Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 02/02/15


AREA FORECAST DISCUSSION
NWS PHOENIX AZ
735 PM MST SUN FEB 1 2015 .SYNOPSIS... THE COMBINATION OF LINGERING MOISTURE...CLEAR SKIES...AND LIGHT WINDS WILL ALLOW PATCHY FOG TO DEVELOP AGAIN TONIGHT ACROSS PARTS OF SOUTH CENTRAL ARIZONA. HIGH PRESSURE WILL BUILD INLAND ACROSS THE DESERT SOUTHWEST BRINGING DRY WEATHER AND A WARMING TREND...ALONG WITH MOSTLY CLEAR SKIES THROUGH THE UPCOMING WEEK. HIGHS WILL APPROACH 80 DEGREES IN LOWER DESERTS COMMUNITIES BY THE END OF THE WEEK. && .DISCUSSION... DRYING ANTI-CYCLONIC FLOW HAS BECOME FULLY ESTABLISHED OVER THE SWRN CONUS EARLY THIS EVENING WITH RISING HEIGHTS AND THERMAL PROFILES ALOFT. HOWEVER...RECENT RAINFALL HAS MAINTAINED NEAR SFC MOISTURE WITH CNTRL ARIZONA DEWPOINTS HOVERING IN THE UPPER 40S/LOW 50S. STILL WATCHING FOR POTENTIAL FOG FORMATION TONIGHT...HOWEVER NUMEROUS FACTORS ARGUE FOR FAR LESS COVERAGE AND DENSITY AS COMPARED TO LAST NIGHT AND THIS MORNING. GIVEN AFTERNOON DEWPOINTS TEMPORARILY DROPPING INTO THE MIDDLE/UPPER 40S...AND 00Z KTWC SOUNDING DATA SHOWING MIXED LOW LEVEL PROFILES ONLY NEAR 6 G/KG...NEAR SFC MOISTURE WILL NOT BE QUITE AS PLENTIFUL AS SATURDAY NIGHT. BY THE TRADITIONAL CROSSOVER METHOD...ONLY LIGHT FOG WOULD BE FORECAST IN PRIMARILY NORTHERN PINAL COUNTY. IN ADDITION...MORE EXTENSIVE CIRRUS WAS QUICKLY SPILLING INTO THE REGION WHICH WILL PARTIALLY HAMPER OPTIMAL NOCTURNAL COOLING. 18Z NAM AND GFS FORECAST BUFR SOUNDINGS DEPICT A FAR DIFFERENT APPEARANCE NEAR THE SFC VERSUS LAST NIGHT...MORE INDICATIVE OF PATCHY LIGHT FOG AND DEW DEPOSITION. MODEL OUTPUT ALSO ARGUES AGAINST EXTENSIVE FOG COVERAGE WITH SUBJECTIVE ADVANCING HRRR FORECAST TRENDS SHOWING THICKER FOG LIMITED TO SMALLER AREAS OF PINAL COUNTY AND ONLY HAZE IN MARICOPA COUNTY. TIME LAGGED RAPID REFRESH DATA ALSO OBJECTIVELY PINPOINTS AREAS SOUTH OF PHOENIX WITH 60-70% CHANCES OF MORE DENSE FOG...WITH LITTLE CHANCE TO THE NORTH. WILL ONLY MAKE SOME MINOR ADJUSTMENTS TO AREAL EXTENT OF PATCHY FOG COVERAGE BASED MAINLY ON HRRR TRENDS. && .PREVIOUS DISCUSSION... /155 PM MST SUN FEB 1 2015/ AS FAR AS THE FORECAST FOR TONIGHT IS CONCERNED...ONCE AGAIN THE POSSIBILITY OF FOG WILL BE THE MAIN ISSUE. THE COMBINATION OF A STILL-MOIST BOUNDARY LAYER/SOIL MOISTURES...LIGHT WINDS...AND CLEAR SKIES IS EXPECTED TO ALLOW TEMPERATURES TODAY TO FALL VERY CLOSE TO THE DEWPOINT VALUES ACROSS SOUTH-CENTRAL ARIZONA...WHICH WOULD ALLOW FOG TO ONCE AGAIN FORM TOWARDS MORNING. HOWEVER...STRONG SUBSIDENCE ALOFT IS EXPECTED TO BEGIN TO PUSH DRIER AIR DOWNWARD AND COMPRESS THE BOUNDARY LAYER BY LATE TONIGHT...WHICH SHOULD HELP TO INHIBIT FOG FORMATION SOMEWHAT. AT THIS POINT...CURRENT THINKING IS THAT PATCHY FOG WILL FORM...BUT SHOULD...FOR THE MOST PART...NOT BECOME ANYWHERE AS DENSE AS WE SAW THIS MORNING...AND CLEAR EARLIER...IN THE 16-17Z TIMEFRAME. ONCE THIS FOG CLEARS...ABUNDANT SUNSHINE AND FURTHER WARMING ALOFT IS EXPECTED TO ALLOW TEMPERATURES TO RISE ABOVE 70F ACROSS THE SOUTH-CENTRAL DESERTS ON MONDAY AFTERNOON. AS FAR AS THE REST OF THE WEEK IS CONCERNED...MODEL GUIDANCE REMAINS VERY CONSISTENT IN CALLING FOR DRY AND WARMER CONDITIONS THROUGH THE ENTIRE WEEK...AND INTO NEXT WEEKEND...AS A STRONG UPPER LEVEL HIGH PRESSURE RIDGE STEADILY BUILDS INTO THE DESERT SOUTHWEST. AS THE RIDGE BUILDS...THERE WILL BE PERIODS OF HIGH CLOUDS SPREADING THROUGH THE RIDGE AND ACROSS THE DESERTS...BUT OVERALL WE SHOULD SEE MOSTLY SUNNY DAYS AND MOSTLY CLEAR NIGHTS. HIGH TEMPS ARE FORECAST TO CLIMB INTO THE MID TO UPPER 70S BY TUESDAY...THEN RISE FURTHER AND INTO THE UPPER 70S TO LOW 80S ACROSS THE WARMER DESERTS BY FRIDAY. IF THE WARMER EURO MODEL IS RIGHT...H5 HEIGHTS ARE FORECAST TO RISE IN EXCESS OF 585DM OVER THE SOUTHWEST AZ AND SERN CA DESERTS BY THIS WEEKEND...WHICH WOULD ALLOW HIGH TEMPS TO REACH INTO THE MID TO UPPER 80S ACROSS THE WARMER LOWER DESERTS. AT THIS POINT...HAVE JUST GONE WITH A MODEL BLEND...WHICH IS STILL PUSHING LOWER DESERT HIGHS INTO THE LOW TO MID 80S. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL... SHORT TERM: MOSTLY CLEAR SKIES WILL PREVAIL TONIGHT. SFC WINDS HAVE ALREADY TURNED E/SE AT KPHX (AND LIGHT AND VARIABLE ELSEWHERE) AND WILL MAINTAIN THESE HEADINGS THROUGH THE NIGHT WITH SPEEDS 3-5KT OR LESS. MONDAY MORNING: POTENTIAL STILL EXISTS FOR SOME FOG AROUND PHOENIX TERMINALS MONDAY MORNING...HOWEVER SHORT TERM HIGH RESOLUTION MODEL TRENDS SUGGEST FAR MORE LIMITED COVERAGE...AND DENSE FOG STAYING SOUTH OF THE METRO AREA. STILL MODERATE CONFIDENCE OF BRIEF PERIOD OF MVFR VSBY IN SE MARICOPA COUNTY (INCLUDING KPHX)...WITH FAR LESS CONFIDENCE OF LOWER CATEGORIES. MOST LIKELY TIMING WOULD BE IN THE 11Z-15Z TIME FRAME. OTHERWISE...EAST WINDS 3-6KT WILL PREVAIL INTO MONDAY AFTERNOON...THOUGH SOMEWHAT STRONGER WINDS UP TO 12KT WILL BE POSSIBLE IN A 1500-2000FT LAYER. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA WITH ONLY OCCASIONAL HIGH CIRRUS CLOUDS THROUGH MONDAY AFTERNOON. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE UNDER A WEAK PRESSURE GRADIENT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... TUESDAY THROUGH SATURDAY... WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS FOLLOWING THE TYPICAL DIURNAL PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...MO/PERCHA/CB AVIATION...MO/ FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS TUCSON AZ
235 PM MST SAT JAN 31 2015 .SYNOPSIS...A STORM SYSTEM CONTINUED TO BRING VALLEY RAIN AND MOUNTAINTOP SNOW THIS AFTERNOON...BUT THIS ACTIVITY WILL DIMINISH THIS EVENING AND TONIGHT. MINOR FLOODING AND ELEVATED FLOWS IN WASHES AND STREAMS WILL REMAIN A CONCERN THROUGH TONIGHT. THE MOST SIGNIFICANT SNOWFALL WILL BE ACROSS THE HIGHEST PEAKS...ABOVE 7500 FEET. EXPECT MUCH COOLER DAYTIME TEMPERATURES THIS WEEKEND. DRY CONDITIONS WITH A WARMING TREND WILL THEN OCCUR DURING THE UPCOMING WEEK. && .DISCUSSION...A STORM SYSTEM TRACKING SOUTHEAST OVER NORTHERN BAJA INTO NORTHWEST MEXICO WILL CONTINUE TO BRING PERIODS OF RAIN AND HIGH ELEVATION SNOW TO SOUTHEAST ARIZONA THROUGH EARLY SUNDAY. LATEST MODELS SUGGESTED THAT MUCH OF THIS PRECIPITATION WILL BE DIMINISHING THIS EVENING INTO TONIGHT AS THE SYSTEM TRACKS FARTHER SOUTHEAST OF THE AREA. THE HRRR SOLUTIONS INDICATE THAT THE CONVECTIVE SHOWERS DEVELOPING EARLY THIS AFTERNOON WILL DISSIPATE RAPIDLY AFTER SUNDOWN. THAT SAID...WILL KEEP RATHER HIGH POP VALUES AND THE WINTER STORM WARNING GOING...THEN TAPER OFF POP VALUES AFTER 03Z SUNDAY THROUGH 12Z SUNDAY. THE MAIN CONCERN WILL SHIFT FROM HEAVY MOUNTAINTOP SNOWFALL AND ELEVATED FLOWS IN NORMALLY DRY WASHES AND STREAMS TO DEVELOPING FOG LATER TONIGHT AND SUNDAY MORNING. DENSE FOG WAS REPORTED THIS MORNING IN SPOTS...ESPECIALLY AROUND CASA GRANDE WHERE THE VISIBILITY DROPPED TO 1/4 OF A MILE AT TIMES. A REPEAT OF THIS FOG WILL LIKELY BE MORE WIDESPREAD TONIGHT AS SKIES BEGIN TO CLEAR FROM NORTHWEST TO SOUTHEAST ACROSS THE AREA. NOT SURE HOW DENSE OR WHERE THE FOG WILL BE AT THIS TIME...SO WILL NOT POST AN ADVISORY ON THE AFTERNOON FORECAST PACKAGE. MODELS TRACK THE STORM SYSTEM WELL SOUTH OF THE REGION BY SUNDAY AFTERNOON WITH A RIDGE OF HIGH PRESSURE BUILDING INTO THE SOUTHWESTERN UNITED STATES BEHIND IT. THE MEDIUM RANGE MODELS KEEP THE STORM TRACK NORTH OF THE REGION THIS COMING WEEK. THAT SAID...THE FORECAST WILL CALL FOR DRY CONDITIONS ALONG WITH A WARMING TREND. HIGH TEMPERATURES WILL PEAK ABOUT 8 TO 10 DEGREES ABOVE NORMAL BY THE MIDDLE OF THIS COMING WEEK. FOR TUCSON...THE NORMAL HIGH THIS TIME OF YEAR IS AROUND 68 DEGREES. && .AVIATION...VALID THRU 02/00Z. PERIODS OF VALLEY RAIN AND HIGH ELEVATION MOUNTAIN SNOW ABOVE 7K FT AGL WILL CONTINUE INTO THIS EVENING...BEFORE TAPERING OFF OVERNIGHT INTO SUNDAY MORNING FROM NORTHWEST TO SOUTHEAST. THERE IS A SLIGHT CHANCE OF -TSRA ACROSS MUCH OF THE AREA THIS AFTERNOON INTO EARLY EVENING. CLOUD DECKS OF 2-3K FT AGL ARE LIKELY IN SHOWERS AND THUNDERSTORMS. OUTSIDE OF PRECIPITATION...EXPECT BKN-OVC CLOUDS AT 3-6K FT AGL. WINDS WILL MAINLY BE LESS THAN 10 KTS. DEPENDING ON CLOUD COVERAGE LATE TONIGHT...COULD SEE SOME PATCHY FOG BUT CONFIDENCE TOO LOW TO INCLUDE IN TERMINAL FORECASTS. OTHERWISE...IMPROVING CONDITIONS SUNDAY WITH DIMINISHING CLOUD COVERAGE. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FIRE WEATHER...EXPECT PERIODS OF VALLEY RAIN AND MOUNTAIN SNOW INTO THIS EVENING ALONG WITH WITH A FEW RUMBLES OF THUNDER AS A LOW PRESSURE SYSTEM MOVES ACROSS THE AREA. A FEW LINGERING SHOWERS WILL OCCUR MAINLY EAST TO SOUTH OF TUCSON EARLY SUNDAY. DRY CONDITIONS WILL RETURN SUNDAY AFTERNOON AND LAST THROUGH THE UPCOMING WORK WEEK. 20-FT WINDS THIS AFTERNOON WILL GENERALLY BE ELY-SLY AT 5-15 MPH. SOME EASTERLY WINDS ARE EXPECTED THURSDAY NIGHT INTO FRIDAY WITH A FEW HIGHER GUSTS POSSIBLE. OTHERWISE...TYPICAL DIURNAL WIND TRENDS FOR MUCH OF THE UPCOMING WEEK. && .TWC WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 5 PM MST TODAY FOR AZZ510>512-514. && $$ VISIT US ON FACEBOOK...TWITTER...YOUTUBE...AND AT WEATHER.GOV/TUCSON
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
213 PM MST SAT JAN 31 2015 .SYNOPSIS... AN EXITING LOW PRESSURE SYSTEM WILL BRING LINGERING RAIN CHANCES INTO EARLY TONIGHT TO THE EAST AND SOUTHWEST OF THE PHOENIX AREA. AREAS OF FOG...POTENTIALLY DENSE ACROSS NORTHERN PINAL COUNTY...WILL BE POSSIBLE LATE TONIGHT THROUGH SUNDAY MID MORNING DUE TO ABUNDANT LOW LEVEL MOISTURE AND CLEARING SKIES. HIGH PRESSURE WILL QUICKLY PUSH IN STARTING SUNDAY BRINGING CLEARING SKIES...DRYING CONDITIONS...AND WARMER TEMPERATURES. THE DRY CONDITIONS WILL PERSIST THROUGH THE NEXT WEEK WHILE A SLOW WARMING TREND ALLOWS FOR HIGHS REACHING NEAR 80 ACROSS THE LOWER DESERTS BY NEXT FRIDAY. && .DISCUSSION... THE LATEST SATELLITE AND UPPER HEIGHT ANALYSIS SHOWS THE UPPER TROUGH STARTING TO PICK UP SOME SPEED MOVING TO THE SOUTHEAST. TWO DISTINCT CIRCULATION CENTERS CONTINUE TO BE EVIDENT ON WATER VAPOR IMAGERY...ONE THAT IS QUICKLY WEAKENING AS IT MOVES INTO SOUTHERN CALIFORNIA AND ANOTHER WELL SOUTH OF THE AREA...CENTERED NEAR 29.7N/114.2W. THE SOUTHERN VORTICITY MAX IS STILL HELPING TO BRING SCATTERED SHOWERS ACROSS SOUTHEAST AND SOUTH-CENTRAL ARIZONA...WHILE A FEW MESO-VORTICIES CAN BE SEEN WITHIN RADAR IMAGERY...ONE OVER SOUTHERN MARICOPA COUNTY AND TWO OTHERS OVER SOUTHERN PINAL COUNTY. AREAS OF SHOWERS...SOME PRODUCING MODERATE RAIN AT TIMES...ARE FOCUSED NEAR THESE MESO-VORTICIES...WHILE MORE WIDELY ISOLATED SHOWERS HAVE BEEN MOVING WESTWARD ACROSS NORTHWEST MARICOPA COUNTY IN AN AREA OF SLIGHT ENHANCED INSTABILITY FROM SOME PEAKS OF SUN. THE LATEST HRRR AND WRF4KM HI-RES DATA SHOWS SHOWERS LASTING THROUGH MID AFTERNOON BEFORE GRADUALLY DIMINISHING BY EARLY EVENING. THIS SEEMS LIKE A VERY REASONABLE SOLUTION AS THE LARGE SCALE TROUGH CONTINUES TO DRIFT SOUTHEASTWARD OUT OF THE AREA AND WE SHOULD SEE ANY OVERLAYING LARGE SCALE ASCENT MOVE OUT OF THE CWA. ONCE SHOWERS END SOMETIME THIS EVENING...FOCUS THEN TURNS TOWARD THE POTENTIAL FOR FOG TONIGHT AND SUNDAY MORNING. THE SETUP FOR FOG IS NOT QUITE IDEAL AS WE SHOULD HAVE SOME LINGERING LOW STRATUS HANGING AROUND THROUGH FOR THE FIRST OF TONIGHT. HOWEVER...VERY MOIST SURFACE CONDITIONS WITH SURFACE DEW POINTS IN THE LOW TO MID 50S AND LIGHT WINDS SHOULD DEFINITELY ALLOW FOR SOME FOG FORMATION ACROSS THE AREA BY 12Z SUNDAY. MODEL RH FIELDS SHOW DRY AIR WORKING IN ALOFT FROM THE NORTH AFTER MIDNIGHT...BUT BOUNDARY LAYER CONDITIONS WILL REMAIN MOIST THROUGH SUNDAY AND POTENTIALLY MONDAY MORNING. THE POTENTIAL FOR WIDESPREAD FOG AND ANY DENSE FOG WILL MOSTLY RELY ON HOW MUCH CLEARING HAPPENS TONIGHT. CONFIDENCE IS HIGH THAT WE WILL SEE FOG IN AT LEAST LOW LYING AND RURAL AREAS ACROSS MARICOPA AND ESPECIALLY PINAL COUNTY...BUT STILL NOT VERY CONFIDENT ON THE EXTENT OF ANY FOG IN THE PHOENIX METRO AREA AND FOR ANY DENSE FOG POTENTIAL. SKIES WILL EVENTUALLY CLEAR OUT BY NOON SUNDAY IF THEY DIDN/T ALREADY...AND WITH RIDGING AND DRYING ALOFT MOVING IN FROM THE NORTH...WE WILL BEGIN TO SEE SOME WARMING. WE SHOULD SEE NEAR NORMAL HIGHS FOR SUNDAY AND THEN A FEW MORE DEGREES FOR MONDAY. THE PACIFIC RIDGE WILL STAY TO OUR WEST THROUGH THE MIDDLE OF THE WEEK GIVING US 500MB HEIGHTS GENERALLY BETWEEN 574-576DM...BUT MODELS THEN SHIFT THE RIDGE OVERHEAD BY LATE IN THE WEEK POINTING AT HEIGHTS NEARING 580DM. THIS WILL TRANSLATE INTO A NICE WARM-UP WITH LOWER DESERT HIGHS APPROACHING 80S DEGREES BY NEXT THURSDAY AND FRIDAY. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL...SCATTERED SHOWERS CONTINUE TO ROTATE EASTWARD ACROSS THE GREATER PHX AREA AT THIS HOUR...WITH HAVE RESULTED IN CIGS VARYING BETWEEN 3K FT AND 7 KT FT AT THE TERMINALS THIS AFTERNOON...WITH VISIBILITIES DROPPING BRIEFLY DOWN TO AS LOW AS 5SM IN THE HEAVIER SHOWERS. THE LATEST HI-RES MODEL RUNS ARE CONSISTENT WITH EARLIER RUNS...GRADUALLY DIMINISHING THIS SHOWER ACTIVITY THROUGH THE REMAINDER OF THE AFTERNOON AND EARLY EVENING AS THE UPPER LOW CONTINUES TO SLIDE TO THE SOUTH...AND AWAY FROM OUR REGION...WITH SHOWER ACTIVITY PRETTY MUCH ENDING AROUND/SHORTLY AFTER SUNSET. MID-LEVEL CLOUD LAYERS ARE THEN EXPECTED TO PERSIST THROUGH MUCH OF TONIGHT. FOG COULD BE A PROBLEM BY MORNING DUE TO A COMBINATION OF LIGHT WINDS AND AMPLE LOW-LEVEL MOISTURE. HOWEVER...THE AFOREMENTIONED MID-LEVEL CLOUDINESS WILL,LIKELY KEEP OVERNIGHT LOW TEMPS UP A BIT...WHICH SHOULD KEEP ANY FOG THAT ACTUALLY FORMS FROM BECOMING TOO DENSE. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... DRIER AIR MOVING INTO THE REGION FROM THE NORTH IS EXPECTED TO ALLOW SKIES TO CLEAR AT BOTH TERMINALS THROUGH THE EVENING AND OVERNIGHT HOURS...WITH MAINLY CLEAR SKIES EXPECTED ON SUNDAY. NORTHERLY TO NORTHWESTERLY WINDS ARE EXPECTED AT BOTH TERMINALS THROUGH THE TAF PERIOD...GRADUALLY DIMINISHING AS THE SFC PRESSURE GRADIENT RELAXES. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... MONDAY THROUGH FRIDAY... DRIER AND SIGNIFICANTLY WARMER WEATHER IS EXPECTED...AS HIGH PRESSURE BEGINS BUILDING BACK INTO THE REGION. HIGH TEMPERATURES IN THE LOWER DESERTS WILL START OUT NEAR 70 ON MONDAY AND GRADUALLY CLIMB TO AROUND 80 BY FRIDAY. LOW LEVEL MOISTURE WILL GRADUALLY DECREASE THROUGH THE PERIOD...WITH MINIMUM AFTERNOON HUMIDITIES DECREASING TO AROUND 25 PERCENT BY FRIDAY. WINDS ARE EXPECTED TO BE LIGHT AND VARIABLE FOR MOST OF THE FORECAST PERIOD. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...KUHLMAN AVIATION...PERCHA FIRE WEATHER...MCLANE
AREA FORECAST DISCUSSION
NWS SAN DIEGO CA
131 PM PST SAT JAN 31 2015 .SYNOPSIS... ISOLATED LIGHT SHOWERS FROM A WEAK LOW PRESSURE SYSTEM OVER THE SOUTHWEST STATES WILL MOSTLY END BY LATE THIS AFTERNOON...WITH PERHAPS A SHOWER OR TWO OCCURRING THIS EVENING FOR SAN DIEGO COUNTY. SURFACE HIGH PRESSURE OVER THE GREAT BASIN WILL CONTINUE TO BRING GUSTY NORTH TO NORTHEAST WINDS NEAR THROUGH AND BELOW THE CAJON PASS AND INTO THE COASTAL FOOTHILLS THROUGH EARLY SUNDAY MORNING. CLEARING SKIES AND WARMER WEATHER FOR SUNDAY AS HIGH PRESSURE ALOFT MOVES IN AND OFFSHORE FLOW WEAKENS. THE MARINE LAYER AND MOSTLY WEAK ONSHORE OR NEUTRAL FLOW WILL BRING NIGHT AND MORNING LOW CLOUDS AND PATCHY FOG FOR THE COAST AND PORTIONS OF THE VALLEYS SUNDAY NIGHT THROUGH THE END OF THE WORK WEEK. HIGH TEMPERATURES WILL BE AROUND SEASONAL NORMALS NEAR THE COAST TO AROUND 5 TO 10 DEGREES ABOVE NORMAL FOR INLAND AREAS. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... CURRENT RADAR IMAGERY SHOWS SOME LIGHT RETURNS OVER THE SAN BERNARDINO COUNTY MOUNTAINS...AND SAN DIEGO COUNTY...WITH SOME MODERATE SHOWERS OVER THE CENTRAL TO SOUTHERN SAN DIEGO COUNTY MOUNTAINS. THE 12Z MIRAMAR SOUNDING STILL SHOWED A MOIST ATMOSPHERE UP THROUGH 300 MB...WITH 0.95 INCHES OF PRECIPITABLE WATER. THIS MOISTURE...IN ADDITION TO A VORT MAX ASSOCIATED WITH A CLOSED LOW MOVING THROUGH THE AREA...IS WHAT CONTINUES TO BRING THESE ISOLATED SHOWERS TO THE REGION. THE LOCAL WRF AND HRRR ACTUALLY SHOW A COUPLE LIGHT SHOWERS CONTINUING INTO EARLY EVENING FOR CENTRAL AND SOUTHERN SAN DIEGO COUNTY...SO ADDED A 15 PERCENT CHANCE OF SHOWERS FOR THOSE AREAS FOR THE EARLY TO MID EVENING HOURS. ANY ADDITIONAL RAINFALL TODAY SHOULD BE VERY LIGHT...MOSTLY 0.01 OR LESS...WITH LOCAL 0.05 INCH AMOUNTS POSSIBLE. THE SNOW LEVEL WILL CONTINUE AT AROUND 7000 FEET THIS AFTERNOON...WITH ONLY LIGHT SNOWFALL ABOVE THAT ELEVATION POSSIBLE TODAY INTO THIS EVENING. SURFACE WIND-FLOW WILL START TO TURN OFFSHORE IN THE NORTH TO NORTHEAST DIRECTION LATE TODAY...AS SURFACE HIGH PRESSURE BUILDS OVER THE GREAT BASIN. HOWEVER...THE OFFSHORE WINDS DO NOT LOOK TO BE VERY STRONG...AS OFFSHORE PRESSURE GRADIENTS FROM SAN DIEGO TO TONOPAH ONLY INCREASE TO AROUND 6-8 MB...AND ONLY 2-3 MB FROM SAN DIEGO TO LAS VEGAS. SOME STATIONS ARE ALREADY REPORTING SOME 30-40 MPH GUSTS...BUT SPOTS THAT ARE RECEIVING THE WIND ARE MOSTLY GUSTING 15-25 MPH AT THE MOMENT. SINCE THE OFFSHORE FLOW WILL BE WEAK...LOCAL WRF INDICATES THAT SOME PATCHY MARINE LAYER STRATUS MAY DEVELOP IN THE COASTAL AREAS TONIGHT INTO SUNDAY MORNING. OFFSHORE FLOW WILL WEAKEN ON SUNDAY...AND AN UPPER LEVEL RIDGE WILL NUDGE INTO THE REGION AS THE TROUGH CONTINUES TO MOVE FAR SOUTH OF SOUTHERN CALIFORNIA. THIS WILL RESULT IN CLEARING SKIES AND WARMING WEATHER...WITH DAY-TIME HIGHS RISING SEVERAL DEGREES ABOVE NORMAL. MOSTLY WEAK ONSHORE TO NEUTRAL FLOW WILL THEN DEVELOP MONDAY THROUGH FRIDAY...UNDER CONTINUED RIDGING ALOFT...RESULTING IN FAIR WEATHER WITH BETTER NIGHT AND MORNING STRATUS/FOG COVERAGE FOR THE COAST AND PORTIONS OF THE VALLEYS. THERE WILL ALSO BE CONTINUED WARMING WITH DAY-TIME HIGHS RISING TO 5-10 DEGREES ABOVE NORMAL BY TUESDAY. TEMPERATURES WILL BE NEAR NORMAL AT THE COAST DUE TO THE MARINE LAYER. OCCASIONAL HIGH CLOUDS PASSING OVER THE AREA WILL MAKE FOR PARTLY CLOUDY SKIES AT TIMES. && .AVIATION... 312130Z...COAST/VALLEYS...MULTIPLE SCT-BKN CLOUD LAYERS AOA 3500 FT MSL THROUGH THIS EVENING. PATCHY LOW CLOUDS AND FOG REDEVELOPING AFTER 01/03Z ALONG THE COAST WITH CIGS 800-1500 FT MSL LIKELY AT KSAN AND KCRQ...LESS LIKELY AT KSNA. AREAS OF 3-5 SM IN BR POSSIBLE WITHIN 10 SM OF THE COAST. FORECAST CONFIDENCE IN COVERAGE AND CIG HEIGHTS IS MODERATE. CIGS AND VIS EXPECTED TO CLEAR BY MID-MORNING SUNDAY. MTS/DESERTS...NORTHERLY WINDS 15-20 KT WITH SFC GUSTS UP TO 40 KT WILL OCCUR ALONG THE RIDGES OF THE SAN BERNARDINO MTNS...BELOW THE CAJON PASS...NORTHERN COACHELLA VALLEY...AND THROUGH THE CANYONS OF THE SANTA ANA MTNS. WINDS GRADUALLY DECREASING THROUGH EARLY SUNDAY MORNING...THOUGH REMAINING WEAKLY OFFSHORE TO THE NORTH. OTHERWISE...SCT CLOUDS AOA 10000 FT MSL THROUGH SUNDAY MORNING. && .MARINE... 130 PM....SLIGHT CHANCE OF MAINLY LIGHT SHOWERS OVER THE INNER COASTAL WATERS THROUGH THIS EVENING. OTHERWISE...NO HAZARDOUS MARINE WEATHER IS EXPECTED THROUGH WEDNESDAY. && .SKYWARN... SKYWARN ACTIVATION IS NOT REQUESTED. HOWEVER WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER CONDITIONS. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...NONE. PZ...NONE. && $$ PUBLIC...HARRISON AVIATION/MARINE...23
AREA FORECAST DISCUSSION
NWS CHARLESTON SC
542 AM EST SAT JAN 31 2015 .SYNOPSIS... HIGH PRESSURE WILL PUSH SOUTH INTO THE AREA TODAY. THE HIGH WILL SHIFT INTO THE ATLANTIC SUNDAY...WHILE A WEAK COASTAL TROUGH DEVELOPS AND LIFTS NORTH AHEAD OF A COLD FRONT PASSING OVER THE AREA MONDAY. HIGH PRESSURE WILL THEN RETURN TO THE REGION BY TUESDAY...BEFORE SHIFTING OFFSHORE AHEAD OF ANOTHER STORM SYSTEM APPROACHING FROM THE GULF OF MEXICO BY LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... THE ONLY CHANGE MADE FOR THE SUNRISE UPDATE WAS TO INCREASE CLOUD COVER ACROSS SOUTHEAST GEORGIA TODAY. SATELLITE SHOWS A THICK PLUME OF HIGH-LEVEL MOISTURE MOVING QUICKLY ACROSS NORTHERN ALABAMA INTO NORTHWEST GEORGIA. THE LATEST RAP RH PROGNOSTICATIONS SHOW SOME OF THIS ACTIVITY REACHING SOUTH OF THE SAVANNAH RIVER LATER TODAY. THE REST OF THE FORECAST STILL LOOKS ON TRACK. HIGH PRESSURE WILL EXTEND ACROSS THE REGION TODAY AS MID/UPPER- LEVEL HEIGHTS BUILD ALOFT. EXPECT ANOTHER QUIET DAY FOR THE COASTAL EMPIRE AND LOWCOUNTRY GIVEN THIS REGIME. A BAND OF THIN CIRRUS IS MOVING ACROSS THE FAR SOUTHERN PORTIONS OF THE FORECAST AREA THIS MORNING. THESE CLOUDS ARE FORECAST TO PUSH SOUTH AND DIMINISH OVER THE NEXT COUPLE OF HOURS AS THE SUPPORTING 125 KT 250 HPA JET STREAM SHIFTS NORTH IN RESPONSE TO MEAN 850-200 HPA RIDGING. HIGHS WILL RANGE FROM THE LOWER-MID 50S NORTH AREAS TO THE MID- UPPER 50S CENTRAL AND SOUTHERN AREAS. NORTH/NORTHEAST WINDS THIS MORNING WILL GRADUALLY VEER ONSHORE THIS AFTERNOON AS THE CENTER OF THE SURFACE HIGH SHIFTS SOUTH. THE RESULTING ONSHORE FLOW WILL KEEP COASTAL LOCATIONS RATHER CHILLY WITH HIGHS LIKELY BEING LIMITED TO THE UPPER 40S/NEAR 50 RIGHT ALONG THE BEACHES. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/... TONIGHT...DEEP LAYERED RIDGING WILL REMAIN FIRMLY ENTRENCHED ACROSS THE SOUTHEAST U.S. TONIGHT WITH THE CENTER OF THE SURFACE HIGH FORECAST TO SHIFT SLOWLY OFF THE SOUTH CAROLINA COAST. THICK CIRRUS ASSOCIATED WITH A SHORTWAVE ROUNDING THE WESTERN FLANKS OF THE MEAN RIDGE AXIS WILL SPREAD QUITE A BIT OF HIGH CLOUDINESS ACROSS THE REGION AFTER MIDNIGHT. 31/00Z NSSL-WRF/GEM SIMULATED CLOUD PRODUCTS SUGGEST SKIES WILL GENERALLY REMAIN PARTLY TO MOSTLY CLOUDY. THE INCREASED CLOUD COVER COUPLED WITH WEAK 925-850 HPA WARM AIR ADVECTION WILL YIELD A WARMER NIGHT THAN THIS MORNING WITH LOWS RANGING FROM THE LOWER 30S INTERIOR SOUTHEAST SOUTH CAROLINA TO THE MID-UPPER 30S ELSEWHERE...EXCEPT THE LOWER 40S ALONG THE BEACHES AND BARRIER ISLANDS. SUNDAY...SURFACE HIGH PRESSURE WILL BE STEADILY SLIPPING FARTHER INTO THE ATLANTIC DURING THE MORNING HOURS...JUST DOWNSTREAM OF A DEEPENING LOW PRESSURE SYSTEM MOVING INTO THE TENNESSEE VALLEY BY MIDDAY. A WEAK COASTAL TROUGH WILL DEVELOP ALONG THE PERIPHERY OF THE RETREATING HIGH PRESSURE EARLY...SHIFTING TOWARD THE COAST AND LIFTING NORTH AS A WARM FRONTAL FEATURE LATE IN THE DAY. THE FORECAST AREA WILL LIKELY REMAIN BETWEEN MARINE SHOWERS TO THE EAST/NORTHEAST AND CONVECTION TO THE WEST ASSOCIATED WITH THE APPROACHING COLD FRONT. HAVE THUS WAITED UNTIL LATE AFTERNOON TO INDICATE ISOLATED TO SCATTERED SHOWERS SPREADING INTO THE FORECAST AREA. DESPITE THICKENING CLOUD COVER...TEMPERATURES WILL BECOME QUITE WARM FOR EARLY FEBRUARY WITHIN SOLID SOUTHERLY FLOW. EXPECT TEMPERATURES TO PEAK IN THE MID TO UPPER 60S AWAY FROM THE LOCALLY COOLER COAST. SUNDAY NIGHT AND MONDAY...A ROBUST UPPER TROUGH WILL SWEEP TOWARD THE EAST COAST AND ASSIST IN THE PROGRESSION OF THE COLD FRONT THROUGH THE FORECAST AREA DURING THE MORNING HOURS MONDAY. LOW TEMPERATURES SUNDAY NIGHT WILL BE QUITE MILD IN THE 50S DUE TO THE COMBINED EFFECTS OF INSULATING CLOUD COVER AND A WELL MIXED ATMOSPHERE WITHIN SOLID SOUTHWEST FLOW. THE HIGHEST RAIN COVERAGE IS EXPECTED FROM SUNSET SUNDAY THROUGH EARLY MONDAY MORNING...WHEN BEST FORCING FOR CONVERGENCE ALONG THE FRONTAL ZONE AND THE NOSE OF A 130 KT UPPER JET MOVES INTO THE AREA. DUE TO SOME SLIGHT TIMING DIFFERENCES IN THE MODELS...WILL KEEP RAIN CHANCES JUST BELOW 80 PERCENT...WHICH IS STILL A FAIRLY HIGH CONFIDENCE FORECAST. THE FRONT WILL LIKELY BE OFFSHORE BY MONDAY AFTERNOON...WITH DRIER AIR BEGINNING TO FILTER INTO THE REGION AHEAD OF BUILDING HIGH PRESSURE. RAIN CHANCES WILL THUS END FROM WEST TO EAST AS THE DAY PROGRESSES. HIGH TEMPERATURES MONDAY AFTERNOON WILL BE WITHIN A FEW DEGREES OF SEASONAL NORMALS...RANGING FROM THE UPPER 50S FAR INLAND TO THE LOW 60S EAST. IT SHOULD BE NOTED THAT BREEZY TO GUSTY WINDS WILL DEVELOP SUNDAY NIGHT THROUGH MONDAY AFTERNOON...AS AN IMPRESSIVE 50 KT LOW LEVEL JET MOVES ACROSS THE AREA OVERNIGHT...AND A LARGE PRESSURE GRADIENT DEVELOPS IN THE WAKE OF THE FRONT DURING THE DAYTIME HOURS. WEST/NORTHWEST WINDS COULD PEAK AT 20 TO 30 MPH. MONDAY NIGHT AND TUESDAY...THE PRESSURE GRADIENT WILL BEGIN TO WEAKEN AS SURFACE HIGH PRESSURE MOVES INTO THE MID ATLANTIC AND SOUTHEAST STATES...EVENTUALLY BECOMING LOCATED ALONG THE COASTLINE BY TUESDAY AFTERNOON. A MUCH COOLER AIR MASS WILL HAVE MOVED INTO THE REGION...AND EXPECT NOTABLY COLDER LOW TEMPERATURES MONDAY NIGHT IN THE UPPER 20S INLAND TO THE LOW 30S CLOSER TO THE COAST. HIGH TEMPERATURES ON TUESDAY WILL BE NEARLY 10 DEGREES COOLER THAN THE PREVIOUS DAY...SUPPRESSED IN THE LOW TO MID 50S WITHIN SOLID NORTHEAST FLOW. LAKE WINDS...GUSTY CONDITIONS ARE EXPECTED ALONG THE LAKE SHORE OF LAKE MOULTRIE MONDAY...HOWEVER MIXING WILL BE RESTRICTED SOMEWHAT OVER THE BULK OF THE LAKE WATERS. AS A RESULT...THERE REMAINS SOME UNCERTAINTY AS TO WHETHER A LAKE WIND ADVISORY WILL BE REQUIRED. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... TRANSIENT SURFACE HIGH PRESSURE WILL MOVE INTO THE ATLANTIC TUESDAY NIGHT. A COASTAL TROUGH WILL ONCE AGAIN DEVELOP ALONG THE PERIPHERY OF THE ATLANTIC HIGH ON WEDNESDAY...WHILE A SOUTHERN STREAM SHORTWAVE DEVELOPS FAR TO THE WEST ACROSS TEXAS AND SUPPORTS THE DEVELOPMENT OF A SURFACE LOW IN THE GULF OF MEXICO. ALTHOUGH THE INITIAL SHORTWAVE WILL DAMPEN LATE WEDNESDAY...THE SURFACE LOW WILL CONTINUE TO TAKE SHAPE AND MOVE EAST ACROSS THE GULF. NUMERICAL MODEL SOLUTIONS DIVERGE QUITE NOTABLY REGARDING THE STRENGTH OF THE LOW PRESSURE WAVE AND THE PRESENCE OF ADDITIONAL SHORTWAVE ENERGY DIVING INTO THE GULF COAST STATES OR SOUTHEAST LATE THURSDAY INTO FRIDAY. AS A RESULT...CONFIDENCE IN FORECAST DETAILS BECOMES RATHER LOW FOR THE LATE WEEK PERIOD. AFTER A PERIOD OF DRY WEATHER EARLY IN THE WEEK...HAVE REINTRODUCED RAIN CHANCES BY WEDNESDAY TO ACCOUNT FOR MARINE SHOWERS PROGRESSING ONSHORE FROM THE COASTAL TROUGH. HAVE THEN INCREASED RAIN COVERAGE WEDNESDAY NIGHT INTO THURSDAY...AS MEDIUM RANGE MODELS ARE IN GENERAL AGREEMENT THAT SOME DEGREE OF RAIN WILL BE AFFECTING THE FORECAST AREA DURING THIS TIME FRAME. MODEL SOLUTIONS THAT INDICATE THE SECOND WAVE OF UPPER LEVEL ENERGY LATE THURSDAY INTO FRIDAY MAINTAIN RAIN COVERAGE ACROSS THE REGION ACCORDINGLY...YET WILL CAP RAIN POTENTIAL NO HIGHER THAN SLIGHT CHANCE THROUGH FRIDAY UNTIL MODELS COME INTO BETTER AGREEMENT. HAVE INDICATED RAIN CHANCES FALLING BELOW 10 PERCENT BY SATURDAY...WITH ANY COASTAL LOW SYSTEM LIKELY LIFTING AWAY BY THE WEEKEND. HIGH TEMPERATURES WILL BE IN THE UPPER 50S TO LOWER 60S WEDNESDAY AND THURSDAY AFTERNOONS...BEFORE A NOTABLE COOLING TREND OCCURS ON THE BACK SIDE OF THE LOW PRESSURE SYSTEM FRIDAY AND SATURDAY. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... VFR WITH LIGHT WINDS THROUGH THE PERIOD. EXTENDED AVIATION OUTLOOK...VFR CONDITIONS WILL PREVAIL UNTIL SUNDAY NIGHT INTO MONDAY MORNING...WHEN MVFR OR POSSIBLY LOWER CONDITIONS ARE LIKELY DUE TO A PASSING COLD FRONT. BREEZY CONDITIONS AND/OR WIND SHEAR IS ALSO LIKELY SUNDAY NIGHT/MONDAY. && .MARINE... TODAY...EXPECT BOTH WINDS AND SEAS TO DIMINISH TODAY AS HIGH PRESSURE SHIFTS SOUTH. GUSTY NORTH WINDS THIS MORNING WILL SETTLE INTO THE 5-10 KT RANGE OVER THE CHARLESTON COUNTY WATERS AND CHARLESTON HARBOR THIS AFTERNOON WITH 10-15 KT ELSEWHERE. SEAS WILL AVERAGE 2-3 FT NEARSHORE WATERS AND 3-4 FT OFFSHORE WATERS. TONIGHT...EAST WINDS WILL BACK VEER SOUTHEAST OVERNIGHT WITH WINDS GENERALLY REMAINING LESS THAN 10 KT. SEAS WILL AVERAGE 1-2 FT NEARSHORE WATERS WITH 2-3 FT OFFSHORE WATERS. SUNDAY AND MONDAY...SURFACE HIGH PRESSURE WILL CONTINUE TO TRACK INTO THE ATLANTIC SUNDAY. THE PRESSURE GRADIENT WILL THEN TIGHTEN BETWEEN THE ATLANTIC HIGH AND AN UPSTREAM LOW AND TRAILING COLD FRONT SWEEPING THROUGH THE MARINE ZONES MONDAY. COLD ADVECTION THAT SUPPORTS MIXING INTO A NOTABLE 40 TO 50 KT LOW LEVEL JET WILL EASILY ALLOW CONDITIONS TO REACH SOLID SMALL CRAFT ADVISORY THRESHOLDS...WITH A RISK FOR POSSIBLE GALES ACROSS THE CHARLESTON COUNTY WATERS AND OFFSHORE GEORGIA ZONES. ALTHOUGH CONFIDENCE IS NOT HIGH ENOUGH TO INCLUDE EXPLICITLY IN THE FORECAST...WILL CONTINUE TO NOTE THE SMALL POTENTIAL FOR SEA FOG SUNDAY EVENING IF THE INCREASE IN WINDS ARE DELAYED...AS WELL AS A RISK FOR SOME STRONGER THUNDERSTORMS OUT NEAR THE GULF STREAM IN ADVANCE OF THE COLD FRONT. TUESDAY THROUGH WEDNESDAY...A TRANSIENT HIGH PRESSURE WEDGE WILL PREVAIL AS LOW PRESSURE EVENTUALLY DEVELOPS IN THE WEST/NORTHWEST GULF AND A COASTAL TROUGH ATTEMPTS TO FORM NEARBY. LATEST PROGNOSIS IS THAT CONDITIONS REMAIN BELOW THE ADVISORY CRITERIA DURING THIS TIME. && .CHS WATCHES/WARNINGS/ADVISORIES... GA...NONE. SC...NONE. MARINE...NONE. && $$ ST/WMS
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
334 PM CST SAT JAN 31 2015 ...UPDATED FOR LONG TERM DISCUSSION... .SHORT TERM...(TONIGHT AND SUNDAY) ISSUED AT 232 PM CST SAT JAN 31 2015 AN UPPER LEVEL TROUGH, LOCATED OVER WESTERN MONTANA EARLIER THIS MORNING, WILL MOVE ACROSS WESTERN KANSAS DURING THE OVERNIGHT HOURS. AS THIS SYSTEM APPROACHES FROM THE NORTHWEST THIS EVENING...850MB TO 700MB FRONTOGENESIS WILL DEVELOP ACROSS SOUTHWEST KANSAS. THIS AREA OF FRONTOGENISIS WILL MOVE VERY LITTLE BETWEEN 03Z AND 06Z SUNDAY BASED ON THE 12Z NAM AND THIS AREA OF ENHANCED FORCING WILL BRING WIDESPREAD PRECIPITATION BACK TO SOUTHWEST KANSAS EARLY TONIGHT. AT THIS TIME BASED ON THE TOP DOWN APPROACH THE PRECIPITATION THIS EVENING WILL BE MAINLY LIQUID, HOWEVER AS COLDER AIR BEGINS TO MOVE INTO SOUTHWEST TOWARDS MIDNIGHT THIS WIDESPREAD LIGHT RAIN WILL BEGIN TO MIX WITH SNOW AFTER 03Z. AREA MORE FAVORABLE FOR THE RAIN TO SNOW CHANGE OVER BEFORE MIDNIGHT WILL BE MAINLY ACROSS NORTH CENTRAL AND WEST CENTRAL KANSAS. AFTER MIDNIGHT THE AREA OF 850MB TO 700MB FRONTOGENESIS WILL MOVE QUICKLY MOVE SOUTHEAST AS THE UPPER LEVEL THE UPPER LEVEL TROUGH CROSSES WESTERN KANSAS BETWEEN 06Z AND 12Z SUNDAY. AS THIS UPPER LEVEL TROUGH PASSES THE PRECIPITATION WILL BEGIN TAPER OFF FROM NORTHWEST TO SOUTHEAST. AS COLD AIR SPREADS ACROSS WESTERN KANSAS LATE TONIGHT THE RAIN IS EXPECTED TO MIX WITH OR BRIEFLY CHANGE TO SNOW BEFORE ENDING ACROSS SOUTHWEST AND SOUTH CENTRAL KANSAS. GIVEN A QUICKER RAIN TO SNOW CHANGE OVER ACROSS NORTH CENTRAL AND PORTIONS OF WEST CENTRAL KANSAS THERE WILL BE A CHANCE FOR UP TO ONE INCH OF SNOW OVERNIGHT NORTH OF HIGHWAY 50. FURTHER SOUTH ANY ACCUMULATION IS EXPECTED TO BE LIGHT AND MAINLY ON GRASSY AND ELEVATED SURFACES. STRONG NORTH WINDS WILL DEVELOP LATE TONIGHT BEHIND A COLD FRONT THAT WILL BE CROSSING WESTERN KANSAS BETWEEN 06Z AND 12Z SUNDAY. TIMING OF THIS COLD FRONT IS STILL UNCLEAR, HOWEVER ALL MODELS DO AGREE THAT STRONG WINDS WILL DEVELOP BEHIND THIS COLD FRONT LATE TONIGHT AND EARLY SUNDAY. GUSTY NORTH WINDS OF 25 TO 35 MPH WILL BE LIKELY EARLY SUNDAY BASED ON THE TIGHT SURFACE PRESSURE GRADIENT AND THE FORECAST MEAN MIXED LAYER WINDS BEHIND THIS FRONT. TEMPERATURES OVERNIGHT WILL NOT FALL VERY QUICKLY UNTIL THE FRONTAL PASSAGE AFTER MIDNIGHT. TEMPERATURE WILL THEN DROP BASED MAGNITUDE OF THE COLD AIR ADVECTION FORECAST TOWARDS 12Z SUNDAY. AT THIS TIME WILL STAY CLOSE TO THE LATEST GUIDANCE GIVEN THE UNCERTAINTY OF THE FRONTAL PASSAGE LATER TONIGHT. ON SUNDAY SKIES WILL CLEAR BUT BASED ON THE 900MB TO 850MB TEMPERATURE TRENDS THE HIGHS ON SUNDAY WILL STRUGGLE TO CLIMB INTO THE MID 20S IN NORTH CENTRAL KANSAS AND NEAR THE OKLAHOMA BORDER THE HIGHS WILL BE MAINLY IN THE LOW TO MID 30S. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 231 PM CST SAT JAN 31 2015 THE MID TO UPPER LEVEL FLOW WILL BE NORTHWESTERLY THROUGH THE WEEK, WITH UPPER LEVEL RIDGING NEAR THE WEST COAST AND TROUGHING OVER THE EASTERN UNITED STATES. HOWEVER, ONE PARTICULAR UPPER LEVEL FEATURE THAT WILL PLAY A LARGE ROLE IN DAY TO DAY WEATHER IS A STRONG SHORTWAVE TROUGH ENTERING THE NORTHERN PLAINS ON TUESDAY AND THEN PROGRESSING INTO THE NORTHEAST BY THURSDAY. AHEAD OF THIS FEATURE, LEE TROUGHING WILL RESULT IN MILDER TEMPERATURES MONDAY AND TUESDAY WITH HIGHS WARMING INTO THE 60S BY TUESDAY. MUCH COLDER AIR IS EXPECTED BY WEDNESDAY INTO EARLY THURSDAY IN THE WAKE OF THIS FEATURE AS A SMALL AREA OF ARCTIC HIGH PRESSURE PUSHES SOUTHWARD INTO KANSAS. HIGHS MAY NOT MAKE IT OUT OF THE 20S ACROSS MUCH OF SOUTHWEST KANSAS WEDNESDAY. THE ONLY CHANCE OF PRECIPITATION IN THE FORM OF SNOW, ALBEIT SLIGHT, WILL BE WEDNESDAY AND WEDNESDAY NIGHT AS MID LEVEL FRONTOGENESIS DEVELOPS ACROSS WESTERN KANSAS. ANOTHER WARM UP CAN BE EXPECTED THURSDAY AND FRIDAY AS THE MID LEVEL FLOW BECOMES MORE ZONAL, WITH WEAK RIDGING OVER THE ROCKIES AND SURFACE TROUGHING IN THE LEE OF THE ROCKIES. HIGH TEMPERATURES OUGHT TO RISE INTO THE 40S TO LOWER 50S BY THURSDAY, WITH 60S AND POSSIBLY EVEN LOWER 70S FRIDAY. AFTER FRIDAY, A SHORTWAVE TROUGH OVER THE ROCKIES IS EXPECTED TO PROGRESS EASTWARD AND AMPLIFY INTO A LARGE UPPER LEVEL STORM SYSTEM OVER THE SOUTHEASTERN UNITED STATES BY SUNDAY AND MONDAY (FEB 8TH-9TH). ANY PRECIPITATION WITH THIS FEATURE SHOULD BE WELL OFF TO THE EAST, WITH TEMPERATURES NEAR TO ABOVE SEASONAL AVERAGES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1105 AM CST SAT JAN 31 2015 LIGHT RAIN WILL CONTINUE TO TAPER OFF FROM SOUTHWEST TO NORTHEAST EARLY THIS AFTERNOON AS GUSTY SOUTH WINDS DECREASE INTO THE 10 TO 15 KNOT RANGE BY LATE DAY. THE CEILINGS WILL IMPROVE SOME, HOWEVER BASED ON THE 12Z BUFR SOUNDINGS AND THE LATEST HRRR CEILINGS ARE ONLY EXPECTED TO INCREASE INTO THE 1500FT TO 2000FT AGL LEVEL BY LATE DAY. A COLD FRONT WILL CROSS SOUTHWEST KANSAS EARLY TONIGHT. HRRR HAS THE FRONT PASSING HYS AND GCK BETWEEN 02Z AND 05Z AND DDC NEAR OR SHORTLY AFTER 06Z. AS THIS FRONT PASSES THE WINDS WILL SHIFT TO THE NORTHWEST AND THEN INCREASE TO NEAR 20 KNOTS. THERE WILL ALSO BE A CHANCE FOR A BRIEF PERIOD OF RAIN OR SNOW BEHIND THIS COLD FRONT AS AN UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS. AFTER 12Z SUNDAY WIND SPEEDS WILL INCREASE TO AROUND 25 KNOTS AS LOW CLOUDS GIVE WAY TO CLEARING SKIES. && .PRELIMINARY POINT TEMPS/POPS... DDC 27 30 14 44 / 70 10 0 0 GCK 27 31 14 49 / 70 0 0 0 EHA 30 36 19 56 / 60 0 0 0 LBL 31 36 18 50 / 60 10 0 0 HYS 23 26 11 44 / 80 10 0 0 P28 30 33 14 39 / 70 20 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...FINCH AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
235 PM CST SAT JAN 31 2015 ...UPDATED SHORT TERM DISCUSSION... .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 232 PM CST SAT JAN 31 2015 AN UPPER LEVEL TROUGH, LOCATED OVER WESTERN MONTANA EARLIER THIS MORNING, WILL MOVE ACROSS WESTERN KANSAS DURING THE OVERNIGHT HOURS. AS THIS SYSTEM APPROACHES FROM THE NORTHWEST THIS EVENING...850MB TO 700MB FRONTOGENESIS WILL DEVELOP ACROSS SOUTHWEST KANSAS. THIS AREA OF FRONTOGENISIS WILL MOVE VERY LITTLE BETWEEN 03Z AND 06Z SUNDAY BASED ON THE 12Z NAM AND THIS AREA OF ENHANCED FORCING WILL BRING WIDESPREAD PRECIPITATION BACK TO SOUTHWEST KANSAS EARLY TONIGHT. AT THIS TIME BASED ON THE TOP DOWN APPROACH THE PRECIPITATION THIS EVENING WILL BE MAINLY LIQUID, HOWEVER AS COLDER AIR BEGINS TO MOVE INTO SOUTHWEST TOWARDS MIDNIGHT THIS WIDESPREAD LIGHT RAIN WILL BEGIN TO MIX WITH SNOW AFTER 03Z. AREA MORE FAVORABLE FOR THE RAIN TO SNOW CHANGE OVER BEFORE MIDNIGHT WILL BE MAINLY ACROSS NORTH CENTRAL AND WEST CENTRAL KANSAS. AFTER MIDNIGHT THE AREA OF 850MB TO 700MB FRONTOGENESIS WILL MOVE QUICKLY MOVE SOUTHEAST AS THE UPPER LEVEL THE UPPER LEVEL TROUGH CROSSES WESTERN KANSAS BETWEEN 06Z AND 12Z SUNDAY. AS THIS UPPER LEVEL TROUGH PASSES THE PRECIPITATION WILL BEGIN TAPER OFF FROM NORTHWEST TO SOUTHEAST. AS COLD AIR SPREADS ACROSS WESTERN KANSAS LATE TONIGHT THE RAIN IS EXPECTED TO MIX WITH OR BRIEFLY CHANGE TO SNOW BEFORE ENDING ACROSS SOUTHWEST AND SOUTH CENTRAL KANSAS. GIVEN A QUICKER RAIN TO SNOW CHANGE OVER ACROSS NORTH CENTRAL AND PORTIONS OF WEST CENTRAL KANSAS THERE WILL BE A CHANCE FOR UP TO ONE INCH OF SNOW OVERNIGHT NORTH OF HIGHWAY 50. FURTHER SOUTH ANY ACCUMULATION IS EXPECTED TO BE LIGHT AND MAINLY ON GRASSY AND ELEVATED SURFACES. STRONG NORTH WINDS WILL DEVELOP LATE TONIGHT BEHIND A COLD FRONT THAT WILL BE CROSSING WESTERN KANSAS BETWEEN 06Z AND 12Z SUNDAY. TIMING OF THIS COLD FRONT IS STILL UNCLEAR, HOWEVER ALL MODELS DO AGREE THAT STRONG WINDS WILL DEVELOP BEHIND THIS COLD FRONT LATE TONIGHT AND EARLY SUNDAY. GUSTY NORTH WINDS OF 25 TO 35 MPH WILL BE LIKELY EARLY SUNDAY BASED ON THE TIGHT SURFACE PRESSURE GRADIENT AND THE FORECAST MEAN MIXED LAYER WINDS BEHIND THIS FRONT. TEMPERATURES OVERNIGHT WILL NOT FALL VERY QUICKLY UNTIL THE FRONTAL PASSAGE AFTER MIDNIGHT. TEMPERATURE WILL THEN DROP BASED MAGNITUDE OF THE COLD AIR ADVECTION FORECAST TOWARDS 12Z SUNDAY. AT THIS TIME WILL STAY CLOSE TO THE LATEST GUIDANCE GIVEN THE UNCERTAINTY OF THE FRONTAL PASSAGE LATER TONIGHT. ON SUNDAY SKIES WILL CLEAR BUT BASED ON THE 900MB TO 850MB TEMPERATURE TRENDS THE HIGHS ON SUNDAY WILL STRUGGLE TO CLIMB INTO THE MID 20S IN NORTH CENTRAL KANSAS AND NEAR THE OKLAHOMA BORDER THE HIGHS WILL BE MAINLY IN THE LOW TO MID 30S. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 324 AM CST SAT JAN 31 2015 IN THE LONGER TERM THE GREATEST CHALLENGE WILL BE TEMPERATURES, BOTH SPATIALLY AND THE MAGNITUDE. EARLY SUNDAY THE MOST LIKELY TIMING OF THE NORTHERN BRANCH OF THE WESTERLIES SHORT WAVE TROUGH WILL BE EXITING MY SOUTHEAST COUNTIES. THERE COULD BE LINGERING LIGHT PRECIPITATION (MOST LIKELY LIGHT SNOW) AROUND BARBER COUNTY EARLY SUNDAY MORNING. ELSEWHERE, SKIES SHOULD BE GRADUALLY CLEARING IN PRESENCE OF STRONG COLD AIR ADVECTION. THE AIR BEHIND THE FRONT THAT MOVES THROUGH EARLIER WILL BE ARCTIC IN NATURE. HOWEVER, MY AREA WILL BE ON THE FRINGE OF THE AIRMASS. STILL, TEMPERATURES DURING THE DAY SUNDAY WILL NOT GET ABOVE FREEZING ALONG THE I-70 CORRIDOR BUT MAY STILL WARM A LITTLE AROUND ELKHART. BY MONDAY ANOTHER FAST MOVING S/WV TROUGH IN THE NORTHERN BRANCH OF THE WESTERLIES WILL HELP LOWER PRESSURES ALONG THE LEE OF THE ROCKIES AND SUBSEQUENTLY PRODUCE A SOUTHERLY FLOW NEAR THE SURFACE. WARMING WILL BE MOST PREVALENT NEAR THE COLORADO BORDER. BUT, HOW FAR EAST THE MIXING OCCURS AND RESULTANT WARMING IS IN QUESTION. MY EASTERN COUNTIES COULD VERY WELL STAY ENTRENCHED IN THE RETREATING ARCTIC AIR UNTIL LATE AFTERNOON. TEMPERATURES ON MONDAY HAVE SOME BUST POTENTIAL. YET ANOTHER FAST MOVING S/WV TROUGH IN THE NORTHERN BRANCH WESTERLIES WILL HAVE A SURFACE RESPONSE IN THE FORM OF ANOTHER ARCTIC AIRMASS FRONT THAT SHOULD ARRIVE LATE TUESDAY OR WEDNESDAY. TIMING IS UNCERTAIN BUT MID-WEEK LOOKS MOST LIKELY. IN ADDITION, THERE SHOULD BE ENOUGH DYNAMICS AND BAROCLINICITY TO PROMOTE SOME PRECIPITATION, ALTHOUGH MOST LIKELY LIGHT (AND IN THE FORM OF FROZEN). ANOTHER WARM-UP IS EXPECTED LATER IN THE WEEK AS UPPER HEIGHTS BUILD A LITTLE AND THE WESTERLIES RETREAT A BIT NORTH.&& .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1105 AM CST SAT JAN 31 2015 LIGHT RAIN WILL CONTINUE TO TAPER OFF FROM SOUTHWEST TO NORTHEAST EARLY THIS AFTERNOON AS GUSTY SOUTH WINDS DECREASE INTO THE 10 TO 15 KNOT RANGE BY LATE DAY. THE CEILINGS WILL IMPROVE SOME, HOWEVER BASED ON THE 12Z BUFR SOUNDINGS AND THE LATEST HRRR CEILINGS ARE ONLY EXPECTED TO INCREASE INTO THE 1500FT TO 2000FT AGL LEVEL BY LATE DAY. A COLD FRONT WILL CROSS SOUTHWEST KANSAS EARLY TONIGHT. HRRR HAS THE FRONT PASSING HYS AND GCK BETWEEN 02Z AND 05Z AND DDC NEAR OR SHORTLY AFTER 06Z. AS THIS FRONT PASSES THE WINDS WILL SHIFT TO THE NORTHWEST AND THEN INCREASE TO NEAR 20 KNOTS. THERE WILL ALSO BE A CHANCE FOR A BRIEF PERIOD OF RAIN OR SNOW BEHIND THIS COLD FRONT AS AN UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS. AFTER 12Z SUNDAY WIND SPEEDS WILL INCREASE TO AROUND 25 KNOTS AS LOW CLOUDS GIVE WAY TO CLEARING SKIES. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1105 AM CST SAT JAN 31 2015 LIGHT RAIN WILL CONTINUE TO TAPER OFF FROM SOUTHWEST TO NORTHEAST EARLY THIS AFTERNOON AS GUSTY SOUTH WINDS DECREASE INTO THE 10 TO 15 KNOT RANGE BY LATE DAY. THE CEILINGS WILL IMPROVE SOME, HOWEVER BASED ON THE 12Z BUFR SOUNDINGS AND THE LATEST HRRR CEILINGS ARE ONLY EXPECTED TO INCREASE INTO THE 1500FT TO 2000FT AGL LEVEL BY LATE DAY. A COLD FRONT WILL CROSS SOUTHWEST KANSAS EARLY TONIGHT. HRRR HAS THE FRONT PASSING HYS AND GCK BETWEEN 02Z AND 05Z AND DDC NEAR OR SHORTLY AFTER 06Z. AS THIS FRONT PASSES THE WINDS WILL SHIFT TO THE NORTHWEST AND THEN INCREASE TO NEAR 20 KNOTS. THERE WILL ALSO BE A CHANCE FOR A BRIEF PERIOD OF RAIN OR SNOW BEHIND THIS COLD FRONT AS AN UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS. AFTER 12Z SUNDAY WIND SPEEDS WILL INCREASE TO AROUND 25 KNOTS AS LOW CLOUDS GIVE WAY TO CLEARING SKIES. && .PRELIMINARY POINT TEMPS/POPS... DDC 27 30 14 44 / 70 10 0 0 GCK 27 31 14 49 / 70 0 0 0 EHA 30 36 19 56 / 60 0 0 0 LBL 31 36 18 50 / 60 10 0 0 HYS 23 26 11 44 / 80 10 0 0 P28 30 33 14 39 / 70 20 0 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...HUTTON AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1109 AM CST SAT JAN 31 2015 ...UPDATED SYNOPSIS AND AVIATION DISCUSSION... .SYNOPSIS... ISSUED AT 1105 AM CST SAT JAN 31 2015 AT 12Z SATURDAY A 500MB RIDGE AXIS EXTENDED FROM EASTERN TEXAS INTO KANSAS. A 500MB LOW LOCATED OVER WESTERN ARIZONA. FURTHER NORTH A 500MB TROUGH WAS LOCATED OVER WESTERN MONTANA WITH A 500MB BAROCLINIC ZONE EXTENDING FROM NORTHERN IDAHO TO NORTHWEST MISSOURI. AT THE 700MB AND 850MB LEVEL A SOUTH/SOUTHWEST FLOW WAS CONTINUING TO DRAW MOISTURE NORTHWARD ACROSS SOUTHWEST AND CENTRAL KANSAS INTO NORTHEASTERN NEBRASKA. 850MB TEMPERATURES THIS MORNING AT 12Z WERE -1C AT AMARILLO AND DODGE CITY AND -2C AT NORTH PLATTE AND TOPEKA. AN 850MB FRONT EXTENDED FROM EASTERN MONTANA TO WISCONSIN. THE SURFACE COLD FRONT THIS MORNING AT 12Z SATURDAY EXTENDED FROM NORTHERN IOWA, ACROSS NORTHERN NEBRASKA, INTO NORTHEAST WYOMING. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 210 AM CST SAT JAN 31 2015 MOSTLY CLOUDY SKIES WILL CONTINUE TODAY AS MOISTURE AND LIFT INCREASES ABOVE WESTERN KANSAS. THIS IS AS AN UPPER LEVEL LOW SPINS ABOVE THE BAJA REGION AND AN UPPER LEVEL SHORTWAVE MOVES SOUTH ACROSS THE NORTHERN ROCKIES AND NORTHERN PLAINS. PRECIPITATION CHANCES WILL CONTINUE THROUGHOUT THE DAY WITH THE BEST CHANCE OF MEASURABLE PRECIPITATION ALONG THE KS/OK BORDER AS WELL AS SOUTH CENTRAL KANSAS AND CENTRAL KANSAS. ANY PRECIPITATION THAT FALLS TODAY SHOULD REMAIN AS RAIN WITH THE EXCEPTION OF THE I-70 CORRIDOR THIS MORNING WHERE SNOW WILL BE POSSIBLE. WINDS WILL GENERALLY BE FROM THE SOUTH TODAY BECOMING BREEZY IN THE AFTERNOON. PRECIPITATION CHANCES END FROM NORTHWEST TO SOUTHEAST TONIGHT WITH CONTINUED MOSTLY CLOUDY SKIES. PRECIPITATION MAY MIX WITH OR CHANGE ALL OVER TO SNOW AS WE APPROACH SUNRISE. A COLD FRONT WILL MOVE THROUGH THE AREA OVERNIGHT SHIFTING WINDS TO MORE OF A NORTHERLY DIRECTION. HIGHS TODAY ARE EXPECTED TO ONLY REACH INTO THE LOW TO MID 40S WITH LOWS TONIGHT RANGING FROM THE MID 20S ACROSS THE I-70 CORRIDOR TO LOWER 30S ACROSS THE KS/OK BORDER. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 324 AM CST SAT JAN 31 2015 IN THE LONGER TERM THE GREATEST CHALLENGE WILL BE TEMPERATURES, BOTH SPATIALLY AND THE MAGNITUDE. EARLY SUNDAY THE MOST LIKELY TIMING OF THE NORTHERN BRANCH OF THE WESTERLIES SHORT WAVE TROUGH WILL BE EXITING MY SOUTHEAST COUNTIES. THERE COULD BE LINGERING LIGHT PRECIPITATION (MOST LIKELY LIGHT SNOW) AROUND BARBER COUNTY EARLY SUNDAY MORNING. ELSEWHERE, SKIES SHOULD BE GRADUALLY CLEARING IN PRESENCE OF STRONG COLD AIR ADVECTION. THE AIR BEHIND THE FRONT THAT MOVES THROUGH EARLIER WILL BE ARCTIC IN NATURE. HOWEVER, MY AREA WILL BE ON THE FRINGE OF THE AIRMASS. STILL, TEMPERATURES DURING THE DAY SUNDAY WILL NOT GET ABOVE FREEZING ALONG THE I-70 CORRIDOR BUT MAY STILL WARM A LITTLE AROUND ELKHART. BY MONDAY ANOTHER FAST MOVING S/WV TROUGH IN THE NORTHERN BRANCH OF THE WESTERLIES WILL HELP LOWER PRESSURES ALONG THE LEE OF THE ROCKIES AND SUBSEQUENTLY PRODUCE A SOUTHERLY FLOW NEAR THE SURFACE. WARMING WILL BE MOST PREVALENT NEAR THE COLORADO BORDER. BUT, HOW FAR EAST THE MIXING OCCURS AND RESULTANT WARMING IS IN QUESTION. MY EASTERN COUNTIES COULD VERY WELL STAY ENTRENCHED IN THE RETREATING ARCTIC AIR UNTIL LATE AFTERNOON. TEMPERATURES ON MONDAY HAVE SOME BUST POTENTIAL. YET ANOTHER FAST MOVING S/WV TROUGH IN THE NORTHERN BRANCH WESTERLIES WILL HAVE A SURFACE RESPONSE IN THE FORM OF ANOTHER ARCTIC AIRMASS FRONT THAT SHOULD ARRIVE LATE TUESDAY OR WEDNESDAY. TIMING IS UNCERTAIN BUT MID-WEEK LOOKS MOST LIKELY. IN ADDITION, THERE SHOULD BE ENOUGH DYNAMICS AND BAROCLINICITY TO PROMOTE SOME PRECIPITATION, ALTHOUGH MOST LIKELY LIGHT (AND IN THE FORM OF FROZEN). ANOTHER WARM-UP IS EXPECTED LATER IN THE WEEK AS UPPER HEIGHTS BUILD A LITTLE AND THE WESTERLIES RETREAT A BIT NORTH.&& .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1105 AM CST SAT JAN 31 2015 LIGHT RAIN WILL CONTINUE TO TAPER OFF FROM SOUTHWEST TO NORTHEAST EARLY THIS AFTERNOON AS GUSTY SOUTH WINDS DECREASE INTO THE 10 TO 15 KNOT RANGE BY LATE DAY. THE CEILINGS WILL IMPROVE SOME, HOWEVER BASED ON THE 12Z BUFR SOUNDINGS AND THE LATEST HRRR CEILINGS ARE ONLY EXPECTED TO INCREASE INTO THE 1500FT TO 2000FT AGL LEVEL BY LATE DAY. A COLD FRONT WILL CROSS SOUTHWEST KANSAS EARLY TONIGHT. HRRR HAS THE FRONT PASSING HYS AND GCK BETWEEN 02Z AND 05Z AND DDC NEAR OR SHORTLY AFTER 06Z. AS THIS FRONT PASSES THE WINDS WILL SHIFT TO THE NORTHWEST AND THEN INCREASE TO NEAR 20 KNOTS. THERE WILL ALSO BE A CHANCE FOR A BRIEF PERIOD OF RAIN OR SNOW BEHIND THIS COLD FRONT AS AN UPPER LEVEL TROUGH CROSSES THE CENTRAL HIGH PLAINS. AFTER 12Z SUNDAY WIND SPEEDS WILL INCREASE TO AROUND 25 KNOTS AS LOW CLOUDS GIVE WAY TO CLEARING SKIES. && .PRELIMINARY POINT TEMPS/POPS... DDC 41 26 33 14 / 90 60 10 0 GCK 43 25 35 14 / 30 50 0 0 EHA 44 28 40 19 / 30 40 0 0 LBL 42 29 38 18 / 90 50 10 0 HYS 39 24 27 11 / 90 70 10 0 P28 41 30 35 14 / 100 70 20 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...BURGERT SHORT TERM...HOVORKA_42 LONG TERM...HUTTON AVIATION...BURGERT
AREA FORECAST DISCUSSION
NWS DODGE CITY KS
1231 AM CST SAT JAN 31 2015 ...UPDATED AVIATION SECTION... .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 144 PM CST FRI JAN 30 2015 MOISTURE AND ISENTROPIC LIFT FROM I300 TO I308 APPEARS TO HAVE A DECENT HANDLE OF THE LIGHT PRECIPITATION CURRENTLY SPREADING NORTH ACROSS NORTHEAST NEW MEXICO AND THE PANHANDLE OF TEXAS. BASED ON 15Z AND 18Z VERIFICATION EARLIER TODAY WILL THEREFORE BE USING THE THE I300 TO I308 LEVEL OVERNIGHT AS GUIDE FOR PRECIPITATION CHANCES AND TIMING OF THIS PRECIPITATION AS IMPROVING MOISTURE AND ISENTROPIC LIFT DEVELOPS ACROSS SOUTHWEST KANSAS. AT THIS TIME BASED ON THE 12Z NAM AND LATEST RAP THE BETTER OPPORTUNITY FOR WIDESPREAD PRECIPITATION OVER WESTERN KANSAS WILL BE FROM 03Z AND 09Z SATURDAY. AFTER 09Z ISENTROPIC DOWNGLIDE BEGINS TO DEVELOPS ACROSS FAR WESTERN KANSAS SO THIS PRECIPITATION TO BEGIN TO TAPER OFF NEAR THE COLORADO BORDER, OR AT LEAST BECOME MORE WIDELY SCATTERED, EARLY FRIDAY MORNING. AT THIS TIME MODEL SOUNDINGS ALONG WITH THE TOP DOWN APPROACH FOR PRECIPITATION TYPE BOTH SUPPORT MAINLY A COLD RAIN EVENT FOR ALL BUT PORTIONS OF NORTH CENTRAL AND FAR WESTERN KANSAS. IN THE NORTH CENTRAL AND FAR WESTERN KANSAS THE ATMOSPHERE WILL BECOME COLD ENOUGH FOR THE RAIN TO MIX WITH, OR BRIEFLY CHANGE OVER TO SNOW AROUND DAYBREAK SATURDAY. BASED ON THE WARM SURFACE TEMPERATURES AND RAINFALL OVERNIGHT LITTLE IF ANY SNOW ACCUMULATION IS EXPECTED SHOULD A BRIEF PERIOD OF SNOW DEVELOPS. AREAS OF FOG CAN ALSO BE EXPECTED LATE TONIGHT BASED ON THE MOISTURE PROFILES NEAR THE SURFACE AND SOUTH SOUTHEASTERLY WIND AT 10 TO 15 MPH. ON THURSDAY SOME BREAKS OF SUN WILL BE POSSIBLE ACROSS PORTIONS OF WESTERN KANSAS EARLY IN THE DAY GIVEN THE ISENTROPIC DOWNGLIDE DEVELOPING IN THIS AREA. AS A RESULT HAVE FAVORED THE WARMER GUIDANCE FOR HIGHS SATURDAY AFTERNOON WEST OF HIGHWAY 283. FURTHER EAST MOISTURE AND WEAK ISENTROPIC LIFT WILL CONTINUE SO WILL FAVOR THE COOLER GUIDANCE GIVEN THE EXPECTED CLOUD COVER AND LIGHT PRECIPITATION. AT THIS TIME HIGHS ARE EXPECTED TO VARY FROM NEAR 40 IN SOUTH CENTRAL KANSAS TO MID 40S IN WEST CENTRAL KANSAS. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 307 PM CST FRI JAN 30 2015 CONFIDENCE REMAINS RELATIVELY HIGH THAT THE SYSTEM WILL BE TOO SLOW TO TURN COLD ENOUGH TO WARRANT A SIGNIFICANT ACCUMULATION OF SNOW SATURDAY NIGHT. THE LATEST NAM AND ECMWF RUNS MAINTAIN OUR AREA ON THE WARM SIDE OF THE SURFACE BOUNDARY UNTIL MID EVENING SATURDAY WHEN HE FRONT IS ABLE TO BE FORCED THROUGH THE CENTRAL HIGH PLAINS BY THE EXITING UPPER SYSTEM. EVENT HE IMMEDIATE POST FRONTAL AIR APPEARS TOO WARM FOR SNOW ACCUMULATION, AND TEMPERATURES MAY NOT FALL COLD ENOUGH ACROSS A LARGE ENOUGH PORTION OF THE AREA UNTIL SUNDAY MORNING WHEN THE UPPER STRETCHING AND DEFORMATION HAS BASICALLY CEASED. THE COLDEST AIR IN A FEW WEEKS SHOULD THEN BE NOTICED BY SUNDAY NIGHT AND EARLY MONDAY MORNING, AS STRONG SUBSIDENCE, DRIER AIR AND GOOD LONGWAVE RADIATIONAL COOLING OF A COLDER DRIER AIRMASS IS POSSIBLE. THE MOS OUTPUT FROM AT LEAST THE ECMWF AND NAM MODELS ARE THE COLDEST WITH POTENTIAL FOR EVEN SINGLE DIGITS OVER CENTRAL KANSAS EARLY MONDAY MORNING. THE CONSENSUS OF RAW MODEL OUTPUT WAS NOT FAR FROM THESE COLDER SOLUTION AS WELL, WHICH WAS USED AS THE OFFICIAL FORECAST. A STRONG WARMING TREND ON THE EAST SIDE OF AN UPPER RIDGE WILL BE NOTICED HEADING INTO MID WEEK, WITH TEMPERATURES LIKELY BACK INTO THE 60S BEFORE THE NEXT UPPER JET/SHORTWAVE/COLD FRONT AFFECT THE CENTRAL PLAINS LATE WEDNESDAY AND THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1229 AM CST SAT JAN 31 2015 OCCASIONAL MVFR CONDITIONS WILL BE POSSIBLE OVERNIGHT AS MOSTLY CLOUDY SKIES AND LIGHT RAIN SHOWERS FALL ACROSS WESTERN KANSAS. WINDS WILL GENERALLY BE FROM THE SOUTH AROUND 12 KNOTS. && .PRELIMINARY POINT TEMPS/POPS... DDC 44 31 36 13 / 60 60 10 0 GCK 46 31 37 13 / 50 50 0 0 EHA 44 33 40 21 / 50 50 0 0 LBL 44 34 41 17 / 60 60 10 0 HYS 42 26 29 10 / 50 60 0 0 P28 42 34 38 13 / 70 70 10 0 && .DDC WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...BURGERT LONG TERM...RUSSELL AVIATION...HOVORKA_42
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
911 PM EST SUN FEB 1 2015 .UPDATE... ISSUED AT 835 PM EST SUN FEB 1 2015 AS OF 8 PM...AN AREA OF LOW PRESSURE WAS CENTERED OVER EASTERN INDIANA WITH A STATIONARY FRONT EXTENDING EAST INTO THE MID ATLANTIC STATES WITH A COLD FRONT EXTENDING SOUTH JUST TO THE WEST OF THE INTERSTATE 65 CORRIDOR. A DRY SLOT EXTENDED FROM EASTERN OK NORTH AND NORTHEAST INTO SOUTHERN IL WITH RADAR RETURNS ACROSS KY EAST OF THIS AREA. A SFC TROUGH WHICH IS THE LEADING EDGE OF THE MUCH COLDER AIR EXTENDED WEST INTO SOUTHERN IL AND EASTERN MO.SOME SNOW IS ALSO FALLING NEAR AND BEHIND THE SFC TROUGH WHICH IS LOCATED IN ADVANCE OF THE UPPER LEVEL SHORTWAVE. TEMPERATURES HAVE RISEN FROM THE MID 30S TO UPPER 30S ON TOP OF BLACK MOUNTAIN IN THE WARM ADVECTION AHEAD OF THE COLD FRONT. THE BACK EDGE OF THE STEADIER SHOWERS IS ENTERING THE JKL CWA WITH ANOTHER AREA OF SHOWERS IN ADVANCE OF AND JUST BEHIND THE COLD FRONT. AS THE COLD FRONT WORKS EAST...WE EXPECT A RELATIVE LULL IN THE PRECIPITATION FOR A TIME IN MANY AREAS AFTER IT PASSES DURING THE OVERNIGHT UNTIL THE UPPER LEVEL TROUGH AND SFC TROUGH NEARS AND LAPSE RATES STEEPEN. ATTM...IT LOOKS LIKE THE ATMOSPHERE WILL BEGIN TO COOL TO COLD ENOUGH LEVELS FOR A MIX WITH OR CHANGEOVER TO SNOW OF ANY LINGERING SHOWERS JUST BEHIND THE COLD FRONT IN THE FAR NW GENERALLY BETWEEN 2 AND 5 AM. THE HIGHEST TERRAIN ABOVE 2500 FEET COULD ALSO CHANGEOVER DURING THAT TIME. SOMEWHAT MORE ORGANIZED SNOW SHOWERS ARE ANTICIPATED WITH THE SFC TROUGH AND IN ADVANCE OF THE SHORTWAVE AS THE COLDEST AIR WORKS IN ALOFT SHOULD ARRIVE OR DEVELOP AND ENHANCE AS IT INTERACTS WITH THE TERRAIN RISE AT THE ESCARPMENT IN OUR WESTERN OR NW CWA AROUND 6 OR 7 AM AND THEN GENERALLY TRANSLATE ACROSS THE AREA. ADDITIONAL LESS ORGANIZED SHOWERS OR RAIN OR SNOW OR A MIX MAY BE ONGOING AT THAT TIME AS WELL. RECENT MODEL GUIDANCE DOES NOT PROVIDE MUCH CONFIDENCE IN THIS EVOLUTION AS THERE ARE HINTS OF SNOW SHOWERS AS THE RELATIVELY STRONG SHORTWAVE MOSES THROUGH AND THE LOW HAS AN UPSLOPE COMPONENT. HOWEVER...HRR RUNS AND SHORT TERM GUIDANCE SUCH AS THE NAM AND THE RAP ARE NOT ALL THAT IMPRESSIVE. THE STRENGTH OF THE SHORTWAVE...ASSOCIATED LAPSE RATES AND UPSLOPE FLOW THOUGH ARGUE FOR GENERALLY HIGH CHANCE TO LIKELY POPS FOR THE NORTH AND SOUTHEAST FOR MONDAY MORNING. AT THIS TIME...WE PLAN TO NOT ADD ANY ADDITIONAL AREAS TO THE WSW. HOWEVER...UPSTREAM TRENDS WILL BE MONITORED ALONG WITH TIMING INTO THE NW COUNTIES WHICH ON AVERAGE SHOULD BE THE COLDEST DURING THE MORNING COMMUTE FOR POSSIBLE AREAL ADDITION TO THE WSW. IN ORDER TO ACCOUNT FOR THE HIGHER TERRAIN OF FONDE MTN AREA OF WESTERN BELL COUNTY WHICH SHOULD BE FAVORED IN THE NW UPSLOPE FLOW AND BETTER MATCH START TIMES TO MY SOUTH...WE HAVE STARTED THE WSW A COUPLE OF HOURS EARLIER FOR THE VA BORDER COUNTIES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 335 PM EST SUN FEB 1 2015 19Z SFC ANALYSIS SHOWS A RATHER DEEP AREA OF LOW PRESSURE MOVING ACROSS THE MISSISSIPPI RIVER INTO ILLINOIS. A COLD FRONT FROM THIS IS STRETCHED TO THE SOUTHWEST DOWN INTO TEXAS. AS THIS LOW PUSHES FURTHER INTO THE OHIO VALLEY...THE CORE OF ITS PCPN SHIELD IS NOW ENTERING EASTERN KENTUCKY WITH LIGHT TO MODERATE RAINS OVERSPREADING THE AREA. UNDER THICK CLOUDS AND THE ARRIVING RAINS...TEMPERATURES HAVE PEAKED THIS AFTERNOON WITH READINGS IN THE MID 40S TO LOWER 50S ACROSS THE AREA. DEWPOINTS...MEANWHILE...ARE COMING UP WITH THE ARRIVING RAINS AND NOW VARY FROM THE LOW TO MID 20S IN THE EAST AND THE UPPER 30S TO LOWER 40S TO THE WEST. WIND HAVE ALSO PICKED UP WITH THE ARRIVAL OF THE RAIN WITH GUSTS TO 20 TO 25 KTS FROM THE SOUTH OVER THE CUMBERLAND VALLEY AND 15 TO 20 KTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY WHIP A SHARP TROUGH THROUGH THE SOUTHERN APPALACHIANS BY MIDDAY MONDAY. IN THE NORTHWEST FLOW THAT FOLLOWS...A TRAILING SHORTWAVE WILL PASS THROUGH EASTERN KENTUCKY INTO EARLY TUESDAY MORNING...SEEN AS STRONGEST IN THE ECMWF WHEN COMPARED TO THE NAM12 AND GFS/GEM. HAVE MAINLY FOLLOWED A MODEL BLEND THROUGH MONDAY NIGHT WITH AN EMPHASIS ON THE HIGHER RESOLUTION DETAILS FROM THE NAM12 BEFORE LEANING MORE ON THE GFS AND NAM12 WITH THE TRAILING WAVE THROUGH TUESDAY MORNING. SENSIBLE WEATHER WILL FEATURE A GOOD SOAKING RAIN FOR EAST KENTUCKY THROUGH THE EVENING AND INTO THE OVERNIGHT ALONG WITH BREEZY CONDITIONS AS THE WRAPPED UP SFC LOW MOVES THROUGH. THE LOW PASSES TO THE EAST BY SUNRISE MONDAY WITH WINDS SWITCHING TO THE WEST AND INCREASING AS THE TIGHT GRADIENT ON THE LOW/S BACKSIDE EXITS THE AREA. IN ADDITION TO THE BREEZY CONDITIONS IN THE WAKE OF THE LOW...AN ARCTIC BOUNDARY WILL BRING IN MUCH COLDER AIR FROM WEST TO EAST ACROSS THE CWA BETWEEN 08 AND 13Z RESULTING IN A SWITCH OVER FOR ANY LINGERING PCPN TO SNOW. THE WINDS WILL BECOME MORE UPSLOPE WHILE THE SFC LOW FURTHER DEEPENS INTO MONDAY MORNING. THIS WILL ADD TO THE SNOW FALL FOR OUR FAR EASTERN COUNTIES WITH THE WINDS BLOWING THE SNOW AROUND KEEPING THE VIS LOW IN ANY SHOWERS. EXPECT THE SNOW TO BE WORST BETWEEN 11 AND 15Z FOR MOST OF THE AREA WITH LIGHT ACCUMULATIONS EXPECTED ASIDE FROM THE RIDGES AND LOCATIONS IN THE FAR EAST. ALONG THOSE PLACES NEAR THE VIRGINIA BORDER SOME HIGHER SNOW TOTALS WILL BE POSSIBLE WITH BETWEEN 2 AND 3 INCHES SEEN ON THE PEAKS ABOVE 2500 FEET AND UP TO 2 INCHES ON THE LOWER RIDGES WHILE VALLEYS GENERALLY PICK UP AN INCH OR LESS. FINALLY...IN ADDITION TO THE SNOW AND WINDS...THE COLD AIR COULD MOVE IN QUICK ENOUGH...TRAILING THE RAINS AND LIMITED DRY SLOTTING TO RESULT IN ICY CONDITIONS ON AREA ROADS. FOR THIS REASON...WILL HAVE AN SPS OR WINTER WEATHER ADVISORY OUT FOR THE ENTIRE AREA...HITTING THE EAST PROGRESSIVELY HARDER FOR AMOUNTS AND IMPACTS. OUR VIRGINIA BORDER COUNTIES WILL HAVE AN ADVISORY FOR SNOW GOING UNTIL 23Z WHILE TO THE WEST THE ADVISORY WILL RUN THROUGH 19Z WITH LESSER TOTALS. THE SNOW TAPERS OFF FROM WEST TO EAST MONDAY AFTERNOON WITH CAA SENDING TEMPS DOWN INTO THE TEENS MOST PLACES BY DAWN TUESDAY...THOUGH LOW CLOUDS WILL LIKELY KEEP READINGS FROM COMPLETELY BOTTOMING OUT FOR EASTERN PARTS OF THE AREA. USED THE BCCONSSHORT FOLLOWED BY THE SUPERBLEND AS A STARTING POINT FOR TEMPERATURES...DEWPOINTS...AND WINDS THROUGH TUESDAY MORNING. MADE ONLY MINOR ADJUSTMENTS TO WINDS AND TEMPERATURES TO ACCOUNT FOR THE TERRAIN EFFECTS OF THE CAA WINDS LATE TONIGHT INTO MONDAY MORNING. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS GUIDANCE THROUGH MONDAY AFTERNOON OWING TO THE TENDENCY FOR THE MODEL/MOS GUIDANCE TO UNDER DO UPSLOPE SNOW SITUATIONS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 410 PM EST SUN FEB 1 2015 TUESDAY WILL START OUT WITH GENERALLY ZONAL FLOW ALOFT AND SURFACE HIGH PRESSURE IN PLACE. TEMPERATURES WILL WARM FROM THE PREVIOUS DAY WITH SURFACE WINDS BECOMING MORE SRLY AND SKIES CLEARING...THOUGH STILL EXPECTED TO BE A FEW DEGREES BELOW SEASONABLE NORMALS. A SHORTWAVE WILL BEGIN TO TRAVERSE ALONG A TROUGH AXIS WELL NORTH OF THE REGION...REACHING THE UPPER GREAT LAKES BY WEDNESDAY EVENING AND STRENGTHENING AS IT SHOOTS OFF TO THE SE AND ACROSS THE EASTERN PORTION OF KY. THIS COURSE OF ACTION...INCLUDING THE AMPLITUDE AND TIMING...IS VERY MUCH A RESULT OF WHICH MODEL IS CORRECT. AS OF NOW...THERE IS STILL QUITE A BIT OF DISAGREEMENT BETWEEN THE GFS AND ECMWF...WHICH LEADS TO LOW CONFIDENCE ON THE RESULTING SURFACE FEATURES. THE GFS CONTINUES TO BE THE STRONGEST WITH THE SYSTEM...SHOWING A 1009MB LOW PRESSURE SYSTEM MOVING ACROSS NEW ENGLAND WEDNESDAY EVENING. THE ECMWF IS IN A SIMILAR LOCATION FOR THE LOW...BUT IS SLIGHTLY WEAKER AT 1013MB AS OF THE 12Z RUN. A COLD FRONT WILL EXTEND SOUTHWEST OF THIS LOW...AND BRING FRONTAL PRECIPITATION TO MUCH OF THE OHIO VALLEY WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR THE GFS...AND SOMEWHAT LATER WEDNESDAY NIGHT THROUGH THURSDAY AFTERNOON FOR THE ECMWF AND GEM. REGARDLESS...THIS WILL BE A QUICK HITTING SYSTEM...WITH MUCH OF THE MOISTURE FALLING ALONG OR JUST BEHIND THE FRONTAL PASSAGE. IF THIS HOLDS TRUE...WINDS WILL MAKE A QUICK SHIFT TO THE N AND BEGIN PULLING IN MUCH COLDER AIR AROUND THE TIME THE PRECIPITATION STARTS. THIS WILL QUICKLY DROP TEMPS BELOW FREEZING...SO EXPECT ANY PRECIP THAT FALLS TO BE MAINLY IN THE FORM OF SNOW...WITH MAYBE A SMALL AMOUNT OF RAIN AT THE ONSET. HIGHS ON THURSDAY ARE ONLY EXPECTED TO REACH THE UPPER 20S TO AROUND 30. DRY AIR WILL THEN QUICKLY WORK IN AND CUT OFF ANY REMAINING SNOW POTENTIAL SOMETIME THURSDAY AFTERNOON. DO NOTE...GIVEN THE DISCREPANCIES BETWEEN THE MODELS...THE TIMING OF ONSET AND DEPARTURE IS LIKELY TO CHANGE. THIS WILL THEN LIKELY AFFECT THE SNOW TOTALS. AT THIS TIME...FORECASTING GENERALLY A HALF INCH OR LESS ACROSS THE CWA...WITH THE HIGHEST AMOUNTS IN THE SE WHERE SNOW WILL LINGER THE LONGEST AND SOME UPSLOPE FLOW WILL TAKE PLACE. AFTER THIS SYSTEM PASSES THROUGH THE REGION...UPPER LEVELS WILL SLOWLY TRANSITION BACK TO ZONAL FLOW. COLDER CANADIAN AIR FLOWING INTO THE REGION WILL EVENTUALLY GIVE WAY TO MORE SEASONABLE NORMS BY SATURDAY. HIGH PRESSURE WILL BE IN CONTROL THROUGH MUCH OF THE REMAINDER OF THE EXTENDED. OUR NEXT THREAT FOR PRECIP WILL OCCUR SOMETIME SATURDAY NIGHT/SUNDAY ON DAY 7 OF THE FORECAST AS MODELS HINT AT ANOTHER SHORTWAVE DEVELOPING OVER THE CENTRAL PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 739 PM EST SUN FEB 1 2015 CIGS INITIALLY WILL BE MAINLY IN THE MVFR RANGE OR FALL INTO THE VFR RANGE EARLY IN THE PERIOD. DETERIORATION TO IFR AND BELOW CONDITIONS ARE ANTICIPATED AFTER 06Z. THE RAIN WILL THEN CHANGE TO SNOW THROUGH ABOUT 13Z AS THE COLDER AIR MOVES IN WITH REDUCED VISIBILITY AND LOWER VIS BEING THE MAIN CONCERN. SOUTH TO SOUTHWEST WINDS WILL START SHIFTING TO THE WEST SOUTHWEST AND LATER TONIGHT TO THE WEST. GUSTS AS HIGH AS 25 KT WILL BE POSSIBLE THROUGH AT LEAST 18Z ON MONDAY AS THE SYSTEM MOVES ON THROUGH. CONDITIONS SHOULD IMPROVE BACK INTO THE MVFR RANGE BETWEEN 15Z AND 21Z IN MOST LOCATIONS. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM EST MONDAY FOR KYZ087- 088-118-120. WINTER WEATHER ADVISORY FROM 3 AM TO 2 PM EST MONDAY FOR KYZ086- 104-106>117-119. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...JMW AVIATION...JP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
959 PM CST SUN FEB 1 2015 .DISCUSSION... COLD FRONT HAS MOVED SOUTHEAST OF THE AREA WITH LARGE HIGH PRESSURE SYSTEM CENTERED OVER THE PLAINS MOVING SOUTH PROVIDING COLD AND MUCH DRIER AIR INTO THE FOUR STATE REGION. ONLY CHANGES TO THE ONGOING FORECAST WAS TO LOWER THE CLOUD COVER FOR MUCH OF THE REGION AND ADJUST THE DEW POINTS. WINDS WILL REMAIN ELEVATED TO NEAR AND ABOVE LAKE WIND CRITERIA FOR MUCH OF THE FORECAST AREA THROUGH THE EARLY MORNING MONDAY. WILL KEEP THE LAKE WIND ADVISORY IN EFFECT AS IS. /06/ && .PREV DISCUSSION... /ISSUED 547 PM CST SUN FEB 1 2015/ AVIATION... FOR THE 02/00Z TAFS...RAIN HAS MOVED SOUTH AND EAST OF THE TAF SITES AND POST-FRONTAL STRATOCU CONTINUES TO MOVE SEWD AS WELL AND IS GENERALLY SE OF A LINE FROM KLFK TO KMLU. ONCE THE STRATOCU DEPARTS...VFR CONDITIONS WILL PREVAIL. AFTER A BRIEF PERIOD OF CLEARING SKIES...A BAND OF MID LVL CLOUDS WILL MOVE ACROSS THE AREA THIS EVENING/TONIGHT FOLLOWED BY SKC CONDITIONS BY MONDAY AFTERNOON AS A DRY SFC HIGH PRESSURE BUILDS INTO THE REGION. NWLY WINDS WILL REMAIN GUSTY UNTIL DIMINISHING DURING THE DAYTIME HRS MONDAY. /09/ PREV DISCUSSION... /ISSUED 359 PM CST SUN FEB 1 2015/ DISCUSSION... THE SCT CONVECTION HAS RAPIDLY MOVED E ACROSS LOWER E TX/NCNTRL LA THIS AFTERNOON ALONG THE COLD FRONT...WHICH EXTENDS FROM THE MS RIVER ALONG THE AR/MS BORDER SW TO LLQ...TO ELD...TO JUST N OF A IER...TO S OF A LFK LINE AS OF 21Z. THE HRRR CONTINUES TO HAVE THE BEST HANDLE ON THE ONGOING CONVECTION...WHICH SHOULD COMPLETELY EXIT THE AREA BY/SHORTLY AFTER 00Z. BEHIND THE FRONT...GUSTY NW WINDS CONTINUE TO EXPAND SE...WITH GUSTS TO 25KTS COMMON ACROSS EXTREME NE TX/SE OK/SW AR. THE SHORT TERM PROGS DO AGREE ON A 6MB PRESSURE DIFFERENCE FROM W TO E ACROSS THE CWA THIS EVENING...AND GIVEN THIS...HAVE EXPANDED THE LAKE WIND ADVISORY THROUGH 10Z MONDAY TO COVER THE REMAINDER OF THE CWA EXCEPT THE LOWER SAM RAYBURN COUNTRY OF DEEP E TX AS WELL AS THE SRN PARISHES OF NCNTRL LA...WHERE WINDS SHOULD BE A BIT MORE MARGINAL. STRONG COLD ADVECTION BEHIND THE FRONT SHOULD RESULT IN FREEZING TEMPS OVER ALL BUT THE SRN AND ERN SECTIONS OF THE REGION...DESPITE THE POST-FRONTAL STRATOCU OVER CNTRL/ERN OK NOT CLEARING UNTIL LATE TONIGHT ACROSS SE OK/SW AR/NCNTRL LA. CANADIAN SFC RIDGING WILL BEGIN TO SETTLE S ACROSS THE SRN PLAINS MONDAY...THUS WEAKENING THE GRADIENT BY DAYBREAK. HOWEVER...EVEN WITH ABUNDANT SUNSHINE...TEMPS WILL STRUGGLE TO CLIMB MUCH INTO THE 40S...STILL SOME 10-15 DEGREES BELOW NORMAL. WINDS SHOULD MOSTLY DECOUPLE BY MONDAY NIGHT AS THE SFC RIDGE MOVES OVER THE REGION...BUT SHOULD START TO SEE AN INCREASE IN CIRRUS LATE AS THE CLOSED LOW OVER SRN BAJA THIS AFTERNOON...BEGINS TO NUDGE E INTO NW OLD MX MONDAY NIGHT AND INTO S TX BY WEDNESDAY MORNING. THE INCREASED CIRRUS MAY HELP OFFSET THE MORE IDEAL RADIATIONAL COOLING THAT WOULD NORMALLY TAKE PLACE...BUT STILL EXPECTING MUCH OF THE AREA TO SEE SEVERAL HOURS OF SUBFREEZING TEMPS. THE PROGS HAVE REMAINED FAIRLY CONSISTENT WITH THE TRACK OF THIS LOW THE LAST 24 HOURS...WITH THE ELEVATED MOISTURE INCREASING BY TUESDAY AFTERNOON...WITH AREAS OF -RA DEVELOPING MAINLY OVER E TX/N LA. THE PROGS HAVE BACKED OFF CONSIDERABLY ON QPF WITH THIS SYSTEM AS IT BEGINS TO OPEN UP AND ACCELERATE E ACROSS S LA WEDNESDAY...WITH THE BEST FORCING MAINLY FOCUSED ALONG THE EXTREME SE TX/SRN LA COASTS. HAVE LOWERED POPS TO LOW CHANCE TUESDAY NIGHT AND WEDNESDAY FOR AREAS ALONG/S OF I-20...BEFORE THE NEXT SHORTWAVE CLIPPER ROUNDS THE GREAT LAKES REGION WEDNESDAY AFTERNOON. THIS NEXT SHORTWAVE SHOULD ALLOW FOR ANOTHER COLD FRONT TO NUDGE S WEDNESDAY NIGHT/THURSDAY MORNING...DRIVING TEMPS BACK DOWN TO SOME 10 DEGREES BELOW NORMAL ONCE AGAIN. CAN/T RULE OUT ISOLATED AREAS OF -RA DEVELOPING NEAR/BEHIND THE FROPA...BUT THE MOISTURE PROFILE WILL REMAIN SHALLOW WHILE THE BEST FORCING WILL BE NE OF THE AREA. SHOULD AGAIN BEGIN TO SEE A MODERATION OF TEMPS BY FRIDAY AND ESPECIALLY NEXT WEEKEND...AS TEMPS RETURN BACK ABOVE NORMAL. DRY CONDITIONS SHOULD PERSIST THROUGH NEXT WEEKEND AS WELL. PRELIMS TO FOLLOW BELOW... 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 30 46 26 53 39 / 10 0 0 0 20 MLU 34 44 25 52 35 / 10 0 0 0 20 DEQ 24 42 22 52 32 / 0 0 0 0 0 TXK 28 43 25 52 37 / 10 0 0 0 10 ELD 29 43 23 52 34 / 10 0 0 0 10 TYR 27 43 30 53 40 / 10 0 0 0 20 GGG 28 44 27 53 39 / 10 0 0 0 20 LFK 33 49 29 53 41 / 10 0 0 10 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: LAZ001>006-010>014-021. OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153. && $$ 06
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
547 PM CST SUN FEB 1 2015 .AVIATION... FOR THE 02/00Z TAFS...RAIN HAS MOVED SOUTH AND EAST OF THE TAF SITES AND POST-FRONTAL STRATOCU CONTINUES TO MOVE SEWD AS WELL AND IS GENERALLY SE OF A LINE FROM KLFK TO KMLU. ONCE THE STRATOCU DEPARTS...VFR CONDITIONS WILL PREVAIL. AFTER A BRIEF PERIOD OF CLEARING SKIES...A BAND OF MID LVL CLOUDS WILL MOVE ACROSS THE AREA THIS EVENING/TONIGHT FOLLOWED BY SKC CONDITIONS BY MONDAY AFTERNOON AS A DRY SFC HIGH PRESSURE BUILDS INTO THE REGION. NWLY WINDS WILL REMAIN GUSTY UNTIL DIMINISHING DURING THE DAYTIME HRS MONDAY. /09/ && .PREV DISCUSSION... /ISSUED 359 PM CST SUN FEB 1 2015/ DISCUSSION... THE SCT CONVECTION HAS RAPIDLY MOVED E ACROSS LOWER E TX/NCNTRL LA THIS AFTERNOON ALONG THE COLD FRONT...WHICH EXTENDS FROM THE MS RIVER ALONG THE AR/MS BORDER SW TO LLQ...TO ELD...TO JUST N OF A IER...TO S OF A LFK LINE AS OF 21Z. THE HRRR CONTINUES TO HAVE THE BEST HANDLE ON THE ONGOING CONVECTION...WHICH SHOULD COMPLETELY EXIT THE AREA BY/SHORTLY AFTER 00Z. BEHIND THE FRONT...GUSTY NW WINDS CONTINUE TO EXPAND SE...WITH GUSTS TO 25KTS COMMON ACROSS EXTREME NE TX/SE OK/SW AR. THE SHORT TERM PROGS DO AGREE ON A 6MB PRESSURE DIFFERENCE FROM W TO E ACROSS THE CWA THIS EVENING...AND GIVEN THIS...HAVE EXPANDED THE LAKE WIND ADVISORY THROUGH 10Z MONDAY TO COVER THE REMAINDER OF THE CWA EXCEPT THE LOWER SAM RAYBURN COUNTRY OF DEEP E TX AS WELL AS THE SRN PARISHES OF NCNTRL LA...WHERE WINDS SHOULD BE A BIT MORE MARGINAL. STRONG COLD ADVECTION BEHIND THE FRONT SHOULD RESULT IN FREEZING TEMPS OVER ALL BUT THE SRN AND ERN SECTIONS OF THE REGION...DESPITE THE POST-FRONTAL STRATOCU OVER CNTRL/ERN OK NOT CLEARING UNTIL LATE TONIGHT ACROSS SE OK/SW AR/NCNTRL LA. CANADIAN SFC RIDGING WILL BEGIN TO SETTLE S ACROSS THE SRN PLAINS MONDAY...THUS WEAKENING THE GRADIENT BY DAYBREAK. HOWEVER...EVEN WITH ABUNDANT SUNSHINE...TEMPS WILL STRUGGLE TO CLIMB MUCH INTO THE 40S...STILL SOME 10-15 DEGREES BELOW NORMAL. WINDS SHOULD MOSTLY DECOUPLE BY MONDAY NIGHT AS THE SFC RIDGE MOVES OVER THE REGION...BUT SHOULD START TO SEE AN INCREASE IN CIRRUS LATE AS THE CLOSED LOW OVER SRN BAJA THIS AFTERNOON...BEGINS TO NUDGE E INTO NW OLD MX MONDAY NIGHT AND INTO S TX BY WEDNESDAY MORNING. THE INCREASED CIRRUS MAY HELP OFFSET THE MORE IDEAL RADIATIONAL COOLING THAT WOULD NORMALLY TAKE PLACE...BUT STILL EXPECTING MUCH OF THE AREA TO SEE SEVERAL HOURS OF SUBFREEZING TEMPS. THE PROGS HAVE REMAINED FAIRLY CONSISTENT WITH THE TRACK OF THIS LOW THE LAST 24 HOURS...WITH THE ELEVATED MOISTURE INCREASING BY TUESDAY AFTERNOON...WITH AREAS OF -RA DEVELOPING MAINLY OVER E TX/N LA. THE PROGS HAVE BACKED OFF CONSIDERABLY ON QPF WITH THIS SYSTEM AS IT BEGINS TO OPEN UP AND ACCELERATE E ACROSS S LA WEDNESDAY...WITH THE BEST FORCING MAINLY FOCUSED ALONG THE EXTREME SE TX/SRN LA COASTS. HAVE LOWERED POPS TO LOW CHANCE TUESDAY NIGHT AND WEDNESDAY FOR AREAS ALONG/S OF I-20...BEFORE THE NEXT SHORTWAVE CLIPPER ROUNDS THE GREAT LAKES REGION WEDNESDAY AFTERNOON. THIS NEXT SHORTWAVE SHOULD ALLOW FOR ANOTHER COLD FRONT TO NUDGE S WEDNESDAY NIGHT/THURSDAY MORNING...DRIVING TEMPS BACK DOWN TO SOME 10 DEGREES BELOW NORMAL ONCE AGAIN. CAN/T RULE OUT ISOLATED AREAS OF -RA DEVELOPING NEAR/BEHIND THE FROPA...BUT THE MOISTURE PROFILE WILL REMAIN SHALLOW WHILE THE BEST FORCING WILL BE NE OF THE AREA. SHOULD AGAIN BEGIN TO SEE A MODERATION OF TEMPS BY FRIDAY AND ESPECIALLY NEXT WEEKEND...AS TEMPS RETURN BACK ABOVE NORMAL. DRY CONDITIONS SHOULD PERSIST THROUGH NEXT WEEKEND AS WELL. PRELIMS TO FOLLOW BELOW... 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 30 46 26 53 39 / 10 0 0 0 20 MLU 34 44 25 52 35 / 20 0 0 0 20 DEQ 24 42 22 52 32 / 0 0 0 0 0 TXK 28 43 25 52 37 / 10 0 0 0 10 ELD 29 43 23 52 34 / 10 0 0 0 10 TYR 27 43 30 53 40 / 10 0 0 0 20 GGG 28 44 27 53 39 / 10 0 0 0 20 LFK 33 49 29 53 41 / 10 0 0 10 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: LAZ001>006-010>014-021. OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153. && $$ 09
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
1246 AM EST SAT JAN 31 2015 .SYNOPSIS... HIGH PRESSURE WILL BUILD IN THROUGH SATURDAY. LOW PRESSURE WILL BRING WINTRY WEATHER SUNDAY INTO MONDAY. && .NEAR TERM /THROUGH TODAY/... THE FAA TERMINAL DOPPLER RADAR INDICATES ONLY A COUPLE OF MICROSCALE SNOW BANDS REMAIN...ONE OVER MOSTLY WASHINGTON COUNTY...AND ANOTHER MUCH WEAKER ONE OVER SOUTHWESTERN ALLEGHENY COUNTY. MODEL SOUNDINGS FROM BOTH THE RAP AND HRRR SHOW A SCENARIO WHEREBY INVERSION HEIGHTS ARE FALLING SIMULTANEOUSLY WITH BOUNDARY LAYER MOISTURE DEPTH DECREASING AS WELL. LIKEWISE...UPSTREAM ACTIVITY OFF OF LAKE HURON IS QUICKLY FALLING APART...AND THE TREND TOWARD ANY ADDITIONAL INPUT FROM THE SLIVER OF LAKE ERIE THAT IS OPEN WILL NOT BE PARTICULARLY HELPFUL TO REGENERATION OF ANY OF THE BANDS. THAT SAID...ACTIVITY WILL LIKELY TAKE A FEW HOURS TO WANE WITH THE UPSLOPE AREAS TAKING THE LONGEST TO FULLY HALT THEIR SNOW SHOWER AND FLURRY ACTION. NORTHWESTERLY FLOW CONTINUES THROUGH MUCH OF THE EVENING HOURS BEFORE SLOWLY TURNING WEST OVERNIGHT AS A SURFACE HIGH BUILDS GENERALLY JUST TO THE SOUTH OF THE REGION. WITH AT THE VERY LEAST PARTIAL CLEARING...IF NOT FULL CLEARING AT TIMES...TEMPERATURES SHOULD DROP RAPIDLY WITH NEW SNOW COVER. THIS COMBINED WITH DECREASING YET STILL BRISK SURFACE FLOW WILL ALLOW FOR WIND CHILL ADVISORY CRITERIA WIND CHILL INDEX VALUES BY MORNING OVER THE HIGHER TERRAIN AND NORTHEASTERN CWA. THIS IS IN LINE WITH CURRENT HEADLINES...AND NO ADDITIONAL EXPANSION OF THESE HEADLINES ARE ANTICIPATED AT THIS TIME. HOWEVER...WITH RAPID CLEARING AND NEW SNOW ON THE GROUND...ALL AREAS WILL LIKELY BE VERY COLD BY MORNING...WITH MANY PORTIONS OF THE CWA CHALLENGING OR EVEN DROPPING BELOW ZERO BY THAT JUNCTURE. SOME WARMER AIR DOES START TO FLOW NORTHWARD ON SATURDAY AS THE SURFACE HIGH AXIS MOVES TO THE EAST OF THE AREA AND SOUTHWESTERLY FLOW PREVAILS FOR A TIME. EXPECTATIONS SHOULD BE MUTED...THOUGH...AS SUCH A COLD START AND WEAK VERTICAL MIXING WILL LIKELY KEEP MOST OF THE AREA IN THE 20S. FRIES && .SHORT TERM /TONIGHT THROUGH MONDAY/... HIGH PRES SHOULD CONT DRY WEA INTO SAT EVE. A DIGGING UPR TROF IS PROGGED TO ADVN OUT OF THE PLAINS AND TRACK ACRS THE GT LKS AND OH VLY RGN SUN INTO MON. ASSOCIATED SFC LOW PRES IS PROGGED TO DEEPEN AS IT MOVES ACRS THE TN AND OH VLY RGNS ALSO. THIS WL SPREAD SNW INTO THE RGN LT SAT NGT THRU MON MRNG WITH DEEP AVAILABLE MSTR AND OMEGA. WITH A CLOSED 850MB LOW...A MORE PROLONGED PCPN EVENT IS EXPD AS OPPOSED TO THE OPEN SYSTEM EARLIER IN THE WK. WITH ENOUGH POTENTIAL FOR HEAVY SNW OR A SNW/ICE MIX...ISSUED A WINTER STORM WATCH FOR MUCH OF THE AREA. LEFT AREAS GENLY S OF I 70 OUT OF THE WATCH...EXCEPT FOR THE WV/MD RIDGES...AS ENOUGH WRM AIR IS EXPD TO WRAP IN AHD OF THE LOW TO ALLOW FOR A RAIN/SNW MIX OR EVEN A PD OF ALL RAIN. AREAS BETWEEN I 70- AND I 80 COULD SEE ENOUGH WRM AIR ALOFT FOR FRZG RAIN TO MIX IN AT TIMES AS WELL. GENLY FOLLOWED A SREF/GFS/ECMWF MDL BLEND TO WORK OUT THE DETAILS...AND USED CRITICAL THICKNESSES/MDL SOUNDING PROFILES FOR PCPN TYPE. BEST POTENTIAL FOR GREATER THAN 6 INCHES OF SNW EXISTS N OF PIT BASED ON LATEST MDL GUIDANCE...THOUGH THIS WL BE REFINED OVR THE NXT COUPLE OF DAYS. SNW SHOULD CONT MON UNTIL THE UPR TROF AXIS SHIFTS E IN THE AFTN. NUDGED TEMPS TO THE LATEST COLDER THAN SEASONAL AVG SREF GUIDANCE. && .LONG TERM /MONDAY NIGHT THROUGH FRIDAY/... A COLD...WINTER PATTERN WILL CONTINUE FOR THE REST OF THE LONG TERM. THE NEXT BEST CHANCE FOR SNOW SHOWERS WILL ARRIVE LATE IN THE PERIOD. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... MVFR STRATOCU CONTINUE TO ERODE SLOWLY FROM THE WEST...WITH ONLY A FEW SHSN/FLURRIES REMAINING...AS LAKE HURON CONNECTION GETS CUT OFF WITH WINDS BACKING TO WEST. ONCE THESE BREAK UP...VFR WITH ONLY SCT AC EXPECTED OVERNIGHT THROUGH SUNRISE SATURDAY. SOME BORDERLINE MVFR CIGS SATURDAY AFTERNOON WITH WARM FRONTAL ACTION. VFR THEN EXPECTED TO RETURN FOR THE EVENING...BUT MID/HI CLOUDS WILL BE ON THE INCREASE. HINT AT FIRST -SN AT PIT AROUND 09Z SUNDAY WITH NEXT STORM SYSTEM. CL .OUTLOOK.../SATURDAY NIGHT THROUGH WEDNESDAY/... WIDESPREAD RESTRICTIONS CAN BE EXPECTED SUNDAY AND MONDAY AS A LOW PRESSURE SYSTEM CROSSES THE REGION. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR MDZ001. WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR MDZ001. OH...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR OHZ039>041-048>050-057>059. PA...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR PAZ007>009-013>016-020>023-029-073>076. WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR PAZ008- 009-015-016-023-074-076. WV...WINTER STORM WATCH FROM LATE TONIGHT THROUGH MONDAY MORNING FOR WVZ001>003-023-041. WIND CHILL ADVISORY UNTIL 10 AM EST THIS MORNING FOR WVZ023- 041. && $$
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
