Forecast Discussions mentioning any of "HRRR" "RAP" "RR" "RUC13" "RUC" received at GSD on 01/05/14


AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
353 PM MST FRI JAN 3 2014 .SHORT TERM...UPPER TROUGH STILL MOVING INTO NORTHERN GREAT BASIN...BEGINNING TO SEE SOME INCREASE IN MOISTURE ACROSS THE MOUNTAINS...THOUGH LOOKS TO BE ABOVE MOUNTAIN TOP. NO PRECIPITATION CURRENTLY ACROSS MOUNTAINS...CLOSEST ACROSS SOUTHWEST WYOMING AND NORTHERN UTAH. WINDS A BIT GUSTY IN AND NEAR FOOTHILLS AND ACROSS THE HIGHER MOUNTAINS WITH MIXING AND INCREASING NORTHWEST FLOW ALOFT AHEAD OF TROUGH. WESTERLY WINDS HAVE SPREAD AS FAR EAST AS DIA WHICH HELPED TO WARM TEMPERATURES TO NEAR 60. TROUGH WILL CONTINUE TO MOVE ACROSS THE NORTHERN GREAT BASIN SOUTHWARD TOWARD COLORADO THIS EVENING AND INTO WESTERN COLORADO OVERNIGHT. FLOW ALOFT TO BECOME A BIT MORE WESTERLY WITH INCREASING MOISTURE ACROSS MOUNTAINS. OROGRAPHICS WILL IMPROVE BY 03Z ALONG WITH INCREASING MID LEVEL QG ASCENT AS JET SAGS SOUTHWARD TOWARD COLORADO. SHOULD SEE SOME SNOW BEGIN TO DEVELOP BY THE EVENING...ESPECIALLY ACROSS ZONE 31...THEN GRADUALLY BECOME WIDESPREAD THROUGH THE EVENING WITH IMPROVING OROGRAPHICS AND LIFT. MODELS SHOW AN INITIAL SHORTWAVE MOVING ACROSS THE MOUNTAINS AROUND 06Z...WHICH WILL HELP WITH THE SNOWFALL. ALSO THE APPROACHING JET WILL PROVIDE ADDITIONAL VERTICAL MOTION. GUSTY WINDS WILL CREATE AREAS OF BLOWING SNOW BY MIDNIGHT...ESPECIALLY ACROSS THE HIGHER MOUNTAIN PASSES. CURRENT HILITES STILL LOOK REASONABLE...WITH THE HEAVIER AMOUNTS ACROSS ZONE 31. DID DELAY THE ONSET OF THE ADVISORIES FOR ZONES 30..32..33 AND 34 UNTIL 03Z BASED ON CURRENT CONDITIONS. ACROSS FOOTHILLS AND PLAINS...GUSTY WINDS WILL PERSIST INTO THE EVENING IN AND NEAR FOOTHILLS BEFORE DECREASING. COLD FRONT ASSOCIATED WITH THE UPPER TROUGH STILL EXPECTED TO MOVE OUT OF WYOMING AROUND 06Z AND ACROSS THE DENVER AREA BY 09Z. UPSLOPE WILL THEN DEVELOP AROUND 12Z. LOW LEVEL MOISTURE TO GRADUALLY INCREASE WITH A CHANCE OF LIGHT SNOW IN AND NEAR THE FOOTHILLS BY MORNING AS LIFT INCREASES. ON SATURDAY...UPPER TROUGH WILL MOVE ACROSS THE AREA THROUGH THE DAY. THE COMBINATION OF GOOD OROGRAPHICS AND MID LEVEL QG ASCENT WITH JET IN VICINITY WILL CONTINUE TO PROVIDE SNOW FOR THE MOUNTAINS. WILL CONTINUE WITH THE CURRENT HILITES THROUGH THE AFTERNOON. FOR FOOTHILLS AND PLAINS...INCREASING UPSLOPE AND MID LEVEL ASCENT WILL BRING A DECENT SHOT OF SNOW TO MOST LOCATIONS...MAINLY IN AND NEAR FOOTHILLS. LATEST MODELS STILL SHOWING AMOUNTS IN THE 1 TO 4 INCH RANGE. NAM ON THE LOW END...GFS THE HIGHER END ACROSS THE DENVER AREA SOUTH OVER THE PALMER DIVIDE. THERE IS STILL SOME CHANCE FOR A BAND OF HEAVIER SNOW SETTING UP SOMEWHERE ACROSS THE AREA BY THE AFTERNOON AND COULD HELP PRODUCE MORE SNOW. FOR NOW WILL CONTINUE WITH THE LOWER AMOUNTS AND WILL WAIT TO SEE WHAT DEVELOPS BEFORE ISSUING ANY ADVISORIES. AIRMASS TO BE COLDER... WITH TEMPERATURES STRUGGLING TO GET TO THE MIDDLE 20S ACROSS PLAINS. .LONG TERM...THE AMS WILL BECOME INCREASINGLY SUBSIDENT SATURDAY NIGHT AS THE STORM SYSTEM MOVES TO THE EAST. A STRONG NORTHWESTERLY FLOW WILL BE OVER THE STATE ON SUNDAY WITH THE UPPER LEVEL JETSTREAM OVER COLORADO. A WEAK DISTURBANCE EMBEDDED IN THE FLOW ALOFT WILL BRUSH ACROSS NORTHEAST COLORADO AROUND 00Z MONDAY. WITH THE JET OVERHEAD...THERE IS THE POTENTIAL FOR SOME BANDED SNOWFALL OVER THE NORTHEAST PLAINS...BUT MDLS NOT DEVELOPING MUCH QPF AT THIS TIME SO WL STICK TO SLGT CHC POPS. IN THE MOUNTAINS AND FOOTHILLS...GUSTY NORTHWEST WINDS SO WL ADD AREAS OF BLOWING SNOW TO THE GRIDS. OVERALL SNOW AMOUNTS WILL BE LIGHT IN THE MOUNTAINS DUE TO INCREASING STABILITY. A SECONDARY SURGE OF COLD AIR SUNDAY EVENING...WL KEEP THE NORTHEAST PLAINS LOCKED IN THE FREEZER THROUGH MONDAY. THE FLOW ALOFT WILL WEAKEN AND BECOME MORE WESTERLY BY TUESDAY AS A RIDGE OF HIGH PRESSURE BUILDS IN FROM THE WEST. TEMPERATURES WILL MODIFY THROUGH MID WEEK. A WEAK SYSTEM MAY MOVE ACROSS COLORADO ON WEDNESDAY BUT SNOWFALL WILL LIKELY BE CONFINED TO THE MOUNTAIN AREAS. IT WILL BE DRY AGAIN ON THURSDAY WITH A SHORT WAVE RIDGE OVER COLORADO...FOLLOWED BY ANOTHER POTENTIAL TROUGH THURSDAY NIGHT INTO FRIDAY. FOR NOW WL KEEP THE MENTION OF SNOW CONFINED TO THE MOUNTAINS FOR THE END OF NEXT WEEK. && .AVIATION...WESTERLY WINDS CONTINUE ACROSS AREA AIRPORTS...WITH GUSTS TO 35 KTS AT BJC. WINDS STILL EXPECTED TO GRADUALLY WEAKEN THROUGH THE EVENING. LATEST RAP INDICATING WINDS SHIFTING TO THE NORTHWEST BY 02Z. THERE IS A CHANCE THAT DRAINAGE WINDS COULD DEVELOP AT KDEN AND KAPA DURING THE EVENING BEFORE SHIFTING TO THE NORTHWEST AFTER 06Z. WILL TREND THE TAFS IN THAT DIRECTION. MOISTURE TO GRADUALLY INCREASE THROUGH EVENING AND OVERNIGHT...WITH CEILINGS ABOVE 10000 FEET AGL. FRONT STILL EXPECTED TO MOVE ACROSS THE DENVER AREA AROUND 09Z WITH GUSTY NORTHERLY WINDS. CEILINGS WILL GRADUALLY LOWER AS UPSLOPE DEVELOPS BY 12Z ALONG WITH AREAS OF LIGHT SNOW. THE SNOW WILL CONTINUE THROUGH THE DAY SATURDAY WITH IFR CONDITIONS PREVAILING. CONDITIONS TO GRADUALLY IMPROVE AFTER 00Z AS UPSLOPE WEAKENS. SNOW ACCUMULATION OF 2 TO 4 INCHES STILL EXPECTED FOR AREA AIRPORTS. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM MST SUNDAY FOR COZ033-034. WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM MST SATURDAY FOR COZ030-032. WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 5 AM MST SUNDAY FOR COZ031. && $$ SHORT TERM...D-L LONG TERM....COOPER AVIATION...D-L
AREA FORECAST DISCUSSION
NWS DENVER/BOULDER CO
958 AM MST FRI JAN 3 2014 .UPDATE... && .SHORT TERM...MIXING HAS COMMENCED IN AND NEAR FOOTHILLS WITH GUSTY WESTERLY WINDS MOST AREAS. GRADIENT ACROSS STATE FROM GRAND JUNCTION TO DENVER HAS INCREASED TO 10.27 MB. SOME GUSTS TO 40 MPH BEING REPORTED AT KBJC AS WELL AS ALONG THE FOOTHILLS OF JEFFERSON COUNTY. SHOULD SEE WINDS CONTINUE TO INCREASE IN AND NEAR FOOTHILLS AS WELL AS ACROSS THE MOUNTAINS THROUGH THE AFTERNOON AHEAD OF APPROACHING UPPER TROUGH AND JET. LATEST RAP CROSS SECTIONS SHOW CROSS MOUNTAIN FLOW INCREASING TO AROUND 60 KTS AT MOUNTAIN TOP BY 00Z. MODELS KEEP THE STRONGEST WINDS IN AND NEAR MOUNTAIN TOP THROUGH THE EVENING. SO NOT EXPECTING WINDS TO EXCEED HIGH WIND CRITERIA. STILL...WOULD SUSPECT THERE WILL BE SOME GUSTS TO 60 MPH ACROSS THE RIDGES AS WELL AS WIND PRONE AREAS OF THE FOOTHILLS. WILL BOOST THE WINDS A BIT IN THE GRIDS THROUGH THIS EVENING IN AND NEAR FOOTHILLS. UPPER TROUGH STILL MOVING INTO NORTHERN GREAT BASIN WITH SOME MID AND HIGH LEVEL MOISTURE SPREADING ACROSS UTAH AND WESTERN WYOMING. MOISTURE WILL BE GRADUALLY INCREASING ACROSS THE MOUNTAINS THROUGH THE DAY...THOUGH CROSS SECTIONS KEEP MOISTURE ABOVE MOUNTAIN TOP. LATEST RAP SHOWS SOME QPF ACROSS ZONE 31 AROUND 00Z. WILL BE BACKING OFF ON THE CHANCES FOR SNOW THIS AFTERNOON FOR THE MOUNTAINS. MOISTURE TO THEN DEEPEN THIS EVENING AS TROUGH MOVES INTO THE GREAT BASIN AND OROGRAPHICS IMPROVE. SHOULD BE A GOOD SHOT OF SNOW FOR THE MOUNTAINS AND HIGH VALLEYS OVERNIGHT INTO SATURDAY. HILITES LOOK FINE. TIMING OKAY FOR NOW...AS SNOW SHOULD BE ON THE INCREASE AFTER 00Z. .AVIATION...GUSTY WESTERLY WINDS ONGOING AT KBJC WITH GUSTS TO 35 KTS. SOUTHWESTERLIES ONGOING AT KDEN AND KAPA. THE WESTERLY WINDS WILL SPREAD EAST ACROSS THE AREA AROUND 20 OR 21Z WITH POSSIBLE GUSTS TO 22 KTS AT KDEN AND KAPA. WINDS TO THEN SHIFT TO THE NORTHWEST AROUND 01Z. CURRENT TAFS SHOW THIS TREND AND STILL LOOKS REASONABLE. WILL CONTINUE FOR THE UPCOMING ISSUANCE. SOME INCREASE IN MID AND HIGH LEVEL MOISTURE BY THE EVENING...CEILINGS TO REMAIN UNRESTRICTED. FRONT EXPECTED TO MOVE ACROSS AREA AROUND 09Z WITH GUSTY NORTHERLY WINDS. CEILINGS TO LOWER BY 11Z WITH SNOW DEVELOPING. SNOW TO CONTINUE THROUGH THE DAY SATURDAY WITH IFR CONDITIONS PREVAILING. AT THIS TIME...SNOW ACCUMULATIONS BY SATURDAY EVENING LOOK TO BE IN THE 2 TO 4 INCH RANGE. && .PREV DISCUSSION... /ISSUED 354 AM MST FRI JAN 3 2014/ SHORT TERM...WARM CONDITIONS ARE EXPECTED TODAY AS WESTERLY DOWNSLOPE WINDS CONTINUE AHEAD OF TONIGHTS PASSING UPPER LEVEL DISTURBANCE. WEST WINDS OVER THE WESTERN DENVER SUBURBS HAVE HELPED TO KEEP TEMPERATURES IN THE UPPER 30S TO MID 40S THIS MORNING. ELSEWHERE ON THE PLAINS...LOWS HAVE DROPPED AS LOW AS THE MID TEENS AND LOWER 20S. AFTER SUNRISE...THE AIRMASS SHOULD BECOME WELL MIXED WITH HIGHS WARMING TO THE MID AND UPPER 50S ACROSS NORTHEAST COLORADO. MOUNTAIN AREAS SHOULD SEE TEMPERATURES CLOSER TO SEASONAL NORMALS AS CLOUDS BEGIN INCREASING BY AFTERNOON. THE FOOTHILLS AND MOUNTAIN RIDGES SHOULD SEE GUSTY WINDS THROUGH THE DAY BECAUSE OF THE STRONG NORTHWEST FLOW IN PLACE OVER THE STATE. CROSS SECTIONS SHOW THAT THE HIGHEST WINDS ARE EXPECTED TO REMAIN OVER THE FOOTHILLS AND HIGHER TERRAIN. A FEW FAVORED LOCATIONS ON THE PLAINS MAY SEE SOME GUSTY WINDS AT TIMES...BUT NO HIGHLIGHTS ARE NECESSARY. TONIGHT WILL SEE BIG CHANGES SPREAD ACROSS THE FORECAST AREA FROM THE NORTHWEST AS A SHORT WAVE TROUGH MOVES OVER THE STATE. A STRONG COLD FRONT WILL ACCOMPANY THE UPPER LEVEL SYSTEM AND MOVE FROM THE WYOMING BORDER TO THE PALMER DIVIDE BETWEEN MIDNIGHT AND 6 AM. ALOFT...THE UPPER DISTURBANCE IS BEING DRIVEN BY A VERY STRONG JET WHICH WILL AID IN PRODUCING VERICAL MOTIONS AND BANDED PRECIPITATION FIELDS. MOUNTAIN AREAS SHOULD SEE OROGRAPHIC PRECIPITATION BEGINNING LATE IN THE AFTERNOON OR DURING THE EVENING. ONCE PRECIPITATION BEGINS IN THE MOUNTAINS...IT SHOULD CONTINUE FOR 24 TO 36 HOURS WITH SIGNIFICANT ACCUMULATIONS POSSIBLE. WILL ISSUE WINTER WEATHER ADVISORIES FOR ZONES 30...32...33 AND 34 AND A WINTER STORM WARNING FOR ZONE 31 WHERE AMOUNTS WILL BE HEAVIEST. LONG TERM...AN UPPER LEVEL TROUGH WILL MOVE SE ACROSS THE AREA ON SAT AS UPSLOPE FLOW DEVELOPS BEHIND A STG CDFNT. COMBINATION OF FAVORABLE MID LEVEL QG ASCENT THRU THE AFTN HOURS AND AXIS OF UPPER LEVEL JET SAGGING ACROSS THE AREA SHOULD LEAD TO A DECENT SHOT OF SNOW IN MOST AREAS. APPEARS BANDED PCPN WILL BE ALONG THE CO-WY BORDER AT 12Z AND THEN SHIFT SOUTHWARD THRU THE AFTN HOURS WITH BAND EXITING SRN AREAS OF CWA BY LATE AFTN. GFS IS CERTAINLY THE MOST AGGRESSIVE WITH SNOW AMOUNTS ON SAT WITH ADVISORY CRITERIA (3 TO 6 INCHES) OVER THE URBAN CORRIDOR EASTWARD ACROSS THE PLAINS WITHIN A 12 HOUR WINDOW WHILE THE OTHER MODELS ARE MORE IN THE 1 TO 3 INCH RANGE. IF BANDED PCPN DOES OCCUR AND MOISTURE DEPTH IS DEEPER THEN GFS MAY END BE CORRECT WITH SNOW AMOUNTS. HOWEVER FOR NOW WILL LET DAY SHIFT DECIDE IF AMOUNTS WILL REACH ADVISORY CRITERIA OVER NERN CO. IN THE MTNS AMOUNTS MAY REACH WARNING CRITERIA IN ZN 31 WITH HIGH END ADVISORY AMOUNTS IN ZNS 33 AND 34 THRU SAT NIGHT. WINDS WILL BE GUSTY AT TIMES AS WELL SO WILL SEE BLOWING SNOW OVER THE HIGHER PASSES. HIGHER VALLEYS IN ZNS 30 AND 32 MAY REACH ADVISORY CRITERIA AS WELL ON SAT DUE TO BANDED PCPN SO WILL INCLUDE THEM AS WELL. HIGHS ON SAT WILL STAY IN THE 20S OVER NERN CO. BY SAT NIGHT THE UPSLOPE FLOW WILL WEAKEN WITH MID LVL DESCENT OVER THE AREA. THUS SNOW CHANCES SHOULD DECREASE ACROSS NERN CO. IN THE MTNS OROGRAPHICS WILL REMAIN FAVORABLE SAT NIGHT ALTHOUGH STABILITY WILL INCREASE SO ADDITIONAL ACCUMULATIONS WILL GENERALLY STAY ON THE LIGHT SIDE. ON SUN STG NW FLOW ALOFT WILL REMAIN OVER THE AREA AS ANOTHER DISTURBANCE POSSIBLY AFFECTS THE AREA. OROGRAPHICS WILL REMAIN FAVORABLE IN THE MTNS HOWEVER MOISTURE DEPTH WILL DECREASE SOME SO LIGHT ACCUMULATIONS WILL CONTINUE WITH AREAS OF BLOWING SNOW. AT LOWER ELEVATIONS ANOTHER SHOT OF COLD AIR WILL MOVE INTO NERN CO SUN AFTN WITH UPSLOPE FLOW DEVELOPING ALONG WITH AN INCREASE IN MOISTURE. AS THE STG UPPER LEVEL JET MOVES ACROSS SUN AFTN INTO SUN EVENING THERE COULD BE ANOTHER PERIOD OF BANDED PCPN OVER PORTIONS OF NERN CO PROBABLY NORTH OF A DENVER TO LIMON LINE. SINCE THIS IS STILL PRETTY FAR OUT FOR NOW WILL JUST MENTION A SLIGHT CHC OF SNOW. HIGHS COULD END UP BEING COLDER THAN SAT OVER NERN CO AS READINGS MAY STRUGGLE TO GET ABV 20. FOR MON THE FLOW ALOFT WILL BEGIN TO WEAKEN AS A STG UPPER LEVEL TROUGH RESIDES OVER THE CENTRAL AND EASTERN US. CURRENT CROSS- SECTIONS SHOW MUCH DRIER AIR SPREADING ACROSS THE AREA SO WILL NOT MENTION ANY POPS. AS FAR AS HIGHS WILL KEEP READINGS IN THE 20S ALTHOUGH AREAS OVER THE FAR ERN PLAINS MAY STILL STRUGGLE TO GET ABV 20. BY TUE WNW FLOW ALOFT WILL CONTINUE WITH MODELS NOT SHOWING MUCH MOISTURE THRU THE AFTN HOURS SO WILL ONLY MENTION LOW POPS IN THE MTNS. HIGHS SHOULD BEGIN TO MODERATE OVER NERN CO WITH READINGS RISING BACK INTO THE 30S. FOR WED A WEAK UPPER LEVEL TROUGH MAY AFFECT THE AREA BRINGING A CHC OF SNOW TO THE MTNS. OVER NERN CO WILL KEEP FCST DRY WITH TEMPS NEAR SEASONAL LEVELS. AVIATION...KDEN AND KAPA SHOULD SEE A CONTINUATION OF SOUTHERLY WINDS THIS MORNING TRANSITIONING TO WESTERLY BY LATE MORNING AND EARLY AFTERNOON. SOME GUSTS TO ABOUT 20 KNOTS WILL BE POSSIBLE LATE IN THE AFTERNOON. AT KBJC...WEST WINDS HAVE ALREADY SPREAD ACROSS THE NORTHERN PARTS OF JEFFERSON COUNTY. WIND GUSTS UP TO 30 KNOTS WILL CONTINUE MUCH OF THE DAY. CEILINGS AND VISIBILITIES WILL REMAIN UNRESTRICTED THROUGH THIS EVENING. LATER TONIGHT... STILL EXPECT COLD FRONT TO MOVE ACROSS THE DENVER AREA AFTER 2 AM WITH LOWERING CEILINGS AND SNOWFALL DEVELOPING BY SUNRISE TOMORROW MORNING. IFR CONDITIONS AND ACCUMULATING SNOWFALL SHOULD BE EXPECTED ALL DAY SATURDAY. && .BOU WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 AM MST SUNDAY FOR COZ033-034. WINTER WEATHER ADVISORY FROM 5 PM THIS AFTERNOON TO 5 PM MST SATURDAY FOR COZ030-032. WINTER STORM WARNING FROM 5 PM THIS AFTERNOON TO 5 AM MST SUNDAY FOR COZ031. && $$ SHORT TERM...D-L LONG TERM....RPK AVIATION...D-L
AREA FORECAST DISCUSSION
NWS NEW YORK NY
624 AM EST FRI JAN 3 2014 .SYNOPSIS... A POTENT STORM SYSTEM TRACKS INTO THE CANADIAN MARITIMES AS ARCTIC HIGH PRESSURE BUILDS IN THROUGH TONIGHT. HIGH PRESSURE BUILDS OFFSHORE ON SATURDAY AHEAD OF A COLD FRONT MOVING ACROSS THE UPPER MIDWEST AND GREAT LAKES. A WAVE OF LOW PRESSURE THEN FORMS ALONG THE FRONT OVER THE TENNESSEE VALLEY ON SUNDAY...TRACKING NORTHEAST INTO EASTERN CANADA ON MONDAY. AS IT DOES SO...IT WILL SEND AN ARCTIC COLD FRONT THROUGH THE REGION IN THE MORNING. HIGH PRESSURE BUILDS TO THE SOUTH AND WEST OF THE REGION THROUGH MID NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 990 HPA LOW WAS LOCATED ABOUT 190 MILES SE OF KMTP AT 11Z. LOW LEVEL FRONTOGENETIC FORCING TO THE NW OF THE LOW PRODUCING SNOW BANDS ACROSS CENTRAL AND EASTERN CT AND LONG ISLAND...WITH LIGHTER SNOW TO THE WEST. SNOW WILL TAPER OFF FROM W TO E THIS MORNING BY AROUND 7 AM OVER FAR WESTERN ZONES 8-9AM AT NYC AND BY 10-11AM OVER FAR EASTERN ZONES. STILL ON TRACK FOR 8-12 INCHES ACROSS LONG ISLAND AND 6 TO 10 INCHES ELSEWHERE WITH LOCALLY HIGHER AMOUNTS. THERE IS STILL SOME INDICATION THAT COULD HAVE A LINGERING DEFORMATION BAND OVER EASTERN LONG ISLAND INTO EARLY AFTERNOON - BUT FOR NOW DO NOT THINK WILL ADD MUCH TO ACCUMULATION. WILL NEED TO MONITOR THIS FEATURE THOUGH - AS SOMETIMES THEY ARE GOOD FOR AN EXTRA INCH OR TWO OF SNOWFALL. EVEN AS SNOW SHUTS DOWN - STRONG N-NE WINDS GUSTING TO 30-45 MPH WILL CAUSING BLOWING OF THE DRY POWDERY SNOW AND VERY LOW WIND CHILLS - WITH VALUES 15 TO AROUND 20 BELOW ZERO ACROSS NORTHERN INTERIOR ZONES AND 5 TO AROUND 10 BELOW ELSEWHERE INTO THE EARLY AFTERNOON HOURS. AS A RESULT HAVE LEFT THE WINTER WEATHER HEADLINES AS IS. WINDS DIMINISH THIS AFTERNOON - WITH WIND CHILLS INCREASING TO FROM -10 TO AROUND 0. FOR HIGHS TODAY TOOK A BLEND OF MIXING DOWN FROM 925 HPA PER BUFKIT SOUNDINGS WITH NAM AND RUC 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT VALUES DURING THE TEENS TODAY - WITH MOST HIGHS FOR THE DAY REACHED JUST AFTER MIDNIGHT - AND THE WARMEST TEMPERATURES DURING THE DAYLIGHT HOURS LIKELY DURING THE MORNING HOURS. RECORD LOW TEMPERATURES AND RECORD LOW MAXIMUM TEMPERATURES ARE LIKELY TODAY AT SOME CLIMATE SITES. SEE THE CLIMATE SECTION OF THE AFD FOR DETAILS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... MAINLY CLEAR SKY CONDITIONS IN THE WAKE OF THE DEPARTING LOW COUPLED WITH SNOW COVER AND DIMINISHING WINDS WILL ALLOW FOR LOWS TO PLUMMET TONIGHT. LOWS WILL BE MAINLY FROM 5 ABOVE TO AROUND 10 BELOW - COLDEST ACROSS THE NORTHERN TIER. THIS AROUND 20-25 DEGREES BELOW NORMAL - AND CONSISTENT WITH TAKING THE LOWEST OF MAV/MET/NAM 2-METER TEMPERATURES AND BLENDING 2 PARTS OF THIS AND 1 PART OF A BLEND OF MAV/MET/NAM 2-METER TEMPERATURES. THIS INSURES THAT THE FORECAST LOWS ARE COLDER THAN A BLEND OF GUIDANCE - HOWEVER NAM 2-METER TEMPERATURES ACROSS THE INTERIOR SEEMED EXCESSIVELY COLD - ESPECIALLY ACROSS INTERIOR CT. THESE WILL BE NEAR RECORD VALUES AT SOME LOCATIONS. REFER TO THE CLIMATE SECTION OF THE AFD FOR DETAILS. && .LONG TERM /SATURDAY THROUGH THURSDAY/... A PROGRESSIVE...YET AMPLIFIED FLOW WILL CONTINUE THROUGH NEXT WEEK WITH ANOTHER FULL LATITUDE TROF MOVING THROUGH THE EAST EARLY NEXT WEEK. WITH NO REAL BLOCK...A NEUTRAL NAO AND PNA...COLD AIR COMES IN WITH A FURY EARLY NEXT WEEK...BUT ALSO QUICKLY LIFTS OUT IN THE MID WEEK PERIOD. MODELS DIFFER IN THE TIMING OF THE COLD FRONT ON MONDAY...WITH THE NAM WRF ON THE FASTER END OF THE SUITE...WITH THE GFS TAKING THE MIDDLE ROAD APPROACH...AND THE ECMWF LAGGING JUST BEHIND. GEFS AND SREF LEANING TOWARD THE FASTER SOLUTIONS. PREFERENCE RIGHT NOW WAS TO NOT BREAK MUCH FROM CONTINUITY WITH THE DIFFERENCES IN THE MODELS...PREFERRING A FRONTAL PASSAGE CLOSE TO DAYBREAK MON. WARM ADVECTION RAINS DEVELOP SUN AFT...PRIMARILY FROM NYC POINTS NORTH AND WEST...WITH MOST OF THE AREA SEEING WIDESPREAD RAIN SUN NIGHT INTO MON MORNING. THERMO PROFILES SUPPORT AN ALL RAIN EVENT AS COLD AIR LAGS SUFFICIENTLY BEHIND THE FRONT. STRONG COLD ADVECTION ENSUES FROM MON MORNING INTO TUE...WITH A PIECE OF THE POLAR VORTEX BREAKING OFF ACROSS THE OHIO VALLEY AND WORKING EAST ACROSS THE AREA ON TUE. 85H TEMPS ON TUE WILL BE AROUND -25 DEGREES F. THIS WILL RESULT IN HIGHS TUE ONLY IN THE SINGLE DIGITS INLAND AND THE LOWER TO MID TEENS ALONG THE COAST. ALSO OF NOTE IS THAT WINDS WILL CONTINUE TO BE GUSTY FROM A WESTERLY DIRECTION MONDAY THROUGH WEDNESDAY. WIND CHILLS FORECAST COULD REACH 0 TO -10 DEGREES F AT TIMES LATE MONDAY NIGHT THROUGH EARLY WEDNESDAY. AIRMASS GRADUALLY MODERATES WED INTO THU AS HIGH PRESSURE BUILDS TO THE SOUTH AND EAST. && .AVIATION /11Z FRIDAY THROUGH TUESDAY/... ***HIGH IMPACT WINTER STORM THROUGH THIS MORNING*** MODERATE TO LOCALLY HEAVY SNOW AND BLOWING/DRIFTING SNOW...WITH MOSTLY IFR CONDS AND MAXIMUM SNOWFALL RATES OF ABOUT AN INCH PER HOUR PER HOUR...SHOULD CONTINUE UNTIL ABOUT 11Z-12Z. ALTHOUGH FALLING SNOW SHOULD THEN TAPER OFF FROM 11Z-14Z FROM WEST TO EAST...BLOWING/DRIFTING SNOW WILL CONTINUE TO IMPACT THE TERMINALS WITH AT LEAST MVFR VSBYS INTO EARLY AFTERNOON. CONDS WILL IMPROVE TO VFR THEREAFTER. TOTAL SNOW ACCUMULATIONS WILL RANGE FROM 6-8 INCHES AT KSWF...TO 8-10 INCHES OVER WESTERN TERMINALS AND FROM 8-10 INCHES OVER EASTERN LONG ELSEWHERE...HIGHEST ACROSS LONG ISLAND. NORTH WINDS 15-25 KT WITH GUSTS 25-35 KT...HIGHEST AT THE NYC METRO AND LONG ISLAND TERMINALS...WILL BACK NW A LITTLE LATER THAN ORIGINALLY EXPECTED...BY ABOUT 14Z-15Z. NW WINDS 20 KT WITH GUSTS 25-30 KT WILL THEN CONTINUE FOR MUCH OF THE DAY...THEN DIMINISH TO 10 KT OR LESS AFTER SUNSET. NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP:/WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KLGA FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KEWR FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KHPN FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KISP FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. .OUTLOOK FOR 06Z SAT THROUGH TUE... .LATE TONIGHT...VFR WITH LIGHT NW WINDS. .SAT-SAT NIGHT...VFR. SW WINDS LESS THAN 10 KT. .SUNDAY...MVFR CONDS POSSIBLE IN THE AFTERNOON...WITH RAIN/SNOW ACROSS THE INTERIOR AND RAIN AT THE NYC METRO/LONG ISLAND/COASTAL CT TERMINALS. .SUNDAY NIGHT-MON MORNING...IFR CONDS LIKELY IN RAIN. S WINDS G20-30KT LATE SUNDAY NIGHT/MON MORNING. .MON AFTERNOON-TUE...CONDS IMPROVING TO VFR. W WINDS G20-30 KT. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. FORECAST APPEARS ON TRACK. THE HIGHEST WINDS WITH THIS STORM WILL OCCUR EARLY THIS MORNING AS THE STORM CENTER DEEPENS WHILE PASSING SE OF THE 40N/70W BENCHMARK. GALES ARE STILL EXPECTED ON ALL WATERS AT LEAST THROUGH THE MORNING HOURS. IT IS POSSIBLE THAT THE WESTERN WATERS FALL BELOW GALE WARNING CRITERIA BY AROUND NOON TODAY AND THERE IS A CHANCE THAT ALL WATERS SUBSIDE BELOW GALES BY LATE AFTERNOON. WITH NOT ENOUGH CONFIDENCE TO TRIM BACK THE GALE WARNING...WILL KEEP THE GALE WARNING AS IS...LASTING THROUGH THIS AFTERNOON. FOR THIS EVENING...SCA CONDITIONS ON ALL WATERS TO START...BUT QUICKLY SUBSIDING. ONLY THE OCEAN WATERS WILL PROBABLY STILL HAVE SCA CONDITIONS BY MIDNIGHT TONIGHT AND ONLY BECAUSE OF SEAS. SUB-SCA CONDITIONS COULD BE POSSIBLE BY SUNRISE ON SATURDAY ON THE OCEAN...IF NOT...SEAS SHOULD SUBSIDE BELOW 5 FT BY MID-MORNING. SUB SCA SAT MORNING INCREASES TO SCA SOUTHEAST OF LI LATE SAT THROUGH SUN MORNING. THIS WILL BE MAINLY ACROSS THE EASTERN OCEAN ZONES. A BRIEF RETURN TO BELOW SCA CONDITIONS WILL BE FOLLOWED BY ANOTHER ROUND OF SCA SUNDAY NIGHT INTO NEXT WEEK AS A STRONG COLD FRONT IMPACTS THE AREA. A PROLONGED PERIOD OF WESTERLY WINDS MON INTO WED WILL PRODUCE ROUGH SEAS AND NEAR GALE FORCE GUSTS ON THE OCEAN WATERS. && .HYDROLOGY... AN ADDITIONAL 1/10 TO 4/10 OF AN INCH OF LIQUID EQUIVALENT WILL FALL MAINLY THIS MORNING...ALL AS SNOW. ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A MODEL CONSENSUS ARE AROUND 0.5 TO 1 INCH. && .TIDES/COASTAL FLOODING... ALTHOUGH WINDS WILL BE OFFSHORE FOR SEVERAL HOURS BEFORE THE HIGH TIDE CYCLE OCCURS THE MORNING TO EARLY AFTERNOON...IT APPEARS THAT TIDAL PILING WILL BE MAIN FACTOR FOR COASTAL FLOODING WITH THIS CYCLE. ANOTHER FACTOR IS THAT THIS WILL BE THE HIGHER OF THE TWO DAILY ASTRONOMICAL TIDE CYCLES. THE STEVENS INSTITUTE GUIDANCE HAS BEEN THE BETTER PERFORMER WITH THIS STORM SO FAR AND WHEN FACTORING IN AN EXTRA RESIDUAL (NOTING RECENT OBSERVATIONS) ON TOP OF ITS SURGE GUIDANCE...IT APPEARS LIKELY THAT THERE WILL BE WIDESPREAD MINOR COASTAL FLOODING WITH THIS UPCOMING TIDE CYCLE. HOWEVER...WITH HIGH WAVES AND A SE SWELL FOR A GOOD PORTION LEADING UP TO THE MID-MORNING HOURS...THE SOUTH-SHORE BACK BAYS OF NASSAU AND QUEENS WILL PROBABLY EXPERIENCE MODERATE COASTAL FLOODING. IT IS ALSO NOT OUT OF THE QUESTION FOR LOCALLY MODERATE COASTAL FLOODING FOR THE PARTS OF THE LOWER HARBOR...BUT THINKING IS THAT ANY MODERATE FLOODING WOULD BE JUST ISOLATED. WITH THIS SAID...WILL BE GOING WITH A COASTAL FLOOD ADVISORY FOR ALL COASTAL ZONES WITH THE EXCEPTION OF SOUTHERN NASSAU AND QUEENS WHERE A COASTAL FLOOD WARNING WILL BE WARRANTED. ALSO...NO HEADLINES FOR SOUTHERN NEW LONDON COUNTY AS THEY LIKELY FALL SHORT OF MINOR THRESHOLDS. THERE IS A REASONABLE CHANCE HOWEVER SOUTHERN NASSAU AND QUEENS DON/T EXPERIENCE WIDESPREAD MODERATE FLOODING...AND INSTEAD JUST HAVE MINOR FLOODING. IT IS ALSO POSSIBLE THAT PARTS OF SOUTHERN MIDDLESEX COUNTY DO NOT EVEN REACH MINOR COASTAL FLOODING. NOT EXPECTING ANY COASTAL FLOODING ISSUES WITH TONIGHT/S HIGH TIDE CYCLE AS IT WILL BE THE LOWER OF THE TWO TIDE CYCLES AND TIDAL PILING WOULD NO LONGER BE A FACTOR. && .CLIMATE... CLIMATE RECORDS FOR JANUARY 3: LOCATION RECORD LOW HIGH FORECAST VALUE BRIDGEPORT...CT 16 1981 17 ISLIP...NY 20 2008 13 LAGUARDIA...NY 17 1981 18 JFK AIRPORT...NY 22 2008/1981 17 NYC-CENTRAL PARK...NY 12 1918 16 NEWARK...NJ 19 1981 17 LOCATION RECORD LOW FORECAST VALUE BRIDGEPORT...CT 9 2008 9 ISLIP...NY 7 2001 10 LAGUARDIA...NY 12 1981 7 JFK AIRPORT...NY 14 2008 11 NYC-CENTRAL PARK...NY -4 1879 8 NEWARK...NJ 10 1981 8 CLIMATE RECORDS FOR JANUARY 4: LOCATION RECORD LOW FORECAST VALUE BRIDGEPORT...CT -1 1981 1 ISLIP...NY 10 2008 2 LAGUARDIA...NY 4 1981 2 JFK AIRPORT...NY 8 1981 3 NYC-CENTRAL PARK...NY -3 1981 2 NEWARK...NJ 1 1981 1 && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM EST THIS AFTERNOON FOR CTZ009>011. WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR CTZ005>012. NY...COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM EST THIS AFTERNOON FOR NYZ071-073-078-079-176-177. BLIZZARD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ078>081- 177-179. WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ067>075-176-178. COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR NYZ072- 074-075. COASTAL FLOOD WARNING UNTIL 11 AM EST THIS MORNING FOR NYZ178- 179. COASTAL FLOOD ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NYZ080-081. NJ...WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NJZ002- 004-006-103>108. COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR NJZ006- 106-108. MARINE...GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ330-335-338- 340-345-350-353-355. && $$ SYNOPSIS...MALOIT/DW NEAR TERM...MALOIT/PW SHORT TERM...MALOIT/PW LONG TERM...DW AVIATION...GOODMAN MARINE...JC/MALOIT/DW HYDROLOGY...MALOIT/DW TIDES/COASTAL FLOODING... CLIMATE... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
422 AM EST FRI JAN 3 2014 .SYNOPSIS... A POTENT STORM SYSTEM TRACKS INTO THE CANADIAN MARITIMES AS ARCTIC HIGH PRESSURE BUILDS IN THROUGH TONIGHT. HIGH PRESSURE BUILDS OFFSHORE ON SATURDAY AHEAD OF A COLD FRONT MOVING ACROSS THE UPPER MIDWEST AND GREAT LAKES. A WAVE OF LOW PRESSURE THEN FORMS ALONG THE FRONT OVER THE TENNESSEE VALLEY ON SUNDAY...TRACKING NORTHEAST INTO EASTERN CANADA ON MONDAY. AS IT DOES SO...IT WILL SEND AN ARCTIC COLD FRONT THROUGH THE REGION IN THE MORNING. HIGH PRESSURE BUILDS TO THE SOUTH AND WEST OF THE REGION THROUGH MID NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 992 HPA LOW WAS LOCATED ABOUT 225 SE OF KMTP AT 8Z. LOW LEVEL FRONTOGENETIC FORCING TO THE NW OF THE LOW PRODUCING SNOW BANDS ACROSS THE NYC METRO AND LONG ISLAND EARLY THIS MORNING. BASED ON BANDING A BIT MORE WIDESPREAD THAN EXPECTED AND TEMPERATURES A TAD COLDER THAN FORECAST PROMOTING SLIGHTLY HIGHER SNOW TO LIQUID RATIOS...HAVE UPPED SNOW FALL TOTALS TO 8-12 INCHES ACROSS LONG ISLAND AND 6-10 ACROSS THE NEW YORK CITY/NE NJ/S WESTCHESTER. SNOW SHOULD TAPER OFF FROM W TO E BY AROUND MID MORNING BASED ON TIMING OF BACK EDGE OF SNOW ON RADAR. SOME INDICATION THAT COULD HAVE A LINGERING DEFORMATION BAND OVER EASTERN LONG ISLAND INTO EARLY AFTERNOON - BUT FOR NOW DO NOT THINK WILL ADD MUCH TO ACCUMULATION. WILL NEED TO MONITOR THIS FEATURE THOUGH - AS SOMETIMES THEY ARE GOOD FOR AN EXTRA INCH OR TWO OF SNOWFALL. EVEN AS SNOW SHUTS DOWN - STRONG N-NE WINDS GUSTING TO 30-45 MPH WILL CAUSING BLOWING OF THE DRY POWDERY SNOW AND VERY LOW WIND CHILLS - WITH VALUES 15 TO 20 BELOW ZERO ACROSS NORTHERN INTERIOR ZONES AND 5 TO 10 BELOW ELSEWHERE INTO THE EARLY AFTERNOON HOURS. AS A RESULT HAVE LEFT THE WINTER WEATHER HEADLINES AS IS. WINDS DIMINISH THIS AFTERNOON - WITH WIND CHILLS INCREASING TO FROM -10 TO AROUND 0. FOR HIGHS TODAY TOOK A BLEND OF MIXING DOWN FROM 925 HPA PER BUFKIT SOUNDINGS WITH NAM AND RUC 2-METER TEMPERATURES AND A BLEND OF MAV/MET GUIDANCE. EXPECT VALUES DURING THE TEENS TODAY - WITH MOST HIGHS FOR THE DAY REACHED JUST AFTER MIDNIGHT - AND THE WARMEST TEMPERATURES DURING THE DAYLIGHT HOURS LIKELY DURING THE MORNING HOURS. RECORD LOW TEMPERATURES AND RECORD LOW MAXIMUM TEMPERATURES ARE LIKELY TODAY AT SOME CLIMATE SITES. SEE THE CLIMATE SECTION OF THE AFD FOR DETAILS. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/... MAINLY CLEAR SKY CONDITIONS IN THE WAKE OF THE DEPARTING LOW COUPLED WITH SNOW COVER AND DIMINISHING WINDS WILL ALLOW FOR LOWS TO PLUMMET TONIGHT. LOWS WILL BE MAINLY FROM 5 ABOVE TO AROUND 10 BELOW - COLDEST ACROSS THE NORTHERN TIER. THIS AROUND 20-25 DEGREES BELOW NORMAL - AND CONSISTENT WITH TAKING THE LOWEST OF MAV/MET/NAM 2-METER TEMPERATURES AND BLENDING 2 PARTS OF THIS AND 1 PART OF A BLEND OF MAV/MET/NAM 2-METER TEMPERATURES. THIS INSURES THAT THE FORECAST LOWS ARE COLDER THAN A BLEND OF GUIDANCE - HOWEVER NAM 2-METER TEMPERATURES ACROSS THE INTERIOR SEEMED EXCESSIVELY COLD - ESPECIALLY ACROSS INTERIOR CT. THESE WILL BE NEAR RECORD VALUES AT SOME LOCATIONS. REFER TO THE CLIMATE SECTION OF THE AFD FOR DETAILS. && .LONG TERM /SATURDAY THROUGH THURSDAY/... A PROGRESSIVE...YET AMPLIFIED FLOW WILL CONTINUE THROUGH NEXT WEEK WITH ANOTHER FULL LATITUDE TROF MOVING THROUGH THE EAST EARLY NEXT WEEK. WITH NO REAL BLOCK...A NEUTRAL NAO AND PNA...COLD AIR COMES IN WITH A FURY EARLY NEXT WEEK...BUT ALSO QUICKLY LIFTS OUT IN THE MID WEEK PERIOD. MODELS DIFFER IN THE TIMING OF THE COLD FRONT ON MONDAY...WITH THE NAM WRF ON THE FASTER END OF THE SUITE...WITH THE GFS TAKING THE MIDDLE ROAD APPROACH...AND THE ECMWF LAGGING JUST BEHIND. GEFS AND SREF LEANING TOWARD THE FASTER SOLUTIONS. PREFERENCE RIGHT NOW WAS TO NOT BREAK MUCH FROM CONTINUITY WITH THE DIFFERENCES IN THE MODELS...PREFERRING A FRONTAL PASSAGE CLOSE TO DAYBREAK MON. WARM ADVECTION RAINS DEVELOP SUN AFT...PRIMARILY FROM NYC POINTS NORTH AND WEST...WITH MOST OF THE AREA SEEING WIDESPREAD RAIN SUN NIGHT INTO MON MORNING. THERMO PROFILES SUPPORT AN ALL RAIN EVENT AS COLD AIR LAGS SUFFICIENTLY BEHIND THE FRONT. STRONG COLD ADVECTION ENSUES FROM MON MORNING INTO TUE...WITH A PIECE OF THE POLAR VORTEX BREAKING OFF ACROSS THE OHIO VALLEY AND WORKING EAST ACROSS THE AREA ON TUE. 85H TEMPS ON TUE WILL BE AROUND -25 DEGREES F. THIS WILL RESULT IN HIGHS TUE ONLY IN THE SINGLE DIGITS INLAND AND THE LOWER TO MID TEENS ALONG THE COAST. ALSO OF NOTE IS THAT WINDS WILL CONTINUE TO BE GUSTY FROM A WESTERLY DIRECTION MONDAY THROUGH WEDNESDAY. WIND CHILLS FORECAST COULD REACH 0 TO -10 DEGREES F AT TIMES LATE MONDAY NIGHT THROUGH EARLY WEDNESDAY. AIRMASS GRADUALLY MODERATES WED INTO THU AS HIGH PRESSURE BUILDS TO THE SOUTH AND EAST. && .AVIATION /09Z FRIDAY THROUGH TUESDAY/... ***HIGH IMPACT WINTER STORM THROUGH THIS MORNING*** MODERATE TO LOCALLY HEAVY SNOW AND BLOWING/DRIFTING SNOW...WITH MOSTLY IFR CONDS AND MAXIMUM SNOWFALL RATES OF ABOUT AN INCH PER HOUR PER HOUR...SHOULD CONTINUE UNTIL ABOUT 11Z-12Z. ALTHOUGH FALLING SNOW SHOULD THEN TAPER OFF FROM 11Z-14Z FROM WEST TO EAST...BLOWING/DRIFTING SNOW WILL CONTINUE TO IMPACT THE TERMINALS WITH AT LEAST MVFR VSBYS INTO EARLY AFTERNOON. CONDS WILL IMPROVE TO VFR THEREAFTER. TOTAL SNOW ACCUMULATIONS WILL RANGE FROM 6-8 INCHES AT KSWF...TO 8-10 INCHES OVER WESTERN TERMINALS AND FROM 8-10 INCHES OVER EASTERN LONG ELSEWHERE...HIGHEST ACROSS LONG ISLAND. NORTH WINDS 15-25 KT WITH GUSTS 25-35 KT...HIGHEST AT THE NYC METRO AND LONG ISLAND TERMINALS...WILL BACK NW A LITTLE LATER THAN ORIGINALLY EXPECTED...BY ABOUT 14Z-15Z. NW WINDS 20 KT WITH GUSTS 25-30 KT WILL THEN CONTINUE FOR MUCH OF THE DAY...THEN DIMINISH TO 10 KT OR LESS AFTER SUNSET. ...NY METRO ENHANCED AVIATION WEATHER SUPPORT... DETAILED INFORMATION...INCLUDING HOURLY TAF WIND COMPONENT FCSTS CAN BE FOUND AT: HTTP://WWW.ERH.NOAA.GOV/ZNY/N90 (LOWER CASE) KJFK FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KLGA FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KEWR FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. THE AFTERNOON KEWR HAZE POTENTIAL FORECAST IS GREEN...WHICH IMPLIES SLANT RANGE VISIBILITY 7SM OR GREATER OUTSIDE OF CLOUD. KTEB FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KHPN FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. KISP FCSTER COMMENTS: AMD LIKELY AFTER 12Z TO FINE TUNE WINDS AND FLIGHT CAT AS SNOW ENDS BUT AS BLOWING SNOW CONTINUES. .OUTLOOK FOR 06Z SAT THROUGH TUE... .LATE TONIGHT...VFR WITH LIGHT NW WINDS. .SAT-SAT NIGHT...VFR. SW WINDS LESS THAN 10 KT. .SUNDAY...MVFR CONDS POSSIBLE IN THE AFTERNOON...WITH RAIN/SNOW ACROSS THE INTERIOR AND RAIN AT THE NYC METRO/LONG ISLAND/COASTAL CT TERMINALS. .SUNDAY NIGHT-MON MORNING...IFR CONDS LIKELY IN RAIN. S WINDS G20-30KT LATE SUNDAY NIGHT/MON MORNING. .MON AFTERNOON-TUE...CONDS IMPROVING TO VFR. W WINDS G20-30 KT. && .MARINE... THE HIGHEST WINDS WITH THIS STORM WILL OCCUR EARLY THIS MORNING AS THE STORM CENTER DEEPENS WHILE PASSING SE OF THE 40N/70W BENCHMARK. GALES ARE STILL EXPECTED ON ALL WATERS AT LEAST THROUGH THE MORNING HOURS. IT IS POSSIBLE THAT THE WESTERN WATERS FALL BELOW GALE WARNING CRITERIA BY AROUND NOON TODAY AND THERE IS A CHANCE THAT ALL WATERS SUBSIDE BELOW GALES BY LATE AFTERNOON. WITH NOT ENOUGH CONFIDENCE TO TRIM BACK THE GALE WARNING...WILL KEEP THE GALE WARNING AS IS...LASTING THROUGH THIS AFTERNOON. FOR THIS EVENING...SCA CONDITIONS ON ALL WATERS TO START...BUT QUICKLY SUBSIDING. ONLY THE OCEAN WATERS WILL PROBABLY STILL HAVE SCA CONDITIONS BY MIDNIGHT TONIGHT AND ONLY BECAUSE OF SEAS. SUB-SCA CONDITIONS COULD BE POSSIBLE BY SUNRISE ON SATURDAY ON THE OCEAN...IF NOT...SEAS SHOULD SUBSIDE BELOW 5 FT BY MID-MORNING. SUB SCA SAT MORNING INCREASES TO SCA SOUTHEAST OF LI LATE SAT THROUGH SUN MORNING. THIS WILL BE MAINLY ACROSS THE EASTERN OCEAN ZONES. A BRIEF RETURN TO BELOW SCA CONDITIONS WILL BE FOLLOWED BY ANOTHER ROUND OF SCA SUNDAY NIGHT INTO NEXT WEEK AS A STRONG COLD FRONT IMPACTS THE AREA. A PROLONGED PERIOD OF WESTERLY WINDS MON INTO WED WILL PRODUCE ROUGH SEAS AND NEAR GALE FORCE GUSTS ON THE OCEAN WATERS. && .HYDROLOGY... AN ADDITIONAL 1/10 TO 4/10 OF AN INCH OF LIQUID EQUIVALENT WILL FALL MAINLY THIS MORNING...ALL AS SNOW. ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME MINOR FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A MODEL CONSENSUS ARE AROUND 0.5 TO 1 INCH. && .TIDES/COASTAL FLOODING... ALTHOUGH WINDS WILL BE OFFSHORE FOR SEVERAL HOURS BEFORE THE HIGH TIDE CYCLE OCCURS THE MORNING TO EARLY AFTERNOON...IT APPEARS THAT TIDAL PILING WILL BE MAIN FACTOR FOR COASTAL FLOODING WITH THIS CYCLE. ANOTHER FACTOR IS THAT THIS WILL BE THE HIGHER OF THE TWO DAILY ASTRONOMICAL TIDE CYCLES. THE STEVENS INSTITUTE GUIDANCE HAS BEEN THE BETTER PERFORMER WITH THIS STORM SO FAR AND WHEN FACTORING IN AN EXTRA RESIDUAL (NOTING RECENT OBSERVATIONS) ON TOP OF ITS SURGE GUIDANCE...IT APPEARS LIKELY THAT THERE WILL BE WIDESPREAD MINOR COASTAL FLOODING WITH THIS UPCOMING TIDE CYCLE. HOWEVER...WITH HIGH WAVES AND A SE SWELL FOR A GOOD PORTION LEADING UP TO THE MID-MORNING HOURS...THE SOUTH-SHORE BACK BAYS OF NASSAU AND QUEENS WILL PROBABLY EXPERIENCE MODERATE COASTAL FLOODING. IT IS ALSO NOT OUT OF THE QUESTION FOR LOCALLY MODERATE COASTAL FLOODING FOR THE PARTS OF THE LOWER HARBOR...BUT THINKING IS THAT ANY MODERATE FLOODING WOULD BE JUST ISOLATED. WITH THIS SAID...WILL BE GOING WITH A COASTAL FLOOD ADVISORY FOR ALL COASTAL ZONES WITH THE EXCEPTION OF SOUTHERN NASSAU AND QUEENS WHERE A COASTAL FLOOD WARNING WILL BE WARRANTED. ALSO...NO HEADLINES FOR SOUTHERN NEW LONDON COUNTY AS THEY LIKELY FALL SHORT OF MINOR THRESHOLDS. THERE IS A REASONABLE CHANCE HOWEVER SOUTHERN NASSAU AND QUEENS DON/T EXPERIENCE WIDESPREAD MODERATE FLOODING...AND INSTEAD JUST HAVE MINOR FLOODING. IT IS ALSO POSSIBLE THAT PARTS OF SOUTHERN MIDDLESEX COUNTY DO NOT EVEN REACH MINOR COASTAL FLOODING. NOT EXPECTING ANY COASTAL FLOODING ISSUES WITH TONIGHT/S HIGH TIDE CYCLE AS IT WILL BE THE LOWER OF THE TWO TIDE CYCLES AND TIDAL PILING WOULD NO LONGER BE A FACTOR. && .CLIMATE... CLIMATE RECORDS FOR JANUARY 3: LOCATION RECORD LOW HIGH FORECAST VALUE BRIDGEPORT...CT 16 1981 18 ISLIP...NY 20 2008 17 LAGUARDIA...NY 17 1981 18 JFK AIRPORT...NY 22 2008/1981 18 NYC-CENTRAL PARK...NY 12 1918 17 NEWARK...NJ 19 1981 18 LOCATION RECORD LOW FORECAST VALUE BRIDGEPORT...CT 9 2008 9 ISLIP...NY 7 2001 10 LAGUARDIA...NY 12 1981 7 JFK AIRPORT...NY 14 2008 11 NYC-CENTRAL PARK...NY -4 1879 8 NEWARK...NJ 10 1981 8 CLIMATE RECORDS FOR JANUARY 4: LOCATION RECORD LOW FORECAST VALUE BRIDGEPORT...CT -1 1981 1 ISLIP...NY 10 2008 2 LAGUARDIA...NY 4 1981 2 JFK AIRPORT...NY 8 1981 3 NYC-CENTRAL PARK...NY -3 1981 2 NEWARK...NJ 1 1981 1 && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM EST THIS AFTERNOON FOR CTZ009>011. WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR CTZ005>012. NY...COASTAL FLOOD ADVISORY FROM 10 AM THIS MORNING TO 2 PM EST THIS AFTERNOON FOR NYZ071-073-078-079-176-177. BLIZZARD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ078>081- 177-179. WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ067>075-176-178. COASTAL FLOOD ADVISORY FROM 7 AM TO 11 AM EST THIS MORNING FOR NYZ072-074-075. COASTAL FLOOD WARNING FROM 7 AM TO 11 AM EST THIS MORNING FOR NYZ178-179. COASTAL FLOOD ADVISORY FROM 9 AM THIS MORNING TO 1 PM EST THIS AFTERNOON FOR NYZ080-081. NJ...WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NJZ002- 004-006-103>108. COASTAL FLOOD ADVISORY FROM 7 AM TO 11 AM EST THIS MORNING FOR NJZ006-106-108. MARINE...GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ330-335-338- 340-345-350-353-355. && $$ SYNOPSIS...MALOIT/DW NEAR TERM...MALOIT/PW SHORT TERM...MALOIT/PW LONG TERM...DW AVIATION...GOODMAN MARINE...JC/DW HYDROLOGY...MALOIT/DW TIDES/COASTAL FLOODING... CLIMATE...MALOIT/LN EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
