FOR INCREASING CLOUD COVER AND WINDY CONDITIONS THIS AIR MASS WOULD HAVE SUPPORTED A HARD FREEZE (LOOKS LIKE WELL LUCK OUT). CLEAR SKIES...LOW TD...AND LIGHT WINDS WILL SUPPORT GOOD RADIATIONAL CONDITIONS FRIDAY NIGHT. AT THE SAME TIME TEMPS ALOFT WILL BE MODERATING AS A RIDGE OVER THE SW US BEGINS TO BUILD EAST. MOST OF THE CWA SHOULD STAY ABOVE FREEZING...THOUGH PATCHY FROST WILL CERTAINLY BE POSSIBLE IN THE NORTH AND NORTHEAST WHERE OVERNIGHT LOWS IN THE 33-35F RANGE ARE EXPECTED. SATURDAY-WEDNESDAY... GUIDANCE IN DECENT AGREEMENT ON RIDGE BUILDING ACROSS WESTERN US WITH MAIN UPPER LEVEL JET STREAM SHIFTING WELL NORTH AND EAST OF CWA. ECMWF IS SHOWING A WEAK SHORTWAVE TROUGH ROTATING AROUND CLOSE UPPER LOW OVER GREAT LAKES POSSIBLY BRINGING SHOWERS/THUNDERSTORMS BACK TO NORTHERN PLAINS...POSSIBLY AS FAR WEST AS OUR CWA. THERE ISNT A LOT OF CONSISTENCY ON THIS WEAK FEATURE BETWEEN DETERMINISTIC AND ENSEMBLES SO I KEPT SUN/SUN NIGHT DRY. TEMPERATURES WILL MODERATE THROUGH THESE PERIODS WITH HIGH TEMPS IN THE UPPER 70S LOWER 80S BY EARLY NEXT WEEK AND PERSISTENT DRY CONDITIONS. CONSENSUS/MODEL BLEND SEEMED APPROPRIATE...SO LITTLE CHANGE FROM PREVIOUS FORECAST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 531 PM MDT WED OCT 1 2014 VFR CONDITIONS WILL CONTINUE AT KGLD AND KMCK FOR THE NEXT FEW HOURS. HOWEVER, A LINE OF STORMS WILL MOVE INTO BOTH SITES THIS EVENING WITH CIGS COMING DOWN TO THE MVFR LEVEL BY MID EVENING AND CONTINUING THROUGH EARLY MORNING. CONDITIONS SHOULD IMPROVE TO VFR BY MID DAY AND CONTINUE THROUGH THE AFTERNOON. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JRM LONG TERM...DR AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
136 PM MDT TUE SEP 30 2014 .SHORT TERM...(TONIGHT THROUGH WEDNESDAY) ISSUED AT 125 PM MDT TUE SEP 30 2014 LATEST WV IMAGERY AND RAP H5 ANALYSIS SHOW NEGATIVELY TILTED TROUGH OVER THE NORTHER PLAINS WITH CLOSED CENTER OVER SOUTH DAKOTA. SEVERAL WEAK EMBEDDED SHORTWAVE TROUGHS ARE CURRENTLY MOVING INTO CENTRAL COLORADO AND COULD BE IN LINE TO IMPACT OUR CWA OVERNIGHT. AT THE SURFACE A COLD FRONT CURRENTLY EXTEND FROM JUST EAST OF KMCK SOUTH ACROSS THE OK/TX PANHANDLES WITH SURFACE HIGH PRESSURE BEGINNING TO DEVELOP ALON THE CO/KS STATE LINE. WITH FRONT STILL OVER PAR OF THE CWA I CANT COMPLETELY RULE OUT AN ISOLATED SHOWER OR THUNDERSTORM OVER FAR EASTERN PART OF OUR CWA WHERE ML CAPE 500-1500 J/KG IS LINGERING. SUBSIDENCE HAS SUPPRESSED ANY CONVECTIVE REDEVELOPMENT SO FAR...AND GUIDANCE SHOWS ANY THREAT REMAINING EAST AS FRONT CONTINUES TO PUSH SOUTH AND EAST OVERNIGHT. AS WEAK SHORTWAVE TROUGH INDICATED BY NAM TO PASS OVER CWA TONIGHT COULD BRING A FEW LIGHT SHOWERS/SPRINKLES TO THE NORTHWEST PART OF THE CWA...HOWEVER THIS SHOULDNT AMOUNT TO MUCH CONSIDERING LIMITED MOISTURE/INSTABILITY. OTHER GUIDANCE IS FAVORING DRY CONDITIONS...SO DECIDED TO JUST KEEP MINIMAL SLIGHT CHANCE POPS IN PLACE 06-12Z PERIOD. NAM/RAP/SREF HINTING AT STRATUS/FOG DEVELOPMENT OVER EASTERN CWA WITH MOISTURE POOLING NEAR FRONTAL ZONE. NOT A LOT OF CONFIDENCE IN THIS AS MID-HIGH CLOUDS WILL BE INCREASING AND COULD LIMIT FOG/STRATUS POTENTIAL. LATEST GUIDANCE SHIFTING FRONT FURTHER EAST ON WEDNESDAY...LIMITING SEVERE POTENTIAL AND BETTER PRECIP POTENTIAL THROUGH MOST OF WEDNESDAY AFTERNOON PERIOD. CURRENTLY THINK THE BEST CHANCE FOR ANY AFTERNOON THUNDERSTORM DEVELOPMENT WILL BE TO BE AS FORCING INCREASES FROM THE WEST/NORTHWEST LATER WEDNESDAY AFTERNOON. I LIMITED 30-40 POPS TO THE LATE AFTERNOON IN OUR NORTHWEST. I KEPT SLIGHT CHANCE POPS OVER MOST OF THE CWA WEDNESDAY AFTERNOON MAINLY DUE TO BUILDING INSTABILITY AND AT LEAST WEAK FORCING BEHIND FRONTAL ZONE...THOUGH I WOULDNT BE SURPRISED IF WE REMAIN DRY UNTIL MAIN PUSH COMES IN LATER WEDNESDAY EVENING. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 125 PM MDT TUE SEP 30 2014 SHORTWAVE TROUGH WILL SWING THROUGH WEDNESDAY NIGHT WITH HIGH CHANCES OF PRECIPITATION. MODELS HAVE SHIFTED THE LOCATION OF THE SURFACE COLD FRONT FURTHER SOUTH...AS A RESULT THE THREAT FOR SEVERE WEATHER WILL LIKELY STAY SOUTH AS WELL. AVAILABLE INSTABILITY IN OUR AREA WILL ALMOST ALL BE ELEVATED WITH ONLY A SMALL AREA OF WEAK SBCAPE IN THE NORTHWEST EARLY IN THE EVENING. THE MAIN THREAT FOR ANY STRONGER STORMS THAT DEVELOP WILL BE MARGINALLY SEVERE HAIL DURING THE EVENING HOURS. RAIN WILL CONTINUE THROUGH THE OVERNIGHT WITH ONLY ISOLATED STORMS AS ELEVATED INSTABILITY DIMINISHES...POSSIBLY LINGERING IN EASTERN AREAS INTO THURSDAY MORNING BEFORE ENDING BY MID DAY THURSDAY. THE REMAINDER OF THE LONG TERM PERIOD WILL BE DOMINATED BY NORTHWEST FLOW ALOFT AND A LARGE RIDGE WHICH WILL SLOWLY BUILD OVER THE SOUTHWEST CONUS. THIS WILL RESULT IN DRY CONDITIONS AND TEMPERATURES GRADUALLY WARMING BACK TO NEAR NORMAL AFTER A BRIEF COOL DOWN THURSDAY AND FRIDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1129 AM MDT TUE SEP 30 2014 VFR CONDITIONS ARE EXPECTED TO PERSIST AT KGLD. LESS CONFIDENCE IN CIG/VIS FORECAST AT KMCK WITH SOME GUIDANCE INDICATING IFR OR LESS JUST WEST OF FRONTAL ZONE IN SOUTHCENTRAL NEBRASKA. GUIDANCE IS NOT VERY CONSISTENT ON THIS FRONT POSITION AND INCREASING MID LEVEL CLOUD COVER COULD HELP LIMIT ANY LOWER CIGS OR FOG DEVELOPMENT. WILL KEEP VFR AT BOTH TAF SITES AT THIS UPDATE. THERE COULD ALSO BE A FEW LIGHT SHOWERS OR VIRGA 06-12Z PERIOD AT KMCK THOUGH COVERAGE IS A QUESTION SO LEFT OUT. OTHER THAN BRIEF GUSTY WINDS OUT OF THE SW THIS AFTERNOON AT KMCK WINDS SHOULD GENERALLY REMAIN 10KT OR LESS AT BOTH TERMINALS. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...DJR LONG TERM...024 AVIATION...DR
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1202 PM CDT TUE SEP 30 2014 ...UPDATE TO AVIATION... .SYNOPSIS... ISSUED AT 932 AM CDT TUE SEP 30 2014 WV IMAGERY AND 12Z UPPER AIR ANALYSIS INDICATE A STRONG UPPER LEVEL SHORTWAVE TROUGH LIFTING NORTHWARD ACROSS THE NORTHERN PLAINS. MEANWHILE, A SECONDARY SHORTWAVE IS DIGGING SOUTHEAST ACROSS THE PACIFIC NORTHWEST. A SMALL, BUT STRONG +90KT UPPER LEVEL JET CORE IS LIFTING NORTHEAST ACROSS SOUTHEASTERN NEW MEXICO INTO THE TEXAS PANHANDLE. NEAR THE SURFACE, A LEE SIDE TROUGH OF LOW PRESSURE IS ANCHORED NEAR AND ALONG THE KANSAS/COLORADO BORDER. A MODEST AMOUNT OF MOISTURE REMAINS ACROSS CENTRAL AND SOUTHWEST KANSAS WITH SURFACE DEWPOINTS MAINLY IN THE 50S(F) WITH NEAR 60F IN SOUTH CENTRAL KANSAS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 123 AM CDT TUE SEP 30 2014 MODELS WERE IN GOOD AGREEMENT THIS MORNING WITH A NEGATIVELY TILTED UPPER LEVEL TROUGH LIFTING FROM EASTERN COLORADO AT 00Z TUESDAY INTO NEBRASKA BY 12Z TUESDAY. ANY LINGERING CONVECTION IN THE KINSLEY, STAFFORD, PRATT OR EVEN MEDICINE LODGE AREA IS EXPECTED TO END BETWEEN 15Z AND 18Z BASED ON LATEST HRRR AND RAP. WILL CONTINUE TO MONITOR THE ONGOING EARLY MORNING CONVECTION AND ADJUST TIMING AS NEEDED. TEMPERATURES TODAY WILL BE SLIGHTLY COOLER THAN YESTERDAY ACROSS NORTH CENTRAL AND PORTIONS OF FAR WESTERN KANSAS GIVEN THE 850MB TEMPERATURE TRENDS FROM 00Z TUESDAY TO 00Z WEDNESDAY. FURTHER EAST/SOUTHEAST NAM MODEL SOUNDINGS CONTINUE TO SUPPORT AFTERNOON HIGHS IN THE LOW TO MID 80S. ANOTHER UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE FROM EASTERN OREGON INTO THE CENTRAL ROCKIES BY LATE DAY WHICH STILL LOOKS REASONABLE GIVEN THE LATEST WATER VAPOR LOOP. AS THIS NEXT UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS TONIGHT THERE WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS ALONG AND EAST OF A SURFACE TROUGH AXIS WHICH WILL EXTEND FROM ROUGHLY HAYS TO MEADE. EAST OF THIS AXIS LATE TODAY THE SURFACE DEW POINTS WILL BE IN THE UPPER 50S TO LOWER 60S, CAPE VALUES WILL RANGE FROM 1000 TO 1500 J/KG, AND 0-6KM SHEAR IS FORECAST TO BE 30 TO 35 KNOTS AT 21Z TUESDAY AND 00Z WEDNESDAY. GIVEN THIS IF STORMS DO DEVELOP LATE TODAY A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. MAIN HAZARD AT THIS TIME WILL BE WIND GUSTS UP TO 60 MPH AND HAIL UP TO THE SIZE OF QUARTERS. GIVEN THE TIMING OF THE NEXT UPPER LEVEL TROUGH PRECIPITATION SHOULD MOVE EAST OF THE AREA BETWEEN MIDNIGHT AND 3 AM. A COLD FRONT DROP SOUTH INTO WESTERN KANSAS AFTER MIDNIGHT WHICH WILL RESULT IN LOWS FALLING BACK INTO THE 50 TO 55 DEGREE RANGE BEHIND THIS FRONT. SOUTH/SOUTHEAST OF THIS BOUNDARY PATCH FOG WILL BE POSSIBLE GIVEN LIGHT SOUTHEAST WINDS AND TEMPERATURES BOTTOMING OUT IN THE MID 50S TO LOWER 60S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 245 AM CDT TUE SEP 30 2014 AN UPPER LEVEL LONG WAVE TROUGH WILL BE CENTERED ABOVE THE ROCKIES WEDNESDAY INTO THURSDAY WITH AN UPPER LEVEL SHORTWAVE MOVING FROM THE INTER-MOUNTAIN WEST WEDNESDAY, THROUGH THE CENTRAL AND NORTHERN ROCKIES WEDNESDAY NIGHT, THEN THROUGH THE NORTHERN AND CENTRAL PLAINS ON THURSDAY. AN AREA OF LOW PRESSURE AT THE SURFACE WILL INTENSIFY ACROSS THE FORECAST AREA AS THIS SYSTEM APPROACHES WEDNESDAY WITH INCREASING CLOUDINESS IN THE AFTERNOON. A CHANCE OF THUNDERSTORMS WILL BE POSSIBLE FIRST ACROSS WEST CENTRAL KANSAS IN THE AFTERNOON AS MOISTURE WRAPS AROUND THE AFOREMENTIONED LOW. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS IN THE LATE AFTERNOON INTO THE EVENING WHERE SOUTHERLY FLOW AND INCREASED MOISTURE WILL BE OBSERVED. A FEW OF THESE STORMS MAY BECOME STRONG TO SEVERE IN THIS AREA WITH HAIL AND STRONG WINDS BEING THE MAIN CONCERN. THUNDERSTORM CHANCES SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY NIGHT WITH THE BEST CHANCE LOCATED ACROSS NORTHERN AND WEST CENTRAL KANSAS. A STRONG COLD FRONT IS THEN EXPECTED TO MOVE THROUGH THE CWA AFTER MIDNIGHT SHIFTING WINDS TO MORE OF A NORTHERLY DIRECTION. PRECIPITATION CHANCES END FROM WEST TO EAST THURSDAY MORNING WITH DECREASING CLOUDINESS THROUGHOUT THE DAY. MOSTLY CLEAR SKIES ARE FORECASTED THURSDAY NIGHT WITH WINDS SHIFTING TO THE NORTHWEST. AS FOR TEMPERATURES, HIGHS WEDNESDAY ARE EXPECTED TO RANGE FORM THE MID 70S ACROSS WEST CENTRAL KANSAS TO MID 80S ACROSS SOUTH CENTRAL KANSAS. LOWS WEDNESDAY NIGHT ARE ANTICIPATED TO RANGE FROM THE UPPER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 60 DEGREES ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES WILL BE FELT THURSDAY WITH HIGHS RANGING FROM THE UPPER 60S ACROSS THE I-70 CORRIDOR TO LOWER 70S ACROSS THE KS/OK BORDER. LOWS THURSDAY NIGHT ARE FORECASTED TO RANGE FROM THE LOWER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 50 DEGREES ACROSS SOUTH CENTRAL KANSAS. A DRIER WEATHER PATTERN IS IN STORE FOR THE REMAINDER OF THE FORECAST PERIOD AS THE UPPER LEVEL LONG WAVE TROUGH MOVES INTO THE EASTERN UNITED STATES AND AN UPPER LEVEL RIDGE BUILDS ACROSS THE WESTERN UNITED STATES. THIS WILL PLACE WESTERN KANSAS UNDER NORTHWEST FLOW ALOFT SUPPRESSING ANY ACTIVITY FROM DEVELOPING. HIGHS WILL GENERALLY BE IN THE LOWER 70S FRIDAY INCREASING TO THE LOWER 80S SATURDAY THROUGH MONDAY. LOWS WILL START OUT IN THE MID TO UPPER 40S SATURDAY MORNING INCREASING INTO THE LOWER 50S SUNDAY THROUGH TUESDAY MORNING. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1200 PM CDT TUE SEP 30 2014 VFR CONDITIONS WILL PREVAIL AT ALL TAF SITES THROUGH EARLY WEDNESDAY MORNING. LIGHT SOUTHERLY WINDS EARLY THIS AFTERNOON WILL BECOME MORE LIGHT AND VARIABLE THIS EVENING AS A SURFACE TROUGH OF LOW PRESSURE NEAR THE COLORADO BORDER EDGES SLOWLY EASTWARD ACROSS WESTERN KANSAS. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 57 81 54 / 40 30 20 30 GCK 82 54 79 51 / 10 10 20 50 EHA 80 51 79 50 / 10 10 10 30 LBL 84 53 81 53 / 30 10 10 20 HYS 81 58 78 53 / 40 30 30 50 P28 85 62 86 60 / 40 30 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJOHNSON SHORT TERM...BURGERT LONG TERM...HOVORKA_42 AVIATION...JJOHNSON
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
933 AM CDT TUE SEP 30 2014 ...UPDATE TO SYNOPSIS... .SYNOPSIS... ISSUED AT 932 AM CDT TUE SEP 30 2014 WV IMAGERY AND 12Z UPPER AIR ANALYSIS INDICATE A STRONG UPPER LEVEL SHORTWAVE TROUGH LIFTING NORTHWARD ACROSS THE NORTHERN PLAINS. MEANWHILE, A SECONDARY SHORTWAVE IS DIGGING SOUTHEAST ACROSS THE PACIFIC NORTHWEST. A SMALL, BUT STRONG +90KT UPPER LEVEL JET CORE IS LIFTING NORTHEAST ACROSS SOUTHEASTERN NEW MEXICO INTO THE TEXAS PANHANDLE. NEAR THE SURFACE, A LEE SIDE TROUGH OF LOW PRESSURE IS ANCHORED NEAR AND ALONG THE KANSAS/COLORADO BORDER. A MODEST AMOUNT OF MOISTURE REMAINS ACROSS CENTRAL AND SOUTHWEST KANSAS WITH SURFACE DEWPOINTS MAINLY IN THE 50S(F) WITH NEAR 60F IN SOUTH CENTRAL KANSAS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 123 AM CDT TUE SEP 30 2014 MODELS WERE IN GOOD AGREEMENT THIS MORNING WITH A NEGATIVELY TILTED UPPER LEVEL TROUGH LIFTING FROM EASTERN COLORADO AT 00Z TUESDAY INTO NEBRASKA BY 12Z TUESDAY. ANY LINGERING CONVECTION IN THE KINSLEY, STAFFORD, PRATT OR EVEN MEDICINE LODGE AREA IS EXPECTED TO END BETWEEN 15Z AND 18Z BASED ON LATEST HRRR AND RAP. WILL CONTINUE TO MONITOR THE ONGOING EARLY MORNING CONVECTION AND ADJUST TIMING AS NEEDED. TEMPERATURES TODAY WILL BE SLIGHTLY COOLER THAN YESTERDAY ACROSS NORTH CENTRAL AND PORTIONS OF FAR WESTERN KANSAS GIVEN THE 850MB TEMPERATURE TRENDS FROM 00Z TUESDAY TO 00Z WEDNESDAY. FURTHER EAST/SOUTHEAST NAM MODEL SOUNDINGS CONTINUE TO SUPPORT AFTERNOON HIGHS IN THE LOW TO MID 80S. ANOTHER UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE FROM EASTERN OREGON INTO THE CENTRAL ROCKIES BY LATE DAY WHICH STILL LOOKS REASONABLE GIVEN THE LATEST WATER VAPOR LOOP. AS THIS NEXT UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS TONIGHT THERE WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS ALONG AND EAST OF A SURFACE TROUGH AXIS WHICH WILL EXTEND FROM ROUGHLY HAYS TO MEADE. EAST OF THIS AXIS LATE TODAY THE SURFACE DEW POINTS WILL BE IN THE UPPER 50S TO LOWER 60S, CAPE VALUES WILL RANGE FROM 1000 TO 1500 J/KG, AND 0-6KM SHEAR IS FORECAST TO BE 30 TO 35 KNOTS AT 21Z TUESDAY AND 00Z WEDNESDAY. GIVEN THIS IF STORMS DO DEVELOP LATE TODAY A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. MAIN HAZARD AT THIS TIME WILL BE WIND GUSTS UP TO 60 MPH AND HAIL UP TO THE SIZE OF QUARTERS. GIVEN THE TIMING OF THE NEXT UPPER LEVEL TROUGH PRECIPITATION SHOULD MOVE EAST OF THE AREA BETWEEN MIDNIGHT AND 3 AM. A COLD FRONT DROP SOUTH INTO WESTERN KANSAS AFTER MIDNIGHT WHICH WILL RESULT IN LOWS FALLING BACK INTO THE 50 TO 55 DEGREE RANGE BEHIND THIS FRONT. SOUTH/SOUTHEAST OF THIS BOUNDARY PATCH FOG WILL BE POSSIBLE GIVEN LIGHT SOUTHEAST WINDS AND TEMPERATURES BOTTOMING OUT IN THE MID 50S TO LOWER 60S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 245 AM CDT TUE SEP 30 2014 AN UPPER LEVEL LONG WAVE TROUGH WILL BE CENTERED ABOVE THE ROCKIES WEDNESDAY INTO THURSDAY WITH AN UPPER LEVEL SHORTWAVE MOVING FROM THE INTER-MOUNTAIN WEST WEDNESDAY, THROUGH THE CENTRAL AND NORTHERN ROCKIES WEDNESDAY NIGHT, THEN THROUGH THE NORTHERN AND CENTRAL PLAINS ON THURSDAY. AN AREA OF LOW PRESSURE AT THE SURFACE WILL INTENSIFY ACROSS THE FORECAST AREA AS THIS SYSTEM APPROACHES WEDNESDAY WITH INCREASING CLOUDINESS IN THE AFTERNOON. A CHANCE OF THUNDERSTORMS WILL BE POSSIBLE FIRST ACROSS WEST CENTRAL KANSAS IN THE AFTERNOON AS MOISTURE WRAPS AROUND THE AFOREMENTIONED LOW. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS IN THE LATE AFTERNOON INTO THE EVENING WHERE SOUTHERLY FLOW AND INCREASED MOISTURE WILL BE OBSERVED. A FEW OF THESE STORMS MAY BECOME STRONG TO SEVERE IN THIS AREA WITH HAIL AND STRONG WINDS BEING THE MAIN CONCERN. THUNDERSTORM CHANCES SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY NIGHT WITH THE BEST CHANCE LOCATED ACROSS NORTHERN AND WEST CENTRAL KANSAS. A STRONG COLD FRONT IS THEN EXPECTED TO MOVE THROUGH THE CWA AFTER MIDNIGHT SHIFTING WINDS TO MORE OF A NORTHERLY DIRECTION. PRECIPITATION CHANCES END FROM WEST TO EAST THURSDAY MORNING WITH DECREASING CLOUDINESS THROUGHOUT THE DAY. MOSTLY CLEAR SKIES ARE FORECASTED THURSDAY NIGHT WITH WINDS SHIFTING TO THE NORTHWEST. AS FOR TEMPERATURES, HIGHS WEDNESDAY ARE EXPECTED TO RANGE FORM THE MID 70S ACROSS WEST CENTRAL KANSAS TO MID 80S ACROSS SOUTH CENTRAL KANSAS. LOWS WEDNESDAY NIGHT ARE ANTICIPATED TO RANGE FROM THE UPPER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 60 DEGREES ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES WILL BE FELT THURSDAY WITH HIGHS RANGING FROM THE UPPER 60S ACROSS THE I-70 CORRIDOR TO LOWER 70S ACROSS THE KS/OK BORDER. LOWS THURSDAY NIGHT ARE FORECASTED TO RANGE FROM THE LOWER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 50 DEGREES ACROSS SOUTH CENTRAL KANSAS. A DRIER WEATHER PATTERN IS IN STORE FOR THE REMAINDER OF THE FORECAST PERIOD AS THE UPPER LEVEL LONG WAVE TROUGH MOVES INTO THE EASTERN UNITED STATES AND AN UPPER LEVEL RIDGE BUILDS ACROSS THE WESTERN UNITED STATES. THIS WILL PLACE WESTERN KANSAS UNDER NORTHWEST FLOW ALOFT SUPPRESSING ANY ACTIVITY FROM DEVELOPING. HIGHS WILL GENERALLY BE IN THE LOWER 70S FRIDAY INCREASING TO THE LOWER 80S SATURDAY THROUGH MONDAY. LOWS WILL START OUT IN THE MID TO UPPER 40S SATURDAY MORNING INCREASING INTO THE LOWER 50S SUNDAY THROUGH TUESDAY MORNING. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 638 AM CDT TUE SEP 30 2014 THUNDERSTORMS WILL BE POSSIBLE ACROSS THE HYS TERMINAL THROUGH 13Z. OTHERWISE EXPECT CLEARING SKIES THROUGHOUT THE DAY. WINDS WILL GENERALLY BE FROM THE SOUTH SOUTHWEST. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 57 81 54 / 40 30 20 30 GCK 82 54 79 51 / 10 10 20 50 EHA 80 51 79 50 / 10 10 10 30 LBL 84 53 81 53 / 30 10 10 20 HYS 81 58 78 53 / 40 30 30 50 P28 85 62 86 60 / 40 30 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...JJOHNSON SHORT TERM...BURGERT LONG TERM...HOVORKA_42 AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
640 AM CDT TUE SEP 30 2014 ...UPDATED AVIATION SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 123 AM CDT TUE SEP 30 2014 MODELS WERE IN GOOD AGREEMENT THIS MORNING WITH A NEGATIVELY TILTED UPPER LEVEL TROUGH LIFTING FROM EASTERN COLORADO AT 00Z TUESDAY INTO NEBRASKA BY 12Z TUESDAY. ANY LINGERING CONVECTION IN THE KINSLEY, STAFFORD, PRATT OR EVEN MEDICINE LODGE AREA IS EXPECTED TO END BETWEEN 15Z AND 18Z BASED ON LATEST HRRR AND RAP. WILL CONTINUE TO MONITOR THE ONGOING EARLY MORNING CONVECTION AND ADJUST TIMING AS NEEDED. TEMPERATURES TODAY WILL BE SLIGHTLY COOLER THAN YESTERDAY ACROSS NORTH CENTRAL AND PORTIONS OF FAR WESTERN KANSAS GIVEN THE 850MB TEMPERATURE TRENDS FROM 00Z TUESDAY TO 00Z WEDNESDAY. FURTHER EAST/SOUTHEAST NAM MODEL SOUNDINGS CONTINUE TO SUPPORT AFTERNOON HIGHS IN THE LOW TO MID 80S. ANOTHER UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE FROM EASTERN OREGON INTO THE CENTRAL ROCKIES BY LATE DAY WHICH STILL LOOKS REASONABLE GIVEN THE LATEST WATER VAPOR LOOP. AS THIS NEXT UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS TONIGHT THERE WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS ALONG AND EAST OF A SURFACE TROUGH AXIS WHICH WILL EXTEND FROM ROUGHLY HAYS TO MEADE. EAST OF THIS AXIS LATE TODAY THE SURFACE DEW POINTS WILL BE IN THE UPPER 50S TO LOWER 60S, CAPE VALUES WILL RANGE FROM 1000 TO 1500 J/KG, AND 0-6KM SHEAR IS FORECAST TO BE 30 TO 35 KNOTS AT 21Z TUESDAY AND 00Z WEDNESDAY. GIVEN THIS IF STORMS DO DEVELOP LATE TODAY A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. MAIN HAZARD AT THIS TIME WILL BE WIND GUSTS UP TO 60 MPH AND HAIL UP TO THE SIZE OF QUARTERS. GIVEN THE TIMING OF THE NEXT UPPER LEVEL TROUGH PRECIPITATION SHOULD MOVE EAST OF THE AREA BETWEEN MIDNIGHT AND 3 AM. A COLD FRONT DROP SOUTH INTO WESTERN KANSAS AFTER MIDNIGHT WHICH WILL RESULT IN LOWS FALLING BACK INTO THE 50 TO 55 DEGREE RANGE BEHIND THIS FRONT. SOUTH/SOUTHEAST OF THIS BOUNDARY PATCH FOG WILL BE POSSIBLE GIVEN LIGHT SOUTHEAST WINDS AND TEMPERATURES BOTTOMING OUT IN THE MID 50S TO LOWER 60S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 245 AM CDT TUE SEP 30 2014 AN UPPER LEVEL LONG WAVE TROUGH WILL BE CENTERED ABOVE THE ROCKIES WEDNESDAY INTO THURSDAY WITH AN UPPER LEVEL SHORTWAVE MOVING FROM THE INTER-MOUNTAIN WEST WEDNESDAY, THROUGH THE CENTRAL AND NORTHERN ROCKIES WEDNESDAY NIGHT, THEN THROUGH THE NORTHERN AND CENTRAL PLAINS ON THURSDAY. AN AREA OF LOW PRESSURE AT THE SURFACE WILL INTENSIFY ACROSS THE FORECAST AREA AS THIS SYSTEM APPROACHES WEDNESDAY WITH INCREASING CLOUDINESS IN THE AFTERNOON. A CHANCE OF THUNDERSTORMS WILL BE POSSIBLE FIRST ACROSS WEST CENTRAL KANSAS IN THE AFTERNOON AS MOISTURE WRAPS AROUND THE AFOREMENTIONED LOW. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS IN THE LATE AFTERNOON INTO THE EVENING WHERE SOUTHERLY FLOW AND INCREASED MOISTURE WILL BE OBSERVED. A FEW OF THESE STORMS MAY BECOME STRONG TO SEVERE IN THIS AREA WITH HAIL AND STRONG WINDS BEING THE MAIN CONCERN. THUNDERSTORM CHANCES SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY NIGHT WITH THE BEST CHANCE LOCATED ACROSS NORTHERN AND WEST CENTRAL KANSAS. A STRONG COLD FRONT IS THEN EXPECTED TO MOVE THROUGH THE CWA AFTER MIDNIGHT SHIFTING WINDS TO MORE OF A NORTHERLY DIRECTION. PRECIPITATION CHANCES END FROM WEST TO EAST THURSDAY MORNING WITH DECREASING CLOUDINESS THROUGHOUT THE DAY. MOSTLY CLEAR SKIES ARE FORECASTED THURSDAY NIGHT WITH WINDS SHIFTING TO THE NORTHWEST. AS FOR TEMPERATURES, HIGHS WEDNESDAY ARE EXPECTED TO RANGE FORM THE MID 70S ACROSS WEST CENTRAL KANSAS TO MID 80S ACROSS SOUTH CENTRAL KANSAS. LOWS WEDNESDAY NIGHT ARE ANTICIPATED TO RANGE FROM THE UPPER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 60 DEGREES ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES WILL BE FELT THURSDAY WITH HIGHS RANGING FROM THE UPPER 60S ACROSS THE I-70 CORRIDOR TO LOWER 70S ACROSS THE KS/OK BORDER. LOWS THURSDAY NIGHT ARE FORECASTED TO RANGE FROM THE LOWER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 50 DEGREES ACROSS SOUTH CENTRAL KANSAS. A DRIER WEATHER PATTERN IS IN STORE FOR THE REMAINDER OF THE FORECAST PERIOD AS THE UPPER LEVEL LONG WAVE TROUGH MOVES INTO THE EASTERN UNITED STATES AND AN UPPER LEVEL RIDGE BUILDS ACROSS THE WESTERN UNITED STATES. THIS WILL PLACE WESTERN KANSAS UNDER NORTHWEST FLOW ALOFT SUPPRESSING ANY ACTIVITY FROM DEVELOPING. HIGHS WILL GENERALLY BE IN THE LOWER 70S FRIDAY INCREASING TO THE LOWER 80S SATURDAY THROUGH MONDAY. LOWS WILL START OUT IN THE MID TO UPPER 40S SATURDAY MORNING INCREASING INTO THE LOWER 50S SUNDAY THROUGH TUESDAY MORNING. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 638 AM CDT TUE SEP 30 2014 THUNDERSTORMS WILL BE POSSIBLE ACROSS THE HYS TERMINAL THROUGH 13Z. OTHERWISE EXPECT CLEARING SKIES THROUGHOUT THE DAY. WINDS WILL GENERALLY BE FROM THE SOUTH SOUTHWEST. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 57 81 54 / 20 20 20 30 GCK 82 54 79 51 / 10 10 20 50 EHA 80 51 79 50 / 10 10 10 30 LBL 84 53 81 53 / 10 10 10 20 HYS 81 58 78 53 / 40 20 30 50 P28 85 62 86 60 / 40 40 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...HOVORKA_42 AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
246 AM CDT TUE SEP 30 2014 ...UPDATED LONG TERM SECTION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 123 AM CDT TUE SEP 30 2014 MODELS WERE IN GOOD AGREEMENT THIS MORNING WITH A NEGATIVELY TILTED UPPER LEVEL TROUGH LIFTING FROM EASTERN COLORADO AT 00Z TUESDAY INTO NEBRASKA BY 12Z TUESDAY. ANY LINGERING CONVECTION IN THE KINSLEY, STAFFORD, PRATT OR EVEN MEDICINE LODGE AREA IS EXPECTED TO END BETWEEN 15Z AND 18Z BASED ON LATEST HRRR AND RAP. WILL CONTINUE TO MONITOR THE ONGOING EARLY MORNING CONVECTION AND ADJUST TIMING AS NEEDED. TEMPERATURES TODAY WILL BE SLIGHTLY COOLER THAN YESTERDAY ACROSS NORTH CENTRAL AND PORTIONS OF FAR WESTERN KANSAS GIVEN THE 850MB TEMPERATURE TRENDS FROM 00Z TUESDAY TO 00Z WEDNESDAY. FURTHER EAST/SOUTHEAST NAM MODEL SOUNDINGS CONTINUE TO SUPPORT AFTERNOON HIGHS IN THE LOW TO MID 80S. ANOTHER UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE FROM NORTHERN UTAH INTO THE CENTRAL ROCKIES BY MID DAY WHICH STILL LOOKS REASONABLE GIVEN THE LATEST WATER VAPOR LOOP. AS THIS NEXT UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS EARLY TONIGHT THERE WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS LATE TODAY ALONG AND EAST OF A SURFACE TROUGH AXIS WHICH WILL EXTEND FROM ROUGHLY HAYS TO MEADE. EAST OF THIS AXIS LATE TODAY THE SURFACE DEW POINTS WILL BE IN THE UPPER 50S TO LOWER 60S, CAPE VALUES WILL RANGE FROM 1000 TO 1500 J/KG, AND 0-6KM SHEAR IS FORECAST TO BE 30 TO 35 KNOTS AT 21Z TUESDAY AND 00Z WEDNESDAY. GIVEN THIS IF STORMS DO DEVELOP LATE TODAY A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. MAIN HAZARD AT THIS TIME WILL BE WIND GUSTS UP TO 60 MPH AND HAIL UP TO THE SIZE OF QUARTERS. GIVEN THE TIMING OF THE NEXT UPPER LEVEL TROUGH PRECIPITATION SHOULD MOVE EAST OF THE AREA BETWEEN MIDNIGHT AND 3 AM. A COLD FRONT DROP SOUTH INTO WESTERN KANSAS AFTER MIDNIGHT WHICH WILL RESULT IN LOWS FALLING BACK INTO THE 50 TO 55 DEGREE RANGE BEHIND THIS FRONT. SOUTH/SOUTHEAST OF THIS BOUNDARY PATCH FOG WILL BE POSSIBLE GIVEN LIGHT SOUTHEAST WINDS AND TEMPERATURES BOTTOMING OUT IN THE MID 50S TO LOWER 60S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 245 AM CDT TUE SEP 30 2014 AN UPPER LEVEL LONG WAVE TROUGH WILL BE CENTERED ABOVE THE ROCKIES WEDNESDAY INTO THURSDAY WITH AN UPPER LEVEL SHORTWAVE MOVING FROM THE INTER-MOUNTAIN WEST WEDNESDAY, THROUGH THE CENTRAL AND NORTHERN ROCKIES WEDNESDAY NIGHT, THEN THROUGH THE NORTHERN AND CENTRAL PLAINS ON THURSDAY. AN AREA OF LOW PRESSURE AT THE SURFACE WILL INTENSIFY ACROSS THE FORECAST AREA AS THIS SYSTEM APPROACHES WEDNESDAY WITH INCREASING CLOUDINESS IN THE AFTERNOON. A CHANCE OF THUNDERSTORMS WILL BE POSSIBLE FIRST ACROSS WEST CENTRAL KANSAS IN THE AFTERNOON AS MOISTURE WRAPS AROUND THE AFOREMENTIONED LOW. ADDITIONAL THUNDERSTORMS WILL BE POSSIBLE ACROSS CENTRAL AND SOUTH CENTRAL KANSAS IN THE LATE AFTERNOON INTO THE EVENING WHERE SOUTHERLY FLOW AND INCREASED MOISTURE WILL BE OBSERVED. A FEW OF THESE STORMS MAY BECOME STRONG TO SEVERE IN THIS AREA WITH HAIL AND STRONG WINDS BEING THE MAIN CONCERN. THUNDERSTORM CHANCES SPREAD ACROSS THE REMAINDER OF THE FORECAST AREA WEDNESDAY NIGHT WITH THE BEST CHANCE LOCATED ACROSS NORTHERN AND WEST CENTRAL KANSAS. A STRONG COLD FRONT IS THEN EXPECTED TO MOVE THROUGH THE CWA AFTER MIDNIGHT SHIFTING WINDS TO MORE OF A NORTHERLY DIRECTION. PRECIPITATION CHANCES END FROM WEST TO EAST THURSDAY MORNING WITH DECREASING CLOUDINESS THROUGHOUT THE DAY. MOSTLY CLEAR SKIES ARE FORECASTED THURSDAY NIGHT WITH WINDS SHIFTING TO THE NORTHWEST. AS FOR TEMPERATURES, HIGHS WEDNESDAY ARE EXPECTED TO RANGE FORM THE MID 70S ACROSS WEST CENTRAL KANSAS TO MID 80S ACROSS SOUTH CENTRAL KANSAS. LOWS WEDNESDAY NIGHT ARE ANTICIPATED TO RANGE FROM THE UPPER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 60 DEGREES ACROSS SOUTH CENTRAL KANSAS. COOLER TEMPERATURES WILL BE FELT THURSDAY WITH HIGHS RANGING FROM THE UPPER 60S ACROSS THE I-70 CORRIDOR TO LOWER 70S ACROSS THE KS/OK BORDER. LOWS THURSDAY NIGHT ARE FORECASTED TO RANGE FROM THE LOWER 40S ACROSS WEST CENTRAL KANSAS TO AROUND 50 DEGREES ACROSS SOUTH CENTRAL KANSAS. A DRIER WEATHER PATTERN IS IN STORE FOR THE REMAINDER OF THE FORECAST PERIOD AS THE UPPER LEVEL LONG WAVE TROUGH MOVES INTO THE EASTERN UNITED STATES AND AN UPPER LEVEL RIDGE BUILDS ACROSS THE WESTERN UNITED STATES. THIS WILL PLACE WESTERN KANSAS UNDER NORTHWEST FLOW ALOFT SUPPRESSING ANY ACTIVITY FROM DEVELOPING. HIGHS WILL GENERALLY BE IN THE LOWER 70S FRIDAY INCREASING TO THE LOWER 80S SATURDAY THROUGH MONDAY. LOWS WILL START OUT IN THE MID TO UPPER 40S SATURDAY MORNING INCREASING INTO THE LOWER 50S SUNDAY THROUGH TUESDAY MORNING. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1210 AM CDT TUE SEP 30 2014 A BAND OF THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST ACROSS WESTERN KANSAS DURING THE EARLY MORNING HOURS. BASED ON BUFR SOUNDINGS, HRRR, AND SURFACE OBSERVATIONS THE CLOUD BASED MAY BRIEFLY DROP INTO THE MVFR CATEGORY AS THESE THUNDERSTORMS PASS EARLY THIS MORNING. WIND GUSTS UP TO 30 KNOTS WILL ALSO BE POSSIBLE BRIEFLY, MAINLY IN THE GCK AREA BETWEEN 06Z AND 08Z TUESDAY. BASED ON THE LATEST HRRR, NAM, AND RAP THUNDERSTORMS WILL BE MORE LIKELY IN THE GCK AREA BETWEEN 06Z AND 09Z, DDC BETWEEN 08Z AND 10Z, AND HYS FROM 09Z TO 12Z. THE PREVAILING WINDS OVERNIGHT AND OUTSIDE THESE THUNDERSTORMS WILL BE SOUTHERLY AT AROUND 10 KNOTS. VFR CONDITIONS ARE ALSO EXPECTED OUTSIDE THESE STORMS OVERNIGHT. VFR CONDITONS WILL CONTINUE THROUGH EARLY TUESDAY AS A SURFACE TROUGH MOVES EAST ACROSS WESTERN KANSAS EARLY IN THE DAY. AS THIS TROUGH AXIS PASSES THE SOUTHERLY WINDS AT 10 TO 15 KNOTS WILL SHIFT TO THE SOUTHWEST. THE STRONGER WINDS FROM LATE MORNING INTO THE EARLY AFTERNOON WILL BE IN THE HAYS AND DODGE CITY AREA. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 57 81 54 / 20 20 20 30 GCK 82 54 79 51 / 10 10 20 50 EHA 80 51 79 50 / 10 10 10 30 LBL 84 53 81 53 / 10 10 10 20 HYS 81 58 78 53 / 30 20 30 50 P28 85 62 86 60 / 20 40 20 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...HOVORKA_42 AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
125 AM CDT TUE SEP 30 2014 ...UPDATED SHORT TERM DISCUSSION... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 123 AM CDT TUE SEP 30 2014 MODELS WERE IN GOOD AGREEMENT THIS MORNING WITH A NEGATIVELY TILTED UPPER LEVEL TROUGH LIFTING FROM EASTERN COLORADO AT 00Z TUESDAY INTO NEBRASKA BY 12Z TUESDAY. ANY LINGERING CONVECTION IN THE KINSLEY, STAFFORD, PRATT OR EVEN MEDICINE LODGE AREA IS EXPECTED TO END BETWEEN 15Z AND 18Z BASED ON LATEST HRRR AND RAP. WILL CONTINUE TO MONITOR THE ONGOING EARLY MORNING CONVECTION AND ADJUST TIMING AS NEEDED. TEMPERATURES TODAY WILL BE SLIGHTLY COOLER THAN YESTERDAY ACROSS NORTH CENTRAL AND PORTIONS OF FAR WESTERN KANSAS GIVEN THE 850MB TEMPERATURE TRENDS FROM 00Z TUESDAY TO 00Z WEDNESDAY. FURTHER EAST/SOUTHEAST NAM MODEL SOUNDINGS CONTINUE TO SUPPORT AFTERNOON HIGHS IN THE LOW TO MID 80S. ANOTHER UPPER LEVEL DISTURBANCE IS FORECAST TO MOVE FROM NORTHERN UTAH INTO THE CENTRAL ROCKIES BY MID DAY WHICH STILL LOOKS REASONABLE GIVEN THE LATEST WATER VAPOR LOOP. AS THIS NEXT UPPER LEVEL DISTURBANCE CROSSES WESTERN KANSAS EARLY TONIGHT THERE WILL BE A CHANCE FOR SCATTERED THUNDERSTORMS LATE TODAY ALONG AND EAST OF A SURFACE TROUGH AXIS WHICH WILL EXTEND FROM ROUGHLY HAYS TO MEADE. EAST OF THIS AXIS LATE TODAY THE SURFACE DEW POINTS WILL BE IN THE UPPER 50S TO LOWER 60S, CAPE VALUES WILL RANGE FROM 1000 TO 1500 J/KG, AND 0-6KM SHEAR IS FORECAST TO BE 30 TO 35 KNOTS AT 21Z TUESDAY AND 00Z WEDNESDAY. GIVEN THIS IF STORMS DO DEVELOP LATE TODAY A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE. MAIN HAZARD AT THIS TIME WILL BE WIND GUSTS UP TO 60 MPH AND HAIL UP TO THE SIZE OF QUARTERS. GIVEN THE TIMING OF THE NEXT UPPER LEVEL TROUGH PRECIPITATION SHOULD MOVE EAST OF THE AREA BETWEEN MIDNIGHT AND 3 AM. A COLD FRONT DROP SOUTH INTO WESTERN KANSAS AFTER MIDNIGHT WHICH WILL RESULT IN LOWS FALLING BACK INTO THE 50 TO 55 DEGREE RANGE BEHIND THIS FRONT. SOUTH/SOUTHEAST OF THIS BOUNDARY PATCH FOG WILL BE POSSIBLE GIVEN LIGHT SOUTHEAST WINDS AND TEMPERATURES BOTTOMING OUT IN THE MID 50S TO LOWER 60S. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 355 PM CDT MON SEP 29 2014 .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 143 PM CDT MON SEP 29 2014 STARTING WITH TUESDAY NIGHT, THE FIRST TROUGH WILL BE GOING EAST THROUGH THE AREA, TAKING THE 30 TO 40 PERCENT CHANCES FOR THUNDERSTORMS WITH IT ACROSS OUR SOUTHEAST AND EASTERN COUNTIES, EXITING THERE BY WEDNESDAY MORNING. THEN A COLD FRONT WILL BE ENTERING FROM THE NORTH TO NORTHWEST BY WEDNESDAY NIGHT, GIVING A SLIGHT CHANCE THUNDERSTORMS FIRST IN OUR EASTERN ZONES NEAR HAYS, SAINT JOHN AND MEDICINE LODGE, WHERE HIGHER DEWPOINTS WILL EXIST. AN UPPER LEVEL TROUGH WILL BE SLOWLY MIGRATING THROUGH TO THE EAST WEDNESDAY NIGHT AND THURSDAY. AS THE FRONT ADVANCES SOUTHEAST THROUGH OUR FORECAST AREA WEDNESDAY NIGHT, RAINSHOWER CHANCES WILL INCREASE IN THE NORTH AND NORTHWEST INTO THE 50 PERCENT CHANCE RANGE, AND INTO THE 20 TO 30 PERCENT CHANCE RANGE ACROSS OUR SOUTHERN ZONES SUCH AS MORTON, MEADE AND COLDWATER COUNTIES. NOT TOO MUCH RAINFALL IS ANTICIPATED WEDNESDAY INTO THURSDAY, AS CONVECTIVE ACTIVITY WILL BE LIMITED. THEN THE COLD FRONT WILL SETTLE SOUTHEASTWARD ON THURSDAY, BRINGING PERHAPS THE COLDEST AIR OF THE RECENT FALL PERIOD TO SOUTHWEST KANSAS. HIGHS ON THURSDAY WILL ONLY REACH THE MID 60S IN THE SCOTT CITY TO WAKEENEY AREAS, AND WILL BE AROUND 70F DEGREES ALONG THE OKLAHOMA BORDER. BEYOND THURSDAY, THE UPPER FLOW REMAINS NORTHWESTERLY THROUGH MONDAY. NO RAINFALL IS EXPECTED THROUGH MONDAY, EITHER. FRIDAY WILL HAVE COOL MODERATING TEMPS WITH HIGHS IN THE LOWER TO MID 70S, BUT THEN SHOULD INCREASE IN THE LOWER TO MID 80S RANGE SATURDAY INTO MONDAY. MINIMUM TEMPERATURES WILL AVERAGE IN THE LOWER TO MID 50S TUESDAY AND WEDNESDAY NIGHTS, AS WELL AS ON SATURDAY AND SUNDAY NIGHTS. IN BETWEEN, THURSDAY AND FRIDAY NIGHTS WILL BE COOL, WITH MINS IN THE 40S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1210 AM CDT TUE SEP 30 2014 A BAND OF THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST ACROSS WESTERN KANSAS DURING THE EARLY MORNING HOURS. BASED ON BUFR SOUNDINGS, HRRR, AND SURFACE OBSERVATIONS THE CLOUD BASED MAY BRIEFLY DROP INTO THE MVFR CATAGORY AS THESE THUNDERSTORMS PASS EARLY THIS MORNING. WIND GUSTS UP TO 30 KNOTS WILL ALSO BE POSSIBLE BRIEFLY, MAINLY IN THE GCK AREA BETWEEN 06Z AND 08Z TUESDAY. BASED ON THE LATEST HRRR, NAM, AND RAP THUNDERSTORMS WILL BE MORE LIKELY IN THE GCK AREA BETWEEN 06Z AND 09Z, DDC BETWEEN 08Z AND 10Z, AND HYS FROM 09Z TO 12Z. THE PREVAILING WINDS OVERNIGHT AND OUTSIDE THESE THUNDERSTORMS WILL BE SOUTHERLY AT AROUND 10 KNOTS. VFR CONDITIONS ARE ALSO EXPECTED OUTSIDE THESE STORMS OVERNIGHT. VFR CONDITONS WILL CONTINUE THROUGH EARLY TUESDAY AS A SURFACE TROUGH MOVES EAST ACROSS WESTERN KANSAS EARLY IN THE DAY. AS THIS TROUGH AXIS PASSES THE SOUTHERLY WINDS AT 10 TO 15 KNOTS WILL SHIFT TO THE SOUTHWEST. THE STRONGER WINDS FROM LATE MORNING INTO THE EARLY AFTERNOON WILL BE IN THE HAYS AND DODGE CITY AREA. && .PRELIMINARY POINT TEMPS/POPS... DDC 84 57 81 52 / 20 20 20 30 GCK 82 54 78 49 / 10 10 30 40 EHA 80 51 78 49 / 10 10 10 30 LBL 84 53 80 51 / 10 10 10 30 HYS 81 58 77 52 / 40 20 40 50 P28 85 62 86 59 / 30 40 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...BURKE AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1213 AM CDT TUE SEP 30 2014 ...UPDATED SYNOPSIS AND AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 1210 AM CDT TUE SEP 30 2014 AT 00Z TUESDAY A 500MB TROUGH WAS LOCATED FROM WESTERN COLORADO INTO NORTHEAST NEW MEXICO. ANOTHER UPPER TROUGH APPEARS TO BE LOCATED UPSTREAM IN NORTHERN UTAH. A +80 KNOT 250MB JET STREAK EXTENDED FROM WESTERN NEW MEXICO INTO THE PANHANDLE OF TEXAS. OVER THE CENTRAL HIGH PLAINS A SURFACE TO 850MB TROUGH EXTENDED FROM ARE AREA OF LOW PRESSURE IN NORTHEASTERN COLORADO TO NORTHEAST NEW MEXICO. SURFACE DEW POINTS AHEAD OF THIS SURFACE BOUNDARY MAINLY IN THE MID TO UPPER 50S. EVENING CONVECTION WAS FOCUSED ALONG THIS BOUNDARY AND AHEAD OF THE COLORADO/NEW MEXICO UPPER LEVEL TROUGH. 850MB TEMPERATURES AT 00Z TUESDAY WERE +19C AT NORTH PLATTE, +20C AT DODGE CITY AND AMARILLO. 700MB TEMPERATURES RANGED FROM +6C AT NORTH PLATTE TO +9C AT AMARILLO. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 200 PM CDT MON SEP 29 2014 SHORT TERM MODELS INDICATE AN UPPER LEVEL SHORTWAVE TROUGH STRENGTHENING AS IT LIFTS NORTHEAST OUT OF THE DESERT SOUTHWEST INTO COLORADO TONIGHT SETTING THE STAGE FOR SCATTERED THUNDERSTORM DEVELOPMENT FROM NORTHEASTERN NEW MEXICO NORTH-NORTHEASTWARD INTO EASTERN COLORADO AND WESTERN NEBRASKA. AS A STRONG H5 VORT MAX LIFTS NORTHEAST ACROSS THE ROCKIES OF SOUTHERN COLORADO, A SURFACE LOW WILL CONTINUE TO DEEPEN ACROSS NORTHEASTERN COLORADO ENHANCING THE SOUTH TO SOUTHEASTERLY UPSLOPE FLOW ACROSS THE WESTERN HIGH PLAINS, AND SUBSEQUENTLY DRAWING MORE MOISTURE INTO THE REGION. MEANWHILE, THE STRONG JET CORE EXITING THE SHORTWAVE TROUGH AXIS, WILL CLIMB NORTHEAST ACROSS EXTREME EASTERN COLORADO THIS EVENING MAKING DYNAMIC SUPPORT ALOFT MUCH MORE FAVORABLE WITH WINDS IN EXCEEDING 80KT. DEEP LAYER SHEAR, STEEP LOW/MID LEVEL LAPSE RATES, AND INCREASING INSTABILITY IN CONJUNCTION WITH THE ARRIVAL OF THE STRENGTHENING UPPER LEVEL SHORTWAVE, WILL TRIGGER THUNDERSTORMS ACROSS EASTERN COLORADO LATE THIS AFTERNOON IN THE VICINITY OF THE SURFACE TROUGH. DEVELOPING STORMS WILL THEN MOVE EAST INTO PORTIONS OF EXTREME WESTERN KANSAS LATER THIS EVENING AND INTO THE OVERNIGHT HOURS. NAM/GFS MODEL SOUNDINGS SUGGEST THE POTENTIAL FOR VERY STRONG TO SEVERE STORMS DUE TO FAVORABLE VERTICAL SHEAR PROFILES DEVELOPING THROUGH THIS EVENING AS THE WINDS ALOFT STRENGTHEN, NOT TO MENTION MUCAPE VALUES CLIMBING NEAR 1000 J/KG OUT NEAR THE COLORADO BORDER. STORMS MAY CONTINUE TO MIGRATE EASTWARD OVERNIGHT BUT ARE EXPECTED TO LESSEN IN INTENSITY AS THEY MOVE INTO LESS UNSTABLE AIR. LOWS TUESDAY MORNING WILL BE SLIGHTLY WARMER THAN THE MID TO UPPER 50S(F) OBSERVED ACROSS CENTRAL AND SOUTHWEST KANSAS THIS MORNING AS A STRONG LOW LEVEL SOUTHERLY FLOW PERSISTS ACROSS WESTERN KANSAS OVERNIGHT, DRAWING WARMER AIR NORTHWARD INTO THE REGION. EXPECT LOWS DOWN INTO THE UPPER 50S(F) ACROSS WEST CENTRAL KANSAS TO THE LOWER AND MID 60S(F) ACROSS SOUTH CENTRAL KANSAS. MARGINAL WARM AIR ADVECTION WILL CONTINUE TUESDAY ALLOWING H85 TEMPERATURES TO REACH UP INTO THE LOWER 20S(C) ACROSS MUCH OF CENTRAL AND SOUTHWEST KANSAS. LOOK FOR HIGHS UP INTO THE MID TO UPPER 70S(F) IN WEST CENTRAL KANSAS TO THE LOWER TO MID 80S(F) IN SOUTH CENTRAL KANSAS TUESDAY AFTERNOON. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 355 PM CDT MON SEP 29 2014 .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 143 PM CDT MON SEP 29 2014 STARTING WITH TUESDAY NIGHT, THE FIRST TROUGH WILL BE GOING EAST THROUGH THE AREA, TAKING THE 30 TO 40 PERCENT CHANCES FOR THUNDERSTORMS WITH IT ACROSS OUR SOUTHEAST AND EASTERN COUNTIES, EXITING THERE BY WEDNESDAY MORNING. THEN A COLD FRONT WILL BE ENTERING FROM THE NORTH TO NORTHWEST BY WEDNESDAY NIGHT, GIVING A SLIGHT CHANCE THUNDERSTORMS FIRST IN OUR EASTERN ZONES NEAR HAYS, SAINT JOHN AND MEDICINE LODGE, WHERE HIGHER DEWPOINTS WILL EXIST. AN UPPER LEVEL TROUGH WILL BE SLOWLY MIGRATING THROUGH TO THE EAST WEDNESDAY NIGHT AND THURSDAY. AS THE FRONT ADVANCES SOUTHEAST THROUGH OUR FORECAST AREA WEDNESDAY NIGHT, RAINSHOWER CHANCES WILL INCREASE IN THE NORTH AND NORTHWEST INTO THE 50 PERCENT CHANCE RANGE, AND INTO THE 20 TO 30 PERCENT CHANCE RANGE ACROSS OUR SOUTHERN ZONES SUCH AS MORTON, MEADE AND COLDWATER COUNTIES. NOT TOO MUCH RAINFALL IS ANTICIPATED WEDNESDAY INTO THURSDAY, AS CONVECTIVE ACTIVITY WILL BE LIMITED. THEN THE COLD FRONT WILL SETTLE SOUTHEASTWARD ON THURSDAY, BRINGING PERHAPS THE COLDEST AIR OF THE RECENT FALL PERIOD TO SOUTHWEST KANSAS. HIGHS ON THURSDAY WILL ONLY REACH THE MID 60S IN THE SCOTT CITY TO WAKEENEY AREAS, AND WILL BE AROUND 70F DEGREES ALONG THE OKLAHOMA BORDER. BEYOND THURSDAY, THE UPPER FLOW REMAINS NORTHWESTERLY THROUGH MONDAY. NO RAINFALL IS EXPECTED THROUGH MONDAY, EITHER. FRIDAY WILL HAVE COOL MODERATING TEMPS WITH HIGHS IN THE LOWER TO MID 70S, BUT THEN SHOULD INCREASE IN THE LOWER TO MID 80S RANGE SATURDAY INTO MONDAY. MINIMUM TEMPERATURES WILL AVERAGE IN THE LOWER TO MID 50S TUESDAY AND WEDNESDAY NIGHTS, AS WELL AS ON SATURDAY AND SUNDAY NIGHTS. IN BETWEEN, THURSDAY AND FRIDAY NIGHTS WILL BE COOL, WITH MINS IN THE 40S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1210 AM CDT TUE SEP 30 2014 A BAND OF THUNDERSTORMS WILL WEAKEN AS THEY MOVE EAST ACROSS WESTERN KANSAS DURING THE EARLY MORNING HOURS. BASED ON BUFR SOUNDINGS, HRRR, AND SURFACE OBSERVATIONS THE CLOUD BASED MAY BRIEFLY DROP INTO THE MVFR CATAGORY AS THESE THUNDERSTORMS PASS EARLY THIS MORNING. WIND GUSTS UP TO 30 KNOTS WILL ALSO BE POSSIBLE BRIEFLY, MAINLY IN THE GCK AREA BETWEEN 06Z AND 08Z TUESDAY. BASED ON THE LATEST HRRR, NAM, AND RAP THUNDERSTORMS WILL BE MORE LIKELY IN THE GCK AREA BETWEEN 06Z AND 09Z, DDC BETWEEN 08Z AND 10Z, AND HYS FROM 09Z TO 12Z. THE PREVAILING WINDS OVERNIGHT AND OUTSIDE THESE THUNDERSTORMS WILL BE SOUTHERLY AT AROUND 10 KNOTS. VFR CONDITIONS ARE ALSO EXPECTED OUTSIDE THESE STORMS OVERNIGHT. VFR CONDITONS WILL CONTINUE THROUGH EARLY TUESDAY AS A SURFACE TROUGH MOVES EAST ACROSS WESTERN KANSAS EARLY IN THE DAY. AS THIS TROUGH AXIS PASSES THE SOUTHERLY WINDS AT 10 TO 15 KNOTS WILL SHIFT TO THE SOUTHWEST. THE STRONGER WINDS FROM LATE MORNING INTO THE EARLY AFTERNOON WILL BE IN THE HAYS AND DODGE CITY AREA. && .PRELIMINARY POINT TEMPS/POPS... DDC 57 81 52 71 / 20 20 30 20 GCK 54 78 49 70 / 10 30 40 20 EHA 51 78 49 70 / 10 10 30 20 LBL 53 80 51 71 / 10 10 30 20 HYS 58 77 52 68 / 20 40 50 30 P28 62 86 59 74 / 40 30 30 30 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BURGERT SHORT TERM...JJOHNSON LONG TERM...BURKE AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS PADUCAH KY
1148 AM CDT Tue Sep 30 2014 .UPDATE... Issued at 1148 AM CDT Tue Sep 30 2014 Updated aviation section only. && .SHORT TERM...(Today through Thursday night) Issued at 247 AM CDT TUE SEP 30 2014 The main weather system for the short term forecast period still remains focused on Thursday and Thursday night. Medium range, and now, short range guidance suggests that the best lift and forcing shall remain limited to the aforementioned time period. This has been consistent with the model runs since late last week. With respect to severe potential, using the operational GFS as a convective template, the time period between 23z-04z (6 pm - 11 pm CDT) Friday, inclusive, is supportive of at least isolated to scattered severe storms. The 0-1km and 0-6km Bulk shear remains between 20-25 knots and 40 to 45 knots, respectively between 00z and 06z Friday...with Mixed Layer and Most Unstable layer CAPE edging into a northeast oriented gradient between 1200-1400 j/kg. The Day 3 Slight Risk area defined by SPC fits very well with the area of interest over Southeast Missouri Thursday evening. At this point in time, suspect that there may be some wind damage potential (entraining very dry air aloft into marginally favorable layer lapse rates) with a squall line moving into and off of the Southeast Missouri foothills between 00-03z Friday. Beyond that time, low level convergence, originally associated with a surface wave moving through eastern Missouri at the time, will take most of the enhanced low level convergence and shear rapidly northeast out of the area by 06z Friday. Other than this limited severe weather potential, a broad swatch of 1-1.25 inches of rain will be the primary activity with the passage of the weather system Thursday and Thursday night. In the very near term, fog potential will still be an issue for this morning. Issued an SPS for locally dense fog once again. All though the high resolution 3km HRRR continues to overreach on coverage, the 13km RAP and 4km NAM-WRF (NMM version) appear to suggest that Southeast Illinois could see more widespread fog through daybreak. The influx of moisture should increase after today will limit the 25-30 degree diurnal swing of temperatures experience during the last few days. Went slightly above the warmest guidance today for maximum temperatures. More normal diurnal range of temperatures can then be expected prior to the development of convection late night Wednesday. .LONG TERM...(Friday through Monday) Issued at 247 AM CDT TUE SEP 30 2014 The pattern will generally be an upper level trof over the east U.S. with strong flow coming into the CONUS across the Pacific NW, and some riding over the SW U.S. extending into Mexico. Mainly dry weather is expected. A cold front will depart the area early Friday with decreasing chances of showers in the morning. High pressure will build in, and lead to a cooler Saturday. Not sure how cool though, as the GFS shows 925-850mb warm advection developing as early as 12-18z Sat. Temperatures will moderate back to seasonal norms Sunday-Monday. Will keep an eye on a frontal system the models advertise Sunday night into early Monday. 00z GFS develops some convection, however prior runs did not. ECMWF stays generally dry. Will keep it dry for now and monitor trends. && .AVIATION... Issued at 1148 AM CDT Tue SEP 30 2014 Under ridging aloft, and with a slack sfc pressure pattern, winds will be very light and variable for the rest of today and into much of the night under virtually clear skies. However, the overall trend for the sfc winds should be to take on an erly component as time goes on. Greater winds just off the sfc are expected to stir the boundary layer enough to preclude the formation of significant fog late in the night. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...Smith LONG TERM...CN Aviation...DB
AREA FORECAST DISCUSSION
NWS PADUCAH KY
607 AM CDT Tue Sep 30 2014 .SHORT TERM...(Today through Thursday night) Issued at 247 AM CDT TUE SEP 30 2014 The main weather system for the short term forecast period still remains focused on Thursday and Thursday night. Medium range, and now, short range guidance suggests that the best lift and forcing shall remain limited to the aforementioned time period. This has been consistent with the model runs since late last week. With respect to severe potential, using the operational GFS as a convective template, the time period between 23z-04z (6 pm - 11 pm CDT) Friday, inclusive, is supportive of at least isolated to scattered severe storms. The 0-1km and 0-6km Bulk shear remains between 20-25 knots and 40 to 45 knots, respectively between 00z and 06z Friday...with Mixed Layer and Most Unstable layer CAPE edging into a northeast oriented gradient between 1200-1400 j/kg. The Day 3 Slight Risk area defined by SPC fits very well with the area of interest over Southeast Missouri Thursday evening. At this point in time, suspect that there may be some wind damage potential (entraining very dry air aloft into marginally favorable layer lapse rates) with a squall line moving into and off of the Southeast Missouri foothills between 00-03z Friday. Beyond that time, low level convergence, originally associated with a surface wave moving through eastern Missouri at the time, will take most of the enhanced low level convergence and shear rapidly northeast out of the area by 06z Friday. Other than this limited severe weather potential, a broad swatch of 1-1.25 inches of rain will be the primary activity with the passage of the weather system Thursday and Thursday night. In the very near term, fog potential will still be an issue for this morning. Issued an SPS for locally dense fog once again. All though the high resolution 3km HRRR continues to overreach on coverage, the 13km RAP and 4km NAM-WRF (NMM version) appear to suggest that Southeast Illinois could see more widespread fog through daybreak. The influx of moisture should increase after today will limit the 25-30 degree diurnal swing of temperatures experience during the last few days. Went slightly above the warmest guidance today for maximum temperatures. More normal diurnal range of temperatures can then be expected prior to the development of convection late night Wednesday. .LONG TERM...(Friday through Monday) Issued at 247 AM CDT TUE SEP 30 2014 The pattern will generally be an upper level trof over the east U.S. with strong flow coming into the CONUS across the Pacific NW, and some riding over the SW U.S. extending into Mexico. Mainly dry weather is expected. A cold front will depart the area early Friday with decreasing chances of showers in the morning. High pressure will build in, and lead to a cooler Saturday. Not sure how cool though, as the GFS shows 925-850mb warm advection developing as early as 12-18z Sat. Temperatures will moderate back to seasonal norms Sunday-Monday. Will keep an eye on a frontal system the models advertise Sunday night into early Monday. 00z GFS develops some convection, however prior runs did not. ECMWF stays generally dry. Will keep it dry for now and monitor trends. && .AVIATION... Issued at 607 AM CDT Tue SEP 3029 2014 Little change from previous forecast package. Kept lingering mention of IFR/MVFR fog for the first hour at KCGI/KPAH, but shifted immediately to VFR conditions for the remainder of the forecast period. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...Smith LONG TERM...CN Aviation...Smith
AREA FORECAST DISCUSSION
NWS PADUCAH KY
248 AM CDT Tue Sep 30 2014 .SHORT TERM...(Today through Thursday night) Issued at 247 AM CDT TUE SEP 30 2014 The main weather system for the short term forecast period still remains focused on Thursday and Thursday night. Medium range, and now, short range guidance suggests that the best lift and forcing shall remain limited to the aforementioned time period. This has been consistent with the model runs since late last week. With respect to severe potential, using the operational GFS as a convective template, the time period between 23z-04z (6 pm - 11 pm CDT) Friday, inclusive, is supportive of at least isolated to scattered severe storms. The 0-1km and 0-6km Bulk shear remains between 20-25 knots and 40 to 45 knots, respectively between 00z and 06z Friday...with Mixed Layer and Most Unstable layer CAPE edging into a northeast oriented gradient between 1200-1400 j/kg. The Day 3 Slight Risk area defined by SPC fits very well with the area of interest over Southeast Missouri Thursday evening. At this point in time, suspect that there may be some wind damage potential (entraining very dry air aloft into marginally favorable layer lapse rates) with a squall line moving into and off of the Southeast Missouri foothills between 00-03z Friday. Beyond that time, low level convergence, originally associated with a surface wave moving through eastern Missouri at the time, will take most of the enhanced low level convergence and shear rapidly northeast out of the area by 06z Friday. Other than this limited severe weather potential, a broad swatch of 1-1.25 inches of rain will be the primary activity with the passage of the weather system Thursday and Thursday night. In the very near term, fog potential will still be an issue for this morning. Issued an SPS for locally dense fog once again. All though the high resolution 3km HRRR continues to overreach on coverage, the 13km RAP and 4km NAM-WRF (NMM version) appear to suggest that Southeast Illinois could see more widespread fog through daybreak. The influx of moisture should increase after today will limit the 25-30 degree diurnal swing of temperatures experience during the last few days. Went slightly above the warmest guidance today for maximum temperatures. More normal diurnal range of temperatures can then be expected prior to the development of convection late night Wednesday. .LONG TERM...(Friday through Monday) Issued at 247 AM CDT TUE SEP 30 2014 The pattern will generally be an upper level trof over the east U.S. with strong flow coming into the CONUS across the Pacific NW, and some riding over the SW U.S. extending into Mexico. Mainly dry weather is expected. A cold front will depart the area early Friday with decreasing chances of showers in the morning. High pressure will build in, and lead to a cooler Saturday. Not sure how cool though, as the GFS shows 925-850mb warm advection developing as early as 12-18z Sat. Temperatures will moderate back to seasonal norms Sunday-Monday. Will keep an eye on a frontal system the models advertise Sunday night into early Monday. 00z GFS develops some convection, however prior runs did not. ECMWF stays generally dry. Will keep it dry for now and monitor trends. && .AVIATION... Issued at 555 PM CDT MON SEP 29 2014 Patchy vsby restrictions in fog is possible tonight, like previous nights. Will monitor evening trends, however, as drier air did work down the column late this afternoon. Otherwise VFR continues with few-sct diurnal cu developing in 4-5K foot range again tmrw. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...NONE. MO...NONE. IN...NONE. KY...NONE. && $$ SHORT TERM...Smith LONG TERM...CN Aviation...DH
AREA FORECAST DISCUSSION
NWS GRAY ME
623 PM EDT TUE SEP 30 2014 .SYNOPSIS... SURFACE HIGH PRESSURE WILL HOLD OVER NORTHERN NEW ENGLAND THROUGH FRIDAY. HOWEVER...A MOIST NORTHEAST FLOW WILL KEEP CLOUDS AND A CHANCE OF SHOWERS AROUND THROUGH MIDWEEK. A COLD FRONT CROSSES THE REGION SATURDAY WITH LOW PRESSURE DEVELOPING ALONG IT. WEAK HIGH PRESSURE FOLLOWS IN THE WAKE OF THE LOW SUNDAY AND MONDAY. && .NEAR TERM /THROUGH WEDNESDAY/... UPDATE... MOST OF THE LASTEST MESOSCALE MODELS NOW SHOWING PRECIP ENTERING THE SOUTHWEST COAST OF MAINE AND THE SEACOAST OF NH AROUND 09Z...AND CONTINUING TO AROUND 18Z. THERE ARE A COUPLE OUTLIERS SUCH AS THE HRRR WHICH BRINGS THE SHOWER ACTIVITY ALL THE WAY INTO CENTRAL NH BY 04Z. FEEL THIS IS SOMEWHAT OVERAGRESSIVE WITH THE FAST MOVEMENT/TIMING OF THE PRECIP. HAVE ADJUSTED POPS BASED ON CURRENT RADAR TRENDS. HAVE ALSO ADJUSTED DEW POINT AND CLOUD COVER GRIDS FOR THE NEXT SEVERAL HOURS. PREV DISC... SOME DRIER AIR AND CLEARING NORTHERN NEW HAMPSHIRE AND WESTERN MAINE NEAR THE INTERNATIONAL BORDER...OTHERWISE CLOUDS WERE REMAINING IN PLACE ACROSS THE REMAINDER OF THE FORECAST AREA. CLOUDS SHOULD FILL BACK IN TONIGHT WITH LOW CLOUD AND FOG. THE UPPER LOW OVER THE EASTERN GREAT LAKES WILL SLIDE EAST WITH SHOWERS/LIGHT RAIN SPREADING INTO SOUTHERN NEW HAMPSHIRE AND EXTREME SOUTHWEST MAINE BY DAWN. LOWS SHOULD RANGE FROM MID 40S NORTH TO THE LOWER 50S SOUTH TONIGHT. && .SHORT TERM /WEDNESDAY NIGHT/... SHOWERS/LIGHT RAIN OVER THE SOUTHERN NEW HAMPSHIRE AND SOUTHWEST MAINE SHOULD DIMINISH IN COVERAGE BY AFTERNOON AS THE UPPER LOW PIVOTS SOUTHEAST AND SOME DRIER AIR WORKS IN FROM THE NORTH WITH THE SURFACE HIGH. THERE WILL BE A TIGHT NORTH TO SOUTH GRADIENT IN THE PRECIPITATION SHIELD TOMORROW WITH AREAS NEAR THE INTERNATIONAL BORDER LIKELY STAYING DRY. HIGHS SHOULD BE A FEW DEGREES EITHER SIDE OF 60 WITH WARMEST READINGS LIKELY UPPER CONNECTICUT VALLEY AND ALONG THE INTERNATIONAL BORDER GIVEN NO PRECIPITATION AND THINNING CLOUD COVER. ANY LINGERING SHOWERS END WEDNESDAY NIGHT AS THE UPPER LOW SLIDES OFFSHORE. WE`LL SEE BROKEN CLOUDS WITH AREAS OF FOG DEVELOPING. LOWS SHOULD RANGE FROM THE MID 40S TO LOWER 50S. && .LONG TERM /THURSDAY THROUGH TUESDAY/... COASTAL LOW PRESSURE WILL ATTEMPT TO MOVE FARTHER OFFSHORE THURSDAY FOLLOWED CLOSELY BY THE PARENT UPPER LEVEL LOW...HOWEVER IT STALLS DUE TO BLOCKING FARTHER DOWNSTREAM. RESIDUAL WRAP AROUND MOISTURE FROM THIS STALLED SYSTEM WILL KEEP THINGS MOIST ALONG THE COAST BUT EXPECT FOG AND PERHAPS DRIZZLE AT THE MOST IN THE EARLY MORNING HOURS. OTHERWISE ANY LIGHT RAIN SHOULD REMAIN OFFSHORE. A FEW SHOWERS ATTEMPT TO BACK ONSHORE ONCE AGAIN FRIDAY AND MAY REACH AS FAR AS THE MIDCOAST FRIDAY NIGHT. A SPOKE OF ENERGY/WEAK SURFACE TROUGH SHIFTS BACK WEST FROM THE COASTAL STORM AND PROVIDES A CHANCE FOR A FEW SHOWERS LATE FRIDAY...AGAIN MAINLY OFFSHORE. THE COASTAL LOW FINALLY SHIFTS EAST AS A SIGNIFICANT SYSTEM DEEPENS AND CLOSES OFF OVER THE MIDWEST. THIS WILL DRIVE A COLD FRONT THROUGH NEW ENGLAND MIDDAY SATURDAY INTO SUNDAY MORNING. THIS IS A MUCH SHARPER BOUNDARY AND RAINFALL AMOUNTS SHOULD BE HEAVIER AND TOP AN INCH IN THE HEAVIER CELLS. ANTECEDENT CLOUD COVER WILL LIMIT INSTABILITY BUT WE SHOULD SEE SOME THUNDER WITH -26 C ASSOCIATED WITH THE CORE. COLDER AND DRIER AIR ARRIVES BEHIND THIS FRONT AND ESPECIALLY AFTER ANOTHER COLD FRONT MOVES THROUGH NEXT TUESDAY. && .AVIATION /22Z TUESDAY THROUGH SUNDAY/... SHORT TERM /THROUGH WEDNESDAY NIGHT/...MAINLY MVFR CONDITIONS THIS EVENING...LOWERING TO IFR TONIGHT AND FOR A GOOD PORTION OF WEDNESDAY AND WEDNESDAY NIGHT AS MOIST NORTHEAST FLOW CONTINUES. LONG TERM...WRAP AROUND MOISTURE WILL KEEP FOG...LOW CLOUDS AND PERHAPS DRIZZLE AROUND THE COAST AND AS FAR INLAND AS KAUG THURSDAY MORNING. MVFR CIGS WILL LINGER ALONG THE MIDCOAST THROUGH FRIDAY. LOWER CEILINGS IN HEAVY SHOWERS WITH SOME TSRA EXPECTED SATURDAY INTO SUNDAY EARLY AFTERNOON...IMPROVING TO VFR WEST TO EAST. && .MARINE... SHORT TERM /THROUGH WEDNESDAY NIGHT/...THE NORTHEAST FLOW WILL ONCE INCREASE BY LATER TONIGHT WITH GUSTS TO NEAR 25 KT AND BUILDING SEAS. AN SCA HAS BEEN REISSUED FOR LATE TONIGHT AND WEDNESDAY FOR AREAS OUTSIDE THE BAYS. LONG TERM...SEAS WILL BE 5-7 FT THURSDAY THROUGH SUNDAY OUTSIDE THE BAYS AS A SERIES OF FRONTAL SYSTEMS CROSS THE WATERS. WINDS MAY OCCASIONALLY GUST NEAR 25 KTS. WE WILL LIKELY ISSUE SMALL CRAFTS DURING THESE TIMES. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...NONE. NH...NONE. MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 8 PM EDT WEDNESDAY FOR ANZ150-152-154. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
945 AM EDT TUE SEP 30 2014 .SYNOPSIS... WEAK LOW PRESSURE WILL CROSS THE REGION TODAY. WARM AND DRY CONDITIONS WILL FOLLOW UNTIL THE PASSAGE OF A FRIDAY COLD FRONT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH 945AM UPDATE...HAVE CONTINUED TO EXPAND COVERAGE OF LIKELY AND CATEGORICAL POPS. REGARDLESS OF WHAT THE HRRR AND RAP ARE CURRENTLY DEPICTING...LINE OF SHOWERS AND ISOLATED THUNDERSTORMS CONTINUES TO HOLD TOGETHER. HOWEVER...12Z PIT SOUNDING SHOWS A LOT OF DRY AIR...WHICH IS LIKELY THE REASON THAT MODELS SHOW A WEAKENING TREND IN SHOWERS LATER TODAY AS THE AIR MASS MOVES FARTHER EAST. IN ADDITION...THE STORM PREDICTION CENTER HAS EXPANDED ITS AREA FOR A MARGINAL HAIL THREAT...AND HAVE LIKEWISE EXPANDED THE AREA IN THE FORECAST THAT MENTIONS A SMALL HAIL THREAT. 4AM DISCUSSION FOLLOWS. WEAK BOUNDARY WITH STRONG UPPER LEVEL SUPPORT WILL SLOWLY CROSS THE AREA TODAY. STILL HAVING A TOUGH TIME GETTING A HANDLE ON HOW MUCH PRECIPITATION THIS SYSTEM WILL PRODUCE. THE BEST UPPER LEVEL SUPPORT WILL BE WITH THE MAIN 50H LOW WHICH WILL TRAIL BEHIND THE FRONT AND MOVE INTO NE OHIO LATE THIS AFTERNOON. THE ATMOSPHERIC MOISTURE NEVER REALLY GETS LINED UP AS THE MID AND UPPER LEVEL MOISTURE MOVES IN AHEAD OF THE 50H LOW...BUT THE LOW LEVEL MOISTURE HANGS BACK WITH THE MAIN SHORTWAVE ROTATING AROUND THE UPPER LEVEL SYSTEM. FORECAST SOUNDINGS ARE SHOWING A DRY LAYER UP TO AROUND 5000 FT THROUGH THE ENTIRE DAY...MAKING IT DIFFICULT FOR SHOWERS TO REACH THE GROUND. WILL LEAVE IN CHANCE POPS FOR TODAY WITH THE HIGHEST PROBABILITY FOR MEASURABLE RAIN ACROSS THE NORTH CLOSER TO THE UPPER LEVEL LOW. IF THE LOW LEVELS ARE ABLE TO SATURATE TODAY THEN MORE WIDESPREAD SHOWER ACTIVITY IS POSSIBLE. IN ADDITION...COLD POOL ALOFT...WITH PASSING 50H...LOW MAY PROVIDE ENOUGH ELEVATED INSTABILITY THAT AN ISOLATED STORM COULD DEVELOP THIS AFTERNOON. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... THE ENTIRE SYSTEM WEAKENS THIS EVENING. THE 50H LOW OPENS UP AND WHATS LEFT OF THE SURFACE BOUNDARY DRIFTS INTO EASTERN PA. UPPER LEVEL WAVES OF ENERGY WILL SWING AROUND THE BACKSIDE OF THE EXITING 50H LOW SO WILL LEAVE IN SLIGHT CHANCE/LOW CHANCE POPS IN THE FAR EAST FOR A PORTION OF THE EVENING HOURS. UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE LOW ON THURSDAY... PROVIDING SUNSHINE AND WARM TEMPERATURES. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... STILL SEEING SOME MINOR TIMING ISSUES WITH FRONTAL PASSAGE ON FRIDAY. LATEST NAM IS SLOWING EVERYTHING DOWN...GFS IS THE MOST PROGRESSIVE AND THE 12Z ECMWF IS SOMEWHERE IN BETWEEN. FRIDAY DOES APPEAR LIKE A GOOD CHANCE FOR SOME MUCH NEEDED WIDESPREAD RAIN. MUCH COLDER AIR WILL SETTLE IN FOR THE WEEKEND. OVERALL THE PATTERN WILL SHIFT FROM THE QUIET WE HAVE EXPERIENCED OVER THE LAST TWO OR SO WEEKS...TO A MORE ACTIVE AND COOLER PATTERN. && .AVIATION /14Z TUESDAY THROUGH SATURDAY/... CLOSED LOW ALOFT WILL ROTATE SOUTHEAST TOWARD LAKE ERIE THIS AFTERNOON WITH A WEAK COLD FRONT TO FOLLOW. BAND OF SHOWERS ACROSS OHIO THIS MORNING CLOSER TO UPPER LEVEL SUPPORT. MODELS SHOWING RATHER WIDESPREAD COVERAGE FOR SHOWERS THIS AFTERNOON BUT NOT WHOLLY CONVINCED OF THIS BASED ON MODEL SOUNDINGS WITH AVAILABLE MOISTURE. VCSH REMAINS MOST PORTS THIS AFTERNOON WITH RESTRICTIONS POSSIBLE MAINLY AT KFKL AND KDUJ. OUTLOOK.../WEDNESDAY THROUGH SATURDAY/... THE NXT CHC FOR WIDESPREAD RESTRICTIONS WL COME WITH A FRIDAY CDFNT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
755 AM EDT TUE SEP 30 2014 .SYNOPSIS... WEAK LOW PRESSURE WILL CROSS THE REGION TODAY. WARM AND DRY CONDITIONS WILL FOLLOW UNTIL THE PASSAGE OF A FRIDAY COLD FRONT. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... WITH 8AM UPDATE...HAVE ADDED SOME LIKELY POPS IN THE NORTHWESTERN CORNER OF THE FORECAST AREA. HRRR AND RAP MODELS SHOW THE LINE OF SHOWERS CURRENTLY IN OHIO AS BEING MORE SCATTERED IN NATURE BY THE AFTERNOON...BUT STILL THINK THE LINE WILL MANAGE TO HOLD TOGETHER AT LEAST INTO MERCER COUNTY. ALSO ADDED THUNDER INTO THE FORECAST SLIGHTLY EARLIER WITH SOME ISOLATED STRIKES ALREADY OCCURRING IN NORTH CENTRAL OHIO. PREVIOUS DISCUSSION FOLLOWS. WEAK BOUNDARY WITH STRONG UPPER LEVEL SUPPORT WILL SLOWLY CROSS THE AREA TODAY. STILL HAVING A TOUGH TIME GETTING A HANDLE ON HOW MUCH PRECIPITATION THIS SYSTEM WILL PRODUCE. THE BEST UPPER LEVEL SUPPORT WILL BE WITH THE MAIN 50H LOW WHICH WILL TRAIL BEHIND THE FRONT AND MOVE INTO NE OHIO LATE THIS AFTERNOON. THE ATMOSPHERIC MOISTURE NEVER REALLY GETS LINED UP AS THE MID AND UPPER LEVEL MOISTURE MOVES IN AHEAD OF THE 50H LOW...BUT THE LOW LEVEL MOISTURE HANGS BACK WITH THE MAIN SHORTWAVE ROTATING AROUND THE UPPER LEVEL SYSTEM. FORECAST SOUNDINGS ARE SHOWING A DRY LAYER UP TO AROUND 5000 FT THROUGH THE ENTIRE DAY...MAKING IT DIFFICULT FOR SHOWERS TO REACH THE GROUND. WILL LEAVE IN CHANCE POPS FOR TODAY WITH THE HIGHEST PROBABILITY FOR MEASURABLE RAIN ACROSS THE NORTH CLOSER TO THE UPPER LEVEL LOW. IF THE LOW LEVELS ARE ABLE TO SATURATE TODAY THEN MORE WIDESPREAD SHOWER ACTIVITY IS POSSIBLE. IN ADDITION...COLD POOL ALOFT...WITH PASSING 50H...LOW MAY PROVIDE ENOUGH ELEVATED INSTABILITY THAT AN ISOLATED STORM COULD DEVELOP THIS AFTERNOON. && .SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/... THE ENTIRE SYSTEM WEAKENS THIS EVENING. THE 50H LOW OPENS UP AND WHATS LEFT OF THE SURFACE BOUNDARY DRIFTS INTO EASTERN PA. UPPER LEVEL WAVES OF ENERGY WILL SWING AROUND THE BACKSIDE OF THE EXITING 50H LOW SO WILL LEAVE IN SLIGHT CHANCE/LOW CHANCE POPS IN THE FAR EAST FOR A PORTION OF THE EVENING HOURS. UPPER LEVEL RIDGE WILL MOVE IN BEHIND THE LOW ON THURSDAY... PROVIDING SUNSHINE AND WARM TEMPERATURES. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... STILL SEEING SOME MINOR TIMING ISSUES WITH FRONTAL PASSAGE ON FRIDAY. LATEST NAM IS SLOWING EVERYTHING DOWN...GFS IS THE MOST PROGRESSIVE AND THE 12Z ECMWF IS SOMEWHERE IN BETWEEN. FRIDAY DOES APPEAR LIKE A GOOD CHANCE FOR SOME MUCH NEEDED WIDESPREAD RAIN. MUCH COLDER AIR WILL SETTLE IN FOR THE WEEKEND. OVERALL THE PATTERN WILL SHIFT FROM THE QUIET WE HAVE EXPERIENCED OVER THE LAST TWO OR SO WEEKS...TO A MORE ACTIVE AND COOLER PATTERN. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... IFR FOG ALREADY HAS DEVELOPED IN THE USUAL VALLEY LOW LYING AREAS AND IS INCLUDED IN TERMINALS EARLY THIS MORNING...WITH PATCHY MVFR ELSEWHERE. CLOSED LOW ALOFT WILL ROTATE SOUTHEAST TOWARD LAKE ERIE THIS AFTERNOON WITH A WEAK COLD FRONT TO FOLLOW. BAND OF SHOWERS ACROSS MICHIGAN THIS MORNING CLOSER TO UPPER LEVEL SUPPORT. MODELS SHOWING RATHER WIDESPREAD COVERAGE FOR SHOWERS THIS AFTERNOON BUT NOT WHOLLY CONVINCED OF THIS BASED ON MODEL SOUNDINGS WITH AVAILABLE MOISTURE. VCSH REMAINS MOST PORTS THIS AFTERNOON WITH RESTRICTIONS POSSIBLE MAINLY AT KFKL AND KDUJ. OUTLOOK.../TUESDAY NIGHT THROUGH SATURDAY/... THE NXT CHC FOR WIDESPREAD RESTRICTIONS WL COME WITH A FRIDAY CDFNT. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...NONE. OH...NONE. PA...NONE. WV...NONE. && $$
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
1159 PM EDT WED OCT 1 2014 .AVIATION... //DISCUSSION... LIGHT SOUTHEAST FLOW CONTINUES TO FUNNEL LOW LEVEL MOISTURE INTO THE AREA AND FOG/STRATUS IS ALREADY RE-FORMING LATE THIS EVENING WITH A LARGER AREA OF IFR/LIFR CIGS ALSO SPREADING BACK WEST TOWARDS REGION FROM ONTARIO/LAKE ERIE. WILL MAINTAIN IFR CIGS OVERNIGHT WITH VSBYS ALSO FALLING INTO THE 1-2SM RANGE INTO EARLY THURSDAY MORNING. WITH ANY LUCK...CIRRUS STREAMING INTO THE AREA WILL KEEP WIDESPREAD DENSE FOG AT BAY OVERNIGHT. CONDITIONS WILL IMPROVE WITHIN INCREASED SOUTH TO SOUTHEAST FLOW ON THURSDAY IN ADVANCE OF APPROACHING TROUGH. CIGS WILL LIFT TO VFR...MAINLY FROM LEAD MOISTURE SHIFTING IN FROM THE WEST WITH THIS NEXT SYSTEM. //DTW THRESHOLD THREATS... * MEDIUM TO HIGH CONFIDENCE IN CEILINGS BELOW 5000 FEET OVERNIGHT INTO EARLY THURSDAY MORNING...WITH LOWER CONFIDENCE ON THURSDAY. * LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM FROM ABOUT 06Z-14Z. && .PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014 SHORT TERM...TONIGHT SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET WITH NOCTURNAL COOLING. NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS. LONG TERM... THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL AMPLIFICATION OVER THE NEXT 48 HOURS. THIS PROCESS WILL COMMENCE AS STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD. STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE WORK WEEK. THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD. A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO THE EAST. THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED CLOUD DECK DURING THE FIRST HALF OF THE DAY. DESPITE THE WARMING THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY. IN ACCORDANCE WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH HIGHS OF LOW TO MID 70S. TANGIBLE FORCING THROUGH THE DAYLIGHT PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE ENERGY FUNNELING THROUGH THE MEAN SW FLOW. THERE REMAINS THE POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES. LOW CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE OF UNCERTAINTY. THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY NIGHT. THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD /50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY. THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN PRECIPITATION CHANCES COMMENCING DURING THIS TIME. DEEPEST ASCENT IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL ENVIRONMENT. EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED INSTABILITY. SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON FRIDAY. THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY AFTERNOON. A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY NIGHT. AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME GUSTS OVER 20 MPH BEING COMMON. MARINE... SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR. THIS WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY. THE POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY NEAR THE SURFACE. THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME. A GUSTY WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE LAKES REGION. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DG SHORT TERM...CB LONG TERM....MR/MM MARINE.......MR YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS DETROIT/PONTIAC MI
734 PM EDT WED OCT 1 2014 .AVIATION... //DISCUSSION... RADIATIONAL COOLING WILL BE DECENT TONIGHT NOW THAT SKIES HAVE BECOME PARTLY CLOUDY. THIS...COMBINED WITH CONTINUED LIGHT FLOW FROM THE SOUTHEAST WILL MOST LIKELY PROMOTE SOME FOG DEVELOPMENT AFTER MIDNIGHT INTO EARLY THURSDAY MORNING. CONFIDENCE IN COVERAGE AND TIMING REMAIN LOW AT THIS POINT. ANY FOG/LOW STRATUS THAT DOES DEVELOP WILL DISSIPATE AS LOWER/MID VFR CIGS BETWEEN 6-12KFT MOVE INTO THE AREA IN ADVANCE OF APPROACHING TROUGH. //DTW THRESHOLD THREATS... * LOW CONFIDENCE IN CEILINGS AOB 200 FT AND/OR VSBYS AOB 1/2SM AFTER 2 AM. && .PREV DISCUSSION...ISSUED 354 PM EDT WED OCT 1 2014 SHORT TERM...TONIGHT SOUTHEASTERN MICHIGAN WILL REMAIN UNDER THE SPELL OF THE STRONG SURFACE ANTICYCLONE TONIGHT OVER PORTIONS OF EASTERN QUEBEC AND CANADIAN MARITIMES WITH A SUBSTANTIAL SURFACE RIDGE EXTENDING BACK INTO THE GREAT LAKES REGION. THIS FEATURE WILL CONTINUE TO DIRECT A SOUTHEASTERLY LOW TROPOSPHERE FEED INTO THE STATE DESPITE A WEAK MIDLEVEL RIDGE SLIDING OVERHEAD. THIS UPPER LEVEL RIDGE WILL ESSENTIALLY CAUSE THE PATTERN LOCALLY TO REMAIN STAGNANT THROUGH THE OVERNIGHT...DISALLOWING MUCH IN THE WAY OF ADVECTIONS OR AIRMASS TURNOVER. CLOUD TRENDS THIS AFTERNOON HAVE BEEN SLUGGISH IN MANY AREAS WITH A TRANSITION FROM STRATUS TO CUMULOFORM. THERE HAS BEEN A RAPID CLEARING TREND OVER PORTIONS OF SOUTH CENTRAL LOWER MICHIGAN BUT SUSPECT THIS TO SLOW DOWN AND NOT MAKE MUCH INROADS TO SOUTHEASTERN MICHIGAN BEFORE SUNDOWN. INSTEAD...EXPECT VERTICAL CLOUD CIRCULATIONS TO DEEPEN YET OVER THE NEXT 4 HOURS WHICH WILL SUPPORT GREATER CONVECTIVE ELEMENT SPACING AND INTRODUCE GREATER CLOUD SCALE SUBSIDENCE AND ENTRAINMENT OF DRY AIR ALOFT. THIS SHOULD SET THE STAGES FOR A RAPID CLEARING TREND IN MANY AREAS POST SUNSET WITH NOCTURNAL COOLING. NAM AND LATEST HRRR NWP IS VERY SUPPORTIVE OF FOG TONIGHT WITH A MUCH BETTER PROFILE FOR NEAR SURFACE SATURATION IN COMPARISON TO YESTERDAY MORNING. GIVEN THE AFOREMENTIONED LACK OF ADVECTIONS ALONG WITH THE CONTINUATION OF GREENUP ACROSS THE AREA...HIGH AMBIENT MOISTURE IN THE BACKGROUND SHOULD SUPPORT FOG FAIRLY EARLY TONIGHT...I.E. SHORTLY AFTER MIDNIGHT. EXPECTATIONS ARE FOR FOG TO DEVELOP ACROSS PORTIONS OF ONTARIO...PORT HURON AND THE EASTERN THUMB BEFORE SPREADING WESTWARD. MODELS ARE ALSO SHOWING A SIGNAL THAT AREAS SOUTH AND EAST OF THE TERRAIN IN HIGHER SURFACE PRESSURE AREAS COULD VERY WELL BE A FAVORABLE ZONE FOR FOG DEVELOPMENT. GIVEN THERMODYNAMIC STRUCTURE...DENSE FOG WILL BE POSSIBLE. CONFIDENCE IS NOT 100 PERCENT AS IT SELDOM IS...AND WILL GIVE LATER SHIFTS THE FLEXIBILITY ON ANY POSSIBLE HEADLINE DECISIONS. LONG TERM... THE NORTHERN PORTION OF THE EXISTING LONGWAVE TROUGHING NOW ENCOMPASSING MUCH OF THE WESTERN CONUS WILL UNDERGO SUBSTANTIAL AMPLIFICATION OVER THE NEXT 48 HOURS. THIS PROCESS WILL COMMENCE AS STRONG SHORTWAVE ENERGY AND AN ATTENDANT 140 KT UPPER JET CORE CURRENTLY OVER BRITISH COLUMBIA DIG INTO THE LOWER HEIGHT FIELD. STRENGTHENING DYNAMICS ATTENDANT TO A LEAD WAVE UNDERCUTTING THE AMPLIFYING TROUGH WILL BRING A PERIOD OF ACTIVE WEATHER TO END THE WORK WEEK. THE DEEPENING PROCESS WILL THEN LEAVE A CLOSED LOW CONFIGURATION CENTERED JUST TO THE NORTH FOR THE UPCOMING WEEKEND...SPELLING A CONSIDERABLY COLDER AND UNSETTLED PERIOD. A DEEPER SOUTHWESTERLY FLOW TAKES HOLD ON THURSDAY AS THE GRADUALLY EXPANDING HEIGHT FALLS NUDGE THE EXISTING UPPER RIDGE TO THE EAST. THIS PROCESS WILL MIX OUT ANY LINGERING FOG THROUGH LATE MORNING...WITH THE ENSUING INCREASE IN MID LEVEL WARM AIR AND THETA-E ADVECTION PROMPTING A STEADY THICKENING OF A HIGH BASED CLOUD DECK DURING THE FIRST HALF OF THE DAY. DESPITE THE WARMING THERMAL PROFILE...A LINGERING SOUTHEAST SURFACE WIND AND LIMITED MIXING DEPTH WILL MUTE THE OVERALL RESPONSE SLIGHTLY. IN ACCORDANCE WITH THE GOING FORECAST...WILL CONTINUE TO TEMPER EXPECTATIONS WITH HIGHS OF LOW TO MID 70S. TANGIBLE FORCING THROUGH THE DAYLIGHT PERIOD REMAINS LESS DEFINED LOCALLY...THE AREA LARGELY REMOVED TO THE EAST FROM THE MAIN CORRIDOR OF ASCENT LOCKED ONTO THE THETA-E RIDGE AND PRIMARY TRAJECTORY OF ANY LOWER AMPLITUDE SHORTWAVE ENERGY FUNNELING THROUGH THE MEAN SW FLOW. THERE REMAINS THE POTENTIAL FOR THIS AXIS TO CREEP FAR ENOUGH EAST TO SUPPORT SOME LIGHT SHOWER DEVELOPMENT...PARTICULARLY ACROSS THE TRI-CITIES. LOW CHANCE POPS REMAIN APPROPRIATE FOR THIS AREA GIVEN THE HIGH DEGREE OF UNCERTAINTY. THE INCREASING INTERACTION BETWEEN THE AFOREMENTIONED SOUTHERN WAVE EJECTING NORTHEAST OUT OF THE SOUTHERN PLAINS AND THE DEEPENING LOW ACROSS THE DAKOTAS WILL PROMPT RAPID SURFACE CYCLOGENESIS AND A STRENGTHENING OF THE ATTENDANT COLD FRONT UPSTREAM BY THURSDAY NIGHT. THE DOWNSTREAM PROPAGATION OF A STRENGTHENING WIND FIELD /50 KTS AT 850MB/ EMBEDDED WITHIN THE WARM SECTOR AND AT THE EDGE OF THE INBOUND LOWER HEIGHT FIELD WILL LIKELY PROMOTE AN EXPANSION IN PRECIPITATION COVERAGE THROUGHOUT THE MIDWEST BY LATE THURSDAY. THIS FORCING REMAINS FORECAST TO TRACK THROUGH SE MICHIGAN LATE THURSDAY NIGHT AND EARLY FRIDAY...A CORRESPONDING STEADY INCREASE IN PRECIPITATION CHANCES COMMENCING DURING THIS TIME. DEEPEST ASCENT IN PLACE DURING THE FIRST HALF OF FRIDAY...A PERIOD OF SOLID UPPER DIVERGENCE AND CVA WORKING INTO A MOISTENING PRE-FRONTAL ENVIRONMENT. EXISTING MID LEVEL INSTABILITY CERTAINLY SUFFICIENT TO SUPPORT A THUNDER MENTION...A FEW STRONGER GUSTS A POSSIBILITY GIVEN THE WIND FIELD SHOULD BEST CORES CAPITALIZE ON THE LIMITED INSTABILITY. SURFACE LOW DEEPENS TO 993 MB AS IT TRACKS NORTH OF LAKE SUPERIOR ON FRIDAY. THE OVERALL AMPLITUDE OF THIS SYSTEM CONTINUES TO FAVOR A SLOWER DOWNSTREAM PROGRESSION OF THE MAIN HEIGHT FALL CENTER...WITH THE CORRESPONDING COLD FRONTAL PASSAGE NOW EXPECTED EARLY FRIDAY AFTERNOON. A TRAILING PERIOD OF CVA AS THE STRONGER HEIGHT FALLS COMMENCE AND COLD AIR ADVECTION ENSUES WILL SUSTAIN SCATTERED TO NUMEROUS POST-FRONTAL SHOWER PRODUCTION LATE FRIDAY AND FRIDAY NIGHT. AMPLIFIED UPPER LEVEL TROUGH WILL BE SUSTAINED BY A 130 TO 140KT JET THAT DIPS SOUTH OF THE GREAT LAKES INTO THE TENNESSEE VALLEY THROUGH THE WEEKEND. THE UPPER LOW BECOMES CLOSED AT 500MB...BOTTOMING OUT AROUND 538 DAM. EVEN AFTER SYNOPTIC RAIN ENDS ON SATURDAY...STEEP LAPSE RATES IN PLACE WILL ALLOW FOR A 20 TO 30 PERCENT CHANCE FOR RAIN SHOWERS EACH DAY IN THE EXTENDED PERIOD. STRONG GEOSTROPHIC WIND COMPONENT WILL ALSO BE IN PLACE MOST OF THE PERIOD WITH DAYTIME GUSTS OVER 20 MPH BEING COMMON. MARINE... SOUTHEAST WINDS WILL STEADILY INCREASE THURSDAY AND THURSDAY NIGHT AS STRENGTHENING LOW PRESSURE TRACKS ACROSS LAKE SUPERIOR. THIS WILL RESULT IN A PERIOD OF GUSTY CONDITIONS FOR PORTIONS OF SOUTHERN AND CENTRAL LAKE HURON BY LATE THURSDAY NIGHT AND EARLY FRIDAY. THE POTENTIAL EXISTS FOR SOME GUSTS OF UP TO 30 KNOTS...ALTHOUGH THE ARRIVAL OF WARMER AIR WILL MAINTAIN A HIGHER DEGREE OF STABILITY NEAR THE SURFACE. THERE WILL BE A SLIGHT CHANCE FOR THUNDERSTORMS AS WIDESPREAD SHOWERS MOVE THROUGH DURING THIS TIME. A GUSTY WESTERLY WIND FOR THE WEEKEND AS SEASONABLY COLD AIR OVERSPREADS THE LAKES REGION. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...NONE. LAKE HURON...NONE. LAKE ST CLAIR...NONE. MI WATERS OF LAKE ERIE...NONE. && $$ AVIATION.....DG SHORT TERM...CB LONG TERM....MR/MM MARINE.......MR YOU CAN OBTAIN YOUR LATEST NATIONAL WEATHER SERVICE FORECASTS ONLINE AT WWW.WEATHER.GOV/DETROIT (ALL LOWER CASE).