912 PM EST SUN FEB 1 2015 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 305 PM EST SUN FEB 1 2015 A MAJOR WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH EARLY MONDAY MORNING BEFORE DEPARTING. BLOWING AND DRIFTING SNOW WILL CONTINUE TO LEAD TO DANGEROUS TRAVEL ESPECIALLY NEAR AND SOUTH OF I-96 AND TOWARD I-94. STORM TOTAL ACCUMULATIONS (INCLUDING WHAT HAS FALLEN ALREADY) BY MONDAY MORNING WILL RANGE FROM A COUPLE INCHES ALONG ROUTE 10 TO AS MUCH AS 12 TO 16 INCHES ALONG I-94. WIND CHILL READINGS WILL FREQUENTLY BE BELOW ZERO FOR MOST MORNINGS THIS WEEK. OCCASIONAL SNOW SHOWERS ARE POSSIBLE THROUGH MID WEEK WITH ADDITIONAL SNOW SHOWERS ONCE AGAIN FOR THE WEEKEND. && .UPDATE... ISSUED AT 908 PM EST SUN FEB 1 2015 NO CHANGES TO THE HEADLINES. THE STORM IS PROGRESSING AS EXPECTED. MODERATE OCCASIONALLY HEAVY SNOW IS FALLING ACROSS THE WARNING AREA AND SEVERAL MORE INCHES OF ACCUMULATION ARE EXPECTED. REGIONAL RADAR SHOWS A MESOSCALE BAND STRETCHING FROM NEAR FLINT TO LANSING TO CHICAGO. HEAVY SNOW IS FALLING WITHIN THAT BAND. WINDS WILL DIMINISH AFTER MIDNIGHT BUT DRIVING WILL REMAIN HAZARDOUS. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 305 PM EST SUN FEB 1 2015 STORM TERM DISCUSSION: LITTLE CHANGE TO OUR EXISTING FORECAST...WITH CONTINUED SNOW AND BLOWING SNOW THROUGH TONIGHT WITH SNOW COVERED ROADS AND DRIFTING SNOW LEADING TO DANGEROUS TRAVEL. RESIDUAL IMPACTS TO THE MONDAY MORNING COMMUTE ARE LIKELY...ESPECIALLY FOR SECONDARY AND RURAL ROADS WHERE UNPLOWED SNOW MAY BE A SIGNIFICANT PROBLEM FOR TRAVEL. THE GFS HAS LED THE WAY WITH THIS SYSTEM AND WILL CONTINUE TO BE FOLLOWED CLOSELY. WV AND IR IMAGERY SHOW THE WESTERN EDGE OF THIS STORM STILL EXTENDS INTO EASTERN NEBRASKA AND WESTERN IOWA...SO STILL A WAYS TO GO YET AS THE DEFORMATION ZONE WORKS INTO THE SOUTHERN CWA TONIGHT. LOOKING AT THE 12Z GFS MULTI- LAYER FN VECTOR CONVERGENCE FROM H925 UP TO H500...THERE ARE INDICATIONS THAT BOTH THE I-94 REGION AND ALSO A SEPARATE AREA FROM SOUTH HAVEN TO GRR WILL BE UNDERNEATH DEEP FORCING...WITH SOME MESOSCALE HEAVY BANDS POSSIBLE WITH ENHANCED SNOWFALL RATES OF 1" OR MORE PER HOUR. THAT SAID...THIS IS A VERY FINE SNOW...AND SETTLING/COMPRESSION UNDOUBTEDLY WILL OCCUR. NEVERTHELESS...AMOUNTS WILL CONTINUE PILING UP THROUGH TONIGHT AS THE WORST OF THE STORM IS EXPECTED TO MANIFEST FROM 21Z THROUGH 06Z. THE DRY SLOT IS EXPECTED TO MOVE AS FAR NORTH AS EXTREME SE MICHIGAN...AND AS SUCH...WEAKLY POSITIVE OR EVEN NEGATIVE EPV ON THE NOSE OF THIS DRY SLOT WILL IMPACT AREAS ALONG/EAST OF AN AZO TO LAN LINE THROUGH 06Z. THIS WILL BE COINCIDENT WITH COMPLETE SATURATION THROUGH THE COLUMN AND ALSO STRONG FGEN WITH THE DEFORMATION ZONE FORECAST TO MOVE INTO THE SOUTHERN/SE CWA BY BOTH THE NAM AND GFS. ALL THIS ADDS CONFIDENCE TO STEADY SNOWFALL RATES OF AROUND OR EVEN A BIT MORE THAN 1"/HOUR TONIGHT NEAR AND SOUTH OF I-96 AND PARTICULARLY NEAR/EAST OF AN AZO TO LAN LINE. BY 00Z OR SHORTLY THEREAFTER...THE DGZ SPLITS INTO TWO REGIONS AS LOW LEVEL TEMPS CONTINUE TO DECLINE...SO A "BONUS" REGION FOR DENDRITIC GROWTH WILL EXIST FOR A SHORT TIME BEFORE THE STORM WINDS DOWN. NOT SURE HOW MUCH THIS WILL ADD TO THE ACCUMS...BUT SOME ENHANCEMENT IS POSSIBLE. AMOUNTS SO FAR NEAR/SOUTH OF I-96 HAVE GENERALLY BEEN 4 TO 8 INCHES. AN ADDITIONAL 4 TO 8 INCHES IS EXPECTED TONIGHT...BRINGING STORM TOTAL ACCUMULATIONS IN THE 8 TO 16 INCH RANGE. THIS IS BASED ON A WEIGHTED BLEND OF ALL AVAILABLE SHORT/LONG RANGE MODELS AS WELL AS WPC GUIDANCE. NORTH OF I-96...WHERE AN ADVISORY IS IN PLACE...STORM TOTAL AMOUNTS WILL TAIL OFF TO AROUND 8 INCHES ACROSS THE VERY SOUTHERN PORTION OF THE ADVISORY AREA TO AS LITTLE AS 2 OR 3 INCHES NEAR ROUTE 10. WINDS...AS ANTICIPATED...HAVE BEEN ON THE UPSWING TODAY. GRR AND MKG HAVE ALREADY GUSTED TO 30 KNOTS OR GREATER. ALTHOUGH HRRR WIND GUSTS ARE TOO HIGH BY 5-10 KNOTS...WILL KEEP THE GENERAL THEME IN MIND WITH OUR GRIDS AND HOLD ONTO GUSTY WINDS THROUGH AT LEAST 06Z. WIND GUSTS TO 40 MPH ARE POSSIBLE BASED ON TRENDS THIS AFTERNOON...MAINLY FROM MKG TO GRR TO LAN...WHERE NE FLOW SEEMS TO BE MAXIMIZED IN THESE TYPES OF SYSTEMS. BLOWING AND DRIFTING SNOW...ESPECIALLY IN RURAL/OPEN AREAS...WILL BE A SIGNIFICANT PROBLEM FOR THE DURATION OF THIS EVENT GIVEN THE DRY NATURE OF THE SNOW AND THE WIND GUSTS. SHORT TERM DISCUSSION: AFTER THE STORM MOVES OUT AROUND 12Z...EXPECTING A MUCH QUIETER MONDAY ASIDE FROM SOME LAKE EFFECT SNOW SHOWERS THAT WILL BLOW INLAND AS WINDS BACK FROM N TO W WITH A RIDGE MOVING INTO THE OHIO VALLEY REGION. ACCUMS ARE ONLY EXPECTED TO BE A FEW TENTHS OF AN INCH. BY TUESDAY NIGHT...A CLIPPER WILL BE MOVING THROUGH THE MIDWEST AND WILL SPREAD SOME LIGHT SNOW INTO SOUTHERN LOWER MICHIGAN. LIGHT ACCUMULATIONS LOOK PROBABLE AT THIS POINT BASED ON MEDIUM RANGE MODEL QPF. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 305 PM EST SUN FEB 1 2015 A FEW LIGHT SNOW SHOWERS AND FLURRIES WILL LINGER WEDNESDAY AS A STRONG UPPER LEVEL PV ANOMALY MOVES ACROSS THE NORTHERN GREAT LAKES REGION AND IN THE WAKE OF THE ARCTIC COLD FRONT. WIDESPREAD SUB ZERO READINGS ARE QUITE POSSIBLE BY EARLY THURSDAY MORNING AS A RESULT OF CLEARING SKIES AND A DRY AIRMASS IN PLACE AS HIGH PRESSURE BUILDS IN IN CONJUNCTION WITH WITH EXTENSIVE SNOW COVER ACROSS MUCH OF OUR FCST AREA BY THEN. HIGH PRESSURE WILL BRING FAIR WEATHER THURSDAY BUT IT WILL BE QUITE COLD WITH MAX TEMPS ONLY REACHING THE TEENS. TEMPS WILL MODERATE FRIDAY AND SATURDAY AS THE UPPER LEVEL PATTERN BECOMES ZONAL. A COLD FRONT DROPPING DOWN FROM THE NW WILL BRING A CHANCE OF LIGHT SNOW FRIDAY NIGHT AND/OR SATURDAY FOLLOWED BY THE ARRIVAL OF ANOTHER COLDER AIRMASS BY SUNDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 721 PM EST SUN FEB 1 2015 MOSTLY LIFR CONDITIONS THROUGH THE EVENING THEN IMPROVEMENT TO IFR AND MVFR LATE TONIGHT AS THE SNOW MOVES OUT. NORTHEAST WINDS WILL GUST OVER 20 KNOTS AND NEAR 30 KNOTS AT TIMES. WINDS WILL DECREASE BUT STILL GUST TO NEAR 20 KNOTS THROUGH MONDAY MORNING SO THE BLOWING SNOW WILL CONTINUE EVEN AFTER THE SNOW ENDS. && .HYDROLOGY... ISSUED AT 300 PM EST SUN FEB 1 2015 ICE FORMATION ON RIVERS IS THE IMMEDIATE HYDRO CONCERN. ARCTIC AIR HAS ARRIVED WITH THE COLDEST TEMPS EXPECTED MONDAY WITH SIMILAR TEMPS FOR THURSDAY AS ANOTHER ARCTIC FRONT MOVES THROUGH. LOWS TONIGHT AND MONDAY MORNING WILL DROP INTO THE SINGLE DIGITS. COLD TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK SO ICE DEVELOPMENT WILL CONTINUE...PLUS THE SNOW THAT FALLS THROUGH MONDAY MORNING WILL ALSO HELP WITH ICE DEVELOPMENT. ICE IS EXPECTED TO REMAIN FAIRLY STABLE AS TEMPS STAY CHILLY. && .CLIMATE... ISSUED AT 153 PM EST SUN FEB 1 2015 FEB 1ST RECORD SNOWFALL FOR GRR IS 6.1" IN 2001. FEB 1ST RECORD SNOWFALL FOR LAN IS 6.2" IN 1967. FEB 1ST RECORD SNOWFALL FOR MKG IS 14.2" IN 1965. WHILE OFFICIAL LONG TERM SNOWFALL RECORDS ARE NOT MAINTAINED OUTSIDE OF THESE LOCAL CLIMATOLOGICAL DATA (LCD) STATIONS...SNOWFALL AMOUNTS OF 10" OR MORE IN A SINGLE CALENDAR DAY WILL LIKELY RANK IN THE TOP 10 OR TOP 5 FOR THE ENTIRE MONTH OF FEBRUARY FOR MANY LOCATIONS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING UNTIL 6 AM EST MONDAY FOR MIZ056>059- 064>067-071>074. WINTER WEATHER ADVISORY UNTIL 6 AM EST MONDAY FOR MIZ037>040- 043>046-050>052. LM...NONE. && $$ UPDATE...04 SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...LAURENS AVIATION...OSTUNO HYDROLOGY...EBW/HOVING CLIMATE...HOVING
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
721 PM EST SUN FEB 1 2015 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 305 PM EST SUN FEB 1 2015 A MAJOR WINTER STORM WILL CONTINUE TO IMPACT THE REGION THROUGH EARLY MONDAY MORNING BEFORE DEPARTING. BLOWING AND DRIFTING SNOW WILL CONTINUE TO LEAD TO DANGEROUS TRAVEL ESPECIALLY NEAR AND SOUTH OF I-96 AND TOWARD I-94. STORM TOTAL ACCUMULATIONS (INCLUDING WHAT HAS FALLEN ALREADY) BY MONDAY MORNING WILL RANGE FROM A COUPLE INCHES ALONG ROUTE 10 TO AS MUCH AS 12 TO 16 INCHES ALONG I-94. WIND CHILL READINGS WILL FREQUENTLY BE BELOW ZERO FOR MOST MORNINGS THIS WEEK. OCCASIONAL SNOW SHOWERS ARE POSSIBLE THROUGH MID WEEK WITH ADDITIONAL SNOW SHOWERS ONCE AGAIN FOR THE WEEKEND. && .SHORT TERM...(THIS EVENING THROUGH TUESDAY NIGHT) ISSUED AT 305 PM EST SUN FEB 1 2015 STORM TERM DISCUSSION: LITTLE CHANGE TO OUR EXISTING FORECAST...WITH CONTINUED SNOW AND BLOWING SNOW THROUGH TONIGHT WITH SNOW COVERED ROADS AND DRIFTING SNOW LEADING TO DANGEROUS TRAVEL. RESIDUAL IMPACTS TO THE MONDAY MORNING COMMUTE ARE LIKELY...ESPECIALLY FOR SECONDARY AND RURAL ROADS WHERE UNPLOWED SNOW MAY BE A SIGNIFICANT PROBLEM FOR TRAVEL. THE GFS HAS LED THE WAY WITH THIS SYSTEM AND WILL CONTINUE TO BE FOLLOWED CLOSELY. WV AND IR IMAGERY SHOW THE WESTERN EDGE OF THIS STORM STILL EXTENDS INTO EASTERN NEBRASKA AND WESTERN IOWA...SO STILL A WAYS TO GO YET AS THE DEFORMATION ZONE WORKS INTO THE SOUTHERN CWA TONIGHT. LOOKING AT THE 12Z GFS MULTI- LAYER FN VECTOR CONVERGENCE FROM H925 UP TO H500...THERE ARE INDICATIONS THAT BOTH THE I-94 REGION AND ALSO A SEPARATE AREA FROM SOUTH HAVEN TO GRR WILL BE UNDERNEATH DEEP FORCING...WITH SOME MESOSCALE HEAVY BANDS POSSIBLE WITH ENHANCED SNOWFALL RATES OF 1" OR MORE PER HOUR. THAT SAID...THIS IS A VERY FINE SNOW...AND SETTLING/COMPRESSION UNDOUBTEDLY WILL OCCUR. NEVERTHELESS...AMOUNTS WILL CONTINUE PILING UP THROUGH TONIGHT AS THE WORST OF THE STORM IS EXPECTED TO MANIFEST FROM 21Z THROUGH 06Z. THE DRY SLOT IS EXPECTED TO MOVE AS FAR NORTH AS EXTREME SE MICHIGAN...AND AS SUCH...WEAKLY POSITIVE OR EVEN NEGATIVE EPV ON THE NOSE OF THIS DRY SLOT WILL IMPACT AREAS ALONG/EAST OF AN AZO TO LAN LINE THROUGH 06Z. THIS WILL BE COINCIDENT WITH COMPLETE SATURATION THROUGH THE COLUMN AND ALSO STRONG FGEN WITH THE DEFORMATION ZONE FORECAST TO MOVE INTO THE SOUTHERN/SE CWA BY BOTH THE NAM AND GFS. ALL THIS ADDS CONFIDENCE TO STEADY SNOWFALL RATES OF AROUND OR EVEN A BIT MORE THAN 1"/HOUR TONIGHT NEAR AND SOUTH OF I-96 AND PARTICULARLY NEAR/EAST OF AN AZO TO LAN LINE. BY 00Z OR SHORTLY THEREAFTER...THE DGZ SPLITS INTO TWO REGIONS AS LOW LEVEL TEMPS CONTINUE TO DECLINE...SO A "BONUS" REGION FOR DENDRITIC GROWTH WILL EXIST FOR A SHORT TIME BEFORE THE STORM WINDS DOWN. NOT SURE HOW MUCH THIS WILL ADD TO THE ACCUMS...BUT SOME ENHANCEMENT IS POSSIBLE. AMOUNTS SO FAR NEAR/SOUTH OF I-96 HAVE GENERALLY BEEN 4 TO 8 INCHES. AN ADDITIONAL 4 TO 8 INCHES IS EXPECTED TONIGHT...BRINGING STORM TOTAL ACCUMULATIONS IN THE 8 TO 16 INCH RANGE. THIS IS BASED ON A WEIGHTED BLEND OF ALL AVAILABLE SHORT/LONG RANGE MODELS AS WELL AS WPC GUIDANCE. NORTH OF I-96...WHERE AN ADVISORY IS IN PLACE...STORM TOTAL AMOUNTS WILL TAIL OFF TO AROUND 8 INCHES ACROSS THE VERY SOUTHERN PORTION OF THE ADVISORY AREA TO AS LITTLE AS 2 OR 3 INCHES NEAR ROUTE 10. WINDS...AS ANTICIPATED...HAVE BEEN ON THE UPSWING TODAY. GRR AND MKG HAVE ALREADY GUSTED TO 30 KNOTS OR GREATER. ALTHOUGH HRRR WIND GUSTS ARE TOO HIGH BY 5-10 KNOTS...WILL KEEP THE GENERAL THEME IN MIND WITH OUR GRIDS AND HOLD ONTO GUSTY WINDS THROUGH AT LEAST 06Z. WIND GUSTS TO 40 MPH ARE POSSIBLE BASED ON TRENDS THIS AFTERNOON...MAINLY FROM MKG TO GRR TO LAN...WHERE NE FLOW SEEMS TO BE MAXIMIZED IN THESE TYPES OF SYSTEMS. BLOWING AND DRIFTING SNOW...ESPECIALLY IN RURAL/OPEN AREAS...WILL BE A SIGNIFICANT PROBLEM FOR THE DURATION OF THIS EVENT GIVEN THE DRY NATURE OF THE SNOW AND THE WIND GUSTS. SHORT TERM DISCUSSION: AFTER THE STORM MOVES OUT AROUND 12Z...EXPECTING A MUCH QUIETER MONDAY ASIDE FROM SOME LAKE EFFECT SNOW SHOWERS THAT WILL BLOW INLAND AS WINDS BACK FROM N TO W WITH A RIDGE MOVING INTO THE OHIO VALLEY REGION. ACCUMS ARE ONLY EXPECTED TO BE A FEW TENTHS OF AN INCH. BY TUESDAY NIGHT...A CLIPPER WILL BE MOVING THROUGH THE MIDWEST AND WILL SPREAD SOME LIGHT SNOW INTO SOUTHERN LOWER MICHIGAN. LIGHT ACCUMULATIONS LOOK PROBABLE AT THIS POINT BASED ON MEDIUM RANGE MODEL QPF. .LONG TERM...(WEDNESDAY THROUGH SUNDAY) ISSUED AT 305 PM EST SUN FEB 1 2015 A FEW LIGHT SNOW SHOWERS AND FLURRIES WILL LINGER WEDNESDAY AS A STRONG UPPER LEVEL PV ANOMALY MOVES ACROSS THE NORTHERN GREAT LAKES REGION AND IN THE WAKE OF THE ARCTIC COLD FRONT. WIDESPREAD SUB ZERO READINGS ARE QUITE POSSIBLE BY EARLY THURSDAY MORNING AS A RESULT OF CLEARING SKIES AND A DRY AIRMASS IN PLACE AS HIGH PRESSURE BUILDS IN IN CONJUNCTION WITH WITH EXTENSIVE SNOW COVER ACROSS MUCH OF OUR FCST AREA BY THEN. HIGH PRESSURE WILL BRING FAIR WEATHER THURSDAY BUT IT WILL BE QUITE COLD WITH MAX TEMPS ONLY REACHING THE TEENS. TEMPS WILL MODERATE FRIDAY AND SATURDAY AS THE UPPER LEVEL PATTERN BECOMES ZONAL. A COLD FRONT DROPPING DOWN FROM THE NW WILL BRING A CHANCE OF LIGHT SNOW FRIDAY NIGHT AND/OR SATURDAY FOLLOWED BY THE ARRIVAL OF ANOTHER COLDER AIRMASS BY SUNDAY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 721 PM EST SUN FEB 1 2015 MOSTLY LIFR CONDITIONS THROUGH THE EVENING THEN IMPROVEMENT TO IFR AND MVFR LATE TONIGHT AS THE SNOW MOVES OUT. NORTHEAST WINDS WILL GUST OVER 20 KNOTS AND NEAR 30 KNOTS AT TIMES. WINDS WILL DECREASE BUT STILL GUST TO NEAR 20 KNOTS THROUGH MONDAY MORNING SO THE BLOWING SNOW WILL CONTINUE EVEN AFTER THE SNOW ENDS. && .HYDROLOGY... ISSUED AT 300 PM EST SUN FEB 1 2015 ICE FORMATION ON RIVERS IS THE IMMEDIATE HYDRO CONCERN. ARCTIC AIR HAS ARRIVED WITH THE COLDEST TEMPS EXPECTED MONDAY WITH SIMILAR TEMPS FOR THURSDAY AS ANOTHER ARCTIC FRONT MOVES THROUGH. LOWS TONIGHT AND MONDAY MORNING WILL DROP INTO THE SINGLE DIGITS. COLD TEMPERATURES ARE EXPECTED THROUGH THE REST OF THE WEEK SO ICE DEVELOPMENT WILL CONTINUE...PLUS THE SNOW THAT FALLS THROUGH MONDAY MORNING WILL ALSO HELP WITH ICE DEVELOPMENT. ICE IS EXPECTED TO REMAIN FAIRLY STABLE AS TEMPS STAY CHILLY. && .CLIMATE... ISSUED AT 153 PM EST SUN FEB 1 2015 FEB 1ST RECORD SNOWFALL FOR GRR IS 6.1" IN 2001. FEB 1ST RECORD SNOWFALL FOR LAN IS 6.2" IN 1967. FEB 1ST RECORD SNOWFALL FOR MKG IS 14.2" IN 1965. WHILE OFFICIAL LONG TERM SNOWFALL RECORDS ARE NOT MAINTAINED OUTSIDE OF THESE LOCAL CLIMATOLOGICAL DATA (LCD) STATIONS...SNOWFALL AMOUNTS OF 10" OR MORE IN A SINGLE CALENDAR DAY WILL LIKELY RANK IN THE TOP 10 OR TOP 5 FOR THE ENTIRE MONTH OF FEBRUARY FOR MANY LOCATIONS. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...WINTER STORM WARNING UNTIL 6 AM EST MONDAY FOR MIZ056>059- 064>067-071>074. WINTER WEATHER ADVISORY UNTIL 6 AM EST MONDAY FOR MIZ037>040- 043>046-050>052. LM...NONE. && $$ SYNOPSIS...HOVING SHORT TERM...HOVING LONG TERM...LAURENS AVIATION...OSTUNO HYDROLOGY...EBW/HOVING CLIMATE...HOVING
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
613 PM EST SUN FEB 1 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EST SUN FEB 1 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. TO THE SOUTH...A VIGOROUS SHRTWV TROUGH INTO NRN IL WAS BRINGING HEAVY SNOW FROM IA INTO THE SRN LAKES. AT THE SFC...DRY NE FLOW PREVAILED THROUGH LAKE SUPERIOR AND UPPER MI BETWEEN A 1036 MB HIGH OVER ERN NORTH DAKOTA AND A 1003 MB LOW OVER ERN IL. 900 MB TEMPS AROUND -22C PROVIDED ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...INVERSION HEIGHTS AROUND 3K FT AND A DGZ BELOW 1K FT HAS LIMITED INTENSITY AND ACCUMULATION POTENTIAL. TONIGHT...EXPECT THE WINDS TO GRADUALLY BACK TO NRLY AS THE IL LOW MOVES TO THE E AND THE HIGH BUILDS INTO THE CNTRL PLAINS. WITH A RELATIVELY LIGHT WIND FIELD...LAND BREEZE EFFECTS AND THE DEVELOPMENT OF LOCALIZED CIRCULATIONS OR AREAS OF CONVERGENCE WILL BE MORE LIKELY. THE HIGHER RES MODELS SUGGEST THAT A BAND MAY DEVELOP THAT WOULD AFFECT FAR ERN OR WRN ALGER COUNTY TONIGHT. INVERSION HEIGHTS REMAINING AROUND 3K FT SHOULD LIMIT ACCUMULATION POTENTIAL TO A FEW INCHES. THERE MAY ALSO BE A SHORELINE PARALLEL BAND NEAR THE WEST BUT CONFIDENCE IN WHERE IT MAY AFFECT THE SHORELINE IS LOW. BESIDES THE LES...TEMPS WILL FALL BELOW ZERO TONIGHT...ESPECIALLY OVER THE FAR ERN COUNTIES AND ALONG THE WI BORDER OF THE INTERIOR WEST. FORTUNATELY...WITH THE LIGHT WINDS AND SOME LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS SHOULD REMAIN IN THE -10 TO -20 RANGE...NOT REACHING ADVY CRITERIA. MON...SOME LINGERING LES IN THE N TO NW SNOWBELTS AS 900 MB TEMPS WILL BE AROUND -22C WILL BE PUSHED OFFSHORE AS A TROUGH DEVELOPS OVER NRN MN INTO NRN LAKE SUPERIOR AND THE HIGH PRES SHIFTS TO THE OH VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 350 PM EST SUN FEB 1 2015 COLD CONDITIONS WITH BELOW NORMAL TEMPS EXPECTED THIS WEEK AS RIDGING FROM EASTERN RUSSIA AND THE BERING SEA TO THE WESTERN CONUS ALLOWS TROUGHING TO EXPAND ACROSS THE GREAT LAKES FM EASTERN CANADA. RIDGING BEGINS TO FLATTEN BY END OF THE EXTENDED PERIOD SUGGESTING THAT TEMPS WILL BOUNCE BACK TOWARD NORMAL OR MAYBE ABOVE BEYOND NEXT WEEKEND. DAYTIME HIGHS FOR A COUPLE DAYS WILL STAY IN THE SINGLE DIGITS BUT OTHERWISE WILL BE IN THE TEENS. NIGHTTIME LOWS WILL MAINLY BE IN THE SINGLE DIGITS BLO ZERO TO THE SINGLE DIGITS ABOVE. MAY HAVE TO DEAL WITH WIND CHILL ISSUES...ESPECIALLY ON THURSDAY MORNING. COLDEST DAYS LIKELY WEDNESDAY AND THURSDAY AS CORE OF ARCTIC AIR WITH H85 TEMPS BLO -25C SWEEPS OVER THE UPPER GREAT LAKES. WIDESPREAD SNOW CHANCES STILL ON THE LOWER SIDE IN THIS PATTERN. FOR LAST COUPLE DAYS...PRIMARY EXTENDED MODELS OF ECMWF/GFS AND GEM-NH ALONG WITH GFS ENSEMBLES HAVE HINTED AT BETTER SHOT OF SNOW OVER MUCH OF THE UPPER LAKES REGION FRIDAY AFTERNOON INTO SATURDAY AS A COLD FRONT SLIDES ACROSS THE AREA. DETAILS STILL NEED TO BE SORTED OUT THOUGH AS MODEL CONSISTENCY IS LACKING. AT THE BEGINNING OF THE LONG TERM...HIGH PRESSURE CENTER SETTLES TO THE LOWER MISSISSIPP RIVER VALLEY ON MONDAY EVENING. A TROUGH WILL BE APPROACHING LK SUPERIOR FM NORTHERN ONTARIO. WEAK SHORTWAVE/PV ANAMOLY SLIDES THROUGH AND SOUNDINGS EVEN INLAND SHOW MARGINAL DEEP MOISTENING H8-H5 WITH WEAK LIFT. LGT SNOW OR FLURRIES MOST AREAS LATER MONDAY EVENING INTO THE OVERNIGHT. BIGGER IMPACT MAY OCCUR OVER NORTHERN KEWEENAW PENINSULA AS BAND OF MODERATE TO POSSIBLY HEAVY LES COULD BE ONGOING. LIFT FM THE DISTURBANCE ALONG WITH H85 TEMPS NEAR -20C YIELDS 1000-850MB LAPSE RATES OVER 9C/KM WHERE STRONGER CONVERGENCE COMES TOGETHER. LOCAL HIRES WRF MODEL SEEMS REASONABLE SHOWING OVER 0.05 INCH OF QPF PER HOUR IN HEAVIER BANDING. SO WITH SLR/S OVER 20:1...COULD BE OVER 1 INCH OF SNOW PER HOUR...WHICH FITS THIS TYPE OF LES REGIME. DOES APPEAR THAT WITH ARRIVAL OF TROUGH THE HEAVIEST SNOW WILL NOT LAST PROBABLY MORE THAN A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL. OVERALL...SEEMS LIKE MODELS/PATTERN RECOGNITION POINTS TO ADVY FOR TIP OF KEWEENAW MONDAY EVENING...BEFORE THE LES SINKS ACROSS REST OF KEWEENAW AND BECOMES MORE MULTIBAND IN TYPE. CONTINUE TO MENTION IN HWO. ONCE THE SFC TROUGH MOVES THROUGH LATE MONDAY NIGHT INTO TUESDAY MORNING AND LARGER SCALE FORCING EVADES...EXPECT NW FLOW LES THROUGH TUESDAY NIGHT. LOW INVERSIONS BLO 4KFT AND NEUTRAL TO ANTICYLONIC FLOW WILL LIMIT INTENSITY OF LES DESPITE ALL OF THE CLOUD BEING WITHIN THE DGZ. FLUFFY ACCUMS EXPECTED BUT LOW IMPACT AS WINDS WILL BE LIGHT. AS THIS OCCURS...LOW PRESSURE SYSTEM MOVES OVER THE NORTHERN PLAINS AND EVENTUALLY SPREADS LGT SNOW OVER THE WESTERN GREAT LAKES REGION ON TUESDAY NIGHT. NAM FARTHER NORTH WITH THE QPF COMPARED TO THE MORE CONSISTENT ECWMF/GFS AND GEM-NH. WILL SHOOT FOR A MAINLY DRY FORECAST AWAY FM THE LK SUPERIOR LES. PRIMARY HAZARDOUS WEATHER POTENTIAL WILL BE TIED TO LAKE EFFECT AND BLSN/DRSN THAT RAMPS UP WEDNESDAY AND WEDNESDAY NIGHT FOR AREAS NEAR LK SUPERIOR FAVORED BY NORTHWEST WINDS. THIS IS IN WAKE OF THE LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT THAT CROSS THE AREA ON TUESDAY NIGHT. INVERSION HEIGHTS RISING TO AT LEAST 8KFT AND LAKE EQL OVER 10KFT POINT TO MODERATE TO HEAVY SNOW. DUE TO DEPTH OF COLD THOUGH...SOUNDINGS INDICATE MOST OF THE LAKE EFFECT CONVECTIVE LAYER WILL BE AT TEMPS BLO -20C. SO...LOOKING AT SMALL SNOW FLAKES GOOD AT REDUCING VSBY...BUT NOT PILING UP A LOT OF SNOW. WINDS IN THE MIXED LAYER 25-30 KTS...SO BLSN/DRSN WILL BE PREVALENT WITH THE FINE SNOW FLAKES. EXPECT THERE WILL NEED TO BE SOME WINTER WEATHER HEADLINES CENTERED ON WEDNESDAY INTO WEDNESDAY NIGHT. AWAY FM THE LES AND BLSN/DRSN...APPEARS CONDITIONS OVER AT LEAST INTERIOR WEST WILL BE CLOSE TO WIND CHILL ADVISORY CRITERIA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. EXPECT READINGS 20 TO 25 BLO ZERO WHICH IS CLOSE TO...BUT NOT QUITE REACHING CRITERIA OF 25 TO 35 BLO. WILL CONTINUE TO MENTION THIS IN THE HWO...BUT IS NOT APPEARING TO BE AN OVERWHELMING LOW WIND CHILL EVENT. ANOTHER TROUGH...REALLY MORE OF A WARM FRONT ALOFT...SLIDES OVER NORTHERN ONTARIO AND LK SUPERIOR THURSDAY AFTN THROUGH THURSDAY NIGHT. WINDS BACKING SW AHEAD OF THE TROUGH IN LOW-LEVELS WILL PUSH LES OVER LK SUPERIOR AND WINDS APPEAR TO HAVE TOO MUCH WESTERLY COMPONENT TO RESULT IN LES OFF LK MICHIGAN FM KISQ TO KERY. MID- LEVEL MOISTURE WITH WEAK LIFT MAY SQUEEZE OUT LGT SNOW OR FLURRIES FOR MOST OF THE CWA. CONSISTENCY NOT THERE YET FOR FRIDAY AND SATURDAY SO WILL RUN WITH FORECAST CONSENSUS ATTM. BEST CHANCES OF A WIDESPREAD SNOW PROBABLY FRIDAY NIGHT WITH INCREASING UNCERTAINTY FOR THAT ON SATURDAY. FRONT WILL BE IN THE VCNTY AND LATEST INDICATIONS FM MODELS AND HAND DRAWN PROG FM WPC SHOWS IT MAINLY SOUTH OF AREA ON SUNDAY WITH LOW CHANCES FOR LES IN AN EASTERLY FLOW. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 613 PM EST SUN FEB 1 2015 MVFR CONDITIONS WITH OCNL IFR VSBY IN LAKE CLOUDS AND LIGHT SNOW SHOWERS WILL CONTINUE AT SAW AND CMX THIS EVENING IN A NE-N FLOW. IWD WILL SEE MVFR CONDITIONS TONIGHT IN THE SNOW SHOWERS. IWD AND SAW WILL BACK WINDS TO THE SOUTHWEST AND PUSH THE LAKE EFFECT CLOUDS NORTH OF THE AREA AND SHOULD GO VFR MON MORNING WHILE CMX STAYS IN THE LAKE EFFECT MVFR CATEGORY CLOUDS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 350 PM EST SUN FEB 1 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH ON MONDAY...THEN TURN TO THE NORTHWEST BEHIND THE TROUGH ON TUESDAY. WINDS THROUGH TUESDAY AT OR BLO 30 KTS. HEAVY FREEZING SPRAY OVER PORTIONS OF LK SUPERIOR ON MONDAY NIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES IN GUSTS WEDNESDAY AND WEDNESDAY EVENING. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
344 PM EST SAT JAN 31 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 340 PM EST SAT JAN 31 2015 THIS AFTERNOON THROUGH SUNDAY...HIGH PRESSURE SLIDING ACROSS CENTRAL CANADA THIS AFTERNOON HAS ALLOW NORTHERLY FLOW TO INCREASE ACROSS MUCH OF THE UPPER GREAT LAKES REGION. THIS NORTHERLY FLOW COUPLED WITH 850MB TEMPERATURES COOLING TO AROUND -18C TO -20C HAS ALLOWED LAKE EFFECT SNOW TO DEVELOP AHEAD OF THE SURFACE HIGH PRESSURE SYSTEM. INITIALLY...DEEPER MOISTURE WILL LINGER INTO THE EARLY EVENING HOURS ALLOWING BETTER SNOW GROWTH WITH A THICKER SNOW GROTH AREA WITHIN THE DGZ. RUC SOUNDINGS SHOW INVERSION HEIGHTS BETWEEN 4KFT AND 5KFT THIS AFETERNOON WHICH IS ALSO VERIFIED BY THE MQT VAD WIND PROFILE THIS AFETERNOON. THIS HAS ALLOWED GOOD SNOWFLAKE SIZE THIS AFTERNOON RESULTING IN A QUICK INCH OR TWO OF FLUFFY SNOW ON A NORTH TO NORTHWESTERLY WIND. DRY AIR REMAINS JUST TO THE NORTH OF THE AREA THIS AFTERNOON...HOWEVER...THIS IS EXPECTED TO SHIFT FARTHER SOUTH AROUND 00Z/01 AS INVERSION HEIGHTS BEGIN TO FALL TO AROUND 3KFT. THIS SHOULD HELP TO REDUCE SNOWFALL RATES THIS EVENING INTO THE OVERNIGHT HOURS. AS THE SURFACE RIDGE EXPANDS TO THE NORTH OF LAKE SUPERIOR EXPECT WINDS TO SHIFT TO THE NORTH AND NORTHEAST SHIFTING THE SNOWBANDS TO THE NORTH TO NORTHEAST WIND FAVORED SNOW BELTS. AGAIN...REDUCED MOISTURE...LOWERED INVERSION HEIGHTS ALONG WITH ANTICYCLONIC FLOW WILL HELP TO KEEP SNOWFALL TOTALS IN CHECK ACROSS THE U.P. WITH UP TO 2 INCHES EXPECTED ALONG THE NORTH TO NORTHEAST WIND FAVORED SNOW BELTS. AS THE SURFACE RIDGE CENTER SHIFTS INTO THE NORTHERN PLAINS ON SUNDAY EXPECT WINDS TO SHIFT TO A MORE NORTHERLY DIRECTION. TEMPERATURES ALOFT WILL REMAIN COLD ENOUGH AND LOW LEVEL MOISTURE OFF LAKE SUPERIOR WILL KEEP LAKE EFFECT SNOW IN NORTHERLY WIND FAVORED LOCATIONS...WITH AROUND AN INCH ACCUMULATION EXPECTED IN THESE AREAS. .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 340 PM EST SAT JAN 31 2015 ...NW FLOW LES AND POOR VSBY DUE TO BLSN/DRSN MAY LEAD TO HEADLINES WEDNESDAY INTO THURSDAY... COLD WEEK IN STORE AS A BUILDING RIDGE ALOFT OVER WESTERN NORTH AMERICA RESULTS IN MEAN TROUGHING CENTERED OVER HUDSON BAY EXTENDING OVER GREAT LAKES AND NORTHEAST CONUS. PATTERN DOES NOT HOLD MUCH OPPORTUNITY FOR WIDESPREAD SNOW. BEST CHANCE OF THAT MAY ACTUALLY COME FRIDAY. OTHERWISE...LAKE EFFECT SNOW AND BLOWING/DRIFTING SNOW WITH POOR VISIBILITY WILL BE MAIN ISSUE. APPEARED THAT MODERATION IN THE CHILL WOULD START TO DEVELOP BY NEXT WEEKEND...BUT RECENT RUNS OF THE ECMWF/GFS HAVE TRENDED TOWARD MORE TROUGHING AND COLDER TEMPERATURES. WILL HAVE TO WAIT AND SEE IF THIS IS A LASTING TREND. HIGH IMPACT WEATHER THAT JUSTIFIES ANY TYPE OF HEADLINES THROUGH THE EXTENDED LIKELY WILL BE TIED TO THE LAKE EFFECT SNOW AND POOR VSBY. BEST CHANCE OF SEEING HEADLINES WILL BE WEDNESDAY INTO THURSDAY FOR NW FLOW AREAS NEAR LK SUPERIOR. WILL ALSO GIVE AN HONORABLE MENTION FOR WSW FLOW ON TIP OF KEWEENAW PENINSULA LATE MONDAY INTO MONDAY NIGHT...AS THOUGH THIS IS A VERY LOW PROBABILITY EVENT IT COULD NEED A HEADLINE IF IT OCCURS. SUPPOSE THERE ALSO COULD BE NEED FOR WIND CHILL ADVYS MONDAY MORNING AND AGAIN THURSDAY MORNING...BUT ATTM IT DOES NOT LOOK LIKE A SURE THING THANKS TO LIGHT WINDS AND/OR MORE IN TERMS OF LAKE MODERATION ON TEMPS. NO REAL HAZARDOUS WEATHER EXPECTED SUNDAY NIGHT INTO MONDAY MORNING WITH DIMINISHING WINDS AND WEAK LES AS INVERSIONS ARE WELL BLO 5KFT. PLENTY COLD WITH TEMPS AT INVERION TOP BLO -20C. SLR/S ON THE HIGHER/FLUFFY SIDE SO A COUPLE OF INCHES OF SNOW IS POSSIBLE FOR MAINLY NCNTRL UPR MICHIGAN. GIVEN THE WEAKENING WINDS...MESOLOW FORMATION REMAINS POSSIBLE WHICH WOULD ENHANCE CONVERGENCE AND ADD TO THE SNOW AMOUNTS. HIGHEST PROBABILITY OF THIS OCCURRING WOULD BE BTWN MARQUETTE AND PICTURED ROCKS LAKESHORE...SO LOOKING AT AU TRAIN AND MUNISING AREAS. AWAY FM THE LES...TEMPS FALL WELL BLO ZERO LATE SUNDAY NIGHT INTO MONDAY MORNING...BUT WITH LIGHT WINDS AND SOME LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS WILL MAINLY STAY HIGHER THAN 20 BLO. SFC TROUGH CROSSING THE AREA MONDAY MORNING SHOULD RESULT IN WINDS BECOMING MORE WESTERLY WHICH WILL DISRUPT THE LES OVER ALGER COUNTY BUT WILL INCREASE IT ON THE KEWEENAW PENINSULA. WESTERLY CONVERGENT FLOW LES HAS POTENTIAL TO DROP SEVERAL INCHES OF SNOW LATE MONDAY AFTN INTO MONDAY NIGHT OVER NORTHERN SECTIONS OF THE KEWEENAW. SOUNDINGS SHOW INVERSION AT LEAST TO 5KFT AND DISTURBANCE ROTATING THROUGH AHEAD OF ANOTHER TROUGH MOVING OVER UPPER GREAT LAKES ON TUESDAY MORNING. NAM SHARPER WITH TROUGH AND BACKS WINDS ENOUGH TO KEEP HEAVIER LES OFFSHORE OF KEWEENAW. GFS AND ECMWF NOT AS BACKED WITH WINDS. WILL CONTINUE TO SHOW HIGHEST POPS ON THE KEWEENAW AND MENTION IN HAZARDOUS WEATHER OUTLOOK. TROUGH SINKS OVER NORTHERN UPR MICHIGAN THROUGH DAY ON TUESDAY... SPREADING THE LES TO NW FLOW SNOW BELTS OF NORTHERN UPR MICHGAN... ESPECIALLY BY TUESDAY NIGHT. SOUNDINGS SHOW INVERSIONS UP TO 6-8 KFT IN WAKE OF THE TROUGH WITH AS H85 TEMPS DROP TO -25C BY DAYBREAK ON WEDNESDAY. SETUP WILL THEN FAVOR A PUSH OF HEAVIER LES AS THE MAIN COLD FRONT MOVES THROUGH TUESDAY NIGHT INTO WEDNESDAY MORNING WITH CONDITIONS QUICKLY TRANSITIONING TO SMALL SNOWFLAKE/LOW VSBY LES REGIME FOR THE NORTHWEST WIND SNOW BELTS WEDNESDAY AFTN INTO WEDNESDAY NIGHT. BLYR WINDS INCREASE THROUGH WEDNESDAY TO 25-30 KTS SO BLSN AND DRSN WILL ALSO BECOME A CONCERN IN OPEN AREAS NEAR LK SUPERIOR AND ESPECIALLY WHERE ICE IS BUILT UP ALONG THE SHORELINE. AWAY FM THE LES THE MAIN THEME WILL BE COLD. TEMPS ON WEDNESDAY WILL ONLY STRUGGLE INTO THE SINGLE DIGITS ABOVE ZERO WITH WIND CHILL READINGS 10 TO 20 BLO ZERO. AS TEMPS FALL OFF WELL BLO ZERO ON WEDNESDAY NIGHT OVER WESTERN UPR MICHIGAN...MAY SEE WIND CHILL READINGS MAY COME CLOSE TO ADVY INTO THURSDAY MORNING. WINDS WILL BE SLACKENING BY THIS TIME THOUGH...ESPECIALLY OVER INTERIOR SECTIONS OF CWA. A BIT OF MODERATION ON THURSDAY FOR HIGHS WITH READINGS NEARING 10 DEGREES OR REACHING THE LOWER TEENS. BLYR WINDS BACK SW LATER THURSDAY INTO THURSDAY NIGHT AS HIGH PRESSURE RIDGE SETTLES FM THE MIDDLE MISSISSIPPI RIVER VALLEY TO THE OHIO VALLEY. EXPECT THE LES TO SHIFT OFFSHORE BY THURSDAY NIGHT. SINCE UPPER LAKES WILL BE AHEAD OF ANOTHER SFC TROUGH CROSSING SOUTH CENTRAL CANADA...EXPECT CLOUDS TO BE ON THE INCREASE WITH EVEN A POSSIBILITY OF LGT SNOW OR FLURRIES. THUS...TEMPS SHOULD NOT CRASH TOO MUCH ON THURSDAY NIGHT. STRONGER COLD FRONT WITH ANOTHER PUSH OF COLDER AIR EXPECTED TO ARRIVE FRIDAY NIGHT INTO SATURDAY. SHORTWAVE/CONVERGENCE ALONG THE SFC-H85 FRONT AND UPPER DIVERGENCE ON NOSE OF H3 JET STREAK COMBINE TO SPREAD SWATH OF SNOW OVER MOST OF UPR MICHIGAN FRIDAY AFTN INTO FRIDAY EVENING. TIMING MAY SHIFT AROUND SOME THOUGH CONSIDERING THIS SOLUTION IN THE MODELS IS NEWER DEVELOPMENT. LOW CHANCE POPS WILL WORK FOR NOW WITH THE SNOW ALONG THE COLD FRONT AND THEN MORE LOW CHANCE POPS FOR NEXT SATURDAY WITH DEVELOPING NE FLOW LES IN WAKE OF THE FRONT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1226 PM EST SAT JAN 31 2015 AS THE COLD FRONT CONTINUES TO SAG TO THE SOUTH OF THE REGION THIS AFTERNOON...WINDS HAVE TURNED TO THE NORTH TO NORTHWEST. CLOUD COVER IS EXPECTED TO LINGER THROUGH THE TAF PERIOD AT EACH SITE...HOWEVER...THE FOCUS OF THE LOW CLOUD COVER WILL SHIFT FROM THE IWD AND CMX TAF SITES THIS AFTERNOON TO THE KSAW TAF SITE. THIS WILL BE DO TO AN ADDITIONAL WIND SHIFT TO THE NORTH- NORTHEAST...ALLOWING FOR FAVORED UPSLOPE/LAKE EFFECT CONDITIONS FOR KSAW. THE NORTHEASTERLY WIND DIRECTION MAY ALLOW IWD TO SEE A REDUCTION IN LAKE EFFECT SNOW SHOWERS TONIGHT INTO SUNDAY...THEREFORE HAVE INCREASED THE VISIBILITY AND BUMPED THE CEILINGS UP SLIGHTLY. THIS MAY STILL CHANGE AS THE EXACT WIND DIRECTION WILL IMPACT THE OVERALL CEILING CONDTIONS AND LAKE EFFECT CHANCES AT IWD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 340 PM EST SAT JAN 31 2015 A COLD FRONT THAT SHIFTED SOUTH AND EAST OF THE AREA THIS AFTERNOON ALONG WITH A DECENT PRESSURE GRADIENT ON THE BACK SIDE WILL ALLOW A FEW GUSTS TO REACH 35KTS THIS AFTERNOON AND EVENING. MUCH LIGHTER WINDS WILL PREVAIL SUNDAY AS HIGH PRESSURE DRIFTS ACROSS THE UPPER GREAT LAKES REGION. LOW PRESSURE AND ASSOCIATED COLD FRONT WILL APPROACH THE AREA MONDAY NIGHT AND THEN SWEEP THROUGH THE AREA TUESDA NIGHT AND WEDNESDAY. ON THE BACK SIDE OF THIS SYSTEM...WINDS WILL INCREASE FROM THE NORTHWEST WEDNESDAY AFTERNOON THROUGH THURSDAY...WITH GALE FORCE GUSTS TO 35 KNOTS POSSIBLE. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 5 AM EST SUNDAY FOR LSZ264- 266-267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KEC LONG TERM...JLA AVIATION...KEC MARINE...KEC
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1147 PM EST FRI JAN 30 2015 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 406 PM EST FRI JAN 30 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL TROUGH FROM HUDSON BAY INTO THE NE CONUS RESULTING IN NW FLOW THROUGH THE NRN GREAT LAKES. AN UPSTREAM SHORTWAVE TROUGH WAS LOCATED OVER SRN MANITOBA. THE SHRTWV AND ASSOCIATED WAA PATTERN SUPPORTED SOME LIGHT SNOW FROM FAR NRN MN INTO NW ONTARIO WITH VSBY INTO THE 1-3SM RANGE. AT THE SFC...A RIDGE EXTENDED FROM THE MID MS VALLEY INTO THE WRN GREAT LAKES. BACKING WINDS TO SW OVER WRN LAKE SUPERIOR AND W OVER THE ERN LAKE HAVE PUSHED THE LES BANDS OFFSHORE EXCEPT FOR SOME LINGERING FLURRIES NEAR GRAND MARAIS. TONIGHT...EXPECT MID/HIGH CLOUDS TO THICKEN INTO THIS EVENING AS THE AS THE SHRTWV APPROACHES. UPSTREAM TRENDS AND MODELS FCST 285K-290K ISENTROPIC LIFT...SUGGESTS THAT THE AREA OF LIGHT SNOW WILL SPREAD THROUGH UPPER MICHIGAN BTWN 03Z-09Z. WITH LITTLE MOISTURE AVAILABLE AND DRY LOW LEVELS DELAYING THE ONSET OF THE PCPN...QPF OF 0.05 OR LOWER WITH SLR VALUES NEAR 20/1 WOULD ONLY RESULT IN SNOW AMOUNTS OF AN INCH OR LESS. HOWEVER...AS LOW LEVEL CONV INCREASES ALONG THE SFC FRONT/TROUGH AND 850 MB TEMPS DROP TO AROUND -12C...THERE MAY BE A BRIEF PERIOD OF LAKE ENHANCED SNOW INTO NW UPPER MI THAT MAY BRING TOTALS INTO THE 1 TO 2 INCH RANGE. SAT...THE AREA OF LOW LEVEL CONV WITH THE FRONT WILL SLIDE THROUGH THE REST OF THE NRN CWA WITH THE POTENTIAL FOR A NARROW BAND OF MODERATE SNOW. ALTHOUGH 850 MB TEMPS DROP TO NEAR -20C BY 00Z SUN...A QUICK TRANSITION TO A MORE DIFFLUENT/ANTICYCLONIC LOW-LVL NORTHERLY FLOW AND FALLING INVERSIONS AT OR BELOW 4KFT WILL LIMIT LES INTENSITY THE REST OF THE DAY. SNOW ACCUMULATIONS OF ONLY AROUND AN INCH ARE EXPECTED. AFTER MIDDAY HIGHS RANGING FROM THE TEENS NW TO MID TO UPPER 20S SCNTRL...TEMPS WILL DURING THE AFTERNOON AS BRISK N TO NW WINDS USHER ARCTIC AIR MASS INTO THE AREA. GUSTY WINDS WILL ALSO CREATE BLSN IN OPEN AREAS NEAR LAKE SUPERIOR. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 424 PM EST FRI JAN 30 2015 COLD WEATHER PATTERN IN STORE FOR MUCH OF EXTENDED. TEMPS WILL BE MUCH BLO NORMAL...ESPECIALLY FOR DAYTIME HIGHS. NORMAL HIGHS FOR FIRST PORTION OF FEBRUARY ARE IN THE LOWER TO MIDDLE 20S...AND THERE WILL BE A FEW DAYS NEXT WEEK WHERE HIGHS STAY BLO 10 ABOVE. TROUGHING ALOFT EXPANDS FM NORTHERN CANADA OVER GREAT LAKES AND MOST OF THE EASTERN CONUS AS RIDGING TEMPORARILY BUILDS OVER THE WEST COAST. LEAD SHOT OF ARCTIC AIR DROPS OVER GREAT LAKES SECOND HALF OF THE WEEKEND WITH H85/5KFT AGL TEMPS BLO -20C/-3F. ANOTHER STRONGER PUSH OF COLDER AIR IS DUE IN THE MIDDLE OF THE WEEK AS H85 TEMPS DROP TO AT LEAST -25C/-13F. COULD BE A WIDESPREAD SNOW JUST AHEAD OF THAT REINFORCING COLD FRONT TUESDAY NIGHT INTO WEDNESDAY. SINCE THE RIDGING OVER THE WEST COAST IS NOT THAT SHARP...WESTERN RIDGE AND EASTERN TROUGH PATTERN BREAKS DOWN BY NEXT WEEKEND WITH TEMPS MODERATING BACK TOWARD NORMAL...POSSIBLY ABOVE...BY NEXT WEEKEND. COLD FRONT MOVES EAST OF THE AREA ON SATURDAY NIGHT. ARCTIC HIGH PRESSURE BUILDS FM THE CANADIAN PRAIRIES TO THE NORTHERN PLAINS. RIDGING EXTENDS NORTH OF LK SUPERIOR WITH CONFLUENT FLOW ALOFT. SOUNDINGS INDICATE INVERSIONS 4 TO POSSIBLY 6 KFT WITH DELTA T/S INCREASING FM AROUND 18C SATURDAY EVENING TO 25C BY SUNDAY MORNING. MAJORITY OF DGZ NOT WITHIN LAKE CONVECTIVE LAYER...SO SNOWFLAKE SIZE AND THUS SLR/AMOUNTS WILL BE HELD DOWN TO AROUND 20:1 OR EVEN LOWER. LOW-LEVEL WINDS START OUT NNW-N ON SATURDAY EVENING AND TURN TO NNE BY SUNDAY AS RIDGING EXPANDS NORTH OF LK SUPERIOR. SETUP FAVORS LES WITH MAINLY LIGHT ACCUMS FOR FAR WEST CWA AND OVER THE NCNTRL CWA. SOUNDINGS INDICATE POSSIBLE WEAK LAKE ENHANCED SETUP AS SWATH OF H7- H5 MOISTURE MOVES ACROSS SATURDAY EVENING INTO SUNDAY MORNING. EXTENT OF DRYING BTWN THE MID-LEVEL MOISTURE AND LAKE CONVECTIVE LAYER MAY BE TOO MUCH TO OVERCOME THOUGH AS LIFT ALOFT IS WEAK. LOW- LEVEL CONVERGENCE VCNTY OF NORTH CENTRAL UPR MICHIGAN MAY MAKE UP FOR OVERALL MARGINAL SETUP FOR LES...BUT EVEN SO...DO NOT EXPECT MORE THAN A FEW INCHES OF SNOW SATURDAY NIGHT INTO SUNDAY FOR FAVORED AREAS. WINDS ARE NOT VERY STRONG...SO SNOW SHOWERS MAY TRY TO STAY CONFINED TOWARD THE SHORE INSTEAD OF SETTING UP OVER THE HIGHER TERRAIN. DESPITE THE ARRIVAL OF THE ARCTIC AIR...WINDS SHOULD NOT BE TOO STRONG...LIMITING THE OVERALL IMPACT. TEMPS SATURDAY NIGHT SHOULD FALL WELL BLO ZERO OVER THE EAST WITH DRAINAGE FLOW OFF ONTARIO. OTHERWISE...NE FLOW AND WEALTH OF STRATUS OFF LK SUPERIOR BENEATH A SUBSIDENCE INVERSION WILL RESTRICT TEMPS FM FALLING BLO ZERO. STRATUS SHOULD STAY IN PLACE FOR MUCH OF SUNDAY...EXCEPT OVER THE FAR EAST. HIGHS ON SUNDAY WILL STAY IN THE SINGLE DIGITS AND MAY JUST STRUGGLE ABOVE ZERO IN THE FAR EAST CWA. ARRIVAL OF ANOTHER SHORTWAVE FM THE NORTHWEST ACROSS THE PLAINS WILL BRING A SWATH OF SNOW TO AS CLOSE AS NORTHERN WI LATE SATURDAY NIGHT. THAT SYSTEM PHASES WITH ANOTHER MOVING OUT OF THE REMNANT OF CURRENT SOUTHWEST CONUS LOW TO PROVIDE WIDESPREAD SNOW ON SUNDAY ALONG DEVELOPING SFC LOW OVER MAINLY SOUTHERN PORTIONS OF WISCONSIN AND MICHIGAN. LOOKS LIKE UPR MICHIGAN WILL MISS THIS STORM SYSTEM. EXPECT LINGERING WEAKENING LES FOR SNOW BELTS TO EAST OF MARQUETTE AND POSSIBLY OVER THE NORTHWEST CWA. LES WILL CONTINUE TO DRIFT MAINLY OFFSHORE ON SUNDAY NIGHT AS WINDS IN BLYR SLOWLY BACK TO THE WEST ON EDGE OF HIGH PRESSURE SINKING OVER THE MIDDLE MISSISSIPPI RIVER VALLEY. CHILLY TEMPS FOR SUNDAY NIGHT WELL BLO ZERO...ESPECIALLY IN THE WEST INTERIOR AND ALSO EAST CWA WITH CONTINUATION OF LOW-LEVEL FLOW OFF ONTARIO. SINCE WINDS ARE LIGHT AND CALM...NO WIND CHILL ISSUES ARE EXPECTED. LES DRIFTS FARTHER EAST TO SNOW BELTS EAST OF MUNISING AND LIKELY INCREASES ON THE KEWEENAW AS WINDS BECOME MORE CONVERGENT FM THE WEST. SETUP THEN MAY BECOME FAVORABLE FOR MODERATE TO POSSIBLY HEAVY LAKE ENHANCED SNOW FOR NORTHERN KEWEENAW LATE MONDAY INTO TUESDAY MORNING AS WSW FLOW RESULTS IN STRONG CONVERGENCE BAND TO FORM WHILE SHORTWAVE WITH ADDITIONAL MID-LEVEL LIFT AND MOISTURE SLIDES ACROSS. SOUNDINGS INDCIATE THAT INVERSIONS REACH MORE TOWARD 8KFT WITH INVERSION TOP TEMPS NEARING -24C. POTENTIAL FOR HEAVY SNOW WITH RATES OVER 1 INCH PER HOUR WILL GREATLY DEPEND ON WHERE SHARPEST CONVERGENCE ALLIGNS. TOUGH TO TELL THAT AT THIS POINT WHERE THAT OCCURS...BUT WORTH AN HWO MENTION AS THIS TYPE OF LES PATTERN CAN RESULT IN A LOT OF SNOW IN JUST A FEW HOURS. ON INTO TUESDAY...LOW PRESSURE SYSTEM WILL BE ADVANCING ACROSS THE NORTHERN PLAINS. AREA OF H7-H5 Q-VECTOR CONVERGENCE TO THE NORTH AND EAST OF THE LOW AND AREA OF DIVERGENCE IN RIGHT ENTRANCE REGION OF JET STREAK SLIDING OVER THE UPPER GREAT LAKES SHOULD SPREAD AN AREA OF LGT SNOW WEST TO EAST ACROSS THE WESTERN GREAT LAKES. WENT WITH LOW POPS AWAY FM LAKE EFFECT AREAS...ESPECIALLY AS THE ECMWF KEEPS MOST WIDESRPEAD QPF SOUTH OF UPR MICHIGAN. LOW PRESSURE SYSTEM SHOULD BE JUST EAST OF UPR MICHIGAN WEDNESDAY MORNING WITH STRONGER COLD FRONT POISED TO SWEEP ACROSS. EXPECT NW FLOW LAKE EFFECT TO RAMP UP WEDENSDAY AFTN AS NEW SURGE OF COLD AIR RETURN TO THE AREA. ECMWF/GFS VARYING ON HOW COLD IT GETS AT H85. BLEND OF 12Z RUNS SUGGEST H85 TEMPS END UP AROUND -27C/-17F WHICH WITH LAKE TEMPS IN ICE FREE AREAS AROUND 2C/35F YIELDS PLENTY OF OVER-WATER INSTABILITY. ALSO...COMPARED TO THE RECENT LAKE EFFECT EVENTS...THE FORECAST SOUNDINGS INDICATE INVERSIONS MAY CLIMB TOWARD 8KFT. DUE TO THE COLD AIR...SLR/S WILL BE LOWER...BUT WHATEVER LES OCCURS WILL BE EFFICIENT AT REDUCING VSBY. SEEMS THAT SOME HAZARDS FOR THE SNOW AND BLSN MAY BE NEEDED AND LOW VSBY AFFECT WOULD ONLY BE ENHANCED DUE TO THE ICE COVER NEAR THE SHORELINE OF LK SUPERIOR. WILL MENTION THIS IN THE HWO. WILL BE AROUND WIND CHILL ADVISORY CRITERIA FOR AT LEAST WESTERN CWA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING AS TEMPS DROP TOWARD 10 BELOW AND WINDS ARE AT LEAST 5-10 MPH FM THE NW. ELSEWHERE...NW FLOW OFF LK SUPERIOR WILL MODERATE TEMPS AND KEEP WIND CHILLS ABOVE 20 BELOW. LES DIMINISHES AND EVENTUALLY ENDS BY NEXT FRIDAY AS WINDS BACK SW WITH HIGH PRESSURE DROPPING ACROSS THE CENTRAL PLAINS. COLD FOR ALL ON FRIDAY MORNING WITH MOST AREAS BLO ZERO...BUT WINDS SHOULD BE LIGHT ENOUGH TO RESTRICT WIND CHILL ISSUES AT THAT TIME. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SATURDAY NIGHT) ISSUED AT 1146 PM EST FRI JAN 30 2015 A TROUGH OVER NW MN WILL CROSS CENTRAL LAKE SUPERIOR BY 12Z. LOOK FOR -SN TO PICK UP IN INTENSITY ALONG AND BEHIND THE FRONT AND CONDITIONS AT SAW AND IWD WILL BE MVFR AND STAY THERE THROUGH THE REST OF THE FORECAST PERIOD. LES AND GUSTY WINDS PRODUCING BLSN AND LOWER VSBY INTO IFR CATEGORY IS EXPECTED AT CMX OVERNIGHT BEFORE GOING TO MVFR BY AFTERNOON. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 424 PM EST FRI JAN 30 2015 BRIEF LULL IN STRONGER WINDS OVER LK SUPERIOR ATTM AS HIGH PRESSURE DRIFTS ACROSS. STRONG COLD FRONT CROSSING ON SATURDAY WILL BRING IN ANOTHER SURGE OF STRONG WINDS...POSSIBLY REACHING 35 KT GALES SATURDAY AFTN INTO SATURDAY EVENING. LEFT THE GALE WATCH UP AS IT IS ONLY A MARGINAL SETUP FOR GALES. MID SHIFT CAN MAKE THE FINAL CALL. DID PUT UP HEAVY FREEZING SPRAY WARNING AS THAT IS MORE CERTAIN. WINDS BECOME LIGHT BY SUNDAY AS HIGH PRESSURE DRIFTS ACROSS. WINDS INCREASE FM THE WSW ON MONDAY NIGHT AHEAD OF ANOTHER LOW PRESSURE AND COLD FRONT THAT SWEEP OVER THE AREA ON TUESDAY NIGHT AND WEDNESDAY. BEHIND THAT FRONT...ANOTHER PERIOD OF GALES AND HEAVY FREEZING SPRAY IS EXPECTED INTO THURSDAY. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... GALE WATCH FROM SATURDAY AFTERNOON THROUGH SATURDAY EVENING FOR LSZ264-266-267. HEAVY FREEZING SPRAY WARNING FROM NOON SATURDAY TO 5 AM EST SUNDAY FOR LSZ264-266-267. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLA
AREA FORECAST DISCUSSION
NWS DULUTH MN
600 AM CST SAT JAN 31 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 348 AM CST SAT JAN 31 2015 MAIN CONCERNS IN THE SHORT TERM REMAIN FOCUSED AROUND THE LIGHT SNOW SHOWERS ACROSS NORTH CENTRAL WISCONSIN TODAY...WITH A BETTER CHANCE OF LIGHT ACCUMULATING LAKE EFFECT SNOW ALONG THE SOUTH SHORE FROM THE TWIN PORTS TO ASHLAND TONIGHT THROUGH SUNDAY. ALSO CONCERNED ABOUT THE VERY COLD TEMPERATURES AND POTENTIALLY DANGEROUS WIND CHILLS EXPECTED ALONG AND NORTH OF THE IRON RANGE TONIGHT/SUN MORNING. UPPER SHORT WAVE AND ASSOCIATED SFC TROUGH ARE CURRENTLY MOVING NW TO SE ACROSS THE REGION THIS MORNING WITH NW WINDS PICKING UP AND A FAIRLY COLD AIR MASS FILTERING IN BEHIND THE FRONT. TEMPERATURES WILL BE SLOWLY FALLING OR REMAINING STEADY THROUGH THE DAY WITH HIGHS IN THE SINGLE DIGITS AND TEENS IN NE MN AND INTO THE UPPER TEENS AND LOWER 20S IN NW WI. THE CAA ALOFT WILL AID IN THE CONTINUOUS CLOUD COVER OVER MUCH OF THE NORTHLAND TODAY WITH A SLIGHT ENHANCEMENT OF LAKE SNOW SHOWERS AROUND THE SNOW BELT REGION OF NRN WI. ONLY LIGHT OR TRACE AMTS OF SNOW ARE EXPECTED TODAY. THE ARCTIC AIR MASS WILL BEGIN TO IMPINGE UPON THE NORTHLAND FROM THE NORTH TONIGHT WITH 850MB TEMPS -15 TO -25 DEG C MOVING INTO THE BORDERLAND AREA AND THE TIP OF THE ARROWHEAD. SKIES WILL CLEAR OUT OVER THE NRN COUNTIES TONIGHT AND ALLOW SURFACE TEMPERATURES TO FALL INTO THE TEENS AND LOWER 20S BELOW ZERO...WITH LIGHT NORTH WINDS PRODUCING WIND CHILLS BELOW -30 F. WIND CHILL ADVISORIES MAY BE NEEDED. AS THIS COLD AIR MASS DROPS IN AND A POTENT WINTER STORM SYSTEM TRACKS EWD THROUGH THE MID MS VALLEY AND SRN GREAT LAKES AREA TONIGHT...FAVORABLE N/NE WINDS WILL DEVELOP ACROSS WRN LAKE SUPERIOR AND BEGIN TO FORM LAKE EFFECT SNOW SHOWERS ALONG THE SOUTH SHORE. HAVE INCREASED POPS AND THE POTENTIAL FOR LIGHT ACCUMULATING SNOW FROM THE TWIN PORTS EWD TO ASHLAND THROUGH SUNDAY WITH UP TO 3 INCHES OF SNOW POSSIBLE. HIGHER AMTS ARE NOT OUT OF THE QUESTION IF A LAKE BAND SETS UP OVER THE SAME AREA FOR AN EXTENDED PERIOD OF TIME. DRIER AIR WILL BEGIN TO MOVE IN FROM THE WEST LATE SUN AFTERNOON. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 348 AM CST SAT JAN 31 2015 THE PERIOD WILL BE RELATIVELY QUIET WITH REGARDS TO STRONG SYSTEMS PRODUCING SIGNIFICANT SNOWFALL. IT WILL MOSTLY BE COLD WITH HIGHS FROM 5 TO NEARLY 15 DEGREES BELOW NORMAL. SUNDAY NIGHT AND MONDAY WILL BE DRY FOR MOST AREAS AS HIGH PRESSURE MOVES SOUTHEAST OF THE REGION AND A TROUGH OF LOW PRESSURE MOVES IN FOR MONDAY. WE INCREASED CLOUD COVER MONDAY BUT LEFT THE MENTION OF SNOW OUT. FORECAST SOUNDINGS SHOW A FAIRLY DRY LOW LAYER THAT SUPPORTS NO MENTION SNOW ATTM. AN AREA OF LOW PRESSURE WILL TRACK FROM THE NORTHERN PLAINS THROUGH THE CENTRAL PLAINS MONDAY NIGHT INTO TUESDAY EVENING. THERE IS SOME DISAGREEMENT ON THE TRACK OF THIS SYSTEM...BUT ALL THE MODELS DO HAVE A SOLUTION FAR ENOUGH SOUTH TO KEEP SIGNIFICANT SNOWFALL OUT OF THE NORTHLAND. THE EXCEPTION WOULD BE SOME LAKE EFFECT ALONG THE SOUTH SHORE. A REINFORCING SHOT OF COLD AIR WILL MOVE IN TUESDAY/TUESDAY NIGHT AS HIGH PRESSURE BUILDS SOUTH INTO THE NORTHERN PLAINS BEHIND THE DEPARTING LOW. THE COLDER AIR AND NORTHWEST WINDS WILL BRING A CHANCE FOR SNOW SHOWERS ALONG THE SOUTH SHORE TUESDAY/TUESDAY NIGHT. OUTSIDE OF SOME LAKE EFFECT CHANCES...WE WENT WITH A DRY FORECAST FOR THE REST OF THE PERIOD FROM WEDNESDAY INTO FRIDAY. THERE ARE SOME INDICATIONS THAT WE MAY NEED TO ADD SOME POPS ON FRIDAY...BUT WE WILL WAIT FOR BETTER MODEL CONTINUITY BEFORE ADDING. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 600 AM CST SAT JAN 31 2015 MVFR CONDITIONS COVERED THE NORTHLAND EARLY THIS MORNING WITH SOME SNOW SHOWERS OCCURRING OVER FAR NORTHERN MINNESOTA. THE RAP HAS A DECENT HANDLE ON THE CURRENT CLOUD TRENDS...AND GRADUALLY SHOWS CLEARING FROM NORTH TO SOUTH. THE LOW LEVEL FLOW WILL VEER THROUGH THE DAY TO NORTH TO NORTHEAST AND WILL CAUSE THE CLOUDS TO LINGER LONGER OVER ALL BUT KINL. WE DID DELAY THE IMPROVEMENT TO VFR AT ALL TAF SITES. AS THE LOW LEVEL FLOW BECOMES MORE NORTHEAST...LAKE INDUCED CLOUDS AND PERHAPS SOME LIGHT SNOW WILL OCCUR ALONG THE SOUTH SHORE AND AS FAR SOUTH AND WEST AS KHYR/KDLH TONIGHT. THE AIRMASS WILL BE QUITE DRY...BUT THE FETCH IS LONG AND LOW LEVEL STABILITY LOW WITH 850MB TEMPS DROPPING TO AROUND -18C ALONG THE SOUTH SHORE. WE MAY NEED TO LOWER VSBYS AT KDLH WITH LATER UPDATES...BUT THAT WILL BE A SHORTER TERM ISSUE. && .PRELIMINARY POINT TEMPS/POPS... DLH 16 -1 8 -8 / 10 30 10 0 INL 5 -19 1 -19 / 0 0 0 0 BRD 18 -1 8 -5 / 10 10 10 0 HYR 21 3 10 -11 / 10 10 10 0 ASX 20 6 9 -7 / 30 60 50 10 && .DLH WATCHES/WARNINGS/ADVISORIES... MN...NONE. WI...NONE. LS...NONE. && $$ SHORT TERM...BJT LONG TERM...MELDE AVIATION...MELDE
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
815 PM CST SUN FEB 1 2015 .UPDATE...COLD FRONT TRIGGERING ALL THE LATE-DAY THUNDERSTORM ACTIVITY ACROSS THE REGION IS NOW PUSHING THROUGH SOUTHEAST MS. STILL HAVE ANOTHER HOUR TO GO BEFORE THE RISK OF SEVERE WEATHER IS ENTIRELY DONE IN FAR SOUTHEASTERN PORTIONS OF THE CWA...BUT EVEN THERE THE RISK HAS DWINDLED A LOT OWING TO DIMINISHING OF MARGINAL INSTABILITY. A FEW SHOWERS WILL REMAIN POSSIBLE BEHIND THE SURFACE FRONT AND IN THE WAKE OF THUNDERSTORMS...BUT EXPECT BEFORE MIDNIGHT ALL RAIN WILL HAVE CLEARED THE REGION. BUT THE COLD UPPER TROUGH STILL REMAINS TO PASS ACROSS THE REGION...AND LOOKS TO DO SO VERY LATE TONIGHT INTO JUST AFTER DAYBREAK. THE BRUNT OF HEIGHT FALLS AND UPPER LIFT ASSOCIATED WITH THIS PASSAGE WITH BE CONFINED NORTH OF OUR AREA WHERE SOME INCONSEQUENTIAL FLURRIES COULD BE SQUEEZED OUT. IT STILL IS IN THE REALM OF POSSIBILITY FLURRIES COULD OCCUR AS FAR SOUTH AS THE GOLDEN TRIANGLE...SO THIS ASPECT WAS KEPT IN THE FORECAST. AS FAR AS TEMPS GO...TEMPERATURES UPSTREAM IN THE WAKE OF THE COLD FRONT ARE DRASTICALLY COLDER AND HEADED THIS WAY. OF COURSE SOME MODERATION OF THESE UPSTREAM TEMPS WILL OCCUR BEFORE FILTERING INTO OUR REGION...BUT THE RECENT HRRR RUNS SEEMS TO BE TAKING INTO ACCOUNT OBSERVATIONAL TRENDS FOR TONIGHT BETTER (AS FAR AS BEING COLDER). LOWS WERE TRENDED DOWN A LITTLE (ESPECIALLY ACROSS SOUTHEASTERN PORTIONS OF THE MS). WITH GUSTY NORTHWEST WINDS THROUGH THE NIGHT AND FALLING TEMPS IT IS NOT OUT OF THE QUESTION THAT WIND CHILLS IN PORTIONS OF THE ARKLAMISS DELTA COULD BRIEFLY SNEAK INTO THE TEENS. THIS IS NOTHING WORTHY OF AN ADVISORY...JUST SOMETHING TO KEEP IN THE MIND. /BB/ && .PREV DISCUSSION... /ISSUED 333 PM CST SUN FEB 1 2015/ DISCUSSION...TONIGHT THROUGH SUNDAY...THE MAIN WEATHER IMPACT THROUGH THE SHORT TERM IS THE COLD FRONT THAT IS CURRENTLY SITUATED FROM NORTHWEST MISSISSIPPI INTO EAST CENTRAL TEXAS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG THE LINE AND AND THIS ACTIVITY WILL MOVE ACROSS THE ARKLAMISS INTO THE EVENING HOURS. DECENT FORCING COMBINED WITH MU CAPES OF AROUND 200-500 J/KG AND 0-6KM SHEAR OF 60KTS WILL ALLOW FOR STRONG TO SEVERE STORMS THIS AFTERNOON AND EVENING. THE WINDS BECOME MORE UNIDIRECTIONAL AS THE BOUNDARY APPROACHES SO EXPECT THE TORNADO POTENTIAL TO BE VERY LIMITED...WITH THE MAIN CONCERN BEING DAMAGING WIND GUSTS AND POSSIBLY HAIL TO THE SIZE OF QUARTERS WITH STORMS ALONG THE BOUNDARY. A LIMITED RISK FOR STRONG TO SEVERE STORMS IS CURRENTLY IN THE HWO FOR MUCH OF THE AREA THIS AFTERNOON THROUGH MID EVENING. THE BOUNDARY WILL MOVE TO THE EAST OF THE AREA BY LATE EVENING WITH SOME LIGHT POST FRONTAL SHOWERS AND POSSIBLY A FEW FLURRIES IN THE NORTHEAST DURING THE OVERNIGHT HOURS AS COLD AIR ADVECTION INCREASES AND TEMPS DROP. COOL HIGH PRESSURE WILL BUILD OVER THE AREA ON MONDAY WITH HIGHS ONLY CLIMBING INTO 40S FOR MOST OF THE AREA. A COLD NIGHT IS ON TAP MONDAY NIGHT AS HIGH PRESSURE REMAINS OVER THE AREA AND RADIATIONAL COOLING PREVAILS WITH LOWS FALLING INTO THE MID 20S. LITTLE WILL CHANGE ON TUESDAY WITH HIGH PRESSURE RIDGING CONTINUING TO PREVAIL...BUT THE SURFACE FLOW WILL BEGIN TO TURN AROUND TO THE SOUTH AND TEMPERATURES WILL BE A LITTLE WARMER WITH HIGHS IN THE 50S. BY WEDNESDAY A SHORT WAVE WILL MOVE ACROSS EAST TEXAS INTO LOUISIANA AND CURRENTLY THE GLOBAL MODELS SUGGEST THAT MOISTURE WILL INCREASE OUT AHEAD OF IT WITH SHOWERS POSSIBLE MAINLY SOUTH OF I-20 DURING THE AFTERNOON SPREADING NORTHWARD WEDNESDAY NIGHT. THE ECMWF/GEM ARE FURTHER NORTH THAN THE GFS WITH THE SHORT WAVE AND MOISTURE...SO WILL LEAN TOWARDS THE ECMWF. EXPECT MOST OF THE PRECIPITATION TO MAINLY BE LIGHT WITH THE HEAVIEST ACCUMULATIONS OVER THE SOUTHERN PORTIONS OF THE AREA. THE SHORT WAVE WILL MOVE EAST OF THE AREA WEDNESDAY NIGHT. ON THURSDAY A COLD FRONT WILL DIVE SOUTH ACROSS THE AREA BRINGING WITH IT LIGHT SHOWERS AND MUCH COLDER AIR. THE ECMWF SUGGEST POSSIBLY A MIXED BAG OF SNOW AND RAIN POSSIBLE THURSDAY AFTERNOON/EVENING AS THE UPPER TROUGH MOVES ACROSS THE AREA...BUT WITH THE TIMING OF IT DURING THE AFTERNOON HOURS WILL HOLD OFF ON THAT FOR NOW AND KEEP THE PRECIP LIQUID. HIGH PRESSURE WILL BUILD IN AND PREVAIL FOR THE REMAINDER OF THE PERIOD WITH WARMING TEMPERATURES BY SUNDAY./15/ && .AVIATION...EXPECT SCATTERED TO BROKEN CLOUD DECKS IN THE 2 TO 4 KFT (OCCASIONALLY MVFR) RANGE AT MOST TAF SITES UNTIL A FEW HOURS AFTER DAYBREAK TOMORROW. AFTER THAT POINT VFR CONDITIONS SHOULD PREVAIL LATER TOMORROW INTO TOMORROW NIGHT. GUSTY NORTHWEST WINDS TONIGHT INTO EARLY TOMORROW SHOULD LIGHTEN UP SOME HEADING INTO TOMORROW AFTERNOON AND THEN TREND MORE LIGHT AND VARIABLE HEADED INTO TOMORROW NIGHT. CURRENT SHOWERS AND STORMS IN MAINLY SOUTHEASTERN MS WILL BE GONE BY MIDNIGHT. /BB/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 34 42 26 53 / 25 6 0 2 MERIDIAN 35 46 25 54 / 68 9 0 3 VICKSBURG 32 43 24 54 / 8 5 0 2 HATTIESBURG 37 50 26 56 / 83 7 0 3 NATCHEZ 32 42 26 53 / 27 5 0 3 GREENVILLE 31 40 26 51 / 9 7 0 2 GREENWOOD 31 40 24 51 / 10 10 0 2 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/15
AREA FORECAST DISCUSSION
NWS BILLINGS MT
326 PM MST SAT JAN 31 2015 .SHORT TERM...VALID FOR SUN AND MON... SNOW THROUGH THIS EVENING IS THE MAIN SHORT TERM FORECAST CONCERN AS ROADS WILL BE SLIPPERY IN PLACES...ESPECIALLY AFTER SUNSET. SNOW RAPIDLY FILLED IN AND INTENSIFIED OVER MUCH OF SOUTHERN MT EARLY THIS AFTERNOON AS THE PEAK OF THE FORCING TIED TO THE MID- AND UPPER-LEVEL SHORTWAVE TROUGH BEGAN TO CROSS THE AREA. WE FEEL THE SNOW WILL WIND DOWN DURING THE EVENING AS THAT FORCING EXITS STAGE RIGHT INTO THE DAKOTAS...BUT RECENT HIGH-RESOLUTION MODEL GUIDANCE AND THE COARSER 12 UTC GFS AND TO A LESSER EXTENT THE ECMWF STILL SUPPORT EVENT TOTALS OF 1 TO 2 INCHES IN MANY SPOTS BY EVENING. WE WERE SOMEWHAT CONCERNED ABOUT HIGHER-THAN-EXPECTED SNOW TOTALS IN AND NEAR BILLINGS GIVEN RADAR TRENDS THROUGH 2130 UTC...WHICH HAD AN OROGRAPHIC SNOW BAND FROM LAVINA TO BROADVIEW AND DOWNSTREAM TO THE METRO AREA. A MORE CONTEMPORARY TREND IN RADAR DATA IS FOR THAT BAND TO DIMINISH THOUGH...WHICH IS A TREND SUPPORTED BY THE DEPARTURE OF LARGER-SCALE FORCING ALOFT. WE HAVE THUS STAYED THE COURSE WITH THE IDEA THAT TOTAL SNOW ACCUMULATION IN BILLINGS WILL BE AN INCH OR LESS. AFTERNOON RADAR IMAGERY ALSO ALSO SUPPORTED TODAY/S HRRR AND HIGH-RESOLUTION WRF-NMM AND WRF- ARW RUNS FOR A MODEST UPSLOPE-AIDED ENHANCEMENT OF SNOW IN THE RED LODGE FOOTHILLS WHERE WE ARE NOW CALLING FOR 2 TO 3 INCHES OF SNOW THROUGH THIS EVENING. DESPITE RELATIVELY LOW SNOW AMOUNTS PRECLUDING US FROM ISSUING ANY HEADLINES FOR THIS EVENT...ROADS WILL BECOME SLIPPERY BY EVENING IN AREAS WHERE THEY AREN/T ALREADY AS THE LACK OF SOLAR RADIATION AFTER SUNSET WILL ALLOW ROAD SURFACES TO DROP BELOW FREEZING AND ANY MOISTURE ON THEM TO FREEZE. THAT IS OUR MAIN FORECAST MESSAGE. BY SUNDAY...FLOW ALOFT TURNS ANTICYCLONIC WHILE SHORTWAVE RIDGING MOVES OVERHEAD AND THAT WILL LEAD TO A DRY DAY WITH HIGHS POSSIBLY HELD A BIT LOWER THAN THEY WOULD BE OTHERWISE BY FRESH SNOW COVER. THE 12 UTC MODEL SUITE REMAINED CONSISTENT IN SHOWING A WARM FRONT MOVING EASTWARD ACROSS THE REGION SUNDAY NIGHT INTO MONDAY AND WE ARE CARRYING SOME POPS IN THE FORECAST WITH THAT FEATURE...THOUGH FORCING LOOKS WEAK AND WILL LIKELY BE GREATEST IN SOUTHEASTERN MT TO THE EAST OF BILLINGS ON MONDAY MORNING WHERE WARM AIR ADVECTION ALOFT WILL BE FOCUSED. HIGHS MONDAY WILL JUMP BACK UP WELL INTO THE 40S F ON THE WARM SIDE OF THAT FRONT IN SOUTH CENTRAL MT AND NORTH CENTRAL WY. ITS PLACEMENT IS UNCLEAR THOUGH...AND BECOMES EVEN MORE UNCERTAIN COME MONDAY NIGHT WHEN IT IS LIKELY TO WAFFLE BACK SOUTHWARD AGAIN /AT LEAST BY THE 12 UTC GFS AND ECMWF...NOT THE NAM/. WE USED A BLEND OF CONTINUITY AND THE FORMER TWO MODELS TO LEAVE SOME HIGH-CHANCE TO LOW-END LIKELY POPS IN THE FORECAST BY LATE MONDAY NIGHT ACROSS PARTS OF THE AREA SINCE THE FRONTAL ZONE COULD FAVOR PRODUCTION OF SOME LIGHT SNOW. SCHULTZ .LONG TERM...VALID FOR TUE...WED...THU...FRI...SAT... DID MAKE SOME CHANGES TO THE EXTENDED FORECAST...AND THE CONCENTRATION OF THESE WERE IN THE EARLIER PART OF THE PERIOD. NORTHWEST FLOW IS PROGGED OVER THE AREA...WITH A STRONG SHORTWAVE ROTATING INTO NORTH DAKOTA TUESDAY AND TUESDAY NIGHT. THIS WILL PUSH A REINFORCING SHOT OF COLD AIR INTO THE AREA. MODELS HAVE BACKED OFF SOME ON THE DEPTH OF THE COLD AIR AND THUS GUIDANCE WAS WARMER. THE BULK OF THE COLDER AIR WAS SHOVED TO THE EAST. BUMPED TEMPERATURES UP A BIT BASED ON BASED ON MODEL TRENDS FOR TUESDAY AND MAINTAINED ON WEDNESDAY. MODELS WERE DIFFERENT ON QPF SOLUTIONS AS THE GFS WAS WETTER EARLIER THAN THE ECMWF AND THE ECMWF HOLDING ONTO PRECIPITATION LONGER INTO WEDNESDAY. BUMPED POPS FOR TUESDAY AS LOOKS GOOD FOR AN OVERRUNNING EVENT MONDAY NIGHT INTO TUESDAY NIGHT WITH A DECENT BAROCLINIC ZONE INVOLVED AND SOME PACIFIC MOISTURE AVAILABLE. SHOULD THE ECMWF VERIFY...MAY HAVE TO RAISE POPS INTO WEDNESDAY AND THURSDAY WITH PERSISTENT MID LEVEL WARM ADVECTION. LEFT THE REST OF THE FORECAST IN TACT AS AN UPPER RIDGE BUILDS IN FOR THE END OF THE WEEK WITH WEAK ENERGY RIDING OVER THE TOP. WINDS COULD BECOME STRONG AT LIVINGSTON AND NYE THURSDAY AND THURSDAY NIGHT AS ENERGY FLATTENS THE RIDGE. TWH && .AVIATION... AREAS OF LIGHT SNOW WITH POCKETS OF MODERATE SNOW WILL CONTINUE ACROSS MOST OF THE AREA THIS AFTERNOON. THE HEAVIER SNOW SHOWERS WILL LOWER CONDITIONS TO IFR AND LIFR. THE SNOW WILL TAPER OFF THIS EVENING...WITH THE SNOW TAPERING OFF SLOWER OVER SOUTHEAST MONTANA AND ALONG THE EAST SLOPES. CONDITIONS WILL IMPROVE TO VFR OVERNIGHT. MOUNTAINS WILL BE OBSCURED. TWH && .PRELIMINARY POINT TEMP/POPS... SUN MON TUE WED THU FRI SAT ----------------------------------------------------------- BIL 014/031 029/046 028/030 015/033 026/045 036/053 038/056 60/B 21/E 55/J 52/J 21/B 01/N 11/N LVM 016/040 031/049 035/035 021/039 029/049 036/054 039/055 40/B 31/N 44/W 43/W 21/E 11/N 21/N HDN 012/030 023/043 024/028 008/032 018/043 030/051 030/054 80/B 22/S 55/J 42/J 21/B 01/B 11/B MLS 007/023 020/034 018/019 000/023 012/038 025/046 027/052 91/B 24/O 65/J 20/B 11/B 11/B 12/W 4BQ 009/027 022/043 025/026 007/030 019/044 029/054 034/058 +1/B 23/O 54/J 31/B 11/B 01/B 12/W BHK 005/018 013/032 016/016 000/020 012/036 025/045 028/050 +1/B 24/S 54/J 20/B 10/B 11/B 12/W SHR 012/028 021/046 025/027 013/032 020/044 029/055 031/055 61/B 21/E 22/J 52/J 11/B 00/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
949 AM MST SAT JAN 31 2015 .UPDATE... THE GOING FORECAST APPEARS TO BE ON TRACK...SO WE ONLY MADE A FEW SMALL CHANGES WITH THIS UPDATE...NAMELY TO INCREASE POPS UP TO 100 PERCENT FROM MILES CITY TO BAKER THIS AFTERNOON AND TO INCREASE POST-FRONTAL WIND SPEEDS A BIT IN MOST AREAS BASED ON THE OBSERVED SURFACE PRESSURE RISES UPSTREAM AS OF 16 UTC. RADAR TRENDS SUPPORT SNOW SPREADING SOUTH AND EAST THIS AFTERNOON AS MODEL GUIDANCE HAS BEEN AND STILL IS SIMULATING...WITH THE GREATEST ACCUMULATIONS OF AN INCH OR TWO IN SOUTHEASTERN MT WHERE QG-FORCING IS STRONGEST. ONE ITEM THAT WE WILL BE INVESTIGATING FURTHER TODAY IS WHETHER OR NOT THE FOOTHILLS LIKE RED LODGE AND FISHTAIL COULD GET MORE SNOW THAN CURRENTLY FORECAST. RECENT HRRR RUNS SUPPORT ENOUGH QPF FOR A COUPLE INCHES THERE...LIKELY IN PART BECAUSE THAT MODEL IS FED BY THE GFS ON THE LARGE-SCALE AND THE GFS IS MORE SUPPORTIVE OF UPSLOPE SNOW THAN ITS ECMWF GLOBAL COUNTERPART. WE WILL WATCH THE OBSERVATIONAL TRENDS AND DIGEST ADDITIONAL MODEL GUIDANCE BEFORE ADJUSTING THAT PART OF THE FORECAST BASED ON THOSE DISPARITIES. SCHULTZ && .SHORT TERM...VALID FOR TDY AND SUN... COLD FRONT MOVING INTO NORTHERN MONTANA THIS MORNING BUT NOT VERY ARCTIC LIKE WITH TEMPERATURES ONLY DOWN TO 18 DEGREES AT CALGARY. HOWEVER ITS A BIG AIRMASS CHANGE FROM WE HAVE BEEN EXPERIENCING AND TEMPERATURES WILL BECOME MUCH COLDER TODAY DURING THE AFTERNOON HOURS. AHEAD OF THE FRONTAL ARRIVAL THERE IS A PATCH OF STRATUS THAT IS TRYING TO PROGRESS INTO NORTHERN SECTIONS OF SOUTHEAST MONTANA BUT CLOUD COVER IS CAUSING IT SLOW ITS MOVEMENT. STILL EXPECT THIS STRATUS TO GET CLOSE TO A BAKER TO MILES CITY LINE BY SUNRISE AND SOME PATCHES OF FREEZING FOG ARE EXPECTED. FRONT WILL PROGRESS THROUGH THE AREA FROM NORTH TO SOUTH THROUGH THE LATE MORNING AND EARLY AFTERNOON HOURS WITH ITS PROGRESS A BIT FASTER THROUGH SOUTHEAST MONTANA. MODELS SHOW LIGHT SNOW DEVELOPING MAINLY IN THE POST FRONTAL AREA IN SOUTHEAST MONTANA AS SHORTWAVE ENERGY TRACKS OVER THE AREA LATER IN THE DAY. HRRR SHOWS ANOTHER AREA OF SNOW DEVELOPING IN THE BILLINGS AREA AND LOCATIONS 30 MILES SOUTH AND WEST AS UPSLOPE PLAYS A FACTOR IN PROVIDING LIFT. THIS WINDOW FOR SNOW ALREADY DISSIPATES BY MIDNIGHT AS HEIGHTS BEGIN TO BUILD ALOFT AND THE COLD AIR PUSH BEGINS TO TRANSLATE EAST. GIVEN THE SHORT WINDOW AND NOT A STRONG ALIGNMENT FOR LIFT CONFIDENT SNOW AMOUNTS WILL BE LIGHT AND GENERALLY AROUND AN INCH THOUGH A FEW LOCATIONS COULD SEE CLOSER TO 2. BIGGER THREAT IS THE SNOW FALLING ON WARM ROADS AND MELTING AND FREEZING. THIS STILL LOOKS REASONABLE ESPECIALLY IF A FEW HOURS OF SUNSHINE OCCUR BEFORE THE FRONT. CURRENT IR IMAGERY INDICATES THIS IS LIKELY ESPECIALLY FOR THE WESTERN HALF OF THE AREA. TEMPERATURES WILL BE FALLING FROM THE MID TO UPPER 30S THIS MORNING THROUGH THE 20S THIS AFTERNOON. LOWS WILL SETTLE IN THE 5 TO 15 DEGREE RANGE OVERNIGHT. COLD BY COMPARISON TO THIS PAST WEEK BUT NOT DRAMATIC FOR JANUARY. SUNDAY THE AIRMASS MODERATES AS THE DEEPER COLD AIR MOVES AWAY FROM THE REGION WITH A WARM FRONT MOVING INTO THE WESTERN ZONES BY LATE AFTERNOON AND ACROSS THE AREA SUNDAY NIGHT. MOST OF THE DAY WILL BE DRY BUT THE WARM FRONT DOES INCREASE MOISTURE OVER THE WESTERN ZONES WHICH WILL BRING A CHANCE FOR MOUNTAINS SNOW. BORSUM .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... LITTLE IN THE WAY OF CHANGES TO THE EXTENDED FORECAST PERIOD...AS THE OVERALL STORY REMAINS THE SAME. COLDER AND UNSETTLED WEATHER TO START THE WORK WEEK...WITH A RETURN TO ABOVE SEASONAL AVERAGE TEMPERATURES TO END THE WEEK. MODELS CONTINUE TO HAVE TIMING DIFFERENCES FOR ARCTIC INTRUSION...BUT GENERAL CONSENSUS POINTS TOWARD BEST PRECIP POTENTIAL ON TUESDAY AFTERNOON/EVENING. ONE TREND THAT SEEMS TO PERSIST OVER THE PAST FEW MODEL RUNS IS A LOWER QPF TYPE EVENT...FOR BOTH THE GFS AND THE ECMWF...SO HEAVY SNOW IS LESS LIKELY. UPPER LEVEL RIDGING BEGINS PUSHING INTO THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING. THE RIDGE DOMINATES THE PATTERN THROUGH THE REMAINDER OF THE PERIOD...KEEPING GENERALLY DRY CONDITIONS IN PLACE. THERE DO APPEAR TO BE SEVERAL SHORTWAVES SLIPPING THROUGH THE FLOW HOWEVER...BRINGING PERIODIC POTENTIAL FOR MOUNTAIN SHOWERS THROUGH THE PERIOD. A STRONGER WAVE PUSHES INTO THE REGION SATURDAY...WITH PLENTY OF ASSOCIATED PACIFIC MOISTURE...WHICH SHOULD BRING SHOWERS ACROSS THE REGION. AAG && .AVIATION... A COLD FRONT WILL MARCH THROUGH THE AREA THIS MORNING. THIS FRONT WILL PRODUCE NORTH TO NORTHEAST WINDS...WITH SOME GUSTS TO 20KTS IN THE FIRST FEW HOURS OF PASSAGE. THE FRONT WILL ALSO DRAG SOME LOW STRATUS AND FOG INTO EASTERN SECTIONS IMPACTING KMLS AND KBHK WITH OCCASIONAL IFR AND LIFR CONDITIONS. SOME LIGHT FREEZING DRIZZLE IS POSSIBLE EAST OF KBIL THIS MORNING AS THE FRONT MOVES IN TOO. LIGHT SNOW WILL DEVELOP BY THIS AFTERNOON OVER THE AREA WITH SOME CONDITIONS LOWERING TO IFR...ESPECIALLY EAST OF KBIL AND ALONG THE EAST SLOPES. MOUNTAINS WILL BE OBSCURED. THE SNOW WILL TAPER OFF THIS EVENING. TWH && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 037 014/032 029/045 028/028 012/028 021/043 033/053 6/S 71/E 23/W 55/J 42/J 21/B 11/N LVM 039 016/038 032/047 034/040 020/035 026/046 034/055 2/O 51/N 33/W 46/J 42/J 21/B 11/N HDN 036 010/030 024/043 024/028 006/026 015/041 026/051 6/S 61/B 23/W 55/J 41/B 21/B 11/B MLS 029 007/024 020/035 018/019 000/019 009/035 023/047 +/S 61/B 24/J 55/J 21/B 11/B 11/B 4BQ 041 009/028 022/043 025/029 007/023 016/042 027/055 3/O 71/B 23/W 34/J 41/B 11/B 11/B BHK 025 003/020 015/033 016/019 901/014 005/034 022/046 +/S 81/B 24/J 54/J 21/B 11/B 11/B SHR 039 011/029 021/044 025/036 009/030 015/042 026/053 1/N 31/B 22/W 25/J 52/J 21/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
928 AM MST SAT JAN 31 2015 .SHORT TERM...FOR NORTHEAST MONTANA...TODAY THROUGH MONDAY... SHORT TERM MODELS APPEAR TO HAVE AN EXCELLENT HANDLE ON THE DEVELOPMENT OF SNOW OVER THE AREA WITH HRRR FORECASTS MATCHING THE REFLECTIVITY PATTERN QUITE WELL. HEAVIEST PERIOD OF SNOW WILL LAST THROUGH 20Z WITH LIGHTER MORE SCATTERED AMOUNTS TRAILING OFF THROUGH 12Z TOMORROW. SNOW AMOUNTS HAVE BEEN AROUND AN INCH SO FAR BUT BLOWING SNOW HAS REDUCED VISIBILITY DOWN TO 1/4 MILE IN PLACES. COLD AND WIND HAS GENERATED SMALL DRY SNOW PARTICLES WHICH WILL BLOW AND DRIFT DURING THE DAY. TEMPERATURES WILL CONTINUE TO DECLINE THROUGH THE DAY REACHING SINGLE DIGITS BY SUNDAY MORNING. UPDATED FORECAST FOR WINDS AS OBSERVATIONS HAVE BEEN RUNNING A LITTLE HIGH. MARTIN PREVIOUS DISCUSSION... LOW CLOUD AND FOG SPREADING SOUTHWEST ACROSS THE REGION. SHORTWAVE PUSHING INTO NORTH CENTRAL MONTANA WITH SNOW STILL NORTH OF THE CANADIAN BORDER. AS THE WAVE TRACKS THROUGH THE STATE TODAY...SNOW WILL SPREAD SOUTHWARD...DISSIPATING THE FOG ALTHOUGH VISIBILITY WILL REMAIN LOW WITH THE FALLING SNOW. ENOUGH GRADIENT WIND TO PRODUCE SOME DRIFTING SNOW THIS AFTERNOON...BEFORE DIMINISHING THIS EVENING. SNOWFALL ALSO EXPECTED TO TAPER OFF THROUGH THE NIGHT. CURRENT ADVISORY STILL LOOKS ON TRACK WITH 2 TO 3 INCHES OF SNOW EXPECTED TODAY...WITH AN ADDITIONAL INCH OR TWO TONIGHT. COLD AIR LINGERS INTO SUNDAY AS CANADIAN HIGH SLIDES THROUGH THE NORTHERN PLAINS. WEAK SHORTWAVE DROPPING THROUGH THE STATE SUNDAY NIGHT SHIFTS ARCTIC BOUNDARY ACROSS CENTRAL MONTANA AND COULD PRODUCE A LITTLE OVERRUNNING SNOW ON MONDAY MORNING. EBERT .LONG TERM...MONDAY NIGHT THROUGH SATURDAY... THE EXTENDED FORECAST PERIOD BEGINS WITH NORTHWEST FLOW ALOFT OVER NORTHEAST MONTANA. THERE WILL BE A MODERATE RIDGE OFF THE WEST COAST AND AN ARCTIC LOW CENTERED OVER HUDSON BAY BUT WITH A MASSIVE COLD AIR MASS SPREAD OVER MOST OF CANADA. A WAVE MOVING AROUND THE WESTERN SIDE OF THE LOW SENDS A COLD FRONT FURTHER SOUTH INTO THE LOCAL REGION. A QUICK-MOVING SHORT-WAVE CROSSES THE DIVIDE AND BECOME THE FOCUS OF PRECIPITATION MONDAY NIGHT AND TUESDAY. AN INVERTED SURFACE TROUGH SUGGESTS QPF OF GREATER THAN 0.10 INCH. WX TYPE WILL LIKELY BE ALL SNOW...BUT THERE ARE HINTS IN THE MODEL THAT SOME COULD BE IN THE FORM OF FREEZING RAIN MIXED IN AT TIMES. MODEL QPF PRODUCES AROUND 3-4 INCHES OF SNOW FOR TUESDAY. SO THIS IS A STORM TO WATCH. A SURFACE HIGH SLIDES INTO THE AREA TUESDAY EVENING TO CUT OFF ANY REMAINING SNOW. NEMONT WILL REMAIN ON THE COLD SIDE OF THE STATIONARY BOUNDARY WITH MODIFIED ARCTIC AIR THAT WILL KEEP TEMPERATURES SOMEWHERE NEAR NORMAL THROUGH THURSDAY. THEN AN UPPER RIDGE AXIS MOVES ACROSS THE DIVIDE TO BRING A WARM FRONT THROUGH NEMONT WHICH WILL RAISE TEMPERATURES ABOVE NORMAL FOR FRIDAY AND SATURDAY. WHAT IS UNCERTAIN IS WHETHER OR NOT A DISTURBANCES RUNS THROUGH THE REGION AFTER IT WARMS. THE GFS IS MORE ROBUST WITH A WAVE THAN THE EC. SO THERE COULD BE SOME MIXED PRECIPITATION BY THE WEEKEND. SCT && .AVIATION... AN UPPER LEVEL TROUGH MOVES EAST THROUGH THE AREA TODAY AS A COLD FRONT DESCENDS SOUTH FROM CANADA BRINGING SNOW AND LOW CLOUDS FOR IFR/LIFR CEILINGS AND VISIBILITIES AS LOW AS ONE-QUARTER MILE AT TIMES. AIRPORT MINIMUMS ARE MOST LIKELY THIS MORNING THROUGH THIS AFTERNOON. STRONG EASTERLY TO NORTHEASTERLY WINDS WILL BEGIN TO TAPER OFF LATE IN THE DAY. WIND WILL EASILY GENERATE AREAS OF BLOWING SNOW. EXPECT CONDITIONS TO IMPROVE BY SUNDAY MORNING. BMICKELSON && .GLASGOW WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 5 AM MST SUNDAY FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...DANIELS... DAWSON...EASTERN ROOSEVELT...GARFIELD...MCCONE...NORTHERN PHILLIPS...NORTHERN VALLEY...PRAIRIE...RICHLAND...SHERIDAN... SOUTHWEST PHILLIPS...WESTERN ROOSEVELT...WIBAUX. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION
NWS BILLINGS MT
306 AM MST SAT JAN 31 2015 .SHORT TERM...VALID FOR TDY AND SUN... COLD FRONT MOVING INTO NORTHERN MONTANA THIS MORNING BUT NOT VERY ARCTIC LIKE WITH TEMPERATURES ONLY DOWN TO 18 DEGREES AT CALGARY. HOWEVER ITS A BIG AIRMASS CHANGE FROM WE HAVE BEEN EXPERIENCING AND TEMPERATURES WILL BECOME MUCH COLDER TODAY DURING THE AFTERNOON HOURS. AHEAD OF THE FRONTAL ARRIVAL THERE IS A PATCH OF STRATUS THAT IS TRYING TO PROGRESS INTO NORTHERN SECTIONS OF SOUTHEAST MONTANA BUT CLOUD COVER IS CAUSING IT SLOW ITS MOVEMENT. STILL EXPECT THIS STRATUS TO GET CLOSE TO A BAKER TO MILES CITY LINE BY SUNRISE AND SOME PATCHES OF FREEZING FOG ARE EXPECTED. FRONT WILL PROGRESS THROUGH THE AREA FROM NORTH TO SOUTH THROUGH THE LATE MORNING AND EARLY AFTERNOON HOURS WITH ITS PROGRESS A BIT FASTER THROUGH SOUTHEAST MONTANA. MODELS SHOW LIGHT SNOW DEVELOPING MAINLY IN THE POST FRONTAL AREA IN SOUTHEAST MONTANA AS SHORTWAVE ENERGY TRACKS OVER THE AREA LATER IN THE DAY. HRRR SHOWS ANOTHER AREA OF SNOW DEVELOPING IN THE BILLINGS AREA AND LOCATIONS 30 MILES SOUTH AND WEST AS UPSLOPE PLAYS A FACTOR IN PROVIDING LIFT. THIS WINDOW FOR SNOW ALREADY DISSIPATES BY MIDNIGHT AS HEIGHTS BEGIN TO BUILD ALOFT AND THE COLD AIR PUSH BEGINS TO TRANSLATE EAST. GIVEN THE SHORT WINDOW AND NOT A STRONG ALIGNMENT FOR LIFT CONFIDENT SNOW AMOUNTS WILL BE LIGHT AND GENERALLY AROUND AN INCH THOUGH A FEW LOCATIONS COULD SEE CLOSER TO 2. BIGGER THREAT IS THE SNOW FALLING ON WARM ROADS AND MELTING AND FREEZING. THIS STILL LOOKS REASONABLE ESPECIALLY IF A FEW HOURS OF SUNSHINE OCCUR BEFORE THE FRONT. CURRENT IR IMAGERY INDICATES THIS IS LIKELY ESPECIALLY FOR THE WESTERN HALF OF THE AREA. TEMPERATURES WILL BE FALLING FROM THE MID TO UPPER 30S THIS MORNING THROUGH THE 20S THIS AFTERNOON. LOWS WILL SETTLE IN THE 5 TO 15 DEGREE RANGE OVERNIGHT. COLD BY COMPARISON TO THIS PAST WEEK BUT NOT DRAMATIC FOR JANUARY. SUNDAY THE AIRMASS MODERATES AS THE DEEPER COLD AIR MOVES AWAY FROM THE REGION WITH A WARM FRONT MOVING INTO THE WESTERN ZONES BY LATE AFTERNOON AND ACROSS THE AREA SUNDAY NIGHT. MOST OF THE DAY WILL BE DRY BUT THE WARM FRONT DOES INCREASE MOISTURE OVER THE WESTERN ZONES WHICH WILL BRING A CHANCE FOR MOUNTAINS SNOW. BORSUM .LONG TERM...VALID FOR MON...TUE...WED...THU...FRI... LITTLE IN THE WAY OF CHANGES TO THE EXTENDED FORECAST PERIOD...AS THE OVERALL STORY REMAINS THE SAME. COLDER AND UNSETTLED WEATHER TO START THE WORK WEEK...WITH A RETURN TO ABOVE SEASONAL AVERAGE TEMPERATURES TO END THE WEEK. MODELS CONTINUE TO HAVE TIMING DIFFERENCES FOR ARCTIC INTRUSION...BUT GENERAL CONSENSUS POINTS TOWARD BEST PRECIP POTENTIAL ON TUESDAY AFTERNOON/EVENING. ONE TREND THAT SEEMS TO PERSIST OVER THE PAST FEW MODEL RUNS IS A LOWER QPF TYPE EVENT...FOR BOTH THE GFS AND THE ECMWF...SO HEAVY SNOW IS LESS LIKELY. UPPER LEVEL RIDGING BEGINS PUSHING INTO THE REGION WEDNESDAY NIGHT INTO THURSDAY MORNING. THE RIDGE DOMINATES THE PATTERN THROUGH THE REMAINDER OF THE PERIOD...KEEPING GENERALLY DRY CONDITIONS IN PLACE. THERE DO APPEAR TO BE SEVERAL SHORTWAVES SLIPPING THROUGH THE FLOW HOWEVER...BRINGING PERIODIC POTENTIAL FOR MOUNTAIN SHOWERS THROUGH THE PERIOD. A STRONGER WAVE PUSHES INTO THE REGION SATURDAY...WITH PLENTY OF ASSOCIATED PACIFIC MOISTURE...WHICH SHOULD BRING SHOWERS ACROSS THE REGION. AAG && .AVIATION... VFR CONDITIONS PERSIST ACROSS MUCH OF THE REGION THIS MORNING. IFR CEILINGS AND VISIBILITIES WITH LOW CLOUDS AND PATCHY FOG ARE POISED JUST NORTHEAST OF THE REGION...AND ARE ANTICIPATED TO SPREAD INTO SOUTHEAST MONTANA THIS MORNING. LIGHT FREEZING DRIZZLE IS POSSIBLE AT KMLS AND KBHK UNTIL THE CLOUD LAYER DEEPENS ENOUGH FOR LIGHT SNOW TO BEGIN BY SATURDAY AFTERNOON. EXPECT TO SEE CLOUD DECK DEVELOPING AND CONDITIONS LOWERING TO SUB- VFR LEVELS ACROSS THE AREA THIS AFTERNOON AS LIGHT SNOW DEVELOPS. AAG && .PRELIMINARY POINT TEMP/POPS... TDY SUN MON TUE WED THU FRI ------------------------------------------------------- BIL 038 014/032 029/045 028/028 012/028 021/043 033/053 6/S 71/E 23/W 55/J 42/J 21/B 11/N LVM 040 016/038 032/047 034/040 020/035 026/046 034/055 2/O 51/N 33/W 46/J 42/J 21/B 11/N HDN 036 010/030 024/043 024/028 006/026 015/041 026/051 6/S 61/B 23/W 55/J 41/B 21/B 11/B MLS 032 007/024 020/035 018/019 000/019 009/035 023/047 9/S 61/B 24/J 55/J 21/B 11/B 11/B 4BQ 042 009/028 022/043 025/029 007/023 016/042 027/055 3/O 71/B 23/W 34/J 41/B 11/B 11/B BHK 027 003/020 015/033 016/019 901/014 005/034 022/046 8/S 81/B 24/J 54/J 21/B 11/B 11/B SHR 040 011/029 021/044 025/036 009/030 015/042 026/053 1/N 31/B 22/W 25/J 52/J 21/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
800 PM CST SUN FEB 1 2015 .SYNOPSIS... ISSUED AT 316 PM CST SUN FEB 1 2015 H5 ANALYSIS THIS MORNING HAS A SHORTWAVE TROUGH OF LOW PRESSURE OVER THE MID MISSOURI VALLEY NEAR OMAHA. THIS FEATURE EXTENDS SOUTH INTO THE OZARKS AND ARKLATEX. A CUTOFF LOW WAS LOCATED OVER NORTHERN MEXICO WITH A RIDGE EXTENDING UP THE WEST COAST OF THE CONUS. FURTHER EAST...A TROUGH OF LOW PRESSURE EXTENDED FROM HUDSON BAY INTO THE CANADIAN MARITIMES. AT THE SURFACE...STRONG LOW PRESSURE WAS LOCATED OVER SRN ILLINOIS. HIGH PRESSURE WAS LOCATED OVER EASTERN NORTH DAKOTA. IN BETWEEN THESE TWO FEATURES...A NICE PRESSURE GRADIENT AND GUSTY WINDS WERE PRESENT ACROSS NEBRASKA. THIS HAS LED TO SOME BLOWING SNOW ISSUES TDY...MAINLY EAST OF HIGHWAY 83 FROM NORTH PLATTE TO VALENTINE. FURTHER WEST...WINDS HAVE BEGUN TO RELAX SOME...ESPECIALLY IN THE PANHANDLE. LIGHT SNOW CONTINUED OVER THE FAR EASTERN ZONES THIS AFTERNOON...AND A WINTER WEATHER ADVISORY REMAINS IN EFFECT ROUGHLY EAST OF A LINE FROM VALENTINE TO ARNOLD FOR SNOW AND BLOWING SNOW. UNDER CLEAR TO MOSTLY CLOUDY SKIES...READINGS AS OF 3 PM CST...RANGED FROM 4 ABOVE AT AINSWORTH AND ONEILL...TO 14 AT IMPERIAL. && .UPDATE... ISSUED AT 759 PM CST SUN FEB 1 2015 A LITTLE WORK 0N THE FORECAST TO LOWER TEMPERATURES TOWARD MESONET REPORTS PRODUCES AN AREA OF -20 TO -30 WIND CHILL READINGS TONIGHT. A WIND CHILL ADVISORY IS NOW IN EFFECT FOR PARTS OF WESTERN AND NORTH CENTRAL NEBRASKA. UPDATE ISSUED AT 559 PM CST SUN FEB 1 2015 WIND SPEEDS HAVE PEAKED AND ARE ON THE WAY DOWN TOWARD LIGHT AND VARIABLE BY 02Z. THE WINTER WEATHER ADVISORY WILL BE ALLOWED TO EXPIRE AT 6 PM CST. THE REST OF THE FORECAST IS ON TRACK. WE WILL BE WATCHING HOW QUICKLY TEMPERATURES TUMBLE AFTER SUNSET. THE FORECAST TONIGHT IS CLOSE TO THE RAP MODEL && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 WINTER STORM CONTINUES TO EXIT TO THE EAST. SHOULD SEE WINDS BEGIN TO DIMINISH IN THE NEXT FEW HOURS...AFTER SUNSET...AS WE DECOUPLE. RADAR RETURNS ARE DIMINISHING...AND SNOW/BLOWING SNOW WILL BECOME LESS OF A CONCERN. HOWEVER STILL HAVING A FEW REPORTS OF VISIBILITIES AROUND 1SM SO WILL CONTINUE THE ADVISORY UNCHANGED THROUGH 00Z. ON TOP OF THE SNOW/BLOWING SNOW IS THE CAA TAKING PLACE. TEMPS GENERALLY IN THE SINGLE DIGITS ACROSS ALL BUT THE SW ZONES. STRONGEST WINDS ARE OVER N CENTRAL...WHICH IS WERE TEMPS ARE AROUND 5 DEGREES. THE COMBINATION OF WINDS AND COLD TEMPS ARE PUSHING WIND CHILL VALUES NEAR -15 TO -20 DEGREES. THIS IS APPROACHING WIND CHILL ADVISORY LEVELS. WILL CONTINUE THE WSW FOR SNOW/BLSN AND INCLUDE THE MENTION OF WIND CHILLS EARLY THIS EVENING. THE CONCERN IS AS THE SNOW ENDS EXPECT SKIES TO CLEAR. 1035MB HIGH SETTLES OVERHEAD EARLY THIS EVENING. THIS WILL COMBINE WITH THE FRESH SNOW OF SEVERAL INCHES ACROSS MUCH OF THE AREA TO PRODUCE AN EXCELLENT RADIATIONAL COOLING ENVIRONMENT. TEMPS SHOULD QUICKLY TANK AS WINDS DIMINISH. WIND CHILLS COULD FALL/CONTINUE IN ADVISORY CATEGORY AFTER THE WINTER WX ADVISORY EXPIRES...BUT WILL KEEP IT SIMPLE AND ONLY HAVE ONE HEADLINE GOING FOR NOW AND LET THE EVENING SHIFT MODIFY. AS FOR LOWS...DROPPED BELOW COLDEST MET GUIDANCE AS TYPICAL FOR CLEAR SKIES AND LIGHT WINDS AS SYSTEM DEPARTS. MODELS SHIFT THE HIGH SE AFTER MIDNIGHT AND WAA BEGINS WITH SOUTHERLY WINDS ON THE INCREASE. THE BATTLE BETWEEN THE SNOW PACK AIDING IN A DECOUPLED BL VERSES RISING TEMPS WITH THE WAA. HAVE FOLLOWED THE GUIDANCE TREND AND BOTTOMED TEMPS AROUND MIDNIGHT WITH RISING TEMPS TOWARDS MORNING. THIS RAISED ANOTHER CONCERN ABOUT THE LENGTH NEEDED FOR A WIND CHILL ADVISORY. TOMORROW WAA ADVECTION CONTINUES WITH 850 MB TEMPS RISING TO OR ABOVE 0C FOR NEARLY ALL BY 18Z. SW NEB PUSHES TOWARDS 5C BY THE AFTERNOON. THE SNOW PACK WILL LIMIT MIXING...ALTHOUGH WINDS BECOME WESTERLY...DOWNSLOPING. DECIDED TO REMAIN CONSERVATIVE OVER ALL BUT THE SOUTHWEST AND HIGHER TERRAIN IN THE EASTERN PANHANDLE...AND KEPT TEMPS AT OR BELOW GUIDANCE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 MONDAY NIGHT THROUGH WEDNESDAY...AN ACTIVE MID RANGE PATTERN WILL CONTINUE INTO THE MIDWEEK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. THE PATTERN WILL BE HIGHLIGHTED BY A WARM FRONTAL PASSAGE MONDAY NIGHT INTO EARLY TUESDAY...FOLLOWED BY AN ARCTIC COLD FRONT AND MID LEVEL FRONT WEDNESDAY...WHICH WILL BRING SOME ACCUMULATING SNOWS TO THE FORECAST AREA. BEGINNING MONDAY NIGHT...ARCTIC HIGH PRESSURE WILL MOVE FROM THE EASTERN DAKOTAS INTO MINNESOTA. THIS WILL ALLOW A WARM FRONT TO LIFT ACROSS THE WEST AND CENTRAL CWA MONDAY NIGHT AND ACROSS THE EASTERN ZONES EARLY TUESDAY MORNING. AT THE SAME TIME...A WEAK IMPULSE WILL TRACK SOUTHEAST ACROSS SOUTH DAKOTA INTO NERN NEBRASKA. THOUGH THE MAIN ENERGY WITH THIS IMPULSE WILL BE ACROSS SOUTH DAKOTA INVOF THE ARCTIC FRONT...ON THE SRN PERIPHERY OF THE IMPULSE...WE COULD SEE SOME WEAK LIFT ALONG THE WARM FRONT EARLY TUESDAY. BUFKIT FCST SOUNDINGS ACROSS THE NORTHEASTERN CWA TUESDAY MORNING HAVE A THERMAL PROFILE...INDICATIVE OF LIGHT FREEZING PCPN/ALTERNATING WITH LIGHT SNOW. BASED ON THESE FACTORS...DECIDED TO INSERT A MENTION OF LIGHT SNOW OR LIGHT FZ RAIN IN THE NORTHEAST TUESDAY MORNING INVOF THE FRONT. AS FOR LOWS MONDAY NIGHT...GIVEN THE SNOW COVER PRESENT ACROSS THE FORECAST AREA...TRENDED LOWS TOWARD THE COOLER MET GUIDANCE. FOR TUESDAY...HIGHS WILL VARY WIDELY WITH READINGS IN THE LOWER 30S INVOF THE WARM FRONT ACROSS THE FAR NORTHEAST...TO THE LOWER 50S IN THE FAR SOUTHWEST. FOR LATE TUESDAY NIGHT INTO WEDNESDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE TO INDICATE A GOOD CHANCE FOR MEASURABLE SNOW ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS THE FORECAST AREA WEDNESDAY WHILE AN AREA OF STRONG MID LEVEL FRONTOGENESIS WILL TRAIL THE FRONT ACROSS THE CENTRAL CONUS. THE FORECAST CHALLENGE WITH THIS SYSTEM WILL BE THE FRONTAL TIMING AND THE POSSIBILITY OF SOME FREEZING PCPN IN ASSOCIATION WITH THE SURFACE FRONT. THE MID RANGE MODEL SOLUTIONS THIS MORNING WERE ABOUT 6 HRS APART WITH THEIR FRONTAL TIMING. THE GFS IS MORE AGGRESSIVE WITH THE FRONT WHILE THE NAM IS 6 HRS SLOWER. FOR THE FRONTAL TIMING...DECIDED TO COMPROMISE BETWEEN THE GFS AND NAM SOLNS FOR THE FRONTAL TIMING AND RESULTANT ONSET OF PRECIPITATION. WITH THIS IN MIND...TRIMMED BACK PRECIPITATION CHANCES TUESDAY EVENING TO THE FAR NORTHWEST. FOR OVERNIGHT TUESDAY AND WEDNESDAY...LITTLE CHANGE WAS MADE TO THE INHERITED GRIDS WITH 40 TO 50 POPS RETAINED WEDNESDAY. WITH RESPECT TO HIGHS WEDNESDAY...WITH BOTH MODELS CLEARING THE FRONT THROUGH THE FORECAST AREA BY LATE MORNING...HIGHS WILL BE EARLY WITH FALLING TEMPS THEREAFTER. FINALLY WITH RESPECT TO PTYPES...DECIDED TO INSERT A MENTION OF FREEZING RAIN ALONG THE LEADING EDGE OF THE ARCTIC FRONT AS CROSS SECTIONS ARE INDICATING A SMALL WINDOW OF WARMER AIR IMMEDIATELY BEHIND THE SURFACE ARCTIC FRONT. LONG RANGE...WEDNESDAY NIGHT THROUGH SUNDAY...ARCTIC HIGH PRESSURE WILL BUILD IN BEHIND THE ARCTIC FRONT WEDNESDAY EVENING...BEFORE SHIFTING INTO THE OZARKS OVERNIGHT. LOWS WILL BE VERY COLD WEDNESDAY NIGHT WITH READINGS RANGING FROM -4 IN THE EAST...TO AROUND 10 IN THE WEST. READINGS COLD BE COLDER...ESPECIALLY IF THE HIGH IS SLOWER TO MOVE OUT WEDS EVENING. BY THURSDAY...RIDGING ALOFT WILL PUSH INTO THE WESTERN CONUS...ALLOWING WARMER PACIFIC AIR TO PUSH INTO THE CENTRAL AND SRN PLAINS BEGINNING THURSDAY...AND CONTINUING THROUGH SUNDAY. HIGHS WILL REBOUND BACK INTO THE 30S THURSDAY...FOLLOWED BY 40S AND 50S FRIDAY...AND 50S SATURDAY AND SUNDAY. MAINLY DRY CONDS ARE EXPECTED IN THE LONG RANGE PERIODS...HOWEVER...THERE WILL BE A MINIMAL THREAT FOR RAIN OR SNOW SATURDAY NIGHT IN THE NORTH. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 522 PM CST SUN FEB 1 2015 VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH MONDAY AFTN. MIDLEVEL CLOUDINESS WILL OVERSPREAD THE REGION FROM WEST TO EAST MONDAY MORNING THROUGHOUT THE AFTN. CIGS AS LOW AS 6KFT ARE INDICATED IN THE MODELS AND THE NAM SUGGESTS A FAST MOVING PERIOD OF FLURRIES WITH NO REDUCTION IN VISIBILITY. && .LBF WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ MONDAY FOR NEZ004>010-023>029-038-094. && $$ UPDATE...CDC SYNOPSIS...CLB SHORT TERM...MASEK LONG TERM...CLB AVIATION...CDC
AREA FORECAST DISCUSSION...UPDATED
NWS NORTH PLATTE NE