157 AM EST FRI JAN 3 2014 .SYNOPSIS... DEEPENING LOW PRESSURE PASSES TO THE SOUTH TONIGHT...THEN DEPARTS TO THE EAST FRIDAY. HIGH PRESSURE BUILDS FRIDAY NIGHT. HIGH PRESSURE WILL MOVE EAST AND OFFSHORE THIS WEEKEND WITH ANOTHER LOW DEVELOPING ALONG THE APPALACHIANS SUNDAY. THIS WILL DEEPEN TO THE WEST OF THE REGION WITH A COLD FRONT MOVING ACROSS MONDAY. ANOTHER ARCTIC AIR MASS BUILDS IN BEHIND IT AS WESTERN CANADA HIGH PRESSURE BUILDS TO THE SOUTH AND WEST OF THE REGION THROUGH MID NEXT WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... TEMPERATURES ARE FALLING OFF MORE RAPIDLY THAN FORECAST - HAVE ADJUSTED DOWNWARD BASED ON HRRR 2-M TEMPERATURES WHICH SEEM TO AVE BEST HANDLE ON CURRENT TRENDS. AS A RESULT - COULD END UP WITH SLIGHTLY HIGHER SNOW TO LIQUID RATIOS - SO ADDED LOCALLY HIGHER AMOUNTS POSSIBLE TO THE WSW TEXT. SPS OUT FOR SNOW BAND IMPACTING S NASSAU AND SUFFOLK - WITH RATES 1-2 INCH/HR. WILL MONITOR AND UPDATE AMOUNTS IF NEEDED. AT 4Z A 996 HPA LOW WAS LOCATED ABOUT 210 MILES S OF KMTP LIFTING NNE PER LATEST PRESSURE FALLS...WITH RAPID DEEPENING EXPECTED TO CONTINUE. WITH THE STEEP PRESSURE FALLS DUE EXPECT WINDS TO CONTINUE TO INCREASE OVER THE AREA. DEPENDING ON HOW WINDS AND VISIBILITIES TREND - THERE IS A CHANCE FOR A SHORT FUSED EXPANSION OF THE BLIZZARD WARNING - WITH MOST LIKELY CANDIDATES BEING SE CT AND POSSIBLY NYC. EXPECT HEAVIEST SNOWFALL ACROSS THE AREA GENERALLY THROUGH 9Z THEN A TAPERING OFF FROM W TO E. MODEL OUTPUT FOR TONIGHT REMAINS FAIRLY CLOSE...WITH GFS AND ECMWF A BIT WETTER THAN NAM/WRF. SREF ENSEMBLE WOULD SUGGEST A QPF BLEND IS PERHAPS THE WAY TO GO AT THIS TIME. QPF OF AROUND 1/2 INCH TO 3/4 OF AN INCH IS EXPECTED. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/... VERY COLD AIR THIS TIME FRAME. MORNING SNOW ENDS FROM WEST TO EAST AS THE UPPER TROUGH PIVOTS ACROSS THE NORTHEAST AND THE DEEPENING COASTAL LOW DEPARTS. SNOW ACCUMULATIONS 5 TO 10 INCHES...WITH PERHAPS SOME HIGHER AMOUNTS OVER LI PER LOW TRACK/HEAVIEST SNOW CLIMATOLOGY. WINDY CONDITIONS WILL RESULT IN BLOWING SNOW THROUGH THE MORNING AND INTO THE AFTERNOON. SKIES CLEAR DURING THE AFTERNOON...AGAIN FROM WEST TO EAST. TEMPS RISE LITTLE DURING THE DAY...AND IN FACT REMAIN NEARLY STEADY BEFORE DROPPING LATER IN THE DAY. MAX TEMPS IN THE TEENS EXPECTED. FOR FRIDAY NIGHT...A RIDGE OF HIGH PRESSURE BUILDS IN. AS WINDS LIGHTEN AND SKIES REMAIN CLEAR...TEMPS WILL PLUMMET INTO THE SINGLE DIGITS AND BELOW ZERO ACROSS THE REGION. WENT CLOSER TO COLDER MAV DATA...WHICH MAY NOT EVEN BE COLD ENOUGH AS MOS TRENDS TOWARD CLIMATOLOGY AND DOES NOT USUALLY HANDLE IMPACTS OF A FRESH SNOW PACK WELL. HOWEVER...SOME WAA MID AND HIGH CLOUDS APPROACH LATE AT NIGHT...WHICH COULD HAVE A MINOR IMPACT ON TEMPS. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... THE JET STREAM LIFTS GRADUALLY NORTH OF THE REGION THIS WEEKEND BUT WILL DIVE BACK SOUTH OF THE REGION FOR NEXT WEEK. A RIDGING TREND IN THE MID LEVELS MUCH OF THE WEEKEND WITH DECREASING HEIGHTS SUNDAY AFTERNOON INTO NEXT WEEK WITH A MUCH COLDER AIR MASS APPROACHING. AT THE SURFACE...THE ARCTIC HIGH PRESSURE WILL BE CENTERED ACROSS THE REGION SATURDAY MORNING AND WILL PUSH OFFSHORE THROUGH THE DAY. THIS WILL CONTINUE TO MOVE EAST THROUGH THE WEEKEND...WITH A CONTINUANCE OF RETURN SOUTHERLY FLOW. THE RESULT WILL BE A MODERATION OF THE AIR MASS...ALTHOUGH WITH LIMITED MIXING HEIGHTS SATURDAY...ONLY TO BETWEEN 1000 AND 950 MB. HIGHS ARE FORECAST TO STILL BE ABOUT 10 DEGREES BELOW NORMAL. THE MODERATION WILL BE MORE REMARKABLE AT NIGHT...ESPECIALLY ALONG THE COAST WITH THE INCREASINGLY ONSHORE FLOW AS HIGH PRESSURE CONTINUE TO MOVES OFFSHORE. LOWS SATURDAY NIGHT ARE FORECAST TO BE CLOSER TO NORMAL BUT STILL LIKELY BELOW NORMAL ACROSS THE INTERIOR WITH LIGHTER WINDS THERE. A REMARKABLE REBOUND IN TEMPERATURES FOR SUNDAY WITH THE CONTINUED RETURN SOUTHERLY FLOW. HOWEVER...TEMPERATURES FREEZING OR BELOW IN THE MORNING WITH NEXT WAVE OF LOW PRESSURE TO OUR WEST APPROACHING WILL LEAD TO WARMER TEMPERATURES ALOFT. THIS WILL PRESENT A CHANCE FOR A WINTRY MIX TO START...CHANGING TO RAIN FROM SOUTHEAST TO NORTHWEST LATER IN THE DAY AS WARMER AIR RIDES INTO THE AREA. MAINLY RAIN AT NIGHT AHEAD OF THE COLD FRONT AND ANOMALOUSLY WARM AIR ADVECTING OVER THE AREA. ALONG WITH THIS WILL ALSO BE ADVECTION FOG...PATCHY IN NATURE DURING THE AREA BUT LIKELY GROWING IN AREA AT NIGHT...ESPECIALLY IN ANY LULLS IN RAIN ACTIVITY. TEMPERATURES WILL BE ON A NON-DIURNAL TREND...RISING SLOWLY SUNDAY EVENING. A PERIOD OF MODERATE RAIN IS FORECAST SUNDAY NIGHT INTO EARLY MONDAY. THIS RAIN COULD BE POTENTIALLY HEAVY AT TIMES WITH PRECIPITABLE WATER VALUES OF SLIGHTLY OVER 1 INCH...WHICH IS CLOSE TO 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THE MONTH OF JANUARY. THE RAIN WILL THEN TAPER OFF FROM WEST TO EAST DURING THE DAY MONDAY WITH SHOWER ACTIVITY BEHIND THE FRONT. SHARP COLD AIR ADVECTION ON A STRENGTHENING NORTHWEST FLOW WILL ALLOW FOR SOME SNOW SHOWERS AS WE GO THROUGH THE DAY. MAX TEMPERATURES FOR MONDAY WILL LIKELY BY SET IN THE MORNING WITH LOWERING TEMPERATURES FOR THE REMAINDER OF THE DAY. ANOTHER VERY COLD AIR MASS BUILDS IN THROUGH MID NEXT WEEK WITH MUCH BELOW NORMAL TEMPS. HIGH PRESSURE FROM WESTERN CANADA WILL BE BUILDING TO THE SOUTH AND WEST OF THE REGION. ANOTHER ROUND OF SNOW SHOWERS WILL BE POSSIBLE ACROSS EASTERN LONG ISLAND AND SOUTHEAST CT TUESDAY INTO TUESDAY EVENING AS WELL AS NEXT THURSDAY AS PERIODIC SHORTWAVES ALOFT MOVE ACROSS. TOWARDS THE END OF NEXT WEEK THE DEEP ANOMALOUS TROUGH PATTERN CHANGES TO MORE OF A QUASI-ZONAL FLOW. ALSO OF NOTE IS THAT WINDS WILL CONTINUE TO BE GUSTY FROM A WESTERLY DIRECTION MONDAY THROUGH WEDNESDAY. WIND CHILLS FORECAST COULD REACH 0 TO -10 DEGREES F AT TIMES LATE MONDAY NIGHT THROUGH EARLY WEDNESDAY. UNCERTAINTY IS HIGHER WITH THE FORECAST SUNDAY NIGHT THROUGH MONDAY. VAST DIFFERENCES ARE EVIDENT WITHIN THE ECMWF AND GFS SOLUTIONS. THESE DIFFERENCES ALSO ARE APPARENT WITHIN THE GFS ENSEMBLE AND MUCH OF ITS MEMBERS WITH THE LAST TWO RUNS. THE FORECAST CURRENTLY SIDES MORE WITH THE ECMWF SOLUTION WITH A SLOWER FRONTAL SPEED AND MORE WESTERN TRACK OF THE LOW SUNDAY INTO MONDAY. && .AVIATION /07Z FRIDAY THROUGH TUESDAY/... ***HIGH IMPACT WINTER STORM THROUGH THIS MORNING*** MODERATE TO LOCALLY HEAVY SNOW AND BLOWING/DRIFTING SNOW...WITH LIFR/VLIFR CONDS AND MAXIMUM SNOWFALL RATES OF UP TO AN INCH PER HOUR PER HOUR THROUGH ABOUT 11Z-12Z. ALTHOUGH FALLING SNOW WILL TAPER OFF FROM 12Z-14Z FROM WEST TO EAST...BLOWING/DRIFTING SNOW WILL CONTINUE TO IMPACT THE TERMINALS WITH AT LEAST MVFR VSBYS UNTIL MIDDAY. CONDS IMPROVE TO VFR BY EARLY AFTERNOON. TOTAL SNOW ACCUMULATIONS WILL RANGE FROM 6-8 INCHES OVER WESTERN TERMINALS AND FROM 8-10 INCHES OVER EASTERN LONG ISLAND AND SOUTHEAST CT. NORTH WINDS /350-010 MAG/ 20-25 KT WITH GUSTS 30-35 KT WILL BACK NW /320-340 MAG/ AFTER 12Z. NW WINDS 20-25 KT WITH GUSTS 25-35 KT WILL CONTINUE FOR MUCH OF THE DAY...THEN DIMINISH TO 10 KT OR LESS BY 06Z SAT. .OUTLOOK FOR 06Z SAT THROUGH TUE... .FRI NIGHT...VFR. .SAT-SAT NIGHT...VFR. SW WINDS LESS THAN 10 KT. .SUNDAY...MVFR CONDS POSSIBLE IN THE AFTERNOON...WITH RAIN/SNOW ACROSS THE INTERIOR AND RAIN AT THE NYC METRO/LONG ISLAND/COASTAL CT TERMINALS. .SUNDAY NIGHT-MON MORNING...IFR CONDS LIKELY IN RAIN. S WINDS G20-30KT LATE SUNDAY NIGHT/MON MORNING. .MON AFTERNOON-TUE...CONDS IMPROVING TO VFR. W WINDS G20-30 KT. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. BASED ON DEEPENING DID ADD OCCASIONAL GUSTS TO 50 KT FOR THE TWO EASTERN COASTAL OCEAN ZONES OVERNIGHT. WIND AND GUSTS CONTINUE TO INCREASE OVERNIGHT AS THE LOW DEEPENS AND TRACK SOUTH OF THE WATERS. VERY ROUGH CONDITIONS ARE ANTICIPATED ON THE WATERS THROUGH FRIDAY. DEEPENING LOW PRESSURE PASSES TO THE SOUTH AND EAST THIS TIME FRAME...WITH GALES EXPECTED TONIGHT INTO FRIDAY. FREEZING SPRAY REMAINS A CONCERN AS WELL. GALE CONDITIONS END LATER FRIDAY AS HIGH PRESSURE BUILDS. WINDS DIMINISH QUITE A BIT FRIDAY NIGHT AS THE RIDGE BUILDS. ROUGH SEAS TONIGHT AND FRIDAY SLOWLY SUBSIDE LATE FRIDAY AND FRIDAY NIGHT. SUB SCA SAT MORNING INCREASES TO SCA SOUTHEAST OF LI LATE SAT THROUGH SUN MORNING. THIS WILL BE MAINLY ACROSS THE EASTERN OCEAN ZONES. A BRIEF RETURN TO BELOW SCA CONDITIONS WILL BE FOLLOWED BY ANOTHER ROUND OF SCA SUNDAY NIGHT INTO NEXT WEEK. && .HYDROLOGY... BETWEEN 1/2 TO 3/4 OF AN INCH OF LIQUID EQUIVALENT IS EXPECTED THROUGH FRIDAY...ALL FALLING AS SNOW. ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A MODEL CONSENSUS ARE AROUND 0.5 TO 1 INCH. && .TIDES/COASTAL FLOODING... THE HEIGHT OF THE STORM COMES THRU OVERNIGHT...AS A RESULT PEAK WINDS DO NOT LINE UP WITH THE HIGH TIDE CYCLES IN THE CITY AND ALONG THE GREAT S BAY. ADVISORY WILL EXPIRE AT MIDNIGHT FOR GREAT SOUTH BAY - WITH MINOR FLOODING MEASURED AT AREA GAGES THERE. ACROSS THE SOUND...HIGH TIDE IS AROUND MIDNIGHT...SO THIS LINES UP BETTER WITH THE GALE FORCE WINDS. SEAS HAVE ALREADY BEEN REPORTED AT 4 FT ON THE SOUND...SO EXPECT WAVES COULD REACH AS HIGH AS 3-6 FT ON THE N FACING SOUND COASTS. AS A RESULT...THIS SHOULD COMBINE WITH THE SURGE TO PRODUCE MODERATE FLOODING. A WARNING HAS THEREFORE BEEN ISSUED FROM THE BRONX AROUND TO CNTRL SUFFOLK. DUE TO OFFSHORE COMPONENT WINDS...EXPECTING THE IMPACTS TO BE LESSER FROM WESTCHESTER TO CT...SO AN ADVY ISSUED FOR THOSE SPOTS. AN INCREASE OF A HALF FT IN SURGE ABV THE HIGHEST GUIDANCE WILL BE REQUIRED FOR THESE AREAS TO REACH MODERATE. AN ADVY HAS ALSO BEEN POSTED FOR SERN LI. THIS IS PRIMARILY FOR THE N FACING PORTIONS OF THE S FORK AND SUSCEPTIBLE AREAS ALONG THE ATLANTIC WHERE WAVE ACTION WILL SUPPLEMENT THE SURGE. THERE IS CONSIDERABLE SPREAD WITH THE GUIDANCE FOR THE FRIDAY MRNG/AFTN HIGH TIDE CYCLE...PARTICULARLY ACROSS THE WRN SOUND WHERE THE ETSS IS TRYING TO HOLD ONTO A SIGNIFICANT AMOUNT OF WATER. BECAUSE THIS SOLN IS AN OUTLIER...MINOR OR BLW IS THE MOST LIKELY OUTCOME FOR ALL AREAS ATTM. MINOR BEACH EROSION CAN BE EXPECTED ALONG PORTIONS OF THE SOUND AND WRN OCEAN...WITH MODERATE EROSION ALONG THE CNTRL AND ERN OCEANFRONT. && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR CTZ005>012. COASTAL FLOOD ADVISORY UNTIL 2 AM EST EARLY THIS MORNING FOR CTZ009-010. NY...BLIZZARD WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ078>081- 177-179. WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NYZ067>075-176-178. COASTAL FLOOD ADVISORY UNTIL 2 AM EST EARLY THIS MORNING FOR NYZ071. COASTAL FLOOD WARNING UNTIL 2 AM EST EARLY THIS MORNING FOR NYZ073-078-176-177. NJ...WINTER STORM WARNING UNTIL 1 PM EST THIS AFTERNOON FOR NJZ002- 004-006-103>108. MARINE...GALE WARNING UNTIL 6 PM EST THIS EVENING FOR ANZ330-335-338- 340-345-350-353-355. && $$ SYNOPSIS...JM/PW NEAR TERM...MALOIT/MET/PW SHORT TERM...PW LONG TERM...JM AVIATION...GOODMAN/MPS MARINE...JC/JM/MET/PW HYDROLOGY...JM/PW TIDES/COASTAL FLOODING... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1158 PM EST THU JAN 2 2014 .SYNOPSIS... DEEPENING LOW PRESSURE PASSES TO THE SOUTH TONIGHT...THEN DEPARTS TO THE EAST FRIDAY. HIGH PRESSURE BUILDS FRIDAY NIGHT. HIGH PRESSURE WILL MOVE EAST AND OFFSHORE THIS WEEKEND WITH ANOTHER LOW DEVELOPING ALONG THE APPALACHIANS SUNDAY. THIS WILL DEEPEN TO THE WEST OF THE REGION WITH A COLD FRONT MOVING ACROSS MONDAY. ANOTHER ARCTIC AIRMASS BUILDS IN BEHIND IT AS WESTERN CANADA HIGH PRESSURE BUILDS TO THE SOUTH AND WEST OF THE REGION THROUGH MID NEXT WEEK. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... TEMPERATURES ARE FALLING OFF MORE RAPIDLY THAN FORECAST - HAVE ADJUSTED DOWNWARD BASED ON HRRR 2-M TEMPERATURES WHICH SEEM TO AVE BEST HANDLE ON CURRENT TRENDS. AS A RESULT - COULD END UP WITH SLIGHTLY HIGHER SNOW TO LIQUID RATIOS - SO ADDED LOCALLY HIGHER AMOUNTS POSSIBLE TO THE WSW TEXT. SPS OUT FOR SNOW BAND IMPACTING S NASSAU AND SUFFOLK - WITH RATES 1-2 INCH/HR. WILL MONITOR AND UPDATE AMOUNTS IF NEEDED. AT 4Z A 996 HPA LOW WAS LOCATED ABOUT 210 MILES S OF KMTP LIFTING NNE PER LATEST PRESSURE FALLS...WITH RAPID DEEPENING EXPECTED TO CONTINUE. WITH THE STEEP PRESSURE FALLS DUE EXPECT WINDS TO CONTINUE TO INCREASE OVER THE AREA. DEPENDING ON HOW WINDS AND VISIBILITIES TREND - THERE IS A CHANCE FOR A SHORT FUSED EXPANSION OF THE BLIZZARD WARNING - WITH MOST LIKELY CANDIDATES BEING SE CT AND POSSIBLY NYC. EXPECT HEAVIEST SNOWFALL ACROSS THE AREA GENERALLY THROUGH 9Z THEN A TAPERING OFF FROM W TO E. MODEL OUTPUT FOR TONIGHT REMAINS FAIRLY CLOSE...WITH GFS AND ECMWF A BIT WETTER THAN NAM/WRF. SREF ENSEMBLE WOULD SUGGEST A QPF BLEND IS PERHAPS THE WAY TO GO AT THIS TIME. QPF OF AROUND 1/2 INCH TO 3/4 OF AN INCH IS EXPECTED. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/... VERY COLD AIR THIS TIME FRAME. MORNING SNOW ENDS FROM WEST TO EAST AS THE UPPER TROUGH PIVOTS ACROSS THE NORTHEAST AND THE DEEPENING COASTAL LOW DEPARTS. SNOW ACCUMULATIONS 5 TO 10 INCHES...WITH PERHAPS SOME HIGHER AMOUNTS OVER LI PER LOW TRACK/HEAVIEST SNOW CLIMATOLOGY. WINDY CONDITIONS WILL RESULT IN BLOWING SNOW THROUGH THE MORNING AND INTO THE AFTERNOON. SKIES CLEAR DURING THE AFTERNOON...AGAIN FROM WEST TO EAST. TEMPS RISE LITTLE DURING THE DAY...AND IN FACT REMAIN NEARLY STEADY BEFORE DROPPING LATER IN THE DAY. MAX TEMPS IN THE TEENS EXPECTED. FOR FRIDAY NIGHT...A RIDGE OF HIGH PRESSURE BUILDS IN. AS WINDS LIGHTEN AND SKIES REMAIN CLEAR...TEMPS WILL PLUMMET INTO THE SINGLE DIGITS AND BELOW ZERO ACROSS THE REGION. WENT CLOSER TO COLDER MAV DATA...WHICH MAY NOT EVEN BE COLD ENOUGH AS MOS TRENDS TOWARD CLIMATOLOGY AND DOES NOT USUALLY HANDLE IMPACTS OF A FRESH SNOWPACK WELL. HOWEVER...SOME WAA MID AND HIGH CLOUDS APPROACH LATE AT NIGHT...WHICH COULD HAVE A MINOR IMPACT ON TEMPS. && .LONG TERM /SATURDAY THROUGH THURSDAY/... THE JET STREAM LIFTS GRADUALLY NORTH OF THE REGION THIS WEEKEND BUT WILL DIVE BACK SOUTH OF THE REGION FOR NEXT WEEK. A RIDGING TREND IN THE MID LEVELS MUCH OF THE WEEKEND WITH DECREASING HEIGHTS SUNDAY AFTERNOON INTO NEXT WEEK WITH A MUCH COLDER AIRMASS APPROACHING. AT THE SURFACE...THE ARCTIC HIGH PRESSURE WILL BE CENTERED ACROSS THE REGION SATURDAY MORNING AND WILL PUSH OFFSHORE THROUGH THE DAY. THIS WILL CONTINUE TO MOVE EAST THROUGH THE WEEKEND...WITH A CONTINUANCE OF RETURN SOUTHERLY FLOW. THE RESULT WILL BE A MODERATION OF THE AIRMASS...ALTHOUGH WITH LIMITED MIXING HEIGHTS SATURDAY...ONLY TO BETWEEN 1000 AND 950 MB. HIGHS ARE FORECAST TO STILL BE ABOUT 10 DEGREES BELOW NORMAL. THE MODERATION WILL BE MORE REMARKABLE AT NIGHT...ESPECIALLY ALONG THE COAST WITH THE INCREASINGLY ONSHORE FLOW AS HIGH PRESSURE CONTINUE TO MOVES OFFSHORE. LOWS SATURDAY NIGHT ARE FORECAST TO BE CLOSER TO NORMAL BUT STILL LIKELY BELOW NORMAL ACROSS THE INTERIOR WITH LIGHTER WINDS THERE. A REMARKABLE REBOUND IN TEMPERATURES FOR SUNDAY WITH THE CONTINUED RETURN SOUTHERLY FLOW. HOWEVER...TEMPERATURES FREEZING OR BELOW IN THE MORNING WITH NEXT WAVE OF LOW PRESSURE TO OUR WEST APPROACHING WILL LEAD TO WARMER TEMPERATURES ALOFT. THIS WILL PRESENT A CHANCE FOR A WINTRY MIX TO START...CHANGING TO RAIN FROM SOUTHEAST TO NORTHWEST LATER IN THE DAY AS WARMER AIR RIDES INTO THE AREA. MAINLY RAIN AT NIGHT AHEAD OF THE COLD FRONT AND ANOMALOUSLY WARM AIR ADVECTING OVER THE AREA. ALONG WITH THIS WILL ALSO BE ADVECTION FOG...PATCHY IN NATURE DURING THE AREA BUT LIKELY GROWING IN AREA AT NIGHT...ESPECIALLY IN ANY LULLS IN RAIN ACTIVITY. TEMPERATURES WILL BE ON A NON-DIURNAL TREND...RISING SLOWLY SUNDAY EVENING. A PERIOD OF MODERATE RAIN IS FORECAST SUNDAY NIGHT INTO EARLY MONDAY. THIS RAIN COULD BE POTENTIALLY HEAVY AT TIMES WITH PRECIPITABLE WATER VALUES OF SLIGHTLY OVER 1 INCH...WHICH IS CLOSE TO 2 STANDARD DEVIATIONS ABOVE NORMAL FOR THE MONTH OF JANUARY. THE RAIN WILL THEN TAPER OFF FROM WEST TO EAST DURING THE DAY MONDAY WITH SHOWER ACTIVITY BEHIND THE FRONT. SHARP COLD AIR ADVECTION ON A STRENGTHENING NORTHWEST FLOW WILL ALLOW FOR SOME SNOW SHOWERS AS WE GO THROUGH THE DAY. MAX TEMPERATURES FOR MONDAY WILL LIKELY BY SET IN THE MORNING WITH LOWERING TEMPERATURES FOR THE REMAINDER OF THE DAY. ANOTHER VERY COLD AIRMASS BUILDS IN THROUGH MID NEXT WEEK WITH MUCH BELOW NORMAL TEMPS. HIGH PRESSURE FROM WESTERN CANADA WILL BE BUILDING TO THE SOUTH AND WEST OF THE REGION. ANOTHER ROUND OF SNOW SHOWERS WILL BE POSSIBLE ACROSS EASTERN LONG ISLAND AND SOUTHEAST CT TUESDAY INTO TUESDAY EVENING AS WELL AS NEXT THURSDAY AS PERIODIC SHORTWAVES ALOFT MOVE ACROSS. TOWARDS THE END OF NEXT WEEK THE DEEP ANOMALOUS TROUGH PATTERN CHANGES TO MORE OF A QUASI-ZONAL FLOW. ALSO OF NOTE IS THAT WINDS WILL CONTINUE TO BE GUSTY FROM A WESTERLY DIRECTION MONDAY THROUGH WEDNESDAY. WIND CHILLS FORECAST COULD REACH 0 TO -10 DEGREES F AT TIMES LATE MONDAY NIGHT THROUGH EARLY WEDNESDAY. UNCERTAINTY IS HIGHER WITH THE FORECAST SUNDAY NIGHT THROUGH MONDAY. VAST DIFFERENCES ARE EVIDENT WITHIN THE ECMWF AND GFS SOLUTIONS. THESE DIFFERENCES ALSO ARE APPARENT WITHIN THE GFS ENSEMBLE AND MUCH OF ITS MEMBERS WITH THE LAST TWO RUNS. THE FORECAST CURRENTLY SIDES MORE WITH THE ECMWF SOLUTION WITH A SLOWER FRONTAL SPEED AND MORE WESTERN TRACK OF THE LOW SUNDAY INTO MONDAY. && .AVIATION /06Z FRIDAY THROUGH TUESDAY/... ***HIGH IMPACT WINTER STORM TONIGHT INTO FRIDAY*** SNOW OVERSPREADS THE TERMINALS WITH IFR/LIFR CONDITIONS. SNOW BECOMES MODERATE TO HEAVY WITH LIFR/VLIFR CONDITIONS AND SNOWFALL RATES OF 1 TO 2 INCHES PER HOUR FROM AROUND 05Z-12Z. ALTHOUGH FALLING SNOW WILL TAPER OFF FROM 12Z-14Z FROM WEST TO EAST...BLOWING SNOW WILL CONTINUE TO IMPACT THE TERMINALS WITH IFR VSBYS UNTIL THE MIDDLE OF THE DAY. CONDITIONS IMPROVE TO VFR BY EARLY AFTERNOON. TOTAL SNOW ACCUMULATIONS WILL RANGE FROM 6-8 INCHES OVER WESTERN TERMINALS AND FROM 8-10 INCHES OVER EASTERN LONG ISLAND AND SOUTHEAST CT. N-NE WINDS (020-040 MAG) AROUND 20 KT WITH GUSTS 25-30 KT WILL BACK TO THE NORTH (350-010 MAG) AND INCREASE TO 20-30 KT WITH 30-40 KT GUSTS BY 05Z. WINDS BACK FURTHER TO THE NW (330-350 MAG) AFTER 12Z FRIDAY. NW WINDS 20-25G25-35KT WILL CONTINUE FOR MUCH OF FRIDAY BEFORE DIMINISHING BY EARLY EVENING. .OUTLOOK FOR 00Z SATURDAY THROUGH TUESDAY... .FRIDAY NIGHT...VFR. WINDS DIMINISH TO 10 KT OR LESS BY 06Z. .SATURDAY-SATURDAY NIGHT...VFR. SW WINDS LESS THAN 10 KT. .SUNDAY...MVFR POSSIBLE IN THE AFTERNOON. RAIN POSSIBLE ACROSS KNYC/COASTAL CT/LONG ISLAND/NE NJ TERMINALS AND RAIN/SNOW POSSIBLE ACROSS THE INTERIOR. .SUNDAY NIGHT-MONDAY MORNING...IFR CONDITIONS LIKELY IN RAIN. SOUTH WINDS GUSTING TO 20-30 KT LATE SUNDAY NIGHT/MONDAY MORNING. .MONDAY AFTERNOON...CONDS IMPROVING TO VFR. WINDS BACK TO THE WEST. 20-30 KT GUSTS POSSIBLE. .TUESDAY...VFR. WEST WINDS 15-20 KT WITH 20-30 KT GUSTS. && .MARINE... MINOR CHANGES THIS UPDATE TO REFLECT THE LATEST TRENDS IN OBSERVATIONS AND GUIDANCE. BASED ON DEEPENING DID ADD OCCASIONAL GUSTS TO 50 KT FOR THE TWO EASTERN COASTAL OCEAN ZONES OVERNIGHT. WIND AND GUSTS CONTINUE TO INCREASE OVERNIGHT AS THE LOW DEEPENS AND TRACK SOUTH OF THE WATERS. VERY ROUGH CONDITIONS ARE ANTICIPATED ON THE WATERS THROUGH FRIDAY. DEEPENING LOW PRESSURE PASSES TO THE SOUTH AND EAST THIS TIME FRAME...WITH GALES EXPECTED TONIGHT INTO FRIDAY. FREEZING SPRAY REMAINS A CONCERN AS WELL. GALE CONDITIONS END LATER FRIDAY AS HIGH PRESSURE BUILDS. WINDS DIMINISH QUITE A BIT FRIDAY NIGHT AS THE RIDGE BUILDS. ROUGH SEAS TONIGHT AND FRIDAY SLOWLY SUBSIDE LATE FRIDAY AND FRIDAY NIGHT. SUB SCA SAT MORNING INCREASES TO SCA SOUTHEAST OF LI LATE SAT THROUGH SUN MORNING. THIS WILL BE MAINLY ACROSS THE EASTERN OCEAN ZONES. A BRIEF RETURN TO BELOW SCA CONDITIONS WILL BE FOLLOWED BY ANOTHER ROUND OF SCA SUNDAY NIGHT INTO NEXT WEEK. && .HYDROLOGY... BETWEEN 1/2 TO 3/4 OF AN INCH OF LIQUID EQUIVALENT IS EXPECTED THROUGH FRIDAY...ALL FALLING AS SNOW. ANOTHER WIDESPREAD SIGNIFICANT PRECIP EVENT IS POSSIBLE SUNDAY THROUGH EARLY MONDAY...MOSTLY IN THE FORM OF RAIN. THE HEAVY RAIN COULD COMBINE WITH RESIDUAL SNOW COVER TO PRODUCE SOME FLOODING. GENERAL ESTIMATES OF EVENT TOTAL LIQUID AMOUNTS FROM A MODEL CONSENSUS ARE AROUND 0.5 TO 1 INCH. && .TIDES/COASTAL FLOODING... THE HEIGHT OF THE STORM COMES THRU OVERNIGHT...AS A RESULT PEAK WINDS DO NOT LINE UP WITH THE HIGH TIDE CYCLES IN THE CITY AND ALONG THE GREAT S BAY. ADVISORY WILL EXPIRE AT MIDNIGHT FOR GREAT SOUTH BAY - WITH MINOR FLOODING MEASURED AT AREA GAUGES THERE. ACROSS THE SOUND...HIGH TIDE IS AROUND MIDNIGHT...SO THIS LINES UP BETTER WITH THE GALE FORCE WINDS. SEAS HAVE ALREADY BEEN REPORTED AT 4 FT ON THE SOUND...SO EXPECT WAVES COULD REACH AS HIGH AS 3-6 FT ON THE N FACING SOUND COASTS. AS A RESULT...THIS SHOULD COMBINE WITH THE SURGE TO PRODUCE MODERATE FLOODING. A WRNG HAS THEREFORE BEEN ISSUED FROM THE BRONX AROUND TO CNTRL SUFFOLK. DUE TO OFFSHORE COMPONENT WINDS...EXPECTING THE IMPACTS TO BE LESSER FROM WESTCHESTER TO CT...SO AN ADVY ISSUED FOR THOSE SPOTS. AN INCREASE OF A HALF FT IN SURGE ABV THE HIGHEST GUIDANCE WILL BE REQUIRED FOR THESE AREAS TO REACH MODERATE. AN ADVY HAS ALSO BEEN POSTED FOR SERN LI. THIS IS PRIMARILY FOR THE N FACING PORTIONS OF THE S FORK AND SUSCEPTIBLE AREAS ALONG THE ATLANTIC WHERE WAVE ACTION WILL SUPPLEMENT THE SURGE. THERE IS CONSIDERABLE SPREAD WITH THE GUIDANCE FOR THE FRIDAY MRNG/AFTN HIGH TIDE CYCLE...PARTICULARLY ACROSS THE WRN SOUND WHERE THE ETSS IS TRYING TO HOLD ONTO A SIGNIFICANT AMOUNT OF WATER. BECAUSE THIS SOLN IS AN OUTLIER...MINOR OR BLW IS THE MOST LIKELY OUTCOME FOR ALL AREAS ATTM. MINOR BEACH EROSION CAN BE EXPECTED ALONG PORTIONS OF THE SOUND AND WRN OCEAN...WITH MODERATE EROSION ALONG THE CNTRL AND ERN OCEANFRONT. && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...WINTER STORM WARNING UNTIL 1 PM EST FRIDAY FOR CTZ005>012. COASTAL FLOOD ADVISORY UNTIL 2 AM EST FRIDAY FOR CTZ009-010. NY...BLIZZARD WARNING UNTIL 1 PM EST FRIDAY FOR NYZ078>081-177-179. WINTER STORM WARNING UNTIL 1 PM EST FRIDAY FOR NYZ067>075-176- 178. COASTAL FLOOD ADVISORY UNTIL 2 AM EST FRIDAY FOR NYZ071. COASTAL FLOOD ADVISORY UNTIL MIDNIGHT EST TONIGHT FOR NYZ080- 081-179. COASTAL FLOOD WARNING UNTIL 2 AM EST FRIDAY FOR NYZ073-078-176- 177. NJ...WINTER STORM WARNING UNTIL 1 PM EST FRIDAY FOR NJZ002-004-006- 103>108. MARINE...GALE WARNING UNTIL 6 PM EST FRIDAY FOR ANZ330-335-338-340-345- 350-353-355. && $$ SYNOPSIS...JM/PW NEAR TERM...MALOIT/MET/PW SHORT TERM...PW LONG TERM...JM AVIATION...MPS MARINE...JC/JM/MET/PW HYDROLOGY...JM/PW TIDES/COASTAL FLOODING... EQUIPMENT...
AREA FORECAST DISCUSSION
NWS MELBOURNE FL
1020 AM EST FRI JAN 3 2014 .DISCUSSION... ...HAZARDOUS MARINE CONDITIONS THROUGH TONIGHT... ...WINDY AND MUCH COLDER TODAY... CURRENT...VISIBLE/WATER VAPOR SATELLITE IMAGERY SHOWS ABUNDANT MID AND HIGH LEVEL CLOUD COVER CONTINUING ACROSS ECFL THIS MORNING. BOTH RUC ANLYS FIELDS AND THE MORNING RAOBS FROM JAX/TBW/XMR SHOW NEARLY SATURATED AND DIVGT CONDITIONS IN THE H50-H20 LAYER ACTING TO PRODUCE THOSE CLOUDS. ALSO...AN EXPANSIVE AREA OF CAA-INDUCED CLOSED-CELL MARINE STRATOCU IS ALREADY IMPINGING UPON COASTAL VOLUSIA AND BREVARD COUNTIES. CCAFS 915MHZ WIND PROFILER DATA IS SUPPORTIVE OF THIS....SHOWING 0-2KM WINDS ALREADY STARTING TO VEER TO 360-010. STRONG CAA HAS BEEN WINNING OUT OVER WEAK EARLY JAN/EARLY MORNING DIURNAL HEATING AS TEMPS AREAWIDE HAVE CONTINUED TO EITHER SLOWLY DROP OR HOLD STEADY IN THE 2-3HRS SINCE SUNRISE. THIS HAS ALSO KEPT WCI VALUES IN LAKE/VOLUSIA COS IN THE L30S...SO HAVING THE NPW/WCA ISSUED UNTIL 10AM TODAY WAS AN EXCELLENT CALL BY THE THU AFTERNOON SHIFT. REST OF TODAY...BLUSTERY AND CHILLY FOR MOST OF THE AREA. NORTHERLY WINDS IN THE 15-25MPH RANGE WILL BE VERY SLOW TO RELAX AS THEY TRY AND VEER TO NNE THROUGH LATE AFTERNOON. TEMPS WILL STRUGGLE TO RISE IN THE CAA PATTERN WITH MAXES RANGING FROM ~50F AROUND LAKE GEORGE AND THE OCALA FOREST...TO THE LOW 60S ACROSS MARTIN COUNTY...WHICH MEANS 50S FOR MOST OF THE CWA. MADE SOME ADJUSTMENTS TO THE TEMP... WIND AND SKY COVER GRIDS TO ACCOUNT FOR CURRENT CONDITIONS. THIS WILL CHANGE ALL THE COASTAL COUNTIES TO "MOSTLY CLOUDY" OR BECOMING SO BY THIS AFTERNOON DUE TO THE AFOREMENTIONED MARINE CLOUDS. && .AVIATION...VFR CIGS AOB BKN-OVC150 WILL GRADUALLY LIFT ENE AWAY FROM THE AREA AS H25 JET STREAK/ATTENDANT MOISTURE DOES LIKEWISE. MVFR CIGS BKN-OVC025-030 CURRENTLY INVADING OMN-DAB-EVB-TIX WILL CONTINUE TO SPREAD SWD ALONG THE MLB-VRB-FPR CORRIDOR AS 0-1KM WINDS CONTINUE TO VEER TODAY/TONIGHT. && .MARINE...GIVEN CURRENT WIND/SEA CONDITIONS AT 41009/41012...AS WELL AS WINDS AT SPGF1...THOUGHT IT WAS PRUDENT TO EXTEND THE GALE WARNING (FOR FREQUENT GUSTS TO GALE FORCE) INTO THIS AFTERNOON. OTHERWISE...CURRENT FORECAST FOR WINDS/SEAS CONTINUE ON TRACK. && UPDATE/AVIATION...CRISTALDI LONG TERM/IMPACT WX...WEITLICH && .PREV DISCUSSION... /ISSUED 400 AM EST FRI JAN 3 2014/ TONIGHT...RAPID AIRMASS MODIFICATION WILL OCCUR AS WINDS VEER ONSHORE...PUSHING WARM OCEAN AIR AND A BLANKET OF MARINE STRATOCU BACK ACRS CENTRAL FL. SO RAPID THE MODIFICATION WILL BE THAT SOME "MIN" TEMPS ALONG THE SPACE AND TREASURE COASTS TONIGHT ACTUALLY MAY BE WARMER THAN THIS AFTN "MAX" TEMPS...CERTAINLY A DIFFERENCE OF ARND 5F BTWN THE TWO WILL BE COMMON. INTERIOR TEMPS WILL REMAIN A FEW DEGS BLO AVG ALONG AND N OF THE I-4 CORRIDOR (L/M40S)...WINDS EXPECTED TO DIMINISH BLO 10MPH AFT SUNSET...LCL CRITERIA FOR A WIND CHILL ADVISORY NOT EXPECTED. PRECIP NOT COMPLETELY OUT OF THE QUESTION....BUT WITH SUCH A STRONG CAP IN PLACE...VERTICAL MOTION WILL BE WELL BLO 10KFT. ANY IMPACT FROM SUCH LOW TOPPED SHRAS WOULD BE MINIMAL...WILL KEEP THE FCST DRY THRU DAYBREAK. SATURDAY...SFC HIGH PRESSURE NEAR THE MID ATLC WILL PUSH OFFSHORE ALLOWING FOR MARINE CLOUDINESS TO PUSH ONSHORE ACROSS E CENTRAL FL. SOME ISOLATED LIGHT SHOWERS MAY MOVE ONSHORE ALONG THE IMMEDIATE COAST AND A MID LVL S/W TROUGH ACROSS THE SE GULF OF MEXICO WILL SPREAD CLOUDINESS ACROSS SRN AREAS IN THE AFTERNOON WHERE SOME LATE DAY SHOWERS MAY ALSO BREAK OUT ACROSS OKEECHOBEE COUNTY. THE ONSHORE FLOW OFF THE RELATIVELY WARM ATLC WILL ALLOW FOR A 15-20 WARM UP IN TEMPS FROM VERY COOL FRIDAY READINGS. WILL SEE HIGHS AROUND 70 NORTH COASTAL AREAS TO MID 70S SRN SECTIONS. SAT NIGHT...MID LVL DISTURBANCES WILL TRACK NE ACROSS SRN FL WITH VEERING LOW LVL FLOW. NAM KEEPS MOST OF THE HEAVIER PRECIP OFF THE TREASURE COAST WHILE 18Z/00Z GFS ALLOWS SHOWERS TO MOVE ONSHORE WITH HEALTHIER QPF FROM BREVARD SOUTH TO MARTIN COUNTY. WILL LEAN TWD THE GFS AND SHOW HIGH CHC POPS IN THESE AREAS WITH LOWER CHC POPS TO SLGT CHC POPS ACROSS NRN INTERIOR SECTIONS. LOWS IN THE MID-UPR 50S NORTH AND MID 60S S CSTL. SUNDAY...LOW LVL SW FLOW AHEAD OF THE NEXT FRONT AND ADEQUATE MOISTURE LEVELS WILL TRIGGER SCATTERED AFTERNOON SHOWERS. WILL KEEP RAIN CHANCES CLOSE TO MOS AROUND 30 PCT FOR LAKE COUNTY TO 50 PCT ALONG THE TREASURE COAST. HIGHS WILL WARM INTO THE UPPER 70S TO LOWER 80S. MONDAY....A REINFORCING TROUGH DROPS INTO THE UPPER MIDWEST ON MONDAY AND ALLOWS ANOTHER COLD FRONT TO MOVE DOWN THE FL PENINSULA. THE FAST MOVING FRONT WILL NOT HAVE SUBSTANTIAL PREFRONTAL MOISTURE TO WORK WITH...EXCEPT ACROSS S FL. EXPECT ISOLATED SHOWERS ALONG THE FRONT ACROSS NRN AREAS AND SLIGHTLY HIGHER COVERAGE ACROSS SRN SECTIONS. HIGHS WILL RANGE FROM THE 60S NORTH TO LOWER 70S SRN AREAS. BREEZY NW WINDS WILL DEVELOP AFTER THE FRONTAL PASSAGE. MONDAY NIGHT-TUESDAY NIGHT...SFC HIGH PRESSURE WILL BUILD FROM THE THE LWR MS VALLEY INTO THE SE STATES EARLY NEXT WEEK WITH THE FIRST PROLONGED STRETCH OF COLD NORTHERLY LOW LVL FLOW FOR AROUND 36 HOURS THIS WINTER SEASON. THIS WILL PRODUCE TWO COLD NIGHTS EARLY NEXT WEEK WITH LOW INTO THE 30S ACROSS MUCH OF NORTHERN AND INTERIOR SECTIONS OF E CENTRAL FL AND 40S ACROSS SRN COASTAL AREAS. HIGHS TUESDAY WILL ONLY BE IN THE 50S...EXCEPT INTO THE LOWER 60S ACROSS THE SRN TREASURE COAST. WED-FRI...HIGH PRESSURE WILL MOVE TOWARD THE MID ATLC ON WEDNESDAY AND OFFSHORE THROUGH LATE WEEK ALLOW LOW LVL WINDS TO VEER TO ONSHORE OFF THE RELATIVELY MILD ATLANTIC WATERS. A GRADUAL WARMING TREND IS EXPECTED BY THU INTO FRI WITH HIGHS RETURNING TO MID TO UPPER 70S MOST AREAS. EXPECT MAINLY DRY WEATHER...EXCEPT FOR A SLIGHT SHOWER CHANCE ON THURSDAY. && .AVIATION... THRU 03/12Z...W/NW SFC WND G21-25KT...AREAS CIGS BTWN FL020-030 LCL CIGS BTWN FL010-020. BTWN 03/12Z-03/22Z...N/NW SFC WND G22-26KTS... VFR ALL SITES. AFT 03/22Z...VFR CIGS BTWN FL030-040 COASTAL SITES... BTWN FL040-050 INTERIOR SITES. && .MARINE... TODAY-TONIGHT...DANGEROUS BOATING CONDITIONS AS A POST FRONTAL HI PRES RIDGE EXTENDING FROM THE BAY OF CAMPECHE TO THE GREAT LAKES GENERATES A STRONG N/NW BREEZE WITH NEAR GALE STRENGTH OVER THE OFFSHORE WATERS N OF SEBASTIAN INLET. OFFSHORE DATA BUOYS ALREADY MEASURING 25-30KT NW WINDS WITH FRQT GUSTS AOA GALE FORCE. SEAS HAVE YET TO RESPOND TO THE INCREASED WINDS BUT WILL BUILD STEADILY TO 6-8FT NEARSHORE AND UP TO 12FT OFFSHORE THRU THE DAY AS WINDS VEER TO THE N/NE AND COUNTER THE SRLY GULF STREAM CURRENT. WINDS WILL DIMINISH BLO SCA CRITERIA AFT SUNSET AS THE POST FRONTAL RIDGE PUSHES INTO THE W ATLC AND BEGINS TO WEAKEN...THOUGH OVERALL CONDITION WILL REMAIN QUITE POOR. CURRENT GALE/SCA CONFIGURATION LOOKS GOOD...BUT WILL EXTEND THE EXPIRATION TIME FOR THE SCA TO 09Z AREAWIDE...AND TO 15Z FOR THE OFFSHORE LEG. EAST WINDS AROUND 15 KNOTS ON SATURDAY ARE EXPECTED WITH SEAS SLOWLY DIMINISHING TO 4-6 FT. SE/S FLOW AT 10-15 KNOTS ON SUNDAY WITH HIGHER PRECIP COVERAGE EXPECTED ACROSS THE SRN WATERS. NEXT FRONT WILL BRING HAZARDOUS BOATING CONDITIONS EARLY NEXT WEEK AS FRONT MOVES THROUGH THE WATERS DURING THE DAY AND WINDS INCREASE TO 25 KNOTS FROM THE NORTHWEST. EXPECT SEAS TO BUILD TO 10-13 FEET BY MONDAY NIGHT INTO EARLY TUESDAY AFTERNOON THE OFFSHORE AND GULF STREAM WATERS. && .FIRE WEATHER...MIN RHS WILL APPROACH 35 PERCENT ACROSS THE INTERIOR WITH BREEZY N WINDS. ERC VALUES ARE CURRENTLY MISSING BUT WITH SOME RAIN YESTERDAY WILL HOLD OFF ANY RED FLAG HEADLINES. ONSHORE FLOW SATURDAY WILL MITIGATE ANY LOW RH CONCERNS. STRONG AND GUSTY NW WINDS NEXT MONDAY AND LOW RH MAY REQUIRE FIRE WEATHER HEADLINES EARLY NEXT WEEK. && .CLIMATE...TEMPERATURES SHORTLY AFTER MIDNIGHT IN THE UPPER 60S AT ORLANDO/MELBOURNE AND VERO BEACH AND IN THE UPPER 50S AT DAYTONA BEACH WILL BE THE CALENDAR DAY HIGH TEMPERATURES AS A COLD FRONT BRINGS MUCH COLDER TEMPERATURES TODAY. && .PRELIMINARY POINT TEMPS/POPS... DAB 50 47 70 60 / 10 10 20 20 MCO 56 46 73 59 / 0 10 10 30 MLB 56 53 73 64 / 10 10 20 50 VRB 59 54 74 63 / 10 10 20 50 LEE 50 40 70 57 / 0 10 10 20 SFB 53 45 72 59 / 0 10 10 20 ORL 54 46 72 60 / 0 10 10 30 FPR 60 55 74 64 / 10 10 20 50 && .MLB WATCHES/WARNINGS/ADVISORIES... FL...LAKE WIND ADVISORY UNTIL 4 PM EST THIS AFTERNOON 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 UNTIL 4 AM SATURDAY FROM FLAGLER BEACH TO JUPITER INLET OUT 20 NM. GALE WARNING UNTIL 4 PM THIS AFTERNOON FROM FLAGLER BEACH TO JUPITER INLET 20 TO 60 NM OFFSHORE. SMALL CRAFT ADVISORY FROM 4 PM THIS AFTERNOON UNTIL 10 AM SATURDAY FROM FLAGLER BEACH TO JUPITER INLET 20 TO 60 NM OFFSHORE. && $$
AREA FORECAST DISCUSSION
NWS JACKSON KY
1207 AM EST FRI JAN 3 2014 .UPDATE... ISSUED AT 1206 AM EST FRI JAN 3 2014 UPDATED THE FORECAST TO EXTEND THE WINTER WEATHER ADVISORY UNTIL 2 AM FOR THE BLUEGRASS AND FOR AREAS WEST OF I 75 SINCE IT WAS STILL SNOWING. THE BLOWING SNOW WILL CONTINUE TO BE A PROBLEM FOR ROAD CREWS TONIGHT BECAUSE THE SNOW WILL CONTINUE TO BLOW ACROSS THE ROADWAYS WHEN THEY ARE CLEARED. THE NEXT PROBLEM IS THE WIND CHILL CAUSED BY THE WIND AND THE COLD AIR THAT CONTINUES TO POUR INTO THE AREA. THE REST OF THE FORECAST IS ON TRACK. UPDATE ISSUED AT 1027 PM EST THU JAN 2 2014 SURFACE ANALYSIS AS OF 03Z STILL FEATURES NORTHWEST FLOW IN THE LOWER LEVELS THOUGH THE OHIO VALLEY WITH A STRONG GRADIENT MAINTAINED AS WINDS CONTINUE OUT OF THE NORTH NORTHWEST AT 15 TO 25 KNOTS THROUGH THE AREA. ENOUGH LOW LEVEL MOISTURE CONTINUES TO STREAM SOUTH FROM THE GREAT LAKES REGION HITTING THE RUGGED TERRAIN OF THE EASTERN KENTUCKY. THIS...ALONG WITH JUST ENOUGH INSTABILITY OF 10 TO 20 JOULES AT THE SURFACE...HAS ALLOWED FOR CONTINUED BANDS OF SNOW SHOWERS LASTING THROUGH THE NIGHT HOURS AS SOME ISOLATED AREAS HAVE SEEN A BIT MORE ACCUMULATION THAN EXPECTED...ESPECIALLY LOCATIONS WHERE TERRAIN HAS PROFOUND EFFECTS. THIS ALONG WITH THE ALREADY TREACHEROUS ROADS DUE TO SNOWFALL...BLACK ICE...AND BLUSTERY CONDITIONS...HAS LEAD TO THE DECISION TO EXTEND THE WINTER WEATHER ADVISORY UNTIL MIDNIGHT FOR THE NORTHWEST AND SOUTHWEST COUNTIES AND AS WELL AS THE MIDDLE TIER COUNTIES. ALSO CONTINUING A BIT LONGER TONIGHT WILL BE THE STRONG NORTHWEST WINDS. THE NAM AND GFS AGREE KEEPING THE STRONGER GRADIENT THROUGH THE NIGHT SO HAVE BUMPED UP THE 10 TO 15 KNOT WINDS AND GUSTS TO 20 THROUGH AT LEAST 09Z AND BECOMING LIGHT BY DAWN. THE WIND COMBINED WITH THE ARCTIC AIR MASS SETTLING IN WILL DROP SOME WINDS CHILLS BELOW ZERO TONIGHT. HAVE UPDATED THE ZFP AND WSW TO ADDRESS THESE IMPACT TONIGHT. UPDATE ISSUED AT 627 PM EST THU JAN 2 2014 SNOW SHOWERS WILL CONTINUE TO PUSH THROUGH EASTERN KENTUCKY THROUGH THE NIGHT. SOME SMALLER INTENSE BANDS OF SNOW HAVE SET UP AS WELL. AS OF RIGHT NOW...TEMPS...WINDS AND SNOWFALL AMOUNTS LOOK TO BE ON TRACK. HAVE FRESHENED UP THE GRIDS WITH THE MOST CURRENT OBSERVATIONS AND SENT THEM TO NDFD. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 310 PM EST THU JAN 2 2014 19Z SFC ANALYSIS SHOWS THE NOW DEEPER LOW JUST EAST OF KENTUCKY WITH THE TIGHT ISOBARS CROSSING INTO EAST KENTUCKY. THIS IS RESULTING IN STIFF NORTHWEST WINDS WITH GUSTS TO 30 MPH BRINGING IN THE MUCH COLDER AIR. RAIN HAS CHANGED TO SNOW ACROSS WESTERN PARTS OF THE AREA AND NOW HERE AT JKL. ANOTHER HOUR OR SO IT WILL BE SNOW EVERYWHERE...IN PLACES THAT STILL ARE PRECIPITATING. THERE IS CURRENTLY A DISTINCT BACK EDGE TO THIS POST FRONTAL SNOW AREA. HOWEVER...ANOTHER DECENT BATCH OF SNOW IS DROPPING THROUGH SOUTHERN INDIANA ON RADAR AND THIS SHOULD MOVE OVER OUR CWA THIS EVENING. TEMPERATURES CURRENTLY VARY FROM THE LOW 40S NEAR MIDDLESBORO TO AROUND FREEZING OVER OUR WESTERN COUNTIES. DEWPOINTS ARE PEGGED TO THE TEMPERATURE IN MOST SPOTS WITH THE GUSTY NORTHWEST WINDS NOW REPORTED AT MOST OBS SITES IN THE AREA. THE MODELS ARE IN GOOD AGREEMENT ALOFT WITH THE SHARP AND DEEP TROUGH CURRENTLY SWINGING THROUGH THE AREA. HEIGHTS WILL THEN QUICKLY CLIMB LATE TONIGHT INTO FRIDAY IN THE WAKE OF THE DEPARTING WAVE. FAST... MOSTLY ZONAL...FLOW FOLLOWS INTO SATURDAY MORNING WITH ONLY VERY MINOR BITS OF ENERGY FLOATING BY IN THE AIR STREAM AT MID LEVELS. WITH NO GREAT DISTINCTION IN THE MODELS HAVE FAVORED A BLEND WITH A LEAN TOWARD THE HRRR AND NAM12 FOR NEAR TERM SPECIFICS. SENSIBLE WEATHER WILL FEATURE A BAND OF SNOW MOVING THROUGH EAST KENTUCKY ASSOCIATED WITH THE RETURN OF AN ARCTIC AIR MASS. SOME PLACES...PARTICULARLY IN THE SOUTHWEST...WILL SEE A LULL IN THE SNOW FOR SEVERAL HOURS INTO THE EVENING WITH A POSSIBLE RESURGENCE AROUND 00Z AS THAT SNOW OVER INDIANA MOVES INTO OUR CWA. EVEN IN THOSE PLACES...HAZARDOUS CONDITIONS WILL EXIST AS WET ROADS A THREAT TO ICE OVER SINCE THE ARCTIC AIR QUICKLY DROPS TEMPERATURES INTO THE 20S FROM WEST TO EAST LATE THIS AFTERNOON AND EARLY EVENING. ACCORDINGLY...WILL MAINTAIN THE CURRENT ADVISORY STRUCTURE AND FOCUS ON THE REFREEZE FOR WESTERN MOST PLACES THAT WILL NOT GET MUCH OF THE UPSLOPE. OTHERWISE...UPSLOPE SNOW SHOWERS/ SQUALLS...COLD TEMPS... AND LOSS OF SOLAR INSOLATION SHOULD HELP THE EASTERN PORTION OF THE ADVISORIES PICK UP SNOW TOTALS THROUGH THE EVENING. THE SNOWS WILL TAPER OFF FROM WEST TO EAST LATER TONIGHT...ENDING LAST IN LOCATIONS NEAR THE VIRGINIA AND WEST VIRGINIA BORDERS TOWARD DAWN. BY THAT TIME READINGS WILL BE DOWN IN THE TEENS FOR MOST LOCATIONS WITH SOME SINGLE DIGITS POSSIBLE IN THE FAR NORTHWESTERN PARTS OF THE CWA. WINDS RUNNING IN THE 5 TO 10 MPH RANGE INTO EARLY FRIDAY MORNING WILL YIELD WIND CHILLS IN MANY SPOTS DOWN NEAR ZERO. THE QUICK EXIT OF THE WEATHER MAKER WILL RETURN SUNNY SKIES TO THE AREA ON FRIDAY... BUT CAA AND THE ARCTIC AIR IN PLACE WILL KEEP TEMPERATURES FROM GETTING ANY HIGHER THAN THE LOW TO MID 20S. THIS WILL SET THE STAGE FOR ANOTHER BITTERLY COLD NIGHT WITH READINGS FALLING INTO THE TEENS AGAIN ALONG WITH NOTICEABLE RIDGE AND VALLEY DIFFERENCES. AGAIN LEANED ON THE SOLID CONSSHORT OR BC VERSION FOR HOURLY TEMPS... DEWS...AND WINDS THROUGH 12Z FRIDAY WITH CONSALL AFTER THAT. AS FOR POPS...WENT HIGHER THAN GUIDANCE TONIGHT DUE TO IT NOT PICKING UP ON UPSLOPE SNOWS VERY WELL...DRY AFTER THAT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 250 PM EST THU JAN 2 2014 PRETTY GOOD AGREEMENT AMONGST THE MODELS FOR THE EXTENDED PERIOD. THE ECMWF MODEL IS A BIT MORE ROBUST WITH ITS QPF THAN THE GFS FOR THE SUNDAY NIGHT THROUGH MONDAY NIGHT WEATHER SYSTEM...AND THE WEATHER SYSTEM FOR THE END OF THE WEEK. HOWEVER...THE OVERALL LARGE SCALE WEATHER PATTERN...BOTH ALOFT AND AT THE SURFACE...IS SIMILAR IN BOTH MODELS. THAT BEING SAID...WENT MORE TOWARD THE ECMWF SOLUTION THIS TIME AROUND. TOOK DOWN SNOWFALL TOTALS SLIGHTLY...HOWEVER...AS THE MODELS HAVE MORE WESTERLY...AS OPPOSED TO NORTHWESTERLY...FLOW FORECAST...WHICH WOULD BE MUCH LESS FAVORABLE FOR UPSLOPE SNOW SHOWERS. THE DYNAMICS WITH THE SYSTEM TO BEGIN THE WEEK ARE STILL EXPECTED TO BE QUITE STRONG...WITH A WELL DEVELOPED AREA OF LOW PRESSURE MOVING OUT OF THE MID MISSISSIPPI VALLEY THROUGH THE OHIO VALLEY AND THEN INTO THE EASTERN GREAT LAKES REGION. A 50 TO 60KT LOW LEVEL JET WOULD BRING AMPLE GULF MOISTURE INTO THE REGION ALOFT TO AID IN ICE CRYSTAL AND THEREFORE SNOWFLAKE FORMATION SUNDAY NIGHT AND MONDAY. SNOWFALL TOTALS...DUE TO THE GOOD DYNAMICS...COULD STILL RANGE BETWEEN 2 AND 3 INCHES FOR MOST OF THE AREA DURING THE INITIAL EVENT. BITTERLY COLD ARCTIC AIR WILL SPILL INTO THE AREA TO BEING THE WEEK. THE COLDEST NIGHT OF THE UPCOMING WORK WEEK LOOKS TO BE MONDAY NIGHT...WHEN LOWS COULD CONCEIVABLE DROP TO ZERO OR BELOW ZERO FOR THE ENTIRE AREA. WITH THE MODEL SOUNDINGS DEPICTING 850 HPA TEMPERATURES IN THE MINUS 24 TO MINUS 30 RANGE...SUBZERO LOWS MONDAY NIGHT WOULD NOT BE ALL THAT SURPRISING. THE COLD AIR MASS WILL MODIFY ONLY SLIGHT TUESDAY WITH HIGHS PEAKING IN THE TEENS FOR MOST OF THE AREA...WITH HIGHS BARELY TOPPING OUT AROUND 10 DEGREES NORTH OF I-64. LOWS IN THE SINGLE DIGITS ARE LIKELY TUESDAY NIGHT...AS WINDS GO NEARLY CALM BENEATH PARTLY CLOUDY SKIES. HIGHS AND LOWS WEDNESDAY THROUGH THURSDAY WILL BE WELL BELOW AS WELL...AS THE COLD AIR MASS MAINTAINS ITS GRIP ON THE AREA. A SECOND WEATHER SYSTEM IS THEN PROGGED TO MOVE ACROSS THE TENNESSEE AND OHIO VALLEY REGIONS TO END THE WEEK...WITH MORE POTENTIAL FOR ACCUMULATING SNOW WEDNESDAY NIGHT INTO EARLY THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1206 AM EST FRI JAN 3 2014 CEILINGS WILL REMAIN IFR AND MVFR FOR MUCH OF THE REMAINDER OF THE EVENING ACROSS EASTERN KENTUCKY AS SNOW SHOWERS CONTINUE TO MOVE THROUGH THE AREA. CEILINGS AND VISIBILITY WILL IMPROVE TONIGHT FROM SOUTHWEST TO NORTHEAST AS THE SNOW MOVES OFF TO THE NORTHEAST BY 16Z FRIDAY. WINDS WILL REMAIN QUITE GUSTY UP TO 25 KNOTS FROM THE WEST AND WEST NORTHWEST AND WILL FINALLY DECREASE TO AROUND 10 KNOTS BY 12Z. VFR CONDITIONS WILL FINALLY RETURN FOR THE AREA BY 18Z. && .JKL WATCHES/WARNINGS/ADVISORIES... WINTER WEATHER ADVISORY UNTIL 2 AM EST FRIDAY FOR KYZ044-050>052- 058>060-079-083-084-104-106-108. WINTER WEATHER ADVISORY UNTIL 8 AM EST FRIDAY FOR KYZ088-118-120. WINTER WEATHER ADVISORY UNTIL 6 AM EST FRIDAY FOR KYZ068-069-080- 085>087-107-109>117-119. && $$ UPDATE...JJ SHORT TERM...GREIF LONG TERM...AR AVIATION...JJ
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
830 PM EST SAT JAN 4 2014 .SYNOPSIS... A WARM FRONT FROM THE WEST AND A DEVELOPING COASTAL LOW WILL BRING ANOTHER ROUND OF PRECIPITATION TO THE AREA LATE TONIGHT INTO SUNDAY. A STRONG COLD FRONT WILL CROSS THE REGION LATE SUNDAY NIGHT INTO MONDAY MORNING...FOLLOWED BY A VERY COLD ARCTIC AIRMASS FOR MONDAY AFTERNOON INTO MID-WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... SEASONABLE CHILL RMNS OVR THE RGN AS SFC HI PRES DRIFTS OFF THE CST. WNDS HAVE BECOME SSE OVR THE ENTIRE FA...GENERALLY AVGG 10 MPH OR LESS. CLOUDS CONTINUE TO SPREAD NORTHEAST ACROSS THE AREA. ALREADY REACHING THE RICHMOND AREA THIS EVENING. LOOKING SOUTHEAST WHERE THE CLOUDS HAVE BEEN ADVECTING UP FROM CAN SEE A SOLID DECK OF CLOUDS. THE RUC AND 18Z NAM SHOW THIS MOISTURE GENERALLY FROM 85H AND UNDER. THIS WILL HOLD TEMPS UP AS CONTINUED SE FLOW BRINGS IN STEADILY MILDER AIR. HAVE RAISED SOME TEMPERATURES A LITTLE AND WHERE THE CLOUDS HAVE ARRIVED HAVE NOT DROPPED TEMPERATURES AT ALL. THIS MEANS THE ONLY AREA NOW EXPECTING TO SETTLE BELOW FREEZING IS THE AREA FROM FVX NORTH THROUGH LOUISA. MDLS ARE DIVERGENT WRT POPS/PCPN...GFS SLOWER AND "DRIER" (W/ JUST LWRG CIGS)...WHILE THE NAM BRINGS IN AT LEAST LGT PCPN TO SCNTRL AND WRN PORTIONS OF THE FA AFT 06-09Z/05. TIME SECTIONS SHOW LITTLE OR NO MOISTURE REACHING NEAR THE MINUS 10 ISOTHERM SO WOULD NOT EXPECT MORE THEN VERY LIGHT PRECIPITATION OR DRIZZLE THROUGH THE NIGHT. ALSO HRRR SEEMS TO HAVE A GOOD HANDLE ON WHERE THE DRIZZLE AND LIGHT PRECIPITATION IS OCCURRING OVER SOUTH CAROLINA AND THAT HOLDS OFF ANY PRECIPITATION UNTIL AROUND SUNRISE IN THE SOUTHWEST. THERE IS LO CONFIDENCE RIGHT NOW FOR ANYTHING MORE THAN A TRACE QPF EVENT... NO HEADLINES ATTM...KEEPING MENTION IN HWO OF POSSIBLE FREEZING PRECIPITATION AROUND SUNRISE. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... MILDER/WARMER WX XPCD SUN INTO SUN NGT AHD OF APPROACHING LO PRES AND ASSOCIATED CDFNT FM THE W AND WK CSTL LO PRES TRACKING JUST OFF THE NC CST. VERY LIMITED DEPTH TO MOISTURE CONTG TO SPREAD OVR THE RGN DURG SUN...WHICH LIKELY MEANS THAT ANY PCPN WOULD BE LGT...AND MAY BE CONFINED TO AREAS INLAND/AWAY FM THE CST. THERE WILL RMN RESIDUAL CAD W OF I95 ON SUN WHILE THE WARMER AIR ARRIVES NWD ELSW. HI TEMPS FM THE L/M40S NW TO THE U50S/L60S IN SE VA/NE NC. THE WK CSTL LO TRACKS TO THE NE AND AWAY FM THE RGN SUN EVE...WHILE A STRONG CDFNT APPROACHES THE MTNS. THAT FNT MAKES ITS WAY ACRS THE MTNS AND ONTO THE PIEDMONT SUN NGT THROUGH MON MRNG...ACCOMPANIED BY A BAND/AREA OF RA (WHICH MAY MIX W/ SN ON WRN SIDE AS COLDER AIR BEGINS TO ARRIVE). THAT CDFNT CONTS TO PUSH ACRS THE FA DURG TUE...PUSHING OFF THE CST BY MID/LT MON AFTN...USHERING IN ANOTHER SHOT OF VERY COLD/ARCTIC AIR ON INCRSG NW WNDS. SCT-LIKELY SHRAS ACCOMPANY THE FNTL PASSAGE ON MON...WHICH MAY END AS ISOLD/SCT SHSN AS THE COLDER AIR CONTS IT MARCH EWD INTO THE FA (AND TEMPS FALL THROUGHOUT THE MIDDAY/AFTN HRS). LO TEMPS SUN NGT M/U30S FAR W...TO L50S SE. HI TEMPS MON (IN THE MRNG) FM ARND 40F W TO L50S SE. WHAT MAY END OF BEING THE COLDEST SHOT OF AIR INTO THE RGN SINCE FEB 1996 (OR JAN 1994) MON NGT THROUGH TUE. ISOLD/SCT SHSN ARE PSBL INVOF CST/OVR THE OCN (H85 TEMPS DROP TO BLO -18 DEGS C BY 12Z/07). OTRW...CLR TO PCDY...W/ LO TEMPS FM THE SINGLE DIGITS TO TEENS (MON NGT)...THEN HI TEMPS NO HIGHER THAN THE TEENS AND L20S ON TUE. WIND CHILLS MAY DROP TO OR BLO 0 DEGS F FOR A TIME FM LT MON INTO TUE (AS WNDS AVGG 15-25 MPH...W/ GUSTS TO 35-40 MPH PSBL). && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ARCTIC HIGH PRESSURE BUILDS OVERHEAD TUESDAY NIGHT WITH CURRENT FORECAST LOWS IN THE TEENS. THE HIGH REMAINS OVER THE AREA WEDNESDAY...WHICH WILL LIMIT MIXING AND RESULT IN HIGHS GENERALLY IN THE 30S AREAWIDE. DRY AND MAINLY CLEAR CONDITIONS ARE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY...ASIDE FROM ANY COLD-AIR CUMULUS STREAMERS OFF THE BAY. THE ARCTIC HIGH SLIDES OFF THE MID ATLANTIC COAST WEDNESDAY NIGHT AND THURSDAY. MEANWHILE...A SHORTWAVE DISTURBANCE APPROACHES FORM THE WEST THURSDAY...AND TRAVERSES ACROSS THE MID ATLANTIC REGION THURSDAY NIGHT INTO FRIDAY MORNING. SURFACE TEMPERATURES SHOULD RISE ABOVE 32 F ACROSS THE ENTIRE LOCAL AREA BY THE TIME ANY LIGHT PRECIP ARRIVES...SO ALL PRECIP IS STILL EXPECTED TO BE RAIN. HIGHS WILL BE NEAR SEASONAL AVERAGES THURSDAY AS CLOUD COVER AND LIMITED MIXING WILL PREVENT HIGHS FROM REACHING THEIR FULL POTENTIAL. ADDITIONAL SHORTWAVE ENERGY/MOISTURE IS EXPECTED TO CROSS THE AREA AT TIMES FROM FRIDAY THROUGH THE WEEKEND AS ANOTHER LONGWAVE TROUGH DIGS OVER THE CENTRAL U.S. && .AVIATION /01Z SUNDAY THROUGH THURSDAY/... LARGE AREA OF LOW CLOUDS ASSOCIATED WITH A TROF ALONG THE ATLANTIC COAST CONTINUES TO MAKE ITS WAY NORTH AND INTO CENTRAL VA. SFC OBS SHOW CLOUD CIGS AROUND 3-5K FT AT THE NORTHERN EDGE AND LOWERING TO MVFR 1000-1500 FT FARTHER SOUTH. TIMING OF CLOUDS OVER TAF SITES WILL BA CHALLENGING BUT EXPECT STRATOCU CIGS OVER CENTRAL VA EARLY TONIGHT...LOWERING TO MVFR COND AFTER MIDNIGHT...AND PSBL IFR CONDS AFTER SUNRISE. LIGHT SHOWERS OR DRIZZLE ASSOCIATED WITH THE COASTAL TROUGH COUPLED WITH A WEAK DAMMING SCENARIO WILL CREATE POSSIBLE IFR CEILINGS AND VIS SUN AFTN/EVENING. EXPECT A CHANCE OF SHOWERS ASSOCIATED WITH AN APPROACHING COLD FRONT MONDAY. GUSTY NW WINDS RETURN...ESP TO ERN PORTIONS MON NGT AND TUE MRNG. && .MARINE... SCA CONTINUES FOR SRN WATERS UNTIL 1 AM EDT FROM THE VA/NC BORDER TO CURRITUCK LIGHT. SEAS OF 5 TO 7 FT WILL PERSIST DURING THIS TIME BEFORE SUBSIDING BELOW 5 FT. A COASTAL LOW BEGINS TO TAKE SHAPE OFF THE FL COAST BY SUN MORNING...THEN DEEPENS AS IT TRACKS ALONG THE CAROLINA COAST TWD THE MID ATLANTIC WATERS DURING THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AS THE DAY PROGRESSES DUE TO A VERY STRONG ARCTIC COLD FRONT MOVING INTO THE TN/OH VALLEYS. THIS WILL CAUSE SE WINDS TO GRADUALLY INCREASE BY SUN AFTN. THE COASTAL LOW IS USHERING A WAA REGIME OVER THE WATERS DURING THIS TIME AND DO NOT ANTICIPATE MUCH SUCCESS IN MIXING DOWN STRONGER WINDS ALOFT. WILL KEEP WINDS CAPPED JUST BELOW SCA CRITERIA (15 KT BAY/RIVERS/SOUND...25 KT OCEAN) FROM SUN AFTN INTO SUN NIGHT. THE AFOREMENTIONED ARCTIC COLD FRONT IS EXPECTED TO RAPIDLY STRENGTHEN SUN NIGHT INTO MON MORNING AS IT MOVES FROM THE OH/TN VALLEYS INTO THE ERN GREAT LAKES REGION. THE VERY STRONG ARCTIC COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO CROSS THE WATERS MON MORNING THROUGH EARLY AFTN. S WINDS OF 20-25 KT MON MORNING WILL QUICKLY VEER TO THE NW BEHIND THE VIGOROUS FRONTAL PASSAGE AND INCREASE TO 25-30 KT. GUSTS UP TO 40 KT SHOULD BE ANTICIPATED OVER THE COASTAL WATERS IN ADDITION TO LOW-END GALE FORCE GUSTS POSSIBLE ON CHES BAY. WAVES/SEAS ARE ALSO EXPECTED TO RAPIDLY BUILD IN THE VICINITY OF THE COLD FRONT (CHES BAY WAVES 4-5 FT/COASTAL WATERS SEAS 5-8 FT). ALTHOUGH FORECAST MODELS HAVE BEEN FAIRLY CONSISTENT WITH THE TIMING OF THE FRONTAL PASSAGE ON MON...AM CONCERNED THAT A DEEP LONGWAVE TROUGH OVER THE CTRL U.S. WILL DIG A BIT DEEPER THAN EXPECTED. IF THIS OCCURS...THEN THE FRONTAL PASSAGE COULD BE SLOWED BY A FEW HOURS AND THUS DELAY THE ONSET OF STRONGER WINDS OVER THE WATERS MON MORNING. ON THE OTHER HAND...THE ARCTIC AIRMASS BEHIND THE COLD FRONT MAY PUSH THE FRONT ACROSS THE WATERS A FEW HOURS FASTER THAN ANTICIPATED. SINCE CURRENT FORECAST HAS WINDS INCREASING LATE IN THE THIRD PERIOD (OR JUST INSIDE 36 HOURS)...HAVE OPTED NOT TO ISSUE SCA OR GALE HEADLINES WITH THIS FORECAST ISSUANCE. VERY STRONG CAA MOVES OVER THE WATERS MON EVENING/OVERNIGHT AS A VERY COLD ARCTIC AIRMASS MOVES INTO THE MID ATLANTIC REGION BEHIND THE DEPARTING FRONT. THE SFC PRESSURE GRADIENT IS EXTREMELY TIGHT DUE TO THE VAST TEMPERATURE DIFFERENCES AHEAD OF AND BEHIND THE ARCTIC FRONT. TAKING THIS INTO CONSIDERATION...THERE MAY BE A PERIOD OF STRONGER WINDS (STILL GALE FORCE) WITH THE INITIAL COLD AIR PUSH WHICH FORECAST MODELS ARE NOT PICKING UP ON ATTM. HAVE MAINTAINED THE PREVIOUS FORECAST WIND STRENGTH THROUGH MON NIGHT... WHICH WAS ALREADY HIGHER THAN MODEL GUIDANCE. HOWEVER THIS MAY NEED TO BE INCREASED BY ANOTHER 5-10 KT ALL WATERS. BECAUSE WINDS BACK FROM NW TO W MON NIGHT...THE WIND SHIFT MAY BE ENOUGH TO HAMPER THE POTENTIAL FOR PROLONGED GALES VERSUS IF THE WINDS STAYED NW-N DURING THE COLD AIR SURGE. W WINDS REMAIN STRONG THROUGH TUE. THEN HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND THE TEMP/PRESSURE GRADIENT BEGINS TO RELAX...THUS ALLOWING WINDS TO SLOWLY DIMINISH DURING THE LATE AFTN/EVENING. SEAS SHOULD FOLLOW THE SAME TREND DURING THIS TIME BUT SHOULD NOT FALL BELOW 5 FT UNTIL CLOSER TO WED MORNING. HIGH PRESSURE CROSSES THE WATERS WED/THU WITH MORE BENIGN CONDITIONS EXPECTED. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST SUNDAY FOR ANZ658. && $$ SYNOPSIS...ALB/BMD/JDM NEAR TERM...ALB/JAB SHORT TERM...ALB LONG TERM...BMD AVIATION...DAP/JEF MARINE...BMD