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EDT TUE SEP 30 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 311 PM EDT TUE SEP 30 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SHARP UPR RDG EXTENDING FM THE MID MS RIVER VALLEY N INTO NW ONTARIO...SUPPORTING SFC HI PRES JUST N OF LK SUP. ALTHOUGH THE MID TROP IS QUITE DRY... WITH 12Z H5 DEWPT DEPRESSIONS AS HI AS 45C AT MPX AND QUAD CITIES... LINGERING LLVL MSTR TO THE S OF THE HI CENTER AND BLO SHARP SUBSIDENCE INVRN ARND H9-925 CAUSED QUITE A BIT OF LO CLD TO PERSIST OVER THE UPR LKS THRU THE MRNG. DAYTIME HEATING THAT HAS CAUSED THE LCL TO RISE THRU THE SLOWLY SINKING INVRN BASE PER FCST SDNGS IS RESULTING IN STEADY BREAKUP OF THE LO CLD EARLY THIS AFTN. THE LO CLDS HAVE BEEN MOST RESILIENT OVER THE CENTRAL...WHERE LLVL NE WIND IS UPSLOPING. LOOKING UPSTREAM...A VIGOROUS NEGATIVELY TILTED SHRTWV IS LIFTING NNEWD THRU THE NRN PLAINS. DESPITE THE MID LVL DRY AIR IN PLACE...SOME SHOWERS/TS IN THE RATHER NARROW WARM CONVEYOR BELT ASSOCIATED WITH THIS DISTURBANCE ARE MOVING INTO SW MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON CLD TRENDS. FCST CONCERNS ON WED SHIFT TO THE POTENTIAL FOR SOME SHOWERS IN THE INCRSG SLY FLOW/ISENTROPIC ASCENT TO THE E OF SHRTWV MOVING THRU THE NRN PLAINS INTO SCENTRAL CANADA. TNGT...ALTHOUGH THE LO CLDS WL CONTINUE TO DISSIPATE INTO THE EVNG WITH THE IMPACTS OF DAYTIME HEATING/MIXING...NOCTURNAL COOLING AND VEERING WINDS TO THE S THAT WL BRING A RETURN OF MOISTER H95-9 AIR SHOULD RESULT IN MORE LO CLDS. NOT OUT OF THE QUESTION THERE COULD BE SOME DRIZZLE OVER THE CENTRAL WHERE EXPECTED SSE WIND WL UPSLOPE OFF LK MI. THE ONE EXCEPTION WL BE OVER THE W...WHERE THE S WIND WL DOWNSLOPE AND PREVENT/LIMIT THE REFORMATION OF THE LO CLDS. OTRW... SOME MID/HI CLDS ON THE ERN FLANK OF THE WARM CONVEYOR BELT MSTR RIBBON MOVING E THRU WL INVADE THE W OVERNGT. THE COMBINATION OF LINGERING LO CLDS AND/OR INCRSG SLY FLOW WITH H925 WINDS INCRSG UP TO 20-30 KTS BY 12Z WED WL LIMIT THE DIURNAL TEMP FALL. BUT TEMPS SHOULD STILL FALL INTO THE 30S AT SOME OF THE INTERIOR COLD SPOTS THAT SEE MOCLR SKIES FOR A TIME. WED...ALTHOUGH THE PASSAGE OF SHRTWV/ACCOMPANYING DPVA AND DEEP LYR QVECTOR CNVGC WELL TO THE W THRU MANITOBA WL LIMIT THE PCPN POTENTIAL OVER UPR MI...RATHER NARROW WARM CONVEYOR BELT MSTR RIBBON AND AREA OF H85-5 QVECTOR CNVGC/UPR DVGC AND BAND OF H85-7 FGEN IN RRQ OF 80KT H3 JET MAX LIFTING NNEWD THRU NW ONTARIO WL BRING THE THREAT OF SHOWERS TO THE W IN THE AFTN. CONSIDERING THE STRONG DYNAMIC SUPPORT AND APPRECIABLE DEEP MOISTENING THAT IS FCST TO RAISE PWAT NEAR 1.5 INCHES /UP TO 200 PCT OF NORMAL/ BY 00Z THU...HI LIKELY POPS SEEM APPROPRIATE OVER THE FAR W. ALTHOUGH THE MID LVLS OVER THE E WL REMAIN DRY...FCST SDNGS INDICATE LO CLDS WL PERSIST MOST OF THE DAY IN THAT AREA AND LIMIT THE DAYTIME TEMP RECOVERY. BUT WITH STRENGTHENING SLY FLOW BRINGING A RETURN OF H85 TEMPS AS HI AS 12-13C...MAX TEMPS WL RISE ABV NORMAL...ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LK SUP. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 425 PM EDT TUE SEP 30 2014 BY 00Z THURSDAY THE AREA WILL BE DOMINATED BY SW FLOW ALOFT...WITH MOISTURE STREAMING N FROM THE OPEN GULF OF MEXICO. THE INITIAL SHORTWAVE WILL BE CROSSING THE CWA. WITH STEADY S WINDS AND 850MB TEMPS NEAR 11C...EXPECT THE FCST LOWS IN THE UPPER 40S TO MID 50S TO HOLD. WHILE THIS INITIAL BAND OF SHOWERS WILL PRODUCE A QUARTER TO HALF AN INCH OF LIQUID...THE BEST CHANCE OF WIDESPREAD PRECIP WILL HOLD OFF UNTIL THURSDAY NIGHT. THIS WILL BE WHEN THE 500MB LOW SET UP ACROSS MAINLY ONTARIO DIVES ACROSS MN...AND THE SFC LOW ACROSS MO/IA QUICKLY DEEPENS TO AROUND 998MB ACROSS THE W HALF OF UPPER MI LATE THURSDAY EVENING...AND TO AROUND 988MB BY DAYBREAK FRIDAY OVER N LAKE SUPERIOR. LOOK FOR WINDS TO RAPIDLY INCREASE OVER W LAKE SUPERIOR AND FAR W UPPER MI OVERNIGHT. THE SFC LOW WILL SHIFT UP ACROSS JAMES BY FRIDAY AFTERNOON AND EVENING...ALLOWING MUCH COOLER AIR TO SURGE INTO THE REGION. THE GFS LOOKS TO BE THE STRONGEST WIND WISE BY FRIDAY AFTERNOON...WITH GALE FORCE GUSTS ACROSS THE KEWEENAW PENINSULA THROUGH THE E HALF OF LAKE SUPERIOR TO GRAND MARAIS. WHILE THIS MAY BE POSSIBLE...LESS FAVORABLE WIND DIRECTIONS OFF THE ECMWF AND NAM ARE NOT BACKING THIS UP QUITE YET. GALES WILL BE STILL BE POSSIBLE SOMETIME THIS PERIOD...BUT WILL KEEP MORE OF A BLENDED SOLUTION FOR THE TIME BEING UNTIL MODELS COME MORE IN LINE. WILL KEEP THE TS POTENTIAL IN THROUGH FRIDAY NIGHT...NO HIGHER THAN SLIGHT CHANCE...AND STILL MAINLY KEEPING IT OVER UPPER MI/LAKE MI. THE SFC LOW WILL NOT EXIT FAST...AND WILL KEEP A TROUGH ACROSS THE UPPER GREAT LAKES THROUGH SUNDAY. THE 500MB LOW WILL SWING ACROSS UPPER MI FRIDAY NIGHT THROUGH SATURDAY...WITH THE COLDEST AIR OF -23 TO -29C AT 500MB ROTATING ACROSS UPPER MI AND WI. WE ARE BACK TO THAT TIME OF YEAR WHERE COOL NIGHTS...LOW LEVEL MOISTURE...AND FAVORABLE UPSLOPE CONDITIONS OFF OF THE WARM LAKES WILL HELP PRODUCE A FEW SNOW SHOWERS. THIS SHOULD BE THE CASE FRIDAY NIGHT AND AGAIN SATURDAY NIGHT INLAND FROM THE GREAT LAKES. THE SFC RIDGE WILL ATTEMPT TO BUILD BACK ACROSS THE UPPER GREAT LAKES MONDAY INTO MONDAY EVENING. WITH A LESS FAVORABLE WIND DIRECTION...THIS SHOULD BE THE DRIEST PERIOD DURING THE LONG TERM. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 132 PM EDT TUE SEP 30 2014 DAYTIME HEATING/MIXING WL ALLOW LO CLDS AT SAW AND IWD TO BREAK UP THIS AFTN WITH A PERIOD OF VFR CONDITIONS INTO AT LEAST THIS EVNG. ALTHOUGH CMX MAY SEE SOME SC/LOWER CIGS EARLY THIS AFTN ON THE NRN FRINGE OF SLOWLY DISSIPATING MAIN LO CLD AREA TO THE S...EXPECT VFR CONDITIONS TO PREDOMINATE THERE INTO AT LEAST THIS EVNG. ONCE HI PRES IN ONTARIO SHIFTS FARTHER TO THE E TNGT AND A LO PRES TROF APRCHS FM THE W...THE LLVL WINDS WL SHIFT TO A MORE S DIRECTION. IN THE PRESENCE OF NOCTURNAL COOLING AND THE RETURN OF MOISTER LLVL AIR...EXPECT LO CLDS/IFR CONDITIONS TO DVLP AT SAW. DOWNSLOPE NATURE OF THIS LLVL FLOW MAKES THE FCST AN ESPECIALLY TRICKY ONE FOR CMX AND IWD...SO INCLUDED JUST A SCT DECK FOR NOW. ANY LO CLDS THAT DVLP TNGT SHOULD DISSIPATE ON WED AT CMX/IWD WITH DAYTIME HEATING...BUT THESE CLDS WL BE MORE RESILIENT AT SAW EVEN IF THE CIG HGT DOES LIFT ABV 1K FT INTO THE MVFR RANGE BY NOON. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 353 PM EDT TUE SEP 30 2014 HIGH PRESSURE OF OVER N ONTARIO WILL MOVE E TO THE CANADIAN MARITIMES BY WEDNESDAY EVENING. MEANWHILE...LOW PRESSURE OVER WESTERN NE WILL LIFT ACROSS S MANITOBA WEDNESDAY MORNING...AND TO HUDSON BAY THURSDAY MORNING. A TROUGH ASSOCIATED WITH THE LOW WILL MOVE E...REACHING LAKE SUPERIOR ON THURSDAY. A LOW WILL FORM ALONG THIS TROUGH OVER THE UPPER MS VALLEY THURSDAY EVENING AND THEN DEEPEN AS IT LIFTS INTO N ONTARIO FRIDAY...AND TO HUDSON BAY FRIDAY NIGHT. IN ITS WAKE...HIGH PRESSURE OVER THE W PLAINS FRIDAY AFTERNOON WILL SETTLE OVER THE LOWER MS VALLEY SATURDAY INTO SUNDAY...AS A TROUGH EXTENDING FROM THE HUDSON BAY LOW LINGERS OVER N ONTARIO. A PERIOD OF NEAR GALES OUT OF THE W-NW WILL BE POSSIBLE FROM LATE FRIDAY AFTERNOON THROUGH THE DAY SATURDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...KF AVIATION...KC MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
353 PM EDT TUE SEP 30 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 311 PM EDT TUE SEP 30 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SHARP UPR RDG EXTENDING FM THE MID MS RIVER VALLEY N INTO NW ONTARIO...SUPPORTING SFC HI PRES JUST N OF LK SUP. ALTHOUGH THE MID TROP IS QUITE DRY... WITH 12Z H5 DEWPT DEPRESSIONS AS HI AS 45C AT MPX AND QUAD CITIES... LINGERING LLVL MSTR TO THE S OF THE HI CENTER AND BLO SHARP SUBSIDENCE INVRN ARND H9-925 CAUSED QUITE A BIT OF LO CLD TO PERSIST OVER THE UPR LKS THRU THE MRNG. DAYTIME HEATING THAT HAS CAUSED THE LCL TO RISE THRU THE SLOWLY SINKING INVRN BASE PER FCST SDNGS IS RESULTING IN STEADY BREAKUP OF THE LO CLD EARLY THIS AFTN. THE LO CLDS HAVE BEEN MOST RESILIENT OVER THE CENTRAL...WHERE LLVL NE WIND IS UPSLOPING. LOOKING UPSTREAM...A VIGOROUS NEGATIVELY TILTED SHRTWV IS LIFTING NNEWD THRU THE NRN PLAINS. DESPITE THE MID LVL DRY AIR IN PLACE...SOME SHOWERS/TS IN THE RATHER NARROW WARM CONVEYOR BELT ASSOCIATED WITH THIS DISTURBANCE ARE MOVING INTO SW MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON CLD TRENDS. FCST CONCERNS ON WED SHIFT TO THE POTENTIAL FOR SOME SHOWERS IN THE INCRSG SLY FLOW/ISENTROPIC ASCENT TO THE E OF SHRTWV MOVING THRU THE NRN PLAINS INTO SCENTRAL CANADA. TNGT...ALTHOUGH THE LO CLDS WL CONTINUE TO DISSIPATE INTO THE EVNG WITH THE IMPACTS OF DAYTIME HEATING/MIXING...NOCTURNAL COOLING AND VEERING WINDS TO THE S THAT WL BRING A RETURN OF MOISTER H95-9 AIR SHOULD RESULT IN MORE LO CLDS. NOT OUT OF THE QUESTION THERE COULD BE SOME DRIZZLE OVER THE CENTRAL WHERE EXPECTED SSE WIND WL UPSLOPE OFF LK MI. THE ONE EXCEPTION WL BE OVER THE W...WHERE THE S WIND WL DOWNSLOPE AND PREVENT/LIMIT THE REFORMATION OF THE LO CLDS. OTRW... SOME MID/HI CLDS ON THE ERN FLANK OF THE WARM CONVEYOR BELT MSTR RIBBON MOVING E THRU WL INVADE THE W OVERNGT. THE COMBINATION OF LINGERING LO CLDS AND/OR INCRSG SLY FLOW WITH H925 WINDS INCRSG UP TO 20-30 KTS BY 12Z WED WL LIMIT THE DIURNAL TEMP FALL. BUT TEMPS SHOULD STILL FALL INTO THE 30S AT SOME OF THE INTERIOR COLD SPOTS THAT SEE MOCLR SKIES FOR A TIME. WED...ALTHOUGH THE PASSAGE OF SHRTWV/ACCOMPANYING DPVA AND DEEP LYR QVECTOR CNVGC WELL TO THE W THRU MANITOBA WL LIMIT THE PCPN POTENTIAL OVER UPR MI...RATHER NARROW WARM CONVEYOR BELT MSTR RIBBON AND AREA OF H85-5 QVECTOR CNVGC/UPR DVGC AND BAND OF H85-7 FGEN IN RRQ OF 80KT H3 JET MAX LIFTING NNEWD THRU NW ONTARIO WL BRING THE THREAT OF SHOWERS TO THE W IN THE AFTN. CONSIDERING THE STRONG DYNAMIC SUPPORT AND APPRECIABLE DEEP MOISTENING THAT IS FCST TO RAISE PWAT NEAR 1.5 INCHES /UP TO 200 PCT OF NORMAL/ BY 00Z THU...HI LIKELY POPS SEEM APPROPRIATE OVER THE FAR W. ALTHOUGH THE MID LVLS OVER THE E WL REMAIN DRY...FCST SDNGS INDICATE LO CLDS WL PERSIST MOST OF THE DAY IN THAT AREA AND LIMIT THE DAYTIME TEMP RECOVERY. BUT WITH STRENGTHENING SLY FLOW BRINGING A RETURN OF H85 TEMPS AS HI AS 12-13C...MAX TEMPS WL RISE ABV NORMAL...ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LK SUP. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 433 AM EDT TUE SEP 30 2014 ATTENTION IN THE LONG TERM WILL BE ON THE UPPER TROUGH THAT WILL MOVE FROM THE INTERMOUNTAIN WEST AT 12Z WED INTO THE CWA AT 00Z SAT WHILE DEEPENING AND BECOMING NEGATIVELY TILTED...AS IS GENERALLY AGREED ON BY NWP. THE UPPER TROUGH THEN LOOKS TO CLOSE OFF INTO A LOW AS IT MOVES THROUGH THE REGION FRI NIGHT...BUT MODEL DISAGREEMENT INCREASES SIGNIFICANTLY AT THIS POINT WITH THE STRENGTH AND TRACK OF THE SYSTEM. GENERAL MODEL AGREEMENT DOES INCREASE SUN NIGHT INTO MON WITH MODELS SHOWING A DEEP TROUGH OVER THE ERN CONUS. ONE THING THAT CAN BE SAID WITH CERTAINTY IS THAT THE PATTERN WILL BE MORE ACTIVE THAN LAST WEEK. SHOWERS /POSSIBLY WITH SOME THUNDER/ IS STILL EXPECTED TO VERY GRADUALLY MOVE W TO E ACROSS THE CWA WED THROUGH THU DUE TO WAA/ISENTROPIC ASCENT AHEAD OF A SFC TROUGH/COLD FRONT. MAIN ISSUE TO POINT OUT FROM A CONFIDENCE STANDPOINT IS THAT SHORTWAVE ENERGY WILL PROBABLY EJECT FROM THE UPPER TROUGH TO THE W /AS SHOWN BY NWP/...BUT THE MODELS DO NO AGREE ON THE STRENGTH/TIMING/TRACK OF ANY ENERGY AND ASSOCIATED SFC CYCLOGENESIS. THERE WILL PROBABLY BE PERIODS OF HEAVIER PRECIP AND/OR GREATER PRECIP COVERAGE...BUT ACCURATELY TIMING THOSE OUT IS NOT POSSIBLE AT THIS TIME. HIGH TEMPS IN THE 60S LOOK TO MAKE A RETURN ON WED AND THU DUE TO THE WAA AND RESULTING WARM AIRMASS /850MB TEMPS OF 10-13C/. AS PREVIOUSLY MENTIONED...THE UPPER TROUGH TEARS INTO THE AREA THU NIGHT AND FRI...BRINGING A MUCH COLDER AIRMASS WITH IT. AT LEAST PORTIONS OF THE CWA SHOULD SEE 850MB TEMPS BELOW 0C BY THE END OF THE DAY FRI. GIVEN THE STRENGTH OF THE TROUGH AND MAGNITUDE OF RESULTING HEIGHT FALLS AS IT MOVES IN...PERIODS OF PRECIP DOES LOOK LIKE A GOOD BET THU NIGHT INTO FRI...ALTHOUGH AMOUNTS WILL BE DEPENDENT ON THE HIGHLY UNCERTAIN SFC LOW LEVEL FEATURES. SOME MODELS /MAINLY THE GFS AND NAM/ SHOW A DEEPER SFC LOW TRANSITING THE CWA THU NIGHT INTO FRI /AS THE GFS HAS SHOWN VARIOUS ITERATIONS OF FOR THE LAST SEVERAL RUNS/. IF THIS DOES OCCUR...GALES WOULD LIKELY OCCUR ACROSS PORTIONS OF THE GREAT LAKES...ALONG WITH MORE SUBSTANTIAL RAINFALL AMOUNTS. WHILE THIS IS NOT OUT OF THE QUESTION...THERE IS JUST TOO MUCH UNCERTAINTY AT THIS POINT TO ADD THIS SCENARIO TO THE FORECAST. PRECIP FRI NIGHT INTO SAT IS A BIT MORE CERTAIN SINCE IT WILL BE LESS DUE TO A SYNOPTIC SYSTEM AND MORE TO SUB ZERO 850MB TEMPS AND WNW-NW LOW LEVEL WINDS LEADING TO LAKE EFFECT PRECIP NEAR LAKE SUPERIOR. IN FACT...DEPENDING ON EXACTLY HOW COLD THE AIRMASS IS...SNOW IS CERTAINLY NOT OUT OF THE PICTURE FRI NIGHT INTO SAT NIGHT...BUT ACCUMULATING SNOW IS UNLIKELY /ESPECIALLY SIGNIFICANT ACCUMULATIONS/. DID ADD SNOW CHANCES TO THE FORECAST OVER HIGHER TERRAIN OF WRN UPPER MI FRI NIGHT INTO EARLY SAT AND FOR PORTIONS OF NWRN AND NERN UPPER MI SAT NIGHT. HIGH TEMPS BY SATURDAY LOOK TO BE IN THE UPPER 40S TO LOW 50S....WITH LOW TEMPS SAT NIGHT FROM THE UPPER 20S TO MID 30S. GOING COMPLETELY WITH MODEL CONSENSUS IDEA SUN AND MON GIVEN UNCERTAINTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 132 PM EDT TUE SEP 30 2014 DAYTIME HEATING/MIXING WL ALLOW LO CLDS AT SAW AND IWD TO BREAK UP THIS AFTN WITH A PERIOD OF VFR CONDITIONS INTO AT LEAST THIS EVNG. ALTHOUGH CMX MAY SEE SOME SC/LOWER CIGS EARLY THIS AFTN ON THE NRN FRINGE OF SLOWLY DISSIPATING MAIN LO CLD AREA TO THE S...EXPECT VFR CONDITIONS TO PREDOMINATE THERE INTO AT LEAST THIS EVNG. ONCE HI PRES IN ONTARIO SHIFTS FARTHER TO THE E TNGT AND A LO PRES TROF APRCHS FM THE W...THE LLVL WINDS WL SHIFT TO A MORE S DIRECTION. IN THE PRESENCE OF NOCTURNAL COOLING AND THE RETURN OF MOISTER LLVL AIR...EXPECT LO CLDS/IFR CONDITIONS TO DVLP AT SAW. DOWNSLOPE NATURE OF THIS LLVL FLOW MAKES THE FCST AN ESPECIALLY TRICKY ONE FOR CMX AND IWD...SO INCLUDED JUST A SCT DECK FOR NOW. ANY LO CLDS THAT DVLP TNGT SHOULD DISSIPATE ON WED AT CMX/IWD WITH DAYTIME HEATING...BUT THESE CLDS WL BE MORE RESILIENT AT SAW EVEN IF THE CIG HGT DOES LIFT ABV 1K FT INTO THE MVFR RANGE BY NOON. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 353 PM EDT TUE SEP 30 2014 HIGH PRESSURE OF OVER N ONTARIO WILL MOVE E TO THE CANADIAN MARITIMES BY WEDNESDAY EVENING. MEANWHILE...LOW PRESSURE OVER WESTERN NE WILL LIFT ACROSS S MANITOBA WEDNESDAY MORNING...AND TO HUDSON BAY THURSDAY MORNING. A TROUGH ASSOCIATED WITH THE LOW WILL MOVE E...REACHING LAKE SUPERIOR ON THURSDAY. A LOW WILL FORM ALONG THIS TROUGH OVER THE UPPER MS VALLEY THURSDAY EVENING AND THEN DEEPEN AS IT LIFTS INTO N ONTARIO FRIDAY...AND TO HUDSON BAY FRIDAY NIGHT. IN ITS WAKE...HIGH PRESSURE OVER THE W PLAINS FRIDAY AFTERNOON WILL SETTLE OVER THE LOWER MS VALLEY SATURDAY INTO SUNDAY...AS A TROUGH EXTENDING FROM THE HUDSON BAY LOW LINGERS OVER N ONTARIO. A PERIOD OF NEAR GALES OUT OF THE W-NW WILL BE POSSIBLE FROM LATE FRIDAY AFTERNOON THROUGH THE DAY SATURDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...TITUS AVIATION...KC MARINE...KF
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
312 PM EDT TUE SEP 30 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 311 PM EDT TUE SEP 30 2014 12Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW A SHARP UPR RDG EXTENDING FM THE MID MS RIVER VALLEY N INTO NW ONTARIO...SUPPORTING SFC HI PRES JUST N OF LK SUP. ALTHOUGH THE MID TROP IS QUITE DRY... WITH 12Z H5 DEWPT DEPRESSIONS AS HI AS 45C AT MPX AND QUAD CITIES... LINGERING LLVL MSTR TO THE S OF THE HI CENTER AND BLO SHARP SUBSIDENCE INVRN ARND H9-925 CAUSED QUITE A BIT OF LO CLD TO PERSIST OVER THE UPR LKS THRU THE MRNG. DAYTIME HEATING THAT HAS CAUSED THE LCL TO RISE THRU THE SLOWLY SINKING INVRN BASE PER FCST SDNGS IS RESULTING IN STEADY BREAKUP OF THE LO CLD EARLY THIS AFTN. THE LO CLDS HAVE BEEN MOST RESILIENT OVER THE CENTRAL...WHERE LLVL NE WIND IS UPSLOPING. LOOKING UPSTREAM...A VIGOROUS NEGATIVELY TILTED SHRTWV IS LIFTING NNEWD THRU THE NRN PLAINS. DESPITE THE MID LVL DRY AIR IN PLACE...SOME SHOWERS/TS IN THE RATHER NARROW WARM CONVEYOR BELT ASSOCIATED WITH THIS DISTURBANCE ARE MOVING INTO SW MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE FOCUSED ON CLD TRENDS. FCST CONCERNS ON WED SHIFT TO THE POTENTIAL FOR SOME SHOWERS IN THE INCRSG SLY FLOW/ISENTROPIC ASCENT TO THE E OF SHRTWV MOVING THRU THE NRN PLAINS INTO SCENTRAL CANADA. TNGT...ALTHOUGH THE LO CLDS WL CONTINUE TO DISSIPATE INTO THE EVNG WITH THE IMPACTS OF DAYTIME HEATING/MIXING...NOCTURNAL COOLING AND VEERING WINDS TO THE S THAT WL BRING A RETURN OF MOISTER H95-9 AIR SHOULD RESULT IN MORE LO CLDS. NOT OUT OF THE QUESTION THERE COULD BE SOME DRIZZLE OVER THE CENTRAL WHERE EXPECTED SSE WIND WL UPSLOPE OFF LK MI. THE ONE EXCEPTION WL BE OVER THE W...WHERE THE S WIND WL DOWNSLOPE AND PREVENT/LIMIT THE REFORMATION OF THE LO CLDS. OTRW... SOME MID/HI CLDS ON THE ERN FLANK OF THE WARM CONVEYOR BELT MSTR RIBBON MOVING E THRU WL INVADE THE W OVERNGT. THE COMBINATION OF LINGERING LO CLDS AND/OR INCRSG SLY FLOW WITH H925 WINDS INCRSG UP TO 20-30 KTS BY 12Z WED WL LIMIT THE DIURNAL TEMP FALL. BUT TEMPS SHOULD STILL FALL INTO THE 30S AT SOME OF THE INTERIOR COLD SPOTS THAT SEE MOCLR SKIES FOR A TIME. WED...ALTHOUGH THE PASSAGE OF SHRTWV/ACCOMPANYING DPVA AND DEEP LYR QVECTOR CNVGC WELL TO THE W THRU MANITOBA WL LIMIT THE PCPN POTENTIAL OVER UPR MI...RATHER NARROW WARM CONVEYOR BELT MSTR RIBBON AND AREA OF H85-5 QVECTOR CNVGC/UPR DVGC AND BAND OF H85-7 FGEN IN RRQ OF 80KT H3 JET MAX LIFTING NNEWD THRU NW ONTARIO WL BRING THE THREAT OF SHOWERS TO THE W IN THE AFTN. CONSIDERING THE STRONG DYNAMIC SUPPORT AND APPRECIABLE DEEP MOISTENING THAT IS FCST TO RAISE PWAT NEAR 1.5 INCHES /UP TO 200 PCT OF NORMAL/ BY 00Z THU...HI LIKELY POPS SEEM APPROPRIATE OVER THE FAR W. ALTHOUGH THE MID LVLS OVER THE E WL REMAIN DRY...FCST SDNGS INDICATE LO CLDS WL PERSIST MOST OF THE DAY IN THAT AREA AND LIMIT THE DAYTIME TEMP RECOVERY. BUT WITH STRENGTHENING SLY FLOW BRINGING A RETURN OF H85 TEMPS AS HI AS 12-13C...MAX TEMPS WL RISE ABV NORMAL...ESPECIALLY IN THE DOWNSLOPE AREAS NEAR LK SUP. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 433 AM EDT TUE SEP 30 2014 ATTENTION IN THE LONG TERM WILL BE ON THE UPPER TROUGH THAT WILL MOVE FROM THE INTERMOUNTAIN WEST AT 12Z WED INTO THE CWA AT 00Z SAT WHILE DEEPENING AND BECOMING NEGATIVELY TILTED...AS IS GENERALLY AGREED ON BY NWP. THE UPPER TROUGH THEN LOOKS TO CLOSE OFF INTO A LOW AS IT MOVES THROUGH THE REGION FRI NIGHT...BUT MODEL DISAGREEMENT INCREASES SIGNIFICANTLY AT THIS POINT WITH THE STRENGTH AND TRACK OF THE SYSTEM. GENERAL MODEL AGREEMENT DOES INCREASE SUN NIGHT INTO MON WITH MODELS SHOWING A DEEP TROUGH OVER THE ERN CONUS. ONE THING THAT CAN BE SAID WITH CERTAINTY IS THAT THE PATTERN WILL BE MORE ACTIVE THAN LAST WEEK. SHOWERS /POSSIBLY WITH SOME THUNDER/ IS STILL EXPECTED TO VERY GRADUALLY MOVE W TO E ACROSS THE CWA WED THROUGH THU DUE TO WAA/ISENTROPIC ASCENT AHEAD OF A SFC TROUGH/COLD FRONT. MAIN ISSUE TO POINT OUT FROM A CONFIDENCE STANDPOINT IS THAT SHORTWAVE ENERGY WILL PROBABLY EJECT FROM THE UPPER TROUGH TO THE W /AS SHOWN BY NWP/...BUT THE MODELS DO NO AGREE ON THE STRENGTH/TIMING/TRACK OF ANY ENERGY AND ASSOCIATED SFC CYCLOGENESIS. THERE WILL PROBABLY BE PERIODS OF HEAVIER PRECIP AND/OR GREATER PRECIP COVERAGE...BUT ACCURATELY TIMING THOSE OUT IS NOT POSSIBLE AT THIS TIME. HIGH TEMPS IN THE 60S LOOK TO MAKE A RETURN ON WED AND THU DUE TO THE WAA AND RESULTING WARM AIRMASS /850MB TEMPS OF 10-13C/. AS PREVIOUSLY MENTIONED...THE UPPER TROUGH TEARS INTO THE AREA THU NIGHT AND FRI...BRINGING A MUCH COLDER AIRMASS WITH IT. AT LEAST PORTIONS OF THE CWA SHOULD SEE 850MB TEMPS BELOW 0C BY THE END OF THE DAY FRI. GIVEN THE STRENGTH OF THE TROUGH AND MAGNITUDE OF RESULTING HEIGHT FALLS AS IT MOVES IN...PERIODS OF PRECIP DOES LOOK LIKE A GOOD BET THU NIGHT INTO FRI...ALTHOUGH AMOUNTS WILL BE DEPENDENT ON THE HIGHLY UNCERTAIN SFC LOW LEVEL FEATURES. SOME MODELS /MAINLY THE GFS AND NAM/ SHOW A DEEPER SFC LOW TRANSITING THE CWA THU NIGHT INTO FRI /AS THE GFS HAS SHOWN VARIOUS ITERATIONS OF FOR THE LAST SEVERAL RUNS/. IF THIS DOES OCCUR...GALES WOULD LIKELY OCCUR ACROSS PORTIONS OF THE GREAT LAKES...ALONG WITH MORE SUBSTANTIAL RAINFALL AMOUNTS. WHILE THIS IS NOT OUT OF THE QUESTION...THERE IS JUST TOO MUCH UNCERTAINTY AT THIS POINT TO ADD THIS SCENARIO TO THE FORECAST. PRECIP FRI NIGHT INTO SAT IS A BIT MORE CERTAIN SINCE IT WILL BE LESS DUE TO A SYNOPTIC SYSTEM AND MORE TO SUB ZERO 850MB TEMPS AND WNW-NW LOW LEVEL WINDS LEADING TO LAKE EFFECT PRECIP NEAR LAKE SUPERIOR. IN FACT...DEPENDING ON EXACTLY HOW COLD THE AIRMASS IS...SNOW IS CERTAINLY NOT OUT OF THE PICTURE FRI NIGHT INTO SAT NIGHT...BUT ACCUMULATING SNOW IS UNLIKELY /ESPECIALLY SIGNIFICANT ACCUMULATIONS/. DID ADD SNOW CHANCES TO THE FORECAST OVER HIGHER TERRAIN OF WRN UPPER MI FRI NIGHT INTO EARLY SAT AND FOR PORTIONS OF NWRN AND NERN UPPER MI SAT NIGHT. HIGH TEMPS BY SATURDAY LOOK TO BE IN THE UPPER 40S TO LOW 50S....WITH LOW TEMPS SAT NIGHT FROM THE UPPER 20S TO MID 30S. GOING COMPLETELY WITH MODEL CONSENSUS IDEA SUN AND MON GIVEN UNCERTAINTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 132 PM EDT TUE SEP 30 2014 DAYTIME HEATING/MIXING WL ALLOW LO CLDS AT SAW AND IWD TO BREAK UP THIS AFTN WITH A PERIOD OF VFR CONDITIONS INTO AT LEAST THIS EVNG. ALTHOUGH CMX MAY SEE SOME SC/LOWER CIGS EARLY THIS AFTN ON THE NRN FRINGE OF SLOWLY DISSIPATING MAIN LO CLD AREA TO THE S...EXPECT VFR CONDITIONS TO PREDOMINATE THERE INTO AT LEAST THIS EVNG. ONCE HI PRES IN ONTARIO SHIFTS FARTHER TO THE E TNGT AND A LO PRES TROF APRCHS FM THE W...THE LLVL WINDS WL SHIFT TO A MORE S DIRECTION. IN THE PRESENCE OF NOCTURNAL COOLING AND THE RETURN OF MOISTER LLVL AIR...EXPECT LO CLDS/IFR CONDITIONS TO DVLP AT SAW. DOWNSLOPE NATURE OF THIS LLVL FLOW MAKES THE FCST AN ESPECIALLY TRICKY ONE FOR CMX AND IWD...SO INCLUDED JUST A SCT DECK FOR NOW. ANY LO CLDS THAT DVLP TNGT SHOULD DISSIPATE ON WED AT CMX/IWD WITH DAYTIME HEATING...BUT THESE CLDS WL BE MORE RESILIENT AT SAW EVEN IF THE CIG HGT DOES LIFT ABV 1K FT INTO THE MVFR RANGE BY NOON. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 535 AM EDT TUE SEP 30 2014 WITH HIGH PRES JUST N OF LAKE SUPERIOR...WINDS WILL DIMINISH TO UNDER 20KT THIS MORNING. WINDS OVER FAR WRN LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT RANGE FOR A TIME THIS AFTN/EVENING AS THE HIGH BEGINS TO MOVE E. WINDS SHOULD OTHERWISE REMAIN UNDER 20KT THROUGH AT LEAST THU MORNING...THOUGH THERE MAY BE A SLIGHT UPTICK IN S TO SE WINDS OVER ERN LAKE SUPERIOR WED AS PRES GRADIENT TIGHTENS BTWN THE DEPARTING HIGH AND A COLD FRONT APPROACHING FROM THE W. THAT COLD FRONT WILL REACH LAKE SUPERIOR THU...AND THEN A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT OVER THE UPPER GREAT LAKES. DEPENDING ON WHERE THE LOW ORGANIZES AND HOW QUICKLY IT STRENGTHENS AS IT MOVES N THRU NRN ONTARIO...THERE WILL BE THE POTENTIAL FOR A PERIOD OF NW GALES OVER LAKE SUPERIOR AT SOME POINT FRI AND/OR SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...TITUS AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
133 PM EDT TUE SEP 30 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 535 AM EDT TUE SEP 30 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A POTENT SHORTWAVE LIFTING N THRU WRN NEBRASKA. IMMEDIATELY DOWNSTREAM IS A SHARP RIDGE EXTENDING FROM MO THRU MN INTO MANITOBA AND NRN ONTARIO. SHORTWAVE THAT PRODUCED SHOWERS HERE YESTERDAY IS NOW OVER LWR MI AND SRN ONTARIO. IN THE WAKE OF THAT SHORTWAVE...ABUNDANT LOW-LEVEL MOISTURE HAS BEEN TRAPPED UNDER A STRENGTHENING INVERSION...RESULTING IN OVC SKIES OVERNIGHT ACROSS UPPER MI WITH ONE EXCEPTION. DRIER AIR AND CLEAR SKIES HAVE ADVANCED S ACROSS CNTRL LAKE SUPERIOR TO THE TIP OF THE KEWEENAW PENINSULA. AT THE SFC...HIGH PRES WAS CENTERED OVER NRN ONTARIO. GIVEN THE STRENGTHENING INVERSION AND LOWER SUN ANGLE AT THIS TIME OF YEAR...IT WILL LIKELY TAKE A WHILE TO CLEAR OUT THE LOW CLOUDS ACROSS THE AREA TODAY. ALTHOUGH CLEARING HAS ADVANCED S TO THE TIP OF THE KEWEENAW OVERNIGHT...VEERING LOW-LEVEL WINDS TO AN EASTERLY DIRECTION RESULTING FROM THE SFC HIGH SHIFTING EASTWARD WILL SLOW AND STALL THE SOUTHWARD ADVANCE OF DRIER AIR. SATELLITE IMAGERY ALREADY SHOWS THIS OCCURRING. GIVEN WHERE THE CLEARING LINE IS UPSTREAM TO THE E OF LAKE SUPERIOR...HAVE SOME CONCERN THAT A GOOD PORTION OF THE AREA WILL NOT SEE MUCH CLEARING TODAY. FOR NOW...FCST WILL SHOW CLOUDS DOMINATING THIS MORNING AND THEN GRADUAL CLEARING IN THE AFTN. IT MAY END UP BEING THAT DOWNSLOPE AREAS WILL BE THE FIRST TO SEE INCREASING SUNSHINE THIS AFTN WITH CLEARING THEN SLOWLY EXPANDING FROM THERE. AS FOR TEMPS...LOWERED TEMPS A BIT FROM INHERITED FCST TO REFLECT THE MORE PESSIMISTIC CLEARING TREND. TEMPS MAY STRUGGLE TO REACH 50F OVER THE NCNTRL WHERE CLOUDS ARE LIKELY TO LINGER LONGEST. OTHERWISE...50S WIL BE THE RULE TODAY. IF SKIES DO CLEAR THIS AFTN/EVENING...CLOUDS WILL BE ON THE INCREASE AGAIN TONIGHT DUE TO CLOUDS SPREADING E FROM THE POTENT SHORTWAVE LIFTING THRU THE DAKOTAS BUT MORE SO DUE TO A RETURN OF LOWER CLOUDS LIFTING BACK INTO THE AREA FROM THE SE. ALTHOUGH POTENT SHORTWAVE WILL BE TAKING A TRACK WELL W OF HERE...RIBBON OF FAIRLY STRONG MOISTURE TRANSPORT INTO THE UPPER MISSISSIPPI VALLEY MAY SPREAD SCT SHRA AS FAR E AS FAR WRN LAKE SUPERIOR LATE TONIGHT. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 433 AM EDT TUE SEP 30 2014 ATTENTION IN THE LONG TERM WILL BE ON THE UPPER TROUGH THAT WILL MOVE FROM THE INTERMOUNTAIN WEST AT 12Z WED INTO THE CWA AT 00Z SAT WHILE DEEPENING AND BECOMING NEGATIVELY TILTED...AS IS GENERALLY AGREED ON BY NWP. THE UPPER TROUGH THEN LOOKS TO CLOSE OFF INTO A LOW AS IT MOVES THROUGH THE REGION FRI NIGHT...BUT MODEL DISAGREEMENT INCREASES SIGNIFICANTLY AT THIS POINT WITH THE STRENGTH AND TRACK OF THE SYSTEM. GENERAL MODEL AGREEMENT DOES INCREASE SUN NIGHT INTO MON WITH MODELS SHOWING A DEEP TROUGH OVER THE ERN CONUS. ONE THING THAT CAN BE SAID WITH CERTAINTY IS THAT THE PATTERN WILL BE MORE ACTIVE THAN LAST WEEK. SHOWERS /POSSIBLY WITH SOME THUNDER/ IS STILL EXPECTED TO VERY GRADUALLY MOVE W TO E ACROSS THE CWA WED THROUGH THU DUE TO WAA/ISENTROPIC ASCENT AHEAD OF A SFC TROUGH/COLD FRONT. MAIN ISSUE TO POINT OUT FROM A CONFIDENCE STANDPOINT IS THAT SHORTWAVE ENERGY WILL PROBABLY EJECT FROM THE UPPER TROUGH TO THE W /AS SHOWN BY NWP/...BUT THE MODELS DO NO AGREE ON THE STRENGTH/TIMING/TRACK OF ANY ENERGY AND ASSOCIATED SFC CYCLOGENESIS. THERE WILL PROBABLY BE PERIODS OF HEAVIER PRECIP AND/OR GREATER PRECIP COVERAGE...BUT ACCURATELY TIMING THOSE OUT IS NOT POSSIBLE AT THIS TIME. HIGH TEMPS IN THE 60S LOOK TO MAKE A RETURN ON WED AND THU DUE TO THE WAA AND RESULTING WARM AIRMASS /850MB TEMPS OF 10-13C/. AS PREVIOUSLY MENTIONED...THE UPPER TROUGH TEARS INTO THE AREA THU NIGHT AND FRI...BRINGING A MUCH COLDER AIRMASS WITH IT. AT LEAST PORTIONS OF THE CWA SHOULD SEE 850MB TEMPS BELOW 0C BY THE END OF THE DAY FRI. GIVEN THE STRENGTH OF THE TROUGH AND MAGNITUDE OF RESULTING HEIGHT FALLS AS IT MOVES IN...PERIODS OF PRECIP DOES LOOK LIKE A GOOD BET THU NIGHT INTO FRI...ALTHOUGH AMOUNTS WILL BE DEPENDENT ON THE HIGHLY UNCERTAIN SFC LOW LEVEL FEATURES. SOME MODELS /MAINLY THE GFS AND NAM/ SHOW A DEEPER SFC LOW TRANSITING THE CWA THU NIGHT INTO FRI /AS THE GFS HAS SHOWN VARIOUS ITERATIONS OF FOR THE LAST SEVERAL RUNS/. IF THIS DOES OCCUR...GALES WOULD LIKELY OCCUR ACROSS PORTIONS OF THE GREAT LAKES...ALONG WITH MORE SUBSTANTIAL RAINFALL AMOUNTS. WHILE THIS IS NOT OUT OF THE QUESTION...THERE IS JUST TOO MUCH UNCERTAINTY AT THIS POINT TO ADD THIS SCENARIO TO THE FORECAST. PRECIP FRI NIGHT INTO SAT IS A BIT MORE CERTAIN SINCE IT WILL BE LESS DUE TO A SYNOPTIC SYSTEM AND MORE TO SUB ZERO 850MB TEMPS AND WNW-NW LOW LEVEL WINDS LEADING TO LAKE EFFECT PRECIP NEAR LAKE SUPERIOR. IN FACT...DEPENDING ON EXACTLY HOW COLD THE AIRMASS IS...SNOW IS CERTAINLY NOT OUT OF THE PICTURE FRI NIGHT INTO SAT NIGHT...BUT ACCUMULATING SNOW IS UNLIKELY /ESPECIALLY SIGNIFICANT ACCUMULATIONS/. DID ADD SNOW CHANCES TO THE FORECAST OVER HIGHER TERRAIN OF WRN UPPER MI FRI NIGHT INTO EARLY SAT AND FOR PORTIONS OF NWRN AND NERN UPPER MI SAT NIGHT. HIGH TEMPS BY SATURDAY LOOK TO BE IN THE UPPER 40S TO LOW 50S....WITH LOW TEMPS SAT NIGHT FROM THE UPPER 20S TO MID 30S. GOING COMPLETELY WITH MODEL CONSENSUS IDEA SUN AND MON GIVEN UNCERTAINTY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 132 PM EDT TUE SEP 30 2014 DAYTIME HEATING/MIXING WL ALLOW LO CLDS AT SAW AND IWD TO BREAK UP THIS AFTN WITH A PERIOD OF VFR CONDITIONS INTO AT LEAST THIS EVNG. ALTHOUGH CMX MAY SEE SOME SC/LOWER CIGS EARLY THIS AFTN ON THE NRN FRINGE OF SLOWLY DISSIPATING MAIN LO CLD AREA TO THE S...EXPECT VFR CONDITIONS TO PREDOMINATE THERE INTO AT LEAST THIS EVNG. ONCE HI PRES IN ONTARIO SHIFTS FARTHER TO THE E TNGT AND A LO PRES TROF APRCHS FM THE W...THE LLVL WINDS WL SHIFT TO A MORE S DIRECTION. IN THE PRESENCE OF NOCTURNAL COOLING AND THE RETURN OF MOISTER LLVL AIR...EXPECT LO CLDS/IFR CONDITIONS TO DVLP AT SAW. DOWNSLOPE NATURE OF THIS LLVL FLOW MAKES THE FCST AN ESPECIALLY TRICKY ONE FOR CMX AND IWD...SO INCLUDED JUST A SCT DECK FOR NOW. ANY LO CLDS THAT DVLP TNGT SHOULD DISSIPATE ON WED AT CMX/IWD WITH DAYTIME HEATING...BUT THESE CLDS WL BE MORE RESILIENT AT SAW EVEN IF THE CIG HGT DOES LIFT ABV 1K FT INTO THE MVFR RANGE BY NOON. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 535 AM EDT TUE SEP 30 2014 WITH HIGH PRES JUST N OF LAKE SUPERIOR...WINDS WILL DIMINISH TO UNDER 20KT THIS MORNING. WINDS OVER FAR WRN LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT RANGE FOR A TIME THIS AFTN/EVENING AS THE HIGH BEGINS TO MOVE E. WINDS SHOULD OTHERWISE REMAIN UNDER 20KT THROUGH AT LEAST THU MORNING...THOUGH THERE MAY BE A SLIGHT UPTICK IN S TO SE WINDS OVER ERN LAKE SUPERIOR WED AS PRES GRADIENT TIGHTENS BTWN THE DEPARTING HIGH AND A COLD FRONT APPROACHING FROM THE W. THAT COLD FRONT WILL REACH LAKE SUPERIOR THU...AND THEN A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT OVER THE UPPER GREAT LAKES. DEPENDING ON WHERE THE LOW ORGANIZES AND HOW QUICKLY IT STRENGTHENS AS IT MOVES N THRU NRN ONTARIO...THERE WILL BE THE POTENTIAL FOR A PERIOD OF NW GALES OVER LAKE SUPERIOR AT SOME POINT FRI AND/OR SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...KC MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
739 AM EDT TUE SEP 30 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 535 AM EDT TUE SEP 30 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A POTENT SHORTWAVE LIFTING N THRU WRN NEBRASKA. IMMEDIATELY DOWNSTREAM IS A SHARP RIDGE EXTENDING FROM MO THRU MN INTO MANITOBA AND NRN ONTARIO. SHORTWAVE THAT PRODUCED SHOWERS HERE YESTERDAY IS NOW OVER LWR MI AND SRN ONTARIO. IN THE WAKE OF THAT SHORTWAVE...ABUNDANT LOW-LEVEL MOISTURE HAS BEEN TRAPPED UNDER A STRENGTHENING INVERSION...RESULTING IN OVC SKIES OVERNIGHT ACROSS UPPER MI WITH ONE EXCEPTION. DRIER AIR AND CLEAR SKIES HAVE ADVANCED S ACROSS CNTRL LAKE SUPERIOR TO THE TIP OF THE KEWEENAW PENINSULA. AT THE SFC...HIGH PRES WAS CENTERED OVER NRN ONTARIO. GIVEN THE STRENGTHENING INVERSION AND LOWER SUN ANGLE AT THIS TIME OF YEAR...IT WILL LIKELY TAKE A WHILE TO CLEAR OUT THE LOW CLOUDS ACROSS THE AREA TODAY. ALTHOUGH CLEARING HAS ADVANCED S TO THE TIP OF THE KEWEENAW OVERNIGHT...VEERING LOW-LEVEL WINDS TO AN EASTERLY DIRECTION RESULTING FROM THE SFC HIGH SHIFTING EASTWARD WILL SLOW AND STALL THE SOUTHWARD ADVANCE OF DRIER AIR. SATELLITE IMAGERY ALREADY SHOWS THIS OCCURRING. GIVEN WHERE THE CLEARING LINE IS UPSTREAM TO THE E OF LAKE SUPERIOR...HAVE SOME CONCERN THAT A GOOD PORTION OF THE AREA WILL NOT SEE MUCH CLEARING TODAY. FOR NOW...FCST WILL SHOW CLOUDS DOMINATING THIS MORNING AND THEN GRADUAL CLEARING IN THE AFTN. IT MAY END UP BEING THAT DOWNSLOPE AREAS WILL BE THE FIRST TO SEE INCREASING SUNSHINE THIS AFTN WITH CLEARING THEN SLOWLY EXPANDING FROM THERE. AS FOR TEMPS...LOWERED TEMPS A BIT FROM INHERITED FCST TO REFLECT THE MORE PESSIMISTIC CLEARING TREND. TEMPS MAY STRUGGLE TO REACH 50F OVER THE NCNTRL WHERE CLOUDS ARE LIKELY TO LINGER LONGEST. OTHERWISE...50S WIL BE THE RULE TODAY. IF SKIES DO CLEAR THIS AFTN/EVENING...CLOUDS WILL BE ON THE INCREASE AGAIN TONIGHT DUE TO CLOUDS SPREADING E FROM THE POTENT SHORTWAVE LIFTING THRU THE DAKOTAS BUT MORE SO DUE TO A RETURN OF LOWER CLOUDS LIFTING BACK INTO THE AREA FROM THE SE. ALTHOUGH POTENT SHORTWAVE WILL BE TAKING A TRACK WELL W OF HERE...RIBBON OF FAIRLY STRONG MOISTURE TRANSPORT INTO THE UPPER MISSISSIPPI VALLEY MAY SPREAD SCT SHRA AS FAR E AS FAR WRN LAKE SUPERIOR LATE TONIGHT. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 433 AM EDT TUE SEP 30 2014 ATTENTION IN THE LONG TERM WILL BE ON THE UPPER TROUGH THAT WILL MOVE FROM THE INTERMOUNTAIN WEST AT 12Z WED INTO THE CWA AT 00Z SAT WHILE DEEPENING AND BECOMING NEGATIVELY TILTED...AS IS GENERALLY AGREED ON BY NWP. THE UPPER TROUGH THEN LOOKS TO CLOSE OFF INTO A LOW AS IT MOVES THROUGH THE REGION FRI NIGHT...BUT MODEL DISAGREEMENT INCREASES SIGNIFICANTLY AT THIS POINT WITH THE STRENGTH AND TRACK OF THE SYSTEM. GENERAL MODEL AGREEMENT DOES INCREASE SUN NIGHT INTO MON WITH MODELS SHOWING A DEEP TROUGH OVER THE ERN CONUS. ONE THING THAT CAN BE SAID WITH CERTAINTY IS THAT THE PATTERN WILL BE MORE ACTIVE THAN LAST WEEK. SHOWERS /POSSIBLY WITH SOME THUNDER/ IS STILL EXPECTED TO VERY GRADUALLY MOVE W TO E ACROSS THE CWA WED THROUGH THU DUE TO WAA/ISENTROPIC ASCENT AHEAD OF A SFC TROUGH/COLD FRONT. MAIN ISSUE TO POINT OUT FROM A CONFIDENCE STANDPOINT IS THAT SHORTWAVE ENERGY WILL PROBABLY EJECT FROM THE UPPER TROUGH TO THE W /AS SHOWN BY NWP/...BUT THE MODELS DO NO AGREE ON THE STRENGTH/TIMING/TRACK OF ANY ENERGY AND ASSOCIATED SFC CYCLOGENESIS. THERE WILL PROBABLY BE PERIODS OF HEAVIER PRECIP AND/OR GREATER PRECIP COVERAGE...BUT ACCURATELY TIMING THOSE OUT IS NOT POSSIBLE AT THIS TIME. HIGH TEMPS IN THE 60S LOOK TO MAKE A RETURN ON WED AND THU DUE TO THE WAA AND RESULTING WARM AIRMASS /850MB TEMPS OF 10-13C/. AS PREVIOUSLY MENTIONED...THE UPPER TROUGH TEARS INTO THE AREA THU NIGHT AND FRI...BRINGING A MUCH COLDER AIRMASS WITH IT. AT LEAST PORTIONS OF THE CWA SHOULD SEE 850MB TEMPS BELOW 0C BY THE END OF THE DAY FRI. GIVEN THE STRENGTH OF THE TROUGH AND MAGNITUDE OF RESULTING HEIGHT FALLS AS IT MOVES IN...PERIODS OF PRECIP DOES LOOK LIKE A GOOD BET THU NIGHT INTO FRI...ALTHOUGH AMOUNTS WILL BE DEPENDENT ON THE HIGHLY UNCERTAIN SFC LOW LEVEL FEATURES. SOME MODELS /MAINLY THE GFS AND NAM/ SHOW A DEEPER SFC LOW TRANSITING THE CWA THU NIGHT INTO FRI /AS THE GFS HAS SHOWN VARIOUS ITERATIONS OF FOR THE LAST SEVERAL RUNS/. IF THIS DOES OCCUR...GALES WOULD LIKELY OCCUR ACROSS PORTIONS OF THE GREAT LAKES...ALONG WITH MORE SUBSTANTIAL RAINFALL AMOUNTS. WHILE THIS IS NOT OUT OF THE QUESTION...THERE IS JUST TOO MUCH UNCERTAINTY AT THIS POINT TO ADD THIS SCENARIO TO THE FORECAST. PRECIP FRI NIGHT INTO SAT IS A BIT MORE CERTAIN SINCE IT WILL BE LESS DUE TO A SYNOPTIC SYSTEM AND MORE TO SUB ZERO 850MB TEMPS AND WNW-NW LOW LEVEL WINDS LEADING TO LAKE EFFECT PRECIP NEAR LAKE SUPERIOR. IN FACT...DEPENDING ON EXACTLY HOW COLD THE AIRMASS IS...SNOW IS CERTAINLY NOT OUT OF THE PICTURE FRI NIGHT INTO SAT NIGHT...BUT ACCUMULATING SNOW IS UNLIKELY /ESPECIALLY SIGNIFICANT ACCUMULATIONS/. DID ADD SNOW CHANCES TO THE FORECAST OVER HIGHER TERRAIN OF WRN UPPER MI FRI NIGHT INTO EARLY SAT AND FOR PORTIONS OF NWRN AND NERN UPPER MI SAT NIGHT. HIGH TEMPS BY SATURDAY LOOK TO BE IN THE UPPER 40S TO LOW 50S....WITH LOW TEMPS SAT NIGHT FROM THE UPPER 20S TO MID 30S. GOING COMPLETELY WITH MODEL CONSENSUS IDEA SUN AND MON GIVEN UNCERTAINTY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z WEDNESDAY MORNING) ISSUED AT 737 AM EDT TUE SEP 30 2014 CONSIDERABLE LOW-LEVEL MOISTURE CONTINUES TO LINGER OVER UPPER MI EARLY THIS MORNING UNDER STRENGTHENING INVERSION...RESULTING IN MVFR TO IFR CIGS. THE CLEARING LINE HAS ADVANCED AS FAR S AS NEAR KCMX...BUT HAS NEARLY STALLED NOW. BASED ON SATELLITE IMAGERY AND EXPECTED SLOWLY VEERING WINDS TODAY...KCMX SHOULD SEE MVFR CIGS SCATTER OUT TO PREVAILING VFR BY AFTN. LOCATED FARTHER INTO THE LOW CLOUDS... KIWD WILL SEE IFR TO LOW MVFR CIGS PERSIST THRU THE MORNING. DEVELOPING LIGHT DOWNSLOPE WIND SHOULD RESULT IN CLOUDS SCATTERING OUT TO PREVAILING VFR DURING THE MID AFTN HRS. AT KSAW...UPSLOPE WIND THROUGH THE DAY WILL PROBABLY RESULT IN MVFR CIGS LINGERING UNTIL LATE AFTN. VFR CONDITIONS WILL THEN BE THE RULE AT KIWD/KCMX TONIGHT. AT KSAW...EXPECT VFR CONDITIONS THIS EVENING...THEN AS WINDS VEER TO THE SE...LOW-LEVEL MOISTURE/CLOUDS THAT WILL STILL BE LINGERING TO THE SE OF THE AREA WILL ADVECT BACK TO THE NW...BRINGING LOW MVFR CIGS TO KSAW OVERNIGHT. UNDER S TO SE UPSLOPE FLOW...CIGS WILL LIKELY FALL FARTHER TO IFR AND POTENTIALLY LIFR LATE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 535 AM EDT TUE SEP 30 2014 WITH HIGH PRES JUST N OF LAKE SUPERIOR...WINDS WILL DIMINISH TO UNDER 20KT THIS MORNING. WINDS OVER FAR WRN LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT RANGE FOR A TIME THIS AFTN/EVENING AS THE HIGH BEGINS TO MOVE E. WINDS SHOULD OTHERWISE REMAIN UNDER 20KT THROUGH AT LEAST THU MORNING...THOUGH THERE MAY BE A SLIGHT UPTICK IN S TO SE WINDS OVER ERN LAKE SUPERIOR WED AS PRES GRADIENT TIGHTENS BTWN THE DEPARTING HIGH AND A COLD FRONT APPROACHING FROM THE W. THAT COLD FRONT WILL REACH LAKE SUPERIOR THU...AND THEN A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT OVER THE UPPER GREAT LAKES. DEPENDING ON WHERE THE LOW ORGANIZES AND HOW QUICKLY IT STRENGTHENS AS IT MOVES N THRU NRN ONTARIO...THERE WILL BE THE POTENTIAL FOR A PERIOD OF NW GALES OVER LAKE SUPERIOR AT SOME POINT FRI AND/OR SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
535 AM EDT TUE SEP 30 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 535 AM EDT TUE SEP 30 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW A POTENT SHORTWAVE LIFTING N THRU WRN NEBRASKA. IMMEDIATELY DOWNSTREAM IS A SHARP RIDGE EXTENDING FROM MO THRU MN INTO MANITOBA AND NRN ONTARIO. SHORTWAVE THAT PRODUCED SHOWERS HERE YESTERDAY IS NOW OVER LWR MI AND SRN ONTARIO. IN THE WAKE OF THAT SHORTWAVE...ABUNDANT LOW-LEVEL MOISTURE HAS BEEN TRAPPED UNDER A STRENGTHENING INVERSION...RESULTING IN OVC SKIES OVERNIGHT ACROSS UPPER MI WITH ONE EXCEPTION. DRIER AIR AND CLEAR SKIES HAVE ADVANCED S ACROSS CNTRL LAKE SUPERIOR TO THE TIP OF THE KEWEENAW PENINSULA. AT THE SFC...HIGH PRES WAS CENTERED OVER NRN ONTARIO. GIVEN THE STRENGTHENING INVERSION AND LOWER SUN ANGLE AT THIS TIME OF YEAR...IT WILL LIKELY TAKE A WHILE TO CLEAR OUT THE LOW CLOUDS ACROSS THE AREA TODAY. ALTHOUGH CLEARING HAS ADVANCED S TO THE TIP OF THE KEWEENAW OVERNIGHT...VEERING LOW-LEVEL WINDS TO AN EASTERLY DIRECTION RESULTING FROM THE SFC HIGH SHIFTING EASTWARD WILL SLOW AND STALL THE SOUTHWARD ADVANCE OF DRIER AIR. SATELLITE IMAGERY ALREADY SHOWS THIS OCCURRING. GIVEN WHERE THE CLEARING LINE IS UPSTREAM TO THE E OF LAKE SUPERIOR...HAVE SOME CONCERN THAT A GOOD PORTION OF THE AREA WILL NOT SEE MUCH CLEARING TODAY. FOR NOW...FCST WILL SHOW CLOUDS DOMINATING THIS MORNING AND THEN GRADUAL CLEARING IN THE AFTN. IT MAY END UP BEING THAT DOWNSLOPE AREAS WILL BE THE FIRST TO SEE INCREASING SUNSHINE THIS AFTN WITH CLEARING THEN SLOWLY EXPANDING FROM THERE. AS FOR TEMPS...LOWERED TEMPS A BIT FROM INHERITED FCST TO REFLECT THE MORE PESSIMISTIC CLEARING TREND. TEMPS MAY STRUGGLE TO REACH 50F OVER THE NCNTRL WHERE CLOUDS ARE LIKELY TO LINGER LONGEST. OTHERWISE...50S WIL BE THE RULE TODAY. IF SKIES DO CLEAR THIS AFTN/EVENING...CLOUDS WILL BE ON THE INCREASE AGAIN TONIGHT DUE TO CLOUDS SPREADING E FROM THE POTENT SHORTWAVE LIFTING THRU THE DAKOTAS BUT MORE SO DUE TO A RETURN OF LOWER CLOUDS LIFTING BACK INTO THE AREA FROM THE SE. ALTHOUGH POTENT SHORTWAVE WILL BE TAKING A TRACK WELL W OF HERE...RIBBON OF FAIRLY STRONG MOISTURE TRANSPORT INTO THE UPPER MISSISSIPPI VALLEY MAY SPREAD SCT SHRA AS FAR E AS FAR WRN LAKE SUPERIOR LATE TONIGHT. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 433 AM EDT TUE SEP 30 2014 ATTENTION IN THE LONG TERM WILL BE ON THE UPPER TROUGH THAT WILL MOVE FROM THE INTERMOUNTAIN WEST AT 12Z WED INTO THE CWA AT 00Z SAT WHILE DEEPENING AND BECOMING NEGATIVELY TILTED...AS IS GENERALLY AGREED ON BY NWP. THE UPPER TROUGH THEN LOOKS TO CLOSE OFF INTO A LOW AS IT MOVES THROUGH THE REGION FRI NIGHT...BUT MODEL DISAGREEMENT INCREASES SIGNIFICANTLY AT THIS POINT WITH THE STRENGTH AND TRACK OF THE SYSTEM. GENERAL MODEL AGREEMENT DOES INCREASE SUN NIGHT INTO MON WITH MODELS SHOWING A DEEP TROUGH OVER THE ERN CONUS. ONE THING THAT CAN BE SAID WITH CERTAINTY IS THAT THE PATTERN WILL BE MORE ACTIVE THAN LAST WEEK. SHOWERS /POSSIBLY WITH SOME THUNDER/ IS STILL EXPECTED TO VERY GRADUALLY MOVE W TO E ACROSS THE CWA WED THROUGH THU DUE TO WAA/ISENTROPIC ASCENT AHEAD OF A SFC TROUGH/COLD FRONT. MAIN ISSUE TO POINT OUT FROM A CONFIDENCE STANDPOINT IS THAT SHORTWAVE ENERGY WILL PROBABLY EJECT FROM THE UPPER TROUGH TO THE W /AS SHOWN BY NWP/...BUT THE MODELS DO NO AGREE ON THE STRENGTH/TIMING/TRACK OF ANY ENERGY AND ASSOCIATED SFC CYCLOGENESIS. THERE WILL PROBABLY BE PERIODS OF HEAVIER PRECIP AND/OR GREATER PRECIP COVERAGE...BUT ACCURATELY TIMING THOSE OUT IS NOT POSSIBLE AT THIS TIME. HIGH TEMPS IN THE 60S LOOK TO MAKE A RETURN ON WED AND THU DUE TO THE WAA AND RESULTING WARM AIRMASS /850MB TEMPS OF 10-13C/. AS PREVIOUSLY MENTIONED...THE UPPER TROUGH TEARS INTO THE AREA THU NIGHT AND FRI...BRINGING A MUCH COLDER AIRMASS WITH IT. AT LEAST PORTIONS OF THE CWA SHOULD SEE 850MB TEMPS BELOW 0C BY THE END OF THE DAY FRI. GIVEN THE STRENGTH OF THE TROUGH AND MAGNITUDE OF RESULTING HEIGHT FALLS AS IT MOVES IN...PERIODS OF PRECIP DOES LOOK LIKE A GOOD BET THU NIGHT INTO FRI...ALTHOUGH AMOUNTS WILL BE DEPENDENT ON THE HIGHLY UNCERTAIN SFC LOW LEVEL FEATURES. SOME MODELS /MAINLY THE GFS AND NAM/ SHOW A DEEPER SFC LOW TRANSITING THE CWA THU NIGHT INTO FRI /AS THE GFS HAS SHOWN VARIOUS ITERATIONS OF FOR THE LAST SEVERAL RUNS/. IF THIS DOES OCCUR...GALES WOULD LIKELY OCCUR ACROSS PORTIONS OF THE GREAT LAKES...ALONG WITH MORE SUBSTANTIAL RAINFALL AMOUNTS. WHILE THIS IS NOT OUT OF THE QUESTION...THERE IS JUST TOO MUCH UNCERTAINTY AT THIS POINT TO ADD THIS SCENARIO TO THE FORECAST. PRECIP FRI NIGHT INTO SAT IS A BIT MORE CERTAIN SINCE IT WILL BE LESS DUE TO A SYNOPTIC SYSTEM AND MORE TO SUB ZERO 850MB TEMPS AND WNW-NW LOW LEVEL WINDS LEADING TO LAKE EFFECT PRECIP NEAR LAKE SUPERIOR. IN FACT...DEPENDING ON EXACTLY HOW COLD THE AIRMASS IS...SNOW IS CERTAINLY NOT OUT OF THE PICTURE FRI NIGHT INTO SAT NIGHT...BUT ACCUMULATING SNOW IS UNLIKELY /ESPECIALLY SIGNIFICANT ACCUMULATIONS/. DID ADD SNOW CHANCES TO THE FORECAST OVER HIGHER TERRAIN OF WRN UPPER MI FRI NIGHT INTO EARLY SAT AND FOR PORTIONS OF NWRN AND NERN UPPER MI SAT NIGHT. HIGH TEMPS BY SATURDAY LOOK TO BE IN THE UPPER 40S TO LOW 50S....WITH LOW TEMPS SAT NIGHT FROM THE UPPER 20S TO MID 30S. GOING COMPLETELY WITH MODEL CONSENSUS IDEA SUN AND MON GIVEN UNCERTAINTY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 133 AM EDT TUE SEP 30 2014 CONSIDERABLE LOW-LEVEL MOISTURE WILL LINGER OVERNIGHT WITH CIGS NEAR IFR/MVFR THRESHOLD AT KIWD/KCMX/KSAW. HOWEVER...SOME DRYING WILL PUSH INTO UPPER MI...AND THIS SHOULD RESULT IN CIGS CLIMBING TO AT OR ABOVE 2K FT THIS MORNING. DAYTIME MIXING AND ADDITIONAL DRY ADVECTION WILL RESULT IN ENOUGH CLEARING FOR VFR CONDITIONS AT KCMX BY LATE MORNING...AT IWD BY AFTN AND AT KSAW BY LATE AFTN WHERE MORE PERSISTENT UPSLOPE FLOW PREVAILS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 535 AM EDT TUE SEP 30 2014 WITH HIGH PRES JUST N OF LAKE SUPERIOR...WINDS WILL DIMINISH TO UNDER 20KT THIS MORNING. WINDS OVER FAR WRN LAKE SUPERIOR MAY INCREASE INTO THE 15-25KT RANGE FOR A TIME THIS AFTN/EVENING AS THE HIGH BEGINS TO MOVE E. WINDS SHOULD OTHERWISE REMAIN UNDER 20KT THROUGH AT LEAST THU MORNING...THOUGH THERE MAY BE A SLIGHT UPTICK IN S TO SE WINDS OVER ERN LAKE SUPERIOR WED AS PRES GRADIENT TIGHTENS BTWN THE DEPARTING HIGH AND A COLD FRONT APPROACHING FROM THE W. THAT COLD FRONT WILL REACH LAKE SUPERIOR THU...AND THEN A WAVE OF LOW PRES WILL DEVELOP ALONG THE FRONT OVER THE UPPER GREAT LAKES. DEPENDING ON WHERE THE LOW ORGANIZES AND HOW QUICKLY IT STRENGTHENS AS IT MOVES N THRU NRN ONTARIO...THERE WILL BE THE POTENTIAL FOR A PERIOD OF NW GALES OVER LAKE SUPERIOR AT SOME POINT FRI AND/OR SAT. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...TITUS AVIATION...JLB MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
909 PM CDT Wed Oct 1 2014 .UPDATE: Issued at 853 PM CDT Wed Oct 1 2014 Forecast looks to be generally on track and I don`t foresee any major changes for the rest of the evening. Instability is waning, but obviously there`s enough to keep some rather strong storms going. Will most likely let WW511 expire naturally at 1000 PM. The challenge after 1000 PM will be trying to figure out exactly where the heaviest rain will fall for the rest of the night. It still looks like the best threat for heavy rain and training will be over parts of our central Missouri counties. RAP is persistently showing moderate to strong moisture convergence at 850mb. Storms this evening have been efficient rain producers, and I expect this will not change. No change to flash flood watch at this time, and will probably only tweak PoPs to match current radar trends. Carney && .SHORT TERM: (Through Thursday Night) Issued at 340 PM CDT Wed Oct 1 2014 Lots to keep track of in the next 24 to 36 hours. First: severe thunderstorms have developed along the outflow boundary in central Missouri left over from storms earlier today. Modest instability between 1000-1500 J/Kg combined with around 40 kts bulk shear have produced a supercell which is riding the boundary. A few more cells are developing ahead of the big storm and may continue to strengthen. Expect the severe threat to continue into the early to mid evening hours...generally along and south of I-70. Should see storms weaken within a few hours of sunset, but then the low level jet strengthens in southwest flow ahead of the broad trof over the Rockies and developing low level circulation over the Plains. This will bring the second area of concern into play: heavy rain. Thunderstorms this morning and now this current round of severe convection will saturate the ground and increase the potential for flash flooding. Aforementioned 30-40kt low level jet is bringing plenty of Gulf moisture up into the area. Forecast soundings show a warm cloud depth of nearly 12,000 FT and BUFKIT is indicating that individual convective elements may move very slowly and train over the same locations. Current QPF from WPC shows rainfall in excess of 3 inches over the next 24 hours with locally higher amounts in addition to what`s already fallen. Therefore have gone ahead and pushed a flash flood watch for parts of central, northeast, and east central Missouri. Watch may need to be extended further east or northeast tonight as the situation develops. Attention turns to tomorrow when the upper level trof moves into the Great Plains and the associated surface system moves from northern Oklahoma into eastern Iowa through the day. Our CWFA will be squarely in the warm sector through the day, and even if there are no breaks in the clouds temperatures should be at least between 80 and 85...if not a tad bit warmer. With warm, humid airmass in place, NAM is forecasting SBCAPE values in excess of 2500 J/Kg in some parts of the CWFA. With 30-40kts of deep layer shear, and the approaching shortwave becoming negatively tilted , this looks like a good setup for severe weather during the afternoon and evening hours. The shear vector looks like it will be parallel to the front so the most likely convective mode will be a squall line with bows and LEWPS possible. The front will sweep through the area overnight Thursday night and we should be into cold advection by 12Z Friday morning. Carney .LONG TERM: (Thursday through Next Wednesday) Issued at 403 PM CDT Wed Oct 1 2014 Fall returns with a vengeance Friday and Saturday. Temperatures will drop 25 to 30 degrees behind the front Friday and Saturday. It will also be pretty breezy behind the front on Friday. Forecast soundings show some pretty good mixing which is likely to produce wind gusts in excess of 30 mph. Guidance is hinting at lows in the 30s across most of the area on Saturday morning, and this looks reasonable given the strength of the cold advection. This could easily be the coolest night of the season so far. Temperatures slowly moderate Sunday through next Wednesday. The highly amplified upper level pattern featuring a strong vortex just north of the Great Lakes region and a longwave trof over the eastern 1/2 of the CONUS will slowly become more zonal through midweek. By Wednesday the flow aloft should be nearly zonal and low level warm advection will bring temperatures back to near or above normal. Carney && .AVIATION: (For the 00z TAFs through 00z Thursday Evening) Issued at 650 PM CDT Wed Oct 1 2014 Primary concern for tonight is thunderstorms. Best chances for storms look like it will be from central Missouri, north of I-44 into the STL Metro area and then along and north of I-70 tonight. IFR visibilities in heavy rain will accompany these storms at times. Think flight conditions should be mainly VFR outside of thunderstorms. Numerous thunderstorms are expected across the area on Thursday as well. Expect VFR conditions and southwest flow to prevail outside of storms. Specifics for KSTL: Occasional thunderstorms will affect the terminal tonight. IFR visibilities in heavy rain will accompany these storms. Expect VFR flight conditions to prevail outside of storms. Numerous thunderstorms are expected on Thursday. Timing is uncertain, however the best chance for storms will likely be during the afternoon and evening hours. Carney && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FLASH FLOOD WATCH through Thursday evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Gasconade MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
317 PM CDT TUE SEP 30 2014 .SHORT TERM...(TONIGHT THROUGH FRIDAY) ISSUED AT 315 PM CDT TUE SEP 30 2014 GIVEN LATEST TRENDS OF SD SFC LOW...SVR THREAT OVER THE NRN CWA FOR THIS AFTN/EVENING LOOKING LESS LIKELY THAT PREVIOUSLY THOUGHT. AT PRESENT SFC LOW WAS CENTERED OVER WRN SD WITH MOISTURE FEED RUNNING UP THE MO VLY REGION INTO THE SYSTEM. THE RAP HAS BEEN CONSISTENT THE LAST SEVERAL RUNS TAKING THE POTENT UPPER LVL VORT MAX/SFC REFLECTION TRIPLE POINT IN A MORE NORTHERLY TRACK. HOWEVER...CANNOT TOTALLY DISCOUNT SOME TSTM ACTIVITY DEVELOPING LATER ON...THUS WILL HAVE TO AT LEAST MAINTAIN SMALL POPS DURING THE OVERNIGHT HOURS. MOVING ON...NEXT SEVERAL DAYS PCPN CHANCES WILL REVOLVE AROUND NEXT COLD FRONT DROPPING INTO THE CNTRL PLAINS. BOTH NAM/GFS IN GENERAL AGREEMENT SFC BNDRY WILL STRETCH FROM THE UPPER MIDWEST ERN CO...AND SHOULD BE STAGNANT THRU THE DAY DUE TO PARALLEL FLOW ALOFT. BY WED NIGHT THOUGH...A SHORTWAVE TROF EXITING THE CNTRL ROCKIES WILL ACT TO HELP DISPLACE THE SFC FRONT EWD...AND IS PROGGED TO EXTEND FROM THE WRN GREAT LAKES REGION TO ERN OK BY THUR AFTN. AT THIS POINT FEEL THE ARW/NMM BEST REFLECTS ANTICIPATED PROGRESSION OF PCPN ACTIVITY DURING THIS TIME...THUS HAVE GEARED POPS ACCORDINGLY. AS FOR SVR POTENTIAL WED AFTN...STOUT INSTABILITY WILL BE ON HAND. HOWEVER...BOTH NAM/GFS SEEM TO FAVOR SVR TSTM DEVELOPMENT MAINLY SOUTH OF THE CWA WHERE EFFECTIVE SHEAR WILL BE MOST PREVALENT. NEVERTHELESS...THERE IS STILL AT LEAST A SMALL CHANCE AREAS SOUTH OF I-80 COULD SEE STRONG/NEAR SVR STORMS. IN REGARDS TO RAINFALL...GIVEN SLOW NATURE OF PASSING BNDRY COUPLED WITH PROLONGED VERTICAL ASCENT...IT IS QUITE PROBABLE A FEW LOCATION ALONG AND SOUTH OF I-80 WILL EXPERIENCE HEFTY RAINFALL AMOUNTS BY EVENTS END THURSDAY AFTN. .LONG TERM...(FRIDAY NIGHT THROUGH TUESDAY) ISSUED AT 315 PM CDT TUE SEP 30 2014 NO SIGNIFICANT CHANGES NEEDED IN THE EXTENDED PDS AS BOTH GFS/ECM MAINTAIN DRY CONDITIONS THRU THE WEEKEND AND INTO EARLY NEXT WEEK. WITH UPSTREAM RIDGE AMPLIFYING OVER THE WRN CONUS...EXPECT INCREASING THKNS TO BUILD IN FROM THE WEST THUS ALLOWING FOR A RATHER NICE FALL TYPE CONDITIONS NEXT WEEKEND AND INTO EARLY NEXT WEEK. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1220 PM CDT TUE SEP 30 2014 MVFR CEILINGS AND LOCAL IFR VSBYS POSSIBLE THROUGH THE AFTERNOON WITH SHRA/TSRA. PCPN MAY NOT AFFECT KOFK TOO MUCH TONIGHT BUT DID ADD IN IFR CEILINGS AND VSBYS. THE LOW CLOUDS AND FOG MAY ALSO AFFECT KLNK AND KOMA LATER TONIGHT AFTER PCPN ENDS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...DEE LONG TERM...DEE AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1220 PM CDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1220 PM CDT TUE SEP 30 2014 SEVERE RISK IN NORTHEAST NEBRASKA WAS CONDITIONAL AND AGREE WITH THE LATEST SPC DAY 1 OUTLOOK. WE MAY STILL HAVE A FEW STRONG STORMS AROUND. TEMPERATURES ARE HIGHLY DEPENDENT ON PCPN. AHEAD OF THE PCPN AREA IT HAS WARMED INTO THE LOWER 80S IN FAR SOUTHEAST NEBRASKA AND SOUTHWEST IOWA. WHERE PCPN IS CURRENTLY FALLING IT IS IN THE 60S. EXPECT PCPN TO CONTINUE IN OUR SOUTHERN AND EASTERN ZONES THIS AFTERNOON. THERE MAY BE A BREAK LATE AFTERNOON/EARLY EVENING THEN MORE OVERNIGHT. && .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 PRIMARY CONCERN WILL BE DEALING WITH TIMING OF PRECIP EVENTS TODAY THROUGH THURSDAY AS SERIES OF UPPER WAVES MOVE ACROSS THE REGION. INITIAL SHORT WAVE ASSOCIATED WITH CLOSED UPPER LOW OVER SOUTHEAST WYOMING WAS LIFTING INTO CENTRAL NEBRASKA AT 07Z. SUPPORTED BY 60KT MID LEVEL SPEED MAX OVER WESTERN NEBRASKA. CONVECTION HAD WEAKENED AND DIMINISHED SINCE 05Z AS BAND OF STORMS MOVED AWAY FROM SUPPORT OF 60KT MID LEVEL SPEED MAX OVER NORTHWEST NEBRASKA. 06Z RAP TRANSLATES THIS BAND OF STRONGER WINDS TO THE EAST DURING THE MORNING AND INTO EASTERN SOUTH DAKOTA AND EASTERN NEBRASKA BY EARLY AFTERNOON. EXPECT POPS TO INCREASE ACROSS THE AREA DURING THIS TIME WITH SHORT RANGE MODELS SUGGESTING INITIAL BAND OF STORMS STRETCHING FROM NORTHEAST NEBRASKA INTO NORTH CENTRAL KANSAS BY 18Z IN ADVANCE OF DRY LINE. BIG QUESTION WILL BE WHETHER CLOUDS BREAK ENOUGH FOR SUN TO ADD TO DESTABILIZATION NEAR THE DRY LINE IN NORTHEAST NEBRASKA WHERE SPC HAS SLIGHT RISK IN PLACE. AS THE CLOSED LOW OVER THE WEST LIFTS INTO THE NORTHERN PLAINS TONIGHT AND SURFACE BOUNDARY STALLS NEAR WESTERN EDGE OF THE AREA ADDITIONAL PERIODS OF THUNDERSTORMS ARE EXPECTED INTO THURSDAY AS ANOTHER AMPLIFYING UPPER WAVE APPROACHES FROM THE NORTHERN ROCKIES. PRIMARY FORCING FINALLY SHIFTS EAST WITH THE UPPER WAVE AND SURFACE FRONT LATE THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 TEMPERATURES WILL BE THE MAIN FOCUS IN THE EXTENDED PERIOD. COOLER TEMPERATURES MOVE INTO THE AREA BEHIND THE DEPARTING SHORT TERM WEATHER SYSTEM THURSDAY NIGHT INTO SATURDAY AS YET ANOTHER STRONG WAVE TRACKS THROUGH THE UPPER MIDWEST AND PULLS DOWN COLDER AIR IN ITS WAKE. WARMER TEMPS RETURN FOR THE REMAINDER OF THE PERIOD AS MEAN TROUGH SETS OVER THE EASTERN PART OF THE NATION WITH RIDGING IN THE WEST. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1220 PM CDT TUE SEP 30 2014 MVFR CEILINGS AND LOCAL IFR VSBYS POSSIBLE THROUGH THE AFTERNOON WITH SHRA/TSRA. PCPN MAY NOT AFFECT KOFK TOO MUCH TONIGHT BUT DID ADD IN IFR CEILINGS AND VSBYS. THE LOW CLOUDS AND FOG MAY ALSO AFFECT KLNK AND KOMA LATER TONIGHT AFTER PCPN ENDS. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...MILLER SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...MILLER
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
641 AM CDT TUE SEP 30 2014 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 PRIMARY CONCERN WILL BE DEALING WITH TIMING OF PRECIP EVENTS TODAY THROUGH THURSDAY AS SERIES OF UPPER WAVES MOVE ACROSS THE REGION. INITIAL SHORT WAVE ASSOCIATED WITH CLOSED UPPER LOW OVER SOUTHEAST WYOMING WAS LIFTING INTO CENTRAL NEBRASKA AT 07Z. SUPPORTED BY 60KT MID LEVEL SPEED MAX OVER WESTERN NEBRASKA. CONVECTION HAD WEAKENED AND DIMINISHED SINCE 05Z AS BAND OF STORMS MOVED AWAY FROM SUPPORT OF 60KT MID LEVEL SPEED MAX OVER NORTHWEST NEBRASKA. 06Z RAP TRANSLATES THIS BAND OF STRONGER WINDS TO THE EAST DURING THE MORNING AND INTO EASTERN SOUTH DAKOTA AND EASTERN NEBRASKA BY EARLY AFTERNOON. EXPECT POPS TO INCREASE ACROSS THE AREA DURING THIS TIME WITH SHORT RANGE MODELS SUGGESTING INITIAL BAND OF STORMS STRETCHING FROM NORTHEAST NEBRASKA INTO NORTH CENTRAL KANSAS BY 18Z IN ADVANCE OF DRY LINE. BIG QUESTION WILL BE WHETHER CLOUDS BREAK ENOUGH FOR SUN TO ADD TO DESTABILIZATION NEAR THE DRY LINE IN NORTHEAST NEBRASKA WHERE SPC HAS SLIGHT RISK IN PLACE. AS THE CLOSED LOW OVER THE WEST LIFTS INTO THE NORTHERN PLAINS TONIGHT AND SURFACE BOUNDARY STALLS NEAR WESTERN EDGE OF THE AREA ADDITIONAL PERIODS OF THUNDERSTORMS ARE EXPECTED INTO THURSDAY AS ANOTHER AMPLIFYING UPPER WAVE APPROACHES FROM THE NORTHERN ROCKIES. PRIMARY FORCING FINALLY SHIFTS EAST WITH THE UPPER WAVE AND SURFACE FRONT LATE THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 TEMPERATURES WILL BE THE MAIN FOCUS IN THE EXTENDED PERIOD. COOLER TEMPERATURES MOVE INTO THE AREA BEHIND THE DEPARTING SHORT TERM WEATHER SYSTEM THURSDAY NIGHT INTO SATURDAY AS YET ANOTHER STRONG WAVE TRACKS THROUGH THE UPPER MIDWEST AND PULLS DOWN COLDER AIR IN ITS WAKE. WARMER TEMPS RETURN FOR THE REMAINDER OF THE PERIOD AS MEAN TROUGH SETS OVER THE EASTERN PART OF THE NATION WITH RIDGING IN THE WEST. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 637 AM CDT TUE SEP 30 2014 LINE OF SCATTERED SHOWERS AND THUNDERSTORMS WILL SLOWLY DRIFT EAST THIS MORNING...AFFECTING KOFK BETWEEN 12Z AND 16Z...AND KLNK BETWEEN 15Z AND 20Z. IF LINE HOLDS TOGETHER...EXPECT SHOWERS AND STORMS AT KOMA AFTER 18Z. CIGS WILL LIKELY REMAIN GENERALLY VFR WITH MVFR VSBYS COMMON IN PRECIPITATION. EXPECT A FEW HOURS OF NO PRECIP BETWEEN ABOUT 20Z AND 00Z...BUT MORE STORMS ARE EXPECTED TO FIRE ALONG A FRONT SHORTLY AFTER 00Z. SOME STRONG STORMS ARE POSSIBLE IN KOFK NEAR 00Z...AND IN THE KLNK AND KOMA AREAS AFTER 04Z. ATTENDANT MVFR/IFR CIGS/VSBYS CAN BE EXPECTED WITH THIS ACTIVITY. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS HASTINGS NE
401 AM CDT TUE SEP 30 2014 ...THE END OF THIS CURRENT STRETCH OF SUMMERLIKE WARMTH IS ON THE HORIZON AND THE TRANSITION TO A TEMPORARY COOLDOWN WILL OCCUR WITH MULTIPLE CHANCES FOR SHWRS/TSTMS THRU THURSDAY... .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 401 AM CDT TUE SEP 30 2014 ALOFT: A POTENT VORT MAX WAS OVER THE PANHANDLE AT 09Z WITH A NICE COMMA CLOUD IN SATELLITE. THIS VORT MAX WILL CONT DEPARTING THE REGION TO THE NNE. THE SUBSIDENCE AND DRY SLOT IN ITS WAKE WILL WRAP INTO THE FCST AREA TODAY. THE NEXT SHORTWAVE TROF WAS OVER THE PACIFIC NW. THIS TROF WILL CROSS THE INTERMOUNTAIN W TODAY...WITH THE SRN MOST VORT MAX MOVING INTO CO THIS EVENING AND EJECTING NE ACROSS KS/NEB AFTER MIDNIGHT. SURFACE: DEEPENING LOW PRES WAS OVER THE PANHANDLE AND WILL HEAD NNE ACROSS THE DAKOTAS TODAY-TONIGHT. IN ITS WAKE A WEAK COOL FRONT WILL MOVE INTO CNTRL NEB/KS AND BECOME STATIONARY THRU TONIGHT. AM NOT EVEN SURE THIS IS A TRUE FRONT. IT APPEARS TO BE MORE OF A MODEST DRYLINE. OVER THE PAST FEW HRS...THE HRRR HAS BEEN STELLAR WITH ITS DEPICTION OF THE DECREASE IN SHWR/TSTM ACTIVITY WITHIN THE SE QUADRANT OF THE COMMA CLOUD. FROM REGIONAL 00Z SOUNDINGS IT APPEARED THERE WAS TOO MUCH CAPPING ALOFT AND POOR MID-LVL LAPSE RATES /LACK OF INSTABILITY/. THRU SUNRISE: A FEW ISOLATED SHWRS WILL CONT TO POP UP HERE AND THERE. WE ARE CURRENTLY MONITORING THE TSTM CLUSTER IN THE DDC AREA. THE 06Z NAM/HRRR AND THE 00Z HI-RES NAM GUIDANCE ALL HAVE IT AND TAKE IT NE INTO THE FCST AREA...MAINLY E OF HWY 281. SO WHILE POPS WERE INITIALLY TRIMMED THRU MIDDAY BASED ON RADAR TRENDS...THEY WERE RAMPED BACK UP BASED ON GOOD GUIDANCE HANDLING OF THIS. TODAY: SHWRS WITH EMBEDDED THUNDER UNTIL NOON WITH A DRYING TREND FROM W-E. WE SHOULD SEE A BREAK EARLY THIS AFTERNOON...THEN THERE IS POTENTIAL FOR AN ISOLATED TSTM OR TWO TO REDEVELOP. MOST LOCATIONS WILL REMAIN DRY. ANOTHER DAY OF WARMER THAN NORMAL TEMPS. HOWEVER...CONFIDENCE IN HIGHS IS BELOW AVERAGE E OF HWY 281. IF MORNING CLOUDS/SHWRS ARE MORE EXTENSIVE THAN EXPECTED...WE MAY BE TOO HIGH BY 3-5F DUE TO DELAYED CLEARING. WE WILL CLOSE THE BOOKS ON A COOLER THAN NORMAL SEP TODAY...BUT THE LAST 4 DAYS OF AVERAGE TEMPS AT LEAST 10F ABOVE NORMAL PUT A BIG DENT IN THE DOWNSIDE DEPARTURE FROM NORMAL. THAT RECORD COOL STRETCH FROM THE 11TH-13TH WAS TOUGH TO RECOVER FROM FOR THE MONTHLY AVERAGE TEMP. DEWPOINTS WILL INCREASE AHEAD OF THE BOUNDARY /E OF HWY 281/ IN THE WAKE OF THIS MORNING`S SHWRS. COMBINED WITH COOLING ALOFT BEHIND THE DEPARTING TROF ALOFT...THIS WILL RESULT IN MODEST DESTABILIZATION WITH A SWATH OF MLCAPE UP TO 1250 J/KG THIS AFTERNOON. WITH LITTLE IN THE WAY OF CINH...CONVERGENCE ALONG THE BOUNDARY SHOULD BE ENOUGH TO INITIATE A COUPLE TSTMS. MOST OF THE TSTMS ACTIVITY SHOULD BE OVER ERN NEB/KS. EFFECTIVE SHEAR WILL BE 35-40 KTS...SUFFICIENT FOR ORGANIZED UPDRAFTS. GIVEN A DECENT COMPONENT OF DEEP LAYER WINDS NORMAL TO THE FORCING...AND THE EXPECTED LACK OF COMPETITION...STORMS COULD BE SUPERCELLULAR IN CHARACTER. THE SKINNY CAPE PROFILE SUGGESTS MODEST SEVERE HAIL BUT INTERNAL UPDRAFT ENHANCEMENT IN ANY SUPERCELLS WILL TRUMP THIS. FOR NOW HAVE CONTINUED MENTION OF 1" HAIL IN THE HWO. THREAT FOR DAMAGING WIND IS THERE BUT NOT AS GREAT. TONIGHT: THE APPROACH OF THE NEXT TROF AND THE ASSOCIATED EXIT REGION OF AN 80 KT UPPER-LVL JET STREAK WILL INCREASE THE RISK FOR ADDITIONAL TSTM DEVELOPMENT...MAINLY OVER ERN KS/NEB. HOWEVER... THE WRN FRINGE OF THIS ACTIVITY COULD STILL AFFECT A FEW LOCATIONS E OF HWY 281. MUCAPE NO GREATER THAN 1000 J/KG. SHEAR IN THE CLOUD- BEARING LAYER WILL BE NEAR 30 KTS. SO HAIL UP TO THE SIZE OF NICKELS CANT BE RULED OUT. MOST LOCATIONS WILL REMAIN DRY. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 401 AM CDT TUE SEP 30 2014 WEDNESDAY AND THURSDAY WILL BE THE MOST ACTIVE WEATHERWISE DURING THE EXTENDED PERIODS...THEN CONDITIONS DRY OUT FOR THE WEEKEND/EARLY NEXT WEEK. CONVECTION WHICH DEVELOPS TUESDAY NIGHT MAY LINGER BRIEFLY IN OUR SOUTHEAST ZONES WEDNESDAY MORNING ALONG DEPARTING TROUGH AXIS AND NOSE OF THE LLVL JET. THE DAYTIME HOURS WILL BE FAIRLY QUIET WITH MILD TEMPERATURES...RISING INTO THE MID/UPPER 70S FOR HIGHS. THE WEATHER PATTERN WILL BE UNDERGOING CHANGES DURING THE DAY AS AN UPSTREAM TROUGH TRANSLATES SOUTHEAST THROUGH THE ROCKIES. THE ASSOCIATED SFC LOW DEEPENS IN SOUTHEAST CO/OK PANHANDLE AREA WITH A WARM FRONTAL BOUNDARY STRETCHING NORTHEAST INTO EASTERN NEB...AND A COLD FRONTAL BOUNDARY WILL ADVANCE FROM THE HIGH PLAINS. MOISTURE ADVECTS NORTHWARD AND POOLS ALONG THE WARM FRONTAL BOUNDARY ACROSS KS/SOUTHERN NEB WITH DPS AVERAGING IN THE MID 60S. INSTABILITY INCREASES TO AROUND 2500 J/KG IN AFTN IN OUR SE ZONES PER SREF AND NAM SUGGESTS THIS COULD BE EVEN HIGHER. DEEP LAYER SHEAR AVERAGES 40KTS AND CONDITIONS WILL BE FAVORABLE FOR CONVECTION/SEVERE WEATHER DURING THE AFTN/EVE WITH CONVERGENCE ALONG THE BOUNDARIES AND INCREASING UPPER DYNAMICS AS JET CROSSES KS AND THE TROUGH EDGES ONTO THE PLAINS. THE OVERNIGHT HOURS ARE LOOKING WET WITH WAA AHEAD OF THE APPROACHING TROUGH AND GOOD MIDLEVEL FRONTOGENESIS WITH THE ADVANCING COLD FRONT. THERE ARE STILL SOME MODEL DIFFERENCES ON HOW LONG PCPN WILL LAST ON THURSDAY WITH THE NAM SLOWER WITH TROUGH PROGRESSION AND CLOSES OFF THE LOW AT H7...WHEREAS OTHER MODELS MAINTAIN MORE OF AN OPEN WAVE/MORE PROGRESSIVE SOLUTION DURING THE DAY. HARD TO SAY AT THIS POINT...BUT THE MORNING HOURS LOOKING MORE WET THAN THE AFTERNOON BUT CONFIDENCE IS LOW SO WILL NOT TRY TO PINPOINT TIMING JUST YET IN CASE SYSTEM SLOWS. THE FORECAST DRIES OUT THURSDAY NIGHT BEHIND THE TROUGH AXIS WITH COOLER TEMPS MOVING IN WITH CAA IN NW FLOW AS THE UPPER TROUGH DEEPENS FM THE UPPER MIDWEST THRU THE OHIO VALLEY. OVER THE WEEKEND HEIGHTS RISE AND TEMPS BEGIN TO MODERATE AS THE EASTERN TROUGH LIFTS ACROSS THE NE CONUS/ONTARIO AND MEANDERS AROUND THE HUDSON BAY. OVERALL TEMPS ARE LOOKING FAIRLY SEASONAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1253 AM CDT TUE SEP 30 2014 THRU 11Z: VFR MID-LEVEL CIGS AROUND 8K FT...BUT THERE WILL BE A 2 HR WINDOW FOR MVFR VSBYS IN SCT +SHRA WITH POTENTIAL FOR G35 KTS. THE TIMING TOOL BASED ON RADAR SUGGESTS 630Z-0800Z AT EAR AND 07Z-09Z GRI. AFTER THE LINE OF SHWRS CLEARS THE TERMINALS...SKIES WILL CLEAR WITH LLWS DEVELOPING. OUTSIDE OF THESE SHWRS...WINDS WILL BE SE AROUND 10 KTS. CONFIDENCE: HIGH TUE: VFR. LLWS ENDS 14Z-15Z. A FEW CU COULD DEVELOP WITH DAYTIME HEATING. SE WINDS WILL BECOME S OR POSSIBLY SSW 10-15 KTS. CONFIDENCE: HIGH THIS EVENING: VFR. WINDS WILL BECOME SSE 5-10 KTS. CONFIDENCE:HIGH && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ SHORT TERM...HALBLAUB LONG TERM...FAY AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
307 AM CDT TUE SEP 30 2014 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 PRIMARY CONCERN WILL BE DEALING WITH TIMING OF PRECIP EVENTS TODAY THROUGH THURSDAY AS SERIES OF UPPER WAVES MOVE ACROSS THE REGION. INITIAL SHORT WAVE ASSOCIATED WITH CLOSED UPPER LOW OVER SOUTHEAST WYOMING WAS LIFTING INTO CENTRAL NEBRASKA AT 07Z. SUPPORTED BY 60KT MID LEVEL SPEED MAX OVER WESTERN NEBRASKA. CONVECTION HAD WEAKENED AND DIMINISHED SINCE 05Z AS BAND OF STORMS MOVED AWAY FROM SUPPORT OF 60KT MID LEVEL SPEED MAX OVER NORTHWEST NEBRASKA. 06Z RAP TRANSLATES THIS BAND OF STRONGER WINDS TO THE EAST DURING THE MORNING AND INTO EASTERN SOUTH DAKOTA AND EASTERN NEBRASKA BY EARLY AFTERNOON. EXPECT POPS TO INCREASE ACROSS THE AREA DURING THIS TIME WITH SHORT RANGE MODELS SUGGESTING INITIAL BAND OF STORMS STRETCHING FROM NORTHEAST NEBRASKA INTO NORTH CENTRAL KANSAS BY 18Z IN ADVANCE OF DRY LINE. BIG QUESTION WILL BE WHETHER CLOUDS BREAK ENOUGH FOR SUN TO ADD TO DESTABILIZATION NEAR THE DRY LINE IN NORTHEAST NEBRASKA WHERE SPC HAS SLIGHT RISK IN PLACE. AS THE CLOSED LOW OVER THE WEST LIFTS INTO THE NORTHERN PLAINS TONIGHT AND SURFACE BOUNDARY STALLS NEAR WESTERN EDGE OF THE AREA ADDITIONAL PERIODS OF THUNDERSTORMS ARE EXPECTED INTO THURSDAY AS ANOTHER AMPLIFYING UPPER WAVE APPROACHES FROM THE NORTHERN ROCKIES. PRIMARY FORCING FINALLY SHIFTS EAST WITH THE UPPER WAVE AND SURFACE FRONT LATE THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH MONDAY) ISSUED AT 305 AM CDT TUE SEP 30 2014 TEMPERATURES WILL BE THE MAIN FOCUS IN THE EXTENDED PERIOD. COOLER TEMPERATURES MOVE INTO THE AREA BEHIND THE DEPARTING SHORT TERM WEATHER SYSTEM THURSDAY NIGHT INTO SATURDAY AS YET ANOTHER STRONG WAVE TRACKS THROUGH THE UPPER MIDWEST AND PULLS DOWN COLDER AIR IN ITS WAKE. WARMER TEMPS RETURN FOR THE REMAINDER OF THE PERIOD AS MEAN TROUGH SETS OVER THE EASTERN PART OF THE NATION WITH RIDGING IN THE WEST. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1125 PM CDT MON SEP 29 2014 A WEAK BACK-DOOR FRONT THAT WAS PUSHING WEST TOWARD MISSOURI RIVER SHOULD WASH OUT TONIGHT AS SRLY LOW LEVEL JET INCREASES AHEAD OF A LARGE UPPER TROUGH. HOWEVER...A FEW LOW CLOUDS WITH CIGS BELOW FL010 WERE WORKING SW WITH THE BOUNDARY LAYER WINDS AND THESE LOW CIGS COULD BRIEFLY IMPACT KOMA AND KOFK. OTHERWISE THUNDERSTORMS ARE STILL LIKELY TO ROLL INTO ERN NEBRASKA LATE TONIGHT THROUGH MID TUESDAY MORNING AS TROUGH CONTINUES LIFTING NE. ALTHOUGH THERE IS SOME CHANCE THESE STORMS COULD LINGER MUCH OF THE DAY...IT APPEARED THERE WILL BE ONE WAVE WORKING TOWARD THE MO RIVER THROUGH MIDDAY WITH REDEVELOPMENT THEN LATER IN THE DAY ACROSS TWO AREAS. ONE AREA POSSIBLY NEAR KOFK BY LATE AFTN WITH THE OTHER NEAR OR SW OF KLNK A LITTLE LATER WITH THAT SECOND AREA POSSIBLY IMPACTING KLNK AND KOMA LONGER THAN THE FIRST AREA WOULD AT KOFK. SEVERE STORMS ARE POSSIBLE...ESPECIALLY IF BREAKS IN MORNING CONVECTION ALLOW TEMPS TO RECOVER WELL THROUGH THE 70S. FOR NOW JUST CONTINUED THE MENTION OF PROB30 WITH GUSTS TO 35 WITH LATTER DAY CONVECTION CHANCES AT ALL SITES. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1253 AM CDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1208 AM CDT TUE SEP 30 2014 SEVERAL MINOR UPDATES HAVE BEEN PUBLISHED SINCE 10 PM...PRIMARILY FOR POPS/SKY. THE NARROW RAIN BAND IS BEGINNING TO FALL APART AS INDICATED BY THE HRRR. SO POPS WERE BACKED DOWN A BIT AND WE ARE PROBABLY STILL OVERDONE IF THE HRRR IS RIGHT. WE HAVE SEEN G36 KTS AT MKC AND 39 KTS AT LBF. AN SPS WAS POSTED FOR FURNAS COUNTY AT 11 PM. WE WILL CONT TO MONITOR WIND GUSTS AND FURTHER SPECIAL WX STMTS /SPS/ MAY BE NEEDED THRU THE NIGHT. BUT THIS WILL BE CONTINGENT ON THE SHWRS HOLDING TOGETHER. NO OTHER CHANGES NEEDED. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 323 PM CDT MON SEP 29 2014 UPPER AIR AND SATELLITE DATA SHOWING THE MAIN LOW PRESSURE SYSTEM OVER THE ROCKIES...WITH THE SRN LOBE OF ENERGY SWINGING THROUGH CO/NM...WHILE SHORTWAVE RIDGING AHEAD OF THE SYSTEM HAS HELPED TO KEEP THINGS QUIET ACROSS THE CWA TODAY. AT THE SFC...HAVE HAD AT TIMES GUSTY SRLY WINDS ACROSS THE CWA...WITH LOW PRESSURE SET UP OVER ERN CO...WITH A FRONTAL BOUNDARY EXTENDING EAST ACROSS NRN NEB. STARTED THE DAY OUT WITH MOSTLY CLEAR SKIES...BUT CU DEVELOPED BY MIDDAY BRINGING AT LEAST PARTLY CLOUDY SKIES FOR THIS AFTERNOON. 3PM TEMPS SHOWING LOWER/MID 80S ACROSS THE CWA. THE PRIMARY FORECAST CONCERN IS WITH THAT PIECE OF ENERGY CURRENTLY MOVING THROUGH CO/NM...AND THE ACCOMPANYING SHOWER/THUNDERSTORM CHANCES. 12Z MODELS AND LATEST RAP/HRRR DATA CONTINUING THE TREND OF A LATER ARRIVAL OF PRECIP CHANCES...AND KEPT THE 00-03Z HOURS DRY UNTIL THE BETTER FORCING ARRIVES. OVERALL...DIDNT MAKE ANY SIGNIFICANT CHANGES TO THE INHERITED FORECAST...WITH POPS ESP RAMPING UP IN COVERAGE AFTER 06Z IN THE WEST...THEN SHIFTING EAST THROUGH THE REST OF THE OVERNIGHT HOURS. NEAR/AFTER SUNRISE...THE BETTER FOCUS FOR PRECIP IS EXPECTED TO HAVE SHIFTED TO THE ERN HALF OF THE CWA...AND GRADUALLY SLIDE OFF TO THE EAST. THUNDERSTORM CHANCES WILL LINGER ACROSS FAR SERN PORTIONS OF THE CWA INTO THE LATE AFTERNOON HOURS. THE MAIN AXIS OF INSTABILITY CURRENTLY SITS TO THE W AND N OF THE CWA...AND THROUGH THE OVERNIGHT HOURS...MODELS VARY ON WHAT IS AVAILABLE ACROSS THE CWA. THE NAM CONTINUES TO BE THE MOST AGGRESSIVE...SHOWING SOME MUCAPE VALUES NEAR/ABOVE 1000 J/KG...OTHERS ARE CLOSER TO 500 J/KG. SHOULD THOSE HIGHER VALUES MATERIALIZE THERE WILL BE MORE CONCERN FOR SEVERE WEATHER...THINKING THAT WIND GUSTS NEAR 60 MPH WOULD BE THE PRIMARY THREAT...ALONG WITH SMALL HAIL. OVERNIGHT LOWS TONIGHT ARE FORECAST TO RANGE FROM THE MID 50S TO LOWER 60S...WITH MID 70S TO LOW 80S FOR HIGHS TOMORROW. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 323 PM CDT MON SEP 29 2014 AN ACTIVE WEATHER PERIOD...ESPECIALLY WEDNESDAY AND THURSDAY. BY FRIDAY...THE AREA SETTLES INTO A NORTHWEST FLOW REGIME WHICH SHOULD BRING PRIMARILY DRY AND COOLER CONDITIONS THROUGH THE WEEKEND. STARTING TUESDAY EVENING...WE WILL KNOW BY SUNSET IF SOME LATE AFTERNOON THUNDERSTORMS CAN FIRE ALONG SOUTHERN END OF SHORTWAVE ENERGY SLOWING SLIDING EAST DURING THE DAY. THIS WOULD PRIMARILY IMPACT THE EXTREME SOUTHEAST PART OF THE FORECAST AREA...AND HAVE CONTINUED WITH 20 TO 30 PERCENT STORM CHANCES IN THAT VICINITY THROUGH EVENING/OVERNIGHT HOURS. WEDNESDAY PROBABLY STARTS OFF PRETTY QUIET BUT THE EMERGENCE OF A MID LEVEL SHORT WAVE...AND THE PRESENCE OF A LINGERING SURFACE BOUNDARY ACROSS THE SOUTHERN PART OF THE FORECAST AREA WILL MAKE FOR INCREASING SHOWER/STORM CHANCES THROUGH THE DAY. OF NOTE... IS THE RISK FOR STRONG TO SEVERE THUNDERSTORMS LATE IN THE DAY OR VERY EARLY EVENING WEDNESDAY...PRIMARILY FIRING ALONG WEAK FRONTAL BOUNDARY WHICH IS SUPPOSED TO BE NEAR THE KS/NE BORDER BY LATE AFTERNOON. CAPPING IS WEAK...AND INSTABILITY IS SUFFICIENT FOR THUNDERSTORMS TO DEVELOP. MID-LEVEL SHEAR IS STRONG AND SUPPORTED OF SOME STRONG/SEVERE THUNDERSTORMS ACROSS THE SOUTHERN 1/3 OF THE FORECAST AREA. MIGHT BE A LITTLE BIT EARLY TO REALLY NAIL DOWN THIS POTENTIAL EXACTLY BUT ENOUGH IN THE MODELS TO CONSIDER THE SEVERE RISK AND ITS POTENTIAL. BACKING FLOW NEAR BOUNDARY COULD MAKE THINGS INTERESTING FOR A COUPLE HOURS IF THE STORMS CAN FIRE. THAT SHOULD BE CONFINED TO A SMALL AREA NEAR THE BOUNDARY AND FOR A COUPLE HOURS AT MOST. WHAT STORMS DO DEVELOP...WILL CONTINUE INTO THE NIGHT TIME HOURS AND SHIFT EAST WITH LOW LEVEL JET. THURSDAY IS A BIT OF QUANDARY AT THIS POINT. LATEST MODEL RUNS PRETTY MUCH ALL CAME IN BACK FURTHER NORTH NEBRASKA. EVEN THE FURTHEST NORTH GFS SHIFTED THINGS TO NORTHERN NEBRASKA. THIS IS BASICALLY ASSOCIATED WITH THE MAIN TROUGH MOVING THROUGH DURING THE 1/2 HALF OF THE DAY. HAVE CONTINUED 20 TO 40 PERCENT RAIN CHANCES...BUT THAT COULD GO UP QUITE A BIT IF THINGS PAN OUT DIFFERENTLY. OF COURSE...IT COULD SHIFT BACK FURTHER SOUTH AND BE MORE OF AN INFLUENCE ACROSS NORTH CENTRAL KANSAS DURING THE DAY. EITHER WAY...LOOKS LIKE TEMPERATURES HOLD IN THE 60S. DON/T BE SURPRISED IF PRECIPITATION CHANCES CHANGE FROM RUN-TO-RUN FOR THURSDAY FOR THE NEXT COUPLE OF RUNS. THE REST OF THE FORECAST FROM FRIDAY THROUGH MONDAY IS CURRENTLY PROJECTED AS DRY. THE UPPER FLOW STAYS NORTHWEST ALTHOUGH THERE SIGNS IT MAY SHIFT WESTERLY WITH TIME. COUPLE OF HINTS AT MAYBE A NORTHWEST FLOW SHOWER/SPRINKLE/TRACE EVENT...BUT WILL LEAVE DRY FOR NOW. TEMPERATURES/CONDITIONS LOOK VERY SEASONAL FOR THE FIRST PART OF OCTOBER. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z TUESDAY NIGHT) ISSUED AT 1253 AM CDT TUE SEP 30 2014 THRU 11Z: VFR MID-LEVEL CIGS AROUND 8K FT...BUT THERE WILL BE A 2 HR WINDOW FOR MVFR VSBYS IN SCT +SHRA WITH POTENTIAL FOR G35 KTS. THE TIMING TOOL BASED ON RADAR SUGGESTS 630Z-0800Z AT EAR AND 07Z-09Z GRI. AFTER THE LINE OF SHWRS CLEARS THE TERMINALS...SKIES WILL CLEAR WITH LLWS DEVELOPING. OUTSIDE OF THESE SHWRS...WINDS WILL BE SE AROUND 10 KTS. CONFIDENCE: HIGH TUE: VFR. LLWS ENDS 14Z-15Z. A FEW CU COULD DEVELOP WITH DAYTIME HEATING. SE WINDS WILL BECOME S OR POSSIBLY SSW 10-15 KTS. CONFIDENCE: HIGH THIS EVENING: VFR. WINDS WILL BECOME SSE 5-10 KTS. CONFIDENCE:HIGH && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...ADP LONG TERM...MORITZ AVIATION...HALBLAUB
AREA FORECAST DISCUSSION
NWS HASTINGS NE
1208 AM CDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1208 AM CDT TUE SEP 30 2014 SEVERAL MINOR UPDATES HAVE BEEN PUBLISHED SINCE 10 PM...PRIMARILY FOR POPS/SKY. THE NARROW RAIN BAND IS BEGINNING TO FALL APART AS INDICATED BY THE HRRR. SO POPS WERE BACKED DOWN A BIT AND WE ARE PROBABLY STILL OVERDONE IF THE HRRR IS RIGHT. WE HAVE SEEN G36 KTS AT MKC AND 39 KTS AT LBF. AN SPS WAS POSTED FOR FURNAS COUNTY AT 11 PM. WE WILL CONT TO MONITOR WIND GUSTS AND FURTHER SPECIAL WX STMTS /SPS/ MAY BE NEEDED THRU THE NIGHT. BUT THIS WILL BE CONTINGENT ON THE SHWRS HOLDING TOGETHER. NO OTHER CHANGES WERE NEEDED. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 323 PM CDT MON SEP 29 2014 UPPER AIR AND SATELLITE DATA SHOWING THE MAIN LOW PRESSURE SYSTEM OVER THE ROCKIES...WITH THE SRN LOBE OF ENERGY SWINGING THROUGH CO/NM...WHILE SHORTWAVE RIDGING AHEAD OF THE SYSTEM HAS HELPED TO KEEP THINGS QUIET ACROSS THE CWA TODAY. AT THE SFC...HAVE HAD AT TIMES GUSTY SRLY WINDS ACROSS THE CWA...WITH LOW PRESSURE SET UP OVER ERN CO...WITH A FRONTAL BOUNDARY EXTENDING EAST ACROSS NRN NEB. STARTED THE DAY OUT WITH MOSTLY CLEAR SKIES...BUT CU DEVELOPED BY MIDDAY BRINGING AT LEAST PARTLY CLOUDY SKIES FOR THIS AFTERNOON. 3PM TEMPS SHOWING LOWER/MID 80S ACROSS THE CWA. THE PRIMARY FORECAST CONCERN IS WITH THAT PIECE OF ENERGY CURRENTLY MOVING THROUGH CO/NM...AND THE ACCOMPANYING SHOWER/THUNDERSTORM CHANCES. 12Z MODELS AND LATEST RAP/HRRR DATA CONTINUING THE TREND OF A LATER ARRIVAL OF PRECIP CHANCES...AND KEPT THE 00-03Z HOURS DRY UNTIL THE BETTER FORCING ARRIVES. OVERALL...DIDNT MAKE ANY SIGNIFICANT CHANGES TO THE INHERITED FORECAST...WITH POPS ESP RAMPING UP IN COVERAGE AFTER 06Z IN THE WEST...THEN SHIFTING EAST THROUGH THE REST OF THE OVERNIGHT HOURS. NEAR/AFTER SUNRISE...THE BETTER FOCUS FOR PRECIP IS EXPECTED TO HAVE SHIFTED TO THE ERN HALF OF THE CWA...AND GRADUALLY SLIDE OFF TO THE EAST. THUNDERSTORM CHANCES WILL LINGER ACROSS FAR SERN PORTIONS OF THE CWA INTO THE LATE AFTERNOON HOURS. THE MAIN AXIS OF INSTABILITY CURRENTLY SITS TO THE W AND N OF THE CWA...AND THROUGH THE OVERNIGHT HOURS...MODELS VARY ON WHAT IS AVAILABLE ACROSS THE CWA. THE NAM CONTINUES TO BE THE MOST AGGRESSIVE...SHOWING SOME MUCAPE VALUES NEAR/ABOVE 1000 J/KG...OTHERS ARE CLOSER TO 500 J/KG. SHOULD THOSE HIGHER VALUES MATERIALIZE THERE WILL BE MORE CONCERN FOR SEVERE WEATHER...THINKING THAT WIND GUSTS NEAR 60 MPH WOULD BE THE PRIMARY THREAT...ALONG WITH SMALL HAIL. OVERNIGHT LOWS TONIGHT ARE FORECAST TO RANGE FROM THE MID 50S TO LOWER 60S...WITH MID 70S TO LOW 80S FOR HIGHS TOMORROW. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 323 PM CDT MON SEP 29 2014 AN ACTIVE WEATHER PERIOD...ESPECIALLY WEDNESDAY AND THURSDAY. BY FRIDAY...THE AREA SETTLES INTO A NORTHWEST FLOW REGIME WHICH SHOULD BRING PRIMARILY DRY AND COOLER CONDITIONS THROUGH THE WEEKEND. STARTING TUESDAY EVENING...WE WILL KNOW BY SUNSET IF SOME LATE AFTERNOON THUNDERSTORMS CAN FIRE ALONG SOUTHERN END OF SHORTWAVE ENERGY SLOWING SLIDING EAST DURING THE DAY. THIS WOULD PRIMARILY IMPACT THE EXTREME SOUTHEAST PART OF THE FORECAST AREA...AND HAVE CONTINUED WITH 20 TO 30 PERCENT STORM CHANCES IN THAT VICINITY THROUGH EVENING/OVERNIGHT HOURS. WEDNESDAY PROBABLY STARTS OFF PRETTY QUIET BUT THE EMERGENCE OF A MID LEVEL SHORT WAVE...AND THE PRESENCE OF A LINGERING SURFACE BOUNDARY ACROSS THE SOUTHERN PART OF THE FORECAST AREA WILL MAKE FOR INCREASING SHOWER/STORM CHANCES THROUGH THE DAY. OF NOTE... IS THE RISK FOR STRONG TO SEVERE THUNDERSTORMS LATE IN THE DAY OR VERY EARLY EVENING WEDNESDAY...PRIMARILY FIRING ALONG WEAK FRONTAL BOUNDARY WHICH IS SUPPOSED TO BE NEAR THE KS/NE BORDER BY LATE AFTERNOON. CAPPING IS WEAK...AND INSTABILITY IS SUFFICIENT FOR THUNDERSTORMS TO DEVELOP. MID-LEVEL SHEAR IS STRONG AND SUPPORTED OF SOME STRONG/SEVERE THUNDERSTORMS ACROSS THE SOUTHERN 1/3 OF THE FORECAST AREA. MIGHT BE A LITTLE BIT EARLY TO REALLY NAIL DOWN THIS POTENTIAL EXACTLY BUT ENOUGH IN THE MODELS TO CONSIDER THE SEVERE RISK AND ITS POTENTIAL. BACKING FLOW NEAR BOUNDARY COULD MAKE THINGS INTERESTING FOR A COUPLE HOURS IF THE STORMS CAN FIRE. THAT SHOULD BE CONFINED TO A SMALL AREA NEAR THE BOUNDARY AND FOR A COUPLE HOURS AT MOST. WHAT STORMS DO DEVELOP...WILL CONTINUE INTO THE NIGHT TIME HOURS AND SHIFT EAST WITH LOW LEVEL JET. THURSDAY IS A BIT OF QUANDARY AT THIS POINT. LATEST MODEL RUNS PRETTY MUCH ALL CAME IN BACK FURTHER NORTH NEBRASKA. EVEN THE FURTHEST NORTH GFS SHIFTED THINGS TO NORTHERN NEBRASKA. THIS IS BASICALLY ASSOCIATED WITH THE MAIN TROUGH MOVING THROUGH DURING THE 1/2 HALF OF THE DAY. HAVE CONTINUED 20 TO 40 PERCENT RAIN CHANCES...BUT THAT COULD GO UP QUITE A BIT IF THINGS PAN OUT DIFFERENTLY. OF COURSE...IT COULD SHIFT BACK FURTHER SOUTH AND BE MORE OF AN INFLUENCE ACROSS NORTH CENTRAL KANSAS DURING THE DAY. EITHER WAY...LOOKS LIKE TEMPERATURES HOLD IN THE 60S. DON/T BE SURPRISED IF PRECIPITATION CHANCES CHANGE FROM RUN-TO-RUN FOR THURSDAY FOR THE NEXT COUPLE OF RUNS. THE REST OF THE FORECAST FROM FRIDAY THROUGH MONDAY IS CURRENTLY PROJECTED AS DRY. THE UPPER FLOW STAYS NORTHWEST ALTHOUGH THERE SIGNS IT MAY SHIFT WESTERLY WITH TIME. COUPLE OF HINTS AT MAYBE A NORTHWEST FLOW SHOWER/SPRINKLE/TRACE EVENT...BUT WILL LEAVE DRY FOR NOW. TEMPERATURES/CONDITIONS LOOK VERY SEASONAL FOR THE FIRST PART OF OCTOBER. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 652 PM CDT MON SEP 29 2014 THE BIGGEST CONCERN WILL BE LOW-LEVEL WIND SHEAR AS THE AXIS OF A LOW-LEVEL JET MOVES EAST. THIS WILL LIKELY ONLY BE A CONCERN FOR A FEW HOURS AS THE JET AXIS CONTINUES EAST FAIRLY QUICKLY. A NARROW CORRIDOR OF SHOWERS AND ISOLATED THUNDERSTORMS WILL MOVE EAST AS WELL...LIKELY LATE TONIGHT INTO EARLY TUESDAY MORNING. INCLUDED VCTS IN THE TAF AS NAILING DOWN A TIME IS DIFFICULT. SO EVEN THROUGH IT IS LIKELY WE WILL GET RAIN FOR A FEW HOURS...I OPTED FOR A LONGER WINDOW OF VCTS. && .GID WATCHES/WARNINGS/ADVISORIES... NE...NONE. KS...NONE. && $$ UPDATE...HALBLAUB SHORT TERM...ADP LONG TERM...MORITZ AVIATION...HEINLEIN
AREA FORECAST DISCUSSION
NWS ELKO NV
310 AM PDT TUE SEP 30 2014 .SYNOPSIS...SHOWERS WILL LINGER ACROSS NORTHERN NEVADA TODAY AND GRADUALLY TAPER OFF. PATCHY FOG IS POSSIBLE THIS MORNING. AS THE WEEK UNFOLDS EXPECT MORE SUNSHINE...PLEASANT AFTERNOON TEMPERATURES AND CHILLY TEMPERATURES IN THE MORNING. THURSDAY MORNING WILL BE NIPPY...A WIDESPREAD FREEZE IS POSSIBLE. THE RIDGE WILL BE DIRECTLY OVER HEAD ON FRIDAY. && .SHORT TERM...TODAY THROUGH WEDNESDAY. AS OF 9Z THE RH AT WMC WAS 100 PERCENT AND 89 PERCENT AT WMC...WITH LIGHT AND CALM WINDS RESPECTIVELY. SENSIBLE WEATHER-WISE...THE SCENARIO IS PRIMED FOR FOG DEVELOPMENT...BUT CAN BE HIT OR MISS BETWEEN BASINS...SO KEPT PATCHY FOG IN THE GRIDS. THE PWS ARE STILL ENHANCED OVER NORTHERN NV TODAY ON THE GFS40. THE HRRR AND NAM CONTINUE TO BRING SHOWERS INTO THE LKN CWA...HOWEVER...SIGNIFICANT QPF NOT ANTICIPATED. NORTHWEST FLOW WILL PERSIST THROUGH MUCH OF THE DAY TRANSITIONING TO NORTHERLY FLOW ON WEDNESDAY. WEDNESDAY SHOULD BE DRY...WITH PWS DIPPING BELOW .30 OF AN INCH. MOST VALLEYS WILL REACH THE 60S WEDNESDAY AFTERNOON...WITH TONOPAH AND GABBS FLIRTING WITH THE 70F BENCHMARK. .LONG TERM...WEDNESDAY NIGHT THROUGH NEXT MONDAY. THE MODELS ARE IN FAIRLY GOOD AGREEMENT WITH AN UPCOMING DRY PATTERN THROUGH THE LONG TERM. AN UPPER LEVEL RIDGE WILL BUILD OVER NEVADA WEDNESDAY NIGHT FOR DRY CONDITIONS. THURSDAY MORNING LOW TEMPERATURES ARE EXPECTED TO BE JUST BELOW FREEZING AT MANY LOCATIONS...ESPECIALLY THE HIGHER VALLEYS OF NORTHEAST NEVADA. THE RIDGE AXIS WILL REMAIN NEAR THE CALIFORNIA COASTLINE...INITIALLY PROVIDING A COOL DRY NORTHWEST FLOW ALOFT. TEMPERATURES WILL REACH INTO THE 70S IN MOST AREAS...TO MAYBE NEAR 80 DEGREES BY THE WEEKEND. LOW TEMPERATURES WILL BE IN THE 30S THROUGH THE SAME PERIOD. && .AVIATION...EXPECT VFR CIGS/VSBY THROUGH THE NEXT 24 HOURS. VCSH WITH LIGHT SPRINKLES POSSIBLE AT THE KEKO/KELY TAF SITES THROUGH THE AFTERNOON. WINDS WILL BE BREEZY WITH GUSTS UP TO 25 KNOTS. && .FIRE WEATHER...LINGERING SHOWERS POSSIBLE TODAY...ESPECIALLY OVER NORTHEASTERN NEVADA. LATER IN THE WEEK A RIDGE WILL MOVE BACK INTO THE WESTERN U.S. RESULTING IN A WARMING AND DRYING TREND. WIDESPREAD HAINES OF 2...AND WITH THIS WEEKENDS HEFTY QPF...IT LOOKS AS THOUGH THE FIRE SEASON OF 2014 IS COMING TO A CLOSE FOR THE WESTERN GREAT BASIN. && .LKN WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 97/86/86/97
AREA FORECAST DISCUSSION
NWS RALEIGH NC
640 AM EDT TUE SEP 30 2014 .SYNOPSIS...WEAK LOW PRESSURE OVER NORTHEAST FLORIDA WILL TRACK NORTHEASTWARD OFF THE SOUTHEAST COAST TODAY. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. A STRONG STORM SYSTEM WILL APPROACH FROM THE WEST ON FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY... UPDATE: FOG HAS BECOME QUITE DENSE OVER MOST OF CENTRAL NC (WITH THE EXCEPTION OF THE FAR SOUTHEAST SECTIONS)... WARRANTING ISSUANCE OF A DENSE FOG ADVISORY UNTIL 10 AM. VSBYS SHOULD GRADUALLY IMPROVE DURING THE 9AM-11AM TIME FRAME. EARLIER DISCUSSION FROM 222 AM TUESDAY... TODAY... FIRST CONCERN EARLY THIS MORNING IS THE DEGREE OF FOG DEVELOPMENT OVER THE AREA THUS FAR. THE MID LEVEL SHORTWAVE TROUGH IS NOW HEADING EAST OFF THE CAROLINA COAST... WITH THE VEIL OF MID/HIGH CLOUDS DEPARTING ALONG WITH IT. THE DAMP GROUND COMBINED WITH THE CLEARING SKIES AND LIGHT/CALM WINDS SHOULD CONTINUE TO FOSTER DEVELOPMENT OF LOW CLOUDS AND FOG EARLY THIS MORNING... ALTHOUGH THE CURRENT PATCHY/FLEETING NATURE OF THESE CONDITIONS (SEVERAL SITES HAVE BOUNCED AROUND BETWEEN 1/4 MI AND 5 MI IN FOG THE LAST FEW HRS) GIVES US PAUSE AS TO THE NEED FOR A DENSE FOG ADVISORY. THE HRRR DEPICTS A FAIRLY SOLID DECK OF LOW CLOUDS/FOG FORMING OVER THE NEXT FEW HOURS HOWEVER. WILL CONTINUE TO MONITOR THE OBSERVED TRENDS. IF VSBYS DO DROP AND HOLD THERE FOR OVER AN HOUR... THEY`RE LIKELY TO HOLD FIRM THROUGH MID MORNING... GIVEN THE WEAK WIND FIELD THROUGH THE LOWEST FEW THOUSAND FEET RESULTING IN MINIMAL STIRRING/DISPERSION HORIZONTALLY OR VERTICALLY. WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY THROUGH MID MORNING TO ACCOUNT FOR THIS. THEN... ONCE HEATING AND SUBSEQUENT MIXING HELPS TO DISPERSE THE FOG/STRATUS... EXPECT A GOOD BIT OF SUNSHINE THROUGH THE DAY... WITH FLAT AFTERNOON STRATOCU LIKELY TO STAY SCATTERED AT WORST. WITH THICKNESSES CLOSE TO SEASONAL NORMALS... STILL LOOK FOR HIGHS WITHIN A FEW DEGREES OF 80. FOR TONIGHT: THE SURFACE LOW TRACKING TOWARD THE NE WELL OFF THE SE COAST WILL BE FAR ENOUGH TO OUR SE TO MINIMIZE ANY IMPACT ON CENTRAL NC. THE WEAK LOW LEVEL FLOW PATTERN HOLDS WITH A WEAK HIGH PRESSURE RIDGE SPANNING THE AREA AND A VERY WEAK SURFACE LOW/INVERTED TROUGH OVER PA/WV/VA... A REFLECTION OF THE CLIPPER MID LEVEL VORTEX NOW OVER ERN MI THAT IS EXPECTED TO CROSS THE MIDATLANTIC REGION REGION LATE TONIGHT THROUGH WED MORNING. MODELS VARY IN THEIR IMPACTS ON OUR WEATHER WITH THIS FEATURE... WITH THE NAM MUCH MORE BULLISH THAN THE GFS IN TAKING A SLUG OF 850-700 MB MOISTURE EAST ACROSS THE AREA TONIGHT. THIS SEEMS A BIT OVERDONE BUT IT IS SOMEWHAT SUPPORTED BY OBSERVED SOUNDINGS UPSTREAM... SO WILL RETAIN A FEW CLOUDS OVER THE AREA OVERNIGHT... AND LATER FORECASTS CAN INCREASE THIS COVERAGE IF LATER GUIDANCE SUPPORTS THE NAM. LOWS 57-60. -GIH && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 245 AM TUESDAY... AS NOTED ABOVE... WE SHOULD SEE AT LEAST SOME SCATTERED CLOUDS MAINLY OVER THE EAST WED MORNING. THE PRESENCE OR LACK OF SUCH CLOUDS WILL IMPACT HOW MUCH FOG FORMS WED MORNING. WE SHOULD SEE AT LEAST SOME LIGHT FOG TO START THE DAY... AND PERHAPS MORE DENSE IF THE AFOREMENTIONED CLIPPER-ASSOCIATED CLOUDS DO NOT HAPPEN. OTHERWISE... EXPECT A PARTLY TO MOSTLY SUNNY DAY. THE CLIPPER LOW WILL CROSS NEW ENGLAND AS THE STRONG VORTICITY MAX ROUNDS ITS BASE... SHIFTING OFF THE NJ COAST... AND WE SHOULD SEE A BIT MORE FLAT DAYTIME CUMULUS FROM THE TRIANGLE NORTH AND EAST CLOSER TO THE LOW. MODELS SHOW WEAK MID LEVEL RIDGING PUSHING IN FROM THE WEST LATE... BETWEEN THE DEPARTING CLIPPER AND A DEEPENING TROUGH COVERING THE EASTERN ROCKIES AND HIGH PLAINS LATE WED/WED NIGHT. WHILE MODELS SHOW A MINOR PERTURBATION TRACKING EASTWARD OVER THE SOUTHEAST STATES WED NIGHT... THIS SHOULD BE OF LITTLE CONSEQUENCE WITH DEEP DRY AIR MOVING IN. EXPECT DRY WEATHER THROUGH WED NIGHT. THICKNESSES ARE EXPECTED TO START WED ABOUT 10 M ABOVE NORMAL... SUPPORTING HIGHS ABOUT A CATEGORY ABOVE NORMAL... 80-84. SOME CLOUDINESS POSSIBLE WED NIGHT ESPECIALLY OVER THE WEST WHERE MODELS INDICATE AN UPTICK IN LOW LEVEL MOISTURE TRANSPORT GENERATED BY LIGHT BUT CONFLUENT AND UPSLOPE-DIRECTED LOW LEVEL FLOW. LOWS WITHIN A COUPLE DEGREES OF 60. -GIH && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... FOR THE PERIOD THURSDAY THROUGH THURSDAY NIGHT...A MID-LEVEL RIDGE AXIS BUILDS INTO CENTRAL NORTH CAROLINA THURSDAY...WITH THE AXIS MOVING EAST THURSDAY NIGHT. THE GUIDANCE HAS CONTINUED TO FORECAST VERY MINOR QPF IN CENTRAL NORTH CAROLINA DURING THIS PERIOD...WITH THE GFS FORECASTING THIS THURSDAY AND THE NAM MORE THURSDAY NIGHT. THE GFS DOES HAVE A RELATIVE MAXIMUM OF 850MB THETA-E AIR OVER CENTRAL NORTH CAROLINA THURSDAY WITH WEAK 850MB LIFT...BUT HEIGHTS ALOFT ARE RISING AND ANY LOW-LEVEL FORCING WITH ANY SURFACE BOUNDARY SHOULD BE WEAK. LIFTED INDICES ARE ABOVE 0C...AND MLCAPE IN THE LOWEST KM DOES NOT REGISTER AS BUFR SOUNDINGS FROM BOTH THE NAM AND GFS APPEAR CAPPED. GIVEN THE ORIENTATION OF 1000-500MB THICKNESSES...POSSIBLY A SHOWER COULD DRIFT SOUTHEAST FOLLOWING THE THERMAL WIND FROM HIGHER TERRAIN AND GET CLOSE TO THE NORTHWEST PIEDMONT THURSDAY AFTERNOON OR EVENING...BUT GIVEN THE UNCERTAINTY WILL KEEP THE FORECAST DRY. MOS GUIDANCE POPS ARE IN SINGLE FIGURES IN BOTH THE MAV AND THE MET. WITH AT LEAST A PARTLY SUNNY SKY EXPECTED...1000-850MB THICKNESSES WOULD SUGGEST LOWER TO MID 80S FOR HIGHS...IN CONJUNCTION WITH MAV AND MET MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT NEAR 60 IN THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN UNDERNEATH THE RIDGE AXIS ALOFT FOR A GOOD PART OF THE NIGHT...LOWER 60S ELSEWHERE AND POSSIBLY ON THE HIGHER END OF THE LOWER 60S TOWARD THE TRIAD AS THE WINDS OFF OF THE SURFACE START TO INCREASE OVERNIGHT. FOR THE PERIOD FRIDAY THROUGH TUESDAY...THE ECMWF AND THE GFS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF AN ELONGATED MID-LEVEL SHORTWAVE MOVING INTO CENTRAL NORTH CAROLINA BY 00Z SATURDAY AND THEN EAST OF THE AREA BY 12Z SATURDAY. ONE TREND HAS BEEN FOR THE MID-LEVEL RIDGE TO BE SLIGHTLY MORE AMPLIFIED... WHICH...IF THE TREND CONTINUES...COULD SLOW THE ONSET OF ANY SHOWERS OR THUNDERSTORMS DURING THE DAY FRIDAY. LAPSE RATES ON COARSE GFS AND ECMWF MODEL SOUNDINGS ARE NEAR MOIST ADIABATIC AT BEST...SO INSTABILITY SHOULD BE LIMITED. STILL...WITH WINDS OFF OF THE SURFACE INCREASING TO AT OR A LITTLE ABOVE 30KT AHEAD OF THE COLD FRONT... CURRENT THINKING IS THAT ANY STRONGER STORM COULD HAVE A GUSTY WIND...THOUGH NOT CONFIDENT CURENTLY IN THE PROBABILITY OF ISOLATED SEVERE WEATHER GIVEN THE MARGINAL LAPSE RATES. DRY CONDITIONS WILL BE FORECAST SATURDAY THROUGH SUNDAY...THOUGH THE ECMWF DOES CONTINUE TO FORECAST GREATER DIGGING WITH UPPER-LEVEL LOW PRESSURE MOVING THROUGH THE OHIO VALLEY AND EAST ACROSS AREAS JUST NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT. AGAIN...THE TREND OF THIS WILL NEED TO BE WATCHED...BUT CURRENTLY THE MID-LEVEL MOISTURE ASSOCIATED WITH THE UPPER LOW ON THE ECMWF STAYS NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT INTO EARLY SUNDAY. BEHIND THE COLD FRONT ON SATURDAY OR SATURDAY NIGHT...HOWEVER...SOME JET STREAK CIRRUS COULD OCCUR IF THE GFS AND ECMWF UPPER-LEVEL MOISTURE FORECASTS VERIFY IN CONJUNCTION WITH THE JET AXIS ALOFT. THE ECMWF IS ALSO MORE AMPLIFIED WITH ANOTHER IN A SERIES OF MID- LEVEL WAVES IN THE NORTHWEST FLOW...THIS ONE APPROACHING THE SOUTHERN APPALACHIANS MONDAY. THE GFS IS DRY WITH LITTLE FORCING... WHILE THE ECMWF HAS MORE OF A SURFACE REFLECTION WITH THE MID-LEVEL WAVE AND ENOUGH MID-LEVEL MOISTURE FOR LIGHT PRECIPITATION OVER THE WESTERN AND NORTHWEST PIEDMONT LATE MONDAY AFTERNOON OR MONDAY NIGHT. WITH SURFACE HIGH PRESSURE OVER THE GULF...IF THERE IS ANY PRECIPITATION MONDAY...THE THOUGHT IS IT WOULD BE MID-LEVEL DRIVEN AND MOSTLY LIGHT. FOR THIS FORECAST WILL TREND A LITTLE MORE PESSIMISTIC ON THE LAST DAY OF THE LONG-TERM PERIOD...INCREASING CLOUDS BUT KEEPING THE OVERALL FORECAST DRY. AFTER HIGHS IN THE MID 70S TO NEAR 80 FRIDAY AHEAD OF THE FRONT... BY SATURDAY NIGHT...AS THE GUIDANCE STILL SHOWS CHILLY 1000-850MB THICKNESSES INTO THE 1340S...THERE SHOULD BE AT LEAST A FEW 40S OVER THE WESTERN AND NORTHERN PIEDMONT. MODEST WARMING FOR THE END OF THE WEEKEND AND THE START OF NEXT WEEK. HIGHS SHOULD BE BACK AT LEAST IN THE LOWER TO MID 70S FOR MONDAY. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... AS OF 640 AM TUESDAY... ADVERSE AVIATION CONDITIONS ARE LIKELY TO HOLD OVER CENTRAL NC THROUGH 14Z OR 15Z THIS MORNING... WITH IMPROVEMENT TO VFR TO FOLLOW BY LATE MORNING... WHICH WILL HOLD THROUGH 04Z (MIDNIGHT TONIGHT). THE MID LEVEL TROUGH AXIS OVER THE ERN CAROLINAS WILL CONTINUE TO SHIFT EAST AND OFFSHORE THIS MORNING. THE RESULTANT CLEARING SKIES AND LIGHT WINDS HAVE LED TO LOW STRATUS/FOG DEVELOPMENT THIS MORNING. THESE IFR/LIFR CONDITIONS HAVE BEEN DISCONTINUOUS... WITH AVIATION CONDITIONS PERIODICALLY SWINGING WILDLY BETWEEN LIFR AND MVFR... MAKING THE TAFS CHALLENGING THIS MORNING. PILOTS SHOULD BE PARTICULARLY ALERT FOR POSSIBLE VFR HOLES WITHIN IFR/LIFR CONDITIONS THROUGH MID MORNING. OTHERWISE... ANY CIGS SHOULD LIFT AND BEGIN TO BREAK UP BY 15Z OR 16Z... WITH VFR CONDITIONS THEN PREVAILING THROUGH THE AFTERNOON AND EVENING HOURS. AFTER MIDNIGHT... WE EXPECT REDEVELOPMENT OF SHALLOW IFR OR LIFR FOG LATE IN THE TAF VALID PERIOD... WITH THE WORST CONDITIONS EXPECTED BETWEEN 08Z AND 12Z. SURFACE WINDS WILL REMAIN LIGHT/VARIABLE (MAINLY FROM THE NORTHWEST) MOSTLY UNDER 5 KTS TODAY/TONIGHT. LOOKING BEYOND 12Z WED MORNING... SUB-VFR FOG EARLY WED MORNING SHOULD MIX OUT BY 15Z. OTHERWISE... VFR CONDITIONS WILL PREVAIL THROUGH FRI... ALTHOUGH SHALLOW IFR GROUND FOG IS AGAIN POSSIBLE AREAWIDE 08Z-13Z EACH MORNING THU AND FRI. A STRONG FRONTAL SYSTEM WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN WIDESPREAD SHOWERS/STORMS FRI AFTERNOON INTO FRI NIGHT. HIGH PRESSURE WILL THEN BUILD IN YIELDING VFR CONDITIONS SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>011-021>028-038>043-073>077-083>086-088. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...DJF AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