559 PM CST SUN FEB 1 2015 .SYNOPSIS... ISSUED AT 316 PM CST SUN FEB 1 2015 H5 ANALYSIS THIS MORNING HAS A SHORTWAVE TROUGH OF LOW PRESSURE OVER THE MID MISSOURI VALLEY NEAR OMAHA. THIS FEATURE EXTENDS SOUTH INTO THE OZARKS AND ARKLATEX. A CUTOFF LOW WAS LOCATED OVER NORTHERN MEXICO WITH A RIDGE EXTENDING UP THE WEST COAST OF THE CONUS. FURTHER EAST...A TROUGH OF LOW PRESSURE EXTENDED FROM HUDSON BAY INTO THE CANADIAN MARITIMES. AT THE SURFACE...STRONG LOW PRESSURE WAS LOCATED OVER SRN ILLINOIS. HIGH PRESSURE WAS LOCATED OVER EASTERN NORTH DAKOTA. IN BETWEEN THESE TWO FEATURES...A NICE PRESSURE GRADIENT AND GUSTY WINDS WERE PRESENT ACROSS NEBRASKA. THIS HAS LED TO SOME BLOWING SNOW ISSUES TDY...MAINLY EAST OF HIGHWAY 83 FROM NORTH PLATTE TO VALENTINE. FURTHER WEST...WINDS HAVE BEGUN TO RELAX SOME...ESPECIALLY IN THE PANHANDLE. LIGHT SNOW CONTINUED OVER THE FAR EASTERN ZONES THIS AFTERNOON...AND A WINTER WEATHER ADVISORY REMAINS IN EFFECT ROUGHLY EAST OF A LINE FROM VALENTINE TO ARNOLD FOR SNOW AND BLOWING SNOW. UNDER CLEAR TO MOSTLY CLOUDY SKIES...READINGS AS OF 3 PM CST...RANGED FROM 4 ABOVE AT AINSWORTH AND ONEILL...TO 14 AT IMPERIAL. && .UPDATE... ISSUED AT 559 PM CST SUN FEB 1 2015 WIND SPEEDS HAVE PEAKED AND ARE ON THE WAY DOWN TOWARD LIGHT AND VARIABLE BY 02Z. THE WINTER WEATHER ADVISORY WILL BE ALLOWED TO EXPIRE AT 6 PM CST. THE REST OF THE FORECAST IS ON TRACK. WE WILL BE WATCHING HOW QUICKLY TEMPERATURES TUMBLE AFTER SUNSET. THE FORECAST TONIGHT IS CLOSE TO THE RAP MODEL && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 WINTER STORM CONTINUES TO EXIT TO THE EAST. SHOULD SEE WINDS BEGIN TO DIMINISH IN THE NEXT FEW HOURS...AFTER SUNSET...AS WE DECOUPLE. RADAR RETURNS ARE DIMINISHING...AND SNOW/BLOWING SNOW WILL BECOME LESS OF A CONCERN. HOWEVER STILL HAVING A FEW REPORTS OF VISIBILITIES AROUND 1SM SO WILL CONTINUE THE ADVISORY UNCHANGED THROUGH 00Z. ON TOP OF THE SNOW/BLOWING SNOW IS THE CAA TAKING PLACE. TEMPS GENERALLY IN THE SINGLE DIGITS ACROSS ALL BUT THE SW ZONES. STRONGEST WINDS ARE OVER N CENTRAL...WHICH IS WERE TEMPS ARE AROUND 5 DEGREES. THE COMBINATION OF WINDS AND COLD TEMPS ARE PUSHING WIND CHILL VALUES NEAR -15 TO -20 DEGREES. THIS IS APPROACHING WIND CHILL ADVISORY LEVELS. WILL CONTINUE THE WSW FOR SNOW/BLSN AND INCLUDE THE MENTION OF WIND CHILLS EARLY THIS EVENING. THE CONCERN IS AS THE SNOW ENDS EXPECT SKIES TO CLEAR. 1035MB HIGH SETTLES OVERHEAD EARLY THIS EVENING. THIS WILL COMBINE WITH THE FRESH SNOW OF SEVERAL INCHES ACROSS MUCH OF THE AREA TO PRODUCE AN EXCELLENT RADIATIONAL COOLING ENVIRONMENT. TEMPS SHOULD QUICKLY TANK AS WINDS DIMINISH. WIND CHILLS COULD FALL/CONTINUE IN ADVISORY CATEGORY AFTER THE WINTER WX ADVISORY EXPIRES...BUT WILL KEEP IT SIMPLE AND ONLY HAVE ONE HEADLINE GOING FOR NOW AND LET THE EVENING SHIFT MODIFY. AS FOR LOWS...DROPPED BELOW COLDEST MET GUIDANCE AS TYPICAL FOR CLEAR SKIES AND LIGHT WINDS AS SYSTEM DEPARTS. MODELS SHIFT THE HIGH SE AFTER MIDNIGHT AND WAA BEGINS WITH SOUTHERLY WINDS ON THE INCREASE. THE BATTLE BETWEEN THE SNOW PACK AIDING IN A DECOUPLED BL VERSES RISING TEMPS WITH THE WAA. HAVE FOLLOWED THE GUIDANCE TREND AND BOTTOMED TEMPS AROUND MIDNIGHT WITH RISING TEMPS TOWARDS MORNING. THIS RAISED ANOTHER CONCERN ABOUT THE LENGTH NEEDED FOR A WIND CHILL ADVISORY. TOMORROW WAA ADVECTION CONTINUES WITH 850 MB TEMPS RISING TO OR ABOVE 0C FOR NEARLY ALL BY 18Z. SW NEB PUSHES TOWARDS 5C BY THE AFTERNOON. THE SNOW PACK WILL LIMIT MIXING...ALTHOUGH WINDS BECOME WESTERLY...DOWNSLOPING. DECIDED TO REMAIN CONSERVATIVE OVER ALL BUT THE SOUTHWEST AND HIGHER TERRAIN IN THE EASTERN PANHANDLE...AND KEPT TEMPS AT OR BELOW GUIDANCE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 MONDAY NIGHT THROUGH WEDNESDAY...AN ACTIVE MID RANGE PATTERN WILL CONTINUE INTO THE MIDWEEK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. THE PATTERN WILL BE HIGHLIGHTED BY A WARM FRONTAL PASSAGE MONDAY NIGHT INTO EARLY TUESDAY...FOLLOWED BY AN ARCTIC COLD FRONT AND MID LEVEL FRONT WEDNESDAY...WHICH WILL BRING SOME ACCUMULATING SNOWS TO THE FORECAST AREA. BEGINNING MONDAY NIGHT...ARCTIC HIGH PRESSURE WILL MOVE FROM THE EASTERN DAKOTAS INTO MINNESOTA. THIS WILL ALLOW A WARM FRONT TO LIFT ACROSS THE WEST AND CENTRAL CWA MONDAY NIGHT AND ACROSS THE EASTERN ZONES EARLY TUESDAY MORNING. AT THE SAME TIME...A WEAK IMPULSE WILL TRACK SOUTHEAST ACROSS SOUTH DAKOTA INTO NERN NEBRASKA. THOUGH THE MAIN ENERGY WITH THIS IMPULSE WILL BE ACROSS SOUTH DAKOTA INVOF THE ARCTIC FRONT...ON THE SRN PERIPHERY OF THE IMPULSE...WE COULD SEE SOME WEAK LIFT ALONG THE WARM FRONT EARLY TUESDAY. BUFKIT FCST SOUNDINGS ACROSS THE NORTHEASTERN CWA TUESDAY MORNING HAVE A THERMAL PROFILE...INDICATIVE OF LIGHT FREEZING PCPN/ALTERNATING WITH LIGHT SNOW. BASED ON THESE FACTORS...DECIDED TO INSERT A MENTION OF LIGHT SNOW OR LIGHT FZ RAIN IN THE NORTHEAST TUESDAY MORNING INVOF THE FRONT. AS FOR LOWS MONDAY NIGHT...GIVEN THE SNOW COVER PRESENT ACROSS THE FORECAST AREA...TRENDED LOWS TOWARD THE COOLER MET GUIDANCE. FOR TUESDAY...HIGHS WILL VARY WIDELY WITH READINGS IN THE LOWER 30S INVOF THE WARM FRONT ACROSS THE FAR NORTHEAST...TO THE LOWER 50S IN THE FAR SOUTHWEST. FOR LATE TUESDAY NIGHT INTO WEDNESDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE TO INDICATE A GOOD CHANCE FOR MEASURABLE SNOW ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS THE FORECAST AREA WEDNESDAY WHILE AN AREA OF STRONG MID LEVEL FRONTOGENESIS WILL TRAIL THE FRONT ACROSS THE CENTRAL CONUS. THE FORECAST CHALLENGE WITH THIS SYSTEM WILL BE THE FRONTAL TIMING AND THE POSSIBILITY OF SOME FREEZING PCPN IN ASSOCIATION WITH THE SURFACE FRONT. THE MID RANGE MODEL SOLUTIONS THIS MORNING WERE ABOUT 6 HRS APART WITH THEIR FRONTAL TIMING. THE GFS IS MORE AGGRESSIVE WITH THE FRONT WHILE THE NAM IS 6 HRS SLOWER. FOR THE FRONTAL TIMING...DECIDED TO COMPROMISE BETWEEN THE GFS AND NAM SOLNS FOR THE FRONTAL TIMING AND RESULTANT ONSET OF PRECIPITATION. WITH THIS IN MIND...TRIMMED BACK PRECIPITATION CHANCES TUESDAY EVENING TO THE FAR NORTHWEST. FOR OVERNIGHT TUESDAY AND WEDNESDAY...LITTLE CHANGE WAS MADE TO THE INHERITED GRIDS WITH 40 TO 50 POPS RETAINED WEDNESDAY. WITH RESPECT TO HIGHS WEDNESDAY...WITH BOTH MODELS CLEARING THE FRONT THROUGH THE FORECAST AREA BY LATE MORNING...HIGHS WILL BE EARLY WITH FALLING TEMPS THEREAFTER. FINALLY WITH RESPECT TO PTYPES...DECIDED TO INSERT A MENTION OF FREEZING RAIN ALONG THE LEADING EDGE OF THE ARCTIC FRONT AS CROSS SECTIONS ARE INDICATING A SMALL WINDOW OF WARMER AIR IMMEDIATELY BEHIND THE SURFACE ARCTIC FRONT. LONG RANGE...WEDNESDAY NIGHT THROUGH SUNDAY...ARCTIC HIGH PRESSURE WILL BUILD IN BEHIND THE ARCTIC FRONT WEDNESDAY EVENING...BEFORE SHIFTING INTO THE OZARKS OVERNIGHT. LOWS WILL BE VERY COLD WEDNESDAY NIGHT WITH READINGS RANGING FROM -4 IN THE EAST...TO AROUND 10 IN THE WEST. READINGS COLD BE COLDER...ESPECIALLY IF THE HIGH IS SLOWER TO MOVE OUT WEDS EVENING. BY THURSDAY...RIDGING ALOFT WILL PUSH INTO THE WESTERN CONUS...ALLOWING WARMER PACIFIC AIR TO PUSH INTO THE CENTRAL AND SRN PLAINS BEGINNING THURSDAY...AND CONTINUING THROUGH SUNDAY. HIGHS WILL REBOUND BACK INTO THE 30S THURSDAY...FOLLOWED BY 40S AND 50S FRIDAY...AND 50S SATURDAY AND SUNDAY. MAINLY DRY CONDS ARE EXPECTED IN THE LONG RANGE PERIODS...HOWEVER...THERE WILL BE A MINIMAL THREAT FOR RAIN OR SNOW SATURDAY NIGHT IN THE NORTH. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 522 PM CST SUN FEB 1 2015 VFR IS EXPECTED ALL AREAS OVERNIGHT THROUGH MONDAY AFTN. MIDLEVEL CLOUDINESS WILL OVERSPREAD THE REGION FROM WEST TO EAST MONDAY MORNING THROUGHOUT THE AFTN. CIGS AS LOW AS 6KFT ARE INDICATED IN THE MODELS AND THE NAM SUGGESTS A FAST MOVING PERIOD OF FLURRIES WITH NO REDUCTION IN VISIBILITY. && .LBF WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...CDC SYNOPSIS...CLB SHORT TERM...MASEK LONG TERM...CLB AVIATION...CDC
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
325 PM CST SAT JAN 31 2015 .SHORT TERM...(TONIGHT THROUGH TUESDAY) ISSUED AT 325 PM CST SAT JAN 31 2015 SNOW AND HEADLINES ARE THE MAIN PROBLEMS IN THE SHORT TERM AND HAVE KEPT PRIMARY FOCUS IN THE NEXT 24-30 HOURS. A 90 KNOT JET MAX WAS ON THE FRONT SIDE OF THE TROUGH ACROSS THE SOUTHWEST US AT 12Z. ANOTHER AREA OF STRONG WINDS AT 300 MB WAS FROM NORTHERN MINNESOTA INTO THE OHIO VALLEY. LATEST WATER VAPOR IMAGERY AND RECENT RAP MODEL INITIALIZATIONS SHOW A CLOSED LOW DROPPING SOUTHWARD ACROSS BAJA. A MID LEVEL TROUGH WAS LOCATED FROM WESTERN NEBRASKA INTO EASTERN COLORADO AND ANOTHER WAVE WAS DROPPING SOUTHEAST FROM MONTANA. A 12 HOUR 500 MB HEIGHT FALL MAX OF ABOUT 130 METERS WAS OVER MONTANA AND ANOTHER AROUND 100 METERS WAS NEAR THE MEXICO/NEW MEXICO BORDER. SO THIS IS A FAIRLY COMPLEX SETUP... WITH SOME PHASING OF THE NORTHERN AND SOUTHERN STREAMS EXPECTED TONIGHT. MOISTURE HAS BEEN RETURNING OVER THE CENTRAL PLAINS WITH AREAS OF SNOW OR A MIX OF RAIN AND SNOW. WILL MAKE SOME MINOR CHANGES TO HEADLINES...ADDING A FEW COUNTIES TO THE WARNING IN THE NORTH. IMPRESSIVE MOISTURE (850-700 MB SPECIFIC HUMIDITY VALUES 3-4 G/KG AT 6 PM THIS EVENING...FALLING TO 2-3 G/KG BY 12Z SUNDAY) ALONG WITH GOOD FORCING SHOULD ALLOW FOR SNOW AMOUNTS FROM ABOUT 4 TO 9 INCHES IN MOST OF THE FORECAST AREA. HIGHEST SNOW AMOUNTS EXPECTED NORTH AND EAST. AS COLDER AIR SINKS IN FROM THE NORTH BEHIND THE COLD FRONT (WHICH EXTENDED FROM WISCONSIN BACK INTO SOUTHWEST NEBRASKA EARLY THIS AFTERNOON)...TEMPERATURES WILL FALL AND ROADS WILL START TO ICE UP/BECOME SNOW COVERED AND SLICK. TEMPERATURES SHOULD START SLIDING TONIGHT AND CONTINUE TO DROP THROUGH MUCH OF THE DAY SUNDAY. STRONG NORTH SURFACE WINDS WILL LIKELY ALSO CAUSE SOME BLOWING SNOW LATER TONIGHT AND AT LEAST THROUGH EARLY SUNDAY AFTERNOON. HEADLINES WILL CONTINUE UNTIL 6 PM SUNDAY IN NEBRASKA AND UNTIL 9 PM SUNDAY IN SOUTHWEST IOWA. IT IS POSSIBLE THESE MAY BE CANCELLED EARLIER THAN THAT...BUT THAT IS WHAT WE WILL GO WITH FOR NOW. SNOW AMOUNTS WILL DECREASE THROUGH THE DAY AS DRIER AIR MOVES IN FROM THE WEST AND LIFT PULLS OUT OF THE REGION. HIGH PRESSURE AT THE SURFACE BUILDS IN FOR SUNDAY NIGHT. WINDS WILL DECREASE AND WITH CLEARING SKIES HAVE LOWS FALLING OR AROUND ZERO...OR EVEN BELOW ZERO IN OUR NORTHERN COUNTIES. WARM AIR ADVECTION AND SOUTH WINDS SHOULD INCREASE MONDAY. KEPT A SMALL CHANCE OF SNOW NORTH AND NORTHEAST OF OMAHA...BUT NOT A BIG DEAL. A SLIGHTLY BETTER CHANCE OF SNOW ARRIVES FOR TUESDAY. 12Z GFS SEEMED A BIT TOO HIGH ON QPF TUESDAY...BUT WILL SEE HOW THINGS TREND NEXT FEW MODEL RUNS. .LONG TERM...(TUESDAY NIGHT THROUGH SATURDAY) ISSUED AT 325 PM CST SAT JAN 31 2015 LOOK FOR MODERATING TEMPERATURES THIS PERIOD. FAST WEST/NORTHWEST MID LEVEL FLOW WILL OCCUR EARLY...WITH A RIDGE DEVELOPING OVER THE WESTERN US. THIS RIDGE SHOULD BUILD EAST THROUGH THE WEEK. HIGHS WILL BE 20S WEDNESDAY AND THURSDAY RISING TO ABOVE NORMAL FOR FRIDAY AND SATURDAY. THERE IS SOME CHANCE OF LIGHT SNOW WEDNESDAY OTHERWISE IT SHOULD BE MAINLY DRY. && .AVIATION...(18Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1142 AM CST SAT JAN 31 2015 IFR CIGS HAVE SETTLED IN AT ALL THREE TAF SITES AS OF 18Z AND WILL LIKELY REMAIN SO FOR MUCH OF THIS FORECAST PERIOD. EXPECT LIFR CIGS FROM TIME TO TIME AT KOMA AND KLNK ALREADY. LOOK FOR LIGHT RAIN TO MOVE INTO THE KOFK AREA AFTER 19Z WHILE A RAIN SNOW MIX WILL CONTINUE AT KOMA AND A BETTER CHANCE OF MOSTLY RAIN SNOW MIX WILL CONTINUE AT KOMA. ALL SNOW HAS BEEN OCCURRING AT KLNK BUT EXPECT A CHANGE BACK TO A RAIN SNOW MIX AFTER 22Z. THEN OVERNIGHT...IN THE 02Z TO 04Z TIME RANGE...LOOK FOR CHANGEOVER TO ALL SNOW. HAVE BROUGHT IN PERIODS OF MODERATE SNOW WITH VISBY DOWN TO 1/2 SM AFTER 04Z. AFTER 11Z WINDS WILL HAVE SHIFTED TO THE NORTH AND WILL GUST TO 30KT OR BETTER. SNOW WILL TAPPER OFF AND BECOME LIGHTER IN NATURE...BUT COMBINED WITH BLOWING AND DRIFTING SNOW AFTER 12Z. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST SUNDAY FOR NEZ011-016-017-030>033-042>045-050>053-065>068- 078-088>093. WINTER STORM WARNING FROM 6 PM THIS EVENING TO 6 PM CST SUNDAY FOR NEZ012-015-018-034. IA...WINTER STORM WARNING FROM 6 PM THIS EVENING TO 9 PM CST SUNDAY FOR IAZ043-055-056-069-080-091. WINTER WEATHER ADVISORY FROM 6 PM THIS EVENING TO 6 PM CST SUNDAY FOR IAZ079-090. && $$ SHORT TERM...MILLER LONG TERM...MILLER AVIATION...MEYER
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1134 AM CST SAT JAN 31 2015 .SYNOPSIS... ISSUED AT 357 AM CST SAT JAN 31 2015 HIGH PRESSURE IS RIDGING SOUTH FROM MANITOBA INTO NORTH DAKOTA WHILE LOW PRESSURE EXTENDS FROM AZ INTO COLORADO. A GOOD FETCH OF PACIFIC MOISTURE AS WELL AS MODIFIED GULF MOISTURE IS BEING DRAWN NORTHWARD AHEAD OF THE LOW PRESSURE...RESULTING IN OVERCAST SKIES AND STRATUS INTO SOUTHERN NEBRASKA. SOME LIGHT RAIN OR RAIN/SNOW MIXED IS WORKING INTO SOUTH CENTRAL NEBRASKA AND A SMALL PART OF SWRN NEBR ATTM. TEMPERATURES HOLDING IN THE 30S ACROSS MOST OF NEBRASKA. && .UPDATE... ISSUED AT 1130 AM CST SAT JAN 31 2015 A BAND OF SNOW...LOCALLY AND BRIEFLY MIXED WITH RAIN...HAS DEVELOPED ACROSS PORTION OF THE SANDHILLS. THE BAND IS LIFTING TO THE NORTH SLOWLY. THE LATEST HRRR DIMINISHES THIS BAND OVER THE NEXT FEW HOURS THEN DEVELOPS THE MAIN BAND ACROSS NORTHERN NEBRASKA LATER THIS AFTERNOON. THERE IS A POCKET OF DRY AIR IN THE WATER VAPOR WHICH SHOULD BE ENOUGH TO DIMINISH THE CURRENT BAND. THE 12Z MODELS DO AGREE IN DEVELOPING THE MAIN BAND ACROSS NORTHERN NEBRASKA AND A FEW...ESPECIALLY THE NAM...HAS INCREASED THE QPF AMOUNTS. THE GFS AND THE MAJORITY OF THE SHORT TERM MODELS ARE NOT DEVELOPING AS MUCH AS THE NAM...HOWEVER THEY HAVE INCREASED THE START TIME AND EXPANDED THE BAND FURTHER WEST...THUS FELT IT WAS WARRANTED TO EXPAND THE ADVISORY WESTWARD AND START IT EARLIER...21Z. MAJOR CONCERN IS ABOUT THE QPF AMOUNTS /SNOW TOTALS WITH THIS SYSTEM. WILL CONTINUE TO MONITOR CLOSELY THE SHORT TERM MODEL UPDATES AND THE 18Z NAM RUN. SNOW TOTALS CURRENTLY EXPECTED ARE GENERALLY A 3 TO 6 INCH BAND IN THE ADVISORY...WHICH MAY BE CONSERVATIVE. IF THE NAM VERIFIES...AN UPGRADE TO A WARNING WOULD BE NEEDED. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 357 AM CST SAT JAN 31 2015 THE LOW PRESSURE SYSTEM ACROSS THE DESERT SOUTHWEST WILL BE DRAWN INTO KANSAS AND NEBRASKA TODAY AS A NRN STREAM TROUGH MOVES INTO THE NRN PLAINS. THIS WILL CAUSE AN H7 LOW TO DEVELOP INTO CENTRAL NEBRASKA BY 18Z. ISENTROPIC UPGLIDE WILL INCREASE TODAY WITH A TROWAL TO DEVELOP ACROSS THE NEBRASKA SANDHILLS ON THE NWRN PERIPHERY OF THE H7 LOW. MODEL ARE ALL IN GOOD AGREEMENT WITH THE PLACEMENT AND TIMING OF THIS FEATURE. SOUNDINGS SHOW A DRY LAYER NEAR 600MB WHICH WILL LIMIT PRECIP INITIALLY FROM REACHING THE GROUND. ISENTROPIC LIFT SHOULD BE ABLE TO SATURATE THE LAYER BY 18Z. HAVE SUBSTANTIALLY INCREASED POPS TO LIKELY ACROSS THE CENTRAL SANDHILLS AND DEFINITE BY LATE AFTERNOON. ANOTHER CONCERN WILL BE PRECIP TYPE. COOLER AIR FROM THE NORTHERN SYSTEM DRIFTS SOUTH...WHICH MODELS ARE IN AGREEMENT. KEPT MENTION AS RAIN OR SNOW THIS MORNING...THEN TO ALL SNOW BY MID AFTERNOON CENTRAL AND NORTHERN AREAS. A CHANGEOVER COULD OCCUR SOONER. ACROSS THE SOUTH KEPT MENTION AS RAIN OR SNOW THROUGH THE AFTERNOON. TEMPERATURES SHOULD REACH TO UPPER 30S TO NEAR 40 SOUTHWEST...WHILE FALLING INTO THE UPPER 20S MUCH OF THE NCTRL IN THE AFTN DUE TO DYNAMIC COOLING AND COOLER AIR DROPPING SOUTH. SNOW ACCUMULATIONS OF 1 TO 2 INCHES AND LOCALLY HIGHER ARE POSSIBLE ACROSS THE SANDHILLS THIS AFTERNOON...WHILE LITTLE OR NO ACCUMULATIONS EXPECTED IN THE SOUTH. HEAVIEST ACCUMULATIONS WILL BE TONIGHT ACROSS NCTRL NEBR...ESPECIALLY EAST OF VALENTINE TO BREWSTER WHERE TOTAL AMOUNTS OF 3 TO 5 INCHES AND LOCALLY HIGHER ARE POSSIBLE. THE TROWAL SHOULD REMAIN WELL DEFINED TONIGHT...ENHANCED BY THE APPROACHING NRN STREAM TROUGH. NORTH WINDS INCREASING TO 15 TO 25 MPH LATE THIS EVENING AND OVERNIGHT EAST OF HWY 83 COULD CAUSE SOME BLOWING AND DRIFTING WITH REDUCED VISIBILITIES...ESPECIALLY EAST OF VALENTINE TO BREWSTER. THEREFORE...HAVE ISSUED A WINTER WEATHER ADVISORY IN EFFECT TONIGHT FOR KEYA PAHA...BOYD...ROCK...HOLT...GARFIELD AND WHEELER COUNTY. WILL NEED TO MONITOR DEVELOPMENT OF HEAVIER SNOW BANDS THIS AFTERNOON AND EVENING...WITH ADJACENT COUNTIES WESTWARD POSSIBLY SEEING HIGHER AMOUNTS AS WELL. MUCH COLDER AIR WILL BE DRAWN IN TONIGHT WITH LOWS 8 TO 12 ABOVE ACROSS NCTRL NEBR...15 TO 20 SWRN NEBR. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 357 AM CST SAT JAN 31 2015 FORECAST CONCERNS FOR THE FIRST PORTION OF THE PERIOD LIE WITH EXITING SNOW CHANCES ON SUNDAY AND TEMPERATURES IN THE WAKE OF THE SYSTEM FOR SUNDAY AND MONDAY. THE REMAINDER OF THE FORECAST PERIOD DEALS WITH FAIRLY QUICK NORTHWEST TO QUASI-ZONAL FLOW...LEADING TO DIFFICULTIES IN TIMING OF INDIVIDUAL SHORTWAVE TROUGHS INVOLVING TEMPERATURE VARIATIONS AND CHANCES FOR PRECIPITATION. CURRENTLY...THE HIGHEST CHANCES FOR PRECIPITATION WILL COME TUESDAY NIGHT AND WEDNESDAY. THE MODELS ARE IN DECENT AGREEMENT THROUGH THE PERIOD WITH THE GENERAL PATTERN...BUT DO HAVE SLIGHT DIFFERENCES IN TIMING PARTICULAR SYSTEMS...WHICH IS EXPECTED IN THIS FLOW REGIME. FOR SUNDAY AND INTO MONDAY...THE SYSTEM IMPACTING THE AREA TODAY WILL BE EXITING THE REGION AS THE UPPER LEVEL TROUGH PUSHES INTO THE MIDDLE MISSISSIPPI RIVER VALLEY REGION. THE COLD FRONT WILL BE WELL PAST THE AREA BY 12Z SUNDAY AND THE COLD AIR BEHIND IT WILL BE IN PLACE WITH 850MB TEMPERATURES FROM -10C TO-18C. MODELS ARE SHOWING GOOD SUBSIDENCE BEHIND THE SHORTWAVE AND WITH A TIGHT PRESSURE GRADIENT LOOKING FOR BREEZY WINDS...AND WITH THE BOUNDARY LAYER TO MIXING THROUGH THE DAY COULD GET GUSTS TO 30-35KTS. BY MID AFTERNOON ALL OF THE SNOW SHOULD BE OUT OF THE AREA. ONE OTHER MINOR CONCERN IS CHANCES FOR SOME LIGHT SNOW OVER THE EASTERN PANHANDLE. MODELS ARE INDICATING THERE WILL BE SOME WEAK TO MODERATE LIFT AS A SECONDARY PV ANOMALY MOVES SOUTH ACROSS THE AREA. MOISTURE WILL BE WANING THROUGH THE MORNING BUT COULD GET ENOUGH LIFT...ESPECIALLY OVER THE HIGHER TERRAIN TO INDUCE SOME LIGHT SNOW. AS FOR TEMPERATURES...WITH THE COLD AIRMASS EXPECTED LOOKING AT BELOW NORMAL TEMPERATURES. THE NORTHEAST HALF OF THE FORECAST AREA WILL SEE CLOUDS HANG ON THROUGH MUCH OF THE DAY WHICH WILL ALSO LIMIT THE TEMPERATURE RISE...WITH HIGHS IN THE LOW TO MID TEENS. TO THE SOUTHWEST...WHERE MORE SUNSHINE AND DEEPER MIXING IS EXPECTED...BELIEVE HIGHS IN THE MID TO UPPER 20S ARE APPROPRIATE. HIGH PRESSURE AT THE SURFACE SLIDES EAST ACROSS THE FORECAST AREA SUNDAY NIGHT...BUT BY 12Z MONDAY MORNING IS OFF TO THE EAST WITH SOUTHERLY RETURN FLOW TAKING OVER. THIS MAY LEAD TO A NON-DIURNAL TEMPERATURE CURVE OVERNIGHT AS TEMPERATURES WILL LIKELY DROP QUICKLY AS THE HIGH MOVES OVERHEAD WITH CLEAR SKIES AND LIGHT WINDS. ON MONDAY...THE MODELS ARE SHOWING A WEAK SHORTWAVE TROUGH MOVING ACROSS THE DAKOTAS AND NORTHEAST NEBRASKA IN THE NORTHWEST FLOW. THIS SYSTEM WILL BRING A WARM FRONT ACROSS THE AREA...WHILE THE MAJORITY OF THE MODELS ARE KEEPING ANY CHANCES FOR PRECIPITATION TO THE NORTHEAST OF THE AREA. KEPT THE FORECAST DRY BUT MAY NEED TO WATCH HOW THIS SYSTEM PROGRESSES OVER THE WEEKEND AS EVEN A SLIGHTLY MORE AMPLIFIED SYSTEM WOULD LIKELY BRING CHANCES FOR PRECIPITATION TO PORTIONS OF THE AREA. TEMPERATURES WILL BE A BIT WARMER FOR MONDAY AND TUESDAY WITH TUESDAY LOOKING TO BE WELL ABOVE NORMAL FOR PORTIONS OF THE FORECAST AREA. THIS WILL OCCUR AHEAD OF THE NEXT SYSTEM THAT WILL MOVE ACROSS THE REGION. THE MODELS ARE IN GOOD AGREEMENT WITH AN UPPER LEVEL SYSTEM COMING OUT OF NORTHWEST CANADA AND DROPPING THROUGH THE NORTHERN PLAINS LATER TUESDAY AND WEDNESDAY. THE COLD FRONT IS CURRENTLY TIMED TO PUSH THROUGH THE FORECAST AREA TUESDAY AFTERNOON. AHEAD OF THE FRONT...TEMPERATURES SHOULD RISE SIGNIFICANTLY...WITH UPPER 50S AND 60S POSSIBLE. ACROSS THE NORTH...WHERE THE COLDER AIR MOVES IN EARLIER...HIGHS MAY BE LIMITED TO 40S...WITH STEADY OR FALLING TEMPERATURES THROUGH THE AFTERNOON. SNOW CHANCES WILL COME BEHIND THE PASSAGE OF THE FRONT AS MOISTURE AND LIFT WILL BE LACKING IMMEDIATELY FOLLOWING. THIS HAS MUCH TO DO WITH THE UPPER JET...AS IT IS BASICALLY NON-EXISTENT OVER THE REGION UNTIL TUESDAY NIGHT AND WEDNESDAY. THE FORECAST WILL CONTINUE CHANCES FOR SNOW FOR TUESDAY NIGHT AND WEDNESDAY...HOWEVER ANY AMOUNTS ARE UNCERTAIN AT THIS TIME. COLDER TEMPERATURES ARE EXPECTED WITH THIS SYSTEM...BUT THE MODELS ARE IN GOOD AGREEMENT WITH BUILDING A RIDGE IN OVER THE ROCKIES AND PLAINS BY THE WEEKEND SO IF THE TREND CONTINUES...NEAR OR ABOVE NORMAL TEMPERATURES WOULD BE EXPECTED INTO NEXT WEEKEND. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1130 AM CST SAT JAN 31 2015 COMPLEX AVIATION WEATHER THE NEXT 24 HOURS. A LOW PRESSURE SYSTEM WILL MOVE ACROSS THE PLAINS WITH WIDESPREAD IFR CONDITIONS. PLENTIFUL LOW LEVEL MOISTURE WILL RESULT IN MOST AREAS SEEING IFR CLOUDS INTO TONIGHT...THEN LIFTING OVERNIGHT INTO TOMORROW MORNING TO MVFR. ALSO EXPECT SNOW TO DEVELOP AND REDUCE VISIBILITIES TO 3 MILES OR LESS AT TIMES. IN ADDITION TO THE SNOW WILL BE GUSTY NORTHERLY WINDS /GUSTS 20 TO 30 KTS/ DEVELOPING LATE TONIGHT INTO THE MORNING HOURS. THIS COULD RESULT IN LOCAL AREAS OF BLOWING SNOW...HOWEVER UNCERTAIN ABOUT SNOW TOTALS AT THE TERMINALS RESULTED IN NO BLSN IN THE TAF AT THIS TIME. && .LBF WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 3 PM CST /2 PM MST/ THIS AFTERNOON TO 6 AM CST /5 AM MST/ SUNDAY FOR NEZ005>010-023>029-094. && $$ UPDATE...MASEK SYNOPSIS...ROBERG SHORT TERM...ROBERG LONG TERM...BROOKS AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS OMAHA/VALLEY NE
1121 PM CST FRI JAN 30 2015 .UPDATE... ISSUED AT 907 PM CST FRI JAN 30 2015 THE OVERALL TREND OF THE FORECAST REMAINS ON TRACK WITH PRECIPITATION SPREADING NORTHEAST OUT OF CENTRAL KANSAS...THEN DEVELOPING NORTH TOWARD THE NE/SD BORDER REGION. BELIEVE PRECIP TYPE WILL BE THE ISSUE AND POSSIBLE CHANGEOVER TIME WHICH COMPLICATES THE FORECAST. 00Z NAM REMAINS VERY AGGRESSIVE WITH PRECIP DEVELOPMENT WITH 0.88 INCHES OF QPF AT KOMA THROUGH 48 HOURS. BUFKIT SOUNDINGS SUGGEST A FAIRLY RAPID CHANGEOVER TO SNOW WITH STRONG DYNAMICAL COOLING TAKING PLACE ACROSS THE REGION...WITH ABOUT 4 G/KG OF SPECIFIC HUMIDITY NOTED ON THE 290K ISENTROPIC SURFACE SO THERE IS PLENTY OF MOISTURE TO WORK WITH. INDEED...00Z SUBJECTIVE UPPER AIR ANALYSIS INDICATES FAIRLY DEEP AND SATURATED MOISTURE STREAMING NORTHWARD WITH ABOUT 0.6 TO 0.8 INCHES OF PW...WHICH IS IN THE 97.5-99 NAEFS PW CLIMATOLOGICAL PERCENTILE ALONG AND SOUTH OF I80. AN INITIAL CONCERN IS THAT PRECIP COULD POTENTIALLY CHANGE OVER TO ALL SNOW EARLIER THAN FORECAST RESULTING IN HIGHER SNOWFALL TOTALS. THE SECOND CONCERN IS THE RATHER DEEP SATURATION THAT IS PROGGED TO OVERSPREAD THE REGION RESULTING IN HIGHER QPF THAN FORECAST. MODEL SUITES ARE ALL GENERATING 0.7 TO 0.9 INCHES OF QPF AND OUR FORECAST REMAINS BELOW THAT BY ABOUT ONE QUARTER INCH. ONE MITIGATING FACTOR IS THE SREF PROBABILITY OF ACCUMULATION ON ROADS PRODUCT REMAINS LOW MUCH OF THE DAY SATURDAY...HOLDING OFF UNTIL WELL AFTER DARK BEFORE ROADWAYS BECOME SIGNIFICANTLY IMPACTED. THAT DOESN`T MEAN WOULD WOULDN`T STILL BE ABLE TO ACCUMULATE SNOWFALL ON GRASSY SURFACES THOUGH. WILL WAIT FOR GFS...SREF...HIRES AND ECMWF MODELS BEFORE MAKING MAJOR CHANGES...BUT INITIAL THOUGHTS ARE THAT QPF/SNOW AMOUNTS MAY NEED TO BE RAISED. EARLY IN THE EVENT...WINDS WILL ALSO REMAIN GENERALLY LIGHT LESS THAN 10 MPH WHICH WILL HELP QUITE A BIT. CURRENT STORM TOTAL SNOWFALL FORECAST RANGES FROM 1 TO 4 INCHES ACROSS THE REGION...BUT AGAIN...WILL WAIT FOR COMPLETE MODEL SUITES TO MAKE ANY UPWARD ADJUSTMENTS. && .SHORT TERM...(TONIGHT THROUGH MONDAY) ISSUED AT 310 PM CST FRI JAN 30 2015 PCPN TYPE AND PCPN AMOUNTS WILL BE THE MAIN CONCERN IN THIS PERIOD... ESPECIALLY FROM LATE TONIGHT INTO SATURDAY EVENING. PCPN SHOULD TURN TO MOSTLY SNOW BY LATE SATURDAY NIGHT ALL AREAS. WATER VAPOR LOOP AND LATEST RAP MODEL INITIALIZATIONS SHOWED A CLOSED LOW OVER THE CALIFORNIA/ARIZONA BORDER REGION EARLY THIS AFTN. THIS WILL DROP SOUTHWARD INTO MEXICO THROUGH SUNDAY. SOME SHORTWAVE ENERGY WILL MOVE NORTHEAST OUT OF THIS TROUGH THOUGH AND MOVE UP INTO THE CENTRAL PLAINS LATER TONIGHT AND SATURDAY. SURFACE ANALYSIS EARLY THIS AFTERNOON SHOWED MODEST SOUTH/SOUTHWEST WINDS SPREADING ACROSS OUR AREA. CLOUDS WILL THICKEN AND LOWER...WITH LIGHT PCPN PROBABLY MOVING INTO OUR SOUTHERN COUNTIES BEFORE 12Z. HAVE LOWS FORECAST IN THE UPPER 20S NORTH AND LOWER 30S SOUTH. THE PCPN TYPE MAY BE A MIX LATER TONIGHT INTO SATURDAY. DID MAKE SOME MODIFICATIONS TO SNOW AMOUNTS...MAINLY FOR SATURDAY NIGHT INTO SUNDAY MORNING. ON SATURDAY...IT APPEARS THAT IF WE GET ANY ACCUMULATIONS...THEY WOULD BE LIGHT AND MAINLY ON GRASSY AREAS FOR OUR SOUTHERN ZONES. FARTHER NORTH...PCPN CHANCES WILL BE INCREASING IN THE AFTERNOON BUT AMOUNTS WOULD BE LIGHTER. THE NAM FORECAST SOUNDINGS STILL APPEARED TOO COLD...AND WENT CLOSER TO A BLEND OF SOME OF THE OTHER MODELS...ESPECIALLY THE SREF. NORTH WINDS WILL SPREAD ACROSS THE AREA SATURDAY NIGHT...AND AS THE COLUMN COOLS...PCPN WILL CHANGE TO MOSTLY SNOW AND WILL START TO ACCUMULATE. A SEPARATE SYSTEM WILL DROP QUICKLY SOUTHEAST IN THE NORTHWEST FLOW SATURDAY NIGHT...PROVIDING GOOD LIFT IN A FAVORABLE ENVIRONMENT FOR SNOW FROM THE NORTHERN PARTS OF NORTHEAST NEBRASKA INTO WEST CENTRAL IOWA. INCREASED SNOW AMOUNTS FOR AREAS ALONG AND NORTH OF HIGHWAY 20. IT APPEARS ANOTHER LOBE OF LIFT WILL DROP DOWN OVER PARTS OF THE AREA SUNDAY AFTERNOON...SO KEPT SOME MENTION OF LIGHT SNOW GOING UNTIL SUNDAY NIGHT. SUNDAY NIGHT IS EXPECTED TO BE COLD WITH DECREASING CLOUDS AND DECREASING WINDS. LOWS SHOULD DROP TO THE SINGLE DIGITS AND WE MAY SEE SOME BELOW ZERO NUMBERS FROM HARTINGTON AND WAYNE TOWARD TEKAMAH AND HARLAN. FAST NORTHWEST FLOW IN THE MID LEVELS WILL BE IN PLACE FOR MONDAY AND IT DOES APPEAR THAT A SHORTWAVE TROUGH COULD MOVE THROUGH OUR AREA. MODELS...ESPECIALLY THE 12Z GFS...BRING SOME LIGHT SNOW IN FOR MONDAY AFTERNOON. COULD NOT ARGUE WITH THAT TOO MUCH SO WENT WITH A SLIGHT CHANCE OF LIGHT SNOW FOR NOW AND WILL FINE TUNE THAT LATER. MEASURABLE LIGHT AMOUNTS SEEM POSSIBLE...ESPECIALLY IN WESTERN IOWA MONDAY. HIGHS MONDAY WILL BE MOSTLY 20S. .LONG TERM...(MONDAY NIGHT THROUGH FRIDAY) ISSUED AT 310 PM CST FRI JAN 30 2015 SOME MILDER AIR WILL SPREAD IN BRIEFLY FOR TUESDAY...WITH HIGHS REACHING THE UPPER 30S AND LOWER 40S. DID NOT WANT TO GET TOO OPTIMISTIC AT THIS POINT FOR HIGHS. ANOTHER SURGE OF COLDER AIR WILL DROP DOWN INTO THE AREA BY TUESDAY NIGHT. SOME LIGHT SNOW SEEMS POSSIBLE BASED ON THE PATTERN...PLUS BOTH THE 12Z GFS AND ECMWF SHOW A BIT OF SNOW. TEMPERATURES WEDNESDAY AND THURSDAY WILL BE BELOW NORMAL...THEN CLOSER TO NORMAL BY FRIDAY AS SOUTH OR SOUTHWEST WINDS INCREASE. && .AVIATION...(06Z TAFS FOR KOFK...KLNK AND KOMA.) ISSUED AT 1119 PM CST FRI JAN 30 2015 VFR INITIALLY. RAIN AND MVFR CEILINGS DEVELOP AT KLNK BY 10-14Z...KOMA 14-18Z AND KOFK 15-19Z. SHOULD START TO SEE SNOW MIX WITH THE RAIN BY 21-00Z...CHANGING OVER TO ALL SNOW. WINDS SOUTHERLY INITIALLY...THEN BACKING BECOMING SOUTHEAST...EAST...AND EVENTUALLY NORTHEAST AND SUBSTANTIALLY INCREASING AT KOFK TOWARD THE END OF THE PERIOD...AND AT KLNK/KOMA JUST BEYOND THE END OF THE TAF PERIOD. && .OAX WATCHES/WARNINGS/ADVISORIES... NE...NONE. IA...NONE. && $$ UPDATE...DEWALD SHORT TERM...KERN/MILLER LONG TERM...MILLER AVIATION...DEWALD
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
850 PM EST SUN FEB 1 2015 .SYNOPSIS... A MAJOR WINTER STORM WILL IMPACT THE REGION OVERNIGHT AND MONDAY. UP TO A FOOT OF SNOW IS EXPECTED IN CENTRAL NEW YORK WITH 5 TO 8 INCHES IN NORTHEAST PENNSYLVANIA. ONCE THIS STORM MOVES OFF THE COAST MONDAY NIGHT...BITTERLY COLD AIR WILL SETTLE INTO THE REGION AGAIN...LASTING THROUGH MOST OF THE WEEK. && .NEAR TERM /THROUGH MONDAY/... RADAR SHOWS SNOW SHIELD CONTINUING TO MOVE NORTHEAST ACRS C NY AND NE PA AS WAA OR ISENTROPIC LIFT CONTINUES TO INCREASE OVER THE REGION. THE UPPER LEVEL JET STRUCTURE WAS LEADING TO A RIGHT ENTRANCE REGION JET CIRCULATION OVER NY AND PA WITH A LEFT EXIT REGION MOVING NORTH TWD THE REGION FROM THE SOUTHERN STREAM. THE AGEO CIRC THAT RESPONDS TO THIS JET CONFIGURATION PRESSES THE LOW-LEVEL ISENTROPES FARTHER SOUTH AS THE LEFT EXIT LEADS TO SIGNIFICANT FLOW UP THE ISENTROPES. ADDITIONALLY THE UPPER LEVEL SHORT WAVE THAT WAS LEADING TO THESE UPPER JET STRUCTURES WAS MOVING EASTWARD AND WILL REACH OH AND THE ERN LAKES BY 12Z AND CNTRL NY BY 18Z AND WRN NEW ENGLAND BY 00Z. THIS UPR LVL WAVE WILL ALSO BE LIFTING THE ISENTROPES AS THE WAVE MOVES E...LEADING TO IMPRESSIVE LIFTING WITH THIS SYSTEM OVER C NY AND NE PA. MODEL RADARS INDICATE THAT THE HEAVIEST SNOW WILL OCCUR BETWEEN ROUGHLY 6Z-9Z AND 12-15Z FROM SW TO NE. BELIEVE UP TO 2 INCHES PER HOUR IS MOST LIKELY ACRS NC NY WHERE SNOW TO LIQUID RATIOS WILL BE HIGHER. BELIEVE HEAVIEST SNOW WILL BE ACRS NC NY WHERE 10-14 INCHES WILL LIKELY OCCUR. FARTHER S...ACRS MUCH OF THE FINGER LAKES AND SC NY/NRN TIER OF ERN PA...LOOKS LIKE 8-12 INCHES. FARTHER S...EXPECT 5 TO 8 INCHES AT BEST. WARMER AIR WILL MAKE IT TO THE NRN TIER OF ERN PA AS PER 18Z RUNS OF THE NAM...GFS...RGEM AND THE 2.5 KM HI RES CANADIAN MODELS AND THE LATEST HRRR AND RAP MODELS BY 12Z TO 15Z MON. I USED ALL THIS NEW GUIDC TO ADJUST THE ZR AND IP FARTHER N INTO THE NRN TIER OF ERN PA MON AM. MORE SLEET AND FREEZING RAIN IN THE AVP AREA TO POCONOS WILL CUT SNOW AMNTS DOWN. FOR NOW HAVE 5 TO 8 INCHES WITH ARND .1 TO .2 INCHES OF ICE. FOR MONDAY AFTERNOON...NORTHWEST WINDS PICK UP AND GUST TO 25 MPH...ESP IN C NY AND FAR NRN PA...SO ADDED BLOWING AND DRIFTING SNOW MONDAY AFTERNOON TO WINTER STORM WARNING IN THESE AREAS. WILL ALSO ADD TO AN UPDATED DSS BRIEFING. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... ARCTIC ARE WILL SPILL BACK DOWN FROM CANADA ON THE BACK SIDE OF THE CYCLONE. APPARENT TEMPERATURES FOR THE NORTH AND EAST RANGE FROM -10F TO -18F OVERNIGHT, BORDERLINE FOR A WIND CHILL ADVISORY. WE WON`T CONSIDER AN ADVISORY AT THIS POINT, AS WE DON`T WISH TO DISTRACT FROM THE CURRENT STORM SCENARIO. AFTER A DRY, COLD DAY TUESDAY...INCLUDING SOME WEAK LAKE ACTIVITY TO THE NORTHWEST...ANOTHER WAVE WILL DIP DOWN ACROSS NY LATE TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL HAVE LIMITED MOISTURE BUT SHOULD STILL PRODUCE 2 TO 3 INCHES OF NEW SNOW. THE REAL IMPACT OF THE WAVE WILL BE TO USHER IN ANOTHER ARCTIC BLAST FOR THURSDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... WIDESPREAD IFR VSBYS DEVELOPING ACROSS THE TERMINALS THIS EVENING. FOR THE SOUTHERN TERMINALS OF KITH/KELM/KBGM AND KAVP, GENERALLY 1 TO 2SM THROUGH 03Z. BETWEEN 03Z AND 06Z VSBYS WILL BEGIN TO DROP UNDER 1SM, WITH SOLID VSBYS UNDER 1SM FROM 06Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS LATE TONIGHT, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MID MONDAY MORNING BEFORE TAPERING OFF. UP NORTH AT KSYR AND KRME, MUCH LATER ARRIVAL OF SNOWFALL DUE TO DRY AIR. IFR VSBYS HERE BETWEEN 02Z AND 06Z, WITH THE LOWER VSBYS UNDER 1SM NOT LIKELY UNTIL AFTER 07Z OR 08Z. HERE LOWER VSBYS WILL IMPROVE TOWARD MID MONDAY MORNING ON THE BACKSIDE OF THE STORM, BEFORE MVFR CIGS/VSBYS MONDAY AFTERNOON DUE TO WRAP AROUND SNOW SHOWERS. EAST WINDS 5 T0 10 KTS TONIGHT. WINDS SHIFTING INTO THE NORTHWEST BY MONDAY AFTERNOON, SUSTAINED 10-12 KTS BUT GUSTS TO 20-25 KTS POSSIBLE. OUTLOOK... MON NGT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR PAZ038>040-043- 044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR NYZ009-015>018- 022>025-036-037-044>046-055>057-062. && $$ SYNOPSIS...DJN NEAR TERM...DJN SHORT TERM...DJP LONG TERM...DJP AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
738 PM EST SUN FEB 1 2015 .SYNOPSIS... A SIGNIFICANT WINTER STORM WILL IMPACT THE REGION OVERNIGHT AND MONDAY. ONCE THIS STORM MOVES OFF THE COAST MONDAY NIGHT...BITTERLY COLD WEATHER WILL SET IN AGAIN...LASTING THROUGH TUESDAY. && .NEAR TERM /THROUGH MONDAY/... 6 PM UPDATE...DID AN UPDATE OF THE WINTER WEATHER MESSAGE ISSUED FOR OUR WINTER STORM WARNINGS TO REFINE TIMING OF THE BEGINNING OF THE WINTER STORM. MADE SOME MINOR ADJUSTMENTS TO THE TIMING AND INTENSITY OF SNOW SHIELD AS IT CONTINUES TO PUSH NORTH AND EAST. LOOKING AT THE LATEST GUIDC...WE MAY HAVE TO ADJUST SNOW AMOUNTS UP ACROSS SYR-UCA-RME AREAS AND LOWER AMNTS IN NE PA. HEAVIER SNOW MAY REACH FARTHER NORTH THAN WE HAVE ADVERTISED AT THIS POINT. THE ZR/IP LINE CUD MAKE A RUN FOR THE NY BORDER LATE TONIGHT/EARLY MONDAY. WE WILL CONTINUE TO MONITOR LATEST GUIDC AND MAKE CHANGES IF ENUF SCIENTIFIC EVIDENCE HOLDS. ANOTHER CONCERN IS THAT HRRR IS SLOWER THAN OUR LOCAL WRF...RAP...NAM12 AND WRF_NMM AND WRF_ARW IN BRINGING IN THE HEAVIER SNOW LATER TONIGHT. WE WILL AGAIN MONITOR THE SNOW SHIELD AS IT PROGRESSES NEXT FEW HOURS. DYNAMICS FOR THE EVENING AND OVERNIGHT ARE INCREASING WAA OR ISENTROPIC LIFT AHEAD OF AN UPPER LEVEL SHORT WAVE TROF WHICH MAKES IT TO OH TO THE ERN LAKES BY 12Z. HENCE WE WILL SEE LIFTG AS AIR FLOWS UP THE ISENTROPES IN ADDITION TO THE ISENTROPES BODILY RISING IN ADVANCE OF THE SHRT WAVE TROF. HENCE THE HEAVIEST SNOW WILL FALL BETWEEN 6Z AND 12Z MOST AREAS. IN NE PA...A SLIGHTLY ABOVE FREEZING LAYER LIKELY WILL SNEAK NORTH AS PER NAM...GFS AND SREF MODEL SOUNDINGS AND REACH INTO NE PA BETWEEN 9Z AND 12-14Z. HOW FAR N THIS MAKES IT IS UNCERTAIN...BUT MODELS INDICATE AT LEAST KAVP...POSSIBLY THE PA/NY BORDER BY 12-14Z. AGAIN WILL MONITOR AND WITH 10 PM UPDATE MIGHT HAVE TO LOWER AMNTS IN NE PA. NC NY MAY SEE THE MOISTURE FROM STRG THERMAL AND MOISTURE ADVTNS REACH UP THERE AND WITH HIGHER SNOW RATIOS AMNTS CUD BE HIGHER THAN WHAT WE HAVE. GRIDS UPDATED. LEFT SNOW AMOUNTS ALONE AS WAITING FOR MORE GUIDC AND THE CHARACTER OF THE EVOLVING RADAR TRENDS VS THE HI RES MODEL RADAR TRENDS. PREVIOUS DSCN BELOW... 3 PM SUN UPDATE... THE LEADING EDGE OF THE STEADIER -SN EXTENDS FROM OUR WRN FINGER LAKES/CNTRL SRN TIER ZNS...DOWN INTO PTNS OF NE PA ATTM. IT WILL CONTINUE TO EXPAND NEWD THROUGH THIS EVE...REACHING THE MOHAWK VLY AND SRN TUG HILL RGNS BY ARND 02Z. IT`S PSBL THIS COULD HAPPEN A BIT QUICKER...AS EXISTING LOW-LVL MOISTURE ACRS CNY/NE PA COULD AID IN THE TOP-DOWN MOISTENING PROCESS. THE MAIN EVENT STILL LOOKS TO BE OVERNIGHT AND MON MRNG (ROUGHLY 03-15Z). IT IS IN THIS TIME FRAME THAT EXCELLENT COUPLED JET STRUCTURE DYNAMICS TAKE HOLD...TO HELP TRANSPORT A MOISTURE-LADEN AMS INTO THE NERN U.S. (BLENDED TPW IMAGERY SHOWING THE SOURCE NICELY OVER THE WRN GOMEX/LWR MS/OH VLYS)...AND SET THE STAGE FOR STG FORCED ASCENT (EXCELLENT LOW-LVL SPEED CONVERGENCE AND A TIGHT THERMAL GRADIENT LEADING TO PRONOUNCED FGEN OVER A DEEP LYR). WHERE PTYP REMAINS ALL SNOW...RATES OF 1-2"/HR COULD OCCUR FOR A SUBSET OF THIS TIME FRAME (MAINLY 06-12Z). THE MAIN COMPLICATING FACTOR REMAINS PTYP. THE 12Z GFS IN PARTICULAR MADE A SLGT NWD JOG AGN IN THE CYCLONE TRACK...WITH THE LEADING EDGE OF THE WARM NOSE ALOFT (850-875 MB) MAKING A RUN AT THE PA/NY BORDER BY 12Z. SREF THERMAL PROFILES GIVE SOME CREDENCE TO THIS SCENARIO. ALTHOUGH THE LATEST NAM/RGNL GEM/EC RUNS ARE SOMEWHAT COLDER...THE AMPLIFIED NATURE OF THE S/WV SEEN IN WATER VAPOR IMAGERY ATTM OVER THE MIDWEST CERTAINLY OPENS THE DOOR TO THE PSBLTY OF A MORE NWD STORM TRACK/MORE EXPANSIVE SHIELD OF MIXED PCPN EARLY MON. OUT OF RESPECT TO THE GFS...WHICH HAS BEEN CONSISTENTLY SHOWING THIS TREND FOR SVRL RUNS NOW...WE DID NUDGE SNOWFALL AMTS DOWN SLIGHTLY IN OUR FAR SRN ZNS...AND CORRESPONDINGLY UPWARD IN OUR NRN TIER OF ZNS. OVERALL...THIS DIDN`T CHG TOTAL ACCUMS APPRECIABLY. EVEN IF THE SOMEWHAT WARMER SCENARIO VERIFIES...WE STILL FEEL THAT THERMAL/MOISTURE ADVECTION WILL BE STG ENUF OVERNIGHT TO PRODUCE A QUICK 4-8" OF SNOW BEFORE DAYBREAK ACRS MUCH OF THE CWA. DURG THE DAY MON...AS THE SFC LOW TRANSLATES TWDS THE NJ COAST/SRN LONG ISLAND...COLDER AIR WILL SPREAD SEWD THROUGH THE RGN BY AFTN. CONSEQUENTLY...ANY AREAS OF MIXED PCPN SHOULD BE BACK OVER TO SNOW BY 15-18Z. AT THE SAME TIME...MOST OF THE MODELS ARE SHOWING A 3-6 HR WINDOW FOR DEFORMATION TYPE BANDING (MAINLY FROM ABT 15-21Z)...WITH THE MID-LVL DRY SLOT CLOSE ENUF FOR REDUCED STABILITY ALOFT...AND AN INCREASING 700-500 MB FGEN BAND SHIFTING ACRS CNY/NE PA. THE BEST CHC FOR MORE PERSISTENT SNOW BANDING (ADDTNL ACCUMS) SHOULD BE NEAR AND E OF THE I-81 CORRIDOR. WHEN ALL IS SAID AND DONE...WE STILL EXPECT STORM TOTAL SNOWFALL OF 6-10" IN OUR FAR NRN AND SRN ZNS...WITH A SLIGHTLY HVYR STRIPE OF 8-12" IN THE MIDDLE (LOCALLY HIER AMTS (UP TO ARND 14") MOST LIKELY TWDS CHENANGO/OTSEGO/DELAWARE CNTYS). AS ALLUDED TO ABV...TEMPS WILL BE FALLING SHARPLY MON AFTN...WITH BITTERLY COLD WIND CHILLS BCMG MORE OF AN ISSUE WITH TIME. MORE ON THIS IN THE FOLLOWING SXN. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... ARCTIC ARE WILL SPILL BACK DOWN FROM CANADA ON THE BACK SIDE OF THE CYCLONE. APPARENT TEMPERATURES FOR THE NORTH AND EAST RANGE FROM -10F TO -18F OVERNIGHT, BORDERLINE FOR A WIND CHILL ADVISORY. WE WON`T CONSIDER AN ADVISORY AT THIS POINT, AS WE DON`T WISH TO DISTRACT FROM THE CURRENT STORM SCENARIO. AFTER A DRY, COLD DAY TUESDAY...INCLUDING SOME WEAK LAKE ACTIVITY TO THE NORTHWEST...ANOTHER WAVE WILL DIP DOWN ACROSS NY LATE TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL HAVE LIMITED MOISTURE BUT SHOULD STILL PRODUCE 2 TO 3 INCHES OF NEW SNOW. THE REAL IMPACT OF THE WAVE WILL BE TO USHER IN ANOTHER ARCTIC BLAST FOR THURSDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /01Z MONDAY THROUGH FRIDAY/... WIDESPREAD IFR VSBYS DEVELOPING ACROSS THE TERMINALS THIS EVENING. FOR THE SOUTHERN TERMINALS OF KITH/KELM/KBGM AND KAVP, GENERALLY 1 TO 2SM THROUGH 03Z. BETWEEN 03Z AND 06Z VSBYS WILL BEGIN TO DROP UNDER 1SM, WITH SOLID VSBYS UNDER 1SM FROM 06Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS LATE TONIGHT, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MID MONDAY MORNING BEFORE TAPERING OFF. UP NORTH AT KSYR AND KRME, MUCH LATER ARRIVAL OF SNOWFALL DUE TO DRY AIR. IFR VSBYS HERE BETWEEN 02Z AND 06Z, WITH THE LOWER VSBYS UNDER 1SM NOT LIKELY UNTIL AFTER 07Z OR 08Z. HERE LOWER VSBYS WILL IMPROVE TOWARD MID MONDAY MORNING ON THE BACKSIDE OF THE STORM, BEFORE MVFR CIGS/VSBYS MONDAY AFTERNOON DUE TO WRAP AROUND SNOW SHOWERS. EAST WINDS 5 T0 10 KTS TONIGHT. WINDS SHIFTING INTO THE NORTHWEST BY MONDAY AFTERNOON, SUSTAINED 10-12 KTS BUT GUSTS TO 20-25 KTS POSSIBLE. OUTLOOK... MON NGT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR PAZ038>040-043- 044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR NYZ009-015>018- 022>025-036-037-044>046-055>057-062. && $$ SYNOPSIS...MLJ NEAR TERM...DJN/MLJ SHORT TERM...DJP LONG TERM...DJP AVIATION...HEDEN
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
631 PM EST SUN FEB 1 2015 .SYNOPSIS... A SIGNIFICANT WINTER STORM WILL IMPACT THE REGION OVERNIGHT AND MONDAY. ONCE THIS STORM MOVES OFF THE COAST MONDAY NIGHT...BITTERLY COLD WEATHER WILL SET IN AGAIN...LASTING THROUGH TUESDAY. && .NEAR TERM /THROUGH MONDAY/... 6 PM UPDATE...DID AN UPDATE OF THE WINTER WEATHER MESSAGE ISSUED FOR OUR WINTER STORM WARNINGS TO REFINE TIMING OF THE BEGINNING OF THE WINTER STORM. MADE SOME MINOR ADJUSTMENTS TO THE TIMING AND INTENSITY OF SNOW SHIELD AS IT CONTINUES TO PUSH NORTH AND EAST. LOOKING AT THE LATEST GUIDC...WE MAY HAVE TO ADJUST SNOW AMOUNTS UP ACROSS SYR-UCA-RME AREAS AND LOWER AMNTS IN NE PA. HEAVIER SNOW MAY REACH FARTHER NORTH THAN WE HAVE ADVERTISED AT THIS POINT. THE ZR/IP LINE CUD MAKE A RUN FOR THE NY BORDER LATE TONIGHT/EARLY MONDAY. WE WILL CONTINUE TO MONITOR LATEST GUIDC AND MAKE CHANGES IF ENUF SCIENTIFIC EVIDENCE HOLDS. ANOTHER CONCERN IS THAT HRRR IS SLOWER THAN OUR LOCAL WRF...RAP...NAM12 AND WRF_NMM AND WRF_ARW IN BRINGING IN THE HEAVIER SNOW LATER TONIGHT. WE WILL AGAIN MONITOR THE SNOW SHIELD AS IT PROGRESSES NEXT FEW HOURS. DYNAMICS FOR THE EVENING AND OVERNIGHT ARE INCREASING WAA OR ISENTROPIC LIFT AHEAD OF AN UPPER LEVEL SHORT WAVE TROF WHICH MAKES IT TO OH TO THE ERN LAKES BY 12Z. HENCE WE WILL SEE LIFTG AS AIR FLOWS UP THE ISENTROPES IN ADDITION TO THE ISENTROPES BODILY RISING IN ADVANCE OF THE SHRT WAVE TROF. HENCE THE HEAVIEST SNOW WILL FALL BETWEEN 6Z AND 12Z MOST AREAS. IN NE PA...A SLIGHTLY ABOVE FREEZING LAYER LIKELY WILL SNEAK NORTH AS PER NAM...GFS AND SREF MODEL SOUNDINGS AND REACH INTO NE PA BETWEEN 9Z AND 12-14Z. HOW FAR N THIS MAKES IT IS UNCERTAIN...BUT MODELS INDICATE AT LEAST KAVP...POSSIBLY THE PA/NY BORDER BY 12-14Z. AGAIN WILL MONITOR AND WITH 10 PM UPDATE MIGHT HAVE TO LOWER AMNTS IN NE PA. NC NY MAY SEE THE MOISTURE FROM STRG THERMAL AND MOISTURE ADVTNS REACH UP THERE AND WITH HIGHER SNOW RATIOS AMNTS CUD BE HIGHER THAN WHAT WE HAVE. GRIDS UPDATED. LEFT SNOW AMOUNTS ALONE AS WAITING FOR MORE GUIDC AND THE CHARACTER OF THE EVOLVING RADAR TRENDS VS THE HI RES MODEL RADAR TRENDS. PREVIOUS DSCN BELOW... 3 PM SUN UPDATE... THE LEADING EDGE OF THE STEADIER -SN EXTENDS FROM OUR WRN FINGER LAKES/CNTRL SRN TIER ZNS...DOWN INTO PTNS OF NE PA ATTM. IT WILL CONTINUE TO EXPAND NEWD THROUGH THIS EVE...REACHING THE MOHAWK VLY AND SRN TUG HILL RGNS BY ARND 02Z. IT`S PSBL THIS COULD HAPPEN A BIT QUICKER...AS EXISTING LOW-LVL MOISTURE ACRS CNY/NE PA COULD AID IN THE TOP-DOWN MOISTENING PROCESS. THE MAIN EVENT STILL LOOKS TO BE OVERNIGHT AND MON MRNG (ROUGHLY 03-15Z). IT IS IN THIS TIME FRAME THAT EXCELLENT COUPLED JET STRUCTURE DYNAMICS TAKE HOLD...TO HELP TRANSPORT A MOISTURE-LADEN AMS INTO THE NERN U.S. (BLENDED TPW IMAGERY SHOWING THE SOURCE NICELY OVER THE WRN GOMEX/LWR MS/OH VLYS)...AND SET THE STAGE FOR STG FORCED ASCENT (EXCELLENT LOW-LVL SPEED CONVERGENCE AND A TIGHT THERMAL GRADIENT LEADING TO PRONOUNCED FGEN OVER A DEEP LYR). WHERE PTYP REMAINS ALL SNOW...RATES OF 1-2"/HR COULD OCCUR FOR A SUBSET OF THIS TIME FRAME (MAINLY 06-12Z). THE MAIN COMPLICATING FACTOR REMAINS PTYP. THE 12Z GFS IN PARTICULAR MADE A SLGT NWD JOG AGN IN THE CYCLONE TRACK...WITH THE LEADING EDGE OF THE WARM NOSE ALOFT (850-875 MB) MAKING A RUN AT THE PA/NY BORDER BY 12Z. SREF THERMAL PROFILES GIVE SOME CREDENCE TO THIS SCENARIO. ALTHOUGH THE LATEST NAM/RGNL GEM/EC RUNS ARE SOMEWHAT COLDER...THE AMPLIFIED NATURE OF THE S/WV SEEN IN WATER VAPOR IMAGERY ATTM OVER THE MIDWEST CERTAINLY OPENS THE DOOR TO THE PSBLTY OF A MORE NWD STORM TRACK/MORE EXPANSIVE SHIELD OF MIXED PCPN EARLY MON. OUT OF RESPECT TO THE GFS...WHICH HAS BEEN CONSISTENTLY SHOWING THIS TREND FOR SVRL RUNS NOW...WE DID NUDGE SNOWFALL AMTS DOWN SLIGHTLY IN OUR FAR SRN ZNS...AND CORRESPONDINGLY UPWARD IN OUR NRN TIER OF ZNS. OVERALL...THIS DIDN`T CHG TOTAL ACCUMS APPRECIABLY. EVEN IF THE SOMEWHAT WARMER SCENARIO VERIFIES...WE STILL FEEL THAT THERMAL/MOISTURE ADVECTION WILL BE STG ENUF OVERNIGHT TO PRODUCE A QUICK 4-8" OF SNOW BEFORE DAYBREAK ACRS MUCH OF THE CWA. DURG THE DAY MON...AS THE SFC LOW TRANSLATES TWDS THE NJ COAST/SRN LONG ISLAND...COLDER AIR WILL SPREAD SEWD THROUGH THE RGN BY AFTN. CONSEQUENTLY...ANY AREAS OF MIXED PCPN SHOULD BE BACK OVER TO SNOW BY 15-18Z. AT THE SAME TIME...MOST OF THE MODELS ARE SHOWING A 3-6 HR WINDOW FOR DEFORMATION TYPE BANDING (MAINLY FROM ABT 15-21Z)...WITH THE MID-LVL DRY SLOT CLOSE ENUF FOR REDUCED STABILITY ALOFT...AND AN INCREASING 700-500 MB FGEN BAND SHIFTING ACRS CNY/NE PA. THE BEST CHC FOR MORE PERSISTENT SNOW BANDING (ADDTNL ACCUMS) SHOULD BE NEAR AND E OF THE I-81 CORRIDOR. WHEN ALL IS SAID AND DONE...WE STILL EXPECT STORM TOTAL SNOWFALL OF 6-10" IN OUR FAR NRN AND SRN ZNS...WITH A SLIGHTLY HVYR STRIPE OF 8-12" IN THE MIDDLE (LOCALLY HIER AMTS (UP TO ARND 14") MOST LIKELY TWDS CHENANGO/OTSEGO/DELAWARE CNTYS). AS ALLUDED TO ABV...TEMPS WILL BE FALLING SHARPLY MON AFTN...WITH BITTERLY COLD WIND CHILLS BCMG MORE OF AN ISSUE WITH TIME. MORE ON THIS IN THE FOLLOWING SXN. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY/... ARCTIC ARE WILL SPILL BACK DOWN FROM CANADA ON THE BACK SIDE OF THE CYCLONE. APPARENT TEMPERATURES FOR THE NORTH AND EAST RANGE FROM -10F TO -18F OVERNIGHT, BORDERLINE FOR A WIND CHILL ADVISORY. WE WON`T CONSIDER AN ADVISORY AT THIS POINT, AS WE DON`T WISH TO DISTRACT FROM THE CURRENT STORM SCENARIO. AFTER A DRY, COLD DAY TUESDAY...INCLUDING SOME WEAK LAKE ACTIVITY TO THE NORTHWEST...ANOTHER WAVE WILL DIP DOWN ACROSS NY LATE TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL HAVE LIMITED MOISTURE BUT SHOULD STILL PRODUCE 2 TO 3 INCHES OF NEW SNOW. THE REAL IMPACT OF THE WAVE WILL BE TO USHER IN ANOTHER ARCTIC BLAST FOR THURSDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... A POWERFUL STORM WILL SPREAD SNOW FROM SOUTHWEST TO NORTHEAST OVER THE NEXT SEVERAL HOURS. THE SNOW WILL ARRIVE IN AVP AND ELM BETWEEN 18Z AND 19Z, BGM AND ITH BETWEEN 20Z AND 22Z, AND RME AND SYR BETWEEN 01Z AND 03Z. THE SNOW WILL LOWER VISIBILITIES TO BETWEEN 1SM AND 2SM, WITH LOWER VISIBILITIES POSSIBLE OVERNIGHT AS THE SNOW INTENSIFIES. CEILINGS WILL LIKELY BEGIN AS MVFR AND TREND DOWNWARD TO IFR OVERNIGHT. A LONG PERIOD OF IFR CONDITIONS IS FORECAST BEFORE THE ENDS LATE MONDAY AFTERNOON. WINDS WILL SHIFT TO THE EAST AT 5 TO 10 KNOTS. OUTLOOK... MON...IFR RESTRICTIONS IN SNOW. MON NGT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR PAZ038>040-043- 044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR NYZ015>018- 022>025-036-037-044>046-055>057-062. WINTER STORM WARNING UNTIL 4 PM EST MONDAY FOR NYZ009. && $$ SYNOPSIS...MLJ NEAR TERM...DJN/MLJ SHORT TERM...DJP LONG TERM...DJP AVIATION...DJP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
251 AM EST SAT JAN 31 2015 .SYNOPSIS... VERY COLD AIR WILL CONTINUE TO POUR INTO THE REGION TONIGHT...WITH LAKE-EFFECT SNOW PERSISTING DOWNWIND FROM THE FINGER LAKES...AND BITTERLY COLD WIND CHILLS AREA-WIDE. COLD TEMPERATURES WILL LAST THROUGH THE UPCOMING WEEKEND...WITH ONLY A FEW FLURRIES FORESEEN FROM SATURDAY INTO EARLY SUNDAY. AN APPROACHING WINTER STORM COULD BEGIN TO IMPACT THE AREA BY LATE SUNDAY AFTERNOON OR SUNDAY EVENING...WITH ACCUMULATING SNOW POSSIBLE. && .NEAR TERM /THROUGH TODAY/... 945 PM UPDATE... LAKE EFFECT SNOW CONTINUES DOWNWIND OF THE FINGER LAKES. RADAR INTENSITY DOES NOT LOOK THAT STRONG BUT WITH SURFACE TEMPS THIS COLD, FLUFF FACTOR IS PROBABLY IN FULL FORCE. ADVISORY THROUGH 1 AM LOOKS GOOD WITH ANOTHER INCH OR TWO POSSIBLE IN THE MOST PERSISTENT BANDS. WIND CHILL VALUES ARE ALREADY IN THE -5 TO -10 RANGE AND EXPECTED TO DROP FURTHER OVERNIGHT, SO THE WIND CHILL ADVISORY LOOKS GOOD. A QUICK MENTION OF THE POTENTIAL SNOW FOR SUNDAY NIGHT INTO MONDAY. WE PUT A GRAPHIC ON SOCIAL MEDIA (TWITTER/FACEBOOK) TO SHOW THE HIGHEST THREAT FOR SNOW AT THIS POINT. PREVIOUS AFD IS BELOW. 145 PM UPDATE... ONLY MINOR TWEAKS MADE TO THE GRIDS THIS PD. AREA-WIDE WIND CHILL ADVSY STILL LOOKS ON TRACK FOR THE OVERNIGHT HRS...AS VERY STG 925-850 MB CAA THROUGH THIS EVE...SHOULD SEND AIR TEMPS INTO THE SINGLE DIGITS ABV OR BLO ZERO TNT...WITH THE PRES GRADIENT REMAINING RELATIVELY TIGHT THIS EVE...AND ONLY SLOWLY RELAXING LATE. MOST AREAS SHOULD SEE APPARENT TEMPS IN THE -10 TO -20 RANGE...WITH LOCALLY COLDER VALUES IN OUR FAR NRN AND ERN ZNS. AS FAR AS THE LES ADVSY GOES...NO CHGS ATTM. ALTHOUGH BLYR INSTAB (TERRESTRIAL CAPE VALUES OF 15-30 J/KG) TEMPORARILY RESULTED IN A MORE CELLULAR APPEARANCE TO THE SNOW SHWRS EARLIER THIS AFTN LOW-LVL STABILIZATION AND INCRG SHEAR SHOULD RESULT IN THE RE- EMERGENCE OF WELL DEFINED BANDS BY 21Z OR SO. IN FACT...EVIDENCE OF SUCH IS ALREADY SEEN ON KBGM RADAR IMAGERY ATTM. MOST HI-RES MODEL GUIDANCE HINTS THAT MULTI-BANDS/FINGER LKS BANDS WILL REMAIN AT PLAY TIL AT LEAST 06-12Z SAT. OVERALL...INTENSITY SHOULD WANE AFTER 06Z...AS MODEL SNDGS SHOW THE CAPPING INVERSION LWRG TO AOB 875-900 MB. WE`LL STICK WITH OUR 3-6" TOTALS FOR NOW...ALTHOUGH WUDN`T BE SURPRISED TO SEE LOCALLY HIER AMTS...SPCLY IN SERN TOMPKINS AND/OR NRN TIOGA. OUTSIDE OF MULTI-BAND AREAS...EITHER WIDELY SCTD -SHSN/FLRYS...OR JUST DRY WX...IS FORESEEN. PREV DISC... 10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL. NO OTHER SIG CHGS ATTM. EARLIER DISC... 830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM WITHIN A SW-NE ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN CATSKILLS. THIS FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV LIFTING THROUGH THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE UPDATED TO REFLECT SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3" ADDNL SNOWFALL WITHIN THE AFOREMENTIONED BAND AREA THROUGH 15-16Z. A SHORT-TERM SPS WAS ALSO ISSUED. OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2" ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY. GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT. && .SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/... 2 PM FRI UPDATE... OVERALL...THINGS LOOK FAIRLY QUIET SAT-SUN MRNG. WINDS SHOULD RELAX SAT...SO THE WIND CHILL EXPIRATION TIME OF 16Z STILL LOOKS GOOD ATTM. A WEAK SFC FRNT AND NRN STREAM S/WV ARE PROGGED TO TRAVERSE THE FA SAT NGT INTO THE FIRST PART OF SUN...WITH ONLY SCTD LGT SNOW SHWRS AND FLRYS ANTICIPATED...AND LTL IN THE WAY OF ACCUM. RECENT GLOBAL MODEL TRENDS (GFS/EC/GEM) HAVE PERSISTED WITH THE 12Z FRI CYCLE...INDICATING A MORE AMPLIFIED UPR-LVL WV...FARTHER N SFC LOW TRACK...AND RESULTANT INCREASED SNOWFALL POTENTIAL FOR CNY/NE PA. MUCH MORE ON THIS SYSTEM IN THE FOLLOWING SXN. FOR NOW...WE`VE BROUGHT THE LEADING EDGE OF STEADIER SNOW (CHC-LIKELY POPS) INTO AT LEAST SWRN/SRN PTNS OF THE FA BY MID TO LATE AFTN ON SUN. && .LONG TERM /TUESDAY THROUGH FRIDAY/... EXTENDED PERIOD WILL SEE A CONTINUATION OF AN UPPER LEVEL TROF ACROSS THE EASTERN UNITED STATES. TUESDAY/TUESDAY NIGHT, WILL BE PRIMARILY DRY AND COLD AS HIGH PRES MOVES FROM THE OHIO VALLEY TO THE MID ATLANTIC COAST. WEDNESDAY THROUGH THURSDAY, SFC LOW PRES WILL TRACK THROUGH THE WESTERN LAKES AND INTO SOUTHERN QUEBEC. THE TRAILING COLD FRONT WILL SWEEP THROUGH THE AREA WEDNESDAY NIGHT. HIGHS ON WED WILL RANGE FROM THE UPPER 20S TO LOWER 30S BEFORE ARCTIC AIR RETURNS TO THE REGION FOLLOWING THE COLD FRONT. SCATTERED SNOW SHOWERS WILL BE POSSIBLE THROUGH THIS PERIOD DUE TO FROPA AND COLD NORTHWEST FLOW ON THURSDAY. FRIDAY WILL BE DRY AS SFC HIGH PRES BUILDS OVER THE NORTHEAST. TEMPS THURSDAY THROUGH FRIDAY WILL BE BELOW NORMAL. && .AVIATION /08Z SATURDAY THROUGH WEDNESDAY/... COLD NORTHWEST FLOW WILL KEEP LAKE EFFECT SNOW SHOWERS AND CIG RESTRICTIONS OVER MOST OF THE TERMINALS THROUGH THIS AFTERNOON. AT KRME, NORTHWEST FLOW WILL KEEP LAKE CLOUDS WEST OF TERMINAL WITH VFR CONDITIONS EXPECTED THROUGH 00Z THEN AN APPROACHING SFC TROF OVERNIGHT WILL BRING MVFR CIG RESTRICTIONS. AT KSYR, MVFR CIGS THROUGH LATE MORNING WITH IFR SNOW SHOWERS POSSIBLE THROUGH 09Z. MVFR CIGS RETURN OVERNIGHT AFTER 00Z. AT KITH/KBGM, MVFR CIGS THROUGH TODAY WITH SNOW SHOWERS/FLURRIES CONTINUING AND IFR SNOW SHOWERS POSSIBLE THROUGH DAYBREAK. AT KELM/KAVP, MVFR/LOW VFR CIGS THROUGH MID MORNING THEN VFR UNTIL END OF TAF PERIOD. NORTHWEST WINDS 8-12 KNOTS WITH GUSTS AROUND 25 KNOTS GRADUALLY DECREASING THIS AFTERNOON. LIGHT SOUTHWEST WINDS THIS EVENING. OUTLOOK... SUN...MVFR RESTRICTIONS LIKELY FOR CIGS. SUN NGT / MON... RESTRICTIONS LIKELY (MVFR/IFR) IN SNOW. TUE...VFR. WED...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON FOR PAZ038>040-043-044-047-048-072. WIND CHILL ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ038>040-043-044-047-048-072. NY...WINTER STORM WATCH FROM SUNDAY AFTERNOON THROUGH MONDAY AFTERNOON FOR NYZ015>018-022>025-036-037-044>046-055>057- 062. WIND CHILL ADVISORY UNTIL 11 AM EST THIS MORNING FOR NYZ009- 015>018-022>025-036-037-044>046-055>057-062. && $$ SYNOPSIS...MLJ NEAR TERM...HEDEN/MLJ SHORT TERM...MLJ LONG TERM...RRM AVIATION...RRM
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1248 AM EST SAT JAN 31 2015 .SYNOPSIS... VERY COLD AIR WILL CONTINUE TO POUR INTO THE REGION TONIGHT...WITH LAKE-EFFECT SNOW PERSISTING DOWNWIND FROM THE FINGER LAKES...AND BITTERLY COLD WIND CHILLS AREA-WIDE. COLD TEMPERATURES WILL LAST THROUGH THE UPCOMING WEEKEND...WITH ONLY A FEW FLURRIES FORESEEN FROM SATURDAY INTO EARLY SUNDAY. AN APPROACHING WINTER STORM COULD BEGIN TO IMPACT THE AREA BY LATE SUNDAY AFTERNOON OR SUNDAY EVENING...WITH ACCUMULATING SNOW POSSIBLE. && .NEAR TERM /THROUGH TODAY/... 945 PM UPDATE... LAKE EFFECT SNOW CONTINUES DOWNWIND OF THE FINGER LAKES. RADAR INTENSITY DOES NOT LOOK THAT STRONG BUT WITH SURFACE TEMPS THIS COLD, FLUFF FACTOR IS PROBABLY IN FULL FORCE. ADVISORY THROUGH 1 AM LOOKS GOOD WITH ANOTHER INCH OR TWO POSSIBLE IN THE MOST PERSISTENT BANDS. WIND CHILL VALUES ARE ALREADY IN THE -5 TO -10 RANGE AND EXPECTED TO DROP FURTHER OVERNIGHT, SO THE WIND CHILL ADVISORY LOOKS GOOD. A QUICK MENTION OF THE POTENTIAL SNOW FOR SUNDAY NIGHT INTO MONDAY. WE PUT A GRAPHIC ON SOCIAL MEDIA (TWITTER/FACEBOOK) TO SHOW THE HIGHEST THREAT FOR SNOW AT THIS POINT. PREVIOUS AFD IS BELOW. 145 PM UPDATE... ONLY MINOR TWEAKS MADE TO THE GRIDS THIS PD. AREA-WIDE WIND CHILL ADVSY STILL LOOKS ON TRACK FOR THE OVERNIGHT HRS...AS VERY STG 925-850 MB CAA THROUGH THIS EVE...SHOULD SEND AIR TEMPS INTO THE SINGLE DIGITS ABV OR BLO ZERO TNT...WITH THE PRES GRADIENT REMAINING RELATIVELY TIGHT THIS EVE...AND ONLY SLOWLY RELAXING LATE. MOST AREAS SHOULD SEE APPARENT TEMPS IN THE -10 TO -20 RANGE...WITH LOCALLY COLDER VALUES IN OUR FAR NRN AND ERN ZNS. AS FAR AS THE LES ADVSY GOES...NO CHGS ATTM. ALTHOUGH BLYR INSTAB (TERRESTRIAL CAPE VALUES OF 15-30 J/KG) TEMPORARILY RESULTED IN A MORE CELLULAR APPEARANCE TO THE SNOW SHWRS EARLIER THIS AFTN LOW-LVL STABILIZATION AND INCRG SHEAR SHOULD RESULT IN THE RE- EMERGENCE OF WELL DEFINED BANDS BY 21Z OR SO. IN FACT...EVIDENCE OF SUCH IS ALREADY SEEN ON KBGM RADAR IMAGERY ATTM. MOST HI-RES MODEL GUIDANCE HINTS THAT MULTI-BANDS/FINGER LKS BANDS WILL REMAIN AT PLAY TIL AT LEAST 06-12Z SAT. OVERALL...INTENSITY SHOULD WANE AFTER 06Z...AS MODEL SNDGS SHOW THE CAPPING INVERSION LWRG TO AOB 875-900 MB. WE`LL STICK WITH OUR 3-6" TOTALS FOR NOW...ALTHOUGH WUDN`T BE SURPRISED TO SEE LOCALLY HIER AMTS...SPCLY IN SERN TOMPKINS AND/OR NRN TIOGA. OUTSIDE OF MULTI-BAND AREAS...EITHER WIDELY SCTD -SHSN/FLRYS...OR JUST DRY WX...IS FORESEEN. PREV DISC... 10 AM UPDATE... WE`VE ISSUED A LES ADVSY FOR TOMPKINS...TIOGA...BROOME...AND SUSQ CNTYS...AS CONFIDENCE HAS BECOME FAIRLY HIGH IN THE MAINTENANCE OF A WELL DVLPD FINGER LKS BAND...THROUGH AT LEAST 00-03Z THIS EVE. OUR FIRST STAB AT SNOW TOTALS IS 3-6"...BUT LOCALLY HIER AMTS ARE CERTAINLY PSBL. NO OTHER SIG CHGS ATTM. EARLIER DISC... 830 AM UPDATE... SN/+SN IS BEING OBSERVED ATTM WITHIN A SW-NE ORIENTED BAND ACRS NE PA AND PTNS OF THE WRN CATSKILLS. THIS FEATURE IS ON THE NWRN/DEFORMATION SIDE OF A S/WV LIFTING THROUGH THE RGN THIS MRNG. POP/WX/SNOWFALL GRIDS WERE UPDATED TO REFLECT SUCH DVLPMTS. WE`VE ADDED A CORRIDOR OF 2-3" ADDNL SNOWFALL WITHIN THE AFOREMENTIONED BAND AREA THROUGH 15-16Z. A SHORT-TERM SPS WAS ALSO ISSUED. OTHWS...THE FCST IS PRETTY WELL IN HAND. FAIRLY DEEP LYR OF INSTAB NOTED ON THE 12Z KBUF SNDG...INDICATIVE OF THE AMS WE`LL HAVE THROUGH EARLY AFTN...AHD OF THE NEXT INCOMING S/WV. LIKELY POPS FOR SNOW SHWRS OVER MOST OF CNY...WITH MORE SCTD ACTIVITY ACRS MUCH OF NE PA...STILL SEEMS REASONABLE...WITH A FLUFFY 1-2" ANTICIPATED IN THE MOST PERSISTENT SHSN. IT`S WORTH NOTING THAT THE LATEST HRRR AND HI-RES ARW OUTPUT IN PARTICULAR SHOW A WELL FORMED MULTI-BAND/FINGER LKS BAND FROM LTR THIS MRNG...THROUGH THE AFTN...AND INTO THE EVE HRS...DOWN THE AXIS OF CAYUGA LAKE...AND THEN SEWD FROM THERE THROUGH AT LEAST TOMPKINS/TIOGA CNTYS. SINCE THERE ARE ALREADY SOME INDICATIONS OF BANDING IN THIS GENERAL AREA ATTM...WE`LL MONITOR THAT CLOSELY THROUGH THE DAY. GIVEN STG CAA THROUGHOUT THE COLUMN...SHARPLY FALLING TEMPS STILL LOOK LIKELY...AND OUR PREVIOUSLY ADVERTISED TREND WAS KEPT IN TACT. && .SHORT TERM /TONIGHT THROUGH 6 PM SUNDAY/... 2 PM FRI UPDATE... OVERALL...THINGS LOOK FAIRLY QUIET SAT-SUN MRNG. WINDS SHOULD RELAX SAT...SO THE WIND CHILL EXPIRATION TIME OF 16Z STILL LOOKS GOOD ATTM. A WEAK SFC FRNT AND NRN STREAM S/WV ARE PROGGED TO TRAVERSE THE FA SAT NGT INTO THE FIRST PART OF SUN...WITH ONLY SCTD LGT SNOW SHWRS AND FLRYS ANTICIPATED...AND LTL IN THE WAY OF ACCUM. RECENT GLOBAL MODEL TRENDS (GFS/EC/GEM) HAVE PERSISTED WITH THE 12Z FRI CYCLE...INDICATING A MORE AMPLIFIED UPR-LVL WV...FARTHER N SFC LOW TRACK...AND RESULTANT INCREASED SNOWFALL POTENTIAL FOR CNY/NE PA. MUCH MORE ON THIS SYSTEM IN THE FOLLOWING SXN. FOR NOW...WE`VE BROUGHT THE LEADING EDGE OF STEADIER SNOW (CHC-LIKELY POPS) INTO AT LEAST SWRN/SRN PTNS OF THE FA BY MID TO LATE AFTN ON SUN. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... CONFIDENCE IS GROWING THAT THE AREA WILL BE AFFECTED BY A MOISTURE LADEN STORM SYSTEM AS IT MOVES FROM THE OHIO VALLEY OFF THE EAST COAST SUNDAY NIGHT INTO MONDAY. EXPECT SNOW TO CONTINUE OVERSPREADING THE REGION SUNDAY EVENING AND POTENTIALLY BECOME HEAVY AT TIMES OVERNIGHT INTO EARLY MONDAY. AS THIS EVENT IS STILL MORE THAN 48 HOURS OUT, THERE IS STILL A LOT OF UNCERTAINTY IN THE DETAILS OF THE SYSTEM AND IT`S EXACT TRACK BUT AS DISCUSSED ABOVE FORECAST GUIDANCE HAS COME INTO BETTER AGREEMENT WITH THIS UPDATE CYCLE. THE TRACK OF THE LOW SOUTH OF THE CWA SHOULD RESULT IN THE HEAVIER AMOUNTS (POTENTIALLY 6+ INCHES) GENERALLY OCCURRING ACROSS NE PA NORTHWARD ACROSS THE SOUTHERN TIER OF UPSTATE NEW YORK THEN EAST INTO THE CATSKILLS WITH LIGHTER AMOUNTS FARTHER NORTH. WORTH NOTING, HOWEVER, IS THAT IF THE LOW TRACK WERE TO TREND EVEN FARTHER NORTH THIS COULD INTRODUCE MIXED PRECIP INTO NE PA CUTTING AMOUNTS DOWN THERE AND RESULTING IN MORE WIDESPREAD HIGHER TOTALS OVER NY. SO, AS MENTIONED, STILL UNCERTAINTY SO WE WILL HOLD OFF ON WATCH AT THIS TIME. FINALLY, THE ARCTIC AIR IN PLACE AHEAD OF THIS SYSTEM WILL ALSO RESULT IN THIS BEING A VERY COLD EVENT WITH TEMPS GENERALLY IN THE TEENS AND EVEN SINGLE DIGITS IN THE FAR NORTH WHICH WILL BE ACCOMPANIED BY INCREASING WINDS LATER MONDAY. EXPECT SNOW TO WIND DOWN BY LATER MONDAY WITH SOME LAKE EFFECT POSSIBLE IN IT`S WAKE MONDAY NIGHT. ALSO EXPECT VERY COLD TEMPS BY LATER MONDAY NIGHT AS ARCTIC HIGH BUILDS IN WITH WIDESPREAD SUBZERO READINGS. TUESDAY WILL BE GENERALLY FAIR BUT COLD WITH BRIEF MODERATION TO SEASONAL WEDNESDAY BEFORE ANOTHER ARCTIC FRONT MOVES THROUGH LATE WEDNESDAY WITH SNOW SHOWERS AND COLDER TEMPS TO FOLLOW FOR THE END OF THE WEEK. NW FLOW ALSO WILL BRING THE POTENTIAL FOR SOME LAKE EFFECT INTO THURSDAY. && .AVIATION /06Z SATURDAY THROUGH WEDNESDAY/... COLD NORTHWEST FLOW WILL KEEP LAKE EFFECT SNOW SHOWERS AND CIG RESTRICTIONS OVER MOST OF THE TERMINALS THROUGH THIS AFTERNOON. AT KRME, NORTHWEST FLOW WILL KEEP LAKE CLOUDS WEST OF TERMINAL WITH VFR CONDITIONS EXPECTED THROUGH 00Z THEN AN APPROACHING SFC TROF OVERNIGHT WILL BRING MVFR CIG RESTRICTIONS. AT KSYR, MVFR CIGS THROUGH LATE MORNING WITH IFR SNOW SHOWERS POSSIBLE THROUGH 09Z. MVFR CIGS RETURN OVERNIGHT AFTER 00Z. AT KITH/KBGM, MVFR CIGS THROUGH TODAY WITH SNOW SHOWERS/FLURRIES CONTINUING AND IFR SNOW SHOWERS POSSIBLE THROUGH DAYBREAK. AT KELM/KAVP, MVFR/LOW VFR CIGS THROUGH MID MORNING THEN VFR UNTIL END OF TAF PERIOD. NORTHWEST WINDS 8-12 KNOTS WITH GUSTS AROUND 25 KNOTS GRADUALLY DECREASING THIS AFTERNOON. LIGHT SOUTHWEST WINDS THIS EVENING. OUTLOOK... SUN...MVFR RESTRICTIONS LIKELY FOR CIGS. SUN NGT / MON... RESTRICTIONS LIKELY (MVFR/IFR) IN SNOW. TUE...VFR. WED...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WIND CHILL ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ038>040-043-044-047-048-072. LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST EARLY THIS MORNING FOR PAZ039. NY...WIND CHILL ADVISORY UNTIL 11 AM EST THIS MORNING FOR NYZ009- 015>018-022>025-036-037-044>046-055>057-062. LAKE EFFECT SNOW ADVISORY UNTIL 1 AM EST EARLY THIS MORNING FOR NYZ025-055-056. && $$ SYNOPSIS...MLJ NEAR TERM...HEDEN/MLJ SHORT TERM...MLJ LONG TERM...PCF AVIATION...RRM
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1030 AM EST SAT JAN 31 2015 .SYNOPSIS...HIGH PRESSURE CONTINUES TO BUILD OVER THE REGION TODAY. THE CENTER OF THE HIGH MOVES OFFSHORE TONIGHT AHEAD OF A LOW PRESSURE SYSTEM THAT MOVES INTO THE MID-ATLANTIC MONDAY MORNING. THE TRAILING COLD FRONT PUSHES EAST OF THE CAROLINAS MONDAY...FOLLOWED BY HIGH PRESSURE AGAIN FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /TODAY AND TONIGHT/... AS OF 1030 AM SATURDAY... LITTLE CHANGE TO THE FORECAST THIS MORNING. STRONG MID-LEVEL RIDGING AND SURFACE HIGH PRESSURE ENCOMPASSES MOST OF THE SOUTHEASTERN QUARTER OF THE CONUS...WITH PW VALUES DOWN TO LESS THAN 0.15" ON MANY OF THE REGIONAL RAOBS. MID/HIGH CLOUDS EXPANDING ACROSS THE MID/LOWER MISSISSIPPI VALLEY SHOULD REMAIN MOSTLY WEST OF THE AREA DURING THE DAY TODAY...WITH JUST A FEW PATCHES OF CIRRUS OVER CENTRAL NC. FORECAST HIGHS ARE IN LINE WITH THE OBSERVED MORNING 1000-850MB THICKNESS (1272M AT KGSO) AND SLIGHT RECOVERY OVER THE SOUTHWEST AS THE SURFACE HIGH SHIFTS SOUTHEAST THIS AFTERNOON. MID 40S NORTHEAST TO AROUND 50 SOUTHWEST. -BLS TEMPERATURES SHOULD FALL SOMEWHAT QUICKLY THIS EVENING THEN TEND TO STABILIZE AS CLOUDS MOVE IN. LOWS TONIGHT 25 TO 30 NEAR AND EAST OF INTERSTATE 95 AND AROUND 30 ELSEWHERE. MINIMUM RELATIVE HUMIDITIES TODAY COULD FALL TO NEAR 15 PERCENT BASED ON THE EXPECTED SURFACE DEW POINTS...BUT WINDS WILL BE MUCH LIGHTER COMPARED TO FRIDAY AND BY THE TIME DEW POINTS WOULD FALL TO THOSE LEVELS THE FREQUENCY OF ANY MODEST GUSTS SHOULD BE MUCH LOWER. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 AM SATURDAY... SUNDAY: MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW OVER THE SOUTHWEST US WILL EJECT EASTWARD AND MOVE THROUGH THE AREA IN ADVANCE OF THE NORTHERN STREAM TROUGH AMPLIFYING OVER THE CENTRAL PLAINS. ASSOCIATED WEAK DPVA WILL RESULT IN EXTENSIVE MID/HIGH LEVEL CLOUDINESS OVER THE AREA ON SUNDAY...HOWEVER GRADUAL MOISTENING OF AN INITIALLY DRY ~10KFT SUB- CLOUD LAYER LEFT(REMAINS OF THE MODERATING CP AIRMASS)WILL KEEP IT DRY ACROSS MUCH OF CENTRAL NC DURING THE DAYLIGHT HOURS. THE EXCEPTION WILL BE ACROSS THE FAR WESTERN ZONES WHERE A FEW SHOWERS COULD DEVELOP LATE IN THE AFTERNOON AS THE WARM MOIST CONVEYOR FEED BEGINS TO PUSH EAST OF THE MOUNTAINS. HIGHS SUNDAY IN THE LOWER 50S NORTH TO MID 50S SOUTH. SUNDAY NIGHT: AFOREMENTIONED NORTHERN STREAM TROUGH WILL CONTINUE TO PROGRESS EASTWARD...REACHING THE SOUTHERN/CENTRAL APPALACHIANS BY DAYBREAK MONDAY. DEEPENING SURFACE LOW....MOVING EASTWARD ALONG THE LEADING EDGE OF THE ASSOCIATED 180-200 METER 500MB HEIGHT FALLS... WILL TRACK ACROSS THE SOUTHERN OHIO VALLEY AND THROUGH THE VIRGINIAS DURING THE PREDAWN HOURS...DRAGGING A SFC COLD FRONT INTO THE NC FOOTHILLS. STRONG DEEP MOISTURE TRANSPORT IN ADVANCE OF THE FRONT...WITHIN THE STRENGTHENING 60-65KT SOUTHERLY LLJ WILL SUPPORT A 4-6 HOUR WINDOW OF CATEGORICAL POPS ACROSS THE AREA SUNDAY NIGHT. QPF AMOUNTS LOOK TO BE IN THE 0.25-0.50" RANGE...LIMITED BY THE INTRUSION OF A MID-LEVEL SLOT RACING IN FROM THE WEST. HAVE NO PLANS TO INCLUDE ANY THUNDER AT THIS TIME AS MODELS CONTINUE TO SHOW MODEST MID-LEVEL LAPSE RATES (6.5-6.8 C/KM)WITH LESS THAN <200 J/KG OF MUCAPE ACROSS THE AREA. EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING BEFORE MIDNIGHT...WITH TEMPERATURES THEN WARMING OVERNIGHT OWING TO STRONG WAA. LOWS SUNDAY NIGHT IN THE MID 40S NORTHWEST TO LOWER 50S SOUTH. MONDAY AND MONDAY NIGHT: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN DURING THE MID TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST- FRONTAL DRY COLD AIR ADVECTION REGIME...WITH BREEZY/BLUSTERY CONDITIONS AS BUFR SOUNDINGS INDICATING 38-40KTS AT THE TOP OF THE MIXED LAYER(SIMILAR TO IF NOT STRONGER THAN THE GUSTS WE HAD YESTERDAY). LOOK FOR TEMPERATURES FALLING THROUGH THE AFTERNOON AS YET ANOTHER CP AIRMASS BUILDS INTO THE AREA MONDAY NIGHT AND INTO THE DAY ON TUESDAY. MORNING HIGHS RANGING FROM MID UPPER 40S NORTHWEST TO MID 50S SOUTHEAST. IF PROJECTED LOW-LEVEL THICKNESSES AOA 1270M VERIFY AND WE DECOUPLE AS MODELS SUGGEST...EXPECT LOWS TUESDAY MORNING IN THE LOWER 20S...WITH UPPER TEENS POSSIBLE IN THE TYPICALLY COLDER LOCATIONS. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 300 AM SATURDAY... BOTH THE ECMWF AND THE GFS PASS A MID-LEVEL SHORTWAVE THROUGH CENTRAL NORTH CAROLINA TUESDAY AS A BROAD...PROGRESSIVE TROUGH ALOFT MOVES THROUGH. HOWEVER...WITH SURFACE HIGH PRESSURE IN PLACE AND EXTENDING ACROSS THE GULF A PERIOD OF PARTLY TO POSSIBLY MOSTLY CLOUDY SKIES SHOULD ONLY ACCOMPANY THE SHORTWAVE. AFTER EXPECTED BRIEF CLEARING BEHIND THE MID-LEVEL WAVE...IN THE FAST AND SLOWLY BACKING FLOW ALOFT BOTH THE ECMWF AND THE GFS FORECAST INCREASING UPPER-LEVEL MOISTURE WEDNESDAY INTO WEDNESDAY NIGHT WITH A COLD FRONT MOVING THROUGH WEDNESDAY NIGHT. BOTH THE GFS AND ECMWF ARE DRY INTO THE OVERNIGHT HOURS OF WEDNESDAY WITH SURFACE HIGH PRESSURE AHEAD OF THE COLD FRONT EXTENDING OVER THE GULF COAST AND LIMITING LOW-LEVEL MOISTURE RETURN. FOR THIS FORECAST...WILL HAVE DRY CONDITIONS TUESDAY INTO THE OVERNIGHT HOURS OF WEDNESDAY. MEX MOS AND ECMWF MOS GUIDANCE POPS ARE BELOW CLIMATOLOGY DURING THIS PERIOD. GUIDANCE DIFFERENCES ARE FAIRLY OBVIOUS BY LATE WEDNESDAY NIGHT. MUCH WILL DEPEND ON HOW DEEP THE UPPER TROUGH MOVING THROUGH SOUTHERN CANADA ENDS UP BEING DURING THE MIDDLE OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT OVER THE LAST COUPLE OF RUNS OR SO WITH A DEEPER UPPER TROUGH EXTENDING THROUGH THE GREAT LAKES INTO THE OHIO VALLEY. THIS SUPPRESSES THE TRACK OF AN UPPER LOW FORECAST BY BOTH THE GFS AND THE ECMWF TO DEVELOP OVER OLD MEXICO...KEEPING DEEPER MOISTURE TO OUR SOUTH AND RESULTING IN DRY CONDITIONS FOR CENTRAL NORTH CAROLINA THROUGH THE END OF THE WEEK. THE GFS...ALSO CONSISTENT WITH ITSELF...IS NOTICEABLY LESS AMPLIFIED WITH THE CANADIAN UPPER TROUGH SUCH THAT THE WEAKENING UPPER LOW IS ABLE TO MOVE TOWARD THE CAROLINAS BY THURSDAY ALONG WITH MORE MOISTURE. THE GFS FORECASTS PRECIPITATION OVER CENTRAL NORTH CAROLINA BY 12Z THURSDAY WHICH...IF IT OCCURS...WOULD BE LIQUID AS GFS PARTIAL THICKNESSES ARE WELL INTO THE RAIN REGIME AT THAT TIME. DUE TO THE GUIDANCE UNCERTAINTY...THE PRUDENT COURSE APPEARS TO BE MAINTAINING CONSISTENCY WITH THE ONGOING FORECAST...A CHANCE OF RAIN IN CENTRAL NORTH CAROLINA OVERNIGHT WEDNESDAY INTO THURSDAY WITH CHANCES LOWEST AND BASICALLY NEAR SLIGHT IN THE TRIAD TO HIGHER CHANCES ALONG AND EAST OF A LINE FROM ABOUT KMEB TO KRWI. IF THE GFS VERIFIES EXACTLY THERE WOULD BE CONCERN ABOUT PRECIPITATION TYPE IN THE LINGERING MOISTURE BY THURSDAY NIGHT...BUT A DRY ECMWF WITH NEAR SOUTHEAST CONUS LOW PRESSURE MOVING OFFSHORE AND A DRY PREVIOUS FORECAST WILL RESULT IN A DRY CURRENT FORECAST THURSDAY NIGHT THROUGH FRIDAY NIGHT...THOUGH TURNING CHILLY AT THE END OF THE WEEK. THE WARMEST DAY OF THE PERIOD SHOULD BE WEDNESDAY. 1000-850MB THICKNESSES WOULD SUGGEST HIGHS AT LEAST IN THE MID TO UPPER 50S... FAIRLY COINCIDENT WITH THE MEX AND MEE MOS GUIDANCE...BUT WILL LEAN ABOUT A CATEGORY COOLER TOWARD THE HPC GUIDANCE FOR HIGHS IN THE LOWER TO MID 50S DUE TO THE ANTICIPATED PRESENCE OF AT LEAST SOME UPPER-LEVEL CLOUD COVER. THICKNESSES COOL AT THE END OF THE WEEK AND...DESPITE DIFFERENCES IN OTHER DETAILS...1000-850MB THICKNESSES...AND HPC AND MUCH OF THE MOS GUIDANCE...KEEP HIGHS ONLY IN THE MID 30S TO LOWER 40S FRIDAY. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... AS OF 630 AM SATURDAY... VFR CONDITIONS CONTINUE FOR THE 12Z VALID TAF PERIOD. SATELLITE IMAGES STILL SHOWED A FEW JET-STREAK CIRRUS IN CENTRAL NORTH CAROLINA AROUND DAYBREAK...AND DURING THE DAY TODAY AND THROUGH THE OVERNIGHT HOURS HIGH- AND MID-LEVEL CLOUDS WILL GRADUALLY MOVE IN FROM THE WEST. EXPECT MORE OF THE MID-LEVEL CLOUDS TO APPEAR IN CENTRAL NORTH CAROLINA TONIGHT...FROM AROUND 03Z AND LATER. FORECAST SOUNDINGS ESPECIALLY FROM THE GFS SUGGEST A FEW WIND GUSTS INTO THE TEENS KNOTS WITH INITIAL MIXING THIS MORNING...BUT THE TREND OF ANY GUSTINESS SHOULD DIMINISH BY EARLY AFTERNOON AS THE SURFACE HIGH CONTINUES TO BUILD IN. RAP SOUNDINGS ARE A COUPLE OF KNOTS LIGHTER...SO IT IS POSSIBLE THAT THE TAFS REFLECT GUSTS IN THE TEENS KNOTS THAT ARE ON THE HIGHER END OF WHAT MAY OCCUR WITH MIXING THIS MORNING INTO EARLY AFTERNOON...ESPECIALLY TOWARD THE TRIAD. LIGHT SOUTH TO SOUTHWEST WIND BY THIS EVENING. BEYOND THE 12Z VALID TAF PERIOD...VFR SUNDAY...WITH AN INCREASING POSSIBILITY OF MVFR CLOUDS DURING THE AFTERNOON...THEN SUB-VFR CONDITIONS AND AREAS OF RAIN LIKELY OVERNIGHT SUNDAY AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH CENTRAL NORTH CAROLINA EARLY MONDAY. AHEAD OF THE COLD FRONT SUNDAY NIGHT...WINDS ALOFT WILL INCREASE TO SOUTHWEST AOA 50KT BY 2500FT. VFR CONDITIONS RETURN BY MONDAY AFTERNOON WITH GUSTY WEST-NORTHWEST AND NORTHWEST SURFACE WINDS. VFR CONDITIONS SHOULD THEN CONTINUE THROUGH WEDNESDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF/BLS SHORT TERM...CBL LONG TERM...DJF AVIATION...DJF
AREA FORECAST DISCUSSION
NWS RALEIGH NC
631 AM EST SAT JAN 31 2015 .SYNOPSIS...HIGH PRESSURE CONTINUES TO BUILD OVER THE REGION TODAY. THE CENTER OF THE HIGH MOVES OFFSHORE TONIGHT AHEAD OF A LOW PRESSURE SYSTEM THAT MOVES INTO THE MID-ATLANTIC MONDAY MORNING. THE TRAILING COLD FRONT PUSHES EAST OF THE CAROLINAS MONDAY...FOLLOWED BY HIGH PRESSURE AGAIN FOR THE MIDDLE OF NEXT WEEK. && .NEAR TERM /TODAY AND TONIGHT/... AS OF 115 AM SATURDAY... ASIDE FROM SOME JET-STREAK CIRRUS OVER PART OF CENTRAL NORTH CAROLINA ON THE LATEST IR SATELLITE IMAGES...CLEAR CONDITIONS WERE IN PLACE OVER CENTRAL NORTH CAROLINA. THE JET ALOFT IS FORECAST BY THE GFS AND NAM TO MOVE NORTHEAST AND OUT OF CENTRAL NORTH CAROLINA DURING THE DAY...ALTHOUGH A FLAT RIDGE AXIS ALOFT WILL APPROACH THE STATE TONIGHT WITH A GRADUAL INCREASE IN HIGH CLOUDS AND MAYBE EVEN MORE MID-LEVEL CLOUDS IN THE 12000FT TO 15000FT RANGE OVERNIGHT BASED ON THE MOISTURE PROFILES FROM BOTH THE NAM AND GFS BUFR SOUNDINGS. K INDICES ARE NEGATIVE UNTIL LATE TONIGHT IN THE INTERSTATE 85 CORRIDOR WHERE THE CLOUD BASES MAY BE A LITTLE LOWER RELATIVE TO THE REST OF CENTRAL NORTH CAROLINA...BUT THE AIR MASS BELOW 700MB REMAINS DRY AT LEAST THROUGH TONIGHT. THE CANADIAN CLOUD COVER MODEL WHICH TENDS TO DO PRETTY WELL WITH THE ONSET AND COVERAGE OF HIGHER CLOUDS INCREASES THE COVERAGE OF THOSE CLOUDS GRADUALLY THIS AFTERNOON THROUGH TONIGHT WITH AREAS FROM KFAY TO KRWI AND EAST TAKING LONGER TO GET AT LEAST BROKEN COVERAGE. GFS BUFR SOUNDINGS ARE SLIGHTLY HIGHER THAN NAM BUFR SOUNDINGS WITH REGARD TO THE POTENTIAL FOR A FEW WIND GUSTS IN THE TEENS KNOTS THIS MORNING. BASED ON SOME STIRRING OF THE WINDS CONTINUING EARLY THIS MORNING WILL LEAN TOWARD THE GFS AND ANTICIPATE A FEW WIND GUSTS IN THE TEENS KNOTS THIS MORNING BEFORE ANY GUSTINESS SHOULD DIMINISH INTO THE AFTERNOON AS THE SURFACE HIGH CONTINUES TO BUILD IN. WINDS WILL BECOME LIGHT SOUTH TO SOUTHWEST BY THIS EVENING. UNDER GOOD SUNSHINE...1000-850MB THICKNESSES AND A BLEND OF THE MAV AND MET MOS GUIDANCE SUGGEST HIGHS FROM THE MID 40S TO LOWER 50S...HIGHEST SOUTHWEST WHERE THE THICKNESSES WILL BE GREATER AND WINDS BECOME WEST TO SOUTHWEST SOONER. TEMPERATURES SHOULD FALL SOMEWHAT QUICKLY THIS EVENING THEN TEND TO STABILIZE AS CLOUDS MOVE IN. LOWS TONIGHT 25 TO 30 NEAR AND EAST OF INTERSTATE 95 AND AROUND 30 ELSEWHERE. MINIMUM RELATIVE HUMIDITIES TODAY COULD FALL TO NEAR 15 PERCENT BASED ON THE EXPECTED SURFACE DEW POINTS...BUT WINDS WILL BE MUCH LIGHTER COMPARED TO FRIDAY AND BY THE TIME DEW POINTS WOULD FALL TO THOSE LEVELS THE FREQUENCY OF ANY MODEST GUSTS SHOULD BE MUCH LOWER. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 AM SATURDAY... SUNDAY: MINOR MID-LEVEL IMPULSES EMANATING FROM THE UPPER TROUGH/CLOSED LOW OVER THE SOUTHWEST US WILL EJECT EASTWARD AND MOVE THROUGH THE AREA IN ADVANCE OF THE NORTHERN STREAM TROUGH AMPLIFYING OVER THE CENTRAL PLAINS. ASSOCIATED WEAK DPVA WILL RESULT IN EXTENSIVE MID/HIGH LEVEL CLOUDINESS OVER THE AREA ON SUNDAY...HOWEVER GRADUAL MOISTENING OF AN INITIALLY DRY ~10KFT SUB- CLOUD LAYER LEFT(REMAINS OF THE MODERATING CP AIRMASS)WILL KEEP IT DRY ACROSS MUCH OF CENTRAL NC DURING THE DAYLIGHT HOURS. THE EXCEPTION WILL BE ACROSS THE FAR WESTERN ZONES WHERE A FEW SHOWERS COULD DEVELOP LATE IN THE AFTERNOON AS THE WARM MOIST CONVEYOR FEED BEGINS TO PUSH EAST OF THE MOUNTAINS. HIGHS SUNDAY IN THE LOWER 50S NORTH TO MID 50S SOUTH. SUNDAY NIGHT: AFOREMENTIONED NORTHERN STREAM TROUGH WILL CONTINUE TO PROGRESS EASTWARD...REACHING THE SOUTHERN/CENTRAL APPALACHIANS BY DAYBREAK MONDAY. DEEPENING SURFACE LOW....MOVING EASTWARD ALONG THE LEADING EDGE OF THE ASSOCIATED 180-200 METER 500MB HEIGHT FALLS... WILL TRACK ACROSS THE SOUTHERN OHIO VALLEY AND THROUGH THE VIRGINIAS DURING THE PREDAWN HOURS...DRAGGING A SFC COLD FRONT INTO THE NC FOOTHILLS. STRONG DEEP MOISTURE TRANSPORT IN ADVANCE OF THE FRONT...WITHIN THE STRENGTHENING 60-65KT SOUTHERLY LLJ WILL SUPPORT A 4-6 HOUR WINDOW OF CATEGORICAL POPS ACROSS THE AREA SUNDAY NIGHT. QPF AMOUNTS LOOK TO BE IN THE 0.25-0.50" RANGE...LIMITED BY THE INTRUSION OF A MID-LEVEL SLOT RACING IN FROM THE WEST. HAVE NO PLANS TO INCLUDE ANY THUNDER AT THIS TIME AS MODELS CONTINUE TO SHOW MODEST MID-LEVEL LAPSE RATES (6.5-6.8 C/KM)WITH LESS THAN <200 J/KG OF MUCAPE ACROSS THE AREA. EXPECT A NON-DIURNAL TEMP TREND SUNDAY NIGHT...WITH LOWS OCCURRING BEFORE MIDNIGHT...WITH TEMPERATURES THEN WARMING OVERNIGHT OWING TO STRONG WAA. LOWS SUNDAY NIGHT IN THE MID 40S NORTHWEST TO LOWER 50S SOUTH. MONDAY AND MONDAY NIGHT: AGGRESSIVE MID-LEVEL DRY AIR INTRUSION WILL OVERTAKE THE AREA FROM THE WEST BETWEEN 12 TO 18Z MONDAY IN ADVANCE OF THE PASSAGE OF THE NORTHERN STREAM TROUGH PASSAGE MONDAY AFTERNOON. THIS WILL BRING AN ABRUPT END TO PRECIP ACROSS THE AREA MONDAY MORNING...WITH RAIN/SHOWERS EXITING THE COASTAL PLAIN DURING THE MID TO LATE MORNING. EQUALLY IMPRESSIVE WILL BE STRONG POST- FRONTAL DRY COLD AIR ADVECTION REGIME...WITH BREEZY/BLUSTERY CONDITIONS AS BUFR SOUNDINGS INDICATING 38-40KTS AT THE TOP OF THE MIXED LAYER(SIMILAR TO IF NOT STRONGER THAN THE GUSTS WE HAD YESTERDAY). LOOK FOR TEMPERATURES FALLING THROUGH THE AFTERNOON AS YET ANOTHER CP AIRMASS BUILDS INTO THE AREA MONDAY NIGHT AND INTO THE DAY ON TUESDAY. MORNING HIGHS RANGING FROM MID UPPER 40S NORTHWEST TO MID 50S SOUTHEAST. IF PROJECTED LOW-LEVEL THICKNESSES AOA 1270M VERIFY AND WE DECOUPLE AS MODELS SUGGEST...EXPECT LOWS TUESDAY MORNING IN THE LOWER 20S...WITH UPPER TEENS POSSIBLE IN THE TYPICALLY COLDER LOCATIONS. && .LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 300 AM SATURDAY... BOTH THE ECMWF AND THE GFS PASS A MID-LEVEL SHORTWAVE THROUGH CENTRAL NORTH CAROLINA TUESDAY AS A BROAD...PROGRESSIVE TROUGH ALOFT MOVES THROUGH. HOWEVER...WITH SURFACE HIGH PRESSURE IN PLACE AND EXTENDING ACROSS THE GULF A PERIOD OF PARTLY TO POSSIBLY MOSTLY CLOUDY SKIES SHOULD ONLY ACCOMPANY THE SHORTWAVE. AFTER EXPECTED BRIEF CLEARING BEHIND THE MID-LEVEL WAVE...IN THE FAST AND SLOWLY BACKING FLOW ALOFT BOTH THE ECMWF AND THE GFS FORECAST INCREASING UPPER-LEVEL MOISTURE WEDNESDAY INTO WEDNESDAY NIGHT WITH A COLD FRONT MOVING THROUGH WEDNESDAY NIGHT. BOTH THE GFS AND ECMWF ARE DRY INTO THE OVERNIGHT HOURS OF WEDNESDAY WITH SURFACE HIGH PRESSURE AHEAD OF THE COLD FRONT EXTENDING OVER THE GULF COAST AND LIMITING LOW-LEVEL MOISTURE RETURN. FOR THIS FORECAST...WILL HAVE DRY CONDITIONS TUESDAY INTO THE OVERNIGHT HOURS OF WEDNESDAY. MEX MOS AND ECMWF MOS GUIDANCE POPS ARE BELOW CLIMATOLOGY DURING THIS PERIOD. GUIDANCE DIFFERENCES ARE FAIRLY OBVIOUS BY LATE WEDNESDAY NIGHT. MUCH WILL DEPEND ON HOW DEEP THE UPPER TROUGH MOVING THROUGH SOUTHERN CANADA ENDS UP BEING DURING THE MIDDLE OF THE WEEK. THE ECMWF HAS BEEN CONSISTENT OVER THE LAST COUPLE OF RUNS OR SO WITH A DEEPER UPPER TROUGH EXTENDING THROUGH THE GREAT LAKES INTO THE OHIO VALLEY. THIS SUPPRESSES THE TRACK OF AN UPPER LOW FORECAST BY BOTH THE GFS AND THE ECMWF TO DEVELOP OVER OLD MEXICO...KEEPING DEEPER MOISTURE TO OUR SOUTH AND RESULTING IN DRY CONDITIONS FOR CENTRAL NORTH CAROLINA THROUGH THE END OF THE WEEK. THE GFS...ALSO CONSISTENT WITH ITSELF...IS NOTICEABLY LESS AMPLIFIED WITH THE CANADIAN UPPER TROUGH SUCH THAT THE WEAKENING UPPER LOW IS ABLE TO MOVE TOWARD THE CAROLINAS BY THURSDAY ALONG WITH MORE MOISTURE. THE GFS FORECASTS PRECIPITATION OVER CENTRAL NORTH CAROLINA BY 12Z THURSDAY WHICH...IF IT OCCURS...WOULD BE LIQUID AS GFS PARTIAL THICKNESSES ARE WELL INTO THE RAIN REGIME AT THAT TIME. DUE TO THE GUIDANCE UNCERTAINTY...THE PRUDENT COURSE APPEARS TO BE MAINTAINING CONSISTENCY WITH THE ONGOING FORECAST...A CHANCE OF RAIN IN CENTRAL NORTH CAROLINA OVERNIGHT WEDNESDAY INTO THURSDAY WITH CHANCES LOWEST AND BASICALLY NEAR SLIGHT IN THE TRIAD TO HIGHER CHANCES ALONG AND EAST OF A LINE FROM ABOUT KMEB TO KRWI. IF THE GFS VERIFIES EXACTLY THERE WOULD BE CONCERN ABOUT PRECIPITATION TYPE IN THE LINGERING MOISTURE BY THURSDAY NIGHT...BUT A DRY ECMWF WITH NEAR SOUTHEAST CONUS LOW PRESSURE MOVING OFFSHORE AND A DRY PREVIOUS FORECAST WILL RESULT IN A DRY CURRENT FORECAST THURSDAY NIGHT THROUGH FRIDAY NIGHT...THOUGH TURNING CHILLY AT THE END OF THE WEEK. THE WARMEST DAY OF THE PERIOD SHOULD BE WEDNESDAY. 1000-850MB THICKNESSES WOULD SUGGEST HIGHS AT LEAST IN THE MID TO UPPER 50S... FAIRLY COINCIDENT WITH THE MEX AND MEE MOS GUIDANCE...BUT WILL LEAN ABOUT A CATEGORY COOLER TOWARD THE HPC GUIDANCE FOR HIGHS IN THE LOWER TO MID 50S DUE TO THE ANTICIPATED PRESENCE OF AT LEAST SOME UPPER-LEVEL CLOUD COVER. THICKNESSES COOL AT THE END OF THE WEEK AND...DESPITE DIFFERENCES IN OTHER DETAILS...1000-850MB THICKNESSES...AND HPC AND MUCH OF THE MOS GUIDANCE...KEEP HIGHS ONLY IN THE MID 30S TO LOWER 40S FRIDAY. && .AVIATION /12Z SATURDAY THROUGH WEDNESDAY/... AS OF 630 AM SATURDAY... VFR CONDITIONS CONTINUE FOR THE 12Z VALID TAF PERIOD. SATELLITE IMAGES STILL SHOWED A FEW JET-STREAK CIRRUS IN CENTRAL NORTH CAROLINA AROUND DAYBREAK...AND DURING THE DAY TODAY AND THROUGH THE OVERNIGHT HOURS HIGH- AND MID-LEVEL CLOUDS WILL GRADUALLY MOVE IN FROM THE WEST. EXPECT MORE OF THE MID-LEVEL CLOUDS TO APPEAR IN CENTRAL NORTH CAROLINA TONIGHT...FROM AROUND 03Z AND LATER. FORECAST SOUNDINGS ESPECIALLY FROM THE GFS SUGGEST A FEW WIND GUSTS INTO THE TEENS KNOTS WITH INITIAL MIXING THIS MORNING...BUT THE TREND OF ANY GUSTINESS SHOULD DIMINISH BY EARLY AFTERNOON AS THE SURFACE HIGH CONTINUES TO BUILD IN. RAP SOUNDINGS ARE A COUPLE OF KNOTS LIGHTER...SO IT IS POSSIBLE THAT THE TAFS REFLECT GUSTS IN THE TEENS KNOTS THAT ARE ON THE HIGHER END OF WHAT MAY OCCUR WITH MIXING THIS MORNING INTO EARLY AFTERNOON...ESPECIALLY TOWARD THE TRIAD. LIGHT SOUTH TO SOUTHWEST WIND BY THIS EVENING. BEYOND THE 12Z VALID TAF PERIOD...VFR SUNDAY...WITH AN INCREASING POSSIBILITY OF MVFR CLOUDS DURING THE AFTERNOON...THEN SUB-VFR CONDITIONS AND AREAS OF RAIN LIKELY OVERNIGHT SUNDAY AHEAD OF A COLD FRONT THAT WILL MOVE THROUGH CENTRAL NORTH CAROLINA EARLY MONDAY. AHEAD OF THE COLD FRONT SUNDAY NIGHT...WINDS ALOFT WILL INCREASE TO SOUTHWEST AOA 50KT BY 2500FT. VFR CONDITIONS RETURN BY MONDAY AFTERNOON WITH GUSTY WEST-NORTHWEST AND NORTHWEST SURFACE WINDS. VFR CONDITIONS SHOULD THEN CONTINUE THROUGH WEDNESDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...DJF NEAR TERM...DJF SHORT TERM...CBL LONG TERM...DJF AVIATION...DJF