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
710 PM EST SAT JAN 4 2014 .SYNOPSIS... A WARM FRONT FROM THE WEST AND A DEVELOPING COASTAL LOW WILL BRING ANOTHER ROUND OF PRECIPITATION TO THE AREA LATE TONIGHT INTO SUNDAY. A STRONG COLD FRONT WILL CROSS THE REGION LATE SUNDAY NIGHT INTO MONDAY MORNING...FOLLOWED BY A VERY COLD ARCTIC AIRMASS FOR MONDAY AFTERNOON INTO MID-WEEK. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... SEASONABLE CHILL RMNS OVR THE RGN AS SFC HI PRES DRIFTS OFF THE CST. WNDS HAVE BECOME SSE OVR THE ENTIRE FA...GENERALLY AVGG 10 MPH OR LESS. CLOUDS CONTINUE TO SPREAD NORTHEAST ACROSS THE AREA. ALREADY REACHING THE RICHMOND AREA THIS EVENING. LOOKING SOUTHEAST WHERE THE CLOUDS HAVE BEEN ADVECTING UP FROM CAN SEE A SOLID DECK OF CLOUDS. THE RUC AND 18Z NAM SHOW THIS MOISTURE GENERALLY FROM 85H AND UNDER. THIS WILL HOLD TEMPS UP AS CONTINUED SE FLOW BRINGS IN STEADILY MILDER AIR. HAVE RAISED SOME TEMPERATURES A LITTLE AND WHERE THE CLOUDS HAVE ARRIVED HAVE NOT DROPPED TEMPERATURES AT ALL. THIS MEANS THE ONLY AREA NOW EXPECTING TO SETTLE BELOW FREEZING IS THE AREA FROM FVX NORTH THROUGH LOUISA. MDLS ARE DIVERGENT WRT POPS/PCPN...GFS SLOWER AND "DRIER" (W/ JUST LWRG CIGS)...WHILE THE NAM BRINGS IN AT LEAST LGT PCPN TO SCNTRL AND WRN PORTIONS OF THE FA AFT 06-09Z/05. TIME SECTIONS SHOW LITTLE OR NO MOISTURE REACHING NEAR THE MINUS 10 ISOTHERM SO WOULD NOT EXPECT MORE THEN VERY LIGHT PRECIPITATION OR DRIZZLE THROUGH THE NIGHT. ALSO HRRR SEEMS TO HAVE A GOOD HANDLE ON WHERE THE DRIZZLE AND LIGHT PRECIPITATION IS OCCURRING OVER SOUTH CAROLINA AND THAT HOLDS OFF ANY PRECIPITATION UNTIL AROUND SUNRISE IN THE SOUTHWEST. THERE IS LO CONFIDENCE RIGHT NOW FOR ANYTHING MORE THAN A TRACE QPF EVENT... NO HEADLINES ATTM...KEEPING MENTION IN HWO OF POSSIBLE FREEZING PRECIPITATION AROUND SUNRISE. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/... MILDER/WARMER WX XPCD SUN INTO SUN NGT AHD OF APPROACHING LO PRES AND ASSOCIATED CDFNT FM THE W AND WK CSTL LO PRES TRACKING JUST OFF THE NC CST. VERY LIMITED DEPTH TO MOISTURE CONTG TO SPREAD OVR THE RGN DURG SUN...WHICH LIKELY MEANS THAT ANY PCPN WOULD BE LGT...AND MAY BE CONFINED TO AREAS INLAND/AWAY FM THE CST. THERE WILL RMN RESIDUAL CAD W OF I95 ON SUN WHILE THE WARMER AIR ARRIVES NWD ELSW. HI TEMPS FM THE L/M40S NW TO THE U50S/L60S IN SE VA/NE NC. THE WK CSTL LO TRACKS TO THE NE AND AWAY FM THE RGN SUN EVE...WHILE A STRONG CDFNT APPROACHES THE MTNS. THAT FNT MAKES ITS WAY ACRS THE MTNS AND ONTO THE PIEDMONT SUN NGT THROUGH MON MRNG...ACCOMPANIED BY A BAND/AREA OF RA (WHICH MAY MIX W/ SN ON WRN SIDE AS COLDER AIR BEGINS TO ARRIVE). THAT CDFNT CONTS TO PUSH ACRS THE FA DURG TUE...PUSHING OFF THE CST BY MID/LT MON AFTN...USHERING IN ANOTHER SHOT OF VERY COLD/ARCTIC AIR ON INCRSG NW WNDS. SCT-LIKELY SHRAS ACCOMPANY THE FNTL PASSAGE ON MON...WHICH MAY END AS ISOLD/SCT SHSN AS THE COLDER AIR CONTS IT MARCH EWD INTO THE FA (AND TEMPS FALL THROUGHOUT THE MIDDAY/AFTN HRS). LO TEMPS SUN NGT M/U30S FAR W...TO L50S SE. HI TEMPS MON (IN THE MRNG) FM ARND 40F W TO L50S SE. WHAT MAY END OF BEING THE COLDEST SHOT OF AIR INTO THE RGN SINCE FEB 1996 (OR JAN 1994) MON NGT THROUGH TUE. ISOLD/SCT SHSN ARE PSBL INVOF CST/OVR THE OCN (H85 TEMPS DROP TO BLO -18 DEGS C BY 12Z/07). OTRW...CLR TO PCDY...W/ LO TEMPS FM THE SINGLE DIGITS TO TEENS (MON NGT)...THEN HI TEMPS NO HIGHER THAN THE TEENS AND L20S ON TUE. WIND CHILLS MAY DROP TO OR BLO 0 DEGS F FOR A TIME FM LT MON INTO TUE (AS WNDS AVGG 15-25 MPH...W/ GUSTS TO 35-40 MPH PSBL). && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ARCTIC HIGH PRESSURE BUILDS OVERHEAD TUESDAY NIGHT WITH CURRENT FORECAST LOWS IN THE TEENS. THE HIGH REMAINS OVER THE AREA WEDNESDAY...WHICH WILL LIMIT MIXING AND RESULT IN HIGHS GENERALLY IN THE 30S AREAWIDE. DRY AND MAINLY CLEAR CONDITIONS ARE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY...ASIDE FROM ANY COLD-AIR CUMULUS STREAMERS OFF THE BAY. THE ARCTIC HIGH SLIDES OFF THE MID ATLANTIC COAST WEDNESDAY NIGHT AND THURSDAY. MEANWHILE...A SHORTWAVE DISTURBANCE APPROACHES FORM THE WEST THURSDAY...AND TRAVERSES ACROSS THE MID ATLANTIC REGION THURSDAY NIGHT INTO FRIDAY MORNING. SURFACE TEMPERATURES SHOULD RISE ABOVE 32 F ACROSS THE ENTIRE LOCAL AREA BY THE TIME ANY LIGHT PRECIP ARRIVES...SO ALL PRECIP IS STILL EXPECTED TO BE RAIN. HIGHS WILL BE NEAR SEASONAL AVERAGES THURSDAY AS CLOUD COVER AND LIMITED MIXING WILL PREVENT HIGHS FROM REACHING THEIR FULL POTENTIAL. ADDITIONAL SHORTWAVE ENERGY/MOISTURE IS EXPECTED TO CROSS THE AREA AT TIMES FROM FRIDAY THROUGH THE WEEKEND AS ANOTHER LONGWAVE TROUGH DIGS OVER THE CENTRAL U.S. && .AVIATION /00Z SUNDAY THROUGH THURSDAY/... VFR CONDS AT 18Z WITH MOSTLY CLEAR SKIES AND LIGHT SE-S WIND. SATELLITE IMAGE SHOWING LARGE AREA OF LOW CLOUDS FROM FLORIA TO THE CAROLINAS ASSOCIATED WITH A TROF ALONG THE ATLANTIC COAST. THE CLOUDS WILL GRADUALLY MOVE NORTH AS HIGH PRES OFF THE MID ATL COAST MOVES FARTHER EAST. SFC OBS SHOW CLOUD CIGS AROUND 4000-5000 FT AT THE NORTHERN EDGE AND LOWERING TO MVFR 1000-1500 FT FARTHER SOUTH. TIMING OF CLOUDS OVER TAF SITES A LITTLE DIFFICULT BUT EXPECT STRATOCU CIGS OVER CENTRL VA EARLY TONIGHT...LOWERING TO MVFR COND AFTER MIDNIGHT...AND PSBL IFR CONDS AFTER SUNRISE. A CHANCE OF SHOWERS IS IN THE FORECAST LATE SUNDAY THROUGH MONDAY. GUSTY NW WINDS RETURN...ESP TO ERN PORTIONS MON NGT AND TUE MRNG. && .MARINE... SCA CONTINUES FOR SRN WATERS UNTIL 1 AM EDT FROM THE VA/NC BORDER TO CURRITUCK LIGHT. SEAS OF 5 TO 7 FT WILL PERSIST DURING THIS TIME BEFORE SUBSIDING BELOW 5 FT. A COASTAL LOW BEGINS TO TAKE SHAPE OFF THE FL COAST BY SUN MORNING...THEN DEEPENS AS IT TRACKS ALONG THE CAROLINA COAST TWD THE MID ATLANTIC WATERS DURING THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AS THE DAY PROGRESSES DUE TO A VERY STRONG ARCTIC COLD FRONT MOVING INTO THE TN/OH VALLEYS. THIS WILL CAUSE SE WINDS TO GRADUALLY INCREASE BY SUN AFTN. THE COASTAL LOW IS USHERING A WAA REGIME OVER THE WATERS DURING THIS TIME AND DO NOT ANTICIPATE MUCH SUCCESS IN MIXING DOWN STRONGER WINDS ALOFT. WILL KEEP WINDS CAPPED JUST BELOW SCA CRITERIA (15 KT BAY/RIVERS/SOUND...25 KT OCEAN) FROM SUN AFTN INTO SUN NIGHT. THE AFOREMENTIONED ARCTIC COLD FRONT IS EXPECTED TO RAPIDLY STRENGTHEN SUN NIGHT INTO MON MORNING AS IT MOVES FROM THE OH/TN VALLEYS INTO THE ERN GREAT LAKES REGION. THE VERY STRONG ARCTIC COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO CROSS THE WATERS MON MORNING THROUGH EARLY AFTN. S WINDS OF 20-25 KT MON MORNING WILL QUICKLY VEER TO THE NW BEHIND THE VIGOROUS FRONTAL PASSAGE AND INCREASE TO 25-30 KT. GUSTS UP TO 40 KT SHOULD BE ANTICIPATED OVER THE COASTAL WATERS IN ADDITION TO LOW-END GALE FORCE GUSTS POSSIBLE ON CHES BAY. WAVES/SEAS ARE ALSO EXPECTED TO RAPIDLY BUILD IN THE VICINITY OF THE COLD FRONT (CHES BAY WAVES 4-5 FT/COASTAL WATERS SEAS 5-8 FT). ALTHOUGH FORECAST MODELS HAVE BEEN FAIRLY CONSISTENT WITH THE TIMING OF THE FRONTAL PASSAGE ON MON...AM CONCERNED THAT A DEEP LONGWAVE TROUGH OVER THE CTRL U.S. WILL DIG A BIT DEEPER THAN EXPECTED. IF THIS OCCURS...THEN THE FRONTAL PASSAGE COULD BE SLOWED BY A FEW HOURS AND THUS DELAY THE ONSET OF STRONGER WINDS OVER THE WATERS MON MORNING. ON THE OTHER HAND...THE ARCTIC AIRMASS BEHIND THE COLD FRONT MAY PUSH THE FRONT ACROSS THE WATERS A FEW HOURS FASTER THAN ANTICIPATED. SINCE CURRENT FORECAST HAS WINDS INCREASING LATE IN THE THIRD PERIOD (OR JUST INSIDE 36 HOURS)...HAVE OPTED NOT TO ISSUE SCA OR GALE HEADLINES WITH THIS FORECAST ISSUANCE. VERY STRONG CAA MOVES OVER THE WATERS MON EVENING/OVERNIGHT AS A VERY COLD ARCTIC AIRMASS MOVES INTO THE MID ATLANTIC REGION BEHIND THE DEPARTING FRONT. THE SFC PRESSURE GRADIENT IS EXTREMELY TIGHT DUE TO THE VAST TEMPERATURE DIFFERENCES AHEAD OF AND BEHIND THE ARCTIC FRONT. TAKING THIS INTO CONSIDERATION...THERE MAY BE A PERIOD OF STRONGER WINDS (STILL GALE FORCE) WITH THE INITIAL COLD AIR PUSH WHICH FORECAST MODELS ARE NOT PICKING UP ON ATTM. HAVE MAINTAINED THE PREVIOUS FORECAST WIND STRENGTH THROUGH MON NIGHT... WHICH WAS ALREADY HIGHER THAN MODEL GUIDANCE. HOWEVER THIS MAY NEED TO BE INCREASED BY ANOTHER 5-10 KT ALL WATERS. BECAUSE WINDS BACK FROM NW TO W MON NIGHT...THE WIND SHIFT MAY BE ENOUGH TO HAMPER THE POTENTIAL FOR PROLONGED GALES VERSUS IF THE WINDS STAYED NW-N DURING THE COLD AIR SURGE. W WINDS REMAIN STRONG THROUGH TUE. THEN HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND THE TEMP/PRESSURE GRADIENT BEGINS TO RELAX...THUS ALLOWING WINDS TO SLOWLY DIMINISH DURING THE LATE AFTN/EVENING. SEAS SHOULD FOLLOW THE SAME TREND DURING THIS TIME BUT SHOULD NOT FALL BELOW 5 FT UNTIL CLOSER TO WED MORNING. HIGH PRESSURE CROSSES THE WATERS WED/THU WITH MORE BENIGN CONDITIONS EXPECTED. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 1 AM EST SUNDAY FOR ANZ658. && $$ SYNOPSIS...ALB/BMD/JDM NEAR TERM...ALB/JAB SHORT TERM...ALB LONG TERM...BMD AVIATION...JEF MARINE...BMD
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1254 PM EST FRI JAN 3 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 328 AM EST FRI JAN 3 2014 THE BIG WEATHER STORY THROUGH THE NEXT FEW DAYS WILL BE THE ARRIVAL OF AN ARCTIC BLAST SATURDAY NIGHT AND THE CORE OF THE COLDEST AIR COMING ON MONDAY AND TUESDAY. MEANTIME...WE/LL SEE SOME SUNSHINE TODAY BEFORE LAKE CLOUDS DEVELOP. HOWEVER THE WIND IS GOING TO PICK UP AND WHEN COMBINED WITH TEMPS IN THE TEENS WILL PRODUCE WIND CHILLS IN THE 10 TO 15 BELOW RANGE EARLY TODAY. THE COLDEST AIR WILL ARRIVE MONDAY AND TUESDAY. TEMPERATURES WILL STRUGGLE TO RISE ABOVE 0. WIND CHILLS 20 TO 30 BELOW SEEM LIKELY MONDAY AND TUESDAY. WARMER AIR WILL ARRIVE BY THE END OF NEXT WEEK. && .UPDATE... ISSUED AT 1104 AM EST FRI JAN 3 2014 DOMINANT LAKE SNOW BAND IS CURRENTLY MOVING ONSHORE NEAR MUSKEGON...BUT BOTH RADAR AND SURFACE OBSERVATIONS SUGGEST THAT THE INTENSITY IS WEAK. REGARDING INCREASING WIND LATER TODAY...LATEST HRRR MODEL GUIDANCE SUGGESTS THAT EXPOSED LAKESHORE AREAS TO THE NORTH /I.E... THE SABLE POINTS/ COULD SEE WIND ADVISORY CRITERIA BEING MET AT THE IMMEDIATE LAKESHORE. GIVEN A WIND DIRECTION GENERALLY FROM THE SOUTH...DO NOT EXPECT MUCH INLAND EXTENT TO THE STRONGEST WINDS SO DO NOT PLAN TO ISSUE A WIND ADVISORY. AFTER DISCUSSION WITH THE DETROIT AND NORTHERN INDIANA OFFICES... WILL BE ISSUING A WINTER STORM WATCH OVER SOUTHEAST ZONES FOR SNOW SATURDAY NIGHT THROUGH SUNDAY. THERE IS MODERATE CONFIDENCE REGARDING ACCUMULATIONS. THE MAIN IMPACTS MAY BE TRAVEL RELATED AS ALREADY ICY CONDITIONS HAVE BEEN REPORTED IN THE AREA. A BIT MORE CERTAIN IS DANGEROUS WIND CHILLS MONDAY AND TUESDAY. THEREFORE PLAN TO ISSUE A SEPARATE WATCH TO COVER THIS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 328 AM EST FRI JAN 3 2014 FORECAST CONCERNS DEAL WITH WIND CHILLS THIS MORNING AND THEN SNOW POTENTIAL SATURDAY AND SUNDAY. WINDS WILL PICK UP THIS AFTERNOON AS THE CLIPPER DRAGGING THE ARCTIC FRONT APPROACHES. IN FACT...WINDS ALONG THE COAST MAY APPROACH ADVISORY CRITERIA BUT FOR THE MOST PART SHOULD FALL JUST SHY. WIND CHILLS THIS MORNING SHOULD BE IN THE 10 TO 15 BELOW RANGE FOR A FEW HOURS BEFORE CLIMBING THIS AFTERNOON. SOME SNOW SHOWERS WILL ALSO DEVELOP NORTH OF MUSKEGON AND WEST OF US-131 AS SW FLOW DEVELOPS BUT ACCUMS SHOULD BE LESS THAN AN INCH AS MOISTURE IS A LIMITING FACTOR ALONG WITH UPPER SHORT WAVE RIDGING. SATURDAY WILL BE THE WARMEST DAY AS TEMPS MAKE A RUN AT 30 IN SW FLOW AHEAD OF THE FRONT. HOWEVER...BREEZY CONDITIONS WILL MAKE IT FEEL MUCH COLDER. THE ARCTIC FRONT WILL MOVE THROUGH THE CWA SATURDAY AFTERNOON. LIGHT SNOW WILL ACCOMPANY THE FRONT. ACCUMS IN THE 1 TO 3 INCH RANGE SEEM POSSIBLE. THERE IS SOME OMEGA IN THE DGZ AS IT LOWERS THROUGH THE PERIOD FROM SATURDAY NIGHT THROUGH SUNDAY. TEMPS WON/T MOVE MUCH SUNDAY AS STRONG COLD AIR ADVECTION WILL BE UNDERWAY. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 328 AM EST FRI JAN 3 2014 THE DANGEROUSLY LOW WIND CHILLS FOR MONDAY THROUGH TUESDAY MORNING CONTINUE TO BE THE WEATHER HIGHLIGHT IN THE LONG TERM. WIND CHILL READINGS ON MONDAY AND MONDAY NIGHT AROUND -25 OR COLDER WILL LIKELY NECESSITATE WIND CHILL WARNINGS FOR THE FIRST DAY BACK TO SCHOOL. SINCE WE WILL BE COLD ADVECTING LATE SUNDAY NIGHT AND ALL DAY MONDAY... THE HIGH TEMP FOR MONDAY 1/6 WILL PROBABLY BE THE MIDNIGHT READING. TEMPS ON MONDAY AFTERNOON MAY ACTUALLY FALL BELOW ZERO. IF IT TURNS OUT THAT THE HIGH ON MONDAY IS ONLY AROUND ZERO... THIS COULD BE IN THE TOP TEN COLDEST HIGH TEMPS AT LEAST AT GRR. LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW ALONG AND WEST OF HIGHWAY 131 MONDAY AND TUESDAY WILL BE ADDITIONAL HAZARDS EARLY NEXT WEEK THAT MAY PRODUCE TRAVEL IMPACTS. THE VERY COLD TEMPS AND SNOW WILL MAKE ROADS ICY AND CHEMICALS WILL PROBABLY BE INEFFECTIVE. TOTAL LAKE EFFECT SNOW ACCUMULATIONS SHOULD BE RELATIVELY LIGHT GIVEN THAT A DGZ WILL NOT BE PRESENT DUE TO THE VERY COLD AIR MASS. THAT MAY BEGIN TO CHANGE BY TUESDAY AFTERNOON AS SLIGHT WARMING ALLOWS THE DGZ TO RETURN TO THE CLOUD LAYER. ALTHOUGH THE CORE OF THE COLDEST AIR LIFTS OUT ON TUESDAY... THE SNOW THREAT CONTINUES INTO WEDNESDAY AND THURSDAY AS ANOTHER H5 TROUGH DIGS WEST OF MI AND MAY INDUCE WARM ADVECTION SNOWS. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1254 PM EST FRI JAN 3 2014 VISIBILITIES BELOW A MILE AND CEILINGS UNDER 1000 FEET AT MUSKEGON DUE TO A SNOWBAND... WILL IMPROVE TO VFR LEVELS OVER THE NEXT COUPLE OF HOURS. ELSEWHERE... VFR CONDITIONS EXPECTED INTO SATURDAY. GUSTY WINDS OUT OF THE SOUTH WILL INGREASE THIS AFTERNOON AND TONIGHT WITH STEADY WINDS BY MORNING OF 20 KNOTS AND GUSTS TO AROUND 35 KNOTS POSSIBLE. WINDS NEAR THE LAKESHORE TONIGHT COULD GUST AS HIGH AS 40 KNOTS AFTER 00Z. && .MARINE... ISSUED AT 856 PM EST THU JAN 2 2014 UPGRADED THE GALE WATCH TO A WARNING. CONFIDENCE IS PRETTY HIGH THAT WINDS WILL REALLY PICK UP FRIDAY AFTERNOON FROM THE SOUTHWEST AND REACH GALES LATE IN THE DAY. && .HYDROLOGY... ISSUED AT 236 PM EST THU JAN 2 2014 A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED. RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ844>849. GALE WARNING UNTIL 1 PM EST SATURDAY FOR LMZ844>849. && $$ UPDATE...TJT SYNOPSIS...93 SHORT TERM...93 LONG TERM...MEADE AVIATION...63 HYDROLOGY...EBW MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1134 AM EST FRI JAN 3 2014 LATEST UPDATE... UPDATE .SYNOPSIS... ISSUED AT 328 AM EST FRI JAN 3 2014 THE BIG WEATHER STORY THROUGH THE NEXT FEW DAYS WILL BE THE ARRIVAL OF AN ARCTIC BLAST SATURDAY NIGHT AND THE CORE OF THE COLDEST AIR COMING ON MONDAY AND TUESDAY. MEANTIME...WE/LL SEE SOME SUNSHINE TODAY BEFORE LAKE CLOUDS DEVELOP. HOWEVER THE WIND IS GOING TO PICK UP AND WHEN COMBINED WITH TEMPS IN THE TEENS WILL PRODUCE WIND CHILLS IN THE 10 TO 15 BELOW RANGE EARLY TODAY. THE COLDEST AIR WILL ARRIVE MONDAY AND TUESDAY. TEMPERATURES WILL STRUGGLE TO RISE ABOVE 0. WIND CHILLS 20 TO 30 BELOW SEEM LIKELY MONDAY AND TUESDAY. WARMER AIR WILL ARRIVE BY THE END OF NEXT WEEK. && .UPDATE... ISSUED AT 1104 AM EST FRI JAN 3 2014 DOMINANT LAKE SNOW BAND IS CURRENTLY MOVING ONSHORE NEAR MUSKEGON...BUT BOTH RADAR AND SURFACE OBSERVATIONS SUGGEST THAT THE INTENSITY IS WEAK. REGARDING INCREASING WIND LATER TODAY...LATEST HRRR MODEL GUIDANCE SUGGESTS THAT EXPOSED LAKESHORE AREAS TO THE NORTH /I.E... THE SABLE POINTS/ COULD SEE WIND ADVISORY CRITERIA BEING MET AT THE IMMEDIATE LAKESHORE. GIVEN A WIND DIRECTION GENERALLY FROM THE SOUTH...DO NOT EXPECT MUCH INLAND EXTENT TO THE STRONGEST WINDS SO DO NOT PLAN TO ISSUE A WIND ADVISORY. AFTER DISCUSSION WITH THE DETROIT AND NORTHERN INDIANA OFFICES... WILL BE ISSUING A WINTER STORM WATCH OVER SOUTHEAST ZONES FOR SNOW SATURDAY NIGHT THROUGH SUNDAY. THERE IS MODERATE CONFIDENCE REGARDING ACCUMULATIONS. THE MAIN IMPACTS MAY BE TRAVEL RELATED AS ALREADY ICY CONDITIONS HAVE BEEN REPORTED IN THE AREA. A BIT MORE CERTAIN IS DANGEROUS WIND CHILLS MONDAY AND TUESDAY. THEREFORE PLAN TO ISSUE A SEPARATE WATCH TO COVER THIS. && .SHORT TERM...(TODAY THROUGH SUNDAY) ISSUED AT 328 AM EST FRI JAN 3 2014 FORECAST CONCERNS DEAL WITH WIND CHILLS THIS MORNING AND THEN SNOW POTENTIAL SATURDAY AND SUNDAY. WINDS WILL PICK UP THIS AFTERNOON AS THE CLIPPER DRAGGING THE ARCTIC FRONT APPROACHES. IN FACT...WINDS ALONG THE COAST MAY APPROACH ADVISORY CRITERIA BUT FOR THE MOST PART SHOULD FALL JUST SHY. WIND CHILLS THIS MORNING SHOULD BE IN THE 10 TO 15 BELOW RANGE FOR A FEW HOURS BEFORE CLIMBING THIS AFTERNOON. SOME SNOW SHOWERS WILL ALSO DEVELOP NORTH OF MUSKEGON AND WEST OF US-131 AS SW FLOW DEVELOPS BUT ACCUMS SHOULD BE LESS THAN AN INCH AS MOISTURE IS A LIMITING FACTOR ALONG WITH UPPER SHORT WAVE RIDGING. SATURDAY WILL BE THE WARMEST DAY AS TEMPS MAKE A RUN AT 30 IN SW FLOW AHEAD OF THE FRONT. HOWEVER...BREEZY CONDITIONS WILL MAKE IT FEEL MUCH COLDER. THE ARCTIC FRONT WILL MOVE THROUGH THE CWA SATURDAY AFTERNOON. LIGHT SNOW WILL ACCOMPANY THE FRONT. ACCUMS IN THE 1 TO 3 INCH RANGE SEEM POSSIBLE. THERE IS SOME OMEGA IN THE DGZ AS IT LOWERS THROUGH THE PERIOD FROM SATURDAY NIGHT THROUGH SUNDAY. TEMPS WON/T MOVE MUCH SUNDAY AS STRONG COLD AIR ADVECTION WILL BE UNDERWAY. .LONG TERM...(SUNDAY NIGHT THROUGH THURSDAY) ISSUED AT 328 AM EST FRI JAN 3 2014 THE DANGEROUSLY LOW WIND CHILLS FOR MONDAY THROUGH TUESDAY MORNING CONTINUE TO BE THE WEATHER HIGHLIGHT IN THE LONG TERM. WIND CHILL READINGS ON MONDAY AND MONDAY NIGHT AROUND -25 OR COLDER WILL LIKELY NECESSITATE WIND CHILL WARNINGS FOR THE FIRST DAY BACK TO SCHOOL. SINCE WE WILL BE COLD ADVECTING LATE SUNDAY NIGHT AND ALL DAY MONDAY... THE HIGH TEMP FOR MONDAY 1/6 WILL PROBABLY BE THE MIDNIGHT READING. TEMPS ON MONDAY AFTERNOON MAY ACTUALLY FALL BELOW ZERO. IF IT TURNS OUT THAT THE HIGH ON MONDAY IS ONLY AROUND ZERO... THIS COULD BE IN THE TOP TEN COLDEST HIGH TEMPS AT LEAST AT GRR. LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW ALONG AND WEST OF HIGHWAY 131 MONDAY AND TUESDAY WILL BE ADDITIONAL HAZARDS EARLY NEXT WEEK THAT MAY PRODUCE TRAVEL IMPACTS. THE VERY COLD TEMPS AND SNOW WILL MAKE ROADS ICY AND CHEMICALS WILL PROBABLY BE INEFFECTIVE. TOTAL LAKE EFFECT SNOW ACCUMULATIONS SHOULD BE RELATIVELY LIGHT GIVEN THAT A DGZ WILL NOT BE PRESENT DUE TO THE VERY COLD AIR MASS. THAT MAY BEGIN TO CHANGE BY TUESDAY AFTERNOON AS SLIGHT WARMING ALLOWS THE DGZ TO RETURN TO THE CLOUD LAYER. ALTHOUGH THE CORE OF THE COLDEST AIR LIFTS OUT ON TUESDAY... THE SNOW THREAT CONTINUES INTO WEDNESDAY AND THURSDAY AS ANOTHER H5 TROUGH DIGS WEST OF MI AND MAY INDUCE WARM ADVECTION SNOWS. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 658 AM EST FRI JAN 3 2014 WITH THE EXCEPTION OF MKG... VFR LIKELY TODAY AND TONIGHT WITH INCREASING WINDS FROM THE SOUTH. WINDS THIS AFTERNOON WILL BEGIN GUSTING TO 20-25 KNOTS BUT THE STRONGEST WINDS WILL BE TONIGHT WHEN GUSTS TO 25-30 KNOTS ARE EXPECTED. AT MKG... A BAND OF DISSIPATING LAKE EFFECT SNOW WILL COME ONSHORE AROUND MID MORNING BRINGING MVFR VSBYS AND CIGS... AND POSSIBLY A PERIOD OF IFR. THE SNOW SHOWERS SHOULD DISSIPATE COMPLETELY BY MID AFTERNOON. WINDS AT THE LAKESHORE TONIGHT COULD GUST AS HIGH AS 40 KTS AT TIMES AFTER 00Z. && .MARINE... ISSUED AT 856 PM EST THU JAN 2 2014 UPGRADED THE GALE WATCH TO A WARNING. CONFIDENCE IS PRETTY HIGH THAT WINDS WILL REALLY PICK UP FRIDAY AFTERNOON FROM THE SOUTHWEST AND REACH GALES LATE IN THE DAY. && .HYDROLOGY... ISSUED AT 236 PM EST THU JAN 2 2014 A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED. RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR LMZ844>849. GALE WARNING UNTIL 1 PM EST SATURDAY FOR LMZ844>849. && $$ UPDATE...TJT SYNOPSIS...93 SHORT TERM...93 LONG TERM...MEADE AVIATION...MEADE HYDROLOGY...EBW MARINE...93
AREA FORECAST DISCUSSION
NWS GRAND RAPIDS MI
1124 PM EST THU JAN 2 2014 LATEST UPDATE... AVIATION .SYNOPSIS... ISSUED AT 236 PM EST THU JAN 2 2014 THE BIG WEATHER STORY IS THE COLD OUTBREAK EXPECTED EARLY NEXT WEEK. HIGHS IN THE SINGLE DIGITS AND LOWS IN THE 0 TO 10 BELOW RANGE ARE EXPECTED. WIND CHILLS COULD DROP AS LOW AS 25 BELOW ON MONDAY AND TUESDAY. WIND GUSTS ARE FORECAST TO BE AROUND 20 TO 30 MPH. ANOTHER VERY COLD NIGHT IS IN STORE TONIGHT WITH LOWS IN THE 0 TO 5 BELOW RANGE. SOME LIGHT SNOW NEAR THE LAKESHORE IS POSSIBLE FRIDAY. WIDESPREAD HEAVIER SNOW WILL MOVE IN SUNDAY AND SUNDAY NIGHT. SIGNIFICANT ACCUMULATIONS APPEAR LIKELY AT THIS TIME...ESPECIALLY SOUTH AND EAST OF GRAND RAPIDS. TEMPERATURES WILL MODERATE CONSIDERABLY ON SATURDAY BEFORE THE ARCTIC AIR PLUNGES BACK IN. HIGHS ON SATURDAY WILL BE NEAR 30 DEGREES. && .SHORT TERM...(THIS EVENING THROUGH SATURDAY NIGHT) ISSUED AT 303 PM EST THU JAN 2 2014 MAIN CHALLENGE IN THE VERY SHORT TERM IS ASSESSING SNOW POTENTIAL NEAR THE LAKESHORE...PARTICULARLY AROUND THE SABLE POINTS OF MASON AND OCEANA COUNTIES. A DOMINANT LAKE SNOW BAND NEAR THE WESTERN LAKE MICHIGAN SHORELINE THIS MORNING IS SLOWLY DRIFTING EAST. THE LAST SEVERAL HRRR MODEL RUNS...AS WELL AS THE NAM...APPEAR TO BE PLACING OR MOVING THIS FEATURE TOO FAR EAST TOWARDS THE POINTS. IT IS LOOKING MORE LIKELY THAT WE WILL CLEAR OUT OVER INLAND ZONES TONIGHT...ALLOWING FOR VERY COLD INLAND TEMPERATURES FRIDAY MORNING AND A LAND BREEZE THAT HAS A GOOD CHANCE OF KEEPING THE SNOW BAND OFFSHORE. DISCUSSED THIS WITH THE GAYLORD OFFICE AND WE BOTH CONCUR THAT THIS IS THE MOST LIKELY SCENARIO AT THIS POINT. HAVE THEREFORE TRIMMED POPS AND ACCUMULATIONS EXCEPT FOR THE IMMEDIATE COAST. STILL LOOKING FAVORABLE FOR LIGHT LAKE ENHANCED SNOW FRIDAY AHEAD OF THE NEXT CLIPPER. DID NOT CHANGE THE INHERITED FORECAST SIGNIFICANTLY. FROM FRIDAY NIGHT THROUGH SATURDAY POPS INCREASE FROM NORTHWEST TO SOUTHEAST AHEAD OF THE CLIPPER AND ASSOCIATED COLD FRONT WHICH SHOULD BE ENTERING THE FORECAST AREA BY SATURDAY EVENING. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 328 PM EST THU JAN 2 2014 THE MEDIUM RANGE MODELS CONTINUE IN GOOD AGREEMENT ON THE LARGE SCALE FLOW WITH MINOR DIFFERENCES IN THE SMALLER SCALE FEATURES. CONFIDENCE IS HIGH DUE TO CONTINUITY IN TIME AND SPACE. WIND CHILL VALUES AND SNOWFALL ARE THE CHALLENGES WITH THIS FORECAST PACKAGE. TEMPERATURES WILL FALL TO 0-5 DEGREES SUNDAY NIGHT AND ON MONDAY THE HIGHS WILL BE AROUND 5 DEGREES ABOVE ZERO. THE LOWS MONDAY NIGHT WILL BE BELOW ZERO. VALUES THIS LOW HAVE NOT BEEN SEEN IN THIS AREA SINCE FEB 2007. THE TEMPERATURES WILL BEGIN TO RECOVER WEDNESDAY. ALONG WITH THE COLD AIR... STRONG GUSTY WINDS OUT OF THE WEST AND NORTHWEST WILL PRODUCE LOW WIND CHILL VALUES. THE COLDEST WIND CHILLS... BETWEEN 20 AND 30 DEGREES BELOW ZERO ARE POSSIBLE MONDAY EVENING INTO TUESDAY MORNING. A WIND CHILL ADVISORY AND MAYBE A WIND CHILL WARNING WILL BE NEEDED MONDAY AFTERNOON THROUGH TUESDAY AFTERNOON. THIS ALSO SEEMS TO BE A SNOWY PERIOD OF TIME. AN UPPER LOW WILL DROP SOUTH FROM NEAR THE POLE AND MOVE EAST ACROSS SOUTHERN CANADA THROUGH THE LONG TERM. THIS AND SHORTWAVES MOVING THROUGH THE FLOW AROUND THE LOW WILL BRING THE COLD AIR... CYCLONIC FLOW AND SNOW. A FEW SHORTWAVES SHOULD PASS CLOSE ENOUGH TO THE AREA TO RESULT IN SNOW SATURDAY NIGHT THROUGH SUNDAY NIGHT. THE UPPER LOW WILL HELP TO BUMP UP THE LAKE EFFECT SNOW MONDAY INTO WEDNESDAY AS THE SYSTEM PULLS AWAY. WITH THE COLD TEMPERATURES... THE LAKE EFFECT SNOW IS EXPECTED TO BE IN THE FORM OF SMALL ICE CRYSTALS. THEREFORE THE SNOW WILL NOT STACK UP... BUT THE STRONG WINDS WILL BLOW THIS SNOW AROUND. THIS WILL RESULT IN GREATLY REDUCED VISIBILITIES. THIS WILL ESPECIALLY BE TRUE NEAR LAKE MICHIGAN. A MORE ZONAL FLOW PATTERN WILL ENSUE WEDNESDAY... AS A LOW PRESSURE SYSTEM BEGINS MOVING BY TO THE SOUTH OF THE REGION. THIS HAS THE POTENTIAL FOR ADDITIONAL SNOWFALL. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1121 PM EST THU JAN 2 2014 CLEARING SKIES CONTINUE FOR MUCH OF SOUTHWEST LOWER MICHIGAN. THIS WILL ALLOW FOR MAINLY VFR WEATHER AT THE TAF SITES FOR MUCH OF THE NIGHT. ALONG THE COAST NEAR KMKG CONDITIONS WILL LOWER TO MVFR/IFR FRIDAY AM AS A BAND OF SNOW PUSHES IN FROM THE WEST. WINDS WILL INCREASE AS WE GO THROUGH FRIDAY. STRONGEST VALUES WILL OCCUR ON THE LAKESHORE WHERE VALUES WILL EASILY TOP 25 KNOTS DURING THE AFTERNOON. && .MARINE... ISSUED AT 856 PM EST THU JAN 2 2014 UPGRADED THE GALE WATCH TO A WARNING. CONFIDENCE IS PRETTY HIGH THAT WINDS WILL REALLY PICK UP FRIDAY AFTERNOON FROM THE SOUTHWEST AND REACH GALES LATE IN THE DAY. && .HYDROLOGY... ISSUED AT 236 PM EST THU JAN 2 2014 A FLOOD ADVISORY IS IN EFFECT FOR THE FLAT RIVER AT SMYRNA. A SUSPECTED ICE JAM UPSTREAM IS CAUSING A SHARP RISE AT THE SMYRNA RIVER GAUGE. THE ICE JAM ON THE MUSKEGON RIVER THAT HAS IMPACTED EVART SEEMS TO HAVE STABILIZED. THE MUSKEGON RIVER AT EVART IS NOW ON A GRADUAL DECLINE. THE FLOOD ADVISORIES FOR THE MUSKEGON RIVER AT EVART AND THE PERE MARQUETTE RIVER AT SCOTTVILLE HAVE BEEN CANCELED. RIVERS WILL CONTINUE GAINING ICE COVERAGE AND THICKNESS FOR THE FORESEEABLE FUTURE. THOSE RIVERS THAT ICE OVER COMPLETELY WILL HAVE A MINIMAL ICE JAM THREAT. RIVERS WITH JAGGED ICE BUILDUP ARE IN DANGER OF EXPERIENCING JAMMING AND RAPID FLUCTUATIONS. WIDESPREAD HEAVIER SNOW IS LIKELY SUNDAY AND SUNDAY NIGHT...FOLLOWED IMMEDIATELY BY A BLAST OF EXTREMELY COLD AIR. HOPEFULLY RIVER LEVELS WILL LOCK IN SOMEWHAT WITH THE COLD AIR IN PLACE. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...NONE. LM...SMALL CRAFT ADVISORY UNTIL 1 PM EST FRIDAY FOR LMZ844>849. GALE WARNING FROM 1 PM FRIDAY TO 1 PM EST SATURDAY FOR LMZ844>849. && $$ SYNOPSIS...EBW SHORT TERM...TJT LONG TERM...63 AVIATION...MJS HYDROLOGY...EBW MARINE...93
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
328 PM CST FRI JAN 3 2014 .SHORT TERM...(THIS EVENING THROUGH SATURDAY) ISSUED AT 328 PM CST FRI JAN 3 2014 BEFORE THE MAIN SURGE OF EXTREMELY COLD AIR ARRIVES OVER THE WEEKEND...A STRONG STORM SYSTEM AHEAD OF THIS AIR MASS HAS MODIFIED ENOUGH TO PRODUCE A PERIOD OF FREEZING RAIN AND SLEET THIS EVENING AS IT MOVES FROM THE WESTERN DAKOTAS...EASTWARD ACROSS THE UPPER MIDWEST OVERNIGHT. REGIONAL RADAR ALSO ALREADY INDICATED A LARGE AREA OF PRECIPITATION DEVELOPING ACROSS CENTRAL ND...SOUTHWARD INTO CENTRAL SD. ABV THE SFC...TEMPS HAVE WARMED SIGNIFICANTLY...WITH 85H TEMPS NEAR +6C IN WC MN TO NEAR 0C IN EC MN. HOWEVER...IN THE LOWEST 1-2K...TEMPS WERE NEAR -10C IN EC MN...TO -4C IN WC MN. THE DEPTH OF THE COLDER TEMPS IN EASTERN MN WILL ALLOW FOR MAINLY SLEET AND SOME -SN. HOWEVER...FURTHER TO THE WEST...THE PRECIPITATION HAS A BETTER CHC OF HOLDING AS LIQUID AND NOT REFREEZING IN THE FORM OF SLEET. THEREFORE...A BETTER CHC OF FREEZING RAIN IS EXPECTED IN WC MN DURING THE EVENING HRS BEFORE THE ARCTIC FRONT ARRIVES AFT MIDNIGHT. DEPENDING UPON HOW MUCH FURTHER THE WARMER AIR ADVECTS TO THE EAST...WILL DEPEND IF EASTERN MN GETS MORE FREEZING RAIN OR SLEET. WC WI WILL LIKELY REMAIN SNOW OR A MIXTURE OF SLEET AND SNOW. QPF AMTS REMAIN FAIRLY LIGHT...BUT EVEN A FEW HUNDREDTHS OF AN INCH OF FREEZING RAIN CAN CAUSE HAZARDOUS ROADS IF NOT TREATED. A WINTER WX ADV WAS ISSUED BASED ON THE FREEZING PRECIPITATION AND THEN BLOWING AND DRIFTING SNOW AFTER MIDNIGHT. ONLY SMALL CHGS IN THE FORECAST ON SATURDAY AS TEMPS WILL CONTINUE TO FALL THROUGHOUT THE DAY. WIND CHILL VALUES BY LATE SATURDAY AFTERNOON WILL RANGE FROM -30 TO -35F IN CENTRAL/WC MN...TO AROUND -15 IN WC WI. .LONG TERM...(SATURDAY NIGHT THROUGH FRIDAY) ISSUED AT 328 PM CST FRI JAN 3 2014 THE WORST ARCTIC OUTBREAK SO FAR THIS COLD SEASON WILL BE UNDERWAY AT THE START OF THE LONG TERM. DETERMINISTIC SOLUTIONS CONTINUE TO DRIVE A POLAR VORTEX... CURRENTLY OVER THE YUKON... TO NEAR KDLH BY SUNDAY EVENING... WITH 1000-500MB THICKNESS VALUES BELOW 486 (DAM). VERTICAL PROFILES BETWEEN THE SURFACE AND 850MB SHOW TEMPERATURES IN THE -30 TO -35 DEG C RANGE ACROSS THE CWA SUNDAY NIGHT AND MONDAY. THIS UPCOMING COLD IS QUITE SIMILAR PATTERN-WISE TO THAT IN EARLY JANUARY 1982. A CHECK ON WEATHER MAPS DURING THAT COLD OUTBREAK SHOWED THE UPPER LOW BOTTOMING OUT ACROSS THE UPPER GREAT LAKES ALONG WITH THE SURFACE HIGH STAYING WELL WEST AND SOUTH OF THE FA. THIS RESULTS IN THE LIKELYHOOD OF SOME CLOUDINESS DUE TO PROXIMITY OF THE UPPER LOW AND ALSO A NW WIND FROM 10 TO 20 MPH IN THE HEART OF THE ARCTIC COLD. MSP DURING THE COLD WAVE IN EARLY JANUARY 1982 HAD A LOW TEMPERATURES OF -26 DEG F. IN FACT...LOWS ACROSS THE ENTIRE FA REACHED -25 TO -32 DEG F. THIS IS VERY SIMILAR THE FORECAST VALUES AHEAD. TODAY/S FORECAST HAS LOWS DROPPING BELOW ZERO SATURDAY EVENING AND NOT RISING ABOVE ZERO UNTIL WEDNESDAY. THIS IS A RUN OF 88 HOURS BELOW ZERO FOR MSP. NOT A TOP 10 RECORD... WHICH RUNS FROM 186 HOURS DOWN TO 130 HOURS. THE WORST STRETCH OF COLD IS FROM SUNDAY NIGHT THROUGH TUESDAY. LOWS SUNDAY NIGHT ARE FORECAST IN THE -25 TO -32 DEG F RANGE... WITH -27 FOR MSP (THIS WOULD TIE THE RECORD). THIS WOULD ALSO BE THE COLDEST MSP HAS BEEN SINCE DECEMBER 26TH 1996. THE ECE AND GFS MOS FOR MSP ARE -27 AND -29 DEG F RESPECTIVELY. THEN HAVE THE POTENTIAL FOR RECORD LOW HIGHS ON MONDAY WITH VALUES ONLY FORECAST IN THE -14 TO -20 DEG F RANGE. WE HAVE MSP AT -17 FOR THE HIGH ON MONDAY WHICH WOULD BE A RECORD LOW HIGH (-14). MONDAY NIGHT WE ARE BACK DOWN IN THE -20 TO -26 DEG F RANGE WITH HIGHS ON TUESDAY IN THE SINGLE DIGITS BELOW ZERO. AS MENTIONED EARLIER...NW WINDS WILL BE BLOWING THE WHOLE TIME. WIND CHILL VALUES SUNDAY NIGHT AND MONDAY WILL BE IN THE -50 TO -60 DEG F RANGE WITH VALUES MONDAY NIGHT AND TUESDAY MORNING IN THE -40 TO -50 DEG F RANGE. A WIND CHILL WARNING REMAINS IN EFFECT FROM 6 PM SATURDAY UNTIL NOON ON TUESDAY. THE BALANCE OF THE WORKWEEK WILL BE ONE OF TEMPERATURE MODERATION AS THE FLOW BECOMES MORE WESTERLY. HIGHS INCREASE FROM THE SINGLE DIGITS ABOVE ZERO ON WEDNESDAY TO THE UPPER 20S BY FRIDAY. THERE IS SOME DISAGREEMENT BETWEEN THE GFS/GEM AND EC ON HOW CLOSE WE WILL BE TO A SOUTHERN STREAM SNOW EVENT. THE GEM AND GFS WOULD JUST NICK OUR EASTERN AND SOUTHERN AREAS WHILE THE EC WOULD BRING THE SNOW THROUGH A NORTHERN STREAM FEATURE. COLLABORATION TODAY WAS TO KEEP VERY SMALL POPS CONFINED TO AREAS EAST AND SOUTH OF THE TWIN CITIES FOR WEDNESDAY/WEDNESDAY NIGHT. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1200 PM CST FRI JAN 3 2014 MAIN CHG TO THIS AVIATION TAF PERIOD IS TO CONCENTRATE ON TIMING OF THE FREEZING RAIN/SLEET DEVELOPMENT ACROSS WC MN/CENTRAL MN TOWARD 22-00Z. OTHERWISE...THE NEXT 6 HRS WILL BE MAINLY IFR/MVFR IN BLSN WITH CIGS HOLDING ARND 1K...TO LOCALLY 2-3K IN WC WI. A WARM LAYER ABV THE SFC (85H) IS NOTED IN WESTERN MN... AND AS FAR EAST AS AXN/MKT TO AEL BASED ON THE LATEST RAP AT 17Z. STRONG WSW WINDS AT 85H WILL CONTINUE TO ADVECT THESE HIGHER TEMPS EASTWARD INTO EASTERN MN BY 00Z. HOWEVER...THERE IS A SUBSTANTIAL DEEP SUB-FREEZING LAYER BLW 90H WHICH WILL LEAD TO THE REFREEZING OF THE PRECIPITATION. EC MN WILL LIKELY HOLD ONTO SLEET WITH STC/RWF/AXN A PERIOD OF FZRA/PL THRU THE EVENING BEFORE CHG OVER TO -SN AFT 6Z. DEPENDING UPON HOW MUCH PRECIPITATION DEVELOPS ACROSS SD IN THE NEXT FEW HRS...WILL DEPEND UPON HOW MUCH ACCUMULATION DEVELOPS. AM LEANING TOWARD AT LEAST 0.1 INCH OF ICE AT AXN THIS EVENING...WITH LESSER AMTS AT STC/RWF. RNH/EAU SHOULD STAY ALL SNOW...WITH A MIXTURE OF PL DURING THE LATE EVENING. WINDS WILL REMAIN FROM THE S/SSW AND GUSTY THIS AFTN/OVERNIGHT...BEFORE CHG TO THE SW/NW BY SATURDAY MORNING. CONFIDENCE IN FREEZING RAIN IS MODERATE AT AXN/STC...WITH LOWER CONFIDENCE AT RWF. KMSP... THIS FORECAST IS BASED ON THE 85H TEMPS HOLD NEAR +2C AND THE DEEPER LAYER OF TEMPS -10C BLW 90H WHICH WILL KEEP THE PRECIPITATION IN THE FORM OF LIGHT SLEET OR SNOW. CONFIDENCE OF FREEZING RAIN IS LOW AT THE AIRPORT...BUT IF ANY -FZRA DEVELOPS...IT WOULD BE AFT 2Z. SOME LOWER VSBYS MAY OCCUR THIS AFTN AS WINDS CONTINUE TO GUST UP TO 26 KTS. S/SSW WINDS CONTINUE THIS AFTN/EVENING...BECOMING MORE SW TONIGHT...THEN W/NW SATURDAY AFTN. /OUTLOOK FOR KMSP/ SAT NIGHT...VFR. NORTHWEST WIND 10 TO 20 KT. SUN THRU MON NIGHT...MVFR POSSIBLE. NORTHWEST WIND 10 TO 20 KT. TUE...MVFR CEILINGS POSSIBLE EARLY. WEST WIND 10 TO 15 KT. TUE NIGHT...VFR. WEST WIND 5 TO 10 KT BECOMING SOUTH. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ041-047- 048-054>057-064-065-067-073>077-082>085-091>093. WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR MNZ041>045-047>070-073>078-082>085-091>093. WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ042>045- 049>053-058>063-066-068>070-078. WI...WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR WIZ014>016-023>028. WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR WIZ014>016- 023>028. && $$ SHORT TERM...JLT LONG TERM...RAH AVIATION...JLT
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
