Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 11/28/14


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
305 PM MST WED NOV 26 2014 .SHORT TERM...(THIS AFTERNOON THROUGH THURSDAY) ISSUED AT 305 PM MST WED NOV 26 2014 AN UPPER LEVEL RIDGE OVER THE WESTERN STATES WILL FLATTEN AS IT SHIFTS EAST OVER THE GREAT BASIN THURSDAY. THIS WILL CAUSE THE NORTHWEST FLOW ALOFT OVER COLORADO TO BECOME WEST-NORTHWESTERLY TOMORROW. SOME CLOUDS ARE LINGERING OVER THE MOUNTAINS AND PERHAPS A FEW FLURRIES TOO. THERE IS ALSO A SLIGHT CHANCE FOR LIGHT SNOW OVER THE NORTHEAST PLAINS THIS EVENING. THE HRRR SHOWS A SMALL BAND REFORMING THIS EVENING. NOT SOLD ON THIS...SO WILL STICK TO THE SLIGHT CHANCE. IF ANY SNOW FORMS...IT SHOULD BE LIGHT. A SURFACE HIGH PRESSURE OVER THE EASTERN PLAINS AND A SURFACE TROUGH ALONG THE BASE OF THE FOOTHILLS HAS KEPT THE COOLER AIR OVER NORTHEAST COLORADO TODAY. THE LEE SIDE TROUGH ALONG WITH HIGHER PRESSURE OVER THE GREAT BASIN HAS PRODUCED WINDY CONDITIONS IN THE MOUNTAINS AND FOOTHILLS. TEMPERATURES HAVE WARMED NICELY IN THE LOWER FOOTHILLS WITH READINGS IN THE UPPER 40S. AS HIGH PRESSURE SHIFTS EAST OF THE REGION AND A SURFACE TROUGH DEEPENS OVER THE NORTHERN ROCKIES...SOUTH TO SOUTHWEST WINDS WILL FLUSH OUT THE COOLER AIR OVER NORTHEAST COLORADO AND LEAD TO MILD TEMPERATURES FOR THANKSGIVING. THERE WILL STILL BE SOME MOISTURE AT THE MID AND UPPER LEVELS...SO WAVE CLOUDS ARE EXPECTED AT TIMES. THIS MAY SLOW WARMING SOME...BUT STILL LOOKS LIKE HIGHS WILL CLIMB ABOVE 60 DEGREES ACROSS NORTHEAST COLORADO. WINDS WILL BE GUSTY IN THE FOOTHILLS AND MOUNTAINS AGAIN WITH GUSTS TO 50 TO 60 MPH IN THE WIND PRONE AREAS OF THE MOUNTAINS AND FOOTHILLS. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 305 PM MST WED NOV 26 2014 ...A DRY AND WARM PATTERN IS SETTING UP FOR FRIDAY THROUGH SUNDAY... STARTING WITH FRIDAY A DRY AIRMASS WILL BE IN PLACE WITH STRONG WNW FLOW ALOFT. ACCORDING TO MODEL CROSS-SECTIONS A MOUNTAIN WAVE WILL FORM THURSDAY EVENING INTO EARLY FRIDAY. SUSTAINED WINDS OF 40 TO 45 MPH WITH GUSTS UP TO 70 WILL BE POSSIBLE OVER THE HIGHER MOUNTAIN PEAKS. THERE IS A LACK OF AN INVERSION LAYER AT MOUNTAIN TOP SO IT WILL DIFFICULT TO BRING THOSE WINDS DOWN TO THE SURFACE SO HIGHER WINDS SHOULD REMAIN WITHIN THE MOUNTAINS. HOWEVER...CHINOOK WARMING WILL OCCUR ON FRIDAY AND AID IN GETTING AREAS CLOSE TO THE FOOTHILLS WELL ABOVE SEASONAL NORMALS. CURRENT TRENDS HAVE HIGHS IN THE LOWER 70S FOR THE DENVER METRO. THIS WOULD EITHER MEET OR EXCEED THE CURRENT RECORD HIGH FOR FRIDAY OF 72 SET BACK IN 1901. DRY PATTERN CONTINUES INTO SATURDAY AND EARLY SUNDAY WITH WESTERLY FLOW BECOMING MORE DOMINANT. WINDS OVER THE MOUNTAINS WILL CONTINUE WITH GUSTING TO 70 MPH STILL POSSIBLE OVER MOUNTAIN TOP. MOUNTAIN TOP STABILITY IS STILL LACKING SO WILL KEEP WINDS ISOLATED TO THE MOUNTAINS FOR THE TIME BEING. TEMPERATURES WILL CONTINUE TO BE WELL ABOVE SEASONAL NORMALS WITH HIGHS ON SATURDAY IN THE UPPER 60S. FOR SUNDAY...MODELS STILL INDICATING A STRONG MOUNTAIN WAVE IN THE MORNING WITH WINDS CONTINUING TO GUST TO 60-65 OVER MOUNTAIN PEAKS. THE MAIN FEATURE HOWEVER FOR THIS TIMEFRAME IS AN ELONGATED UPPER LEVEL TROF MOVING THROUGH THE REGION BRINGING A BACKDOOR COLD FRONT INTO THE EASTERN PORTIONS OF THE STATE. THIS WILL BRING HIGH TEMPERATURES DOWN SIGNIFICANTLY WITH THE PLAINS STRUGGLING TO GET OUT OF THE 40S. MOISTURE STILL LACKING WITH THIS SYSTEM SO LEFT POPS OUT. FOR MONDAY AND TUESDAY...MODELS ARE STILL IN DISAGREEMENT WITH THE TIMING OF THE SYNOPTIC FEATURES FOR THE NEXT SYSTEM. THE GFS SHOWS WESTERLY FLOW WITH INCREASING MOISTURE AHEAD OF THE FRONT WITH LITTLE PRECIP ASSOCIATED...WHILE THE EC HAS A MORE NORTHWEST FLOW WITH RAIN MOVING INTO THE WESTERN PORTIONS OF THE STATE BY MONDAY MORNING. WILL KEEP CURRENT POPS WITH NO CHANGES FOR THIS PERIOD. && .AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING) ISSUED AT 305 PM MST WED NOV 26 2014 VFR CONDITIONS WILL PREVAIL THE NEXT 24 HOURS WITH MID AND HIGH CLOUDS AT TIMES. NORTHEAST WINDS ARE EXPECTED TO TURN SOUTHEASTERLY JUST AFTER 00Z AT KDEN AND THEN BECOME SOUTHERLY BY 03Z. SOUTH TO SOUTHWEST WINDS ARE THEN EXPECTED TO PREVAIL THE REST OF TONIGHT AND THURSDAY THROUGH OUT THE DENVER AREA. WIND SPEEDS SHOULD REMAIN LESS THAN 20 KNOTS TONIGHT AND THURSDAY. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...MEIER LONG TERM...BOWEN AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
923 AM MST WED NOV 26 2014 .UPDATE... ISSUED AT 923 AM MST WED NOV 26 2014 RADAR SHOWING A BAND SNOW STILL HANGING ON OVER THE NORTHEAST CORNER OF THE STATE. RAISED POPS FOR THIS THROUGH THE MORNING WHERE UP TO AN ADDITIONAL INCH OF SNOW WILL BE POSSIBLE. INCREASED WINDS ALONG HIGHWAY 285 ACROSS PARK COUNTY FOR TODAY. OBSERVATIONS SHOWING GUSTS T0 60 MPH HERE...THE RAP AND HRRR SHOW THESE STRONG WINDS CONTINUING THROUGH MID AFTERNOON. INCREASED THE FORECAST TO INDICATE GUSTS TO 70 MPH WILL BE POSSIBLE. PLAN ON LETTING THE WINTER WEATHER ADVISORY EXPIRE AT NOON. WEB CAMERAS JUST SHOWING LIGHT SNOW IN PLACES. IN GENERAL...CONDITIONS ARE STARTING IMPROVE IN THE HIGH COUNTRY...THOUGH MANY ROADS ARE STILL SNOW COVERED. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 222 AM MST WED NOV 26 2014 NW FLOW ALOFT WILL CONTINUE OVER THE AREA TODAY. CROSS-SECTIONS STILL SHOW ENOUGH MOISTURE IN THE MTNS COMBINED WITH MARGINAL LAPSES WHICH WILL LEAD TO ADDITIONAL SNOWFALL THRU THE MORNING HOURS BEFORE DIMINISHING IN THE AFTN AS DRIER AIR BEGINS TO ADVECT IN. MEANWHILE GUSTY NW WINDS WILL CONTINUE AS WELL SO EXPECT BLOWING SNOW MAINLY ABOVE 10000 FT THUS WILL EXTEND ADVISORY THRU NOON. AT LOWER ELEVATIONS NERN CO REMAINS ON THE BACKSIDE OF AN UPPER LEVEL JET WHICH WILL ALLOW FOR SOME ADDITIONAL BANDED PCPN THRU THE MORNING HOURS ACROSS THE PLAINS. MOST OF THE ACTIVITY WILL FOCUS ENE OF A GREELEY TO LIMON LINE. WEAK UPSLOPE ALONG THE FRONT RANGE MAY LEAD TO SOME VERY LIGHT SNOW/FLURRIES AS WELL THRU MID MORNING. BY MIDDAY SHOULD PCPN CHANCES END OVER THE PLAINS. AS FOR HIGHS THERE COULD BE QUITE A RANGE OVER NERN CO WITH READINGS IN THE LOWER 50S AROUND DENVER WHILE FURTHER NE OVER THE PLAINS HIGHS STAY IN THE 30S. FOR TONIGHT OUTSIDE OF A FEW -SHSN IN THE MTNS THIS EVENING IT SHOULD BE DRY. A MTN WAVE WILL DEVELOP OVERNIGHT WITH CROSS-MTN FLOW IN THE 40-45 KT RANGE. THUS WILL SEE GUSTY WINDS IN THE HIGHER MTNS AND FOOTHILL AREAS BUT SPEEDS SHOULD STAY BLO HIGH WIND CRITERIA. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 222 AM MST WED NOV 26 2014 A DRYING AND WARMING TREND WILL BE THE MAIN FEATURES FROM THURSDAY THROUGH SATURDAY AS TEMPERATURES CLIMB ABOVE NORMAL FOR THIS TIME OF YEAR. FOR THURSDAY...A DRYING AIRMASS WILL BE IN PLACE AS THE FLOW ALOFT REMAINS FROM THE NORTHWEST WITH DOWNSLOPE FLOW. CROSS SECTIONS SHOW STRONG WEST TO NORTHWEST FLOW INCREASING AT MOUNTAIN TOP THROUGH THE DAY BUT WITH LACK OF MOUNTAIN TOP STABILITY EXPECT MUCH OF THE HIGHER WINDS TO BE CONFINED TO THE MOUNTAINS PASSES AND HIGHER EAST SLOPES WITH GUSTS UP TO 70 MPH POSSIBLE. FOR FRIDAY AND SATURDAY...THE FLOW ALOFT BECOMES MORE WESTERLY UNDER A VERY DRY AIRMASS. THERE WILL BE CONTINUED GUSTY WINDS OVER THE MOUNTAINS AND HIGHER EAST SLOPES WITH GUSTS UP TO 70 MPH BUT AGAIN HIGHER WINDS WILL BE MORE CONFINED TO HIGHER AREAS. TEMPERATURES WILL CONTINUE TO WARM OVER LOWER ELEVATIONS WITH READINGS FLIRTING INTO THE UPPER 60S AND LOWER 70S AND POSSIBLE RECORD HIGHS IF WE GET ENOUGH LOW LEVEL MIXING AND DOWNSLOPE FLOW. SIMILAR CONDITIONS EXPECTED FOR SATURDAY UNDER STRONG WESTERLY FLOW ALOFT AND CONTINUED ABOVE NORMAL TEMPERATURES FOR THIS TIME OF YEAR. FOR SUNDAY...AN UPPER TROF SWEEPS ACROSS THE NORTHERN HIGH PLAINS WHICH SENDS AN ASSOCIATED COLD FRONT INTO NORTHEAST COLORADO LATE IN THE DAY. THE RESULT WILL BE COOLER TEMPERATURES BUT STILL LOOKS TOO DRY FOR ANY PRECIP. BY LATE MONDAY AND TUESDAY...LONG RANGE MODELS ARE IN CONSIDERABLE DISAGREEMENT WITH THE LARGE SCALE FEATURES. THE GFS SHOWS INCREASING MOISTURE AHEAD OF A PACIFIC DISTURBANCE. ON THE OTHER HAND THE EUROPEAN HAS A NORTHWEST FLOW PATTERN WITH SOME EMBEDDED SHOWERS. FOR NOW WILL MAINTAIN JUST A SLIGHT CHANCE OF SNOW SHOWERS IN THE MOUNTAINS ON TUESDAY. && .AVIATION...(FOR THE TAFS THROUGH 18Z THURSDAY MORNING) ISSUED AT 923 AM MST WED NOV 26 2014 SNOW WILL COME TO AN END TODAY OVER THE MOUNTAINS AND NORTHEAST PLAINS...WHILE THE DENVER AREA IS EXPECTED TO REMAIN SNOW FREE TODAY. THE LOW CLOUDS WILL CONTINUE TO BURN OFF IN THE DENVER AREA...AND EXPECTED VFR CONDITIONS THROUGH OUT THE DENVER AREA BY 18Z. WINDS WILL REMAIN ON THE LIGHT SIDE...TODAY AND TONIGHT. WIND DIRECTION WILL BE EASTERLY TODAY AND THEN TURN SOUTHERLY AFTER 00Z. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL NOON MST TODAY FOR COZ031-033-034. && $$ UPDATE...MEIER SHORT TERM...RPK LONG TERM...ENTREKIN AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS ALBANY NY
115 AM EST WED NOV 26 2014 .SYNOPSIS... A COASTAL LOW WILL BRING A WIDESPREAD SNOWFALL TO THE AREA THAT WILL SIGNIFICANTLY IMPACT HOLIDAY TRAVEL WEDNESDAY AND WEDNESDAY NIGHT. HEAVY SNOWFALL IS EXPECTED ACROSS WESTERN NEW ENGLAND AND MUCH OF EASTERN NEW YORK WITH THE HEAVIEST SNOW OCCURRING THE AFTERNOON INTO THE EVENING. THE SNOW IS EXPECTED TO TAPER LATE WEDNESDAY NIGHT...WITH SOME LINGERING SNOW SHOWERS ACROSS THE AREA FOR THANKSGIVING DAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 1 AM EST...COLDER AIR CONTINUES TO FILTER IN...HELPING TO SET THE STAGE FOR A WIDESPREAD SNOWFALL. SATELLITE IMAGERY SHOWING MID AND HIGH CLOUDS BUILDING NORTH AND NORTHEAST FROM THE SOUTHEASTERN U.S. AND STRATOCUMULUS EDGING EAST FROM THE GREAT LAKES. HIGH AND MID LEVEL CLOUDS HAVE OVERSPREAD MUCH OF THE REGION...OUTSIDE OF A FEW OCCASIONAL THIN SPOTS. SOME MINOR ADJUSTMENTS TO TEMPERATURES THROUGH DAYBREAK. WILL BE TRACKING THE NORTHWESTERN EDGE OF THE UPPER DEFORMATION ZONE DEVELOPING IN THE SOUTHEASTERN U.S. TO GET A FEEL FOR THE NORTHWESTERN EXTENT OF THE HEAVIEST SNOW AS THE UPPER DEFORMATION TRACKS TOWARD THE NORTHEASTERN U.S. INTERESTING WATER VAPOR IMAGERY SHOWS 2 CLOSED UPPER VORTICITY CENTERS LINED UP FROM JUST NORTH OF THE GREAT LAKES THROUGH EASTERN CANADA...SO WILL THE EXTENSIVE LINE OF SHEAR ASSOCIATED WITH STRONG UPPER JET ENERGY ALONG THE EASTERN U.S. HELP THE UPPER DEFORMATION IN THE UPCOMING STORM TO BECOME A CLOSED VORTICITY CENTER LIKE THE ONES DOWNSTREAM? IF SO...PERHAPS THE UPCOMING STORM COULD HAVE MORE UPPER DYNAMICS AND BUILD THE HEAVIER PRECIPITATION FURTHER NORTH. THAT WOULD BE A BIT DIFFERENT THAN THE OPEN WAVE ALL THE GUIDANCE SUGGESTS ASSOCIATED WITH THE UPCOMING STORM...BUT JUST HAVE TO WATCH TRENDS TO REFINE THE FORECAST THROUGH THE NIGHT. LOWS IN THE 20S NORTH TO LOWER TO MID 30S CENTRAL AND SOUTH. BASED ON THE LATEST RADAR AND SATELLITE TRENDS AND LATEST HRRR AND LOCAL WRF...THE ONSET OF THE SNOW COULD BE MORE AROUND SUNRISE RATHER THAN BEFORE SUNRISE IN SOUTHERN AND CENTRAL AREAS. CLOUDS WILL ALSO THICKEN AND LOWER TONIGHT. SO...LIGHT PRECIPITATION SHOULD BEGIN TO MOVE INTO THE CENTRAL AND SOUTHEASTERN CATSKILLS...MID HUDSON VALLEY...LITCHFIELD COUNTY AND SOUTHERN BERKSHIRES AROUND SUNRISE WITH SOME MIXED POSSIBLE OF SNOW...RAIN AND SLEET TO START. SOME MINOR ADJUSTMENTS TO THE FORECASTED ONSET LATER TONIGHT AND TOMORROW MORNING. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... WINTER STORM WARNINGS AND WINTER WEATHER ADVISORIES REMAIN IN EFFECT. THE HIGHEST SNOWFALL AMOUNTS ARE EXPECTED ACROSS THE WESTERN NEW ENGLAND...THE TACONICS...THE HIGHER TERRAIN OF THE CENTRAL AND SOUTHEASTERN CATSKILLS AND PORTIONS OF THE MID HUDSON VALLEY. AMOUNTS WILL DECREASE AS YOU HEAD NORTHWEST ACROSS THE FORECAST AREA AWAY FROM THE COASTAL LOW WITH THE GRADIENT BETWEEN WARNING LEVEL AND ADVISORY LEVEL SNOWFALL EXPECTED TO OCCUR IN THE VICINITY OF THE SCHOHARIE VALLEY...CAPITAL DISTRICT AND LAKE GEORGE SARATOGA AREA. THIS IS WHY THE WINTER STORM WATCH WAS IN EFFECT AS LONG AS IT WAS. MILLER TYPE A COASTAL LOW TAPPING GULF MOISTURE. SOUTHERN STREAM ENERGY IS INITIATING THE DEVELOPING OF A LOW ALONG THE GULF COASTAL ALONG A STALLED FRONTAL BOUNDARY. THE LOW WILL TRACK NORTHEASTWARD AND DEEPEN. THE GUIDANCE HAS COME INTO GOOD AGREEMENT ON THE TRACK...POSITION AND STRENGTH OF THE STORM PASSING THE LOW JUST SOUTH OF CAPE COD WEDNESDAY EVENING. THE DIFFERENCES ARE OCCURRING IN THE QPF. GUIDANCE ALSO CONTINUES TO INDICATE BANDING WILL OCCUR ESPECIALLY FOR AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT HENCE THE HIGHER SNOWFALL FORECAST. SNOWFALL RATES OF UP TO AN INCH AN HOUR ARE EXPECTED EXPECTED AT TIMES ACROSS PORTIONS OF THE WARNING AREA WITH AROUND 2 INCHES AN HOUR POSSIBLE SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE BANDING IS MORE LIKELY. SNOW RATIO WILL BE LOWER ACROSS THE MID HUDSON AND NORTHWESTERN CONNECTICUT AND WITH THE HIGHER TOTALS AND STRONGER WINDS SOME ISOLATED POWER OUTAGES CAN BE RULED OUT. APPROACHING NORTHERN STREAM ENERGY DOES NOT PHASE WITH THE SOUTHERN STREAM KEEPING STORM PROGRESSIVE BUT WILL BRING CHANCES FOR SNOW SHOWERS TO THE REGION FOR THANKSGIVING DAY AND NIGHT ESPECIALLY ACROSS THE HIGHER TERRAIN. LITTLE RECOVERY IN TEMPERATURES WEDNESDAY UPPER 20S TO MID 30S. MUCH COLDER AIR WILL NOT BE DRAWN INTO THE REGION UNDER AFTER THE NORTHERN STREAM ENERGY MOVES OFF TO THE EAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... THE LONG TERM PERIOD WILL BE CHARACTERIZED BY PERIODS OF UNSETTLED WEATHER...AS A SERIES OF FAST-MOVING SYSTEMS IMPACT THE REGION. AT THE START OF THE LONG TERM PERIOD...IN THE WAKE OF THE COASTAL STORM THAT IMPACTED THE REGION IN THE SHORT TERM PERIOD...THE FORECAST AREA WILL BE UNDERNEATH A NORTHWEST FLOW REGIME THAT WILL GRADUALLY BE DEAMPLIFYING HEADING INTO THE WEEKEND. BY THE WEEKEND...THE FLOW WILL BECOME QUASI-ZONAL...ALLOWING FOR FAST PIECES OF NORTHERN STREAM ENERGY TO MOVE THROUGH IT...IN WHICH THE TIMING AND IMPACTS OF THESE FEATURES COULD CHANGE OVER THE NEXT FEW DAYS AS MEDIUM-RANGE GUIDANCE OFTEN STRUGGLES HANDLING FAST ZONAL FLOW. THE FIRST OF THESE PIECES OF ENERGY WILL AFFECT MAINLY AREAS NORTH AND WEST OF THE CAPITAL REGION THURSDAY NIGHT...AS AN UPPER-LEVEL SHORTWAVE RACES THROUGH THE NORTHWEST FLOW PROVIDING A PERIOD OF SCATTERED LIGHT SNOW SHOWERS. ACCUMULATIONS WITH THIS FEATURE WILL BE LIGHT...ON THE ORDER OF AN INCH OR TWO ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS...AND A DUSTING TO PERHAPS AN INCH ACROSS PORTIONS OF THE MOHAWK VALLEY AND LAKE GEORGE/SARATOGA REGION. MUCH OF THE REGION LOOKS TO BE DRY DURING THE DAY FRIDAY...EXCEPT FOR SOME SCATTERED LAKE EFFECT SNOW SHOWERS THAT MAY SKIRT PORTIONS OF HERKIMER COUNTY DOWNWIND OF LAKE ONTARIO. THE NEXT SYSTEM LOOKS TO IMPACT THE REGION FOR MUCH OF THE WEEKEND AS AN AREA OF LOW PRESSURE TRACKS NORTHEAST FROM THE CENTRAL PLAINS TO THE GREAT LAKES. OUT AHEAD OF THIS LOW PRESSURE SYSTEM...WARM AIR ADVECTION PRECIP AHEAD OF AN APPROACHING WARM FRONT MAY ALLOW FOR SCATTERED RAIN/SNOW SHOWERS SATURDAY INTO SATURDAY NIGHT. NOT MUCH MOISTURE/DYNAMICS WILL BE PRESENT WITH THIS BOUNDARY AS THE LOW PRESSURE CENTER WILL BE LIFTING FAR NORTH AND WEST OF THE REGION. DURING THE DAY SUNDAY...THE WARM FRONT SHOULD LIFT NORTH ACROSS THE REGION...USHERING IN ANOTHER SHORT PERIOD OF MILD WEATHER WITH SCATTERED RAIN/SNOW SHOWERS. HIGH PRESSURE LOOKS TO BUILD ACROSS THE REGION FOR THE START OF NEXT WEEK RESULTING IN A PERIOD OF DRY WEATHER INTO THE MIDDLE OF NEXT WEEK. HIGH TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL GENERALLY RANGE FROM THE UPPER 20S TO UPPER 30S...EXCEPT ON SUNDAY WHERE HIGHS WILL RANGE FROM THE UPPER 30S TO NEAR 50 IN VALLEY AREAS AND LOW 30S TO MID 40S MONDAY. LOW TEMPERATURES WILL GENERALLY RANGE FROM THE MID TEENS TO LOW 20S EXCEPT FOR UPPER 20S TO MID 30S SATURDAY AND SUNDAY NIGHTS. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... A DEVELOPING NOR`EASTER WILL BRING A WIDESPREAD SNOWFALL TO THE AREA THAT WILL SIGNIFICANTLY IMPACT HOLIDAY TRAVEL TODAY INTO TONIGHT. PRIOR TO SNOW ARRIVING...VFR CONDITIONS EXPECTED TO PREVAIL THROUGH 12Z AT MOST OF THE TERMINALS. KPOU COULD SEE LIGHT SNOW AND IFR VSBY DEVELOPING JUST BEFORE 12Z...SO HAVE INCLUDED A TEMPO TO MENTION THIS STARTING AT 11Z. OTHERWISE CONDITIONS WILL QUICKLY DETERIORATE TO IFR AS SNOW SPREADS FROM SOUTH TO NORTH BETWEEN 12Z-15Z. SNOW WILL INCREASE IN INTENSITY BY EARLY TO MID AFTERNOON...WITH CONDITIONS LIKELY DETERIORATING TO LIFR. SNOW WILL START TO LIGHTEN IN INTENSITY AFTER 00Z THURSDAY...WITH LIGHT SNOW PERSISTING THROUGH 06Z THURSDAY WITH CONTINUED IFR CONDITIONS. WINDS WILL BECOME NORTHERLY AROUND 5-10 KTS BY LATER THIS MORNING...SHIFTING TO THE NORTHWEST THIS EVENING. OUTLOOK... WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN. THANKSGIVING DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. THURSDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE WEEKEND. WIDESPREAD SNOWFALL AS COASTAL LOW IMPACTS REGION WEDNESDAY AND WEDNESDAY NIGHT. WARMER TEMPERATURES SUNDAY WILL BE SHORT LIVED AND WILL RESULT SOME SNOW MELT AND RIPENING OF SNOW PACK. HOWEVER TEMPERATURES ARE EXPECTED TO BE IN THE MID 30S AND COLDER SATURDAY NIGHT AND SUNDAY NIGHT SO MELT IS STOP. 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...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR CTZ001-013. NY...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR NYZ058>061-063>066. WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST THURSDAY FOR NYZ047>054-084. WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 7 AM EST THURSDAY FOR NYZ032-033-038>043-082-083. MA...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR MAZ001-025. VT...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR VTZ013>015. && $$ SYNOPSIS...IAA NEAR TERM...IAA/KL/NAS SHORT TERM...IAA LONG TERM...IRL AVIATION...JPV HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS ALBANY NY
1254 AM EST WED NOV 26 2014 .SYNOPSIS... A COASTAL LOW WILL BRING A WIDESPREAD SNOWFALL TO THE AREA THAT WILL SIGNIFICANTLY IMPACT HOLIDAY TRAVEL WEDNESDAY AND WEDNESDAY NIGHT. HEAVY SNOWFALL IS EXPECTED ACROSS WESTERN NEW ENGLAND AND MUCH OF EASTERN NEW YORK WITH THE HEAVIEST SNOW OCCURRING THE AFTERNOON INTO THE EVENING. THE SNOW IS EXPECTED TO TAPER LATE WEDNESDAY NIGHT...WITH SOME LINGERING SNOW SHOWERS ACROSS THE AREA FOR THANKSGIVING DAY. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... COLDER AIR FILTERS IN HELPING TO SET THE STAGE FOR A WIDESPREAD SNOWFALL. SATELLITE IMAGERY SHOWING MID AND HIGH CLOUDS BUILDING NORTH AND NORTHEAST FROM THE SOUTHEASTERN U.S. AND STRATOCUMULUS EDGING EAST FROM THE GREAT LAKES. MOST AREAS SHOULD BE CLOUDY BEFORE MIDNIGHT...WHICH COULD LIMIT THE COOLING ACROSS THE REGION. ALTHOUGH...STILL SOME COLD ADVECTION OCCURRING AS WEST LOW LEVEL WIND FLOW AND COOLING BOUNDARY LAYER TEMPERATURES SPREAD ACROSS THE REGION THROUGH THE NIGHT. SOME MINOR ADJUSTMENTS TO TEMPERATURES THROUGH TONIGHT. WILL BE TRACKING THE NORTHWESTERN EDGE OF THE UPPER DEFORMATION ZONE DEVELOPING IN THE SOUTHEASTERN U.S. TO GET A FEEL FOR THE NORTHWESTERN EXTENT OF THE HEAVIEST SNOW AS THE UPPER DEFORMATION TRACKS TOWARD THE NORTHEASTERN U.S. INTERESTING WATER VAPOR IMAGERY SHOWS 2 CLOSED UPPER VORTICITY CENTERS LINED UP FROM JUST NORTH OF THE GREAT LAKES THROUGH EASTERN CANADA...SO WILL THE EXTENSIVE LINE OF SHEAR ASSOCIATED WITH STRONG UPPER JET ENERGY ALONG THE EASTERN U.S. HELP THE UPPER DEFORMATION IN THE UPCOMING STORM TO BECOME A CLOSED VORTICITY CENTER LIKE THE ONES DOWNSTREAM? IF SO...PERHAPS THE UPCOMING STORM COULD HAVE MORE UPPER DYNAMICS AND BUILD THE HEAVIER PRECIPITATION FURTHER NORTH. THAT WOULD BE A BIT DIFFERENT THAN THE OPEN WAVE ALL THE GUIDANCE SUGGESTS ASSOCIATED WITH THE UPCOMING STORM...BUT JUST HAVE TO WATCH TRENDS TO REFINE THE FORECAST THROUGH THE NIGHT. LOWS IN THE 20S NORTH TO LOWER TO MID 30S CENTRAL AND SOUTH. BASED ON THE LATEST RADAR AND SATELLITE TRENDS AND LATEST HRRR AND LOCAL WRF...THE ONSET OF THE SNOW COULD BE MORE AROUND SUNRISE RATHER THAN BEFORE SUNRISE IN SOUTHERN AND CENTRAL AREAS. CLOUDS WILL ALSO THICKEN AND LOWER TONIGHT. SO...LIGHT PRECIPITATION SHOULD BEGIN TO MOVE INTO THE CENTRAL AND SOUTHEASTERN CATSKILLS...MID HUDSON VALLEY...LITCHFIELD COUNTY AND SOUTHERN BERKSHIRES AROUND SUNRISE WITH SOME MIXED POSSIBLE OF SNOW...RAIN AND SLEET TO START. SOME MINOR ADJUSTMENTS TO THE FORECASTED ONSET LATER TONIGHT AND TOMORROW MORNING. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... WINTER STORM WARNINGS AND WINTER WEATHER ADVISORIES REMAIN IN EFFECT. THE HIGHEST SNOWFALL AMOUNTS ARE EXPECTED ACROSS THE WESTERN NEW ENGLAND...THE TACONICS...THE HIGHER TERRAIN OF THE CENTRAL AND SOUTHEASTERN CATSKILLS AND PORTIONS OF THE MID HUDSON VALLEY. AMOUNTS WILL DECREASE AS YOU HEAD NORTHWEST ACROSS THE FORECAST AREA AWAY FROM THE COASTAL LOW WITH THE GRADIENT BETWEEN WARNING LEVEL AND ADVISORY LEVEL SNOWFALL EXPECTED TO OCCUR IN THE VICINITY OF THE SCHOHARIE VALLEY...CAPITAL DISTRICT AND LAKE GEORGE SARATOGA AREA. THIS IS WHY THE WINTER STORM WATCH WAS IN EFFECT AS LONG AS IT WAS. MILLER TYPE A COASTAL LOW TAPPING GULF MOISTURE. SOUTHERN STREAM ENERGY IS INITIATING THE DEVELOPING OF A LOW ALONG THE GULF COASTAL ALONG A STALLED FRONTAL BOUNDARY. THE LOW WILL TRACK NORTHEASTWARD AND DEEPEN. THE GUIDANCE HAS COME INTO GOOD AGREEMENT ON THE TRACK...POSITION AND STRENGTH OF THE STORM PASSING THE LOW JUST SOUTH OF CAPE COD WEDNESDAY EVENING. THE DIFFERENCES ARE OCCURRING IN THE QPF. GUIDANCE ALSO CONTINUES TO INDICATE BANDING WILL OCCUR ESPECIALLY FOR AREAS TO THE SOUTH AND EAST OF THE CAPITAL DISTRICT HENCE THE HIGHER SNOWFALL FORECAST. SNOWFALL RATES OF UP TO AN INCH AN HOUR ARE EXPECTED EXPECTED AT TIMES ACROSS PORTIONS OF THE WARNING AREA WITH AROUND 2 INCHES AN HOUR POSSIBLE SOUTH AND EAST OF THE CAPITAL DISTRICT WHERE BANDING IS MORE LIKELY. SNOW RATIO WILL BE LOWER ACROSS THE MID HUDSON AND NORTHWESTERN CONNECTICUT AND WITH THE HIGHER TOTALS AND STRONGER WINDS SOME ISOLATED POWER OUTAGES CAN BE RULED OUT. APPROACHING NORTHERN STREAM ENERGY DOES NOT PHASE WITH THE SOUTHERN STREAM KEEPING STORM PROGRESSIVE BUT WILL BRING CHANCES FOR SNOW SHOWERS TO THE REGION FOR THANKSGIVING DAY AND NIGHT ESPECIALLY ACROSS THE HIGHER TERRAIN. LITTLE RECOVERY IN TEMPERATURES WEDNESDAY UPPER 20S TO MID 30S. MUCH COLDER AIR WILL NOT BE DRAWN INTO THE REGION UNDER AFTER THE NORTHERN STREAM ENERGY MOVES OFF TO THE EAST. && .LONG TERM /FRIDAY THROUGH TUESDAY/... THE LONG TERM PERIOD WILL BE CHARACTERIZED BY PERIODS OF UNSETTLED WEATHER...AS A SERIES OF FAST-MOVING SYSTEMS IMPACT THE REGION. AT THE START OF THE LONG TERM PERIOD...IN THE WAKE OF THE COASTAL STORM THAT IMPACTED THE REGION IN THE SHORT TERM PERIOD...THE FORECAST AREA WILL BE UNDERNEATH A NORTHWEST FLOW REGIME THAT WILL GRADUALLY BE DEAMPLIFYING HEADING INTO THE WEEKEND. BY THE WEEKEND...THE FLOW WILL BECOME QUASI-ZONAL...ALLOWING FOR FAST PIECES OF NORTHERN STREAM ENERGY TO MOVE THROUGH IT...IN WHICH THE TIMING AND IMPACTS OF THESE FEATURES COULD CHANGE OVER THE NEXT FEW DAYS AS MEDIUM-RANGE GUIDANCE OFTEN STRUGGLES HANDLING FAST ZONAL FLOW. THE FIRST OF THESE PIECES OF ENERGY WILL AFFECT MAINLY AREAS NORTH AND WEST OF THE CAPITAL REGION THURSDAY NIGHT...AS AN UPPER-LEVEL SHORTWAVE RACES THROUGH THE NORTHWEST FLOW PROVIDING A PERIOD OF SCATTERED LIGHT SNOW SHOWERS. ACCUMULATIONS WITH THIS FEATURE WILL BE LIGHT...ON THE ORDER OF AN INCH OR TWO ACROSS PORTIONS OF THE SOUTHERN ADIRONDACKS...AND A DUSTING TO PERHAPS AN INCH ACROSS PORTIONS OF THE MOHAWK VALLEY AND LAKE GEORGE/SARATOGA REGION. MUCH OF THE REGION LOOKS TO BE DRY DURING THE DAY FRIDAY...EXCEPT FOR SOME SCATTERED LAKE EFFECT SNOW SHOWERS THAT MAY SKIRT PORTIONS OF HERKIMER COUNTY DOWNWIND OF LAKE ONTARIO. THE NEXT SYSTEM LOOKS TO IMPACT THE REGION FOR MUCH OF THE WEEKEND AS AN AREA OF LOW PRESSURE TRACKS NORTHEAST FROM THE CENTRAL PLAINS TO THE GREAT LAKES. OUT AHEAD OF THIS LOW PRESSURE SYSTEM...WARM AIR ADVECTION PRECIP AHEAD OF AN APPROACHING WARM FRONT MAY ALLOW FOR SCATTERED RAIN/SNOW SHOWERS SATURDAY INTO SATURDAY NIGHT. NOT MUCH MOISTURE/DYNAMICS WILL BE PRESENT WITH THIS BOUNDARY AS THE LOW PRESSURE CENTER WILL BE LIFTING FAR NORTH AND WEST OF THE REGION. DURING THE DAY SUNDAY...THE WARM FRONT SHOULD LIFT NORTH ACROSS THE REGION...USHERING IN ANOTHER SHORT PERIOD OF MILD WEATHER WITH SCATTERED RAIN/SNOW SHOWERS. HIGH PRESSURE LOOKS TO BUILD ACROSS THE REGION FOR THE START OF NEXT WEEK RESULTING IN A PERIOD OF DRY WEATHER INTO THE MIDDLE OF NEXT WEEK. HIGH TEMPERATURES THROUGHOUT THE LONG TERM PERIOD WILL GENERALLY RANGE FROM THE UPPER 20S TO UPPER 30S...EXCEPT ON SUNDAY WHERE HIGHS WILL RANGE FROM THE UPPER 30S TO NEAR 50 IN VALLEY AREAS AND LOW 30S TO MID 40S MONDAY. LOW TEMPERATURES WILL GENERALLY RANGE FROM THE MID TEENS TO LOW 20S EXCEPT FOR UPPER 20S TO MID 30S SATURDAY AND SUNDAY NIGHTS. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... A DEVELOPING NOR`EASTER WILL BRING A WIDESPREAD SNOWFALL TO THE AREA THAT WILL SIGNIFICANTLY IMPACT HOLIDAY TRAVEL TODAY INTO TONIGHT. PRIOR TO SNOW ARRIVING...VFR CONDITIONS EXPECTED TO PREVAIL THROUGH 12Z AT MOST OF THE TERMINALS. KPOU COULD SEE LIGHT SNOW AND IFR VSBY DEVELOPING JUST BEFORE 12Z...SO HAVE INCLUDED A TEMPO TO MENTION THIS STARTING AT 11Z. OTHERWISE CONDITIONS WILL QUICKLY DETERIORATE TO IFR AS SNOW SPREADS FROM SOUTH TO NORTH BETWEEN 12Z-15Z. SNOW WILL INCREASE IN INTENSITY BY EARLY TO MID AFTERNOON...WITH CONDITIONS LIKELY DETERIORATING TO LIFR. SNOW WILL START TO LIGHTEN IN INTENSITY AFTER 00Z THURSDAY...WITH LIGHT SNOW PERSISTING THROUGH 06Z THURSDAY WITH CONTINUED IFR CONDITIONS. WINDS WILL BECOME NORTHERLY AROUND 5-10 KTS BY LATER THIS MORNING...SHIFTING TO THE NORTHWEST THIS EVENING. OUTLOOK... WEDNESDAY NIGHT: HIGH OPERATIONAL IMPACT. DEFINITE SN. THANKSGIVING DAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. THURSDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. FRIDAY: NO OPERATIONAL IMPACT. NO SIG WX. FRIDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. SATURDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THROUGH THE WEEKEND. WIDESPREAD SNOWFALL AS COASTAL LOW IMPACTS REGION WEDNESDAY AND WEDNESDAY NIGHT. WARMER TEMPERATURES SUNDAY WILL BE SHORT LIVED AND WILL RESULT SOME SNOW MELT AND RIPENING OF SNOW PACK. HOWEVER TEMPERATURES ARE EXPECTED TO BE IN THE MID 30S AND COLDER SATURDAY NIGHT AND SUNDAY NIGHT SO MELT IS STOP. 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...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR CTZ001-013. NY...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR NYZ058>061-063>066. WINTER STORM WARNING FROM 7 AM THIS MORNING TO 7 AM EST THURSDAY FOR NYZ047>054-084. WINTER WEATHER ADVISORY FROM 9 AM THIS MORNING TO 7 AM EST THURSDAY FOR NYZ032-033-038>043-082-083. MA...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR MAZ001-025. VT...WINTER STORM WARNING FROM 5 AM EARLY THIS MORNING TO 7 AM EST THURSDAY FOR VTZ013>015. && $$ SYNOPSIS...IAA NEAR TERM...IAA/NAS SHORT TERM...IAA LONG TERM...IRL AVIATION...JPV HYDROLOGY...IAA
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
843 PM EST THU NOV 27 2014 .DISCUSSION... ...COLDER OVERNIGHT WITH WIND CHILLS DIPPING INTO THE MID TO UPPER 30S.. ...MARINE CONDITIONS WILL BECOME HAZARDOUS INTO FRIDAY MORNING... .UPDATE...SFC PRESSURE GRADIENT WILL BE TIGHTENING OVERNIGHT WITH SFC HIGH PRESSURE BUILDING INTO THE SE STATES. 12KM NAM INDICATES 925 MB WINDS MAY INCREASE TO 20-30 KNOTS KEEPING LOW LEVELS MIXED THROUGH MUCH OF THE NIGHT. WINDS WILL STAY NEAR 10 MPH OR DROP OFF TO 5-10 MPH SOME INTERIOR AND FAR SRN AREAS LATE. ON FCST UPDATE...HAVE LOWS MAINLY IN THE 40S...EXCEPT SOME UPPER 30S ACROSS FAR NRN INTERIOR AND POSSIBLY ACROSS THE SRN INTERIOR AS WELL IN AREAS WHERE WINDS DROP OFF. WIND CHILLS AROUND DAWN MAINLY IN THE MID TO UPPER 30S. DURATIONS FOR ADVISORY CRITERIA LOOK MARGINAL WITH WIND CHILLS NEAR 35 FOR AN HOUR OR TWO NEAR SUNRISE IN SOME SPOTS...LIKELY IN AREAS WHERE WINDS DROP BELOW 10 MPH. WILL CONTINUE TO MENTION WIND CHILLS IN THE ZFP FOR THE LATE NIGHT HOURS. && .AVIATION...MAINLY CLEAR THRU 28/15Z. NORTHERLY WINDS TONIGHT TO 10 KNOTS WILL BECOME NNE ON FRI WITH 10-13 KT WINDS THRU THE DAY. SOME MARINE STRATOCU WILL APPROACH THE COAST FROM KMLB S FRI AFTN. && .MARINE...18Z NAM/GFS/AND RECENT 13KM RAP MODELS INDICATE INCREASING WINDS TO AROUND 20-23 SUSTAINED FROM AROUND MIDNIGHT THROUGH MUCH OF THE NIGHT INTO FRIDAY MORNING. FOR UPDATE...INCREASED WINDS AND SEAS LATER TONIGHT INTO THE NEAR SHORE ZONES AS CONDITIONS WILL NOT BE VERY GOOD FOR EARLY MORNING BOATERS. SMALL CRAFT ADVISORIES ARE NOW IN EFFECT FOR ALL MARINE AREAS INTO PORTIONS OF THE DAY ON FRIDAY. && .PRELIMINARY POINT TEMPS/POPS... DAB 41 62 45 68 / 0 10 0 0 MCO 41 63 46 72 / 0 0 0 0 MLB 42 65 48 70 / 0 10 0 0 VRB 44 67 50 73 / 0 10 10 0 LEE 38 61 42 70 / 0 0 0 0 SFB 40 62 45 71 / 0 0 0 0 ORL 42 63 47 71 / 0 0 0 0 FPR 46 67 50 72 / 0 10 10 0 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST FRIDAY FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 PM EST FRIDAY FOR COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ SHORT TERM/AVIATION...VOLKMER LONG TERM....KELLY
AREA FORECAST DISCUSSION
NWS MIAMI FL
1241 AM EST WED NOV 26 2014 .AVIATION...MVFR CIGS WILL PREVAIL THROUGH MID MORNING WITH THE APPROACH AND PASSAGE OF A COLD FRONT. BRIEF PERIODS OF IFR POSSIBLE. A LINE OF THUNDERSTORMS OVER THE GULF WILL CONTINUE TO MOVE EASTWARD OVERNIGHT. IT`S HOLDING ITS OWN, SO A BRIEF PERIOD OF +TSRA WITH IFR OR LIFR ALONG WITH GUSTY WINDS OF 30-40 KT IS POSSIBLE AS THE LINE MOVES BY...DURING THIS OVERNIGHT AT KAPF AND TOWARDS DAWN EAST COAST TERMINALS. A FEW SHOWERS COULD IMPACT THE TERMINALS AHEAD OF THE LINE AS WELL. CIGS WILL IMPROVE DURING THE LATE MORNING AND BY AFTERNOON WED AT ALL TERMINALS. /GREGORIA && .PREV DISCUSSION... /ISSUED 1009 PM EST TUE NOV 25 2014/ UPDATE... SHOWERS AND STORMS PROGRESSING MUCH SLOWER TO THE SOUTH AND EAST THAN GUIDANCE PROJECTS, AND THIS HAS BEEN THE CASE FOR SEVERAL RUNS. THEREFORE HAVE SLOWED CHC AND LIKELY POPS BY ABOUT 6HRS FROM PREVIOUS FORECAST. ACROSS THE GULF WATERS AND EXTREME NW POPS WERE LEFT ALONE. WITH THE DEEP WARM, MOIST SOUTHERLY FLOW ACROSS SOUTH FLORIDA, SHOWERS HAVE DEVELOPED IN THE STRAITS AND PERHAPS WILL CROSS INTO THE ATLANTIC WATERS AND MIAMI DADE OVER THE NEXT SEVERAL HOURS ALTHOUGH SCATTERED. WITH THE FRONT CROSSING AT THE MOST CLIMATOLOGICALLY UNFAVORABLE TIME TOMORROW MORNING, AND THE MID LEVEL UVV/VORTICITY QUICKLY WEAKENING, NOT EXPECTING MUCH LIFT WITH THE BOUNDARY TOMORROW MORNING. THIS SEEMS TO BE REFLECTED IN THE MODELS, WITH QPF QUICKLY DROPPING OFF ACROSS THE EAST COAST INTO TOMORROW MORNING. ANY CHANCE FOR A STRONGER STORM WITH DECENT WIND GUSTS WILL REMAIN RESERVED ACROSS THE NW CWA AND LAKE REGION LATE TONIGHT. PREV DISCUSSION... /ISSUED 656 PM EST TUE NOV 25 2014/ AVIATION...MVFR CIGS ARE LIKELY TO DEVELOP OVERNIGHT. IFR CIGS ARE POSSIBLE, BUT LESS CERTAIN. GUIDANCE HAS BEEN TOO AGGRESSIVE PAST TWO NIGHTS SHOWING IFR TO ONLY NOT OCCUR AT MOST LOCALES. FOR THIS REASON, WENT WITH PREVAILING MVFR CIGS WITH A SCT005 AND WILL CLOSELY MONITOR TRENDS. IMPRESSIVE TROUGH DIGGING INTO THE GULF WITH CONVECTION ALL THE WAY TO THE YUCATAN. AS THIS SLIDES EAST, THERE IS THE POTENTIAL FOR A BROKEN LINE OF TSRA TO MOVE THROUGH SOUTH FL. HOWEVER, THE STORMS IN THE GULF ARE ONLY SLOWLY PROGRESSING EASTWARD AND POLYGON TIME TRACKING SUGGESTS A LATE NIGHT ARRIVAL AFTER MIDNIGHT FOR KAPF AND NOT UNTIL DAWN FOR THE EAST COAST. LATEST HRRR RUN SHOWS NO QPF EAST COAST UNTIL AFTER 10Z. THIS SEEMS REASONABLE WITH OUR TIMING ANALYSIS, SO HAVE FOLLOWED THIS. IFR OR LIFR VIS/CIGS ARE POSSIBLE IN ANY HEAVIER TSRA WHICH MOVES THROUGH WITH IMPACT POTENTIAL HIGHEST FROM 05-09Z AT KAPF AND 09-14Z FOR THE EAST COAST TERMINALS. GREATEST THREAT KAPF TO KFLL AND POINTS NORTH. GUST WIND POTENTIAL ~40KT POSSIBLE. ANY SIGNIFICANT IMPACTS WOULD BE BRIEF THOUGH. THX CWSU MIAMI FOR COLLABORATION! /GREGORIA PREV DISCUSSION... /ISSUED 356 PM EST TUE NOV 25 2014/ A FEW STRONG STORMS POSSIBLE LAKE OKEECHOBEE/WEST COAST TONIGHT... ROUGH MARINE CONDITIONS ON WEDNESDAY FOR ALL SOUTH FLORIDA WATERS... DRIER AND COOLER WEATHER THIS THANKSGIVING WEEKEND... SHORT TERM... A MID TO UPPER LEVEL TROUGH OF LOW PRESSURE THAT EXTENDED FROM THE GREAT LAKES SOUTHWEST INTO THE NORTHWEST GULF OF MEXICO WILL CONTINUE TO MOVE TO THE EAST TONIGHT AND BE LOCATED OVER THE EASTERN UNITED STATES BY WEDNESDAY MORNING. THIS WILL PUSH HIGH PRESSURE OVER THE WESTERN ATLANTIC WATERS FURTHER EASTWARD INTO THE ATLANTIC. LOW PRESSURE OVER THE EASTERN GULF OF MEXICO WILL THEN MOVE NORTHEAST ALONG THE STATIONARY FRONT THAT IS LOCATED OVER CENTRAL FLORIDA. THIS WEATHER PATTERN WILL ALLOW FOR THE SURFACE WINDS TO BECOME MORE SOUTHWEST OVER SOUTH FLORIDA TONIGHT BRINGING IN THE TROPICAL MOISTURE FROM THE GULF OF MEXICO INTO SOUTH FLORIDA. THEREFORE...POPS WILL BE ON AN INCREASE OVER SOUTH FLORIDA TONIGHT FROM WEST TO EAST...SCATTERED TO NUMEROUS BY LATE TONIGHT WITH THE HIGHEST POPS OVER THE LAKE OKEECHOBEE REGION AND WEST COAST METRO AREAS. THERE IS ALSO A THREAT OF A FEW STRONG STORMS OVER THE LAKE OKEECHOBEE AND WEST COAST METRO AREAS LATE THIS AFTERNOON INTO TONIGHT...AS THE LATEST SHORT RANGE MODELS CONTINUE TO INDICATE A MID LEVEL JET OF 50 KNOTS MOVING THROUGH CENTRAL FLORIDA TONIGHT ASSOCIATED WITH THE LOW. THE PRIMARY IMPACTS FROM THE STRONG STORMS WILL BE FREQUENT LIGHTNING STRIKES...GUSTY WINDS...AND HEAVY RAINFALL THIS AFTERNOON INTO EARLY THIS EVENING. THE LOW WILL CONTINUE TO MOVE NORTHEAST UP THE EAST COAST OF THE UNITED STATES ON WEDNESDAY. THIS WILL ALLOW FOR THE STATIONARY FRONT TO BECOME A COLD FRONT TONIGHT...AND PUSH SOUTHWARD THROUGH SOUTH FLORIDA WEDNESDAY MORNING BEFORE MOVING INTO THE FLORIDA KEYS WEDNESDAY AFTERNOON. THEREFORE...THE POPS WILL REMAIN IN THE SCATTERED TO NUMEROUS RANGE WEDNESDAY MORNING BEFORE DECREASING IN COVERAGE WEDNESDAY AFTERNOON. HIGH PRESSURE WILL THEN BUILD INTO THE SOUTHEASTERN UNITED STATES WEDNESDAY NIGHT THROUGH FRIDAY KEEPING A NORTHERLY WIND FLOW OVER SOUTH FLORIDA. THIS NORTHERLY WIND FLOW WILL BRING IN DRIER AND COOLER WEATHER TO SOUTH FLORIDA FOR THANKSGIVING AND FRIDAY. LOWS WILL BE IN THE 40S OVER MOST OF SOUTH FLORIDA FOR WEDNESDAY NIGHT AND THURSDAY NIGHT...EXCEPT FOR LOWER TO MID 50S EAST COAST METRO AREAS. HIGHS WILL BE IN THE LOWER TO MID 70S FOR THANKSGIVING DAY AND FOR FRIDAY. LONG TERM... THE HIGH WILL THEN MOVE SLOWLY EAST INTO THE WESTERN ATLANTIC WATERS THIS THANKSGIVING WEEKEND ALLOWING FOR THE WINDS TO SLOWLY SWING TO A EASTERLY DIRECTION AND BECOME BREEZY. THIS WILL KEEP SOUTH FLORIDA DRY AND ALLOW FOR THE TEMPERATURES TO SLOWLY WARM UP THROUGH THE WEEKEND...WITH HIGHS IN THE MID TO UPPER 70S AND LOWS IN THE 50S EXCEPT 60S EAST COAST METRO AREAS. MARINE... THE WINDS WILL SWING FROM A SOUTHERLY DIRECTION OF 10 TO 15 KNOTS TONIGHT TO A NORTHERLY DIRECTION ON WEDNESDAY AND INCREASE QUICKLY TO 20 TO 25 KNOTS WITH GUSTS GETTING CLOSE TO GALE FORCE IN THE OFFSHORE GULF WATERS. THE NORTHERLY WINDS WILL CONTINUE WEDNESDAY NIGHT INTO THANKSGIVING DAY AS THE WIND SPEEDS DECREASE TO 15 TO 20 KNOTS. BOTH THE ATLANTIC AND GULF SEAS WILL REMAIN BELOW 6 FEET TONIGHT BEFORE INCREASING TO AT LEAST 7 FEET ON WEDNESDAY. THE OFFSHORE GULF WATERS COULD EVEN GET UP TO 9 TO 11 FEET ON WEDNESDAY. THEREFORE...IT LOOKS LIKE AN SCA WILL BE NEEDED SOON FOR ALL OF THE SOUTH FLORIDA WATERS FOR THE WINDS AND SEAS IN THE ATLANTIC AND GULF WATERS...FOR WEDNESDAY INTO WEDNESDAY NIGHT. THE THREAT OF RIP CURRENTS WILL ALSO CONTINUE ALONG THE EAST COAST BEACHES THIS THANKSGIVING WEEKEND AND FOR THE GULF BEACHES OF SOUTH FLORIDA FOR WEDNESDAY. FIRE WEATHER... THE RELATIVE HUMIDITY SHOULD FALL BELOW THE 35 PERCENT CRITICAL VALUE ON THANKSGIVING DAY OVER SOUTH FLORIDA DUE TO DRIER AIR WORKING INTO THE AREA FROM THE NORTH. HOWEVER...THE ERC WILL REMAIN IN THE UPPER TEENS TO LOWER 20S AND THE 20 FOOT WINDS WILL REMAIN BELOW 15 MPH ON THANKSGIVING DAY. THEREFORE...NO FIRE DANGER STATEMENT WILL BE ISSUED FOR SOUTH FLORIDA FOR THANKSGIVING DAY. && .PRELIMINARY POINT TEMPS/POPS... WEST PALM BEACH 49 73 51 71 / 10 0 0 10 FORT LAUDERDALE 55 75 56 71 / 10 0 0 10 MIAMI 56 76 57 72 / 10 0 0 10 NAPLES 48 73 50 69 / 0 0 0 0 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...HIGH RIP CURRENT RISK FROM 7 AM EST THIS MORNING THROUGH THIS EVENING FOR FLZ069. AM...SMALL CRAFT ADVISORY FROM 9 AM THIS MORNING TO 5 PM EST THURSDAY FOR AMZ650-651-670-671. GM...SMALL CRAFT ADVISORY FROM 5 AM EARLY THIS MORNING TO 7 PM EST THIS EVENING FOR GMZ656-657-676. && $$
AREA FORECAST DISCUSSION
NWS GOODLAND KS
123 PM MST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 123 PM MST WED NOV 26 2014 AS OF 2 PM CST...1 PM MST...SKIES ACROSS THE TRI-STATE REGION VARIED FROM MOSTLY CLEAR TO OVERCAST. TEMPERATURES WERE IN THE 40S WHERE CLOUDS HAVE BROKEN UP AND IN THE LOW TO UPPER 30S WHERE PERSISTENT CLOUDS REMAIN. WINDS WERE FROM THE NORTH AT 10 TO 15 MPH AND ON A GRADUAL WEAKENING TREND. WSR-88D RADAR DATA HAS NOTED A DOWNWARD TREND IN RADAR REFLECTIVITIES AS THE BAND OF LIGHT SNOW SHOWERS FINALLY BEGINS TO DIMINISH. SNOW APPEARS TO BE THE RESULT OF LOW LEVEL FRONTOGENESIS OVER NORTHEAST COLORADO AS NO MAJOR DISTURBANCES HAVE BEEN OBSERVED BY WATER VAPOR IMAGERY. FOR THE REST OF THE AFTERNOON AND TONIGHT...MAIN FORECAST CONCERN IS DECREASING SNOW SHOWER ACTIVITY THROUGH THE AFTERNOON WITH POSSIBLE BRIEF REDEVELOPMENT THIS EVENING. LATEST RAP GUIDANCE/HRRR GUIDANCE SEEMS TO BE HANDLING THIS SITUATION BEST SO HAVE LEANED ON THESE SOLUTIONS. RAP FORECAST SOUNDINGS INDICATE THAT THE ICE CRYSTAL GROWTH ZONE LOSES SATURATION THIS AFTERNOON...LEADING TO A DECREASE IN PRECIPITATION. THAT TREND IS ALREADY BEING REALIZED. RAP SOUNDINGS THEN INDICATE ONE MORE PUSH OF MOISTURE IN THE ICE CRYSTAL GROWTH ZONE LATER THIS EVENING BEFORE THE ENTIRE ATMOSPHERIC PROFILE DESATURATES. ATTEMPTED TO SHOW THIS UP AND DOWN TREND WITH THE POPS THROUGH THIS EVENING AND THEN FORECAST DRY WEATHER AFTER MIDNIGHT. SKIES GRADUALLY CLEAR LATE TONIGHT WITH A QUICK DROP IN TEMPS ONCE CONDITIONS ARE CONDUCIVE FOR RADIATIONAL COOLING. FOR THANKSGIVING DAY...OVERALL CALM WEATHER IS ANTICIPATED WITH NO PRECIPITATION EXPECTED. ATMOSPHERIC PROFILE BECOMES QUITE DRY BY AFTERNOON...ESPECIALLY IN THE LOW LEVELS...AS DRY AIR ADVECTION CONTINUES FROM THE SOUTHWEST. A LEE TROUGH DEEPENING OVER CENTRAL COLORADO SHALL LEAD TO PERSISTENT SOUTHWEST FLOW THROUGHOUT THE DAY. WARM 850 MB TEMPS ALSO ADVECT IN SO EXPECTING A WARM...ABOVE NORMAL DAY. ONE THING THAT IS INTERESTING ABOUT TOMORROW IS FORECAST SOUNDINGS INDICATE THAT A PERSISTENT INVERSION NEAR THE SURFACE MAY PREVENT SOME STRONGER WIND GUSTS ALOFT FROM BEING REALIZED AT THE SURFACE. WILL NEED TO WATCH THIS CAREFULLY AS LOW RELATIVE HUMIDITY WILL BE PRESENT OVER CHEYENNE AND KIT CARSON COUNTIES IN COLORADO AND SHERMAN...WALLACE...GREELEY AND POSSIBLY WICHITA COUNTIES IN KANSAS. OVERALL...KEPT FORECAST WINDS LIGHT BUT NERVOUS ABOUT STRONGER WINDS ALOFT MIXING DOWN. IF WINDS ARE REALIZED...A FIRE WEATHER HIGHLIGHT MAY BE REQUIRED. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 1204 PM MST WED NOV 26 2014 BROAD ZONAL FLOW WILL PERSIST THROUGH SATURDAY ACROSS THE CENTRAL CONUS OVER A LOW AMPLITUDE RIDGE CENTERED OVER THE DESERT SOUTHWEST. THIS WILL RESULT IN DRY CONDITIONS AND MUCH ABOVE NORMAL TEMPERATURES. RELATIVE HUMIDITY WILL DROP TO NEAR CRITICAL FIRE WEATHER VALUES EACH AFTERNOON...HOWEVER WIND FORECASTS ARE RELATIVELY LIGHT AND NO FIRE WEATHER HIGHLIGHTS ARE ANTICIPATED. A NORTHERN STREAM SHORTWAVE WILL SUPPORT A SURFACE COLD FRONT WHICH WILL MOVE THROUGH THE CENTRAL HIGH PLAINS SATURDAY NIGHT. SYNOPTIC SCALE FORCING FOR PRECIPITATION WILL REMAIN NORTH OF THE LOCAL AREA AND FROPA WILL LIKELY BE DRY. TEMPERATURES ON SUNDAY WILL BE CLOSER TO NORMAL...THEN COOL TO BELOW NORMAL ON MONDAY WHICH WILL BE THE COLDEST DAY OF THIS PERIOD. TEMPERATURES BOUNCE BACK TO ABOVE NORMAL ON TUESDAY UNDER SHORTWAVE RIDGING WITH CONTINUED DRY CONDITIONS. FINALLY...ON WEDNESDAY A SHORTWAVE TROUGH IN THE SOUTHERN STREAM WILL MOVE OUT OF THE SOUTHERN ROCKIES AND EMERGE ONTO THE ADJACENT PLAINS...WITH A CHANCE FOR RAIN AND SNOW. TIMING AND AMOUNTS WITH THE SYSTEM STILL VERY UNCERTAIN WITH SIGNIFICANT MODEL DIFFERENCES AT THIS TIME RANGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1028 AM MST WED NOV 26 2014 BAND OF MVFR CLOUDS WITH SOME SNOW IS MOVING TOWARDS KGLD AT 1700Z. MVFR STRATUS HAS REACHED TAF SITE BUT NOT EXPECTING ANY VISIBILITY RESTRICTIONS FROM SNOW. CEILINGS AT KGLD SHOULD IMPROVE BY 2100Z. CLOUD DECK AROUND 5000 FT REACHES KMCK THIS AFTERNOON WITH NO SNOW ANTICIPATED. NORTHWEST WINDS WEAKEN TODAY AND AFTER A PERIOD OF LIGHT/VARIABLE THIS EVENING...WINDS BECOME SOUTHWEST AT KGLD AND SOUTH AT KMCK AS A LEE TROUGH DEVELOPS TO THE WEST. SOUTH WINDS INCREASE IN SPEED AFTER SUNRISE TOMORROW UNDER MOSTLY CLEAR SKIES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ SHORT TERM...RRH LONG TERM...024 AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1215 PM MST WED NOV 26 2014 .UPDATE... ISSUED AT 1028 AM MST WED NOV 26 2014 LIGHT SNOW CONTINUES TO SPREAD IN FROM THE NORTHWEST. BASED ON AN ANALYSIS OF FORECAST RAP SOUNDINGS...SNOW MAY CONTINUE INTO THE EARLY AFTERNOON HOURS BEFORE A LAYER OF DRY AIR BEGINS TO MOVE INTO THE ICE CRYSTAL GROWTH ZONE. UPDATED THE FORECAST TO REFLECT CURRENT TRENDS BY INCREASING CHANCES OF PRECIP AND MAKING ADJUSTMENTS TO QPF/SNOW GRIDS. EARLIER HAZARDOUS CONDITIONS WITH ICY ROADS SHOULD NO LONGER BE AN ISSUE AS SOME SUN HAS REACHED THE GROUND AND TEMPERATURES A FEW DEGREES HIGHER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 235 AM MST WED NOV 26 2014 LATEST UPPER AIR ANALYSIS INDICATES A TROUGH OF LOW PRESSURE OVER EASTERN SOUTH DAKOTA. SATELLITE AND RADAR SHOW A BAND OF CLOUDS WITH SOME LIGHT SNOW OVER THE TRI-STATE AREA. MOST OF THE SNOWFALL IS OVER EASTERN COLORADO. AS SUNRISE APPROACHES ANTICIPATE THE SNOWFALL TO DISSIPATE TOWARD THE WEST AS THE UPPER LEVEL TROUGH AXIS MOVES THROUGH THE AREA WITH SUBSIDENCE FOLLOWING THE TROUGH AXIS. SNOWFALL SHOULD BE COMPLETELY WEST OF THE AREA BY OR SHORTLY AFTER SUNRISE. TODAY THE OVERCAST SKIES WILL GRADUALLY BREAKUP AS DRIER AIR MOVES IN FROM THE NORTHWEST. THERE IS SOME WEAK ISENTROPIC LIFT OVER THE AREA TODAY BUT CONDENSATION PRESSURE DEFICITS ARE GENERALLY TOO LARGE FOR ANY PRECIP. TO BE GENERATED FROM THE MEAGER LIFT SO WILL CONTINUE WITH A DRY FORECAST FOR THE DAY. NORTHWEST WINDS WILL DECLINE FROM WEST TO EAST TODAY AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA. MODELS CONTINUE TO TREND SLOWER WITH THE WARM AIR ADVECTION THAT FOLLOWS THE HIGH PRESSURE INTO THE AREA...SO HAVE COOLED HIGHS TODAY AS A RESULT. TONIGHT SKIES WILL BECOME MOSTLY CLEAR AS DRY AIR CONTINUES TO MOVE OVER THE AREA IN THE NORTHWEST UPPER LEVEL FLOW. LOWS WILL BE COOLER THAN LAST NIGHT DESPITE THE WARM AIR ADVECTION DUE TO RADIATIONAL COOLING AND LOWER DEW POINTS THAN LAST NIGHT. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 1204 PM MST WED NOV 26 2014 BROAD ZONAL FLOW WILL PERSIST THROUGH SATURDAY ACROSS THE CENTRAL CONUS OVER A LOW AMPLITUDE RIDGE CENTERED OVER THE DESERT SOUTHWEST. THIS WILL RESULT IN DRY CONDITIONS AND MUCH ABOVE NORMAL TEMPERATURES. RELATIVE HUMIDITY WILL DROP TO NEAR CRITICAL FIRE WEATHER VALUES EACH AFTERNOON...HOWEVER WIND FORECASTS ARE RELATIVELY LIGHT AND NO FIRE WEATHER HIGHLIGHTS ARE ANTICIPATED. A NORTHERN STREAM SHORTWAVE WILL SUPPORT A SURFACE COLD FRONT WHICH WILL MOVE THROUGH THE CENTRAL HIGH PLAINS SATURDAY NIGHT. SYNOPTIC SCALE FORCING FOR PRECIPITATION WILL REMAIN NORTH OF THE LOCAL AREA AND FROPA WILL LIKELY BE DRY. TEMPERATURES ON SUNDAY WILL BE CLOSER TO NORMAL...THEN COOL TO BELOW NORMAL ON MONDAY WHICH WILL BE THE COLDEST DAY OF THIS PERIOD. TEMPERATURES BOUNCE BACK TO ABOVE NORMAL ON TUESDAY UNDER SHORTWAVE RIDGING WITH CONTINUED DRY CONDITIONS. FINALLY...ON WEDNESDAY A SHORTWAVE TROUGH IN THE SOUTHERN STREAM WILL MOVE OUT OF THE SOUTHERN ROCKIES AND EMERGE ONTO THE ADJACENT PLAINS...WITH A CHANCE FOR RAIN AND SNOW. TIMING AND AMOUNTS WITH THE SYSTEM STILL VERY UNCERTAIN WITH SIGNIFICANT MODEL DIFFERENCES AT THIS TIME RANGE. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1028 AM MST WED NOV 26 2014 BAND OF MVFR CLOUDS WITH SOME SNOW IS MOVING TOWARDS KGLD AT 1700Z. MVFR STRATUS HAS REACHED TAF SITE BUT NOT EXPECTING ANY VISIBILITY RESTRICTIONS FROM SNOW. CEILINGS AT KGLD SHOULD IMPROVE BY 2100Z. CLOUD DECK AROUND 5000 FT REACHES KMCK THIS AFTERNOON WITH NO SNOW ANTICIPATED. NORTHWEST WINDS WEAKEN TODAY AND AFTER A PERIOD OF LIGHT/VARIABLE THIS EVENING...WINDS BECOME SOUTHWEST AT KGLD AND SOUTH AT KMCK AS A LEE TROUGH DEVELOPS TO THE WEST. SOUTH WINDS INCREASE IN SPEED AFTER SUNRISE TOMORROW UNDER MOSTLY CLEAR SKIES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...RRH SHORT TERM...JTL LONG TERM...024 AVIATION...RRH
AREA FORECAST DISCUSSION
NWS GOODLAND KS
1028 AM MST WED NOV 26 2014 .UPDATE... ISSUED AT 1028 AM MST WED NOV 26 2014 LIGHT SNOW CONTINUES TO SPREAD IN FROM THE NORTHWEST. BASED ON AN ANALYSIS OF FORECAST RAP SOUNDINGS...SNOW MAY CONTINUE INTO THE EARLY AFTERNOON HOURS BEFORE A LAYER OF DRY AIR BEGINS TO MOVE INTO THE ICE CRYSTAL GROWTH ZONE. UPDATED THE FORECAST TO REFLECT CURRENT TRENDS BY INCREASING CHANCES OF PRECIP AND MAKING ADJUSTMENTS TO QPF/SNOW GRIDS. EARLIER HAZARDOUS CONDITIONS WITH ICY ROADS SHOULD NO LONGER BE AN ISSUE AS SOME SUN HAS REACHED THE GROUND AND TEMPERATURES A FEW DEGREES HIGHER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 235 AM MST WED NOV 26 2014 LATEST UPPER AIR ANALYSIS INDICATES A TROUGH OF LOW PRESSURE OVER EASTERN SOUTH DAKOTA. SATELLITE AND RADAR SHOW A BAND OF CLOUDS WITH SOME LIGHT SNOW OVER THE TRI-STATE AREA. MOST OF THE SNOWFALL IS OVER EASTERN COLORADO. AS SUNRISE APPROACHES ANTICIPATE THE SNOWFALL TO DISSIPATE TOWARD THE WEST AS THE UPPER LEVEL TROUGH AXIS MOVES THROUGH THE AREA WITH SUBSIDENCE FOLLOWING THE TROUGH AXIS. SNOWFALL SHOULD BE COMPLETELY WEST OF THE AREA BY OR SHORTLY AFTER SUNRISE. TODAY THE OVERCAST SKIES WILL GRADUALLY BREAKUP AS DRIER AIR MOVES IN FROM THE NORTHWEST. THERE IS SOME WEAK ISENTROPIC LIFT OVER THE AREA TODAY BUT CONDENSATION PRESSURE DEFICITS ARE GENERALLY TOO LARGE FOR ANY PRECIP. TO BE GENERATED FROM THE MEAGER LIFT SO WILL CONTINUE WITH A DRY FORECAST FOR THE DAY. NORTHWEST WINDS WILL DECLINE FROM WEST TO EAST TODAY AS A SURFACE HIGH PRESSURE MOVES INTO THE AREA. MODELS CONTINUE TO TREND SLOWER WITH THE WARM AIR ADVECTION THAT FOLLOWS THE HIGH PRESSURE INTO THE AREA...SO HAVE COOLED HIGHS TODAY AS A RESULT. TONIGHT SKIES WILL BECOME MOSTLY CLEAR AS DRY AIR CONTINUES TO MOVE OVER THE AREA IN THE NORTHWEST UPPER LEVEL FLOW. LOWS WILL BE COOLER THAN LAST NIGHT DESPITE THE WARM AIR ADVECTION DUE TO RADIATIONAL COOLING AND LOWER DEW POINTS THAN LAST NIGHT. .LONG TERM...(THANKSGIVING DAY THROUGH TUESDAY) ISSUED AT 235 AM MST WED NOV 26 2014 THANKSGIVING DAY THROUGH FRIDAY WILL CONTINUE TO SEE A WARMING TREND WITH TEMPERATURES RANGING FROM 10 TO 20 DEGREES ABOVE NORMAL. THE UPPER LEVEL FLOW WILL TRANSITION FROM THE NORTHWEST TO THE WEST. THERE WILL BE MULTIPLE UPPER LEVEL SHORT WAVE TROUGHS MOVING OVER THE AREA...BUT DUE TO THE DRY ENVIRONMENT IN PLACE DO NOT EXPECT MORE THAN A FEW CLOUDS WITH EACH TROUGH PASSAGE. ZONAL FLOW WILL CONTINUE SATURDAY AND SUNDAY. A RIDGE WILL MOVE INTO THE ROCKIES SUNDAY NIGHT AND INTO THE PLAINS MONDAY. THE RIDGE WILL SHIFT EAST TUESDAY WITH FLOW BECOMING SOUTHWESTERLY AHEAD OF A TROUGH MOVING INTO THE WESTERN CONUS. A SURFACE TROUGH WILL RESIDE OVER EASTERN COLORADO SATURDAY AND THEN SHIFT EAST SUNDAY AS A COLD FRONT MOVES SOUTH INTO THE CENTRAL PLAINS. HIGH PRESSURE WILL BUILD INTO THE CENTRAL PLAINS MONDAY AND TUESDAY. THE WEATHER WILL REMAIN DRY AND MILD THROUGH THIS PERIOD SINCE THE RIDGE WILL SHUNT STORMS ACROSS THE NORTHERN CONUS. 850MB TEMPERATURES WILL BE WARM ENOUGH TO SUPPORT MAX TEMPERATURES IN THE MID TO UPPER 60S SATURDAY. MAX TEMPERATURES SUNDAY AND MONDAY WILL BE COOLER BEHIND THE FRONT WITH READINGS IN THE 40S. TEMPERATURES SHOULD WARMUP TO THE UPPER 50S TUESDAY. MIN TEMPERATURES SATURDAY NIGHT WILL COOL TO THE UPPER 20S. TEMPERATURES SUNDAY AND MONDAY NIGHTS WILL FALL INTO THE TEENS AND LOW 20S RESPECTIVELY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1028 AM MST WED NOV 26 2014 BAND OF MVFR CLOUDS WITH SOME SNOW IS MOVING TOWARDS KGLD AT 1700Z. MVFR STRATUS HAS REACHED TAF SITE BUT NOT EXPECTING ANY VISIBILITY RESTRICTIONS FROM SNOW. CEILINGS AT KGLD SHOULD IMPROVE BY 2100Z. CLOUD DECK AROUND 5000 FT REACHES KMCK THIS AFTERNOON WITH NO SNOW ANTICIPATED. NORTHWEST WINDS WEAKEN TODAY AND AFTER A PERIOD OF LIGHT/VARIABLE THIS EVENING...WINDS BECOME SOUTHWEST AT KGLD AND SOUTH AT KMCK AS A LEE TROUGH DEVELOPS TO THE WEST. SOUTH WINDS INCREASE IN SPEED AFTER SUNRISE TOMORROW UNDER MOSTLY CLEAR SKIES. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && $$ UPDATE...RRH SHORT TERM...JTL LONG TERM...FS/JTL AVIATION...RRH
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