AREA FORECAST DISCUSSION
NWS BISMARCK ND
252 PM CST SAT JAN 31 2015 .SHORT TERM...(THIS EVENING THROUGH SUNDAY) ISSUED AT 245 PM CST SAT JAN 31 2015 .SHORT TERM...TONIGHT AND SUNDAY... MAIN ISSUED THIS FORECAST PERIOD WILL BE SNOW POTENTIAL THIS AFTERNOON AND EVENING. SNOW IS STILL FORECAST TO REMAIN BELOW ADVISORY CRITERIA WITH FAIRLY WIDESPREAD SNOW AMOUNTS OF 3 INCHES ACROSS WEST CENTRAL ND THIS AFTERNOON WITH 2 TO 3 INCHES SPREADING INTO THE SOUTH CENTRAL TONIGHT. AN ISOLATED 4 INCH AMOUNT IS POSSIBLE BUT NOT WIDESPREAD. THEN WIND CHILLS BECOME A CONCERN ACROSS THE NORTH CENTRAL THROUGH THE NORTHERN JAMES RIVER VALLEY TONIGHT INTO SUNDAY MORNING. LATEST RADAR TRENDS SHOW THE SNOW THIS AFTERNOON IS CONCENTRATED ACROSS THE WEST CENTRAL WHERE UP TO 3 INCHES MAY FALL BY EARLY EVENING. THEN THIS EVENING THEN SNOW WILL BE FOCUSED ALONG AN H300 JET REGION WHICH EXTENDS NORTHEAST TO SOUTHWEST ACROSS WESTERN NORTH DAKOTA. THE LATEST HRRR RUNS FOLLOW THE JET DYNAMICS AND FORM A SNOW BAND THAT EXTENDS FROM SOUTHWEST NORTH DAKOTA INTO THE SOUTH CENTRAL BETWEEN 00Z-06Z. BELIEVE THERE WILL ANOTHER 3 INCH BAND OF SNOW FROM BOWMAN NORTHEAST TO BISMARCK. THE MOST RAPIDLY CHANGING WEATHER WILL BE FOUND SOUTH CENTRAL WHERE THE PARTLY SUNNY SKIES THIS AFTERNOON WILL QUICKLY CHANGE TO SNOW. BUFKIT SOUNDINGS FROM DICKINSON TO BISMARCK THIS EVENING SHOW A FAIRLY DEEP DENDRITIC GROWTH ZONE WITH SUPER SATURATION WITH RESPECT TO ICE. THUS THERE WILL BE GOOD SNOW POTENTIAL FROM THE LIMITED QPF THAT HAS BEEN CONSISTENTLY FORECAST FOR THIS SYSTEM. THIS EVENING...WILL ISSUE A WIND CHILL ADVISORY FOR WIND CHILLS 25 TO 30 BELOW EXTENDING FROM BOTTINEAU COUNTY SOUTHEAST THROUGH STUTSMAN COUNTY. TOWNS INCLUDED IN THIS AREA INCLUDE BOTTINEAU...RUGBY... HARVEY AND JAMESTOWN. BY SUNDAY MORNING THE SNOW WILL END. SHOULD SEE CONSIDERABLE SUNSHINE BOT COLD TEMPERATURES SUNDAY .LONG TERM...(SUNDAY NIGHT THROUGH SATURDAY) ISSUED AT 245 PM CST SAT JAN 31 2015 THE PATTERN REMAINS UNSETTLED FOR THE EARLY AND LATTER PORTIONS OF THE LONG TERM PERIOD. SHORTWAVE TROUGHS CONTINUE TO CIRCULATE AROUND THE HUDSON BAY LOW AND INTO NORTH DAKOTA. ALTHOUGH THERE APPEARS TO BE A BREAK WEDNESDAY INTO EARLY FRIDAY...BOTH THE GFS AND ECMWF ARE HINTING AT ANOTHER SYSTEM FRIDAY NIGHT THROUGH SATURDAY. SUNDAY NIGHT AND MONDAY...NOT A LOT OF CHANGE FROM PREVIOUS RUNS AND THOUGHTS AS THIS WILL BE A BRIEF/MINOR WARM AIR ADVECTION PRECIPITATION EVENT MONDAY. SOUTHWEST WINDS SUNDAY NIGHT WILL QUICKLY SHIFT TO THE NORTHWEST DURING THE MORNING IN THE WEST AND AFTERNOON IN THE CENTRAL AS COLD AIR ADVECTION AGAIN TAKES CONTROL. PER NAM/GFS BUFKIT SOUNDINGS...HAVE TEMPERED HIGHS IN THE SOUTHWEST AS COLD AIR ADVECTION TAKES OVER BY MID TO LATE MORNING AND BASICALLY PUTS A CAP ON RISING TEMPERATURES. SNOWFALL POTENTIAL REMAINS LIGHT WITH AROUND A HALF INCH ALONG AND WEST OF THE MISSOURI RIVER. FOR TUESDAY...IT APPEARS THE STRONGER BAROCLINIC ZONE ASSOCIATED WITH AN ARCTIC INTRUSION REMAINS IN SOUTH CENTRAL MONTANA AND WESTERN SOUTH DAKOTA. THE GFS HAS SHIFTED THE MAIN SNOW AXIS ACROSS THE FAR SOUTHWEST. THE NAM/ECMWF ALSO INDICATE A WEAKER SCENARIO BUT HAVE THIS AREA FARTHER EAST AS WELL. QPF TODAY VERSUS THE LAST FEW RUNS HAVE LOWERED QUITE A BIT. SNOWFALL ACCUMULATIONS ARE NOW MORE LIKELY TO RANGE FROM 1 TO 1.5 INCHES ACROSS WESTERN AND SOUTH CENTRAL NORTH DAKOTA. WEDNESDAY THROUGH SATURDAY...MAINLY DRY CONDITIONS CAN BE EXPECTED AS NORTHWEST FLOW CONTINUES WEDNESDAY WITH ARCTIC AIR AND SURFACE HIGH PRESSURE DOMINATING. HIGHS WILL RANGE FROM AROUND ZERO IN THE TURTLE MOUNTAINS TO 20 DEGREES ABOVE ZERO IN THE SOUTHWEST. WARM AIR ADVECTION ONCE AGAIN COMMENCES THURSDAY AND FRIDAY. AN ALBERTA CLIPPER WITH A FAIRLY TIGHT BAROCLINIC ZONE IS FORECAST TO DEVELOP ACROSS CENTRAL AND NORTHERN NORTH DAKOTA FRIDAY THROUGH SATURDAY. THE ECMWF IS MUCH COLDER AS THE BAROCLINIC ZONE SAGS FURTHER SOUTH. BOTH MODELS DEPICT DECENT PRECIPITATION DEVELOPING DURING THIS PERIOD AND SNOW WOULD BE THE LIKELY CANDIDATE IN THE NORTH. THERE IS A POTENTIAL FOR A WINTRY MIX IN/AROUND THE WARMER SIDE OF THE BAROCLINIC ZONE. WILL NEED TO MONITOR THIS IN THE COMING DAYS. HIGH TEMPERATURES FRIDAY/SATURDAY WILL DEPEND ON WHERE THE BAROCLINIC ZONE SETS UP ACROSS SOUTHWEST/NORTHERN NORTH DAKOTA. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 245 PM CST SAT JAN 31 2015 HAZARDS TO AVIATION INCLUDE IFR CONDITIONS IN CLOUDS AND SNOW FROM SURFACE TROUGH OF LOW PRESSURE FORECAST TO MOVE FROM EASTERN MONTANA THROUGH CENTRAL NORTH DAKOTA TONIGHT. THIS WILL IMPACT KISN-KDIK-KMOT THIS AFTERNOON...AND KDIK-KBIS TONIGHT. ARCTIC HIGH PRESSURE WILL MOVE SOUTH FROM SASKATCHEWAN AND MANITOBA SUNDAY BRINGING IMPROVING CONDITIONS TO VFR MOST AREA AFTER SUNRISE SUNDAY. LOWER CLOUDS MAY LINGER LONGER AT KDIK. && .BIS WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 10 AM CST SUNDAY FOR NDZ004-005-012- 013-022-023-025-036-037. && $$ SHORT TERM...WAA LONG TERM...KS AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1208 PM CST SAT JAN 31 2015 .UPDATE... ISSUED AT 1201 PM CST SAT JAN 31 2015 DRY SLOT ACROSS SOUTH CENTRAL NORTH DAKOTA CAUSING SOME MAJOR REVISIONS IN THE SKY GRIDS AS A BIG CLEAR HOLE HAS OPENED UP SOUTH CENTRAL AS DRY NORTHEAST FLOW BRINGING IN LOW LEVEL DRY AIR. SNOW SPREADING ACROSS THE NORTH AND WEST...AND WILL EVENTUALLY REACH THE SOUTH CENTRAL THIS EVENING. UPDATE ISSUED AT 936 AM CST SAT JAN 31 2015 LATEST BUFKIT MODEL ANALYSIS FOR THE NAM SHOW A FAIRLY DEEP DENDRITIC GROWTH ZONE LATE THIS AFTERNOON AND TONIGHT ACROSS WESTERN NORTH DAKOTA. WITH SUPERSATURATION WITH RESPECT TO ICE THE LOWER ATMOSPHERE SHOULD MAXIMIZE ITS POTENTIAL FOR CREATING SNOW. MODELS STILL HAVE MODEST QPF AMOUNTS. (THE LATEST HRRR QPF THROUGH 04Z HAS BETWEEN 0.15-0.25). BELIEVE SNOW AMOUNTS OF 3 INCHES OVERALL WITH ISOLATED HIGHER AMOUNTS STILL LOOK GOOD. CURRENT FORECAST LOOKS ON TRACK. UPDATE ISSUED AT 637 AM CST SAT JAN 31 2015 NO MAJOR CHANGES TO THE GOING FORECAST. LIGHT SNOW IS DEVELOPING ACROSS THE NORTHERN TIER COUNTIES THIS MORNING AND WILL SPREAD SOUTH AND EAST THROUGH THE DAY. DID EXTEND THE MENTION OF FOG THROUGH 15 UTC ACROSS THE SOUTHWEST AND FAR SOUTH CENTRAL. UPDATED TEXT WILL BE OUT SHORTLY && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 343 AM CST SAT JAN 31 2015 THE MAIN FOCUS FOR THE SHORT TERM IS ACCUMULATING SNOW TODAY/TONIGHT. A SHORTWAVE TROUGH CURRENTLY OVER SOUTHERN ALBERTA AND AN INVERTED SURFACE TROUGH...CURRENTLY CENTERED ACROSS EASTERN MONTANA...WILL SLOWLY PROPAGATE SOUTHEAST THROUGH THE MORNING HOURS. AS IT DOES WIDESPREAD SNOW ACROSS SOUTHERN CANADA IS EXPECTED TO CONTINUE TO DEVELOP AND ENTER NORTHWESTERN NORTH DAKOTA. A DEFORMATION ZONE IS EXPECTED TO SET UP ACROSS WESTERN NORTH DAKOTA LATER THIS MORNING AS A SHORTWAVE TROUGH OVER THE FOUR CORNERS INTERACTS WITH THE ALBERTA SHORTWAVE. 00 UTC MODELS ARE IN GOOD AGREEMENT ON TIMING AND LOCATION OF THE SNOW. BY 6AM A LIGHT SNOW BAND SHOULD BEGIN OVERSPREADING NORTHWESTERN NORTH DAKOTA. THIS BAND IS EXPECTED TO SLIDE SLOWLY SOUTH THROUGH THE DAY. THE ECMWF/NAM/SREF/GFS ALL HAVE THE HEAVIEST QPF AMOUNTS ACROSS WEST CENTRAL NORTH DAKOTA DURING THE AFTERNOON HOURS. FOR THE FORECAST WENT WITH A BLEND OF THE OPERATIONAL MODELS WHICH ENDS UP PRODUCING WIDESPREAD 2 TO 3 INCHES OF SNOW ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH HEAVIEST AMOUNTS WEST OF HIGHWAY 83. TEMPERATURES WILL CONTINUE TO GRADUALLY FALL THROUGH THE DAY WITH CLOUDY SKIES LIMITING SOLAR INSULATION AND COLD AIR ADVECTION CONTINUES IN FULL FORCE. TEMPERATURES WILL LIKELY FALL BELOW ZERO ACROSS THE JAMES VALLEY TONIGHT. WIND CHILL READINGS WILL NEAR 20 BELOW BY THE EARLY MORNING HOURS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 343 AM CST SAT JAN 31 2015 MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD. DETERMINISTIC MODELS ARE IN QUITE GOOD AGREEMENT THROUGH MOST OF THE EXTENDED PERIOD AND USED A MODEL BLEND FOR FORECAST DETAILS. WE BEGIN THE PERIOD SUNDAY WITH A 1040 MB SURFACE HIGH DROPPING FROM SOUTHERN CANADA INTO CENTRAL NORTH DAKOTA BY 18 UTC SUNDAY. LIGHT SNOWS FROM THE EXITING SHORT TERM SYSTEM SHOULD BE ALL BUT OUT OF THE SOUTHERN CWA BY 18 UTC...BUT DID INCLUDE A SLIGHT CHANCE OF LIGHT SNOW WITH OVER THE FAR SOUTH CENTRAL AS REMNANTS MOVE OUT OF THE FORECAST AREA SUNDAY MORNING. OTHERWISE DRY BUT COLD SUNDAY. WIND CHILL HIGHLIGHTS MAY BE NEEDED SUNDAY MORNING IF CURRENT TRENDS HOLD...OVER THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY. AS THE SURFACE HIGH SLIDES SOUTHEAST SUNDAY NIGHT WARM ADVECTION RETURNS TO WESTERN NORTH DAKOTA. BY MONDAY MORNING...UPPER LEVEL FORCING WITH A 120KT JET INDUCES A SURFACE LOW PRESSURE CENTER OVER SOUTHEAST MONTANA THAT TRACKS SOUTHEAST ACROSS INTO CENTRAL SOUTH DAKOTA. THE GFS IS THE WEAKEST AND FARTHEST SOUTH WITH THE SURFACE LOW AND BRINGS VERY LIGHT SNOW AMOUNTS INTO THE FAR SOUTHWEST. ALL OTHER DETERMINISTIC MODELS TRACK THE SURFACE LOW IN A FAVORED POSITION TO BRING LIGHT SNOWS TO WESTERN AND SOUTH CENTRAL NORTH DAKOTA. AMOUNTS HERE ARE DEFINITELY SUB-ADVISORY CRITERIA AND AS A FIRST GUESS HAVE GONE WITH HALF INCH TO ONE INCH AMOUNTS ALONG AND SOUTH OF LAKE SAKAKAWEA AND THE MISSOURI RIVER...WITH LITTLE OR NO ACCUMULATIONS NORTH AND EAST OF HERE. TAKING THE GFS OUT OF THE BLEND WOULD YIELD HIGHER AMOUNTS...MAYBE 1-2 INCHES IN THIS SAME GENERAL AREA...SO WILL HAVE TO MONITOR...BUT STILL SUB-ADVISORY SNOWS. ANOTHER IMPULSE QUICKLY RACES INTO THE AREA ALREADY BY LATE MONDAY NIGHT. THIS TIME THERE IS A TIGHTER BAROCLINIC ZONE THAT IMPULSES WILL INTERACT WITH OVER THE SAME GENERAL AREA OF WESTERN INTO SOUTH CENTRAL NORTH DAKOTA. THERE ARE SOME MODEL DIFFERENCES IN THE PLACEMENT OF THE SURFACE AND UPPER LEVEL FEATURES BUT MODELS ARE CURRENTLY IN GOOD AGREEMENT IN BRINGING ANOTHER SWATH OF LIGHT SNOWS OVER WESTERN AND SOUTH CENTRAL NORTH DAKOTA...WITH THE TURTLE MOUNTAINS AREA ONCE AGAIN SEEING THE THE SMALLEST CHANCES OF ACCUMULATING SNOWS. IN GENERAL...WE ARE TALKING SUB-ADVISORY CRITERIA SNOWS OF 1 TO 3 INCHES LATE MONDAY NIGHT THROUGH TUESDAY. THE GFS IS A LITTLE MORE IMPRESSIVE WITH THE SURFACE LOW AND HINTS AT SOME INDIRECT JET CIRCULATION BETWEEN THE TWO STRONG JETLETS OVER THE NORTHERN PLAINS. THUS WILL NEED TO KEEP AN EYE ON THIS SYSTEM AS WELL. ONE LAST IMPULSE KEEPS A LINGERING CHANCE OF LIGHT SNOW OVER THE SOUTHWEST THROUGH TUESDAY EVENING...THEN ARCTIC HIGH PRESSURE DROPS INTO THE AREA AND PUTS AN END TO THE SNOW CHANCES BY LATE TUESDAY NIGHT. HOWEVER...WIND CHILLS WILL LIKELY AGAIN BE AN ISSUE OVER MAINLY THE NORTHERN THIRD OF THE FORECAST AREA. WE THEN WARM UP QUICKLY THURSDAY AS THE ARCTIC HIGH DIVES QUICKLY SOUTH AND EAST. WE TRANSITION TO A MORE QUASI-ZONAL FLOW WITH SHORTWAVES TRAVERSING THE AREA FRIDAY AND SATURDAY. WITH THE WARMER TEMPERATURES WE MAY NEED TO WORRY MORE ABOUT POSSIBLE MIXED PRECIPITATION BUT TEMPERATURES WILL BE BACK ABOVE NORMAL. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SUNDAY AFTERNOON) ISSUED AT 1201 PM CST SAT JAN 31 2015 MAIN HAZARD TO AVIATION FOR THE 18Z FORECAST INCLUDES IFR CONDITIONS IN CLOUDS AND SNOW. SURFACE TROUGH OF LOW PRESSURE ACROSS EASTERN MONTANA WILL MOVE SOUTHEAST TODAY AND TONIGHT. EXPECT DETERIORATING CONDITIONS FROM WEST TO EAST A A LARGE SNOW REGION MOVES FROM WESTERN INTO CENTRAL NORTH DAKOTA THIS AFTERNOON AND TONIGHT. ARCTIC HIGH PRESSURE WILL NOSE IN FROM SASKATCHEWAN TONIGHT AND SUNDAY BRINGING IMPROVING CONDITIONS AFTER 12Z NORTH AND EAST. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...AJ LONG TERM...TWH AVIATION...WAA
AREA FORECAST DISCUSSION
NWS BISMARCK ND
951 AM CST SAT JAN 31 2015 .UPDATE... ISSUED AT 936 AM CST SAT JAN 31 2015 LATEST BUFKIT MODEL ANALYSIS FOR THE NAM SHOW A FAIRLY DEEP DENDRITIC GROWTH ZONE LATE THIS AFTERNOON AND TONIGHT ACROSS WESTERN NORTH DAKOTA. WITH SUPERSATURATION WITH RESPECT TO ICE THE LOWER ATMOSPHERE SHOULD MAXIMIZE ITS POTENTIAL FOR CREATING SNOW. MODELS STILL HAVE MODEST QPF AMOUNTS. (THE LATEST HRRR QPF THROUGH 04Z HAS BETWEEN 0.15-0.25). BELIEVE SNOW AMOUNTS OF 3 INCHES OVERALL WITH ISOLATED HIGHER AMOUNTS STILL LOOK GOOD. CURRENT FORECAST LOOKS ON TRACK. UPDATE ISSUED AT 637 AM CST SAT JAN 31 2015 NO MAJOR CHANGES TO THE GOING FORECAST. LIGHT SNOW IS DEVELOPING ACROSS THE NORTHERN TIER COUNTIES THIS MORNING AND WILL SPREAD SOUTH AND EAST THROUGH THE DAY. DID EXTEND THE MENTION OF FOG THROUGH 15 UTC ACROSS THE SOUTHWEST AND FAR SOUTH CENTRAL. UPDATED TEXT WILL BE OUT SHORTLY && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 343 AM CST SAT JAN 31 2015 THE MAIN FOCUS FOR THE SHORT TERM IS ACCUMULATING SNOW TODAY/TONIGHT. A SHORTWAVE TROUGH CURRENTLY OVER SOUTHERN ALBERTA AND AN INVERTED SURFACE TROUGH...CURRENTLY CENTERED ACROSS EASTERN MONTANA...WILL SLOWLY PROPAGATE SOUTHEAST THROUGH THE MORNING HOURS. AS IT DOES WIDESPREAD SNOW ACROSS SOUTHERN CANADA IS EXPECTED TO CONTINUE TO DEVELOP AND ENTER NORTHWESTERN NORTH DAKOTA. A DEFORMATION ZONE IS EXPECTED TO SET UP ACROSS WESTERN NORTH DAKOTA LATER THIS MORNING AS A SHORTWAVE TROUGH OVER THE FOUR CORNERS INTERACTS WITH THE ALBERTA SHORTWAVE. 00 UTC MODELS ARE IN GOOD AGREEMENT ON TIMING AND LOCATION OF THE SNOW. BY 6AM A LIGHT SNOW BAND SHOULD BEGIN OVERSPREADING NORTHWESTERN NORTH DAKOTA. THIS BAND IS EXPECTED TO SLIDE SLOWLY SOUTH THROUGH THE DAY. THE ECMWF/NAM/SREF/GFS ALL HAVE THE HEAVIEST QPF AMOUNTS ACROSS WEST CENTRAL NORTH DAKOTA DURING THE AFTERNOON HOURS. FOR THE FORECAST WENT WITH A BLEND OF THE OPERATIONAL MODELS WHICH ENDS UP PRODUCING WIDESPREAD 2 TO 3 INCHES OF SNOW ACROSS WESTERN AND CENTRAL NORTH DAKOTA...WITH HEAVIEST AMOUNTS WEST OF HIGHWAY 83. TEMPERATURES WILL CONTINUE TO GRADUALLY FALL THROUGH THE DAY WITH CLOUDY SKIES LIMITING SOLAR INSULATION AND COLD AIR ADVECTION CONTINUES IN FULL FORCE. TEMPERATURES WILL LIKELY FALL BELOW ZERO ACROSS THE JAMES VALLEY TONIGHT. WIND CHILL READINGS WILL NEAR 20 BELOW BY THE EARLY MORNING HOURS. .LONG TERM...(SUNDAY THROUGH FRIDAY) ISSUED AT 343 AM CST SAT JAN 31 2015 MAIN FORECAST HIGHLIGHTS ARE COLD AND UNSETTLED WEATHER THROUGH AT LEAST MID WEEK WITH A NUMBER OF LIGHT SNOW EVENTS. THEN POSSIBLY A RETURN TO MORE MILD CONDITIONS AT THE END OF THE EXTENDED PERIOD. DETERMINISTIC MODELS ARE IN QUITE GOOD AGREEMENT THROUGH MOST OF THE EXTENDED PERIOD AND USED A MODEL BLEND FOR FORECAST DETAILS. WE BEGIN THE PERIOD SUNDAY WITH A 1040 MB SURFACE HIGH DROPPING FROM SOUTHERN CANADA INTO CENTRAL NORTH DAKOTA BY 18 UTC SUNDAY. LIGHT SNOWS FROM THE EXITING SHORT TERM SYSTEM SHOULD BE ALL BUT OUT OF THE SOUTHERN CWA BY 18 UTC...BUT DID INCLUDE A SLIGHT CHANCE OF LIGHT SNOW WITH OVER THE FAR SOUTH CENTRAL AS REMNANTS MOVE OUT OF THE FORECAST AREA SUNDAY MORNING. OTHERWISE DRY BUT COLD SUNDAY. WIND CHILL HIGHLIGHTS MAY BE NEEDED SUNDAY MORNING IF CURRENT TRENDS HOLD...OVER THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY. AS THE SURFACE HIGH SLIDES SOUTHEAST SUNDAY NIGHT WARM ADVECTION RETURNS TO WESTERN NORTH DAKOTA. BY MONDAY MORNING...UPPER LEVEL FORCING WITH A 120KT JET INDUCES A SURFACE LOW PRESSURE CENTER OVER SOUTHEAST MONTANA THAT TRACKS SOUTHEAST ACROSS INTO CENTRAL SOUTH DAKOTA. THE GFS IS THE WEAKEST AND FARTHEST SOUTH WITH THE SURFACE LOW AND BRINGS VERY LIGHT SNOW AMOUNTS INTO THE FAR SOUTHWEST. ALL OTHER DETERMINISTIC MODELS TRACK THE SURFACE LOW IN A FAVORED POSITION TO BRING LIGHT SNOWS TO WESTERN AND SOUTH CENTRAL NORTH DAKOTA. AMOUNTS HERE ARE DEFINITELY SUB-ADVISORY CRITERIA AND AS A FIRST GUESS HAVE GONE WITH HALF INCH TO ONE INCH AMOUNTS ALONG AND SOUTH OF LAKE SAKAKAWEA AND THE MISSOURI RIVER...WITH LITTLE OR NO ACCUMULATIONS NORTH AND EAST OF HERE. TAKING THE GFS OUT OF THE BLEND WOULD YIELD HIGHER AMOUNTS...MAYBE 1-2 INCHES IN THIS SAME GENERAL AREA...SO WILL HAVE TO MONITOR...BUT STILL SUB-ADVISORY SNOWS. ANOTHER IMPULSE QUICKLY RACES INTO THE AREA ALREADY BY LATE MONDAY NIGHT. THIS TIME THERE IS A TIGHTER BAROCLINIC ZONE THAT IMPULSES WILL INTERACT WITH OVER THE SAME GENERAL AREA OF WESTERN INTO SOUTH CENTRAL NORTH DAKOTA. THERE ARE SOME MODEL DIFFERENCES IN THE PLACEMENT OF THE SURFACE AND UPPER LEVEL FEATURES BUT MODELS ARE CURRENTLY IN GOOD AGREEMENT IN BRINGING ANOTHER SWATH OF LIGHT SNOWS OVER WESTERN AND SOUTH CENTRAL NORTH DAKOTA...WITH THE TURTLE MOUNTAINS AREA ONCE AGAIN SEEING THE THE SMALLEST CHANCES OF ACCUMULATING SNOWS. IN GENERAL...WE ARE TALKING SUB-ADVISORY CRITERIA SNOWS OF 1 TO 3 INCHES LATE MONDAY NIGHT THROUGH TUESDAY. THE GFS IS A LITTLE MORE IMPRESSIVE WITH THE SURFACE LOW AND HINTS AT SOME INDIRECT JET CIRCULATION BETWEEN THE TWO STRONG JETLETS OVER THE NORTHERN PLAINS. THUS WILL NEED TO KEEP AN EYE ON THIS SYSTEM AS WELL. ONE LAST IMPULSE KEEPS A LINGERING CHANCE OF LIGHT SNOW OVER THE SOUTHWEST THROUGH TUESDAY EVENING...THEN ARCTIC HIGH PRESSURE DROPS INTO THE AREA AND PUTS AN END TO THE SNOW CHANCES BY LATE TUESDAY NIGHT. HOWEVER...WIND CHILLS WILL LIKELY AGAIN BE AN ISSUE OVER MAINLY THE NORTHERN THIRD OF THE FORECAST AREA. WE THEN WARM UP QUICKLY THURSDAY AS THE ARCTIC HIGH DIVES QUICKLY SOUTH AND EAST. WE TRANSITION TO A MORE QUASI-ZONAL FLOW WITH SHORTWAVES TRAVERSING THE AREA FRIDAY AND SATURDAY. WITH THE WARMER TEMPERATURES WE MAY NEED TO WORRY MORE ABOUT POSSIBLE MIXED PRECIPITATION BUT TEMPERATURES WILL BE BACK ABOVE NORMAL. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SUNDAY MORNING) ISSUED AT 637 AM CST SAT JAN 31 2015 MVFR TO IFR CIGS WILL CONTINUE OVER THE AREA THROUGH THE FORECAST PERIOD. SNOW HAS DEVELOPED IN THE FAR NORTH AND WILL SPREAD SOUTH AND EAST ACROSS ALL AERODROMES THROUGH THE DAY. AREAS OF DENSE FOG SOUTHWEST INCLUDING KDIK SHOULD LIFT BY AROUND 15 UTC. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...AJ LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
918 PM EST SUN FEB 1 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE UP THE OHIO VALLEY TONIGHT...AND CROSS THE STATE ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION ACROSS THE AREA INTO MONDAY MORNING. A PERIOD OF FREEZING RAIN IS LIKELY ACROSS THE SOUTHERN AND CENTRAL SECTIONS OF THE STATE OVERNIGHT. ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO TUESDAY...WITH LOW WIND CHILLS TUESDAY MORNING. A COLD FRONT MOVING THROUGH WEDNESDAY WILL BE ACCOMPANIED BY SOME LIGHT SNOW...MAINLY IN THE NORTHWESTERN HALF OF THE STATE. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... BANDS OF MODERATE TO HEAVY SNOW MOVED QUICKLY ACROSS THE REGION INTO NORTHERN PA AS OF EARLY EVENING. MORE BANDS MOVING INTO THE AREA FROM THE WEST AS OF 9 PM. SATELLITE PICS SHOW COOLING TOPS OVER DE...NJ...AND FAR SE PA. HOWEVER...TOPS STILL COOLING TO THE WEST OVER LAKE ERIE TO SW OH WITH THE LOW FROM THE MIDWEST. 12Z MODELS SHOW HEAVIEST QPF LIFTING ACROSS THE NW INTO THE EARLY MORNING HOURS. SO FAR ALL SNOW...BUT EXPECT SOME LIGHT FREEZING RAIN LATE ACROSS THE SOUTH...AS WARMER AIR ALOFT WORKS IN...AND THE INTENSITY RATES DECREASE LATE. THE PRECIPITATION COULD GO TO ALL RAIN LATE ACROSS THE FAR SOUTH...AS TEMPS CLIMB SOME LATE. THUS WILL LEAVE CURRENT WARNINGS AND ADVISORIES UP. EXPECT GUSTY WINDS AND COLDER AIR TO WORK IN AFTER SUNRISE ON MONDAY...BUT EXCEPT FOR THE FAR NW AND WEST...MOST OF THE PRECIPITATION WILL BE EAST OF THE AREA BY THE TIME TEMPS FALL BACK. 206 PM DISCUSSION BELOW. PRETTY SOLID BAND OF WAA SNOW IS PUSHING THROUGH WRN PA BUT NOT MUCH BEHIND IT. MESO MODELS HAVE BEEN PLAYING THAT BREAK UP FOR A LITTLE WHILE...AND IT LOOKS LIKE IT IS COMING TO FRUITION. THIS WILL YIELD A 3-4 HOUR BREAK IN THE SNOW FOR MOST PLACES. WHILE IT HAS BEEN SNOWING ALL DAY OUT THE WINDOW...IT STILL REALLY HAS NOT STARTED STICKING TO ANYTHING. THIS APPEARS TO BE THE CASE ALMOST EVERYWHERE IN THE CWA JUDGING BY WEB CAMS. BUT THE HIGHER ELEVS OF THE LAURELS SHOULD BE GETTING WHITE ANY TIME NOW. WILL JUST WORK THE POPS AROUND TO TRY TO SHOW THAT LITTLE BREAK...BUT IT IS SUCH A SMALL-SCALE FEATURE THAT IT MAY JUST END UP WASHING OUT IN THE BIGGER PICTURE. TEMPS DANCING AROUND 32F IN THE CENTRAL COS BUT WELL INTO THE M30S IN THE SE. PRECIP THERE WILL BE VERY LIGHT UNTIL MUCH LATER/THIS EVENING. SO...P-TYPE WILL BE DIFFICULT TO PIN DOWN. CERTAINLY IF IT DECIDES TO SNOW HEAVILY...IT WILL BE SNOW FOR THAT TIME...BUT WILL LIKELY BE A MIX WHEN LIGHT IN THE S/SE. TEMPS MOVE LITTLE ALL EVENING...BUT WILL PROBABLY COOL JUST A LITTLE WITH WET BULBING. DEWPOINTS ALREADY RISING SOME LOCALLY. && .SHORT TERM /6 AM MONDAY MORNING THROUGH 6 PM MONDAY/... THE BEST PERIOD OF SNOW CONTINUES TO LOOK LIKE IT WILL BE BETWEEN 00-09Z WITH THE WORST OF IT ACROSS THE NRN HALF OF THE AREA. THE WARM AIR ALOFT LOOKS TO MAKE IN-ROADS ALL THE WAY TO I-80 BY SUNRISE MONDAY. THUS...THE ICING POTENTIAL IS STILL THERE. SO WHILE THE SNOW AMOUNTS - ESPECIALLY IF YOU ONLY MEASURE IN THE MORNING - WILL BE LOWER THAN PREVIOUSLY ADVERTISED IN THE SRN HALF OF THE AREA...THERE IS STILL SOME /WEAK/ JUSTIFICATION FOR HOLDING ONTO THE WARNING ALONG THE RTE 22 CORRIDOR...FOR NOW. THE QPF IS A MIXED-BAG OF SIGNALS RIGHT NOW. GFS AND EURO ARE HOLDING ONTO 0.80 OR MORE IN THE NRN HALF OF THE AREA...WITH ONLY REAL SNOW THERE. THE NAM AND THE SREF MEAN TOTALS THERE ARE ONLY ABOUT 0.50. WILL CONTINUE WITH THE PARTY LINE OF 8-10 FOR A STORM TOTAL...BUT REWORKED THE NUMBERS DOWN BARELY AN INCH ON THE WHOLE SO THE TERRIBLE DARK BLUE OF 10-14 DOES NOT HIT PEOPLE IN THE FACE. AGAIN...JUST HALF AN INCH TO AN INCH OF A DOWNWARD MOVE ON THE SNOW. THIS IS DUE TO THE RELATIVELY HIGH UNCERTAINTY AT THIS RANGE. STILL LOOKS LIKE A SOLID WARNING ANY WAY YOU SLICE IT UP FOR OUR ENTIRE NRN HALF. SOME PRETTY WICKED SF RATES WILL BE HAD OVERNIGHT AND VERY EARLY MONDAY IN THE NORTH AND PERHAPS AS FAR S AS STATE COLLEGE AND SUNBURY BUT MOST LIKELY - THE HEAVIEST SNOW WILL BE JUST TO THE NORTH OF THOSE TWO CITIES. PRECIP CUTS OFF PRETTY QUICKLY AFTER 12Z/14Z IN THE CENTRAL COS. THE EAST MAY SEE PRECIP LINGER INTO THE MID MORNING AS THE COLD AIR MOVES IN AND TEMPS DROP. AFTER WHAT MAY ONLY BE A BRIEF BREAK...THE NW WINDS WILL UPSLOPE INTO THE ALLEGHENIES AND LAURELS. CAA WILL CREATE NUMEROUS SHSN OVER THE WRN HIGH TERRAIN AND FLURRIES ELSEWHERE. THERE MAY EVEN BE SOME DECENT SHSN AS THE PRECIP ENDS IN THE SERN THIRD OF THE AREA. YET ANOTHER REASON TO NOT MONKEY WITH THE WARNINGS/ADVYS JUST YET. IT COULD BE A MESSY COMMUTE FOR GROUNDHOG MORNING. WINDS WILL GET STRONG AND RATHER GUSTY - ESP ON THE HILL TOPS AND IN THE SERN THIRD/DOWNSLOPE AREAS CLOSEST TO THE DEEPENING LOW MOVING OFF THE COAST. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND LAUREL HIGHLANDS POSSIBLY NEEDING A WIND CHILL ADVISORY /-15F/ MON NIGHT INTO EARLY TUE. ENSEMBLE MEAN 5H PATTERN SHOWS AN ALBERTA CLIPPER DIVING SE INTO THE REGION WED/THU. ALL MED RANGE GUIDANCE TRACKS ASSOC SFC LOW NORTH OF THE STATE EARLY WED...LIKELY PRODUCING A BIT OF LGT SNOW ACROSS NORTHERN PA. A WEAK LOW ON TRAILING COLD FRONT COULD SUPPORT SOME LINGERING LGT SNOW ACROSS THE REGION /MAINLY ALLEGHENIES/ INTO EARLY THURSDAY. MODERATING TEMPS AHEAD OF CLIPPER COULD RESULT IN A DAY OF NEAR NORMAL HIGHS WEDNESDAY. HOWEVER...A REINFORCING SHOT OF ARCTIC AIR LOOKS NEARLY CERTAIN BEHIND CLIPPER LATE THIS WEEK. NO RESPITE FROM THE BLW NORMAL TEMPS IN THE EXTENDED...AS LATEST MED RANGE GUIDANCE MAINTAINS UPPER LVL TROF AXIS ACROSS THE NORTHEAST CONUS. && .AVIATION /02Z MONDAY THROUGH FRIDAY/... DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING CIGS ACROSS CENTRAL PA. AT 17Z...IFR CONDS ALREADY NOTED ACROSS WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS IFR CONDS WILL DEVELOP AT KAOO/KUNV/KIPT BTWN 19Z-21Z. ACROSS THE SOUTHEAST COUNTIES...LATEST MDL DATA SUGGESTS A BAND OF LGT SNOW/VIS REDUCTIONS COULD COME THROUGH BTWN 22Z-01Z AT KMDT/KLNS. HOWEVER...CONFIDENCE IN IFR CONDS WILL INCREASE MARKEDLY AT KMDT/KLNS BTWN 03Z-06Z...AS HEAVIEST SNOW ARRIVES. WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT. HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. MARGINAL LLWS REMAINS A POSSIBILITY LATE TONIGHT ACROSS SOUTHERN PA...AS CORE OF STRONG WINDS ALOFT SLIDES ACROSS THE AREA. HOWEVER...LATEST MODEL SOUNDINGS SUGGEST MOST PLACES WILL REMAIN JUST BLW CRITERIA. MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL SHIFT TOWARD STRONG GUSTY WINDS MON PM. GUSTS TO ARND 40KTS ARE POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM PASSES EAST OF PA. OUTLOOK... MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS. TUE...NO SIG WX EXPECTED. WED...AM LGT SNOW POSSIBLE NW MTNS. THU...AM LGT SNOW POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006- 010>012-017>019-037-041-042-045-046-049>053-058. WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036- 064>066. WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056- 057-059-063. && $$ SYNOPSIS...DANGELO NEAR TERM...DANGELO/MARTIN SHORT TERM...DANGELO LONG TERM...FITZGERALD AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
615 PM EST SUN FEB 1 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE UP THE OHIO VALLEY TONIGHT...AND CROSS THE STATE ON MONDAY. THIS WILL PRODUCE WIDESPREAD WINTRY PRECIPITATION ACROSS THE AREA INTO MONDAY MORNING. A PERIOD OF FREEZING RAIN IS LIKELY ACROSS THE SOUTHERN AND CENTRAL SECTIONS OF THE STATE OVERNIGHT. ANOTHER SHOT OF ARCTIC AIR WILL FOLLOW FOR MONDAY AFTERNOON INTO TUESDAY...WITH LOW WIND CHILLS TUESDAY MORNING. A COLD FRONT MOVING THROUGH WEDNESDAY WILL BE ACCOMPANIED BY SOME LIGHT SNOW...MAINLY IN THE NORTHWESTERN HALF OF THE STATE. && .NEAR TERM /UNTIL 11 PM THIS EVENING/... BANDS OF MODERATE TO HEAVY SNOW MOVED QUICKLY ACROSS THE REGION SINCE 3 PM. HEAVIEST BANDS ACROSS THE NORTHERN TIER NOW...BUT WITH LOW TRACKING TOWARD PA...EXPECT MORE HEAVY BANDS THIS EVENING. ACROSS THE SE...JUST A BRIEF PERIOD OF SNOW SO FAR AT LNS. THIS FITS GOOD WITH THE CURRENT PACKAGE. ACROSS THE FAR SOUTH...RADAR RETURNS NOW WEAK...LITTLE SNOW HAS BEEN REPORTED IN THIS AREA. BASED ON THIS AND MODEL DATA...EXPECT SOME PATCHY MIXED PCPN TO START TO MIX IN ACROSS THIS AREA THIS EVENING. WILL KEEP CURRENT WARNINGS AND ADVISORIES FOR NOW. WILL CONTINUE TO MONITOR AND UPDATE AS NEEDED. EARLIER DISCUSSION BELOW. PRETTY SOLID BAND OF WAA SNOW IS PUSHING THROUGH WRN PA BUT NOT MUCH BEHIND IT. MESO MODELS HAVE BEEN PLAYING THAT BREAK UP FOR A LITTLE WHILE...AND IT LOOKS LIKE IT IS COMING TO FRUITION. THIS WILL YIELD A 3-4 HOUR BREAK IN THE SNOW FOR MOST PLACES. WHILE IT HAS BEEN SNOWING ALL DAY OUT THE WINDOW...IT STILL REALLY HAS NOT STARTED STICKING TO ANYTHING. THIS APPEARS TO BE THE CASE ALMOST EVERYWHERE IN THE CWA JUDGING BY WEB CAMS. BUT THE HIGHER ELEVS OF THE LAURELS SHOULD BE GETTING WHITE ANY TIME NOW. WILL JUST WORK THE POPS AROUND TO TRY TO SHOW THAT LITTLE BREAK...BUT IT IS SUCH A SMALL-SCALE FEATURE THAT IT MAY JUST END UP WASHING OUT IN THE BIGGER PICTURE. TEMPS DANCING AROUND 32F IN THE CENTRAL COS BUT WELL INTO THE M30S IN THE SE. PRECIP THERE WILL BE VERY LIGHT UNTIL MUCH LATER/THIS EVENING. SO...P-TYPE WILL BE DIFFICULT TO PIN DOWN. CERTAINLY IF IT DECIDES TO SNOW HEAVILY...IT WILL BE SNOW FOR THAT TIME...BUT WILL LIKELY BE A MIX WHEN LIGHT IN THE S/SE. TEMPS MOVE LITTLE ALL EVENING...BUT WILL PROBABLY COOL JUST A LITTLE WITH WET BULBING. DEWPOINTS ALREADY RISING SOME LOCALLY. && .SHORT TERM /11 PM THIS EVENING THROUGH 6 PM MONDAY/... THE BEST PERIOD OF SNOW CONTINUES TO LOOK LIKE IT WILL BE BETWEEN 00-09Z WITH THE WORST OF IT ACROSS THE NRN HALF OF THE AREA. THE WARM AIR ALOFT LOOKS TO MAKE IN-ROADS ALL THE WAY TO I-80 BY SUNRISE MONDAY. THUS...THE ICING POTENTIAL IS STILL THERE. SO WHILE THE SNOW AMOUNTS - ESPECIALLY IF YOU ONLY MEASURE IN THE MORNING - WILL BE LOWER THAN PREVIOUSLY ADVERTISED IN THE SRN HALF OF THE AREA...THERE IS STILL SOME /WEAK/ JUSTIFICATION FOR HOLDING ONTO THE WARNING ALONG THE RTE 22 CORRIDOR...FOR NOW. THE QPF IS A MIXED-BAG OF SIGNALS RIGHT NOW. GFS AND EURO ARE HOLDING ONTO 0.80 OR MORE IN THE NRN HALF OF THE AREA...WITH ONLY REAL SNOW THERE. THE NAM AND THE SREF MEAN TOTALS THERE ARE ONLY ABOUT 0.50. WILL CONTINUE WITH THE PARTY LINE OF 8-10 FOR A STORM TOTAL...BUT REWORKED THE NUMBERS DOWN BARELY AN INCH ON THE WHOLE SO THE TERRIBLE DARK BLUE OF 10-14 DOES NOT HIT PEOPLE IN THE FACE. AGAIN...JUST HALF AN INCH TO AN INCH OF A DOWNWARD MOVE ON THE SNOW. THIS IS DUE TO THE RELATIVELY HIGH UNCERTAINTY AT THIS RANGE. STILL LOOKS LIKE A SOLID WARNING ANY WAY YOU SLICE IT UP FOR OUR ENTIRE NRN HALF. SOME PRETTY WICKED SF RATES WILL BE HAD OVERNIGHT AND VERY EARLY MONDAY IN THE NORTH AND PERHAPS AS FAR S AS STATE COLLEGE AND SUNBURY BUT MOST LIKELY - THE HEAVIEST SNOW WILL BE JUST TO THE NORTH OF THOSE TWO CITIES. PRECIP CUTS OFF PRETTY QUICKLY AFTER 12Z/14Z IN THE CENTRAL COS. THE EAST MAY SEE PRECIP LINGER INTO THE MID MORNING AS THE COLD AIR MOVES IN AND TEMPS DROP. AFTER WHAT MAY ONLY BE A BRIEF BREAK...THE NW WINDS WILL UPSLOPE INTO THE ALLEGHENIES AND LAURELS. CAA WILL CREATE NUMEROUS SHSN OVER THE WRN HIGH TERRAIN AND FLURRIES ELSEWHERE. THERE MAY EVEN BE SOME DECENT SHSN AS THE PRECIP ENDS IN THE SERN THIRD OF THE AREA. YET ANOTHER REASON TO NOT MONKEY WITH THE WARNINGS/ADVYS JUST YET. IT COULD BE A MESSY COMMUTE FOR GROUNDHOG MORNING. WINDS WILL GET STRONG AND RATHER GUSTY - ESP ON THE HILL TOPS AND IN THE SERN THIRD/DOWNSLOPE AREAS CLOSEST TO THE DEEPENING LOW MOVING OFF THE COAST. && .LONG TERM /MONDAY NIGHT THROUGH SUNDAY/... MAIN IMPACTS FROM WINTER STORM WILL HAVE MOVED AWAY FROM REGION BY MON NIGHT...BUT ARCTIC AIR PUSHING IN WILL BRING A VERY COLD NIGHT WITH LOWS BOTTOMING OUT IN THE SINGLE DIGITS SOUTH AND BELOW ZERO NORTH. THOUGH STRONGER WINDS IN THE EVENING WILL BE GRADUALLY DIMINISHING OVERNIGHT...ENOUGH OF A BREEZE WILL REMAIN TO DROP WIND CHILL VALUES BELOW ZERO FOR ALL...WITH NORTHERN MTNS AND LAUREL HIGHLANDS POSSIBLY NEEDING A WIND CHILL ADVISORY /-15F/ MON NIGHT INTO EARLY TUE. ENSEMBLE MEAN 5H PATTERN SHOWS AN ALBERTA CLIPPER DIVING SE INTO THE REGION WED/THU. ALL MED RANGE GUIDANCE TRACKS ASSOC SFC LOW NORTH OF THE STATE EARLY WED...LIKELY PRODUCING A BIT OF LGT SNOW ACROSS NORTHERN PA. A WEAK LOW ON TRAILING COLD FRONT COULD SUPPORT SOME LINGERING LGT SNOW ACROSS THE REGION /MAINLY ALLEGHENIES/ INTO EARLY THURSDAY. MODERATING TEMPS AHEAD OF CLIPPER COULD RESULT IN A DAY OF NEAR NORMAL HIGHS WEDNESDAY. HOWEVER...A REINFORCING SHOT OF ARCTIC AIR LOOKS NEARLY CERTAIN BEHIND CLIPPER LATE THIS WEEK. NO RESPITE FROM THE BLW NORMAL TEMPS IN THE EXTENDED...AS LATEST MED RANGE GUIDANCE MAINTAINS UPPER LVL TROF AXIS ACROSS THE NORTHEAST CONUS. && .AVIATION /23Z SUNDAY THROUGH FRIDAY/... DETERIORATING FLYING CONDS EXPECTED THIS AFTN AND EVENING...AS LOW PRES APPROACHES FROM THE MIDWEST...SPREADING SNOW AND LOWERING CIGS ACROSS CENTRAL PA. AT 17Z...IFR CONDS ALREADY NOTED ACROSS WESTERN PA. UPSTREAM RADAR RETURNS AND LATEST HRRR OUTPUT SUGGESTS IFR CONDS WILL DEVELOP AT KAOO/KUNV/KIPT BTWN 19Z-21Z. ACROSS THE SOUTHEAST COUNTIES...LATEST MDL DATA SUGGESTS A BAND OF LGT SNOW/VIS REDUCTIONS COULD COME THROUGH BTWN 22Z-01Z AT KMDT/KLNS. HOWEVER...CONFIDENCE IN IFR CONDS WILL INCREASE MARKEDLY AT KMDT/KLNS BTWN 03Z-06Z...AS HEAVIEST SNOW ARRIVES. WARMER AIR WORKING INTO THE STATE WILL CHANGE SNOW TO EITHER RAIN OR FZRA ACROSS THE SOUTHERN HALF OF THE STATE LATE TONIGHT. HOWEVER....WIDESPREAD IFR TO LIFR CONDS EXPECTED EVERYWHERE IN CONTINUING PRECIP AND LOW CIGS RESULTING FROM MOIST SE FLOW ASCENDING THE HIGHER TERRAIN OF CENTRAL PA. MARGINAL LLWS REMAINS A POSSIBILITY LATE TONIGHT ACROSS SOUTHERN PA...AS CORE OF STRONG WINDS ALOFT SLIDES ACROSS THE AREA. HOWEVER...LATEST MODEL SOUNDINGS SUGGEST MOST PLACES WILL REMAIN JUST BLW CRITERIA. MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL SHIFT TOWARD STRONG GUSTY WINDS MON PM. GUSTS TO ARND 40KTS ARE POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM PASSES EAST OF PA. OUTLOOK... MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS. TUE...NO SIG WX EXPECTED. WED...AM LGT SNOW POSSIBLE NW MTNS. THU...AM LGT SNOW POSSIBLE. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST MONDAY FOR PAZ004>006- 010>012-017>019-037-041-042-045-046-049>053-058. WINTER WEATHER ADVISORY UNTIL 8 AM EST MONDAY FOR PAZ033>036- 064>066. WINTER STORM WARNING UNTIL 8 AM EST MONDAY FOR PAZ024>028-056- 057-059-063. && $$ SYNOPSIS...DANGELO NEAR TERM...DANGELO/MARTIN SHORT TERM...DANGELO LONG TERM...FITZGERALD AVIATION...FITZGERALD
AREA FORECAST DISCUSSION
NWS SAN ANGELO TX
351 PM CST SAT JAN 31 2015 .SHORT TERM... (Tonight and Sunday ) Light rain was moving north of I-20, and east of an Abilene... Brady...Mason line at 3 PM. An upper low was west of El Paso, moving slowly southeast. Rain was pushing east and ending of West Central, faster than the models indicated. Indeed at the current pace, nearly all the present rain at 3 PM will be east or north of West Central Texas by 6 PM. Kept a chance of showers going overnight, however, with the El Paso low sending weak disturbances eastward. Additional rainfall amounts will be light...ranging from a trace to a few hundredths inch. The NAM and EC models bring isolated to scattered light showers over West Central Texas tonight. The GFS model`s convective algorithm is dry. The short range HRRR model brings in scattered showers, mainly over Crockett county, the Concho Valley and areas southward. Timing was between 9 PM and 4 AM. This may actually be the best model as it seems to latched on an area of lift in the water vapor loop south of El Paso. A cold front will move through West Central Texas Sunday bringing gusty north winds by noon. This clear low level moisture and clouds. Sunshine in the afternoon should allow afternoon highs to be a 2-4 degrees warmer than today`s, despite cold air advection. .LONG TERM... (Sunday night through next Saturday) Warmer weather will make a return to West Central Texas for the first half of the week. An area of high pressure centered over the region on Monday, will slide off to our east by mid-week. A thermal ridge at 850 mb will expand east over the area, allowing high temperatures to climb from the mid 50s on Monday, to the mid 60s by Wednesday. A weak cold front approaching the area from the north Wednesday night, will wash out near Interstate 10 during the day Thursday, bringing cooler/drier air to the region. However, this will be short-lived, as a lee trough develops to our west on Friday. With a return flow developing, warmer temperatures and increasing moisture are expected. Precipitation chances may also increase for the southern half of the forecast area. An upper-level disturbance currently located over Baja California, is expected to pass by to our southeast Tuesday night/Wednesday morning. This system may bring a chance of rain to the region, mainly south of a line from San Angelo to Brownwood. This afternoon`s numerical models have once again shifted the track of the disturbance farther south and east, reducing forecast confidence. However, the models have been flip-flopping on the track for the last few model runs, and considering the system is still largely in a data-void region, this will likely continue through the next 48 hours. By then, the system will enter an improving observational/upper-air network, which may result in improved model continuity. Given the concerns mentioned above, only minimal changes were made to the rainfall forecast for the middle of the week. && .PRELIMINARY POINT TEMPS/POPS... Abilene 49 51 24 51 36 / 40 10 5 5 5 San Angelo 51 60 27 54 36 / 30 10 5 5 5 Junction 52 64 30 55 34 / 60 20 5 5 5 && .SJT WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 04/Doll
AREA FORECAST DISCUSSION
NWS HOUSTON/GALVESTON TX
1209 PM CST SAT JAN 31 2015 .AVIATION... COMPLICATED TAF PACKAGE WITH MAIN CONCERNS CENTERING AROUND MVFR TO IFR CEILINGS...TIMING RAIN ASSOCIATED WITH SEVERAL DISTURBANCES CROSSING THE AREA...AND VISIBILITY RESTRICTIONS FROM PRECIPITATION. MAIN PRECIP SHIELD ASSOCIATED WITH A 500 MB SHORTWAVE TROUGH STILL REMAINS WEST OF THE TERMINALS THIS MORNING...BUT IS SLOWLY TRANSLATING EAST TOWARDS THE INTERSTATE 35 CORRIDOR. OTHER SUBTLE WAVES IN THE MESSY SOUTHWEST FLOW ALOFT HAVE ALSO CONTRIBUTED TO SMALLER POCKETS OF -RA. GIVEN TRAJECTORY OF MAIN WAVE... THINK RAIN COLLEGE STATION/HUNTSVILLE/POTENTIALLY CONROE WILL SEE -RA AROUND 00Z AS THE MAIN 500 MB WAVE TRANSLATES NORTH OF THE REGION. VCSH TO EVEN -RA WILL BE POSSIBLE LATER THIS EVENING /03-06Z FOR THE HOUSTON TERMINALS/ AS OTHER SUBTLE WAVES CROSS THE AREA. MVFR VISIBILITY RESTRICTIONS WILL BE POSSIBLE IN HEAVIER RAIN...WITH THE BULK OF THE ACTIVITY LOOKING TO CLEAR THE AREA BETWEEN 10-12Z SUNDAY. ADDITIONALLY... CONTINUED LOW LEVEL MOISTURE RETURN WILL REPLACE PERIODS OF VFR EARLY THIS AFTERNOON WITH MVFR BY THIS EVENING WITH 10 TO 15 KNOT EASTERLY TO SOUTHEASTERLY WINDS THIS AFTERNOON TO BECOMING SOUTHEASTERLY AND LESS THAN 10 KNOTS TONIGHT AS THE REGION LOSES THE INFLUENCE OF THE SURFACE RIDGE. THE NEXT CONCERN THEN BECOMES THE TIMING OF A STRONG COLD FRONT ENTERING THE STATE ON SUNDAY AND SHOWERS /WITH POTENTIALLY AN ISOLATED THUNDERSTORM OR TWO/ DEVELOPING ALONG AND AHEAD OF THE FRONT. WINDS WILL VEER TO THE SOUTHWEST AS A PREFRONTAL TROUGH CROSSES THE TERMINALS... REACHING THE NORTHERN TERMINALS BY MID- MORNING SUNDAY. TTU-WRF RUNS HAVE BECOME INCREASINGLY ANEMIC REGARDING PRECIPITATION ALONG THE FRONT AND CONFIDENCE IS LOW WITH AREAL COVERAGE OF RAIN TOMORROW WITH MORE TIME TO REFINE. COLD FRONT LOOKS TO CLEAR THE TERMINALS AFTER THE END OF THE TAF PERIOD...BUT ANTICIPATE GUSTY WINDS IN ITS WAKE LATE SUNDAY AFTERNOON/EVENING. ADDITIONALLY...NAM12 AND RAP PROGS ARE SHOWING 975 MB WINDS OUT OF THE SOUTHWEST AROUND 30-35 KNOTS GENERALLY BETWEEN 09-12Z SUNDAY MORNING. THIS COULD POSE BORDERLINE LLWS CONCERNS DEPENDING ON IF THESE STRONGER WINDS MATERIALIZE /OR SURFACE WINDS DECREASE MORE THAN ANTICIPATED TONIGHT/. GIVEN LOW CONFIDENCE...NO MENTION WAS INCLUDED IN THE TAFS BUT WILL BE SOMETHING TO CONTINUE TO MONITOR. HUFFMAN && .PRELIMINARY POINT TEMPS/POPS... COLLEGE STATION (CLL) 62 58 65 37 49 / 40 60 60 10 0 HOUSTON (IAH) 62 58 69 41 51 / 20 50 70 20 0 GALVESTON (GLS) 62 57 64 45 50 / 20 40 50 30 0 && .HGX WATCHES/WARNINGS/ADVISORIES... TX...NONE. GM...NONE. && $$
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AREA FORECAST DISCUSSION
NWS MELBOURNE FL
402 AM EST MON FEB 2 2015 .DISCUSSION... TODAY-TONIGHT...SHORTWAVE TROUGH WILL MOVE ACROSS THE SOUTHEAST STATES AND OFFSHORE TO THE NORTH OF OUR AREA THIS EVENING. DEEP LAYER WIND FIELDS WILL INCREASE...WHICH WILL CAUSE THE ASSOCIATED COLD FRONT TO SWEEP QUICKLY ACROSS THE AREA THIS AFTERNOON. THE AIR MASS WILL INITIALLY BE DRY BUT THE MODELS SHOW PRE FRONTAL MOISTURE BAND WITH PRECIPITABLE WATER TO AROUND 1.6 INCHES. LATEST MOS POPS ARE NOT MUCH DIFFERENT FROM OUR PREVIOUS FORECAST SO HAVE KEPT LIKELY VALUES IN THE NORTH AND CHANCE VALUES IN THE SOUTH. EXPECT CONSIDERABLE CLOUD COVER TO MOVE ACROSS THE NORTH THIS MORNING WHICH WILL LIMIT HEATING AND FORECAST SOUNDINGS SHOW CAPE VALUES BELOW 500 J/KG. THE SOUTH HAS A BETTER CHANCE TO WARM UP BUT FRONTAL CONVERGENCE WILL BE WEAKENING WITH TIME. HAVE KEPT THE PREVIOUS FORECAST WHICH MENTIONS A SLIGHT CHANCE OF STORMS...BUT THE WEAK INSTABILITY AND INCREASED WIND PROFILES POINT MORE TO LOW TOPPED CONVECTION WITH SHOWERS CAPABLE OF PRODUCING STRONG/GUSTY WINDS. WILL GO WITH A LAKE WIND ADVISORY TODAY SINCE CANAVERAL PROFILERS AND FORECAST 925 MB WINDS POINT TO GUST CAPABILITY TO AROUND 30 MPH. COLD FRONT WILL PASS INTO SOUTH FLORIDA BY ABOUT 00Z SO WILL NOT CARRY ANY POPS THIS EVENING. EXPECT THE COOL/DRY AIR MASS TO PUSH MOST CLOUDINESS OUT OF THE AREA...BUT SOME STRATOCUMULUS MAY LINGER ALONG THE SOUTH COAST WHERE LOW LEVEL WINDS BECOME WEAKLY ONSHORE (NNE) LATE. MAV/MET GUIDANCE SHOWS TEMPERATURES FALLING INTO 40S FOR MOST OF THE AREA EXCEPT FOR LOWER 50S ALONG THE FAR SOUTH COAST. A FEW UPPER 30S ARE POSSIBLE IN THE FAR NORTH INTERIOR. EXTENDED...GLOBAL MODELS ARE IN UNUSUALLY FINE AGREEMENT FOR THE MAJORITY OF THE DAY 2-7 TIME FRAME. THE ONLY DIFFERENCES OF NOTE ARE SUBTLE TIMING/LOCATION DIFFERENCES W/R/T THE LOW PRES WAVE SLIDING EWD ACROSS THE GOMEX/FL IN THE LATE WED THROUGH THU AFTERNOON. TUE-THU...SRN STREAM H50 LOW OVER OLD MEX WILL OPEN UP AND SLIDE EWD ALONG THE GULF COAST AS A WEAKENING SHORT WAVE TROUGH DURING THIS PERIOD. THE FEATURE WILL DAMPEN/SHEAR OUT WED NIGHT/THU WHILE IT CROSSES THE LONG OF FL EARLY THU (CENTERED AROUND 12Z)...COMING UNDER THE INFLUENCE OF AN AMPLIFYING ERN CONUS/WRN ATLC TROUGH. NRLY SFC FLOW TUE AM VEER NE DURING THE AFTN AND EARLY EVENING AS THE LARGE SFC HIGH OVER THE SRN CONUS EXPANDS EWD. SFC LOW PRES WAVE TAKES SHAPE OVER THE WRN GOMEX TUE NIGHT AND THEN SLIDES E-ENE INTO THE ERN GOMEX BY LATE WED NIGHT AND THEN ACROSS THE NRN-CTRL PENINSULA THU MORNING...DRAGGING A FAIRLY STRONG COLD FRONT THROUGH ECFL THU AFTERNOON-EARLY EVENING. BEST RAIN CHANCES ATTM CENTERED AROUND 06Z-18Z THU (LATE WED NIGHT THRU THU MORNING). CURRENT GRIDS SHOW SCT POPS LATE TRENDING HIGHER ACROSS THE NORTH GIVEN MODEL CONSENSUS OF POSN OF NWD LIFTING WARM FRONT/SFC WAVE AND ASCD BEST MOISTURE FIELDS. LIKELY POPS ALL AREAS THU AS FRONT SLIDES RAPIDLY SWD BEHIND THE LOW PRES WAVE. MAX TEMPS SLIGHTLY BELOW CLIMO TUE...NEAR CLIMO ON WED (WELL ABOVE WED NIGHT IN INCREASING SRLY PRE-FRONTAL WIND FLOW)...TRENDING BACK TO NEAR/SLIGHTLY BELOW FOR THU AFTERNOON-THU NIGHT. FRI-SUN...VERY WEAK MID LEVEL TROUGH MOVES SE ACROSS FL FRI...WITH NW MID LEVEL FLOW DRIVING A SECONDARY NRLY SURGE AS COOL HIGH PRES PUSHES SWD INTO THE STATE. MAXES IN THE 60S AND LOWS GENERALLY IN THE 40S TO L50S...BUT LIKELY SEVERAL DEGREES WARMER ALONG THE IMMEDIATE COAST AS POST FRONTAL NRLY WINDS VEER QUICKLY NE (A RECURRING THEME THIS DRY SEASON). HIGH PRESSURE SETTLES ACROSS NRN FL SAT AND THEN EXPANDS/SHIFTS EWD INTO THE ATLC BY SUN...LEADING TO MODERATING TEMPS FOR THE LATE WEEKEND. MODELS ARE HINTING AT ANOTHER FRONTAL APPROACH OR PASSAGE AROUND NEXT MON. && .AVIATION... INCREASED LOW LEVEL WINDS HAVE NECESSITATED LOW LEVEL WIND SHEAR MENTION THROUGH ABOUT 13-14Z AT SITES EXCEPT FOR KFPR-KSUA. SOUTHWEST/WEST WINDS WILL THEN BECOME GUSTY TO AROUND 25 KNOTS AT ALL SITES. PRE FRONTAL BAND OF CONVECTION HAS RECENTLY STARTED TO TAKE SHAPE IN THE GULF OF MEXICO. THE HRRR MODEL SHOWS THE BAND REACHING NORTHERN SITES AROUND NOON AND MOVING QUICKLY THROUGH CENTRAL SECTIONS BY MID AFTERNOON AND SOUTHERN SITES LATE IN THE AFTERNOON. WILL MAKE ADJUSTMENTS IN NEXT SET OF TAFS BASED ON EXTRAPOLATION AND HRRR MODEL. && .MARINE... TODAY-TONIGHT...THE PRESSURE GRADIENT HAS BEEN GRADUALLY TIGHTENING AND WILL CONTINUE TO DO SO AS A COLD FRONT SWEEPS INTO THE NORTHERN WATERS TOWARDS MIDDAY AND THEN THROUGH THE SOUTHERN WATERS LATE IN THE AFTERNOON. HAZARDOUS CONDITIONS FOR SMALL CRAFT OPERATORS WILL EXIST...TODAY ACROSS MOST ALL OF THE WATERS AND THEN ACROSS THE OFFSHORE WATERS TONIGHT. HAVE MADE SOME MINOR ADJUSTMENTS TO THE SMALL CRAFT ADVISORY THAT WAS PREVIOUSLY IN PLACE...MAINLY TO INDICATE ONE FOR WINDS ACROSS THE NEAR SHORE WATERS...AS SEAS ARE FORECAST BELOW 7 FEET THERE. BY LATE TONIGHT THE WINDS WILL HAVE VEERED TO NORTHERLY AND DIMINISHED TO 15 KNOTS BUT SEAS WILL BE SLOW TO DIMINISH... ESPECIALLY IN THE GULF STREAM. TUE-FRI...SEAS GRADUALLY SUBSIDE THROUGH TUE THROUGH WED NIGHT AS A MODERATE NRLY BREEZE VEERS TO EAST AND THEN SE-SE. WINDS WILL VEER TO SW THU MORNING...THEN SHIFT TO NRLY THU AFTERNOON/EVENING...WITH AN EVEN STRONGER SURGE OF N TO NNE WINDS LATE THU NIGHT-FRI. WITH THE MODELS IN SUCH GOOD AGREEMENT...CONFIDENCE IS PRETTY GOOD FOR SCA CONDS TO DEVELOP...EVEN THOUGH THIS IS OUT AT DAYS 4-5. && .PRELIMINARY POINT TEMPS/POPS... DAB 75 42 63 48 / 60 0 10 10 MCO 74 44 67 50 / 60 0 10 10 MLB 77 46 68 53 / 50 10 10 10 VRB 82 48 70 54 / 50 10 10 10 LEE 72 41 65 49 / 70 0 10 10 SFB 73 41 66 48 / 60 0 10 10 ORL 72 44 66 51 / 60 0 10 10 FPR 82 48 71 53 / 50 10 10 10 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY FROM 8 AM THIS MORNING TO 6 PM EST THIS EVENING FOR COASTAL VOLUSIA-INDIAN RIVER-INLAND VOLUSIA- MARTIN-NORTHERN BREVARD-NORTHERN LAKE-OKEECHOBEE-ORANGE- OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE-ST. LUCIE. AM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM EST THIS EVENING FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ SHORT TERM...LASCODY LONG TERM....CRISTALDI
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
150 AM EST MON FEB 2 2015 .UPDATE... ISSUED AT 150 AM EST MON FEB 2 2015 THE SURFACE COLD FRONT HAS MADE IT HALF WAY THROUGH EASTERN EKNTUCKY...WITH WIDESPREAD RAINS LIKELY EXITING THE FAR EAST IN THE NEXT 1 TO 2 HOURS. HAVE ATTEMPTED TO CAPTURE THE LULL IN THE PRECIP A BIT BETTER OVER THE NEXT FEW HOURS...BEFORE THE TROUGH AXIS MOVES IN TOWARDS DAWN...USHERING IN THE MUCH COLDER AIR AND THE SNOW SHOWER ACTIVITY. UPDATES HAVE BEEN SENT. UPDATE ISSUED AT 1105 PM EST SUN FEB 1 2015 HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATION AND RADAR TRENDS. THIS LED TO HOLDING ONTO NEAR 100 POPS FOR ABOUT ANOTHER HOUR IN THE FAR WEST. OTHERWISE...THE PREVIOUS FORECAST APPEARED TO BE IN GOOD SHAPE. THE 0Z NAM AND 0Z GFS THERMAL PROFILES AND QPF GENERALLY SUPPORTS THE CURRENT FORECAST. THE HRRR CONTINUES TO BE RATHER UNIMPRESSIVE AS DOES THE RAP WHICH LEADS TO BELOW AVERAGE CONFIDENCE AT THIS TIME RANGE...AND COULD ENVISION SNOWFALL POSSIBLY ENDING UP A LITTLE LOWER. CURRENT HEADLINES WILL BE LEFT AS IS. UPDATE ISSUED AT 835 PM EST SUN FEB 1 2015 AS OF 8 PM...AN AREA OF LOW PRESSURE WAS CENTERED OVER EASTERN INDIANA WITH A STATIONARY FRONT EXTENDING EAST INTO THE MID ATLANTIC STATES WITH A COLD FRONT EXTENDING SOUTH JUST TO THE WEST OF THE INTERSTATE 65 CORRIDOR. A DRY SLOT EXTENDED FROM EASTERN OK NORTH AND NORTHEAST INTO SOUTHERN IL WITH RADAR RETURNS ACROSS KY EAST OF THIS AREA. A SFC TROUGH WHICH IS THE LEADING EDGE OF THE MUCH COLDER AIR EXTENDED WEST INTO SOUTHERN IL AND EASTERN MO.SOME SNOW IS ALSO FALLING NEAR AND BEHIND THE SFC TROUGH WHICH IS LOCATED IN ADVANCE OF THE UPPER LEVEL SHORTWAVE. TEMPERATURES HAVE RISEN FROM THE MID 30S TO UPPER 30S ON TOP OF BLACK MOUNTAIN IN THE WARM ADVECTION AHEAD OF THE COLD FRONT. THE BACK EDGE OF THE STEADIER SHOWERS IS ENTERING THE JKL CWA WITH ANOTHER AREA OF SHOWERS IN ADVANCE OF AND JUST BEHIND THE COLD FRONT. AS THE COLD FRONT WORKS EAST...WE EXPECT A RELATIVE LULL IN THE PRECIPITATION FOR A TIME IN MANY AREAS AFTER IT PASSES DURING THE OVERNIGHT UNTIL THE UPPER LEVEL TROUGH AND SFC TROUGH NEARS AND LAPSE RATES STEEPEN. ATTM...IT LOOKS LIKE THE ATMOSPHERE WILL BEGIN TO COOL TO COLD ENOUGH LEVELS FOR A MIX WITH OR CHANGEOVER TO SNOW OF ANY LINGERING SHOWERS JUST BEHIND THE COLD FRONT IN THE FAR NW GENERALLY BETWEEN 2 AND 5 AM. THE HIGHEST TERRAIN ABOVE 2500 FEET COULD ALSO CHANGEOVER DURING THAT TIME. SOMEWHAT MORE ORGANIZED SNOW SHOWERS ARE ANTICIPATED WITH THE SFC TROUGH AND IN ADVANCE OF THE SHORTWAVE AS THE COLDEST AIR WORKS IN ALOFT WHICH SHOULD ARRIVE OR DEVELOP AND ENHANCE AS IT INTERACTS WITH THE TERRAIN RISE AT THE ESCARPMENT IN OUR WESTERN OR NW CWA AROUND 6 OR 7 AM AND THEN GENERALLY TRANSLATE ACROSS THE AREA. ADDITIONAL LESS ORGANIZED SHOWERS OF RAIN OR SNOW OR A MIX MAY BE ONGOING AT THAT TIME AS WELL. RECENT NEAR TERM MODEL GUIDANCE IS NOT ALL THAT IMPRESSIVE AND THUS NOT PROVIDE MUCH CONFIDENCE IN THIS EVOLUTION LATE TONIGHT INTO MONDAY. THERE ARE HINTS OF SNOW SHOWERS AS THE RELATIVELY STRONG SHORTWAVE MOVES THROUGH AND THE LOW LEVELS HAVE AN UPSLOPE COMPONENT. THE STRENGTH OF THE SHORTWAVE...ASSOCIATED LAPSE RATES AND UPSLOPE FLOW THOUGH ARGUE FOR GENERALLY HIGH CHANCE TO LIKELY POPS FOR THE NORTH AND SOUTHEAST FOR MONDAY MORNING. AT THIS TIME...WE PLAN TO NOT ADD ANY ADDITIONAL AREAS TO THE WSW. HOWEVER...UPSTREAM TRENDS WILL BE MONITORED ALONG WITH TIMING INTO THE NW COUNTIES WHICH ON AVERAGE SHOULD BE THE COLDEST DURING THE MORNING COMMUTE FOR POSSIBLE AREAL ADDITION TO THE WSW. IN ORDER TO ACCOUNT FOR THE HIGHER TERRAIN OF FONDE MTN AREA OF WESTERN BELL COUNTY WHICH SHOULD BE FAVORED IN THE NW UPSLOPE FLOW AND BETTER MATCH START TIMES TO MY SOUTH...WE HAVE STARTED THE WSW A COUPLE OF HOURS EARLIER FOR THE VA BORDER COUNTIES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 335 PM EST SUN FEB 1 2015 19Z SFC ANALYSIS SHOWS A RATHER DEEP AREA OF LOW PRESSURE MOVING ACROSS THE MISSISSIPPI RIVER INTO ILLINOIS. A COLD FRONT FROM THIS IS STRETCHED TO THE SOUTHWEST DOWN INTO TEXAS. AS THIS LOW PUSHES FURTHER INTO THE OHIO VALLEY...THE CORE OF ITS PCPN SHIELD IS NOW ENTERING EASTERN KENTUCKY WITH LIGHT TO MODERATE RAINS OVERSPREADING THE AREA. UNDER THICK CLOUDS AND THE ARRIVING RAINS...TEMPERATURES HAVE PEAKED THIS AFTERNOON WITH READINGS IN THE MID 40S TO LOWER 50S ACROSS THE AREA. DEWPOINTS...MEANWHILE...ARE COMING UP WITH THE ARRIVING RAINS AND NOW VARY FROM THE LOW TO MID 20S IN THE EAST AND THE UPPER 30S TO LOWER 40S TO THE WEST. WIND HAVE ALSO PICKED UP WITH THE ARRIVAL OF THE RAIN WITH GUSTS TO 20 TO 25 KTS FROM THE SOUTH OVER THE CUMBERLAND VALLEY AND 15 TO 20 KTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY WHIP A SHARP TROUGH THROUGH THE SOUTHERN APPALACHIANS BY MIDDAY MONDAY. IN THE NORTHWEST FLOW THAT FOLLOWS...A TRAILING SHORTWAVE WILL PASS THROUGH EASTERN KENTUCKY INTO EARLY TUESDAY MORNING...SEEN AS STRONGEST IN THE ECMWF WHEN COMPARED TO THE NAM12 AND GFS/GEM. HAVE MAINLY FOLLOWED A MODEL BLEND THROUGH MONDAY NIGHT WITH AN EMPHASIS ON THE HIGHER RESOLUTION DETAILS FROM THE NAM12 BEFORE LEANING MORE ON THE GFS AND NAM12 WITH THE TRAILING WAVE THROUGH TUESDAY MORNING. SENSIBLE WEATHER WILL FEATURE A GOOD SOAKING RAIN FOR EAST KENTUCKY THROUGH THE EVENING AND INTO THE OVERNIGHT ALONG WITH BREEZY CONDITIONS AS THE WRAPPED UP SFC LOW MOVES THROUGH. THE LOW PASSES TO THE EAST BY SUNRISE MONDAY WITH WINDS SWITCHING TO THE WEST AND INCREASING AS THE TIGHT GRADIENT ON THE LOW/S BACKSIDE EXITS THE AREA. IN ADDITION TO THE BREEZY CONDITIONS IN THE WAKE OF THE LOW...AN ARCTIC BOUNDARY WILL BRING IN MUCH COLDER AIR FROM WEST TO EAST ACROSS THE CWA BETWEEN 08 AND 13Z RESULTING IN A SWITCH OVER FOR ANY LINGERING PCPN TO SNOW. THE WINDS WILL BECOME MORE UPSLOPE WHILE THE SFC LOW FURTHER DEEPENS INTO MONDAY MORNING. THIS WILL ADD TO THE SNOW FALL FOR OUR FAR EASTERN COUNTIES WITH THE WINDS BLOWING THE SNOW AROUND KEEPING THE VIS LOW IN ANY SHOWERS. EXPECT THE SNOW TO BE WORST BETWEEN 11 AND 15Z FOR MOST OF THE AREA WITH LIGHT ACCUMULATIONS EXPECTED ASIDE FROM THE RIDGES AND LOCATIONS IN THE FAR EAST. ALONG THOSE PLACES NEAR THE VIRGINIA BORDER SOME HIGHER SNOW TOTALS WILL BE POSSIBLE WITH BETWEEN 2 AND 3 INCHES SEEN ON THE PEAKS ABOVE 2500 FEET AND UP TO 2 INCHES ON THE LOWER RIDGES WHILE VALLEYS GENERALLY PICK UP AN INCH OR LESS. FINALLY...IN ADDITION TO THE SNOW AND WINDS...THE COLD AIR COULD MOVE IN QUICK ENOUGH...TRAILING THE RAINS AND LIMITED DRY SLOTTING TO RESULT IN ICY CONDITIONS ON AREA ROADS. FOR THIS REASON...WILL HAVE AN SPS OR WINTER WEATHER ADVISORY OUT FOR THE ENTIRE AREA...HITTING THE EAST PROGRESSIVELY HARDER FOR AMOUNTS AND IMPACTS. OUR VIRGINIA BORDER COUNTIES WILL HAVE AN ADVISORY FOR SNOW GOING UNTIL 23Z WHILE TO THE WEST THE ADVISORY WILL RUN THROUGH 19Z WITH LESSER TOTALS. THE SNOW TAPERS OFF FROM WEST TO EAST MONDAY AFTERNOON WITH CAA SENDING TEMPS DOWN INTO THE TEENS MOST PLACES BY DAWN TUESDAY...THOUGH LOW CLOUDS WILL LIKELY KEEP READINGS FROM COMPLETELY BOTTOMING OUT FOR EASTERN PARTS OF THE AREA. USED THE BCCONSSHORT FOLLOWED BY THE SUPERBLEND AS A STARTING POINT FOR TEMPERATURES...DEWPOINTS...AND WINDS THROUGH TUESDAY MORNING. MADE ONLY MINOR ADJUSTMENTS TO WINDS AND TEMPERATURES TO ACCOUNT FOR THE TERRAIN EFFECTS OF THE CAA WINDS LATE TONIGHT INTO MONDAY MORNING. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS GUIDANCE THROUGH MONDAY AFTERNOON OWING TO THE TENDENCY FOR THE MODEL/MOS GUIDANCE TO UNDER DO UPSLOPE SNOW SITUATIONS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 410 PM EST SUN FEB 1 2015 TUESDAY WILL START OUT WITH GENERALLY ZONAL FLOW ALOFT AND SURFACE HIGH PRESSURE IN PLACE. TEMPERATURES WILL WARM FROM THE PREVIOUS DAY WITH SURFACE WINDS BECOMING MORE SRLY AND SKIES CLEARING...THOUGH STILL EXPECTED TO BE A FEW DEGREES BELOW SEASONABLE NORMALS. A SHORTWAVE WILL BEGIN TO TRAVERSE ALONG A TROUGH AXIS WELL NORTH OF THE REGION...REACHING THE UPPER GREAT LAKES BY WEDNESDAY EVENING AND STRENGTHENING AS IT SHOOTS OFF TO THE SE AND ACROSS THE EASTERN PORTION OF KY. THIS COURSE OF ACTION...INCLUDING THE AMPLITUDE AND TIMING...IS VERY MUCH A RESULT OF WHICH MODEL IS CORRECT. AS OF NOW...THERE IS STILL QUITE A BIT OF DISAGREEMENT BETWEEN THE GFS AND ECMWF...WHICH LEADS TO LOW CONFIDENCE ON THE RESULTING SURFACE FEATURES. THE GFS CONTINUES TO BE THE STRONGEST WITH THE SYSTEM...SHOWING A 1009MB LOW PRESSURE SYSTEM MOVING ACROSS NEW ENGLAND WEDNESDAY EVENING. THE ECMWF IS IN A SIMILAR LOCATION FOR THE LOW...BUT IS SLIGHTLY WEAKER AT 1013MB AS OF THE 12Z RUN. A COLD FRONT WILL EXTEND SOUTHWEST OF THIS LOW...AND BRING FRONTAL PRECIPITATION TO MUCH OF THE OHIO VALLEY WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR THE GFS...AND SOMEWHAT LATER WEDNESDAY NIGHT THROUGH THURSDAY AFTERNOON FOR THE ECMWF AND GEM. REGARDLESS...THIS WILL BE A QUICK HITTING SYSTEM...WITH MUCH OF THE MOISTURE FALLING ALONG OR JUST BEHIND THE FRONTAL PASSAGE. IF THIS HOLDS TRUE...WINDS WILL MAKE A QUICK SHIFT TO THE N AND BEGIN PULLING IN MUCH COLDER AIR AROUND THE TIME THE PRECIPITATION STARTS. THIS WILL QUICKLY DROP TEMPS BELOW FREEZING...SO EXPECT ANY PRECIP THAT FALLS TO BE MAINLY IN THE FORM OF SNOW...WITH MAYBE A SMALL AMOUNT OF RAIN AT THE ONSET. HIGHS ON THURSDAY ARE ONLY EXPECTED TO REACH THE UPPER 20S TO AROUND 30. DRY AIR WILL THEN QUICKLY WORK IN AND CUT OFF ANY REMAINING SNOW POTENTIAL SOMETIME THURSDAY AFTERNOON. DO NOTE...GIVEN THE DISCREPANCIES BETWEEN THE MODELS...THE TIMING OF ONSET AND DEPARTURE IS LIKELY TO CHANGE. THIS WILL THEN LIKELY AFFECT THE SNOW TOTALS. AT THIS TIME...FORECASTING GENERALLY A HALF INCH OR LESS ACROSS THE CWA...WITH THE HIGHEST AMOUNTS IN THE SE WHERE SNOW WILL LINGER THE LONGEST AND SOME UPSLOPE FLOW WILL TAKE PLACE. AFTER THIS SYSTEM PASSES THROUGH THE REGION...UPPER LEVELS WILL SLOWLY TRANSITION BACK TO ZONAL FLOW. COLDER CANADIAN AIR FLOWING INTO THE REGION WILL EVENTUALLY GIVE WAY TO MORE SEASONABLE NORMS BY SATURDAY. HIGH PRESSURE WILL BE IN CONTROL THROUGH MUCH OF THE REMAINDER OF THE EXTENDED. OUR NEXT THREAT FOR PRECIP WILL OCCUR SOMETIME SATURDAY NIGHT/SUNDAY ON DAY 7 OF THE FORECAST AS MODELS HINT AT ANOTHER SHORTWAVE DEVELOPING OVER THE CENTRAL PLAINS. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 150 AM EST MON FEB 2 2015 MVFR/IFR CEILINGS AND OR VISIBILITIES WILL CONTINUE THROUGH THE MORNING HOURS...WITH WIDEPREAD RAINS ENDING THROUGH 08Z IN THE EAST. MUCH COLDER AIR WILL BE USHERED IN BETWEEN 10 AND 12Z...WITH SNOW SHOWER ACTIVITY PICKING UP FROM NORTHWEST TO SOUTHEAST. THE SNOW SHOWERS WILL LINGER LONGEST IN THE SOUTHEAST THROUGH EARLY THIS AFTERNOON...BEFORE TAPERING OFF. ANY MORE INTENSE SNOW SHOWERS WILL BE CAPABLE OF PRODUCING TEMPORARY LIFR VISIBILITIES. LOWER CEILINGS WILL SCATTER OUT BY DUSK. WEST TO NORTHWEST WINDS WILL CONTINUE TO OVERSPREAD THE AREA AS THE COLD FRONT EXITS EAST OVERNIGHT. SUSTAINED SPEEDS WILL BE IN THE 10 TO 15 KT RANGE...WITH GUSTS IN THE 20 TO 25 KT RANGE THROUGH EARLY THIS AFTERNOON...BEFORE DIMINISHING TOWARDS DUSK. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 AM EARLY THIS MORNING TO 6 PM EST THIS EVENING FOR KYZ087-088-118-120. WINTER WEATHER ADVISORY UNTIL 2 PM EST THIS AFTERNOON FOR KYZ086- 104-106>117-119. && $$ UPDATE...GEOGERIAN SHORT TERM...GREIF LONG TERM...JMW AVIATION...GEOGERIAN
AREA FORECAST DISCUSSION...UPDATED
NWS JACKSON KY
1111 PM EST SUN FEB 1 2015 .UPDATE... ISSUED AT 1105 PM EST SUN FEB 1 2015 HOURLY GRIDS HAVE BEEN UPDATED BASED ON RECENT OBSERVATION AND RADAR TRENDS. THIS LED TO HOLDING ONTO NEAR 100 POPS FOR ABOUT ANOTHER HOUR IN THE FAR WEST. OTHERWISE...THE PREVIOUS FORECAST APPEARED TO BE IN GOOD SHAPE. THE 0Z NAM AND 0Z GFS THERMAL PROFILES AND QPF GENERALLY SUPPORTS THE CURRENT FORECAST. THE HRRR CONTINUES TO BE RATHER UNIMPRESSIVE AS DOES THE RAP WHICH LEADS TO BELOW AVERAGE CONFIDENCE AT THIS TIME RANGE...AND COULD ENVISION SNOWFALL POSSIBLY ENDING UP A LITTLE LOWER. CURRENT HEADLINES WILL BE LEFT AS IS. UPDATE ISSUED AT 835 PM EST SUN FEB 1 2015 AS OF 8 PM...AN AREA OF LOW PRESSURE WAS CENTERED OVER EASTERN INDIANA WITH A STATIONARY FRONT EXTENDING EAST INTO THE MID ATLANTIC STATES WITH A COLD FRONT EXTENDING SOUTH JUST TO THE WEST OF THE INTERSTATE 65 CORRIDOR. A DRY SLOT EXTENDED FROM EASTERN OK NORTH AND NORTHEAST INTO SOUTHERN IL WITH RADAR RETURNS ACROSS KY EAST OF THIS AREA. A SFC TROUGH WHICH IS THE LEADING EDGE OF THE MUCH COLDER AIR EXTENDED WEST INTO SOUTHERN IL AND EASTERN MO.SOME SNOW IS ALSO FALLING NEAR AND BEHIND THE SFC TROUGH WHICH IS LOCATED IN ADVANCE OF THE UPPER LEVEL SHORTWAVE. TEMPERATURES HAVE RISEN FROM THE MID 30S TO UPPER 30S ON TOP OF BLACK MOUNTAIN IN THE WARM ADVECTION AHEAD OF THE COLD FRONT. THE BACK EDGE OF THE STEADIER SHOWERS IS ENTERING THE JKL CWA WITH ANOTHER AREA OF SHOWERS IN ADVANCE OF AND JUST BEHIND THE COLD FRONT. AS THE COLD FRONT WORKS EAST...WE EXPECT A RELATIVE LULL IN THE PRECIPITATION FOR A TIME IN MANY AREAS AFTER IT PASSES DURING THE OVERNIGHT UNTIL THE UPPER LEVEL TROUGH AND SFC TROUGH NEARS AND LAPSE RATES STEEPEN. ATTM...IT LOOKS LIKE THE ATMOSPHERE WILL BEGIN TO COOL TO COLD ENOUGH LEVELS FOR A MIX WITH OR CHANGEOVER TO SNOW OF ANY LINGERING SHOWERS JUST BEHIND THE COLD FRONT IN THE FAR NW GENERALLY BETWEEN 2 AND 5 AM. THE HIGHEST TERRAIN ABOVE 2500 FEET COULD ALSO CHANGEOVER DURING THAT TIME. SOMEWHAT MORE ORGANIZED SNOW SHOWERS ARE ANTICIPATED WITH THE SFC TROUGH AND IN ADVANCE OF THE SHORTWAVE AS THE COLDEST AIR WORKS IN ALOFT WHICH SHOULD ARRIVE OR DEVELOP AND ENHANCE AS IT INTERACTS WITH THE TERRAIN RISE AT THE ESCARPMENT IN OUR WESTERN OR NW CWA AROUND 6 OR 7 AM AND THEN GENERALLY TRANSLATE ACROSS THE AREA. ADDITIONAL LESS ORGANIZED SHOWERS OF RAIN OR SNOW OR A MIX MAY BE ONGOING AT THAT TIME AS WELL. RECENT NEAR TERM MODEL GUIDANCE IS NOT ALL THAT IMPRESSIVE AND THUS NOT PROVIDE MUCH CONFIDENCE IN THIS EVOLUTION LATE TONIGHT INTO MONDAY. THERE ARE HINTS OF SNOW SHOWERS AS THE RELATIVELY STRONG SHORTWAVE MOVES THROUGH AND THE LOW LEVELS HAVE AN UPSLOPE COMPONENT. THE STRENGTH OF THE SHORTWAVE...ASSOCIATED LAPSE RATES AND UPSLOPE FLOW THOUGH ARGUE FOR GENERALLY HIGH CHANCE TO LIKELY POPS FOR THE NORTH AND SOUTHEAST FOR MONDAY MORNING. AT THIS TIME...WE PLAN TO NOT ADD ANY ADDITIONAL AREAS TO THE WSW. HOWEVER...UPSTREAM TRENDS WILL BE MONITORED ALONG WITH TIMING INTO THE NW COUNTIES WHICH ON AVERAGE SHOULD BE THE COLDEST DURING THE MORNING COMMUTE FOR POSSIBLE AREAL ADDITION TO THE WSW. IN ORDER TO ACCOUNT FOR THE HIGHER TERRAIN OF FONDE MTN AREA OF WESTERN BELL COUNTY WHICH SHOULD BE FAVORED IN THE NW UPSLOPE FLOW AND BETTER MATCH START TIMES TO MY SOUTH...WE HAVE STARTED THE WSW A COUPLE OF HOURS EARLIER FOR THE VA BORDER COUNTIES. && .SHORT TERM...(THIS EVENING THROUGH MONDAY NIGHT) ISSUED AT 335 PM EST SUN FEB 1 2015 19Z SFC ANALYSIS SHOWS A RATHER DEEP AREA OF LOW PRESSURE MOVING ACROSS THE MISSISSIPPI RIVER INTO ILLINOIS. A COLD FRONT FROM THIS IS STRETCHED TO THE SOUTHWEST DOWN INTO TEXAS. AS THIS LOW PUSHES FURTHER INTO THE OHIO VALLEY...THE CORE OF ITS PCPN SHIELD IS NOW ENTERING EASTERN KENTUCKY WITH LIGHT TO MODERATE RAINS OVERSPREADING THE AREA. UNDER THICK CLOUDS AND THE ARRIVING RAINS...TEMPERATURES HAVE PEAKED THIS AFTERNOON WITH READINGS IN THE MID 40S TO LOWER 50S ACROSS THE AREA. DEWPOINTS...MEANWHILE...ARE COMING UP WITH THE ARRIVING RAINS AND NOW VARY FROM THE LOW TO MID 20S IN THE EAST AND THE UPPER 30S TO LOWER 40S TO THE WEST. WIND HAVE ALSO PICKED UP WITH THE ARRIVAL OF THE RAIN WITH GUSTS TO 20 TO 25 KTS FROM THE SOUTH OVER THE CUMBERLAND VALLEY AND 15 TO 20 KTS ELSEWHERE. THE MODELS ARE IN GOOD AGREEMENT ALOFT THROUGH THE SHORT TERM PORTION OF THE FORECAST AS THEY WHIP A SHARP TROUGH THROUGH THE SOUTHERN APPALACHIANS BY MIDDAY MONDAY. IN THE NORTHWEST FLOW THAT FOLLOWS...A TRAILING SHORTWAVE WILL PASS THROUGH EASTERN KENTUCKY INTO EARLY TUESDAY MORNING...SEEN AS STRONGEST IN THE ECMWF WHEN COMPARED TO THE NAM12 AND GFS/GEM. HAVE MAINLY FOLLOWED A MODEL BLEND THROUGH MONDAY NIGHT WITH AN EMPHASIS ON THE HIGHER RESOLUTION DETAILS FROM THE NAM12 BEFORE LEANING MORE ON THE GFS AND NAM12 WITH THE TRAILING WAVE THROUGH TUESDAY MORNING. SENSIBLE WEATHER WILL FEATURE A GOOD SOAKING RAIN FOR EAST KENTUCKY THROUGH THE EVENING AND INTO THE OVERNIGHT ALONG WITH BREEZY CONDITIONS AS THE WRAPPED UP SFC LOW MOVES THROUGH. THE LOW PASSES TO THE EAST BY SUNRISE MONDAY WITH WINDS SWITCHING TO THE WEST AND INCREASING AS THE TIGHT GRADIENT ON THE LOW/S BACKSIDE EXITS THE AREA. IN ADDITION TO THE BREEZY CONDITIONS IN THE WAKE OF THE LOW...AN ARCTIC BOUNDARY WILL BRING IN MUCH COLDER AIR FROM WEST TO EAST ACROSS THE CWA BETWEEN 08 AND 13Z RESULTING IN A SWITCH OVER FOR ANY LINGERING PCPN TO SNOW. THE WINDS WILL BECOME MORE UPSLOPE WHILE THE SFC LOW FURTHER DEEPENS INTO MONDAY MORNING. THIS WILL ADD TO THE SNOW FALL FOR OUR FAR EASTERN COUNTIES WITH THE WINDS BLOWING THE SNOW AROUND KEEPING THE VIS LOW IN ANY SHOWERS. EXPECT THE SNOW TO BE WORST BETWEEN 11 AND 15Z FOR MOST OF THE AREA WITH LIGHT ACCUMULATIONS EXPECTED ASIDE FROM THE RIDGES AND LOCATIONS IN THE FAR EAST. ALONG THOSE PLACES NEAR THE VIRGINIA BORDER SOME HIGHER SNOW TOTALS WILL BE POSSIBLE WITH BETWEEN 2 AND 3 INCHES SEEN ON THE PEAKS ABOVE 2500 FEET AND UP TO 2 INCHES ON THE LOWER RIDGES WHILE VALLEYS GENERALLY PICK UP AN INCH OR LESS. FINALLY...IN ADDITION TO THE SNOW AND WINDS...THE COLD AIR COULD MOVE IN QUICK ENOUGH...TRAILING THE RAINS AND LIMITED DRY SLOTTING TO RESULT IN ICY CONDITIONS ON AREA ROADS. FOR THIS REASON...WILL HAVE AN SPS OR WINTER WEATHER ADVISORY OUT FOR THE ENTIRE AREA...HITTING THE EAST PROGRESSIVELY HARDER FOR AMOUNTS AND IMPACTS. OUR VIRGINIA BORDER COUNTIES WILL HAVE AN ADVISORY FOR SNOW GOING UNTIL 23Z WHILE TO THE WEST THE ADVISORY WILL RUN THROUGH 19Z WITH LESSER TOTALS. THE SNOW TAPERS OFF FROM WEST TO EAST MONDAY AFTERNOON WITH CAA SENDING TEMPS DOWN INTO THE TEENS MOST PLACES BY DAWN TUESDAY...THOUGH LOW CLOUDS WILL LIKELY KEEP READINGS FROM COMPLETELY BOTTOMING OUT FOR EASTERN PARTS OF THE AREA. USED THE BCCONSSHORT FOLLOWED BY THE SUPERBLEND AS A STARTING POINT FOR TEMPERATURES...DEWPOINTS...AND WINDS THROUGH TUESDAY MORNING. MADE ONLY MINOR ADJUSTMENTS TO WINDS AND TEMPERATURES TO ACCOUNT FOR THE TERRAIN EFFECTS OF THE CAA WINDS LATE TONIGHT INTO MONDAY MORNING. AS FOR POPS...ENDED UP ON THE HIGH SIDE OF MOS GUIDANCE THROUGH MONDAY AFTERNOON OWING TO THE TENDENCY FOR THE MODEL/MOS GUIDANCE TO UNDER DO UPSLOPE SNOW SITUATIONS. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 410 PM EST SUN FEB 1 2015 TUESDAY WILL START OUT WITH GENERALLY ZONAL FLOW ALOFT AND SURFACE HIGH PRESSURE IN PLACE. TEMPERATURES WILL WARM FROM THE PREVIOUS DAY WITH SURFACE WINDS BECOMING MORE SRLY AND SKIES CLEARING...THOUGH STILL EXPECTED TO BE A FEW DEGREES BELOW SEASONABLE NORMALS. A SHORTWAVE WILL BEGIN TO TRAVERSE ALONG A TROUGH AXIS WELL NORTH OF THE REGION...REACHING THE UPPER GREAT LAKES BY WEDNESDAY EVENING AND STRENGTHENING AS IT SHOOTS OFF TO THE SE AND ACROSS THE EASTERN PORTION OF KY. THIS COURSE OF ACTION...INCLUDING THE AMPLITUDE AND TIMING...IS VERY MUCH A RESULT OF WHICH MODEL IS CORRECT. AS OF NOW...THERE IS STILL QUITE A BIT OF DISAGREEMENT BETWEEN THE GFS AND ECMWF...WHICH LEADS TO LOW CONFIDENCE ON THE RESULTING SURFACE FEATURES. THE GFS CONTINUES TO BE THE STRONGEST WITH THE SYSTEM...SHOWING A 1009MB LOW PRESSURE SYSTEM MOVING ACROSS NEW ENGLAND WEDNESDAY EVENING. THE ECMWF IS IN A SIMILAR LOCATION FOR THE LOW...BUT IS SLIGHTLY WEAKER AT 1013MB AS OF THE 12Z RUN. A COLD FRONT WILL EXTEND SOUTHWEST OF THIS LOW...AND BRING FRONTAL PRECIPITATION TO MUCH OF THE OHIO VALLEY WEDNESDAY EVENING THROUGH THURSDAY MORNING FOR THE GFS...AND SOMEWHAT LATER WEDNESDAY NIGHT THROUGH THURSDAY AFTERNOON FOR THE ECMWF AND GEM. REGARDLESS...THIS WILL BE A QUICK HITTING SYSTEM...WITH MUCH OF THE MOISTURE FALLING ALONG OR JUST BEHIND THE FRONTAL PASSAGE. IF THIS HOLDS TRUE...WINDS WILL MAKE A QUICK SHIFT TO THE N AND BEGIN PULLING IN MUCH COLDER AIR AROUND THE TIME THE PRECIPITATION STARTS. THIS WILL QUICKLY DROP TEMPS BELOW FREEZING...SO EXPECT ANY PRECIP THAT FALLS TO BE MAINLY IN THE FORM OF SNOW...WITH MAYBE A SMALL AMOUNT OF RAIN AT THE ONSET. HIGHS ON THURSDAY ARE ONLY EXPECTED TO REACH THE UPPER 20S TO AROUND 30. DRY AIR WILL THEN QUICKLY WORK IN AND CUT OFF ANY REMAINING SNOW POTENTIAL SOMETIME THURSDAY AFTERNOON. DO NOTE...GIVEN THE DISCREPANCIES BETWEEN THE MODELS...THE TIMING OF ONSET AND DEPARTURE IS LIKELY TO CHANGE. THIS WILL THEN LIKELY AFFECT THE SNOW TOTALS. AT THIS TIME...FORECASTING GENERALLY A HALF INCH OR LESS ACROSS THE CWA...WITH THE HIGHEST AMOUNTS IN THE SE WHERE SNOW WILL LINGER THE LONGEST AND SOME UPSLOPE FLOW WILL TAKE PLACE. AFTER THIS SYSTEM PASSES THROUGH THE REGION...UPPER LEVELS WILL SLOWLY TRANSITION BACK TO ZONAL FLOW. COLDER CANADIAN AIR FLOWING INTO THE REGION WILL EVENTUALLY GIVE WAY TO MORE SEASONABLE NORMS BY SATURDAY. HIGH PRESSURE WILL BE IN CONTROL THROUGH MUCH OF THE REMAINDER OF THE EXTENDED. OUR NEXT THREAT FOR PRECIP WILL OCCUR SOMETIME SATURDAY NIGHT/SUNDAY ON DAY 7 OF THE FORECAST AS MODELS HINT AT ANOTHER SHORTWAVE DEVELOPING OVER THE CENTRAL PLAINS. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z MONDAY EVENING) ISSUED AT 739 PM EST SUN FEB 1 2015 CIGS INITIALLY WILL BE MAINLY IN THE MVFR RANGE OR FALL INTO THE VFR RANGE EARLY IN THE PERIOD. DETERIORATION TO IFR AND BELOW CONDITIONS ARE ANTICIPATED AFTER 06Z. THE RAIN WILL THEN CHANGE TO SNOW THROUGH ABOUT 13Z AS THE COLDER AIR MOVES IN WITH REDUCED VISIBILITY AND LOWER VIS BEING THE MAIN CONCERN. SOUTH TO SOUTHWEST WINDS WILL START SHIFTING TO THE WEST SOUTHWEST AND LATER TONIGHT TO THE WEST. GUSTS AS HIGH AS 25 KT WILL BE POSSIBLE THROUGH AT LEAST 18Z ON MONDAY AS THE SYSTEM MOVES ON THROUGH. CONDITIONS SHOULD IMPROVE BACK INTO THE MVFR RANGE BETWEEN 15Z AND 21Z IN MOST LOCATIONS. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 AM TO 6 PM EST MONDAY FOR KYZ087- 088-118-120. WINTER WEATHER ADVISORY FROM 3 AM TO 2 PM EST MONDAY FOR KYZ086- 104-106>117-119. && $$ UPDATE...JP SHORT TERM...GREIF LONG TERM...JMW AVIATION...JP
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1142 PM CST SUN FEB 1 2015 .AVIATION... FOR THE 02/06Z TAFS...SCT STRATUS WILL AFFECT PORTIONS OF SE OK/SRN AR THROUGH THE OVERNIGHT/EARLY MORNING HRS BUT THESE CLOUDS SHOULD EXIT AROUND SUNRISE AS A SFC HIGH PRESSURE BUILDS OVERHEAD. CANNOT RULE OUT SOME HIGH END MVFR CIGS WITH THESE CLOUDS...BUT VFR CONDITIONS SHOULD PREVAIL OTHERWISE WITH MUCH OF THE REST OF THE AREA REMAINING NEARLY SKC FOR THE NEXT 24 HRS. NWLY WINDS PERSIST BETWEEN 10 AND 15 KTS WITH GUSTS UP TO 25 KTS. SPEEDS SHOULD DIMINISH TO 5 KTS OR LESS BY 02/18Z BEFORE BECOMING LIGHT AND VARIABLE MONDAY EVENING. /09/ && .PREV DISCUSSION... /ISSUED 959 PM CST SUN FEB 1 2015/ DISCUSSION... COLD FRONT HAS MOVED SOUTHEAST OF THE AREA WITH LARGE HIGH PRESSURE SYSTEM CENTERED OVER THE PLAINS MOVING SOUTH PROVIDING COLD AND MUCH DRIER AIR INTO THE FOUR STATE REGION. ONLY CHANGES TO THE ONGOING FORECAST WAS TO LOWER THE CLOUD COVER FOR MUCH OF THE REGION AND ADJUST THE DEW POINTS. WINDS WILL REMAIN ELEVATED TO NEAR AND ABOVE LAKE WIND CRITERIA FOR MUCH OF THE FORECAST AREA THROUGH THE EARLY MORNING MONDAY. WILL KEEP THE LAKE WIND ADVISORY IN EFFECT AS IS. /06/ PREV DISCUSSION... /ISSUED 359 PM CST SUN FEB 1 2015/ DISCUSSION... THE SCT CONVECTION HAS RAPIDLY MOVED E ACROSS LOWER E TX/NCNTRL LA THIS AFTERNOON ALONG THE COLD FRONT...WHICH EXTENDS FROM THE MS RIVER ALONG THE AR/MS BORDER SW TO LLQ...TO ELD...TO JUST N OF A IER...TO S OF A LFK LINE AS OF 21Z. THE HRRR CONTINUES TO HAVE THE BEST HANDLE ON THE ONGOING CONVECTION...WHICH SHOULD COMPLETELY EXIT THE AREA BY/SHORTLY AFTER 00Z. BEHIND THE FRONT...GUSTY NW WINDS CONTINUE TO EXPAND SE...WITH GUSTS TO 25KTS COMMON ACROSS EXTREME NE TX/SE OK/SW AR. THE SHORT TERM PROGS DO AGREE ON A 6MB PRESSURE DIFFERENCE FROM W TO E ACROSS THE CWA THIS EVENING...AND GIVEN THIS...HAVE EXPANDED THE LAKE WIND ADVISORY THROUGH 10Z MONDAY TO COVER THE REMAINDER OF THE CWA EXCEPT THE LOWER SAM RAYBURN COUNTRY OF DEEP E TX AS WELL AS THE SRN PARISHES OF NCNTRL LA...WHERE WINDS SHOULD BE A BIT MORE MARGINAL. STRONG COLD ADVECTION BEHIND THE FRONT SHOULD RESULT IN FREEZING TEMPS OVER ALL BUT THE SRN AND ERN SECTIONS OF THE REGION...DESPITE THE POST-FRONTAL STRATOCU OVER CNTRL/ERN OK NOT CLEARING UNTIL LATE TONIGHT ACROSS SE OK/SW AR/NCNTRL LA. CANADIAN SFC RIDGING WILL BEGIN TO SETTLE S ACROSS THE SRN PLAINS MONDAY...THUS WEAKENING THE GRADIENT BY DAYBREAK. HOWEVER...EVEN WITH ABUNDANT SUNSHINE...TEMPS WILL STRUGGLE TO CLIMB MUCH INTO THE 40S...STILL SOME 10-15 DEGREES BELOW NORMAL. WINDS SHOULD MOSTLY DECOUPLE BY MONDAY NIGHT AS THE SFC RIDGE MOVES OVER THE REGION...BUT SHOULD START TO SEE AN INCREASE IN CIRRUS LATE AS THE CLOSED LOW OVER SRN BAJA THIS AFTERNOON...BEGINS TO NUDGE E INTO NW OLD MX MONDAY NIGHT AND INTO S TX BY WEDNESDAY MORNING. THE INCREASED CIRRUS MAY HELP OFFSET THE MORE IDEAL RADIATIONAL COOLING THAT WOULD NORMALLY TAKE PLACE...BUT STILL EXPECTING MUCH OF THE AREA TO SEE SEVERAL HOURS OF SUBFREEZING TEMPS. THE PROGS HAVE REMAINED FAIRLY CONSISTENT WITH THE TRACK OF THIS LOW THE LAST 24 HOURS...WITH THE ELEVATED MOISTURE INCREASING BY TUESDAY AFTERNOON...WITH AREAS OF -RA DEVELOPING MAINLY OVER E TX/N LA. THE PROGS HAVE BACKED OFF CONSIDERABLY ON QPF WITH THIS SYSTEM AS IT BEGINS TO OPEN UP AND ACCELERATE E ACROSS S LA WEDNESDAY...WITH THE BEST FORCING MAINLY FOCUSED ALONG THE EXTREME SE TX/SRN LA COASTS. HAVE LOWERED POPS TO LOW CHANCE TUESDAY NIGHT AND WEDNESDAY FOR AREAS ALONG/S OF I-20...BEFORE THE NEXT SHORTWAVE CLIPPER ROUNDS THE GREAT LAKES REGION WEDNESDAY AFTERNOON. THIS NEXT SHORTWAVE SHOULD ALLOW FOR ANOTHER COLD FRONT TO NUDGE S WEDNESDAY NIGHT/THURSDAY MORNING...DRIVING TEMPS BACK DOWN TO SOME 10 DEGREES BELOW NORMAL ONCE AGAIN. CAN/T RULE OUT ISOLATED AREAS OF -RA DEVELOPING NEAR/BEHIND THE FROPA...BUT THE MOISTURE PROFILE WILL REMAIN SHALLOW WHILE THE BEST FORCING WILL BE NE OF THE AREA. SHOULD AGAIN BEGIN TO SEE A MODERATION OF TEMPS BY FRIDAY AND ESPECIALLY NEXT WEEKEND...AS TEMPS RETURN BACK ABOVE NORMAL. DRY CONDITIONS SHOULD PERSIST THROUGH NEXT WEEKEND AS WELL. PRELIMS TO FOLLOW BELOW... 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 30 46 26 53 39 / 10 0 0 0 20 MLU 34 44 25 52 35 / 10 0 0 0 20 DEQ 24 42 22 52 32 / 0 0 0 0 0 TXK 28 43 25 52 37 / 10 0 0 0 10 ELD 29 43 23 52 34 / 10 0 0 0 10 TYR 27 43 30 53 40 / 10 0 0 0 20 GGG 28 44 27 53 39 / 10 0 0 0 20 LFK 33 49 29 53 41 / 10 0 0 10 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: ARZ050-051-059>061-070>073. LA...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: LAZ001>006-010>014-021. OK...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: OKZ077. TX...LAKE WIND ADVISORY UNTIL 4 AM CST MONDAY FOR THE FOLLOWING ZONES: TXZ096-097-108>112-124>126-136>138-149>153. && $$ 09
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
346 AM EST MON FEB 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE ACROSS SOUTHERN PENNSYLVANIA THIS MORNING...DRAGGING A COLD FRONT ACROSS THE AREA. HIGH PRESSURE RETURNS ON TUESDAY. ANOTHER COLD FRONT MOVES THROUGH THE REGION WEDNESDAY NIGHT. HIGH PRESSURE BUILDS IN ONCE AGAIN LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LOPRES INVOF PIT ATTM. WHILE CWFA W/IN WARM SECTOR...RELATIVELY SPEAKING...ITS NOT ALL THAT WARM. MESONET OBS SUGGEST PLENTY OF SITEA AOB 32F ACRS NRN CWFA...N OF LINE FM OKV-IAD-NAK. HWVR...PCPN ASSOCD W/ 60-70 KT LLJ PULLING EAST...AND A GRDL WARM-UP IS TAKING PLACE. WITH THAT IN MIND...FEEL COMFY TRIMMING A FEW ZONES AT 3AM-- SOME SCHEDULED /LOUDOUN-BALT CITY/ AND SOME NOT /HAMPSHIRE-ERN MINERAL/. WHILE RADAR DEPICTION OF PCPN NOT THAT INTENSIVE W OF THE BLURDG...THERE ARE STILL SOME RETURNS SO SPOTTY FZRA STILL PSBL. THE REST OF THE ADVY IN EFFECT TIL 13Z. WL MONITOR OBS/RADAR...AND DROP ELY AS CONDS PERMIT. CDFNT IN WRN WVA WL HEAD EWD AS LOW CROSSES SRN PA. ITS LOOKING A LTL SLOWER THAN PRVS CYCLES...WHICH WL KEEP A CHC OF PCPN INTO THE MRNG. HIEST POPS IN THE EAST INVOF ISENT LIFT AHD OF FNT. THE SLOWER TIMING WL ALSO PERMIT TEMPS TO RISE FURTHER DURING THE MRNG HRS. MAXT WL OCCUR PRIOR TO NOON. CFP WL STILL TAKE PLACE DURING THE AM. THE AFTN TEMP DROP WL BE MORE DRAMATIC W/ OF THE BLURDG...AND MAY BE TEMPERED BY COMPRESSIONAL WARMING TO THE EAST. AS CAA COMES CRASHING IN ON NW FLOW...MOMENTUM IN THE MIXED LYR WL INCREASE AS HGTS RISE RAPIDLY /AND LOW DEEPENS AS WELL...INCREASING P-GRAD/. MOST MDL SNDGS SUGGEST GUSTS AOA 40 KT. HV WIND ADVY IN PLACE...WHICH APPEARS PRUDENT. OF CONCERN ARE RAP SNDGS WHICH SUGGEST 50 KT AT 2000 FT. THIS WOULD BE THE TOP OF THE MIXED LYR. DONT XPCT FULL MIXING...BUT IT COULD TRIP MTN TOPS. HV HAD GNDC THIS WINTER OFFER HIGH WINDS BEFORE THEN PULL BACK...SO WONT UPGRADE HIER ELEVS /SUCH AS THE NEW SKYLINE DR ZONES/ TO HIGH WIND WARNING JUST YET...BUT IT IS AN ISSUE THAT WL BE FWDD ON TO DAY SHIFT TO WATCH CLOSELY. THE OTHER ISSUE THAT CAA/NW FLOW BRINGS IS UPSLP SHSN. TRAJ AND DEPTH UNDER INVSN BOTH LOOK GOOD...AND GDNC CRANKING OUT A DECENT PD OF SNOW MIDDAY...W/ INCRSG RATIOS. HV PUMPED UP TTLS...ENUF TO TRIGGER ADVYS IN EFFECT TIL 00Z. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... HIPRES BLDG EWD ACRS CWFA TNGT...AND WL BE THE PRIMARY WX INFLUENCE TUE. TNGT WL MARK THE END OF CAA...W/ THE ADVCTN SIGN REVERSING DURING THE MRNG TUE. BOTH PDS WL STILL BE COLD THO...W/ MINIMAL CHGS FM GOING FCST. ALTHO SKIES WL BE MOCLR TNGT...SUSPECT CONTD WINDS WL KEEP TEMPS FM DROPPING TOO FAR. AM ON THE COOLER SIDE OF MOS...BUT DIDNT UNDERCUT IT IN THE ABSENCE OF A GOOD RADL COOLING ENVIRONMENT. MAXT TUE WL BE STRUGGLING TO EXCEED 30F ACRS NRN MD/ERN WVA. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... LOW PRESSURE TRACKS ACROSS NEW ENGLAND TUESDAY NIGHT INTO WEDNESDAY. TRAILING COLD FRONT IS EXPECTED TO REMAIN WEST OF THE AREA...RESULTING IN A DRY FORECAST FOR THE CWA EXCEPT POSSIBLY A RAIN/SNOW MIX WEDNESDAY AFTERNOON OVER THE POTOMAC HIGHLANDS. TUESDAY NIGHT LOW TEMPS WILL BE IN THE 20S...FOLLOWED BY NEAR NORMAL HIGHS IN THE 40S ACROSS MOST OF THE FORECAST AREA WEDNESDAY. CHARLOTTESVILLE-FREDERICKSBURG CORRIDOR MIGHT REACH 50. MODELS ARE NOT YET IN GOOD AGREEMENT ABOUT TIMING OF THE COLD FROPA ACROSS THE CWA...WITH THE 00Z GFS BRINGING IT THROUGH WEDNESDAY NIGHT AND THE 00Z ECMWF HOLDING OFF UNTIL THURSDAY. MODELS ARE CONSISTENT THAT AVAILABLE MOISTURE WILL BE LIMITED. PTYPE WILL BE HIGHLY DEPENDENT ON TIMING OF THIS SYSTEM...SO CONFIDENCE IS LOW AT THIS POINT. LOW TEMPS WEDNESDAY NIGHT EXPECTED TO BE IN THE 20S AGAIN. COLD ADVECTION BEHIND THE FRONT THURSDAY KEEPS HIGH TEMPS BELOW FREEZING OVER MOST OF THE CWA...EXCEPT OVER SRN MD AND THE VA PIEDMONT WHERE HIGHS IN THE MID 30S ARE LIKELY. HIGH PRESSURE BUILDS IN AT THE END OF THE WORK WEEK WITH TEMPS AROUND 10-15 DEGREES BELOW NORMAL. LOW PRESSURE MAY IMPACT THE AREA AT SOME POINT OVER THE WEEKEND. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... LLJ SLIDING E OF TERMINALS THIS MRNG. AS LLWS RMK IN TAFS E OF BLURDG FOR BGNG OF MRNG PUSH...BUT NOT NEARLY AS SUBSTANTIVE AS THE OVNGT HRS. FLGT CONDS HV BEEN MORE OPTIMISTIC THAN PRVSLY PROGGED. HV RESTRICTIONS ACRS THE BOARD...BUT MAINLY MVFR OUTSIDE OF BWI. STILL OPPORTUNITY FOR CIGS TO DROP BTWN EXIT ROUND OF PCPN AND BEFORE CFP. IN TERMS OF PTYPE...TEMPS AT ALL TERMINALS HV WARMED SUFFICIENTLY. MUCH OF THE PCPN HAS ACTUALLY MVD EAST...BUT MORE WL ARRIVE COINCIDENT W/ FNT. AT THIS POINT...XPCT ONLY RAIN. XPCT CFP 12Z MRB...14 OR 15Z ELSW. POST-FROPA...CLDS WL SCATTER OUT AND WNDS WL VEER NWLY/PICK UP SGFNTLY. SUSTAINED WNDS BHD FNT ARND 20 KT...W/ A FEW GUSTS REACHING 40-45 KT...SPCLY DURING THE AFTN. THIS WL IMPACT THE AFTN PUSH. SUNSET WL MARK THE BGNG OF THE END AS THE GRADIENT SUBSIDES. WNDS WONT BE NEALY AS MUCH OF AN ISSUE AFTER MIDNGT. HIPRES TUE WL MEAN VFR AND LGT WNDS...BACKING SWLY. VFR CONDITIONS EXPECTED TUESDAY NIGHT AND WEDNESDAY. S-SW WINDS WEDNESDAY...WITH SOME GUSTS TO AROUND 15KT POSSIBLE. PERIODS OF SUB-VFR POSSIBLE WEDNESDAY NIGHT AND/OR THURSDAY AS A COLD FRONT MOVES THROUGH. VFR EXPECTED LATE WEEK. NW WINDS GUSTING TO 20-25 KT POSSIBLE THURSDAY. && .MARINE... GNLY LGT WNDS ACRS THE WATERS THIS MRNG AS MIXING POOR. THERE IS A STRONG LLJ...MUCH OF WHICH ISNT MIXING DOWN. THE SERN SXN OF THE MARINE AREA PROVING TO BE THE EXCEPTION ATTM. AS A CDFNT NEARS...PCPN WL END...AND THE OPPORTUNITY FOR MIXING WL IMPRV A BIT. HV SCA IN PLACE TO ACCT FOR THIS. THE BIGGER CONCERN WL BE POST FROPA...WHEN WINDS WL VEER NWLY AND PICK UP SGFNTLY. A LTL WIGGLE ROOM IN EXACT TIMING...BUT THE PEAK PD WL INCL THE MID AND LT AFTN HRS...LASTING INTO ELY EVNG. GLW IN PLACE FOR THIS PD...WHEN MDL SNDGS SUGGEST GUSTS 40-45 KT. WL LKLY NEED SCA/S BYD THAT... BUT DONT WANT TO CONFUSE ISSUE W/ RAMPING UP AND RAMPING DOWN HAZARDS. TUE SHUD BE MUCH QUIETER TUE AS HIPRES BLDS. SCA CONDS MAY LINGER FOR A PORTION OF THAT TIME. SMALL CRAFT ADVISORY POSSIBLE WEDNESDAY UNDER S-SW FLOW AS PRESSURE GRADIENT INCREASES AHEAD OF AN APPROACHING COLD FRONT. SMALL CRAFT ADVISORY LIKELY BY THURSDAY AFTER THE COLD FRONT MOVES THROUGH...WITH POTENTIAL FOR GALES. WINDS DIMINISH FRIDAY AS HIGH PRESSURE BUILDS IN. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR DCZ001. MD...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MDZ501. WIND ADVISORY FROM 8 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR MDZ003-004-501-502. WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR MDZ003>006-502-503-505-507-508. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR MDZ005-006-011-013-014-016>018-503>508. VA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR VAZ503. WIND ADVISORY FROM 8 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR VAZ025>031-501-503>505-507-508. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR VAZ036>040-050>057-502-506. WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ501- 503-505. WIND ADVISORY FROM 8 AM THIS MORNING TO MIDNIGHT EST TONIGHT FOR WVZ050>053-055-501>506. WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR WVZ051>053. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ530>543. GALE WARNING FROM NOON TODAY TO 1 AM EST TUESDAY FOR ANZ530>543. && $$ SYNOPSIS...HTS/KCS NEAR TERM...HTS SHORT TERM...HTS LONG TERM...KCS AVIATION...HTS/KCS MARINE...HTS/KCS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