1215 PM CST FRI JAN 3 2014 .UPDATE... ISSUED AT 1012 AM CST FRI JAN 3 2014 A WINTER WEATHER ADVISORY HAS BEEN EXTENDED THROUGH MID AFTERNOON FOR ALL OF WEST CENTRAL THROUGH SOUTH CENTRAL MN DUE TO BLOWING AND DRIFTING SNOW CONCERNS. AN ADDITIONAL ADVISORY IS BEING CONSIDERED FOR TONIGHT AND EARLY SATURDAY FOR MUCH OF THE CWA DUE TO MIXED PRECIPITATION CONCERNS AHEAD OF THE INCOMING ARCTIC FRONT. DETAILS ON THIS LATER. && .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 351 AM CST FRI JAN 3 2014 LATEST 11-3.9 MICRON IMAGERY SHOWS CLOUDS SPILLING DOWN THE WESTERN RIDGE AND MOVING INTO THE AREA AT THE CURRENT TIME. THE SURFACE RIDGE HAS SHIFTED TO THE EAST... ALLOWING WINDS TO BECOME SOUTHERLY... WHICH WHEN COMBINED WITH THE INCREASED CLOUD COVER HAS CAUSED TEMPERATURES TO BEGIN TO MOVE UPWARD ACROSS MUCH OF THE AREA. THIS TREND WILL CONTINUE THROUGH THE DAY TODAY... AS ROBUST WARM ADVECTION OCCURS ALOFT. SURFACE TEMPERATURES WILL RESPOND AS WELL... BUT THEY HAVE A LONG WAY TO GO... AND LOOK TO ONLY HAVE A CHANCE OF GETTING CLOSE TO FREEZING OVER THE WESTERN PORTION OF THE AREA. HOWEVER... 850MB TEMPERATURES LOOK TO GET WELL ABOVE FREEZING LATER THIS AFTERNOON INTO TONIGHT... WHICH WILL SPELL SOME PRECIPITATION-TYPE ISSUES ACROSS THE AREA AS THE SURFACE LOW AND COLD FRONT MOVE THROUGH THE REGION TONIGHT. AT THIS POINT... THE BEST COMBINATION OF WARM ADVECTION AND SATURATION LOOK TO OCCUR OFF TO OUR NORTH... BUT WE SHOULD SEE A WINDOW OF SOME LIGHT PCPN WITH THE COLD FRONT AND DPVA AHEAD OF THE UPPER SHORTWAVE. KEPT BEST POPS FROM LATE AFTERNOON THROUGH THE EVENING... WITH HIGHEST VALUES ACROSS THE NORTH CENTRAL AND NORTHEAST PORTION OF THE FORECAST AREA. WITH ABOVE FREEZING TEMPERATURES ALOFT AND BELOW FREEZING VALUES AT AND NEAR THE SURFACE... BOTH SLEET AND SOME LIGHT FREEZING RAIN WILL BE A POSSIBILITY WITH ANY PCPN THAT OCCURS. AS TEMPERATURES TURN SHARPLY COLDER LATER TONIGHT... ANY LINGERING PCPN WILL CHANGE BACK TO SNOW. AT THIS POINT... PCPN AMOUNTS LOOK LIGHT... AND IT IS TOUGH TO SAY IF/WHERE ANYTHING GREATER THAN A TENTH OF AN INCH MIGHT OCCUR. WITH THAT IN MIND... AM HOLDING OFF ON ISSUING ANY WINTER WEATHER HEADLINES DUE TO MIXED PCPN. HOWEVER... PRIOR TO THE ARRIVAL OF THE PCPN... WE WILL HAVE A PERIOD OF STRONG SOUTHERLY WINDS TODAY... PARTICULARLY NEAR THE BUFFALO RIDGE. THIS SHOULD CAUSE SOME BLOWING SNOW ISSUES FOR A GOOD PART OF THE DAY TODAY... SO WILL BE ISSUING A WINTER WEATHER ADVISORY FOR THE FAR WEST-CENTRAL AND SOUTHWEST PORTION OF THE AREA INTO MID-AFTERNOON. PATCHY BLOWING SNOW WILL IMPACT MUCH OF THE REST OF THE AREA AT TIMES... AS WINDS GUST NEAR 30 MPH. THERE COULD BE BLOWING SNOW CONCERNS ONCE AGAIN LATE TONIGHT INTO SATURDAY BEHIND THE COLD FRONT... BUT THOSE COULD BE MITIGATED BY ANY SLEET/FREEZING RAIN WHICH FALLS. NEEDLESS TO SAY... THIS IS ANOTHER ITEM WHICH WILL NEED TO BE MONITORED... AND WILL CERTAINLY BE MENTIONED IN THE FORECAST. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 351 AM CST FRI JAN 3 2014 THE FOCUS ON THE LONG TERM IS SQUARELY ON THE INTENSE...POSSIBLY RECORD BREAKING COLD AIR OUTBREAK LATE THIS WEEKEND AND EARLY NEXT WEEK. THIS HAS ALL THE MARKINGS OF A HISTORIC EVENT...AND A FORECASTER IS LUCKY IF HE/SHE SEES ONE LIKE THIS IN THEIR ENTIRE CAREER. SURPRISINGLY FOR SUCH AN EXTREME EVENT...THERE IS VERY HIGH CONFIDENCE THROUGH EARLY NEXT WEEK OF IT OCCURRING...ASIDE FROM SMALLER DETAILS SUCH AS WHETHER WE CAN BREAK ALL TIME COLD RECORD HIGHS MONDAY. EVEN MOS IS CALLING FOR ALL TIME RECORD HIGHS TO BE TIED OR BROKEN. A WIND CHILL WARNING HAS BEEN ISSUED THROUGH THE COLD AIR OUTBREAK FOR THE 100 PERCENT CHANCE OF -35 OR COLDER WIND CHILLS OCCURRING. THE SOURCE REGION OF THIS AIR MASS IS IN NUNAVUT WHERE CURRENT TEMPERATURES ARE AROUND -30. MODELS SHOW LITTLE OR NO MODERATION AS THIS CHUNK OF ARCTIC AIR DIVES SOUTHEAST INTO THE UPPER MIDWEST LATE THIS WEEKEND DUE TO LIMITED SUN AND CONTINUOUS SNOW PACK. THE CORE OF THE COLDEST AIR WILL PASS DIRECTLY OVERHEAD LATE SUNDAY AFTERNOON AND SUNDAY EVENING. GUIDANCE HAS BEEN RATHER STABLE IN DEPICTING NEAR RECORD COLD AIR FOR SEVERAL RUNS. BOTH GFS AND ECMWF MOS GUIDANCE ARE IN THE 25 TO 35 BELOW RANGE FOR LOWS SUNDAY NIGHT AND HIGHS IN THE 15 TO 20 BELOW RANGE MONDAY. THE MOS NUMBERS FOR MONDAY ARE BOLSTERED BY 925 MB TEMPS IN THE -29 TO -34C RANGE WHICH WOULD ALSO TRANSLATE TO HIGHS IN THE UPPER TEENS BELOW ZERO IF WE CAN EVEN MIX THAT DEEP. HAVE ADJUSTED THE GRIDS DOWNWARD TO REFLECT THE GOOD CONSISTENCY. THE COLDEST HIGH EVER RECORDED AT MSP IS -17F...OCCURRING WITH THE INFAMOUS COLD OUTBREAKS OF 2/2/1996 AND 12/23/1983. THE FORECAST CURRENTLY CALLS FOR THAT ALL TIME RECORD TO BE TIED. USUALLY FOR SUCH EXTREME TEMPS TO OCCUR...CLEAR SKIES...CALM WINDS AND IDEAL RADIATIONAL COOLING CONDITIONS WOULD BE NECESSARY. IT WILL NOT BE NECESSARY IN THIS AIRMASS. IN FACT...CYCLONIC FLOW ALOFT MAY BRING CLOUDS AND OCCASIONAL ICE CRYSTALS. IF THE AIR TEMPERATURES WERE NOT IMPRESSIVE ENOUGH...PERHAPS THE WIND ACCOMPANYING THE BITTER COLD AIR IS. NORTHWEST WINDS OF 10 TO 20 MPH THROUGHOUT THE OUTBREAK WILL LEAD TO WIND CHILLS DROPPING TO 35 TO 50 BELOW...EXCEPT BETWEEN 50 AND 60 BELOW SUNDAY NIGHT AND MONDAY MORNING. BOTTOM LINE...IT WILL BE COLD...EXTREMELY COLD. A COUPLE OTHER NOTES...BLOWING SNOW IS POSSIBLE AT TIMES THROUGH EARLY NEXT WEEK - PARTICULARLY IMMEDIATELY BEHIND THE ARCTIC BOUNDARIES IN WESTERN MINNESOTA WHERE WINDS MAY GUST TO 35 MPH. MAY NEED A HEADLINE FOR THIS...BUT CONFIDENCE IS NOT HIGH ENOUGH YET TO JUMP ON THAT. BY MID TO LATE NEXT WEEK...MUCH MILDER AIR WILL PUSH EAST ACROSS THE CONUS AS ZONAL FLOW TAKES OVER. THERE ARE STILL NO SIGNIFICANT SNOW STORMS ON THE HORIZON. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z SATURDAY AFTERNOON) ISSUED AT 1200 PM CST FRI JAN 3 2014 MAIN CHG TO THIS AVIATION TAF PERIOD IS TO CONCENTRATE ON TIMING OF THE FREEZING RAIN/SLEET DEVELOPMENT ACROSS WC MN/CENTRAL MN TOWARD 22-00Z. OTHERWISE...THE NEXT 6 HRS WILL BE MAINLY IFR/MVFR IN BLSN WITH CIGS HOLDING ARND 1K...TO LOCALLY 2-3K IN WC WI. A WARM LAYER ABV THE SFC (85H) IS NOTED IN WESTERN MN... AND AS FAR EAST AS AXN/MKT TO AEL BASED ON THE LATEST RAP AT 17Z. STRONG WSW WINDS AT 85H WILL CONTINUE TO ADVECT THESE HIGHER TEMPS EASTWARD INTO EASTERN MN BY 00Z. HOWEVER...THERE IS A SUBSTANTIAL DEEP SUB-FREEZING LAYER BLW 90H WHICH WILL LEAD TO THE REFREEZING OF THE PRECIPITATION. EC MN WILL LIKELY HOLD ONTO SLEET WITH STC/RWF/AXN A PERIOD OF FZRA/PL THRU THE EVENING BEFORE CHG OVER TO -SN AFT 6Z. DEPENDING UPON HOW MUCH PRECIPITATION DEVELOPS ACROSS SD IN THE NEXT FEW HRS...WILL DEPEND UPON HOW MUCH ACCUMULATION DEVELOPS. AM LEANING TOWARD AT LEAST 0.1 INCH OF ICE AT AXN THIS EVENING...WITH LESSER AMTS AT STC/RWF. RNH/EAU SHOULD STAY ALL SNOW...WITH A MIXTURE OF PL DURING THE LATE EVENING. WINDS WILL REMAIN FROM THE S/SSW AND GUSTY THIS AFTN/OVERNIGHT...BEFORE CHG TO THE SW/NW BY SATURDAY MORNING. CONFIDENCE IN FREEZING RAIN IS MODERATE AT AXN/STC...WITH LOWER CONFIDENCE AT RWF. KMSP... THIS FORECAST IS BASED ON THE 85H TEMPS HOLD NEAR +2C AND THE DEEPER LAYER OF TEMPS -10C BLW 90H WHICH WILL KEEP THE PRECIPITATION IN THE FORM OF LIGHT SLEET OR SNOW. CONFIDENCE OF FREEZING RAIN IS LOW AT THE AIRPORT...BUT IF ANY -FZRA DEVELOPS...IT WOULD BE AFT 2Z. SOME LOWER VSBYS MAY OCCUR THIS AFTN AS WINDS CONTINUE TO GUST UP TO 26 KTS. S/SSW WINDS CONTINUE THIS AFTN/EVENING...BECOMING MORE SW TONIGHT...THEN W/NW SATURDAY AFTN. /OUTLOOK FOR KMSP/ SAT NIGHT...VFR. NORTHWEST WIND 10 TO 20 KT. SUN THRU MON NIGHT...MVFR POSSIBLE. NORTHWEST WIND 10 TO 20 KT. TUE...MVFR CEILINGS POSSIBLE EARLY. WEST WIND 10 TO 15 KT. TUE NIGHT...VFR. WEST WIND 5 TO 10 KT BECOMING SOUTH. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WINTER WEATHER ADVISORY UNTIL 3 PM CST THIS AFTERNOON FOR MNZ041- 047-048-054>057-064-065-067-073>077-082>085-091>093. WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR MNZ041>045-047>070-073>078-082>085-091>093. WI...WIND CHILL WARNING FROM 6 PM SATURDAY TO NOON CST TUESDAY FOR WIZ014>016-023>028. && $$ UPDATE...RAH SHORT TERM... LONG TERM...BORGHOFF AVIATION...JLT
AREA FORECAST DISCUSSION...UPDATED
NWS ST LOUIS MO
813 PM CST Sat Jan 4 2014 .UPDATE: Issued at 810 PM CST Sat Jan 4 2014 Going to be making a few tweaks to the going forecast based on the latest model data that is coming in. 1. Precipitation will stay in liquid form across far southern CWA for much of the overnight period, and perhaps into Sunday morning. Still forecasting just over six inches for storm total - so no headline changes needed. 2. Latest NAM, HRRR and RAP model runs show intense upward vertical motion and convective potential due to steep lapse rates and hints of true CAPE, or upright convective potentional, tomorrow morning across the warned area and therefore will be adding mention of thunder to forecast. Certainly potential for localized snowfall totals over 12 inches. Updated forecast and graphics will be out by 9 p.m. CVKING && .SHORT TERM: (Through Tuesday Afternoon) Issued at 342 PM CST Sat Jan 4 2014 (Tonight - Sunday) Main forecast issue here is major winter storm set to impact the entire area. Forecast by and large is on track from previous shifts with only minor adjustments made. A major winter storm is set to develop later tonight and continue thru much of the day on Sunday. The components for this storm include a strong shortwave over the east-central Rockies which is expected to drop a bit further south before moving east into the Mid-MS valley, being steered on this track by a powerful Polar vortex located over northern MN and western Ontario. By nightfall Sunday afternoon-evening, pcpn is expected to have ended over our region, other than some stray flurries. In the meantime, a cold front, now entering northeast MO, will continue to push SE thru our region, getting thru the final SE MO and S IL counties by daybreak Sunday. Temps will fall several degrees behind this front and will have no problem dropping into the 20s and below, given this is the leading edge of very bitter cold air. Ahead of the front, however, temps will struggle to drop below freezing with clouds and south winds. Pcpn associated with the front has already taken shape in NW MO and S IA and N IL and this band of snow will gradually drop SE into the UIN area this evening and into mid-MO by late evening before some measure of re-organization takes place as the main system strengthens to the W. Pcpn-types may be rain or sleet early but should quickly become all snow with approach of or passage of cold front and should only be a minor concern. The stronger system snow will merge with and overtake the frontal snow late tonight as incredible lift thanks to frontogenesis and jet dynamics enters central and SE MO and then propagates northeastward into STL Metro Sunday morning and eventually into SW IL for a good portion on Sunday. Goree-Younkin-Brown technique continues to target a track from the central Ozarks to just S and E of downtown STL City and curving northeastward into IL for heaviest snowfall potential, with a foot or more of new snow not out of the question. Snowfall amounts associated with maps represent median, most likely values, but higher amounts near the track described above quite possible with higher liquid-to-snow ratios (LSRs) as very cold air builds in at the lo levels. During its peak from very late tonight thru Sunday morning and into early afternoon, snowfall rates at times may top 2" per hour. The visibility reductions with snow combined with wind gusts of 30-35 mph will result in near blizzard conditions for a time on Sunday. When it is done by nightfall early Sunday evening, snowfall amounts from 4-6" can be expected along a UIN-COU axis with 8-12" for STL metro and areas just S and E with locally higher amounts. However, that is only the beginning. Blowing snow will begin to be a real issue by late Sunday morning on once enough snow has fallen and strong winds kick in from the strong CAA. This will lead to impassable roads in places and very lo visibilities. Winter storm headline types will continue with only slight adjustments to timing at the end. (Sunday Night - Tuesday) Main forecast issue for this period will be extreme cold, with winds dropping wind chill values to dangerous levels. Lingering issues from the winter storm will also be a concern. Blowing snow issues will continue thru at least Sunday night and perhaps into Monday as the coldest air of my career builds in, maintaining the strong winds, acting upon what should be a deep snowpack across much of our region. Of greater concern is widespread sub-zero temps...dipping to 5 to 15 below Sunday night...only rising to zero to 5 below on Monday... dropping again to zero to 10 below Monday night...finally bobbing above zero on Tuesday. We have not seen a prolonged period of sub-zero for most locations for two or three decades and this cannot be emphasized enough...this cold will be extremely dangerous when combined with the wind...giving us once-in-a-generation magnitude of cold...taking mere minutes to frostbite on exposed skin. Despite being a couple days out, went ahead and will issue a wind chill warning to elevate the word on the danger that the cold and wind will bring to our area. TES .LONG TERM: (Wednesday through Next Saturday) Issued at 342 PM CST Sat Jan 4 2014 The moderation in temperatures that begins on Tuesday will continue throughout the week as longwave pattern transitions to a zonal flow pattern over the CONUS, shunting the coldest air to our north. By Friday and Saturday it would appear that high temps will finally rebound to near average temperatures, ranging from the middle 30s in the north to the middle 40s in the south. Medium range solutions are still forecasting several shortwave trofs to push into the Central U.S. during the latter half of the week, with ascent associated with these features combining with isentropic lift and moisture advection in the return flow to produce several chances for precipitation. As mentioned in previous AFD, p-type gets a bit tricky with time: initially all snow, but with a slow warming throughout the lower troposphere ptype there may be a transition to sleet over southern areas Wednesday night and Thursday. By Friday, continuing warming appears to support all rain, with a threat of freezing rain during the morning as surface temps are below 32 at that time. TRUETT && .AVIATION: (For the 00z TAFs through 00z Sunday Evening) Issued at 527 PM CST Sat Jan 4 2014 A number of uncertainties remain regarding this system. Mainly, timing of onset precip and timing of heavier SN. Latest guidance suggests that precip may begin as DZ/FZDZ or as a mix of RA/IP. Actual precip may also end a little sooner than TAF suggests. However, as visbys will likely stay within the MVFR range, or perhaps lower, due to blowing snow, only added another group when cigs are expected to lift. Will likely need to update later to include better timing of heaviest SN. For now, heaviest SN shud reach COU late tonight as the upper trof reaches the region. This shud hold off for SUS/CPS until right around sunrise. UIN may also not see the lowest visbys until near sunrise, but more uncertainty exists. When the system exits, snowfall amounts around 4 inches for COU/UIN and 10 to 12 inches for SUS/CPS. Specifics for KSTL: Other than what is mentioned above, heaviest SN shud reach terminal somewhere between 12z and 15z and shud persist thru about 18z. Total snowfall is currently forecast around 10 inches. Tilly && .CLIMATE: Issued at 1130 PM CST Thu Jan 2 2014 Last occurrence of a min temp of zero degrees or lower at KSTL: 0 on January 21, 2011 -5 on January 5, 1999 RECORD LOW TEMPERATURES January 6 January 7 St. Louis -11/1884 -14/1912 Columbia -12/1912 -20/1912 Quincy -9/1970 -19/1912 RECORD LOW MAXIMUM TEMPERATURES January 6 January 7 St. Louis 0/1912 0/1912 Columbia -3/1912 2/1912 Quincy -3/1912 -2/1912 Phillipson && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WINTER STORM WARNING from Midnight tonight to 6 PM CST Sunday FOR Crawford MO-Iron MO-Jefferson MO-Madison MO-Reynolds MO- St. Francois MO-Ste. Genevieve MO-Washington MO. WIND CHILL WARNING from Midnight Sunday Night to Noon CST Tuesday FOR Crawford MO-Iron MO-Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO-Washington MO. WINTER STORM WARNING until 3 PM CST Sunday FOR Franklin MO- Gasconade MO-Lincoln MO-Montgomery MO-Osage MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WIND CHILL WARNING from 6 PM Sunday to Noon CST Tuesday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO- Gasconade MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WINTER WEATHER ADVISORY until 3 PM CST Sunday FOR Audrain MO- Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO- Moniteau MO-Monroe MO-Pike MO-Ralls MO-Shelby MO. IL...WINTER STORM WARNING from Midnight tonight to 6 PM CST Sunday FOR Bond IL-Clinton IL-Fayette IL-Marion IL-Monroe IL- Montgomery IL-Randolph IL-St. Clair IL-Washington IL. WIND CHILL WARNING from Midnight Sunday Night to Noon CST Tuesday FOR Randolph IL. WINTER STORM WARNING until 3 PM CST Sunday FOR Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Madison IL. WIND CHILL WARNING from 6 PM Sunday to Noon CST Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-St. Clair IL-Washington IL. WINTER WEATHER ADVISORY until 3 PM CST Sunday FOR Adams IL-Brown IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1020 AM CST FRI JAN 3 2014 .UPDATE... ISSUED AT 945 AM CST FRI JAN 3 2014 NO CHANGES TO THIS UPDATE...AS WE ARE STILL TRYING TO GET TIMING ON POTENTIAL BLIZZARD. THERE WILL BE AN AREA OF MIXED PRECIP MOVING FROM WEST TO EAST THIS AFTERNOON...AND THIS COULD CREATE ICY CONDITIONS. THIS IS HANDLED WELL AND NO CHANGES PLANNED. SOUTHERLY WINDS SHOULD SLOWLY DECREASE AND BLOWING/DRIFTING SHOULD DIMINISH IN THE VALLEY. UPDATE ISSUED AT 701 AM CST FRI JAN 3 2014 FCST ON TRACK. DID ADJUST TEMPS SLIGHTLY THIS MORNING BUT OVERALL THINGS SEEM OK. REPORT OF AROUND AN INCH OF NEW SNOW IN WARROAD- BAUDETTE AREA. WINDS STARTING TO DIMINISH A BIT IN THE RRV AND THIS TREND WILL CONTINUE THIS MORNING. WILL HAVE TO WATCH DEVELOPMENT OF PRECIP IN ERN MT. LATEST RAP MORE AGGRESSIVE IN BRINGING IN PRECIP SOUTH OF THE LOW THIS AFTN AND THIS COULD CAUSE ISSUES IF HEAVY ENOUGH DUE TO FREEZING RAIN/SLEET CHANCES. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 318 AM CST FRI JAN 3 2014 MANY ISSUES TO START WITH. SURFACE LOW PRESSURE EAST OF CALGARY ALBERTA ATTM AND THIS WILL TRACK AS EXPECTED TO NEAR GRAND FORKS BY 00Z...THEN EAST THRU NRN MN TONIGHT. WARM ADVECTION LIGHT SNOWS IN FAR NW MN WILL CONTINUE THIS MORNING BEFORE MORE SNOW ASSOC WITH SFC LOW ARRIVES IN THAT AREA THIS AFTN-TONIGHT. COORD WITH DLH AND BASED ON SNOWFALL FCST OF 3-5 INCHES IN ROSEAU-WARROAD- BAUDETTE-WASKISH WILL GO WINTER WX ADVISORY 12Z FRI-12Z SAT. SOUTH OF THE LOW TRACK EXPECT A WARM AIR SURGE EAST THIS AFTN INTO THE DVL BASIN MIDDAY AND INTO THE RED RIVER VALLEY MID TO LATE AFTN WITH TEMPS LOWER 30S IN DVL BASIN AND UPPER 20S-LOWER 30S IN THE MID/SRN RRV. SOUTH OF THE LOW NOT MUCH PRECIP...BUT ALL MODELS INDICATE SOME LIGHT PRECIP DEVELOPING AHEAD OF SHARPENING 500 MB TROUGH IN SE ND INTO WCNTRL MN MID TO LATE AFTN. IN THIS WARMER AIR ALOFT REGION...ANY PRECIP THAT FALLS WOULD BE OF A LIGHT FREEZING RAIN/SLEET TYPE. AMOUNTS WILL BE LIGHT. NORTH OF THE LOW SNOW WILL DROP INTO NRN ND MID AFTN INTO LATE AFTN. SFC LOW POSITION NEAR GRAND FORKS AT 00Z WOULD MEAN NORTH-NORTHWEST WINDS WILL BEGIN TO ENTER FAR NW FCST AREA-FAR NRN RRV AROUND 21-22Z AND THEN SPREAD SOUTHWARD BEHIND THE LOW AFTER 00Z. GFS MODEL A BIT MORE AGGRESSIVE WITH PRECIP/WIND THAN PAST RUNS AND 06Z NAM PRETTY STRONG TOO AND WITH A SHARP SURGE OF COLD SFC-925 MB TEMPS AND GOOD MIXED LAYER TO 925 MB WHERE WINDS WILL BE 45 KTS WOULD EXPECT BLIZZARD CONDITIONS TO DEVELOP. BASED ON TIMING OF WINDS WILL HOIST BLIZZARD WARNING FOR FAR NRN RRV/DVL BASIN STARTING AT 21Z FRI THRU 15Z SAT. FOR THE REST OF THE RED RIVER VALLEY GRAND FORKS SOUTHWARD BECAUSE OF START TIME NOT TIL AFTER 00Z...WILL KEEP WATCH AND ALLOW DAYSHIFT TO FINE TUNE BEGINNING OF WARNING HEADLINES. FRESH SNOWFALL WILL BE LIGHT IN THE NRN VALLEY WITH AN INCH OR MAYBE TWO CANDO-GRAFTON-HALLOCK WITH THAT HEAVIER SNOWFALL MORE TOWARD ROSEAU EASTWARD. FOR AREAS SOUTH OF HIGHWAY TWO GENERALLY LESS THAN AN INCH. FOR AREAS OF MINNESOTA NOT IN LAKE OF THE WOODS AREA NOR IN THE RED RIVER VALLEY (TVF-BJI SOUTHWARD) COULD SEE WINTER WX ADVISORY CONDITIONS WITH SOME BLOWING SNOW/SNOW SHOWERS TONIGHT BUT WILL LET LATER SHIFT DETERMINE EXTENT AND TIMING OF THAT. WINDS WILL SLOWLY SUBSIDE SATURDAY MORNING WITH BLOWING SNOW CONDITIONS BECOME MORE LIMITED AND CLEARING WORKS IN. TEMPS WILL FALL SLOWLY DURING THE DAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 318 AM CST FRI JAN 3 2014 CLEAR TO PARTLY CLOUDY SKY SAT NIGHT WILL LEAD TO A COLD NIGHT WITH NORTHWEST WINDS HOLDING UP AND WIND CHILL WILL DROP INTO ADVISORY AND THEN WARNING CRITERIA BY 12Z SUN. FOR SUNDAY...EXPECT MAIN COLD SHOT AT LEAST AT 925-850 MB LAYER AS UPPER LOW DROPS SOUTH. EXPECT AN INCREASE IN CLOUDS AND FLURRIES TO MOVE IN FROM THE NORTH SUN-SUN NIGHT. WHILE CLOUDS WILL KEEP LOW TEMPS SUN NIGHT FROM GOING OFF THE DEEP END...TIGHT GRADIENT BETWEEN SFC LOW IN WESTERN QUEBEC AND HIGH PRESSURE IN ALBERTA- SASK-MONTANA WILL CREATE A STIFF NORTHWEST BREEZE AND VERY LOW WIND CHILLS. WILL ADDRESS WIND CHILL WARNINGS AS NEEDED ONCE THIS BLIZZARD SYSTEM DEPARTS. MONDAY THROUGH WEDNESDAY NIGHT...00 UTC GFS/ECMWF ARE IN GOOD AGREEMENT. BOTH SHOW A DEEP TROUGH ACROSS THE EASTERN CONUS ON MONDAY MOVING INTO EASTERN CANADA BY MID-WEEK WITH FLOW ALOFT BECOMING MORE WESTERLY ACROSS THE NORTHERN PLAINS. WEAK SHORT-WAVES WILL DROP SOUTH FROM CANADA...BUT WITH SURFACE HIGH PRESSURE AND LITTLE MOISTURE...WILL KEEP THE FORECAST DRY. THE DEEP FREEZE WILL CONTINUE ON MONDAY WITH HIGHS IN THE TEENS BELOW ZERO...BUT EXPECT A GRADUAL WARMING TREND THEREAFTER AS A BUILDING RIDGE ACROSS THE WESTERN CONUS SLOWLY TRANSLATES TO THE EAST. HIGHS BY WEDNESDAY SHOULD RISE ABOVE ZERO WITH 850 HPA TEMPERATURES AROUND -12 C. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 701 AM CST FRI JAN 3 2014 VERY DIFFICULT AVIATION FORECAST. AREAS OF IFR CIGS AT FAR/GFK MAINLY DUE TO BLOWING SNOW OVER THE SENSOR. OTHERWISE WITHOUT BLOWING SNOW MOST CIGS IN THE LOW END VFR RANGE. VSYBS REDUCED IN BLOWING SNOW TO 1-3SM IN THE RRV WILL IMPROVE TO P6SM AS WELL BY LATE MORNING/MIDDAY AS WINDS DIMINISH. QUESTION IS CHANCE FOR FREEZING PRECIP THIS AFTN ESP AT GFK/FAR. DID NOT INCLUDE IN TAF DUE TO HIGH UNCERTAINTY ON WHEN/HOW MUCH. WINDS WILL TURN NORTH- NORTHWEST WITH GUSTS TO 35 KTS (OR HIGHER) FOR A PERIOD THIS EVE FROM NORTH TO SOUTH THROUGH DVL/RRV BASIN. CIGS LIKELY TO LOWER AND VSBYS TOO TO IFR LEVELS IN THIS REGION. A BIT HIGHER VSBYS BEMIDJI BUT STILL SOME SNOWFALL TONIGHT WITH IFR CIGS LATER TONIGHT. FOR THIEF RIVER FALLS DUE TO CONTINUED CEILOMETER OUTAGE AND AWAITING A REPLACEMENT WENT AMENDMENT NOT SCHEDULED (AMD NOT SKED) DUE TO HIGH UNCERTAINTY OF CIGS TODAY-TONIGHT AND NO REAL WAY TO CHECK IN REAL TIME, SO UPDATES WILL BE LIMITED TO GENERALLY MAJOR TAF ISSUANCE TIMES. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...BLIZZARD WATCH FROM 6 PM CST THIS EVENING THROUGH SATURDAY MORNING FOR NDZ024-026>030-038-039-049-052-053. BLIZZARD WARNING FROM 3 PM THIS AFTERNOON TO 9 AM CST SATURDAY FOR NDZ006>008-014>016-054. MN...BLIZZARD WATCH FROM 6 PM CST THIS EVENING THROUGH SATURDAY MORNING FOR MNZ001>003-027-029-030-040. BLIZZARD WARNING FROM 3 PM THIS AFTERNOON TO 9 AM CST SATURDAY FOR MNZ004-007. WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ005-006- 009. && $$ UPDATE...DK SHORT TERM...RIDDLE LONG TERM...RIDDLE/ROGERS AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
710 AM CST FRI JAN 3 2014 .UPDATE... ISSUED AT 701 AM CST FRI JAN 3 2014 FCST ON TRACK. DID ADJUST TEMPS SLIGHTLY THSI MORNING BUT OVERALL THINGS SEEM OK. REPORT OF AROUND AN INCH OF NEW SNOW IN WARROAD- BAUDETTE AREA. WINDS STARTING TO DIMINISH A BIT IN THE RRV AND THIS TREND WILL CONTINUE THIS MORNING. WILL HAVE TO WATCH DEVELOPMENT OF PRECIP IN ERN MT. LATEST RAP MORE AGGRESSIVE IN BRINGING IN PRECIP SOUTH OF THE LOW THIS AFTN AND THIS COULD CAUSE ISSUES IF HEAVY ENOUGH DUE TO FREEZING RAIN/SLEET CHANCES. && .SHORT TERM...(TODAY THROUGH SATURDAY) ISSUED AT 318 AM CST FRI JAN 3 2014 MANY ISSUES TO START WITH. SURFACE LOW PRESSURE EAST OF CALGARY ALBERTA ATTM AND THIS WILL TRACK AS EXPECTED TO NEAR GRAND FORKS BY 00Z...THEN EAST THRU NRN MN TONIGHT. WARM ADVECTION LIGHT SNOWS IN FAR NW MN WILL CONTINUE THIS MORNING BEFORE MORE SNOW ASSOC WITH SFC LOW ARRIVES IN THAT AREA THIS AFTN-TONIGHT. COORD WITH DLH AND BASED ON SNOWFALL FCST OF 3-5 INCHES IN ROSEAU-WARROAD- BAUDETTE-WASKISH WILL GO WINTER WX ADVISORY 12Z FRI-12Z SAT. SOUTH OF THE LOW TRACK EXPECT A WARM AIR SURGE EAST THIS AFTN INTO THE DVL BASIN MIDDAY AND INTO THE RED RIVER VALLEY MID TO LATE AFTN WITH TEMPS LOWER 30S IN DVL BASIN AND UPPER 20S-LOWER 30S IN THE MID/SRN RRV. SOUTH OF THE LOW NOT MUCH PRECIP...BUT ALL MODELS INDICATE SOME LIGHT PRECIP DEVELOPING AHEAD OF SHARPENING 500 MB TROUGH IN SE ND INTO WCNTRL MN MID TO LATE AFTN. IN THIS WARMER AIR ALOFT REGION...ANY PRECIP THAT FALLS WOULD BE OF A LIGHT FREEZING RAIN/SLEET TYPE. AMOUNTS WILL BE LIGHT. NORTH OF THE LOW SNOW WILL DROP INTO NRN ND MID AFTN INTO LATE AFTN. SFC LOW POSITION NEAR GRAND FORKS AT 00Z WOULD MEAN NORTH-NORTHWEST WINDS WILL BEGIN TO ENTER FAR NW FCST AREA-FAR NRN RRV AROUND 21-22Z AND THEN SPREAD SOUTHWARD BEHIND THE LOW AFTER 00Z. GFS MODEL A BIT MORE AGGRESSIVE WITH PRECIP/WIND THAN PAST RUNS AND 06Z NAM PRETTY STRONG TOO AND WITH A SHARP SURGE OF COLD SFC-925 MB TEMPS AND GOOD MIXED LAYER TO 925 MB WHERE WINDS WILL BE 45 KTS WOULD EXPECT BLIZZARD CONDITIONS TO DEVELOP. BASED ON TIMING OF WINDS WILL HOIST BLIZZARD WARNING FOR FAR NRN RRV/DVL BASIN STARTING AT 21Z FRI THRU 15Z SAT. FOR THE REST OF THE RED RIVER VALLEY GRAND FORKS SOUTHWARD BECAUSE OF START TIME NOT TIL AFTER 00Z...WILL KEEP WATCH AND ALLOW DAYSHIFT TO FINE TUNE BEGINNING OF WARNING HEADLINES. FRESH SNOWFALL WILL BE LIGHT IN THE NRN VALLEY WITH AN INCH OR MAYBE TWO CANDO-GRAFTON-HALLOCK WITH THAT HEAVIER SNOWFALL MORE TOWARD ROSEAU EASTWARD. FOR AREAS SOUTH OF HIGHWAY TWO GENERALLY LESS THAN AN INCH. FOR AREAS OF MINNESOTA NOT IN LAKE OF THE WOODS AREA NOR IN THE RED RIVER VALLEY (TVF-BJI SOUTHWARD) COULD SEE WINTER WX ADVISORY CONDITIONS WITH SOME BLOWING SNOW/SNOW SHOWERS TONIGHT BUT WILL LET LATER SHIFT DETERMINE EXTENT AND TIMING OF THAT. WINDS WILL SLOWLY SUBSIDE SATURDAY MORNING WITH BLOWING SNOW CONDITIONS BECOME MORE LIMITED AND CLEARING WORKS IN. TEMPS WILL FALL SLOWLY DURING THE DAY. .LONG TERM...(SATURDAY NIGHT THROUGH THURSDAY) ISSUED AT 318 AM CST FRI JAN 3 2014 CLEAR TO PARTLY CLOUDY SKY SAT NIGHT WILL LEAD TO A COLD NIGHT WITH NORTHWEST WINDS HOLDING UP AND WIND CHILL WILL DROP INTO ADVISORY AND THEN WARNING CRITERIA BY 12Z SUN. FOR SUNDAY...EXPECT MAIN COLD SHOT AT LEAST AT 925-850 MB LAYER AS UPPER LOW DROPS SOUTH. EXPECT AN INCREASE IN CLOUDS AND FLURRIES TO MOVE IN FROM THE NORTH SUN-SUN NIGHT. WHILE CLOUDS WILL KEEP LOW TEMPS SUN NIGHT FROM GOING OFF THE DEEP END...TIGHT GRADIENT BETWEEN SFC LOW IN WESTERN QUEBEC AND HIGH PRESSURE IN ALBERTA- SASK-MONTANA WILL CREATE A STIFF NORTHWEST BREEZE AND VERY LOW WIND CHILLS. WILL ADDRESS WIND CHILL WARNINGS AS NEEDED ONCE THIS BLIZZARD SYSTEM DEPARTS. MONDAY THROUGH WEDNESDAY NIGHT...00 UTC GFS/ECMWF ARE IN GOOD AGREEMENT. BOTH SHOW A DEEP TROUGH ACROSS THE EASTERN CONUS ON MONDAY MOVING INTO EASTERN CANADA BY MID-WEEK WITH FLOW ALOFT BECOMING MORE WESTERLY ACROSS THE NORTHERN PLAINS. WEAK SHORT-WAVES WILL DROP SOUTH FROM CANADA...BUT WITH SURFACE HIGH PRESSURE AND LITTLE MOISTURE...WILL KEEP THE FORECAST DRY. THE DEEP FREEZE WILL CONTINUE ON MONDAY WITH HIGHS IN THE TEENS BELOW ZERO...BUT EXPECT A GRADUAL WARMING TREND THEREAFTER AS A BUILDING RIDGE ACROSS THE WESTERN CONUS SLOWLY TRANSLATES TO THE EAST. HIGHS BY WEDNESDAY SHOULD RISE ABOVE ZERO WITH 850 HPA TEMPERATURES AROUND -12 C. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z SATURDAY MORNING) ISSUED AT 701 AM CST FRI JAN 3 2014 VERY DIFFICULT AVIATION FORECAST. AREAS OF IFR CIGS AT FAR/GFK MAINLY DUE TO BLOWING SNOW OVER THE SENSOR. OTHERWISE WITHOUT BLOWING SNOW MOST CIGS IN THE LOW END VFR RANGE. VSYBS REDUCED IN BLOWING SNOW TO 1-3SM IN THE RRV WILL IMPROVE TO P6SM AS WELL BY LATE MORNING/MIDDAY AS WINDS DIMINISH. QUESTION IS CHANCE FOR FREEZING PRECIP THIS AFTN ESP AT GFK/FAR. DID NOT INCLUDE IN TAF DUE TO HIGH UNCERTAINITY ON WHEN/HOW MUCH. WINDS WILL TURN NORTH- NORTHWEST WITH GUSTS TO 35 KTS (OR HIGHER) FOR A PERIOD THIS EVE FROM NORTH TO SOUTH THROUGH DVL/RRV BASIN. CIGS LIKELY TO LOWER AND VSBYS TOO TO IFR LEVELS IN THIS REGION. A BIT HIGHER VSBYS BEMIDJI BUT STILL SOME SNOWFALL TONIGHT WITH IFR CIGS LATER TONIGHT. FOR THIEF RIVER FALLS DUE TO CONTINUED CEILOMETER OUTAGE AND AWAITING A REPLACEMENT WENT AMENDMENT NOT SCHEDULED (AMD NOT SKED) DUE TO HIGH UNCERTAINITY OF CIGS TODAY-TONIGHT AND NO REAL WAY TO CHECK IN REAL TIME, SO UPDATES WILL BE LIMITED TO GENERALLY MAJOR TAF ISSUANCE TIMES. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...BLIZZARD WATCH FROM 6 PM CST THIS EVENING THROUGH SATURDAY MORNING FOR NDZ024-026>030-038-039-049-052-053. BLIZZARD WARNING FROM 3 PM THIS AFTERNOON TO 9 AM CST SATURDAY FOR NDZ006>008-014>016-054. MN...BLIZZARD WATCH FROM 6 PM CST THIS EVENING THROUGH SATURDAY MORNING FOR MNZ001>003-027-029-030-040. BLIZZARD WARNING FROM 3 PM THIS AFTERNOON TO 9 AM CST SATURDAY FOR MNZ004-007. WINTER WEATHER ADVISORY UNTIL 6 AM CST SATURDAY FOR MNZ005-006- 009. && $$ UPDATE...RIDDLE SHORT TERM...RIDDLE LONG TERM...RIDDLE/ROGERS AVIATION...RIDDLE
AREA FORECAST DISCUSSION
NWS BISMARCK ND
103 AM CST FRI JAN 3 2014 .UPDATE... ISSUED AT 102 AM CST FRI JAN 3 2014 ADDED A MENTION OF PATCHY BLOWING SNOW TO MUCH OF WESTERN AND CENTRAL NORTH DAKOTA FOR THE REMAINDER OF THE NIGHT. THE 06-07 UTC SOUTHERLY WINDS GUSTING TO 30 KTS ACROSS THE NORTH CENTRAL AND JAMES RIVER VALLEY WILL CONTINUE...DUE IN LARGE PART TO NEAR 15 MB/6 HR PRESSURE FALLS AHEAD OF THE WARM FRONT ACROSS EASTERN MONTANA. SOUTHWEST WINDS TO 30 KTS ARE EXPECTED AFTER 10 UTC ACROSS THE SOUTHWEST IN THE WAKE OF THE WARM FRONT...WITH BLOWING SNOW A THREAT UNTIL SURFACE TEMPERATURES WARM INTO THE MID 30S BY MID MORNING. UPDATE ISSUED AT 956 PM CST THU JAN 2 2014 ANOTHER QUICK UPDATE TO CLEAN UP POPS ACROSS CENTRAL NORTH DAKOTA. LIGHT SNOW IS TAPERING OFF IN BISMARCK WITH 0.5 INCH ACCUMULATION AT THE OFFICE. EXPECT LIGHT SNOW TO CONTINUE TO TAPER FROM WEST TO EAST THROUGH THE REST OF THE EVENING. NEXT ROUND OF PRECIPITATION IS EXPECTED TO MOVE INTO THE NORTH LATE TONIGHT AND CURRENT FORECAST LOOKS REASONABLE HERE SO NO CHANGES. WILL UPDATE ALL PRODUCTS SHORTLY. UPDATE ISSUED AT 827 PM CST THU JAN 2 2014 WARM ADVECTION SNOW IS MORE ROBUST THAN INITIALLY THOUGHT ACROSS CENTRAL NORTH DAKOTA. WILL UPDATE FLURRIES TO LIKELY TO CATEGORICAL LIGHT SNOW THIS EVENING...MAINLY ALONG AND EAST OF HIGHWAY 83. TWO TENTHS OF AN INCH OF LIGHT FLUFFY SNOW AT KBIS SO FAR. THINK AMOUNTS WILL BE A HALF INCH OR LESS IN MOST AREAS. WITH HIGHER SLR RATIOS IN THE EASTERN CWA...CANNOT RULE OUT SOME REPORTS OF UP TO AN INCH FROM BOTTINEAU...RUGBY AREAS DOWN THROUGH HARVEY AND CARRINGTON. UPDATED ZONES HAVE BEEN SENT. UPDATE ISSUED AT 654 PM CST THU JAN 2 2014 LATEST RADAR LOOP IS INDICATING LIGHT WARM ADVECTION SNOW ACROSS CENTRAL NORTH DAKOTA. LATEST RAP MESOSCALE MODEL DEPICTS LIGHT REFLECTIVITIES TRACKING EAST ACROSS CENTRAL NORTH DAKOTA THIS EVENING. FOR NOW WILL ADD A MENTION OF SCATTERED FLURRIES MAINLY ALONG AND EAST OF THE HIGHWAY 83 CORRIDOR THROUGH THE EVENING. OTHERWISE NO SIGNIFICANT CHANGES TO THE GOING FORECAST. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY) ISSUED AT 259 PM CST THU JAN 2 2014 THE MAIN FORECAST ISSUE IS POTENTIAL BLIZZARD CONDITIONS DEVELOPING FRIDAY AFTERNOON ACROSS THE NORTH. IN THE NEAR TERM...HAVE EXPANDED AREA OF ISOLATED FLURRIES NORTH AND WEST...AND CONTINUED FLURRIES LATER INTO THE EVENING IN THE TURTLE MOUNTAIN AREA. WIND CHILL VALUES WILL BE BORDERLINE ADVISORY CRITERIA THROUGH THIS EVENING FROM THE TURTLE MOUNTAINS INTO THE JAMES RIVER VALLEY...BUT WILL COVER IN HAZARDOUS WEATHER OUTLOOK IN ORDER TO AVOID CONFUSION FROM MULTIPLE HEADLINES. 12Z GFS/ECMWF ARE IN AGREEMENT WITH A STRONGER SURFACE GRADIENT AND POTENTIAL FOR WIND GUSTS AROUND 40 MPH BEGINNING FRIDAY AFTERNOON IN THE NORTH. THE NAM IS LESS ROBUST WITH WIND SPEEDS. HOWEVER...COMPARING MODELS DURING THE RECENT BLIZZARD EVENT WITH THE FRIDAY STORM...ALONG WITH CONSIDERATIONS OF THE FRESH SNOW COVER...THE BALANCE TILTS TOWARD A BLIZZARD WATCH. STRONG WINDS WILL LIKELY BE ABLE TO BREAK THROUGH ANY CRUST THAT DEVELOPS ON THE LOOSE SNOW DURING THE WARM-UP FRIDAY. HAVE COVERED THE ENTIRE FORECAST AREA IN THE WATCH. SNOWFALL AMOUNTS WILL BE AN INCH OR TWO ACROSS THE NORTH...LESS THAN AN INCH CENTRAL AND SOUTH. THERE IS POTENTIAL FOR SOME SLEET AND/OR FREEZING RAIN...BUT THE MAIN TRAVEL HAZARD WILL BE BLOWING AND DRIFTING SNOW. .LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY) ISSUED AT 259 PM CST THU JAN 2 2014 ACTIVE WEATHER IN TERMS OF A BLIZZARD WATCH ONGOING FROM FRIDAY EVENING THROUGH SATURDAY MORNING...FOLLOWED BY LIFE THREATENING WIND CHILL TEMPERATURES BETWEEN 50 AND 60 BELOW SATURDAY NIGHT THROUGH TUESDAY MORNING. A STRONG ARCTIC FRONT WILL SWEEP TO THE SOUTHERN BORDER BY 00Z SATURDAY WITH A SHARP TRANSITION TO NORTHWEST WINDS AND POSSIBLY ONGOING BLIZZARD CONDITIONS WITH VISIBILITIES LESS THAN ONE QUARTER MILE. THE WINDS WILL BEGIN TO ABATE SATURDAY MORNING BUT REMAIN BRISK AT 10 TO 20 MPH THROUGH SATURDAY NIGHT. BRUTAL H85 TEMPS OF -35C TO -37C ACROSS WESTERN AND CENTRAL NORTH DAKOTA WILL ARRIVE SUNDAY INTO MONDAY MORNING. ALONG WITH THAT WILL BE NORTHWEST SURFACE WINDS OF 20 TO 30 MPH ASSOCIATED WITH THE COLDEST CHUNK OF AIR. THAT WOULD PUT THE RISK OF FROSTBITE AND HYPOTHERMIA POSSIBILITIES TO WITHIN 5 MINUTES OR LESS ON EXPOSED SKIN SURFACES. A WIND CHILL WARNING HEADLINE WILL LIKELY BE HOISTED BY FRIDAY AFTERNOON. NO SIGNIFICANT SNOWSTORMS DURING THE EXTREME COLD SNAP. TEMPERATURES MODERATE BY WEDNESDAY AND THURSDAY...FROM WEST TO EAST...WITH HIGHS 15 TO 25 ABOVE ON THURSDAY. HIGHS SATURDAY WILL RANGE FROM 15 BELOW IN THE TURTLE MOUNTAINS TO 8 ABOVE IN THE SOUTHWEST. THE COLDEST AIR WILL ARRIVE SUNDAY THROUGH MONDAY NIGHT WITH LOWS 15 BELOW TO 30 BELOW...AND HIGHS 15 BELOW TO 25 BELOW ZERO. THESE TEMPERATURES WHEN COMBINED WITH WINDS OF 20 TO 30 MPH WILL YIELD WIND CHILL TEMPERATURES OF 50 TO 60 BELOW. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 102 AM CST FRI JAN 3 2014 IFR STRATUS WITH LIGHT SNOW IS EXPECTED TO CONTINUE TO IMPACT KBIS AND KJMS THROUGH AT LEAST 10 UTC. STRONG SOUTHERLY WINDS TO 30 KTS TONIGHT AT KJMS WILL ALSO RESULT IN BLOWING SNOW. A STRONG STORM SYSTEM WILL IMPACT WESTERN AND CENTRAL NORTH DAKOTA FRIDAY AFTERNOON INTO SATURDAY MORNING. WIDESPREAD LIFR CONDITIONS WILL DEVELOP WITH NORTHWEST WINDS TO 45KTS...LIGHT SNOW AND BLOWING SNOW. && .BIS WATCHES/WARNINGS/ADVISORIES... BLIZZARD WATCH FROM THIS EVENING THROUGH SATURDAY MORNING FOR NDZ018>023-025-031>037-040>048-050-051. BLIZZARD WATCH FROM THIS AFTERNOON THROUGH SATURDAY MORNING FOR NDZ001>005-009>013-017. && $$ UPDATE...AYD SHORT TERM...RP KINNEY LONG TERM...KS AVIATION...AYD
AREA FORECAST DISCUSSION
NWS GRAND FORKS ND
1154 PM CST THU JAN 2 2014 .UPDATE... ISSUED AT 1153 PM CST THU JAN 2 2014 MADE A FEW MINOR TWEAKS TO POPS TO REFLECT CURRENT TRENDS...SNOW HAS BEEN MORE HIT AND MISS BUT BLOWING SNOW HAS STARTED GOING ACROSS THE VALLEY. TEMPS WILL CONTINUE TO SLOWLY RISE OVERNIGHT AS SOUTHERLY WINDS AND WARM AIR ADVECTION CONTINUES. UPDATE ISSUED AT 937 PM CST THU JAN 2 2014 GIVEN RADAR RETURNS FROM MINOT AND SFC OBS OVER THE NORTH CENTRAL PORTION OF ND...BUMPED UP POPS FOR THE REST OF THE EVENING INTO THE PERIOD JUST AFTER MIDNIGHT. THE RAP AND NAM SEEM TO DO FAIRLY WELL WITH THE GOING TRENDS...AND HAVE SOME PRECIP ALONG THE LEADING EDGE OF THE WARM AIR ADVECTION. KEPT LIKELY POPS OVER THE DEVILS LAKE BASIN DURING THE NEXT FEW HOURS...BUT TRANSITIONED TO SLIGHTLY LOWER POPS LATER TONIGHT AS THE BAND MOVES EAST AS THE MODELS AND RADAR TRENDS SHOW SOME WEAKENING. ANY ACCUMULATIONS WILL BE VERY LIGHT. BLOWING SNOW MAY ALSO BE AN ISSUE...BUT NOT SURE HOW WIDESPREAD IT WILL BE. WILL KEEP AN EYE ON WEB CAM TRENDS FOR NOW AND WILL KEEP HEADLINES AS THEY ARE. UPDATE ISSUED AT 644 PM CST THU JAN 2 2014 THROUGH IN A FLURRY MENTION AFTER 03Z AS THERE HAVE BEEN SOME SNOW REPORTS IN NORTH CENTRAL ND AND THE RAP AND NAM SHOW SOME WEAK QPF MOVING THROUGH THE DEVILS LAKE BASIN. THINK THAT ANYTHING SIGNIFICANT WILL HOLD OFF UNTIL AFTER MIDNIGHT SO DID NOT MAKE ANY CHANGES TO POPS FOR NOW. THE REST OF THE CWA SHOULD SEE INCREASING CLOUDS THROUGH THIS EVENING AND EVENTUALLY RISING TEMPS...ALTHOUGH THE EASTERN COUNTIES MAY BE STEADY FOR A WHILE UNTIL THE STRONGER WARM AIR ADVECTION KICKS IN. && .SHORT TERM...(THIS EVENING THROUGH FRIDAY NIGHT) ISSUED AT 225 PM CST THU JAN 2 2014 THE MAIN CHALLENGE WILL BE LIFE THREATENING WIND CHILLS AND POTENTIAL BLIZZARD LATE FRIDAY AFTERNOON INTO SATURDAY MORNING. MODELS ARE IN GOOD AGREEMENT AND PREFER THE CONSISTENT GFS/ECMWF MIX THIS AFTERNOON. FOR TONIGHT...SOUTHERLY WINDS WILL INCREASE AND THERE WILL BE DANGEROUS WIND CHILLS TO 35 BELOW IN ALL AREAS. THERE WILL ALSO BE 30KT TO MIX FROM THE SOUTH IN THE VALLEY...AND BLOWING SNOW IS LIKELY WITH VSBYS DOWN TO ONE MILE AT TIMES IN OPEN COUNTRY. TEMPS WILL SLOWLY RISE WITH THE SOUTH WINDS. THERE COULD BE SOME LIGHT SNOW IN THE FAR NORTH LATE...BUT MINIMAL ACCUMULATION EXPECTED. ON FRIDAY/FRI NIGHT...SFC LOW PRESSURE WILL MOVE INTO THE CENTRAL VALLEY BY 00Z. EXPECT A PERIOD OF MIXED PRECIP IN THE WARM SECTOR...WITH SNOW IN THE FAR NORTH BY LATE AFTERNOON. WINDS WILL SHIFT TO THE NORTH AND INCREASE IN THE FAR N/NW AFTER 21Z...WITH POTENTIAL BLIZZARD CONDITIONS DEVELOPING AND MOVING SOUTH THROUGH FRIDAY EVENING AND OVERNIGHT. THERE WILL BE ABOUT 40-45KT TO MIX FROM 880MB PER THE GFS/ECMWF...WITH THE NAM A BIT WEAKER WITH THE MIXED LAYER. GIVEN THAT THERE WILL BE FALLING SNOW...AND BLOWING SNOW ADVECTING SOUTH...BLIZZARD CONDITIONS MAY DEVELOP IN THE NORTHERN VALLEY AFTER 21Z FRI...MOVING INTO THE GFK AREA BY 2Z OR SO THEN TO FARGO AFTER 3Z. FOR SIMPLICITY SAKE...WILL START THE BLIZZARD WATCH IN THE NORTH AT 21Z FRI THEN POINTS SOUTH AT 00Z SAT IN CASE FRONT SPEEDS UP A BIT. .LONG TERM...(SATURDAY THROUGH THURSDAY) ISSUED AT 225 PM CST THU JAN 2 2014 FOR SATURDAY...WINDS WILL REMAIN STRONG DURING THE MORNING WITH 30-35KT TO MIX UNTIL 18Z SAT. THEREFORE...BLOWING SNOW WILL REMAIN A PROBLEM IN THE VALLEY WITH LIKELY FALLING TEMPS BELOW ZERO IN ALL AREAS ON SATURDAY. FOR SAT NIGHT/SUN...CONTINUED INTENSE COLD AIR ADVECTION WILL CONTINUE WITH 925MB TEMPS FALLING TO -35C BY SUNDAY EVENING. COUPLE THIS WITH TEMPS WELL BELOW ZERO AND 10-25MPH WINDS...LIFE THREATENING WIND CHILLS TO 60 BELOW ARE POSSIBLE. THIS WILL BE A DANGEROUS ARCTIC OUTBREAK GIVEN THE COMBINATION OF WIND CHILLS...SOME FLURRIES POSSIBLE ON SUNDAY WITH AREAS OF BLOWING/DRIFTING. CAUTION IS URGED BY ANYONE VENTURING OUTDOORS DURING THIS TIMEFRAME. FOR MON-THU...THE LONG TERM WILL START OUT WITH A NORTHERLY FLOW PATTERN ALOFT CONTINUING TO HOLD A FRIGID ARCTIC AIR MASS IN PLACE...BRINGING WELL BELOW AVG TEMPS TO THE AREA EARLY IN THE WEEK. AN UPPER WAVE DROPS INTO THE DAKOTAS TUE NIGHT INTO WED...HOWEVER APPEARS ANY SNOW WILL BE ACROSS CNTRL AND WRN ND WITH THE SFC HIGH MOVING ACROSS THE VALLEY. AN H500 SHORT WAVE RIDGE THEN CONTINUES THE DRY WEATHER FROM WED TO THE END OF THE WEEK...WITH RETURN FLOW SETTING UP TO BRING MUCH WELCOMED RELIEF TO THE FRIGID AIRMASS. TEMPS IN THE TEENS ARE POSSIBLE BY THURSDAY. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z FRIDAY NIGHT) ISSUED AT 1153 PM CST THU JAN 2 2014 SOME BLOWING SNOW HAS REDUCED VIS AND BROUGHT SOME LOWER CIGS FROM THE RED RIVER VALLEY WESTWARD OVERNIGHT...THINK THAT THIS WILL CONTINUE ON AND OFF INTO THE EARLY MORNING HOURS AS SOUTHERLY WINDS CONTINUE TO BE BREEZY. THINK THAT CONDITIONS WILL GO IN AND OUT OF MVFR TO VFR WITH SOME DROPS TO IFR...AND COVERED THIS WITH TEMPO GROUPS. THE CENTER OF THE SFC LOW WILL MOVE INTO THE REGION BY TOMORROW AFTERNOON...BRINGING SOME DECREASING SOUTHWESTERLY WINDS FOR A WHILE BUT LIGHT SNOW AND POSSIBLY EVEN SOME FZRA IN THE SOUTH WILL CONTINUE. THE COLD FRONT WILL DROP DOWN INTO THE AREA FRIDAY EVENING...WITH STRONG NORTHWESTERLY WINDS AND BLOWING SNOW REDUCING VIS DOWN TO A MILE OR POSSIBLY LESS. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...BLIZZARD WATCH FROM FRIDAY EVENING THROUGH SATURDAY MORNING FOR NDZ024-026>030-038-039-049-052-053. WIND CHILL ADVISORY UNTIL 6 AM CST FRIDAY FOR NDZ006>008-014>016- 024-026>030-038-039-049-052>054. BLIZZARD WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR NDZ006>008-014>016-054. MN...BLIZZARD WATCH FROM FRIDAY EVENING THROUGH SATURDAY MORNING FOR MNZ001>003-027-029-030-040. WIND CHILL ADVISORY UNTIL 6 AM CST FRIDAY FOR MNZ001>009-013>017- 022>024-027>032-040. BLIZZARD WATCH FROM FRIDAY AFTERNOON THROUGH SATURDAY MORNING FOR MNZ004-007. && $$ UPDATE...JR SHORT TERM...DK LONG TERM...DK/SPEICHER AVIATION...JR
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