315 PM EST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 315 PM EST WED NOV 26 2014 ...SOME SLUSHY SNOW ACCUMULATIONS POSSIBLE LATE TONIGHT OVER SOUTHERN PARTS OF EAST KENTUCKY... 19Z SFC ANALYSIS SHOWS EAST KENTUCKY IN BETWEEN TWO AREAS OF LOW PRESSURE. TO THE EAST...A COASTAL LOW IS NOW PASSING NORTH OF CAPE HATTERAS...WHILE A MORE MODERATE STRENGTH SFC LOW IS LOCATED OVER CENTRAL MISSOURI ON ITS PATH SOUTHEAST INTO THE TENNESSEE VALLEY. IN THE GAP BETWEEN THESE SYSTEMS ENOUGH CLEARING TOOK PLACE FOR MOST OF THE AREA THAT TEMPERATURES CLIMBED INTO UPPER 40S AND LOWER 50S THIS AFTERNOON. WINDS ARE GENERALLY LIGHT WHILE DEWPOINTS ARE FOUND IN THE MID AND UPPER 20S...THOUGH WITH SOME 30S IN THE FAR EAST. THE MODELS ARE IN PRETTY GOOD AGREEMENT...NOW THAT THE GFS IS BREAKING TOWARD THE ECMWF AND NAM...ALOFT WITH THE CLIPPER SYSTEM DROPPING INTO THE TENNESSEE VALLEY TONIGHT. THEY ALL SHOW THE ENERGY...ASSOCIATED WITH EASTERN PORTION OF THE LARGE TROUGH IN PLACE OVER THE OHIO VALLEY...LIFTING NORTHEAST INTO EASTERN NEW ENGLAND BY THURSDAY MORNING. AT THE SAME TIME...A SECONDARY BATCH OF ENERGY WITHIN THE LARGER TROUGH WILL RIDE SOUTHEAST FROM THE EAST CENTRAL PLAINS TO THE TENNESSEE VALLEY...THOUGH SHEARING AS IT PASSES BY KENTUCKY TO THE SOUTH TONIGHT. FOLLOWING THIS...THE WHOLE TROUGH BODILY MOVES OUT OF THE REGION AND RISING HEIGHTS FOLLOW. HAVE FOLLOWED A GENERAL MODEL BLEND FOR THE SHORT TERM PORTION THE FORECAST WITH SOME CAUTIOUS FAVORING OF THE HIGHER RESOLUTION NAM12 AND HRRR FOR WX DETAILS. SENSIBLE WEATHER WILL FEATURE A QUIET EVENING AS HIGH CLOUDS OVERTAKE THE SKY AND LOWER WITH TIME. A WEAKENING AREA OF LOW PRESSURE WILL SLIDE SOUTH THROUGH SOUTHERN KENTUCKY AND INTO EASTERN TENNESSEE. THIS WILL BRING WITH IT A NARROW BAND OF PCPN CAPABLE OF BECOMING SNOW GIVEN THE EXPECTED WETBULB EFFECT WHEN IT STARTS COMING DOWN MODERATELY ACROSS OUR SOUTHERN COUNTIES. HOWEVER...SFC TEMPERATURES WILL BE NEAR 32 DEGREES AT THEIR COLDEST LIKELY PREVENTING MUCH ACCUMULATION ON ANYTHING MORE THAN GRASSY AND ELEVATED SURFACES AND THEN MAINLY ON THE RIDGES AS THE VALLEYS REMAIN A MIX OF RAIN AND SNOW. THIS IS A DISTURBINGLY SIMILAR SITUATION AS COMPARED TO LAST NIGHT IN THE EAST WHERE THE HEAVIER PCPN STAYED JUST OFF TO THE EAST. THESE SMALL SCALE DETAILS MAKE ALL THE DIFFERENCE IN MARGINAL SITUATIONS AS THIS. HOWEVER...CANNOT RULE OUT A HEAVIER BURST OR TWO OF SNOW THAT COULD CAUSE A SLUSHY ACCUMULATION ON THE ROADS. THIS SHOULD NOT LAST LONG...THOUGH...AS ROAD TEMPERATURES ARE CURRENTLY IN THE 40S AND 50S AND WILL ONLY SLOWLY FALL WITH THE PCPN TONIGHT. HAVE ISSUED AN SPS TO DEAL WITH THE POTENTIAL FOR A SLUSHY INCH OF SNOW THAT SHOULD HAVE A MINIMAL IMPACT ON TRAVELERS TONIGHT. THE LIGHT SNOW/RAIN PULLS OUT OF THE AREA EARLY THURSDAY WITH COOLER TEMPERATURES TO FOLLOW AS HIGH PRESSURE MOVES THROUGH THE SOUTHERN APPALACHIANS INTO FRIDAY MORNING. ONCE AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME TERRAIN BASED ADJUSTMENTS TONIGHT INTO THURSDAY MAINLY TO LOWER THE RIDGES IN OUR SOUTHERN COUNTIES DUE TO THE PCPN AND ANTICIPATED WETBULBING. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE DRIER MAV AND WETTER MET NUMBERS TONIGHT INTO THURSDAY MORNING AND THEN MATCHED THEIR DRY CONSENSUS INTO FRIDAY MORNING. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 245 PM EST WED NOV 26 2014 THE SYNOPTIC PATTERN THROUGH THE LONG TERM PERIOD WILL FEATURE A PROGRESSIVE FLOW ALOFT WITH A GENERAL SOUTHWEST FLOW IN THE LOW LEVELS AS AN ELONGATED AREA OF SURFACE HIGH PRESSURE STRETCHES OUT FROM THE DEEP SOUTH EASTWARD INTO THE WESTERN ATLANTIC. A COLD FRONT WILL DROP SOUTH INTO THE REGION ON MONDAY...AND THEN STALL OUT IN OUR VICINITY AS THE SPONSORING UPPER TROUGH PASSES BY TO THE NORTH. A SECOND TROUGH WILL THEN FOLLOW A SIMILAR TRACK AND PASS BY TO OUR NORTH MIDWEEK. FORECAST MODELS DIFFER ON THE STRENGTH OF THIS SHORTWAVE AND THE RESULTING IMPACT IT WILL HAVE ON THE FRONT AND FORECASTER CONFIDENCE DROPS BELOW AVERAGE BY THE END OF THE PERIOD. OUR SENSIBLE WEATHER WILL FEATURE A MODERATING TREND OVER THE THANKSGIVING HOLIDAY WEEKEND. UNFORTUNATELY...THE WARMING TEMPS WILL BE ACCOMPANIED BY INCREASING CLOUDS AND A FEW SHOWERS BY SATURDAY NIGHT INTO THE DAY ON SUNDAY AS LOW LEVEL MOISTURE INCREASES. RAIN CHANCES THEN INCREASE DRAMATICALLY SUNDAY NIGHT INTO MONDAY AS THE FRONT DROPS INTO THE AREA. BEYOND MONDAY...TEMPS AND RAIN CHANCES ARE PROBLEMATIC DUE TO THE MODEL DIFFERENCES REGARDING THE PLACEMENT OF THE FRONT. SIDING WITH A MODEL BLEND YIELDS NEAR NORMAL TEMPS AND A CHANCE OF RAIN EACH PERIOD THROUGH WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 100 PM EST WED NOV 26 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE AREA INTO THE EVENING BEFORE THE CIGS START TO DROP...PARTICULARLY AT THE SOUTHERN SITES. EXPECT AN AREA OF RAIN AND SNOW TO SLIDE THROUGH THE CUMBERLAND VALLEY OVERNIGHT WITH A GOOD CHANCE OF DROPPING VIS AND CIGS INTO THE MVFR AND IFR RANGES AS THE SNOW DEVELOPS AND PASSES THROUGH. THE SME AND LOZ SITES WILL LIKELY SEE THE WORST CONDITIONS...THOUGH IF THE PCPN IS NOT ABLE TO WET BULB TO SNOW EFFECTIVELY...AT LEAST THE VIS WILL NOT BE AS LOW AS CURRENTLY FORECASTED. EXPECT THE CONDITIONS TO GRADUALLY IMPROVE THROUGH THE DAY THURSDAY ONCE THIS WAVE PASSES... BUT CIGS WILL PROBABLY BE MVFR AT MOST SITES THROUGH THE MORNING. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE NIGHT BEFORE PICKING UP A BIT FROM THE NORTHWEST INTO THE MORNING IN THE WAKE OF THE SFC LOW. && .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...GREIF LONG TERM...ABE AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS JACKSON KY
1229 AM EST WED NOV 26 2014 .UPDATE... ISSUED AT 1136 PM EST TUE NOV 25 2014 DID AN UPDATED MAINLY TO FRESHEN UP THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. ALSO INCREASED THE SKY COVER SLIGHTLY IN THE FAR NORTHERN COUNTIES OF THE CWA...BASED ON THE LATEST SATELLITE RETURNS. CONTINUE TO AGREE WITH PREVIOUS UPDATE AS FAR AS SNOWFALL TOTALS. THE LATEST NAM12 SEEMS TO HAVE COME IN WITH SLIGHTLY LESS PRECIP THAN THAT OF THE 18Z RUN...WHICH SEEMS TO ACTUALLY MAKE MORE SENSE GIVEN THE STRONG UPTICK IN MOISTURE AT 18Z /SEEMS TO HAVE BEEN A LITTLE ERRONEOUS/. EVEN MORE CONFUSING IS THE LATEST HRRR RUN WHICH IS STILL ONLY BRINGING PRECIP INTO PIKE AND LETCHER COUNTIES OVERNIGHT...WHILE THE REMAINDER OF THE CWA REMAINS DRY. THIS SEEMS A BIT EXTREME AS WELL IN COMPARISON TO THE 6 HOURS MODELS. GIVEN ALL THE UNCERTAINTY...ENDED UP JUST KEEPING SNOW TOTALS THE SAME. ONCE PRECIP MOVES INTO THE REGION...THIS WILL BE THE TIME TO ASSESS THE CURRENT CONDITIONS COMPARED TO THAT OF THE MODEL RUNS...AND ADJUST AMOUNTS /QFP AND SNOW/ UP OR DOWN AS NEEDED. FORECASTED TEMPERATURES ARE ALREADY FAIRLY CLOSE TO THE FREEZING LINE. ANY SHIFT A COUPLE DIRECTIONS ONE WAY OR ANOTHER COULD MEAN THE DIFFERENCE BETWEEN MORE OR LESS SNOW IN A PARTICULAR LOCATION. UPDATE ISSUED AT 725 PM EST TUE NOV 25 2014 DID AN UPDATED MAINLY TO FRESHEN UP THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. ALSO BUMPED UP THE SKY COVER QUICKER THROUGH THE EVENING AS HIGH CLOUDS HAVE SPREAD IN QUICKLY FROM THE SOUTHWEST. THE 18Z RUNS HAVE COME IN WITH BEEFIER THOUGHTS ON SNOW AS BOTH THE GFS AND NAM12 TAKE THE PCPN FURTHER WEST. THE GFS SEEMS TOO WARM AT THE SFC FOR MUCH SNOW OR ACCUMULATION FOR LOCATIONS OUTSIDE OF OUR CURRENT ADVISORY WITH ITS LATEST RUN. THE NAM12...ON THE OTHER HAND...APPEARS TO GO OVERBOARD ON THE QPF AND THEREFORE SNOW OVER OUR EASTERN COUNTIES. THERE REMAINS PLENTY OF FACTORS THAT WOULD HAMPER THIS OCCURRENCE WITH CONVECTION TO THE SOUTH CUTTING OFF SOME OF THE BEST MOISTURE FROM BEING TRANSPORTED INTO KENTUCKY AS CLEANLY AS ENVISIONED BY THE OFF SYNOPTIC TIME RUN. NEVERTHELESS WILL BE MONITORING THE RADAR TRENDS AND NEAR TERM MODELS FOR SIGNS THAT THE CURRENT FORECAST REMAINS ON TRACK. TO THAT THOUGHT...THE LATEST HRRR RUNS HAVE TRENDED ITS PCPN SHIELD FURTHER TO THE NORTHWEST BUT STILL A FAR CRY FROM THE 6 HOURLY MODELS. THE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 325 PM EST TUE NOV 25 2014 ...ACCUMULATING SNOW EXPECTED OVER FAR EASTERN KENTUCKY TONIGHT INTO WEDNESDAY MORNING... 19Z SFC ANALYSIS SHOWS HIGH PRESSURE STILL INFLUENCING THE WEATHER OF EASTERN KENTUCKY. THIS HAS PROVIDED PLENTY OF SUNSHINE AND GENERALLY SOUTHWEST WINDS OF 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THESE CONDITIONS...ALONG WITH GOOD DRYING THROUGH EARLY AFTERNOON HAS SENT TEMPERATURES WELL UP INTO THE 50S FOR MOST OF THE AREA...THOUGH LOCATIONS NORTHWEST OF INTERSTATE 64 ARE LAGGING IN THE UPPER 40S. OF NOTE ON THE SFC CHART IS AN AREA OF DEVELOPING LOW PRESSURE CROSSING NORTHERN FLORIDA ON ITS WAY TO THE SOUTHEAST U.S. SEABOARD. THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE FIRST PART OF THE SHORT TERM FORECAST. THEY ALL TAKE A STRONG SHORTWAVE CURRENTLY BOTTOMING OUT OVER THE CENTRAL GULF COAST NORTHEAST INTO THE SOUTHERN APPALACHIANS BY WEDNESDAY MORNING. IN ADDITION...A COMPACT WAVE WILL BE DROPPING SOUTHEAST FROM THE NORTHERN PLAINS INTO THE MID MISSISSIPPI VALLEY AND EVENTUALLY THROUGH THE TENNESSEE VALLEY LATER WEDNESDAY NIGHT. THE MODELS ARE CLOSE ON THE TIMING OF THIS BUT THE CORE OF THE ENERGY IS FURTHER SOUTH IN THE NAM... ECMWF...AND GEM WHEN COMPARED TO THE GFS. WILL FAVOR THIS MORE SOUTHERN TRACK AS SEEN IN THE CONSENSUS. IN GENERAL HAVE LEANED MOST CLOSELY TO THE HIGHER RESOLUTION MODELS OF THE NAM12 AND HRRR... THOUGH THE HRRR PCPN FIELDS SEEM TOO FAR SOUTHEAST AND SLOW LATER TONIGHT. SENSIBLE WEATHER WILL FEATURE A QUICK INCREASE IN CLOUD COVER FROM THE SOUTHEAST AS THE COASTAL LOW STARTS TO TAKE SHAPE LATER THIS EVENING. LOWER CLOUDS AND PCPN WILL START TO SPILL OVER THE SPINE OF THE APPALACHIANS AND MOVE INTO OUR FAR EASTERN COUNTIES AROUND MIDNIGHT. EXPECT TEMPERATURES TO WET BULB DOWN WHEN THE PCPN MOVES IN AND TRANSITION THE RAIN TO SNOW IN THE HIGHER ELEVATIONS FIRST BUT EVENTUALLY DOWN IN THE VALLEYS...AS WELL. THE HEAVIEST SNOW WILL FALL IN THE HIGHER TERRAIN ALONG THE VIRGINIA BORDER WHERE AS MUCH AS A QUARTER TO A THIRD OF AN INCH OF LIQUID WILL LIKELY OCCUR. THIS WILL PROBABLY AMOUNT TO BETWEEN TWO AND THREE INCHES OF WET SNOW IN THE HIGHER TERRAIN...ABOVE 2000 FEET AND AROUND AN INCH OR LESS ELSEWHERE. HIGHER RIDGES BELOW 2000 FEET CAN EXPECT TO PICK UP BETWEEN ONE AND TWO INCHES BY MIDDAY WEDNESDAY. HAVE SET UP THIS AREA WITH A WINTER WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON WEDNESDAY FOR THIS PASSING EVENT. WITH THE POTENTIAL FOR LIGHT ACCUMULATIONS IN THE COUNTIES IMMEDIATELY WEST OF THE ADVISORY WILL ALSO ISSUE AN SPS ADDRESSING THIS MARGINAL CONCERN. OTHERWISE...THE COASTAL PULLS OUT LATER WEDNESDAY WITH A BRIEF VISIT BY HIGH PRESSURE FOR EAST KENTUCKY IN ITS WAKE. HOWEVER...THE NEXT DEVELOPING LOW WORKS IN FROM THE NORTHWEST LATER THAT NIGHT CARVING ITS WAY THROUGH OUR SOUTHERN COUNTIES INTO DAWN THURSDAY. THIS TOO WILL BRING SOME RAIN OR SNOW TO PARTS OF THE AREA WITH SOME SLUSHY LIGHT SNOW ACCUMULATIONS POSSIBLE MAINLY ON RIDGES AND GRASSY/ELEVATED SURFACES. AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME MORE SIGNIFICANT TERRAIN BASED ADJUSTMENTS TONIGHT INTO WEDNESDAY IN THE EXPECTED SNOW AREAS OF THE FAR EAST. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE MAV AND MET NUMBERS THROUGH THE PERIOD. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 354 PM EST TUE NOV 25 2014 SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH AND ASSOCIATED LOW PRESSURE WILL BE MOVING EAST OF THE REGION WITH BEST POP CHANCES ACROSS THE SE PORTIONS OF THE CWA. THIS WILL GENERALLY BE LIGHT RAIN/SNOW SHOWERS AND DO NOT EXPECT MUCH QPF THROUGH THE DAY THURSDAY AT THIS POINT. THIS SYSTEM SLIDES EAST ALLOWING FOR NW/W FLOW TO SETUP ACROSS THE REGION AND THEREFORE HELD SLIGHT CHANCE IN FAR SE INTO THE AFTERNOON. SURFACE HIGH PRESSURE WILL SLOWLY SLIDE EAST THROUGH THE NIGHT THURSDAY AND GENERALLY CRESTING ACROSS THE REGION EARLY FRIDAY. THIS HIGH PRESSURE BUILDS EAST BRINGING RETURN SOUTHERLY FLOW TO EASTERN KY WITH TEMPERATURES RISING INTO THE LOWER 50S SATURDAY. SATURDAY AFTERNOON WE DO PRESENT SOME SLIGHT CHANCE SHOWERS ESPECIALLY ACROSS THE FAR NORTH AS FRONTAL BOUNDARY GENERALLY STALLS ACROSS THE NORTH. THIS QUASI-STATIONARY FRONT WILL KEEP THE WEATHER UNSETTLED THROUGH THE PERIOD. THE QUESTION REALLY BECOMES HOW QUICKLY DOES THIS BOUNDARY MOVE SOUTH...THAT SAID THE 12Z ECMWF IS MORE PROGRESSIVE MOVING THIS FRONT SOUTH THAN THE 12Z GFS. RIGHT NOW WITH MODEL DISCREPANCIES WILL KEEP BLEND POPS FOR THE MOST PART BUT WOULD THINK THESE POPS WILL CONTINUE TO TREND UP ONCE MODELS COME INTO BETTER ALIGNMENT. SATURDAY HIGHS ARE EXPECTED TO WARM INTO THE LOW TO MID 50S WITH TEMPERATURES MODIFYING INTO THE UPPER 50S TO LOWER 60S THROUGH THE PERIOD. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1228 AM EST WED NOV 26 2014 VFR CONDITIONS WILL CONTINUE AT THE TAF SITES THROUGH AROUND 7Z. AFTER THAT THE AIRPORTS WILL BEGIN TO EXPERIENCES MVFR CIGS AS LOW LEVEL CLOUD AND PRECIPITATION BEGIN OVERSPREADING THE AREA. RAIN AND SNOW WILL BE POSSIBLE INITIALLY...BEFORE COLDER AIR MOVES IN ALOFT AND CHANGES ALL PRECIPITATION OVER TO SNOW. THE SNOW SHOULD BE FAIRLY LIGHT AT JKL AND SJS. ONCE THE SNOW BEGINS...SOME FOG MAY ALSO FORM AT JKL AND SJS. THE COMBINATION OF BOTH PHENOMENA COULD LEAD TO BRIEF PERIODS OF IFR OR EVEN LIFR CONDITIONS AT BOTH AIRPORTS. LOZ WILL BE ON THE FURTHERS WESTERN EXTEND OF ANY PRECIPITATION...AND SHOULD SEE MAINLY MVFR CONDITIONS AT WORST IN WHATEVER PRECIPITATION IS ABLE TO AFFECT THAT AIRPORT. AT THIS TIME...SME LOOKS TO BE IN THE CLEAR AS FAR AS PRECIPITATION IS CONCERNED...BUT COULD EXPERIENCE SOME BRIEF PERIODS OF MVFR FOG...ALSO THIS A LOW CONFIDENCE FORECAST. THE PRECIPITATION SHOULD BE ENDING AT THE AFFECTED AIRPORTS BETWEEN 11 AND 13Z...WITH VFR CONDITIONS EXPECTED THE REST OF THE PERIOD. CLOUD COVER WILL BE PERSISTENT THROUGHOUT THE DAY TODAY...WITH BROKEN TO OVERCAST COVERAGE EXPECTED EVEN AFTER THE PRECIPITATION ENDS. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR KYZ087-088-110- 113-115-117>120. && $$ UPDATE...JMW SHORT TERM...GREIF LONG TERM...DJ AVIATION...AR
AREA FORECAST DISCUSSION
NWS JACKSON KY
1137 PM EST TUE NOV 25 2014 .UPDATE... ISSUED AT 1136 PM EST TUE NOV 25 2014 DID AN UPDATED MAINLY TO FRESHEN UP THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. ALSO INCREASED THE SKY COVER SLIGHTLY IN THE FAR NORTHERN COUNTIES OF THE CWA...BASED ON THE LATEST SATELLITE RETURNS. CONTINUE TO AGREE WITH PREVIOUS UPDATE AS FAR AS SNOWFALL TOTALS. THE LATEST NAM12 SEEMS TO HAVE COME IN WITH SLIGHTLY LESS PRECIP THAN THAT OF THE 18Z RUN...WHICH SEEMS TO ACTUALLY MAKE MORE SENSE GIVEN THE STRONG UPTICK IN MOISTURE AT 18Z /SEEMS TO HAVE BEEN A LITTLE ERRONEOUS/. EVEN MORE CONFUSING IS THE LATEST HRRR RUN WHICH IS STILL ONLY BRINGING PRECIP INTO PIKE AND LETCHER COUNTIES OVERNIGHT...WHILE THE REMAINDER OF THE CWA REMAINS DRY. THIS SEEMS A BIT EXTREME AS WELL IN COMPARISON TO THE 6 HOURS MODELS. GIVEN ALL THE UNCERTAINTY...ENDED UP JUST KEEPING SNOW TOTALS THE SAME. ONCE PRECIP MOVES INTO THE REGION...THIS WILL BE THE TIME TO ASSESS THE CURRENT CONDITIONS COMPARED TO THAT OF THE MODEL RUNS...AND ADJUST AMOUNTS /QFP AND SNOW/ UP OR DOWN AS NEEDED. FORECASTED TEMPERATURES ARE ALREADY FAIRLY CLOSE TO THE FREEZING LINE. ANY SHIFT A COUPLE DIRECTIONS ONE WAY OR ANOTHER COULD MEAN THE DIFFERENCE BETWEEN MORE OR LESS SNOW IN A PARTICULAR LOCATION. UPDATE ISSUED AT 725 PM EST TUE NOV 25 2014 DID AN UPDATED MAINLY TO FRESHEN UP THE T AND TD GRIDS PER THE LATEST OBS AND TRENDS. ALSO BUMPED UP THE SKY COVER QUICKER THROUGH THE EVENING AS HIGH CLOUDS HAVE SPREAD IN QUICKLY FROM THE SOUTHWEST. THE 18Z RUNS HAVE COME IN WITH BEEFIER THOUGHTS ON SNOW AS BOTH THE GFS AND NAM12 TAKE THE PCPN FURTHER WEST. THE GFS SEEMS TOO WARM AT THE SFC FOR MUCH SNOW OR ACCUMULATION FOR LOCATIONS OUTSIDE OF OUR CURRENT ADVISORY WITH ITS LATEST RUN. THE NAM12...ON THE OTHER HAND...APPEARS TO GO OVERBOARD ON THE QPF AND THEREFORE SNOW OVER OUR EASTERN COUNTIES. THERE REMAINS PLENTY OF FACTORS THAT WOULD HAMPER THIS OCCURRENCE WITH CONVECTION TO THE SOUTH CUTTING OFF SOME OF THE BEST MOISTURE FROM BEING TRANSPORTED INTO KENTUCKY AS CLEANLY AS ENVISIONED BY THE OFF SYNOPTIC TIME RUN. NEVERTHELESS WILL BE MONITORING THE RADAR TRENDS AND NEAR TERM MODELS FOR SIGNS THAT THE CURRENT FORECAST REMAINS ON TRACK. TO THAT THOUGHT...THE LATEST HRRR RUNS HAVE TRENDED ITS PCPN SHIELD FURTHER TO THE NORTHWEST BUT STILL A FAR CRY FROM THE 6 HOURLY MODELS. THE UPDATED GRIDS HAVE BEEN SENT TO THE NDFD AND WEB SERVERS. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 325 PM EST TUE NOV 25 2014 ...ACCUMULATING SNOW EXPECTED OVER FAR EASTERN KENTUCKY TONIGHT INTO WEDNESDAY MORNING... 19Z SFC ANALYSIS SHOWS HIGH PRESSURE STILL INFLUENCING THE WEATHER OF EASTERN KENTUCKY. THIS HAS PROVIDED PLENTY OF SUNSHINE AND GENERALLY SOUTHWEST WINDS OF 5 TO 10 KTS WITH OCCASIONAL GUSTS TO 15 KTS. THESE CONDITIONS...ALONG WITH GOOD DRYING THROUGH EARLY AFTERNOON HAS SENT TEMPERATURES WELL UP INTO THE 50S FOR MOST OF THE AREA...THOUGH LOCATIONS NORTHWEST OF INTERSTATE 64 ARE LAGGING IN THE UPPER 40S. OF NOTE ON THE SFC CHART IS AN AREA OF DEVELOPING LOW PRESSURE CROSSING NORTHERN FLORIDA ON ITS WAY TO THE SOUTHEAST U.S. SEABOARD. THE MODELS ARE IN PRETTY GOOD AGREEMENT ALOFT THROUGH THE FIRST PART OF THE SHORT TERM FORECAST. THEY ALL TAKE A STRONG SHORTWAVE CURRENTLY BOTTOMING OUT OVER THE CENTRAL GULF COAST NORTHEAST INTO THE SOUTHERN APPALACHIANS BY WEDNESDAY MORNING. IN ADDITION...A COMPACT WAVE WILL BE DROPPING SOUTHEAST FROM THE NORTHERN PLAINS INTO THE MID MISSISSIPPI VALLEY AND EVENTUALLY THROUGH THE TENNESSEE VALLEY LATER WEDNESDAY NIGHT. THE MODELS ARE CLOSE ON THE TIMING OF THIS BUT THE CORE OF THE ENERGY IS FURTHER SOUTH IN THE NAM... ECMWF...AND GEM WHEN COMPARED TO THE GFS. WILL FAVOR THIS MORE SOUTHERN TRACK AS SEEN IN THE CONSENSUS. IN GENERAL HAVE LEANED MOST CLOSELY TO THE HIGHER RESOLUTION MODELS OF THE NAM12 AND HRRR... THOUGH THE HRRR PCPN FIELDS SEEM TOO FAR SOUTHEAST AND SLOW LATER TONIGHT. SENSIBLE WEATHER WILL FEATURE A QUICK INCREASE IN CLOUD COVER FROM THE SOUTHEAST AS THE COASTAL LOW STARTS TO TAKE SHAPE LATER THIS EVENING. LOWER CLOUDS AND PCPN WILL START TO SPILL OVER THE SPINE OF THE APPALACHIANS AND MOVE INTO OUR FAR EASTERN COUNTIES AROUND MIDNIGHT. EXPECT TEMPERATURES TO WET BULB DOWN WHEN THE PCPN MOVES IN AND TRANSITION THE RAIN TO SNOW IN THE HIGHER ELEVATIONS FIRST BUT EVENTUALLY DOWN IN THE VALLEYS...AS WELL. THE HEAVIEST SNOW WILL FALL IN THE HIGHER TERRAIN ALONG THE VIRGINIA BORDER WHERE AS MUCH AS A QUARTER TO A THIRD OF AN INCH OF LIQUID WILL LIKELY OCCUR. THIS WILL PROBABLY AMOUNT TO BETWEEN TWO AND THREE INCHES OF WET SNOW IN THE HIGHER TERRAIN...ABOVE 2000 FEET AND AROUND AN INCH OR LESS ELSEWHERE. HIGHER RIDGES BELOW 2000 FEET CAN EXPECT TO PICK UP BETWEEN ONE AND TWO INCHES BY MIDDAY WEDNESDAY. HAVE SET UP THIS AREA WITH A WINTER WEATHER ADVISORY FROM MIDNIGHT THROUGH NOON WEDNESDAY FOR THIS PASSING EVENT. WITH THE POTENTIAL FOR LIGHT ACCUMULATIONS IN THE COUNTIES IMMEDIATELY WEST OF THE ADVISORY WILL ALSO ISSUE AN SPS ADDRESSING THIS MARGINAL CONCERN. OTHERWISE...THE COASTAL PULLS OUT LATER WEDNESDAY WITH A BRIEF VISIT BY HIGH PRESSURE FOR EAST KENTUCKY IN ITS WAKE. HOWEVER...THE NEXT DEVELOPING LOW WORKS IN FROM THE NORTHWEST LATER THAT NIGHT CARVING ITS WAY THROUGH OUR SOUTHERN COUNTIES INTO DAWN THURSDAY. THIS TOO WILL BRING SOME RAIN OR SNOW TO PARTS OF THE AREA WITH SOME SLUSHY LIGHT SNOW ACCUMULATIONS POSSIBLE MAINLY ON RIDGES AND GRASSY/ELEVATED SURFACES. AGAIN USED THE BCCONSSHORT AS A STARTING POINT FOR T/TD/WINDS THROUGH THE NEXT 24 HOURS AND THE SUPERBLEND THEREAFTER. DID MAKE SOME MORE SIGNIFICANT TERRAIN BASED ADJUSTMENTS TONIGHT INTO WEDNESDAY IN THE EXPECTED SNOW AREAS OF THE FAR EAST. AS FOR POPS...ENDED UP CLOSE TO A BLEND OF THE MAV AND MET NUMBERS THROUGH THE PERIOD. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 354 PM EST TUE NOV 25 2014 SHORTWAVE ENERGY ROUNDING THE BASE OF THE TROUGH AND ASSOCIATED LOW PRESSURE WILL BE MOVING EAST OF THE REGION WITH BEST POP CHANCES ACROSS THE SE PORTIONS OF THE CWA. THIS WILL GENERALLY BE LIGHT RAIN/SNOW SHOWERS AND DO NOT EXPECT MUCH QPF THROUGH THE DAY THURSDAY AT THIS POINT. THIS SYSTEM SLIDES EAST ALLOWING FOR NW/W FLOW TO SETUP ACROSS THE REGION AND THEREFORE HELD SLIGHT CHANCE IN FAR SE INTO THE AFTERNOON. SURFACE HIGH PRESSURE WILL SLOWLY SLIDE EAST THROUGH THE NIGHT THURSDAY AND GENERALLY CRESTING ACROSS THE REGION EARLY FRIDAY. THIS HIGH PRESSURE BUILDS EAST BRINGING RETURN SOUTHERLY FLOW TO EASTERN KY WITH TEMPERATURES RISING INTO THE LOWER 50S SATURDAY. SATURDAY AFTERNOON WE DO PRESENT SOME SLIGHT CHANCE SHOWERS ESPECIALLY ACROSS THE FAR NORTH AS FRONTAL BOUNDARY GENERALLY STALLS ACROSS THE NORTH. THIS QUASI-STATIONARY FRONT WILL KEEP THE WEATHER UNSETTLED THROUGH THE PERIOD. THE QUESTION REALLY BECOMES HOW QUICKLY DOES THIS BOUNDARY MOVE SOUTH...THAT SAID THE 12Z ECMWF IS MORE PROGRESSIVE MOVING THIS FRONT SOUTH THAN THE 12Z GFS. RIGHT NOW WITH MODEL DISCREPANCIES WILL KEEP BLEND POPS FOR THE MOST PART BUT WOULD THINK THESE POPS WILL CONTINUE TO TREND UP ONCE MODELS COME INTO BETTER ALIGNMENT. SATURDAY HIGHS ARE EXPECTED TO WARM INTO THE LOW TO MID 50S WITH TEMPERATURES MODIFYING INTO THE UPPER 50S TO LOWER 60S THROUGH THE PERIOD. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z WEDNESDAY EVENING) ISSUED AT 700 PM EST TUE NOV 25 2014 VFR CONDITIONS WILL CONTINUE THROUGH THE REST OF THE EVENING THOUGH CIGS WILL TAKE SHAPE AND START TO LOWER DOWN TO 10K FEET BY MIDNIGHT. A DEVELOPING LOW PRESSURE SYSTEM WILL SPREAD MOISTURE AND LOWER CLOUDS OVER EASTERN KENTUCKY LATER TONIGHT...WITH CIGS FALLING INTO THE MVFR RANGE IN THE EAST BY 08Z. IT STILL LOOKS LIKE WE SHOULD SEE A GRADIENT IN THOSE LOWER CIGS WITH THE LOWEST (IFR/MVFR) IN THE EAST...TRAILING BACK TO VFR IN THE WEST...THROUGH MID MORNING WEDNESDAY. WE WILL ALSO SEE PRECIPITATION SPREAD INTO THE AREA... MAINLY ACROSS SOUTHEASTERN KENTUCKY...AS A MIX OF RAIN AND SNOW...LIKELY BECOMING ALL SNOW IN THE PRE-DAWN HOURS. THIS SNOW WILL RESTRICT VISIBILITIES LATER TONIGHT AS WELL...PARTICULARLY AT KSJS WHERE VIS COULD BE BELOW A MILE AT TIMES IN THE HEAVIER SNOW BANDS. THE SNOW AND ANY RESTRICTIONS WILL END FOR THE TAF SITES FROM SOUTHWEST TO NORTHEAST DURING THE MORNING WEDNESDAY. WINDS WILL BE LIGHT AND VARIABLE THROUGH THE PERIOD. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL NOON EST WEDNESDAY FOR KYZ087-088- 110-113-115-117>120. && $$ UPDATE...JMW SHORT TERM...GREIF LONG TERM...DJ AVIATION...GREIF
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
117 AM EST WED NOV 26 2014 .SYNOPSIS... LOW PRESSURE SYSTEM IS EXPECTED TO DEVELOP AND RIDE NORTHWARD ALONG THE COAST ON WEDNESDAY...BRINGING ACCUMULATING SNOW TO AREAS SOUTH AND EAST OF PITTSBURGH. A SECOND WEAKER SYSTEM WILL USHER IN COLDER TEMPERATURES AND LINGERING SNOW SHOWER CHANCES THROUGH THE END OF THE WEEK. && .NEAR TERM /THROUGH TODAY/... THE 00Z KPBZ RAOB INDICATED A VAST DEPTH WITH DEWPOINT DEPRESSIONS THAT REVEALED A VERITABLE CHASM BETWEEN THE TEMPERATURE AND DEWPOINT CURVE IN THE VERTICAL. AS SUCH...A DEEP LAYER OF DRY AIR HAS MADE RESIDENCE OVER THE AREA...WHICH SHOULD ALLOW FOR THE VAST MAJORITY OF THE CWA TO REMAIN DRY THROUGH THE NIGHTTIME HOURS IN ADVANCE OF THE SYSTEM ADVANCING NORTHEASTWARD UP THE EASTERN SEABOARD. WHILE NO CHANGES WERE MADE TO THE FORECAST FOR TOMORROW AT THE MOMENT...AN EARLY LOOK AT 00Z CANADIAN/GFS/NAM AND 04Z HRRR RUNS DOES STILL REVEAL SOME RATHER CONCERNING CHARACTERISTICS WITH REGARD TO THE EVOLUTION OF THE OVERALL PATTERN...PRODUCTION OF PRECIPITATION FROM THE MODELS THEMSELVES...VAST DISCREPANCIES WITH WARM ADVECTION...TROUBLE WITH WET BULB PROCESSES...NOT TO MENTION THE MORE EVERYDAY ISSUES WITH THE TRACK OF THE LOW LEVEL CENTER OF THE SYSTEM...LOW LEVEL THERMAL FIELDS...AND QPF PLACEMENT. ALL OF THESE ISSUES WILL HAVE TO BE ADEQUATELY CHEWED THROUGH DURING THE REMAINDER OF THIS SHIFT...HOWEVER LATER START TIMES DO LOOK BETTER AT THE MOMENT. AND IT SEEMS FAIRLY CLEAR THAT THE BEST WINDOW FOR ACCUMULATING SNOW WILL BE RATHER SHORT...AS IN REALLY NOT MUCH LONGER THAN 6 HOURS ANYWHERE...AND LIKELY ONLY MAYBE 2-3 HOURS IN PITTSBURGH ITSELF. COMBINING THAT WITH THE SYSTEM MOVING THROUGH DURING THE DAYTIME WITH WARM GROUND TEMPERATURES AND MARGINAL BOUNDARY LAYER TEMPERATURES...AND IT SEEMS CLEAR THAT WITHOUT INTENSE SNOW RATES...ACCUMULATIONS OUTSIDE THE RIDGES MAY BE TOUGH. THAT SAID...TEMPERATURES BASED UPON CURRENT TRENDS AND WET BULB PROFILES MAY WELL START OUT THE DAY TOMORROW A BIT LOWER THAN PREVIOUSLY FORECAST. ALL OF THIS WILL NEED TO BE MULLED INTO THE FULL UPDATE OF THE FORECAST FOR TODAY A BIT LATER THIS MORNING. FRIES && .SHORT TERM /TONIGHT THROUGH FRIDAY/... ANY LINGERING SNOW IN THE FAR EAST THIS EVENING WILL END QUICKLY AS THE LIFT AND MOISTURE HEAD TOWARD THE COAST WITH THE EXITING LOW. HUGE DRY SLOT WILL OVERTAKE THE ENTIRE AREA THIS EVENING AND MIXING HEIGHTS WILL BE WELL BELOW THE DENDRITIC GROWTH ZONE... ENDING THE ATMOSPHERES ABILITY TO CREATE SNOW. CAA WILL BE GOING ALL NIGHT...BUT WITH THE LACK OF DEEP MOISTURE AND A RATHER WEAK AND UNORGANIZED FLOW ALOFT...DO NOT EXPECT ANY SNOW SHOWERS TO REDEVELOP. FOR THE MOST PART...THURSDAY MORNING LOOKS DRY AS THE FLOW ALOFT REMAINS UNORGANIZED AND MIXING HEIGHTS ARE JUST TOO LOW TO REACH INTO THE SNOW GROWTH ZONE. SHORTWAVE TROUGH WILL SWING THROUGH LATE THURSDAY...INCREASING LARGE SCALE ASCENSION AND BRINGING ANOTHER SHOT OF COLDER AIR THURSDAY NIGHT. WINDS ALOFT WILL INCREASE IN SPEED AND BECOME WEST-NORTHWESTERLY. THE SNOW GROWTH ZONE BEGINS TO LOWER AND LAKE ERIE WILL COME INTO PLAY. WILL BRING POPS BACK IN ACROSS THE NORTH AND RIDGES THURSDAY AFTERNOON. CAA CONTINUES THURSDAY NIGHT BEHIND EXITING SHORTWAVE TROUGH. FOR A TIME...WINDS ALOFT LOOK GOOD FOR LAKE INFLUENCES AND THE SNOW GROWTH ZONE WILL DROP INTO AN AREA OF HIGHER SATURATION. EXPECT AN INCREASE IN SNOW SHOWER COVERAGE THURSDAY NIGHT...WITH THE NORTH AND RIDGES THE MOST LIKELY LOCATIONS FOR ACCUMULATING SNOW. SURFACE HIGH WILL BUILD IN ON FRIDAY AND THE ENTIRE ATMOSPHERE WILL DRY OUT DURING THE MORNING HOURS. COULD SEE SOME LINGERING FLURRIES ACROSS THE NORTH AND RIDGES FRIDAY MORNING...BUT THESE TOO WILL END AS SUBSIDENCE AND THE DRIER AIR TAKES OVER. A COLD DAY FRIDAY WITH TEMPS WELL BELOW SEASONABLE LEVELS. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... MODELS COMING INTO GOOD AGREEMENT WITH ANOTHER WARM UP FOR THE WEEKEND. MODELS ARE STILL TRYING TO FIGURE OUT HOW MUCH PRECIP WILL DEVELOP SATURDAY NIGHT AND SUNDAY WITH PASSING WAVES IN THE ZONAL FLOW ALOFT. EXPECT MOST OF SATURDAY NIGHT TO BE DRY WITH A SHOWER POSSIBLE BY SUNDAY MORNING. LOOKING LIKE A BETTER CHANCE FOR SHOWERS SUNDAY...PARTICULARLY IN THE AFTERNOON...AHEAD OF AN APPROACHING COLD FRONT. AREA WILL DRY OUT MONDAY WITH ANOTHER COOL DOWN ON TUESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... VFR CONDITIONS SHOULD CONTINUE UNTIL DAWN AT MOST SITES. SNOW WILL ADVANCE NORTH-NORTHWESTWARD THROUGH THE MORNING HOURS AND AFFECT MOST SITES OTHER THAN KZZV IN THE EARLY AFTERNOON. SOME DETERIORATION TO IFR IS LIKELY GENERALLY EAST OF KPIT DURING THE HEAVIEST WINDOW OF SNOW...HOWEVER THE WINDOW FOR ACCUMULATION AT ALL SITES OTHER THAN KMGW SHOULD BE FAIRLY BRIEF. AS SNOW SHUTS OFF BY EVENING...ABUNDANT LOW LEVEL MOISTURE SHOULD ALLOW FOR STRATUS TO REMAIN A FIXTURE AT MOST SITES. FRIES OUTLOOK.../WEDNESDAY NIGHT THROUGH SUNDAY/... PERIODIC RSTRNS ARE PSBL THRU THE WKEND WITH SVRL FAST MOVG DISTURBANCES. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR MDZ001. OH...NONE. PA...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR PAZ074- 076. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR PAZ023- 073-075. WV...WINTER STORM WARNING UNTIL 6 PM EST THIS EVENING FOR WVZ023- 041. WINTER WEATHER ADVISORY UNTIL 6 PM EST THIS EVENING FOR WVZ021- 022. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
511 PM EST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 510 PM EST WED NOV 26 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS CONTINUE TO SHOW AN AMPLIFIED PATTERN ACROSS NAMERICA WITH A RIDGE ALONG/JUST OFF THE W COAST...A TROF EXTENDING FROM NCNTRL CANADA TO THE GULF OF MEXICO AND A RIDGE OVER THE WRN ATLANTIC. A SHORTWAVE TROF SWINGING SE THRU NRN ONTARIO/NRN MN IS PRODUCING SOME -SN FROM NW WI ACROSS WRN UPPER MI INTO NRN ONTARIO. AT THE SFC...SHARPENING TROF RUNS FROM NEAR KIWD TO JUST S OF KCMX AND THEN NE ACROSS ERN LAKE SUPERIOR. MDT TO HVY LAKE ENHANCED SNOW IS SPREADING INTO WRN UPPER MI IN ASSOCIATION WITH THE TROF. OFF TO THE NW...STRONG SFC HIGH PRES ACROSS MANITOBA/SASKATCHEWAN IS BUILDING S AND E INTO THE NRN PLAINS. PERIOD OF LAKE ENHANCED SNOW IS EXPECTED TONIGHT UNDER HEIGHT FALLS/DEEP LAYER QVECTOR CONVERGENCE WITH SHORTWAVE SWINGING ACROSS THE UPPER LAKES. BEST...MOST PERSISTENT LOW-LEVEL CONVERGENCE IS INDICATED OVER THE FAR W. SO...MOST SUSTAINED MDT TO AT TIMES HVY SNOW WILL OCCUR OVER THE FAR W FROM THE PORCUPINE MTNS TO KIWD. WITH DGZ FALLING INTO THE LOW-LEVELS WHERE UPWARD MOTION IS FOCUSED... EXPECT SNOW TO WATER RATIOS TO INCREASE INTO THE 20-30 TO 1 RANGE TONIGHT. A LITTLE CONCERNED THAT THE UPWARD MOTION IS ONLY DEPICTED IN THE LOWEST LEVELS THIS EVENING...SUGGESTING LITTLE OVERALL SYNOPTIC SUPPORT WITH PASSING SHORTWAVE. THIS MAY TEND TO LIMIT COVERAGE OF HVY SNOW TO ONLY THE AREAS WHERE LOW-LEVEL CONVERGENCE IS FOCUSED. AS IT STANDS NOW...SITUATION APPEARS TO BE A MARGINAL WARNING EVENT WITH WARNING THRESHOLDS ONLY POTENTIALLY BEING MET IN A FEW LOCALIZED AREAS (8 INCHES OR MORE IN 12HRS OR 12 OR MORE IN 24HRS). LARGE PORTIONS OF ONTONAGON/GOGEBIC COUNTIES WILL PROBABLY FALL IN THE 4 TO 7 INCH SNOWFALL RANGE. OF NOTE...THERE IS A FAIRLY CONSISTENT SIGNAL AMONG MOST OF THE HIGH RES MODEL GUIDANCE FOR THE HEAVIEST SNOW TO AFFECT LOCATIONS JUST W OF KIWD. WILL BE INTERESTING TO SEE IF THAT INDEED DOES HAPPEN. OVER THE KEWEENAW... SNOWFALL HAS NOT BEEN ESPECIALLY NOTEWORTHY WITH SFC TROF PASSAGE WHICH IS WHEN THE HEAVIEST SNOWFALL WOULD LIKELY OCCUR. WITH A DECENT LOW-LEVEL CONVERGENCE SIGNAL LACKING TONIGHT...CONSIDERED DROPPING ADVY...BUT WILL HOLD OFF FOR NOW WITH POTENTIAL FOR SNOW TO STILL PICK UP FOR A TIME THIS EVENING DURING THE PERIOD OF SYNOPTIC FORCING. TO THE E...LONGER FETCH/BETTER TERRAIN ENHANCEMENT WILL LEAD TO ANOTHER AREA OF HEAVIER SNOW DEVELOPING OVER NCNTRL UPPER MI SPREADING FROM BARAGA COUNTY/FAR NRN MARQUETTE COUNTY EARLY THIS EVENING TO ALGER COUNTY LATE EVENING. LOOKS LIKE SOLID ADVY AMOUNTS FROM THE HURON MTNS TO NEGAUNEE AND EAST INTO WRN ALGER COUNTY. POTENTIAL IS THERE FOR LOCALIZED WARNING AMOUNTS GIVEN THE INCREASING SNOW TO WATER RATIOS AND THE LIKLIHOOD OF A LAKE NIPIGON INITIATED DOMINANT BAND LATER TONIGHT INTO THE MORNING HRS THAT WOULD LIKELY IMPACT LOCATIONS SOMEWHERE FROM AROUND BIG BAY/MARQUETTE TO AROUND THE SHOT POINT AREA. IF SUCH A BAND DOES DEVELOP AND BECOME STATIONARY FOR SEVERAL HRS...WARNING AMOUNTS MAY BE ACHIEVED. BLSN WILL ALSO BE AN ISSUE IN THE OPEN AREAS ALONG LAKE SUPERIOR WHERE WINDS WILL GUST OVER 30 MPH. WHILE THERE MAY BE A BRIEF PERIOD OF HEAVIER SNOW OVER LUCE COUNTY WITH TROF PASSAGE... SETUP AFTER TROF PASSAGE IS NOT FAVORABLE FOR ADVY SNOWFALL AMOUNTS IN THAT AREA. ACROSS THE REST OF THE AREA...EXPECT SOME -SN FOR A TIME TONIGHT. SOME OF THE LES OFF LAKE SUPERIOR WILL REACH NRN DELTA AND SRN SCHOOLCRAFT COUNTIES TO PROVIDE AN INCH OR TWO OF SNOWFALL. ON THANKSGIVING DAY...FCST SOUNDINGS SHOW INVERSIONS AT A LOW 4KFT TO START THE DAY. LOW-LEVEL FLOW TRENDS ANTICYCLONIC DURING THE DAY...ESPECIALLY SO OVER WRN LAKE SUPERIOR AS SFC HIGH PRES RIDGE WILL EXTEND FROM THE MID MISSISSIPPI VALLEY N THRU WRN UPPER MI/WRN LAKE SUPERIOR BY 00Z FRI. THESE 2 FACTORS COMBINED WITH RISING HEIGHTS/LARGE SCALE SUBSIDENCE/QVECTOR DIVERGENCE WILL LIMIT LES INTENSITY AND WILL RESULT IN LES DIMINISHING FROM W TO E THRU THE DAY. IN FACT OVER THE FAR W...LES WILL END LATE IN THE AFTN AROUND KIWD AS FLOW BACKS SW. THE ONE POSTIVE FACTOR FOR THE LES ON THANKSGIVING DAY IS THAT THE DGZ WILL OCCUPY MOST OF THE CONVECTIVE LAYER TO FLUFF UP SNOW ACCUMULATIONS. SO...DESPITE THE NEGATIVES LEADING TO MOSTLY LIGHT LES ON THE WHOLE...MIGHT BE ABLE TO FLUFF UP 3-4 INCHES OF SNOW WHERE LES IS MOST PERSISTENT. THE GREATEST ACCUMULATIONS WILL OCCUR E OF MARQUETTE WHERE LOW-LEVEL FLOW IS MORE CYCLONIC THRU THE EARLY PART OF THE DAY AND WHERE LAKE NIPIGON PRECONDITIONING WILL COME INTO PLAY. AWAY FROM THE MAIN LES... SCT -SHSN/FLURRIES ARE POSSIBLE AT TIMES...EXCEPT OVER THE FAR SCNTRL. TEMPS WILL BE UNSEASONABLY COLD ON THANKSGIVING DAY AS 850MB THERMAL TROF (AROUND -20C) PASSES ACROSS THE AREA. EXPECT HIGHS MOSTLY IN THE LOW/MID TEENS...TO AROUND 20F ALONG LAKE SUPERIOR AND E. RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL FALL. IF TEMP DOESN`T REACH 14F...IT WILL BE THE COLDEST MAX TEMP FOR SO EARLY IN THE SEASON. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 342 PM EST WED NOV 26 2014 THU NIGHT...THE LINGERING LES WILL DIMINISH AS THE SFC RIDGE AXIS SLIDES THROUGH THE WRN LAKES AND LOW LEVEL WINDS BACK TO THE SW. WITH LIGHT WINDS AND A PERIOD OF CLEARING OVER THE INTERIOR WEST DURING THE EVENING...TEMPS WILL DROP QUICKLY TO MINS BELOW GUIDANCE BEFORE RECOVERING OVERNIGHT AS CLOUDS MOVE IN. MODELS WERE CONSISTENT IN BRINGING POTENTIAL FOR SOME LIGHT SNOW INTO THE WEST LATE WITH THE DEVELOPING WAA PATTERN. FRI...SNOW IS EXPECTED TO SPREAD ACROSS THE REGION WITH FAVORABLE MOISTURE ADVECTION AND ISENTROPIC LIFT THROUGH THE 850-700 MB FRONTAL ZONE. 3 G/KG MOISTURE AVAILABLE IN THE 285K-295K LAYER DURING THE PERIOD OF STRONGEST LIFT IS CONSISTENT WITH POTENTIAL FOR 2 TO 4 INCHES OF SNOW WITH MODELS CONSENSUS QPF OF 0.10 TO 0.20 INCHES AND SLR VALUES FROM AROUND 15/1-20/1. THERE IS STILL SOME UNCERTAINTY WHERE THE BAND OF HEAVIER SNOW WILL DEVELOP AS THE 12Z NAM BRINGS GREATER AMOUNTS OF PCPN INTO SRN UPPER MI COMPARED TO THE GFS AND ECMWF. THERE WILL ALSO BE THE POTENTIAL FOR A BAND OF LAKE ENHANCED SNOW OFF OF LAKE MI THAT COULD SPREAD EASTWARD FROM NEAR THE GARDEN PENINSULA INTO LUCE COUNTY. SINCE THE STRONGEST LOW LEVEL CONV IS EXPECTED TO MOVE STEADILY TO THE EAST...SNOW AMOUNTS IN ANY ONE LOCATION SHOULD BE LIMITED. HOWEVER...CONFIDENCE IS LOWER FOR THE POSITION/STRENGTH OF THIS FEATURE THAT COULD ADD SEVERAL INCHES TO THE SNOW TOTALS. FRI NIGHT INTO SAT...SFC LOW PRES IS FCST TO SPREAD FROM THE NRN PLAINS TO THE UPPER MS VALLEY WITH CONTINUED WAA BRINGING SUBSTANTIAL 850 MB WARMING. NAM/GFS 285-295K ISENTROPIC PROGS SUGGEST THAT THE STRONGEST LIFT AND DEEPEST MOISTURE WILL REMAIN ACROSS LAKE SUPERIOR AND FAR NRN UPPER MI. WITH A PROMINENT 850-700 MB DRY LAYER DEVELOPING TO THE SOUTH...FREEZING DRIZZLE WILL BE POSSIBLE ALONG WITH SOME LIGHT SNOW OR FLURRIES AS ICE NUCLEI BECOME MORE SCARCE. ANY PCPN AMOUNTS ARE EXPECTED TO BE LIGHT WITH ONLY A FEW HUNDREDTHS OF AN INCH AT MOST. THERE MAY ALSO BE ENOUGH 900-700 MB WARMING INTO THE AREA OF DEEPER MOISTURE FOR SOME FZRA. SAT NIGHT AND SUN...LOW PRES LIFTING NE TOWARD JAMES BAY SAT NIGHT WILL DRAG A COLD FRONT THROUGH THE NRN LAKES WITH MUCH COLDER AIR MOVING IN ON NW WINDS. WITH 850 MB TEMPS FALLING TO NEAR -18C...LES WILL BE LIKELY FOR NW WIND SNOW BELTS. A LIMITING FACTOR FOR HEAVIER SNOW WILL BE SUBSTANTIAL 850-700 MB DRYING WITH BACKING AND INCREASING ACYC LOW LEVEL WINDS FROM LATE SUN INTO SUN NIGHT. MON-WED...THE GFS/GEFS AND ECMWF WERE IN REASONABLE AGREEMENT WITH THE PATTERN INTO NEXT WEEK WITH HIGH PRES BUILDING INTO THE REGION MON INTO MON NIGHT BRINGING DIMINISHING LES. ANOTHER MID LEVEL AND SFC TROUGH MOVING THROUGH TUE INTO TUE NIGHT COULD BRING SOME LIGHT SNOW TO THE AREA. THE MODELS HAVE TRENDED TOWARD KEEPING COLDER ACROSS REGION THAT WOULD KEEP ANY PCPN AS SNOW WITH MAX TEMPS RECOVERING INTO THE MID 20S TO AROUND 30 BY TUE AND WED. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1245 PM EST WED NOV 26 2014 DISTURBANCE AND ASSOCIATED SFC TROF WILL SWING ACROSS UPPER MI THIS AFTN/EVENING. INCREASING LAKE ENHANCED SNOW WILL AFFECT ALL TERMINALS AS THE TROF PUSHES ACROSS THE AREA...BEGINNING LATEST AT KSAW. AT KIWD/KCMX...IFR CONDITIONS ARE EXPECTED TO BECOME THE PREVAILING CONDITION THIS AFTN...THOUGH SOME LIFR WILL OCCUR AS WELL. WIND FLOW THIS EVENING WILL FAVOR KIWD FOR HEAVIEST SNOW/LOWEST CONDITIONS...AND LIFR WILL LIKELY PREVAIL THERE THIS EVENING WHILE KCMX REMAINS IFR. LOWERING INVERSION/DRYING AIR MASS WILL RESULT IN DIMINISHING LAKE EFFECT SNOW LATER IN THE PERIOD... ALLOWING IMPOVEMENT TO VFR. AT KSAW...VFR CONDITIONS WILL PREVAIL THIS AFTN. WITH TROF PASSAGE...EXPECT CONDITIONS TO FALL TO IFR LATE THIS EVENING ALONG WITH PERIODS OF LIFR. AS WINDS BEGIN TO BACK LATE TONIGHT AND ESPECIALLY THU MORNING...LAKE EFFECT SNOW WILL SHIFT MOSTLY E OF KSAW...ALLOWING IMPROVEMENT TO MVFR. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 348 PM EST WED NOV 26 2014 A SFC TROUGH WILL SLIDE SOUTH OVER LAKE SUPERIOR TONIGHT. BEHIND THE TROUGH...EXPECT NORTHERLY WINDS TO 30 KTS. WINDS WILL THEN DIMINISH TO UNDER 20 KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT NIGHT...EXPECT INCREASING S/SW WINDS TO 15-25KT FRI INTO SAT AHEAD OF FRONT. BEHIND THE FRONT...NW WINDS MAY REACH 20-30KT LATE SAT NIGHT AND SUN AND INCREASE TO GALES BY SUN NIGHT INTO MON. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST THURSDAY FOR MIZ006. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ004. LAKE EFFECT SNOW ADVISORY UNTIL 10 AM EST THURSDAY FOR MIZ005. LAKE EFFECT SNOW WARNING UNTIL 1 PM EST /NOON CST/ THURSDAY FOR MIZ002-009. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST THURSDAY FOR MIZ001-003. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...JLB AVIATION...ROLFSON MARINE...JLB
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
553 AM EST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 450 PM EST TUE NOV 25 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER NAMERICA WITH RIDGING ALONG/JUST OFF THE W COAST...A TROF EXTENDING FROM N OF HUDSON BAY TO TX AND A RIDGE JUST OFF THE EAST COAST. SHORTWAVE THAT PROVIDED WIDESPREAD SYNOPTIC SNOW AS WELL AS LAKE ENHANCED SNOW ACROSS THE FCST AREA LAST NIGHT HAS SHIFTED NE INTO QUEBEC. UPSTREAM...NEXT SHORTWAVE IS DIVING SE INTO THE DAKOTAS. A LESS DEFINED SHORTWAVE TROF IS FARTHER N OVER NRN PORTIONS OF MANITOBA/SASKATCHEWAN. DRYING AIR MASS...LOWERING INVERSION AND LOW LEVEL WINDS BECOMING MORE ANTICYCLONIC WITH SFC HIGH PRES THAT IS NOW NOSING INTO WRN UPPER MI HAVE RESULTED IN A STEADY DIMINISHING TREND/SHIFTING OF LINGERING LES THIS AFTN. IN FACT...OVER THE W...THERE MAY NOT BE MUCH MORE THAN SCT FLURRIES REMAINING. LAKE EFFECT CLOUD COVER IS ALSO DIMINISHING WITH CLR SKIES NOW BEING NOTED AROUND KIWD. TO THE W...CLOUDS IN ADVANCE OF AFOREMENTIONED SHORTWAVES ARE SLOWLY MOVING ACROSS NRN MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS TONIGHT...MIN TEMPS TONIGHT WITH A PROBABLE PERIOD OF CLR/PARTLY CLOUDY SKIES IN MANY AREAS AND THEN NEXT ROUND OF HEAVIER LES THAT WILL BEGIN TO ENTER THE PICTURE WED AFTN AS SHORTWAVE TROF SWINGS SE TOWARD THE UPPER LAKES. TONIGHT...ARRIVAL OF WEAK SFC HIGH PRES RIDGE COMBINED WITH STRENGTHENING LAND BREEZES WILL CONTINUE TO SHIFT LINGERING LES OFFSHORE. OVER THE E...SHIFTING LES SHOULD BE OFFSHORE NO LATER THAN AROUND MIDNIGHT. OVER THE W...ALTHOUGH THERE IS PROBABLY NOT MUCH MORE THAN FLURRIES CURRENTLY REMAINING...NOCTURNAL COOLING AND LAND BREEZE DEVELOPMENT RESULTING IN INCREASING CONVERGENCE SHOULD FAVOR SOME REDEVELOPMENT OF LES DURING THE NIGHT. AMONG THE HIGH RES MODELS...THERE IS DISAGREEMENT IN WHETHER SE MOVING SFC TROF WILL SINK FAR ENOUGH S TO KEEP LES OVER THE KEWEENAW. AT THIS POINT... BELIEVE SW FLOW ENHANCED BY LAND BREEZE WILL PUSH LES OFFSHORE...BUT THERE IS ENOUGH UNCERTAINTY TO MAINTAIN SOME SCT -SHSN WORDING OVER THE NRN PORTION OF THE KEWEENAW OVERNIGHT. AS FOR TEMPS...BASED ON SATELLITE IMAGERY...IT LOOKS LIKE THERE WILL BE A DECENT PERIOD OF CLEAR TO PARTLY CLOUDY SKIES TONIGHT OVER MUCH OF THE AREA. WITH LIGHT WINDS AND PRECIPITABLE WATER 40-55PCT OF NORMAL...FAVORED THE LOW END OF GUIDANCE. TEMPS SHOULD PLUMMET RAPIDLY THIS EVENING WHERE SKIES ARE CLEAR...AND EXPECT TRADITIONAL COLD SPOTS TO FALL TO AROUND -5F. HOWEVER...GIVEN THE SLOW ADVANCE OF UPSTREAM CLOUDS... CLOUDS MAY BE SLOWER TO ARRIVE THAN CURRENTLY FCST. COMBINED WITH FRESH SNOW COVER...COULD EASILY SEE TEMPS FALL TO -10F OR LWR IN THE USUAL COLD SPOTS. SHORTWAVE CURRENTLY MOVING INTO THE DAKOTAS WILL CONTINUE TO DROP SE TOWARD THE TENNESSEE VALLEY TONIGHT/WED AND WILL HAVE NO INFLUENCE HERE AS IT PASSES WELL S OF UPPER MI. OF CONCERN IS THE FOLLOWING SHORTWAVE TROF WHICH WILL SWING SE AND EXTEND FROM JAMES BAY TO MN BY 00Z THU. AS HEIGHT FALLS/MODEST DEEP LAYER FORCING PER QVECTORS OVERSPREAD THE RELATIVELY WARM WATERS OF LAKE SUPERIOR...SFC TROF MOVING OVER THE LAKE WILL SHARPEN UP...RESULTING IN INCREASING CONVERGENCE AND INTENSIFYING LAKE ENHANCED SNOW ALONG/NEAR TROF. EXPECT THIS TROF TO REACH THE KEWEENAW DURING THE MORNING AND THE W IN THE AFTN. TROF PROBABLY WON`T REACH NCNTRL UPPER MI UNTIL EVENING. NE ORIENTATION OF THE WINDS ACROSS THE KEWEENAW AFTER TROF PASSAGE WON`T BE ESPECIALLY FAVORABLE FOR PERSISTENT HEAVIER LAKE ENHANCED SNOW AFTER THE MAIN MDT/HVY SNOW BAND ALONG TROF SHIFTS S. FARTHER S...SHARPER LOW-LEVEL CONVERGENCE AND BETTER UPSLOPING IS EXPECTED INTO ONTONAGON/GOGEBIC COUNTIES...AND THIS IS INDICATED IN MODEL GUIDANCE IN LOW-LEVEL OMEGA FIELDS. WIND FLOW SUGGESTS LAKE NIPIGON PRECONDITONING WILL ALSO COME INTO PLAY OVER THE FAR W. WITH THESE FAVORABLE CONDITIONS CONTINUING INTO THE WED NIGHT...WILL HOIST A LAKE EFFECT SNOW ADVISORY FOR ONTONAGON/GOGEBIC STARTING AT 20Z WED. IN GENERAL...A QUICK COUPLE OF INCHES OF SNOW WILL PROBABLY OCCUR AS THE TROF MOVES ONSHORE OVER THE W. ELSEWHERE...SOME -SN SHOULD GRADUALLY OVERSPREAD THE REST OF WRN UPPER MI IN THE AFTN. TO THE E...IT APEARS WINDS WILL BACK SUFFICIENTLY TO BRING SOME LES OFF LAKE MICHIGAN INTO THE FAR ERN FCST AREA IN THE AFTN. WINDS ARE LIGHT/CONVERGENCE WEAK...SO NOT EXPECTING MUCH WITH THE LES OFF LAKE MI WED (LESS THAN 1 INCH). .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 553 AM EST WED NOV 26 2014 MODELS SHOW A FAIRLY PROGRESSIVE ZONAL FLOW PATTERN ACROSS THE NRN CONUS THROUGH MUCH OF THE EXTENDED PD WITH SERIES OF SHORTWAVES MOVING THROUGH THE AREA KEEPING WX FAIRLY ACTIVE THROUGH THE HOLIDAY WEEKEND. BEGINNING THANKSGIVING INTO THU NGT...MODELS INDICATE THE LLVL FLOW BACKING STEADILY AND BECOMING MORE ANTICYCLONIC THROUGH THANKSGIVING DAY WITH SFC HI PRES MOVING TOWARD CENTRAL IL LATE IN THE DAY UNDER HGT RISES/DNVA IN ADVANCE OF THE APPROACHING SHRTWV RDG FM THE NRN PLAINS. THE RESULT WL BE SHIFTING/DIMINISHING LES BANDS...ESPECIALLY OVER THE W HALF. THE SNOW SHOWERS SHOULD END COMPLETELY AT IWD LATE IN THE AFTN AS FLOW BACKS WSW. THE LES WL BE MORE PERSISTENT IN THE FAVORED SN BELTS E OF MARQUETTE WITH H85 THERMAL TROF/TEMPS AROUND -18C MOVING OVER ERN LAKE SUPERIOR LATE IN THE DAY...BUT INCREASING ANTICYCLONIC FLOW...WEAKENING LOW-LVL CONVERGENCE AND LOWERING OF INVERSION HGTS TO AROUND 3KFT AS SHOWN ON FCST SDNGS FROM INCREASED SUBSIDENCE AHEAD OF BUILDING RDG WL LIMIT ADDITIONAL SNOW ACUUMS TO GENERALLY NO MORE THAN 2-3". THANKSGIVING WL BE QUITE CHILLY WITH H85 THERMAL TROF PASSING OVERHEAD AND COULD FEATURE SOME RECORD LOW MAX TEMPS. CERTAINLY RECORD LOW MAX TEMP OF 18F HERE AT NWS MQT WILL BE IN JEOPARDY AS FCST TEMPS ARE IN THE MID TEENS. EXPECT THE LOWEST TEMPS OVER THE W HALF WHERE BACKING FLOW WL LIMIT LK SUPERIOR MODERATION. AS THE SFC RDG AXIS SHIFTS E ACROSS THE AREA AND THE FLOW BACKS TO THE W-SW...LINGERING LES OVER ERN COUNTIES WL SHIFT OUT INTO LK SUPERIOR ON THU NGT. TEMPS COULD FALL QUICKLY IN THE EVENING TOWARD THE LOWER END OF MODEL GUIDANCE BEFORE MORE HIGH CLDS OVERSPREAD THE AREA W-E ASSOCIATED WITH DEVELOPING SW FLOW/ISENTROPIC ASCENT IN ADVANCE OF A SHRTWV STREAKING EWD TOWARD MN. SINCE BOTH THE 00Z GFS AND NAM SHOW SN ASSOCIATED WITH THIS WAA/SHRTWV REACHING THE FAR W BY 12Z FRI...WL CONTINUE TO MAINTAIN SOME LOW CHC POPS IN THIS AREA LATE THU NGT. FRI/FRI NGT...SW FLOW/ISENTROPIC ASCENT OVER THE UPPER GREAT LAKES IN ADVANCE OF SHRTWV TRACKING EWD THRU MN IS PROGGED BY MOST OF THE MODELS TO BRING INCREASING MID LVL MSTR/WIDESPREAD SNOW TO THE FCST AREA ON FRI NE OF AN H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO MN AND WI. BEST ISENTROPIC ASCENT ON 280-290K SFCS ALONG WITH MIXR OF 3 G/KG MAY ALLOW FOR SOME MODERATE SNOW AMOUNTS APPROACHING ADVISORY CRITERIA OVER THE SCNTRL FCST AREA. WILL ALSO NEED TO MONITOR LAKE ENHANCED SNOW POTENTIAL OFF LAKE MI OVER THE ERN CWA AS SOME OF MODELS PARTICULARLY THE ECMWF SHOW LOW-LVL WINDS BECOMING MORE SRLY IN THE PRESENCE OF H85 TEMPS IN THE -8 TO -10C RANGE...SO WL MAINTAIN THE HIGHER POPS/QPF IN THIS AREA. ON FRI NGT...THE GFS AND NAM ARE ON THE QUICKER SIDE OF MODEL GUIDANCE SHOWING A STRONGER SHRTWV/SFC TROUGH REFLECTION TRACKING FASTER E ACROSS UPPER MI/LK SUPERIOR ON FRI NGT...ALLOWING FOR A COLDER WRLY FLOW ACROSS THE CWA FRI NGT. WILL FAVOR WPC PREFERRED SLOWER AND MORE CONSISTENT ECMWF SOLUTION WHICH SHOWS A SLOWER SFC LOW AND MORE AGGRESSIVE PUSH OF THE 850 MB WARM FRONT ACROSS THE CWA WITH H85 TEMPS RISING ABOVE 0C OVER THE WEST AND SCNTRL CWA BY 12Z SAT ACCOMPANIED BY DRY SLOTTING/LOWERING POPS FM THE SW. WITH ECWMF SNDGS CONTINUING TO SHOW LINGERING LLVL MSTR BLO THE WARMING/DRYING ARND H85...WILL CONTINUE TO CARRY MENTION OF FREEZING DZ OVER THE SW CWA. SAT/SAT NGT...SHRTWV EMBEDDED IN ZONAL FLOW OVER SRN CANADA WL STREAM E...WITH ACCOMPANYING SFC LOW STREAKING ENE THRU ONTARIO AND DRAGGING A COLD FRONT ACROSS THE CWA SAT AFTERNOON/SAT NIGHT. AHEAD OF THIS FRONT... MORE CONSISTENT AND FAVORED 12Z ECMWF/GEM-NH MODEL SOLNS SHOW WARM SURGE INTO THE UPR LKS WITH H85 TEMPS RISING AS HI AS 8-10C OVER THE SRN TIER ON SAT UNDER MID LVL DRYING. CONTINUE TO CARRY ONLY LOW CHC POPS OVER THE SRN TIER...WHERE THE ECMWF AND GEM-NH MODELS SHOW MORE AGGRESSIVE MID LVL DRYING FARTHER FM THE LOW TRACK. CONTINUED TO MENTION SOME FREEZING DZ IN THESE AREAS AS WELL. FARTHER TO THE N CLOSER TO THE LOW TRACK HAVE SOMEWHAT HIER CHC POPS AND INCLUDED MENTION OF FREEZING RA AND RA IN ADDITION TO SN IN CASE THE AIRMASS COOLS MORE DUE TO EVAPORATIVE COOLING. KEPT HIGH TEMPS IN THE LOWER TO MID 30S UNDER EXPECTED LOW CLOUDS. IT LOOKS LIKE ANY ICE ACCUMULATION WL BE MINOR DUE TO GENERAL DRYNESS OF AIRMASS. SUNDAY INTO TUESDAY...ECMWF AND GEM-NH SHOW MUCH COLDER AIR MOVING IN ON SUNDAY IN THE WAKE OF SAT NIGHT/S FRONT...WITH H85 TEMPS FCST AS LOW AS -17C WEST BY 00Z MON. EXPECT SOME LK EFFECT TO DEVELOP SUNDAY OVER THE NW FLOW AREAS BUT SINCE THE UPR FLOW WL REMAIN FAIRLY PROGRESSIVE...SFC HI PRES FM THE NRN PLAINS WL SHIFT THRU THE UPPER GREAT LAKES ON MON. THE RESULT SHOULD BE DIMINISHING LES ON MON WITH DRY AIRMASS LINGERING INTO TUE. WARMER SW FLOW ON THE WRN FLANK OF DEPARTING SFC HI PRES MAY DRAW ENOUGH MOISTURE N ON TUE AHEAD OF ANOTHER SHORTWAVE APPROACHING FM THE NRN PLAINS TO BRING A RETURN OF SOME LIGHT SNOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1256 AM EST WED NOV 26 2014 VFR CONDITIONS WILL CONTINUE AT KIWD/KSAW TONIGHT AND WILL CONTINUE AT KSAW THROUGH WED. NEXT APPROACHING DISTURBANCE WILL BRING SOME -SN/MVFR CONDITIONS TO KIWD BY WED AFTERNOON WHICH WILL FALL TO IFR LATE WED AFTERNOON LASTING INTO THE EVENING. AT KCMX...WINDS MAY RETAIN ENOUGH OVERWATER COMPONENT TO MAINTAIN MVFR CONDITIONS THRU MOST OF THE PERIOD. KSAW WILL FALL TO IFR CONDITIONS BY WED EVENING AS SNOW MOVES IN. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 450 PM EST TUE NOV 25 2014 PRES GRADIENT RAPIDLY WEAKENS TONIGHT WITH A WEAK SFC TROF DROPPING SE OVER LAKE SUPERIOR. THIS WILL RESULT IN WINDS DIMINISHING TO UNDER 20KT ACROSS THE LAKE. STRONG HIGH PRES WILL THEN BUILD SE INTO THE CANADIAN PRAIRIES WED AND INTO THE NRN PLAINS WED NIGHT. THIS WILL PUSH THE TROF SE AND TIGHTEN THE PRES GRADIENT. AS A RESULT... WITH THE TROF PASSAGE...EXPECT NORTHERLY WINDS TO RAMP UP TO 20-30KT FROM NW TO SE WED/WED NIGHT. NOT OUT OF THE QUESTION THAT THERE COULD BE SOME GALE FORCE GUSTS OVER THE CNTRL PORTION OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH TO UNDER 20KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT...EXPECT INCREASING WINDS TO 15-25KT FRI/FRI NIGHT AHEAD OF FRONT. BEHIND FRONT...NW WINDS MAY REACH 20-30KT LATE SAT/SUN. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST THURSDAY FOR MIZ006. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST THURSDAY FOR MIZ004. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR MIZ005. LAKE EFFECT SNOW WARNING FROM 3 PM EST /2 PM CST/ THIS AFTERNOON TO 1 PM EST /NOON CST/ THURSDAY FOR MIZ002-009. LAKE EFFECT SNOW ADVISORY FROM 3 PM THIS AFTERNOON TO 7 AM EST THURSDAY FOR MIZ001-003. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...VOSS AVIATION...JLA MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1258 AM EST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 450 PM EST TUE NOV 25 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW AN AMPLIFIED PATTERN OVER NAMERICA WITH RIDGING ALONG/JUST OFF THE W COAST...A TROF EXTENDING FROM N OF HUDSON BAY TO TX AND A RIDGE JUST OFF THE EAST COAST. SHORTWAVE THAT PROVIDED WIDESPREAD SYNOPTIC SNOW AS WELL AS LAKE ENHANCED SNOW ACROSS THE FCST AREA LAST NIGHT HAS SHIFTED NE INTO QUEBEC. UPSTREAM...NEXT SHORTWAVE IS DIVING SE INTO THE DAKOTAS. A LESS DEFINED SHORTWAVE TROF IS FARTHER N OVER NRN PORTIONS OF MANITOBA/SASKATCHEWAN. DRYING AIR MASS...LOWERING INVERSION AND LOW LEVEL WINDS BECOMING MORE ANTICYCLONIC WITH SFC HIGH PRES THAT IS NOW NOSING INTO WRN UPPER MI HAVE RESULTED IN A STEADY DIMINISHING TREND/SHIFTING OF LINGERING LES THIS AFTN. IN FACT...OVER THE W...THERE MAY NOT BE MUCH MORE THAN SCT FLURRIES REMAINING. LAKE EFFECT CLOUD COVER IS ALSO DIMINISHING WITH CLR SKIES NOW BEING NOTED AROUND KIWD. TO THE W...CLOUDS IN ADVANCE OF AFOREMENTIONED SHORTWAVES ARE SLOWLY MOVING ACROSS NRN MN. MAIN FCST CONCERNS IN THE SHORT TERM ARE LES TRENDS TONIGHT...MIN TEMPS TONIGHT WITH A PROBABLE PERIOD OF CLR/PARTLY CLOUDY SKIES IN MANY AREAS AND THEN NEXT ROUND OF HEAVIER LES THAT WILL BEGIN TO ENTER THE PICTURE WED AFTN AS SHORTWAVE TROF SWINGS SE TOWARD THE UPPER LAKES. TONIGHT...ARRIVAL OF WEAK SFC HIGH PRES RIDGE COMBINED WITH STRENGTHENING LAND BREEZES WILL CONTINUE TO SHIFT LINGERING LES OFFSHORE. OVER THE E...SHIFTING LES SHOULD BE OFFSHORE NO LATER THAN AROUND MIDNIGHT. OVER THE W...ALTHOUGH THERE IS PROBABLY NOT MUCH MORE THAN FLURRIES CURRENTLY REMAINING...NOCTURNAL COOLING AND LAND BREEZE DEVELOPMENT RESULTING IN INCREASING CONVERGENCE SHOULD FAVOR SOME REDEVELOPMENT OF LES DURING THE NIGHT. AMONG THE HIGH RES MODELS...THERE IS DISAGREEMENT IN WHETHER SE MOVING SFC TROF WILL SINK FAR ENOUGH S TO KEEP LES OVER THE KEWEENAW. AT THIS POINT... BELIEVE SW FLOW ENHANCED BY LAND BREEZE WILL PUSH LES OFFSHORE...BUT THERE IS ENOUGH UNCERTAINTY TO MAINTAIN SOME SCT -SHSN WORDING OVER THE NRN PORTION OF THE KEWEENAW OVERNIGHT. AS FOR TEMPS...BASED ON SATELLITE IMAGERY...IT LOOKS LIKE THERE WILL BE A DECENT PERIOD OF CLEAR TO PARTLY CLOUDY SKIES TONIGHT OVER MUCH OF THE AREA. WITH LIGHT WINDS AND PRECIPITABLE WATER 40-55PCT OF NORMAL...FAVORED THE LOW END OF GUIDANCE. TEMPS SHOULD PLUMMET RAPIDLY THIS EVENING WHERE SKIES ARE CLEAR...AND EXPECT TRADITIONAL COLD SPOTS TO FALL TO AROUND -5F. HOWEVER...GIVEN THE SLOW ADVANCE OF UPSTREAM CLOUDS... CLOUDS MAY BE SLOWER TO ARRIVE THAN CURRENTLY FCST. COMBINED WITH FRESH SNOW COVER...COULD EASILY SEE TEMPS FALL TO -10F OR LWR IN THE USUAL COLD SPOTS. SHORTWAVE CURRENTLY MOVING INTO THE DAKOTAS WILL CONTINUE TO DROP SE TOWARD THE TENNESSEE VALLEY TONIGHT/WED AND WILL HAVE NO INFLUENCE HERE AS IT PASSES WELL S OF UPPER MI. OF CONCERN IS THE FOLLOWING SHORTWAVE TROF WHICH WILL SWING SE AND EXTEND FROM JAMES BAY TO MN BY 00Z THU. AS HEIGHT FALLS/MODEST DEEP LAYER FORCING PER QVECTORS OVERSPREAD THE RELATIVELY WARM WATERS OF LAKE SUPERIOR...SFC TROF MOVING OVER THE LAKE WILL SHARPEN UP...RESULTING IN INCREASING CONVERGENCE AND INTENSIFYING LAKE ENHANCED SNOW ALONG/NEAR TROF. EXPECT THIS TROF TO REACH THE KEWEENAW DURING THE MORNING AND THE W IN THE AFTN. TROF PROBABLY WON`T REACH NCNTRL UPPER MI UNTIL EVENING. NE ORIENTATION OF THE WINDS ACROSS THE KEWEENAW AFTER TROF PASSAGE WON`T BE ESPECIALLY FAVORABLE FOR PERSISTENT HEAVIER LAKE ENHANCED SNOW AFTER THE MAIN MDT/HVY SNOW BAND ALONG TROF SHIFTS S. FARTHER S...SHARPER LOW-LEVEL CONVERGENCE AND BETTER UPSLOPING IS EXPECTED INTO ONTONAGON/GOGEBIC COUNTIES...AND THIS IS INDICATED IN MODEL GUIDANCE IN LOW-LEVEL OMEGA FIELDS. WIND FLOW SUGGESTS LAKE NIPIGON PRECONDITONING WILL ALSO COME INTO PLAY OVER THE FAR W. WITH THESE FAVORABLE CONDITIONS CONTINUING INTO THE WED NIGHT...WILL HOIST A LAKE EFFECT SNOW ADVISORY FOR ONTONAGON/GOGEBIC STARTING AT 20Z WED. IN GENERAL...A QUICK COUPLE OF INCHES OF SNOW WILL PROBABLY OCCUR AS THE TROF MOVES ONSHORE OVER THE W. ELSEWHERE...SOME -SN SHOULD GRADUALLY OVERSPREAD THE REST OF WRN UPPER MI IN THE AFTN. TO THE E...IT APEARS WINDS WILL BACK SUFFICIENTLY TO BRING SOME LES OFF LAKE MICHIGAN INTO THE FAR ERN FCST AREA IN THE AFTN. WINDS ARE LIGHT/CONVERGENCE WEAK...SO NOT EXPECTING MUCH WITH THE LES OFF LAKE MI WED (LESS THAN 1 INCH). .