358 AM EST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EST SUN FEB 1 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. TO THE SOUTH...A VIGOROUS SHRTWV TROUGH INTO NRN IL WAS BRINGING HEAVY SNOW FROM IA INTO THE SRN LAKES. AT THE SFC...DRY NE FLOW PREVAILED THROUGH LAKE SUPERIOR AND UPPER MI BETWEEN A 1036 MB HIGH OVER ERN NORTH DAKOTA AND A 1003 MB LOW OVER ERN IL. 900 MB TEMPS AROUND -22C PROVIDED ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...INVERSION HEIGHTS AROUND 3K FT AND A DGZ BELOW 1K FT HAS LIMITED INTENSITY AND ACCUMULATION POTENTIAL. TONIGHT...EXPECT THE WINDS TO GRADUALLY BACK TO NRLY AS THE IL LOW MOVES TO THE E AND THE HIGH BUILDS INTO THE CNTRL PLAINS. WITH A RELATIVELY LIGHT WIND FIELD...LAND BREEZE EFFECTS AND THE DEVELOPMENT OF LOCALIZED CIRCULATIONS OR AREAS OF CONVERGENCE WILL BE MORE LIKELY. THE HIGHER RES MODELS SUGGEST THAT A BAND MAY DEVELOP THAT WOULD AFFECT FAR ERN OR WRN ALGER COUNTY TONIGHT. INVERSION HEIGHTS REMAINING AROUND 3K FT SHOULD LIMIT ACCUMULATION POTENTIAL TO A FEW INCHES. THERE MAY ALSO BE A SHORELINE PARALLEL BAND NEAR THE WEST BUT CONFIDENCE IN WHERE IT MAY AFFECT THE SHORELINE IS LOW. BESIDES THE LES...TEMPS WILL FALL BELOW ZERO TONIGHT...ESPECIALLY OVER THE FAR ERN COUNTIES AND ALONG THE WI BORDER OF THE INTERIOR WEST. FORTUNATELY...WITH THE LIGHT WINDS AND SOME LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS SHOULD REMAIN IN THE -10 TO -20 RANGE...NOT REACHING ADVY CRITERIA. MON...SOME LINGERING LES IN THE N TO NW SNOWBELTS AS 900 MB TEMPS WILL BE AROUND -22C WILL BE PUSHED OFFSHORE AS A TROUGH DEVELOPS OVER NRN MN INTO NRN LAKE SUPERIOR AND THE HIGH PRES SHIFTS TO THE OH VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 358 AM EST MON FEB 2 2015 GENERALLY LIGHT WNW WIND LES TUE INTO EARLY TUE NIGHT WITH 850MB TEMPS AROUND -20C. EXPECT 1-3 INCHES OF SNOW IN THE WNW WIND SNOWBELTS FROM 12Z TUE TO 06Z WED. ATTENTION IN THE LONG TERM IS LARGELY WITH LES AND ASSOCIATED HAZARDS LATE TUE NIGHT THROUGH WED NIGHT ALONG AND BEHIND A SHORTWAVE/COLD FRONT. THE SHORTWAVE ENERGY IS SHOWN BY MAJORITY OF MODELS TO STAY S OF THE CWA...ALTHOUGH THE NAM DOES BRING ENERGY AND RESULTING LIGHT QPF AMOUNTS OVER MOST OF UPPER MI TUE NIGHT. THE SFC TROUGH/COLD FRONT LOOKS TO MOVE THROUGH THE CWA LATE TUE NIGHT INTO WED MORNING. THE TRAILING 850MB THERMAL TROUGH AXIS WILL PASS THROUGH THE AREA WED AFTERNOON AND EVENING...BRINGING 850MB TEMPS AS LOW AS -28C IN THE NW FLOW. MODEL SOUNDINGS SUGGEST THAT LAKE INDUCED EQUILIBRIUM LEVELS WILL RISE ABOVE 11KFT UNDER THE THERMAL TROUGH AXIS...POINTING TO MODERATE TO HEAVY LES IN THE NW WIND SNOWBELTS. DENDRITE SIZE SHOULD BE PRETTY SMALL DUE TO THE EXTENT OF THE COLD AIRMASS PUTTING MOST OF THE CONVECTIVE LAYER COLDER THAN -20C. WHILE THE SMALL FLAKES WILL LIMIT ACCUMULATIONS SOMEWHAT...THE THREAT OF LOW VIS AND BLOWING/DRIFTING SNOW WILL BE MORE SUBSTANTIAL. DO EXPECT LOCALLY VERY POOR CONDITIONS ALONG LAKE SUPERIOR AS THE FRONT PASSES LATE TUE NIGHT OR EARLY WED MORNING AS WELL. THE LES WILL WEAKEN WED NIGHT AS A SFC RIDGE MOVES INTO WRN LAKE SUPERIOR. WILL KEEP QPF AMOUNTS SIMILAR TO PREVIOUS FORECAST WITH 0.30-0.35 INCHES IN THE NW WINDS SNOWBELTS...WHICH LEADS TO SNOWFALL AMOUNTS GREATER THAN 6 INCHES IN THOSE LOCATIONS. WILL CONTINUE TO MENTION EVENT IN HWO THOUGH A HEADLINE WILL PROBABLY BE NEEDED AT SOME POINT. WARMER TEMPS AND SW FLOW BEHIND THE SFC RIDGE AND AHEAD OF A SFC TROUGH WILL KEEP SNOW OUT OF THE LAND FORECASTS FOR MUCH OF THU AND THU NIGHT. THERE IS STILL QUITE OF A BIT OF UNCERTAINTY FOR FRI INTO THE WEEKEND AS DETAILS WITH A COUPLE OF CLIPPER SYSTEMS REMAIN UNCERTAIN ON FRI INTO FRI NIGHT AND SAT INTO SUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1201 AM EST MON FEB 2 2015 MVFR CONDITIONS WITH LIGHT SNOW SHOWERS WILL CONTINUE AT SAW AND CMX OVERNIGHT IN A N FLOW. IWD WILL SEE MVFR CONDITIONS TONIGHT IN THE SNOW SHOWERS. IWD AND SAW WILL BACK WINDS TO THE SOUTHWEST AND PUSH THE LAKE EFFECT CLOUDS NORTH OF THE AREA AND SHOULD GO VFR MON MORNING WHILE CMX STAYS IN THE LAKE EFFECT MVFR CATEGORY CLOUDS THROUGH THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 350 PM EST SUN FEB 1 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH ON MONDAY...THEN TURN TO THE NORTHWEST BEHIND THE TROUGH ON TUESDAY. WINDS THROUGH TUESDAY AT OR BLO 30 KTS. HEAVY FREEZING SPRAY OVER PORTIONS OF LK SUPERIOR ON MONDAY NIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES IN GUSTS WEDNESDAY AND WEDNESDAY EVENING. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING FROM 6 PM THIS EVENING TO 6 AM EST TUESDAY FOR LSZ266-267. HEAVY FREEZING SPRAY WARNING FROM 4 PM THIS AFTERNOON TO 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...TITUS AVIATION...07 MARINE...JLA
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1201 AM EST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 411 PM EST SUN FEB 1 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. TO THE SOUTH...A VIGOROUS SHRTWV TROUGH INTO NRN IL WAS BRINGING HEAVY SNOW FROM IA INTO THE SRN LAKES. AT THE SFC...DRY NE FLOW PREVAILED THROUGH LAKE SUPERIOR AND UPPER MI BETWEEN A 1036 MB HIGH OVER ERN NORTH DAKOTA AND A 1003 MB LOW OVER ERN IL. 900 MB TEMPS AROUND -22C PROVIDED ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...INVERSION HEIGHTS AROUND 3K FT AND A DGZ BELOW 1K FT HAS LIMITED INTENSITY AND ACCUMULATION POTENTIAL. TONIGHT...EXPECT THE WINDS TO GRADUALLY BACK TO NRLY AS THE IL LOW MOVES TO THE E AND THE HIGH BUILDS INTO THE CNTRL PLAINS. WITH A RELATIVELY LIGHT WIND FIELD...LAND BREEZE EFFECTS AND THE DEVELOPMENT OF LOCALIZED CIRCULATIONS OR AREAS OF CONVERGENCE WILL BE MORE LIKELY. THE HIGHER RES MODELS SUGGEST THAT A BAND MAY DEVELOP THAT WOULD AFFECT FAR ERN OR WRN ALGER COUNTY TONIGHT. INVERSION HEIGHTS REMAINING AROUND 3K FT SHOULD LIMIT ACCUMULATION POTENTIAL TO A FEW INCHES. THERE MAY ALSO BE A SHORELINE PARALLEL BAND NEAR THE WEST BUT CONFIDENCE IN WHERE IT MAY AFFECT THE SHORELINE IS LOW. BESIDES THE LES...TEMPS WILL FALL BELOW ZERO TONIGHT...ESPECIALLY OVER THE FAR ERN COUNTIES AND ALONG THE WI BORDER OF THE INTERIOR WEST. FORTUNATELY...WITH THE LIGHT WINDS AND SOME LAKE MODERATION/LAKE EFFECT CLOUDS...WIND CHILLS SHOULD REMAIN IN THE -10 TO -20 RANGE...NOT REACHING ADVY CRITERIA. MON...SOME LINGERING LES IN THE N TO NW SNOWBELTS AS 900 MB TEMPS WILL BE AROUND -22C WILL BE PUSHED OFFSHORE AS A TROUGH DEVELOPS OVER NRN MN INTO NRN LAKE SUPERIOR AND THE HIGH PRES SHIFTS TO THE OH VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 350 PM EST SUN FEB 1 2015 COLD CONDITIONS WITH BELOW NORMAL TEMPS EXPECTED THIS WEEK AS RIDGING FROM EASTERN RUSSIA AND THE BERING SEA TO THE WESTERN CONUS ALLOWS TROUGHING TO EXPAND ACROSS THE GREAT LAKES FM EASTERN CANADA. RIDGING BEGINS TO FLATTEN BY END OF THE EXTENDED PERIOD SUGGESTING THAT TEMPS WILL BOUNCE BACK TOWARD NORMAL OR MAYBE ABOVE BEYOND NEXT WEEKEND. DAYTIME HIGHS FOR A COUPLE DAYS WILL STAY IN THE SINGLE DIGITS BUT OTHERWISE WILL BE IN THE TEENS. NIGHTTIME LOWS WILL MAINLY BE IN THE SINGLE DIGITS BLO ZERO TO THE SINGLE DIGITS ABOVE. MAY HAVE TO DEAL WITH WIND CHILL ISSUES...ESPECIALLY ON THURSDAY MORNING. COLDEST DAYS LIKELY WEDNESDAY AND THURSDAY AS CORE OF ARCTIC AIR WITH H85 TEMPS BLO -25C SWEEPS OVER THE UPPER GREAT LAKES. WIDESPREAD SNOW CHANCES STILL ON THE LOWER SIDE IN THIS PATTERN. FOR LAST COUPLE DAYS...PRIMARY EXTENDED MODELS OF ECMWF/GFS AND GEM-NH ALONG WITH GFS ENSEMBLES HAVE HINTED AT BETTER SHOT OF SNOW OVER MUCH OF THE UPPER LAKES REGION FRIDAY AFTERNOON INTO SATURDAY AS A COLD FRONT SLIDES ACROSS THE AREA. DETAILS STILL NEED TO BE SORTED OUT THOUGH AS MODEL CONSISTENCY IS LACKING. AT THE BEGINNING OF THE LONG TERM...HIGH PRESSURE CENTER SETTLES TO THE LOWER MISSISSIPP RIVER VALLEY ON MONDAY EVENING. A TROUGH WILL BE APPROACHING LK SUPERIOR FM NORTHERN ONTARIO. WEAK SHORTWAVE/PV ANAMOLY SLIDES THROUGH AND SOUNDINGS EVEN INLAND SHOW MARGINAL DEEP MOISTENING H8-H5 WITH WEAK LIFT. LGT SNOW OR FLURRIES MOST AREAS LATER MONDAY EVENING INTO THE OVERNIGHT. BIGGER IMPACT MAY OCCUR OVER NORTHERN KEWEENAW PENINSULA AS BAND OF MODERATE TO POSSIBLY HEAVY LES COULD BE ONGOING. LIFT FM THE DISTURBANCE ALONG WITH H85 TEMPS NEAR -20C YIELDS 1000-850MB LAPSE RATES OVER 9C/KM WHERE STRONGER CONVERGENCE COMES TOGETHER. LOCAL HIRES WRF MODEL SEEMS REASONABLE SHOWING OVER 0.05 INCH OF QPF PER HOUR IN HEAVIER BANDING. SO WITH SLR/S OVER 20:1...COULD BE OVER 1 INCH OF SNOW PER HOUR...WHICH FITS THIS TYPE OF LES REGIME. DOES APPEAR THAT WITH ARRIVAL OF TROUGH THE HEAVIEST SNOW WILL NOT LAST PROBABLY MORE THAN A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL. OVERALL...SEEMS LIKE MODELS/PATTERN RECOGNITION POINTS TO ADVY FOR TIP OF KEWEENAW MONDAY EVENING...BEFORE THE LES SINKS ACROSS REST OF KEWEENAW AND BECOMES MORE MULTIBAND IN TYPE. CONTINUE TO MENTION IN HWO. ONCE THE SFC TROUGH MOVES THROUGH LATE MONDAY NIGHT INTO TUESDAY MORNING AND LARGER SCALE FORCING EVADES...EXPECT NW FLOW LES THROUGH TUESDAY NIGHT. LOW INVERSIONS BLO 4KFT AND NEUTRAL TO ANTICYLONIC FLOW WILL LIMIT INTENSITY OF LES DESPITE ALL OF THE CLOUD BEING WITHIN THE DGZ. FLUFFY ACCUMS EXPECTED BUT LOW IMPACT AS WINDS WILL BE LIGHT. AS THIS OCCURS...LOW PRESSURE SYSTEM MOVES OVER THE NORTHERN PLAINS AND EVENTUALLY SPREADS LGT SNOW OVER THE WESTERN GREAT LAKES REGION ON TUESDAY NIGHT. NAM FARTHER NORTH WITH THE QPF COMPARED TO THE MORE CONSISTENT ECWMF/GFS AND GEM-NH. WILL SHOOT FOR A MAINLY DRY FORECAST AWAY FM THE LK SUPERIOR LES. PRIMARY HAZARDOUS WEATHER POTENTIAL WILL BE TIED TO LAKE EFFECT AND BLSN/DRSN THAT RAMPS UP WEDNESDAY AND WEDNESDAY NIGHT FOR AREAS NEAR LK SUPERIOR FAVORED BY NORTHWEST WINDS. THIS IS IN WAKE OF THE LOW PRESSURE SYSTEM AND ASSOCIATED COLD FRONT THAT CROSS THE AREA ON TUESDAY NIGHT. INVERSION HEIGHTS RISING TO AT LEAST 8KFT AND LAKE EQL OVER 10KFT POINT TO MODERATE TO HEAVY SNOW. DUE TO DEPTH OF COLD THOUGH...SOUNDINGS INDICATE MOST OF THE LAKE EFFECT CONVECTIVE LAYER WILL BE AT TEMPS BLO -20C. SO...LOOKING AT SMALL SNOW FLAKES GOOD AT REDUCING VSBY...BUT NOT PILING UP A LOT OF SNOW. WINDS IN THE MIXED LAYER 25-30 KTS...SO BLSN/DRSN WILL BE PREVALENT WITH THE FINE SNOW FLAKES. EXPECT THERE WILL NEED TO BE SOME WINTER WEATHER HEADLINES CENTERED ON WEDNESDAY INTO WEDNESDAY NIGHT. AWAY FM THE LES AND BLSN/DRSN...APPEARS CONDITIONS OVER AT LEAST INTERIOR WEST WILL BE CLOSE TO WIND CHILL ADVISORY CRITERIA LATE WEDNESDAY NIGHT INTO THURSDAY MORNING. EXPECT READINGS 20 TO 25 BLO ZERO WHICH IS CLOSE TO...BUT NOT QUITE REACHING CRITERIA OF 25 TO 35 BLO. WILL CONTINUE TO MENTION THIS IN THE HWO...BUT IS NOT APPEARING TO BE AN OVERWHELMING LOW WIND CHILL EVENT. ANOTHER TROUGH...REALLY MORE OF A WARM FRONT ALOFT...SLIDES OVER NORTHERN ONTARIO AND LK SUPERIOR THURSDAY AFTN THROUGH THURSDAY NIGHT. WINDS BACKING SW AHEAD OF THE TROUGH IN LOW-LEVELS WILL PUSH LES OVER LK SUPERIOR AND WINDS APPEAR TO HAVE TOO MUCH WESTERLY COMPONENT TO RESULT IN LES OFF LK MICHIGAN FM KISQ TO KERY. MID- LEVEL MOISTURE WITH WEAK LIFT MAY SQUEEZE OUT LGT SNOW OR FLURRIES FOR MOST OF THE CWA. CONSISTENCY NOT THERE YET FOR FRIDAY AND SATURDAY SO WILL RUN WITH FORECAST CONSENSUS ATTM. BEST CHANCES OF A WIDESPREAD SNOW PROBABLY FRIDAY NIGHT WITH INCREASING UNCERTAINTY FOR THAT ON SATURDAY. FRONT WILL BE IN THE VCNTY AND LATEST INDICATIONS FM MODELS AND HAND DRAWN PROG FM WPC SHOWS IT MAINLY SOUTH OF AREA ON SUNDAY WITH LOW CHANCES FOR LES IN AN EASTERLY FLOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1201 AM EST MON FEB 2 2015 MVFR CONDITIONS WITH LIGHT SNOW SHOWERS WILL CONTINUE AT SAW AND CMX OVERNIGHT IN A N FLOW. IWD WILL SEE MVFR CONDITIONS TONIGHT IN THE SNOW SHOWERS. IWD AND SAW WILL BACK WINDS TO THE SOUTHWEST AND PUSH THE LAKE EFFECT CLOUDS NORTH OF THE AREA AND SHOULD GO VFR MON MORNING WHILE CMX STAYS IN THE LAKE EFFECT MVFR CATEGORY CLOUDS THROUGH THE PERIOD. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 350 PM EST SUN FEB 1 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH ON MONDAY...THEN TURN TO THE NORTHWEST BEHIND THE TROUGH ON TUESDAY. WINDS THROUGH TUESDAY AT OR BLO 30 KTS. HEAVY FREEZING SPRAY OVER PORTIONS OF LK SUPERIOR ON MONDAY NIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES IN GUSTS WEDNESDAY AND WEDNESDAY EVENING. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... NONE. LAKE SUPERIOR... NONE. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...JLA AVIATION...07 MARINE...JLA
AREA FORECAST DISCUSSION...UPDATE
NWS JACKSON MS
1140 PM CST SUN FEB 1 2015 .UPDATE...AREA RADARS SHOWS THE LAST OF THE RAINS OVER SOUTHEAST MISS. LATEST HRRR KEEPS THE SHOWERS AROUND UNTIL 09Z. SO HAVE EXTENDED AND LOWERED POPS IN THE SOUTHEAST FOR THE NEXT SEVERAL HOURS. ALSO HAVE REMOVED THE MENTION OF FLURRIES ACROSS THE NORTHEAST FOR THE REST OF THE NIGHT INTO EARLY MONDAY. OTHERWISE THE REST OF FORECAST APPEARS TO BE ON TRACK./17/ && .PREV DISCUSSION... /ISSUED 333 PM CST SUN FEB 1 2015/ DISCUSSION...TONIGHT THROUGH SUNDAY...THE MAIN WEATHER IMPACT THROUGH THE SHORT TERM IS THE COLD FRONT THAT IS CURRENTLY SITUATED FROM NORTHWEST MISSISSIPPI INTO EAST CENTRAL TEXAS. SHOWERS AND THUNDERSTORMS HAVE DEVELOPED ALONG THE LINE AND AND THIS ACTIVITY WILL MOVE ACROSS THE ARKLAMISS INTO THE EVENING HOURS. DECENT FORCING COMBINED WITH MU CAPES OF AROUND 200-500 J/KG AND 0-6KM SHEAR OF 60KTS WILL ALLOW FOR STRONG TO SEVERE STORMS THIS AFTERNOON AND EVENING. THE WINDS BECOME MORE UNIDIRECTIONAL AS THE BOUNDARY APPROACHES SO EXPECT THE TORNADO POTENTIAL TO BE VERY LIMITED...WITH THE MAIN CONCERN BEING DAMAGING WIND GUSTS AND POSSIBLY HAIL TO THE SIZE OF QUARTERS WITH STORMS ALONG THE BOUNDARY. A LIMITED RISK FOR STRONG TO SEVERE STORMS IS CURRENTLY IN THE HWO FOR MUCH OF THE AREA THIS AFTERNOON THROUGH MID EVENING. THE BOUNDARY WILL MOVE TO THE EAST OF THE AREA BY LATE EVENING WITH SOME LIGHT POST FRONTAL SHOWERS AND POSSIBLY A FEW FLURRIES IN THE NORTHEAST DURING THE OVERNIGHT HOURS AS COLD AIR ADVECTION INCREASES AND TEMPS DROP. COOL HIGH PRESSURE WILL BUILD OVER THE AREA ON MONDAY WITH HIGHS ONLY CLIMBING INTO 40S FOR MOST OF THE AREA. A COLD NIGHT IS ON TAP MONDAY NIGHT AS HIGH PRESSURE REMAINS OVER THE AREA AND RADIATIONAL COOLING PREVAILS WITH LOWS FALLING INTO THE MID 20S. LITTLE WILL CHANGE ON TUESDAY WITH HIGH PRESSURE RIDGING CONTINUING TO PREVAIL...BUT THE SURFACE FLOW WILL BEGIN TO TURN AROUND TO THE SOUTH AND TEMPERATURES WILL BE A LITTLE WARMER WITH HIGHS IN THE 50S. BY WEDNESDAY A SHORT WAVE WILL MOVE ACROSS EAST TEXAS INTO LOUISIANA AND CURRENTLY THE GLOBAL MODELS SUGGEST THAT MOISTURE WILL INCREASE OUT AHEAD OF IT WITH SHOWERS POSSIBLE MAINLY SOUTH OF I-20 DURING THE AFTERNOON SPREADING NORTHWARD WEDNESDAY NIGHT. THE ECMWF/GEM ARE FURTHER NORTH THAN THE GFS WITH THE SHORT WAVE AND MOISTURE...SO WILL LEAN TOWARDS THE ECMWF. EXPECT MOST OF THE PRECIPITATION TO MAINLY BE LIGHT WITH THE HEAVIEST ACCUMULATIONS OVER THE SOUTHERN PORTIONS OF THE AREA. THE SHORT WAVE WILL MOVE EAST OF THE AREA WEDNESDAY NIGHT. ON THURSDAY A COLD FRONT WILL DIVE SOUTH ACROSS THE AREA BRINGING WITH IT LIGHT SHOWERS AND MUCH COLDER AIR. THE ECMWF SUGGEST POSSIBLY A MIXED BAG OF SNOW AND RAIN POSSIBLE THURSDAY AFTERNOON/EVENING AS THE UPPER TROUGH MOVES ACROSS THE AREA...BUT WITH THE TIMING OF IT DURING THE AFTERNOON HOURS WILL HOLD OFF ON THAT FOR NOW AND KEEP THE PRECIP LIQUID. HIGH PRESSURE WILL BUILD IN AND PREVAIL FOR THE REMAINDER OF THE PERIOD WITH WARMING TEMPERATURES BY SUNDAY./15/ && .AVIATION...EXPECT SCATTERED TO BROKEN CLOUD DECKS IN THE 2 TO 4 KFT (OCCASIONALLY MVFR) RANGE AT MOST TAF SITES UNTIL A FEW HOURS AFTER DAYBREAK TOMORROW. AFTER THAT POINT VFR CONDITIONS SHOULD PREVAIL LATER TOMORROW INTO TOMORROW NIGHT. GUSTY NORTHWEST WINDS TONIGHT INTO EARLY TOMORROW SHOULD LIGHTEN UP SOME HEADING INTO TOMORROW AFTERNOON AND THEN TREND MORE LIGHT AND VARIABLE HEADED INTO TOMORROW NIGHT. CURRENT SHOWERS AND STORMS IN MAINLY SOUTHEASTERN MS WILL BE GONE BY MIDNIGHT. /BB/ && .PRELIMINARY POINT TEMPS/POPS... JACKSON 34 42 26 53 / 25 6 0 2 MERIDIAN 35 46 25 54 / 68 9 0 3 VICKSBURG 32 43 24 54 / 8 5 0 2 HATTIESBURG 37 50 26 56 / 83 7 0 3 NATCHEZ 32 42 26 53 / 27 5 0 3 GREENVILLE 31 40 26 51 / 9 7 0 2 GREENWOOD 31 40 24 51 / 10 10 0 2 && .JAN WATCHES/WARNINGS/ADVISORIES... MS...NONE. LA...NONE. AR...NONE. && $$ BB/15
AREA FORECAST DISCUSSION
NWS NORTH PLATTE NE
1156 PM CST SUN FEB 1 2015 .SYNOPSIS... ISSUED AT 316 PM CST SUN FEB 1 2015 H5 ANALYSIS THIS MORNING HAS A SHORTWAVE TROUGH OF LOW PRESSURE OVER THE MID MISSOURI VALLEY NEAR OMAHA. THIS FEATURE EXTENDS SOUTH INTO THE OZARKS AND ARKLATEX. A CUTOFF LOW WAS LOCATED OVER NORTHERN MEXICO WITH A RIDGE EXTENDING UP THE WEST COAST OF THE CONUS. FURTHER EAST...A TROUGH OF LOW PRESSURE EXTENDED FROM HUDSON BAY INTO THE CANADIAN MARITIMES. AT THE SURFACE...STRONG LOW PRESSURE WAS LOCATED OVER SRN ILLINOIS. HIGH PRESSURE WAS LOCATED OVER EASTERN NORTH DAKOTA. IN BETWEEN THESE TWO FEATURES...A NICE PRESSURE GRADIENT AND GUSTY WINDS WERE PRESENT ACROSS NEBRASKA. THIS HAS LED TO SOME BLOWING SNOW ISSUES TDY...MAINLY EAST OF HIGHWAY 83 FROM NORTH PLATTE TO VALENTINE. FURTHER WEST...WINDS HAVE BEGUN TO RELAX SOME...ESPECIALLY IN THE PANHANDLE. LIGHT SNOW CONTINUED OVER THE FAR EASTERN ZONES THIS AFTERNOON...AND A WINTER WEATHER ADVISORY REMAINS IN EFFECT ROUGHLY EAST OF A LINE FROM VALENTINE TO ARNOLD FOR SNOW AND BLOWING SNOW. UNDER CLEAR TO MOSTLY CLOUDY SKIES...READINGS AS OF 3 PM CST...RANGED FROM 4 ABOVE AT AINSWORTH AND ONEILL...TO 14 AT IMPERIAL. && .UPDATE... ISSUED AT 759 PM CST SUN FEB 1 2015 A LITTLE WORK 0N THE FORECAST TO LOWER TEMPERATURES TOWARD MESONET REPORTS PRODUCES AN AREA OF -20 TO -30 WIND CHILL READINGS TONIGHT. A WIND CHILL ADVISORY IS NOW IN EFFECT FOR PARTS OF WESTERN AND NORTH CENTRAL NEBRASKA. UPDATE ISSUED AT 559 PM CST SUN FEB 1 2015 WIND SPEEDS HAVE PEAKED AND ARE ON THE WAY DOWN TOWARD LIGHT AND VARIABLE BY 02Z. THE WINTER WEATHER ADVISORY WILL BE ALLOWED TO EXPIRE AT 6 PM CST. THE REST OF THE FORECAST IS ON TRACK. WE WILL BE WATCHING HOW QUICKLY TEMPERATURES TUMBLE AFTER SUNSET. THE FORECAST TONIGHT IS CLOSE TO THE RAP MODEL && .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 WINTER STORM CONTINUES TO EXIT TO THE EAST. SHOULD SEE WINDS BEGIN TO DIMINISH IN THE NEXT FEW HOURS...AFTER SUNSET...AS WE DECOUPLE. RADAR RETURNS ARE DIMINISHING...AND SNOW/BLOWING SNOW WILL BECOME LESS OF A CONCERN. HOWEVER STILL HAVING A FEW REPORTS OF VISIBILITIES AROUND 1SM SO WILL CONTINUE THE ADVISORY UNCHANGED THROUGH 00Z. ON TOP OF THE SNOW/BLOWING SNOW IS THE CAA TAKING PLACE. TEMPS GENERALLY IN THE SINGLE DIGITS ACROSS ALL BUT THE SW ZONES. STRONGEST WINDS ARE OVER N CENTRAL...WHICH IS WERE TEMPS ARE AROUND 5 DEGREES. THE COMBINATION OF WINDS AND COLD TEMPS ARE PUSHING WIND CHILL VALUES NEAR -15 TO -20 DEGREES. THIS IS APPROACHING WIND CHILL ADVISORY LEVELS. WILL CONTINUE THE WSW FOR SNOW/BLSN AND INCLUDE THE MENTION OF WIND CHILLS EARLY THIS EVENING. THE CONCERN IS AS THE SNOW ENDS EXPECT SKIES TO CLEAR. 1035MB HIGH SETTLES OVERHEAD EARLY THIS EVENING. THIS WILL COMBINE WITH THE FRESH SNOW OF SEVERAL INCHES ACROSS MUCH OF THE AREA TO PRODUCE AN EXCELLENT RADIATIONAL COOLING ENVIRONMENT. TEMPS SHOULD QUICKLY TANK AS WINDS DIMINISH. WIND CHILLS COULD FALL/CONTINUE IN ADVISORY CATEGORY AFTER THE WINTER WX ADVISORY EXPIRES...BUT WILL KEEP IT SIMPLE AND ONLY HAVE ONE HEADLINE GOING FOR NOW AND LET THE EVENING SHIFT MODIFY. AS FOR LOWS...DROPPED BELOW COLDEST MET GUIDANCE AS TYPICAL FOR CLEAR SKIES AND LIGHT WINDS AS SYSTEM DEPARTS. MODELS SHIFT THE HIGH SE AFTER MIDNIGHT AND WAA BEGINS WITH SOUTHERLY WINDS ON THE INCREASE. THE BATTLE BETWEEN THE SNOW PACK AIDING IN A DECOUPLED BL VERSES RISING TEMPS WITH THE WAA. HAVE FOLLOWED THE GUIDANCE TREND AND BOTTOMED TEMPS AROUND MIDNIGHT WITH RISING TEMPS TOWARDS MORNING. THIS RAISED ANOTHER CONCERN ABOUT THE LENGTH NEEDED FOR A WIND CHILL ADVISORY. TOMORROW WAA ADVECTION CONTINUES WITH 850 MB TEMPS RISING TO OR ABOVE 0C FOR NEARLY ALL BY 18Z. SW NEB PUSHES TOWARDS 5C BY THE AFTERNOON. THE SNOW PACK WILL LIMIT MIXING...ALTHOUGH WINDS BECOME WESTERLY...DOWNSLOPING. DECIDED TO REMAIN CONSERVATIVE OVER ALL BUT THE SOUTHWEST AND HIGHER TERRAIN IN THE EASTERN PANHANDLE...AND KEPT TEMPS AT OR BELOW GUIDANCE. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 316 PM CST SUN FEB 1 2015 MONDAY NIGHT THROUGH WEDNESDAY...AN ACTIVE MID RANGE PATTERN WILL CONTINUE INTO THE MIDWEEK ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. THE PATTERN WILL BE HIGHLIGHTED BY A WARM FRONTAL PASSAGE MONDAY NIGHT INTO EARLY TUESDAY...FOLLOWED BY AN ARCTIC COLD FRONT AND MID LEVEL FRONT WEDNESDAY...WHICH WILL BRING SOME ACCUMULATING SNOWS TO THE FORECAST AREA. BEGINNING MONDAY NIGHT...ARCTIC HIGH PRESSURE WILL MOVE FROM THE EASTERN DAKOTAS INTO MINNESOTA. THIS WILL ALLOW A WARM FRONT TO LIFT ACROSS THE WEST AND CENTRAL CWA MONDAY NIGHT AND ACROSS THE EASTERN ZONES EARLY TUESDAY MORNING. AT THE SAME TIME...A WEAK IMPULSE WILL TRACK SOUTHEAST ACROSS SOUTH DAKOTA INTO NERN NEBRASKA. THOUGH THE MAIN ENERGY WITH THIS IMPULSE WILL BE ACROSS SOUTH DAKOTA INVOF THE ARCTIC FRONT...ON THE SRN PERIPHERY OF THE IMPULSE...WE COULD SEE SOME WEAK LIFT ALONG THE WARM FRONT EARLY TUESDAY. BUFKIT FCST SOUNDINGS ACROSS THE NORTHEASTERN CWA TUESDAY MORNING HAVE A THERMAL PROFILE...INDICATIVE OF LIGHT FREEZING PCPN/ALTERNATING WITH LIGHT SNOW. BASED ON THESE FACTORS...DECIDED TO INSERT A MENTION OF LIGHT SNOW OR LIGHT FZ RAIN IN THE NORTHEAST TUESDAY MORNING INVOF THE FRONT. AS FOR LOWS MONDAY NIGHT...GIVEN THE SNOW COVER PRESENT ACROSS THE FORECAST AREA...TRENDED LOWS TOWARD THE COOLER MET GUIDANCE. FOR TUESDAY...HIGHS WILL VARY WIDELY WITH READINGS IN THE LOWER 30S INVOF THE WARM FRONT ACROSS THE FAR NORTHEAST...TO THE LOWER 50S IN THE FAR SOUTHWEST. FOR LATE TUESDAY NIGHT INTO WEDNESDAY...THE MID RANGE MODEL SOLUTIONS CONTINUE TO INDICATE A GOOD CHANCE FOR MEASURABLE SNOW ACROSS WESTERN AND NORTH CENTRAL NEBRASKA. AN ARCTIC COLD FRONT WILL DROP SOUTH ACROSS THE FORECAST AREA WEDNESDAY WHILE AN AREA OF STRONG MID LEVEL FRONTOGENESIS WILL TRAIL THE FRONT ACROSS THE CENTRAL CONUS. THE FORECAST CHALLENGE WITH THIS SYSTEM WILL BE THE FRONTAL TIMING AND THE POSSIBILITY OF SOME FREEZING PCPN IN ASSOCIATION WITH THE SURFACE FRONT. THE MID RANGE MODEL SOLUTIONS THIS MORNING WERE ABOUT 6 HRS APART WITH THEIR FRONTAL TIMING. THE GFS IS MORE AGGRESSIVE WITH THE FRONT WHILE THE NAM IS 6 HRS SLOWER. FOR THE FRONTAL TIMING...DECIDED TO COMPROMISE BETWEEN THE GFS AND NAM SOLNS FOR THE FRONTAL TIMING AND RESULTANT ONSET OF PRECIPITATION. WITH THIS IN MIND...TRIMMED BACK PRECIPITATION CHANCES TUESDAY EVENING TO THE FAR NORTHWEST. FOR OVERNIGHT TUESDAY AND WEDNESDAY...LITTLE CHANGE WAS MADE TO THE INHERITED GRIDS WITH 40 TO 50 POPS RETAINED WEDNESDAY. WITH RESPECT TO HIGHS WEDNESDAY...WITH BOTH MODELS CLEARING THE FRONT THROUGH THE FORECAST AREA BY LATE MORNING...HIGHS WILL BE EARLY WITH FALLING TEMPS THEREAFTER. FINALLY WITH RESPECT TO PTYPES...DECIDED TO INSERT A MENTION OF FREEZING RAIN ALONG THE LEADING EDGE OF THE ARCTIC FRONT AS CROSS SECTIONS ARE INDICATING A SMALL WINDOW OF WARMER AIR IMMEDIATELY BEHIND THE SURFACE ARCTIC FRONT. LONG RANGE...WEDNESDAY NIGHT THROUGH SUNDAY...ARCTIC HIGH PRESSURE WILL BUILD IN BEHIND THE ARCTIC FRONT WEDNESDAY EVENING...BEFORE SHIFTING INTO THE OZARKS OVERNIGHT. LOWS WILL BE VERY COLD WEDNESDAY NIGHT WITH READINGS RANGING FROM -4 IN THE EAST...TO AROUND 10 IN THE WEST. READINGS COLD BE COLDER...ESPECIALLY IF THE HIGH IS SLOWER TO MOVE OUT WEDS EVENING. BY THURSDAY...RIDGING ALOFT WILL PUSH INTO THE WESTERN CONUS...ALLOWING WARMER PACIFIC AIR TO PUSH INTO THE CENTRAL AND SRN PLAINS BEGINNING THURSDAY...AND CONTINUING THROUGH SUNDAY. HIGHS WILL REBOUND BACK INTO THE 30S THURSDAY...FOLLOWED BY 40S AND 50S FRIDAY...AND 50S SATURDAY AND SUNDAY. MAINLY DRY CONDS ARE EXPECTED IN THE LONG RANGE PERIODS...HOWEVER...THERE WILL BE A MINIMAL THREAT FOR RAIN OR SNOW SATURDAY NIGHT IN THE NORTH. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1153 PM CST SUN FEB 1 2015 HIGH PRESSURE AT THE SURFACE WAS CENTERED OVER WESTERN NEBRASKA AT 02.05Z WHICH WILL MIGRATE EASTWARD THROUGH TONIGHT. WINDS ACROSS THE AREA WILL BE LIGHT AND VARIABLE AS THE HIGH PASSES BUT WILL TURN TO THE SOUTH AND INCREASE SLIGHTLY FOR MOST LOCATIONS BY 02.12Z. AS THE BOUNDARY LAYER MIXES FOR THE AFTERNOON...LOOKING AT WINDS INCREASING WHICH WITH THEN FALL BACK BELOW 12KTS AROUND SUNSET. IN GENERAL...VFR CEILINGS ARE EXPECTED...HOWEVER THERE IS A SUGGESTION FROM ONE MODEL FOR THE POTENTIAL FOR SOME LOWER /MVFR/ STRATUS MOVING INTO NORTH CENTRAL NEBRASKA ALONG A SHALLOW COLD FRONT MONDAY EVENING. CONFIDENCE ISN/T HIGH ENOUGH YET TO LOWER THE FLIGHT CATEGORY SO JUST LOWERED CEILINGS TO 4K FEET UP AT KVTN AS THIS MOISTURE MOVES INTO THE REGION. && .LBF WATCHES/WARNINGS/ADVISORIES... WIND CHILL ADVISORY UNTIL 10 AM CST /9 AM MST/ MONDAY FOR NEZ004>010-023>029-038-094. && $$ UPDATE...CDC SYNOPSIS...CLB SHORT TERM...MASEK LONG TERM...CLB AVIATION...BROOKS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
238 AM EST MON FEB 2 2015 .SYNOPSIS... A MAJOR WINTER STORM WILL IMPACT THE REGION TODAY. UP TO A FOOT OF SNOW IS EXPECTED IN CENTRAL NEW YORK WITH 5 TO 8 INCHES IN NORTHEAST PENNSYLVANIA. ONCE THIS STORM MOVES OFF THE COAST TONIGHT...BITTERLY COLD AIR WILL SETTLE INTO THE REGION AGAIN...LASTING THROUGH MOST OF THE WEEK. && .NEAR TERM /THROUGH TODAY/... RADAR SHOWS SNOW SHIELD CONTINUING TO MOVE NORTHEAST ACRS C NY AND NE PA AS WAA OR ISENTROPIC LIFT CONTINUES TO INCREASE OVER THE REGION. THE UPPER LEVEL JET STRUCTURE WAS LEADING TO A RIGHT ENTRANCE REGION JET CIRCULATION OVER NY AND PA WITH A LEFT EXIT REGION MOVING NORTH TWD THE REGION FROM THE SOUTHERN STREAM. THE AGEO CIRC THAT RESPONDS TO THIS JET CONFIGURATION PRESSES THE LOW-LEVEL ISENTROPES FARTHER SOUTH AS THE LEFT EXIT LEADS TO SIGNIFICANT FLOW UP THE ISENTROPES. ADDITIONALLY THE UPPER LEVEL SHORT WAVE THAT WAS LEADING TO THESE UPPER JET STRUCTURES WAS MOVING EASTWARD AND WILL REACH OH AND THE ERN LAKES BY 12Z AND CNTRL NY BY 18Z AND WRN NEW ENGLAND BY 00Z. THIS UPR LVL WAVE WILL ALSO BE LIFTING THE ISENTROPES AS THE WAVE MOVES E...LEADING TO IMPRESSIVE LIFTING WITH THIS SYSTEM OVER C NY AND NE PA. MODEL RADARS INDICATE THAT THE HEAVIEST SNOW WILL OCCUR BETWEEN ROUGHLY 6Z-9Z AND 12-15Z FROM SW TO NE. BELIEVE UP TO 2 INCHES PER HOUR IS MOST LIKELY ACRS NC NY WHERE SNOW TO LIQUID RATIOS WILL BE HIGHER. BELIEVE HEAVIEST SNOW WILL BE ACRS NC NY WHERE 10-14 INCHES WILL LIKELY OCCUR. FARTHER S...ACRS MUCH OF THE FINGER LAKES AND SC NY/NRN TIER OF ERN PA...LOOKS LIKE 8-12 INCHES. FARTHER S...EXPECT 5 TO 8 INCHES AT BEST. WARMER AIR WILL MAKE IT TO THE NRN TIER OF ERN PA AS PER 18Z RUNS OF THE NAM...GFS...RGEM AND THE 2.5 KM HI RES CANADIAN MODELS AND THE LATEST HRRR AND RAP MODELS BY 12Z TO 15Z MON. I USED ALL THIS NEW GUIDC TO ADJUST THE ZR AND IP FARTHER N INTO THE NRN TIER OF ERN PA MON AM. MORE SLEET AND FREEZING RAIN IN THE AVP AREA TO POCONOS WILL CUT SNOW AMNTS DOWN. FOR NOW HAVE 5 TO 8 INCHES WITH ARND .1 TO .2 INCHES OF ICE. FOR MONDAY AFTERNOON...NORTHWEST WINDS PICK UP AND GUST TO 25 MPH...ESP IN C NY AND FAR NRN PA...SO ADDED BLOWING AND DRIFTING SNOW MONDAY AFTERNOON TO WINTER STORM WARNING IN THESE AREAS. WILL ALSO ADD TO AN UPDATED DSS BRIEFING. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ARCTIC ARE WILL SPILL BACK DOWN FROM CANADA ON THE BACK SIDE OF THE CYCLONE. APPARENT TEMPERATURES FOR THE NORTH AND EAST RANGE FROM -10F TO -18F OVERNIGHT, BORDERLINE FOR A WIND CHILL ADVISORY. WE WON`T CONSIDER AN ADVISORY AT THIS POINT, AS WE DON`T WISH TO DISTRACT FROM THE CURRENT STORM SCENARIO. AFTER A DRY, COLD DAY TUESDAY...INCLUDING SOME WEAK LAKE ACTIVITY TO THE NORTHWEST...ANOTHER WAVE WILL DIP DOWN ACROSS NY LATE TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL HAVE LIMITED MOISTURE BUT SHOULD STILL PRODUCE 2 TO 3 INCHES OF NEW SNOW. THE REAL IMPACT OF THE WAVE WILL BE TO USHER IN ANOTHER ARCTIC BLAST FOR THURSDAY. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 2 AM UPDATE... LITTLE CHANGE. POPULATED WITH CURRENT WPC GUIDANCE. WEAK SYSTEM CENTERED SOUTH OF REGION WILL BRING LIGHT SNOW. LITTLE TO ADD TO PREVIOUS DISCUSSION. PREVIOUS DISCUSSION FROM SUNDAY AFTERNOON... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... 1230 AM UPDATE... WIDESPREAD IFR VSBYS ACROSS THE TERMINALS. VSBYS UNDER 1SM BY 8Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS NOW, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MIDDAY. THE SNOW TAPERS OFF BUT GUSTY WINDS COULD CAUSE BLOWING SNOW KEEPING VSBYS IFR AT TIMES. ALSO DURING THE AFTN THE LOW LEVEL FLOW GOES TO NW STARTING THE LAKE EFFECT AND ALSO WRAP AROUND. NY TERMINALS 2 TO 3 MILES. CIGS MOSTLY 1 TO 2K FT WILL DROP SOME THROUGH 14Z THEN SLOWLY IMPROVE. EXCEPTION MAY BE ITH AND BGM IN THE AFTN WITH THE LES. EAST WINDS 5 T0 10 KTS THIS MORNING. WINDS SHIFTING TO THE NORTHWEST 16 TO 19Z AT 10 KTS INCREASING TO 10 TO 15 WITH GUSTS TO 20-25 KTS. SLOWLY DIMINISHING AFTER 00Z. OUTLOOK... TONIGHT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR PAZ038>040-043-044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 015>018-022>025-036-037-044>046-055>057-062. && $$ SYNOPSIS...MLJ NEAR TERM...DJN SHORT TERM...DJP LONG TERM...DJP/TAC AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1252 AM EST MON FEB 2 2015 .SYNOPSIS... A MAJOR WINTER STORM WILL IMPACT THE REGION TODAY. UP TO A FOOT OF SNOW IS EXPECTED IN CENTRAL NEW YORK WITH 5 TO 8 INCHES IN NORTHEAST PENNSYLVANIA. ONCE THIS STORM MOVES OFF THE COAST TONIGHT...BITTERLY COLD AIR WILL SETTLE INTO THE REGION AGAIN...LASTING THROUGH MOST OF THE WEEK. && .NEAR TERM /THROUGH TODAY/... RADAR SHOWS SNOW SHIELD CONTINUING TO MOVE NORTHEAST ACRS C NY AND NE PA AS WAA OR ISENTROPIC LIFT CONTINUES TO INCREASE OVER THE REGION. THE UPPER LEVEL JET STRUCTURE WAS LEADING TO A RIGHT ENTRANCE REGION JET CIRCULATION OVER NY AND PA WITH A LEFT EXIT REGION MOVING NORTH TWD THE REGION FROM THE SOUTHERN STREAM. THE AGEO CIRC THAT RESPONDS TO THIS JET CONFIGURATION PRESSES THE LOW-LEVEL ISENTROPES FARTHER SOUTH AS THE LEFT EXIT LEADS TO SIGNIFICANT FLOW UP THE ISENTROPES. ADDITIONALLY THE UPPER LEVEL SHORT WAVE THAT WAS LEADING TO THESE UPPER JET STRUCTURES WAS MOVING EASTWARD AND WILL REACH OH AND THE ERN LAKES BY 12Z AND CNTRL NY BY 18Z AND WRN NEW ENGLAND BY 00Z. THIS UPR LVL WAVE WILL ALSO BE LIFTING THE ISENTROPES AS THE WAVE MOVES E...LEADING TO IMPRESSIVE LIFTING WITH THIS SYSTEM OVER C NY AND NE PA. MODEL RADARS INDICATE THAT THE HEAVIEST SNOW WILL OCCUR BETWEEN ROUGHLY 6Z-9Z AND 12-15Z FROM SW TO NE. BELIEVE UP TO 2 INCHES PER HOUR IS MOST LIKELY ACRS NC NY WHERE SNOW TO LIQUID RATIOS WILL BE HIGHER. BELIEVE HEAVIEST SNOW WILL BE ACRS NC NY WHERE 10-14 INCHES WILL LIKELY OCCUR. FARTHER S...ACRS MUCH OF THE FINGER LAKES AND SC NY/NRN TIER OF ERN PA...LOOKS LIKE 8-12 INCHES. FARTHER S...EXPECT 5 TO 8 INCHES AT BEST. WARMER AIR WILL MAKE IT TO THE NRN TIER OF ERN PA AS PER 18Z RUNS OF THE NAM...GFS...RGEM AND THE 2.5 KM HI RES CANADIAN MODELS AND THE LATEST HRRR AND RAP MODELS BY 12Z TO 15Z MON. I USED ALL THIS NEW GUIDC TO ADJUST THE ZR AND IP FARTHER N INTO THE NRN TIER OF ERN PA MON AM. MORE SLEET AND FREEZING RAIN IN THE AVP AREA TO POCONOS WILL CUT SNOW AMNTS DOWN. FOR NOW HAVE 5 TO 8 INCHES WITH ARND .1 TO .2 INCHES OF ICE. FOR MONDAY AFTERNOON...NORTHWEST WINDS PICK UP AND GUST TO 25 MPH...ESP IN C NY AND FAR NRN PA...SO ADDED BLOWING AND DRIFTING SNOW MONDAY AFTERNOON TO WINTER STORM WARNING IN THESE AREAS. WILL ALSO ADD TO AN UPDATED DSS BRIEFING. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY/... ARCTIC ARE WILL SPILL BACK DOWN FROM CANADA ON THE BACK SIDE OF THE CYCLONE. APPARENT TEMPERATURES FOR THE NORTH AND EAST RANGE FROM -10F TO -18F OVERNIGHT, BORDERLINE FOR A WIND CHILL ADVISORY. WE WON`T CONSIDER AN ADVISORY AT THIS POINT, AS WE DON`T WISH TO DISTRACT FROM THE CURRENT STORM SCENARIO. AFTER A DRY, COLD DAY TUESDAY...INCLUDING SOME WEAK LAKE ACTIVITY TO THE NORTHWEST...ANOTHER WAVE WILL DIP DOWN ACROSS NY LATE TUESDAY INTO WEDNESDAY. THIS SYSTEM WILL HAVE LIMITED MOISTURE BUT SHOULD STILL PRODUCE 2 TO 3 INCHES OF NEW SNOW. THE REAL IMPACT OF THE WAVE WILL BE TO USHER IN ANOTHER ARCTIC BLAST FOR THURSDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /06Z MONDAY THROUGH FRIDAY/... 1230 AM UPDATE... WIDESPREAD IFR VSBYS ACROSS THE TERMINALS. VSBYS UNDER 1SM BY 8Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS NOW, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MIDDAY. THE SNOW TAPERS OFF BUT GUSTY WINDS COULD CAUSE BLOWING SNOW KEEPING VSBYS IFR AT TIMES. ALSO DURING THE AFTN THE LOW LEVEL FLOW GOES TO NW STARTING THE LAKE EFFECT AND ALSO WRAP AROUND. NY TERMINALS 2 TO 3 MILES. CIGS MOSTLY 1 TO 2K FT WILL DROP SOME THROUGH 14Z THEN SLOWLY IMPROVE. EXCEPTION MAY BE ITH AND BGM IN THE AFTN WITH THE LES. EAST WINDS 5 T0 10 KTS THIS MORNING. WINDS SHIFTING TO THE NORTHWEST 16 TO 19Z AT 10 KTS INCREASING TO 10 TO 15 WITH GUSTS TO 20-25 KTS. SLOWLY DIMINISHING AFTER 00Z. OUTLOOK... TONIGHT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR PAZ038>040-043-044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 015>018-022>025-036-037-044>046-055>057-062. && $$ SYNOPSIS...MLJ NEAR TERM...DJN SHORT TERM...DJP LONG TERM...DJP AVIATION...TAC
AREA FORECAST DISCUSSION
NWS BISMARCK ND
340 AM CST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FOCUS FOR THE SHORT TERM IS LIGHT SNOW. A WEAK UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW CURRENTLY OVER MONTANA WILL CONTINUE TO PROPAGATE SOUTHEAST THIS MORNING...EVENTUALLY SKIRTING SOUTHWEST NORTH DAKOTA. REGIONAL RADAR IS SHOWING SOME LIGHT BANDS OF SNOW ACROSS CENTRAL AND EASTERN MONTANA ASSOCIATED WITH THIS LOW. THIS AREA OF SNOW IS EXPECTED TO SLOWLY SAG SOUTH AND EAST THROUGH THE MORNING HOURS. THE MAIN QUESTION IS WHETHER OR NOT THIS AREA OF SNOW WILL HOLD TOGETHER AND HOW FAR EAST IT WILL MOVE. LATEST SHORT TERM GUIDANCE SUGGESTS THAT THE AREA OF SNOW WILL BRUSH WESTERN AND SOUTHERN NORTH DAKOTA THIS MORNING BUT WILL DIMINISH IN INTENSITY LEAVING ONLY A DUSTING TO LESS THAN A HALF INCH OF SNOW ACROSS PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA. FEEL THE 09 UTC HRRR HAS A PRETTY GOOD HANDLE ON THE SITUATION AS IT IS PRETTY CLOSE IN DEPICTING CURRENT SNOW BANDS IN EASTERN MONTANA. THE 09 UTC HRRR CONTINUES TO BRING THAT BAND OF SNOW EASTWARD INTO WESTERN NORTH DAKOTA THIS MORNING...BUT DIMINISHES AND SCATTERS OUT THE SNOW LATER THIS MORNING. FROM THERE OUR ATTENTION TURNS TO TONIGHT WHEN WE HAVE YET ANOTHER CHANCE FOR SNOW. ALL THE MAJOR MODELS ARE SHOWING A WELL DEFINED AREA OF SNOW ENTERING THE REGION AROUND MIDNIGHT AND SPREADING SOUTH AND EAST THROUGH THE DAY TUESDAY. THE MODELS ARE ALSO CONSISTENT WITH RESPECT TO LOCATION AND AMOUNTS OF PRECIPITATION. AT THIS TIME IT APPEARS WEST CENTRAL NORTH DAKOTA IS THE MOST FAVORED LOCATION FOR SNOWFALL...WITH AROUND 2 INCHES TOTAL ACCUMULATION POSSIBLE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FORECAST CONCERNS IN THE LONG TERM ARE SNOW CHANCES TUESDAY AND TUESDAY NIGHT...AND THEN PRECIPITATION CHANCES AND TYPE FRIDAY THROUGH SATURDAY. DETERMINISTIC MODELS ARE IN REASONABLE AGREEMENT WITH THE SYSTEM MOVING THROUGH LATE MONDAY NIGHT AND TUESDAY. THE GFS IS THE OUTLIER WITH THE QPF PLACEMENT WITH THIS SYSTEM. ALL OTHER MODELS ARE FARTHER NORTH AND EAST. UTILIZED A MODEL BLEND WITH THE NAM/SREF/GEM/ECMWF AND GFS. THUS NOT TOTALLY DISCOUNTING THE GFS TRACK BUT THIS DOES RESULT IN A LITTLE FARTHER NORTHERN TRACK WITH THE QPF. PREVIOUS TRACK HAD HIGHEST SNOW TOTALS FROM AROUND BEACH TO SOUTH OF BISMARCK AND IS NOW BETWEEN BEACH AND WILLISTON...THROUGH BISMARCK...TO ELLENDALE. AND WITH LESSER AMOUNTS IN THE FAR SOUTHWEST. OVERALL NOT A BIG CHANGE AND GENERALLY 1-2 INCHES OVER ALL BUT THE FAR SOUTHWEST WHERE ACCUMULATIONS MAY TOTAL AN INCH OR LESS...AND THE FAR NORTH CENTRAL FROM SHERWOOD AND MOHALL TO RUGBY AND NORTH WHERE AMOUNTS ARE EXPECTED TO BE A HALF INCH OR LESS. OF COURSE THE RESULTING TRACK IS STILL SUBJECT TO CHANGE...BUT THE TOTAL SNOW AMOUNTS HAVE BEEN VERY CONSISTENT FOR THE PAST TWO DAYS. AFTER A DRY PERIOD WEDNESDAY THROUGH THURSDAY NIGHT WE SEE ANOTHER SERIES OF IMPULSES MOVING THROUGH A STRONG NORTHWEST FLOW FRIDAY THROUGH SATURDAY NIGHT AND INTERACTING WITH THE BAROCLINIC ZONE. BY THIS TIME THE BAROCLINIC ZONE HAS SHIFTED FARTHER NORTH OVER NORTHERN INTO EASTERN NORTH DAKOTA. THERE ARE ALREADY TIMING DIFFERENCES WITH THE GFS MUCH QUICKER WITH THE FIRST IMPULSE AND ITS ASSOCIATED SURFACE LOW MOVING THROUGH MUCH QUICKER ON FRIDAY THAN BOTH THE ECMWF/GEM. THERE ARE ALSO DIFFERENCES IN THE EVOLUTION OF THE BAROCLINIC ZONE AS THE ECMWF KEEPS IT FROM NORTHERN INTO EASTERN NORTH DAKOTA FRIDAY AND FRIDAY NIGHT...THEN SAGS IT SOUTH THROUGH ALL BUT THE FAR SOUTHWEST BY SATURDAY NIGHT. THE QUICKER GFS DROPS THE BZ SOUTH FRIDAY...LIFTS IT BACK NORTH ON SATURDAY AND DROPS IT BACK DOWN SATURDAY NIGHT BEHIND A QUICK MOVING CLIPPER. THE GEM BRINGS IT DOWN SLIGHTLY ON FRIDAY THEN BEGINS TO LIFT IT WELL NORTH OF THE STATE ON SATURDAY. WITH ALL THAT...SEE NO REASON AT THIS TIME TO DEVIATE FROM A MODEL BLEND FOR POPS WHICH BRINGS MAINLY CHANCE POPS TO THE NORTH FRIDAY AND THEN SOUTH ACROSS ALL BUT THE SOUTHWEST SATURDAY...AND EXITING TO THE EAST SATURDAY NIGHT. THE MAIN CONCERN HERE IS THAT THERE WILL PROBABLY BE A CHANCE OF SOME MIXED PRECIPITATION ON THE SOUTHERN PERIPHERY OF THE BAROCLINIC ZONE...WHEREVER IT MAY BE...AND THIS WILL HAVE TO BE MONITORED AS WE GO THROUGH THE WEEK. AS FAR AS TEMPERATURES ARE CONCERNED...WE REMAIN COLD ON TUESDAY AND WEDNESDAY. WIND CHILL HEADLINES WILL PROBABLY BE NEEDED LATE TUESDAY NIGHT INTO WEDNESDAY MORNING OVER THE NORTH CENTRAL. AS THE BAROCLINIC ZONE SHIFTS NORTH WE WARM INTO THE 20S NORTHEAST TO THE 40S SOUTHWEST. THEN FRIDAY THROUGH SUNDAY THE TEMPERATURE GRADIENT SHARPENS EVEN MORE WITH HIGHS IN THE SINGLE DIGITS AND LOW TEENS OVER THE TURTLE MOUNTAINS AREA IN THE NORTH CENTRAL...TO THE MID AND UPPER 40S OVER THE SOUTHWEST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1235 AM CST MON FEB 2 2015 VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF PERIOD. LIGHT SNOW MAY ENTER KISN/KDIK TERMINALS EARLY THIS MORNING AND KBIS BY LATE MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SHORT TERM...AJ LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
340 AM EST MON FEB 2 2015 .SYNOPSIS... LOW PRESSURE EXITING NORTHEAST OF THE AREA...WHIPS COLD FRONT OVERNIGHT/EARLY MONDAY. HIGH PRESSURE CROSSES TUESDAY. NEXT COLD FRONT CROSSES WEDNESDAY NIGHT. HIGH PRESSURE CROSSES FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... LOW PRESSURE CENTER EXITING NORTHEAST OF THE AREA THIS MORNING WITH WIDESPREAD RAIN ACROSS THE LOWLANDS MOVING EAST. EXPECT THE RAIN TO TRANSITION TO ALL SNOW DURING THE MORNING HOURS AS VERY COLD AIR...AS SEEN ON MODELS H85 TEMPERATURES DROPPING FROM 0C TO MINUS 15C THROUGH THE AFTERNOON HOURS. SO...EXPECT A NON DIURNAL TREND IN TEMPERATURES TODAY WITH RAIN CHANGING TO SNOW. STRONG NORTHWEST FLOW WILL TURN ON THE UPSLOPE MACHINE OVER THE NORTHEAST MOUNTAINS LATER TODAY INTO TONIGHT TO PRODUCE SIGNIFICANT SNOW ACCUMULATIONS. SREF PROBABILITIES SHOW 88 PERCENT FOR SNOW ACCUMULATIONS HIGHER THAN 4 INCHES THERE. THE GFS AND ECMWF SUPPORT PCPN UNDER VERY COLD CONDITIONS THROUGH 21Z NORTHEAST MOUNTAINS. THEREFORE...A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR POCAHONTAS...RANDOLPH AND WEBSTER COUNTIES UNTIL 7 PM. IN ADDITION...STRONG GUSTY WINDS COULD PRODUCE BLOWING SNOW LATER THIS AFTERNOON AND TONIGHT OVER THE NORTHEAST MOUNTAINS. THE COMBINATION OF WIND AND VERY COLD TEMPERATURES COULD PRODUCE WIND CHILLS INTO THE MINUS TEENS OVER THE HIGHEST PEAKS THROUGH TONIGHT. TEMPERATURES WILL DROP INTO THE TEENS TONIGHT. WENT WITH THE HRRR AND NAM FOR TEMPERATURES THROUGH THE PERIOD. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A COLD START TO THE MORNING ON TUESDAY BEFORE HIGH PRESSURE MOVES THROUGH THE AREA DURING THE DAY. A PRECIPITATION SHIELD FROM A MORE NORTHERLY SYSTEM WILL EXTEND DOWN TO JUST NORTH OF OUR FORECAST AREA...BUT KEPT OUR AREA DRY FOR NOW. A COLD FRONT SWINGS THROUGH THE AREA ON WED NIGHT INCREASING PRECIPITATION CHANCES ACROSS THE FORECAST AREA WHICH SHOULD BRING LIGHT RAIN IN THE AFTERNOON AND LIGHT SNOW IN THE EVENING. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD EASTERN MID/UPPER LEVEL TROF WITH FAST FLOW...AND FEW OPPORTUNITIES TO ACCESS THE GULF OF MEXICO MOISTURE. WEAK WARM AIR ADVECTION ONGOING TUESDAY NIGHT...WILL TRY TO BRING SOME 20/30 POPS A BIT FASTER SOUTH BY DAWN WEDNESDAY INTO OUR NORTHERN COUNTIES. 12Z GFS A BIT MORE AGGRESSIVE WITH THE MOISTURE MOVING UP THE OHIO VALLEY WEDNESDAY ALONG THAT FRONTAL BOUNDARY. ECMWF CERTAINLY NOT AS MOIST. FOR NOW...WILL KEEP POPS IN CHANCE CATEGORY WITH FRONT WEDNESDAY INTO WEDNESDAY NIGHT. HAVE COLDER AIR BLOWING SOUTH AGAIN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY. WENT COLDER THAN OUR PREVIOUS FORECAST. DRYING AGAIN THURSDAY NIGHT THRU FRIDAY NIGHT. IN THE FAST FLOW...NEXT SYSTEM COULD ARRIVE BY LATE DAY 7. && .AVIATION /09Z MONDAY THROUGH FRIDAY/... LOW PRESSURE EXITING THE AREA TO OUR NORTHEAST WITH A NON DIURNAL TEMPERATURES TREND WARMING OVERNIGHT KEEPING PCPN LIQUID. HOWEVER...BY 12Z MONDAY...VERY COLD TEMPERATURES BEHIND AN ASSOCIATED COLD FRONT WILL RUSH IN SWITCHING ALL PCPN TO SNOW. STARTED WITH VFR CONDITIONS AT MOST PLACES TRANSITIONING TO MVFR AND EVEN IFR SPREADING FROM WEST TO EAST DURING THE OVERNIGHT AND PREDAWN HOURS. ONCE PCPN CHANGES TO SNOW MONDAY MORNING...EXPECT IFR CONDITIONS UNDER SNOW SHOWERS THROUGH MONDAY NIGHT. SOME IMPROVEMENT TO MVFR ACROSS PARTS OF SOUTHEAST OHIO...EASTERN KY...AND WV LOWLANDS EXPECTED AFTER 15Z MONDAY...WITH GRADUAL IMPROVEMENT TO LOW VFR AFTER 22Z. HOWEVER...MVFR AND IFR CEILINGS WILL REMAIN ACROSS THE HIGHER TERRAIN MAINLY NORTHEAST MOUNTAINS AFFECTING EKN THROUGH THE END OF THE TAF PERIOD. IN ADDITION...GUSTY SSW WINDS WILL GRADUALLY SHIFT TO THE SW THEN WEST TO NORTHWEST AFTER 09Z...WITH GUSTS OF UP TO 26 KTS ACROSS THE LOWLANDS...AND UP TO 40 KTS POSSIBLE HIGHER TERRAIN. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIO: TIMING OF DROPS INTO MVFR AND IFR MAY VARY. CONDITIONS MAY IMPROVE TO LOW VFR SLOWER THAN CURRENTLY FORECAST ON MONDAY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. DATE MON 02/02/15 UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19 EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14 CRW CONSISTENCY L L H H M H H H H H H H HTS CONSISTENCY H M H H H H H H H H H H BKW CONSISTENCY L L L L M H H H H H H H EKN CONSISTENCY H L M M M M H H H H M H PKB CONSISTENCY M M M H H H H H H H H H CKB CONSISTENCY L L L L L H H H H H H H AFTER 06Z TUESDAY... IFR CONDITIONS IN SNOW SHOWERS MAY LINGER INTO MONDAY NIGHT IN AND NEAR THE MOUNTAINS OF WV. IFR POSSIBLE IN LIGHT SNOW WEDNESDAY NIGHT INTO THURSDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WINTER WEATHER ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING FOR WVZ038-046-047. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/JW NEAR TERM...ARJ SHORT TERM...JW LONG TERM...KTB AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS PORTLAND OR
851 PM PST SUN FEB 1 2015 .SYNOPSIS...SHOWERS HAVE GENERALLY ENDED FOR THE TIME BEING ACROSS SOUTHWEST WASHINGTON AND NORTHWEST OREGON. HOWEVER THE NEXT IN A SERIES OF FRONTS IS NOT FAR AWAY...AND WILL SPREAD RAIN AND POSSIBLY A COUPLE EMBEDDED THUNDERSTORMS ACROSS THE AREA MONDAY MORNING. RAIN WILL TAPER TO SCATTERED SHOWERS DURING THE DAY...WITH SOME PEEKS OF SUNSHINE POSSIBLE IN THE LOWLANDS BY THE END OF THE DAY. A WARM FRONT WILL LIFT NORTH ACROSS THE FORECAST AREA LATER TUESDAY AND WEDNESDAY...POSSIBLY BRINGING A BIT MORE RAIN AND RISING SNOW LEVELS. MORE ACTIVE WEATHER IS EXPECTED TOWARD THE END OF THE WEEK AS AN ATMOSPHERIC RIVER PATTERN SETS UP OVER THE WEST COAST...WITH HEAVIER RAIN AND THE POTENTIAL FOR STRONG COASTAL WIND THURSDAY THROUGH NEXT WEEKEND. && .SHORT TERM...TONIGHT THROUGH WEDNESDAY...WEAK HIGH PRESSURE IN BETWEEN FRONTAL SYSTEMS HAS TEMPORARILY BROUGHT RAIN TO AN END TONIGHT. SOME PATCHY FOG IS DEVELOPING IN THE COASTAL AND INLAND VALLEYS DUE TO SOME CLEARING AND A VERY MOIST AIR MASS...SO WE ADDED IT TO THE FORECAST FOR TONIGHT. MEANWHILE WATER VAPOR IMAGERY SHOWS ANOTHER FRONTAL SYSTEM LURKING OFFSHORE. THIS SYSTEM IS PRESENTLY BETWEEN 130W-135W...INTERCEPTING A DECENT AMOUNT OF MOISTURE AS IT APPROACHES THE COAST. A PLUME OF 1.0-1.5 INCH PRECIPITABLE WATER VALUES EXTEND NE FROM HAWAII AND INTO THE FRONT UP TO AROUND 42N. A MODEST 100 KT JET IS AIDING IN TRANSPORTING THIS MOISTURE POLEWARD...SO IT APPEARS THE FRONT WILL KEEP A GOOD AMOUNT OF MOISTURE AS IT MOVES ONSHORE MONDAY MORNING. MODEL GUIDANCE HAS BEEN FAIRLY INSISTENT ON KEEPING ENOUGH MOIST INSTABILITY FOR A CHANCE OF THUNDER AS THE FRONT MOVES ONSHORE MONDAY MORNING. AT THIS POINT IT APPEARS THE BEST CHANCE WILL BE IN ELEVATED CONVECTION AHEAD OF THE WARM FRONT OR OCCLUSION MONDAY MORNING. LIGHTNING STRIKES ARE ALREADY BEING OBSERVED WITH THE FRONT OFFSHORE...WE DO NOT REALLY SEE ANY REASON THIS WOULD STOP AS THE FRONT APPROACHES. IN FACT THE 12Z CONVECTIVE-ALLOWING SPC STORM-SCALE ENSEMBLE OF OPPORTUNITY GUIDANCE SHOWS MOST ENSEMBLE MEMBERS ALLOWING SOME 45+ DBZ ECHOES AS THE FRONTAL SYSTEM MOVES ONSHORE MONDAY MORNING...AND THE LAST FEW HRRR RUNS HAVE BEEN SHOWING THE SAME. THE QPF SIGNATURE OF THE 00Z NAM AND 12Z/18Z/00Z GFS SUGGEST EMBEDDED CONVECTION AS WELL. MEANWHILE 00Z MAV GUIDANCE SHOWS 35-45 PCT CHANCE THUNDER 12Z-18Z KSLE SOUTHWARD. THEREFORE DECIDED TO ADD A SLIGHT CHANCE OF THUNDER BACK TO THE FORECAST MONDAY...EXCEPT NOW IT IS EARLY IN THE DAY AND THE FOCUS APPEARS TO BE PORTLAND SOUTHWARD. THE MAIN IMPACT OF ANY CONVECTION WOULD BE TO BRING A PERIOD OF FAIRLY HEAVY RAIN TO THE MONDAY MORNING COMMUTE. RAIN SHOULD TAPER TO SCATTERED SHOWERS FOR THE AFTERNOON...WITH SNOW LEVELS TEMPORARILY LOWERING CLOSE TO THE CASCADE PASSES. HOWEVER THE BULK OF THE PRECIPITATION WILL BE DONE BY THEN...SO ANY SNOW ACCUMULATION SHOULD BE LIGHT EXCEPT FOR THE HIGHEST PEAKS OF THE CASCADES. WITH SOME NVA BEHIND THE MAIN SHORTWAVE...THERE MAY BE ENOUGH SUBSIDENCE FOR A COUPLE SUNBREAKS IN THE VALLEYS MONDAY AFTERNOON...SO WE LOWERED SKY COVER AND POPS A BIT TOWARD THE END OF THE DAY. THE MAIN BAROCLINIC ZONE WILL BE LEFT SOMEWHERE NEAR THE OR/CA BORDER MONDAY NIGHT...AND MODELS ARE COMING INTO SOMEWHAT BETTER AGREEMENT THAT THIS ZONE WILL GRADUALLY LIFT NORTHWARD AS A WARM FRONT TUESDAY AND WEDNESDAY. SHORTWAVES TRAVELLING ALONG THE FRONT WILL PROBABLY KEEP AT LEAST A CHANCE OF RAIN IN THE FORECAST THROUGH MIDWEEK...WITH SNOW LEVELS REMAINING FAIRLY HIGH FOR THE TIME OF YEAR BUT A LITTLE LOWER THAN WHAT WE HAVE BEEN USED TO THE PAST FEW WEEKS. SNOW LEVELS WILL THEN RISE DRAMATICALLY MIDWEEK AS FLOW ALOFT TURNS MORE SOUTHWESTERLY OUT AHEAD OF AN ATMOSPHERIC RIVER WHICH WILL BE TAKING SHAPE OFFSHORE WEDNESDAY AND WEDNESDAY NIGHT. WEAGLE .LONG TERM...WEDNESDAY THROUGH SATURDAY NIGHT...MODELS ARE IN BETTER AGREEMENT FOR WEDNESDAY AND FORECAST AN UPPER RIDGE AMPLIFYING OVER THE AREA AS A DEEPER SHORTWAVE TROUGH APPROACHES THE COAST. THERE APPEARS THAT A WEAK WARM FRONT WILL SLIDE OVER THE AREA FOR LIGHT RAIN DESPITE THE BUILDING RIDGE. THEN A PERIOD OF MUCH WETTER WEATHER IS EXPECTED THURSDAY THROUGH NEXT WEEKEND AS A SWATH OF SUBTROPICAL MOISTURE COMBINED WITH A SERIES OF ATMOSPHERIC WAVES SETS UP OVER THE NE PACIFIC. THIS WEATHER PATTERN WILL LIKELY BRING A SUBSTANTIAL AMOUNT OF RAIN TO PARTS OF THE PACIFIC NORTHWEST. HOWEVER...CONFIDENCE IN TIMING AND AREAS OF PRIMARY QPF FOCUS REMAIN RATHER LOW AT THIS TIME. CURRENT MODELS SHOW THAT THE REALLY HIGH RAINFALL TOTALS WILL SET UP OVER NORTHERN CALIFORNIA...BUT THEY DO NOT ALWAYS FORECAST THESE SITUATIONS VERY WELL...AND WE WILL MONITOR THIS SITUATION CLOSELY FOR THE POTENTIAL OF FLOODING IN THE PORTLAND FORECAST AREA. TJ && .AVIATION...A BIT OF A BREAK IN THE MID AND HIGH CLOUDS HAVE ALLOWED THE LOW CLOUDS TO THICKEN AND DOMINATE CONDITIONS AT THIS TIME. MAINLY MVFR CIGS CENTERED AROUND 015 WITH POCKETS OF IFR 003-007 NEARER THE COAST. ALSO STARTING TO SEE POCKETS OF FOG DEVELOPING AND EXPECT ADDITIONAL TAF AMENDMENTS WILL BE REQUIRED FOR THE NEXT FEW HOURS AS CONFIDENCE IMPROVES AS TO WHICH TERMINALS CLEAR OUT AND ALLOW IT TO FORM. WILL NOT SEE MUCH CHANGE IN THE CIGS OVERNIGHT BUT DO HAVE AN INTERESTING WRINKLE DEVELOPING PER THE STORM SCALE ENSEMBLES (SSEO). THESE CONVECTIVE ALLOWING MODELS ARE BRINGING ISOLATED CONVECTIVE CELLS WITH MODELED REFLECTIVITY IN EXCESS OF 40 DB AND SOME ABOVE 50 DB AT 3000 FEET FROM JUST BEFORE DAYBREAK A LITTLE OFFSHORE THE CENTRAL COAST THROUGH THE MORNING AT NEARER THE CENTRAL CASCADE FOOTHILLS. AS SUCH HAVE ADDED VCTS FOR THE MORNING HOURS AS THIS DATA GIVES CONFIDENCE TO SOME MARGINAL FEELINGS WE WERE HAVING FROM THIS TIME YESTERDAY. THE COLD FRONT WILL SLIDE ACROSS THE REGION FROM THE LATE MORNING THROUGH EARLY EVENING AND BRING PERIODS OF MODERATE RAIN. EXPECT CONTINUED MVFR CIGS AHEAD OF THE FRONT AND LIKELY IFR CIGS FOR THE FEW HOURS SURROUNDING THE FRONTAL PASSAGE. THEN SHOULD SEE SHOWERS AND A RETURN TO BKN MVFR CIGS AND AT WORST VSBYS TOWARDS ABOUT MID EVENING. KPDX AND APPROACHES...MVFR CIGS BETWEEN 1000 AND 1500 FT WILL PERSIST FOR THE BULK OF THE NEXT 24 HOURS...THOUGH COULD SEE CIGS LOWER BELOW 1000 FT IN FOG/LOW STRATUS OVERNIGHT FROM 06Z-12Z BUT MORE LIKELY AFTER 18Z AS THE COLD FRONT AND PERIODS OF MODERATE RAIN NEAR. EXPECT COLD FRONTAL PASSAGE OCCURRING NEAR 20-22Z WITH SHOWERS AND MVFR CIGS THEREAFTER. /JBONK && .MARINE...THE LULL BEFORE THE NEXT FRONT WILL BRING SOUTHEAST WINDS ON THE INCREASE AS A COLD FRONT NEARS THE COAST OVERNIGHT. AM SEEING ENOUGH CONCERN FOR INSTABILITY SUCH THAT THUNDERSTORMS ARE POSSIBLE MAINLY AFTER 2 AM TOWARD DAYBREAK AND MAINLY SOUTH OF TILLAMOOK. WINDS REACH SMALL CRAFT ADVISORY CRITERIA WITH GUSTS 25 TO 30 KT AS THE COLD FRONT CROSSES LATE OVERNIGHT WITH STRONGEST GUSTS OVER THE NORTHERN OUTER WATERS. WILL SEE A NOTABLE WIND SHIFT BEHIND THE FRONT MONDAY MORNING WITH GUSTS AROUND 25 KT CONTINUING THROUGH THE AFTERNOON. SEAS WILL BE ON THE INCREASE AS WELL AND CROSS THE 10 FT THRESHOLD AS WIND WAVES PILE ON TOP OF THE SWELL WITH AND SOME TIME AFTER THE FRONTAL PASSAGE. THE FRESH SWELL WILL CONTINUE WELL AFTER THE WINDS AND AT LEAST THROUGH MONDAY EVENING. SEAS MAY LINGER ABOVE 10 FT PAST MIDNIGHT BUT WASN`T COMPLETELY SOLD ON THE IDEA JUST YET. WINDS AND SEAS START TO SUBSIDE MONDAY NIGHT BRINGING SEAS BACK DOWN TO AROUND 7 TO 8 FT BY TUESDAY MORNING AS SHORT-LIVED HIGH PRESSURE BUILDS OVER THE REGION. MODELS ARE IN AGREEMENT THAT AN EVEN STRONGER SYSTEM WILL MOVE ACROSS THE WATERS FROM MID TO LATE WEEK WITH POTENTIAL FOR SOUTHERLY GALES AND SEAS 20-25 FT. HAVE SEEN CONSIDERABLE UNCERTAINTY WITH REGARD TO TIMING BUT LATEST RUNS INDICATE AS EARLY AS WEDNESDAY NIGHT OR AS LATE AS THURSDAY NIGHT/FRIDAY MORNING. /JBONK && .PQR WATCHES/WARNINGS/ADVISORIES... OR...NONE. WA...NONE. PZ...SMALL CRAFT ADVISORY FOR WINDS FROM 1 AM TO 4 PM PST MONDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR HAZARDOUS SEAS FROM 4 AM TO 10 PM PST MONDAY FOR COASTAL WATERS FROM CAPE SHOALWATER WA TO FLORENCE OR OUT 60 NM. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 1 AM TO 6 AM PST MONDAY. SMALL CRAFT ADVISORY FOR ROUGH COLUMBIA RIVER BAR FROM 1 PM TO 7 PM PST MONDAY. && $$ 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 GREENVILLE-SPARTANBURG SC
236 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST OF THE WESTERN CAROLINAS AND NORTHEAST GEORGIA THIS MORNING...USHERING IN COLD AND WINDY CONDITIONS. COOL AND DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE FRONT THROUGH TUESDAY AND LINGER INTO EARLY WEDNESDAY. ANOTHER COLD FRONT WILL MOVE INTO THE AREA FROM THE NORTHWEST ON THURSDAY...WITH DRY HIGH PRESSURE SPREADING BACK OVER THE REGION BY THE END OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 230 AM EST...THE APPROACHING SFC COLD FRONT WAS ANALYZED JUST WEST OF THE SRN APPALACHIANS AT 07Z. FROPA SHOULD OCCUR OVER THE MTNS 09Z THROUGH 12Z...AND GENERALLY EAST OF CLT BY 15Z. THE BEST SRLY LOW LEVEL JET IS ALREADY MOVING EAST OF THE HIGHER TERRAIN...BUT THE SRN MTN WIND ADVISORY WILL BE LEFT IN PLACE FOR CONTINUED GUSTS WITH THE FRONTAL ZONE SHOWERS. CONCERNS FOR THE NEAR TERM FORECAST GOING FORWARD INCLUDE THUNDER POTENTIAL...WIND GUSTS...AND SNOWFALL. ISOLD THUNDER HAS BEEN ADDED TO THE EXTREME SRN/ERN PIEDMONT THROUGH DAYBREAK...WHERE MID 50S DEWPOINTS HAVE SURGED NWD AHEAD OF THE COLD FRONT. SFC TO 1 KM BULK SHEAR REMAINS A ROBUST 40 KT AHEAD OF THE FRONT THIS MORNING...BUT THUS FAR NO SFC BASED CAPE IS SHOWING UP IN THE LATEST LAPS ANALYSIS. HOWEVER...850 TO 500 MB LAPSE RATES IN EXCESS OF 6 DEG/KM SHOULD CROSS THE PIEDMONT AROUND DAYBREAK...WHICH SUPPORTS THE ISOLD THUNDER MENTION JUST AHEAD OF THE FRONT. DEEP LAYER DPVA WILL CROSS THE REGION MAINLY AROUND 12Z...WITH A MID LEVEL DRY SLOT WRAPPING IN VERY QUICKLY FROM THE SW 12Z TO 15Z. WINDS WILL COME UP RAPIDLY IN THE COLD ADVECTION POST FROPA FLOW...AND UPSLOPE MOISTURE WILL INCREASE SNOW SHOWER RATES OVER THE WRN MTNS. THE CURRENT WINTER WEATHER AND WIND ADVISORIES LOOK WELL PLACED FOR THE MOST PART...WITH HIGH ELEVATION SNOW ACCUMS OF 1 TO 3 INCHES TODAY...VERY LITTLE IN THE VALLEYS...AND WIND GUSTS OF 40 TO 50 MPH LIKELY. THE MAIN ADJUSTMENT WILL BE TO EXPAND THE WIND ADVISORY OUT OVER THE NC FOOTHILLS WHERE RAP PROFILES SUGGEST 45 KT AT THE TOP OF THE MIXED LAYER THROUGH THE AFTN HOURS. A HIGH WIND WARNING WAS CONTEMPLATED FOR THE NRN MTNS...BUT RECENT EVENTS WITH 50 KT MODEL INDICATED 850 MB JETS HAVE FAILED TO PRODUCE DAMAGE...AND DEEP LAYER SUBSIDENCE MAY BE CURTAILED BY AN INVERSION ALOFT. NW FLOW MOISTURE AT LOW LEVELS WILL DRY UP QUICKLY THIS EVENING. EXPECT WESTERLY FLOW ALOFT AHEAD OF THE NEXT SWIFTLY MOVING BUT SHALLOW CLIPPER WAVE TONIGHT. MIN TEMPS WILL FALL INTO THE TEENS AND 20S ACROSS THE REGION. BLACK ICE CONCERNS WILL CONTINUE IN THE MTNS. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... AS OF 130 AM MONDAY...SFC HIGH PRESSURE WILL DOMINATE OVER THE SOUTHEAST TUE. A FAST MOVING SHORTWAVE WILL CROSS THE AREA EARLY IN THE DAY BUT WITH LITTLE MOISTURE TO WORK WITH...ONLY A FEW HIGH CLOUDS ARE EXPECTED TO RESULT FROM ITS PASSAGE. OTHERWISE ZONAL FLOW WILL CONTINUE OVER THE UPLAND SOUTH THRU TUE NIGHT...HEIGHTS THEN FALLING OVER THE MISSISSIPPI VALLEY WED WITH ANOTHER ARCTIC COLD FRONT DIVING INTO THAT AREA. THE HIGH SHIFTS EWD AND OFFSHORE WED IN RESPONSE...ALLOWING RETURN FLOW AND INCREASING THICKNESSES. OUR WEATHER WILL REMAIN DRY DURING THE PERIOD. MAX TEMPS TUE WILL BE A FEW DEGREES BELOW DAILY NORMALS...WITH NEAR NORMAL MINS WED MRNG. MAXES RISE TO A LITTLE ABOVE NORMAL FOR WED. DEWPOINTS WILL REMAIN ON THE LOW SIDE...PERHAPS MAKING FOR UNCOMFORTABLY DRY CONDITIONS. HOWEVER RH DOES NOT LOOK TO DROP BELOW CRITICAL LEVELS FOR FIRE WX. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 220 AM MONDAY...AT 00Z THURSDAY A COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST AND A LOW WILL BE TRACKING EAST ACROSS THE GULF TOWARD FLORIDA. MOISTURE ASSOCIATED WITH THE FRONT IS RATHER SPARSE... ESPECIALLY ACCORDING TO THE ECMWF WHERE IT ONLY REACHES THE MTNS DRYING UP AS IT CROSSES INTO THE FOOTHILLS ON THE EAST SIDE THURSDAY. VARIOUS MODELS HAVE THE GULF LOW PASSING CLOSEST TO OUR AREA THURSDAY MORNING...WITH THE BEST FLUX OF MOISTURE ON THE ECMWF OVER PIEDMONT SECTIONS AROUND 12Z. HIGH PRESSURE BUILDS IN LATE THURSDAY FROM THE NORTHWEST BRINGING BREEZY CONDITIONS UNTIL THE CENTER OF THE HIGH PASSES JUST NORTH OF OUR AREA LATE THURSDAY NIGHT AND ON FRIDAY. THE HIGH SINKS SE TO BE ALIGNED FROM THE FLORIDA PANHANDLE TO THE CAROLINA COAST AT 00Z SATURDAY. THE COOL AIRMASS ASSOCIATED WITH THE HIGH WILL BE MODIFYING FROM A FEW DEGREES BELOW NORMAL ON FRIDAY TO BEING NEAR NORMAL HIGH TEMPS OVER THE WEEKEND. THE NEXT SHORTWAVE WILL BEGIN TO COME OVER THE EASTERN EDGE OF THE BROAD WESTERN UPPER RIDGE AROUND 00Z SUNDAY THEN DIG OVER THE MISSISSIPPI VALLEY BY LATE SUNDAY. THE RESULTING 500MB TROUGH WILL COVER MUCH IF NOT ALL OF THE TERRITORY EAST OF THE MISSISSIPPI RIVER AT 12Z MONDAY. LOWS WILL BE IN THE 30S OVER THE WEEKEND. && .AVIATION /08Z MONDAY THROUGH FRIDAY/... AT KCLT...HEAVIER RAINFALL RATES POISED TO MOVE INTO THE VICINITY OF THE AIRFIELD WILL BRING INCREASED MVFR RESTRICTIONS AS WELL AS TEMPO IFR CIGS LIKELY AFTER 08Z. CONDITIONS MAY THEN ALTERNATE BETWEEN IFR AND MVFR AS STOUT SOUTHERLY FLOW CREATES VARIABLE CEILINGS. GUSTS WILL INCREASE THROUGH MID MORNING...WITH THE COLD FROPA TURNING WINDS WEST THEN NW 14Z TO 17Z...WITH RESTRICTIONS LIFTING. THE AFTN WILL BRING THE PERIOD OF DEEPEST MIXING AND COLD ADVECTION FLOW...WITH WIND GUSTS OF 30 TO 35 KT POSSIBLE AT TIMES...AND ISOLD GUSTS EVEN HIGHER. WINDS WILL ABATE THROUGH THE EVENING HOURS. AT KAVL...GUSTY SRLY WINDS WILL QUICKLY TURN NW WITH FROPA 10Z THIS MORNING. CIGS WILL BE QUITE VARIABLE...WITH IFR POSSIBLE AT TIMES DURING THE BETTER SHOWERS...AND THEN STEADIER MVFR DURING THE PEAK NW FLOW THROUGH MIDDAY. A FEW SNOW SHOWERS COULD APPROACH THE AIRFIELD DURING THE PEAK OF THE NW FLOW MOISTURE...BUT THE CHANCES ONLY WARRANT A VCSH MENTION AT PRESENT. GUSTS TO 35 KT WILL BE COMMON TODAY...AND SOME GUSTS ABOVE 40 KT CANNOT BE RULED OUT. THE GRADIENT SLOWLY RELAXES THIS EVENING. ELSEWHERE...CIGS WILL LIKELY VARY BETWEEN IFR AND MVFR AT THE FOOTHILL TAF SITES IN THE STOUT SOUTHERLY WINDS AND VARIABLE SHOWER RATES AHEAD OF THE FRONTAL ZONE. FROPA FROM 12Z TO 14Z THIS MORNING WILL TURN WINDS W THEN NW...WITH GUSTS ABOVE 30 KT LIKELY AT TIMES TODAY...AND PERHAPS NEAR 40 KT CLOSER TO KHKY THIS AFTN. RESTRICTIONS WILL QUICKLY LIFT THROUGH MID MORNING. WINDS WILL ABATE THIS EVENING. OUTLOOK...VFR CONDITIONS ARE EXPECTED THROUGH MID WEEK. ANOTHER MOIST LOW PRESSURE SYSTEM/COLD FRONT MAY AFFECT THE REGION THU INTO FRI. CONFIDENCE TABLE... 07-13Z 13-19Z 19-01Z 01-06Z KCLT MED 78% HIGH 96% HIGH 100% HIGH 100% KGSP MED 66% HIGH 96% HIGH 100% HIGH 100% KAVL HIGH 80% MED 71% HIGH 100% MED 76% KHKY MED 71% HIGH 94% HIGH 100% HIGH 100% KGMU MED 69% HIGH 96% HIGH 100% HIGH 100% KAND MED 72% HIGH 83% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR GAZ010. NC...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR NCZ033- 048>053-058-059-062-063. WIND ADVISORY UNTIL 5 AM EST EARLY THIS MORNING FOR NCZ048-051- 052-058-059-062>064. WIND ADVISORY FROM 7 AM THIS MORNING TO 7 PM EST THIS EVENING FOR NCZ035-064-065-501>507-509. SC...NONE. && $$ SYNOPSIS...HG NEAR TERM...HG SHORT TERM...WIMBERLEY LONG TERM...DEO AVIATION...HG
AREA FORECAST DISCUSSION
NWS AMARILLO TX
318 AM CST MON FEB 2 2015 .DISCUSSION... EARLY THIS MORNING 11-3.9 IR AND SURFACE OBS SHOWED PERSISTENT STRATUS ACROSS MAINLY THE WESTERN HALF OF THE AREA. SURFACE HIGH IN THE WAKE OF DEPARTING SHORTWAVE NOW OVER THE MID/LOWER MISSISSIPPI VALUE WAS MOVING SOUTHEASTWARD AND SOUTHERLY SURFACE WINDS HAVE INCREASED IN THE WESTERN PORTION OF THE PANHANDLES. WATER VAPOR AND 500 MB RAP ANALYSIS LOOP SHOW PACIFIC MOISTURE STREAMING EASTWARD IN INCREASING MOMENTUM ACROSS THE WESTERN CONUS. AS CROSS MOUNTAIN FLOW STRENGTHENS TODAY SO WILL LEE SIDE SURFACE TROUGH. PRESSURE GRADIENT BETWEEN STRENGTHENING LEE TROUGH AND DEPARTING SURFACE HIGH WILL RESULT IN BREEZY SOUTHWESTERLY WINDS THROUGH AFTERNOON. RISING HEIGHTS AND WARMING ALOFT IN ADDITION TO FULL SUN...MIXING...AND AT LEAST SOMEWHAT OF A DOWNSLOPE COMPONENT TO SURFACE WINDS WILL RESULT IN A WARMING TREND TODAY AND TOMORROW. ATTENTION THEN SHIFTS TO A COLD FRONT THAT WILL PASS THROUGH ON WEDNESDAY. GIVEN TRAJECTORIES FAVORING ONLY A MODESTLY COLD AIR MASS...AM LESS CONCERNED ABOUT SIGNIFICANT FRONTAL TIMING ISSUES THAT ARE TYPICAL OF SHALLOW VERY COLD ARCTIC FRONTS. HAVE THE FRONT MOVING THROUGH FASTER THAN MODEL CONSENSUS BUT NOT QUITE AS FAST AS THE GFS AS THE GFS/GEFS MEAN ARE AN OUTLIER WITH HOW FAST NORTHERN STREAM SHORTWAVE (THAT IS FORCING THIS COLD SURGE) MOVES THROUGH THE MIDWEST COMPARED TO OTHER MODEL GUIDANCE. THIS CHOSEN TIMING IS FAIRLY CONSISTENT WITH THE PREVIOUS FORECAST. THE TIMING THAT WE HAVE AT THIS POINT NECESSITATED A NON-CLIMO DIURNAL CURVE WHICH WAS CONSTRUCTED USING HOURLY TEMPERATURE GRIDS. THIS RESULTS IN A TIGHT GRADIENT IN THE HIGH TEMPERATURE GRID FOR WEDNESDAY. IN FACT...IF THE SLOWER FRONTAL TIMING OCCURS...THE WEST AND ESPECIALLY SOUTHWEST TEXAS PANHANDLE MAY SIGNIFICANTLY EXCEED NORMAL HIGH TEMPERATURES WEDNESDAY AFTERNOON. ADJUSTMENTS ON TEMPERATURES WILL NEED TO BE MADE IN SUBSEQUENT FORECASTS DEPENDING ON FRONTAL TIMING. OTHER SENSIBLE WEATHER CHANGES INCLUDE A GOOD CHANCE OF POST-FRONTAL LOW STRATUS LATE WEDNESDAY LASTING INTO THURSDAY MORNING. THE BEST MOISTURE AND DEEPEST LIFT WILL REMAIN NORTHEAST OF THE AREA AND CHANCES OF MEASURABLE PRECIPITATION LOOK TO BE CONFINED TO PORTIONS OF CENTRAL KANSAS ON WEDNESDAY. KEPT MENTION OF SNOW FLURRIES WITH NON- MEASURABLE LIQUID AMOUNTS IN THE FAR NORTHEAST GIVEN A MODESTLY DEEP SATURATED LAYER IN THE LOW LEVELS BUT CONFIDENCE IN EVEN TRACE AMOUNTS IS NOT PARTICULARLY HIGH. FROM LATE WEEK THROUGH THE WEEKEND THE LARGE SCALE PATTERN FEATURES BUILDING LOW AMPLITUDE RIDGING RESULTING IN ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. FRIDAY AND SATURDAY LOOK TO BE THE WARMEST DAYS WITH MANY LOCATIONS REACHING INTO THE 70S. A PASSING SHORTWAVE TROUGH MAY FORCE A MODEST COOL SURGE INTO THE AREA BY SUNDAY BUT AT THIS POINT IT LOOKS LIKE TEMPERATURES WILL STILL BE ABLE TO RISE TO ABOVE NORMAL LEVELS. BRB && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 55 31 65 34 59 / 0 0 0 0 5 BEAVER OK 51 24 68 30 37 / 0 0 0 0 10 BOISE CITY OK 60 30 66 35 44 / 0 0 0 0 5 BORGER TX 56 32 65 37 51 / 0 0 0 0 5 BOYS RANCH TX 59 27 66 31 51 / 0 0 0 0 5 CANYON TX 56 29 66 33 62 / 0 0 0 0 5 CLARENDON TX 50 30 62 35 56 / 0 0 0 0 5 DALHART TX 58 31 64 34 59 / 0 0 0 0 5 GUYMON OK 56 28 69 33 39 / 0 0 0 0 10 HEREFORD TX 59 28 65 32 62 / 0 0 0 0 5 LIPSCOMB TX 48 29 66 35 41 / 0 0 0 0 10 PAMPA TX 50 30 66 35 47 / 0 0 0 0 5 SHAMROCK TX 45 26 60 35 49 / 0 0 0 0 10 WELLINGTON TX 47 30 61 37 50 / 0 0 0 0 10 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 03/17
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
1100 PM CST SUN FEB 1 2015 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 220 PM CST SUN FEB 1 2015 CONCERNS THROUGH MONDAY... 1. DIMINISHING SNOW/BLOWING SNOW THROUGH THE EVENING 2. NEED FOR WIND CHILL ADVISORY LATE TONIGHT/MONDAY MORNING 3. HIGHS MONDAY CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED RIDGING OVER THE WESTERN U.S....A SHORTWAVE TOPPING THE RIDGE COMING INTO BRITISH COLUMBIA...A DEEP TROUGH OVER THE CENTRAL PLAINS INTO SOUTHERN PORTIONS OF THE FORECAST AREA...AND A SHORTWAVE OVER THE EASTERN DAKOTAS. MID-LEVEL FRONTOGENESIS ASSOCIATED ON THE NORTH SIDE OF THE DEEP TROUGH CONTINUES TO BRING SNOW TO THE SOUTHEASTERN 2/3 OF THE FORECAST AREA. OVER THE NORTHWEST 1/3 AND THROUGH THE REST OF MINNESOTA AND NORTHERN WI...DRIER AND COLDER AIR CONTINUES TO ADVECT SOUTHWARD ON A BRISK NORTHERLY BREEZE. NUMEROUS SITES NORTH OF I-94 REPORTING SURFACE DEWPOINTS BELOW ZERO...AND AS MUCH AS 20 BELOW IN NORTHERN MN. TEMPERATURES TOO WERE IN THE SINGLE DIGITS ABOVE AND BELOW ZERO NORTH OF I-94. CLEARING SKIES REFLECT THE DRIER...COLDER AIR. MAIN 1004MB SURFACE LOW ASSOCIATED WITH THE TROUGH WELL TO OUR SOUTHEAST...JUST EAST OF LINCOLN IL. HOWEVER...A TIGHT PRESSURE GRADIENT EXISTS NORTH OF THIS LOW KEEPING THE BRISK NORTH BREEZE GOING...WITH A 1034MB HIGH OVER THE DAKOTAS. THE SNOW REMAINS ON TRACK TO DIMINISH NORTHWEST TO SOUTHEAST THROUGH THE REST OF THIS AFTERNOON INTO EARLY THIS EVENING. BY 00Z...GOOD MODEL AGREEMENT EXISTS FOR SNOW SOUTHEAST OF A LINE FROM OELWEIN TO TOMAH...AND THEN OUT OF THE FORECAST AREA BY 03Z. ALTHOUGH SNOW IS DIMINISHING...WINDS LOOK TO REMAIN BRISK THROUGH AT LEAST A GOOD PORTION OF THE EVENING. 925MB WINDS AT 00Z RANGE FROM 25-35KT... DROPPING TO 10-25KT AT 06Z. THESE GUSTY WINDS SHOULD KEEP SOME BLOWING AND DRIFTING SNOW GOING AT EXPOSED LOCATIONS...EVEN WHEN THE SNOW ENDS...THUS HAVE DECIDED TO HOLD OFF CANCEL ANY HAZARDS AT THIS TIME. HOWEVER...ITS POSSIBLE SOME AREAS MAY GET CANCELLED EARLY OVER THE NEXT FEW HOURS SEEING DODGE CENTER HAS IMPROVED TO 10 MILE VISIBILITY ALREADY. DURING THE OVERNIGHT HOURS...THE SHORTWAVE CURRENTLY IN THE EASTERN DAKOTAS IS PROGGED TO CROSS THE FORECAST AREA. ALTHOUGH NO PRECIPITATION PRODUCTION IS EXPECTED WITH THIS SHORTWAVE DUE TO PLENTIFUL DRY AIR AROUND AND AHEAD OF IT...THE SHORTWAVE WILL HELP TO BRING THE DAKOTAS SURFACE RIDGE INTO THE FORECAST AREA...THUS DIMINISHING THE WINDS AND CLEARING THE SKIES OUT. WITH THE FRESH SNOW COVER...TEMPERATURES COULD REALLY PLUMMET...AIDED TOO BY 925MB TEMPS FALLING TO -16 TO -18C. WOULD NOT BE SURPRISED TO SEE A FEW READINGS OF 10 BELOW...WHICH WOULD MOST LIKELY OCCUR NEAR AUSTIN MN AND IN TAYLOR COUNTY WI. DESPITE THE COLD READINGS...WIND CHILLS SHOULD STAY UP JUST ABOVE THE -20F THRESHOLD FOR AN ADVISORY. A MUCH QUIETER BUT COLD DAY ON TAP FOR MONDAY AS THE SURFACE RIDGE CROSSES THE FORECAST AREA. THE SURFACE RIDGE GRADUALLY CROSSES THE FORECAST AREA...WITH MOSTLY SUNNY SKIES TO START. SHOULD SEE SOME INCREASE IN CLOUDS IN THE AFTERNOON AS THE SHORTWAVE COMING INTO BRITISH COLUMBIA DROPS DOWN INTO THE SIOUX FALLS AREA BY 00Z. 925MB TEMPS DONT START WARMING UNTIL LATE IN THE DAY...AND WITH FRESH SNOW...HIGHS ONLY LOOK TO TOP OUT IN THE LOW TO MID TEENS. ITS POSSIBLE SOME LOCATIONS IN NORTHEAST IOWA ONLY REACH THE SINGLE DIGITS ABOVE ZERO AS SUGGESTED BY THE 01.12Z ECMWF/CANADIAN. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 220 PM CST SUN FEB 1 2015 LONG TERM CONCERNS... 1. BRIEF LIGHT SNOW MAKER MONDAY EVENING FOR MAINLY NORTHEAST IOWA 2. ANOTHER LIGHT SNOW MAKER FOR TUESDAY AFTERNOON/EVENING...MAINLY SOUTH OF I-90 3. POSSIBLE WIND CHILL ADVISORY FOR THURSDAY MORNING 4. POSSIBILITY FOR A BRIEF WARM UP...BUT BREEZY...FOR FRIDAY INTO SATURDAY. SHORTWAVE OVER BRITISH COLUMBIA IS PROGGED TO DIG INTO SOUTHEAST IOWA AND NORTHEAST MO BY 06Z TUESDAY. THIS TRACK HAS TRENDED SOUTHWEST SLIGHTLY OVER THE PAST FEW DAYS. DESPITE ITS POTENT NATURE/LOOK...MODELS DO NOT PRODUCE MUCH QPF WITH IT DUE TO DRY AIR IN PLACE FROM MONDAY...WITH THE GFS ENTIRELY DRY. GIVEN ITS STRENGTH FEEL THE NEED TO INCLUDE A LOW PRECIPITATION CHANCE FOR MONDAY EVENING...SIMILAR TO THE PREVIOUS FORECAST. HOWEVER...WITH THE SOUTHWEST TREND IN THE GUIDANCE...SHIFTED THE CHANCES A LITTLE MORE SOUTHWEST AS WELL. SHOULD ANY SNOW OCCUR...MAYBE A FEW TENTHS ACCUMULATE. AFTER A QUIET OVERNIGHT MONDAY NIGHT INTO TUESDAY MORNING...POSSIBLY A BIT COOL WITH A SURFACE RIDGE CROSSING...ANOTHER SHORTWAVE TROUGH COMING TROUGH NORTHWEST FLOW IS PROGGED TO AFFECT THE AREA TUESDAY AFTERNOON AND EVENING. THIS SHORTWAVE...ALTHOUGH WEAKER COMPARED TO THE PREVIOUS ONE...HAS A LITTLE MORE MOISTURE TO WORK WITH AND A STRONGER MID LEVEL FRONTOGENESIS ZONE. AS SUCH...01.12Z NAM/GFS/ECMWF/CANADIAN ALL DEVELOP PRECIPITATION...WITH SOME EVEN SHOWING POTENTIAL TO EXCEED 0.10 OF QPF IN 6 HOURS. SOME TRACK ISSUES AGAIN EXIST...WITH THE STRONGEST CONSENSUS FOR THE SNOW TO MOVE THROUGH LOCATIONS SOUTH OF I-90. UNLESS THE SHORTWAVE BECOMES STRONGER IN LATER RUNS...FEEL THE PLACEMENT OF THIS SNOW SHOULD STAY PERSISTENT. THUS...DID RAISE PRECIPITATION CHANCES TOWARDS 50 ACROSS NORTHEAST IA/FAR SOUTHWEST WI. MAY END UP ACCUMULATING 1-2 INCHES. SOME CONCERN TOO FOR THE PRECIPITATION TO END AS FREEZING DRIZZLE AS ICE IS LOST ALOFT...BUT ITS VERY POSSIBLE THE PRECIPITATION ENDS TOO ONCE WE LOSE THE ICE. THEREFORE...HAVE YET TO INTRODUCE THIS INTO THE FORECAST. SOMETHING TO MONITOR. A STRONG UPPER TROUGH DROPS INTO THE REGION ON WEDNESDAY. THERE COULD BE A LITTLE LIGHT SNOW IN OUR SOUTH DURING THE AFTERNOON WITH ANOTHER FRONTOGENESIS BAND SETTING UP ACROSS IOWA AND ILLINOIS. HOWEVER...THE MORE SIGNIFICANT PART IS THE ARCTIC AIR ACCOMPANY THE UPPER TROUGH. 925MB TEMPS PLUMMET FROM -10 TO -13C AT 12Z WEDNESDAY TO -18 TO -20C AT 12Z THURSDAY. A SOMEWHAT BRISK NORTHERLY BREEZE IS PROGGED WEDNESDAY AFTERNOON AND EVENING BEFORE DIMINISHING OVERNIGHT. THIS DIMINISHING COULD KEEP US JUST OUT OF A WIND CHILL ADVISORY NEED FOR THURSDAY MORNING...BUT TEMPERATURES WOULD TANK INSTEAD...ESPECIALLY IF SKIES ARE CLEAR. STAYED ON THE COOLER SIDE OF GUIDANCE FOR LOWS WEDNESDAY NIGHT GIVEN THIS REGIME AND THINKING ARCTIC AIR COMING IN WILL CLEAR SKIES OUT. THE UPPER TROUGH IS FAST MOVING SUCH THAT WEAK UPPER RIDGING COMES IN BY THURSDAY AFTERNOON...WITH NORTHWEST FLOW PERSISTING BEYOND INTO SUNDAY. THUS...AFTER THE COLD START THURSDAY MORNING WE WILL BE ON THE WARMING TREND HEADING INTO FRIDAY AND SATURDAY. STILL A LOT OF SPREAD AMONGST ECMWF GUIDANCE REGARDING THE HIGHS FRIDAY AND SATURDAY...BUT GENERAL TREND SHOULD BRING HIGHS BACK TO NORMAL. GFS/ECMWF 925MB WINDS ALSO INCREASE TO 20-40KT ON FRIDAY...THUS SUGGESTING IT COULD BE A BIT BREEZY. SOMETHING WELL HAVE TO WATCH HEADING INTO NEXT WEEKEND IS A FRONTOGENETIC ZONE DROPPING SOUTHWEST THROUGH THE FORECAST AREA. ACTUAL POSITION AND TIMING HAS VARIED SOMEWHAT...REQUIRING LOW CHANCES OF PRECIPITATION THROUGH THE WEEKEND. NEVERTHELESS...COULD SEE A COUPLE INCHES OF SNOW ACCUMULATION. COOLER AIR FOLLOWS IN THE WAKE OF THIS ZONE FOR SUNDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1100 PM CST SUN FEB 1 2015 SKIES HAVE CLEARED AND EXPECT VFR CONDITIONS THROUGH THE BETTER PART OF MONDAY. WINDS HAVE ALSO BEEN DECREASING AS THE LOW EXITS EAST...HIGH PRESSURE APPROACHES...AND THE PRESSURE GRADIENT SLACKENS. VARIABLE WINDS IN THE MORNING WILL BECOME SOUTHERLY BY 18Z MONDAY. UPPER LEVEL SHORTWAVE TROUGH SLATED TO SPIN ACROSS IOWA MONDAY NIGHT...LIKELY BRINGING A LITTLE LIGHT SNOW. CURRENT TRACK WOULD KEEP THE BULK OF ANY -SN SOUTHWEST OF KRST/KLSE...BUT WOULD BRING AT LEAST SOME LOW/MID LEVEL CIGS. MVFR IS POSSIBLE - MORESO OVERNIGHT. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...RIECK
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
545 AM MST MON FEB 2 2015 .UPDATE... UPDATED WATCHES/WARNINGS/ADVISORIES SECTION. && .SYNOPSIS... ANTICIPATE PATCHY FOG OVER SOME AREAS THIS MORNING...MAINLY THE CENTRAL ARIZONA DESERTS...BUT NOT NEARLY AS WIDESPREAD AS YESTERDAY. HIGH PRESSURE WILL SLOWLY BUILD INLAND ACROSS THE DESERT SOUTHWEST BRINGING DRY WEATHER AND A WARMING TREND...ALONG WITH MOSTLY CLEAR SKIES THROUGH THE UPCOMING WEEK. HIGHS WILL APPROACH 80 DEGREES IN LOWER DESERTS COMMUNITIES BY THE END OF THE WEEK. && .DISCUSSION... WITH LINGERING SURFACE MOISTURE AND ONLY MINOR CIRRUS...FOG DEVELOPMENT REMAINS A POSSIBILITY. IN FACT...TEMP/DEW POINT SPREADS EARLY THIS MORNING OVER SOUTH-CENTRAL ARIZONA AREA RUNNING SIMILARLY TO 24 HOURS AGO AT LESS URBAN LOCATIONS. HOWEVER...DRIER AIR ABOVE THE SURFACE SHOULD PREVENT DENSE FOG DEVELOPMENT FROM BEING AS WIDESPREAD AS YESTERDAY. OF NOTE...MODEL FORECAST SOUNDINGS HAVE UNDERINITIALIZED THE SURFACE DEW POINTS...ESPECIALLY THE GFS...BUT THEY ALSO DEPICT MORE COOLING THAN HAS BEEN SEEN SO FAR. AS OF THIS WRITING...THE LOWEST VISIBILITIES REPORTED IN THE METARS HAVE BEEN 7-8 MILES. LAST NIGHT AT THIS TIME...LOW VISIBILITIES HAD ALREADY BEGUN. HRRR CONTINUES TO DEPICT DENSE FOG DEVELOPMENT OVER MAINLY THE SAME AREA AS YESTERDAY BUT IT IS STARTING WITH VISIBILITIES THAT ARE TOO LOW. WILL CONTINUE TO MONITOR BUT FOR NOW WILL HOLD OFF ON ISSUING A DENSE FOG ADVISORY. IF DENSE FOG DEVELOPS IN OUR AREA...MOST LIKELY LOCATION WILL BE PINAL COUNTY. LOOKING AT THE BIG PICTURE...TROUGHING COVERS MUCH OF CANADA AND THE EASTERN HALF OF THE CONUS. THERE IS ALSO TROUGHING OVER THE NORTHEAST PACIFIC...AND A HIGH LATITUDE UPPER HIGH TO THE NORTHWEST. IN BETWEEN THE TROUGHING REGIONS IS A RIDGE WITH AN AXIS NEAR THE WEST COAST. THIS PATTERN WILL CONTINUE FOR MUCH OF THIS WEEK WITH A SLOW EASTWARD ADVANCE OF THE RIDGE AND ACCORDINGLY A SLOW WARMING TREND. SYSTEMS BEING EJECTED FROM THE PACIFIC TROUGH WILL MOVE THROUGH THE PACIFIC NORTHWEST AND TRACK WELL NORTH OF OUR FORECAST AREA. LATE IN THE WEEK...THE PATTERN BEGINS TO CHANGE WITH A TEMPORARY FLATTENING OF THE RIDGE BEFORE IT REBOUNDS EARLY NEXT WEEK. THERE WILL BE SOME CIRRUS FROM TIME TO TIME...THICKEST IN THE FRIDAY/SATURDAY TIME FRAME. MADE SOME SUBTLE DOWNWARD ADJUSTMENTS TO PREVIOUS TEMP FORECASTS TO ACCOUNT FOR A SLOWER ARRIVAL OF THE RIDGE AXIS. HOWEVER...80 DEGREE MAX TEMPS STILL IN SIGHT ON SOME OF THE LOWER DESERTS DURING THE LATTER HALF OF THE WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL... PATCHY FOG IS FORMING ON THE SOUTHEASTERN OUTSKIRTS OF TOWN AS OF 11Z...ALTHOUGH COVERAGE/DENSITY NOWHERE NEAR AS BAD AS YESTERDAY. AT THIS POINT IT LOOKS LIKE KIWA WOULD BE THE HARDEST HIT AND I WILL TAKE VSBYS DOWN TO IFR FOR A BRIEF TIME AROUND DAYBREAK. VERY LOW CONFIDENCE IN KIWA VSBY FORECAST...WILL NEED TO ASSESS HOW BAD FOG IS AFTER SUNRISE. ELSEWHERE AT KPHX/KSDL...LOCAL WEBCAMS ONLY SHOWING A LIGHT HAZE AROUND 6SM. MEANWHILE THICKENING HIGH CLOUDS CONTINUE TO APPROACH FROM THE NORTHWEST...CERTAINLY HELPING TO PREVENT WIDESPREAD DENSE FOG FORMATION. FORECAST SOUNDINGS SUGGEST TEMPS/DEWPOINTS WILL CONTINUE TO DROP IN TANDEM WITH A BRIEF DROP IN VSBYS TO 3-4SM AROUND 13Z...WILL CONTINUE WITH THIS THINKING WITH THE 12Z TAF ISSUANCE. AS FOR WINDS...LIGHT EAST WINDS AT 5KTS OR LESS AT KPHX THROUGH LATE MORNING BEFORE THE TYPICAL WESTERLY SHIFT EARLY AFTERNOON. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA WITH ONLY OCCASIONAL CIRRUS CLOUDS THROUGH MONDAY AFTERNOON. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE UNDER A WEAK PRESSURE GRADIENT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... WEDNESDAY THROUGH SUNDAY... WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS FOLLOWING THE TYPICAL DIURNAL PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...DENSE FOG ADVISORY UNTIL 10 AM THIS MORNING FOR AZZ028. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...AJ AVIATION...LEINS FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION...UPDATED