928 PM CST SAT JAN 4 2014 .UPDATE... ...VERY COLD THE NEXT SEVERAL DAYS... THE COLD FRONT CONTINUES TO MAKE GOOD PROGRESS TONIGHT MOVING SOUTHEAST. AT 9 PM...IT WAS LOCATED GENERALLY ALONG AN EAST OF SHERMAN TO FORT WORTH AND EASTLAND LINE WITH MUCH STRONGER NORTHWEST WINDS LAGGING SEVERAL HOURS BEHIND THE INITIAL WIND SHIFT. EXPECT TEMPERATURES TO DROP UP TO 10 DEGREES IN THE FIRST HOUR BEHIND THE INITIAL WIND SHIFT...THEN CONTINUING TO DROP THROUGHOUT THE REST OF THE NIGHT. ONE CONCERN WITH THIS VERY COLD AIR MASS WILL BE THE WIND CHILLS THAT WILL OCCUR SUNDAY MORNING...AND AGAIN SUNDAY NIGHT THROUGH MONDAY MORNING. READINGS BELOW 10 DEGREES WILL BE LIKELY WEST THROUGH NORTH OF THE METROPLEX SUNDAY MORNING AND GENERALLY ACROSS ALL OF NORTH AND CENTRAL TEXAS FROM MIDNIGHT SUNDAY THROUGH MID MORNING MONDAY. THOSE VENTURING OUT IN THESE CONDITIONS SHOULD DRESS APPROPRIATELY AND LIMIT OUTSIDE EXPOSURE TIME. IN OUR EVENING ANALYSIS OF MODEL DATA...WE/VE DECIDED TO LOWER LOW TEMPS A DEGREE OR TWO ON MONDAY...LOWERED HIGHS ON MONDAY A GOOD 3-4 DEGREES AND MADE MINOR ADJUSTMENTS TO THE LOWS ON TUESDAY MORNING. HAVE ALSO MADE SOME HOURLY GRID ADJUSTMENTS TO BETTER REFLECT FRONTAL TIMING AND TRENDS OF WINDS/TEMPS/DEWPOINTS BEHIND THE FRONT. NEW FORECAST PACKAGE WILL BE OUT SHORTLY. 75 && .AVIATION... /00Z TAFS/ MAIN CONCERNS CONTINUE TO BEING TIMING OF THE ARCTIC FRONT INTO ALL THE TERMINALS...THE SUBSEQUENT POST-FRONTAL CIGS. COLD FRONT NOW PUSHING THROUGH AN OKC-WICHITA FALLS-LUBBOCK LINE WITH THE INITIAL SURGE RELATIVELY SHALLOW AND JUST 2-2.5 KFT PER MODEL BUFR AND RUC SOUNDINGS...AND MOS GUIDANCE. THE TRENDS BY MODELS HAS BEEN TO SLOW THE INITIAL SURGE...LIKELY DUE TO STRONG HEIGHT FALLS ASSOCIATED WITH A SHORTWAVE DROPPING SOUTHEAST OVER WESTERN HIGH PLAINS. DID SLOW THE FROPA A FEW HOURS...BUT NOTHING TOWARD THE VERY SLOW NAM AS DENSE AIR MASSES LIKE THESE USUALLY PICK UP SPEED AT NIGHTFALL IN THE WINTER...NOT SLOW DOWN DESPITE AFOREMENTIONED HEIGHT FALLS. DFW AIRPORTS: WILL HAVE FROPA AT ALLIANCE AROUND 04Z/10 PM...DFW/FTW 05Z/11 PM...AND LOVE FIELD/ARLINGTON 06Z/MIDNIGHT. SSW WINDS 10-15 MPH MAY BRIEFLY VEER WSW AND DIMINISH TO AROUND 10 KTS AROUND 03Z...BEFORE SHIFTING NW AROUND 15 KTS. ONCE THE STRONG CAA CATCHES UP...PRESSURE GRADIENT AND FRONTAL INVERSION DEPTH INCREASE WITH GUSTY NNW WINDS 18-23 KTS THROUGH THE MORNING HOURS. MVFR CIGS TO PREVAIL ABOVE 020...THEN SLOWLY RISE INTO VFR 030-040 BY MIDDAY AND SCATTER OUT WITH WIND SPEEDS SLOWLY DROPPING BY EARLY TO MID AFTERNOON SUNDAY. WACO: FROPA WITH NW WINDS 15 KTS AROUND 09Z/3 AM...THEN THE SAME PROCESS WITH INCREASING AND GUSTY NNW WINDS 17-21 KTS WITH MVFR CIGS ABOVE 020 INITIALLY...GOING VFR 030-040 BY MIDDAY...THEN SCATTERING LATER ON SUNDAY AFTERNOON. 05/ && .PREV DISCUSSION... /ISSUED 458 PM CST SAT JAN 4 2014/ AN ARCTIC COLD FRONT WILL MOVE THROUGH ALL OF NORTH TEXAS TONIGHT AND BRING SOME VERY ABRUPT CHANGES. THE PASSAGE OF THE FRONT WILL TURN THE WIND TO THE NORTH/NORTHWEST AND INCREASE IT BETWEEN 15 AND 25 MPH ALONG WITH SOME GUSTS IN EXCESS OF 30 MPH. THE STRONGEST WIND SPEEDS SHOULD LAG THE FRONT BY A FEW HOURS. SINCE THE FRONT WILL MOVE THROUGH MOST LOCATIONS AFTER DARK...THE COMBINATION OF NOCTURNAL COOLING AND COLD AIR ADVECTION WILL RESULT IN QUICKLY FALLING TEMPERATURES BEHIND THE FRONT. OVERNIGHT LOW TEMPERATURES WILL FALL BELOW FREEZING IN MOST LOCATIONS WITH WIND CHILL READINGS IN THE SINGLE DIGITS AND TEENS ACROSS THE NORTHWEST HALF OF THE REGION. THERE IS A SLIGHT CHANCE OF RAIN ACROSS THE EASTERN ZONES TONIGHT NEAR AND BEHIND THE FRONT. SINCE MOISTURE WILL BE LIMITED...ANY RAIN THAT FALLS SHOULD BE VERY LIGHT. HOWEVER...SOME LOCATIONS THAT SEE LIGHT RAIN WILL FALL BELOW FREEZING BEFORE SUNRISE. THEREFORE...BRIEF...LIGHT FREEZING RAIN WILL BE POSSIBLE. IF ANY FREEZING RAIN DOES OCCUR IN THE EASTERN ZONES...IMPACTS SHOULD BE MINIMAL SINCE PRECIP WILL BE VERY LIGHT. ALL PRECIP SHOULD MOVE EAST OF NORTH TEXAS AFTER SUNRISE SUNDAY AS THE UPPER TROUGH AXIS EXITS THE REGION. EVEN THOUGH THE SUN WILL RETURN ON SUNDAY...IT WILL BE A COLD AND BLUSTERY DAY WITH HIGH TEMPERATURES ONLY REACHING THE 30S TO LOWER 40S AND A NORTH TO NORTHWEST WIND BETWEEN 15 AND 25 MPH ALONG WITH SOME HIGHER GUSTS. SURFACE HIGH PRESSURE WILL SETTLE OVER THE STATE SUNDAY NIGHT THROUGH MONDAY AND RESULT IN DECREASING WIND SPEEDS AND A MOSTLY CLEAR SKY. SINCE THE WIND WILL NOT BECOME CALM SUNDAY NIGHT...RADIATIONAL COOLING WILL NOT BE OPTIMAL. HOWEVER...OVERNIGHT LOWS SUNDAY SHOULD STILL FALL INTO THE TEENS AND 20S WITH WIND CHILL READINGS GENERALLY IN THE SINGLE DIGITS. MONDAY AND MONDAY NIGHT WILL ALSO BE COLD WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE TEENS TO AROUND 20. THE ONLY SAVING GRACE WILL BE A RELATIVELY LIGHT WIND. A WARM UP WILL BEGIN ON TUESDAY AS SOUTHERLY WINDS RETURN IN RESPONSE TO A DEVELOPING HIGH PLAINS SURFACE TROUGH. LOW LEVEL MOISTURE WILL SURGE NORTHWARD TUESDAY NIGHT THROUGH WEDNESDAY AS THE SURFACE TROUGH DEEPENS INTO THE SOUTHERN HIGH PLAINS. RAIN CHANCES WILL BEGIN WEDNESDAY MORNING AS LARGE SCALE LIFT INCREASES WITH THE APPROACH OF A SHORT WAVE TROUGH. THE BEST RAIN CHANCES WILL BE ACROSS THE EASTERN ZONES WEDNESDAY NIGHT THROUGH THURSDAY WHEN A WEAK COLD FRONT ENTERS THE REGION. RAIN CHANCES SHOULD CONTINUE ACROSS NORTH TEXAS THURSDAY NIGHT THROUGH FRIDAY AS AN UPPER TROUGH MOVES ACROSS THE STATE. THE ECMWF AND GFS SOLUTIONS ARE STILL NOT IN AGREEMENT ON THE STRENGTH OF THIS SYSTEM. FOR NOW...WE WILL SIDE WITH THE MORE PROGRESSIVE GFS SOLUTION AND MOVE THE TROUGH AXIS THROUGH NORTH TEXAS SATURDAY. HOWEVER...IF THE ECMWF SOLUTION VERIFIES IT WOULD RESULT IN AN EXTENDED PERIOD OF RAIN THROUGH SUNDAY OF NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 28 37 17 30 21 / 10 10 0 0 0 WACO, TX 32 45 19 36 15 / 10 10 0 0 0 PARIS, TX 27 35 12 26 13 / 20 10 5 0 0 DENTON, TX 24 35 14 29 16 / 10 10 0 0 0 MCKINNEY, TX 27 35 14 27 16 / 10 10 0 0 0 DALLAS, TX 28 37 17 30 20 / 10 10 0 0 0 TERRELL, TX 29 37 15 30 16 / 20 10 0 0 0 CORSICANA, TX 32 39 19 32 18 / 10 10 5 0 0 TEMPLE, TX 31 43 19 37 16 / 5 10 0 0 0 MINERAL WELLS, TX 21 37 14 31 16 / 5 10 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ /75
AREA FORECAST DISCUSSION...UPDATED
NWS FORT WORTH TX
551 PM CST SAT JAN 4 2014 .AVIATION... /00Z TAFS/ MAIN CONCERNS CONTINUE TO BEING TIMING OF THE ARCTIC FRONT INTO ALL THE TERMINALS...THE SUBSEQUENT POST-FRONTAL CIGS. COLD FRONT NOW PUSHING THROUGH AN OKC-WICHITA FALLS-LUBBOCK LINE WITH THE INITIAL SURGE RELATIVELY SHALLOW AND JUST 2-2.5 KFT PER MODEL BUFR AND RUC SOUNDINGS...AND MOS GUIDANCES. THE TRENDS BY MODELS HAS BEEN TO SLOW THE INITIAL SURGE...LIKELY DUE TO STRONG HEIGHT FALLS ASSOCIATED WITH A SHORTWAVE DROPPING SOUTHEAST OVER WESTERN HIGH PLAINS. DID SLOW THE FROPA A FEW HOURS...BUT NOTHING TOWARD THE VERY SLOW NAM AS DENSE AIRMASSES LIKE THESE USUALLY PICK UP SPEED AT NIGHTFALL IN THE WINTER...NOT SLOW DOWN DESPITE AFOREMENTIONED HEIGHT FALLS. DFW AIRPORTS: WILL HAVE FROPA AT ALLIANCE AROUND 04Z/10 PM...DFW/FTW 05Z/11 PM...AND LOVE FIELD/ARLINGTON 06Z/MIDNIGHT. SSW WINDS 10-15 MPH MAY BRIEFLY VEER WSW AND DIMINISH TO AROUND 10 KTS AROUND 03Z...BEFORE SHIFTING NW AROUND 15 KTS. ONCE THE STRONG CAA CATCHES UP...PRESSURE GRADIENT AND FRONTAL INVERSION DEPTH INCREASE WITH GUSTY NNW WINDS 18-23 KTS THROUGH THE MORNING HOURS. MVFR CIGS TO PREVAIL ABOVE 020...THEN SLOWLY RISE INTO VFR 030-040 BY MIDDAY AND SCATTER OUT WITH WIND SPEEDS SLOWLY DROPPING BY EARLY TO MID AFTERNOON SUNDAY. WACO: FROPA WITH NW WINDS 15 KTS AROUND 09Z/3 AM...THEN THE SAME PROCESS WITH INCREASING AND GUSTY NNW WINDS 17-21 KTS WITH MVFR CIGS ABOVE 020 INITIALLY...GOING VFR 030-040 BY MIDDAY...THEN SCATTERING LATER ON SUNDAY AFTERNOON. 05/ && .PREV DISCUSSION... /ISSUED 458 PM CST SAT JAN 4 2014/ AN ARCTIC COLD FRONT WILL MOVE THROUGH ALL OF NORTH TEXAS TONIGHT AND BRING SOME VERY ABRUPT CHANGES. THE PASSAGE OF THE FRONT WILL TURN THE WIND TO THE NORTH/NORTHWEST AND INCREASE IT BETWEEN 15 AND 25 MPH ALONG WITH SOME GUSTS IN EXCESS OF 30 MPH. THE STRONGEST WIND SPEEDS SHOULD LAG THE FRONT BY A FEW HOURS. SINCE THE FRONT WILL MOVE THROUGH MOST LOCATIONS AFTER DARK...THE COMBINATION OF NOCTURNAL COOLING AND COLD AIR ADVECTION WILL RESULT IN QUICKLY FALLING TEMPERATURES BEHIND THE FRONT. OVERNIGHT LOW TEMPERATURES WILL FALL BELOW FREEZING IN MOST LOCATIONS WITH WIND CHILL READINGS IN THE SINGLE DIGITS AND TEENS ACROSS THE NORTHWEST HALF OF THE REGION. THERE IS A SLIGHT CHANCE OF RAIN ACROSS THE EASTERN ZONES TONIGHT NEAR AND BEHIND THE FRONT. SINCE MOISTURE WILL BE LIMITED...ANY RAIN THAT FALLS SHOULD BE VERY LIGHT. HOWEVER...SOME LOCATIONS THAT SEE LIGHT RAIN WILL FALL BELOW FREEZING BEFORE SUNRISE. THEREFORE...BRIEF...LIGHT FREEZING RAIN WILL BE POSSIBLE. IF ANY FREEZING RAIN DOES OCCUR IN THE EASTERN ZONES...IMPACTS SHOULD BE MINIMAL SINCE PRECIP WILL BE VERY LIGHT. ALL PRECIP SHOULD MOVE EAST OF NORTH TEXAS AFTER SUNRISE SUNDAY AS THE UPPER TROUGH AXIS EXITS THE REGION. EVEN THOUGH THE SUN WILL RETURN ON SUNDAY...IT WILL BE A COLD AND BLUSTERY DAY WITH HIGH TEMPERATURES ONLY REACHING THE 30S TO LOWER 40S AND A NORTH TO NORTHWEST WIND BETWEEN 15 AND 25 MPH ALONG WITH SOME HIGHER GUSTS. SURFACE HIGH PRESSURE WILL SETTLE OVER THE STATE SUNDAY NIGHT THROUGH MONDAY AND RESULT IN DECREASING WIND SPEEDS AND A MOSTLY CLEAR SKY. SINCE THE WIND WILL NOT BECOME CALM SUNDAY NIGHT...RADIATIONAL COOLING WILL NOT BE OPTIMAL. HOWEVER...OVERNIGHT LOWS SUNDAY SHOULD STILL FALL INTO THE TEENS AND 20S WITH WIND CHILL READINGS GENERALLY IN THE SINGLE DIGITS. MONDAY AND MONDAY NIGHT WILL ALSO BE COLD WITH HIGHS GENERALLY IN THE 30S AND LOWS IN THE TEENS TO AROUND 20. THE ONLY SAVING GRACE WILL BE A RELATIVELY LIGHT WIND. A WARM UP WILL BEGIN ON TUESDAY AS SOUTHERLY WINDS RETURN IN RESPONSE TO A DEVELOPING HIGH PLAINS SURFACE TROUGH. LOW LEVEL MOISTURE WILL SURGE NORTHWARD TUESDAY NIGHT THROUGH WEDNESDAY AS THE SURFACE TROUGH DEEPENS INTO THE SOUTHERN HIGH PLAINS. RAIN CHANCES WILL BEGIN WEDNESDAY MORNING AS LARGE SCALE LIFT INCREASES WITH THE APPROACH OF A SHORT WAVE TROUGH. THE BEST RAIN CHANCES WILL BE ACROSS THE EASTERN ZONES WEDNESDAY NIGHT THROUGH THURSDAY WHEN A WEAK COLD FRONT ENTERS THE REGION. RAIN CHANCES SHOULD CONTINUE ACROSS NORTH TEXAS THURSDAY NIGHT THROUGH FRIDAY AS AN UPPER TROUGH MOVES ACROSS THE STATE. THE ECMWF AND GFS SOLUTIONS ARE STILL NOT IN AGREEMENT ON THE STRENGTH OF THIS SYSTEM. FOR NOW...WE WILL SIDE WITH THE MORE PROGRESSIVE GFS SOLUTION AND MOVE THE TROUGH AXIS THROUGH NORTH TEXAS SATURDAY. HOWEVER...IF THE ECMWF SOLUTION VERIFIES IT WOULD RESULT IN AN EXTENDED PERIOD OF RAIN THROUGH SUNDAY OF NEXT WEEK. 79 && .PRELIMINARY POINT TEMPS/POPS... DALLAS-FT. WORTH, TX 28 37 18 33 21 / 10 10 0 0 0 WACO, TX 32 45 21 39 15 / 10 10 0 0 0 PARIS, TX 27 35 13 29 13 / 20 10 5 0 0 DENTON, TX 24 35 17 28 15 / 10 10 0 0 0 MCKINNEY, TX 27 35 15 29 16 / 10 10 0 0 0 DALLAS, TX 28 37 18 32 20 / 10 10 0 0 0 TERRELL, TX 29 37 16 32 16 / 20 10 0 0 0 CORSICANA, TX 32 39 20 36 18 / 10 10 5 0 0 TEMPLE, TX 31 43 20 39 16 / 5 10 0 0 0 MINERAL WELLS, TX 21 37 15 33 16 / 5 10 0 0 0 && .FWD WATCHES/WARNINGS/ADVISORIES... NONE. && $$ 05/79
AREA FORECAST DISCUSSION
NWS MILWAUKEE/SULLIVAN WI
926 PM CST SAT JAN 4 2014 .UPDATE... NO SURPRISES IN THE 00Z NAM. THEY CONFIRM THE 6 HOUR SLOWER ARRIVAL OF WIND CHILLS REACHING ADVISORY CRITERIA. BESIDES THAT THE NAM TEMPS AND NAM MOS HAVE VIRTUALLY THE SAME BITTER COLD TEMPERATURES SUNDAY NIGHT THROUGH MONDAY. THEREFORE THE WIND CHILL WARNINGS REMAIN WITH THE SAME WIND CHILL VALUES. THE 00Z NAM STILL CLIPS THE KENOSHA AREA WITH 3 TO 5 INCH SNOW POTENTIAL LATE TONIGHT THROUGH SUNDAY. WILL BE A CLOSE CALL ON THE NORTH FRINGE OF THE PRECIPITATION SHEILD. AMOUNTS RAPIDLY DECREASE TO THE NORTH WITH UP TO AN INCH POSSIBLE IN THE FAR SOUTHEAST CORNER OF MILWAUKEE COUNTY. && .AVIATION/06Z TAFS/... THE SNOW HAS TEMPORARILY SAGGED SOUTH OF THE KENOSHA AREA. THE 00Z NAM STILL CLIPS THE KENOSHA AREA WITH 3 TO 5 INCH SNOW POTENTIAL LATE TONIGHT THROUGH SUNDAY. WILL BE A CLOSE CALL ON THE NORTH FRINGE OF THE PRECIPITATION SHEILD. AMOUNTS RAPIDLY DECREASE TO THE NORTH WITH UP TO AN INCH POSSIBLE IN THE FAR SOUTHEAST CORNER OF MILWAUKEE COUNTY. THEREFORE IFR VSBYS AGAIN EXPECTED IN THE FAR SOUTHEAST. OTHERWISE MVFR CIGS IN THE SOUTHEAST WITH VFR FARTHER NORTH AND WEST. NORTHWEST WINDS WILL INCREASE SUNDAY AS BITTER COLD AIR MOVES IN BY SUNDAY NIGHT AND CONTINUING INTO TUESDAY. && .PREV DISCUSSION... /ISSUED 331 PM CST SAT JAN 4 2014/ TONIGHT AND SUNDAY...FORECAST CONFIDENCE IS HIGH. WINTER WEATHER ADVISORY FOR WALWORTH...RACINE AND KENOSHA COUNTIES CONTINUES UNTIL 00Z MONDAY. AREA RADARS SHOWING MORE BANDS OF LIGHT TO MODERATE SNOW DEVELOPING FROM FAR EASTERN IOWA...THROUGH NORTHEAST ILLINOIS/FAR SOUTHEAST WISCONSIN...INTO SOUTHWEST LOWER MICHIGAN. THIS WAS BEING DRIVEN BY RIGHT ENTRANCE REGION OF 300 MB JET STREAK...AS WELL AS MODEST LOW TO MID LEVEL FRONTOGENESIS RESPONSE. THE MID LEVEL FRONTOGENESIS LINGERS ACROSS THE FAR SOUTHEAST INTO SUNDAY AFTERNOON...WITH 850MB TROUGH/CONVERGENCE AND LOW LEVEL FRONTOGENESIS RESPONSE ALSO LINGERING INTO TONIGHT. GOOD UPWARD VERTICAL MOTION SHOWN IN SATURATED AIR COLUMN AND DENDRITE ZONE ACROSS THE FAR SOUTHEAST COUNTIES THROUGH TONIGHT AND SUNDAY ON THE NAM. NAM/CANADIAN/ECMWF HAVE QPF LINGERING IN THE SOUTHEAST THROUGH SUNDAY. HOWEVER...GFS DRIES OUT LOW AND SOME OF THE MID LEVELS TONIGHT INTO SUNDAY. THIS RESULTS IN A MAINLY DRY SUNDAY IN THE FAR SOUTHEAST. HRRR TRYING TO SHOW A PERIOD OF DRY CONDITIONS LATER THIS EVENING INTO THE OVERNIGHT HOURS BEFORE BRINGING THE SNOW BACK BY 09Z SUNDAY. NAM/MESOSCALE MODELS/SOME SREF ENSEMBLES ARE CRANKING OUT QUITE A BIT OF QPF IN THE FAR SOUTHEAST THROUGH SUNDAY...UP TO AROUND 1/2 INCH IN SOME INSTANCES. FOR NOW...LEANED TOWARD THE WETTER SOLUTIONS...BUT DID NOT GO QUITE AS HIGH AS THEM WITH QPF AND SUBSEQUENT SNOW AMOUNTS. EXPECTING A 3 TO 5 INCH ACCUMULATION NEAR THE BORDER IN KENOSHA COUNTY THROUGH SUNDAY...TO AROUND AN INCH IN A MILWAUKEE TO BELOIT LINE...LOWER TO THE NORTH AND WEST. THESE AMOUNTS COULD BE SOMEWHAT HIGHER IF THE AFOREMENTIONED WETTER LOOKING MODELS VERIFY...SO INCREASING AMOUNTS AND ADJUSTING HEADLINES ARE POSSIBLE IN LATER FORECASTS. STRONG COLD AIR ADVECTION WILL DEVELOP TONIGHT INTO SUNDAY...AS ARCTIC AIRMASS MOVES INTO THE AREA. WIND CHILLS ARE EXPECTED TO DROP QUICKLY AWAY IN SOUTH CENTRAL WISCONSIN LATER TONIGHT...AND ACROSS AREAS AWAY FROM THE LAKE SUNDAY. KEPT WIND CHILL ADVISORIES GOING FROM PREVIOUS FORECAST. TEMPERATURES WILL DROP QUICKLY TONIGHT...AND WILL REMAIN NEARLY STEADY SUNDAY WITH COLD AIR ADVECTION CONTINUING. SUNDAY NIGHT THROUGH TUESDAY...FORECAST CONFIDENCE HIGH. THE FORECAST OF DANGEROUSLY COLD AIR FOR THIS PERIOD REMAINS ON TRACK. STRONG LOW PRESSURE THAT WILL MOVE UP THE OHIO VALLEY TONIGHT AND SUNDAY WILL INTENSIFY FURTHER AND LIKELY RETROGRADE A BIT FARTHER WEST SUNDAY NIGHT INTO MONDAY. THIS MAY ALLOW US TO ADJUST TEMPS UP A DEGREE OR SO...BUT THE WINDS WILL BE STRONGER...SO NO NET GAIN ON THOSE BRUTAL WIND CHILL READINGS. SOME OF THE MODELS SUGGEST THE CHANCE FOR SNOW MAY HANG BACK ACROSS THE FAR EAST INTO SUNDAY NIGHT DUE TO THE RETROGRADE TRACK OF THE LOW. I/LL KEEP A VERY SMALL CHANCE IN THE EAST JUST IN CASE...BUT IT WILL BE MINOR STUFF EITHER WAY. WEDNESDAY THROUGH THURSDAY...FORECAST CONFIDNECE IS MEDIUM. WE START TO SEE A SHIFT TOWARD A WARMER PATTERN BY MID WEEK. TEMPS TUESDAY NIGHT/WEDNESDAY MORNING WILL STILL BE VERY COLD ABOUT -5 TO -10...COLD BUT A DECENT IMPROVEMENT FROM THE PREVIOUS COUPLE OF DAYS. A WARM FRONT APPROACHES FROM THE SOUTH AND THIS COUPLED WITH THE ARRIVAL OF A FAVORABLE ENTRANCE REGION OF AN UPPER JET SHOULD TRIGGER SOME FRONTOGENESIS AND WARM ADVECTION ACROSS THE FRONT. ISENTROPICALLY WE START TO SEE SOME DECENT SATURATION AND ALL THIS COULD RESULT IN SOME LIGHT SNOW WED AND WED NGT WITH ONLY A SMALL CHANCE LINGERING INTO THURSDAY. FRIDAY AND SATURDAY...FORECAST CONFIDENCE IS MEDIUM. TEMPS ARE EXPECTED TO CLIMB TO NEAR OR SLIGHTLY ABOVE NORMAL BY THE END OF NEXT WEEK. HIGHS ARE EXPECTED TO CLIMB INTO THE LOWER TO MID 30S. THIS COMES AS HIGH PRESSURE SLIPS OFF TO THE EAST AND LOW PRESSURE MOVES ACROSS THE NORTHERN TIER OF THE U.S. AVIATION/00Z TAFS/... EXPECT LIGHT TO MODERATE SNOW TO CONTINUE AT THE EASTERN SITES TONIGHT AND SUNDAY...WITH MADISON WEST OF THE SNOW. KENOSHA SHOULD SEE VISIBILITIES DOWN TO AIRFIELD MINIMUMS AT TIMES FOR MOST OF TONIGHT...AND AROUND OR BELOW ALTERNATE MINIMUMS LATER TONIGHT AND SUNDAY. SNOWFALL RATES OF 1/4 INCH PER HOUR ARE EXPECTED TONIGHT...WITH SOME 1/2 INCH PER HOUR RATES POSSIBLE. TOTAL OF 3 TO 5 INCHES ARE POSSIBLE BY LATE SUNDAY HERE. MILWAUKEE AND WAUKESHA MAY SEE A BREAK IN THE SNOW THIS EVENING AND INTO THE OVERNIGHT HOURS...BEFORE IT OCCURS AGAIN LATER TONIGHT INTO SUNDAY. FOR NOW...KEPT SNOW IN TAFS AS AM DOUBTFUL THIS WILL OCCUR. RATES WILL BE 1/4 INCH PER HOUR WHEN THE SNOW FALLS...WITH BRIEF 1/2 INCH PER HOUR RATES POSSIBLE. TOTAL AMOUNTS OF AROUND AN INCH ARE EXPECTED BY LATE SUNDAY. MADISON SHOULD BE JUST WEST OF THE SNOW AREA...AND SHOULD NOT SEE ANY ACCUMULATIONS. SOUTHWEST WINDS WILL SHIFT NORTHWEST EARLY THIS EVENING IN THE EASTERN SITES...AS COLD FRONT SLIDES SOUTHEAST THROUGH THE AREA. WINDS WILL BECOME GUSTY BY SUNDAY AFTERNOON. MAY SEE SOME BLOWING SNOW OCCUR AT THE EASTERN SITES SUNDAY AFTERNOON...BUT VISIBILITIES SHOULD BE ABOVE 3 MILES. MARINE... SMALL CRAFT ADVISORY HAS BEEN ISSUED FOR SUNDAY...WITH A GALE WATCH FOR SUNDAY NIGHT THROUGH MONDAY NIGHT...AS A TIGHT PRESSURE GRADIENT DEVELOPS WITH STRENGTHENING LOW PRESSURE PASSING SOUTHEAST OF THE REGION. GUSTS MAY REACH GALE FORCE AT TIMES SUNDAY NIGHT THROUGH MONDAY NIGHT. HIGH WAVES WILL BE LIMITED TOWARD AND OVER THE OPEN WATERS...IN THE ICE FREE AREAS. GUSTY WINDS MAY LINGER THROUGH TUESDAY NIGHT...UNTIL STRONG LOW PRESSURE MOVES AWAY FROM THE REGION. && .MKX WATCHES/WARNINGS/ADVISORIES... WI...WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR WIZ046-047-051-052-056>060-062>072. WIND CHILL ADVISORY FROM NOON TO 6 PM CST SUNDAY FOR WIZ051-058- 063-064-067>069. WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ046-047- 056-057-062. WINTER WEATHER ADVISORY UNTIL 6 PM CST SUNDAY FOR WIZ070>072. LM...SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR LMZ643>646. GALE WARNING FROM 6 PM SUNDAY TO 4 AM CST TUESDAY FOR LMZ643>646. && $$ UPDATE...HENTZ TONIGHT/SUNDAY AND AVIATION/MARINE...WOOD SUNDAY NIGHT THROUGH SATURDAY...DAVIS
AREA FORECAST DISCUSSION...UPDATED
NWS GREEN BAY WI
851 PM CST SAT JAN 4 2014 NEW INFORMATION ADDED TO UPDATE SECTION .UPDATE... ISSUED AT 841 PM CST SAT JAN 4 2014 COLD AIR STARTING TO BECOME ESTABLISHED ACROSS THE AREA...SLOWLY. EVEN TEMPS BACK IN THE DAKOTAS NOT EXTREMELY COLD YET...SO IT WILL TAKE A WHILE FOR THE BITTERLY COLD AIR TO ARRIVE. WINDS HAVE ACTUALLY DIED OFF IN N-C WI. BUT THEY SHOULD PICK UP AGAIN LATER TNGT AS THE GRADIENT TIGHTENS. START TIME OF THE WIND CHILL ADVISORY IS PROBABLY STILL A LITTLE TOO EARLY...BUT IT SHOULD BE IN THE BALLPARK ACRS THE W. THE E MAY NOT HIT ADVISORY CRITERIA BEFORE TOMORROW NIGHT...BUT THE COMBINATION OF WINDS/TEMPS SHOULD RESULT IN DOUBLE DIGIT BELOW ZERO WIND CHILLS OVER THE E TOMORROW...SO WL LEAVE IT TO THE MIDNIGHT SHIFT TO MAKE ANY FURTHER ADJUSTMENTS TO THE ADVISORY IF NEEDED. 00Z NAM WRAPS PCPN BACK INTO FAR ERN WI TOMORROW EVENING. THAT/S QUITE AMAZING CONSIDERING SFC TEMPS PROGGED TO BE DOUBLE-DIGIT BLO ZERO AT THE TIME. LOOKS LIKE ANY SNOW WOULD OCCUR VERY LATE SUN OR SUN NGT...SO DON/T FEEL THE NEED TO RUSH INTO ANY ADJUSTMENTS THAT FAR OUT INTO THE FORECAST BEFORE THE REST OF THE 00Z PRODUCT SUITE ARRIVES. NO ADDITIONAL HEADLINE CHANGES ANTICIPATED THIS EVENING. UPDATE ISSUED AT 656 PM CST SAT JAN 4 2014 COLD AIR HAS BEEN SLOW TO ADVANCE EASTWARD. ADJUSTED THE HOURLY GRIDS FOR TONIGHT AND TOMORROW AND RE-DID THE WIND CHILLS. LOOKS LIKE WE WON/T GET CLOSE TO MEETING WIND CHILL ADVISORY CRITERIA IN THE WEST UNTIL AT LEAST MIDNIGHT...AND IN THE EAST UNTIL 12Z SUNDAY. AND WE MIGHT NOT REACH ADVISORY CRITERIA AT ALL TOMORROW IN THE E...AS THE EWD PROGRESS OF THE COLD AIR WL BE FURTHER DELAYED BY THE WAVE DEVELOPING ON THE ARCTIC FRONT. BUT WE/VE HAD THE ADVISORY RUNNING FOR SUNDAY FOR QUITE SOME TIME...AND WIND CHILLS SHOULD AT LEAST BE CLOSE TO ADVISORY CRITERIA...SO DON/T WANT TO BAIL ON THE ADVISORY UNLESS IT/S A CERTAINTY IT WON/T VERIFY. THE SECOND FORECAST PROBLEM WILL BE THE TRACK OF THE WV NEWD ALONG THE ARCTIC FRONT. ALMOST ALL THE HI RES MODELS TRACK THE WAVE FAR ENOUGH W TO DRIVE PCPN BACK INTO FAR ERN WI LATE TOMORROW AFTN. WON/T MAKE ANY CHANGES TO THAT ASPECT OF THE FCST YET...WANT TO HAVE SOME TIME TO LOOK OVER AT LEAST SOME OF THE 00Z DATASET BEFORE CONSIDERING ANY CHANGES. UPDATED PRODUCT SUITE WL BE OUT ASAP. && .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 221 PM CST SAT JAN 4 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON. EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON. TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM AS ARCTIC AIR RETURNS. TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23 BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START AT 06Z AS PLANNED. SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 221 PM CST SAT JAN 4 2014 PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY. STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING. WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING HEADLINES STARTING SUNDAY EVENING. FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY NEED TO BE INCREASED A LITTLE. UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 511 PM CST SAT JAN 4 2014 ARCTIC AIR WL BE OVERSPREADING THE AREA DURING THE NEXT 24 HRS. LOW-LEVEL SUBSIDENCE WL GENERATE VFR CONDITIONS. EXPECT INCREASING WINDS TOMORROW AFTN AS WAVE RIDES NEWD ALONG THE ARCTIC FRONT TO OUR E. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ013-020- 021-031-037>039-045-048-049-073-074. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR WIZ005-010>012-018-019-030-035-036. && $$ UPDATE.........SKOWRONSKI SHORT TERM.....MPC LONG TERM......TDH AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
704 PM CST SAT JAN 4 2014 NEW INFORMATION ADDED TO UPDATE SECTION .UPDATE... ISSUED AT 656 PM CST SAT JAN 4 2014 COLD AIR HAS BEEN SLOW TO ADVANCE EASTWARD. ADJUSTED THE HOURLY GRIDS FOR TONIGHT AND TOMORROW AND RE-DID THE WIND CHILLS. LOOKS LIKE WE WON/T GET CLOSE TO MEETING WIND CHILL ADVISORY CRITERIA IN THE WEST UNTIL AT LEAST MIDNIGHT...AND IN THE EAST UNTIL 12Z SUNDAY. AND WE MIGHT NOT REACH ADVISORY CRITERIA AT ALL TOMORROW IN THE E...AS THE EWD PROGRESS OF THE COLD AIR WL BE FURTHER DELAYED BY THE WAVE DEVELOPING ON THE ARCTIC FRONT. BUT WE/VE HAD THE ADVISORY RUNNING FOR SUNDAY FOR QUITE SOME TIME...AND WIND CHILLS SHOULD AT LEAST BE CLOSE TO ADVISORY CRITERIA...SO DON/T WANT TO BAIL ON THE ADVISORY UNLESS IT/S A CERTAINTY IT WON/T VERIFY. THE SECOND FORECAST PROBLEM WILL BE THE TRACK OF THE WV NEWD ALONG THE ARCTIC FRONT. ALMOST ALL THE HI RES MODELS TRACK THE WAVE FAR ENOUGH W TO DRIVE PCPN BACK INTO FAR ERN WI LATE TOMORROW AFTN. WON/T MAKE ANY CHANGES TO THAT ASPECT OF THE FCST YET...WANT TO HAVE SOME TIME TO LOOK OVER AT LEAST SOME OF THE 00Z DATASET BEFORE CONSIDERING ANY CHANGES. UPDATED PRODUCT SUITE WL BE OUT ASAP. && .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 221 PM CST SAT JAN 4 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON. EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON. TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM AS ARCTIC AIR RETURNS. TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23 BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START AT 06Z AS PLANNED. SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 221 PM CST SAT JAN 4 2014 PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY. STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING. WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING HEADLINES STARTING SUNDAY EVENING. FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY NEED TO BE INCREASED A LITTLE. UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 511 PM CST SAT JAN 4 2014 ARCTIC AIR WL BE OVERSPREADING THE AREA DURING THE NEXT 24 HRS. LOW-LEVEL SUBSIDENCE WL GENERATE VFR CONDITIONS. EXPECT INCREASING WINDS TOMORROW AFTN AS WAVE RIDES NEWD ALONG THE ARCTIC FRONT TO OUR E. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ013-020- 021-031-037>039-045-048-049-073-074. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR WIZ005-010>012-018-019-030-035-036. && $$ UPDATE.........SKOWRONSKI SHORT TERM.....MPC LONG TERM......TDH AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
517 PM CST SAT JAN 4 2014 UPDATED AVIATION PORTION FOR 00Z TAF ISSUANCE .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 221 PM CST SAT JAN 4 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON. EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON. TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM AS ARCTIC AIR RETURNS. TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23 BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START AT 06Z AS PLANNED. SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 221 PM CST SAT JAN 4 2014 PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY. STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING. WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING HEADLINES STARTING SUNDAY EVENING. FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY NEED TO BE INCREASED A LITTLE. UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME. && .AVIATION...FOR 00Z TAF ISSUANCE ISSUED AT 511 PM CST SAT JAN 4 2014 ARCTIC AIR WL BE OVERSPREADING THE AREA DURING THE NEXT 24 HRS. LOW-LEVEL SUBSIDENCE WL GENERATE VFR CONDITIONS. EXPECT INCREASING WINDS TOMORROW AFTN AS WAVE RIDES NEWD ALONG THE ARCTIC FRONT TO OUR E. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM CST SUNDAY FOR WIZ013-020-021-031-037>039-045-048-049-073-074. WIND CHILL ADVISORY FROM 9 PM THIS EVENING TO 6 PM CST SUNDAY FOR WIZ005-010>012-018-019-030-035-036. && $$ SHORT TERM.....MPC LONG TERM......TDH AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS WAKEFIELD VA
1232 AM EST SUN JAN 5 2014 .SYNOPSIS... A WARM FRONT FROM THE WEST AND A DEVELOPING COASTAL LOW WILL BRING ANOTHER ROUND OF PRECIPITATION TO THE AREA LATE TONIGHT INTO SUNDAY. A STRONG COLD FRONT WILL CROSS THE REGION LATE SUNDAY NIGHT INTO MONDAY MORNING...FOLLOWED BY A VERY COLD ARCTIC AIRMASS FOR MONDAY AFTERNOON INTO MID-WEEK. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... SEASONABLE CHILL RMNS OVR THE RGN AS SFC HI PRES DRIFTS OFF THE CST. WNDS HAVE BECOME SSE OVR THE ENTIRE FA...GENERALLY AVGG 10 MPH OR LESS. CLOUDS CONTINUE TO SPREAD NORTHEAST ACROSS THE AREA. ALREADY REACHING THE RICHMOND AREA THIS EVENING. LOOKING SOUTHEAST WHERE THE CLOUDS HAVE BEEN ADVECTING UP FROM CAN SEE A SOLID DECK OF CLOUDS. THE RUC AND 18Z NAM SHOW THIS MOISTURE GENERALLY FROM 85H AND UNDER. THIS WILL HOLD TEMPS UP AS CONTINUED SE FLOW BRINGS IN STEADILY MILDER AIR. HAVE RAISED SOME TEMPERATURES A LITTLE AND WHERE THE CLOUDS HAVE ARRIVED HAVE NOT DROPPED TEMPERATURES AT ALL. THIS MEANS THE ONLY AREA NOW EXPECTING TO SETTLE BELOW FREEZING IS THE AREA FROM FVX NORTH THROUGH LOUISA. MDLS ARE DIVERGENT WRT POPS/PCPN...GFS SLOWER AND "DRIER" (W/ JUST LWRG CIGS)...WHILE THE NAM BRINGS IN AT LEAST LGT PCPN TO SCNTRL AND WRN PORTIONS OF THE FA AFT 06-09Z/05. TIME SECTIONS SHOW LITTLE OR NO MOISTURE REACHING NEAR THE MINUS 10 ISOTHERM SO WOULD NOT EXPECT MORE THEN VERY LIGHT PRECIPITATION OR DRIZZLE THROUGH THE NIGHT. ALSO HRRR SEEMS TO HAVE A GOOD HANDLE ON WHERE THE DRIZZLE AND LIGHT PRECIPITATION IS OCCURRING OVER SOUTH CAROLINA AND THAT HOLDS OFF ANY PRECIPITATION UNTIL AROUND SUNRISE IN THE SOUTHWEST. THERE IS LO CONFIDENCE RIGHT NOW FOR ANYTHING MORE THAN A TRACE QPF EVENT... NO HEADLINES ATTM...KEEPING MENTION IN HWO OF POSSIBLE FREEZING PRECIPITATION AROUND SUNRISE. && .SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/... MILDER/WARMER WX XPCD SUN INTO SUN NGT AHD OF APPROACHING LO PRES AND ASSOCIATED CDFNT FM THE W AND WK CSTL LO PRES TRACKING JUST OFF THE NC CST. VERY LIMITED DEPTH TO MOISTURE CONTG TO SPREAD OVR THE RGN DURG SUN...WHICH LIKELY MEANS THAT ANY PCPN WOULD BE LGT...AND MAY BE CONFINED TO AREAS INLAND/AWAY FM THE CST. THERE WILL RMN RESIDUAL CAD W OF I95 ON SUN WHILE THE WARMER AIR ARRIVES NWD ELSW. HI TEMPS FM THE L/M40S NW TO THE U50S/L60S IN SE VA/NE NC. THE WK CSTL LO TRACKS TO THE NE AND AWAY FM THE RGN SUN EVE...WHILE A STRONG CDFNT APPROACHES THE MTNS. THAT FNT MAKES ITS WAY ACRS THE MTNS AND ONTO THE PIEDMONT SUN NGT THROUGH MON MRNG...ACCOMPANIED BY A BAND/AREA OF RA (WHICH MAY MIX W/ SN ON WRN SIDE AS COLDER AIR BEGINS TO ARRIVE). THAT CDFNT CONTS TO PUSH ACRS THE FA DURG TUE...PUSHING OFF THE CST BY MID/LT MON AFTN...USHERING IN ANOTHER SHOT OF VERY COLD/ARCTIC AIR ON INCRSG NW WNDS. SCT-LIKELY SHRAS ACCOMPANY THE FNTL PASSAGE ON MON...WHICH MAY END AS ISOLD/SCT SHSN AS THE COLDER AIR CONTS IT MARCH EWD INTO THE FA (AND TEMPS FALL THROUGHOUT THE MIDDAY/AFTN HRS). LO TEMPS SUN NGT M/U30S FAR W...TO L50S SE. HI TEMPS MON (IN THE MRNG) FM ARND 40F W TO L50S SE. WHAT MAY END OF BEING THE COLDEST SHOT OF AIR INTO THE RGN SINCE FEB 1996 (OR JAN 1994) MON NGT THROUGH TUE. ISOLD/SCT SHSN ARE PSBL INVOF CST/OVR THE OCN (H85 TEMPS DROP TO BLO -18 DEGS C BY 12Z/07). OTRW...CLR TO PCDY...W/ LO TEMPS FM THE SINGLE DIGITS TO TEENS (MON NGT)...THEN HI TEMPS NO HIGHER THAN THE TEENS AND L20S ON TUE. WIND CHILLS MAY DROP TO OR BLO 0 DEGS F FOR A TIME FM LT MON INTO TUE (AS WNDS AVGG 15-25 MPH...W/ GUSTS TO 35-40 MPH PSBL). && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... ARCTIC HIGH PRESSURE BUILDS OVERHEAD TUESDAY NIGHT WITH CURRENT FORECAST LOWS IN THE TEENS. THE HIGH REMAINS OVER THE AREA WEDNESDAY...WHICH WILL LIMIT MIXING AND RESULT IN HIGHS GENERALLY IN THE 30S AREAWIDE. DRY AND MAINLY CLEAR CONDITIONS ARE EXPECTED TUESDAY NIGHT THROUGH WEDNESDAY...ASIDE FROM ANY COLD-AIR CUMULUS STREAMERS OFF THE BAY. THE ARCTIC HIGH SLIDES OFF THE MID ATLANTIC COAST WEDNESDAY NIGHT AND THURSDAY. MEANWHILE...A SHORTWAVE DISTURBANCE APPROACHES FORM THE WEST THURSDAY...AND TRAVERSES ACROSS THE MID ATLANTIC REGION THURSDAY NIGHT INTO FRIDAY MORNING. SURFACE TEMPERATURES SHOULD RISE ABOVE 32 F ACROSS THE ENTIRE LOCAL AREA BY THE TIME ANY LIGHT PRECIP ARRIVES...SO ALL PRECIP IS STILL EXPECTED TO BE RAIN. HIGHS WILL BE NEAR SEASONAL AVERAGES THURSDAY AS CLOUD COVER AND LIMITED MIXING WILL PREVENT HIGHS FROM REACHING THEIR FULL POTENTIAL. ADDITIONAL SHORTWAVE ENERGY/MOISTURE IS EXPECTED TO CROSS THE AREA AT TIMES FROM FRIDAY THROUGH THE WEEKEND AS ANOTHER LONGWAVE TROUGH DIGS OVER THE CENTRAL U.S. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... MOISTURE QUICKLY SPREADING NORTH IN THE FORM OF A BKN-OVC SC DECK (BTWN 2-4K FT ACROSS THE PIEDMONT AND 4-6K FT ALONG THE COAST). LATEST MODELS CONTINUE THIS MVFR-VFR TREND AND KEEP IT DRY THROUGH 12Z...ALTHOUGH SOME DRIZZLE MAY DEVELOP AROUND SUNRISE IVOF RIC. CHALLENGING FORECAST ON WHEN COLUMN BECOMES SATURATED ENOUGH FOR IFR CONDITIONS AS ANY PCPN SHOULD REMAIN RATHER LIGHT THROUGH 18Z AND EVEN LATER ALONG THE COAST. EXPECT STRATUE ALONG WITH PERIODS OF LIGHT RAIN/DRIZZLE TO LOWER TOWARD IFR CONDITIONS BY MID AFTERNOON AT RIC...THEN ALONG COASTAL SECTIONS BEFORE 00Z MON. IFR CIGS AND PCPN CONTINUE SUNDAY NIGHT AHEAD OF ARCTIC COLD FRONT EXPECTED TO CROSS THE AREA MONDAY MORNING. CHANCE OF SHOWERS CONTINUE WITH THE COLD FRONT MONDAY. GIVEN THE STRONG CAA...COULD SEE RAIN SHOWERS MIX WITH OR BRIEFLY CHANGE TO SNOW SHOWERS BEFORE. GUSTY NW WINDS DRY OUT COLUMN MON NGT / TUE. && .MARINE... SEAS ACROSS THE NORTHERN OUTER BANKS CONTINUE TO HOVER BETWEEN 5-6 FT...SO EXTENDED THE SCA THERE THROUGH 4 AM. PVS DSCN: SCA CONTINUES FOR SRN WATERS UNTIL 1 AM EDT FROM THE VA/NC BORDER TO CURRITUCK LIGHT. SEAS OF 5 TO 7 FT WILL PERSIST DURING THIS TIME BEFORE SUBSIDING BELOW 5 FT. A COASTAL LOW BEGINS TO TAKE SHAPE OFF THE FL COAST BY SUN MORNING...THEN DEEPENS AS IT TRACKS ALONG THE CAROLINA COAST TWD THE MID ATLANTIC WATERS DURING THE DAY. THE PRESSURE GRADIENT WILL TIGHTEN AS THE DAY PROGRESSES DUE TO A VERY STRONG ARCTIC COLD FRONT MOVING INTO THE TN/OH VALLEYS. THIS WILL CAUSE SE WINDS TO GRADUALLY INCREASE BY SUN AFTN. THE COASTAL LOW IS USHERING A WAA REGIME OVER THE WATERS DURING THIS TIME AND DO NOT ANTICIPATE MUCH SUCCESS IN MIXING DOWN STRONGER WINDS ALOFT. WILL KEEP WINDS CAPPED JUST BELOW SCA CRITERIA (15 KT BAY/RIVERS/SOUND...25 KT OCEAN) FROM SUN AFTN INTO SUN NIGHT. THE AFOREMENTIONED ARCTIC COLD FRONT IS EXPECTED TO RAPIDLY STRENGTHEN SUN NIGHT INTO MON MORNING AS IT MOVES FROM THE OH/TN VALLEYS INTO THE ERN GREAT LAKES REGION. THE VERY STRONG ARCTIC COLD FRONT ASSOCIATED WITH THIS SYSTEM IS EXPECTED TO CROSS THE WATERS MON MORNING THROUGH EARLY AFTN. S WINDS OF 20-25 KT MON MORNING WILL QUICKLY VEER TO THE NW BEHIND THE VIGOROUS FRONTAL PASSAGE AND INCREASE TO 25-30 KT. GUSTS UP TO 40 KT SHOULD BE ANTICIPATED OVER THE COASTAL WATERS IN ADDITION TO LOW-END GALE FORCE GUSTS POSSIBLE ON CHES BAY. WAVES/SEAS ARE ALSO EXPECTED TO RAPIDLY BUILD IN THE VICINITY OF THE COLD FRONT (CHES BAY WAVES 4-5 FT/COASTAL WATERS SEAS 5-8 FT). ALTHOUGH FORECAST MODELS HAVE BEEN FAIRLY CONSISTENT WITH THE TIMING OF THE FRONTAL PASSAGE ON MON...AM CONCERNED THAT A DEEP LONGWAVE TROUGH OVER THE CTRL U.S. WILL DIG A BIT DEEPER THAN EXPECTED. IF THIS OCCURS...THEN THE FRONTAL PASSAGE COULD BE SLOWED BY A FEW HOURS AND THUS DELAY THE ONSET OF STRONGER WINDS OVER THE WATERS MON MORNING. ON THE OTHER HAND...THE ARCTIC AIRMASS BEHIND THE COLD FRONT MAY PUSH THE FRONT ACROSS THE WATERS A FEW HOURS FASTER THAN ANTICIPATED. SINCE CURRENT FORECAST HAS WINDS INCREASING LATE IN THE THIRD PERIOD (OR JUST INSIDE 36 HOURS)...HAVE OPTED NOT TO ISSUE SCA OR GALE HEADLINES WITH THIS FORECAST ISSUANCE. VERY STRONG CAA MOVES OVER THE WATERS MON EVENING/OVERNIGHT AS A VERY COLD ARCTIC AIRMASS MOVES INTO THE MID ATLANTIC REGION BEHIND THE DEPARTING FRONT. THE SFC PRESSURE GRADIENT IS EXTREMELY TIGHT DUE TO THE VAST TEMPERATURE DIFFERENCES AHEAD OF AND BEHIND THE ARCTIC FRONT. TAKING THIS INTO CONSIDERATION...THERE MAY BE A PERIOD OF STRONGER WINDS (STILL GALE FORCE) WITH THE INITIAL COLD AIR PUSH WHICH FORECAST MODELS ARE NOT PICKING UP ON ATTM. HAVE MAINTAINED THE PREVIOUS FORECAST WIND STRENGTH THROUGH MON NIGHT... WHICH WAS ALREADY HIGHER THAN MODEL GUIDANCE. HOWEVER THIS MAY NEED TO BE INCREASED BY ANOTHER 5-10 KT ALL WATERS. BECAUSE WINDS BACK FROM NW TO W MON NIGHT...THE WIND SHIFT MAY BE ENOUGH TO HAMPER THE POTENTIAL FOR PROLONGED GALES VERSUS IF THE WINDS STAYED NW-N DURING THE COLD AIR SURGE. W WINDS REMAIN STRONG THROUGH TUE. THEN HIGH PRESSURE BUILDS INTO THE REGION FROM THE WEST AND THE TEMP/PRESSURE GRADIENT BEGINS TO RELAX...THUS ALLOWING WINDS TO SLOWLY DIMINISH DURING THE LATE AFTN/EVENING. SEAS SHOULD FOLLOW THE SAME TREND DURING THIS TIME BUT SHOULD NOT FALL BELOW 5 FT UNTIL CLOSER TO WED MORNING. HIGH PRESSURE CROSSES THE WATERS WED/THU WITH MORE BENIGN CONDITIONS EXPECTED. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL 4 AM EST EARLY THIS MORNING FOR ANZ658. && $$ SYNOPSIS...ALB/BMD/JDM NEAR TERM...ALB/JAB SHORT TERM...ALB LONG TERM...BMD AVIATION...MPR MARINE...BMD/MPR
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
451 AM EST SUN JAN 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 448 AM EST SUN JAN 5 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP POLAR VORTEX CENTERED OVER SCENTRAL CANADA...WITH CORE OF ARCTIC AIRMASS ACCOMPANIED BY 00Z H5/H85/H925 TEMPS AS LO AS -43C/-31C/-34C AT THE PAS MANITOBA. UPR MI IS ON THE PERIPHERY OF THE VERY COLD AIRMASS ATTM...WITH 00Z H85 TEMPS RANGING FM -6C AT GRB TO -24C AT INL. LVL WNW FLOW TO THE E OF SFC HI PRES IN THE NRN PLAINS IS ADVECTING THE COLDER AIR INTO UPR MI...BUT RELATIVELY LIGHT WINDS HAVE SLOWED THE ADVECTION. THIS COLD FLOW OVER THE RELATIVELY WARM WATERS OF LK SUP IS CAUSING THE TYPICAL LK CLDS/LES IN THE FAVORED SN BELTS...BUT LO INVRN BASE ARND H9 AS SHOWN ON THE 00Z INL/GRB RAOBS AS WELL AS DRY NATURE OF THE LLVLS IS LIMITING THE INTENSITY OF THE SHSN. OTRW... QUITE A BIT OF HI CLD IS STREAMING OVER MAINLY THE SE HALF OF THE CWA WELL TO THE N OF SFC LO PRES DVLPG IN THE LOWER MS RIVER VALLEY. MAIN FCST CONCERNS THRU THE SHORT TERM FOCUS ON TEMPS/WIND CHILLS/ GOING HEADLINES AS WELL AS LES/BLSN. TODAY...THE CORE OF THE ARCTIC AIR OVER SCENTRAL CANADA EARLY THIS MRNG IS FCST TO DROP OVER MN BY 00Z MON. AS THE TROF OVER CENTRAL NAMERICA DEEPENS...THE SFC LO NOW OVER THE LOWER MS RIVER VALLEY IS PROGGED TO DEEPEN AND MOVE INTO THE OH RIVER VALLEY. ALTHOUGH THE LARGER SCALE FORCING/ASCENT/DEEP MOISTENING ASSOCIATED WITH THIS LO WL REMAIN TO THE E-SE OF UPR MI...THE PRES GRADIENT/LLVL NW FLOW OVER THE AREA IS FCST TO SHARPEN AND INCRS THE ADVECTION OF THE COLDER AIR INTO THE CWA. MODEL CONSENSUS SHOWS H85 TEMPS FALLING FM -23C OVER THE NW/-14C OVER THE SE AT 12Z TO -29C OVER THE NW/-19C OVER THE SE BY 00Z MON. AS A RESULT...THE DIURNAL TEMP RECOVERY... ESPECIALLY OVER THE WRN ZNS...WL BE NEGLIGIBLE. ALTHOUGH THE SURGE OF LLVL COLD AIR WL SUPPORT ONGOING LES...THE LO INVRN BASES ARND 3-4K FT AND ACYC NATURE OF THE H925 FLOW/GENERAL SUBSIDENCE WL LIMIT SN AMOUNTS...ESPECIALLY OVER THE W WHERE THE DGZ WL DESCEND INTO THE GROUND AND LIMIT SN GROWTH. THERE MAY BE AN UPTICK IN THE LES IN THE NW WIND SN BELTS E OF MQT LATER IN THE DAY HOWEVER AS LLVL CNVGC ON LK INDUCED TROF SHARPENS UNDER DEEPENING UPR TROF. AS FOR GOING WIND CHILL HEADLINES...OPTED TO DROP BARAGA...MARQUETTE AND DICKINSON COUNTIES FM THE HEADLINE GIVEN CURRENT CONDITIONS AND EXPECTATION THAT THESE AREAS WL NOT MEET CRITERIA MOST OF THE THE DAY. TONIGHT...THE LO TO THE SE IS PROGGED TO DEEPEN SGNFTLY AND LIFT NEWD INTO SE CANADA AS THE CENTRAL CONUS TROF SHARPENS WITH MORE PHASING OF THE ARCTIC AND POLAR BRANCHES. THE CORE OF THE COLDEST AIR...WITH H85 TEMPS DOWN TO -33C TO -35C...IS PROGGED TO SHIFT OVER WI. AS THE LO DEEPENS...THE PRES GRADIENT WL SHARPEN FURTHER OVER THE UPR LKS...ALLOWING H925 NW WINDS TO INCRS TO 25 TO 30 KTS. THE STRENGTHENING WINDS AND FALLING TEMPS SUPPORT GOING WIND CHILL WRNGS AWAY FM THE LK MODERATION THAT WL IMPACT MAINLY THE ERN CWA EVEN THOUGH A MORE N WIND COMPONENT OFF LK SUP MIGHT NOT ALLOW TEMPS TO FALL AS LO AS PREVIOUS FCST. BUT OVER THE ERN CWA...THE ARRIVAL OF DEEPER MSTR ASSOCIATED WITH ARRIVAL OF DEEP LYR QVECTOR CNVGC UNDER THE FALLING HGTS ASSOCIATED WITH THE DEEPENING UPR TROF AS WELL AS INCRSG LLVL CNVGC ACCOMPANYING THE SHARPENING OF THE LK INDUCED SFC TROF WL GIVE A BOOST TO THE LES. WITH MORE FVRBL SN GROWTH...H85 TEMPS ARE PROGGED TO FALL TO ARND -24C HERE BY 12Z MON...AS WELL AS INCRSG BLSN...OPTED TO REPLACE THE WIND CHILL ADVY FOR ALGER/LUCE/ SCHOOLCRAFT COUNTIES WITH A LK EFFECT SN ADVY TO ACCOUNT FOR SN FALL AT LEAST APRCHG ADVY AMOUNTS...BLSN AND WIND CHILLS AT LEAST APRCHG ADVY CRITERIA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 448 AM EST SUN JAN 5 2014 THE MAIN CONCERN FOR THE LONG TERM FORECAST WILL BE EXTREMELY COLD TEMPERATURES/WIND CHILLS AND REDUCED VISIBILITIES FROM LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW. LOW PRESSURE TRAVELING FROM THE OHIO VALLEY TODAY WILL REACH QUEBEC BY MONDAY MORNING. MEANWHILE...A COLD ARCTIC AIRMASS/HIGH PRESSURE WILL SINK FROM THE CANADIAN PRAIRIE INTO THE MIDWEST AND CENTRAL PLAINS. AS THIS HIGH SINKS TOWARDS THE GULF COAST MONDAY NIGHT...THE LOW OVER QUEBEC WILL DRIFT WESTWARD INTO JAMES BAY. THIS PATTERN WILL KEEP UPPER MICHIGAN IN A MODERATE WEST-NORTHWESTERLY FLOW THROUGH WEDNESDAY...AS A TIGHTER PRESSURE GRADIENT SITS OVER THE AREA. ADDITIONALLY...A 500MB LOW WILL CENTER ITSELF OVER UPPER MI MONDAY MORNING...THEN DRIFT SLOWLY NORTHEASTWARD INTO ONTARIO AND QUEBEC. WITH THE LOW CENTERED OVER UPPER MI 850-500MB QVECTOR CONVERGENCE IS MAXIMIZED OVER THE EASTERN U.P. AND LOWER MI. WITH NORTHWESTERLY WINDS MOVING THE COLD ARCTIC AIR OVER LAKE SUPERIOR...KEPT POPS IN NORTHWEST WIND FAVORED SNOWBELTS. ALSO INCREASED POPS IN THE EASTERN CWA AS THE UPPER LEVEL SUPPORT CROSSES THROUGH THE AREA WITH THE TROUGH. WINDS GENERALLY REMAIN NORTHWESTERLY THROUGH MONDAY AFTERNOON...THEN BEGIN TO BACK TOWARDS THE WEST-NORTHWEST WIND DIRECTION. ADJUSTED POPS ACCORDINGLY...WITH THE MAIN CORE OF PRECIPITATION IN THE EASTERN U.P. SHIFTING TO AREAS FAVORED BY WNW WINDS...MAINLY EAST OF MUNISING. ON TUESDAY SEVERAL SMALL SHORTWAVES SNEAK ALONG THE BASE OF THE TROUGH ALOFT AS IT MOVES EASTWARD...AND WNW WINDS BECOME MORE WESTERLY TOWARDS THE EVENING. MOST OF THE SNOW BY LATE TUESDAY AFTERNOON WILL BE OVER THE KEWEENAW AND EAST OF GRAND MARAIS. LIMITING FACTORS TO SIGNIFICANT ACCUMULATIONS WILL BE THE EXTREMELY COLD/DRY AIRMASS. THIS SENDS THE DGZ CRASHING INTO THE GROUND FOR MOST LOCATIONS...ESPECIALLY MONDAY NIGHT INTO TUESDAY AFTERNOON. AS A RESULT SNOW RATIOS WILL BE ON THE ORDER OF 15-18:1 AND FLAKES VERY FINE. AS FAR AS MOISTURE GOES...PWATS DURING THIS TIME FRAME DROP TO NEAR 15 PERCENT OF NORMAL FOR UPPER MI. OVERALL...FROM MONDAY MORNING THROUGH TUESDAY MORNING...HAVE 2-4 INCHES FOR AREAS FAVORED BY WEST-NORTHWEST WINDS. TUESDAY MORNING INTO WED MORNING ONLY HAVE 1-3 INCHES FOR THE SAME AREAS...MAINLY THE KEWEENAW AND EAST OF MUNISING NEAR LAKE SUPERIOR. THE COLD ARCTIC AIRMASS WILL BRING LOW TEMPERATURES CRASHING DOWN TO -27F OUT WEST...AND THE TEENS BELOW ZERO EAST FOR MONDAY NIGHT. AREAS NEAR THE LAKE WILL SEE TEMPERATURES DROP DOWN TO THE SINGLE DIGITS BELOW ZERO FARTHER EAST AND OVER THE KEWEENAW. WITH THE STRONGER WINDS OVER THE AREA HOWEVER...WIND CHILLS WILL DROP AS LOW AS -50F ACROSS THE WEST...AND MAINLY THE -30S AND -40S ELSEWHERE...EVEN NEAR THE LAKE. THOUGH SNOW ACCUMULATIONS WILL NOT BE HAZARDOUS BY THEMSELVES...THE COMBINATION OF SNOW...BLOWING SNOW...AND DANGEROUSLY LOW TEMPERATURES/WIND CHILLS WARRANT A LAKE EFFECT SNOW ADVISORY FOR AREAS IN THE EAST...MAINLY FOR ALGER/LUCE/SCHOOLCRAFT COUNTIES. WIND CHILLS WILL REACH ADVISORY CRITERIA...AND THE COMBINATION OF SNOW AND BLOWING SNOW/DUE TO WINDS AROUND 30 MPH/ WILL REDUCE VISIBILITIES DRAMATICALLY...ESPECIALLY WITH THE FINER FLAKES. ELSEWHERE...HAVE ONLY THE WIND CHILL WARNING IN EFFECT FOR THE MONDAY-TUESDAY TIME FRAME. THE KEWEENAW WILL ALSO SEE STRONG WINDS...GUSTING TO 25 TO 30 MPH...AND PERSISTENT LAKE EFFECT SNOW WITH AREAS OF BLOWING SNOW DURING THE MONDAY-TUESDAY TIME FRAME. HAVE INCLUDED THIS WORDING IN THE WIND CHILL WARNING FOR THE KEWEENAW/HOUGHTON COUNTIES FOR SIMPLICITY WITH HEADLINES. WINDS WILL GRADUALLY DIE DOWN FROM WEDNESDAY INTO THURSDAY AS THE HIGH CENTERS ITSELF OVER THE GREAT LAKES. LIGHT AND VARIABLE WINDS WILL GRADUALLY TRANSITION TO MORE MODERATE SOUTH TO SOUTHWESTERLY WINDS AS THE HIGH SHIFTS EASTWARD TOWARDS THE NEW ENGLAND STATES...AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA. SOME OF THE MODELS ATTEMPT TO BRING A WEAK SHORTWAVE TROUGH INTO THE MIDWEST LATE FRIDAY AFTERNOON AND SATURDAY...BUT OTHERS KEEP MORE ZONAL FLOW OVER THE AREA. WILL KEEP THE CONSENSUS POPS DURING THIS TIME FRAME HOWEVER...WITH THE WNW-LAKE EFFECT MOVING OUT INTO THE LAKE AS WINDS BACK TO THE SOUTH-SOUTHWEST. && .AVIATION...(FOR THE 06Z TAFS THROUGH 06Z SUNDAY NIGHT) ISSUED AT 1226 AM EST SUN JAN 5 2014 COLD AIR CONTINUES TO FILTER ACROSS THE UPPER LAKES...WITH LAKE EFFECT SNOW SHOWERS CONTINUING ACROSS THE KEWEENAW PENINSULA INCLUDING KCMX. SEE NO REASON WHY THE SNOW SHOWERS WILL NOT CONTINUE THROUGH THE PERIOD AT KCMX AS THE ARCTIC AIRMASS MOVES OVERHEAD LATE SUNDAY. EXPECT MVFR CONDITIONS AT CMX TO CONTINUE OVERNIGHT INTO EARLY SUNDAY AFTERNOON BEFORE STRONGER WINDS AND FINE SNOWFLAKES HELP TO REDUCE THE VSBY TO IFR DESPITE THE SNOW NOT EXPECTED TO BE TERRIBLY HEAVY. AS FOR IWD...A LIGHT LAND BREEZE HAS DEVELOPED WHICH SHOULD HELP TO KEEP SNOW NORTH OF THE SITE TONIGHT. AS THE WINDS SHIFT BACK TO THE W-NW ON SUNDAY...EXPECT A RETURN OF SNOW SHOWERS WITH MVFR VSBYS. THE W-NW FLOW AT KSAW SHOULD KEEP VFR VSBYS THROUGH THE PERIOD. IN FACT...THE MVFR CEILING MAY DISAPPEAR OVERNIGHT AS THE ARCTIC AIRMASS BUILDS ACROSS THE AREA...HOWEVER EXPECT IT TO RETURN ON SUNDAY AS THE FLOW BECOMES NORTHWESTERLY AGAIN WITH A SLIGHT INCREASE OF LOWER MOISTURE. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 448 AM EST SUN JAN 5 2014 A GALE WATCH IS IN EFFECT FOR CENTRAL AND EASTERN LAKE SUPERIOR MONDAY MORNING THROUGH TUESDAY NIGHT...AND A HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT... EXPECT NW WINDS 20-25 KTS THIS MORNING TO INCREASE TO 25-30 KTS LATER TODAY AND TONIGHT AS THE PRES GRADIENT OVER THE UPPER GREAT LAKES SHARPENS TO THE NW OF A DEEPENING LO PRES MOVING NE THRU THE SE GREAT LAKES INTO SE CANADA. THERE MAY BE A FEW GALE FORCE GUSTS OVER PORTIONS OF THE E LAKE LATE TONIGHT AS WELL. WITH ARCTIC AIR PERSISTING OVER THE AREA...EXPECT PERIODS OF HEAVY FREEZING SPRAY... ESPECIALLY OVER THE E HALF WHERE WINDS WILL BE STRONGEST. LAKE SUPERIOR WILL BE CAUGHT THIS TIGHT PRESSURE GRADIENT BETWEEN STRONG ARCTIC HIGH PRESSURE OVER THE PLAINS AND STRONG LOW PRESSURE OVER QUEBEC MONDAY INTO TUESDAY. AS A RESULT...WEST NORTHWEST GALES TO 35 KNOTS WILL OCCUR OVER MAINLY CENTRAL AND EASTERN LAKE SUPERIOR ON MONDAY AFTERNOON...AND WEST NORTHWEST GALES TO 40 KNOTS WILL OCCUR ON TUESDAY AFTERNOON. WINDS ON WESTERN LAKE SUPERIOR WILL LARGELY REMAIN WEST-NORTHWEST AT 20 TO 30 KNOTS DURING THIS TIME. ADDITIONALLY...COLD ARCTIC AIR IN PLACE OVER LAKE SUPERIOR COMBINED WITH THE STRONG WINDS WILL LEAD TO HEAVY FREEZING SPRAY FOR ALL OF THE LAKE THROUGH WEDNESDAY MORNING. ON WEDNESDAY AND THURSDAY HIGH PRESSURE WILL MAKE ITS WAY NORTHWARD...CENTERING ITSELF OVER THE GREAT LAKES. AS A RESULT...GUSTY WEST NORTHWEST WINDS WILL DIE DOWN...EVENTUALLY BACKING SOUTHWEST AT LESS THAN 10 KNOTS BY THURSDAY. AS THE HIGH SHIFTS TO THE NEW ENGLAND STATES AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA FRIDAY AFTERNOON AND SATURDAY...SOUTHWESTERLY WINDS WILL PICK UP TO 15 TO 25 KNOTS OVER ALL OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 11 AM EST /10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084. WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR MIZ002-009-010-084. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST MONDAY FOR MIZ006-007-014-085. WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR MIZ006-007-014-085. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-243>245-248>251-263>267. GALE WATCH FROM MONDAY MORNING THROUGH LATE TUESDAY NIGHT FOR LSZ243>245-264>266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MCD AVIATION...MRD MARINE...KC/MCD