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 457 PM EST TUE NOV 25 2014 MAIN FCST CONCERNS IN THE LONG TERM WL FOCUS ON LES POTENTIAL FOR WED NIGHT INTO THANKSGIVING AND NEED FOR HEADLINES AT SENSITIVE TRAVEL TIME. ANOTHER ROUND OF SN WL BE POSSIBLE ON FRI/FRI NIGHT WITH DVLPG ISENTROPIC ASCENT UNDER AN UPPER AIR PATTERN THAT WL SHIFT TO A PROGRESSIVE...ZONAL FLOW BY THE WEEKEND. WELL BLO NORMAL TEMPS WITH SOME RECORD LO MAX TEMPS ON THANKSGIVING WL GIVE WAY TO MUCH WARMER WX ON SAT. ALTHOUGH SOME COLDER AIR WL RETURN FOR SUN INTO MON...A WARMER SW FLOW ON THE WRN FLANK OF HI PRES SHIFTING TO THE E WILL DVLP ON TUE UNDER THIS PROGRESSIVE PATTERN. WED NGT...STEADY N BACKING NNW WIND IN THE WAKE OF PASSING NRN STREAM SHRTWV IS FCST TO ADVECT COLDER AIR INTO THE UPR LKS WITH H85 TEMPS FALLING AS LO AS -18C OVER THE KEWEENAW BY 12Z THU...A FVRBL SETUP FOR LES. EXPECT A PERIOD OF SOME HEAVIER LK ENHANCED SN IN THE FAVORED SN BELTS WHEN AREA OF DPVA/DEEP LYR QVECTOR CNVGC/UVV/DEEP MSTR ASSOCIATED WITH THE PASSING DISTURBANCE COINCIDES WITH FVRBL UPSLOPE...WEAKLY CYC N FLOW. AREAS OVER ONTONAGON/GOGEBIC IN THE EVNG AND MARQUETTE/ALGER COUNTIES IN THE LATER EVNG/EARLY OVERNGT APPEAR TO BE MOST FAVORED TO SEE HEAVIER SN. ENHANCEMENT FACTOR FOR HEAVIER SN TOTALS INCLUDE FAIRLY DEEP DGZ UP TO 4K FT. ALTHOUGH THE SHARPEST UVV IS FCST TO BE JUST BLO THE DGZ MUCH OF THE TIME...THERE WL BE SOME UVV IN THIS ZONE THAT SHOULD ALLOW SN/WATER RATIOS UP TO 20-25:1. ONE NEGATIVE APPEARS TO BE THE ABSENCE OF SHARP CYC FLOW/ PERSISTENT LLVL CNVGC. ALTHOUGH THE LK ENHANCEMENT WL NOT BE A PLAYER WELL INLAND FM LK SUP...DYNAMIC FORCING SHOULD ALLOW FOR SOME LIGHT SN EVEN OVER THE SCENTRAL. BUT ABSENCE OF HIER ABSOLUTE MSTR.. .WITH PWAT NO MORE THAN ABOUT 0.3 INCH AND H7 SPECIFIC HUMIDITY ABOUT 1G/KG...WL LIMIT SN TOTALS TO NO MORE THAN AN INCH OR SO AWAY FM LK ENHANCEMENT/UPSLOPE WINDS. LATER AT NGT...EXPECT THE SN TO DIMINISH NW-SE WITH THE ARRIVAL OF DNVA/DEEP LYR QVECTOR DVGC/ SUBSIDENCE/MID LVL DRYING IN THE WAKE OF THE PASSING SHRTWV THAT IS FCST TO STRENGTHEN INVRN AS LO AS H875-9 AS SHOWN ON NAM FCST SDNGS. ALTHOUGH IT IS NOT COMMON PRACTICE TO ISSUE AN ADVY FOR PRIMARLIY A 3RD PERIOD EVENT...SENSITIVE TRAVEL TIME JUST BEFORE THANKSGIVING HOLIDAY AS WELL AS FAVORABLE UPSLOPE FLOW/FAIRLY EFFICIENT SN GROWTH PARAMETERS WARRANTS EARLY ISSUANCE OF AN LES ADVY IN THE FAVORED AREAS OVER THE W/NCENTRAL DESPITE THE RATHER FLUFFY NATURE OF THE SN THAT IS EXPECTED TO FALL. THE LES ADVY WL INCLUDE GOGEBIC/ ONTONAGON/MARQUETTE AND ALGER COUNTIES. AS MUCH AS 7 TO 8 INCHES OF SN WL FALL IN THESE AREAS THRU THE ADVY PERIOD. N WINDS GUSTING UP TO 25-30 MPH WL CAUSE SOME BLSN NEAR LK SUP WED NIGHT INTO THU MRNG. THANKSGIVING/THU NGT...THE LLVL FLOW IS PROGGED TO BACK STEADILY AND TURN MORE ACYC ON THANKSGIVING WITH SFC HI PRES MOVING TOWARD SW WI LATE IN THE DAY UNDER HGT RISES/DNVA IN ADVANCE OF APRCHG SHRTWV RDG. THE RESULT WL BE SHIFTING/DIMINISHING LES BANDS...ESPECIALLY OVER THE W HALF. THE SN SHOWERS SHOULD END COMPLETELY AT IWD LATE IN THE AFTN. THE LES WL BE MORE PERSISTENT IN THE FAVORED SN BELTS E OF MARQUETTE WITH H85 THERMAL TROF/TEMPS ARND -18C REACHING THAT AREA LATE IN THE DAY...BUT INCRSG ACYC FLOW AND ABSENCE OF SGNFT LLVL CNVGC/LOWERING INVRN BASE TO H875-9 SHOWN ON THE FCST SDNGS UNDER THE NEGATIVE DYNAMICS WL LIMIT SN TOTALS. THANKSGIVING WL BE QUITE CHILLY WITH H85 THERMAL TROF PASSING OVHD AND COULD FEATURE SOME RECORD LO MAX TEMPS. EXPECT THE LOWEST TEMPS OVER THE W HALF WHERE BACKING FLOW WL LIMIT LK SUP MODERATION. AS THE SFC RDG AXIS SHIFTS TO THE E AND THE FLOW BACKS TO THE W-SW...LINGERING LES WL SHIFT OUT INTO LK SUP ON THU NGT. TEMPS COULD FALL QUICKLY IN THE EVNG TOWARD THE LO END OF GUIDANCE BEFORE MORE HI CLDS OVERSPREAD THE AREA W-E ASSOCIATED WITH DVLPG ISENTROPIC ASCENT IN THE SW FLOW ON THE NW FLANK OF PRES SHIFTING INTO THE OH RIVER VALLEY AND IN ADVANCE OF SHRTWV STREAKING EWD TOWARD MN. SOME OF THE FASTER MODELS SHOW SN ASSOCIATED WITH THIS WAA/SHRTWV REACHING THE FAR W BY 12Z FRI...SO WL MAINTAIN SOME LO CHC POPS IN THIS AREA LATE THU NGT. FRI/FRI NGT...AS THE UPR TROF IN ERN NAMERICA SHIFTS TO THE E...THE FLOW OVER THE CONUS/SRN CANADA WL BECOME MORE ZONAL. DVLPG LLVL SW FLOW/ISENTROPIC ASCENT OVER THE GREAT LKS ON THE NW FLANK OF SFC HI PRES SHIFTING INTO THE SRN MID ATLANTIC STATES AND IN ADVANCE OF SHRTWV TRACKING EWD THRU MN IS PROGGED BY MOST OF THE MEDIUM RANGE GUIDANCE TO BRING ABOUT SOME INCRSG MID LVL MSTR/PCPN ON FRI TO THE NE OF AN H85 WARM FNT STRETCHING FM THE NRN PLAINS INTO MN AND WI. ALTHOUGH INITIAL SHOT OF SHARPER ISENTROPIC ASCENT BEST SHOWN ON THE 280-290K SFCS/H85-7 FGEN AXIS/DEEP LYR QVECTOR CNVGC IS FCST TO IMPACT NRN WI ON FRI MRNG...THIS WAA/FORCING MAY SHIFT FARTHER N INTO UPR MI DURING THE DAY. H7 SPECIFIC HUMIDITY IS FCST AS HI AS 3 G/KG...SO NOT OUT OF THE QUESTION THERE COULD BE SOME MODERATE SN AMOUNTS APRCHG ADVY CRITERIA OVER THE SRN CWA. AS THE H925 WINDS BECOME MORE S IN THE PRESENCE OF H85 TEMPS IN THE -8 TO -10C RANGE...LES OFF LK MI WL IMPACT THE ERN CWA. WL MAINTAIN THE HIER POPS/QPF IN THIS AREA. ON FRI NGT...MORE NOTABLE MODEL DIFFERENCES ARE SHOWING UP WITH THE 12Z GFS SHOWING A MORE WNW VS W FLOW ALOFT AND A STRONGER SHRTWV/SFC LO TRACKING FASTER E ACROSS LK SUP ON FRI NGT...WITH CYC NW FLOW OF COLDER AIR DVLPG OVER THE CWA LATE FRI NGT. THIS SOLUTION IS VERY MUCH AN OUTLIER EVEN AMONG THE MOST RECENT GFS ENSEMBLE GUIDANCE... SO TENDED TO FOLLOW THE MORE CONSISTENT 12Z CNDN/00Z AND 12Z ECMWF MODELS. THIS GUIDANCE SHOWS A SLOWER SFC LO AND MORE AGGRESSIVE PUSH TO THE NE OF H85 WARM FNT...WITH H85 TEMPS RISING ABOVE 0C OVER THE SCENTRAL CWA BY 12Z SAT ACCOMPANYING DRY SLOTTING/LOWERING POPS OVER THE SRN TIER. WITH ECWMF SDNGS SHOWING LINGERING LLVL MSTR BLO THE WARMING/DRYING WARM NOSE ARND H85...ADDED A MENTION OF SOME FREEZING DZ OVER THE SW CWA. SAT/SAT NGT...SHRTWV EMBEDDED IN ZONAL FLOW OVER SRN CANADA WL STREAM E...WITH ACCOMPANYING SFC LO STREAKING ENEWD THRU ONTARIO AND THEN DRAGGING A COLD FNT ACRS THE CWA SAT NGT. AHEAD OF THIS FNT... MORE CONSISTENT...FAVORED 12Z ECMWF/CNDN MODELS SHOW WARM SURGE INTO THE UPR LKS WITH H85 TEMPS RISING AS HI AS 8-10C OVER THE SRN TIER ON SAT UNDER SOME MID LVL DRYING. TENDED TO CUT POPS OVER THE SRN TIER...WHERE THE ECMWF AND CNDN MODELS SHOW MORE AGGRESSIVE MID LVL DRYING FARTHER FM THE LO TRACK. CONTINUED TO MENTION SOME RA OR FREEZING DZ IN THESE AREAS AS WELL. FARTHER TO THE N CLOSER TO THE LO TRACK AND SOMEWHAT HIER CHC POPS...INCLUDED MENTION OF FREEZING RA AND RA IN ADDITION TO SN IN CASE THE AIRMASS IS A BIT COLDER. IF SFC TEMPS END UP HIER THAN CURRENTLY FCST...LATER SHIFTS MAY BE ABLE TO CUT BACK ON THE FREEZING DZ/RA AND GO WITH PLAIN RA. RIGHT NOW... LOOKS LIKE ANY ICE ACCUMULATION WL BE MINOR. EXTENDED...MUCH COLDER AIR...WITH H85 TEMPS FCST AS LO AS -18C BY 00Z MON...AND SOME LK EFFECT SN WL FOLLOW ON SUN UNDER NW FLOW BTWN DEPARTING COLD FNT AND CNDN HI PRES BLDG E THRU THE NRN PLAINS. BUT SINCE THE UPR FLOW WL REMAIN FAIRLY PROGRESSIVE...THE SFC HI PRES WL SHIFT THRU THE GREAT LKS ON MON AND INTO NEW ENGLAND TUE AS UPR RDG BLDS INTO THE UPR LKS ON TUE. THE RESULT SHOULD BE DIMINISHING LES ON MON WITH DRY WX LINGERING INTO TUE. WARMER SW FLOW ON THE WRN FLANK OF DEPARTING SFC HI PRES MAY DRAW ENUF MSTR TO THE N ON TUE TO BRING A RETURN OF SOME SN OR A RA/SN MIX. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1256 AM EST WED NOV 26 2014 VFR CONDITIONS WILL CONTINUE AT KIWD/KSAW TONIGHT AND WILL CONTINUE AT KSAW THROUGH WED. NEXT APPROACHING DISTURBANCE WILL BRING SOME -SN/MVFR CONDITIONS TO KIWD BY WED AFTERNOON WHICH WILL FALL TO IFR LATE WED AFTERNOON LASTING INTO THE EVENING. AT KCMX...WINDS MAY RETAIN ENOUGH OVERWATER COMPONENT TO MAINTAIN MVFR CONDITIONS THRU MOST OF THE PERIOD. KSAW WILL FALL TO IFR CONDITIONS BY WED EVENING AS SNOW MOVES IN. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 450 PM EST TUE NOV 25 2014 PRES GRADIENT RAPIDLY WEAKENS TONIGHT WITH A WEAK SFC TROF DROPPING SE OVER LAKE SUPERIOR. THIS WILL RESULT IN WINDS DIMINISHING TO UNDER 20KT ACROSS THE LAKE. STRONG HIGH PRES WILL THEN BUILD SE INTO THE CANADIAN PRAIRIES WED AND INTO THE NRN PLAINS WED NIGHT. THIS WILL PUSH THE TROF SE AND TIGHTEN THE PRES GRADIENT. AS A RESULT... WITH THE TROF PASSAGE...EXPECT NORTHERLY WINDS TO RAMP UP TO 20-30KT FROM NW TO SE WED/WED NIGHT. NOT OUT OF THE QUESTION THAT THERE COULD BE SOME GALE FORCE GUSTS OVER THE CNTRL PORTION OF LAKE SUPERIOR. WINDS WILL THEN DIMINISH TO UNDER 20KT W TO E THU/THU NIGHT AS HIGH PRES RIDGE ARRIVES. WITH ANOTHER COLD FRONT PUSHING ACROSS THE UPPER LAKES SAT...EXPECT INCREASING WINDS TO 15-25KT FRI/FRI NIGHT AHEAD OF FRONT. BEHIND FRONT...NW WINDS MAY REACH 20-30KT LATE SAT/SUN. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 10 PM THIS EVENING TO 1 PM EST THURSDAY FOR MIZ006. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 10 AM EST THURSDAY FOR MIZ005. LAKE EFFECT SNOW ADVISORY FROM 3 PM EST /2 PM CST/ THIS AFTERNOON TO 10 AM EST /9 AM CST/ THURSDAY FOR MIZ002-009. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...KC AVIATION...JLA MARINE...ROLFSON
AREA FORECAST DISCUSSION...UPDATED
NWS TWIN CITIES/CHANHASSEN MN
1148 PM CST TUE NOV 25 2014 .UPDATE... ISSUED AT 926 PM CST TUE NOV 25 2014 EXPANDED THE WINTER WEATHER ADVISORY NORTH A COUPLE ROWS OF COUNTIES TO INCLUDE AREAS FROM WILLMAR TO ST PAUL AND SOUTH. THE NAM AND GFS CONTINUE TO ADVERTISE THE NORTHERN BATCH OF SNOW OVER NORTH DAKOTA WEAKENING OVERNIGHT AS IT HEADS SOUTHEAST...WITH THE SOUTH DAKOTA BATCH PUSHING INTO SOUTHWEST MINNESOTA OVERNIGHT. AN INVERTED TROUGH IS EXPECTED TO DEVELOP WEDNESDAY...WITH THE NORTHERN BATCH ENERGIZING AFTER SUNRISE ACROSS MOST OF EAST CENTRAL MINNESOTA. THE 21Z SREF HAS SHIFTED NORTH TO COME INTO LINE WITH THE NAM AND GFS...AND THE HI-RES MODELS OF HOPWRF...HRRR...AND TO SOME DEGREE THE RAP IN BRINGING THE BULLS EYE OF HEAVIEST SNOW FROM JUST NORTH OF MANKATO INTO THE FAR SOUTHWESTERN TWIN CITIES SUBURBS. THIS IS THE AREA WHERE THIS ENERGIZED BATCH OF SNOW IS EXPECTED TO LINGER FOR SOME TIME DURING THE LATE MORNING AND EARLY AFTERNOON LEADING TO AT LEAST A FEW TO AS MUCH AS 5 INCHES. SNOW WILL QUICKLY DISSIPATE DURING MID AFTERNOON...WITH A SHARP CUT OFF TO SNOW AMOUNTS TO THE EAST OVER FAR WESTERN WI. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY) ISSUED AT 415 PM CST TUE NOV 25 2014 THE MAIN CONCERN IN THE SHORT TERM IS A CLIPPER SYSTEM MOVING SOUTHEAST FROM THE DAKOTAS TO IOWA TONIGHT AND WEDNESDAY. THERE REMAINS QUITE A BIT OF SPREAD IN THE QPF FROM THE VARIOUS DETERMINISTIC SOLUTIONS TODAY ON HOW FAR EAST SIGNIFICANT ACCUMULATING SNOW (3+") WILL GO ON WEDNESDAY. ALTHOUGH THE H7 LOW ASSOCIATED WITH THE CLIPPER WILL BASICALLY PASS ACROSS SOUTHWEST MN LATE TONIGHT...A SECOND SHORT WAVE IS PUSHING ACROSS FAR NORTHERN MN DURING THIS SAME TIME. THE NAM AND THE GFS HAVE MUCH MORE QPF SPREADING NORTHEAST AHEAD OF THE NORTHERN STREAM FEATURE...WHICH IF TRUE...WOULD RESULT IN MUCH MORE SNOW ACROSS EASTERN MN AND WEST CENTRAL WI THEN CURRENTLY FORECAST...WHICH IS IN THE 1 TO 2 INCH RANGE. THE GEM AND ECMWF HAVE MORE SEPARATION IN THE QPF...WITH MUCH OF THE SNOW FOCUSED FROM WEST CENTRAL THROUGH SOUTH CENTRAL MINNESOTA LATE TONIGHT AND WEDNESDAY. ITS INTERESTING TO NOTE THAT THE PAST FIVE RUNS OF THE ECMWF HAVE SHOWN THE MID LEVEL LOW SINKING SLOWLY SOUTHWARD WITH TIME WHICH WOULD KEEP THE HEAVIEST SNOW TO THE WEST AND SOUTH OF THE TWIN CITIES. THE 15Z SREF IS BASICALLY IN LINE WITH THIS IDEA...SHOWING THE HIGHEST PROBABILITIES (60-80 PERCENT) FOR GREATER THAN 0.25 INCHES OF QPF IN 12 HOURS FROM WEST CENTRAL THROUGH SOUTH CENTRAL MINNESOTA. THERE IS A LITTLE BIT OF A FINGER OF HIGHER PROBABILITIES POINTING TOWARDS THE SOUTHWEST TWIN CITIES METRO. HENCE...WITH CONFIDENCE HIGHEST FOR 3+ INCHES OF SNOW LATE TONIGHT AND WEDNESDAY MORNING FROM WEST CENTRAL THROUGH SOUTH CENTRAL MINNESOTA...A WINTER WEATHER ADVISORY WAS ISSUED FOR THESE AREAS. WITH SOME HINT THAT THE HEAVIER SNOW COULD GET A LITTLE MORE TO THE EAST...THE ADVISORY REACHES ACROSS MCLEOD AND SIBLEY COUNTIES. KEPT THE ADVISORY GOING ALONG THE I-35 CORRIDOR FROM NORTHFIELD TO ALBERT LEA DURING THE AFTERNOON WHERE SNOW WILL LINGER. LOW TEMPERATURES TONIGHT ARE A LITTLE TRICKY WITH THE LOW CLOUDS TRYING TO DIMINISH SOME THIS EVENING WHILE SOUTHERLY LOW LEVEL FLOW/WAA INCREASES. WENT ON THE LOW SIDE OF GUIDANCE WITH DEW POINTS ONLY IN THE SINGLE DIGITS AND TEENS ALONG WITH SOME SNOW COVER. HIGHS ON WEDNESDAY ONLY IN THE TEENS ACROSS THE WEST WITH LOWER TO MIDDLE 20S EAST. .LONG TERM...(WEDNESDAY NIGHT THROUGH TUESDAY) ISSUED AT 415 PM CST TUE NOV 25 2014 THE LONG TERM CONTINUES THE PUSH PULL WEATHER PATTERN WITH BRIEF WARM UP/COOL DOWNS. THE INITIAL WAVE EXITS EARLY WEDNESDAY NIGHT...WITH COOLER HIGH PRESSURE FOLLOWING FOR THANKSGIVING DAY. HIGH TEMPERATURES EXPECTED TO REMAIN IN THE TEENS ONCE AGAIN. THE NEXT WAVE MOVES IN WITH WAA DRIVING EAST ACROSS THE AREA THANKSGIVING NIGHT AND FRIDAY. A GENERAL 2-3 INCH SNOW IS LIKELY ALONG AND NORTHEAST OF I-94. THE WARM FRONT LIFTS NORTH ACROSS THE CWA. DEPENDING ON SUNSHINE...TEMPERATURES COULD WARM THROUGH THE 30S AGAIN...ESPECIALLY IN THE FAR SOUTH. HOWEVER...THERE IS SOME MODEL TIMING ISSUES...WITH THE GFS FASTER WITH THE NEXT COLD FRONT. WILL MOVE TOWARDS A SLOWER AND WARMER SOLUTION FOR NOW...WITH SOME SMALL CHANCE POPS ASSOCIATED WITH THIS FRONT. BETTER FORCING AND BAROCLINIC ZONE DEVELOPS ALONG THE NORTHERN PERIPHERY OF THE AREA. THE PRECIPITATION...IF IT DOES DEVELOP..COULD BE IN THE FORM OF FREEZING DRIZZLE/LIGHT SNOW OR FLURRIES. THE GFS IS THE MORE ROBUST MODEL IN THE OVERALL DEVELOPMENT ACROSS THE REGION. ARCTIC HIGH PRESSURE DROPS SOUTH AGAIN OVER THE CWA FOR SATURDAY AND SATURDAY NIGHT. WE SHOULD SEE CLOUDS CLEAR OUT OF THE AREA DURING THE DAY SUNDAY...PROVIDING DRIVE HOLIDAY TRAVEL FOR THE AREA. COLD TEMPERATURES RETURN WITH HIGHS IN THE TEENS BOTH SUNDAY AND MONDAY...BEFORE THE NEXT UPPER TROUGH SWINGS OVER THE WESTERN CONUS AND DRIVES WARMER AIR BACK NORTH AND EAST TOWARD THE NORTHERN PLAINS/WESTERN GREAT LAKES FOR TUESDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1139 PM CST TUE NOV 25 2014 CONFIDENCE HAS INCREASED FROM THE LAST SET OF TAFS REGARDING THE SNOW FOR WEDNESDAY. IT HAS ALREADY BEGUN PUSHING INTO THE RWF AREA AND WILL TAKE ANOTHER HOUR OR TWO TO REACH AXN. EASTWARD PROGRESSION WILL SLOW OVERNIGHT...THEN BEGIN TO DEVELOP FURTHER EAST INTO THE TWIN CITIES METRO AND STC SHORTLY BEFORE DAWN. INVERTED TROUGH SHOULD CONCENTRATE MUCH OF THE SNOW DURING THE DAYTIME IN AN AREA FROM STC TO RWF...MKT...AND MSP. SNOW RATES WILL INCREASE BETWEEN 12-18Z IN THIS AREA WHERE 1/2 TO 1 INCH PER HOUR RATES ARE POSSIBLE FOR A TIME. THE SNOW WILL TAPER OFF DURING THE AFTERNOON FROM WEST TO EAST. ONLY LOOKING FOR A 2 TO 4 HOUR WINDOW OF LIGHT SNOW ACROSS WRN WI...MAINLY DURING THE MID AFTERNOON TO EARLY EVENING. KMSP...LIGHT SNOW LOOKS LIKE IT WILL BEGIN AROUND 12Z...AND COULD BECOME MORE INTENSE BETWEEN 14-19Z WHEN SNOWFALL RATES OF 1/2 TO 1 INCH PER HOUR AND IFR/LIFR CONDITIONS ARE POSSIBLE. THE SNOW WILL TAPER OFF MID AFTERNOON WITH VFR CONDITIONS EXPECTED AFTER MID EVENING. /OUTLOOK FOR KMSP/ THU...VFR. NW 4-8 KTS. FRI...CHC MVFR AND -SN. WINDS SE 5 KTS. SAT...CHC MVFR. WINDS NORTH 10 KTS. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY FROM 6 AM TO 6 PM CST WEDNESDAY FOR MNZ059-060-062-068>070-076-077-084-085-093. WINTER WEATHER ADVISORY UNTIL NOON CST WEDNESDAY FOR MNZ054- 056>058-064>067-073>075-082-083-091-092. WI...NONE. && $$ UPDATE...BORGHOFF SHORT TERM...RAH LONG TERM...DWE AVIATION...BORGHOFF
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
318 PM CST WED NOV 26 2014 .SYNOPSIS... ISSUED AT 318 PM CST WED NOV 26 2014 H5 ANALYSIS FROM THIS MORNING HAS A CLOSED LOW OVER NUNAVUT WITH A TROUGH EXTENDING SWD INTO THE SERN CONUS. A COUPLE OF UPPER LEVEL DISTURBANCES WERE NOTED OVER KENTUCKY AND NRN MO. STRONG WINDS WERE NOTED IN THE MID LEVELS AS A 90+KT H5 JET STREAK EXTENDED FROM WESTERN MT INTO SWRN KS. AT THE SURFACE...LOW PRESSURE WAS PRESENT OVER NRN MO WITH A COLD FRONT EXTENDING SOUTH AND WEST OF THE LOW INTO THE OZARKS AND TX PANHANDLE. COLD AIR BEHIND THE FRONT HAS BACKED TO ALONG THE FRONT RANGES OF THE ROCKIES IN COLORADO AND WYOMING. LOOKING AT THE H7 THERMAL FIELD...A DECENT FRONTAL BOUNDARY EXTENDED ACROSS THE PANHANDLE AND EXTREME SOUTHWESTERN NEBRASKA. THE H7 FRONT...COUPLED WITH THE H5 JET STREAK...HAS LED TO LIGHT SNOW ACROSS THE PANHANDLE AND NORTHEASTERN COLORADO THIS AFTERNOON. SKIES WERE MOSTLY CLOUDY ACROSS WESTERN AND NORTH CENTRAL NEBRASKA THIS AFTERNOON. TEMPERATURES AS OF MID AFTERNOON RANGED FROM 25 AT ONEILL TO 34 AT NORTH PLATTE AND OGALLALA. && .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 318 PM CST WED NOV 26 2014 LOW TO MID LEVEL FRONTOGENETIC BAND CURRENTLY ACROSS SOUTHWEST NEBRASKA IS SHOWN BY THE HIRES NEAR TERM MODELS TO BECOME LESS DEFINED THROUGH THE AFTERNOON AS THE ATMOSPHERE LOSES SATURATION IN THE DENDRITIC GROWTH ZONE. THE HRRR SEEMS TO BE HANDLING THE CURRENT SITUATION WELL...THUS THE FORECAST WAS TRENDED IN THAT DIRECTION WITH SNOW ENDING ACROSS OUR SOUTHWEST THIS EVENING. THE LATEST HRRR DOES SHOW ANOTHER PUSH OF LOWER LEVEL MOISTURE THIS EVENING...THUS THE REASON OF EXTENDING A SNOW MENTION INTO THIS EVENING. ACROSS NORTH CENTRAL NEBRASKA THIS EVENING...BUFR SOUNDINGS SHOW DEEP SATURATION...WHICH AT TIMES REACHES INTO THE DGZ...WHATS MISSING IS DEEP LIFT...BUT THERE ARE INDICATIONS OF AT LEAST WEAK OMEGA. PREVIOUS FORECAST HANDLED THIS POTENTIAL WITH --SN...WILL DO THE SAME. OVERNIGHT LOWS WILL BE CHILLY...WITH LESS MIXING IN MIND OVERNIGHT LOWS SHOULD BOTTOM OUT IN THE TEENS ACROSS THE EAST...WITH LOWER 20S OVER THE HIGHER TERRAIN OF THE WEST. TOMORROW...A GENERAL WARMING AND DRYING TREND IS FORECAST BY ALL AVAILABLE GUIDANCE AS SFC HIGH PRESSURE BUILDS OFF TO THE EAST AND A LEE TROUGH DEEPENS TO THE WEST. SOUTHERLY...TO WESTERLY FLOW WILL ADVECT WARMER H85 TEMPS ACROSS THE REGION...WITH OUR FAR WESTERN & SOUTHWESTERN ZONES TOPPING 10C BY 00Z FRIDAY. THIS SHOULD PROVIDE FOR TEMPERATURES IN THE LOWER 60S ACROSS SOUTHWEST NEBRASKA AND THE EASTERN PANHANDLE. THERE WILL REMAIN A SHARP GRADIENT OF TEMPERATURES AS ONE HEADS EAST. ACROSS THE HEART OF THE SANDHILLS HIGHS IN THE 40S AND 50S SHOULD PREVAIL...TO THE EAST OF THERE...ACROSS NORTH CENTRAL NEBRASKA...HIGHS MAY STRUGGLE TO REACH INTO THE MID 30S...OWING THE PRESENCE OF PERSISTENT STRATUS AND COOLER AIR RECYCLED FROM THE DEPARTING HIGH. YOUR THANKSGIVING FORECAST IS DRY AS THE TROPOSPHERIC COLUMN IS SHOWN TO DRY ON THURSDAY. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 318 PM CST WED NOV 26 2014 MID RANGE...THURSDAY NIGHT THROUGH SATURDAY...IN THE MID RANGE...UNSEASONABLY WARM AND DRY CONDITIONS ARE EXPECTED...WITH THE MAIN FORECAST CHALLENGE BEING HIGH TEMPERATURES FOR FRIDAY AND SATURDAY. FOR THURSDAY NIGHT...A WARM FRONT WILL CONTINUE TO LIFT NORTHEAST OF THE AREA INTO NORTH DAKOTA AND MINNESOTA. A WEAK SURFACE TROUGH OF LOW PRESSURE WILL DEVELOP ACROSS THE HIGH PLAINS OF NEBRASKA AND KANSAS OVERNIGHT LEADING TO LIGHT WESTERLY WINDS. OVERNIGHT LOWS WILL BE ON THE MILD SIDE FOR THIS TIME OF YEAR WITH READINGS AROUND 25 FORECAST FOR FRIDAY MORNING. WITH LIGHT WESTERLY WINDS FORECAST...WENT WITH SOME LOWER 20S IN THE PLATTE RIVER VALLEY. FRIDAY AND FRIDAY NIGHT...WARM H85 TEMPS WILL PUSH INTO THE REGION WITH H85 TEMPS RANGING FROM 8 TO 16C. THIS WILL RESULT IN HIGHS WELL INTO THE 50S TO MIDDLE 60S FRIDAY AFTERNOON. ON FRIDAY NIGHT...LOWS WILL BE MILD WITH TEMPERATURES IN THE UPPER 20S TO LOWER 30S EXPECTED. ON SATURDAY...AN ARCTIC COLD FRONT WILL PUSH INTO THE DAKOTAS...ENDING UP SOMEWHERE IN SOUTH DAKOTA BY 00Z SUNDAY. THE EURO SOLN IS MOST AGGRESSIVE WITH THE FRONT BEING ALONG THE SD/NE BORDER BY THIS TIME. THE NAM AND GFS ARE SLOWER AND HAVE THE FRONT OVER CENTRAL AND NORTHERN SD DURING 00Z SUNDAY. REGARDLESS...THE FRONT WILL BE NORTH OF THE FORECAST AREA BEFORE PEAK HEATING. WITH THE APPG FRONT AND H85 TEMPS REACHING THE MIDDLE TO UPPER TEENS SAT AFTN...HIGHS WILL SURGE INTO THE 60S AND MAY APPROACH 70 IN THE SOUTHWEST. RECORDS FOR SATURDAY ARE IN THE MID 70S FOR VALENTINE AND IMPERIAL...AND 71 FOR NORTH PLATTE AND 69 FOR BROKEN BOW RESPECTIVELY. LONG RANGE...SATURDAY NIGHT THROUGH WEDNESDAY...A STRONG ARCTIC FROPA WILL PUSH THROUGH THE FORECAST AREA SATURDAY NIGHT. FORECAST WILL CONTINUE TO BE DRY BEHIND THE FRONT WITH THE BEST FORCING OVER NORTH DAKOTA AND NRN MINNESOTA. H85 TEMPS BEHIND THE FRONT SUNDAY WILL RANGE FROM -13C IN THE NORTH TO -7C IN THE SOUTH. WITH DECENT NORTHERLY WINDS AND MIXING HIGHS WILL STRUGGLE TO GET OUT OF THE 20S SUNDAY. TEMPERATURES WILL MODERATE SOME MONDAY...WITH A BETTER WARMUP EXPECTED ON TUESDAY AND WEDNESDAY. BY WEDNESDAY...THE PRECIPITATION FORECAST BECOMES MORE OF A CHALLENGE THANKS TO SPLIT FLOW. THE LATEST GFS AND ECMWF HAVE DIVERGENT SOLUTIONS TOWARD THE MIDDLE OF THE WEEK. THE GFS IS MOST AGGRESSIVE...PUSHING A SHORTWAVE TROUGH ACROSS THE INTERMOUNTAIN WEST WEDNESDAY...WHILE THE ECMWF HAS THE TROUGH IN NRN CALIFORNIA. WITH THE MODEL DISAGREEMENTS ATTM...WILL LEAVE THE PERIOD DRY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1105 AM CST WED NOV 26 2014 .AVIATION...MODEL GUIDANCE CONTINUES TO INDICATE MVFR OR LOWER CEILINGS THAT WILL EVENTUALLY BREAK THIS AFTERNOON AT KLBF. SKIES ARE ANTICIPATED TO BE VFR BY 20Z. AT KVTN...SKIES WILL REMAIN OVERCAST THROUGH MUCH OF THE DAY...IN FACT MUCH OF THE NEAR TERM GUIDANCE INDICATES KVTN REMAINING AT MVFR OR LOWER THROUGH THE FORECAST CYCLE. WILL BRIEFLY INCLUDE A SCT030 CEILING THIS AFTERNOON AT KVTN...BUT THEN TREND SKIES BELOW MVFR THIS EVENING. OTHERWISE -SN IS CURRENTLY FALLING ACROSS THE EASTERN PANHANDLE...IMPACTS FROM THE SNOW THIS AFTERNOON WILL BE MINIMAL AS VISBY REDUCTIONS WILL ONLY FALL BRIEFLY BLO 6SM...THIS SNOW IS NOT ANTICIPATED TO IMPACT KLBF OR KVTN. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...CLB SHORT TERM...JACOBS LONG TERM...CLB AVIATION...KECK/JACOBS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
559 PM EST WED NOV 26 2014 .SYNOPSIS... SNOW WILL CONTINUE INTO THIS EVENING...BEFORE WINDING DOWN LATE TONIGHT...AS A STRENGTHENING STORM SYSTEM TRACKS FARTHER OFF THE EAST COAST. A SERIES OF UPPER-LEVEL DISTURBANCES WILL BRING OCCASIONAL LIGHT SNOW SHOWERS AND FLURRIES FRIDAY AND SATURDAY...WITH TEMPERATURES STAYING ON THE CHILLY SIDE. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 4 PM UPDATE... BASED ON PERSISTENCE OF NARROW CSI BAND...AND THE EXPECTATION OF ANOTHER 2-3 HRS OF +SN UNDERNEATH IT...WE`VE ADDED BRADFORD PA AND TIOGA NY TO THE WRNG AREA (STORM TOTALS OF 5-10"). 3 PM UPDATE... FOR THE MOST PART...ONGOING WINTER STORM IS BEHAVING ITSELF...AS A DEEPENING SURFACE CYCLONE IS MOVING NEWD OFF THE MID-ATLANTIC COAST. OF PRIMARY CONCERN LATE THIS AFTN INTO THE EVE HRS IS THE TRACK OF THE MID-LVL LOW (700 MB)...AND AN ASSOCD BAND OF FGEN FORCING...FROM CNTRL/NERN PA INTO PTNS OF NY`S SRN TIER...THEN NEWD FROM THERE. BASED ON THE LATEST OBSERVATIONAL DATA...SPC MESO-ANALYSES...AND THE LATEST HI-RES MODEL OUTPUT...THE MAIN BAND OF +SN MAY WELL IMPACT AN AXIS FROM NEAR WILLIAMSPORT...TO TOWANDA...TO BINGHAMTON...TO NORWICH AND COOPERSTOWN THROUGH AT LEAST 21-23Z...WITH A GENERAL EWD SHIFT THEREAFTER. ACRS OUR SERN ZNS...PROXIMITY OF A MID-LVL DRY SLOT MAY CAUSE SNOW TO OCNLLY DECREASE...BUT IT`S NOT LIKELY TO SHUT DOWN ALTOGETHER UNTIL LTR THIS EVE...SO ADDITIONAL ACCUMS ARE STILL ANTICIPATED EVEN IN THESE AREAS. ALL IN ALL...CURRENTLY ADVERTISED SNOWFALL TOTALS STILL LOOK REASONABLE...WITH A GENERAL 6-12" IN THE WRNG AREA OVER MOST OF NERN PA...THE CATSKILLS...AND SXNS OF THE SUSQ RGN...AND ROUGHLY 3-6" IN THE ADVISORY RGN...FROM KELM-KITH-KSYR. BASED ON THE LATEST HRRR DATA...WHICH HAS PERFORMED WELL TDY...THE BACK EDGE OF THE STEADIER SNOW PULLS OUT FROM W TO E AFTER 01-03Z. ALTHOUGH WE COULD SEE SOME WEAK MULTI-BANDS TWDS DAYBREAK IN A 310-330 FLOW...THE OVERALL FLOW LOOKS WEAK...AND MOISTURE DEPTHS WILL BE ON THE DECLINE...SO ACCUMS SHOULD BE VERY MINOR. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... FOR THANKSGIVING DAY AND THU NGT...A NW FLOW PATN WILL PREVAIL...WITH LOW-LVL CAA...AND LINGERING BLYR MOISTURE. FOR THE MOST PART...THIS WILL PRODUCE -SHSN AND FLRYS...AND SMALL ACCUMS. HOWEVER...A BRIEF PD OF ENHANCEMENT COULD OCCUR LTR THU NGT INTO FRI MRNG...WHEN A WELL DEFINED NRN STREAM S/WV CROSSES NY/PA. SOME SYNOPTIC SUPPORT FROM THE S/WV AND LK ENHANCEMENT COULD PRODUCE LOCALLY 1-3" IN AN AXIS FROM SRN CAYUGA-ONONDAGA...TO SRN ONEIDA/MADISON/NRN CHENANGO/NRN OTSEGO. FOR THE REST OF THE DAY FRI INTO FRI NGT...MAINLY JUST SCTD -SHSN/FLRYS ARE AGN ANTICIPATED...WITH BACKING LOW-LVL FLOW...AS SOME WARM ADVECTION BEGINS. ANOTHER S/WV PASSAGE...ALG WITH THE APPROACH OF THE SFC-850 MB WARM FRNT FROM THE SW...COULD LEAD TO ADDTNL -SHSN AND SOME LGT ACCUMS AS WE HEAD INTO EARLY SAT...SPCLY FOR OUR NRN ZNS. DAILY HIGHS WILL GENERALLY BE IN THE 30S...WITH LOWS IN THE UPR TEENS AND 20S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... 230 PM EST UPDATE... FOLLOWED CLOSELY WITH WPC GUIDANCE AND MADE MINOR CHANGES TO THE PREVIOUS FORECAST. THE MAIN THEME OF THE FORECAST CONTINUES WITH ZONAL FLOW STILL BEING EXPECTED ACROSS MUCH OF THE NORTHEAST THROUGH THE FORECAST PERIOD. BY SAT NIGHT A WARM FRONT WILL HAVE JUST PASSED TO THE NORTH OF THE CWA AND A COLD FRONT WILL BE STARTING TO APPROACH THE REGION FROM THE WEST. THIS COLD FRONT WILL BRING COOLER AIR TO THE REGION ALONG WITH A CHANCE FOR RAIN/AND OR SNOW SHOWERS TO NEW YORK AND PENNSYLVANIA. A SFC RIDGE WILL THEN START TO BUILD OVER THE AREA FROM THE WEST MONDAY AFTERNOON... THUS BRINGING DRY AND QUIET WEATHER BACK TO THE AREA THROUGH MID WEEK. THIS RIDGE WILL ALSO ALLOW TEMPERATURES OVER THE REGION TO FALL BELOW THE SEASONAL NORM. THE COLDEST DAY IN THE EXTENDED FORECAST WILL BE WHEN THE RIDGE IS EXPECTED TO BE CENTERED OVER THE CWA. THIS WILL OCCUR ON TUESDAY. HIGH TEMPERATURES ARE EXPECTED TO RISE INTO THE LOW TO MID 30S. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... AN INTENSE BAND OF SNOW EXTENDING FROM NORTHEASTERN NY TOWARD THE AVP TERMINAL WILL CAUSE IFR CONDITIONS FOR A FEW MORE HOURS. THE SNOW WILL TAPER OFF BETWEEN 2Z AND 5Z, WITH MOST TERMINALS POPPING BACK UP TO BETWEEN 2SM AND 5SM VISIBILITY ONCE THE BAND MOVES OUT OR WEAKENS. A GENERAL LIGHT SNOWFALL WILL PERSIST INTO EARLY THURSDAY WITH LIGHT WINDS AND MAINLY MFVR RESTRICTIONS. OUTLOOK... THU NGT/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY KSYR-KRME. SUN...RESTRICTIONS POSSIBLE FROM -SHRA. MON...RESTRICTIONS POSSIBLE FROM -SHRA/SHSN. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR PAZ038>040- 043-044-047-048-072. NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ045-046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NYZ009-017- 018-024-025-036-037-044. && $$ SYNOPSIS...MLJ NEAR TERM...MLJ SHORT TERM...MLJ LONG TERM...KAH AVIATION...DJP/PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
353 PM EST WED NOV 26 2014 .SYNOPSIS... SNOW WILL CONTINUE INTO THIS EVENING...BEFORE WINDING DOWN LATE TONIGHT...AS A STRENGTHENING STORM SYSTEM TRACKS FARTHER OFF THE EAST COAST. A SERIES OF UPPER-LEVEL DISTURBANCES WILL BRING OCCASIONAL LIGHT SNOW SHOWERS AND FLURRIES FRIDAY AND SATURDAY...WITH TEMPERATURES STAYING ON THE CHILLY SIDE. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 4 PM UPDATE... BASED ON PERSISTENCE OF NARROW CSI BAND...AND THE EXPECTATION OF ANOTHER 2-3 HRS OF +SN UNDERNEATH IT...WE`VE ADDED BRADFORD PA AND TIOGA NY TO THE WRNG AREA (STORM TOTALS OF 5-10"). 3 PM UPDATE... FOR THE MOST PART...ONGOING WINTER STORM IS BEHAVING ITSELF...AS A DEEPENING SURFACE CYCLONE IS MOVING NEWD OFF THE MID-ATLANTIC COAST. OF PRIMARY CONCERN LATE THIS AFTN INTO THE EVE HRS IS THE TRACK OF THE MID-LVL LOW (700 MB)...AND AN ASSOCD BAND OF FGEN FORCING...FROM CNTRL/NERN PA INTO PTNS OF NY`S SRN TIER...THEN NEWD FROM THERE. BASED ON THE LATEST OBSERVATIONAL DATA...SPC MESO-ANALYSES...AND THE LATEST HI-RES MODEL OUTPUT...THE MAIN BAND OF +SN MAY WELL IMPACT AN AXIS FROM NEAR WILLIAMSPORT...TO TOWANDA...TO BINGHAMTON...TO NORWICH AND COOPERSTOWN THROUGH AT LEAST 21-23Z...WITH A GENERAL EWD SHIFT THEREAFTER. ACRS OUR SERN ZNS...PROXIMITY OF A MID-LVL DRY SLOT MAY CAUSE SNOW TO OCNLLY DECREASE...BUT IT`S NOT LIKELY TO SHUT DOWN ALTOGETHER UNTIL LTR THIS EVE...SO ADDITIONAL ACCUMS ARE STILL ANTICIPATED EVEN IN THESE AREAS. ALL IN ALL...CURRENTLY ADVERTISED SNOWFALL TOTALS STILL LOOK REASONABLE...WITH A GENERAL 6-12" IN THE WRNG AREA OVER MOST OF NERN PA...THE CATSKILLS...AND SXNS OF THE SUSQ RGN...AND ROUGHLY 3-6" IN THE ADVISORY RGN...FROM KELM-KITH-KSYR. BASED ON THE LATEST HRRR DATA...WHICH HAS PERFORMED WELL TDY...THE BACK EDGE OF THE STEADIER SNOW PULLS OUT FROM W TO E AFTER 01-03Z. ALTHOUGH WE COULD SEE SOME WEAK MULTI-BANDS TWDS DAYBREAK IN A 310-330 FLOW...THE OVERALL FLOW LOOKS WEAK...AND MOISTURE DEPTHS WILL BE ON THE DECLINE...SO ACCUMS SHOULD BE VERY MINOR. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY/... FOR THANKSGIVING DAY AND THU NGT...A NW FLOW PATN WILL PREVAIL...WITH LOW-LVL CAA...AND LINGERING BLYR MOISTURE. FOR THE MOST PART...THIS WILL PRODUCE -SHSN AND FLRYS...AND SMALL ACCUMS. HOWEVER...A BRIEF PD OF ENHANCEMENT COULD OCCUR LTR THU NGT INTO FRI MRNG...WHEN A WELL DEFINED NRN STREAM S/WV CROSSES NY/PA. SOME SYNOPTIC SUPPORT FROM THE S/WV AND LK ENHANCEMENT COULD PRODUCE LOCALLY 1-3" IN AN AXIS FROM SRN CAYUGA-ONONDAGA...TO SRN ONEIDA/MADISON/NRN CHENANGO/NRN OTSEGO. FOR THE REST OF THE DAY FRI INTO FRI NGT...MAINLY JUST SCTD -SHSN/FLRYS ARE AGN ANTICIPATED...WITH BACKING LOW-LVL FLOW...AS SOME WARM ADVECTION BEGINS. ANOTHER S/WV PASSAGE...ALG WITH THE APPROACH OF THE SFC-850 MB WARM FRNT FROM THE SW...COULD LEAD TO ADDTNL -SHSN AND SOME LGT ACCUMS AS WE HEAD INTO EARLY SAT...SPCLY FOR OUR NRN ZNS. DAILY HIGHS WILL GENERALLY BE IN THE 30S...WITH LOWS IN THE UPR TEENS AND 20S. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... 230 PM EST UPDATE... FOLLOWED CLOSELY WITH WPC GUIDANCE AND MADE MINOR CHANGES TO THE PREVIOUS FORECAST. THE MAIN THEME OF THE FORECAST CONTINUES WITH ZONAL FLOW STILL BEING EXPECTED ACROSS MUCH OF THE NORTHEAST THROUGH THE FORECAST PERIOD. BY SAT NIGHT A WARM FRONT WILL HAVE JUST PASSED TO THE NORTH OF THE CWA AND A COLD FRONT WILL BE STARTING TO APPROACH THE REGION FROM THE WEST. THIS COLD FRONT WILL BRING COOLER AIR TO THE REGION ALONG WITH A CHANCE FOR RAIN/AND OR SNOW SHOWERS TO NEW YORK AND PENNSYLVANIA. A SFC RIDGE WILL THEN START TO BUILD OVER THE AREA FROM THE WEST MONDAY AFTERNOON... THUS BRINGING DRY AND QUIET WEATHER BACK TO THE AREA THROUGH MID WEEK. THIS RIDGE WILL ALSO ALLOW TEMPERATURES OVER THE REGION TO FALL BELOW THE SEASONAL NORM. THE COLDEST DAY IN THE EXTENDED FORECAST WILL BE WHEN THE RIDGE IS EXPECTED TO BE CENTERED OVER THE CWA. THIS WILL OCCUR ON TUESDAY. HIGH TEMPERATURES ARE EXPECTED TO RISE INTO THE LOW TO MID 30S. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... A LARGE WINTER STORM WILL PRODUCE WIDESPREAD IFR VSBYS AT ALL TERMINALS THROUGH THIS EVENING. THE HEAVIEST SNOW WILL FALL THROUGH THIS AFTERNOON AND FALL FROM NEAR KBGM EXTENDING EAST AND SOUTH. AS A RESULT, VISIBILITIES BELOW AIRPORT MINIMUMS CAN BE EXPECTED FOR KBGM AND KAVP AT TIMES THIS AFTERNOON. CONDITIONS WILL START TO IMPROVE THIS EVENING AS THE HEAVIEST PRECIP LIFTS NORTH AND EAST ALTHOUGH WE DON`T EXPECT CONDITIONS TO IMPROVE ABOVE IFR UNTIL AROUND MIDNIGHT DUE TO LINGERING LIGHT SNOW. EXPECT MVFR CEILINGS/VISBYS TO LINGER THROUGH TONIGHT IN SCATTERED SNOW SHOWERS FOR ALL SITES EXCEPT KELM AND KAVP. OUTLOOK... THU/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY KSYR-KRME. SUN...RESTRICTIONS POSSIBLE FROM -SHRA. MON...RESTRICTIONS POSSIBLE FROM -SHRA/SHSN. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR PAZ038>040- 043-044-047-048-072. NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ045-046- 055>057-062. WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NYZ009-017- 018-024-025-036-037-044. && $$ SYNOPSIS...MLJ NEAR TERM...MLJ SHORT TERM...MLJ LONG TERM...KAH AVIATION...PCF
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1236 AM EST WED NOV 26 2014 .SYNOPSIS... A STORM SYSTEM MOVING ALONG THE EAST COAST WEDNESDAY INTO THURSDAY MORNING WILL IMPACT ALL OF NORTHEAST PENNSYLVANIA AND A LARGE PART OF CENTRAL NEW YORK WITH A SIGNIFICANT SNOWFALL. THE HEAVIEST SNOW IS EXPECTED FROM THE POCONOS TO THE WESTERN CATSKILLS. SNOW WILL DEVELOP LATE TONIGHT AND LAST THROUGH WEDNESDAY AND TAPER OFF TO SNOW SHOWERS WEDNESDAY NIGHT AND EARLY THURSDAY. SNOWFALL OF 5 TO 12 INCHES IS EXPECTED FROM NORTHEAST PENNSYLVANIA TO THE CATSKILLS WITH 2 TO 6 INCHES TO THE NORTH AND WEST. LESS THAN 2 INCHES OF SNOW IS EXPECTED ACROSS THE NORTHERN FINGER LAKES REGION TO THE SYRACUSE AREA. && .NEAR TERM /THROUGH TODAY/... 8 PM UPDATE... L/WV TROF IS MVG THRU MS VLY AT THIS TIME WITH STRONG S/WV ROUNDING BASE OF TROF OVR LWR MS RVR. CYCLOGENESIS UNDERWAY ACRS NE GOM WITH PCPN NOW BEING REPORTED AS FAR NORTH AS THE PIEDMONT OF NC. LATEST MODELS HV TRENDED JUST A TAD SLOWER WITH PCPN EXPECTED TO MV INTO CWA CLOSER TO 12Z. RUC AND HIRES ARW SEEM TO HV BEST HANDLE ON PCPN AS OF 00Z AND NOT SHOWING MUCH IN THE WAY OF ECHOES MVG INTO POCONOS UNTIL 11Z AT THE EARLIEST. AS PCPN HEADS NORTH EXPECTING TO SEE JUST A WALL OF SNOW HEADING AT US. THUS HV GONE FM LOCHC POPS TO CATEGORICAL DRG THE MRNG HRS. 18Z NAM HAS TRENDED A TAD WETTER AND FURTHER WEST WITH PCPN WITH 24-HR AMNTS OVR 1+ INCHES OVR FAR SE ZONES AND 0.75 INCHES AS FAR WEST AS AN ELMIRA-UTICA LINE. WL EVALUATE 00Z GUIDANCE COMING IN AND POSSIBLY EXPAND WARNINGS/ADVISORIES FURTHER WEST OVRNGT. FOR NOW, HV LWRD SNOW AMNTS BTWN 06Z AND 12Z OVR NEPA AND ADJUSTED AMNTS HIGHER FOR THE 12Z-18Z TIMEFRAME AS THIS LOOKS TO BE PRIMETIME. CONCERN IS THAT MESOSCALE BANDING WL SET UP JUST A HAIR FURTHER WEST LATE MRNG OR EARLY AFTN THAN MODELS ARE INDICATING. TREMENDOUS VERTICAL MOTION EXPECTED LATE MRNG INTO THE AFTN HRS IN AREA OF ENHANCE UPWARD DIFFLUENCE AS CWA WL LKLY BE IN RRQ OF H2 JET. NO OTHER ADJUSTMENTS NEEDED AT THIS TIME. PREV DISCUSSION BLO... ISSUED WINTER STORM WARNINGS FOR MOST OF NORTHEAST PENNSYLVANIA AND THE WESTERN CATSKILLS IN LINE WITH NEIGHBORING OFFICES AND BASED ON THE LATEST MODEL GUIDANCE WWD AND MODEL QPFS. MODELS ALL INDICATE THAT CYCLOGENESIS BEGINS ALONG THE EAST COAST WEDNESDAY INTO WEDNESDAY NIGHT AS A STRONG UPPER LEVEL WAVE ROUNDS THE BASE OF THE UPPER LEVEL TROUGH OVER THE EASTERN UNITED STATES. THE STORM WILL NOT CLOSE OFF AT 700 MB UNTIL IT IS NORTHEAST OF THE REGION AS THE SYSTEM GETS CAUGHT UP IN THE STRG SWRLY FLOW ALOFT. THIS WILL LEAD TO LESS LINGERING WRAP ARND ACCUMULATIONS THAT WE OFTEN SEE IN C NY/NRN PA. BASICALLY THIS SYSTEM WILL RUN INTO UPPER CONFLUENCE OVER THE MARITIMES BY THURSDAY AND SHEAR OUT. BUT IN THE PROCESS SIGNIFICANT WARM CONVEYOR BELT MOISTURE IS RUNNING INTO THE UPPER DIFFLUENCE OF THE RIGHT ENTRANCE REGION OF THE UPPER JET OVER SERN CANADA. THIS IS FAVORABLE FOR A SWATH OF HEAVY SNOW. MODELS ARE SHOWING THAT THE HEAVIEST SNOW IN OUR FORECAST AREA IS FROM NE PA TO DELAWARE/SULLIVAN CO/S IN NY. CROSS SECTIONS NORMAL TO THE THICKNESS ACROSS NE AND C NY SHOW A CLASSIC SLOPED LAYER OF FGEN FORCING WED PM WITH LOW STATIC STABILITY ABOVE OR EVEN WEAKLY UNSTABLE ALOFT. THIS IS A RECIPE FOR MESOSCALE SNOW BANDS AND BELIEVE A BAND OF HEAVY SNOW WILL FORM SOMEWHERE IN OUR WARNING AREA. IN GRIDS HAVE MENTION OF HEAVY SNOW IN THIS AREA. I ALSO AM CONCERNED THAT THIS BAND COULD TRACK FARTHER WEST AS IS OFTEN THE CASE AND IMPACT OUR ADVY AREA. THE 12Z EURO NOW HAS MORE QPF FARTHER WEST TOO. FOR NOW HAVE A ROW OF WINTER WX ADVY/S AS A BUFFER ZONE FROM TOWANDA TO BINGHAMTON TO COOPERSTOWN AND NORWICH. THIS AREA COULD GET INTO SOME HEAVY SNOW. IT DEPENDS ON WHERE THIS MESOSCALE BAND SETS UP. LATER SHIFTS WILL HAVE TO MONITOR. OUR BRIEFINGS WILL MENTION THE CHANCE THAT SOME HEAVIER SNOW COULD FALL FARTHER WEST. FOR THE REST OF WEDNESDAY NIGHT...SNOW WILL RAPIDLY TAPER DOWN TO SNOW SHOWERS FROM SW TO NE AS THE STORM PULLS TO THE NORTHEAST. && .SHORT TERM /TONIGHT THROUGH FRIDAY NIGHT/... 300 PM EST UPDATE... CAA WILL CONTINUE TO TAKE PLACE ACROSS THE CWA THURS AS THE SFC LOW MOVES FURTHER NORTH ALONG THE EAST COAST. THIS WILL ALLOW COOLER AIR TO MOVE INTO PORTIONS OF NY AND PA. THIS WILL RESULT IN THURS BEING FAIRLY COLD WITH TEMPERATURES ONLY RISING INTO THE LOW TO MID 30S. EVEN THOUGH THE POTENT STORM THAT HAVE CAUSED WARNINGS ACROSS THE EAST WILL BE WELL TO THE NORTH BY THURS... THIS DOES NOT MEAN AN END TO SNOW SHOWERS OVER THE CWA. THE CHANCE FOR SNOW ACROSS OUR AREA WILL STILL CONTINUE. SCATTERED SNOW SHOWERS WILL STILL BE POSSIBLE THROUGH THE DAY ON THURSDAY. THESE SNOW SHOWERS WILL BE THE RESULT FROM AN ALBERTA CLIPPER PASSING THROUGH. THESE SHOWERS ARE EXPECTED TO TO BE LIGHT AND SCATTERED IN NATURE. SOME LAKE EFFECT ACTIVITY WILL BE POSSIBLE BEHIND THE PASSAGE OF THE CLIPPER. THE BEST CHANCE FOR LE SNOW SHOWERS WILL BE SHORTLY AFTER 00Z FRIDAY THROUGH 00Z SATURDAY. TEMPS WILL BE A FEW DEGREES COOLER ON FRIDAY ACROSS MUCH OF THE AREA AS A VERY COLD AIRMASS WILL REMAIN OVER NY AND PA. SHOWERS ARE EXPECTED TO SLOWLY DIMINISH FRIDAY NIGHT. && .LONG TERM /SATURDAY THROUGH TUESDAY/... 300 PM EST UPDATE... HAVE MADE MINOR ADJUSTMENTS TO THE PREVIOUS FORECAST AND CLOSELY FOLLOWED WPC GUIDANCE. THE FLOW ALOFT WILL REMAIN ZONAL ACROSS MUCH OF THE EASTERN CONUS THROUGH THE FORECAST PERIOD. BUT SADLY THIS DOES NOT MEAN THE WX PATTERN WILL REMAIN QUIET THROUGH THE EXTENDED. THERE APPEARS TO BE A CHANCE FOR EITHER SNOW OR RAIN THROUGH THE EXTENDED. A WEAK LOW PRESSURE SYSTEM WILL FORCE A WARM FRONT ACROSS THE REGION EARLY SAT THEN SLOWLY BRING A COLD FRONT ACROSS THE CWA ON SUNDAY. GUIDANCE IS UPON FAIRLY GOOD AGREEMENT ON KEEPING THE SFC LOW WELL TO THE NORTH OF THE CWA. GUIDANCE HINTS AT HIGH PRESSURE BUILDING STARTING TO BUILD OVER REGION ON MONDAY. THIS MAY BRIEFLY HALT THE CHANCE FOR SHOWERS OVER THE REGION EARLY NEXT WEEK. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... A LARGE WINTER STORM WILL PRODUCE WIDESPREAD IFR VSBYS AT ALL TERMINALS WEDNESDAY. TIMING OF SNOW LOOKS TO BE BETWEEN 12Z AND 15Z SOUTHERN TERMINALS, AND AFTER 15Z UP NORTH. AIRPORT MINS WILL BE APPROACHED AT KBGM/KAVP A FEW HOURS AFTER THE ONSET OF THE SNOW, THROUGH THE END OF THE TAF PERIOD. FARTHER NORTH AND WEST FROM KELM TO KITH, KSYR, AND KRME IFR VSBYS LIKELY BUT NOT AS LOW AS FARTHER SOUTH. VSBYS WILL TEND TO RISE AFTER 00Z AS THE SYSTEM BEGINS TO LIFT OUT OF THE AREA. XPCT CIGS AND VSBY GNRLY IN THE MVFR RANGE THRU THE END OF THEPD...AS WINDS BECOME MORE NWLY BHD THE STORM. OUTLOOK... WED NGT...COASTAL SYSTEM MAY IMPACT REGION WITH RESTRICTIONS FROM SNOW...BEST CHANCE KAVP. THU/FRI/SAT...POSSIBLE RESTRICTIONS FROM SCT -SHSN...ESPECIALLY KSYR-KRME. SUN...RESTRICTIONS POSSIBLE FROM -SHRA. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR PAZ039-040- 043-044-047-048-072. WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR PAZ038. NY...WINTER STORM WARNING UNTIL 6 AM EST THURSDAY FOR NYZ057-062. WINTER WEATHER ADVISORY UNTIL 6 AM EST THURSDAY FOR NYZ045-046- 055-056. && $$ SYNOPSIS...DJN NEAR TERM...DJN/PVF SHORT TERM...KAH LONG TERM...KAH AVIATION...DGM/HEDEN
AREA FORECAST DISCUSSION
NWS RALEIGH NC
719 PM EST THU NOV 27 2014 .SYNOPSIS...AN UPPER LEVEL DISTURBANCE OVER THE REGION WILL SHIFT EAST AND AWAY FROM THE AREA THIS EVENING. HIGH PRESSURE WILL BUILD OVER THE REGION FROM THE WEST TONIGHT THROUGH EARLY SATURDAY... BEFORE PUSHING EAST OFF THE COAST LATE SATURDAY THROUGH SUNDAY. && .NEAR TERM /THROUGH FRIDAY NIGHT/... AS OF 215 PM THURSDAY... THROUGH TONIGHT: THE NORTHERN TWO-THIRDS OF THE CENTRAL NC HAVE HAD A VARIABLY CLOUDY... SOMEWHAT CHILLY... AND OCCASIONALLY SHOWERY THANKSGIVING DAY SO FAR... THANKS TO PASSAGE OF A COUPLE OF SHORTWAVE TROUGHS... THE SECOND OF WHICH IS NOW TRACKING EASTWARD INTO THE WRN CAROLINAS. MESOANALYSES AND RAP SOUNDINGS SHOW MINOR AMOUNTS OF CAPE... DUE TO FAIRLY STEEP 850-500 MB LAPSE RATES OF 6.5- 7.5 C/KM... AUGMENTING THE DYNAMIC FORCING FOR ASCENT. WILL MAINTAIN SCATTERED SHOWERS OVER THE AREA FOR ANOTHER FEW HOURS... ENDING LAST IN THE NE CWA BY VERY EARLY EVENING. AS THE SHORTWAVE TROUGH HEADS TO OUR EAST... A DRYING AND STABILIZING COLUMN WILL ENSUE FROM WEST TO EAST... YIELDING CLEARING SKIES AREAWIDE DURING THE EARLY-MID EVENING. CLEAR SKIES AND DIMINISHING WINDS ARE EXPECTED OVERNIGHT WITH RISING HEIGHTS... DOWNSLOPE-DIRECTED LOW LEVEL FLOW... AND HIGH PRESSURE BEGINNING TO BUILD IN FROM THE WEST. BASED ON LOCAL RESEARCH USING HISTORIC MIN TEMPS... LOW LEVEL THICKNESSES DROPPING TO AROUND 1280 M WOULD SUGGEST LOWS IN THE LOWER 20S... HOWEVER WITH THE MSLP GRADIENT STAYING UP ENOUGH TO ALLOW FOR A SLIGHT NW BREEZE OVERNIGHT LIMITING RADIATIONAL COOLING SOMEWHAT... WILL STICK WITH LOWS IN THE MID-UPPER 20S... CONSISTENT WITH STATISTICAL GUIDANCE. FOR FRI/FRI NIGHT: A QUIET DAY AND NIGHT WITH HIGH PRESSURE BUILDING OVERHEAD AND STRONGLY SUBSIDING MID LEVELS. EXPECT LOTS OF SUNSHINE DURING THE DAY. THE THERMAL TROUGH LIFTS OUT DURING THE LATTER HALF OF THE DAY... AND THICKNESSES ACCORDINGLY REBOUND CONSIDERABLY (ALTHOUGH THIS 1000-850 MB LAYER GRABS SOME OF THE WARMER AIR ABOVE THE SUBSIDENCE INVERSION). USING A LOW LEVEL DRY ADIABATIC PROFILE TO 925 MB INDICATES HIGHS OF 42-46... A SLIGHT LEAN TO THE COOL SIDE OF GUIDANCE AND IN LINE WITH EARLIER FORECAST HIGHS. THE SURFACE RIDGE SHOULD BE OVERHEAD EARLY FRI NIGHT BUT SHIFTING EASTWARD LATE... SO WINDS SHOULD BE FAIRLY LIGHT WITH GENERALLY CLEAR SKIES... ALTHOUGH WE`LL SEE INCREASING HIGH CLOUDS LATE AS MINOR WAVES TRACK ESE INTO NC WITHIN THE FAST STEERING FLOW ALOFT. STILL EXPECT LOWS IN THE MID-UPPER 20S. -GIH && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 245 PM THURSDAY... HIGH PRESSURE WILL SHIFT OFFSHORE DURING THE DAY ON SATURDAY... ALLOWING RETURN FLOW TO FIRMLY SET UP OVER THE REGION FOR THE WEEKEND. IN ADDITION...MID LEVEL RIDGING WILL BUILD NORTH AND EAST ACROSS THE AREA. ALL OF THIS WILL LEAD TO FAIR WEATHER AND A WARMING TREND...WITH HIGHS EXPECTED TO BE IN THE LOW TO MID 50S ON SATURDAY AND THEN LOW TO MID 60S BY SUNDAY. OVERNIGHT LOWS WILL ALSO MODERATE THROUGH THE PERIOD...WITH MOSTLY MID/UPPER 30S SATURDAY NIGHT AND THEN MID/UPPER 40S SUNDAY NIGHT. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 245 PM THURSDAY... A NORTHERN STREAM SHORT WAVE MOVING ALONG THE US/CANADIAN BORDER WILL SUPPRESS THE MID LEVEL RIDGE TO THE SOUTH AS IT PROPELS A SURFACE FRONT TOWARDS THE REGION EARLY NEXT WEEK. THIS TRAILING COLD FRONT IS STILL PROGGED TO CROSS THE AREA MONDAY NIGHT INTO TUESDAY. FORCING IS NOT THAT IMPRESSIVE WITH THIS SYSTEM GIVEN THE PARENT LOW IS SO FAR NORTH OF THE AREA. HOWEVER...GIVEN SOME CONVERGENCE AND MOISTURE POOLING ALONG THE BOUNDARY...WILL MAINTAIN SLIGHT CHANCE POPS IN THE FORECAST. HIGHS WILL WARM UP NICELY WITHIN THE DEEP SOUTHWESTERLY FLOW AHEAD OF THE FRONT...WITH MID TO UPPER 60S (NEAR 70 DEGREES ACROSS THE SOUTHEAST) EXPECTED. TEMPS WILL BE COOLER BEHIND THE FRONT ON TUESDAY...WITH HIGHS GENERALLY IN THE UPPER 40S TO MID/UPPER 50S (COOLEST IN THE NORTHWEST WHERE SOME CAD MAY DEVELOP). QUITE A BIT OF UNCERTAINTY THEN PERSISTS FOR THE REMAINDER OF THE FORECAST PERIOD AS ANOTHER SYSTEM (POSSIBLY) APPROACHES FROM THE NORTHWEST. THE ECMWF IS MUCH MORE AMPLIFIED/PROGRESSIVE WITH ANOTHER SHORT WAVE SWINGING THROUGH THE AREA WEDNESDAY INTO THURSDAY...WILL THE GFS IS MUCH LESS AMPLIFIED (WITH ZONAL FLOW ACTUALLY OVER THE MID ATLANTIC REGION). GIVEN THE DIFFERENCES...WILL KEEP ANY POPS LOW...WITH SEASONAL HIGHS/LOWS. && .AVIATION /00Z FRIDAY THROUGH TUESDAY/... AS OF 719 PM THURSDAY... SCATTERED SHOWER ACTIVITY FROM THIS AFTERNOON HAS STEADILY DIMINISHED AFTER SUNSET. DRY WEATHER WITH VFR CONDITIONS WILL PREVAIL OVER THE NEXT 24 HOURS. WINDS WILL CONTINUE TO BE LIGHT AND FROM THE NORTHWEST AT 5-10 KTS AS HIGH PRESSURE BUILDS INTO THE SOUTHEAST STATES. LOOKING BEYOND 18Z FRI... VFR CONDITIONS ARE EXPECTED TO DOMINATE THROUGH MON... ALTHOUGH AREAS OF MVFR OR IFR FOG ARE POSSIBLE EARLY SUN MORNING AND EARLY MON MORNING. HIGH PRESSURE WILL SHIFT EASTWARD OVER THE REGION THROUGH SAT... THEN MOVE EAST AND OFFSHORE SAT NIGHT/SUN. A COLD FRONT WILL MOVE IN FROM THE NORTH LATE MON OR MON NIGHT... BRINGING A GOOD CHANCE OF MVFR/IFR CONDITIONS MON NIGHT/TUE AND PATCHY LIGHT RAIN. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...KRD LONG TERM...KRD AVIATION...SEC/HARTFIELD
AREA FORECAST DISCUSSION
NWS WILMINGTON NC