NWS PHOENIX AZ
405 AM MST MON FEB 2 2015 .UPDATE... UPDATED WATCHES/WARNINGS/ADVISORIES SECTION. && .SYNOPSIS... ANTICIPATE PATCHY FOG OVER SOME AREAS THIS MORNING...MAINLY THE CENTRAL ARIZONA DESERTS...BUT NOT NEARLY AS WIDESPREAD AS YESTERDAY. HIGH PRESSURE WILL SLOWLY BUILD INLAND ACROSS THE DESERT SOUTHWEST BRINGING DRY WEATHER AND A WARMING TREND...ALONG WITH MOSTLY CLEAR SKIES THROUGH THE UPCOMING WEEK. HIGHS WILL APPROACH 80 DEGREES IN LOWER DESERTS COMMUNITIES BY THE END OF THE WEEK. && .DISCUSSION... WITH LINGERING SURFACE MOISTURE AND ONLY MINOR CIRRUS...FOG DEVELOPMENT REMAINS A POSSIBILITY. IN FACT...TEMP/DEW POINT SPREADS EARLY THIS MORNING OVER SOUTH-CENTRAL ARIZONA AREA RUNNING SIMILARLY TO 24 HOURS AGO AT LESS URBAN LOCATIONS. HOWEVER...DRIER AIR ABOVE THE SURFACE SHOULD PREVENT DENSE FOG DEVELOPMENT FROM BEING AS WIDESPREAD AS YESTERDAY. OF NOTE...MODEL FORECAST SOUNDINGS HAVE UNDERINITIALIZED THE SURFACE DEW POINTS...ESPECIALLY THE GFS...BUT THEY ALSO DEPICT MORE COOLING THAN HAS BEEN SEEN SO FAR. AS OF THIS WRITING...THE LOWEST VISIBILITIES REPORTED IN THE METARS HAVE BEEN 7-8 MILES. LAST NIGHT AT THIS TIME...LOW VISIBILITIES HAD ALREADY BEGUN. HRRR CONTINUES TO DEPICT DENSE FOG DEVELOPMENT OVER MAINLY THE SAME AREA AS YESTERDAY BUT IT IS STARTING WITH VISIBILITIES THAT ARE TOO LOW. WILL CONTINUE TO MONITOR BUT FOR NOW WILL HOLD OFF ON ISSUING A DENSE FOG ADVISORY. IF DENSE FOG DEVELOPS IN OUR AREA...MOST LIKELY LOCATION WILL BE PINAL COUNTY. LOOKING AT THE BIG PICTURE...TROUGHING COVERS MUCH OF CANADA AND THE EASTERN HALF OF THE CONUS. THERE IS ALSO TROUGHING OVER THE NORTHEAST PACIFIC...AND A HIGH LATITUDE UPPER HIGH TO THE NORTHWEST. IN BETWEEN THE TROUGHING REGIONS IS A RIDGE WITH AN AXIS NEAR THE WEST COAST. THIS PATTERN WILL CONTINUE FOR MUCH OF THIS WEEK WITH A SLOW EASTWARD ADVANCE OF THE RIDGE AND ACCORDINGLY A SLOW WARMING TREND. SYSTEMS BEING EJECTED FROM THE PACIFIC TROUGH WILL MOVE THROUGH THE PACIFIC NORTHWEST AND TRACK WELL NORTH OF OUR FORECAST AREA. LATE IN THE WEEK...THE PATTERN BEGINS TO CHANGE WITH A TEMPORARY FLATTENING OF THE RIDGE BEFORE IT REBOUNDS EARLY NEXT WEEK. THERE WILL BE SOME CIRRUS FROM TIME TO TIME...THICKEST IN THE FRIDAY/SATURDAY TIME FRAME. MADE SOME SUBTLE DOWNWARD ADJUSTMENTS TO PREVIOUS TEMP FORECASTS TO ACCOUNT FOR A SLOWER ARRIVAL OF THE RIDGE AXIS. HOWEVER...80 DEGREE MAX TEMPS STILL IN SIGHT ON SOME OF THE LOWER DESERTS DURING THE LATTER HALF OF THE WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL... PATCHY FOG IS FORMING ON THE SOUTHEASTERN OUTSKIRTS OF TOWN AS OF 11Z...ALTHOUGH COVERAGE/DENSITY NOWHERE NEAR AS BAD AS YESTERDAY. AT THIS POINT IT LOOKS LIKE KIWA WOULD BE THE HARDEST HIT AND I WILL TAKE VSBYS DOWN TO IFR FOR A BRIEF TIME AROUND DAYBREAK. VERY LOW CONFIDENCE IN KIWA VSBY FORECAST...WILL NEED TO ASSESS HOW BAD FOG IS AFTER SUNRISE. ELSEWHERE AT KPHX/KSDL...LOCAL WEBCAMS ONLY SHOWING A LIGHT HAZE AROUND 6SM. MEANWHILE THICKENING HIGH CLOUDS CONTINUE TO APPROACH FROM THE NORTHWEST...CERTAINLY HELPING TO PREVENT WIDESPREAD DENSE FOG FORMATION. FORECAST SOUNDINGS SUGGEST TEMPS/DEWPOINTS WILL CONTINUE TO DROP IN TANDEM WITH A BRIEF DROP IN VSBYS TO 3-4SM AROUND 13Z...WILL CONTINUE WITH THIS THINKING WITH THE 12Z TAF ISSUANCE. AS FOR WINDS...LIGHT EAST WINDS AT 5KTS OR LESS AT KPHX THROUGH LATE MORNING BEFORE THE TYPICAL WESTERLY SHIFT EARLY AFTERNOON. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA WITH ONLY OCCASIONAL CIRRUS CLOUDS THROUGH MONDAY AFTERNOON. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE UNDER A WEAK PRESSURE GRADIENT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... WEDNESDAY THROUGH SUNDAY... WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS FOLLOWING THE TYPICAL DIURNAL PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...DENSE FOG ADVISORY UNTIL 10 AM THIS MORNING FOR AZZ028. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...AJ AVIATION...LEINS FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION...CORRECTED TYPO
NWS PHOENIX AZ
320 AM MST MON FEB 2 2015 .SYNOPSIS... ANTICIPATE PATCHY FOG OVER SOME AREAS THIS MORNING...MAINLY THE CENTRAL ARIZONA DESERTS...BUT NOT NEARLY AS WIDESPREAD AS YESTERDAY. HIGH PRESSURE WILL SLOWLY BUILD INLAND ACROSS THE DESERT SOUTHWEST BRINGING DRY WEATHER AND A WARMING TREND...ALONG WITH MOSTLY CLEAR SKIES THROUGH THE UPCOMING WEEK. HIGHS WILL APPROACH 80 DEGREES IN LOWER DESERTS COMMUNITIES BY THE END OF THE WEEK. && .DISCUSSION... WITH LINGERING SURFACE MOISTURE AND ONLY MINOR CIRRUS...FOG DEVELOPMENT REMAINS A POSSIBILITY. IN FACT...TEMP/DEW POINT SPREADS EARLY THIS MORNING OVER SOUTH-CENTRAL ARIZONA AREA RUNNING SIMILARLY TO 24 HOURS AGO AT LESS URBAN LOCATIONS. HOWEVER...DRIER AIR ABOVE THE SURFACE SHOULD PREVENT DENSE FOG DEVELOPMENT FROM BEING AS WIDESPREAD AS YESTERDAY. OF NOTE...MODEL FORECAST SOUNDINGS HAVE UNDERINITIALIZED THE SURFACE DEW POINTS...ESPECIALLY THE GFS...BUT THEY ALSO DEPICT MORE COOLING THAN HAS BEEN SEEN SO FAR. AS OF THIS WRITING...THE LOWEST VISIBILITIES REPORTED IN THE METARS HAVE BEEN 7-8 MILES. LAST NIGHT AT THIS TIME...LOW VISIBILITIES HAD ALREADY BEGUN. HRRR CONTINUES TO DEPICT DENSE FOG DEVELOPMENT OVER MAINLY THE SAME AREA AS YESTERDAY BUT IT IS STARTING WITH VISIBILITIES THAT ARE TOO LOW. WILL CONTINUE TO MONITOR BUT FOR NOW WILL HOLD OFF ON ISSUING A DENSE FOG ADVISORY. IF DENSE FOG DEVELOPS IN OUR AREA...MOST LIKELY LOCATION WILL BE PINAL COUNTY. LOOKING AT THE BIG PICTURE...TROUGHING COVERS MUCH OF CANADA AND THE EASTERN HALF OF THE CONUS. THERE IS ALSO TROUGHING OVER THE NORTHEAST PACIFIC...AND A HIGH LATITUDE UPPER HIGH TO THE NORTHWEST. IN BETWEEN THE TROUGHING REGIONS IS A RIDGE WITH AN AXIS NEAR THE WEST COAST. THIS PATTERN WILL CONTINUE FOR MUCH OF THIS WEEK WITH A SLOW EASTWARD ADVANCE OF THE RIDGE AND ACCORDINGLY A SLOW WARMING TREND. SYSTEMS BEING EJECTED FROM THE PACIFIC TROUGH WILL MOVE THROUGH THE PACIFIC NORTHWEST AND TRACK WELL NORTH OF OUR FORECAST AREA. LATE IN THE WEEK...THE PATTERN BEGINS TO CHANGE WITH A TEMPORARY FLATTENING OF THE RIDGE BEFORE IT REBOUNDS EARLY NEXT WEEK. THERE WILL BE SOME CIRRUS FROM TIME TO TIME...THICKEST IN THE FRIDAY/SATURDAY TIME FRAME. MADE SOME SUBTLE DOWNWARD ADJUSTMENTS TO PREVIOUS TEMP FORECASTS TO ACCOUNT FOR A SLOWER ARRIVAL OF THE RIDGE AXIS. HOWEVER...80 DEGREE MAX TEMPS STILL IN SIGHT ON SOME OF THE LOWER DESERTS DURING THE LATTER HALF OF THE WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL... SHORT TERM: MOSTLY CLEAR SKIES WILL PREVAIL TONIGHT. SFC WINDS HAVE ALREADY TURNED E/SE AT KPHX (AND LIGHT AND VARIABLE ELSEWHERE) AND WILL MAINTAIN THESE HEADINGS THROUGH THE NIGHT WITH SPEEDS 3-5KT OR LESS. MONDAY MORNING: POTENTIAL STILL EXISTS FOR SOME FOG AROUND PHOENIX TERMINALS MONDAY MORNING...HOWEVER SHORT TERM HIGH RESOLUTION MODEL TRENDS SUGGEST FAR MORE LIMITED COVERAGE...AND DENSE FOG STAYING SOUTH OF THE METRO AREA. STILL MODERATE CONFIDENCE OF BRIEF PERIOD OF MVFR VSBY IN SE MARICOPA COUNTY (INCLUDING KPHX)...WITH FAR LESS CONFIDENCE OF LOWER CATEGORIES. MOST LIKELY TIMING WOULD BE IN THE 11Z-15Z TIME FRAME. OTHERWISE...EAST WINDS 3-6KT WILL PREVAIL INTO MONDAY AFTERNOON...THOUGH SOMEWHAT STRONGER WINDS UP TO 12KT WILL BE POSSIBLE IN A 1500-2000FT LAYER. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA WITH ONLY OCCASIONAL HIGH CIRRUS CLOUDS THROUGH MONDAY AFTERNOON. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE UNDER A WEAK PRESSURE GRADIENT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... TUESDAY THROUGH SATURDAY... WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS FOLLOWING THE TYPICAL DIURNAL PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...AJ AVIATION...MO FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS PHOENIX AZ
320 AM MST SUN FEB 1 2015 .SYNOPSIS... ANTICIPATE PATCHY FOG OVER SOME AREAS THIS MORNING...MAINLY THE CENTRAL ARIZONA DESERTS...BUT NOT NEARLY AS WIDESPREAD AS YESTERDAY. HIGH PRESSURE WILL SLOWLY BUILD INLAND ACROSS THE DESERT SOUTHWEST BRINGING DRY WEATHER AND A WARMING TREND...ALONG WITH MOSTLY CLEAR SKIES THROUGH THE UPCOMING WEEK. HIGHS WILL APPROACH 80 DEGREES IN LOWER DESERTS COMMUNITIES BY THE END OF THE WEEK. && .DISCUSSION... WITH LINGERING SURFACE MOISTURE AND ONLY MINOR CIRRUS...FOG DEVELOPMENT REMAINS A POSSIBILITY. IN FACT...TEMP/DEW POINT SPREADS EARLY THIS MORNING OVER SOUTH-CENTRAL ARIZONA AREA RUNNING SIMILARLY TO 24 HOURS AGO AT LESS URBAN LOCATIONS. HOWEVER...DRIER AIR ABOVE THE SURFACE SHOULD PREVENT DENSE FOG DEVELOPMENT FROM BEING AS WIDESPREAD AS YESTERDAY. OF NOTE...MODEL FORECAST SOUNDINGS HAVE UNDERINITIALIZED THE SURFACE DEW POINTS...ESPECIALLY THE GFS...BUT THEY ALSO DEPICT MORE COOLING THAN HAS BEEN SEEN SO FAR. AS OF THIS WRITING...THE LOWEST VISIBILITIES REPORTED IN THE METARS HAVE BEEN 7-8 MILES. LAST NIGHT AT THIS TIME...LOW VISIBILITIES HAD ALREADY BEGUN. HRRR CONTINUES TO DEPICT DENSE FOG DEVELOPMENT OVER MAINLY THE SAME AREA AS YESTERDAY BUT IT IS STARTING WITH VISIBILITIES THAT ARE TOO LOW. WILL CONTINUE TO MONITOR BUT FOR NOW WILL HOLD OFF ON ISSUING A DENSE FOG ADVISORY. IF DENSE FOG DEVELOPS IN OUR AREA...MOST LIKELY LOCATION WILL BE PINAL COUNTY. LOOKING AT THE BIG PICTURE...TROUGHING COVERS MUCH OF CANADA AND THE EASTERN HALF OF THE CONUS. THERE IS ALSO TROUGHING OVER THE NORTHEAST PACIFIC...AND A HIGH LATITUDE UPPER HIGH TO THE NORTHWEST. IN BETWEEN THE TROUGHING REGIONS IS A RIDGE WITH AN AXIS NEAR THE WEST COAST. THIS PATTERN WILL CONTINUE FOR MUCH OF THIS WEEK WITH A SLOW EASTWARD ADVANCE OF THE RIDGE AND ACCORDINGLY A SLOW WARMING TREND. SYSTEMS BEING EJECTED FROM THE PACIFIC TROUGH WILL MOVE THROUGH THE PACIFIC NORTHWEST AND TRACK WELL NORTH OF OUR FORECAST AREA. LATE IN THE WEEK...THE PATTERN BEGINS TO CHANGE WITH A TEMPORARY FLATTENING OF THE RIDGE BEFORE IT REBOUNDS EARLY NEXT WEEK. THERE WILL BE SOME CIRRUS FROM TIME TO TIME...THICKEST IN THE FRIDAY/SATURDAY TIME FRAME. MADE SOME SUBTLE DOWNWARD ADJUSTMENTS TO PREVIOUS TEMP FORECASTS TO ACCOUNT FOR A SLOWER ARRIVAL OF THE RIDGE AXIS. HOWEVER...80 DEGREE MAX TEMPS STILL IN SIGHT ON SOME OF THE LOWER DESERTS DURING THE LATTER HALF OF THE WEEK. && .AVIATION... SOUTH-CENTRAL ARIZONA INCLUDING KPHX...KIWA AND KSDL... SHORT TERM: MOSTLY CLEAR SKIES WILL PREVAIL TONIGHT. SFC WINDS HAVE ALREADY TURNED E/SE AT KPHX (AND LIGHT AND VARIABLE ELSEWHERE) AND WILL MAINTAIN THESE HEADINGS THROUGH THE NIGHT WITH SPEEDS 3-5KT OR LESS. MONDAY MORNING: POTENTIAL STILL EXISTS FOR SOME FOG AROUND PHOENIX TERMINALS MONDAY MORNING...HOWEVER SHORT TERM HIGH RESOLUTION MODEL TRENDS SUGGEST FAR MORE LIMITED COVERAGE...AND DENSE FOG STAYING SOUTH OF THE METRO AREA. STILL MODERATE CONFIDENCE OF BRIEF PERIOD OF MVFR VSBY IN SE MARICOPA COUNTY (INCLUDING KPHX)...WITH FAR LESS CONFIDENCE OF LOWER CATEGORIES. MOST LIKELY TIMING WOULD BE IN THE 11Z-15Z TIME FRAME. OTHERWISE...EAST WINDS 3-6KT WILL PREVAIL INTO MONDAY AFTERNOON...THOUGH SOMEWHAT STRONGER WINDS UP TO 12KT WILL BE POSSIBLE IN A 1500-2000FT LAYER. SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA INCLUDING KIPL AND KBLH... NO AVIATION IMPACTS FOR SOUTHEAST CALIFORNIA WITH ONLY OCCASIONAL HIGH CIRRUS CLOUDS THROUGH MONDAY AFTERNOON. SFC WINDS WILL RETAIN A LIGHT NORTHERLY COMPONENT...THOUGH WILL BECOME VARIABLE AT TIMES AS THE UNDER A WEAK PRESSURE GRADIENT. AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS. && .FIRE WEATHER... TUESDAY THROUGH SATURDAY... WARMER TEMPERATURES ARE EXPECTED ACROSS THE REGION THIS WEEK ALONG WITH DRIER AIR. DESPITE THIS...AFTERNOON HUMIDITIES WILL ONLY DROP INTO THE 15-25 PERCENT RANGE EACH AFTERNOON WITH GOOD OVERNIGHT RECOVERIES EXPECTED. NO MAJOR WIND EVENTS ARE ANTICIPATED WITH WINDS FOLLOWING THE TYPICAL DIURNAL PATTERNS. && .PSR WATCHES/WARNINGS/ADVISORIES... AZ...NONE. CA...NONE. && $$ VISIT US ON FACEBOOK...TWITTER...AND AT WEATHER.GOV/PHOENIX DISCUSSION...AJ AVIATION...MO FIRE WEATHER...LEINS
AREA FORECAST DISCUSSION
NWS PUEBLO CO
533 AM MST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 533 AM MST MON FEB 2 2015 ...WAVES OF SNOW FOR THE CENTRAL MOUNTAINS...NICE REBOUND IN TEMPERATURES ELSEWHERE... NEXT SHORTWAVE/ASSOC UPPER JET IS MOVING ACROSS NRN CO EARLY THIS MORNING. HAVE SEEN SOME GUSTY WINDS REPORTED AT MTN TOP LEVEL AND ALONG THE LOWER EASTERN SLOPES OF THE SAWATCH RANGE...SANGRES...AND THE PIKES PEAK AND THE RAMPART RANGE. PEAK GUST SO FAR WAS 62 KTS AT 7BM...BUT WOULDN`T BE SURPRISED TO SEE A FEW STRONGER GUSTS ACROSS THE HIGHER PEAKS BEFORE MORNING. THESE STRONGER GUSTS SHOULD REMAIN FAIRLY LOCALIZED...AS 7BM HAS SINCE DROPPED BACK TO 45 KTS...BUT IT WILL REMAIN WINDY NONE-THE-LESS. HAVE BOOSTED WIND GUSTS IN MORNING GRIDS. CENTRAL MOUNTAINS WILL SEE SNOW CONTINUE THIS MORNING ASSOC WITH THIS WAVE EMBEDDED WITHIN OROGRAPHICALLY FAVORED NORTHWEST FLOW. HIGHER MTS COULD PICK UP AN INCH OR TWO THIS MORNING. MEANWHILE...LOW CLOUDS ACROSS EL PASO COUNTY WILL HANG IN EARLY THIS MORNING DUE TO WEAK SOUTHERLY UPSLOPE WINDS. STARTING TO SEE SOUTHWEST WINDS INCREASE ACROSS THE RAMPART RANGE THOUGH...AND LATEST HRRR SHOWS LOW LEVEL CLOUDS ERODING EAST OF KCOS AROUND 13Z. OTHERWISE...MID/HIGH LEVEL WAVE CLOUDINESS ALONG THE LEE OF THE SE MTS WILL SHIFT EASTWARD THIS MORNING WITH MOSTLY SUNNY SKIES EXPECTED BY AFTERNOON BEHIND THE DEPARTING UPPER WAVE. SNOW WILL ALSO DECREASE ACROSS THE CENTRAL MOUNTAINS AS DRIER AIR SPREADS IN BEHIND THE SYSTEM. MEANWHILE...LEE TROF SHOULD BRING REBOUNDING TEMPERATURES TO THE SOUTHEAST PLAINS...WITH HIGHS TODAY BACK INTO THE 50S. FAVORED AREAS ALONG THE LEE OF THE SE MTS WILL SEE SOME LOCAL GUSTS TO 25-30 MPH...MAINLY THIS MORNING. TONIGHT...LEE TROFFING SHOULD KEEP TEMPERATURES ON THE WARM SIDE...ESPECIALLY TO THE LEE OF THE SE MTS. NEXT WAVE MOVES IN LATE SPREADING ANOTHER ROUND OF SNOW INTO THE CENTRAL MOUNTAINS. ELSEWHERE WILL SEE SOME PASSING WAVE CLOUDINESS AT TIMES. WINDS WILL INCREASE AGAIN ACROSS THE HIGHER PEAKS TOWARDS DAWN TUESDAY. -KT .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 533 AM MST MON FEB 2 2015 RECENT LONGER TERM COMPUTER SIMULATIONS ARE CONTINUING TO REMAIN IN RELATIVELY CLOSE AGREEMENT PROJECTING GENERALLY DRY CONDITIONS(OUTSIDE OF THE CENTRAL MOUNTAINS AT TIMES) AND BASICALLY MILD TO WARM CONDITIONS(OUTSIDE OF WEDNESDAY) FROM TUESDAY INTO THE WEEKEND...THANKS TO A NORTHWESTERLY TO UPPER RIDGING PATTERN DEVELOPING OVER THE FORECAST DISTRICT. OVER PORTIONS OF THE CENTRAL MOUNTAINS...ACCUMULATING SNOW IN THE ONE TO FIVE INCH RANGE DURING ANY 12 HOUR PERIOD...IS ANTICIPATED FROM TUESDAY INTO WEDNESDAY NIGHT...ALTHOUGH RECENT 06Z/2ND COMPUTER SIMULATIONS HAVE STARTED TO TREND LOWER WITH POTENTIAL SNOW AMOUNTS. WFO PUEBLO WILL CONTINUE TO MONITOR REAL-TIME DATA AS WELL AS COMPUTER SIMULATIONS FOR LATER SNOW TRENDS AND POSSIBLE WINTER WEATHER HIGHLIGHTS. ELSEWHERE. AT THE SURFACE...THE SOUTHEASTERN COLORADO PLAINS LEE-SIDE TROUGHING FROM TUESDAY INTO TUESDAY NIGHT WILL BE REPLACED BY A COOLER AND SOMEWHAT MOIST NORTHEASTERLY TO EASTERLY SURFACE SURGE(DRIVEN BY A 1035 MB SURFACE HIGH LOCATED OVER EASTERN NEBRASKA AT 00Z THURSDAY) FROM WEDNESDAY MORNING INTO WEDNESDAY EVENING IN CONJUNCTION WITH A PASSING UPPER DISTURBANCE(GENERALLY FOCUSED TO THE NORTH AND EAST OF THE CWFA)...WHICH WILL ALLOW FOR THE COOL AND CLOUDY CONDITIONS...ESPECIALLY OVER EASTERN SECTIONS DURING THIS TIME-FRAME. IN ADDITION...SHOWERS WILL BE POSSIBLE...PRIMARILY OVER NORTHERN AND EASTERN SECTIONS OF THE FORECAST DISTRICT FROM WEDNESDAY INTO WEDNESDAY NIGHT. THEN THE COMBINATION OF VARYING DEGREES OF UPPER RIDGING AND EASTERN COLORADO SURFACE LEE-SIDE TROUGHING WILL ALLOW GENERALLY DRY AND ABOVE SEASONAL TEMPERATURE(ESPECIALLY EASTERN SECTIONS) FROM THURSDAY INTO THE WEEKEND. AT THIS TIME...IT APPEARS THAT THE WARMEST CONDITIONS OF THE LONGER TERM WILL BE NOTED FRIDAY AND SATURDAY WHILE COOLEST READING OCCUR WEDNESDAY. FINALLY...THE HIGHEST POTENTIAL FOR GUSTY WINDS ARE ANTICIPATED TUESDAY NIGHT AND THEN AGAIN THURSDAY NIGHT. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 533 AM MST MON FEB 2 2015 SOUTHERN EL PASO COUNTY WILL SEE MVFR/LOCAL IFR CONDITIONS THROUGH 13-14Z THIS MORNING DUE TO SOUTHERLY UPSLOPE WINDS BLOWING UP THE SOUTHERN SLOPES OF THE PALMER. AS THE DISTURBANCE MOVES ACROSS THE AREA...EXPECT LOW CLOUDS TO BREAK AS WINDS SHIFT FROM THE WEST TO NORTHWEST THIS MORNING. OTHERWISE...CONDITIONS WILL REMAIN VFR TODAY WITH PASSING MID AND HIGH CLOUDS THIS MORNING. LOWER ELEVATIONS WILL SEE WINDS UNDER 15 KTS...WHILE MTN TOP WINDS REMAIN QUITE STRONG THROUGH THE MORNING WITH GUSTS TO 50-60 KTS BEFORE WINDS DECREASE TO AROUND 30-40 KTS IN THE AFTERNOON. THE CENTRAL MTS WILL SEE IFR CONDITIONS THIS MORNING DUE TO -SN. VFR CONDITIONS WILL CONTINUE FOR THE TAF SITES INTO TONIGHT. THERE IS A LOW PROBABILITY FOR PATCHY FOG TO DEVELOP AT KALS LATE TONIGHT...BUT THREAT LOOKS VERY LOW AT THIS POINT. -KT && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$
EAST CENTRAL FLORIDA FORECAST DISCUSSION...CORRECTS ISSUANCE TIME
NWS MELBOURNE FL
910 AM EST MON FEB 2 2015 .DISCUSSION... A BROKEN BAND OF SHOWERS ACROSS THE GULF TO THE FL BIG BEND AND JACKSONVILLE IS MOVING EWD TOWARD THE AREA. A FEW LIGHTNING STRIKES WERE NOTED WELL OFFSHORE THE GULF COAST. WINDS HAVE INCREASED OVERNIGHT AND ARE WELL WITHIN THE BREEZY TO WINDY CATEGORY...POISED TO MIX TO THE SFC BY MID MORNING. MARGINAL SFC HEATING SHOULD ALLOW FOR SOME SB INSTABILITY BY AFTERNOON...ESP ACROSS THE S AREAS AND A SMALL THUNDER CHC REMAINS WARRANTED ALONG WITH THE INCREASING LIKELIHOOD OF SHOWERS FROM LATE MORNING THROUGH THE AFTERNOON ACROSS ALL ZONES. (PREVIOUS DISC) THE SOUTH HAS A BETTER CHANCE TO WARM UP BUT FRONTAL CONVERGENCE WILL BE WEAKENING WITH TIME. HAVE KEPT THE PREVIOUS FORECAST WHICH MENTIONS A SLIGHT CHANCE OF STORMS...BUT THE WEAK INSTABILITY AND INCREASED WIND PROFILES POINT MORE TO LOW TOPPED CONVECTION WITH SHOWERS CAPABLE OF PRODUCING STRONG/GUSTY WINDS. WILL GO WITH A LAKE WIND ADVISORY TODAY SINCE CANAVERAL PROFILERS AND FORECAST 925 MB WINDS POINT TO GUST CAPABILITY TO AROUND 30 MPH. COLD FRONT WILL PASS INTO SOUTH FLORIDA BY ABOUT 00Z SO WILL NOT CARRY ANY POPS THIS EVENING. EXPECT THE COOL/DRY AIR MASS TO PUSH MOST CLOUDINESS OUT OF THE AREA...BUT SOME STRATOCUMULUS MAY LINGER ALONG THE SOUTH COAST WHERE LOW LEVEL WINDS BECOME WEAKLY ONSHORE (NNE) LATE. MAV/MET GUIDANCE SHOWS TEMPERATURES FALLING INTO 40S FOR MOST OF THE AREA EXCEPT FOR LOWER 50S ALONG THE FAR SOUTH COAST. A FEW UPPER 30S ARE POSSIBLE IN THE FAR NORTH INTERIOR. && .AVIATION... SOUTHWEST/WEST WINDS WILL THEN BECOME GUSTY TO AROUND 25 KNOTS SHORTLY AT ALL SITES. PRE FRONTAL BAND OF CONVECTION HAS RECENTLY STARTED TO TAKE SHAPE IN THE GULF OF MEXICO. TIMING OF ACTIVITY AFFECTING NRN AND EVENTUALLY ALL SITES LOOKS ON TRACK. MOST OF THE VIS AND CIG OBSTRUCTIONS DURING PCPN ARE ANTICIPATED IN THE MVFR CATEGORY WITH BRIEF IFR CONDS PSBL IN HEAVIER SHOWERS. THE HRRR MODEL SHOWS THE BAND REACHING NORTHERN SITES AROUND 11 AM TO NOON AND MOVING QUICKLY THROUGH CENTRAL SECTIONS BY EARLY TO MID AFTERNOON AND SOUTHERN SITES LATE IN THE AFTERNOON. && .MARINE... HAZARDOUS CONDITIONS QUICKLY UNFOLDING NEAR AND OFFSHORE FOR SMALL CRAFT OPERATORS AND WILL PERSIST INTO TONIGHT. CHOPPY WIND DRIVEN SEAS WL OCCUR AND THE CURRENT HAZARDS LOOK GOOD LEADING UP THROUGH THE FRONTAL PASSAGE LATER TODAY. BY LATE TONIGHT THE WINDS WILL HAVE VEERED TO NORTHERLY AND DIMINISHED TO 15 KNOTS BUT SEAS WILL BE SLOW TO DIMINISH...ESPECIALLY IN THE GULF STREAM. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL VOLUSIA-INDIAN RIVER-INLAND VOLUSIA-MARTIN-NORTHERN BREVARD-NORTHERN LAKE-OKEECHOBEE-ORANGE- OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE-ST. LUCIE. AM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM EST THIS EVENING FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ JP/TES
EAST CENTRAL FLORIDA FORECAST DISCUSSION
NWS MELBOURNE FL
410 AM EST MON FEB 2 2015 .DISCUSSION... A BROKEN BAND OF SHOWERS ACROSS THE GULF TO THE FL BIG BEND AND JACKSONVILLE IS MOVING EWD TOWARD THE AREA. A FEW LIGHTNING STRIKES WERE NOTED WELL OFFSHORE THE GULF COAST. WINDS HAVE INCREASED OVERNIGHT AND ARE WELL WITHIN THE BREEZY TO WINDY CATEGORY...POISED TO MIX TO THE SFC BY MID MORNING. MARGINAL SFC HEATING SHOULD ALLOW FOR SOME SB INSTABILITY BY AFTERNOON...ESP ACROSS THE S AREAS AND A SMALL THUNDER CHC REMAINS WARRANTED ALONG WITH THE INCREASING LIKELIHOOD OF SHOWERS FROM LATE MORNING THROUGH THE AFTERNOON ACROSS ALL ZONES. (PREVIOUS DISC) THE SOUTH HAS A BETTER CHANCE TO WARM UP BUT FRONTAL CONVERGENCE WILL BE WEAKENING WITH TIME. HAVE KEPT THE PREVIOUS FORECAST WHICH MENTIONS A SLIGHT CHANCE OF STORMS...BUT THE WEAK INSTABILITY AND INCREASED WIND PROFILES POINT MORE TO LOW TOPPED CONVECTION WITH SHOWERS CAPABLE OF PRODUCING STRONG/GUSTY WINDS. WILL GO WITH A LAKE WIND ADVISORY TODAY SINCE CANAVERAL PROFILERS AND FORECAST 925 MB WINDS POINT TO GUST CAPABILITY TO AROUND 30 MPH. COLD FRONT WILL PASS INTO SOUTH FLORIDA BY ABOUT 00Z SO WILL NOT CARRY ANY POPS THIS EVENING. EXPECT THE COOL/DRY AIR MASS TO PUSH MOST CLOUDINESS OUT OF THE AREA...BUT SOME STRATOCUMULUS MAY LINGER ALONG THE SOUTH COAST WHERE LOW LEVEL WINDS BECOME WEAKLY ONSHORE (NNE) LATE. MAV/MET GUIDANCE SHOWS TEMPERATURES FALLING INTO 40S FOR MOST OF THE AREA EXCEPT FOR LOWER 50S ALONG THE FAR SOUTH COAST. A FEW UPPER 30S ARE POSSIBLE IN THE FAR NORTH INTERIOR. && .AVIATION... SOUTHWEST/WEST WINDS WILL THEN BECOME GUSTY TO AROUND 25 KNOTS SHORTLY AT ALL SITES. PRE FRONTAL BAND OF CONVECTION HAS RECENTLY STARTED TO TAKE SHAPE IN THE GULF OF MEXICO. TIMING OF ACTIVITY AFFECTING NRN AND EVENTUALLY ALL SITES LOOKS ON TRACK. MOST OF THE VIS AND CIG OBSTRUCTIONS DURING PCPN ARE ANTICIPATED IN THE MVFR CATEGORY WITH BRIEF IFR CONDS PSBL IN HEAVIER SHOWERS. THE HRRR MODEL SHOWS THE BAND REACHING NORTHERN SITES AROUND 11 AM TO NOON AND MOVING QUICKLY THROUGH CENTRAL SECTIONS BY EARLY TO MID AFTERNOON AND SOUTHERN SITES LATE IN THE AFTERNOON. && .MARINE... HAZARDOUS CONDITIONS QUICKLY UNFOLDING NEAR AND OFFSHORE FOR SMALL CRAFT OPERATORS AND WILL PERSIST INTO TONIGHT. CHOPPY WIND DRIVEN SEAS WL OCCUR AND THE CURRENT HAZARDS LOOK GOOD LEADING UP THROUGH THE FRONTAL PASSAGE LATER TODAY. BY LATE TONIGHT THE WINDS WILL HAVE VEERED TO NORTHERLY AND DIMINISHED TO 15 KNOTS BUT SEAS WILL BE SLOW TO DIMINISH...ESPECIALLY IN THE GULF STREAM. && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 6 PM EST THIS EVENING FOR COASTAL VOLUSIA-INDIAN RIVER-INLAND VOLUSIA-MARTIN-NORTHERN BREVARD-NORTHERN LAKE-OKEECHOBEE-ORANGE- OSCEOLA-SEMINOLE-SOUTHERN BREVARD-SOUTHERN LAKE-ST. LUCIE. AM...SMALL CRAFT ADVISORY FOR WINDS UNTIL 10 PM EST THIS EVENING FOR COASTAL WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE OUT 20 NM-COASTAL WATERS FROM SEBASTIAN INLET TO JUPITER INLET OUT 20 NM-COASTAL WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET OUT 20 NM. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM SEBASTIAN INLET TO JUPITER INLET 20 TO 60 NM OFFSHORE. SMALL CRAFT ADVISORY UNTIL 4 AM EST TUESDAY FOR WATERS FROM FLAGLER BEACH TO VOLUSIA BREVARD COUNTY LINE 20 TO 60 NM OFFSHORE-WATERS FROM VOLUSIA BREVARD COUNTY LINE TO SEBASTIAN INLET 20 TO 60 NM OFFSHORE. && $$ JP/TES
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1017 AM EST MON FEB 2 2015 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 254 AM EST MON FEB 2 2015 LIGHT SNOW BANDS ON THE BACK SIDE OF RETREATING LOW WILL PERSIST THIS MORNING ACROSS CENTRAL INDIANA...BUT HIGH PRESSURE WILL STRENGTHEN BY THIS AFTERNOON. AFTER CHILLY TEMPERATURES TODAY...THERE WILL BE A WARM UP BY TOMORROW. HOWEVER...A COLD FRONT PROGGED FOR TUESDAY NIGHT WILL BRING LIGHT SNOW SHOWERS THROUGH WEDNESDAY NIGHT. COLDER BUT DRY WEATHER CAN BE EXPECTED AT THE END OF THE WEEK AS HIGH PRESSURE RE-ESTABLISHES ITSELF OVER THE AREA. FURTHER OUT...THE NEXT SYSTEM IS SET TO MOVE THROUGH THE REGION NEXT WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1008 AM EST MON FEB 2 2015 RADAR MOSAIC AT 10 AM SHOWS SCATTERED FLURRIES AND A SMALL BAND OF LIGHT SNOW SHOWERS MOVING SOUTH SOUTHEAST THROUGH CENTRAL INDIANA. SHORT TERM MODELS ARE NOT DOING A GREAT JOB RESOLVING THESE PROBABLY DUE TO THEIR RELATIVELY LOCAL NATURE. THUS EVEN THOUGH HRRR AND RAP ARE NOT SHOWING MUCH OF ANYTHING GOING LATE THIS MORNING AND INTO THE AFTERNOON...BASED ON SATELLITE OBSERVATIONS...WIND DIRECTIONS AND TRENDS HAVE ADDED ISOLATED SNOW SHOWERS WITH SCATTERED FLURRIES INTO EARLY AFTERNOON FOR MOST OF THE AREA. ALSO KEPT POPS IN THE LATER AFTERNOON ALIGNED WITH POSSIBLE LAKE EFFECT BAND MIGRATING EASTWARD ACROSS THE NORTHERN COUNTIES. ALSO ADDED SOME FLURRIES ACROSS THE NORTHERN HALF OR SO OF THE AREA THROUGH THE AFTERNOON WITH THE NORTHERLY FLOW OFF THE LAKE AND CYCLONIC FLOW EXITING THE AREA. INCREASED CLOUD COVER INTO THE MID AFTERNOON ALSO BASED ON SATELLITE TRENDS AND ENHANCED LAKE EFFECT CLOUDS. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 254 AM EST MON FEB 2 2015 THE FOCUS OF THE SHORT TERM PERIOD IS A COLD FRONT PROGGED FOR TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. FIRST...STRONG SUBSIDENCE OVER CENTRAL INDIANA WILL RESULT IN DRY CONDITIONS FROM TONIGHT THROUGH TOMORROW. WEAK RADIATIONAL COOLING TONIGHT WILL ALLOW TEMPS TO DIP INTO THE SINGLE DIGITS AND TEENS...THUS RESULTING IN WIND CHILLS BELOW ZERO OVER THE NORTHERN HALF OF THE FORECAST AREA. FOCUS THEN TURNS TO THE IMPENDING COLD FRONT PASSAGE ON TUESDAY NIGHT. LIGHT SNOW SHOULD START SPREADING ACROSS THE AREA FROM NORTH TO SOUTH ON TUESDAY NIGHT. THE BEST DYNAMICS WITH FRONT WILL BE ON WEDNESDAY AND WEDNESDAY NIGHT. AS OF NOW...WILL GO WITH ALL SNOW FORECAST DUE TO THE COLD AIR ALOFT. HOWEVER...CONCERNED WITH TEMPERATURES TOPPING OFF IN THE LOW 40S ACROSS THE SOUTHERN COUNTIES ON WEDNESDAY...POSSIBLY CREATING MORE OF A RAIN/SNOW MIX DURING THE DAY. ANY LINGERING PRECIP ON WEDNESDAY NIGHT SHOULD DEFINITELY BE IN THE FORM OF SNOW THOUGH AS TEMPERATURES PLUMMET INTO THE SINGLE DIGITS AND TEENS BEHIND COLD FRONT. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 345 AM EST SUN FEB 2 2015 THE LONG TERM WILL START OUT DRY AND COLD AS ARCTIC HIGH PRESSURE OVER IOWA THURSDAY MORNING MOVES EAST ACROSS OUR REGION THURSDAY NIGHT. MODELS KEEP US UNDER A NORTHWEST FLOW ALOFT AS THIS HIGH PRESSURE MOVES ON TO THE SOUTHEAST FRIDAY AND SATURDAY. IT WILL BECOME DRY AND WARMER BY SATURDAY AS A SOUTHERLY FLOW DEVELOPS ACROSS OUR REGION. MODEL ENSEMBLES INDICATE AN UPPER TROUGH WILL DIG INTO OUR REGION OVER THE 2ND HALF OF THE WEEKEND. THERE IS ALSO A SURFACE LOW WHICH WILL TRACK ACROSS SOUTHERN INDIANA SUNDAY WHICH WILL RESULT IN CHANCES OF PRECIPITATION FOR SATURDAY NIGHT AND SUNDAY. THE 00Z EURO PULLS MORE COLD AIR INTO NORTH AND CENTRAL SECTIONS BY SUNDAY AND LOW LEVEL THICKNESS INDICATE PRECIPITATION SHOULD CHANGE OVER TO SNOW NORTH HALF BY SUNDAY. IN THE SOUTH...ANY PRECIPITATION SHOULD CONTINUE AS ALL RAIN. CONCERNING TEMPERATURES...WENT WITH A MOS BLEND THURSDAY THROUGH SATURDAY AND SHAVED A FEW DEGREES NORTH HALF SUNDAY BASED ON THE COLDER TREND OF THE EURO. && .AVIATION /DISCUSSION FOR THE 02/1200Z TAF ISSUANCE/... ISSUED AT 600 AM EST MON FEB 2 2015 SCATTERED LIGHT SNOW SHOWERS THIS MORNING WITH AREAS OF MVFR CEILINGS. THEN VFR REST OF THE PERIOD. STRONG LOW PRESSURE WAS OVER CENTRAL PENNSYLVANIA WHILE HIGH PRESSURE WAS BUILDING EAST FROM THE CENTRAL PLAINS. RADAR AND WEATHER DEPICTION INDICATED SCATTERED LIGHT SNOW SHOWERS WERE ACROSS THE REGION AND MAY CONTINUE TO MIDDAY IN SOME AREAS. OTHERWISE...THERE SHOULD BE A GRADUAL IMPROVEMENT OF FLIGHT CONDITIONS AS DRIER AIR SPREADS IN FROM THE WEST. CEILINGS SHOULD IMPROVE TO 3 THOUSAND FEET BY LATE MORNING AND THEN LOW CLOUDS WILL SCATTER OUT THIS AFTERNOON AND CLEAR LATE. MODEL SOUNDINGS INDICATE HIGH CLOUDS SHOULD MOVE IN BY EVENING WITH MID CLOUDS SPREAD IN LATE TONIGHT. A SHARP PRESSURE GRADIENT WILL PRODUCE NORTHWEST WINDS UP TO 15 KNOTS AND GUSTS UP TO 25 KNOTS THROUGH EARLY AFTERNOON. WINDS WILL DECREASE LATER THIS AFTERNOON AND BECOME WEST OR SOUTHWEST 5 TO 8 KNOTS TONIGHT AS PRESSURE GRADIENT SLACKENS. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD NEAR TERM...CP SHORT TERM...TDUD LONG TERM...JH AVIATION...JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON FACEBOOK...TWITTER AND YOUTUBE AT: WWW.FACEBOOK.COM/NWSINDIANAPOLIS WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS BALTIMORE MD/WASHINGTON DC
632 AM EST MON FEB 2 2015 .SYNOPSIS... LOW PRESSURE WILL MOVE ACROSS SOUTHERN PENNSYLVANIA THIS MORNING...DRAGGING A COLD FRONT ACROSS THE AREA. HIGH PRESSURE RETURNS ON TUESDAY. ANOTHER COLD FRONT MOVES THROUGH THE REGION WEDNESDAY NIGHT. HIGH PRESSURE BUILDS IN ONCE AGAIN LATE IN THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... HV BEEN ABLE TO TRIM WINTER WX ADVY SOME AS TEMPS SLOWLY WARM. EMPHASIS ON SLOW. MESONET TEMPS SUGGEST AOB 32F AIR STILL RESIDES ALONG MD/PA BORDER FM FREDERICK CO EWD. HV KEPT ADVY THERE...AND CANX THE REST. CWFA REMAINS IN A RELATIVE MIN WRT RADAR. SHWRS ASSOCD W/ CDFNT APPROACHING WRN ZNS ATTM. CDFNT IN WVA WL HEAD EWD AS LOW CROSSES SRN PA. ITS LOOKING A LTL SLOWER THAN PRVS CYCLES...WHICH WL KEEP A CHC OF PCPN INTO THE MRNG. HIEST POPS IN THE EAST INVOF ISENT LIFT AHD OF FNT. THE SLOWER TIMING WL ALSO PERMIT TEMPS TO RISE FURTHER DURING THE MRNG HRS. MAXT WL OCCUR PRIOR TO NOON. CFP WL STILL TAKE PLACE DURING THE AM. THE AFTN TEMP DROP WL BE MORE DRAMATIC W/ OF THE BLURDG...AND MAY BE TEMPERED BY COMPRESSIONAL WARMING TO THE EAST. AS CAA COMES CRASHING IN ON NW FLOW...MOMENTUM IN THE MIXED LYR WL INCREASE AS HGTS RISE RAPIDLY /AND LOW DEEPENS AS WELL...INCREASING P-GRAD/. MOST MDL SNDGS SUGGEST GUSTS AOA 40 KT. HV WIND ADVY IN PLACE...WHICH APPEARS PRUDENT. OF CONCERN ARE RAP SNDGS WHICH SUGGEST 50 KT AT 2000 FT. THIS WOULD BE THE TOP OF THE MIXED LYR. DONT XPCT FULL MIXING...BUT IT COULD TRIP MTN TOPS. HV HAD GNDC THIS WINTER OFFER HIGH WINDS BEFORE THEN PULL BACK...SO WONT UPGRADE HIER ELEVS /SUCH AS THE NEW SKYLINE DR ZONES/ TO HIGH WIND WARNING JUST YET...BUT IT IS AN ISSUE THAT WL BE FWDD ON TO DAY SHIFT TO WATCH CLOSELY. THE OTHER ISSUE THAT CAA/NW FLOW BRINGS IS UPSLP SHSN. TRAJ AND DEPTH UNDER INVSN BOTH LOOK GOOD...AND GDNC CRANKING OUT A DECENT PD OF SNOW MIDDAY...W/ INCRSG RATIOS. HV PUMPED UP TTLS...ENUF TO TRIGGER ADVYS IN EFFECT TIL 00Z. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... HIPRES BLDG EWD ACRS CWFA TNGT...AND WL BE THE PRIMARY WX INFLUENCE TUE. TNGT WL MARK THE END OF CAA...W/ THE ADVCTN SIGN REVERSING DURING THE MRNG TUE. BOTH PDS WL STILL BE COLD THO...W/ MINIMAL CHGS FM GOING FCST. ALTHO SKIES WL BE MOCLR TNGT...SUSPECT CONTD WINDS WL KEEP TEMPS FM DROPPING TOO FAR. AM ON THE COOLER SIDE OF MOS...BUT DIDNT UNDERCUT IT IN THE ABSENCE OF A GOOD RADL COOLING ENVIRONMENT. MAXT TUE WL BE STRUGGLING TO EXCEED 30F ACRS NRN MD/ERN WVA. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... LOW PRESSURE TRACKS ACROSS NEW ENGLAND TUESDAY NIGHT INTO WEDNESDAY. TRAILING COLD FRONT IS EXPECTED TO REMAIN WEST OF THE AREA...RESULTING IN A DRY FORECAST FOR THE CWA EXCEPT POSSIBLY A RAIN/SNOW MIX WEDNESDAY AFTERNOON OVER THE POTOMAC HIGHLANDS. TUESDAY NIGHT LOW TEMPS WILL BE IN THE 20S...FOLLOWED BY NEAR NORMAL HIGHS IN THE 40S ACROSS MOST OF THE FORECAST AREA WEDNESDAY. CHARLOTTESVILLE-FREDERICKSBURG CORRIDOR MIGHT REACH 50. MODELS ARE NOT YET IN GOOD AGREEMENT ABOUT TIMING OF THE COLD FROPA ACROSS THE CWA...WITH THE 00Z GFS BRINGING IT THROUGH WEDNESDAY NIGHT AND THE 00Z ECMWF HOLDING OFF UNTIL THURSDAY. MODELS ARE CONSISTENT THAT AVAILABLE MOISTURE WILL BE LIMITED. PTYPE WILL BE HIGHLY DEPENDENT ON TIMING OF THIS SYSTEM...SO CONFIDENCE IS LOW AT THIS POINT. LOW TEMPS WEDNESDAY NIGHT EXPECTED TO BE IN THE 20S AGAIN. COLD ADVECTION BEHIND THE FRONT THURSDAY KEEPS HIGH TEMPS BELOW FREEZING OVER MOST OF THE CWA...EXCEPT OVER SRN MD AND THE VA PIEDMONT WHERE HIGHS IN THE MID 30S ARE LIKELY. HIGH PRESSURE BUILDS IN AT THE END OF THE WORK WEEK WITH TEMPS AROUND 10-15 DEGREES BELOW NORMAL. LOW PRESSURE MAY IMPACT THE AREA AT SOME POINT OVER THE WEEKEND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... LLJ SLIDING E OF TERMINALS THIS MRNG. A LLWS RMK REMAINS IN DCA/BWI TAFS FOR A CPL MORE HRS. FLGT CONDS CONT TO BE MORE OPTIMISTIC THAN FCST. LIMITED AOB IFR TO BWI/MTN WHERE ITS ALREADY OBSVD. SINCE TAFS SENT...CHO DROPPED TO IFR. MAY NEED TO REASSESS. THERES STILL AN OPPORTUNITY FOR WORSENING CONDS PRIOR TO CFP...BUT THE WINDOW FOR THAT IS CLOSING. XPCT CFP 13Z MRB...14 OR 15Z ELSW. POST-FROPA...CLDS WL SCATTER OUT AND WNDS WL VEER NWLY/PICK UP SGFNTLY. SUSTAINED WNDS BHD FNT ARND 20 KT...W/ A FEW GUSTS REACHING 40-45 KT...SPCLY DURING THE AFTN. THIS WL IMPACT THE AFTN PUSH. SUNSET WL MARK THE BGNG OF THE END AS THE GRADIENT SUBSIDES. WNDS WONT BE NEALY AS MUCH OF AN ISSUE AFTER MIDNGT. HIPRES TUE WL MEAN VFR AND LGT WNDS...BACKING SWLY. VFR CONDITIONS EXPECTED TUESDAY NIGHT AND WEDNESDAY. S-SW WINDS WEDNESDAY...WITH SOME GUSTS TO AROUND 15KT POSSIBLE. PERIODS OF SUB-VFR POSSIBLE WEDNESDAY NIGHT AND/OR THURSDAY AS A COLD FRONT MOVES THROUGH. VFR EXPECTED LATE WEEK. NW WINDS GUSTING TO 20-25 KT POSSIBLE THURSDAY. && .MARINE... GNLY LGT WNDS ACRS THE WATERS THIS MRNG AS MIXING POOR. THERE IS A STRONG LLJ...MUCH OF WHICH ISNT MIXING DOWN. THE SERN SXN OF THE MARINE AREA PROVING TO BE THE EXCEPTION ATTM. AS A CDFNT NEARS...PCPN WL END...AND THE OPPORTUNITY FOR MIXING WL IMPRV A BIT. HV SCA IN PLACE TO ACCT FOR THIS. THE BIGGER CONCERN WL BE POST FROPA...WHEN WINDS WL VEER NWLY AND PICK UP SGFNTLY. A LTL WIGGLE ROOM IN EXACT TIMING...BUT THE PEAK PD WL INCL THE MID AND LT AFTN HRS...LASTING INTO ELY EVNG. GLW IN PLACE FOR THIS PD...WHEN MDL SNDGS SUGGEST GUSTS 40-45 KT. WL LKLY NEED SCA/S BYD THAT... BUT DONT WANT TO CONFUSE ISSUE W/ RAMPING UP AND RAMPING DOWN HAZARDS. TUE SHUD BE MUCH QUIETER TUE AS HIPRES BLDS. SCA CONDS MAY LINGER FOR A PORTION OF THAT TIME. SMALL CRAFT ADVISORY POSSIBLE WEDNESDAY UNDER S-SW FLOW AS PRESSURE GRADIENT INCREASES AHEAD OF AN APPROACHING COLD FRONT. SMALL CRAFT ADVISORY LIKELY BY THURSDAY AFTER THE COLD FRONT MOVES THROUGH...WITH POTENTIAL FOR GALES. WINDS DIMINISH FRIDAY AS HIGH PRESSURE BUILDS IN. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR DCZ001. MD...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MDZ501. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR MDZ003-004-501- 502. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR MDZ005-006-011-013-014-016>018-503>508. WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR MDZ004>006-507. VA...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR VAZ503. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR VAZ025>031-501- 503>505-507-508. WIND ADVISORY FROM NOON TODAY TO MIDNIGHT EST TONIGHT FOR VAZ036>040-050>057-502-506. WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ501- 503-505. WIND ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR WVZ050>053-055- 501>506. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EST TODAY FOR ANZ530>543. GALE WARNING FROM NOON TODAY TO 6 AM EST TUESDAY FOR ANZ530>543. && $$ SYNOPSIS...HTS/KCS NEAR TERM...HTS SHORT TERM...HTS LONG TERM...KCS AVIATION...HTS/KCS MARINE...HTS/KCS
AREA FORECAST DISCUSSION
NWS PITTSBURGH PA
555 AM EST MON FEB 2 2015 .SYNOPSIS... RAIN WILL CHANGEOVER TO SNOW THIS MORNING AS MUCH COLDER AIR MOVES IN BEHIND A DEPARTING LOW PRESSURE SYSTEM. DRY CONDITIONS THEN EXPECTED TONIGHT WITH LOW TEMPERATURES DROPPING DOWN TO THE SINGLE DIGITS. UNSETTLED WEATHER THEN EXPECTED WEDNESDAY AND THURSDAY AS ANOTHER FRONTAL SYSTEM IMPACTS THE REGION. && .NEAR TERM /THROUGH TONIGHT/... ENTERING THE LATTER STAGES OF A VERY COMPLEX SYSTEM WITH THE CENTER OF THE SFC LOW CURRENTLY NEARING THE DUBOIS AREA. WARM AIR HOLDS IN PLACE OVER NRN WV AND EXTREME SW PA...BUT WILL BE RETREATING QUICKLY AS MUCH COLDER AIR KNOCKS ON OUR WRN DOOR. BLENDED MOST RECENT RUN OF THE HRRR TEMPS IN WITH PREVIOUS TEMPS. FINALLY BEGINNING TO SEE TEMPS FALLS ASSOCIATED WITH THE TRAILING ARCTIC AIR ENTERING OUR REGION AS READINGS ACROSS CENTRAL OH ARE QUICKLY CRASHING BELOW FREEZING. WILL CONTINUE TO FOLLOW THIS ACROSS THE FORECAST AREA THIS MORNING AND HIGHLIGHT THE POTENTIAL FOR A FLASH FREEZE. MANY LOCATIONS ARE SEEING THE HIGH TEMPS CURRENTLY AND WILL FALL THROUGH THE DAY INTO THE SINGLE DIGITS OR TEENS. AS THE ARCTIC AIR ARRIVES LATER THIS MORNING...THE DENDRITIC GROWTH ZONE COMES CRASHING TO EARTH. THE RESULT WILL BE THE POTENTIAL FOR EFFICIENT SNOW SQUALLS AND SHOWERS AS FLOW VEERS TO NWRLY. EXPECTING A QUICK COATING OF SNOW FOR MOST LOCATIONS...UP TO AN INCH THROUGH ERN OH...1-2" ACROSS SW PA AND NRN WV. THE MNTS OF PA/MD/WV SHOULD SQUEEZE A LITTLE BIT MORE MOISTURE OUT WITH SNOW RATIOS JUMPING QUICKLY UP TO 20:1 OR BETTER. EXPECTING AN ADDITIONAL 2-4" SPECIFICALLY FOR GARRETT AND TUCKER COUNTIES. WITH THIS IN MIND...DECIDED TO EXTEND THE CURRENT WW.Y FOR THOSE TWO COUNTIES THROUGH 7PM TONIGHT. ELSEWHERE...ADVISORIES AND WARNINGS REMAIN UNTOUCHED. TAX && .SHORT TERM /TUESDAY/... A COLD DRY AND STABLE AIRMASS WILL SHIFT OVER THE AREA MON NIGHT WITH HIGH PRESSURE AT THE SFC AND NW FLOW ALOFT. CLOUDS WILL BREAK UP TUES MORNING...BUT SHOULD AVOID CLEARING COMPLETELY. THIS WILL SHOULD HELP KEEP TEMPS FROM COMPLETELY BOTTOMING OUT TUES MORNING...BUT BL DECOUPLING UNDER THE CALM HIGH WILL ENSURE A CRISP COLD MORNING. WAA KICKS IN TUES MORNING AS WINDS BACK TO THE SW. HIGH TEMPS TUES WILL BE WARMER THAN MONDAYS MARKS...BUT STILL NOWHERE NEAR AVG. TAX && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... UNSETTLED WEATHER IS EXPECTED THROUGHOUT THE SECOND HALF OF THE WEEK AS A CLIPPER SYSTEM QUICKLY BRUSHES PAST THE FORECAST AREA WEDNESDAY MORNING FOLLOWED BY AN UPPER TROUGH DIGGING SOUTH OVER THE MIDWEST AND IMPACTING THE REGION ON THURSDAY. MODELS ARE IN RELATIVELY GOOD AGREEMENT REGARDING SFC LOW PLACEMENT OF THE WEDNESDAY CLIPPER...KEEPING THE CENTER NORTH OF THE PA BORDER WHICH SHOULD KEEP SNOW ACCUMULATIONS RELATIVELY LOW ACROSS THE SOUTHERN HALF OF THE FORECAST AREA AND ONE TO THREE INCHES ALONG AND NORTH OF INTERSTATE 80. MODEL SOLUTIONS QUICKLY DIVERGE THEREAFTER IN HANDLING THE FOLLOWING UPPER TROUGH...WITH THE OPERATIONAL GFS BY FAR THE MOST PROGRESSIVE OUT OF ALL OF THE LATEST GUIDANCE WHILE OVERALL THE OTHER OPERATIONAL MODELS AND ENSEMBLES FAVOR A COLDER MORE AMPLIFIED SOLUTION. OPTED TO LEAN LARGELY ON LATEST EC AND GEFS WHICH ARE IN GOOD AGREEMENT WITH THEIR COLDER MORE AMPLIFIED SOLUTION. WITH THAT....EXPECT WEDNESDAY TO STILL BE RELATIVELY WARM BEFORE THE TRAILING COLD FRONT SWEEPS ACROSS THE REGION WEDNESDAY NIGHT AND SEND TEMPERATURES DROPPING DOWN TO SINGLE DIGITS ACROSS THE NORTH AND TEENS PITTSBURGH AND SOUTH. DO NOT ANTICIPATE MUCH RECOVERY ON THURSDAY WITH H850 TEMPS PROGGED TO BE BETWEEN TWO TO THREE STANDARD DEVIATIONS BELOW NORMAL LIGHT SNOW SHOWERS ACROSS THE REGION AS THE UPPER TROUGH PASSES OVER THE REGION. DRY CONDITIONS AND WARMER TEMPERATURES FRIDAY AND SATURDAY AS HEIGHTS RISE AND FLOW ALOFT TURNS WEST/SOUTHWEST AHEAD OF TH NEXT SYSTEM PROGGED TO IMPACT THE REGION NEXT SUNDAY. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... IFR CIG/VIS CONDITIONS TO PERSIST THROUGH THE FIRST HALF OF THE MORNING AS A COLD FRONT PASSES ACROSS THE REGION. RAIN/FREEZING WILL CHANGEOVER TO SNOW AND WINDS WILL SHIFT TO THE WEST/NORTHWEST WITH GUSTS UP TO 30KTS BEHIND THE FRONT. CONDITIONS WILL IMPROVE AS DRIER AIR MOVES IN...WITH MOST SITES EXPECTED TO IMPROVE TO MVFR BY EARLY AFTERNOON. OUTLOOK.../TUESDAY THROUGH SATURDAY/... NEXT CHANCE FOR WIDESPREAD RESTRICTIONS WILL BE WITH THE NEXT FRONTAL SYSTEM ON WEDNESDAY AND THURSDAY. && .PBZ WATCHES/WARNINGS/ADVISORIES... MD...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR MDZ001. OH...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR OHZ040-041. PA...WINTER STORM WARNING UNTIL NOON EST TODAY FOR PAZ007>009-015- 016. WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR PAZ013-014- 020>023-073-074. WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ041. && $$
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
635 AM EST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON FEB 2 2015 ...POTENTIAL FOR MODERATE TO POSSIBLY HEAVY LES OVER THE KEWEENAW LATE TODAY AND TONIGHT... WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A DRY NRLY FLOW PREVAILED ACROSS LAKE SUPERIOR AND UPPER MI BETWEEN A RIDGE OVER THE CENTRAL PLAINS AND A 996 MB LOW MOVING THROUGH THE OHIO VALLEY. RADAR LOOP SHOWS LINGERING LES OVER ERN MQT AND ALGER COUNTIES EARLY THIS MORNING WITH 900 MB TEMPS AROUND -21C PROVIDING ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...WITH INVERSION HEIGHTS DROPPING TO AROUND 3K FT AND THE DGZ NEAR LAKE SFC LES ACCUMULATION SHOULD BE LIMITED TO A RANGE FROM 1 TO POSSIBLY 3 INCHES THIS MORNING. TODAY...EXPECT LINGERING LES FOR NCNTRL ZONES TO BE PUSHED OFFSHORE AS FLOW BACKS IN RESPONSE TO A TROUGH DEVELOPING OVER NRN MN AND THE HIGH PRES SHIFTING INTO THE MID MISSISSIPPI VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. HOWEVER...LATE IN THE DAY LOW-LVL CONVERGENCE WILL INCREASE OVER THE TIP OF KEWEENAW PENINSULA AS A SHORTWAVE DISTURBANCE AND THE ASSOC SFC TROUGH OVER NRN MN DROPS ACROSS NCNTRL AND ERN LAKE SUPERIOR. THIS ENHANCED CONVERGENCE COMBINED WITH WEAK LIFT AND MOISTURE DEEPENING TO 10 KFT SHOULD LEAD TO DOMINANT LES BAND FORMING OVER THE TIP OF THE KEWEENAW LATE TODAY WITH A POTENTIAL FOR MODERATE TO POSSIBLY HEAVY SNOW. TONIGHT...AS SFC TROF BEGINS TO SAG SE ACROSS THE CWA...MODERATE TO POSSIBLY HEAVY DOMINANT LES BAND WILL GET PUSHED SOUTH ACROSS THE KEWEENAW PENINSULA. WITH H85 TEMPS NEAR -20C...STEEPENING 1000-850MB LAPSE RATES AND ENHANCED LIFT/OMEGA THROUGH THE DGZ...EXPECT THE POTENTIAL FOR SNOWFALL RATES IN EXCESS OF 1" PER HOUR AS LES BAND SAGS SOUTH ACROSS THE KEWEENAW. DOES APPEAR THAT THE HEAVIEST SNOW WILL NOT LAST MORE THAN A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL. GIVEN ABOVE FAVORABLE FACTORS FELT THAT LES ADVISORY WAS WARRANTED FOR OVER THE KEWEENAW LATE TODAY THROUGH TONIGHT. EXPECT SNOW TO BEGIN TO TAPER OFF AND BECOME MORE MULTIBAND AS DEEPER MOISTURE DEPARTS IN THE WAKE OF THE EXITING TROUGH. LOOK FOR 3-6 INCH SNOWFALL ACCUMULATION OVER KEWEENAW COUNTY WITH 3-5 INCHES OVER NORTHERN HOUGHTON COUNTY. ELSEWHERE THAN SCT LES OVER THE FAR WEST...EXPECT LITTLE IF ANY SNOW ELSEWHERE AS WESTERLY FLOW SHOULD KEEP REST OF LES OUT OVER LAKE SUPERIOR. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 358 AM EST MON FEB 2 2015 GENERALLY LIGHT WNW WIND LES TUE INTO EARLY TUE NIGHT WITH 850MB TEMPS AROUND -20C. EXPECT 1-3 INCHES OF SNOW IN THE WNW WIND SNOWBELTS FROM 12Z TUE TO 06Z WED. ATTENTION IN THE LONG TERM IS LARGELY WITH LES AND ASSOCIATED HAZARDS LATE TUE NIGHT THROUGH WED NIGHT ALONG AND BEHIND A SHORTWAVE/COLD FRONT. THE SHORTWAVE ENERGY IS SHOWN BY MAJORITY OF MODELS TO STAY S OF THE CWA...ALTHOUGH THE NAM DOES BRING ENERGY AND RESULTING LIGHT QPF AMOUNTS OVER MOST OF UPPER MI TUE NIGHT. THE SFC TROUGH/COLD FRONT LOOKS TO MOVE THROUGH THE CWA LATE TUE NIGHT INTO WED MORNING. THE TRAILING 850MB THERMAL TROUGH AXIS WILL PASS THROUGH THE AREA WED AFTERNOON AND EVENING...BRINGING 850MB TEMPS AS LOW AS -28C IN THE NW FLOW. MODEL SOUNDINGS SUGGEST THAT LAKE INDUCED EQUILIBRIUM LEVELS WILL RISE ABOVE 11KFT UNDER THE THERMAL TROUGH AXIS...POINTING TO MODERATE TO HEAVY LES IN THE NW WIND SNOWBELTS. DENDRITE SIZE SHOULD BE PRETTY SMALL DUE TO THE EXTENT OF THE COLD AIRMASS PUTTING MOST OF THE CONVECTIVE LAYER COLDER THAN -20C. WHILE THE SMALL FLAKES WILL LIMIT ACCUMULATIONS SOMEWHAT...THE THREAT OF LOW VIS AND BLOWING/DRIFTING SNOW WILL BE MORE SUBSTANTIAL. DO EXPECT LOCALLY VERY POOR CONDITIONS ALONG LAKE SUPERIOR AS THE FRONT PASSES LATE TUE NIGHT OR EARLY WED MORNING AS WELL. THE LES WILL WEAKEN WED NIGHT AS A SFC RIDGE MOVES INTO WRN LAKE SUPERIOR. WILL KEEP QPF AMOUNTS SIMILAR TO PREVIOUS FORECAST WITH 0.30-0.35 INCHES IN THE NW WINDS SNOWBELTS...WHICH LEADS TO SNOWFALL AMOUNTS GREATER THAN 6 INCHES IN THOSE LOCATIONS. WILL CONTINUE TO MENTION EVENT IN HWO THOUGH A HEADLINE WILL PROBABLY BE NEEDED AT SOME POINT. WARMER TEMPS AND SW FLOW BEHIND THE SFC RIDGE AND AHEAD OF A SFC TROUGH WILL KEEP SNOW OUT OF THE LAND FORECASTS FOR MUCH OF THU AND THU NIGHT. THERE IS STILL QUITE OF A BIT OF UNCERTAINTY FOR FRI INTO THE WEEKEND AS DETAILS WITH A COUPLE OF CLIPPER SYSTEMS REMAIN UNCERTAIN ON FRI INTO FRI NIGHT AND SAT INTO SUN. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 625 AM EST MON FEB 2 2015 EXPECT MVFR CLOUDS TO LIFT BY LATE MORNING AT BOTH KIWD AND KSAW AS WINDS BACK TO THE WEST-SOUTHWEST. INCREASING MOISTURE LATE TONIGHT WITH THE ARRIVAL OF A SFC TROUGH FM NW OF LAKE WILL ALLOW FOR MVFR CONDITIONS TO RETURN AT BOTH KIWD AND KSAW WITH SOME LIGHT LES EXPECTED AT KIWD. AT KCMX...MVFR CIGS SHOULD PERSIST THROUGH THE FCST PD. HOWEVER...LATE THIS EVENING INTO THE OVERNIGHT HOURS...EXPECT IFR VSBYS IN SNOW AS A DOMINANT LES BAND SLOWLY SAGS SOUTH ACROSS THE KEWEENAW PENINSULA. VSBYS WILL IMPROVE TO MVFR LATE TONIGHT AS WINDS SHIFT MORE NW AND THE DOMINANT LES BAND SAGS SOUTH OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON FEB 2 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH TODAY... THEN TURN TO THE NORTHWEST BEHIND THE TROUGH LATE TONIGHT AND TUESDAY. WEST WIND GUSTS OVER THE ERN HALF OF LAKE MAY BRIEFLY APPROACH GALE FORCE THIS EVENING...OTHER EXPECT WINDS AT OR BLO 30 KTS. HEAVY FREEZING SPRAY IS EXPECTED OVER PORTIONS OF THE WRN LAKE THIS AFTERNOON INTO THIS EVENING AND ERN LK SUPERIOR TONIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES ON WEDNESDAY. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON LATE FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING FROM 6 PM THIS EVENING TO 6 AM EST TUESDAY FOR LSZ266-267. HEAVY FREEZING SPRAY WARNING FROM 4 PM THIS AFTERNOON TO 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...VOSS MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
525 AM EST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON FEB 2 2015 ...POTENTIAL FOR MODERATE TO POSSIBLY HEAVY LES OVER THE KEWEENAW LATE TODAY AND TONIGHT... WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A DRY NRLY FLOW PREVAILED ACROSS LAKE SUPERIOR AND UPPER MI BETWEEN A RIDGE OVER THE CENTRAL PLAINS AND A 996 MB LOW MOVING THROUGH THE OHIO VALLEY. RADAR LOOP SHOWS LINGERING LES OVER ERN MQT AND ALGER COUNTIES EARLY THIS MORNING WITH 900 MB TEMPS AROUND -21C PROVIDING ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...WITH INVERSION HEIGHTS DROPPING TO AROUND 3K FT AND THE DGZ NEAR LAKE SFC LES ACCUMULATION SHOULD BE LIMITED TO A RANGE FROM 1 TO POSSIBLY 3 INCHES THIS MORNING. TODAY...EXPECT LINGERING LES FOR NCNTRL ZONES TO BE PUSHED OFFSHORE AS FLOW BACKS IN RESPONSE TO A TROUGH DEVELOPING OVER NRN MN AND THE HIGH PRES SHIFTING INTO THE MID MISSISSIPPI VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. HOWEVER...LATE IN THE DAY LOW-LVL CONVERGENCE WILL INCREASE OVER THE TIP OF KEWEENAW PENINSULA AS A SHORTWAVE DISTURBANCE AND THE ASSOC SFC TROUGH OVER NRN MN DROPS ACROSS NCNTRL AND ERN LAKE SUPERIOR. THIS ENHANCED CONVERGENCE COMBINED WITH WEAK LIFT AND MOISTURE DEEPENING TO 10 KFT SHOULD LEAD TO DOMINANT LES BAND FORMING OVER THE TIP OF THE KEWEENAW LATE TODAY WITH A POTENTIAL FOR MODERATE TO POSSIBLY HEAVY SNOW. TONIGHT...AS SFC TROF BEGINS TO SAG SE ACROSS THE CWA...MODERATE TO POSSIBLY HEAVY DOMINANT LES BAND WILL GET PUSHED SOUTH ACROSS THE KEWEENAW PENINSULA. WITH H85 TEMPS NEAR -20C...STEEPENING 1000-850MB LAPSE RATES AND ENHANCED LIFT/OMEGA THROUGH THE DGZ...EXPECT THE POTENTIAL FOR SNOWFALL RATES IN EXCESS OF 1" PER HOUR AS LES BAND SAGS SOUTH ACROSS THE KEWEENAW. DOES APPEAR THAT THE HEAVIEST SNOW WILL NOT LAST MORE THAN A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL. GIVEN ABOVE FAVORABLE FACTORS FELT THAT LES ADVISORY WAS WARRANTED FOR OVER THE KEWEENAW LATE TODAY THROUGH TONIGHT. EXPECT SNOW TO BEGIN TO TAPER OFF AND BECOME MORE MULTIBAND AS DEEPER MOISTURE DEPARTS IN THE WAKE OF THE EXITING TROUGH. LOOK FOR 3-6 INCH SNOWFALL ACCUMULATION OVER KEWEENAW COUNTY WITH 3-5 INCHES OVER NORTHERN HOUGHTON COUNTY. ELSEWHERE THAN SCT LES OVER THE FAR WEST...EXPECT LITTLE IF ANY SNOW ELSEWHERE AS WESTERLY FLOW SHOULD KEEP REST OF LES OUT OVER LAKE SUPERIOR. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 358 AM EST MON FEB 2 2015 GENERALLY LIGHT WNW WIND LES TUE INTO EARLY TUE NIGHT WITH 850MB TEMPS AROUND -20C. EXPECT 1-3 INCHES OF SNOW IN THE WNW WIND SNOWBELTS FROM 12Z TUE TO 06Z WED. ATTENTION IN THE LONG TERM IS LARGELY WITH LES AND ASSOCIATED HAZARDS LATE TUE NIGHT THROUGH WED NIGHT ALONG AND BEHIND A SHORTWAVE/COLD FRONT. THE SHORTWAVE ENERGY IS SHOWN BY MAJORITY OF MODELS TO STAY S OF THE CWA...ALTHOUGH THE NAM DOES BRING ENERGY AND RESULTING LIGHT QPF AMOUNTS OVER MOST OF UPPER MI TUE NIGHT. THE SFC TROUGH/COLD FRONT LOOKS TO MOVE THROUGH THE CWA LATE TUE NIGHT INTO WED MORNING. THE TRAILING 850MB THERMAL TROUGH AXIS WILL PASS THROUGH THE AREA WED AFTERNOON AND EVENING...BRINGING 850MB TEMPS AS LOW AS -28C IN THE NW FLOW. MODEL SOUNDINGS SUGGEST THAT LAKE INDUCED EQUILIBRIUM LEVELS WILL RISE ABOVE 11KFT UNDER THE THERMAL TROUGH AXIS...POINTING TO MODERATE TO HEAVY LES IN THE NW WIND SNOWBELTS. DENDRITE SIZE SHOULD BE PRETTY SMALL DUE TO THE EXTENT OF THE COLD AIRMASS PUTTING MOST OF THE CONVECTIVE LAYER COLDER THAN -20C. WHILE THE SMALL FLAKES WILL LIMIT ACCUMULATIONS SOMEWHAT...THE THREAT OF LOW VIS AND BLOWING/DRIFTING SNOW WILL BE MORE SUBSTANTIAL. DO EXPECT LOCALLY VERY POOR CONDITIONS ALONG LAKE SUPERIOR AS THE FRONT PASSES LATE TUE NIGHT OR EARLY WED MORNING AS WELL. THE LES WILL WEAKEN WED NIGHT AS A SFC RIDGE MOVES INTO WRN LAKE SUPERIOR. WILL KEEP QPF AMOUNTS SIMILAR TO PREVIOUS FORECAST WITH 0.30-0.35 INCHES IN THE NW WINDS SNOWBELTS...WHICH LEADS TO SNOWFALL AMOUNTS GREATER THAN 6 INCHES IN THOSE LOCATIONS. WILL CONTINUE TO MENTION EVENT IN HWO THOUGH A HEADLINE WILL PROBABLY BE NEEDED AT SOME POINT. WARMER TEMPS AND SW FLOW BEHIND THE SFC RIDGE AND AHEAD OF A SFC TROUGH WILL KEEP SNOW OUT OF THE LAND FORECASTS FOR MUCH OF THU AND THU NIGHT. THERE IS STILL QUITE OF A BIT OF UNCERTAINTY FOR FRI INTO THE WEEKEND AS DETAILS WITH A COUPLE OF CLIPPER SYSTEMS REMAIN UNCERTAIN ON FRI INTO FRI NIGHT AND SAT INTO SUN. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z MONDAY NIGHT) ISSUED AT 1201 AM EST MON FEB 2 2015 MVFR CONDITIONS WITH LIGHT SNOW SHOWERS WILL CONTINUE AT SAW AND CMX OVERNIGHT IN A N FLOW. IWD WILL SEE MVFR CONDITIONS TONIGHT IN THE SNOW SHOWERS. IWD AND SAW WILL BACK WINDS TO THE SOUTHWEST AND PUSH THE LAKE EFFECT CLOUDS NORTH OF THE AREA AND SHOULD GO VFR MON MORNING WHILE CMX STAYS IN THE LAKE EFFECT MVFR CATEGORY CLOUDS THROUGH THE PERIOD. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON FEB 2 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH TODAY... THEN TURN TO THE NORTHWEST BEHIND THE TROUGH LATE TONIGHT AND TUESDAY. WEST WIND GUSTS OVER THE ERN HALF OF LAKE MAY BRIEFLY APPROACH GALE FORCE THIS EVENING...OTHER EXPECT WINDS AT OR BLO 30 KTS. HEAVY FREEZING SPRAY IS EXPECTED OVER PORTIONS OF THE WRN LAKE THIS AFTERNOON INTO THIS EVENING AND ERN LK SUPERIOR TONIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES ON WEDNESDAY. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON LATE FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY FROM 6 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING FROM 6 PM THIS EVENING TO 6 AM EST TUESDAY FOR LSZ266-267. HEAVY FREEZING SPRAY WARNING FROM 4 PM THIS AFTERNOON TO 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...TITUS AVIATION...07 MARINE...VOSS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1040 AM EST MON FEB 2 2015 .SYNOPSIS... AFTER THE WINTER STORM EXITS THE REGION TODAY, BITTERLY COLD AIR WILL MOVE INTO NY AND PA FOR TONIGHT. A WEAKER STORM WILL BRING LIGHT SNOW TO THE REGION LATE WEDNESDAY, FOLLOWED BY EVEN COLDER AIR FOR THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 1040 AM UPDATE... WE HAVE DROPPED THE SOUTHWESTERN CORNER OF THE WARNING. RADAR SHOWS THAT THE STEADY PRECIPITATION HAS MOVED OUT OF THIS REGION, AND HRRR SUGGESTS THAT THE DEFORMATION ZONE ACTIVITY OVER WESTERN NY WILL LIFT ACROSS THE FINGER LAKES AND FIZZLE OUT THIS AFTERNOON. WE MAY DROP ANOTHER BLOCK OF COUNTIES IN THE NEXT 1-2 HOURS. HOWEVER, WE WILL ALLOW THE MODERATE BANDS MOVING THROUGH PORTIONS OF NORTHERN PA AND THE LOWER SUSQUEHANNA REGION TO CLEAR THE AREA FIRST. 430 AM UPDATE... AT 430 AM SFC LOW PRES WAS LOCATED OVER WESTERN PA. LOCAL RADARS/OBS SHOW LIGHT TO MODERATE SNOW ACROSS THE REGION WITH ANOTHER AREA OF STRONG RETURNS HEADING TOWARD THE REGION FROM WRN PA. THE HEAVIEST SNOWFALL RATES WILL CONTINUE THROUGH MID MORNING THEN THE ACTIVITY WILL GRADUALLY WEAKEN AS JET DYNAMICS AND ISENTROPIC LIFT MOVES EAST OF FA. THE SFC LOW WILL TRACK EAST ACROSS NORTH CENTRAL PA THEN OFF THE NJ COAST BY MIDDAY. A BRIEF PERIOD FGEN FORCING IN THE WESTERN CATSKILLS MAY KEEP OCCASIONAL HEAVY SNOW HERE THROUGH EARLY AFTERNOON. MODEL CONSENSUS CONTINUES TO INDICATE THE SNOW WILL MIX WITH SLEET/FZRA BRIEFLY THIS MORNING ACROSS PARTS OF NE PA. OBS IN THE STATE COLLEGE AREA ARE ALREADY INDICATING THIS TYPE OF PRECIP. THE ACTIVITY WILL CHANGE BACK TO SNOW BY MID/LATE MORNING. TOTAL SNOW ACCUMS IN GENERAL WILL RANGE FROM 8 TO 12 INCHES ACROSS CENTRAL NY AND NRN TIER OF PA AND 5 TO 8 IN THE FAR SE WITH SOME LIGHT ICING. ONCE THE SYSTEM LIFTS NORTHEAST INTO COASTAL NEW ENGLAND THIS AFTERNOON STRONG NW WINDS WILL CAUSE BLOWING AND DRIFTING SNOW ALONG WITH FALLING TEMPS. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY NIGHT/... TONIGHT...VERY COLD AIRMASS WILL BE USHERED BACK INTO THE REGION THIS EVENING UNDER NW FLOW. PARTS OF THE ERN CWA MAY REQUIRE A WIND CHILL ADVISORY OVERNIGHT BUT WILL LET NEXT SHIFT CONSIDER THIS FLAG. NW FLOW WILL GRADUALLY BACK OVERNIGHT BRINGING SCATTERED LAKE EFFECT SNOW SHOWERS FROM THE FINGER LAKES REGION NORTH ACROSS THE SYR AREA INTO THE SOUTHERN TUG HILL BY DAYBREAK. LOW INVERSION, SFC RIDGING AND VERY DRY AIRMASS WILL RESULT IN ONLY MINOR ACCUMS. REST OF AREA WILL BE DRY UNDER PARTLY CLOUDY SKIES WITH MIN TEMPS GENERALLY ZERO TO 10 BELOW. TUESDAY...SFC HIGH PRES IN THE MID ATLANTIC AND A SFC TROF DROPPING INTO THE UPPER GREAT LAKES WILL PRODUCE A SOUTHWEST FLOW. A PRECIP FREE DAY IS EXPECTED ALONG WITH PARTLY SUNNY TO MOSTLY CLOUDY SKIES. MAX TEMPS WILL GENERALLY BE IN THE TEENS WITH THE NORMALLY WARMER AREAS IN THE FINGER LAKES AND CENTRAL SRN TIER APPROACHING 20. TUESDAY NIGHT/WEDNESDAY...A WEAK CLIPPER TYPE SYSTEM WILL TRACK FROM THE MID WEST ACROSS LOWER MICHIGAN TO SOUTHERN QUEBEC BY WED EVENING. THIS FEATURE WILL BEING SOME LIGHT SNOW MAINLY TO CENTRAL NY PRIMARILY LATE TUE NIGHT THROUGH WED. WILL CONTINUE TO ADVERTISE LIKELY POPS OVER THE NRN CWA AND CHC ELSEWHERE. SNOW ACCUMS OF 1 TO 3 INCHES ARE POSSIBLE. ON WED TEMPS WILL MODERATE TO AROUND THE FREEZING MARK AHEAD OF THE APPROACHING SFC TROF. WEDNESDAY NIGHT...AS THIS SFC LOW CONTINUES LIFTING OFF TO THE NE THE TRAILING COLD FRONT WILL DROP THROUGH THE REGION BRINGING THE POTENTIAL FOR MORE SNOW SHOWERS. BEHIND THIS BOUNDARY ANOTHER PUSH OF ARCTIC AIR WILL MOVE THROUGH THE NORTHEAST. && .LONG TERM /THURSDAY THROUGH SUNDAY/... 2 AM UPDATE... LITTLE CHANGE. POPULATED WITH CURRENT WPC GUIDANCE. WEAK SYSTEM CENTERED SOUTH OF REGION WILL BRING LIGHT SNOW. LITTLE TO ADD TO PREVIOUS DISCUSSION. PREVIOUS DISCUSSION FROM SUNDAY AFTERNOON... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... 1230 AM UPDATE... WIDESPREAD IFR VSBYS ACROSS THE TERMINALS. VSBYS UNDER 1SM BY 8Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS NOW, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MIDDAY. THE SNOW TAPERS OFF BUT GUSTY WINDS COULD CAUSE BLOWING SNOW KEEPING VSBYS IFR AT TIMES. ALSO DURING THE AFTN THE LOW LEVEL FLOW GOES TO NW STARTING THE LAKE EFFECT AND ALSO WRAP AROUND. NY TERMINALS 2 TO 3 MILES. CIGS MOSTLY 1 TO 2K FT WILL DROP SOME THROUGH 14Z THEN SLOWLY IMPROVE. EXCEPTION MAY BE ITH AND BGM IN THE AFTN WITH THE LES. EAST WINDS 5 T0 10 KTS THIS MORNING. WINDS SHIFTING TO THE NORTHWEST 16 TO 19Z AT 10 KTS INCREASING TO 10 TO 15 WITH GUSTS TO 20-25 KTS. SLOWLY DIMINISHING AFTER 00Z. OUTLOOK... TONIGHT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR PAZ039- 040-043-044-047-048-072. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 016>018-036-037-044>046-056-057-062. && $$ SYNOPSIS...DJP NEAR TERM...DJP/RRM SHORT TERM...RRM LONG TERM...DJP/TAC AVIATION...TAC
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
1002 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE THIS AFTERNOON. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY AND MOVE OFFSHORE TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS THE AREA WEDNESDAY NIGHT. LOW PRESSURE WILL DEVELOP ON THE FRONT OFFSHORE OF THE COAST THURSDAY AND MOVE AWAY THE REGION FRIDAY. HIGH PRESSURE WILL RE-BUILD OVER THE REGION NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 930 AM MONDAY...FORECAST UPDATED TO RAISE TEMPS/DEWPOINTS A FEW DEGREES IN MANY AREAS...PLUS INCREASE POPS TO CATEGORICAL EVERYWHERE THROUGH MIDDAY AS RAIN OVERSPREADS THE ENTIRE FA. AS OF 650 AM MONDAY...WIDESPREAD RAIN CONTINUES OVER THE REGION...ESPECIALLY THE COASTAL PLAINS AS RAIN COVERAGE HAS DIMINISHED A BIT AT THE COAST. LATEST 3KM HRRR SHOWS THE RAIN FILLING BACK IN THROUGH LATE MORNING AND HAVE CONTINUED LIKELY TO CATEGORICAL POPS INTO EARLY AFTERNOON. COLD FRONT CURRENTLY WORKING THROUGH THE TENNESSEE VALLEY SHOULD ARRIVE AROUND MIDDAY AND MOVE OFFSHORE BY EARLY AFTERNOON...ENDING THE BULK OF THE PRECIPITATION AS THE UPPER LEVELS GRADUALLY DRY THROUGH 00Z OR SO. HAVE LIKELY TO CATEGORICAL POPS THROUGH ABOUT NOON...THEN GRADUALLY TAPERING EAST TO WEST WITH ALL THREAT OF PRECIPITATION ENDED BY 00Z AND SKIES CLEARING RAPIDLY AS DEEP DRY AIR MIXES TO THE SURFACE. GUSTY WINDS BOTH AHEAD AND BEHIND THE COLD FRONT MAY GUST TO 35 MPH ON THE OUTER BANKS AND WILL ISSUE A WIND ADVISORY FROM 17Z TO 00Z FOR THAT AREA. DESPITE CLOUDS...WARM ADVECTION HAS ALLOWED TEMPS TO RISE OVERNIGHT AND TEMPS WILL CONTINUE TO RISE TO AROUND 60 OVER A GOOD PORTION OF THE AREA TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... AS OF 4 PM MONDAY...HIGH PRESSURE WILL BUILD IN BEHIND THE COLD FRONT TONIGHT WITH TEMPERATURES DROPPING INTO THE MID/UPPER 20S OVER MOST LAND AREAS TO RIGHT AROUND FREEZING ON THE OUTER BANKS. WINDS SHOULD SUBSIDE TOWARD MORNING...BUT THE REMAINING BREEZE WILL PUSH APPARENT TEMPERATURE VALUES INTO THE TEENS EARLY TUESDAY MORNING UNDER GENERALLY CLEAR SKIES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 3 AM MON...THE EXTENDED PERIOD BEGINS DRY AS A SURFACE RIDGE PASSES THROUGH THE REGION TUESDAY AND MOVES OFF THE COAST WEDNESDAY. AN UPPER LEVEL DISTURBANCE OVER THE NORTHERN PLAINS WILL MOVE SOUTHEAST WEDNESDAY NIGHT AND THURSDAY WILL COMBINE WITH A SOUTHERN STREAM DISTURBANCE MOVING ACROSS THE NORTHERN GULF TO INDUCE LOW PRESSURE IN THE GULF OF MEXICO. THE LOW WILL PASS BY THE SOUTHEAST COAST AT THAT TIME BUT FORECAST TEMPS AND THICKNESSES INDICATE PRECIP WILL BE ALL RAIN. THE SYSTEM QUICKLY MOVES OFF TO THE NORTHEAST THURSDAY NIGHT WITH SURFACE HIGH PRESSURE BUILDING IN FOR FRIDAY AND SATURDAY. THE HIGH SHIFTS OFF THE COAST ON SUNDAY WITH THE NEXT SYSTEM ARRIVING ON MONDAY WITH A CHANCE OF RAIN. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... SHORT TERM /THROUGH 12Z TUESDAY/... AS OF 655 AM MONDAY...LIGHT TO OCCASIONALLY MODERATE RAIN CONTINUES ACROSS EASTERN NC WITH MVFR CEILINGS AT KPGV. HOWEVER...VFR CONDITIONS REPORTED AT ALL OTHER TAF SITES. OTHER THAN PERHAPS A BRIEF PERIOD OF MVFR IN HEAVIER SHOWERS...EXPECT CONDITIONS TO REMAIN IN THE VFR RANGE THROUGH THE PERIOD. UPPER DRYING COMMENCES AROUND 18Z THROUGH THE EVENING AS SKIES CLEAR BY LATE EVENING. GUSTY SW WINDS WILL CONTINUE INTO AFTERNOON WITH WIND GUSTS 20-30KT...THIS COULD RESULT IN CROSSWIND IMPACTS AT EWN. THE COLD FRONT WILL MOVE THROUGH THE TERMINALS MONDAY AFTERNOON...WITH GUSTY WINDS BECOMING W/NW. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...VFR/SKC TUE THROUGH WED WITH WINDS LESS THAN 10 KNOTS...FROM THE NORTHWEST TUESDAY AND SOUTHWEST WEDNESDAY. NEXT CHANCE FOR RAIN AND LOWER CIGS/VSBYS THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. GUSTY NORTH WINDS AS WELL AT 15-25 KNOTS. SKC/DRY WEATHER ON FRIDAY WITH HIGH PRESSURE ACROSS THE REGION AND WINDS NORTHEAST 10-15 KNOTS. && .MARINE... SHORT TERM /TODAY AND TONIGHT/... UPDATE THIS MORNING TO ADD THE ALBEMARLE SOUND TO THE GALE WARNING. FORECAST WIND GUSTS WERE ALREADY AT OR NEAR CRITERIA. CONCERN OVER THE 12MB/6HR PRESSURE RISES EXPECTED THIS AFTERNOON IMMEDIATELY BEHIND THE ARCTIC FRONT. BELIVE THIS WILL PUSH WINDS IN THE ALBEMARLE AND NORTHERN ALLIGATOR RIVER TO AT LEAT LOW END GALES FOR SEVERAL HOURS. ALSO BUMBED UP WAVE HEIGHTS OVER THE SOUND. OTHERWISE NO SIGNIFICANT CHANGES THIS MORNING. S/SW WINDS SHOULD CONTINUE TO RAMP UP OVER THE NEXT FEW HOURS PER THE LATEST HRRR. GUSTIMNESS OVER THE SOUTEHR WATERS AS WELL AS ALONG THE OUTER BANKS HAS BEEN INCREASING TO 30 TO 40 KT ALREADY. AHEAD OF STRONG COLD FRONT...GALE CONDITIONS ARE EXPECTED ON THE COASTAL WATERS AND SOUNDS TODAY. SMALL CRAFT ADVISORIES CONTINUE ON THE RIVERS INTO LATE TONIGHT. THE COOL HIGH PRESSURE BUILDS IN VERY QUICKLY BEHIND THE FRONT...AND WINDS WILL DROP OFF FAIRLY QUICKLY. PER LOCAL SWAN MODEL...SEAS WILL REMAIN ELEVATED ON THE COASTAL WATERS INTO TUESDAY. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...CONDITIONS WILL BE IMPROVING TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. THE PRESSURE GRADIENT LOOSENS QUICKLY SO WINDS/SEAS WILL DIMINISH RAPIDLY. THE HIGH WILL BE CENTERED OVER THE AREA TUESDAY NIGHT THEN SHIFTS OFFSHORE WEDNESDAY WITH LIGHT WINDS AND SEAS. CONDITIONS BEGIN TO WORSEN WEDNESDAY NIGHT AND THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. STRONG NORTH FLOW THURSDAY WITH SMALL CRAFT CONDITIONS FORECAST FOR ALL WATERS THURSDAY INCLUDING SOUNDS AND RIVERS...WITH GALE CONDITIONS POSSIBLE IN THE OREGON INLET TO OCRACOKE WATERS BUT HAVE CAPPED WINDS AT 30 KNOTS FOR NOW. THE LOW MOVES QUICKLY OFF TO THE NORTHEAST THURSDAY NIGHT AND HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY. ONCE AGAIN THE PRESSURE GRADIENT LOOSENS QUICKLY WITH WINDS AND SEAS DECREASING RAPIDLY AS A RESULT. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR NCZ103-104. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR AMZ136- 137. GALE WARNING UNTIL 10 PM EST THIS EVENING FOR AMZ130-131-135. GALE WARNING UNTIL 1 AM EST TUESDAY FOR AMZ150-152-154-156-158. && $$ SYNOPSIS... NEAR TERM... SHORT TERM... LONG TERM... AVIATION... MARINE...
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
ISSUED BY NATIONAL WEATHER SERVICE WAKEFIELD VA 934 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE THIS AFTERNOON. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY AND MOVE OFFSHORE TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS THE AREA WEDNESDAY NIGHT. LOW PRESSURE WILL DEVELOP ON THE FRONT OFFSHORE OF THE COAST THURSDAY AND MOVE AWAY THE REGION FRIDAY. HIGH PRESSURE WILL RE-BUILD OVER THE REGION NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 930 AM MONDAY...FORECAST UPDATED TO RAISE TEMPS/DEWPOINTS A FEW DEGREES IN MANY AREAS...PLUS INCREASE POPS TO CATEGORICAL EVERYWHERE THROUGH MIDDAY AS RAIN OVERSPREADS THE ENTIRE FA. AS OF 650 AM MONDAY...WIDESPREAD RAIN CONTINUES OVER THE REGION...ESPECIALLY THE COASTAL PLAINS AS RAIN COVERAGE HAS DIMINISHED A BIT AT THE COAST. LATEST 3KM HRRR SHOWS THE RAIN FILLING BACK IN THROUGH LATE MORNING AND HAVE CONTINUED LIKELY TO CATEGORICAL POPS INTO EARLY AFTERNOON. COLD FRONT CURRENTLY WORKING THROUGH THE TENNESSEE VALLEY SHOULD ARRIVE AROUND MIDDAY AND MOVE OFFSHORE BY EARLY AFTERNOON...ENDING THE BULK OF THE PRECIPITATION AS THE UPPER LEVELS GRADUALLY DRY THROUGH 00Z OR SO. HAVE LIKELY TO CATEGORICAL POPS THROUGH ABOUT NOON...THEN GRADUALLY TAPERING EAST TO WEST WITH ALL THREAT OF PRECIPITATION ENDED BY 00Z AND SKIES CLEARING RAPIDLY AS DEEP DRY AIR MIXES TO THE SURFACE. GUSTY WINDS BOTH AHEAD AND BEHIND THE COLD FRONT MAY GUST TO 35 MPH ON THE OUTER BANKS AND WILL ISSUE A WIND ADVISORY FROM 17Z TO 00Z FOR THAT AREA. DESPITE CLOUDS...WARM ADVECTION HAS ALLOWED TEMPS TO RISE OVERNIGHT AND TEMPS WILL CONTINUE TO RISE TO AROUND 60 OVER A GOOD PORTION OF THE AREA TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH WEDNESDAY/... AS OF 4 PM MONDAY...HIGH PRESSURE WILL BUILD IN BEHIND THE COLD FRONT TONIGHT WITH TEMPERATURES DROPPING INTO THE MID/UPPER 20S OVER MOST LAND AREAS TO RIGHT AROUND FREEZING ON THE OUTER BANKS. WINDS SHOULD SUBSIDE TOWARD MORNING...BUT THE REMAINING BREEZE WILL PUSH APPARENT TEMPERATURE VALUES INTO THE TEENS EARLY TUESDAY MORNING UNDER GENERALLY CLEAR SKIES. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 3 AM MON...THE EXTENDED PERIOD BEGINS DRY AS A SURFACE RIDGE PASSES THROUGH THE REGION TUESDAY AND MOVES OFF THE COAST WEDNESDAY. AN UPPER LEVEL DISTURBANCE OVER THE NORTHERN PLAINS WILL MOVE SOUTHEAST WEDNESDAY NIGHT AND THURSDAY WILL COMBINE WITH A SOUTHERN STREAM DISTURBANCE MOVING ACROSS THE NORTHERN GULF TO INDUCE LOW PRESSURE IN THE GULF OF MEXICO. THE LOW WILL PASS BY THE SOUTHEAST COAST AT THAT TIME BUT FORECAST TEMPS AND THICKNESSES INDICATE PRECIP WILL BE ALL RAIN. THE SYSTEM QUICKLY MOVES OFF TO THE NORTHEAST THURSDAY NIGHT WITH SURFACE HIGH PRESSURE BUILDING IN FOR FRIDAY AND SATURDAY. THE HIGH SHIFTS OFF THE COAST ON SUNDAY WITH THE NEXT SYSTEM ARRIVING ON MONDAY WITH A CHANCE OF RAIN. && .AVIATION /15Z MONDAY THROUGH FRIDAY/... SHORT TERM /THROUGH 12Z TUESDAY/... AS OF 655 AM MONDAY...LIGHT TO OCCASIONALLY MODERATE RAIN CONTINUES ACROSS EASTERN NC WITH MVFR CEILINGS AT KPGV. HOWEVER...VFR CONDITIONS REPORTED AT ALL OTHER TAF SITES. OTHER THAN PERHAPS A BRIEF PERIOD OF MVFR IN HEAVIER SHOWERS...EXPECT CONDITIONS TO REMAIN IN THE VFR RANGE THROUGH THE PERIOD. UPPER DRYING COMMENCES AROUND 18Z THROUGH THE EVENING AS SKIES CLEAR BY LATE EVENING. GUSTY SW WINDS WILL CONTINUE INTO AFTERNOON WITH WIND GUSTS 20-30KT...THIS COULD RESULT IN CROSSWIND IMPACTS AT EWN. THE COLD FRONT WILL MOVE THROUGH THE TERMINALS MONDAY AFTERNOON...WITH GUSTY WINDS BECOMING W/NW. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...VFR/SKC TUE THROUGH WED WITH WINDS LESS THAN 10 KNOTS...FROM THE NORTHWEST TUESDAY AND SOUTHWEST WEDNESDAY. NEXT CHANCE FOR RAIN AND LOWER CIGS/VSBYS THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. GUSTY NORTH WINDS AS WELL AT 15-25 KNOTS. SKC/DRY WEATHER ON FRIDAY WITH HIGH PRESSURE ACROSS THE REGION AND WINDS NORTHEAST 10-15 KNOTS. && .MARINE... SHORT TERM /TODAY AND TONIGHT/... AS OF 7 AM MONDAY...NO BIG CHANGES TO THE MARINE FORECAST. S/SW WINDS SHOULD CONTINUE TO RAMP UP OVER THE NEXT FEW HOURS PER THE LATEST HRRR. ALREADY VERY GUSTY AT DIAMOND BUOY...IN PROXIMITY TO 70 DEGREE WATER...WITH 35 KNOTS GUSTING TO 43 KNOTS. SEAS HAVE BUILD TO 10 FEET AT DIAMOND...AND WILL RESPOND ELSEWHERE OVER THE NEXT SEVERAL HOURS. AHEAD OF STRONG COLD FRONT...GALE CONDITIONS ARE EXPECTED ON THE COASTAL WATERS TODAY. CONDITIONS MAY BE A BIT MORE MARGINAL ON THE PAMLICO SOUND...BUT WILL KEEP GALES UP THERE AS WELL. SMALL CRAFT ADVISORIES CONTINUE ON THE REMAINING WATERS INTO LATE TONIGHT. THE COOL HIGH PRESSURE BUILDS IN VERY QUICKLY BEHIND THE FRONT...AND WINDS WILL DROP OFF FAIRLY QUICKLY. PER LOCAL SWAN MODEL...SEAS WILL REMAIN ELEVATED ON THE COASTAL WATERS INTO TUESDAY. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...CONDITIONS WILL BE IMPROVING TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. THE PRESSURE GRADIENT LOOSENS QUICKLY SO WINDS/SEAS WILL DIMINISH RAPIDLY. THE HIGH WILL BE CENTERED OVER THE AREA TUESDAY NIGHT THEN SHIFTS OFFSHORE WEDNESDAY WITH LIGHT WINDS AND SEAS. CONDITIONS BEGIN TO WORSEN WEDNESDAY NIGHT AND THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. STRONG NORTH FLOW THURSDAY WITH SMALL CRAFT CONDITIONS FORECAST FOR ALL WATERS THURSDAY INCLUDING SOUNDS AND RIVERS...WITH GALE CONDITIONS POSSIBLE IN THE OREGON INLET TO OCRACOKE WATERS BUT HAVE CAPPED WINDS AT 30 KNOTS FOR NOW. THE LOW MOVES QUICKLY OFF TO THE NORTHEAST THURSDAY NIGHT AND HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY. ONCE AGAIN THE PRESSURE GRADIENT LOOSENS QUICKLY WITH WINDS AND SEAS DECREASING RAPIDLY AS A RESULT. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR NCZ103-104. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR AMZ136- 137. GALE WARNING UNTIL 10 PM EST THIS EVENING FOR AMZ130-131-135. GALE WARNING UNTIL 1 AM EST TUESDAY FOR AMZ150-152-154-156-158. && $$ SYNOPSIS...CTC NEAR TERM...CTC SHORT TERM...CTC LONG TERM...HSA AVIATION...CTC/HSA MARINE...CTC/HSA
AREA FORECAST DISCUSSION
NWS NEWPORT/MOREHEAD CITY NC
659 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE OFFSHORE THIS AFTERNOON. COOL HIGH PRESSURE WILL BUILD IN FROM THE WEST TUESDAY AND MOVE OFFSHORE TUESDAY NIGHT. ANOTHER COLD FRONT WILL CROSS THE AREA WEDNESDAY NIGHT. LOW PRESSURE WILL DEVELOP ON THE FRONT OFFSHORE OF THE COAST THURSDAY AND MOVE AWAY THE REGION FRIDAY. HIGH PRESSURE WILL RE-BUILD OVER THE REGION NEXT WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... AS OF 650 AM MONDAY...WIDESPREAD RAIN CONTINUES OVER THE REGION...ESPECIALLY THE COASTAL PLAINS AS RAIN COVERAGE HAS DIMINISHED A BIT AT THE COAST. LATEST 3KM HRRR SHOWS THE RAIN FILLING BACK IN THROUGH LATE MORNING AND HAVE CONTINUED LIKELY TO CATEGORICAL POPS INTO EARLY AFTERNOON. COLD FRONT CURRENTLY WORKING THROUGH THE TENNESSEE VALLEY SHOULD ARRIVE AROUND MIDDAY AND MOVE OFFSHORE BY EARLY AFTERNOON...ENDING THE BULK OF THE PRECIPITATION AS THE UPPER LEVELS GRADUALLY DRY THROUGH 00Z OR SO. HAVE LIKELY TO CATEGORICAL POPS THROUGH ABOUT NOON...THEN GRADUALLY TAPERING EAST TO WEST WITH ALL THREAT OF PRECIPITATION ENDED BY 00Z AND SKIES CLEARING RAPIDLY AS DEEP DRY AIR MIXES TO THE SURFACE. GUSTY WINDS BOTH AHEAD AND BEHIND THE COLD FRONT MAY GUST TO 35 MPH ON THE OUTER BANKS AND WILL ISSUE A WIND ADVISORY FROM 17Z TO 00Z FOR THAT AREA. DESPITE CLOUDS...WARM ADVECTION HAS ALLOWED TEMPS TO RISE OVERNIGHT AND TEMPS WILL CONTINUE TO RISE TO AROUND 60 OVER A GOOD PORTION OF THE AREA TODAY. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/... AS OF 4 PM MONDAY...HIGH PRESSURE WILL BUILD IN BEHIND THE COLD FRONT TONIGHT WITH TEMPERATURES DROPPING INTO THE MID/UPPER 20S OVER MOST LAND AREAS TO RIGHT AROUND FREEZING ON THE OUTER BANKS. WINDS SHOULD SUBSIDE TOWARD MORNING...BUT THE REMAINING BREEZE WILL PUSH APPARENT TEMPERATURE VALUES INTO THE TEENS EARLY TUESDAY MORNING UNDER GENERALLY CLEAR SKIES. && .LONG TERM /TUESDAY THROUGH SUNDAY/... AS OF 3 AM MON...THE EXTENDED PERIOD BEGINS DRY AS A SURFACE RIDGE PASSES THROUGH THE REGION TUESDAY AND MOVES OFF THE COAST WEDNESDAY. AN UPPER LEVEL DISTURBANCE OVER THE NORTHERN PLAINS WILL MOVE SOUTHEAST WEDNESDAY NIGHT AND THURSDAY WILL COMBINE WITH A SOUTHERN STREAM DISTURBANCE MOVING ACROSS THE NORTHERN GULF TO INDUCE LOW PRESSURE IN THE GULF OF MEXICO. THE LOW WILL PASS BY THE SOUTHEAST COAST AT THAT TIME BUT FORECAST TEMPS AND THICKNESSES INDICATE PRECIP WILL BE ALL RAIN. THE SYSTEM QUICKLY MOVES OFF TO THE NORTHEAST THURSDAY NIGHT WITH SURFACE HIGH PRESSURE BUILDING IN FOR FRIDAY AND SATURDAY. THE HIGH SHIFTS OFF THE COAST ON SUNDAY WITH THE NEXT SYSTEM ARRIVING ON MONDAY WITH A CHANCE OF RAIN. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... SHORT TERM /THROUGH 12Z TUESDAY/... AS OF 655 AM MONDAY...LIGHT TO OCCASIONALLY MODERATE RAIN CONTINUES ACROSS EASTERN NC WITH MVFR CEILINGS AT KPGV. HOWEVER...VFR CONDITIONS REPORTED AT ALL OTHER TAF SITES. OTHER THAN PERHAPS A BRIEF PERIOD OF MVFR IN HEAVIER SHOWERS...EXPECT CONDITIONS TO REMAIN IN THE VFR RANGE THROUGH THE PERIOD. UPPER DRYING COMMENCES AROUND 18Z THROUGH THE EVENING AS SKIES CLEAR BY LATE EVENING. GUSTY SW WINDS WILL CONTINUE INTO AFTERNOON WITH WIND GUSTS 20-30KT...THIS COULD RESULT IN CROSSWIND IMPACTS AT EWN. THE COLD FRONT WILL MOVE THROUGH THE TERMINALS MONDAY AFTERNOON...WITH GUSTY WINDS BECOMING W/NW. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...VFR/SKC TUE THROUGH WED WITH WINDS LESS THAN 10 KNOTS...FROM THE NORTHWEST TUESDAY AND SOUTHWEST WEDNESDAY. NEXT CHANCE FOR RAIN AND LOWER CIGS/VSBYS THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. GUSTY NORTH WINDS AS WELL AT 15-25 KNOTS. SKC/DRY WEATHER ON FRIDAY WITH HIGH PRESSURE ACROSS THE REGION AND WINDS NORTHEAST 10-15 KNOTS. && .MARINE... SHORT TERM /TODAY AND TONIGHT/... AS OF 7 AM MONDAY...NO BIG CHANGES TO THE MARINE FORECAST. S/SW WINDS SHOULD CONTINUE TO RAMP UP OVER THE NEXT FEW HOURS PER THE LATEST HRRR. ALREADY VERY GUSTY AT DIAMOND BUOY...IN PROXIMITY TO 70 DEGREE WATER...WITH 35 KNOTS GUSTING TO 43 KNOTS. SEAS HAVE BUILD TO 10 FEET AT DIAMOND...AND WILL RESPOND ELSEWHERE OVER THE NEXT SEVERAL HOURS. AHEAD OF STRONG COLD FRONT...GALE CONDITIONS ARE EXPECTED ON THE COASTAL WATERS TODAY. CONDITIONS MAY BE A BIT MORE MARGINAL ON THE PAMLICO SOUND...BUT WILL KEEP GALES UP THERE AS WELL. SMALL CRAFT ADVISORIES CONTINUE ON THE REMAINING WATERS INTO LATE TONIGHT. THE COOL HIGH PRESSURE BUILDS IN VERY QUICKLY BEHIND THE FRONT...AND WINDS WILL DROP OFF FAIRLY QUICKLY. PER LOCAL SWAN MODEL...SEAS WILL REMAIN ELEVATED ON THE COASTAL WATERS INTO TUESDAY. LONG TERM /TUESDAY THROUGH FRIDAY/... AS OF 3 AM MON...CONDITIONS WILL BE IMPROVING TUESDAY AS HIGH PRESSURE BUILDS IN FROM THE WEST. THE PRESSURE GRADIENT LOOSENS QUICKLY SO WINDS/SEAS WILL DIMINISH RAPIDLY. THE HIGH WILL BE CENTERED OVER THE AREA TUESDAY NIGHT THEN SHIFTS OFFSHORE WEDNESDAY WITH LIGHT WINDS AND SEAS. CONDITIONS BEGIN TO WORSEN WEDNESDAY NIGHT AND THURSDAY AS LOW PRESSURE PASSES BY OFFSHORE. STRONG NORTH FLOW THURSDAY WITH SMALL CRAFT CONDITIONS FORECAST FOR ALL WATERS THURSDAY INCLUDING SOUNDS AND RIVERS...WITH GALE CONDITIONS POSSIBLE IN THE OREGON INLET TO OCRACOKE WATERS BUT HAVE CAPPED WINDS AT 30 KNOTS FOR NOW. THE LOW MOVES QUICKLY OFF TO THE NORTHEAST THURSDAY NIGHT AND HIGH PRESSURE BUILDS IN FROM THE WEST FRIDAY. ONCE AGAIN THE PRESSURE GRADIENT LOOSENS QUICKLY WITH WINDS AND SEAS DECREASING RAPIDLY AS A RESULT. && .TIDES/COASTAL FLOODING... AS OF 4 AM MON...STRONG SSW WINDS WILL CONTINUE TODAY WITH WINDS BECOMING NW LATER IN THE AFTERNOON. MINOR WATER LEVEL RISES WILL BE POSSIBLE FOR SOUNDSIDE AREAS ADJACENT TO THE PAMLICO SOUND...MAINLY BEHIND THE FRONT LATE TODAY. MINOR LOW WATER WILL ALSO BE POSSIBLE THIS AFTERNOON AND TONIGHT OVER THE WESTERN PAMLICO SOUND AND RIVERS. && .MHX WATCHES/WARNINGS/ADVISORIES... NC...WIND ADVISORY FROM NOON TODAY TO 7 PM EST THIS EVENING FOR NCZ103-104. MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR AMZ136- 137. GALE WARNING UNTIL 10 PM EST THIS EVENING FOR AMZ135. SMALL CRAFT ADVISORY UNTIL 3 AM EST TUESDAY FOR AMZ130-131. GALE WARNING UNTIL 1 AM EST TUESDAY FOR AMZ152-154-156-158. GALE WARNING FROM 3 PM THIS AFTERNOON TO 1 AM EST TUESDAY FOR AMZ150. && $$ SYNOPSIS...CTC NEAR TERM...CTC SHORT TERM...CTC LONG TERM...HSA AVIATION...CTC/HSA MARINE...CTC/HSA TIDES/COASTAL FLOODING...