636 AM EDT TUE SEP 30 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE FARTHER OFFSHORE TODAY AS HIGH PRESSURE BUILDS IN BEHIND IT. WEAK HIGH PRESSURE WILL REMAIN OVER THE CAROLINAS THROUGH EARLY FRIDAY. A STRONG COLD FRONT WILL MOVE ACROSS THE REGION LATE FRIDAY INTO EARLY SATURDAY ACCOMPANIED BY A CHANCE FOR SHOWERS AND THUNDERSTORMS. COOL AND DRY HIGH PRESSURE WILL FOLLOW THIS FRONT FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...PRECIPITATION IS OFF THE COAST WITH LOW PRESSURE OFF THE SC COAST. 11-3.9U SATELLITE IMAGERY SHOWS AREAS OF STRATUS ACROSS THE FORECAST AREA WHILE SURFACE OBS SHOW A LARGE RANGE IN VISIBILITIES. PATCHY FOG AND SCT-V-BKN STRATUS WILL PERSIST FOR A COUPLE HOURS AFTER SUNRISE. NO MAJOR CHANGES TO THE CURRENT FORECAST. PREVIOUS DISCUSSION... THE LAST OF THE -RA/DZ IS EXITING THE COAST WITH CLEARING SKIES FROM WEST TO EAST. POCKETS OF STRATO-CUMULUS WILL PERSIST A WHILE LONGER...WHILE STRATUS IS LIKELY TO DEVELOP THROUGH THE EARLY MORNING. STRATUS AND FOG ARE A BETTER BET FARTHER INLAND...ESPECIALLY ACROSS THOSE AREAS WHERE SKIES ALREADY CLEARED AND VERY LIGHT WINDS. ANY STRATUS/FOG WILL DISSIPATE DURING THE MORNING AS DRIER AIR ALOFT MIXES INTO THE LOWER COLUMN RESULTING IN A MOSTLY SUNNY AFTERNOON. HIGH TEMPERATURES WILL BE AROUND 80F MOST LOCATIONS THIS AFTERNOON WITH LOWS AROUND 60 INLAND...TO THE LOWER 60S AT THE COAST. EXPECT STRATUS/FOG TO DEVELOP INLAND AGAIN TONIGHT. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...HIGH PRESSURE WILL EXTEND DOWN FROM THE NORTH INTO THE CAROLINAS REMAINING FAIRLY WEAK WED THROUGH THURS. AT THE SAME TIME A FLAT UPPER LEVEL FLOW WILL SHARPEN AS RIDGE BUILDS UP THROUGH THE SOUTHEAST. OVERALL SHOULD SEE PLENTY OF DRY AIR AND SUBSIDENCE ALOFT THROUGH MID WEEK. LIGHT NORTHERLY FLOW WILL SHIFT AROUND BECOMING MORE E-SE AND LIGHTENING UP AS HIGH SHIFTS EAST THROUGH TIME. PCP WATER VALUES DOWN LESS THAN AN INCH MAY INCREASE SLIGHTLY DUE TO A LITTLE IMPULSE MOVING THROUGH IN THE UPPER LEVELS LATER ON WED AND SOME CU DEVELOPMENT IN LOCALIZED CONVERGENCE BOTH AFTERNOONS. OTHERWISE EXPECT PLENTY OF SUNSHINE AND WARM TEMPS AS RIDGE BUILDS AND HEIGHTS RISE ALONG WITH EARLY FALL SUNSHINE. HIGHS SHOULD REACH THE MID 80S ACROSS THE SC PEE DEE REGION...LOWER 80S ELSEWHERE EXCEPT A LITTLE COOLER AT THE BEACHES WHERE WATER TEMPERATURES HAVE BEGUN THEIR SEASONAL DROP...NOW IN THE MID-UPPER 70S. LOWS SHOULD FALL INTO THE LOWER 60S WITH MID- UPPER 60S AT THE BEACHES. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 AM TUESDAY...RETURN FLOW WILL DEVELOP THROUGH FRI AS HIGH PRESSURE SHIFTS OFF THE COAST. THIS INCREASING SOUTHERLY FLOW WILL BRING MOISTURE BACK INTO THE CAROLINAS WITH INCREASING CLOUDS AND POTENTIAL FOR SHWRS THROUGH THE DAY. PCP WATER VALUES AS LOW AS AN INCH FRI MORNING WILL BE ON THE RISE WITH VALUES UP TO 2 INCHES BY AFTN OVER INLAND AREAS AS LLJ UP TO 30 KTS PROVIDES A DECENT FEED OF MOISTURE AHEAD OF APPROACHING COLD FRONT. EXPECT MORE WIDESPREAD SHWRS/TSTMS INLAND BY AFTN AND REACHING THE COAST BY EVENING AS MID TO UPPER TROUGH DIGS DOWN FROM THE GREAT LAKES PUSHING FRONT EAST THROUGH SATURDAY. THE TROUGH DOES BECOME SLIGHTLY NEGATIVE TILTED THROUGH SATURDAY WITH SOME UPPER LEVEL DYNAMICS REACHING SOUTH INTO THE CAROLINAS. THIS MAY DELAY THE CLEARING ON SATURDAY BUT OVERALL EXPECT A DEEP DRY W-NW FLOW TO PRODUCE SOME EXCEPTIONAL FALL LIKE WEATHER FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. DEWPOINT TEMPS MAY END UP BELOW 50 DEGREES BY SUNDAY. THIS DRY AIR WILL ALLOW LARGE DIURNAL SWINGS IN TEMPS WITH COOL START TO THE MORNINGS SUN AND MON AND TEMPS REACHING INTO THE MID 70S MOST PLACES FOR AFTN HIGHS WITH BRIGHT SUNSHINE. PCP WATER VALUES WILL PLUMMET TO A HALF INCH OR LESS BY SUNDAY MORNING. OVERNIGHT LOWS WILL BE DOWN IN THE 50S SUN AND MON. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...THE -RA FROM EARLIER TONIGHT HAS MOSTLY PUSHED OFFSHORE...AND THE MID LEVEL CLOUDS SHOULD GRADUALLY THIN OVERNIGHT AS THE UPPER TROUGH MOVES OVERHEAD AND OFF THE COAST. SURFACE OBS INDICATE FOG IS DEVELOPING OVER THE CENTRAL CAROLINAS WHERE THE WINDS HAVE GONE CALM AND THE MID LEVEL CIGS ARE NO MORE. THEREFORE...HAVE ADDED TEMPO IFR VSBYS FOR KLBT/KFLO EARLY THIS MORNING. THIS TREND FOLLOWS SOME OF THE LATEST HRRR RUNS SHOWING FOG/STRATUS EXPANDING INLAND AFTER 09Z. STILL THINK THE DEVELOPING LOW OFF THE SOUTHEAST COAST WILL KEEP WINDS AT THE COASTAL TERMINALS STRONG ENOUGH TO PREVENT ANY FOG...BUT SOME TEMPO IFR CIGS CANNOT BE RULED OUT BY DAYBREAK. WILL KEEP SCT 500 FT STRATUS AT THE COAST ATTM. DURING THE DAY... DRIER AIR BEHIND THE UPPER TROUGH WILL ALLOW VFR CONDITIONS TO DEVELOP AND PERSIST FOR THE REST OF THE TAF PERIOD. EXPECT NORTHEAST WINDS AOB 10 KT DURING THE DAY...BECOMING LIGHT/VRB AFTER 00Z WED. EXTENDED OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH FRI. CHANCE OF SHOWERS/MVFR LATE FRI/EARLY SAT WITH A STRONG COLD FRONT. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM TUESDAY...NORTHERLY FLOW ACROSS THE COASTAL WATERS THIS MORNING WITH LOW PRESSURE OFF THE SC COAST. THE LOW WILL CONTINUE TO PULL AWAY FROM THE CAROLINA COAST THROUGH THE DAY. WINDS ARE LIKELY AROUND 15 KNOTS WITH GUSTS TO AROUND 20 KNOTS AWAY FROM THE COAST...AND AROUND 10 KNOTS NEAR THE COAST. SEAS ARE LIKELY 3-5 FT AWAY FROM THE COAST TO 2 FT NEAR SHORE. PREVIOUS FORECAST...NORTHERLY FLOW WILL PREVAIL WITH LOW PRESSURE POSITIONED SOUTH...THEN EAST-SOUTHEAST...OF THE WATERS TODAY THROUGH TONIGHT. THE PRESSURE GRADIENT WILL BE MORE OF A FACTOR ACROSS THE OUTER COASTAL WATERS WITH SPEEDS AROUND 15 KNOTS THIS MORNING AND FIRST PART OF THE AFTERNOON. WINDS WILL DIMINISH ACROSS ALL WATERS BY 00Z WED WITH NORTHERLY WINDS AROUND 10 KNOTS FOR THE OVERNIGHT. SEAS WILL BE LOWEST ACROSS THE NEAR SHORE BRUNSWICK WATERS WHERE THE FLOW WILL BE OFFSHORE. LIKEWISE...EXPECT SEAS TO BE HIGHER IN THE VICINITY OF THE OUTER FRYING PAN SHOALS WATERS WITH SHORTER PERIOD SEAS IN THE 3-5 FT RANGE. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...WEAK HIGH PRESSURE WILL EXTEND DOWN INTO THE COASTAL WATERS FROM THE NORTH. EXPECT WINDS TO REMAIN FAIRLY LIGHT IN A RELAXED GRADIENT..STARTING OUT FROM THE NORTHEAST AND VEERING AROUND BECOMING MORE ON SHORE AND EVENTUALLY SE BY FRI MORNING AS THE HIGH MIGRATES EASTWARD WITH TIME. NEAR SHORE WINDS WILL BE INFLUENCED BY THE SEA BREEZE CAUSING A SLIGHT SPIKE IN WINDS IN THE AFTERNOONS. SEAS WILL BASICALLY BE 3 FT OR LESS...SUBSIDING A BIT FROM WED TO THURS. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 330 AM TUESDAY...LIGHT SOUTHEAST WINDS WILL START THE DAY ON FRIDAY AS HIGH PRESSURE SHIFTS FARTHER OFF SHORE. AN INCREASING RETURN FLOW WILL DEVELOP THROUGH THE DAY AS A COLD FRONT APPROACHES FROM THE NORTHWEST. EXPECT SE WINDS TO INCREASE UP TO 15 TO 20 KTS OUT OF THE SOUTH BY FRI EVE. THIS WILL KICK SEAS UP FROM AROUND 2 FT EARLY FRI TO 3 TO 5 FT BY SAT MORNING. MAY RUN INTO A FEW HOURS OF SCA CONDITIONS IN STRONGEST ON SHORE PUSH RIGHT AHEAD OF THE FRONT FRI NIGHT. ONCE THE COLD FRONT MOVES THROUGH THE WATERS SATURDAY MORNING THE WINDS WILL VEER AROUND TO THE NW REMAINING UP TO 15 KTS INITIALLY BUT LIGHTENING UP THROUGH THE WEEKEND. THE OFF SHORE FLOW WILL KEEP HIGHER SEAS WELL OFF SHORE BY LATE SATURDAY. THEREFORE EXPECT LOCAL WATERS DOWN TO 2 TO 4 FT BY SAT EVENING. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...SRP SHORT TERM...RGZ LONG TERM...RGZ AVIATION...BJR/SRP
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
350 AM EDT TUE SEP 30 2014 .SYNOPSIS... LOW PRESSURE WILL MOVE FARTHER OFF SHORE TODAY AS HIGH PRESSURE BUILDS IN BEHIND IT. WEAK HIGH PRESSURE WILL REMAIN OVER THE CAROLINAS THROUGH EARLY FRIDAY. A STRONG COLD FRONT WILL MOVE ACROSS THE REGION LATE FRIDAY INTO EARLY SATURDAY ACCOMPANIED BY A CHANCE FOR SHOWERS AND THUNDERSTORMS. COOL AND DRY HIGH PRESSURE WILL FOLLOW THIS FRONT FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY...THE LAST OF THE -RA/DZ IS EXITING THE COAST WITH CLEARING SKIES FROM WEST TO EAST. POCKETS OF STRATO-CUMULUS WILL PERSIST A WHILE LONGER...WHILE STRATUS IS LIKELY TO DEVELOP THROUGH THE EARLY MORNING. STRATUS AND FOG ARE A BETTER BET FARTHER INLAND...ESPECIALLY ACROSS THOSE AREAS WHERE SKIES ALREADY CLEARED AND VERY LIGHT WINDS. ANY STRATUS/FOG WILL DISSIPATE DURING THE MORNING AS DRIER AIR ALOFT MIXES INTO THE LOWER COLUMN RESULTING IN A MOSTLY SUNNY AFTERNOON. HIGH TEMPERATURES WILL BE AROUND 80F MOST LOCATIONS THIS AFTERNOON WITH LOWS AROUND 60 INLAND...TO THE LOWER 60S AT THE COAST. EXPECT STRATUS/FOG TO DEVELOP INLAND AGAIN TONIGHT. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...HIGH PRESSURE WILL EXTEND DOWN FROM THE NORTH INTO THE CAROLINAS REMAINING FAIRLY WEAK WED THROUGH THURS. AT THE SAME TIME A FLAT UPPER LEVEL FLOW WILL SHARPEN AS RIDGE BUILDS UP THROUGH THE SOUTHEAST. OVERALL SHOULD SEE PLENTY OF DRY AIR AND SUBSIDENCE ALOFT THROUGH MID WEEK. LIGHT NORTHERLY FLOW WILL SHIFT AROUND BECOMING MORE E-SE AND LIGHTENING UP AS HIGH SHIFTS EAST THROUGH TIME. PCP WATER VALUES DOWN LESS THAN AN INCH MAY INCREASE SLIGHTLY DUE TO A LITTLE IMPULSE MOVING THROUGH IN THE UPPER LEVELS LATER ON WED AND SOME CU DEVELOPMENT IN LOCALIZED CONVERGENCE BOTH AFTERNOONS. OTHERWISE EXPECT PLENTY OF SUNSHINE AND WARM TEMPS AS RIDGE BUILDS AND HEIGHTS RISE ALONG WITH EARLY FALL SUNSHINE. HIGHS SHOULD REACH THE MID 80S ACROSS THE SC PEE DEE REGION...LOWER 80S ELSEWHERE EXCEPT A LITTLE COOLER AT THE BEACHES WHERE WATER TEMPERATURES HAVE BEGUN THEIR SEASONAL DROP...NOW IN THE MID-UPPER 70S. LOWS SHOULD FALL INTO THE LOWER 60S WITH MID- UPPER 60S AT THE BEACHES. && .LONG TERM /FRIDAY THROUGH MONDAY/... AS OF 330 AM TUESDAY...RETURN FLOW WILL DEVELOP THROUGH FRI AS HIGH PRESSURE SHIFTS OFF THE COAST. THIS INCREASING SOUTHERLY FLOW WILL BRING MOISTURE BACK INTO THE CAROLINAS WITH INCREASING CLOUDS AND POTENTIAL FOR SHWRS THROUGH THE DAY. PCP WATER VALUES AS LOW AS AN INCH FRI MORNING WILL BE ON THE RISE WITH VALUES UP TO 2 INCHES BY AFTN OVER INLAND AREAS AS LLJ UP TO 30 KTS PROVIDES A DECENT FEED OF MOISTURE AHEAD OF APPROACHING COLD FRONT. EXPECT MORE WIDESPREAD SHWRS/TSTMS INLAND BY AFTN AND REACHING THE COAST BY EVENING AS MID TO UPPER TROUGH DIGS DOWN FROM THE GREAT LAKES PUSHING FRONT EAST THROUGH SATURDAY. THE TROUGH DOES BECOME SLIGHTLY NEGATIVE TILTED THROUGH SATURDAY WITH SOME UPPER LEVEL DYNAMICS REACHING SOUTH INTO THE CAROLINAS. THIS MAY DELAY THE CLEARING ON SATURDAY BUT OVERALL EXPECT A DEEP DRY W-NW FLOW TO PRODUCE SOME EXCEPTIONAL FALL LIKE WEATHER FOR THE LATTER HALF OF THE WEEKEND INTO EARLY NEXT WEEK. DEWPOINT TEMPS MAY END UP BELOW 50 DEGREES BY SUNDAY. THIS DRY AIR WILL ALLOW LARGE DIURNAL SWINGS IN TEMPS WITH COOL START TO THE MORNINGS SUN AND MON AND TEMPS REACHING INTO THE MID 70S MOST PLACES FOR AFTN HIGHS WITH BRIGHT SUNSHINE. PCP WATER VALUES WILL PLUMMET TO A HALF INCH OR LESS BY SUNDAY MORNING. OVERNIGHT LOWS WILL BE DOWN IN THE 50S SUN AND MON. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 06Z...THE -RA FROM EARLIER TONIGHT HAS MOSTLY PUSHED OFFSHORE...AND THE MID LEVEL CLOUDS SHOULD GRADUALLY THIN OVERNIGHT AS THE UPPER TROUGH MOVES OVERHEAD AND OFF THE COAST. SURFACE OBS INDICATE FOG IS DEVELOPING OVER THE CENTRAL CAROLINAS WHERE THE WINDS HAVE GONE CALM AND THE MID LEVEL CIGS ARE NO MORE. THEREFORE...HAVE ADDED TEMPO IFR VSBYS FOR KLBT/KFLO EARLY THIS MORNING. THIS TREND FOLLOWS SOME OF THE LATEST HRRR RUNS SHOWING FOG/STRATUS EXPANDING INLAND AFTER 09Z. STILL THINK THE DEVELOPING LOW OFF THE SOUTHEAST COAST WILL KEEP WINDS AT THE COASTAL TERMINALS STRONG ENOUGH TO PREVENT ANY FOG...BUT SOME TEMPO IFR CIGS CANNOT BE RULED OUT BY DAYBREAK. WILL KEEP SCT 500 FT STRATUS AT THE COAST ATTM. DURING THE DAY... DRIER AIR BEHIND THE UPPER TROUGH WILL ALLOW VFR CONDITIONS TO DEVELOP AND PERSIST FOR THE REST OF THE TAF PERIOD. EXPECT NORTHEAST WINDS AOB 10 KT DURING THE DAY...BECOMING LIGHT/VRB AFTER 00Z WED. EXTENDED OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH FRI. CHANCE OF SHOWERS/MVFR LATE FRI/EARLY SAT WITH A STRONG COLD FRONT. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY...NORTHERLY FLOW WILL PREVAIL WITH LOW PRESSURE POSITIONED SOUTH...THEN EAST-SOUTHEAST...OF THE WATERS TODAY THROUGH TONIGHT. THE PRESSURE GRADIENT WILL BE MORE OF A FACTOR ACROSS THE OUTER COASTAL WATERS WITH SPEEDS AROUND 15 KNOTS THIS MORNING AND FIRST PART OF THE AFTERNOON. WINDS WILL DIMINISH ACROSS ALL WATERS BY 00Z WED WITH NORTHERLY WINDS AROUND 10 KNOTS FOR THE OVERNIGHT. SEAS WILL BE LOWEST ACROSS THE NEAR SHORE BRUNSWICK WATERS WHERE THE FLOW WILL BE OFFSHORE. LIKEWISE...EXPECT SEAS TO BE HIGHER IN THE VICINITY OF THE OUTER FRYING PAN SHOALS WATERS WITH SHORTER PERIOD SEAS IN THE 3-5 FT RANGE. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 330 AM TUESDAY...WEAK HIGH PRESSURE WILL EXTEND DOWN INTO THE COASTAL WATERS FROM THE NORTH. EXPECT WINDS TO REMAIN FAIRLY LIGHT IN A RELAXED GRADIENT..STARTING OUT FROM THE NORTHEAST AND VEERING AROUND BECOMING MORE ON SHORE AND EVENTUALLY SE BY FRI MORNING AS THE HIGH MIGRATES EASTWARD WITH TIME. NEAR SHORE WINDS WILL BE INFLUENCED BY THE SEA BREEZE CAUSING A SLIGHT SPIKE IN WINDS IN THE AFTERNOONS. SEAS WILL BASICALLY BE 3 FT OR LESS...SUBSIDING A BIT FROM WED TO THURS. LONG TERM /FRIDAY THROUGH SATURDAY/... AS OF 330 AM TUESDAY...LIGHT SOUTHEAST WINDS WILL START THE DAY ON FRIDAY AS HIGH PRESSURE SHIFTS FARTHER OFF SHORE. AN INCREASING RETURN FLOW WILL DEVELOP THROUGH THE DAY AS A COLD FRONT APPROACHES FROM THE NORTHWEST. EXPECT SE WINDS TO INCREASE UP TO 15 TO 20 KTS OUT OF THE SOUTH BY FRI EVE. THIS WILL KICK SEAS UP FROM AROUND 2 FT EARLY FRI TO 3 TO 5 FT BY SAT MORNING. MAY RUN INTO A FEW HOURS OF SCA CONDITIONS IN STRONGEST ON SHORE PUSH RIGHT AHEAD OF THE FRONT FRI NIGHT. ONCE THE COLD FRONT MOVES THROUGH THE WATERS SATURDAY MORNING THE WINDS WILL VEER AROUND TO THE NW REMAINING UP TO 15 KTS INITIALLY BUT LIGHTENING UP THROUGH THE WEEKEND. THE OFF SHORE FLOW WILL KEEP HIGHER SEAS WELL OFF SHORE BY LATE SATURDAY. THEREFORE EXPECT LOCAL WATERS DOWN TO 2 TO 4 FT BY SAT EVENING. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...SRP SHORT TERM...RGZ LONG TERM...RGZ AVIATION...BJR/SRP
AREA FORECAST DISCUSSION
NWS RALEIGH NC
330 AM EDT TUE SEP 30 2014 .SYNOPSIS...WEAK LOW PRESSURE OVER NORTHEAST FLORIDA WILL TRACK NORTHEASTWARD OFF THE SOUTHEAST COAST TODAY. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. A STRONG STORM SYSTEM WILL APPROACH FROM THE WEST ON FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM TUESDAY... UPDATE: FOG HAS BECOME QUITE DENSE OVER MOST OF CENTRAL NC (WITH THE EXCEPTION OF THE FAR SOUTHEAST SECTIONS)... WARRANTING ISSUANCE OF A DENSE FOG ADVISORY UNTIL 10 AM. VSBYS SHOULD GRADUALLY IMPROVE DURING THE 9AM-11AM TIME FRAME. EARLIER DISCUSSION FROM 222 AM TUESDAY... TODAY... FIRST CONCERN EARLY THIS MORNING IS THE DEGREE OF FOG DEVELOPMENT OVER THE AREA THUS FAR. THE MID LEVEL SHORTWAVE TROUGH IS NOW HEADING EAST OFF THE CAROLINA COAST... WITH THE VEIL OF MID/HIGH CLOUDS DEPARTING ALONG WITH IT. THE DAMP GROUND COMBINED WITH THE CLEARING SKIES AND LIGHT/CALM WINDS SHOULD CONTINUE TO FOSTER DEVELOPMENT OF LOW CLOUDS AND FOG EARLY THIS MORNING... ALTHOUGH THE CURRENT PATCHY/FLEETING NATURE OF THESE CONDITIONS (SEVERAL SITES HAVE BOUNCED AROUND BETWEEN 1/4 MI AND 5 MI IN FOG THE LAST FEW HRS) GIVES US PAUSE AS TO THE NEED FOR A DENSE FOG ADVISORY. THE HRRR DEPICTS A FAIRLY SOLID DECK OF LOW CLOUDS/FOG FORMING OVER THE NEXT FEW HOURS HOWEVER. WILL CONTINUE TO MONITOR THE OBSERVED TRENDS. IF VSBYS DO DROP AND HOLD THERE FOR OVER AN HOUR... THEY`RE LIKELY TO HOLD FIRM THROUGH MID MORNING... GIVEN THE WEAK WIND FIELD THROUGH THE LOWEST FEW THOUSAND FEET RESULTING IN MINIMAL STIRRING/DISPERSION HORIZONTALLY OR VERTICALLY. WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY THROUGH MID MORNING TO ACCOUNT FOR THIS. THEN... ONCE HEATING AND SUBSEQUENT MIXING HELPS TO DISPERSE THE FOG/STRATUS... EXPECT A GOOD BIT OF SUNSHINE THROUGH THE DAY... WITH FLAT AFTERNOON STRATOCU LIKELY TO STAY SCATTERED AT WORST. WITH THICKNESSES CLOSE TO SEASONAL NORMALS... STILL LOOK FOR HIGHS WITHIN A FEW DEGREES OF 80. FOR TONIGHT: THE SURFACE LOW TRACKING TOWARD THE NE WELL OFF THE SE COAST WILL BE FAR ENOUGH TO OUR SE TO MINIMIZE ANY IMPACT ON CENTRAL NC. THE WEAK LOW LEVEL FLOW PATTERN HOLDS WITH A WEAK HIGH PRESSURE RIDGE SPANNING THE AREA AND A VERY WEAK SURFACE LOW/INVERTED TROUGH OVER PA/WV/VA... A REFLECTION OF THE CLIPPER MID LEVEL VORTEX NOW OVER ERN MI THAT IS EXPECTED TO CROSS THE MIDATLANTIC REGION REGION LATE TONIGHT THROUGH WED MORNING. MODELS VARY IN THEIR IMPACTS ON OUR WEATHER WITH THIS FEATURE... WITH THE NAM MUCH MORE BULLISH THAN THE GFS IN TAKING A SLUG OF 850-700 MB MOISTURE EAST ACROSS THE AREA TONIGHT. THIS SEEMS A BIT OVERDONE BUT IT IS SOMEWHAT SUPPORTED BY OBSERVED SOUNDINGS UPSTREAM... SO WILL RETAIN A FEW CLOUDS OVER THE AREA OVERNIGHT... AND LATER FORECASTS CAN INCREASE THIS COVERAGE IF LATER GUIDANCE SUPPORTS THE NAM. LOWS 57-60. -GIH && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 245 AM TUESDAY... AS NOTED ABOVE... WE SHOULD SEE AT LEAST SOME SCATTERED CLOUDS MAINLY OVER THE EAST WED MORNING. THE PRESENCE OR LACK OF SUCH CLOUDS WILL IMPACT HOW MUCH FOG FORMS WED MORNING. WE SHOULD SEE AT LEAST SOME LIGHT FOG TO START THE DAY... AND PERHAPS MORE DENSE IF THE AFOREMENTIONED CLIPPER-ASSOCIATED CLOUDS DO NOT HAPPEN. OTHERWISE... EXPECT A PARTLY TO MOSTLY SUNNY DAY. THE CLIPPER LOW WILL CROSS NEW ENGLAND AS THE STRONG VORTICITY MAX ROUNDS ITS BASE... SHIFTING OFF THE NJ COAST... AND WE SHOULD SEE A BIT MORE FLAT DAYTIME CUMULUS FROM THE TRIANGLE NORTH AND EAST CLOSER TO THE LOW. MODELS SHOW WEAK MID LEVEL RIDGING PUSHING IN FROM THE WEST LATE... BETWEEN THE DEPARTING CLIPPER AND A DEEPENING TROUGH COVERING THE EASTERN ROCKIES AND HIGH PLAINS LATE WED/WED NIGHT. WHILE MODELS SHOW A MINOR PERTURBATION TRACKING EASTWARD OVER THE SOUTHEAST STATES WED NIGHT... THIS SHOULD BE OF LITTLE CONSEQUENCE WITH DEEP DRY AIR MOVING IN. EXPECT DRY WEATHER THROUGH WED NIGHT. THICKNESSES ARE EXPECTED TO START WED ABOUT 10 M ABOVE NORMAL... SUPPORTING HIGHS ABOUT A CATEGORY ABOVE NORMAL... 80-84. SOME CLOUDINESS POSSIBLE WED NIGHT ESPECIALLY OVER THE WEST WHERE MODELS INDICATE AN UPTICK IN LOW LEVEL MOISTURE TRANSPORT GENERATED BY LIGHT BUT CONFLUENT AND UPSLOPE-DIRECTED LOW LEVEL FLOW. LOWS WITHIN A COUPLE DEGREES OF 60. -GIH && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... FOR THE PERIOD THURSDAY THROUGH THURSDAY NIGHT...A MID-LEVEL RIDGE AXIS BUILDS INTO CENTRAL NORTH CAROLINA THURSDAY...WITH THE AXIS MOVING EAST THURSDAY NIGHT. THE GUIDANCE HAS CONTINUED TO FORECAST VERY MINOR QPF IN CENTRAL NORTH CAROLINA DURING THIS PERIOD...WITH THE GFS FORECASTING THIS THURSDAY AND THE NAM MORE THURSDAY NIGHT. THE GFS DOES HAVE A RELATIVE MAXIMUM OF 850MB THETA-E AIR OVER CENTRAL NORTH CAROLINA THURSDAY WITH WEAK 850MB LIFT...BUT HEIGHTS ALOFT ARE RISING AND ANY LOW-LEVEL FORCING WITH ANY SURFACE BOUNDARY SHOULD BE WEAK. LIFTED INDICES ARE ABOVE 0C...AND MLCAPE IN THE LOWEST KM DOES NOT REGISTER AS BUFR SOUNDINGS FROM BOTH THE NAM AND GFS APPEAR CAPPED. GIVEN THE ORIENTATION OF 1000-500MB THICKNESSES...POSSIBLY A SHOWER COULD DRIFT SOUTHEAST FOLLOWING THE THERMAL WIND FROM HIGHER TERRAIN AND GET CLOSE TO THE NORTHWEST PIEDMONT THURSDAY AFTERNOON OR EVENING...BUT GIVEN THE UNCERTAINTY WILL KEEP THE FORECAST DRY. MOS GUIDANCE POPS ARE IN SINGLE FIGURES IN BOTH THE MAV AND THE MET. WITH AT LEAST A PARTLY SUNNY SKY EXPECTED...1000-850MB THICKNESSES WOULD SUGGEST LOWER TO MID 80S FOR HIGHS...IN CONJUNCTION WITH MAV AND MET MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT NEAR 60 IN THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN UNDERNEATH THE RIDGE AXIS ALOFT FOR A GOOD PART OF THE NIGHT...LOWER 60S ELSEWHERE AND POSSIBLY ON THE HIGHER END OF THE LOWER 60S TOWARD THE TRIAD AS THE WINDS OFF OF THE SURFACE START TO INCREASE OVERNIGHT. FOR THE PERIOD FRIDAY THROUGH TUESDAY...THE ECMWF AND THE GFS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF AN ELONGATED MID-LEVEL SHORTWAVE MOVING INTO CENTRAL NORTH CAROLINA BY 00Z SATURDAY AND THEN EAST OF THE AREA BY 12Z SATURDAY. ONE TREND HAS BEEN FOR THE MID-LEVEL RIDGE TO BE SLIGHTLY MORE AMPLIFIED... WHICH...IF THE TREND CONTINUES...COULD SLOW THE ONSET OF ANY SHOWERS OR THUNDERSTORMS DURING THE DAY FRIDAY. LAPSE RATES ON COARSE GFS AND ECMWF MODEL SOUNDINGS ARE NEAR MOIST ADIABATIC AT BEST...SO INSTABILITY SHOULD BE LIMITED. STILL...WITH WINDS OFF OF THE SURFACE INCREASING TO AT OR A LITTLE ABOVE 30KT AHEAD OF THE COLD FRONT... CURRENT THINKING IS THAT ANY STRONGER STORM COULD HAVE A GUSTY WIND...THOUGH NOT CONFIDENT CURENTLY IN THE PROBABILITY OF ISOLATED SEVERE WEATHER GIVEN THE MARGINAL LAPSE RATES. DRY CONDITIONS WILL BE FORECAST SATURDAY THROUGH SUNDAY...THOUGH THE ECMWF DOES CONTINUE TO FORECAST GREATER DIGGING WITH UPPER-LEVEL LOW PRESSURE MOVING THROUGH THE OHIO VALLEY AND EAST ACROSS AREAS JUST NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT. AGAIN...THE TREND OF THIS WILL NEED TO BE WATCHED...BUT CURRENTLY THE MID-LEVEL MOISTURE ASSOCIATED WITH THE UPPER LOW ON THE ECMWF STAYS NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT INTO EARLY SUNDAY. BEHIND THE COLD FRONT ON SATURDAY OR SATURDAY NIGHT...HOWEVER...SOME JET STREAK CIRRUS COULD OCCUR IF THE GFS AND ECMWF UPPER-LEVEL MOISTURE FORECASTS VERIFY IN CONJUNCTION WITH THE JET AXIS ALOFT. THE ECMWF IS ALSO MORE AMPLIFIED WITH ANOTHER IN A SERIES OF MID- LEVEL WAVES IN THE NORTHWEST FLOW...THIS ONE APPROACHING THE SOUTHERN APPALACHIANS MONDAY. THE GFS IS DRY WITH LITTLE FORCING... WHILE THE ECMWF HAS MORE OF A SURFACE REFLECTION WITH THE MID-LEVEL WAVE AND ENOUGH MID-LEVEL MOISTURE FOR LIGHT PRECIPITATION OVER THE WESTERN AND NORTHWEST PIEDMONT LATE MONDAY AFTERNOON OR MONDAY NIGHT. WITH SURFACE HIGH PRESSURE OVER THE GULF...IF THERE IS ANY PRECIPITATION MONDAY...THE THOUGHT IS IT WOULD BE MID-LEVEL DRIVEN AND MOSTLY LIGHT. FOR THIS FORECAST WILL TREND A LITTLE MORE PESSIMISTIC ON THE LAST DAY OF THE LONG-TERM PERIOD...INCREASING CLOUDS BUT KEEPING THE OVERALL FORECAST DRY. AFTER HIGHS IN THE MID 70S TO NEAR 80 FRIDAY AHEAD OF THE FRONT... BY SATURDAY NIGHT...AS THE GUIDANCE STILL SHOWS CHILLY 1000-850MB THICKNESSES INTO THE 1340S...THERE SHOULD BE AT LEAST A FEW 40S OVER THE WESTERN AND NORTHERN PIEDMONT. MODEST WARMING FOR THE END OF THE WEEKEND AND THE START OF NEXT WEEK. HIGHS SHOULD BE BACK AT LEAST IN THE LOWER TO MID 70S FOR MONDAY. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 1240 AM TUESDAY... ADVERSE AVIATION CONDITIONS ARE LIKELY TO HOLD OVER CENTRAL NC THROUGH 14Z OR 15Z THIS MORNING... WITH IMPROVEMENT TO VFR TO FOLLOW BY LATE MORNING... WHICH WILL HOLD THROUGH THE END OF THE TAF VALID PERIOD (06Z WED). THE MID LEVEL TROUGH AXIS OVER THE ERN CAROLINAS WILL CONTINUE TO SHIFT EAST AND OFFSHORE THIS MORNING... TAKING WITH IT THE MID/HIGH CLOUDS AS WELL AS ANY THREAT OF ADDITIONAL PATCHY LIGHT RAIN. THE CLEARING CLOUDS HOWEVER WILL FOSTER FURTHER DEVELOPMENT OF LOW STRATUS/FOG THIS MORNING. THESE IFR/LIFR CONDITIONS HOWEVER WILL BE FLEETING... WITH LOW CLOUDS/FOG NOT A SOLID DECK BUT IN DISCONTINUOUS PATCHES... MAKING THE TAFS CHALLENGING THIS MORNING. PILOTS SHOULD BE PARTICULARLY ALERT FOR POSSIBLE VFR HOLES WITHIN IFR/LIFR CONDITIONS THROUGH MID MORNING. OTHERWISE... ANY CIGS SHOULD BREAK UP BY 15Z OR 16Z... WITH VFR CONDITIONS THEN PREVAILING THROUGH THE AFTERNOON AND EVENING HOURS. SURFACE WINDS WILL REMAIN LIGHT/VARIABLE (MAINLY FROM THE NORTHWEST) MOSTLY UNDER 5 KTS TODAY/TONIGHT. LOOKING BEYOND 06Z EARLY WED MORNING... VFR CONDITIONS WILL PREVAIL THROUGH FRI... ALTHOUGH SHALLOW IFR GROUND FOG IS AGAIN POSSIBLE AREAWIDE 08Z-13Z EACH MORNING WED THROUGH FRI. A STRONG FRONTAL SYSTEM WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN WIDESPREAD SHOWERS/STORMS FRI AFTERNOON INTO FRI NIGHT. HIGH PRESSURE WILL THEN BUILD IN YIELDING VFR CONDITIONS SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NCZ007>011-021>028-038>043-073>077. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...DJF AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
300 AM EDT TUE SEP 30 2014 .SYNOPSIS...WEAK LOW PRESSURE OVER NORTHEAST FLORIDA WILL TRACK NORTHEASTWARD OFF THE SOUTHEAST COAST TODAY. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. A STRONG STORM SYSTEM WILL APPROACH FROM THE WEST ON FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 222 AM TUESDAY... TODAY... FIRST CONCERN EARLY THIS MORNING IS THE DEGREE OF FOG DEVELOPMENT OVER THE AREA THUS FAR. THE MID LEVEL SHORTWAVE TROUGH IS NOW HEADING EAST OFF THE CAROLINA COAST... WITH THE VEIL OF MID/HIGH CLOUDS DEPARTING ALONG WITH IT. THE DAMP GROUND COMBINED WITH THE CLEARING SKIES AND LIGHT/CALM WINDS SHOULD CONTINUE TO FOSTER DEVELOPMENT OF LOW CLOUDS AND FOG EARLY THIS MORNING... ALTHOUGH THE CURRENT PATCHY/FLEETING NATURE OF THESE CONDITIONS (SEVERAL SITES HAVE BOUNCED AROUND BETWEEN 1/4 MI AND 5 MI IN FOG THE LAST FEW HRS) GIVES US PAUSE AS TO THE NEED FOR A DENSE FOG ADVISORY. THE HRRR DEPICTS A FAIRLY SOLID DECK OF LOW CLOUDS/FOG FORMING OVER THE NEXT FEW HOURS HOWEVER. WILL CONTINUE TO MONITOR THE OBSERVED TRENDS. IF VSBYS DO DROP AND HOLD THERE FOR OVER AN HOUR... THEY`RE LIKELY TO HOLD FIRM THROUGH MID MORNING... GIVEN THE WEAK WIND FIELD THROUGH THE LOWEST FEW THOUSAND FEET RESULTING IN MINIMAL STIRRING/DISPERSION HORIZONTALLY OR VERTICALLY. WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY THROUGH MID MORNING TO ACCOUNT FOR THIS. THEN... ONCE HEATING AND SUBSEQUENT MIXING HELPS TO DISPERSE THE FOG/STRATUS... EXPECT A GOOD BIT OF SUNSHINE THROUGH THE DAY... WITH FLAT AFTERNOON STRATOCU LIKELY TO STAY SCATTERED AT WORST. WITH THICKNESSES CLOSE TO SEASONAL NORMALS... STILL LOOK FOR HIGHS WITHIN A FEW DEGREES OF 80. FOR TONIGHT: THE SURFACE LOW TRACKING TOWARD THE NE WELL OFF THE SE COAST WILL BE FAR ENOUGH TO OUR SE TO MINIMIZE ANY IMPACT ON CENTRAL NC. THE WEAK LOW LEVEL FLOW PATTERN HOLDS WITH A WEAK HIGH PRESSURE RIDGE SPANNING THE AREA AND A VERY WEAK SURFACE LOW/INVERTED TROUGH OVER PA/WV/VA... A REFLECTION OF THE CLIPPER MID LEVEL VORTEX NOW OVER ERN MI THAT IS EXPECTED TO CROSS THE MIDATLANTIC REGION REGION LATE TONIGHT THROUGH WED MORNING. MODELS VARY IN THEIR IMPACTS ON OUR WEATHER WITH THIS FEATURE... WITH THE NAM MUCH MORE BULLISH THAN THE GFS IN TAKING A SLUG OF 850-700 MB MOISTURE EAST ACROSS THE AREA TONIGHT. THIS SEEMS A BIT OVERDONE BUT IT IS SOMEWHAT SUPPORTED BY OBSERVED SOUNDINGS UPSTREAM... SO WILL RETAIN A FEW CLOUDS OVER THE AREA OVERNIGHT... AND LATER FORECASTS CAN INCREASE THIS COVERAGE IF LATER GUIDANCE SUPPORTS THE NAM. LOWS 57-60. -GIH && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 245 AM TUESDAY... AS NOTED ABOVE... WE SHOULD SEE AT LEAST SOME SCATTERED CLOUDS MAINLY OVER THE EAST WED MORNING. THE PRESENCE OR LACK OF SUCH CLOUDS WILL IMPACT HOW MUCH FOG FORMS WED MORNING. WE SHOULD SEE AT LEAST SOME LIGHT FOG TO START THE DAY... AND PERHAPS MORE DENSE IF THE AFOREMENTIONED CLIPPER-ASSOCIATED CLOUDS DO NOT HAPPEN. OTHERWISE... EXPECT A PARTLY TO MOSTLY SUNNY DAY. THE CLIPPER LOW WILL CROSS NEW ENGLAND AS THE STRONG VORTICITY MAX ROUNDS ITS BASE... SHIFTING OFF THE NJ COAST... AND WE SHOULD SEE A BIT MORE FLAT DAYTIME CUMULUS FROM THE TRIANGLE NORTH AND EAST CLOSER TO THE LOW. MODELS SHOW WEAK MID LEVEL RIDGING PUSHING IN FROM THE WEST LATE... BETWEEN THE DEPARTING CLIPPER AND A DEEPENING TROUGH COVERING THE EASTERN ROCKIES AND HIGH PLAINS LATE WED/WED NIGHT. WHILE MODELS SHOW A MINOR PERTURBATION TRACKING EASTWARD OVER THE SOUTHEAST STATES WED NIGHT... THIS SHOULD BE OF LITTLE CONSEQUENCE WITH DEEP DRY AIR MOVING IN. EXPECT DRY WEATHER THROUGH WED NIGHT. THICKNESSES ARE EXPECTED TO START WED ABOUT 10 M ABOVE NORMAL... SUPPORTING HIGHS ABOUT A CATEGORY ABOVE NORMAL... 80-84. SOME CLOUDINESS POSSIBLE WED NIGHT ESPECIALLY OVER THE WEST WHERE MODELS INDICATE AN UPTICK IN LOW LEVEL MOISTURE TRANSPORT GENERATED BY LIGHT BUT CONFLUENT AND UPSLOPE-DIRECTED LOW LEVEL FLOW. LOWS WITHIN A COUPLE DEGREES OF 60. -GIH && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 AM TUESDAY... FOR THE PERIOD THURSDAY THROUGH THURSDAY NIGHT...A MID-LEVEL RIDGE AXIS BUILDS INTO CENTRAL NORTH CAROLINA THURSDAY...WITH THE AXIS MOVING EAST THURSDAY NIGHT. THE GUIDANCE HAS CONTINUED TO FORECAST VERY MINOR QPF IN CENTRAL NORTH CAROLINA DURING THIS PERIOD...WITH THE GFS FORECASTING THIS THURSDAY AND THE NAM MORE THURSDAY NIGHT. THE GFS DOES HAVE A RELATIVE MAXIMUM OF 850MB THETA-E AIR OVER CENTRAL NORTH CAROLINA THURSDAY WITH WEAK 850MB LIFT...BUT HEIGHTS ALOFT ARE RISING AND ANY LOW-LEVEL FORCING WITH ANY SURFACE BOUNDARY SHOULD BE WEAK. LIFTED INDICES ARE ABOVE 0C...AND MLCAPE IN THE LOWEST KM DOES NOT REGISTER AS BUFR SOUNDINGS FROM BOTH THE NAM AND GFS APPEAR CAPPED. GIVEN THE ORIENTATION OF 1000-500MB THICKNESSES...POSSIBLY A SHOWER COULD DRIFT SOUTHEAST FOLLOWING THE THERMAL WIND FROM HIGHER TERRAIN AND GET CLOSE TO THE NORTHWEST PIEDMONT THURSDAY AFTERNOON OR EVENING...BUT GIVEN THE UNCERTAINTY WILL KEEP THE FORECAST DRY. MOS GUIDANCE POPS ARE IN SINGLE FIGURES IN BOTH THE MAV AND THE MET. WITH AT LEAST A PARTLY SUNNY SKY EXPECTED...1000-850MB THICKNESSES WOULD SUGGEST LOWER TO MID 80S FOR HIGHS...IN CONJUNCTION WITH MAV AND MET MOS GUIDANCE. OVERNIGHT LOWS THURSDAY NIGHT NEAR 60 IN THE NORTHEAST PIEDMONT AND NORTHERN COASTAL PLAIN UNDERNEATH THE RIDGE AXIS ALOFT FOR A GOOD PART OF THE NIGHT...LOWER 60S ELSEWHERE AND POSSIBLY ON THE HIGHER END OF THE LOWER 60S TOWARD THE TRIAD AS THE WINDS OFF OF THE SURFACE START TO INCREASE OVERNIGHT. FOR THE PERIOD FRIDAY THROUGH TUESDAY...THE ECMWF AND THE GFS CONTINUE TO BE IN FAIRLY GOOD AGREEMENT WITH THE TIMING OF AN ELONGATED MID-LEVEL SHORTWAVE MOVING INTO CENTRAL NORTH CAROLINA BY 00Z SATURDAY AND THEN EAST OF THE AREA BY 12Z SATURDAY. ONE TREND HAS BEEN FOR THE MID-LEVEL RIDGE TO BE SLIGHTLY MORE AMPLIFIED... WHICH...IF THE TREND CONTINUES...COULD SLOW THE ONSET OF ANY SHOWERS OR THUNDERSTORMS DURING THE DAY FRIDAY. LAPSE RATES ON COARSE GFS AND ECMWF MODEL SOUNDINGS ARE NEAR MOIST ADIABATIC AT BEST...SO INSTABILITY SHOULD BE LIMITED. STILL...WITH WINDS OFF OF THE SURFACE INCREASING TO AT OR A LITTLE ABOVE 30KT AHEAD OF THE COLD FRONT... CURRENT THINKING IS THAT ANY STRONGER STORM COULD HAVE A GUSTY WIND...THOUGH NOT CONFIDENT CURENTLY IN THE PROBABILITY OF ISOLATED SEVERE WEATHER GIVEN THE MARGINAL LAPSE RATES. DRY CONDITIONS WILL BE FORECAST SATURDAY THROUGH SUNDAY...THOUGH THE ECMWF DOES CONTINUE TO FORECAST GREATER DIGGING WITH UPPER-LEVEL LOW PRESSURE MOVING THROUGH THE OHIO VALLEY AND EAST ACROSS AREAS JUST NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT. AGAIN...THE TREND OF THIS WILL NEED TO BE WATCHED...BUT CURRENTLY THE MID-LEVEL MOISTURE ASSOCIATED WITH THE UPPER LOW ON THE ECMWF STAYS NORTH OF CENTRAL NORTH CAROLINA SATURDAY NIGHT INTO EARLY SUNDAY. BEHIND THE COLD FRONT ON SATURDAY OR SATURDAY NIGHT...HOWEVER...SOME JET STREAK CIRRUS COULD OCCUR IF THE GFS AND ECMWF UPPER-LEVEL MOISTURE FORECASTS VERIFY IN CONJUNCTION WITH THE JET AXIS ALOFT. THE ECMWF IS ALSO MORE AMPLIFIED WITH ANOTHER IN A SERIES OF MID- LEVEL WAVES IN THE NORTHWEST FLOW...THIS ONE APPROACHING THE SOUTHERN APPALACHIANS MONDAY. THE GFS IS DRY WITH LITTLE FORCING... WHILE THE ECMWF HAS MORE OF A SURFACE REFLECTION WITH THE MID-LEVEL WAVE AND ENOUGH MID-LEVEL MOISTURE FOR LIGHT PRECIPITATION OVER THE WESTERN AND NORTHWEST PIEDMONT LATE MONDAY AFTERNOON OR MONDAY NIGHT. WITH SURFACE HIGH PRESSURE OVER THE GULF...IF THERE IS ANY PRECIPITATION MONDAY...THE THOUGHT IS IT WOULD BE MID-LEVEL DRIVEN AND MOSTLY LIGHT. FOR THIS FORECAST WILL TREND A LITTLE MORE PESSIMISTIC ON THE LAST DAY OF THE LONG-TERM PERIOD...INCREASING CLOUDS BUT KEEPING THE OVERALL FORECAST DRY. AFTER HIGHS IN THE MID 70S TO NEAR 80 FRIDAY AHEAD OF THE FRONT... BY SATURDAY NIGHT...AS THE GUIDANCE STILL SHOWS CHILLY 1000-850MB THICKNESSES INTO THE 1340S...THERE SHOULD BE AT LEAST A FEW 40S OVER THE WESTERN AND NORTHERN PIEDMONT. MODEST WARMING FOR THE END OF THE WEEKEND AND THE START OF NEXT WEEK. HIGHS SHOULD BE BACK AT LEAST IN THE LOWER TO MID 70S FOR MONDAY. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 1240 AM TUESDAY... ADVERSE AVIATION CONDITIONS ARE LIKELY TO HOLD OVER CENTRAL NC THROUGH 14Z OR 15Z THIS MORNING... WITH IMPROVEMENT TO VFR TO FOLLOW BY LATE MORNING... WHICH WILL HOLD THROUGH THE END OF THE TAF VALID PERIOD (06Z WED). THE MID LEVEL TROUGH AXIS OVER THE ERN CAROLINAS WILL CONTINUE TO SHIFT EAST AND OFFSHORE THIS MORNING... TAKING WITH IT THE MID/HIGH CLOUDS AS WELL AS ANY THREAT OF ADDITIONAL PATCHY LIGHT RAIN. THE CLEARING CLOUDS HOWEVER WILL FOSTER FURTHER DEVELOPMENT OF LOW STRATUS/FOG THIS MORNING. THESE IFR/LIFR CONDITIONS HOWEVER WILL BE FLEETING... WITH LOW CLOUDS/FOG NOT A SOLID DECK BUT IN DISCONTINUOUS PATCHES... MAKING THE TAFS CHALLENGING THIS MORNING. PILOTS SHOULD BE PARTICULARLY ALERT FOR POSSIBLE VFR HOLES WITHIN IFR/LIFR CONDITIONS THROUGH MID MORNING. OTHERWISE... ANY CIGS SHOULD BREAK UP BY 15Z OR 16Z... WITH VFR CONDITIONS THEN PREVAILING THROUGH THE AFTERNOON AND EVENING HOURS. SURFACE WINDS WILL REMAIN LIGHT/VARIABLE (MAINLY FROM THE NORTHWEST) MOSTLY UNDER 5 KTS TODAY/TONIGHT. LOOKING BEYOND 06Z EARLY WED MORNING... VFR CONDITIONS WILL PREVAIL THROUGH FRI... ALTHOUGH SHALLOW IFR GROUND FOG IS AGAIN POSSIBLE AREAWIDE 08Z-13Z EACH MORNING WED THROUGH FRI. A STRONG FRONTAL SYSTEM WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN WIDESPREAD SHOWERS/STORMS FRI AFTERNOON INTO FRI NIGHT. HIGH PRESSURE WILL THEN BUILD IN YIELDING VFR CONDITIONS SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...DJF AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
245 AM EDT TUE SEP 30 2014 .SYNOPSIS...WEAK LOW PRESSURE OVER NORTHEAST FLORIDA WILL TRACK NORTHEASTWARD OFF THE SOUTHEAST COAST TODAY. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. A STRONG STORM SYSTEM WILL APPROACH FROM THE WEST ON FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 222 AM TUESDAY... TODAY... FIRST CONCERN EARLY THIS MORNING IS THE DEGREE OF FOG DEVELOPMENT OVER THE AREA THUS FAR. THE MID LEVEL SHORTWAVE TROUGH IS NOW HEADING EAST OFF THE CAROLINA COAST... WITH THE VEIL OF MID/HIGH CLOUDS DEPARTING ALONG WITH IT. THE DAMP GROUND COMBINED WITH THE CLEARING SKIES AND LIGHT/CALM WINDS SHOULD CONTINUE TO FOSTER DEVELOPMENT OF LOW CLOUDS AND FOG EARLY THIS MORNING... ALTHOUGH THE CURRENT PATCHY/FLEETING NATURE OF THESE CONDITIONS (SEVERAL SITES HAVE BOUNCED AROUND BETWEEN 1/4 MI AND 5 MI IN FOG THE LAST FEW HRS) GIVES US PAUSE AS TO THE NEED FOR A DENSE FOG ADVISORY. THE HRRR DEPICTS A FAIRLY SOLID DECK OF LOW CLOUDS/FOG FORMING OVER THE NEXT FEW HOURS HOWEVER. WILL CONTINUE TO MONITOR THE OBSERVED TRENDS. IF VSBYS DO DROP AND HOLD THERE FOR OVER AN HOUR... THEY`RE LIKELY TO HOLD FIRM THROUGH MID MORNING... GIVEN THE WEAK WIND FIELD THROUGH THE LOWEST FEW THOUSAND FEET RESULTING IN MINIMAL STIRRING/DISPERSION HORIZONTALLY OR VERTICALLY. WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY THROUGH MID MORNING TO ACCOUNT FOR THIS. THEN... ONCE HEATING AND SUBSEQUENT MIXING HELPS TO DISPERSE THE FOG/STRATUS... EXPECT A GOOD BIT OF SUNSHINE THROUGH THE DAY... WITH FLAT AFTERNOON STRATOCU LIKELY TO STAY SCATTERED AT WORST. WITH THICKNESSES CLOSE TO SEASONAL NORMALS... STILL LOOK FOR HIGHS WITHIN A FEW DEGREES OF 80. FOR TONIGHT: THE SURFACE LOW TRACKING TOWARD THE NE WELL OFF THE SE COAST WILL BE FAR ENOUGH TO OUR SE TO MINIMIZE ANY IMPACT ON CENTRAL NC. THE WEAK LOW LEVEL FLOW PATTERN HOLDS WITH A WEAK HIGH PRESSURE RIDGE SPANNING THE AREA AND A VERY WEAK SURFACE LOW/INVERTED TROUGH OVER PA/WV/VA... A REFLECTION OF THE CLIPPER MID LEVEL VORTEX NOW OVER ERN MI THAT IS EXPECTED TO CROSS THE MIDATLANTIC REGION REGION LATE TONIGHT THROUGH WED MORNING. MODELS VARY IN THEIR IMPACTS ON OUR WEATHER WITH THIS FEATURE... WITH THE NAM MUCH MORE BULLISH THAN THE GFS IN TAKING A SLUG OF 850-700 MB MOISTURE EAST ACROSS THE AREA TONIGHT. THIS SEEMS A BIT OVERDONE BUT IT IS SOMEWHAT SUPPORTED BY OBSERVED SOUNDINGS UPSTREAM... SO WILL RETAIN A FEW CLOUDS OVER THE AREA OVERNIGHT... AND LATER FORECASTS CAN INCREASE THIS COVERAGE IF LATER GUIDANCE SUPPORTS THE NAM. LOWS 57-60. -GIH && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 245 AM TUESDAY... AS NOTED ABOVE... WE SHOULD SEE AT LEAST SOME SCATTERED CLOUDS MAINLY OVER THE EAST WED MORNING. THE PRESENCE OR LACK OF SUCH CLOUDS WILL IMPACT HOW MUCH FOG FORMS WED MORNING. WE SHOULD SEE AT LEAST SOME LIGHT FOG TO START THE DAY... AND PERHAPS MORE DENSE IF THE AFOREMENTIONED CLIPPER-ASSOCIATED CLOUDS DO NOT HAPPEN. OTHERWISE... EXPECT A PARTLY TO MOSTLY SUNNY DAY. THE CLIPPER LOW WILL CROSS NEW ENGLAND AS THE STRONG VORTICITY MAX ROUNDS ITS BASE... SHIFTING OFF THE NJ COAST... AND WE SHOULD SEE A BIT MORE FLAT DAYTIME CUMULUS FROM THE TRIANGLE NORTH AND EAST CLOSER TO THE LOW. MODELS SHOW WEAK MID LEVEL RIDGING PUSHING IN FROM THE WEST LATE... BETWEEN THE DEPARTING CLIPPER AND A DEEPENING TROUGH COVERING THE EASTERN ROCKIES AND HIGH PLAINS LATE WED/WED NIGHT. WHILE MODELS SHOW A MINOR PERTURBATION TRACKING EASTWARD OVER THE SOUTHEAST STATES WED NIGHT... THIS SHOULD BE OF LITTLE CONSEQUENCE WITH DEEP DRY AIR MOVING IN. EXPECT DRY WEATHER THROUGH WED NIGHT. THICKNESSES ARE EXPECTED TO START WED ABOUT 10 M ABOVE NORMAL... SUPPORTING HIGHS ABOUT A CATEGORY ABOVE NORMAL... 80-84. SOME CLOUDINESS POSSIBLE WED NIGHT ESPECIALLY OVER THE WEST WHERE MODELS INDICATE AN UPTICK IN LOW LEVEL MOISTURE TRANSPORT GENERATED BY LIGHT BUT CONFLUENT AND UPSLOPE-DIRECTED LOW LEVEL FLOW. LOWS WITHIN A COUPLE DEGREES OF 60. -GIH && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 120 PM MONDAY... FAIR WEATHER IS EXPECTED THURSDAY AS SFC HIGH PRESSURE...ALONG WITH SHORT WAVE RIDGING ALOFT...SET UP OVER THE AREA. FORECAST SOUNDINGS ARE FAIRLY DRY...ALTHOUGH SUGGEST SOME AFTERNOON SHALLOW CU BENEATH THE MID-LEVEL INVERSION. LOW LEVEL THICKNESS AROUND 1395 SUGGESTS HIGHS A FEW DEGREES ABOVE NORMAL... HIGHS AROUND 80 AND LOWS AROUND 60. THE NEXT WEATHER-MAKER FOR US WILL BE A COLD FRONT THAT`S NOW PROGGED TO SWEEP ACROSS THE STATE LATE ON FRIDAY. FORECAST SOUNDINGS SHOW THE HIGH CLOUDS THICKENING AHEAD OF IT THURSDAY NIGHT...THEN RAPID MID AND LOW LEVEL MOISTURE INCREASE DURING THE AFTERNOON FRIDAY AS SW FLOW IN THE BL INCREASES AHEAD OF THE FRONT. THE END RESULT NOWS LOOKS LIKE A BAND OF SHOWERS JUST AHEAD OF THE FRONT WILL QUICKLY MOVE ACROSS CENTRAL NC PERHAPS DURING THE LATE AFTERNOON AND EVENING HOURS FRIDAY. AS FOR INTENSITY...MOST OF THE PRECIP SHOULD BE OF SHOWER VARIETY...BUT FORECAST SOUNDINGS DO SHOW SOME SKINNY CAPE AND THE POTENTIAL FOR AN ISOLATED THUNDERSTORM... BUT MORE NOTABLY 30-40 KTS OF BULK SHEAR...SO WILL NEED TO KEEP AN EYE ON INSTABILITY TRENDS WITH FUTURE MODELS RUNS. OF COURSE THE TIMING OF THIS WILL BE FINE-TUNED AS WE GET A LITTLE CLOSER...SO IF YOU HAVE OUTDOOR EVENTS FRIDAY AFTERNOON AND/OR EVENING...YOU`LL DEFINITELY WANT TO CHECK BACK LATER THIS WEEK FOR AN UPDATE. NOW LOOKS LIKE THE FRONT WILL BE WELL OFF THE COAST BY SATURDAY MORNING...WITH A COOLING AND DRYING TREND IN ITS WAKE FOR THIS WEEKEND. A LITTLE BREEZY ON SATURDAY IN THE TIGHT PRES GRADIENT AS THE HIGH`S BUILDING IN...BUT OVERALL SHOULD SEE DECENT AMOUNT OF SUNSHINE BOTH DAYS. TEMPS WILL FALL BACK CLOSER TO - OR PERHAPS A LITTLE BELOW- NORMAL BEHIND THE FRONT...HIGHS IN THE MID 70S AND LOWS IN THE MID 50S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 1240 AM TUESDAY... ADVERSE AVIATION CONDITIONS ARE LIKELY TO HOLD OVER CENTRAL NC THROUGH 14Z OR 15Z THIS MORNING... WITH IMPROVEMENT TO VFR TO FOLLOW BY LATE MORNING... WHICH WILL HOLD THROUGH THE END OF THE TAF VALID PERIOD (06Z WED). THE MID LEVEL TROUGH AXIS OVER THE ERN CAROLINAS WILL CONTINUE TO SHIFT EAST AND OFFSHORE THIS MORNING... TAKING WITH IT THE MID/HIGH CLOUDS AS WELL AS ANY THREAT OF ADDITIONAL PATCHY LIGHT RAIN. THE CLEARING CLOUDS HOWEVER WILL FOSTER FURTHER DEVELOPMENT OF LOW STRATUS/FOG THIS MORNING. THESE IFR/LIFR CONDITIONS HOWEVER WILL BE FLEETING... WITH LOW CLOUDS/FOG NOT A SOLID DECK BUT IN DISCONTINUOUS PATCHES... MAKING THE TAFS CHALLENGING THIS MORNING. PILOTS SHOULD BE PARTICULARLY ALERT FOR POSSIBLE VFR HOLES WITHIN IFR/LIFR CONDITIONS THROUGH MID MORNING. OTHERWISE... ANY CIGS SHOULD BREAK UP BY 15Z OR 16Z... WITH VFR CONDITIONS THEN PREVAILING THROUGH THE AFTERNOON AND EVENING HOURS. SURFACE WINDS WILL REMAIN LIGHT/VARIABLE (MAINLY FROM THE NORTHWEST) MOSTLY UNDER 5 KTS TODAY/TONIGHT. LOOKING BEYOND 06Z EARLY WED MORNING... VFR CONDITIONS WILL PREVAIL THROUGH FRI... ALTHOUGH SHALLOW IFR GROUND FOG IS AGAIN POSSIBLE AREAWIDE 08Z-13Z EACH MORNING WED THROUGH FRI. A STRONG FRONTAL SYSTEM WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN WIDESPREAD SHOWERS/STORMS FRI AFTERNOON INTO FRI NIGHT. HIGH PRESSURE WILL THEN BUILD IN YIELDING VFR CONDITIONS SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...NP AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
222 AM EDT TUE SEP 30 2014 .SYNOPSIS...WEAK LOW PRESSURE OVER NORTHEAST FLORIDA WILL TRACK NORTHEASTWARD OFF THE SOUTHEAST COAST TODAY. WEAK HIGH PRESSURE WILL BUILD OVER THE AREA FROM THE NORTH WEDNESDAY THROUGH THURSDAY. A STRONG STORM SYSTEM WILL APPROACH FROM THE WEST ON FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 222 AM TUESDAY... TODAY... FIRST CONCERN EARLY THIS MORNING IS THE DEGREE OF FOG DEVELOPMENT OVER THE AREA THUS FAR. THE MID LEVEL SHORTWAVE TROUGH IS NOW HEADING EAST OFF THE CAROLINA COAST... WITH THE VEIL OF MID/HIGH CLOUDS DEPARTING ALONG WITH IT. THE DAMP GROUND COMBINED WITH THE CLEARING SKIES AND LIGHT/CALM WINDS SHOULD CONTINUE TO FOSTER DEVELOPMENT OF LOW CLOUDS AND FOG EARLY THIS MORNING... ALTHOUGH THE CURRENT PATCHY/FLEETING NATURE OF THESE CONDITIONS (SEVERAL SITES HAVE BOUNCED AROUND BETWEEN 1/4 MI AND 5 MI IN FOG THE LAST FEW HRS) GIVES US PAUSE AS TO THE NEED FOR A DENSE FOG ADVISORY. THE HRRR DEPICTS A FAIRLY SOLID DECK OF LOW CLOUDS/FOG FORMING OVER THE NEXT FEW HOURS HOWEVER. WILL CONTINUE TO MONITOR THE OBSERVED TRENDS. IF VSBYS DO DROP AND HOLD THERE FOR OVER AN HOUR... THEY`RE LIKELY TO HOLD FIRM THROUGH MID MORNING... GIVEN THE WEAK WIND FIELD THROUGH THE LOWEST FEW THOUSAND FEET RESULTING IN MINIMAL STIRRING/DISPERSION HORIZONTALLY OR VERTICALLY. WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY THROUGH MID MORNING TO ACCOUNT FOR THIS. THEN... ONCE HEATING AND SUBSEQUENT MIXING HELPS TO DISPERSE THE FOG/STRATUS... EXPECT A GOOD BIT OF SUNSHINE THROUGH THE DAY... WITH FLAT AFTERNOON STRATOCU LIKELY TO STAY SCATTERED AT WORST. WITH THICKNESSES CLOSE TO SEASONAL NORMALS... STILL LOOK FOR HIGHS WITHIN A FEW DEGREES OF 80. FOR TONIGHT: THE SURFACE LOW TRACKING TOWARD THE NE WELL OFF THE SE COAST WILL BE FAR ENOUGH TO OUR SE TO MINIMIZE ANY IMPACT ON CENTRAL NC. THE WEAK LOW LEVEL FLOW PATTERN HOLDS WITH A WEAK HIGH PRESSURE RIDGE SPANNING THE AREA AND A VERY WEAK SURFACE LOW/INVERTED TROUGH OVER PA/WV/VA... A REFLECTION OF THE CLIPPER MID LEVEL VORTEX NOW OVER ERN MI THAT IS EXPECTED TO CROSS THE MIDATLANTIC REGION REGION LATE TONIGHT THROUGH WED MORNING. MODELS VARY IN THEIR IMPACTS ON OUR WEATHER WITH THIS FEATURE... WITH THE NAM MUCH MORE BULLISH THAN THE GFS IN TAKING A SLUG OF 850-700 MB MOISTURE EAST ACROSS THE AREA TONIGHT. THIS SEEMS A BIT OVERDONE BUT IT IS SOMEWHAT SUPPORTED BY OBSERVED SOUNDINGS UPSTREAM... SO WILL RETAIN A FEW CLOUDS OVER THE AREA OVERNIGHT... AND LATER FORECASTS CAN INCREASE THIS COVERAGE IF LATER GUIDANCE SUPPORTS THE NAM. LOWS 57-60. -GIH && .SHORT TERM /WEDNESDAY THROUGH WEDNESDAY NIGHT/... AS OF 1200 PM MONDAY... TO BE UPDATED SHORTLY. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 120 PM MONDAY... FAIR WEATHER IS EXPECTED THURSDAY AS SFC HIGH PRESSURE...ALONG WITH SHORT WAVE RIDGING ALOFT...SET UP OVER THE AREA. FORECAST SOUNDINGS ARE FAIRLY DRY...ALTHOUGH SUGGEST SOME AFTERNOON SHALLOW CU BENEATH THE MID-LEVEL INVERSION. LOW LEVEL THICKNESS AROUND 1395 SUGGESTS HIGHS A FEW DEGREES ABOVE NORMAL... HIGHS AROUND 80 AND LOWS AROUND 60. THE NEXT WEATHER-MAKER FOR US WILL BE A COLD FRONT THAT`S NOW PROGGED TO SWEEP ACROSS THE STATE LATE ON FRIDAY. FORECAST SOUNDINGS SHOW THE HIGH CLOUDS THICKENING AHEAD OF IT THURSDAY NIGHT...THEN RAPID MID AND LOW LEVEL MOISTURE INCREASE DURING THE AFTERNOON FRIDAY AS SW FLOW IN THE BL INCREASES AHEAD OF THE FRONT. THE END RESULT NOWS LOOKS LIKE A BAND OF SHOWERS JUST AHEAD OF THE FRONT WILL QUICKLY MOVE ACROSS CENTRAL NC PERHAPS DURING THE LATE AFTERNOON AND EVENING HOURS FRIDAY. AS FOR INTENSITY...MOST OF THE PRECIP SHOULD BE OF SHOWER VARIETY...BUT FORECAST SOUNDINGS DO SHOW SOME SKINNY CAPE AND THE POTENTIAL FOR AN ISOLATED THUNDERSTORM... BUT MORE NOTABLY 30-40 KTS OF BULK SHEAR...SO WILL NEED TO KEEP AN EYE ON INSTABILITY TRENDS WITH FUTURE MODELS RUNS. OF COURSE THE TIMING OF THIS WILL BE FINE-TUNED AS WE GET A LITTLE CLOSER...SO IF YOU HAVE OUTDOOR EVENTS FRIDAY AFTERNOON AND/OR EVENING...YOU`LL DEFINITELY WANT TO CHECK BACK LATER THIS WEEK FOR AN UPDATE. NOW LOOKS LIKE THE FRONT WILL BE WELL OFF THE COAST BY SATURDAY MORNING...WITH A COOLING AND DRYING TREND IN ITS WAKE FOR THIS WEEKEND. A LITTLE BREEZY ON SATURDAY IN THE TIGHT PRES GRADIENT AS THE HIGH`S BUILDING IN...BUT OVERALL SHOULD SEE DECENT AMOUNT OF SUNSHINE BOTH DAYS. TEMPS WILL FALL BACK CLOSER TO - OR PERHAPS A LITTLE BELOW- NORMAL BEHIND THE FRONT...HIGHS IN THE MID 70S AND LOWS IN THE MID 50S. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 1240 AM TUESDAY... ADVERSE AVIATION CONDITIONS ARE LIKELY TO HOLD OVER CENTRAL NC THROUGH 14Z OR 15Z THIS MORNING... WITH IMPROVEMENT TO VFR TO FOLLOW BY LATE MORNING... WHICH WILL HOLD THROUGH THE END OF THE TAF VALID PERIOD (06Z WED). THE MID LEVEL TROUGH AXIS OVER THE ERN CAROLINAS WILL CONTINUE TO SHIFT EAST AND OFFSHORE THIS MORNING... TAKING WITH IT THE MID/HIGH CLOUDS AS WELL AS ANY THREAT OF ADDITIONAL PATCHY LIGHT RAIN. THE CLEARING CLOUDS HOWEVER WILL FOSTER FURTHER DEVELOPMENT OF LOW STRATUS/FOG THIS MORNING. THESE IFR/LIFR CONDITIONS HOWEVER WILL BE FLEETING... WITH LOW CLOUDS/FOG NOT A SOLID DECK BUT IN DISCONTINUOUS PATCHES... MAKING THE TAFS CHALLENGING THIS MORNING. PILOTS SHOULD BE PARTICULARLY ALERT FOR POSSIBLE VFR HOLES WITHIN IFR/LIFR CONDITIONS THROUGH MID MORNING. OTHERWISE... ANY CIGS SHOULD BREAK UP BY 15Z OR 16Z... WITH VFR CONDITIONS THEN PREVAILING THROUGH THE AFTERNOON AND EVENING HOURS. SURFACE WINDS WILL REMAIN LIGHT/VARIABLE (MAINLY FROM THE NORTHWEST) MOSTLY UNDER 5 KTS TODAY/TONIGHT. LOOKING BEYOND 06Z EARLY WED MORNING... VFR CONDITIONS WILL PREVAIL THROUGH FRI... ALTHOUGH SHALLOW IFR GROUND FOG IS AGAIN POSSIBLE AREAWIDE 08Z-13Z EACH MORNING WED THROUGH FRI. A STRONG FRONTAL SYSTEM WILL BRING A GOOD CHANCE OF SUB-VFR CONDITIONS WITHIN WIDESPREAD SHOWERS/STORMS FRI AFTERNOON INTO FRI NIGHT. HIGH PRESSURE WILL THEN BUILD IN YIELDING VFR CONDITIONS SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM... LONG TERM...NP AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
120 AM EDT TUE SEP 30 2014 .SYNOPSIS... LOW PRESSURE OFF THE SOUTHEAST UNITED STATES COAST WILL MOVE FARTHER OFFSHORE THROUGH TODAY. WEAK HIGH PRESSURE WILL BUILD ACROSS THE CAROLINAS THROUGH THURSDAY. A STRONG COLD FRONT WILL PUSH ACROSS THE AREA EARLY SATURDAY ACCOMPANIED BY THE NEXT CHANCE OF SHOWERS AND THUNDERSTORMS. MUCH COOLER FALL WEATHER IS EXPECTED EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... AS OF 1045 PM MONDAY...LATEST 88D TRENDS ILLUSTRATE THE MAIN RAIN SHIELD HAS MOVED OFF THE CAROLINA COASTS. THIS LEAVES PATCHY LIGHT RAIN AND DRIZZLE FOR THE PRE-DAWN HOURS. PLENTY OF MOISTURE THRU THE LOWER LEVELS OF THE ATM COLUMN AND AM HESITANT TO PLACE FOG IN THE FCST. WINDS ALONG THE IMMEDIATE COAST SHOULD STAY ACTIVE VIA THE LOW DEVELOPING OFFSHORE FROM GA-SC COASTS. HAVE KEPT A STRATUS CLOUD DECK THRUOUT THE OVERNIGHT...AND UP THRU SEVERAL HOURS AFTER DAYBREAK TUE. THIS SHOULD ALSO HOLD THE FOG TO A MINIMUM. MIN TEMP FCST STILL IN THE BALLPARK AND SEE NO REASON TO TWEAK. PREVIOUS DISCUSSION........................................... AS OF 730 PM MONDAY...BASED ON LATEST RADAR TRENDS...THE PCPN CONSISTING OF LIGHT RAIN OR DRIZZLE...IS COMING TO AN END FROM WSW TO ENE ACROSS THE EASTERN CAROLINAS. LATEST HRRR ALSO ILLUSTRATES THE MAIN PCPN SHIELD SHOULD BE OFF THE COAST BY 1AM TO 3AM TUESDAY...LEAVING PATCHY LIGHT RAIN OR DRIZZLE FOR THE REMAINDER OF THE PRE-DAWN TUE HOURS. POPS FOR THE OVERNIGHT PERIOD HAVE BEEN RE-CALCULATED AS A RESULT. BECAME MORE PESSIMISTIC WITH ANY CLEARING DUE TO PLENTY OF MOISTURE AVBL FROM THE SFC THRU 600 MB AS SHOWN BY THE LATEST NAMBUFR SOUNDINGS ACROSS THE FA...WELL AFTER THE TIME PCPN COMES TO AN END. VERY LITTLE TWEAKING TO TONIGHTS MINS NEEDED. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...AN UPPER LEVEL TROUGH WILL BE MOVING OFF THE CAROLINA COAST AROUND DAYBREAK TUESDAY...WITH A DRY PUNCH IN THE MID LEVELS SCOURING OUT ALL THE MOISTURE ABOVE 700 MB. A FLAT UPPER RIDGE WILL BUILD INTO THE REGION WEDNESDAY. CLOCKWISE CIRCULATION AROUND SURFACE LOW PRESSURE (MOVING EAST THROUGH THE GEORGIA OFFSHORE WATERS) WILL KEEP NORTHEAST WINDS IN THE LOW LEVELS WITH ONLY A GRADUAL DRYING/CLEARING TREND EXPECTED. ALONG THE COAST THIS MEANS IT MAY TAKE UNTIL EARLY AFTERNOON FOR LOW CLOUDS TO BREAK...BUT INLAND SKIES SHOULD TURN PARTLY CLOUDY DURING THE MORNING WITH MOSTLY SUNNY CONDITIONS DURING THE AFTERNOON. ALTHOUGH THE 12Z GFS LOOKS MOST REASONABLE WITH MASS FIELDS IT MAY BE A LITTLE AGGRESSIVE CLEARING CLOUDS ALONG THE COAST AND I HAVE TRENDED MY FORECAST HIGHS A LITTLE BENEATH THE 12Z GFS MOS AS A RESULT...79-81 OVER SE NORTH CAROLINA AND 80-82 OVER NE SOUTH CAROLINA. MOISTURE TRAPPED UNDER A MODEST SUBSIDENCE INVERSION MAY LEAD TO A FEW EVENING CLOUDS BUT SKIES SHOULD BECOME CLEAR BEFORE MIDNIGHT. BOUNDARY LAYER WINDS MAY BE A TOUCH TOO STRONG FOR FOG ALTHOUGH THE MOISTURE PROFILES OTHERWISE LOOK PRETTY GOOD FOR FOG. LOWS SHOULD FALL TO AROUND 60 INLAND...WITH LOWER 60S COASTAL AREAS AND SOME MID 60S ON THE BEACHES. WITH EVEN LESS BOUNDARY LAYER MOISTURE (PRECIP WATER VALUES 0.8 TO 0.9 INCHES) EXPECTED ON WEDNESDAY SKIES SHOULD BE ESSENTIALLY CLEAR. LIGHT NORTHEAST WINDS WILL VEER SOUTHEASTERLY ALONG THE COAST WITH A LIGHT SEABREEZE CIRCULATION. HIGHS SHOULD REACH THE MID 80S ACROSS THE SC PEE DEE REGION...LOWER 80S ELSEWHERE EXCEPT A LITTLE COOLER AT THE BEACHES WHERE WATER TEMPERATURES HAVE BEGUN THEIR SEASONAL DROP...NOW IN THE MID-UPPER 70S. VERY LIGHT WINDS EXPECTED WEDNESDAY NIGHT WOULD ARGUE FOR FOG...BUT BOUNDARY LAYER MOISTURE MAY NOT BE QUITE DEEP ENOUGH ACCORDING TO THE 12Z MODEL SUITE. LOWS SHOULD FALL INTO THE LOWER 60S WITH MID-UPPER 60S AT THE BEACHES. && .LONG TERM /THURSDAY THROUGH MONDAY/... AS OF 300 PM MONDAY...DEEP MID LEVEL TROUGHING WILL BE THE MAIN STORY FOR THE EXTENDED FORECAST BEGINNING FRIDAY THROUGH THE WEEKEND. THIS FEATURE WILL ALLOW A COLD FRONT TO MOVE ACROSS THE AREA LATE FRIDAY/EARLY SATURDAY WITH DECENT FORCING AND WITH GUIDANCE SHOWING AN EVEN DEEPER TROUGH...MOISTURE ADVECTION FROM THE ATLANTIC IS STRONGER HENCE SLIGHTLY HIGHER POPS FOR THE EVENT. WITH THE TROUGH GOING A LITTLE NEGATIVE TILT...THE FRONT MAY SLOW BEFORE CLEARING OUT SATURDAY AND HAVE EXTENDED POPS A BIT TO ADDRESS. SUNDAY AND MONDAY SHOULD BE VERY NICE UNDER SURFACE HIGH PRESSURE. WE SHOULD SEE HIGHS IN THE 70S SATURDAY THROUGH MONDAY WITH LOWS IN THE 50S CWA WIDE. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... AS OF 05Z...THE -RA FROM EARLIER TONIGHT HAS MOSTLY PUSHED OFFSHORE...AND THE MID LEVEL CLOUDS SHOULD GRADUALLY THIN OVERNIGHT AS THE UPPER TROUGH MOVES OVERHEAD AND OFF THE COAST. SURFACE OBS INDICATE FOG IS DEVELOPING OVER THE CENTRAL CAROLINAS WHERE THE WINDS HAVE GONE CALM AND THE MID LEVEL CIGS ARE NO MORE. THEREFORE...HAVE ADDED TEMPO IFR VSBYS FOR KLBT/KFLO EARLY THIS MORNING. THIS TREND FOLLOWS SOME OF THE LATEST HRRR RUNS SHOWING FOG/STRATUS EXPANDING INLAND AFTER 09Z. STILL THINK THE DEVELOPING LOW OFF THE SOUTHEAST COAST WILL KEEP WINDS AT THE COASTAL TERMINALS STRONG ENOUGH TO PREVENT ANY FOG...BUT SOME TEMPO IFR CIGS CANNOT BE RULED OUT BY DAYBREAK. WILL KEEP SCT 500 FT STRATUS AT THE COAST ATTM. DURING THE DAY... DRIER AIR BEHIND THE UPPER TROUGH WILL ALLOW VFR CONDITIONS TO DEVELOP AND PERSIST FOR THE REST OF THE TAF PERIOD. EXPECT NORTHEAST WINDS AOB 10 KT DURING THE DAY...BECOMING LIGHT/VRB AFTER 00Z WED. EXTENDED OUTLOOK...VFR CONDITIONS WILL PREVAIL THROUGH FRI. CHANCE OF SHOWERS/MVFR LATE FRI/EARLY SAT WITH A STRONG COLD FRONT. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1045 PM MONDAY...CURRENTLY A BROAD LOW EXTENDS OFF THE GA-FL COASTS FROM NE GULF OF MEXICO. MODELS CONTINUE TO PAINT A DEVELOPING SFC LOW OFFSHORE AND EAST OF THE GA COAST BY DAYBREAK TUE. THIS WILL RESULT IN A SFC PRESSURE PATTERN AND GRADIENT ACROSS THE ILM WATERS THAT WILL YIELD NE 10-20 KT OVERNIGHT INTO DAYLIGHT TUE. THE HIGHER END OF THIS SCALE TO OCCUR CLOSER TO THE LOW...OVER THE ILM SC WATERS. SIGNIFICANT SEAS IN THE 2 TO 4 FT RANGE...EXCEPT UP TO 5 FT OVER THE SOUTHERNMOST ILM SC WATERS. FOUR TO 6 SECOND PERIOD...WIND DRIVEN WAVES TO DOMINATE THE SIGNIFICANT SEAS. PREVIOUS DISCUSSION.............................................. AS OF 745 PM MONDAY...COASTAL TROF OR FRONT TO REMAIN OVER THE OFFSHORE WATERS JUST EAST OF THE COASTAL WATERS OVERNIGHT. WEAK SFC LOW TO MOVE OFF THE GA-FL COAST EARLY THIS EVENING...AND MOVE ENE ALONG THIS BOUNDARY OVERNIGHT STAYING OFFSHORE TO A POSITION OF 140NM SOUTH OF CAPE FEAR BY DAYBREAK TUE. THE LOW WILL STRENGTHEN-SOME AND HAVE AN EFFECT ON THE LOCAL WINDS...ESPECIALLY ACROSS THE ILM SC WATERS. FOR NOW WILL FORECAST A SOLID 10-15 KT BUT MAY INCREASE TO A SOLID 15 KT OR A 15-20 KT RANGE FOR THE ILM SC WATERS. SIGNIFICANT SEAS WILL RANGE IN THE 2 TO 4 FT...HIGHEST OFF CAPE FEAR AND OFF FROM THE MOUTH OF WINYAH BAY. FIVE FOOTERS ARE A POSSIBILITY OVER THE SOUTHERNMOST WATERS...WILL MONITOR. LOOKING AT 4 TO 5 SECONDS FOR AVERAGE PERIODS. SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... AS OF 300 PM MONDAY...LOW PRESSURE WILL DEEPEN TUESDAY MORNING OFF THE GEORGIA COAST ALONG AN OLD FRONT. AS THIS LOW MOVES AWAY FROM THE COASTLINE WEAK HIGH PRESSURE WILL BUILD SOUTHWARD ACROSS THE CAROLINA COASTAL WATERS...REMAINING IN PLACE THROUGH WEDNESDAY NIGHT. THIS MEANS AFTER THE INITIAL SURGE OF NORTH-NORTHEASTERLY WINDS TUESDAY...CONDITIONS SHOULD IMPROVE MARKEDLY FOR THE REMAINDER OF THE PERIOD. THE STRONGEST WINDS...NC AROUND 15 KNOTS WITH GUSTS TO 18-20 KNOTS...ARE EXPECTED TO BEGIN DIMINISHING AROUND SUNSET TUESDAY EVENING. LIGHTER NORTHEASTERLY WINDS SHOULD DOMINATE THROUGH THE PERIOD...EXCEPT WEDNESDAY AFTERNOON WHEN A WEAK SEABREEZE SHOULD TURN WIND DIRECTIONS MORE SOUTHEASTERLY. SEAS 3-4 FEET TUESDAY WILL DIMINISH TO AROUND 2 FEET. AMONG THE VARIOUS MODEL SOLUTIONS THE 12Z GFS LOOKS THE BEST FOLLOWED BY THE 00Z ECMWF. LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 300 PM MONDAY...VERY LIGHT WIND FIELDS THURSDAY WILL GIVE WAY TO STRONGER WINDS FRIDAY AND SATURDAY. SURFACE HIGH PRESSURE WILL BE WEAKENING THURSDAY AND EAST WINDS WILL TURN TO SOUTHEAST LATE. WIND SPEEDS WILL BE TEN KNOTS OR LESS. BY MIDDAY FRIDAY...THE SOUTHERLY FLOW WILL PICK UP AHEAD OF THE FRONT TO 10-15 KNOTS. THE FRONT SHOULD CROSS THE WATERS EARLY SATURDAY WITH A NORTHWEST FLOW OF 10-15 KNOTS ENSUING. SIGNIFICANT SEAS WILL BE 1-3 FEET THURSDAY AND MOST OF THE DAY FRIDAY. SATURDAY THE RANGE WILL INCREASE TO 2-4 FEET WITH THE HIGHER SEAS ACROSS THE OUTER WATERS. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...DCH SHORT TERM...TRA LONG TERM...SHK AVIATION...BJR/SRP
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1254 PM CDT TUE SEP 30 2014 .UPDATE... ISSUED AT 1254 PM CDT TUE SEP 30 2014 UPDATED POPS THIS AFTERNOON AND EVENING BASED ON LATEST RADAR AND 15 UTC HRRR TRYING TO CONVEY THE ANTICIPATED BREAKS IN ACTIVITY BETWEEN THE CURRENT WAVE LIFTING THROUGH CENTRAL AND NORTHWEST ND AT THIS TIME...AND THE NEXT WAVE EXPECTED TO PUSH INTO THE SOUTH CENTRAL BY MID AFTERNOON. DID ADD A MENTION OF SEVERE ACROSS THE FAR SOUTH CENTRAL 21-00 UTC ASSOCIATED WITH THE STRONG SHEAR AND LOW LEVEL HELICITY. THE LATEST HRRR IS NOT A STRONG WITH LATE AFTERNOON AND EARLY CONVECTION OVER THE JAMES RIVER VALLEY. UPDATE ISSUED AT 1033 AM CDT TUE SEP 30 2014 MADE A FEW ADJUSTMENTS TO POPS BASED ON LATEST MESOSCALE MODELS. OTHERWISE NO SIGNIFICANT CHANGES AT THIS TIME. STRONG STACKED LOW PRESSURE SYSTEM OVER SOUTHWEST NORTH DAKOTA WILL LIFT INTO NORTH DAKOTA BY LATE THIS AFTERNOON/EARLY EVENING. VERY STRONG SHEAR/LOW LEVEL HELICITY WILL EXIST OVER SOUTH CENTRAL NORTH DAKOTA THIS AFTERNOON AND EARLY EVENING. LATEST MESOSCALE MODELS INDICATE LOW TOPPED CONVECTION MOVING INTO THE FAR SOUTH CENTRAL AROUND 20/21Z AND LIFTING THROUGH THE SOUTH CENTRAL AND JAMES RIVER VALLEY THROUGH EARLY EVENING. WITH THE STRENGTH OF THIS SYSTEM THERE WILL BE A RISK OF SEVERE WEATHER GENERALLY ALONG AND SOUTH OF THE INTERSTATE FROM AROUND THE MISSOURI RIVER EAST INTO THE JAMES RIVER VALLEY. THE MAIN THREAT WILL BE DAMAGING WINDS...DUE TO THE EXPECTED FAST STORM MOTION...AND WEAK TORNADOES DUE TO THE STRONG SHEAR AND LOW LEVEL HELICITY. WILL FRESHEN UP PRODUCTS INCLUDING THE HWO WITH LATEST THINKING. UPDATE ISSUED AT 628 AM CDT TUE SEP 30 2014 WELL DEFINED CLOSED UPPER LOW CENTERED NEAR RAPID CITY IS LIFTING NORTH. SHOWERS AND SCATTERED THUNDERSTORMS WILL OVERSPREAD SOUTH CENTRAL NORTH DAKOTA THIS MORNING. CURRENT TRENDS HAVE THE RAIN ARRIVING IN BISMARCK AROUND 9 AM CDT. ADJUSTED POPS ACCORDINGLY FOR THIS. ALSO FOG NOT AS WIDESPREAD AS EARLIER THOUGHT. CONFINED THE FOG MAINLY TO THE SOUTHWEST. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 330 AM CDT TUE SEP 30 2014 CURRENTLY...A LARGE SURFACE LOW AND AN UPPER LEVEL LOW WERE OVER THE WESTERN NE/SD BORDER. THIS STACKED SYSTEM WAS NEAR THE BASE OF A LARGE UPPER LEVEL TROUGH EXTENDING FROM ALASKA SOUTHEASTWARD ACROSS THE ROCKIES INTO THE WESTERN PLAINS. AN UPPER LEVEL ENERGY IMPULSE MOVING NORTHWARD FROM THE BASE OF THE TROUGH WAS PROGGED TO MOVE FROM SOUTH CENTRAL/WESTERN TO NORTH CENTRAL/WESTERN NORTH DAKOTA BY DAYBREAK TODAY. THIS IS COINCIDENT WITH AN AREA OF SHOWERS AND THUNDERSTORMS LIFTING NORTHERLY THROUGH THE DAKOTAS. AFTER DAYBREAK THE THE STACKED LOW PRESSURE SYSTEM IS FORECAST TO BE CENTERED OVER SOUTHWESTERN SOUTH DAKOTA...THEN LIFT NORTHEASTWARD INTO SOUTH CENTRAL NORTH DAKOTA THIS AFTERNOON...FINALLY EXITING INTO MANITOBA BY DAYBREAK ON WEDNESDAY MORNING. MODELS ARE IN GOOD AGREEMENT WITH THIS SCENARIO...AND WITH SHOWERS AND SCATTERED THUNDERSTORMS CONTINUING TO DEVELOP AND EXPAND ACROSS ALL OF WESTERN AND CENTRAL NORTH DAKOTA TODAY AND TONIGHT. HIGHEST RAINFALL AMOUNTS WITH THIS SYSTEM - INCLUDING WHAT HAS ALREADY FALLEN BEFORE SUNRISE TODAY - POINT TO THE WESTERN THIRD OF THE STATE...WHERE AN INCH OR MORE OF RAINFALL IS FORECAST. CENTRAL NORTH DAKOTA CAN EXPECT A WIDESPREAD AREA OF 1/2 INCH TO 3/4 OF AN INCH...WITH 1/3 TO 1/2 INCH OF RAIN IN THE JAMES RIVER VALLEY. THE RAIN SHOWERS SHOULD DISSIPATE FROM SOUTH TO NORTH LATE TONIGHT AS THE SYSTEM LIFTS INTO MANITOBA. LOOK FOR HIGH TEMPERATURES TODAY FROM THE MID 50S TO LOWER 60S...WITH LOWS TONIGHT FROM THE MID 40S TO MID 50S. .LONG TERM...(WEDNESDAY THROUGH MONDAY) ISSUED AT 330 AM CDT TUE SEP 30 2014 AFTER THE SHORT TERM UPPER LOW KICKS OUT THERE IS A SECOND SHORTWAVE IN THE NORTHERN STREAM THAT WILL MOVE FROM WESTERN CANADA INTO THE NORTHERN PLAINS THURSDAY AND THURSDAY NIGHT BRINGING A SHOT OF COOLER AIR BEHIND A COLD FRONT. HAVE ADDED SCATTERED THUNDERSTORMS THURSDAY AFTERNOON AS THE COLD FRONT ENTERS THE REGION AND GFS/ECMWF MODELS SHOW SOME CAPE IS AVAILABLE TO SUPPORT CONVECTION. THE WEEKEND GENERALLY LOOKS DRY WITH A SLOW MODERATION OF TEMPERATURES INTO THE 60S BY EARLY NEXT WEEK AS A BROAD RIDGE ALOFT CENTERED OVER THE WESTERN US EXTENDS TO THE NORTHERN PLAINS. STILL DO NOT SEE A HARD FREEZE FOR THOSE AREAS THAT HAVE NOT SEEN ONE...CENTRAL AND EASTERN NORTH DAKOTA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z WEDNESDAY AFTERNOON) ISSUED AT 1254 PM CDT TUE SEP 30 2014 WIDESPREAD MVFR-IFR CEILINGS AND VISIBILITIES THIS AFTERNOON AND TONIGHT WITH A ROUND OF SHOWERS CURRENTLY LIFTING THROUGH NORTHWEST AND CENTRAL NORTH DAKOTA...AND ANOTHER ROUND EXPECTED TO MOVE INTO THE SOUTH CENTRAL BY MID AFTERNOON AND LIFT NORTH NORTHEAST THROUGH CENTRAL NORTH DAKOTA THIS EVENING. WINDS WILL BE VARIABLE AS THE SURFACE LIFTS THROUGH CENTRAL NORTH DAKOTA. DO EXPECT SOME IMPROVEMENT TO VFR CONDITIONS FROM SOUTHWEST TO NORTHEAST BY MID TO LATE MORNING WEDNESDAY. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...JV LONG TERM...WAA AVIATION...TWH
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
205 PM EDT TUE SEP 30 2014 .SYNOPSIS... MID/UPPER LEVEL DISTURBANCE SWINGS SOUTHEAST...BRUSHES AREA THIS AFTERNOON/EVENING. WEAK HIGH PRESSURE/LIGHT WINDS WEDNESDAY INTO EARLY THURSDAY STRONG COLD FRONT FRIDAY. MUCH COOLER WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 130 PM UPDATE... SHOWERS CURRENTLY PROGRESSING EASTWARD ACROSS THE FAR NW ZONES AT THIS TIME. THESE ARE PART OF THE LARGER LINE OF SHRA TO THE NORTH ACROSS WESTERN PA AND NW OHIO. WHILE THAT PORTION OF THE LINE IS MOVING EAST QUICKER...THE SOUTHERN PART OF THE LINE AFFECTING OUR AREA IS SLOWER AS TO BE EXPECTED. THIS TREND SHOULD CONTINUE. MAY BE MORE REDEVELOPMENT ACROSS SE OHIO LATER THIS AFTERNOON. 1030 AM UPDATE... FIRST LINE OF CONVECTION WITH SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ALREADY NEARING PERRY COUNTY AT THIS TIME. RAMPED UP POPS TO THE LIKELY CATEGORY FOR THOSE LOCATIONS NEAR OUR NORTHWEST FORECAST AREA BORDER FROM PERRY COUNTY OVER TOWARDS MORGAN AND WASH COUNTIES IN OHIO FOR THE NEXT 1-3 HOURS AS IT QUICKLY MOVES EAST. PREVIOUS DISCUSSION... PATCHES OF CLOUDS STILL OVER THE MOUNTAINS AT 07Z...OTHERWISE VALLEY FOG PREVAILS. WATER VAPOR IMAGERY DEPICTS MID/UPPER TROF OVER LAKE HURON AND MICHIGAN DROPPING SOUTHEAST. ASSOCIATED COLD FRONT/WIND SHIFT WAS APPROACHING TOL AND STILL NORTH OF IND. AS MENTIONED YESTERDAY...THE MAIN COOLING ALOFT TODAY WILL BE NORTH OF OUR CWA. FOR EXAMPLE...00Z NAM HAS 500 MB TEMP AT PBZ COOLING ABOUT 5C TODAY...WHILE CKB ONLY ABOUT A DEG C. SO TIMING THE POPS...AND HOW FAR SOUTH TO MENTION PCPN FOR THIS AFTERNOON AND TONIGHT IS ONE CHALLENGE. AFTER DIGESTING THE MODELS...SEE NO REASON TO CHANGE THE SLIGHT CHANCE POP REACHING AS FAR SOUTH AS HTS-CRW VCNTY FOR THIS EVENING. THIS IS A BIT FURTHER SOUTH THAN MOST 00Z MODEL SOLUTIONS. FURTHER NNE...HAVE POPS MAXING OUT AROUND 40 TO 50 PCT FOR N CNTRL WV FROM 21Z TODAY TO 01Z WEDNESDAY. DRY AIR SOUTH OF THAT DISTURBANCE FOR TODAY. RAP SOLUTION TRIES TO EVEN LOWER DEW POINTS INTO THE 40S. MAYBE ACROSS HIGH TERRAIN LIKE BKW...BUT DID NOT GO THAT LOW IN THE WESTERN LOWLANDS. MAIN PUSH BEHIND FRONT IS INTO SOUTHEAST OHIO...BEFORE 925 MB WINDS QUICKLY VEER TO EAST OR DIMINISH TO CALM. THINKING LOW STRATUS WILL FORM TONIGHT IN SE OHIO BEHIND FRONT. FURTHER SOUTH IN THE COAL FIELDS OF WV...WAS THINKING JUST THE USUAL DIURNAL LATE NIGHT FOG. FURTHER NORTH...LINGERING CLOUDS MAY HINDER OR DELAY THE FOG FORMATION AROUND CKB AND EKN. HTS-CRW CORRIDOR IS A TOUGH CALL BETWEEN ALL 3 FOR LATE TONIGHT...PATCHES OF CLOUDS LINGERING OVERNIGHT...STRATUS FORMATION...OR SURFACE BASED FOG FORMING. OVERALL KEPT MINIMUM TEMPERATURE ON THE HIGH SIDE OF GFS MOS GUIDANCE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... UPPER LEVEL LOW WILL BE HEADING EAST OUT TO SEA TO START THE SHORT TERM PERIOD. IN THE WAKE OF THIS LOW...ANTICIPATE LOTS OF LOW STRATUS WEDNESDAY MORNING...GRADUALLY BREAKING UP THROUGH THE DAY. ONE EXCEPTION WILL BE FAR SOUTHERN CWA WHERE DO NOT EXPECT THESE CLOUDS. WITH THE EXPECTED CLOUDS...ALSO LOWERED HIGHS ON WEDNESDAY SEVERAL DEGREES IN SE OHIO. BLENDED BIAS CORRECTED MET INTO PREVIOUS FORECAST. HAVE A LITTLE TRAILING VORT MAX COMING THROUGH WEDNESDAY INTO WEDNESDAY NIGHT SO HAVE SOME SLIGHT CHANCE TO CHANCE POPS IN THE NORTHERN MOUNTAINS...BUT DRY ELSEWHERE. WEAK SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING PASSES THURSDAY WITH A WARMER...SUNNY DAY. AGAIN BLENDED IN BIAS CORRECTED MET. BY THURSDAY NIGHT...CLOUDS INCREASING AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. FOR LOWS WEDNESDAY AND THURSDAY NIGHTS...BLENDED IN BIAS CORRECTED CONSENSUS GUIDANCE. && .LONG TERM /FRIDAY THROUGH MONDAY/... L/W TROUGH SETTLES IN OVER THE AREA THIS PERIOD. RAIN IS MOST LIKELY FRI AS LEAD SRN STREAM S/W TROUGH CROSSES JUST OUT AHEAD OF SFC COLD FRONT...WHICH IS DRIVEN BY MID STREAM S/W PIVOTING THROUGH THE LOWER GREAT LAKES AND OHIO VALLEY FRI...DRIVING THE SFC COLD FRONT THROUGH LATE FRI AFTERNOON AND EVENING. STRONG FLOW...FORCING...LAST MINUTE LOW LEVEL MOISTURE CONVERGENCE AND LATE DAY TIMING SHOULD SUPPORT THE CHANCE FOR THUNDER...ALTHOUGH A MITIGATING FACTOR IS THE LEAD SRN STREAM S/W...WHICH BRINGS CLOUDS AND RAIN ACROSS EARLIER IN THE DAY. A HIGH OF MAINLY PACIFIC ORIGIN BUILDS IN BEHIND THE FRONT INITIALLY...BRINGING ABOUT A FAIR...COOL WEEKEND. A REINFORCING UPPER LEVEL S/W TROUGH AND SFC FRONT CROSS MON...WITH A CHANCE FOR SHOWERS...AND THEN EVEN COOLER WEATHER EARLY NEXT WEEK. BLENDED IN GFS BASED GUIDANCE FOR HIGHS FRI AND THEN MAINLY WPC FOR LOWS AND HIGHS BEYOND THAT...MOST CHANGES TO LOWER VALUES BUT NOT BY MUCH. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... GENERALLY VFR CONDITIONS BEING EXPERIENCED THIS AFTERNOON. A LINE OF SHOWERS CURRENTLY PUSHING SLOWLY ACROSS SE OHIO INTO THE PANHANDLE OF WV SHOULD CONTINUE SLOWLY EASTWARD THIS AFTERNOON...MAINLY NEAR AND NORTH OF US HWY 50. BRIEF MVFR/IFR VIS IS POSSIBLE UNDERNEATH A HEAVIER SHOWER BUT AGAIN...VFR CONDITIONS SHOULD BE PREVALENT OTHERWISE. EXPECT LOWER MVFR/IFR CEILINGS TO MOVE SOUTH INTO SOUTHEAST OHIO 00Z TO 06Z WEDNESDAY...BEHIND THE FRONT CURRENTLY JUST TO THE NORTHWEST. A GOOD DEAL OF UNCERTAINTY EXISTS MAINLY FOR THE CENTRAL WV LOWLANDS WITH EXACTLY HOW FAR EAST AND SOUTH IT PROGRESSES...WITH LOW STRATUS AND/OR FOG POSSIBLE IN THIS GENERAL AREA. THINKING MORE DIURNAL FOG WILL FORM ACROSS SOUTHERN WEST VIRGINIA BY 06Z WEDNESDAY. EXPECT SLOWLY IMPROVING CONDITIONS DURING THE MORNING HOURS BTWN 15Z-18Z. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: COVERAGE OF SHOWERS MAY BE MORE THAN FORECAST IN THE PKB-CKB-EKN VCNTY. ARRIVAL OF LOWER STRATUS CEILING INTO SOUTHEAST OHIO AND MID OHIO VALLEY AROUND PKB MAY BE FASTER THAN FORECAST. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H M M M M CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z WEDNESDAY... BRIEF IFR POSSIBLE IN FAST MOVING SHOWERS AND/OR THUNDERSTORMS FRIDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KTB/MZ NEAR TERM...KTB/50 SHORT TERM...MZ LONG TERM...TRM AVIATION...50
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1050 AM EDT TUE SEP 30 2014 .SYNOPSIS... MID/UPPER LEVEL DISTURBANCE SWINGS SOUTHEAST...BRUSHES AREA THIS AFTERNOON/EVENING. WEAK HIGH PRESSURE/LIGHT WINDS WEDNESDAY INTO EARLY THURSDAY STRONG COLD FRONT FRIDAY. MUCH COOLER WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... 1030 AM UPDATE... FIRST LINE OF CONVECTION WITH SHOWERS AND A FEW EMBEDDED THUNDERSTORMS ALREADY NEARING PERRY COUNTY AT THIS TIME. RAMPED UP POPS TO THE LIKELY CATEGORY FOR THOSE LOCATIONS NEAR OUR NORTHWEST FORECAST AREA BORDER FROM PERRY COUNTY OVER TOWARDS MORGAN AND WASH COUNTIES IN OHIO FOR THE NEXT 1-3 HOURS AS IT QUICKLY MOVES EAST. PREVIOUS DISCUSSION... PATCHES OF CLOUDS STILL OVER THE MOUNTAINS AT 07Z...OTHERWISE VALLEY FOG PREVAILS. WATER VAPOR IMAGERY DEPICTS MID/UPPER TROF OVER LAKE HURON AND MICHIGAN DROPPING SOUTHEAST. ASSOCIATED COLD FRONT/WIND SHIFT WAS APPROACHING TOL AND STILL NORTH OF IND. AS MENTIONED YESTERDAY...THE MAIN COOLING ALOFT TODAY WILL BE NORTH OF OUR CWA. FOR EXAMPLE...00Z NAM HAS 500 MB TEMP AT PBZ COOLING ABOUT 5C TODAY...WHILE CKB ONLY ABOUT A DEG C. SO TIMING THE POPS...AND HOW FAR SOUTH TO MENTION PCPN FOR THIS AFTERNOON AND TONIGHT IS ONE CHALLENGE. AFTER DIGESTING THE MODELS...SEE NO REASON TO CHANGE THE SLIGHT CHANCE POP REACHING AS FAR SOUTH AS HTS-CRW VCNTY FOR THIS EVENING. THIS IS A BIT FURTHER SOUTH THAN MOST 00Z MODEL SOLUTIONS. FURTHER NNE...HAVE POPS MAXING OUT AROUND 40 TO 50 PCT FOR N CNTRL WV FROM 21Z TODAY TO 01Z WEDNESDAY. DRY AIR SOUTH OF THAT DISTURBANCE FOR TODAY. RAP SOLUTION TRIES TO EVEN LOWER DEW POINTS INTO THE 40S. MAYBE ACROSS HIGH TERRAIN LIKE BKW...BUT DID NOT GO THAT LOW IN THE WESTERN LOWLANDS. MAIN PUSH BEHIND FRONT IS INTO SOUTHEAST OHIO...BEFORE 925 MB WINDS QUICKLY VEER TO EAST OR DIMINISH TO CALM. THINKING LOW STRATUS WILL FORM TONIGHT IN SE OHIO BEHIND FRONT. FURTHER SOUTH IN THE COAL FIELDS OF WV...WAS THINKING JUST THE USUAL DIURNAL LATE NIGHT FOG. FURTHER NORTH...LINGERING CLOUDS MAY HINDER OR DELAY THE FOG FORMATION AROUND CKB AND EKN. HTS-CRW CORRIDOR IS A TOUGH CALL BETWEEN ALL 3 FOR LATE TONIGHT...PATCHES OF CLOUDS LINGERING OVERNIGHT...STRATUS FORMATION...OR SURFACE BASED FOG FORMING. OVERALL KEPT MINIMUM TEMPERATURE ON THE HIGH SIDE OF GFS MOS GUIDANCE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... UPPER LEVEL LOW WILL BE HEADING EAST OUT TO SEA TO START THE SHORT TERM PERIOD. IN THE WAKE OF THIS LOW...ANTICIPATE LOTS OF LOW STRATUS WEDNESDAY MORNING...GRADUALLY BREAKING UP THROUGH THE DAY. ONE EXCEPTION WILL BE FAR SOUTHERN CWA WHERE DO NOT EXPECT THESE CLOUDS. WITH THE EXPECTED CLOUDS...ALSO LOWERED HIGHS ON WEDNESDAY SEVERAL DEGREES IN SE OHIO. BLENDED BIAS CORRECTED MET INTO PREVIOUS FORECAST. HAVE A LITTLE TRAILING VORT MAX COMING THROUGH WEDNESDAY INTO WEDNESDAY NIGHT SO HAVE SOME SLIGHT CHANCE TO CHANCE POPS IN THE NORTHERN MOUNTAINS...BUT DRY ELSEWHERE. WEAK SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING PASSES THURSDAY WITH A WARMER...SUNNY DAY. AGAIN BLENDED IN BIAS CORRECTED MET. BY THURSDAY NIGHT...CLOUDS INCREASING AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. FOR LOWS WEDNESDAY AND THURSDAY NIGHTS...BLENDED IN BIAS CORRECTED CONSENSUS GUIDANCE. && .LONG TERM /FRIDAY THROUGH MONDAY/... L/W TROUGH SETTLES IN OVER THE AREA THIS PERIOD. RAIN IS MOST LIKELY FRI AS LEAD SRN STREAM S/W TROUGH CROSSES JUST OUT AHEAD OF SFC COLD FRONT...WHICH IS DRIVEN BY MID STREAM S/W PIVOTING THROUGH THE LOWER GREAT LAKES AND OHIO VALLEY FRI...DRIVING THE SFC COLD FRONT THROUGH LATE FRI AFTERNOON AND EVENING. STRONG FLOW...FORCING...LAST MINUTE LOW LEVEL MOISTURE CONVERGENCE AND LATE DAY TIMING SHOULD SUPPORT THE CHANCE FOR THUNDER...ALTHOUGH A MITIGATING FACTOR IS THE LEAD SRN STREAM S/W...WHICH BRINGS CLOUDS AND RAIN ACROSS EARLIER IN THE DAY. A HIGH OF MAINLY PACIFIC ORIGIN BUILDS IN BEHIND THE FRONT INITIALLY...BRINGING ABOUT A FAIR...COOL WEEKEND. A REINFORCING UPPER LEVEL S/W TROUGH AND SFC FRONT CROSS MON...WITH A CHANCE FOR SHOWERS...AND THEN EVEN COOLER WEATHER EARLY NEXT WEEK. BLENDED IN GFS BASED GUIDANCE FOR HIGHS FRI AND THEN MAINLY WPC FOR LOWS AND HIGHS BEYOND THAT...MOST CHANGES TO LOWER VALUES BUT NOT BY MUCH. && .AVIATION /12Z TUESDAY THROUGH SATURDAY/... EXPECTING THE RIVER VALLEY FOG TO BE THE SLOWEST TO EVAPORATE E AND S OF CRW IN THE SOUTHERN WEST VIRGINIA COAL FIELDS...BUT SHOULD BE GONE BY 14Z. SCATTERED TO BROKEN CLOUDS AT 3 TO 5 THSD FT FORMING 14Z TO 17Z OVER SOUTHEAST OHIO AND NORTHERN WEST VIRGINIA...PLUS THE CENTRAL WV MOUNTAINS. HAVE SCATTERED SHOWERS REACHING INTO UNI-PKB-CKB-KEN CORRIDOR 18Z TO 21Z...THEN LINGERING IN NORTHERN/CENTRAL WV 00Z TO 06Z. COULD NOT RULE OUT A MINIMAL THUNDERSTORM. AN ISOLATED CELL COULD REACH HTS-CRW CORRIDOR 22Z TUESDAY TO 03Z WEDNESDAY. EXPECT LOWER CEILINGS TO BE MOVING SOUTH INTO SOUTHEAST OHIO 00Z TO 06Z WEDNESDAY...WITH 1 THSD FT BKN TO OVC POSSIBLE AND VSBY NEAR 5 MILES IN HAZE. HOW FAR EAST AND SOUTH THAT ADVECTS IS DIFFICULT TO FIGURE...WITH 925 MB FLOW QUICKLY TURNING TO EAST BEFORE 06Z WEDNESDAY. CRW A TOUGH CALL BETWEEN STRATUS AND SURFACE BASED FOG FORMING 06Z TO 12Z WEDNESDAY. THINKING MORE DIURNAL FOG WILL FORM ACROSS SOUTHERN WEST VIRGINIA BY 06Z WEDNESDAY. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: COVERAGE OF SHOWERS MAY BE MORE THAN FORECAST IN THE PKB-CKB-EKN VCNTY. ARRIVAL OF LOWER STRATUS CEILING INTO SOUTHEAST OHIO AND MID OHIO VALLEY AROUND PKB MAY BE FASTER THAN FORECAST. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EDT 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21 CRW CONSISTENCY L M H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY L H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 12Z WEDNESDAY... BRIEF IFR POSSIBLE IN FAST MOVING SHOWERS AND/OR THUNDERSTORMS FRIDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KTB/MZ NEAR TERM...KTB/50 SHORT TERM...MZ LONG TERM...TRM AVIATION...KTB
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
618 AM EDT TUE SEP 30 2014 .SYNOPSIS... MID/UPPER LEVEL DISTURBANCE SWINGS SOUTHEAST...BRUSHES AREA THIS AFTERNOON/EVENING. WEAK HIGH PRESSURE/LIGHT WINDS WEDNESDAY INTO EARLY THURSDAY STRONG COLD FRONT FRIDAY. MUCH COOLER WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... PATCHES OF CLOUDS STILL OVER THE MOUNTAINS AT 07Z...OTHERWISE VALLEY FOG PREVAILS. WATER VAPOR IMAGERY DEPICTS MID/UPPER TROF OVER LAKE HURON AND MICHIGAN DROPPING SOUTHEAST. ASSOCIATED COLD FRONT/WIND SHIFT WAS APPROACHING TOL AND STILL NORTH OF IND. AS MENTIONED YESTERDAY...THE MAIN COOLING ALOFT TODAY WILL BE NORTH OF OUR CWA. FOR EXAMPLE...00Z NAM HAS 500 MB TEMP AT PBZ COOLING ABOUT 5C TODAY...WHILE CKB ONLY ABOUT A DEG C. SO TIMING THE POPS...AND HOW FAR SOUTH TO MENTION PCPN FOR THIS AFTERNOON AND TONIGHT IS ONE CHALLENGE. AFTER DIGESTING THE MODELS...SEE NO REASON TO CHANGE THE SLIGHT CHANCE POP REACHING AS FAR SOUTH AS HTS-CRW VCNTY FOR THIS EVENING. THIS IS A BIT FURTHER SOUTH THAN MOST 00Z MODEL SOLUTIONS. FURTHER NNE...HAVE POPS MAXING OUT AROUND 40 TO 50 PCT FOR N CNTRL WV FROM 21Z TODAY TO 01Z WEDNESDAY. DRY AIR SOUTH OF THAT DISTURBANCE FOR TODAY. RAP SOLUTION TRIES TO EVEN LOWER DEW POINTS INTO THE 40S. MAYBE ACROSS HIGH TERRAIN LIKE BKW...BUT DID NOT GO THAT LOW IN THE WESTERN LOWLANDS. MAIN PUSH BEHIND FRONT IS INTO SOUTHEAST OHIO...BEFORE 925 MB WINDS QUICKLY VEER TO EAST OR DIMINISH TO CALM. THINKING LOW STRATUS WILL FORM TONIGHT IN SE OHIO BEHIND FRONT. FURTHER SOUTH IN THE COAL FIELDS OF WV...WAS THINKING JUST THE USUAL DIURNAL LATE NIGHT FOG. FURTHER NORTH...LINGERING CLOUDS MAY HINDER OR DELAY THE FOG FORMATION AROUND CKB AND EKN. HTS-CRW CORRIDOR IS A TOUGH CALL BETWEEN ALL 3 FOR LATE TONIGHT...PATCHES OF CLOUDS LINGERING OVERNIGHT...STRATUS FORMATION...OR SURFACE BASED FOG FORMING. OVERALL KEPT MINIMUM TEMPERATURE ON THE HIGH SIDE OF GFS MOS GUIDANCE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... UPPER LEVEL LOW WILL BE HEADING EAST OUT TO SEA TO START THE SHORT TERM PERIOD. IN THE WAKE OF THIS LOW...ANTICIPATE LOTS OF LOW STRATUS WEDNESDAY MORNING...GRADUALLY BREAKING UP THROUGH THE DAY. ONE EXCEPTION WILL BE FAR SOUTHERN CWA WHERE DO NOT EXPECT THESE CLOUDS. WITH THE EXPECTED CLOUDS...ALSO LOWERED HIGHS ON WEDNESDAY SEVERAL DEGREES IN SE OHIO. BLENDED BIAS CORRECTED MET INTO PREVIOUS FORECAST. HAVE A LITTLE TRAILING VORT MAX COMING THROUGH WEDNESDAY INTO WEDNESDAY NIGHT SO HAVE SOME SLIGHT CHANCE TO CHANCE POPS IN THE NORTHERN MOUNTAINS...BUT DRY ELSEWHERE. WEAK SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING PASSES THURSDAY WITH A WARMER...SUNNY DAY. AGAIN BLENDED IN BIAS CORRECTED MET. BY THURSDAY NIGHT...CLOUDS INCREASING AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. FOR LOWS WEDNESDAY AND THURSDAY NIGHTS...BLENDED IN BIAS CORRECTED CONSENSUS GUIDANCE. && .LONG TERM /FRIDAY THROUGH MONDAY/... L/W TROUGH SETTLES IN OVER THE AREA THIS PERIOD. RAIN IS MOST LIKELY FRI AS LEAD SRN STREAM S/W TROUGH CROSSES JUST OUT AHEAD OF SFC COLD FRONT...WHICH IS DRIVEN BY MID STREAM S/W PIVOTING THROUGH THE LOWER GREAT LAKES AND OHIO VALLEY FRI...DRIVING THE SFC COLD FRONT THROUGH LATE FRI AFTERNOON AND EVENING. STRONG FLOW...FORCING...LAST MINUTE LOW LEVEL MOISTURE CONVERGENCE AND LATE DAY TIMING SHOULD SUPPORT THE CHANCE FOR THUNDER...ALTHOUGH A MITIGATING FACTOR IS THE LEAD SRN STREAM S/W...WHICH BRINGS CLOUDS AND RAIN ACROSS EARLIER IN THE DAY. A HIGH OF MAINLY PACIFIC ORIGIN BUILDS IN BEHIND THE FRONT INITIALLY...BRINGING ABOUT A FAIR...COOL WEEKEND. A REINFORCING UPPER LEVEL S/W TROUGH AND SFC FRONT CROSS MON...WITH A CHANCE FOR SHOWERS...AND THEN EVEN COOLER WEATHER EARLY NEXT WEEK. BLENDED IN GFS BASED GUIDANCE FOR HIGHS FRI AND THEN MAINLY WPC FOR LOWS AND HIGHS BEYOND THAT...MOST CHANGES TO LOWER VALUES BUT NOT BY MUCH. && .AVIATION /10Z TUESDAY THROUGH SATURDAY/... EXPECTING THE RIVER VALLEY FOG TO BE THE SLOWEST TO EVAPORATE E AND S OF CRW IN THE SOUTHERN WEST VIRGINIA COAL FIELDS...BUT SHOULD BE GONE BY 14Z. SCATTERED TO BROKEN CLOUDS AT 3 TO 5 THSD FT FORMING 14Z TO 17Z OVER SOUTHEAST OHIO AND NORTHERN WEST VIRGINIA...PLUS THE CENTRAL WV MOUNTAINS. HAVE SCATTERED SHOWERS REACHING INTO UNI-PKB-CKB-KEN CORRIDOR 18Z TO 21Z...THEN LINGERING IN NORTHERN/CENTRAL WV 00Z TO 06Z. COULD NOT RULE OUT A MINIMAL THUNDERSTORM. AN ISOLATED CELL COULD REACH HTS-CRW CORRIDOR 22Z TUESDAY TO 03Z WEDNESDAY. EXPECT LOWER CEILINGS TO BE MOVING SOUTH INTO SOUTHEAST OHIO 00Z TO 06Z WEDNESDAY...WITH 1 THSD FT BKN TO OVC POSSIBLE AND VSBY NEAR 5 MILES IN HAZE. HOW FAR EAST AND SOUTH THAT ADVECTS IS DIFFICULT TO FIGURE...WITH 925 MB FLOW QUICKLY TURNING TO EAST BEFORE 06Z WEDNESDAY. CRW A TOUGH CALL BETWEEN STRATUS AND SURFACE BASED FOG FORMING 06Z TO 12Z WEDNESDAY. THINKING MORE DIURNAL FOG WILL FORM ACROSS SOUTHERN WEST VIRGINIA BY 06Z WEDNESDAY. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: COVERAGE OF SHOWERS MAY BE MORE THAN FORECAST IN THE PKB-CKB-EKN VCNTY. ARRIVAL OF LOWER STRATUS CEILING INTO SOUTHEAST OHIO AND MID OHIO VALLEY AROUND PKB MAY BE FASTER THAN FORECAST. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE TUE 09/30/14 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15 CRW CONSISTENCY L L L L L L L M H H H H HTS CONSISTENCY L L L L L M H H H H H H BKW CONSISTENCY L L L L L H H H H H H H EKN CONSISTENCY L L L L L L H H H H H H PKB CONSISTENCY L L L L L H H H H H H H CKB CONSISTENCY L L L L L M H H H H H H AFTER 12Z WEDNESDAY... BRIEF IFR POSSIBLE IN FAST MOVING SHOWERS AND/OR THUNDERSTORMS FRIDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KTB/MZ NEAR TERM...KTB SHORT TERM...MZ LONG TERM...TRM AVIATION...KTB
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
348 AM EDT TUE SEP 30 2014 .SYNOPSIS... MID/UPPER LEVEL DISTURBANCE SWINGS SOUTHEAST...BRUSHES AREA THIS AFTERNOON/EVENING. WEAK HIGH PRESSURE/LIGHT WINDS WEDNESDAY INTO EARLY THURSDAY STRONG COLD FRONT FRIDAY. MUCH COOLER WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... PATCHES OF CLOUDS STILL OVER THE MOUNTAINS AT 07Z...OTHERWISE VALLEY FOG PREVAILS. WATER VAPOR IMAGERY DEPICTS MID/UPPER TROF OVER LAKE HURON AND MICHIGAN DROPPING SOUTHEAST. ASSOCIATED COLD FRONT/WIND SHIFT WAS APPROACHING TOL AND STILL NORTH OF IND. AS MENTIONED YESTERDAY...THE MAIN COOLING ALOFT TODAY WILL BE NORTH OF OUR CWA. FOR EXAMPLE...00Z NAM HAS 500 MB TEMP AT PBZ COOLING ABOUT 5C TODAY...WHILE CKB ONLY ABOUT A DEG C. SO TIMING THE POPS...AND HOW FAR SOUTH TO MENTION PCPN FOR THIS AFTERNOON AND TONIGHT IS ONE CHALLENGE. AFTER DIGESTING THE MODELS...SEE NO REASON TO CHANGE THE SLIGHT CHANCE POP REACHING AS FAR SOUTH AS HTS-CRW VCNTY FOR THIS EVENING. THIS IS A BIT FURTHER SOUTH THAN MOST 00Z MODEL SOLUTIONS. FURTHER NNE...HAVE POPS MAXING OUT AROUND 40 PCT FOR N CNTRL WV FROM 22Z TODAY TO 01Z WEDNESDAY. DRY AIR SOUTH OF THAT DISTURBANCE FOR TODAY. RAP SOLUTION TRIES TO EVEN LOWER DEW POINTS INTO THE 40S. MAYBE ACROSS HIGH TERRAIN LIKE BKW...BUT DID NOT GO THAT LOW IN THE WESTERN LOWLANDS. MAIN PUSH BEHIND FRONT IS INTO SOUTHEAST OHIO...BEFORE 925 MB WINDS QUICKLY VEER TO EAST OR DIMINISH TO CALM. THINKING LOW STRATUS WILL FORM TONIGHT IN SE OHIO BEHIND FRONT. FURTHER SOUTH IN THE COAL FIELDS OF WV...WAS THINKING JUST THE USUAL DIURNAL LATE NIGHT FOG. FURTHER NORTH...LINGERING CLOUDS MAY HINDER OR DELAY THE FOG FORMATION AROUND CKB AND EKN. HTS-CRW CORRIDOR IS A TOUGH CALL BETWEEN ALL 3 FOR LATE TONIGHT...PATCHES OF CLOUDS LINGERING OVERNIGHT...STRATUS FORMATION...OR SURFACE BASED FOG FORMING. OVERALL KEPT MINIMUM TEMPERATURE ON THE HIGH SIDE OF GFS MOS GUIDANCE. && .SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... UPPER LEVEL LOW WILL BE HEADING EAST OUT TO SEA TO START THE SHORT TERM PERIOD. IN THE WAKE OF THIS LOW...ANTICIPATE LOTS OF LOW STRATUS WEDNESDAY MORNING...GRADUALLY BREAKING UP THROUGH THE DAY. ONE EXCEPTION WILL BE FAR SOUTHERN CWA WHERE DO NOT EXPECT THESE CLOUDS. WITH THE EXPECTED CLOUDS...ALSO LOWERED HIGHS ON WEDNESDAY SEVERAL DEGREES IN SE OHIO. BLENDED BIAS CORRECTED MET INTO PREVIOUS FORECAST. HAVE A LITTLE TRAILING VORT MAX COMING THROUGH WEDNESDAY INTO WEDNESDAY NIGHT SO HAVE SOME SLIGHT CHANCE TO CHANCE POPS IN THE NORTHERN MOUNTAINS...BUT DRY ELSEWHERE. WEAK SURFACE HIGH PRESSURE AND UPPER LEVEL RIDGING PASSES THURSDAY WITH A WARMER...SUNNY DAY. AGAIN BLENDED IN BIAS CORRECTED MET. BY THURSDAY NIGHT...CLOUDS INCREASING AHEAD OF A COLD FRONT APPROACHING FROM THE WEST. FOR LOWS WEDNESDAY AND THURSDAY NIGHTS...BLENDED IN BIAS CORRECTED CONSENSUS GUIDANCE. && .LONG TERM /FRIDAY THROUGH MONDAY/... L/W TROUGH SETTLES IN OVER THE AREA THIS PERIOD. RAIN IS MOST LIKELY FRI AS LEAD SRN STREAM S/W TROUGH CROSSES JUST OUT AHEAD OF SFC COLD FRONT...WHICH IS DRIVEN BY MID STREAM S/W PIVOTING THROUGH THE LOWER GREAT LAKES AND OHIO VALLEY FRI...DRIVING THE SFC COLD FRONT THROUGH LATE FRI AFTERNOON AND EVENING. STRONG FLOW...FORCING...LAST MINUTE LOW LEVEL MOISTURE CONVERGENCE AND LATE DAY TIMING SHOULD SUPPORT THE CHANCE FOR THUNDER...ALTHOUGH A MITIGATING FACTOR IS THE LEAD SRN STREAM S/W...WHICH BRINGS CLOUDS AND RAIN ACROSS EARLIER IN THE DAY. A HIGH OF MAINLY PACIFIC ORIGIN BUILDS IN BEHIND THE FRONT INITIALLY...BRINGING ABOUT A FAIR...COOL WEEKEND. A REINFORCING UPPER LEVEL S/W TROUGH AND SFC FRONT CROSS MON...WITH A CHANCE FOR SHOWERS...AND THEN EVEN COOLER WEATHER EARLY NEXT WEEK. BLENDED IN GFS BASED GUIDANCE FOR HIGHS FRI AND THEN MAINLY WPC FOR LOWS AND HIGHS BEYOND THAT...MOST CHANGES TO LOWER VALUES BUT NOT BY MUCH. && .AVIATION /07Z TUESDAY THROUGH SATURDAY/... RIVER VALLEY FOG SHOULD BE COMMON THROUGH WEST VIRGINIA INTO SOUTHWEST VIRGINIA 06Z TO 12Z. DRIER AIR IN SOUTHEAST OHIO...BUT THE COOLER TEMPERATURES MAY STILL CAUSE SOME FOG THERE...BUT OF SHORTER DURATION. SCATTERED TO BROKEN CLOUDS AT 3 TO 5 THSD FT FORMING 14Z TO 17Z OVER SOUTHEAST OHIO AND NORTHERN WEST VIRGINIA...PLUS THE CENTRAL WV MOUNTAINS. HAVE SCATTERED SHOWERS REACHING INTO UNI-PKB-CKB-KEN CORRIDOR 18Z TO 21Z...THEN LINGERING IN NORTHERN/CENTRAL WV 00Z TO 06Z. COULD NOT RULE OUT A MINIMAL THUNDERSTORM. AN ISOLATED CELL COULD REACH HTS-CRW CORRIDOR 22Z TUESDAY TO 03Z WEDNESDAY. EXPECT LOWER CEILINGS TO BE MOVING SOUTH INTO SOUTHEAST OHIO 00Z TO 06Z WEDNESDAY...WITH 1 THSD FT BKN TO OVC POSSIBLE AND VSBY NEAR 5 MILES IN HAZE. HOW FAR EAST AND SOUTH THAT ADVECTS IS DIFFICULT TO FIGURE...WITH 925 MB FLOW QUICKLY TURNING TO EAST BEFORE 06Z WEDNESDAY. THINKING MORE DIURNAL FOG WILL FORM ACROSS SOUTHERN WEST VIRGINIA BY 06Z WEDNESDAY. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z WEDNESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIOS: RIVER/VALLEY FOG TIMING AND DENSITY MAY VARY OVERNIGHT. ARRIVAL OF LOWER STRATUS CEILING INTO SOUTHEAST OHIO AND MID OHIO VALLEY AROUND PKB MAY BE FASTER THAN FORECAST. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE TUE 09/30/14 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EDT 1HRLY 04 05 06 07 08 09 10 11 12 13 14 15 CRW CONSISTENCY L L L L L L L M H H H H HTS CONSISTENCY L L L L L M H H H H H H BKW CONSISTENCY L L L L L H H H H H H H EKN CONSISTENCY L L L L L L H H H H H H PKB CONSISTENCY L L L L L H H H H H H H CKB CONSISTENCY L L L L L M H H H H H H AFTER 06Z WEDNESDAY... BRIEF IFR POSSIBLE IN SHOWERS AND/OR THUNDERSTORMS FRIDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...NONE. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...KTB/MZ NEAR TERM...KTB SHORT TERM...MZ LONG TERM...TRM AVIATION...KTB