1224 AM EST WED NOV 26 2014 .SYNOPSIS... RAIN WILL CONTINUE OVERNIGHT INTO WEDNESDAY MORNING AS LOW PRESSURE MOVES UP THE SOUTHEAST COAST. SKIES WILL CLEAR OUT BY THANKSGIVING DAY...WITH TEMPERATURES RUNNING SEVERAL DEGREES BELOW NORMAL INTO THE WEEKEND BEFORE WARMER TEMPERATURES RETURN FOR EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... AS OF 12:30 AM WEDNESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: SO FAR SO GOOD WITH THE EARLIER CHANGES TO QPF AMOUNTS. WITH THE EXCEPTION OF A NARROW BAND OVER WILMINGTON WHICH IS DROPPING FAIRLY HEAVY RAIN NOW...RATES ARE 0.05 INCHES PER HOUR OR LESS ACROSS THE BULK OF THE FORECAST AREA. RADAR COMPOSITES SOUTH TO THE FLORIDA GEORGIA LINE SHOW A SIZABLE GAP IN RAINFALL... PERHAPS KEEPING THOSE RED CLAY ROADS A LITTLE LESS MUDDY THAN THEY OTHERWISE MIGHT BE. DEEP CONVECTION CONTINUES ACROSS CENTRAL FLORIDA AND OFF THE FLORIDA EAST COAST AND THIS SHOULD CONTINUE TO NEGATIVELY IMPACT OUR PRECIPITATION INTENSITY FOR THE NEXT 3-5 HOURS. LATEST HRRR MODEL RUNS SHOW THE SYNOPTIC LOW MAY ACTUALLY MOVE INLAND BRIEFLY ACROSS SE NORTH CAROLINA AROUND 11-12Z WED. A TRACK THIS FAR WEST WOULD KEEP LOW TEMPERATURES IN WILMINGTON IN THE 60S DUE TO ONSHORE EASTERLY FLOW. I HAVE TWEAKED THE IMPLIED SYNOPTIC LOW TRACK A LITTLE CLOSER TO THE COAST...JUST NICKING BALD HEAD ISLAND BEFORE DAYBREAK. PREVIOUS DISCUSSION FROM 700 PM FOLLOWS... WE ARE ENTERING THE PERIOD OF WHAT SHOULD BE THE STRONGEST UPPER LEVEL DIVERGENCE AND LOW-TO-MID LEVEL ISENTROPIC LIFT NOW. 305K-310K ISENTROPIC LIFT FORECASTS FROM THE 18Z NAM OR GFS SUGGEST IT SHOULD BE POURING EVERYWHERE! HOWEVER THE BROAD-SCALE RADAR COMPOSITE SHOWS THE FORECAST PROBLEM FOR TONIGHT: WIDESPREAD DEEP CONVECTION ACROSS THE FLORIDA PENINSULA AND OFFSHORE EAST OF JAX IS PRODUCING DOWNSTREAM MID-LEVEL WARMING AND DRYING THAT IS NEGATIVELY IMPACTING PRECIPITATION COVERAGE ACROSS SOUTH GEORGIA AND THE CAROLINAS. THIS IS A CLASSIC PROBLEM WE SEE LOCALLY DURING THE COOL SEASON THAT HAS FRANKLY NEVER BEEN HANDLED WELL BY THE SYNOPTIC MODELS. BOTH THE HRRR AND HRRRX (AN EXPERIMENTAL VERSION AVAILABLE ON THE RAPID REFRESH.NOAA.GOV SERVER) ARE INITIALIZING WITH THE CORRECT "HOLE" IN THE PRECIPITATION SHIELD AND SHOW THIS ANOMALY MAY CONTINUE TO PLAGUE THE REGION`S RAINFALL FORECAST THROUGH THE NIGHT. THE 18Z SYNOPTIC RAINFALL GUIDANCE FROM WPC ALSO SEEMS TO AGREE WITH THIS IDEA OF LESSER RAINFALL TOTALS THAN ORIGINALLY THOUGHT. WITH THIS IN MIND I HAVE KEPT FORECAST POPS AT 100% (EVERYONE WILL GET AT LEAST 0.01 INCHES OF RAIN) BUT I HAVE TRIMMED BACK FORECAST RAINFALL AMOUNTS SUBSTANTIALLY. FROM RIGHT NOW THROUGH THE END OF THE EVENT LATE WEDNESDAY MORNING IT APPEARS TOTALS SHOULD AVERAGE HALF OF AN INCH...PERHAPS APPROACHING AN INCH ALONG THE COAST IF RAINFALL RATES CAN INCREASE TOWARD THE END OF THE EVENT WEDNESDAY MORNING. OVER THE PAST FEW DAYS SYNOPTIC GUIDANCE HAS TRENDED FARTHER WEST WITH THE FORECAST PATH OF THE LOW MOVING NORTH FROM FLORIDA. 18Z MODELS CONTINUED THIS TREND AND I HAVE SHIFTED THE IMPLIED TRACK OF THE LOW IN THE FORECAST WIND GRIDS TO ONLY ABOUT 10 MILES EAST OF CAPE FEAR LATE TONIGHT. THIS WILL HAVE THE ADDED IMPACT OF MAINTAINING A WARMER AIRMASS NEAR THE COAST...PARTICULARLY SE NORTH CAROLINA...AND I HAVE RAISED FORECAST LOWS BY SEVERAL DEGREES HERE. FARTHER INLAND THE COLD AIR SHOULD BEGIN TO BLEED IN FROM THE NW SHORTLY AND VERY FEW CHANGES WERE NEEDED TO THE OVERALL TEMP/WIND FORECAST. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... AS OF 300 PM TUESDAY...LOW PRESSURE HUGGING THE COAST WILL BE MOVING N OF THE WATERS WEDNESDAY MORNING. AS THE LOW MOVES UP THE NORTH CAROLINA AND MID ATLANTIC COAST WED...THE RAIN WILL SHUT OFF FROM SSW TO NNE. PERIODS OF HEAVY RAIN ARE STILL POSSIBLE WED MORNING...BUT EXPECT BY AFTERNOON...THE RISK FOR RAINFALL WILL HAVE ENDED ACROSS ALL BUT THE CAPE FEAR AREA WHERE A SLIGHT RISK OF AFTERNOON RAIN WILL STILL BE POSSIBLE. WILL INCLUDE CATEGORICAL POPS WED MORNING THROUGHOUT. CONVECTION IS EXPECTED TO STAY OFFSHORE... EAST OF THE LOW CENTER WHERE THERE WILL BE AN INFLUX OF WARMER AND MORE UNSTABLE AIR. ONE VERY POTENT MID-LEVEL SHORTWAVE TROUGH WILL PIVOT ACROSS THE FORECAST AREA WED AFTERNOON WHILE ANOTHER SKIRTS OUR FORECAST AREA TO THE N LATE WED NIGHT AND THU MORNING BEFORE LIFTING OUT. THE INFLUX OF COLDER AND DRIER AIR WORKING INTO THE EASTERN CAROLINAS ON THE BACKSIDE OF FIRST SHORTWAVE WILL HELP TO SIGNIFICANTLY DRY THE COLUMN WITH PRECIPITABLE WATER VALUES DROPPING TO LESS THAN HALF AN INCH. THIS WILL HELP TO PROMOTE DECREASING AFTERNOON CLOUDINESS... ESPECIALLY ACROSS SOUTHERN AND WESTERN ZONES. THE SECOND SHORTWAVE MAY ACTUALLY BRING A BRIEF INCREASE IN CLOUD COVER...BUT PRECIPITATION IS EXPECTED TO REMAIN TO OUR N. TEMPS ON WED WILL NOT MOVE MUCH AS COLD AIR ADVECTION GETS UNDERWAY. IN FACT HIGHS WILL BE ACHIEVED IN MANY CASES PRIOR TO OR AROUND SUNRISE. WE EXPECT HIGHS TO BE IN THE LOWER TO MID 50S ON THE COAST WITH UPPER 40S TO AROUND 50 FROM EYF TO HYW AND POINTS W. DAYTIME TEMPS WILL HOLD STEADY OF NOT DROP A DEGREE OR TWO. TEMPS WED NIGHT WILL DROP INTO THE 30S TO AROUND 40. EVEN THE COLDEST SPOTS SHOULD NOT REACH THE FREEZING MARK GIVEN THE LACK OF RADIATIONAL COOLING. CHILLY HIGH PRESSURE WORKING TO THE COAST FROM THE W WILL ALLOW THE PRESSURE GRADIENT TO LOOSEN THU NIGHT. THE COOLEST TEMPS AT 850 MB THU WILL BE OFFSET BY SUNSHINE AND WE DO EXPECT HIGHS TO STILL REACH THE MID 50S. RADIATIONAL COOLING WILL DEVELOP THU NIGHT WHICH SHOULD ALLOW LOWS TO DROP INTO THE UPPER 20S TO LOWER 30S OVERNIGHT. && .LONG TERM /FRIDAY THROUGH TUESDAY/... AS OF 300 PM TUESDAY...LONG TERM PERIOD WILL REMAIN DRY WITH MID LEVEL FLOW BECOMING PROGRESSIVE. COLD ADVECTION WILL BE WINDING DOWN FRI...BUT TEMPS STILL END UP WELL BELOW CLIMO. DEEP WESTERLY FLOW WILL BE QUICK TO SHIFT THE CENTER OF THE MODIFYING HIGH OFF THE COAST WITH RETURN FLOW DEVELOPING SAT. TEMPS REMAIN BELOW CLIMO SAT BUT WILL BE WARMER THAN FRI. EARLY NEXT WEEK 5H RIDGE TRIES TO BUILD NORTH FROM THE EASTERN GOMEX AND FL. BUILDING HEIGHTS AND INCREASING SOUTHWEST FLOW EARLY NEXT WEEK WILL PUSH TEMPS ABOVE CLIMO. BACKDOOR COLD FRONT DEPICTED IN MEDIUM RANGE GUIDANCE YESTERDAY NOW LOOKS TIMED TO CROSS THE AREA TUE MORNING...WITH BOTH GFS/ECMWF IN DECENT AGREEMENT. FRONT WILL PASS DRY FOLLOWED BY WEAK COLD ADVECTION WITH TEMPS DROPPING BACK NEAR CLIMO. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... AS OF 06Z...EXPECT MAINLY IFR/LIFR CIGS TO PREVAIL DURING THE EARLY MORNING HOURS WITH RAIN CONTINUING TO FALL ACROSS THE AREA. VSBYS WILL BE REDUCED TO MVFR LEVELS IN PATCHES OF HEAVIER PCPN. ALTHOUGH A BRIEF LULL IN RAINFALL IS POSSIBLE BEFORE DAYBREAK...MORE SHOULD SPREAD OVER OUR CWA THIS MORNING AS LOW PRESSURE RIDES UP THE COAST ALONG A STALLED FRONT OFFSHORE. EAST-NORTHEAST WINDS AROUND 10 KT WILL BECOME NORTHWEST AND GUSTY BY 12Z AS THE LOW SKIRTS OUR COAST. THE ENHANCED GRADIENT WILL RESULT IN NORTHWEST WINDS 15-20 KT DURING THE MORNING/EARLY AFTERNOON HOURS. IFR CIGS WILL GRADUALLY LIFT TO MVFR THROUGH THE MORNING. AFTER 18Z...RAIN WILL DIMINISH AND DRIER W-NW FLOW WILL PROMOTE FURTHER CLEARING ON THE BACK SIDE OF THE LOW. ALL TAF SITES SHOULD BE VFR BY 00Z THU AS WEST WINDS DIMINISH TO 5 KT. EXTENDED OUTLOOK...VFR CONDITIONS EXPECTED THURSDAY THROUGH SUNDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 12:30 AM WEDNESDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: LATEST HRRR MODEL RUNS SHOW THE LOW TRACKING A BIT FARTHER WEST THAN THE AFTERNOON MODELS INDICATED. I HAVE TWEAKED THE IMPLIED TRACK OF THE LOW ANOTHER 5 MILES WEST IN THE LATEST GRIDDED WIND FORECAST...JUST NICKING BALD HEAD ISLAND BEFORE DAYBREAK. THIS WOULD BRING SOUTHERLY WINDS ACROSS MOST OF THE COASTAL WATERS NORTH OF CAPE FEAR LATE TONIGHT. OTHERWISE FEW CHANGES WERE NEEDED TO THE FORECAST THIS EVENING. PREVIOUS DISCUSSION FROM 700 PM FOLLOWS... THE CAROLINA COASTAL WATERS ARE IN A LULL CURRENTLY AS LOW PRESSURE DEVELOPS ALONG A FRONT STALLED ACROSS THE FLORIDA PENINSULA. THIS FRONT EXTENDS NORTHEASTWARD TO VERY NEAR CAPE FEAR WHICH EXPLAINS THE WEAK PRESSURE GRADIENT WE SEE ON SURFACE CHARTS. AS THE NIGHT PROGRESSES THE LOW SHOULD FOLLOW THE FRONT NORTH-NORTHEASTWARD...GRADUALLY DEEPENING AND PASSING JUST EAST OF CAPE FEAR BEFORE DAYBREAK WEDNESDAY MORNING. WITH THE FRONT REMAINING JUST OFF THE COAST WE SHOULD NOT SEE VERY STRONG WINDS ACROSS THE COASTAL WATERS TONIGHT...15 KNOTS OR LESS THROUGH EARLY WEDNESDAY MORNING. THE EXCEPTION TO THIS MAY BE ACROSS THE WATERS 10-20 MILES EAST OF CAPE FEAR WHERE STRONG SOUTH WINDS DEVELOPING AROUND MIDNIGHT AHEAD OF THE INTENSIFYING LOW COULD REACH 25 KNOTS. CERTAINLY OFFSHORE BEYOND 20 MILES WINDS ARE GOING TO INTENSIFY QUITE A BIT OVER THE NEXT 6 HOURS AHEAD OF THE LOW. THIS WILL BE IMPORTANT SINCE SEAS WILL BUILD QUITE SUBSTANTIALLY OFFSHORE...AND A GOOD DEAL OF SOUTHERLY SWELL ENERGY SHOULD PROPAGATE INTO THE COASTAL WATERS BEGINNING LATE THIS EVENING. FOR THIS REASON THE SMALL CRAFT ADVISORY WILL REMAIN IN EFFECT FOR THESE 4-6 FOOT SEAS DEVELOPING AFTER MIDNIGHT. SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/... AS OF 300 PM TUESDAY...SMALL CRAFT ADVISORY CONDITIONS WILL CONTINUE THROUGH THE DAY WED. WE DO THINK THESE CONDITIONS MAY WANE WED EVE. HOWEVER...IT IS POSSIBLE THAT SMALL CRAFT ADVISORY CONDITIONS REDEVELOP FOR A TIME LATE WED NIGHT AND THU AS BACKSWELL FROM COASTAL LOW PRESSURE WELL NORTH OF THE AREA WORKS DOWN THE COAST. ALSO...THE PRESSURE GRADIENT BETWEEN HIGH PRESSURE TO OUR W AND COASTAL LOW WILL HELP TO INCREASE LOW-LEVEL WIND SPEEDS AS SURGE OF COLDEST AIR ARRIVES ACROSS THE WATERS. THE WIND DIRECTION WILL BE NW OR TRANSITIONING TO NW WED MORNING AS THE LOW MOVES FURTHER UP THE COAST. THE DIRECTION WILL THEN BACK TO A MORE WESTERLY DIRECTION WED NIGHT AND THU. AS HIGH PRESSURE TO THE W BEGINS TO ASSERT ITSELF LATE THU AND THU NIGHT...THE WIND DIRECTION WILL VEER TO NW AND THEN N. HIGHEST WIND SPEEDS THIS PERIOD WILL BE UP TO 20 TO 25 KT AND SEAS UP TO 5 TO 8 FT. LONG TERM /FRIDAY THROUGH SUNDAY/... AS OF 300 PM TUESDAY...DECREASING NORTHWEST FLOW ON FRI WILL BECOME LIGHT AND VARIABLE FRI NIGHT INTO SAT AS SURFACE RIDGE AXIS MOVES OVERHEAD. LIGHT SOUTHERLY FLOW DEVELOPS SAT AFTERNOON AS THE CENTER OF THE HIGH PUSHES EAST OF THE WATERS. GRADIENT BECOMES A LITTLE MORE DEFINED LATER SAT WITH SOUTHWEST FLOW INCREASING TO 10 TO 15 KT SAT NIGHT AND SUN. SEAS 2 TO 4 FT FRI MORNING DROP TO 2 TO 3 FT FRI NIGHT AND 2 FT OR LESS SAT AND SUN. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ250- 252-254-256. && $$ SYNOPSIS...RJD NEAR TERM...REK/RGZ SHORT TERM...RJD LONG TERM...III AVIATION...BJR MARINE...REK/RJD/III/RGZ
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
328 PM CST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY NIGHT) ISSUED AT 328 PM CST WED NOV 26 2014 FORECAST CHALLENGE FOR THE SHORT TERM WILL BE OVERNIGHT LOWS TONIGHT AS WELL AS TIMING AND AMOUNT OF SNOW THANKSGIVING NIGHT. A SURFACE HIGH WILL DROP INTO THE VALLEY TONIGHT AND BRING A VERY COLD AND DRY AIR MASS. THIS WILL RESULT IN OVERNIGHT LOWS WELL BELOW SEASONAL NORMS. A CLIPPER THEN MOVES INTO EASTERN MONTANA TOMORROW NIGHT AND A BAND OF SNOW IS EXPECTED TO FORM OVER PORTIONS OF CENTRAL AND EASTERN NORTH DAKOTA ON INTO NORTHWEST MINNESOTA. HAVE USED A BLEND OF NAM DNG AND HRRR FOR OVERNIGHT LOWS TONIGHT AND A MODEL BLEND FOR THE THANKSGIVING NIGHT SYSTEM AS THERE ARE STILL VARIATIONS ON THE PLACEMENT OF SNOW. TONIGHT...CURRENT VIS SATELLITE SHOWS CLEARING LINE HAS MADE IT AS FAR SOUTH OF I 94. DEW POINTS NORTH OF THIS MID CLOUD DECK ARE ALREADY 5 TO 10 BELOW AND IN THE MID TEENS BELOW ACROSS SOUTHERN MANITOBA. THE RIDGE AXIS EXTENDING OUT OF A HIGH OVER MANITOBA WILL BRING CALM WINDS TO THE DVL REGION EARLY IN THE EVENING...AND WITH A LIGHT COVERING OF FRESH SNOW THE TEMPS SHOULD QUICKLY DROP TO 5 TO 10 BELOW THIS EVENING. BY MORNING...RETURN FLOW SETS UP OVER THE DEVILS LAKE BASIN REGION UP THROUGH TOWNER/PEMBINA/CAVALIER COUNTIES. THIS WILL ALLOW WIND CHILLS TO DROP INTO THE 20 TO 25 BELOW RANGE TONIGHT...AND EVENING SHIFT WILL NEED TO MONITOR CLOSELY AS COLDER TEMPS WOULD BRING AREA INTO WIND CHILL ADVISORY CRITERIA (LESS THAN 25 BELOW ZERO). WARMEST TEMPS SHOULD BE ACROSS THE FAR SOUTH AS THE CURRENT MID CLOUDS WILL DELAY RADIATIONAL COOLING FOR AT LEAST A FEW HOURS THIS EVENING...BUT EXPECT THAT AREA TO CLEAR OUT BY 02Z TO 03Z. DEW POINTS ARE ABOUT 10 DEG HIGHER IN THIS REGION SO NOT LOOKING FOR AS SIGNIFICANT OF A DROP OFF. RIDGE AXIS SHOULD THEN BE OVER THE EAST TOMORROW MORNING AND TEMPS SHOULD DROP TO AROUND 10 BELOW. TOMORROW AND TOMORROW NIGHT...A VERY COLD START TO THE DAY WILL LIMIT DAYTIME HIGHS DESPITE SOME SOLAR IN THE MORNING BEFORE WE SEE INCREASING CLOUDS FROM WEST TO EAST TOMORROW AFTERNOON. TEMPS WILL STRUGGLE TO BREAK 10 ABOVE. BAND OF SNOW ASSOCIATED WITH WARM ADVECTION AND ISENTROPIC LIFT WILL SET UP OVER WESTERN ND TOMORROW MORNING AND MOVE INTO CNTRL ND IN THE AFTN. A BAND OF ISENTROPIC LIFT INTENSIFIES AND MOVES INTO THE WESTERN CWA BETWEEN 00Z AND 06Z. NAM 280K ISENTROPIC SFC WINDS IN THE 20 TO 30 KT RANGE ARE DIRECTLY PERPENDICULAR TO THE PRESSURE GRADIENT AND SHOULD BE SUFFICIENT TO LIFT THE PARCEL ABOUT 100 MB...WITH NEARLY SATURATED CONDENSATION PRESSURE DEFICITS IN EASTERN NORTH DAKOTA. THERE IS STILL DIFFERENCES IN THE PLACEMENT OF THE SNOW...WITH ECMWF A BIT FURTHER SOUTH AND WEST THAN THE 18Z NAM AND 12Z GFS. HPC QPF GUIDANCE PREFERS THE SLIGHTLY NORTHWARD SOLUTION...AND HAVE UPDATED SNOW RATIOS TO YIELD 3 TO 4 INCHES IN NORTH OF THE DEVILS LAKE REGION DOWN THROUGH THE CENTRAL VALLEY. .LONG TERM...(FRIDAY THROUGH WEDNESDAY) ISSUED AT 328 PM CST WED NOV 26 2014 FRIDAY...SNOW SHOULD BEGIN TAPERING OFF FRIDAY MORNING BUT PORTIONS OF EASTERN NORTH DAKOTA TO INCLUDE THE NORTHERN VALLEY WILL HAVE ANOTHER TWO TO FOUR INCHES OF SNOW. MOTORISTS IN NORTHEASTERN NORTH DAKOTA CAN EXPECT LESS THAN DESIRABLE DRIVING CONDITIONS FOR BLACK FRIDAY SHOPPING...ESPECIALLY IN THE EARLY MORNING HOURS. ANOTHER SFC LOW ENTERS EASTERN MT FRI AFTN AND MOVES INTO THE DAKOTAS OVERNIGHT. MODELS CONTINUING TO DIFFER ON QPF AMOUNTS AND PLACEMENT OF THIS SECOND SHOT OF SNOW. GFS IS THE MOST BULLISH AND BRINGS SOUTHERN EDGE OF SNOW BAND DOWN TO THE HIGHWAY 2 CORRIDOR WHILE THE NAME IS FAIRLY DRY AND THE ECMWF KEEPS SNOW MAINLY NORTH OF INTL BORDER. DO TO MODEL INCONSISTENCY WILL USE CONTINUITY AS SOLUTION...WITH LOW CHANCE POPS ACROSS THE NORTHERN TIER OF COUNTIES. WILL LIKELY SEE A BREAK MID DAY BETWEEN THE TWO SNOW PRODUCING SYSTEMS SHOULD THE SNOW SET UP ALONG AND NORTH OF HWY 200...THE MOST LIKELY AREA FOR ADDITIONAL ACCUMULATION. DAYTIME HIGHS WILL BE WARMER ON FRIDAY AND JUMP INTO THE MID 20S ACROSS THE SOUTH. SATURDAY...GFS/ECMWF CONTINUE TO SHOW LINGERING SNOW SHOWERS ACROSS THE NORTH AS NW SFC FLOW SETS UP...WHILE THE NAM REMAINS DRY. WILL KEEP CONTINUITY FOR THIS PERIOD AS WELL...ALTHOUGH ANY SNOW ON SATURDAY SHOULD BE LIGHT WITH LITTLE ACCUMULATION. SATURDAY NIGHT THROUGH WEDNESDAY...MODELS START OUT IN FAIRLY DECENT AGREEMENT...PUSHING A POSITIVELY TILTED TROUGH THROUGH THE NORTHERN ROCKIES AND PLAINS OVER THE WEEKEND. THE COLD FRONT WILL MOVE THROUGH THE CWA SATURDAY NIGHT AND COLD HIGH PRESSURE WILL BE IN PLACE FOR SUNDAY. CONTINUED TO KEEP SOME 30ISH POPS FOR WHEN THE FRONTAL BOUNDARY PASSES...THEN DRYING OUT INTO THE EARLY PART OF THE WORK WEEK. TEMPS WILL AGAIN BE WELL BELOW AVERAGE WITH LOWS IN THE TEENS BELOW ZERO AND HIGHS IN THE SINGLE DIGITS ABOVE FOR SUNDAY AND MONDAY. MODEL CONSENSUS STARTS TO DIVERGE BY TUESDAY AND WEDNESDAY. THE GFS IS MORE ACTIVE AND BRING A VIGOROUS SHORTWAVE THROUGH THE NORTHERN PLAINS WITH SFC LOW PRESSURE JUST TO OUR NORTH AND THE CWA SHOWING SOME STRONG WARM AIR ADVECTION MONDAY AND EARLY TUESDAY BEFORE THE NEXT COLD FRONT COMES IN. THE ECMWF IS WEAKER AND DRIER. ENSEMBLE MEMBERS SHOW A GOOD AMOUNT OF SPREAD...SO FOR NOW KEPT ONLY MINIMAL POPS AS THE OPERATIONAL GFS IS ONE OF THE WETTER SOLUTIONS. TEMPS SHOULD SEE SOME WARMING ON TUESDAY AND COLDER AGAIN ON WEDNESDAY...BUT EVEN THE HIGHER TEMP DAYS WILL STILL BE BELOW SEASONAL AVERAGES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1258 PM CST WED NOV 26 2014 SOME MID LEVEL CLOUD CONTINUES TO LINGER ACROSS PORTIONS OF THE FORECAST AREA...BUT CONDITIONS WILL REMAIN VFR AND SKIES WILL CLEAR FROM NORTH TO SOUTH THROUGH THE REST OF THE AFTERNOON. NORTH WINDS WILL BECOME LIGHT AND VARIABLE OVERNIGHT AS HIGH PRESSURE MOVES OVER THE AREA. WILL HAVE TO WATCH FOR SOME PATCHY GROUND FOG FORMATION TOWARDS MORNING BUT DO NOT THINK AT THIS POINT WILL BE WIDESPREAD SO DID NOT INCLUDE IN TAFS. CLOUDS WILL BEGIN TO INCREASE IN THE WEST AND SOUTH WINDS BEGIN TO INCREASE LATE IN THE PERIOD AS THE NEXT SYSTEM APPROACHES BUT THINK ANY RESTRICTIONS TO CIGS AND VIS WILL BE AFTER THE TAF PERIOD. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...SPEICHER LONG TERM...JR/SPEICHER AVIATION...JR
AREA FORECAST DISCUSSION
NWS WILMINGTON OH
126 AM EST WED NOV 26 2014 .SYNOPSIS... HIGH PRESSURE WILL CONTINUE TO EXTEND INTO THE REGION INTO WEDNESDAY. A CLIPPER WILL PASS JUST SOUTH OF THE AREA WEDNESDAY NIGHT. HIGH PRESSURE WILL SLOWLY BUILD IN LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... FORECAST AREA WILL BE UNDER THE INFLUENCE OF SURFACE HIGH PRESSURE OVERNIGHT AS COASTAL STORM ORGANIZES OFF THE CAROLINA COAST. LATEST RAP AND NAM-WRF SUGGEST THAT INCREASING DIVERGENCE ALOFT FROM THE RIGHT REAR QUAD OF A STRONG UPR LVL JET COMBINED WITH MID LEVEL DEFORMATION WILL SPREAD PCPN NORTHWARD ON THE BACK SIDE OF THIS LOW ACROSS THE SRN AND CNTRL APPALACHIANS. THIS PCPN SHIELD SHOULD REMAIN JUST EAST/SOUTHEAST OF OUR FAR SE ZONES BY MORNING. MUCH OF THE AREA WILL BE MOSTLY CLOUDY DUE TO INCREASING MID LEVEL CLOUDINESS. THE NRN AND NWRN ZONES WILL BE CLOUDY AS LOW LEVEL MOISTURE REMAINS TRAPPED UNDERNEATH A SUBSIDENCE INVERSION WITH HIGH PRESSURE OVERHEAD. ALL IN ALL...THE FORECAST WILL REMAIN DRY...AND WITH PERSISTENT CLOUDS...TEMPERATURES WILL NOT FALL THAT MUCH FROM CURRENT READINGS. LOWS WILL RANGE FROM THE MID 20S NW TO THE LOWER 30S SE. && .SHORT TERM /6 AM THIS MORNING THROUGH THURSDAY NIGHT/... HIGH PRESSURE WILL GET PINCHED OFF BETWEEN LARGE LOW PRESSURE SYSTEM ON THE EAST COAST AND AN APPROACHING CLIPPER. SYNOPTIC MODELS SUGGEST THAT PRECIPITATION FROM THE FORMER COULD AFFECT FAR SOUTHEAST COUNTIES. HOWEVER HIGH RESOLUTION RUNS KEEP IT FURTHER AWAY FROM THE FORECAST AREA. HAVE OPTED TO CONTINUE WITH A DRY FORECAST FOR WEDNESDAY. COULD BE A GOOD DEAL OF CLOUD COVER THOUGH AS THERE IS SOME POTENTIAL FOR LOW CLOUDS TO REDEVELOP ACROSS PARTS OF THE AREA AND THEN HIGH CLOUDS FROM BOTH LOW PRESSURE SYSTEMS. CLIPPER WILL DIVE INTO SOUTHERN ILLINOIS BY WEDNESDAY EVENING AND THEN MAKE THE TURN EAST NEAR THE KENTUCKY-TENNESSEE BORDER. CANNOT RULE OUT SOME LIGHT SNOW OCCURRING ALONG AND SOUTH OF THE OHIO RIVER. BUT PROBABILITY CONTINUES TO LOOK RATHER LOW. IN THE WAKE OF THE CLIPPER A SECOND SHORT WAVE ON A MORE NORTHERLY TRACK WILL PASS ACROSS THE GREAT LAKES. ANY PRECIPITATION WITH THIS WILL STAY NORTH OF THE FORECAST AREA. BUT SURFACE WINDS WILL BRIEFLY BECOME FAVORABLE OFF LAKE MICHIGAN. SO THERE WILL BE A CHANCE OF SNOW SHOWERS IN THE NORTHERN COUNTIES. HIGH PRESSURE WILL FINALLY START TO BUILD IN THURSDAY NIGHT WITH CLOUDS DIMINISHING. FOR THE MOST PART USED A MOS BLEND FOR TEMPERA TUES WITH THE EXCEPTION OF WEDNESDAY NIGHT WHEN WARMER NUMBERS WERE FAVORED. && .LONG TERM /FRIDAY THROUGH TUESDAY/... SURFACE HIGH PRESSURE WILL BE CENTERED OVER THE OHIO VALLEY AND SOUTHEASTERN STATES ON FRIDAY MORNING. THE UPPER-LEVEL PATTERN WILL FEATURE WEST-NORTHWEST FLOW ACROSS A LARGE PORTION OF THE COUNTRY...WITH GRADUAL HEIGHT RISES OVER THE ILN FORECAST AREA. AN AREA OF WEAK ISENTROPIC LIFT WILL PASS THROUGH THE SOUTHERN GREAT LAKES AS WARM ADVECTION BEGINS ALOFT. FOR NOW...ANY PRECIPITATION (LIKELY TO FALL AS SNOW) APPEARS THAT IT WILL REMAIN ACROSS NORTHERN INDIANA AND NORTHERN OHIO. ALTHOUGH WARM ADVECTION WILL OCCUR AT THE SURFACE HEADING INTO SATURDAY...MODEL SOUNDINGS SUGGEST THAT AN INVERSION AND RELATIVELY THICK LAYER OF MOISTURE WILL KEEP THINGS FROM BECOMING WELL MIXED BELOW 5000 FEET. EVEN AS MOST OF THE COLUMN WILL REMAIN QUITE DRY...CLOUDY CONDITIONS WITH LOW CEILINGS APPEAR FAIRLY LIKELY...AND THERE IS EVEN WIDESPREAD MODEL AGREEMENT IN LIGHT PRECIPITATION BEGINNING BY SATURDAY EVENING (SOMEWHAT UNUSUAL FOR WHAT LOOKS LIKE A DRIZZLY PROFILE). WITH WARM ADVECTION AND PLENTIFUL CLOUD COVER...MIN TEMPERATURES FOR SATURDAY NIGHT / SUNDAY MORNING WERE INCREASED BY SEVERAL DEGREES FROM THE PREVIOUS FORECAST. CHANCES FOR PRECIPITATION WILL INCREASE HEADING INTO SUNDAY...AS FRONTOGENESIS OCCURS OVR THE OHIO VALLEY...WITH A STRENGTHENING TEMPERATURE GRADIENT. A SURFACE FRONT IS EVENTUALLY FORECAST TO DEVELOP...AND MOVE VERY SLOWLY SOUTHEAST THROUGH THE CWA HEADING INTO MONDAY. TEMPERATURE FORECASTS ARE SOMEWHAT UNCERTAIN...GIVEN THE SHARP GRADIENT...BUT ABOVE-NORMAL TEMPERATURES ARE LIKELY SOUTH OF THE FRONT ON SUNDAY. A BRIEF PERIOD OF COOLER CONDITIONS CAN BE EXPECTED ON MONDAY...WITH OCCASIONAL SHOWERS AND A POSSIBLE MIX WITH SNOW ON MONDAY NIGHT. OVERALL MODEL AGREEMENT ON THE PRECIPITATION PATTERNS WITH THIS FRONT ARE FAIRLY STRONG...WITH A SLIGHT TREND TOWARD PRECIPITATION GETTING FURTHER SOUTH A LITTLE MORE QUICKLY ON MONDAY INTO MONDAY NIGHT. BY TUESDAY...STRONG SURFACE HIGH PRESSURE IS EXPECTED TO MOVE INTO THE NORTHEASTERN STATES...ALLOWING FOR A QUICK RETURN TO SOUTHERLY FLOW OVER MUCH OF THE EASTERN PART OF THE COUNTRY. THIS SHOULD ALLOW FOR ANOTHER PERIOD OF MILD (ABOVE NORMAL) TEMPERATURES ON TUESDAY AND ESPECIALLY ON WEDNESDAY. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... TAFS REMAIN WEDGED BETWEEN SYSTEMS THIS MORNING. MVFR CLOUDS TRAPPED UNDER HIGH PRESSURE RIDGE HAVE RETREATED BACK INTO NRN INDIANA AND NW OH...WHILE HIGH LEVEL CLOUDS ASSOCIATED WITH AN EAST COAST STORM STREAM ACROSS THE REGION. AS A H5 S/W DIGS OUT OF THE PLAINS IT WILL HELP THE FLOW TO PUSH THE MVFR CLOUDS SEWD OVERNIGHT. MODEL TIME SECTIONS ARE INDICATING THAT THEY COULD REACH KDAY AROUND SUNRISE. MODELS ONCE AGAIN ARE STALLING THE SE ADVANCEMENT OF THE MVFR CIGS AROUND I-71...MAKING THE CLOUD FORECAST TRICKY. BROUGHT THE MVFR CIGS INTO CVG/LUK FOR A COUPLE OF HOURS LATE THIS MORNING...THEN PULLED THEM BACK TO THE NW. WITH THE EAST COAST STORM HOLDING THINGS UP...CIGS ACROSS THE EASTERN TAFS WILL LOWER LATER THIS MORNING...BUT SHOULD REMAIN VFR. AS EAST COAST STORM PULLS AWAY LATER TODAY...THE WEAK CLIPPER SYSTEM DIVES INTO THE TN VALLEY...KEEPING CLOUDS ACROSS THE AREA. OUTLOOK...MVFR CEILINGS POSSIBLE WEDNESDAY NIGHT INTO THURSDAY NIGHT AND AGAIN SATURDAY. MVFR/IFR CEILINGS AND MVFR VISIBILITIES POSSIBLE SATURDAY NIGHT INTO SUNDAY. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...NONE. KY...NONE. IN...NONE. && $$ SYNOPSIS... NEAR TERM...HICKMAN SHORT TERM... LONG TERM...HATZOS AVIATION...SITES
AREA FORECAST DISCUSSION
NWS PORTLAND OR
909 PM PST TUE NOV 25 2014 .SYNOPSIS...A WARM FRONTAL BOUNDARY OVER WESTERN WASHINGTON WILL CONTINUE TO LIFT NORTH TONIGHT AND WEDNESDAY. HIGH PRESSURE ALOFT WEDNESDAY SHOULD BE STRONG ENOUGH TO KEEP MOST OF THE AREA DRY...EXCEPT FOR SW WASHINGTON. THE NEXT WEATHER SYSTEM REACHES THE COAST LATE WED EVENING AND THEN MOVES INLAND OVERNIGHT AND INTO THANKSGIVING MORNING. MUCH COOLER AIR ASSOCIATED WITH THE NORTHERN BRANCH OF THE JET STREAM IS FORECAST TO SPREAD OVER THE AREA THIS WEEKEND...FOR ANOTHER ROUND OF EAST WIND IN THE COLUMBIA RIVER GORGE. SNOW LEVELS WILL LOWER DRAMATICALLY THIS WEEKEND...BUT SLOWLY RISE EARLY NEXT WEEK. && .UPDATE...RADAR SHOWS LIGHT RAIN...MOSTLY OROGRAPHICALLY INDUCED...OVER THE COAST RANGE AND SOUTH WASHINGTON AND NORTH OREGON CASCADES...WITH RAIN RATES OF ONLY A FEW HUNDREDTHS OF AN INCH PER HOUR. AS RIDGING BUILDS INTO THE AREA FROM THE SOUTH...RAIN WILL TAPER OFF THROUGH WEDNESDAY. EXPECT THE WILLAMETTE VALLEY TO REMAIN DRY THROUGH THE OVERNIGHT HOURS AND INTO WEDNESDAY. WITH CLEARING SKIES PARTICULARLY IN THE SOUTH AND CENTRAL WILLAMETTE VALLEY...SHOULD SEE SOME FOG LATER TONIGHT AND WEDNESDAY MORNING BUT ANY VISIBILITY BELOW ABOUT 1/2 MILE SHOULD BE ISOLATED. FOR THE FORECAST UPDATE...TOOK OUT POPS FOR TONIGHT AND WEDNESDAY IN THE WILLAMETTE VALLEY AND TAPERED RAIN CHANCES ELSEWHERE OFF SLIGHTLY FASTER. ALSO RAISED HIGH TEMPERATURES WEDNESDAY A COUPLE OF DEGREES BASED ON TODAY`S OBSERVED HIGHS AND A PERSISTENT PATTERN. FINALLY...HAVE INCREASED WINDS ALONG THE COAST TOMORROW NIGHT BASED ON LATEST MODELS. EXPECT WINDY BUT SUB-WARNING CONDITIONS. BOWEN .SHORT TERM (PREVIOUS DISCUSSION)...TONIGHT THROUGH FRIDAY...500 MB RIDGE REMAINS CENTERED ALONG 130W WITH A BAROCLINIC ZONE RIDING OVER THE TOP. KLGX RADAR INDICATING RETURNS OVER MUCH OF SW WA. HOWEVER...ECHO INTENSITY HAS DIMINISHED AND THIS IS EVIDENT IN THE LATEST 6-HR PRECIP AMOUNTS. RAINFALL RATES AS OF 21Z IN THE SW WA CASCADES AND FOOTHILLS HAVE EASED TO AROUND ONE TENTH OR LESS. 24-HR TOTALS GENERALLY 1 TO 3 INCHES...WITH SOME SNOTELS COMING IN WITH 3.5 INCHES. 500 MB HEIGHTS NEAR 570 DM COMBINED WITH 1000-500 MB THICKNESS VALUES IN THE MID TO UPPER 550S AND 850 MB TEMPS 8-10C HAVE RESULTED IN NEAR-RECORD DAYTIME TEMPERATURES IN THE WILLAMETTE VALLEY. THE MILD AIR MASS WILL BE CONDUCING TO VALLEY FOG FORMATION TONIGHT...ESPECIALLY WITH THE RELATIVELY HIGH DEW POINTS. FOG WILL FAVOR THE SOUTH HALF OF THE AREA WHERE LESS CLOUD COVER IS EXPECTED. THE THANKSGIVING FRONT IS STILL ON TRACK TO REACH THE COASTLINE LATE WED EVENING THEN MIGRATE INLAND OVERNIGHT AND THANKSGIVING MORNING. THE REMNANTS OF THE FRONTAL BOUNDARY STALL ACROSS THE INTERIOR VALLEYS AND CASCADES THANKSGIVING NIGHT. THE GFS AND ECMWF HANDLE THE QPF FIELD VALID 06Z FRI QUITE DIFFERENTLY. THE GFS SHOWS AN OBVIOUS BREAK IN THE FRONTAL BOUNDARY...WITH SEPARATE QPF BULLS-EYES OVER FAR SW OREGON AND ALSO IN THE S WA CASCADES AND FOOTHILLS. THE ECMWF SHOW A MUCH LARGER SRN QPF AREA EXTENDING FURTHER N...TO THE CENTRAL INTERIOR VALLEYS AND CASCADES. BY 12Z FRI THE ECMWF HAS A BROAD SWATH OF QPF OVER THE ENTIRE FORECAST AREA WHILE THE GFS MAINTAINS THE TWO SEPARATE AND DISTANT CORES. IN ANY EVENT...THE AIR MASS WILL REMAIN QUITE MILD THROUGH THU NIGHT WITH SNOW LEVELS WELL ABOVE THE CASCADE PASSES. THINGS START TO CHANGE FRI AS BOTH THE ECMWF AND GFS SHOW THE NORTHERN AND SOUTHERN JET STREAM BRANCHES PHASING TOGETHER. BOTH MODELS HAVE A MUCH COLDER CANADIAN AIR MASS SAGGING S THROUGH NRN WA FRI. MODELS DEVELOP AN AREA OF ENHANCED QPF ALONG THE REMNANT FRONTAL BOUNDARY. THE EXACT LOCATION OF THIS BOUNDARY REMAINS IN QUESTION. THE GFS HAS IT ALONG A LINE FROM NEWPORT TO ALBANY WHILE THE ECMWF HAS IT A BIT MORE NORTH BUT WITH LESSER AMOUNTS. WEISHAAR .LONG TERM...FRIDAY NIGHT THROUGH TUESDAY...COMPLICATED PATTERN EVOLVES FRIDAY NIGHT AND SAT WITH THE COLDER AIR CONTINUING TO SLIDE S THROUGH WA AND INTO NRN OREGON. 12Z GFS MORE IN LINE WITH THE PREVIOUS COUPLE OF ECMWF RUNS...DEPICTING A COLD AIR WEDGE IN THE CENTRAL COLUMBIA GORGE BY 00Z SUN. LOOK FOR THE EAST WIND TO RETURN AS WELL...BEGINNING SAT MORNING AND CONTINUING THROUGH THE WEEKEND. BY 00Z SUN THE GFS HAS -8 TO -10C 850 MB AIR IN THE CENTRAL COLUMBIA GORGE...WHILE THE ECMWF IS JUST A TOUCH WARMER. FORTUNATELY...THE DRIER NLY FLOW WILL SHUNT PRECIP FURTHER TO THE S. A CLOSED LOW WELL OF THE NRN CA COAST SAT STARTS TO DRIFT NE SAT NIGHT AND SUN. THERE IS THE POTENTIAL FOR A DEFORMATION BAND OVER NRN CA TO DRIFT NWD LATE SUN INTO MON. THIS COULD BE PROBLEMATIC AS THE MOISTURE OVERRUNS THE COLD AIR....ESPECIALLY FOR THE COLUMBIA GORGE AND UPPER HOOD RIVER VALLEY. WEISHAAR && .AVIATION...CONDITIONS HAVE DRAMATICALLY IMPROVED OVER THE LAST COUPLE HOURS FOR THE INLAND LOCATIONS WHILE THE COAST HAS LARGELY REMAINED IFR OR WORSE THIS EVENING. MODELS HAVE NOT BEEN HANDLING THE SITUATION WELL AT ALL AS ABUNDANT LOW LEVEL MOISTURE HAS REMAINED. THE UPPER RIDGE WILL CONTINUE TO BUILD AS IT TRANSITS THE REGION WITH SURFACE WINDS ON DECREASING. DEW POINTS ARE IN THE 50S AT THIS HOUR BUT SHOULD LOWER SOME THIS EVENING. HAVE DOUBTS DEW POINTS WILL BE ABLE TO KEEP AHEAD OF TEMPERATURES AND EXPECT TO SEE FOG DEVELOP. CONFIDENCE IS FAR TOO LOW...HOWEVER...FOR SPECIFIC AREAS AND DECIDED AGAIN INCLUSION IN THE TAF PACKAGES ASIDE FROM KSLE AND KEUG. REGARDLESS...HAVE REASONABLE CONFIDENCE LOW STRATUS WILL DEVELOP INLAND WHERE FOG DOESN`T. DONT EXPECT MUCH IMPROVEMENT ABOVE IFR UNTIL PERHAPS AFTER 19-21Z. KPDX AND APPROACHES...VFR CIGS CURRENTLY BUT EXPECT LOW CLOUDS TO BREAK UP SOME WITH ENOUGH CLEARING ALLOWING FOR A LOWER STRATUS DECK TO DEVELOP OVERNIGHT. EXPECT A 015 TO 020 DECK WILL REMAIN UNTIL AROUND 20Z BEFORE CLEARING OUT THROUGH 27/06Z JBONK && .MARINE...WIND GUSTS ACROSS THE NORTHERN WATERS HAVE STAYED BELOW SMALL CRAFT CRITERIA WITH THE HRRR MODEL HAVING THE BEST HANDLE ON THE SITUATION AT THIS TIME. THAT MODEL DOES NOT BRING A THREAT FOR CRITERIA LEVEL GUSTS BACK UP UNTIL AFTER 5 AM EARLY WEDNESDAY. AS SUCH HAVE DROPPED THE SMALL CRAFT WIND ADVISORY FOR THE TIME BEING. SEAS ARE ALSO RUNNING ABOUT A FOOT BELOW GUIDANCE AND THE FORECAST SO HAVE ALSO LOWERED JUST A BIT. THE CURRENT SOUTHWEST WINDS WILL BACK TO THE SOUTH AND INCREASE AS A STRONG FRONT APPROACHES WEDNESDAY AFTERNOON. THIS FRONT WILL LIKELY PRODUCE GALE FORCE WINDS WEDNESDAY NIGHT WITH THE PREVIOUS SHIFT HAVING ISSUED A GALE WARNING. ANOTHER FRONT IS EXPECTED TO BRUSH BY THE SOUTHERN WATERS FRIDAY. THIS FRONT WILL APPROACH FROM THE SW AND THE MODELS VARY ON HOW FAR NORTH IT WILL REACH...AND ON THE TIMING. THEREFORE...THERE IS LOW CONFIDENCE FOR FRIDAY FORECAST. A LARGE LOW WILL DROP SOUTH FROM THE GULF OF ALASKA FRIDAY AND SETTLE SW OF THE WATERS THIS WEEKEND...AND GENERATE OFFSHORE WINDS THROUGH THE WEEKEND. THESE WINDS WILL LIKELY RESULT IN ENHANCED GUSTS NEAR THE COASTAL GAPS...POSSIBLY NEEDING A WIND HEADLINE. JBONK/TJ && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 4 AM TO 4 PM PST WEDNESDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO CASCADE HEAD OR OUT 60 NM. GALE WARNING FROM 4 PM WEDNESDAY TO 4 AM PST THURSDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 5 AM TO 9 AM PST WEDNESDAY. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 4 PM TO 10 PM PST WEDNESDAY. && $$ INTERACT WITH US VIA SOCIAL MEDIA WWW.FACEBOOK.COM/NWSPORTLAND WWW.TWITTER.COM/NWSPORTLAND THIS DISCUSSION IS FOR NORTHWEST OREGON AND SOUTHWEST WASHINGTON FROM THE CASCADE CREST TO 60 NAUTICAL MILES OFFSHORE. THE AREA IS COMMONLY REFERRED TO AS THE FORECAST AREA.
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
1149 PM EST TUE NOV 25 2014 .SYNOPSIS... HIGH PRESSURE WILL RETREAT TO THE NORTHEAST TONIGHT. LOW PRESSURE FORMING OFF THE SOUTHEAST COAST WILL DEEPEN SIGNIFICANTLY AS IT MOVES NORTHEASTWARD ALONG THE EAST COAST ON WEDNESDAY...BRINGING SIGNIFICANT SNOW TO MUCH OF CENTRAL PENNSYLVANIA. ANOTHER SHOT OF COLDER AIR WILL FOLLOW FOR THE END OF THE WEEK...BEFORE TEMPERATURES MODERATE OVER THE WEEKEND AND INTO EARLY NEXT WEEK. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... LITTLE CHANGE TO THE GOING FORECAST THIS EVENING. HIGH PRESSURE CENTERED ALONG THE IL/IN BORDER BUILDING EASTWARD THROUGH THE OHIO VALLEY WITH RIDGE AXIS EXTENDING NEWD ALONG THE LAKE ERIE SHORELINE TO LAKE ONTARIO. STRATUS IS PACKED AGAINST THE ALLEGHENIES OVER NORTHWEST PA. MID AND HIGH CLOUDS HAVE OVERTAKEN THE REMAINDER OF CENTRAL PA THIS EVENING...AND WILL BE THICKENING AS THE NIGHT WEARS ON. TEMPERATURES HAVE FALLEN TO THE LOWER 30S IN MOST PLACES AND WILL DROP A FEW MORE DEGREES ACROSS THE NORTH. STAGE IS SET FOR A LIGHT TO MODERATE SNOWFALL ACROSS A GOOD PART OF CENTRAL AND EAST CENTRAL PA. MINOR ADJUSTMENTS TO SNOWFALL MAP THIS EVENING FOR QUICKER EXIT OF SNOWFALL WEDNESDAY AFTERNOON... AND SLIGHTLY LESSER QPF ALONG THE WESTERN EDGE OF THE WARNINGS. HRW-ARW SUGGESTS ACCUMULATING SNOWFALL IS OVER BY 21Z...EVEN ACROSS THE EAST...AND IS THE MOST AGGRESSIVE IN PUSHING THE ACCUMULATING SNOWFALL OUT OF MY CWA WED AFTERNOON. HAVE NUDGED THINGS IN THAT DIRECTION...AS OTHER GUIDANCE IS ALSO FASTER...BUT MAINTAINED A BLEND OF GUIDANCE MID TO LATE AFTERNOON. FOR THE OVERNIGHT...PRECIP OVERSPREADING THE SOUTHERN TIER COUNTIES QUICKLY AFTER 08Z...WITH QPF APPROACHING A TENTH OF AN INCH BY 12Z. TEMPS ALOFT AND ON THE SURFACE SUGGEST THAT PRECIP STARTING OVER SOUTHERN /ESPECIALLY SE/ AREAS LATE TONIGHT WILL LIKELY BE AT LEAST A MIX OF RAIN AND SNOW WITH LIGHT SNOW ON THE NORTHERN EDGE. SIMPLY...PRECIP WILL MOVE INTO SOUTHERN HALF OF CWA BEFORE SUNRISE AND WILL BE LIGHT...BUT QUICKLY INTENSIFY DURING THE MORNING RUSH HOUR ACROSS THE SOUTH. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... WINTER STORM WARNINGS/ADVISORIES NOW IN EFFECT. A LOW PRESSURE SYSTEM DEVELOPS AND INTENSIFIES AS IT TRACKS FROM THE CAROLINA COAST AT 12Z WED TO OFF THE NJ COAST BY 00Z THU... BRINGING BIGGEST IMPACTS TO CENTRAL PA DURING THE DAY WED. CONFIDENCE IS GROWING IN THE STORM TRACK WITH GFS COMING IN LINE WITH THE ECMWF CLOSER TO THE COAST...WHICH WILL PUSH THE QPF SHIELD A BIT FURTHER WEST. PRECIP WILL BE ONGOING IN THE SOUTH BY SUNRISE...AND SPREADING QUICKLY INTO THE CENTRAL AND NORTHEAST BY MID MORNING. ANY RAIN WILL QUICKLY CHANGE TO SNOW IN THE SE AS COLUMN COOLS. PERIOD OF HEAVIEST INTENSITY PRECIP WILL BE WED MORNING THROUGH MID AFTERNOON...WHERE SNOW RATES COULD BE 1-2 INCHES PER HOUR IN THE WARNING AREA. LATEST WWD GRAPHICS CONTINUE TO SHOW A SWATH OF 6-8 SNOWS OVER THE SERN 1/3 OR SO OF MY FCST AREA. CONFIDENCE FOR SIG SNOWS UP INTO CENTRAL/NW PA NOT AS HIGH GIVEN THE LACK OF A SIG EASTERLY LOW LEVEL WIND ANOMALY IN THE ENSEMBLES...AND A SHORTWAVE SLIDING IN FROM THE WEST WHICH MAY SHARPEN GRADIENT OF SNOW. BUT FOR A COUPLE INCHES OF SNOW AND IMPACTS ON THE BUSIEST TRAVEL DAY OF THE YEAR WE STRUNG AN ADVISORY OVER THE NORTHERN EDGE OF THE WARNING AREA. SNOW SHOULD TAPER OFF QUICKLY BY LATE WED AFT/WED EVE AS STORM QUICKLY MOVES INTO NEW ENGLAND. FLOW TRANSITIONS BACK TO A NW FETCH ACROSS THE LAKES...WITH LIGHT SCT SNOW SHOWERS POSS BY THU MORNING IN THE UPSLOPE OF THE WESTERN HIGHER TERRAIN. && .LONG TERM /THURSDAY THROUGH TUESDAY/... UPPER TROFFING OVER THE EASTERN THIRD OF THE COUNTRY AT THE START OF THE LONG TERM PERIOD IS FORECAST TO FLATTEN OUT INTO AN EXTENSIVE WEST TO EAST ZONAL FLOW PATTERN COVERING MUCH OF NORTH AMERICA. HEIGHTS OVER THE NORTHEASTERN U.S. ARE THEN FORECAST TO RISE FROM LATE IN THE WEEKEND ONWARD AS THE CABOOSE IN THE CURRENT SHORTWAVE TRAIN EXITS THE EAST COAST ON FRIDAY AND ENERGY APPROACHING THE PACIFIC COAST CLOSES OFF AND BUILDS HEIGHTS OVER THE WESTERN AND CENTRAL U.S. A SHOT OF COLD AIR WILL MOVE INTO THE REGION FOR THURSDAY AND FRIDAY BEHIND THE AFOREMENTIONED CABOOSE SHORTWAVE. THIS WAVE MAY ALSO SUPPORT AN AREA OF PCPN MOVING WEST TO EAST ACROSS THE STATE THANKSGIVING DAY. ADDITIONALLY...THIS PUSH OF ENERGY/COLD AIR SHOULD GENERATE THE USUAL POST FRONTAL LAKE AND OROGRAPHICALLY ENHANCED SNOW SHOWERS IN THE WAKE OF THE DEPARTING STORM SYSTEM WITH WESTERN AND NORTHERN AREAS SEEING THE BEST CHANCE OF SCATTERED LIGHT SNOWS...WHILE THE REST OF THE REGION SEES LITTLE OR NO SNOW SHOWER ACTIVITY AT ALL. A BROAD WSW FLOW ALOFT ASSOCIATED WITH THE RISING HEIGHTS WILL MAKE THIS COLD SHOT TEMPORARY WITH WARMER AIR BEGINNING TO MAKE A RETURN BY SATURDAY. HIGHS WILL RETURN TO NEAR OR EVEN A TICK ABOVE NORMAL BY THE WEEKEND BEFORE COOLER AIR APPROACHES AGAIN FOR EARLY NEXT WEEK. A FRONTAL SYSTEM IN ADVANCE OF THE WARM AIR WILL MOVE ACROSS THE STATE ON SUNDAY...BRINGING THE BEST CHANCE OF PCPN DURING THE PERIOD. && .AVIATION /06Z WEDNESDAY THROUGH SUNDAY/... 26/03Z UPDATE...MINOR CHANGES TO ONSET OF PCPN. PROJECTED ONSET MAY BE A BIT FAST WITH THE LATEST HRRR FAVORING THE 12-15Z WINDOW ACROSS THE SRN AIRFIELDS. MDL SOUNDINGS AND HIGH RES GUIDANCE STILL SHOW RELATIVELY QUICK CHANGEOVER FROM RAIN-TO-SNOW OVER THE SE TERMINALS WITH ALL SNOW PTYPES EXPANDING NWD TO FIG-IPT LINE BY 15Z. FINALLY...BFD REMAINS ON EDGE OF LOW CLOUDS AND MVFR CIGS ACROSS NE OH/NW PA INTO WRN NY. 26/00Z...LOW PRESSURE DEVELOPING OFF THE SOUTHEAST COAST LATE TONIGHT WILL STRENGTHEN AS IT LIFTS NWD JUST OFF THE EAST COAST THROUGH WED NGT. EXPECT RAPIDLY DETERIORATING CONDS FROM SOUTH TO NORTH DURING THE PREDAWN AND EARLY MORNING HOURS AS SNOW OVERSPREADS THE AIRSPACE. PCPN WILL LKLY BEGIN AS A MIX IN THE MDT/LNS AREA BEFORE CHANGING TO ALL SNOW. MOST INTENSE SNOWFALL RATES AND REDUCED VSBYS WILL BE OVER THE SERN AIRSPACE WITH RATES UP TO 2"/HR WITH FLGT CATS AOB AIRFIELD MINS. HIGH CONFIDENCE IN WIDESPREAD IFR CONDS DUSK-DAWN BEFORE SNOW ENDS FROM SW TO NE BY WED NGT. LOW CIGS SHOULD PERSIST OVER THE WRN 1/3 OF THE AREA WED NGT WITH MARGINAL IMPROVEMENT ELSEWHERE. OUTLOOK... THU...IFR/MVFR WITH OCNL -SHSN WRN 1/3. VFR TO MVFR CIGS CNTRL/EAST. FRI...AM MVFR/-SHSN NW...OTHERWISE BCMG VFR. SAT-SUN...MAINLY VFR. -SHRA PSBL. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING FROM 3 AM WEDNESDAY TO 4 AM EST THURSDAY FOR PAZ019-042-045-046-049>053. WINTER WEATHER ADVISORY FROM 3 AM WEDNESDAY TO 4 AM EST THURSDAY FOR PAZ012-017-018-037-041. WINTER STORM WARNING FROM 3 AM WEDNESDAY TO MIDNIGHT EST WEDNESDAY NIGHT FOR PAZ024>028-033>036-056>059-063>066. && $$ SYNOPSIS...RXR/STEINBUGL NEAR TERM...DEVOIR/RXR SHORT TERM...RXR LONG TERM...LA CORTE/GARTNER AVIATION...STEINBUGL
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
1134 PM MST TUE NOV 25 2014 .UPDATE... ISSUED AT 1129 PM MST TUE NOV 25 2014 WINDS ARE DECREASING ACROSS FAR NWRN SD SO HAVE CANCELLED THE WIND ADVISORY FOR THAT AREA. WILL KEEP THE ADVISORY GOING FOR WCNTRL SD FOR THE TIME BEING BUT THAT MAY END UP BEING CANCELLED EARLY AS WELL. UPDATE ISSUED AT 916 PM MST TUE NOV 25 2014 SNOW IS DECREASING FROM NORTH TO SOUTH AS PRES RISES MOVE IN FROM THE NORTH BEHIND CDFNT. THE MDT/HEAVY BAND OF SNOW OVER THE BLKHLS IS DIMINISHING WITH LITTLE ADDITIONAL ACCUMS EXPECTED THE REST OF THE NIGHT. WINDS SHOULD REMAIN QUITE GUSTY MUCH OF THE NIGHT AND WILL CONTINUE THE WIND ADVISORY. && .SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT ISSUED AT 205 PM MST TUE NOV 25 2014 THE LATEST WATER VAPOR IMAGES AND RAP ANALYSES INDICATED A LARGE TROUGH OVER THE CNTRL/ERN CONUS WITH A RIDGE OVER THE WEST COAST. A POTENT SHORT-WAVE TROUGH WAS MOVING ACROSS ERN MT INTO NWRN SD...AIDED BY A 150-KT UPPER JET. SCT RAIN/SNOW SHOWERS WERE ACROSS MUCH OF WRN SD AND NERN WY...BUT WITH A DOWNSLOPE HOLE OVER PARTS OF SWRN SD. AREA WEBCAMS SHOWED AROUND ONE INCH OF SNOW OVER NERN WY...A TRACE OVER NWRN SD...AND 1-2 INCHES IN THE NRN BLKHLS. A SFC LOW OVER WRN ND WAS ASSOCIATED WITH 2-5MB/3HR PRES RISES AS IT MOVED SOUTHEAST...WITH NORTHWEST WINDS OF 20-35 MPH BEHIND THE LOW MOVING INTO NWRN SD. THERE IS DECENT MODEL AGREEMENT IN THE SHORT TERM THROUGH AT LEAST 12Z THU. HEIGHTS WILL BE RISING THROUGH THE PERIOD WITH THICKNESSES RISING WED THROUGH THU. FOR TNGT...THE SHORT-WAVE TROUGH MOVES TO NERN KS AS THE SFC LOW MOVES TO SWRN IA. THIS WILL TAKE MOST OF THE PRECIP SOUTHEAST OF THE AREA THIS EVNG...BUT NORTHWEST WINDS WILL INCREASE ACROSS MOST OF NWRN INTO SCNTRL SD. THE PREVIOUS WIND ADVY LOOKS GOOD AND WILL NOT CHANGE. BLSN IS EXPECTED TO BE MINIMAL GIVEN THE WARM TEMPS AND LIMITED SNOWFALL. A LOW-LEVEL BAROCLINIC ZONE WILL SETUP OVER THE WRN CWA SO WILL KEEP A CHANCE OF SNOW GOING THERE. COLDER AIR ALSO WILL FLOW INTO THE CWA TNGT GIVEN STRONG COLD ADVECTION. ON WED THE BAROCLINIC ZONE INTENSIFIES ACROSS THE WRN CWA...WITH WARM ADVECTION AND FRONTOGENESIS AIDING IN MESOSCALE LIFT ON THE ANTICYCLONIC SIDE OF THE UPPER JET. DESPITE WEAK UPPER FORCING...THE LOW-LEVEL FORCING AND NEARLY SATURATED PROFILES SHOULD LEAD TO SNOW OVER NERN WY INTO WRN SD. THIS WILL SPREAD NEWD WED NGT AS UPPER HEIGHTS CONTINUE TO BUILD AND LOW-LEVEL WARM ADVECTION INTENSIFIES. SREF PTYPE PROBABILITIES AND NAM VERTICAL PROFILES SUPPORT A CHANCE OF FZRA OVER PARTS OF NWRN SD LATE WED NGT INTO THU MRNG...SO HAVE ADDED THAT TO THE FCST. && .LONG TERM...THURSDAY THROUGH TUESDAY ISSUED AT 205 PM MST TUE NOV 25 2014 SNOW/FREEZING RAIN WILL GRADUALLY EXIT THE AREA ON THANKSGIVING... LINGERING THE LONGEST OVER NW SD. THE TRICKIEST PART OF THE LONG TERM FORECAST WILL BE TEMPS... PARTICULARLY THURSDAY AND SATURDAY. LOW AMPLITUDE RIDGING WILL DEVELOP THANKSGIVING DAY ACROSS THE ROCKIES INTO THE NORTHERN PLAINS. STRONG WARM AIR ADVECTION WILL DEVELOP WEDNESDAY NIGHT INTO THURSDAY PUSHING THE WARM FRONT NE INTO THE CENTRAL DAKOTAS. THE RESULT WILL BE DRY AND MUCH WARMER WEATHER FOR THANKSGIVING AND FRIDAY. JUST HOW WARM THE SD PLAINS WILL GET ON THURSDAY DEPENDS ON THE MOVEMENT OF THE WARM FRONT...AS MODELS HAVE A 10-15 DEGREE SPREAD ACROSS THAT AREA. CURRENTLY HAVE HIGHS RANGING FROM THE 30S ACROSS NW SD TO THE MID 50S IN PORTIONS OF NE WY AND SW SD. ON FRIDAY...HIGHS WILL REACH THE UPPER 40S TO MID 50S. THE NEXT COLD FRONT WILL PASS THROUGH THE AREA SATURDAY AS A SHALLOW TROUGH CROSSES SRN CANADA INTO MT/ND. AGAIN HIGHS WILL DEPEND ON THE POSITIONING OF THE FRONT...BUT WILL MOST LIKELY BE REACHED IN THE MORNING...AS TEMPS WILL BE DROPPING THROUGH THE DAY INTO THE TEENS AND 20S...AND THEN SINGLE DIGITS OVERNIGHT. GFS AND ECMWF ENSEMBLES HAVE A 45-50 DEGREE SPREAD FOR THE HIGHS ON SATURDAY...AND ABOUT A 30 DEGREE SPREAD FOR LOWS...SO THERE IS MUCH UNCERTAINTY WITH THE TEMPERATURE FORECAST. SOME LIGHT SNOW CAN BE EXPECTED TO MOVE SOUTHWARD BEHIND THE COLD FRONT SATURDAY INTO SATURDAY NIGHT. WELL BELOW AVERAGE TEMPS ARE EXPECTED SUNDAY...WITH SOME LINGERING LIGHT SNOW POSSIBLE. THEN MODELS SHOW WARMER AIR ADVECTING BACK IN EARLY NEXT WEEK POTENTIALLY RESULTING IN NEAR AVERAGE TEMPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 916 PM MST TUE NOV 25 2014 WINDS WILL GUST OVER 40KTS AT TIMES TONIGHT...ESPECIALLY OVER NWRN SD. -SN WILL CONTINUE AT TIMES TONIGHT INTO WED...ESPECIALLY OVER NERN WY AND FAR WRN SD. MVFR/IFR CIGS WILL CONTINUE TO SPREAD SWD ACRS THE REGION TONIGHT BEHIND THE CDFNT...AND CONTINUE THROUGH THE DAY ON WED...WITH SOME LIFR CONDITIONS POSSIBLE ACRS NERN WY INTO THE NRN BLKHLS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL 5 AM MST WEDNESDAY FOR SDZ014-026-031-032- 043-072-073. WY...NONE. && $$ UPDATE...JOHNSON SHORT TERM...BUNKERS LONG TERM...POJORLIE AVIATION...JOHNSON
AREA FORECAST DISCUSSION FOR WESTERN SD AND NORTHEASTERN WY
NWS RAPID CITY SD
921 PM MST TUE NOV 25 2014 .UPDATE... ISSUED AT 916 PM MST TUE NOV 25 2014 SNOW IS DECREASING FROM NORTH TO SOUTH AS PRES RISES MOVE IN FROM THE NORTH BEHIND CDFNT. THE MDT/HEAVY BAND OF SNOW OVER THE BLKHLS IS DIMINISHING WITH LITTLE ADDITIONAL ACCUMS EXPECTED THE REST OF THE NIGHT. WINDS SHOULD REMAIN QUITE GUSTY MUCH OF THE NIGHT AND WILL CONTINUE THE WIND ADVISORY. && .SHORT TERM...THIS EVENING THROUGH WEDNESDAY NIGHT ISSUED AT 205 PM MST TUE NOV 25 2014 THE LATEST WATER VAPOR IMAGES AND RAP ANALYSES INDICATED A LARGE TROUGH OVER THE CNTRL/ERN CONUS WITH A RIDGE OVER THE WEST COAST. A POTENT SHORT-WAVE TROUGH WAS MOVING ACROSS ERN MT INTO NWRN SD...AIDED BY A 150-KT UPPER JET. SCT RAIN/SNOW SHOWERS WERE ACROSS MUCH OF WRN SD AND NERN WY...BUT WITH A DOWNSLOPE HOLE OVER PARTS OF SWRN SD. AREA WEBCAMS SHOWED AROUND ONE INCH OF SNOW OVER NERN WY...A TRACE OVER NWRN SD...AND 1-2 INCHES IN THE NRN BLKHLS. A SFC LOW OVER WRN ND WAS ASSOCIATED WITH 2-5MB/3HR PRES RISES AS IT MOVED SOUTHEAST...WITH NORTHWEST WINDS OF 20-35 MPH BEHIND THE LOW MOVING INTO NWRN SD. THERE IS DECENT MODEL AGREEMENT IN THE SHORT TERM THROUGH AT LEAST 12Z THU. HEIGHTS WILL BE RISING THROUGH THE PERIOD WITH THICKNESSES RISING WED THROUGH THU. FOR TNGT...THE SHORT-WAVE TROUGH MOVES TO NERN KS AS THE SFC LOW MOVES TO SWRN IA. THIS WILL TAKE MOST OF THE PRECIP SOUTHEAST OF THE AREA THIS EVNG...BUT NORTHWEST WINDS WILL INCREASE ACROSS MOST OF NWRN INTO SCNTRL SD. THE PREVIOUS WIND ADVY LOOKS GOOD AND WILL NOT CHANGE. BLSN IS EXPECTED TO BE MINIMAL GIVEN THE WARM TEMPS AND LIMITED SNOWFALL. A LOW-LEVEL BAROCLINIC ZONE WILL SETUP OVER THE WRN CWA SO WILL KEEP A CHANCE OF SNOW GOING THERE. COLDER AIR ALSO WILL FLOW INTO THE CWA TNGT GIVEN STRONG COLD ADVECTION. ON WED THE BAROCLINIC ZONE INTENSIFIES ACROSS THE WRN CWA...WITH WARM ADVECTION AND FRONTOGENESIS AIDING IN MESOSCALE LIFT ON THE ANTICYCLONIC SIDE OF THE UPPER JET. DESPITE WEAK UPPER FORCING...THE LOW-LEVEL FORCING AND NEARLY SATURATED PROFILES SHOULD LEAD TO SNOW OVER NERN WY INTO WRN SD. THIS WILL SPREAD NEWD WED NGT AS UPPER HEIGHTS CONTINUE TO BUILD AND LOW-LEVEL WARM ADVECTION INTENSIFIES. SREF PTYPE PROBABILITIES AND NAM VERTICAL PROFILES SUPPORT A CHANCE OF FZRA OVER PARTS OF NWRN SD LATE WED NGT INTO THU MRNG...SO HAVE ADDED THAT TO THE FCST. && .LONG TERM...THURSDAY THROUGH TUESDAY ISSUED AT 205 PM MST TUE NOV 25 2014 SNOW/FREEZING RAIN WILL GRADUALLY EXIT THE AREA ON THANKSGIVING... LINGERING THE LONGEST OVER NW SD. THE TRICKIEST PART OF THE LONG TERM FORECAST WILL BE TEMPS... PARTICULARLY THURSDAY AND SATURDAY. LOW AMPLITUDE RIDGING WILL DEVELOP THANKSGIVING DAY ACROSS THE ROCKIES INTO THE NORTHERN PLAINS. STRONG WARM AIR ADVECTION WILL DEVELOP WEDNESDAY NIGHT INTO THURSDAY PUSHING THE WARM FRONT NE INTO THE CENTRAL DAKOTAS. THE RESULT WILL BE DRY AND MUCH WARMER WEATHER FOR THANKSGIVING AND FRIDAY. JUST HOW WARM THE SD PLAINS WILL GET ON THURSDAY DEPENDS ON THE MOVEMENT OF THE WARM FRONT...AS MODELS HAVE A 10-15 DEGREE SPREAD ACROSS THAT AREA. CURRENTLY HAVE HIGHS RANGING FROM THE 30S ACROSS NW SD TO THE MID 50S IN PORTIONS OF NE WY AND SW SD. ON FRIDAY...HIGHS WILL REACH THE UPPER 40S TO MID 50S. THE NEXT COLD FRONT WILL PASS THROUGH THE AREA SATURDAY AS A SHALLOW TROUGH CROSSES SRN CANADA INTO MT/ND. AGAIN HIGHS WILL DEPEND ON THE POSITIONING OF THE FRONT...BUT WILL MOST LIKELY BE REACHED IN THE MORNING...AS TEMPS WILL BE DROPPING THROUGH THE DAY INTO THE TEENS AND 20S...AND THEN SINGLE DIGITS OVERNIGHT. GFS AND ECMWF ENSEMBLES HAVE A 45-50 DEGREE SPREAD FOR THE HIGHS ON SATURDAY...AND ABOUT A 30 DEGREE SPREAD FOR LOWS...SO THERE IS MUCH UNCERTAINTY WITH THE TEMPERATURE FORECAST. SOME LIGHT SNOW CAN BE EXPECTED TO MOVE SOUTHWARD BEHIND THE COLD FRONT SATURDAY INTO SATURDAY NIGHT. WELL BELOW AVERAGE TEMPS ARE EXPECTED SUNDAY...WITH SOME LINGERING LIGHT SNOW POSSIBLE. THEN MODELS SHOW WARMER AIR ADVECTING BACK IN EARLY NEXT WEEK POTENTIALLY RESULTING IN NEAR AVERAGE TEMPS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 916 PM MST TUE NOV 25 2014 WINDS WILL GUST OVER 40KTS AT TIMES TONIGHT...ESPECIALLY OVER NWRN SD. -SN WILL CONTINUE AT TIMES TONIGHT INTO WED...ESPECIALLY OVER NERN WY AND FAR WRN SD. MVFR/IFR CIGS WILL CONTINUE TO SPREAD SWD ACRS THE REGION TONIGHT BEHIND THE CDFNT...AND CONTINUE THROUGH THE DAY ON WED...WITH SOME LIFR CONDITIONS POSSIBLE ACRS NERN WY INTO THE NRN BLKHLS. && .UNR WATCHES/WARNINGS/ADVISORIES... SD...WIND ADVISORY UNTIL 5 AM MST WEDNESDAY FOR SDZ014-025-026-031- 032-043-072-073. WIND ADVISORY UNTIL 1 AM MST WEDNESDAY FOR SDZ001-002-012-013. WY...NONE. && $$ UPDATE...JOHNSON SHORT TERM...BUNKERS LONG TERM...POJORLIE AVIATION...JOHNSON
AREA FORECAST DISCUSSION
NWS AUSTIN/SAN ANTONIO TX
1234 PM CST WED NOV 26 2014 .UPDATE... HOURLY OBS CONTINUE TO SHOW STEEPER WARMING TREND THAN FORECAST AND WITH 70S ALREADY BEING OBSERVED ALONG I35 CORRIDOR...WENT AHEAD AND RAISED THE MAX T GRID. RUC MODEL SEEMED TO DECENTLY DEPICT MID 70S ACROSS THE AREA THIS AFTERNOON SO WENT WITH THAT FOR THE MOST PART. CONTINUING TO CLOSELY MONITOR WINDS ON THE EDWARDS PLATEAU AS DEWS IN THE TEENS ARE BEING SEEN THERE RESULTING IN VERY LOW RH VALUES. TB3 && .PREV DISCUSSION... /ISSUED 1137 AM CST WED NOV 26 2014/ UPDATE... PLEASE SEE 18Z AVIATION DISCUSSION BELOW. AVIATION... VFR SKC CONDITIONS PREVAIL ACROSS THE REGION CURRENTLY AND EXPECTED TO CONTINUE THROUGH THE PERIOD. SUSTAINED SURFACE WINDS WILL BE W/SW NEAR 10-15 KT WITH HIGHER GUSTS POSSIBLE TOWARDS 20 KT FOR KAUS WITH KSAT/KSSF SLIGHTLY LESS THROUGH EARLY AFTERNOON. WINDS WILL DECREASE BY THE LATE AFTERNOON BUT PIVOT TO THE NORTH THROUGH THE EVENING AS A WEAK COOL FRONT MOVES THROUGH. /ALLEN/ PREV DISCUSSION... /ISSUED 1017 AM CST WED NOV 26 2014/ UPDATE... AT 16Z...SKIES WERE CLEAR WITH WINDS GENERALLY OUT OF THE WEST FROM 5-15MPH. WILL CONTINUE TO KEEP AN EYE ON THE NORTHERN RIO GRANDE VALLEY AS RH VALUES SHOULD DROP INTO THE TEENS OUT THERE. HOURLY T GRIDS WERE A BIT SLOW TO WARM THIS MORNING SO MADE SOME ADJUSTMENTS TO COMPENSATE. MAY NEED TO RAISE MAX T A COUPLE DEGREES IF THAT TREND CONTINUES. OTHERWISE...FORECAST IS ON TRACK. PREV DISCUSSION... /ISSUED 347 AM CST WED NOV 26 2014/ SHORT TERM (TODAY THROUGH THURSDAY)... AN UPPER LEVEL TROUGH MOVING EAST THROUGH THE EASTERN PLAINS TO THE LOWER OHIO VALLEY WILL SEND A COLD FRONT SOUTH INTO SOUTH CENTRAL TEXAS LATE THIS AFTERNOON INTO TONIGHT. AHEAD OF THE FRONT...SOUTHWESTERLY WINDS WILL CONTINUE THE WARMING TREND WITH TEMPERATURES SLIGHTLY ABOVE AVERAGE TODAY. IN THE WAKE OF THE FRONT...COOLER...AND SLIGHTLY BELOW AVERAGE TEMPERATURES ARE EXPECTED ON THANKSGIVING DAY. LONG TERM (THURSDAY NIGHT THROUGH TUESDAY)... THE SURFACE HIGH MOVES OFF TO THE EAST THURSDAY NIGHT INTO FRIDAY. SOUTHERLY FLOW RETURNS WITH INCREASING LOWER LEVEL MOISTURE AND A WARMING TREND FOR THE REMAINDER OF THE THANKSGIVING WEEKEND. A DRY ZONAL FLOW FLOW ALOFT WILL PREVAIL. SOME LOW CLOUDS RETURN FRIDAY MORNING WITH A BETTER CHANCE SATURDAY MORNING. A WEAK UPPER LEVEL TROUGH MOVING ACROSS SOUTHERN TEXAS AND THE LOW LEVEL JET MAY LIFT A SOMEWHAT DEEPER LOWER LEVEL MOIST LAYER TO GENERATE ISOLATED SHOWERS ACROSS FAR EASTERN AREAS SUNDAY INTO SUNDAY NIGHT. MODELS THEN DIFFER IN THE LOWER LEVELS FOR MONDAY INTO TUESDAY WHILE ALL KEEP A ZONAL FLOW ALOFT. A COUPLE OF UPPER LEVEL TROUGHS MOVING EAST ACROSS THE NORTHERN TIER OF STATES AND SOUTHERN CANADA FORCE A RATHER STRONG COLD FRONT SOUTH ACROSS THE PLAINS. THE ECMWF AND GEM SHOW A STRONGER COLD FRONTAL PUSH ACROSS SOUTH CENTRAL TEXAS ON MONDAY WHILE THE GFS HAS A WEAKER FRONTAL PUSH AND THE NAVGEM KEEPS THE FRONT NORTH. THE GFS HAS BEEN MORE CONSISTENT AND WILL FAVOR THAT MODEL...ESPECIALLY WITH A ZONAL FLOW ALOFT SLOWING THE SOUTHWARD PROGRESS OF THE FRONT AND ERODING THE COLD AIRMASS ON ITS SOUTHERN END. THE FRONT STALLS OVER SOUTHERN TEXAS MONDAY NIGHT AND THEN MOVES BACK NORTH TUESDAY. THE LOW LEVEL JET AND THE FRONT MAY GENERATE ISOLATED SHOWERS ACROSS EASTERN AREAS MONDAY. ISENTROPIC LIFT OVER THE FRONT MAY GENERATE ISOLATED SHOWERS ACROSS EASTERN INTO CENTRAL AREAS TUESDAY. TOTAL RAINFALL AMOUNTS WILL BE LIGHT...GENERALLY LESS THAN 1/10 INCH FOR SUNDAY THROUGH TUESDAY. COOLER TEMPERATURES ARE EXPECTED BY TUESDAY. && .PRELIMINARY POINT TEMPS/POPS... AUSTIN CAMP MABRY 41 65 44 71 55 / 0 0 0 - - AUSTIN BERGSTROM INTL AIRPORT 37 64 41 72 53 / 0 0 0 - - NEW BRAUNFELS MUNI AIRPORT 40 66 44 71 53 / 0 0 0 0 - BURNET MUNI AIRPORT 38 62 42 69 49 / 0 0 0 0 - DEL RIO INTL AIRPORT 39 66 44 70 46 / 0 0 0 0 0 GEORGETOWN MUNI AIRPORT 37 63 43 70 54 / 0 0 0 - - HONDO MUNI AIRPORT 37 66 42 72 48 / 0 0 0 0 - SAN MARCOS MUNI AIRPORT 39 65 43 71 53 / 0 0 0 0 - LA GRANGE - FAYETTE REGIONAL 41 65 45 71 56 / 0 0 0 - - SAN ANTONIO INTL AIRPORT 42 66 47 72 54 / 0 0 0 0 - STINSON MUNI AIRPORT 42 67 46 73 53 / 0 0 0 0 - && .EWX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ MESOSCALE/AVIATION...15 SYNOPTIC/GRIDS...03 PUBLIC SERVICE/DATA COLLECTION...32
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
542 PM CST THU NOV 27 2014 .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 339 PM CST THU NOV 27 2014 AT 3 PM...A 1033 MB SURFACE HIGH...CENTERED OVER SOUTHEAST MINNESOTA AND NORTHEAST IOWA...WAS PRODUCING PARTLY TO MOSTLY SUNNY SKIES ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. DESPITE... THE SUNSHINE...TEMPERATURES WERE VERY COLD RANGING FROM 3 IN AUSTIN MINNESOTA TO 21 IN LONE ROCK WISCONSIN. FOR TONIGHT AND FRIDAY...27.12Z MODELS ARE IN GOOD AGREEMENT THAT A SHORT WAVE OVER WESTERN NORTH DAKOTA WILL MOVE QUICKLY SOUTHEAST ACROSS NORTHERN MINNESOTA TONIGHT...AND NORTHERN WISCONSIN ON FRIDAY. AS THIS SYSTEM APPROACHES...A BAND OF MODERATE TO STRONG 900 TO 600 MB FRONTOGENESIS WILL MOVE EAST ACROSS THE UPPER MISSISSIPPI RIVER VALLEY. THIS BAND WILL MOVE EAST THROUGH SOUTHEAST MINNESOTA AND NORTHEAST IOWA BETWEEN 28.06Z TO 28.10Z...AND THROUGH WESTERN WISCONSIN BETWEEN 28.09Z AND 28.18Z. THERE IS PLENTY OF DRY AIR AHEAD OF THIS WAVE...SO THE INITIAL LIFT WILL GO TO SATURATING THE AIR MASS BELOW 700 MB. ONCE SATURATED THE SOUNDINGS INITIALLY SHOW THAT THE 850 MB TO 550 MB LAYER WILL BE LOCATED IN THE DENDRITIC GROWTH ZONE NORTH OF INTERSTATE 94...AND ONLY ABOUT 50 TO 100 MB SOUTH OF THIS INTERSTATE. HOWEVER AS STRONG WARM AIR ADVECTION CONTINUES THROUGH THE NIGHT...THE AMOUNT OF AREA IN THE DENDRITIC GROWTH ZONE BECOME LESS AND LESS...WENT WITH THE HIGHEST SNOW TO LIQUID RATIOS THIS INITIALLY...AND THEN DECREASE THEM ON FRIDAY. SNOW TOTALS WILL THE GREATEST NORTH OF WISCONSIN 29 /FAR NORTHERN CLARK AND TAYLOR COUNTIES IN NORTH CENTRAL WISCONSIN/ WHERE SNOW TOTALS ARE AROUND 3 INCHES. DUE TO THIS SNOW...ISSUED A WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT THROUGH 3 PM FRIDAY. FURTHER SOUTH...EXPECT SNOW TOTALS OF 1 TO 3 INCHES BETWEEN INTERSTATE 94 AND WISCONSIN 29...AND FROM A TRACE TO AN INCH /NEAR INTERSTATE 90/ FOR THE REMINDER OF THE AREA. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 339 PM CST THU NOV 27 2014 ON SATURDAY...VERY WARM AIR WILL BE BROUGHT ISENTROPICALLY OFF OF THE CENTRAL PLAINS. UNFORTUNATELY THIS AIR WILL NOT MIX DOWN TO THE SURFACE. AS A RESULT...ONLY HAVE HIGH TEMPERATURES RANGING FROM THE MID 30S TO MID 40S. ONLY THING WE WILL HAVE TO WATCH IS THAT THE MODELS MAY BE UNDOING SOME OF WARMING AS THEY TRY TO MELT THE SNOW ON THE GROUND. LIKE YESTERDAY...THE NAM IS INITIALLY RUNNING ABOUT 1 TO 2 INCHES TOO HIGH ON THEIR SNOW DEPTH. WE WILL HAVE TO WATCH THIS PERIOD CLOSELY. ARCTIC COLD FRONTS WILL MOVE QUICKLY SOUTHEAST ACROSS THE AREA ON SUNDAY MORNING AND LATE SUNDAY NIGHT. THE 850 MB TEMPERATURES BEHIND THE FIRST FRONT WILL FALL FROM A BALMY 8-14C AT 12Z SUNDAY TO 0 TO -12C BY 00Z MONDAY...AND EVEN COLDER AIR MASS /-16 TO -22C/ WILL MOVE INTO THE AREA BY 12Z MONDAY. HIGH TEMPERATURES CURRENTLY RANGE FROM 8 TO 20F ON MONDAY. HOWEVER THE ECMWF SUGGEST THAT THE TEMPERATURES WILL BE VERY SIMILAR TO WHAT THEY WERE THIS AFTERNOON. FROM WEDNESDAY NIGHT THROUGH THURSDAY...THE GFS AND ECMWF CONTINUE TO DISAGREE ON WHETHER A LOW PRESSURE SYSTEM WILL AFFECT THE AREA OR NOT. THE GFS KEEPS PERIODICALLY MOVING A LOW INTO THE AREA. SOMETIMES IT IS LOCATED OF THE MID MISSISSIPPI RIVER VALLEY AND OTHER TIMES TO THE NORTHWEST AND WEST OF THE AREA. MEANWHILE THE ECMWF HAS KEPT HIGH PRESSURE ACROSS THE AREA. DUE TO THIS...MADE A CHANGE TO THE MODEL CONSENSUS AND REMOVED THE 20 TO 30 PERCENT PRECIPITATION CHANCES. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z FRIDAY EVENING) ISSUED AT 542 PM CST THU NOV 27 2014 THE MAIN CONCERN IS WHETHER THE INCOMING LIGHT SNOW WILL AFFECT THE TAF SITES OR STAY TO THE NORTH. LOOKING AT THE 27.18Z NAM AND GFS ALONG WITH THE 27.21Z RAP...THERE APPEARS TO HAVE BEEN A SOUTHWESTWARD SHIFT WITH THE MAIN AXIS OF FRONTOGENESIS. AROUND 28.09Z...THIS IS EXPECTED TO EXTEND FROM NORTHWEST MINNESOTA INTO WESTERN WISCONSIN WITH THE BAND OF LIGHT SNOW ON THE SOUTHWEST SIDE OF THIS FRONTOGENESIS. THIS WOULD BRING THE BAND ACROSS BOTH TAF SITES DURING THE OVERNIGHT HOURS. THE 21.15Z SREF WAS ALSO HINTING AT THIS WITH HIGH PROBABILITIES OF SUB 3 MILE VISIBILITIES FOR BOTH SITES. WILL SHOW THE SNOW MOVING IN OVERNIGHT WITH MVFR CONDITIONS BUT NOT LASTING MORE THAN ABOUT 4 HOURS AS THE FRONTOGENESIS WILL QUICKLY MOVE EAST ALLOWING THE BAND OF SNOW TO QUICKLY MOVE EAST AS WELL. BOTH THE NAM AND RAP INDICATE LOTS OF LOW LEVEL MOISTURE WILL REMAIN TRAPPED BELOW THE INVERSION AND HAVE OPTED TO MAINTAIN MVFR CEILINGS THROUGH THE DAY FRIDAY BASED ON THIS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY FROM MIDNIGHT TONIGHT TO 3 PM CST FRIDAY FOR WIZ017. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...04