AREA FORECAST DISCUSSION...UPDATED AVIATION
NWS ST LOUIS MO
1153 PM CST Sat Jan 4 2014 .UPDATE: Issued at 810 PM CST Sat Jan 4 2014 Going to be making a few tweaks to the going forecast based on the latest model data that is coming in. 1. Precipitation will stay in liquid form across far southern CWA for much of the overnight period, and perhaps into Sunday morning. Still forecasting just over six inches for storm total - so no headline changes needed. 2. Latest NAM, HRRR and RAP model runs show intense upward vertical motion and convective potential due to steep lapse rates and hints of true CAPE, or upright convective potentional, tomorrow morning across the warned area and therefore will be adding mention of thunder to forecast. Certainly potential for localized snowfall totals over 12 inches. Updated forecast and graphics will be out by 9 p.m. CVKING && .SHORT TERM: (Through Tuesday Afternoon) Issued at 342 PM CST Sat Jan 4 2014 (Tonight - Sunday) Main forecast issue here is major winter storm set to impact the entire area. Forecast by and large is on track from previous shifts with only minor adjustments made. A major winter storm is set to develop later tonight and continue thru much of the day on Sunday. The components for this storm include a strong shortwave over the east-central Rockies which is expected to drop a bit further south before moving east into the Mid-MS valley, being steered on this track by a powerful Polar vortex located over northern MN and western Ontario. By nightfall Sunday afternoon-evening, pcpn is expected to have ended over our region, other than some stray flurries. In the meantime, a cold front, now entering northeast MO, will continue to push SE thru our region, getting thru the final SE MO and S IL counties by daybreak Sunday. Temps will fall several degrees behind this front and will have no problem dropping into the 20s and below, given this is the leading edge of very bitter cold air. Ahead of the front, however, temps will struggle to drop below freezing with clouds and south winds. Pcpn associated with the front has already taken shape in NW MO and S IA and N IL and this band of snow will gradually drop SE into the UIN area this evening and into mid-MO by late evening before some measure of re-organization takes place as the main system strengthens to the W. Pcpn-types may be rain or sleet early but should quickly become all snow with approach of or passage of cold front and should only be a minor concern. The stronger system snow will merge with and overtake the frontal snow late tonight as incredible lift thanks to frontogenesis and jet dynamics enters central and SE MO and then propagates northeastward into STL Metro Sunday morning and eventually into SW IL for a good portion on Sunday. Goree-Younkin-Brown technique continues to target a track from the central Ozarks to just S and E of downtown STL City and curving northeastward into IL for heaviest snowfall potential, with a foot or more of new snow not out of the question. Snowfall amounts associated with maps represent median, most likely values, but higher amounts near the track described above quite possible with higher liquid-to-snow ratios (LSRs) as very cold air builds in at the lo levels. During its peak from very late tonight thru Sunday morning and into early afternoon, snowfall rates at times may top 2" per hour. The visibility reductions with snow combined with wind gusts of 30-35 mph will result in near blizzard conditions for a time on Sunday. When it is done by nightfall early Sunday evening, snowfall amounts from 4-6" can be expected along a UIN-COU axis with 8-12" for STL metro and areas just S and E with locally higher amounts. However, that is only the beginning. Blowing snow will begin to be a real issue by late Sunday morning on once enough snow has fallen and strong winds kick in from the strong CAA. This will lead to impassable roads in places and very lo visibilities. Winter storm headline types will continue with only slight adjustments to timing at the end. (Sunday Night - Tuesday) Main forecast issue for this period will be extreme cold, with winds dropping wind chill values to dangerous levels. Lingering issues from the winter storm will also be a concern. Blowing snow issues will continue thru at least Sunday night and perhaps into Monday as the coldest air of my career builds in, maintaining the strong winds, acting upon what should be a deep snowpack across much of our region. Of greater concern is widespread sub-zero temps...dipping to 5 to 15 below Sunday night...only rising to zero to 5 below on Monday... dropping again to zero to 10 below Monday night...finally bobbing above zero on Tuesday. We have not seen a prolonged period of sub-zero for most locations for two or three decades and this cannot be emphasized enough...this cold will be extremely dangerous when combined with the wind...giving us once-in-a-generation magnitude of cold...taking mere minutes to frostbite on exposed skin. Despite being a couple days out, went ahead and will issue a wind chill warning to elevate the word on the danger that the cold and wind will bring to our area. TES .LONG TERM: (Wednesday through Next Saturday) Issued at 342 PM CST Sat Jan 4 2014 The moderation in temperatures that begins on Tuesday will continue throughout the week as longwave pattern transitions to a zonal flow pattern over the CONUS, shunting the coldest air to our north. By Friday and Saturday it would appear that high temps will finally rebound to near average temperatures, ranging from the middle 30s in the north to the middle 40s in the south. Medium range solutions are still forecasting several shortwave trofs to push into the Central U.S. during the latter half of the week, with ascent associated with these features combining with isentropic lift and moisture advection in the return flow to produce several chances for precipitation. As mentioned in previous AFD, p-type gets a bit tricky with time: initially all snow, but with a slow warming throughout the lower troposphere ptype there may be a transition to sleet over southern areas Wednesday night and Thursday. By Friday, continuing warming appears to support all rain, with a threat of freezing rain during the morning as surface temps are below 32 at that time. TRUETT && .AVIATION: (For the 06z TAFs through 06z Sunday Night) Issued at 1145 PM CST Sat Jan 4 2014 Not much has changed in the overall forecast. Confidence has increased that very heavy snowfall is anticipated for SUS/STL/CPS shortly after what should be sunrise...12z. Have lowered visbys, but to keep TAF shorter, not as low as what that time period may see at times. Other question is timing of onset for SUS/STL/CPS as precip will be coming from N as well as the S. Light RA or DZ shud continue off and on until SN finally begins. For UIN/COU, event is underway and timing still appears to be on track. && .CLIMATE: Issued at 1130 PM CST Thu Jan 2 2014 Last occurrence of a min temp of zero degrees or lower at KSTL: 0 on January 21, 2011 -5 on January 5, 1999 RECORD LOW TEMPERATURES January 6 January 7 St. Louis -11/1884 -14/1912 Columbia -12/1912 -20/1912 Quincy -9/1970 -19/1912 RECORD LOW MAXIMUM TEMPERATURES January 6 January 7 St. Louis 0/1912 0/1912 Columbia -3/1912 2/1912 Quincy -3/1912 -2/1912 Phillipson && .LSX WATCHES/WARNINGS/ADVISORIES: MO...WINTER STORM WARNING until 6 PM CST Sunday FOR Crawford MO-Iron MO-Jefferson MO-Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO-Washington MO. WIND CHILL WARNING from Midnight Sunday Night to Noon CST Tuesday FOR Crawford MO-Iron MO-Madison MO-Reynolds MO-St. Francois MO-Ste. Genevieve MO-Washington MO. WINTER STORM WARNING until 3 PM CST Sunday FOR Franklin MO- Gasconade MO-Lincoln MO-Montgomery MO-Osage MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WIND CHILL WARNING from 6 PM Sunday to Noon CST Tuesday FOR Audrain MO-Boone MO-Callaway MO-Cole MO-Franklin MO- Gasconade MO-Jefferson MO-Knox MO-Lewis MO-Lincoln MO- Marion MO-Moniteau MO-Monroe MO-Montgomery MO-Osage MO-Pike MO-Ralls MO-Shelby MO-St. Charles MO-St. Louis City MO-St. Louis MO-Warren MO. WINTER WEATHER ADVISORY until 3 PM CST Sunday FOR Audrain MO- Boone MO-Callaway MO-Cole MO-Knox MO-Lewis MO-Marion MO- Moniteau MO-Monroe MO-Pike MO-Ralls MO-Shelby MO. IL...WINTER STORM WARNING until 6 PM CST Sunday FOR Bond IL-Clinton IL-Fayette IL-Marion IL-Monroe IL-Montgomery IL-Randolph IL- St. Clair IL-Washington IL. WIND CHILL WARNING from Midnight Sunday Night to Noon CST Tuesday FOR Randolph IL. WINTER STORM WARNING until 3 PM CST Sunday FOR Calhoun IL-Greene IL-Jersey IL-Macoupin IL-Madison IL. WIND CHILL WARNING from 6 PM Sunday to Noon CST Tuesday FOR Adams IL-Bond IL-Brown IL-Calhoun IL-Clinton IL-Fayette IL- Greene IL-Jersey IL-Macoupin IL-Madison IL-Marion IL-Monroe IL-Montgomery IL-Pike IL-St. Clair IL-Washington IL. WINTER WEATHER ADVISORY until 3 PM CST Sunday FOR Adams IL-Brown IL-Pike IL. && $$ WFO LSX
AREA FORECAST DISCUSSION
NWS GREEN BAY WI
1012 PM CST SAT JAN 4 2014 UPDATED AVIATION PORTION FOR 06Z TAF ISSUANCE .UPDATE... ISSUED AT 841 PM CST SAT JAN 4 2014 COLD AIR STARTING TO BECOME ESTABLISHED ACROSS THE AREA...SLOWLY. EVEN TEMPS BACK IN THE DAKOTAS NOT EXTREMELY COLD YET...SO IT WILL TAKE A WHILE FOR THE BITTERLY COLD AIR TO ARRIVE. WINDS HAVE ACTUALLY DIED OFF IN N-C WI. BUT THEY SHOULD PICK UP AGAIN LATER TNGT AS THE GRADIENT TIGHTENS. START TIME OF THE WIND CHILL ADVISORY IS PROBABLY STILL A LITTLE TOO EARLY...BUT IT SHOULD BE IN THE BALLPARK ACRS THE W. THE E MAY NOT HIT ADVISORY CRITERIA BEFORE TOMORROW NIGHT...BUT THE COMBINATION OF WINDS/TEMPS SHOULD RESULT IN DOUBLE DIGIT BELOW ZERO WIND CHILLS OVER THE E TOMORROW...SO WL LEAVE IT TO THE MIDNIGHT SHIFT TO MAKE ANY FURTHER ADJUSTMENTS TO THE ADVISORY IF NEEDED. 00Z NAM WRAPS PCPN BACK INTO FAR ERN WI TOMORROW EVENING. THAT/S QUITE AMAZING CONSIDERING SFC TEMPS PROGGED TO BE DOUBLE-DIGIT BLO ZERO AT THE TIME. LOOKS LIKE ANY SNOW WOULD OCCUR VERY LATE SUN OR SUN NGT...SO DON/T FEEL THE NEED TO RUSH INTO ANY ADJUSTMENTS THAT FAR OUT INTO THE FORECAST BEFORE THE REST OF THE 00Z PRODUCT SUITE ARRIVES. NO ADDITIONAL HEADLINE CHANGES ANTICIPATED THIS EVENING. UPDATE ISSUED AT 656 PM CST SAT JAN 4 2014 COLD AIR HAS BEEN SLOW TO ADVANCE EASTWARD. ADJUSTED THE HOURLY GRIDS FOR TONIGHT AND TOMORROW AND RE-DID THE WIND CHILLS. LOOKS LIKE WE WON/T GET CLOSE TO MEETING WIND CHILL ADVISORY CRITERIA IN THE WEST UNTIL AT LEAST MIDNIGHT...AND IN THE EAST UNTIL 12Z SUNDAY. AND WE MIGHT NOT REACH ADVISORY CRITERIA AT ALL TOMORROW IN THE E...AS THE EWD PROGRESS OF THE COLD AIR WL BE FURTHER DELAYED BY THE WAVE DEVELOPING ON THE ARCTIC FRONT. BUT WE/VE HAD THE ADVISORY RUNNING FOR SUNDAY FOR QUITE SOME TIME...AND WIND CHILLS SHOULD AT LEAST BE CLOSE TO ADVISORY CRITERIA...SO DON/T WANT TO BAIL ON THE ADVISORY UNLESS IT/S A CERTAINTY IT WON/T VERIFY. THE SECOND FORECAST PROBLEM WILL BE THE TRACK OF THE WV NEWD ALONG THE ARCTIC FRONT. ALMOST ALL THE HI RES MODELS TRACK THE WAVE FAR ENOUGH W TO DRIVE PCPN BACK INTO FAR ERN WI LATE TOMORROW AFTN. WON/T MAKE ANY CHANGES TO THAT ASPECT OF THE FCST YET...WANT TO HAVE SOME TIME TO LOOK OVER AT LEAST SOME OF THE 00Z DATASET BEFORE CONSIDERING ANY CHANGES. UPDATED PRODUCT SUITE WL BE OUT ASAP. && .SHORT TERM...TONIGHT AND SUNDAY ISSUED AT 221 PM CST SAT JAN 4 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW AN ARCTIC COLD FRONT MOVING EAST OVER NORTHEAST WISCONSIN EARLY THIS AFTERNOON. EARLIER FREEZING DRIZZLE OVER CENTRAL AND NORTH-CENTRAL WISCONSIN HAS MOSTLY DISSIPATED...AND ONLY A FEW FLURRIES ARE LEFT OVER THE NORTH. MEANWHILE...CLEARING SKIES ARE WORKING THEIR WAY WEST FROM MINNESOTA INTO CENTRAL WISCONSIN...BUT WILL TAKE A FEW MORE HOURS FOR THE NORTH TO CLEAR. FARTHER EAST...SOUTHWEST WINDS IN THE UPPER LEVELS ARE KEEPING A MID-LEVEL CLOUD DECK OVER THE LOW STRATUS ALONG THE FRONT. THIS MID-LEVEL CLOUD DECK WILL HANG AROUND INTO THE EVENING PERIOD. BEHIND THE FRONT...TEMPERATURES ARE GRADUALLY FALLING BUT THE ARRIVAL OF THE COLDER AIR OVER THE DAKOTAS AND SOUTHERN CANADA WITHIN SURFACE HIGH PRESSURE LOOKS DELAYED SOMEWHAT. THE COLDEST AIR...HOWEVER...STILL RESIDES OVER NORTHERN SASKATCHEWAN AND IS POISED TO ARRIVE LATE TOMORROW AFTERNOON. TEMPERATURES AND WIND CHILL VALUES ARE THE MAIN FORECAST CONCERNS IN THE SHORT TERM AS ARCTIC AIR RETURNS. TONIGHT...THE ARCTIC FRONT WILL SHIFT EAST ACROSS CENTRAL AND SOUTHERN GREAT LAKES WHERE A BAND OF SNOW WILL OCCUR. NORTHWEST OF THE FRONT...ARCTIC HIGH PRESSURE WILL BE BUILDING SOUTHEAST INTO THE REGION...AND PUSHING IN INCREASING AMOUNTS OF DRIER AIR IN THE LOW LEVELS. THIS DRY AIR SHOULD HELP ERODE MUCH OF THE LOW CLOUD COVER BY THE START OF THE EVENING. WITH WINDS A LITTLE TOO WESTERLY FOR MUCH OF A LAKE EFFECT COMPONENT ACROSS THE SNOW BELTS...THE ONLY CLOUD COVER WILL BE A BAND OF MID AND HIGH CLOUDS AS UPPER LEVEL FLOW WILL REMAIN OUT OF THE SOUTHWEST WHICH WILL KEEP SKIES PARTLY TO MOSTLY CLOUDY. IN REGARDS TO TEMPERATURES...WNW WINDS WILL BE COLD ADVECTING THROUGH THE NIGHT WITH 850MB TEMPS DROPPING TO 23 BELOW OVER N-C WISCONSIN. TEMPS LAST NIGHT OVER NORTHERN MINNESOTA WERE ONLY IN THE SINGLE DIGITS ABOVE AND BELOW ZERO...SO AM CONCERNED ABOUT DROPPING TEMPS TOO MUCH. NOT CONFIDENT OF DECOUPLING OCCURRING...SO WILL GO WITH LOWS AROUND IN THE NEG TEENS BELOW ZERO OVER CENTRAL AND NORTH-CENTRAL WISCONSIN TO THE SINGLE DIGITS ABOVE ZERO ALONG THE LAKE SHORE. AS MENTIONED ABOVE...THE BITTERLY COLD AIR LOOKS TO BE DELAYED BY A FEW HOURS...AND MAY NOT REACH WIND CHILL ADVISORY CRITERIA UNTIL 03Z OVER THE WESTERN FORECAST AREA. WITH COORD FROM FORECAST OFFICES TO THE WEST...WILL DELAY THE START TIME OF THE WESTERN ADVISORY UNTIL 03Z. THE EAST WILL START AT 06Z AS PLANNED. SUNDAY...SKIES WILL CONTINUE TO BE PARTLY TO MOSTLY CLOUDY WITH MID HIGH CLOUDS OVERHEAD. SHOULD SEE THESE CLOUDS DEPART TO THE SOUTHEAST BY LATE MORNING OR EARLY AFTERNOON. THEN A LOBE OF THE POLAR VORTEX WILL SWING SOUTHEAST INTO THE NORTHERN MISSISSIPPI VALLEY DURING THE AFTERNOON. A SECONDARY SURGE OF ARCTIC AIR WILL ARRIVE WITH THE POLAR VORTEX...AND TEMPS MAY START THEIR FALL BY MID-AFTERNOON. OFTEN WITH THE LEADING EDGE OF THESE BITTERLY COLD AIRMASSES THERE ARE SCT INSTABILITY SNOW SHOWERS AND MODELS ARE SHOWING HIGHER LOW LEVEL MOISTURE INCOMING TOMORROW AFTERNOON. NOT SURE IF THIS WILL OCCUR IN THIS CASE SINCE THERE IS NO DEFINED ARCTIC FRONT...BUT DID SHOW INCREASING CLOUDS LATE IN THE AFTERNOON. ANOTHER THING TO KEEP TABS ON IS THE NORTHERN EXTENT OF THE PRECIP TOMORROW AFTERNOON WITH WITH THE CYCLONE MOVING OVER THE OHIO VALLEY. BOTH THE NAM AND GEM BRING LIGHT PRECIP INTO FAR E-C WISCONSIN IN THE AFTERNOON...BUT THIS LOOKS TOO FAR INTO THE ARCTIC AIRMASS. WILL LEAVE POPS OUT. WITH THE FALLING TEMPS IN THE AFTERNOON...WIND CHILLS WILL BE APPROACHING WARNING CRITERIA OVER CENTRAL AND NORTH-CENTRAL WISCONSIN BY 00Z MON. .LONG TERM...SUNDAY NIGHT THROUGH SATURDAY ISSUED AT 221 PM CST SAT JAN 4 2014 PROGS STILL PASS THE CORE OF THE POLAR VORTEX OVER THE REGION SUNDAY NIGHT INTO MONDAY BEFORE LIFTING EASTWARD INTO TUESDAY. STRONG BAROCLINIC ZONE IN THE LEAD ARCTIC SURFACE FRONT POSITIONED TO THE SOUTH AND EAST OF THE AREA LATE SUNDAY WILL BE THE FOCUS OF ANOTHER SURFACE WAVE AND A REGION OF SNOW EARLY SUNDAY EVENING. WHILE THE GFS KEEPS THIS AREA OF SNOW SOUTH OF THE AREA SUNDAY EVENING...THE NAM LIFTS THE NORTHERN PERIPHERY OF THIS SNOW INTO PARTS OF EAST CENTRAL WISCONSIN. FOR THIS SCENARIO TEMPS WOULD BE A FEW DEGREES WARMER...BUT WINDS WOULD BE STRONGER DUE TO THE LOCATION OF THE SURFACE WAVE AND PRESSURE GRADIENT. REGARDLESS OF EITHER SCENARIO...LITTLE CHANGE TO GOING EXTREME COLD WIND CHILL FORECASTS...SO NO CHANGES TO THE GOING WIND CHILL WARNING HEADLINES STARTING SUNDAY EVENING. FOR THE REST OF THE MODELS CONCERNING THIS LIGHT SNOW POTENTIAL SUNDAY EVENING FOR THE LAKESHORE REGION...THE GEM AND ECMWF ALSO PRODUCE SOME LIGHT SNOW ALONG THE LAKE SHORE REGION IN THE EVENING HOURS. PERHAPS THE MODELS ARE PICKING UP A TREND OF A CONVERGENT REGION DEVELOPING ON THE WEST SIDE OF LAKE MICHIGAN DUE TO THE STRONGER WINDS ON THE LAKE PULLING AWAY FROM THE AREA. SURFACE PRESSURE PLOTS SUGGEST A SUBTLE HEIGHT FALL OVER LAKE MICHIGAN AS WELL. INCREASING UNSTABLE CONDITIONS OVER THE LAKE ALSO DEVELOPING WITH THE POLAR VORTEX AND BAROCLINIC ZONE APPROACHING. WILL ADD A SMALL CHANCE FOR SNOW SHOWERS FOR NOW..BUT ITS POSSIBLE THIS MAY NEED TO BE INCREASED A LITTLE. UPPER PATTERN GRADUALLY TURNS MORE ZONAL MID WEEK FOR A TURN TO MORE NORMAL CONDITIONS. A PIECE OF SOUTHERN STREAM ENERGY SLIDES OVER THE MID MISSISSIPPI VALLEY REGION WEDNESDAY NIGHT INTO THURSDAY AND ALONG THE H850 FRONTAL BOUNDARY...GLANCING THE SOUTH HALF OF THE FORECAST REGION WITH LIGHT SNOW. ANOTHER SHORT WAVE TROUGH MAY SLIDE OVER THE GREAT LAKES REGION FRIDAY NIGHT INTO SATURDAY FOR ANOTHER CHANCE OF SNOW OR SNOW MIX...OTHERWISE THE DRIER WESTERLY OR PACIFIC FLOW CONTINUES INTO THE WEEKEND WITH MODERATING DAY TIME HIGH TEMPERATURES APPROACHING THE LOWER 30S WITH NO MAJOR WEATHER SYSTEMS NOTED AT THIS TIME. && .AVIATION...FOR 06Z TAF ISSUANCE ISSUED AT 1010 PM CST SAT JAN 4 2014 ARCTIC AIR WL BE OVERSPREADING THE AREA DURING THE NEXT 24 HRS. LOW-LEVEL SUBSIDENCE WL GENERATE VFR CONDITIONS TNGT. EXPECT INCREASING WINDS TOMORROW AFTN AS WAVE RIDES NEWD ALONG THE ARCTIC FRONT TO OUR E. LOWER CLDS AND SOME FLURRIES EXPECTED BY LATE SUN AFTN. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL WARNING FROM 6 PM SUNDAY TO NOON CST TUESDAY FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. WIND CHILL ADVISORY FROM 6 AM TO 6 PM CST SUNDAY FOR WIZ013-020- 021-031-037>039-045-048-049-073-074. WIND CHILL ADVISORY UNTIL 6 PM CST SUNDAY FOR WIZ005-010>012-018- 019-030-035-036. && $$ UPDATE.........SKOWRONSKI SHORT TERM.....MPC LONG TERM......TDH AVIATION.......SKOWRONSKI
AREA FORECAST DISCUSSION
NWS ALBANY NY
1008 AM EST SUN JAN 5 2014 .SYNOPSIS... A STORM WILL ORGANIZE IN THE TENNESSEE VALLEY LATE SUNDAY AND TRACK TO THE SAINT LAWRENCE VALLEY MONDAY...BRINGING RAIN AND A WINTRY MIX OF PRECIPITATION TO THE REGION. BEHIND IT...ANOTHER FRIGID SURGE OF ARCTIC AIR WILL MOVE INTO OUR REGION AND LAST THROUGH THE MIDDLE OF THE WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... MAJOR CHANGES HAVE BEEN MADE TO THE GRIDDED DATABASE THROUGH EARLY THIS EVENING. GIVEN THAT THIS MORNING/S TEMPS DROPPED DOWN INTO THE SINGLE DIGITS ABOVE AND BELOW ZERO AREAWIDE...DESPITE SUNSHINE THROUGH MIDDAY...THE DEEP SNOWPACK ON THE GROUND AND VERY COLD START WILL GREATLY LIMIT THE ABILITY OF THE LOWER ATMOSPHERE TO WARM MUCH TODAY. HAVE LOWERED MAX TEMPS BY AT LEAST 5 DEGREES AREAWIDE...AND IN SOME PLACES BY AS MUCH AS 10 DEGREES. EXPECT MOST AREAS TO ONLY REACH THE 20S TO LOWER 30S...COLDEST FOR AREAS NORTH OF THE MOHAWK RIVER. THIS POSES AN INCREASING THREAT FOR FREEZING RAIN LATE THIS AFTERNOON ACROSS CENTRAL AND SOUTHERN AREAS...WHERE NO ADVISORY CURRENTLY IS IN EFFECT. HAVE SLOWED DOWN THE TIMING OF THE PRECIPITATION ONSET...UNTIL EARLY/MID AFTERNOON FOR SOUTHERN AREAS...AND LATE AFTERNOON OR EARLY EVENING FURTHER NORTH. AT THIS TIME...CAN NOT RULE OUT SOME FREEZING RAIN POTENTIAL...PERHAPS A LIGHT GLAZE...EVEN FOR SOUTHERN AREAS LATE THIS AFTERNOON...AS WELL AS FURTHER NORTH INTO THE CATSKILLS/SCHOHARIE VALLEY AND GREATER CAPITAL DISTRICT. WE MAY NEED TO ISSUE A FREEZING RAIN ADVISORY BY MIDDAY FOR THESE AREAS SHOULD TEMPS FAIL TO RISE MUCH...AND PRECIPITATION KEEPS EXPANDING NORTHWARD. THE CURRENT BAND OF LIGHT PRECIPITATION TO OUR SOUTH...ACROSS NJ...NYC METRO AND LI...APPEARS TO BE INDUCED BY A BURST OF ISENTROPIC LIFT ALONG THE 285 K SFC. THE RUC13 SEEMS TO BE HANDLING THIS SOMEWHAT REASONABLY WELL...AND SUGGESTS THAT THIS FORCING REMAINS MAINLY SOUTH AND EAST OF OUR CWA THROUGH AT LEAST MIDDAY...ALTHOUGH MAY THEN EXPAND NORTHWARD LATER THIS AFTERNOON. TRENDS WILL BE WATCHED. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... THIS WILL BE AN ACTIVE WEATHER PERIOD AS THE STORM PASSES BY WELL TO OUR WEST...BUT THE COLD FRONT ASSOCIATED WITH THIS SYSTEM WILL MOVE ACROSS THE REGION MONDAY MORNING AND BRING ANOTHER SURGE OF BITTERLY COLD ARCTIC AIR TO THE REGION MONDAY NIGHT THROUGH THE MIDDLE OF THE WEEK. THIS SCENARIO WILL RESULT IN TEMPS RISING TONIGHT ACROSS THE REGION AS THE SOUTHERLY FLOW INCREASES AHEAD OF THE COLD FRONT. BY SUNRISE MONDAY EXPECT TEMPS TO BE IN THE MID 30S TO MID 40S ACROSS THE FORECAST AREA...WHICH WILL ALSO BE THE HIGH TEMP READING FOR MONDAY. ANY LEFTOVER MIXED PCPN EARLY TONIGHT WILL BECOME ALL RAIN IN ALL AREAS BY AROUND MIDNIGHT...WITH RAIN CONTINUING UNTIL THE FRONT PASSES THROUGH MONDAY MORNING. A PERIOD OF SNOW IS POSSIBLE BEHIND THE FRONT...ESPECIALLY OVER THE ADIRONDACKS AND WESTERN MOHAWK VALLEY WHERE AN INCH OR TWO COULD ACCUMULATE. ELSEWHERE...LITTLE MORE THAN A DUSTING TO HALF AN INCH MAY ACCUMULATE BEFORE PCPN ENDS. TEMPS WILL DROP DURING THE DAY...REACHING THE 20S AND LOWER 30S BY SUNSET. BY TUESDAY MORNING LOWS WILL BE IN THE 10 BELOW ZERO TO 10 ABOVE ZERO RANGE...THEN ONLY RISE SLIGHTLY TO HIGHS IN THE SINGLE DIGITS AND LOW TEENS ON TUESDAY. THE TEMPS FORECAST FOR MONDAY NIGHT AND TUESDAY ARE CONSIDERABLY LOWER THAN THOSE FORECAST BY THE MAV/MET MOS GUIDANCE PACKAGES...AND ARE MORE IN LINE WITH THE ECMWF MOS GUIDANCE. WESTERLY WINDS WILL BE QUITE GUSTY BEHIND THE FRONT WITH GUSTS OF 30 TO 35 MPH POSSIBLE MONDAY NIGH AND TUESDAY. HAVE ISSUED A WIND CHILL WATCH FOR AREAS WEST OF THE HUDSON VALLEY...INCLUDING NORTHERN WARREN COUNTY...WHERE WIND CHILL READINGS MAY DROP TO 30 BELOW ZERO OR LESS LATER MONDAY NIGHT INTO TUESDAY. ELSEWHERE...WIND CHILL READINGS SHOULD DROP TO ADVISORY LEVELS DURING THAT TIME PERIOD. THE FINAL SIGNIFICANT WEATHER CONCERN WILL BE A PROLONGED LAKE EFFECT EVENT ACROSS NORTHERN HERKIMER AND HAMILTON COUNTIES MONDAY NIGHT INTO WEDNESDAY...AND HAVE ISSUED A LAKE EFFECT SNOW WATCH FOR THOSE TWO ZONES. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... THE PERIOD STARTS OUT TUESDAY NIGHT WITH THE REGION STILL IN THE GRIP OF A BITTERLY COLD AIR MASS WITH A PERSISTENT WESTERLY BREEZE CONTINUING TO RESULT IN VERY LOW WIND CHILLS VALUES. ADDITIONAL WIND CHILL ADVISORIES FOR MUCH OF THE AREA...AND POSSIBLY SOME WARNINGS FOR THE CATSKILLS...MAY BE NEEDED TUESDAY NIGHT INTO WEDNESDAY MORNING. ALSO...LAKE EFFECT SNOW WILL BE ONGOING ACROSS THE WESTERN ADIRONDACKS. BASED ON THE EXPECTED QUASI-STATIONARY WESTERLY FLOW REGIME...NORTHERN HERKIMER AND HAMILTON COUNTIES LOOK TO CONTINUE TO RECEIVE ACCUMULATING SNOWFALL FROM THE RATHER LONG DURATION EVENT INTO WEDNESDAY. THE LAKE EFFECT SNOW WATCH WILL CONTINUE INTO WEDNESDAY. COLD TEMPERATURES WILL ALSO PERSIST ON WEDNESDAY...WITH HIGHS GENERALLY IN THE TEENS AND WESTERLY BREEZE CONTINUING. OUTSIDE OF LAKE EFFECT SNOW OVER THE WESTERN ADIRONDACKS...IT SHOULD REMAIN DRY ACROSS THE REST OF THE AREA. THE COLDEST AIR ALOFT WILL BE ERODING OVER THE AREA WITH A SLOW MODERATION EXPECTED THROUGH THE REST OF THE WEEK. THE NEXT CHANCE OF PRECIP ARRIVES THURSDAY NIGHT INTO EARLY FRIDAY...AS WARM ADVECTION/ISENTROPIC LIFT DEVELOPS ON THE BACK SIDE OF HIGH PRESSURE DEPARTING OFF THE NEW ENGLAND COAST. THERE IS UNCERTAINTY REGARDING QPF...AS GFS INDICATING RATHER HEFTY QPF FOR SUCH AN INNOCUOUS SYSTEM WITH NO ORGANIZED CYCLONE OR INTENSE BAROCLINIC ZONE. WE WOULD TEND TO FAVOR THE ECMWF DEPICTING LIGHTER QPF IN THIS CASE. SO WILL STILL ONLY MENTION CHANCE POPS AT THIS TIME WITH QPF EXPECTED TO BE ON THE LIGHTER SIDE. TEMPERATURE PROFILES LOOK COLD ENOUGH FOR ALL SNOW. ONCE THIS SYSTEM DEPARTS LATER FRIDAY...MODELS HAVE TRENDED DRIER FOR FRIDAY NIGHT INTO SATURDAY...AS RIDGING DEVELOPS TO OUR SOUTH AND OUR AREA GETS INTO A MILDER WESTERLY FLOW REGIME. AS A RESULT...HAVE LOWERED POPS TO SLIGHT CHANCE FOR THIS TIME FRAME. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... VFR CONDITIONS TO START THE PERIOD THIS MORNING...THEN STRATUS CLOUDS WILL INCREASE FROM SOUTH TO NORTH DURING THE AFTERNOON WITH MVFR CIGS. LIGHT PRECIP IS EXPECTED TO DEVELOP LATE THIS AFTERNOON INTO THIS EVENING...AS MOISTURE INCREASES AHEAD OF A LOW PRESSURE SYSTEM TRACKING FROM THE OHIO VALLEY INTO THE EASTERN GREAT LAKES. CONDITIONS WILL EVENTUALLY DETERIORATE TO IFR DURING THE EVENING AS STEADIER PRECIP DEVELOPS. PRECIP TYPE EXPECTED TO BE PLAIN FOR KALB/KPOU BUT THERE IS A LOW PROBABILITY FOR BRIEF FREEZING RAIN AT THE ONSET. SLEET/FREEZING RAIN EXPECTED AT KPSF INITIALLY BEFORE CHANGING TO RAIN...WHILE KGFL WILL HAVE SURFACE TEMPS AT OR BELOW FREEZING UNTIL LATE TONIGHT...AND THUS FREEZING RAIN EXPECTED THERE THROUGH 08Z MONDAY BEFORE CHANGING TO RAIN. WINDS WILL BE VARIABLE AROUND 5 KT OR LESS INTO THIS EVENING...THEN WILL GENERALLY SHIFT TO THE SOUTHEAST AT 5-10 KT. LOW LEVEL WIND SHEAR WILL DEVELOP BY THIS EVENING AS A SOUTHERLY JET MOVES OVERHEAD WITH 50 KT OF WIND AT 1500 FT AGL. OUTLOOK... MONDAY: HIGH OPERATIONAL IMPACT. BREEZY. DEFINITE RA...SN. MONDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX. TUESDAY: MODERATE OPERATIONAL IMPACT. WINDY. NO SIG WX. TUESDAY NIGHT: LOW OPERATIONAL IMPACT. BREEZY. NO SIG WX. WEDNESDAY TO WEDNESDAY NIGHT: NO OPERATIONAL IMPACT. NO SIG WX. THURSDAY: LOW OPERATIONAL IMPACT. SLIGHT CHANCE OF SN. THURSDAY NIGHT: MODERATE OPERATIONAL IMPACT. CHANCE OF SN. FRIDAY: MODERATE OPERATIONAL IMPACT. CHANCE OF SHSN. && .HYDROLOGY... NO WIDESPREAD HYDROLOGIC PROBLEMS ARE EXPECTED OVER THE NEXT FIVE DAYS. A STORM WILL ORGANIZE IN THE TENNESSEE VALLEY LATE SUNDAY AND TRACK TO THE SAINT LAWRENCE VALLEY MONDAY...BRINGING RAIN AND A WINTRY MIX OF PRECIPITATION. BEHIND IT ANOTHER FRIGID SURGE OF ARCTIC AIR WILL MOVE INTO OUR REGION AND LAST THROUGH MID WEEK. WHILE THERE EXISTS SOME UNCERTAINTY OF TIMING AND PTYPE...EXPECT ONLY MINOR IMPACTS ON THE RIVERS...EVEN IN AREAS WHERE MOSTLY RAIN FALLS. THE SNOW COVER SHOULD BE ABLE TO ABSORB MUCH OF THE RAINFALL...AND TEMPERATURES IN THESE AREAS WILL BE ABOVE FREEZING FOR ONLY ABOUT 24 HOURS. DURING THE MID WEEK PERIOD ICE ON THE RIVERS WILL BECOME THICKER AS ANOTHER COLD AIRMASS SETTLES OVER OUR REGION. FOR DETAILS ON SPECIFIC AREA RIVERS AND LAKES...INCLUDING OBSERVED AND FORECAST RIVER STAGES AND LAKE ELEVATIONS...PLEASE VISIT THE ADVANCED HYDROLOGIC PREDICTION SERVICE /AHPS/ GRAPHS ON OUR WEBSITE. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...NONE. NY...WIND CHILL WATCH FROM LATE MONDAY NIGHT THROUGH TUESDAY AFTERNOON FOR NYZ032-033-038>040-042-047-048-051-058-063- 082. WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST MONDAY FOR NYZ032-033-038>043-082>084. LAKE EFFECT SNOW WATCH FROM MONDAY EVENING THROUGH WEDNESDAY AFTERNOON FOR NYZ032-033. MA...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST MONDAY FOR MAZ001-025. VT...WINTER WEATHER ADVISORY FROM 4 PM THIS AFTERNOON TO 6 AM EST MONDAY FOR VTZ013>015. && $$ SYNOPSIS...KL/GJM NEAR TERM...KL/GJM SHORT TERM...GJM LONG TERM...JPV AVIATION...JPV HYDROLOGY...11
AREA FORECAST DISCUSSION
NWS TALLAHASSEE FL
1043 AM EST Sun Jan 5 2014 .NEAR TERM [Rest of Today]... Some cloud cover is expected to linger through much of the day, with mostly cloudy skies likely in most locations by sunset. This should keep temperatures relatively cool, especially across our far western and northern areas where low stratus may be more persistent. Highs were tweaked down slightly into the upper 50s in those areas. It should be a fairly warm day elsewhere with highs near or slightly above normal values. Enjoy the relatively warm day, as the cold air arrives late tonight and tomorrow morning! Although daytime PoPs remain concentrated over the water, we did add some isolated sprinkles to the rest of the area during the daytime as the HRRR and local TAE WRF-ARW both show a scattering of light echoes on simulated reflectivity through the day. && .PREV DISCUSSIONS [550 AM EST]... SHORT TERM [Tonight Through Tuesday]... Overall, there was little change to the previous forecast. Guidance is still heavily clustered around very cold temperatures and wind chills across the area as an Arctic front moves through the area. The front will move through the western areas late tonight and the remainder of the area early Monday, bringing with it the coldest airmass we have felt in a long time given the expected combination of temperature and wind. The recently issued freeze warning, hard freeze watch, wind chill watch, and gale watch contain the details of the expected impacts of this event. LONG TERM [Tuesday Night Through Saturday]... Tuesday night will likely see another hard freeze over most of the area, although winds will be lighter so the wind chill will not be as low as Monday night. As the high pressure pushes off the east coast Wednesday through Thursday, winds will shift to the east and then south and once again return warmer, moist air to the region. As an upper level disturbance propagates through otherwise mostly zonal flow and develops another mid and upper level trough, another cold front will begin to develop and then move across our area later next week. Chances for rain increase through the weekend, with widespread chances (30-50%) Friday through Saturday. AVIATION... [Through 12Z Monday] Very complex and challenging aviation fcst over the next 24 hrs, as much of the model guidance did very poorly overnight. However, this was generally a positive development for the individual terminals, as the "gloom and doom" fcst suggested by many of the models and guidance never did materialize. Although ABY and VLD have finally reached low end MVFR level CIGS with still the possibility of a brief period of IFR level conditions, TLH, ECP, and DHN have been mired in VFR level CIGS which was quite an improvement over guidance. While these CIGS may not break out much (or at all) during the day today, am leaning towards improving ABY and VLD back up to VFR levels for some period of time this afternoon. For later tonight and early Monday morning, we could see somewhat similar results, although the probabilities for more widespread MVFR and IFR conditions do appear likely before the passage of the Arctic cold front. MARINE... Conditions will rapidly deteriorate late tonight as a strong, Arctic cold front crosses the region. Frequent gale force gusts out of the northwest are a possibility behind this front through the day on Monday over the western two-thirds of the area, so a gale watch has been posted. Winds will likely remain at least 20 knots through Tuesday afternoon, and exercise caution conditions will FIRE WEATHER... No fire weather concerns are expected for both today and Monday, and although extremely low dewpoints are expected on Tuesday, these will likely be offset by very low afternoon temperatures and other parameters which will not be compatible with Red Flag conditions. Therefore, although Tuesday afternoon does bear watching at this time, a Fire Weather Watch or Red Flag Warning is not anticipated. HYDROLOGY... Only the Apalachicola River at Blountstown remains in minor flood stage, and it is expected to slowly decline below flood stage by Tuesday morning. No additional flooding is expected this week. && .Preliminary Point Temps/PoPs... Tallahassee 69 44 44 20 38 / 10 40 10 0 0 Panama City 68 41 41 23 38 / 20 40 10 0 0 Dothan 58 31 35 15 31 / 10 40 10 0 0 Albany 59 39 39 15 32 / 10 40 10 0 0 Valdosta 64 50 50 20 36 / 10 40 30 10 0 Cross City 74 62 62 22 41 / 10 30 30 10 0 Apalachicola 65 46 46 24 38 / 20 40 10 0 0 && .TAE Watches/Warnings/Advisories... FL...Hard Freeze Watch from Monday evening through Tuesday morning for Calhoun-Coastal Bay-Coastal Dixie-Coastal Franklin- Coastal Gulf-Coastal Jefferson-Coastal Taylor-Coastal Wakulla-Gadsden-Inland Bay-Inland Dixie-Inland Franklin- Inland Gulf-Inland Jefferson-Inland Taylor-Inland Wakulla- Lafayette-Leon-Liberty-Madison-South Walton. Freeze Warning from 4 AM to Noon CST Monday for Central Walton- Holmes-Inland Walton-Jackson-Washington. Hard Freeze Watch from Monday afternoon through Tuesday afternoon for Central Walton-Holmes-Inland Walton-Jackson- Washington. GA...Hard Freeze Watch from Monday evening through Tuesday morning for Ben Hill-Berrien-Brooks-Colquitt-Cook-Decatur-Grady- Irwin-Lanier-Lowndes-Mitchell-Thomas-Tift-Turner-Worth. Wind Chill Watch from late Monday night through Tuesday morning for Baker-Ben Hill-Berrien-Calhoun-Clay-Colquitt-Cook- Dougherty-Early-Irwin-Lanier-Lee-Miller-Mitchell-Quitman- Randolph-Terrell-Tift-Turner-Worth. Freeze Warning from 5 AM to 1 PM EST Monday for Baker-Calhoun- Clay-Dougherty-Early-Lee-Miller-Quitman-Randolph-Seminole- Terrell. Hard Freeze Watch from Monday afternoon through Tuesday afternoon for Baker-Calhoun-Clay-Dougherty-Early-Lee-Miller- Quitman-Randolph-Seminole-Terrell. AL...Wind Chill Watch from late Monday night through Tuesday morning for Coffee-Dale-Geneva-Henry-Houston. Freeze Warning from 4 AM to Noon CST Monday for Coffee-Dale- Geneva-Henry-Houston. Hard Freeze Watch from Monday afternoon through Tuesday afternoon for Coffee-Dale-Geneva-Henry-Houston. GM...Gale Watch from Monday morning through Monday evening for Coastal waters From Ochlockonee River to Apalachicola FL out to 20 NM-Coastal waters from Apalachicola to Destin FL out 20 NM-Waters from Suwannee River to Apalachicola FL from 20 to 60 NM-Waters from Apalachicola to Destin FL from 20 to 60 NM. && $$ NEAR TERM...LAMERS SHORT TERM...DVD LONG TERM...CAMP/DVD AVIATION...GOULD MARINE...DVD FIRE WEATHER...GOULD HYDROLOGY...DVD
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