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
153 AM EDT TUE SEP 30 2014 .SYNOPSIS... A LOW OVER MICHIGAN WILL MOVE ACROSS BUFFALO TUESDAY MORNING. HIGH PRESSURE NORTH OF THE LAKES WILL SPREAD SOUTH INTO LAKE ERIE TUESDAY NIGHT THEN SHIFT OFF TO THE EAST THURSDAY. A LOW WILL MOVE THROUGH THE LAKES PULLING A STRONG COLD FRONT ACROSS THE REGION FRIDAY. HIGH PRESSURE WILL BUILD INTO UP THE OHIO VALLEY LATER SATURDAY THEN ANOTHER LOW WILL MOVE THROUGH THE LAKES MONDAY. && .NEAR TERM /THROUGH TODAY/... A BAND OF POST FRONTAL SHOWERS CONTINUES TO MOVE SOUTH ACROSS CENTRAL LOWER MICHIGAN. THE HRRR IS SHOWING THIS BAND TRYING TO FALL APART AS MID-LEVEL DRY AIR WRAPS AROUND THE SOUTH SIDE OF THE UPPER TROUGH BEFORE FILLING IN AGAIN TOWARDS MORNING AS THE TROUGH AXIS PIVOTS AROUND TO THE SOUTHEAST. STILL THINKING CHANCES ARE PRETTY GOOD FOR SEEING SHOWERS LATE TONIGHT FOR THE TOLEDO AREA AND ACROSS NRN AND NE OHIO ON TUESDAY. DURATION COULD BE FAIRLY BRIEF IN NW OHIO...LASTING FOR A MAYBE A FEW HOURS IN THE EAST BEFORE MID-LEVEL DRY AIR ARRIVES. TWEAKED MINS IN A FEW AREAS OVERNIGHT...RAISING TEMPERATURES FROM FINDLAY TO SANDUSKY BY A COUPLE DEGREES WHERE DEWPOINTS WILL BE ON THE INCREASE...BUT LIKELY AHEAD OF THE RAIN. TWEAKED A FEW OF THE COOLER SPOTS DOWN IN THE EAST (BJJ/YNG) WHERE TEMPS ARE ALREADY IN THE MID 50S. ALSO LOWERED HIGHS ON TUESDAY BY SEVERAL DEGREES IN NW OHIO AS TEMPERATURES WILL STRUGGLE TO RECOVER BEHIND THE FRONT UNLESS WE CAN GET ANY DECENT BREAKS IN THE CLOUDS. MODEL SOUNDING SUGGEST THAT WILL BE HARD TO DO WITH MOISTURE TRAPPED BELOW THE INVERSION NEAR 900MB. ORIGINAL DISCUSSION...A SHARPENING UPPER TROUGH WILL DIVE SE ACROSS LAKE ERIE TUE MORNING. THE STRONG VORT MAX WITH THIS FEATURE SHOULD PROVIDE THE FORCING TO GENERATE A BAND OF SHRA AND A FEW POSSIBLE TSRA THAT SHOULD MOVE ESE TO NEAR CLE BY 12Z TUE THEN WORK ACROSS THE EAST INTO TUE AFTERNOON. COLDER TEMPS ALOFT WILL LIKELY LEAD TO SOME LAKE ENHANCEMENT FOR TUE AFTERNOON THAT WILL KEEP THE THREAT FOR SHRA GOING IN THE EAST UNTIL AROUND MIDNIGHT TUE NIGHT. QPF WITH THIS EVENT LOOKS TO RANGE FROM A TENTH OF AN INCH OR LESS IN THE SW TO A QUARTER TO A THIRD OF AN INCH IN THE NE. TEMPS TONIGHT SHOULD BE A LITTLE WARMER DUE TO INCREASING CLOUDS THEN TEMPS ON TUE WILL BE COOLER ALSO DUE TO THE CLOUDS ALONG WITH THE SHRA AND COOLER AIR BEING PULLED INTO THE AREA FROM THE NW. && .SHORT TERM /TONIGHT THROUGH THURSDAY NIGHT/... AFTER THE SHRA THREAT TUE EVE...CLOUDS SHOULD BE DECREASING SOME THUS HELPING FOR A COLDER NIGHT WITH LOWS 47 TO 52 FOR MOST OF THE AREA. AN ISOLATED SHRA COULD STILL OCCUR IN NW PA WED DUE TO UPPER TROUGHING...OTHERWISE HIGH PRESSURE RIDGED SOUTH INTO THE AREA SHOULD PROVIDE DRY CONDITIONS UNTIL THU NIGHT. THE HIGH WILL BE SHIFTING OFF TO THE EAST LATER WED THRU THU SO TEMPS WILL MODERATE A LITTLE WARMER ON WED AND MORE SO ON THU. STRONGER STORMS LOOK POSSIBLE WITH THE COLD FRONT ON FRI BUT SHOULD STAY WEST OF THE AREA THU NIGHT. && .LONG TERM /FRIDAY THROUGH MONDAY/... A SIGNIFICANT PATTERN CHANGE WILL BE OCCURRING DURING THIS PERIOD TO COOLER AND WETTER CONDITIONS. A FRONT WILL BE MOVING THROUGH ON FRIDAY. THE BEST CHANCE FOR ANY PRECIPITATION WILL BE IN THE MORNING WITH A DRY SLOT FOR MUCH OF THE AFTERNOON. FOR FRIDAY NIGHT INTO SATURDAY NIGHT THE MODEL DIFFER ON THE QPF AND THE UPPER AIR PATTERN. THE ECMWF HAS A CLOSED LOW MOVING ACROSS THE AREA ON SATURDAY WHILE THE GFS AND CANADIAN MODEL HAVE A DRYING NORTHWEST FLOW...WITH THE BEST CHANCE OF SHOWERS OVER NE OH AND NW PA...MORE LAKE INDUCED WITH THE LAKE AND 850 MB TEMPERATURE DIFFERENCE NEAR 18C. THE GFS AND CANADIAN SOLUTION SEEM BETTER. NONE THE LESS IT WILL BE COOL ON SATURDAY WITH HIGHS IN THE 50S...AT LEAST 10 DEGREES BELOW NORMAL IF NOT A LITTLE MORE. ANOTHER FRONT WILL BE MOVING THROUGH LATE SUNDAY NIGHT INTO MONDAY WITH A CHANCE OF SHOWERS. SOME QUESTION ABOUT THE TEMPERATURE FORECAST AS THE ECMWF TRIES TO KEEP THINGS COOL. STAYED CLOSE TO WPC GUIDANCE BECAUSE OF THE UNCERTAINTY. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... THE FORWARD PROGRESS OF THE SHOWERS WITH THE COLD FRONT WILL LIKELY SLOW THIS MORNING AS A WEAK WAVE BEGINS TO DEVELOP ON THE FRONT. THERE IS CURRENTLY A FAIR AMOUNT OF IFR CEILINGS FOLLOWING THE FRONT...BUT AS THE SYSTEM SLOWS THE LOWER CEILINGS AND VISIBILITIES WILL TAKE UNTIL LATE MORNING OR AFTERNOON TO REACH KCAK AND KYNG. CEILINGS WILL PROBABLY IMPROVE TO MVFR THIS AFTERNOON ACROSS NW OHIO BUT STRATUS AND IFR CEILINGS WILL LIKELY LINGER OR REDEVELOP ACROSS NE OH/NW PA TUESDAY EVENING. .OUTLOOK...NON VFR THROUGH WEDNESDAY MORNING AND AGAIN ON FRIDAY. NON VFR LIKELY SATURDAY ACROSS NE OH/NW PA. && .MARINE... THE SOMEWHAT LIGHT WINDS ON THE LAKE WILL LAST THROUGH MID WEEK BEFORE CONDITIONS CHANGE DRAMATICALLY. A WEAK FRONT WILL MOVE ACROSS THE LAKE LATE TONIGHT. THE WINDS WILL SHIFT TO THE NORTHWEST. THE WINDS WILL BE LESS THAN 15 KNOTS AS THE COLD ADVECTION IS VERY WEAK ON TUESDAY. HOWEVER...SOME SHOWERS...DRIZZLE AND LOW CLOUDS WILL OCCUR. WEDNESDAY THROUGH THURSDAY LOOKS LIKE THE LAST GOOD DAYS ON THE LAKE FOR AWHILE. A THREAT OF MUCH STRONGER WINDS WILL OCCUR LATE THURSDAY NIGHT THROUGH SATURDAY AS A STRONG COLD FRONT WILL MOVE ACROSS THE LAKE ON FRIDAY. SOME THUNDERSTORMS MAY OCCUR AHEAD OF THE FRONT...SO SPECIAL MARINE WARNINGS MAY BE NEEDED. THE MAIN THREAT FOR A SMALL CRAFT ADVISORY WILL BE FRIDAY INTO SATURDAY AFTER THE FRONTAL PASSAGE. IT IS POSSIBLE THAT THE WIND SPEEDS COULD EVEN GET STRONG ENOUGH AHEAD OF THE FRONT TO WARRANT A SMALL CRAFT ADVISORY. SOME QUESTION HOW STRONG THE WINDS WILL BE AFTER THE FRONTAL PASSAGE. THE GFS MODEL HAS WINDS APPROACHING GALE FORCE WHILE THE ECMWF AND CANADIAN ARE MORE IN THE 15 TO 25 KNOT RANGE. AT THIS TIME LEANING TOWARD THE LIGHTER WINDS...AS THE GFS SEEMS TO OVERDO THE WINDS AT TIMES. THE THREAT FOR A SMALL CRAFT ADVISORY WILL CONTINUE THROUGH SATURDAY MORNING. SOME QUESTION HOW STRONG THE WINDS WILL BE SATURDAY AFTERNOON INTO SUNDAY. THE GFS AND CANADIAN MODELS TRIES TO BUILD A RIDGE OVER THE LAKE SATURDAY AFTERNOON WHILE THE ECMWF HAS A TROF AND THAT WOULD MEAN THE THREAT FOR SMALL CRAFT ADVISORY CONDITIONS WOULD CONTINUE INTO SUNDAY. NONE THE LESS WHICH EVER MODEL IS CORRECT THE LAKE WILL BE CHOPPY ESPECIALLY EAST OF CLEVELAND LATE SATURDAY INTO SUNDAY. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...ADAMS NEAR TERM...ADAMS/KEC SHORT TERM...ADAMS LONG TERM...KIELTYKA AVIATION...KOSARIK MARINE...KIELTYKA
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
231 AM EDT TUE SEP 30 2014 .SYNOPSIS... A WEAK COLD FRONT AND AN UPPER LEVEL DISTURBANCE WILL MOVE OUT OF THE GREAT LAKES AND BRING AN INCREASE IN CLOUDS ALONG WITH SOME SHOWERS OR THUNDERSTORMS TUESDAY INTO WEDNESDAY. A STRONGER COLD FRONT WILL PUSH EAST INTO THE COMMONWEALTH LATE FRIDAY NIGHT OR SATURDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A LONE SHOWER COULD AFFECT A FEW SPOTS ALONG THE MASON DIXON LINE IN YORK AND ADAMS CO BTWN 04Z-07Z. SHIELD OF MID AND HIGH LVL CLOUDS OVER EASTERN PA SHOULD PUSH EAST OF THE AREA BY ARND 06Z...AS SHORTWAVE AND ASSOC WAA ALOFT SHIFT EAST OF THE STATE. CENTRAL PA WILL BE IN BTWN SHORTWAVES TONIGHT...ONE DEPARTING THE E COAST AND NEXT SHORTWAVE DIVING ACROSS THE GRT LKS. LG SCALE SUBSIDENCE BTWN THESE SYSTEMS SHOULD ENSURE A DRY FCST OVERNIGHT. MCLEAR SKIES AND A CALM WIND WILL PROMOTE AREAS OF LATE NIGHT VALLEY FOG. LATEST SREF AND RAP OUTPUT SUGGEST...UNLIKE MANY RECENT NIGHTS...SOME OF THE FOG COULD AFFECT EVEN THE LOWER SUSQ VALLEY. DWPTS IN THE 50S SHOULD TRANSLATE TO ANOTHER MILD NIGHT FOR LATE SEPT...WITH LOWS MOSTLY IN THE L/M 50S. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... A POTENT UPPER SHORTWAVE/LOW OVR THE GRT LKS WILL DIVE SE ACROSS PA ON TUESDAY. DECREASING STABILITY UNDER THE COLD POOL ALOFT WILL HELP SUPPORT THE DEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS. ENSEMBLES AND OPERATIONAL GUIDANCE INDICATE THAT CAPE WILL BE MODEST...BUT FORECAST TOTAL-TOTALS IN EXCESS OF 50 ARE USUALLY A GOOD INDICATOR FOR THE POTENTIAL OF SOME LOW TOPPED CONVECTION. BASIN AVERAGE RAINFALL IS EXPECTED TO BE LIGHT...ON THE ORDER OF 0.10 OF AN INCH OR LESS...BUT AMOUNTS COULD BE SLIGHTLY HEAVIER...0.15 TO 0.25 OF AN INCH...ACROSS THE FAR NW TUESDAY AFTERNOON AND EVENING. MAX TEMPS TUESDAY ARE EXPECTED TO BE JUST A FEW DEG COOLER AND IN THE LOWER TO MID 70S. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... PROGRESSIVE UPPER LOW/COMPACT TROF AXIS OVER THE NERN U.S. AT THE START OF THE PERIOD IS FORECAST TO LIFT OUT BY THE END OF THE WEEK...AS UPPER RIDGE REBUILDS ACROSS THE REGION INTO THE EARLY PART OF THE WEEKEND. A SECOND...MUCH STRONGER AND EXPANSIVE UPPER TROF AXIS EXTENDING SWD FROM AN UPPER LOW ANCHORED OVER NRN ONTARIO IS FORECAST TO SWEEP ACROSS THE EASTERN U.S. OVER THE WEEKEND. CLOUDIER AND MORE UNSETTLED WEATHER THAN RECENT DAYS IS EXPECTED TO ACCOMPANY THE FIRST TROF WED...HOWEVER THE SYSTEM IS SOMEWHAT MOISTURE-LIMITED AND SIGNIFICANT PCPN IS NOT EXPECTED. TEMPS ON WED HOWEVER WILL BE COOLER THAN RECENT DAYS. WARMER WEATHER MAKES A BRIEF RETURN THUR...FRI AND EARLY SAT AS THE UPPER RIDGE REBUILDS....WITH MAXES AND MINS AT LEAST SEVERAL DEGREES ABOVE CLIMO NORMALS. THE ARRIVAL OF THE SECOND TROF WILL SUPPORT A STRONG COLD FRONT WITH DEEPER CONNECTIONS TO THE GOMEX AND THE ATLANTIC OCEAN...THUS POTENTIAL FOR MORE WIDESPREAD AND HEAVIER RAINFALL. PASSAGE OF THE FRONT WILL ALSO BRING NOTICEABLY COOLER TEMPS TO THE REGION FOR SUNDAY INTO MONDAY. A SHORT WAVE WITHIN THE THEN EXPECTED CYCLONIC FLOW OVER THE REGION WILL BRING ANOTHER FRONTAL SYSTEM TO THE REGION WITH AN INCREASED CHANCE OF SHOWERS FOR THE END OF THE PERIOD. && .AVIATION /06Z TUESDAY THROUGH 06Z WEDNESDAY/... CLR SKIES/LGT WINDS AGAIN SUPPORTING VALLEY FOG FORMATION ACRS CENTRAL PA. HIGHEST CONFIDENCE IN IFR OR BLW AT BFD/IPT/LNS (PERSISTENCE) FOLLOWED BY AOO/UNV. MDT HAS YET TO REALLY GET INTO THE FOG OVER THE LAST SEVERAL DAYS AND WILL CAP VSBY AT 3-5SM. DEWPT DEPRESSION AT JST SUGGEST FOG IS UNLIKELY ALTHOUGH DID SHOW SCT015 GROUP TWD DAYBREAK. FOG WILL GIVE WAY TO VFR FOR THE MORNING HOURS...AHEAD OF COMPACT UPPER LEVEL LOW AND WEAK COLD FRONT FCST TO SHIFT SEWD FROM THE GRT LKS ACRS PA LATER TODAY INTO TNGT. MODEL GUIDANCE IS SUPPORTIVE OF VCSH/-SHRA MENTION AT ALL SITES FROM THIS AFTN INTO EARLY TNGT ALONG WITH A GENERAL LOWERING TREND IN CIGS/VSBYS. ARRIVAL OF COOLING ALOFT ASSOCD WITH UPPER LOW FAVORABLY TIMED WITH DAYTIME HEATING SHOULD SUPPORT ISOLD-SCT TSTM DEVELOPMENT...FOCUSING ALONG/AHEAD OF SFC COLD FRONT. THE COOL TEMPS ALOFT WILL FAVOR HAIL AS THE PRIMARY TSTM HAZARD. OUTLOOK /WEDNESDAY THROUGH SATURDAY/... WED...UPPER LOW WILL BE SLOW TO MOVE NEWD THEREFORE CHC OF SHOWERS WILL CONTINUE ON WED. SOME LOW CIGS PSBL AS WELL. THU...LOW CIGS LKLY EARLY...AND COULD PERSIST THRU MUCH OF THE DAY OR REFORM THU NGT DUE TO HIGH PRES WEDGE/MARITIME FLOW E OF THE APPLCHNS. FRI...SHOWERS AND THUNDERSTORMS LKLY ASSOCD WITH WELL-DEFINED GUSTY COLD FROPA. LLWS LKLY DUE TO STG SLY WINDS AHEAD OF THE COLD FRONT. SAT...AM SHOWERS ERN AREAS. BREEZY WITH IMPROVING CONDITIONS E OF THE MTNS DUE TO WLY DOWNSLOPE. ISOLD SHOWERS AND LOCAL MVFR POSSIBLE OVER N/WRN AREAS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...DEVOIR/FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...STEINBUGL
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1225 AM EDT TUE SEP 30 2014 .SYNOPSIS... A WEAK COLD FRONT AND AN UPPER LEVEL DISTURBANCE WILL MOVE OUT OF THE GREAT LAKES AND BRING AN INCREASE IN CLOUDS ALONG WITH SOME SHOWERS OR THUNDERSTORMS TUESDAY INTO WEDNESDAY. A STRONGER COLD FRONT WILL PUSH EAST INTO THE COMMONWEALTH LATE FRIDAY NIGHT OR SATURDAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A LONE SHOWER COULD AFFECT A FEW SPOTS ALONG THE MASON DIXON LINE IN YORK AND ADAMS CO BTWN 04Z-07Z. SHIELD OF MID AND HIGH LVL CLOUDS OVER EASTERN PA SHOULD PUSH EAST OF THE AREA BY ARND 06Z...AS SHORTWAVE AND ASSOC WAA ALOFT SHIFT EAST OF THE STATE. CENTRAL PA WILL BE IN BTWN SHORTWAVES TONIGHT...ONE DEPARTING THE E COAST AND NEXT SHORTWAVE DIVING ACROSS THE GRT LKS. LG SCALE SUBSIDENCE BTWN THESE SYSTEMS SHOULD ENSURE A DRY FCST OVERNIGHT. MCLEAR SKIES AND A CALM WIND WILL PROMOTE AREAS OF LATE NIGHT VALLEY FOG. LATEST SREF AND RAP OUTPUT SUGGEST...UNLIKE MANY RECENT NIGHTS...SOME OF THE FOG COULD AFFECT EVEN THE LOWER SUSQ VALLEY. DWPTS IN THE 50S SHOULD TRANSLATE TO ANOTHER MILD NIGHT FOR LATE SEPT...WITH LOWS MOSTLY IN THE L/M 50S. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/... A POTENT UPPER SHORTWAVE/LOW OVR THE GRT LKS WILL DIVE SE ACROSS PA ON TUESDAY. DECREASING STABILITY UNDER THE COLD POOL ALOFT WILL HELP SUPPORT THE DEVELOPMENT OF SCATTERED SHOWERS AND THUNDERSTORMS. ENSEMBLES AND OPERATIONAL GUIDANCE INDICATE THAT CAPE WILL BE MODEST...BUT FORECAST TOTAL-TOTALS IN EXCESS OF 50 ARE USUALLY A GOOD INDICATOR FOR THE POTENTIAL OF SOME LOW TOPPED CONVECTION. BASIN AVERAGE RAINFALL IS EXPECTED TO BE LIGHT...ON THE ORDER OF 0.10 OF AN INCH OR LESS...BUT AMOUNTS COULD BE SLIGHTLY HEAVIER...0.15 TO 0.25 OF AN INCH...ACROSS THE FAR NW TUESDAY AFTERNOON AND EVENING. MAX TEMPS TUESDAY ARE EXPECTED TO BE JUST A FEW DEG COOLER AND IN THE LOWER TO MID 70S. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... PROGRESSIVE UPPER LOW/COMPACT TROF AXIS OVER THE NERN U.S. AT THE START OF THE PERIOD IS FORECAST TO LIFT OUT BY THE END OF THE WEEK...AS UPPER RIDGE REBUILDS ACROSS THE REGION INTO THE EARLY PART OF THE WEEKEND. A SECOND...MUCH STRONGER AND EXPANSIVE UPPER TROF AXIS EXTENDING SWD FROM AN UPPER LOW ANCHORED OVER NRN ONTARIO IS FORECAST TO SWEEP ACROSS THE EASTERN U.S. OVER THE WEEKEND. CLOUDIER AND MORE UNSETTLED WEATHER THAN RECENT DAYS IS EXPECTED TO ACCOMPANY THE FIRST TROF WED...HOWEVER THE SYSTEM IS SOMEWHAT MOISTURE-LIMITED AND SIGNIFICANT PCPN IS NOT EXPECTED. TEMPS ON WED HOWEVER WILL BE COOLER THAN RECENT DAYS. WARMER WEATHER MAKES A BRIEF RETURN THUR...FRI AND EARLY SAT AS THE UPPER RIDGE REBUILDS....WITH MAXES AND MINS AT LEAST SEVERAL DEGREES ABOVE CLIMO NORMALS. THE ARRIVAL OF THE SECOND TROF WILL SUPPORT A STRONG COLD FRONT WITH DEEPER CONNECTIONS TO THE GOMEX AND THE ATLANTIC OCEAN...THUS POTENTIAL FOR MORE WIDESPREAD AND HEAVIER RAINFALL. PASSAGE OF THE FRONT WILL ALSO BRING NOTICEABLY COOLER TEMPS TO THE REGION FOR SUNDAY INTO MONDAY. A SHORT WAVE WITHIN THE THEN EXPECTED CYCLONIC FLOW OVER THE REGION WILL BRING ANOTHER FRONTAL SYSTEM TO THE REGION WITH AN INCREASED CHANCE OF SHOWERS FOR THE END OF THE PERIOD. && .AVIATION /06Z TUESDAY THROUGH SATURDAY/... FOG ALREADY FORMING...ADJUSTMENTS MADE TO 03Z TAFS. EARLIER DISCUSSION BELOW. CLOUDS WILL CONTINUE TO THIN OVERNIGHT. DID HIT THE FOG A LITTLE HARDER THAN IN THE 18Z TAF PACKAGE...ESPECIALLY WITH HIGHER DEWPOINTS THIS EVENING THAN IN RECENT DAYS. THERE WAS LITTLE FOG LAST NIGHT...AS MID AND HI CLDS MOVED IN OVERNIGHT. PERHAPS A FEW SHOWERS ACROSS THE WEST ON TUE. WED...AN UPPER TROUGH/LOW DROPPING OUT OF THE GR LAKES INTO THE LOCAL AREA WILL BRING SCT RAIN SHOWERS AND EVEN SOME THUNDERSTORMS. LOW CIGS PROBABLE AT NIGHT. OUTLOOK /THU THROUGH SAT/... THU...LOW CIGS COULD LINGER MUCH OF THE DAY AS HIGH PRESSURE TO THE EAST PROVIDES AN EAST-SOUTHEAST MARITIME FLOW. FRI...SHOWERS AND THUNDERSTORMS PSBL ASSOC WITH GUSTY FROPA. SAT...BREEZY WITH IMPROVING CONDITIONS. SHOWERS AND LOCAL MVFR POSSIBLE OVER NWRN AREAS. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...LA CORTE NEAR TERM...DEVOIR/FITZGERALD SHORT TERM...FITZGERALD/LA CORTE LONG TERM...LAMBERT/GARTNER AVIATION...MARTIN
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
402 PM CDT TUE SEP 30 2014 .SHORT TERM... /Tonight and Wednesday/ Isolated showers have been affecting the Big County this afternoon, embedded within the mid-level moist axis streaming across the Lone Star State from southwest to northeast. The RAP Mesoanalysis indicates a narrow axis of MLCAPE values approaching 1500 J/kg across the western counties this afternoon, but even the cu development as been rather limited, suggesting a pretty strong cap. We are seeing a bit more vertical development in the cu field over the Trans-Pecos area, however, and any convection that develops may drift into the southwest zones. Thus, the slight chance PoPs were retained this evening, mainly west of a line from Ozona, to Robert Lee, to Miller Creek Reservoir. Winds will be a few mph stronger than what was observed last night and, combined with the increasing low-level moisture, should support min temps in the mid to upper 60s. On Wednesday, the thermal ridge axis will shift east, resulting in 850mb temps of 24-25C across the Big Country and Concho Valley by peak heating. With low-level adiabatic lapse rates during the afternoon hours, we should have little problem warming into the lower 90s across much of the area. These warm temperatures may strain the cap to its breaking point by late afternoon, so the mention of showers and thunderstorms was retained after 20z (3 PM). Coverage is expected to remain very limited, but any storms that develop could be strong. .LONG TERM... /Wednesday night through Monday/ Afternoon water vapor imagery shows a strengthening trough progressing southeast across the Inter-mountain West, upper-level moisture streaming northeast across west central Texas from Tropical Depression Rachel, and a shortwave trough lifting northeast across the Dakotas. A dryline observed in surface observations extends south through the Texas Panhandle, with a few showers developing ahead of this feature. Ahead of this dryline, southeasterly surface winds continue to advect moisture into the region from the Gulf of Mexico. The trend in the model solutions the past few days has been to delay the arrival of a cold front. This trend has continued today with the GFS and ECMWF trending towards the NAM model. Convective temperatures are expected to be reached tomorrow evening. With sufficient moisture/good instability in place, shower and thunderstorm development will be possible, mainly north and west of a line from San Angelo to Baird. Forecast soundings show SBCAPEs in excess of 2000 J/kg, around 20-25 Kts of 0-6km shear, and T/TD spreads around 30 degrees F. With this type of environment, a few strong thunderstorms will be possible. With the arrival of the upper trough Thursday, a cold front will cross the area during the day. For Thursday, moisture, instability, and shear will increase ahead of the cold front, with forecast soundings indicating convective temperatures being reached, and a higher potential for strong thunderstorms/possibly a few severe/ if frontal timing in the models are correct. Friday will feature cooler temperatures, with highs near 80 degrees. Another disturbance will cross the Central Plains this weekend sending a weak cold front south. This front will stall across the area on Sunday, with increasing surface moisture likely south of the front. However, moisture return looks insufficient for shower development at this time. Overall confidence is moderate in rain chances Wednesday/Thursday. && .PRELIMINARY POINT TEMPS/POPS... Abilene 69 92 72 92 56 / 10 10 20 20 5 San Angelo 69 93 73 89 57 / 10 5 10 20 10 Junction 66 91 73 90 60 / 5 5 5 20 20 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ Johnson/60
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1241 PM CDT TUE SEP 30 2014 .DISCUSSION... SEE AVIATION FOR 18Z TAF DISCUSSION. && .AVIATION... SHOWERS BEGINNING TO FORM INLAND OF MATAGORDA BAY AND WILL EXPAND EASTWARD THROUGH THE AFTERNOON. HAVE CARRIED A VCTS FOR LBX AND THE METRO AREA TAF SITES. COVERAGE SHOULD BE VERY LOW BUT BOTH THE TXTECH WRF AND 12Z HRRR RUNS FOCUS ACTIVITY NEAR THE METRO AREA FOR A BRIEF PERIOD THIS AFTERNOON. CONVECTION SHOULD END QUICKLY WITH THE LOSS OF DAYTIME HEATING. OTHER CONCERN TONIGHT WILL BE POTENTIAL FOR MVFR CIGS AS ONSHORE FLOW STRENGTHENS ACROSS THE REGION. AGAIN THE NAM SEEMS TO BE TOO AGGRESSIVE WHILE THE GFS IS LIKELY UNDERESTIMATING LOW LEVEL MOISTURE. WILL CARRY TEMPO FOR NOW AND ALLOW LATER SHIFTS TO REEVALUATE THIS EVENING. 38 && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 72 92 76 92 68 / 10 10 10 30 50 HOUSTON (IAH) 73 90 77 91 72 / 10 20 10 30 60 GALVESTON (GLS) 78 84 79 87 77 / 10 20 10 20 60 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ DISCUSSION...45 AVIATION/MARINE...38
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
ISSUED BY NATIONAL WEATHER SERVICE NEW ORLEANS LA 1232 PM CDT TUE SEP 30 2014 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION... A FEW SHOWERS HAVE DEVELOPED OVER THE FORECAST AREA. HAVE MAINTAINED VCSH FOR KHRL...STILL THINK THAT THE MAJORITY OF THE SHOWERS WILL STAY NORTH OF KBRO AND KMFE. EXPECT MVFR TO VFR CONDITIONS TO CONTINUE THROUGH THE TAF FORECAST PERIOD. && .PREV DISCUSSION... /ISSUED 630 AM CDT TUE SEP 30 2014/ SHORT TERM /NOW THROUGH THROUGH WEDNESDAY/...LATEST SATELLITE AND WATER VAPOR OBSERVATIONS SHOW RIDGE MIGRATING EASTWARD AS A STRONG LOW PRESSURE MOVES ACROSS THE ROCKIES INTO THE UPPER MIDWEST TODAY. THIS TROUGH WILL PUSH THE HIGH PRESSURE EAST AND DEEPENS THE LEE SIDE TROUGH ACROSS WESTERN TEXAS EXTENDING INTO THE CWA GRADUALLY INCREASING WINDS BY THE END OF THE SHORT TERM PERIOD. IR SATELLITE IMAGERY SHOWS THE WEAK SURFACE LOW PRESSURE CENTER OVER SOUTHERN HIDALGO COUNTY AND UNDERNEATH DEEP LOW LEVEL MOISTURE IS DEPICTED OVER THE AREA WITH 00Z KBRO SOUNDING SHOWING DEEP MOISTURE CONCENTRATED UP TO 800 MB. PRECIPITABLE WATERS ONLY REACH 1.72 INCHES AND THAT IS DUE TO THE DRY MID LEVEL AIR MOVING IN WITH THE NORTHWEST FLOW ALOFT. AS OF 8Z...RADAR SHOWS SOME ISOLATED SHOWER DEVELOPMENT FAVORING NORTHERN KENEDY COUNTY AND EASTERN HIDALGO AND CAMERON AND IT IS MAINLY RAP RAP AROUND THE WEAK LOW/MCV. THE CONVECTION PATTERN WILL CONTINUE THROUGH THE EARLY MORNING HOURS AND MOVE INTO BROOKS COUNTY BY MID DAY AS THE WEAK LOW MOVES FURTHER INLAND BEFORE IT GETS TAKEN BY THE MID TO UPPER FLOW ASSOCIATED WITH THE RIDGE. THIS WILL MAINTAIN SHOWERS ALONG THE COAST AND THE GULF WATERS LATE TODAY INTO WED. LEFT INHERITED 10 PERCENT AS AN ISOLATED SHOWER CAN NOT BE RULED OUT. THE WINDS WILL BE LIGHT AND VARIABLE FOR THE MOST PART TODAY WITH PATCHY FOG AND LOW CIGS THROUGH THE EARLY MORNING HOURS. TEMPERATURES WILL REACH THE MID TO UPPER 80S AND CLOSE TO 90S ALONG THE RIVER OVER THE WESTERN COUNTIES. TONIGHT THE DRY AIR WILL LOWER THE CHANCE OF MORE SHOWERS ACROSS THE AREA SO LEAN TOWARDS 10 POPS THROUGH THE NIGHT. AS THE TROUGH OVER THE PACIFIC NORTHWEST DIGS SOUTH WEDNESDAY...THE PRESSURE GRADIENT STRENGTHENS A BIT RETURNING SOUTHEAST FLOW ACROSS THE CWA ALLOWING FOR THAT WEAK LOW TO DISSIPATE. SE WINDS WILL INCREASE ESPECIALLY ALONG THE COAST WITH MORE ABUNDANT SUNSHINE EXPECTED. LOW CHANCE OF RAIN AND LOW AMOUNT OF CLOUD COVER WILL ALLOW FOR HIGH TEMPS TO RETURN TO THE 90S ACROSS MOST LOCATIONS IN THE CWA WITH THE EXCEPTION ALONG THE COAST. LOW CHANCES OF RAIN WILL REMAIN OVER THE GULF WATERS AS DRY AIR GRADUALLY DIMINISHES ANY ADDITIONAL DEVELOPMENT OVER THE AREA. TODAY DUE TO THE LIGHT TO VARIABLE WINDS AND ABUNDANT MOISTURE IN PLACE LINGERING AROUND THE AREA WILL ALLOW FOR FAVORABLE CONDITIONS FOR PATCHY GROUND FOG TO DEVELOP. VISIBILITIES WILL IMPROVE WITH DAY TIME HEATING IN THE MORNING HOUR. LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...500MB TROUGH ACROSS THE WESTERN UNITED STATES WEDNESDAY WILL MOVE EASTWARD ACROSS THE CENTRAL U.S. THURSDAY BRINGING A WEAK COLD FRONT INTO CENTRAL TEXAS THURS AFTERNOON. LOW TO MID LEVEL MOISTURE WILL POOL ALONG AND AHEAD OF THE FRONT THURS NIGHT INTO FRIDAY AS THE FRONT MOVES INTO THE RIO GRANDE VALLEY FRI AFTERNOON. THIS WILL PROVIDE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE AREA LATE THURSDAY INTO FRIDAY. RAIN CHANCES WILL LINGER ACROSS THE RGV FRI NIGHT THROUGH SAT NIGHT AS THE FRONT MOVES INTO NORTHEAST MEXICO AND STALLS AND MOISTURE CONTINUES TO POOL ACROSS NORTHERN TAMAULIAPAS. DRIER AND SLIGHTLY COOLER AIR IS EXPECTED TO FILTER INTO SOUTH TX THROUGH THE WEEKEND BEFORE THE SURFACE RIDGE ACROSS EAST TX SATURDAY MOVES EASTWARD INTO EARLY NEXT WEEK. MARINE... NOW THROUGH WEDNESDAY...THE WINDS AND SEAS WILL REMAIN LIGHT TO MODERATE AS THE WEAK LOW KEEPS SPINNING OVER THE AREA PRODUCING ERRATIC WINDS BETWEEN 10 T 15 KNOTS. THIS LOW IS HELPING PRODUCE ISOLATED SHOWERS AT THIS TIME AND DO EXPECT THE SAME PATTERN TO CONTINUE TODAY AND IMPROVE WEDNESDAY. THE SEAS WILL REMAIN LOW THROUGH THE PERIOD WITH NO SCA BUT A SCEC IS POSSIBLE WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WED NIGHT INTO THURSDAY BEFORE A WEAK COLD FRONT MOVES THROUGH THE LOWER TEXAS COAST FRIDAY. WINDS WILL SHIFT TO THE NORTH AND NORTHEAST FRI AFTERNOON AS A RESULT. THE PRESSURE GRADIENT WILL WEAKEN ACROSS THE WESTERN GULF OF MEXICO SATURDAY ALLOWING WINDS TO BECOME LIGHT FROM THE NORTHEAST. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 51/51
AREA FORECAST DISCUSSION...UPDATED
NWS LUBBOCK TX
1231 PM CDT TUE SEP 30 2014 .AVIATION... VFR CONDITIONS WILL STAY IN PLACE AT KLBB THROUGH THIS TAF CYCLE. KCDS WILL ALSO REMAIN VFR BUT HAS A CHANCE AT SEEING THUNDERSTORMS LATE THIS AFTERNOON INTO THIS EVENING. TIMING REMAINS QUESTIONABLE STILL AND UNCERTAINTY IN HOW MUCH COVERAGE IS A CONCERN AS WELL. WILL HAVE TO EVALUATE THROUGH THE AFTERNOON AND SEE IF TEMPO CAN BE REMOVED IF CONDITIONS WILL NOT BE FAVORABLE FOR STORM DEVELOPMENT. JORDAN && .PREV DISCUSSION... /ISSUED 648 AM CDT TUE SEP 30 2014/ AVIATION... BEST CURRENT INDICATIONS ARE THUNDER CHANCES DEVELOPING JUST EAST OF KLBB EARLY THIS EVENING BUT COULD BE A CLOSE CALL. BETTER CHANCE FOR THUNDER AT KCDS WERE A PROB30 GROUP WAS ADDED. VFR OTHERWISE WILL DOMINATE. LOW CHANCE FOR CG CIGS AROUND KCDS TO LOWER TO NEAR MVFR LEVELS THIS EVENING. RMCQUEEN PREV DISCUSSION... /ISSUED 356 AM CDT TUE SEP 30 2014/ SHORT TERM... A MOISTURE PLUME WAS PULLING UP INTO THE TEXAS SOUTH PLAINS REGION THIS MORNING FROM THE TROPICAL NORTHEAST PACIFIC OCEAN...WHILE AN UPPER LOW WAS SPINNING OFF INTO THE NORTHERN PLAINS. A TRAILING IMPULSE EJECTING THROUGH EAST-CENTRAL COLORADO MAY BE IN TANDEM WITH A WEAKER IMPULSE CROSSING THE MOIST PLUME OVER WEST TEXAS. ISOLATED EARLY MORNING SHOWERS WERE CROSSING THE SOUTH PLAINS...HEADING INTO THE ROLLING PLAINS LATER THIS MORNING. ALTHOUGH SIGNIFICANT LIFT IS DIFFICULT TO IDENTIFY IN THIS PATTERN...WE EXPECT TO REMAIN WITHIN THE MOIST PLUME THROUGH THIS EVENING AND SUBJECT TO AT LEAST WEAK FORCING FROM THE TRAILING SOUTHERN PORTION OF THE SYSTEM. MAJORITY OF SOLUTIONS CONTINUE TO BREAK THUNDERSTORMS OUT NEAR OR JUST EAST OF THE CENTRAL SOUTH PLAINS LATE THIS AFTERNOON AND EARLY THIS EVENING AS SURFACE CONVERGENCE TIGHTENS A DRYLINE WITH POTENTIAL SURFACE DEWPOINTS STILL IN THE LOWER OR EVEN MIDDLE 60S LYING JUST TO THE EAST. STILL SOME CONCERN OVER POSSIBLE ERRORS IN MODEL DEPICTION OF SURFACE DEWPOINT STRUCTURE...BUT OVERNIGHT TRENDS IN WRF/NAM AND RAP SEEM TO GIVE SOME CREDENCE TO THE HIGHER MOISTURE LEVELS. AND THIS WOULD GENERATE CONVECTIVE ENERGY UP TO 2500 JOULES PER KILOGRAM WITH MODEST SHEAR OF 25-30 KNOTS SUGGESTING POTENTIAL FOR A FEW HEFTY STORMS IN THIS AREA LATER TODAY. WE HAVE EDGED PREVIOUS THUNDER CHANCES SLIGHTLY BACK TO THE SOUTH AND WEST FOR LATER TODAY WHILE RETAINING BULK OF PREVIOUS FORECAST. WARM TEMPERATURES ARE EXPECTED THIS AFTERNOON....FAVORED A CONSALL/ CONSRAW ENSEMBLE APPROACH A NOTCH WARMER THAN PREVIOUS FORECAST. RMCQUEEN LONG TERM... PRECIPITATION CHANCES WILL CONTINUE ON WEDNESDAY INTO THURSDAY MORNING BEFORE AN EXTENDED DRY PERIOD DOMINATES THE WEATHER PATTERN. A COLD FRONT/RETREATING DRYLINE MAY BE THE FOCUS FOR THUNDERSTORM DEVELOPMENT ON WEDNESDAY EVENING AS ANOTHER SHORTWAVE TROUGH MOVES ACROSS THE ROCKIES. HOWEVER...THIS TROUGH IS POSITIVELY TILTED AS IT BARRELS OUT ONTO THE PLAINS BY THURSDAY. FURTHERMORE...THE TIMING OF THE TROUGH AXIS IS NOT GREAT. A BULK OF THE LARGE SCALE LIFT WILL NOT SPREAD OVER THE AREA UNTIL THURSDAY MORNING. WE WILL STILL SEE A GOOD AREA OF HEIGHT FALLS UNTIL THIS POINT. LOW LEVEL MOISTURE WILL HANG ON TO AT LEAST THE SOUTHERN ROLLING PLAINS EAST OF THE DRYLINE. BUT MID AND UPPER LEVELS WILL BE SIGNIFICANTLY DRIER THAN TODAY. THE COLD FRONT FROM THIS SHORTWAVE TROUGH WILL PUNCH THROUGH ON THURSDAY MORNING INTO THE EARLY AFTERNOON. IT WILL NOT PLOW THROUGH THE SOUTHERN ROLLING PLAINS UNTIL LATE MORNING OR EARLY AFTERNOON LEAVING POSSIBLE STORM CHANCES IN THIS AREA. AFTER THE COLD FRONT AND TROUGH ON THURSDAY...DRY NORTHWEST FLOW WILL ENTER THE REGION WITH RIDGING OVER THE WESTERN US. A WEAK SHORT WAVE ON SUNDAY WILL HAVE LITTLE CONSEQUENCE ON ANY WEATHER IMPACTS. TEMPERATURES WILL BE QUITE COOL IN THE MORNING WITH FRIDAY AND SATURDAY MORNINGS THE COOLEST DIPPING DOWN INTO THE 40S. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 80 54 83 52 71 / 10 0 0 0 0 TULIA 83 57 86 55 73 / 10 20 10 10 10 PLAINVIEW 83 58 86 55 73 / 20 20 10 10 10 LEVELLAND 84 59 86 56 75 / 10 10 10 10 10 LUBBOCK 84 60 87 56 75 / 20 20 10 10 10 DENVER CITY 85 60 87 57 77 / 10 10 10 10 10 BROWNFIELD 85 59 88 57 77 / 20 10 10 10 10 CHILDRESS 88 64 93 58 78 / 20 30 20 20 10 SPUR 86 62 91 64 81 / 20 30 10 20 10 ASPERMONT 89 67 93 69 85 / 20 20 20 20 20 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
651 AM CDT TUE SEP 30 2014 .AVIATION... /12Z TAFS/ VFR conditions will prevail across the terminals the next 24 hours. Light south winds this morning will increase 10 to 15 KT by late morning, diminishing by early evening. Isolated convection may develop late this afternoon and evening but is expected to remain west of the terminals. Stratus may develop across the Hill Country of Texas late tonight, possibly reaching the southern terminals towards daybreak. Northward extent and coverage of low clouds is still in question and will leave out of the TAF`s at this time. && .PREV DISCUSSION... /ISSUED 437 AM CDT TUE SEP 30 2014/ SHORT TERM... /Today and Tonight/ A compact upper low embedded within a broader western CONUS trough, will lift northeast across the Dakotas today. Westerly flow aloft within the base of the upper trough will induce a weak surface trough in the lee of the Rockies today, with the trough axis extending south across West Texas. Isolated to scattered convection is expected to develop along and east of this feature late this afternoon and evening. Some of this activity may reach far western sections by early evening, with the most favored area across the western Big Country counties generally west of a Throckmorton to Sweetwater line. Kept 20 POPs going across this area this evening and overnight. Convection should be more isolated farther south, but could move into far western portions of the Concho Valley and Crockett county by early evening. It is interesting to note that the RUC and some of the high resolution models develop convection farther east across the Big Country and Concho valley during peak heating. While this can`t be ruled out entirely, due to minimal CAP and a convective temperature around 90 degrees, the lack of any surface feature will preclude mentioning POPs at this time. The thermal ridge will be a bit stronger and farther east today, which will result in afternoon highs in the upper 80s to around 90 degrees. Lows tonight will be mainly in the upper 60s. LONG TERM... /Wednesday through Monday/ The main concern in the extended forecast is the potential for showers and thunderstorms in association with a cold front, followed by cooler temperatures. Highs on Wednesday will be above seasonal normals, generally in the lower to mid 90s. The NAM is indicating some convergence along a surface trough, mainly across the western Big Country, during the late afternoon/evening hours Wednesday, resulting in isolated showers and thunderstorms. Slight chance PoPs were included across the western Big Country for this time frame. An upper level trough will move across The Rockies Wednesday, then across the Plains Thursday. This will send a cold front through West Central Texas during the day Thursday, clearing the area by early evening. Isolated to scattered showers and thunderstorms will be possible along the front, mainly across the southern and eastern half of the area, where better moisture will reside. Only minor tweaks were made to the current PoPs, with the best chance across the Northwest Hill Country. Cooler, near seasonal, temperatures are forecast behind the front on Friday and Saturday, with highs in the low to mid 80s, and overnight lows in the 50s to near 60. A slow warm up will ensue Sunday through early next week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 89 69 91 71 87 / 10 10 10 20 20 San Angelo 91 69 92 72 88 / 5 10 5 10 20 Junction 88 67 91 73 90 / 0 5 5 10 20 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
648 AM CDT TUE SEP 30 2014 .AVIATION... BEST CURRENT INDICATIONS ARE THUNDER CHANCES DEVELOPING JUST EAST OF KLBB EARLY THIS EVENING BUT COULD BE A CLOSE CALL. BETTER CHANCE FOR THUNDER AT KCDS WERE A PROB30 GROUP WAS ADDED. VFR OTHERWISE WILL DOMINATE. LOW CHANCE FOR CG CIGS AROUND KCDS TO LOWER TO NEAR MVFR LEVELS THIS EVENING. RMCQUEEN && .PREV DISCUSSION... /ISSUED 356 AM CDT TUE SEP 30 2014/ SHORT TERM... A MOISTURE PLUME WAS PULLING UP INTO THE TEXAS SOUTH PLAINS REGION THIS MORNING FROM THE TROPICAL NORTHEAST PACIFIC OCEAN...WHILE AN UPPER LOW WAS SPINNING OFF INTO THE NORTHERN PLAINS. A TRAILING IMPULSE EJECTING THROUGH EAST-CENTRAL COLORADO MAY BE IN TANDEM WITH A WEAKER IMPULSE CROSSING THE MOIST PLUME OVER WEST TEXAS. ISOLATED EARLY MORNING SHOWERS WERE CROSSING THE SOUTH PLAINS...HEADING INTO THE ROLLING PLAINS LATER THIS MORNING. ALTHOUGH SIGNIFICANT LIFT IS DIFFICULT TO IDENTIFY IN THIS PATTERN...WE EXPECT TO REMAIN WITHIN THE MOIST PLUME THROUGH THIS EVENING AND SUBJECT TO AT LEAST WEAK FORCING FROM THE TRAILING SOUTHERN PORTION OF THE SYSTEM. MAJORITY OF SOLUTIONS CONTINUE TO BREAK THUNDERSTORMS OUT NEAR OR JUST EAST OF THE CENTRAL SOUTH PLAINS LATE THIS AFTERNOON AND EARLY THIS EVENING AS SURFACE CONVERGENCE TIGHTENS A DRYLINE WITH POTENTIAL SURFACE DEWPOINTS STILL IN THE LOWER OR EVEN MIDDLE 60S LYING JUST TO THE EAST. STILL SOME CONCERN OVER POSSIBLE ERRORS IN MODEL DEPICTION OF SURFACE DEWPOINT STRUCTURE...BUT OVERNIGHT TRENDS IN WRF/NAM AND RAP SEEM TO GIVE SOME CREDENCE TO THE HIGHER MOISTURE LEVELS. AND THIS WOULD GENERATE CONVECTIVE ENERGY UP TO 2500 JOULES PER KILOGRAM WITH MODEST SHEAR OF 25-30 KNOTS SUGGESTING POTENTIAL FOR A FEW HEFTY STORMS IN THIS AREA LATER TODAY. WE HAVE EDGED PREVIOUS THUNDER CHANCES SLIGHTLY BACK TO THE SOUTH AND WEST FOR LATER TODAY WHILE RETAINING BULK OF PREVIOUS FORECAST. WARM TEMPERATURES ARE EXPECTED THIS AFTERNOON....FAVORED A CONSALL/ CONSRAW ENSEMBLE APPROACH A NOTCH WARMER THAN PREVIOUS FORECAST. RMCQUEEN LONG TERM... PRECIPITATION CHANCES WILL CONTINUE ON WEDNESDAY INTO THURSDAY MORNING BEFORE AN EXTENDED DRY PERIOD DOMINATES THE WEATHER PATTERN. A COLD FRONT/RETREATING DRYLINE MAY BE THE FOCUS FOR THUNDERSTORM DEVELOPMENT ON WEDNESDAY EVENING AS ANOTHER SHORTWAVE TROUGH MOVES ACROSS THE ROCKIES. HOWEVER...THIS TROUGH IS POSITIVELY TILTED AS IT BARRELS OUT ONTO THE PLAINS BY THURSDAY. FURTHERMORE...THE TIMING OF THE TROUGH AXIS IS NOT GREAT. A BULK OF THE LARGE SCALE LIFT WILL NOT SPREAD OVER THE AREA UNTIL THURSDAY MORNING. WE WILL STILL SEE A GOOD AREA OF HEIGHT FALLS UNTIL THIS POINT. LOW LEVEL MOISTURE WILL HANG ON TO AT LEAST THE SOUTHERN ROLLING PLAINS EAST OF THE DRYLINE. BUT MID AND UPPER LEVELS WILL BE SIGNIFICANTLY DRIER THAN TODAY. THE COLD FRONT FROM THIS SHORTWAVE TROUGH WILL PUNCH THROUGH ON THURSDAY MORNING INTO THE EARLY AFTERNOON. IT WILL NOT PLOW THROUGH THE SOUTHERN ROLLING PLAINS UNTIL LATE MORNING OR EARLY AFTERNOON LEAVING POSSIBLE STORM CHANCES IN THIS AREA. AFTER THE COLD FRONT AND TROUGH ON THURSDAY...DRY NORTHWEST FLOW WILL ENTER THE REGION WITH RIDGING OVER THE WESTERN US. A WEAK SHORT WAVE ON SUNDAY WILL HAVE LITTLE CONSEQUENCE ON ANY WEATHER IMPACTS. TEMPERATURES WILL BE QUITE COOL IN THE MORNING WITH FRIDAY AND SATURDAY MORNINGS THE COOLEST DIPPING DOWN INTO THE 40S. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 80 54 83 52 71 / 10 0 0 0 0 TULIA 83 57 86 55 73 / 10 20 10 10 10 PLAINVIEW 83 58 86 55 73 / 20 20 10 10 10 LEVELLAND 84 59 86 56 75 / 10 10 10 10 10 LUBBOCK 84 60 87 56 75 / 20 20 10 10 10 DENVER CITY 85 60 87 57 77 / 10 10 10 10 10 BROWNFIELD 85 59 88 57 77 / 20 10 10 10 10 CHILDRESS 88 64 93 58 78 / 20 30 20 20 10 SPUR 86 62 91 64 81 / 20 30 10 20 10 ASPERMONT 89 67 93 69 85 / 20 20 20 20 20 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 99/99/05
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
630 AM CDT TUE SEP 30 2014 .DISCUSSION...UPDATED FOR LATEST AVIATION DISCUSSION BELOW. && .AVIATION...PATCHY DENSE FOG IS CURRENTLY IMPACTING THE KBRO TERMINAL AND CEILINGS HAVE LOWER BETWEEN IFR TO LIFR CONDITIONS ACROSS MFE AND HRL. THESE VISIBILITIES WILL BEGIN TO IMPROVE WITH DAYTIME HEATING BY MID MORNING. THE WEAK LOW IS CURRENTLY MOVING SLOWLY NORTH INTO CRP AREA. THIS WILL LIMIT THE POTENTIAL FOR RAIN ACROSS THE LOWER TEXAS GULF WATERS. HOWEVER...LINGERING MOISTURE ACROSS THE AREA WILL ENHANCE A FEW ISOLATED SHOWERS EARLY IN THE AFTERNOON. THE WINDS WILL BE LIGHT AND VARIABLE THROUGH MUCH OF THE MORNING HOURS AND VEER SOUTHEAST THIS AFTERNOON WITH VFR CONDITIONS RETURNING. && .PREV DISCUSSION... /ISSUED 332 AM CDT TUE SEP 30 2014/ SHORT TERM /NOW THROUGH THROUGH WEDNESDAY/...LATEST SATELLITE AND WATER VAPOR OBSERVATIONS SHOW RIDGE MIGRATING EASTWARD AS A STRONG LOW PRESSURE MOVES ACROSS THE ROCKIES INTO THE UPPER MIDWEST TODAY. THIS TROUGH WILL PUSH THE HIGH PRESSURE EAST AND DEEPENS THE LEE SIDE TROUGH ACROSS WESTERN TEXAS EXTENDING INTO THE CWA GRADUALLY INCREASING WINDS BY THE END OF THE SHORT TERM PERIOD. IR SATELLITE IMAGERY SHOWS THE WEAK SURFACE LOW PRESSURE CENTER OVER SOUTHERN HIDALGO COUNTY AND UNDERNEATH DEEP LOW LEVEL MOISTURE IS DEPICTED OVER THE AREA WITH 00Z KBRO SOUNDING SHOWING DEEP MOISTURE CONCENTRATED UP TO 800 MB. PRECIPITABLE WATERS ONLY REACH 1.72 INCHES AND THAT IS DUE TO THE DRY MID LEVEL AIR MOVING IN WITH THE NORTHWEST FLOW ALOFT. AS OF 8Z...RADAR SHOWS SOME ISOLATED SHOWER DEVELOPMENT FAVORING NORTHERN KENEDY COUNTY AND EASTERN HIDALGO AND CAMERON AND IT IS MAINLY RAP RAP AROUND THE WEAK LOW/MCV. THE CONVECTION PATTERN WILL CONTINUE THROUGH THE EARLY MORNING HOURS AND MOVE INTO BROOKS COUNTY BY MID DAY AS THE WEAK LOW MOVES FURTHER INLAND BEFORE IT GETS TAKEN BY THE MID TO UPPER FLOW ASSOCIATED WITH THE RIDGE. THIS WILL MAINTAIN SHOWERS ALONG THE COAST AND THE GULF WATERS LATE TODAY INTO WED. LEFT INHERITED 10 PERCENT AS AN ISOLATED SHOWER CAN NOT BE RULED OUT. THE WINDS WILL BE LIGHT AND VARIABLE FOR THE MOST PART TODAY WITH PATCHY FOG AND LOW CIGS THROUGH THE EARLY MORNING HOURS. TEMPERATURES WILL REACH THE MID TO UPPER 80S AND CLOSE TO 90S ALONG THE RIVER OVER THE WESTERN COUNTIES. TONIGHT THE DRY AIR WILL LOWER THE CHANCE OF MORE SHOWERS ACROSS THE AREA SO LEAN TOWARDS 10 POPS THROUGH THE NIGHT. AS THE TROUGH OVER THE PACIFIC NORTHWEST DIGS SOUTH WEDNESDAY...THE PRESSURE GRADIENT STRENGTHENS A BIT RETURNING SOUTHEAST FLOW ACROSS THE CWA ALLOWING FOR THAT WEAK LOW TO DISSIPATE. SE WINDS WILL INCREASE ESPECIALLY ALONG THE COAST WITH MORE ABUNDANT SUNSHINE EXPECTED. LOW CHANCE OF RAIN AND LOW AMOUNT OF CLOUD COVER WILL ALLOW FOR HIGH TEMPS TO RETURN TO THE 90S ACROSS MOST LOCATIONS IN THE CWA WITH THE EXCEPTION ALONG THE COAST. LOW CHANCES OF RAIN WILL REMAIN OVER THE GULF WATERS AS DRY AIR GRADUALLY DIMINISHES ANY ADDITIONAL DEVELOPMENT OVER THE AREA. TODAY DUE TO THE LIGHT TO VARIABLE WINDS AND ABUNDANT MOISTURE IN PLACE LINGERING AROUND THE AREA WILL ALLOW FOR FAVORABLE CONDITIONS FOR PATCHY GROUND FOG TO DEVELOP. VISIBILITIES WILL IMPROVE WITH DAY TIME HEATING IN THE MORNING HOUR. LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...500MB TROUGH ACROSS THE WESTERN UNITED STATES WEDNESDAY WILL MOVE EASTWARD ACROSS THE CENTRAL U.S. THURSDAY BRINGING A WEAK COLD FRONT INTO CENTRAL TEXAS THURS AFTERNOON. LOW TO MID LEVEL MOISTURE WILL POOL ALONG AND AHEAD OF THE FRONT THURS NIGHT INTO FRIDAY AS THE FRONT MOVES INTO THE RIO GRANDE VALLEY FRI AFTERNOON. THIS WILL PROVIDE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE AREA LATE THURSDAY INTO FRIDAY. RAIN CHANCES WILL LINGER ACROSS THE RGV FRI NIGHT THROUGH SAT NIGHT AS THE FRONT MOVES INTO NORTHEAST MEXICO AND STALLS AND MOISTURE CONTINUES TO POOL ACROSS NORTHERN TAMAULIAPAS. DRIER AND SLIGHTLY COOLER AIR IS EXPECTED TO FILTER INTO SOUTH TX THROUGH THE WEEKEND BEFORE THE SURFACE RIDGE ACROSS EAST TX SATURDAY MOVES EASTWARD INTO EARLY NEXT WEEK. MARINE... NOW THROUGH WEDNESDAY...THE WINDS AND SEAS WILL REMAIN LIGHT TO MODERATE AS THE WEAK LOW KEEPS SPINNING OVER THE AREA PRODUCING ERRATIC WINDS BETWEEN 10 T 15 KNOTS. THIS LOW IS HELPING PRODUCE ISOLATED SHOWERS AT THIS TIME AND DO EXPECT THE SAME PATTERN TO CONTINUE TODAY AND IMPROVE WEDNESDAY. THE SEAS WILL REMAIN LOW THROUGH THE PERIOD WITH NO SCA BUT A SCEC IS POSSIBLE WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WED NIGHT INTO THURSDAY BEFORE A WEAK COLD FRONT MOVES THROUGH THE LOWER TEXAS COAST FRIDAY. WINDS WILL SHIFT TO THE NORTH AND NORTHEAST FRI AFTERNOON AS A RESULT. THE PRESSURE GRADIENT WILL WEAKEN ACROSS THE WESTERN GULF OF MEXICO SATURDAY ALLOWING WINDS TO BECOME LIGHT FROM THE NORTHEAST. && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 67/60
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
437 AM CDT TUE SEP 30 2014 .SHORT TERM... /Today and Tonight/ A compact upper low embedded within a broader western CONUS trough, will lift northeast across the Dakotas today. Westerly flow aloft within the base of the upper trough will induce a weak surface trough in the lee of the Rockies today, with the trough axis extending south across West Texas. Isolated to scattered convection is expected to develop along and east of this feature late this afternoon and evening. Some of this activity may reach far western sections by early evening, with the most favored area across the western Big Country counties generally west of a Throckmorton to Sweetwater line. Kept 20 POPs going across this area this evening and overnight. Convection should be more isolated farther south, but could move into far western portions of the Concho Valley and Crockett county by early evening. It is interesting to note that the RUC and some of the high resolution models develop convection farther east across the Big Country and Concho valley during peak heating. While this can`t be ruled out entirely, due to minimal CAP and a convective temperature around 90 degrees, the lack of any surface feature will preclude mentioning POPs at this time. The thermal ridge will be a bit stronger and farther east today, which will result in afternoon highs in the upper 80s to around 90 degrees. Lows tonight will be mainly in the upper 60s. .LONG TERM... /Wednesday through Monday/ The main concern in the extended forecast is the potential for showers and thunderstorms in association with a cold front, followed by cooler temperatures. Highs on Wednesday will be above seasonal normals, generally in the lower to mid 90s. The NAM is indicating some convergence along a surface trough, mainly across the western Big Country, during the late afternoon/evening hours Wednesday, resulting in isolated showers and thunderstorms. Slight chance PoPs were included across the western Big Country for this time frame. An upper level trough will move across The Rockies Wednesday, then across the Plains Thursday. This will send a cold front through West Central Texas during the day Thursday, clearing the area by early evening. Isolated to scattered showers and thunderstorms will be possible along the front, mainly across the southern and eastern half of the area, where better moisture will reside. Only minor tweaks were made to the current PoPs, with the best chance across the Northwest Hill Country. Cooler, near seasonal, temperatures are forecast behind the front on Friday and Saturday, with highs in the low to mid 80s, and overnight lows in the 50s to near 60. A slow warm up will ensue Sunday through early next week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 89 69 91 71 87 / 10 10 10 20 20 San Angelo 91 69 92 72 88 / 5 10 5 10 20 Junction 88 67 91 73 90 / 0 5 5 10 20 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 24/Daniels
AREA FORECAST DISCUSSION
NWS LUBBOCK TX
356 AM CDT TUE SEP 30 2014 .SHORT TERM... A MOISTURE PLUME WAS PULLING UP INTO THE TEXAS SOUTH PLAINS REGION THIS MORNING FROM THE TROPICAL NORTHEAST PACIFIC OCEAN...WHILE AN UPPER LOW WAS SPINNING OFF INTO THE NORTHERN PLAINS. A TRAILING IMPULSE EJECTING THROUGH EAST-CENTRAL COLORADO MAY BE IN TANDEM WITH A WEAKER IMPULSE CROSSING THE MOIST PLUME OVER WEST TEXAS. ISOLATED EARLY MORNING SHOWERS WERE CROSSING THE SOUTH PLAINS...HEADING INTO THE ROLLING PLAINS LATER THIS MORNING. ALTHOUGH SIGNIFICANT LIFT IS DIFFICULT TO IDENTIFY IN THIS PATTERN...WE EXPECT TO REMAIN WITHIN THE MOIST PLUME THROUGH THIS EVENING AND SUBJECT TO AT LEAST WEAK FORCING FROM THE TRAILING SOUTHERN PORTION OF THE SYSTEM. MAJORITY OF SOLUTIONS CONTINUE TO BREAK THUNDERSTORMS OUT NEAR OR JUST EAST OF THE CENTRAL SOUTH PLAINS LATE THIS AFTERNOON AND EARLY THIS EVENING AS SURFACE CONVERGENCE TIGHTENS A DRYLINE WITH POTENTIAL SURFACE DEWPOINTS STILL IN THE LOWER OR EVEN MIDDLE 60S LYING JUST TO THE EAST. STILL SOME CONCERN OVER POSSIBLE ERRORS IN MODEL DEPICTION OF SURFACE DEWPOINT STRUCTURE...BUT OVERNIGHT TRENDS IN WRF/NAM AND RAP SEEM TO GIVE SOME CREDENCE TO THE HIGHER MOISTURE LEVELS. AND THIS WOULD GENERATE CONVECTIVE ENERGY UP TO 2500 JOULES PER KILOGRAM WITH MODEST SHEAR OF 25-30 KNOTS SUGGESTING POTENTIAL FOR A FEW HEFTY STORMS IN THIS AREA LATER TODAY. WE HAVE EDGED PREVIOUS THUNDER CHANCES SLIGHTLY BACK TO THE SOUTH AND WEST FOR LATER TODAY WHILE RETAINING BULK OF PREVIOUS FORECAST. WARM TEMPERATURES ARE EXPECTED THIS AFTERNOON....FAVORED A CONSALL/ CONSRAW ENSEMBLE APPROACH A NOTCH WARMER THAN PREVIOUS FORECAST. RMCQUEEN && .LONG TERM... PRECIPITATION CHANCES WILL CONTINUE ON WEDNESDAY INTO THURSDAY MORNING BEFORE AN EXTENDED DRY PERIOD DOMINATES THE WEATHER PATTERN. A COLD FRONT/RETREATING DRYLINE MAY BE THE FOCUS FOR THUNDERSTORM DEVELOPMENT ON WEDNESDAY EVENING AS ANOTHER SHORTWAVE TROUGH MOVES ACROSS THE ROCKIES. HOWEVER...THIS TROUGH IS POSITIVELY TILTED AS IT BARRELS OUT ONTO THE PLAINS BY THURSDAY. FURTHERMORE...THE TIMING OF THE TROUGH AXIS IS NOT GREAT. A BULK OF THE LARGE SCALE LIFT WILL NOT SPREAD OVER THE AREA UNTIL THURSDAY MORNING. WE WILL STILL SEE A GOOD AREA OF HEIGHT FALLS UNTIL THIS POINT. LOW LEVEL MOISTURE WILL HANG ON TO AT LEAST THE SOUTHERN ROLLING PLAINS EAST OF THE DRYLINE. BUT MID AND UPPER LEVELS WILL BE SIGNIFICANTLY DRIER THAN TODAY. THE COLD FRONT FROM THIS SHORTWAVE TROUGH WILL PUNCH THROUGH ON THURSDAY MORNING INTO THE EARLY AFTERNOON. IT WILL NOT PLOW THROUGH THE SOUTHERN ROLLING PLAINS UNTIL LATE MORNING OR EARLY AFTERNOON LEAVING POSSIBLE STORM CHANCES IN THIS AREA. AFTER THE COLD FRONT AND TROUGH ON THURSDAY...DRY NORTHWEST FLOW WILL ENTER THE REGION WITH RIDGING OVER THE WESTERN US. A WEAK SHORT WAVE ON SUNDAY WILL HAVE LITTLE CONSEQUENCE ON ANY WEATHER IMPACTS. TEMPERATURES WILL BE QUITE COOL IN THE MORNING WITH FRIDAY AND SATURDAY MORNINGS THE COOLEST DIPPING DOWN INTO THE 40S. && .PRELIMINARY POINT TEMPS/POPS... FRIONA 80 54 83 52 71 / 10 0 0 0 0 TULIA 83 57 86 55 73 / 10 20 10 10 10 PLAINVIEW 83 58 86 55 73 / 20 20 10 10 10 LEVELLAND 84 59 86 56 75 / 10 10 10 10 10 LUBBOCK 84 60 87 56 75 / 20 20 10 10 10 DENVER CITY 85 60 87 57 77 / 10 10 10 10 10 BROWNFIELD 85 59 88 57 77 / 20 10 10 10 10 CHILDRESS 88 64 93 58 78 / 20 30 20 20 10 SPUR 86 62 91 64 81 / 20 30 10 20 10 ASPERMONT 89 67 93 69 85 / 20 20 20 20 20 && .LUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/01
AREA FORECAST DISCUSSION...CORRECTED
NWS BROWNSVILLE TX
332 AM CDT TUE SEP 30 2014 .SHORT TERM /NOW THROUGH THROUGH WEDNESDAY/...LATEST SATELLITE AND WATER VAPOR OBSERVATIONS SHOW RIDGE MIGRATING EASTWARD AS A STRONG LOW PRESSURE MOVES ACROSS THE ROCKIES INTO THE UPPER MIDWEST TODAY. THIS TROUGH WILL PUSH THE HIGH PRESSURE EAST AND DEEPENS THE LEE SIDE TROUGH ACROSS WESTERN TEXAS EXTENDING INTO THE CWA GRADUALLY INCREASING WINDS BY THE END OF THE SHORT TERM PERIOD. IR SATELLITE IMAGERY SHOWS THE WEAK SURFACE LOW PRESSURE CENTER OVER SOUTHERN HIDALGO COUNTY AND UNDERNEATH DEEP LOW LEVEL MOISTURE IS DEPICTED OVER THE AREA WITH 00Z KBRO SOUNDING SHOWING DEEP MOISTURE CONCENTRATED UP TO 800 MB. PRECIPITABLE WATERS ONLY REACH 1.72 INCHES AND THAT IS DUE TO THE DRY MID LEVEL AIR MOVING IN WITH THE NORTHWEST FLOW ALOFT. AS OF 8Z...RADAR SHOWS SOME ISOLATED SHOWER DEVELOPMENT FAVORING NORTHERN KENEDY COUNTY AND EASTERN HIDALGO AND CAMERON AND IT IS MAINLY RAP RAP AROUND THE WEAK LOW/MCV. THE CONVECTION PATTERN WILL CONTINUE THROUGH THE EARLY MORNING HOURS AND MOVE INTO BROOKS COUNTY BY MID DAY AS THE WEAK LOW MOVES FURTHER INLAND BEFORE IT GETS TAKEN BY THE MID TO UPPER FLOW ASSOCIATED WITH THE RIDGE. THIS WILL MAINTAIN SHOWERS ALONG THE COAST AND THE GULF WATERS LATE TODAY INTO WED. LEFT INHERITED 10 PERCENT AS AN ISOLATED SHOWER CAN NOT BE RULED OUT. THE WINDS WILL BE LIGHT AND VARIABLE FOR THE MOST PART TODAY WITH PATCHY FOG AND LOW CIGS THROUGH THE EARLY MORNING HOURS. TEMPERATURES WILL REACH THE MID TO UPPER 80S AND CLOSE TO 90S ALONG THE RIVER OVER THE WESTERN COUNTIES. TONIGHT THE DRY AIR WILL LOWER THE CHANCE OF MORE SHOWERS ACROSS THE AREA SO LEAN TOWARDS 10 POPS THROUGH THE NIGHT. AS THE TROUGH OVER THE PACIFIC NORTHWEST DIGS SOUTH WEDNESDAY...THE PRESSURE GRADIENT STRENGTHENS A BIT RETURNING SOUTHEAST FLOW ACROSS THE CWA ALLOWING FOR THAT WEAK LOW TO DISSIPATE. SE WINDS WILL INCREASE ESPECIALLY ALONG THE COAST WITH MORE ABUNDANT SUNSHINE EXPECTED. LOW CHANCE OF RAIN AND LOW AMOUNT OF CLOUD COVER WILL ALLOW FOR HIGH TEMPS TO RETURN TO THE 90S ACROSS MOST LOCATIONS IN THE CWA WITH THE EXCEPTION ALONG THE COAST. LOW CHANCES OF RAIN WILL REMAIN OVER THE GULF WATERS AS DRY AIR GRADUALLY DIMINISHES ANY ADDITIONAL DEVELOPMENT OVER THE AREA. TODAY DUE TO THE LIGHT TO VARIABLE WINDS AND ABUNDANT MOISTURE IN PLACE LINGERING AROUND THE AREA WILL ALLOW FOR FAVORABLE CONDITIONS FOR PATCHY GROUND FOG TO DEVELOP. VISIBILITIES WILL IMPROVE WITH DAY TIME HEATING IN THE MORNING HOUR. .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...500MB TROUGH ACROSS THE WESTERN UNITED STATES WEDNESDAY WILL MOVE EASTWARD ACROSS THE CENTRAL U.S. THURSDAY BRINGING A WEAK COLD FRONT INTO CENTRAL TEXAS THURS AFTERNOON. LOW TO MID LEVEL MOISTURE WILL POOL ALONG AND AHEAD OF THE FRONT THURS NIGHT INTO FRIDAY AS THE FRONT MOVES INTO THE RIO GRANDE VALLEY FRI AFTERNOON. THIS WILL PROVIDE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE AREA LATE THURSDAY INTO FRIDAY. RAIN CHANCES WILL LINGER ACROSS THE RGV FRI NIGHT THROUGH SAT NIGHT AS THE FRONT MOVES INTO NORTHEAST MEXICO AND STALLS AND MOISTURE CONTINUES TO POOL ACROSS NORTHERN TAMAULIAPAS. DRIER AND SLIGHTLY COOLER AIR IS EXPECTED TO FILTER INTO SOUTH TX THROUGH THE WEEKEND BEFORE THE SURFACE RIDGE ACROSS EAST TX SATURDAY MOVES EASTWARD INTO EARLY NEXT WEEK. && .MARINE... NOW THROUGH WEDNESDAY...THE WINDS AND SEAS WILL REMAIN LIGHT TO MODERATE AS THE WEAK LOW KEEPS SPINNING OVER THE AREA PRODUCING ERRATIC WINDS BETWEEN 10 T 15 KNOTS. THIS LOW IS HELPING PRODUCE ISOLATED SHOWERS AT THIS TIME AND DO EXPECT THE SAME PATTERN TO CONTINUE TODAY AND IMPROVE WEDNESDAY. THE SEAS WILL REMAIN LOW THROUGH THE PERIOD WITH NO SCA BUT A SCEC IS POSSIBLE WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WED NIGHT INTO THURSDAY BEFORE A WEAK COLD FRONT MOVES THROUGH THE LOWER TEXAS COAST FRIDAY. WINDS WILL SHIFT TO THE NORTH AND NORTHEAST FRI AFTERNOON AS A RESULT. THE PRESSURE GRADIENT WILL WEAKEN ACROSS THE WESTERN GULF OF MEXICO SATURDAY ALLOWING WINDS TO BECOME LIGHT FROM THE NORTHEAST. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 85 77 87 80 / 20 10 10 10 BROWNSVILLE 87 76 89 79 / 20 10 10 10 HARLINGEN 88 75 90 79 / 20 10 10 10 MCALLEN 89 76 92 79 / 20 10 10 10 RIO GRANDE CITY 90 75 93 78 / 20 10 10 10 SOUTH PADRE ISLAND 83 79 85 81 / 20 10 10 20 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 67/61
AREA FORECAST DISCUSSION
NWS BROWNSVILLE TX
330 AM CDT TUE SEP 30 2014 .SHORT TERM /NOW THROUGH THROUGH WEDNESDAY/...LATEST SATELLITE AND WATER VAPOR OBSERVATIONS SHOW RIDGE MIGRATING EASTWARD AS A STRONG LOW PRESSURE MOVES ACROSS THE ROCKIES INTO THE UPPER MIDWEST TODAY. THIS TROUGH WILL PUSH THE HIGH PRESSURE EAST AND DEEPENS THE LEE SIDE TROUGH ACROSS WESTERN TEXAS EXTENDING INTO THE CWA GRADUALLY INCREASING WINDS BY THE END OF THE SHORT TERM PERIOD. IR SATELLITE IMAGERY SHOWS THE WEAK SURFACE LOW PRESSURE CENTER OVER SOUTHERN HIDALGO COUNTY AND UNDERNEATH DEEP LOW LEVEL MOISTURE IS DEPICTED OVER THE AREA WITH 00Z KBRO SOUNDING SHOWING DEEP MOISTURE CONCENTRATED UP TO 800 MB. PRECIPITABLE WATERS ONLY REACH 1.72 INCHES AND THAT IS DUE TO THE DRY MID LEVEL AIR MOVING IN WITH THE NORTHWEST FLOW ALOFT. AS OF 8Z...RADAR SHOWS SOME ISOLATED SHOWER DEVELOPMENT FAVORING NORTHERN KENEDY COUNTY AND EASTERN HIDALGO AND CAMERON AND IT IS MAINLY RAP RAP AROUND THE WEAK LOW/MCV. THE CONVECTION PATTERN WILL CONTINUE THROUGH THE EARLY MORNING HOURS AND MOVE INTO BROOKS COUNTY BY MID DAY AS THE WEAK LOW MOVES FURTHER INLAND BEFORE IT GETS TAKEN BY THE MID TO UPPER FLOW ASSOCIATED WITH THE RIDGE. THIS WILL MAINTAIN SHOWERS ALONG THE COAST AND THE GULF WATERS LATE TODAY INTO WED. LEFT INHERITED 10 PERCENT AS AN ISOLATED SHOWER CAN NOT BE RULED OUT. THE WINDS WILL BE LIGHT AND VARIABLE FOR THE MOST PART TODAY WITH PATCHY FOG AND LOW CIGS THROUGH THE EARLY MORNING HOURS. TEMPERATURES WILL REACH THE MID TO UPPER 80S AND CLOSE TO 90S ALONG THE RIVER OVER THE WESTERN COUNTIES. TONIGHT THE DRY AIR WILL LOWER THE CHANCE OF MORE SHOWERS ACROSS THE AREA SO LEAN TOWARDS 10 POPS THROUGH THE NIGHT. AS THE TROUGH OVER THE PACIFIC NORTHWEST DIGS SOUTH WEDNESDAY...THE PRESSURE GRADIENT STRENGTHENS A BIT RETURNING SOUTHEAST FLOW ACROSS THE CWA WEDNESDAY. WINDS WILL INCREASE ESPECIALLY ALONG THE COAST WITH MORE ABUNDANT SUNSHINE EXPECTED. LOW CHANCE OF RAIN AND LOW AMOUNT OF CLOUD COVER WILL ALLOW FOR HIGH TEMPS TO RETURN TO THE 90S ACROSS MOST LOCATIONS IN THE CWA WITH THE EXCEPTION ALONG THE COAST. CHANCES OF RAIN WILL REMAIN OVER THE GULF WATERS AS DRY AIR COMPLETELY DIMINISHES THE POTENTIAL AND THE WEAK LOW IS NO LONGER IN PLACE TO PROVIDE A MORE FAVORABLE ENVIRONMENT FOR DEVELOPMENT ONCE AGAIN. TODAY DUE TO THE LOW TO VARIABLE WIND AND ABUNDANT MOISTURE FROM PREVIOUS RAIN LINGERING AROUND THE AREA WILL ALLOW FOR FAVORABLE CONDITIONS FOR PATCHY GROUND FOG. .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...500MB TROUGH ACROSS THE WESTERN UNITED STATES WEDNESDAY WILL MOVE EASTWARD ACROSS THE CENTRAL U.S. THURSDAY BRINGING A WEAK COLD FRONT INTO CENTRAL TEXAS THURS AFTERNOON. LOW TO MID LEVEL MOISTURE WILL POOL ALONG AND AHEAD OF THE FRONT THURS NIGHT INTO FRIDAY AS THE FRONT MOVES INTO THE RIO GRANDE VALLEY FRI AFTERNOON. THIS WILL PROVIDE A CHANCE OF SHOWERS AND THUNDERSTORMS ACROSS THE AREA LATE THURSDAY INTO FRIDAY. RAIN CHANCES WILL LINGER ACROSS THE RGV FRI NIGHT THROUGH SAT NIGHT AS THE FRONT MOVES INTO NORTHEAST MEXICO AND STALLS AND MOISTURE CONTINUES TO POOL ACROSS NORTHERN TAMAULIAPAS. DRIER AND SLIGHTLY COOLER AIR IS EXPECTED TO FILTER INTO SOUTH TX THROUGH THE WEEKEND BEFORE THE SURFACE RIDGE ACROSS EAST TX SATURDAY MOVES EASTWARD INTO EARLY NEXT WEEK. && .MARINE... NOW THROUGH WEDNESDAY...THE WINDS AND SEAS WILL REMAIN LIGHT TO MODERATE AS THE WEAK LOW KEEPS SPINNING OVER THE AREA PRODUCING ERRATIC WINDS BETWEEN 10 T 15 KNOTS. THIS LOW IS HELPING PRODUCE ISOLATED SHOWERS AT THIS TIME AND DO EXPECT THE SAME PATTERN TO CONTINUE TODAY AND IMPROVE WEDNESDAY. THE SEAS WILL REMAIN LOW THROUGH THE PERIOD WITH NO SCA BUT A SCEC IS POSSIBLE WEDNESDAY. WEDNESDAY NIGHT THROUGH SATURDAY...LIGHT TO MODERATE SOUTHEAST WINDS WILL PREVAIL ACROSS THE COASTAL WATERS WED NIGHT INTO THURSDAY BEFORE A WEAK COLD FRONT MOVES THROUGH THE LOWER TEXAS COAST FRIDAY. WINDS WILL SHIFT TO THE NORTH AND NORTHEAST FRI AFTERNOON AS A RESULT. THE PRESSURE GRADIENT WILL WEAKEN ACROSS THE WESTERN GULF OF MEXICO SATURDAY ALLOWING WINDS TO BECOME LIGHT FROM THE NORTHEAST. && .PRELIMINARY POINT TEMPS/POPS... BAYVIEW/PORT ISABEL 85 77 87 80 / 20 10 10 10 BROWNSVILLE 87 76 89 79 / 20 10 10 10 HARLINGEN 88 75 90 79 / 20 10 10 10 MCALLEN 89 76 92 79 / 20 10 10 10 RIO GRANDE CITY 90 75 93 78 / 20 10 10 10 SOUTH PADRE ISLAND 83 79 85 81 / 20 10 10 20 && .BRO WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$ THIS PRODUCT IS ALSO AVAILABLE ON THE WEB AT: HTTP://WEATHER.GOV/RGV 67/61
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1050 PM CDT WED OCT 1 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .SHORT TERM...TONIGHT AND THURSDAY ISSUED AT 328 PM CDT WED OCT 1 2014 PRECIPITATION TIMING IS THE MAIN CONCERN DURING THIS PART OF THE FORECAST. RADAR TIME LAPSE INDICATED SHOWERS MOVING INTO CENTRAL WISCONSIN THIS AFTERNOON AHEAD OF A MID LEVEL SHORT WAVE. THESE SHOWERS WERE DECREASING IN COVERAGE AND INTENSITY AS THEY CONTINUED INTO NORTH CENTRAL WISCONSIN. HRRR MODEL APPEARED TO DO A BETTER JOB OF DEPICTING THIS THAN THE NAM/GFS/EC/SREF. STILL...HAVE LEFT SHOWERS WITH A SLIGHT CHANCE OF THUNDER DUE TO THE APPROACHING COLD FRONT AND SOME ELEVATED INSTABILITY THAT IS FORECAST FOR TONIGHT. SURFACE FLOW BECOMES QUITE LIGHT TOWARD DAYBREAK...DUE TO A WEAK SURFACE PRESSURE GRADIENT. HAVE AREAS OF FOG AROUND DAYBREAK DUE TO THE COMBINATION OF MOISTURE...LIGHT OR CALM WINDS...AND 12Z MOS GUIDANCE SHOWING LOW VISIBILITIES IN FOG. THE BETTER CHANCE FOR SHOWERS AND THUNDERSTORMS ON THURSDAY SHOULD BE IN THE AFTERNOON AS A LOW PRESSURE SYSTEM MOVES ALONG THE FRONT TOWARD WISCONSIN. HAVE RAIN AND THUNDER CHANCES INCREASING DURING THE AFTERNOON AS THE LOW APPROACHES. THE WET CONDITIONS SHOULD KEEP LOW TEMPERATURES ABOVE NORMAL...AND WARM ADVECTION AHEAD OF THE LOW PRESSURE SYSTEM WILL LEAD TO WARMER THAN NORMAL CONDITIONS ON THURSDAY. .LONG TERM...THURSDAY NIGHT THROUGH WEDNESDAY ISSUED AT 328 PM CDT WED OCT 1 2014 PCPN TRENDS AND TEMPERATURES WILL BE THE MAIN FCST CONCERNS. MODELS HAVE COME INTO GOOD AGREEMENT ON A SFC LOW LIFTING NNE ALONG A STRONG COLD FRONT THURSDAY NIGHT...AND SPREADING WIDESPREAD SHOWERS ACROSS THE FORECAST AREA. WILL CARRY CATEGORICAL POPS FOR THURSDAY EVENING. A FEW TSTMS SHOULD BE EMBEDDED WITHIN THE SHOWER ACTIVITY EAST OF THE FRONTAL BOUNDARY...OVER ROUGHLY THE SE HALF OF THE FCST AREA. A DECREASE IN THE SHOWER ACTIVITY IS EXPECTED OVER CENTRAL AND NORTH CENTRAL WI OVERNIGHT...AND THE REST OF THE AREA ON FRIDAY MORNING...BUT SCT SHOWERS WILL CONTINUE INTO FRIDAY AFTERNOON AS A DEEP UPPER TROF/UPPER LOW APPROACHES. IN THE WAKE OF THE COLD FRONT...FRIDAY`S HIGH TEMPERATURES SHOULD BE 10-15 DEGREES COOLER THAN ON THURSDAY. THE UPPER TROF WILL SHIFT EAST ACROSS THE REGION ON FRIDAY NIGHT... SO SCT SHOWERS WILL CONTINUE. SHOWERS WILL LIKELY BECOME LAKE- ENHANCED OVER NC WI...WHERE COLD NW FLOW WILL MOVE ACROSS LAKE SUPERIOR. WILL KEEP LIKELY POPS THERE. WILL CONTINUE THE MENTION OF MIXED RAIN/SNOW SHOWERS OVER FAR NC WI LATE...AS H8 TEMPS DROP TO -2 TO -4 C. A LIGHT MIX OF RAIN/SNOW SHOWERS SHOULD CONTINUE INTO SATURDAY MORNING OVER NORTHERN WI...THEN TAPER OFF DURING THE AFTERNOON AS WIND TRAJECTORIES BECOME WEST-NORTHWEST. SATURDAY NIGHT THROUGH MONDAY NIGHT...THE WEATHER PATTERN WILL BE DOMINATED BY AN UPPER LOW OVER ONTARIO..WITH SEVERAL S/W TROFS ROTATING THROUGH WI. MOISTURE WILL BE LIMITED AND LLVL WINDS WILL BE TOO WESTERLY FOR ANY SIGNIFICANT LAKE-EFFECT. WILL HAVE LOW POPS (15-30 PERCENT) OVER MOST OF THE REGION DURING THIS PERIOD... ALONG WITH CHILLY TEMPERATURES. IF PCPN OCCURS OVER NORTHERN WI... A LIGHT MIX OF RAIN/SNOW WILL BE POSSIBLE DURING THE LATE NIGHT/MORNING PERIODS. EXPECT DRIER CONDITIONS TO PREVAIL INTO MIDWEEK...WITH A BIT OF A WARMUP POSSIBLE. THIS IS A LOW CONFIDENCE FORECAST THOUGH... AS MODELS SHOW A WIDE RANGE OF H8 TEMPS OVER THE WSTRN GREAT LAKES. HAVE DISCOUNTED THE H8 TEMPS OF +16 TO +20 OFF THE 00Z ECMWF...AS THEY SEEM ANOMALOUS COMPARED TO THE ENSEMBLE MEANS...AND UNLIKELY WITH A FAIRLY ZONAL FLOW PATTERN. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1050 PM CDT WED OCT 1 2014 SCATTERED SHOWERS WILL MOVE FROM WEST TO EAST ACROSS THE REGION TONIGHT. CEILINGS AND VISIBILITIES WILL GRADUALLY LOWER TO IFR IN MOST PLACES LATE TONIGHT. ADDITIONAL SHOWERS AND A FEW THUNDERSTORMS ARE LIKELY THURSDAY...ESPECIALLY IN THE AFTERNOON AND EVENING. IFR CEILINGS AND VISIBILITIES SHOULD RISE FROM IFR EARLY TO MVFR IN THE AFTERNOON BEFORE DROPPING DURING THE EVENING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MG LONG TERM......KIECKBUSCH AVIATION.......RDM
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
852 PM CDT WED OCT 1 2014 .UPDATE... AS MENTIONED IN THE PREVIOUS DISCUSSION...WEAK WARM ADVECTION COMBINED WITH A WEAK SHORT WAVE PUSHING IN IS HELPING TO TRIGGER SOME SHOWERS ACROSS THE WESTERN FORECAST AREA THIS EVENING. THE LOW LEVEL JET IS ALSO DRIFTING INTO THE AREA AND HELPING THINGS ALONG. OVERALL THE FORCING IS WEAK...SO EXPECT MAINLY SCT SHOWERS WITH A THUNDERSTORM POSSIBLE. THE HRRR IS SHOWING THE SCATTERED STUFF IN THE WEST FAIRLY ACCURATELY. HOWEVER...IT SEEMS TO BE TOO FAR NORTH AND TOO STRONG WITH THE PRECIP MOVING ACROSS ILLINOIS. THE HRRR BRINGS THIS IN ACROSS OUR SOUTHEAST RATHER SOLIDLY AND THIS LOOKS OVERDONE. GIVEN TRENDS...I MAY HAVE TO BACK AWAY FROM THE LIKELY POPS AND KEEP IT MORE IN THE HIGH CHC CATEGORY IF THINGS DON/T START TO EXPAND OVER THE NEXT HOUR OR SO. IT LOOKS LIKE ALL OF THIS WILL MOVE OUT BY ABOUT 4 AM TONIGHT WITH A LULL IN THE PRECIP UNTIL THE NEXT ROUND MOVES IN DURING THE AFTERNOON ON THURSDAY. TEMPS WON/T DROP MUCH FROM HERE WITH THE WARM ADVECTION ONGOING. && .AVIATION/06Z TAFS/... THERE IS A CHANCE OF SHOWERS OR AN ISOLATED THUNDERSTORM OVERNIGHT. TRENDS ARE LOOKING A BIT DRIER THAN THE MODELS INDICATED EARLIER. THESE SHOWERS SHOULD MOVE OUT BY AROUND 09Z THURSDAY WITH A LULL IN THE PRECIPITATION EXPECTED UNTIL MORE ARRIVES THURSDAY AFTERNOON. WINDS FALL OFF LATER TONIGHT WITHIN A WEAK TROF MOVING IN. MUCH OF THE MODEL GUIDANCE IS INDICATING MVFR CIGS/VSBYS DEVELOPING BTWN 09-10Z THU AND CONTINUING THROUGH ABOUT 15-17Z THU. WE MAY EVEN SEE SOME IFR CIGS DEVELOP FOR A SHORT TIME...CENTERED AROUND SUNRISE. VFR CONDITIONS SHOULD RETURN AHEAD OF THE NEXT ROUND OF RAIN BY EARLY THURSDAY EVENING. IN THE OUTLOOK FOR THURSDAY EVENING...MORE MVFR CIGS/VSBYS ARE ANTICIPATED AS LOW PRESSURE MOVES OVERHEAD. && .PREV DISCUSSION... /ISSUED 341 PM CDT WED OCT 1 2014/ SHORT TERM... TONIGHT AND THURSDAY...FORECAST CONFIDENCE HIGH. WARM ADVECTION ALOFT COMBINED WITH A PASSING SHORTWAVE WILL KICK OFF SHOWERS AND A FEW STORMS THIS EVENING INTO TONIGHT. BEST CHANCE BASED ON LATEST MESOSCALE MODELS SEEMS TO BE FROM AROUND MIDNIGHT UNTIL AROUND DAYBREAK. KEPT TEMPS ON THE MILDER SIDE TONIGHT DUE TO CLOUDS AND WARM ADVECTION. LOOKS LIKE A LULL IN PRECIP TOMORROW MORNING...WITH MORE SHOWERS AND STORMS EXPECTED IN THE AFTERNOON AS LOW LEVEL JET CRANKS UP TO THE SOUTH. COULD SEE A FEW STRONGER STORMS...WITH MODELS SHOWING CAPE OF 500-1000 J/KG AND 0-6 KM BULK SHEAR OF 40 TO 50 KNOTS. PLENTY OF MOISTURE TO WORK WITH AS WELL...WITH PRECIPITABLE WATER VALUES INCREASING TO AT LEAST 1.50 INCHES. SPC HAS KEPT THE DAY 2 SLIGHT RISK SOUTH OF THE WI/IL BORDER...WITH 5 PERCENT PROBS ACROSS MUCH OF THE FORECAST AREA. LATEST MESOSCALE MODEL SIMULATED REFLECTIVITY SEEMS TO AGREE WITH STRONGER AND MORE ORGANIZED CONVECTION SOUTH. THOUGH TEMPS ALOFT INCREASE TONIGHT INTO TOMORROW...KEPT HIGHS RIGHT AROUND 70 FOR TOMORROW...AS CLOUDS AND PRECIP WILL LIMIT HEATING. THURSDAY NIGHT THROUGH SATURDAY...FORECAST CONFIDENCE MEDIUM. CYCLOGENESIS IS EXPECTED THU NT FROM SW WI TO ERN LAKE SUPERIOR WITH COLD FROPA IN ITS WAKE. THE NOSE OF THE LOW LEVEL JET AND ASSOCIATED MOISTURE TRANSPORT WILL BOOST PWS TO 1.5 INCHES...WITH MUCAPE UP TO 500 J/KG. SFC-850 MB MOISTURE FLUX CONVERGENCE AND FRONTOGENESIS WILL BRING WIDESPREAD SHOWERS AND SCT TSTORMS FROM THU AFTERNOON INTO THE EVENING. SPC DAY 2 SLIGHT RISK REMAINS TO THE SOUTH BUT SOME STRONG STORMS ARE STILL POSSIBLE GIVEN DEEP LAYER SHEAR OF 40-50 KTS WITH THE AFOREMENTIONED AVAILABLE CAPE. THE COLD FROPA WILL OCCUR QUICKLY FROM W-E AFTER 06Z. AT LEAST LIGHT TO MODERATE RAIN SHOWERS WILL CONTINUE MUCH OF THE NIGHT AS AN UPPER WAVE WILL APPROACH FROM THE SW WHILE A MUCH STRONGER UPPER WAVE MOVES INTO MN. A LARGE POLAR TROUGH WILL BECOME ESTABLISHED OVER THE NORTH CENTRAL USA ON FRI...SLIGHTLY MOVING EWD ON SAT. LIGHT SHOWERS MAY LINGER FRI AM IN FAR ERN WI WHILE INSTABILITY SHOWERS MAY BE POSSIBLE FRI AFTERNOON. A SECONDARY COLD FRONT WILL THEN BRING GOOD CHANCES OF SHOWERS FRI NT...FOLLOWED BY SLIGHT CHANCES FOR INSTABILITY SHOWERS ONCE AGAIN ON SAT. STRONG COLD ADVECTION WILL KEEP TEMPS FALLING ON FRI WITH CHILLY CONDITIONS INTO SAT AS THE 925-850 MB COLD POOL MOVES ACROSS THE AREA. LONG TERM... SUNDAY THROUGH WEDNESDAY...FORECAST CONFIDENCE MEDIUM. THE LARGE POLAR TROUGH WILL SLOWLY LIFT NORTH INTO CANADA BY THE MIDDLE OF THE WEEK. BEFORE THEN...SHORTWAVE TROUGHS IN NW FLOW WILL BRING SMALL CHANCES OF SHOWERS AT TIMES. TEMPS WILL WARM EACH DAY BUT REMAIN BELOW NORMAL WITH THE EXCEPTION OF WED. AVIATION/00Z TAFS/... A FEW SHOWERS MAY AFFECT THE WESTERN HALF OF THE FORECAST AREA THROUGH LATE AFTERNOON...WITH SHOWERS LIKELY AND A FEW STORMS ALSO POSSIBLE LATER THIS EVENING AND OVERNIGHT. BASED ON MODEL GUIDANCE AND UPSTREAM OBS...MAY SEE LOWER CIGS MOVE IN OVERNIGHT. COULD ALSO SEE SOME PATCHY FOG. LOOKS MAINLY DRY THURSDAY MORNING...WITH MORE SHOWERS AND STORMS LIKELY THURSDAY AFTERNOON INTO THE NIGHT. LOWER CIGS AND VSBYS CERTAINLY POSSIBLE AT TIMES THROUGH THIS PERIOD. MARINE... COULD SEE A FEW WIND GUSTS APPROACH SMALL CRAFT ADVISORY LEVELS TONIGHT...BUT WINDS WILL GENERALLY STAY BELOW CRITERIA. WESTERLY WINDS FRIDAY WILL BE GUSTY BEHIND DEPARTING LOW PRESSURE. A SMALL CRAFT ADVISORY MAY EVENTUALLY BE NEEDED FOR THIS PERIOD. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...DAVIS TONIGHT/THURSDAY AND AVIATION/MARINE...DDV THURSDAY NIGHT THROUGH WEDNESDAY...GEHRING
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1021 AM CDT TUE SEP 30 2014 .UPDATE... LATEST MODEL SOUNDINGS INDICATE LOW LEVEL MOISTURE AND CLOUD COVER WILL PERSIST IN THE EAST WITH SOME AFTERNOON CLEARING TO SCATTERED OR BROKEN IN THE WESTERN AND SOUTH-CENTRAL CWA. EXPECTING CLOUDS TO FILL IN OVERNIGHT AHEAD OF THE NEXT SYSTEM APPROACHING FROM THE WEST. DRY CONDITIONS EXPECTED THROUGH WED MORNING. && .AVIATION/18Z TAFS/... WILL HANG ON TO STUBBORN LOW CLOUDS FOR MUCH OF TODAY...ESPECIALLY IN THE EAST. SOME AREAS MIGHT HANG ON TO MVFR CONDITIONS INTO WEDNESDAY. WILL EVALUATE 12Z GUIDANCE AND ADJUST TAFS ACCORDINGLY. DRY WEATHER IS EXPECTED TONIGHT THROUGH WEDNESDAY MORNING...WITH A CHANCE OF SHOWERS WEST IN THE AFTERNOON. && .PREV DISCUSSION... /ISSUED 349 AM CDT TUE SEP 30 2014/ SHORT TERM... TODAY...FORECAST CONFIDENCE MEDIUM SHORT WAVE RIDGING OVER THE STATE TODAY THROUGH MOST OF TONIGHT BETWEEN DEPARTING SHORT WAVE TROUGH OVER THE EASTERN GREAT LAKES AND ANOTHER LIFTING ALMOST DUE NORTH THROUGH THE DAKOTAS FROM WRN NEBRASKA. CLOUD COVER THE BIG PROBLEM TODAY WITH COLD AIR ADVECTION TRAPPING MOISTURE UNDER SUBSIDENCE INVERSION. NAM KEEPS CLOUDS OVER THE REGION ROUGHLY ALONG AND EAST OF A DELLS...MADISON TO JANESVILLE LINE THROUGH TONIGHT...WITH CLOUDS SCATTERING OUT MID-MORNING TO THE WEST. GFS KEEPS EASTERN THIRD UNDER THE CLOUDS...WITH HRRR HOLDING LOW CLOUDS JUST ALONG THE LAKE AFTER 17Z. WILL TREND CLOUDS WITH A BLEND...AS COLD AIR ADVECTION EASES LATER THIS MORNING WITH A SLIGHT UPWARD TREND IN 925 MB TEMPS THIS AFTERNOON. MARGINAL 850 MB/LAKE SURFACE TEMPERATURE DIFFERENTIAL DEVELOPING SOME SPRINKLES ALONG THE LAKE FROM SRN MILWAUKEE COUNTY SOUTH ON MKE TDWR BUT THESE SHOULD DIMINISH AS 850 MB TEMPS MODERATE LATER THIS MORNING. CLOUDS AND COOLEST 925 MB TEMPS KEEP HIGHS IN THE MID 50S NORTHEAST...RISING TO THE LOWER 60S SW WITH THE PROSPECT OF SOME SUNSHINE. TONIGHT...FORECAST CONFIDENCE MEDIUM. MODELS KEEP 700 MB OMEGA ALONG AND WEST OF THE MS RIVER WITH BETTER FORCING FOR ASCENT AHEAD OF APPROACHING SHORT WAVE AS FORECAST AREA REMAINS UNDER INFLUENCE OF DEPARTING SURFACE HIGH. WILL NOT BRING POPS INTO CWA THROUGH 12Z WEDNESDAY. LIGHT WINDS AND EXPECTED REDUCTION IN CLOUD COVER WILL ALLOW LOWS TO FALL INTO THE LOWER 40S EAST...WITH A BIT MORE MIXING AND WARMER 925 MB TEMPS HOLDING LOWS IN THE MID 40S WEST. LONG TERM... WEDNESDAY THROUGH FRIDAY...FORECAST CONFIDENCE MEDIUM. FLOW WILL SWITCH TO THE SOUTHWEST DURING THE MIDDLE OF THE WEEK AS A HIGH AMPLITUDE UPPER TROUGH SLIDES ACROSS THE U.S.. AN AMPLE AMOUNT OF MOISTURE WILL BE TAPPED FOR THIS SYSTEM. PRECIPITABLE WATER VALUES UP TO 1.5 INCHES ARE POSSIBLE WHICH IS VERY HIGH FOR THIS TIME OF YEAR. THE FIRST WEAK SHORTWAVE TROUGH WILL SWING THROUGH SOUTHERN WI ON WED...BUT LESS CONFIDENCE ABOUT ENOUGH FORCING OR MOISTURE WITH THIS INITIAL ROUND TO ALLOW FOR PRECIP. THE NEXT STRONGER SHORTWAVE TROUGH AND ASSOCIATED NOSE OF THE LOW LEVEL JET WILL ARRIVE THU AFTERNOON. GIVEN THE FORCING AND STEEPER MID LEVEL LAPSE RATES... CAPE SHOULD BE AROUND 1000 J/KG AND ALLOW FOR THUNDER. THE NAM SUGGESTS A BREEZY DAY ON THU GIVEN THE TIGHT PRESSURE GRADIENT... WHILE OTHER MODELS ARE MORE RESERVED. I LEANED TOWARD THE HIGHER WINDS GIVEN THE SYNOPTIC SETUP. TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF HOW MUCH SUN WILL PEEK THROUGH WHILE SOUTHERN WI IS WITHIN THE WARM SECTOR THU AFTERNOON OR IF THE RAIN WILL KEEP THINGS COOLER. THERE IS FAIRLY GOOD AGREEMENT THAT THE COLD FRONT WILL HOLD OFF UNTIL THU EVENING...SO I KEPT TEMPS ON THE WARM SIDE WITH THE MODEL CONSENSUS. SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM. THE CENTER OF THE MID LEVEL UPPER LOW AND ASSOCIATED VORT MAX IS EXPECTED TO BARREL THROUGH SOUTHERN WI FRI MORNING. THEN THE UPPER TROUGH COULD HANG AROUND THE GREAT LAKES REGION THROUGH THE WEEKEND. IT IS LOOKING LIKE A COOL AND CLOUDY WEEKEND WITH THE POSSIBILITY FOR SOME LIGHT RAIN SHOWERS. AVIATION/12Z TAFS/... MVFR CLOUD DECK WILL HOLD THROUGH AT LEAST MID-MORNING. QUESTION THEN IS WHEN/IF DECK SCATTERS OUT/LIFTS TO VFR. ALL GUIDANCE IS TOO LOW WITH CURRENT STRATUS DECK BUT LEANING TOWARD MORE OPTIMISTIC GFS/HRRR WHICH WILL SCATTER OUT AT KMSN AROUND 16Z-17Z...AND EASTERN TAF SITES IN THE MID-AFTERNOON WHERE MOISTURE OFF THE LAKE WILL SLOW IMPROVEMENT. GUSTY WINDS WILL DIMINISH THROUGH THE MORNING INTO THE AFTERNOON AS GRADIENT WEAKENS WITH HIGH NOSING DOWN INTO REGION. WILL HAVE TO WATCH FOR FOG POTENTIAL EAST AS ONSHORE FLOW BRINGS LAKE MOISTURE INLAND. MARINE... CURRENT END TIME FOR SMALL CRAFT ADVISORY LOOKS GOOD AS WINDS ARE SLOWLY LOWERING AND SHOULD CONTINUE TO EASE AS HIGH NOSES INTO REGION. WAVES SHOULD BE 4 FEET OR LESS BY 18Z. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR LMZ643>646. && $$ UPDATE...SM/DDV TODAY/TONIGHT AND AVIATION/MARINE...REM WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
349 AM CDT TUE SEP 30 2014 .SHORT TERM... TODAY...FORECAST CONFIDENCE MEDIUM SHORT WAVE RIDGING OVER THE STATE TODAY THROUGH MOST OF TONIGHT BETWEEN DEPARTING SHORT WAVE TROUGH OVER THE EASTERN GREAT LAKES AND ANOTHER LIFTING ALMOST DUE NORTH THROUGH THE DAKOTAS FROM WRN NEBRASKA. CLOUD COVER THE BIG PROBLEM TODAY WITH COLD AIR ADVECTION TRAPPING MOISTURE UNDER SUBSIDENCE INVERSION. NAM KEEPS CLOUDS OVER THE REGION ROUGHLY ALONG AND EAST OF A DELLS...MADISON TO JANESVILLE LINE THROUGH TONIGHT...WITH CLOUDS SCATTERING OUT MID-MORNING TO THE WEST. GFS KEEPS EASTERN THIRD UNDER THE CLOUDS...WITH HRRR HOLDING LOW CLOUDS JUST ALONG THE LAKE AFTER 17Z. WILL TREND CLOUDS WITH A BLEND...AS COLD AIR ADVECTION EASES LATER THIS MORNING WITH A SLIGHT UPWARD TREND IN 925 MB TEMPS THIS AFTERNOON. MARGINAL 850 MB/LAKE SURFACE TEMPERATURE DIFFERENTIAL DEVELOPING SOME SPRINKLES ALONG THE LAKE FROM SRN MILWAUKEE COUNTY SOUTH ON MKE TDWR BUT THESE SHOULD DIMINISH AS 850 MB TEMPS MODERATE LATER THIS MORNING. CLOUDS AND COOLEST 925 MB TEMPS KEEP HIGHS IN THE MID 50S NORTHEAST...RISING TO THE LOWER 60S SW WITH THE PROSPECT OF SOME SUNSHINE. .TONIGHT...FORECAST CONFIDENCE MEDIUM. MODELS KEEP 700 MB OMEGA ALONG AND WEST OF THE MS RIVER WITH BETTER FORCING FOR ASCENT AHEAD OF APPROACHING SHORT WAVE AS FORECAST AREA REMAINS UNDER INFLUENCE OF DEPARTING SURFACE HIGH. WILL NOT BRING POPS INTO CWA THROUGH 12Z WEDNESDAY. LIGHT WINDS AND EXPECTED REDUCTION IN CLOUD COVER WILL ALLOW LOWS TO FALL INTO THE LOWER 40S EAST...WITH A BIT MORE MIXING AND WARMER 925 MB TEMPS HOLDING LOWS IN THE MID 40S WEST. .LONG TERM... WEDNESDAY THROUGH FRIDAY...FORECAST CONFIDENCE MEDIUM. FLOW WILL SWITCH TO THE SOUTHWEST DURING THE MIDDLE OF THE WEEK AS A HIGH AMPLITUDE UPPER TROUGH SLIDES ACROSS THE U.S.. AN AMPLE AMOUNT OF MOISTURE WILL BE TAPPED FOR THIS SYSTEM. PRECIPITABLE WATER VALUES UP TO 1.5 INCHES ARE POSSIBLE WHICH IS VERY HIGH FOR THIS TIME OF YEAR. THE FIRST WEAK SHORTWAVE TROUGH WILL SWING THROUGH SOUTHERN WI ON WED...BUT LESS CONFIDENCE ABOUT ENOUGH FORCING OR MOISTURE WITH THIS INITIAL ROUND TO ALLOW FOR PRECIP. THE NEXT STRONGER SHORTWAVE TROUGH AND ASSOCIATED NOSE OF THE LOW LEVEL JET WILL ARRIVE THU AFTERNOON. GIVEN THE FORCING AND STEEPER MID LEVEL LAPSE RATES... CAPE SHOULD BE AROUND 1000 J/KG AND ALLOW FOR THUNDER. THE NAM SUGGESTS A BREEZY DAY ON THU GIVEN THE TIGHT PRESSURE GRADIENT... WHILE OTHER MODELS ARE MORE RESERVED. I LEANED TOWARD THE HIGHER WINDS GIVEN THE SYNOPTIC SETUP. TEMPERATURES WILL BE TRICKY DUE TO THE UNCERTAINTY OF HOW MUCH SUN WILL PEEK THROUGH WHILE SOUTHERN WI IS WITHIN THE WARM SECTOR THU AFTERNOON OR IF THE RAIN WILL KEEP THINGS COOLER. THERE IS FAIRLY GOOD AGREEMENT THAT THE COLD FRONT WILL HOLD OFF UNTIL THU EVENING...SO I KEPT TEMPS ON THE WARM SIDE WITH THE MODEL CONSENSUS. SATURDAY THROUGH MONDAY...FORECAST CONFIDENCE MEDIUM. THE CENTER OF THE MID LEVEL UPPER LOW AND ASSOCIATED VORT MAX IS EXPECTED TO BARREL THROUGH SOUTHERN WI FRI MORNING. THEN THE UPPER TROUGH COULD HANG AROUND THE GREAT LAKES REGION THROUGH THE WEEKEND. IT IS LOOKING LIKE A COOL AND CLOUDY WEEKEND WITH THE POSSIBILITY FOR SOME LIGHT RAIN SHOWERS. && .AVIATION/12Z TAFS/... MVFR CLOUD DECK WILL HOLD THROUGH AT LEAST MID-MORNING. QUESTION THEN IS WHEN/IF DECK SCATTERS OUT/LIFTS TO VFR. ALL GUIDANCE IS TOO LOW WITH CURRENT STRATUS DECK BUT LEANING TOWARD MORE OPTIMISTIC GFS/HRRR WHICH WILL SCATTER OUT AT KMSN AROUND 16Z-17Z...AND EASTERN TAF SITES IN THE MID-AFTERNOON WHERE MOISTURE OFF THE LAKE WILL SLOW IMPROVEMENT. GUSTY WINDS WILL DIMINISH THROUGH THE MORNING INTO THE AFTERNOON AS GRADIENT WEAKENS WITH HIGH NOSING DOWN INTO REGION. WILL HAVE TO WATCH FOR FOG POTENTIAL EAST AS ONSHORE FLOW BRINGS LAKE MOISTURE INLAND. && .MARINE... CURRENT END TIME FOR SMALL CRAFT ADVISORY LOOKS GOOD AS WINDS ARE SLOWLY LOWERING AND SHOULD CONTINUE TO EASE AS HIGH NOSES INTO REGION. WAVES SHOULD BE 4 FEET OR LESS BY 18Z. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT THIS AFTERNOON FOR LMZ643>646. && $$ TODAY/TONIGHT AND AVIATION/MARINE...REM WEDNESDAY THROUGH MONDAY...MRC
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1156 PM MDT MON SEP 29 2014 .UPDATE... ISSUED AT 955 PM MDT MON SEP 29 2014 IT WAS AN ACTIVE AFTERNOON AND EVENING ACROSS MUCH OF THE CWA AS A INTENSE LOW PRESSURE SYSTEM MOVED ACROSS CENTRAL AND NORTHERN COLORADO. A COLD FRONT SWEEPING OUT AHEAD OF THE LOW INTO A MOIST AND UNSTABLE AIR MASS COMBINED WITH VERY STRONG WINDS ALOFT PRODUCED STRONG TO SEVERE TSTORMS WITH LARGE HAIL AND DAMAGING WINDS. PING PONG BALL SIZE HAIL WAS REPORTED WITH A TSTORM SOUTH OF ALLIANCE EARLIER THIS EVENING. WITH THE SQUALL LINE EAST OF OUR PANHANDLE COUNTIES...THE TORNADO WATCH WAS ALLOWED TO EXPIRE AT 9 PM. ISOLATED TSTORMS WILL CONTINUE TONIGHT EAST OF THE LARAMIE RANGE...WITH SOME HEAVIER RAIN SHOWERS FOR WESTERN NEBRASKA PANHANDLE WHERE A FLOOD WATCH REMAINS IN EFFECT FOR ANOTHER ONE TO TWO INCHES OF RAIN ATOP ONE TO THREE INCHES THAT FELL LAST NIGHT AND THIS MORNING. AS THE SURFACE LOW DEEPENS OVER WESTERN NEBRASKA LATE TONIGHT AND EARLY TUESDAY MORNING... STRONG WEST WINDS WILL DEVELOP ACROSS MUCH OF SOUTHEAST WYOMING. 700MB WINDS PEAK AROUND 65 KT BETWEEN CHEYENNE AND RAWLINS AND THE COLORADO BORDER AND WHEATLAND. A HIGH WIND WARNING REMAINS IN EFFECT FROM MIDNIGHT TONIGHT THROUGH NOON TUESDAY. FINALLY... ENOUGH COLD AIR BEHIND THIS SYSTEM TO LOWER SNOW LEVELS TO 8500 FT OVER THE SNOWY AND SIERRA MADRE RANGES TONIGHT AND TUESDAY MORNING FOR LIGHT SNOW ACCUMULATIONS. UPDATED ZONES ALREADY SENT. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 315 PM MDT MON SEP 29 2014 CONVECTIVE LINE WAS ALREADY DEVELOPING THIS AFTERNOON EXTENDING FROM ROCK RIVER SSE TOWARDS THE DENVER METRO AREA. ATMOSPHERIC DESTABILIZATION ALBEIT WEAK HAS BEEN UNDERWAY BEHIND THE MORNING CONVECTION AND AHEAD OF THIS SECONDARY CONVECTIVE LINE. ALTHOUGH LINGERING CLOUD COVER HAS INHIBITED IT SOME. 21Z SFC ANALYSIS PLACED THE 1003MB LOW SOUTH OF PUEBLO WITH PRESSURE FALLS TO THE NORTH ALONG THE I25 CORRIDOR TOWARDS DENVER. LATEST SPC MESOANALYSIS SHOWED 1000 J/KG OF SBCAPE NOSING INTO THE SRN NEBRASKA PANHANDLE AS A BAND OF 40-50 KNOTS OF DEEP LAYER SHEAR APPROACHED FROM THE SOUTHWEST. INCREASINGLY FAVORABLE DEEP LAYER SHEAR WERE ASSOCIATED WITH A POWERFUL LOW PRESSURE AREA THAT SATELLITE PIX SHOWED WAS LIFTING NORTHEAST FROM THE FOUR CORNERS AREA. THIS FEATURE WILL LIFT INTO COLORADO BY 6 PM BEFORE CLOSING OFF NR THE WY/NE STATE LINE BY MIDNIGHT. THE AFOREMENTIONED SFC LOW NOW LOCATED NR PUEBLO WILL LIFT NORTH INTO THE WRN NEBRASKA PANHANDLE THIS EVENING AND DEEPEN TO 993MB BY TUESDAY MORNING. AS IT DOES SO...LLVL SOUTHEAST FLOW COMBINED WITH AN APPROACHING MID/UPPER-LEVEL SPEED MAX TO DRAW A FAVORABLY SHEARED ENVIRONMENT...ESPECIALLY THROUGH THE EARLY THIS EVENING. LATEST HRRR HAS DONE WELL WITH CONVECTIVE INITIATION SO FAR AND SUGGESTS THE SEVERE POTENTIAL TO BE GREATEST WHILE STORM MODES ARE DISCRETE...WITH EVEN A FEW ROTATING UPDRAFTS CONTAINING LARGE HAIL...DAMAGING WINDS AND EVEN AN ISOLATED TORNADO POSSIBLE. THIS WILL ESPECIALLY BE THE CASE FROM EASTERN LARAMIE COUNTY EAST TO SIDNEY. BY EARLY/MID-EVENING SEVERE POTENTIAL WILL DROP OFF QUICKLY AS CONVECTION BECOMES A MORE HOMOGENEOUS AREA OF MODERATE TO LOCALLY HEAVY RAINFALL...WHICH WILL CONTINUE INTO TUESDAY MORNING. MANY OF THESE AREAS OVR THE WRN NEBRASKA PANHANDLE RECEIVED 1-2 INCHES THIS MORNING AND WITH ANOTHER AT LEAST 1-2 INCHES ON ITS WAY OVERNIGHT. THE FLOOD WATCH FOR THE WRN NEBRASKA PANHANDLE WILL CONTINUE TO BE WARRANTED TONIGHT. THE OTHER CONCERN ASSOCIATED WITH THIS DEEPENING LOW PRESSURE AREA IS ITS IMPACT ON WINDS. SW/NE ORIENTED GRADIENTS TIGHTEN SIGNIFICANTLY AFTER MIDNIGHT CONTINUING THRU TUESDAY MORNING. ALTHOUGH A MARGINAL EVENT...THIS PUTS THE WIND PRONE AREAS IN SE WYOMING UNDER THE GUN. EVEN THOUGH KCAG-KCPR GRADIENTS ARE A BIT MARGINAL...H7 PROGS CONTINUE TO POINT TO THE POTENTIAL FOR A HIGH WIND SET-UP EARLY TUESDAY. WILL KEEP THE HIGH WIND WARNING GOING AS INHERITED. WRAPAROUND MOISTURE WILL CONTINUE FOR A TIME NR THE PINE RIDGE TUESDAY MORNING...BEFORE FINALLY LIFTING NORTHEAST BY MIDDAY. FLOW WILL WESTERLY FOR TUESDAY...BUT THE CWFA WILL STILL BE INFLUENCED BY THE LONGWAVE TROF OVER THE ROCKIES. A FEW SHOWERS AND ISOLATED THUNDERSTORMS WILL STILL BE POSSIBLE...ESPECIALLY WEST OF THE LARAMIE RANGE...ALTHOUGH COVERAGE WILL BE LESS. THE NEXT FAST MOVING SHORTWAVE TROUGH WILL DIVE SOUTHEAST THRU THE CWFA FOR WEDNESDAY. THIS WILL PROVIDE ANOTHER CHANCE FOR SHOWERS AND THUNDERSTORMS...ESPECIALLY OVR THE SOUTHEAST WYOMING MOUNTAINS AND ADJACENT VALLEYS AND PLAINS. TEMPERATURES WILL WARM SLIGHTLY ON TUESDAY...BACK INTO THE 60S MOST LOCATIONS WITH ANOTHER COOL DOWN INTO THE 50S ANTICIPATED FOR WEDNESDAY. .LONG TERM...(THURSDAY THROUGH SUNDAY) ISSUED AT 315 PM MDT MON SEP 29 2014 PRETTY QUIET EXTENDED PERIOD WITH PERSISTENT DRY NORTHWESTERLY FLOW ALOFT IN PLACE. SHORTWAVE WILL MOVE SOUTHEASTWARD FROM EASTERN MONTANA INTO THE DAKOTAS DURING THE DAY ON THURS. NO PRECIP IS EXPECTED WITH THIS FEATURE AS IT WELL TO THE NORTHEAST. TEMPS WILL BE SLIGHTLY BELOW NORMAL ON THURS WITH 700MB TEMPS AROUND 0C. A WARMING TREND WILL BEGIN ON FRI AND THEN CONTINUE INTO THE WEEKEND WITH 700MB TEMPS RISING TO 5-10C. ALTHOUGH THE STRONGEST FLOW ALOFT IS OVER WESTERN SOUTH DAKOTA ON THURS THROUGH SUN...IT WILL STILL BE BREEZY DURING THE AFTERNOONS ESPECIALLY ACROSS SOUTHEAST WY WITH GOOD MIXING IN PLACE. EXPECT WEST TO NORTHWEST WIND GUSTS TO 25-30 KT ON MOST AFTNS. PRECIP CHANCES AND CLOUD COVER WILL BE VERY LIMITED THROUGH THE PERIOD WITH GENERAL RIDGING OVER THE INTERMOUNTAIN WEST AND A LACK OF MOISTURE. && .AVIATION...(FOR THE 06Z TAFS THROUGH TUESDAY AFTERNOON) WIDESPREAD MODERATE TO HEAVY RAIN WITH EMBEDDED TSTMS WILL CONTINUE ACROSS AREAS TO THE EAST OF THE LARAMIE RANGE THROUGH TONIGHT. EXPECT PREVAILING IFR VIS IN THE RAIN. CDR WILL ALSO ALSO SEE SOME LIFR CIGS THROUGH AROUND 03Z. THE RAIN WILL GRADUALLY BEGIN TO TAPER OFF AFTER 03Z OVER SOUTHEAST WY AND AFTER 06Z IN THE WESTERN NEBRASKA PANHANDLE. A COLD FRONT WILL PASS OVER THE AREA LATER TONIGHT WITH WINDS BECOMING WESTERLY AND GUSTY. GUSTS TO 30-35 KT WILL BE COMMON THROUGH TUES AFTERNOON...ESPECIALLY ACROSS SOUTHEAST WY. && .FIRE WEATHER... ISSUED AT 315 PM MDT MON SEP 29 2014 A STRONG AREA OF LOW PRESSURE WILL LIFT NORTHEAST FROM THE FOUR CORNERS INTO THE DISTRICTS THROUGH TONIGHT. THIS SYSTEM WILL BE BRING WIDESPREAD WETTING RAINS TO A LARGE PART OF THE DISTRICT...ESPECIALLY EAST OF THE LARAMIE RANGE. SOME AREAS IN THE WESTERN NEBRASKA PANHANDLE PICKED UP 1-2 INCHES OF RAIN THIS MORNING AND ARE IN LINE FOR ANOTHER 1-2 INCHES...PERHAPS LOCALLY HIGHER TONIGHT AND EARLY TUESDAY. A FLOOD WATCH HAS BEEN ISSUED FOR THE WESTERN NEBRASKA PANHANDLE THROUGH NOON TUESDAY. WIND PRONE AREAS WEST OF THE LARAMIE RANGE WILL BECOME VERY WINDY LATE TONIGHT AND EARLY TUESDAY...WHERE A HIGH WIND WARNING IS IN EFFECT. THE COOL AND UNSETTLED WEATHER WILL CONTINUE TUESDAY AND WEDNESDAY...THOUGH COVERAGE AND INTENSITY WILL BE LIGHTER. TEMPERATURES WILL BEGIN WARMING UP FOR THE END OF THE WEEK AND UPCOMING WEEKEND. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...HIGH WIND WARNING UNTIL NOON MDT TUESDAY FOR WYZ106-110-116-117. NE...FLOOD WATCH THROUGH TUESDAY MORNING FOR NEZ002-003-019>021-054- 055-095-096. && $$ UPDATE...JAMSKI SHORT TERM...HAHN LONG TERM...FINCH AVIATION...FINCH FIRE WEATHER...HAHN
AREA FORECAST DISCUSSION
NWS ALBANY NY