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
352 PM CST WED NOV 26 2014 .SHORT TERM...(THIS EVENING THROUGH THURSDAY) ISSUED AT 351 PM CST WED NOV 26 2014 AT 3 PM...A SURFACE LOW WAS LOCATED OVER NORTHEAST MISSOURI. AN INVERTED TROUGH EXTENDS NORTH NORTHWEST OF THIS LOW THROUGH CENTRAL IOWA INTO SOUTH CENTRAL MINNESOTA. FURTHER NORTHWEST AN ARCTIC COLD FRONT EXTENDED FROM THE WESTERN TIP OF LAKE SUPERIOR SOUTHEAST TO SIOUX FALLS SOUTH DAKOTA. TEMPERATURES AHEAD OF THIS COLD FRONT WERE IN THE MID AND UPPER 20S. MEANWHILE IN THE WAKE OF THIS FRONT...TEMPERATURES RANGED FROM 0 TO THE LOWER 20S. THE COMBINATION OF LIFT ASSOCIATED WITH THE TROUGH AND THE COLD FRONT PRODUCED SNOW ACROSS MUCH OF SOUTH CENTRAL AND SOUTHEAST MINNESOTA AND EASTERN IOWA. THE HIGHEST SNOW TOTAL /MAINLY DUE TO THE AXIS PIVOTING ACROSS THIS AREA FOR A LONG DURATION/ WAS 11 INCHES 8 MILES WEST OF FARIBAULT. OUR HIGHEST TOTAL IS 3.8 INCHES IN MANTORVILLE MINNESOTA /DODGE COUNTY/. FOR TONIGHT...THE 26.12Z MODELS ARE IN GOOD AGREEMENT THAT THE TROUGH WILL CONTINUE TO PULL SOUTH AWAY FROM THE AREA AND TAKE WITH IT THE INVERTED TROUGH WITH IT. THEY ALSO SHOW THAT THE ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. THIS FRONT WILL LIKELY EXTEND FROM WISCONSIN RAPIDS TO OELWEIN IOWA AROUND MIDNIGHT AND WILL BE SOUTH OF THE FORECAST AREA BY 3 AM. THE MODELS SHOW THAT THAT THE 900 TO 700 FRONTOGENESIS WILL QUICKLY WEAKEN ACROSS THE AREA THIS EVENING. AS A RESULT...WENT WITH A RAPIDLY DIMINISHING TREND IN THE SNOW. ADDITIONAL TOTALS WILL BE UP TO AN INCH IN NORTHEAST IOWA AND SOUTHEAST MINNESOTA...AND FROM A TRACE TO A HALF INCH IN WESTERN WISCONSIN. WITH IT STILL SNOWING...WILL JUST LET THE WINTER WEATHER ADVISORY CONTINUE THROUGH 6 PM. WITH STRONG COLD AIR ADVECTION IN THE WAKE OF THIS FRONT...EXPECT HIGH TEMPERATURES FOR THANKSGIVING TO OCCUR BETWEEN MIDNIGHT AND 3 AM TONIGHT. NAEFS STANDARD 850 MB TEMPERATURE ANOMALIES ARE RUNNING AROUND 2 STANDARD DEVIATIONS BELOW NORMAL. AS A RESULT...EXPECT HIGH TEMPERATURES TO RANGE FROM NEAR 10 TO 25. THIS WILL BE THE COLDEST THANKSGIVING IN SOUTHEAST MINNESOTA AND NORTHEAST IOWA SINCE 1985...AND THE COLDEST IN WESTERN WISCONSIN SINCE 1958. MORE ON THIS CAN BE FOUND IN THE CLIMATE SECTION OF THIS PRODUCT. .LONG TERM...(THURSDAY NIGHT THROUGH WEDNESDAY) ISSUED AT 351 PM CST WED NOV 26 2014 ON THURSDAY NIGHT AND FRIDAY...MODERATE TO STRONG 925 TO 700 MB WARM AIR ADVECTION WILL DEVELOP ACROSS THE AREA AS A SHORT WAVE TROUGH MOVES EAST ACROSS NORTHERN MINNESOTA. IT CONTINUES TO LOOK LIKE THIS SYSTEM WILL PRODUCE BETWEEN 1.5 AND 3 INCHES ALONG AND NORTH OF INTERSTATE 94...AND FROM A TRACE TO 1.5 INCHES SOUTH OF THIS INTERSTATE. SOUNDINGS CONTINUE TO SHOW THAT DRY AIR ABOVE 850 MB WILL MOVE NORTHEAST INTO THE AREA FROM THE CENTRAL PLAINS ON FRIDAY. THIS DRY AIR WILL SHUTOFF ICE CRYSTAL SEEDING FROM ALOFT. HOWEVER THERE APPEARS TO BE A DEEP ENOUGH COLD LAYER NEAR THE SURFACE THAT SOME SNOW COULD STILL DEVELOP INITIALLY...AND THEN AS THIS LAYER WARMS UP THIS PRECIPITATION COULD POTENTIALLY SHIFT OVER TO SOME LIGHT FREEZING DRIZZLE...BUT A BIT CONCERNED THAT BY THIS TIME THERE MAY BE ENOUGH DRY IN THE LOW LEVELS TO PRECLUDE THIS FROM HAPPENING. ON FRIDAY NIGHT...THE NAM DEVELOPS FREEZING RAIN NEAR THE INTERSTATE 90 CORRIDOR. MEANWHILE THE OTHER DETERMINISTIC MODELS HAVE THE AREA DRY...SO TRENDED THE FORECAST TOWARD THEM. ANOTHER ISSUE ON FRIDAY NIGHT IS THAT THE LOW TEMPERATURES LOOK TOO COLD CONSIDERING SOUTHWEST WIND OF 10 TO 15 MPH AND THE MODELS LOOKING LIKE THEY HAVE TOO MUCH SNOW INITIALIZED IN THEM. THE NAM IN PARTICULAR IS ABOUT 2 TO 3 INCHES TOO HIGH WITH ITS SNOW DEPTH ALREADY. DUE TO THIS...RAISED THEM A FEW DEGREES AND ALSO RAISED SATURDAY MAXIMUM TEMPERATURES TOO. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z THURSDAY AFTERNOON) ISSUED AT 1130 AM CST WED NOV 26 2014 SNOW HAS BEEN FALLING AT RST FOR THE PAST FEW HOURS AND WILL CONTINUE AT THIS INTENSITY THROUGH THE EARLY HALF OF THE AFTERNOON WITH VISIBILITY STAYING DOWN BETWEEN 3/4-2SM. THIS SNOW IS EXPECTED TO MAKE IT INTO LSE AROUND 21Z OR SO...BUT LIKELY WILL NOT BE AS INTENSE AT 2SM OR HIGHER. CONDITIONS WILL IMPROVE LATER THIS AFTERNOON AND EVENING AFTER THE COLD FRONT MOVES IN AND BRINGS DRIER AIR DOWN FROM THE NORTH. SOME MVFR CEILINGS WILL LIKELY HOLD ON THROUGH THE NIGHT BEFORE SCATTERING OUT TOMORROW MORNING AS A RIDGE OF HIGH PRESSURE MOVES IN FROM THE WEST. && .CLIMATE...THANKSGIVING ISSUED AT 351 PM CST WED NOV 26 2014 WITH A HIGH TEMPERATURE NEAR 10 DEGREES...ROCHESTER MINNESOTA WILL BE WITHIN THE TOP 5 FOR THEIR COLDEST THANKSGIVING HIGH TEMPERATURE. THEY ARE... 1/ 7F 1930 2/ 12F 1985 3/ 14F 1952 4/ 14F 1886 5/ 17F 1956 17F 1919 IT WILL BE ONLY THE 10TH TIME THAT ROCHESTER HAS BEEN 19 DEGREES OR COLDER ON THANKSGIVING. THE LAST TIME IT OCCURRED WAS 1985. IN LA CROSSE WISCONSIN...THERE IS STILL SOME QUESTION ON WHETHER THE HIGH FOR THE DAY WILL BE IN THE TEENS OR NOT. AT MIDNIGHT...THE HRRR...NAM...SREF...AND RAP HAVE THE HIGH TEMPERATURE BETWEEN 20 AND 22F. MEANWHILE BOTH THE GFS AND ECMWF...HAS A MIDNIGHT HIGH OF 18F. THIS WOULD PLACE THIS THANKSGIVING IN THE 9 TO 15 RANK. THEY ARE... 7/ 17F 1919 17F 1952 9/ 19F 1958 19F 1956 19F 1952 12/ 20F 1938 20F 1905 20F 1881 15/ 21F 1903 16/ 23F 1877 THE COLDEST IS 4 DEGREES IN 1872. OUR TEMPERATURE RECORDS FOR LA CROSSE STARTED JUST OVER A MONTH BEFORE THIS RECORD WAS SET ON OCTOBER 15 1872. IF WE ARE IN THE TEENS FOR A HIGH TEMPERATURE IT WILL ONLY BE THE 11TH TIME THAT THIS HAS OCCURRED. IT WILL DEFINITELY BE THE COLDEST THANKSGIVING AS FAR AS HIGH TEMPERATURE SINCE 1958 /19F/. ALSO THIS COULD POTENTIALLY BE THE 21ST CONSECUTIVE THANKSGIVING WITHOUT MEASURABLE PRECIPITATION IN LA CROSSE. THIS STRETCH IS THE LONGEST. PRIOR TO THIS STRETCH...THE RECORD WAS 6 YEARS /1900-1905 1909-14 AND 1986-91/. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR MNZ086- 094. IA...WINTER WEATHER ADVISORY UNTIL 6 PM CST THIS EVENING FOR IAZ008- 018-019. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION...HALBACH CLIMATE...BOYNE
AREA FORECAST DISCUSSION
NWS CHEYENNE WY
1029 PM MST TUE NOV 25 2014 .UPDATE... ISSUED AT 1016 PM MST TUE NOV 25 2014 WYDOT SENSORS OVER THE SOUTH LARAMIE RANGE LATE THIS EVENING ARE REPORTING WIND SPEEDS IN THE 30 MPH RANGE OVER THE SUMMIT. LATEST WRKHGT PRODUCT EASING CRAIG TO CASPER 850 AND 700MB HEIGHT GRADIENTS OVERNIGHT BEFORE PICKING THEM UP AGAIN TOMORROW AFTERNOON. WENT AHEAD AND CANCELLED THE HGH WIND WARNING FOR THE SOUTH LARAMIE RANGE EARLY WITH THIS UPDATE. DID KEEP THE ARLINGTON ZONE GOING AS FORECAST AS THEIR WINDS OUT THERE ARE GUSTING TO THE LOW 40S. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 805 PM MST TUE NOV 25 2014 SEEING RAPIDLY COOLING CLOUD TOPS ON IR IMAGERY ACROSS NORTH CENTRAL WYOMING THIS EVENING JUST NORTH OF CONVERSE COUNTY. WEBCAMS NEAR NATURAL BRIDGE SHOWING I-25 SNOW COVERED WITH REDUCED VISIBILITIES. GOT A REPORT OUT OF DOUGLAS OF 3 INCHES OF SNOW...SO WENT AHEAD AND ADDED CONVERSE COUNTY TO THE WINTER WEATHER ADVISORY. LOOKING AT WIND REPORTS FURTHER SOUTH...FRONT ALREADY HAS MADE IT THROUGH BORDEAUX AND WINDS OUT WEST IN CARBON AND NORTHERN ALBANY COUNTIES CONTINUE TO DECREASE. WENT AHEAD AND CANCELLED THE HIGH WIND WARNING FOR THESE AREAS EARLY. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 700 PM MST TUE NOV 25 2014 LOOKING AT AREA WYDOT AND METAR OBSERVATIONS...DECIDED TO LET THE HIGH WIND WARNINGS FOR MOST OF LARAMIE COUNTY...THE LARAMIE VALLEY AND THE SARATOGA AREA EXPIRE ON TIME AT 7 PM THIS EVENING. PROBABLY COULD HAVE TAKEN BORDEAUX OUT OF THE WARNING AS WELL...BUT WILL WAIT ANOTHER HOUR OR SO TO SEE WHAT THEIR WINDS DO UP THERE. && .SHORT TERM...(THIS EVENING THROUGH WEDNESDAY NIGHT) ISSUED AT 342 PM MST TUE NOV 25 2014 FORECAST REMAINS ON TRACK FOR THE MOST PART REGARDING STRONG WINDS AND SNOW PER UPDATED DISCUSSION ISSUED EARLIER THIS AFTERNOON. THE COLD FRONT HAS MOVED SOUTH ABOUT HALFWAY-THREE QUARTERS THROUGH THE CWA AT THIS HOUR...WITH SNOW AND LIGHT SHOWERS INCREASING IN COVERAGE AS IT PASSES THROUGH. RAIN SHOULD QUICKLY CHANGE TO SNOW AS COOLER AIR FILTERS IN BEHIND THE FRONT. STRONG WINDS CONTINUE THIS AFTERNOON MAINLY ALONG AND WEST OF THE LARAMIE RANGE WITH WINDS A BIT CALMER ACROSS THE WYO PLAINS AT THIS HOUR. WILL LEAVE WIND HIGHLIGHTS AS IS AT LEAST UNTIL FRONTAL PASSAGE. MADE A FEW CHANGES TO THE WINTER WEATHER ADVISORY TO INCLUDE THE SUMMIT AND EXTEND THE TIMING OF THE HIGHLIGHT TO THE AFTERNOON TO ACCOUNT FOR BLOWING SNOW CONCERNS. AFTER A FURTHER LOOK AT THE WIND PROGS FOR TOMORROW MORNING...AND DISCUSSION WITH OUR PARTNERS ABOUT POTENTIAL TRAVEL IMPACTS UP AT THE SUMMIT WITH THE COMBO OF SNOW AND WIND...FELT IT NECESSARY TO ADJUST THE ADVISORY FOR THESE TWO CHANGES. 2 TO 5 INCHES STILL LOOKS TO BE ON TRACK FOR SNOW TOTALS ACROSS THE AREA...BUT WINDS OF 15 TO 20 MPH INCREASING TO 25 TO 35 MPH WITH HIGHER GUSTS BY SUNRISE UP NEAR THE SUMMIT AS THE SNOW ENDS WILL LIKELY CAUSE SOME TRAVEL PROBLEMS THROUGH THE MORNING DUE TO BLOWING AND DRIFTING OF SNOW. WINDS WILL INCREASE ACROSS THE EASTERN FOOTHILLS AND ADJACENT PLAINS IN THE MORNING AS WELL WHERE THE HEAVIER SNOW IS EXPECTED TO FALL...SO COULD SEE SOME HAZARDOUS TRAVEL ALONG I-25 AND I-80 APPROACHING CHEYENNE DUE TO BLOWING AND DRIFTING OF SNOW. EXTENDING THE TIMING THROUGH 2 PM AS BLOWING SNOW SHOULD BE LESS OF A CONCERN IN THE AFTERNOON AS WINDS AND SOME HEATING THROUGH THE DAY WORK OVER THE SNOWPACK. BREEZY TO WINDY CONDITIONS WILL CONTINUE THROUGH WEDNESDAY NIGHT AS THE LLVL GRADIENT REMAINS TIGHT IN THE WAKE OF THE DEPARTING FRONT. .LONG TERM...(THURSDAY THROUGH TUESDAY) ISSUED AT 342 PM MST TUE NOV 25 2014 MAIN STORY THROUGH LATE WEEK WILL BE HIGH WIND POTENTIAL IN THE MAIN WIND CORRIDORS ACROSS SOUTHEAST WY. MEDIUM RANGE MODELS ARE STILL IN GOOD AGREEMENT WITH A FAVORABLE PATTERN FOR STRONG GUSTS WITH AN H25 JET CORE REMAINING ANCHORED OVER THE NORTHERN ROCKIES WITH WEAK SFC LOW PRESSURE SPREADING ACROSS MT INTO THE DAKOTAS. THIS PRETTY MUCH KEEPS THE LLVL CAG-CPR GRADIENTS BETWEEN 60 AND 70 METERS THROUGH AT LEAST FRIDAY. WITH THE GFS SHOWING A WIDESPREAD AREA OF 50 KT 700 MB FLOW...INCREASED WINDS AND KEPT GUSTS RIGHT AROUND WARNING CRITERIA THROUGH THE END OF THE WEEK FOR ARLINGTON/BORDEAUX AND I80 BETWEEN LARAMIE AND CHEYENNE. ASIDE FROM THE WIND...CONFIDENCE IS HIGH IN A RATHER WARM THANKSGIVING. BOTH THE GFS AND ECMWF SUGGEST H7 TEMPS IN THE 2-3 DEG C RANGE. WESTERLY DOWNSLOPE WINDS WOULD FAVOR THE WARMER MOS WITH HIGHS AROUND 60-65 F OVER THE PLAINS ON THU/FRI. A CANADIAN SFC HIGH WILL BEGIN TO SINK SOUTH INTO THE NORTHERN HIGH PLAINS INTO SAT...PUSHING THE BEST SFC PRESSURE GRADIENTS SOUTH OF THE CWA AND PROVIDING A BREAK FROM HIGH WINDS BY LATE IN THE WEEKEND. A POTENT SHORTWAVE WILL SWING ACROSS THE DAKOTAS ON SUN...SENDING A BACKDOOR FRONT SOUTHWESTWARD. SOME DIFFERENCES IN THE GFS/ECM WITH THE DEPTH OF COLD AIR. THE COLDER ECMWF SHOWS TEMPS AROUND -9C AT 700 MB IN THE NORTHERN PANHANDLE AT 18Z SUN...WHEREAS THE GFS ONLY SHOWS -3C AT THE SAME TIME. STILL LEANED MORE TOWARD THE ECMWF AND MADE FEW CHANGES TO THE PREVIOUS FCST. GENERALLY A DRY PERIOD WITH A LACK OF ANY SUBSTANTIAL DYNAMICS. PRECIP CHANCES LOOK TO INCREASE ALONG AND WEST OF THE LARAMIE RANGE ON TUE AND WED WITH THE RETURN OF MOIST SOUTHWEST FLOW ALOFT PER MEDIUM RANGE GUIDANCE. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z WEDNESDAY NIGHT) ISSUED AT 1016 PM MST TUE NOV 25 2014 LATEST HRRR GUIDANCE USED FOR THIS TAF PACKAGE. FRONT CONTINUES TO PUSH SOUTHWEST OVERNIGHT WITH SNOW DEVELOPING WEST OF THE LARAMIE RANGE. LARAMIE ALREADY DOWN TO LESS THAN 2 MILES IN SNOW AND WOULD EXPECT THIS TO CONTINUE THROUGH 12Z BEFORE IMPROVING. HRRR SHOWING KRWL STAYING DOWN...THOUGH MOST LIFR/IFR SOUTH OF THE AIRPORT. ANOTHER WINDY DAY FOR WEDNESDAY. && .FIRE WEATHER... ISSUED AT 342 PM MST TUE NOV 25 2014 WINDY CONDITIONS WILL DIMINISH TONIGHT AS A COLD FRONT MOVES THROUGH THE AREA. A PERIOD OF SNOW WILL FALL TONIGHT WITH ACCUMULATIONS OF 2 TO 5 INCHES EXPECTED ACROSS LOWER ELEVATIONS IN SOUTHEAST WYOMING. THE SNOWY AND SIERRA MADRE RANGES WILL SEE UP TO ANOTHER FOOT OF SNOW THROUGH TONIGHT. && .CYS WATCHES/WARNINGS/ADVISORIES... WY...WINTER STORM WARNING UNTIL 7 AM MST WEDNESDAY FOR WYZ112-114. HIGH WIND WARNING UNTIL 2 PM MST WEDNESDAY FOR WYZ110. WINTER WEATHER ADVISORY UNTIL 2 PM MST WEDNESDAY FOR WYZ101-103- 106-107-116>119. NE...NONE. && $$ UPDATE...GCC SHORT TERM...RJM LONG TERM...CLH AVIATION...GCC FIRE WEATHER...RJM
AREA FORECAST DISCUSSION
NWS TAMPA BAY RUSKIN FL
400 AM EST FRI NOV 28 2014 .SYNOPSIS... 09Z WATER VAPOR AND H4 RAP ANALYSIS SHOW A SLOWLY DEAMPLIFYING UPPER LEVEL PATTERN ACROSS THE CONUS. BROAD LONGWAVE RIDGING IS IN PLACE FROM THE PACIFIC COAST TO THE CENTRAL PLAINS...FOLLOWED DOWNSTREAM BY A LONGWAVE TROUGH EXITING THE ATLANTIC SEABOARD AND NORTHEASTERN STATES. THE FLORIDA PENINSULA RESIDES NEAR THE VERY BASE OF THIS EXITING TROUGH WITH A GENERAL W/NW MID/UPPER LEVEL FLOW. THIS CYCLONIC FLOW WILL BE REPLACED BY A BUILDING RIDGE DURING THE UPCOMING WEEKEND...AND TEMPERATURES WILL BE MODERATING ALONG WITH THE BUILDING HEIGHTS. THE 28/00Z KTBW SOUNDING PROFILE REMAINS INCREDIBLY DRY WITH A CALCULATED PW VALUE OF ONLY AROUND 0.25". THIS READING IS SLIGHTLY UP FROM THE COLUMN 24 HOURS AGO...BUT STILL NEAR THE VERY BOTTOM OF THE CLIMATOLOGICAL RANGE DURING LATE NOVEMBER. LARGE DEWPOINT DEPRESSION EXIST FROM TH SURFACE ALL THE WAY UP TO THE TROP...AND IT IS LITTLE WONDER GIVEN THIS PROFILE THAT OUR SKIES ARE CLEAR EARLY THIS MORNING. AT THE SURFACE...1031MB HIGH PRESSURE IS CENTERED TO OUR NORTH OVER THE DEEP SOUTH. THIS HIGH IS SLIDING EAST TOWARD THE GA/CAROLINA COAST AND WILL SLOWLY TURN OUR WINDS FROM THE CURRENT NORTHERLY DIRECTION TO THE NORTHEAST THROUGH THE DAY. OUR DISTANCE FROM THE HIGH CENTER IS KEEPING OUR GRADIENT ENOUGH THAT THE BOUNDARY LAYER IS HAVING DIFFICULTLY DECOUPLING EARLY THIS MORNING...AND THE RESULTING LIGHT BREEZE IS KEEPING TEMPS FROM DROPPING FAST. HOWEVER...WINDS ARE GENERALLY LIGHT (UNDER 10 MPH). THE SLOW TEMPERATURE DROP AND ONLY LIGHT WINDS IS MAKING THE WIND CHILL ADVISORY FOR PORTIONS OF THE CENTRAL PENINSULA A REALLY "BORDERLINE" EVENT. A FEW SPOTS MAY EVENTUALLY SEE WIND CHILLS DOWN AROUND 35 BRIEFLY TOWARD DAWN...BUT DOES NOT LOOK LIKE WE WILL SEE WIDESPREAD CONDITIONS REACH ADVISORY LEVELS. WILL BE DROPPING THE ADVISORY WITH THE 4AM FORECAST PACKAGE. REGARDLESS OF WHETHER WE BRIEFLY REACH ADVISORY CRITERIA...IT WILL STILL BE A BIT CHILLY OUT THERE UNTIL THE SUN CAN RISE AND START WORKING ON THE ATMOSPHERE. SO... DRESS APPROPRIATELY IF YOU ARE OUT THIS MORNING...PERHAPS WAITING OUTSIDE YOUR FAVORITE STORE ON THIS FRIDAY AFTER THANKSGIVING. && .SHORT TERM (TODAY THROUGH SATURDAY)... A QUIET PERIOD OF SENSIBLE WEATHER IN OUR FUTURE THROUGH THE UPCOMING WEEKEND...WITH DRY CONDITIONS AND MODERATING TEMPERATURES. TODAY AND TONIGHT ... A PLEASANT...BUT COOL LATE NOVEMBER DAY ON TAP FOR THE REGION. SURFACE HIGH PRESSURE WILL BECOME ESTABLISHED TO OUR NORTH WHILE IN THE UPPER LEVELS THE EASTERN CONUS TROUGH CONTINUES TO DEAMPLIFY AS IT PROGRESSES OFF INTO THE WESTERN ATLANTIC. CHILLY CONDITIONS EARLY IN THE MORNING WILL MODERATE UNDER NEAR 100% OF THE POSSIBLE SUNSHINE TO THE UPPER 50S FAR NORTH...LOWER 60S ALONG THE I-4 CORRIDOR...AND MIDDLE 60S DOWN TOWARD FORT MYERS. TONIGHT...SURFACE HIGH WILL BECOMES CENTERED ALONG THE GA/CAROLINA COAST AND THEN RIDGES BACK W/SW INTO NORTHERN FLORIDA. THE ATMOSPHERE WILL NOT HAVE RECOVERED MUCH...AND THE DRY COLUMN WILL ONCE AGAIN ALLOW FOR A CHILLY NIGHT...WITH WIDESPREAD LOW TEMPERATURES IN THE 40S FOR CENTRAL AND SOUTHERN ZONES...AND 30S FOR THE NATURE COAST ZONES. THE CLOSER PROXIMITY TO THE RIDGE AXIS FOR THE ZONES NORTH OF TAMPA WILL ALLOW FOR THE POTENTIAL FOR MORE SHELTERED AREAS TO DECOUPLE AFTER MIDNIGHT...AND RADIATE DOWN INTO THE LOWER/MIDDLE 30S BY SUNRISE. BEST CHANCES AT DECOUPLING AND LOWER/MIDDLE 30S WILL BE NORTH OF BROOKSVILLE...AND THESE AREAS WILL ALSO HAVE THE GREATEST RISK OF PATCHY FROST DURING THE EARLY MORNING HOURS. SATURDAY... UPPER PATTERN BEGINS TO SHOW THE SIGNS OF RIDGING OVER THE CENTRAL/EASTERN GULF WHICH WILL EVOLVE AND AMPLIFY EASTWARD OVER OUR REGION LATER SATURDAY/SATURDAY NIGHT. WITH THE STACKED RIDGING DEVELOPING OVERHEAD...TEMPERATURES WILL RESPOND NICELY...AND CURRENTLY FORECASTING AFTERNOON HIGHS ON SATURDAY CLOSE TO 10 DEGREES WARMER FOR MOST LOCATIONS THAN THEY WILL BE THIS AFTERNOON. THIS EQUATES TO UPPER 60S FAR NORTH...LOWER 70S THROUGH THE I-4 CORRIDOR AND MIDDLE 70S DOWN TOWARD FORT MYERS. THE WARMUP AND DRY CONDITIONS CONTINUE FOR THE REST OF THE WEEKEND...BUT MORE ON THAT PERIOD IN THE LONG TERM DISCUSSION BELOW. HAVE A GREAT FRIDAY! STAY WARM IF YOU ARE OUT FOR AN EARLY MORNING SHOPPING EXCURSION. && .LONG TERM (SUNDAY THROUGH NEXT THURSDAY)... ALOFT - A BROAD LOW ACROSS NUNAVUT CANADA TROUGHED DOWN ACROSS THE PRAIRIES OF CENTRAL CANADA INTO THE PACIFIC NORTHWEST...A SHORTWAVE TROUGH WAS OVER THE BIG BEND REGION OF TX...AND A RIDGE OVER THE GULF OF MEXICO REACHED NORTH ACROSS THE OHIO VALLEY. SURFACE - HIGH PRESSURE OVER THE SOUTHERN CANADIAN ROCKIES SPILLED DOWN OVER THE NORTHERN U.S. PLAINS...A TROUGH/FRONTAL BOUNDARY STRETCHED FROM ONTARIO TO THE CENTRAL HIGH PLAINS...AND HIGH PRESSURE CENTERED OFF THE EASTERN SEABOARD RIDGED ACROSS GA/FL INTO MUCH OF THE GULF OF MEXICO. THROUGH MON - THE UPPER TROUGH ROTATES ALONG THE NORTHERN TIER OF THE CONUS TO THE GREAT LAKES WHILE THE TX SHORT WAVE TROUGH SLIDES OUT OVER THE GULF OF MEXICO WITH THE RIDGE MOVING OUT OVER THE ATLANTIC. THE CANADIAN SURFACE HIGH MOVES INTO THE UPPER MIDWEST WITH THE TROUGH OR FRONT SHIFTING EASTWARD...ARCING ALONG A WESTERN GULF COAST-NEW ENGLAND LINE. THE HIGH PRESSURE OFF THE EASTERN SEABOARD RE-ADJUSTS TO ALONG LATITUDE 30-35 NORTH BUT CONTINUES TO RIDGE BACK WEST TO THE CENTRAL GULF COAST. FOR TUE-THU - ANOTHER SHORT WAVE TROUGH FORMS OVER WESTERN CANADA AND MOVES ALONG THE INTERNATIONAL LINE WITH CYCLONIC FLOW FOR MUCH OF THE CENTRAL AND EASTERN CONUS. THE GULF SHORT WAVE TROUGH CROSSES FL AND MOVES OVER THE BAHAMAS...LEAVING NEARLY ZONAL FLOW OVER THE GULF OF MEXICO AS RIDGING BEGINS MOVING EAST FROM MEXICO. THE MIDWEST SURFACE HIGH STRETCHES OUT TO THE SOUTHWEST AS IT TRACKS EAST TO THE EASTERN SEABOARD AND GULF OF MEXICO BY THE END OF THE PERIOD...REINFORCING/MERGING WITH THE RIDGE FROM THE ATLANTIC. THE TROUGH/FRONT SETTLES IN ACROSS THE SOUTHEAST U.S. AND DISSIPATES. THE UPPER RIDGING MOVING BY FOLLOWED EVENTUALLY BY ZONAL FLOW WILL KEEP A DRY AND STABLE AIRMASS IN PLACE WITH A DRY FORECAST FOR THE MOST PART. THE EXCEPTION WILL BE TUE AND TUE NIGHT WHEN THE SHORT WAVE PASSES BY. IT WILL BE ON THE WEAK SIDE BUT WITH ENOUGH ENERGY THAT COMBINES WITH ADDITIONAL MOISTURE STREAMING IN FROM THE EAST TO RESULT IN SOME LOW CHANCE SHOWERS MAINLY INTERIOR. TEMPERATURES START OFF COOL SUN MORNING THEN WARM WITH READINGS RUNNING JUST ON THE WARM SIDE OF NORMAL. THE POSITION OF SURFACE HIGH PRESSURE TO THE NORTH AND NORTHEAST OF THE ARE WILL MAINTAIN NORTHEASTERLY AND EASTERLY WINDS...ROBUST AT TIMES ESPECIALLY ON THE GULF. && .AVIATION... VFR CONDITIONS ARE EXPECTED THROUGH THE FORECAST PERIOD. && .MARINE... SMALL CRAFT ADVISORY CONDITIONS EXIST ACROSS MOST OF THE COASTAL WATERS EARLY THIS MORNING. EXPECT THESE HAZARDOUS BOATING CONDITIONS TO CONTINUE THROUGH THE EARLY MORNING...WITH CONDITIONS BEGINNING TO IMPROVE SLOWLY THROUGH THE DAYLIGHT HOURS TODAY. ONCE THE ADVISORY IS DONE LATER TODAY...CAUTIONARY LEVEL WINDS ARE LIKELY TO PERSIST THROUGH FRIDAY NIGHT FOR AREAS TO THE SOUTH OF TARPON SPRINGS. EASTERLY FLOW IS THEN EXPECTED TO PERSIST THROUGH THE REMAINDER OF THE FORECAST PERIOD. && .FIRE WEATHER... HIGH PRESSURE WILL REMAIN PARKED TO THE NORTH OF THE REGION THROUGH THE UPCOMING WEEKEND. DRIER AIR IS FILTERING INTO THE REGION BEHIND A COLD FRONT THAT PASSED THROUGH DURING THURSDAY. RELATIVE HUMIDITY VALUES THIS AFTERNOON WILL DROP INTO THE MIDDLE AND UPPER 30S FOR MUCH OF THE REGION...WITH A FEW SPOTS LIKELY DROPPING BELOW 35 PERCENT FOR A BRIEF TIME. HOWEVER...DURATIONS OF SUB 35 PERCENT RELATIVE HUMIDITY WILL BE SHORT...AND WINDS WILL GENERALLY REMAIN BELOW CRITICAL LEVELS. THEREFORE NO RED FLAG CONDITIONS ARE ANTICIPATED. LOW LEVEL MOISTURE BEGINS TO RECOVER OVER THE WEEKEND AND WILL HELP KEEP RELATIVE HUMIDITY VALUES ABOVE CRITICAL LEVELS FOR BOTH SATURDAY AND SUNDAY. FOG POTENTIAL...FOG IS NOT EXPECTED TO BE A CONCERN FRIDAY NIGHT. CONDITIONS BECOME SLIGHTLY MORE FAVORABLE AND HENCE HIGHER CHANCES EXIST FOR AREAS OF FOG DEVELOPMENT BOTH SATURDAY NIGHT AND SUNDAY NIGHT. && .PRELIMINARY POINT TEMPS/POPS... TPA 61 46 72 56 / 0 0 0 0 FMY 66 49 75 58 / 0 0 0 0 GIF 62 45 71 55 / 0 0 0 0 SRQ 63 46 73 56 / 0 0 0 0 BKV 60 37 71 48 / 0 0 0 0 SPG 61 50 71 60 / 0 0 0 0 && .TBW WATCHES/WARNINGS/ADVISORIES... FL...NONE. GULF WATERS...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR BONITA BEACH TO ENGLEWOOD OUT 20 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 NM-TARPON SPRINGS TO SUWANNEE RIVER OUT 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR BONITA BEACH TO ENGLEWOOD OUT 20 TO 60 NM-ENGLEWOOD TO TARPON SPRINGS OUT 20 TO 60 NM. SMALL CRAFT ADVISORY UNTIL 7 AM EST THIS MORNING FOR CHARLOTTE HARBOR AND PINE ISLAND SOUND-TAMPA BAY WATERS. && $$ SYNOPSIS/SHORT TERM/MARINE/AVIATION/FIRE WX...MROCZKA LONG TERM/DECISION SUPPORT...RUDE
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
350 AM EST FRI NOV 28 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 332 AM EST FRI NOV 28 2014 HIGH PRESSURE WILL REMAIN IN CONTROL OVER THE AREA THROUGH TONIGHT. THIS WILL RESULT IN DRY BUT COLD WEATHER FOR INDIANA. THE HIGH WILL BEGIN TO DRIFT EAST OF INDIANA LATER TODAY. THIS WILL ALLOW WARMER SOUTHERLY FLOW TO RETURN TO CENTRAL INDIANA IN ADDITION TO CHANCES FOR SHOWERS AS FIRST A WARM FRONT LIFTS NORTH OVER THE AREA...FOLLOWED BY A COLD FRONT SUNDAY NIGHT. DRY AND COLD WEATHER WILL RETURN TO THE AREA BEHIND THE FRONT ON MONDAY NIGHT. THEN SLOWLY THROUGH MID WEEK TEMPERATURES WILL WARM BACK TO NORMAL VALUES FOR THIS TIME OF YEAR. NEXT CHANCE FOR PRECIPITATION WILL BE THURSDAY AND FRIDAY AS A SYSTEM FROM THE PLAINS MOVES INTO THE AREA. && .NEAR TERM /TODAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 SHORT TERM GUIDANCE DID NOT HAVE A VERY GOOD HANDLE ON THE FLURRIES/BORDERLINE LIGHT SNOW SHOWERS WHICH OCCURRED OVER CENTRAL INDIANA FOR MOST OF THANKSGIVING DAY AND NIGHT...AND HAVE SINCE EXITED THE REGION. KNOWING THIS...AND SEEING THE HRRR AND SREF DEVELOPING LIGHT PRECIP RETURNS MOVING INTO CENTRAL INDIANA FROM ILLINOIS EARLY THIS MORNING...SERIOUSLY CONSIDERED PUTTING IN AT LEAST A MENTION OF FLURRIES. AS IS CUSTOMARY WITH THESE TYPE OF LIGHT WINTRY PRECIP SITUATIONS THE REST OF THE SHORT TERM GUIDANCE IS SHOWING NOTHING BUT COMPLETELY DRY AND PARTLY CLOUDY SKY CONDITIONS TODAY. BASED ON TRENDS UPSTREAM...IT DOES NOT APPEAR THESE RETURNS ARE MAKING IT TO THE SURFACE SO WILL REFRAIN FROM EVEN PUTTING FLURRIES IN THE FORECAST AT THIS TIME. HOWEVER WILL NEED TO PAY CLOSE ATTENTION THROUGH EARLY THIS MORNING TO SEE IF FLURRIES OR EVEN -SN NEEDS TO BE INCLUDED IN THE FORECAST. OTHERWISE...AFTER THIS MORNING/S POTENTIAL FOR FLURRIES...THE REST OF TODAY LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE BEGINS TO SHIFT EAST OF THE REGION. SKIES PARTLY CLOUDY ACROSS THE SOUTH TO MOSTLY CLOUDY FOR FAR NORTHERN COUNTIES AS THIS AREA IS CLOSER TO AN UPPER WAVE THAT WILL BE MOVING THROUGH THE GREAT LAKES. BLEND OF GUIDANCE SEEMS REASONABLE FOR HIGHS 33 (NORTHEAST) TO LOW 40S (SOUTHWEST CWA). && .SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/... ISSUED AT 332 AM EST FRI NOV 28 2014 TONIGHT DRY AND COLD CONDITIONS WILL PREVAIL. ONLY DIFFERENCE IS THE LOWS WILL ACTUALLY BE CLOSER TO NORMAL THANKS TO THE CHANGE TO SOUTHERLY LOW LEVEL FLOW ON THE BACKSIDE OF THE HIGH PRESSURE. TEMPERATURES WILL JUST KEEP ON CLIMBING RIGHT THROUGH THIS WEEKEND AS STRONG WARM AIR CONTINUES TO ADVECT INTO THE REGION AS A SURFACE WARM FRONT LIFTS NORTH OVER THE AREA ON SATURDAY. MODELS HAVE BEEN HINTING AT SOME WEAK CHANCE FOR SHOWERS ASSOCIATED WITH THIS FEATURE AND SEEM TO BE IN AGREEMENT WITH AT LEAST SOME VERY LIGHT PRECIP POSSIBLE BEGINNING SATURDAY AFTERNOON AND CONTINUING THROUGH THE WEEKEND WITH VERY WEAK CHANCES UNTIL A COLD FRONT MOVES THROUGH ON SUNDAY NIGHT. THIS LATTER PORTION OF THE WEEKEND APPEARS TO HAVE THE BEST CHANCES FOR PRECIP CONSIDERING THE FORCING WITH THE FRONT AND HIGHER PWATS AND MOISTURE. FELT CONFIDENT ENOUGH TO INCREASE POPS TO AT LEAST WIDESPREAD CHANCE WITH EVEN LIKELY POPS ACROSS THE SOUTHEASTERN PORTION OF THE CWA SUNDAY NIGHT. AS FOR TEMPERATURE OVER THE WEEKEND LEANED TOWARD THE WARMER MAV GUIDANCE AND EVEN BUMPED UP HIGHS A DEGREE OR TWO BASED ON VERY STRONG WARM AIR ADVECTION. AND ACTUALLY INCREASED LOWS SLIGHTLY FOR SAME REASON...AND ALSO FACTORED IN CHANCES FOR PRECIP AND CLOUDY SKIES...ESPECIALLY FOR THE LATTER HALF OF THE WEEKEND. HIGHS SAT UPPER 40S TO MID 50S...FOR SUNDAY UPPER 50S TO LOW 60S. VERY IMPRESSIVE CONSIDERING NORMAL HIGHS ARE MID 40S. && .LONG TERM /MONDAY THROUGH THURSDAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 A FRONT SOUTH OF INDIANA AND AN UPPER WAVE MOVING THROUGH WILL KEEP CHANCES FOR A MIX OF RAIN AND SNOW IN THE FORECAST FOR MONDAY...BUT THESE CHANCES WILL DECREASE AS THE FRONT SINKS SOUTH AND THE WAVE MOVES OFF TO THE EAST. DRY WEATHER IS THEN EXPECTED MONDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGH PRESSURE MOVING ACROSS THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL DURING THIS TIME. MODELS ARE SHOWING SOME VARIABILITY FROM WEDNESDAY ON AND WITH A FAIRLY PROGRESSIVE PATTERN THERE IS LITTLE TO KEY IN ON SO WILL JUST ACCEPT INITIALIZATION...YIELDING SMALL CHANCES FOR RAIN THURSDAY WITH A WARM UP. && .AVIATION /DISCUSSION FOR THE 280900Z TAFS/... ISSUED AT 350 PM EST THU NOV 27 2014 AT KIND CEILINGS HAVE BEEN BOUNCING BETWEEN VFR AND MVFR AND HAD A TEMPO GROUP TO COVER THIS. THIS GROUP HAS ENDED BUT THINK WITH THE MID LEVEL CEILINGS ARRIVING SHORTLY THE MVFR CEILINGS WILL END AS WELL SO WILL NOT ADD THEM BACK IN AT THIS TIME. PREVIOUS DISCUSSION FOLLOWS... SATELLITE SHOWS LOWER CEILINGS 030-040 IN THE PROCESS OF BREAKING UP ACROSS THE AREA. APPEARS MOST OF THESE CEILINGS SHOULD SCATTER OUT AT THE TAF SITES BY ISSUANCE TIME...EXCEPT FOR KIND WHICH SHOULD SCATTER OUT WITHIN AN HOUR OR TWO AFTER ISSUANCE TIME. OTHERWISE...EXPECTING LAYERED CLOUDS ABOVE 050. LIGHT SURFACE WINDS OVERNIGHT SHOULD BECOME 170-190 DEGREES AT 8-11 KTS BY LATE MORNING FRIDAY. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...SMF NEAR TERM...SMF SHORT TERM...SMF LONG TERM...CP AVIATION...JAS/CP VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
337 AM EST FRI NOV 28 2014 .UPDATE... THE SYNOPSIS...NEAR TERM...SHORT TERM AND LONG TERM SECTIONS HAVE BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 332 AM EST FRI NOV 28 2014 HIGH PRESSURE WILL REMAIN IN CONTROL OVER THE AREA THROUGH TONIGHT. THIS WILL RESULT IN DRY BUT COLD WEATHER FOR INDIANA. THE HIGH WILL BEGIN TO DRIFT EAST OF INDIANA LATER TODAY. THIS WILL ALLOW WARMER SOUTHERLY FLOW TO RETURN TO CENTRAL INDIANA IN ADDITION TO CHANCES FOR SHOWERS AS FIRST A WARM FRONT LIFTS NORTH OVER THE AREA...FOLLOWED BY A COLD FRONT SUNDAY NIGHT. DRY AND COLD WEATHER WILL RETURN TO THE AREA BEHIND THE FRONT ON MONDAY NIGHT. THEN SLOWLY THROUGH MID WEEK TEMPERATURES WILL WARM BACK TO NORMAL VALUES FOR THIS TIME OF YEAR. NEXT CHANCE FOR PRECIPITATION WILL BE THURSDAY AND FRIDAY AS A SYSTEM FROM THE PLAINS MOVES INTO THE AREA. && .NEAR TERM /TODAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 SHORT TERM GUIDANCE DID NOT HAVE A VERY GOOD HANDLE ON THE FLURRIES/BORDERLINE LIGHT SNOW SHOWERS WHICH OCCURRED OVER CENTRAL INDIANA FOR MOST OF THANKSGIVING DAY AND NIGHT...AND HAVE SINCE EXITED THE REGION. KNOWING THIS...AND SEEING THE HRRR AND SREF DEVELOPING LIGHT PRECIP RETURNS MOVING INTO CENTRAL INDIANA FROM ILLINOIS EARLY THIS MORNING...SERIOUSLY CONSIDERED PUTTING IN AT LEAST A MENTION OF FLURRIES. AS IS CUSTOMARY WITH THESE TYPE OF LIGHT WINTRY PRECIP SITUATIONS THE REST OF THE SHORT TERM GUIDANCE IS SHOWING NOTHING BUT COMPLETELY DRY AND PARTLY CLOUDY SKY CONDITIONS TODAY. BASED ON TRENDS UPSTREAM...IT DOES NOT APPEAR THESE RETURNS ARE MAKING IT TO THE SURFACE SO WILL REFRAIN FROM EVEN PUTTING FLURRIES IN THE FORECAST AT THIS TIME. HOWEVER WILL NEED TO PAY CLOSE ATTENTION THROUGH EARLY THIS MORNING TO SEE IF FLURRIES OR EVEN -SN NEEDS TO BE INCLUDED IN THE FORECAST. OTHERWISE...AFTER THIS MORNING/S POTENTIAL FOR FLURRIES...THE REST OF TODAY LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE BEGINS TO SHIFT EAST OF THE REGION. SKIES PARTLY CLOUDY ACROSS THE SOUTH TO MOSTLY CLOUDY FOR FAR NORTHERN COUNTIES AS THIS AREA IS CLOSER TO AN UPPER WAVE THAT WILL BE MOVING THROUGH THE GREAT LAKES. BLEND OF GUIDANCE SEEMS REASONABLE FOR HIGHS 33 (NORTHEAST) TO LOW 40S (SOUTHWEST CWA). && .SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/... ISSUED AT 332 AM EST FRI NOV 28 2014 TONIGHT DRY AND COLD CONDITIONS WILL PREVAIL. ONLY DIFFERENCE IS THE LOWS WILL ACTUALLY BE CLOSER TO NORMAL THANKS TO THE CHANGE TO SOUTHERLY LOW LEVEL FLOW ON THE BACKSIDE OF THE HIGH PRESSURE. TEMPERATURES WILL JUST KEEP ON CLIMBING RIGHT THROUGH THIS WEEKEND AS STRONG WARM AIR CONTINUES TO ADVECT INTO THE REGION AS A SURFACE WARM FRONT LIFTS NORTH OVER THE AREA ON SATURDAY. MODELS HAVE BEEN HINTING AT SOME WEAK CHANCE FOR SHOWERS ASSOCIATED WITH THIS FEATURE AND SEEM TO BE IN AGREEMENT WITH AT LEAST SOME VERY LIGHT PRECIP POSSIBLE BEGINNING SATURDAY AFTERNOON AND CONTINUING THROUGH THE WEEKEND WITH VERY WEAK CHANCES UNTIL A COLD FRONT MOVES THROUGH ON SUNDAY NIGHT. THIS LATTER PORTION OF THE WEEKEND APPEARS TO HAVE THE BEST CHANCES FOR PRECIP CONSIDERING THE FORCING WITH THE FRONT AND HIGHER PWATS AND MOISTURE. FELT CONFIDENT ENOUGH TO INCREASE POPS TO AT LEAST WIDESPREAD CHANCE WITH EVEN LIKELY POPS ACROSS THE SOUTHEASTERN PORTION OF THE CWA SUNDAY NIGHT. AS FOR TEMPERATURE OVER THE WEEKEND LEANED TOWARD THE WARMER MAV GUIDANCE AND EVEN BUMPED UP HIGHS A DEGREE OR TWO BASED ON VERY STRONG WARM AIR ADVECTION. AND ACTUALLY INCREASED LOWS SLIGHTLY FOR SAME REASON...AND ALSO FACTORED IN CHANCES FOR PRECIP AND CLOUDY SKIES...ESPECIALLY FOR THE LATTER HALF OF THE WEEKEND. HIGHS SAT UPPER 40S TO MID 50S...FOR SUNDAY UPPER 50S TO LOW 60S. VERY IMPRESSIVE CONSIDERING NORMAL HIGHS ARE MID 40S. && .LONG TERM /MONDAY THROUGH THURSDAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 A FRONT SOUTH OF INDIANA AND AN UPPER WAVE MOVING THROUGH WILL KEEP CHANCES FOR A MIX OF RAIN AND SNOW IN THE FORECAST FOR MONDAY...BUT THESE CHANCES WILL DECREASE AS THE FRONT SINKS SOUTH AND THE WAVE MOVES OFF TO THE EAST. DRY WEATHER IS THEN EXPECTED MONDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGH PRESSURE MOVING ACROSS THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL DURING THIS TIME. MODELS ARE SHOWING SOME VARIABILITY FROM WEDNESDAY ON AND WITH A FAIRLY PROGRESSIVE PATTERN THERE IS LITTLE TO KEY IN ON SO WILL JUST ACCEPT INITIALIZATION...YIELDING SMALL CHANCES FOR RAIN THURSDAY WITH A WARM UP. && .AVIATION /DISCUSSION FOR THE 280600Z TAFS/... ISSUED AT 1139 PM EST THU NOV 27 2014 SATELLITE SHOWS LOWER CEILINGS 030-040 IN THE PROCESS OF BREAKING UP ACROSS THE AREA. APPEARS MOST OF THESE CEILINGS SHOULD SCATTER OUT AT THE TAF SITES BY ISSUANCE TIME...EXCEPT FOR KIND WHICH SHOULD SCATTER OUT WITHIN AN HOUR OR TWO AFTER ISSUANCE TIME. OTHERWISE...EXPECTING LAYERED CLOUDS ABOVE 050. LIGHT SURFACE WINDS OVERNIGHT SHOULD BECOME 170-190 DEGREES AT 8-11 KTS BY LATE MORNING FRIDAY. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...SMF NEAR TERM...SMF SHORT TERM...SMF LONG TERM...CP AVIATION...JAS VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
359 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 358 AM CST FRI NOV 28 2014 TODAY AND TONIGHT...A CHECK ON UPPER LEVEL MOISTURE IN THE NAM...GFS AND RAP MODELS INDICATES AN INCREASE TODAY. UPPER LEVEL WINDS ALSO INCREASE BY 10 TO 15 KT. THIS WOULD SUGGEST THE POTENTIAL FOR CIRRUS DEVELOPING OFF THE LARAMIE RANGE WHICH WOULD SPREAD EAST DURING THE AFTN. THE AMOUNT OF COVERAGE RANGES FROM TOTALLY OVERCAST IN THE GFS TO NEARLY NONE IN THE RAP. THE TEMPERATURE FORECAST USES A MIDDLE OF THE ROAD APPROACH FOR PARTLY CLOUDY CONDITIONS. THE RAP AND NAM ALSO SHOW A WEAK COLD FRONT DROPPING THROUGH NRN NEBRASKA THIS AFTN WHICH WOULD KEEP THE NORTH MOSTLY IN THE 50S FOR HIGHS. SOUTH OF THE FRONT...DESPITE THE HIGH CLOUDS...DEEPER MIXING IS EXPECTED WHICH SHOULD SEND HIGHS INTO THE 60S TO LOWER 70S...NEAR RECORD. TONIGHT...THE MODELS SHOW THE UPPER LEVELS DRYING OUT WHICH WOULD BE ALL FOR CLEARING...LIGHT WINDS AND RADIATIONAL COOLING THE IN THE N/S PLATTE VALLEYS. THE HIGHLANDS STAY MIXED. LOWS TONIGHT RANGE FROM THE LOWER 20S IN THE VALLEYS TO UPPER 30S ACROSS THE SANDHILLS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 358 AM CST FRI NOV 28 2014 FORECAST CONCERNS DEAL WITH TEMPERATURES AND WINDS...AND FIRE WEATHER POTENTIAL FOR SATURDAY. THE NEXT WEEK LOOKS LARGELY DRY ALTHOUGH IT IS POSSIBLE FOR A FEW SNOW SHOWERS /FLURRIES/ WITH LITTLE OR NO ACCUMULATION SATURDAY NIGHT INTO MONDAY MORNING. MODELS HAVE DECENT AGREEMENT THROUGH THE PERIOD NOW SO CONFIDENCE IS IMPROVING WITH THE SENSIBLE WEATHER CONDITIONS FOR THIS FORECAST CYCLE. THE PERIOD BEGINS WITH A VERY ANOMALOUSLY WARM DAY FOR SATURDAY. VERY LITTLE RUN TO RUN CHANGES HAVE BEEN NOTICED ACROSS THE AREA SO GOOD CONFIDENCE ON A VERY WARM DAY. THE IMPENDING STRONG COLD FRONT WILL STAY UP OVER SOUTH DAKOTA THROUGH 00Z SUNDAY WITH THE SURFACE PATTERN SHOWING WESTERLY WINDS ACROSS NEBRASKA. THE WESTERLY COMPONENT OF THE WINDS WILL GIVE THE AIR IN THE BOUNDARY LAYER WARMING DOWNSLOPE CONDITIONS. THE MODELS AREN/T PARTICULARLY STRONG WITH THE WINDS AS THE PRESSURE GRADIENT IS QUITE WEAK BUT DEEPER MIXING INTO THE AFTERNOON SHOULD PROVIDE BREEZY CONDITIONS IN PLACES. THE STRONGER WINDS AT THE TOP OF THE MIXED LAYER ARE ACROSS NORTHERN NEBRASKA AT 20 TO 30KTS. GOING SOUTH...THE SOUTHERN PART OF THE STATE SEES WINDS AT THE SAME LEVEL ONLY AT 10 TO 15KTS. HAVE INCLUDED THE HIGHER WINDS OVER THE NORTHERN AREAS AND LOWER WINDS ACROSS THE SOUTH IN THE FORECAST TODAY. LOOKING INTO HIGHS...MINIMAL CHANGES WERE MADE TO ONGOING FORECAST. THIS LEAVES HIGHS IN THE 60S...WITH LOW 70S OVER THE SOUTHERN PART OF THE STATE. STANDARDIZED ANOMALIES CONTINUE TO SHOW TEMPERATURES AT 850MB AT 2-3 STANDARD DEVIATIONS ABOVE NORMAL. THINKING THIS WILL BE CLOSE TO THE HEIGHT OF THE MIXED LAYER...LIKELY HIGHER OVER THE HIGHER TERRAIN IN THE WESTERN PART OF THE FORECAST AREA SO AGAIN...ONGOING TEMPERATURES LOOK APPROPRIATE WHICH WILL BE NEAR RECORD READINGS. THE OTHER CONCERN WITH SATURDAY WILL BE NEAR CRITICAL FIRE WEATHER POTENTIAL. THE WARM TEMPERATURES AND DRY AIR IN PLACE WILL DROP RELATIVE HUMIDITY DOWN BELOW 20 PERCENT...MAINLY FROM SOUTHWEST NEBRASKA INTO THE EASTERN SANDHILLS. AT THIS TIME...THE STRONGER WINDS DON/T LOOK TO COINCIDE WITH THE DRIER CONDITIONS SO NOT ANTICIPATING THE NEED FOR FIRE WEATHER HEADLINES DESPITE THE WARM AND DRY CONDITIONS. THE COLD FRONT WILL PLOW SOUTH THROUGH THE FORECAST AREA SATURDAY NIGHT. THIS FRONT WILL DROP TEMPERATURES DRAMATICALLY WITH 850MB VALUES LOWERING FROM 13-18C AT 00Z SUNDAY TO -17C TO -10C BY 00Z MONDAY. THIS WILL KEEP THE DIURNAL TEMPERATURE CHANGE VERY MINIMAL ON SUNDAY AND TEMPERATURES WILL ONLY RAISE INTO THE 20S FOR MUCH OF THE AREA. ALSO THINKING WINDS WILL INCREASE BEHIND THE FRONT AND HAVE TRENDED THE FORECAST ACCORDINGLY FOR SATURDAY NIGHT AND SUNDAY. NEARLY UNIDIRECTIONAL WINDS FROM THE NORTH- NORTHWEST...STRONG COLD AIR ADVECTION...GOOD SUBSIDENCE...AND A TIGHT PRESSURE GRADIENT ALL ARE GOOD INGREDIENTS FOR BREEZY TO STRONG WINDS. THE MODELS ARE INDICATING SOME FRONTOGENETICAL FORCING ALONG THE FRONT SATURDAY NIGHT. MOISTURE ISN/T VERY IMPRESSIVE AND REALLY NOT MUCH LIFT IN THE LAYER SO JUST ADDED IN SOME FLURRIES FOR NOW IN AREAS. THEN...ON SUNDAY NIGHT AS THE SURFACE HIGH BUILDS SOUTHEAST INTO EASTER SOUTH DAKOTA RETURN FLOW WILL BE IN PLACE FROM WESTERN KANSAS INTO THE NEBRASKA PANHANDLE. THIS WILL BRING SOME INCREASED MOISTURE INTO LEVELS BELOW 700MB. ALTHOUGH THE MOISTURE DOES INCREASE...THE LIFT IN THE LAYER ISN/T VERY IMPRESSIVE SO DIDN/T HAVE THE CONFIDENCE TO ADD MEASURABLE SNOW IN THE FORECAST YET AND JUST INCLUDED SOME FLURRIES FOR PORTIONS OF THE PANHANDLE SUNDAY NIGHT. MONDAY MORNING WILL BE QUITE COLD AS THE REGION IS INFLUENCED BY THE COLD AIR /850MB TEMPERATURES AT -12C TO -14C AND A SURFACE HIGH CENTERED OVER THE DAKOTAS. THE AIRMASS IN PLACE WOULD SUGGEST LOWS BELOW ZERO ARE CERTAINLY POSSIBLE WHERE WINDS DECOUPLE COMPLETELY AND BECOME CALM. THIS MAY STAY IN AREAS DIRECTLY UNDER THE SURFACE HIGH OVER SOUTH DAKOTA SO KEPT LOWS IN THE SINGLE DIGITS AT THIS TIME THOUGH DID DROP THEM A FEW DEGREES. THE NEXT WORK WEEK LOOKS TO BE A YO-YO IN TEMPERATURES WITH COLD CONDITIONS MONDAY AND WEDNESDAY AND A BIT WARMER FOR TUESDAY AND THURSDAY. THE HIGH DEPARTS MONDAY NIGHT WITH FAIRLY STRONG RETURN FLOW OCCURRING INTO TUESDAY TO PUSH OUT THE COLD AIR MASS WITH A RETURN OF CLOSE TO NEAR NORMAL TEMPERATURES IN THE 40S MOST PLACES. ANOTHER COLD FRONT WILL THEN MOVE THROUGH THE NORTHERN PLAINS AGAIN TUESDAY NIGHT AND MODELS HAVE COME INTO BETTER AGREEMENT IN ITS TIMING AND OTHER DETAILS. THIS FRONTAL PASSAGE LOOKS TO BE DRY AT THIS TIME BUT IT WILL BRING ANOTHER REINFORCING SHOT OF COLDER AIR...ALTHOUGH NOT NEARLY AS COLD AS THE SUNDAY SYSTEM. THEN THURSDAY LOOKS TO BRING STRONG WARM AIR ADVECTION BACK TO PERHAPS GET TEMPERATURES BACK ABOVE NORMAL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1109 PM CST THU NOV 27 2014 PATCHY MIDDLE AND HIGH CLOUD CEILINGS WILL CONTINUE TONIGHT... FRIDAY AND FRIDAY EVENING. WITH LIGHT SOUTHEAST WIND AND LOW LEVEL HUMIDITY APPROACHING 100 PERCENT...PATCHY FOG IS POSSIBLE IN THE RIVER VALLEYS AND OTHER LOW-LYING AREAS. HOWEVER FG/BR WILL BE LOCALIZED. WEST WIND 260-290 WILL INCREASE TO 12-16KT LATE FRIDAY MORNING OR EARLY AFTERNOON. && .FIRE WEATHER... ISSUED AT 317 AM CST FRI NOV 28 2014 TODAY...DEWPOINTS WHERE DERIVED FROM 50 PERCENT OF THE VERY DRY RAP MODEL AND 50 PERCENT OF THE OTHER MODELS. THIS PRODUCES RH VALUES BETWEEN 15 AND 20 PERCENT SOUTH OF INTERSTATE 80. WINDS SHOULD BE LIGHT IN THIS AREA AS THE RAP SHOWS A SFC TROF SETTING UP ACROSS THE SOUTH. SO VERY HIGH FIRE DANGER IS EXPECTED BUT WINDS ARE LIGHT GUSTING TO JUST 20 MPH. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...BROOKS AVIATION...SPRINGER FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
349 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 MODELS HAVE IN GENERAL HANDLED THINGS VERY POORLY LATELY. WHAT WAS GOING TO BE A DECENT SNOW CLIPPERY SYSTEM LAST NIGHT WAS ANYTHING BUT. BAROCLINIC ZONE REMAINED WELL SOUTH AND WEST OF WHAT WAS PROGGED 24 HOURS AGO AND THUS MAIN 1 TO 2 INCH BAND WAS FROM MINOT AREA TO JAMESTOWN TO ALEXANDRIA MN INSTEAD OF BEING FARTHER NORTH. AMOUNTS WEAKER AS WELL AS FOCUS OF WARM ADVECTION AND LIFT SEEMED MORE CONFINED TO ERN SD/WCNTRL MN JUST OUTSIDE OF MAIN PRECIP BAND. ANYHOW FIRST PRECIP BAND OF LIGHT SNOW EASTERN MN INTO WISCONSIN. THERE IS A LARGER AREA OF LIGHT SNOW UPSTREAM IN SASKATCHEWAN INTO SW MANITOBA AND TRYING TO SPREAD INTO NCNTRL ND. LATEST RAP/NAM SEEM OK IN SHOWING THIS LIGHT SNOW SPREADING INTO NRN VALLEY AND PARTS OF NW MN THIS MORNING BEFORE DRYING UP. THERE IS AN AREA OF CONVECTIVE SHOWERS THAT FORMED IN ECNTRL MONTANTA AND IS NOW NORTHWEST OF BISMARCK. RAP HAS SOME PRECIP SURVIVING AND MOVING INTO PARTS OF ECNTRL OR SE ND 12Z-15Z PERIOD. SO WITH CHANCES OF LIGHT SNOW NORTH AND SOUTH KEPT PRETTY BROAD POPS THRU 18Z FRI. TOP DOWN DID SHOW SOME RISK OF SLEET IN FAR SOUTHEASTERN ND IF PRECIP REACHES THAT AREA. THIS AFTN PRETTY QUIET MOST AREAS...THOUGH LINGERING LIGHT SNOW CHANCES FAR NORTH. BUT MAIN 850 MB WARM ADVECTION RETURNS BACK TO CENTRAL SASKATCHEWAN THIS AFTN AHEAD OF SHROT WAVE AND SFC LOW IN SOUTHERN B.C. THIS SYSTEM TO MOVE INTO NORTH CENTRAL ND SATURDAY MORNING WITH MAIN AREA OF WARM ADV SNOWS NORTH OF THE INTL BORDER. THOUGH DID KEEP SOME POPS IN NRN FCST AREA AS SRN EDGE MAY IMPACT AREAS ALONG THE BORDER. QUITE WARM AIR BUILDS INTO THE SOUTHERN HALF OF THE FCST AREA LATER TONIGHT INTO SATURDAY SO HIGHS TODAY WILL BE NEAR LOWS TONIGHT IN MANY AREAS AND THEN RISING TO SOME LOWER OR MID 30S IN THE FAR SOUTH SATURDAY WITH SOUTH WINDS WHILE NORTH WINDS RETURN TO DVL BASIN AND FAR NRN VALLEY AS LOW MOVES EAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 LOW WILL MOVE EAST THRU NRN MN WITH COLD FRONT MOVING SOUTH THRU THE FCST AREA. SOME LIGHT SNOW WITH FRONT BUT NOTHING MUCH. VERY COLD AIRMASS MOVES IN SUNDAY WITH HIGHS LIKELY STAYING BELOW ZERO IN FAR NORTHERN ND. HIGH PRESSURE MOVES IN SUN NIGHT INTO CNTRL ND WITH CLEAR SKY AND DID GO A BIT LOWER THAN SUPERBLEND BASED ON WED NIGHTS LOWS. SUSPECT -20S AGAIN IN THE DVL BASIN. MONDAY TO THURSDAY...OVERALL DRY AND COLD AS THE PERIOD BEGINS WITH SFC HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS AND AN ARCTIC AIRMASS IN PLACE. THE NEXT SHORT WAVE MOVES ACROSS THE INTERNATIONAL BORDER ON MONDAY NIGHT INTO TUESDAY ALLOWING FOR WEAK AND BRIEF RIDGING SCOURING OUT THE WELL BELOW NORMAL COLD AIRMASS. NW FLOW IN THE WAKE OF THIS SHORT WAVE IS NOT AS AMPLIFIED...RESULTING IN A LESS COLD AIRMASS...WITH 850MB TEMPS IN THE 10 TO 18 BELOW RANGE FOR WEDNESDAY. ZONAL FLOW APPEARS TO DEVELOP UP THURSDAY WITH TEMPS REBOUNDING INTO THE 20S. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1148 PM CST THU NOV 27 2014 IFR CONDITIONS WERE LOCATED OVER SOUTHEAST ND AND ADJACENT PARTS OF WEST CENTRAL MN. MVFR CONDITIONS EXTENDS NORTHWEST AND SOUTHEAST OF THE SURROUNDING IFR AREA. VFR CONDITIONS WERE OVER FAR NORTHERN MN. IFR AND MVFR AREA WILL CONTINUE TO SHIFT SOUTHEAST OVERNIGHT. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ SHORT TERM...RIDDLE LONG TERM...JK/RIDDLE AVIATION...HOPPES
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
221 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 221 AM CST FRI NOV 28 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED DEEP...POTENT TROUGHS OVER BRITISH COLUMBIA AND OFF THE COAST OF CALIFORNIA...RIDGING OVER THE WESTERN U.S. AND TROUGHING OVER THE EASTERN U.S.. A SHORTWAVE WAS EVIDENT RIDING THROUGH THE NORTHWEST FLOW FROM NORTHWEST MN INTO WESTERN WI. DPVA FROM THIS SHORTWAVE COMBINED WITH WARM ADVECTION AND PRECIPITABLE WATER NEAR 0.5 INCHES HAS HELPED SUPPORT AN AREA OF SNOW FROM CENTRAL MN INTO THE FORECAST AREA. THE AFOREMENTIONED WARM ADVECTION WAS NICELY EVIDENT AT 850MB FROM 00Z RAOBS WITH READINGS IN THE 8-12C RANGE IN WESTERN SOUTH DAKOTA AND NEBRASKA...COMPARED TO -10 TO -14C OVER THE FORECAST AREA. THIS TIGHT TEMPERATURE GRADIENT WAS ADVECTING EASTWARD BY A 30- 40 KT SOUTHWEST WIND PER VWP/PROFILER DATA. INTERESTINGLY TOO... SURFACE DEWPOINTS OVER WESTERN SOUTH DAKOTA AND NEBRASKA WERE IN THE 20S...ABOUT 10F WARMER THAN CURRENT TEMPERATURES OVER THE FORECAST AREA. GOOD MODEL AGREEMENT EXISTS ON THE 500MB FLOW PATTERN THROUGH THE SHORT TERM PERIOD...SHOWING THE WESTERN U.S. RIDGE FLATTENING OUT AND GETTING PUSHED EASTWARD BY THE POTENT BRITISH COLUMBIA TROUGH DROPPING INTO THE PACIFIC NORTHWEST. THIS PATTERN EVOLUTION RESULTS IN CONTINUOUS WARM AND MOIST AIR ADVECTION FROM SOUTH DAKOTA AND NEBRASKA TOWARDS THE FORECAST AREA. REGARDING THE CURRENT SNOW...REPRESENTED WELL BY 800-700MB FRONTOGENESIS...ANTICIPATING THE EASTWARD PUSH WITH THE UPPER FLOW WILL HELP KEEP THE SNOWBAND MOVING EASTWARD THROUGH THE DAY. THERE COULD BE A SECOND...CALL IT SURGE...OF SNOW AND FRONTOGENESIS DROPPING THROUGH NORTHERN WI LATE THIS MORNING INTO THIS AFTERNOON AS SUGGESTED BY HIGH RESOLUTION MODEL GUIDANCE. THEREFORE...HAVE KEPT THE WINTER WEATHER ADVISORY IN TACT FOR TAYLOR COUNTY. ALSO LATE THIS MORNING THROUGH THE AFTERNOON...WE MAY HAVE TO CONTEND WITH ANOTHER BAND OF PRECIPITATION. THIS BAND CAN CURRENTLY BE SEEN COMING INTO THE WESTERN DAKOTAS ASSOCIATED WITH A SHORTWAVE JUST WEST OF IT...WHICH THE 28.00Z GFS/NAM/HIRES-ARW/NMM AND LATEST RAP/HRRR WANT TO TRAVERSE IT ACROSS LOCATIONS SOUTHWEST OF I-94. THERE COULD BE MID-LEVEL SATURATION ISSUES IN THE WAKE OF THE CURRENT SNOW...BUT MODELS DO WANT TO SATURATE THINGS BACK UP. THEREFORE...HAVE ADDED SOME PRECIPITATION CHANCES. TRACK WISE... REFER THE MORE NORTHERN RAP/HRRR OVER THE FARTHER SOUTH NAM/HIRES- ARW/NMM AS THE FARTHER SOUTH MODELS ARE WAY TOO INTENSE AND TOO FAR SOUTH COMPARED TO CURRENT RADAR IMAGERY. PRECIPITATION TYPE BECOMES AN ISSUE WITH THIS WAVE AS WELL WITH WARMER AIR COMING IN ALOFT. COMPARING MODEL DERIVED REFLECTIVITY OUTPUT WITH THE MAXIMUM TEMPERATURE ALOFT...THE SOUTHWESTERN EDGE MAY POSE A MIX WITH SLEET OR EVEN FREEZING RAIN CONCERN. SINCE THERE IS VERY LOW CONFIDENCE ON ANY SLEET/FREEZING RAIN OCCURRING...HAVE NOT ISSUED ANY WINTER WEATHER ADVISORY FOR THIS WAVE OF PRECIPITATION. AS WE HEAD INTO TONIGHT...CONCERN SHIFTS TO THE CONTINUOUS ADVECTION OF LOW LEVEL MOISTURE. SURFACE DEWPOINTS LATE THIS AFTERNOON COULD BE AS HIGH AS THE MID TO UPPER 30S ALONG I-29 ON THE WESTERN EDGE OF THE SNOWPACK. AS THIS HIGHER MOISTURE TRIES TO ADVECT ACROSS THE SNOWPACK INTO THE FORECAST AREA...WHICH MAY ALREADY HAVE DECENT LOW LEVEL SATURATION FROM THE WAVES OF PRECIPITATION MOVING THROUGH TODAY...ANTICIPATING VERY LOW STRATUS AND FOG TO DEVELOP. WARMER AIR MOVING IN ALOFT NOTED BY 850MB TEMPS CLIMBING TO 6-10C SHOULD ONLY FURTHER STRENGTHEN AN INVERSION...AIDING IN TRAPPING THE LOW LEVEL MOISTURE. HIGHER TERRAIN LOCATIONS SHOULD BE MOST SUSCEPTIBLE TO FOG. LATER SHIFTS MAY NEED TO CONSIDER A DENSE FOG ADVISORY... PARTICULARLY ALONG AND SOUTH OF I-90. WITH THE STRATUS IN PLACE AND IN A GENERAL WARM ADVECTION REGIME...ANTICIPATING VERY LITTLE FALL IN TEMPERATURES TONIGHT FROM AFTERNOON HIGHS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 221 AM CST FRI NOV 28 2014 FOCUS OF ATTENTION FOR THE FIRST PART OF THE LONG TERM PERIOD IS SQUARELY ON THE POTENT TROUGH OVER THE PACIFIC NORTHWEST AT 12Z SATURDAY. MODELS ARE IN GOOD AGREEMENT MARCHING THIS FEATURE EASTWARD THROUGH THE WEEKEND WITH ITS AXIS OVER THE FORECAST AREA BY 12Z MONDAY. PRIOR TO ITS ARRIVAL...925MB TEMPS ARE PROGGED TO CONTINUING WARMING THROUGH THE DAY SATURDAY...CLIMBING TO PERHAPS AS MUCH AS 4-9C. DESPITE STRATUS AND MORNING FOG...THESE READINGS SHOULD ALLOW FOR HIGHS IN THE UPPER 30S TO MID 40S...WITH EVEN A SMALL CHANCE OF HITTING 50 IN VALLEY AREAS AS SUGGESTED BY THE REGIONAL CANADIAN. A SERIES OF TWO COLD FRONTS ARE THEN PROGGED TO MOVE THROUGH THE AREA DURING THE OVERNIGHT HOURS OF SATURDAY NIGHT INTO SUNDAY AS THE TROUGH APPROACHES...RESULTING IN A FALLING TEMPERATURE TREND. 925MB TEMPS PLUMMET TO -14C SOUTH TO -20C NORTH BY 12Z MONDAY. A 25-35KT NORTHWEST WIND AT 925MB SUNDAY INTO SUNDAY NIGHT ALSO ADDS IN A WIND CHILL FACTOR. LOWS SUNDAY NIGHT LOOK TO DROP INTO THE SINGLE DIGITS ABOVE ZERO...A NEAR 40 DEGREE TEMPERATURE DROP FROM SATURDAYS HIGHS. MAY HAVE TO WATCH FOR A POSSIBLE WIND CHILL ADVISORY MONDAY MORNING. PRECIPITATION CHANCES LOOK VERY LOW THROUGH THE WEEKEND DESPITE THE APPROACH OF THE POTENT TROUGH...MOSTLY DUE TO A LACK OF MOISTURE. MONDAY AND MONDAY NIGHT FEATURE CHILLY CONDITIONS AS AN ARCTIC HIGH PRESSURE AREA BUILDS INTO THE REGION FROM THE DAKOTAS. DESPITE ANOTHER SUNNY DAY LIKE YESTERDAY...HIGHS ON MONDAY SHOULD STRUGGLE TO CLIMB INTO THE TEENS. SOME PLACES IN SOUTHEAST MN AND NORTH CENTRAL WI MAY NOT EVEN GET TO 10 ABOVE. THIS SETS THE STAGE FOR TEMPERATURES TO TANK MONDAY EVENING WITH LIGHT WINDS. HOWEVER...THE HIGH DOES MOVE OFF TO THE EAST QUICKLY AFTER MIDNIGHT MONDAY NIGHT...RESULTING IN WARM ADVECTION ACROSS THE FORECAST AREA AND RISING TEMPERATURES. SO...THE BIG QUESTION IS HOW LOW CAN TEMPERATURES DROP PRIOR. THE EC AND CANADIAN SHOW POTENTIAL FOR 10S BELOW ZERO IN SOUTHEAST MN AND NORTH CENTRAL WI...WHEREAS MEX GUIDANCE IS MORE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. SPLIT THE DIFFERENCE FOR NOW FOR LOWS. FOR THE REST OF NEXT WEEK...ANOTHER TROUGH IS PROGGED TO DROP DOWN INTO THE REGION FOR TUESDAY INTO WEDNESDAY. MUCH OF THE COLD AIR WITH THIS TROUGH...AS WELL AS POTENTIAL FOR PRECIPITATION...STAYS TO THE NORTH OF THE FORECAST AREA. IN FACT...THERE SHOULD BE A GOOD REBOUND IN TEMPERATURES FOR TUESDAY AS 925MB TEMPS CLIMB TO -4 TO - 6C. WARM ADVECTION RETURNS FOR WEDNESDAY NIGHT INTO THURSDAY AS THE UPPER FLOW TURNS ZONAL AGAIN...ALLOWING FOR ANOTHER REBOUND FOR TEMPERATURES. HOWEVER...THERE ARE SUGGESTIONS IN THE 28.00Z GFS AND 27.18Z DGEX FOR SOME LIGHT PRECIPITATION TO SPREAD INTO THE REGION AS MOISTURE ALSO RETURNS. THE 28.00Z ECMWF/CANADIAN CONTINUE TO POINT DRY...BUT FOR NOW IN COLLABORATION WITH NEIGHBORING OFFICES HAVE INTRODUCED 20 PERCENT CHANCES FOR THURSDAY FROM A MODEL CONSENSUS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1115 PM CST THU NOV 27 2014 THE BAND OF LIGHT SNOW CONTINUES TO ADVANCE QUICKLY EASTWARD AND STILL LOOKS LIKE IT WILL OVERSPREAD BOTH TAF SITES OVERNIGHT. IT SHOULD MOVE INTO KRST SHORTLY AFTER 06Z AND BASED ON UPSTREAM OBSERVATIONS...IT COULD PRODUCE AN HOUR OR TWO OF IFR CONDITIONS. STILL EXPECTING THE SNOW TO ARRIVE IN KLSE AROUND 09Z AND PRODUCE MVFR CONDITIONS. STILL EXPECTING BOTH SITES TO HAVE ABOUT 3 TO 4 HOURS OF LIGHT SNOW BEFORE THE SHORT WAVE TROUGH AND FRONTOGENESIS IN THE 850-700 MB LAYER MOVE PAST THE REGION. CONDITIONS SHOULD THEN POP BACK UP TO VFR FOR A WHILE EARLY FRIDAY MORNING BEFORE ANOTHER SHORT WAVE TROUGH AND SOME WEAK LOW LEVEL FRONTOGENESIS ARRIVES. NOT EXPECTING THIS TO PRODUCE ANY PRECIPITATION BUT IT SHOULD BE ENOUGH TO BRING THE CEILINGS BACK DOWN TO MVFR WHERE THEY ARE EXPECTED TO REMAIN FOR THE REST OF THE PERIOD. AS WARMER AIR STARTS TO SPREAD IN FRIDAY EVENING...SOME POTENTIAL EXISTS FOR FOG TO DEVELOP WITH THE LOW LEVELS ALREADY SATURATED BELOW THE INVERSION. THE 28.00Z NAM FORECAST SOUNDINGS CONTINUE TO SHOW A LITTLE BIT OF TEMP/DEW POINT SPREAD AT THE SURFACE THROUGH 29.06Z SO HAVE NOT INCLUDE ANY FOG AT THIS TIME. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR WIZ017. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