943 AM EST SUN JAN 5 2014 .UPDATE... THE NEAR TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 319 AM EST SUN JAN 5 2014 A STORM SYSTEM IS EXPECTED TO BRING A SIGNIFICANT WINTER STORM TO THE AREA TODAY AND TONIGHT...FOLLOWED BY VERY COLD AIR EARLY NEXT WEEK IN THE WAKE OF THIS STORM. ADDITIONAL FRONTAL SYSTEM MAY AFFECT THE AREA AROUND THE MIDDLE OF THE WEEK AND OVER NEXT WEEKEND. && .NEAR TERM /REST OF TODAY AND TONIGHT/... ISSUED AT 943 AM EST SUN JAN 5 2014 CURRENT FORECAST IS ON TRACK. PRECIPITATION HAS OVERSPREAD THE AREA...WITH MODERATE SNOW ACROSS NORTHWEST 2/3 OF CENTRAL INDIANA. ACROSS THE REMAINDER OF THE AREA...A MIX OF RAIN AND SNOW OR JUST RAIN CONTINUES. DUAL-POL RADAR SHOWING MIXED PRECIPITATION IS MOVING NORTH AS EXPECTED. RAP TRIES TO BRING MIX AS FAR NORTH AS INDIANAPOLIS BUT LATEST NAM12 KEEPS IT JUST SOUTHEAST OF INDY. BASED ON EXPECTED PATH OF LOW AND CURRENT TRENDS... LEFT FORECAST AS IS WITH MIX COMING AS FAR NORTH AS SHELBYVILLE/RUSHVILLE. WILL MONITOR CLOSELY. PREVIOUS DISCUSSION FOLLOWS... THINGS SEEM TO BE EVOLVING SLOWER THAN EXPECTED...BUT MODEL DATA SUGGEST THE MAIN THEME REMAINS THE SAME. MODELS IN RATHER GOOD AGREEMENT NOW WITH RESPECT TO THE DEVELOPING SURFACE LOW...TRACKING IT NEAR OF JUST SOUTH OF THE OHIO RIVER THIS AFTERNOON AND EVENING. NOT TOO MUCH GOING ON AT THIS TIME...HOWEVER THE MAIN LIFT FROM THIS STORM IS EXPECTED TO BEGIN MOVING INTO THE AREA AFTER SUNRISE...SO EXPECTING PRECIPITATION TO INCREASE IN INTENSITY/COVERAGE BY THAT TIME. THE STRONGEST LIFT/HEAVIEST PRECIPITATION LOOKS TO PASS OVER THE AREA FROM ABOUT MIDDAY THROUGH THE AFTERNOON HOURS. SOME LINGERING WARM AIR OVER THE SOUTH/SOUTHEAST ZONES SHOULD RESULT IN MORE OF A MIX INTO THE AFTERNOON HOURS BEFORE THE ATMOSPHERIC COLUMN COOLS. ELSEWHERE...PRECIPITATION TYPE EXPECTED TO REMAIN SNOW. MODEL DATA SUGGEST DEFORMATION ZONE WILL STILL BE OVER THE WESTERN ZONES BY EVENING...SO THINK LIGHTER SNOWFALL WILL CONTINUE OVER THE AREA THROUGH ABOUT MIDNIGHT BEFORE TAPERING OFF TO SNOW SHOWERS AND FLURRIES. WINDS EXPECTED TO PICK UP TOWARDS/AFTER SUNSET TONIGHT WITH GUST TO AROUND 40 MPH POSSIBLE. THIS WILL CAUSE CONSIDERABLE BLOWING AND DRIFTING SNOW. MAY FLIRT WITH BLIZZARD CRITERIA FOR A PERIOD THIS EVENING...BUT WITH THE HEAVIER SNOW DIMINISHING BY THAT TIME...MAY BE HARD TO REACH VISIBILITY CRITERIA. THIS WILL BE SOMETHING THAT WILL NEED TO BE WATCHED. GIVEN A SURFACE LOW TRACK ALONG THE OHIO RIVER AND LOCATION OF DEFORMATION ZONE...STILL APPEARS THE HIGHEST STORM TOTALS WILL BE LOCATED OVER THE NORTHWEST HALF OF THE FORECAST AREA...WITH LESSER TOTALS FARTHER SOUTHEAST DUE TO MIXING ISSUES AND BEING LOCATED FARTHER AWAY FROM THE DEFORMATION ZONE. MODEL GUIDANCE SUGGESTS POTENTIAL STORM TOTALS FROM AROUND 5 INCHES OVER THE FAR SOUTHEAST TO ABOUT 10 TO 14 INCHES OVER THE NORTHWEST HALF OF THE AREA. WILL HOLD ONTO THE WINTER STORM WARNING AS IS FOR NOW...ALTHOUGH IT DOES APPEAR CONDITIONS WON/T BEGIN TO DETERIORATE UNTIL AFTER SUNRISE. DUE TO THE SLOWER EVOLUTION OF THE STORM...MAY NEED TO EXTEND THE WARNING LATER IN TIME AS WELL. WILL ALSO BE ISSUING A WIND CHILL WARNING STARTING LATE TONIGHT AND LASTING THROUGH TUESDAY WITH WIND CHILLS EXPECTED TO EXCEED WARNING CRITERIA THROUGHOUT THOSE TIMES. EXPECTING TEMPERATURES TO HOLD ABOUT STEADY UNTIL PRECIPITATION BEGINS...THEN SLOWLY FALL OFF DURING THE AFTERNOON. THE SLOWER EVOLUTION OF THE STORM SUGGESTS TEMPERATURES PROBABLY WON/T REALLY START FALLING ON UNTIL AFTER SUNSET. BASED ON LOW LEVEL THICKNESSES...THE GFS MOS LOWS TONIGHT LOOK TOO COLD. WILL BUMP THEM UP ABOUT 3-5 DEGREES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... ISSUED AT 319 AM EST SUN JAN 5 2014 DEEP COLD UPPER LOW OVER THE GREAT LAKES ON MONDAY EXPECTED TO REMAIN PROGRESSIVE...SO VERY COLD TEMPERATURES SHOULD GRADUALLY MODERATE DURING THE PERIOD AS HEIGHTS SLOWLY RISE. OTHER THAN SOME FLURRIES ON MONDAY DUE TO VERY STEEP LOW LEVEL LAPSE RATES...THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE MOVES THROUGH. LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS HIGHS AND LOWS MONDAY AND MONDAY NIGHT LOOK A LITTLE TOO COLD. WILL RAISE THE GUIDANCE SEVERAL DEGREES IN THOSE PERIODS. HIGHS BY TUESDAY LOOK BETTER...BUT MAY STILL BE A LITTLE COLD. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... ISSUED AT 334 AM EST SUN JAN 5 2014 ACTIVE PATTERN CONTINUES THROUGH THE PERIOD...WITH YET ANOTHER CHANCE FOR ACCUMULATING SNOW BEGINNING LATE WEDNESDAY AS AN UPPER LEVEL WAVE DROPS SOUTHEAST OUT OF THE NORTHERN PLAINS AND INTERACTING WITH A SURFACE TROUGH AND GULF MOISTURE LIFTING NORTH INTO THE REGION. THIS FEATURE WILL LIFT SLOWLY THROUGH THE OHIO VALLEY WITH SNOW LIKELY TO FALL WEDNESDAY NIGHT AND THURSDAY... POSSIBLY CONTINUING INTO THURSDAY NIGHT. STILL A BIT PREMATURE TO CONSIDER SPECIFIC ACCUMS AT THIS POINT BUT IT DOES APPEAR THE POTENTIAL WILL EXIST FOR A FEW INCHES OF SNOW AT THE VERY LEAST. UPPER LEVEL FLOW WILL TRANSITION FROM QUASI-ZONAL TO A MOIST SOUTHWEST FLOW BY FRIDAY AS AN UPPER LEVEL LOW DEVELOPS OVER NORTHERN MEXICO. ANOTHER STORM SYSTEM SET TO DEVELOP AND EXPAND TOWARDS THE OHIO/TENNESSEE VALLEYS OVER THE WEEKEND AS THE UPPER LOW EJECTS INTO TEXAS BY SUNDAY. APPEARS ENOUGH WARM AIR WITHIN THE LOWER LEVELS WILL ADVECT NORTH TO PRESENT A WINTRY PRECIP MIX OR EVEN A PERIOD WITH RAIN AS THE PREDOMINANT PRECIP TYPE. HIGHS SHOULD WARM BACK INTO THE 30S TO LOWER 40S BY SATURDAY AND SUNDAY...LIKELY TO BE A WELCOME CHANGE FROM THE BITTERLY COLD TEMPS TO COME OVER THE NEXT FEW DAYS. && .AVIATION /DISCUSSION FOR THE 051500Z KIND TAF UPDATE/... ISSUED AT 930 AM EDT SUN JAN 5 2014 MINOR TWEAKS MADE TO KIND TAF TO BETTER MATCH CURRENT CONDITIONS. NO OTHER CHANGES NEEDED AT THIS TIME. PREVIOUS AVIATION DISCUSSION FOLLOWS... RAPIDLY DETERIORATING WEATHER WILL CREATE EXTREMELY POOR FLYING CONDITIONS THROUGHOUT THE FORECAST PERIOD. PRECIPITATION RAPIDLY EXPANDING INTO THE FORECAST AREA EARLY THIS MORNING...WITH SNOW NOW FALLING AT ALL TERMINALS. SNOW WILL BECOME WIDESPREAD AND GRADUALLY HEAVIER AS THE DAY PROGRESSES AS A COLD FRONT SAGS INTO THE REGION AND LOW PRESSURE OVER ARKANSAS THIS MORNING TRACKS ALONG THE BOUNDARY INTO THE OHIO VALLEY THIS AFTERNOON. AS THE LOW APPROACHES LATER TODAY...MODEL SOUNDINGS INDICATING WARMER AIR WITHIN THE BOUNDARY LAYER WILL BE DRAWN INTO SOUTHERN INDIANA...POSSIBLY ALLOWING FOR RAIN TO MIX WITH THE SNOW OR EVEN SLEET/FREEZING RAIN FOR A BRIEF PERIOD. THE ONLY TERMINAL EXPECTED TO BE IMPACTED BY THE MIXED PRECIP IS KBMG AND HAVE CONTINUED WITH RAIN/SNOW FROM LATE MORNING THROUGH MID AFTERNOON. THE WARMER AIR COMES CLOSE ENOUGH TO KIND THAT A VERY BRIEF PERIOD WITH SLEET MIXING IN WITH THE SNOW IS NOT ENTIRELY OUT OF THE QUESTION. CONFIDENCE IS TOO LOW TO MENTION AT THIS POINT BUT WILL NEED TO MONITOR. AS COLDER AIR RUSHES IN BEHIND THE BOUNDARY BY LATE AFTERNOON...PRECIP WILL CHANGE TO ALL SNOW AT KBMG. SNOW WILL BECOME HEAVIEST ACROSS CENTRAL INDIANA THIS AFTERNOON AS FORCING ALOFT INTENSIFIES AHEAD OF THE LOW. UNDER THE HEAVIEST BANDS...SNOWFALL RATES OF 1-2 INCHES PER HOUR ARE POSSIBLE. WILL INTRODUCE 1/4SM AND +SN AT ALL BUT KBMG FROM MID AFTERNOON INTO THE EVENING. WINDS WILL BECOME NORTHEAST BY MIDDAY THEN NORTH/NORTHWEST THIS AFTERNOON AS THE LOW PASSES TO THE SOUTH. AS THE LOW INTENSIFIES...WIND GUSTS TO AROUND 30KTS WILL DEVELOP BY LATE AFTERNOON. THIS WILL ALLOW FOR BLOWING SNOW IN ADDITION TO THE SNOWFALL TO DEVELOP AND CONTINUE THIS EVENING. THE LOW WILL TRACK INTO THE EASTERN GREAT LAKES TONIGHT...WITH SNOW COMING TO AN END AROUND MIDNIGHT. EVEN AS SNOW ENDS...THE STRONG WIND GUSTS WILL MAINTAIN BLOWING SNOW ALL NIGHT WITH REDUCED VISIBILITIES PERSISTING. CEILINGS WILL LIFT TO MFR OVERNIGHT...WITH SOME BREAKS DEVELOPING TOWARDS DAYBREAK MONDAY AS DRIER AIR SPREADS INTO THE REGION. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 AM EST MONDAY FOR INZ021-028>031- 035>049-051>057-060>065-067>072. WIND CHILL WARNING FROM 1 AM MONDAY TO 7 PM EST TUESDAY FOR INZ021-028>031-035>049-051>057-060>065-067>072. && $$ SYNOPSIS...JAS NEAR TERM...JAS/50 SHORT TERM...JAS LONG TERM....RYAN AVIATION...RYAN/JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
633 AM EST SUN JAN 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 448 AM EST SUN JAN 5 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP POLAR VORTEX CENTERED OVER SCENTRAL CANADA...WITH CORE OF ARCTIC AIRMASS ACCOMPANIED BY 00Z H5/H85/H925 TEMPS AS LO AS -43C/-31C/-34C AT THE PAS MANITOBA. UPR MI IS ON THE PERIPHERY OF THE VERY COLD AIRMASS ATTM...WITH 00Z H85 TEMPS RANGING FM -6C AT GRB TO -24C AT INL. LVL WNW FLOW TO THE E OF SFC HI PRES IN THE NRN PLAINS IS ADVECTING THE COLDER AIR INTO UPR MI...BUT RELATIVELY LIGHT WINDS HAVE SLOWED THE ADVECTION. THIS COLD FLOW OVER THE RELATIVELY WARM WATERS OF LK SUP IS CAUSING THE TYPICAL LK CLDS/LES IN THE FAVORED SN BELTS...BUT LO INVRN BASE ARND H9 AS SHOWN ON THE 00Z INL/GRB RAOBS AS WELL AS DRY NATURE OF THE LLVLS IS LIMITING THE INTENSITY OF THE SHSN. OTRW... QUITE A BIT OF HI CLD IS STREAMING OVER MAINLY THE SE HALF OF THE CWA WELL TO THE N OF SFC LO PRES DVLPG IN THE LOWER MS RIVER VALLEY. MAIN FCST CONCERNS THRU THE SHORT TERM FOCUS ON TEMPS/WIND CHILLS/ GOING HEADLINES AS WELL AS LES/BLSN. TODAY...THE CORE OF THE ARCTIC AIR OVER SCENTRAL CANADA EARLY THIS MRNG IS FCST TO DROP OVER MN BY 00Z MON. AS THE TROF OVER CENTRAL NAMERICA DEEPENS...THE SFC LO NOW OVER THE LOWER MS RIVER VALLEY IS PROGGED TO DEEPEN AND MOVE INTO THE OH RIVER VALLEY. ALTHOUGH THE LARGER SCALE FORCING/ASCENT/DEEP MOISTENING ASSOCIATED WITH THIS LO WL REMAIN TO THE E-SE OF UPR MI...THE PRES GRADIENT/LLVL NW FLOW OVER THE AREA IS FCST TO SHARPEN AND INCRS THE ADVECTION OF THE COLDER AIR INTO THE CWA. MODEL CONSENSUS SHOWS H85 TEMPS FALLING FM -23C OVER THE NW/-14C OVER THE SE AT 12Z TO -29C OVER THE NW/-19C OVER THE SE BY 00Z MON. AS A RESULT...THE DIURNAL TEMP RECOVERY... ESPECIALLY OVER THE WRN ZNS...WL BE NEGLIGIBLE. ALTHOUGH THE SURGE OF LLVL COLD AIR WL SUPPORT ONGOING LES...THE LO INVRN BASES ARND 3-4K FT AND ACYC NATURE OF THE H925 FLOW/GENERAL SUBSIDENCE WL LIMIT SN AMOUNTS...ESPECIALLY OVER THE W WHERE THE DGZ WL DESCEND INTO THE GROUND AND LIMIT SN GROWTH. THERE MAY BE AN UPTICK IN THE LES IN THE NW WIND SN BELTS E OF MQT LATER IN THE DAY HOWEVER AS LLVL CNVGC ON LK INDUCED TROF SHARPENS UNDER DEEPENING UPR TROF. AS FOR GOING WIND CHILL HEADLINES...OPTED TO DROP BARAGA...MARQUETTE AND DICKINSON COUNTIES FM THE HEADLINE GIVEN CURRENT CONDITIONS AND EXPECTATION THAT THESE AREAS WL NOT MEET CRITERIA MOST OF THE THE DAY. TONIGHT...THE LO TO THE SE IS PROGGED TO DEEPEN SGNFTLY AND LIFT NEWD INTO SE CANADA AS THE CENTRAL CONUS TROF SHARPENS WITH MORE PHASING OF THE ARCTIC AND POLAR BRANCHES. THE CORE OF THE COLDEST AIR...WITH H85 TEMPS DOWN TO -33C TO -35C...IS PROGGED TO SHIFT OVER WI. AS THE LO DEEPENS...THE PRES GRADIENT WL SHARPEN FURTHER OVER THE UPR LKS...ALLOWING H925 NW WINDS TO INCRS TO 25 TO 30 KTS. THE STRENGTHENING WINDS AND FALLING TEMPS SUPPORT GOING WIND CHILL WRNGS AWAY FM THE LK MODERATION THAT WL IMPACT MAINLY THE ERN CWA EVEN THOUGH A MORE N WIND COMPONENT OFF LK SUP MIGHT NOT ALLOW TEMPS TO FALL AS LO AS PREVIOUS FCST. BUT OVER THE ERN CWA...THE ARRIVAL OF DEEPER MSTR ASSOCIATED WITH ARRIVAL OF DEEP LYR QVECTOR CNVGC UNDER THE FALLING HGTS ASSOCIATED WITH THE DEEPENING UPR TROF AS WELL AS INCRSG LLVL CNVGC ACCOMPANYING THE SHARPENING OF THE LK INDUCED SFC TROF WL GIVE A BOOST TO THE LES. WITH MORE FVRBL SN GROWTH...H85 TEMPS ARE PROGGED TO FALL TO ARND -24C HERE BY 12Z MON...AS WELL AS INCRSG BLSN...OPTED TO REPLACE THE WIND CHILL ADVY FOR ALGER/LUCE/ SCHOOLCRAFT COUNTIES WITH A LK EFFECT SN ADVY TO ACCOUNT FOR SN FALL AT LEAST APRCHG ADVY AMOUNTS...BLSN AND WIND CHILLS AT LEAST APRCHG ADVY CRITERIA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 448 AM EST SUN JAN 5 2014 THE MAIN CONCERN FOR THE LONG TERM FORECAST WILL BE EXTREMELY COLD TEMPERATURES/WIND CHILLS AND REDUCED VISIBILITIES FROM LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW. LOW PRESSURE TRAVELING FROM THE OHIO VALLEY TODAY WILL REACH QUEBEC BY MONDAY MORNING. MEANWHILE...A COLD ARCTIC AIRMASS/HIGH PRESSURE WILL SINK FROM THE CANADIAN PRAIRIE INTO THE MIDWEST AND CENTRAL PLAINS. AS THIS HIGH SINKS TOWARDS THE GULF COAST MONDAY NIGHT...THE LOW OVER QUEBEC WILL DRIFT WESTWARD INTO JAMES BAY. THIS PATTERN WILL KEEP UPPER MICHIGAN IN A MODERATE WEST-NORTHWESTERLY FLOW THROUGH WEDNESDAY...AS A TIGHTER PRESSURE GRADIENT SITS OVER THE AREA. ADDITIONALLY...A 500MB LOW WILL CENTER ITSELF OVER UPPER MI MONDAY MORNING...THEN DRIFT SLOWLY NORTHEASTWARD INTO ONTARIO AND QUEBEC. WITH THE LOW CENTERED OVER UPPER MI 850-500MB QVECTOR CONVERGENCE IS MAXIMIZED OVER THE EASTERN U.P. AND LOWER MI. WITH NORTHWESTERLY WINDS MOVING THE COLD ARCTIC AIR OVER LAKE SUPERIOR...KEPT POPS IN NORTHWEST WIND FAVORED SNOWBELTS. ALSO INCREASED POPS IN THE EASTERN CWA AS THE UPPER LEVEL SUPPORT CROSSES THROUGH THE AREA WITH THE TROUGH. WINDS GENERALLY REMAIN NORTHWESTERLY THROUGH MONDAY AFTERNOON...THEN BEGIN TO BACK TOWARDS THE WEST-NORTHWEST WIND DIRECTION. ADJUSTED POPS ACCORDINGLY...WITH THE MAIN CORE OF PRECIPITATION IN THE EASTERN U.P. SHIFTING TO AREAS FAVORED BY WNW WINDS...MAINLY EAST OF MUNISING. ON TUESDAY SEVERAL SMALL SHORTWAVES SNEAK ALONG THE BASE OF THE TROUGH ALOFT AS IT MOVES EASTWARD...AND WNW WINDS BECOME MORE WESTERLY TOWARDS THE EVENING. MOST OF THE SNOW BY LATE TUESDAY AFTERNOON WILL BE OVER THE KEWEENAW AND EAST OF GRAND MARAIS. LIMITING FACTORS TO SIGNIFICANT ACCUMULATIONS WILL BE THE EXTREMELY COLD/DRY AIRMASS. THIS SENDS THE DGZ CRASHING INTO THE GROUND FOR MOST LOCATIONS...ESPECIALLY MONDAY NIGHT INTO TUESDAY AFTERNOON. AS A RESULT SNOW RATIOS WILL BE ON THE ORDER OF 15-18:1 AND FLAKES VERY FINE. AS FAR AS MOISTURE GOES...PWATS DURING THIS TIME FRAME DROP TO NEAR 15 PERCENT OF NORMAL FOR UPPER MI. OVERALL...FROM MONDAY MORNING THROUGH TUESDAY MORNING...HAVE 2-4 INCHES FOR AREAS FAVORED BY WEST-NORTHWEST WINDS. TUESDAY MORNING INTO WED MORNING ONLY HAVE 1-3 INCHES FOR THE SAME AREAS...MAINLY THE KEWEENAW AND EAST OF MUNISING NEAR LAKE SUPERIOR. THE COLD ARCTIC AIRMASS WILL BRING LOW TEMPERATURES CRASHING DOWN TO -27F OUT WEST...AND THE TEENS BELOW ZERO EAST FOR MONDAY NIGHT. AREAS NEAR THE LAKE WILL SEE TEMPERATURES DROP DOWN TO THE SINGLE DIGITS BELOW ZERO FARTHER EAST AND OVER THE KEWEENAW. WITH THE STRONGER WINDS OVER THE AREA HOWEVER...WIND CHILLS WILL DROP AS LOW AS -50F ACROSS THE WEST...AND MAINLY THE -30S AND -40S ELSEWHERE...EVEN NEAR THE LAKE. THOUGH SNOW ACCUMULATIONS WILL NOT BE HAZARDOUS BY THEMSELVES...THE COMBINATION OF SNOW...BLOWING SNOW...AND DANGEROUSLY LOW TEMPERATURES/WIND CHILLS WARRANT A LAKE EFFECT SNOW ADVISORY FOR AREAS IN THE EAST...MAINLY FOR ALGER/LUCE/SCHOOLCRAFT COUNTIES. WIND CHILLS WILL REACH ADVISORY CRITERIA...AND THE COMBINATION OF SNOW AND BLOWING SNOW/DUE TO WINDS AROUND 30 MPH/ WILL REDUCE VISIBILITIES DRAMATICALLY...ESPECIALLY WITH THE FINER FLAKES. ELSEWHERE...HAVE ONLY THE WIND CHILL WARNING IN EFFECT FOR THE MONDAY-TUESDAY TIME FRAME. THE KEWEENAW WILL ALSO SEE STRONG WINDS...GUSTING TO 25 TO 30 MPH...AND PERSISTENT LAKE EFFECT SNOW WITH AREAS OF BLOWING SNOW DURING THE MONDAY-TUESDAY TIME FRAME. HAVE INCLUDED THIS WORDING IN THE WIND CHILL WARNING FOR THE KEWEENAW/HOUGHTON COUNTIES FOR SIMPLICITY WITH HEADLINES. WINDS WILL GRADUALLY DIE DOWN FROM WEDNESDAY INTO THURSDAY AS THE HIGH CENTERS ITSELF OVER THE GREAT LAKES. LIGHT AND VARIABLE WINDS WILL GRADUALLY TRANSITION TO MORE MODERATE SOUTH TO SOUTHWESTERLY WINDS AS THE HIGH SHIFTS EASTWARD TOWARDS THE NEW ENGLAND STATES...AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA. SOME OF THE MODELS ATTEMPT TO BRING A WEAK SHORTWAVE TROUGH INTO THE MIDWEST LATE FRIDAY AFTERNOON AND SATURDAY...BUT OTHERS KEEP MORE ZONAL FLOW OVER THE AREA. WILL KEEP THE CONSENSUS POPS DURING THIS TIME FRAME HOWEVER...WITH THE WNW-LAKE EFFECT MOVING OUT INTO THE LAKE AS WINDS BACK TO THE SOUTH-SOUTHWEST. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z MONDAY MORNING) ISSUED AT 632 AM EST SUN JAN 5 2014 CMX...ALTHOUGH A LO INVRN BASE AND VERY DRY AIR WL LIMIT THE INTENSITY OF THE LK EFFECT -SHSN TODAY...EXPECT IFR CONDITIONS TO PREDOMINATE WITH OCNL MVFR VSBYS IN BTWN THE LES BANDS. WITH THE ARRIVAL OF DEEPER MSTR AND STRENGTHENING NW WINDS/MORE BLSN TNGT... VSBYS ARE LIKELY TO FALL INTO THE LIFR AND PERHAPS VLIFR RANGE MOST OF THE TIME. IWD...BACK EDGE OF LK EFFECT LO CLDS IS JUST TO THE SW OF THIS SITE EARLY THIS MRNG. AS THE LLVL WIND BACKS A BIT EARLY TODAY...THE MVFR CIG MAY BREAK AND GIVE WAY TO VFR CONDITIONS FOR AWHILE UNTIL THE AFTN...WHEN A VEERING WIND WL BRING THE LK CLDS BACK OVER THIS LOCATION. WITH THE ARRIVAL OF DEEPER MSTR AND STRENGTHENING WNW WINDS TNGT...EXPECT LK EFFECT -SHSN/SOME BLSN TO DROP VSBYS INTO THE IFR RANGE MOST OF THE TIME. SAW...EXPECT VFR CONDITIONS TO PREDOMINATE THRU THIS MRNG WITH A DOWNSLOPE WNW FLOW. MORE LK EFFECT CLDS WL ARRIVE THIS AFTN AS THE FLOW SLOWLY VEERS MORE TOWARD THE NW AND ALLOWS MORE LK SUP MODIFIED...MOISTER AIR TO FLOW OVER THIS SITE. ALTHOUGH THE LLVL NW WINDS WL NOT BE IDEAL...THE ARRIVAL OF DEEPER MSTR WL RESULT IN MORE -SHSN TNGT AND MORE SOLID MVFR CONDITIOSN. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 448 AM EST SUN JAN 5 2014 A GALE WATCH IS IN EFFECT FOR CENTRAL AND EASTERN LAKE SUPERIOR MONDAY MORNING THROUGH TUESDAY NIGHT...AND A HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT... EXPECT NW WINDS 20-25 KTS THIS MORNING TO INCREASE TO 25-30 KTS LATER TODAY AND TONIGHT AS THE PRES GRADIENT OVER THE UPPER GREAT LAKES SHARPENS TO THE NW OF A DEEPENING LO PRES MOVING NE THRU THE SE GREAT LAKES INTO SE CANADA. THERE MAY BE A FEW GALE FORCE GUSTS OVER PORTIONS OF THE E LAKE LATE TONIGHT AS WELL. WITH ARCTIC AIR PERSISTING OVER THE AREA...EXPECT PERIODS OF HEAVY FREEZING SPRAY... ESPECIALLY OVER THE E HALF WHERE WINDS WILL BE STRONGEST. LAKE SUPERIOR WILL BE CAUGHT THIS TIGHT PRESSURE GRADIENT BETWEEN STRONG ARCTIC HIGH PRESSURE OVER THE PLAINS AND STRONG LOW PRESSURE OVER QUEBEC MONDAY INTO TUESDAY. AS A RESULT...WEST NORTHWEST GALES TO 35 KNOTS WILL OCCUR OVER MAINLY CENTRAL AND EASTERN LAKE SUPERIOR ON MONDAY AFTERNOON...AND WEST NORTHWEST GALES TO 40 KNOTS WILL OCCUR ON TUESDAY AFTERNOON. WINDS ON WESTERN LAKE SUPERIOR WILL LARGELY REMAIN WEST-NORTHWEST AT 20 TO 30 KNOTS DURING THIS TIME. ADDITIONALLY...COLD ARCTIC AIR IN PLACE OVER LAKE SUPERIOR COMBINED WITH THE STRONG WINDS WILL LEAD TO HEAVY FREEZING SPRAY FOR ALL OF THE LAKE THROUGH WEDNESDAY MORNING. ON WEDNESDAY AND THURSDAY HIGH PRESSURE WILL MAKE ITS WAY NORTHWARD...CENTERING ITSELF OVER THE GREAT LAKES. AS A RESULT...GUSTY WEST NORTHWEST WINDS WILL DIE DOWN...EVENTUALLY BACKING SOUTHWEST AT LESS THAN 10 KNOTS BY THURSDAY. AS THE HIGH SHIFTS TO THE NEW ENGLAND STATES AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA FRIDAY AFTERNOON AND SATURDAY...SOUTHWESTERLY WINDS WILL PICK UP TO 15 TO 25 KNOTS OVER ALL OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 11 AM EST /10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084. WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR MIZ002-009-010-084. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST MONDAY FOR MIZ006-007-014-085. WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR MIZ006-007-014-085. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-243>245-248>251-263>267. GALE WATCH FROM MONDAY MORNING THROUGH LATE TUESDAY NIGHT FOR LSZ243>245-264>266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MCD AVIATION...KC MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
747 AM EST SUN JAN 5 2014 .SYNOPSIS... LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA LATER TODAY. A TRAILING ARCTIC COLD FRONT WILL SWEEP THROUGH PENNSYLVANIA EARLY MONDAY. UPPER LOW AND ASSOCIATED ARCTIC AIR MASS WILL LIFT OUT OF THE AREA LATER NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... BASED ON UPSTREAM OBS AND LATEST MDL OUTPUT...HAVE DELAYED ARRIVAL OF RA/ZR ACROSS THE AREA TODAY. FZRA REPORTED AT KBWI AT 10Z AND LATEST RAP SUGGESTS -FZRA COULD ENTER YORK/LANCASTER COS AFTER 12Z. WAA UNDERWAY EARLY THIS MORNING WITH 8H TEMPS ALREADY RISING ABV 0C ACROSS SOUTHERN PA AT 10Z. MEANWHILE...SFC TEMPS IN THE SINGLE DIGITS ACROSS MANY PARTS OF CENTRAL PA...CREATING A CLASSIC FZRA SOUNDING PROFILE. EXPECT WARMER AIR TO EVENTUALLY WIN OUT BY EARLY EVENING ACROSS THE EASTERN COUNTIES...AS WEAK SFC LOW LIFTING UP THE COASTAL PLAIN TRACKS ACROSS EASTERN PA. PER WWD GRAPHICS...EXPECT FZRA ACCRETION TO BE LESS THAN A TENTH OF AN INCH...BUT ENOUGH TO CREATE POTENTIAL TRAVEL PROBLEMS. BY EARLY EVENING...STEADIEST RAIN ASSOC WITH WEAK SFC LOW SHOULD BE EXITING THE EASTERN COUNTIES. MEANWHILE...LIGHTER -DZ/-FZDZ COULD LINGER OVR THE CENTRAL MTNS AND SUSQ VALLEY...WHERE SREF AND NAM INDICATE A POCKET OF LINGERING SFC TEMPS NR 32F. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... BATCH OF PRECIP ASSOC WITH WEAK COASTAL LOW SHOULD BE EXITING EASTERN PA EARLY THIS EVENING. MEANWHILE...PRIMARY SURFACE LOW WILL TRACK WEST OF PA TONIGHT...KEEPING CENTRAL PA IN THE WARM SECTOR FOR MUCH OF THE NIGHT. ANY POCKETS OF SUB-FREEZING AIR SHOULD BE SCOURED OUT OF THE VALLEYS DURING THE EVENING...AS DEEP SOUTHERLY FLOW OVERSPREADS THE REGION IN ADVANCE OF APPROACHING ARCTIC COLD FRONT. ALL MDL GUIDANCE INDICATES ARCTIC COLD FRONT WILL SWEEP THRU CENTRAL PA BTWN 06Z-12Z. A BAND OF GUSTY RAIN SHOWERS ARE LIKELY TO ACCOMPANY FROPA ALONG AXIS OF ANOMALOUS SOUTHERLY LL JET/PWATS. ARRIVAL OF MUCH COLDER AIR WILL TURN THE SHRA TO SHSN OVR THE W MTNS WITH A LIGHT ACCUM OF AN INCH OR SO POSSIBLE. THE WET GROUND...COMBINED WITH RAPIDLY FALLING TEMPS BLW FREEZING...COULD POTENTIALLY PRODUCE BLACK ICE/FLASH FREEZE CONDITIONS EARLY MON AM. LATER SHIFTS MAY NEED TO CONSIDER POSSIBLE WINT WX ADV. STRONG CAA WILL CAUSE TEMPS TO BUCK THE TYPICAL DIURNAL TREND WITH FALLING TEMPS THRU THE DAY. BY EARLY MONDAY EVENING...GEFS ENS MEAN 8H TEMPS FALL TO -26C...CLOSE TO 3SD BLW NORMAL. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... AIR MASS AS DEFINED BY 8H TEMPS COULD BE THE COLDEST THIS REGION HAS SEEN IN 20 YEARS. BY TUES AM...THE CORE OF THE COLD SHOULD LIE ACROSS SOUTHWEST PA...WHERE GEFS ENS MEAN 8H TEMPS FALL TO -30C. THE FRIGID TEMPS...COMBINED WITH WGUSTS ARND 30KTS MON NIGHT THRU TUESDAY WILL RESULT IN EXTREMELY DANGEROUS CONDITIONS...MAKING FROSTBITE AND HYPOTHERMIA A REAL CONCERN EVEN IF EXPOSED TO THE ELEMENTS FOR ONLY A SHORT PERIOD. HAVE EXPANDED THE WIND CHILL WATCH EASTWARD INTO THE RIDGE/VALLEY REGION...AS CONFIDENCE INCREASES THAT WARNING CRITERIA OF 25 BLW WILL BE REACHED. ALTHOUGH IT APPEARS UNLIKELY WE WILL RIVAL THE MIN TEMPS OF 1994...WIND CHILLS MAY BE AS COLD OR COLDER AS TIGHT PRES GRADIENT CONTINUES TO BUFFET THE AREA WITH GUSTS NR 30KTS INTO TUE EVENING. SIG LAKE EFFECT DOES NOT APPEAR TO BE A CONCERN...AS MDL DATA INDICATES BLYR FLOW WILL KEEP SNOW SHOWERS NORTH OF THE BORDER MON-WED. WEDNESDAY MORNING WILL ALSO BE VERY COLD...AS WINDS SLACKEN UPON ARRIVAL OF SFC HIGH. MODEL CONSENSUS SUPPORTS TEMPS SLOWLY MODERATING BACK TOWARDS NORMAL BY THE SECOND HALF OF THE WEEK. A LIGHT OVERRUNNING SNOWFALL IS POSSIBLE LATE WEEK...AS WARMER SW FLOW TRIES TO DISLODGE LINGERING LOW LVL CHILL ACROSS THE NORTHEAST CONUS. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... MAIN CHANGE TO THIS TAF PACKAGE IS TO DELAY BY SEVERAL HOURS THE ONSET OF LIGHT PRECIP AND LOWERING CIGS FOR MUCH OF THE AREA TODAY. WEAK DISTURBANCE SLIDING NORTHWARD THROUGH THE MID ATLANTIC REGION WILL PUSH LOW CLOUDS INTO CENTRAL PA FROM THE SOUTH THIS MORNING...WITH KLNS-KMDT-KJST DROPPING TO MVFR BY MID MORNING. A SWATH OF LIGHT FREEZING RA/DZ WILL ALSO DEVELOP OVER THE LOWER SUSQ DURING THE MID MORNING HOURS - PRODUCING SOME ICING CONDITIONS. AS SYSTEM LIFTS FURTHER NORTH THIS AFTERNOON...THE LOWER CIGS AND LIGHT FREEZING RAIN WILL IMPACT CENTRAL TERMINALS AS WELL. BY EARLY EVENING...DEEP SOUTHERLY FLOW FINALLY SCOURS OUT THE LOWER LEVELS AND WARMS TEMPS UP ENOUGH TO CHANGE PRECIP OVER TO PLAIN RAIN FOR MAJORITY OF CENTRAL PA LOCATIONS...BUT CIGS WILL CONTINUE TO LOWER TO IFR AS SYNOPTIC LIFT INCREASES WITH ARRIVAL OF DEEPENING LOW PRESSURE FROM THE OHIO VALLEY. THE WARMER AIR MOVING OVER THE SNOWPACK IN THE EAST WILL LIKELY GENERATE AN AREA OF THICKER FOG REDUCING VSBYS BELOW A MILE. LLWS INCLUDED IN TAFS AS 850 MB JET INCREASES TO 40-60 KTS. MODEL GUIDANCE INDICATES ARCTIC COLD FRONT WILL SWEEP THRU CENTRAL PA BETWEEN 06Z-12Z. A BAND OF GUSTY RAIN SHOWERS ARE LIKELY TO ACCOMPANY FROPA ALONG AXIS OF ANOMALOUS SOUTHERLY LL JET/PWATS. ARRIVAL OF MUCH COLDER AIR WILL TURN THE SHRA TO SHSN OVR THE W MTNS AND BEGIN A PERIOD OF STRONG AND GUSTY WESTERLY WINDS. OUTLOOK... MON...RESTRICTIONS IN THE MORNING...THEN IMPROVING CIGS /ESP SE HALF/ AS STRONG WESTERLY WINDS DEVELOP. TUE...SCT SNOW SHOWERS NW. VFR ELSEWHERE. WINDY. WED...SCT SNOW SHOWERS NW. VFR ELSEWHERE. THU...MVFR TO IFR WITH CHC LIGHT SNOW. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST THIS EVENING FOR PAZ012-018-019-026>028-041-042-045-046- 049>053. WIND CHILL WATCH FROM LATE MONDAY NIGHT THROUGH WEDNESDAY MORNING FOR PAZ012-018-019-025-026-034-035-037-041-042. WIND CHILL WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY MORNING FOR PAZ004>006-010-011-017-024-033. FREEZING RAIN ADVISORY FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING FOR PAZ056>059-063. FREEZING RAIN ADVISORY FROM 1 PM TO 4 PM EST THIS AFTERNOON FOR PAZ035. FREEZING RAIN ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST THIS EVENING FOR PAZ006-011-037. FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR PAZ064>066. FREEZING RAIN ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THIS AFTERNOON FOR PAZ036. && $$ SYNOPSIS...FITZGERALD NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD AVIATION...RXR
AREA FORECAST DISCUSSION
NWS STATE COLLEGE PA
621 AM EST SUN JAN 5 2014 .SYNOPSIS... LOW PRESSURE WILL TRACK WEST OF PENNSYLVANIA LATER TODAY. A TRAILING ARCTIC COLD FRONT WILL SWEEP THROUGH PENNSYLVANIA EARLY MONDAY. UPPER LOW AND ASSOCIATED ARCTIC AIR MASS WILL LIFT OUT OF THE AREA LATER NEXT WEEK. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... BASED ON UPSTREAM OBS AND LATEST MDL OUTPUT...HAVE DELAYED ARRIVAL OF RA/ZR ACROSS THE AREA TODAY. FZRA REPORTED AT KBWI AT 10Z AND LATEST RAP SUGGESTS -FZRA COULD ENTER YORK/LANCASTER COS AFTER 12Z. WAA UNDERWAY EARLY THIS MORNING WITH 8H TEMPS ALREADY RISING ABV 0C ACROSS SOUTHERN PA AT 10Z. MEANWHILE...SFC TEMPS IN THE SINGLE DIGITS ACROSS MANY PARTS OF CENTRAL PA...CREATING A CLASSIC FZRA SOUNDING PROFILE. EXPECT WARMER AIR TO EVENTUALLY WIN OUT BY EARLY EVENING ACROSS THE EASTERN COUNTIES...AS WEAK SFC LOW LIFTING UP THE COASTAL PLAIN TRACKS ACROSS EASTERN PA. PER WWD GRAPHICS...EXPECT FZRA ACCRETION TO BE LESS THAN A TENTH OF AN INCH...BUT ENOUGH TO CREATE POTENTIAL TRAVEL PROBLEMS. BY EARLY EVENING...STEADIEST RAIN ASSOC WITH WEAK SFC LOW SHOULD BE EXITING THE EASTERN COUNTIES. MEANWHILE...LIGHTER -DZ/-FZDZ COULD LINGER OVR THE CENTRAL MTNS AND SUSQ VALLEY...WHERE SREF AND NAM INDICATE A POCKET OF LINGERING SFC TEMPS NR 32F. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... BATCH OF PRECIP ASSOC WITH WEAK COASTAL LOW SHOULD BE EXITING EASTERN PA EARLY THIS EVENING. MEANWHILE...PRIMARY SURFACE LOW WILL TRACK WEST OF PA TONIGHT...KEEPING CENTRAL PA IN THE WARM SECTOR FOR MUCH OF THE NIGHT. ANY POCKETS OF SUB-FREEZING AIR SHOULD BE SCOURED OUT OF THE VALLEYS DURING THE EVENING...AS DEEP SOUTHERLY FLOW OVERSPREADS THE REGION IN ADVANCE OF APPROACHING ARCTIC COLD FRONT. ALL MDL GUIDANCE INDICATES ARCTIC COLD FRONT WILL SWEEP THRU CENTRAL PA BTWN 06Z-12Z. A BAND OF GUSTY RAIN SHOWERS ARE LIKELY TO ACCOMPANY FROPA ALONG AXIS OF ANOMALOUS SOUTHERLY LL JET/PWATS. ARRIVAL OF MUCH COLDER AIR WILL TURN THE SHRA TO SHSN OVR THE W MTNS WITH A LIGHT ACCUM OF AN INCH OR SO POSSIBLE. THE WET GROUND...COMBINED WITH RAPIDLY FALLING TEMPS BLW FREEZING...COULD POTENTIALLY PRODUCE BLACK ICE/FLASH FREEZE CONDITIONS EARLY MON AM. LATER SHIFTS MAY NEED TO CONSIDER POSSIBLE WINT WX ADV. STRONG CAA WILL CAUSE TEMPS TO BUCK THE TYPICAL DIURNAL TREND WITH FALLING TEMPS THRU THE DAY. BY EARLY MONDAY EVENING...GEFS ENS MEAN 8H TEMPS FALL TO -26C...CLOSE TO 3SD BLW NORMAL. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... AIR MASS AS DEFINED BY 8H TEMPS COULD BE THE COLDEST THIS REGION HAS SEEN IN 20 YEARS. BY TUES AM...THE CORE OF THE COLD SHOULD LIE ACROSS SOUTHWEST PA...WHERE GEFS ENS MEAN 8H TEMPS FALL TO -30C. THE FRIGID TEMPS...COMBINED WITH WGUSTS ARND 30KTS MON NIGHT THRU TUESDAY WILL RESULT IN EXTREMELY DANGEROUS CONDITIONS...MAKING FROSTBITE AND HYPOTHERMIA A REAL CONCERN EVEN IF EXPOSED TO THE ELEMENTS FOR ONLY A SHORT PERIOD. HAVE EXPANDED THE WIND CHILL WATCH EASTWARD INTO THE RIDGE/VALLEY REGION...AS CONFIDENCE INCREASES THAT WARNING CRITERIA OF 25 BLW WILL BE REACHED. ALTHOUGH IT APPEARS UNLIKELY WE WILL RIVAL THE MIN TEMPS OF 1994...WIND CHILLS MAY BE AS COLD OR COLDER AS TIGHT PRES GRADIENT CONTINUES TO BUFFET THE AREA WITH GUSTS NR 30KTS INTO TUE EVENING. SIG LAKE EFFECT DOES NOT APPEAR TO BE A CONCERN...AS MDL DATA INDICATES BLYR FLOW WILL KEEP SNOW SHOWERS NORTH OF THE BORDER MON-WED. WEDNESDAY MORNING WILL ALSO BE VERY COLD...AS WINDS SLACKEN UPON ARRIVAL OF SFC HIGH. MODEL CONSENSUS SUPPORTS TEMPS SLOWLY MODERATING BACK TOWARDS NORMAL BY THE SECOND HALF OF THE WEEK. A LIGHT OVERRUNNING SNOWFALL IS POSSIBLE LATE WEEK...AS WARMER SW FLOW TRIES TO DISLODGE LINGERING LOW LVL CHILL ACROSS THE NORTHEAST CONUS. && .AVIATION /12Z SUNDAY THROUGH THURSDAY/... VFR CONDITIONS WILL PREVAIL FOR MOST OF THE NIGHT INTO EARLY SUNDAY FOR MOST AREAS AS THE PRIMARY LOW PRESSURE SYSTEM APPROACHES FROM THE WEST. A WEAKER SECONDARY WAVE WILL LIFT UP THE COASTAL PLAIN TOMORROW. THIS SHOULD SPREAD MVFR CIGS INTO THE LOWER SUSQ VALLEY SITES OF KLNS-KMDT BY 10Z AT THE EARLIEST BUT BY 16Z AT THE LATEST. EXPECT SOUTHERLY FLOW TO INCREASE AS THE DAY WEARS ON...WITH LIGHT DRIZZLE/RAIN AND THEN LIGHT FZRA TO DEVELOP AND SPREAD THROUGHOUT THE SOUTHEAST. THIS RAIN AND THEN FREEZING RAIN WILL SLOWLY CREEP THROUGHOUT CENTRAL PA BY SUNDAY AFTERNOON AND EVENING. AS MENTIONED IT COULD START AS -DZ OR PERHAPS -FZDZ AND THEN SWITCH TO RAIN BETWEEN 21-03Z. THIS SHOULD LOWER VSBYS AND HAVE LOWER CIGS TO MVFR TO IFR. N AS WELL...POTENTIALLY LOWERING CIGS TO IFR THROUGH 06Z. ANOTHER ISSUE IS A STRONG LOW LEVEL JET THAT WILL BE PROPAGATING WITH THIS SYSTEM WITH WIND SHEAR AT 2KFT 170/40KTS POSSIBLE AT ALL TAF SITES BETWEEN 22Z TO 07Z MONDAY. OUTLOOK... SUN...CLOUDS THICKEN AND LOWER...INITIALLY IN THE EAST BUT AREA WIDE IN THE AFTERNOON. RAIN OR MIXED PRECIP BECOMING LIKELY. MON...RESTRICTIONS IN THE MORNING...THEN IMPROVING CIGS /ESP SE HALF/ AS STRONG WESTERLY WINDS DEVELOP. TUE...SCT SNOW SHOWERS NW. VFR ELSEWHERE. WINDY. WED...SCT SNOW SHOWERS NW. VFR ELSEWHERE. THU...MVFR TO IFR WITH CHC LIGHT SNOW. && .CTP WATCHES/WARNINGS/ADVISORIES... FREEZING RAIN ADVISORY FROM 1 PM THIS AFTERNOON TO 7 PM EST THIS EVENING FOR PAZ012-018-019-026>028-041-042-045-046- 049>053. WIND CHILL WATCH FROM LATE MONDAY NIGHT THROUGH WEDNESDAY MORNING FOR PAZ012-018-019-025-026-034-035-037-041-042. WIND CHILL WATCH FROM MONDAY AFTERNOON THROUGH WEDNESDAY MORNING FOR PAZ004>006-010-011-017-024-033. FREEZING RAIN ADVISORY FROM 10 AM THIS MORNING TO 7 PM EST THIS EVENING FOR PAZ056>059-063. FREEZING RAIN ADVISORY FROM 1 PM TO 4 PM EST THIS AFTERNOON FOR PAZ035. FREEZING RAIN ADVISORY FROM 4 PM THIS AFTERNOON TO 7 PM EST THIS EVENING FOR PAZ006-011-037. FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR PAZ064>066. FREEZING RAIN ADVISORY FROM 10 AM THIS MORNING TO 4 PM EST THIS AFTERNOON FOR PAZ036. && $$ SYNOPSIS...FITZGERALD NEAR TERM...FITZGERALD SHORT TERM...FITZGERALD LONG TERM...FITZGERALD AVIATION...DEVOIR/CERU
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
1002 AM EST SUN JAN 5 2014 .SYNOPSIS... A VERY STRONG AND DEEP UPPER LEVEL TROUGH WILL SWING AN ARCTIC COLD FRONT OVER THE REGION EARLY MONDAY AND USHER IN RECORD LEVEL COLD TEMPERATURES FOR MONDAY NIGHT AND TUESDAY. THIS AIRMASS WILL SLOWLY WARM BACK TO NORMAL LEVELS BY THE END OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... 1000 AM UPDATE...FREEZING RAIN ADVISORY ALLOWED TO EXPIRE AS TEMPS...AS WELL AS WET BULB TEMPS...ARE ABOVE FREEZING. SOME LIGHT RAIN MAY FALL IN THE OLD ADVISORY AREA THRU MIDDAY. 915 AM UPDATE...A FEW PATCHES OF RAINFALL ARE SEEN ON RADAR AT THIS HOUR OVER THE PIEDMONT AND NC FOOTHILLS. MOIST UPGLIDE CONTINUES TO DRIVE THE PRECIP THOUGH CONVECTION IS PLAYING A SMALL ROLE AND PROVIDING LOCALIZED ENHANCEMENT. PROG SOUNDINGS DO SUGGEST LESS THAN 100 J OF CAPE ABOVE INVERSION. THUNDER STILL A LONG SHOT WITH PARCELS STRUGGLING TO REACH EVEN THE FREEZING LEVEL...BUT DID INCLUDE SOME SUB-SCHC THUNDER CHANCES TODAY IN REVISED POPS...WHICH ARE GENERALLY A BIT HIGHER THAN BEFORE. CONVECTION ALLOWING MODELS STILL FAVOR THE ERN PIEDMONT...BUT DO FEATURE SOME SPRINKLES FURTHER WEST. RAP AND 12Z NAM ARE MORE WIDESPREAD...INDICATING POPS ACRS THE AREA OF UPGLIDE UNTIL TRENDING DOWN IN THE WEST THIS AFTN AS FLOW TURNS MORE SWLY AND LESS WARM ADVECTIVE. I MAINTAINED A LULL IN THE CENTRAL PORTION OF THE CWFA BETWEEN THE DIMINISHING UPGLIDE AND STRENGTHENING FLOW AHEAD OF SYNOPTIC FORCING/FROPA TONIGHT. TEMPS WERE TOO WARM PER NEWEST GUIDANCE...INCLUDING HOURLY SHORT TERM MODELS...WHICH REFLECT THE PERSISTENT LOW STRATUS AND FOG TODAY. HIGHS WERE GENERALLY LOWERED 3-5 DEGREES. AS OF 300 AM...CURRENTLY UPGLIDE SHWRS/DRIZZLE CONTINUE TO EXPAND IN COVERAGE ACRS SC AND THE NC PIEDMONT. MEANWHILE...NUMEROUS TEMP SENSORS ARE HOVERING IN THE 30-32 DEG RANGE ACRS MUCH OF THE NC FOOTHILLS AND NW PIEDMONT. GIVEN THE STRONGER RADAR RETURNS HEADING TOWARD THE NC PIEDMONT...I PLAN TO EXPAND THE FREEZING RAIN ADVISORY TO INCLUDE THE REST OF THE NC FOOTHILLS....AND ALL THE NW PIEDMONT. I WILL HAVE IT GO TILL 15Z...THO TEMPS SHUD START WARMING ABV FREEZING BEFORE THEN. FOR TODAY...THE BAND OF MOIST UPGLIDE PRECIP SHUD SHIFT EAST OF THE AREA BY LATE MORNING...WHILE THE NEXT BAND OF PRECIP ASSOCIATED WITH APPROACHING ARCTIC COLD FRONT WILL STILL BE TO THE WEST. SO EXPECT A LULL IN -RA/DZ FOR THE AFTN. HOWEVER...CLOUDS SHUD PERSIST...SAVE FOR SOME OF THE BREAKS POSSIBLE IN SOME OF THE NC MTN VLYS DUE TO STRONG SWLY DOWNSLOPE FLOW. TEMPS APPEAR TRICKY...AS COLD POOL WILL LINGER EAST OF THE MTNS...BUT LACK OF PRECIP SHUD ALLOW SOME WARMING AIDED BY STRONG WAA. FOR NOW...FORECASTING TEMPS TO RISE INTO THE 40S AS THE DAY WEARS ON. TONIGHT...GUIDANCE HAS SLOWED DOWN TIMING OF STRONG ARCTIC FROPA SLIGHTLY...BRINGING IT THRU THE CWFA BETWEEN MIDNIGHT AND 6 AM MONDAY. A SWLY 50-60 KT LLJ WILL TRANSVERSE THE CWFA JUST AHEAD OF THE FRONT. SO A BRIEF PERIOD OF STRONG WIND GUSTS WILL BE POSSIBLE ALONG SOME OF THE RIDGES. HOWEVER...SHUD BE CONFINED IN AREA AND TOO BRIEF TO WARRANT ANY HEADLINE FOR IT ATTM. OTHERWISE...POPS RAMP UP TO LIKELY TO CATEGORICAL FOR A FEW HOURS OVERNIGHT. QPF LOOKS LIGHT...GENERALLY UNDER 0.25" FOR MOST AREAS...EXCEPT 0.25-0.5" ABOVE 3500 FT IN THE MTNS. SNOW LEVELS SHUD START TO FALL AROUND MIDNIGHT TO VALLEY FLOORS BY 6 AM. EVEN SOME CHANGEOVER MAY OCCUR IN THE NC FOOTHILLS BEFORE PRECIP TAPERS OFF. GIVEN A SLIGHTLY SLOWER TIMING OF THE CAA...SNOW ACCUMS LOOK TO BE CONFINED MOSTLY TO ABOVE 3500 FT UNTIL CLOSE TO DAYBREAK...WHEN IT WILL START ACCUMULATING IN THE VALLEYS. TEMPS ARE EXPECTED TO ALREADY BE IN THE TEENS TO MID 20S BY DAYBREAK IN THE MTNS. MEANWHILE...TEMPS WILL CONT TO RISE OR HOLD STEADY WITH STRONG WAA AHEAD OF THE FRONT ACRS THE SOUTHEAST CORNER OF THE CWFA...INCLUDING CHARLOTTE...WHERE SOME 50S MAY OCCUR BEFORE FROPA. THERE DOESN/T LOOK TO BE ENUF INSTBY OR FORCING FOR THUNDER. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... AS OF 330 AM SUNDAY...NOT MUCH CHANGE FROM EARLIER THINKING WITH REGARD TO THE IMPACTS ACROSS THE WESTERN CAROLINAS FROM THE PASSAGE OF AN ARCTIC COLD FRONT MONDAY MORNING...SO IT IS TIME TO ACT. STILL EXPECTING THE FRONT TO BE PUSHING EAST ACROSS THE PIEDMONT AT SUNRISE MONDAY. PRECIPITATION SHOULD HAVE ALREADY CHANGED TO SNOW ACROSS THE MTNS. E OF THE MTNS...LINGERING PRECIP COULD CHANGE OVER TO A BRIEF PERIOD OF SNOW SHOWERS OR FLURRIES BEFORE ENDING MID MORNING...AS COLD AIR MOVES IN BEHIND FRONT...BUT NO SIGNIFICANT ACCUM IS EXPECTED. TEMPS MAY FALL BRIEFLY...THEN STABILIZE OR RISE A FEW DEGREES DURING LATE MORNING...BUT THEN STRONG COLD ADVECTION WILL TAKE OVER AND TEMPS WILL FALL THROUGH THE AFTERNOON. SNOW PRODUCTION WILL CONTINUE NEAR THE TN BORDER THROUGHOUT MONDAY AS TEMPS FALL AND MOISTURE IS PUSHED UP THE W SIDE OF THE MTNS. THERE ARE SOME MIXED SIGNALS AS TO WHAT THE POTENTIAL FOR ACCUMULATION WILL BE. ON THE ONE HAND...THE MODELS FCST WEAK SFC BASED CAPE UPSTREAM...BUT THE SURFACE MIGHT BE FREEZING BY MONDAY AFTERNOON UPSTREAM...WHICH MIGHT CUT BACK ON MOISTURE FLUX FROM THE GROUND. THERE SHOULD BE SOME MID LEVEL FORCING IN THE AFTERNOON AS DPVA MOVES OVERHEAD...BUT THE 850MB WIND RETAINS A MORE WESTERLY COMPONENT...WHICH ALSO DOES NOT ALLOW FOR A GREAT LAKES CONNECTION. THESE MIGHT PROVE TO BE LIMITING FACTORS...SO THE POTENTIAL LOOKS TO BE SOMEWHERE IN THE NEIGHBORHOOD OF 3-5 INCHES ON MTN PEAKS AND 2 INCHES IN THE VALLEYS. GIVEN THAT NEIGHBORING OFFICES ARE GOING WITH A WARNING...THE BEST COURSE OF ACTION WILL BE TO ALSO GO WITH A WINTER STORM WARNING FOR THE COUNTIES ALONG THE TN BORDER STARTING AT MIDNIGHT AND RUNNING THROUGH 6 PM MONDAY. NOTE THAT ONLY THE RIDGETOPS ARE LIKELY TO REACH WARNING CRITERIA ACCUMULATION...WHILE THE VALLEYS WILL GET LESS SNOW...BUT THAT PERHAPS THE IMPACT OF BLOWING SNOW AND VERY COLD TEMPS MIGHT MAKE IT DANGEROUS ENOUGH THAT PUBLIC IMPACT JUSTIFIES THE WARNING. THE ARCTIC AIR REALLY TAKES HOLD MONDAY NIGHT AND TUESDAY. TEMPS WILL BE WELL BELOW NORMAL...LIKELY MORE THAN 20 DEGREES BELOW NORMAL. THE GUIDANCE CONTINUES TO TREND COOLER WITH EACH RUN...SO THE FCST LOWS ARE NOW SOLIDLY IN RECORD TERRITORY. WIND GUST POTENTIAL MAY PEAK MONDAY EVENING AS THE SHORT WAVE PASSES THROUGH. WIND CHILL VALUES WILL FALL THROUGH THE ADVISORY RANGE MONDAY AFTERNOON ACROSS THE MTNS...AND BELOW WARNING CRITERIA AROUND SUNSET MONDAY. FOR THAT REASON...A WIND CHILL WATCH WILL BE ISSUED FOR THE MTNS AND HIGH ELEVATION FOOTHILL ZONES FOR MONDAY NIGHT THROUGH NOON TUESDAY. VALUES MAY REACH ADVISORY CRITERIA OUTSIDE THE MTNS...SO AN ADVISORY MAY BE ISSUED LATER TODAY. ON TUESDAY...HIGH TEMPS WILL REMAIN IN THE TEENS TO LOWER 20S OVER THE MTNS. TEMPS WILL PROBABLY STAY BELOW FREEZING OUTSIDE OF THE MTNS...WHICH WOULD BE REMARKABLE WITH NO SNOW ON THE GROUND. GUIDANCE TEMPS WERE SLIGHTLY COOLER THAN THE PREV FCST ONCE AGAIN...AND THIS TREND WAS FOLLOWED. THE REST OF THE SHORT RANGE REMAINS QUIET. THE ARCTIC HIGH REMAINS IN CONTROL THROUGH WEDNESDAY...WITH THE AIR MASS SLOWLY MODIFYING. TEMPS WILL REMAIN RATHER COLD...ONLY NOT TO THE EXTREME WE WILL SEE MONDAY NIGHT AND TUESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... AS OF 300 AM EST SUNDAY...THE LATEST 00Z GFS/ECMWF AGREE THAT SWLY FLOW ALOFT WILL PERSIST ACROSS THE REGION WED NIGHT INTO THU...WITH A WEAK SOUTHERN STREAM UPPER SHORTWAVE PASSING OVERHEAD THU NIGHT INTO EARLY FRI. THE ECMWF DEVELOPS UPPER RIDGING ACROSS THE REGION FRI THRU EARLY SUN AS ANOTHER SOUTHERN STREAM UPPER SHORTWAVE TROUGH EJECTS OUT OF THE DESERT SW AND REACHES WESTERN GULF. MEANWHILE...THE FASTER GFS PUSHES THIS THROUGH INTO THE MISSISSIPPI VALLEY BY SAT NIGHT AND MAINTAINS SWLY FLOW ALOFT ACROSS THE REGION. AT THE SURFACE...MOIST RETURN FLOW WILL DEVELOP ACROSS THE REGION BY WED NIGHT AS HIGH PRESSURE SLIDES OFF THE MID ATLANTIC COAST. WITH INCREASING ISENTROPIC LIFT AND A PASSAGE OF UPPER SHORTWAVE ON THU...LIGHT PRECIP WILL DEVELOP ACROSS THE REGION BY EARLY THU AFTERNOON. PRECIP WILL BE MAINLY LIQUID THOUGH A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE AT THE ONSET OF PRECIP. THE ECMWF THEN DEVELOPS BROAD AREAS OF DRY HIGH PRESSURE ACROSS THE SE THU NIGHT INTO SAT...WHILE THE GFS KEEPS THE HIGH OFF THE ATLANTIC COAST AND SLOWLY PUSHES A COLD FRONT INTO THE TN VALLEY BY FRI NIGHT MAINTAINING DEEP SOUTHERLY FLOW ACROSS THE REGION. THE GFS SLOWLY PUSHES THE FRONT THROUGH THE REGION SAT NIGHT INTO SUN WITH A SERIES OF SURFACE WAVES RIDING ALONG THE FRONT. USING A COMPROMISE BETWEEN THE DRY ECMWF AND THE WET GFS...HAVE INHERITED SLIGHT CHANCE POPS ON FRI AND LOWERED POPS FROM THE HIGH END CHANCE/LIKELY TO THE 30/40 PERCENT RANGE ON SAT. THANKS TO WELL ABOVE FREEZING TEMPS...PRECIP WILL BE ALL LIQUID. TEMPS WILL START OUT AROUND 10-15 DEGREES BELOW NORMAL ON THU AND QUICKLY WARM BACK UP TO NEAR NORMAL BY FRI. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... AT KCLT /15Z UPDATE/...PERSISTENT MOIST LLVL UPGLIDE WILL KEEP LIFR/IFR CIGS THRU THE DAY. PATCHY -SHRA AND DZ WILL BE AROUND AT LEAST THRU THE MORNING. IFR VSBY LIKELY THRU MIDDAY WITH SHOWERS ONLY REINFORCING SFC SATURATION. GUIDANCE AGREES ON LITTLE IMPROVEMENT IN CIGS DURING THE AFTN...THEN POSSIBLY LOWERING IN THE 200-300 FT RANGE THIS EVENING WITH DECREASING VSBY. THERE WILL ALSO BE A STRONG LLJ OF 40-50 KTS ATOP A STRONG INVERSION ABOUT 2000 FT AGL. SO HAVE ADDED LLWS STARTING AROUND 5Z UNTIL THE COLD FRONT PASSES THRU BEFORE DAYBREAK MONDAY. RAIN LOOKS TO BE LIGHT WITH THE COLD FRONT...BUT WILL INCLUDE PREVAILING -SHRA. ELSEWHERE...ALL SITES LOOK TO BE IFR OR LIFR THRU MOST OF THE PERIOD...UNTIL A STRONG COLD FRONT PUSHES THRU FROM WEST TO EAST OVERNIGHT TONIGHT. THE MAIN EXCEPTION IS KAVL...WHERE GUIDANCE HINTS THAT STRONG SWLY DOWNSLOPE WINDS MAY HELP SCOUR OUT SOME OF THE LOW CLOUDS. WILL GO WITH MVFR FOR THIS AFTN THERE...BUT IT MAY EVEN GO VFR BRIEFLY. BUT OTHERWISE...LOW STRATUS AND PATCHY -SHRA AND DZ THRU THE DAY...WITH MOST PRECIP THIS MORNING...THEN AGAIN TONIGHT WITH FRONT. THE TOUGHEST PART OF THE FCST IS VSBY...WITH METARS CONTINUING TO DROP...AND POTENTIAL FOR A LOT MORE FOG AROUND TODAY AND THIS EVENING. DENSE FOG LOOKS MOST LIKELY IF IT OCCURS TO BE NEAR THE BLUE RIDGE AND ADJACENT FOOTHILLS...ESP THIS EVENING. THE OTHER ISSUE TONIGHT WILL BE 40-50 KT JET ATOP A STRONG INVERSION. HAVE ADDED MENTION OF LLWS. OUTLOOK...CONDITIONS SHOULD IMPROVE QUICKLY TO VFR BY MIDDAY MONDAY...BUT NORTHWEST FLOW SNOW WILL RETURN TO THE MTNS WITH GUSTY NW WINDS DEVELOPING ACRS THE REGION. VERY COLD AND DRY HIGH PRES SETTLES IN FOR TUESDAY AND WEDNESDAY... WITH WINTRY PRECIP POSSIBLY RETURNING WITH ANOTHER FRONT ON THURSDAY. CONFIDENCE TABLE... 15-21Z 21-03Z 03-09Z 09-15Z KCLT MED 66% MED 77% HIGH 91% MED 70% KGSP MED 70% HIGH 82% HIGH 89% MED 63% KAVL MED 75% HIGH 84% MED 74% HIGH 83% KHKY MED 61% HIGH 83% HIGH 85% MED 63% KGMU MED 70% HIGH 80% HIGH 85% MED 63% KAND MED 66% HIGH 86% HIGH 83% MED 63% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOW MINIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL... 3 IN 1879 CLT...12 IN 1884 GSP... 9 IN 1904 RECORD LOW MAXIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL...21 IN 1988 CLT...24 IN 1988 GSP...27 IN 1988 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR NCZ033-048>053-058-059-062>065-501-503-505-507-509. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM EST MONDAY FOR NCZ033-048>052-058. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...ARK/WIMBERLEY SHORT TERM...PM LONG TERM...JOH AVIATION...ARK/WIMBERLEY CLIMATE...