421 AM EDT THU OCT 2 2014 .SYNOPSIS... ALONG WITH A FEW MORNING SPRINKLES AND AREAS OF FOG...CLOUDS WILL EVENTUALLY BREAK FOR SUNSHINE TODAY AS AN UPPER LEVEL STORM OVER NEW ENGLAND CONTINUES TO MOVE EASTWARD AND AWAY FROM THE REGION. DRY AND WARM CONDITIONS ARE EXPECTED ON FRIDAY...BEFORE A COLD FRONT BRINGS GUSTY RAIN SHOWERS AND COOLER TEMPERATURES TO THE REGION FOR THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 420 AM EDT...AN UPPER LEVEL LOW IS SITUATED JUST SOUTHEAST OF THE AREA NEAR CAPE COD. AS THIS SYSTEM SLOWLY SLIDES EASTWARD...IT IS PULLING MOISTURE OFF THE ATLANTIC OCEAN AND PRODUCING SHOWERS ACROSS PARTS OF MASSACHUSETTS AND CONNECTICUT. WITH THESE SHOWERS WRAPPING AROUND THE UPPER LEVEL LOW WITHIN THE BROAD EASTERLY FLOW ALOFT...THEY ARE TRACKING INTO PARTS OF SRN VT...THE BERKSHIRES...AND LITCHFIELD HILLS THIS MORNING. A FEW ADDITIONAL RAIN SHOWERS OR AREAS OF DRIZZLE ARE EXPECTED OVER THE NEXT FEW HOURS...BEFORE THE UPPER LEVEL LOW SHIFTS FAR ENOUGH EASTWARD TO KEEP ANY PRECIP EAST OF OUR AREA AND CONFINED TO CENTRAL AND EASTERN NEW ENGLAND. THE 3KM HRRR SHOWS THIS HAPPENED BY ABOUT 8 AM...SO WILL DROP ALL POPS OVER WESTERN NEW ENGLAND BY THE MID MORNING HOURS. IN ADDITION TO THE RAIN SHOWERS IS PLENTY OF LOW CLOUDS /STRATUS/ AND AREAS OF FOG. WITH A LOW LEVEL INVERSION IN PLACE TODAY...IT WILL TAKE A WHILE FOR THIS LOW LEVEL MOISTURE TO BECOME MIXED OUT. AS A RESULT...WE CAN EXPECT MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY...WITH CLOUDS EVENTUALLY BREAKING FOR INCREASING AMOUNTS OF SUN DURING THE AFTN. THE EXCEPTION WILL BE ACROSS THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS...WHERE THE CLOUDS CURRENTLY AREN/T AS THICK...AND MORE SUN CAN BE EXPECTED THIS MORNING. MAX TEMPS TODAY WILL RANGE FROM THE LOW 60S TO LOW 70S...WITH THE WARMEST ACROSS WESTERN AREAS. TEMPS IN THE CAPITAL REGION/HUDSON VALLEY LOOK TO TOP OUT IN THE UPPER 60S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... A BRIEF AREA OF UPPER LEVEL RIDGING WILL BUILD INTO THE AREA FOR TONIGHT INTO FRIDAY. THIS WILL ALLOW FOR CONTINUED CLEARING SKIES OVERNIGHT...ALTHOUGH SOME PATCHY FOG WILL DEVELOP THANKS TO THE GOOD RADIATIONAL COOLING CONDITIONS. MIN TEMPS TONIGHT WILL MAINLY BE IN THE 40S TO NEAR 50. PARTLY TO MOSTLY SUNNY SKIES ARE EXPECTED ON FRIDAY...WITH THE MOST CLOUDS ACROSS THE ADIRONDACKS. WITH 850 HPA TEMPS AROUND 10 TO 11 DEGREES C...ABOVE NORMAL TEMPS CAN BE EXPECTED...WITH HIGHS IN THE MID 60S TO MID 70S ACROSS THE AREA. A STRONG COLD FRONT WILL BE MOVING TOWARDS THE AREA FOR FRIDAY NIGHT INTO SATURDAY. MOST OF THE FRIDAY NIGHT SHOULD BE DRY...ALTHOUGH WESTERN AREAS WILL START TO SEE SOME SHOWERS BY LATER IN THE NIGHT. MIN TEMPS FRI NIGHT WILL BE IN THE 50S. THIS FRONT WILL BE ACCOMPANIED BY A DEEPENING TROUGH THAT WILL TAKE ON A NEGATIVE TILT FOR SATURDAY. AHEAD OF THIS FRONT...A STRONG LOW LEVEL JET OF 50 KNOTS /ABOUT 3 TO 5 STD ABOVE NORMAL ACCORDING TO THE 850 HPA V WINDS ON THE 00Z GEFS/ WILL BE IN PLACE...ALLOWING FOR PLENTY OF MOISTURE TO WORK ITS WAY INTO THE REGION. PWATS WILL EXCEED 1.50 INCHES OVER MUCH OF THE AREA...WHICH IS ABOUT 2-3 STD ABOVE NORMAL FOR THIS TIME OF YEAR. AS A RESULT...A LINE OF MODERATE TO HEAVY RAIN SHOWERS WILL PRECEDE AND ACCOMPANY THE FRONTAL PASSAGE. A WEAK WAVE OF LOW PRESSURE MAY DEVELOP ON THE FRONT AS WELL...WHICH MAY SLOW DOWN THE FRONT/S PROGRESS AS WELL...ALLOWING FOR A PROLONGED PERIOD OF RAINFALL. THIS SHOULD ALLOW FOR ABOUT A HALF INCH TO ONE INCH OF RAIN ACROSS THE ENTIRE REGION FOR SATURDAY. SOME GUSTY WINDS WILL ACCOMPANY THE SHOWERS AS WELL DUE TO THE STRONG DYNAMICS IN PLACE. WE WON/T MENTION THUNDER AT THIS TIME...AS INSTABILITY LOOKS TO BE LACKING. WITH THE CLOUDS/SHOWERS...IT WILL BE COOLER THAN FRIDAY...WITH HIGHS IN THE UPPER 50S TO LOW 60S. THE FRONT SHOULD BE THROUGH MOST OF THE AREA BY THE EVENING HOURS...ALLOWING FOR COOLER AND DRIER AIR TO WORK INTO THE REGION. WITH MUCH COOLER AIR ALOFT...SOME ADDITIONAL CYCLONIC FLOW/LAKE ENHANCED RAIN SHOWERS WILL BE POSSIBLE DOWNWIND OF LAKE ONTARIO FOR SAT NIGHT. OTHERWISE...SHOWERS WILL BE ENDING...WITH DECREASING CLOUDS THROUGH THE OVERNIGHT HOURS. MIN TEMPS WILL RANGE FROM THE MID 30S TO MID 40S. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... A MEAN UPPER TROUGH WILL CONTINUE OVER EASTERN NORTH AMERICA WITH THE AXIS WEST OF OUR REGION...PUTTING OUR REGION IN THE WEST TO SOUTHWEST UPPER FLOW PORTION OF THE MEAN UPPER TROUGH. ANY LINGERING SHOWERS FROM THE EXITING COLD FRONT WILL EXIT SUNDAY MORNING...BUT RAPIDLY COOLING BOUNDARY LAYER TEMPERATURES AND LOW LEVEL WINDS OFF THE GREAT LAKES...SOME SCATTERED SHOWERS COULD EXTEND FROM THE LAKES INTO THE SOUTHERN ADIRONDACKS SUNDAY AND SUNDAY NIGHT. HIGHS SUNDAY IN THE 50S TO LOWER 60S. SOME DISAGREEMENTS IN GUIDANCE/ENSEMBLES AS TO ANOTHER UPPER IMPULSE...BASED MORE IN THE NORTHERN STREAM...POSSIBLY TRACKING AROUND THE SOUTHERN PERIPHERY OF THE UPPER TROUGH AND THROUGH OUR REGION LATER MONDAY THROUGH TUESDAY...WITH MORE SCATTERED SHOWERS AND SOME BOUNDARY LAYER WARMING AS THE UPPER TROUGH AXIS RETROGRADES A LITTLE. THERE IS A LOOSE CONSENSUS IN SOME WARMING AND RETROGRADING OF THE UPPER TROUGH...THE DISAGREEMENTS ARE WHETHER WE GET LITTLE TO NO COVERAGE OF SHOWERS OR BETTER COVERAGE OF SHOWERS...DEPENDING ON THE PRESENCE OR NON PRESENCE OF WELL DEFINED UPPER DYNAMICS. FOR NOW...INDICATING JUST CHANCES FOR SHOWERS...BUT THE DETAILS HOW MUCH POTENTIAL FOR RAIN TUESDAY WILL GET CLEARER AS WE GET NEARER TO NEXT WEEK. HIGHS MONDAY IN THE UPPER 50S TO MID 60S. HIGHS TUESDAY IN THE UPPER 60S TO AROUND 70...WITH LOWER 60S HIGHER ELEVATIONS. THERE ARE ALSO CONFLICTS IN GUIDANCE/ENSEMBLES AS TO WHETHER ANOTHER UPPER IMPULSE AND THE LEADING EDGE OF COOLER AIR ARRIVES WEDNESDAY. THE RAPID UPPER FLOW PATTERN IS DIFFICULT FOR LONG RANGE GUIDANCE TO RESOLVE. SO...JUST INDICATING SHOWERS EXITING TUESDAY NIGHT AND WEDNESDAY WITH HIGHS WEDNESDAY IN THE MID TO UPPER 60S...SOME UPPER 50S HIGHER ELEVATIONS. && .AVIATION /08Z THURSDAY THROUGH MONDAY/... WITH A SURFACE LOW PASSING WELL TO OUR SOUTH AND AN UPPER LEVEL LEVEL LOW EXITING THE REGION HAVE LOTS OF CLOUDS AND LOW LEVEL MOISTURE IN PLACE. SOME SHOWERS AND DRIZZLE WILL LINGER THROUGH THE EARLY MORNING HOURS AT KALB AND KPSF WITH CHANCES DECREASING TOWARD DAYBREAK. CLOUDS HEIGHTS WILL BE JUST ABOVE 3000 FEET AT KGFL BUT TRENDING DOWNWARD TO MVFR BETWEEN 06Z-12Z AND REMAIN MVFR THROUGH ABOUT 18Z. CEILINGS WILL VARY BETWEEN IFR AND VFR PERIODICALLY AT KALB THROUGH ABOUT 12Z. CEILINGS IN THE MVFR RANGE AT KPOU AND KPSF SHOULD REMAIN IN THE MVFR RANGE THROUGH ABOUT 20Z-22Z. VISIBILITIES SHOULD BE MOSTLY VFR WITH ANY RAIN BEING VERY LIGHT THROUGH THE EARLY MORNING HOURS. SOME MVFR VISIBILITIES ARE LIKELY AT KALB AND KGFL AFTER 10Z...ESPECIALLY IF THERE IS SOME PARTIAL CLEARING...WHICH IS NOT TOO FAR WEST OF THE TAF SITES CURRENTLY. SOME INTERVALS OF MVFR VISIBILITIES ARE POSSIBLE AT KPSF AND KPOU...KPSF WITH POSSIBLE LIGHT RAIN AND KPOU WITH SOME POSSIBLE PARTIAL CLEARING. IT SHOULD BE MENTIONED THAT CURRENT TRENDS IN SATELLITE AND RADAR SUGGEST ANY CLEARING WILL TAKE QUITE SOME TIME TO SPREAD EAST...EVEN THOUGH IT IS INTO THE SOUTHERN ADIRONDACKS...AND CENTRAL/WESTERN MOHAWK VALLEY. ONCE THE SYSTEM EXITS...CEILINGS SHOULD LIFT ABOVE 3000 FEET AFTER 18Z-22Z AND REMAIN VFR THROUGH THIS EVENING. HOWEVER...IFR CONDITIONS ARE EXPECTED AT KPSF FOR A GOOD CHUNK OF THE OVERNIGHT. GRADUALLY IMPROVEMENT ON THURSDAY WITH VFR DEVELOPING DURING THE AFTERNOON AS THE UPPER LEVEL MOVES OFF TO THE EAST AND RIDGING BUILDS IN. LIGHT TO CALM WINDS THROUGH DAYBREAK WITH A LIGHT N-NE FLOW AT LESS THAN 6 KT SHIFTING TO E-SE AS THE DAY PROGRESSES THURSDAY...TRENDING BACK TO VARIABLE/CALM DURING THE EVENING. OUTLOOK... FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY: HIGH OPERATIONAL IMPACT. DEFINITE SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY THROUGH MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ALONG WITH SOME AREAS OF MORNING FOG...WIDESPREAD CLOUD COVER IS EXPECTED THROUGH AT LEAST THIS MORNING. THERE MAY BE A FEW SPRINKLES EARLY THIS MORNING ACROSS FAR EASTERN AREAS AS WELL. RH VALUES WILL DROP TO 50 TO 60 PERCENT THIS AFTERNOON WITH LIGHT EASTERLY WINDS. RH VALUES WILL RECOVER TO 90 TO 100 PERCENT TONIGHT WITH FOG AND DEW FORMATION AND NEARLY CALM WINDS. AFTER MORNING FOG BURNS OFF TOMORROW...MOSTLY SUNNY SKIES ARE EXPECTED THROUGH MUCH OF THE DAY FRIDAY WITH RH VALUES DROPPING TO 45 TO 50 PERCENT IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL BE 5 TO 10 MPH ON FRIDAY. A WIDESPREAD WETTING RAINFALL IS EXPECTED ON SATURDAY. && .HYDROLOGY... A DEPARTING UPPER LEVEL LOW WILL ALLOW FOR A FEW LIGHT RAIN SHOWERS OR SPRINKLES EARLY THIS MORNING ACROSS NEW ENGLAND. OTHERWISE...DRY WEATHER IS ANTICIPATED FOR TODAY THROUGH TOMORROW EVENING. WITH A COLD FRONT CROSSING THE REGION...A WIDESPREAD RAINFALL IS EXPECTED BETWEEN LATE FRIDAY NIGHT AND SATURDAY. MOST AREAS WILL SEE BETWEEN ONE HALF INCH AND ONE INCH OF RAINFALL. ASIDE FROM SOME PUDDLES ON ROADWAYS...THIS RAINFALL WILL NOT CAUSE ANY HYDROLOGIC ISSUES...AND WILL BE BENEFICIAL TO THE REGION. MAINLY DRY...BUT MUCH COOLER....WEATHER IS EXPECTED FOR SUNDAY INTO MONDAY. OVERALL...AREA RIVERS AND STREAMS LOOK TO MAINLY HOLD STEADY OR ONLY SLIGHTLY RISE THROUGH THE WEEKEND. 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...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MIAMI FL
133 AM EDT THU OCT 2 2014 .AVIATION...VFR AND LIGHT OFFSHORE WINDS WILL PREVAIL THROUGH THIS MORNING. WINDS DO LOOK TO TURN ONSHORE AT THE ATLANTIC COAST TERMINALS (EXCEPT PERHAPS KTMB) AND THIS WILL HELP TO INITIATE SCATTERED TSTORM DEVELOPMENT. DUE TO THE ONLY SCATTERED COVERAGE EXPECTED, HAVE KEPT JUST VCTS FOR THE EAST COAST TERMINALS LATER THIS AFTERNOON. ANY IMPACTS OF MVFR OR IFR WOULD BE BRIEF SHOULD A TSTORM AFFECT ANY GIVEN TERMINAL. /GREGORIA && .PREV DISCUSSION... /ISSUED 916 PM EDT WED OCT 1 2014/ UPDATE... RADAR SHOWING CONVECTION HAS CONTINUED LATER INTO THE EVENING HOURS THAN PREVIOUSLY THOUGH. MUCH OF THE STRONGER CONVECTION LOOKS TO BE RUNNING ALONG A FRONTAL BOUNDARY THAT HAS DRIFTED A LITTLE SOUTH, AND IS SITTING JUST TO THE NORTH OF JUPITER. SO, HAVE BUMPED UP POPS FOR THE NEXT SEVERAL HOURS, AND ADDED SOME THUNDERSTORMS TO THE WEATHER THIS EVENING FOR THE ATLANTIC WATERS, AND PALM BEACH COAST. THE HRRR DOES CONTINUE TO INDICATE THIS SHOULD COME TO AN END OVER THE NEXT HOUR OR TWO. PREV DISCUSSION... /ISSUED 755 PM EDT WED OCT 1 2014/ AVIATION... THUNDERSTORMS ARE BECOMING ENHANCED ACROSS THE ATLANTIC WATERS ATTM SO KEPT VCTS THROUGH 02Z FOR ALL EAST COAST TERMINALS EXCEPT KPBI. ADDITIONAL SHOWERS ARE SEEN JUST WEST OF THE EAST COAST SITES AND MAY BRIEFLY AFFECT THE TERMINALS BUT SHOULD REMAIN ISOLATED. WINDS SHOULD BE LIGHT AND VARIABLE OVERNIGHT BEFORE BECOMING NORTHWESTERLY DURING THE LATE MORNING HOURS TOMORROW. GUIDANCE IS HINTING AT AN EAST COAST SEA BREEZE DEVELOPING AND PUSHING INTO THE TERMINALS SO PREVAILED A GENERAL EASTERLY WIND AT ALL EAST COAST SITES EXCEPT KTMB WHICH MAY BE JUST TOO FAR INLAND TO SEE AN EASTERLY WIND. PREV DISCUSSION... /ISSUED 349 PM EDT WED OCT 1 2014/ SHORT TERM...(TONIGHT-FRIDAY NIGHT) THE LATEST SHORT-RANGE MODEL GUIDANCE REMAINS IN DECENT AGREEMENT AND INDICATES THE MOIST WESTERLY FLOW ACROSS THE AREA SOUTH A STALLED FRONTAL BOUNDARY CONTINUING THROUGH THE MAJORITY OF THE PERIOD. WESTERLY LOW-LEVEL FLOW UP TO 10 KFT COMBINED WITH THE EAST COAST SEA BREEZE WILL FOCUS THE BULK OF THIS ACTIVITY ACROSS THE CENTRAL AND EASTERN PORTIONS OF THE AREA EACH DAY...ESPECIALLY AS THE DEEP WESTERLY FLOW WEAKENS. MODEL PWAT GRADIENTS REFLECT THIS POTENTIAL AND INDICATE VALUES RANGING FROM 1.62" ALONG THE GULF COAST UP TO AROUND 2" ALONG THE EAST COAST THROUGH THE AFTERNOON/EVENING PERIODS THURSDAY AND FRIDAY. ALTHOUGH THE SEVERE THUNDERSTORM THREAT WILL REMAIN LOW THROUGH THIS TIME...PERIODS OF HEAVY RAINFALL COULD RESULT IN LOCALIZED FLOODING ACROSS THE EAST COAST AREAS. /AG LONG TERM (SATURDAY-WEDNESDAY)... A SIGNIFICANT CHANGE IN THE WEATHER IS LOOKING MORE LIKELY FOR THE LATER PART OF THE WEEKEND AS NOW BOTH GFS AND ECMWF ARE SENDING THE FIRST COLD FRONT OF THIS FALL SEASON ACROSS SOUTH FL SATURDAY NIGHT AND OFF OUR COAST SUNDAY MORNING. GFS ENSEMBLES ARE SUPPORTING THIS FROPA IDEA AS WELL...WITH THE AVERAGE OF THE MEMBERS A DEGREE OR TWO BELOW THE OPERATIONAL GFS MOS SUNDAY AND SUNDAY NIGHT. GIVEN THIS...HAVE TRENDED THE FORECAST COOLER SUNDAY THROUGH TUESDAY. THIS WOULD BE A VERY NOTICEABLE CHANGE FROM THE SULTRY HIGH DEWPOINTS WE`VE FELT SINCE MAY...WELL INTO THE 70S. BEHIND THE FRONT, DEWPOINTS WILL FALL INTO THE 60S ON A NICE NORTHERLY BREEZE. HIGHS ON SUNDAY ARE FORECAST TO BE ONLY IN THE LOWER-MID 80S. LOWS ARE FORECAST TO DROP INTO THE 60S INTERIOR AND GULF COAST BOTH SAT AND SUN NIGHT...AND LOWER 70S EAST COAST METRO WITH COMFORTABLE HUMIDITY...LETTING US KNOW THAT IT IS INDEED FALL. THIS IS PRETTY EARLY IN THE SEASON FOR A COLD FRONT, BUT THE PATTERN OF AN AMPLIFIED TROUGH ACROSS THE EASTERN CONUS DOES NOT SEEM TO WANT TO LET GO AS THE TROUGH CONTINUES RE-ESTABLISHING ITSELF EVEN AFTER TEMPORARY FLOW CHANGES. GIVEN THIS, AN EARLY SEASON COLD FRONT ISN`T SHOCKING...AND IN FACT THE LONGER RANGE GFS SHOWS ANOTHER COLD FRONT AS WE ENTER MID OCTOBER. COULD THIS BE THE BEGINNING OF A PARADE OF COLD FRONTS? TOO EARLY TO SAY, BUT I`M INCLINED TO BELIEVE SO GIVEN THE AFOREMENTIONED LOCKED SYNOPTIC PATTERN. /GREGORIA MARINE... A FRONTAL BOUNDARY WILL STALL ACROSS THE STATE THROUGH FRIDAY WITH LIGHT WINDS AND LOW SEAS CONTINUING. THE FIRST STRONG COLD FRONT OF THE FALL SEASON IS FORECAST TO SWEEP ACROSS THE LOCAL WATERS SATURDAY NIGHT WITH HIGH PRESSURE BUILDING FROM THE NORTH IN ITS WAKE ON SUNDAY. SEAS WILL INCREASE BEHIND THE COLD FRONT FROM THE NORTH, ESPECIALLY OFF THE PALM BEACH COAST. /AG && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 76 86 76 86 / 20 50 10 50 FORT LAUDERDALE 77 87 76 87 / 20 50 10 50 MIAMI 76 87 75 87 / 20 50 10 50 NAPLES 76 86 76 85 / 0 30 10 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
300 AM MDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH SATURDAY NIGHT) ISSUED AT 300 AM MDT THU OCT 2 2014 TODAY-TONIGHT...UPPER TROUGH THAT BROUGHT SHOWERS AND THUNDERSTORMS TO THE AREA LAST NIGHT AND EARLY THIS MORNING WILL EXIT THE AREA BY NOON TIME LEAVING A GENERALLY CLEAR SKY. THIS WILL BE SHORT LIVED AS ANOTHER UPPER TROUGH AND ASSOCIATED COLD FRONT BLOW THROUGH THE FORECAST AREA AROUND OR SHORTLY AFTER MIDNIGHT. MAIN IMPACT WITH THIS WILL BE AN INCREASE IN CLOUDINESS AND A ONE TO THREE HOUR PERIOD OF STRONG NORTH TO NORTHWEST WINDS. CENTER OF 12MB 3 HOURLY PRESSURE RISE COUPLET ENTERS YUMA COUNTY AROUND 07Z STEADILY MOVING SOUTHEAST TOWARD THE INTERSTATE BY 09Z THEN SLOWLY WEAKENING AS IT EXITS THE AREA BY 12Z. WILL NEED TO MONITOR FOR POSSIBILITY OF A WIND ADVISORY. BEHIND THE COLD FRONT IS AN AREA OF LOW AND MID LEVEL MOISTURE WITH SOME ELEVATED CAPE AND MODESTLY LOW INHIBITION. THIS AREA OF INSTABILITY IS NEAR THE LEFT FRONT QUAD OF APPROACHING 130+KT 250 JET. FELT THAT A THUNDERSTORM CANT BE RULED OUT AROUND 09Z FOR AREAS FROM TRENTON TO HILL CITY AND POINTS EAST. HIGH TEMPERATURES IN THE 60S. LOW TEMPERATURES IN THE LOW TO MID 30S IN FAR EASTERN COLORADO WITH MID 30S TO AROUND 40 EAST OF THE CO/KS BORDER. FROST AND POSSIBLY A FREEZE FOR PARTS OF FAR EASTERN COLORADO WEST OF A LINE FROM YUMA TO STRATTON TO NEAR WILD HORSE. WILL LET DAYSHIFT TAKE A LOOK AT 12Z DATA BEFORE DECIDING ON POSSIBLE HEADLINES. FRIDAY-FRIDAY NIGHT...BREEZY TO WINDY NORTHWEST WINDS EXPECTED DURING THE MORNING WITH A SLOW DECREASE FROM WEST TO EAST DURING THE AFTERNOON AS PRESSURE GRADIENT RELAXES. GENERALLY SUNNY CONDITIONS WITH AN INCREASE IN MID AND HIGH CLOUDS LATE FRIDAY NIGHT FROM THE NORTH. HIGH TEMPERATURES IN THE MID 50S TO AROUND 60. LOW TEMPERATURES IN THE LOW TO MID 30S. FROST POSSIBLE FOR THE KIT CARSON TO AROYA COLORADO AREA AND EAST OF A LINE FROM NEAR WRAY COLORADO TO NEAR GEM AND HILL CITY KANSAS. FREEZE POSSIBLE IN RED WILLOW COUNTY. HILITES POSSIBLY NEEDED. RECORD LOW TEMPERATURE POSSIBLE AT MCCOOK (SEE CLIMATE SECTION BELOW). HAVE ADDED RECORD/NEAR RECORD WORDING TO THE ZFPGLD. SATURDAY-SATURDAY NIGHT...MID AND HIGH CLOUDINESS CONTINUE ACROSS THE AREA UNDER NORTHWEST FLOW ALOFT. WARMER TEMPERATURES EXPECTED WITH DAYTIME HIGHS 70 TO 75 AND OVERNIGHT LOWS IN THE LOW TO MID 40S. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 219 AM MDT THU OCT 2 2014 THE LONG TERM FORECAST WILL CONTINUE TO BE DIRECTLY AFFECTED BY A MERIDIONAL FLOW PATTERN ACROSS THE CONUS...WITH A LARGE CUTOFF LOW OVER UPPER ONTARIO AND A RIDGE BUILDING IN THE WESTERN THIRD OF THE CONUS. STRONG NORTHWEST FLOW ALOFT WILL BRING STABLE CONDITIONS TO THE AREA THROUGH THE LONG TERM FORECAST PERIOD. A DRY COLD FRONT WILL PASS THROUGH THE HIGH PLAINS SUNDAY MORNING...BRINGING COOLER BUT NEAR NORMAL TEMPERATURES TO THE TRI STATE AREA. EXPECTING HIGH TEMPERATURES TO RANGE FROM THE LOWER TO MID 70S. TEMPERATURES WILL BEGIN TO REBOUND INTO THE UPPER 70S TO LOWER 80S TOWARDS THE MIDDLE OF NEXT WEEK...WHICH IS ABOUT 5 TO 10 DEGREES ABOVE AVERAGE FOR OCTOBER. LOW TEMPERATURES FOR THE PERIOD WILL FALL BETWEEN THE UPPER 40S TO LOWER 50S...WHICH IS ALSO BETWEEN 5 AND 10 DEGREES ABOVE NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1105 PM MDT WED OCT 1 2014 VFR CONDITIONS SHOULD DETERIORATE TO MVFR OVERNIGHT AT KGLD AND KMCK AS NORTHWEST WIND DECREASES AND TEMPERATURES COOL TO THE DEWPOINT. FORECAST SOUNDINGS AND THE HRRR INDICATE THAT STRATUS SHOULD DISSIPATE BY MID TO LATE MORNING AS WINDS INCREASE WITH VFR CONDITIONS FOR THE REMAINDER OF THIS FORECAST. && .CLIMATE... ISSUED AT 300 AM MDT THU OCT 2 2014 RECORD LOW TEMPERATURE POSSIBLE SATURDAY MORNING OCTOBER 4TH AT MCCOOK NEBRASKA. CURRENT RECORD LOW FOR THE DATE IS 32 DEGREES SET BACK IN 1911. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...99 LONG TERM...MK AVIATION...FS CLIMATE...99
AREA FORECAST DISCUSSION
NWS GOODLAND KS
219 AM MDT THU OCT 2 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 114 PM MDT WED OCT 1 2014 18Z WATER VAPOR IMAGERY/RAP ANALYSIS INDICATED STRONG TROUGH MOVING INTO NORTHERN COLORADO. AT THE SFC...FAIRLY DRY AIRMASS IN PLACE ACROSS THE TRI STATE AREA WITH FRONT DRAPED FROM KLBL TO KMCI. MAIN FORECAST CONCERN FOR THE PERIOD WILL CENTER AROUND APPROACHING SHORT WAVE TROUGH AND DEVELOPMENT OF PRECIPITATION AS IT MOVES INTO THE AREA. WHILE SEEING CURRENT DRY AIR IN THE AREA DOES CAUSE SOME CONCERN ON PRECIP DEVELOPMENT...BULK OF NEAR TERM MODELS ALL INDICATE A TAP OF MOISTURE ORIGINATING NEAR SFC FRONT AND INTERACTING WITH ELEVATED FRONTAL ZONE THIS EVENING. MIXING RATIOS IN THIS PLUME ARE HIGH AND WITH SOME ELEVATED INSTABILITY EXPECT A DECENT RESPONSE TO PERIOD OF STRONG FRONTOGENESIS. SOMEWHAT SURPRISED BY CONSISTENCY OF QPF OUTPUT FROM AVAILABLE DATA SOURCES AND AM COMFORTABLE INCREASING GENERAL AMOUNTS TO 0.25 TO 0.75 AT MOST LOCATIONS. CHOSE NOT TO GO ON THE HIGH END OF PRECIPITATION THOUGH...DUE TO AFOREMENTIONED CONCERNS OVER MOISTURE QUALITY. FORCING WILL DIMINISH TOWARDS SUNRISE AS DEEP CAA TAKES OVER. SURPRISINGLY...SOME LOW TOPPED INSTABILITY DOES EXIST THROUGH THE MORNING HOURS SO A FEW LINGERING SHOWERS APPEAR WARRANTED. OTHER CONCERN FOR THE NEAR TERM WILL BE WINDS BEHIND STRONG COLD FRONT ADVANCING ACROSS THE AREA TONIGHT. 12Z NAM AND TO A LESSER DEGREE THE RAP INDICATE STRONG 3 HR PRESSURE RISES IN EXCESS OF 6MB AS FRONT PASSES. THIS COULD LEAD TO A PERIOD OF NEAR ADVISORY LEVEL GUSTS FOR AN HOUR OR TWO BEHIND THE FRONT. PLAYED UP WINDS A BIT IN THE FORECAST...BUT UNTIL STRONG PRESSURE RISES/GUSTS BECOME MORE APPARENT IN OBSERVATIONAL DATA PLAN ON HOLDING OFF ON ANY HIGHLIGHTS. .LONG TERM...(SUNDAY THROUGH WEDNESDAY) ISSUED AT 219 AM MDT THU OCT 2 2014 THE LONG TERM FORECAST WILL CONTINUE TO BE DIRECTLY AFFECTED BY A MERIDIONAL FLOW PATTERN ACROSS THE CONUS...WITH A LARGE CUTOFF LOW OVER UPPER ONTARIO AND A RIDGE BUILDING IN THE WESTERN THIRD OF THE CONUS. STRONG NORTHWEST FLOW ALOFT WILL BRING STABLE CONDITIONS TO THE AREA THROUGH THE LONG TERM FORECAST PERIOD. A DRY COLD FRONT WILL PASS THROUGH THE HIGH PLAINS SUNDAY MORNING...BRINGING COOLER BUT NEAR NORMAL TEMPERATURES TO THE TRI STATE AREA. EXPECTING HIGH TEMPERATURES TO RANGE FROM THE LOWER TO MID 70S. TEMPERATURES WILL BEGIN TO REBOUND INTO THE UPPER 70S TO LOWER 80S TOWARDS THE MIDDLE OF NEXT WEEK...WHICH IS ABOUT 5 TO 10 DEGREES ABOVE AVERAGE FOR OCTOBER. LOW TEMPERATURES FOR THE PERIOD WILL FALL BETWEEN THE UPPER 40S TO LOWER 50S...WHICH IS ALSO BETWEEN 5 AND 10 DEGREES ABOVE NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1105 PM MDT WED OCT 1 2014 VFR CONDITIONS SHOULD DETERIORATE TO MVFR OVERNIGHT AT KGLD AND KMCK AS NORTHWEST WIND DECREASES AND TEMPERATURES COOL TO THE DEWPOINT. FORECAST SOUNDINGS AND THE HRRR INDICATE THAT STRATUS SHOULD DISSIPATE BY MID TO LATE MORNING AS WINDS INCREASE WITH VFR CONDITIONS FOR THE REMAINDER OF THIS FORECAST. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JRM LONG TERM...MK AVIATION...FS
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1117 PM MDT WED OCT 1 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 114 PM MDT WED OCT 1 2014 18Z WATER VAPOR IMAGERY/RAP ANALYSIS INDICATED STRONG TROUGH MOVING INTO NORTHERN COLORADO. AT THE SFC...FAIRLY DRY AIRMASS IN PLACE ACROSS THE TRI STATE AREA WITH FRONT DRAPED FROM KLBL TO KMCI. MAIN FORECAST CONCERN FOR THE PERIOD WILL CENTER AROUND APPROACHING SHORT WAVE TROUGH AND DEVELOPMENT OF PRECIPITATION AS IT MOVES INTO THE AREA. WHILE SEEING CURRENT DRY AIR IN THE AREA DOES CAUSE SOME CONCERN ON PRECIP DEVELOPMENT...BULK OF NEAR TERM MODELS ALL INDICATE A TAP OF MOISTURE ORIGINATING NEAR SFC FRONT AND INTERACTING WITH ELEVATED FRONTAL ZONE THIS EVENING. MIXING RATIOS IN THIS PLUME ARE HIGH AND WITH SOME ELEVATED INSTABILITY EXPECT A DECENT RESPONSE TO PERIOD OF STRONG FRONTOGENESIS. SOMEWHAT SURPRISED BY CONSISTENCY OF QPF OUTPUT FROM AVAILABLE DATA SOURCES AND AM COMFORTABLE INCREASING GENERAL AMOUNTS TO 0.25 TO 0.75 AT MOST LOCATIONS. CHOSE NOT TO GO ON THE HIGH END OF PRECIPITATION THOUGH...DUE TO AFOREMENTIONED CONCERNS OVER MOISTURE QUALITY. FORCING WILL DIMINISH TOWARDS SUNRISE AS DEEP CAA TAKES OVER. SURPRISINGLY...SOME LOW TOPPED INSTABILITY DOES EXIST THROUGH THE MORNING HOURS SO A FEW LINGERING SHOWERS APPEAR WARRANTED. OTHER CONCERN FOR THE NEAR TERM WILL BE WINDS BEHIND STRONG COLD FRONT ADVANCING ACROSS THE AREA TONIGHT. 12Z NAM AND TO A LESSER DEGREE THE RAP INDICATE STRONG 3 HR PRESSURE RISES IN EXCESS OF 6MB AS FRONT PASSES. THIS COULD LEAD TO A PERIOD OF NEAR ADVISORY LEVEL GUSTS FOR AN HOUR OR TWO BEHIND THE FRONT. PLAYED UP WINDS A BIT IN THE FORECAST...BUT UNTIL STRONG PRESSURE RISES/GUSTS BECOME MORE APPARENT IN OBSERVATIONAL DATA PLAN ON HOLDING OFF ON ANY HIGHLIGHTS. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 149 PM MDT WED OCT 1 2014 THURSDAY NIGHT-FRIDAY NIGHT... A SECOND COLD FRONT WILL MOVE ACROSS THE REGION LATE THURSDAY NIGHT ALONG WITH FRONT END OF H3 JET ON BACK SIDE OF UPPER LEVEL TROUGH. WITH STRONG FRONTOGENETICAL AND UPPER LEVEL FORCING I DECIDED TO KEEP 20 POPS ACROSS NW PART OF CWA THURSDAY NIGHT DESPITE LIMITED MOISTURE PROFILES. STRONG PRESSURE RISES BEHIND THE FRONT SHOULD ALLOW A BRIEF PERIOD OF NEAR ADVISORY OR ADVISORY WINDS (45 MPH) AS PRESSURE GRADIENT TIGHTENS OVERNIGHT. NAM IN PARTICULAR SHOWS 6HR PRESSURE RISES IN EXCESS OF 10MB WHICH IS CONCERNING AND COULD INDICATE POSSIBILITY OF BRIEF WARNING CRITERIA WINDS. IF THERE IS VIRGA OR LIGHT SHOWERS THIS MAY ALSO HELP MIX STRONGER WINDS TO THE SURFACE. WILL HOLD OFF FOR NOW ON HEADLIGHTS...BUT THIS NEEDS TO BE MONITORED. GRADIENT RELAXES FROM THE WEST TO THE EAST AS UPPER LEVEL JET AND TROUGH AXIS MOVE EAST...HOWEVER THERE ARE STILL STRONG WINDS ALOFT OVER THE EASTERN CWA THROUGH THE DAY FRIDAY. PROFILES WOULD LIMIT MIXING TO BELOW WHERE STRONGEST WINDS ALOFT ARE FRIDAY DESPITE SUNNY CONDITIONS...SO ADVISORY LEVEL WINDS SEEM UNLIKELY DURING THE DAY FRIDAY. SHOULD STILL BE WINDY...ESPECIALLY FRIDAY AFTERNOON. VERY COOL AIR MASS SETTLES INTO REGION THURSDAY NIGHT AND FRIDAY. IF IT WASNT FOR INCREASING CLOUD COVER AND WINDY CONDITIONS THIS AIR MASS WOULD HAVE SUPPORTED A HARD FREEZE (LOOKS LIKE WELL LUCK OUT). CLEAR SKIES...LOW TD...AND LIGHT WINDS WILL SUPPORT GOOD RADIATIONAL CONDITIONS FRIDAY NIGHT. AT THE SAME TIME TEMPS ALOFT WILL BE MODERATING AS A RIDGE OVER THE SW US BEGINS TO BUILD EAST. MOST OF THE CWA SHOULD STAY ABOVE FREEZING...THOUGH PATCHY FROST WILL CERTAINLY BE POSSIBLE IN THE NORTH AND NORTHEAST WHERE OVERNIGHT LOWS IN THE 33-35F RANGE ARE EXPECTED. SATURDAY-WEDNESDAY... GUIDANCE IN DECENT AGREEMENT ON RIDGE BUILDING ACROSS WESTERN US WITH MAIN UPPER LEVEL JET STREAM SHIFTING WELL NORTH AND EAST OF CWA. ECMWF IS SHOWING A WEAK SHORTWAVE TROUGH ROTATING AROUND CLOSE UPPER LOW OVER GREAT LAKES POSSIBLY BRINGING SHOWERS/THUNDERSTORMS BACK TO NORTHERN PLAINS...POSSIBLY AS FAR WEST AS OUR CWA. THERE ISNT A LOT OF CONSISTENCY ON THIS WEAK FEATURE BETWEEN DETERMINISTIC AND ENSEMBLES SO I KEPT SUN/SUN NIGHT DRY. TEMPERATURES WILL MODERATE THROUGH THESE PERIODS WITH HIGH TEMPS IN THE UPPER 70S LOWER 80S BY EARLY NEXT WEEK AND PERSISTENT DRY CONDITIONS. CONSENSUS/MODEL BLEND SEEMED APPROPRIATE...SO LITTLE CHANGE FROM PREVIOUS FORECAST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1105 PM MDT WED OCT 1 2014 VFR CONDITIONS SHOULD DETERIORATE TO MVFR OVERNIGHT AT KGLD AND KMCK AS NORTHWEST WIND DECREASES AND TEMPERATURES COOL TO THE DEWPOINT. FORECAST SOUNDINGS AND THE HRRR INDICATE THAT STRATUS SHOULD DISSIPATE BY MID TO LATE MORNING AS WINDS INCREASE WITH VFR CONDITIONS FOR THE REMAINDER OF THIS FORECAST. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...JRM LONG TERM...DR AVIATION...FS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
110 AM CDT THU OCT 2 2014 .UPDATE... ISSUED AT 1049 PM CDT WED OCT 1 2014 ISSUED A DENSE FOG ADVY FOR THE ERN HALF OF OUR MN AND MOST OF OUR WI CWA. COLD FRONT IS MAKING LITTLE IF ANY PROGRESS EAST AND AT 11 PM WAS ONLY TO A REDWOOD FALLS TO LONG PRAIRIE LINE...WITH WIDESPREAD IFR/LIFR STRATUS ALREADY IN PLACE. WITH LIGHT WINDS AND MOIST BOUNDARY LAYER FROM RAINS YESTERDAY...EXPECT THIS STRATUS TO DESCEND TO THE GROUND AND BECOME DENSE FOG TONIGHT. INITIAL AREA ISSUED FOR WAS BASED ON WHERE THE HRRR SHOWS DENSE FOG FORMING...ALONG WITH WHERE THE 21Z HOPWRF SHOWS 75% OR GREATER PROBABILITIES FOR VISIBILITIES LESS THAN A HALF MILE. WILL WATCH VISIBILITY TRENDS THE NEXT COUPLE OF HOURS...BUT THINKING WE WILL PROBABLY HAVE TO FILL IN RUSK/CHIP/EAU CLAIRE COUNTIES AS WELL. IF FRONT DOES NOT MAKE MUCH MORE PROGRESS EAST IN THE NEXT COUPLE OF HOURS...MAY HAVE TO ADD A ROW OR TWO OF COUNTIES ON THE WEST END AS WELL...BUT FOR NOW...AREA WITH HIGHEST CONFIDENCE FOR SEEING DENSE FOG IS HIGHLIGHTED IN THE ADVY. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 316 PM CDT WED OCT 1 2014 AFTERNOON ANALYSIS SHOWS A STACKED LOW OVER MANITOBA...WITH THE ASSOCIATED BOUNDARY STRADDLING THE MN/DAKOTAS BORDER. THE FIRST RELATED WAVE OF LIFT GENERATED A HEALTHY AREA OF SHOWERS THAT WILL CONTINUE TO LIFT FROM EAST CENTRAL MN AND WEST CENTRAL WI TOWARD LAKE SUPERIOR. IN ITS WAKE...RESIDUAL LOW LEVEL MOISTURE AND LIGHT WINDS WILL CONTRIBUTE TO PESKY STRATUS AND FOG DEVELOPMENT TONIGHT INTO THURSDAY. WILL NEED TO WATCH WEST CENTRAL WISCONSIN WHERE CONDITIONS COULD LEAD TO DENSE FOG OVERNIGHT...PARTICULARLY NEAR EAU CLAIRE. ON THURSDAY...THE NEXT WAVE EJECTS NORTHEAST ACROSS THE AREA FROM THE SOUTHERN STREAM SYSTEM. EXPECT ANOTHER ROUND OF RAIN WITH A FEW THUNDERSTORMS TO BLOSSOM OVER SOUTH/EAST CENTRAL MN AND WEST CENTRAL WI THURSDAY AFTERNOON. THE PRIMARY UNCERTAINTY IS HOW FAR WEST THE PRECIPITATION SHIELD WILL EXTEND. HAVE LEANED TOWARD THE NAM/ECMWF WHICH RESTRICT THE CATEGORICAL POPS EAST OF A REDWOOD FALLS TO ST CLOUD MN LINE. HAVE INCLUDED 70-80 POPS ALONG AND EAST OF THE INTERSTATE 35 CORRIDOR FOR THURSDAY AFTERNOON. TEMPERATURES TONIGHT WILL HANG IN THE UPPER 40S TO MID 50S UNDER THE EXTENSIVE CLOUD COVER...WITH LOW/MID 60S ANTICIPATED FOR THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 316 PM CDT WED OCT 1 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE LONG TERM FORECAST PICKS UP DURING QUITE AN ACTIVE PERIOD OF WEATHER. AN IMPRESSIVE FALL LOW PRESSURE SYSTEM WILL BE COMING TOGETHER ACROSS THE MIDWEST BY THURSDAY EVENING...AND WILL SPREAD MODERATE TO HEAVY RAIN AT TIMES INTO SOUTHEASTERN MINNESOTA THROUGH WESTERN WISCONSIN. AT THIS TIME...AN UPPER LEVEL TROUGH THAT IS POSITIONED OVER THE FOUR CORNERS REGION TODAY...WILL LIFT NORTHEAST AS IT BEGINS TO PHASE WITH A DEEPLY AMPLIFIED NORTHERN TROUGH DROPPING SOUTHEAST FROM ALBERTA THROUGH SASKATCHEWAN. STRONG FRONTOGENESIS...ACCOMPANIED BY DECENT DIFFERENTIAL DIVERGENCE AND STRONG ISENTROPIC LIFT WILL BE FOCUSED FROM A LINE NEAR FAIRMONT...THROUGH THE EAST METRO TOWARD TAYLORS FALLS AND AREAS TO THE EAST. THE SURFACE LOW WILL ADVANCE NORTHEAST FROM MISSOURI TO NEAR GREEN BAY BY MIDNIGHT THURSDAY NIGHT...AND WILL RAPIDLY DEEPEN OVERNIGHT THROUGH MUCH OF FRIDAY AS THE NORTHERN AND SOUTHERN TROUGHS PHASE TOGETHER. FOR MUCH OF CENTRAL AND ESPECIALLY WESTERN MINNESOTA...FRIDAY WILL BE MOSTLY DRY. HOWEVER...THE DEEPENING SURFACE LOW WILL CREATE VERY WINDY CONDITIONS AS A 1030MB SURFACE HIGH MOVE IN TO MONTANA...MEANING QUITE A TIGHT PRESSURE GRADIENT IS EXPECTED ACROSS THE UPPER MIDWEST THROUGH THE DAY. THE CENTER OF THE UPPER TROUGH WILL BE OVERHEAD BY MID DAY...AND STRONG COLD AIR ADVECTION WILL HOLD DAYTIME TEMPERATURES ABOUT 20 DEGREES BELOW SEASONAL NORMALS. COLD AIR ADVECTION LOOKS STRONGER AT THIS POINT WITH 850H TEMPS OF -4 TO -6...SO COOLED HIGH TEMPS FRIDAY BY ABOUT TWO TO THREE DEGREES EVERYWHERE...MEANING MOST WILL SEE HIGHS IN THE 40S...WITH WIND CHILL VALUES LOWER THAN THAT. ON FRIDAY NIGHT...MODELS INDICATE AN AREA OF DECENT THETA-E ADVECTION MOVING THROUGH ON THE BACKSIDE OF THE SYSTEM WHICH MAY PRODUCE LIGHT PRECIP ACROSS THE EASTERN HALF OF THE CWA. TEMPERATURES LOOK TO BE COLD ENOUGH FOR MIXING IN SOME SNOWFLAKES OVERNIGHT...ESPECIALLY ACROSS WESTERN WISCONSIN...BUT AT THIS TIME NO ACCUMULATION IS EXPECTED. SATURDAY THROUGH MONDAY...DURING THIS PERIOD...THE AFOREMENTIONED FALL SYSTEM WILL ADVANCE NORTH TOWARD HUDSON BAY AND CONTINUE DEEPENING INITIALLY. MAINLY DRY CONDITIONS ARE IN THE FORECAST FOR OUR AREA. THE UPPER TROUGH WILL KEEP THE STRONG NORTHWEST WIND FLOWING OVER OUR AREA DURING THIS TIME...MEANING QUITE A COLD WEEKEND IS IN STORE. EARLY SATURDAY MORNING...TEMPERATURES IN THE 30S WILL BE COMMON...WITH AREAS IN THE NORTHWEST POTENTIALLY DROPPING BELOW FREEZING. FROM SUNDAY THROUGH MONDAY...THE STRONG SYSTEM WILL RETROGRADE TO JUST SOUTHWEST OF THE HUDSON BAY AND BECOME VERTICALLY STACKED. MONDAY NIGHT THROUGH WEDNESDAY...THE WEAKENING SYSTEM WILL BEGIN PUSHING EAST AND 850H TEMPS WILL BE ON THE RISE. TEMPERATURES ARE EXPECTED TO RETURN TO THE 60S FOR HIGHS ON TUESDAY. DISAGREEMENT REMAINS BETWEEN THE GFS/EC ABOUT THE UPPER PATTERN TOWARD THE MIDDLE AND END OF NEXT WEEK...WHICH WILL DICTATE TEMPERATURES ACROSS THE MIDWEST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1254 AM CDT THU OCT 2 2014 TWO CONCERNS THE TAF PERIOD ARE THE DENSE FOG IN THE PROCESS OF FORMING AND THE TIMING OF RAIN LATE THIS MORNING INTO THE AFTERNOON. AT 6Z...THE FRONT IS ONLY TO ABOUT A RWF TO LONG PRAIRIE LINE. EAST OF THE FRONT IT IS UGLY...WITH LIFR CIGS QUICKLY BECOMING 1/4SM OR LESS FG. AXN WILL REMAIN WEST OF THE FOG...AM HOPING THE FRONT WILL WORK THROUGH RWF ENOUGH TO KEEP THEM OUT OF THE FOG...BUT WILL BE CLOSE. FOR STC/MSP/RNH/EAU... CONFIDENCE IS HIGH THAT DENSE FOG WILL BE A SIGNIFICANT ISSUE THROUGH 15Z. ONLY QUESTION REALLY IS WHEN DOES IT HAPPEN. HAVE IT HAPPENING AT MSP THE LATEST. AREA OF RAIN CURRENTLY IN CENTRAL NEB WILL BE HEADING THIS WAY THIS MORNING. STUCK CLOSE TO A GFS/HRRR/RAP/HOPWRF BLEND FOR BRINGING RAIN ACROSS ALL MN TERMINALS THIS MORNING AND WI TERMINALS THIS AFTERNOON. WINDS WILL REMAIN FAIRLY LIGHT THROUGH TODAY...BUT THU EVENING...WE WILL FINALLY START TO GET SOME PRESSURE RISES INTO WRN MN...MARKING THE BEGINNING OF WHAT WILL BE A BREEZY THU NIGHT AND FRIDAY. KMSP...HAVE HIGH CONFIDENCE IN DENSE FOG SIGNIFICANTLY IMPACTING THE MORNING PUSH THIS MORNING AT MSP. GIVEN HOW WIDESPREAD THE DENSE FOG IS AROUND THE CITIES AT 6Z...MSP WILL NOT BE ESCAPING THE FOG. THE MAIN QUESTION IS HOW LOW TO GO WITH VSBYS...BUT CURRENT TAF MAY NOT BE LOW ENOUGH. THERE IS A HIGH CHANCE THAT VISIBILITIES THIS MORNING WILL DROP BELOW AIRPORT MINIMUMS...WITH SIGNIFICANT IMPACTS TO AIRPORT ARRIVAL RATES LIKELY BETWEEN 10Z AND 14Z. AFTER THAT...STUCK CLOSE TO WHAT THE PREVIOUS TAF HAD FOR THE TIMING OF RAIN INTO THE FIELD...AND LOOKS LIKE WE WILL SEE ANOTHER SEVERAL HOUR ROUND OF RAIN THIS AFTERNOON...MUCH LIKE WE SAW YESTERDAY. BY THE END OF THE TAF...MSP WILL START FEELING THE STRONGER WINDS...BUT THE MORE SIGNIFICANT NW WINDS AND GUSTS WILL NOT NEED TO SHOW UP UNTIL THE LAST 6 HOURS OF THE 12Z TAF PACKAGE. /OUTLOOK FOR KMSP/ FRI...MAINLY MVFR WITH CHC -SHRA. WINDS WNW 20G30 KTS. SAT...VFR. WINDS NW 10-15 KTS. SUN...VFR. WINDS NW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ043>045- 050>053-059>063-066>070-074>078-082>085-091>093. WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR WIZ014-015- 023>026. && $$ UPDATE...MPG SHORT TERM...LS LONG TERM...SPD AVIATION...MPG
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1113 PM CDT WED OCT 1 2014 .UPDATE... ISSUED AT 1049 PM CDT WED OCT 1 2014 ISSUED A DENSE FOG ADVY FOR THE ERN HALF OF OUR MN AND MOST OF OUR WI CWA. COLD FRONT IS MAKING LITTLE IF ANY PROGRESS EAST AND AT 11 PM WAS ONLY TO A REDWOOD FALLS TO LONG PRAIRIE LINE...WITH WIDESPREAD IFR/LIFR STRATUS ALREADY IN PLACE. WITH LIGHT WINDS AND MOIST BOUNDARY LAYER FROM RAINS YESTERDAY...EXPECT THIS STRATUS TO DESCEND TO THE GROUND AND BECOME DENSE FOG TONIGHT. INITIAL AREA ISSUED FOR WAS BASED ON WHERE THE HRRR SHOWS DENSE FOG FORMING...ALONG WITH WHERE THE 21Z HOPWRF SHOWS 75% OR GREATER PROBABILITIES FOR VISIBILITIES LESS THAN A HALF MILE. WILL WATCH VISIBILITY TRENDS THE NEXT COUPLE OF HOURS...BUT THINKING WE WILL PROBABLY HAVE TO FILL IN RUSK/CHIP/EAU CLAIRE COUNTIES AS WELL. IF FRONT DOES NOT MAKE MUCH MORE PROGRESS EAST IN THE NEXT COUPLE OF HOURS...MAY HAVE TO ADD A ROW OR TWO OF COUNTIES ON THE WEST END AS WELL...BUT FOR NOW...AREA WITH HIGHEST CONFIDENCE FOR SEEING DENSE FOG IS HIGHLIGHTED IN THE ADVY. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 316 PM CDT WED OCT 1 2014 AFTERNOON ANALYSIS SHOWS A STACKED LOW OVER MANITOBA...WITH THE ASSOCIATED BOUNDARY STRADDLING THE MN/DAKOTAS BORDER. THE FIRST RELATED WAVE OF LIFT GENERATED A HEALTHY AREA OF SHOWERS THAT WILL CONTINUE TO LIFT FROM EAST CENTRAL MN AND WEST CENTRAL WI TOWARD LAKE SUPERIOR. IN ITS WAKE...RESIDUAL LOW LEVEL MOISTURE AND LIGHT WINDS WILL CONTRIBUTE TO PESKY STRATUS AND FOG DEVELOPMENT TONIGHT INTO THURSDAY. WILL NEED TO WATCH WEST CENTRAL WISCONSIN WHERE CONDITIONS COULD LEAD TO DENSE FOG OVERNIGHT...PARTICULARLY NEAR EAU CLAIRE. ON THURSDAY...THE NEXT WAVE EJECTS NORTHEAST ACROSS THE AREA FROM THE SOUTHERN STREAM SYSTEM. EXPECT ANOTHER ROUND OF RAIN WITH A FEW THUNDERSTORMS TO BLOSSOM OVER SOUTH/EAST CENTRAL MN AND WEST CENTRAL WI THURSDAY AFTERNOON. THE PRIMARY UNCERTAINTY IS HOW FAR WEST THE PRECIPITATION SHIELD WILL EXTEND. HAVE LEANED TOWARD THE NAM/ECMWF WHICH RESTRICT THE CATEGORICAL POPS EAST OF A REDWOOD FALLS TO ST CLOUD MN LINE. HAVE INCLUDED 70-80 POPS ALONG AND EAST OF THE INTERSTATE 35 CORRIDOR FOR THURSDAY AFTERNOON. TEMPERATURES TONIGHT WILL HANG IN THE UPPER 40S TO MID 50S UNDER THE EXTENSIVE CLOUD COVER...WITH LOW/MID 60S ANTICIPATED FOR THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 316 PM CDT WED OCT 1 2014 THURSDAY NIGHT THROUGH FRIDAY NIGHT...THE LONG TERM FORECAST PICKS UP DURING QUITE AN ACTIVE PERIOD OF WEATHER. AN IMPRESSIVE FALL LOW PRESSURE SYSTEM WILL BE COMING TOGETHER ACROSS THE MIDWEST BY THURSDAY EVENING...AND WILL SPREAD MODERATE TO HEAVY RAIN AT TIMES INTO SOUTHEASTERN MINNESOTA THROUGH WESTERN WISCONSIN. AT THIS TIME...AN UPPER LEVEL TROUGH THAT IS POSITIONED OVER THE FOUR CORNERS REGION TODAY...WILL LIFT NORTHEAST AS IT BEGINS TO PHASE WITH A DEEPLY AMPLIFIED NORTHERN TROUGH DROPPING SOUTHEAST FROM ALBERTA THROUGH SASKATCHEWAN. STRONG FRONTOGENESIS...ACCOMPANIED BY DECENT DIFFERENTIAL DIVERGENCE AND STRONG ISENTROPIC LIFT WILL BE FOCUSED FROM A LINE NEAR FAIRMONT...THROUGH THE EAST METRO TOWARD TAYLORS FALLS AND AREAS TO THE EAST. THE SURFACE LOW WILL ADVANCE NORTHEAST FROM MISSOURI TO NEAR GREEN BAY BY MIDNIGHT THURSDAY NIGHT...AND WILL RAPIDLY DEEPEN OVERNIGHT THROUGH MUCH OF FRIDAY AS THE NORTHERN AND SOUTHERN TROUGHS PHASE TOGETHER. FOR MUCH OF CENTRAL AND ESPECIALLY WESTERN MINNESOTA...FRIDAY WILL BE MOSTLY DRY. HOWEVER...THE DEEPENING SURFACE LOW WILL CREATE VERY WINDY CONDITIONS AS A 1030MB SURFACE HIGH MOVE IN TO MONTANA...MEANING QUITE A TIGHT PRESSURE GRADIENT IS EXPECTED ACROSS THE UPPER MIDWEST THROUGH THE DAY. THE CENTER OF THE UPPER TROUGH WILL BE OVERHEAD BY MID DAY...AND STRONG COLD AIR ADVECTION WILL HOLD DAYTIME TEMPERATURES ABOUT 20 DEGREES BELOW SEASONAL NORMALS. COLD AIR ADVECTION LOOKS STRONGER AT THIS POINT WITH 850H TEMPS OF -4 TO -6...SO COOLED HIGH TEMPS FRIDAY BY ABOUT TWO TO THREE DEGREES EVERYWHERE...MEANING MOST WILL SEE HIGHS IN THE 40S...WITH WIND CHILL VALUES LOWER THAN THAT. ON FRIDAY NIGHT...MODELS INDICATE AN AREA OF DECENT THETA-E ADVECTION MOVING THROUGH ON THE BACKSIDE OF THE SYSTEM WHICH MAY PRODUCE LIGHT PRECIP ACROSS THE EASTERN HALF OF THE CWA. TEMPERATURES LOOK TO BE COLD ENOUGH FOR MIXING IN SOME SNOWFLAKES OVERNIGHT...ESPECIALLY ACROSS WESTERN WISCONSIN...BUT AT THIS TIME NO ACCUMULATION IS EXPECTED. SATURDAY THROUGH MONDAY...DURING THIS PERIOD...THE AFOREMENTIONED FALL SYSTEM WILL ADVANCE NORTH TOWARD HUDSON BAY AND CONTINUE DEEPENING INITIALLY. MAINLY DRY CONDITIONS ARE IN THE FORECAST FOR OUR AREA. THE UPPER TROUGH WILL KEEP THE STRONG NORTHWEST WIND FLOWING OVER OUR AREA DURING THIS TIME...MEANING QUITE A COLD WEEKEND IS IN STORE. EARLY SATURDAY MORNING...TEMPERATURES IN THE 30S WILL BE COMMON...WITH AREAS IN THE NORTHWEST POTENTIALLY DROPPING BELOW FREEZING. FROM SUNDAY THROUGH MONDAY...THE STRONG SYSTEM WILL RETROGRADE TO JUST SOUTHWEST OF THE HUDSON BAY AND BECOME VERTICALLY STACKED. MONDAY NIGHT THROUGH WEDNESDAY...THE WEAKENING SYSTEM WILL BEGIN PUSHING EAST AND 850H TEMPS WILL BE ON THE RISE. TEMPERATURES ARE EXPECTED TO RETURN TO THE 60S FOR HIGHS ON TUESDAY. DISAGREEMENT REMAINS BETWEEN THE GFS/EC ABOUT THE UPPER PATTERN TOWARD THE MIDDLE AND END OF NEXT WEEK...WHICH WILL DICTATE TEMPERATURES ACROSS THE MIDWEST. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z THURSDAY EVENING) ISSUED AT 708 PM CDT WED OCT 1 2014 IFR OR LOWER CONDITIONS ARE IN PLACE AT TAF ISSUANCE TIME OVER MOST OF ERN MN AND WRN WI AS STRATUS AND VISIBILITIES LOWER. HOWEVER...VFR CONDITIONS ARE IN PLACE FROM JUST WEST OF ST CLOUD TO JUST WEST OF MANKATO. NOT ANTICIPATING THIS CLEARING TO MAKE MUCH OR ANY PROGRESS EASTWARD TONIGHT WITH CONDITIONS REMAINING STEADY OR SLOWLY DETERIORATING THROUGH THE OVERNIGHT. A SLOW IMPROVEMENT EXPECTED THURSDAY AHEAD OF MORE RAIN TO MOVE ACROSS ERN MN AND WRN WI LATE IN THE PERIOD. KMSP...IFR OR LIFR CONDITIONS THROUGH MID/LATE MORNING WITH MVFR RETURNING LATE IN THE PERIOD. /OUTLOOK FOR KMSP/ FRI...MAINLY MVFR WITH CHC -SHRA. WINDS WNW 20G30 KTS. SAT...VFR. WINDS NW 10-15 KTS. SUN...VFR. WINDS NW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...DENSE FOG ADVISORY FROM 2 AM TO 10 AM CDT THURSDAY FOR MNZ043>045-050>053-059>063-066>070-074>078-082>085-091>093. WI...DENSE FOG ADVISORY FROM 2 AM TO 10 AM CDT THURSDAY FOR WIZ014- 015-023>026. && $$ UPDATE...MPG SHORT TERM...LS LONG TERM...SPD AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
248 AM CDT Thu Oct 2 2014 ...Severe Weather and Heavy Rainfall Expected Across the Missouri Ozarks Today and This Evening... .SHORT TERM...(Today and Tonight) Issued at 222 AM CDT THU OCT 2 2014 There will be active weather during the morning commute for some across the Missouri Ozarks and southeast Kansas. Convection has been redeveloping across northeast Oklahoma and southeast Kansas moving slowly to the northeast. The HRRR has been handling this well and will see this convection continue mainly along and north of I-44 through mid morning. There will be a risk for stronger convection to develop this morning with large hail and damaging wind gusts the main threat along with frequent lightning and heavy rainfall. The short term models are in good agreement with the advancing cold front moving into southeast Kansas by mid afternoon. Initially discreet convection will develop along and just ahead of the front between 18-20z. This convection will quickly merge into a squall line or line segments as the line advances rather quickly eastward. Followed the HRRR closely for the afternoon convection. All modes of severe weather will be possible with damaging winds being the main threat...followed by large hail...and the risk of a couple isolated tornadoes. The line of storms will be near the Joplin area by 4 pm and Springfield area by 6 pm. The line will be clearing the eastern Missouri Ozarks before midnight this evening. Will leave the ongoing Flash Flood Watch as is with the heaviest storm total rainfall expected in the watch area where totals will be between 2 to 5 inches. Areas southeast of I-44 will see totals between 1 to 2 inches. .LONG TERM...(Friday through Wednesday) Issued at 222 AM CDT THU OCT 2 2014 Friday will be a blustery and much cooler day with passing clouds and perhaps some sprinkles or spotty light shower or two. The latest guidance shows a piece of upper level energy moving across the area especially the central Missouri area with some clouds and sprinkles possible. Winds will be gusty up to 25 mph and temperatures struggling to get above 60 degrees. Skies will clear Friday evening for Friday night football around the Missouri Ozarks but it will be chilly. The big question will be the frost potential. Guidance is a degree or two colder again with lows down in the middle to upper 30s likely. Wouldn`t be surprise a few colder spots that are protected get down in the lower 30s. Winds will possibly remain up around 5 mph or so. Will put back in the mention of patchy frost into the forecast especially valleys and wind protected areas. The frost potential will need to be looked at again over the next day for any possible headlines by Friday. People with sensitive outdoor plants will need to pay attention to the forecast for Friday night. Seasonably cool temperatures will stay around for the weekend and mostly dry conditions and a northwest flow. Guidance shows another weak mid level disturbance moving through on Monday with a few more clouds and possible light showers. The overall flow will flatten by the middle of next week with southerly winds returning. A moderation in temperatures will return with above normal temperatures by middle next week. && .AVIATION...(For the 06Z TAFS through 06Z Thursday Night) Issued at 1200 AM CDT THU OCT 2 2014 Convection should remain away from the terminals until closer to daybreak, with storms then affecting JLN, before moving east with time to impact SGF and BBG. Convection will initially be scattered in nature during the morning and early afternoon hours, before becoming better organized during the late afternoon and early evening as a strong cold front approaches. A line of strong, perhaps severe, thunderstorms will impact the region from west to east tomorrow afternoon or evening, though exact timing remains somewhat in question. IFR or lower is a good bet within stronger storms tomorrow, along with gusty winds. Have indicated most likely period for stronger storms with +TSRA mention, though again, timing is subject to change. That strong cold front will sweep across the region tomorrow evening, with a sharp wind shift to the northwest as it passes. MVFR cigs are then expected behind the front as much colder air builds in. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FLASH FLOOD WATCH through this evening FOR MOZ055>058-066>071- 077>081-088-089. KS...FLASH FLOOD WATCH through this evening FOR KSZ073-097-101. && $$ SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Boxell
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
1246 AM CDT Thu Oct 2 2014 .UPDATE: Issued at 1243 AM CDT Thu Oct 2 2014 Have expanded the Flash Flood Watch to include the remainder of northeast Missouri and west central Illinois (northwest of St. Louis Metro). Locations have received heavy rainfall tonight and expectation is that another few inches of rain overnight and later today could push some local streams, creeks, rivers out of their banks. Will also be watching developing line of convection across central Missouri for any potential of severe wind gusts or hail over the next few hours as it moves east. Issued at 853 PM CDT Wed Oct 1 2014 Forecast looks to be generally on track and I don`t foresee any major changes for the rest of the evening. Instability is waning, but obviously there`s enough to keep some rather strong storms going. Will most likely let WW511 expire naturally at 1000 PM. The challenge after 1000 PM will be trying to figure out exactly where the heaviest rain will fall for the rest of the night. It still looks like the best threat for heavy rain and training will be over parts of our central Missouri counties. RAP is persistently showing moderate to strong moisture convergence at 850mb. Storms this evening have been efficient rain producers, and I expect this will not change. No change to flash flood watch at this time, and will probably only tweak PoPs to match current radar trends. Carney && .SHORT TERM: (Through Thursday Night) Issued at 340 PM CDT Wed Oct 1 2014 Lots to keep track of in the next 24 to 36 hours. First: severe thunderstorms have developed along the outflow boundary in central Missouri left over from storms earlier today. Modest instability between 1000-1500 J/Kg combined with around 40 kts bulk shear have produced a supercell which is riding the boundary. A few more cells are developing ahead of the big storm and may continue to strengthen. Expect the severe threat to continue into the early to mid evening hours...generally along and south of I-70. Should see storms weaken within a few hours of sunset, but then the low level jet strengthens in southwest flow ahead of the broad trof over the Rockies and developing low level circulation over the Plains. This will bring the second area of concern into play: heavy rain. Thunderstorms this morning and now this current round of severe convection will saturate the ground and increase the potential for flash flooding. Aforementioned 30-40kt low level jet is bringing plenty of Gulf moisture up into the area. Forecast soundings show a warm cloud depth of nearly 12,000 FT and BUFKIT is indicating that individual convective elements may move very slowly and train over the same locations. Current QPF from WPC shows rainfall in excess of 3 inches over the next 24 hours with locally higher amounts in addition to what`s already fallen. Therefore have gone ahead and pushed a flash flood watch for parts of central, northeast, and east central Missouri. Watch may need to be extended further east or northeast tonight as the situation develops. Attention turns to tomorrow when the upper level trof moves into the Great Plains and the associated surface system moves from northern Oklahoma into eastern Iowa through the day. Our CWFA will be squarely in the warm sector through the day, and even if there are no breaks in the clouds temperatures should be at least between 80 and 85...if not a tad bit warmer. With warm, humid airmass in place, NAM is forecasting SBCAPE values in excess of 2500 J/Kg in some parts of the CWFA. With 30-40kts of deep layer shear, and the approaching shortwave becoming negatively tilted , this looks like a good setup for severe weather during the afternoon and evening hours. The shear vector looks like it will be parallel to the front so the most likely convective mode will be a squall line with bows and LEWPS possible. The front will sweep through the area overnight Thursday night and we should be into cold advection by 12Z Friday morning. Carney .LONG TERM: (Thursday through Next Wednesday) Issued at 403 PM CDT Wed Oct 1 2014 Fall returns with a vengeance Friday and Saturday. Temperatures will drop 25 to 30 degrees behind the front Friday and Saturday. It will also be pretty breezy behind the front on Friday. Forecast soundings show some pretty good mixing which is likely to produce wind gusts in excess of 30 mph. Guidance is hinting at lows in the 30s across most of the area on Saturday morning, and this looks reasonable given the strength of the cold advection. This could easily be the coolest night of the season so far. Temperatures slowly moderate Sunday through next Wednesday. The highly amplified upper level pattern featuring a strong vortex just north of the Great Lakes region and a longwave trof over the eastern 1/2 of the CONUS will slowly become more zonal through midweek. By Wednesday the flow aloft should be nearly zonal and low level warm advection will bring temperatures back to near or above normal. Carney && .AVIATION: (For the 06z TAFs through 06z Thursday Night) Issued at 1142 PM CDT Wed Oct 1 2014 Ongoing showers and thunderstorms have continued to lift a bit further northward, so only have vcts mention for taf sites along I-70 corridor through 12z Thursday. For KUIN, showers to persist with some thunderstorms through the early morning hours. Will see a break in the activity during the mid morning hours before more significant activity fires up ahead of cold front during the afternoon and evening hours. Winds to persist from the southeast then veer to the south by mid morning. As cold front approaches, winds to begin veering to the southwest between 23z Thursday and 03z Friday. Frontal passage will be beyond the forecast period. Specifics for KSTL: Ongoing showers and thunderstorms have continued to lift a bit further northward, so only have vcts mention for metro area through 12z Thursday. Will see a break in the activity during the mid morning hours before more significant activity fires up ahead of cold front after 21z Thursday. Winds to persist from the southeast then veer to the south 12z Thursday. As cold front approaches, winds to begin veering to the southwest between 23z Thursday and 03z Friday. Frontal passage will be around 09z Friday with precipitation tapering off. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FLASH FLOOD WATCH through this evening FOR Audrain MO-Boone MO- Callaway MO-Cole MO-Gasconade MO-Knox MO-Lewis MO-Lincoln MO-Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO- Pike MO-Ralls MO-Shelby MO-Warren MO. IL...FLASH FLOOD WATCH through this evening FOR Adams IL-Brown IL- Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Montgomery IL- Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1142 PM CDT Wed Oct 1 2014 .UPDATE: Issued at 853 PM CDT Wed Oct 1 2014 Forecast looks to be generally on track and I don`t foresee any major changes for the rest of the evening. Instability is waning, but obviously there`s enough to keep some rather strong storms going. Will most likely let WW511 expire naturally at 1000 PM. The challenge after 1000 PM will be trying to figure out exactly where the heaviest rain will fall for the rest of the night. It still looks like the best threat for heavy rain and training will be over parts of our central Missouri counties. RAP is persistently showing moderate to strong moisture convergence at 850mb. Storms this evening have been efficient rain producers, and I expect this will not change. No change to flash flood watch at this time, and will probably only tweak PoPs to match current radar trends. Carney && .SHORT TERM: (Through Thursday Night) Issued at 340 PM CDT Wed Oct 1 2014 Lots to keep track of in the next 24 to 36 hours. First: severe thunderstorms have developed along the outflow boundary in central Missouri left over from storms earlier today. Modest instability between 1000-1500 J/Kg combined with around 40 kts bulk shear have produced a supercell which is riding the boundary. A few more cells are developing ahead of the big storm and may continue to strengthen. Expect the severe threat to continue into the early to mid evening hours...generally along and south of I-70. Should see storms weaken within a few hours of sunset, but then the low level jet strengthens in southwest flow ahead of the broad trof over the Rockies and developing low level circulation over the Plains. This will bring the second area of concern into play: heavy rain. Thunderstorms this morning and now this current round of severe convection will saturate the ground and increase the potential for flash flooding. Aforementioned 30-40kt low level jet is bringing plenty of Gulf moisture up into the area. Forecast soundings show a warm cloud depth of nearly 12,000 FT and BUFKIT is indicating that individual convective elements may move very slowly and train over the same locations. Current QPF from WPC shows rainfall in excess of 3 inches over the next 24 hours with locally higher amounts in addition to what`s already fallen. Therefore have gone ahead and pushed a flash flood watch for parts of central, northeast, and east central Missouri. Watch may need to be extended further east or northeast tonight as the situation develops. Attention turns to tomorrow when the upper level trof moves into the Great Plains and the associated surface system moves from northern Oklahoma into eastern Iowa through the day. Our CWFA will be squarely in the warm sector through the day, and even if there are no breaks in the clouds temperatures should be at least between 80 and 85...if not a tad bit warmer. With warm, humid airmass in place, NAM is forecasting SBCAPE values in excess of 2500 J/Kg in some parts of the CWFA. With 30-40kts of deep layer shear, and the approaching shortwave becoming negatively tilted , this looks like a good setup for severe weather during the afternoon and evening hours. The shear vector looks like it will be parallel to the front so the most likely convective mode will be a squall line with bows and LEWPS possible. The front will sweep through the area overnight Thursday night and we should be into cold advection by 12Z Friday morning. Carney .LONG TERM: (Thursday through Next Wednesday) Issued at 403 PM CDT Wed Oct 1 2014 Fall returns with a vengeance Friday and Saturday. Temperatures will drop 25 to 30 degrees behind the front Friday and Saturday. It will also be pretty breezy behind the front on Friday. Forecast soundings show some pretty good mixing which is likely to produce wind gusts in excess of 30 mph. Guidance is hinting at lows in the 30s across most of the area on Saturday morning, and this looks reasonable given the strength of the cold advection. This could easily be the coolest night of the season so far. Temperatures slowly moderate Sunday through next Wednesday. The highly amplified upper level pattern featuring a strong vortex just north of the Great Lakes region and a longwave trof over the eastern 1/2 of the CONUS will slowly become more zonal through midweek. By Wednesday the flow aloft should be nearly zonal and low level warm advection will bring temperatures back to near or above normal. Carney && .AVIATION: (For the 06z TAFs through 06z Thursday Night) Issued at 1142 PM CDT Wed Oct 1 2014 Ongoing showers and thunderstorms have continued to lift a bit further northward, so only have vcts mention for taf sites along I-70 corridor through 12z Thursday. For KUIN, showers to persist with some thunderstorms through the early morning hours. Will see a break in the activity during the mid morning hours before more significant activity fires up ahead of cold front during the afternoon and evening hours. Winds to persist from the southeast then veer to the south by mid morning. As cold front approaches, winds to begin veering to the southwest between 23z Thursday and 03z Friday. Frontal passage will be beyond the forecast period. Specifics for KSTL: Ongoing showers and thunderstorms have continued to lift a bit further northward, so only have vcts mention for metro area through 12z Thursday. Will see a break in the activity during the mid morning hours before more significant activity fires up ahead of cold front after 21z Thursday. Winds to persist from the southeast then veer to the south 12z Thursday. As cold front approaches, winds to begin veering to the southwest between 23z Thursday and 03z Friday. Frontal passage will be around 09z Friday with precipitation tapering off. Byrd && .LSX WATCHES/WARNINGS/ADVISORIES: MO...FLASH FLOOD WATCH through Thursday evening FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Gasconade MO-Moniteau MO-Monroe MO- Montgomery MO-Osage MO. IL...NONE. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
251 AM CDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 SEVERAL TIMING ISSUES WILL BE THE MAIN CONCERN IN THE SHORT TERM. INITIAL FOCUS WILL BE BAND OF SHOWERS AND STORMS STARTING TO SPREAD INTO THE AREA AT 07Z FROM CENTRAL NEBRASKA. MODELS CONTINUE TO SUGGEST A STEADY PROGRESS OF THIS SYSTEM ACROSS THE CWA TODAY IN ADVANCE OF THE UPPER TROUGH. LATEST RAP HAS THE MAJORITY OF THE PRECIP EAST OF THE AREA BY 00Z. ALSO MAY NEED A MENTION OF FOG FOR A SHORT TIME THIS MORNING IN WEST CENTRAL IOWA BETWEEN HARLAN AND RED OAK WHERE VSBY IS REPORTED NEAR ZERO. WILL MONITOR UNTIL ISSUANCE FOR ANY CHANGE AS CLOUD COVER BEGINS TO SPREAD INTO THAT AREA. A NEW FEATURE THAT HAS SHOWN UP IN TONIGHTS MODELS IS A SECONDARY BAND OF SHOWERS BEHIND THE PRIMARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE AS IT MOVES INTO NEBRASKA TONIGHT. AT THIS POINT HAVE KEPT POPS ON THE LOW SIDE AND MAINLY FOR WESTERN AND SOUTHERN PARTS OF THE AREA AS INDICATED BY 00Z MODELS. OTHERWISE WEATHER TURNS WINDY AND COLD BEHIND THE FRONT TONIGHT INTO FRIDAY WITH GOOD POTENTIAL FOR FROST OR FREEZE ACROSS MOST OF THE AREA SATURDAY MORNING. AT THIS TIME WILL CONTINUE MENTION OF THIS POTENTIAL IN THE HWO AND WAIT UNTIL LATER FORECAST FOR HEADLINES. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 GENERALLY DRY AND WARMER IN THE EXTENDED PERIOD UNTIL TOWARDS THE END OF THE TIME FRAME WHEN ANOTHER FRONTAL SYSTEM WITH UPPER LEVEL SUPPORT DEVELOPS OVER THE REGION. POPS ON THE LOW SIDE FOR NOW DUE TO UNCERTAINTY IN POSTION AND TIMING. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1149 PM CDT WED OCT 1 2014 VFR CONDITIONS AT ALL TAF SITES. SHOWERS WILL AFFECT KOFK...WITH POSSIBLE TSRA THROUGH ABOUT 11Z. TSRA MAY IMPACT KLNK BY 09Z AND KOMA BY 10Z. ABOUT A 2-5 HOUR WIND FOR CONVECTION...THEN INSTABILITY MOVES EAST AND IT SHOULD END AS SHOWERS. SHOULD ALSO SEE MVFR CEILING DEVELOP. FOG COULD ALSO IMPACT KOMA BEFORE THE RAIN ARRIVES. WHEN THE REAL COLD FRONT ARRIVES...WINDS SUBSTANTIALLY INCREASE FROM THE NORTHWEST WITH GUSTS UP TO 20 TO 22 KNOTS...WITH WINDS BECOMING LESS THAN 10 KNOTS BY 00Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
310 AM EDT THU OCT 02 2014 .SYNOPSIS...WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA TODAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY... AND CROSS THE AREA FRIDAY NIGHT. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM THURSDAY... WEAK HIGH PRESSURE RIDGING HOLDS OVER NC THIS MORNING. FOG THUS FAR HAS BEEN A BIT LIGHTER AND MORE PATCHY THAN THIS TIME YESTERDAY... PERHAPS DUE IN PART TO AREAS OF SCT-BKN MID CLOUDS DRIFTING OVER THE AREA... ASSOCIATED WITH A WEAK MID LEVEL PERTURBATION PASSING ESE THROUGH THE REGION JUST EAST OF THE INCOMING MID LEVEL SHORTWAVE RIDGE. ADDITIONAL MID CLOUDS OVER NE NC AND TO THE NE ARE ASSOCIATED WITH THE MID LEVEL LOW JUST OFF NEW ENGLAND. WE MAY SEE A FEW SPRINKLES OVER NE PORTIONS OF THE FORECAST AREA EARLY THIS MORNING... BUT THE MOISTURE APPEARS TOO SHALLOW FOR ANY APPRECIABLE PRECIP. THE VERY LIGHT WIND FIELD IN THE LOW LEVELS SHOULD ONCE AGAIN MAKE FOR A SLOW DISSOLUTION OF THIS MORNING`S FOG... HOWEVER IF IT REMAINS MORE LIGHT AND PATCHY THROUGH DAYBREAK (IN CONTRAST TO THE HRRR WHICH DEPICTS WIDESPREAD LOW CIGS/VSBYS THROUGH SUNRISE)... WE WOULD THEN SEE SOME SUNSHINE EARLIER THAN YESTERDAY. REGARDLESS... FORECAST SOUNDINGS SHOW SUFFICIENT LOW LEVEL MOISTURE BENEATH THE SUBSIDENCE INVERSION ALOFT (JUST ABOVE 700 MB) FOR PARTLY CLOUDY SKIES FOR MUCH OF THE DAY. MANY OF THE CONVECTION ALLOWING MODELS AS WELL AS THE NAM/GFS AND SREF PROBABILITIES SUGGEST THAT A FEW SHALLOW SHOWERS WILL POP UP THIS AFTERNOON... PROMPTED BY HEATING WHICH SHOULD YIELD PERHAPS A FEW HUNDRED J/KG OF CAPE... ALMOST ALL BELOW 700 MB. THESE SHOWERS SHOULD BE ORIENTED ALONG THE DIFFUSE WARM FRONTAL ZONE MOVING NE THROUGH THE AREA LATE TODAY THROUGH TONIGHT. WILL BRING IN ISOLATED SHOWERS FROM MID-LATE AFTERNOON STRETCHING THROUGH THE EVENING AND EARLY OVERNIGHT HOURS. AS DEWPOINTS CREEP UPWARD A BIT OVERNIGHT IN THE WAKE OF THE WARM FRONTAL ZONE... EXPECT YET ANOTHER ROUND OF LIGHT FOG... BUT THIS FOG SHOULD STAY LIGHT GIVEN EXPECTATIONS OF STRATOCUMULUS TO CURB NOCTURNAL COOLING. HIGHS FROM 78 NE TO 84 SW... WITH THICKNESSES RUNNING NEARLY 10 M ABOVE NORMAL. MILD LOWS TONIGHT OF 60-64. -GIH && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 310 AM THURSDAY... LATEST MODEL OUTPUT ARE IN PRETTY CLOSE AGREEMENT ON THE TIMING OF POTENT MID LEVEL LOW ACROSS THE LOWER GREAT LAKES... ITS ATTENDING LARGE SCALE TROUGH PUSHING THROUGH EASTERN NOAM... AND THE ASSOCIATED SURFACE COLD FRONT. WE GET FULLY INTO THE WARM SECTOR DURING FRI MORNING... AND THE FRONT ITSELF SHOULD GET INTO WRN NC BY MID EVENING... AND THEN SWEEP EASTWARD OVERNIGHT... REACHING THE COASTAL PLAIN BY DAYBREAK. MOISTURE SPREADS IN FROM THE WEST AHEAD OF THE FRONT... WITH PW VALUES CLIMBING QUICKLY FROM AROUND 1 INCH TO AT OR ABOVE 1.5 INCHES DURING THE AFTERNOON HOURS. THE KINEMATICS WITH THIS SYSTEM ARE DECENT... WITH A 35-40 KT SWRLY LOW LEVEL JET ALIGNED JUST AHEAD OF THE SURFACE FRONT AND DEEP LAYER BULK SHEAR INCREASING TO 30 (EAST) TO 50 (EAST) KTS FRI NIGHT. BUT THE PROJECTED MUCAPE VALUES ARE MINOR... PEAKING AT JUST 250-500 J/KG... MADE WORSE BY THE LOSS OF HEATING WITH AN EVENING/NIGHT PASSAGE. DYNAMICS ARE BETTER BUT SIMILARLY MUTED... GIVEN THAT THE LEAD SHORTWAVE TRACKING ENE OVER NC IS RATHER WEAK... AND THE BULK OF THE HEIGHT FALLS ARE HELD TO OUR NW OVER THE MIDWEST AND OH VALLEY CLOSER TO THE MID LEVEL VORTEX. BUT GIVEN THE STRONG WIND FIELD AND UPPER DIVERGENCE MAX SHIFTING EAST THROUGH THE AREA... STILL EXPECT GOOD SHOWER/ISOLATED STORM COVERAGE. WILL BRING IN LOW CHANCE POPS WEST BY MID AFTERNOON... SPREADING EASTWARD WITH HIGH POPS TOPPING OUT AT 60-80% IN THE EVENING/OVERNIGHT... BEFORE STARTING TO PUSH OUT OF THE CWA TOWARD MORNING. OVERALL QPF LOOKS MEAGER WITH THIS EVENT... LIKELY TOTALLING A QUARTER INCH OR LESS. THE LOW POTENTIAL INSTABILITY WILL GREATLY CUT THE SEVERE THREAT... ALTHOUGH A FEW BOWING SEGMENTS MAY BRING DOWN SOME OF THE 30-40 KTS OF WIND FROM ALOFT... EVEN WITH JUST SHOWERS. HIGHS NEAR 80 NW (WHERE CLOUDS SHOULD BE FIRST TO SPREAD IN DURING THE AFTERNOON) TO 85 SE. LOWS 57 NW TO 66 SE. -GIH && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 230 AM THURSDAY... THE COLD FRONT WILL CONTINUE TO PROGRESS THROUGH CENTRAL NC EARLY SATURDAY...WITH THE PRE-FRONTAL CONVECTION ENDING FROM WEST TO EAST AHEAD OF IT...EXITING THE AREA BY NOON SATURDAY. ONCE THE RAIN ENDS SATURDAY...EXPECT DRY WEATHER THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THERE IS STILL SOME UNCERTAINTY IN THE RAINFALL CHANCES FOR TUESDAY AND WEDNESDAY AS ANOTHER DISTURBANCE TRAVERSES THE UPPER LEVEL TROUGH AND APPROACHES THE CAROLINAS. FOR NOW WILL KEEP THE FORECAST DRY. AT THE SURFACE...COOL HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT...MOVING NE OVER NC THROUGH THE WEEKEND AND OUT OVER THE ATLANTIC EARLY NEXT WEEK. EXPECT A RELATIVELY COOL AND COMFORTABLE TEMPERATURE FORECAST FOR THE WEEKEND...WITH HIGHS IN THE MID 60S TO LOW 70S SATURDAY AND MID 60S EVERYWHERE SUNDAY. SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE SEASON SO FAR...LOW 40S NW TO UPPER 40S SE. SUNDAY NIGHT WILL ALSO BE CHILLY...MID 40S ACROSS THE AREA. TEMPERATURES WILL REBOUND SOME EARLY NEXT WEEK... HIGHS MAINLY IN THE LOW 70S MONDAY INCREASING TO MID TO UPPER 70S BY WEDNESDAY. LOWS 50-55 DEGREES MONDAY NIGHT...INCREASING INTO THE 55- 60 DEGREE RANGE BY WEDNESDAY NIGHT. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 1235 AM THURSDAY... YET ANOTHER ROUND OF IFR/LIFR CONDITIONS WITH STRATUS AND FOG IS LIKELY TO DOMINATE THIS MORNING. WITH FAVORABLE CONDITIONS IN PLACE INCLUDING VERY LIGHT OR CALM WINDS AREAWIDE AND A LACK OF CLOUDS PROMOTING SURFACE COOLING DOWN TO THE DEWPOINTS... PATCHY DENSE FOG WITH VSBYS UNDER A HALF MILE IS LIKELY TO SPREAD AND FILL IN OVER NEARLY ALL OF CENTRAL NC EARLY IN THE TAF PERIOD. THESE ADVERSE AVIATION CONDITIONS ARE EXPECTED TO SLOWLY IMPROVE TO MVFR AT ALL SITES BETWEEN 13Z AND 15Z... AND TO VFR BY 17Z. RAIN CHANCES REMAIN VERY LOW AT CENTRAL NC TAF SITES... ALTHOUGH PASSAGE OF A WEAK UPPER LEVEL DISTURBANCE THIS MORNING COULD BRING AN ISOLATED SPRINKLE OR TWO TO RDU/RWI. AND ADDITIONAL ISOLATED VERY LIGHT (VFR) SHOWERS ARE POSSIBLE LATE THIS AFTERNOON ASSOCIATED WITH A WEAK WARM FRONT MOVING NORTHEASTWARD THROUGH THE AREA. WINDS WILL BE LARGELY CALM THROUGH MID MORNING... THEN REMAIN LIGHT/VARIABLE THIS AFTERNOON AND EVENING BUT PREDOMINANTLY FROM THE SE. PATCHY MVFR-IFR FOG MAY FORM ONCE AGAIN LATE IN THE TAF VALID PERIOD (AFTER 04Z FRI). LOOKING BEYOND 06Z EARLY FRI MORNING... PATCHY FOG SHOULD HOLD THROUGH DAYBREAK FRI MORNING... FOLLOWED BY IMPROVEMENT TO VFR DURING MID-LATE FRI MORNING. A STRONG FRONTAL SYSTEM WILL BRING INCREASING SURFACE WINDS FROM THE SW AND A GOOD CHANCE OF SUB-VFR CONDITIONS IN WIDESPREAD SHOWERS AND A FEW STORMS FRI EVENING THROUGH FRI NIGHT... EXITING THE EASTERN TAFS EARLY SAT MORNING. VFR CONDITIONS SHOULD THEN RESUME SAT AFTERNOON... LASTING THROUGH MONDAY... AS HIGH PRESSURE BUILDS IN FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...KC AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
240 AM EDT THU OCT 02 2014 .SYNOPSIS...WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA TODAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY... AND CROSS THE AREA FRIDAY NIGHT. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM THURSDAY... WEAK HIGH PRESSURE RIDGING HOLDS OVER NC THIS MORNING. FOG THUS FAR HAS BEEN A BIT LIGHTER AND MORE PATCHY THAN THIS TIME YESTERDAY... PERHAPS DUE IN PART TO AREAS OF SCT-BKN MID CLOUDS DRIFTING OVER THE AREA... ASSOCIATED WITH A WEAK MID LEVEL PERTURBATION PASSING ESE THROUGH THE REGION JUST EAST OF THE INCOMING MID LEVEL SHORTWAVE RIDGE. ADDITIONAL MID CLOUDS OVER NE NC AND TO THE NE ARE ASSOCIATED WITH THE MID LEVEL LOW JUST OFF NEW ENGLAND. WE MAY SEE A FEW SPRINKLES OVER NE PORTIONS OF THE FORECAST AREA EARLY THIS MORNING... BUT THE MOISTURE APPEARS TOO SHALLOW FOR ANY APPRECIABLE PRECIP. THE VERY LIGHT WIND FIELD IN THE LOW LEVELS SHOULD ONCE AGAIN MAKE FOR A SLOW DISSOLUTION OF THIS MORNING`S FOG... HOWEVER IF IT REMAINS MORE LIGHT AND PATCHY THROUGH DAYBREAK (IN CONTRAST TO THE HRRR WHICH DEPICTS WIDESPREAD LOW CIGS/VSBYS THROUGH SUNRISE)... WE WOULD THEN SEE SOME SUNSHINE EARLIER THAN YESTERDAY. REGARDLESS... FORECAST SOUNDINGS SHOW SUFFICIENT LOW LEVEL MOISTURE BENEATH THE SUBSIDENCE INVERSION ALOFT (JUST ABOVE 700 MB) FOR PARTLY CLOUDY SKIES FOR MUCH OF THE DAY. MANY OF THE CONVECTION ALLOWING MODELS AS WELL AS THE NAM/GFS AND SREF PROBABILITIES SUGGEST THAT A FEW SHALLOW SHOWERS WILL POP UP THIS AFTERNOON... PROMPTED BY HEATING WHICH SHOULD YIELD PERHAPS A FEW HUNDRED J/KG OF CAPE... ALMOST ALL BELOW 700 MB. THESE SHOWERS SHOULD BE ORIENTED ALONG THE DIFFUSE WARM FRONTAL ZONE MOVING NE THROUGH THE AREA LATE TODAY THROUGH TONIGHT. WILL BRING IN ISOLATED SHOWERS FROM MID-LATE AFTERNOON STRETCHING THROUGH THE EVENING AND EARLY OVERNIGHT HOURS. AS DEWPOINTS CREEP UPWARD A BIT OVERNIGHT IN THE WAKE OF THE WARM FRONTAL ZONE... EXPECT YET ANOTHER ROUND OF LIGHT FOG... BUT THIS FOG SHOULD STAY LIGHT GIVEN EXPECTATIONS OF STRATOCUMULUS TO CURB NOCTURNAL COOLING. HIGHS FROM 78 NE TO 84 SW... WITH THICKNESSES RUNNING NEARLY 10 M ABOVE NORMAL. MILD LOWS TONIGHT OF 60-64. -GIH && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 245 PM WEDNESDAY... FRIDAY INTO EARLY SATURDAY: THE TIMING OF THE MAIN COLD FRONT ALONG WITH POTENTIAL CONVECTIVE OUTFLOW BOUNDARIES WILL BE THE MAIN CONCERNS FRIDAY AFTERNOON AND FRIDAY NIGHT. THEY WILL BE THE DRIVING MECHANISMS FOR SHOWERS AND SCATTERED THUNDERSTORMS. AS IT CURRENTLY APPEARS...THE MAIN THREAT OF CONVECTION SHOULD HOLD OFF UNTIL LATE IN THE AFTERNOON IN THE WEST...AND UNTIL THE EVENING IN THE CENTRAL AND EAST. SOME MODELS SUGGEST THAT THE FAYETTEVILLE TO GOLDSBORO AREAS MAY NOT SEE THE CHANCE OF SHOWERS/THUNDER UNTIL LATE EVENING AND OVERNIGHT. THERE CONTINUES TO BE QUITE A SPREAD IN THE MODELS WITH THE DETAILS OF TIMING AND QPF ASSOCIATED WITH THE FRONT... EVEN THOUGH THEY ARE TRENDING TOWARD THE AFOREMENTIONED SOLUTION. FOR NOW... FRIDAY APPEARS THAT IT WILL BE PARTLY SUNNY AND WARM WITH HIGHS IN THE LOWER 80S... EXCEPT 75-80 IN THE NORTHWEST PIEDMONT. POP WILL INCREASE FROM WEST TO EAST DURING THE LATE AFTERNOON INTO THE EVENING WITH THE TIME FRAME OF 400 PM THROUGH MIDNIGHT HIGHEST POP IN THE WEST... AND 800 PM THROUGH 400 AM HIGHEST IN THE CENTRAL AND EAST. A LEAD CONVECTIVE LINE MAY RIDE OUT AHEAD OF THE FRONT ALONG ASSOCIATED OUTFLOW BOUNDARIES... FOLLOWED BY CONVECTION ALONG THE FRONT ITSELF. QPF APPEARS TO BE ON THE ORDER OF 0.25 TO 0.50 IN THE WESTERN PIEDMONT... WITH AVERAGE AMOUNTS AROUND 0.25 IN THE SE (DUE TO WEAKENING OF THE CONVECTION DUE TO OVERNIGHT TIMING IN THE EASTERN ZONES). THE SEVERE THREAT APPEARS MINIMAL WITH ONLY MODEST INSTABILITY AND WEAK SHEAR EXPECTED. ALSO... TIMING OF THE CONVECTION FRIDAY NIGHT IN THE EAST WILL BE LATER INTO THE NOCTURNAL CYCLE... THUS THE WEAKENING TREND EXPECTED. -PWB && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 230 AM THURSDAY... THE COLD FRONT WILL CONTINUE TO PROGRESS THROUGH CENTRAL NC EARLY SATURDAY...WITH THE PRE-FRONTAL CONVECTION ENDING FROM WEST TO EAST AHEAD OF IT...EXITING THE AREA BY NOON SATURDAY. ONCE THE RAIN ENDS SATURDAY...EXPECT DRY WEATHER THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THERE IS STILL SOME UNCERTAINTY IN THE RAINFALL CHANCES FOR TUESDAY AND WEDNESDAY AS ANOTHER DISTURBANCE TRAVERSES THE UPPER LEVEL TROUGH AND APPROACHES THE CAROLINAS. FOR NOW WILL KEEP THE FORECAST DRY. AT THE SURFACE...COOL HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT...MOVING NE OVER NC THROUGH THE WEEKEND AND OUT OVER THE ATLANTIC EARLY NEXT WEEK. EXPECT A RELATIVELY COOL AND COMFORTABLE TEMPERATURE FORECAST FOR THE WEEKEND...WITH HIGHS IN THE MID 60S TO LOW 70S SATURDAY AND MID 60S EVERYWHERE SUNDAY. SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE SEASON SO FAR...LOW 40S NW TO UPPER 40S SE. SUNDAY NIGHT WILL ALSO BE CHILLY...MID 40S ACROSS THE AREA. TEMPERATURES WILL REBOUND SOME EARLY NEXT WEEK... HIGHS MAINLY IN THE LOW 70S MONDAY INCREASING TO MID TO UPPER 70S BY WEDNESDAY. LOWS 50-55 DEGREES MONDAY NIGHT...INCREASING INTO THE 55- 60 DEGREE RANGE BY WEDNESDAY NIGHT. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... AS OF 1235 AM THURSDAY... YET ANOTHER ROUND OF IFR/LIFR CONDITIONS WITH STRATUS AND FOG IS LIKELY TO DOMINATE THIS MORNING. WITH FAVORABLE CONDITIONS IN PLACE INCLUDING VERY LIGHT OR CALM WINDS AREAWIDE AND A LACK OF CLOUDS PROMOTING SURFACE COOLING DOWN TO THE DEWPOINTS... PATCHY DENSE FOG WITH VSBYS UNDER A HALF MILE IS LIKELY TO SPREAD AND FILL IN OVER NEARLY ALL OF CENTRAL NC EARLY IN THE TAF PERIOD. THESE ADVERSE AVIATION CONDITIONS ARE EXPECTED TO SLOWLY IMPROVE TO MVFR AT ALL SITES BETWEEN 13Z AND 15Z... AND TO VFR BY 17Z. RAIN CHANCES REMAIN VERY LOW AT CENTRAL NC TAF SITES... ALTHOUGH PASSAGE OF A WEAK UPPER LEVEL DISTURBANCE THIS MORNING COULD BRING AN ISOLATED SPRINKLE OR TWO TO RDU/RWI. AND ADDITIONAL ISOLATED VERY LIGHT (VFR) SHOWERS ARE POSSIBLE LATE THIS AFTERNOON ASSOCIATED WITH A WEAK WARM FRONT MOVING NORTHEASTWARD THROUGH THE AREA. WINDS WILL BE LARGELY CALM THROUGH MID MORNING... THEN REMAIN LIGHT/VARIABLE THIS AFTERNOON AND EVENING BUT PREDOMINANTLY FROM THE SE. PATCHY MVFR-IFR FOG MAY FORM ONCE AGAIN LATE IN THE TAF VALID PERIOD (AFTER 04Z FRI). LOOKING BEYOND 06Z EARLY FRI MORNING... PATCHY FOG SHOULD HOLD THROUGH DAYBREAK FRI MORNING... FOLLOWED BY IMPROVEMENT TO VFR DURING MID-LATE FRI MORNING. A STRONG FRONTAL SYSTEM WILL BRING INCREASING SURFACE WINDS FROM THE SW AND A GOOD CHANCE OF SUB-VFR CONDITIONS IN WIDESPREAD SHOWERS AND A FEW STORMS FRI EVENING THROUGH FRI NIGHT... EXITING THE EASTERN TAFS EARLY SAT MORNING. VFR CONDITIONS SHOULD THEN RESUME SAT AFTERNOON... LASTING THROUGH MONDAY... AS HIGH PRESSURE BUILDS IN FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...PWB LONG TERM...KC AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
311 AM CDT THU OCT 2 2014 .DISCUSSION... A TRICKY SEVERE WEATHER FORECAST FOR THIS AFTERNOON INTO TONIGHT. CURRENTLY...A COLD FRONT STRETCHES FROM KANSAS CITY MISSOURI TO NEAR AMARILLO TEXAS. LIGHT SOUTHERLY WINDS CONTINUE TO BRING AN INCREASE IN MOISTURE FROM THE GULF OF MEXICO. DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 60S BUT SHOULD JUMP INTO THE UPPER 60S TO LOWER 70S BY THIS AFTERNOON. LOW CLOUDS ARE RAPIDLY DEVELOPING ACROSS LOUISIANA INTO CENTRAL/SOUTHERN MISSISSIPPI. MODELS INDICATE THE CLOUDS SHOULD SPREAD ACROSS THE CWA BETWEEN 6AM-9AM. LATEST HRRR SHOWS SHOWERS SHOULD START POPPING ACROSS NORTH MISSISSIPPI BY 8 AM. BY 11AM-1PM...SHOWERS AND THUNDERSTORMS WILL RAPIDLY DEVELOP ACROSS MOST OF THE CWA AND WILL CONTINUE THROUGH THE REST OF THE AFTERNOON. THE LATEST GFS..NAM...AND ECMWF SEEM TO FALL IN LINE IN WHAT THE HRRR IS SHOWING THUS HAVE INCREASED POPS TO 60S ACROSS MUCH OF THE CWA FROM MID-MORNING INTO THE AFTERNOON. THE LOW CLOUDS MAY HANG TOUGH INTO THE AFTERNOON HOURS. THIS MAY HINDER ANY THUNDERSTORMS FROM BECOMING STRONG OR SEVERE AT LEAST DURING THE AFTERNOON HOURS. WITH ALL THE CONVECTION AND CLOUD COVER EXPECTED...HAVE KNOCKED DOWN HIGHS TODAY A TAD. DON/T REALLY SEE ANY LOCATION HITTING 90 TODAY. HIGHS SHOULD STAY IN THE MID TO UPPER 80S. SQUALL LINE IS STILL EXPECTED TO DEVELOP ALONG THE FRONT DURING THE AFTERNOON AND LATEST HRRR SHOWS IT STRETCHING FROM TULSA OKLAHOMA TO NEAR ABILENE TEXAS AROUND 2 PM. THE LINE WILL MOVE PROGRESS EASTWARD DURING THE REST OF THE AFTERNOON INTO THE EVENING HOURS. THE LINE WILL LIKELY OUTRACE THE FRONT BY THE EVENING HOURS. EXPECT BY THE TIME IT REACHES THE MIDSOUTH...IT MAY ENCOUNTER AN ATMOSPHERE AT LEAST SLIGHT WORKED OVER FROM CONVECTION THAT WILL OCCUR TODAY AND NOT AS UNSTABLE AS PREVIOUSLY THOUGHT A FEW DAYS AGO DUE TO CLOUD COVER. CAPE VALUES MAY GET TO 1500 J/KG WHICH IS STILL DECENT BUT NOT LIKE 2200 J/KG OR GREATER THAT THE NAM HAS BEEN SHOWING. MODELS ALSO CONTINUE TO BE A LITTLE SLOWER WITH TIMING. LINE MAY NOT GET INTO NORTHEAST ARKANSAS UNTIL CLOSER TO 9-10 PM. THUS INSTABILITY WILL BE WANING FROM LOSS OF DAYTIME HEATING. STILL EXPECT EASTERN ARKANSAS AND THE MISSOURI BOOTHEEL TO SEE THE BEST CHANCE OF SEEING SEVERE STORMS BUT REALLY EXPECT LINE TO START WEAKENING AS IT PUSHES EAST ESPECIALLY ONCE IT PUSHES EAST OF THE MISSISSIPPI RIVER. MAIN THREAT FROM THE LINE WILL BE DAMAGING WINDS AND LARGE HAIL. SINCE TIMING IS SLOWER HAVE HAD TO UPDATE POPS FOR FRIDAY TO KEEP THEM IN LONGER. NORTH MISSISSIPPI COULD SEE SOME REDEVELOPMENT OF THUNDERSTORMS ALONG THE FRONT DURING THE AFTERNOON HOURS. WOULD NOT BE SURPRISED IF SOME OF THESE BECAME STRONG WITH GUSTY WINDS AND SMALL HAIL. HIGH PRESSURE WILL BUILD INTO THE MIDSOUTH FOR THE WEEKEND AND WILL BRING BEAUTIFUL AUTUMN TEMPERATURES. HIGHS ON SATURDAY WILL BE IN THE MID TO UPPER 60S. LOWS SATURDAY NIGHT WILL DROP DOWN INTO THE UPPER 30S TO MID 40S. TEMPERATURES WILL JUMP BACK INTO THE 70S ON SUNDAY AS THE HIGH SHIFTS EAST. MODELS STILL DIFFER ON TIMING OF THE NEXT COLD FRONT FOR EARLY NEXT WEEK. THE ECMWF INDICATES FRONT WILL COME THROUGH SUNDAY NIGHT THROUGH MONDAY NIGHT. GFS HAS TIMING OF MONDAY NIGHT INTO TUESDAY. FOR NOW HAVE LEFT POPS AS IS WITH SMALL CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MONDAY INTO TUESDAY. DON/T REALLY EXPECT ANY COOL DOWN BEHIND THE FRONT AS AN UPPER RIDGE WILL BEGIN TO BUILD INTO THE AREA BEHIND IT. TEMPERATURES WILL LIKELY BE BACK INTO THE 80S BY WEDNESDAY. KRM && .AVIATION... 06Z TAF CYCLE VFR CONDITIONS WILL CONTINUE TONIGHT. OCCASIONAL MVFR CEILINGS SPREADING INTO THE REGION FROM THE SOUTHWEST BETWEEN 02/13Z AND 02Z/17Z ALONG WITH SCATTERED SHOWERS. AFTER 02Z/17Z CEILINGS LIFTING TO VFR BUT SCATTERED THUNDERSTORMS DEVELOPING. THUNDERSTORMS BECOMING MORE NUMEROUS AFTER 03/03Z AS A STRONG COLD FRONT APPROACHES FROM THE WEST. WINDS TONIGHT SE 3-7 KTS. WINDS THURSDAY S-SW INCREASING TO 10-15 KTS WITH GUSTS TO NEAR 22 KTS AT KJBR. WINDS AFTER 03/00Z S 7-10 KTS. JCL && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
325 AM CDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 325 AM CDT THU OCT 2 2014 IMMEDIATE CONCERNS INCLUDE FOG THIS MORNING AND INCOMING RAIN. SURFACE MAP EARLY THIS MORNING HAS A WEAK TROUGH EXTENDING N-S ACROSS MN/IA. WEAKLY CONVERGENT AND VERY DAMP LOWER BOUNDARY LAYER HAS LED TO SOME AREAS OF DENSE FOG ACROSS PORTIONS OF NORTHEAST IA/SOUTHEAST MN AND WEST CENTRAL WI. AS A RESULT...A DENSE FOG ADVISORY IS IN EFFECT UNTIL 10 AM. OTHERWISE...WATER VAPOR AND RAP 500MB ANALYSIS SHOWING A DEEPENING LONG WAVE BASICALLY ALONG THE SPINE OF THE ROCKY MOUNTAINS. AT THE SURFACE...CYCLOGENESIS WAS TAKING PLACE OVER THE TX/OK PANHANDLE. LIFT AHEAD OF THIS TROUGH AND SURFACE LOW WAS PRODUCING SCATTERED SHOWERS AN THUNDERSTORMS ACROSS THE PLAINS/MID-MISSISSIPPI RIVER VALLEY REGION. OVER THE LOCAL AR X FORECAST AREA...BESIDES THE FOG...SKIES WERE MOSTLY CLOUDY WITH TEMPERATURES IN THE 50S TO THE LOWER 60S. FOR TODAY...WILL BE WATCHING THE LOW OVER THE TX/OK PANHANDLE LIFT NORTHEAST IN MO BY NOON AND NORTHERN IL BY EARLY THIS EVENING. AS THIS OCCURS...850 MB MOISTURE TRANSPORT/850-500MB FRONTOGENESIS AND ISENTROPIC LIFT WILL ALL COMBINE FORCES TO SPREAD SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA... BECOMING MORE WIDESPREAD IN THE AFTERNOON. OTHERWISE...EXPECT HIGHS TO TOP OFF IN THE MIDDLE 60S TO THE LOWER 70S. FOR TONIGHT...THE LOW WILL CONTINUE TO LIFT NORTHEAST ACROSS EASTERN WI. THIS PUTS ARX FORECAST AREA UNDER FAIRLY STRONG 850-500MB FRONTOGENETIC BAND IN THE 00-06Z TIME FRAME. THIS IS EXPECTED TO DRIVE WIDESPREAD MODERATE RAINFALL WITH AMOUNTS LIKELY RANGING FROM 1/4 TO 1/2 INCH. THEN AFTER MIDNIGHT...PLAN ON RAIN TAPERING OFF FROM WEST TO EAST AS THE LOW PULLS INTO EASTERN LAKE SUPERIOR. STRENGTHENING PRESSURE GRADIENT ACROSS THE AREA IN THE WAKE OF THE LOW WILL PRODUCE INCREASING NORTHWEST WINDS THROUGH THE OVERNIGHT HOURS. COLD AIR ADVECTION WILL DROP TEMPERATURES INTO THE MIDDLE 40S TO AROUND THE 50 DEGREE MARK. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 325 AM CDT THU OCT 2 2014 GUSTY NORTHWEST WINDS WILL OVERSPREAD THE AREA IN THE WAKE OF DEEPENING SURFACE LOW PULLING INTO EASTERN ONTARIO. PLAN ON SUSTAINED WIND SPEEDS IN THE 15 TO 25 MPH RANGE WITH GUSTS 25 TO 35 MPH. PV-ADVECTION ASSOCIATED WITH INCOMING MID-LEVEL LOW WILL ALSO PRODUCE A CHANCE OF SHOWERS MAINLY EAST OF THE MISSISSIPPI RIVER. COLDER TEMPERATURES/GUSTY NORTHWEST WINDS/RAIN SHOWERS WILL ALL COMBINE FOR A PRETTY RAW DAY. AS THE MID-LEVEL LOW ROTATES SOUTHEAST ACROSS THE AREA SATURDAY NIGHT...LOOKING FOR SCATTERED SHOWERS TO RESULT. AS TEMPERATURES COOL INTO THE MID/UPPER 30S LATER IN THE NIGHT...THERE IS THE POSSIBILITY OF A FEW SNOW FLAKES MIXING IN AT TIMES. RAIN SHOWERS WILL STILL BE POSSIBLE ON SATURDAY MAINLY EAST OF THE MISSISSIPPI RIVER IN COLD CYCLONIC FLOW. OTHERWISE...ANOTHER RAW AUTUMN DAY ON TAP AS HIGHS ONLY TOP OFF IN THE MIDDLE/UPPER 40S. CONTINUED COLD AIR ADVECTION SATURDAY NIGHT WILL DROP TEMPERATURES NEAR THE FREEZING MARK FOR A GOOD PART OF THE AREA. LONG WAVE TROUGH/CLOSED LOW WILL LINGER ACROSS THE REGION THROUGH MONDAY FOR BELOW NORMAL TEMPERATURES. AN EMBEDDED SHORTWAVE TROUGH LOOKS TO MAKE PASSAGE ACROSS THE AREA ON MONDAY FOR A CHANCE OF SHOWERS. OTHERWISE...PLAN ON HIGHS SUNDAY AND MONDAY IN THE MIDDLE 40S TO THE MIDDLE 50S WITH OVERNIGHT LOWS IN THE 30S. FOR TUESDAY AND WEDNESDAY...THE CLOSED LOW FILLS AND LIFTS NORTHEAST INTO CANADA WITH HEIGHTS BUILDING IN FROM THE WEST. THIS IS EXPECTED TO PRODUCE A SLOW MODERATION IN TEMPERATURES WITH HIGHS IN THE 50S/FEW LOWER 60S TUESDAY...AND IN THE 60S WEDNESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT) ISSUED AT 1138 PM CDT WED OCT 1 2014 CONFIDENCE INCREASING FOR WIDESPREAD DENSE FOG AT TAF AIRFIELDS GIVEN SATURATED NEAR SURFACE LAYER...CLEARING SKIES ALOFT AND VERY LIGHT WIND. EXPECT FOG TO RAPIDLY DEVELOP BETWEEN 02.08Z TO 02.10Z WITH VISIBILITY DROPPING BELOW 1/4SM AND CEILINGS FROM 100 TO 200 FT AGL. FOG TO GRADUALLY DISSIPATE BETWEEN 02.15Z AND 02.16Z BEFORE MVFR/IFR CONDITIONS PERSIST THROUGH THE AFTERNOON AND INTO THE EVENING WITH RAIN SHOWERS INCREASING FROM SOUTHWEST TO NORTHEAST AS A STRONG LOW PRESSURE SYSTEM MOVES ACROSS THE REGION. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR WIZ032. MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR MNZ079-086>088- 094-095. IA...DENSE FOG ADVISORY UNTIL 10 AM CDT THURSDAY FOR IAZ008-009-018- 019. && $$ SHORT TERM...DAS LONG TERM...DAS AVIATION...ROGERS
AREA FORECAST DISCUSSION
NWS NEW YORK NY
753 AM EDT THU OCT 2 2014 .SYNOPSIS... AN UPPER LEVEL LOW WILL SLOWLY MOVE EAST TODAY...WITH HIGH PRESSURE BUILDING BRIEFLY IN ITS WAKE THROUGH FRIDAY. A COLD FRONT WILL PASS ON SATURDAY...FOLLOWED BY HIGH PRESSURE FOR SUNDAY AND MONDAY. WEAK LOW PRESSURE WILL AFFECT THE REGION ON TUESDAY...WITH A WEAK COLD FRONTAL PASSAGE LATE AT NIGHT. HIGH PRESSURE WILL RETURN ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FCST ADJUSTED TO CURRENT OBSERVATION AND TRENDS. RAIN CONFINED TO THE TWIN FORKS OF LONG ISLAND DRIFTING WEST SOUTHWEST. ELSEWHERE IT`S DRY WITH SOME SPOTTY DRIZZLE. THUS HAVE INCREASED POPS FOR EASTERN LONG ISLAND AND REMOVED POPS ELSEWHERE. LATEST HRRR SUPPORTS THE IDEA THAT PCPN DISSIPATES BY LATE MORNING. THUS HAVE RAPIDLY LOWERED POPS FOR EASTERN LONG ISLAND. OTHERWISE...UPPER LEVEL LOW SLOWLY PIVOTING THROUGH THE NORTHEAST. ASSOCIATED VORT MAX ALMOST STATIONARY OVER SOUTHERN NEW ENGLAND...WITH THE 00Z MODELS SUGGESTING IT PUSHING TO THE SOUTH THIS MORNING...THEN PUSHING OFFSHORE TO THE EAST AS THE LOW SLIPS TO THE EAST THROUGHOUT THE DAY. NE FLOW WILL KEEP A FAIRLY MOIST LOWER LEVEL IN PLACE BUT GENERALLY THINKING THE LOSS OF FORCING ALOFT WILL MINIMIZE THE PCPN CHANCES. SOME UNCERTAINTY WITH HIGH TEMPS FOR TONIGHT AS WEAK WAA WOULD SUGGEST TEMPS COULD PUSH NEAR NORMAL. HOWEVER...CLOUDY SKIES AND PERSISTENT NE FLOW COULD KEEP TEMPS ON THE SLIGHTLY COOLER SIDE. SIDED MORE WITH THE MAV GUIDANCE TO REFLECT THIS POSSIBILITY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... ANY LINGERING PCPN BY THIS EVENING SHOULD BE OFFSHORE SOUTH OF LONG ISLAND WITH DRY WX THEN ON TAP THROUGH FRIDAY. A SLIVER OF HIGH PRESSURE BRIEFLY BUILDS SOUTH FROM CANADA TONIGHT/FRIDAY BEFORE RETREATING ONCE AGAIN AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM FOR THE WEEKEND. UPPER LEVEL RIDGING BUILDS IN AS WELL DURING THIS TIME...WITH THE RIDGE AXIS SHIFTING THROUGH THE NORTHEAST DURING THE DAY FRIDAY. PLENTY OF SUBSIDENCE ALOFT...SO SHOULD SEE CLEARING SKIES FOR A SHORT PERIOD LATE TONIGHT/FRIDAY MORNING BEFORE HIGH LEVEL CLOUDS BEGIN STREAMING IN AHEAD OF THE LOW. WITH DRIER AIR MOVING IN WITH THE HIGH AS WELL...NOT ANTICIPATING MUCH IN THE FORM OF FOG DEVELOPMENT TONIGHT. HAVE MORE OF A HANDLE ON TEMPS FOR TONIGHT/TOMORROW...USING GENERALLY A BLEND OF THE MET/MAV GUIDANCE. TEMPS TONIGHT EXPECTED TO BE RIGHT AROUND NORMAL TO SLIGHTLY ABOVE. WITH MOSTLY SUNNY SKIES ON FRIDAY AND WAA...SHOULD SEE HIGHS A FEW DEGREES WARMER THAN TODAY. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... ALL NWP GUIDANCE REMAINS VERY CONSISTENT WITH A COLD FROPA ON SATURDAY. PCPN MOVES IN FROM WEST TO EAST IN THE MORNING AND EXITS IN THE AFTN WITH CLEARING QUICKLY DEVELOPING BY SATURDAY EVENING. HAVE CUT PREVIOUS FORECAST QPF IN COORDINATION WITH RIVER FORECAST CENTERS. EXPECTING AROUND 1/2 INCH WITH 3/4 INCH UP IN THE LOWER HUDSON VALLEY. NO HYDRO ISSUES EXPECTED. HIGH PRESSURE FOR SUNDAY AND MONDAY. CLOUDS START INCREASING LATE MONDAY WITH WAA. OVER-RUNNING PATTERN CONTINUES ON TUES WITH CHC POPS FOR LGT RA. WEAK AND DIFFUSE COLD FROPA PASSAGE EARLY WEDNESDAY MORNING WITH HIGH PRESSURE BUILDING IN. HAVE MADE IT DRY ON WEDNESDAY WITH TIMING OF COLD FROPA. LOWERED TEMPS AND MADE FOR NON-DIURNAL PATTERN ON SATURDAY WITH THE PCPN. BELOW NORMAL TEMPS ON SUNDAY...BUT WE QUICKLY RETURN TO NORMAL ON MONDAY AND THEN A BIT ABOVE NORMAL FOR TUESDAY AND WEDNESDAY. NO HAZARDS FORESEEN THROUGH WEDNESDAY. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... LOW PRESSURE WELL E OF CAPE COD WILL REMAIN NEARLY STATIONARY... WHILE AN UPPER LEVEL LOW OVER THE AREA MOVES TO THE EAST... ALLOWING HIGH PRESSURE TO BUILD DOWN FROM NEW ENGLAND. MVFR CIGS SHOULD BE WIDESPREAD TODAY...NOT LIFTING TO VFR UNTIL 19Z-22Z FROM WEST TO EAST. N-NE FLOW WILL INCREASE TO 10-15 KT THIS MORNING...WITH AN OCNL GUST UP TO 20 KT ESPECIALLY ALONG THE COAST...THEN DIMINISHING TO UNDER 10 KT AS VFR CONDS ARRIVE. ...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: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT. KLGA FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT. KEWR FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT. KHPN FCSTER COMMENTS: MVFR CIGS COULD BE PREVAILING FROM LATE MORNING INTO EARLY AFTERNOON. KISP FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT. .OUTLOOK FOR 12Z FRI THROUGH MON... .FRI...VFR. .FRI NIGHT...MVFR CONDS POSSIBLE LATE AT THE NYC METRO AND LOWER HUDSON VALLEY TERMINALS. .SAT...RAIN WITH IFR CONDS AND SE WINDS 15-20G25KT. COLD FROPA MID TO LATE AFTERNOON AT THE NYC METRO AND LOWER HUDSON VALLEY TERMINALS...FOLLOWED BY VFR CONDS AND W WIND G20KT. .SAT NIGHT...RAIN WITH IFR CONDS EARLY AT THE CT/LONG ISLAND TERMINALS...THEN COLD FROPA WITH IMPROVEMENT TO VFR. POST-FRONTAL W WINDS G25KT. .SUNDAY...VFR. W WINDS G20KT. .MON...VFR. && .MARINE... MINIMAL SCA REMAINS IN EFFECT FOR ALL THE WATERS LESS THE GREAT SOUTH BAY...NY HARBOR AND THE WESTERN SOUND AS NE FLOW INCREASES BETWEEN THE LOW OFFSHORE AND THE HIGH DIGGING DOWN FROM THE NORTH. GUSTS BETWEEN 23 TO 28 KT EXPECTED DURING THE DAY TODAY...THEN DIMINISHING TONIGHT AS THE PRESSURE GRADIENT WEAKENS WITH HIGH BUILDING FURTHER OVER THE WATERS. SEAS BUILD TODAY WITH THE STRENGTHENING FLOW...WITH 5-9 FT POSSIBLE ON THE OCEAN WATERS. OCNL GUSTS UP TO 25 KT WILL BE POSSIBLE THIS EVENING/EARLY OVERNIGHT FOR THE BAYS AND LONG ISLAND SOUND. THOUGH CONFIDENCE IS NOT ENOUGH TO EXTEND THE SCA AT THIS TIME OVER THOSE WATERS. STILL EXPECTING GUSTS TO 25 KT AND SEAS ABOVE 5 FT ON THE OCEAN...AND IN FACT EXPECTING THE 5 FT SEAS TO CONTINUE SO EXTENDED THE SCA OVER THE OCEAN FOR FRIDAY. ON THE OCEAN...SCA CONDS CAN BE EXPECTED THRU NEXT WED...WITH PERHAPS A BRIEF RESPITE FOR PORTIONS OF MON. ELSEWHERE...25KT WINDS POSSIBLE SAT-SUN BOTH AHEAD OF AND BEHIND A CDFNT. OTHERWISE THEY WILL GENERALLY BE IN THE 10-20KT RANGE. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH FRI EVENING. EXPECTING AROUND 1/2 INCH WITH 3/4 UP IN THE LOWER HUDSON VALLEY DURING THE DAY ON SATURDAY. LIGHT RAIN IS POSSIBLE FOR TUESDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330- 340. && $$ SYNOPSIS...SEARS/TONGUE NEAR TERM...SEARS/TONGUE SHORT TERM...SEARS LONG TERM...TONGUE AVIATION...GOODMAN MARINE...SEARS/TONGUE HYDROLOGY...SEARS/TONGUE
AREA FORECAST DISCUSSION
NWS NEW YORK NY
719 AM EDT THU OCT 2 2014 .SYNOPSIS... AN UPPER LEVEL LOW WILL SLOWLY MOVE EAST TODAY...WITH HIGH PRESSURE BUILDING BRIEFLY IN ITS WAKE THROUGH FRIDAY. A COLD FRONT WILL PASS ON SATURDAY...FOLLOWED BY HIGH PRESSURE FOR SUNDAY AND MONDAY. WEAK LOW PRESSURE WILL AFFECT THE REGION ON TUESDAY...WITH A WEAK COLD FRONTAL PASSAGE LATE AT NIGHT. HIGH PRESSURE WILL RETURN ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FCST ADJUSTED TO CURRENT OBSERVATION AND TRENDS. RAIN CONFINED TO THE TWIN FORKS OF LONG ISLAND DRIFTING WEST SOUTHWEST. ELSEWHERE IT`S DRY WITH SOME SPOTTY DRIZZLE. THUS HAVE INCREASED POPS FOR EASTERN LONG ISLAND AND REMOVED POPS ELSEWHERE. LATEST HRRR SUPPORTS THE IDEA THAT PCPN DISSIPATES BY LATE MORNING. THUS HAVE RAPIDLY LOWERED POPS FOR EASTERN LONG ISLAND. OTHERWISE...UPPER LEVEL LOW SLOWLY PIVOTING THROUGH THE NORTHEAST. ASSOCIATED VORT MAX ALMOST STATIONARY OVER SOUTHERN NEW ENGLAND...WITH THE 00Z MODELS SUGGESTING IT PUSHING TO THE SOUTH THIS MORNING...THEN PUSHING OFFSHORE TO THE EAST AS THE LOW SLIPS TO THE EAST THROUGHOUT THE DAY. NE FLOW WILL KEEP A FAIRLY MOIST LOWER LEVEL IN PLACE BUT GENERALLY THINKING THE LOSS OF FORCING ALOFT WILL MINIMIZE THE PCPN CHANCES. SOME UNCERTAINTY WITH HIGH TEMPS FOR TONIGHT AS WEAK WAA WOULD SUGGEST TEMPS COULD PUSH NEAR NORMAL. HOWEVER...CLOUDY SKIES AND PERSISTENT NE FLOW COULD KEEP TEMPS ON THE SLIGHTLY COOLER SIDE. SIDED MORE WITH THE MAV GUIDANCE TO REFLECT THIS POSSIBILITY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... ANY LINGERING PCPN BY THIS EVENING SHOULD BE OFFSHORE SOUTH OF LONG ISLAND WITH DRY WX THEN ON TAP THROUGH FRIDAY. A SLIVER OF HIGH PRESSURE BRIEFLY BUILDS SOUTH FROM CANADA TONIGHT/FRIDAY BEFORE RETREATING ONCE AGAIN AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM FOR THE WEEKEND. UPPER LEVEL RIDGING BUILDS IN AS WELL DURING THIS TIME...WITH THE RIDGE AXIS SHIFTING THROUGH THE NORTHEAST DURING THE DAY FRIDAY. PLENTY OF SUBSIDENCE ALOFT...SO SHOULD SEE CLEARING SKIES FOR A SHORT PERIOD LATE TONIGHT/FRIDAY MORNING BEFORE HIGH LEVEL CLOUDS BEGIN STREAMING IN AHEAD OF THE LOW. WITH DRIER AIR MOVING IN WITH THE HIGH AS WELL...NOT ANTICIPATING MUCH IN THE FORM OF FOG DEVELOPMENT TONIGHT. HAVE MORE OF A HANDLE ON TEMPS FOR TONIGHT/TOMORROW...USING GENERALLY A BLEND OF THE MET/MAV GUIDANCE. TEMPS TONIGHT EXPECTED TO BE RIGHT AROUND NORMAL TO SLIGHTLY ABOVE. WITH MOSTLY SUNNY SKIES ON FRIDAY AND WAA...SHOULD SEE HIGHS A FEW DEGREES WARMER THAN TODAY. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... ALL NWP GUIDANCE REMAINS VERY CONSISTENT WITH A COLD FROPA ON SATURDAY. PCPN MOVES IN FROM WEST TO EAST IN THE MORNING AND EXITS IN THE AFTN WITH CLEARING QUICKLY DEVELOPING BY SATURDAY EVENING. HAVE CUT PREVIOUS FORECAST QPF IN COORDINATION WITH RIVER FORECAST CENTERS. EXPECTING AROUND 1/2 INCH WITH 3/4 INCH UP IN THE LOWER HUDSON VALLEY. NO HYDRO ISSUES EXPECTED. HIGH PRESSURE FOR SUNDAY AND MONDAY. CLOUDS START INCREASING LATE MONDAY WITH WAA. OVER-RUNNING PATTERN CONTINUES ON TUES WITH CHC POPS FOR LGT RA. WEAK AND DIFFUSE COLD FROPA PASSAGE EARLY WEDNESDAY MORNING WITH HIGH PRESSURE BUILDING IN. HAVE MADE IT DRY ON WEDNESDAY WITH TIMING OF COLD FROPA. LOWERED TEMPS AND MADE FOR NON-DIURNAL PATTERN ON SATURDAY WITH THE PCPN. BELOW NORMAL TEMPS ON SUNDAY...BUT WE QUICKLY RETURN TO NORMAL ON MONDAY AND THEN A BIT ABOVE NORMAL FOR TUESDAY AND WEDNESDAY. NO HAZARDS FORESEEN THROUGH WEDNESDAY. && .AVIATION /11Z THURSDAY THROUGH MONDAY/... LOW PRESSURE WELL E OF CAPE COD WILL REMAIN NEARLY STATIONARY... WHILE AN UPPER LEVEL LOW OVER THE AREA MOVES TO THE EAST... ALLOWING HIGH PRESSURE TO BUILD DOWN FROM NEW ENGLAND. CIGS HAVE LIFTED TO LOW-END VFR IN/NEAR COASTAL SW CT...INCLUDING KBDR/KHPN. THIS COULD POSSIBLY SPREAD SW-WARD TOWARD NYC METRO BUT THIS REMAINS UNCERTAIN...BUT EVEN IF IT DOES EXPECT TO BE SHORT-LIVED...SO TAF MENTIONS WIDESPREAD MVFR CONDS INTO THE AFTERNOON...UNTIL AT LEAST 21Z-22Z AT MOST TERMINALS...POSSIBLY ENDING AN HR OR TWO EARLIER AT KSWF/KHPN/KTEB/KEWR AS HIGH PRESSURE AND DRIER AIR BUILD SW-WARD. N-NE FLOW SHOULD INCREASE CLOSER TO 15 KT AT MOST TERMINALS AFTER DAYBREAK AS THE HIGH STARTS TO BUILD DOWN...WITH FREQUENT GUSTS JUST OVER 20 KT AT KISP/KGON/KLGA/KJFK. LESS FREQUENT GUSTS UP TO 20 KT MAY OCCUR ELSEWHERE. AS VFR CONDS RETURN LATE THIS AFTERNOON OR EARLY THU EVENING...NE FLOW WILL GRADUALLY DIMINISH TO UNDER 10 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: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT INTO THIS AFTERNOON. KLGA FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS INTO THIS AFTERNOON. BRIEF WINDOW OF OVC035 CIGS POSSIBLE EARLY THIS AM. IMPROVEMENT TO VFR LATER THIS AFTERNOON COULD OCCUR 1-2 HRS EARLIER THAN FCST. KEWR FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT THIS MORNING. IMPROVEMENT TO VFR THIS AFTERNOON COULD OCCUR 1-2 HRS EARLIER THAN FCST. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS INTO THIS AFTERNOON. BRIEF WINDOW OF OVC035 CIGS POSSIBLE EARLY THIS AM. IMPROVEMENT TO VFR LATER THIS AFTERNOON COULD OCCUR 1-2 HRS EARLIER THAN FCST. KHPN FCSTER COMMENTS: OCNL OVC035 VFR CIGS BEFORE 12Z. IMPROVEMENT TO VFR LATER THIS AFTERNOON COULD OCCUR 1-2 HRS EARLIER THAN FCST. KISP FCSTER COMMENTS: HIGH CONFIDENCE ON WINDS AND FLIGHT CAT INTO THIS AFTERNOON. .OUTLOOK FOR 06Z FRIDAY THROUGH MONDAY... .LATE TONIGHT-FRI...VFR. .FRI NIGHT...MVFR CONDS POSSIBLE LATE AT THE NYC METRO AND LOWER HUDSON VALLEY TERMINALS. .SAT...RAIN WITH IFR CONDS AND SE WINDS 15-20G25KT. COLD FROPA MID TO LATE AFTERNOON AT THE NYC METRO AND LOWER HUDSON VALLEY TERMINALS...FOLLOWED BY VFR CONDS AND W WIND G20KT. .SAT NIGHT...RAIN WITH IFR CONDS EARLY AT THE CT/LONG ISLAND TERMINALS...THEN COLD FROPA WITH IMPROVEMENT TO VFR. POST-FRONTAL W WINDS G25KT. .SUNDAY...VFR. W WINDS G20KT. .MON...VFR. && .MARINE... MINIMAL SCA REMAINS IN EFFECT FOR ALL THE WATERS LESS THE GREAT SOUTH BAY...NY HARBOR AND THE WESTERN SOUND AS NE FLOW INCREASES BETWEEN THE LOW OFFSHORE AND THE HIGH DIGGING DOWN FROM THE NORTH. GUSTS BETWEEN 23 TO 28 KT EXPECTED DURING THE DAY TODAY...THEN DIMINISHING TONIGHT AS THE PRESSURE GRADIENT WEAKENS WITH HIGH BUILDING FURTHER OVER THE WATERS. SEAS BUILD TODAY WITH THE STRENGTHENING FLOW...WITH 5-9 FT POSSIBLE ON THE OCEAN WATERS. OCNL GUSTS UP TO 25 KT WILL BE POSSIBLE THIS EVENING/EARLY OVERNIGHT FOR THE BAYS AND LONG ISLAND SOUND. THOUGH CONFIDENCE IS NOT ENOUGH TO EXTEND THE SCA AT THIS TIME OVER THOSE WATERS. STILL EXPECTING GUSTS TO 25 KT AND SEAS ABOVE 5 FT ON THE OCEAN...AND IN FACT EXPECTING THE 5 FT SEAS TO CONTINUE SO EXTENDED THE SCA OVER THE OCEAN FOR FRIDAY. ON THE OCEAN...SCA CONDS CAN BE EXPECTED THRU NEXT WED...WITH PERHAPS A BRIEF RESPITE FOR PORTIONS OF MON. ELSEWHERE...25KT WINDS POSSIBLE SAT-SUN BOTH AHEAD OF AND BEHIND A CDFNT. OTHERWISE THEY WILL GENERALLY BE IN THE 10-20KT RANGE. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH FRI EVENING. EXPECTING AROUND 1/2 INCH WITH 3/4 UP IN THE LOWER HUDSON VALLEY DURING THE DAY ON SATURDAY. LIGHT RAIN IS POSSIBLE FOR TUESDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330- 340. && $$ SYNOPSIS...SEARS/TONGUE NEAR TERM...SEARS/TONGUE SHORT TERM...SEARS LONG TERM...TONGUE AVIATION...GOODMAN MARINE...SEARS/TONGUE HYDROLOGY...SEARS/TONGUE