428 AM MST FRI NOV 28 2014 .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 414 AM MST FRI NOV 28 2014 WLY FLOW ALOFT WILL BE OVER THE RGN THRU TONIGHT. ONCE AGAIN HIGHER LEVEL MOISTURE IS EMBEDDED IN THE FLOW WHICH WILL LEAD TO SOME WAVE CLOUDS. SIMULATED IMAGERY SUGGESTS HI LVL CLOUD COVER THRU THE DAY SO ITS HARD TO SAY HOW MUCH OF AN IMPACT THIS WILL HAVE ON HIGHS. FOR NOW WILL KEEP READINGS IN THE UPPER 60S TO NR 70 AROUND DENVER WITH 60S ACROSS THE PLAINS. IF CLOUD COVER THINS OUT THEN RECORD HIGH OF 72 AT DENVER COULD BE TIED. AREAS ALONG THE PLATTE RIVER VALLEY FM FORT MORGAN TO STERLING MAY STAY IN THE UPPER 50S TO LOWER 60S IF THE HRRR IS CORRECT. AS FOR WINDS MTN TOP INVERSION IS RATHER WK THIS AFTN THRU TONIGHT SO APPEARS THE HIGHEST WINDS WILL STAY ABV TIMBERLINE WITH A FEW GUSTS IN THE 60 TO 70 MPH RANGE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 414 AM MST FRI NOV 28 2014 STRONG WEST-SOUTHWESTERLY FLOW ALOFT WILL COVER THE FORECAST AREA INTO SUNDAY NIGHT. AN UPPER TROUGH WILL MOVE EASTWARD TO OUR NORTH SATURDAY NIGHT INTO MID DAY SUNDAY. UPWARD VERTICAL VELOCITY IS PROGGED FOR THE CWA SATURDAY INTO SUNDAY EVENING. THE BOUNDARY LAYER FLOW IS DOWNSLOPING SOUTHWESTERLIES ON SATURDAY AND SATURDAY NIGHT...WITH A COLD FRONT AND UPSLOPE FOR THE PLAINS AFTER 12Z SUNDAY MORNING. SOME FORM OF EASTERLY COMPONENT IS PROGGED THROUGH SUNDAY NIGHT FOR THE PLAINS AND FOOTHILLS. THE HIGHEST WINDS IN THE MOUNTAINS LOOK TO COME SATURDAY NIGHT...THE WAVE SET UP LOOKS THE STRONGEST THAN. NO HIGHLIGHTS. FOR MOISTURE...IT IS SPARSE SATURDAY AND SATURDAY NIGHT. THERE IS AN INCREASE FOR THE WESTERN CWA ON SUNDAY...BUT NOT A LOT IN THE LOWER LEVELS. THERE IS SOME LOW LEVEL MOISTURE OVER THE EASTERN HALF OF THE PLAINS WITH THE UPSLOPE BY SUNDAY AFTERNOON AND EVENING. MOISTURE IS BEST SUNDAY NIGHT...FAIRLY DEEP IN THE MOUNTAINS. MODELS SHOW A TAD OF MEASURABLE SNOWFALL ON THE QPF FIELDS FOR THE MOUNTAINS AND THE NORTHERN BORDER AREAS LATE SUNDAY AFTERNOON INTO EARLY MONDAY MORNING. WILL GO WITH SOME MINOR POPS IN THE MOUNTAINS SUNDAY NIGHT...THAT`S IT. SATURDAY`S HIGH TEMPERATURES ARE 1-2 C COOLER THAN THIS AFTERNOON`S HIGHS. ON SUNDAY...READINGS COOL DOWN SOME 10-20 C FROM WEST TO EAST. FOR THE LATER DAY`S...MONDAY THROUGH THURSDAY...THE ECMWF AND THE GFS HAVE COME MORE IN LINE WITH ONE ANOTHER. THERE IS ZONAL TO WEST-NORTHWESTERLY FLOW ALOFT ON MONDAY...THEN SOME UPPER RIDGING TUESDAY INTO WEDNESDAY...WITH THE ECMWF HAVING WEAK UPPER RIDGING ON WEDNESDAY. ON THURSDAY... THEY BOTH HAVE WEAK UPPER RIDGING. OVERALL THEY AGREE A BIT BETTER THAN YESTERDAY`S 00Z RUNS. THE GFS HAS MORE MOISTURE. WILL HAVE SOME MINOR ALPINE POPS HERE AND THERE BUT NOTHING SIGNIFICANT. && .AVIATION...(FOR THE TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 414 AM MST FRI NOV 28 2014 OUTSIDE OF SOME UPPER LVL CLOUD COVER VFR CONDITIONS WILL CONTINUE TODAY AND TONIGHT. AS FOR WINDS THEY HAVE BEEN RANGING FM SLY TO WLY THE LAST FEW HOURS SO WILL KEEP THEM SSW THRU THE MORNING HOURS. BY EARLY AFTN THE RAP AND HRR INDICATE THEY MAY BRIEFLY BECOME WLY FOR A FEW HOURS BEFORE TRENDING BACK TO MORE SSW BY LATE AFTN. FOR TONIGHT WINDS SHOULD BE DRAINAGE. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...RPK LONG TERM...RJK AVIATION...RPK
AREA FORECAST DISCUSSION
NWS ALBANY NY
631 AM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE REGION ACCOMPANIED BY BELOW NORMAL TEMPERATURES INTO THE FIRST HALF OF THE WEEKEND. A WARM FRONT WILL BRING SOME SCATTERED RAIN AND SNOW SHOWERS SATURDAY NIGHT INTO SUNDAY WITH MILDER WEATHER TO CLOSE OUT THE HOLIDAY WEEKEND. && .NEAR TERM /THROUGH TONIGHT/... AS OF 615 AM EST...LIGHT SNOW/FLURRIES WERE DIMINISHING AS THE AXIS OF THE UPPER TROUGH WAS JUST ABOUT OVERHEAD. HOWEVER...LAKE EFFECT ACTIVITY WAS EVOLVING DOWNWIND OF LAKE ONTARIO EXTENDING ALONG THE I81 CORRIDOR. PER THE HRRR AND EXPERIMENTAL HRRRX REFLECTIVITY FORECASTS...THIS BAND WILL LIFT NORTHWARD TOWARD 15Z INTO PORTIONS OF HERKIMER COUNTY AS LOW LEVEL FLOW BACKS WITH HIGH PRESSURE ATTEMPTING TO BUILD IN FROM THE WEST. OTHERWISE...WHILE SOME BREAKS OF SUNSHINE ARE EXPECTED THIS MORNING /MAINLY SOUTH OF ALBANY/...MORE CLOUDS ARE EXPECTED. UPDATE TO HOURLY TEMPS/DEWPOINTS/SKY FORECAST AND TWEAKS TO THE POP/WX BASED ON THE AFOREMENTIONED REFLECTIVITY FORECASTS. PREV DISC... UPPER LEVEL TROUGH AXIS CONTINUES TO SLOWLY TRACK ACROSS THE STATE. REGIONAL AND LOCAL RADAR REVEAL VERY LIGHT RETURNS OF THE LIGHT SNOW/SNOW SHOWERS MAINLY ALONG AND EAST OF THE HUDSON RIVER. EXTRAPOLATION OF THE UPPER TROUGH FORWARD MOVEMENT...THE AXIS OF THIS FEATURE WILL BE ACROSS THE HUDSON RIVER VALLEY AOA 12Z. THIS SHOULD ELIMINATE THE LIGHT SNOW/SNOW SHOWERS FROM WEST TO EAST THROUGH THIS EARLY MORNING HOURS. HOWEVER...AS BOUNDARY LAYER AND MEAN FLOW BECOME WESTERLY ALONG WITH COLD ADVECTION /H850 TEMPS DROP BACK TOWARD -15C/...LAKE EFFECT SNOW WILL ONCE AGAIN DEVELOP DOWNWIND OF LAKE ONTARIO. MEANWHILE...SURFACE RIDGE AXIS WILL BE BUILDING INTO UPSTATE NEW YORK THROUGH THE DAY. PER THE BUFR SOUNDINGS...FAVORABLE INVERSION LEVEL HEIGHTS AND MOIST LOW LEVELS WILL ALLOW LAKE BANDS TO TRACK INLAND THROUGH THE DAY. THAT RIDGE THOUGH WILL LIMIT THE INLAND EXTENT SOMEWHAT SO WE WILL CONTINUE TO CONFINE THE POPS MAINLY INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN DACKS. AS FOR THOSE CRUCIAL LOW LEVEL WIND TRAJECTORIES...THE FLOW WILL GENERALLY BE BETWEEN 280-310 PER THE LATEST RAP13/HRRR. DUE TO THE COLDER TEMPS ALOFT AND FRESH SNOW COVER ACROSS MOST OF REGION...TEMPERATURES TODAY WILL AVERAGE A GOOD 10 DEGREES BELOW NORMAL. TONIGHT...THE AFOREMENTIONED RIDGE AXIS WILL SLIDE ACROSS THE REGION. THIS WILL SHUT DOWN THE LAKE EFFECT INLAND EXTENT THROUGH THE EARLY EVENING HOURS. THEREAFTER...A WARM FRONT WILL BE APPROACHING DURING THE OVERNIGHT HOURS. THIS TOO WILL BRING ADDITIONAL CLOUD COVER ALONG WITH THE SLIGHT CHANCE FOR LIGHT SNOW TO DEVELOP ACROSS THE WESTERN PORTIONS OF THE CWFA. SO WHERE CLOUDS DO BREAK UP...TEMPERATURES SHOULD QUICKLY FALL BACK INTO THE TEENS BEFORE STEADYING OFF WITH THE CLOUD COVER INCREASING. && .SHORT TERM /SATURDAY THROUGH SUNDAY/... THE REMAINDER OF THE HOLIDAY WEEKEND WILL FEATURE A PASSAGE OF A WARM FRONT AND LIKELY HIGHER LEVELS OF LOW LEVEL MOISTURE. MODEL QPFS ARE RATHER LIGHT BUT DO INDICATE THE POTENTIAL FOR EITHER SOME VERY LIGHT SNOW/FLURRIES AND/OR LIGHT RAIN/DRIZZLE DEPENDING ON THERMAL PROFILES. ISENTROPIC ANALYSIS DEPICTS THE BEST LIFT AND LOW CPD/S WILL BE ACROSS THE DACKS REGION INTO THE ST LAWRENCE VALLEY. SO WE WILL GO WITH SLIGHT CHANCE TO CHANCE POPS ALONG WITH A MAINLY CLOUDY SKY THROUGH THE WEEKEND. AS FOR TEMPERATURES...DUE TO THE CLOUD COVER EXPECTED ALONG WITH THE WARMING THERMAL COLUMN...WE WILL FAVOR THE COOLER SIDE OF THE GUIDANCE ENVELOPE. HIGHS MAINLY INTO THE 30S ON SATURDAY THEN INTO THE LOWER HALF OF THE 40S ON SUNDAY. WE WILL FOLLOW A NON-DIURNAL TEMPERATURE TREND SATURDAY NIGHT WITH LOWS LIKELY ATTAINED IN THE EVENING WITH SLOWLY RISING TEMPS OVERNIGHT. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... AT THE START OF THE EXTENDED PERIOD...A FRONTAL BOUNDARY WILL BE APPROACHING THE REGION FOR SUNDAY NIGHT INTO MONDAY. WITH A SOUTHERLY FLOW AHEAD OF THIS BOUNDARY...TEMPS WILL BE RELATIVELY MILD FOR SUN NIGHT...WITH MANY LOCATIONS ABOVE FREEZING IN THE MID TO UPPER 30S. THIS FRONT WON/T HAVE A LOT OF MOISTURE ASSOCIATED WITH IT...BUT WILL ALLOW SLIGHT TO LOW CHC POPS FOR RAIN OR SNOW SHOWERS. THE MODELS ARE UNCLEAR IN THE EXACT TIMING OF THE BOUNDARY. IF IT WAITS UNTIL LATER ON MONDAY TO PASS THROUGH...TEMPS MAY WIND UP BEING MILD FOR MONDAY WITH MID TO UPPER 40S FOR VALLEY AREAS /UPPER 30S TO LOW 40S FOR HIGH TERRAIN LOCATIONS/. BEHIND THIS FRONTAL SYSTEM...HIGH PRESSURE WILL BUILD INTO THE AREA FOR MONDAY NIGHT INTO TUESDAY. THIS WILL END THE THREAT FOR ANY PRECIP AND ALLOWS CLEARING SKIES AND COLDER TEMPS. WITH A COLD CANADIAN AIR MASS MOVING INTO THE REGION...OVERNIGHT LOWS LOOK LIKE THEY MAY WIND UP DROPPING DOWN INTO THE TEENS TO LOW 20 FOR MON NIGHT. HIGHS ON TUESDAY WILL BE NOTICEABLY COLDER...WITH MANY LOCATIONS REMAINING BELOW FREEZING FOR MOST OF THE DAY...WITH HIGHS IN THE MID 20S TO MID 30S. WITHIN THE FAST ZONAL FLOW...ANOTHER STORM SYSTEM WILL RAPIDLY BE APPROACHING THE REGION FOR TUESDAY NIGHT INTO WEDNESDAY. ALTHOUGH SOME PRECIP MAY START AS LIGHT SNOW SHOWERS...PRECIP LOOKS TO CHANGE TO RAIN FOR WEDNESDAY AS WARMER AIR MOVES INTO THE REGION. THERE MAY EVEN BE A PERIOD OF SLEET OR FREEZING RAIN WITH THE TRANSITION...BUT WILL NOT PUT IT IN THE GRIDS QUITE YET...AS THERE IS A GREAT DEAL OF UNCERTAINTY REGARDING THE TIMING/EXTENT OF THIS. ANY PRECIP LOOKS FAIRLY LIGHT...WITH LIMITED MOISTURE PREVENTING MUCH QPF IN GENERAL. ANY PRECIP LOOKS TO END BY WEDNESDAY NIGHT. MINS TUESDAY EVENING WILL BE IN THE 20S...WITH TEMPS RISING TO THE MID 30S TO LOW 40S FOR WEDNESDAY. MINS WED NIGHT WILL BE IN THE MID 20S TO LOW 30S. ANOTHER BRIEF AREA OF HIGH PRESSURE LOOKS TO BUILD INTO THE REGION FOR THURSDAY WILL QUIET AND DRY WEATHER. HIGHS WILL BE SEASONABLE...WITH MID 30S TO LOW 40S FOR VALLEY AREAS. ANY DRY WEATHER WILL BE BRIEF...AS YET ANOTHER STORM WITH LIGHT PRECIP WILL BE APPROACHING FOR THE LATE WEEK PERIOD. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... FLYING CONDITIONS ARE CURRENTLY VFR FOR THE HUDSON VALLEY TAF SITES WITH JUST SOME PATCHES OF MID LEVEL CLOUDINESS...ALTHOUGH MVFR CIGS CONTINUE AT KPSF DUE TO LOW CLOUDS THAT REMAINED IN PLACE ACROSS THE HIGH TERRAIN OVERNIGHT. THESE CLOUDS LOOK TO DISSIPATE WITHIN THE NEXT HOUR OR SO...ALLOWING FOR VFR CONDITIONS TO RETURN THERE. DURING THE DAY TODAY...THE COOL TEMPS ALOFT ASSOCIATED AN UPPER LEVEL TROUGH WILL CAUSE SOME DIURNAL CU/STRATOCU TO DEVELOP. NO PRECIP IS EXPECTED...AS LIMITED MOISTURE/FORCING WILL PREVENT ANY SNOW SHOWERS OR FLURRIES FROM DEVELOPING...AND ANY LAKE EFFECT ACTIVITY WILL REMAIN WELL TO THE WEST. STILL...CIGS WILL BE BKN AROUND 3500-5000 FT...BUT FLYING CONDITIONS SHOULD REMAIN VFR. DURING DAYTIME MIXING...WEST TO NORTHWEST WINDS WILL INCREASE TO AROUND 10 KTS WITH A FEW HIGHER GUSTS...MAINLY FOR KALB/KPSF. WITH A WARM FRONT STARTING TO APPROACH...SOME CLOUDS WILL CONTINUE INTO TONIGHT...BUT NO PRECIP IS EXPECTED. OUTLOOK... SATURDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA...SHSN. SUNDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING TUESDAY. ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN AVERAGES AT A TENTH OF AN INCH OR LESS THE NEXT FEW DAYS. SNOWFALL ACCUMULATIONS WILL BE A COATING TO A FEW INCHES IN A FEW SPOTS THROUGH TODAY...A LITTLE HIGHER DOWNWIND OF LAKE ONTARIO INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS. MILDER TEMPS ARE EXPECTED SUNDAY WITH SOME SNOW MELT. HOWEVER... TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH THE PASSAGE OF A STRONG COLD FRONT. 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. && .CLIMATE... A RECORD SNOWFALL OF 9.6 INCHES WAS SET AT ALBANY NY WEDNESDAY. THIS BREAKS THE OLD RECORD OF 4.9 SET IN 1888. ALSO...THIS PLACES THE STORM INTO THE NUMBER 5 SLOT OF THE TOP 10 SNOWSTORMS FOR NOVEMBER FOR ALBANY. WITH ADDITIONAL SNOWFALL EXPECTED THIS WEEKEND...WE WILL ALSO WATCH HOW MUCH ADDS UP TO SEE WHERE WE FINISH UP FOR SNOW BY THE END OF THIS MONTH. THE 10.4 INCHES OF SNOW AT THE ALBANY INTERNATIONAL AIRPORT PLACES THE SNOWSTORM AS NUMBER 5 ALL-TIME FOR THE MONTH OF NOVEMBER. TOP 5 NOVEMBER STORMS AT ALBANY 1884-2014 AMOUNT DATE YEAR 1. 22.5 INCHES 24-25 1971 2. 17.3 INCHES 14-15 1972 3. 14.1 INCHES 22-23 1943 4. 11.8 INCHES 17-18 1980 5. 10.4 INCHES 26-27 2014 && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...NONE. MA...NONE. VT...NONE. && $$ SYNOPSIS...BGM NEAR TERM...BGM SHORT TERM...BGM/WASULA LONG TERM...FRUGIS AVIATION...FRUGIS HYDROLOGY...BGM/WASULA CLIMATE...NWS ALBANY FOR THE LATEST UPDATES...PLEASE VISIT OUR WEBPAGE AT WWW.WEATHER.GOV/ALBANY
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
912 AM EST FRI NOV 28 2014 .DISCUSSION... ...HAZARDOUS BOATING CONDITIONS INTO TONIGHT... ADVECTION OF COLDER AIR SWD INTO THE AREA REMAINS ONGOING PAST SUNRISE AND INTERESTINGLY WAS NOT TIMED TO COINCIDE WHOLLY WITH THE NIGHT TIME PERIOD. WITH THE LOW SUN ANGLE TEMPS WILL STRUGGLE TO RISE TO FORECAST HIGHS THIS AFTERNOON. RECENT EDITS HAVE LOWERED TEMPS WHILE REMAINING IN THE 50S NORTH OF I4 AND LOWER TO MID 60S OVER THE REMAINDER OF THE AREA. A LITTLE VEERING TO SFC TO BL WINDS IS FORECAST BY RUC WITH A NNE COMPONENT TOWARD LATE AFTN. MARINE BASED CLOUDINESS LOOKS TO BE AN OPEN CELL SC NEARSHORE AND SOME SCT SC WL AFFECT THE COASTAL COUNTIES AND BEACHES FROM ALONG WITH WIND GUSTS NR 20 MPH. && .AVIATION...VFR THROUGH TONIGHT. A SMALL CHANCE CEILINGS AT OR ABOVE FL035 EXISTS AT COASTAL SITES...GENERALLY ALONG THE IMMEDIATE CST FM KVRB-KSUA THIS AFTERNOON/EVENING. && .MARINE... LTST BUOY/COASTAL OBS INDICATE GUSTY NORTH WINDS 20-25 KNOTS IN THE OPEN ATLANTIC. ADDITIONALLY...COUNTERING WINDS WL CREATE CHOP IN/NEAR THE GULFSTREAM. SPEEDS MAY EASE A LITTLE BY AFTERNOON ESPECIALLY ALONG THE NORTH COAST...BUT IT WILL STILL NOT BE GOOD FOR SMALL CRAFT OPERATION. HIGH PRESSURE RIDGE WILL BUILD TO THE GEORGIA/CAROLINA COAST TONIGHT AND GRADUALLY EASE WINDS MORE...BUT ADVISORY CONDITIONS SHOULD CONTINUE IN THE GULF STREAM AT LEAST THROUGH THE LATE EVENING HOURS. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...NONE. AM...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 AM EST SATURDAY FOR COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ JP/DKW
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
617 AM EST FRI NOV 28 2014 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 332 AM EST FRI NOV 28 2014 HIGH PRESSURE WILL REMAIN IN CONTROL OVER THE AREA THROUGH TONIGHT. THIS WILL RESULT IN DRY BUT COLD WEATHER FOR INDIANA. THE HIGH WILL BEGIN TO DRIFT EAST OF INDIANA LATER TODAY. THIS WILL ALLOW WARMER SOUTHERLY FLOW TO RETURN TO CENTRAL INDIANA IN ADDITION TO CHANCES FOR SHOWERS AS FIRST A WARM FRONT LIFTS NORTH OVER THE AREA...FOLLOWED BY A COLD FRONT SUNDAY NIGHT. DRY AND COLD WEATHER WILL RETURN TO THE AREA BEHIND THE FRONT ON MONDAY NIGHT. THEN SLOWLY THROUGH MID WEEK TEMPERATURES WILL WARM BACK TO NORMAL VALUES FOR THIS TIME OF YEAR. NEXT CHANCE FOR PRECIPITATION WILL BE THURSDAY AND FRIDAY AS A SYSTEM FROM THE PLAINS MOVES INTO THE AREA. && .NEAR TERM /TODAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 SHORT TERM GUIDANCE DID NOT HAVE A VERY GOOD HANDLE ON THE FLURRIES/BORDERLINE LIGHT SNOW SHOWERS WHICH OCCURRED OVER CENTRAL INDIANA FOR MOST OF THANKSGIVING DAY AND NIGHT...AND HAVE SINCE EXITED THE REGION. KNOWING THIS...AND SEEING THE HRRR AND SREF DEVELOPING LIGHT PRECIP RETURNS MOVING INTO CENTRAL INDIANA FROM ILLINOIS EARLY THIS MORNING...SERIOUSLY CONSIDERED PUTTING IN AT LEAST A MENTION OF FLURRIES. AS IS CUSTOMARY WITH THESE TYPE OF LIGHT WINTRY PRECIP SITUATIONS THE REST OF THE SHORT TERM GUIDANCE IS SHOWING NOTHING BUT COMPLETELY DRY AND PARTLY CLOUDY SKY CONDITIONS TODAY. BASED ON TRENDS UPSTREAM...IT DOES NOT APPEAR THESE RETURNS ARE MAKING IT TO THE SURFACE SO WILL REFRAIN FROM EVEN PUTTING FLURRIES IN THE FORECAST AT THIS TIME. HOWEVER WILL NEED TO PAY CLOSE ATTENTION THROUGH EARLY THIS MORNING TO SEE IF FLURRIES OR EVEN -SN NEEDS TO BE INCLUDED IN THE FORECAST. OTHERWISE...AFTER THIS MORNING/S POTENTIAL FOR FLURRIES...THE REST OF TODAY LOOKS FAIRLY BENIGN AS SURFACE HIGH PRESSURE BEGINS TO SHIFT EAST OF THE REGION. SKIES PARTLY CLOUDY ACROSS THE SOUTH TO MOSTLY CLOUDY FOR FAR NORTHERN COUNTIES AS THIS AREA IS CLOSER TO AN UPPER WAVE THAT WILL BE MOVING THROUGH THE GREAT LAKES. BLEND OF GUIDANCE SEEMS REASONABLE FOR HIGHS 33 (NORTHEAST) TO LOW 40S (SOUTHWEST CWA). && .SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/... ISSUED AT 332 AM EST FRI NOV 28 2014 TONIGHT DRY AND COLD CONDITIONS WILL PREVAIL. ONLY DIFFERENCE IS THE LOWS WILL ACTUALLY BE CLOSER TO NORMAL THANKS TO THE CHANGE TO SOUTHERLY LOW LEVEL FLOW ON THE BACKSIDE OF THE HIGH PRESSURE. TEMPERATURES WILL JUST KEEP ON CLIMBING RIGHT THROUGH THIS WEEKEND AS STRONG WARM AIR CONTINUES TO ADVECT INTO THE REGION AS A SURFACE WARM FRONT LIFTS NORTH OVER THE AREA ON SATURDAY. MODELS HAVE BEEN HINTING AT SOME WEAK CHANCE FOR SHOWERS ASSOCIATED WITH THIS FEATURE AND SEEM TO BE IN AGREEMENT WITH AT LEAST SOME VERY LIGHT PRECIP POSSIBLE BEGINNING SATURDAY AFTERNOON AND CONTINUING THROUGH THE WEEKEND WITH VERY WEAK CHANCES UNTIL A COLD FRONT MOVES THROUGH ON SUNDAY NIGHT. THIS LATTER PORTION OF THE WEEKEND APPEARS TO HAVE THE BEST CHANCES FOR PRECIP CONSIDERING THE FORCING WITH THE FRONT AND HIGHER PWATS AND MOISTURE. FELT CONFIDENT ENOUGH TO INCREASE POPS TO AT LEAST WIDESPREAD CHANCE WITH EVEN LIKELY POPS ACROSS THE SOUTHEASTERN PORTION OF THE CWA SUNDAY NIGHT. AS FOR TEMPERATURE OVER THE WEEKEND LEANED TOWARD THE WARMER MAV GUIDANCE AND EVEN BUMPED UP HIGHS A DEGREE OR TWO BASED ON VERY STRONG WARM AIR ADVECTION. AND ACTUALLY INCREASED LOWS SLIGHTLY FOR SAME REASON...AND ALSO FACTORED IN CHANCES FOR PRECIP AND CLOUDY SKIES...ESPECIALLY FOR THE LATTER HALF OF THE WEEKEND. HIGHS SAT UPPER 40S TO MID 50S...FOR SUNDAY UPPER 50S TO LOW 60S. VERY IMPRESSIVE CONSIDERING NORMAL HIGHS ARE MID 40S. && .LONG TERM /MONDAY THROUGH THURSDAY/... ISSUED AT 332 AM EST FRI NOV 28 2014 A FRONT SOUTH OF INDIANA AND AN UPPER WAVE MOVING THROUGH WILL KEEP CHANCES FOR A MIX OF RAIN AND SNOW IN THE FORECAST FOR MONDAY...BUT THESE CHANCES WILL DECREASE AS THE FRONT SINKS SOUTH AND THE WAVE MOVES OFF TO THE EAST. DRY WEATHER IS THEN EXPECTED MONDAY NIGHT THROUGH WEDNESDAY NIGHT WITH HIGH PRESSURE MOVING ACROSS THE AREA. TEMPERATURES WILL REMAIN BELOW NORMAL DURING THIS TIME. MODELS ARE SHOWING SOME VARIABILITY FROM WEDNESDAY ON AND WITH A FAIRLY PROGRESSIVE PATTERN THERE IS LITTLE TO KEY IN ON SO WILL JUST ACCEPT INITIALIZATION...YIELDING SMALL CHANCES FOR RAIN THURSDAY WITH A WARM UP. && .AVIATION /DISCUSSION FOR 281200Z TAF ISSUANCE/... ISSUED AT 615 AM EST FRI NOV 28 2014 EXPECTING MOSTLY VFR THROUGH THE PERIOD. WINDS WILL INCREASE AND TURN OUT OF THE SOUTH TODAY WITH GUSTS AROUND 20 KTS OR SO THIS AFTERNOON AT ALL SITES BUT KBMG. SHOULD SEE MAINLY MID LEVEL CEILINGS TODAY WITH SOME POTENTIAL FOR MVFR TO DEVELOP NEAR THE END OF THE TAF PERIOD AS THE NEXT WAVE APPROACHES. LOOKING AT UPSTREAM OBSERVATIONS MAY INCLUDE A TEMPO GROUP FOR MVFR CONDITIONS WITH LIGHT SNOW AT KLAF BUT WILL LEAVE THIS OUT ELSEWHERE AS IT COULD STAY NORTH OF THE OTHER SITES. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...SMF NEAR TERM...SMF SHORT TERM...SMF LONG TERM...CP AVIATION...CP VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
459 AM CST FRI NOV 28 2014 .UPDATED FOR 12Z AVIATION DISCUSSION... ISSUED AT 447 AM CST FRI NOV 28 2014 && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CST FRI NOV 28 2014 MAIN CONCERN IN THE SHORT TERM IS THE POTENTIAL FOR FREEZING RAIN OR SLEET LATER TODAY AS A WEAK DISTURBANCE MOVES ALONG THE MINNESOTA RIVER VALLEY. MEANWHILE TEMPERATURES WILL MODERATE INTO THE 20S TODAY...AND REMAIN THEIR OVERNIGHT. A BAND OF LIGHT TO MODERATE SNOW TIED TO THE H850-H700 WARM AIR ADVECTION MOVED ACROSS THE NORTHERN HALF OF THE FORECAST AREA OVERNIGHT AND PRODUCED ROUGHLY 1 TO 2 INCHES OF SNOW. BY EARLY FRIDAY MORNING THIS BAND WAS LOCATED ACROSS EASTERN MN WESTERN WI...AND AS A RESULT DROPPED THE UPSTREAM COUNTIES FROM THE WINTER WEATHER ADVISORY. LATER TODAY ANOTHER WEAK SHORTWAVE WILL SLIDE ACROSS THE REGION. THIS SEEMS TO BE HANDLED BEST BY THE LAST FEW RUNS OF THE RAP13. THE CONCERN WITH THIS FEATURE IS THE POTENTIAL FOR PRECIP FALLING THROUGH A WARM LAYER WHICH BY 18Z IS FORECAST TO BE +3C AT KMSP AND EVEN WARMER AT POINTS SOUTHWARD. THE SURFACE WILL STILL BE IN THE 20S...SO THIS WOULD LEAD TO A BRIEF PERIOD OF SLEET/FREEZING RAIN ROUGHLY ALONG A LINE JUST SOUTH OF THE I-94 CORRIDOR...REACHING EAU CLAIRE BY LATE AFTERNOON. ACCUMULATIONS WOULD ONLY BE 1 OR 2 HUNDREDTHS...BUT EVEN THOSE MEAGER AMOUNTS COULD LEAD TO SLICK ROADWAYS. FOR NOW INCREASED THE POPS AND TRENDED TOWARDS THE LAST FEW RUNS OF THE HOPWRF AND HRRR WHICH HAVE SLOWED THE ONSET OF THIS PRECIP. ONCE THIS MOVES THROUGH H850 AIR OF +5 TO +7 WILL REMAIN IN PLACE OVERNIGHT...AS SOUTHEASTERLY WINDS GRADUALLY VEER TO A SOUTHERLY DIRECTION BY SATURDAY MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 357 AM CST FRI NOV 28 2014 STRONG WARM AIR ADVECTION WILL BE THE PREVAILING STORY SATURDAY WITH A WMFNT WELL N OF THE WFO MPX CWFA AND AN INCOMING ARCTIC HIGH PRES AIRMASS THAT LOOKS TO DROP THE HAMMER ON TEMPERATURES GOING INTO SUNDAY. NOT LOOKING FOR MUCH OF ANYTHING IN TERMS OF PRECIPITATION SO SATURDAY WILL RESULT IN MOSTLY CLOUDY SKIES DUE TO INCREASED MOISTURE PROMOTING STRATUS DEVELOPMENT OVER A DECENT SNOWPACK AND FAIRLY WIDESPREAD NVA KEEPING PRECIP N OF THE AREA. DESPITE THE CLOUD COVER...THE STRONG WAA WILL FORCE HIGHS INTO THE UPR 30S AND EVEN LWR 40S. BY LATE EVENING...A POTENT CDFNT WILL DROP THRU THE CWFA...WHICH WILL HELP SCOUR OUT SOME OF THE CLOUD COVER BUT IS NOT XPCTD TO PRODUCE MUCH...IF ANY...PRECIP FOR THE CWFA. WINDS WILL KICK UP BUT THE MAIN EFFECT WILL BE TO SIGNIFICANTLY DROP TEMPERATURES FOR SUNDAY...WITH HIGHS ONLY REACHING THE LWR TEENS TO LWR 20S. THE ARCTIC HIGH PRES AIRMASS WILL PERSIST THRU MON...PRODUCING HIGHS ONLY IN THE SINGLE DIGITS ABOVE ZERO DESPITE PLENTY OF SUNSHINE. AS THE HIGH PRES AREA SHIFTS OFF TO THE E FOR THE MIDDLE PORTION OF NEXT WEEK...A MORE SOUTHERLY FLOW ON THE BACKSIDE WILL ALLOW SOME MODERATION IN TEMPERATURES BUT STILL BELOW THE FREEZING MARK. HIGHS WILL CLIMB INTO THE 20S...WITH VERY LITTLE CHANCES OF PRECIP GOING THROUGH THE WEEK. THERE ARE STILL SOME INDICATIONS OF A MORE ORGANIZED LOW PRES SYSTEM MOVING THRU THE CENTRAL CONUS MID-TO-LATE NEXT WEEK BUT MODEL CONSENSUS...AND HENCE FORECAST CONFIDENCE...REMAINS LOW IN THIS THINKING SO HAVE KEPT MUCH OF THE AREA DRY THRU NEXT WEEK. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 447 AM CST FRI NOV 28 2014 SUBSTANTIAL CHANGES TO THE TAFS. THE MODELS SEEM TO BE OVERDOING THE MOISTURE...AND THUS HAVE ELIMINATED THE PERSISTENT MVFR STRATUS THAT WAS PREVIOUSLY IN PLACE. THE LATEST OBS...LAMP GUIDANCE...AND HOPWRF CLOUD PROBABILITIES SUPPORT THIS. CHANCES REMAIN FOR AN AREA OF SLEET/FREEZING RAIN ACROSS CENTRAL MN/WI CENTERED AROUND 18Z. LATE TONIGHT SOME SLEET IS POSSIBLE ACROSS NORTHERN MN...INCLUDING KAXN AND KSTC. FORECAST SOUNDINGS SHOW POTENTIAL FOR MVFR/IFR STRATUS RETURNING...BUT THIS LOW LEVEL MOISTURE SEEMS OVERDONE. KMSP... THE LAST FEW RUNS OF THE HOPWRF/HRRR HAVE DELAYED THE MIXED PRECIP UNTIL AFTER 18Z THIS AFTERNOON. IT STILL APPEARS SOME LIGHT FZDZ/PL ARE POSSIBLE...BUT ACCUMULATIONS WILL BE NO MORE THAN 1-2 HUNDREDTHS. WENT OPTIMISTIC WITH CLOUDS FOR THE REST OF THE DAY...FOR REASONS DESCRIBED IN THE GENERAL DISCUSSION. /OUTLOOK FOR KMSP/ SUN...VFR. WINDS NW AT 15G25KTS. MON...VFR. WINDS NW AT 5-10KTS...BECOMING S LATE. TUE...VFR. WINDS S AT 15G20KTS...BECOMING W. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR MNZ045- 052-053. WI...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR WIZ014>016. && $$ SHORT TERM...JRB LONG TERM...JPC AVIATION...JRB
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
434 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CST FRI NOV 28 2014 MAIN CONCERN IN THE SHORT TERM IS THE POTENTIAL FOR FREEZING RAIN OR SLEET LATER TODAY AS A WEAK DISTURBANCE MOVES ALONG THE MINNESOTA RIVER VALLEY. MEANWHILE TEMPERATURES WILL MODERATE INTO THE 20S TODAY...AND REMAIN THEIR OVERNIGHT. A BAND OF LIGHT TO MODERATE SNOW TIED TO THE H850-H700 WARM AIR ADVECTION MOVED ACROSS THE NORTHERN HALF OF THE FORECAST AREA OVERNIGHT AND PRODUCED ROUGHLY 1 TO 2 INCHES OF SNOW. BY EARLY FRIDAY MORNING THIS BAND WAS LOCATED ACROSS EASTERN MN WESTERN WI...AND AS A RESULT DROPPED THE UPSTREAM COUNTIES FROM THE WINTER WEATHER ADVISORY. LATER TODAY ANOTHER WEAK SHORTWAVE WILL SLIDE ACROSS THE REGION. THIS SEEMS TO BE HANDLED BEST BY THE LAST FEW RUNS OF THE RAP13. THE CONCERN WITH THIS FEATURE IS THE POTENTIAL FOR PRECIP FALLING THROUGH A WARM LAYER WHICH BY 18Z IS FORECAST TO BE +3C AT KMSP AND EVEN WARMER AT POINTS SOUTHWARD. THE SURFACE WILL STILL BE IN THE 20S...SO THIS WOULD LEAD TO A BRIEF PERIOD OF SLEET/FREEZING RAIN ROUGHLY ALONG A LINE JUST SOUTH OF THE I-94 CORRIDOR...REACHING EAU CLAIRE BY LATE AFTERNOON. ACCUMULATIONS WOULD ONLY BE 1 OR 2 HUNDREDTHS...BUT EVEN THOSE MEAGER AMOUNTS COULD LEAD TO SLICK ROADWAYS. FOR NOW INCREASED THE POPS AND TRENDED TOWARDS THE LAST FEW RUNS OF THE HOPWRF AND HRRR WHICH HAVE SLOWED THE ONSET OF THIS PRECIP. ONCE THIS MOVES THROUGH H850 AIR OF +5 TO +7 WILL REMAIN IN PLACE OVERNIGHT...AS SOUTHEASTERLY WINDS GRADUALLY VEER TO A SOUTHERLY DIRECTION BY SATURDAY MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 357 AM CST FRI NOV 28 2014 STRONG WARM AIR ADVECTION WILL BE THE PREVAILING STORY SATURDAY WITH A WMFNT WELL N OF THE WFO MPX CWFA AND AN INCOMING ARCTIC HIGH PRES AIRMASS THAT LOOKS TO DROP THE HAMMER ON TEMPERATURES GOING INTO SUNDAY. NOT LOOKING FOR MUCH OF ANYTHING IN TERMS OF PRECIPITATION SO SATURDAY WILL RESULT IN MOSTLY CLOUDY SKIES DUE TO INCREASED MOISTURE PROMOTING STRATUS DEVELOPMENT OVER A DECENT SNOWPACK AND FAIRLY WIDESPREAD NVA KEEPING PRECIP N OF THE AREA. DESPITE THE CLOUD COVER...THE STRONG WAA WILL FORCE HIGHS INTO THE UPR 30S AND EVEN LWR 40S. BY LATE EVENING...A POTENT CDFNT WILL DROP THRU THE CWFA...WHICH WILL HELP SCOUR OUT SOME OF THE CLOUD COVER BUT IS NOT XPCTD TO PRODUCE MUCH...IF ANY...PRECIP FOR THE CWFA. WINDS WILL KICK UP BUT THE MAIN EFFECT WILL BE TO SIGNIFICANTLY DROP TEMPERATURES FOR SUNDAY...WITH HIGHS ONLY REACHING THE LWR TEENS TO LWR 20S. THE ARCTIC HIGH PRES AIRMASS WILL PERSIST THRU MON...PRODUCING HIGHS ONLY IN THE SINGLE DIGITS ABOVE ZERO DESPITE PLENTY OF SUNSHINE. AS THE HIGH PRES AREA SHIFTS OFF TO THE E FOR THE MIDDLE PORTION OF NEXT WEEK...A MORE SOUTHERLY FLOW ON THE BACKSIDE WILL ALLOW SOME MODERATION IN TEMPERATURES BUT STILL BELOW THE FREEZING MARK. HIGHS WILL CLIMB INTO THE 20S...WITH VERY LITTLE CHANCES OF PRECIP GOING THROUGH THE WEEK. THERE ARE STILL SOME INDICATIONS OF A MORE ORGANIZED LOW PRES SYSTEM MOVING THRU THE CENTRAL CONUS MID-TO-LATE NEXT WEEK BUT MODEL CONSENSUS...AND HENCE FORECAST CONFIDENCE...REMAINS LOW IN THIS THINKING SO HAVE KEPT MUCH OF THE AREA DRY THRU NEXT WEEK. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1103 PM CST THU NOV 27 2014 A BAND OF WAA SNOW WILL PUSH ACROSS EASTERN MN AND WESTERN WI EARLY THIS MORNING. CEILINGS AND VISIBILITIES WILL DROP TO IFR FOR A SEVERAL HOUR PERIOD. IN THE WAKE OF THE BAND OF SNOW...A LOSS OF MID LEVEL CLOUDS/ICE CRYSTALS IS STILL SEEN IN SHORT TERM GUIDANCE. THIS MAY LEAD TO SOME LIGHT FREEZING DRIZZLE FRIDAY MORNING. CONFIDENCE IS NOT REAL HIGH ON OCCURRENCE AND A PROB GROUP WAS USED AT MOST OF THE TAF SITES. ANOTHER WEAK WEATHER DISTURBANCE WILL MOVE ACROSS CENTRAL MN AND WEST CENTRAL WI FRIDAY EVENING. PROFILE DATA INDICATES A RATHER SIGNIFICANT WARM LAYER ALOFT WITH SLEET BEING THE PRECIPITATION TYPE. CONFIDENCE IS NOT HIGH ON THIS OCCURRING AS IT HAS RECENTLY BEGUN TO SHOW UP IN MODEL DATA THIS EVENING. AGAIN...USED A PROB GROUP FROM KSTC THROUGH KEAU. SE WINDS 6-12 KNOTS OVERNIGHT BECOMING ESE 4-6 KNOTS FRIDAY AFTERNOON AND EVENING. KMSP...A BAND OF IFR SNOW WILL MOVE THROUGH IN THE 06Z-08Z TIME FRAME WITH MVFR CONDITIONS/-SN THROUGH DAYBREAK. SNOW ACCUMULATION OVERNIGHT UP TO AN INCH. A THREAT REMAINS FRIDAY MORNING/EARLY AFTERNOON FOR SOME FREEZING DRIZZLE. MOVED THE OCCURRENCE TO A PROB GROUP DUE TO LOWER CONFIDENCE. PUSHED CEILINGS TO VFR FRIDAY EVENING AS THE WARM FRONT MOVES EAST OF THE AIRFIELD. /OUTLOOK FOR KMSP/ SUN...VFR. WINDS NW 15-20 KTS. MON...VFR. WINDS NW 5-10KTS...BECOMING S LATE. TUE...VFR. WINDS S 15-20 KTS...BECOMING W. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR MNZ045- 052-053. WI...WINTER WEATHER ADVISORY UNTIL 4 PM CST THIS AFTERNOON FOR WIZ014>016. && $$ SHORT TERM...JRB LONG TERM...JPC AVIATION...RAH
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
516 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 358 AM CST FRI NOV 28 2014 TODAY AND TONIGHT...A CHECK ON UPPER LEVEL MOISTURE IN THE NAM...GFS AND RAP MODELS INDICATES AN INCREASE TODAY. UPPER LEVEL WINDS ALSO INCREASE BY 10 TO 15 KT. THIS WOULD SUGGEST THE POTENTIAL FOR CIRRUS DEVELOPING OFF THE LARAMIE RANGE WHICH WOULD SPREAD EAST DURING THE AFTN. THE AMOUNT OF COVERAGE RANGES FROM TOTALLY OVERCAST IN THE GFS TO NEARLY NONE IN THE RAP. THE TEMPERATURE FORECAST USES A MIDDLE OF THE ROAD APPROACH FOR PARTLY CLOUDY CONDITIONS. THE RAP AND NAM ALSO SHOW A WEAK COLD FRONT DROPPING THROUGH NRN NEBRASKA THIS AFTN WHICH WOULD KEEP THE NORTH MOSTLY IN THE 50S FOR HIGHS. SOUTH OF THE FRONT...DESPITE THE HIGH CLOUDS...DEEPER MIXING IS EXPECTED WHICH SHOULD SEND HIGHS INTO THE 60S TO LOWER 70S...NEAR RECORD. TONIGHT...THE MODELS SHOW THE UPPER LEVELS DRYING OUT WHICH WOULD BE ALL FOR CLEARING...LIGHT WINDS AND RADIATIONAL COOLING THE IN THE N/S PLATTE VALLEYS. THE HIGHLANDS STAY MIXED. LOWS TONIGHT RANGE FROM THE LOWER 20S IN THE VALLEYS TO UPPER 30S ACROSS THE SANDHILLS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 358 AM CST FRI NOV 28 2014 FORECAST CONCERNS DEAL WITH TEMPERATURES AND WINDS...AND FIRE WEATHER POTENTIAL FOR SATURDAY. THE NEXT WEEK LOOKS LARGELY DRY ALTHOUGH IT IS POSSIBLE FOR A FEW SNOW SHOWERS /FLURRIES/ WITH LITTLE OR NO ACCUMULATION SATURDAY NIGHT INTO MONDAY MORNING. MODELS HAVE DECENT AGREEMENT THROUGH THE PERIOD NOW SO CONFIDENCE IS IMPROVING WITH THE SENSIBLE WEATHER CONDITIONS FOR THIS FORECAST CYCLE. THE PERIOD BEGINS WITH A VERY ANOMALOUSLY WARM DAY FOR SATURDAY. VERY LITTLE RUN TO RUN CHANGES HAVE BEEN NOTICED ACROSS THE AREA SO GOOD CONFIDENCE ON A VERY WARM DAY. THE IMPENDING STRONG COLD FRONT WILL STAY UP OVER SOUTH DAKOTA THROUGH 00Z SUNDAY WITH THE SURFACE PATTERN SHOWING WESTERLY WINDS ACROSS NEBRASKA. THE WESTERLY COMPONENT OF THE WINDS WILL GIVE THE AIR IN THE BOUNDARY LAYER WARMING DOWNSLOPE CONDITIONS. THE MODELS AREN/T PARTICULARLY STRONG WITH THE WINDS AS THE PRESSURE GRADIENT IS QUITE WEAK BUT DEEPER MIXING INTO THE AFTERNOON SHOULD PROVIDE BREEZY CONDITIONS IN PLACES. THE STRONGER WINDS AT THE TOP OF THE MIXED LAYER ARE ACROSS NORTHERN NEBRASKA AT 20 TO 30KTS. GOING SOUTH...THE SOUTHERN PART OF THE STATE SEES WINDS AT THE SAME LEVEL ONLY AT 10 TO 15KTS. HAVE INCLUDED THE HIGHER WINDS OVER THE NORTHERN AREAS AND LOWER WINDS ACROSS THE SOUTH IN THE FORECAST TODAY. LOOKING INTO HIGHS...MINIMAL CHANGES WERE MADE TO ONGOING FORECAST. THIS LEAVES HIGHS IN THE 60S...WITH LOW 70S OVER THE SOUTHERN PART OF THE STATE. STANDARDIZED ANOMALIES CONTINUE TO SHOW TEMPERATURES AT 850MB AT 2-3 STANDARD DEVIATIONS ABOVE NORMAL. THINKING THIS WILL BE CLOSE TO THE HEIGHT OF THE MIXED LAYER...LIKELY HIGHER OVER THE HIGHER TERRAIN IN THE WESTERN PART OF THE FORECAST AREA SO AGAIN...ONGOING TEMPERATURES LOOK APPROPRIATE WHICH WILL BE NEAR RECORD READINGS. THE OTHER CONCERN WITH SATURDAY WILL BE NEAR CRITICAL FIRE WEATHER POTENTIAL. THE WARM TEMPERATURES AND DRY AIR IN PLACE WILL DROP RELATIVE HUMIDITY DOWN BELOW 20 PERCENT...MAINLY FROM SOUTHWEST NEBRASKA INTO THE EASTERN SANDHILLS. AT THIS TIME...THE STRONGER WINDS DON/T LOOK TO COINCIDE WITH THE DRIER CONDITIONS SO NOT ANTICIPATING THE NEED FOR FIRE WEATHER HEADLINES DESPITE THE WARM AND DRY CONDITIONS. THE COLD FRONT WILL PLOW SOUTH THROUGH THE FORECAST AREA SATURDAY NIGHT. THIS FRONT WILL DROP TEMPERATURES DRAMATICALLY WITH 850MB VALUES LOWERING FROM 13-18C AT 00Z SUNDAY TO -17C TO -10C BY 00Z MONDAY. THIS WILL KEEP THE DIURNAL TEMPERATURE CHANGE VERY MINIMAL ON SUNDAY AND TEMPERATURES WILL ONLY RAISE INTO THE 20S FOR MUCH OF THE AREA. ALSO THINKING WINDS WILL INCREASE BEHIND THE FRONT AND HAVE TRENDED THE FORECAST ACCORDINGLY FOR SATURDAY NIGHT AND SUNDAY. NEARLY UNIDIRECTIONAL WINDS FROM THE NORTH- NORTHWEST...STRONG COLD AIR ADVECTION...GOOD SUBSIDENCE...AND A TIGHT PRESSURE GRADIENT ALL ARE GOOD INGREDIENTS FOR BREEZY TO STRONG WINDS. THE MODELS ARE INDICATING SOME FRONTOGENETICAL FORCING ALONG THE FRONT SATURDAY NIGHT. MOISTURE ISN/T VERY IMPRESSIVE AND REALLY NOT MUCH LIFT IN THE LAYER SO JUST ADDED IN SOME FLURRIES FOR NOW IN AREAS. THEN...ON SUNDAY NIGHT AS THE SURFACE HIGH BUILDS SOUTHEAST INTO EASTER SOUTH DAKOTA RETURN FLOW WILL BE IN PLACE FROM WESTERN KANSAS INTO THE NEBRASKA PANHANDLE. THIS WILL BRING SOME INCREASED MOISTURE INTO LEVELS BELOW 700MB. ALTHOUGH THE MOISTURE DOES INCREASE...THE LIFT IN THE LAYER ISN/T VERY IMPRESSIVE SO DIDN/T HAVE THE CONFIDENCE TO ADD MEASURABLE SNOW IN THE FORECAST YET AND JUST INCLUDED SOME FLURRIES FOR PORTIONS OF THE PANHANDLE SUNDAY NIGHT. MONDAY MORNING WILL BE QUITE COLD AS THE REGION IS INFLUENCED BY THE COLD AIR /850MB TEMPERATURES AT -12C TO -14C AND A SURFACE HIGH CENTERED OVER THE DAKOTAS. THE AIRMASS IN PLACE WOULD SUGGEST LOWS BELOW ZERO ARE CERTAINLY POSSIBLE WHERE WINDS DECOUPLE COMPLETELY AND BECOME CALM. THIS MAY STAY IN AREAS DIRECTLY UNDER THE SURFACE HIGH OVER SOUTH DAKOTA SO KEPT LOWS IN THE SINGLE DIGITS AT THIS TIME THOUGH DID DROP THEM A FEW DEGREES. THE NEXT WORK WEEK LOOKS TO BE A YO-YO IN TEMPERATURES WITH COLD CONDITIONS MONDAY AND WEDNESDAY AND A BIT WARMER FOR TUESDAY AND THURSDAY. THE HIGH DEPARTS MONDAY NIGHT WITH FAIRLY STRONG RETURN FLOW OCCURRING INTO TUESDAY TO PUSH OUT THE COLD AIR MASS WITH A RETURN OF CLOSE TO NEAR NORMAL TEMPERATURES IN THE 40S MOST PLACES. ANOTHER COLD FRONT WILL THEN MOVE THROUGH THE NORTHERN PLAINS AGAIN TUESDAY NIGHT AND MODELS HAVE COME INTO BETTER AGREEMENT IN ITS TIMING AND OTHER DETAILS. THIS FRONTAL PASSAGE LOOKS TO BE DRY AT THIS TIME BUT IT WILL BRING ANOTHER REINFORCING SHOT OF COLDER AIR...ALTHOUGH NOT NEARLY AS COLD AS THE SUNDAY SYSTEM. THEN THURSDAY LOOKS TO BRING STRONG WARM AIR ADVECTION BACK TO PERHAPS GET TEMPERATURES BACK ABOVE NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 516 AM CST FRI NOV 28 2014 VFR IS EXPECTED ALL AREAS TODAY AND TONIGHT. AN UPPER LOW ACROSS BRITISH COLUMBIA WILL MOVE VERY SLOWLY SOUTH. SCT/BKN HIGH CLOUDS WILL CONTINUE ACROSS WESTERN AND NORTH CENTRAL NEBRASKA DURING THIS TIME. && .FIRE WEATHER... ISSUED AT 317 AM CST FRI NOV 28 2014 TODAY...DEWPOINTS WHERE DERIVED FROM 50 PERCENT OF THE VERY DRY RAP MODEL AND 50 PERCENT OF THE OTHER MODELS. THIS PRODUCES RH VALUES BETWEEN 15 AND 20 PERCENT SOUTH OF INTERSTATE 80. WINDS SHOULD BE LIGHT IN THIS AREA AS THE RAP SHOWS A SFC TROF SETTING UP ACROSS THE SOUTH. SO VERY HIGH FIRE DANGER IS EXPECTED BUT WINDS ARE LIGHT GUSTING TO JUST 20 MPH. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...BROOKS AVIATION...CDC FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
946 AM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 946 AM CST FRI NOV 28 2014 THERE HAVE BEEN SOME REPORTS OF SLEET AND FREEZING RAIN IN A FEW SPOTS IN OUR SOUTHWESTERN COUNTIES...WHICH IS SUPPORTED BY BUFKIT SOUNDINGS. GIVEN THE SCATTERED NATURE OF THE FREEZING RAIN/SLEET SHOWERS AND THE FACT THAT THE SHORT TERM MODELS HAVE THIS ACTIVITY DISSIPATING IN THE NEXT HOUR OR SO WILL KEEP ANY HEADLINES OUT FOR NOW AND JUST GO WITH A NOWCAST. HOWEVER WILL KEEP AN EYE ON THINGS IN CASE THE ACTIVITY PERSISTS LONGER THAN EXPECTED. UPDATE ISSUED AT 706 AM CST FRI NOV 28 2014 WILL MAINTAIN A SCATTERED TYPE POP THIS MORNING OVER THE FCST AREA. RADAR HAS BEEN SHOWING SOME VERY LIGHT SNOW MOVING INTO DVL BASIN-LANGDON AREAS. OF MORE INTEREST IS CONVECTIVE SHOWERS THAT WERE IN EASTERN MT EARLIER THEY ARE MOVING QUICKLY TOWARD LISBON- VALLEY CITY AND WILL MOVE INTO FARGO AREA. COVERAGE HAS DIMINISHED A TAD....BUT PTYPE IS WHAT IS MOST IMPORTANT. BUFKIT SOUNDINGS WOULD INDICATE SLEET PSBL IN JAMESTOWN BUT THEN MORE OF A SNOW SOUNDING FARTHER EAST AS DEPTH OF COLD AIR IS QUITE DEEP AS YOU MOVE EAST. FOR NOW WILL MAINTAIN PREV PTYPE GRIDS WHICH IS SNOW FOR VALLEY CITY-FARGO AND SOME SLEET/SNOW IN FORMAN/GWINNER AREA. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 MODELS HAVE IN GENERAL HANDLED THINGS VERY POORLY LATELY. WHAT WAS GOING TO BE A DECENT SNOW CLIPPERY SYSTEM LAST NIGHT WAS ANYTHING BUT. BAROCLINIC ZONE REMAINED WELL SOUTH AND WEST OF WHAT WAS PROGGED 24 HOURS AGO AND THUS MAIN 1 TO 2 INCH BAND WAS FROM MINOT AREA TO JAMESTOWN TO ALEXANDRIA MN INSTEAD OF BEING FARTHER NORTH. AMOUNTS WEAKER AS WELL AS FOCUS OF WARM ADVECTION AND LIFT SEEMED MORE CONFINED TO ERN SD/WCNTRL MN JUST OUTSIDE OF MAIN PRECIP BAND. ANYHOW FIRST PRECIP BAND OF LIGHT SNOW EASTERN MN INTO WISCONSIN. THERE IS A LARGER AREA OF LIGHT SNOW UPSTREAM IN SASKATCHEWAN INTO SW MANITOBA AND TRYING TO SPREAD INTO NCNTRL ND. LATEST RAP/NAM SEEM OK IN SHOWING THIS LIGHT SNOW SPREADING INTO NRN VALLEY AND PARTS OF NW MN THIS MORNING BEFORE DRYING UP. THERE IS AN AREA OF CONVECTIVE SHOWERS THAT FORMED IN ECNTRL MONTANTA AND IS NOW NORTHWEST OF BISMARCK. RAP HAS SOME PRECIP SURVIVING AND MOVING INTO PARTS OF ECNTRL OR SE ND 12Z-15Z PERIOD. SO WITH CHANCES OF LIGHT SNOW NORTH AND SOUTH KEPT PRETTY BROAD POPS THRU 18Z FRI. TOP DOWN DID SHOW SOME RISK OF SLEET IN FAR SOUTHEASTERN ND IF PRECIP REACHES THAT AREA. THIS AFTN PRETTY QUIET MOST AREAS...THOUGH LINGERING LIGHT SNOW CHANCES FAR NORTH. BUT MAIN 850 MB WARM ADVECTION RETURNS BACK TO CENTRAL SASKATCHEWAN THIS AFTN AHEAD OF SHROT WAVE AND SFC LOW IN SOUTHERN B.C. THIS SYSTEM TO MOVE INTO NORTH CENTRAL ND SATURDAY MORNING WITH MAIN AREA OF WARM ADV SNOWS NORTH OF THE INTL BORDER. THOUGH DID KEEP SOME POPS IN NRN FCST AREA AS SRN EDGE MAY IMPACT AREAS ALONG THE BORDER. QUITE WARM AIR BUILDS INTO THE SOUTHERN HALF OF THE FCST AREA LATER TONIGHT INTO SATURDAY SO HIGHS TODAY WILL BE NEAR LOWS TONIGHT IN MANY AREAS AND THEN RISING TO SOME LOWER OR MID 30S IN THE FAR SOUTH SATURDAY WITH SOUTH WINDS WHILE NORTH WINDS RETURN TO DVL BASIN AND FAR NRN VALLEY AS LOW MOVES EAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 LOW WILL MOVE EAST THRU NRN MN WITH COLD FRONT MOVING SOUTH THRU THE FCST AREA. SOME LIGHT SNOW WITH FRONT BUT NOTHING MUCH. VERY COLD AIRMASS MOVES IN SUNDAY WITH HIGHS LIKELY STAYING BELOW ZERO IN FAR NORTHERN ND. HIGH PRESSURE MOVES IN SUN NIGHT INTO CNTRL ND WITH CLEAR SKY AND DID GO A BIT LOWER THAN SUPERBLEND BASED ON WED NIGHTS LOWS. SUSPECT -20S AGAIN IN THE DVL BASIN. MONDAY TO THURSDAY...OVERALL DRY AND COLD AS THE PERIOD BEGINS WITH SFC HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS AND AN ARCTIC AIRMASS IN PLACE. THE NEXT SHORT WAVE MOVES ACROSS THE INTERNATIONAL BORDER ON MONDAY NIGHT INTO TUESDAY ALLOWING FOR WEAK AND BRIEF RIDGING SCOURING OUT THE WELL BELOW NORMAL COLD AIRMASS. NW FLOW IN THE WAKE OF THIS SHORT WAVE IS NOT AS AMPLIFIED...RESULTING IN A LESS COLD AIRMASS...WITH 850MB TEMPS IN THE 10 TO 18 BELOW RANGE FOR WEDNESDAY. ZONAL FLOW APPEARS TO DEVELOP UP THURSDAY WITH TEMPS REBOUNDING INTO THE 20S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 706 AM CST FRI NOV 28 2014 A MIXED BACK OF CEILINGS THIS MORNING AND LIKELY THRU TONIGHT WITH MAJORITY MVFR CIGS 15-25 KFT WITH SOME SCATTERED MVFR CLOUD THEN CIGS IN THE 5-7 KFT RANGE. SOUTHEAST WIND 10 TO 15 KTS EXPECTED TO CONTINUE BUT TURNING A BIT MORE SOUTH-SOUTHEAST TONIGHT. PATCHY LIGHT SNOW THIS MORNING AND INCLUDED IN MOST TAFS SOME MENTION OF -SN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...RIDDLE LONG TERM...JK/RIDDLE AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
710 AM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 706 AM CST FRI NOV 28 2014 WILL MAINTAIN A SCATTERED TYPE POP THIS MORNING OVER THE FCST AREA. RADAR HAS BEEN SHOWING SOME VERY LIGHT SNOW MOVING INTO DVL BASIN-LANGDON AREAS. OF MORE INTEREST IS CONVECTIVE SHOWERS THAT WERE IN EASTERN MT EARLIER THEY ARE MOVING QUICKLY TOWARD LISBON- VALLEY CITY AND WILL MOVE INTO FARGO AREA. COVERAGE HAS DIMINISHED A TAD....BUT PTYPE IS WHAT IS MOST IMPORTANT. BUFKIT SOUNDINGS WOULD INDICATE SLEET PSBL IN JAMESTOWN BUT THEN MORE OF A SNOW SOUNDING FARTHER EAST AS DEPTH OF COLD AIR IS QUITE DEEP AS YOU MOVE EAST. FOR NOW WILL MAINTAIN PREV PTYPE GRIDS WHICH IS SNOW FOR VALLEY CITY-FARGO AND SOME SLEET/SNOW IN FORMAN/GWINNER AREA. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 MODELS HAVE IN GENERAL HANDLED THINGS VERY POORLY LATELY. WHAT WAS GOING TO BE A DECENT SNOW CLIPPERY SYSTEM LAST NIGHT WAS ANYTHING BUT. BAROCLINIC ZONE REMAINED WELL SOUTH AND WEST OF WHAT WAS PROGGED 24 HOURS AGO AND THUS MAIN 1 TO 2 INCH BAND WAS FROM MINOT AREA TO JAMESTOWN TO ALEXANDRIA MN INSTEAD OF BEING FARTHER NORTH. AMOUNTS WEAKER AS WELL AS FOCUS OF WARM ADVECTION AND LIFT SEEMED MORE CONFINED TO ERN SD/WCNTRL MN JUST OUTSIDE OF MAIN PRECIP BAND. ANYHOW FIRST PRECIP BAND OF LIGHT SNOW EASTERN MN INTO WISCONSIN. THERE IS A LARGER AREA OF LIGHT SNOW UPSTREAM IN SASKATCHEWAN INTO SW MANITOBA AND TRYING TO SPREAD INTO NCNTRL ND. LATEST RAP/NAM SEEM OK IN SHOWING THIS LIGHT SNOW SPREADING INTO NRN VALLEY AND PARTS OF NW MN THIS MORNING BEFORE DRYING UP. THERE IS AN AREA OF CONVECTIVE SHOWERS THAT FORMED IN ECNTRL MONTANTA AND IS NOW NORTHWEST OF BISMARCK. RAP HAS SOME PRECIP SURVIVING AND MOVING INTO PARTS OF ECNTRL OR SE ND 12Z-15Z PERIOD. SO WITH CHANCES OF LIGHT SNOW NORTH AND SOUTH KEPT PRETTY BROAD POPS THRU 18Z FRI. TOP DOWN DID SHOW SOME RISK OF SLEET IN FAR SOUTHEASTERN ND IF PRECIP REACHES THAT AREA. THIS AFTN PRETTY QUIET MOST AREAS...THOUGH LINGERING LIGHT SNOW CHANCES FAR NORTH. BUT MAIN 850 MB WARM ADVECTION RETURNS BACK TO CENTRAL SASKATCHEWAN THIS AFTN AHEAD OF SHROT WAVE AND SFC LOW IN SOUTHERN B.C. THIS SYSTEM TO MOVE INTO NORTH CENTRAL ND SATURDAY MORNING WITH MAIN AREA OF WARM ADV SNOWS NORTH OF THE INTL BORDER. THOUGH DID KEEP SOME POPS IN NRN FCST AREA AS SRN EDGE MAY IMPACT AREAS ALONG THE BORDER. QUITE WARM AIR BUILDS INTO THE SOUTHERN HALF OF THE FCST AREA LATER TONIGHT INTO SATURDAY SO HIGHS TODAY WILL BE NEAR LOWS TONIGHT IN MANY AREAS AND THEN RISING TO SOME LOWER OR MID 30S IN THE FAR SOUTH SATURDAY WITH SOUTH WINDS WHILE NORTH WINDS RETURN TO DVL BASIN AND FAR NRN VALLEY AS LOW MOVES EAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 LOW WILL MOVE EAST THRU NRN MN WITH COLD FRONT MOVING SOUTH THRU THE FCST AREA. SOME LIGHT SNOW WITH FRONT BUT NOTHING MUCH. VERY COLD AIRMASS MOVES IN SUNDAY WITH HIGHS LIKELY STAYING BELOW ZERO IN FAR NORTHERN ND. HIGH PRESSURE MOVES IN SUN NIGHT INTO CNTRL ND WITH CLEAR SKY AND DID GO A BIT LOWER THAN SUPERBLEND BASED ON WED NIGHTS LOWS. SUSPECT -20S AGAIN IN THE DVL BASIN. MONDAY TO THURSDAY...OVERALL DRY AND COLD AS THE PERIOD BEGINS WITH SFC HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS AND AN ARCTIC AIRMASS IN PLACE. THE NEXT SHORT WAVE MOVES ACROSS THE INTERNATIONAL BORDER ON MONDAY NIGHT INTO TUESDAY ALLOWING FOR WEAK AND BRIEF RIDGING SCOURING OUT THE WELL BELOW NORMAL COLD AIRMASS. NW FLOW IN THE WAKE OF THIS SHORT WAVE IS NOT AS AMPLIFIED...RESULTING IN A LESS COLD AIRMASS...WITH 850MB TEMPS IN THE 10 TO 18 BELOW RANGE FOR WEDNESDAY. ZONAL FLOW APPEARS TO DEVELOP UP THURSDAY WITH TEMPS REBOUNDING INTO THE 20S. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 706 AM CST FRI NOV 28 2014 A MIXED BACK OF CEILINGS THIS MORNING AND LIKELY THRU TONIGHT WITH MAJORITY MVFR CIGS 15-25 KFT WITH SOME SCATTERED MVFR CLOUD THEN CIGS IN THE 5-7 KFT RANGE. SOUTHEAST WIND 10 TO 15 KTS EXPECTED TO CONTINUE BUT TURNING A BIT MORE SOUTH-SOUTHEAST TONIGHT. PATCHY LIGHT SNOW THIS MORNING AND INCLUDED IN MOST TAFS SOME MENTION OF -SN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...RIDDLE SHORT TERM...RIDDLE LONG TERM...JK/RIDDLE AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
955 AM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL SLIDE OVER THE APPALACHIAN MOUNTAINS TODAY. WARMER AIR WILL GRADUALLY WORK INTO THE AREA FROM THE SOUTH THIS WEEKEND. A COLD FRONT WILL PUSH THROUGH LATE SUNDAY NIGHT AND THROUGH THE DAY ON MONDAY. FAST WESTERLY FLOW NEXT WEEK WILL BRING A COUPLE OF WEATHER SYSTEMS THROUGH BY NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... SNOW SHOWERS DECREASING IN INTENSITY AND COVERAGE THIS MORNING...BUT STILL A FEW ORGANIZED AREAS OVER WESTERN CWA MOVING SE AND DISSIPATING. THE RISING HEIGHTS/RIDGING DURING THE DAY WILL HELP TO DECREASE THE SNOW SHOWERS TO FLURRIES OR LESS LATE THIS MORNING. THE COLDEST LLVL AIR WILL BE OVERHEAD THIS AFTERNOON...SO TEMPERATURES WILL STAY COLD...NOT RISING OUT OF THE M20S NORTH AND M30S SOUTH. WESTERLY WINDS OF 10-15 MPH WILL MAKE IT FEEL EVEN CHILLIER. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE THERMAL TROUGH MOVES EAST AND GOOD SOUTHERLY FLOW STARTS TO DEVELOP TONIGHT. A WARM FRONT ALOFT WILL SLIDE OVERHEAD AND A SHORT WAVE TRAVELING ALONG IT WILL DROP DOWN FROM THE NORTHWEST TONIGHT. MEAGER MOISTURE MIGHT MAKE MEASURABLE SNOW OVER THE NORTHERN TWO-THIRDS OF THE REGION. THE FEATURE DRIVING THE SNOW WILL BE VERY FAST-MOVING AND THE TIMING AND HEIGHTS OVERHEAD AT THE TIME OF PASSAGE WILL MAKE A BIG DIFFERENCE WHERE THE SNOW FALLS. WILL BUMP POPS INTO LIKELIES FOR THE NRN HALF AND JUST A LITTLE MORE WITH CHCS ELSEWHERE TO COVER THE UNCERTAINTIES. SNOW AMOUNTS SHOULD BE ALMOST NIL ALONG THE MD BORDER...BUT COULD BE 2 INCHES ALONG AND NORTH OF I-80. TEMPS TONIGHT WILL DROP JUST 5-10F WITH CLOUDS THICKENING UP AND LIGHT SOUTHERLY WINDS. THE TEMPS ALOFT CONTINUE TO WARM ON SATURDAY...AND THE LEFTOVER LIGHT SNOW IN THE EAST IN THE MORNING WILL BE SHUNTED OFF TO THE EAST. LOW PRESSURE WILL PASS OVER LAKE SUPERIOR LATE SATURDAY...AND WE WILL BE IN THE WARM SECTOR. HOWEVER...THE SOUTHERLY WINDS...HIGHER DEWPOINT AIR AND MINORLY MELTING SNOW WILL LIKELY LEAD TO SOME FOG AND LOW CLOUDS WHICH COULD BEAR DRIZZLE/LIGHT RAIN. LIQUID PRECIP DEVELOPS OVER WRN AND NRN PA LATE SAT AND ALMOST CERTAINLY ON SAT NIGHT. THE SFC TEMPS SAT NIGHT COULD LEAD TO FREEZING RAIN OVER THE NRN TIER. WILL JUST ADD IN A MENTION OF IT WITH THIS PKG BUT CALL IT RAIN ELSEWHERE. && .LONG TERM /SUNDAY THROUGH THURSDAY/... BROAD ZONAL FLOW DEVELOPS DURING THE WEEKEND. TEMPS WILL BE REACHING INTO THE MID 40S TO MID 50S BY SUNDAY. MODELS SEEM TO BE BACK IN BETTER AGREEMENT ON APPROACH OF A FRONT FOR MONDAY...THOUGH GFS/GEFS CONTINUE TO BE 6 TO MAYBE 12 HRS FASTER WITH FROPA THAN THE ECMWF. POST FRONTAL WINDS WILL BRING COOLER TEMPS BACK IN FOR TUESDAY AS LARGE SURFACE HIGH SLIDES ACROSS S CANADA. MDLS IN PRETTY GOOD AGREEMENT ON LARGE FEATURES FOR NEXT WEEK. GFS DOES MAKE A MORE- WET FRONTAL PASSAGE AT THE END OF THE WEEK...BUT ALL MDLS SEEM TO BE LATCHING ONTO THE FROPA NEXT FRI. && .AVIATION /15Z FRIDAY THROUGH TUESDAY/... LAKE ENHANCED...OROGRAPHIC SNOW SHOWERS WILL BE THE PRIMARY AVIATION CONCERN EARLY THIS MORNING ACROSS THE W MTNS. CAN/T RULE OUT A BRIEF DIP TO IFR CONDS AT EITHER KBFD OR JST THIS MORNING. HOWVEVER...RADAR TRENDS AND HRRR OUTPUT AT 11Z POINT TOWARD IMPROVING CONDS. A RIDGE OF HIGH PRES BUILDING IN FROM THE OHIO VALLEY SHOULD CAUSE ANY LINGERING -SHSN OVR THE W MTNS TO DISSIPATE BY LATE AM...WITH WIDESPREAD VFR CONDS LIKELY BY THIS AFTN. A WARM FRONT LIFTING INTO THE REGION COULD PRODUCE A PERIOD OF LGT SNOW/REDUCED VSBYS LATE TONIGHT OR EARLY SAT AM OVER NORTHERN PA. OUTLOOK... SAT...AM LGT SNOW/REDUCED VSBYS POSS...MAINLY NORTH. LOW CIGS AT KBFD POSS SAT NIGHT. SUN...AM LOW CIGS/DZ POSS KBFD. MON...LOW CIGS/SHRA POSS...MAINLY W MTNS. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...ROSS SHORT TERM...DANGELO LONG TERM...DANGELO/RXR AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