AREA FORECAST DISCUSSION
NWS BISMARCK ND
935 AM CST MON FEB 2 2015 .UPDATE... ISSUED AT 928 AM CST MON FEB 2 2015 UPDATED THE FORECAST TO INCREASE SNOW TO LIKELY THROUGH THE NEXT 2 HOURS IN THE AREAS SHOWING SNOW ACROSS THE SOUTHWEST. STILL EXPECTING ONLY TRACE AMOUNTS TO MAYBE A HALF INCH OF SNOW. UPDATE ISSUED AT 644 AM CST MON FEB 2 2015 LOW PRESSURE OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING WITH A WEAK INVERTED TROUGH INTO NORTHWEST NORTH DAKOTA WILL MOVE SOUTHEAST TODAY. LIGHT SNOW OVER A GOOD PORTION OF EASTERN MONTANA IS JUST BEGINNING TO MOVE INTO WESTERN NORTH DAKOTA. CURRENT FORECAST LOOKS IN GOOD SHAPE WITH LIGHT SNOW MAINLY OVER THE WEST AND FAR SOUTH CENTRAL DURING THE MORNING HOURS...TAPERING OFF IN THE FAR SOUTHWEST AND SOUTH CENTRAL THIS AFTERNOON. DID BUMP UP POPS TO LIKELY ALONG THE MONTANA BORDER THIS MORNING. LOWS HAVE BEEN REACHED AS TEMPERATURES ARE RISING ACROSS THE FORECAST AREA. UPDATED LATEST SENSIBLE WEATHER ELEMENTS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FOCUS FOR THE SHORT TERM IS LIGHT SNOW. A WEAK UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW CURRENTLY OVER MONTANA WILL CONTINUE TO PROPAGATE SOUTHEAST THIS MORNING...EVENTUALLY SKIRTING SOUTHWEST NORTH DAKOTA. REGIONAL RADAR IS SHOWING SOME LIGHT BANDS OF SNOW ACROSS CENTRAL AND EASTERN MONTANA ASSOCIATED WITH THIS LOW. THIS AREA OF SNOW IS EXPECTED TO SLOWLY SAG SOUTH AND EAST THROUGH THE MORNING HOURS. THE MAIN QUESTION IS WHETHER OR NOT THIS AREA OF SNOW WILL HOLD TOGETHER AND HOW FAR EAST IT WILL MOVE. LATEST SHORT TERM GUIDANCE SUGGESTS THAT THE AREA OF SNOW WILL BRUSH WESTERN AND SOUTHERN NORTH DAKOTA THIS MORNING BUT WILL DIMINISH IN INTENSITY LEAVING ONLY A DUSTING TO LESS THAN A HALF INCH OF SNOW ACROSS PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA. FEEL THE 09 UTC HRRR HAS A PRETTY GOOD HANDLE ON THE SITUATION AS IT IS PRETTY CLOSE IN DEPICTING CURRENT SNOW BANDS IN EASTERN MONTANA. THE 09 UTC HRRR CONTINUES TO BRING THAT BAND OF SNOW EASTWARD INTO WESTERN NORTH DAKOTA THIS MORNING...BUT DIMINISHES AND SCATTERS OUT THE SNOW LATER THIS MORNING. FROM THERE OUR ATTENTION TURNS TO TONIGHT WHEN WE HAVE YET ANOTHER CHANCE FOR SNOW. ALL THE MAJOR MODELS ARE SHOWING A WELL DEFINED AREA OF SNOW ENTERING THE REGION AROUND MIDNIGHT AND SPREADING SOUTH AND EAST THROUGH THE DAY TUESDAY. THE MODELS ARE ALSO CONSISTENT WITH RESPECT TO LOCATION AND AMOUNTS OF PRECIPITATION. AT THIS TIME IT APPEARS WEST CENTRAL NORTH DAKOTA IS THE MOST FAVORED LOCATION FOR SNOWFALL...WITH AROUND 2 INCHES TOTAL ACCUMULATION POSSIBLE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FORECAST CONCERNS IN THE LONG TERM ARE SNOW CHANCES TUESDAY AND TUESDAY NIGHT...AND THEN PRECIPITATION CHANCES AND TYPE FRIDAY THROUGH SATURDAY. DETERMINISTIC MODELS ARE IN REASONABLE AGREEMENT WITH THE SYSTEM MOVING THROUGH LATE MONDAY NIGHT AND TUESDAY. THE GFS IS THE OUTLIER WITH THE QPF PLACEMENT WITH THIS SYSTEM. ALL OTHER MODELS ARE FARTHER NORTH AND EAST. UTILIZED A MODEL BLEND WITH THE NAM/SREF/GEM/ECMWF AND GFS. THUS NOT TOTALLY DISCOUNTING THE GFS TRACK BUT THIS DOES RESULT IN A LITTLE FARTHER NORTHERN TRACK WITH THE QPF. PREVIOUS TRACK HAD HIGHEST SNOW TOTALS FROM AROUND BEACH TO SOUTH OF BISMARCK AND IS NOW BETWEEN BEACH AND WILLISTON...THROUGH BISMARCK...TO ELLENDALE. AND WITH LESSER AMOUNTS IN THE FAR SOUTHWEST. OVERALL NOT A BIG CHANGE AND GENERALLY 1-2 INCHES OVER ALL BUT THE FAR SOUTHWEST WHERE ACCUMULATIONS MAY TOTAL AN INCH OR LESS...AND THE FAR NORTH CENTRAL FROM SHERWOOD AND MOHALL TO RUGBY AND NORTH WHERE AMOUNTS ARE EXPECTED TO BE A HALF INCH OR LESS. OF COURSE THE RESULTING TRACK IS STILL SUBJECT TO CHANGE...BUT THE TOTAL SNOW AMOUNTS HAVE BEEN VERY CONSISTENT FOR THE PAST TWO DAYS. AFTER A DRY PERIOD WEDNESDAY THROUGH THURSDAY NIGHT WE SEE ANOTHER SERIES OF IMPULSES MOVING THROUGH A STRONG NORTHWEST FLOW FRIDAY THROUGH SATURDAY NIGHT AND INTERACTING WITH THE BAROCLINIC ZONE. BY THIS TIME THE BAROCLINIC ZONE HAS SHIFTED FARTHER NORTH OVER NORTHERN INTO EASTERN NORTH DAKOTA. THERE ARE ALREADY TIMING DIFFERENCES WITH THE GFS MUCH QUICKER WITH THE FIRST IMPULSE AND ITS ASSOCIATED SURFACE LOW MOVING THROUGH MUCH QUICKER ON FRIDAY THAN BOTH THE ECMWF/GEM. THERE ARE ALSO DIFFERENCES IN THE EVOLUTION OF THE BAROCLINIC ZONE AS THE ECMWF KEEPS IT FROM NORTHERN INTO EASTERN NORTH DAKOTA FRIDAY AND FRIDAY NIGHT...THEN SAGS IT SOUTH THROUGH ALL BUT THE FAR SOUTHWEST BY SATURDAY NIGHT. THE QUICKER GFS DROPS THE BZ SOUTH FRIDAY...LIFTS IT BACK NORTH ON SATURDAY AND DROPS IT BACK DOWN SATURDAY NIGHT BEHIND A QUICK MOVING CLIPPER. THE GEM BRINGS IT DOWN SLIGHTLY ON FRIDAY THEN BEGINS TO LIFT IT WELL NORTH OF THE STATE ON SATURDAY. WITH ALL THAT...SEE NO REASON AT THIS TIME TO DEVIATE FROM A MODEL BLEND FOR POPS WHICH BRINGS MAINLY CHANCE POPS TO THE NORTH FRIDAY AND THEN SOUTH ACROSS ALL BUT THE SOUTHWEST SATURDAY...AND EXITING TO THE EAST SATURDAY NIGHT. THE MAIN CONCERN HERE IS THAT THERE WILL PROBABLY BE A CHANCE OF SOME MIXED PRECIPITATION ON THE SOUTHERN PERIPHERY OF THE BAROCLINIC ZONE...WHEREVER IT MAY BE...AND THIS WILL HAVE TO BE MONITORED AS WE GO THROUGH THE WEEK. AS FAR AS TEMPERATURES ARE CONCERNED...WE REMAIN COLD ON TUESDAY AND WEDNESDAY. WIND CHILL HEADLINES WILL PROBABLY BE NEEDED LATE TUESDAY NIGHT INTO WEDNESDAY MORNING OVER THE NORTH CENTRAL. AS THE BAROCLINIC ZONE SHIFTS NORTH WE WARM INTO THE 20S NORTHEAST TO THE 40S SOUTHWEST. THEN FRIDAY THROUGH SUNDAY THE TEMPERATURE GRADIENT SHARPENS EVEN MORE WITH HIGHS IN THE SINGLE DIGITS AND LOW TEENS OVER THE TURTLE MOUNTAINS AREA IN THE NORTH CENTRAL...TO THE MID AND UPPER 40S OVER THE SOUTHWEST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 928 AM CST MON FEB 2 2015 VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF PERIOD. HOWEVER...KDIK MAY FALL TO MVFR CEILINGS AS LIGHT SNOW MOVES ACROSS THE SOUTHWEST THIS MORNING. LIGHT SNOW MAY MOVE INTO KBIS BY LATE MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...MM SHORT TERM...AJ LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS BISMARCK ND
644 AM CST MON FEB 2 2015 .UPDATE... ISSUED AT 644 AM CST MON FEB 2 2015 LOW PRESSURE OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING WITH A WEAK INVERTED TROUGH INTO NORTHWEST NORTH DAKOTA WILL MOVE SOUTHEAST TODAY. LIGHT SNOW OVER A GOOD PORTION OF EASTERN MONTANA IS JUST BEGINNING TO MOVE INTO WESTERN NORTH DAKOTA. CURRENT FORECAST LOOKS IN GOOD SHAPE WITH LIGHT SNOW MAINLY OVER THE WEST AND FAR SOUTH CENTRAL DURING THE MORNING HOURS...TAPERING OFF IN THE FAR SOUTHWEST AND SOUTH CENTRAL THIS AFTERNOON. DID BUMP UP POPS TO LIKELY ALONG THE MONTANA BORDER THIS MORNING. LOWS HAVE BEEN REACHED AS TEMPERATURES ARE RISING ACROSS THE FORECAST AREA. UPDATED LATEST SENSIBLE WEATHER ELEMENTS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FOCUS FOR THE SHORT TERM IS LIGHT SNOW. A WEAK UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW CURRENTLY OVER MONTANA WILL CONTINUE TO PROPAGATE SOUTHEAST THIS MORNING...EVENTUALLY SKIRTING SOUTHWEST NORTH DAKOTA. REGIONAL RADAR IS SHOWING SOME LIGHT BANDS OF SNOW ACROSS CENTRAL AND EASTERN MONTANA ASSOCIATED WITH THIS LOW. THIS AREA OF SNOW IS EXPECTED TO SLOWLY SAG SOUTH AND EAST THROUGH THE MORNING HOURS. THE MAIN QUESTION IS WHETHER OR NOT THIS AREA OF SNOW WILL HOLD TOGETHER AND HOW FAR EAST IT WILL MOVE. LATEST SHORT TERM GUIDANCE SUGGESTS THAT THE AREA OF SNOW WILL BRUSH WESTERN AND SOUTHERN NORTH DAKOTA THIS MORNING BUT WILL DIMINISH IN INTENSITY LEAVING ONLY A DUSTING TO LESS THAN A HALF INCH OF SNOW ACROSS PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA. FEEL THE 09 UTC HRRR HAS A PRETTY GOOD HANDLE ON THE SITUATION AS IT IS PRETTY CLOSE IN DEPICTING CURRENT SNOW BANDS IN EASTERN MONTANA. THE 09 UTC HRRR CONTINUES TO BRING THAT BAND OF SNOW EASTWARD INTO WESTERN NORTH DAKOTA THIS MORNING...BUT DIMINISHES AND SCATTERS OUT THE SNOW LATER THIS MORNING. FROM THERE OUR ATTENTION TURNS TO TONIGHT WHEN WE HAVE YET ANOTHER CHANCE FOR SNOW. ALL THE MAJOR MODELS ARE SHOWING A WELL DEFINED AREA OF SNOW ENTERING THE REGION AROUND MIDNIGHT AND SPREADING SOUTH AND EAST THROUGH THE DAY TUESDAY. THE MODELS ARE ALSO CONSISTENT WITH RESPECT TO LOCATION AND AMOUNTS OF PRECIPITATION. AT THIS TIME IT APPEARS WEST CENTRAL NORTH DAKOTA IS THE MOST FAVORED LOCATION FOR SNOWFALL...WITH AROUND 2 INCHES TOTAL ACCUMULATION POSSIBLE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FORECAST CONCERNS IN THE LONG TERM ARE SNOW CHANCES TUESDAY AND TUESDAY NIGHT...AND THEN PRECIPITATION CHANCES AND TYPE FRIDAY THROUGH SATURDAY. DETERMINISTIC MODELS ARE IN REASONABLE AGREEMENT WITH THE SYSTEM MOVING THROUGH LATE MONDAY NIGHT AND TUESDAY. THE GFS IS THE OUTLIER WITH THE QPF PLACEMENT WITH THIS SYSTEM. ALL OTHER MODELS ARE FARTHER NORTH AND EAST. UTILIZED A MODEL BLEND WITH THE NAM/SREF/GEM/ECMWF AND GFS. THUS NOT TOTALLY DISCOUNTING THE GFS TRACK BUT THIS DOES RESULT IN A LITTLE FARTHER NORTHERN TRACK WITH THE QPF. PREVIOUS TRACK HAD HIGHEST SNOW TOTALS FROM AROUND BEACH TO SOUTH OF BISMARCK AND IS NOW BETWEEN BEACH AND WILLISTON...THROUGH BISMARCK...TO ELLENDALE. AND WITH LESSER AMOUNTS IN THE FAR SOUTHWEST. OVERALL NOT A BIG CHANGE AND GENERALLY 1-2 INCHES OVER ALL BUT THE FAR SOUTHWEST WHERE ACCUMULATIONS MAY TOTAL AN INCH OR LESS...AND THE FAR NORTH CENTRAL FROM SHERWOOD AND MOHALL TO RUGBY AND NORTH WHERE AMOUNTS ARE EXPECTED TO BE A HALF INCH OR LESS. OF COURSE THE RESULTING TRACK IS STILL SUBJECT TO CHANGE...BUT THE TOTAL SNOW AMOUNTS HAVE BEEN VERY CONSISTENT FOR THE PAST TWO DAYS. AFTER A DRY PERIOD WEDNESDAY THROUGH THURSDAY NIGHT WE SEE ANOTHER SERIES OF IMPULSES MOVING THROUGH A STRONG NORTHWEST FLOW FRIDAY THROUGH SATURDAY NIGHT AND INTERACTING WITH THE BAROCLINIC ZONE. BY THIS TIME THE BAROCLINIC ZONE HAS SHIFTED FARTHER NORTH OVER NORTHERN INTO EASTERN NORTH DAKOTA. THERE ARE ALREADY TIMING DIFFERENCES WITH THE GFS MUCH QUICKER WITH THE FIRST IMPULSE AND ITS ASSOCIATED SURFACE LOW MOVING THROUGH MUCH QUICKER ON FRIDAY THAN BOTH THE ECMWF/GEM. THERE ARE ALSO DIFFERENCES IN THE EVOLUTION OF THE BAROCLINIC ZONE AS THE ECMWF KEEPS IT FROM NORTHERN INTO EASTERN NORTH DAKOTA FRIDAY AND FRIDAY NIGHT...THEN SAGS IT SOUTH THROUGH ALL BUT THE FAR SOUTHWEST BY SATURDAY NIGHT. THE QUICKER GFS DROPS THE BZ SOUTH FRIDAY...LIFTS IT BACK NORTH ON SATURDAY AND DROPS IT BACK DOWN SATURDAY NIGHT BEHIND A QUICK MOVING CLIPPER. THE GEM BRINGS IT DOWN SLIGHTLY ON FRIDAY THEN BEGINS TO LIFT IT WELL NORTH OF THE STATE ON SATURDAY. WITH ALL THAT...SEE NO REASON AT THIS TIME TO DEVIATE FROM A MODEL BLEND FOR POPS WHICH BRINGS MAINLY CHANCE POPS TO THE NORTH FRIDAY AND THEN SOUTH ACROSS ALL BUT THE SOUTHWEST SATURDAY...AND EXITING TO THE EAST SATURDAY NIGHT. THE MAIN CONCERN HERE IS THAT THERE WILL PROBABLY BE A CHANCE OF SOME MIXED PRECIPITATION ON THE SOUTHERN PERIPHERY OF THE BAROCLINIC ZONE...WHEREVER IT MAY BE...AND THIS WILL HAVE TO BE MONITORED AS WE GO THROUGH THE WEEK. AS FAR AS TEMPERATURES ARE CONCERNED...WE REMAIN COLD ON TUESDAY AND WEDNESDAY. WIND CHILL HEADLINES WILL PROBABLY BE NEEDED LATE TUESDAY NIGHT INTO WEDNESDAY MORNING OVER THE NORTH CENTRAL. AS THE BAROCLINIC ZONE SHIFTS NORTH WE WARM INTO THE 20S NORTHEAST TO THE 40S SOUTHWEST. THEN FRIDAY THROUGH SUNDAY THE TEMPERATURE GRADIENT SHARPENS EVEN MORE WITH HIGHS IN THE SINGLE DIGITS AND LOW TEENS OVER THE TURTLE MOUNTAINS AREA IN THE NORTH CENTRAL...TO THE MID AND UPPER 40S OVER THE SOUTHWEST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z TUESDAY MORNING) ISSUED AT 644 AM CST MON FEB 2 2015 VFR CONDITIONS ARE EXPECTED AT ALL TAF SITES THROUGH THE TAF PERIOD. LIGHT SNOW MAY ENTER KISN/KDIK TERMINALS EARLY THIS MORNING AND KBIS BY LATE MORNING. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...TWH SHORT TERM...AJ LONG TERM...TWH AVIATION...AJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
1102 AM EST MON FEB 2 2015 .SYNOPSIS... LOW PRESSURE EXITING NORTHEAST OF THE AREA...WHIPS COLD FRONT OVERNIGHT/EARLY MONDAY. HIGH PRESSURE CROSSES TUESDAY. NEXT COLD FRONT CROSSES WEDNESDAY NIGHT. HIGH PRESSURE CROSSES FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... 1045 AM UPDATE... ARCTIC FRONT PUSHING THRU THE MOUNTAINS AND SHOULD BE E OF CWA NEXT HR. STRONG GUSTY WINDS 35 TO 40 KTS CAN BE EXPECTED OVER THE HIGH TERRAIN NEXT FEW HRS AS STRONG CAA COMMENCES. ELSEWHERE...BACK EDGE OF STEADY LIGHT SNOW PUSHING THRU C WV ATTM WITH THE UPPER TROF. BEHIND IT...SCT SHSN EXTEND BACK INTO OH. TEMPS WILL CONTINUE TO FALL THROUGHOUT THE AFTERNOON...WITH GUSTY WINDS CREATING FOR LOW WIND CHILLS. FRESHENED UP THE SPS ALONG WITH STORM TOTAL SNOW GRAPHIC TO ACCOUNT FOR WHAT FELL LAST NIGHT IN POCAHONTAS COUNTY. NUDGED THE LOWLANDS TO BELOW AN INCH...MAINLY JUST DUSTINGS. PREVIOUS DISCUSSION BELOW... LOW PRESSURE CENTER EXITING NORTHEAST OF THE AREA THIS MORNING WITH WIDESPREAD RAIN ACROSS THE LOWLANDS MOVING EAST. EXPECT THE RAIN TO TRANSITION TO ALL SNOW DURING THE MORNING HOURS AS VERY COLD AIR...AS SEEN ON MODELS H85 TEMPERATURES DROPPING FROM 0C TO MINUS 15C THROUGH THE AFTERNOON HOURS. SO...EXPECT A NON DIURNAL TREND IN TEMPERATURES TODAY WITH RAIN CHANGING TO SNOW. STRONG NORTHWEST FLOW WILL TURN ON THE UPSLOPE MACHINE OVER THE NORTHEAST MOUNTAINS LATER TODAY INTO TONIGHT TO PRODUCE SIGNIFICANT SNOW ACCUMULATIONS. SREF PROBABILITIES SHOW 88 PERCENT FOR SNOW ACCUMULATIONS HIGHER THAN 4 INCHES THERE. THE GFS AND ECMWF SUPPORT PCPN UNDER VERY COLD CONDITIONS THROUGH 21Z NORTHEAST MOUNTAINS. THEREFORE...A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR POCAHONTAS...RANDOLPH AND WEBSTER COUNTIES UNTIL 7 PM. IN ADDITION...STRONG GUSTY WINDS COULD PRODUCE BLOWING SNOW LATER THIS AFTERNOON AND TONIGHT OVER THE NORTHEAST MOUNTAINS. THE COMBINATION OF WIND AND VERY COLD TEMPERATURES COULD PRODUCE WIND CHILLS INTO THE MINUS TEENS OVER THE HIGHEST PEAKS THROUGH TONIGHT. TEMPERATURES WILL DROP INTO THE TEENS TONIGHT. WENT WITH THE HRRR AND NAM FOR TEMPERATURES THROUGH THE PERIOD. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A COLD START TO THE MORNING ON TUESDAY BEFORE HIGH PRESSURE MOVES THROUGH THE AREA DURING THE DAY. A PRECIPITATION SHIELD FROM A MORE NORTHERLY SYSTEM WILL EXTEND DOWN TO JUST NORTH OF OUR FORECAST AREA...BUT KEPT OUR AREA DRY FOR NOW. A COLD FRONT SWINGS THROUGH THE AREA ON WED NIGHT INCREASING PRECIPITATION CHANCES ACROSS THE FORECAST AREA WHICH SHOULD BRING LIGHT RAIN IN THE AFTERNOON AND LIGHT SNOW IN THE EVENING. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD EASTERN MID/UPPER LEVEL TROF WITH FAST FLOW...AND FEW OPPORTUNITIES TO ACCESS THE GULF OF MEXICO MOISTURE. WEAK WARM AIR ADVECTION ONGOING TUESDAY NIGHT...WILL TRY TO BRING SOME 20/30 POPS A BIT FASTER SOUTH BY DAWN WEDNESDAY INTO OUR NORTHERN COUNTIES. 12Z GFS A BIT MORE AGGRESSIVE WITH THE MOISTURE MOVING UP THE OHIO VALLEY WEDNESDAY ALONG THAT FRONTAL BOUNDARY. ECMWF CERTAINLY NOT AS MOIST. FOR NOW...WILL KEEP POPS IN CHANCE CATEGORY WITH FRONT WEDNESDAY INTO WEDNESDAY NIGHT. HAVE COLDER AIR BLOWING SOUTH AGAIN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY. WENT COLDER THAN OUR PREVIOUS FORECAST. DRYING AGAIN THURSDAY NIGHT THRU FRIDAY NIGHT. IN THE FAST FLOW...NEXT SYSTEM COULD ARRIVE BY LATE DAY 7. && .AVIATION /16Z MONDAY THROUGH FRIDAY/... LOW PRESSURE EXITING THE AREA TO OUR NORTHEAST AND ASSOCIATED COLD FRONT CROSSING WV THIS MORNING WILL BRING A DRASTIC CHANGE IN TEMPERATURES CHANGING RAIN INTO ALL SNOW FROM WEST TO EAST. WINDS WILL GUST UP TO 25 KNOTS BEHIND THE COLD FRONT. STARTED WITH VFR CONDITIONS AT MOST PLACES TRANSITIONING TO MVFR AND EVEN IFR SPREADING FROM WEST TO EAST UNDER SNOW SHOWERS. EXPECT IFR CONDITIONS UNDER SNOW SHOWERS THROUGH MONDAY NIGHT. A GRADUAL IMPROVEMENT TO LOW VFR AFTER 22Z IS EXPECTED EXCEPT ACROSS EKN AND CKB WHERE SNOW SHOWERS WILL LAST LONGER. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIO: TIMING OF DROPS INTO MVFR AND IFR MAY VARY. CONDITIONS MAY IMPROVE TO LOW VFR SLOWER THAN CURRENTLY FORECAST LATER TODAY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 EST 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20 CRW CONSISTENCY H H H H H H H H H H H M HTS CONSISTENCY H H H H H H H M H H H H BKW CONSISTENCY H H H H H H H H H H M M EKN CONSISTENCY H H H H H H H H H M M M PKB CONSISTENCY H H H H H H H H H H M H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z TUESDAY... IFR POSSIBLE IN LIGHT SNOW WEDNESDAY NIGHT INTO THURSDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ038- 046-047. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/JW NEAR TERM...ARJ/30 SHORT TERM...JW LONG TERM...KTB AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS CHARLESTON WV
522 AM EST MON FEB 2 2015 .SYNOPSIS... LOW PRESSURE EXITING NORTHEAST OF THE AREA...WHIPS COLD FRONT OVERNIGHT/EARLY MONDAY. HIGH PRESSURE CROSSES TUESDAY. NEXT COLD FRONT CROSSES WEDNESDAY NIGHT. HIGH PRESSURE CROSSES FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... LOW PRESSURE CENTER EXITING NORTHEAST OF THE AREA THIS MORNING WITH WIDESPREAD RAIN ACROSS THE LOWLANDS MOVING EAST. EXPECT THE RAIN TO TRANSITION TO ALL SNOW DURING THE MORNING HOURS AS VERY COLD AIR...AS SEEN ON MODELS H85 TEMPERATURES DROPPING FROM 0C TO MINUS 15C THROUGH THE AFTERNOON HOURS. SO...EXPECT A NON DIURNAL TREND IN TEMPERATURES TODAY WITH RAIN CHANGING TO SNOW. STRONG NORTHWEST FLOW WILL TURN ON THE UPSLOPE MACHINE OVER THE NORTHEAST MOUNTAINS LATER TODAY INTO TONIGHT TO PRODUCE SIGNIFICANT SNOW ACCUMULATIONS. SREF PROBABILITIES SHOW 88 PERCENT FOR SNOW ACCUMULATIONS HIGHER THAN 4 INCHES THERE. THE GFS AND ECMWF SUPPORT PCPN UNDER VERY COLD CONDITIONS THROUGH 21Z NORTHEAST MOUNTAINS. THEREFORE...A WINTER WEATHER ADVISORY HAS BEEN ISSUED FOR POCAHONTAS...RANDOLPH AND WEBSTER COUNTIES UNTIL 7 PM. IN ADDITION...STRONG GUSTY WINDS COULD PRODUCE BLOWING SNOW LATER THIS AFTERNOON AND TONIGHT OVER THE NORTHEAST MOUNTAINS. THE COMBINATION OF WIND AND VERY COLD TEMPERATURES COULD PRODUCE WIND CHILLS INTO THE MINUS TEENS OVER THE HIGHEST PEAKS THROUGH TONIGHT. TEMPERATURES WILL DROP INTO THE TEENS TONIGHT. WENT WITH THE HRRR AND NAM FOR TEMPERATURES THROUGH THE PERIOD. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... A COLD START TO THE MORNING ON TUESDAY BEFORE HIGH PRESSURE MOVES THROUGH THE AREA DURING THE DAY. A PRECIPITATION SHIELD FROM A MORE NORTHERLY SYSTEM WILL EXTEND DOWN TO JUST NORTH OF OUR FORECAST AREA...BUT KEPT OUR AREA DRY FOR NOW. A COLD FRONT SWINGS THROUGH THE AREA ON WED NIGHT INCREASING PRECIPITATION CHANCES ACROSS THE FORECAST AREA WHICH SHOULD BRING LIGHT RAIN IN THE AFTERNOON AND LIGHT SNOW IN THE EVENING. && .LONG TERM /THURSDAY THROUGH SUNDAY/... BROAD EASTERN MID/UPPER LEVEL TROF WITH FAST FLOW...AND FEW OPPORTUNITIES TO ACCESS THE GULF OF MEXICO MOISTURE. WEAK WARM AIR ADVECTION ONGOING TUESDAY NIGHT...WILL TRY TO BRING SOME 20/30 POPS A BIT FASTER SOUTH BY DAWN WEDNESDAY INTO OUR NORTHERN COUNTIES. 12Z GFS A BIT MORE AGGRESSIVE WITH THE MOISTURE MOVING UP THE OHIO VALLEY WEDNESDAY ALONG THAT FRONTAL BOUNDARY. ECMWF CERTAINLY NOT AS MOIST. FOR NOW...WILL KEEP POPS IN CHANCE CATEGORY WITH FRONT WEDNESDAY INTO WEDNESDAY NIGHT. HAVE COLDER AIR BLOWING SOUTH AGAIN OVERNIGHT WEDNESDAY NIGHT INTO THURSDAY. WENT COLDER THAN OUR PREVIOUS FORECAST. DRYING AGAIN THURSDAY NIGHT THRU FRIDAY NIGHT. IN THE FAST FLOW...NEXT SYSTEM COULD ARRIVE BY LATE DAY 7. && .AVIATION /10Z MONDAY THROUGH FRIDAY/... LOW PRESSURE EXITING THE AREA TO OUR NORTHEAST AND ASSOCIATED COLD FRONT CROSSING WV THIS MORNING WILL BRING A DRASTIC CHANGE IN TEMPERATURES CHANGING RAIN INTO ALL SNOW FROM WEST TO EAST. WINDS WILL GUST UP TO 25 KNOTS BEHIND THE COLD FRONT. STARTED WITH VFR CONDITIONS AT MOST PLACES TRANSITIONING TO MVFR AND EVEN IFR SPREADING FROM WEST TO EAST UNDER SNOW SHOWERS. EXPECT IFR CONDITIONS UNDER SNOW SHOWERS THROUGH MONDAY NIGHT. A GRADUAL IMPROVEMENT TO LOW VFR AFTER 22Z IS EXPECTED EXCEPT ACROSS EKN AND CKB WHERE SNOW SHOWERS WILL LAST LONGER. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z TUESDAY... FORECAST CONFIDENCE: MEDIUM. ALTERNATE SCENARIO: TIMING OF DROPS INTO MVFR AND IFR MAY VARY. CONDITIONS MAY IMPROVE TO LOW VFR SLOWER THAN CURRENTLY FORECAST LATER TODAY. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 11 12 13 14 15 16 17 18 19 20 21 22 EST 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY L L H H H H H H H H H H EKN CONSISTENCY L L L H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY L L H H H H H H H H H H AFTER 12Z TUESDAY... IFR POSSIBLE IN LIGHT SNOW WEDNESDAY NIGHT INTO THURSDAY. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...WINTER WEATHER ADVISORY UNTIL 7 PM EST THIS EVENING FOR WVZ038- 046-047. OH...NONE. KY...NONE. VA...NONE. && $$ SYNOPSIS...ARJ/JW NEAR TERM...ARJ SHORT TERM...JW LONG TERM...KTB AVIATION...ARJ
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
650 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE ACROSS THE REGION TODAY. AHEAD OF THE FRONT THE REGION WILL SEE MIXED WINTRY PRECIPITATION THIS MORNING...WITH A MIXTURE OF FREEZING RAIN AND RAIN ACROSS THE SOUTHERN HALF OF THE AREA...WHILE NORTH OF INTERSTATE 80 MOST OF THE PRECIPITATION WILL REMAIN AS SNOW. BEHIND THE FRONT THIS AFTERNOON WILL DROP RAPIDLY ALONG WITH GUSTY WINDS. THE COLD AIR WILL BE SHORT LIVED AS TEMPERATURES WILL RISE ABOVE FREEZING ACROSS MOST OF THE AREA ON WEDNESDAY, ACCOMPANIED BY A CHANCE OF SNOW ACROSS THE WEST. THE ROLLER COASTER OF TEMPERATURES WILL CONTINUE FOR THE REST OF THE WEEK AS ANOTHER SHORT LIVED BUT SIGNIFICANT COOL DOWN IS EXPECTED ON THURSDAY AND FRIDAY WITH SOME OF THE COLDEST TEMPERATURES OF THE SEASON POSSIBLE FRIDAY MORNING. TEMPERATURES WILL MODERATING BY THE THE WEEKEND. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 630AM UPDATE...REPORTS THAT SLEET AND LIGHT FZRA HAS MADE IT NORTH TO NY BORDER IN WARREN COUNTY...SO UPDATED TO EXTEND MIXED PRECIP ZONE TO CWA BORDER. OTHERWISE FORECAST ON TRACK...WITH COLD FRONT APPROACHING CWA AND RADAR ECHOES STARTING TO DECREASE. PREVIOUS DISCUSSION...TRANSITION TO FREEZING RAIN AND RAIN HAS OCCURRED SOUTH OF INTERSTATE 80. THE CHANGEOVER OCCURRED AT WFO AT 0720Z WITH SNOW ABRUPTLY TURNING TO FZ RAIN. WILL KEEP WSW FOR WINTRY CONDITIONS...THOUGH SNOW AMOUNTS WILL BE LESS THEN FORECAST ACROSS PORTIONS OF THE AREA. DID RAISE FZ RAIN ACCUMULATIONS ACROSS SOUTHERN PORTION OF WSW. PRECIP WILL CUT OFF QUICKLY AFTER 12Z PER HRRR OUTPUT. LAUREL HIGHLANDS OBS SHOW TEMPERATURES ABOVE FREEZING IS SPOTS AND EXPECT TEMPERATURES TO WARM CLOSE TO OR ABOVE FREEZING IN THE NEXT SEVERAL HOURS. COLD FRONT APPROACHING FROM W WILL BRING FALLING TEMPERATURES THIS AFTERNOON ALONG WITH SNOW SHOWERS OVER HIGHER ELEVATIONS IN WESTERN COUNTIES. WINDS WILL ALSO BE STRONG...CLOSE TO ADVISORY CRITERIA AT TIMES. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/... MUCH MORE QUIET WEATHER PATTERN AS COLD HIGH PRESSURE QUICKLY BUILDS INTO THE STATE. LOWS WILL FALL BELOW 0 OVERNIGHT CLOSEST TO NYS BORDER WHERE FRESH SNOW COVER WILL AID IN THE COOLING. ELSEWHERE MUCH OF THE AREA WILL SEE SINGLE DIGIT AND TEENS FOR LOWS. TUESDAY WILL BE A COLD AND DRY DAY WITH HIGHS STRUGGLING TO LEAVE THE TEENS AND TWENTIES. && .LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/... ENSEMBLE MEAN 5H PATTERN SHOWS AN ALBERTA CLIPPER DIVING SE INTO THE REGION WED/THU. ALL MED RANGE GUIDANCE TRACKS ASSOC SFC LOW NORTH OF THE STATE EARLY WED...LIKELY PRODUCING A BIT OF LGT SNOW ACROSS NORTHERN PA. A WEAK LOW ON TRAILING COLD FRONT COULD SUPPORT SOME LINGERING LGT SNOW ACROSS THE REGION /MAINLY ALLEGHENIES/ INTO EARLY THURSDAY. MODERATING TEMPS AHEAD OF CLIPPER COULD RESULT IN A DAY OF NEAR NORMAL HIGHS WEDNESDAY. HOWEVER...A REINFORCING SHOT OF ARCTIC AIR LOOKS NEARLY CERTAIN BEHIND CLIPPER LATE THIS WEEK. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS THE PRECIPITATION CONTINUES TO TRANSITION BETWEEN SNOW...SLEET AND FREEZING RAIN...THE VSBY RESTRICTIONS ARE VARYING. WITH BFD...JST...AOO...LNS AND MDT AT IFR OR LOWER. UNV AND IPT ARE JUST ABOVE...THOUGH GIVEN THE LOW CIGS UNV IS CLOSE AND SHOULD WAVER INTO IFR AT TIMES THROUGH 14Z. LOW CIGS WILL CONTINUE THROUGH MID MORNING AS THE RESULT OF MOIST SE FLOW ASCENDING THE HIGHER TERRAIN. MARGINAL LLWS WILL DEVELOP ACROSS SOUTHERN PA AS CORE OF STRONG WINDS ALOFT SLIDES ACROSS THE AREA. MARKED IMPROVEMENT IS EXPECTED BTWN 15Z-18Z MONDAY...AS LOW PRES PASSES EAST OF THE AREA...AND DRIER NW FLOW DEVELOPS. FOCUS WILL SHIFT TOWARD STRONG GUSTY WINDS MON AFTERNOON AND EVENING. GUSTS TO ARND 40KTS ARE POSSIBLE MON AFTN AND EVENING...AS STRENGTHENING STORM SYSTEM PASSES EAST OF PA. OUTLOOK... MON...AM RAIN/SNOW AND LOW CIGS. PM GUSTY NW WINDS. TUE...NO SIG WX EXPECTED. WED...AM LGT SNOW POSSIBLE NW MTNS. THU...AM LGT SNOW POSSIBLE. FRI...NO SIG WX EXPECTED. && .CTP WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR PAZ004>006-010>012-017>019-037-041-042-045-046-049>053-058. WINTER WEATHER ADVISORY UNTIL 8 AM EST THIS MORNING FOR PAZ033>036-064>066. WINTER STORM WARNING UNTIL 8 AM EST THIS MORNING FOR PAZ024>028-056-057-059-063. && $$ SYNOPSIS...ROSS/DANGELO NEAR TERM...ROSS SHORT TERM...ROSS LONG TERM...ROSS/FITZGERALD AVIATION...CERU/RXR
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
644 AM EST MON FEB 2 2015 .SYNOPSIS... A COLD FRONT WILL MOVE EAST OF THE WESTERN CAROLINAS AND NORTHEAST GEORGIA THIS MORNING...USHERING IN COLD AND WINDY CONDITIONS. COOL AND DRY HIGH PRESSURE WILL BUILD IN THE WAKE OF THE FRONT THROUGH TUESDAY AND LINGER INTO EARLY WEDNESDAY. ANOTHER COLD FRONT WILL MOVE INTO THE AREA FROM THE NORTHWEST ON THURSDAY...WITH DRY HIGH PRESSURE SPREADING BACK OVER THE REGION BY THE END OF THE WORK WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM EST...THE SFC COLD FRONT MOVING THROUGH THE FORECAST AREA WAS ANALYZED ALONG THE ERN SLOPES OF THE SRN APPALACHIANS AROUND DAYBREAK. THIS BOUNDARY SHOULD STEADILY MOVE EAST AND CLEAR THE KCLT METRO AREA CIRCA 15Z. HIGH POPS WILL CONTINUE FOR A COUPLE OF HOURS ALONG THE ERN PIEDMONT...BUT THUNDER NOW LOOKS LESS LIKELY AND PRECIPITATION SHOULD RAMP DOWN QUICKLY FOR MOST OF THE AREA AS A DRY SLOT WRAPS IN FROM THE SOUTHWEST. WINDS WILL COME UP RAPIDLY IN THE COLD ADVECTION POST FROPA FLOW...AND UPSLOPE MOISTURE WILL INCREASE SNOW SHOWER RATES OVER THE WRN MTNS AS SNOW LEVELS FALL THIS MORNING. THE CURRENT WINTER WEATHER AND WIND ADVISORIES LOOK WELL PLACED...WITH HIGH ELEVATION SNOW ACCUMS OF 1 TO 3 INCHES TODAY...VERY LITTLE IN THE VALLEYS...AND WIND GUSTS OF 40 TO 50 MPH LIKELY ACROSS THE HIGH TERRAIN. THE EASTWARD EXTENT OF ADVISORY LEVEL WINDS REMAINS THE PRIMARY TROUBLE SPOT IN THE FORECAST. THE LATEST RAP PROFILES SHOW 40+ KT WINDS ATOP THE MIXED LAYER THIS AFTERNOON FROM KGSO TO KHKY...BUT WITH SLIGHTLY LESSER VALUES FROM KCLT TO KGSP AND INTO GA. WILL CONTINUE THE CURRENT ADVISORIES...BUT ADDITIONAL COUNTIES MAY HAVE TO BE TACKED ON TO THE EAST IF ANY FURTHERN STRENGTHENING TRENDS ARE NOTED. NW FLOW MOISTURE AT LOW LEVELS WILL DRY UP QUICKLY THIS EVENING. EXPECT WESTERLY FLOW ALOFT AHEAD OF THE NEXT SWIFTLY MOVING BUT SHALLOW CLIPPER WAVE TONIGHT. MIN TEMPS WILL FALL INTO THE TEENS AND 20S ACROSS THE REGION. BLACK ICE CONCERNS WILL CONTINUE IN THE MTNS. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... AS OF 130 AM MONDAY...SFC HIGH PRESSURE WILL DOMINATE OVER THE SOUTHEAST TUE. A FAST MOVING SHORTWAVE WILL CROSS THE AREA EARLY IN THE DAY BUT WITH LITTLE MOISTURE TO WORK WITH...ONLY A FEW HIGH CLOUDS ARE EXPECTED TO RESULT FROM ITS PASSAGE. OTHERWISE ZONAL FLOW WILL CONTINUE OVER THE UPLAND SOUTH THRU TUE NIGHT...HEIGHTS THEN FALLING OVER THE MISSISSIPPI VALLEY WED WITH ANOTHER ARCTIC COLD FRONT DIVING INTO THAT AREA. THE HIGH SHIFTS EWD AND OFFSHORE WED IN RESPONSE...ALLOWING RETURN FLOW AND INCREASING THICKNESSES. OUR WEATHER WILL REMAIN DRY DURING THE PERIOD. MAX TEMPS TUE WILL BE A FEW DEGREES BELOW DAILY NORMALS...WITH NEAR NORMAL MINS WED MRNG. MAXES RISE TO A LITTLE ABOVE NORMAL FOR WED. DEWPOINTS WILL REMAIN ON THE LOW SIDE...PERHAPS MAKING FOR UNCOMFORTABLY DRY CONDITIONS. HOWEVER RH DOES NOT LOOK TO DROP BELOW CRITICAL LEVELS FOR FIRE WX. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 220 AM MONDAY...AT 00Z THURSDAY A COLD FRONT WILL BE APPROACHING FROM THE NORTHWEST AND A LOW WILL BE TRACKING EAST ACROSS THE GULF TOWARD FLORIDA. MOISTURE ASSOCIATED WITH THE FRONT IS RATHER SPARSE... ESPECIALLY ACCORDING TO THE ECMWF WHERE IT ONLY REACHES THE MTNS DRYING UP AS IT CROSSES INTO THE FOOTHILLS ON THE EAST SIDE THURSDAY. VARIOUS MODELS HAVE THE GULF LOW PASSING CLOSEST TO OUR AREA THURSDAY MORNING...WITH THE BEST FLUX OF MOISTURE ON THE ECMWF OVER PIEDMONT SECTIONS AROUND 12Z. HIGH PRESSURE BUILDS IN LATE THURSDAY FROM THE NORTHWEST BRINGING BREEZY CONDITIONS UNTIL THE CENTER OF THE HIGH PASSES JUST NORTH OF OUR AREA LATE THURSDAY NIGHT AND ON FRIDAY. THE HIGH SINKS SE TO BE ALIGNED FROM THE FLORIDA PANHANDLE TO THE CAROLINA COAST AT 00Z SATURDAY. THE COOL AIRMASS ASSOCIATED WITH THE HIGH WILL BE MODIFYING FROM A FEW DEGREES BELOW NORMAL ON FRIDAY TO BEING NEAR NORMAL HIGH TEMPS OVER THE WEEKEND. THE NEXT SHORTWAVE WILL BEGIN TO COME OVER THE EASTERN EDGE OF THE BROAD WESTERN UPPER RIDGE AROUND 00Z SUNDAY THEN DIG OVER THE MISSISSIPPI VALLEY BY LATE SUNDAY. THE RESULTING 500MB TROUGH WILL COVER MUCH IF NOT ALL OF THE TERRITORY EAST OF THE MISSISSIPPI RIVER AT 12Z MONDAY. LOWS WILL BE IN THE 30S OVER THE WEEKEND. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AT KCLT...ONE LAST ROUND OF MODERATE SHOWERS WILL CROSS THE AIRFIELD THROUGH 13Z BEFORE DRIER AIR BEGINS TO WRAP IN FROM THE SOUTHWEST. MVFR TEMPO IFR RESTRICTIONS ARE EXPECTED FOR THIS BRIEF PERIOD...WITH CIGS IMPROVING TO VFR BY LATE MORNING BEFORE SCATTERING. WINDS WILL TURN WESTERLY WITH FROPA 14Z AND THEN NW AND QUITE GUSTY AFTER 17Z. THE AFTN WILL BRING THE PERIOD OF DEEPEST MIXING AND COLD ADVECTION FLOW...WITH WIND GUSTS OF 30 TO 35 KT POSSIBLE AT TIMES...AND ISOLD GUSTS EVEN HIGHER. WINDS WILL ABATE THROUGH THE EVENING HOURS...WITH LITTLE MORE THAN PATCHY HIGH CLOUDS. AT KAVL...WINDS HAVED TURNED NW WITH FROPA...AND GUSTS WILL BEGIN AGAIN SOON. CIGS WILL BE MAINLY MVFR...BUT WITH BRIEF IFR POSSIBLE UNTIL THE BETTER MIXING STARTS. A FEW SNOW SHOWERS COULD APPROACH THE AIRFIELD DURING THE PEAK OF THE NW FLOW MOISTURE LATER THIS MORNING...BUT THE CHANCES ONLY WARRANT A VCSH MENTION AT PRESENT. GUSTS TO 35 KT WILL BE COMMON TODAY...AND SOME GUSTS ABOVE 40 KT CANNOT BE RULED OUT. THE GRADIENT SLOWLY RELAXES THIS EVENING. ELSEWHERE...CIGS WILL BE MAINLY MVFR AT THE FOOTHILL TAF SITES THIS MORNING BEFORE GRADUAL LIFTING AND SCOURING OCCURS IN THE NW FLOW FOLLOWING FROPA. NW FLOW GUSTS ABOVE 30 KT AREA LIKELY AT TIMES TODAY...AND PERHAPS NEAR 40 KT CLOSER TO KHKY THIS AFTN. WINDS WILL ABATE THIS EVENING...WITH CLEARING SKIES OVERNIGHT. OUTLOOK...VFR CONDITIONS ARE EXPECTED THROUGH MID WEEK. ANOTHER MOIST LOW PRESSURE SYSTEM/COLD FRONT MAY AFFECT THE REGION THU INTO FRI. CONFIDENCE TABLE... 11-17Z 17-23Z 23-05Z 05-06Z KCLT LOW 46% HIGH 100% HIGH 100% HIGH 100% KGSP LOW 53% HIGH 100% HIGH 100% HIGH 100% KAVL MED 64% MED 62% HIGH 100% MED 60% KHKY MED 71% HIGH 100% HIGH 100% HIGH 100% KGMU LOW 53% HIGH 100% HIGH 100% HIGH 100% KAND LOW 46% HIGH 100% HIGH 100% HIGH 100% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .GSP WATCHES/WARNINGS/ADVISORIES... GA...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR GAZ010. NC...WINTER WEATHER ADVISORY UNTIL 10 AM EST TUESDAY FOR NCZ033- 048>053-058-059-062-063. WIND ADVISORY UNTIL 7 PM EST THIS EVENING FOR NCZ035-064-065- 501>507-509. SC...NONE. && $$ SYNOPSIS...HG NEAR TERM...HG SHORT TERM...WIMBERLEY LONG TERM...DEO AVIATION...HG
AREA FORECAST DISCUSSION...UPDATED
NWS MEMPHIS TN
641 AM CST MON FEB 2 2015 .UPDATE... RECEIVED A REPORT OF LIGHT SNOW WITH A DUSTING ON CARS IN MCKENZIE TN IN NORTHWEST TN. UPDATED TO INCLUDE UNTIL MID-MORNING A SLIGHT CHANCE OF LIGHT SNOW FOR PORTIONS OF WEST TN...AND ISOLATED FLURRIES ELSEWHERE WITH SOME RADAR RETURNS BEING INDICATED. JCL && .DISCUSSION... /ISSUED 423 AM CST MON FEB 2 2015/ STRONG AND GUSTY NORTHWEST WINDS WERE FEEDING MUCH COLDER AIR INTO THE MIDSOUTH EARLY THIS MORNING. TEMPERATURES WERE IN THE 30S WITH WIND CHILL READINGS IN THE TEENS IN MANY LOCATIONS. LOW CLOUDS CONTINUED TO COVER THE REGION. OTHER THAN THE MUCH COLDER WEATHER TODAY...THE MAIN WEATHER STORY THIS WEEK WILL BE THE THREAT OF LIGHT SNOW ACCUMULATIONS WEDNESDAY NIGHT. FOR TODAY...A FEW SNOW FLURRIES MAY OCCUR ALONG THE TN RIVER VALLEY UNTIL ABOUT SUNRISE AS AN UPPER LEVEL TROUGH MOVES THROUGH THIS REGION. OTHERWISE...PRECIPITATION FREE WEATHER WILL OCCUR AS STRONG HIGH PRESSURE OVER THE PLAINS MOVE INTO THE MIDSOUTH AND UPPER LEVEL HEIGHTS INCREASE. TEMPERATURES WILL NOT CLIMB MUCH TODAY AND WILL REACH HIGHS ONLY A LITTLE BELOW FREEZING IN MANY SPOTS ALONG THE MO AND KY BORDERS. CLOUDS ARE FORECAST TO DECREASE THIS AFTERNOON... ALTHOUGH CONFIDENCE IS LOW WITH THE RAP MODEL KEEPING THE LOW CLOUDS OVER MUCH OF THE AREA THROUGH THIS AFTERNOON. A COLD NIGHT IS FORECAST TONIGHT WITH MOSTLY CLEAR TO PARTLY SKIES SKIES. LOW TEMPERATURES WILL RANGE FROM THE UPPER TEENS NEAR THE TN RIVER VALLEY OF WEST TN TO THE LOWER AND MIDDLE 20S ELSEWHERE. HIGH PRESSURE WILL MOVE SLOWLY TO THE EAST. FOLLOWING A COLD MORNING TUESDAY...TEMPERATURES WILL REBOUND IN THE AFTERNOON TO BETWEEN THE MIDDLE 40S AND LOWER 50S. HIGH PRESSURE WILL MOVE TO NEAR THE ATLANTIC COAST WITH INCREASING SOUTHWEST WINDS AND ABUNDANT SUNSHINE ACROSS THE MIDSOUTH. DRY WEATHER WILL CONTINUE TUESDAY NIGHT. LATEST MODELS INDICATE THAT THE DRY WEATHER WILL CONTINUE THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT... WILL BE WATCHING LOW PRESSURE MOVING TO OUR SOUTH AND AN ARCTIC COLD FRONT PUSHING INTO THE AREA FROM THE NORTH. STILL HAVE TO WORK OUT THE DETAILS AND TIMING OF THESE FEATURES...THE ECMWF AND GFS ARE STILL NOT IN THE BEST AGREEMENT. THE ARCTIC COLD FRONT WILL BE MOVING SOUTHWARD THROUGH MO WEDNESDAY...THE GFS IS FASTER THAN THE ECMWF. AROUND MIDDAY WEDNESDAY...THE GFS HAS THE FRONT MOVING INTO SOUTHERN MO WHILE THE ECMWF HAS THE FRONT THROUGH CENTRAL MO. MEANWHILE...AN UPPER LEVEL TROUGH WILL MOVE OFF THE TX COAST WITH LOW PRESSURE DEVELOPING OVER THE NORTHWEST GULF. KEPT IN A 20 PERCENT CHANCE OF RAIN FOR MUCH OF THE AREA WEDNESDAY AFTERNOON...ALTHOUGH IF THE FASTER GFS VERIFIES THEN RAIN CHANCES MAY NEED TO BE INCREASED ACROSS PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL INTO NORTHWEST TN. LATEST GFS AND ECMWF KEEP MOST IF NOT ALL OF THE RAIN WITH THE SOUTHERN LOW TO OUR SOUTH AS THE LOW TRACKS EASTWARD...BUT THE NAM IS A LITTLE FURTHER NORTH WITH THE RAIN GETTING CLOSE TO PORTIONS OF NORTH MS. WEDNESDAY NIGHT...STILL LOOKS INTERESTING WITH A THREAT OF LIGHT SNOW ACCUMULATIONS. THE ARCTIC COLD FRONT IS FORECAST TO CONTINUE PRESSING SOUTHWARD THROUGH THE REGION FOLLOWED BY MUCH COLDER AIR. AN UPPER LEVEL SHORT WAVE AND ASSOCIATED JET STREAK APPROACHING FROM THE NORTHWEST IS FORECAST TO PRODUCE LIFT OVER THE COLD AIR WITH RAIN CHANGING TO SNOW. THE GFS IS THE STRONGEST WITH THIS DISTURBANCE AND MORE OVER THE MIDSOUTH...PRODUCING SNOW AMOUNTS BETWEEN 1 AND 2 INCHES IN SOME LOCATIONS ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. THE ECMWF IS WEAKER AND A LITTLE FURTHER NORTH WITH THE DISTURBANCE AND INDICATES ABOUT 1/2 INCH OR LESS SNOW FOR MUCH OF THE MIDSOUTH. FOR NOW...TOOK MORE OF A COMPROMISE BETWEEN THE TWO. CONTINUED WORDING OF LIGHT SNOW ACCUMULATIONS IN THE HAZARDOUS WEATHER OUTLOOK AS IT IS TOO SOON TO PINPOINT ACCUMULATIONS. CONFIDENCE CONTINUES LOW WITH THE MODELS STILL NOT IN SYNC. BOTH THE ECMWF AND GFS INDICATE THAT ANY SNOW WILL MOVE QUICKLY OUT OF THE AREA EARLY THURSDAY MORNING WITH A RETURN TO SUNSHINE BY AFTERNOON. TEMPERATURES WILL BE COLD THURSDAY INTO FRIDAY MORNING AS MODIFIED ARCTIC AIR SETTLES OVER THE REGION. A WARMING TREND WILL OCCUR FRIDAY AFTERNOON INTO THE WEEKEND AS HIGH PRESSURE MOVES TO ALONG THE ATLANTIC COAST AND WIND TURN TO THE SOUTH ACROSS THE MIDSOUTH. THE NEXT CHANCE OF RAIN WILL BE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT APPROACHES AND MOVES INTO THE AREA FROM THE NORTHWEST. JCL && .AVIATION... SOME MVFR CONDITIONS STILL EXIST ACROSS THE REGION WITH JBR ALREADY SHOWING IMPROVEMENT ABOVE THAT THRESHOLD. WINDS HAVE CONTINUED TO BE STRONGER THAN GUIDANCE FROM THE NORTH...THEREFORE HAVE CONTINUED THAT TREND THROUGH THE MORNING. A GRADUAL DISSIPATION OF THE CLOUD DECK SHOULD OCCUR TODAY AS WINDS BACK AROUND TO THE NORTHEAST AND EVENTUALLY SOUTHEAST AFTER 00Z TUESDAY. VFR CONDITIONS WILL PREVAIL AT ALL SITES AFTER 18-21Z...EARLIER WEST...LATER AT EASTERN TERMINALS. TVT && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
518 AM CST MON FEB 2 2015 .UPDATE... UPDATED FOR 12Z AVIATION DISCUSSION BELOW... && .PREV DISCUSSION... /ISSUED 423 AM CST MON FEB 2 2015/ DISCUSSION... STRONG AND GUSTY NORTHWEST WINDS WERE FEEDING MUCH COLDER AIR INTO THE MIDSOUTH EARLY THIS MORNING. TEMPERATURES WERE IN THE 30S WITH WIND CHILL READINGS IN THE TEENS IN MANY LOCATIONS. LOW CLOUDS CONTINUED TO COVER THE REGION. OTHER THAN THE MUCH COLDER WEATHER TODAY...THE MAIN WEATHER STORY THIS WEEK WILL BE THE THREAT OF LIGHT SNOW ACCUMULATIONS WEDNESDAY NIGHT. FOR TODAY...A FEW SNOW FLURRIES MAY OCCUR ALONG THE TN RIVER VALLEY UNTIL ABOUT SUNRISE AS AN UPPER LEVEL TROUGH MOVES THROUGH THIS REGION. OTHERWISE...PRECIPITATION FREE WEATHER WILL OCCUR AS STRONG HIGH PRESSURE OVER THE PLAINS MOVE INTO THE MIDSOUTH AND UPPER LEVEL HEIGHTS INCREASE. TEMPERATURES WILL NOT CLIMB MUCH TODAY AND WILL REACH HIGHS ONLY A LITTLE BELOW FREEZING IN MANY SPOTS ALONG THE MO AND KY BORDERS. CLOUDS ARE FORECAST TO DECREASE THIS AFTERNOON... ALTHOUGH CONFIDENCE IS LOW WITH THE RAP MODEL KEEPING THE LOW CLOUDS OVER MUCH OF THE AREA THROUGH THIS AFTERNOON. A COLD NIGHT IS FORECAST TONIGHT WITH MOSTLY CLEAR TO PARTLY SKIES SKIES. LOW TEMPERATURES WILL RANGE FROM THE UPPER TEENS NEAR THE TN RIVER VALLEY OF WEST TN TO THE LOWER AND MIDDLE 20S ELSEWHERE. HIGH PRESSURE WILL MOVE SLOWLY TO THE EAST. FOLLOWING A COLD MORNING TUESDAY...TEMPERATURES WILL REBOUND IN THE AFTERNOON TO BETWEEN THE MIDDLE 40S AND LOWER 50S. HIGH PRESSURE WILL MOVE TO NEAR THE ATLANTIC COAST WITH INCREASING SOUTHWEST WINDS AND ABUNDANT SUNSHINE ACROSS THE MIDSOUTH. DRY WEATHER WILL CONTINUE TUESDAY NIGHT. LATEST MODELS INDICATE THAT THE DRY WEATHER WILL CONTINUE THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT... WILL BE WATCHING LOW PRESSURE MOVING TO OUR SOUTH AND AN ARCTIC COLD FRONT PUSHING INTO THE AREA FROM THE NORTH. STILL HAVE TO WORK OUT THE DETAILS AND TIMING OF THESE FEATURES...THE ECMWF AND GFS ARE STILL NOT IN THE BEST AGREEMENT. THE ARCTIC COLD FRONT WILL BE MOVING SOUTHWARD THROUGH MO WEDNESDAY...THE GFS IS FASTER THAN THE ECMWF. AROUND MIDDAY WEDNESDAY...THE GFS HAS THE FRONT MOVING INTO SOUTHERN MO WHILE THE ECMWF HAS THE FRONT THROUGH CENTRAL MO. MEANWHILE...AN UPPER LEVEL TROUGH WILL MOVE OFF THE TX COAST WITH LOW PRESSURE DEVELOPING OVER THE NORTHWEST GULF. KEPT IN A 20 PERCENT CHANCE OF RAIN FOR MUCH OF THE AREA WEDNESDAY AFTERNOON...ALTHOUGH IF THE FASTER GFS VERIFIES THEN RAIN CHANCES MAY NEED TO BE INCREASED ACROSS PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL INTO NORTHWEST TN. LATEST GFS AND ECMWF KEEP MOST IF NOT ALL OF THE RAIN WITH THE SOUTHERN LOW TO OUR SOUTH AS THE LOW TRACKS EASTWARD...BUT THE NAM IS A LITTLE FURTHER NORTH WITH THE RAIN GETTING CLOSE TO PORTIONS OF NORTH MS. WEDNESDAY NIGHT...STILL LOOKS INTERESTING WITH A THREAT OF LIGHT SNOW ACCUMULATIONS. THE ARCTIC COLD FRONT IS FORECAST TO CONTINUE PRESSING SOUTHWARD THROUGH THE REGION FOLLOWED BY MUCH COLDER AIR. AN UPPER LEVEL SHORT WAVE AND ASSOCIATED JET STREAK APPROACHING FROM THE NORTHWEST IS FORECAST TO PRODUCE LIFT OVER THE COLD AIR WITH RAIN CHANGING TO SNOW. THE GFS IS THE STRONGEST WITH THIS DISTURBANCE AND MORE OVER THE MIDSOUTH...PRODUCING SNOW AMOUNTS BETWEEN 1 AND 2 INCHES IN SOME LOCATIONS ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. THE ECMWF IS WEAKER AND A LITTLE FURTHER NORTH WITH THE DISTURBANCE AND INDICATES ABOUT 1/2 INCH OR LESS SNOW FOR MUCH OF THE MIDSOUTH. FOR NOW...TOOK MORE OF A COMPROMISE BETWEEN THE TWO. CONTINUED WORDING OF LIGHT SNOW ACCUMULATIONS IN THE HAZARDOUS WEATHER OUTLOOK AS IT IS TOO SOON TO PINPOINT ACCUMULATIONS. CONFIDENCE CONTINUES LOW WITH THE MODELS STILL NOT IN SYNC. BOTH THE ECMWF AND GFS INDICATE THAT ANY SNOW WILL MOVE QUICKLY OUT OF THE AREA EARLY THURSDAY MORNING WITH A RETURN TO SUNSHINE BY AFTERNOON. TEMPERATURES WILL BE COLD THURSDAY INTO FRIDAY MORNING AS MODIFIED ARCTIC AIR SETTLES OVER THE REGION. A WARMING TREND WILL OCCUR FRIDAY AFTERNOON INTO THE WEEKEND AS HIGH PRESSURE MOVES TO ALONG THE ATLANTIC COAST AND WIND TURN TO THE SOUTH ACROSS THE MIDSOUTH. THE NEXT CHANCE OF RAIN WILL BE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT APPROACHES AND MOVES INTO THE AREA FROM THE NORTHWEST. JCL .AVIATION... SOME MVFR CONDITIONS STILL EXIST ACROSS THE REGION WITH JBR ALREADY SHOWING IMPROVEMENT ABOVE THAT THRESHHOLD. WINDS HAVE CONTINUED TO BE STRONGER THAN GUIDANCE FROM THE NORTH...THEREFORE HAVE CONTINUED THAT TREND THROUGH THE MORNING. A GRADUAL DISSIPATION OF THE CLOUD DECK SHOULD OCCUR TODAY AS WINDS BACK AROUND TO THE NORTHEAST AND EVENTUALLY SOUTHEAST AFTER 00Z TUESDAY. VFR CONDITIONS WILL PREVAIL AT ALL SITES AFTER 18-21Z...EARLIER WEST...LATER AT EASTERN TERMINALS. TVT && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
423 AM CST MON FEB 2 2015 .DISCUSSION... STRONG AND GUSTY NORTHWEST WINDS WERE FEEDING MUCH COLDER AIR INTO THE MIDSOUTH EARLY THIS MORNING. TEMPERATURES WERE IN THE 30S WITH WIND CHILL READINGS IN THE TEENS IN MANY LOCATIONS. LOW CLOUDS CONTINUED TO COVER THE REGION. OTHER THAN THE MUCH COLDER WEATHER TODAY...THE MAIN WEATHER STORY THIS WEEK WILL BE THE THREAT OF LIGHT SNOW ACCUMULATIONS WEDNESDAY NIGHT. FOR TODAY...A FEW SNOW FLURRIES MAY OCCUR ALONG THE TN RIVER VALLEY UNTIL ABOUT SUNRISE AS AN UPPER LEVEL TROUGH MOVES THROUGH THIS REGION. OTHERWISE...PRECIPITATION FREE WEATHER WILL OCCUR AS STRONG HIGH PRESSURE OVER THE PLAINS MOVE INTO THE MIDSOUTH AND UPPER LEVEL HEIGHTS INCREASE. TEMPERATURES WILL NOT CLIMB MUCH TODAY AND WILL REACH HIGHS ONLY A LITTLE BELOW FREEZING IN MANY SPOTS ALONG THE MO AND KY BORDERS. CLOUDS ARE FORECAST TO DECREASE THIS AFTERNOON... ALTHOUGH CONFIDENCE IS LOW WITH THE RAP MODEL KEEPING THE LOW CLOUDS OVER MUCH OF THE AREA THROUGH THIS AFTERNOON. A COLD NIGHT IS FORECAST TONIGHT WITH MOSTLY CLEAR TO PARTLY SKIES SKIES. LOW TEMPERATURES WILL RANGE FROM THE UPPER TEENS NEAR THE TN RIVER VALLEY OF WEST TN TO THE LOWER AND MIDDLE 20S ELSEWHERE. HIGH PRESSURE WILL MOVE SLOWLY TO THE EAST. FOLLOWING A COLD MORNING TUESDAY...TEMPERATURES WILL REBOUND IN THE AFTERNOON TO BETWEEN THE MIDDLE 40S AND LOWER 50S. HIGH PRESSURE WILL MOVE TO NEAR THE ATLANTIC COAST WITH INCREASING SOUTHWEST WINDS AND ABUNDANT SUNSHINE ACROSS THE MIDSOUTH. DRY WEATHER WILL CONTINUE TUESDAY NIGHT. LATEST MODELS INDICATE THAT THE DRY WEATHER WILL CONTINUE THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT... WILL BE WATCHING LOW PRESSURE MOVING TO OUR SOUTH AND AN ARCTIC COLD FRONT PUSHING INTO THE AREA FROM THE NORTH. STILL HAVE TO WORK OUT THE DETAILS AND TIMING OF THESE FEATURES...THE ECMWF AND GFS ARE STILL NOT IN THE BEST AGREEMENT. THE ARCTIC COLD FRONT WILL BE MOVING SOUTHWARD THROUGH MO WEDNESDAY...THE GFS IS FASTER THAN THE ECMWF. AROUND MIDDAY WEDNESDAY...THE GFS HAS THE FRONT MOVING INTO SOUTHERN MO WHILE THE ECMWF HAS THE FRONT THROUGH CENTRAL MO. MEANWHILE...AN UPPER LEVEL TROUGH WILL MOVE OFF THE TX COAST WITH LOW PRESSURE DEVELOPING OVER THE NORTHWEST GULF. KEPT IN A 20 PERCENT CHANCE OF RAIN FOR MUCH OF THE AREA WEDNESDAY AFTERNOON...ALTHOUGH IF THE FASTER GFS VERIFIES THEN RAIN CHANCES MAY NEED TO BE INCREASED ACROSS PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL INTO NORTHWEST TN. LATEST GFS AND ECMWF KEEP MOST IF NOT ALL OF THE RAIN WITH THE SOUTHERN LOW TO OUR SOUTH AS THE LOW TRACKS EASTWARD...BUT THE NAM IS A LITTLE FURTHER NORTH WITH THE RAIN GETTING CLOSE TO PORTIONS OF NORTH MS. WEDNESDAY NIGHT...STILL LOOKS INTERESTING WITH A THREAT OF LIGHT SNOW ACCUMULATIONS. THE ARCTIC COLD FRONT IS FORECAST TO CONTINUE PRESSING SOUTHWARD THROUGH THE REGION FOLLOWED BY MUCH COLDER AIR. AN UPPER LEVEL SHORT WAVE AND ASSOCIATED JET STREAK APPROACHING FROM THE NORTHWEST IS FORECAST TO PRODUCE LIFT OVER THE COLD AIR WITH RAIN CHANGING TO SNOW. THE GFS IS THE STRONGEST WITH THIS DISTURBANCE AND MORE OVER THE MIDSOUTH...PRODUCING SNOW AMOUNTS BETWEEN 1 AND 2 INCHES IN SOME LOCATIONS ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. THE ECMWF IS WEAKER AND A LITTLE FURTHER NORTH WITH THE DISTURBANCE AND INDICATES ABOUT 1/2 INCH OR LESS SNOW FOR MUCH OF THE MIDSOUTH. FOR NOW...TOOK MORE OF A COMPROMISE BETWEEN THE TWO. CONTINUED WORDING OF LIGHT SNOW ACCUMULATIONS IN THE HAZARDOUS WEATHER OUTLOOK AS IT IS TOO SOON TO PINPOINT ACCUMULATIONS. CONFIDENCE CONTINUES LOW WITH THE MODELS STILL NOT IN SYNC. BOTH THE ECMWF AND GFS INDICATE THAT ANY SNOW WILL MOVE QUICKLY OUT OF THE AREA EARLY THURSDAY MORNING WITH A RETURN TO SUNSHINE BY AFTERNOON. TEMPERATURES WILL BE COLD THURSDAY INTO FRIDAY MORNING AS MODIFIED ARCTIC AIR SETTLES OVER THE REGION. A WARMING TREND WILL OCCUR FRIDAY AFTERNOON INTO THE WEEKEND AS HIGH PRESSURE MOVES TO ALONG THE ATLANTIC COAST AND WIND TURN TO THE SOUTH ACROSS THE MIDSOUTH. THE NEXT CHANCE OF RAIN WILL BE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT APPROACHES AND MOVES INTO THE AREA FROM THE NORTHWEST. JCL && .AVIATION... 06Z TAF CYCLE LOW CLOUDS WILL RESULT IN MVFR CONDITIONS TONIGHT WITH VFR CONDITIONS RETURNING AREA WIDE EARLY TOMORROW. WINDS WILL BE STRONG AND GUSTY TONIGHT...FROM THE NORTH. WIND SPEEDS WILL DECREASE TO AROUND 5KTS BY MIDDAY TOMORROW BUT REMAIN NORTHERLY. && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION...UPDATED
NWS AMARILLO TX
538 AM CST MON FEB 2 2015 .AVIATION... STRATOCUMULUS CEILINGS CURRENTLY SEEN IN SATELLITE IMAGERY ACROSS WESTERN 2/3 OF TEXAS PANHANDLE EXPECTED TO REMAIN IN VFR RANGE BEFORE SCATTERING OUT AROUND 15Z. SOUTH SOUTHWEST SURFACE WINDS EXPECTED TO GUST TO AROUND 25 KT FROM MID-MORNING TO MID-AFTERNOON TODAY. GUSTS EXPECTED TO CEASE AROUND 22Z OR 23Z...WITH LIGHT SURFACE WINDS VEERING TO WESTERLY BEFORE SUNRISE TUESDAY. NO OVERNIGHT LOW CLOUDS OR VISIBILITY RESTRICTIONS EXPECTED DURING THE LATER HOURS OF THIS FORECAST. VFR FORECAST CONTINUES NEXT 24 HOURS. COCKRELL && .PREV DISCUSSION... /ISSUED 318 AM CST MON FEB 2 2015/ DISCUSSION... EARLY THIS MORNING 11-3.9 IR AND SURFACE OBS SHOWED PERSISTENT STRATUS ACROSS MAINLY THE WESTERN HALF OF THE AREA. SURFACE HIGH IN THE WAKE OF DEPARTING SHORTWAVE NOW OVER THE MID/LOWER MISSISSIPPI VALUE WAS MOVING SOUTHEASTWARD AND SOUTHERLY SURFACE WINDS HAVE INCREASED IN THE WESTERN PORTION OF THE PANHANDLES. WATER VAPOR AND 500 MB RAP ANALYSIS LOOP SHOW PACIFIC MOISTURE STREAMING EASTWARD IN INCREASING MOMENTUM ACROSS THE WESTERN CONUS. AS CROSS MOUNTAIN FLOW STRENGTHENS TODAY SO WILL LEE SIDE SURFACE TROUGH. PRESSURE GRADIENT BETWEEN STRENGTHENING LEE TROUGH AND DEPARTING SURFACE HIGH WILL RESULT IN BREEZY SOUTHWESTERLY WINDS THROUGH AFTERNOON. RISING HEIGHTS AND WARMING ALOFT IN ADDITION TO FULL SUN...MIXING...AND AT LEAST SOMEWHAT OF A DOWNSLOPE COMPONENT TO SURFACE WINDS WILL RESULT IN A WARMING TREND TODAY AND TOMORROW. ATTENTION THEN SHIFTS TO A COLD FRONT THAT WILL PASS THROUGH ON WEDNESDAY. GIVEN TRAJECTORIES FAVORING ONLY A MODESTLY COLD AIR MASS...AM LESS CONCERNED ABOUT SIGNIFICANT FRONTAL TIMING ISSUES THAT ARE TYPICAL OF SHALLOW VERY COLD ARCTIC FRONTS. HAVE THE FRONT MOVING THROUGH FASTER THAN MODEL CONSENSUS BUT NOT QUITE AS FAST AS THE GFS AS THE GFS/GEFS MEAN ARE AN OUTLIER WITH HOW FAST NORTHERN STREAM SHORTWAVE (THAT IS FORCING THIS COLD SURGE) MOVES THROUGH THE MIDWEST COMPARED TO OTHER MODEL GUIDANCE. THIS CHOSEN TIMING IS FAIRLY CONSISTENT WITH THE PREVIOUS FORECAST. THE TIMING THAT WE HAVE AT THIS POINT NECESSITATED A NON-CLIMO DIURNAL CURVE WHICH WAS CONSTRUCTED USING HOURLY TEMPERATURE GRIDS. THIS RESULTS IN A TIGHT GRADIENT IN THE HIGH TEMPERATURE GRID FOR WEDNESDAY. IN FACT...IF THE SLOWER FRONTAL TIMING OCCURS...THE WEST AND ESPECIALLY SOUTHWEST TEXAS PANHANDLE MAY SIGNIFICANTLY EXCEED NORMAL HIGH TEMPERATURES WEDNESDAY AFTERNOON. ADJUSTMENTS ON TEMPERATURES WILL NEED TO BE MADE IN SUBSEQUENT FORECASTS DEPENDING ON FRONTAL TIMING. OTHER SENSIBLE WEATHER CHANGES INCLUDE A GOOD CHANCE OF POST-FRONTAL LOW STRATUS LATE WEDNESDAY LASTING INTO THURSDAY MORNING. THE BEST MOISTURE AND DEEPEST LIFT WILL REMAIN NORTHEAST OF THE AREA AND CHANCES OF MEASURABLE PRECIPITATION LOOK TO BE CONFINED TO PORTIONS OF CENTRAL KANSAS ON WEDNESDAY. KEPT MENTION OF SNOW FLURRIES WITH NON- MEASURABLE LIQUID AMOUNTS IN THE FAR NORTHEAST GIVEN A MODESTLY DEEP SATURATED LAYER IN THE LOW LEVELS BUT CONFIDENCE IN EVEN TRACE AMOUNTS IS NOT PARTICULARLY HIGH. FROM LATE WEEK THROUGH THE WEEKEND THE LARGE SCALE PATTERN FEATURES BUILDING LOW AMPLITUDE RIDGING RESULTING IN ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. FRIDAY AND SATURDAY LOOK TO BE THE WARMEST DAYS WITH MANY LOCATIONS REACHING INTO THE 70S. A PASSING SHORTWAVE TROUGH MAY FORCE A MODEST COOL SURGE INTO THE AREA BY SUNDAY BUT AT THIS POINT IT LOOKS LIKE TEMPERATURES WILL STILL BE ABLE TO RISE TO ABOVE NORMAL LEVELS. BRB && .PRELIMINARY POINT TEMPS/POPS... AMARILLO TX 55 31 65 34 59 / 0 0 0 0 5 BEAVER OK 51 24 68 30 37 / 0 0 0 0 10 BOISE CITY OK 60 30 66 35 44 / 0 0 0 0 5 BORGER TX 56 32 65 37 51 / 0 0 0 0 5 BOYS RANCH TX 59 27 66 31 51 / 0 0 0 0 5 CANYON TX 56 29 66 33 62 / 0 0 0 0 5 CLARENDON TX 50 30 62 35 56 / 0 0 0 0 5 DALHART TX 58 31 64 34 59 / 0 0 0 0 5 GUYMON OK 56 28 69 33 39 / 0 0 0 0 10 HEREFORD TX 59 28 65 32 62 / 0 0 0 0 5 LIPSCOMB TX 48 29 66 35 41 / 0 0 0 0 10 PAMPA TX 50 30 66 35 47 / 0 0 0 0 5 SHAMROCK TX 45 26 60 35 49 / 0 0 0 0 10 WELLINGTON TX 47 30 61 37 50 / 0 0 0 0 10 && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 03/17
AREA FORECAST DISCUSSION
NWS EL PASO TX/SANTA TERESA NM
326 AM MST MON FEB 2 2015 .SYNOPSIS... HIGH PRESSURE ALOFT BUILDING IN OVER THE DESERT SOUTHWEST WILL KEEP A DRY WEST TO NORTHWEST FLOW OVER THE BORDERLAND FOR MOST OF THIS WEEK. EXPECT VERY FEW CLOUDS...AND WITH THE BOUNTIFUL SUNSHINE... HIGH TEMPERATURES WILL SURGE TO WELL ABOVE NORMAL. THE WARMEST DAYS OF THE BUNCH LOOK TO BE THIS WEEKEND...WITH LOWLAND TEMPERATURES REACHING OR EXCEEDING 70 DEGREES. && .DISCUSSION... A VERY QUIET WEEK...ESPECIALLY AFTER THE PAST COUPLE OF WEEKS...IS SHAPING UP FOR US AS HIGH PRESSURE RIDGE ALOFT BUILDS FROM THE EASTERN PACIFIC OVER THE DESERT SOUTHWEST AND MAINTAINS ITSELF FOR MOST OF THE WEEK. IN THE SHORT TERM STILL A BIT CONCERNED ABOUT DENSE FOG THIS MORNING. SATELLITE FOG PRODUCT SHOWS THE STRATUS OF THE FAR EASTERN CWA REMAINING DAMMED NEAR THE HIGHER TERRAIN. CLOUDS NOT MOVING WEST MUCH BEHIND THE WEAK BACK DOOR FRONT THAT EXTENDS NORTH-SOUTH THROUGH THE CENTRAL CWA. OF MORE CONCERN ARE THE SOUTHERN NEW MEXICO LOWLAND ZONES. SATELLITE SHOWING DECENT AREA OF STRATUS FORMING WEST OF I-25 AND NORTH OF I-10 BUT THE FEW OBS IN THIS DO NOT SHOW ANY FOG...JUST LOWER DECK OF CLOUDS. HRRR CONTINUES TO SHOW GOOD POTENTIAL FOR FOG DEVELOPMENT WEST OF EL PASO WITH ZERO DEGREE DEWPOINT DEPRESSIONS AND LIGHT WINDS. TO THE EAST... DEPRESSIONS ARE TOO HIGH AND WINDS A BIT TOO MUCH YET. WILL LET GRIDS/ZONE PACKAGE SPELL OUT PATCHY FOG AND FORGO ANY ADVISORIES FOR NOW. OTHERWISE...VERY LITTLE WEATHER TO SPEAK OF. WEAK BACK DOOR FRONT PUSHES IN WED NIGHT AS SMALL UPPER TROUGH SLIDES DOWN THE FRONT SIDE OF THE UPPER RIDGE AND INTO THE SOUTHERN PLAINS. MODEST COOLING THURSDAY WITH THIS FRONT. SATURDAY NIGHT SOME COOLER AIR FILTERS DOWN FROM THE SOUTHERN ROCKIES FOR A BIT OF COOLING ON SUNDAY. OTHER THAN THAT...TEMPERATURES WILL BE ON THE UPSWING ALL WEEK...WITH HIGHS 6-12 DEGREES ABOVE NORMAL. LOWLAND HIGHS BY FRIDAY AND BEYOND MAY REACH OR EXCEED 70 DEGREES. && .AVIATION...VALID 02/12Z-03/12Z... MAINLY VFR CONDS THROUGH PERIOD. PATCHY AREAS OF FOG POSSIBLE OVER THE LOWLANDS WEST OF EL PASO WITH VSBYS BTWN 1/2SM AND 3SM BKN008 TIL 17Z. FURTHER EAST...BKN/OVC060 TOPS 090...WITH A FEW AREAS OF 1SM BR...MAINLY ALONG AND EAST OF A LINE FROM ALAMOGORDO TO CORNUDAS. THESE CLOUDS SHOULD DISSIPATE AFTER 18Z. && .FIRE WEATHER... DRY AND WARM WEEK AHEAD AS UPPER RIDGE DOMINATES THE WEATHER PATTERN. SOME LOW CLOUDS AND FOG ALONG EAST SLOPES OF THE SACRAMENTO MOUNTAINS AND OVER THE OTERO MESA/GUADALUPE MOUNTAINS SHOULD DISSIPATE AFTER 18Z. VERY FEW CLOUDS EXPECTED THE REST OF THIS WEEK. TEMPERATURES WILL CONTINUE WARMING TREND WITH HIGHS MOSTLY 6 TO 12 DEGREES ABOVE NORMAL. MIN RH`S WILL REMAIN IN THE 40S TODAY BUT THEN FALL INTO THE 30S FOR THE REST OF THE WEEK. && .PRELIMINARY POINT TEMPS/POPS... EL PASO 60 37 65 41 68 / 0 0 0 0 0 SIERRA BLANCA 60 37 63 38 66 / 0 0 0 0 0 LAS CRUCES 59 35 63 38 67 / 0 0 0 0 0 ALAMOGORDO 57 32 61 37 64 / 0 0 0 0 0 CLOUDCROFT 45 25 49 31 51 / 0 0 0 0 0 TRUTH OR CONSEQUENCES 57 36 61 37 65 / 0 0 0 0 0 SILVER CITY 58 34 62 37 64 / 0 0 0 0 0 DEMING 62 33 63 35 68 / 0 0 0 0 0 LORDSBURG 62 33 62 36 67 / 0 0 0 0 0 WEST EL PASO METRO 61 39 66 41 68 / 0 0 0 0 0 DELL CITY 57 32 63 34 68 / 0 0 0 0 0 FORT HANCOCK 62 37 63 39 67 / 0 0 0 0 0 LOMA LINDA 56 35 59 40 63 / 0 0 0 0 0 FABENS 59 35 64 38 67 / 0 0 0 0 0 SANTA TERESA 59 34 64 39 67 / 0 0 0 0 0 WHITE SANDS HQ 59 36 64 41 67 / 0 0 0 0 0 JORNADA RANGE 58 31 61 35 65 / 0 0 0 0 0 HATCH 59 33 67 35 69 / 0 0 0 0 0 COLUMBUS 62 35 63 38 67 / 0 0 0 0 0 OROGRANDE 58 36 64 40 65 / 0 0 0 0 0 MAYHILL 55 31 59 35 61 / 0 0 0 0 0 MESCALERO 50 26 54 32 57 / 0 0 0 0 0 TIMBERON 52 31 55 34 59 / 0 0 0 0 0 WINSTON 54 32 58 34 61 / 0 0 0 0 0 HILLSBORO 57 38 59 40 65 / 0 0 0 0 0 SPACEPORT 59 33 63 37 66 / 0 0 0 0 0 LAKE ROBERTS 57 33 61 34 62 / 0 0 0 0 0 HURLEY 56 33 59 36 64 / 0 0 0 0 0 CLIFF 59 28 62 29 65 / 0 0 0 0 0 MULE CREEK 58 25 60 28 64 / 0 0 0 0 0 FAYWOOD 55 36 59 39 65 / 0 0 0 0 0 ANIMAS 65 32 65 37 68 / 0 0 0 0 0 HACHITA 65 31 65 35 68 / 0 0 0 0 0 ANTELOPE WELLS 65 30 64 35 69 / 0 0 0 0 0 CLOVERDALE 63 33 63 38 66 / 0 0 0 0 0 && .EPZ WATCHES/WARNINGS/ADVISORIES... NM...NONE. TX...NONE. && $$ 17 HEFNER
AREA FORECAST DISCUSSION
NWS PUEBLO CO
1042 AM MST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 533 AM MST MON FEB 2 2015 ...WAVES OF SNOW FOR THE CENTRAL MOUNTAINS...NICE REBOUND IN TEMPERATURES ELSEWHERE... NEXT SHORTWAVE/ASSOC UPPER JET IS MOVING ACROSS NRN CO EARLY THIS MORNING. HAVE SEEN SOME GUSTY WINDS REPORTED AT MTN TOP LEVEL AND ALONG THE LOWER EASTERN SLOPES OF THE SAWATCH RANGE...SANGRES...AND THE PIKES PEAK AND THE RAMPART RANGE. PEAK GUST SO FAR WAS 62 KTS AT 7BM (COTTONWOOD PASS)...BUT WOULDN`T BE SURPRISED TO SEE A FEW STRONGER GUSTS ACROSS THE HIGHER PEAKS BEFORE MORNING. THESE STRONGER GUSTS SHOULD REMAIN FAIRLY LOCALIZED...AS 7BM HAS SINCE DROPPED BACK TO 45 KTS...BUT IT WILL REMAIN WINDY NONE-THE-LESS. HAVE BOOSTED WIND GUSTS IN MORNING GRIDS. CENTRAL MOUNTAINS WILL SEE SNOW CONTINUE THIS MORNING ASSOC WITH THIS WAVE EMBEDDED WITHIN OROGRAPHICALLY FAVORED NORTHWEST FLOW. HIGHER MTS COULD PICK UP AN INCH OR TWO THIS MORNING. MEANWHILE...LOW CLOUDS ACROSS EL PASO COUNTY WILL HANG IN EARLY THIS MORNING DUE TO WEAK SOUTHERLY UPSLOPE WINDS. STARTING TO SEE SOUTHWEST WINDS INCREASE ACROSS THE RAMPART RANGE THOUGH...AND LATEST HRRR SHOWS LOW LEVEL CLOUDS ERODING EAST OF KCOS AROUND 13Z. OTHERWISE...MID/HIGH LEVEL WAVE CLOUDINESS ALONG THE LEE OF THE SE MTS WILL SHIFT EASTWARD THIS MORNING WITH MOSTLY SUNNY SKIES EXPECTED BY AFTERNOON BEHIND THE DEPARTING UPPER WAVE. SNOW WILL ALSO DECREASE ACROSS THE CENTRAL MOUNTAINS AS DRIER AIR SPREADS IN BEHIND THE SYSTEM. MEANWHILE...LEE TROF SHOULD BRING REBOUNDING TEMPERATURES TO THE SOUTHEAST PLAINS...WITH HIGHS TODAY BACK INTO THE 50S. FAVORED AREAS ALONG THE LEE OF THE SE MTS WILL SEE SOME LOCAL GUSTS TO 25-30 MPH...MAINLY THIS MORNING. TONIGHT...LEE TROFFING SHOULD KEEP TEMPERATURES ON THE WARM SIDE...ESPECIALLY TO THE LEE OF THE SE MTS. NEXT WAVE MOVES IN LATE SPREADING ANOTHER ROUND OF SNOW INTO THE CENTRAL MOUNTAINS. ELSEWHERE WILL SEE SOME PASSING WAVE CLOUDINESS AT TIMES. WINDS WILL INCREASE AGAIN ACROSS THE HIGHER PEAKS TOWARDS DAWN TUESDAY. -KT .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 533 AM MST MON FEB 2 2015 RECENT LONGER TERM COMPUTER SIMULATIONS ARE CONTINUING TO REMAIN IN RELATIVELY CLOSE AGREEMENT PROJECTING GENERALLY DRY CONDITIONS(OUTSIDE OF THE CENTRAL MOUNTAINS AT TIMES) AND BASICALLY MILD TO WARM CONDITIONS(OUTSIDE OF WEDNESDAY) FROM TUESDAY INTO THE WEEKEND...THANKS TO A NORTHWESTERLY TO UPPER RIDGING PATTERN DEVELOPING OVER THE FORECAST DISTRICT. OVER PORTIONS OF THE CENTRAL MOUNTAINS...ACCUMULATING SNOW IN THE ONE TO FIVE INCH RANGE DURING ANY 12 HOUR PERIOD...IS ANTICIPATED FROM TUESDAY INTO WEDNESDAY NIGHT...ALTHOUGH RECENT 06Z/2ND COMPUTER SIMULATIONS HAVE STARTED TO TREND LOWER WITH POTENTIAL SNOW AMOUNTS. WFO PUEBLO WILL CONTINUE TO MONITOR REAL-TIME DATA AS WELL AS COMPUTER SIMULATIONS FOR LATER SNOW TRENDS AND POSSIBLE WINTER WEATHER HIGHLIGHTS. ELSEWHERE. AT THE SURFACE...THE SOUTHEASTERN COLORADO PLAINS LEE-SIDE TROUGHING FROM TUESDAY INTO TUESDAY NIGHT WILL BE REPLACED BY A COOLER AND SOMEWHAT MOIST NORTHEASTERLY TO EASTERLY SURFACE SURGE(DRIVEN BY A 1035 MB SURFACE HIGH LOCATED OVER EASTERN NEBRASKA AT 00Z THURSDAY) FROM WEDNESDAY MORNING INTO WEDNESDAY EVENING IN CONJUNCTION WITH A PASSING UPPER DISTURBANCE(GENERALLY FOCUSED TO THE NORTH AND EAST OF THE CWFA)...WHICH WILL ALLOW FOR THE COOL AND CLOUDY CONDITIONS...ESPECIALLY OVER EASTERN SECTIONS DURING THIS TIME-FRAME. IN ADDITION...SHOWERS WILL BE POSSIBLE...PRIMARILY OVER NORTHERN AND EASTERN SECTIONS OF THE FORECAST DISTRICT FROM WEDNESDAY INTO WEDNESDAY NIGHT. THEN THE COMBINATION OF VARYING DEGREES OF UPPER RIDGING AND EASTERN COLORADO SURFACE LEE-SIDE TROUGHING WILL ALLOW GENERALLY DRY AND ABOVE SEASONAL TEMPERATURE(ESPECIALLY EASTERN SECTIONS) FROM THURSDAY INTO THE WEEKEND. AT THIS TIME...IT APPEARS THAT THE WARMEST CONDITIONS OF THE LONGER TERM WILL BE NOTED FRIDAY AND SATURDAY WHILE COOLEST READING OCCUR WEDNESDAY. FINALLY...THE HIGHEST POTENTIAL FOR GUSTY WINDS ARE ANTICIPATED TUESDAY NIGHT AND THEN AGAIN THURSDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1024 AM MST MON FEB 2 2015 VFR CONDITIONS WILL CONTINUE TODAY AND TONIGHT AT KALS...KCOS AND KPUB. OVER THE MOUNTAINS...PERIODS OF STRONG WEST WINDS WILL BE POSSIBLE OVER MOST HIGHER PEAKS INTO THIS AFTERNOON...WITH GUSTS OF 30-40 KTS. ACROSS THE CENTRAL MOUNTAINS...SNOW SHOWERS WILL PRODUCE PERIODS OF IFR CONDITIONS THIS AFTERNOON...THEN AGAIN LATE TONIGHT AFTER 09Z. && .PUB WATCHES/WARNINGS/ADVISORIES... NONE. && $$ AVIATION...PETERSEN
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
254 PM EST MON FEB 2 2015 .UPDATE... THE LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 254 AM EST MON FEB 2 2015 LIGHT SNOW BANDS ON THE BACK SIDE OF RETREATING LOW WILL PERSIST THIS MORNING ACROSS CENTRAL INDIANA...BUT HIGH PRESSURE WILL STRENGTHEN BY THIS AFTERNOON. AFTER CHILLY TEMPERATURES TODAY...THERE WILL BE A WARM UP BY TOMORROW. HOWEVER...A COLD FRONT PROGGED FOR TUESDAY NIGHT WILL BRING LIGHT SNOW SHOWERS THROUGH WEDNESDAY NIGHT. COLDER BUT DRY WEATHER CAN BE EXPECTED AT THE END OF THE WEEK AS HIGH PRESSURE RE-ESTABLISHES ITSELF OVER THE AREA. FURTHER OUT...THE NEXT SYSTEM IS SET TO MOVE THROUGH THE REGION NEXT WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1008 AM EST MON FEB 2 2015 RADAR MOSAIC AT 10 AM SHOWS SCATTERED FLURRIES AND A SMALL BAND OF LIGHT SNOW SHOWERS MOVING SOUTH SOUTHEAST THROUGH CENTRAL INDIANA. SHORT TERM MODELS ARE NOT DOING A GREAT JOB RESOLVING THESE PROBABLY DUE TO THEIR RELATIVELY LOCAL NATURE. THUS EVEN THOUGH HRRR AND RAP ARE NOT SHOWING MUCH OF ANYTHING GOING LATE THIS MORNING AND INTO THE AFTERNOON...BASED ON SATELLITE OBSERVATIONS...WIND DIRECTIONS AND TRENDS HAVE ADDED ISOLATED SNOW SHOWERS WITH SCATTERED FLURRIES INTO EARLY AFTERNOON FOR MOST OF THE AREA. ALSO KEPT POPS IN THE LATER AFTERNOON ALIGNED WITH POSSIBLE LAKE EFFECT BAND MIGRATING EASTWARD ACROSS THE NORTHERN COUNTIES. ALSO ADDED SOME FLURRIES ACROSS THE NORTHERN HALF OR SO OF THE AREA THROUGH THE AFTERNOON WITH THE NORTHERLY FLOW OFF THE LAKE AND CYCLONIC FLOW EXITING THE AREA. INCREASED CLOUD COVER INTO THE MID AFTERNOON ALSO BASED ON SATELLITE TRENDS AND ENHANCED LAKE EFFECT CLOUDS. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 254 AM EST MON FEB 2 2015 THE FOCUS OF THE SHORT TERM PERIOD IS A COLD FRONT PROGGED FOR TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. FIRST...STRONG SUBSIDENCE OVER CENTRAL INDIANA WILL RESULT IN DRY CONDITIONS FROM TONIGHT THROUGH TOMORROW. WEAK RADIATIONAL COOLING TONIGHT WILL ALLOW TEMPS TO DIP INTO THE SINGLE DIGITS AND TEENS...THUS RESULTING IN WIND CHILLS BELOW ZERO OVER THE NORTHERN HALF OF THE FORECAST AREA. FOCUS THEN TURNS TO THE IMPENDING COLD FRONT PASSAGE ON TUESDAY NIGHT. LIGHT SNOW SHOULD START SPREADING ACROSS THE AREA FROM NORTH TO SOUTH ON TUESDAY NIGHT. THE BEST DYNAMICS WITH FRONT WILL BE ON WEDNESDAY AND WEDNESDAY NIGHT. AS OF NOW...WILL GO WITH ALL SNOW FORECAST DUE TO THE COLD AIR ALOFT. HOWEVER...CONCERNED WITH TEMPERATURES TOPPING OFF IN THE LOW 40S ACROSS THE SOUTHERN COUNTIES ON WEDNESDAY...POSSIBLY CREATING MORE OF A RAIN/SNOW MIX DURING THE DAY. ANY LINGERING PRECIP ON WEDNESDAY NIGHT SHOULD DEFINITELY BE IN THE FORM OF SNOW THOUGH AS TEMPERATURES PLUMMET INTO THE SINGLE DIGITS AND TEENS BEHIND COLD FRONT. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... ISSUED AT 251 PM EST MON FEB 2 2015 THE FIRST FEW DAYS OF THE EXTENDED WILL BE DRY AND COLD AS ARCTIC HIGH PRESSURE BEARS DOWN OVER THE REGION. MODELS KEEP US UNDER A NORTHWEST FLOW ALOFT AS THIS HIGH PRESSURE MOVES ON TO THE SOUTHEAST FRIDAY AND SATURDAY. THEN IT WILL BECOME DRY AND WARMER THAN NORMAL BY SATURDAY AS A SOUTHERLY FLOW DEVELOPS ACROSS OUR REGION. UNFORTUNATELY THE SLIGHTLY WARMER WEATHER WILL BE BRIEF AS ANOTHER UPPER TROUGH MOVES ACROSS THE GREAT LAKES REGION. THIS FEATURE WILL BRING CHANCES FOR SNOW NORTH OF THE I-70 CORRIDOR AND RAIN GENERALLY SOUTH OF THIS FREQUENTLY USED BOUNDARY. SNOW LOOKS POSSIBLE ALL COUNTIES BY SUNDAY NIGHT. IN TERMS OF TEMPERATURES...SUPERBLEND GUIDANCE SEEMED VERY REASONABLE AND CLOSE TO MOS SO DID NOT NEED TO MAKE MANY ADJUSTMENTS TO FORECAST. && .AVIATION /DISCUSSION FOR THE 021800Z TAF ISSUANCE/... ISSUED AT 1250 PM EST MON FEB 2 2015 WIDELY SCATTERED LIGHT SNOW SHOWERS AND/OR FLURRIES ARE STILL IMPACTING A FEW OF THE TERMINALS EARLY THIS AFTERNOON BEFORE THEY COME TO AN END IN THE NEXT COUPLE OF HOURS. (AROUND 20-22Z) THESE AREAS ARE CAUSING MVFR CEILINGS AND IN SOME CASES VISIBILITIES OF 5SM. OTHERWISE THE REST OF THE TAF PERIOD WILL BE DRY AND OVERCAST WITH HIGH CLOUDS AND VFR CONDITIONS. WINDS HAVE ALREADY BEGUN TO DECREASE THIS AFTERNOON AND MOST GUSTS HAVE ABATED...SAVE FOR A FEW LOCATIONS SUCH AS KIND. WINDS WILL BECOME WEST OR SOUTHWEST 5 TO 8 KNOTS TONIGHT AS PRESSURE GRADIENT SLACKENS FURTHER. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD NEAR TERM...CP SHORT TERM...TDUD LONG TERM....SMF AVIATION...SMF 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
1257 PM EST MON FEB 2 2015 .UPDATE... THE AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 254 AM EST MON FEB 2 2015 LIGHT SNOW BANDS ON THE BACK SIDE OF RETREATING LOW WILL PERSIST THIS MORNING ACROSS CENTRAL INDIANA...BUT HIGH PRESSURE WILL STRENGTHEN BY THIS AFTERNOON. AFTER CHILLY TEMPERATURES TODAY...THERE WILL BE A WARM UP BY TOMORROW. HOWEVER...A COLD FRONT PROGGED FOR TUESDAY NIGHT WILL BRING LIGHT SNOW SHOWERS THROUGH WEDNESDAY NIGHT. COLDER BUT DRY WEATHER CAN BE EXPECTED AT THE END OF THE WEEK AS HIGH PRESSURE RE-ESTABLISHES ITSELF OVER THE AREA. FURTHER OUT...THE NEXT SYSTEM IS SET TO MOVE THROUGH THE REGION NEXT WEEKEND. && .NEAR TERM /REST OF TODAY/... ISSUED AT 1008 AM EST MON FEB 2 2015 RADAR MOSAIC AT 10 AM SHOWS SCATTERED FLURRIES AND A SMALL BAND OF LIGHT SNOW SHOWERS MOVING SOUTH SOUTHEAST THROUGH CENTRAL INDIANA. SHORT TERM MODELS ARE NOT DOING A GREAT JOB RESOLVING THESE PROBABLY DUE TO THEIR RELATIVELY LOCAL NATURE. THUS EVEN THOUGH HRRR AND RAP ARE NOT SHOWING MUCH OF ANYTHING GOING LATE THIS MORNING AND INTO THE AFTERNOON...BASED ON SATELLITE OBSERVATIONS...WIND DIRECTIONS AND TRENDS HAVE ADDED ISOLATED SNOW SHOWERS WITH SCATTERED FLURRIES INTO EARLY AFTERNOON FOR MOST OF THE AREA. ALSO KEPT POPS IN THE LATER AFTERNOON ALIGNED WITH POSSIBLE LAKE EFFECT BAND MIGRATING EASTWARD ACROSS THE NORTHERN COUNTIES. ALSO ADDED SOME FLURRIES ACROSS THE NORTHERN HALF OR SO OF THE AREA THROUGH THE AFTERNOON WITH THE NORTHERLY FLOW OFF THE LAKE AND CYCLONIC FLOW EXITING THE AREA. INCREASED CLOUD COVER INTO THE MID AFTERNOON ALSO BASED ON SATELLITE TRENDS AND ENHANCED LAKE EFFECT CLOUDS. && .SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/... ISSUED AT 254 AM EST MON FEB 2 2015 THE FOCUS OF THE SHORT TERM PERIOD IS A COLD FRONT PROGGED FOR TUESDAY NIGHT THROUGH WEDNESDAY NIGHT. FIRST...STRONG SUBSIDENCE OVER CENTRAL INDIANA WILL RESULT IN DRY CONDITIONS FROM TONIGHT THROUGH TOMORROW. WEAK RADIATIONAL COOLING TONIGHT WILL ALLOW TEMPS TO DIP INTO THE SINGLE DIGITS AND TEENS...THUS RESULTING IN WIND CHILLS BELOW ZERO OVER THE NORTHERN HALF OF THE FORECAST AREA. FOCUS THEN TURNS TO THE IMPENDING COLD FRONT PASSAGE ON TUESDAY NIGHT. LIGHT SNOW SHOULD START SPREADING ACROSS THE AREA FROM NORTH TO SOUTH ON TUESDAY NIGHT. THE BEST DYNAMICS WITH FRONT WILL BE ON WEDNESDAY AND WEDNESDAY NIGHT. AS OF NOW...WILL GO WITH ALL SNOW FORECAST DUE TO THE COLD AIR ALOFT. HOWEVER...CONCERNED WITH TEMPERATURES TOPPING OFF IN THE LOW 40S ACROSS THE SOUTHERN COUNTIES ON WEDNESDAY...POSSIBLY CREATING MORE OF A RAIN/SNOW MIX DURING THE DAY. ANY LINGERING PRECIP ON WEDNESDAY NIGHT SHOULD DEFINITELY BE IN THE FORM OF SNOW THOUGH AS TEMPERATURES PLUMMET INTO THE SINGLE DIGITS AND TEENS BEHIND COLD FRONT. && .LONG TERM /THURSDAY THROUGH SUNDAY/... ISSUED AT 345 AM EST SUN FEB 2 2015 THE LONG TERM WILL START OUT DRY AND COLD AS ARCTIC HIGH PRESSURE OVER IOWA THURSDAY MORNING MOVES EAST ACROSS OUR REGION THURSDAY NIGHT. MODELS KEEP US UNDER A NORTHWEST FLOW ALOFT AS THIS HIGH PRESSURE MOVES ON TO THE SOUTHEAST FRIDAY AND SATURDAY. IT WILL BECOME DRY AND WARMER BY SATURDAY AS A SOUTHERLY FLOW DEVELOPS ACROSS OUR REGION. MODEL ENSEMBLES INDICATE AN UPPER TROUGH WILL DIG INTO OUR REGION OVER THE 2ND HALF OF THE WEEKEND. THERE IS ALSO A SURFACE LOW WHICH WILL TRACK ACROSS SOUTHERN INDIANA SUNDAY WHICH WILL RESULT IN CHANCES OF PRECIPITATION FOR SATURDAY NIGHT AND SUNDAY. THE 00Z EURO PULLS MORE COLD AIR INTO NORTH AND CENTRAL SECTIONS BY SUNDAY AND LOW LEVEL THICKNESS INDICATE PRECIPITATION SHOULD CHANGE OVER TO SNOW NORTH HALF BY SUNDAY. IN THE SOUTH...ANY PRECIPITATION SHOULD CONTINUE AS ALL RAIN. CONCERNING TEMPERATURES...WENT WITH A MOS BLEND THURSDAY THROUGH SATURDAY AND SHAVED A FEW DEGREES NORTH HALF SUNDAY BASED ON THE COLDER TREND OF THE EURO. && .AVIATION /DISCUSSION FOR THE 021800Z TAF ISSUANCE/... ISSUED AT 1250 PM EST MON FEB 2 2015 WIDELY SCATTERED LIGHT SNOW SHOWERS AND/OR FLURRIES ARE STILL IMPACTING A FEW OF THE TERMINALS EARLY THIS AFTERNOON BEFORE THEY COME TO AN END IN THE NEXT COUPLE OF HOURS. (AROUND 20-22Z) THESE AREAS ARE CAUSING MVFR CEILINGS AND IN SOME CASES VISIBILITIES OF 5SM. OTHERWISE THE REST OF THE TAF PERIOD WILL BE DRY AND OVERCAST WITH HIGH CLOUDS AND VFR CONDITIONS. WINDS HAVE ALREADY BEGUN TO DECREASE THIS AFTERNOON AND MOST GUSTS HAVE ABATED...SAVE FOR A FEW LOCATIONS SUCH AS KIND. WINDS WILL BECOME WEST OR SOUTHWEST 5 TO 8 KNOTS TONIGHT AS PRESSURE GRADIENT SLACKENS FURTHER. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && $$ SYNOPSIS...TDUD NEAR TERM...CP SHORT TERM...TDUD LONG TERM...JH AVIATION...SMF 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 SHREVEPORT LA
1114 AM CST MON FEB 2 2015 .AVIATION... VFR SKC CONDITIONS AREAWIDE TO CONTINUE ACROSS AREA...WITH MID AND UPPER LVL CLOUDINESSS IN SOUTH TX...GRADUALLY WORKING ITS WAY NORTH TO ALONG AND SOUTH OF I-20 CORRIDOR AFTER 03/06Z. AS PRESSURE GRADIENT RELAXES THIS AFTN...NORTHERLY WINDS TO REMAIN MOSTLY AT 5 TO 10 KTS...DECOUPLING BTWN 02/22-23Z./VII/. && .PREV DISCUSSION... /ISSUED 1058 AM CST MON FEB 2 2015/ DISCUSSION... CANADIAN SFC RIDGING HAS SETTLED S ACROSS THE SRN PLAINS THIS MORNING...WITH THE RIDGE EXPECTED TO SHIFT SE INTO THE REGION THIS AFTERNOON AND EVENING. THIS WILL RESULT IN A MORE RELAXED PRESSURE GRADIENT BY AFTERNOON...WITH WINDS DIMINISHING FURTHER WITH TIME. THE BACK EDGE OF THE STRAOCU FIELD OVER SE AR/NE LA SHOULD PERSIST THROUGH THE AFTERNOON AS THEY SINK S...POSSIBLY SKIRTING ERN UNION COUNTY AR AS WELL AS THE ERN NCNTRL LA PARISHES. OTHERWISE...ABUNDANT SUNSHINE IS EXPECTED TODAY...BEFORE WE SHOULD NOTE IN INCREASE IN THE THICKENING CIRRUS SHIELD THIS AFTERNOON/EVENING OVER DEEP E TX/SRN SECTIONS OF NCNTRL LA WELL AHEAD OF THE SRN BAJA CLOSED LOW. HAVE ADDED A LITTLE MORE SKY COVERAGE TO THE FORECAST THIS AFTERNOON/TONIGHT FOR THE CIRRUS...AS IT BEGINS TO EXPAND NEWRD OVERNIGHT. GIVEN THE EXTENSIVE SNOWPACK NOTED ON THE VISIBLE SATELLITE IMAGERY OVER THE NRN PLAINS/MIDWEST THIS MORNING...AND STRONG SFC RIDGING JUST TO THE S...16Z TEMPS HAVE FINALLY BEGUN TO APPROACH/EXCEED THE FREEZING MARK ALONG/N OF THE I-20 CORRIDOR...WITH ONLY A SLOW WARMUP EXPECTED BY AFTERNOON. DID TWEAK MAX TEMPS A DEGREE OR SO BASED ON THE HRRR 2M TEMPS...WHICH INITIALIZED WELL ON TEMPS THIS MORNING. BUT OTHERWISE...THE FORECAST REMAINS IN GOOD SHAPE. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 44 28 53 37 55 / 0 0 0 20 20 MLU 44 27 49 34 52 / 0 0 0 20 20 DEQ 42 24 52 33 54 / 0 0 0 0 20 TXK 41 27 51 39 56 / 0 0 0 10 20 ELD 42 25 51 33 55 / 0 0 0 10 20 TYR 43 32 55 40 57 / 0 0 0 20 20 GGG 44 29 54 36 57 / 0 0 0 20 20 LFK 48 31 56 41 57 / 0 0 20 30 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$
AREA FORECAST DISCUSSION
NWS SHREVEPORT LA
1058 AM CST MON FEB 2 2015 .DISCUSSION... CANADIAN SFC RIDGING HAS SETTLED S ACROSS THE SRN PLAINS THIS MORNING...WITH THE RIDGE EXPECTED TO SHIFT SE INTO THE REGION THIS AFTERNOON AND EVENING. THIS WILL RESULT IN A MORE RELAXED PRESSURE GRADIENT BY AFTERNOON...WITH WINDS DIMINISHING FURTHER WITH TIME. THE BACK EDGE OF THE STRAOCU FIELD OVER SE AR/NE LA SHOULD PERSIST THROUGH THE AFTERNOON AS THEY SINK S...POSSIBLY SKIRTING ERN UNION COUNTY AR AS WELL AS THE ERN NCNTRL LA PARISHES. OTHERWISE...ABUNDANT SUNSHINE IS EXPECTED TODAY...BEFORE WE SHOULD NOTE IN INCREASE IN THE THICKENING CIRRUS SHIELD THIS AFTERNOON/EVENING OVER DEEP E TX/SRN SECTIONS OF NCNTRL LA WELL AHEAD OF THE SRN BAJA CLOSED LOW. HAVE ADDED A LITTLE MORE SKY COVERAGE TO THE FORECAST THIS AFTERNOON/TONIGHT FOR THE CIRRUS...AS IT BEGINS TO EXPAND NEWRD OVERNIGHT. GIVEN THE EXTENSIVE SNOWPACK NOTED ON THE VISIBLE SATELLITE IMAGERY OVER THE NRN PLAINS/MIDWEST THIS MORNING...AND STRONG SFC RIDGING JUST TO THE S...16Z TEMPS HAVE FINALLY BEGUN TO APPROACH/EXCEED THE FREEZING MARK ALONG/N OF THE I-20 CORRIDOR...WITH ONLY A SLOW WARMUP EXPECTED BY AFTERNOON. DID TWEAK MAX TEMPS A DEGREE OR SO BASED ON THE HRRR 2M TEMPS...WHICH INITIALIZED WELL ON TEMPS THIS MORNING. BUT OTHERWISE...THE FORECAST REMAINS IN GOOD SHAPE. ZONE UPDATE ALREADY OUT...GRIDS WILL BE AVAILABLE SHORTLY. 15 && .PRELIMINARY POINT TEMPS/POPS... SHV 44 28 53 37 55 / 0 0 0 20 20 MLU 44 27 49 34 52 / 0 0 0 20 20 DEQ 42 24 52 33 54 / 0 0 0 0 20 TXK 41 27 51 39 56 / 0 0 0 10 20 ELD 42 25 51 33 55 / 0 0 0 10 20 TYR 43 32 55 40 57 / 0 0 0 20 20 GGG 44 29 54 36 57 / 0 0 0 20 20 LFK 48 31 56 41 57 / 0 0 20 30 30 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...NONE. LA...NONE. OK...NONE. TX...NONE. && $$ 15
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
602 PM EST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 426 PM EST MON FEB 2 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A BROAD TROUGH FROM NRN HUDSON BAY INTO THE ERN CONUS RESULTING IN WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH WAS MOVING INTO NW ONTARIO AND NRN MN. AT THE SFC...A TROUGH EXTENDED FROM NW ONTARIO THROUGH NW MN INTO ERN SOUTH DAKOTA AS HIGH PRESSURE BUILDS INTO THE MID MS VALLEY. WINDS BACKING TO THE SW AHEAD OF THE TROUGH HAVE PUSHED THE LES OFFSHORE FROM THE CWA. VIS SATELLITE SHOWED POTENTIAL DEVELOPMENT OF AN LES BAND OFFSHORE FROM THE KEWEENAW BUT WAS LARGELY OBSCURED BY INCREASING MID/HIGH CLOUDS. TONIGHT...AS SFC TROF BEGINS TO SAG SE ACROSS THE CWA...A MODERATE TO POSSIBLY HEAVY DOMINANT LES BAND WILL GET PUSHED SOUTH ACROSS THE KEWEENAW PENINSULA. WITH 850 MB TEMPS NEAR -19C...CONVECTION/LIFT THROUGH THE 1K-3K FT DGZ...EXPECT THE POTENTIAL FOR SNOWFALL RATES IN EXCESS OF 1" PER HOUR AS LES BAND SAGS SOUTH ACROSS THE KEWEENAW. HOWEVER...SINCE THE BAND IS LIKELY TO MOVE QUICKLY ENOUGH TO LIMIT OVERALL SNOWFALL AMOUNTS...TOTALS GENERALLY IN THE 2 TO 6 INCH RANGE ARE EXPECTED. SO...THE LES ADVISORY LOOKS ON TRACK. EXPECT THE SNOW TO BEGIN TO DIMINISH AND TRANSITION TO MULTIPLE WIND PARALLEL BANDS AS THE WINDS VEER TO THE NW. OTHERWISE...LES SHOULD REMAIN OFFSHORE FROM THE ERN CWA UNTIL LATE AS WINDS ONLY VEER FROM WSW TO W. TUE...280-290 FLOW LES WILL CONTINUE WITH 850 MB TEMPS REMAINING AROUND -19C. LOWERING INVERSION HEIGHTS BELOW 4K FT WILL LIMIT POTENTIAL FOR ADDITIONAL ACCUMULATIONS WITH ONLY AN INCH OR TWO WEST AND 1 TO 3 INCHES EAST...MAINLY EAST OF MUNISING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 341 PM EST MON FEB 2 2015 THE UPPER GREAT LAKES REGION REMAINS LOCKED IN NORTHWESTERLY FLOW ALOFT AS A WEAK RIDGE REMAINS IN PLACE OVER THE WESTERN CONUS AND AN UPPER LOW SPINS OVER NORTHERN HUDSON BAY. THIS NORTHWESTERLY FLOW WILL CONTINUE TO BRING OCCASIONAL DISTURBANCES OVER THE AREA AND KEEP BELOW NORMAL TEMPERATURES IN PLACE THROUGH THE PERIOD. AT THE START OF THE PERIOD...A WEAK SHORTWAVE WILL BE SLIDING JUST TO THE SOUTH OF THE CWA...ALTHOUGH THERE COULD BE A LIGHT SNOW SHOWER BRUSHING SOUTHERN MENOMINEE COUNTY ON TUESDAY EVENING. MEANWHILE...LIGHT LAKE EFFECT SNOW WILL BE ONGOING IN THE WEST-NORTHWEST WIND SNOW BELTS OF NORTHERN LAKE SUPERIOR. WHILE AMOUNTS WON/T BE ANYTHING TOO SIGNIFICANT INITIALLY TUESDAY EVENING...A STRONGER SHORTWAVE WILL DROP SOUTHEAST ACROSS THE AREA LATE TUESDAY NIGHT AND WEDNESDAY...BRINGING MUCH COLDER TEMPERATURES ALOFT TO THE AREA UNDER NORTHWEST WINDS. THESE TEMPERATURES (850MB TEMPS FALLING FROM -19C AT 00Z WEDNESDAY TO -26C BY 00Z THURSDAY) WILL HELP STEEPEN THE MID LEVEL LAPSE RATES AND ALLOW THE INVERSION HEIGHTS TO RISE FROM 5-6KFT TO 10-11KFT. THUS...WOULD EXPECT THE INTENSITY OF THE SNOW SHOWERS TO QUICKLY INCREASE LATE TUESDAY NIGHT AND WEDNESDAY MORNING AS THE INVERSION HEIGHTS RISE AND THERE IS ASSISTANCE (MOISTURE/FORCING) FROM THE SHORTWAVE. WITH FAIRLY UNIFORM NORTHWESTERLY WINDS DEVELOPING DURING THE TIME OF INTENSIFICATION...WOULD EXPECT MAINLY MULTIBAND LES ONCE IT BECOMES ESTABLISHED ON WEDNESDAY...ALTHOUGH THE LAND BREEZE OFF ONTARIO (AND THE ICE IN THAT AREA OF LAKE SUPERIOR) ON WEDNESDAY NIGHT COULD LEAD TO A MORE DOMINATE BAND DEVELOPING SOMEWHERE BETWEEN PICTURED ROCKS AND WHITEFISH POINT AND WILL FOCUS THE HIGHER POPS/SNOWFALL AMOUNTS THERE. THE MAIN LIMITING FACTOR TO SNOWFALL AMOUNTS WILL BE THE COLD AIR KEEPING MUCH OF THE CLOUD OUTSIDE OF THE DGZ AND KEEP RATIOS BELOW 20 TO ONE AND AMOUNTS LIGHTER. BUT WITH THOSE SMALLER FLAKES...IT WILL BE VERY EFFICIENT AT REDUCING VISIBILITIES AND THAT WILL LIKELY BE ONE OF THE BIGGEST IMPACTS WITH THIS EVENT. WINDS WILL BACK WEDNESDAY NIGHT AND THURSDAY AS THE SURFACE RIDGE MOVES THROUGH THE AREA. THIS WILL CONTINUE TO LOWER INVERSION HEIGHTS ACROSS THE AREA AND SHIFT WINDS TO THE SOUTHWEST BY THURSDAY EVENING. THUS...WILL SHOW A WEST TO EAST DIMINISHING TREND WEDNESDAY NIGHT INTO THURSDAY MORNING BEFORE THE SNOW MOVES OFF SHORE OF THE U.P. BY THURSDAY AFTERNOON. MODELS BEGIN TO DIFFER ON SOME OF THE SMALLER DETAILS HEADING INTO THE WEEKEND...AS A WEAK SHORTWAVE SLIDES SOUTHEAST ACROSS THE GREAT LAKES REGION. THIS WILL SPREAD AN AREA OF SNOW SHOWERS EAST-SOUTHEAST ACROSS THE CWA FRIDAY AFTERNOON/NIGHT ON THE NOSE OF THE MID-LEVEL WARM AIR ADVECTION. WITH DIFFERENCES IN THE TRACK OF THE BEST SNOWFALL...WILL SHOW CHANCE POPS MOVING ACROSS THE CWA. BEHIND THIS WAVE...A HIGH PRESSURE RIDGE (FROM A HIGH IN CENTRAL CANADA) WILL NOSE SOUTHEAST INTO THE CWA AND LEAD TO NORTHERLY FLOW ACROSS LAKE SUPERIOR. WITH 850MB TEMPS FALLING TO BETWEEN -14 AND -22C BY SATURDAY EVENING...WOULD EXPECT LAKE EFFECT SNOW TO DEVELOP LATE FRIDAY NIGHT AND INTO SATURDAY. THE SUBSIDENCE INVERSION (3-4KFT) WILL LIKELY KEEP THE INTENSITY IN CHECK BUT WILL NEED TO WATCH THE AMOUNT OF COLD AIR. IF THE WARMER SOLUTION SHOWN BY THE 12Z GFS PANS OUT...MUCH OF THE CLOUD WOULD BE WITHIN THE DGZ AND LEAD TO A FEW INCHES OF FLUFFY ACCUMULATION. OTHERWISE...WOULD EXPECT LIMITED ACCUMULATIONS THROUGH SUNDAY NIGHT WITH THE NNE FLOW DUE TO THE PERSISTENT SUBSIDENCE INVERSION. THE HIGH WILL SHIFT EAST OF THE AREA ON MONDAY...ALLOWING SOUTHERLY FLOW TO DEVELOP AND DIMINISH THE LAKE EFFECT. AS FOR TEMPS...EXPECT BELOW NORMAL VALUES FOR MOST OF THE PERIOD...WITH THE ONLY REPRIEVE BEING ON FRIDAY WHEN HIGHS RISE INTO THE UPPER TEENS AND LOWER 20S. WITH CLEARING EXPECTED ON WEDNESDAY NIGHT...WOULD EXPECT A PRETTY COLD NIGHT OVER THE INTERIOR WEST AND HAVE TEMPERATURES FALLING INTO THE TEENS BELOW ZERO. AS THIS OCCURS...THE WINDS WILL REALLY BE DIMINISHING AND EXPECT THAT TO KEEP WIND CHILLS IN CHECK FOR LATE WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. WILL CONTINUE TO MENTION IN THE HWO DUE TO THE COLD FACTOR...BUT WITH WINDS LIKELY BEING BELOW 10MPH WE SHOULDN/T NEED A WIND CHILL ADVISORY. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 602 PM EST MON FEB 2 2015 INCREASING MOISTURE LATE TONIGHT WITH THE ARRIVAL OF A SFC TROUGH FROM NW OF LAKE SUPERIOR WILL ALLOW FOR MVFR CONDITIONS TO RETURN AT BOTH KIWD AND KSAW WITH SOME LIGHT LES EXPECTED AT KIWD LATE TONIGHT. AT KCMX...MVFR CIGS SHOULD PERSIST THROUGH THE FCST PERIOD. EXPECT IFR VSBYS TO RETURN AS A DOMINANT LES BAND IS LIKELY TO DEVELOP AND SLOWLY SAG TO THE SOUTH ACROSS THE KEWEENAW PENINSULA. VSBYS SHOULD IMPROVE TO MVFR LATE TONIGHT AS WINDS SHIFT MORE NW AND THE DOMINANT LES BAND MOVES SOUTH OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON FEB 2 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH TODAY... THEN TURN TO THE NORTHWEST BEHIND THE TROUGH LATE TONIGHT AND TUESDAY. WEST WIND GUSTS OVER THE ERN HALF OF LAKE MAY BRIEFLY APPROACH GALE FORCE THIS EVENING...OTHER EXPECT WINDS AT OR BLO 30 KTS. HEAVY FREEZING SPRAY IS EXPECTED OVER PORTIONS OF THE WRN LAKE THIS AFTERNOON INTO THIS EVENING AND ERN LK SUPERIOR TONIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES ON WEDNESDAY. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON LATE FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 6 AM EST TUESDAY FOR LSZ266- 267. HEAVY FREEZING SPRAY WARNING UNTIL 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...07 MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
426 PM EST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 426 PM EST MON FEB 2 2015 WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A BROAD TROUGH FROM NRN HUDSON BAY INTO THE ERN CONUS RESULTING IN WNW FLOW THROUGH THE NRN GREAT LAKES. A WEAK SHORTWAVE TROUGH WAS MOVING INTO NW ONTARIO AND NRN MN. AT THE SFC...A TROUGH EXTENDED FROM NW ONTARIO THROUGH NW MN INTO ERN SOUTH DAKOTA AS HIGH PRESSURE BUILDS INTO THE MID MS VALLEY. WINDS BACKING TO THE SW AHEAD OF THE TROUGH HAVE PUSHED THE LES OFFSHORE FROM THE CWA. VIS SATELLITE SHOWED POTENTIAL DEVELOPMENT OF AN LES BAND OFFSHORE FROM THE KEWEENAW BUT WAS LARGELY OBSCURED BY INCREASING MID/HIGH CLOUDS. TONIGHT...AS SFC TROF BEGINS TO SAG SE ACROSS THE CWA...A MODERATE TO POSSIBLY HEAVY DOMINANT LES BAND WILL GET PUSHED SOUTH ACROSS THE KEWEENAW PENINSULA. WITH 850 MB TEMPS NEAR -19C...CONVECTION/LIFT THROUGH THE 1K-3K FT DGZ...EXPECT THE POTENTIAL FOR SNOWFALL RATES IN EXCESS OF 1" PER HOUR AS LES BAND SAGS SOUTH ACROSS THE KEWEENAW. HOWEVER...SINCE THE BAND IS LIKELY TO MOVE QUICKLY ENOUGH TO LIMIT OVERALL SNOWFALL AMOUNTS...TOTALS GENERALLY IN THE 2 TO 6 INCH RANGE ARE EXPECTED. SO...THE LES ADVISORY LOOKS ON TRACK. EXPECT THE SNOW TO BEGIN TO DIMINISH AND TRANSITION TO MULTIPLE WIND PARALLEL BANDS AS THE WINDS VEER TO THE NW. OTHERWISE...LES SHOULD REMAIN OFFSHORE FROM THE ERN CWA UNTIL LATE AS WINDS ONLY VEER FROM WSW TO W. TUE...280-290 FLOW LES WILL CONTINUE WITH 850 MB TEMPS REMAINING AROUND -19C. LOWERING INVERSION HEIGHTS BELOW 4K FT WILL LIMIT POTENTIAL FOR ADDITIONAL ACCUMULATIONS WITH ONLY AN INCH OR TWO WEST AND 1 TO 3 INCHES EAST...MAINLY EAST OF MUNISING. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 341 PM EST MON FEB 2 2015 THE UPPER GREAT LAKES REGION REMAINS LOCKED IN NORTHWESTERLY FLOW ALOFT AS A WEAK RIDGE REMAINS IN PLACE OVER THE WESTERN CONUS AND AN UPPER LOW SPINS OVER NORTHERN HUDSON BAY. THIS NORTHWESTERLY FLOW WILL CONTINUE TO BRING OCCASIONAL DISTURBANCES OVER THE AREA AND KEEP BELOW NORMAL TEMPERATURES IN PLACE THROUGH THE PERIOD. AT THE START OF THE PERIOD...A WEAK SHORTWAVE WILL BE SLIDING JUST TO THE SOUTH OF THE CWA...ALTHOUGH THERE COULD BE A LIGHT SNOW SHOWER BRUSHING SOUTHERN MENOMINEE COUNTY ON TUESDAY EVENING. MEANWHILE...LIGHT LAKE EFFECT SNOW WILL BE ONGOING IN THE WEST-NORTHWEST WIND SNOW BELTS OF NORTHERN LAKE SUPERIOR. WHILE AMOUNTS WON/T BE ANYTHING TOO SIGNIFICANT INITIALLY TUESDAY EVENING...A STRONGER SHORTWAVE WILL DROP SOUTHEAST ACROSS THE AREA LATE TUESDAY NIGHT AND WEDNESDAY...BRINGING MUCH COLDER TEMPERATURES ALOFT TO THE AREA UNDER NORTHWEST WINDS. THESE TEMPERATURES (850MB TEMPS FALLING FROM -19C AT 00Z WEDNESDAY TO -26C BY 00Z THURSDAY) WILL HELP STEEPEN THE MID LEVEL LAPSE RATES AND ALLOW THE INVERSION HEIGHTS TO RISE FROM 5-6KFT TO 10-11KFT. THUS...WOULD EXPECT THE INTENSITY OF THE SNOW SHOWERS TO QUICKLY INCREASE LATE TUESDAY NIGHT AND WEDNESDAY MORNING AS THE INVERSION HEIGHTS RISE AND THERE IS ASSISTANCE (MOISTURE/FORCING) FROM THE SHORTWAVE. WITH FAIRLY UNIFORM NORTHWESTERLY WINDS DEVELOPING DURING THE TIME OF INTENSIFICATION...WOULD EXPECT MAINLY MULTIBAND LES ONCE IT BECOMES ESTABLISHED ON WEDNESDAY...ALTHOUGH THE LAND BREEZE OFF ONTARIO (AND THE ICE IN THAT AREA OF LAKE SUPERIOR) ON WEDNESDAY NIGHT COULD LEAD TO A MORE DOMINATE BAND DEVELOPING SOMEWHERE BETWEEN PICTURED ROCKS AND WHITEFISH POINT AND WILL FOCUS THE HIGHER POPS/SNOWFALL AMOUNTS THERE. THE MAIN LIMITING FACTOR TO SNOWFALL AMOUNTS WILL BE THE COLD AIR KEEPING MUCH OF THE CLOUD OUTSIDE OF THE DGZ AND KEEP RATIOS BELOW 20 TO ONE AND AMOUNTS LIGHTER. BUT WITH THOSE SMALLER FLAKES...IT WILL BE VERY EFFICIENT AT REDUCING VISIBILITIES AND THAT WILL LIKELY BE ONE OF THE BIGGEST IMPACTS WITH THIS EVENT. WINDS WILL BACK WEDNESDAY NIGHT AND THURSDAY AS THE SURFACE RIDGE MOVES THROUGH THE AREA. THIS WILL CONTINUE TO LOWER INVERSION HEIGHTS ACROSS THE AREA AND SHIFT WINDS TO THE SOUTHWEST BY THURSDAY EVENING. THUS...WILL SHOW A WEST TO EAST DIMINISHING TREND WEDNESDAY NIGHT INTO THURSDAY MORNING BEFORE THE SNOW MOVES OFF SHORE OF THE U.P. BY THURSDAY AFTERNOON. MODELS BEGIN TO DIFFER ON SOME OF THE SMALLER DETAILS HEADING INTO THE WEEKEND...AS A WEAK SHORTWAVE SLIDES SOUTHEAST ACROSS THE GREAT LAKES REGION. THIS WILL SPREAD AN AREA OF SNOW SHOWERS EAST-SOUTHEAST ACROSS THE CWA FRIDAY AFTERNOON/NIGHT ON THE NOSE OF THE MID-LEVEL WARM AIR ADVECTION. WITH DIFFERENCES IN THE TRACK OF THE BEST SNOWFALL...WILL SHOW CHANCE POPS MOVING ACROSS THE CWA. BEHIND THIS WAVE...A HIGH PRESSURE RIDGE (FROM A HIGH IN CENTRAL CANADA) WILL NOSE SOUTHEAST INTO THE CWA AND LEAD TO NORTHERLY FLOW ACROSS LAKE SUPERIOR. WITH 850MB TEMPS FALLING TO BETWEEN -14 AND -22C BY SATURDAY EVENING...WOULD EXPECT LAKE EFFECT SNOW TO DEVELOP LATE FRIDAY NIGHT AND INTO SATURDAY. THE SUBSIDENCE INVERSION (3-4KFT) WILL LIKELY KEEP THE INTENSITY IN CHECK BUT WILL NEED TO WATCH THE AMOUNT OF COLD AIR. IF THE WARMER SOLUTION SHOWN BY THE 12Z GFS PANS OUT...MUCH OF THE CLOUD WOULD BE WITHIN THE DGZ AND LEAD TO A FEW INCHES OF FLUFFY ACCUMULATION. OTHERWISE...WOULD EXPECT LIMITED ACCUMULATIONS THROUGH SUNDAY NIGHT WITH THE NNE FLOW DUE TO THE PERSISTENT SUBSIDENCE INVERSION. THE HIGH WILL SHIFT EAST OF THE AREA ON MONDAY...ALLOWING SOUTHERLY FLOW TO DEVELOP AND DIMINISH THE LAKE EFFECT. AS FOR TEMPS...EXPECT BELOW NORMAL VALUES FOR MOST OF THE PERIOD...WITH THE ONLY REPRIEVE BEING ON FRIDAY WHEN HIGHS RISE INTO THE UPPER TEENS AND LOWER 20S. WITH CLEARING EXPECTED ON WEDNESDAY NIGHT...WOULD EXPECT A PRETTY COLD NIGHT OVER THE INTERIOR WEST AND HAVE TEMPERATURES FALLING INTO THE TEENS BELOW ZERO. AS THIS OCCURS...THE WINDS WILL REALLY BE DIMINISHING AND EXPECT THAT TO KEEP WIND CHILLS IN CHECK FOR LATE WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. WILL CONTINUE TO MENTION IN THE HWO DUE TO THE COLD FACTOR...BUT WITH WINDS LIKELY BEING BELOW 10MPH WE SHOULDN/T NEED A WIND CHILL ADVISORY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1256 PM EST MON FEB 2 2015 INCREASING MOISTURE LATE TONIGHT WITH THE ARRIVAL OF A SFC TROUGH FROM NW OF LAKE SUPERIOR WILL ALLOW FOR MVFR CONDITIONS TO RETURN AT BOTH KIWD AND KSAW WITH SOME LIGHT LES EXPECTED AT KIWD. AT KCMX...MVFR CIGS SHOULD PERSIST THROUGH THE FCST PERIOD. OCNL IFR VSBY IS EXPECTED THROUGH MID AFTERNOON UNTIL WINDS BACK ENOUGH TO THE SW TO PUSH THE LES BANDS TO THE NORTH. HOWEVER...LATE THIS EVENING INTO THE OVERNIGHT HOURS...EXPECT IFR VSBYS TO RETURN AS A DOMINANT LES BAND IS LIKELY TO DEVELOP AND SLOWLY SAG TO THE SOUTH ACROSS THE KEWEENAW PENINSULA. VSBYS SHOULD IMPROVE TO MVFR LATE TONIGHT AS WINDS SHIFT MORE NW AND THE DOMINANT LES BAND MOVES SOUTH OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON FEB 2 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH TODAY... THEN TURN TO THE NORTHWEST BEHIND THE TROUGH LATE TONIGHT AND TUESDAY. WEST WIND GUSTS OVER THE ERN HALF OF LAKE MAY BRIEFLY APPROACH GALE FORCE THIS EVENING...OTHER EXPECT WINDS AT OR BLO 30 KTS. HEAVY FREEZING SPRAY IS EXPECTED OVER PORTIONS OF THE WRN LAKE THIS AFTERNOON INTO THIS EVENING AND ERN LK SUPERIOR TONIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES ON WEDNESDAY. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON LATE FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 6 AM EST TUESDAY FOR LSZ266- 267. HEAVY FREEZING SPRAY WARNING UNTIL 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...JLB LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