AREA FORECAST DISCUSSION
NWS ALBANY NY
717 AM EDT THU OCT 2 2014 .SYNOPSIS... CLOUDS WILL EVENTUALLY BREAK FOR SUNSHINE TODAY AS AN UPPER LEVEL STORM SOUTH OF NEW ENGLAND CONTINUES TO MOVE EASTWARD AND AWAY FROM THE REGION. DRY AND WARM CONDITIONS ARE EXPECTED ON FRIDAY...BEFORE A COLD FRONT BRINGS GUSTY RAIN SHOWERS AND COOLER TEMPERATURES TO THE REGION FOR THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 632 AM EDT...AN UPPER LEVEL LOW IS SITUATED JUST SOUTHEAST OF EASTERN NEW ENGLAND. THIS SYSTEM IS MOVING AWAY...BUT BEFORE IT DOES...IT IS PULLING MOISTURE OFF THE ATLANTIC OCEAN AND PRODUCING SHOWERS ACROSS PARTS OF MASSACHUSETTS AND CONNECTICUT. WITH THESE SHOWERS WRAPPING AROUND THE UPPER LEVEL LOW WITHIN THE BROAD EASTERLY FLOW ALOFT...THEY ARE TRACKING INTO PARTS OF SRN VT...THE BERKSHIRES...AND LITCHFIELD HILLS THIS MORNING. WHILE SHOWERS HAVE MAINLY DIMINISHED OVER OUR AREA...WE CANNOT RULE OUT A LIGHT RAIN SHOWER OR SPRINKLE ACROSS WESTERN NEW ENGLAND THROUGH THE MID MORNING HOURS. THE LATEST 08Z 3KM HRRR SHOWS ANY ACTIVITY AFTER THIS TIME REMAINING WELL EAST OF OUR AREA. IN ADDITION TO THE RAIN SHOWERS IS PLENTY OF LOW CLOUDS /STRATUS/ AND SOME PATCHES OF FOG. WITH A LOW LEVEL INVERSION IN PLACE TODAY...IT WILL TAKE A WHILE FOR THIS LOW LEVEL MOISTURE TO BECOME MIXED OUT. AS A RESULT...WE CAN EXPECT MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY...WITH CLOUDS EVENTUALLY BREAKING FOR INCREASING AMOUNTS OF SUN DURING THE AFTN. THE EXCEPTION WILL BE ACROSS THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS...WHERE THE CLOUDS CURRENTLY AREN/T AS THICK...AND MORE SUN CAN BE EXPECTED THIS MORNING. MAX TEMPS TODAY WILL RANGE FROM THE LOW 60S TO LOW 70S...WITH THE WARMEST ACROSS WESTERN AREAS. TEMPS IN THE CAPITAL REGION/HUDSON VALLEY LOOK TO TOP OUT IN THE UPPER 60S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... A BRIEF AREA OF UPPER LEVEL RIDGING WILL BUILD INTO THE AREA FOR TONIGHT INTO FRIDAY. THIS WILL ALLOW FOR CONTINUED CLEARING SKIES OVERNIGHT...ALTHOUGH SOME PATCHY FOG WILL DEVELOP THANKS TO THE GOOD RADIATIONAL COOLING CONDITIONS. MIN TEMPS TONIGHT WILL MAINLY BE IN THE 40S TO NEAR 50. PARTLY TO MOSTLY SUNNY SKIES ARE EXPECTED ON FRIDAY...WITH THE MOST CLOUDS ACROSS THE ADIRONDACKS. WITH 850 HPA TEMPS AROUND 10 TO 11 DEGREES C...ABOVE NORMAL TEMPS CAN BE EXPECTED...WITH HIGHS IN THE MID 60S TO MID 70S ACROSS THE AREA. A STRONG COLD FRONT WILL BE MOVING TOWARDS THE AREA FOR FRIDAY NIGHT INTO SATURDAY. MOST OF THE FRIDAY NIGHT SHOULD BE DRY...ALTHOUGH WESTERN AREAS WILL START TO SEE SOME SHOWERS BY LATER IN THE NIGHT. MIN TEMPS FRI NIGHT WILL BE IN THE 50S. THIS FRONT WILL BE ACCOMPANIED BY A DEEPENING TROUGH THAT WILL TAKE ON A NEGATIVE TILT FOR SATURDAY. AHEAD OF THIS FRONT...A STRONG LOW LEVEL JET OF 50 KNOTS /ABOUT 3 TO 5 STD ABOVE NORMAL ACCORDING TO THE 850 HPA V WINDS ON THE 00Z GEFS/ WILL BE IN PLACE...ALLOWING FOR PLENTY OF MOISTURE TO WORK ITS WAY INTO THE REGION. PWATS WILL EXCEED 1.50 INCHES OVER MUCH OF THE AREA...WHICH IS ABOUT 2-3 STD ABOVE NORMAL FOR THIS TIME OF YEAR. AS A RESULT...A LINE OF MODERATE TO HEAVY RAIN SHOWERS WILL PRECEDE AND ACCOMPANY THE FRONTAL PASSAGE. A WEAK WAVE OF LOW PRESSURE MAY DEVELOP ON THE FRONT AS WELL...WHICH MAY SLOW DOWN THE FRONT/S PROGRESS AS WELL...ALLOWING FOR A PROLONGED PERIOD OF RAINFALL. THIS SHOULD ALLOW FOR ABOUT A HALF INCH TO ONE INCH OF RAIN ACROSS THE ENTIRE REGION FOR SATURDAY. SOME GUSTY WINDS WILL ACCOMPANY THE SHOWERS AS WELL DUE TO THE STRONG DYNAMICS IN PLACE. WE WON/T MENTION THUNDER AT THIS TIME...AS INSTABILITY LOOKS TO BE LACKING. WITH THE CLOUDS/SHOWERS...IT WILL BE COOLER THAN FRIDAY...WITH HIGHS IN THE UPPER 50S TO LOW 60S. THE FRONT SHOULD BE THROUGH MOST OF THE AREA BY THE EVENING HOURS...ALLOWING FOR COOLER AND DRIER AIR TO WORK INTO THE REGION. WITH MUCH COOLER AIR ALOFT...SOME ADDITIONAL CYCLONIC FLOW/LAKE ENHANCED RAIN SHOWERS WILL BE POSSIBLE DOWNWIND OF LAKE ONTARIO FOR SAT NIGHT. OTHERWISE...SHOWERS WILL BE ENDING...WITH DECREASING CLOUDS THROUGH THE OVERNIGHT HOURS. MIN TEMPS WILL RANGE FROM THE MID 30S TO MID 40S. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... A MEAN UPPER TROUGH WILL CONTINUE OVER EASTERN NORTH AMERICA WITH THE AXIS WEST OF OUR REGION...PUTTING OUR REGION IN THE WEST TO SOUTHWEST UPPER FLOW PORTION OF THE MEAN UPPER TROUGH. ANY LINGERING SHOWERS FROM THE EXITING COLD FRONT WILL EXIT SUNDAY MORNING...BUT RAPIDLY COOLING BOUNDARY LAYER TEMPERATURES AND LOW LEVEL WINDS OFF THE GREAT LAKES...SOME SCATTERED SHOWERS COULD EXTEND FROM THE LAKES INTO THE SOUTHERN ADIRONDACKS SUNDAY AND SUNDAY NIGHT. HIGHS SUNDAY IN THE 50S TO LOWER 60S. SOME DISAGREEMENTS IN GUIDANCE/ENSEMBLES AS TO ANOTHER UPPER IMPULSE...BASED MORE IN THE NORTHERN STREAM...POSSIBLY TRACKING AROUND THE SOUTHERN PERIPHERY OF THE UPPER TROUGH AND THROUGH OUR REGION LATER MONDAY THROUGH TUESDAY...WITH MORE SCATTERED SHOWERS AND SOME BOUNDARY LAYER WARMING AS THE UPPER TROUGH AXIS RETROGRADES A LITTLE. THERE IS A LOOSE CONSENSUS IN SOME WARMING AND RETROGRADING OF THE UPPER TROUGH...THE DISAGREEMENTS ARE WHETHER WE GET LITTLE TO NO COVERAGE OF SHOWERS OR BETTER COVERAGE OF SHOWERS...DEPENDING ON THE PRESENCE OR NON PRESENCE OF WELL DEFINED UPPER DYNAMICS. FOR NOW...INDICATING JUST CHANCES FOR SHOWERS...BUT THE DETAILS HOW MUCH POTENTIAL FOR RAIN TUESDAY WILL GET CLEARER AS WE GET NEARER TO NEXT WEEK. HIGHS MONDAY IN THE UPPER 50S TO MID 60S. HIGHS TUESDAY IN THE UPPER 60S TO AROUND 70...WITH LOWER 60S HIGHER ELEVATIONS. THERE ARE ALSO CONFLICTS IN GUIDANCE/ENSEMBLES AS TO WHETHER ANOTHER UPPER IMPULSE AND THE LEADING EDGE OF COOLER AIR ARRIVES WEDNESDAY. THE RAPID UPPER FLOW PATTERN IS DIFFICULT FOR LONG RANGE GUIDANCE TO RESOLVE. SO...JUST INDICATING SHOWERS EXITING TUESDAY NIGHT AND WEDNESDAY WITH HIGHS WEDNESDAY IN THE MID TO UPPER 60S...SOME UPPER 50S HIGHER ELEVATIONS. && .AVIATION /11Z THURSDAY THROUGH MONDAY/... SYSTEM IS STILL SLOWLY EXITING BUT CLOUD LAYER AROUND 2500 FEET STILL LINGERING AS MOISTURE IS BEING TRANSPORTED FROM THE COAST INLAND. THE NORTHERN AND WESTERN EDGE OF THE RAIN SHIELD IS NOW INTO CENTRAL MA...SO THE VCSH FOR KPSF SHOULD CONTINUE ONLY THROUGH ABOUT 14Z. CLEARING IS STILL SEEN IN NORTHERN AND CENTRAL/WESTERN NY...BUT AGAIN THE MOIST FLOW FROM THE COAST CIRCULATING AROUND THE COASTAL SYSTEM WILL RESULT IN A SLOW ADVANCE TO THE CLEARING. THE MVFR CEILINGS SHOULD PERSIST UNTIL AROUND 18Z-22Z...THEN VFR CONDITIONS SHOULD PREVAIL AFTER THAT THROUGH THE NIGHT. WITH MAINLY CLEAR SKY TONIGHT...WITH SOME INTERVALS OF CLOUDS...ADDED SOME MVFR FOG TO KGFL AND KPSF WHERE CLEARING WOULD PROMOTE THE BEST CHANCES FOR FOG. LIGHT TO CALM WINDS THROUGH DAYBREAK WITH A LIGHT N-NE FLOW AT LESS THAN 6 KT SHIFTING TO E-SE AS THE DAY PROGRESSES THURSDAY...TRENDING BACK TO VARIABLE/CALM DURING THE EVENING AND THROUGH THE NIGHT. OUTLOOK... FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY: HIGH OPERATIONAL IMPACT. DEFINITE SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY THROUGH MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ALONG WITH SOME AREAS OF MORNING FOG...WIDESPREAD CLOUD COVER IS EXPECTED THROUGH AT LEAST THIS MORNING. THERE MAY BE A FEW SPRINKLES EARLY THIS MORNING ACROSS FAR EASTERN AREAS AS WELL. RH VALUES WILL DROP TO 50 TO 60 PERCENT THIS AFTERNOON WITH LIGHT EASTERLY WINDS. RH VALUES WILL RECOVER TO 90 TO 100 PERCENT TONIGHT WITH FOG AND DEW FORMATION AND NEARLY CALM WINDS. AFTER MORNING FOG BURNS OFF TOMORROW...MOSTLY SUNNY SKIES ARE EXPECTED THROUGH MUCH OF THE DAY FRIDAY WITH RH VALUES DROPPING TO 45 TO 50 PERCENT IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL BE 5 TO 10 MPH ON FRIDAY. A WIDESPREAD WETTING RAINFALL IS EXPECTED ON SATURDAY. && .HYDROLOGY... A DEPARTING UPPER LEVEL LOW WILL ALLOW FOR A FEW LIGHT RAIN SHOWERS OR SPRINKLES EARLY THIS MORNING ACROSS NEW ENGLAND. OTHERWISE...DRY WEATHER IS ANTICIPATED FOR TODAY THROUGH TOMORROW EVENING. WITH A COLD FRONT CROSSING THE REGION...A WIDESPREAD RAINFALL IS EXPECTED BETWEEN LATE FRIDAY NIGHT AND SATURDAY. MOST AREAS WILL SEE BETWEEN ONE HALF INCH AND ONE INCH OF RAINFALL. ASIDE FROM SOME PUDDLES ON ROADWAYS...THIS RAINFALL WILL NOT CAUSE ANY HYDROLOGIC ISSUES...AND WILL BE BENEFICIAL TO THE REGION. MAINLY DRY...BUT MUCH COOLER....WEATHER IS EXPECTED FOR SUNDAY INTO MONDAY. OVERALL...AREA RIVERS AND STREAMS LOOK TO MAINLY HOLD STEADY OR ONLY SLIGHTLY RISE THROUGH THE WEEKEND. 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...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...11/NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS ALBANY NY
632 AM EDT THU OCT 2 2014 .SYNOPSIS... CLOUDS WILL EVENTUALLY BREAK FOR SUNSHINE TODAY AS AN UPPER LEVEL STORM SOUTH OF NEW ENGLAND CONTINUES TO MOVE EASTWARD AND AWAY FROM THE REGION. DRY AND WARM CONDITIONS ARE EXPECTED ON FRIDAY...BEFORE A COLD FRONT BRINGS GUSTY RAIN SHOWERS AND COOLER TEMPERATURES TO THE REGION FOR THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 632 AM EDT...AN UPPER LEVEL LOW IS SITUATED JUST SOUTHEAST OF EASTERN NEW ENGLAND. THIS SYSTEM IS MOVING AWAY...BUT BEFORE IT DOES...IT IS PULLING MOISTURE OFF THE ATLANTIC OCEAN AND PRODUCING SHOWERS ACROSS PARTS OF MASSACHUSETTS AND CONNECTICUT. WITH THESE SHOWERS WRAPPING AROUND THE UPPER LEVEL LOW WITHIN THE BROAD EASTERLY FLOW ALOFT...THEY ARE TRACKING INTO PARTS OF SRN VT...THE BERKSHIRES...AND LITCHFIELD HILLS THIS MORNING. WHILE SHOWERS HAVE MAINLY DIMINISHED OVER OUR AREA...WE CANNOT RULE OUT A LIGHT RAIN SHOWER OR SPRINKLE ACROSS WESTERN NEW ENGLAND THROUGH THE MID MORNING HOURS. THE LATEST 08Z 3KM HRRR SHOWS ANY ACTIVITY AFTER THIS TIME REMAINING WELL EAST OF OUR AREA. IN ADDITION TO THE RAIN SHOWERS IS PLENTY OF LOW CLOUDS /STRATUS/ AND SOME PATCHES OF FOG. WITH A LOW LEVEL INVERSION IN PLACE TODAY...IT WILL TAKE A WHILE FOR THIS LOW LEVEL MOISTURE TO BECOME MIXED OUT. AS A RESULT...WE CAN EXPECT MOSTLY CLOUDY SKIES THROUGH MUCH OF THE DAY...WITH CLOUDS EVENTUALLY BREAKING FOR INCREASING AMOUNTS OF SUN DURING THE AFTN. THE EXCEPTION WILL BE ACROSS THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS...WHERE THE CLOUDS CURRENTLY AREN/T AS THICK...AND MORE SUN CAN BE EXPECTED THIS MORNING. MAX TEMPS TODAY WILL RANGE FROM THE LOW 60S TO LOW 70S...WITH THE WARMEST ACROSS WESTERN AREAS. TEMPS IN THE CAPITAL REGION/HUDSON VALLEY LOOK TO TOP OUT IN THE UPPER 60S. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... A BRIEF AREA OF UPPER LEVEL RIDGING WILL BUILD INTO THE AREA FOR TONIGHT INTO FRIDAY. THIS WILL ALLOW FOR CONTINUED CLEARING SKIES OVERNIGHT...ALTHOUGH SOME PATCHY FOG WILL DEVELOP THANKS TO THE GOOD RADIATIONAL COOLING CONDITIONS. MIN TEMPS TONIGHT WILL MAINLY BE IN THE 40S TO NEAR 50. PARTLY TO MOSTLY SUNNY SKIES ARE EXPECTED ON FRIDAY...WITH THE MOST CLOUDS ACROSS THE ADIRONDACKS. WITH 850 HPA TEMPS AROUND 10 TO 11 DEGREES C...ABOVE NORMAL TEMPS CAN BE EXPECTED...WITH HIGHS IN THE MID 60S TO MID 70S ACROSS THE AREA. A STRONG COLD FRONT WILL BE MOVING TOWARDS THE AREA FOR FRIDAY NIGHT INTO SATURDAY. MOST OF THE FRIDAY NIGHT SHOULD BE DRY...ALTHOUGH WESTERN AREAS WILL START TO SEE SOME SHOWERS BY LATER IN THE NIGHT. MIN TEMPS FRI NIGHT WILL BE IN THE 50S. THIS FRONT WILL BE ACCOMPANIED BY A DEEPENING TROUGH THAT WILL TAKE ON A NEGATIVE TILT FOR SATURDAY. AHEAD OF THIS FRONT...A STRONG LOW LEVEL JET OF 50 KNOTS /ABOUT 3 TO 5 STD ABOVE NORMAL ACCORDING TO THE 850 HPA V WINDS ON THE 00Z GEFS/ WILL BE IN PLACE...ALLOWING FOR PLENTY OF MOISTURE TO WORK ITS WAY INTO THE REGION. PWATS WILL EXCEED 1.50 INCHES OVER MUCH OF THE AREA...WHICH IS ABOUT 2-3 STD ABOVE NORMAL FOR THIS TIME OF YEAR. AS A RESULT...A LINE OF MODERATE TO HEAVY RAIN SHOWERS WILL PRECEDE AND ACCOMPANY THE FRONTAL PASSAGE. A WEAK WAVE OF LOW PRESSURE MAY DEVELOP ON THE FRONT AS WELL...WHICH MAY SLOW DOWN THE FRONT/S PROGRESS AS WELL...ALLOWING FOR A PROLONGED PERIOD OF RAINFALL. THIS SHOULD ALLOW FOR ABOUT A HALF INCH TO ONE INCH OF RAIN ACROSS THE ENTIRE REGION FOR SATURDAY. SOME GUSTY WINDS WILL ACCOMPANY THE SHOWERS AS WELL DUE TO THE STRONG DYNAMICS IN PLACE. WE WON/T MENTION THUNDER AT THIS TIME...AS INSTABILITY LOOKS TO BE LACKING. WITH THE CLOUDS/SHOWERS...IT WILL BE COOLER THAN FRIDAY...WITH HIGHS IN THE UPPER 50S TO LOW 60S. THE FRONT SHOULD BE THROUGH MOST OF THE AREA BY THE EVENING HOURS...ALLOWING FOR COOLER AND DRIER AIR TO WORK INTO THE REGION. WITH MUCH COOLER AIR ALOFT...SOME ADDITIONAL CYCLONIC FLOW/LAKE ENHANCED RAIN SHOWERS WILL BE POSSIBLE DOWNWIND OF LAKE ONTARIO FOR SAT NIGHT. OTHERWISE...SHOWERS WILL BE ENDING...WITH DECREASING CLOUDS THROUGH THE OVERNIGHT HOURS. MIN TEMPS WILL RANGE FROM THE MID 30S TO MID 40S. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... A MEAN UPPER TROUGH WILL CONTINUE OVER EASTERN NORTH AMERICA WITH THE AXIS WEST OF OUR REGION...PUTTING OUR REGION IN THE WEST TO SOUTHWEST UPPER FLOW PORTION OF THE MEAN UPPER TROUGH. ANY LINGERING SHOWERS FROM THE EXITING COLD FRONT WILL EXIT SUNDAY MORNING...BUT RAPIDLY COOLING BOUNDARY LAYER TEMPERATURES AND LOW LEVEL WINDS OFF THE GREAT LAKES...SOME SCATTERED SHOWERS COULD EXTEND FROM THE LAKES INTO THE SOUTHERN ADIRONDACKS SUNDAY AND SUNDAY NIGHT. HIGHS SUNDAY IN THE 50S TO LOWER 60S. SOME DISAGREEMENTS IN GUIDANCE/ENSEMBLES AS TO ANOTHER UPPER IMPULSE...BASED MORE IN THE NORTHERN STREAM...POSSIBLY TRACKING AROUND THE SOUTHERN PERIPHERY OF THE UPPER TROUGH AND THROUGH OUR REGION LATER MONDAY THROUGH TUESDAY...WITH MORE SCATTERED SHOWERS AND SOME BOUNDARY LAYER WARMING AS THE UPPER TROUGH AXIS RETROGRADES A LITTLE. THERE IS A LOOSE CONSENSUS IN SOME WARMING AND RETROGRADING OF THE UPPER TROUGH...THE DISAGREEMENTS ARE WHETHER WE GET LITTLE TO NO COVERAGE OF SHOWERS OR BETTER COVERAGE OF SHOWERS...DEPENDING ON THE PRESENCE OR NON PRESENCE OF WELL DEFINED UPPER DYNAMICS. FOR NOW...INDICATING JUST CHANCES FOR SHOWERS...BUT THE DETAILS HOW MUCH POTENTIAL FOR RAIN TUESDAY WILL GET CLEARER AS WE GET NEARER TO NEXT WEEK. HIGHS MONDAY IN THE UPPER 50S TO MID 60S. HIGHS TUESDAY IN THE UPPER 60S TO AROUND 70...WITH LOWER 60S HIGHER ELEVATIONS. THERE ARE ALSO CONFLICTS IN GUIDANCE/ENSEMBLES AS TO WHETHER ANOTHER UPPER IMPULSE AND THE LEADING EDGE OF COOLER AIR ARRIVES WEDNESDAY. THE RAPID UPPER FLOW PATTERN IS DIFFICULT FOR LONG RANGE GUIDANCE TO RESOLVE. SO...JUST INDICATING SHOWERS EXITING TUESDAY NIGHT AND WEDNESDAY WITH HIGHS WEDNESDAY IN THE MID TO UPPER 60S...SOME UPPER 50S HIGHER ELEVATIONS. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... WITH A SURFACE LOW PASSING WELL TO OUR SOUTH AND AN UPPER LEVEL LEVEL LOW EXITING THE REGION HAVE LOTS OF CLOUDS AND LOW LEVEL MOISTURE IN PLACE. SOME SHOWERS AND DRIZZLE WILL LINGER THROUGH THE EARLY MORNING HOURS AT KALB AND KPSF WITH CHANCES DECREASING TOWARD DAYBREAK. CLOUDS HEIGHTS WILL BE JUST ABOVE 3000 FEET AT KGFL BUT TRENDING DOWNWARD TO MVFR BETWEEN 06Z-12Z AND REMAIN MVFR THROUGH ABOUT 18Z. CEILINGS WILL VARY BETWEEN IFR AND VFR PERIODICALLY AT KALB THROUGH ABOUT 12Z. CEILINGS IN THE MVFR RANGE AT KPOU AND KPSF SHOULD REMAIN IN THE MVFR RANGE THROUGH ABOUT 20Z-22Z. VISIBILITIES SHOULD BE MOSTLY VFR WITH ANY RAIN BEING VERY LIGHT THROUGH THE EARLY MORNING HOURS. SOME MVFR VISIBILITIES ARE LIKELY AT KALB AND KGFL AFTER 10Z...ESPECIALLY IF THERE IS SOME PARTIAL CLEARING...WHICH IS NOT TOO FAR WEST OF THE TAF SITES CURRENTLY. SOME INTERVALS OF MVFR VISIBILITIES ARE POSSIBLE AT KPSF AND KPOU...KPSF WITH POSSIBLE LIGHT RAIN AND KPOU WITH SOME POSSIBLE PARTIAL CLEARING. IT SHOULD BE MENTIONED THAT CURRENT TRENDS IN SATELLITE AND RADAR SUGGEST ANY CLEARING WILL TAKE QUITE SOME TIME TO SPREAD EAST...EVEN THOUGH IT IS INTO THE SOUTHERN ADIRONDACKS...AND CENTRAL/WESTERN MOHAWK VALLEY. ONCE THE SYSTEM EXITS...CEILINGS SHOULD LIFT ABOVE 3000 FEET AFTER 18Z-22Z AND REMAIN VFR THROUGH THIS EVENING. HOWEVER...IFR CONDITIONS ARE EXPECTED AT KPSF FOR A GOOD CHUNK OF THE OVERNIGHT. GRADUALLY IMPROVEMENT ON THURSDAY WITH VFR DEVELOPING DURING THE AFTERNOON AS THE UPPER LEVEL MOVES OFF TO THE EAST AND RIDGING BUILDS IN. LIGHT TO CALM WINDS THROUGH DAYBREAK WITH A LIGHT N-NE FLOW AT LESS THAN 6 KT SHIFTING TO E-SE AS THE DAY PROGRESSES THURSDAY...TRENDING BACK TO VARIABLE/CALM DURING THE EVENING. OUTLOOK... FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SATURDAY: HIGH OPERATIONAL IMPACT. DEFINITE SHRA. SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. SUNDAY THROUGH MONDAY: NO OPERATIONAL IMPACT. NO SIG WX. && .FIRE WEATHER... ALONG WITH SOME AREAS OF MORNING FOG...WIDESPREAD CLOUD COVER IS EXPECTED THROUGH AT LEAST THIS MORNING. THERE MAY BE A FEW SPRINKLES EARLY THIS MORNING ACROSS FAR EASTERN AREAS AS WELL. RH VALUES WILL DROP TO 50 TO 60 PERCENT THIS AFTERNOON WITH LIGHT EASTERLY WINDS. RH VALUES WILL RECOVER TO 90 TO 100 PERCENT TONIGHT WITH FOG AND DEW FORMATION AND NEARLY CALM WINDS. AFTER MORNING FOG BURNS OFF TOMORROW...MOSTLY SUNNY SKIES ARE EXPECTED THROUGH MUCH OF THE DAY FRIDAY WITH RH VALUES DROPPING TO 45 TO 50 PERCENT IN THE AFTERNOON. SOUTH TO SOUTHEAST WINDS WILL BE 5 TO 10 MPH ON FRIDAY. A WIDESPREAD WETTING RAINFALL IS EXPECTED ON SATURDAY. && .HYDROLOGY... A DEPARTING UPPER LEVEL LOW WILL ALLOW FOR A FEW LIGHT RAIN SHOWERS OR SPRINKLES EARLY THIS MORNING ACROSS NEW ENGLAND. OTHERWISE...DRY WEATHER IS ANTICIPATED FOR TODAY THROUGH TOMORROW EVENING. WITH A COLD FRONT CROSSING THE REGION...A WIDESPREAD RAINFALL IS EXPECTED BETWEEN LATE FRIDAY NIGHT AND SATURDAY. MOST AREAS WILL SEE BETWEEN ONE HALF INCH AND ONE INCH OF RAINFALL. ASIDE FROM SOME PUDDLES ON ROADWAYS...THIS RAINFALL WILL NOT CAUSE ANY HYDROLOGIC ISSUES...AND WILL BE BENEFICIAL TO THE REGION. MAINLY DRY...BUT MUCH COOLER....WEATHER IS EXPECTED FOR SUNDAY INTO MONDAY. OVERALL...AREA RIVERS AND STREAMS LOOK TO MAINLY HOLD STEADY OR ONLY SLIGHTLY RISE THROUGH THE WEEKEND. 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...FRUGIS NEAR TERM...FRUGIS SHORT TERM...FRUGIS LONG TERM...NAS AVIATION...NAS FIRE WEATHER...FRUGIS HYDROLOGY...FRUGIS
AREA FORECAST DISCUSSION
NWS MIAMI FL
1035 AM EDT THU OCT 2 2014 .UPDATE... NO MAJOR UPDATES ARE ANTICIPATED THIS MORNING AS THE PREVIOUS FORECAST REMAINS ON TRACK. THE MORNING SURFACE ANALYSIS SHOWED A STALLED FRONTAL BOUNDARY EXTENDING WESTWARD ACROSS CENTRAL FLORIDA WITH MAINLY LIGHT WNW FLOW CONTINUING ACROSS SOUTH FLORIDA. THE LOW-LEVEL FLOW UP TO 700MB FROM THE MORNING UPPER AIR SOUNDING IN MIAMI WAS SLIGHTLY WEAKER THAN THE PAST FEW DAYS. THIS LOW-LEVEL FLOW COMBINED WITH DAYTIME HEATING SHOULD ALLOW THE EAST COAST SEA BREEZE TO SETUP THROUGH THE AFTERNOON HOURS AND BECOME MORE ESTABLISHED. THE LATEST HRRR MODEL RUN REFLECTS THIS PATTERN AND GENERALLY INDICATES THE BEST SHOWER AND THUNDERSTORM COVERAGE THIS AFTERNOON SETTING UP AND FOCUSING OVER BROWARD AND MIAMI-DADE COUNTIES. WEAK MID-LEVEL LAPSE RATES ALONG WITH FAIRLY WARM 500MB TEMPERATURES AND RISING UPPER HEIGHTS SHOULD KEEP THE THREAT OF STRONG TO SEVERE THUNDERSTORMS LOW TODAY. THE MAIN IMPACTS FROM THE STORMS THAT DO MANAGE TO DEVELOP WILL BE LIGHTNING AND 35 TO 45 MPH WIND GUSTS. 85 && .PREV DISCUSSION... /ISSUED 802 AM EDT THU OCT 2 2014/ AVIATION... REGIONAL OBSERVATIONS INDICATE THERE IS ISOLATED AREAS WITH LOW STRATUS AND/OR MIST ACROSS SOUTH FLORIDA...MAINLY IN THE VICINITY OF THE LAKE WITH CURRENT METAR OBS FROM KPBI INDICATING BRIEF PERIODS OF IFR CEILINGS POSSIBLE EARLY THIS MORNING. TERMINAL KTMB MAY HAVE VERY BRIEF PERIODS OF IFR VISIBILITY EARLY THIS MORNING. OTHERWISE...CHALLENGING WIND FORECAST. WEAK WESTERLY WINDS PREVAIL ACROSS THE REGION AND FORECAST TO BECOMING NORTHWESTERLY LATER THIS MORNING. AFTER 18Z THE WEST AND EAST COAST SEA BREEZES ARE EXPECTED TO FORM...BUT FOR TERMINALS KTMB AND KOPF WINDS COULD STAY LIGHT NORTHWESTERLY. LINGERING TROPICAL MOISTURE COULD FAVOR SHOWERS/THUNDERSTORMS THIS AFTERNOON...WITH WESTERLY WINDS FAVORING CONVECTION IN THE EASTERN HALF OF THE PENINSULA. ALL EAST COAST TERMINALS ASSIGNED VCTS IN THE 18Z TO 21Z TIME FRAME. 60 PREV DISCUSSION... /ISSUED 328 AM EDT THU OCT 2 2014/ .TYPICAL AFTERNOON SCATTERED THUNDERSTORMS NEXT FEW DAYS... .FIRST COLD FRONT OF FALL SEASON ARRIVES SATURDAY NIGHT... DISCUSSION...SURFACE RIDGE WILL REMAIN OVER THE FLORIDA STRAITS THROUGH FRIDAY, MAINTAINING A WESTERLY WIND FLOW. THIS WILL FOCUS SCATTERED THUNDERSTORMS OVER THE INTERIOR AND EAST COAST METRO AS AN ATLANTIC SEA BREEZE DEVELOPS DURING THE AFTERNOON. SOME DRIER AIR IN THE MID LEVELS IS EXPECTED TO KEEP CONVECTION SCATTERED THIS AFTERNOON AS WELL AS ON FRIDAY. THE MAIN IMPACTS FROM THE TSTORMS WILL BE LIGHTNING STRIKES AND BRIEF HEAVY RAINS. GFS AND ECMWF CONTINUE TO SHOW AN AMPLIFIED LONGWAVE TROUGH ACROSS THE EASTERN U.S. THIS WEEKEND, SENDING THE FIRST COLD FRONT OF THE SEASON ACROSS SOUTH FLORIDA SATURDAY NIGHT. SCATTERED CONVECTION IS EXPECTED AHEAD OF THE FRONT, BUT FORCING WILL BE TO THE NORTH SO ONLY ORDINARY STORMS ARE ONLY EXPECTED. THE BIG STORY WILL BE THE DROP IN DEWPOINTS AND A SLIGHT LOWERING OF TEMPERATURES TO MAKE A VERY NOTICEABLE CHANGE IN AIRMASS ACROSS SOUTH FLORIDA AFTER THE LONG STEAMY TIMES SINCE MAY. GUIDANCE TEMPS/POPS WERE NOT SIGNIFICANTLY CHANGED FROM THIS TIME YESTERDAY SO NO APPRECIABLE CHANGES ARE NOTED IN THE EXTENDED FORECAST. DRYING BEHIND THE FRONT WILL OCCUR SUN-MON, BUT MOISTURE LOOKS TO RETURN ON A RETURN FLOW BY TUE WITH INCREASING HUMIDITY AND A RETURN TO SCATTERED TSTORMS THEN. /GREGORIA MARINE...LIGHT WINDS AND LOW SEAS WILL CONTINUE BUT WINDS WILL PICK UP IN ASSOCIATION WITH THE FIRST COLD FRONT OF THE FALL SEASON EXPECTED TO MOVE ACROSS THE LOCAL WATERS SATURDAY NIGHT. AS WINDS TURN N THEN NE, SEAS WILL BUILD ESPECIALLY OFF THE PALM BEACH COAST BUT NWPS CURRENTLY KEEPS SEAS BELOW HAZARDOUS LEVELS, OR 7 FT. /GREGORIA && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 90 74 89 76 / 40 20 40 20 FORT LAUDERDALE 90 78 90 78 / 50 20 40 20 MIAMI 91 77 90 78 / 50 20 50 20 NAPLES 90 75 90 76 / 20 10 20 20 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...52/PS LONG TERM....57/DG
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
945 AM EDT THU OCT 2 2014 .DISCUSSION... ...TURNING NOTICEABLY DRIER AND COOLER THIS WEEKEND WITH UNFAVORABLE BOATING CONDITIONS... CURRENT-TODAY...WEAK SURFACE BOUNDARY IS STILL EVIDENT IN THE SURFACE ANALYSIS WITH EAST WINDS AT 41009 & 41010 WHILE GRAND BAHAMA HAD WEST WINDS. THERE WAS LITTLE/NO AIR MASS DEFINITION THOUGH AS ONSHORE FLOW WAS KEEPING DEW POINTS IN THE LOW/MID 70S NORTH OF THE BOUNDARY. MORNING SOUNDINGS ACROSS THE PENINSULA SHOWED PRECIPITABLE WATER 1.6 TO 1.8 INCHES. THE CAPE SOUNDING DID HAVE 1.95 BUT THAT WAS NEAR AN ATLANTIC CONVERGENCE LINE WHERE SOME SHOWERS HAVE BEEN OCCURRING ON AND OFF. THE TAMPA SOUNDING HAS AN INVERSION TO OVERCOME AROUND 750MB AND 500 MB TEMPS ARE MINUS 6. THE LOCAL WRF MODEL AND HRRR INDICATE CONVECTION INITIATING INLAND DURING THE AFTERNOON ALONG THE EAST COAST SEA BREEZE BOUNDARY. MORNING 0-6KM MEAN WINDS ARE NORTHWEST BUT BOTH MODELS DO NOT SHOW PUSHBACK TO THE COAST...SO THIS INDICATES THAT THE MODELS ARE NOT GENERATING VERY DEEP CONVECTION. THIS LOOKS REASONABLE GIVEN THE MORNING SOUNDING PARAMETERS AND EXPECT PRECIP TO BE MOSTLY SHOWERS WITH A FEW LIGHTNING STORMS INLAND. LITTLE CHANGE IS ANTICIPATED TO THE CURRENT FORECAST. && .AVIATION... PATCH OF STRATUS/FOG KVRB-KFPR WILL BE DISSIPATING SOON. HIGH AMOUNTS OF LOW LEVEL MOISTURE WILL PROBABLY LEAD TO SOME MVFR CEILINGS AS CUMULUS START FORMING THIS MORNING. EXPECT IFR CHANCES IN AFTERNOON SHOWERS OR STORMS TO BE LIMITED TO THE INTERIOR TERMINALS AND BE BRIEF IN DURATION. && .MARINE... TODAY-TONIGHT...WEAK FRONTAL BOUNDARY OVER THE SOUTHERN WATERS WAS CAUSING A NORTHEAST WIND FLOW AROUND 10 KNOTS EXCEPT FOR WEST/NORTHWEST WINDS 5-10 KNOTS IN THE SOUTH. THE MODELS DO NOT SHOW MUCH CHANGE EXCEPT TO SWING WIND AROUND IN THE SOUTH TO NORTHEASTERLY. BUOYS INDICATE SEAS 2-3 FEET AND DO NOT EXPECT MUCH CHANGE. DOMINANT WIND WAVE PERIODS AROUND 5 SECONDS WILL CAUSE AN UNCOMFORTABLE CHOP FOR SOME SMALL CRAFT OPERATORS NORTH OF SEBASTIAN INLET. && .HYDROLOGY... THE SHINGLE CREEK AT CAMPBELL REMAINS JUST ABOVE ACTION STAGE. LATEST GAUGE INFORMATION SHOWS THE CREEK HAS LEVELED OFF. ANY ADDITIONAL HEAVY RAINFALL COULD STILL RESULT IN FURTHER RISES. THE ST. JOHNS RIVER AT ASTOR REMAINS SLIGHTLY ABOVE FLOOD STAGE AND IS FORECAST TO REMAIN IN MINOR FLOOD THROUGH THE END OF THE WEEK. RIVER LEVELS ARE FORECAST TO REACH ACTION STAGE AT LAKE HARNEY TODAY AND ON FRIDAY AT DELAND. IF ADDITIONAL HEAVY RAINFALL SETS UP OVER OR UPSTREAM FROM THESE AREAS...THERE WILL BE FURTHER AGGRAVATION OVER THE BASIN. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. && $$ FORECASTS...LASCODY IMPACT WEATHER...SHARP
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1104 AM CDT THU OCT 2 2014 .DISCUSSION... 317 AM CDT RAINFALL AND THE POTENTIAL FOR SEVERE THUNDERSTORMS WILL BE THE MAIN FOCUS OF THIS COMPLEX FORECAST PERIOD...WITH UNSEASONABLY COLD AIR SPREADING IN BEHIND A STRONG COLD FRONT FOR THE WEEKEND. WATER VAPOR IMAGERY SHOWS A MASSIVE UPPER TROUGH OVER MOST OF CENTRAL AND WESTERN NORTH AMERICA WITH NUMEROUS WAVES EMBEDDED WITHIN THE FLOW TRIGGERING AREAS OF THUNDERSTORMS. SEVERAL OF THESE WAVES ARE LINED UP FROM TX/OK TO EASTERN WISCONSIN. AT THE SURFACE...LOOSELY ORGANIZED LOW PRESSURE IS OVER OKLAHOMA WITH A WARM FRONT EXTENDING EASTWARD FROM IT ACROSS CENTRAL MISSOURI AND SOUTH-CENTRAL ILLINOIS. WARM/MOIST ASCENT IS DRIVING CLUSTERS OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF NORTHERN MISSOURI AND CENTRAL ILLINOIS IN CONJUNCTION WITH AT LEAST ONE OF THE ABOVE MENTIONED UPPER WAVES. TODAY AND TONIGHT...THE UPPER WAVE AIDING THE SHOWER/THUNDER DEVELOPMENT OVER THE LOCAL AREA WILL LIFT OFF TO THE NORTHEAST THIS MORNING WITH CURRENT BANDS OF SHOWERS AND EMBEDDED THUNDER WILL EXIT TO THE NORTHEAST BY MID MORNING OR SO. SOME SPOTTY SHOWERS/THUNDER MAY LINGER THROUGH EARLY AFTERNOON BUT THERE IS NOT MUCH SUPPORT FOR LARGE SCALE PRECIP DEVELOPMENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON...WITH CURRENT CONVECTION ALSO HELPING TO LIMIT THE INCOMING MOISTURE FLUX. THE SURFACE LOW WILL BEGIN TO LIFT NORTHEAST AND BECOME MARGINALLY BETTER ORGANIZED THROUGH THE AFTERNOON AS THE MAIN UPPER TROUGH AXIS CURRENTLY PUSHING TOWARD WESTERN KS/OK/TX ADVANCES EASTWARD. IT DOES APPEAR THAT ONE OR SEVERAL MID/UPPER WAVES WILL LIFT NORTHEASTWARD AHEAD OF THE MAIN TROUGH WITH AT LEAST ONE CURRENTLY PRODUCING NEW CONVECTION ACROSS OKLAHOMA. THIS MAY RESULT IN AN INCREASE IN CONVECTION LOCALLY FROM MID TO LATE AFTERNOON...ESPECIALLY ACROSS THE WESTERN CWA. ANOTHER POTENTIAL SOURCE FOR CONVECTION WILL BE THE NORTHWARD ADVANCING WARM FRONTAL BOUNDARY WHICH IS EXPECTED TO PASS THIS AFTERNOON AND BE NORTH OF THE AREA BY THIS EVENING. CONFIDENCE IN TIMING/COVERAGE DETAILS FROM ABOUT MID MORNING THROUGH MID AFTERNOON IS LIMITED BUT WILL CONTINUE WITH THE IDEA THAT THERE WILL BE A MINIMUM OF ACTIVITY DURING THIS TIME...THOUGH THERE MAY BE SOME ACTIVITY AROUND. THE SURFACE LOW REMAINS ELONGATED AND TRACKS NORTHWARD ALONG AN INVERTED TROUGH AXIS FROM NORTHERN MISSOURI TO CENTRAL WISCONSIN BY EVENING. THE MAIN UPPER TROUGH AXIS WILL CONTINUE EAST AS WELL HELPING TO FOCUS NEW CONVECTIVE DEVELOPMENT ALONG THE COLD FRONT TRAILING THE LOW. THIS WILL LEAD TO STEADILY INCREASING COVERAGE OF SHOWERS/STORMS ACROSS THE WESTERN CWA LATE IN THE AFTERNOON WITH THE BULK OF THE ACTIVITY CROSSING THE AREA THIS EVENING AND TONIGHT AS THE LOW DEEPENS OVER NORTHERN LAKE MICHIGAN AND THE UPPER TROUGH AXIS APPROACHES. AN ORGANIZED LINE OF STORMS IS EXPECTED TO DEVELOP BUT THE MAIN QUESTION IS HOW FAR NORTH IN THE AREA IT MAY EXTEND. HEAVY RAINFALL IS A CONCERN WITH PRECIPITABLE WATER VALUES OF 1.6-1.7 INCHES. MUCH OF THE AREA SHOULD SEE AROUND AN INCH OF RAIN WITH HIGHER VALUES NEAR 2 INCHES POSSIBLE IF A LINE OF PARTICULARLY WELL ORGANIZED CONVECTION DOES CROSS THE AREA AHEAD OF A MORE WIDESPREAD AREA OF LESS INTENSE SHOWERS AND STORMS. SEVERE POTENTIAL WILL BE A CHALLENGE WITH IT CONDITIONAL ON THE EXTENT OF THE ACTIVITY ACROSS THE AREA TODAY. BETTER INSTABILITY WOULD LIKELY NEED TO BE ADVECTED IN WITH THE PASSAGE OF THE WARM FRONT. DEEP LAYER SHEAR WILL BE STRONG AS WILL THE OVERALL LARGE SCALE FORCING SO EVEN WEAK INSTABILITY COULD PRODUCE SEVERE WEATHER...WITH GUIDANCE SHOWING AROUND 1000 J/KG OF CAPE DEVELOPING BY LATE DAY WHICH WOULD BE PLENTY TO INCREASE THE SEVERE THREAT. DAMAGING STRAIGHT LINE WINDS WILL BE THE PRIMARY THREAT BUT A WELL DEVELOPED SQUALL LINE COULD SPAWN A FEW SHORT LIVED TORNADOES PROVIDED STRONG LOW LEVEL INSTABILITY DEVELOPS AND THERE IS SUFFICIENT LOW LEVEL TURNING. UNFORTUNATELY THERE ARE STILL TOO MANY UNCERTAIN VARIABLES TO HAVE GOOD CONFIDENCE IN THE THREAT FOR SEVERE WEATHER. FRIDAY AND SATURDAY...THE SURFACE LOW WILL BE MOVING INTO CENTRAL ONTARIO FRIDAY MORNING WITH THE COLD FRONT EXITING THE EASTERN CWA. THE EXIT OF RAIN TO THE EAST MAY LAG THE FRONT THANKS TO THE UPPER TROUGH AXIS STILL CROSSING THE AREA. ANOTHER PUSH OF ENERGY WILL BE RACING SOUTHEAST ACROSS THE PLAINS FRIDAY NIGHT SPAWNING AMPLIFICATION OF ANOTHER UPPER TROUGH AXIS WHICH WILL CROSS THE AREA FRIDAY AFTERNOON. THIS WILL LIKELY BRING ANOTHER ROUND OF SHOWERS WITH IT. YET ANOTHER WAVES RACES DOWN THE BACK SIDE OF THE NOW VERY AMPLIFIED LONGWAVE TROUGH HELPING IT TO CLOSE OFF OVER WISCONSIN FRIDAY NIGHT WHICH THEN LEADS TO ANOTHER EMBEDDED TROUGH AXIS PIVOTING ACROSS THE AREA SATURDAY...LEADING TO ADDITIONAL LOW CHANCES FOR SHOWERS DURING THE MORNING/MIDDAY. THE BIGGER STORY HOWEVER WILL BE THE PUSH OF COLD AIR BROUGHT IN BEHIND THE COLD FRONT FRIDAY. H85 TEMPS WILL CRASH TO ABOUT -2C BY FRIDAY EVENING. HIGHS FRIDAY WILL LIKELY OCCUR EARLY WITH TEMPS FALLING INTO THE UPPER 40S/LOWER 50S BY EVENING WITH GUSTY WEST-NORTHWEST WINDS. LOWS WILL FALL INTO THE UPPER 30S WITH FROST DEVELOPMENT UNLIKELY THANKS TO WINDS AND CLOUDS AS WELL AS SOME SHOWERS. HIGHS SATURDAY WILL ONLY REACH THE LOWER 50S AND SOME AREAS OF THE NORTHWEST MAY BE HELD INTO THE UPPER 40S. LOWS SATURDAY NIGHT WILL SHOULD FALL INTO THE MID TO UPPER 30S AS A WEAK RIDGE AXIS ARRIVES BY SUNDAY MORNING. WINDS MAY STAY STRONG ENOUGH AND CLOUD COVER EXTENSIVE ENOUGH TO PRECLUDE WIDESPREAD FROST DEVELOPMENT. MID LEVEL TEMPS WARM LATER SUNDAY BUT CLOUDS AND PRECIP MAY TEMPER WARMING SO AM EXPECTING HIGHS IN THE MID TO UPPER 50S WITH 60 POSSIBLE FAR SOUTH. SUNDAY THROUGH WEDNESDAY...THE EXPANSIVE UPPER TROUGH AND ASSOCIATED CYCLONIC FLOW WILL REMAIN IN PLACE THROUGH TUESDAY BEFORE IT STARTS TO TRANSITION NORTHEAST AND MUCH LOWER AMPLITUDE FLOW BUILDS IN. THIS WILL SET THE STAGE FOR THE PASSAGE OF EMBEDDED SHORTWAVES AND THEREFORE PERIODIC SHOWER CHANCES WITH MONDAY LOOKING TO BE A PERIOD OF HIGHER CHANCES FOR PRECIP. MID LEVELS WILL GRADUALLY WARM THOUGH SOME COOLING AND WARMING WILL BE MODULATED BY THE PASSAGE OF THE WAVES BUT OVERALL SURFACE TEMPS WILL BE ON A SLOW UPWARD TREND INTO MID WEEK...WITH UPPER 60S/LOWER 70S POSSIBLE AGAIN BY WEDNESDAY. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * INCREASING CHANCES FOR SHOWERS/THUNDERSTORMS LATE THIS AFTERNOON INTO THE EVENING...WITH SHOWERS LIKELY PERSISTING OVERNIGHT. * MVFR AND IFR LIKELY TONIGHT INTO FRIDAY MORNING...LIFR POSSIBLE LATE TONIGHT. * WIND SHIFT TO THE WEST NORTHWEST WITH FROPA EARLY FRIDAY MORNING...WITH INCREASING SPEEDS THROUGH THE END OF THE FORECAST PERIOD. RODRIGUEZ/KB //DISCUSSION...UPDATED 12Z... BULK OF MOST ACTIVITY REMAINING OUTSIDE OF THE TERMINAL AREAS THIS MORNING...BUT WITH SOME ISOLATED LIGHT SHOWERS MOVING OVERHEAD. EXPECT CURRENT SHOWERS/THUNDERSTORMS TO THE SOUTH TO REMAIN TO THE SOUTH AS THIS PRECIP DRIFTS TO THE EAST THIS MORNING. WITH THE DEPARTURE OF THE SHOWERS THIS MORNING EXPECT RELATIVELY DRY CONDITIONS FOR MOST OF TODAY...OUTSIDE OF A STRAY SHOWER OR TWO. AN ISOLATED AREA OF MVFR CEILINGS HAVE DEVELOPED ACROSS NORTHEAST ILLINOIS THIS MORNING...WHILE A MORE SOLID AREA OF LOW CLOUDS IS SITUATED OVER THE EASTERN IOWA AND FAR WESTERN ILLINOIS AREA. THE ISOLATED AREA SHOULD DISSIPATE OVER THE NEXT COUPLE OF HOURS...WHILE THE LOW CLOUDS TO THE WEST REMAINING IN THIS LOCATION FOR MOST OF TODAY. THE ONLY TERMINAL WHICH WILL LIKELY OBSERVE AN EXTENDED PERIOD OF MVFR CEILINGS TODAY WILL BE RFD. ACTIVITY WILL LIKELY INCREASE VERY LATE THIS AFTERNOON INTO THE EVENING WITH THE ARRIVAL OF BETTER LARGE SCALE SUPPORT FOR SHOWERS AND THUNDERSTORMS. STILL SOME UNCERTAINTY WITH EXACT TIMING AND DURATION BUT AT THIS TIME...A LATER START TIME DOES APPEAR LIKELY AND HAVE REFLECTED THIS IN THE TAFS. THUNDERSTORMS WILL LIKELY REMAIN OVERHEAD FOR A PORTION OF THE EVENING BUT WITH INSTABILITY DIMINISHING OVERNIGHT...FEEL THAT A TREND TOWARDS MORE SHOWERS WILL OCCUR OVERNIGHT AND THEN CONTINUE INTO FRIDAY MORNING. THE ARRIVAL OF THE BETTER LARGE SCALE SUPPORT WILL BE ACCOMPANIED WITH THE ARRIVAL OF A SURFACE TROUGH FROM THE WEST. THIS WILL MARK THE ARRIVAL OF ALREADY PRESENT IFR CEILINGS...WITH THESE CEILING LIKELY CONTINUING THROUGH FRIDAY MORNING. THERE IS THE POTENTIAL FOR LIFR AS WELL...BUT CONFIDENCE IS LOW WITH THIS POSSIBILITY AT THIS TIME. FROPA SHOULD QUICKLY MOVE ACROSS THE TERMINALS FRIDAY MORNING...WITH WINDS QUICKLY SHIFTING TO THE WEST AND OBSERVING A CONTINUED INCREASING TREND. RODRIGUEZ //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM HIGH CONFIDENCE WITH WIND SPEED/DURATION. * MEDIUM HIGH CONFIDENCE OF SHOWERS/THUNDERSTORMS...LOW MEDIUM CONFIDENCE OF TIMING. * MEDIUM HIGH CONFIDENCE OF MVFR/IFR TONIGHT...LOW MEDIUM CONFIDENCE OF LIFR. * HIGH CONFIDENCE OF WIND SHIFT AND SPEEDS WITH FROPA FRIDAY MORNING...MEDIUM CONFIDENCE OF EXACT TIMING. RODRIGUEZ/KB //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...CHANCE OF SHRA. SATURDAY...CHANCE OF SHRA. SUNDAY...SLIGHT CHANCE OF SHRA. MONDAY...CHANCE OF SHRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 441 AM CDT SURFACE RIDGE OF HIGH PRESSURE SPANS THE ATLANTIC COAST AND LOW PRESSURE IS OVER THE SOUTHERN PLAINS THIS MORNING...WITH SOUTH TO SOUTHEAST WINDS CURRENTLY BEING OBSERVED ACROSS THE LAKE. THE SURFACE PATTERN HAS TIGHTENED THIS MORNING AND HAS RESULTED IN SOME SLIGHT INCREASE IN SPEEDS...MAINLY ACROSS THE SOUTH HALF OF THE LAKE WHERE 15 TO 25 KT WINDS ARE BEING OBSERVED. THESE CURRENT SPEEDS WILL LIKELY DIMINISH THIS MORNING...WITH SOUTH WINDS OF 10 TO 20 KT BEING OBSERVED FOR THE REST OF THE DAY. THE LOW PRESSURE OVER THE SOUTHERN PLAINS WILL LIFT NORTHEAST TO THE UPPER MISSISSIPPI VALLEY TODAY...AND THEN CONTINUE NORTHEAST TO THE CENTRAL GREAT LAKES TONIGHT INTO EARLY FRIDAY MORNING WHILE ALSO STRENGTHENING. THIS WILL RESULT IN A VARYING WIND DIRECTION AS WELL AS AN INCREASE IN SPEEDS THROUGH FRIDAY. ALTHOUGH WINDS WILL BE INCREASING THROUGH THIS PERIOD...IT APPEARS THAT SPEEDS WILL REALLY RAMP UP LATE FRIDAY AFTERNOON INTO THE EARLY EVENING. WEST GALES DO APPEAR TO BE A DEFINITE POSSIBILITY FRIDAY NIGHT INTO EARLY SATURDAY MORNING OVER THE SOUTHERN HALF OF THE LAKE...AND SO ISSUED A GALE WATCH. THE NEARSHORE WATERS WILL BE ON THE FRINGE OF THE STRONGEST WINDS BUT WITH THE INDIANA NEARSHORE WATERS POSSIBLY OBSERVING THESE GALES AS WELL...DID GO AHEAD AND INCLUDE A PORTION OF THE INDIANA NEARSHORE ZONES. AS THE LOW CONTINUES NORTH THROUGH ONTARIO TO HUDSON BAY SATURDAY AND SATURDAY NIGHT...WEST WINDS TO 30 KT WILL LIKELY CONTINUE BEFORE DIMINISHING ON SUNDAY. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WATCH...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744- LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876- LMZ878...4 PM FRIDAY TO 9 AM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1029 AM CDT Thu Oct 2 2014 .UPDATE... ISSUED AT 1029 AM CDT THU OCT 2 2014 Short break in the rain occurring over a large part of the forecast area this morning, however a large area of showers and thunderstorms was beginning to spread into the far western CWA. Latest HRRR guidance has this overspreading many areas west of I-55 into early afternoon, but the model has not been handling the narrow axis along the I-70 corridor very well. Storms expected to increase across the eastern CWA during the afternoon. Main cold front is still well off to the west, and should start to move into the western CWA during the evening hours. The rain trends should rapidly decrease behind the front after its passage overnight. Main question for this afternoon/evening will be with severe weather potential. Right now only areas east of I-55 are seeing scattered breaks in the clouds. MUCAPE values around 500 J/kg or so across the south half of the forecast area, per SPC mesoanalysis. RAP soundings from Springfield do bring CAPE`s up to around 1500 J/kg during the late afternoon as the precipitation becomes more concentrated west of the I-55 corridor. Rather moist soundings do favor heavy rain, with precipitable water around 1.8 inches which is near the 99th percentile for early October. Any severe weather that occurs will be more of a wind threat in our area due to the moist profile. && .SHORT TERM...(Today) ISSUED AT 258 AM CDT THU OCT 2 2014 06z/1am surface analysis shows warm front extending from central Missouri eastward into the Ohio River Valley. Several clusters of convection have been tracking along/north of the front overnight, aided by a 30-35kt 850mb jet streak oriented from the Southern Plains northeastward across the boundary. This activity will continue for the next few hours, but should begin to wane by mid-morning as front lifts further northward. Based on current radar trends and 00z model data, will carry likely PoPs along/northwest of I-70 through midday, with only chance PoPs further south. Meanwhile, low pressure developing over Oklahoma will track northeastward into southern Wisconsin by this evening. Line of thunderstorms is expected to develop along/ahead of associated cold front, with most model solutions keeping this convection just west of the KILX CWA until late afternoon/early evening. Have increased PoPs to categorical across the Illinois River Valley this afternoon in case storms get going faster than anticipated, but think bulk of activity will hold off until evening. Aside from the rain chances today, it will be another very warm day with highs ranging from the middle 70s far northwest around Galesburg to the middle 80s along/south of I-70. && .LONG TERM...(Tonight through Wednesday) ISSUED AT 258 AM CDT THU OCT 2 2014 Latest Day 1 convective outlook from SPC places all of central/southeast Illinois under a slight risk for severe weather tonight. With a very warm/humid air mass surging northward ahead of an approaching cold front, resulting CAPE values will likely exceed 1500J/kg later today. In addition, low-level wind shear will be increasing with 0-6km bulk shear values generally in the 30-40kt range. These favorable parameters combined with strong convergence along the cold front will lead to the development of a line of thunderstorms this evening. Models generally develop the storms along the Mississippi River by late afternoon, then push them eastward to the I-55 corridor by mid-evening and into east-central Illinois shortly after midnight. Main severe weather threat will be strong/damaging winds, although highest probabilities for widespread severe will likely remain further southwest from the St. Louis area southwestward to Texas. With precipitable water values climbing over 1.75, high rainfall rates will be likely with any storms that develop. Localized flash flooding may develop within the strongest storms: however, recent rainfall amounts have not been great enough over a wide enough area to warrant a Flash Flood Watch at this time. Front will push into Indiana by Friday morning, bringing an end to the greatest rain chances. Still some model discrepancy concerning timing of frontal departure, with the ECMWF being the slowest. Have therefore hung on to chance PoPs early Friday morning along/east of I-57. A secondary upper wave currently evident on water vapor imagery over Alberta will dive southeastward Friday afternoon/evening, amplifying the mean trough over the Great Lakes/Midwest. Synoptic lift and steep mid-level lapse rates associated with this feature will be enough to warrant a slight chance for showers, mainly during the afternoon. Main weather story on Friday will be the windy and sharply cooler conditions. Tightening pressure gradient between departing front and approaching Canadian high pressure will lead to strong W/NW winds gusting to between 30 and 35mph. Temperatures will struggle to rise much at all from morning lows, with readings remaining in the 60s. With 850mb temps progged to drop into the -3 to -5C range, low temperatures by Saturday morning will fall into the middle 30s...representing a nearly 50 degree temp drop from expected high temps today! Due to a continued brisk northwesterly breeze, am not expecting any frost to develop Friday night. Heart of cold air mass will be in place across Illinois on Saturday, with highs struggling to reach the middle to upper 50s and overnight lows once again dropping into the middle to upper 30s. With much lighter winds expected, a few patches of frost will be possible by Sunday morning, especially if skies can remain clear ahead of the next approaching short-wave trough. After that, the Midwest will be dominated by northwesterly upper-level flow through Tuesday before trough retreats into Canada by the middle and end of next week. This will mean continued below normal temps in the 60s through Tuesday, followed by a warming trend and a return to the 70s by Wednesday and Thursday. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) ISSUED AT 700 AM CDT THU OCT 2 2014 The timing of thunderstorms over the next 24 hours will be the main concern, and the associated IFR/LIFR conditions during storms. Based on current radar trends, there should be a break in the showers and storms at all terminals this morning. SPI will see the return of some storms the soonest as a band of storms moves out of NE Missouri and reaches SPI as soon as 16z. That convection could reach to DEC as well, and have indicated that in the TAFS. PIA, BMI and CMI could remain dry for a longer period, possibly well into the afternoon or early evening. CMI looks to be closer to the current storm track, so may see a few showers pass close by to the south during the day. The main threat for strong to severe storms looks to be this evening for PIA, SPI and BMI. A 3-hour tempo for heavy rain and storms with IFR conditions was included in the TAFs for the current best-estimate on timing of the line of storms. We estimated 00z for PIA and 04z for CMI, but those hours may need adjustment as the cold frontal timing becomes more apparent. After the cold front passes, winds will begin to shift to the SW then W, with some gusts possible by morning. Also, MVFR clouds are likely to persist through 12z/7am Friday. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Geelhart SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
602 AM CDT THU OCT 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CDT THU OCT 2 2014 LOOKING AT WIND OBS THE PAST COUPLE OF HOURS...IT LOOKS LIKE THE COLD FRONT WHICH JUST BARELY MADE IT INTO WRN MN WEDNESDAY EVENING HAS FINALLY STARTED TO MOVE. STARTING TO SEE MORE LIGHT NW WIND OBS IN MN AND AT 330 AM...THE WIND SHIFT LOOKS TO BE PRETTY CLOSE TO I-35. THE MOISTURE BOUNDARY THOUGH HAS NOT FOLLOWED THE WIND SHIFT...AS IT WAS STILL BACK ALONG A RWF TO BRAINERD LINE AT 330 AM. LIGHT WINDS AND A JUICED BOUNDARY LAYER THANKS TO RAINS WEDNESDAY HAS ALLOWED FOR SOME RATHER UGLY CONDITIONS TO DEVELOP ALONG AND EAST OF THE MOISTURE BOUNDARY. WITH WINDS REALLY NOT PICKING UP MUCH TODAY...COMBINED WITH UPPER CLOUDS MOVING OVER THE TOP OF THE STRATUS/FOG...NOT EXPECTING THE LOW STRATUS TO GO VERY FAR TODAY. GIVEN THE MOSTLY CLOUDY SKIES AND THE EXPECTATION OF ANOTHER RAINY AFTERNOON...CUT BACK ON HIGHS ACROSS MUCH OF THE AREA...KEEPING THEM MAINLY IN THE LOWER 60S...THOUGH DEPENDING ON WHERE THE MAIN PRECIP BAND SETS UP TODAY...THERE WILL LIKELY BE A STRIP ACROSS THE CENTER OF THE CWA THAT REMAINS IN THE 50S. AS ALLUDED TO ABOVE...THERE IS ANOTHER ROUND OF PRECIP ON ITS WAY. CURRENTLY ITS DOWN ACROSS NE NEB AND SE SODAK. THE PRECIP THAT WILL BE COMING THIS DIRECTION WILL BE ROOTED ON A STRONG BAND OF FGEN IN THE H7-H6 LAYER. THE 02.00 GFS AND NAM AGREE ON THIS BAND...BUT DIFFERED SIGNIFICANTLY ON WHERE IT WOULD GO. THE GFS HAS THE CENTER OF THE BAND GOING UP A RWF/STC LINE...WHILE THE NAM WAS WE OVER ALONG AND EVEN A LITTLE EAST OF AN AEL/EAU LINE...THOUGH THE 02.06 NAM DID SHIFT THE BAND WEST. WHEN LOOKING AT THE RAP/HRRR/HOPWRF/NMM/ARW...THEY ALL AGREE NICELY WITH WHAT THE GFS HAS...SO FAVORED THE POP/QPF FORECAST TODAY TOWARD A GFS/CAM BLEND. OTHER CHANGE MADE TO THE FORECAST WAS TO REMOVE THE MENTION OF THUNDER...AS ELEVATED INSTABILITY WILL BE REMAINING SOUTHEAST OF THE MPX CWA. TONIGHT...PRECIP WILL QUICKLY CLEAR OUT OF WRN WI BETWEEN 2Z AND 6Z. BEHIND THIS PRECIP...WE WILL START TO SEE SOME STRONGER PRESSURE RISES MOVE INTO WRN MN. THIS WILL START BRINGING IN SOME BETTER THAN 10 KT WINDS OUT INTO WRN MN LATE IN THE NIGHT. THE OTHER ADVANTAGE TO THE INCREASING PRESSURE GRADIENT AND WINDS IS THAT THIS WILL FINALLY HELP FLUSH THE LOW STRATUS OUT OF THE MPX AREA. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 339 AM CDT THU OCT 2 2014 THE FOCUS ON FRIDAY REMAINS ON THE STRONG NORTHWEST FLOW AND NEAR WIND ADVISORY CONDITIONS IN WESTERN MN AS THE SURFACE LOW MOVES EAST OF THE FORECAST AREA AND DEEPENS OVER THE GREAT LAKES. WE ARE BECOMING A BIT MORE COMFORTABLE IN HOLDING OFF ON ISSUING A WIND ADVISORY GIVEN THE SLIGHT DOWNWARD TREND IN THE FORECAST WINDS SPEEDS AT THE TOP OF THE BOUNDARY LAYER. YESTERDAY`S NAM WAS SHOWING MORE 44-49KTS NEAR THE TOP OF THE CHANNEL AND THIS MORNING`S RUN...ALONG WITH THE GFS ARE GENERALLY 38-43KTS. WE WILL STILL BE EFFICIENT IN BRING THESE WINDS TO THE GROUND DUE TO THE GOOD MIXING. THE SLOWER TREND WITH THIS INCOMING SYSTEM ALSO MEANS MOST OF FRIDAY COULD BE PRECIP FREE AS WE END UP IN THE DRY SLOT...WITH THE TRAILING WEAK TROUGH AND UPPER LOW NOT SWINGING THROUGH UNTIL FRIDAY NIGHT. THE TIMING MIGHT ACTUALLY SUPPORT A FEW MORE SNOW FLAKES MIXING IN LATE FRIDAY NIGHT AND EARLY SATURDAY MORNING AS TEMPERATURE PROFILE COLLAPSE AND THE FREEZING LEVEL DROPS TO NEAR 1000FT WHILE THE LIGHT PRECIP IS STILL ONGOING IN THE EASTERN HALF OF MN AND IN WESTERN WI. THE SURFACE TEMP AND GROUND TEMP ARE TOO WARM FOR EVEN MINOR ACCUMULATIONS...BUT NONETHELESS WE`RE ABOUT A COUPLE WEEKS AHEAD OF SCHEDULE FROM WHEN WE TYPICALLY SEE OUR FIRST FLAKES. THE GFS/NAM/ECMWF/GEM ALL HAVE SNOW ACCUMULATIONS ACROSS FAR NORTHERN MN...WITH THE POTENTIAL FOR DOUBLE DIGIT /INCHES/ SNOWFALL IN SOUTHERN MANITOBA AND ONTARIO. CYCLONICALLY CURVED FLOW AND COOL FALL AIR WILL REMAIN IN PLACE THROUGH EARLY NEXT WEEK. IT SHOULD ALSO BE MAINLY DRY. THE ECMWF IS STILL MORE AGGRESSIVE IN BRINGING BACK WARMER TEMPS BY THE MIDDLE OF NEXT WEEK AS IT JETTISONS A CLOSED UPPER LOW IN THE APPALACHIANS AND LIFTS THE MAIN LONGWAVE TROUGH NORTH OF THE CONUS FASTER THAN THE GFS. THE PATTERN IS EVOLVING SLOWER AND TEMPS EARLY NEXT WEEK SHOULD REMAIN COOLER THAN WHAT WAS FORECAST YESTERDAY AND THE DAY BEFORE. IT`S GOING TO BE TOUGH TO SHAKE THE 40S AND 50S UNTIL AT LEAST TUESDAY...MAYBE WEDNESDAY DEPENDING ON CLOUD COVER. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 543 AM CDT THU OCT 2 2014 ONLY CHANGE TO CONDITIONS DURING THE MORNING WAS TO IMPROVE VSBYS...LOW STRATUS CURRENTLY IN PLACE IS HERE TO STAY FOR SOME TIME WITH MID/HIGH CLOUDS STREAMING ACROSS THE STATE FROM THE NEXT WAVE TO THE SW HELPING TO LIMIT MIXING. DID NOT CHANGE MUCH WITH THE TAF IN TERMS OF TIMING FOR ARRIVAL OF RAIN...OTHER THAN TO SPEED IT UP A BIT. WENT ABOUT AN HOUR FASTER THAN THE HRRR AS IT HAS BEEN INITIALIZING A BIT SLOW WITH THE PRECIP THIS MORNING. CIGS IN THAT RAIN RIGHT NOW ARE MAINLY VFR...SO TRIED TO SHOW SOME MORE CIGS INTO THE HIGHER MVFR CATEGORY AS THE RAIN COMES IN. WILL SEE CONDS IMPROVE TO VFR QUICKLY BEHIND THE RAIN...WITH THE THREAT FOR MVFR CIGS RETURNING TO THE NW AFTER 9Z. WILL START PICKING UP GUSTS AFTER 6Z AT RWF/AXN...WITH MSP PICKING UP ON THE GUSTS SHORTLY AFTER 12Z FRIDAY. KMSP...MSP IS OUT OF THE WOODS FOR DENSE FG...BUT LIFR/IFR CIGS THROUGH AT LEAST 16Z WILL KEEP THINGS RUNNING A BIT SLOWER. CONFIDENCE REMAINS HIGH IN ANOTHER BAND OF RAIN MOVING ACROSS THE FIELD EARLY THIS AFTERNOON. WILL LIKELY SEE VIS DROP BACK DOWN TO MVFR AS THE HEAVIEST RAIN MOVES THROUGH. DECIDED TO MOVE THE CIGS ABOVE 017 WHEN THE HEAVIER RAIN MOVES IN AS WELL BASED ON THE FACT THAT OBS IN THE RAIN SHIELD NOW HAVE CIGS RANGING FROM 020-050. BY THE END OF THE TAF...WILL LIKELY BE SEEING NW WINDS GUSTING TO BETWEEN 25 AND 30 KTS. /OUTLOOK FOR KMSP/ FRI NIGHT...MAINLY MVFR WITH CHC -SHRA. WINDS WNW 15G25 KTS. SAT...CHC MVFR CIGS. WINDS NW 10-15 KTS. SUN...VFR. WINDS WNW 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR MNZ042>045- 049>053-057>063-065>070-074>078-082>085-091>093. WI...DENSE FOG ADVISORY UNTIL 10 AM CDT THIS MORNING FOR WIZ014-015- 023>026. && $$ SHORT TERM...MPG LONG TERM...CLF AVIATION...MPG
AREA FORECAST DISCUSSION
NWS SPRINGFIELD MO
552 AM CDT Thu Oct 2 2014 ...12Z Aviation Forecast Update... .SHORT TERM...(Today and Tonight) Issued at 222 AM CDT THU OCT 2 2014 There will be active weather during the morning commute for some across the Missouri Ozarks and southeast Kansas. Convection has been redeveloping across northeast Oklahoma and southeast Kansas moving slowly to the northeast. The HRRR has been handling this well and will see this convection continue mainly along and north of I-44 through mid morning. There will be a risk for stronger convection to develop this morning with large hail and damaging wind gusts the main threat along with frequent lightning and heavy rainfall. The short term models are in good agreement with the advancing cold front moving into southeast Kansas by mid afternoon. Initially discreet convection will develop along and just ahead of the front between 18-20z. This convection will quickly merge into a squall line or line segments as the line advances rather quickly eastward. Followed the HRRR closely for the afternoon convection. All modes of severe weather will be possible with damaging winds being the main threat...followed by large hail...and the risk of a couple isolated tornadoes. The line of storms will be near the Joplin area by 4 pm and Springfield area by 6 pm. The line will be clearing the eastern Missouri Ozarks before midnight this evening. Will leave the ongoing Flash Flood Watch as is with the heaviest storm total rainfall expected in the watch area where totals will be between 2 to 5 inches. Areas southeast of I-44 will see totals between 1 to 2 inches. .LONG TERM...(Friday through Wednesday) Issued at 222 AM CDT THU OCT 2 2014 Friday will be a blustery and much cooler day with passing clouds and perhaps some sprinkles or spotty light shower or two. The latest guidance shows a piece of upper level energy moving across the area especially the central Missouri area with some clouds and sprinkles possible. Winds will be gusty up to 25 mph and temperatures struggling to get above 60 degrees. Skies will clear Friday evening for Friday night football around the Missouri Ozarks but it will be chilly. The big question will be the frost potential. Guidance is a degree or two colder again with lows down in the middle to upper 30s likely. Wouldn`t be surprise a few colder spots that are protected get down in the lower 30s. Winds will possibly remain up around 5 mph or so. Will put back in the mention of patchy frost into the forecast especially valleys and wind protected areas. The frost potential will need to be looked at again over the next day for any possible headlines by Friday. People with sensitive outdoor plants will need to pay attention to the forecast for Friday night. Seasonably cool temperatures will stay around for the weekend and mostly dry conditions and a northwest flow. Guidance shows another weak mid level disturbance moving through on Monday with a few more clouds and possible light showers. The overall flow will flatten by the middle of next week with southerly winds returning. A moderation in temperatures will return with above normal temperatures by middle next week. && .AVIATION...(For the 12Z TAFS through 12Z Friday Morning) Issued at 521 AM CDT THU OCT 2 2014 The main aviation concerns for pilots flying in and out of the Missouri Ozarks region will be strong to severe convection developing today through this evening. On going convection this morning will affect mainly JLN and later SGF. There will be a small break in convection around midday with additional strong to severe convection developing by mid to late afternoon. Have the line of convection moving from west to east affecting JLN earliest and BBG during the early evening hours. Convection will taper to VCSH by the evening. There will be ceiling and visibility drops to low end MVFR if not IFR possible under the heaviest convection. Gusty and variable winds can be expected under the strongest convection as well. Winds will generally be out of ths south today switching to northwest behind a cold front tonight. Overall trend for tonight will be a drop in ceilings to low end MVFR flirting with IFR possibly for SGF and BBG. && .SGF WATCHES/WARNINGS/ADVISORIES... MO...FLASH FLOOD WATCH through this evening FOR MOZ055>058-066>071- 077>081-088-089. KS...FLASH FLOOD WATCH through this evening FOR KSZ073-097-101. && $$ SHORT TERM...Griffin LONG TERM...Griffin AVIATION...Griffin
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
628 AM CDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 SEVERAL TIMING ISSUES WILL BE THE MAIN CONCERN IN THE SHORT TERM. INITIAL FOCUS WILL BE BAND OF SHOWERS AND STORMS STARTING TO SPREAD INTO THE AREA AT 07Z FROM CENTRAL NEBRASKA. MODELS CONTINUE TO SUGGEST A STEADY PROGRESS OF THIS SYSTEM ACROSS THE CWA TODAY IN ADVANCE OF THE UPPER TROUGH. LATEST RAP HAS THE MAJORITY OF THE PRECIP EAST OF THE AREA BY 00Z. ALSO MAY NEED A MENTION OF FOG FOR A SHORT TIME THIS MORNING IN WEST CENTRAL IOWA BETWEEN HARLAN AND RED OAK WHERE VSBY IS REPORTED NEAR ZERO. WILL MONITOR UNTIL ISSUANCE FOR ANY CHANGE AS CLOUD COVER BEGINS TO SPREAD INTO THAT AREA. A NEW FEATURE THAT HAS SHOWN UP IN TONIGHTS MODELS IS A SECONDARY BAND OF SHOWERS BEHIND THE PRIMARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE AS IT MOVES INTO NEBRASKA TONIGHT. AT THIS POINT HAVE KEPT POPS ON THE LOW SIDE AND MAINLY FOR WESTERN AND SOUTHERN PARTS OF THE AREA AS INDICATED BY 00Z MODELS. OTHERWISE WEATHER TURNS WINDY AND COLD BEHIND THE FRONT TONIGHT INTO FRIDAY WITH GOOD POTENTIAL FOR FROST OR FREEZE ACROSS MOST OF THE AREA SATURDAY MORNING. AT THIS TIME WILL CONTINUE MENTION OF THIS POTENTIAL IN THE HWO AND WAIT UNTIL LATER FORECAST FOR HEADLINES. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 GENERALLY DRY AND WARMER IN THE EXTENDED PERIOD UNTIL TOWARDS THE END OF THE TIME FRAME WHEN ANOTHER FRONTAL SYSTEM WITH UPPER LEVEL SUPPORT DEVELOPS OVER THE REGION. POPS ON THE LOW SIDE FOR NOW DUE TO UNCERTAINTY IN POSITION AND TIMING. && .AVIATION...(12Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 625 AM CDT THU OCT 2 2014 IFR CIGS WILL BE COMMON ACROSS EASTERN NEBRASKA TAF SITES THROUGH ABOUT 18Z. SCATTERED SHOWERS ARE ALSO LIKELY TO AFFECT SITES FROM TIME TO TIME...REDUCING VSBYS TO BELOW 3SM. NORTH TO NORTHWEST WINDS OF 15 TO 25KT ARE EXPECTED THROUGH MID AFTERNOON. AFTER 21Z WINDS WILL BEGIN TO DECREASE AND CLOUDS SCATTER...WITH ONLY SCATTERED MID CLOUDS FORECAST BY 00Z. ANOTHER COLD FRONT WILL APPROACH TAF SITES LATE IN THE PERIOD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...DERGAN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
745 AM EDT THU OCT 02 2014 .SYNOPSIS...WEAK HIGH PRESSURE WILL EXTEND OVER THE AREA TODAY. A COLD FRONT WILL APPROACH FROM THE WEST FRIDAY... AND CROSS THE AREA FRIDAY NIGHT. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST OVER THE WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 240 AM THURSDAY... WEAK HIGH PRESSURE RIDGING HOLDS OVER NC THIS MORNING. FOG THUS FAR HAS BEEN A BIT LIGHTER AND MORE PATCHY THAN THIS TIME YESTERDAY... PERHAPS DUE IN PART TO AREAS OF SCT-BKN MID CLOUDS DRIFTING OVER THE AREA... ASSOCIATED WITH A WEAK MID LEVEL PERTURBATION PASSING ESE THROUGH THE REGION JUST EAST OF THE INCOMING MID LEVEL SHORTWAVE RIDGE. ADDITIONAL MID CLOUDS OVER NE NC AND TO THE NE ARE ASSOCIATED WITH THE MID LEVEL LOW JUST OFF NEW ENGLAND. WE MAY SEE A FEW SPRINKLES OVER NE PORTIONS OF THE FORECAST AREA EARLY THIS MORNING... BUT THE MOISTURE APPEARS TOO SHALLOW FOR ANY APPRECIABLE PRECIP. THE VERY LIGHT WIND FIELD IN THE LOW LEVELS SHOULD ONCE AGAIN MAKE FOR A SLOW DISSOLUTION OF THIS MORNING`S FOG... HOWEVER IF IT REMAINS MORE LIGHT AND PATCHY THROUGH DAYBREAK (IN CONTRAST TO THE HRRR WHICH DEPICTS WIDESPREAD LOW CIGS/VSBYS THROUGH SUNRISE)... WE WOULD THEN SEE SOME SUNSHINE EARLIER THAN YESTERDAY. REGARDLESS... FORECAST SOUNDINGS SHOW SUFFICIENT LOW LEVEL MOISTURE BENEATH THE SUBSIDENCE INVERSION ALOFT (JUST ABOVE 700 MB) FOR PARTLY CLOUDY SKIES FOR MUCH OF THE DAY. MANY OF THE CONVECTION ALLOWING MODELS AS WELL AS THE NAM/GFS AND SREF PROBABILITIES SUGGEST THAT A FEW SHALLOW SHOWERS WILL POP UP THIS AFTERNOON... PROMPTED BY HEATING WHICH SHOULD YIELD PERHAPS A FEW HUNDRED J/KG OF CAPE... ALMOST ALL BELOW 700 MB. THESE SHOWERS SHOULD BE ORIENTED ALONG THE DIFFUSE WARM FRONTAL ZONE MOVING NE THROUGH THE AREA LATE TODAY THROUGH TONIGHT. WILL BRING IN ISOLATED SHOWERS FROM MID-LATE AFTERNOON STRETCHING THROUGH THE EVENING AND EARLY OVERNIGHT HOURS. AS DEWPOINTS CREEP UPWARD A BIT OVERNIGHT IN THE WAKE OF THE WARM FRONTAL ZONE... EXPECT YET ANOTHER ROUND OF LIGHT FOG... BUT THIS FOG SHOULD STAY LIGHT GIVEN EXPECTATIONS OF STRATOCUMULUS TO CURB NOCTURNAL COOLING. HIGHS FROM 78 NE TO 84 SW... WITH THICKNESSES RUNNING NEARLY 10 M ABOVE NORMAL. MILD LOWS TONIGHT OF 60-64. -GIH && .SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/... AS OF 310 AM THURSDAY... LATEST MODEL OUTPUT ARE IN PRETTY CLOSE AGREEMENT ON THE TIMING OF POTENT MID LEVEL LOW ACROSS THE LOWER GREAT LAKES... ITS ATTENDING LARGE SCALE TROUGH PUSHING THROUGH EASTERN NOAM... AND THE ASSOCIATED SURFACE COLD FRONT. WE GET FULLY INTO THE WARM SECTOR DURING FRI MORNING... AND THE FRONT ITSELF SHOULD GET INTO WRN NC BY MID EVENING... AND THEN SWEEP EASTWARD OVERNIGHT... REACHING THE COASTAL PLAIN BY DAYBREAK. MOISTURE SPREADS IN FROM THE WEST AHEAD OF THE FRONT... WITH PW VALUES CLIMBING QUICKLY FROM AROUND 1 INCH TO AT OR ABOVE 1.5 INCHES DURING THE AFTERNOON HOURS. THE KINEMATICS WITH THIS SYSTEM ARE DECENT... WITH A 35-40 KT SWRLY LOW LEVEL JET ALIGNED JUST AHEAD OF THE SURFACE FRONT AND DEEP LAYER BULK SHEAR INCREASING TO 30 (EAST) TO 50 (EAST) KTS FRI NIGHT. BUT THE PROJECTED MUCAPE VALUES ARE MINOR... PEAKING AT JUST 250-500 J/KG... MADE WORSE BY THE LOSS OF HEATING WITH AN EVENING/NIGHT PASSAGE. DYNAMICS ARE BETTER BUT SIMILARLY MUTED... GIVEN THAT THE LEAD SHORTWAVE TRACKING ENE OVER NC IS RATHER WEAK... AND THE BULK OF THE HEIGHT FALLS ARE HELD TO OUR NW OVER THE MIDWEST AND OH VALLEY CLOSER TO THE MID LEVEL VORTEX. BUT GIVEN THE STRONG WIND FIELD AND UPPER DIVERGENCE MAX SHIFTING EAST THROUGH THE AREA... STILL EXPECT GOOD SHOWER/ISOLATED STORM COVERAGE. WILL BRING IN LOW CHANCE POPS WEST BY MID AFTERNOON... SPREADING EASTWARD WITH HIGH POPS TOPPING OUT AT 60-80% IN THE EVENING/OVERNIGHT... BEFORE STARTING TO PUSH OUT OF THE CWA TOWARD MORNING. OVERALL QPF LOOKS MEAGER WITH THIS EVENT... LIKELY TOTALLING A QUARTER INCH OR LESS. THE LOW POTENTIAL INSTABILITY WILL GREATLY CUT THE SEVERE THREAT... ALTHOUGH A FEW BOWING SEGMENTS MAY BRING DOWN SOME OF THE 30-40 KTS OF WIND FROM ALOFT... EVEN WITH JUST SHOWERS. HIGHS NEAR 80 NW (WHERE CLOUDS SHOULD BE FIRST TO SPREAD IN DURING THE AFTERNOON) TO 85 SE. LOWS 57 NW TO 66 SE. -GIH && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 230 AM THURSDAY... THE COLD FRONT WILL CONTINUE TO PROGRESS THROUGH CENTRAL NC EARLY SATURDAY...WITH THE PRE-FRONTAL CONVECTION ENDING FROM WEST TO EAST AHEAD OF IT...EXITING THE AREA BY NOON SATURDAY. ONCE THE RAIN ENDS SATURDAY...EXPECT DRY WEATHER THROUGH THE WEEKEND AND INTO EARLY NEXT WEEK. THERE IS STILL SOME UNCERTAINTY IN THE RAINFALL CHANCES FOR TUESDAY AND WEDNESDAY AS ANOTHER DISTURBANCE TRAVERSES THE UPPER LEVEL TROUGH AND APPROACHES THE CAROLINAS. FOR NOW WILL KEEP THE FORECAST DRY. AT THE SURFACE...COOL HIGH PRESSURE WILL BUILD INTO THE REGION BEHIND THE FRONT...MOVING NE OVER NC THROUGH THE WEEKEND AND OUT OVER THE ATLANTIC EARLY NEXT WEEK. EXPECT A RELATIVELY COOL AND COMFORTABLE TEMPERATURE FORECAST FOR THE WEEKEND...WITH HIGHS IN THE MID 60S TO LOW 70S SATURDAY AND MID 60S EVERYWHERE SUNDAY. SATURDAY NIGHT WILL BE THE COLDEST NIGHT OF THE SEASON SO FAR...LOW 40S NW TO UPPER 40S SE. SUNDAY NIGHT WILL ALSO BE CHILLY...MID 40S ACROSS THE AREA. TEMPERATURES WILL REBOUND SOME EARLY NEXT WEEK... HIGHS MAINLY IN THE LOW 70S MONDAY INCREASING TO MID TO UPPER 70S BY WEDNESDAY. LOWS 50-55 DEGREES MONDAY NIGHT...INCREASING INTO THE 55- 60 DEGREE RANGE BY WEDNESDAY NIGHT. && .AVIATION /12Z THURSDAY THROUGH MONDAY/... AS OF 745 AM THURSDAY... YET ANOTHER ROUND OF WIDESPREAD FOG WITH AREAS OF DENSE FOG AND STRATUS ACROSS CENTRAL NC THIS MORNING. CONDITIONS AT CENTRAL NC TAF SITES HAVE VARIED AMONG MVFR AND IFR/LIFR OVER THE LAST FEW HOURS... WITH THE WORST CONDITIONS AT RWI. THESE ADVERSE AVIATION CONDITIONS ARE EXPECTED TO SLOWLY IMPROVE TO MVFR AT ALL SITES BETWEEN 13Z AND 15Z... AND TO VFR BY 17Z. RAIN CHANCES REMAIN VERY LOW AT CENTRAL NC TAF SITES... ALTHOUGH PASSAGE OF A WEAK UPPER LEVEL DISTURBANCE THIS MORNING COULD BRING AN ISOLATED SPRINKLE OR TWO TO RDU/RWI. AND ADDITIONAL ISOLATED VERY LIGHT (VFR) SHOWERS ARE POSSIBLE LATE THIS AFTERNOON INTO TONIGHT ASSOCIATED WITH A WEAK WARM FRONT MOVING NORTHEASTWARD THROUGH THE AREA. WINDS WILL BE LARGELY CALM THROUGH MID MORNING... THEN REMAIN LIGHT/VARIABLE THIS AFTERNOON AND EVENING BUT PREDOMINANTLY FROM THE SE. PATCHY MVFR-IFR FOG MAY FORM ONCE AGAIN LATE IN THE TAF VALID PERIOD (AFTER 06Z FRI)... AND THIS SHOULD HOLD THROUGH DAYBREAK FRI MORNING. LOOKING BEYOND 12Z EARLY FRI MORNING... EXPECT IMPROVEMENT OF VSBYS TO VFR DURING MID-LATE FRI MORNING. A STRONG FRONTAL SYSTEM WILL BRING INCREASING SURFACE WINDS FROM THE SW AND A GOOD CHANCE OF SUB- VFR CONDITIONS IN WIDESPREAD SHOWERS AND A FEW STORMS FRI EVENING THROUGH FRI NIGHT... EXITING THE EASTERN TAFS EARLY SAT MORNING. VFR CONDITIONS SHOULD THEN RESUME SAT AFTERNOON... LASTING THROUGH MONDAY... AS HIGH PRESSURE BUILDS IN FROM THE WEST. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...HARTFIELD LONG TERM...KC AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS TULSA OK
1034 AM CDT THU OCT 2 2014 ...UPDATE... .DISCUSSION... MORNING STORMS HAVE BEHAVED ABOUT AS EXPECTED...WITH SPORADIC HAIL AND EVEN A DAMAGING WIND REPORT. EXCEPT IN A COUPLE OF STORMS...THE OVERALL INTENSITY TREND HAS BEEN DOWN SINCE SUNRISE. HRRR HANDLING THIS QUITE WELL. LEADING EDGE OF THE COLD FRONT JUST WEST OF THE FORECAST AREA AT THIS TIME...EXTENDING FROM SOUTH CENTRAL KANSAS TO ABOUT OKC AND INTO SOUTHWEST OKLAHOMA. PLENTY OF INSTABILITY CONTINUES AHEAD OF THE FRONT IN EASTERN OKLAHOMA AND WESTERN ARKANSAS...ESPECIALLY IN PARTS OF SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS THAT HAVE NOT SEEN ANY STORMS. DEEP LAYER SHEAR IS CURRENTLY RELATIVELY LOW ACROSS THE AREA...BUT WILL INCREASE THROUGH THE REST OF THE MORNING AND INTO THE AFTERNOON AS THE UPPER SYSTEM JUST EAST OF THE ROCKIES MOVES CLOSER. LARGELY UNIDIRECTIONAL SHEAR SHOULD LEAD TO A LINEAR STORM MODE...WITH DAMAGING WINDS AND LARGE HAIL THE MOST LIKELY THREATS. 0-3KM SHEAR VECTORS ARE PERPENDICULAR TO THE EXPECTED SQUALL LINE MOVEMENT...BUT THE MAGNITUDES ARE RELATIVELY WEAK...WHICH SHOULD LIMIT THE OVERALL POTENTIAL FOR LEADING EDGE TORNADOES. THE THREAT WILL DEFINITELY NOT BE ZERO THOUGH. THE MAIN LINE OF STORMS SHOULD CLEAR THE FORECAST AREA BY AN HOUR OR TWO AFTER SUNSET...IF NOT BY SUNSET IF THE HRRR TIMING VERIFIES. WITH THE MAJORITY OF THE FORECAST AREA EXPECTED TO SEE THE LINE OF STORMS BEFORE SUNSET...LOSS OF DAYTIME HEATING SHOULD NOT AFFECT THE LINES INTENSITY. HAVE INCREASED THE CONDITIONAL SEVERE PROBABILITIES THIS AFTERNOON AND EARLY EVENING ACROSS SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS TO ACCOUNT FOR THIS. PRODUCTS WILL CONTINUE TO BE UPDATED THROUGH THE LATE MORNING AND EARLY AFTERNOON TO KEEP UP WITH THE RADAR TRENDS. && .PREV DISCUSSION... /ISSUED 703 AM CDT THU OCT 2 2014/ DISCUSSION... THE 12Z TAF DISCUSSION IS INCLUDED BELOW... AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. PRETTY COMPLICATED AVIATION FORECAST TODAY...WITH LOW CIGS AND TSRA TO CONTEND WITH. THE MORNING STORMS ARE LIKELY DONE AFFECT THE TAF SITES...SO THE FOCUS THEN TURNS TO THE AFTERNOON. USED THE LATEST HRRR DATA COMBINED WITH PREV FORECAST TO HONE IN ON THE SEVERAL HOUR WINDOW OF BEST OPPORTUNITY AT EACH TAF SITE. TSRA SHOULD CLEAR ALL OF THE TERMINALS BY ABOUT 03Z THIS EVENING. AS FOR THE LOW CLOUDS...THERE IS SOME MVFR STRATUS AT KFSM AND THIS COULD MOVE INTO KMLC LATER. THE RUC/NAM MOISTURE PROFILES SUGGEST LOW CLOUDS BY LATE IN THE DAY OR EARLY EVENING BEHIND THE FRONT INITIALLY...AND THEN GRADUALLY CLEAR THINGS OUT OVER EASTERN OK TOWARD THE END OF THIS FORECAST. LACY PREV DISCUSSION... /ISSUED 411 AM CDT THU OCT 2 2014/ DISCUSSION... ELEVATED THUNDERSTORMS CONTINUE TO EXPAND WITHIN STRENGTHENING LOW LEVEL JET AXIS THIS MORNING ACROSS CENTRAL AND PARTS OF EASTERN OKLAHOMA. EXPECT THIS TO CONTINUE SHIFTING EAST THROUGH THE MORNING WITH A THREAT OF MARGINAL WIND GUSTS AND HAIL BUT SEVERE PROBABILITY SHOULD REMAIN LOW WITH THE INITIAL ACTIVITY. APPEARS NOW THAT THIS SHOULD MOVE OFF FAST ENOUGH TO ALLOW FOR SIGNIFICANT DESTABILIZATION TO OCCUR OVER LARGE PORTION OF THE FORECAST AREA THIS AFTERNOON IN ADVANCE OF PACIFIC COLD FRONT THAT CURRENTLY LIES FROM TX PANHANDLE TO NE KANSAS. UPPER WAVE EJECTING ACROSS THE PLAINS DURING THE AFTERNOON WILL INCREASE SHEAR AS WELL...LEADING TO RELATIVELY WIDESPREAD SEVERE WEATHER EVENT LATER TODAY. SHEAR PROFILES WILL BE MAINLY UNIDIRECTIONAL AND FAVOR LINEAR STORM MODE...HOWEVER SOME INITIAL ALBEIT SHORT- LIVED SUPERCELL DEVELOPMENT SEEMS PROBABLE. THUS ALL MODES OF SEVERE ARE POSSIBLE ALONG WITH HEAVY RAINFALL AMOUNTS. FRONT AND UPPER TROUGH WILL SWEEP THROUGH THE AREA THIS EVENING WITH STORMS ENDING ACROSS WESTERN ARKANSAS BEFORE 06Z. DEEP LONGWAVE TROUGH DEVELOPING OVER GREAT LAKES REGION FRI/SAT WILL HELP BRING A SECOND STRONGER SURGE OF CANADIAN AIR INTO THE AREA FRIDAY WITH A PERIOD OF GUSTY NW WINDS AND MUCH COOLER TEMPS... ESPECIALLY BY SAT MORNING WHEN MANY AREAS WILL SEE UPPER 30S AND LOW 40S. NICE WEEKEND WILL FOLLOW WITH A STRONG WARM UP SUNDAY AFTERNOON AS LOW LEVEL WINDS QUICKLY RETURN FROM THE SOUTH. A WEAK BOUNDARY WILL SLIDE THROUGH MONDAY BUT MOISTURE WILL REMAIN VERY LIMITED AT THAT TIME AND HAVE KEPT THE FORECAST DRY. UPPER RIDGE BUILDS IN FROM THE SOUTHWEST BY MID WEEK WITH MUCH ABOVE NORMAL TEMPERATURES RETURNING BY WEDNESDAY...POSSIBLY CLOSE TO WHAT WE SAW THE LAST COUPLE OF DAYS. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...22 LONG TERM....05
AREA FORECAST DISCUSSION
NWS TULSA OK
703 AM CDT THU OCT 2 2014 .DISCUSSION... THE 12Z TAF DISCUSSION IS INCLUDED BELOW... && .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. PRETTY COMPLICATED AVIATION FORECAST TODAY...WITH LOW CIGS AND TSRA TO CONTEND WITH. THE MORNING STORMS ARE LIKELY DONE AFFECT THE TAF SITES...SO THE FOCUS THEN TURNS TO THE AFTERNOON. USED THE LATEST HRRR DATA COMBINED WITH PREV FORECAST TO HONE IN ON THE SEVERAL HOUR WINDOW OF BEST OPPORTUNITY AT EACH TAF SITE. TSRA SHOULD CLEAR ALL OF THE TERMINALS BY ABOUT 03Z THIS EVENING. AS FOR THE LOW CLOUDS...THERE IS SOME MVFR STRATUS AT KFSM AND THIS COULD MOVE INTO KMLC LATER. THE RUC/NAM MOISTURE PROFILES SUGGEST LOW CLOUDS BY LATE IN THE DAY OR EARLY EVENING BEHIND THE FRONT INITIALLY...AND THEN GRADUALLY CLEAR THINGS OUT OVER EASTERN OK TOWARD THE END OF THIS FORECAST. LACY && .PREV DISCUSSION... /ISSUED 411 AM CDT THU OCT 2 2014/ DISCUSSION... ELEVATED THUNDERSTORMS CONTINUE TO EXPAND WITHIN STRENGTHENING LOW LEVEL JET AXIS THIS MORNING ACROSS CENTRAL AND PARTS OF EASTERN OKLAHOMA. EXPECT THIS TO CONTINUE SHIFTING EAST THROUGH THE MORNING WITH A THREAT OF MARGINAL WIND GUSTS AND HAIL BUT SEVERE PROBABILITY SHOULD REMAIN LOW WITH THE INITIAL ACTIVITY. APPEARS NOW THAT THIS SHOULD MOVE OFF FAST ENOUGH TO ALLOW FOR SIGNIFICANT DESTABILIZATION TO OCCUR OVER LARGE PORTION OF THE FORECAST AREA THIS AFTERNOON IN ADVANCE OF PACIFIC COLD FRONT THAT CURRENTLY LIES FROM TX PANHANDLE TO NE KANSAS. UPPER WAVE EJECTING ACROSS THE PLAINS DURING THE AFTERNOON WILL INCREASE SHEAR AS WELL...LEADING TO RELATIVELY WIDESPREAD SEVERE WEATHER EVENT LATER TODAY. SHEAR PROFILES WILL BE MAINLY UNIDIRECTIONAL AND FAVOR LINEAR STORM MODE...HOWEVER SOME INITIAL ALBEIT SHORT- LIVED SUPERCELL DEVELOPMENT SEEMS PROBABLE. THUS ALL MODES OF SEVERE ARE POSSIBLE ALONG WITH HEAVY RAINFALL AMOUNTS. FRONT AND UPPER TROUGH WILL SWEEP THROUGH THE AREA THIS EVENING WITH STORMS ENDING ACROSS WESTERN ARKANSAS BEFORE 06Z. DEEP LONGWAVE TROUGH DEVELOPING OVER GREAT LAKES REGION FRI/SAT WILL HELP BRING A SECOND STRONGER SURGE OF CANADIAN AIR INTO THE AREA FRIDAY WITH A PERIOD OF GUSTY NW WINDS AND MUCH COOLER TEMPS... ESPECIALLY BY SAT MORNING WHEN MANY AREAS WILL SEE UPPER 30S AND LOW 40S. NICE WEEKEND WILL FOLLOW WITH A STRONG WARM UP SUNDAY AFTERNOON AS LOW LEVEL WINDS QUICKLY RETURN FROM THE SOUTH. A WEAK BOUNDARY WILL SLIDE THROUGH MONDAY BUT MOISTURE WILL REMAIN VERY LIMITED AT THAT TIME AND HAVE KEPT THE FORECAST DRY. UPPER RIDGE BUILDS IN FROM THE SOUTHWEST BY MID WEEK WITH MUCH ABOVE NORMAL TEMPERATURES RETURNING BY WEDNESDAY...POSSIBLY CLOSE TO WHAT WE SAW THE LAST COUPLE OF DAYS. && .PRELIMINARY POINT TEMPS/POPS... TUL 86 52 69 42 / 80 20 0 0 FSM 89 57 74 44 / 90 80 0 0 MLC 88 54 75 43 / 90 20 0 0 BVO 83 48 67 37 / 80 20 0 0 FYV 85 48 67 35 / 90 80 0 0 BYV 85 52 66 39 / 80 90 0 0 MKO 87 52 69 39 / 90 40 0 0 MIO 84 50 65 38 / 90 70 0 0 F10 86 52 71 41 / 100 20 0 0 HHW 90 56 77 44 / 80 60 0 0 && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ AVIATION...30
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
958 AM CDT THU OCT 2 2014 .UPDATE... IT IS A WARM...MUGGY EARLY OCTOBER DAY THROUGHOUT THE REGION. A CLUSTER OF WEAK THUNDERSTORMS CONTINUE TO PUSH THROUGH NORTHEAST MISSISSIPPI INTO WEST TENNESSEE AS SOUTHERLY FLOW CONTINUES TO PULL A WARM...MOIST AIR MASS OVER THE REGION. CLOUD COVER WILL CONTINUE TO INCREASE THROUGHOUT THE DAY HOLDING TEMPERATURES BELOW 90 DEGREES. SHORT TERM MODELS HAVE COME INTO BETTER AGREEMENT ON THE TIMING OF A LINE OF STORMS ASSOCIATED WITH A COLD FRONT THAT WILL MOVE THROUGH THE MISSISSIPPI VALLEY REGION TONIGHT. NO CHANGES TO THE FORECAST ARE NEEDED AT THIS POINT. JPM3 && .PREV DISCUSSION... /ISSUED 625 AM CDT THU OCT 2 2014/ UPDATE...AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 311 AM CDT THU OCT 2 2014/ A TRICKY SEVERE WEATHER FORECAST FOR THIS AFTERNOON INTO TONIGHT. CURRENTLY...A COLD FRONT STRETCHES FROM KANSAS CITY MISSOURI TO NEAR AMARILLO TEXAS. LIGHT SOUTHERLY WINDS CONTINUE TO BRING AN INCREASE IN MOISTURE FROM THE GULF OF MEXICO. DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 60S BUT SHOULD JUMP INTO THE UPPER 60S TO LOWER 70S BY THIS AFTERNOON. LOW CLOUDS ARE RAPIDLY DEVELOPING ACROSS LOUISIANA INTO CENTRAL/SOUTHERN MISSISSIPPI. MODELS INDICATE THE CLOUDS SHOULD SPREAD ACROSS THE CWA BETWEEN 6AM-9AM. LATEST HRRR SHOWS SHOWERS SHOULD START POPPING ACROSS NORTH MISSISSIPPI BY 8 AM. BY 11AM-1PM...SHOWERS AND THUNDERSTORMS WILL RAPIDLY DEVELOP ACROSS MOST OF THE CWA AND WILL CONTINUE THROUGH THE REST OF THE AFTERNOON. THE LATEST GFS..NAM...AND ECMWF SEEM TO FALL IN LINE IN WHAT THE HRRR IS SHOWING THUS HAVE INCREASED POPS TO 60S ACROSS MUCH OF THE CWA FROM MID-MORNING INTO THE AFTERNOON. THE LOW CLOUDS MAY HANG TOUGH INTO THE AFTERNOON HOURS. THIS MAY HINDER ANY THUNDERSTORMS FROM BECOMING STRONG OR SEVERE AT LEAST DURING THE AFTERNOON HOURS. WITH ALL THE CONVECTION AND CLOUD COVER EXPECTED...HAVE KNOCKED DOWN HIGHS TODAY A TAD. DON/T REALLY SEE ANY LOCATION HITTING 90 TODAY. HIGHS SHOULD STAY IN THE MID TO UPPER 80S. SQUALL LINE IS STILL EXPECTED TO DEVELOP ALONG THE FRONT DURING THE AFTERNOON AND LATEST HRRR SHOWS IT STRETCHING FROM TULSA OKLAHOMA TO NEAR ABILENE TEXAS AROUND 2 PM. THE LINE WILL PROGRESS EASTWARD DURING THE REST OF THE AFTERNOON INTO THE EVENING HOURS. THE LINE WILL LIKELY OUTRACE THE FRONT BY THE EVENING HOURS. EXPECT BY THE TIME IT REACHES THE MIDSOUTH...IT MAY ENCOUNTER AN ATMOSPHERE AT LEAST SLIGHT WORKED OVER FROM CONVECTION THAT WILL OCCUR TODAY AND NOT AS UNSTABLE AS PREVIOUSLY THOUGHT A FEW DAYS AGO DUE TO CLOUD COVER. CAPE VALUES MAY GET TO 1500 J/KG WHICH IS STILL DECENT BUT NOT LIKE 2200 J/KG OR GREATER THAT THE NAM HAS BEEN SHOWING. MODELS ALSO CONTINUE TO BE A LITTLE SLOWER WITH TIMING. LINE MAY NOT GET INTO NORTHEAST ARKANSAS UNTIL CLOSER TO 9-10 PM. THUS INSTABILITY WILL BE WANING FROM LOSS OF DAYTIME HEATING. STILL EXPECT EASTERN ARKANSAS AND THE MISSOURI BOOTHEEL TO SEE THE BEST CHANCE OF SEEING SEVERE STORMS BUT REALLY EXPECT LINE TO START WEAKENING AS IT PUSHES EAST ESPECIALLY ONCE IT PUSHES EAST OF THE MISSISSIPPI RIVER. MAIN THREAT FROM THE LINE WILL BE DAMAGING WINDS AND LARGE HAIL. SINCE TIMING IS SLOWER HAVE HAD TO UPDATE POPS FOR FRIDAY TO KEEP THEM IN LONGER. NORTH MISSISSIPPI COULD SEE SOME REDEVELOPMENT OF THUNDERSTORMS ALONG THE FRONT DURING THE AFTERNOON HOURS. WOULD NOT BE SURPRISED IF SOME OF THESE BECAME STRONG WITH GUSTY WINDS AND SMALL HAIL. HIGH PRESSURE WILL BUILD INTO THE MIDSOUTH FOR THE WEEKEND AND WILL BRING BEAUTIFUL AUTUMN TEMPERATURES. HIGHS ON SATURDAY WILL BE IN THE MID TO UPPER 60S. LOWS SATURDAY NIGHT WILL DROP DOWN INTO THE UPPER 30S TO MID 40S. TEMPERATURES WILL JUMP BACK INTO THE 70S ON SUNDAY AS THE HIGH SHIFTS EAST. MODELS STILL DIFFER ON TIMING OF THE NEXT COLD FRONT FOR EARLY NEXT WEEK. THE ECMWF INDICATES FRONT WILL COME THROUGH SUNDAY NIGHT THROUGH MONDAY NIGHT. GFS HAS TIMING OF MONDAY NIGHT INTO TUESDAY. FOR NOW HAVE LEFT POPS AS IS WITH SMALL CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MONDAY INTO TUESDAY. DON/T REALLY EXPECT ANY COOL DOWN BEHIND THE FRONT AS AN UPPER RIDGE WILL BEGIN TO BUILD INTO THE AREA BEHIND IT. TEMPERATURES WILL LIKELY BE BACK INTO THE 80S BY WEDNESDAY. KRM AVIATION...12Z TAF CYCLE SHOWERS ARE ALREADY DEVELOPING ACROSS PORTIONS OF THE MIDSOUTH WITH NUMEROUS SHOWERS AND THUNDERSTORMS EXPECTED TO IMPACT ALL TAF SITES THIS AFTERNOON AND OVERNIGHT. PREVAILING CONDITIONS SHOULD INCLUDE OCCASIONAL MVFR CEILINGS SPREADING INTO THE REGION FROM THE SOUTHWEST BETWEEN 02/13Z AND 02Z/17Z ALONG WITH SCATTERED SHOWERS. AFTER 02Z/17Z CEILINGS LIFTING TO VFR BUT SCATTERED THUNDERSTORMS DEVELOPING. THUNDERSTORMS BECOMING MORE NUMEROUS AFTER 03/03Z AS A STRONG COLD FRONT APPROACHES FROM THE WEST. IFR OR LIFR CONDITIONS DUE TO HEAVY RAIN ALONG WITH GUSTY WINDS CAN BE EXPECTED IN ASSOCIATION WITH THUNDERSTORMS WINDS S-SW INCREASING TO 10-15 KTS WITH GUSTS TO NEAR 22 KTS AT KJBR. WINDS AFTER 03/00Z S 7-10 KTS. WINDS WILL SHIFT FROM THE WEST TO NORTHWEST BEHIND THE FRONT. TIMING IS QUESTIONABLE BUT JBR MAY SHIFT 03/08Z MEM 03/09Z...AND MKL 03/10Z. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
625 AM CDT THU OCT 2 2014 .UPDATE...AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 311 AM CDT THU OCT 2 2014/ A TRICKY SEVERE WEATHER FORECAST FOR THIS AFTERNOON INTO TONIGHT. CURRENTLY...A COLD FRONT STRETCHES FROM KANSAS CITY MISSOURI TO NEAR AMARILLO TEXAS. LIGHT SOUTHERLY WINDS CONTINUE TO BRING AN INCREASE IN MOISTURE FROM THE GULF OF MEXICO. DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 60S BUT SHOULD JUMP INTO THE UPPER 60S TO LOWER 70S BY THIS AFTERNOON. LOW CLOUDS ARE RAPIDLY DEVELOPING ACROSS LOUISIANA INTO CENTRAL/SOUTHERN MISSISSIPPI. MODELS INDICATE THE CLOUDS SHOULD SPREAD ACROSS THE CWA BETWEEN 6AM-9AM. LATEST HRRR SHOWS SHOWERS SHOULD START POPPING ACROSS NORTH MISSISSIPPI BY 8 AM. BY 11AM-1PM...SHOWERS AND THUNDERSTORMS WILL RAPIDLY DEVELOP ACROSS MOST OF THE CWA AND WILL CONTINUE THROUGH THE REST OF THE AFTERNOON. THE LATEST GFS..NAM...AND ECMWF SEEM TO FALL IN LINE IN WHAT THE HRRR IS SHOWING THUS HAVE INCREASED POPS TO 60S ACROSS MUCH OF THE CWA FROM MID-MORNING INTO THE AFTERNOON. THE LOW CLOUDS MAY HANG TOUGH INTO THE AFTERNOON HOURS. THIS MAY HINDER ANY THUNDERSTORMS FROM BECOMING STRONG OR SEVERE AT LEAST DURING THE AFTERNOON HOURS. WITH ALL THE CONVECTION AND CLOUD COVER EXPECTED...HAVE KNOCKED DOWN HIGHS TODAY A TAD. DON/T REALLY SEE ANY LOCATION HITTING 90 TODAY. HIGHS SHOULD STAY IN THE MID TO UPPER 80S. SQUALL LINE IS STILL EXPECTED TO DEVELOP ALONG THE FRONT DURING THE AFTERNOON AND LATEST HRRR SHOWS IT STRETCHING FROM TULSA OKLAHOMA TO NEAR ABILENE TEXAS AROUND 2 PM. THE LINE WILL MOVE PROGRESS EASTWARD DURING THE REST OF THE AFTERNOON INTO THE EVENING HOURS. THE LINE WILL LIKELY OUTRACE THE FRONT BY THE EVENING HOURS. EXPECT BY THE TIME IT REACHES THE MIDSOUTH...IT MAY ENCOUNTER AN ATMOSPHERE AT LEAST SLIGHT WORKED OVER FROM CONVECTION THAT WILL OCCUR TODAY AND NOT AS UNSTABLE AS PREVIOUSLY THOUGHT A FEW DAYS AGO DUE TO CLOUD COVER. CAPE VALUES MAY GET TO 1500 J/KG WHICH IS STILL DECENT BUT NOT LIKE 2200 J/KG OR GREATER THAT THE NAM HAS BEEN SHOWING. MODELS ALSO CONTINUE TO BE A LITTLE SLOWER WITH TIMING. LINE MAY NOT GET INTO NORTHEAST ARKANSAS UNTIL CLOSER TO 9-10 PM. THUS INSTABILITY WILL BE WANING FROM LOSS OF DAYTIME HEATING. STILL EXPECT EASTERN ARKANSAS AND THE MISSOURI BOOTHEEL TO SEE THE BEST CHANCE OF SEEING SEVERE STORMS BUT REALLY EXPECT LINE TO START WEAKENING AS IT PUSHES EAST ESPECIALLY ONCE IT PUSHES EAST OF THE MISSISSIPPI RIVER. MAIN THREAT FROM THE LINE WILL BE DAMAGING WINDS AND LARGE HAIL. SINCE TIMING IS SLOWER HAVE HAD TO UPDATE POPS FOR FRIDAY TO KEEP THEM IN LONGER. NORTH MISSISSIPPI COULD SEE SOME REDEVELOPMENT OF THUNDERSTORMS ALONG THE FRONT DURING THE AFTERNOON HOURS. WOULD NOT BE SURPRISED IF SOME OF THESE BECAME STRONG WITH GUSTY WINDS AND SMALL HAIL. HIGH PRESSURE WILL BUILD INTO THE MIDSOUTH FOR THE WEEKEND AND WILL BRING BEAUTIFUL AUTUMN TEMPERATURES. HIGHS ON SATURDAY WILL BE IN THE MID TO UPPER 60S. LOWS SATURDAY NIGHT WILL DROP DOWN INTO THE UPPER 30S TO MID 40S. TEMPERATURES WILL JUMP BACK INTO THE 70S ON SUNDAY AS THE HIGH SHIFTS EAST. MODELS STILL DIFFER ON TIMING OF THE NEXT COLD FRONT FOR EARLY NEXT WEEK. THE ECMWF INDICATES FRONT WILL COME THROUGH SUNDAY NIGHT THROUGH MONDAY NIGHT. GFS HAS TIMING OF MONDAY NIGHT INTO TUESDAY. FOR NOW HAVE LEFT POPS AS IS WITH SMALL CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MONDAY INTO TUESDAY. DON/T REALLY EXPECT ANY COOL DOWN BEHIND THE FRONT AS AN UPPER RIDGE WILL BEGIN TO BUILD INTO THE AREA BEHIND IT. TEMPERATURES WILL LIKELY BE BACK INTO THE 80S BY WEDNESDAY. KRM && .AVIATION...12Z TAF CYCLE SHOWERS ARE ALREADY DEVELOPING ACROSS PORTIONS OF THE MIDSOUTH WITH NUMEROUS SHOWERS AND THUNDERSTORMS EXPECTED TO IMPACT ALL TAF SITES THIS AFTERNOON AND OVERNIGHT. PREVAILING CONDITIONS SHOULD INCLUDE OCCASIONAL MVFR CEILINGS SPREADING INTO THE REGION FROM THE SOUTHWEST BETWEEN 02/13Z AND 02Z/17Z ALONG WITH SCATTERED SHOWERS. AFTER 02Z/17Z CEILINGS LIFTING TO VFR BUT SCATTERED THUNDERSTORMS DEVELOPING. THUNDERSTORMS BECOMING MORE NUMEROUS AFTER 03/03Z AS A STRONG COLD FRONT APPROACHES FROM THE WEST. IFR OR LIFR CONDITIONS DUE TO HEAVY RAIN ALONG WITH GUSTY WINDS CAN BE EXPECTED IN ASSOCIATION WITH THUNDERSTORMS WINDS S-SW INCREASING TO 10-15 KTS WITH GUSTS TO NEAR 22 KTS AT KJBR. WINDS AFTER 03/00Z S 7-10 KTS. WINDS WILL SHIFT FROM THE WEST TO NORTHWEST BEHIND THE FRONT. TIMING IS QUESTIONABLE BUT JBR MAY SHIFT 03/08Z MEM 03/09Z...AND MKL 03/10Z. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS FORT WORTH TX
1028 AM CDT THU OCT 2 2014 .AVIATION... HRRR AND RAP ARE NOW SHOWING SCATTERED CONVECTION BREAKING OUT AROUND NOON IN METROPLEX AREA. COVERAGE WILL BE LOW WITH THESE DISCRETE CELLS BUT HAVE ADDED VCTS AFTER 17Z. AS I WRITE THIS WE HAVE ONE CELL IN DENTON COUNTY THAT NOW HAS CLOUD-CLOUD LIGHTNING...AND ONE IN HOOD COUNTY THAT VERTICAL INTEGRATED ICE IS SHOWING COMING CLOSE TO HAVING LIGHTNING. BEST CHANCE FOR TSRA STILL AHEAD OF THE FRONT LASTING FROM 20Z-22Z. 84 && .PREV DISCUSSION... /ISSUED 331 AM CDT THU OCT 2 2014/ WATER VAPOR LOOP SHOWS A PRONOUNCED SHORTWAVE TROUGH OVER NEW MEXICO RAPIDLY MOVING EASTWARD TOWARD THE REGION. FORCING FOR ASCENT AHEAD OF THIS FEATURE IS ALREADY REACHING THE REGION...AS AIRCRAFT DATA INDICATES LIFTING AND DYNAMIC COOLING OF THE MID LEVEL TEMPERATURE PROFILE. WHERE ENOUGH MOISTURE EXISTS ALOFT...ACROSS THE NW ZONES AND OKLAHOMA...THIS LIFT IS ALLOWING ELEVATED PARCELS TO REACH THEIR LFC AND CONVECT. THIS SCATTERED ELEVATED CONVECTION WILL REMAIN PRIMARILY NORTH OF THE REGION THIS MORNING...BUT THE NORTHWEST AND NORTHERN ZONES WILL HAVE A CHANCE OF MORNING SHOWERS OR STORMS. THE COLD FRONT IS NOW ENTERING THE TEXAS PANHANDLE AND IS FORECAST TO REACH THE NW ZONES BY MIDDAY. MODEL GUIDANCE IS AN HOUR OR TWO FASTER WITH THE FRONT...BUT OVERALL THERE IS LITTLE CHANGE TO THE FORECAST THINKING OF THE LAST FEW DAYS. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST WINDS OF 10 TO 20 MPH WILL ENSURE A WARM MORNING AND ONCE THE LOW STRATUS SCATTERS OUT BY MIDDAY...SUNSHINE WILL BOOST TEMPS INTO THE LOW TO MID 90S OVER THE REGION. THESE HOT TEMPS AND DEWPOINTS NEAR 70 OCCURRING IN CONJUNCTION WITH DYNAMIC COOLING ALOFT WILL RESULT IN A MODERATELY UNSTABLE AIRMASS DEVELOPING THIS AFTERNOON WITH CAPE REACHING 2000-2500 J/KG. WHILE A FAIRLY STRONG INVERSION NEAR 850MB WILL CAP OFF CONVECTIVE POTENTIAL EARLY IN THE DAY...THE COMBINATION OF DYNAMIC LIFT AHEAD OF THE SHORTWAVE TROUGH...CONVERGENCE ALONG THE FRONT...AND AFTERNOON HEATING WILL ALL WORK TO ERODE CONVECTIVE INHIBITION OVER THE AREA. SURFACE BASED CONVECTION IS EXPECTED TO FORM ALONG THE FRONT OVER THE NW ZONES AROUND 1 PM AS THE CAP BEGINS TO BREAK. CONVECTION WILL CONTINUE TO DEVELOP SOUTHWARD ALONG THE FRONT THROUGH THE MID-LATE AFTERNOON HOURS AS IT MARCHES SOUTHEAST INTO THE CENTRAL ZONES. WE EXPECT FROPA AROUND 3 PM NEAR GAINESVILLE...5 PM NEAR DFW...AND 7PM NEAR WACO. WHEN THE FRONT CROSSES THE I-35 CORRIDOR A SQUALL LINE WILL BEGIN TO TAKE SHAPE...WHICH MEANS THERE MAY STILL BE A FEW GAPS IN THE LINE AT THIS TIME. A FULLY DEVELOPED AND MATURE SQUALL LINE WILL EXIST AS THE FRONT MOVES EAST OF THE I-35 CORRIDOR EARLY THIS EVENING...AND IT APPEARS THE THREAT FOR DAMAGING WINDS IS HIGHEST IN THIS REGION. THE CAP WILL BE A LITTLE STRONGER OVER THE WESTERN AND SOUTHWESTERN ZONES...AND ACTIVITY WILL LIKELY BE MORE ISOLATED THERE. WHERE CONVECTION IS MORE ISOLATED...SUPERCELLULAR STORM MODE IS FAVORED...WHICH MEANS THERE IS AN ENHANCED LARGE HAIL THREAT IN ADDITION TO A WIND THREAT. WHILE LOW LEVEL WIND PROFILES DO NOT APPEAR FAVORABLE FOR LOW LEVEL ROTATION...SURFACE BASED SUPERCELLS CAN STILL PRODUCE ISOLATED TORNADOES GIVEN THE RIGHT MESOSCALE CONDITIONS...BUT THIS CANNOT BE FORECAST RELIABLY AT THIS TIME RANGE. THE FRONT AND LINE OF STORMS WILL RAPIDLY CLEAR THE REGION FROM NORTHWEST TO SOUTHEAST THIS EVENING. DRIER AND SLIGHTLY COOLER AIR WILL MOVE INTO THE REGION OVERNIGHT...BUT NORTHERLY WINDS WILL NOT REALLY INCREASE UNTIL FRIDAY WHEN A STRONGER HIGH PRESSURE SURGE ARRIVES. HIGHS FRIDAY WILL BE COOLER AND GENERALLY TOP OUT NEAR 80 IN THE NORTH AND THE MID 80S SOUTH. THE SURFACE HIGH WILL SETTLE IN RIGHT OVER THE CWA BY SUNRISE SATURDAY AND WINDS WILL GO CALM. WITH DEWPOINTS BY THIS TIME IN THE 30S AND 40S...LOWS SATURDAY MORNING SHOULD REACH THE 40S FOR A LARGE PORTION OF THE CWA...WITH LOW 50S FOR THE DFW AREA AND THE SOUTHEAST CWA. SATURDAY WILL BE SUNNY AND PLEASANT WITH HIGHS TOPPING OUT NEAR 80...BUT WINDS WILL SWITCH TO THE SOUTH BY SATURDAY EVENING. INCREASING MOISTURE AND A MODERATION OF TEMPS BACK ABOVE NORMAL WILL OCCUR SUNDAY INTO EARLY NEXT WEEK. THE 00Z ECMWF HAS AN OUTLIER SOLUTION OF A STRONG SHORTWAVE ROTATING THROUGH IN NORTHWEST FLOW ALOFT ON MONDAY WHICH BRINGS ANOTHER WEAK FRONT AND A CHANCE OF RAIN TO THE AREA. THE GFS/CANADIAN/UKMET ARE MUCH WEAKER WITH THIS ENERGY AND THEREFORE SHOW DRY WEATHER WITH HIGH TEMPS WARMING INTO THE 90S WITH LOWS IN THE 60S AND 70S. WILL KEEP FORECAST THE DRY BUT AS A NOD TO THE ECMWF POTENTIAL WILL NUDGE HIGH TEMPS DOWNWARD INTO THE MID TO UPPER 80S FOR NEXT WEEK INSTEAD OF THE CLIMATOLOGICALLY BOLD FORECAST OF LOWER 90S. TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 93 59 82 50 80 / 70 20 0 0 0 WACO, TX 95 58 84 49 81 / 50 40 5 0 0 PARIS, TX 91 57 78 45 76 / 80 60 0 0 0 DENTON, TX 92 54 81 43 80 / 60 10 0 0 0 MCKINNEY, TX 92 56 81 43 78 / 80 30 0 0 0 DALLAS, TX 93 60 82 51 80 / 70 30 0 0 0 TERRELL, TX 94 59 82 48 79 / 70 50 0 0 0 CORSICANA, TX 94 61 83 49 79 / 60 60 5 0 0 TEMPLE, TX 95 60 85 50 81 / 30 50 5 0 0 MINERAL WELLS, TX 92 54 82 44 81 / 30 10 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