642 AM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL SLIDE OVER THE APPALACHIAN MOUNTAINS TODAY. WARMER AIR WILL GRADUALLY WORK INTO THE AREA FROM THE SOUTH THIS WEEKEND. A COLD FRONT WILL PUSH THROUGH LATE SUNDAY NIGHT AND THROUGH THE DAY ON MONDAY. FAST WESTERLY FLOW NEXT WEEK WILL BRING A COUPLE OF WEATHER SYSTEMS THROUGH BY NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPPER TROUGH AXIS IS TO THE EAST OF THE AREA. BRIEFLY INTENSE SNOW SHOWERS WILL BRING ANOTHER INCH OR SO TO SOMERSET COUNTY EARLY THIS MORNING. OTHER SCATTERED SNOW SHOWERS WILL BE LIGHTER AND MORE-TRANSIENT. THESE SHOULD NOT MAKE ANY MORE THAN A DUSTING TO HALF INCH OF SNOW THIS MORNING. THE RISING HEIGHTS/RIDGING DURING THE DAY WILL HELP TO DECREASE THE SNOW SHOWERS TO FLURRIES OR LESS LATE THIS MORNING. THE COLDEST LLVL AIR WILL BE OVERHEAD THIS AFTERNOON...SO TEMPERATURES WILL STAY COLD...NOT RISING OUT OF THE M20S NORTH AND M30S SOUTH. WESTERLY WINDS OF 10-15 MPH WILL MAKE IT FEEL EVEN CHILLIER. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE THERMAL TROUGH MOVES EAST AND GOOD SOUTHERLY FLOW STARTS TO DEVELOP TONIGHT. A WARM FRONT ALOFT WILL SLIDE OVERHEAD AND A SHORT WAVE TRAVELING ALONG IT WILL DROP DOWN FROM THE NORTHWEST TONIGHT. MEAGER MOISTURE MIGHT MAKE MEASURABLE SNOW OVER THE NORTHERN TWO-THIRDS OF THE REGION. THE FEATURE DRIVING THE SNOW WILL BE VERY FAST-MOVING AND THE TIMING AND HEIGHTS OVERHEAD AT THE TIME OF PASSAGE WILL MAKE A BIG DIFFERENCE WHERE THE SNOW FALLS. WILL BUMP POPS INTO LIKELIES FOR THE NRN HALF AND JUST A LITTLE MORE WITH CHCS ELSEWHERE TO COVER THE UNCERTAINTIES. SNOW AMOUNTS SHOULD BE ALMOST NIL ALONG THE MD BORDER...BUT COULD BE 2 INCHES ALONG AND NORTH OF I-80. TEMPS TONIGHT WILL DROP JUST 5-10F WITH CLOUDS THICKENING UP AND LIGHT SOUTHERLY WINDS. THE TEMPS ALOFT CONTINUE TO WARM ON SATURDAY...AND THE LEFTOVER LIGHT SNOW IN THE EAST IN THE MORNING WILL BE SHUNTED OFF TO THE EAST. LOW PRESSURE WILL PASS OVER LAKE SUPERIOR LATE SATURDAY...AND WE WILL BE IN THE WARM SECTOR. HOWEVER...THE SOUTHERLY WINDS...HIGHER DEWPOINT AIR AND MINORLY MELTING SNOW WILL LIKELY LEAD TO SOME FOG AND LOW CLOUDS WHICH COULD BEAR DRIZZLE/LIGHT RAIN. LIQUID PRECIP DEVELOPS OVER WRN AND NRN PA LATE SAT AND ALMOST CERTAINLY ON SAT NIGHT. THE SFC TEMPS SAT NIGHT COULD LEAD TO FREEZING RAIN OVER THE NRN TIER. WILL JUST ADD IN A MENTION OF IT WITH THIS PKG BUT CALL IT RAIN ELSEWHERE. && .LONG TERM /SUNDAY THROUGH THURSDAY/... BROAD ZONAL FLOW DEVELOPS DURING THE WEEKEND. TEMPS WILL BE REACHING INTO THE MID 40S TO MID 50S BY SUNDAY. MODELS SEEM TO BE BACK IN BETTER AGREEMENT ON APPROACH OF A FRONT FOR MONDAY...THOUGH GFS/GEFS CONTINUE TO BE 6 TO MAYBE 12 HRS FASTER WITH FROPA THAN THE ECMWF. POST FRONTAL WINDS WILL BRING COOLER TEMPS BACK IN FOR TUESDAY AS LARGE SURFACE HIGH SLIDES ACROSS S CANADA. MDLS IN PRETTY GOOD AGREEMENT ON LARGE FEATURES FOR NEXT WEEK. GFS DOES MAKE A MORE- WET FRONTAL PASSAGE AT THE END OF THE WEEK...BUT ALL MDLS SEEM TO BE LATCHING ONTO THE FROPA NEXT FRI. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... LAKE ENHANCED...OROGRAPHIC SNOW SHOWERS WILL BE THE PRIMARY AVIATION CONCERN EARLY THIS MORNING ACROSS THE W MTNS. CAN/T RULE OUT A BRIEF DIP TO IFR CONDS AT EITHER KBFD OR JST THIS MORNING. HOWVEVER...RADAR TRENDS AND HRRR OUTPUT AT 11Z POINT TOWARD IMPROVING CONDS. A RIDGE OF HIGH PRES BUILDING IN FROM THE OHIO VALLEY SHOULD CAUSE ANY LINGERING -SHSN OVR THE W MTNS TO DISSIPATE BY LATE AM...WITH WIDESPREAD VFR CONDS LIKELY BY THIS AFTN. A WARM FRONT LIFTING INTO THE REGION COULD PRODUCE A PERIOD OF LGT SNOW/REDUCED VSBYS LATE TONIGHT OR EARLY SAT AM OVER NORTHERN PA. OUTLOOK... SAT...AM LGT SNOW/REDUCED VSBYS POSS...MAINLY NORTH. LOW CIGS AT KBFD POSS SAT NIGHT. SUN...AM LOW CIGS/DZ POSS KBFD. MON...LOW CIGS/SHRA POSS...MAINLY W MTNS. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...DANGELO/RXR AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
634 AM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL SLIDE OVER THE APPALACHIAN MOUNTAINS TODAY. WARMER AIR WILL GRADUALLY WORK INTO THE AREA FROM THE SOUTH THIS WEEKEND. A COLD FRONT WILL PUSH THROUGH LATE ON SUNDAY NIGHT AND MONDAY. FAST WESTERLY FLOW NEXT WEEK WILL BRING A COUPLE OF WEATHER SYSTEMS THROUGH BY NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... UPPER TROUGH IS SWINGING THROUGH UPSTATE NY...BUT HEIGHTS START TO RISE VERY SOON. BRIEFLY INTENSE SNOW SHOWERS WILL BRING A NEW 1-3 INCHES OF SNOW EARLY THIS MORNING TO THE LAUREL MOUNTAINS. TRANSIENT SHOWERS SHOULD KEEP A WIDESPREAD 3 INCHES FROM OCCURRING. RIDGING WILL HELP TO DECREASE THE SNOW SHOWERS ROLLING THROUGH WESTERN AND SOUTH-CENTRAL PA TO FLURRIES OR LESS BY LATE THIS MORNING. COLDEST LLVL AIR WILL BE OVERHEAD THIS AFTERNOON...SO TEMPERATURES WILL STAY COLD...NOT RISING OUT OF THE M20S NORTH AND M30S SOUTH. WESTERLY WINDS OF 10-15 MPH WILL MAKE IT FEEL EVEN CHILLIER. && .SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/... THE THERMAL TROUGH MOVES EAST AND GOOD SOUTHERLY FLOW STARTS TO DEVELOP TONIGHT. A WARM FRONT ALOFT WILL SLIDE OVERHEAD AND A SHORT WAVE TRAVELING ALONG IT WILL DROP DOWN FROM THE NORTHWEST TONIGHT. MEAGER MOISTURE MIGHT MAKE MEASURABLE SNOW OVER THE NORTHERN TWO-THIRDS OF THE REGION. THE FEATURE DRIVING THE SNOW WILL BE VERY FAST-MOVING AND THE TIMING AND HEIGHTS OVERHEAD AT THE TIME OF PASSAGE WILL MAKE A BIG DIFFERENCE WHERE THE SNOW FALLS. WILL BUMP POPS INTO LIKELIES FOR THE NRN HALF AND JUST A LITTLE MORE WITH CHCS ELSEWHERE TO COVER THE UNCERTAINTIES. SNOW AMOUNTS SHOULD BE ALMOST NIL ALONG THE MD BORDER...BUT COULD BE 2 INCHES ALONG AND NORTH OF I-80. TEMPS TONIGHT WILL DROP JUST 5-10F WITH CLOUDS THICKENING UP AND LIGHT SOUTHERLY WINDS. THE TEMPS ALOFT CONTINUE TO WARM ON SATURDAY...AND THE LEFTOVER LIGHT SNOW IN THE EAST IN THE MORNING WILL BE SHUNTED OFF TO THE EAST. LOW PRESSURE WILL PASS OVER LAKE SUPERIOR LATE SATURDAY...AND WE WILL BE IN THE WARM SECTOR. HOWEVER...THE SOUTHERLY WINDS...HIGHER DEWPOINT AIR AND MINORLY MELTING SNOW WILL LIKELY LEAD TO SOME FOG AND LOW CLOUDS WHICH COULD BEAR DRIZZLE/LIGHT RAIN. LIQUID PRECIP DEVELOPS OVER WRN AND NRN PA LATE SAT AND ALMOST CERTAINLY ON SAT NIGHT. THE SFC TEMPS SAT NIGHT COULD LEAD TO FREEZING RAIN OVER THE NRN TIER. WILL JUST ADD IN A MENTION OF IT WITH THIS PKG BUT CALL IT RAIN ELSEWHERE. && .LONG TERM /SUNDAY THROUGH THURSDAY/... BROAD ZONAL FLOW DEVELOPS DURING THE WEEKEND. TEMPS WILL BE REACHING INTO THE MID 40S TO MID 50S BY SUNDAY. MODELS SEEM TO BE BACK IN BETTER AGREEMENT ON APPROACH OF A FRONT FOR MONDAY...THOUGH GFS/GEFS CONTINUE TO BE 6 TO MAYBE 12 HRS FASTER WITH FROPA THAN THE ECMWF. POST FRONTAL WINDS WILL BRING COOLER TEMPS BACK IN FOR TUESDAY AS LARGE SURFACE HIGH SLIDES ACROSS S CANADA. MDLS IN PRETTY GOOD AGREEMENT ON LARGE FEATURES FOR NEXT WEEK. GFS DOES MAKE A MORE- WET FRONTAL PASSAGE AT THE END OF THE WEEK...BUT ALL MDLS SEEM TO BE LATCHING ONTO THE FROPA NEXT FRI. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... LAKE ENHANCED...OROGRAPHIC SNOW SHOWERS WILL BE THE PRIMARY AVIATION CONCERN EARLY THIS MORNING ACROSS THE W MTNS. CAN/T RULE OUT A BRIEF DIP TO IFR CONDS AT EITHER KBFD OR JST THIS MORNING. HOWVEVER...RADAR TRENDS AND HRRR OUTPUT AT 11Z POINT TOWARD IMPROVING CONDS. A RIDGE OF HIGH PRES BUILDING IN FROM THE OHIO VALLEY SHOULD CAUSE ANY LINGERING -SHSN OVR THE W MTNS TO DISSIPATE BY LATE AM...WITH WIDESPREAD VFR CONDS LIKELY BY THIS AFTN. A WARM FRONT LIFTING INTO THE REGION COULD PRODUCE A PERIOD OF LGT SNOW/REDUCED VSBYS LATE TONIGHT OR EARLY SAT AM OVER NORTHERN PA. OUTLOOK... SAT...AM LGT SNOW/REDUCED VSBYS POSS...MAINLY NORTH. LOW CIGS AT KBFD POSS SAT NIGHT. SUN...AM LOW CIGS/DZ POSS KBFD. MON...LOW CIGS/SHRA POSS...MAINLY W MTNS. TUE...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DANGELO NEAR TERM...DANGELO SHORT TERM...DANGELO LONG TERM...RXR AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
538 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 221 AM CST FRI NOV 28 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED DEEP...POTENT TROUGHS OVER BRITISH COLUMBIA AND OFF THE COAST OF CALIFORNIA...RIDGING OVER THE WESTERN U.S. AND TROUGHING OVER THE EASTERN U.S.. A SHORTWAVE WAS EVIDENT RIDING THROUGH THE NORTHWEST FLOW FROM NORTHWEST MN INTO WESTERN WI. DPVA FROM THIS SHORTWAVE COMBINED WITH WARM ADVECTION AND PRECIPITABLE WATER NEAR 0.5 INCHES HAS HELPED SUPPORT AN AREA OF SNOW FROM CENTRAL MN INTO THE FORECAST AREA. THE AFOREMENTIONED WARM ADVECTION WAS NICELY EVIDENT AT 850MB FROM 00Z RAOBS WITH READINGS IN THE 8-12C RANGE IN WESTERN SOUTH DAKOTA AND NEBRASKA...COMPARED TO -10 TO -14C OVER THE FORECAST AREA. THIS TIGHT TEMPERATURE GRADIENT WAS ADVECTING EASTWARD BY A 30- 40 KT SOUTHWEST WIND PER VWP/PROFILER DATA. INTERESTINGLY TOO... SURFACE DEWPOINTS OVER WESTERN SOUTH DAKOTA AND NEBRASKA WERE IN THE 20S...ABOUT 10F WARMER THAN CURRENT TEMPERATURES OVER THE FORECAST AREA. GOOD MODEL AGREEMENT EXISTS ON THE 500MB FLOW PATTERN THROUGH THE SHORT TERM PERIOD...SHOWING THE WESTERN U.S. RIDGE FLATTENING OUT AND GETTING PUSHED EASTWARD BY THE POTENT BRITISH COLUMBIA TROUGH DROPPING INTO THE PACIFIC NORTHWEST. THIS PATTERN EVOLUTION RESULTS IN CONTINUOUS WARM AND MOIST AIR ADVECTION FROM SOUTH DAKOTA AND NEBRASKA TOWARDS THE FORECAST AREA. REGARDING THE CURRENT SNOW...REPRESENTED WELL BY 800-700MB FRONTOGENESIS...ANTICIPATING THE EASTWARD PUSH WITH THE UPPER FLOW WILL HELP KEEP THE SNOWBAND MOVING EASTWARD THROUGH THE DAY. THERE COULD BE A SECOND...CALL IT SURGE...OF SNOW AND FRONTOGENESIS DROPPING THROUGH NORTHERN WI LATE THIS MORNING INTO THIS AFTERNOON AS SUGGESTED BY HIGH RESOLUTION MODEL GUIDANCE. THEREFORE...HAVE KEPT THE WINTER WEATHER ADVISORY IN TACT FOR TAYLOR COUNTY. ALSO LATE THIS MORNING THROUGH THE AFTERNOON...WE MAY HAVE TO CONTEND WITH ANOTHER BAND OF PRECIPITATION. THIS BAND CAN CURRENTLY BE SEEN COMING INTO THE WESTERN DAKOTAS ASSOCIATED WITH A SHORTWAVE JUST WEST OF IT...WHICH THE 28.00Z GFS/NAM/HIRES-ARW/NMM AND LATEST RAP/HRRR WANT TO TRAVERSE IT ACROSS LOCATIONS SOUTHWEST OF I-94. THERE COULD BE MID-LEVEL SATURATION ISSUES IN THE WAKE OF THE CURRENT SNOW...BUT MODELS DO WANT TO SATURATE THINGS BACK UP. THEREFORE...HAVE ADDED SOME PRECIPITATION CHANCES. TRACK WISE... REFER THE MORE NORTHERN RAP/HRRR OVER THE FARTHER SOUTH NAM/HIRES- ARW/NMM AS THE FARTHER SOUTH MODELS ARE WAY TOO INTENSE AND TOO FAR SOUTH COMPARED TO CURRENT RADAR IMAGERY. PRECIPITATION TYPE BECOMES AN ISSUE WITH THIS WAVE AS WELL WITH WARMER AIR COMING IN ALOFT. COMPARING MODEL DERIVED REFLECTIVITY OUTPUT WITH THE MAXIMUM TEMPERATURE ALOFT...THE SOUTHWESTERN EDGE MAY POSE A MIX WITH SLEET OR EVEN FREEZING RAIN CONCERN. SINCE THERE IS VERY LOW CONFIDENCE ON ANY SLEET/FREEZING RAIN OCCURRING...HAVE NOT ISSUED ANY WINTER WEATHER ADVISORY FOR THIS WAVE OF PRECIPITATION. AS WE HEAD INTO TONIGHT...CONCERN SHIFTS TO THE CONTINUOUS ADVECTION OF LOW LEVEL MOISTURE. SURFACE DEWPOINTS LATE THIS AFTERNOON COULD BE AS HIGH AS THE MID TO UPPER 30S ALONG I-29 ON THE WESTERN EDGE OF THE SNOWPACK. AS THIS HIGHER MOISTURE TRIES TO ADVECT ACROSS THE SNOWPACK INTO THE FORECAST AREA...WHICH MAY ALREADY HAVE DECENT LOW LEVEL SATURATION FROM THE WAVES OF PRECIPITATION MOVING THROUGH TODAY...ANTICIPATING VERY LOW STRATUS AND FOG TO DEVELOP. WARMER AIR MOVING IN ALOFT NOTED BY 850MB TEMPS CLIMBING TO 6-10C SHOULD ONLY FURTHER STRENGTHEN AN INVERSION...AIDING IN TRAPPING THE LOW LEVEL MOISTURE. HIGHER TERRAIN LOCATIONS SHOULD BE MOST SUSCEPTIBLE TO FOG. LATER SHIFTS MAY NEED TO CONSIDER A DENSE FOG ADVISORY... PARTICULARLY ALONG AND SOUTH OF I-90. WITH THE STRATUS IN PLACE AND IN A GENERAL WARM ADVECTION REGIME...ANTICIPATING VERY LITTLE FALL IN TEMPERATURES TONIGHT FROM AFTERNOON HIGHS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 221 AM CST FRI NOV 28 2014 FOCUS OF ATTENTION FOR THE FIRST PART OF THE LONG TERM PERIOD IS SQUARELY ON THE POTENT TROUGH OVER THE PACIFIC NORTHWEST AT 12Z SATURDAY. MODELS ARE IN GOOD AGREEMENT MARCHING THIS FEATURE EASTWARD THROUGH THE WEEKEND WITH ITS AXIS OVER THE FORECAST AREA BY 12Z MONDAY. PRIOR TO ITS ARRIVAL...925MB TEMPS ARE PROGGED TO CONTINUING WARMING THROUGH THE DAY SATURDAY...CLIMBING TO PERHAPS AS MUCH AS 4-9C. DESPITE STRATUS AND MORNING FOG...THESE READINGS SHOULD ALLOW FOR HIGHS IN THE UPPER 30S TO MID 40S...WITH EVEN A SMALL CHANCE OF HITTING 50 IN VALLEY AREAS AS SUGGESTED BY THE REGIONAL CANADIAN. A SERIES OF TWO COLD FRONTS ARE THEN PROGGED TO MOVE THROUGH THE AREA DURING THE OVERNIGHT HOURS OF SATURDAY NIGHT INTO SUNDAY AS THE TROUGH APPROACHES...RESULTING IN A FALLING TEMPERATURE TREND. 925MB TEMPS PLUMMET TO -14C SOUTH TO -20C NORTH BY 12Z MONDAY. A 25-35KT NORTHWEST WIND AT 925MB SUNDAY INTO SUNDAY NIGHT ALSO ADDS IN A WIND CHILL FACTOR. LOWS SUNDAY NIGHT LOOK TO DROP INTO THE SINGLE DIGITS ABOVE ZERO...A NEAR 40 DEGREE TEMPERATURE DROP FROM SATURDAYS HIGHS. MAY HAVE TO WATCH FOR A POSSIBLE WIND CHILL ADVISORY MONDAY MORNING. PRECIPITATION CHANCES LOOK VERY LOW THROUGH THE WEEKEND DESPITE THE APPROACH OF THE POTENT TROUGH...MOSTLY DUE TO A LACK OF MOISTURE. MONDAY AND MONDAY NIGHT FEATURE CHILLY CONDITIONS AS AN ARCTIC HIGH PRESSURE AREA BUILDS INTO THE REGION FROM THE DAKOTAS. DESPITE ANOTHER SUNNY DAY LIKE YESTERDAY...HIGHS ON MONDAY SHOULD STRUGGLE TO CLIMB INTO THE TEENS. SOME PLACES IN SOUTHEAST MN AND NORTH CENTRAL WI MAY NOT EVEN GET TO 10 ABOVE. THIS SETS THE STAGE FOR TEMPERATURES TO TANK MONDAY EVENING WITH LIGHT WINDS. HOWEVER...THE HIGH DOES MOVE OFF TO THE EAST QUICKLY AFTER MIDNIGHT MONDAY NIGHT...RESULTING IN WARM ADVECTION ACROSS THE FORECAST AREA AND RISING TEMPERATURES. SO...THE BIG QUESTION IS HOW LOW CAN TEMPERATURES DROP PRIOR. THE EC AND CANADIAN SHOW POTENTIAL FOR 10S BELOW ZERO IN SOUTHEAST MN AND NORTH CENTRAL WI...WHEREAS MEX GUIDANCE IS MORE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. SPLIT THE DIFFERENCE FOR NOW FOR LOWS. FOR THE REST OF NEXT WEEK...ANOTHER TROUGH IS PROGGED TO DROP DOWN INTO THE REGION FOR TUESDAY INTO WEDNESDAY. MUCH OF THE COLD AIR WITH THIS TROUGH...AS WELL AS POTENTIAL FOR PRECIPITATION...STAYS TO THE NORTH OF THE FORECAST AREA. IN FACT...THERE SHOULD BE A GOOD REBOUND IN TEMPERATURES FOR TUESDAY AS 925MB TEMPS CLIMB TO -4 TO - 6C. WARM ADVECTION RETURNS FOR WEDNESDAY NIGHT INTO THURSDAY AS THE UPPER FLOW TURNS ZONAL AGAIN...ALLOWING FOR ANOTHER REBOUND FOR TEMPERATURES. HOWEVER...THERE ARE SUGGESTIONS IN THE 28.00Z GFS AND 27.18Z DGEX FOR SOME LIGHT PRECIPITATION TO SPREAD INTO THE REGION AS MOISTURE ALSO RETURNS. THE 28.00Z ECMWF/CANADIAN CONTINUE TO POINT DRY...BUT FOR NOW IN COLLABORATION WITH NEIGHBORING OFFICES HAVE INTRODUCED 20 PERCENT CHANCES FOR THURSDAY FROM A MODEL CONSENSUS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 538 AM CST FRI NOV 28 2014 THE BAND OF -SN HAS EXITED EAST OF THE TAF SITES AS OF 11Z...WITH VFR CIGS/VSBYS EXPECTED THRU THE MORNING. SOUTHERLY FLOW AND WARMING TEMPS EXPECTED TO PRODUCE BOUNDARY LAYER MOISTURE TO THE SOUTH FROM MELTING SNOW. THIS MOISTURE IS THEN BE TRAPPED UNDER A STRONG INVERSION NEAR 925MB THIS AFTERNOON AND TONIGHT. MVFR CLOUD DECKS EXPECTED AT THE TAF SITES THIS AFTERNOON/TONIGHT. A SMALL CHANCE OF MIXED PRECIP AT THE TAF SITES THIS AFTERNOON AS YET ANOTHER WEAK SHORTWAVE PASSES...BUT MOISTURE APPEARS RATHER SHALLOW OR ANY PRECIP FALLING FROM CLOUDS AT OR ABOVE 700MB. LEFT ANY MENTION OF PRECIP THIS AFTERNOON OUT OF THE TAFS FOR NOW GIVEN THE LOWER CHANCES AND SOME UNCERTAINTY IF IT WILL OCCUR OR NOT. BIGGER CONCERN IS CONTINUED SATURATION OF THE BOUNDARY LAYER/LAYER BELOW THE INVERSION TONIGHT AND POTENTIAL FOR BR/FG AFTER MIDNIGHT. INTRODUCED SOME 2- 4SM BR TO THE TAF SITES AFTER 06Z-08Z. ONCE ANY BR/FG WOULD FORM...APPEARS IT COULD PERSIST WELL INTO THE DAY SAT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR WIZ017. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION.....04
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
958 AM MST FRI NOV 28 2014 .UPDATE... ISSUED AT 958 AM MST FRI NOV 28 2014 WESTERLY FLOW ALOFT WILL AGAIN BRING MILD AND DRY CONDITIONS TODAY. A FEW LOCATIONS IN THE FOOTHILLS ARE SEEING WIND GUSTS TO 70 MPH THIS MORNING. THE 12Z NAM INDICATES THE MOUNTAIN WAVE WILL DECREASE AROUND 18Z. EXPECT WINDS TO SLOW UP SOME WITH GUSTS DROPPING TO AROUND 40 MPH IN THESE WIND PRONE AREAS. WATER VAPOR SHOWING MOISTURE AT THE UPPER PARTS OF THE ATMOSPHERE WEST OF COLORADO TO THE PACIFIC. THIS WILL KEEP WAVE CLOUDS OVER EASTERN COLORADO TODAY AND TONIGHT. WILL KEEP HIGHS IN THE UPPER 60S TO LOWER 70S ACROSS NORTHEAST COLORADO. IF SKIES CONTINUE TO REMAIN NEARLY OVERCAST ACROSS NORTHEAST COLORADO MAY NEED TO LOWER TEMPERATURES A FEW DEGREES. && .SHORT TERM...(TODAY THROUGH TONIGHT ) ISSUED AT 414 AM MST FRI NOV 28 2014 WLY FLOW ALOFT WILL BE OVER THE RGN THRU TONIGHT. ONCE AGAIN HIGHER LEVEL MOISTURE IS EMBEDDED IN THE FLOW WHICH WILL LEAD TO SOME WAVE CLOUDS. SIMULATED IMAGERY SUGGESTS HI LVL CLOUD COVER THRU THE DAY SO ITS HARD TO SAY HOW MUCH OF AN IMPACT THIS WILL HAVE ON HIGHS. FOR NOW WILL KEEP READINGS IN THE UPPER 60S TO NR 70 AROUND DENVER WITH 60S ACROSS THE PLAINS. IF CLOUD COVER THINS OUT THEN RECORD HIGH OF 72 AT DENVER COULD BE TIED. AREAS ALONG THE PLATTE RIVER VALLEY FM FORT MORGAN TO STERLING MAY STAY IN THE UPPER 50S TO LOWER 60S IF THE HRRR IS CORRECT. AS FOR WINDS MTN TOP INVERSION IS RATHER WK THIS AFTN THRU TONIGHT SO APPEARS THE HIGHEST WINDS WILL STAY ABV TIMBERLINE WITH A FEW GUSTS IN THE 60 TO 70 MPH RANGE. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 414 AM MST FRI NOV 28 2014 STRONG WEST-SOUTHWESTERLY FLOW ALOFT WILL COVER THE FORECAST AREA INTO SUNDAY NIGHT. AN UPPER TROUGH WILL MOVE EASTWARD TO OUR NORTH SATURDAY NIGHT INTO MID DAY SUNDAY. UPWARD VERTICAL VELOCITY IS PROGGED FOR THE CWA SATURDAY INTO SUNDAY EVENING. THE BOUNDARY LAYER FLOW IS DOWNSLOPING SOUTHWESTERLIES ON SATURDAY AND SATURDAY NIGHT...WITH A COLD FRONT AND UPSLOPE FOR THE PLAINS AFTER 12Z SUNDAY MORNING. SOME FORM OF EASTERLY COMPONENT IS PROGGED THROUGH SUNDAY NIGHT FOR THE PLAINS AND FOOTHILLS. THE HIGHEST WINDS IN THE MOUNTAINS LOOK TO COME SATURDAY NIGHT...THE WAVE SET UP LOOKS THE STRONGEST THAN. NO HIGHLIGHTS. FOR MOISTURE...IT IS SPARSE SATURDAY AND SATURDAY NIGHT. THERE IS AN INCREASE FOR THE WESTERN CWA ON SUNDAY...BUT NOT A LOT IN THE LOWER LEVELS. THERE IS SOME LOW LEVEL MOISTURE OVER THE EASTERN HALF OF THE PLAINS WITH THE UPSLOPE BY SUNDAY AFTERNOON AND EVENING. MOISTURE IS BEST SUNDAY NIGHT...FAIRLY DEEP IN THE MOUNTAINS. MODELS SHOW A TAD OF MEASURABLE SNOWFALL ON THE QPF FIELDS FOR THE MOUNTAINS AND THE NORTHERN BORDER AREAS LATE SUNDAY AFTERNOON INTO EARLY MONDAY MORNING. WILL GO WITH SOME MINOR POPS IN THE MOUNTAINS SUNDAY NIGHT...THAT`S IT. SATURDAY`S HIGH TEMPERATURES ARE 1-2 C COOLER THAN THIS AFTERNOON`S HIGHS. ON SUNDAY...READINGS COOL DOWN SOME 10-20 C FROM WEST TO EAST. FOR THE LATER DAY`S...MONDAY THROUGH THURSDAY...THE ECMWF AND THE GFS HAVE COME MORE IN LINE WITH ONE ANOTHER. THERE IS ZONAL TO WEST-NORTHWESTERLY FLOW ALOFT ON MONDAY...THEN SOME UPPER RIDGING TUESDAY INTO WEDNESDAY...WITH THE ECMWF HAVING WEAK UPPER RIDGING ON WEDNESDAY. ON THURSDAY... THEY BOTH HAVE WEAK UPPER RIDGING. OVERALL THEY AGREE A BIT BETTER THAN YESTERDAY`S 00Z RUNS. THE GFS HAS MORE MOISTURE. WILL HAVE SOME MINOR ALPINE POPS HERE AND THERE BUT NOTHING SIGNIFICANT. && .AVIATION...(FOR THE TAFS THROUGH 18Z SATURDAY MORNING) ISSUED AT 958 AM MST FRI NOV 28 2014 VFR CONDITIONS WILL PREVAIL THROUGH THE NEXT 24 HOURS WITH HIGHS CLOUDS PERSISTING THROUGH TONIGHT AND INTO SATURDAY MORNING. SOUTHERLY WINDS THIS MORNING ARE EXPECTED TO TURN SOUTHWEST TO WEST AFTER 18Z. WINDS WILL RETURN SOUTHERLY THIS EVENING. && .BOU WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MEIER SHORT TERM...RPK LONG TERM...RJK AVIATION...MEIER
AREA FORECAST DISCUSSION
NWS ALBANY NY
603 PM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE REGION TONIGHT WITH COLD TEMPERATURES AND CLEARING SKIES. THE SURFACE HIGH WILL DRIFT OFF THE MID ATLANTIC COAST TOMORROW...AS A WARM FRONT WILL APPROACH FROM THE LOWER GREAT LAKES REGION AND PENNSYLVANIA SATURDAY NIGHT WITH A LIGHT MIX OF PRECIPITATION. MILDER WEATHER WILL RETURN FOR SUNDAY...AS TEMPERATURES MODERATE CLOSER TO NORMAL TO CLOSE OUT THE HOLIDAY WEEKEND. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 600 PM EST...DISORGANIZED LAKE EFFECT/ENHANCED SNOW SHOWERS AND FLURRIES CONTINUE IN THE W/NW FLOW ACROSS PARTS OF ERN NY AND WRN NEW ENGLAND. THE SCT SNOW SHOWERS ARE THE MOST NUMEROUS ON THE KENX RADAR FROM THE CAPITAL DISTRICT...MOHAWK VALLEY...SRN VERMONT THIS ACTIVITY WILL DIMINISH A BIT WITH THE LOSS OF THE DIURNAL HEATING. THE LATEST 3-KM HRRR SHOWS ANY LAKE EFFECT BAND LOSING ITS DOWNSTREAM EXTENSION INTO THE WRN MOHAWK VALLEY BTWN 00Z-03Z/SAT. THIS MAKES SENSE WITH THE LOWERING INVERSION...AND SFC ANTICYCLONE BUILDING IN. THE LOW-LEVEL FLOW WILL BACK AND BECOME MORE WESTERLY...SO THE BEST CHC OF AN INCH OR SO OF SNOW WILL BE IN THE WRN DACKS...PRIOR TO 06Z/SAT...AND THEN WE HAVE DIMINISHED POPS THEREAFTER. AS THE RIDGE BUILDS IN ACROSS THE MID ATLANTIC REGION...AND THE NORTHEAST...EXPECT THE SKIES TO BECOME CLEAR OR PARTLY CLOUDY. SOME RADIATIONAL COOLING IS EXPECTED WITH THE PARTIAL CLEARING WITH LIGHT TO CALM WINDS...AND A FAIRLY FRESH SNOW COVER. LOWS TEMPS WILL BE TRICKY...AS THE GFSMOS VALUES ARE ABOUT 10 TO 15 DEGREES COLDER THAN THE METMOS VALUES. WE HAVE GONE WITH A BLEND OF THE GUIDANCE VALUES...AND A SHADE CLOSER TO THE ECMWF MOS GUIDANCE. LOWS WILL BE IN THE TEENS FROM THE CAPITAL DISTRICT SOUTH...AND 5-10 DEGREES TO THE NORTH. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... SATURDAY...THE H500 FLOW BECOMES ZONAL...AS THE SFC HIGH BEGINS TO SHIFT OFF THE MID ATLANTIC COAST. A WARM FRONT WILL BE APPROACHING FROM THE GREAT LAKES REGION...AND OHIO VALLEY. MOST OF THE DAY SHOULD BE DRY WITH AN INCREASE OF MID AND HIGH CLOUDS DURING THE AFTERNOON. THE RETURN FLOW FROM THE SFC HIGH WILL HELP INCREASE THE WARM ADVECTION OVER THE FCST AREA...AS H850 TEMPS RISE TO -1C TO -4C BY 00Z/SUN. SOME SCT SNOW SHOWERS DUE TO THE INCREASING ISENTROPIC LIFT MAY MOVE INTO LOCATIONS NORTH AND WEST OF THE CAPITAL REGION BEFORE SUNSET. HIGHS WILL STILL BE ON THE COLD SIDE WITH HIGHS IN THE U20S TO M30S IN THE VALLEY AREAS...AND MAINLY 20S OVER THE HIGHER TERRAIN. SATURDAY NIGHT...TOUGH PART OF THE FCST WHERE LOW AND MID LEVEL WARMING WILL CONTINUE WITH THE WARM FRONT APPROACHING FROM PA...AND THE ERN GREAT LAKES REGION. CRITICAL PARTIAL THICKNESSES AND BUFKIT MODEL SOUNDINGS FOR KALB/KGFL/KPOU FROM THE NAM AND GFS INDICATE A VERY LIGHT WINTRY MIX OF SNOW TO SLEET/FREEZING RAIN IS POSSIBLE. THE STRONGEST QG FORCING FROM THE ISENTROPIC LIFT IS OVER THE NRN ZONES...ESPECIALLY NORTH OF THE CAPITAL REGION. WE HAVE PLACED A SLIGHT OR LOW CHC OF -FZRA AND/OR -IP IN THE FCST ESPECIALLY AFTER MIDNIGHT. THIS COULD BE A SITUATION WHERE A SPECIAL WX STATEMENT COULD HANDLE THE VERY LIGHT MIX...BUT WE WILL MENTION IT IN THE HWO WITH THE SLIGHT AND LOW CHC POPS. TEMPS WILL BE RISING...AND MODEL QPF FROM THE NAM/GFS/ECMWF/CANADIAN GUIDANCE IS GENERALLY 5 HUNDREDTHS OR LESS. A NON-DIURNAL TEMP TREND WAS USED IN THE FCST...AS DONE BY THE PREVIOUS SHIFT...WITH LOWS IN THE 20S TO L30S PRIOR TO MIDNIGHT. SUNDAY TO SUNDAY NIGHT...THE WARM FRONT LIFTS NORTH AND EAST OF THE REGION WITH ANY SPOTTY MIXED PCPN EARLY ON TRANSITIONING TO LIGHT RAIN SHOWERS OR DRIZZLE. SNOW MELT WILL LIKELY OCCUR...AS H850 TEMPS POP UP TO +3C TO +5C...AND SFC TEMPS ARE EXPECTED TO BE IN THE LOWER TO MID 40S WITH SOME U40S ACROSS WRN NEW ENGLAND...AND THE MID HUDSON VALLEY. A WEAK IMPULSE OR PREFRONTAL TROUGH AHEAD OF THE MAIN COLD FRONT MAY BRING ISOLD-SCT SHOWERS INTO THE FCST AREA LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT. CLOUDS SHOULD DOMINATE IN THE WARM SECTOR ON SUNDAY...AND THE BETTER CHC OF RAIN SHOWERS WILL SHORTLY BEFORE OR JUST AFTER MIDNIGHT...ESPECIALLY NORTH AND WEST OF THE CAPITAL DISTRICT. LOWS WILL BE IN THE MID AND U30S FOR MOST OF THE REGION SUNDAY NIGHT. && .LONG TERM /MONDAY THROUGH FRIDAY/... AT THE START OF THE EXTENDED PERIOD...A FRONTAL BOUNDARY WILL BE MOVING THROUGH THE REGION EARLY ON MONDAY. NOT THAT MUCH MOISTURE ASSOCIATED WITH THIS FRONT SO POPS HAVE ONLY BEEN FORECAST IN THE 30 TO 50 PERCENT CHANCE RANGE...WITH THE HIGHEST POPS OVER THE ADIRONDACKS. MUCH COLDER AIR BEHIND THIS FRONT...BUT MONDAY WILL STILL BE RELATIVELY MILD WITH HIGHS IN THE UPPER 30S AND 40S. THE COLDER AIR WILL DEFINITELY BE FELT MONDAY NIGHT WHEN TEMPS DROP TO LOWS IN THE TEENS TO MID 20S...AND THERE WILL BE ISOLATED SNOW SHOWERS. FAIR BUT COLD TUESDAY AND EARLY TUESDAY NIGHT AS A LARGE SURFACE HIGH MOVES ACROSS THE REGION. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED WITH HIGHS TUESDAY IN THE 20S TO LOWER 30S. LATER TUESDAY NIGHT CLOUDS WILL INCREASE AS ANOTHER FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST. THERE WILL ALSO BE A CHANCE OF SNOW LATE AT NIGHT. LOWS WILL BE IN THE UPPER TEENS AND 20S. THIS FRONTAL BOUNDARY WILL BE VERY SLOW TO MOVE SOUTH...SO THE CHANCE OF PCPN WILL LINGER INTO AT WEDNESDAY NIGHT. THE GFS EVEN SUGGEST THE FRONT WILL STALL OVER THE REGION WITH A PROLONGED PERIOD OF PCPN. HAVE FOLLOWED NCEP GUIDANCE FOR THE PERIOD THURSDAY THROUGH FRIDAY WITH A GENERALLY DRY FORECAST THURSDAY AND THURSDAY NIGHT... AND THEN A CHANCE OF PCPN AGAIN ON FRIDAY. MILDER AGAIN ON WEDNESDAY WITH HIGHS IN THE UPPER 30S AND 40S. LOWS WEDNESDAY NIGHT IN THE MID 20S TO LOWER 30S. A LITTLE COLDER THURSDAY AND FRIDAY WITH HIGHS IN THE 30S AND LOWER 40S. LOWS THURSDAY NIGHT 20 TO 30. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... MAINLY VFR CONDITIONS EXPECTED AT THE KGFL/KALB/KPOU/KPSF TAF SITES THROUGH THE TAF PERIOD ENDING AT 18Z SATURDAY AS A HIGH PRESSURE RIDGE MOVES ACROSS THE REGION DURING THE PERIOD. THE EXCEPTION WILL BE AT KPSF WHERE CIGS MAY OCCASIONALLY LOWER TO MVFR DURING THE REST OF THE AFTERNOON. SOME LAKE EFFECT MOISTURE...COLD TEMPS ALOFT AND DIURNAL HEATING COULD PRODUCE A -SHSN AT THE KGFL/KALB/KPSF TAF SITES SO HAVE INCLUDED VCSH AT THESE SITES INTO THE EVENING. MAINLY JUST SCT CLOUDS OVERNIGHT...WITH INCREASING MID LEVEL CLOUDINESS SATURDAY MORNING AS A WARM ADVECTION PATTERN TAKES HOLD. WINDS WILL BE WEST TO NORTHWEST WINDS AT 8 TO 12 KTS...WITH GUSTS OF AROUND 20 KTS AT KPSF/KALB THROUGH LATE THIS AFTERNOON. MAINLY LIGHT WINDS OVERNIGHT...GENERALLY LESS THAN 5 KTS. WINDS WILL SHIFT TO SOUTHERLY ON SATURDAY AT 5 TO 8 KTS. OUTLOOK... SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...FZRA...SLEET. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING WEDNESDAY. ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN AVERAGES AT A TENTH OF AN INCH OR LESS THE NEXT FEW DAYS. SNOWFALL ACCUMULATIONS WILL BE A COATING TO A FEW INCHES WITH THE HIGHER AMOUNTS DOWNWIND OF LAKE ONTARIO INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS. A WARM FRONT WILL BRING A LIGHT MIX OF PRECIPITATION SATURDAY NIGHT INTO EARLY SUNDAY MORNING. MILDER TEMPS ARE EXPECTED SUNDAY WITH SOME SNOW MELT. HOWEVER... TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH THE PASSAGE OF A STRONG COLD FRONT. ADDITIONAL QPF WILL BE LIGHT WITH A FEW HUNDREDTHS TO A TENTH OF AN INCH. 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...WASULA NEAR TERM...11/WASULA SHORT TERM...WASULA LONG TERM...GJM AVIATION...GJM HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
430 PM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE REGION TONIGHT WITH COLD TEMPERATURES AND CLEARING SKIES. THE SURFACE HIGH WILL DRIFT OFF THE MID ATLANTIC COAST TOMORROW...AS A WARM FRONT WILL APPROACH FROM THE LOWER GREAT LAKES REGION AND PENNSYLVANIA SATURDAY NIGHT WITH A LIGHT MIX OF PRECIPITATION. MILDER WEATHER WILL RETURN FOR SUNDAY...AS TEMPERATURES MODERATE CLOSER TO NORMAL TO CLOSE OUT THE HOLIDAY WEEKEND. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 430 PM EST...DISORGANIZED LAKE EFFECT/ENHANCED SNOW SHOWERS AND FLURRIES CONTINUE IN THE W/NW FLOW ACROSS PARTS OF ER NY AND WRN NEW ENGLAND. THE SCT SNOW SHOWERS ARE THE MOST NUMEROUS ON THE KENX RADAR FROM THE CAPITAL DISTRICT...MOHAWK VALLEY...NRN BERKSHIRES NORTHWARD. THIS ACTIVITY WILL DIMINISH A BIT WITH THE LOSS OF THE DIURNAL HEATING. THE LATEST 3-KM HRRR SHOWS ANY LAKE EFFECT BAND LOSING ITS DOWNSTREAM EXTENSION INTO THE WRN MOHAWK VALLEY BTWN 00Z-03Z/SAT. THIS MAKES SENSES WITH THE LOWERING INVERSION...AND SFC ANTICYCLONE BUILDING IN. THE LOW-LEVEL FLOW WILL BACK AND BECOME MORE WESTERLY...SO THE BEST CHC OF AN INCH OR SO OF SNOW WILL BE IN THE WRN DACKS...PRIOR TO 06Z/SAT...AND THEN WE HAVE DIMINISHED POPS THEREAFTER. AS THE RIDGE BUILDS IN ACROSS THE MID ATLANTIC REGION...AND THE NORTHEAST...EXPECT THE SKIES TO BECOME CLEAR OR PARTLY CLOUDY. SOME RADIATIONAL COOLING IS EXPECTED WITH THE PARTIAL CLEARING WITH LIGHT TO CALM WINDS...AND A FAIRLY FRESH SNOW COVER. LOWS TEMPS WILL BE TRICKY...AS THE GFSMOS VALUES ARE ABOUT 10 TO 15 DEGREES COLDER THAN THE METMOS VALUES. WE HAVE GONE WITH A BLEND OF THE GUIDANCE VALUES...AND A SHADE CLOSER TO THE ECMWF MOS GUIDANCE. LOWS WILL BE IN THE TEENS FROM THE CAPITAL DISTRICT SOUTH...AND 5-10 DEGREES TO THE NORTH. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... SATURDAY...THE H500 FLOW BECOMES ZONAL...AS THE SFC HIGH BEGINS TO SHIFT OFF THE MID ATLANTIC COAST. A WARM FRONT WILL BE APPROACHING FROM THE GREAT LAKES REGION...AND OHIO VALLEY. MOST OF THE DAY SHOULD BE DRY WITH AN INCREASE OF MID AND HIGH CLOUDS DURING THE AFTERNOON. THE RETURN FLOW FROM THE SFC HIGH WILL HELP INCREASE THE WARM ADVECTION OVER THE FCST AREA...AS H850 TEMPS RISE TO -1C TO -4C BY 00Z/SUN. SOME SCT SNOW SHOWERS DUE TO THE INCREASING ISENTROPIC LIFT MAY MOVE INTO LOCATIONS NORTH AND WEST OF THE CAPITAL REGION BEFORE SUNSET. HIGHS WILL STILL BE ON THE COLD SIDE WITH HIGHS IN THE U20S TO M30S IN THE VALLEY AREAS...AND MAINLY 20S OVER THE HIGHER TERRAIN. SATURDAY NIGHT...TOUGH PART OF THE FCST WHERE LOW AND MID LEVEL WARMING WILL CONTINUE WITH THE WARM FRONT APPROACHING FROM PA...AND THE ERN GREAT LAKES REGION. CRITICAL PARTIAL THICKNESSES AND BUFKIT MODEL SOUNDINGS FOR KALB/KGFL/KPOU FROM THE NAM AND GFS INDICATE A VERY LIGHT WINTRY MIX OF SNOW TO SLEET/FREEZING RAIN IS POSSIBLE. THE STRONGEST QG FORCING FROM THE ISENTROPIC LIFT IS OVER THE NRN ZONES...ESPECIALLY NORTH OF THE CAPITAL REGION. WE HAVE PLACED A SLIGHT OR LOW CHC OF -FZRA AND/OR -IP IN THE FCST ESPECIALLY AFTER MIDNIGHT. THIS COULD BE A SITUATION WHERE A SPECIAL WX STATEMENT COULD HANDLE THE VERY LIGHT MIX...BUT WE WILL MENTION IT IN THE HWO WITH THE SLIGHT AND LOW CHC POPS. TEMPS WILL BE RISING...AND MODEL QPF FROM THE NAM/GFS/ECMWF/CANADIAN GUIDANCE IS GENERALLY 5 HUNDREDTHS OR LESS. A NON-DIURNAL TEMP TREND WAS USED IN THE FCST...AS DONE BY THE PREVIOUS SHIFT...WITH LOWS IN THE 20S TO L30S PRIOR TO MIDNIGHT. SUNDAY TO SUNDAY NIGHT...THE WARM FRONT LIFTS NORTH AND EAST OF THE REGION WITH ANY SPOTTY MIXED PCPN EARLY ON TRANSITIONING TO LIGHT RAIN SHOWERS OR DRIZZLE. SNOW MELT WILL LIKELY OCCUR...AS H850 TEMPS POP UP TO +3C TO +5C...AND SFC TEMPS ARE EXPECTED TO BE IN THE LOWER TO MID 40S WITH SOME U40S ACROSS WRN NEW ENGLAND...AND THE MID HUDSON VALLEY. A WEAK IMPULSE OR PREFRONTAL TROUGH AHEAD OF THE MAIN COLD FRONT MAY BRING ISOLD-SCT SHOWERS INTO THE FCST AREA LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT. CLOUDS SHOULD DOMINATE IN THE WARM SECTOR ON SUNDAY...AND THE BETTER CHC OF RAIN SHOWERS WILL SHORTLY BEFORE OR JUST AFTER MIDNIGHT...ESPECIALLY NORTH AND WEST OF THE CAPITAL DISTRICT. LOWS WILL BE IN THE MID AND U30S FOR MOST OF THE REGION SUNDAY NIGHT. && .LONG TERM /MONDAY THROUGH FRIDAY/... AT THE START OF THE EXTENDED PERIOD...A FRONTAL BOUNDARY WILL BE MOVING THROUGH THE REGION EARLY ON MONDAY. NOT THAT MUCH MOISTURE ASSOCIATED WITH THIS FRONT SO POPS HAVE ONLY BEEN FORECAST IN THE 30 TO 50 PERCENT CHANCE RANGE...WITH THE HIGHEST POPS OVER THE ADIRONDACKS. MUCH COLDER AIR BEHIND THIS FRONT...BUT MONDAY WILL STILL BE RELATIVELY MILD WITH HIGHS IN THE UPPER 30S AND 40S. THE COLDER AIR WILL DEFINITELY BE FELT MONDAY NIGHT WHEN TEMPS DROP TO LOWS IN THE TEENS TO MID 20S...AND THERE WILL BE ISOLATED SNOW SHOWERS. FAIR BUT COLD TUESDAY AND EARLY TUESDAY NIGHT AS A LARGE SURFACE HIGH MOVES ACROSS THE REGION. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED WITH HIGHS TUESDAY IN THE 20S TO LOWER 30S. LATER TUESDAY NIGHT CLOUDS WILL INCREASE AS ANOTHER FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST. THERE WILL ALSO BE A CHANCE OF SNOW LATE AT NIGHT. LOWS WILL BE IN THE UPPER TEENS AND 20S. THIS FRONTAL BOUNDARY WILL BE VERY SLOW TO MOVE SOUTH...SO THE CHANCE OF PCPN WILL LINGER INTO AT WEDNESDAY NIGHT. THE GFS EVEN SUGGEST THE FRONT WILL STALL OVER THE REGION WITH A PROLONGED PERIOD OF PCPN. HAVE FOLLOWED NCEP GUIDANCE FOR THE PERIOD THURSDAY THROUGH FRIDAY WITH A GENERALLY DRY FORECAST THURSDAY AND THURSDAY NIGHT... AND THEN A CHANCE OF PCPN AGAIN ON FRIDAY. MILDER AGAIN ON WEDNESDAY WITH HIGHS IN THE UPPER 30S AND 40S. LOWS WEDNESDAY NIGHT IN THE MID 20S TO LOWER 30S. A LITTLE COLDER THURSDAY AND FRIDAY WITH HIGHS IN THE 30S AND LOWER 40S. LOWS THURSDAY NIGHT 20 TO 30. && .AVIATION /22Z FRIDAY THROUGH WEDNESDAY/... MAINLY VFR CONDITIONS EXPECTED AT THE KGFL/KALB/KPOU/KPSF TAF SITES THROUGHT HE TAF PERIOD ENDING AT 18Z SATURDAY AS A HIGH PRESSURE RIDGE MOVES ACROSS THE REGION DURING THE PERIOD. THE EXCEPTION WILL BE AT KPSF WHERE CIGS MAY OCCASIONALLY LOWER TO MVFR DURING THE REST OF THE AFTERNOON. SOME LAKE EFFECT MOISTURE...COLD TEMPS ALOFT AND DIURNAL HEATING COULD PRODUCE A -SHSN AT THE KGFL/KALB/KPSF TAF SITES SO HAVE INCLUDED VCSH AT THESE SITES INTO THE EEVENING. MAINLY JUST SCT CLOUDS OVERNIGHT...WITH INCREASING MID LEVEL CLOUDINESS SATURDAY MORNING AS A WARM ADVECTION PATTERN TAKES HOLD. WINDS WILL BE WEST TO NORTHWEST WINDS AT 8 TO 12 KTS...WITH GUSTS OF AROUND 20 KTS AT KPSF/KALB THROUGH LATE THIS AFTERNOON. MAINLY LIGHT WINDS OVERNIGHT...GENERALLY LESS THAN 5 KTS. WINDS WILL SHIFT TO SOUTHERLY ON SATURDAY AT 5 TO 8 KTS. OUTLOOK... SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...FZRA...SLEET. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING WEDNESDAY. ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN AVERAGES AT A TENTH OF AN INCH OR LESS THE NEXT FEW DAYS. SNOWFALL ACCUMULATIONS WILL BE A COATING TO A FEW INCHES WITH THE HIGHER AMOUNTS DOWNWIND OF LAKE ONTARIO INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS. A WARM FRONT WILL BRING A LIGHT MIX OF PRECIPITATION SATURDAY NIGHT INTO EARLY SUNDAY MORNING. MILDER TEMPS ARE EXPECTED SUNDAY WITH SOME SNOW MELT. HOWEVER... TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH THE PASSAGE OF A STRONG COLD FRONT. ADDITIONAL QPF WILL BE LIGHT WITH A FEW HUNDREDTHS TO A TENTH OF AN INCH. 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...WASULA NEAR TERM...WASULA SHORT TERM...WASULA LONG TERM...GJM AVIATION...GJM HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS ALBANY NY
429 PM EST FRI NOV 28 2014 .SYNOPSIS... HIGH PRESSURE WILL BRIEFLY RIDGE INTO THE REGION TONIGHT WITH COLD TEMPERATURES AND CLEARING SKIES. THE SURFACE HIGH WILL DRIFT OFF THE MID ATLANTIC COAST TOMORROW...AS A WARM FRONT WILL APPROACH FROM THE LOWER GREAT LAKES REGION AND PENNSYLVANIA SATURDAY NIGHT WITH A LIGHT MIX OF PRECIPITATION. MILDER WEATHER WILL RETURN FOR SUNDAY...AS TEMPERATURES MODERATE CLOSER TO NORMAL TO CLOSE OUT THE HOLIDAY WEEKEND. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... AS OF 428 PM EST...DISORGANIZED LAKE EFFECT/ENHANCED SNOW SHOWERS AND FLURRIES CONTINUE IN THE W/NW FLOW ACROSS PARTS OF ER NY AND WRN NEW ENGLAND. THE SCT SNOW SHOWERS ARE THE MOST NUMEROUS ON THE KENX RADAR FROM THE CAPITAL DISTRICT...MOHAWK VALLEY...NRN BERKSHIRES NORTHWARD. THIS ACTIVITY WILL DIMINISH A BIT WITH THE LOSS OF THE DIURNAL HEATING. THE LATEST 3-KM HRRR SHOWS ANY LAKE EFFECT BAND LOSING ITS DOWNSTREAM EXTENSION INTO THE WRN MOHAWK VALLEY BTWN 00Z-03Z/SAT. THIS MAKES SENSES WITH THE LOWERING INVERSION...AND SFC ANTICYCLONE BUILDING IN. THE LOW-LEVEL FLOW WILL BACK AND BECOME MORE WESTERLY...SO THE BEST CHC OF AN INCH OR SO OF SNOW WILL BE IN THE WRN DACKS...PRIOR TO 06Z/SAT...AND THEN WE HAVE DIMINISHED POPS THEREAFTER. AS THE RIDGE BUILDS IN ACROSS THE MID ATLANTIC REGION...AND THE NORTHEAST...EXPECT THE SKIES TO BECOME CLEAR OR PARTLY CLOUDY. SOME RADIATIONAL COOLING IS EXPECTED WITH THE PARTIAL CLEARING WITH LIGHT TO CALM WINDS...AND A FAIRLY FRESH SNOW COVER. LOWS TEMPS WILL BE TRICKY...AS THE GFSMOS VALUES ARE ABOUT 10 TO 15 DEGREES COLDER THAN THE METMOS VALUES. WE HAVE GONE WITH A BLEND OF THE GUIDANCE VALUES...AND A SHADE CLOSER TO THE ECMWF MOS GUIDANCE. LOWS WILL BE IN THE TEENS FROM THE CAPITAL DISTRICT SOUTH...AND 5-10 DEGREES TO THE NORTH. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... SATURDAY...THE H500 FLOW BECOMES ZONAL...AS THE SFC HIGH BEGINS TO SHIFT OFF THE MID ATLANTIC COAST. A WARM FRONT WILL BE APPROACHING FROM THE GREAT LAKES REGION...AND OHIO VALLEY. MOST OF THE DAY SHOULD BE DRY WITH AN INCREASE OF MID AND HIGH CLOUDS DURING THE AFTERNOON. THE RETURN FLOW FROM THE SFC HIGH WILL HELP INCREASE THE WARM ADVECTION OVER THE FCST AREA...AS H850 TEMPS RISE TO -1C TO -4C BY 00Z/SUN. SOME SCT SNOW SHOWERS DUE TO THE INCREASING ISENTROPIC LIFT MAY MOVE INTO LOCATIONS NORTH AND WEST OF THE CAPITAL REGION BEFORE SUNSET. HIGHS WILL STILL BE ON THE COLD SIDE WITH HIGHS IN THE U20S TO M30S IN THE VALLEY AREAS...AND MAINLY 20S OVER THE HIGHER TERRAIN. SATURDAY NIGHT...TOUGH PART OF THE FCST WHERE LOW AND MID LEVEL WARMING WILL CONTINUE WITH THE WARM FRONT APPROACHING FROM PA...AND THE ERN GREAT LAKES REGION. CRITICAL PARTIAL THICKNESSES AND BUFKIT MODEL SOUNDINGS FOR KALB/KGFL/KPOU FROM THE NAM AND GFS INDICATE A VERY LIGHT WINTRY MIX OF SNOW TO SLEET/FREEZING RAIN IS POSSIBLE. THE STRONGEST QG FORCING FROM THE ISENTROPIC LIFT IS OVER THE NRN ZONES...ESPECIALLY NORTH OF THE CAPITAL REGION. WE HAVE PLACED A SLIGHT OR LOW CHC OF -FZRA AND/OR -IP IN THE FCST ESPECIALLY AFTER MIDNIGHT. THIS COULD BE A SITUATION WHERE A SPECIAL WX STATEMENT COULD HANDLE THE VERY LIGHT MIX...BUT WE WILL MENTION IT IN THE HWO WITH THE SLIGHT AND LOW CHC POPS. TEMPS WILL BE RISING...AND MODEL QPF FROM THE NAM/GFS/ECMWF/CANADIAN GUIDANCE IS GENERALLY 5 HUNDREDTHS OR LESS. A NON-DIURNAL TEMP TREND WAS USED IN THE FCST...AS DONE BY THE PREVIOUS SHIFT...WITH LOWS IN THE 20S TO L30S PRIOR TO MIDNIGHT. SUNDAY TO SUNDAY NIGHT...THE WARM FRONT LIFTS NORTH AND EAST OF THE REGION WITH ANY SPOTTY MIXED PCPN EARLY ON TRANSITIONING TO LIGHT RAIN SHOWERS OR DRIZZLE. SNOW MELT WILL LIKELY OCCUR...AS H850 TEMPS POP UP TO +3C TO +5C...AND SFC TEMPS ARE EXPECTED TO BE IN THE LOWER TO MID 40S WITH SOME U40S ACROSS WRN NEW ENGLAND...AND THE MID HUDSON VALLEY. A WEAK IMPULSE OR PREFRONTAL TROUGH AHEAD OF THE MAIN COLD FRONT MAY BRING ISOLD-SCT SHOWERS INTO THE FCST AREA LATE SUNDAY AFTERNOON INTO SUNDAY NIGHT. CLOUDS SHOULD DOMINATE IN THE WARM SECTOR ON SUNDAY...AND THE BETTER CHC OF RAIN SHOWERS WILL SHORTLY BEFORE OR JUST AFTER MIDNIGHT...ESPECIALLY NORTH AND WEST OF THE CAPITAL DISTRICT. LOWS WILL BE IN THE MID AND U30S FOR MOST OF THE REGION SUNDAY NIGHT. && .LONG TERM /MONDAY THROUGH FRIDAY/... AT THE START OF THE EXTENDED PERIOD...A FRONTAL BOUNDARY WILL BE MOVING THROUGH THE REGION EARLY ON MONDAY. NOT THAT MUCH MOISTURE ASSOCIATED WITH THIS FRONT SO POPS HAVE ONLY BEEN FORECAST IN THE 30 TO 50 PERCENT CHANCE RANGE...WITH THE HIGHEST POPS OVER THE ADIRONDACKS. MUCH COLDER AIR BEHIND THIS FRONT...BUT MONDAY WILL STILL BE RELATIVELY MILD WITH HIGHS IN THE UPPER 30S AND 40S. THE COLDER AIR WILL DEFINITELY BE FELT MONDAY NIGHT WHEN TEMPS DROP TO LOWS IN THE TEENS TO MID 20S...AND THERE WILL BE ISOLATED SNOW SHOWERS. FAIR BUT COLD TUESDAY AND EARLY TUESDAY NIGHT AS A LARGE SURFACE HIGH MOVES ACROSS THE REGION. MAINLY CLEAR TO PARTLY CLOUDY SKIES EXPECTED WITH HIGHS TUESDAY IN THE 20S TO LOWER 30S. LATER TUESDAY NIGHT CLOUDS WILL INCREASE AS ANOTHER FRONTAL BOUNDARY APPROACHES FROM THE NORTHWEST. THERE WILL ALSO BE A CHANCE OF SNOW LATE AT NIGHT. LOWS WILL BE IN THE UPPER TEENS AND 20S. THIS FRONTAL BOUNDARY WILL BE VERY SLOW TO MOVE SOUTH...SO THE CHANCE OF PCPN WILL LINGER INTO AT WEDNESDAY NIGHT. THE GFS EVEN SUGGEST THE FRONT WILL STALL OVER THE REGION WITH A PROLONGED PERIOD OF PCPN. HAVE FOLLOWED NCEP GUIDANCE FOR THE PERIOD THURSDAY THROUGH FRIDAY WITH A GENERALLY DRY FORECAST THURSDAY AND THURSDAY NIGHT... AND THEN A CHANCE OF PCPN AGAIN ON FRIDAY. MILDER AGAIN ON WEDNESDAY WITH HIGHS IN THE UPPER 30S AND 40S. LOWS WEDNESDAY NIGHT IN THE MID 20S TO LOWER 30S. A LITTLE COLDER THURSDAY AND FRIDAY WITH HIGHS IN THE 30S AND LOWER 40S. LOWS THURSDAY NIGHT 20 TO 30. && .AVIATION /21Z FRIDAY THROUGH WEDNESDAY/... MAINLY VFR CONDITIONS EXPECTED AT THE KGFL/KALB/KPOU/KPSF TAF SITES THROUGHT HE TAF PERIOD ENDING AT 18Z SATURDAY AS A HIGH PRESSURE RIDGE MOVES ACROSS THE REGION DURING THE PERIOD. THE EXCEPTION WILL BE AT KPSF WHERE CIGS MAY OCCASIONALLY LOWER TO MVFR DURING THE REST OF THE AFTERNOON. SOME LAKE EFFECT MOISTURE...COLD TEMPS ALOFT AND DIURNAL HEATING COULD PRODUCE A -SHSN AT THE KGFL/KALB/KPSF TAF SITES SO HAVE INCLUDED VCSH AT THESE SITES INTO THE EEVENING. MAINLY JUST SCT CLOUDS OVERNIGHT...WITH INCREASING MID LEVEL CLOUDINESS SATURDAY MORNING AS A WARM ADVECTION PATTERN TAKES HOLD. WINDS WILL BE WEST TO NORTHWEST WINDS AT 8 TO 12 KTS...WITH GUSTS OF AROUND 20 KTS AT KPSF/KALB THROUGH LATE THIS AFTERNOON. MAINLY LIGHT WINDS OVERNIGHT...GENERALLY LESS THAN 5 KTS. WINDS WILL SHIFT TO SOUTHERLY ON SATURDAY AT 5 TO 8 KTS. OUTLOOK... SATURDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN...FZRA...SLEET. SUNDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHRA. SUNDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA. MONDAY NIGHT: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SHSN. TUESDAY: NO OPERATIONAL IMPACT. NO SIG WX. TUESDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. WEDNESDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHRA...SHSN. && .HYDROLOGY... NO SIGNIFICANT HYDROLOGIC PROBLEMS ARE EXPECTED THE NEXT 5 DAYS ENDING WEDNESDAY. ADDITIONAL LIGHT PRECIPITATION AMOUNTS ARE EXPECTED WITH BASIN AVERAGES AT A TENTH OF AN INCH OR LESS THE NEXT FEW DAYS. SNOWFALL ACCUMULATIONS WILL BE A COATING TO A FEW INCHES WITH THE HIGHER AMOUNTS DOWNWIND OF LAKE ONTARIO INTO PORTIONS OF THE WESTERN MOHAWK VALLEY AND WESTERN ADIRONDACKS. A WARM FRONT WILL BRING A LIGHT MIX OD PRECIPITATION SATURDAY NIGHT INTO EARLY SUNDAY MORNING. MILDER TEMPS ARE EXPECTED SUNDAY WITH SOME SNOW MELT. HOWEVER... TEMPERATURES ARE EXPECTED TO COOL OFF QUICKLY DURING MONDAY WITH THE PASSAGE OF A STRONG COLD FRONT. ADDITIONAL QPF WILL BE LIGHT WITH A FEW HUNDREDTHS TO A TENTH OF AN INCH. 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...WASULA NEAR TERM...WASULA SHORT TERM...WASULA LONG TERM...GJM AVIATION...GJM HYDROLOGY...BGM/WASULA
AREA FORECAST DISCUSSION
NWS QUAD CITIES IA IL
319 PM CST FRI NOV 28 2014 .SYNOPSIS... ISSUED AT 318 PM CST FRI NOV 28 2014 NEARLY ZONAL FLOW ALOFT AND H85 WAA IS AIDING TO ADVECT A WARM FRONT INTO THE AREA TODAY. TEMPERATURES RANGE FROM THE LOWER TO MID 40S ACROSS THE SOUTHERN CWA...AND TO THE MID AND LOWER 30S ACROSS THE NORTHERN CWA. SATELLITE IMAGERY IS SHOWING THE SNOW PACK MELTING WITH THIS WAA. DEWPOINTS ARE RISING INTO THE UPPER 20S TO LOW 30S. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 318 PM CST FRI NOV 28 2014 MAIN FORECAST CONCERN FOR THE SHORT TERM FORECAST IS THE WARM FRONT MOVING INTO THE AREA TONIGHT BRINGING WITH IT A CHANCE OF FOG AND POSSIBLY LOW LEVEL CLOUDS. IT IS CLEAR THAT THE MODELS...ESPECIALLY THE NAM DO NOT HAVE A GOOD HANDLE ON BOUNDARY LAYER MOISTURE. THE NAM OVER DOES THE CURRENT SNOW COVER. WITH STRONG H85 WAA THE NAM POPS LOW LEVEL CLOUDS TONIGHT AND THROUGH MOST OF THE DAY. THE GFS HAS SOMETHING SIMILAR...BUT NOT AS BULLISH. A LOOK AT THE MODEL FIELDS AND OBSERVATIONS LEADS ME TO BELIEVE THAT THERE IS NOT A GOOD CHANCE FOR THE DEVELOPMENT OF LOW LEVEL CLOUDS...THERE IS NOT ENOUGH DEEP LAYER MOISTURE OR FORCING FOR CLOUD DEVELOPMENT. BELIEVE THAT THE MAIN THREAT WILL BE FOG DUE TO OVERRUNNING WARM AIR OVER A MELTING SNOW PACK. WINDS ARE FORECAST TO REMAIN AROUND 8-10KTS TONIGHT WHICH MAY INHIBIT FOG DEVELOPMENT. THIS WIND WILL MAKE FOG DEVELOPMENT PATCHY TONIGHT . HIGH LEVEL CLOUDS SHOULD CONTINUE TO ADVECT THROUGH THE AREA...ALSO INHIBITING THE DEVELOPMENT OF FOG OVER A LARGE AREA. SATURDAY LOOKS TO BE WARM WITH TEMPERATURES IN THE MID 40S TO LOW 50S SOUTH. DID NOT USE ANY OF THE NAM GUIDANCE FOR TEMP FORECASTS AS THE NAM KEEPS SNOW PACK AROUND A THUS LOWERS TEMPS. HIGH TEMPERATURES TODAY WERE UNDER DOWN AS H85 WAA DROVE TEMPS HIGHER. THE RUC HAD THE BEST HANDLE ON HIGHS AND TRENDS WITH TEMPS TODAY. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 318 PM CST FRI NOV 28 2014 SATURDAY NIGHT...COLD FRONT TO ARRIVE NORTHWEST CWA TOWARD DAYBREAK. PATCHY FOG POSSIBLE AHEAD OF FRONT BUT WITH AMERICAN MODELS VERIFYING TOO MOIST OVER BL AND ENOUGH OF GRADIENT PRE-FRONTAL FOR 5-10+ MPH WINDS AND TYPICALLY NOT FAVORED VEERING SOUTHWESTERLY DIRECTION I HAVE LEFT OUT ANY MENTION ATTIM. DECENT TEMP GRADIENT BY 12Z SUN WITH 20S FAR NORTHWEST CWA POST-FRONTAL CONTRAST TO UPPER 30S AND LOWER 40S FAR SOUTHEAST CWA. SUNDAY AND SUNDAY NIGHT...HIGHS ON SUNDAY TO OCCUR IN THE AM THROUGH MIDDAY AHEAD OF FRONTAL PASSAGE. FRONT IS ANTICIPATED TO BE EXITING FAR EAST/SOUTHEAST CWA BY MIDDAY. ENSUING COLD ADVECTION ON BRISK NORTHWEST WINDS 15 TO 30 MPH WILL RESULT IN FALLING TEMPS DESPITE DECREASING CLOUDS FOR AT LEAST PARTIAL PM SUNSHINE. SUNDAY NIGHT...CONTINUED CLEARING EARLY WITH CANADIAN HIGH AND ATTENDANT STRONG SUBSIDENCE BUILDING IN. LINGERING PRESSURE GRADIENT TO MAINTAIN ENOUGH WIND TO PREVENT COMPLETE BOTTOM OUT ON LOWS AND WITH LOSS OF SNOW COVER LEANED TOWARD WARMER SIDE OF GUIDANCE BLEND...WITH MAINLY TEENS FOR LOWS WITH SOME SINGLE DIGITS NORTHWEST CWA. THESE TEMPS COMBINED WITH WINDS WILL PRODUCE BITTER COLD WIND CHILLS IN SINGLE DIGITS ABOVE AND BELOW ZERO OVERNIGHT INTO EARLY MONDAY MORNING. MONDAY AND MONDAY NIGHT...DRY AND CONTINUED COLD WITH WELL BELOW NORMAL TEMPS AS CANADIAN HIGH BUILDS IN. HIGHS MONDAY IN THE TEENS AND 20S. LOWS MONDAY NIGHT IN SINGLE DIGITS TO AROUND 10 DEGS. IF ANY LONGER DURATION OF LIGHT OR CALM WINDS THEN LOWS MAY BE STILL 2-4 DEGS TOO WARM SOME LOCATIONS. TUESDAY AND TUESDAY NIGHT...CANADIAN HIGH WILL SHIFT EAST INTO THE OHIO VLY DURING THE DAY ON TUESDAY WITH STRENGTHENING RETURN FLOW USHERING IN WARMER AIR FOR REBOUND ON TEMPS INTO THE 30S FOR HIGHS MANY AREAS. CONTINUED SOUTHERLY WINDS TO KEEP LOWS MAINLY IN THE 20S TUESDAY NIGHT. WEDNESDAY THROUGH FRIDAY...MEDIUM RANGE MODELS SUPPORT A LIGHT PCPN EVENT AS EJECTING ENERGY FROM ROCKIES MEETS UP WITH INCREASING MOISTURE. CHALLENGE THOUGH IS MODELS CONTINUE TO VARY ON THE TIMING/PLACEMENT OF SURFACE AND UPPER FEATURES AND AS RESULT INSTEAD OF PLACING HIGHER POPS FOR WHAT IS LIKELY TO BE ONLY 12 HOUR EVENT AT BEST... HAVE PLACED SMALL POPS OVER 24+ HOUR PERIOD FOCUSING ON THURSDAY AND THURSDAY NIGHT ATTIM. PCPN TYPE APPEARS TO BE MAINLY RAIN BUT DEPENDING ON TIMING COULD BEGIN AS LIGHT WINTRY MIX IN SOME AREAS. TEMPS WILL CONTINUE MODERATING TO CLOSER TO NORMAL DURING THE PERIOD. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1144 AM CST FRI NOV 28 2014 MAIN CONCERN FOR AVIATION COULD BE THE DEVELOPMENT OF FG OR BR TONIGHT INTO TOMORROW AM. SNOW MELT COULD LEAD TO SOME VSBY RESTRICTIONS...ESPECIALLY AT BRL. CONFIDENCE IS LOW IN THE DEVELOPMENT OF ANYTHING LESS THAN MVFR...HOWEVER GUIDANCE SUGGESTS LIFR FOR A LARGE AREA. BELIEVE THAT GUIDANCE IS DOING A POOR JOB WITH LOW LEVEL MOISTURE SO WILL ONLY GO MVFR AT BRL AND VFR ELSEWHERE. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...NONE. IL...NONE. MO...NONE. && $$ SYNOPSIS...GIBBS SHORT TERM...GIBBS LONG TERM...05 AVIATION...GIBBS
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1216 PM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CST FRI NOV 28 2014 MAIN CONCERN IN THE SHORT TERM IS THE POTENTIAL FOR FREEZING RAIN OR SLEET LATER TODAY AS A WEAK DISTURBANCE MOVES ALONG THE MINNESOTA RIVER VALLEY. MEANWHILE TEMPERATURES WILL MODERATE INTO THE 20S TODAY...AND REMAIN THEIR OVERNIGHT. A BAND OF LIGHT TO MODERATE SNOW TIED TO THE H850-H700 WARM AIR ADVECTION MOVED ACROSS THE NORTHERN HALF OF THE FORECAST AREA OVERNIGHT AND PRODUCED ROUGHLY 1 TO 2 INCHES OF SNOW. BY EARLY FRIDAY MORNING THIS BAND WAS LOCATED ACROSS EASTERN MN WESTERN WI...AND AS A RESULT DROPPED THE UPSTREAM COUNTIES FROM THE WINTER WEATHER ADVISORY. LATER TODAY ANOTHER WEAK SHORTWAVE WILL SLIDE ACROSS THE REGION. THIS SEEMS TO BE HANDLED BEST BY THE LAST FEW RUNS OF THE RAP13. THE CONCERN WITH THIS FEATURE IS THE POTENTIAL FOR PRECIP FALLING THROUGH A WARM LAYER WHICH BY 18Z IS FORECAST TO BE +3C AT KMSP AND EVEN WARMER AT POINTS SOUTHWARD. THE SURFACE WILL STILL BE IN THE 20S...SO THIS WOULD LEAD TO A BRIEF PERIOD OF SLEET/FREEZING RAIN ROUGHLY ALONG A LINE JUST SOUTH OF THE I-94 CORRIDOR...REACHING EAU CLAIRE BY LATE AFTERNOON. ACCUMULATIONS WOULD ONLY BE 1 OR 2 HUNDREDTHS...BUT EVEN THOSE MEAGER AMOUNTS COULD LEAD TO SLICK ROADWAYS. FOR NOW INCREASED THE POPS AND TRENDED TOWARDS THE LAST FEW RUNS OF THE HOPWRF AND HRRR WHICH HAVE SLOWED THE ONSET OF THIS PRECIP. ONCE THIS MOVES THROUGH H850 AIR OF +5 TO +7 WILL REMAIN IN PLACE OVERNIGHT...AS SOUTHEASTERLY WINDS GRADUALLY VEER TO A SOUTHERLY DIRECTION BY SATURDAY MORNING. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 357 AM CST FRI NOV 28 2014 STRONG WARM AIR ADVECTION WILL BE THE PREVAILING STORY SATURDAY WITH A WMFNT WELL N OF THE WFO MPX CWFA AND AN INCOMING ARCTIC HIGH PRES AIRMASS THAT LOOKS TO DROP THE HAMMER ON TEMPERATURES GOING INTO SUNDAY. NOT LOOKING FOR MUCH OF ANYTHING IN TERMS OF PRECIPITATION SO SATURDAY WILL RESULT IN MOSTLY CLOUDY SKIES DUE TO INCREASED MOISTURE PROMOTING STRATUS DEVELOPMENT OVER A DECENT SNOWPACK AND FAIRLY WIDESPREAD NVA KEEPING PRECIP N OF THE AREA. DESPITE THE CLOUD COVER...THE STRONG WAA WILL FORCE HIGHS INTO THE UPR 30S AND EVEN LWR 40S. BY LATE EVENING...A POTENT CDFNT WILL DROP THRU THE CWFA...WHICH WILL HELP SCOUR OUT SOME OF THE CLOUD COVER BUT IS NOT XPCTD TO PRODUCE MUCH...IF ANY...PRECIP FOR THE CWFA. WINDS WILL KICK UP BUT THE MAIN EFFECT WILL BE TO SIGNIFICANTLY DROP TEMPERATURES FOR SUNDAY...WITH HIGHS ONLY REACHING THE LWR TEENS TO LWR 20S. THE ARCTIC HIGH PRES AIRMASS WILL PERSIST THRU MON...PRODUCING HIGHS ONLY IN THE SINGLE DIGITS ABOVE ZERO DESPITE PLENTY OF SUNSHINE. AS THE HIGH PRES AREA SHIFTS OFF TO THE E FOR THE MIDDLE PORTION OF NEXT WEEK...A MORE SOUTHERLY FLOW ON THE BACKSIDE WILL ALLOW SOME MODERATION IN TEMPERATURES BUT STILL BELOW THE FREEZING MARK. HIGHS WILL CLIMB INTO THE 20S...WITH VERY LITTLE CHANCES OF PRECIP GOING THROUGH THE WEEK. THERE ARE STILL SOME INDICATIONS OF A MORE ORGANIZED LOW PRES SYSTEM MOVING THRU THE CENTRAL CONUS MID-TO-LATE NEXT WEEK BUT MODEL CONSENSUS...AND HENCE FORECAST CONFIDENCE...REMAINS LOW IN THIS THINKING SO HAVE KEPT MUCH OF THE AREA DRY THRU NEXT WEEK. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1148 AM CST FRI NOV 28 2014 PRIMARY CONCERN IS THE NEXT 6 HOURS DEALING WITH FREEZING DRIZZLE POTENTIAL ACROSS THE AREA. LOW CONFIDENCE IN THE FORECAST OVERALL..ESPECIALLY TONIGHT AND TOMORROW MORNING. THE NAM HAS OVERDONE ITS MOISTURE ANALYSIS AND IS AFFECTING ITS PROFILES THROUGH TONIGHT. STARTING OFF...A BATCH OF MOSTLY FREEZING DRIZZLE/RAIN IS MOVING WEST TO EAST ACROSS THE FA EARLY THIS AFTERNOON. THANKFULLY...THE REFLECTIVITY RETURNS CURRENTLY ON RADAR SHOW A DECENT AMOUNT OF VIRGA IN SOME SPOTS...ESPECIALLY FAR SOUTHERN MN. IN ADDITION...THE PRECIP THAT IS REACHING THE GROUND WILL NOT LAST VERY LONG...SO AMOUNTS SHOULD BE VERY LIGHT. THIS AREA WILL CONTINUE WORKING EAST ACROSS THE AREA. IN TERMS OF CLOUD COVER AND FOG POTENTIAL...I QUESTION NAM SOUNDING MOISTURE SIMILAR TO THE PREVIOUS SHIFT. CONSIDERING THE SUITE OF GUIDANCE AT HAND HOWEVER...ITS CLEAR THAT LOW LEVEL SOUTHWESTERLY FLOW WILL CONTINUE TO USHER IN WARMER AND DRIER AIR TO THE FA. THE BIG QUESTION IS WHAT HAPPENS NEAR THE SURFACE AS THE INVERSION STRENGTHENS. CURRENT FORECAST CALLS FOR ENOUGH MOISTURE TRAPPING TO ALLOW MVFR OR IFR CIGS TO REMAIN IN PLACE. HRRR INDICATES LOW STRATUS BECOMING TRAPPED UNDER THE DRYING OCCURRING ABOVE 900-850H...SO INDICATED THE POTENTIAL FOR RESTRICTIONS THROUGH MUCH OF TOMORROW. KMSP...THIS IS AN EVOLVING FORECAST SITUATION. BOUTS OF FZDZ APPEAR MORE LIKELY FROM 19-21Z HAS AS BEEN OBSERVED UPSTREAM OF MSP. OTHERWISE...WE CONTINUE TO LINGER ON THE EDGE OF VFR TO THE WEST. STILL...EXPECTING THE CIGS TO PERSIST THROUGH THE AFTERNOON. CONFIDENCE IN THE CEILING FORECAST BEYOND 00Z IS QUITE LOW. SOUTHWESTERLY DRY AIR ADVECTION COULD PREVENT RESTRICTIONS TONIGHT...BUT WENT WITH A MORE PESSIMISTIC FORECAST BECAUSE THE STRENGTH OF THE INVERSION LENDS ME TO BELIEVE WE`LL GET ENOUGH MOISTURE TRAPPED BELOW IT TO CAUSE PROBLEMS. /OUTLOOK FOR KMSP/ SUN NIGHT...VFR. WINDS NW AT 15G25KTS. MON...VFR. WINDS NW AT 5-10KTS...BECOMING S LATE. TUE...VFR. WINDS S AT 15G20KTS...BECOMING W. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. && $$ SHORT TERM...JRB LONG TERM...JPC AVIATION...SPD