341 PM EST MON FEB 2 2015 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 525 AM EST MON FEB 2 2015 ...POTENTIAL FOR MODERATE TO POSSIBLY HEAVY LES OVER THE KEWEENAW LATE TODAY AND TONIGHT... WV IMAGERY AND RUC ANALYSIS INDICATED A MID/UPPER LEVEL RIDGE OVER THE WRN CONUS AND A TROUGH FROM NRN HUDSON BAY INTO ERN CANADA RESULTING IN WNW NRN STREAM FLOW THROUGH THE NRN GREAT LAKES. AT THE SFC...A DRY NRLY FLOW PREVAILED ACROSS LAKE SUPERIOR AND UPPER MI BETWEEN A RIDGE OVER THE CENTRAL PLAINS AND A 996 MB LOW MOVING THROUGH THE OHIO VALLEY. RADAR LOOP SHOWS LINGERING LES OVER ERN MQT AND ALGER COUNTIES EARLY THIS MORNING WITH 900 MB TEMPS AROUND -21C PROVIDING ENOUGH INSTABILITY FOR PERSISTENT LES. HOWEVER...WITH INVERSION HEIGHTS DROPPING TO AROUND 3K FT AND THE DGZ NEAR LAKE SFC LES ACCUMULATION SHOULD BE LIMITED TO A RANGE FROM 1 TO POSSIBLY 3 INCHES THIS MORNING. TODAY...EXPECT LINGERING LES FOR NCNTRL ZONES TO BE PUSHED OFFSHORE AS FLOW BACKS IN RESPONSE TO A TROUGH DEVELOPING OVER NRN MN AND THE HIGH PRES SHIFTING INTO THE MID MISSISSIPPI VALLEY. TEMPS WILL REMAIN BELOW NORMAL IN THE 10-15F RANGE. HOWEVER...LATE IN THE DAY LOW-LVL CONVERGENCE WILL INCREASE OVER THE TIP OF KEWEENAW PENINSULA AS A SHORTWAVE DISTURBANCE AND THE ASSOC SFC TROUGH OVER NRN MN DROPS ACROSS NCNTRL AND ERN LAKE SUPERIOR. THIS ENHANCED CONVERGENCE COMBINED WITH WEAK LIFT AND MOISTURE DEEPENING TO 10 KFT SHOULD LEAD TO DOMINANT LES BAND FORMING OVER THE TIP OF THE KEWEENAW LATE TODAY WITH A POTENTIAL FOR MODERATE TO POSSIBLY HEAVY SNOW. TONIGHT...AS SFC TROF BEGINS TO SAG SE ACROSS THE CWA...MODERATE TO POSSIBLY HEAVY DOMINANT LES BAND WILL GET PUSHED SOUTH ACROSS THE KEWEENAW PENINSULA. WITH H85 TEMPS NEAR -20C...STEEPENING 1000-850MB LAPSE RATES AND ENHANCED LIFT/OMEGA THROUGH THE DGZ...EXPECT THE POTENTIAL FOR SNOWFALL RATES IN EXCESS OF 1" PER HOUR AS LES BAND SAGS SOUTH ACROSS THE KEWEENAW. DOES APPEAR THAT THE HEAVIEST SNOW WILL NOT LAST MORE THAN A FEW HOURS. WIND GUSTS 20-25 MPH WILL BLOW/DRIFT SNOW AS WELL. GIVEN ABOVE FAVORABLE FACTORS FELT THAT LES ADVISORY WAS WARRANTED FOR OVER THE KEWEENAW LATE TODAY THROUGH TONIGHT. EXPECT SNOW TO BEGIN TO TAPER OFF AND BECOME MORE MULTIBAND AS DEEPER MOISTURE DEPARTS IN THE WAKE OF THE EXITING TROUGH. LOOK FOR 3-6 INCH SNOWFALL ACCUMULATION OVER KEWEENAW COUNTY WITH 3-5 INCHES OVER NORTHERN HOUGHTON COUNTY. ELSEWHERE THAN SCT LES OVER THE FAR WEST...EXPECT LITTLE IF ANY SNOW ELSEWHERE AS WESTERLY FLOW SHOULD KEEP REST OF LES OUT OVER LAKE SUPERIOR. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 341 PM EST MON FEB 2 2015 THE UPPER GREAT LAKES REGION REMAINS LOCKED IN NORTHWESTERLY FLOW ALOFT AS A WEAK RIDGE REMAINS IN PLACE OVER THE WESTERN CONUS AND AN UPPER LOW SPINS OVER NORTHERN HUDSON BAY. THIS NORTHWESTERLY FLOW WILL CONTINUE TO BRING OCCASIONAL DISTURBANCES OVER THE AREA AND KEEP BELOW NORMAL TEMPERATURES IN PLACE THROUGH THE PERIOD. AT THE START OF THE PERIOD...A WEAK SHORTWAVE WILL BE SLIDING JUST TO THE SOUTH OF THE CWA...ALTHOUGH THERE COULD BE A LIGHT SNOW SHOWER BRUSHING SOUTHERN MENOMINEE COUNTY ON TUESDAY EVENING. MEANWHILE...LIGHT LAKE EFFECT SNOW WILL BE ONGOING IN THE WEST-NORTHWEST WIND SNOW BELTS OF NORTHERN LAKE SUPERIOR. WHILE AMOUNTS WON/T BE ANYTHING TOO SIGNIFICANT INITIALLY TUESDAY EVENING...A STRONGER SHORTWAVE WILL DROP SOUTHEAST ACROSS THE AREA LATE TUESDAY NIGHT AND WEDNESDAY...BRINGING MUCH COLDER TEMPERATURES ALOFT TO THE AREA UNDER NORTHWEST WINDS. THESE TEMPERATURES (850MB TEMPS FALLING FROM -19C AT 00Z WEDNESDAY TO -26C BY 00Z THURSDAY) WILL HELP STEEPEN THE MID LEVEL LAPSE RATES AND ALLOW THE INVERSION HEIGHTS TO RISE FROM 5-6KFT TO 10-11KFT. THUS...WOULD EXPECT THE INTENSITY OF THE SNOW SHOWERS TO QUICKLY INCREASE LATE TUESDAY NIGHT AND WEDNESDAY MORNING AS THE INVERSION HEIGHTS RISE AND THERE IS ASSISTANCE (MOISTURE/FORCING) FROM THE SHORTWAVE. WITH FAIRLY UNIFORM NORTHWESTERLY WINDS DEVELOPING DURING THE TIME OF INTENSIFICATION...WOULD EXPECT MAINLY MULTIBAND LES ONCE IT BECOMES ESTABLISHED ON WEDNESDAY...ALTHOUGH THE LAND BREEZE OFF ONTARIO (AND THE ICE IN THAT AREA OF LAKE SUPERIOR) ON WEDNESDAY NIGHT COULD LEAD TO A MORE DOMINATE BAND DEVELOPING SOMEWHERE BETWEEN PICTURED ROCKS AND WHITEFISH POINT AND WILL FOCUS THE HIGHER POPS/SNOWFALL AMOUNTS THERE. THE MAIN LIMITING FACTOR TO SNOWFALL AMOUNTS WILL BE THE COLD AIR KEEPING MUCH OF THE CLOUD OUTSIDE OF THE DGZ AND KEEP RATIOS BELOW 20 TO ONE AND AMOUNTS LIGHTER. BUT WITH THOSE SMALLER FLAKES...IT WILL BE VERY EFFICIENT AT REDUCING VISIBILITIES AND THAT WILL LIKELY BE ONE OF THE BIGGEST IMPACTS WITH THIS EVENT. WINDS WILL BACK WEDNESDAY NIGHT AND THURSDAY AS THE SURFACE RIDGE MOVES THROUGH THE AREA. THIS WILL CONTINUE TO LOWER INVERSION HEIGHTS ACROSS THE AREA AND SHIFT WINDS TO THE SOUTHWEST BY THURSDAY EVENING. THUS...WILL SHOW A WEST TO EAST DIMINISHING TREND WEDNESDAY NIGHT INTO THURSDAY MORNING BEFORE THE SNOW MOVES OFF SHORE OF THE U.P. BY THURSDAY AFTERNOON. MODELS BEGIN TO DIFFER ON SOME OF THE SMALLER DETAILS HEADING INTO THE WEEKEND...AS A WEAK SHORTWAVE SLIDES SOUTHEAST ACROSS THE GREAT LAKES REGION. THIS WILL SPREAD AN AREA OF SNOW SHOWERS EAST-SOUTHEAST ACROSS THE CWA FRIDAY AFTERNOON/NIGHT ON THE NOSE OF THE MID-LEVEL WARM AIR ADVECTION. WITH DIFFERENCES IN THE TRACK OF THE BEST SNOWFALL...WILL SHOW CHANCE POPS MOVING ACROSS THE CWA. BEHIND THIS WAVE...A HIGH PRESSURE RIDGE (FROM A HIGH IN CENTRAL CANADA) WILL NOSE SOUTHEAST INTO THE CWA AND LEAD TO NORTHERLY FLOW ACROSS LAKE SUPERIOR. WITH 850MB TEMPS FALLING TO BETWEEN -14 AND -22C BY SATURDAY EVENING...WOULD EXPECT LAKE EFFECT SNOW TO DEVELOP LATE FRIDAY NIGHT AND INTO SATURDAY. THE SUBSIDENCE INVERSION (3-4KFT) WILL LIKELY KEEP THE INTENSITY IN CHECK BUT WILL NEED TO WATCH THE AMOUNT OF COLD AIR. IF THE WARMER SOLUTION SHOWN BY THE 12Z GFS PANS OUT...MUCH OF THE CLOUD WOULD BE WITHIN THE DGZ AND LEAD TO A FEW INCHES OF FLUFFY ACCUMULATION. OTHERWISE...WOULD EXPECT LIMITED ACCUMULATIONS THROUGH SUNDAY NIGHT WITH THE NNE FLOW DUE TO THE PERSISTENT SUBSIDENCE INVERSION. THE HIGH WILL SHIFT EAST OF THE AREA ON MONDAY...ALLOWING SOUTHERLY FLOW TO DEVELOP AND DIMINISH THE LAKE EFFECT. AS FOR TEMPS...EXPECT BELOW NORMAL VALUES FOR MOST OF THE PERIOD...WITH THE ONLY REPRIEVE BEING ON FRIDAY WHEN HIGHS RISE INTO THE UPPER TEENS AND LOWER 20S. WITH CLEARING EXPECTED ON WEDNESDAY NIGHT...WOULD EXPECT A PRETTY COLD NIGHT OVER THE INTERIOR WEST AND HAVE TEMPERATURES FALLING INTO THE TEENS BELOW ZERO. AS THIS OCCURS...THE WINDS WILL REALLY BE DIMINISHING AND EXPECT THAT TO KEEP WIND CHILLS IN CHECK FOR LATE WEDNESDAY NIGHT AND EARLY THURSDAY MORNING. WILL CONTINUE TO MENTION IN THE HWO DUE TO THE COLD FACTOR...BUT WITH WINDS LIKELY BEING BELOW 10MPH WE SHOULDN/T NEED A WIND CHILL ADVISORY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1256 PM EST MON FEB 2 2015 INCREASING MOISTURE LATE TONIGHT WITH THE ARRIVAL OF A SFC TROUGH FROM NW OF LAKE SUPERIOR WILL ALLOW FOR MVFR CONDITIONS TO RETURN AT BOTH KIWD AND KSAW WITH SOME LIGHT LES EXPECTED AT KIWD. AT KCMX...MVFR CIGS SHOULD PERSIST THROUGH THE FCST PERIOD. OCNL IFR VSBY IS EXPECTED THROUGH MID AFTERNOON UNTIL WINDS BACK ENOUGH TO THE SW TO PUSH THE LES BANDS TO THE NORTH. HOWEVER...LATE THIS EVENING INTO THE OVERNIGHT HOURS...EXPECT IFR VSBYS TO RETURN AS A DOMINANT LES BAND IS LIKELY TO DEVELOP AND SLOWLY SAG TO THE SOUTH ACROSS THE KEWEENAW PENINSULA. VSBYS SHOULD IMPROVE TO MVFR LATE TONIGHT AS WINDS SHIFT MORE NW AND THE DOMINANT LES BAND MOVES SOUTH OF THE AREA. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 525 AM EST MON FEB 2 2015 NORTHEAST WINDS BECOME WEST AHEAD OF APPROACHING TROUGH TODAY... THEN TURN TO THE NORTHWEST BEHIND THE TROUGH LATE TONIGHT AND TUESDAY. WEST WIND GUSTS OVER THE ERN HALF OF LAKE MAY BRIEFLY APPROACH GALE FORCE THIS EVENING...OTHER EXPECT WINDS AT OR BLO 30 KTS. HEAVY FREEZING SPRAY IS EXPECTED OVER PORTIONS OF THE WRN LAKE THIS AFTERNOON INTO THIS EVENING AND ERN LK SUPERIOR TONIGHT. STRONG COLD FRONT MOVES ACROSS LK SUPERIOR TUESDAY NIGHT INTO EARLY WEDNESDAY MORNING. NW WINDS COULD REACH LOW-END GALES ON WEDNESDAY. HEAVY FREEZING SPRAY IS EXPECTED DURING THIS TIME...ESPECIALLY FOR EAST HALF OF LK SUPERIOR. WINDS BACK SW ON THURSDAY AHEAD OF ANOTHER TROUGH THAT CROSSES ON LATE FRIDAY...THEN BECOME NORTHERLY BEHIND THE TROUGH INTO NEXT WEEKEND. WINDS SHOULD STAY AT OR BLO 30 KTS. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... LAKE EFFECT SNOW ADVISORY FROM 9 PM THIS EVENING TO 7 AM EST TUESDAY FOR MIZ003. LAKE EFFECT SNOW ADVISORY UNTIL 7 AM EST TUESDAY FOR MIZ001. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 6 AM EST TUESDAY FOR LSZ266- 267. HEAVY FREEZING SPRAY WARNING UNTIL 11 PM EST THIS EVENING FOR LSZ263-264. LAKE MICHIGAN... NONE. && $$ SHORT TERM...VOSS LONG TERM...SRF AVIATION...JLB MARINE...VOSS
AREA FORECAST DISCUSSION
NWS GLASGOW MT
324 PM MST MON FEB 2 2015 .SHORT TERM...FOR NORTHEAST MONTANA...TONIGHT THROUGH WEDNESDAY... FORECAST CHALLENGE IN THE SHORT TERM FORECAST PERIOD DEALS WITH THE EFFECTS FROM THE NEXT ACCUMULATING SNOWFALL EXPECTED LATER TONIGHT THROUGH TUESDAY ACROSS NORTHEAST MONTANA. MODELS SEEM TO BE IN GENERAL GOOD AGREEMENT WITH TIMING OF PRECIP...BUT SOME OF THE SMALLER-SCALE ISSUES WHICH MAY RESULT IN LESS FORECAST CONFIDENCE ARE EXACTLY WHERE SOME OF THE HEAVIER SNOW BANDS SET UP. COULD BE THE DIFFERENCE BETWEEN 1 OR 3 INCHES OF SNOW FOR MANY LOCATIONS. FOR EXAMPLE...00Z TO 06Z TONIGHT GFS AND NAM SHOW A NORTHERN ZONES BAND OF SNOW AND A SW ZONES BAND OF MIXED PRECIP. THE EC ON THE OTHER HAND IS MUCH WEAKER AND THE HRRR PLACES A BAND OF SNOW OVER THE CENTRAL CWA. FROM 06Z TO 12Z...GFS PAINTS A HEFTY WIDESPREAD ALMOST MODERATE SNOWFALL ACROSS MOST OF OUR CENTRAL CWA WHILE THE EC KEEPS THE HEAVIER SNOW OVER OUR FAR EASTERN AND SW ZONES. AFTER TUESDAY MORNING...MOST OF THE HEAVIER SNOWFALL WILL HAVE EASED TO MORE SCATTERED LIGHT SNOW SHOWERS WHICH WILL LIKELY LINGER THROUGH THE REMAINDER OF THE DAY. MODELS ARE ALSO INDICATING A GOOD CHANCE THAT SKIES WILL QUICKLY AND EFFECTIVELY CLEAR FROM NORTH TO SOUTH FOR TUESDAY NIGHT THROUGH WEDNESDAY MORNING. WITH A FRESH SNOW PACK...DECIDED TO DROP LOW TEMPERATURES FOR WEDNESDAY MORNING QUITE A BIT BELOW GUIDANCE GIVEN THE STRONGER THAN USUALLY EXPECTED RADIATIONAL COOLING. WINDS THROUGHOUT ARE EXPECTED TO BE OF MINIMAL IMPACT IF ANY AT ALL. BMICKELSON .LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY... UPDATE...GOING FORECAST IN OVERALL GOOD SHAPE. BIGGEST CHANGES MADE...BASED OFF THE 12Z EXTENDED MODELS...WAS TO GO CONSERVATIVE WITH THE WARM UP FOR LATE INTO THE WEEK INTO THE WEEKEND. CURRENT THINKING IS THAT WITH RECENT SNOW COVER...WARMING WILL BE HINDERED BY A LOW LEVEL INVERSION. THUS TRENDED DOWN TEMPS ACROSS THE NORTHEAST THROUGH THE AFOREMENTIONED PERIOD. ALSO TRENDED UP POPS FOR EXPECTED MIXED PRECIP THURSDAY NIGHT THROUGH SATURDAY NIGHT. GILCHRIST PREVIOUS DISCUSSION...MILD WEATHER RETURNS TO MONTANA FOR THE END OF THE WEEK WITH THE HUDSON BAY LOW WEAKENING AND PACIFIC UPPER RIDGE PUSHING INTO THE NORTHERN ROCKIES. WITH THE OPENING UP OF FLOW OFF THE PACIFIC INSTEAD OF OUT OF THE ARCTIC...WARM AIR WILL SPREAD ACROSS THE DIVIDE SENDING TEMPERATURES BACK ABOVE NORMAL. NEW SNOW COVER WILL SLOW THE WARMING SLIGHTLY BUT DOWNSLOPE WINDS WILL AID THE MIXING. SEVERAL SHORTWAVES MOVE ACROSS THE TOP OF THE RIDGE...WITH THE MOST SUBSTANTIAL ONE FORECAST FOR FRIDAY INTO SATURDAY ALTHOUGH MODEL SPREAD LARGE ENOUGH FOR UNCERTAINTY ON WHEN DURING THE WEEKEND ANY PRECIPITATION WILL OCCUR. TEMPERATURES PROFILES SUGGEST A MIX OF PRECIP TYPES POSSIBLE WITH THE CRITICAL THERMAL BOUNDARY LINGERING OVER NORTHEAST MONTANA. EBERT && .AVIATION... SOME MVFR CEILINGS MAY LINGER A BIT TODAY BEFORE ANOTHER ROUND OF SNOW MOVES INTO THE REGION TONIGHT WITH A RETURN TO IFR CONDITIONS EXPECTED. SOME LOCATIONS MAY EXPERIENCE BRIEF LIFR CONDITIONS OR AIRPORT MINIMUMS IN THE HEAVIER SNOW BANDS DURING THE OVERNIGHT OR EARLY TUESDAY MORNING HOURS. BMICKELSON && .GLASGOW WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 10 PM THIS EVENING TO 5 PM MST TUESDAY FOR CENTRAL AND SOUTHEAST PHILLIPS...CENTRAL AND SOUTHERN VALLEY...DANIELS...DAWSON...EASTERN ROOSEVELT... GARFIELD...MCCONE...NORTHERN PHILLIPS...NORTHERN VALLEY... RICHLAND...SOUTHWEST PHILLIPS...WESTERN ROOSEVELT. && $$ WEATHER.GOV/GLASGOW
AREA FORECAST DISCUSSION...UPDATED
NWS BILLINGS MT
952 AM MST MON FEB 2 2015 .UPDATE... SNOW SHOWER ACTIVITY HAS RAPIDLY ENDED ON THE GLASGOW RADAR DURING THE LAST HOUR OR SO...AND EXTRAPOLATING THAT TREND DOWNSTREAM INTO SOUTHEASTERN MT SUGGESTS OUR FORECAST FOR SNOW SHOWERS ENDING BY ABOUT NOON IS ON TRACK. THE SHORTWAVE TROUGH RESPONSIBLE FOR THAT ACTIVITY IS MOVING A BIT FASTER THAN EXPECTED THOUGH AND THAT HAS ALLOWED COLD AIR ADVECTION TO ALREADY BEGIN AND A SHALLOW LOW- LEVEL FRONTAL ZONE TO PUSH WEST ALL THE WAY TO BILLINGS...WHERE WINDS HAVE TURNED EASTERLY THIS MORNING. AS A RESULT...WE ACTUALLY LOWERED HIGHS A BIT TODAY FROM BILLINGS EASTWARD INTO SOUTHEASTERN MT USING THE 12 UTC GFS AND NAM MOS AND RECENT HRRR RUNS. SCHULTZ PREVIOUS UPDATE...ISSUED AT 800 AM MST MON FEB 2 2015... WE UPDATED THE FORECAST TO INCREASE SNOW SHOWER COVERAGE UP TO THE LIKELY CATEGORY WITH 60 TO 70 PERCENT POPS IN SOUTHEASTERN MT THIS MORNING. THAT WAS IN RESPONSE TO RECENT RADAR AND OBSERVATIONAL TRENDS. ACCUMULATIONS WILL STILL BE LIGHT...AND THE SNOW LOOKS TO BE MORE SHOWERY IN NATURE THAN CONTINUOUS...WHICH IS WHY WE CHOSE TO KEEP POPS CAPPED AROUND 70 PERCENT EVEN THOUGH IT IS SNOWING AT MILES CITY AND BAKER AS OF 15 UTC. SCHULTZ && .SHORT TERM...VALID FOR TDY AND TUE... SHORTWAVE MOVING FROM ALBERTA INTO NORTHEAST MONTANA HAS ALLOWED A WARM FRONT TO MOVE ACROSS THE AREA AND TEMPERATURES HAVE BEEN RISING OR STEADY OVERNIGHT. AS THIS ENERGY DIVES INTO THE DAKOTAS IT WILL LEAVE A SURFACE BOUNDARY BETWEEN COOLER AIR OVER NORTHEAST MONTANA AND AN AREA OVER CENTRAL MONTANA WHERE FLOW ALOFT IS MIXING DOWN CREATING DOWNSLOPE. AREAS ALONG AND NORTHEAST OF THIS BOUNDARY WILL SEE SOME PRECIPITATION THIS MORNING BUT WILL DRY THIS AFTERNOON AS HEIGHT RISES BRING SOME SUBSIDENCE. TEMPERATURES IN WESTERN AND CENTRAL ZONES WILL REBOUND TODAY INTO THE 40S WITH WINDS ALONG THE FOOTHILLS BUT EXPECT WINDS TO LIGHTEN UP A BIT FROM THEIR PEAKS EARLY THIS MORNING. STRONGER SURGE OF ENERGY MOVES INTO THE AREA TONIGHT BUT THE SURFACE PATTERN CHANGES LITTLE SO THE BEST CHANCE OF PRECIPITATION WILL REMAIN NORTH AND EAST OF THE SURFACE TROUGH WHICH WILL LAY ALONG A HARLOWTON TO GILLETTE AXIS. IT WILL REMAIN BREEZY OVER THE WESTERN ZONES BUT ENOUGH ENERGY GOING ACROSS SOUTHERN IDAHO AND WESTERN WYOMING TO LIMIT THE STRENGTH OF PRESSURE GRADIENTS. GIVEN THE STATIONARY NATURE OF THE BOUNDARY OVERNIGHT EXPECT PRECIPITATION AMOUNTS OVER NORTHERN PORTIONS OF SOUTHEAST MONTANA TO BE LIGHT. TUESDAY THE JET ENERGY STRENGTHENS AND SHIFTS EASTWARD ACROSS THE STATE WITH ANOTHER JET PUSHING INTO THE PACIFIC NORTHWEST. SUBSIDENT ZONE OF THE FIRST JET OVER NORTHEAST MONTANA ALLOWS SURFACE HIGH PRESSURE TO BUILD AND BEGIN TO SHIFT SOUTHWARD WHICH PUSHES THE SURFACE BOUNDARY SOUTHWARD AND ALLOWS SOME FRONTOGENESIS TO OCCUR OVER SOUTH CENTRAL MONTANA. THIS PROCESS WILL ALLOW SNOW TO MOVE INTO THE BILLINGS AREA LATER ON TUESDAY WITH THE BEST CHANCE FOR SNOW TUESDAY NIGHT. TUESDAY EVENING THE FRONT CONTINUES TO MOVE SOUTH AND SNOW WILL BEGIN OVER THE FOOTHILLS AND HAVE THE SUPPORT OF UPSLOPE. HOWEVER...BUFKIT SOUNDINGS REFLECT THE PRESENCE OF CONFLUENT FLOW AT 500MB SO LIFT IS NOT VERY DEEP AND SHORT LIVED ONCE THE BOUNDARY KEEPS MOVING SOUTH. SHOULD SEE A BAND OF 2 TO 3 INCH SNOW ACROSS MOST OF THE AREA WITH HIGHER AMOUNTS OVER THE FOOTHILLS BEFORE SNOW BEGINS TO TAPER OFF LATE TUESDAY NIGHT. CLEARING LATE TUESDAY NIGHT WILL SUPPORT COLDER TEMPERATURES ESPECIALLY WITH FRESH SNOW COVER. BORSUM .LONG TERM...VALID FOR WED...THU...FRI...SAT...SUN... THE EXTENDED FORECAST PERIOD CONTINUES TO LOOK DRY AND UNSEASONABLY WARM FOR THE MOST PART..WITH UPPER LEVEL RIDGE IN CONTROL OVER THE REGION. WEDNESDAY LOOKS LIKE IT WILL BE THE COLDEST DAY...AS A SHORTWAVE TROUGH EXITS THE REGION. COLD AIR REMAINS IN PLACE...WITH 850MB TEMPS FROM -12C TO -18C OVER THE CWA. WARM AIR ADVECTION IS PROGGED TO BEGIN TO PUSH COLD AIR OUT WEDNESDAY AFTERNOON...ALLOWING HIGHS TO REACH LOW 30S. MODELS STILL DIFFER ON HOW LONG SNOW SHOWERS LINGER INTO WEDNESDAY...BUT SHOULD SEE IMPROVING CONDITIONS FROM NORTH TO SOUTH THROUGH THE MORNING. RIDGING BEGINS BUILDING INTO THE REGION WEDNESDAY NIGHT...BEGINNING THE WARMING TREND THURSDAY. THE BROAD RIDGE REMAINS IN PLACE THROUGH THE REMAINDER OF THE PERIOD. ALTHOUGH SEVERAL RELATIVELY WEAK SHORTWAVES RIDE UP AND OVER THE RIDGE...WITH PLENTY OF PACIFIC MOISTURE...THEY APPEAR TO BE OF LITTLE CONSEQUENCE FOR THE PLAINS...WITH PERSISTENT DOWNSLOPE FLOW THROUGH THE PERIOD. THEREFORE THE MOUNTAINS WILL BE PRIMARY FOCUS FOR ANY PRECIP. THAT BEING SAID...THE STRONGEST SHORTWAVE IS STILL PROGGED TO IMPACT THE REGION LATE FRIDAY...AND INTO SATURDAY. THIS SHOULD SPREAD SOME SHOWER ACTIVITY INTO THE PLAINS...BUT MAINLY EAST OF KBIL...AS DOWNSLOPE FLOW PERSISTS TO LIMIT ANY DEVELOP IN WESTERN PLAINS AND FOOTHILLS REGIONS. WINDS WILL BEGIN TO INCREASE FROM THURSDAY NIGHT ONWARD...ESPECIALLY FROM LIVINGSTON TO NYE. GUIDANCE CURRENTLY SEEMS TO POINT TO STRONGEST WINDS FROM SATURDAY INTO SUNDAY ACROSS THE WEST...WHICH WOULD CORRESPOND WITH STRONGER SHORTWAVE EXITING THAT AREA. AAG && .AVIATION... A COLD FRONT WILL BRING SNOW TO AREAS E OF KBIL THIS MORNING WITH MVFR TO IFR CONDITIONS POSSIBLE...BUT EXPECT A RETURN OF VFR CONDITIONS TO THE AREA THIS AFTERNOON. MORE SNOW WILL MOVE INTO THE NORTHEAST ROUTES...INCLUDING KBHK AND KMLS...LATER TONIGHT AND EARLY TUESDAY. MVFR TO IFR CONDITIONS WILL BE POSSIBLE IN SNOW. EXPECT AREAS OF MOUNTAIN OBSCURATION THROUGH THE PERIOD. LOW-LEVEL WIND SHEAR IS EXPECTED TO PERSIST AT KBIL AND KSHR THROUGH THIS MORNING. AAG/CHAMBERS && .PRELIMINARY POINT TEMP/POPS... TDY TUE WED THU FRI SAT SUN ------------------------------------------------------- BIL 042 029/040 013/031 028/051 037/060 041/060 038/055 1/B 13/W 72/J 10/B 01/N 11/N 11/N LVM 049 034/047 019/039 031/055 038/061 044/059 038/058 1/N 22/W 74/W 22/W 11/N 23/W 11/N HDN 039 024/036 007/027 020/050 030/056 038/057 032/055 2/J 24/J 62/J 10/B 01/B 11/N 11/B MLS 028 017/026 003/023 014/045 027/053 037/056 032/054 6/J 56/J 41/B 11/B 01/B 12/W 11/B 4BQ 037 022/036 009/027 021/050 030/059 040/058 034/055 4/J 24/J 51/B 10/B 01/B 12/W 11/B BHK 026 013/024 901/020 014/044 026/048 033/049 032/049 7/J 44/J 21/B 10/B 11/B 12/W 11/B SHR 041 024/042 013/029 022/050 029/061 035/058 029/054 1/B 12/W 73/J 10/B 00/B 11/B 11/B && .BYZ WATCHES/WARNINGS/ADVISORIES... MT...NONE. WY...NONE. && $$ WEATHER.GOV/BILLINGS
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
208 PM EST MON FEB 2 2015 .SYNOPSIS... BITTERLY COLD AIR WILL MOVE INTO NY AND PA FOR TONIGHT. ANOTHER STORM SYSTEM WILL BRING SNOW TO THE REGION LATE WEDNESDAY, FOLLOWED BY EVEN COLDER AIR FOR THURSDAY AND FRIDAY. && .NEAR TERM /THROUGH TONIGHT/... 205 PM UPDATE... WE WILL DROP THE REMAINING WARNINGS SHORTLY, COINCIDENT WITH RAISING A NEW FLAG FOR WIND CHILL ADVISORIES OVER MUCH OF THE FA FOR OVERNIGHT. MOS GUIDANCE AND RUC/HRRR TEMPS GETTING COLDER AND COLDER FOR TONIGHT, PERHAPS CATCHING ON TO THE BITTERLY COLD TEMPERATURES OBSERVED OVER LOWER ONTARIO AND QUEBEC. OVERNIGHT MINS WILL RANGE FROM AROUND ZERO OVER THE SOUTH, TO -15F OVER NORTHEASTERN ONEIDA COUNTY. COMBINED WITH 6 TO 10 MPH WINDS, APPARENT TEMPERATURES PLUMMET TO -15F TO -20F. 1145 AM UPDATE... DROPPED ANOTHER BLOCK OF COUNTIES FROM THE WARNING. WILL HOLD ON TO THE WARNING OVER THE FAR EAST AND NORTH. A FEW MODERATE SNOW BANDS HAVE YET TO CLEAR OUR EASTERN COUNTIES, WHILE THE NORTH MAY STILL BE AFFECTED BY WEAKENING DEFORMATION ZONE ACTIVITY. WINDS WILL BECOME GUSTY THIS AFTERNOON, WITH FREQUENT GUSTS OF 20 TO 25 MPH AND OCCASIONAL GUSTS AROUND 30 MPH. 1040 AM UPDATE... WE HAVE DROPPED THE SOUTHWESTERN CORNER OF THE WARNING. RADAR SHOWS THAT THE STEADY PRECIPITATION HAS MOVED OUT OF THIS REGION, AND HRRR SUGGESTS THAT THE DEFORMATION ZONE ACTIVITY OVER WESTERN NY WILL LIFT ACROSS THE FINGER LAKES AND FIZZLE OUT THIS AFTERNOON. WE MAY DROP ANOTHER BLOCK OF COUNTIES IN THE NEXT 1-2 HOURS. HOWEVER, WE WILL ALLOW THE MODERATE BANDS MOVING THROUGH PORTIONS OF NORTHERN PA AND THE LOWER SUSQUEHANNA REGION TO CLEAR THE AREA FIRST. 430 AM UPDATE... AT 430 AM SFC LOW PRES WAS LOCATED OVER WESTERN PA. LOCAL RADARS/OBS SHOW LIGHT TO MODERATE SNOW ACROSS THE REGION WITH ANOTHER AREA OF STRONG RETURNS HEADING TOWARD THE REGION FROM WRN PA. THE HEAVIEST SNOWFALL RATES WILL CONTINUE THROUGH MID MORNING THEN THE ACTIVITY WILL GRADUALLY WEAKEN AS JET DYNAMICS AND ISENTROPIC LIFT MOVES EAST OF FA. THE SFC LOW WILL TRACK EAST ACROSS NORTH CENTRAL PA THEN OFF THE NJ COAST BY MIDDAY. A BRIEF PERIOD FGEN FORCING IN THE WESTERN CATSKILLS MAY KEEP OCCASIONAL HEAVY SNOW HERE THROUGH EARLY AFTERNOON. MODEL CONSENSUS CONTINUES TO INDICATE THE SNOW WILL MIX WITH SLEET/FZRA BRIEFLY THIS MORNING ACROSS PARTS OF NE PA. OBS IN THE STATE COLLEGE AREA ARE ALREADY INDICATING THIS TYPE OF PRECIP. THE ACTIVITY WILL CHANGE BACK TO SNOW BY MID/LATE MORNING. TOTAL SNOW ACCUMS IN GENERAL WILL RANGE FROM 8 TO 12 INCHES ACROSS CENTRAL NY AND NRN TIER OF PA AND 5 TO 8 IN THE FAR SE WITH SOME LIGHT ICING. ONCE THE SYSTEM LIFTS NORTHEAST INTO COASTAL NEW ENGLAND THIS AFTERNOON STRONG NW WINDS WILL CAUSE BLOWING AND DRIFTING SNOW ALONG WITH FALLING TEMPS. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY/... TONIGHT...VERY COLD AIRMASS WILL BE USHERED BACK INTO THE REGION THIS EVENING UNDER NW FLOW. PARTS OF THE ERN CWA MAY REQUIRE A WIND CHILL ADVISORY OVERNIGHT BUT WILL LET NEXT SHIFT CONSIDER THIS FLAG. NW FLOW WILL GRADUALLY BACK OVERNIGHT BRINGING SCATTERED LAKE EFFECT SNOW SHOWERS FROM THE FINGER LAKES REGION NORTH ACROSS THE SYR AREA INTO THE SOUTHERN TUG HILL BY DAYBREAK. LOW INVERSION, SFC RIDGING AND VERY DRY AIRMASS WILL RESULT IN ONLY MINOR ACCUMS. REST OF AREA WILL BE DRY UNDER PARTLY CLOUDY SKIES WITH MIN TEMPS GENERALLY ZERO TO 10 BELOW. TUESDAY...SFC HIGH PRES IN THE MID ATLANTIC AND A SFC TROF DROPPING INTO THE UPPER GREAT LAKES WILL PRODUCE A SOUTHWEST FLOW. A PRECIP FREE DAY IS EXPECTED ALONG WITH PARTLY SUNNY TO MOSTLY CLOUDY SKIES. MAX TEMPS WILL GENERALLY BE IN THE TEENS WITH THE NORMALLY WARMER AREAS IN THE FINGER LAKES AND CENTRAL SRN TIER APPROACHING 20. TUESDAY NIGHT/WEDNESDAY...A WEAK CLIPPER TYPE SYSTEM WILL TRACK FROM THE MID WEST ACROSS LOWER MICHIGAN TO SOUTHERN QUEBEC BY WED EVENING. THIS FEATURE WILL BEING SOME LIGHT SNOW MAINLY TO CENTRAL NY PRIMARILY LATE TUE NIGHT THROUGH WED. WILL CONTINUE TO ADVERTISE LIKELY POPS OVER THE NRN CWA AND CHC ELSEWHERE. SNOW ACCUMS OF 1 TO 3 INCHES ARE POSSIBLE. ON WED TEMPS WILL MODERATE TO AROUND THE FREEZING MARK AHEAD OF THE APPROACHING SFC TROF. WEDNESDAY NIGHT...AS THIS SFC LOW CONTINUES LIFTING OFF TO THE NE THE TRAILING COLD FRONT WILL DROP THROUGH THE REGION BRINGING THE POTENTIAL FOR MORE SNOW SHOWERS. BEHIND THIS BOUNDARY ANOTHER PUSH OF ARCTIC AIR WILL MOVE THROUGH THE NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 2 AM UPDATE... LITTLE CHANGE. POPULATED WITH CURRENT WPC GUIDANCE. WEAK SYSTEM CENTERED SOUTH OF REGION WILL BRING LIGHT SNOW. LITTLE TO ADD TO PREVIOUS DISCUSSION. PREVIOUS DISCUSSION FROM SUNDAY AFTERNOON... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /19Z MONDAY THROUGH SATURDAY/... 18Z UPDATE... STORM SYSTEM IS STILL FINISHING UP OVER THE TERMINALS THIS AFTERNOON. ARCTIC FRONT NOW IN PROGRESS OF SWITCHING WINDS TO A GUSTY NNW /PEAK GUSTS 24-29 KTS KITH-KBGM-KELM-KAVP THIS AFTERNOON/...AS STEADY SNOW IS REPLACED BY SNOW SHOWERS AND BLOWING SNOW. THIS WILL RESULT IN MVFR TO IFR VIS AND FUEL ALT REQ MVFR CIG /IFR CIG AT TIMES KBGM-KITH/. TONIGHT...VERY COLD YET DRY AIR SHOULD ALLOW FOR IMPROVEMENT...YET WITH FLOW DOWN CAYUGA LAKE...IFR -SN WILL PERSIST INTO EVENING. FLOW TO BACK MORE WESTERLY OR EVEN WSW INTO TUESDAY MORNING...ALLOWING ANY REMAINING CIGS TO SCT OUT FOR KBGM-KITH-KAVP-KELM...BUT KSYR-KRME WILL BECOME PRONE TO LAKE EFFECT SNOW SHOWERS. OUTLOOK... TUE AFTN-EVE...MAINLY VFR. LATE TUE NGT/WED/THU...POSSIBLE RESTRICTIONS FROM SNOW SHOWERS. FRI...VFR. SAT...POSSIBLE RESTRICTIONS FROM SNOW SHOWERS...MAINLY NY TERMINALS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 016>018-036-037-045-046-057-062. && $$ SYNOPSIS...DJP NEAR TERM...DJP/RRM SHORT TERM...RRM LONG TERM...DJP/TAC AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1253 PM EST MON FEB 2 2015 .SYNOPSIS... AFTER THE WINTER STORM EXITS THE REGION TODAY, BITTERLY COLD AIR WILL MOVE INTO NY AND PA FOR TONIGHT. A WEAKER STORM WILL BRING LIGHT SNOW TO THE REGION LATE WEDNESDAY, FOLLOWED BY EVEN COLDER AIR FOR THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 1145 AM UPDATE... DROPPED ANOTHER BLOCK OF COUNTIES FROM THE WARNING. WILL HOLD ON TO THE WARNING OVER THE FAR EAST AND NORTH. A FEW MODERATE SNOW BANDS HAVE YET TO CLEAR OUR EASTERN COUNTIES, WHILE THE NORTH MAY STILL BE AFFECTED BY WEAKENING DEFORMATION ZONE ACTIVITY. WINDS WILL BECOME GUSTY THIS AFTERNOON, WITH FREQUENT GUSTS OF 20 TO 25 MPH AND OCCASIONAL GUSTS AROUND 30 MPH. 1040 AM UPDATE... WE HAVE DROPPED THE SOUTHWESTERN CORNER OF THE WARNING. RADAR SHOWS THAT THE STEADY PRECIPITATION HAS MOVED OUT OF THIS REGION, AND HRRR SUGGESTS THAT THE DEFORMATION ZONE ACTIVITY OVER WESTERN NY WILL LIFT ACROSS THE FINGER LAKES AND FIZZLE OUT THIS AFTERNOON. WE MAY DROP ANOTHER BLOCK OF COUNTIES IN THE NEXT 1-2 HOURS. HOWEVER, WE WILL ALLOW THE MODERATE BANDS MOVING THROUGH PORTIONS OF NORTHERN PA AND THE LOWER SUSQUEHANNA REGION TO CLEAR THE AREA FIRST. 430 AM UPDATE... AT 430 AM SFC LOW PRES WAS LOCATED OVER WESTERN PA. LOCAL RADARS/OBS SHOW LIGHT TO MODERATE SNOW ACROSS THE REGION WITH ANOTHER AREA OF STRONG RETURNS HEADING TOWARD THE REGION FROM WRN PA. THE HEAVIEST SNOWFALL RATES WILL CONTINUE THROUGH MID MORNING THEN THE ACTIVITY WILL GRADUALLY WEAKEN AS JET DYNAMICS AND ISENTROPIC LIFT MOVES EAST OF FA. THE SFC LOW WILL TRACK EAST ACROSS NORTH CENTRAL PA THEN OFF THE NJ COAST BY MIDDAY. A BRIEF PERIOD FGEN FORCING IN THE WESTERN CATSKILLS MAY KEEP OCCASIONAL HEAVY SNOW HERE THROUGH EARLY AFTERNOON. MODEL CONSENSUS CONTINUES TO INDICATE THE SNOW WILL MIX WITH SLEET/FZRA BRIEFLY THIS MORNING ACROSS PARTS OF NE PA. OBS IN THE STATE COLLEGE AREA ARE ALREADY INDICATING THIS TYPE OF PRECIP. THE ACTIVITY WILL CHANGE BACK TO SNOW BY MID/LATE MORNING. TOTAL SNOW ACCUMS IN GENERAL WILL RANGE FROM 8 TO 12 INCHES ACROSS CENTRAL NY AND NRN TIER OF PA AND 5 TO 8 IN THE FAR SE WITH SOME LIGHT ICING. ONCE THE SYSTEM LIFTS NORTHEAST INTO COASTAL NEW ENGLAND THIS AFTERNOON STRONG NW WINDS WILL CAUSE BLOWING AND DRIFTING SNOW ALONG WITH FALLING TEMPS. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY/... TONIGHT...VERY COLD AIRMASS WILL BE USHERED BACK INTO THE REGION THIS EVENING UNDER NW FLOW. PARTS OF THE ERN CWA MAY REQUIRE A WIND CHILL ADVISORY OVERNIGHT BUT WILL LET NEXT SHIFT CONSIDER THIS FLAG. NW FLOW WILL GRADUALLY BACK OVERNIGHT BRINGING SCATTERED LAKE EFFECT SNOW SHOWERS FROM THE FINGER LAKES REGION NORTH ACROSS THE SYR AREA INTO THE SOUTHERN TUG HILL BY DAYBREAK. LOW INVERSION, SFC RIDGING AND VERY DRY AIRMASS WILL RESULT IN ONLY MINOR ACCUMS. REST OF AREA WILL BE DRY UNDER PARTLY CLOUDY SKIES WITH MIN TEMPS GENERALLY ZERO TO 10 BELOW. TUESDAY...SFC HIGH PRES IN THE MID ATLANTIC AND A SFC TROF DROPPING INTO THE UPPER GREAT LAKES WILL PRODUCE A SOUTHWEST FLOW. A PRECIP FREE DAY IS EXPECTED ALONG WITH PARTLY SUNNY TO MOSTLY CLOUDY SKIES. MAX TEMPS WILL GENERALLY BE IN THE TEENS WITH THE NORMALLY WARMER AREAS IN THE FINGER LAKES AND CENTRAL SRN TIER APPROACHING 20. TUESDAY NIGHT/WEDNESDAY...A WEAK CLIPPER TYPE SYSTEM WILL TRACK FROM THE MID WEST ACROSS LOWER MICHIGAN TO SOUTHERN QUEBEC BY WED EVENING. THIS FEATURE WILL BEING SOME LIGHT SNOW MAINLY TO CENTRAL NY PRIMARILY LATE TUE NIGHT THROUGH WED. WILL CONTINUE TO ADVERTISE LIKELY POPS OVER THE NRN CWA AND CHC ELSEWHERE. SNOW ACCUMS OF 1 TO 3 INCHES ARE POSSIBLE. ON WED TEMPS WILL MODERATE TO AROUND THE FREEZING MARK AHEAD OF THE APPROACHING SFC TROF. WEDNESDAY NIGHT...AS THIS SFC LOW CONTINUES LIFTING OFF TO THE NE THE TRAILING COLD FRONT WILL DROP THROUGH THE REGION BRINGING THE POTENTIAL FOR MORE SNOW SHOWERS. BEHIND THIS BOUNDARY ANOTHER PUSH OF ARCTIC AIR WILL MOVE THROUGH THE NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 2 AM UPDATE... LITTLE CHANGE. POPULATED WITH CURRENT WPC GUIDANCE. WEAK SYSTEM CENTERED SOUTH OF REGION WILL BRING LIGHT SNOW. LITTLE TO ADD TO PREVIOUS DISCUSSION. PREVIOUS DISCUSSION FROM SUNDAY AFTERNOON... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... 18Z UPDATE... STORM SYSTEM IS STILL FINISHING UP OVER THE TERMINALS THIS AFTERNOON. ARCTIC FRONT NOW IN PROGRESS OF SWITCHING WINDS TO A GUSTY NNW /PEAK GUSTS 24-29 KTS KITH-KBGM-KELM-KAVP THIS AFTERNOON/...AS STEADY SNOW IS REPLACED BY SNOW SHOWERS AND BLOWING SNOW. THIS WILL RESULT IN MVFR TO IFR VIS AND FUEL ALT REQ MVFR CIG /IFR CIG AT TIMES KBGM-KITH/. TONIGHT...VERY COLD YET DRY AIR SHOULD ALLOW FOR IMPROVEMENT...YET WITH FLOW DOWN CAYUGA LAKE...IFR -SN WILL PERSIST INTO EVENING. FLOW TO BACK MORE WESTERLY OR EVEN WSW INTO TUESDAY MORNING...ALLOWING ANY REMAINING CIGS TO SCT OUT FOR KBGM-KITH-KAVP-KELM...BUT KSYR-KRME WILL BECOME PRONE TO LAKE EFFECT SNOW SHOWERS. OUTLOOK... TUE AFTN-EVE...MAINLY VFR. LATE TUE NGT/WED/THU...POSSIBLE RESTRICTIONS FROM SNOW SHOWERS. FRI...VFR. SAT...POSSIBLE RESTRICTIONS FROM SNOW SHOWERS...MAINLY NY TERMINALS. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 016>018-036-037-045-046-057-062. && $$ SYNOPSIS...DJP NEAR TERM...DJP/RRM SHORT TERM...RRM LONG TERM...DJP/TAC AVIATION...MDP
AREA FORECAST DISCUSSION
NWS BINGHAMTON NY
1143 AM EST MON FEB 2 2015 .SYNOPSIS... AFTER THE WINTER STORM EXITS THE REGION TODAY, BITTERLY COLD AIR WILL MOVE INTO NY AND PA FOR TONIGHT. A WEAKER STORM WILL BRING LIGHT SNOW TO THE REGION LATE WEDNESDAY, FOLLOWED BY EVEN COLDER AIR FOR THURSDAY AND FRIDAY. && .NEAR TERM /UNTIL 8 PM THIS EVENING/... 1145 AM UPDATE... DROPPED ANOTHER BLOCK OF COUNTIES FROM THE WARNING. WILL HOLD ON TO THE WARNING OVER THE FAR EAST AND NORTH. A FEW MODERATE SNOW BANDS HAVE YET TO CLEAR OUR EASTERN COUNTIES, WHILE THE NORTH MAY STILL BE AFFECTED BY WEAKNENING DEFORMATION ZONE ACTIVITY. WINDS WILL BECOME GUSTY THIS AFTERNOON, WITH FREQUENT GUSTS OF 20 TO 25 MPH AND OCCASIONAL GUSTS AROUND 30 MPH. 1040 AM UPDATE... WE HAVE DROPPED THE SOUTHWESTERN CORNER OF THE WARNING. RADAR SHOWS THAT THE STEADY PRECIPITATION HAS MOVED OUT OF THIS REGION, AND HRRR SUGGESTS THAT THE DEFORMATION ZONE ACTIVITY OVER WESTERN NY WILL LIFT ACROSS THE FINGER LAKES AND FIZZLE OUT THIS AFTERNOON. WE MAY DROP ANOTHER BLOCK OF COUNTIES IN THE NEXT 1-2 HOURS. HOWEVER, WE WILL ALLOW THE MODERATE BANDS MOVING THROUGH PORTIONS OF NORTHERN PA AND THE LOWER SUSQUEHANNA REGION TO CLEAR THE AREA FIRST. 430 AM UPDATE... AT 430 AM SFC LOW PRES WAS LOCATED OVER WESTERN PA. LOCAL RADARS/OBS SHOW LIGHT TO MODERATE SNOW ACROSS THE REGION WITH ANOTHER AREA OF STRONG RETURNS HEADING TOWARD THE REGION FROM WRN PA. THE HEAVIEST SNOWFALL RATES WILL CONTINUE THROUGH MID MORNING THEN THE ACTIVITY WILL GRADUALLY WEAKEN AS JET DYNAMICS AND ISENTROPIC LIFT MOVES EAST OF FA. THE SFC LOW WILL TRACK EAST ACROSS NORTH CENTRAL PA THEN OFF THE NJ COAST BY MIDDAY. A BRIEF PERIOD FGEN FORCING IN THE WESTERN CATSKILLS MAY KEEP OCCASIONAL HEAVY SNOW HERE THROUGH EARLY AFTERNOON. MODEL CONSENSUS CONTINUES TO INDICATE THE SNOW WILL MIX WITH SLEET/FZRA BRIEFLY THIS MORNING ACROSS PARTS OF NE PA. OBS IN THE STATE COLLEGE AREA ARE ALREADY INDICATING THIS TYPE OF PRECIP. THE ACTIVITY WILL CHANGE BACK TO SNOW BY MID/LATE MORNING. TOTAL SNOW ACCUMS IN GENERAL WILL RANGE FROM 8 TO 12 INCHES ACROSS CENTRAL NY AND NRN TIER OF PA AND 5 TO 8 IN THE FAR SE WITH SOME LIGHT ICING. ONCE THE SYSTEM LIFTS NORTHEAST INTO COASTAL NEW ENGLAND THIS AFTERNOON STRONG NW WINDS WILL CAUSE BLOWING AND DRIFTING SNOW ALONG WITH FALLING TEMPS. && .SHORT TERM /8 PM THIS EVENING THROUGH WEDNESDAY/... TONIGHT...VERY COLD AIRMASS WILL BE USHERED BACK INTO THE REGION THIS EVENING UNDER NW FLOW. PARTS OF THE ERN CWA MAY REQUIRE A WIND CHILL ADVISORY OVERNIGHT BUT WILL LET NEXT SHIFT CONSIDER THIS FLAG. NW FLOW WILL GRADUALLY BACK OVERNIGHT BRINGING SCATTERED LAKE EFFECT SNOW SHOWERS FROM THE FINGER LAKES REGION NORTH ACROSS THE SYR AREA INTO THE SOUTHERN TUG HILL BY DAYBREAK. LOW INVERSION, SFC RIDGING AND VERY DRY AIRMASS WILL RESULT IN ONLY MINOR ACCUMS. REST OF AREA WILL BE DRY UNDER PARTLY CLOUDY SKIES WITH MIN TEMPS GENERALLY ZERO TO 10 BELOW. TUESDAY...SFC HIGH PRES IN THE MID ATLANTIC AND A SFC TROF DROPPING INTO THE UPPER GREAT LAKES WILL PRODUCE A SOUTHWEST FLOW. A PRECIP FREE DAY IS EXPECTED ALONG WITH PARTLY SUNNY TO MOSTLY CLOUDY SKIES. MAX TEMPS WILL GENERALLY BE IN THE TEENS WITH THE NORMALLY WARMER AREAS IN THE FINGER LAKES AND CENTRAL SRN TIER APPROACHING 20. TUESDAY NIGHT/WEDNESDAY...A WEAK CLIPPER TYPE SYSTEM WILL TRACK FROM THE MID WEST ACROSS LOWER MICHIGAN TO SOUTHERN QUEBEC BY WED EVENING. THIS FEATURE WILL BEING SOME LIGHT SNOW MAINLY TO CENTRAL NY PRIMARILY LATE TUE NIGHT THROUGH WED. WILL CONTINUE TO ADVERTISE LIKELY POPS OVER THE NRN CWA AND CHC ELSEWHERE. SNOW ACCUMS OF 1 TO 3 INCHES ARE POSSIBLE. ON WED TEMPS WILL MODERATE TO AROUND THE FREEZING MARK AHEAD OF THE APPROACHING SFC TROF. WEDNESDAY NIGHT...AS THIS SFC LOW CONTINUES LIFTING OFF TO THE NE THE TRAILING COLD FRONT WILL DROP THROUGH THE REGION BRINGING THE POTENTIAL FOR MORE SNOW SHOWERS. BEHIND THIS BOUNDARY ANOTHER PUSH OF ARCTIC AIR WILL MOVE THROUGH THE NORTHEAST. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... 2 AM UPDATE... LITTLE CHANGE. POPULATED WITH CURRENT WPC GUIDANCE. WEAK SYSTEM CENTERED SOUTH OF REGION WILL BRING LIGHT SNOW. LITTLE TO ADD TO PREVIOUS DISCUSSION. PREVIOUS DISCUSSION FROM SUNDAY AFTERNOON... A LARGE SCALE TROF OVER THE NORTHEASTERN UNITED STATES WILL CONTINUE TO KEEP OUR TEMPERATURES WELL BELOW NORMAL. A WEAK DEPARTING CYCLONE WILL SLIDE EASTWARD WEDNESDAY NIGHT, BRINGING ADDITIONAL SNOW SHOWERS AND A SECOND SHOT OF ARCTIC AIR. THURSDAY APPEARS PARTICULARLY COLD. 925MB TEMPS ARE IN THE -17C T0 -20C RANGE ACCORDING TO THE ECMWF. THIS AIRMASS WILL YIELD MAXIMUMS IN THE SINGLE DIGITS TO LOW TEENS. FRIDAY MORNING LOOKS FRIGID, WITH WIDESPREAD -5F TO -15F TEMPERATURES FORECAST. THE RURAL VALLEYS WILL BE EVEN COLDER. SOME MODERATION IS POSSIBLE ON SATURDAY AS A SOUTHERN RIDGE EXPANDS INTO THE MID-ATLANTIC REGION. HOWEVER TEMPERATURES WILL REMAIN BELOW NORMAL. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... 1230 AM UPDATE... WIDESPREAD IFR VSBYS ACROSS THE TERMINALS. VSBYS UNDER 1SM BY 8Z THROUGH ABOUT 12Z/13Z. THE EXCEPTION WILL BE AT KAVP, WHERE MIXING WITH SLEET OR FREEZING RAIN WILL LIKELY IMPROVE VSBYS AFTER 08Z. WHILE NOT AS LOW AS NOW, IFR VSBYS WILL CONTINUE IN LIGHT SNOW ON THE BACKSIDE OF THE STORM THROUGH MIDDAY. THE SNOW TAPERS OFF BUT GUSTY WINDS COULD CAUSE BLOWING SNOW KEEPING VSBYS IFR AT TIMES. ALSO DURING THE AFTN THE LOW LEVEL FLOW GOES TO NW STARTING THE LAKE EFFECT AND ALSO WRAP AROUND. NY TERMINALS 2 TO 3 MILES. CIGS MOSTLY 1 TO 2K FT WILL DROP SOME THROUGH 14Z THEN SLOWLY IMPROVE. EXCEPTION MAY BE ITH AND BGM IN THE AFTN WITH THE LES. EAST WINDS 5 T0 10 KTS THIS MORNING. WINDS SHIFTING TO THE NORTHWEST 16 TO 19Z AT 10 KTS INCREASING TO 10 TO 15 WITH GUSTS TO 20-25 KTS. SLOWLY DIMINISHING AFTER 00Z. OUTLOOK... TONIGHT...IMPROVEMENT TO VFR FROM S TO N. TUE/TUE EVE...VFR. TUE OVERNIGHT/WED/THU...POSSIBLE RESTRICTIONS DUE TO SNOW SHOWERS. FRI...VFR. && .BGM WATCHES/WARNINGS/ADVISORIES... PA...NONE. NY...WINTER STORM WARNING UNTIL 4 PM EST THIS AFTERNOON FOR NYZ009- 016>018-036-037-045-046-057-062. && $$ SYNOPSIS...DJP NEAR TERM...DJP/RRM SHORT TERM...RRM LONG TERM...DJP/TAC AVIATION...TAC
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1255 PM EST MON FEB 2 2015 .SYNOPSIS... A STRONG COLD FRONT WILL MOVE EAST OF THE AREA AND OFFSHORE BY LATE THIS AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE REGION THIS EVENING THROUGH MIDWEEK. && .NEAR TERM /TODAY/... AS OF 1202 PM MONDAY... UPDATED: LARGER PRECIP SHIELD IS HEADING OUT OF THE CWA... SO WILL MAKE APPROPRIATE ADJUSTMENTS TO POPS TO ACCOUNT FOR THIS AS WELL AS THE BANDS OF SHOWERS ALONG AND JUST BEHIND THE FRONT. THE FRONT ITSELF IS DEPICTED NICELY ON VIS SATELLITE IMAGERY FROM AROUND ROANOKE RAPIDS TO THE CITY OF RALEIGH TO JUST NW OF WADESBORO. WE`RE STARTING TO GET SOME OF THE LARGER POST-FRONTAL NORTHWESTERLY GUSTS WITHIN THE STRENGTHENING COLD AIR ADVECTION... AS HIGH AS 28-30 KT... WITH A FEW STRONGER GUSTS AT WEST JEFFERSON IN THE LAST HR... SO WE STILL EXPECT NUMEROUS GUSTS IN THE 25-30 KT RANGE (AND SPORADICALLY STRONGER) THIS AFTERNOON... SO THE ADVISORY WILL BE LEFT AS IS. -GIH PREVIOUS DISCUSSION FOR THE REST OF TODAY: WILL LEAVE THE WIND ADVISORY IN EFFECT FOR THIS AFTERNOON... BASED ON ANTICIPATED IMPACTS... ALTHOUGH THERE IS SOME INDICATION THAT WE MAY NOT QUITE GET UP TO ADVISORY CRITERIA. LATEST SURFACE ANALYSIS SHOWS THE COLD FRONT HAVING MOVED THROUGH THE TRIAD REGION... WITH WINDS THERE NOW FROM THE W OR WNW. UPPER AIR ANALYSES REVEAL STRONG SW WINDS NEAR 50 KTS AT 925-850 MB AHEAD OF THE TROUGH AT THOSE LEVELS (LOCATED RIGHT ALONG THE SPINE OF THE MOUNTAINS)... AND WHILE WINDS BEHIND THE TROUGH FROM THE W OR WNW ARE NOT AS STRONG (CLOSER TO 25-30 KT)... DEEPENING LOW PRESSURE OVER AND JUST OFF THE NORTHEAST COAST LATER TODAY AND SUBSEQUENT HEIGHT RISES OVER CENTRAL NC AND THE MIDATLANTIC REGION SHOULD ALLOW FOR AT LEAST A FEW GUSTS UP TO 25-30 KTS THIS AFTERNOON WITH DECENT MIXING TAKING PLACE. THIS SHOULD FALL BELOW CRITERIA... BUT OUGHT TO LEAD TO SOME OUTDOOR OBJECTS BEING TOSSED AROUND. THE RAIN SHIELD OVER ERN NC INCLUDING THE ERN CWA SUPPORTED BY STRONG PREFRONTAL MOISTURE TRANSPORT AND UPPER LEVEL JET-INDUCED DIVERGENCE IS RUNNING VERY CLOSE TO THE EARLIER FORECAST PACE... SO JUST MINOR ADJUSTMENTS NEEDED... RETAINING CATEGORICAL POPS EAST... AND A HIGH CHANCE HOLDING ON OVER THE WEST WITH NARROW SHOWER BANDS ALONG AND JUST BEHIND THE COLD FRONT. ADDITIONAL RAINFALL SHOULD TOTAL NO MORE THAN A TENTH OF AN INCH. POPS SHOULD DECREASE QUICKLY WEST TO EAST THIS AFTERNOON... WITH DOWNSLOPE FLOW AND STRONG SUBSIDENCE ALREADY LEADING TO CLEARING SKIES NOT TOO FAR BEHIND THE FRONT. TEMPS WILL BE TRICKY... ATYPICALLY PEAKING THIS MORNING OVER THE WEST AND EARLY AFTERNOON EAST... IN THE MID 50S TO AROUND 60... BEFORE FALLING THIS AFTERNOON THROUGH THE 40S. MADE SMALL TWEAKS USING LATEST HRRR GUIDANCE AND CURRENT TRENDS. -GIH && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... AS OF 315 AM MONDAY... CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA MONDAY NIGHT AND INTO THE DAY ON TUESDAY. WINDS LOOK TO DECOUPLE OVERNIGHT...ESPECIALLY IN THE WEST...WHICH SHOULD HELP FOR A WIDE RANGE IN TEMPERATURES. LOWS TUESDAY MORNING IN THE LOWER TO MID 20S...WITH UPPER TEENS POSSIBLE IN THE TYPICALLY COLDER LOCATIONS ACROSS THE WESTERN PIEDMONT. A LOW AMPLITUDE SHORTWAVE WILL CROSS THE AREA ON TUESDAY... WITH LITTLE MORE THAN ENHANCED MID AND UPPER LEVEL CLOUDINESS...WITH HIGHS TUESDAY A 2 CATEGORIES BELOW NORMAL. HIGHS IN THE LOWER 40S TO MID 40S. LOWS TUESDAY NIGHT IN THE MID TO UPPER 20S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 315 AM MONDAY... PERIOD WILL START OUT RELATIVELY BENIGN AS WLY FLOW DOMINATES ALOFT AND AN ARA OF HIGH PRESSURE RETREATS OFFSHORE. RESULTANT LEE SIDE TROUGH AND LOW LEVEL SW FLOW WILL AID TO BOOST AFTERNOON TEMPS INTO THE LOW-MID 50S (CANNOT RULE OUT TEMPS 2-3 DEGREES WARMER IF STRONG INSOLATION OCCURS). THURSDAY...MODEL GUIDANCE IN DECENT AGREEMENT IN TRAVERSING A S/W IN THE SOUTHERN STREAM ACROSS THE NORTHERN GULF WED NIGHT WHILE A S/W DIGS SEWD IN THE NORTHERN STREAM ACROSS THE LOWER OH VALLEY. THE STRONGER NORTHERN STREAM S/W EVENTUALLY CAUSES THE SOUTHERN STREAM SYSTEM TO SHEAR OUT OFF THE SE U.S. COAST THURSDAY. THE TWO SYSTEMS WILL SPREAD VARYING DEGREES OF MOISTURE INTO CENTRAL NC LATE WED NIGHT THROUGH THURSDAY. ANY PRECIP THAT OCCURS THURSDAY WILL BE LIGHT AND MAINLY CONFINED TO THE SE THIRD OF OUR FORECAST AREA. PRECIP WILL INITIALLY FALL FROM CLOUD BASES 6000-8000FT SO IT WILL TAKE A WHILE TO SATURATE THE SUB CLOUD LAYER. THIS WILL LEAD TO SOME EVAPORATIVE COOLING...SETTING THE STAGE FOR A POSSIBLE RAIN/SNOW MIX SCENARIO ACROSS THE NORTHERN PIEDMONT THURSDAY MORNING. (00Z GFS BUFKIT SOUNDINGS DEPICT A POSSIBLE SEEDER FEEDER MECHANISM THURSDAY MORNING ACROSS THE PIEDMONT...AND ACROSS THE SANDHILLS AROUND MID DAY). STILL A LOT OF UNCERTAINTY WHETHER PRECIP WILL OCCUR THIS FAR NORTH. PLUS...MAY BE A CASE OF THE COLD AIR CHASING THE MOISTURE AS BEST CAA OCCURS THURSDAY AFTERNOON (AT THE SAME TIME THE ATMOSPHERE UNDERGOES RAPID DRYING). FOR NOW WILL VARY POPS FROM SLIGHT CHANCE ACROSS THE NORTHWEST HALF...TRENDING TO A 3:1 CHANCE ACROSS THE SE. HIGH TEMPS THURSDAY LOWER 40S NW TO THE UPPER 40S FAR SOUTH. THURSDAY NIGHT THROUGH SUNDAY WILL SEE A CHILLY HIGH PRESSURE SYSTEM BUILD INTO OUR REGION THURSDAY NIGHT/FRIDAY THEN SLIDE SOUTHWARD SATURDAY AND SUNDAY. THUS WILL SEE A VERY COLD DAY FRIDAY FOLLOWED BY A DECENT RECOVERY FOR THE WEEKEND. THICKNESSES EARLY FRIDAY START OUT IN THE MID 1260S. PAST EVENTS WITH SIMILAR THICKNESSES SUGGEST MIN TEMPS NEAR 20/LOWER 20S. AFTERNOON TEMPS FRIDAY MAY FAIL TO REACH 40 ACROSS MOST OF THE PIEDMONT AND NORTHERN COASTAL PLAIN. BY SATURDAY...HIGH PRESSURE WILL BE CENTERED TO OUR SOUTH. WLY FLOW WILL SET-UP A LEE SIDE TROUGH...BACKING SFC WINDS TO A MORE SWLY DIRECTION. THIS WILL INITIATE A WARMING TREND. HIGH TEMPS SATURDAY SHOULD BOUNCE BACK INTO THE UPPER 40S/LOWER 50S...AND LOW-MID 50S SUNDAY. EXPECT AN INCREASE IN CLOUD COVERAGE SUNDAY AS THE NEXT S/W IN THE NORTHERN STREAM AFFECTS OUR REGION. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... AS OF 1255 PM MONDAY... PRIMARY AVIATION CONCERN NEXT 24 HOURS: BLUSTERY AND GUSTY SURFACE WINDS FROM THE NW INTO EARLY THIS EVENING. A COLD FRONT IS CURRENTLY MOVING THROUGH CENTRAL NC... ALREADY THROUGH INT/GSO/RDU/RWI AND TO BE MOVING THROUGH FAY BEFORE 2 PM /19Z/. CIGS HAVE BEEN MAINLY MVFR AT RWI/FAY IN THE LAST HOUR BUT THESE WILL BE CLIMBING TO VFR BEHIND THE FRONT... AS CIGS ARE ALREADY VFR AT INT/GSO/RDU. SURFACE WINDS SUDDENLY SHIFT FROM SW TO NW WITH FRONTAL PASSAGE. SURFACE WINDS AT ALL SITES WILL BE SUSTAINED 10-20 KTS GUSTING FREQUENTLY TO 25-35 KTS WITH ISOLATED HIGHER GUSTS CLOSER TO 40 KTS POSSIBLE. THIS WILL CREATE MECHANICAL TURBULENCE AND POTENTIAL DIFFICULTY ESPECIALLY HANDLING SMALLER AIRCRAFT THROUGH THIS AFTERNOON INTO EARLY EVENING. SKIES WILL CLEAR OUT WITH DIMINISHING NW WINDS (TO UNDER 10 KTS) BY LATE EVENING... AND VFR CONDITIONS WILL HOLD OVERNIGHT THROUGH TUE MORNING AS SURFACE HIGH PRESSURE BUILDS INTO THE AREA. PATCHY OR ISOLATED SHOWERS WILL REMAIN POSSIBLE AT GSO/RDU/RWI/FAY UNTIL AROUND 21Z THIS AFTERNOON... BUT VSBYS WILL REMAIN PREDOMINANTLY VFR. LOOKING BEYOND 18Z TUE... HIGH CONFIDENCE IN PREVAILING VFR CONDITIONS AT ALL CENTRAL NC TAF SITES THROUGH SATURDAY. HIGH PRESSURE WILL BUILD INTO OUR AREA FROM THE WEST TONIGHT... SHIFT OVERHEAD TUE THEN OFFSHORE WED. THERE IS A VERY SMALL CHANCE OF BRIEF MVFR CIGS MAINLY AT FAY/RWI LATE WED NIGHT THROUGH MIDDAY THU AS A DISTURBANCE AND SURFACE LOW PRESSURE AREA SLIDES BY TO OUR SOUTHEAST. BUT OTHERWISE... ANOTHER HIGH PRESSURE AREA (A CHILLY ONE) WILL BUILD IN FROM THE NW FOR LATE THU THROUGH SAT. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM NOON TODAY TO 7 PM EST THIS EVENING FOR NCZ007>011-021>028-038>043-073>078-083>086-088-089. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...CBL LONG TERM...WSS AVIATION...HARTFIELD
AREA FORECAST DISCUSSION
NWS RALEIGH NC
1202 PM EST MON FEB 2 2015 .SYNOPSIS... A STRONG COLD FRONT WILL MOVE EAST OF THE AREA AND OFFSHORE BY LATE THIS AFTERNOON. HIGH PRESSURE WILL BUILD OVER THE REGION THIS EVENING THROUGH MIDWEEK. && .NEAR TERM /TODAY/... AS OF 1202 PM MONDAY... UPDATED: LARGER PRECIP SHIELD IS HEADING OUT OF THE CWA... SO WILL MAKE APPROPRIATE ADJUSTMENTS TO POPS TO ACCOUNT FOR THIS AS WELL AS THE BANDS OF SHOWERS ALONG AND JUST BEHIND THE FRONT. THE FRONT ITSELF IS DEPICTED NICELY ON VIS SATELLITE IMAGERY FROM AROUND ROANOKE RAPIDS TO THE CITY OF RALEIGH TO JUST NW OF WADESBORO. WE`RE STARTING TO GET SOME OF THE LARGER POST-FRONTAL NORTHWESTERLY GUSTS WITHIN THE STRENGTHENING COLD AIR ADVECTION... AS HIGH AS 28-30 KT... WITH A FEW STRONGER GUSTS AT WEST JEFFERSON IN THE LAST HR... SO WE STILL EXPECT NUMEROUS GUSTS IN THE 25-30 KT RANGE (AND SPORADICALLY STRONGER) THIS AFTERNOON... SO THE ADVISORY WILL BE LEFT AS IS. -GIH PREVIOUS DISCUSSION FOR THE REST OF TODAY: WILL LEAVE THE WIND ADVISORY IN EFFECT FOR THIS AFTERNOON... BASED ON ANTICIPATED IMPACTS... ALTHOUGH THERE IS SOME INDICATION THAT WE MAY NOT QUITE GET UP TO ADVISORY CRITERIA. LATEST SURFACE ANALYSIS SHOWS THE COLD FRONT HAVING MOVED THROUGH THE TRIAD REGION... WITH WINDS THERE NOW FROM THE W OR WNW. UPPER AIR ANALYSES REVEAL STRONG SW WINDS NEAR 50 KTS AT 925-850 MB AHEAD OF THE TROUGH AT THOSE LEVELS (LOCATED RIGHT ALONG THE SPINE OF THE MOUNTAINS)... AND WHILE WINDS BEHIND THE TROUGH FROM THE W OR WNW ARE NOT AS STRONG (CLOSER TO 25-30 KT)... DEEPENING LOW PRESSURE OVER AND JUST OFF THE NORTHEAST COAST LATER TODAY AND SUBSEQUENT HEIGHT RISES OVER CENTRAL NC AND THE MIDATLANTIC REGION SHOULD ALLOW FOR AT LEAST A FEW GUSTS UP TO 25-30 KTS THIS AFTERNOON WITH DECENT MIXING TAKING PLACE. THIS SHOULD FALL BELOW CRITERIA... BUT OUGHT TO LEAD TO SOME OUTDOOR OBJECTS BEING TOSSED AROUND. THE RAIN SHIELD OVER ERN NC INCLUDING THE ERN CWA SUPPORTED BY STRONG PREFRONTAL MOISTURE TRANSPORT AND UPPER LEVEL JET-INDUCED DIVERGENCE IS RUNNING VERY CLOSE TO THE EARLIER FORECAST PACE... SO JUST MINOR ADJUSTMENTS NEEDED... RETAINING CATEGORICAL POPS EAST... AND A HIGH CHANCE HOLDING ON OVER THE WEST WITH NARROW SHOWER BANDS ALONG AND JUST BEHIND THE COLD FRONT. ADDITIONAL RAINFALL SHOULD TOTAL NO MORE THAN A TENTH OF AN INCH. POPS SHOULD DECREASE QUICKLY WEST TO EAST THIS AFTERNOON... WITH DOWNSLOPE FLOW AND STRONG SUBSIDENCE ALREADY LEADING TO CLEARING SKIES NOT TOO FAR BEHIND THE FRONT. TEMPS WILL BE TRICKY... ATYPICALLY PEAKING THIS MORNING OVER THE WEST AND EARLY AFTERNOON EAST... IN THE MID 50S TO AROUND 60... BEFORE FALLING THIS AFTERNOON THROUGH THE 40S. MADE SMALL TWEAKS USING LATEST HRRR GUIDANCE AND CURRENT TRENDS. -GIH && .SHORT TERM /TONIGHT THROUGH TUESDAY NIGHT/... AS OF 315 AM MONDAY... CONTINENTAL POLAR HIGH PRESSURE BUILDS INTO THE AREA MONDAY NIGHT AND INTO THE DAY ON TUESDAY. WINDS LOOK TO DECOUPLE OVERNIGHT...ESPECIALLY IN THE WEST...WHICH SHOULD HELP FOR A WIDE RANGE IN TEMPERATURES. LOWS TUESDAY MORNING IN THE LOWER TO MID 20S...WITH UPPER TEENS POSSIBLE IN THE TYPICALLY COLDER LOCATIONS ACROSS THE WESTERN PIEDMONT. A LOW AMPLITUDE SHORTWAVE WILL CROSS THE AREA ON TUESDAY... WITH LITTLE MORE THAN ENHANCED MID AND UPPER LEVEL CLOUDINESS...WITH HIGHS TUESDAY A 2 CATEGORIES BELOW NORMAL. HIGHS IN THE LOWER 40S TO MID 40S. LOWS TUESDAY NIGHT IN THE MID TO UPPER 20S. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... AS OF 315 AM MONDAY... PERIOD WILL START OUT RELATIVELY BENIGN AS WLY FLOW DOMINATES ALOFT AND AN ARA OF HIGH PRESSURE RETREATS OFFSHORE. RESULTANT LEE SIDE TROUGH AND LOW LEVEL SW FLOW WILL AID TO BOOST AFTERNOON TEMPS INTO THE LOW-MID 50S (CANNOT RULE OUT TEMPS 2-3 DEGREES WARMER IF STRONG INSOLATION OCCURS). THURSDAY...MODEL GUIDANCE IN DECENT AGREEMENT IN TRAVERSING A S/W IN THE SOUTHERN STREAM ACROSS THE NORTHERN GULF WED NIGHT WHILE A S/W DIGS SEWD IN THE NORTHERN STREAM ACROSS THE LOWER OH VALLEY. THE STRONGER NORTHERN STREAM S/W EVENTUALLY CAUSES THE SOUTHERN STREAM SYSTEM TO SHEAR OUT OFF THE SE U.S. COAST THURSDAY. THE TWO SYSTEMS WILL SPREAD VARYING DEGREES OF MOISTURE INTO CENTRAL NC LATE WED NIGHT THROUGH THURSDAY. ANY PRECIP THAT OCCURS THURSDAY WILL BE LIGHT AND MAINLY CONFINED TO THE SE THIRD OF OUR FORECAST AREA. PRECIP WILL INITIALLY FALL FROM CLOUD BASES 6000-8000FT SO IT WILL TAKE A WHILE TO SATURATE THE SUB CLOUD LAYER. THIS WILL LEAD TO SOME EVAPORATIVE COOLING...SETTING THE STAGE FOR A POSSIBLE RAIN/SNOW MIX SCENARIO ACROSS THE NORTHERN PIEDMONT THURSDAY MORNING. (00Z GFS BUFKIT SOUNDINGS DEPICT A POSSIBLE SEEDER FEEDER MECHANISM THURSDAY MORNING ACROSS THE PIEDMONT...AND ACROSS THE SANDHILLS AROUND MID DAY). STILL A LOT OF UNCERTAINTY WHETHER PRECIP WILL OCCUR THIS FAR NORTH. PLUS...MAY BE A CASE OF THE COLD AIR CHASING THE MOISTURE AS BEST CAA OCCURS THURSDAY AFTERNOON (AT THE SAME TIME THE ATMOSPHERE UNDERGOES RAPID DRYING). FOR NOW WILL VARY POPS FROM SLIGHT CHANCE ACROSS THE NORTHWEST HALF...TRENDING TO A 3:1 CHANCE ACROSS THE SE. HIGH TEMPS THURSDAY LOWER 40S NW TO THE UPPER 40S FAR SOUTH. THURSDAY NIGHT THROUGH SUNDAY WILL SEE A CHILLY HIGH PRESSURE SYSTEM BUILD INTO OUR REGION THURSDAY NIGHT/FRIDAY THEN SLIDE SOUTHWARD SATURDAY AND SUNDAY. THUS WILL SEE A VERY COLD DAY FRIDAY FOLLOWED BY A DECENT RECOVERY FOR THE WEEKEND. THICKNESSES EARLY FRIDAY START OUT IN THE MID 1260S. PAST EVENTS WITH SIMILAR THICKNESSES SUGGEST MIN TEMPS NEAR 20/LOWER 20S. AFTERNOON TEMPS FRIDAY MAY FAIL TO REACH 40 ACROSS MOST OF THE PIEDMONT AND NORTHERN COASTAL PLAIN. BY SATURDAY...HIGH PRESSURE WILL BE CENTERED TO OUR SOUTH. WLY FLOW WILL SET-UP A LEE SIDE TROUGH...BACKING SFC WINDS TO A MORE SWLY DIRECTION. THIS WILL INITIATE A WARMING TREND. HIGH TEMPS SATURDAY SHOULD BOUNCE BACK INTO THE UPPER 40S/LOWER 50S...AND LOW-MID 50S SUNDAY. EXPECT AN INCREASE IN CLOUD COVERAGE SUNDAY AS THE NEXT S/W IN THE NORTHERN STREAM AFFECTS OUR REGION. && .AVIATION /12Z MONDAY THROUGH FRIDAY/... AS OF 630 AM MONDAY... 24-HR TAF PERIOD: WIDESPREAD SHOWERS WITH MVFR CEILINGS ARE EXPECTED TO SPREAD EAST ACROSS THE AREA THROUGH 15Z AS LOW-LEVEL MOISTURE. A BRIEF PERIOD OF IFR CEILINGS WILL BE POSSIBLE WITHIN THE HEAVIER SHOWER ACTIVITY. A SECONDARY AREA OF SHOWERS COULD RE-DEVELOP BETWEEN 15 TO 18Z FROM RDU EASTWARD AS THE FRONT MOVES THROUGH THE AREA. STRONG DRY COLD AIR ADVECTION WILL BRING A RAPID RETURN TO VFR CONDITIONS BEHIND THE FRONT...WITH STRONG NWLY WINDS BECOMING SUSTAINED AT 15-20 KT WITH GUSTS TO 35-40KTS THROUGH THE LATE AFTERNOON/EARLY EVENING. WINDS WILL GRADUALLY SUBSIDE OVERNIGHT..EVENTUALLY BECOMING LIGHT/ VARIABLE BY 12Z TUE MORNING. LOOKING AHEAD: VFR CONDITIONS WILL PERSIST THROUGH MID WEEK. A MOSTLY DRY COLD FRONT MOVES THROUGH THE AREA WEDNESDAY NIGHT. AN AREA OF LOW PRESSURE SYSTEM TRACKING FROM THE GULF OF MEXICO AND OFF THE SOUTHEAST COAST COULD BRING SOME SUB-VFR CONDITIONS TO EASTERN TERMINALS ON THURSDAY. && .RAH WATCHES/WARNINGS/ADVISORIES... WIND ADVISORY FROM NOON TODAY TO 7 PM EST THIS EVENING FOR NCZ007>011-021>028-038>043-073>078-083>086-088-089. && $$ SYNOPSIS...HARTFIELD NEAR TERM...HARTFIELD SHORT TERM...CBL LONG TERM...WSS AVIATION...CBL
AREA FORECAST DISCUSSION
NWS BISMARCK ND
1233 PM CST MON FEB 2 2015 .UPDATE... ISSUED AT 1227 PM CST MON FEB 2 2015 THE REMNANTS OF THE WEAK CLIPPER MOVING OUT OF THE REGION QUICKLY. LEFT SOME POPS ALONG THE SOUTH DAKOTA BORDER THAT TRANSITION TO FLURRIES LATE THIS AFTERNOON. SKIES CLEARING NORTH AND WEST IN SUBSIDENCE BEHIND THE LOW. TEMPERATURES LOOK GOOD FOR THE AFTERNOON. UPDATE ISSUED AT 928 AM CST MON FEB 2 2015 UPDATED THE FORECAST TO INCREASE SNOW TO LIKELY THROUGH THE NEXT 2 HOURS IN THE AREAS SHOWING SNOW ACROSS THE SOUTHWEST. STILL EXPECTING ONLY TRACE AMOUNTS TO MAYBE A HALF INCH OF SNOW. UPDATE ISSUED AT 644 AM CST MON FEB 2 2015 LOW PRESSURE OVER SOUTHEAST MONTANA INTO NORTHEAST WYOMING WITH A WEAK INVERTED TROUGH INTO NORTHWEST NORTH DAKOTA WILL MOVE SOUTHEAST TODAY. LIGHT SNOW OVER A GOOD PORTION OF EASTERN MONTANA IS JUST BEGINNING TO MOVE INTO WESTERN NORTH DAKOTA. CURRENT FORECAST LOOKS IN GOOD SHAPE WITH LIGHT SNOW MAINLY OVER THE WEST AND FAR SOUTH CENTRAL DURING THE MORNING HOURS...TAPERING OFF IN THE FAR SOUTHWEST AND SOUTH CENTRAL THIS AFTERNOON. DID BUMP UP POPS TO LIKELY ALONG THE MONTANA BORDER THIS MORNING. LOWS HAVE BEEN REACHED AS TEMPERATURES ARE RISING ACROSS THE FORECAST AREA. UPDATED LATEST SENSIBLE WEATHER ELEMENTS. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FOCUS FOR THE SHORT TERM IS LIGHT SNOW. A WEAK UPPER LEVEL SHORTWAVE TROUGH AND ASSOCIATED SURFACE LOW CURRENTLY OVER MONTANA WILL CONTINUE TO PROPAGATE SOUTHEAST THIS MORNING...EVENTUALLY SKIRTING SOUTHWEST NORTH DAKOTA. REGIONAL RADAR IS SHOWING SOME LIGHT BANDS OF SNOW ACROSS CENTRAL AND EASTERN MONTANA ASSOCIATED WITH THIS LOW. THIS AREA OF SNOW IS EXPECTED TO SLOWLY SAG SOUTH AND EAST THROUGH THE MORNING HOURS. THE MAIN QUESTION IS WHETHER OR NOT THIS AREA OF SNOW WILL HOLD TOGETHER AND HOW FAR EAST IT WILL MOVE. LATEST SHORT TERM GUIDANCE SUGGESTS THAT THE AREA OF SNOW WILL BRUSH WESTERN AND SOUTHERN NORTH DAKOTA THIS MORNING BUT WILL DIMINISH IN INTENSITY LEAVING ONLY A DUSTING TO LESS THAN A HALF INCH OF SNOW ACROSS PORTIONS OF WESTERN AND SOUTHERN NORTH DAKOTA. FEEL THE 09 UTC HRRR HAS A PRETTY GOOD HANDLE ON THE SITUATION AS IT IS PRETTY CLOSE IN DEPICTING CURRENT SNOW BANDS IN EASTERN MONTANA. THE 09 UTC HRRR CONTINUES TO BRING THAT BAND OF SNOW EASTWARD INTO WESTERN NORTH DAKOTA THIS MORNING...BUT DIMINISHES AND SCATTERS OUT THE SNOW LATER THIS MORNING. FROM THERE OUR ATTENTION TURNS TO TONIGHT WHEN WE HAVE YET ANOTHER CHANCE FOR SNOW. ALL THE MAJOR MODELS ARE SHOWING A WELL DEFINED AREA OF SNOW ENTERING THE REGION AROUND MIDNIGHT AND SPREADING SOUTH AND EAST THROUGH THE DAY TUESDAY. THE MODELS ARE ALSO CONSISTENT WITH RESPECT TO LOCATION AND AMOUNTS OF PRECIPITATION. AT THIS TIME IT APPEARS WEST CENTRAL NORTH DAKOTA IS THE MOST FAVORED LOCATION FOR SNOWFALL...WITH AROUND 2 INCHES TOTAL ACCUMULATION POSSIBLE. .LONG TERM...(TUESDAY THROUGH SUNDAY) ISSUED AT 339 AM CST MON FEB 2 2015 THE MAIN FORECAST CONCERNS IN THE LONG TERM ARE SNOW CHANCES TUESDAY AND TUESDAY NIGHT...AND THEN PRECIPITATION CHANCES AND TYPE FRIDAY THROUGH SATURDAY. DETERMINISTIC MODELS ARE IN REASONABLE AGREEMENT WITH THE SYSTEM MOVING THROUGH LATE MONDAY NIGHT AND TUESDAY. THE GFS IS THE OUTLIER WITH THE QPF PLACEMENT WITH THIS SYSTEM. ALL OTHER MODELS ARE FARTHER NORTH AND EAST. UTILIZED A MODEL BLEND WITH THE NAM/SREF/GEM/ECMWF AND GFS. THUS NOT TOTALLY DISCOUNTING THE GFS TRACK BUT THIS DOES RESULT IN A LITTLE FARTHER NORTHERN TRACK WITH THE QPF. PREVIOUS TRACK HAD HIGHEST SNOW TOTALS FROM AROUND BEACH TO SOUTH OF BISMARCK AND IS NOW BETWEEN BEACH AND WILLISTON...THROUGH BISMARCK...TO ELLENDALE. AND WITH LESSER AMOUNTS IN THE FAR SOUTHWEST. OVERALL NOT A BIG CHANGE AND GENERALLY 1-2 INCHES OVER ALL BUT THE FAR SOUTHWEST WHERE ACCUMULATIONS MAY TOTAL AN INCH OR LESS...AND THE FAR NORTH CENTRAL FROM SHERWOOD AND MOHALL TO RUGBY AND NORTH WHERE AMOUNTS ARE EXPECTED TO BE A HALF INCH OR LESS. OF COURSE THE RESULTING TRACK IS STILL SUBJECT TO CHANGE...BUT THE TOTAL SNOW AMOUNTS HAVE BEEN VERY CONSISTENT FOR THE PAST TWO DAYS. AFTER A DRY PERIOD WEDNESDAY THROUGH THURSDAY NIGHT WE SEE ANOTHER SERIES OF IMPULSES MOVING THROUGH A STRONG NORTHWEST FLOW FRIDAY THROUGH SATURDAY NIGHT AND INTERACTING WITH THE BAROCLINIC ZONE. BY THIS TIME THE BAROCLINIC ZONE HAS SHIFTED FARTHER NORTH OVER NORTHERN INTO EASTERN NORTH DAKOTA. THERE ARE ALREADY TIMING DIFFERENCES WITH THE GFS MUCH QUICKER WITH THE FIRST IMPULSE AND ITS ASSOCIATED SURFACE LOW MOVING THROUGH MUCH QUICKER ON FRIDAY THAN BOTH THE ECMWF/GEM. THERE ARE ALSO DIFFERENCES IN THE EVOLUTION OF THE BAROCLINIC ZONE AS THE ECMWF KEEPS IT FROM NORTHERN INTO EASTERN NORTH DAKOTA FRIDAY AND FRIDAY NIGHT...THEN SAGS IT SOUTH THROUGH ALL BUT THE FAR SOUTHWEST BY SATURDAY NIGHT. THE QUICKER GFS DROPS THE BZ SOUTH FRIDAY...LIFTS IT BACK NORTH ON SATURDAY AND DROPS IT BACK DOWN SATURDAY NIGHT BEHIND A QUICK MOVING CLIPPER. THE GEM BRINGS IT DOWN SLIGHTLY ON FRIDAY THEN BEGINS TO LIFT IT WELL NORTH OF THE STATE ON SATURDAY. WITH ALL THAT...SEE NO REASON AT THIS TIME TO DEVIATE FROM A MODEL BLEND FOR POPS WHICH BRINGS MAINLY CHANCE POPS TO THE NORTH FRIDAY AND THEN SOUTH ACROSS ALL BUT THE SOUTHWEST SATURDAY...AND EXITING TO THE EAST SATURDAY NIGHT. THE MAIN CONCERN HERE IS THAT THERE WILL PROBABLY BE A CHANCE OF SOME MIXED PRECIPITATION ON THE SOUTHERN PERIPHERY OF THE BAROCLINIC ZONE...WHEREVER IT MAY BE...AND THIS WILL HAVE TO BE MONITORED AS WE GO THROUGH THE WEEK. AS FAR AS TEMPERATURES ARE CONCERNED...WE REMAIN COLD ON TUESDAY AND WEDNESDAY. WIND CHILL HEADLINES WILL PROBABLY BE NEEDED LATE TUESDAY NIGHT INTO WEDNESDAY MORNING OVER THE NORTH CENTRAL. AS THE BAROCLINIC ZONE SHIFTS NORTH WE WARM INTO THE 20S NORTHEAST TO THE 40S SOUTHWEST. THEN FRIDAY THROUGH SUNDAY THE TEMPERATURE GRADIENT SHARPENS EVEN MORE WITH HIGHS IN THE SINGLE DIGITS AND LOW TEENS OVER THE TURTLE MOUNTAINS AREA IN THE NORTH CENTRAL...TO THE MID AND UPPER 40S OVER THE SOUTHWEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1227 PM CST MON FEB 2 2015 FAST MOVING BUT WEAK TROUGH OF LOW PRESSURE EXITING THE REGION WITH CLEARING SKIES NORTH AND WEST FOR THE AFTERNOON. VFR EXPECTED THIS AFTERNOON AND EVENING. NEXT FAST MOVING LOW PRESSURE WILL SPREAD LIGHT SNOW ACROSS THE WEST AND SOUTH AFTER MIDNIGHT TONIGHT. CONDITIONS DETERIORATING TO IFR IN SNOW AFTER 06Z. && .BIS WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...WAA SHORT TERM...AJ LONG TERM...TWH AVIATION...WAA
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1144 AM CST MON FEB 2 2015 .DISCUSSION... UPDATED FOR 18Z AVIATION DISCUSSION. && .PREV DISCUSSION... /ISSUED 1016 AM CST MON FEB 2 2015/ DISCUSSION... GUSTY NW WINDS ARE STARTING TO DIMINISH ACROSS THE REGION AS COLD HIGH PRESSURE MOVES OVER THE REGION. LOW CLOUDS ARE ERODING WEST OF THE MS RIVER WITH SOME HOLES APPEARING OVER WEST TN. CLOUDS WILL CONTINUE TO ERODE THIS AFTERNOON WITH INCREASING SUNSHINE. CURRENT TEMPS RANGE FROM THE LOWER 20S ALONG THE KY BORDER TO AROUND THE FREEZING MARK ACROSS THE SOUTH. TEMPS WILL STRUGGLE TO REACH 30 ACROSS THE NORTH TO UPPER 30S SOUTH THIS AFTERNOON. TWEAKED CLOUD COVER OTRW FORECAST LOOKS GOOD. SJM && .PREV DISCUSSION... /ISSUED 641 AM CST MON FEB 2 2015/ .UPDATE... RECEIVED A REPORT OF LIGHT SNOW WITH A DUSTING ON CARS IN MCKENZIE TN IN NORTHWEST TN. UPDATED TO INCLUDE UNTIL MID-MORNING A SLIGHT CHANCE OF LIGHT SNOW FOR PORTIONS OF WEST TN...AND ISOLATED FLURRIES ELSEWHERE WITH SOME RADAR RETURNS BEING INDICATED. JCL && .DISCUSSION... /ISSUED 423 AM CST MON FEB 2 2015/ STRONG AND GUSTY NORTHWEST WINDS WERE FEEDING MUCH COLDER AIR INTO THE MIDSOUTH EARLY THIS MORNING. TEMPERATURES WERE IN THE 30S WITH WIND CHILL READINGS IN THE TEENS IN MANY LOCATIONS. LOW CLOUDS CONTINUED TO COVER THE REGION. OTHER THAN THE MUCH COLDER WEATHER TODAY...THE MAIN WEATHER STORY THIS WEEK WILL BE THE THREAT OF LIGHT SNOW ACCUMULATIONS WEDNESDAY NIGHT. FOR TODAY...A FEW SNOW FLURRIES MAY OCCUR ALONG THE TN RIVER VALLEY UNTIL ABOUT SUNRISE AS AN UPPER LEVEL TROUGH MOVES THROUGH THIS REGION. OTHERWISE...PRECIPITATION FREE WEATHER WILL OCCUR AS STRONG HIGH PRESSURE OVER THE PLAINS MOVE INTO THE MIDSOUTH AND UPPER LEVEL HEIGHTS INCREASE. TEMPERATURES WILL NOT CLIMB MUCH TODAY AND WILL REACH HIGHS ONLY A LITTLE BELOW FREEZING IN MANY SPOTS ALONG THE MO AND KY BORDERS. CLOUDS ARE FORECAST TO DECREASE THIS AFTERNOON... ALTHOUGH CONFIDENCE IS LOW WITH THE RAP MODEL KEEPING THE LOW CLOUDS OVER MUCH OF THE AREA THROUGH THIS AFTERNOON. A COLD NIGHT IS FORECAST TONIGHT WITH MOSTLY CLEAR TO PARTLY SKIES SKIES. LOW TEMPERATURES WILL RANGE FROM THE UPPER TEENS NEAR THE TN RIVER VALLEY OF WEST TN TO THE LOWER AND MIDDLE 20S ELSEWHERE. HIGH PRESSURE WILL MOVE SLOWLY TO THE EAST. FOLLOWING A COLD MORNING TUESDAY...TEMPERATURES WILL REBOUND IN THE AFTERNOON TO BETWEEN THE MIDDLE 40S AND LOWER 50S. HIGH PRESSURE WILL MOVE TO NEAR THE ATLANTIC COAST WITH INCREASING SOUTHWEST WINDS AND ABUNDANT SUNSHINE ACROSS THE MIDSOUTH. DRY WEATHER WILL CONTINUE TUESDAY NIGHT. LATEST MODELS INDICATE THAT THE DRY WEATHER WILL CONTINUE THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT... WILL BE WATCHING LOW PRESSURE MOVING TO OUR SOUTH AND AN ARCTIC COLD FRONT PUSHING INTO THE AREA FROM THE NORTH. STILL HAVE TO WORK OUT THE DETAILS AND TIMING OF THESE FEATURES...THE ECMWF AND GFS ARE STILL NOT IN THE BEST AGREEMENT. THE ARCTIC COLD FRONT WILL BE MOVING SOUTHWARD THROUGH MO WEDNESDAY...THE GFS IS FASTER THAN THE ECMWF. AROUND MIDDAY WEDNESDAY...THE GFS HAS THE FRONT MOVING INTO SOUTHERN MO WHILE THE ECMWF HAS THE FRONT THROUGH CENTRAL MO. MEANWHILE...AN UPPER LEVEL TROUGH WILL MOVE OFF THE TX COAST WITH LOW PRESSURE DEVELOPING OVER THE NORTHWEST GULF. KEPT IN A 20 PERCENT CHANCE OF RAIN FOR MUCH OF THE AREA WEDNESDAY AFTERNOON...ALTHOUGH IF THE FASTER GFS VERIFIES THEN RAIN CHANCES MAY NEED TO BE INCREASED ACROSS PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL INTO NORTHWEST TN. LATEST GFS AND ECMWF KEEP MOST IF NOT ALL OF THE RAIN WITH THE SOUTHERN LOW TO OUR SOUTH AS THE LOW TRACKS EASTWARD...BUT THE NAM IS A LITTLE FURTHER NORTH WITH THE RAIN GETTING CLOSE TO PORTIONS OF NORTH MS. WEDNESDAY NIGHT...STILL LOOKS INTERESTING WITH A THREAT OF LIGHT SNOW ACCUMULATIONS. THE ARCTIC COLD FRONT IS FORECAST TO CONTINUE PRESSING SOUTHWARD THROUGH THE REGION FOLLOWED BY MUCH COLDER AIR. AN UPPER LEVEL SHORT WAVE AND ASSOCIATED JET STREAK APPROACHING FROM THE NORTHWEST IS FORECAST TO PRODUCE LIFT OVER THE COLD AIR WITH RAIN CHANGING TO SNOW. THE GFS IS THE STRONGEST WITH THIS DISTURBANCE AND MORE OVER THE MIDSOUTH...PRODUCING SNOW AMOUNTS BETWEEN 1 AND 2 INCHES IN SOME LOCATIONS ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. THE ECMWF IS WEAKER AND A LITTLE FURTHER NORTH WITH THE DISTURBANCE AND INDICATES ABOUT 1/2 INCH OR LESS SNOW FOR MUCH OF THE MIDSOUTH. FOR NOW...TOOK MORE OF A COMPROMISE BETWEEN THE TWO. CONTINUED WORDING OF LIGHT SNOW ACCUMULATIONS IN THE HAZARDOUS WEATHER OUTLOOK AS IT IS TOO SOON TO PINPOINT ACCUMULATIONS. CONFIDENCE CONTINUES LOW WITH THE MODELS STILL NOT IN SYNC. BOTH THE ECMWF AND GFS INDICATE THAT ANY SNOW WILL MOVE QUICKLY OUT OF THE AREA EARLY THURSDAY MORNING WITH A RETURN TO SUNSHINE BY AFTERNOON. TEMPERATURES WILL BE COLD THURSDAY INTO FRIDAY MORNING AS MODIFIED ARCTIC AIR SETTLES OVER THE REGION. A WARMING TREND WILL OCCUR FRIDAY AFTERNOON INTO THE WEEKEND AS HIGH PRESSURE MOVES TO ALONG THE ATLANTIC COAST AND WIND TURN TO THE SOUTH ACROSS THE MIDSOUTH. THE NEXT CHANCE OF RAIN WILL BE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT APPROACHES AND MOVES INTO THE AREA FROM THE NORTHWEST. JCL && .AVIATION... SOME MVFR CONDITIONS STILL EXIST ACROSS THE REGION WITH JBR ALREADY SHOWING IMPROVEMENT ABOVE THAT THRESHOLD. WINDS HAVE CONTINUED TO BE STRONGER THAN GUIDANCE FROM THE NORTH...THEREFORE HAVE CONTINUED THAT TREND THROUGH THE MORNING. A GRADUAL DISSIPATION OF THE CLOUD DECK SHOULD OCCUR TODAY AS WINDS BACK AROUND TO THE NORTHEAST AND EVENTUALLY SOUTHEAST AFTER 00Z TUESDAY. VFR CONDITIONS WILL PREVAIL AT ALL SITES AFTER 18-21Z...EARLIER WEST...LATER AT EASTERN TERMINALS. TVT && .AVIATION... MVFR AT MEM...TUP...AND MKL TO START...BUT EXPECTING VFR WEATHER AT ALL SITES OVER THE NEXT FEW HOURS...CONTINUING THEN THROUGHOUT THE PERIOD. NORTHWEST WINDS IN THE 8-12 KT RANGE WILL SUBSIDE BEFORE SUNSET...VEERING SOUTHERLY LATE. JAB && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS MEMPHIS TN
1016 AM CST MON FEB 2 2015 .DISCUSSION... GUSTY NW WINDS ARE STARTING TO DIMINISH ACROSS THE REGION AS COLD HIGH PRESSURE MOVES OVER THE REGION. LOW CLOUDS ARE ERODING WEST OF THE MS RIVER WITH SOME HOLES APPEARING OVER WEST TN. CLOUDS WILL CONTINUE TO ERODE THIS AFTERNOON WITH INCREASING SUNSHINE. CURRENT TEMPS RANGE FROM THE LOWER 20S ALONG THE KY BORDER TO AROUND THE FREEZING MARK ACROSS THE SOUTH. TEMPS WILL STRUGGLE TO REACH 30 ACROSS THE NORTH TO UPPER 30S SOUTH THIS AFTERNOON. TWEAKED CLOUD COVER OTRW FORECAST LOOKS GOOD. SJM && .PREV DISCUSSION... /ISSUED 641 AM CST MON FEB 2 2015/ UPDATE... RECEIVED A REPORT OF LIGHT SNOW WITH A DUSTING ON CARS IN MCKENZIE TN IN NORTHWEST TN. UPDATED TO INCLUDE UNTIL MID-MORNING A SLIGHT CHANCE OF LIGHT SNOW FOR PORTIONS OF WEST TN...AND ISOLATED FLURRIES ELSEWHERE WITH SOME RADAR RETURNS BEING INDICATED. JCL DISCUSSION... /ISSUED 423 AM CST MON FEB 2 2015/ STRONG AND GUSTY NORTHWEST WINDS WERE FEEDING MUCH COLDER AIR INTO THE MIDSOUTH EARLY THIS MORNING. TEMPERATURES WERE IN THE 30S WITH WIND CHILL READINGS IN THE TEENS IN MANY LOCATIONS. LOW CLOUDS CONTINUED TO COVER THE REGION. OTHER THAN THE MUCH COLDER WEATHER TODAY...THE MAIN WEATHER STORY THIS WEEK WILL BE THE THREAT OF LIGHT SNOW ACCUMULATIONS WEDNESDAY NIGHT. FOR TODAY...A FEW SNOW FLURRIES MAY OCCUR ALONG THE TN RIVER VALLEY UNTIL ABOUT SUNRISE AS AN UPPER LEVEL TROUGH MOVES THROUGH THIS REGION. OTHERWISE...PRECIPITATION FREE WEATHER WILL OCCUR AS STRONG HIGH PRESSURE OVER THE PLAINS MOVE INTO THE MIDSOUTH AND UPPER LEVEL HEIGHTS INCREASE. TEMPERATURES WILL NOT CLIMB MUCH TODAY AND WILL REACH HIGHS ONLY A LITTLE BELOW FREEZING IN MANY SPOTS ALONG THE MO AND KY BORDERS. CLOUDS ARE FORECAST TO DECREASE THIS AFTERNOON... ALTHOUGH CONFIDENCE IS LOW WITH THE RAP MODEL KEEPING THE LOW CLOUDS OVER MUCH OF THE AREA THROUGH THIS AFTERNOON. A COLD NIGHT IS FORECAST TONIGHT WITH MOSTLY CLEAR TO PARTLY SKIES SKIES. LOW TEMPERATURES WILL RANGE FROM THE UPPER TEENS NEAR THE TN RIVER VALLEY OF WEST TN TO THE LOWER AND MIDDLE 20S ELSEWHERE. HIGH PRESSURE WILL MOVE SLOWLY TO THE EAST. FOLLOWING A COLD MORNING TUESDAY...TEMPERATURES WILL REBOUND IN THE AFTERNOON TO BETWEEN THE MIDDLE 40S AND LOWER 50S. HIGH PRESSURE WILL MOVE TO NEAR THE ATLANTIC COAST WITH INCREASING SOUTHWEST WINDS AND ABUNDANT SUNSHINE ACROSS THE MIDSOUTH. DRY WEATHER WILL CONTINUE TUESDAY NIGHT. LATEST MODELS INDICATE THAT THE DRY WEATHER WILL CONTINUE THROUGH WEDNESDAY MORNING. FOR WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT... WILL BE WATCHING LOW PRESSURE MOVING TO OUR SOUTH AND AN ARCTIC COLD FRONT PUSHING INTO THE AREA FROM THE NORTH. STILL HAVE TO WORK OUT THE DETAILS AND TIMING OF THESE FEATURES...THE ECMWF AND GFS ARE STILL NOT IN THE BEST AGREEMENT. THE ARCTIC COLD FRONT WILL BE MOVING SOUTHWARD THROUGH MO WEDNESDAY...THE GFS IS FASTER THAN THE ECMWF. AROUND MIDDAY WEDNESDAY...THE GFS HAS THE FRONT MOVING INTO SOUTHERN MO WHILE THE ECMWF HAS THE FRONT THROUGH CENTRAL MO. MEANWHILE...AN UPPER LEVEL TROUGH WILL MOVE OFF THE TX COAST WITH LOW PRESSURE DEVELOPING OVER THE NORTHWEST GULF. KEPT IN A 20 PERCENT CHANCE OF RAIN FOR MUCH OF THE AREA WEDNESDAY AFTERNOON...ALTHOUGH IF THE FASTER GFS VERIFIES THEN RAIN CHANCES MAY NEED TO BE INCREASED ACROSS PORTIONS OF NORTHEAST AR AND THE MO BOOTHEEL INTO NORTHWEST TN. LATEST GFS AND ECMWF KEEP MOST IF NOT ALL OF THE RAIN WITH THE SOUTHERN LOW TO OUR SOUTH AS THE LOW TRACKS EASTWARD...BUT THE NAM IS A LITTLE FURTHER NORTH WITH THE RAIN GETTING CLOSE TO PORTIONS OF NORTH MS. WEDNESDAY NIGHT...STILL LOOKS INTERESTING WITH A THREAT OF LIGHT SNOW ACCUMULATIONS. THE ARCTIC COLD FRONT IS FORECAST TO CONTINUE PRESSING SOUTHWARD THROUGH THE REGION FOLLOWED BY MUCH COLDER AIR. AN UPPER LEVEL SHORT WAVE AND ASSOCIATED JET STREAK APPROACHING FROM THE NORTHWEST IS FORECAST TO PRODUCE LIFT OVER THE COLD AIR WITH RAIN CHANGING TO SNOW. THE GFS IS THE STRONGEST WITH THIS DISTURBANCE AND MORE OVER THE MIDSOUTH...PRODUCING SNOW AMOUNTS BETWEEN 1 AND 2 INCHES IN SOME LOCATIONS ESPECIALLY ALONG AND NORTH OF INTERSTATE 40. THE ECMWF IS WEAKER AND A LITTLE FURTHER NORTH WITH THE DISTURBANCE AND INDICATES ABOUT 1/2 INCH OR LESS SNOW FOR MUCH OF THE MIDSOUTH. FOR NOW...TOOK MORE OF A COMPROMISE BETWEEN THE TWO. CONTINUED WORDING OF LIGHT SNOW ACCUMULATIONS IN THE HAZARDOUS WEATHER OUTLOOK AS IT IS TOO SOON TO PINPOINT ACCUMULATIONS. CONFIDENCE CONTINUES LOW WITH THE MODELS STILL NOT IN SYNC. BOTH THE ECMWF AND GFS INDICATE THAT ANY SNOW WILL MOVE QUICKLY OUT OF THE AREA EARLY THURSDAY MORNING WITH A RETURN TO SUNSHINE BY AFTERNOON. TEMPERATURES WILL BE COLD THURSDAY INTO FRIDAY MORNING AS MODIFIED ARCTIC AIR SETTLES OVER THE REGION. A WARMING TREND WILL OCCUR FRIDAY AFTERNOON INTO THE WEEKEND AS HIGH PRESSURE MOVES TO ALONG THE ATLANTIC COAST AND WIND TURN TO THE SOUTH ACROSS THE MIDSOUTH. THE NEXT CHANCE OF RAIN WILL BE SATURDAY NIGHT AND SUNDAY AS A COLD FRONT APPROACHES AND MOVES INTO THE AREA FROM THE NORTHWEST. JCL && .AVIATION... SOME MVFR CONDITIONS STILL EXIST ACROSS THE REGION WITH JBR ALREADY SHOWING IMPROVEMENT ABOVE THAT THRESHOLD. WINDS HAVE CONTINUED TO BE STRONGER THAN GUIDANCE FROM THE NORTH...THEREFORE HAVE CONTINUED THAT TREND THROUGH THE MORNING. A GRADUAL DISSIPATION OF THE CLOUD DECK SHOULD OCCUR TODAY AS WINDS BACK AROUND TO THE NORTHEAST AND EVENTUALLY SOUTHEAST AFTER 00Z TUESDAY. VFR CONDITIONS WILL PREVAIL AT ALL SITES AFTER 18-21Z...EARLIER WEST...LATER AT EASTERN TERMINALS. TVT && .MEG WATCHES/WARNINGS/ADVISORIES... AR...NONE. MO...NONE. MS...NONE. TN...NONE. && $$
AREA FORECAST DISCUSSION
NWS AMARILLO TX
1120 AM CST MON FEB 2 2015 .AVIATION... NOW THAT THE STRATUS AT KDHT HAS STARTED TO MIX OUT ALL TERMINALS WILL BE VFR AND ARE EXPECTED TO REMAIN VFR FOR THE NEXT 24 HOURS. A STRONG SURFACE PRESSURE GRADIENT WILL KEEP SUSTAINED WINDS IN THE 15-25KT RANGE WITH GUSTS UP TO 35KT THROUGH MOST OF THE DAYLIGHT HOURS TODAY. AS SUNSET APPROACHES...THE PRESSURE GRADIENT WILL WEAKEN AND ALLOW WINDS TO DROP TO 10KT THROUGH THE OVERNIGHT HOURS AND INTO TOMORROW MORNING. THERE IS A CHANCE FOR FOG TO DEVELOP OVERNIGHT..BUT CONFIDENCE ISN`T STRONG ENOUGH TO INCLUDE IN PREVAILING GIVEN STEADY DOWNSLOPE FLOW OVERNIGHT. && PREV DISCUSSION... /ISSUED 318 AM CST MON FEB 2 2015/ DISCUSSION... EARLY THIS MORNING 11-3.9 IR AND SURFACE OBS SHOWED PERSISTENT STRATUS ACROSS MAINLY THE WESTERN HALF OF THE AREA. SURFACE HIGH IN THE WAKE OF DEPARTING SHORTWAVE NOW OVER THE MID/LOWER MISSISSIPPI VALUE WAS MOVING SOUTHEASTWARD AND SOUTHERLY SURFACE WINDS HAVE INCREASED IN THE WESTERN PORTION OF THE PANHANDLES. WATER VAPOR AND 500 MB RAP ANALYSIS LOOP SHOW PACIFIC MOISTURE STREAMING EASTWARD IN INCREASING MOMENTUM ACROSS THE WESTERN CONUS. AS CROSS MOUNTAIN FLOW STRENGTHENS TODAY SO WILL LEE SIDE SURFACE TROUGH. PRESSURE GRADIENT BETWEEN STRENGTHENING LEE TROUGH AND DEPARTING SURFACE HIGH WILL RESULT IN BREEZY SOUTHWESTERLY WINDS THROUGH AFTERNOON. RISING HEIGHTS AND WARMING ALOFT IN ADDITION TO FULL SUN...MIXING...AND AT LEAST SOMEWHAT OF A DOWNSLOPE COMPONENT TO SURFACE WINDS WILL RESULT IN A WARMING TREND TODAY AND TOMORROW. ATTENTION THEN SHIFTS TO A COLD FRONT THAT WILL PASS THROUGH ON WEDNESDAY. GIVEN TRAJECTORIES FAVORING ONLY A MODESTLY COLD AIR MASS...AM LESS CONCERNED ABOUT SIGNIFICANT FRONTAL TIMING ISSUES THAT ARE TYPICAL OF SHALLOW VERY COLD ARCTIC FRONTS. HAVE THE FRONT MOVING THROUGH FASTER THAN MODEL CONSENSUS BUT NOT QUITE AS FAST AS THE GFS AS THE GFS/GEFS MEAN ARE AN OUTLIER WITH HOW FAST NORTHERN STREAM SHORTWAVE (THAT IS FORCING THIS COLD SURGE) MOVES THROUGH THE MIDWEST COMPARED TO OTHER MODEL GUIDANCE. THIS CHOSEN TIMING IS FAIRLY CONSISTENT WITH THE PREVIOUS FORECAST. THE TIMING THAT WE HAVE AT THIS POINT NECESSITATED A NON-CLIMO DIURNAL CURVE WHICH WAS CONSTRUCTED USING HOURLY TEMPERATURE GRIDS. THIS RESULTS IN A TIGHT GRADIENT IN THE HIGH TEMPERATURE GRID FOR WEDNESDAY. IN FACT...IF THE SLOWER FRONTAL TIMING OCCURS...THE WEST AND ESPECIALLY SOUTHWEST TEXAS PANHANDLE MAY SIGNIFICANTLY EXCEED NORMAL HIGH TEMPERATURES WEDNESDAY AFTERNOON. ADJUSTMENTS ON TEMPERATURES WILL NEED TO BE MADE IN SUBSEQUENT FORECASTS DEPENDING ON FRONTAL TIMING. OTHER SENSIBLE WEATHER CHANGES INCLUDE A GOOD CHANCE OF POST-FRONTAL LOW STRATUS LATE WEDNESDAY LASTING INTO THURSDAY MORNING. THE BEST MOISTURE AND DEEPEST LIFT WILL REMAIN NORTHEAST OF THE AREA AND CHANCES OF MEASURABLE PRECIPITATION LOOK TO BE CONFINED TO PORTIONS OF CENTRAL KANSAS ON WEDNESDAY. KEPT MENTION OF SNOW FLURRIES WITH NON- MEASURABLE LIQUID AMOUNTS IN THE FAR NORTHEAST GIVEN A MODESTLY DEEP SATURATED LAYER IN THE LOW LEVELS BUT CONFIDENCE IN EVEN TRACE AMOUNTS IS NOT PARTICULARLY HIGH. FROM LATE WEEK THROUGH THE WEEKEND THE LARGE SCALE PATTERN FEATURES BUILDING LOW AMPLITUDE RIDGING RESULTING IN ABOVE NORMAL TEMPERATURES AND DRY CONDITIONS. FRIDAY AND SATURDAY LOOK TO BE THE WARMEST DAYS WITH MANY LOCATIONS REACHING INTO THE 70S. A PASSING SHORTWAVE TROUGH MAY FORCE A MODEST COOL SURGE INTO THE AREA BY SUNDAY BUT AT THIS POINT IT LOOKS LIKE TEMPERATURES WILL STILL BE ABLE TO RISE TO ABOVE NORMAL LEVELS. BRB && .AMA WATCHES/WARNINGS/ADVISORIES... TX...NONE. OK...NONE. && $$ 14/09
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
500 PM CST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 204 PM CST MON FEB 2 2015 HIGHLIGHTS/CONCERNS... 1. WILL IT STAY DRY TONIGHT 2. TEMPERATURES TONIGHT 3. INCOMING SNOW FOR TUESDAY...IMPACTING THE EVENING COMMUTE. CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED NORTHWEST FLOW FROM THE PACIFIC NORTHWEST INTO THE SOUTHEASTERN U.S.. 2 SHORTWAVES OF NOTE WITHIN THIS FLOW WERE OVER SOUTH DAKOTA AND COMING INTO CENTRAL BRITISH COLUMBIA. THE SHORTWAVE OVER SOUTH DAKOTA...DESPITE LOOKING DECENT ON WATER VAPOR...HAS BEEN PRODUCING NOTHING MORE THAN SOME MID AND HIGH CLOUDS. THIS IS DUE TO PLENTIFUL DRY AIR PRESENT ACROSS THE DAKOTAS INTO THE FORECAST AREA SEEN ON 12Z SOUNDINGS. PRECIPITABLE WATER VALUES AT 12Z WERE GENERALLY 0.05-0.10 INCHES...OR AROUND 30 PERCENT OF NORMAL. THIS DRY AIR WAS ALSO COLD WITH 925MB TEMPS BETWEEN -14 AND -17C AT 18Z TODAY PER RAP ANALYSIS FROM THE EASTERN DAKOTAS EASTWARD INTO MICHIGAN. THUS...DESPITE SUNSHINE...THE FRESH SNOW COVER AND THE COLD AIR ALOFT HAS ONLY ALLOWED TEMPERATURES TO REACH INTO THE SINGLE DIGITS TO TEENS ABOVE ZERO...COLDEST WEST OF HIGHWAY 52 WHERE ALBEDO VALUES ARE VERY HIGH. LAST ITEM OF NOTE WAS A POTENT TROUGH DROPPING SOUTH THROUGH THE NORTHWEST TERRITORIES...WHICH IS PROGGED TO COME THROUGH THE REGION LATE WEDNESDAY. FOR TONIGHT...THE SHORTWAVE EVIDENT OVER THE DAKOTAS HAS EVEN TRENDED A LITTLE MORE SOUTHWEST COMPARED TO YESTERDAY...HEADING ACROSS NORTHEAST MISSOURI BY 04Z. GIVEN THE DRY AIR MASS IN PLACE AND THE TRACK OF THE SHORTWAVE...FEEL CONFIDENT TO KEEP THE FORECAST DRY. THIS IS IN LINE TOO WITH ALL MODEL QPF OUTPUT. STILL WE SHOULD SEE A PERIOD OF MID AND HIGH CLOUDS THROUGH THE EARLY OVERNIGHT. ITS POSSIBLE WE COULD HAVE A PERIOD OF CLEARING BETWEEN 08-10Z... PROVIDED ECMWF 925MB RH FIELD IS CORRECT IN NOT SHOWING ANY LOW CLOUDS IN THE WAKE OF THE SHORTWAVE...BEFORE MORE CIRRUS MOVES IN. IF THIS CLEAR PERIOD MATERIALIZES...WINDS ARE RELATIVELY LIGHT SO TEMPERATURES COULD TANK EASILY BELOW ZERO. WITH ANTICYCLONIC LOW LEVEL FLOW...FEEL THE CLEARING IS MORE LIKELY...AND THUS LOWERED LOWS SOME TOWARDS THE COLDER ECMWF/CANADIAN GUIDANCE. FOR TUESDAY. THE SHORTWAVE CURRENTLY COMING INTO BRITISH COLUMBIA IS PROGGED TO REACH NORTHERN IOWA BY 00Z WEDNESDAY. ALTHOUGH THIS SHORTWAVE IS WEAKER THAN THE ONE THAT COMES THROUGH TONIGHT...THERE IS A LONGER PERIOD TO BRING IN MOISTURE. PRECIPITABLE WATER CLIMBS TO 0.3 TO 0.4 INCHES...WHICH IS MUCH CLOSER TO NORMAL. ADDITIONALLY...MODELS SHOW A FAIRLY STRONG FRONTOGENESIS AND FRONTOLYSIS COUPLET BETWEEN 900-700MB...WITH ITS FORCING CORRELATED NICELY WITH THE DENDRITIC GROWTH ZONE. THUS...FEEL VERY CONFIDENT OF SEEING A FLUFFY SNOW BAND SET UP. TRACK...GOOD MODEL CONSENSUS REMAINS FOR LOCATIONS SOUTHWEST OF I-94 TO BE IMPACTED...AND IT COULD EVEN REACH AS FAR NORTH AS TAYLOR COUNTY. SOME DIFFERENCES FOR THE MOST ACCUMULATION...EITHER AROUND I- 90 OR THROUGH NORTHEAST IOWA...AND FOR NOW TOOK A COMPROMISE. TIMING...SOME SNOW COULD ARRIVE FROM THE WEST INTO LOCATIONS WEST OF THE MS RIVER BY 18Z...BUT MUCH OF IT SHOULD FALL BETWEEN 18-00Z. THE SNOW SHOULD EXIT THE SOUTHEAST END OF THE FORECAST AREA BY 03Z. AMOUNTS...MAXIMUM MODEL QPF IN THE 0.15 TO 0.2 RANGE SEEMS REASONABLE GIVEN THE FORCING AND PRECIPITABLE WATER...WHICH COULD SUPPORT BASED ON THE FLUFFY SNOW IDEA UPWARDS OF A LOCALIZED 3 INCHES. MOST ACCUMULATIONS SHOULD FALL BETWEEN 1-2 INCHES... THOUGH...DUE TO THE QUICK NATURE OF THE FORCING. ALTHOUGH THE AMOUNTS ARE BELOW ADVISORY CRITERIA...THE TIMING COMING THROUGH IMPACTING THE EVENING COMMUTE MAY WARRANT ONE IN LATER FORECASTS...ESPECIALLY IF QPF INCREASES. RIGHT NOW HAVE CONTINUED TO ADDRESS IN OTHER SERVICES. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 204 PM CST MON FEB 2 2015 HIGHLIGHTS/CONCERNS... 1. TRACK OF ACCUMULATING SNOW ON WEDNESDAY 2. LOWS/WIND CHILLS WEDNESDAY NIGHT AND POSSIBLE ADVISORY NEED 3. BRIEF WARM UP TOWARDS NORMAL FOR FRIDAY INTO SATURDAY 4. POTENTIAL FOR MORE ACCUMULATING SNOW THIS WEEKEND 5. ANOTHER COLD SHOT FOR LATE IN THE WEEKEND THE CURRENT UPPER TROUGH OVER THE NORTHWEST TERRITORIES IS PROGGED TO DROP DOWN INTO THE REGION AROUND WEDNESDAY EVENING. AS THIS TROUGH APPROACHES ALL MODELS ARE DEVELOPING A WEST TO EAST FRONTOGENETIC BAND OF ACCUMULATING SNOW FOR WEDNESDAY. THE TRACK OF THIS BAND RANGES FROM SOUTH OF I-80 IN THE 02.12Z NAM/GFS WHICH WOULD BE DRY FOR OUR AREA...AROUND I-80 FROM THE 02.12Z CANADIAN WITH A BRIEF BRUSH OF LIGHT SNOW ACROSS THE FAR SOUTH...AND AROUND TO JUST NORTH OF I-80 FROM THE 02.00Z/12Z ECMWF WHICH COULD BRING SNOW AS FAR NORTH AS I-90. HAVE TO MAINTAIN SOME LOW CHANCES OF PRECIPITATION SOUTH OF I-90 DUE TO THE ECMWF/CANADIAN. HOPEFULLY LATER MODEL RUNS WILL COME INTO BETTER AGREEMENT. THE MORE BULLISH ECMWF WOULD YIELD 1-2 INCHES OF ACCUMULATION SOUTH OF I-90. MUCH COLDER AIR MOVES IN FOR WEDNESDAY NIGHT WITH THE UPPER TROUGH...AS 925MB TEMPS FALL TO -16 TO -20C BY 12Z THURSDAY. IT DOES LOOK BRISK DURING THE EVENING...BUT ARCTIC HIGH PRESSURE MOVING IN OVERNIGHT WILL ALLOW WINDS TO BECOME LIGHT. EXPECT THE LIGHTENING WINDS TO HELP THE WIND CHILL SITUATION AND WE MAY BE ABLE TO SQUEAK BY WITHOUT AN ADVISORY. HOWEVER...TEMPERATURES WILL TANK AS SKIES CLEAR AND WINDS DIMINISH. READINGS SIMILAR TO THIS MORNING ARE LIKELY. A NORTHWEST FLOW LOOKS TO PERSIST IN THE WAKE OF THE WEDNESDAY NIGHT UPPER TROUGH AND INTO EARLY NEXT WEEK. THIS FLOW SEPARATES AN ARCTIC COLD AIRMASS ACROSS MUCH OF CANADA AND WARMER AIR ACROSS THE WESTERN U.S. INTO THE CENTRAL PLAINS. SMALL PERTURBATIONS/SHORTWAVES MIGRATING THROUGH THE NORTHWEST FLOW WILL MODULATE HOW MUCH OF THE WARMER AND COLDER AIR ENTERS THE FORECAST AREA. TAKE FOR EXAMPLE FRIDAY INTO SATURDAY MORNING WHERE THE 02.12Z GFS BRINGS 850MB TEMPS UP TO 2-9C ABOVE...WITH THE ECMWF NOT TOO DISSIMILAR. SNOWPACK AND LOWER SUN ANGLE PREVENTS MIXING TO 850MB...BUT STILL WE SHOULD SEE HIGHS CLIMB AT LEAST BACK TOWARDS NORMAL. ALSO FOR SATURDAY INTO SATURDAY NIGHT...A FRONTOGENETIC BAND OF SNOW LOOKS TO DROP SOUTH INTO THE FORECAST AREA. THIS FEATURE HAS BEEN CONSISTENT BUT PLACEMENT ISSUES/TIMING EXIST...SO PRECIPITATION CHANCES IN THE 30- 50 RANGE PERSIST. THE BAND COULD PERSIST INTO SUNDAY PER 02.12Z GFS SO STILL HAVE LOWER CHANCES. IN THE WAKE OF THIS SNOW...THERE ARE SUGGESTIONS FOR A DEEPER TROUGH TO FORM OVER THE EASTERN U.S. FOR SUNDAY INTO MONDAY...ALLOWING SOME OF THE ARCTIC AIR TO OUR NORTH TO FLOW IN. THUS...COLDER CONDITIONS ARE FORECAST DURING THIS TIME. && .AVIATION...(FOR THE 00Z TAFS THROUGH 00Z TUESDAY EVENING) ISSUED AT 500 PM CST MON FEB 2 2015 SHORTWAVE TROUGH CURRENTLY TAKING AIM ON IA EARLY THIS EVENING...BUT ONLY SOME MID/HIGH LEVEL CLOUDS WITH IT. JUST TOO DRY AT THE SFC FOR PCPN...PER SFC OBS AND BUFKIT SOUNDINGS. NAM IS BULLISH ON DEVELOPING NEAR SFC SATURATION OVERNIGHT...BUT WITHOUT ANY REAL- TIME SUPPORT...WILL KEEP ANY CIGS VFR FOR NOW. LOOKS LIKE A BREAK IN THE CLOUDS OVERNIGHT INTO TUE MORNING...BEFORE ANOTHER SHORTWAVE SPINS INTO THE AREA. SATURATION IS BETTER WITH THIS SYSTEM...ENOUGH SO THAT A 6-10 HOUR PERIOD OF -SN LOOKS LIKELY FOR KRST/KLSE. AMOUNTS UP TO 2 INCHES EXPECTED AT THE MOMENT. MVFR CIGS SHOULD ACCOMPANY THE SNOW...WITH SOME IFR POSSIBLE AT KRST. VSBYS FROM 1-2SM ALSO ANTICIPATED WITH THE HEAVIER SNOWFALL. START TIME LOOKS CLOSE TO 18Z FOR KRST...AND 19-20Z AT KLSE. SNOW SHOULD CLEAR KRST BY 03Z AND KLSE TOWARD 05Z. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...RIECK
AREA FORECAST DISCUSSION
NWS LA CROSSE WI
204 PM CST MON FEB 2 2015 .SHORT TERM...(THIS EVENING THROUGH TUESDAY) ISSUED AT 204 PM CST MON FEB 2 2015 HIGHLIGHTS/CONCERNS... 1. WILL IT STAY DRY TONIGHT 2. TEMPERATURES TONIGHT 3. INCOMING SNOW FOR TUESDAY...IMPACTING THE EVENING COMMUTE. CURRENTLY AS OF 20Z...WATER VAPOR LOOP AND RAP 500MB HEIGHT ANALYSIS SHOWED NORTHWEST FLOW FROM THE PACIFIC NORTHWEST INTO THE SOUTHEASTERN U.S.. 2 SHORTWAVES OF NOTE WITHIN THIS FLOW WERE OVER SOUTH DAKOTA AND COMING INTO CENTRAL BRITISH COLUMBIA. THE SHORTWAVE OVER SOUTH DAKOTA...DESPITE LOOKING DECENT ON WATER VAPOR...HAS BEEN PRODUCING NOTHING MORE THAN SOME MID AND HIGH CLOUDS. THIS IS DUE TO PLENTIFUL DRY AIR PRESENT ACROSS THE DAKOTAS INTO THE FORECAST AREA SEEN ON 12Z SOUNDINGS. PRECIPITABLE WATER VALUES AT 12Z WERE GENERALLY 0.05-0.10 INCHES...OR AROUND 30 PERCENT OF NORMAL. THIS DRY AIR WAS ALSO COLD WITH 925MB TEMPS BETWEEN -14 AND -17C AT 18Z TODAY PER RAP ANALYSIS FROM THE EASTERN DAKOTAS EASTWARD INTO MICHIGAN. THUS...DESPITE SUNSHINE...THE FRESH SNOW COVER AND THE COLD AIR ALOFT HAS ONLY ALLOWED TEMPERATURES TO REACH INTO THE SINGLE DIGITS TO TEENS ABOVE ZERO...COLDEST WEST OF HIGHWAY 52 WHERE ALBEDO VALUES ARE VERY HIGH. LAST ITEM OF NOTE WAS A POTENT TROUGH DROPPING SOUTH THROUGH THE NORTHWEST TERRITORIES...WHICH IS PROGGED TO COME THROUGH THE REGION LATE WEDNESDAY. FOR TONIGHT...THE SHORTWAVE EVIDENT OVER THE DAKOTAS HAS EVEN TRENDED A LITTLE MORE SOUTHWEST COMPARED TO YESTERDAY...HEADING ACROSS NORTHEAST MISSOURI BY 04Z. GIVEN THE DRY AIR MASS IN PLACE AND THE TRACK OF THE SHORTWAVE...FEEL CONFIDENT TO KEEP THE FORECAST DRY. THIS IS IN LINE TOO WITH ALL MODEL QPF OUTPUT. STILL WE SHOULD SEE A PERIOD OF MID AND HIGH CLOUDS THROUGH THE EARLY OVERNIGHT. ITS POSSIBLE WE COULD HAVE A PERIOD OF CLEARING BETWEEN 08-10Z... PROVIDED ECMWF 925MB RH FIELD IS CORRECT IN NOT SHOWING ANY LOW CLOUDS IN THE WAKE OF THE SHORTWAVE...BEFORE MORE CIRRUS MOVES IN. IF THIS CLEAR PERIOD MATERIALIZES...WINDS ARE RELATIVELY LIGHT SO TEMPERATURES COULD TANK EASILY BELOW ZERO. WITH ANTICYCLONIC LOW LEVEL FLOW...FEEL THE CLEARING IS MORE LIKELY...AND THUS LOWERED LOWS SOME TOWARDS THE COLDER ECMWF/CANADIAN GUIDANCE. FOR TUESDAY. THE SHORTWAVE CURRENTLY COMING INTO BRITISH COLUMBIA IS PROGGED TO REACH NORTHERN IOWA BY 00Z WEDNESDAY. ALTHOUGH THIS SHORTWAVE IS WEAKER THAN THE ONE THAT COMES THROUGH TONIGHT...THERE IS A LONGER PERIOD TO BRING IN MOISTURE. PRECIPITABLE WATER CLIMBS TO 0.3 TO 0.4 INCHES...WHICH IS MUCH CLOSER TO NORMAL. ADDITIONALLY...MODELS SHOW A FAIRLY STRONG FRONTOGENESIS AND FRONTOLYSIS COUPLET BETWEEN 900-700MB...WITH ITS FORCING CORRELATED NICELY WITH THE DENDRITIC GROWTH ZONE. THUS...FEEL VERY CONFIDENT OF SEEING A FLUFFY SNOW BAND SET UP. TRACK...GOOD MODEL CONSENSUS REMAINS FOR LOCATIONS SOUTHWEST OF I-94 TO BE IMPACTED...AND IT COULD EVEN REACH AS FAR NORTH AS TAYLOR COUNTY. SOME DIFFERENCES FOR THE MOST ACCUMULATION...EITHER AROUND I- 90 OR THROUGH NORTHEAST IOWA...AND FOR NOW TOOK A COMPROMISE. TIMING...SOME SNOW COULD ARRIVE FROM THE WEST INTO LOCATIONS WEST OF THE MS RIVER BY 18Z...BUT MUCH OF IT SHOULD FALL BETWEEN 18-00Z. THE SNOW SHOULD EXIT THE SOUTHEAST END OF THE FORECAST AREA BY 03Z. AMOUNTS...MAXIMUM MODEL QPF IN THE 0.15 TO 0.2 RANGE SEEMS REASONABLE GIVEN THE FORCING AND PRECIPITABLE WATER...WHICH COULD SUPPORT BASED ON THE FLUFFY SNOW IDEA UPWARDS OF A LOCALIZED 3 INCHES. MOST ACCUMULATIONS SHOULD FALL BETWEEN 1-2 INCHES... THOUGH...DUE TO THE QUICK NATURE OF THE FORCING. ALTHOUGH THE AMOUNTS ARE BELOW ADVISORY CRITERIA...THE TIMING COMING THROUGH IMPACTING THE EVENING COMMUTE MAY WARRANT ONE IN LATER FORECASTS...ESPECIALLY IF QPF INCREASES. RIGHT NOW HAVE CONTINUED TO ADDRESS IN OTHER SERVICES. .LONG TERM...(TUESDAY NIGHT THROUGH MONDAY) ISSUED AT 204 PM CST MON FEB 2 2015 HIGHLIGHTS/CONCERNS... 1. TRACK OF ACCUMULATING SNOW ON WEDNESDAY 2. LOWS/WIND CHILLS WEDNESDAY NIGHT AND POSSIBLE ADVISORY NEED 3. BRIEF WARM UP TOWARDS NORMAL FOR FRIDAY INTO SATURDAY 4. POTENTIAL FOR MORE ACCUMULATING SNOW THIS WEEKEND 5. ANOTHER COLD SHOT FOR LATE IN THE WEEKEND THE CURRENT UPPER TROUGH OVER THE NORTHWEST TERRITORIES IS PROGGED TO DROP DOWN INTO THE REGION AROUND WEDNESDAY EVENING. AS THIS TROUGH APPROACHES ALL MODELS ARE DEVELOPING A WEST TO EAST FRONTOGENETIC BAND OF ACCUMULATING SNOW FOR WEDNESDAY. THE TRACK OF THIS BAND RANGES FROM SOUTH OF I-80 IN THE 02.12Z NAM/GFS WHICH WOULD BE DRY FOR OUR AREA...AROUND I-80 FROM THE 02.12Z CANADIAN WITH A BRIEF BRUSH OF LIGHT SNOW ACROSS THE FAR SOUTH...AND AROUND TO JUST NORTH OF I-80 FROM THE 02.00Z/12Z ECMWF WHICH COULD BRING SNOW AS FAR NORTH AS I-90. HAVE TO MAINTAIN SOME LOW CHANCES OF PRECIPITATION SOUTH OF I-90 DUE TO THE ECMWF/CANADIAN. HOPEFULLY LATER MODEL RUNS WILL COME INTO BETTER AGREEMENT. THE MORE BULLISH ECMWF WOULD YIELD 1-2 INCHES OF ACCUMULATION SOUTH OF I-90. MUCH COLDER AIR MOVES IN FOR WEDNESDAY NIGHT WITH THE UPPER TROUGH...AS 925MB TEMPS FALL TO -16 TO -20C BY 12Z THURSDAY. IT DOES LOOK BRISK DURING THE EVENING...BUT ARCTIC HIGH PRESSURE MOVING IN OVERNIGHT WILL ALLOW WINDS TO BECOME LIGHT. EXPECT THE LIGHTENING WINDS TO HELP THE WIND CHILL SITUATION AND WE MAY BE ABLE TO SQUEAK BY WITHOUT AN ADVISORY. HOWEVER...TEMPERATURES WILL TANK AS SKIES CLEAR AND WINDS DIMINISH. READINGS SIMILAR TO THIS MORNING ARE LIKELY. A NORTHWEST FLOW LOOKS TO PERSIST IN THE WAKE OF THE WEDNESDAY NIGHT UPPER TROUGH AND INTO EARLY NEXT WEEK. THIS FLOW SEPARATES AN ARCTIC COLD AIRMASS ACROSS MUCH OF CANADA AND WARMER AIR ACROSS THE WESTERN U.S. INTO THE CENTRAL PLAINS. SMALL PERTURBATIONS/SHORTWAVES MIGRATING THROUGH THE NORTHWEST FLOW WILL MODULATE HOW MUCH OF THE WARMER AND COLDER AIR ENTERS THE FORECAST AREA. TAKE FOR EXAMPLE FRIDAY INTO SATURDAY MORNING WHERE THE 02.12Z GFS BRINGS 850MB TEMPS UP TO 2-9C ABOVE...WITH THE ECMWF NOT TOO DISSIMILAR. SNOWPACK AND LOWER SUN ANGLE PREVENTS MIXING TO 850MB...BUT STILL WE SHOULD SEE HIGHS CLIMB AT LEAST BACK TOWARDS NORMAL. ALSO FOR SATURDAY INTO SATURDAY NIGHT...A FRONTOGENETIC BAND OF SNOW LOOKS TO DROP SOUTH INTO THE FORECAST AREA. THIS FEATURE HAS BEEN CONSISTENT BUT PLACEMENT ISSUES/TIMING EXIST...SO PRECIPITATION CHANCES IN THE 30- 50 RANGE PERSIST. THE BAND COULD PERSIST INTO SUNDAY PER 02.12Z GFS SO STILL HAVE LOWER CHANCES. IN THE WAKE OF THIS SNOW...THERE ARE SUGGESTIONS FOR A DEEPER TROUGH TO FORM OVER THE EASTERN U.S. FOR SUNDAY INTO MONDAY...ALLOWING SOME OF THE ARCTIC AIR TO OUR NORTH TO FLOW IN. THUS...COLDER CONDITIONS ARE FORECAST DURING THIS TIME. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z TUESDAY AFTERNOON) ISSUED AT 1142 AM CST MON FEB 2 2015 A SHORT WAVE TROUGH...CURRENTLY OVER NORTHWEST MINNESOTA AND THE DAKOTAS...WILL MOVE QUICKLY SOUTHEAST ACROSS THE AREA THIS AFTERNOON AND EVENING. WITH A VERY DRY AIR MASS IN PLACE...ONLY EXPECTING CEILINGS TO DROP DOWN INTO THE 8 TO 12K RANGE. SKIES WILL BRIEFLY CLEAR OVERNIGHT AND THEN ANOTHER SHORT WAVE TROUGH...CURRENTLY LOCATED OVER NORTHERN ROCKIES... WILL BRING ANOTHER ROUND OF VFR CLOUDS. CEILINGS WILL LOWER FROM AROUND 12-15K FEET TO 5-7K FEET. THE NAM SOUNDINGS SUGGEST THAT THE CEILINGS COULD POTENTIALLY BECOME MVFR AFTER 03.08Z. HOWEVER JUST NOT SEEING THIS UPSTREAM...SO TRENDED THE FORECAST TOWARD THE ECMWF AND GFS. && .ARX WATCHES/WARNINGS/ADVISORIES... WI...NONE. MN...NONE. IA...NONE. && $$ SHORT TERM...AJ LONG TERM...AJ AVIATION...BOYNE