955 AM CDT THU OCT 2 2014 .UPDATE...DENSE FOG THIS MORNING ISSUED AT 955 AM CDT THU OCT 2 2014 DENSE FOG ADVISORY HAS BEEN EXTENDED FOR SOUTHEAST MN AND BUFFALO COUNTY IN WISCONSIN AS CONDITIONS HAVE BEEN SLOW TO IMPROVE THIS MORNING. SOUNDINGS SHOW STEEP LOW LEVEL INVERSION CONTINUING THROUGH NOON AND WITH TROUGH AXIS RIGHT THROUGH THE REGION...LITTLE MIXING EXPECTED TO HELP BREAK THINGS UP. FOR NORTHEAST IOWA...OBSERVATIONS AND CALLS TO PARTNER GROUPS INDICATE THAT CONDITIONS HAVE IMPROVED SUCH THAT THE ADVISORY CAN BE ALLOWED TO EXPIRE. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 325 AM CDT THU OCT 2 2014 IMMEDIATE CONCERNS INCLUDE FOG THIS MORNING AND INCOMING RAIN. SURFACE MAP EARLY THIS MORNING HAS A WEAK TROUGH EXTENDING N-S ACROSS MN/IA. WEAKLY CONVERGENT AND VERY DAMP LOWER BOUNDARY LAYER HAS LED TO SOME AREAS OF DENSE FOG ACROSS PORTIONS OF NORTHEAST IA/SOUTHEAST MN AND WEST CENTRAL WI. AS A RESULT...A DENSE FOG ADVISORY IS IN EFFECT UNTIL 10 AM. OTHERWISE...WATER VAPOR AND RAP 500MB ANALYSIS SHOWING A DEEPENING LONG WAVE BASICALLY ALONG THE SPINE OF THE ROCKY MOUNTAINS. AT THE SURFACE...CYCLOGENESIS WAS TAKING PLACE OVER THE TX/OK PANHANDLE. LIFT AHEAD OF THIS TROUGH AND SURFACE LOW WAS PRODUCING SCATTERED SHOWERS AN THUNDERSTORMS ACROSS THE PLAINS/MID-MISSISSIPPI RIVER VALLEY REGION. OVER THE LOCAL AR X FORECAST AREA...BESIDES THE FOG...SKIES WERE MOSTLY CLOUDY WITH TEMPERATURES IN THE 50S TO THE LOWER 60S. FOR TODAY...WILL BE WATCHING THE LOW OVER THE TX/OK PANHANDLE LIFT NORTHEAST IN MO BY NOON AND NORTHERN IL BY EARLY THIS EVENING. AS THIS OCCURS...850 MB MOISTURE TRANSPORT/850-500MB FRONTOGENESIS AND ISENTROPIC LIFT WILL ALL COMBINE FORCES TO SPREAD SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA... BECOMING MORE WIDESPREAD IN THE AFTERNOON. OTHERWISE...EXPECT HIGHS TO TOP OFF IN THE MIDDLE 60S TO THE LOWER 70S. FOR TONIGHT...THE LOW WILL CONTINUE TO LIFT NORTHEAST ACROSS EASTERN WI. THIS PUTS ARX FORECAST AREA UNDER FAIRLY STRONG 850-500MB FRONTOGENETIC BAND IN THE 00-06Z TIME FRAME. THIS IS EXPECTED TO DRIVE WIDESPREAD MODERATE RAINFALL WITH AMOUNTS LIKELY RANGING FROM 1/4 TO 1/2 INCH. THEN AFTER MIDNIGHT...PLAN ON RAIN TAPERING OFF FROM WEST TO EAST AS THE LOW PULLS INTO EASTERN LAKE SUPERIOR. STRENGTHENING PRESSURE GRADIENT ACROSS THE AREA IN THE WAKE OF THE LOW WILL PRODUCE INCREASING NORTHWEST WINDS THROUGH THE OVERNIGHT HOURS. COLD AIR ADVECTION WILL DROP TEMPERATURES INTO THE MIDDLE 40S TO AROUND THE 50 DEGREE MARK. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 325 AM CDT THU OCT 2 2014 GUSTY NORTHWEST WINDS WILL OVERSPREAD THE AREA IN THE WAKE OF DEEPENING SURFACE LOW PULLING INTO EASTERN ONTARIO. PLAN ON SUSTAINED WIND SPEEDS IN THE 15 TO 25 MPH RANGE WITH GUSTS 25 TO 35 MPH. PV-ADVECTION ASSOCIATED WITH INCOMING MID-LEVEL LOW WILL ALSO PRODUCE A CHANCE OF SHOWERS MAINLY EAST OF THE MISSISSIPPI RIVER. COLDER TEMPERATURES/GUSTY NORTHWEST WINDS/RAIN SHOWERS WILL ALL COMBINE FOR A PRETTY RAW DAY. AS THE MID-LEVEL LOW ROTATES SOUTHEAST ACROSS THE AREA SATURDAY NIGHT...LOOKING FOR SCATTERED SHOWERS TO RESULT. AS TEMPERATURES COOL INTO THE MID/UPPER 30S LATER IN THE NIGHT...THERE IS THE POSSIBILITY OF A FEW SNOW FLAKES MIXING IN AT TIMES. RAIN SHOWERS WILL STILL BE POSSIBLE ON SATURDAY MAINLY EAST OF THE MISSISSIPPI RIVER IN COLD CYCLONIC FLOW. OTHERWISE...ANOTHER RAW AUTUMN DAY ON TAP AS HIGHS ONLY TOP OFF IN THE MIDDLE/UPPER 40S. CONTINUED COLD AIR ADVECTION SATURDAY NIGHT WILL DROP TEMPERATURES NEAR THE FREEZING MARK FOR A GOOD PART OF THE AREA. LONG WAVE TROUGH/CLOSED LOW WILL LINGER ACROSS THE REGION THROUGH MONDAY FOR BELOW NORMAL TEMPERATURES. AN EMBEDDED SHORTWAVE TROUGH LOOKS TO MAKE PASSAGE ACROSS THE AREA ON MONDAY FOR A CHANCE OF SHOWERS. OTHERWISE...PLAN ON HIGHS SUNDAY AND MONDAY IN THE MIDDLE 40S TO THE MIDDLE 50S WITH OVERNIGHT LOWS IN THE 30S. FOR TUESDAY AND WEDNESDAY...THE CLOSED LOW FILLS AND LIFTS NORTHEAST INTO CANADA WITH HEIGHTS BUILDING IN FROM THE WEST. THIS IS EXPECTED TO PRODUCE A SLOW MODERATION IN TEMPERATURES WITH HIGHS IN THE 50S/FEW LOWER 60S TUESDAY...AND IN THE 60S WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 630 AM CDT THU OCT 2 2014 A LOT OF CHALLENGES IN THE FORECAST THROUGH TONIGHT. FOR VSBYS...SUB 1/2SM FG HAS DEVELOPED ACROSS A PORTION OF MN/IA...BUT THERE HAS BEEN SOME FLUCTUATION IN THE VSBYS AS EVIDENCED BY OBSERVATIONS. FEEL IT WILL BE MORE 1/4SM THAN NOT AT KRST FOR THE EARLY MORNING...SO WILL STICK WITH THAT. GUIDANCE AND BUFKIT SOUNDINGS SUGGEST SOME IMPROVEMENT BY LATE MORNING...ALTHOUGH KRST MAY ONLY IMPROVE TO MVFR AT BEST. KLSE HAS AVOIDED THE LOWER VSBYS...ALTHOUGH OBSERVATIONS SURROUNDING THE SITE HAVE AT LEAST LOWERED TO MVFR. CONFIDENCE SHAKY WHEN/IF KLSE VSBYS WILL DROP. WILL LEAN ON THE TRENDS WHICH HAVE KEPT THEM MOSTLY P6SM. -SHRA WILL MOVE IN LATER TODAY...WITH MOST MESO MODELS SUGGESTING CLOSER TO 20Z. THEY ALSO WOULD TAKE THE PCPN EAST IN THE 04-06Z WINDOW. WILL USE THIS TIMING. A LOT OF CIGS IN THE LIFR/IFR CATEGORIES EARLY THIS MORNING...AND EXPECT ONLY SMALL DIURNAL IMPROVEMENT THROUGH THE DAY. DON/T SEE VFR RIGHT NOW...THOUGH COULD OCCUR LATER TONIGHT. AS THE SYSTEM MOVES OFF TO THE EAST RH FIELDS POINT TO A DECREASE IN THE SATURATION FOR A SHORT PERIOD OF TIME...WITH MORE MOISTURE ROLLING BACK IN FRIDAY. SEE SOME POTENTIAL FOR A FEW HOURS OF SCT CLOUDS...BUT WILL HOLD OFF ON THAT FOR NOW. WILL INSTEAD BUMP CIGS UP...ALTHOUGH KEEP KRST AT MVFR FOR THE MOMENT. A LOT OF COMPLEXITY TO THE FORECAST INTO TONIGHT. ANTICIPATE UPDATES. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR WIZ032. MN...DENSE FOG ADVISORY UNTIL NOON CDT TODAY FOR MNZ079-086>088-094- 095. IA...NONE. && $$ UPDATE...ZT SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
630 AM CDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 325 AM CDT THU OCT 2 2014 IMMEDIATE CONCERNS INCLUDE FOG THIS MORNING AND INCOMING RAIN. SURFACE MAP EARLY THIS MORNING HAS A WEAK TROUGH EXTENDING N-S ACROSS MN/IA. WEAKLY CONVERGENT AND VERY DAMP LOWER BOUNDARY LAYER HAS LED TO SOME AREAS OF DENSE FOG ACROSS PORTIONS OF NORTHEAST IA/SOUTHEAST MN AND WEST CENTRAL WI. AS A RESULT...A DENSE FOG ADVISORY IS IN EFFECT UNTIL 10 AM. OTHERWISE...WATER VAPOR AND RAP 500MB ANALYSIS SHOWING A DEEPENING LONG WAVE BASICALLY ALONG THE SPINE OF THE ROCKY MOUNTAINS. AT THE SURFACE...CYCLOGENESIS WAS TAKING PLACE OVER THE TX/OK PANHANDLE. LIFT AHEAD OF THIS TROUGH AND SURFACE LOW WAS PRODUCING SCATTERED SHOWERS AN THUNDERSTORMS ACROSS THE PLAINS/MID-MISSISSIPPI RIVER VALLEY REGION. OVER THE LOCAL AR X FORECAST AREA...BESIDES THE FOG...SKIES WERE MOSTLY CLOUDY WITH TEMPERATURES IN THE 50S TO THE LOWER 60S. FOR TODAY...WILL BE WATCHING THE LOW OVER THE TX/OK PANHANDLE LIFT NORTHEAST IN MO BY NOON AND NORTHERN IL BY EARLY THIS EVENING. AS THIS OCCURS...850 MB MOISTURE TRANSPORT/850-500MB FRONTOGENESIS AND ISENTROPIC LIFT WILL ALL COMBINE FORCES TO SPREAD SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA... BECOMING MORE WIDESPREAD IN THE AFTERNOON. OTHERWISE...EXPECT HIGHS TO TOP OFF IN THE MIDDLE 60S TO THE LOWER 70S. FOR TONIGHT...THE LOW WILL CONTINUE TO LIFT NORTHEAST ACROSS EASTERN WI. THIS PUTS ARX FORECAST AREA UNDER FAIRLY STRONG 850-500MB FRONTOGENETIC BAND IN THE 00-06Z TIME FRAME. THIS IS EXPECTED TO DRIVE WIDESPREAD MODERATE RAINFALL WITH AMOUNTS LIKELY RANGING FROM 1/4 TO 1/2 INCH. THEN AFTER MIDNIGHT...PLAN ON RAIN TAPERING OFF FROM WEST TO EAST AS THE LOW PULLS INTO EASTERN LAKE SUPERIOR. STRENGTHENING PRESSURE GRADIENT ACROSS THE AREA IN THE WAKE OF THE LOW WILL PRODUCE INCREASING NORTHWEST WINDS THROUGH THE OVERNIGHT HOURS. COLD AIR ADVECTION WILL DROP TEMPERATURES INTO THE MIDDLE 40S TO AROUND THE 50 DEGREE MARK. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 325 AM CDT THU OCT 2 2014 GUSTY NORTHWEST WINDS WILL OVERSPREAD THE AREA IN THE WAKE OF DEEPENING SURFACE LOW PULLING INTO EASTERN ONTARIO. PLAN ON SUSTAINED WIND SPEEDS IN THE 15 TO 25 MPH RANGE WITH GUSTS 25 TO 35 MPH. PV-ADVECTION ASSOCIATED WITH INCOMING MID-LEVEL LOW WILL ALSO PRODUCE A CHANCE OF SHOWERS MAINLY EAST OF THE MISSISSIPPI RIVER. COLDER TEMPERATURES/GUSTY NORTHWEST WINDS/RAIN SHOWERS WILL ALL COMBINE FOR A PRETTY RAW DAY. AS THE MID-LEVEL LOW ROTATES SOUTHEAST ACROSS THE AREA SATURDAY NIGHT...LOOKING FOR SCATTERED SHOWERS TO RESULT. AS TEMPERATURES COOL INTO THE MID/UPPER 30S LATER IN THE NIGHT...THERE IS THE POSSIBILITY OF A FEW SNOW FLAKES MIXING IN AT TIMES. RAIN SHOWERS WILL STILL BE POSSIBLE ON SATURDAY MAINLY EAST OF THE MISSISSIPPI RIVER IN COLD CYCLONIC FLOW. OTHERWISE...ANOTHER RAW AUTUMN DAY ON TAP AS HIGHS ONLY TOP OFF IN THE MIDDLE/UPPER 40S. CONTINUED COLD AIR ADVECTION SATURDAY NIGHT WILL DROP TEMPERATURES NEAR THE FREEZING MARK FOR A GOOD PART OF THE AREA. LONG WAVE TROUGH/CLOSED LOW WILL LINGER ACROSS THE REGION THROUGH MONDAY FOR BELOW NORMAL TEMPERATURES. AN EMBEDDED SHORTWAVE TROUGH LOOKS TO MAKE PASSAGE ACROSS THE AREA ON MONDAY FOR A CHANCE OF SHOWERS. OTHERWISE...PLAN ON HIGHS SUNDAY AND MONDAY IN THE MIDDLE 40S TO THE MIDDLE 50S WITH OVERNIGHT LOWS IN THE 30S. FOR TUESDAY AND WEDNESDAY...THE CLOSED LOW FILLS AND LIFTS NORTHEAST INTO CANADA WITH HEIGHTS BUILDING IN FROM THE WEST. THIS IS EXPECTED TO PRODUCE A SLOW MODERATION IN TEMPERATURES WITH HIGHS IN THE 50S/FEW LOWER 60S TUESDAY...AND IN THE 60S WEDNESDAY. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z FRIDAY MORNING) ISSUED AT 630 AM CDT THU OCT 2 2014 A LOT OF CHALLENGES IN THE FORECAST THROUGH TONIGHT. FOR VSBYS...SUB 1/2SM FG HAS DEVELOPED ACROSS A PORTION OF MN/IA...BUT THERE HAS BEEN SOME FLUCTUATION IN THE VSBYS AS EVIDENCED BY OBSERVATIONS. FEEL IT WILL BE MORE 1/4SM THAN NOT AT KRST FOR THE EARLY MORNING...SO WILL STICK WITH THAT. GUIDANCE AND BUFKIT SOUNDINGS SUGGEST SOME IMPROVEMENT BY LATE MORNING...ALTHOUGH KRST MAY ONLY IMPROVE TO MVFR AT BEST. KLSE HAS AVOIDED THE LOWER VSBYS...ALTHOUGH OBSERVATIONS SURROUNDING THE SITE HAVE AT LEAST LOWERED TO MVFR. CONFIDENCE SHAKY WHEN/IF KLSE VSBYS WILL DROP. WILL LEAN ON THE TRENDS WHICH HAVE KEPT THEM MOSTLY P6SM. -SHRA WILL MOVE IN LATER TODAY...WITH MOST MESO MODELS SUGGESTING CLOSER TO 20Z. THEY ALSO WOULD TAKE THE PCPN EAST IN THE 04-06Z WINDOW. WILL USE THIS TIMING. A LOT OF CIGS IN THE LIFR/IFR CATEGORIES EARLY THIS MORNING...AND EXPECT ONLY SMALL DIURNAL IMPROVEMENT THROUGH THE DAY. DON/T SEE VFR RIGHT NOW...THOUGH COULD OCCUR LATER TONIGHT. AS THE SYSTEM MOVES OFF TO THE EAST RH FIELDS POINT TO A DECREASE IN THE SATURATION FOR A SHORT PERIOD OF TIME...WITH MORE MOISTURE ROLLING BACK IN FRIDAY. SEE SOME POTENTIAL FOR A FEW HOURS OF SCT CLOUDS...BUT WILL HOLD OFF ON THAT FOR NOW. WILL INSTEAD BUMP CIGS UP...ALTHOUGH KEEP KRST AT MVFR FOR THE MOMENT. A LOT OF COMPLEXITY TO THE FORECAST INTO TONIGHT. ANTICIPATE UPDATES. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...DENSE FOG ADVISORY UNTIL 10 AM CDT FOR WIZ032. MN...DENSE FOG ADVISORY UNTIL 10 AM CDT FOR MNZ079-086>088- 094-095. IA...DENSE FOG ADVISORY UNTIL 10 AM CDT FOR IAZ008-009-018- 019. && $$ SHORT TERM...DAS LONG TERM....DAS AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS NEW YORK NY
129 PM EDT THU OCT 2 2014 .SYNOPSIS... AN UPPER LEVEL LOW WILL SLOWLY MOVE EAST TODAY...WITH HIGH PRESSURE BUILDING BRIEFLY IN ITS WAKE THROUGH FRIDAY. A COLD FRONT WILL PASS ON SATURDAY...FOLLOWED BY HIGH PRESSURE FOR SUNDAY AND MONDAY. WEAK LOW PRESSURE WILL AFFECT THE REGION ON TUESDAY...WITH A WEAK COLD FRONTAL PASSAGE LATE AT NIGHT. HIGH PRESSURE WILL RETURN ON WEDNESDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... FCST ADJUSTED TO CURRENT OBSERVATION AND TRENDS. RAIN CONFINED TO THE TWIN FORKS OF LONG ISLAND DRIFTING WEST SOUTHWEST. ELSEWHERE IT`S DRY WITH SOME SPOTTY DRIZZLE. THUS HAVE INCREASED POPS FOR EASTERN LONG ISLAND AND REMOVED POPS ELSEWHERE. LATEST HRRR SUPPORTS THE IDEA THAT PCPN DISSIPATES BY LATE MORNING. THUS HAVE RAPIDLY LOWERED POPS FOR EASTERN LONG ISLAND. OTHERWISE...UPPER LEVEL LOW SLOWLY PIVOTING THROUGH THE NORTHEAST. ASSOCIATED VORT MAX ALMOST STATIONARY OVER SOUTHERN NEW ENGLAND...WITH THE 00Z MODELS SUGGESTING IT PUSHING TO THE SOUTH THIS MORNING...THEN PUSHING OFFSHORE TO THE EAST AS THE LOW SLIPS TO THE EAST THROUGHOUT THE DAY. NE FLOW WILL KEEP A FAIRLY MOIST LOWER LEVEL IN PLACE BUT GENERALLY THINKING THE LOSS OF FORCING ALOFT WILL MINIMIZE THE PCPN CHANCES. SOME UNCERTAINTY WITH HIGH TEMPS FOR TONIGHT AS WEAK WAA WOULD SUGGEST TEMPS COULD PUSH NEAR NORMAL. HOWEVER...CLOUDY SKIES AND PERSISTENT NE FLOW COULD KEEP TEMPS ON THE SLIGHTLY COOLER SIDE. SIDED MORE WITH THE MAV GUIDANCE TO REFLECT THIS POSSIBILITY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... ANY LINGERING PCPN BY THIS EVENING SHOULD BE OFFSHORE SOUTH OF LONG ISLAND WITH DRY WX THEN ON TAP THROUGH FRIDAY. A SLIVER OF HIGH PRESSURE BRIEFLY BUILDS SOUTH FROM CANADA TONIGHT/FRIDAY BEFORE RETREATING ONCE AGAIN AHEAD OF AN APPROACHING LOW PRESSURE SYSTEM FOR THE WEEKEND. UPPER LEVEL RIDGING BUILDS IN AS WELL DURING THIS TIME...WITH THE RIDGE AXIS SHIFTING THROUGH THE NORTHEAST DURING THE DAY FRIDAY. PLENTY OF SUBSIDENCE ALOFT...SO SHOULD SEE CLEARING SKIES FOR A SHORT PERIOD LATE TONIGHT/FRIDAY MORNING BEFORE HIGH LEVEL CLOUDS BEGIN STREAMING IN AHEAD OF THE LOW. WITH DRIER AIR MOVING IN WITH THE HIGH AS WELL...NOT ANTICIPATING MUCH IN THE FORM OF FOG DEVELOPMENT TONIGHT. HAVE MORE OF A HANDLE ON TEMPS FOR TONIGHT/TOMORROW...USING GENERALLY A BLEND OF THE MET/MAV GUIDANCE. TEMPS TONIGHT EXPECTED TO BE RIGHT AROUND NORMAL TO SLIGHTLY ABOVE. WITH MOSTLY SUNNY SKIES ON FRIDAY AND WAA...SHOULD SEE HIGHS A FEW DEGREES WARMER THAN TODAY. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... ALL NWP GUIDANCE REMAINS VERY CONSISTENT WITH A COLD FROPA ON SATURDAY. PCPN MOVES IN FROM WEST TO EAST IN THE MORNING AND EXITS IN THE AFTN WITH CLEARING QUICKLY DEVELOPING BY SATURDAY EVENING. HAVE CUT PREVIOUS FORECAST QPF IN COORDINATION WITH RIVER FORECAST CENTERS. EXPECTING AROUND 1/2 INCH WITH 3/4 INCH UP IN THE LOWER HUDSON VALLEY. NO HYDRO ISSUES EXPECTED. HIGH PRESSURE FOR SUNDAY AND MONDAY. CLOUDS START INCREASING LATE MONDAY WITH WAA. OVER-RUNNING PATTERN CONTINUES ON TUES WITH CHC POPS FOR LGT RA. WEAK AND DIFFUSE COLD FROPA PASSAGE EARLY WEDNESDAY MORNING WITH HIGH PRESSURE BUILDING IN. HAVE MADE IT DRY ON WEDNESDAY WITH TIMING OF COLD FROPA. LOWERED TEMPS AND MADE FOR NON-DIURNAL PATTERN ON SATURDAY WITH THE PCPN. BELOW NORMAL TEMPS ON SUNDAY...BUT WE QUICKLY RETURN TO NORMAL ON MONDAY AND THEN A BIT ABOVE NORMAL FOR TUESDAY AND WEDNESDAY. NO HAZARDS FORESEEN THROUGH WEDNESDAY. && .AVIATION /15Z THURSDAY THROUGH MONDAY/... LOW PRESSURE WELL EAST OF CAPE COD WILL REMAIN NEARLY STATIONARY TODAY...WITH HIGH PRESSURE BUILDING OVER THE TERMINALS THROUGH FRIDAY MORNING. MVFR CIGS WILL BEGIN TO LIFT TO VFR AFTER 19Z FROM NORTHWEST TO SOUTHEAST. VFR CONDS THEREAFTER WITH N-NE FLOW 10 TO 15 KT. WINDS VEER TO THE E AND POSSIBLY SE OVER CITY TERMINALS THIS EVENING BEFORE BACKING TO THE NE AFTER MIDNIGHT. SPEEDS BECOME LIGHT OVERNIGHT. ...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: TIMING OF IMPROVEMENT TO VFR AND WIND SHIFT TO THE E COULD BE OFF BY +/- AN HOUR OR TWO. KLGA FCSTER COMMENTS: TIMING OF IMPROVEMENT TO VFR AND WIND SHIFT TO THE ESE COULD BE OFF BY +/- AN HOUR OR TWO. KEWR FCSTER COMMENTS: TIMING OF IMPROVEMENT TO VFR AND WIND SHIFT TO THE ESE COULD BE OFF BY +/- AN HOUR OR TWO. KTEB FCSTER COMMENTS: CIGS MAY FLUCTUATE BETWEEN VFR AND MVFR UNTIL 20Z. KHPN FCSTER COMMENTS: CIGS MAY FLUCTUATE BETWEEN VFR AND MVFR UNTIL 20Z. KISP FCSTER COMMENTS: TIMING OF IMPROVEMENT TO VFR COULD BE OFF BY +/- AN HOUR OR TWO. .OUTLOOK FOR 18Z FRI THROUGH TUE... .FRI...VFR. .FRI NIGHT...MVFR CONDS POSSIBLE LATE AT THE NYC METRO AND LOWER HUDSON VALLEY TERMINALS. .SAT...RAIN WITH IFR CONDS AND SE WINDS 15-20G25KT FOLLOWED BY VFR CONDS AND W WIND G20KT LATE. .SAT NIGHT...W WINDS G25KT. .SUNDAY...VFR. W WINDS G20KT. .MON-TUE...VFR. && .MARINE... MINIMAL SCA REMAINS IN EFFECT FOR ALL THE WATERS LESS THE GREAT SOUTH BAY...NY HARBOR AND THE WESTERN SOUND AS NE FLOW INCREASES BETWEEN THE LOW OFFSHORE AND THE HIGH DIGGING DOWN FROM THE NORTH. GUSTS BETWEEN 23 TO 28 KT EXPECTED DURING THE DAY TODAY...THEN DIMINISHING TONIGHT AS THE PRESSURE GRADIENT WEAKENS WITH HIGH BUILDING FURTHER OVER THE WATERS. SEAS BUILD TODAY WITH THE STRENGTHENING FLOW...WITH 5-9 FT POSSIBLE ON THE OCEAN WATERS. OCNL GUSTS UP TO 25 KT WILL BE POSSIBLE THIS EVENING/EARLY OVERNIGHT FOR THE BAYS AND LONG ISLAND SOUND. THOUGH CONFIDENCE IS NOT ENOUGH TO EXTEND THE SCA AT THIS TIME OVER THOSE WATERS. STILL EXPECTING GUSTS TO 25 KT AND SEAS ABOVE 5 FT ON THE OCEAN...AND IN FACT EXPECTING THE 5 FT SEAS TO CONTINUE SO EXTENDED THE SCA OVER THE OCEAN FOR FRIDAY. ON THE OCEAN...SCA CONDS CAN BE EXPECTED THRU NEXT WED...WITH PERHAPS A BRIEF RESPITE FOR PORTIONS OF MON. ELSEWHERE...25KT WINDS POSSIBLE SAT-SUN BOTH AHEAD OF AND BEHIND A CDFNT. OTHERWISE THEY WILL GENERALLY BE IN THE 10-20KT RANGE. && .HYDROLOGY... NO SIGNIFICANT PRECIPITATION IS EXPECTED THROUGH FRI EVENING. EXPECTING AROUND 1/2 INCH WITH 3/4 UP IN THE LOWER HUDSON VALLEY DURING THE DAY ON SATURDAY. LIGHT RAIN IS POSSIBLE FOR TUESDAY. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. NJ...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT FRIDAY FOR ANZ350-353-355. SMALL CRAFT ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ330- 340. && $$ SYNOPSIS...MALOIT/SEARS/TONGUE NEAR TERM...MALOIT/SEARS/TONGUE SHORT TERM...SEARS LONG TERM...TONGUE AVIATION...DS MARINE...SEARS/TONGUE HYDROLOGY...SEARS/TONGUE
AREA FORECAST DISCUSSION
NWS MIAMI FL
200 PM EDT THU OCT 2 2014 .AVIATION... LIGHT WESTERLY WINDS CONTINUE ACROSS THE REGION. WITH THE EXCEPTION FOR TERMINAL KTMB...THE FORECAST STILL INCLUDES AN ATLANTIC COAST SEA BREEZE STARTING IN 19-20Z TIME FRAME FOR MOST EASTERN TERMINALS BUT NEED TO EMPHASIZE THE UNCERTAINTY. THE WESTERLY FLOW WILL STILL FAVOR INTERIOR PENINSULA AND ATLANTIC COASTAL ZONE SHOWERS/THUNDERSTORMS WITH ALL EASTERN TERMINALS ASSIGNED VCTS IN THE 19-20Z TIME FRAME AND BRIEF SUB-VFR CONDITIONS POSSIBLE WITH OCCURRENCE OF SHOWERS/THUNDERSTORMS. AT 00Z WINDS WILL BE SOMEWHAT LIGHT AND VARIABLE. 60 && .PREV DISCUSSION... /ISSUED 1035 AM EDT THU OCT 2 2014/ UPDATE... NO MAJOR UPDATES ARE ANTICIPATED THIS MORNING AS THE PREVIOUS FORECAST REMAINS ON TRACK. THE MORNING SURFACE ANALYSIS SHOWED A STALLED FRONTAL BOUNDARY EXTENDING WESTWARD ACROSS CENTRAL FLORIDA WITH MAINLY LIGHT WNW FLOW CONTINUING ACROSS SOUTH FLORIDA. THE LOW-LEVEL FLOW UP TO 700MB FROM THE MORNING UPPER AIR SOUNDING IN MIAMI WAS SLIGHTLY WEAKER THAN THE PAST FEW DAYS. THIS LOW-LEVEL FLOW COMBINED WITH DAYTIME HEATING SHOULD ALLOW THE EAST COAST SEA BREEZE TO SETUP THROUGH THE AFTERNOON HOURS AND BECOME MORE ESTABLISHED. THE LATEST HRRR MODEL RUN REFLECTS THIS PATTERN AND GENERALLY INDICATES THE BEST SHOWER AND THUNDERSTORM COVERAGE THIS AFTERNOON SETTING UP AND FOCUSING OVER BROWARD AND MIAMI-DADE COUNTIES. WEAK MID-LEVEL LAPSE RATES ALONG WITH FAIRLY WARM 500MB TEMPERATURES AND RISING UPPER HEIGHTS SHOULD KEEP THE THREAT OF STRONG TO SEVERE THUNDERSTORMS LOW TODAY. THE MAIN IMPACTS FROM THE STORMS THAT DO MANAGE TO DEVELOP WILL BE LIGHTNING AND 35 TO 45 MPH WIND GUSTS. 85 PREV DISCUSSION... /ISSUED 802 AM EDT THU OCT 2 2014/ AVIATION... REGIONAL OBSERVATIONS INDICATE THERE IS ISOLATED AREAS WITH LOW STRATUS AND/OR MIST ACROSS SOUTH FLORIDA...MAINLY IN THE VICINITY OF THE LAKE WITH CURRENT METAR OBS FROM KPBI INDICATING BRIEF PERIODS OF IFR CEILINGS POSSIBLE EARLY THIS MORNING. TERMINAL KTMB MAY HAVE VERY BRIEF PERIODS OF IFR VISIBILITY EARLY THIS MORNING. OTHERWISE...CHALLENGING WIND FORECAST. WEAK WESTERLY WINDS PREVAIL ACROSS THE REGION AND FORECAST TO BECOMING NORTHWESTERLY LATER THIS MORNING. AFTER 18Z THE WEST AND EAST COAST SEA BREEZES ARE EXPECTED TO FORM...BUT FOR TERMINALS KTMB AND KOPF WINDS COULD STAY LIGHT NORTHWESTERLY. LINGERING TROPICAL MOISTURE COULD FAVOR SHOWERS/THUNDERSTORMS THIS AFTERNOON...WITH WESTERLY WINDS FAVORING CONVECTION IN THE EASTERN HALF OF THE PENINSULA. ALL EAST COAST TERMINALS ASSIGNED VCTS IN THE 18Z TO 21Z TIME FRAME. 60 PREV DISCUSSION... /ISSUED 328 AM EDT THU OCT 2 2014/ TYPICAL AFTERNOON SCATTERED THUNDERSTORMS NEXT FEW DAYS... FIRST COLD FRONT OF FALL SEASON ARRIVES SATURDAY NIGHT... DISCUSSION...SURFACE RIDGE WILL REMAIN OVER THE FLORIDA STRAITS THROUGH FRIDAY, MAINTAINING A WESTERLY WIND FLOW. THIS WILL FOCUS SCATTERED THUNDERSTORMS OVER THE INTERIOR AND EAST COAST METRO AS AN ATLANTIC SEA BREEZE DEVELOPS DURING THE AFTERNOON. SOME DRIER AIR IN THE MID LEVELS IS EXPECTED TO KEEP CONVECTION SCATTERED THIS AFTERNOON AS WELL AS ON FRIDAY. THE MAIN IMPACTS FROM THE TSTORMS WILL BE LIGHTNING STRIKES AND BRIEF HEAVY RAINS. GFS AND ECMWF CONTINUE TO SHOW AN AMPLIFIED LONGWAVE TROUGH ACROSS THE EASTERN U.S. THIS WEEKEND, SENDING THE FIRST COLD FRONT OF THE SEASON ACROSS SOUTH FLORIDA SATURDAY NIGHT. SCATTERED CONVECTION IS EXPECTED AHEAD OF THE FRONT, BUT FORCING WILL BE TO THE NORTH SO ONLY ORDINARY STORMS ARE ONLY EXPECTED. THE BIG STORY WILL BE THE DROP IN DEWPOINTS AND A SLIGHT LOWERING OF TEMPERATURES TO MAKE A VERY NOTICEABLE CHANGE IN AIRMASS ACROSS SOUTH FLORIDA AFTER THE LONG STEAMY TIMES SINCE MAY. GUIDANCE TEMPS/POPS WERE NOT SIGNIFICANTLY CHANGED FROM THIS TIME YESTERDAY SO NO APPRECIABLE CHANGES ARE NOTED IN THE EXTENDED FORECAST. DRYING BEHIND THE FRONT WILL OCCUR SUN-MON, BUT MOISTURE LOOKS TO RETURN ON A RETURN FLOW BY TUE WITH INCREASING HUMIDITY AND A RETURN TO SCATTERED TSTORMS THEN. /GREGORIA MARINE...LIGHT WINDS AND LOW SEAS WILL CONTINUE BUT WINDS WILL PICK UP IN ASSOCIATION WITH THE FIRST COLD FRONT OF THE FALL SEASON EXPECTED TO MOVE ACROSS THE LOCAL WATERS SATURDAY NIGHT. AS WINDS TURN N THEN NE, SEAS WILL BUILD ESPECIALLY OFF THE PALM BEACH COAST BUT NWPS CURRENTLY KEEPS SEAS BELOW HAZARDOUS LEVELS, OR 7 FT. /GREGORIA && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 74 89 76 90 / 20 40 20 50 FORT LAUDERDALE 78 90 78 90 / 20 40 20 50 MIAMI 77 90 78 90 / 20 50 20 50 NAPLES 75 90 76 89 / 10 20 20 50 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...NONE. GM...NONE. && $$ SHORT TERM...60/BD LONG TERM....85/AG AVIATION...60/BD
AREA FORECAST DISCUSSION...UPDATED
NWS TALLAHASSEE FL
ISSUED BY NATIONAL WEATHER SERVICE MOBILE AL 1242 PM EDT Thu Oct 2 2014 .Short Term... Did a quick update to the current zone forecast mainly to expand the slight chance pops a little further to the east mostly over inland sections generally west of the Tallahassee and Apalachicola fl. Latest 12z runs from both the HRRR and Nam show a little better coverage in the these areas this afternoon and early this evening then previous expected. Current temps look close. && .Aviation... [Through 18Z Friday]...Expect mostly VFR to MVFR conditions for all terminal sites through 03.06z followed by MVFR to IFR cigs and visibilities for TLH, VLD, DHN, and ABY through about 03.13z with mainly MVFR cigs for ECP through 03.13z. Better low to mid clouds along with scattered to numerous showers and thunderstorms will develop by early Fri possible leading to MVFR to IFR conditions in and around the heavier precip for all terminal sites especially during the afternoon and evening hours. Easterly winds at 5 to 8 knots will shift southeast then south through 03/00z becoming south to southwest around 10 knots with higher gusts through 03.18z. && .Marine... Made little to no changes to the previous forecast. A light east to southeast wind today will shift mostly south to southwest and gradually build tonight and on Fri ahead of a cold front approaching from the northwest late Fri night through Sat morning. Expect higher winds and seas in and around scattered to numerous showers and thunderstorms beginning later tonight continuing through fri night ahead and along of the front. Expect Exercise Caution to possible Small Craft Conditions ahead and behind the front Fri night and on Sat. && .Prev Discussion [251 AM EDT]... .Near Term [Through Today]... An upper level shortwave trough over the four corners region is deepening the upper level trough over the western CONUS, with weak ridging still in place aloft over the Mississippi valley. At the surface, high pressure is still in place over the eastern CONUS, but will continue to slide eastward through the period as a developing front over the Plains begins to trek eastward. Today will be dry, with only a slight (20%) chance for showers in extreme western portions of our area. Highs will be quite warm for October- in the upper 80s to around 90. .Long Term [Saturday Night Through Thursday]... The ridge of high pressure behind the cold front will quickly build into the region on Saturday night and Sunday, and remain centered in our vicinity through Monday. While there will be significant cool air advection, the exact position of the ridge during the overnight hours will be critical for radiational cooling for both Sunday and Monday morning. At this time, the model guidance is continuing to trend cooler, with lows on Sunday expected to be in the middle to upper 40s over much of the interior, with upper 40s to lower 50s fcst for Monday morning. High temps will gradually moderate through the period, ranging from the middle to upper 70s on Sunday, to the lower to middle 80s on Wednesday. Rain chances will be very slim through the entire period, with just a slight chance of a shower on Monday night and Tuesday as an upper level disturbance moves through from the NW. .Fire Weather... Relative humidities will dip into the mid to upper 20s this weekend west of a line from Apalachicola to Fitzgerald in the wake of a cold front. At this time, it looks like Alabama will reach its relative humidity duration and 20-ft wind criteria and likely its KBDI values as well on Saturday. The Florida Panhandle and western Big Bend counties appear to be more borderline, with most of the Panhandle reaching duration criteria and much of both areas reaching wind criteria, but the ERC values are more uncertain as they will depend on how much rainfall we will accumulate. In Georgia, relative humidities are expected to remain above 25 percent, preventing red flag criteria from being reached there. Relative humidity will be low for long durations Sunday as well, but winds will be lower, preventing red flag conditions in Alabama. Depending on the ERC values, Florida may be borderline once again Sunday. .Hydrology... Although some of the stronger storms on Friday could produce locally heavy rainfall in excess of 2", most areas should receive average totals of 1" or less due to the fast moving nature of the approaching cold front. This amount of rainfall will have little impact on our area rivers and streams. && .PRELIMINARY POINT TEMPS/POPS... Tallahassee 90 70 88 64 80 / 10 10 60 60 10 Panama City 86 75 86 64 79 / 10 20 70 50 0 Dothan 89 70 84 56 74 / 10 20 70 40 0 Albany 89 68 87 59 76 / 10 10 70 50 0 Valdosta 88 67 87 64 77 / 10 10 60 60 20 Cross City 88 68 87 70 82 / 10 20 40 50 30 Apalachicola 85 74 85 67 80 / 10 10 60 60 10 && .TAE WATCHES/WARNINGS/ADVISORIES... FL...None. GA...None. AL...None. GM...None. && $$ NEAR TERM...MOORE SHORT TERM...EE LONG TERM...GOULD AVIATION...EE MARINE...EE FIRE WEATHER...MOORE HYDROLOGY...GOULD/WOOL
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
258 PM CDT THU OCT 2 2014 .DISCUSSION... 226 PM CDT MAIN FOCUS FOR THIS EVENING WILL BE ON POTENTIAL FOR THUNDERSTORMS...ALONG WITH A FEW STRONGER STORMS POSSIBLY IN THE FAR SOUTHEAST CWFA THIS EVENING. CONSIDERABLE CLOUD COVER HAS KEPT THE TEMPERATURES IN CHECK...WITH HIGHS THIS AFTN STRUGGLING TO WARM BEYOND 70 TO THE MID 70S SOUTH OF A PONTIAC TO VALPO LINE. VERY MOIST AIRMASS HAS PUMPED DEW POINTS INTO THE LOW/MID 60S THIS AFTN. THE INSTABILITY HAS BEEN STRUGGLING TO GET GOING THIS AFTN ACROSS THE BULK OF THE AREA...LARGELY DUE TO THE THICK SOLAR SHIELDING. AS THE LOW CONTINUES TO LIFT NORTHEAST TOWARDS NORTHWEST IL THIS EVE...THIS SHOULD HELP WITH CONVECTIVE INITIATION. HI-RES GUIDANCE HAS BEEN CONSISTENT WITH DEVELOPING A LINE SEGMENT...HOWEVER TRYING TO PIN-DOWN WHERE THIS LINE DEVELOPS IS THE LARGEST CHALLENGE. EITHER WAY...EXPECT A FEW EMBEDDED STORMS TO DEVELOP AND LIFT NORTH TOWARDS CHICAGO EARLY THIS EVE. GIVEN THE ANOMALOUSLY HIGH MOISTURE CONTENT WITHIN THE ATMOSPHERE...A FEW OF THESE STORMS COULD EASILY PRODUCE HEAVY DOWNPOURS. THE GREATEST SHEAR CONTINUES TO BE FOCUSED ALONG AND SOUTH OF GIBSON CITY TO VALPO LINE...SO ANY STRONGER STORMS THAT DEVELOP IN THAT AREA COULD SEE STRONG ASCENT AND POSSIBLY A ROTATING UPDRAFT. THUNDERSTORM ACTIVITY SHUD QUICKLY SHIFT TO THE EAST AS THE SFC LOW LIFTS NORTHEAST OF THE AREA...AND WINDS SHIFT WEST. 850MB THERMAL TROUGH WILL BE QUICKLY APPROACHING FROM THE WEST...HOWEVER WILL LIKELY NOT ARRIVE UNTIL AFT DAYBREAK FRI. LOW TEMPS WILL LIKELY REMAIN MILD...IN THE MID 50S TO LOW 60S. FRIDAY THROUGH SATURDAY... STRONG PRESSURE RISES ARE POISED TO ARRIVE FRI AS THE PUNCH OF MUCH COOLER AIR ARRIVES FROM THE WEST. TEMPS WILL LIKELY BE THE WARMEST AT SUNRISE...OR SHORTLY AFTER. BY EARLY AFTN EXPECT TEMPS TO BEGIN FALLING A FEW DEGREES INTO THE LOW 50S ACROSS THE NORTHWEST AND MID 50S IN THE SOUTHEAST. 500MB TROUGH AXIS WILL BE ARRIVING OVERHEAD MIDDAY FRI...WITH A PERIOD OF SOME LIGHT SHOWERS ARRIVING MIDDAY. WINDS WILL BE SHIFTING NORTHWEST AND WITH A TIGHT GRADIENT REMAINING THE GUSTY WINDS SHUD PERSIST THRU FRI NGT/SAT MORNING. CURRENTLY EXPECT SOME LIGHT SHOWERS TO ALSO PERSIST THRU SAT...HOWEVER COULD SEE DRY AIR ARRIVING SAT MORNING AND PERHAPS RESULT IN A DRY DAY. COLD AIR ADVECTION WILL CONTINUE ACROSS THE CWFA WITH HIGHS STRUGGLING TO MOVE BEYOND THE UPR 40S IN A FEW PLACES SAT...PERHAPS REACHING 50 SOUTH OF I-80. YES FOR HIGHS...WHICH IS APPROXIMATELY 15-20 DEGREES BELOW NORMAL. AT THIS TIME IT LOOKS LIKE ENOUGH WIND WILL LINGER SAT NIGHT TO PREVENT FROST FORMATION...SO HAVE HELD THIS OUT OF THE CURRENT FORECAST. BUT OVERNIGHT LOWS WILL AGAIN DIP INTO THE MID/UPR 30S. SUNDAY THROUGH THURSDAY... MAIN FEATURE IN THE EXTENDED CONTINUES TO FOCUS ON THE HIGH AMPLITUDE RIDGE ACROSS THE CANADIAN MARITIME/NORTH ATLANTIC...AS THE ENSEMBLES MAINTAIN THIS FEATURE THRU THE BULK OF THE EXTENDED. THIS WILL LIKELY RESULT IN THE PROLONGED TROUGHING ACROSS THE GREAT LAKES...AND CONTINUED UNSEASONABLY COOL AIR. CLOSER TO LATER IN THE WEEK GUIDANCE SUGGESTS THE STRENGTH OF THE BLOCK WILL BEGIN TO WEAKEN...HOWEVER SOME ELEMENTS OF TROUGHING ACROSS THE GREAT LAKE WILL CONTINUE. PERIODIC SHORTWAVES WILL SLIDE SOUTHEAST FROM CENTRAL CANADA AND BRING SOME LGT PRECIP IN THE EXTENDED...BUT NOT EXPECTING AT THIS TIME ANYTHING TOO SIGNIFICANT. BEACHLER && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 20Z... * SHOWERS AND SOME THUNDERSTORMS EXPECTED AFTER 22 TO 23 UTC THROUGH AROUND 04 TO 05 UTC THIS EVENING. PERIODS OF SHOWERS AND RAIN LIKELY PERSISTING OVERNIGHT. * IFR TO POSSIBLY LIFR CIGS LIKELY OVERNIGHT INTO FRIDAY MORNING. * WIND SHIFT TO THE WEST NORTHWEST FOLLOWING FROPA EARLY FRIDAY MORNING...WITH INCREASING SPEEDS DURING THE DAY. KJB //DISCUSSION...UPDATED 18Z... THE MAIN WEATHER CONCERNS CONTINUE TO REVOLVE AROUND THE CONVECTIVE ACTIVITY EXPECTED THE IMPACT THE TERMINALS BY EARLY THIS EVENING. PLENTY OF LOWER LEVEL MOISTURE HAS BEEN TRANSPORTED ACROSS THE AREA OUT AHEAD OF LOW PRESSURE CURRENTLY LOCATED ACROSS EASTERN KANSAS AND MISSOURI. THIS CONTINUES TO SUPPORT THE MVFR CIGS AROUND 2,000 FT AGL. NUMEROUS SHOWERS AND THUNDERSTORMS ALSO CONTINUE TO BUILD EAST NORTHEASTWARD ACROSS MISSOURI AND INTO WEST CENTRAL ILLINOIS. THIS ACTIVITY WILL APPROACH THE TERMINALS LATER THIS AFTERNOON AFTER 21-22 UTC. IT STILL APPEARS THE BEST CHANCES FOR THUNDERSTORMS WILL BE THROUGH MID TO LATE THIS EVENING...WITH PERIODS OF MODERATE TO HEAVY RAINFALL POSSIBLE AT TIMES. PERIODS OF MODERATE RAIN AND IFR TO LIFR CIGS ARE EXPECTED OVERNIGHT FOLLOWING THE THUNDERSTORM THREAT THIS EVENING. A SURFACE COLD FRONT SHOULD SHIFT OVER THE TERMINALS AROUND DAYBREAK FRIDAY...WITH A WIND SHIFT OUT OF THE WEST-NORTHWEST. CIGS SHOULD IMPROVE DURING THE MORNING...BUT GUSTY WEST-NORTHWEST WINDS OF 20 TO 25 KT ARE EXPECTED FOR MUCH OF THE DAY FRIDAY. KJB //ORD AND MDW CONFIDENCE...UPDATED 20Z... * MEDIUM-HIGH WITH WIND SPEED/DURATION. * MEDIUM-HIGH WITH SHOWERS/THUNDERSTORMS...MEDIUM ON TIMING. * MEDIUM-HIGH WITH IFR CIGS TONIGHT...LOW-MEDIUM WITH LIFR. KJB //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...CHANCE OF SHRA. SATURDAY...CHANCE OF SHRA. SUNDAY...SLIGHT CHANCE OF SHRA. MONDAY...CHANCE OF SHRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 1249 PM CDT MAIN MARINE FORECAST CONCERN IS WITH THE POTENTIAL FOR A PERIOD OF WESTERLY GALES FRIDAY AFTERNOON INTO SATURDAY MORNING...MAINLY ACROSS THE CENTRAL AND SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE OVER THE MID-MISSOURI VALLEY EARLY THIS AFTERNOON IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST INTO SOUTHWESTERN WISCONSIN BY EARLY THIS EVENING...AND TO EASTERN LAKE SUPERIOR BY FRIDAY MORNING. IN THE PROCESS...A SHARP COLD FRONT WILL TRAIL ACROSS LAKE MICHIGAN OVERNIGHT...WITH WINDS SHIFTING TO THE WEST BEHIND THE FRONT. A COMBINATION OF MUCH COOLER AIR AND THE TIGHTENING OF THE SURFACE PRESSURE GRADIENT BETWEEN THE DEEPENING LOW AND HIGH PRESSURE BUILDING SOUTH ACROSS THE NORTHERN HIGH PLAINS WILL RESULT IN GUSTY WESTERLY WINDS...WITH FORECAST SOUNDINGS SUPPORTING A PERIOD OF 35 KT GALES DEVELOPING BY EARLY FRIDAY AFTERNOON AND CONTINUING INTO EARLY SATURDAY. A SECONDARY SURFACE TROUGH WILL MAINTAIN THE COOL ADVECTION ACROSS THE LAKE THROUGH THE DAY SATURDAY WITH WINDS SLOWLY EASING TO 25-30 KT SATURDAY NIGHT. DEEP LOW PRESSURE IS FORECAST TO REMAIN NORTH OF THE LAKES ACROSS FAR NORTHWEST ONTARIO AND JAMES BAY THROUGH SUNDAY...WITH SOME WEAKENING OF THE SURFACE PRESSURE GRADIENT OVER THE OHIO VALLEY AND SOUTHERN LAKES AS ANOTHER WEAKER LOW MOVES THROUGH THE REGION. THIS LOOKS TO KEEP WEST-SOUTHWEST WINDS AT/ABOVE 20 KT INTO SUNDAY. GUSTY WEST WINDS WILL LIKELY SUPPORT SMALL CRAFT ADVISORY CONDITIONS OVER THE ILLINOIS NEAR SHORE ZONES...WITH GALE FORCE GUSTS LATE FRIDAY AND FRIDAY NIGHT FARTHER EAST ALONG THE INDIANA SHORE. RATZER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WATCH...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744- LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876- LMZ878...4 PM FRIDAY TO 9 AM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
  [top] Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 246 PM CDT Thu Oct 2 2014 .SHORT TERM...(Tonight) ISSUED AT 246 PM CDT THU OCT 2 2014 Two concerns with this part of the forecast are the severe weather and flash flood potential. Early afternoon radar imagery showing an increase in showers and thunderstorms along and east of I-57. Areas southeast of I-70 have had some breaks in the cloud cover, which has allowed CAPE`s to rise to over 2000 J/kg. While the late morning severe weather outlook covers the entire CWA, it is looking like areas south of I-72 will be the main concern. Additional line of storms moving through south central Missouri will be entering our forecast area very late afternoon or early evening per the HRRR model. The high-res models are also showing some convection along the front itself, which will be entering the western CWA toward midnight and crossing the CWA overnight. Forecast soundings are rather moist through 10kft, so think that damaging winds and intense lightning will be more of a concern than large hail. In regards to the flood threat, the overnight rainfall deposited from 2.5 to 4 inches along the southwest edge of the CWA as far east as Taylorville, with more isolated streaks of 2+ inches near Mattoon. Precipitable water values expected to be around 1.8 to 1.9 inches, which is about 3 standard deviations above normal for early October. Another couple inches potentially may occur through tonight, especially across the southwest CWA. Will leave the flash flood watch in its current configuration. && .LONG TERM...(Friday through Thursday) ISSUED AT 246 PM CDT THU OCT 2 2014 By Friday morning, the front will be through the area and any pcpn will be in the form of showers and should only be in the eastern parts of the CWA. So, early Friday pops will just be high chance and then decrease during the day. However, with the upper level trough still west of the area, any clearing behind the front will allow cold air clouds and scattered showers to develop and spread across the area for Friday afternoon. Will have slight chance pops in the forecast for this type of pcpn. Once the trough rotates through, the upper level cold low pressure area will drop into the Grt Lks and bring continued daytime/diurnal clouds in the area for Sat and Sun. Any pcpn associated with this will be very light, primarily be over northeast IL, and not worth the mention at this time. Temps will become cooler the end of the week and into the weekend, after the front moves through. 850mb temps forecast to be around -2 to -4 for the weekend, so coldest temps look to be Fri night through Sat night. Would not be surprised to see some frost in some areas in the northwest Sat night, if clouds can clear out and winds become lighter. Cyclonic flow will remain over the area into the beginning of next week, but not quite as deep as it is for this weekend. That being said, the models do forecast another frontal system to move into the area Sunday night and remain in the area through Monday night. So, a chance of pcpn will continue over the area through that time period. Past Monday night, any pcpn chances will be small, in the 20pct range. This will only be seen in the grids, with nothing mentioned in the worded forecast. So, unsettled pattern looks to take hold for most of the week. Temps through the extended will remain on the cool side, but as the pattern becomes more zonal, there should be a slight warming trend for the later part of the week. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1226 PM CDT THU OCT 2 2014 Initial line of convection will be moving into KDEC shortly and KCMI toward 18Z or so, with TEMPO poeriods of IFR visibilities from heavy rain. Remainder of the TAF sites will be seeing a steady rain for a couple hours, then a break before the next round of convection currently in central Missouri moves northeast. The rain and storms will end with the passage of a cold front, which should be passing through KPIA/KSPI toward 06Z and the remainder of the TAF sites through 10Z. Cloud cover ahead and behind the front will be MVFR around 1500-2000 feet, although there may be a 1-3 hour window early Friday morning where the clouds scatter out for a time. && .ILX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH through late tonight FOR ILZ040-047-049>052. && $$ SHORT TERM...Geelhart LONG TERM...Auten AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1249 PM CDT THU OCT 2 2014 .DISCUSSION... 317 AM CDT RAINFALL AND THE POTENTIAL FOR SEVERE THUNDERSTORMS WILL BE THE MAIN FOCUS OF THIS COMPLEX FORECAST PERIOD...WITH UNSEASONABLY COLD AIR SPREADING IN BEHIND A STRONG COLD FRONT FOR THE WEEKEND. WATER VAPOR IMAGERY SHOWS A MASSIVE UPPER TROUGH OVER MOST OF CENTRAL AND WESTERN NORTH AMERICA WITH NUMEROUS WAVES EMBEDDED WITHIN THE FLOW TRIGGERING AREAS OF THUNDERSTORMS. SEVERAL OF THESE WAVES ARE LINED UP FROM TX/OK TO EASTERN WISCONSIN. AT THE SURFACE...LOOSELY ORGANIZED LOW PRESSURE IS OVER OKLAHOMA WITH A WARM FRONT EXTENDING EASTWARD FROM IT ACROSS CENTRAL MISSOURI AND SOUTH-CENTRAL ILLINOIS. WARM/MOIST ASCENT IS DRIVING CLUSTERS OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF NORTHERN MISSOURI AND CENTRAL ILLINOIS IN CONJUNCTION WITH AT LEAST ONE OF THE ABOVE MENTIONED UPPER WAVES. TODAY AND TONIGHT...THE UPPER WAVE AIDING THE SHOWER/THUNDER DEVELOPMENT OVER THE LOCAL AREA WILL LIFT OFF TO THE NORTHEAST THIS MORNING WITH CURRENT BANDS OF SHOWERS AND EMBEDDED THUNDER WILL EXIT TO THE NORTHEAST BY MID MORNING OR SO. SOME SPOTTY SHOWERS/THUNDER MAY LINGER THROUGH EARLY AFTERNOON BUT THERE IS NOT MUCH SUPPORT FOR LARGE SCALE PRECIP DEVELOPMENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON...WITH CURRENT CONVECTION ALSO HELPING TO LIMIT THE INCOMING MOISTURE FLUX. THE SURFACE LOW WILL BEGIN TO LIFT NORTHEAST AND BECOME MARGINALLY BETTER ORGANIZED THROUGH THE AFTERNOON AS THE MAIN UPPER TROUGH AXIS CURRENTLY PUSHING TOWARD WESTERN KS/OK/TX ADVANCES EASTWARD. IT DOES APPEAR THAT ONE OR SEVERAL MID/UPPER WAVES WILL LIFT NORTHEASTWARD AHEAD OF THE MAIN TROUGH WITH AT LEAST ONE CURRENTLY PRODUCING NEW CONVECTION ACROSS OKLAHOMA. THIS MAY RESULT IN AN INCREASE IN CONVECTION LOCALLY FROM MID TO LATE AFTERNOON...ESPECIALLY ACROSS THE WESTERN CWA. ANOTHER POTENTIAL SOURCE FOR CONVECTION WILL BE THE NORTHWARD ADVANCING WARM FRONTAL BOUNDARY WHICH IS EXPECTED TO PASS THIS AFTERNOON AND BE NORTH OF THE AREA BY THIS EVENING. CONFIDENCE IN TIMING/COVERAGE DETAILS FROM ABOUT MID MORNING THROUGH MID AFTERNOON IS LIMITED BUT WILL CONTINUE WITH THE IDEA THAT THERE WILL BE A MINIMUM OF ACTIVITY DURING THIS TIME...THOUGH THERE MAY BE SOME ACTIVITY AROUND. THE SURFACE LOW REMAINS ELONGATED AND TRACKS NORTHWARD ALONG AN INVERTED TROUGH AXIS FROM NORTHERN MISSOURI TO CENTRAL WISCONSIN BY EVENING. THE MAIN UPPER TROUGH AXIS WILL CONTINUE EAST AS WELL HELPING TO FOCUS NEW CONVECTIVE DEVELOPMENT ALONG THE COLD FRONT TRAILING THE LOW. THIS WILL LEAD TO STEADILY INCREASING COVERAGE OF SHOWERS/STORMS ACROSS THE WESTERN CWA LATE IN THE AFTERNOON WITH THE BULK OF THE ACTIVITY CROSSING THE AREA THIS EVENING AND TONIGHT AS THE LOW DEEPENS OVER NORTHERN LAKE MICHIGAN AND THE UPPER TROUGH AXIS APPROACHES. AN ORGANIZED LINE OF STORMS IS EXPECTED TO DEVELOP BUT THE MAIN QUESTION IS HOW FAR NORTH IN THE AREA IT MAY EXTEND. HEAVY RAINFALL IS A CONCERN WITH PRECIPITABLE WATER VALUES OF 1.6-1.7 INCHES. MUCH OF THE AREA SHOULD SEE AROUND AN INCH OF RAIN WITH HIGHER VALUES NEAR 2 INCHES POSSIBLE IF A LINE OF PARTICULARLY WELL ORGANIZED CONVECTION DOES CROSS THE AREA AHEAD OF A MORE WIDESPREAD AREA OF LESS INTENSE SHOWERS AND STORMS. SEVERE POTENTIAL WILL BE A CHALLENGE WITH IT CONDITIONAL ON THE EXTENT OF THE ACTIVITY ACROSS THE AREA TODAY. BETTER INSTABILITY WOULD LIKELY NEED TO BE ADVECTED IN WITH THE PASSAGE OF THE WARM FRONT. DEEP LAYER SHEAR WILL BE STRONG AS WILL THE OVERALL LARGE SCALE FORCING SO EVEN WEAK INSTABILITY COULD PRODUCE SEVERE WEATHER...WITH GUIDANCE SHOWING AROUND 1000 J/KG OF CAPE DEVELOPING BY LATE DAY WHICH WOULD BE PLENTY TO INCREASE THE SEVERE THREAT. DAMAGING STRAIGHT LINE WINDS WILL BE THE PRIMARY THREAT BUT A WELL DEVELOPED SQUALL LINE COULD SPAWN A FEW SHORT LIVED TORNADOES PROVIDED STRONG LOW LEVEL INSTABILITY DEVELOPS AND THERE IS SUFFICIENT LOW LEVEL TURNING. UNFORTUNATELY THERE ARE STILL TOO MANY UNCERTAIN VARIABLES TO HAVE GOOD CONFIDENCE IN THE THREAT FOR SEVERE WEATHER. FRIDAY AND SATURDAY...THE SURFACE LOW WILL BE MOVING INTO CENTRAL ONTARIO FRIDAY MORNING WITH THE COLD FRONT EXITING THE EASTERN CWA. THE EXIT OF RAIN TO THE EAST MAY LAG THE FRONT THANKS TO THE UPPER TROUGH AXIS STILL CROSSING THE AREA. ANOTHER PUSH OF ENERGY WILL BE RACING SOUTHEAST ACROSS THE PLAINS FRIDAY NIGHT SPAWNING AMPLIFICATION OF ANOTHER UPPER TROUGH AXIS WHICH WILL CROSS THE AREA FRIDAY AFTERNOON. THIS WILL LIKELY BRING ANOTHER ROUND OF SHOWERS WITH IT. YET ANOTHER WAVES RACES DOWN THE BACK SIDE OF THE NOW VERY AMPLIFIED LONGWAVE TROUGH HELPING IT TO CLOSE OFF OVER WISCONSIN FRIDAY NIGHT WHICH THEN LEADS TO ANOTHER EMBEDDED TROUGH AXIS PIVOTING ACROSS THE AREA SATURDAY...LEADING TO ADDITIONAL LOW CHANCES FOR SHOWERS DURING THE MORNING/MIDDAY. THE BIGGER STORY HOWEVER WILL BE THE PUSH OF COLD AIR BROUGHT IN BEHIND THE COLD FRONT FRIDAY. H85 TEMPS WILL CRASH TO ABOUT -2C BY FRIDAY EVENING. HIGHS FRIDAY WILL LIKELY OCCUR EARLY WITH TEMPS FALLING INTO THE UPPER 40S/LOWER 50S BY EVENING WITH GUSTY WEST-NORTHWEST WINDS. LOWS WILL FALL INTO THE UPPER 30S WITH FROST DEVELOPMENT UNLIKELY THANKS TO WINDS AND CLOUDS AS WELL AS SOME SHOWERS. HIGHS SATURDAY WILL ONLY REACH THE LOWER 50S AND SOME AREAS OF THE NORTHWEST MAY BE HELD INTO THE UPPER 40S. LOWS SATURDAY NIGHT WILL SHOULD FALL INTO THE MID TO UPPER 30S AS A WEAK RIDGE AXIS ARRIVES BY SUNDAY MORNING. WINDS MAY STAY STRONG ENOUGH AND CLOUD COVER EXTENSIVE ENOUGH TO PRECLUDE WIDESPREAD FROST DEVELOPMENT. MID LEVEL TEMPS WARM LATER SUNDAY BUT CLOUDS AND PRECIP MAY TEMPER WARMING SO AM EXPECTING HIGHS IN THE MID TO UPPER 50S WITH 60 POSSIBLE FAR SOUTH. SUNDAY THROUGH WEDNESDAY...THE EXPANSIVE UPPER TROUGH AND ASSOCIATED CYCLONIC FLOW WILL REMAIN IN PLACE THROUGH TUESDAY BEFORE IT STARTS TO TRANSITION NORTHEAST AND MUCH LOWER AMPLITUDE FLOW BUILDS IN. THIS WILL SET THE STAGE FOR THE PASSAGE OF EMBEDDED SHORTWAVES AND THEREFORE PERIODIC SHOWER CHANCES WITH MONDAY LOOKING TO BE A PERIOD OF HIGHER CHANCES FOR PRECIP. MID LEVELS WILL GRADUALLY WARM THOUGH SOME COOLING AND WARMING WILL BE MODULATED BY THE PASSAGE OF THE WAVES BUT OVERALL SURFACE TEMPS WILL BE ON A SLOW UPWARD TREND INTO MID WEEK...WITH UPPER 60S/LOWER 70S POSSIBLE AGAIN BY WEDNESDAY. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * SHOWERS/THUNDERSTORMS EXPECTED AFTER 23 UTC THROUGH AROUND 04 TO 05 UTC THIS EVENING. SHOWERS AND RAIN LIKELY PERSISTING OVERNIGHT. * IFR TO POSSIBLY LIFR CIGS LIKELY OVERNIGHT INTO FRIDAY MORNING. * WIND SHIFT TO THE WEST NORTHWEST FOLLOWING FROPA EARLY FRIDAY MORNING...WITH INCREASING SPEEDS DURING THE DAY. KJB //DISCUSSION...UPDATED 18Z... THE MAIN WEATHER CONCERNS CONTINUE TO REVOLVE AROUND THE CONVECTIVE ACTIVITY EXPECTED THE IMPACT THE TERMINALS BY EARLY THIS EVENING. PLENTY OF LOWER LEVEL MOISTURE HAS BEEN TRANSPORTED ACROSS THE AREA OUT AHEAD OF LOW PRESSURE CURRENTLY LOCATED ACROSS EASTERN KANSAS AND MISSOURI. THIS CONTINUES TO SUPPORT THE MVFR CIGS AROUND 2,000 FT AGL. NUMEROUS SHOWERS AND THUNDERSTORMS ALSO CONTINUE TO BUILD EAST NORTHEASTWARD ACROSS MISSOURI AND INTO WEST CENTRAL ILLINOIS. THIS ACTIVITY WILL APPROACH THE TERMINALS LATER THIS AFTERNOON AFTER 21-22 UTC. IT STILL APPEARS THE BEST CHANCES FOR THUNDERSTORMS WILL BE THROUGH MID TO LATE THIS EVENING...WITH PERIODS OF MODERATE TO HEAVY RAINFALL POSSIBLE AT TIMES. PERIODS OF MODERATE RAIN AND IFR TO LIFR CIGS ARE EXPECTED OVERNIGHT FOLLOWING THE THUNDERSTORM THREAT THIS EVENING. A SURFACE COLD FRONT SHOULD SHIFT OVER THE TERMINALS AROUND DAYBREAK FRIDAY...WITH A WIND SHIFT OUT OF THE WEST-NORTHWEST. CIGS SHOULD IMPROVE DURING THE MORNING...BUT GUSTY WEST-NORTHWEST WINDS OF 20 TO 25 KT ARE EXPECTED FOR MUCH OF THE DAY FRIDAY. KJB //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM-HIGH WITH WIND SPEED/DURATION. * MEDIUM-HIGH WITH SHOWERS/THUNDERSTORMS...MEDIUM ON TIMING. * MEDIUM-HIGH WITH IFR CIGS TONIGHT...LOW-MEDIUM WITH LIFR. KJB //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...CHANCE OF SHRA. SATURDAY...CHANCE OF SHRA. SUNDAY...SLIGHT CHANCE OF SHRA. MONDAY...CHANCE OF SHRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 1249 PM CDT MAIN MARINE FORECAST CONCERN IS WITH THE POTENTIAL FOR A PERIOD OF WESTERLY GALES FRIDAY AFTERNOON INTO SATURDAY MORNING...MAINLY ACROSS THE CENTRAL AND SOUTHERN PORTIONS OF THE LAKE. LOW PRESSURE OVER THE MID-MISSOURI VALLEY EARLY THIS AFTERNOON IS EXPECTED TO DEEPEN AS IT LIFTS NORTHEAST INTO SOUTHWESTERN WISCONSIN BY EARLY THIS EVENING...AND TO EASTERN LAKE SUPERIOR BY FRIDAY MORNING. IN THE PROCESS...A SHARP COLD FRONT WILL TRAIL ACROSS LAKE MICHIGAN OVERNIGHT...WITH WINDS SHIFTING TO THE WEST BEHIND THE FRONT. A COMBINATION OF MUCH COOLER AIR AND THE TIGHTENING OF THE SURFACE PRESSURE GRADIENT BETWEEN THE DEEPENING LOW AND HIGH PRESSURE BUILDING SOUTH ACROSS THE NORTHERN HIGH PLAINS WILL RESULT IN GUSTY WESTERLY WINDS...WITH FORECAST SOUNDINGS SUPPORTING A PERIOD OF 35 KT GALES DEVELOPING BY EARLY FRIDAY AFTERNOON AND CONTINUING INTO EARLY SATURDAY. A SECONDARY SURFACE TROUGH WILL MAINTAIN THE COOL ADVECTION ACROSS THE LAKE THROUGH THE DAY SATURDAY WITH WINDS SLOWLY EASING TO 25-30 KT SATURDAY NIGHT. DEEP LOW PRESSURE IS FORECAST TO REMAIN NORTH OF THE LAKES ACROSS FAR NORTHWEST ONTARIO AND JAMES BAY THROUGH SUNDAY...WITH SOME WEAKENING OF THE SURFACE PRESSURE GRADIENT OVER THE OHIO VALLEY AND SOUTHERN LAKES AS ANOTHER WEAKER LOW MOVES THROUGH THE REGION. THIS LOOKS TO KEEP WEST-SOUTHWEST WINDS AT/ABOVE 20 KT INTO SUNDAY. GUSTY WEST WINDS WILL LIKELY SUPPORT SMALL CRAFT ADVISORY CONDITIONS OVER THE ILLINOIS NEAR SHORE ZONES...WITH GALE FORCE GUSTS LATE FRIDAY AND FRIDAY NIGHT FARTHER EAST ALONG THE INDIANA SHORE. RATZER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WATCH...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744- LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876- LMZ878...4 PM FRIDAY TO 9 AM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1235 PM CDT Thu Oct 2 2014 .MESOSCALE DISCUSSION... ISSUED AT 1235 PM CDT THU OCT 2 2014 Enough clear patches have occurred over the southeast CWA to allow CAPE`s to rise into the 1500-2000 J/kg range, with higher values further south, per SPC mesoanalysis and GOES soundings. Line of convection currently extending from Decatur southeast will begin affecting east central Illinois early this afternoon, while regional radar mosaics showing storms quickly developing over south central Illinois near Salem and Flora. SPC watching this area closely for a potential watch. Larger area of strong to severe storms currently in central/south central Missouri progged by the High-Res ARW/NMM and HRRR models to be moving through central Illinois in the 4 pm time frame. && .UPDATE... ISSUED AT 1118 AM CDT THU OCT 2 2014 Have decided to issue a Flash Flood Watch for portions of the southwest CWA which were hit harder with the rains last night. This would include areas from Rushville southeast to Jacksonville, then eastward to Taylorville. Observed totals were heaviest in Christian County with 2-4 inches common, with similar totals along the Illinois River. Moderate risk of flash flooding is indicated in this area, with another 2 to 3 inches possible. Watch will be out shortly. UPDATE ISSUED AT 1029 AM CDT THU OCT 2 2014 Short break in the rain occurring over a large part of the forecast area this morning, however a large area of showers and thunderstorms was beginning to spread into the far western CWA. Latest HRRR guidance has this overspreading many areas west of I-55 into early afternoon, but the model has not been handling the narrow axis along the I-70 corridor very well. Storms expected to increase across the eastern CWA during the afternoon. Main cold front is still well off to the west, and should start to move into the western CWA during the evening hours. The rain trends should rapidly decrease behind the front after its passage overnight. Main question for this afternoon/evening will be with severe weather potential. Right now only areas east of I-55 are seeing scattered breaks in the clouds. MUCAPE values around 500 J/kg or so across the south half of the forecast area, per SPC mesoanalysis. RAP soundings from Springfield do bring CAPE`s up to around 1500 J/kg during the late afternoon as the precipitation becomes more concentrated west of the I-55 corridor. Rather moist soundings do favor heavy rain, with precipitable water around 1.8 inches which is near the 99th percentile for early October. Any severe weather that occurs will be more of a wind threat in our area due to the moist profile. && .SHORT TERM...(Today) ISSUED AT 258 AM CDT THU OCT 2 2014 06z/1am surface analysis shows warm front extending from central Missouri eastward into the Ohio River Valley. Several clusters of convection have been tracking along/north of the front overnight, aided by a 30-35kt 850mb jet streak oriented from the Southern Plains northeastward across the boundary. This activity will continue for the next few hours, but should begin to wane by mid-morning as front lifts further northward. Based on current radar trends and 00z model data, will carry likely PoPs along/northwest of I-70 through midday, with only chance PoPs further south. Meanwhile, low pressure developing over Oklahoma will track northeastward into southern Wisconsin by this evening. Line of thunderstorms is expected to develop along/ahead of associated cold front, with most model solutions keeping this convection just west of the KILX CWA until late afternoon/early evening. Have increased PoPs to categorical across the Illinois River Valley this afternoon in case storms get going faster than anticipated, but think bulk of activity will hold off until evening. Aside from the rain chances today, it will be another very warm day with highs ranging from the middle 70s far northwest around Galesburg to the middle 80s along/south of I-70. && .LONG TERM...(Tonight through Wednesday) ISSUED AT 258 AM CDT THU OCT 2 2014 Latest Day 1 convective outlook from SPC places all of central/southeast Illinois under a slight risk for severe weather tonight. With a very warm/humid air mass surging northward ahead of an approaching cold front, resulting CAPE values will likely exceed 1500J/kg later today. In addition, low-level wind shear will be increasing with 0-6km bulk shear values generally in the 30-40kt range. These favorable parameters combined with strong convergence along the cold front will lead to the development of a line of thunderstorms this evening. Models generally develop the storms along the Mississippi River by late afternoon, then push them eastward to the I-55 corridor by mid-evening and into east-central Illinois shortly after midnight. Main severe weather threat will be strong/damaging winds, although highest probabilities for widespread severe will likely remain further southwest from the St. Louis area southwestward to Texas. With precipitable water values climbing over 1.75, high rainfall rates will be likely with any storms that develop. Localized flash flooding may develop within the strongest storms: however, recent rainfall amounts have not been great enough over a wide enough area to warrant a Flash Flood Watch at this time. Front will push into Indiana by Friday morning, bringing an end to the greatest rain chances. Still some model discrepancy concerning timing of frontal departure, with the ECMWF being the slowest. Have therefore hung on to chance PoPs early Friday morning along/east of I-57. A secondary upper wave currently evident on water vapor imagery over Alberta will dive southeastward Friday afternoon/evening, amplifying the mean trough over the Great Lakes/Midwest. Synoptic lift and steep mid-level lapse rates associated with this feature will be enough to warrant a slight chance for showers, mainly during the afternoon. Main weather story on Friday will be the windy and sharply cooler conditions. Tightening pressure gradient between departing front and approaching Canadian high pressure will lead to strong W/NW winds gusting to between 30 and 35mph. Temperatures will struggle to rise much at all from morning lows, with readings remaining in the 60s. With 850mb temps progged to drop into the -3 to -5C range, low temperatures by Saturday morning will fall into the middle 30s...representing a nearly 50 degree temp drop from expected high temps today! Due to a continued brisk northwesterly breeze, am not expecting any frost to develop Friday night. Heart of cold air mass will be in place across Illinois on Saturday, with highs struggling to reach the middle to upper 50s and overnight lows once again dropping into the middle to upper 30s. With much lighter winds expected, a few patches of frost will be possible by Sunday morning, especially if skies can remain clear ahead of the next approaching short-wave trough. After that, the Midwest will be dominated by northwesterly upper-level flow through Tuesday before trough retreats into Canada by the middle and end of next week. This will mean continued below normal temps in the 60s through Tuesday, followed by a warming trend and a return to the 70s by Wednesday and Thursday. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 1226 PM CDT THU OCT 2 2014 Initial line of convection will be moving into KDEC shortly and KCMI toward 18Z or so, with TEMPO poeriods of IFR visibilities from heavy rain. Remainder of the TAF sites will be seeing a steady rain for a couple hours, then a break before the next round of convection currently in central Missouri moves northeast. The rain and storms will end with the passage of a cold front, which should be passing through KPIA/KSPI toward 06Z and the remainder of the TAF sites through 10Z. Cloud cover ahead and behind the front will be MVFR around 1500-2000 feet, although there may be a 1-3 hour window early Friday morning where the clouds scatter out for a time. && .ILX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH through late tonight FOR ILZ040-047-049>052. && $$ MESOSCALE...Geelhart UPDATE...Geelhart SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Geelhart
AREA FORECAST DISCUSSION
NWS CHICAGO/ROMEOVILLE IL
1231 PM CDT THU OCT 2 2014 .DISCUSSION... 317 AM CDT RAINFALL AND THE POTENTIAL FOR SEVERE THUNDERSTORMS WILL BE THE MAIN FOCUS OF THIS COMPLEX FORECAST PERIOD...WITH UNSEASONABLY COLD AIR SPREADING IN BEHIND A STRONG COLD FRONT FOR THE WEEKEND. WATER VAPOR IMAGERY SHOWS A MASSIVE UPPER TROUGH OVER MOST OF CENTRAL AND WESTERN NORTH AMERICA WITH NUMEROUS WAVES EMBEDDED WITHIN THE FLOW TRIGGERING AREAS OF THUNDERSTORMS. SEVERAL OF THESE WAVES ARE LINED UP FROM TX/OK TO EASTERN WISCONSIN. AT THE SURFACE...LOOSELY ORGANIZED LOW PRESSURE IS OVER OKLAHOMA WITH A WARM FRONT EXTENDING EASTWARD FROM IT ACROSS CENTRAL MISSOURI AND SOUTH-CENTRAL ILLINOIS. WARM/MOIST ASCENT IS DRIVING CLUSTERS OF SHOWERS AND THUNDERSTORMS ACROSS MUCH OF NORTHERN MISSOURI AND CENTRAL ILLINOIS IN CONJUNCTION WITH AT LEAST ONE OF THE ABOVE MENTIONED UPPER WAVES. TODAY AND TONIGHT...THE UPPER WAVE AIDING THE SHOWER/THUNDER DEVELOPMENT OVER THE LOCAL AREA WILL LIFT OFF TO THE NORTHEAST THIS MORNING WITH CURRENT BANDS OF SHOWERS AND EMBEDDED THUNDER WILL EXIT TO THE NORTHEAST BY MID MORNING OR SO. SOME SPOTTY SHOWERS/THUNDER MAY LINGER THROUGH EARLY AFTERNOON BUT THERE IS NOT MUCH SUPPORT FOR LARGE SCALE PRECIP DEVELOPMENT THROUGH MIDDAY OR EVEN EARLY AFTERNOON...WITH CURRENT CONVECTION ALSO HELPING TO LIMIT THE INCOMING MOISTURE FLUX. THE SURFACE LOW WILL BEGIN TO LIFT NORTHEAST AND BECOME MARGINALLY BETTER ORGANIZED THROUGH THE AFTERNOON AS THE MAIN UPPER TROUGH AXIS CURRENTLY PUSHING TOWARD WESTERN KS/OK/TX ADVANCES EASTWARD. IT DOES APPEAR THAT ONE OR SEVERAL MID/UPPER WAVES WILL LIFT NORTHEASTWARD AHEAD OF THE MAIN TROUGH WITH AT LEAST ONE CURRENTLY PRODUCING NEW CONVECTION ACROSS OKLAHOMA. THIS MAY RESULT IN AN INCREASE IN CONVECTION LOCALLY FROM MID TO LATE AFTERNOON...ESPECIALLY ACROSS THE WESTERN CWA. ANOTHER POTENTIAL SOURCE FOR CONVECTION WILL BE THE NORTHWARD ADVANCING WARM FRONTAL BOUNDARY WHICH IS EXPECTED TO PASS THIS AFTERNOON AND BE NORTH OF THE AREA BY THIS EVENING. CONFIDENCE IN TIMING/COVERAGE DETAILS FROM ABOUT MID MORNING THROUGH MID AFTERNOON IS LIMITED BUT WILL CONTINUE WITH THE IDEA THAT THERE WILL BE A MINIMUM OF ACTIVITY DURING THIS TIME...THOUGH THERE MAY BE SOME ACTIVITY AROUND. THE SURFACE LOW REMAINS ELONGATED AND TRACKS NORTHWARD ALONG AN INVERTED TROUGH AXIS FROM NORTHERN MISSOURI TO CENTRAL WISCONSIN BY EVENING. THE MAIN UPPER TROUGH AXIS WILL CONTINUE EAST AS WELL HELPING TO FOCUS NEW CONVECTIVE DEVELOPMENT ALONG THE COLD FRONT TRAILING THE LOW. THIS WILL LEAD TO STEADILY INCREASING COVERAGE OF SHOWERS/STORMS ACROSS THE WESTERN CWA LATE IN THE AFTERNOON WITH THE BULK OF THE ACTIVITY CROSSING THE AREA THIS EVENING AND TONIGHT AS THE LOW DEEPENS OVER NORTHERN LAKE MICHIGAN AND THE UPPER TROUGH AXIS APPROACHES. AN ORGANIZED LINE OF STORMS IS EXPECTED TO DEVELOP BUT THE MAIN QUESTION IS HOW FAR NORTH IN THE AREA IT MAY EXTEND. HEAVY RAINFALL IS A CONCERN WITH PRECIPITABLE WATER VALUES OF 1.6-1.7 INCHES. MUCH OF THE AREA SHOULD SEE AROUND AN INCH OF RAIN WITH HIGHER VALUES NEAR 2 INCHES POSSIBLE IF A LINE OF PARTICULARLY WELL ORGANIZED CONVECTION DOES CROSS THE AREA AHEAD OF A MORE WIDESPREAD AREA OF LESS INTENSE SHOWERS AND STORMS. SEVERE POTENTIAL WILL BE A CHALLENGE WITH IT CONDITIONAL ON THE EXTENT OF THE ACTIVITY ACROSS THE AREA TODAY. BETTER INSTABILITY WOULD LIKELY NEED TO BE ADVECTED IN WITH THE PASSAGE OF THE WARM FRONT. DEEP LAYER SHEAR WILL BE STRONG AS WILL THE OVERALL LARGE SCALE FORCING SO EVEN WEAK INSTABILITY COULD PRODUCE SEVERE WEATHER...WITH GUIDANCE SHOWING AROUND 1000 J/KG OF CAPE DEVELOPING BY LATE DAY WHICH WOULD BE PLENTY TO INCREASE THE SEVERE THREAT. DAMAGING STRAIGHT LINE WINDS WILL BE THE PRIMARY THREAT BUT A WELL DEVELOPED SQUALL LINE COULD SPAWN A FEW SHORT LIVED TORNADOES PROVIDED STRONG LOW LEVEL INSTABILITY DEVELOPS AND THERE IS SUFFICIENT LOW LEVEL TURNING. UNFORTUNATELY THERE ARE STILL TOO MANY UNCERTAIN VARIABLES TO HAVE GOOD CONFIDENCE IN THE THREAT FOR SEVERE WEATHER. FRIDAY AND SATURDAY...THE SURFACE LOW WILL BE MOVING INTO CENTRAL ONTARIO FRIDAY MORNING WITH THE COLD FRONT EXITING THE EASTERN CWA. THE EXIT OF RAIN TO THE EAST MAY LAG THE FRONT THANKS TO THE UPPER TROUGH AXIS STILL CROSSING THE AREA. ANOTHER PUSH OF ENERGY WILL BE RACING SOUTHEAST ACROSS THE PLAINS FRIDAY NIGHT SPAWNING AMPLIFICATION OF ANOTHER UPPER TROUGH AXIS WHICH WILL CROSS THE AREA FRIDAY AFTERNOON. THIS WILL LIKELY BRING ANOTHER ROUND OF SHOWERS WITH IT. YET ANOTHER WAVES RACES DOWN THE BACK SIDE OF THE NOW VERY AMPLIFIED LONGWAVE TROUGH HELPING IT TO CLOSE OFF OVER WISCONSIN FRIDAY NIGHT WHICH THEN LEADS TO ANOTHER EMBEDDED TROUGH AXIS PIVOTING ACROSS THE AREA SATURDAY...LEADING TO ADDITIONAL LOW CHANCES FOR SHOWERS DURING THE MORNING/MIDDAY. THE BIGGER STORY HOWEVER WILL BE THE PUSH OF COLD AIR BROUGHT IN BEHIND THE COLD FRONT FRIDAY. H85 TEMPS WILL CRASH TO ABOUT -2C BY FRIDAY EVENING. HIGHS FRIDAY WILL LIKELY OCCUR EARLY WITH TEMPS FALLING INTO THE UPPER 40S/LOWER 50S BY EVENING WITH GUSTY WEST-NORTHWEST WINDS. LOWS WILL FALL INTO THE UPPER 30S WITH FROST DEVELOPMENT UNLIKELY THANKS TO WINDS AND CLOUDS AS WELL AS SOME SHOWERS. HIGHS SATURDAY WILL ONLY REACH THE LOWER 50S AND SOME AREAS OF THE NORTHWEST MAY BE HELD INTO THE UPPER 40S. LOWS SATURDAY NIGHT WILL SHOULD FALL INTO THE MID TO UPPER 30S AS A WEAK RIDGE AXIS ARRIVES BY SUNDAY MORNING. WINDS MAY STAY STRONG ENOUGH AND CLOUD COVER EXTENSIVE ENOUGH TO PRECLUDE WIDESPREAD FROST DEVELOPMENT. MID LEVEL TEMPS WARM LATER SUNDAY BUT CLOUDS AND PRECIP MAY TEMPER WARMING SO AM EXPECTING HIGHS IN THE MID TO UPPER 50S WITH 60 POSSIBLE FAR SOUTH. SUNDAY THROUGH WEDNESDAY...THE EXPANSIVE UPPER TROUGH AND ASSOCIATED CYCLONIC FLOW WILL REMAIN IN PLACE THROUGH TUESDAY BEFORE IT STARTS TO TRANSITION NORTHEAST AND MUCH LOWER AMPLITUDE FLOW BUILDS IN. THIS WILL SET THE STAGE FOR THE PASSAGE OF EMBEDDED SHORTWAVES AND THEREFORE PERIODIC SHOWER CHANCES WITH MONDAY LOOKING TO BE A PERIOD OF HIGHER CHANCES FOR PRECIP. MID LEVELS WILL GRADUALLY WARM THOUGH SOME COOLING AND WARMING WILL BE MODULATED BY THE PASSAGE OF THE WAVES BUT OVERALL SURFACE TEMPS WILL BE ON A SLOW UPWARD TREND INTO MID WEEK...WITH UPPER 60S/LOWER 70S POSSIBLE AGAIN BY WEDNESDAY. MDB && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 18Z... * SHOWERS/THUNDERSTORMS EXPECTED AFTER 23 UTC THROUGH AROUND 04 TO 05 UTC THIS EVENING. SHOWERS AND RAIN LIKELY PERSISTING OVERNIGHT. * IFR TO POSSIBLY LIFR CIGS LIKELY OVERNIGHT INTO FRIDAY MORNING. * WIND SHIFT TO THE WEST NORTHWEST FOLLOWING FROPA EARLY FRIDAY MORNING...WITH INCREASING SPEEDS DURING THE DAY. KJB //DISCUSSION...UPDATED 18Z... THE MAIN WEATHER CONCERNS CONTINUE TO REVOLVE AROUND THE CONVECTIVE ACTIVITY EXPECTED THE IMPACT THE TERMINALS BY EARLY THIS EVENING. PLENTY OF LOWER LEVEL MOISTURE HAS BEEN TRANSPORTED ACROSS THE AREA OUT AHEAD OF LOW PRESSURE CURRENTLY LOCATED ACROSS EASTERN KANSAS AND MISSOURI. THIS CONTINUES TO SUPPORT THE MVFR CIGS AROUND 2,000 FT AGL. NUMEROUS SHOWERS AND THUNDERSTORMS ALSO CONTINUE TO BUILD EAST NORTHEASTWARD ACROSS MISSOURI AND INTO WEST CENTRAL ILLINOIS. THIS ACTIVITY WILL APPROACH THE TERMINALS LATER THIS AFTERNOON AFTER 21-22 UTC. IT STILL APPEARS THE BEST CHANCES FOR THUNDERSTORMS WILL BE THROUGH MID TO LATE THIS EVENING...WITH PERIODS OF MODERATE TO HEAVY RAINFALL POSSIBLE AT TIMES. PERIODS OF MODERATE RAIN AND IFR TO LIFR CIGS ARE EXPECTED OVERNIGHT FOLLOWING THE THUNDERSTORM THREAT THIS EVENING. A SURFACE COLD FRONT SHOULD SHIFT OVER THE TERMINALS AROUND DAYBREAK FRIDAY...WITH A WIND SHIFT OUT OF THE WEST-NORTHWEST. CIGS SHOULD IMPROVE DURING THE MORNING...BUT GUSTY WEST-NORTHWEST WINDS OF 20 TO 25 KT ARE EXPECTED FOR MUCH OF THE DAY FRIDAY. KJB //ORD AND MDW CONFIDENCE...UPDATED 18Z... * MEDIUM-HIGH WITH WIND SPEED/DURATION. * MEDIUM-HIGH WITH SHOWERS/THUNDERSTORMS...MEDIUM ON TIMING. * MEDIUM-HIGH WITH IFR CIGS TONIGHT...LOW-MEDIUM WITH LIFR. KJB //OUTLOOK FOR ORD/MDW FOR 00Z SATURDAY-12Z THURSDAY...UPDATED 12Z... FRIDAY NIGHT...CHANCE OF SHRA. SATURDAY...CHANCE OF SHRA. SUNDAY...SLIGHT CHANCE OF SHRA. MONDAY...CHANCE OF SHRA. TUESDAY...VFR. WEDNESDAY...VFR. RODRIGUEZ && .MARINE... 441 AM CDT SURFACE RIDGE OF HIGH PRESSURE SPANS THE ATLANTIC COAST AND LOW PRESSURE IS OVER THE SOUTHERN PLAINS THIS MORNING...WITH SOUTH TO SOUTHEAST WINDS CURRENTLY BEING OBSERVED ACROSS THE LAKE. THE SURFACE PATTERN HAS TIGHTENED THIS MORNING AND HAS RESULTED IN SOME SLIGHT INCREASE IN SPEEDS...MAINLY ACROSS THE SOUTH HALF OF THE LAKE WHERE 15 TO 25 KT WINDS ARE BEING OBSERVED. THESE CURRENT SPEEDS WILL LIKELY DIMINISH THIS MORNING...WITH SOUTH WINDS OF 10 TO 20 KT BEING OBSERVED FOR THE REST OF THE DAY. THE LOW PRESSURE OVER THE SOUTHERN PLAINS WILL LIFT NORTHEAST TO THE UPPER MISSISSIPPI VALLEY TODAY...AND THEN CONTINUE NORTHEAST TO THE CENTRAL GREAT LAKES TONIGHT INTO EARLY FRIDAY MORNING WHILE ALSO STRENGTHENING. THIS WILL RESULT IN A VARYING WIND DIRECTION AS WELL AS AN INCREASE IN SPEEDS THROUGH FRIDAY. ALTHOUGH WINDS WILL BE INCREASING THROUGH THIS PERIOD...IT APPEARS THAT SPEEDS WILL REALLY RAMP UP LATE FRIDAY AFTERNOON INTO THE EARLY EVENING. WEST GALES DO APPEAR TO BE A DEFINITE POSSIBILITY FRIDAY NIGHT INTO EARLY SATURDAY MORNING OVER THE SOUTHERN HALF OF THE LAKE...AND SO ISSUED A GALE WATCH. THE NEARSHORE WATERS WILL BE ON THE FRINGE OF THE STRONGEST WINDS BUT WITH THE INDIANA NEARSHORE WATERS POSSIBLY OBSERVING THESE GALES AS WELL...DID GO AHEAD AND INCLUDE A PORTION OF THE INDIANA NEARSHORE ZONES. AS THE LOW CONTINUES NORTH THROUGH ONTARIO TO HUDSON BAY SATURDAY AND SATURDAY NIGHT...WEST WINDS TO 30 KT WILL LIKELY CONTINUE BEFORE DIMINISHING ON SUNDAY. RODRIGUEZ && .LOT WATCHES/WARNINGS/ADVISORIES... IL...NONE. IN...NONE. LM...GALE WATCH...LMZ080-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675-LMZ744- LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872-LMZ874-LMZ876- LMZ878...4 PM FRIDAY TO 9 AM SATURDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion NATIONAL WEATHER SERVICE LINCOLN IL 1121 AM CDT Thu Oct 2 2014 .UPDATE... ISSUED AT 1118 AM CDT THU OCT 2 2014 Have decided to issue a Flash Flood Watch for portions of the southwest CWA which were hit harder with the rains last night. This would include areas from Rushville southeast to Jacksonville, then eastward to Taylorville. Observed totals were heaviest in Christian County with 2-4 inches common, with similar totals along the Illinois River. Moderate risk of flash flooding is indicated in this area, with another 2 to 3 inches possible. Watch will be out shortly. UPDATE ISSUED AT 1029 AM CDT THU OCT 2 2014 Short break in the rain occurring over a large part of the forecast area this morning, however a large area of showers and thunderstorms was beginning to spread into the far western CWA. Latest HRRR guidance has this overspreading many areas west of I-55 into early afternoon, but the model has not been handling the narrow axis along the I-70 corridor very well. Storms expected to increase across the eastern CWA during the afternoon. Main cold front is still well off to the west, and should start to move into the western CWA during the evening hours. The rain trends should rapidly decrease behind the front after its passage overnight. Main question for this afternoon/evening will be with severe weather potential. Right now only areas east of I-55 are seeing scattered breaks in the clouds. MUCAPE values around 500 J/kg or so across the south half of the forecast area, per SPC mesoanalysis. RAP soundings from Springfield do bring CAPE`s up to around 1500 J/kg during the late afternoon as the precipitation becomes more concentrated west of the I-55 corridor. Rather moist soundings do favor heavy rain, with precipitable water around 1.8 inches which is near the 99th percentile for early October. Any severe weather that occurs will be more of a wind threat in our area due to the moist profile. && .SHORT TERM...(Today) ISSUED AT 258 AM CDT THU OCT 2 2014 06z/1am surface analysis shows warm front extending from central Missouri eastward into the Ohio River Valley. Several clusters of convection have been tracking along/north of the front overnight, aided by a 30-35kt 850mb jet streak oriented from the Southern Plains northeastward across the boundary. This activity will continue for the next few hours, but should begin to wane by mid-morning as front lifts further northward. Based on current radar trends and 00z model data, will carry likely PoPs along/northwest of I-70 through midday, with only chance PoPs further south. Meanwhile, low pressure developing over Oklahoma will track northeastward into southern Wisconsin by this evening. Line of thunderstorms is expected to develop along/ahead of associated cold front, with most model solutions keeping this convection just west of the KILX CWA until late afternoon/early evening. Have increased PoPs to categorical across the Illinois River Valley this afternoon in case storms get going faster than anticipated, but think bulk of activity will hold off until evening. Aside from the rain chances today, it will be another very warm day with highs ranging from the middle 70s far northwest around Galesburg to the middle 80s along/south of I-70. && .LONG TERM...(Tonight through Wednesday) ISSUED AT 258 AM CDT THU OCT 2 2014 Latest Day 1 convective outlook from SPC places all of central/southeast Illinois under a slight risk for severe weather tonight. With a very warm/humid air mass surging northward ahead of an approaching cold front, resulting CAPE values will likely exceed 1500J/kg later today. In addition, low-level wind shear will be increasing with 0-6km bulk shear values generally in the 30-40kt range. These favorable parameters combined with strong convergence along the cold front will lead to the development of a line of thunderstorms this evening. Models generally develop the storms along the Mississippi River by late afternoon, then push them eastward to the I-55 corridor by mid-evening and into east-central Illinois shortly after midnight. Main severe weather threat will be strong/damaging winds, although highest probabilities for widespread severe will likely remain further southwest from the St. Louis area southwestward to Texas. With precipitable water values climbing over 1.75, high rainfall rates will be likely with any storms that develop. Localized flash flooding may develop within the strongest storms: however, recent rainfall amounts have not been great enough over a wide enough area to warrant a Flash Flood Watch at this time. Front will push into Indiana by Friday morning, bringing an end to the greatest rain chances. Still some model discrepancy concerning timing of frontal departure, with the ECMWF being the slowest. Have therefore hung on to chance PoPs early Friday morning along/east of I-57. A secondary upper wave currently evident on water vapor imagery over Alberta will dive southeastward Friday afternoon/evening, amplifying the mean trough over the Great Lakes/Midwest. Synoptic lift and steep mid-level lapse rates associated with this feature will be enough to warrant a slight chance for showers, mainly during the afternoon. Main weather story on Friday will be the windy and sharply cooler conditions. Tightening pressure gradient between departing front and approaching Canadian high pressure will lead to strong W/NW winds gusting to between 30 and 35mph. Temperatures will struggle to rise much at all from morning lows, with readings remaining in the 60s. With 850mb temps progged to drop into the -3 to -5C range, low temperatures by Saturday morning will fall into the middle 30s...representing a nearly 50 degree temp drop from expected high temps today! Due to a continued brisk northwesterly breeze, am not expecting any frost to develop Friday night. Heart of cold air mass will be in place across Illinois on Saturday, with highs struggling to reach the middle to upper 50s and overnight lows once again dropping into the middle to upper 30s. With much lighter winds expected, a few patches of frost will be possible by Sunday morning, especially if skies can remain clear ahead of the next approaching short-wave trough. After that, the Midwest will be dominated by northwesterly upper-level flow through Tuesday before trough retreats into Canada by the middle and end of next week. This will mean continued below normal temps in the 60s through Tuesday, followed by a warming trend and a return to the 70s by Wednesday and Thursday. && .AVIATION...(For the 12Z TAFS through 12Z Friday morning) ISSUED AT 700 AM CDT THU OCT 2 2014 The timing of thunderstorms over the next 24 hours will be the main concern, and the associated IFR/LIFR conditions during storms. Based on current radar trends, there should be a break in the showers and storms at all terminals this morning. SPI will see the return of some storms the soonest as a band of storms moves out of NE Missouri and reaches SPI as soon as 16z. That convection could reach to DEC as well, and have indicated that in the TAFS. PIA, BMI and CMI could remain dry for a longer period, possibly well into the afternoon or early evening. CMI looks to be closer to the current storm track, so may see a few showers pass close by to the south during the day. The main threat for strong to severe storms looks to be this evening for PIA, SPI and BMI. A 3-hour tempo for heavy rain and storms with IFR conditions was included in the TAFs for the current best-estimate on timing of the line of storms. We estimated 00z for PIA and 04z for CMI, but those hours may need adjustment as the cold frontal timing becomes more apparent. After the cold front passes, winds will begin to shift to the SW then W, with some gusts possible by morning. Also, MVFR clouds are likely to persist through 12z/7am Friday. && .ILX WATCHES/WARNINGS/ADVISORIES... FLASH FLOOD WATCH through late tonight FOR ILZ040-047-049>052. && $$ UPDATE...Geelhart SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Shimon
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
602 PM CDT THU OCT 2 2014 ...UPDATE TO AVIATION... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 158 PM CDT THU OCT 2 2014 THE FIRST COLD FRONT IS EXITING OUR EASTERN TIER OF COUNTIES AS I WRITE THIS DISCUSSION. IN THE WEST, CLOUDS HAVE BEEN SCATTERING OUT AND WINDS SUBSIDING SLIGHTLY. BY 22Z, THE WESTERN HALF OF THE CWA SHOULD HAVE CLEARED OUT, AND BY 02Z THE EASTERN HALF. THE PRESSURE GRADIENT WILL SLACKEN NEAR SUNSET, AND WINDS SHOULD GO LIGHT AND VARIABLE EVERYWHERE BY THAT TIME. NORMALLY, WITH RECENT RAINS AND LIGHT WINDS, I AT FIRST CONSIDERED PUTTING IN SOME MENTION OF FOG LATE TONIGHT. BUT THEN I REALIZED ANOTHER COLD FRONT WILL SWEEP THROUGH PRIOR TO SUNRISE FRIDAY. WINDS BEHIND THE OVERNIGHT FRONTAL PASSAGE WILL SWITCH AROUND TO THE NORTH AT 18G28KT, THUS NEGATING THE CHANCE FOR FOG DEVELOPMENT. LOWS TONIGHT ARE VERY CLOSE TO WHAT THE NAMDNG25 AND RAP MODELS ARE FORECASTING, RANGING FROM NEAR 40F DEGREES IN WAKEENEY, SCOTT CITY AND SYRACUSE, TO THE MID 40S FROM LARNED TO DODGE CITY TO LIBERAL, AND TO THE UPPER 40S IN THE COLDWATER AND MEDICINE LODGE AREAS. THAT 2ND COLD FRONT PASSING THROUGH DURING THE EARLY MORNING HOURS WILL USHER IN COLD AIR. THE STRONG NORTH TO NORTHWEST WINDS WILL PERSIST INTO THE MID AFTERNOON. EVEN THOUGH JUST A FEW CLOUDS WILL BE PASSING AND SKIES WILL REMAIN MOSTLY SUNNY, TEMPERATURES WILL STILL STRUGGLE TO RISE IN THE COLD AIR MASS. HIGHS ON FRIDAY WILL ONLY REACH AROUND THE 60F DEGREE MARK FRIDAY NORTHWEST OF A JOHNSON CITY TO GARDEN CITY TO HAYS LINE. WINDS WILL DROP OFF TOWARD SUNSET AS THE PRESSURE GRADIENT FALLS, AND TEMPERATURES WILL DROP RAPIDLY DURING FRIDAY EVENING. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 248 PM CDT THU OCT 2 2014 MEDIUM RANGE MODELS INDICATE A DEEP UPPER LEVEL TROUGH OF LOW PRESSURE SHIFTING EASTWARD ACROSS THE UPPER MIDWEST AND THE GREAT LAKES REGION SATURDAY WHILE A NORTHWESTERLY FLOW ALOFT DEVELOPS ACROSS THE WESTERN HIGH PLAINS. ALTHOUGH A SERIES OF H5 VORT MAXIMA WILL CONTINUE TO CYCLE SOUTHEAST ACROSS THE NORTHERN PLAINS INTO THE TROUGH AXIS ACROSS THE UPPER MIDWEST THROUGH EARLY NEXT WEEK, A NUMBER OF WEAK FRONTAL PASSAGES ASSOCIATED WITH THE SHORTWAVES WILL HELP USHER SURGES OF DRIER AIR SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, PRECIP IS NOT EXPECTED ACROSS THE AREA THROUGH AT LEAST MONDAY. ARCTIC HIGH PRESSURE SLIDING SOUTHEASTWARD ACROSS THE NORTHERN PLAINS INTO THE HIGH PLAINS OF WESTERN KANSAS WILL HELP REINFORCE THE COOLER AIR MASS ALREADY IN PLACE ACROSS THE REGION FRIDAY NIGHT. THE GFS/ECMWF SHOW H85 TEMPERATURES AROUND 5C IN CENTRAL KANSAS WITH THE 0C ISOTHERM WELL OFF TO THE NORTHEAST IN EASTERN NEBRASKA AND NORTHEASTERN KANSAS. ADDITIONALLY, THE MODELS INDICATE A LEE SIDE TROUGH BEGINNING TO DEVELOP BY EARLY SATURDAY MORNING TURNING LIGHT SURFACE WINDS MORE WEST TO SOUTHWESTERLY ACROSS EXTREME SOUTHWEST KANSAS WHERE H85 TEMPERATURES ARE EXPECTED TO REMAIN CLOSER TO 10C. WITH THE HELP OF A DOWNSLOPE FLOW, LOW TEMPERATURES WILL REMAIN WELL ABOVE FREEZING IN EXTREME SOUTHWEST KANSAS AND ALONG THE OKLAHOMA BORDER WITH LOWS NEAR 40F. HOWEVER, LOWS ARE EXPECTED TO FALL INTO THE MID TO UPPER 30(F) IN CENTRAL KANSAS WITH AREAS OF PATCHY FROST POSSIBLE NEAR THE I-70 CORRIDOR. LEE SIDE TROUGHING WILL STRENGTHEN SOMEWHAT SATURDAY ENHANCING THE SOUTHWESTERLY FLOW ACROSS EXTREME SOUTHWEST KANSAS DRAWING WARMER AIR BACK INTO PORTIONS OF WESTERN KANSAS. HOWEVER, MUCH COOLER AIR IS EXPECTED TO REMAIN LOCKED IN ACROSS EASTERN AND PORTIONS OF CENTRAL KANSAS RESULTING IN A TIGHT TEMPERATURE GRADIENT EAST TO WEST ACROSS THE STATE. THE GFS/ECMWF SHOW H85 TEMPERATURES SLOWLY REACHING UP NEAR 10C ACROSS CENTRAL KANSAS TOWARD MID SATURDAY AFTERNOON WITH H85 TEMPERATURES A LITTLE ABOVE 15C IN EXTREME SOUTHWEST KANSAS. LOOK FOR HIGHS EASILY UP INTO THE 70S(F) ACROSS FAR SOUTHWEST KANSAS SATURDAY AFTERNOON WITH TEMPERATURES STRUGGLING TO REACH THE 70S(F), IF AT ALL, IN CENTRAL KANSAS NEAR THE I-70 CORRIDOR DEPENDING WHERE THE GRADIENT SETS UP. A GRADUAL WARMING TREND WILL THEN PROCEED INTO EARLY NEXT WEEK AS A NORTHWEST FLOW ALOFT SETS UP ACROSS THE WESTERN HIGH PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 600 PM CDT THU OCT 2 2014 FLIGHT CONDITIONS WILL BE VFR THROUGH TAF PD. WINDS WILL WEAKEN AFTER 01Z. ANOTHER FRONT ALONG WITH MIXING WILL BRING INCREASING NNW/NW/GUSTY WINDS BY TOMORROW MORNING IN THE 15-25 KT RANGE. && .PRELIMINARY POINT TEMPS/POPS... DDC 44 62 38 73 / 0 0 0 0 GCK 42 61 37 74 / 0 0 0 0 EHA 43 62 40 75 / 0 0 0 0 LBL 44 64 40 75 / 0 0 0 0 HYS 40 60 36 70 / 0 0 0 0 P28 47 65 38 72 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURKE LONG TERM...JJOHNSON AVIATION...SUGDEN
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
255 PM CDT THU OCT 2 2014 ...UPDATE TO LONG TERM... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 158 PM CDT THU OCT 2 2014 THE FIRST COLD FRONT IS EXITING OUR EASTERN TIER OF COUNTIES AS I WRITE THIS DISCUSSION. IN THE WEST, CLOUDS HAVE BEEN SCATTERING OUT AND WINDS SUBSIDING SLIGHTLY. BY 22Z, THE WESTERN HALF OF THE CWA SHOULD HAVE CLEARED OUT, AND BY 02Z THE EASTERN HALF. THE PRESSURE GRADIENT WILL SLACKEN NEAR SUNSET, AND WINDS SHOULD GO LIGHT AND VARIABLE EVERYWHERE BY THAT TIME. NORMALLY, WITH RECENT RAINS AND LIGHT WINDS, I AT FIRST CONSIDERED PUTTING IN SOME MENTION OF FOG LATE TONIGHT. BUT THEN I REALIZED ANOTHER COLD FRONT WILL SWEEP THROUGH PRIOR TO SUNRISE FRIDAY. WINDS BEHIND THE OVERNIGHT FRONTAL PASSAGE WILL SWITCH AROUND TO THE NORTH AT 18G28KT, THUS NEGATING THE CHANCE FOR FOG DEVELOPMENT. LOWS TONIGHT ARE VERY CLOSE TO WHAT THE NAMDNG25 AND RAP MODELS ARE FORECASTING, RANGING FROM NEAR 40F DEGREES IN WAKEENEY, SCOTT CITY AND SYRACUSE, TO THE MID 40S FROM LARNED TO DODGE CITY TO LIBERAL, AND TO THE UPPER 40S IN THE COLDWATER AND MEDICINE LODGE AREAS. THAT 2ND COLD FRONT PASSING THROUGH DURING THE EARLY MORNING HOURS WILL USHER IN COLD AIR. THE STRONG NORTH TO NORTHWEST WINDS WILL PERSIST INTO THE MID AFTERNOON. EVEN THOUGH JUST A FEW CLOUDS WILL BE PASSING AND SKIES WILL REMAIN MOSTLY SUNNY, TEMPERATURES WILL STILL STRUGGLE TO RISE IN THE COLD AIR MASS. HIGHS ON FRIDAY WILL ONLY REACH AROUND THE 60F DEGREE MARK FRIDAY NORTHWEST OF A JOHNSON CITY TO GARDEN CITY TO HAYS LINE. WINDS WILL DROP OFF TOWARD SUNSET AS THE PRESSURE GRADIENT FALLS, AND TEMPERATURES WILL DROP RAPIDLY DURING FRIDAY EVENING. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 248 PM CDT THU OCT 2 2014 MEDIUM RANGE MODELS INDICATE A DEEP UPPER LEVEL TROUGH OF LOW PRESSURE SHIFTING EASTWARD ACROSS THE UPPER MIDWEST AND THE GREAT LAKES REGION SATURDAY WHILE A NORTHWESTERLY FLOW ALOFT DEVELOPS ACROSS THE WESTERN HIGH PLAINS. ALTHOUGH A SERIES OF H5 VORT MAXIMA WILL CONTINUE TO CYCLE SOUTHEAST ACROSS THE NORTHERN PLAINS INTO THE TROUGH AXIS ACROSS THE UPPER MIDWEST THROUGH EARLY NEXT WEEK, A NUMBER OF WEAK FRONTAL PASSAGES ASSOCIATED WITH THE SHORTWAVES WILL HELP USHER SURGES OF DRIER AIR SOUTHWARD INTO WESTERN KANSAS. AS A RESULT, PRECIP IS NOT EXPECTED ACROSS THE AREA THROUGH AT LEAST MONDAY. ARCTIC HIGH PRESSURE SLIDING SOUTHEASTWARD ACROSS THE NORTHERN PLAINS INTO THE HIGH PLAINS OF WESTERN KANSAS WILL HELP REINFORCE THE COOLER AIR MASS ALREADY IN PLACE ACROSS THE REGION FRIDAY NIGHT. THE GFS/ECMWF SHOW H85 TEMPERATURES AROUND 5C IN CENTRAL KANSAS WITH THE 0C ISOTHERM WELL OFF TO THE NORTHEAST IN EASTERN NEBRASKA AND NORTHEASTERN KANSAS. ADDITIONALLY, THE MODELS INDICATE A LEE SIDE TROUGH BEGINNING TO DEVELOP BY EARLY SATURDAY MORNING TURNING LIGHT SURFACE WINDS MORE WEST TO SOUTHWESTERLY ACROSS EXTREME SOUTHWEST KANSAS WHERE H85 TEMPERATURES ARE EXPECTED TO REMAIN CLOSER TO 10C. WITH THE HELP OF A DOWNSLOPE FLOW, LOW TEMPERATURES WILL REMAIN WELL ABOVE FREEZING IN EXTREME SOUTHWEST KANSAS AND ALONG THE OKLAHOMA BORDER WITH LOWS NEAR 40F. HOWEVER, LOWS ARE EXPECTED TO FALL INTO THE MID TO UPPER 30(F) IN CENTRAL KANSAS WITH AREAS OF PATCHY FROST POSSIBLE NEAR THE I-70 CORRIDOR. LEE SIDE TROUGHING WILL STRENGTHEN SOMEWHAT SATURDAY ENHANCING THE SOUTHWESTERLY FLOW ACROSS EXTREME SOUTHWEST KANSAS DRAWING WARMER AIR BACK INTO PORTIONS OF WESTERN KANSAS. HOWEVER, MUCH COOLER AIR IS EXPECTED TO REMAIN LOCKED IN ACROSS EASTERN AND PORTIONS OF CENTRAL KANSAS RESULTING IN A TIGHT TEMPERATURE GRADIENT EAST TO WEST ACROSS THE STATE. THE GFS/ECMWF SHOW H85 TEMPERATURES SLOWLY REACHING UP NEAR 10C ACROSS CENTRAL KANSAS TOWARD MID SATURDAY AFTERNOON WITH H85 TEMPERATURES A LITTLE ABOVE 15C IN EXTREME SOUTHWEST KANSAS. LOOK FOR HIGHS EASILY UP INTO THE 70S(F) ACROSS FAR SOUTHWEST KANSAS SATURDAY AFTERNOON WITH TEMPERATURES STRUGGLING TO REACH THE 70S(F), IF AT ALL, IN CENTRAL KANSAS NEAR THE I-70 CORRIDOR DEPENDING WHERE THE GRADIENT SETS UP. A GRADUAL WARMING TREND WILL THEN PROCEED INTO EARLY NEXT WEEK AS A NORTHWEST FLOW ALOFT SETS UP ACROSS THE WESTERN HIGH PLAINS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1210 PM CDT THU OCT 2 2014 OVERALL, WE EXPECT VFR CONDITIONS, WITH KHYS BECOME VFR FROM MVFR BY 20Z. AS A COLD FRONT EXITS EAST OF THE TAF AREAS, SKIES WILL BECOME CLEAR AND NORTHWEST WINDS WILL BLOW AT 20G30KTS THROUGH 00Z. WINDS SHOULD THEN BECOME LIGHT AND VARIABLE AS THE SUNDOWN APPROACHES. ANOTHER COLD FRONT WILL ZIP DOWN FROM WYOMING FRIDAY MORNING, AND WINDS WILL PICK BACK UP FROM THE NORTHWEST AT 19G25KT. && .PRELIMINARY POINT TEMPS/POPS... DDC 44 62 38 73 / 0 0 0 0 GCK 42 61 37 74 / 0 0 0 0 EHA 43 62 40 75 / 0 0 0 0 LBL 44 64 40 75 / 0 0 0 0 HYS 40 60 36 70 / 0 0 0 0 P28 48 65 38 72 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURKE LONG TERM...JJOHNSON AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
200 PM CDT THU OCT 2 2014 ...UPDATE FOR THE SHORT TERM FORECAST... .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 158 PM CDT THU OCT 2 2014 THE FIRST COLD FRONT IS EXITING OUR EASTERN TIER OF COUNTIES AS I WRITE THIS DISCUSSION. IN THE WEST, CLOUDS HAVE BEEN SCATTERING OUT AND WINDS SUBSIDING SLIGHTLY. BY 22Z, THE WESTERN HALF OF THE CWA SHOULD HAVE CLEARED OUT, AND BY 02Z THE EASTERN HALF. THE PRESSURE GRADIENT WILL SLACKEN NEAR SUNSET, AND WINDS SHOULD GO LIGHT AND VARIABLE EVERYWHERE BY THAT TIME. NORMALLY, WITH RECENT RAINS AND LIGHT WINDS, I AT FIRST CONSIDERED PUTTING IN SOME MENTION OF FOG LATE TONIGHT. BUT THEN I REALIZED ANOTHER COLD FRONT WILL SWEEP THROUGH PRIOR TO SUNRISE FRIDAY. WINDS BEHIND THE OVERNIGHT FRONTAL PASSAGE WILL SWITCH AROUND TO THE NORTH AT 18G28KT, THUS NEGATING THE CHANCE FOR FOG DEVELOPMENT. LOWS TONIGHT ARE VERY CLOSE TO WHAT THE NAMDNG25 AND RAP MODELS ARE FORECASTING, RANGING FROM NEAR 40F DEGREES IN WAKEENEY, SCOTT CITY AND SYRACUSE, TO THE MID 40S FROM LARNED TO DODGE CITY TO LIBERAL, AND TO THE UPPER 40S IN THE COLDWATER AND MEDICINE LODGE AREAS. THAT 2ND COLD FRONT PASSING THROUGH DURING THE EARLY MORNING HOURS WILL USHER IN COLD AIR. THE STRONG NORTH TO NORTHWEST WINDS WILL PERSIST INTO THE MID AFTERNOON. EVEN THOUGH JUST A FEW CLOUDS WILL BE PASSING AND SKIES WILL REMAIN MOSTLY SUNNY, TEMPERATURES WILL STILL STRUGGLE TO RISE IN THE COLD AIR MASS. HIGHS ON FRIDAY WILL ONLY REACH AROUND THE 60F DEGREE MARK FRIDAY NORTHWEST OF A JOHNSON CITY TO GARDEN CITY TO HAYS LINE. WINDS WILL DROP OFF TOWARD SUNSET AS THE PRESSURE GRADIENT FALLS, AND TEMPERATURES WILL DROP RAPIDLY DURING FRIDAY EVENING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 234 AM CDT THU OCT 2 2014 A SIGNIFICANT LARGE SCALE TROUGH WILL GRIP THE UPPER MIDWEST/GREAT LAKES REGION GOING INTO THIS WEEKEND. WE WILL SEE ANOTHER FRONTAL PASSAGE EARLY FRIDAY, USHERING IN A MUCH COOLER CANADIAN AIRMASS. WIND GRIDS WERE BUMPED UP EARLY FRIDAY MORNING THROUGH MIDDAY GIVEN THE FAIRLY INTENSE ISALLOBARIC PUSH WITH THE ONSET OF THE FRONT. WE WILL LIKELY SEE A 2 TO 4 HOUR PERIOD OF SUSTAINED WINDS OF 30+ MPH AND GUSTS AROUND 45 MPH. THE WINDS WILL DECREASE SLOWLY THROUGH THE DAY, BUT NORTHWEST WINDS OF 20 TO 25 MPH WILL STILL EXIST THROUGH THE MID TO LATE AFTERNOON HOURS. WE LOWERED THE HIGH TEMPERATURE FORECAST TO AROUND 60 FROM SCOTT CITY TO WAKEENEY TO HAYS AND 63-65F ALONG THE OKLAHOMA BORDER. AS WE HEAD INTO FRIDAY NIGHT, WINDS WILL DECREASE FURTHER AS HIGH PRESSURE RIDGE SETTLES IN FROM THE NORTHWEST. FRIDAY NIGHT IS LOOKING MORE AND MORE LIKE AN IDEAL NIGHT FOR MAXIMIZED RADIATIONAL COOLING WITH WINDS DECREASING TO 6 KNOTS OR LESS AFTER MIDNIGHT ALONG WITH MOSTLY CLEAR SKIES. WE LOWERED OVERNIGHT LOWS A COUPLE MORE DEGREES TO 36-38F UP NORTH AND ADDED IN PATCHY FROST FOR THE AREAS FORECAST 36F OR COOLER, PARTICULARLY ALONG INTERSTATE 70. THE LONGWAVE PATTERN WILL REMAIN NEARLY UNCHANGED, ON THE WHOLE, THROUGH EARLY NEXT WEEK, BUT THE NORTHWEST FLOW WILL EVENTUALLY BECOME MORE WEST-NORTHWESTERLY AND GREATER DOWNSLOPE COMPONENT, LEADING TO A NICE MODIFICATION OF THE LOWER TROPOSPHERE. WE SHOULD SEE A RETURN TO 80-DEGREE AFTERNOONS BY AS EARLY AS MONDAY, AND ALMOST CERTAINLY BY TUESDAY. THE FORECAST WILL BE DRY WITH LOW LEVEL MOISTURE WIPED OUT FROM THE WEEKEND FRONT AND OVERALL SUBSIDENCE/WEAK FORCING FOR ASCENT THROUGH THE DEPTH OF THE TROPOSPHERE. THERE MAY BE A RETURN TO SOME BETTER PRECIPITATION CHANCES GOING INTO LATE NEXT WEEK, BUT THE OFFICIAL FORECAST THROUGH THURSDAY OF NEXT WEEK WILL BE DRY ACROSS THE ENTIRE SOUTHWEST, WEST- CENTRAL, SOUTH-CENTRAL KANSAS REGION. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1210 PM CDT THU OCT 2 2014 OVERALL, WE EXPECT VFR CONDITIONS, WITH KHYS BECOME VFR FROM MVFR BY 20Z. AS A COLD FRONT EXITS EAST OF THE TAF AREAS, SKIES WILL BECOME CLEAR AND NORTHWEST WINDS WILL BLOW AT 20G30KTS THROUGH 00Z. WINDS SHOULD THEN BECOME LIGHT AND VARIABLE AS THE SUNDOWN APPROACHES. ANOTHER COLD FRONT WILL ZIP DOWN FROM WYOMING FRIDAY MORNING, AND WINDS WILL PICK BACK UP FROM THE NORTHWEST AT 19G25KT. && .PRELIMINARY POINT TEMPS/POPS... DDC 44 62 38 76 / 0 0 0 0 GCK 42 61 37 76 / 0 0 0 0 EHA 43 62 40 76 / 0 0 0 0 LBL 44 64 40 77 / 0 0 0 0 HYS 40 60 36 71 / 0 0 0 0 P28 48 65 39 76 / 0 0 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURKE LONG TERM...UMSCHEID AVIATION...BURKE