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1149 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 358 AM CST FRI NOV 28 2014 TODAY AND TONIGHT...A CHECK ON UPPER LEVEL MOISTURE IN THE NAM...GFS AND RAP MODELS INDICATES AN INCREASE TODAY. UPPER LEVEL WINDS ALSO INCREASE BY 10 TO 15 KT. THIS WOULD SUGGEST THE POTENTIAL FOR CIRRUS DEVELOPING OFF THE LARAMIE RANGE WHICH WOULD SPREAD EAST DURING THE AFTN. THE AMOUNT OF COVERAGE RANGES FROM TOTALLY OVERCAST IN THE GFS TO NEARLY NONE IN THE RAP. THE TEMPERATURE FORECAST USES A MIDDLE OF THE ROAD APPROACH FOR PARTLY CLOUDY CONDITIONS. THE RAP AND NAM ALSO SHOW A WEAK COLD FRONT DROPPING THROUGH NRN NEBRASKA THIS AFTN WHICH WOULD KEEP THE NORTH MOSTLY IN THE 50S FOR HIGHS. SOUTH OF THE FRONT...DESPITE THE HIGH CLOUDS...DEEPER MIXING IS EXPECTED WHICH SHOULD SEND HIGHS INTO THE 60S TO LOWER 70S...NEAR RECORD. TONIGHT...THE MODELS SHOW THE UPPER LEVELS DRYING OUT WHICH WOULD BE ALL FOR CLEARING...LIGHT WINDS AND RADIATIONAL COOLING THE IN THE N/S PLATTE VALLEYS. THE HIGHLANDS STAY MIXED. LOWS TONIGHT RANGE FROM THE LOWER 20S IN THE VALLEYS TO UPPER 30S ACROSS THE SANDHILLS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 358 AM CST FRI NOV 28 2014 FORECAST CONCERNS DEAL WITH TEMPERATURES AND WINDS...AND FIRE WEATHER POTENTIAL FOR SATURDAY. THE NEXT WEEK LOOKS LARGELY DRY ALTHOUGH IT IS POSSIBLE FOR A FEW SNOW SHOWERS /FLURRIES/ WITH LITTLE OR NO ACCUMULATION SATURDAY NIGHT INTO MONDAY MORNING. MODELS HAVE DECENT AGREEMENT THROUGH THE PERIOD NOW SO CONFIDENCE IS IMPROVING WITH THE SENSIBLE WEATHER CONDITIONS FOR THIS FORECAST CYCLE. THE PERIOD BEGINS WITH A VERY ANOMALOUSLY WARM DAY FOR SATURDAY. VERY LITTLE RUN TO RUN CHANGES HAVE BEEN NOTICED ACROSS THE AREA SO GOOD CONFIDENCE ON A VERY WARM DAY. THE IMPENDING STRONG COLD FRONT WILL STAY UP OVER SOUTH DAKOTA THROUGH 00Z SUNDAY WITH THE SURFACE PATTERN SHOWING WESTERLY WINDS ACROSS NEBRASKA. THE WESTERLY COMPONENT OF THE WINDS WILL GIVE THE AIR IN THE BOUNDARY LAYER WARMING DOWNSLOPE CONDITIONS. THE MODELS AREN/T PARTICULARLY STRONG WITH THE WINDS AS THE PRESSURE GRADIENT IS QUITE WEAK BUT DEEPER MIXING INTO THE AFTERNOON SHOULD PROVIDE BREEZY CONDITIONS IN PLACES. THE STRONGER WINDS AT THE TOP OF THE MIXED LAYER ARE ACROSS NORTHERN NEBRASKA AT 20 TO 30KTS. GOING SOUTH...THE SOUTHERN PART OF THE STATE SEES WINDS AT THE SAME LEVEL ONLY AT 10 TO 15KTS. HAVE INCLUDED THE HIGHER WINDS OVER THE NORTHERN AREAS AND LOWER WINDS ACROSS THE SOUTH IN THE FORECAST TODAY. LOOKING INTO HIGHS...MINIMAL CHANGES WERE MADE TO ONGOING FORECAST. THIS LEAVES HIGHS IN THE 60S...WITH LOW 70S OVER THE SOUTHERN PART OF THE STATE. STANDARDIZED ANOMALIES CONTINUE TO SHOW TEMPERATURES AT 850MB AT 2-3 STANDARD DEVIATIONS ABOVE NORMAL. THINKING THIS WILL BE CLOSE TO THE HEIGHT OF THE MIXED LAYER...LIKELY HIGHER OVER THE HIGHER TERRAIN IN THE WESTERN PART OF THE FORECAST AREA SO AGAIN...ONGOING TEMPERATURES LOOK APPROPRIATE WHICH WILL BE NEAR RECORD READINGS. THE OTHER CONCERN WITH SATURDAY WILL BE NEAR CRITICAL FIRE WEATHER POTENTIAL. THE WARM TEMPERATURES AND DRY AIR IN PLACE WILL DROP RELATIVE HUMIDITY DOWN BELOW 20 PERCENT...MAINLY FROM SOUTHWEST NEBRASKA INTO THE EASTERN SANDHILLS. AT THIS TIME...THE STRONGER WINDS DON/T LOOK TO COINCIDE WITH THE DRIER CONDITIONS SO NOT ANTICIPATING THE NEED FOR FIRE WEATHER HEADLINES DESPITE THE WARM AND DRY CONDITIONS. THE COLD FRONT WILL PLOW SOUTH THROUGH THE FORECAST AREA SATURDAY NIGHT. THIS FRONT WILL DROP TEMPERATURES DRAMATICALLY WITH 850MB VALUES LOWERING FROM 13-18C AT 00Z SUNDAY TO -17C TO -10C BY 00Z MONDAY. THIS WILL KEEP THE DIURNAL TEMPERATURE CHANGE VERY MINIMAL ON SUNDAY AND TEMPERATURES WILL ONLY RAISE INTO THE 20S FOR MUCH OF THE AREA. ALSO THINKING WINDS WILL INCREASE BEHIND THE FRONT AND HAVE TRENDED THE FORECAST ACCORDINGLY FOR SATURDAY NIGHT AND SUNDAY. NEARLY UNIDIRECTIONAL WINDS FROM THE NORTH- NORTHWEST...STRONG COLD AIR ADVECTION...GOOD SUBSIDENCE...AND A TIGHT PRESSURE GRADIENT ALL ARE GOOD INGREDIENTS FOR BREEZY TO STRONG WINDS. THE MODELS ARE INDICATING SOME FRONTOGENETICAL FORCING ALONG THE FRONT SATURDAY NIGHT. MOISTURE ISN/T VERY IMPRESSIVE AND REALLY NOT MUCH LIFT IN THE LAYER SO JUST ADDED IN SOME FLURRIES FOR NOW IN AREAS. THEN...ON SUNDAY NIGHT AS THE SURFACE HIGH BUILDS SOUTHEAST INTO EASTER SOUTH DAKOTA RETURN FLOW WILL BE IN PLACE FROM WESTERN KANSAS INTO THE NEBRASKA PANHANDLE. THIS WILL BRING SOME INCREASED MOISTURE INTO LEVELS BELOW 700MB. ALTHOUGH THE MOISTURE DOES INCREASE...THE LIFT IN THE LAYER ISN/T VERY IMPRESSIVE SO DIDN/T HAVE THE CONFIDENCE TO ADD MEASURABLE SNOW IN THE FORECAST YET AND JUST INCLUDED SOME FLURRIES FOR PORTIONS OF THE PANHANDLE SUNDAY NIGHT. MONDAY MORNING WILL BE QUITE COLD AS THE REGION IS INFLUENCED BY THE COLD AIR /850MB TEMPERATURES AT -12C TO -14C AND A SURFACE HIGH CENTERED OVER THE DAKOTAS. THE AIRMASS IN PLACE WOULD SUGGEST LOWS BELOW ZERO ARE CERTAINLY POSSIBLE WHERE WINDS DECOUPLE COMPLETELY AND BECOME CALM. THIS MAY STAY IN AREAS DIRECTLY UNDER THE SURFACE HIGH OVER SOUTH DAKOTA SO KEPT LOWS IN THE SINGLE DIGITS AT THIS TIME THOUGH DID DROP THEM A FEW DEGREES. THE NEXT WORK WEEK LOOKS TO BE A YO-YO IN TEMPERATURES WITH COLD CONDITIONS MONDAY AND WEDNESDAY AND A BIT WARMER FOR TUESDAY AND THURSDAY. THE HIGH DEPARTS MONDAY NIGHT WITH FAIRLY STRONG RETURN FLOW OCCURRING INTO TUESDAY TO PUSH OUT THE COLD AIR MASS WITH A RETURN OF CLOSE TO NEAR NORMAL TEMPERATURES IN THE 40S MOST PLACES. ANOTHER COLD FRONT WILL THEN MOVE THROUGH THE NORTHERN PLAINS AGAIN TUESDAY NIGHT AND MODELS HAVE COME INTO BETTER AGREEMENT IN ITS TIMING AND OTHER DETAILS. THIS FRONTAL PASSAGE LOOKS TO BE DRY AT THIS TIME BUT IT WILL BRING ANOTHER REINFORCING SHOT OF COLDER AIR...ALTHOUGH NOT NEARLY AS COLD AS THE SUNDAY SYSTEM. THEN THURSDAY LOOKS TO BRING STRONG WARM AIR ADVECTION BACK TO PERHAPS GET TEMPERATURES BACK ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1120 AM CST FRI NOV 28 2014 SCATTERED TO BROKEN HIGH CLOUDINESS WILL CONTINUE TO STREAM EAST ACROSS THE REGION THIS AFTERNOON INTO TONIGHT. VFR CONDITIONS WILL PREVAIL WITH WEST WINDS 5 TO 15 KTS. LOCAL GUSTS TO 25 KTS ARE POSSIBLE THIS AFTERNOON ACROSS NORTHERN NEBRASKA. && .FIRE WEATHER... ISSUED AT 317 AM CST FRI NOV 28 2014 TODAY...DEWPOINTS WHERE DERIVED FROM 50 PERCENT OF THE VERY DRY RAP MODEL AND 50 PERCENT OF THE OTHER MODELS. THIS PRODUCES RH VALUES BETWEEN 15 AND 20 PERCENT SOUTH OF INTERSTATE 80. WINDS SHOULD BE LIGHT IN THIS AREA AS THE RAP SHOWS A SFC TROF SETTING UP ACROSS THE SOUTH. SO VERY HIGH FIRE DANGER IS EXPECTED BUT WINDS ARE LIGHT GUSTING TO JUST 20 MPH. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...CDC LONG TERM...BROOKS AVIATION...TAYLOR FIRE WEATHER...CDC
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1244 PM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 1243 PM CST FRI NOV 28 2014 A FEW MINOR TWEAKS FOR CURRENT RADAR TRENDS...BUT OTHERWISE NO MAJOR CHANGES FOR THIS UPDATE. UPDATE ISSUED AT 946 AM CST FRI NOV 28 2014 THERE HAVE BEEN SOME REPORTS OF SLEET AND FREEZING RAIN IN A FEW SPOTS IN OUR SOUTHWESTERN COUNTIES...WHICH IS SUPPORTED BY BUFKIT SOUNDINGS. GIVEN THE SCATTERED NATURE OF THE FREEZING RAIN/SLEET SHOWERS AND THE FACT THAT THE SHORT TERM MODELS HAVE THIS ACTIVITY DISSIPATING IN THE NEXT HOUR OR SO WILL KEEP ANY HEADLINES OUT FOR NOW AND JUST GO WITH A NOWCAST. HOWEVER WILL KEEP AN EYE ON THINGS IN CASE THE ACTIVITY PERSISTS LONGER THAN EXPECTED. UPDATE ISSUED AT 706 AM CST FRI NOV 28 2014 WILL MAINTAIN A SCATTERED TYPE POP THIS MORNING OVER THE FCST AREA. RADAR HAS BEEN SHOWING SOME VERY LIGHT SNOW MOVING INTO DVL BASIN-LANGDON AREAS. OF MORE INTEREST IS CONVECTIVE SHOWERS THAT WERE IN EASTERN MT EARLIER THEY ARE MOVING QUICKLY TOWARD LISBON- VALLEY CITY AND WILL MOVE INTO FARGO AREA. COVERAGE HAS DIMINISHED A TAD....BUT PTYPE IS WHAT IS MOST IMPORTANT. BUFKIT SOUNDINGS WOULD INDICATE SLEET PSBL IN JAMESTOWN BUT THEN MORE OF A SNOW SOUNDING FARTHER EAST AS DEPTH OF COLD AIR IS QUITE DEEP AS YOU MOVE EAST. FOR NOW WILL MAINTAIN PREV PTYPE GRIDS WHICH IS SNOW FOR VALLEY CITY-FARGO AND SOME SLEET/SNOW IN FORMAN/GWINNER AREA. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 MODELS HAVE IN GENERAL HANDLED THINGS VERY POORLY LATELY. WHAT WAS GOING TO BE A DECENT SNOW CLIPPERY SYSTEM LAST NIGHT WAS ANYTHING BUT. BAROCLINIC ZONE REMAINED WELL SOUTH AND WEST OF WHAT WAS PROGGED 24 HOURS AGO AND THUS MAIN 1 TO 2 INCH BAND WAS FROM MINOT AREA TO JAMESTOWN TO ALEXANDRIA MN INSTEAD OF BEING FARTHER NORTH. AMOUNTS WEAKER AS WELL AS FOCUS OF WARM ADVECTION AND LIFT SEEMED MORE CONFINED TO ERN SD/WCNTRL MN JUST OUTSIDE OF MAIN PRECIP BAND. ANYHOW FIRST PRECIP BAND OF LIGHT SNOW EASTERN MN INTO WISCONSIN. THERE IS A LARGER AREA OF LIGHT SNOW UPSTREAM IN SASKATCHEWAN INTO SW MANITOBA AND TRYING TO SPREAD INTO NCNTRL ND. LATEST RAP/NAM SEEM OK IN SHOWING THIS LIGHT SNOW SPREADING INTO NRN VALLEY AND PARTS OF NW MN THIS MORNING BEFORE DRYING UP. THERE IS AN AREA OF CONVECTIVE SHOWERS THAT FORMED IN ECNTRL MONTANTA AND IS NOW NORTHWEST OF BISMARCK. RAP HAS SOME PRECIP SURVIVING AND MOVING INTO PARTS OF ECNTRL OR SE ND 12Z-15Z PERIOD. SO WITH CHANCES OF LIGHT SNOW NORTH AND SOUTH KEPT PRETTY BROAD POPS THRU 18Z FRI. TOP DOWN DID SHOW SOME RISK OF SLEET IN FAR SOUTHEASTERN ND IF PRECIP REACHES THAT AREA. THIS AFTN PRETTY QUIET MOST AREAS...THOUGH LINGERING LIGHT SNOW CHANCES FAR NORTH. BUT MAIN 850 MB WARM ADVECTION RETURNS BACK TO CENTRAL SASKATCHEWAN THIS AFTN AHEAD OF SHROT WAVE AND SFC LOW IN SOUTHERN B.C. THIS SYSTEM TO MOVE INTO NORTH CENTRAL ND SATURDAY MORNING WITH MAIN AREA OF WARM ADV SNOWS NORTH OF THE INTL BORDER. THOUGH DID KEEP SOME POPS IN NRN FCST AREA AS SRN EDGE MAY IMPACT AREAS ALONG THE BORDER. QUITE WARM AIR BUILDS INTO THE SOUTHERN HALF OF THE FCST AREA LATER TONIGHT INTO SATURDAY SO HIGHS TODAY WILL BE NEAR LOWS TONIGHT IN MANY AREAS AND THEN RISING TO SOME LOWER OR MID 30S IN THE FAR SOUTH SATURDAY WITH SOUTH WINDS WHILE NORTH WINDS RETURN TO DVL BASIN AND FAR NRN VALLEY AS LOW MOVES EAST. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 322 AM CST FRI NOV 28 2014 LOW WILL MOVE EAST THRU NRN MN WITH COLD FRONT MOVING SOUTH THRU THE FCST AREA. SOME LIGHT SNOW WITH FRONT BUT NOTHING MUCH. VERY COLD AIRMASS MOVES IN SUNDAY WITH HIGHS LIKELY STAYING BELOW ZERO IN FAR NORTHERN ND. HIGH PRESSURE MOVES IN SUN NIGHT INTO CNTRL ND WITH CLEAR SKY AND DID GO A BIT LOWER THAN SUPERBLEND BASED ON WED NIGHTS LOWS. SUSPECT -20S AGAIN IN THE DVL BASIN. MONDAY TO THURSDAY...OVERALL DRY AND COLD AS THE PERIOD BEGINS WITH SFC HIGH PRESSURE CENTERED OVER THE NORTHERN PLAINS AND AN ARCTIC AIRMASS IN PLACE. THE NEXT SHORT WAVE MOVES ACROSS THE INTERNATIONAL BORDER ON MONDAY NIGHT INTO TUESDAY ALLOWING FOR WEAK AND BRIEF RIDGING SCOURING OUT THE WELL BELOW NORMAL COLD AIRMASS. NW FLOW IN THE WAKE OF THIS SHORT WAVE IS NOT AS AMPLIFIED...RESULTING IN A LESS COLD AIRMASS...WITH 850MB TEMPS IN THE 10 TO 18 BELOW RANGE FOR WEDNESDAY. ZONAL FLOW APPEARS TO DEVELOP UP THURSDAY WITH TEMPS REBOUNDING INTO THE 20S. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1243 PM CST FRI NOV 28 2014 ABUNDANT MOISTURE AND WEAK FORCING YIELDING AREAS OF IFR/MVFR CIGS/VSBY THIS MORNING. SHALLOW LOW LEVEL BOUNDARY FORECAST TO SHIFT SLOWLY NORTH THROUGH00Z. LOW RISK -FRDZ/PL NEAR THE BOUNDARY WHERE MOISTURE AND LIFT ARE MAXIMIZED. ALTHOUGH THIS BOUNDARY SHOULD LIFT NORTH DURING THIS PERIOD EXPECT SLOW IMPROVEMENT KDVL-KGFK-KBJI LINE. SOUTH OF BOUNDARY VSBY SHOULD SHOW GRDL IMPROVEMENT AND DECREASE -SN/PL/-FRDZ RISK. OBS AND LAMP GUIDANCE SUGGEST VFR AFTER WEAK BOUNDARY LIFT PAST TAF SITE. HOWEVER TIMING IS VERY PROBLEMATIC AS BOUNDARY WILL BE SLOW TO MOVE NORTH. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...NONE. MN...NONE. && $$ UPDATE...JR SHORT TERM...RIDDLE LONG TERM...JK/RIDDLE AVIATION...EWENS
AREA FORECAST DISCUSSION
NWS SIOUX FALLS SD
254 PM CST FRI NOV 28 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 231 PM CST FRI NOV 28 2014 MAIN QUESTION TONIGHT IS FOG POTENTIAL OR NOT. THE NAM AND RAP CONTINUE TO SHOW A LOT OF FOG DEVELOPMENT THROUGHOUT MUCH OF NORTHWEST IA...SOUTHWEST MN...PARTS OF SOUTHEAST SD AND EAST CENTRAL SD. THEY BEGIN THE FOG DEVELOPMENT THIS EVENING ACROSS FAR NORTHWEST IA...THEN EXPAND IT WEST AND NORTHWARD. THE NAM AND RAP ARE VERY MOIST WITH THEIR RESPECTIVE SURFACE DEW POINT DEPRESSIONS...IN FACT SHOWING A LOT OF 1 TO 2 DEGREE DEW POINT DEPRESSION SPREADS EVEN AT THIS TIME WHICH IS NOT VERIFYING. THE GFS...ECMWF AND ARW ARE MUCH MORE SUBDUED...SHOWING WIDER DEW POINT DEPRESSIONS AND THUS LESS FOG. FOR NOW...KEPT AREAS OF FOG GOING FROM THE BROOKINGS AREA SOUTHEASTWARD THROUGH OUR EASTERN ZONES. THIS MATCHES UP WITH THE SMALL DEW POINT DEPRESSIONS ADVERTISED BY THE ECMWF IN THOSE AREAS...WITH PATCHY FOG FOR ADJACENT AREAS TO THE WEST...NOT BUYING THE NAM OR RAP OUTPUT. LATE TONIGHT A WELL DEFINED WARM FRONT BEGINS TO NUDGE EASTWARD HELPING TO ACTUALLY WARM TEMPERATURES ACROSS THIS AREA. THIS MAY ALSO HELP IN REDUCING FOG POTENTIAL...AT LEAST WEST OF I 29. FOR TEMPERATURES...LOADED UP THE CHILLY GEM BIAS CORRECTED VALUES FROM SOUTHWEST MN THROUGH THE IA GREAT LAKES REGION...WITH A LOT OF ECMWF ELSEWHERE. SATURDAY SHOULD BE A WARM DAY AHEAD OF THE NEXT CANADIAN FRONT... WHICH WILL MAKE ITS PRESENCE FELT IN OUR NORTHERN ZONES BY AFTERNOON. THEREFORE LOOKING AT SLOWLY FALLING TEMPERATURES NORTH OF I 90 DURING THE AFTERNOON...BUT WITH READINGS STILL FAIRLY MILD. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 231 PM CST FRI NOV 28 2014 IN THE MEDIUM TO LONG RANGE...PATTERN BEGINS TO SHIFT EARLY IN THE WORK WEEK AS WE TRANSITION TO A MOSTLY WESTERLY ZONAL FLOW WHICH WILL EVENTUALLY MODERATE TEMPERATURES TO NEAR NORMAL READINGS. ON SATURDAY NIGHT ANOTHER SHOT OF COLD AIR WILL MOVE INTO THE AREA BEHIND A COLD FRONT WITH LOWS FROM THE SINGLE DIGITS NORTH OF I-90 TO THE TEENS ELSEWHERE. THERE IS THE POTENTIAL FOR FLURRIES ALONG AND JUST BEHIND THE FRONT SO HAVE KEPT IN CHANCE FOR THAT TIME. SURFACE HIGH PRESSURE BUILDS IN AND WILL CONTINUE TO DRAG COLD AIR IN WITH THE COLDEST AIR OVER US ON SUNDAY NIGHT. EXPECT LOWS ON SUN NIGHT TO BE IN THE SINGLE DIGITS WITH SOME AREAS...ESPECIALLY NORTH...SEEING TEMPS AROUND -3 TO -4. VERY COLD TEMPS COMBINED WITH 5-10 MPH WIND WILL RESULT IN WIND CHILL VALUES OF -10 TO -20 RIGHT AROUND THE MORNING COMMUTE. NOT MUCH OF A REBOUND IN TEMPS EXPECED ON MONDAY WITH HIGHS IN THE TEENS TO LOW 20S. FOR TUESDAY TO FRIDAY...NO SENSIBLE WEATHER TO SPEAK OF AS ZONAL FLOW DOMINATES. TEMPS WILL CONTINUE TO INCH TOWARD MORE SEASONABLE READINGS BY THURS/FRI. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1137 AM CST FRI NOV 28 2014 VFR WILL CERTAINLY PREVAIL TODAY. THERE IS MORE OF A QUESTION MARK TONIGHT. THERE ARE STILL SOME INDICATIONS LOOKING AT THE VARIOUS SHORT RANGE ENSEMBLES THAT LOW CEILINGS AND VISIBILITIES WILL FIRST SETUP OVER EXTREME NORTHWEST IA AFTER SUNSET...THEN WORK NORTH AND NORTHWEST POTENTIALLY AFFECTING THE KFSD TAF SITE. CURRENTLY EXTREME NORTHWEST IA AND SOUTHWEST MN DO EXHIBIT SMALL SURFACE DEW POINT DEPRESSIONS...SO THIS SCENARIO IS PLAUSIBLE. THERE IS A QUESTION HOWEVER...BECAUSE IT IS PRIMARILY THE NAM AND RAP WHICH ARE SHOWING THIS...WHILE MANY OF THE OTHER MODELS ARE NOT. SO ENOUGH UNCERTAINTY EXISTS THAT WE STILL DO NOT WANT TO GO ALL IN FOR FOG AND LOW CEILINGS FOR KFSD. IT APPEARS THAT KSUX WILL BE TOO FAR WEST IF THIS SCENARIO WERE TO PAN OUT...AND THAT KHON MAY BE MORE IMPACTED BY JUST THE USUAL MVFR LATE NIGHT LIGHT FOG WITH A SOUTHERLY FLOW. KEPT KSUX VFR...AND KFSD MVFR FOR NOW FOR TONIGHT. && .FSD WATCHES/WARNINGS/ADVISORIES... SD...NONE. MN...NONE. IA...NONE. NE...NONE. && $$ SHORT TERM...MJ LONG TERM...SALLY AVIATION...MJ
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
450 PM CST FRI NOV 28 2014 .UPDATE... ISSUED AT 450 PM CST FRI NOV 28 2014 SCATTERED FREEZING RAIN SHOWERS CONTINUE ALONG AND NORTH OF INTERSTATE 90 WITH SOME LOCAL LAW ENFORCEMENT AGENCIES STARTING TO REPORT SOME SLIC ROADS AND ACCIDENTS. LOOKING AT THE LATEST HRRR...THIS SHOULD CONTINUE INTO THE EARLY EVENING BEFORE PUSHING OFF TO THE EAST AND OPTED TO ISSUE A FREEZING RAIN ADVISORY WITH SOME ICING STARTING TO OCCUR AND TO RAISE THE AWARENESS. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 AT 3 PM...A BAND OF MODERATE TO STRONG 700 TO 500 MB FRONTOGENESIS WAS STARTING TO MOVE EAST INTO WEST CENTRAL WISCONSIN. THIS BAND HAS PRODUCED AREAS OF FREEZING RAIN AND OCCASIONALLY SOME ICE PELLETS ACROSS SOUTHEAST MINNESOTA. PERIODIC CHECKS WITH LAW ENFORCEMENT AND SPOTTERS HAVE NOT INDICATED TOO MUCH OF AN IMPACT FROM IT. IT JUST STARTED HERE AT THE OFFICE AND IT IS FREEZING ON THE VEHICLES AND SLICK SPOTS ON UNTREATED SIDEWALKS. HAVE TO ISSUE A SPECIAL WEATHER STATEMENT FOR AREAS ALONG AND NORTH OF INTERSTATE 90 TO COVER THE POTENTIAL FOR LIGHT ICING ON UNTREATED SURFACES. FOR THIS EVENING...THE 28.18Z RAP AND NAM SHOW THAT THIS BAND WILL CONTINUE TO MOVE EAST ACROSS WEST CENTRAL...CENTRAL...AND NORTH CENTRAL WISCONSIN. AS IT MOVES INTO NORTH CENTRAL WISCONSIN... SOUNDINGS SUGGEST THAT THERE MAY BE A BRIEF PERIOD OF SNOW MIXING IN WITH THIS WINTRY MIX. SOME OF THE MESO MODELS SUGGEST UP TO A TENTH OF AN INCH OF QPF. THIS SEEMS TO BE A BIT ON THE HIGH SIDE CONSIDERING THE DRY AIR BETWEEN 700 TO 850 MB...SO HAVE LIQUID AMOUNTS OF 0.01 TO 0.03 INCHES. FOR OVERNIGHT...EXPECT THE WINTRY PRECIPITATION TO BE IN CLARK AND TAYLOR COUNTIES...AND THEN MOVE OUT BY 3 AM. THERE MAY BE SOME VERY LIGHT ICING. STRONG WARM AIR ADVECTION WILL CAUSE RISING TEMPERATURES THROUGH THE NIGHT. TEMPERATURES WILL RISE FROM THE LOWER TO MID 20S INTO THE MID AND UPPER 20S BY MORNING. AS THIS WARM AIR MOVES OVER THE SNOW PACK...THERE MAY BE SOME AREAS OF FOG. ON SATURDAY...THE TEMPERATURE FORECAST IS PROBLEMATIC DUE TO THE SNOW COVER. THE NAM SNOW COVER IS INITIALIZED TOO HIGH. IT HAS SNOW DEPTHS OF 4 TO 8 INCHES. WE ARE ACTUALLY MORE IN THE TRACE TO 4 INCHES...SO SOME OF THE WARMING IN THE MODELS IS GOING TO SNOW MELT INSTEAD OF WARMING THE AIR MASS NEAR THE GROUND. THE WARMEST 925 AND 850 MB TEMPERATURES ARE LOCATED ALONG AND SOUTH OF INTERSTATE 90. 925 MB TEMPERATURES WILL CLIMB TO 0 TO 8C INTO THESE AREAS...SO A BIT CONCERNED THAT THE TEMPERATURES COULD WARM A BIT WARMER THAN THE LOW TO MID 40S THAT ARE CURRENTLY FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 ON SATURDAY NIGHT AND SUNDAY MORNING...THE FIRST OF 2 ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. 850 MB TEMPERATURES FALL FROM 6 TO 10C INTO -7 TO -15C. THE STRONG COLD AIR ADVECTION WILL CAUSE TEMPERATURES TO SLOWLY FALL THROUGH MUCH OF THE DAY. WAS INITIALLY CONCERNED ABOUT STRONG WINDS ADVECTING TO THE SURFACE DUE TO STRONG SUBSIDENCE IN THE WAKE OF THIS FRONT. HOWEVER SOUNDINGS CONTINUE TO SHOW THAT THE WINDS WILL STAY MAINLY IN THE 15 TO 25 MPH. THIS WILL PRODUCE WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. ON SUNDAY NIGHT...ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA. THIS WILL LOWER 850 MB TEMPERATURES DOWN INTO THE -15C TO -19C FOR MONDAY MORNING BEFORE WARM AIR ADVECTION STARTS TO DEVELOP ACROSS THE AREA DURING THE AFTERNOON AND MONDAY NIGHT. HIGH TEMPERATURES ON MONDAY WILL RANGE FROM 5 TO 15 DEGREES. LIGHTER WINDS WILL KEEP WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. FROM THURSDAY INTO THURSDAY NIGHT...THE MODELS CONTINUE TO STRUGGLE WITH WHETHER A LOW PRESSURE SYSTEM WILL BRING PRECIPITATION TO THE AREA. THE GFS AND ECMWF ARE NOW SIMILAR WITH THE TRACK THROUGH THE MID MISSISSIPPI RIVER VALLEY AND WESTERN GREAT LAKES. HOWEVER THEY ARE 12 HOUR APART. PRECIPITATION TYPE WILL BE SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1110 AM CST FRI NOV 28 2014 MODELS SEEM TO BE OVERDOING THE AMOUNT OF LOW LEVEL SATURATION CURRENTLY ACROSS THE AREA...ESPECIALLY THE NAM. THERE IS AN MVFR DECK OF CLOUDS TO THE NORTH-WEST...ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE...FRONTOGENETIC FORCING...AND JUST NORTH OF A WARM FRONT. FARTHER SOUTH...SOME THIN MID CLOUDS WERE ALL THAT WAS EVIDENT. SOME SUGGESTION THAT THE LOW CIGS WILL SINK SOUTH ACROSS KRST/KLSE THIS EVENING...WITH PERHAPS SOME AID FROM POOLING MOISTURE ASSOCIATED WITH THE MELTING SNOW PACK. THIS COULD ALSO RESULT IN SOME BR...MOSTLY IN THE MVFR RANGE. HAVE PUSHED BACK THE ENCROACHMENT OF THE LOW CLOUDS BASED ON CURRENT TRENDS...AND WILL ADJUST AS/IF NEEDED. ASSUMING LOW CLOUDS DO MOVE IN...PROBABLY STICK AROUND THROUGH THE BETTER PART OF SATURDAY. SOMETHING ELSE TO WATCH - IF THE LOW CLOUDS ARE REALIZED LATER THIS AFTERNOON - THERE COULD BE A THREAT FOR SOME -FZDZ. CURRENT FORECAST BUFKIT SOUNDINGS ARE PROBABLY TOO SHALLOW IN SATURATION DEPTH...BUT IF ITS DEEPER...DRIZZLE PROCESS COULD GET GOING THANKS TO SOME WEAK LIFT THROUGH THE COLUMN. SOMETHING TO MONITOR. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...FREEZING RAIN ADVISORY UNTIL 9 PM CST THIS EVENING FOR WIZ029- 032>034-041>044. MN...FREEZING RAIN ADVISORY UNTIL 9 PM CST THIS EVENING FOR MNZ079- 086>088. IA...NONE. && $$ UPDATE...04 SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION.....RIECK
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
406 PM CST FRI NOV 28 2014 .TONIGHT...FORECAST CONFIDENCE MEDIUM. FREEZING RAIN AND SLEET DEVELOPED ACROSS SOUTHEAST MN EARLY THIS AFTERNOON WITHIN A REGION OF 850-700MB FRONTOGENESIS... A WEAK 500MB SHORTWAVE AND UPPER DIVERGENCE IN THE ENTRANCE REGION OF AN UPPER JET STREAK. THAT AREA IS TRACKING SOUTHEAST AND IS CURRENTLY OVER LA CROSSE AND SHOULD CONTINUE TO SPREAD SOUTHEAST INTO SOUTH CENTRAL WI. THE MIXED PRECIP TYPE IS DUE TO THE THERMAL PROFILE OF THE ATMOSPHERE. TEMPERATURES ARE WARMING ALOFT THIS AFTERNOON. THE MAX TEMP IS EXPECTED TO BE AROUND 800-850MB OF +4C AT MSN AT 00Z. THIS IS ALSO A DRY LAYER WITH THE WAA ADVECTING DRIER AIR IN FROM THE PLAINS. 500MB SHORTWAVE ENERGY AND UPPER DIVERGENCE IN THE ENTRANCE REGION OF A JET STREAK WILL LEAD TO ENHANCED UPWARD MOTION WITHIN THE DENDRITIC GROWTH ZONE... LOCATED AT 500-600MB LEVEL. IT IS TAKING TIME TO SATURATE FROM THE TOP DOWN TO PRODUCE LIGHT PRECIP AT THE GROUND. CEILINGS ARE QUITE HIGH UPSTREAM. THIS FORCING WILL ONLY BE OVER SOUTHERN WI FOR A SHORT TIME PERIOD THIS EVENING...SO THAT WILL LIMIT OUR AMOUNTS OF ANY ICE ACCUMULATION. DIURNAL CU DEVELOPED THIS AFTERNOON IN THE SUNNY AREAS AND THIS AREA IS TURNING INTO STRATUS AS IT GETS DARK AND IS ACTUALLY EXPANDING A LITTLE IN AREAL COVERAGE. THE LOWER CEILINGS WITHIN THIS BAROCLINIC ZONE/ DIURNAL CU ZONE ARE PAVING THE WAY FOR THIS FROZEN PRECIP LATE THIS AFTERNOON INTO THE EARLY EVENING. I HAVE HIGH CONFIDENCE THAT THE DELLS AREA WILL SEE A MIX OF FREEZING RAIN AND SLEET LATE THIS AFTERNOON AND INCREASING CONFIDENCE THAT MADISON WILL BE IMPACTED AS WELL. EVEN VERY LIGHT ACCUMULATIONS OF ICE WILL HAVE IMPACTS ON TRAVEL. WE WILL HANDLE THIS SITUATION WITH NOWCASTS AND SPECIAL WEATHER STATEMENTS AS IT EVOLVES. AFTER THE PRECIP ENDS WE WILL BEGIN WARMING AT THE SURFACE AS WARM AIR ADVECTION IN THE LOW LEVELS TAKES HOLD. TEMPERATURES ARE EXPECTED TO WARM INTO THE LOWER 30S BY EARLY MORNING AND INTO THE MID TO UPPER 40S NEAR THE WI/IL BORDER BY SATURDAY AFTERNOON. THIS BEGS THE QUESTION ABOUT HOW WIDESPREAD AND DENSE FOG WILL BECOME WITH WARM AIR ADVECTING OVER OUR SNOW PACK AND ALSO WITH SOME MELTING SNOW. DEWPOINT TEMPS ARE NOT EXPECTED TO RISE ABOVE FREEZING UNTIL SATURDAY AFTERNOON. THIS WILL KEEP OUR SNOW FROM RAPIDLY MELTING AND HELP TO KEEP THE DENSE FOG AWAY. SOME MODELS... ESPECIALLY THE NAM... ARE DEVELOPING DENSE FOG OVERNIGHT. THE NAM HAS BEEN OVERDOING THE LOW LEVEL MOISTURE LATELY DUE TO ITS ASSUMPTION OF DEEPER SNOW COVER THAN WHAT IS ACTUALLY THERE. IT IS ALSO ASSUMING THAT WE WILL BE MELTING A LOT OF SNOW OVERNIGHT. AFTER COORDINATION WITH THE SURROUNDING OFFICES... WE HAVE PATCHY TO AREAS OF FOG IN THE FORECAST BUT NOT EXPECTING WIDESPREAD DENSE FOG. .SHORT TERM...SATURDAY NIGHT THROUGH MONDAY NIGHT. SATURDAY NIGHT...FORECAST CONFIDENCE HIGH. A PAIR OF WEAK SHORT WAVES RIPPLE THROUGH IN FAST MOVING ZONAL FLOW SATURDAY NIGHT...RIDING 140 KT 250 MB JET STREAK. SOME WEAK VORTICITY ADVECTION/300-500MB Q-VECTOR CONVERGENCE IN THE EAST BETWEEN 00Z AND 06Z SUNDAY...WITH SECONDARY 850 MB THERMAL RIDGE NOSING INTO THE REGION AHEAD OF MID LEVEL TROUGH PRODUCING SOME ISENTROPIC ADIABATIC OMEGA. SOME WEAK SURFACE MOISTURE CONVERGENCE ALONG SURFACE TROUGH...BUT THIS LESSENS WITH TIME AS SURFACE LOW LIFTS AWAY TO THE NORTHEAST. HOWEVER DRY PLAINS AIR ADVECTING IN ON WSW WINDS KEEPING COLUMN DRY ABOVE 900 MB ON FORECAST SOUNDINGS...AND CONDENSATION PRESSURE DEFICITS AT OR ABOVE 100 MB INTO SUNDAY MORNING. COULD SEE SOME PATCHY DRIZZLE BUT MOIST LAYER TOO SHALLOW TO PRODUCE MEASURABLE PCPN. COULD ALSO SEE SOME PATCHY FOG...BUT LOW LEVEL SATURATION NOT EXTENSIVE ENOUGH...AND COLLABORATION LEADS TO NOT MENTIONING AT THIS TIME. TEMPS ONLY COOL ABOUT 5 TO 7 DEGREES FROM DAYTIME HIGHS EARLY IN THE EVENING THEN REMAIN STEADY UNTIL MIDNIGHT...COOLING AS COLD AIR ADVECTION BEGINS BEHIND TROUGH THAT EXITS THE SE CORNER OF STATE AROUND 12Z SUNDAY. SUNDAY THROUGH MONDAY NIGHT...FORECAST CONFIDENCE HIGH TEMPS REBOUND A FEW DEGREES WITH MIDDAY HIGHS SUNDAY...THEN FALL AS COLD AIR ADVECTION DROPS 925 MB TEMPS ON NW WINDS WITH SPRAWLING HIGH PRESSURE BUILDING IN...WHICH WILL DOMINATE THE WEATHER THROUGH THE REST OF THIS PERIOD. WILL SEE SINGLE DIGIT LOWS SUNDAY NIGHT...WITH APPARENT TEMPERATURES IN THE SINGLE DIGITS BELOW BY SUNRISE MONDAY. MONDAY HIGHS WELL BELOW NORMAL IN THE TEENS...WITH AROUND 20 ALONG THE LAKESHORE AND NEAR THE IL BORDER. WIND CHILL VALUES ONLY GET TO THE SINGLE DIGITS ABOVE ZERO. CORE OF THE HIGH MOVES ACROSS WISCONSIN MONDAY NIGHT...WITH CLEAR AND NEAR-CALM CONDITIONS DIPPING LOWS TO NEAR ZERO IN THE NW CWA...AND SINGLE DIGITS INLAND. LIGHT EASTERLY WINDS WILL KEEP LOCALES ALONG THE LAKE MICHIGAN SHORE BETWEEN 10F AND 15F ABOVE. .LONG TERM...TUESDAY THROUGH FRIDAY. FORECAST CONFIDENCE MEDIUM. SOME BETTER AGREEMENT AMONG THE LONGER RANGE MODELS...THOUGH DISCREPANCIES REMAIN. ECMWF AND GEM STILL DIGGING 500 MB TROUGH DEEPER THAN GFS TUESDAY NIGHT AND WEDNESDAY...BUT ALL KEEP SURFACE LOW AND ASSOCIATED PCPN WELL TO THE NORTH THROUGH WEDNESDAY MORNING...THEN HOLD OFF DEVELOPING PRECIP ALONG TRAILING SURFACE TROUGH UNTIL GULF MOISTURE WICKS UP BEHIND DEPARTING HIGH...WELL TO THE EAST OF THE STATE. GFS IS NOW CLOSER TO THE ECMWF IN KEEPING A WEAKER SRN STREAM WAVE MOVING THROUGH IN NEAR ZONAL FLOW THURSDAY NIGHT AND FRIDAY...THOUGH IT IS FASTER AND FOCUSING PCPN ALL SOUTH OF STATE. WILL KEEP LOW POPS IN FOR NOW AND AWAIT MORE CONSISTENT SIGNAL FROM MODELS. TEMPERATURES WORK BACK TOWARD SEASONAL NORMALS. && .AVIATION/00Z TAFS/... THERMAL PROFILES SUGGEST THAT ANY PRECIPITATION DURING THE LATE AFTERNOON AND EVENING WOULD BE FREEZING RAIN OR SLEET. THE LOW CEILINGS OVER MSN ARE GRADUALLY EXPANDING ACROSS SOUTHEAST WI LATE THIS AFTERNOON. THESE LOW CIGS WILL PAVE THE WAY FOR THIS LIGHT MIXY PRECIP THROUGH EARLY EVENING. SOUTHERLY WINDS AHEAD OF A COLD FRONT OVERNIGHT WILL PULL IN WARMER AND SOMEWHAT MORE MOIST AIR OVER SNOWPACK. PROBABILITIES OF IFR CEILINGS INCREASE...ESPECIALLY INTO MSN. NOT CONFIDENT THAT THE REALLY LOW IFR CIGS THAT THE NAM AND HRRR SUGGEST WILL PAN OUT. EXPECTING AREAS OF LIGHT FOG... PROBABLY NOT WIDESPREAD DENSE FOG. && .MARINE... SOUTHERLY WIND GUSTS AND WAVES ARE REACHING SMALL CRAFT ADVISORY LATE THIS AFTERNOON AND WILL LIKELY PERSIST THROUGH SATURDAY EVENING. THUS... ISSUED A SMALL CRAFT ADVISORY. BRISK NORTHWEST WINDS SUNDAY EVENING AND MONDAY WILL ALSO APPROACH SMALL CRAFT ADVISORY LEVELS IN THE WAKE OF A COLD FRONT. BRISK SOUTH WINDS ON TUESDAY AND TUESDAY NIGHT WILL ALSO GENERATE RATHER HIGH WAVES && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 10 PM CST SATURDAY FOR LMZ643>646. && $$ TONIGHT/SATURDAY AND AVIATION/MARINE...MRC SATURDAY NIGHT THROUGH FRIDAY...REM
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
355 PM CST FRI NOV 28 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 AT 3 PM...A BAND OF MODERATE TO STRONG 700 TO 500 MB FRONTOGENESIS WAS STARTING TO MOVE EAST INTO WEST CENTRAL WISCONSIN. THIS BAND HAS PRODUCED AREAS OF FREEZING RAIN AND OCCASIONALLY SOME ICE PELLETS ACROSS SOUTHEAST MINNESOTA. PERIODIC CHECKS WITH LAW ENFORCEMENT AND SPOTTERS HAVE NOT INDICATED TOO MUCH OF AN IMPACT FROM IT. IT JUST STARTED HERE AT THE OFFICE AND IT IS FREEZING ON THE VEHICLES AND SLICK SPOTS ON UNTREATED SIDEWALKS. HAVE TO ISSUE A SPECIAL WEATHER STATEMENT FOR AREAS ALONG AND NORTH OF INTERSTATE 90 TO COVER THE POTENTIAL FOR LIGHT ICING ON UNTREATED SURFACES. FOR THIS EVENING...THE 28.18Z RAP AND NAM SHOW THAT THIS BAND WILL CONTINUE TO MOVE EAST ACROSS WEST CENTRAL...CENTRAL...AND NORTH CENTRAL WISCONSIN. AS IT MOVES INTO NORTH CENTRAL WISCONSIN... SOUNDINGS SUGGEST THAT THERE MAY BE A BRIEF PERIOD OF SNOW MIXING IN WITH THIS WINTRY MIX. SOME OF THE MESO MODELS SUGGEST UP TO A TENTH OF AN INCH OF QPF. THIS SEEMS TO BE A BIT ON THE HIGH SIDE CONSIDERING THE DRY AIR BETWEEN 700 TO 850 MB...SO HAVE LIQUID AMOUNTS OF 0.01 TO 0.03 INCHES. FOR OVERNIGHT...EXPECT THE WINTRY PRECIPITATION TO BE IN CLARK AND TAYLOR COUNTIES...AND THEN MOVE OUT BY 3 AM. THERE MAY BE SOME VERY LIGHT ICING. STRONG WARM AIR ADVECTION WILL CAUSE RISING TEMPERATURES THROUGH THE NIGHT. TEMPERATURES WILL RISE FROM THE LOWER TO MID 20S INTO THE MID AND UPPER 20S BY MORNING. AS THIS WARM AIR MOVES OVER THE SNOW PACK...THERE MAY BE SOME AREAS OF FOG. ON SATURDAY...THE TEMPERATURE FORECAST IS PROBLEMATIC DUE TO THE SNOW COVER. THE NAM SNOW COVER IS INITIALIZED TOO HIGH. IT HAS SNOW DEPTHS OF 4 TO 8 INCHES. WE ARE ACTUALLY MORE IN THE TRACE TO 4 INCHES...SO SOME OF THE WARMING IN THE MODELS IS GOING TO SNOW MELT INSTEAD OF WARMING THE AIR MASS NEAR THE GROUND. THE WARMEST 925 AND 850 MB TEMPERATURES ARE LOCATED ALONG AND SOUTH OF INTERSTATE 90. 925 MB TEMPERATURES WILL CLIMB TO 0 TO 8C INTO THESE AREAS...SO A BIT CONCERNED THAT THE TEMPERATURES COULD WARM A BIT WARMER THAN THE LOW TO MID 40S THAT ARE CURRENTLY FORECAST. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 350 PM CST FRI NOV 28 2014 ON SATURDAY NIGHT AND SUNDAY MORNING...THE FIRST OF 2 ARCTIC COLD FRONT WILL MOVE SOUTHEAST THROUGH THE AREA. 850 MB TEMPERATURES FALL FROM 6 TO 10C INTO -7 TO -15C. THE STRONG COLD AIR ADVECTION WILL CAUSE TEMPERATURES TO SLOWLY FALL THROUGH MUCH OF THE DAY. WAS INITIALLY CONCERNED ABOUT STRONG WINDS ADVECTING TO THE SURFACE DUE TO STRONG SUBSIDENCE IN THE WAKE OF THIS FRONT. HOWEVER SOUNDINGS CONTINUE TO SHOW THAT THE WINDS WILL STAY MAINLY IN THE 15 TO 25 MPH. THIS WILL PRODUCE WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. ON SUNDAY NIGHT...ANOTHER COLD FRONT WILL MOVE THROUGH THE AREA. THIS WILL LOWER 850 MB TEMPERATURES DOWN INTO THE -15C TO -19C FOR MONDAY MORNING BEFORE WARM AIR ADVECTION STARTS TO DEVELOP ACROSS THE AREA DURING THE AFTERNOON AND MONDAY NIGHT. HIGH TEMPERATURES ON MONDAY WILL RANGE FROM 5 TO 15 DEGREES. LIGHTER WINDS WILL KEEP WIND CHILLS IN THE 10 BELOW TO 10 ABOVE RANGE. FROM THURSDAY INTO THURSDAY NIGHT...THE MODELS CONTINUE TO STRUGGLE WITH WHETHER A LOW PRESSURE SYSTEM WILL BRING PRECIPITATION TO THE AREA. THE GFS AND ECMWF ARE NOW SIMILAR WITH THE TRACK THROUGH THE MID MISSISSIPPI RIVER VALLEY AND WESTERN GREAT LAKES. HOWEVER THEY ARE 12 HOUR APART. PRECIPITATION TYPE WILL BE SNOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1110 AM CST FRI NOV 28 2014 MODELS SEEM TO BE OVERDOING THE AMOUNT OF LOW LEVEL SATURATION CURRENTLY ACROSS THE AREA...ESPECIALLY THE NAM. THERE IS AN MVFR DECK OF CLOUDS TO THE NORTH-WEST...ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE...FRONTOGENETIC FORCING...AND JUST NORTH OF A WARM FRONT. FARTHER SOUTH...SOME THIN MID CLOUDS WERE ALL THAT WAS EVIDENT. SOME SUGGESTION THAT THE LOW CIGS WILL SINK SOUTH ACROSS KRST/KLSE THIS EVENING...WITH PERHAPS SOME AID FROM POOLING MOISTURE ASSOCIATED WITH THE MELTING SNOW PACK. THIS COULD ALSO RESULT IN SOME BR...MOSTLY IN THE MVFR RANGE. HAVE PUSHED BACK THE ENCROACHMENT OF THE LOW CLOUDS BASED ON CURRENT TRENDS...AND WILL ADJUST AS/IF NEEDED. ASSUMING LOW CLOUDS DO MOVE IN...PROBABLY STICK AROUND THROUGH THE BETTER PART OF SATURDAY. SOMETHING ELSE TO WATCH - IF THE LOW CLOUDS ARE REALIZED LATER THIS AFTERNOON - THERE COULD BE A THREAT FOR SOME -FZDZ. CURRENT FORECAST BUFKIT SOUNDINGS ARE PROBABLY TOO SHALLOW IN SATURATION DEPTH...BUT IF ITS DEEPER...DRIZZLE PROCESS COULD GET GOING THANKS TO SOME WEAK LIFT THROUGH THE COLUMN. SOMETHING TO MONITOR. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...BOYNE LONG TERM...BOYNE AVIATION.....RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS MILWAUKEE/SULLIVAN WI
1222 PM CST FRI NOV 28 2014 .UPDATE... THE MORNING SNOW MOVED OUT OF SOUTHERN WI AND THERE IS SUNSHINE WEST OF MADISON. THERE IS A LOT OF UNCERTAINTY ABOUT WHAT IS GOING TO HAPPEN WITH THE CLOUDS AND PRECIP CHANCES FOR THE LATE AFTERNOON/EARLY EVENING TIME PERIOD. THE 12Z MODELS ARE STILL SHOWING LIGHT QPF OVER ALMOST ALL OF SOUTHERN WI. THIS IS DUE TO 850- 700MB FRONTOGENESIS MOVING THROUGH. THE UNCERTAINTY IS HOW MUCH DRY AIR WILL HINDER PRECIP DEVELOPMENT AND ALSO WHAT TYPE OF PRECIP WOULD HIT THE GROUND. TEMPERATURES WILL BE WARMING ALOFT THROUGH THE AFTERNOON WITH MAX TEMP AROUND 800-850MB OF +4C AT MSN. THIS IS ALSO A DRY LAYER WITH THE WAA ADVECTING DRIER AIR IN FROM THE PLAINS. 500MB SHORTWAVE ENERGY AND UPPER DIVERGENCE IN THE ENTRANCE REGION OF A JET STREAK WILL LEAD TO ENHANCED UPWARD MOTION WITHIN THE DENDRITIC GROWTH ZONE... LOCATED AT 500-600MB LEVEL. THIS LAYER WILL ALSO BE SATURATED. IT IS HARD TO IGNORE THIS SIGNAL EVEN THOUGH THERE MAY BE A DRY LAYER IN THE LOWER LEVELS. IF THERE IS ENOUGH FORCING ALOFT... THEN THERE IS A GOOD CHANCE IT WILL BE ABLE TO SATURATE FROM THE TOP DOWN AND PRODUCE LIGHT PRECIP AT THE GROUND... GIVEN ENOUGH TIME. THE ONLY THING IS THAT IT WILL BE A SHORT-LIVED EVENT OVER SOUTHERN WI. THE TEMPERATURE PROFILE WILL DETERMINE WHAT PRECIP TYPE IT WILL BE... BUT LIKELY A MIX OF SLEET AND FREEZING RAIN THAT CHANGES TO SNOW BEFORE ENDING... ALL WITHIN A 2 TO 3 HOUR PERIOD. THE GFS BRINGS IT FURTHER SOUTH ACROSS SOUTHERN WI THAN THE NAM... AND ALSO A LITTLE EARLIER THAN THE NAM. WE WILL BE WATCHING TRENDS UPSTREAM OVER SOUTHERN MN AND NORTHERN IOWA EARLY THIS AFTERNOON. && .AVIATION/18Z TAFS/... THERMAL PROFILES SUGGEST THAT ANY PRECIPITATION DURING THE LATE AFTERNOON AND EVENING WOULD BE FREEZING RAIN OR SLEET. THERE IS STILL A LOT OF UNCERTAINTY ABOUT WHETHER OR NOT IT WILL DEVELOP. IF IT DOES... EXPECT ONLY LIGHT AMOUNTS WITH SLEET OR FREEZING RAIN POSSIBLY CHANGING OVER TO SNOW BEFORE ENDING... ALL WITHIN A 2-3 HOUR PERIOD. RIGHT AHEAD OF A COLD FRONT OVERNIGHT...SOUTH WINDS PULL IN WARMER AND SOMEWHAT MORE MOIST AIR OVER SNOWPACK AND PROBABILITIES OF IFR CEILINGS INCREASE...ESPECIALLY INTO MSN. NOT CONFIDENT THAT THE REALLY LOW IFR CIGS THAT THE NAM AND HRRR SUGGEST WILL PAN OUT. && .PREV DISCUSSION... /ISSUED 548 AM CST FRI NOV 28 2014/ UPDATE... BASED ON RADAR TRENDS OVER THE DAKOTAS...00Z ECMWF...06Z GFS/NAM...AND LATEST HRRR/RAP...HAVE DECIDED TO BOOST AFTERNOON POPS WITH SECOND WAVE OF PRECIPITATION WHICH WILL BE FREEZING RAIN AND SLEET AS WARM LAYER MOVES IN. FAR NORTHEAST MAY HOLD ONTO ALL SNOW SO THAT 1-2 INCH AMOUNTS HOLD TRUE. PREV DISCUSSION... /ISSUED 340 AM CST FRI NOV 28 2014/ TODAY...FORECAST CONFIDENCE IS MEDIUM. WESTERLY FLOW HAS ALLOWED MILD PACIFIC AIR TO SPREAD ACROSS NORTHERN ROCKIES INTO CENTRAL PLAINS. STRONG WARM ADVECTION PUSHING ACROSS WISCONSIN THIS MORNING WITH A FEW HOURS OF SNOW. NOT MUCH ALONG THE IL BORDER...BUT 1-2" OF SNOW IN THE SHEBOYGAN AREA. MOST AREAS JUST RECEIVE A DUSTING. SOME OF THE MODELS HAVE A SECOND BATCH OF PRECIPITATION THIS AFTERNOON. THIS IS DURING A PERIOD WHERE A WARM LAYER DEVELOPS AND WOULD SUGGESTION FREEZING RAIN POTENTIAL...ESPECIALLY IN THE SOUTHWEST. MOST OF THE LIFT AND MOISTURE BY THIS TIME IS PRETTY HIGH UP...WITH RATHER DRY AIR IN LOW LEVELS NEAR THE WARM NOSE. WILL LEAN ON THE DRIER SIDE BUT CERTAINLY WILL NEED TO BE WATCHED. TONIGHT...FORECAST CONFIDENCE IS MEDIUM. THINGS DRY OUT ALOFT BUT GUIDANCE SHOWS INCREASING MOISTURE IN THE BOUNDARY LAYER WITH SOUTHERLY WINDS AHEAD OF FRONT. LOOKS LIKE A STRATUS DECK WILL FORM BUT MOST OF THE UNCERTAINTY IS IN WHETHER IT WILL BECOME AN ADVECTION SNOW EVENT OVER THE SNOWPACK. HIGH CONFIDENCE IN VERY LOW CLOUDS BUT LOW CONFIDENCE IN DENSE FOG. TEMPERATURES LIKELY TO RISE DURING THE NIGHT. SHORT TERM...SATURDAY THROUGH SUNDAY NIGHT...FORECAST CONFIDENCE IS MEDIUM. SYNOPTIC MODELS IN GOOD AGREEMENT WITH WARM AIR ADVECTION CONTINUING ACROSS THE AREA SATURDAY AND SATURDAY NIGHT...WITH GENERALLY ZONAL 500 MB FLOW. THERE ARE SIGNIFICANT DIFFERENCES WITH LOW LEVEL MOISTURE PROFILES BETWEEN THE NAM/GFS AND ECMWF/CANADIAN MODELS. THE NAM/GFS HOLD ONTO SATURATED BOUNDARY LAYER BELOW INVERSION DURING THIS TIME...WHILE THE ECMWF/CANADIAN MODELS ARE DRIER. THIS RESULTS IN THE NAM/GFS SHOWING BLOTCHY QPF ACROSS THE AREA SATURDAY INTO SATURDAY NIGHT...INDICATIVE OF DRIZZLE/VERY LIGHT RAIN. MOS GUIDANCE ALSO SHOWING SOME FOG DEVELOPMENT IN THE AREA AS WELL SATURDAY MORNING. THE ECMWF/CANADIAN MODELS ARE DRY DURING THIS TIME. NAM/GFS HAVE BEEN OVERDONE WITH BOUNDARY LAYER MOISTURE IN THE RECENT AND DISTANT PAST...ESPECIALLY THE NAM...SO AM SKEPTICAL ON THE DRIZZLE/VERY LIGHT RAIN AND FOG. FOR NOW...CONTINUED TO KEEP SATURDAY AND SATURDAY NIGHT DRY...WITH SKIES BECOMING PARTLY CLOUDY SATURDAY NIGHT. MILD TEMPERATURES IN THE LOWER TO MID 40S ARE EXPECTED SATURDAY...HOLDING IN THE 30S SATURDAY NIGHT. MODELS BRING SURFACE COLD FRONT SOUTHEAST INTO THE AREA LATER SATURDAY NIGHT AND THROUGH THE AREA BY MIDDAY SUNDAY. KEPT FORECAST DRY FOR NOW WITH LACK OF DEEP MOISTURE AVAILABLE. STRONG COLD AIR ADVECTION THEN TAKES OVER FOR LATER SUNDAY INTO SUNDAY NIGHT...AS STRONG HIGH PRESSURE MOVES INTO THE NORTHERN PLAINS. THIS WILL BRING COLD TEMPERATURES BACK INTO THE AREA. TEMPERATURES SHOULD FALL THROUGH THE 30S ON SUNDAY...AND INTO THE TEENS SUNDAY NIGHT. LONG TERM...MONDAY THROUGH THURSDAY...FORECAST CONFIDENCE IS MEDIUM. GFS/ECMWF IN FAIR AGREEMENT WITH STRONG HIGH PRESSURE MOVING SOUTHEAST INTO THE AREA MONDAY...MAINTAINING THE COLD TEMPERATURES OVER THE AREA. 500 MB FLOW REMAINS FAIRLY ZONAL OVER THE REGION. THE HIGH WILL SHIFT EAST OF THE REGION MONDAY NIGHT...ALLOWING FOR WARM AIR ADVECTION TO KICK IN AND REMAIN INTO TUESDAY. THIS SHOULD BRING A BRIEF REBOUND IN TEMPERATURES. A COLD FRONT THEN SLIDES SOUTHEAST THROUGH THE AREA TUESDAY NIGHT...WITH LOW POPS REMAINING IN THE FAR EAST. MAY BE ABLE TO REMOVE THESE LOW POPS IN LATER FORECASTS IF MODELS CONTINUE THE DRY TREND TUESDAY NIGHT. ANOTHER HIGH PASSING SOUTHEAST THROUGH THE REGION WEDNESDAY INTO WEDNESDAY NIGHT SHOULD BRING ANOTHER BRIEF SHOT OF COLD AIR. GFS THEN BRINGS A BROAD AREA OF QPF WITHIN A WARM AIR ADVECTION REGIME INTO THE REGION THURSDAY...WITH THE ECMWF KEEPING ANY QPF WELL SOUTHWEST OF THE AREA. FOR NOW...WILL USE CONSENSUS POPS AND TEMPERATURES THIS FAR OUT. AVIATION/12Z TAFS/... BATCH OF SNOW THIS MORNING WILL MAINLY IMPACT AREAS NORTH OF THE TAF SITES. HOWEVER...BRIEF MVFR CONDITIONS AND A DUSTING OF SNOW EXPECTED. THERMAL PROFILES SUGGEST THAT ANY PRECIPITATION DURING THE LATE AFTERNOON AND EVENING WOULD BE FREEZING RAIN OR SLEET. HOWEVER...DO NOT EXPECT MUCH PRECIPITATION SO THIS SHOULD NOT BE AN IMPACT. RIGHT AHEAD OF COLD FRONT OVERNIGHT...SOUTH WINDS PULL IN WARMER AND SOMEWHAT MORE MOIST AIR OVER SNOWPACK AND PROBABILITIES OF IFR CEILINGS INCREASE...ESPECIALLY INTO MSN. MARINE... SOUTHERLY WINDS AND WAVES WILL APPROACH SMALL CRAFT ADVISORY THIS AFTERNOON AND EVENING BUT MARGINAL NATURE OF EVENT DOES NOT APPEAR TO WARRANT A SMALL CRAFT ADVISORY. BRISK NORTHWEST WINDS SUNDAY EVENING AND MONDAY WILL ALSO APPROACH SMALL CRAFT ADVISORY LEVELS IN THE WAKE OF A COLD FRONT. BRISK SOUTH WINDS ON TUESDAY AND TUESDAY NIGHT WILL ALSO GENERATE RATHER HIGH WAVES. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...NONE. LM...NONE. && $$ UPDATE...MRC TODAY/TONIGHT AND AVIATION/MARINE...CRAVEN SATURDAY THROUGH THURSDAY...WOOD
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1110 AM CST FRI NOV 28 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 221 AM CST FRI NOV 28 2014 CURRENTLY AS OF 08Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED DEEP...POTENT TROUGHS OVER BRITISH COLUMBIA AND OFF THE COAST OF CALIFORNIA...RIDGING OVER THE WESTERN U.S. AND TROUGHING OVER THE EASTERN U.S.. A SHORTWAVE WAS EVIDENT RIDING THROUGH THE NORTHWEST FLOW FROM NORTHWEST MN INTO WESTERN WI. DPVA FROM THIS SHORTWAVE COMBINED WITH WARM ADVECTION AND PRECIPITABLE WATER NEAR 0.5 INCHES HAS HELPED SUPPORT AN AREA OF SNOW FROM CENTRAL MN INTO THE FORECAST AREA. THE AFOREMENTIONED WARM ADVECTION WAS NICELY EVIDENT AT 850MB FROM 00Z RAOBS WITH READINGS IN THE 8-12C RANGE IN WESTERN SOUTH DAKOTA AND NEBRASKA...COMPARED TO -10 TO -14C OVER THE FORECAST AREA. THIS TIGHT TEMPERATURE GRADIENT WAS ADVECTING EASTWARD BY A 30- 40 KT SOUTHWEST WIND PER VWP/PROFILER DATA. INTERESTINGLY TOO... SURFACE DEWPOINTS OVER WESTERN SOUTH DAKOTA AND NEBRASKA WERE IN THE 20S...ABOUT 10F WARMER THAN CURRENT TEMPERATURES OVER THE FORECAST AREA. GOOD MODEL AGREEMENT EXISTS ON THE 500MB FLOW PATTERN THROUGH THE SHORT TERM PERIOD...SHOWING THE WESTERN U.S. RIDGE FLATTENING OUT AND GETTING PUSHED EASTWARD BY THE POTENT BRITISH COLUMBIA TROUGH DROPPING INTO THE PACIFIC NORTHWEST. THIS PATTERN EVOLUTION RESULTS IN CONTINUOUS WARM AND MOIST AIR ADVECTION FROM SOUTH DAKOTA AND NEBRASKA TOWARDS THE FORECAST AREA. REGARDING THE CURRENT SNOW...REPRESENTED WELL BY 800-700MB FRONTOGENESIS...ANTICIPATING THE EASTWARD PUSH WITH THE UPPER FLOW WILL HELP KEEP THE SNOWBAND MOVING EASTWARD THROUGH THE DAY. THERE COULD BE A SECOND...CALL IT SURGE...OF SNOW AND FRONTOGENESIS DROPPING THROUGH NORTHERN WI LATE THIS MORNING INTO THIS AFTERNOON AS SUGGESTED BY HIGH RESOLUTION MODEL GUIDANCE. THEREFORE...HAVE KEPT THE WINTER WEATHER ADVISORY IN TACT FOR TAYLOR COUNTY. ALSO LATE THIS MORNING THROUGH THE AFTERNOON...WE MAY HAVE TO CONTEND WITH ANOTHER BAND OF PRECIPITATION. THIS BAND CAN CURRENTLY BE SEEN COMING INTO THE WESTERN DAKOTAS ASSOCIATED WITH A SHORTWAVE JUST WEST OF IT...WHICH THE 28.00Z GFS/NAM/HIRES-ARW/NMM AND LATEST RAP/HRRR WANT TO TRAVERSE IT ACROSS LOCATIONS SOUTHWEST OF I-94. THERE COULD BE MID-LEVEL SATURATION ISSUES IN THE WAKE OF THE CURRENT SNOW...BUT MODELS DO WANT TO SATURATE THINGS BACK UP. THEREFORE...HAVE ADDED SOME PRECIPITATION CHANCES. TRACK WISE... REFER THE MORE NORTHERN RAP/HRRR OVER THE FARTHER SOUTH NAM/HIRES- ARW/NMM AS THE FARTHER SOUTH MODELS ARE WAY TOO INTENSE AND TOO FAR SOUTH COMPARED TO CURRENT RADAR IMAGERY. PRECIPITATION TYPE BECOMES AN ISSUE WITH THIS WAVE AS WELL WITH WARMER AIR COMING IN ALOFT. COMPARING MODEL DERIVED REFLECTIVITY OUTPUT WITH THE MAXIMUM TEMPERATURE ALOFT...THE SOUTHWESTERN EDGE MAY POSE A MIX WITH SLEET OR EVEN FREEZING RAIN CONCERN. SINCE THERE IS VERY LOW CONFIDENCE ON ANY SLEET/FREEZING RAIN OCCURRING...HAVE NOT ISSUED ANY WINTER WEATHER ADVISORY FOR THIS WAVE OF PRECIPITATION. AS WE HEAD INTO TONIGHT...CONCERN SHIFTS TO THE CONTINUOUS ADVECTION OF LOW LEVEL MOISTURE. SURFACE DEWPOINTS LATE THIS AFTERNOON COULD BE AS HIGH AS THE MID TO UPPER 30S ALONG I-29 ON THE WESTERN EDGE OF THE SNOWPACK. AS THIS HIGHER MOISTURE TRIES TO ADVECT ACROSS THE SNOWPACK INTO THE FORECAST AREA...WHICH MAY ALREADY HAVE DECENT LOW LEVEL SATURATION FROM THE WAVES OF PRECIPITATION MOVING THROUGH TODAY...ANTICIPATING VERY LOW STRATUS AND FOG TO DEVELOP. WARMER AIR MOVING IN ALOFT NOTED BY 850MB TEMPS CLIMBING TO 6-10C SHOULD ONLY FURTHER STRENGTHEN AN INVERSION...AIDING IN TRAPPING THE LOW LEVEL MOISTURE. HIGHER TERRAIN LOCATIONS SHOULD BE MOST SUSCEPTIBLE TO FOG. LATER SHIFTS MAY NEED TO CONSIDER A DENSE FOG ADVISORY... PARTICULARLY ALONG AND SOUTH OF I-90. WITH THE STRATUS IN PLACE AND IN A GENERAL WARM ADVECTION REGIME...ANTICIPATING VERY LITTLE FALL IN TEMPERATURES TONIGHT FROM AFTERNOON HIGHS. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 221 AM CST FRI NOV 28 2014 FOCUS OF ATTENTION FOR THE FIRST PART OF THE LONG TERM PERIOD IS SQUARELY ON THE POTENT TROUGH OVER THE PACIFIC NORTHWEST AT 12Z SATURDAY. MODELS ARE IN GOOD AGREEMENT MARCHING THIS FEATURE EASTWARD THROUGH THE WEEKEND WITH ITS AXIS OVER THE FORECAST AREA BY 12Z MONDAY. PRIOR TO ITS ARRIVAL...925MB TEMPS ARE PROGGED TO CONTINUING WARMING THROUGH THE DAY SATURDAY...CLIMBING TO PERHAPS AS MUCH AS 4-9C. DESPITE STRATUS AND MORNING FOG...THESE READINGS SHOULD ALLOW FOR HIGHS IN THE UPPER 30S TO MID 40S...WITH EVEN A SMALL CHANCE OF HITTING 50 IN VALLEY AREAS AS SUGGESTED BY THE REGIONAL CANADIAN. A SERIES OF TWO COLD FRONTS ARE THEN PROGGED TO MOVE THROUGH THE AREA DURING THE OVERNIGHT HOURS OF SATURDAY NIGHT INTO SUNDAY AS THE TROUGH APPROACHES...RESULTING IN A FALLING TEMPERATURE TREND. 925MB TEMPS PLUMMET TO -14C SOUTH TO -20C NORTH BY 12Z MONDAY. A 25-35KT NORTHWEST WIND AT 925MB SUNDAY INTO SUNDAY NIGHT ALSO ADDS IN A WIND CHILL FACTOR. LOWS SUNDAY NIGHT LOOK TO DROP INTO THE SINGLE DIGITS ABOVE ZERO...A NEAR 40 DEGREE TEMPERATURE DROP FROM SATURDAYS HIGHS. MAY HAVE TO WATCH FOR A POSSIBLE WIND CHILL ADVISORY MONDAY MORNING. PRECIPITATION CHANCES LOOK VERY LOW THROUGH THE WEEKEND DESPITE THE APPROACH OF THE POTENT TROUGH...MOSTLY DUE TO A LACK OF MOISTURE. MONDAY AND MONDAY NIGHT FEATURE CHILLY CONDITIONS AS AN ARCTIC HIGH PRESSURE AREA BUILDS INTO THE REGION FROM THE DAKOTAS. DESPITE ANOTHER SUNNY DAY LIKE YESTERDAY...HIGHS ON MONDAY SHOULD STRUGGLE TO CLIMB INTO THE TEENS. SOME PLACES IN SOUTHEAST MN AND NORTH CENTRAL WI MAY NOT EVEN GET TO 10 ABOVE. THIS SETS THE STAGE FOR TEMPERATURES TO TANK MONDAY EVENING WITH LIGHT WINDS. HOWEVER...THE HIGH DOES MOVE OFF TO THE EAST QUICKLY AFTER MIDNIGHT MONDAY NIGHT...RESULTING IN WARM ADVECTION ACROSS THE FORECAST AREA AND RISING TEMPERATURES. SO...THE BIG QUESTION IS HOW LOW CAN TEMPERATURES DROP PRIOR. THE EC AND CANADIAN SHOW POTENTIAL FOR 10S BELOW ZERO IN SOUTHEAST MN AND NORTH CENTRAL WI...WHEREAS MEX GUIDANCE IS MORE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO. SPLIT THE DIFFERENCE FOR NOW FOR LOWS. FOR THE REST OF NEXT WEEK...ANOTHER TROUGH IS PROGGED TO DROP DOWN INTO THE REGION FOR TUESDAY INTO WEDNESDAY. MUCH OF THE COLD AIR WITH THIS TROUGH...AS WELL AS POTENTIAL FOR PRECIPITATION...STAYS TO THE NORTH OF THE FORECAST AREA. IN FACT...THERE SHOULD BE A GOOD REBOUND IN TEMPERATURES FOR TUESDAY AS 925MB TEMPS CLIMB TO -4 TO - 6C. WARM ADVECTION RETURNS FOR WEDNESDAY NIGHT INTO THURSDAY AS THE UPPER FLOW TURNS ZONAL AGAIN...ALLOWING FOR ANOTHER REBOUND FOR TEMPERATURES. HOWEVER...THERE ARE SUGGESTIONS IN THE 28.00Z GFS AND 27.18Z DGEX FOR SOME LIGHT PRECIPITATION TO SPREAD INTO THE REGION AS MOISTURE ALSO RETURNS. THE 28.00Z ECMWF/CANADIAN CONTINUE TO POINT DRY...BUT FOR NOW IN COLLABORATION WITH NEIGHBORING OFFICES HAVE INTRODUCED 20 PERCENT CHANCES FOR THURSDAY FROM A MODEL CONSENSUS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1110 AM CST FRI NOV 28 2014 MODELS SEEM TO BE OVERDOING THE AMOUNT OF LOW LEVEL SATURATION CURRENTLY ACROSS THE AREA...ESPECIALLY THE NAM. THERE IS AN MVFR DECK OF CLOUDS TO THE NORTH-WEST...ASSOCIATED WITH AN UPPER LEVEL SHORTWAVE...FRONTOGENETIC FORCING...AND JUST NORTH OF A WARM FRONT. FARTHER SOUTH...SOME THIN MID CLOUDS WERE ALL THAT WAS EVIDENT. SOME SUGGESTION THAT THE LOW CIGS WILL SINK SOUTH ACROSS KRST/KLSE THIS EVENING...WITH PERHAPS SOME AID FROM POOLING MOISTURE ASSOCIATED WITH THE MELTING SNOW PACK. THIS COULD ALSO RESULT IN SOME BR...MOSTLY IN THE MVFR RANGE. HAVE PUSHED BACK THE ENCROACHMENT OF THE LOW CLOUDS BASED ON CURRENT TRENDS...AND WILL ADJUST AS/IF NEEDED. ASSUMING LOW CLOUDS DO MOVE IN...PROBABLY STICK AROUND THROUGH THE BETTER PART OF SATURDAY. SOMETHING ELSE TO WATCH - IF THE LOW CLOUDS ARE REALIZED LATER THIS AFTERNOON - THERE COULD BE A THREAT FOR SOME -FZDZ. CURRENT FORECAST BUFKIT SOUNDINGS ARE PROBABLY TOO SHALLOW IN SATURATION DEPTH...BUT IF ITS DEEPER...DRIZZLE PROCESS COULD GET GOING THANKS TO SOME WEAK LIFT THROUGH THE COLUMN. SOMETHING TO MONITOR. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM....AJ AVIATION.....RIECK