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
414 PM EDT THU OCT 2 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 329 PM EDT THU OCT 2 2014 TWO UPPER TROUGH CURRENTLY W OF THE REGION /ONE OVER THE PLAINS AND ANOTHER MOVING INTO MT/ WILL COMBINE THIS EVENING INTO TONIGHT WHILE BECOMING NEGATIVELY TILTED. THIS WILL ENHANCE AND MOVE THE UPPER JET CURRENTLY OVER THE CWA TO THE N...WHICH WILL PUT THE CWA UNDER THE RIGHT ENTRANCE REGION TONIGHT INTO EARLY FRI MORNING. THIS WILL DEEPEN THE 1006MB SFC LOW CURRENTLY OVER THE CENTRAL PLAINS TO ROUGHLY 996MB LOW WHILE IT MOVES TO NEAR GRB BY 06Z FRI AND 991MB OVER ERN LAKE SUPERIOR BY 12Z FRI. THE SFC LOW WILL THEN DEEPEN TO AROUND 985MB AS IT MOVES TO NEAR JAMES BAY BY 00Z SAT AS THE UPPER TROUGH DEEPENS INTO A CLOSED LOW AND MOVES INTO WRN WI. MODEL AGREEMENT IS GOOD BETWEEN ALL BUT THE ECMWF...WHICH IS SLOWER...WEAKER AND FARTHER E. DID NOT USE THE ECMWF DUE TO IT BEING AN OUTLIER. PRECIP WILL MOVE INTO THE AREA THIS EVENING AS THE LOW MOVES UP AND JET FORCING IMPROVES...WITH SOME MODERATE TO HEAVY RAIN AND POSSIBLY THUNDER DUE TO THE STRENGTH OF THE FORCING AND 100-200J/KG OF ELEVATED CAPE. HAVE 100 POPS SLOWLY MOVING SW TO NE LATE THIS EVENING THROUGH FRI MORNING. ONLY SCATTERED TO ISOLATED RAIN SHOWERS ARE EXPECTED BEHIND THE MAIN AREA OF PRECIP FRI AS THE DRY SLOT ROTATES INTO THE AREA. BY MID AFTERNOON FRI...COOLER WESTERLY LOW LEVEL WINDS WILL FAVOR THE HIGHER TERRAIN OF WRN UPPER MI FOR THE BEST PRECIP...ALONG WITH COOLING SFC TEMPS. TOTAL QPF AMOUNTS TONIGHT AND FRI LOOK TO BE ABOVE 1 INCH IN MOST LOCATIONS...WITH 0.75 INCHES AT IWD AND 1.5 INCHES AT ERY IN THE FORECAST. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 410 PM EDT THU OCT 2 2014 MAIN FCST CONCERNS IN THE LONGER TERM REVOLVE ARND POPS FOR LAKE EFFECT PCPN/POTENTIAL FOR SOME SN ACCUMULATION THRU THE WEEKEND AS CHILLY...DEEP CYC NW FLOW ARND CLOSED LO IN ONTARIO THAT IS FCST TO DOMINATE THE UPR LKS INTO EARLY NEXT WEEK. MAX TEMPS WL BE PARTICULARLY BLO NORMAL THRU THIS PERIOD. A RETURN TO A MORE ZONAL FLOW THE SECOND HALF OF NEXT WEEK WL BRING BACK MORE SEASONABLE CONDITIONS. FRI NGT...A SHRTWV DIGGING INTO THE DEEPENING UPR TROF IN THE GREAT LKS IS FCST TO DRAG A REINFORCING COLD FNT ACRS UPR MI AND DROP H85 TEMPS AS LO AS -3 TO -4C OVER THE W BY 12Z SAT. WHILE THERE WL BE SOME SHOWERS AHEAD OF THE COLD FNT WITH ENHANCED LLVL CNVGC UNDER AREA OF DEEP LYR QVECTOR CNVGC...THE STRENGTHENING CYC FLOW W VEERING NW LLVL FLOW IN THE PRESENCE OF THE DYNAMIC FORCING/COOLING LLVL TEMPS WL RESULT IN LK ENHANCED PCPN LATER AT NGT FOLLOWING THE FROPA...ESPECIALLY IN AREAS OVER THE W DOWNWIND OF LK SUP FAVORED BY THE FCST LLVL FLOW. SINCE THE GREAT MAJORITY OF THE MODELS SHOW H100-85 THKNS REMAINING OVER 1305M THRU 12Z SAT AND LLVL LAPSE RATES ARE RATHER UNSTABLE...THIS PCPN WL BE IN THE FORM OF RA. A FEW OF THE HIER ELEVATION LOCATIONS COULD SEE SOME SN MIX WITH THE PCPN LATE...BUT NO ACCUMS ARE LIKELY. SAT THRU MON NGT...A DEEP UPR LO IS FCST TO CONSOLIDATE OVER NW ONTARIO DURING THIS TIME AS MYRIAD OF SHRTWVS PASSING THRU THE UPR TROF PHASE AND LOWER HGTS AT THE CENTER OF THE UPR LO. A DEEP CYC FLOW ON THE SRN FLANK OF THIS FEATURE IS FCST TO DOMINATE THE UPR LKS...WITH H85 TEMPS FCST TO DIP AS LO AS ABOUT -5C LATE SAT/SUN OVER THE N UNDER ASSOCIATED THERMAL TROF. WHILE THIS SETUP IS FAVORABLE FOR LK EFFECT/ENHANCED SHOWERS...TIMING ON THE PASSAGE OF THE SHRTWVS AND PERIODS WHERE THE MSTR WL BE DEEPEST AND EXTEND THRU THE -10C ISOTHERM TO PINPOINT PERIODS OF HEAVIER/MORE WIDESPREAD SHOWERS WL BE DIFFICULT. ALTHOUGH SOME SN WL LIKELY MIX WITH THE PCPN OVER MAINLY THE HIER TERRAIN OF THE W AND NCENTRAL...FCST H100-85 THKNS AOA 1305M MOST OF THE TIME IN AREAS MOST PRONE TO THE LK EFFECT PCPN DOWNWIND OF THE LK SUGGESTS THE SN WL BE LIMITED. THE BEST CHC FOR SN TO MIX WITH THE PCPN WL BE SAT NGT/SUN MRNG OVER THE INTERIOR NW...WHEN THE H85 TEMPS/THKNS ARE LOWEST. THE CYC FLOW IS FCST TO BACK SLOWLY THRU THE PERIOD FM THE NNW ON SAT MRNG TO THE W LATER ON SUN AND MON...SHIFTING THE LOCATION OF EXPECTED HIER POPS/MORE NMRS LK EFFECT SHOWERS. STRONGER WINDS ON SAT/SUN WITH H925 WINDS UP TO 30-35KTS ARE FCST TO DIMINISH BY MON AS THE UPR LO BEGINS TO WEAKEN AND LIFT SLOWLY TO THE N. TEMPS WL RUN BLO NORMAL TO WELL BLO NORMAL...ESPECIALLY THE DAYTIME MAX TEMPS. AS THE FLOW BACKS TO THE W...LESS MODIFIED AIR WL BRING COLDER OVERNGT LO TEMPS NEAR THE WI BORDER. WITH A LENGTHY PERIOD OF STRONG NW TO W WINDS ON LAKE SUP... INCLUDING GALES FOR A TIME...AND HI LAKE LEVELS (LAKE SUP IS CURRENTLY ABOUT 6 INCHES BLO THE RECORD HI FOR THIS TIME OF YEAR)... BEACH EROSION/FLOODING MAY BECOME A PROBLEM FOR AREAS THAT ARE EXPOSED TO WAVES GENERATED BY W TO NW WINDS. WILL CONTINUE TO HIGHLIGHT THIS POTENTIAL HAZARD IN THE HWO/EHWO. TUE THRU THU...AS THE CENTER OF LOWER HGTS TENDS TO SHIFT INTO CENTRAL CANADA FOLLOWING THE PASSAGE OF A FINAL SHRTWV THRU THE UPR LKS MON NGT/TUE...THE FLOW OVER THE THE AREA IS PROGGED TO BECOME MORE ZONAL AS HGTS SLOWLY RISE. THIS TRANSITION WL CAUSE LINGERING PCPN ON TUE TO DIMINISH AS MAINLY DAYTIME TEMPS WARM. TIMING OF DISTURBANCES MOVING THRU THE MORE ZONAL FLOW AND ASSOCIATED PCPN SUGGESTS FOLLOWING A MODEL CONSENSUS FOR POPS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 141 PM EDT THU OCT 2 2014 AS NEXT SYSTEM APPROACHES THIS EVENING...CONDITIONS WILL RAPIDLY DETERIORATE TO IFR/LIFR WITH UPSLOPE RAIN AND FOG. UTILIZED A NEARLY EVEN BLEND OF CONSENSUS SHORT TERM GUIDANCE AND THE HRRR OVER THE NEXT FEW HOURS...THEN CONSENSUS GUIDANCE WEIGHTED MORE HEAVILY TOWARD THE HIGH-RES WRF AND NAM TONIGHT INTO FRIDAY. EXPECT WORST CONDITIONS TONIGHT...FOLLOWED BY SLOW IMPROVEMENT FRI MORNING AS THE LOW AND ASSOCIATED LOW LEVEL MOISTURE MOVES NE OF THE AREA. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 410 PM EDT THU OCT 2 2014 EXPECT LIGHT WINDS THROUGH MOST OF TONIGHT AS A SURFACE LOW MOVES FROM THE UPPER MIDWEST TO THE NORTH ACROSS UPPER MI INTO LK SUPERIOR. ONCE THE LOW LIFTS TO THE NORTH OF LK SUPERIOR ON FRI...WINDS WILL SHIFT TO THE W-NW AND INCREASE UP TO 25-30 KTS. STILL LOOKING FOR GALE FORCE W VEERING N WINDS TO DEVELOP ON FRI NIGHT ASSOCIATED WITH A REINFORCING COLD FRONTAL PASSAGE AND SURGE OF COLDER AIR OVER THE RELATIVELY WARM WATERS. SINCE THE WINDS ON FRI AFTERNOON ARE NOT EXPECTED TO BE AS STRONG AS BEFORE...OPTED TO SHIFT THE START OF THE GALE WATCH TO FRI EVENING. THE STRONG-GALE FORCE NNW WINDS ON SAT MORNING WILL BACK TOWARD THE W AND DIMINISH BY LATE IN THE DAY AS THE PRES GRADIENT SLOWLY RELAXES OVER THE UPPER GREAT LAKES. AS A LOW PRESSURE SYSTEM OVER NW ONTARIO SHIFTS TO THE N AND WEAKENS LATER IN THE WEEKEND INTO EARLY NEXT WEEK... THE WINDS WILL CONTINUE TO SLOWLY BACK TOWARD THE SW AND WEAKEN A BIT. DEPENDING ON THE TRACK OF A LOW PRESSURE SYSTEM ON TUE...THE WINDS MAY VEER BACK TOWARD THE W AND INCREASE AGAIN. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM SATURDAY MORNING THROUGH SATURDAY AFTERNOON FOR LSZ267. GALE WATCH FROM FRIDAY EVENING THROUGH SATURDAY AFTERNOON FOR LSZ263>266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...TITUS LONG TERM...KC AVIATION...TITUS MARINE...KC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
331 PM EDT THU OCT 2 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 329 PM EDT THU OCT 2 2014 TWO UPPER TROUGH CURRENTLY W OF THE REGION /ONE OVER THE PLAINS AND ANOTHER MOVING INTO MT/ WILL COMBINE THIS EVENING INTO TONIGHT WHILE BECOMING NEGATIVELY TILTED. THIS WILL ENHANCE AND MOVE THE UPPER JET CURRENTLY OVER THE CWA TO THE N...WHICH WILL PUT THE CWA UNDER THE RIGHT ENTRANCE REGION TONIGHT INTO EARLY FRI MORNING. THIS WILL DEEPEN THE 1006MB SFC LOW CURRENTLY OVER THE CENTRAL PLAINS TO ROUGHLY 996MB LOW WHILE IT MOVES TO NEAR GRB BY 06Z FRI AND 991MB OVER ERN LAKE SUPERIOR BY 12Z FRI. THE SFC LOW WILL THEN DEEPEN TO AROUND 985MB AS IT MOVES TO NEAR JAMES BAY BY 00Z SAT AS THE UPPER TROUGH DEEPENS INTO A CLOSED LOW AND MOVES INTO WRN WI. MODEL AGREEMENT IS GOOD BETWEEN ALL BUT THE ECMWF...WHICH IS SLOWER...WEAKER AND FARTHER E. DID NOT USE THE ECMWF DUE TO IT BEING AN OUTLIER. PRECIP WILL MOVE INTO THE AREA THIS EVENING AS THE LOW MOVES UP AND JET FORCING IMPROVES...WITH SOME MODERATE TO HEAVY RAIN AND POSSIBLY THUNDER DUE TO THE STRENGTH OF THE FORCING AND 100-200J/KG OF ELEVATED CAPE. HAVE 100 POPS SLOWLY MOVING SW TO NE LATE THIS EVENING THROUGH FRI MORNING. ONLY SCATTERED TO ISOLATED RAIN SHOWERS ARE EXPECTED BEHIND THE MAIN AREA OF PRECIP FRI AS THE DRY SLOT ROTATES INTO THE AREA. BY MID AFTERNOON FRI...COOLER WESTERLY LOW LEVEL WINDS WILL FAVOR THE HIGHER TERRAIN OF WRN UPPER MI FOR THE BEST PRECIP...ALONG WITH COOLING SFC TEMPS. TOTAL QPF AMOUNTS TONIGHT AND FRI LOOK TO BE ABOVE 1 INCH IN MOST LOCATIONS...WITH 0.75 INCHES AT IWD AND 1.5 INCHES AT ERY IN THE FORECAST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 523 AM EDT THU OCT 2 2014 THE FIRST HALF OF THE LONG TERM WILL BE DOMINATED BY A DEEP TROF THAT WILL BE DEVELOPING OVER THE ERN CONUS OVER THE NEXT FEW DAYS. IMPRESSIVE HEIGHT ANOMALIES MAX OUT OVER THE LOWER OHIO VALLEY EARLY ON SAT WHERE 500MB HEIGHTS WILL BE 3.5 STANDARD DEVIATIONS BLO THE LONG TERM EARLY OCT AVG. TROF WILL EVOLVE INTO A LARGE MID-LEVEL LOW CENTERED OVER NRN ONTARIO FROM LATE SAT THRU THE EARLY PART OF NEXT WEEK. THIS PATTERN WILL BRING A BLO NORMAL TEMP REGIME. DAILY MAX TEMPS WILL BE THE MOST ANOMALOUS WITH MANY DAYS HAVING HIGHS WELL BLO NORMAL. AS WOULD BE EXPECTED...THE WEATHER WILL BE UNSETTLED WITH LAKE EFFECT/LAKE ENHANCED PCPN UNDER COLD DEEP CYCLONIC FLOW. AIR MASS WILL BE COLD ENOUGH TO SUPPORT SNOW AT TIMES OVER THE HIGHER TERRAIN WITH SOME LIGHT ACCUMULATIONS CERTAINLY POSSIBLE...NOT THAT UNUSUAL FOR EARLY OCT. FARTHER OUT...MEDIUM RANGE GUIDANCE HAS COME INTO BETTER AGREEMENT ON TIMING THE TRANSITION TO A MORE PROGRESSIVE/LESS AMPLIFIED FLOW DURING THE MIDDLE AND END OF NEXT WEEK. THIS WILL LEAD TO MODERATION OF TEMPS BACK CLOSER TO NORMAL AFTER A COLD EARLY PART OF THE WEEK. BEGINNING FRI...SFC LOW WILL BE LIFTING N THRU ERN LAKE SUPERIOR DURING THE MORNING. MDT TO POSSIBLY HVY RAINFALL THAT OVERSPREADS THE AREA TONIGHT WILL LINGER OVER THE E THRU AT LEAST THE MORNING HRS AS A RESULT OF ANOTHER SHORTWAVE LIFTING N THRU LWR MI. ECMWF REMAINS SLOWER THAN OTHER MODELS SHIFTING THIS RAIN OUT OF THE ERN FCST AREA FRI. IN THE WAKE OF THE MAIN PCPN AREA...A MORE SHOWERY PCPN REGIME WILL TAKE OVER...BUT WITH MID LEVEL DRYING NOTED...A GOOD PART OF THE DAY MAY ACTUALLY END UP DRY OVER PORTIONS OF THE W AND CNTRL. WINDS WILL INCREASE AND TURN GUSTY...ESPECIALLY ACROSS LAKE SUPERIOR AND THE KEWEENAW UNDER A FAVORABLE WRLY WIND FLOW. FRI NIGHT...MODELS ARE IN PRETTY GOOD AGREEMENT THAT A REINFORCING SECOND COLD FRONT WILL DROP THRU THE AREA BRINGING COLDER AIR MORE FIRMLY INTO THE UPPER LAKES...WITH 850MB TEMPS DROPPING TO -2 TO -4C BY 12Z SAT. IN CONCERT WITH FAIRLY STRONG DEEP LAYER QVECTOR CONVERGENCE THAT IS PROGGED TO SHIFT ACROSS THE AREA...LAKE ENHANCED SHOWERS WILL INCREASE. WETBULB ZERO HEIGHTS SUPPORT THE POTENTIAL FOR PCPN TO MIX WITH OR EVEN CHANGE TO SNOW OVER THE HIGH TERRAIN OF FAR W THE NEAR THE WI BORDER. OVER THE WEEKEND...DEEP...CHILLY AND MOIST CYCLONIC FLOW WILL DOMINATE AS MID/UPPER LEVEL LOW SPINS OVER NRN ONTARIO. WITH 850MB TEMPS IN THE -3 TO -6C RANGE...EXPECT PLENTY OF CLOUDS AND LAKE EFFECT PCPN. SHORTWAVES ROTATING AROUND THE LOW WILL BRING PERIODS OF HEAVIER/MORE WIDESPREAD LAKE ENHANCED PCPN. PCPN ON SAT WILL BE MOST FAVORED IN AREAS AFFECTED BY NW FLOW LAKE EFFECT. BACKING WINDS ON SUN WILL SHIFT PCPN TO AREAS THAT ARE MOST AFFECTED BY WESTERLY FLOW LAKE EFFECT. RAIN WILL MIX WITH OR CHANGE TO SNOW AT TIMES OVER THE HIGHER TERRAIN...ESPECIALLY DURING THE NIGHT AND MORNING HRS. WITH A LENGTHY PERIOD OF STRONG NW TO W WINDS ON LAKE SUPERIOR... INCLUDING GALES FOR A TIME...AND HIGH LAKE LEVELS (LAKE SUPERIOR IS CURRENTLY ABOUT 6 INCHES BLO THE RECORD HIGH FOR THIS TIME OF YEAR)...BEACH EROSION/FLOODING MAY BECOME A PROBLEM FOR AREAS THAT ARE EXPOSED TO WAVES GENERATED BY W TO NW WINDS. AS MENTIONED AT THE BEGINNING OF THIS DISCUSSION THERE IS MUCH BETTER AGREEMENT ON TRANSITIONING FLOW DURING THE MIDDLE AND END OF NEXT WEEK. AGREEMENT IS GOOD THAT THE MID LEVEL LOW WILL LINGER OVER NRN ONTARIO THRU AT LEAST MON...WHICH WILL KEEP THE UPPER LAKES UNDER ITS UNSETTLED INFLUENCE. LOW WILL BEGIN TO LIFT OUT TUE... LEADING TO A TRANSITION TO DRY WEATHER AND SOME TEMP MODERATION. MODERATION/DRY WEATHER WILL CONTINUE WED WITH A MORE ZONALLY ORIENTED FLOW TAKING SHAPE ACROSS THE NRN CONUS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 141 PM EDT THU OCT 2 2014 AS NEXT SYSTEM APPROACHES THIS EVENING...CONDITIONS WILL RAPIDLY DETERIORATE TO IFR/LIFR WITH UPSLOPE RAIN AND FOG. UTILIZED A NEARLY EVEN BLEND OF CONSENSUS SHORT TERM GUIDANCE AND THE HRRR OVER THE NEXT FEW HOURS...THEN CONSENSUS GUIDANCE WEIGHTED MORE HEAVILY TOWARD THE HIGH-RES WRF AND NAM TONIGHT INTO FRIDAY. EXPECT WORST CONDITIONS TONIGHT...FOLLOWED BY SLOW IMPROVEMENT FRI MORNING AS THE LOW AND ASSOCIATED LOW LEVEL MOISTURE MOVES NE OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 444 AM EDT THU OCT 2 2014 EXPECT DIMINISHING S WINDS THIS MORNING OVER THE EAST. WINDS WILL REMAIN LIGHT THROUGH MOST OF TONIGHT AS SFC LOW TO THE NORTH ACROSS LK SUPERIOR. ONCE THE LOW LIFTS TO THE NORTH OF LK SUPERIOR ON FRIDAY...STRONG WEST WINDS WILL SPREAD ACROSS LK SUPERIOR DUE TO TIGHT PRESSURE GRADIENT AND THE ARRIVAL OF COLDER AIR. GALE FORCE WINDS EXPECTED LATER FRIDAY AFTN...AND THESE WILL INCREASE TO 35-40 KTS FRIDAY NIGHT INTO SATURDAY AS WINDS SHIFT TO THE NORTHWEST AS COLDER AIR MOVES ACROSS LK SUPERIOR. GALE WATCH IN EFFECT FOR ALL BUT FAR WESTERN LK SUPERIOR FRIDAY AFTERNOON THROUGH EARLY SATURDAY AFTERNOON. AS IT STANDS NOW...GALE WARNINGS WILL EVENTUALLY BE ISSUED EITHER LATER TODAY OR TONIGHT. THOUGH GALES SHOULD DIMINISH ON SATURDAY AFTERNOON...WEST WINDS 20-30 KTS WILL PERSIST INTO SUNDAY AND SUNDAY NIGHT WITH GUSTY SOUTHWEST WINDS EXPECTED MONDAY INTO TUESDAY OUT AHEAD OF ANOTHER LOW PRESSURE SYSTEM DROPPING IN FROM SCNTRL CANADA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY AFTERNOON FOR LSZ263>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...TITUS LONG TERM...ROLFSON AVIATION...TITUS MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
142 PM EDT THU OCT 2 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 444 AM EDT THU OCT 2 2014 DESPITE THE SOUTHERLY FLOW IN LOW-LEVELS...MAIN WARM FRONT IS WELL TO SOUTH OVER CNTRL MISSISSIPPI RIVER VALLEY. FRONT ESSENTIALLY IS JUST TO SOUTH OF WHERE MULTIPLE CLUSTERS OF TSRA ARE CURRENTLY OCCURRING. STRONG LOW PRESSURE OVER NORTHERN MANITOBA MOVING TOWARD HUDSON BAY AND A NORTH-SOUTH ORIENTED FRONT FROM THE LOW TOWARD THE UPPER MISSISSIPPI RIVER VALLEY IS REASON FOR THE SOUTH WINDS OVER UPR LAKES REGION. SHOWERS HAVE DEVELOPED OVER SOUTHERN AND EASTERN CWA THIS MORNING OUT AHEAD OF SHORTWAVE AND ON NOSE OF JET STREAK OVER WISCONSIN AND WITHIN AREA OF GREATER MOISTURE ADVECTION. THERE IS ALSO A TOUCH OF MID-LEVEL INSTABILITY BUT NO TSRA HAVE BEEN OBSERVED THUS FAR. EXPECT SHRA OVER MAINLY EASTERN CWA INTO AT LEAST EARLY AFTN WHILE REST OF CWA SHOULD BE WITHIN A LULL AS MUCH STRONGER SYSTEM IN FORM OF TWO MAIN SHORTWAVES...ONE OVER FOUR CORNERS AND THE OTHER STRONGER ONE OVER WESTERN CANADA DIVING SOUTHEAST OVER SOUTHERN BRITISH COLUMBIA AND ALBERTA...DOES NOT BEGIN TO AFFECT UPPER GREAT LAKES UNTIL LATER THIS AFTN AND MORE EMPHATICALLY INTO TONIGHT. BACK TO TODAY...EXPECT TEMPS TO END UP A BIT ABOVE NORMAL /NORMAL HIGHS UPR 50S TO LOW 60S/ AS 950-900MB TEMPS CONTINUE TO WARM AHEAD OF LARGER SCALE UPPER TROUGH OVER WESTERN CANADA AND ROCKIES AND CLOUD COVER BY AFTN SHOULD THIN OUT SOME. EXPECT MAX TEMPS INTO THE 60S...WITH SHOT AT EVEN SOME UPPER 60S FOR SOME LOCATIONS OVER WEST HALF OF CWA. INTO THIS EVENING THE WESTERN CANADA SHORTWAVE DIVES ACROSS NORTHERN PLAINS WHILE THE FOUR CORNERS WAVE HEADS ACROSS KS INTO WESTERN MO. OVERNIGHT THE NORTHERN PLAINS SHORTWAVE WILL BECOME THE MAIN SHORTWAVE AS IT PHASES WITH THE SOUTHERN PLAINS WAVE. LIFT WILL INCREASE DUE TO DEEPENING OF LARGER SCALE TROUGH FROM SCNTRL CANADA TO SOUTHERN PLAINS/12 HR HEIGHT FALLS UP TO 150DAM SPREADING TOWARD UPPER GREAT LAKES AND BROAD MODERATE/STRONG H7-H5 Q-VECTOR CONVERGENCE OVER UPR GREAT LAKES. ENHANCEMENT TO LIFT AS H3 JET STREAK AMPLIFIES FM UPPER GREAT LAKES TO NORTHERN ONTARIO/HUDSON BAY...PLACING MUCH OF UPR MICHIGAN WITHIN RIGHT ENTRANCE REGION. WITH THE BACKGROUND OF THIS LARGER SCALE SUPPORT...STRONG SSW-NNE MOISTURE ADVECTION RAMPS UP AHEAD OF THE INITIAL NORTH-SOUTH ORIENTED SFC TROUGH AND AS WAVE OF SFC LOW PRESSURE THAT IS FORMING OVER SOUTHERN PLAINS THIS MORNING STEADILY DEEPENS AS IT LIFTS ALONG TROUGH TO A POSITION SOMEWHERE VCNTY OF EASTERN LK SUPERIOR BY DAYBREAK FRIDAY. OVERALL...CONSENSUS OF MODEL GUIDANCE AND EXPECTED FORCING AND MOISTURE ADVECTION SUPPORTS LARGE SHIELD OF MODERATE RAIN LIFTING ACROSS UPR MICHIGAN THIS EVENING AND CONTINUING THOUGH MOST OF THE NIGHT. QPF AMOUNTS SEEM LIKELY TO REACH 0.75 INCHES OVER EAST CWA...WHILE AMOUNTS SHOULD STAY BLO 0.50 INCH OVER WEST CWA AS THAT AREA IS FARTHER REMOVED FM ADVECTION OF MOISTURE WITH PWATS OVER 200 PCT OF NORMAL. STRENGTH OF DYNAMICS SUGGESTS SOME EMBEDDED TSRA MAY OCCUR...THOUGH BEST CHANCE WILL BE OVER EAST HALF OF CWA LATER THIS EVENING AND OVERNIGHT CLOSER TO STRONGER H85-H7 MOISTURE TRANSPORT AND TRACK OF DEEPENING SFC LOW. EVEN WITH THE DEEPENING LOW MOVING ACROSS TONIGHT...APPEARS STRONGER WINDS WILL NOT MATERIALIZE UNTIL MORE SO ON FRIDAY. MINS TONIGHT WILL BE ON THE MILD SIDE FOR EARLY OCTOBER...WITH NEAR 50 DEGREE READINGS WEST TO MID-UPR 50S FOR THE EAST. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 523 AM EDT THU OCT 2 2014 THE FIRST HALF OF THE LONG TERM WILL BE DOMINATED BY A DEEP TROF THAT WILL BE DEVELOPING OVER THE ERN CONUS OVER THE NEXT FEW DAYS. IMPRESSIVE HEIGHT ANOMALIES MAX OUT OVER THE LOWER OHIO VALLEY EARLY ON SAT WHERE 500MB HEIGHTS WILL BE 3.5 STANDARD DEVIATIONS BLO THE LONG TERM EARLY OCT AVG. TROF WILL EVOLVE INTO A LARGE MID-LEVEL LOW CENTERED OVER NRN ONTARIO FROM LATE SAT THRU THE EARLY PART OF NEXT WEEK. THIS PATTERN WILL BRING A BLO NORMAL TEMP REGIME. DAILY MAX TEMPS WILL BE THE MOST ANOMALOUS WITH MANY DAYS HAVING HIGHS WELL BLO NORMAL. AS WOULD BE EXPECTED...THE WEATHER WILL BE UNSETTLED WITH LAKE EFFECT/LAKE ENHANCED PCPN UNDER COLD DEEP CYCLONIC FLOW. AIR MASS WILL BE COLD ENOUGH TO SUPPORT SNOW AT TIMES OVER THE HIGHER TERRAIN WITH SOME LIGHT ACCUMULATIONS CERTAINLY POSSIBLE...NOT THAT UNUSUAL FOR EARLY OCT. FARTHER OUT...MEDIUM RANGE GUIDANCE HAS COME INTO BETTER AGREEMENT ON TIMING THE TRANSITION TO A MORE PROGRESSIVE/LESS AMPLIFIED FLOW DURING THE MIDDLE AND END OF NEXT WEEK. THIS WILL LEAD TO MODERATION OF TEMPS BACK CLOSER TO NORMAL AFTER A COLD EARLY PART OF THE WEEK. BEGINNING FRI...SFC LOW WILL BE LIFTING N THRU ERN LAKE SUPERIOR DURING THE MORNING. MDT TO POSSIBLY HVY RAINFALL THAT OVERSPREADS THE AREA TONIGHT WILL LINGER OVER THE E THRU AT LEAST THE MORNING HRS AS A RESULT OF ANOTHER SHORTWAVE LIFTING N THRU LWR MI. ECMWF REMAINS SLOWER THAN OTHER MODELS SHIFTING THIS RAIN OUT OF THE ERN FCST AREA FRI. IN THE WAKE OF THE MAIN PCPN AREA...A MORE SHOWERY PCPN REGIME WILL TAKE OVER...BUT WITH MID LEVEL DRYING NOTED...A GOOD PART OF THE DAY MAY ACTUALLY END UP DRY OVER PORTIONS OF THE W AND CNTRL. WINDS WILL INCREASE AND TURN GUSTY...ESPECIALLY ACROSS LAKE SUPERIOR AND THE KEWEENAW UNDER A FAVORABLE WRLY WIND FLOW. FRI NIGHT...MODELS ARE IN PRETTY GOOD AGREEMENT THAT A REINFORCING SECOND COLD FRONT WILL DROP THRU THE AREA BRINGING COLDER AIR MORE FIRMLY INTO THE UPPER LAKES...WITH 850MB TEMPS DROPPING TO -2 TO -4C BY 12Z SAT. IN CONCERT WITH FAIRLY STRONG DEEP LAYER QVECTOR CONVERGENCE THAT IS PROGGED TO SHIFT ACROSS THE AREA...LAKE ENHANCED SHOWERS WILL INCREASE. WETBULB ZERO HEIGHTS SUPPORT THE POTENTIAL FOR PCPN TO MIX WITH OR EVEN CHANGE TO SNOW OVER THE HIGH TERRAIN OF FAR W THE NEAR THE WI BORDER. OVER THE WEEKEND...DEEP...CHILLY AND MOIST CYCLONIC FLOW WILL DOMINATE AS MID/UPPER LEVEL LOW SPINS OVER NRN ONTARIO. WITH 850MB TEMPS IN THE -3 TO -6C RANGE...EXPECT PLENTY OF CLOUDS AND LAKE EFFECT PCPN. SHORTWAVES ROTATING AROUND THE LOW WILL BRING PERIODS OF HEAVIER/MORE WIDESPREAD LAKE ENHANCED PCPN. PCPN ON SAT WILL BE MOST FAVORED IN AREAS AFFECTED BY NW FLOW LAKE EFFECT. BACKING WINDS ON SUN WILL SHIFT PCPN TO AREAS THAT ARE MOST AFFECTED BY WESTERLY FLOW LAKE EFFECT. RAIN WILL MIX WITH OR CHANGE TO SNOW AT TIMES OVER THE HIGHER TERRAIN...ESPECIALLY DURING THE NIGHT AND MORNING HRS. WITH A LENGTHY PERIOD OF STRONG NW TO W WINDS ON LAKE SUPERIOR... INCLUDING GALES FOR A TIME...AND HIGH LAKE LEVELS (LAKE SUPERIOR IS CURRENTLY ABOUT 6 INCHES BLO THE RECORD HIGH FOR THIS TIME OF YEAR)...BEACH EROSION/FLOODING MAY BECOME A PROBLEM FOR AREAS THAT ARE EXPOSED TO WAVES GENERATED BY W TO NW WINDS. AS MENTIONED AT THE BEGINNING OF THIS DISCUSSION THERE IS MUCH BETTER AGREEMENT ON TRANSITIONING FLOW DURING THE MIDDLE AND END OF NEXT WEEK. AGREEMENT IS GOOD THAT THE MID LEVEL LOW WILL LINGER OVER NRN ONTARIO THRU AT LEAST MON...WHICH WILL KEEP THE UPPER LAKES UNDER ITS UNSETTLED INFLUENCE. LOW WILL BEGIN TO LIFT OUT TUE... LEADING TO A TRANSITION TO DRY WEATHER AND SOME TEMP MODERATION. MODERATION/DRY WEATHER WILL CONTINUE WED WITH A MORE ZONALLY ORIENTED FLOW TAKING SHAPE ACROSS THE NRN CONUS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 141 PM EDT THU OCT 2 2014 AS NEXT SYSTEM APPROACHES THIS EVENING...CONDITIONS WILL RAPIDLY DETERIORATE TO IFR/LIFR WITH UPSLOPE RAIN AND FOG. UTILIZED A NEARLY EVEN BLEND OF CONSENSUS SHORT TERM GUIDANCE AND THE HRRR OVER THE NEXT FEW HOURS...THEN CONSENSUS GUIDANCE WEIGHTED MORE HEAVILY TOWARD THE HIGH-RES WRF AND NAM TONIGHT INTO FRIDAY. EXPECT WORST CONDITIONS TONIGHT...FOLLOWED BY SLOW IMPROVEMENT FRI MORNING AS THE LOW AND ASSOCIATED LOW LEVEL MOISTURE MOVES NE OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 444 AM EDT THU OCT 2 2014 EXPECT DIMINISHING S WINDS THIS MORNING OVER THE EAST. WINDS WILL REMAIN LIGHT THROUGH MOST OF TONIGHT AS SFC LOW TO THE NORTH ACROSS LK SUPERIOR. ONCE THE LOW LIFTS TO THE NORTH OF LK SUPERIOR ON FRIDAY...STRONG WEST WINDS WILL SPREAD ACROSS LK SUPERIOR DUE TO TIGHT PRESSURE GRADIENT AND THE ARRIVAL OF COLDER AIR. GALE FORCE WINDS EXPECTED LATER FRIDAY AFTN...AND THESE WILL INCREASE TO 35-40 KTS FRIDAY NIGHT INTO SATURDAY AS WINDS SHIFT TO THE NORTHWEST AS COLDER AIR MOVES ACROSS LK SUPERIOR. GALE WATCH IN EFFECT FOR ALL BUT FAR WESTERN LK SUPERIOR FRIDAY AFTERNOON THROUGH EARLY SATURDAY AFTERNOON. AS IT STANDS NOW...GALE WARNINGS WILL EVENTUALLY BE ISSUED EITHER LATER TODAY OR TONIGHT. THOUGH GALES SHOULD DIMINISH ON SATURDAY AFTERNOON...WEST WINDS 20-30 KTS WILL PERSIST INTO SUNDAY AND SUNDAY NIGHT WITH GUSTY SOUTHWEST WINDS EXPECTED MONDAY INTO TUESDAY OUT AHEAD OF ANOTHER LOW PRESSURE SYSTEM DROPPING IN FROM SCNTRL CANADA. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY AFTERNOON FOR LSZ263>267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLA LONG TERM...ROLFSON AVIATION...TITUS MARINE...JLA
AREA FORECAST DISCUSSION
NWS KANSAS CITY/PLEASANT HILL MO
248 PM CDT Thu Oct 2 2014 .SHORT TERM...(This Evening through Friday Afternoon) Issued at 248 PM CDT THU OCT 2 2014 The ongoing thunderstorms will continue this afternoon and early evening ahead of a deep layer trough and an approaching cold front. As of 19Z the cold front was just entering the northwest portion of the CWA and slowly advancing eastward. The severe threat, hail and wind, is very limited for our CWA and located across our far southern counties along and south of a warm front. The front has made very little northward progress due to reinforced cool air from the morning/early afternoon convection to its north and thus it is not expected to move much this afternoon. By later this evening the warm sector will be shunted east with the passage of the aforementioned cold front with much of the deeper convection east of the CWA. There will be a low chance for post-frontal showers and isolated elevated thunderstorms overnight tonight, but that activity should not amount to much...per the HRRR and current 88D trends. Near sunrise tomorrow a secondary cold front quickly moves in and through the CWA behind the departing upper level trough. It will be rather breezy behind the front with northwest winds gusting to as high as 30 MPH advecting much cooler and drier air. There will also be a low chance pops for widely scattered showers...very hit or miss...and diurnally driven. .LONG TERM...(Friday Evening through Thursday) Issued at 248 PM CDT THU OCT 2 2014 Any clouds lingering into Friday evening over central Missouri will be fast to scatter out leaving clear skies overnight. This will set the stage for one of the coldest nights of the season so far with temperatures in the mid to upper 30s across much of the area. Some guidance is bringing parts of northern Missouri down below freezing, but this seems too cold since west winds should remain around 5 to 10 mph overnight. Coldest temperatures should be west of us, closer to the low-level ridge axis. Could still see some patchy frost across eastern KS into northern Missouri early Saturday morning particularly in areas sheltered from a westerly wind. This ridge axis will pass overhead on Saturday keeping temperatures seasonably chilly with highs in the 50s. Southerly winds on the back side of this feature will prevent Saturday night`s temperatures from getting much below 40 degrees while Sunday sees a nice warm up into the upper 60s and lower 70s. On Monday a very weak wave will rotate into the area on the back side of a large Great Lakes upper trough. Could see a few showers from this feature but overall precipitation chances are only 30 percent or so. Once this passes through, slow height rises will build into the Plains and allow temperatures to warm into the middle and upper 70s by Weds and Thurs. && .AVIATION...(For the 18Z TAFS through 18Z Friday Afternoon) Issued at 1217 PM CDT THU OCT 2 2014 There will be several more rounds of TSRA this afternoon that will briefly lower VIS as they pass over the terminals. CIS should remain IFR to perhaps low MVFR before a cold front moves through over the next few hours. Behind the front current CIGS are IFR so I maintain that into the evening before slow improvement tonight. Another cold front arrives near sunrise tomorrow that will create breezy northwest winds and a SCT-BKN cloud deck through much of the day. && .EAX WATCHES/WARNINGS/ADVISORIES... KS...FLASH FLOOD WATCH until 7 PM CDT this evening FOR KSZ057-060. MO...FLASH FLOOD WATCH until 7 PM CDT this evening FOR MOZ033-040- 043>046-053-054. && $$ SHORT TERM...Pietrycha LONG TERM...Hawblitzel AVIATION...Pietrycha
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1215 PM CDT THU OCT 2 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 SEVERAL TIMING ISSUES WILL BE THE MAIN CONCERN IN THE SHORT TERM. INITIAL FOCUS WILL BE BAND OF SHOWERS AND STORMS STARTING TO SPREAD INTO THE AREA AT 07Z FROM CENTRAL NEBRASKA. MODELS CONTINUE TO SUGGEST A STEADY PROGRESS OF THIS SYSTEM ACROSS THE CWA TODAY IN ADVANCE OF THE UPPER TROUGH. LATEST RAP HAS THE MAJORITY OF THE PRECIP EAST OF THE AREA BY 00Z. ALSO MAY NEED A MENTION OF FOG FOR A SHORT TIME THIS MORNING IN WEST CENTRAL IOWA BETWEEN HARLAN AND RED OAK WHERE VSBY IS REPORTED NEAR ZERO. WILL MONITOR UNTIL ISSUANCE FOR ANY CHANGE AS CLOUD COVER BEGINS TO SPREAD INTO THAT AREA. A NEW FEATURE THAT HAS SHOWN UP IN TONIGHTS MODELS IS A SECONDARY BAND OF SHOWERS BEHIND THE PRIMARY COLD FRONT ASSOCIATED WITH ANOTHER SHORT WAVE AS IT MOVES INTO NEBRASKA TONIGHT. AT THIS POINT HAVE KEPT POPS ON THE LOW SIDE AND MAINLY FOR WESTERN AND SOUTHERN PARTS OF THE AREA AS INDICATED BY 00Z MODELS. OTHERWISE WEATHER TURNS WINDY AND COLD BEHIND THE FRONT TONIGHT INTO FRIDAY WITH GOOD POTENTIAL FOR FROST OR FREEZE ACROSS MOST OF THE AREA SATURDAY MORNING. AT THIS TIME WILL CONTINUE MENTION OF THIS POTENTIAL IN THE HWO AND WAIT UNTIL LATER FORECAST FOR HEADLINES. .LONG TERM...(SATURDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 250 AM CDT THU OCT 2 2014 GENERALLY DRY AND WARMER IN THE EXTENDED PERIOD UNTIL TOWARDS THE END OF THE TIME FRAME WHEN ANOTHER FRONTAL SYSTEM WITH UPPER LEVEL SUPPORT DEVELOPS OVER THE REGION. POPS ON THE LOW SIDE FOR NOW DUE TO UNCERTAINTY IN POSITION AND TIMING. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1202 PM CDT THU OCT 2 2014 SCATTERED SHOWERS COULD IMPACT KLNK/KOMA TAF SITES FOR A FEW HOURS TO BEGIN TAF PERIOD...BUT GENERALLY PRECIP WAS WINDING DOWN ACROSS ERN NEBR. HOWEVER...CIGS GENERALLY BETWEEN FL010-020 WILL LINGER THIS AFTN BEFORE DRIER AIR MOVES IN LATER. ANOTHER DISTURBANCE WILL DROP SE ACROSS THE STATE LATE TONIGHT USHERING IN A REINFORCING COLD FRONT THAT WILL BOOST WINDS AND COULD ALSO BRING SCATTERED SHOWERS. AT THIS TIME CHANCES APPEARED A LITTLE HIGHER FROM KOFK TO KLNK WHERE MENTION WAS INCLUDED IN THE 18Z TAF. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ SHORT TERM...FOBERT LONG TERM...FOBERT AVIATION...CHERMOK
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
316 PM EDT THU OCT 2 2014 .SYNOPSIS... HIGH PRESSURE RIDGING SOUTH ACROSS THE AREA WILL MOVE OFFSHORE TONIGHT INTO FRIDAY MORNING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY MORNING. DRY AND COOL HIGH PRESSURE WILL FOLLOW FOR THE WEEKEND AND PERSIST INTO EARLY NEXT WEEK. A WARMING TREND IS EXPECTED FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM THURSDAY...EARLY IN THE PERIOD HIGH PRESSURE WILL BE CENTERED UP AND DOWN MUCH OF THE COASTLINE. WIND HAS SOME VARIABILITY TO IT BUT IS MAINLY LIGHT NE. COASTAL LOCATIONS HAVE TURNED MORE ONSHORE DUE TO SEABREEZE AND AREAS NOT TOO FAR SOUTH ALSO VEERING DUE TO SYNOPTIC FLOW CHANGE. THE MARINE LAYER HAS LEAD TO A SPRINKLE OR TWO WITHIN THE AREA OF MORE ENHANCED CU BUT NEGATIVE VORTICITY ADVECTION SHOULD SOON TEAM UP WITH WEAKENING LOW LEVEL LAPSE RATES TO MAKE THOSE A THING OF THE PAST. LATER ON THE REST OF THE REGION WILL GET IN ON THE AFOREMENTIONED SYNOPTIC SCALE VEERING OF THE FLOW AS THE AXIS OF THE SURFACE RIDGE PROGRESSES OFF THE COAST. THIS SHOULD HELP LEAD TO SOME DEEPER LOW LEVEL MOISTURE WHEN COMPARED TO RECENT NIGHTS. THE SAME HOLDS TRUE ALONG THE COAST COMPLIMENTS OF THE SEA BREEZE. INTERESTINGLY GUIDANCE IS NOT MUCH MORE IN FAVOR OF FOG WHEN COMPARED TO RECENT NIGHTS. FOR NOW HAVE JUST ADVERTISED FOG AREA-WIDE MUCH LIKE WE DID LAST NIGHT. HAVE DEFERRED TO THE EVENING SHIFT TO DETERMINE WHERE IT MAY BECOME LOCALLY DENSE, IF ANYWHERE. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 PM THURSDAY...FRIDAY WILL BE THE LAST DAY OF THE REMNANT SUBTROPICAL WARM AND HUMID AIRMASS. A WEAK BUBBLE OF HIGH PRESSURE OFF THE COAST WILL DISAPPEAR FROM THE WEATHER MAP BY FRIDAY AFTERNOON...AS DEEP MOISTURE INCREASES ACROSS THE WESTERN AND CENTRAL CAROLINAS AHEAD OF A STRONG COLD FRONT. IN THE UPPER LEVELS A VORT MAX WILL LIFT NORTHWARD INTO THE SOUTHERN GREAT LAKES AHEAD OF THE MAIN UPPER TROUGH STILL BACK ACROSS THE CENTRAL PLAINS. MORNING SUNSHINE FRIDAY AND 850 MB TEMPS OF +14C TO +16C BOTH MEAN TEMPERATURES SHOULD ROCKET INTO THE LOWER TO MIDDLE 80S BY EARLY AFTERNOON. THICKENING MID AND HIGH CLOUDS OVERSPREADING THE EASTERN CAROLINAS DURING THE AFTERNOON MAY BRING RAIN AND EMBEDDED T-STORMS BY LATE IN THE DAY ACROSS THE SC PEE DEE REGION...SPREADING EASTWARD TO THE COAST DURING THE EVENING HOURS. FORECAST INSTABILITY AND SHEAR PROFILES LOOK INSUFFICIENT TO GENERATE A SIGNIFICANT SEVERE WEATHER THREAT...AND MY FORECAST RAINFALL AMOUNTS ARE ONLY 0.2 TO 0.3 INCHES. THE PERIOD FOR THE BEST PRECIPITATION POTENTIAL APPEARS TO BE BETWEEN 00-06Z SATURDAY...COINCIDENT WITH THE BEST 300 MB DIFFLUENCE WHICH WILL SUPPORT THE RAIN AND EMBEDDED CONVECTION. AS OFTEN OCCURS LOCALLY THE FRONT WILL NOT COME THROUGH CLEANLY IN ONE PIECE. THE SHIFT TO WESTERLY WINDS AND SOME DRIER LOW-LEVEL AIR WILL ARRIVE AROUND SUNRISE SATURDAY MORNING. THE SIGNIFICANT COLD ADVECTION WILL BE DELAYED UNTIL SATURDAY EVENING WHEN LOW- LEVEL WINDS FINALLY TURN NORTHWESTERLY AND 850 MB TEMPS START TO FALL IN EARNEST...REACHING +3C TO +5C BY 12Z SUNDAY. WITH THIS DELAYED COLD AIR ADVECTION I HAVE TRENDED FORECAST LOWS FRIDAY NIGHT ABOVE MOS GUIDANCE BY SEVERAL DEGREES...BETTER MATCHING THE 12Z NAM/GFS MODEL CONSENSUS. MOS GUIDANCE APPEARS REASONABLE DURING THE DAY SATURDAY WITH HIGHS IN THE UPPER 70S INLAND AND LOWER 80S ON THE COAST...AND WITH LOWS SATURDAY NIGHT AROUND 50 ON THE COAST AND DIPPING INTO THE 40S INLAND. LOCATION FORECAST LOW SAT NIGHT LAST TIME IT WAS THIS COLD WILMINGTON 50 MAY 20 FLORENCE 45 APRIL 17 N. MYRTLE BEACH 50 MAY 20 LUMBERTON 44 APRIL 24 && .LONG TERM /SUNDAY THROUGH THURSDAY/... AS OF 300 PM THURSDAY...MID LEVEL TROUGHING SUN WILL TRANSITION TO WEAK 5H RIDGING BY THE END OF THE PERIOD. EARLY NEXT WEEK THERE IS A DEGREE OF UNCERTAINTY PRESENT IN THE FORECAST. RECENT MEDIUM RANGE SOLUTIONS SHOW AMPLIFICATION OF MID LEVEL TROUGH OVER THE LOWER MS VALLEY WITH SOME SOLUTIONS SHOWING A CUTOFF DEVELOPING. EITHER SOLUTION LEADS TO SURFACE WAVE DEVELOPMENT...IN VARYING STRENGTHS...OVER THE SOUTHERN CONUS ALONG A FRONT EXTENDING SOUTH FROM CANADA. THIS COULD LEAD TO A PERIOD OF UNSETTLED WEATHER TUE NIGHT INTO WEDNESDAY AS THE FRONT AND SURFACE WAVE CROSS THE CAROLINAS. SOUTHWEST FLOW AHEAD OF THE FRONT WILL PUMP DEEPER MOISTURE INTO THE REGION AND WEAK CONVERGENCE/LIFT WITH THE FRONT AND SOME WEAK MID LEVEL SUPPORT DOES SUGGEST THE POSSIBILITY OF SOME PRECIP LATE TUE AND TUE NIGHT. WILL GO AHEAD AND INTRODUCE SLIGHT CHC POP AT THIS TIME GIVEN THAT CONFIDENCE IS ON THE LOW SIDE. TEMPERATURES START OUT BELOW CLIMO WITH POTENTIAL FOR GOOD RADIATIONAL COOLING SUN NIGHT SETTING UP WHAT COULD BE THE COLDEST MORNING OF THE EARLY FALL SEASON. TEMPS RETURN BACK TO CLIMO MON AND HANG NEAR TO SLIGHTLY ABOVE CLIMO THROUGH THE END OF THE PERIOD. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... AS OF 18Z...THE HRRR MODEL IS DEPICTING LIGHT SHOWERS ALONG THE RESULTANT THIS AFTERNOON. JUST LOOKED AT THE CU OUTSIDE...AND IT LOOKS PRETTY GOOD SO WILL ADD VCSH TO THE COASTAL TAFS. LIGHT WINDS TONIGHT WITH FOG AGAIN DEVELOPING WITH CONTINUED LIGHT WINDS AT THE BOUNDARY LAYER. FOG WILL MOST DENSE AT LBT. FRIDAY...A WARM DAY WITH SOUTHWEST FLOW DEVELOPING. INCREASING CLOUDS IN ADVANCE OF A RATHER STRONG COLD FRONT. ANY CONVECTION WILL LIKELY OCCUR WELL AFTER THE END OF THE FORECAST PERIOD. EXTENDED OUTLOOK...SHOWERS AND A CHANCE OF TSTMS/MVFR LATE FRI/EARLY SAT WITH A COLD FRONT. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM THURSDAY...EARLY ON THERE WILL STILL BE A LIGHT NORTH AND EASTERLY COMPONENT TO THE FLOW WITH RIDGE AXIS RIGHT OVER THE REGION. AS THE NIGHT PROGRESSES THIS RIDGE AXIS WILL MOVE OFFSHORE AND THE FLOW WILL GENTLY VEER TO SOUTHEAST OR EVEN SOUTH. WITH SUCH A LIGHT GRADIENT THE WIND SPEED SHALL REMAIN CAPPED AT 10KT OR LESS THROUGH THE PERIOD AND WIND CHANGE. WITH THE ONLY SWELL-PRODUCING SYSTEM SEVERAL HUNDRED MILES EAST OF NANTUCKET AND MOST OF THIS ENERGY SHOULD BE INTERCEPTED BY CAPE HATTERAS. WNA SPECTRAL BULLETINS DO HINT AT SOME 2 FT 7 SECOND ENERGY EITHER BYPASSING OR REFRACTING AROUND HATTERAS ALONG THE OUTER FRINGES OF THE 20NM ZONES. OTHERWISE THE MAIN WAVE WILL BE JUST THE WIND-GENERATED SEAS WHICH WILL OBVIOUSLY BE MINIMAL. THE COMBINATION OF THE TWO WILL STILL ONLY CALL FOR A FORECAST OF JUST 2 FT AREA-WIDE. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 300 PM THURSDAY...A WEAK BUBBLE OF HIGH PRESSURE JUST OFF THE CAROLINA COAST WILL BE QUICKLY DISPLACED FRIDAY AFTERNOON AS A STRONG COLD FRONT ZIPS EASTWARD ACROSS THE MID-SOUTH. THIS FRONT IS THE FIRST REALLY SIGNIFICANT ONE OF THE FALL SEASON AND SHOULD REACH THE BEACHES OF NORTH AND SOUTH CAROLINA EARLY SATURDAY MORNING. AHEAD OF THE FRONT SOUTHWEST WINDS WILL INCREASE TO 10-15 KNOTS FRIDAY AFTERNOON...TO 15-20 KNOTS FRIDAY NIGHT...THEN WILL SHIFT WESTERLY AROUND 15 KNOTS DURING THE DAY SATURDAY. IT WILL PROBABLY TAKE UNTIL SATURDAY EVENING FOR THE COLD AIR TO BEGIN BLEEDING SOUTH INTO THE REGION AS WINDS FINALLY TURN MORE NORTHWESTERLY AND INCREASE TO 15-20 KT. SEAS INITIALLY ONLY 2 FEET FRIDAY WILL GRADUALLY BUILD TO 3-5 FT FRIDAY NIGHT...BUT SHOULD BUILD NO HIGHER AS WIND DIRECTIONS VEER MORE OFFSHORE SATURDAY AND SATURDAY NIGHT...LIMITING THE EFFECTIVE FETCH LENGTH. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 300 PM THURSDAY...SOLID 15 KT NORTHWEST FLOW AT THE START OF THE PERIOD WILL DECREASE DURING THE DAY. SURFACE RIDGE AXIS MOVES OVERHEAD LATE SUN WITH WINDS BACKING TO WEST-SOUTHWEST SUN NIGHT AND MON. WEAK SURFACE HIGH LINGERS OFF THE COAST INTO TUE...MAINTAINING LIGHT SOUTHERLY FLOW THROUGH THE END OF THE PERIOD. SEAS WILL RUN 2 FT OR LESS THROUGH THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...TRA NEAR TERM...MBB SHORT TERM...TRA LONG TERM...III AVIATION...MBB/DL
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
120 PM EDT THU OCT 2 2014 .SYNOPSIS... HIGH PRESSURE RIDGING SOUTH ACROSS THE AREA WILL MOVE OFFSHORE TONIGHT INTO FRIDAY MORNING. A STRONG COLD FRONT WILL MOVE ACROSS THE AREA SATURDAY MORNING. DRY AND COOL HIGH PRESSURE WILL FOLLOW FOR THE WEEKEND AND PERSIST INTO EARLY NEXT WEEK. A WARMING TREND IS EXPECTED FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 120 PM UPDATE...JUST A QUICK UPDATE TO INCREASE CLOUD COVER AND ADD SPRINKLES ALONG THE COAST OF MAINLY NC. A NORTHEASTERLY RESULTANT SEA BREEZE HAS IMPORTED SOME LOW LEVEL MARINE AIR CONTAINING HIGHER LOW LEVEL MOISTURE INTO THE CAPE FEAR REGION. THIS AIR IS THEN BEING LIFTED BY A WELL-DEFINED VORT MAX STREAKING RIGHT OVERHEAD AT THE CURRENT TIME. THE CONTINUED DRY MID LEVELS WILL PRECLUDE MEASURABLE RAINFALL ANYWHERE. ADDITIONALLY...THE ADDED CLOUD COVER AND ISOLATED SPRINKLES WILL LIKELY ONLY BE AROUND FOR THE NEXT 1-3 HOURS...AFTER WHICH TIME THE MOISTURE MAY LINGER BUT THE LARGE SCALE ASCENT WILL CEASE AS THE SENSE OF VORTICITY ADVECTION CHANGES TO NEGATIVE. AS OF 1000 AM THURSDAY...12Z RAOBS FROM BOTH MHX AND CHS SHOW A SMALL INCREASE IN PRECIPITABLE WATER VALUES MOSTLY MANIFESTED IN THE LOW LEVELS. A FEW FAIR WEATHER CUMULUS CLOUDS MAY DEVELOP IN THE HEATING OF THE AFTERNOON...ANYWHERE UNDERNEATH THE MAIN SUBSIDENCE INVERSION AT 7KFT BEING FAIR GAME FOR A CLOUD BASE. ON AVERAGE TEMPERATURES ARE 2-3 DEGREES WARMER THAN AT THIS TIME YESTERDAY. THIS IS CURRENTLY REFLECTED IN THE CURRENT FORECAST OF HIGH TEMPERATURES. NO CHANGES ARE ANTICIPATED. && .SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY...THE COLD FRONT ASSOCIATED WITH A MAJOR PATTERN CHANGE REMAINS ON TRACK TO MOVE ACROSS THE AREA LATE FRIDAY/EARLY SATURDAY. I HAVE INCREASED POPS SLIGHTLY TO ADDRESS INCREASING CONFIDENCE. FOR SATURDAY...GUIDANCE HAS WARMED DRAMATICALLY AS THE COLD AIR ADVECTION IS DELAYED EVEN FURTHER WARRANTING A MARKED INCREASE IN HIGHS FOR SATURDAY...NOW APPROACHING 80 FOR MOST AREAS. MUCH COOLER SUNDAY WITH LOWS IN THE 40S FOR MOST AREAS AND HIGHS NOT ECLIPSING THE 70 DEGREE MARK. MONDAY MORNING LOOKS TO BE THE COOLEST VIA IDEAL RADIATIONAL CONDITIONS WITH 40S CWA WIDE. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... AS OF 3 AM THURSDAY...THE NORTHWEST FLOW WILL CONTINUE SUNDAY ON THE ORDER OF 10-15 KNOTS. LATE IN THE DAY THE FLOW WILL SHIFT TO THE SOUTHWEST AS HIGH PRESSURE REALIGNS OFF THE CAROLINA COAST. THIS FLOW WILL CONTINUE THROUGH THE DAY MONDAY. WIND SPEEDS DROP DOWN TO AROUND TEN KNOTS. SIGNIFICANT SEAS WILL BE 1-3 FEET. && .AVIATION /18Z THURSDAY THROUGH WEDNESDAY/... AS OF 18Z...THE HRRR MODEL IS DEPICTING LIGHT SHOWERS ALONG THE RESULTANT THIS AFTERNOON. JUST LOOKED AT THE CU OUTSIDE...AND IT LOOKS PRETTY GOOD SO WILL ADD VCSH TO THE COASTAL TAFS. LIGHT WINDS TONIGHT WITH FOG AGAIN DEVELOPING WITH CONTINUED LIGHT WINDS AT THE BOUNDARY LAYER. FOG WILL MOST DENSE AT LBT. FRIDAY...A WARM DAY WITH SOUTHWEST FLOW DEVELOPING. INCREASING CLOUDS IN ADVANCE OF A RATHER STRONG COLD FRONT. ANY CONVECTION WILL LIKELY OCCUR WELL AFTER THE END OF THE FORECAST PERIOD. EXTENDED OUTLOOK...SHOWERS AND A CHANCE OF TSTMS/MVFR LATE FRI/EARLY SAT WITH A COLD FRONT. OTHERWISE VFR. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 1000 AM THURSDAY...JUST ABOUT AS QUIET AS IT GETS OVER THE WATER. HIGH PRESSURE COVERING NOT ONLY THE LANDMASS BUT ALSO THE FIRST FEW HUNDRED MILES OF OCEAN MAKING FOR A VERY LIGHT ONSHORE FLOW. NO REAL SWELL ENERGY TO SPEAK OF SO THE PALTRY WIND WAVE THE PREDOMINANT SEA STATE. LOOKS LIKE SEAS CAPPED AT 2 FT. SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/... AS OF 3 AM THURSDAY...SOUTHERLY WINDS WILL QUICKLY PICK UP IN INTENSITY THROUGH THE DAY FRIDAY WITH A 15-20 KNOT RANGE BY DAYS END. THE FLOW WILL VEER SLIGHTLY TO SOUTHWEST FRIDAY NIGHT AND INCREASE BY A COUPLE OF KNOTS BEFORE THE COLD FRONT MOVES ACROSS SATURDAY MORNING. IT APPEARS WINDS AND SEAS WILL STAY JUST BELOW SMALL CRAFT CRITERIA. SATURDAY WILL SEE WINDS SUBSIDE AND TURN TO THE NORTHWEST. SEAS DIMINISH FROM 3-5 FEET LATE FRIDAY INTO EARLY SATURDAY TO 2-4 FEET BY LATE SATURDAY. LONG TERM /SUNDAY THROUGH MONDAY/... AS OF 3 AM THURSDAY...THE EXTENDED PERIOD WILL BE VERY TRANQUIL AS THE DEEP CYCLONIC FLOW PREVAILS BASICALLY THROUGH THE PERIOD. HIGH PRESSURE MOVING FROM THE SOUTHWEST TO OFF THE EAST COAST WILL BE THE MAIN SURFACE FEATURE. THERE IS A DECENT SHORTWAVE RIDING DOWN IN THE MAIN FLOW THAT MAY PROVIDE SOME SHOWERS ACROSS THE TENNESSEE VALLEY BUT THE LIMITED MOISTURE SHOULD NOT MAKE IT TO THE COASTAL PLAINS. TEMPERATURES WILL START OUT THE PERIOD WITH HIGHS IN THE 70S AND LOWS IN THE 50S. BY WEDNESDAY EXPECT LOWER 80S FOR HIGHS WITH 60S FOR LOWS ALONG THE COAST WITH 50S INLAND. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...MBB SHORT TERM...SHK LONG TERM...SHK AVIATION...43
AREA FORECAST DISCUSSION
NWS CLEVELAND OH
640 PM EDT THU OCT 2 2014 .SYNOPSIS... A STRONG COLD FRONT OVER THE MISSISSIPPI VALLEY WILL CROSS THE AREA FRIDAY AFTERNOON AND EVENING. A SURFACE TROUGH OF LOW PRESSURE ASSOCIATED WITH A TROUGH ALOFT WILL MOVE ACROSS THE LOWER GREAT LAKES SATURDAY. HIGH PRESSURE WILL BEGIN TO BUILD INTO THE OHIO VALLEY ON SUNDAY AND THEN ANOTHER TROF WILL MOVE THROUGH ON MONDAY. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... AMPLE MOISTURE UPSTREAM SHOULD LEND ITSELF TO A PARTLY CLOUDY SKY TONIGHT...ESPECIALLY IN THE WESTERN THIRD OF THE FORECAST AREA. THE LATEST RAP AND NAM RUNS INDICATE CLEARING ACROSS THE ENTIRE FORECAST AREA THROUGH THE FIRST PART OF TONIGHT...BUT THE CURRENT SATELLITE PRESENTATION CONTINUES TO SUGGEST OTHERWISE WITH MID LEVEL MOISTURE CONTINUING TO STREAM ACROSS THE FORECAST AREA. SO THE SKY FORECAST LENDS ITSELF TO PERSISTENCE RATHER THAN MODEL OUTPUT...AT LEAST THROUGH TONIGHT. SOME SHOWER ACTIVITY IS EXPECTED TONIGHT AS WELL. HOWEVER...THE HIGHER POPS WILL BE IN THE FAR WESTERN PART OF THE FORECAST AREA...THEN DECREASE EASTWARD. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SUNDAY NIGHT/... THE PROBLEM IS HOW QUICKLY WILL THE SHOWERS AND THUNDERSTORMS SPREAD EAST AND WILL THE THUNDERSTORMS BE WIDESPREAD OR JUST A CHANCE. WILL SPREAD THE SHOWERS AND SCATTERED THUNDERSTORMS SOMEWHAT QUICKLY EAST ON FRIDAY. THE LATEST MODEL RUNS ARE A LITTLE QUICKER. AT THIS TIME STILL KEPT THE THUNDERSTORMS TO A CHANCE. WE WILL HAVE PLENTY OF SHEAR AND THE WINDS ALOFT WILL BE STRONG ENOUGH IF THE AIRMASS BECAME UNSTABLE WE COULD HAVE SOME ISOLATED STRONG TO SEVERE THUNDERSTORMS AND EVEN AN ISOLATED TORNADO. THIS THREAT WILL HAVE TO BE MONITORED. THE THUNDERSTORM THREAT WILL END QUICKLY AFTER THE FRONTAL PASSAGE. THERE COULD BE A LITTLE LULL IN THE SHOWER ACTIVITY IN THE EVENING ESPECIALLY WEST OF CLE AND AKRON. AN UPPER LOW WILL BE MOVING ACROSS THE NORTHERN PORTION OF THE AREA FRIDAY NIGHT...AND THAT WILL MEAN SHOWERS LIKELY. ON SATURDAY A THREAT OF SHOWERS WILL CONTINUE AS AN UPPER TROF MOVES THROUGH. A THREAT OF SHOWERS WILL CONTINUE THROUGH SATURDAY NIGHT THROUGH SUNDAY NIGHT ESPECIALLY IN THE NORTH AS TROFS MOVE THROUGH. WENT CLOSE TO GUIDANCE TEMPERATURES. && .LONG TERM /MONDAY THROUGH THURSDAY/... A THREAT OF SHOWERS WILL CONTINUE MONDAY INTO TUESDAY WITH THE UPPER TROF IN THE AREA. STARTING WEDNESDAY THE UPPER LOW BEGINS TO PULL AWAY LEAVING THE FLOW ACROSS THE REGION MORE ZONAL...THAT IS ACCORDING TO THE GFS AND GFSENS. THE ECMWF IS MUCH SLOWER WITH THIS TRANSITION AND BRINGS ANOTHER SIGNIFICANT PIECE OF ENERGY THROUGH THE TROUGH AND MAKING FOR ANOTHER CLOSED LOW ACROSS THE OHIO VALLEY FOR WEDNESDAY. WILL TAKE NOTE OF THIS...BUT CONTINUE THE FORECAST IN THE GENERAL DIRECTION OF THE TROUGH SLOWLY PULLING OUT. THAT WILL LEAVE A CHANCE FOR SHOWERS IN THE FORECAST FOR TUESDAY AND WEDNESDAY AND FOR NOW KEEPING THURSDAY DRY. LOWS WILL STICK IN THE 40S. HIGH TEMPERATURES WILL SLOWLY MODERATE AND BY THURSDAY RETURN CLOSER TO NORMALS...WHICH THIS TIME OF YEAR ARE IN THE UPPER 60S. && .AVIATION /18Z THURSDAY THROUGH TUESDAY/... VFR CONDITIONS THROUGH THE OVERNIGHT. SOUTHERLY FLOW WILL CONTINUE AND BEGIN TO INCREASE EVEN BEFORE MORNING FOR MFD/CLE/ERI. LOW LEVEL WIND SHEAR A CONCERN PRE-DAWN FOR TOL/FDY. COLD FRONT APPROACHES FOR THE DAYTIME HOURS ON FRIDAY. SHOWERS CERTAIN AND THUNDER A GOOD POSSIBILITY FROM LATE MORNING ONWARD. FRONTAL PASSAGE NOT UNTIL AFTER 18Z. .OUTLOOK...NON VFR FRIDAY AFTERNOON IN SHOWERS AND THUNDERSTORMS. NON VFR LIKELY SATURDAY NE OH/NW PA...PERHAPS LINGERING INTO SUNDAY MORNING. && .MARINE... THE GRADIENT WILL BEGIN TO TIGHTEN AND WINDS WILL BEGIN TO PICK UP TONIGHT FROM THE SOUTH AS A STRONG COLD FRONT APPROACHES FROM THE WEST. SMALL CRAFT ADVISORIES MAY START AS EARLY AS THE MORNING FOR THE WESTERN BASIN WITH WINDS GETTING NEAR THE 20-25 KNOT MINIMUM. SOME THUNDERSTORMS POSSIBLE WITH THE FRONT THAT WILL PASS DURING THE DAYTIME HOURS FRIDAY. IN THE WAKE OF THE FRONT WINDS AND CONDITIONS ON THE LAKE WILL DETERIORATE AND REMAIN THAT WAY FOR SEVERAL DAYS. A GOOD PUSH OF COLD AIR WILL BRING WINDS UP FRIDAY NIGHT AND BY THEN A SMALL CRAFT ADVISORY IS A CERTAINTY. THE LOW GETS HUNG UP ACROSS CENTRAL ONTARIO/NORTHERN LAKES WHILE HIGH PRESSURE REMAINS ACROSS THE SOUTHEAST STATES. THE WSW GRADIENT WILL REMAIN RELATIVELY TIGHT AND A PERIOD OF 20-30 KNOTS WINDS CAN BE EXPECTED FROM FRIDAY NIGHT THROUGH THE WEEKEND. THE WINDS BECOME A LITTLE MORE UNCERTAIN INTO EARLY NEXT WEEK. THE LOW WILL STILL LINGER ACROSS THE GREAT LAKES. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...NONE. PA...NONE. MARINE...NONE. && $$ SYNOPSIS...KIELTYKA NEAR TERM...MAYERS SHORT TERM...KIELTYKA LONG TERM...OUDEMAN AVIATION...OUDEMAN MARINE...OUDEMAN
AREA FORECAST DISCUSSION
NWS TULSA OK
1219 PM CDT THU OCT 2 2014 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. TSRA POTENTIAL HIGH AT ALL TERMINALS THROUGH THE FIRST 6 TO 9 HOURS OF THE VALID TAF PERIOD...INCLUDING THE POTENTIAL FOR BOTH HAIL AND SHIFTING WINDS. WILL HANDLE ANY SEVERE POTENTIAL WITH AMENDMENTS WITH THE EXPECTED LINE OF TSRA NOT YET FORMED. COLD FRONT WILL PASS THROUGH THE AREA THIS AFTERNOON AND EVENING...WHICH WILL SHIFT WINDS FROM THE SOUTH TO THE WEST AND NORTHWEST. A SECONDARY COLD FRONT WILL PASS THROUGH MOST OF THE TERMINALS TOMORROW MORNING...BRINGING GUSTY NORTH WINDS. MVFR CIGS WILL BE POSSIBLE FOR A FEW HOURS FOLLOWING THE FIRST FRONT BEFORE THEY LIFT. && .PREV DISCUSSION... /ISSUED 1034 AM CDT THU OCT 2 2014/ ..UPDATE... DISCUSSION... MORNING STORMS HAVE BEHAVED ABOUT AS EXPECTED...WITH SPORADIC HAIL AND EVEN A DAMAGING WIND REPORT. EXCEPT IN A COUPLE OF STORMS...THE OVERALL INTENSITY TREND HAS BEEN DOWN SINCE SUNRISE. HRRR HANDLING THIS QUITE WELL. LEADING EDGE OF THE COLD FRONT JUST WEST OF THE FORECAST AREA AT THIS TIME...EXTENDING FROM SOUTH CENTRAL KANSAS TO ABOUT OKC AND INTO SOUTHWEST OKLAHOMA. PLENTY OF INSTABILITY CONTINUES AHEAD OF THE FRONT IN EASTERN OKLAHOMA AND WESTERN ARKANSAS...ESPECIALLY IN PARTS OF SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS THAT HAVE NOT SEEN ANY STORMS. DEEP LAYER SHEAR IS CURRENTLY RELATIVELY LOW ACROSS THE AREA...BUT WILL INCREASE THROUGH THE REST OF THE MORNING AND INTO THE AFTERNOON AS THE UPPER SYSTEM JUST EAST OF THE ROCKIES MOVES CLOSER. LARGELY UNIDIRECTIONAL SHEAR SHOULD LEAD TO A LINEAR STORM MODE...WITH DAMAGING WINDS AND LARGE HAIL THE MOST LIKELY THREATS. 0-3KM SHEAR VECTORS ARE PERPENDICULAR TO THE EXPECTED SQUALL LINE MOVEMENT...BUT THE MAGNITUDES ARE RELATIVELY WEAK...WHICH SHOULD LIMIT THE OVERALL POTENTIAL FOR LEADING EDGE TORNADOES. THE THREAT WILL DEFINITELY NOT BE ZERO THOUGH. THE MAIN LINE OF STORMS SHOULD CLEAR THE FORECAST AREA BY AN HOUR OR TWO AFTER SUNSET...IF NOT BY SUNSET IF THE HRRR TIMING VERIFIES. WITH THE MAJORITY OF THE FORECAST AREA EXPECTED TO SEE THE LINE OF STORMS BEFORE SUNSET...LOSS OF DAYTIME HEATING SHOULD NOT AFFECT THE LINES INTENSITY. HAVE INCREASED THE CONDITIONAL SEVERE PROBABILITIES THIS AFTERNOON AND EARLY EVENING ACROSS SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS TO ACCOUNT FOR THIS. PRODUCTS WILL CONTINUE TO BE UPDATED THROUGH THE LATE MORNING AND EARLY AFTERNOON TO KEEP UP WITH THE RADAR TRENDS. PREV DISCUSSION... /ISSUED 703 AM CDT THU OCT 2 2014/ DISCUSSION... THE 12Z TAF DISCUSSION IS INCLUDED BELOW... AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM. PRETTY COMPLICATED AVIATION FORECAST TODAY...WITH LOW CIGS AND TSRA TO CONTEND WITH. THE MORNING STORMS ARE LIKELY DONE AFFECT THE TAF SITES...SO THE FOCUS THEN TURNS TO THE AFTERNOON. USED THE LATEST HRRR DATA COMBINED WITH PREV FORECAST TO HONE IN ON THE SEVERAL HOUR WINDOW OF BEST OPPORTUNITY AT EACH TAF SITE. TSRA SHOULD CLEAR ALL OF THE TERMINALS BY ABOUT 03Z THIS EVENING. AS FOR THE LOW CLOUDS...THERE IS SOME MVFR STRATUS AT KFSM AND THIS COULD MOVE INTO KMLC LATER. THE RUC/NAM MOISTURE PROFILES SUGGEST LOW CLOUDS BY LATE IN THE DAY OR EARLY EVENING BEHIND THE FRONT INITIALLY...AND THEN GRADUALLY CLEAR THINGS OUT OVER EASTERN OK TOWARD THE END OF THIS FORECAST. LACY PREV DISCUSSION... /ISSUED 411 AM CDT THU OCT 2 2014/ DISCUSSION... ELEVATED THUNDERSTORMS CONTINUE TO EXPAND WITHIN STRENGTHENING LOW LEVEL JET AXIS THIS MORNING ACROSS CENTRAL AND PARTS OF EASTERN OKLAHOMA. EXPECT THIS TO CONTINUE SHIFTING EAST THROUGH THE MORNING WITH A THREAT OF MARGINAL WIND GUSTS AND HAIL BUT SEVERE PROBABILITY SHOULD REMAIN LOW WITH THE INITIAL ACTIVITY. APPEARS NOW THAT THIS SHOULD MOVE OFF FAST ENOUGH TO ALLOW FOR SIGNIFICANT DESTABILIZATION TO OCCUR OVER LARGE PORTION OF THE FORECAST AREA THIS AFTERNOON IN ADVANCE OF PACIFIC COLD FRONT THAT CURRENTLY LIES FROM TX PANHANDLE TO NE KANSAS. UPPER WAVE EJECTING ACROSS THE PLAINS DURING THE AFTERNOON WILL INCREASE SHEAR AS WELL...LEADING TO RELATIVELY WIDESPREAD SEVERE WEATHER EVENT LATER TODAY. SHEAR PROFILES WILL BE MAINLY UNIDIRECTIONAL AND FAVOR LINEAR STORM MODE...HOWEVER SOME INITIAL ALBEIT SHORT- LIVED SUPERCELL DEVELOPMENT SEEMS PROBABLE. THUS ALL MODES OF SEVERE ARE POSSIBLE ALONG WITH HEAVY RAINFALL AMOUNTS. FRONT AND UPPER TROUGH WILL SWEEP THROUGH THE AREA THIS EVENING WITH STORMS ENDING ACROSS WESTERN ARKANSAS BEFORE 06Z. DEEP LONGWAVE TROUGH DEVELOPING OVER GREAT LAKES REGION FRI/SAT WILL HELP BRING A SECOND STRONGER SURGE OF CANADIAN AIR INTO THE AREA FRIDAY WITH A PERIOD OF GUSTY NW WINDS AND MUCH COOLER TEMPS... ESPECIALLY BY SAT MORNING WHEN MANY AREAS WILL SEE UPPER 30S AND LOW 40S. NICE WEEKEND WILL FOLLOW WITH A STRONG WARM UP SUNDAY AFTERNOON AS LOW LEVEL WINDS QUICKLY RETURN FROM THE SOUTH. A WEAK BOUNDARY WILL SLIDE THROUGH MONDAY BUT MOISTURE WILL REMAIN VERY LIMITED AT THAT TIME AND HAVE KEPT THE FORECAST DRY. UPPER RIDGE BUILDS IN FROM THE SOUTHWEST BY MID WEEK WITH MUCH ABOVE NORMAL TEMPERATURES RETURNING BY WEDNESDAY...POSSIBLY CLOSE TO WHAT WE SAW THE LAST COUPLE OF DAYS. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...NONE. AR...NONE. && $$ SHORT TERM...22 LONG TERM....05 AVIATION...22
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
353 PM CDT THU OCT 2 2014 .DISCUSSION... CURRENTLY... SCATTERED SHOWERS AND THUNDERSTORMS DRIVEN BY WAA CONTINUE TO MOVE THROUGH THE MIDSOUTH. A COLD FRONT STRETCHES FROM NORTHERN MISSOURI TO SOUTH TEXAS AND WILL CONTINUE TO PROGRESS EASTWARD TOWARDS THE CENTRAL AND SOUTHERN MISSISSIPPI VALLEY. FLOW IS SOUTHERLY AHEAD OF THE FRONT...PULLING UP WARM... MOIST...UNSTABLE AIR INTO THE MIDSOUTH FROM THE GULF OF MEXICO. CLOUDS AND SHOWERS HAVE CREATED A BROAD RANGE OF TEMPERATURES THROUGH THE MIDSOUTH. AS OF 3PM...MEMPHIS WAS AT 90 DEGREES DUE TO A BREAK IN CLOUD COVER...WHEREAS OXFORD MISSISSIPPI WAS ONLY AT 73 DEGREES DUE TO A NEARBY THUNDERSTORM. DEWPOINTS ARE PEAKING IN THE LOW 70S AREA WIDE. STORMS HAVE ALREADY BEGAN TO DEVELOP ALONG THE FRONT FURTHER WEST IN NW AR...EASTERN OK AND SOUTHERN MO. EXPECT STORMS TO CONTINUE TO DEVELOP AS THE FRONT MOVES EAST INTO A MORE UNSTABLE ATMOSPHERE. MOST OF THE MODELS HAVE REDUCED CAPE VALUES TO BETWEEN 800-1500 J/KG AS THE FRONT NEARS...EXCEPT THE NAM WHICH DEPICTS CAPE VALUES WELL IN EXCESS OF 2000 J/KG OVER NW MISSISSIPPI. 0-6 KM BULK SHEAR VALUES WILL BE NEAR 40 KTS AREA WIDE WITH 0-3 KM LAPSE RATES AS STEEP AS 5.5 C/KM. INCREASING CLOUD COVER DUE TO WAA WILL SERVE AS A HINDRANCE TO SEVERE WEATHER TONIGHT. THE GFS IS MORE AGGRESSIVE WITH THE WAA SHOWERS AND STORMS AND NOT CLEARING OUT BEFORE THE FRONT APPROACHES...WHILE THE NAM... HRRR...AND EURO CLEAR OUT DURING THE EVENING. STORMS WILL BECOME COLD POOL DOMINANT AND BEGIN TO RACE AHEAD OF THE FRONT AS IT APPROACHES OUR REGION. THE MAIN THREAT WITH STORMS ALONG THE FRONTAL BOUNDARY WILL BE SEVERE WINDS DUE TO THEIR LINEAR CONVECTIVE MODE. LARGE HAIL WILL BE A SECONDARY THREAT DUE TO SIGNIFICANT BUOYANCY WITHIN THE HAIL GROWTH ZONES OF THE ATMOSPHERE. MODELS HAVE COME INTO BETTER AGREEMENT WITH THE TIMING OF THE APPROACHING SYSTEM. THE FRONT WILL BEGIN TO APPROACH NORTHEAST ARKANSAS BY 7 PM...THE MS RIVER BETWEEN 11PM AND 1 AM... AND OUT OF OUR COVERAGE AREA BY 5 AM. LINGERING SHOWERS WILL BE POSSIBLE AS A SECONDARY REINFORCING FRONT TRAILS THE LEADING ONE. COOLER DRIER AIR WILL FILTER INTO THE MIDSOUTH BEHIND THE FRONT. HIGHS FRIDAY WILL ONLY REACH THE MID TO UPPER 70S. LOWS FRIDAY NIGHT/SATURDAY MORNING WILL DIVE INTO THE 40S AS NW FLOW INCREASES BRINGING EVEN COOLER AIR INTO THE REGION. WE WILL STRUGGLE TO REACH 70 DEGREES DURING THE DAY ON SATURDAY. ANOTHER COLD FRONT WILL SWEEP THROUGH THE MS RIVER VALLEY EARLY NEXT WEEK. MODELS STILL DISAGREE ON THE TIMING BUT BOTH THE GFS AND EURO AGREE ENOUGH TO INCREASE POPS MONDAY EVENING. JPM3 && .AVIATION... 18Z TAFS PRIMARY CONCERNS REMAIN AFTERNOON SCT TSRA... AND SQUALL LINE ARRIVAL AT MEM DURING THE EVENING ARRIVAL PUSH. 1745Z RADAR SHOWED SCT SHRA/TSRA OVER MUCH OF THE MIDSOUTH. AIRMASS WAS VERY MOIST AND WEAKLY-CAPPED. THERE WAS LITTLE IN THE WAY OF DYNAMIC FORCING IN THE WAY OF FRONTS OR ELEVATED TROFS TO ORGANIZE AFTERNOON TSRA. NONETHELESS...EXPECT CURRENT ACTIVITY TO CONTINUE...WITH SOME INCREASES IN COVERAGE LIKELY. TSRA POTENTIAL SHOULD DECREASE AFTER 22Z... WITH LOSS OF SURFACE HEATING. NAM AND HRRR MODELS HAVE COME INTO BETTER AGREEMENT ON TIMING OF STRONG MIDLEVEL TROF AND SURFACE COLD FRONT. TSRA POTENTIAL WILL INCREASE AT MEM AROUND 03Z...WITH PEAK TSRA CHANCES IN THE 04Z TO 05Z TIME FRAME. NAM MODEL INDICATES TSRA WILL OUTRUN THE COLD FRONT...PERHAPS ALONG AND BEHIND A LEADING OUTFLOW BOUNDARY. AIRMASS SHOULD STABILIZE LIMITING TS POTENTIAL AFTER 07Z...THOUGH SHRA WILL LIKELY CONTINUE. EVENTUAL COLD FRONTAL PASSAGE WILL OCCUR AT MEM AROUND 12Z...TUP AT 16Z. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
1251 PM CDT THU OCT 2 2014 .UPDATE... UPDATED FOR 00Z AVIATION DISCUSSION BELOW. && .PREV DISCUSSION... /ISSUED 958 AM CDT THU OCT 2 2014/ UPDATE... IT IS A WARM...MUGGY EARLY OCTOBER DAY THROUGHOUT THE REGION. A CLUSTER OF WEAK THUNDERSTORMS CONTINUE TO PUSH THROUGH NORTHEAST MISSISSIPPI INTO WEST TENNESSEE AS SOUTHERLY FLOW CONTINUES TO PULL A WARM...MOIST AIR MASS OVER THE REGION. CLOUD COVER WILL CONTINUE TO INCREASE THROUGHOUT THE DAY HOLDING TEMPERATURES BELOW 90 DEGREES. SHORT TERM MODELS HAVE COME INTO BETTER AGREEMENT ON THE TIMING OF A LINE OF STORMS ASSOCIATED WITH A COLD FRONT THAT WILL MOVE THROUGH THE MISSISSIPPI VALLEY REGION TONIGHT. NO CHANGES TO THE FORECAST ARE NEEDED AT THIS POINT. JPM3 PREV DISCUSSION... /ISSUED 625 AM CDT THU OCT 2 2014/ UPDATE...AVIATION DISCUSSION. PREV DISCUSSION... /ISSUED 311 AM CDT THU OCT 2 2014/ A TRICKY SEVERE WEATHER FORECAST FOR THIS AFTERNOON INTO TONIGHT. CURRENTLY...A COLD FRONT STRETCHES FROM KANSAS CITY MISSOURI TO NEAR AMARILLO TEXAS. LIGHT SOUTHERLY WINDS CONTINUE TO BRING AN INCREASE IN MOISTURE FROM THE GULF OF MEXICO. DEWPOINTS ARE CURRENTLY IN THE LOWER TO MID 60S BUT SHOULD JUMP INTO THE UPPER 60S TO LOWER 70S BY THIS AFTERNOON. LOW CLOUDS ARE RAPIDLY DEVELOPING ACROSS LOUISIANA INTO CENTRAL/SOUTHERN MISSISSIPPI. MODELS INDICATE THE CLOUDS SHOULD SPREAD ACROSS THE CWA BETWEEN 6AM-9AM. LATEST HRRR SHOWS SHOWERS SHOULD START POPPING ACROSS NORTH MISSISSIPPI BY 8 AM. BY 11AM-1PM...SHOWERS AND THUNDERSTORMS WILL RAPIDLY DEVELOP ACROSS MOST OF THE CWA AND WILL CONTINUE THROUGH THE REST OF THE AFTERNOON. THE LATEST GFS..NAM...AND ECMWF SEEM TO FALL IN LINE IN WHAT THE HRRR IS SHOWING THUS HAVE INCREASED POPS TO 60S ACROSS MUCH OF THE CWA FROM MID-MORNING INTO THE AFTERNOON. THE LOW CLOUDS MAY HANG TOUGH INTO THE AFTERNOON HOURS. THIS MAY HINDER ANY THUNDERSTORMS FROM BECOMING STRONG OR SEVERE AT LEAST DURING THE AFTERNOON HOURS. WITH ALL THE CONVECTION AND CLOUD COVER EXPECTED...HAVE KNOCKED DOWN HIGHS TODAY A TAD. DON/T REALLY SEE ANY LOCATION HITTING 90 TODAY. HIGHS SHOULD STAY IN THE MID TO UPPER 80S. SQUALL LINE IS STILL EXPECTED TO DEVELOP ALONG THE FRONT DURING THE AFTERNOON AND LATEST HRRR SHOWS IT STRETCHING FROM TULSA OKLAHOMA TO NEAR ABILENE TEXAS AROUND 2 PM. THE LINE WILL PROGRESS EASTWARD DURING THE REST OF THE AFTERNOON INTO THE EVENING HOURS. THE LINE WILL LIKELY OUTRACE THE FRONT BY THE EVENING HOURS. EXPECT BY THE TIME IT REACHES THE MIDSOUTH...IT MAY ENCOUNTER AN ATMOSPHERE AT LEAST SLIGHT WORKED OVER FROM CONVECTION THAT WILL OCCUR TODAY AND NOT AS UNSTABLE AS PREVIOUSLY THOUGHT A FEW DAYS AGO DUE TO CLOUD COVER. CAPE VALUES MAY GET TO 1500 J/KG WHICH IS STILL DECENT BUT NOT LIKE 2200 J/KG OR GREATER THAT THE NAM HAS BEEN SHOWING. MODELS ALSO CONTINUE TO BE A LITTLE SLOWER WITH TIMING. LINE MAY NOT GET INTO NORTHEAST ARKANSAS UNTIL CLOSER TO 9-10 PM. THUS INSTABILITY WILL BE WANING FROM LOSS OF DAYTIME HEATING. STILL EXPECT EASTERN ARKANSAS AND THE MISSOURI BOOTHEEL TO SEE THE BEST CHANCE OF SEEING SEVERE STORMS BUT REALLY EXPECT LINE TO START WEAKENING AS IT PUSHES EAST ESPECIALLY ONCE IT PUSHES EAST OF THE MISSISSIPPI RIVER. MAIN THREAT FROM THE LINE WILL BE DAMAGING WINDS AND LARGE HAIL. SINCE TIMING IS SLOWER HAVE HAD TO UPDATE POPS FOR FRIDAY TO KEEP THEM IN LONGER. NORTH MISSISSIPPI COULD SEE SOME REDEVELOPMENT OF THUNDERSTORMS ALONG THE FRONT DURING THE AFTERNOON HOURS. WOULD NOT BE SURPRISED IF SOME OF THESE BECAME STRONG WITH GUSTY WINDS AND SMALL HAIL. HIGH PRESSURE WILL BUILD INTO THE MIDSOUTH FOR THE WEEKEND AND WILL BRING BEAUTIFUL AUTUMN TEMPERATURES. HIGHS ON SATURDAY WILL BE IN THE MID TO UPPER 60S. LOWS SATURDAY NIGHT WILL DROP DOWN INTO THE UPPER 30S TO MID 40S. TEMPERATURES WILL JUMP BACK INTO THE 70S ON SUNDAY AS THE HIGH SHIFTS EAST. MODELS STILL DIFFER ON TIMING OF THE NEXT COLD FRONT FOR EARLY NEXT WEEK. THE ECMWF INDICATES FRONT WILL COME THROUGH SUNDAY NIGHT THROUGH MONDAY NIGHT. GFS HAS TIMING OF MONDAY NIGHT INTO TUESDAY. FOR NOW HAVE LEFT POPS AS IS WITH SMALL CHANCES FOR SHOWERS AND THUNDERSTORMS FOR MONDAY INTO TUESDAY. DON/T REALLY EXPECT ANY COOL DOWN BEHIND THE FRONT AS AN UPPER RIDGE WILL BEGIN TO BUILD INTO THE AREA BEHIND IT. TEMPERATURES WILL LIKELY BE BACK INTO THE 80S BY WEDNESDAY. KRM && .AVIATION... 18Z TAFS PRIMARY CONCERNS REMAIN AFTERNOON SCT TSRA... AND SQUALL LINE ARRIVAL AT MEM DURING THE EVENING ARRIVAL PUSH. 1745Z RADAR SHOWED SCT SHRA/TSRA OVER MUCH OF THE MIDSOUTH. AIRMASS WAS VERY MOIST AND WEAKLY-CAPPED. THERE WAS LITTLE IN THE WAY OF DYNAMIC FORCING IN THE WAY OF FRONTS OR ELEVATED TROFS TO ORGANIZE AFTERNOON TSRA. NONETHELESS...EXPECT CURRENT ACTIVITY TO CONTINUE...WITH SOME INCREASES IN COVERAGE LIKELY. TSRA POTENTIAL SHOULD DECREASE AFTER 22Z... WITH LOSS OF SURFACE HEATING. NAM AND HRRR MODELS HAVE COME INTO BETTER AGREEMENT ON TIMING OF STRONG MIDLEVEL TROF AND SURFACE COLD FRONT. TSRA POTENTIAL WILL INCREASE AT MEM AROUND 03Z...WITH PEAK TSRA CHANCES IN THE 04Z TO 05Z TIME FRAME. NAM MODEL INDICATES TSRA WILL OUTRUN THE COLD FRONT...PERHAPS ALONG AND BEHIND A LEADING OUTFLOW BOUNDARY. AIRMASS SHOULD STABILIZE LIMITING TS POTENTIAL AFTER 07Z...THOUGH SHRA WILL LIKELY CONTINUE. EVENTUAL COLD FRONTAL PASSAGE WILL OCCUR AT MEM AROUND 12Z...TUP AT 16Z. PWB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
1107 AM CDT THU OCT 2 2014 .UPDATE... A STRONG SHORTWAVE TROUGH CONTINUES TO ROTATING EAST-SOUTHEAST ACROSS THE TX/OK PANHANDLES LATE THIS MORNING...WITH A PRE-FRONTAL SURFACE TROUGH NOW SWEEPING THROUGH AREAS FROM WICHITA FALLS TO NEAR ABILENE. THE TRUE COLD FRONT REMAINS FURTHER WEST FROM VERNON TO SWEETWATER/SNYDER AREAS PER CAA NOTED AND TEMPERATURES FALLING THROUGH THE 60S INTO THE 50S ACROSS THE TX PANHANDLE. THERMODYNAMICALLY THE 12Z FWD SOUNDING HAD A MODEST CAP WITH STEEP LAPSE RATES NOTED BETWEEN 650-800MB. THE CAP SHOULD CONTINUE TO LIFT...MOISTEN AND WEAKEN WITH THE APPROACH OF THE STRONG LARGE-SCALE ASCENT FROM THE NORTHWEST BY EARLY-MID AFTERNOON. UNTIL THEN...A FEW SHOWERS AND NON-SEVERE STORMS WILL CONTINUE UNDERNEATH THE LIFTING CAPPING INVERSION FROM JUST WEST THROUGH NORTHEAST OF THE IMMEDIATE DFW METRO AREA. THE ACTION AREA THROUGH 19Z OR SO WILL BE ACROSS OUR OUR NORTHWEST COUNTIES THROUGH EARLY AFTERNOON...AS THIS WILL BE WHERE THE STRONGEST ASCENT AND BREAKING OF THE CAPPING INVERSION OCCURS WITH THE ARRIVAL OF THE PRE-FRONTAL SURFACE TROUGH. A FEW DISCRETE STRONG TO SEVERE STORM WILL LIKELY FORM ON THIS FEATURE. THE COLD FRONT WILL LIKELY SPEED UP AND TAKE OVER THIS SURFACE TROUGH FROM NEAR HAMILTON UP THROUGH DALLAS-FORT WORTH...AND TOWARD GAINESVILLE AND SHERMAN BY MID AFTERNOON. AS THIS OCCURS SIMULTANEOUSLY WITH THE ARRIVE OF THE VIGOROUS SHORTWAVE DISTURBANCE...EXPECT A RAPID INCREASE OF STORMS TO ZIPPER SOUTHWEST AS FAR SOUTH AS HAMILTON TO WACO AND POSSIBLY BELL COUNTY. WITH THESE TRENDS IN MIND...HAVE DRUG THE HIGHER CHANCE TO LIKELY POPS DOWN INTO PARTS OF CENTRAL TEXAS AS WELL FOR THE LATER AFTERNOON HOURS. THE MAIN SEVERE THREATS STILL APPEAR TO BE HAIL...DAMAGING WINDS TO 70 MPH AND FREQUENT LIGHTNING...THOUGH EARLY ON THE EVENT WHEN STORMS ARE MORE DISCRETE YOU CANNOT RULE OUT A BRIEF TORNADO WITH ANY OUTFLOW BOUNDARY INTERACTIONS. HAVE HELD ONTO TRENDS FOR THE EVENING INTO THE OVERNIGHT HOURS WITH NO CHANGES...AS THE FRONT AND SYSTEM MOVE PROGRESSIVELY ACROSS THE REGION. WITH MORE CLOUD COVER THAN EXPECTED IN THE WARM SECTOR AND A SLIGHTLY FASTER ARRIVAL OF THE COLD FRONT...I LOWERED HIGH TEMPS ACROSS THE FAR WEST AND NORTHWEST AREAS TO HIGHS IN THE MID-UPPER 80S VERSUS LOWER 90S. 05/ && .AVIATION... /ISSUED 1028 AM CDT THU OCT 2 2014/ HRRR AND RAP ARE NOW SHOWING SCATTERED CONVECTION BREAKING OUT AROUND NOON IN METROPLEX AREA. COVERAGE WILL BE LOW WITH THESE DISCRETE CELLS BUT HAVE ADDED VCTS AFTER 17Z. AS I WRITE THIS WE HAVE ONE CELL IN DENTON COUNTY THAT NOW HAS CLOUD-CLOUD LIGHTNING...AND ONE IN HOOD COUNTY THAT VERTICAL INTEGRATED ICE IS SHOWING COMING CLOSE TO HAVING LIGHTNING. BEST CHANCE FOR TSRA STILL AHEAD OF THE FRONT LASTING FROM 20Z-22Z. 84 && .PREV DISCUSSION... /ISSUED 331 AM CDT THU OCT 2 2014/ WATER VAPOR LOOP SHOWS A PRONOUNCED SHORTWAVE TROUGH OVER NEW MEXICO RAPIDLY MOVING EASTWARD TOWARD THE REGION. FORCING FOR ASCENT AHEAD OF THIS FEATURE IS ALREADY REACHING THE REGION...AS AIRCRAFT DATA INDICATES LIFTING AND DYNAMIC COOLING OF THE MID LEVEL TEMPERATURE PROFILE. WHERE ENOUGH MOISTURE EXISTS ALOFT...ACROSS THE NW ZONES AND OKLAHOMA...THIS LIFT IS ALLOWING ELEVATED PARCELS TO REACH THEIR LFC AND CONVECT. THIS SCATTERED ELEVATED CONVECTION WILL REMAIN PRIMARILY NORTH OF THE REGION THIS MORNING...BUT THE NORTHWEST AND NORTHERN ZONES WILL HAVE A CHANCE OF MORNING SHOWERS OR STORMS. THE COLD FRONT IS NOW ENTERING THE TEXAS PANHANDLE AND IS FORECAST TO REACH THE NW ZONES BY MIDDAY. MODEL GUIDANCE IS AN HOUR OR TWO FASTER WITH THE FRONT...BUT OVERALL THERE IS LITTLE CHANGE TO THE FORECAST THINKING OF THE LAST FEW DAYS. AHEAD OF THE FRONT...SOUTH TO SOUTHWEST WINDS OF 10 TO 20 MPH WILL ENSURE A WARM MORNING AND ONCE THE LOW STRATUS SCATTERS OUT BY MIDDAY...SUNSHINE WILL BOOST TEMPS INTO THE LOW TO MID 90S OVER THE REGION. THESE HOT TEMPS AND DEWPOINTS NEAR 70 OCCURRING IN CONJUNCTION WITH DYNAMIC COOLING ALOFT WILL RESULT IN A MODERATELY UNSTABLE AIRMASS DEVELOPING THIS AFTERNOON WITH CAPE REACHING 2000-2500 J/KG. WHILE A FAIRLY STRONG INVERSION NEAR 850MB WILL CAP OFF CONVECTIVE POTENTIAL EARLY IN THE DAY...THE COMBINATION OF DYNAMIC LIFT AHEAD OF THE SHORTWAVE TROUGH...CONVERGENCE ALONG THE FRONT...AND AFTERNOON HEATING WILL ALL WORK TO ERODE CONVECTIVE INHIBITION OVER THE AREA. SURFACE BASED CONVECTION IS EXPECTED TO FORM ALONG THE FRONT OVER THE NW ZONES AROUND 1 PM AS THE CAP BEGINS TO BREAK. CONVECTION WILL CONTINUE TO DEVELOP SOUTHWARD ALONG THE FRONT THROUGH THE MID-LATE AFTERNOON HOURS AS IT MARCHES SOUTHEAST INTO THE CENTRAL ZONES. WE EXPECT FROPA AROUND 3 PM NEAR GAINESVILLE...5 PM NEAR DFW...AND 7PM NEAR WACO. WHEN THE FRONT CROSSES THE I-35 CORRIDOR A SQUALL LINE WILL BEGIN TO TAKE SHAPE...WHICH MEANS THERE MAY STILL BE A FEW GAPS IN THE LINE AT THIS TIME. A FULLY DEVELOPED AND MATURE SQUALL LINE WILL EXIST AS THE FRONT MOVES EAST OF THE I-35 CORRIDOR EARLY THIS EVENING...AND IT APPEARS THE THREAT FOR DAMAGING WINDS IS HIGHEST IN THIS REGION. THE CAP WILL BE A LITTLE STRONGER OVER THE WESTERN AND SOUTHWESTERN ZONES...AND ACTIVITY WILL LIKELY BE MORE ISOLATED THERE. WHERE CONVECTION IS MORE ISOLATED...SUPER-CELLULAR STORM MODE IS FAVORED...WHICH MEANS THERE IS AN ENHANCED LARGE HAIL THREAT IN ADDITION TO A WIND THREAT. WHILE LOW LEVEL WIND PROFILES DO NOT APPEAR FAVORABLE FOR LOW LEVEL ROTATION...SURFACE BASED SUPERCELLS CAN STILL PRODUCE ISOLATED TORNADOES GIVEN THE RIGHT MESOSCALE CONDITIONS...BUT THIS CANNOT BE FORECAST RELIABLY AT THIS TIME RANGE. THE FRONT AND LINE OF STORMS WILL RAPIDLY CLEAR THE REGION FROM NORTHWEST TO SOUTHEAST THIS EVENING. DRIER AND SLIGHTLY COOLER AIR WILL MOVE INTO THE REGION OVERNIGHT...BUT NORTHERLY WINDS WILL NOT REALLY INCREASE UNTIL FRIDAY WHEN A STRONGER HIGH PRESSURE SURGE ARRIVES. HIGHS FRIDAY WILL BE COOLER AND GENERALLY TOP OUT NEAR 80 IN THE NORTH AND THE MID 80S SOUTH. THE SURFACE HIGH WILL SETTLE IN RIGHT OVER THE CWA BY SUNRISE SATURDAY AND WINDS WILL GO CALM. WITH DEWPOINTS BY THIS TIME IN THE 30S AND 40S...LOWS SATURDAY MORNING SHOULD REACH THE 40S FOR A LARGE PORTION OF THE CWA...WITH LOW 50S FOR THE DFW AREA AND THE SOUTHEAST CWA. SATURDAY WILL BE SUNNY AND PLEASANT WITH HIGHS TOPPING OUT NEAR 80...BUT WINDS WILL SWITCH TO THE SOUTH BY SATURDAY EVENING. INCREASING MOISTURE AND A MODERATION OF TEMPS BACK ABOVE NORMAL WILL OCCUR SUNDAY INTO EARLY NEXT WEEK. THE 00Z ECMWF HAS AN OUTLIER SOLUTION OF A STRONG SHORTWAVE ROTATING THROUGH IN NORTHWEST FLOW ALOFT ON MONDAY WHICH BRINGS ANOTHER WEAK FRONT AND A CHANCE OF RAIN TO THE AREA. THE GFS/CANADIAN/UKMET ARE MUCH WEAKER WITH THIS ENERGY AND THEREFORE SHOW DRY WEATHER WITH HIGH TEMPS WARMING INTO THE 90S WITH LOWS IN THE 60S AND 70S. WILL KEEP FORECAST THE DRY BUT AS A NOD TO THE ECMWF POTENTIAL WILL NUDGE HIGH TEMPS DOWNWARD INTO THE MID TO UPPER 80S FOR NEXT WEEK INSTEAD OF THE CLIMATOLOGICALLY BOLD FORECAST OF LOWER 90S. TR.92 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 91 59 82 50 80 / 70 20 0 0 0 WACO, TX 94 58 84 49 81 / 60 40 5 0 0 PARIS, TX 90 57 78 45 76 / 80 60 0 0 0 DENTON, TX 90 54 81 43 80 / 70 10 0 0 0 MCKINNEY, TX 91 56 81 43 78 / 80 30 0 0 0 DALLAS, TX 92 60 82 51 80 / 80 30 0 0 0 TERRELL, TX 93 59 82 48 79 / 80 50 0 0 0 CORSICANA, TX 93 61 83 49 79 / 60 60 5 0 0 TEMPLE, TX 94 60 85 50 81 / 50 50 5 0 0 MINERAL WELLS, TX 90 54 82 44 81 / 40 10 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 84/05
FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND FRIDAY ISSUED AT 337 PM CDT THU OCT 2 2014 RAIN WAS THE MAIN CONCERN FOR THE EVENING AND OVERNIGHT...WITH TEMPERATURES THE ISSUE DURING THE DAY ON FRIDAY. SHOWERS AND A FEW THUNDERSTORMS...ASSOCIATED WITH A MID LEVEL SHORT WAVE AND SURFACE LOW PRESSURE SYSTEM THAT WAS MOVING TOWARD WISCONSIN FROM THE SOUTHWEST...WERE MOVING INTO WISCONSIN FROM IOWA AND NORTHERN ILLINOIS. ANOTHER MID LEVEL SHORT WAVE AND A COLD FRONT WERE APPROACHING FROM THE WEST...BRINGING SHOWERS INTO THE STATE FROM MINNESOTA. THERE WERE ALSO SCATTERED SHOWERS...AND SOME THUNDER...AHEAD OF AND BETWEEN THE TWO SYSTEMS. GUIDANCE WAS SHOWING QPF INTO THE SOUTHERN PART OF THE FORECAST AREA LATE THIS AFTERNOON/EARLY THIS EVENING. HOWEVER...THE MESOSCALE HRRR FROM 16Z HAD THE RAIN THAT WAS MOVING IN FROM THE SOUTH MAINLY IMPACTING AREAS FROM THE FOX VALLEY EAST TO THE LAKE AS THE RAIN TO THE WEST MOVES INTO CENTRAL AND NORTH CENTRAL WISCONSIN DURING THE EVENING. LIGHTNING DETECTION HAD SOME CLOUD TO GROUND STRIKES ALONG THE EASTERN PART OF THE MINNESOTA/IOWA BORDER...WHERE LOCAL MESOANALYSIS GRAPHICS SHOWED RATHER LOW MUCAPE WITH AROUND ZERO CIN. OTHER LOCATIONS IN IOWA AND NORTHERN ILLINOIS...WITH HIGHER MUCAPE AND LITTLE OR NO CIN...DID NOT HAVE ANY CLOUD TO GROUND LIGHTNING DETECTED WITH IT. HAVE GONE WITH INCREASING POPS FROM THE SOUTH AND WEST TONIGHT AS THE LOW MAKES ITS WAY ACROSS THE FORECAST AREA AND THE FRONT PUSHES IN FROM THE WEST. HAVE DECREASING POPS FROM WEST TO EAST ON FRIDAY AS THE COLD FRONT CONTINUES EASTWARD. DID MENTION A CHANCE FOR THUNDER LATE TODAY INTO TONIGHT BUT THINKING IT SHOULD BE MAINLY RAIN SHOWERS. THE STRONG COLD ADVECTION WITH THE FRONTAL PASSAGE...ALONG WITH PLENTY OF CLOUDS...WILL KEEP TEMPERATURES FROM WARMING UP MUCH DURING THE DAY ON FRIDAY IF THEY MANAGE TO WARM AT ALL. SEEMS A LITTLE EARLY IN THE SEASON FOR FALLING TEMPERATURES DURING THE DAY BUT IT IS PAST THE AUTUMNAL EQUINOX AND THE COLD ADVECTION IS STRONG. HAVE NEARLY STEADY TEMPERATURES GOING THROUGH MID MORNING...BEFORE SLOWLY FALLING THE REST OF THE DAY. .LONG TERM...FRIDAY NIGHT THROUGH THURSDAY ISSUED AT 337 PM CDT THU OCT 2 2014 PCPN TRENDS AND TYPE FOR THE WEEKEND...AND TEMPERATURE TRENDS THROUGH THE EXTENDED PERIOD...ARE THE MAIN FCST CONCERNS. A STRONG UPPER LOW WILL TRACK THROUGH CENTRAL WI AND THE SOUTHERN FOX VALLEY ON FRIDAY NIGHT...AS A SECONDARY COLD FRONT SWEEPS SOUTHEAST ACROSS THE FORECAST AREA. WILL HAVE LIKELY POPS MOVG INTO NC/C WI LATE FRIDAY EVG...AND PROGRESSING TO JUST NW OF THE FOX VALLEY BY DAYBREAK SATURDAY. THE UPPER LOW AND FRONT WILL EXIT SATURDAY MORNING...CAUSING SHOWERS TO DECREASE OVER EASTERN WI. PCPN TYPE WILL PROBABLY BE MIXED RAIN/SNOW OVER ABOUT THE SW THIRD OF THE CWA FRIDAY NIGHT...WHERE MODELS SHOW THE COLDEST POCKET OF AIR IN ASSOCIATION WITH THE UPPER LOW. LITTLE OR NO ACCUMULATION IS ANTICIPATED. A WEAK THERMAL RIDGE IS EXPECTED TO KEEP PCPN ALL RAIN OVER THE FAR NORTH. GENERALLY DRY CONDITIONS ARE ANTICIPATED FROM SATURDAY AFTERNOON THROUGH SUNDAY...WITH THE EXCEPTION OF FAR NC WI SAT AFT/NGT... WHERE SCT LAKE ENHANCED SHOWERS ARE POSSIBLE. THE AIR MASS WILL BE COLD ENOUGH TO SUPPORT SNOW SHOWERS ON SAT NGT. NW FLOW AND ASSOCIATED COOL TEMPERATURES WILL CONTINUE THROUGH ABOUT TUESDAY. THE BEST CHANCE OF PCPN IS EXPECTED ON MONDAY NIGHT...AS A SHARP UPPER TROF AND ASSOCIATED COLD FRONT MOVE THROUGH. WITH A DRY AIR MASS IN PLACE...POPS WILL ONLY BE IN THE CHC CATEGORY. ZONAL FLOW ALOFT IS EXPECTED TO RETURN BY MIDWEEK...WITH A GRADUAL MODERATION IN TEMPERATURES...AND GENERALLY DRY CONDITIONS. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 103 PM CDT THU OCT 2 2014 CIGS WERE MVFR ACROSS MOST OF THE AREA AT MIDDAY. THE EXCEPTIONS WERE NEAR LAKE MICHIGAN AND THE BAY...AND NORTH OF HIGHWAY 8. VSBYS WERE VFR IN MUCH OF CENTRAL AND PARTS OF NORTH CENTRAL WISCONSIN...BUT MAINLY MVFR ACROSS THE REST OF THE AREA IN HZ OR BR. THERE WERE A FEW SHOWERS MOVING INTO MANITOWOC COUNTY AT MIDDAY...BUT THE MAIN AREA OF SHOWERS WAS IN IOWA AND NORTHERN ILLINOIS AND HEADED TOWARD THE AREA. THE SHOWERS SHOULD BE MOVING INTO CENTRAL AND EAST CENTRAL LATER IN THE AFTERNOON AND CONTINUING NORTHEAST. ONCE THE SHOWERS ARRIVE VSBYS MAY START OUT MVFR...WITH VFR CONDITIONS ALSO POSSIBLE AT TIMES...BUT CIGS AND VSBYS SHOULD BECOME IFR IN RAIN DURING THE EVENING. THUNDERSTORMS CANNOT BE RULED OUT...BUT CHANCES WERE NOT HIGH ENOUGH TO ADD THEM TO THE TAFS. AS THE SURFACE LOW AND FRONT MAKE THEIR WAY TO THE EAST CIGS SHOULD IMPROVE A BIT AND WINDS WILL SHIFT TO THE WEST AND INCREASE BY FRIDAY MORNING. && .GRB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM.....MG LONG TERM......KIECKBUSCH AVIATION.......MG
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
302 PM CDT THU OCT 2 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 302 PM CDT THU OCT 2 2014 CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING ALONG BOTH THE WEST AND EAST COASTS OF NORTH AMERICA AND LONG WAVE TROUGHING DEVELOPING IN-BETWEEN. THE SOUTHERN STREAM PORTION OF THIS LONG WAVE TROUGH FEATURES A POTENT SHORTWAVE OVER THE SOUTHERN PLAINS...WHILE THE NORTHERN STREAM CONSISTED OF A TROUGH DROPPING THROUGH SASKATCHEWAN AND MONTANA. ANOTHER SHORTWAVE WAS PRESENT ALONG THE MN/SD BORDER. DPVA AHEAD OF THIS SHORTWAVE AND MID LEVEL FRONTOGENESIS HAS SUPPORTED A BAND OF SHOWERS FROM NW IA INTO CENTRAL AND NE MN. AHEAD OF THE SOUTHERN PLAINS SHORTWAVE...A STREAM OF 850MB MOISTURE TRANSPORT HAS HELPED SPREAD 1.5-2 INCH PRECIPITABLE WATER THROUGH MO...IL AND NOW APPROACHING SOUTHERN WI. THIS MOISTURE...THE TRANSPORT...DPVA FROM THE SOUTHERN PLAINS SHORTWAVE AND 1000-2000 J/KG MUCAPE ACCOMPANYING THE HIGHER MOISTURE HAS SUPPORTED NUMEROUS SHOWERS AND STORMS MOSTLY SOUTH OF THE FORECAST AREA. HOWEVER...SOME HAVE BEGUN TO SPREAD NORTH INTO THE SOUTHERN HALF OF THE FORECAST AREA. OTHERWISE...THE FORECAST AREA SITS IN A MASS OF LOW STRATUS...AIDED BY BEING IN A WEAK PRESSURE GRADIENT WITH A SURFACE TROUGH IN PLACE. TO THE WEST...THOUGH...A WEDGE OF CLEAR SKIES EXISTS ACROSS THE EASTERN DAKOTAS...AHEAD OF A SIGNIFICANT COLD FRONT COMING THROUGH THE WESTERN DAKOTAS. OVER THE NEXT 24 HOURS...THE TROUGH OVER SASKATCHEAWN AND MONTANA REMAINS PROGGED TO DIG THROUGH THE CENTRAL U.S. AND MAKE ITS WAY INTO THE FORECAST AREA. BY 00Z SAT...MOST MODELS HAVE AN UPPER LOW SITUATED RIGHT ON TOP OF LSE. THIS UPPER TROUGH WILL HELP PUSH THE MOIST FLOW REGIME CURRENTLY SPREADING NORTH TOWARDS THE FORECAST AREA OFF TO THE NORTHEAST. HOWEVER...AT THE SAME TIME...IT SHOULD BRING AN AIRMASS IN MORE SIMILAR TO LATE OCTOBER/EARLY NOVEMBER. FOR TONIGHT...MUCH OF THE 850MB MOISTURE TRANSPORT IS PROGGED TO STAY SOUTH AND EAST OF THE FORECAST AREA...WHICH WILL HELP KEEP THE HIGHER PRECIPITABLE WATER AND INSTABILITY ACCOMPANYING IT AWAY. HOWEVER...WE STILL HAVE TO CONTEND WITH THE SHORTWAVE ALONG THE MN/SD BORDER HEADING EAST TOWARDS THE AREA. DPVA FROM THE SHORTWAVE INTERACTING WITH 1-1.5 INCH PRECIPITABLE WATER AHEAD OF IT...ALONG WITH SOME MID LEVEL FRONTOGENESIS SHOULD HELP BRING SHOWERS TO MUCH OF THE FORECAST AREA THIS EVENING. ANTICIPATING MUCH OF THE RAIN IN THE LIGHT TO POSSIBLY MODERATE INTESITY...GIVEN THE UNSTABLE AIR STAYING AWAY FROM THE AREA. CANT RULE OUT A FEW THUNDERSTORMS AS WELL GIVEN PRESENCE OF WEAK INSTABILITY PROGGED. THERE HAS BEEN A TREND FOR THE PRECIPITATION TO GET OUT OF THE FORECAST AREA QUICKER IN 02.06Z/02.12Z GUIDANCE...SO HAVE ADJUSTED CHANCES TOWARDS A DRIER OVERNIGHT. SKIES COULD CLEAR OUT FOR A TIME OVERNIGHT AS WELL AS THE CURRENT WEDGE OF CLEARING IN THE EASTERN DAKOTAS MOVES IN. ON FRIDAY...DESPITE THE PRESENCE OF THE UPPER TROUGH MOVING IN...SOUNDINGS SUGGEST MOSTLY A SUBSIDENT REGIME IN PLACE. THIS WILL HELP KEEP MUCH OF THE FORECAST AREA DRY. HOWEVER...AS WE APPROACH 00Z SAT...ANOTHER BAND OF FRONTOGENETICAL FORCING ON THE NORTHWEST SIDE OF THE AFOREMENTIONED UPPER LOW THAT FORMS COULD BEGIN TO APPROACH FAR NORTHWEST SECTIONS OF THE FORECAST AREA. HAVE INCLUDED 20 PERCENT CHANCES JUST IN CASE. TEMPERATURES AND WINDS ARE GOING TO BE THE BIG DEAL FOR FRIDAY...THOUGH. A SUSTAINED 30-40 KT 925MB NORTHWEST WIND WILL HELP DRIVE 925MB TEMPS DOWN FROM 8-12C AT 09Z FRI TO 3-6C BY 18Z FRI...AND PERHAPS AS LOW AS 2C BY 00Z SAT. THUS...TEMPERATURES SHOULD EITHER HOLD STEADY OR SLOWLY FALL THROUGH THE DAY. MANY LOCATIONS ARE LIKELY TO STAY IN THE 40S FOR MUCH OF THE DAY WITH VALLEY AREAS STANDING THE BEST CHANCE TO GET ABOVE 50. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 302 PM CDT THU OCT 2 2014 A POTENT AND FAST MOVING SHORTWAVE PUSHES THROUGH THE FORECAST AREA FRIDAY NIGHT BRINGING WITH IT SOME OF THE CHILLIEST AIR OF THE THE FALL SO FAR. PRECIPITATION SHOULD PUSH INTO NORTHWEST SECTIONS OF THE FORECAST AREA EARLY IN THE EVENING THEN SWINGING ACROSS THE REMAINDER OF THE FORECAST AREA DURING THE LATE EVENING AND OVERNIGHT HOURS. THE PRECIPITATION LOOKS TO START OUT AS LIGHT RAIN BUT WILL THEN SWITCH OVER TO A PERIOD OF LIGHT SNOW OR A RAIN/SNOW MIX. IN FACT..THE SNOWFALL RATES COULD BE HIGH ENOUGH TO ACCUMULATE A SLUSHY 1/2 INCH OR SO ON ELEVATED SURFACES AWAY FROM VALLEY LOCATIONS. IF THIS SNOWFALL WOULD OCCUR IT WOULD BE THE 4TH EARLIEST MEASURABLE SNOWFALL FOR ROCHESTER...AND IF SNOW IS MEASURED AT LA CROSSE IT WOULD BE THE 3RD EARLIEST. WINDY CONDITIONS WILL PERSIST FRIDAY NIGHT WITH A TIGHT PRESSURE GRADIENT IN PLACE OVER THE REGION. WE WILL SEE THE WINDS SWITCH TO NORTHWEST ON THE BACK SIDE OF THE WAVE. THE COMBINATION OF THE NORTHWEST WINDS OF 15 TO 25 MPH WITH GUSTS AROUND 40 MPH... AND FALLING SNOW COULD CAUSE SOME BRIEF VISIBILITY RESTRICTIONS SO WE WILL HAVE TO KEEP AN EYE ON THIS POTENTIAL. IT WILL BE CHILLY FRIDAY NIGHT WITH TEMPERATURES FALLING INTO THE 30S ACROSS THE ENTIRE FORECAST AREA. SATURDAY WILL BE A RATHER RAW DAY OVER THE REGION...AT LEAST COMPARED TO WHERE WE WERE LAST WEEKEND. BREEZY NORTHWEST WINDS WILL PERSIST OVER THE REGION AND TEMPERATURES WON/T MAKE IT OUT OF THE 40S. A FEW RAIN SHOWERS ARE ALSO POSSIBLE ESPECIALLY OVER PORTIONS OF NORTHERN IN CENTRAL WISCONSIN. THOSE WITH COLD SENSITIVE VEGETATION SHOULD TAKE THE PROPER PRECAUTIONS TO PROTECT IT WITH TEMPERATURES EXPECTED TO FALL INTO THE 30S FRIDAY NIGHT...SATURDAY NIGHT...AND AGAIN SUNDAY NIGHT. IN FACT...SOME LOCATIONS OVER CENTRAL INTO NORTHERN WISCONSIN WILL LIKELY SEE A FREEZE OVER THE WEEKEND. TEMPERATURES OVER THESE AREAS COULD DIP INTO THE UPPER 20S...PARTICULARLY SATURDAY NIGHT. COOL NORTHWEST FLOW PERSISTS OVER THE REGION ON SATURDAY WITH PARTLY SUNNY SKIES EXPECTED. LOW PRESSURE REMAINS PARKED OVER CENTRAL ONTARIO WITH A DEEP TROUGH PERSISTING ACROSS THE UPPER MIDWEST AND MUCH OF THE EASTERN CONUS. SOME RELIEF FROM THE COOL WEATHER IS IN STORE FOR THE REGION BY THE MIDDLE OF NEXT WEEK AS THE TROUGH SHIFTS EAST AND ZONAL FLOW SETS UP. HIGHS SHOULD REBOUND INTO THE 60S WEDNESDAY INTO THURSDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1228 PM CDT THU OCT 2 2014 VLIFR/LIFR CONDITIONS STILL SIT AT RST AS DAYTIME HEATING HAS BEEN SLOW AT MIXING OUT THE FOG PRESENT THERE. ANTICIPATING SOME SLOW IMPROVEMENT TO BOTH CEILINGS AND VISIBILITIES THROUGH THE AFTERNOON AS DAYTIME HEATING CONTINUES TO WORK ON THE FOG AND STRATUS. SHOWERS MOVING IN LATER THIS AFTERNOON COULD HELP TO IMPROVE VISIBILITY SOME...THOUGH. AT LSE...VISIBILITIES ARE ALREADY VFR WITH CEILINGS FLIRTING WITH MVFR. ANTICIPATING CEILINGS THERE TO RISE FULLY TO MVFR BY 20Z...EVEN WITH SHOWERS MOVING IN. A FRONTAL PASSAGE LOOKS TO OCCUR AROUND 00Z...WHICH PRESSURES RISING IN ITS WAKE MAY ALLOW FOR A PERIOD OF NORTHWEST 20 KT GUSTS THIS EVENING. CEILINGS APPEAR TO HOLD STEADY THROUGH THE EVENING...THOUGH THERE COULD BE A RISE DUE TO THE NORTHWEST WIND. A BETTER SHOT FOR RISING CEILINGS COMES AFTER 06Z AS A WEDGE OF CLEARING OVER THE EASTERN DAKOTAS MOVES IN. HAVE TRIED TO TIME THAT CLEARING IN THE TAF...BUT MAY NEED SOME ADJUSTMENT IN LATER FORECASTS. ANOTHER COLD FRONTAL PASSAGE WILL MOVE THROUGH THE TAF SITES AROUND 12Z FRIDAY. A TIGHT PRESSURE GRADIENT IN ITS WAKE PLUS COLD AIR FLOWING IN SHOULD HELP KICK UP THE NORTHWEST WINDS TO 10 TO 20 KT...WITH GUSTS OF 25-30 KT BY MID-DAY. A PERIOD OF MVFR CEILINGS LOOKS LIKELY TOO IN THE WAKE OF THE FRONT...WITH DAYTIME MIXING INCREASING THE CEILING THROUGH THE MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...WETENKAMP AVIATION...AJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1228 PM CDT THU OCT 2 2014 .UPDATE... ISSUED AT 955 AM CDT THU OCT 2 2014 DENSE FOG ADVISORY HAS BEEN EXTENDED FOR SOUTHEAST MN AND BUFFALO COUNTY IN WISCONSIN AS CONDITIONS HAVE BEEN SLOW TO IMPROVE THIS MORNING. SOUNDINGS SHOW STEEP LOW LEVEL INVERSION CONTINUING THROUGH NOON AND WITH TROUGH AXIS RIGHT THROUGH THE REGION...LITTLE MIXING EXPECTED TO HELP BREAK THINGS UP. FOR NORTHEAST IOWA...OBSERVATIONS AND CALLS TO PARTNER GROUPS INDICATE THAT CONDITIONS HAVE IMPROVED SUCH THAT THE ADVISORY CAN BE ALLOWED TO EXPIRE. && .SHORT TERM...(TODAY THROUGH TONIGHT) ISSUED AT 325 AM CDT THU OCT 2 2014 IMMEDIATE CONCERNS INCLUDE FOG THIS MORNING AND INCOMING RAIN. SURFACE MAP EARLY THIS MORNING HAS A WEAK TROUGH EXTENDING N-S ACROSS MN/IA. WEAKLY CONVERGENT AND VERY DAMP LOWER BOUNDARY LAYER HAS LED TO SOME AREAS OF DENSE FOG ACROSS PORTIONS OF NORTHEAST IA/SOUTHEAST MN AND WEST CENTRAL WI. AS A RESULT...A DENSE FOG ADVISORY IS IN EFFECT UNTIL 10 AM. OTHERWISE...WATER VAPOR AND RAP 500MB ANALYSIS SHOWING A DEEPENING LONG WAVE BASICALLY ALONG THE SPINE OF THE ROCKY MOUNTAINS. AT THE SURFACE...CYCLOGENESIS WAS TAKING PLACE OVER THE TX/OK PANHANDLE. LIFT AHEAD OF THIS TROUGH AND SURFACE LOW WAS PRODUCING SCATTERED SHOWERS AN THUNDERSTORMS ACROSS THE PLAINS/MID-MISSISSIPPI RIVER VALLEY REGION. OVER THE LOCAL AR X FORECAST AREA...BESIDES THE FOG...SKIES WERE MOSTLY CLOUDY WITH TEMPERATURES IN THE 50S TO THE LOWER 60S. FOR TODAY...WILL BE WATCHING THE LOW OVER THE TX/OK PANHANDLE LIFT NORTHEAST IN MO BY NOON AND NORTHERN IL BY EARLY THIS EVENING. AS THIS OCCURS...850 MB MOISTURE TRANSPORT/850-500MB FRONTOGENESIS AND ISENTROPIC LIFT WILL ALL COMBINE FORCES TO SPREAD SHOWERS AND ISOLATED THUNDERSTORMS INTO THE AREA... BECOMING MORE WIDESPREAD IN THE AFTERNOON. OTHERWISE...EXPECT HIGHS TO TOP OFF IN THE MIDDLE 60S TO THE LOWER 70S. FOR TONIGHT...THE LOW WILL CONTINUE TO LIFT NORTHEAST ACROSS EASTERN WI. THIS PUTS ARX FORECAST AREA UNDER FAIRLY STRONG 850-500MB FRONTOGENETIC BAND IN THE 00-06Z TIME FRAME. THIS IS EXPECTED TO DRIVE WIDESPREAD MODERATE RAINFALL WITH AMOUNTS LIKELY RANGING FROM 1/4 TO 1/2 INCH. THEN AFTER MIDNIGHT...PLAN ON RAIN TAPERING OFF FROM WEST TO EAST AS THE LOW PULLS INTO EASTERN LAKE SUPERIOR. STRENGTHENING PRESSURE GRADIENT ACROSS THE AREA IN THE WAKE OF THE LOW WILL PRODUCE INCREASING NORTHWEST WINDS THROUGH THE OVERNIGHT HOURS. COLD AIR ADVECTION WILL DROP TEMPERATURES INTO THE MIDDLE 40S TO AROUND THE 50 DEGREE MARK. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 325 AM CDT THU OCT 2 2014 GUSTY NORTHWEST WINDS WILL OVERSPREAD THE AREA IN THE WAKE OF DEEPENING SURFACE LOW PULLING INTO EASTERN ONTARIO. PLAN ON SUSTAINED WIND SPEEDS IN THE 15 TO 25 MPH RANGE WITH GUSTS 25 TO 35 MPH. PV-ADVECTION ASSOCIATED WITH INCOMING MID-LEVEL LOW WILL ALSO PRODUCE A CHANCE OF SHOWERS MAINLY EAST OF THE MISSISSIPPI RIVER. COLDER TEMPERATURES/GUSTY NORTHWEST WINDS/RAIN SHOWERS WILL ALL COMBINE FOR A PRETTY RAW DAY. AS THE MID-LEVEL LOW ROTATES SOUTHEAST ACROSS THE AREA SATURDAY NIGHT...LOOKING FOR SCATTERED SHOWERS TO RESULT. AS TEMPERATURES COOL INTO THE MID/UPPER 30S LATER IN THE NIGHT...THERE IS THE POSSIBILITY OF A FEW SNOW FLAKES MIXING IN AT TIMES. RAIN SHOWERS WILL STILL BE POSSIBLE ON SATURDAY MAINLY EAST OF THE MISSISSIPPI RIVER IN COLD CYCLONIC FLOW. OTHERWISE...ANOTHER RAW AUTUMN DAY ON TAP AS HIGHS ONLY TOP OFF IN THE MIDDLE/UPPER 40S. CONTINUED COLD AIR ADVECTION SATURDAY NIGHT WILL DROP TEMPERATURES NEAR THE FREEZING MARK FOR A GOOD PART OF THE AREA. LONG WAVE TROUGH/CLOSED LOW WILL LINGER ACROSS THE REGION THROUGH MONDAY FOR BELOW NORMAL TEMPERATURES. AN EMBEDDED SHORTWAVE TROUGH LOOKS TO MAKE PASSAGE ACROSS THE AREA ON MONDAY FOR A CHANCE OF SHOWERS. OTHERWISE...PLAN ON HIGHS SUNDAY AND MONDAY IN THE MIDDLE 40S TO THE MIDDLE 50S WITH OVERNIGHT LOWS IN THE 30S. FOR TUESDAY AND WEDNESDAY...THE CLOSED LOW FILLS AND LIFTS NORTHEAST INTO CANADA WITH HEIGHTS BUILDING IN FROM THE WEST. THIS IS EXPECTED TO PRODUCE A SLOW MODERATION IN TEMPERATURES WITH HIGHS IN THE 50S/FEW LOWER 60S TUESDAY...AND IN THE 60S WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z FRIDAY AFTERNOON) ISSUED AT 1228 PM CDT THU OCT 2 2014 VLIFR/LIFR CONDITIONS STILL SIT AT RST AS DAYTIME HEATING HAS BEEN SLOW AT MIXING OUT THE FOG PRESENT THERE. ANTICIPATING SOME SLOW IMPROVEMENT TO BOTH CEILINGS AND VISIBILITIES THROUGH THE AFTERNOON AS DAYTIME HEATING CONTINUES TO WORK ON THE FOG AND STRATUS. SHOWERS MOVING IN LATER THIS AFTERNOON COULD HELP TO IMPROVE VISIBILITY SOME...THOUGH. AT LSE...VISIBILITIES ARE ALREADY VFR WITH CEILINGS FLIRTING WITH MVFR. ANTICIPATING CEILINGS THERE TO RISE FULLY TO MVFR BY 20Z...EVEN WITH SHOWERS MOVING IN. A FRONTAL PASSAGE LOOKS TO OCCUR AROUND 00Z...WHICH PRESSURES RISING IN ITS WAKE MAY ALLOW FOR A PERIOD OF NORTHWEST 20 KT GUSTS THIS EVENING. CEILINGS APPEAR TO HOLD STEADY THROUGH THE EVENING...THOUGH THERE COULD BE A RISE DUE TO THE NORTHWEST WIND. A BETTER SHOT FOR RISING CEILINGS COMES AFTER 06Z AS A WEDGE OF CLEARING OVER THE EASTERN DAKOTAS MOVES IN. HAVE TRIED TO TIME THAT CLEARING IN THE TAF...BUT MAY NEED SOME ADJUSTMENT IN LATER FORECASTS. ANOTHER COLD FRONTAL PASSAGE WILL MOVE THROUGH THE TAF SITES AROUND 12Z FRIDAY. A TIGHT PRESSURE GRADIENT IN ITS WAKE PLUS COLD AIR FLOWING IN SHOULD HELP KICK UP THE NORTHWEST WINDS TO 10 TO 20 KT...WITH GUSTS OF 25-30 KT BY MID-DAY. A PERIOD OF MVFR CEILINGS LOOKS LIKELY TOO IN THE WAKE OF THE FRONT...WITH DAYTIME MIXING INCREASING THE CEILING THROUGH THE MORNING. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ UPDATE...ZT SHORT TERM...DAS LONG TERM....DAS AVIATION...AJ