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
939 AM EST SUN JAN 5 2014 .SYNOPSIS... A VERY STRONG AND DEEP UPPER LEVEL TROUGH WILL SWING AN ARCTIC COLD FRONT OVER THE REGION EARLY MONDAY AND USHER IN RECORD LEVEL COLD TEMPERATURES FOR MONDAY NIGHT AND TUESDAY. THIS AIRMASS WILL SLOWLY WARM BACK TO NORMAL LEVELS BY THE END OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... 915 AM UPDATE...A FEW PATCHES OF RAINFALL ARE SEEN ON RADAR AT THIS HOUR OVER THE PIEDMONT AND NC FOOTHILLS. MOIST UPGLIDE CONTINUES TO DRIVE THE PRECIP THOUGH CONVECTION IS PLAYING A SMALL ROLE AND PROVIDING LOCALIZED ENHANCEMENT. PROG SOUNDINGS DO SUGGEST LESS THAN 100 J OF CAPE ABOVE INVERSION. THUNDER STILL A LONG SHOT WITH PARCELS STRUGGLING TO REACH EVEN THE FREEZING LEVEL...BUT DID INCLUDE SOME SUB-SCHC THUNDER CHANCES TODAY IN REVISED POPS...WHICH ARE GENERALLY A BIT HIGHER THAN BEFORE. CONVECTION ALLOWING MODELS STILL FAVOR THE ERN PIEDMONT...BUT DO FEATURE SOME SPRINKLES FURTHER WEST. RAP AND 12Z NAM ARE MORE WIDESPREAD...INDICATING POPS ACRS THE AREA OF UPGLIDE UNTIL TRENDING DOWN IN THE WEST THIS AFTN AS FLOW TURNS MORE SWLY AND LESS WARM ADVECTIVE. I MAINTAINED A LULL IN THE CENTRAL PORTION OF THE CWFA BETWEEN THE DIMINISHING UPGLIDE AND STRENGTHENING FLOW AHEAD OF SYNOPTIC FORCING/FROPA TONIGHT. TEMPS WERE TOO WARM PER NEWEST GUIDANCE...INCLUDING HOURLY SHORT TERM MODELS...WHICH REFLECT THE PERSISTENT LOW STRATUS AND FOG TODAY. HIGHS WERE GENERALLY LOWERED 3-5 DEGREES. AS OF 300 AM...CURRENTLY UPGLIDE SHWRS/DRIZZLE CONTINUE TO EXPAND IN COVERAGE ACRS SC AND THE NC PIEDMONT. MEANWHILE...NUMEROUS TEMP SENSORS ARE HOVERING IN THE 30-32 DEG RANGE ACRS MUCH OF THE NC FOOTHILLS AND NW PIEDMONT. GIVEN THE STRONGER RADAR RETURNS HEADING TOWARD THE NC PIEDMONT...I PLAN TO EXPAND THE FREEZING RAIN ADVISORY TO INCLUDE THE REST OF THE NC FOOTHILLS....AND ALL THE NW PIEDMONT. I WILL HAVE IT GO TILL 15Z...THO TEMPS SHUD START WARMING ABV FREEZING BEFORE THEN. FOR TODAY...THE BAND OF MOIST UPGLIDE PRECIP SHUD SHIFT EAST OF THE AREA BY LATE MORNING...WHILE THE NEXT BAND OF PRECIP ASSOCIATED WITH APPROACHING ARCTIC COLD FRONT WILL STILL BE TO THE WEST. SO EXPECT A LULL IN -RA/DZ FOR THE AFTN. HOWEVER...CLOUDS SHUD PERSIST...SAVE FOR SOME OF THE BREAKS POSSIBLE IN SOME OF THE NC MTN VLYS DUE TO STRONG SWLY DOWNSLOPE FLOW. TEMPS APPEAR TRICKY...AS COLD POOL WILL LINGER EAST OF THE MTNS...BUT LACK OF PRECIP SHUD ALLOW SOME WARMING AIDED BY STRONG WAA. FOR NOW...FORECASTING TEMPS TO RISE INTO THE 40S AS THE DAY WEARS ON. TONIGHT...GUIDANCE HAS SLOWED DOWN TIMING OF STRONG ARCTIC FROPA SLIGHTLY...BRINGING IT THRU THE CWFA BETWEEN MIDNIGHT AND 6 AM MONDAY. A SWLY 50-60 KT LLJ WILL TRANSVERSE THE CWFA JUST AHEAD OF THE FRONT. SO A BRIEF PERIOD OF STRONG WIND GUSTS WILL BE POSSIBLE ALONG SOME OF THE RIDGES. HOWEVER...SHUD BE CONFINED IN AREA AND TOO BRIEF TO WARRANT ANY HEADLINE FOR IT ATTM. OTHERWISE...POPS RAMP UP TO LIKELY TO CATEGORICAL FOR A FEW HOURS OVERNIGHT. QPF LOOKS LIGHT...GENERALLY UNDER 0.25" FOR MOST AREAS...EXCEPT 0.25-0.5" ABOVE 3500 FT IN THE MTNS. SNOW LEVELS SHUD START TO FALL AROUND MIDNIGHT TO VALLEY FLOORS BY 6 AM. EVEN SOME CHANGEOVER MAY OCCUR IN THE NC FOOTHILLS BEFORE PRECIP TAPERS OFF. GIVEN A SLIGHTLY SLOWER TIMING OF THE CAA...SNOW ACCUMS LOOK TO BE CONFINED MOSTLY TO ABOVE 3500 FT UNTIL CLOSE TO DAYBREAK...WHEN IT WILL START ACCUMULATING IN THE VALLEYS. TEMPS ARE EXPECTED TO ALREADY BE IN THE TEENS TO MID 20S BY DAYBREAK IN THE MTNS. MEANWHILE...TEMPS WILL CONT TO RISE OR HOLD STEADY WITH STRONG WAA AHEAD OF THE FRONT ACRS THE SOUTHEAST CORNER OF THE CWFA...INCLUDING CHARLOTTE...WHERE SOME 50S MAY OCCUR BEFORE FROPA. THERE DOESN/T LOOK TO BE ENUF INSTBY OR FORCING FOR THUNDER. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... AS OF 330 AM SUNDAY...NOT MUCH CHANGE FROM EARLIER THINKING WITH REGARD TO THE IMPACTS ACROSS THE WESTERN CAROLINAS FROM THE PASSAGE OF AN ARCTIC COLD FRONT MONDAY MORNING...SO IT IS TIME TO ACT. STILL EXPECTING THE FRONT TO BE PUSHING EAST ACROSS THE PIEDMONT AT SUNRISE MONDAY. PRECIPITATION SHOULD HAVE ALREADY CHANGED TO SNOW ACROSS THE MTNS. E OF THE MTNS...LINGERING PRECIP COULD CHANGE OVER TO A BRIEF PERIOD OF SNOW SHOWERS OR FLURRIES BEFORE ENDING MID MORNING...AS COLD AIR MOVES IN BEHIND FRONT...BUT NO SIGNIFICANT ACCUM IS EXPECTED. TEMPS MAY FALL BRIEFLY...THEN STABILIZE OR RISE A FEW DEGREES DURING LATE MORNING...BUT THEN STRONG COLD ADVECTION WILL TAKE OVER AND TEMPS WILL FALL THROUGH THE AFTERNOON. SNOW PRODUCTION WILL CONTINUE NEAR THE TN BORDER THROUGHOUT MONDAY AS TEMPS FALL AND MOISTURE IS PUSHED UP THE W SIDE OF THE MTNS. THERE ARE SOME MIXED SIGNALS AS TO WHAT THE POTENTIAL FOR ACCUMULATION WILL BE. ON THE ONE HAND...THE MODELS FCST WEAK SFC BASED CAPE UPSTREAM...BUT THE SURFACE MIGHT BE FREEZING BY MONDAY AFTERNOON UPSTREAM...WHICH MIGHT CUT BACK ON MOISTURE FLUX FROM THE GROUND. THERE SHOULD BE SOME MID LEVEL FORCING IN THE AFTERNOON AS DPVA MOVES OVERHEAD...BUT THE 850MB WIND RETAINS A MORE WESTERLY COMPONENT...WHICH ALSO DOES NOT ALLOW FOR A GREAT LAKES CONNECTION. THESE MIGHT PROVE TO BE LIMITING FACTORS...SO THE POTENTIAL LOOKS TO BE SOMEWHERE IN THE NEIGHBORHOOD OF 3-5 INCHES ON MTN PEAKS AND 2 INCHES IN THE VALLEYS. GIVEN THAT NEIGHBORING OFFICES ARE GOING WITH A WARNING...THE BEST COURSE OF ACTION WILL BE TO ALSO GO WITH A WINTER STORM WARNING FOR THE COUNTIES ALONG THE TN BORDER STARTING AT MIDNIGHT AND RUNNING THROUGH 6 PM MONDAY. NOTE THAT ONLY THE RIDGETOPS ARE LIKELY TO REACH WARNING CRITERIA ACCUMULATION...WHILE THE VALLEYS WILL GET LESS SNOW...BUT THAT PERHAPS THE IMPACT OF BLOWING SNOW AND VERY COLD TEMPS MIGHT MAKE IT DANGEROUS ENOUGH THAT PUBLIC IMPACT JUSTIFIES THE WARNING. THE ARCTIC AIR REALLY TAKES HOLD MONDAY NIGHT AND TUESDAY. TEMPS WILL BE WELL BELOW NORMAL...LIKELY MORE THAN 20 DEGREES BELOW NORMAL. THE GUIDANCE CONTINUES TO TREND COOLER WITH EACH RUN...SO THE FCST LOWS ARE NOW SOLIDLY IN RECORD TERRITORY. WIND GUST POTENTIAL MAY PEAK MONDAY EVENING AS THE SHORT WAVE PASSES THROUGH. WIND CHILL VALUES WILL FALL THROUGH THE ADVISORY RANGE MONDAY AFTERNOON ACROSS THE MTNS...AND BELOW WARNING CRITERIA AROUND SUNSET MONDAY. FOR THAT REASON...A WIND CHILL WATCH WILL BE ISSUED FOR THE MTNS AND HIGH ELEVATION FOOTHILL ZONES FOR MONDAY NIGHT THROUGH NOON TUESDAY. VALUES MAY REACH ADVISORY CRITERIA OUTSIDE THE MTNS...SO AN ADVISORY MAY BE ISSUED LATER TODAY. ON TUESDAY...HIGH TEMPS WILL REMAIN IN THE TEENS TO LOWER 20S OVER THE MTNS. TEMPS WILL PROBABLY STAY BELOW FREEZING OUTSIDE OF THE MTNS...WHICH WOULD BE REMARKABLE WITH NO SNOW ON THE GROUND. GUIDANCE TEMPS WERE SLIGHTLY COOLER THAN THE PREV FCST ONCE AGAIN...AND THIS TREND WAS FOLLOWED. THE REST OF THE SHORT RANGE REMAINS QUIET. THE ARCTIC HIGH REMAINS IN CONTROL THROUGH WEDNESDAY...WITH THE AIR MASS SLOWLY MODIFYING. TEMPS WILL REMAIN RATHER COLD...ONLY NOT TO THE EXTREME WE WILL SEE MONDAY NIGHT AND TUESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/... AS OF 300 AM EST SUNDAY...THE LATEST 00Z GFS/ECMWF AGREE THAT SWLY FLOW ALOFT WILL PERSIST ACROSS THE REGION WED NIGHT INTO THU...WITH A WEAK SOUTHERN STREAM UPPER SHORTWAVE PASSING OVERHEAD THU NIGHT INTO EARLY FRI. THE ECMWF DEVELOPS UPPER RIDGING ACROSS THE REGION FRI THRU EARLY SUN AS ANOTHER SOUTHERN STREAM UPPER SHORTWAVE TROUGH EJECTS OUT OF THE DESERT SW AND REACHES WESTERN GULF. MEANWHILE...THE FASTER GFS PUSHES THIS THROUGH INTO THE MISSISSIPPI VALLEY BY SAT NIGHT AND MAINTAINS SWLY FLOW ALOFT ACROSS THE REGION. AT THE SURFACE...MOIST RETURN FLOW WILL DEVELOP ACROSS THE REGION BY WED NIGHT AS HIGH PRESSURE SLIDES OFF THE MID ATLANTIC COAST. WITH INCREASING ISENTROPIC LIFT AND A PASSAGE OF UPPER SHORTWAVE ON THU...LIGHT PRECIP WILL DEVELOP ACROSS THE REGION BY EARLY THU AFTERNOON. PRECIP WILL BE MAINLY LIQUID THOUGH A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE AT THE ONSET OF PRECIP. THE ECMWF THEN DEVELOPS BROAD AREAS OF DRY HIGH PRESSURE ACROSS THE SE THU NIGHT INTO SAT...WHILE THE GFS KEEPS THE HIGH OFF THE ATLANTIC COAST AND SLOWLY PUSHES A COLD FRONT INTO THE TN VALLEY BY FRI NIGHT MAINTAINING DEEP SOUTHERLY FLOW ACROSS THE REGION. THE GFS SLOWLY PUSHES THE FRONT THROUGH THE REGION SAT NIGHT INTO SUN WITH A SERIES OF SURFACE WAVES RIDING ALONG THE FRONT. USING A COMPROMISE BETWEEN THE DRY ECMWF AND THE WET GFS...HAVE INHERITED SLIGHT CHANCE POPS ON FRI AND LOWERED POPS FROM THE HIGH END CHANCE/LIKELY TO THE 30/40 PERCENT RANGE ON SAT. THANKS TO WELL ABOVE FREEZING TEMPS...PRECIP WILL BE ALL LIQUID. TEMPS WILL START OUT AROUND 10-15 DEGREES BELOW NORMAL ON THU AND QUICKLY WARM BACK UP TO NEAR NORMAL BY FRI. && .AVIATION /15Z SUNDAY THROUGH THURSDAY/... AT KCLT /15Z UPDATE/...PERSISTENT MOIST LLVL UPGLIDE WILL KEEP LIFR/IFR CIGS THRU THE DAY. PATCHY -SHRA AND DZ WILL BE AROUND AT LEAST THRU THE MORNING. IFR VSBY LIKELY THRU MIDDAY WITH SHOWERS ONLY REINFORCING SFC SATURATION. GUIDANCE AGREES ON LITTLE IMPROVEMENT IN CIGS DURING THE AFTN...THEN POSSIBLY LOWERING IN THE 200-300 FT RANGE THIS EVENING WITH DECREASING VSBY. THERE WILL ALSO BE A STRONG LLJ OF 40-50 KTS ATOP A STRONG INVERSION ABOUT 2000 FT AGL. SO HAVE ADDED LLWS STARTING AROUND 5Z UNTIL THE COLD FRONT PASSES THRU BEFORE DAYBREAK MONDAY. RAIN LOOKS TO BE LIGHT WITH THE COLD FRONT...BUT WILL INCLUDE PREVAILING -SHRA. ELSEWHERE...ALL SITES LOOK TO BE IFR OR LIFR THRU MOST OF THE PERIOD...UNTIL A STRONG COLD FRONT PUSHES THRU FROM WEST TO EAST OVERNIGHT TONIGHT. THE MAIN EXCEPTION IS KAVL...WHERE GUIDANCE HINTS THAT STRONG SWLY DOWNSLOPE WINDS MAY HELP SCOUR OUT SOME OF THE LOW CLOUDS. WILL GO WITH MVFR FOR THIS AFTN THERE...BUT IT MAY EVEN GO VFR BRIEFLY. BUT OTHERWISE...LOW STRATUS AND PATCHY -SHRA AND DZ THRU THE DAY...WITH MOST PRECIP THIS MORNING...THEN AGAIN TONIGHT WITH FRONT. THE TOUGHEST PART OF THE FCST IS VSBY...WITH METARS CONTINUING TO DROP...AND POTENTIAL FOR A LOT MORE FOG AROUND TODAY AND THIS EVENING. DENSE FOG LOOKS MOST LIKELY IF IT OCCURS TO BE NEAR THE BLUE RIDGE AND ADJACENT FOOTHILLS...ESP THIS EVENING. THE OTHER ISSUE TONIGHT WILL BE 40-50 KT JET ATOP A STRONG INVERSION. HAVE ADDED MENTION OF LLWS. OUTLOOK...CONDITIONS SHOULD IMPROVE QUICKLY TO VFR BY MIDDAY MONDAY...BUT NORTHWEST FLOW SNOW WILL RETURN TO THE MTNS WITH GUSTY NW WINDS DEVELOPING ACRS THE REGION. VERY COLD AND DRY HIGH PRES SETTLES IN FOR TUESDAY AND WEDNESDAY... WITH WINTRY PRECIP POSSIBLY RETURNING WITH ANOTHER FRONT ON THURSDAY. CONFIDENCE TABLE... 14-20Z 20-02Z 02-08Z 08-14Z KCLT MED 78% MED 79% HIGH 95% HIGH 83% KGSP MED 72% HIGH 93% HIGH 97% MED 70% KAVL HIGH 80% HIGH 86% HIGH 82% MED 68% KHKY MED 75% HIGH 92% HIGH 95% MED 66% KGMU MED 73% HIGH 90% HIGH 95% MED 70% KAND MED 75% HIGH 85% HIGH 84% MED 70% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOW MINIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL... 3 IN 1879 CLT...12 IN 1884 GSP... 9 IN 1904 RECORD LOW MAXIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL...21 IN 1988 CLT...24 IN 1988 GSP...27 IN 1988 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM EST MONDAY FOR NCZ033-048>052-058. WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR NCZ033-048>053-058-059-062>065-501-503-505-507-509. FREEZING RAIN ADVISORY UNTIL 10 AM EST THIS MORNING FOR NCZ035>037-056-057-068-069-501>510. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...ARK/WIMBERLEY SHORT TERM...PM LONG TERM...JOH AVIATION...ARK/WIMBERLEY CLIMATE...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1244 PM EST SUN JAN 5 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE RIDES NORTHEAST ALONG A COLD FRONT STRETCHING FROM THE CENTRAL GULF COAST INTO QUEBEC INTO MONDAY. ITS ASSOCIATED WARM FRONT LIFTS THROUGH THE AREA TONIGHT...FOLLOWED BY ITS TRAILING ARCTIC FRONT BY MONDAY AFTERNOON. ARCTIC AIR THEN POURS INTO THE REGION INTO THE MIDDLE OF THE WEEK. THE WEATHER WILL BE UNSETTLED FOR THE LATTER PART OF THE WEEK AS A WEAK FRONTAL BOUNDARY STALLS NEAR THE REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LIGHT FREEZING RAIN AND LIGHT FREEZING DRIZZLE CONTINUES TO SPREAD INLAND...WHERE TEMPS ARE IN THE TEENS TO MID 20S. LONG ISLAND IS BEGINNING TO RISE ABOVE FREEZING...BUT THOSE TEMPS ARE TAKEN AT 6 FT...AND WITH SNOWPACK ON THE GROUND...THINK TEMPS AT THE GROUND ARE STILL AT OR BELOW FREEZING. WILL TAKE SOME TIME FOR THE WARMER AIR TO SPREAD NORTH...AS SE WINDS DO NOT LOOK TO INCREASE UNTIL LATE AFTERNOON/EARLY EVENING. AS SUCH...MODIFIED THE FREEZING RAIN ADVISORY TO EXTEND FOR NYC...NEARBY NJ...AND LONG ISLAND UNTIL 4 PM AND EVERYBODY ELSE UNTIL 7 PM. LATEST HRRR AND 12Z NAM INDICATING A PERIOD OF DRYING BY FROM 21Z-00Z...SO IT IS LIKELY THAT THE ADVISORY CAN BE CANCELLED PRIOR TO THAT. TRAVEL IS TREACHEROUS...AND THERE HAVE BEEN NUMEROUS TRAFFIC ACCIDENTS REPORTED ACROSS THE AREA DUE TO THE ICED UP ROADS. ICE ACCUMULATIONS SHOULD AVERAGE A TRACE TO MAYBE A FEW HUNDREDTHS OF AN INCH. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... ANY LINGERING FREEZING RAIN OVER ORANGE COUNTY SHOULD TURN TO ALL RAIN BY EARLY EVENING. ISENTROPIC LIFT STEADILY INCREASES IN DEPTH/SATURATION...COUPLED WITH A 45-60 KT LOW LEVEL JST PASSING OVER THE REGION...WILL SEE AN INCREASE IN THE COVERAGE AND INTENSITY OF THE RAIN WILL DO LIKEWISE FROM TONIGHT INTO MONDAY MORNING. SEE HYDROLOGY SECTION OF THE AFD FOR DETAILS AND IMPACT. RAINFALL COMES TO AN END WITH THE PASSAGE OF THE ARCTIC FRONT MAINLY DURING THE MORNING HOURS ON MONDAY. COULD SEE SOME SHOWERS IMMEDIATELY IN ITS WAKE - EITHER SHRA/SHSN OR BOTH DEPENDING ON EXACTLY HOW FAST THE TEMPERATURES FALL OF NEAR THE SURFACE. HAVE THE POTENTIAL FOR A FLASH FREEZE IN THE AFTERNOON - ESPECIALLY IN AREAS FROM NYC ON N/W WHERE TEMPERATURES FALL INTO THE TEENS/AROUND 20 BY EVENING. LESS CERTAIN FARTHER E WHERE TEMPERATURES ONLY FALL INTO THE 20S. BITTERLY COLD AIR THEN MOVES IN MONDAY NIGHT-TUESDAY NIGHT... LOWS MONDAY NIGHT FROM THE LOW SINGLE DIGITS FAR NW TO MID TEENS FAR E...HIGHS TUESDAY FROM THE UPPER SINGLE DIGITS FAR NW TO AROUND 20 FAR E...AND LOWS TUESDAY NIGHT MAINLY FROM 5 BELOW TO 5 ABOVE - A TAD HIGHER IN NYC/THE TWIN FORKS/AND AT THE IMMEDIATE COAST. WINDS TO POSSIBLY WIND ADVISORY LEVELS ACROSS NYC/LONG ISLAND AND HIGHER ELEVATIONS ACROSS THE INTERIOR...AND JUST BELOW ADVISORY LEVELS ELSEWHERE WILL PRODUCE POTENTIALLY DANGEROUS WIND CHILLS MONDAY NIGHT-TUESDAY NIGHT. WIND CHILLS MONDAY NIGHT WILL FALL TO -15 TO -20 ACROSS NW INTERIOR ZONES...-5 T0 -15 ACROSS MOST OF THE REMAINDER OF THE AREA...EXCEPT AROUND 0 FAR EASTERN AREAS. WIND CHILLS MODERATE SLIGHTLY DURING THE DAY ON TUESDAY TO FROM -15 TO 0 (HIGHEST FAR E). DIMINISHING WINDS TUESDAY NIGHT WILL LIMIT WIND CHILLS TO GENERALLY -5 TO -15 (LOWEST FAR NW)...EXCEPT -5 TO 0 FAR E ZONES. WIND CHILL ADVISORIES WILL LIKELY BE NEEDED FOR WESTERN NE NJ ZONES AND MOST OF THE LOWER HUDSON VALLEY FROM MONDAY NIGHT INTO TUESDAY MORNING. STILL SOME UNCERTAINTY ON EXACTLY HOW THE WINDS AND TEMPERATURES PLAY OUT - GUIDANCE TENDS TO BE TOO WARM IN EXTREME EVENTS LIKE THIS - ESPECIALLY THIS FAR OUT - SO EVEN THOUGH IT WAS UNDERCUT USING A BLEND OF MODEL 2-METER TEMPERATURES NOT SURE IF HAVE GONE COLD ENOUGH. BECAUSE OF THIS - STILL WILL HIGHLIGHT THE CHANCE OF WIND CHILLS AROUND -25 ACROSS INTERIOR ZONES IN THE HWO MONDAY NIGHT/TUESDAY MORNING. THE STRONG WNW WINDS AND COLD AIR IN THE LOW LEVELS FROM MONDAY NIGHT INTO TUESDAY NIGHT WILL ALSO CREATE CONDITIONS RIPE FOR SOUND EFFECT SNOW. AS TIME GOES ON CONFIDENCE INCREASES - SO HAVE INCREASED POPS OVER THE TWIN FORKS TO CHANCE ON TUESDAY AFTERNOON - AS SUGGESTED BY GFS AND ECMWF. GIVEN DEGREE OF SEPARATION BETWEEN 850 TEMPERATURE AND WATER TEMPERATURE (25-30C) WOULD NOT BE SURPRISED THAT COULD END UP WITH SOME ACCUMULATING SNOW ACROSS EASTERN PORTIONS OF THE ISLAND - POSSIBLY WITH SOME IMPRESSIVE SNOW BURSTS. ONCE AGAIN STILL SOME UNCERTAINTY - SO DO NOT WANT TO GO TOO FAR IN ANY DIRECTION ON THIS QUITE YET. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... FAST WSW FLOW ALOFT WEDNESDAY/WEDNESDAY NIGHT THEN WEAK RIDGING BUILDS ACROSS ON THURSDAY. DO HAVE THE SLIGHT FOR SOME SNOW ACROSS MAINLY INTERIOR ZONES IN RESPONSE TO A PASSING SHORTWAVE AND WEAK WARM ADVECTION. BETTER CHANCE FOR SOME LIGHT SNOW IS THURSDAY NIGHT WHERE A DEEPER SHORTWAVE CROSSES THE AREA. ANOTHER SHORTWAVE MOVES IN ON FRIDAY - WITH POTENTIAL FOR SNOW N AND RAIN/SNOW SOUTH. SOME UNCERTAINTY ON HOW WARM LOW LEVELS GET - SO USED BLEND OF GFS/ECMWF FOR NOW. A FRONTAL BOUNDARY STALLS NEAR BY TO CLOSE THE WEEK. WHETHER IT IS TO THE N OR S AND HOW WAVES OF PRECIPITATION INTERACT WITH IT ARE UNCERTAIN SO HAVE KEPT POPS RELATIVELY LOW FOR NOW AND KEPT THINGS SNOW TO RAIN N AND A MIX TO RAIN S FROM FRIDAY NIGHT INTO SATURDAY. TEMPERATURES WERE BASED ON A BLEND OF ALL AVAILABLE GUIDANCE AND START OUT WELL BELOW NORMAL - MODERATE TO NEAR NORMAL BY FRIDAY AND TO ABOVE NORMAL BY SATURDAY. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... A WARM FRONT APPROACHES THIS AFTERNOON...FOLLOWED BY A COLD FRONT TONIGHT AND EARLY MONDAY. LOW END MVFR OR IFR CONDITIONS LIKELY THIS AFTERNOON...WITH IFR OR LIFR TONIGHT IN LOW CLOUDS AND FOG. KJFK AND KISP HAVE WARMED CLOSE TO OR JUST ABOVE FREEZING. FREEZING RAIN MOST TERMINALS SHOULD GRADUALLY CHANGE TO PLAIN RAIN...21-00Z TIME FRAME. INTERIOR AIRPORTS MAY TAKE A LITTLE LONGER FOR THE TRANSITION TO TAKE PLACE. PERIODS OF RAIN EXPECTED TONIGHT. AS FOR WINDS...LIGHT AND VARIABLE OR LIGHT EAST THROUGH LATE THIS AFTERNOON AND INTO THE EVENING WILL BECOME SOUTHERLY TONIGHT. SPEEDS INCREASE TONIGHT AHEAD OF THE COLD FRONT. WINDS SHIFT AFTER 12-15Z MONDAY MORNING BEHIND THE FRONT. GUSTS 20 TO 30 KTS EXPECTED BEHIND THE FRONT. LOW LEVEL WIND SHEAR 45 TO 50 KTS EXPECTED AFTER MIDNIGHT TONIGHT INTO THE EARLY MORNING...MAINLY BEFORE 12Z. .OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY... .MON AFTERNOON-TUE...VFR. W WINDS G25-35KT...HIGHEST MON NIGHT-TUE. .WED...VFR. W WINDS G20KT IN THE MORNING. .THU...VFR. CHANCE OF MVFR OR LOWER CONDITIONS IN LIGHT SNOW BY LATE DAY OR AT NIGHT. .FRI...SUB-VFR POSSIBLE EARLY IN SNOW TO RAIN. && .MARINE... SCA WILL REMAIN UP FOR THE 2 EASTERN OCEAN WATERS INTO THIS EVENING FOR 4-6 FT SEAS. INCREASING SE FLOW TONIGHT IN COMBINATION WITH RESIDUAL SWELLS SHOULD PUSH OCEAN SEAS BACK OVER 5 FT TONIGHT. GUSTS OVER 25 KT SHOULD FOLLOW LATE TONIGHT INTO MON MORNING. SCA ALSO IN EFFECT FOR THE OCEAN FOR THIS TIME FRAME. GALES ARE EXPECTED AFTER COLD FROPA ON MON...BUT TIMING IS IN QUESTION. THEY COULD START AS EARLY AS MON AFTERNOON BUT THINK GREATER LIKELIHOOD EXISTS FOR MON NIGHT-TUE...AND A GALE WATCH HAS BEEN ISSUED FOR THE OCEAN FOR THIS TIME FRAME. GALES ARE ALSO LIKELY ON THE HARBOR/SOUND/BAYS FOR PART OF THIS TIME...AVE HELD OFF ON WATCH THERE FOR NOW. THE COMBINATION OF COLD WATER TEMPERATURES AND STRONG WINDS WILL LIKELY LEAD TO FREEZING SPRAY MON NIGHT-TUE NIGHT...AND A FREEZING SPRAY ADVISORY MAY EVENTUALLY BE NEEDED. BLOWOUT TIDES WILL ALSO BE A CONCERN ON THE WESTERN SOUND AND THE BAYS OF LONG ISLAND DURING THE TUE NIGHT LOW TIDE CYCLE. SCA CONDS ARE LIKELY INTO WED MORNING ON THE NON-OCEAN WATERS WITH SEAS REMAINING ABOVE 5 FT ON THE OCEAN WATERS INTO WED NIGHT. && .HYDROLOGY... WIDESPREAD RAIN OVER THE REGION...MAINLY FROM THIS AFTERNOON INTO EARLY MONDAY AFTERNOON...WILL RESULT IN 2/3 TO 9/10 INCH QPF. THE COMBINATION OF LOCALLY HEAVY RAIN AND MELTING SNOW MAY RESULT IN MINOR FLOODING OF URBAN AND POOR DRAINING LOCATIONS. && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR CTZ005>012. NY...FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NYZ072>075-078>081-176>179. FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR NYZ067>071. NJ...FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ006-106-108. FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR NJZ002- 004-103>105-107. MARINE...GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON FOR ANZ350-353-355. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST MONDAY FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT NEAR TERM...MPS SHORT TERM...MALOIT LONG TERM...MALOIT AVIATION...PW MARINE...GOODMAN HYDROLOGY...MALOIT EQUIPMENT...
AREA FORECAST DISCUSSION
NWS NEW YORK NY
1128 AM EST SUN JAN 5 2014 .SYNOPSIS... AN AREA OF LOW PRESSURE RIDES NORTHEAST ALONG A COLD FRONT STRETCHING FROM THE CENTRAL GULF COAST INTO QUEBEC INTO MONDAY. ITS ASSOCIATED WARM FRONT LIFTS THROUGH THE AREA TONIGHT...FOLLOWED BY ITS TRAILING ARCTIC FRONT BY MONDAY AFTERNOON. ARCTIC AIR THEN POURS INTO THE REGION INTO THE MIDDLE OF THE WEEK. THE WEATHER WILL BE UNSETTLED FOR THE LATTER PART OF THE WEEK AS A WEAK FRONTAL BOUNDARY STALLS NEAR THE REGION. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... LIGHT FREEZING RAIN AND LIGHT FREEZING DRIZZLE CONTINUES TO SPREAD INLAND...WHERE TEMPS ARE IN THE TEENS TO MID 20S. LONG ISLAND IS BEGINNING TO RISE ABOVE FREEZING...BUT THOSE TEMPS ARE TAKEN AT 6 FT...AND WITH SNOWPACK ON THE GROUND...THINK TEMPS AT THE GROUND ARE STILL AT OR BELOW FREEZING. WILL TAKE SOME TIME FOR THE WARMER AIR TO SPREAD NORTH...AS SE WINDS DO NOT LOOK TO INCREASE UNTIL LATE AFTERNOON/EARLY EVENING. AS SUCH...MODIFIED THE FREEZING RAIN ADVISORY TO EXTEND FOR NYC...NEARBY NJ...AND LONG ISLAND UNTIL 4 PM AND EVERYBODY ELSE UNTIL 7 PM. LATEST HRRR AND 12Z NAM INDICATING A PERIOD OF DRYING BY FROM 21Z-00Z...SO IT IS LIKELY THAT THE ADVISORY CAN BE CANCELLED PRIOR TO THAT. TRAVEL IS TREACHEROUS...AND THERE HAVE BEEN NUMEROUS TRAFFIC ACCIDENTS REPORTED ACROSS THE AREA DUE TO THE ICED UP ROADS. ICE ACCUMULATIONS SHOULD AVERAGE A TRACE TO MAYBE A FEW HUNDREDTHS OF AN INCH. && .SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/... ANY LINGERING FREEZING RAIN OVER ORANGE COUNTY SHOULD TURN TO ALL RAIN BY EARLY EVENING. ISENTROPIC LIFT STEADILY INCREASES IN DEPTH/SATURATION...COUPLED WITH A 45-60 KT LOW LEVEL JST PASSING OVER THE REGION...WILL SEE AN INCREASE IN THE COVERAGE AND INTENSITY OF THE RAIN WILL DO LIKEWISE FROM TONIGHT INTO MONDAY MORNING. SEE HYDROLOGY SECTION OF THE AFD FOR DETAILS AND IMPACT. RAINFALL COMES TO AN END WITH THE PASSAGE OF THE ARCTIC FRONT MAINLY DURING THE MORNING HOURS ON MONDAY. COULD SEE SOME SHOWERS IMMEDIATELY IN ITS WAKE - EITHER SHRA/SHSN OR BOTH DEPENDING ON EXACTLY HOW FAST THE TEMPERATURES FALL OF NEAR THE SURFACE. HAVE THE POTENTIAL FOR A FLASH FREEZE IN THE AFTERNOON - ESPECIALLY IN AREAS FROM NYC ON N/W WHERE TEMPERATURES FALL INTO THE TEENS/AROUND 20 BY EVENING. LESS CERTAIN FARTHER E WHERE TEMPERATURES ONLY FALL INTO THE 20S. BITTERLY COLD AIR THEN MOVES IN MONDAY NIGHT-TUESDAY NIGHT... LOWS MONDAY NIGHT FROM THE LOW SINGLE DIGITS FAR NW TO MID TEENS FAR E...HIGHS TUESDAY FROM THE UPPER SINGLE DIGITS FAR NW TO AROUND 20 FAR E...AND LOWS TUESDAY NIGHT MAINLY FROM 5 BELOW TO 5 ABOVE - A TAD HIGHER IN NYC/THE TWIN FORKS/AND AT THE IMMEDIATE COAST. WINDS TO POSSIBLY WIND ADVISORY LEVELS ACROSS NYC/LONG ISLAND AND HIGHER ELEVATIONS ACROSS THE INTERIOR...AND JUST BELOW ADVISORY LEVELS ELSEWHERE WILL PRODUCE POTENTIALLY DANGEROUS WIND CHILLS MONDAY NIGHT-TUESDAY NIGHT. WIND CHILLS MONDAY NIGHT WILL FALL TO -15 TO -20 ACROSS NW INTERIOR ZONES...-5 T0 -15 ACROSS MOST OF THE REMAINDER OF THE AREA...EXCEPT AROUND 0 FAR EASTERN AREAS. WIND CHILLS MODERATE SLIGHTLY DURING THE DAY ON TUESDAY TO FROM -15 TO 0 (HIGHEST FAR E). DIMINISHING WINDS TUESDAY NIGHT WILL LIMIT WIND CHILLS TO GENERALLY -5 TO -15 (LOWEST FAR NW)...EXCEPT -5 TO 0 FAR E ZONES. WIND CHILL ADVISORIES WILL LIKELY BE NEEDED FOR WESTERN NE NJ ZONES AND MOST OF THE LOWER HUDSON VALLEY FROM MONDAY NIGHT INTO TUESDAY MORNING. STILL SOME UNCERTAINTY ON EXACTLY HOW THE WINDS AND TEMPERATURES PLAY OUT - GUIDANCE TENDS TO BE TOO WARM IN EXTREME EVENTS LIKE THIS - ESPECIALLY THIS FAR OUT - SO EVEN THOUGH IT WAS UNDERCUT USING A BLEND OF MODEL 2-METER TEMPERATURES NOT SURE IF HAVE GONE COLD ENOUGH. BECAUSE OF THIS - STILL WILL HIGHLIGHT THE CHANCE OF WIND CHILLS AROUND -25 ACROSS INTERIOR ZONES IN THE HWO MONDAY NIGHT/TUESDAY MORNING. THE STRONG WNW WINDS AND COLD AIR IN THE LOW LEVELS FROM MONDAY NIGHT INTO TUESDAY NIGHT WILL ALSO CREATE CONDITIONS RIPE FOR SOUND EFFECT SNOW. AS TIME GOES ON CONFIDENCE INCREASES - SO HAVE INCREASED POPS OVER THE TWIN FORKS TO CHANCE ON TUESDAY AFTERNOON - AS SUGGESTED BY GFS AND ECMWF. GIVEN DEGREE OF SEPARATION BETWEEN 850 TEMPERATURE AND WATER TEMPERATURE (25-30C) WOULD NOT BE SURPRISED THAT COULD END UP WITH SOME ACCUMULATING SNOW ACROSS EASTERN PORTIONS OF THE ISLAND - POSSIBLY WITH SOME IMPRESSIVE SNOW BURSTS. ONCE AGAIN STILL SOME UNCERTAINTY - SO DO NOT WANT TO GO TOO FAR IN ANY DIRECTION ON THIS QUITE YET. && .LONG TERM /WEDNESDAY THROUGH SATURDAY/... FAST WSW FLOW ALOFT WEDNESDAY/WEDNESDAY NIGHT THEN WEAK RIDGING BUILDS ACROSS ON THURSDAY. DO HAVE THE SLIGHT FOR SOME SNOW ACROSS MAINLY INTERIOR ZONES IN RESPONSE TO A PASSING SHORTWAVE AND WEAK WARM ADVECTION. BETTER CHANCE FOR SOME LIGHT SNOW IS THURSDAY NIGHT WHERE A DEEPER SHORTWAVE CROSSES THE AREA. ANOTHER SHORTWAVE MOVES IN ON FRIDAY - WITH POTENTIAL FOR SNOW N AND RAIN/SNOW SOUTH. SOME UNCERTAINTY ON HOW WARM LOW LEVELS GET - SO USED BLEND OF GFS/ECMWF FOR NOW. A FRONTAL BOUNDARY STALLS NEAR BY TO CLOSE THE WEEK. WHETHER IT IS TO THE N OR S AND HOW WAVES OF PRECIPITATION INTERACT WITH IT ARE UNCERTAIN SO HAVE KEPT POPS RELATIVELY LOW FOR NOW AND KEPT THINGS SNOW TO RAIN N AND A MIX TO RAIN S FROM FRIDAY NIGHT INTO SATURDAY. TEMPERATURES WERE BASED ON A BLEND OF ALL AVAILABLE GUIDANCE AND START OUT WELL BELOW NORMAL - MODERATE TO NEAR NORMAL BY FRIDAY AND TO ABOVE NORMAL BY SATURDAY. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... A WARM FRONT APPROACHES TODAY...FOLLOWED BY A COLD FRONT TONIGHT AND MONDAY. MVFR CIGS LATE THIS MORNING. FREEZING RAIN OR DRIZZLE MOST AIRPORTS. TIMING OF PLAIN RAIN COULD BE OFF BY AN HOUR OR TWO. MOST WATCH SFC TEMPS AS THEY RISE TOWARD THE FREEZING MARK. STILL EXPECT IFR OR EVEN LIFR LATER THIS AFTERNOON IN LIGHT RAIN. LOW CLOUDS..RAIN AND FOG EXPECTED TONIGHT. LIGHT WINDS ARE EXPECTED TO TURN TOWARD THE E-SE THIS AFTERNOON...THEN BECOME SE 10-15 KT THIS EVENING. LOW LEVEL WIND SHEAR INCLUDED FOR TONIGHT AS WINDS ALOFT STRENGTHEN. .OUTLOOK FOR 12Z MONDAY THROUGH THU... .MON MORNING...IFR OR LIFR IN RAIN AND FOG. .MON AFTERNOON-TUE...BECOMING VFR. W WINDS G25-35KT...HIGHEST MON NIGHT-TUE. .WED...VFR. W WINDS G20KT IN THE MORNING. .THU...VFR. CHANCE OF MVFR OR LOWER CONDS IN LIGHT SNOW BY LATE DAY OR AT NIGHT. && .MARINE... SCA WILL REMAIN UP FOR THE 2 EASTERN OCEAN WATERS INTO THIS EVENING FOR 4-6 FT SEAS. INCREASING SE FLOW TONIGHT IN COMBINATION WITH RESIDUAL SWELLS SHOULD PUSH OCEAN SEAS BACK OVER 5 FT TONIGHT. GUSTS OVER 25 KT SHOULD FOLLOW LATE TONIGHT INTO MON MORNING. SCA ALSO IN EFFECT FOR THE OCEAN FOR THIS TIME FRAME. GALES ARE EXPECTED AFTER COLD FROPA ON MON...BUT TIMING IS IN QUESTION. THEY COULD START AS EARLY AS MON AFTERNOON BUT THINK GREATER LIKELIHOOD EXISTS FOR MON NIGHT-TUE...AND A GALE WATCH HAS BEEN ISSUED FOR THE OCEAN FOR THIS TIME FRAME. GALES ARE ALSO LIKELY ON THE HARBOR/SOUND/BAYS FOR PART OF THIS TIME...AVE HELD OFF ON WATCH THERE FOR NOW. THE COMBINATION OF COLD WATER TEMPERATURES AND STRONG WINDS WILL LIKELY LEAD TO FREEZING SPRAY MON NIGHT-TUE NIGHT...AND A FREEZING SPRAY ADVISORY MAY EVENTUALLY BE NEEDED. BLOWOUT TIDES WILL ALSO BE A CONCERN ON THE WESTERN SOUND AND THE BAYS OF LONG ISLAND DURING THE TUE NIGHT LOW TIDE CYCLE. SCA CONDS ARE LIKELY INTO WED MORNING ON THE NON-OCEAN WATERS WITH SEAS REMAINING ABOVE 5 FT ON THE OCEAN WATERS INTO WED NIGHT. && .HYDROLOGY... WIDESPREAD RAIN OVER THE REGION...MAINLY FROM THIS AFTERNOON INTO EARLY MONDAY AFTERNOON...WILL RESULT IN 2/3 TO 9/10 INCH QPF. THE COMBINATION OF LOCALLY HEAVY RAIN AND MELTING SNOW MAY RESULT IN MINOR FLOODING OF URBAN AND POOR DRAINING LOCATIONS. && .EQUIPMENT... THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DUE TO INTERFERENCE ISSUES WITH THE U.S. COAST GUARD EMERGENCY BROADCAST CHANNEL...THE NEW YORK CITY NOAA ALL HAZARDS WEATHER RADIO STATION KWO35 IS OUT OF SERVICE. DURING THE TIME...THE TRANSMITTER MAY BE RETURNED TO SERVICE INTERMITTENTLY FOR USE OF THE NOAA ALL HAZARDS WEATHER RADIO DURING POTENTIALLY DANGEROUS WEATHER SITUATIONS...FOR ROUTINE WEEKLY TEST OF THE WARNING SYSTEM...AND TO DETERMINE IF THE INTERFERENCE ISSUE HAS BEEN RESOLVED. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR CTZ005>012. NY...FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NYZ072>075-078>081-176>179. FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR NYZ067>071. NJ...FREEZING RAIN ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR NJZ006-106-108. FREEZING RAIN ADVISORY UNTIL 7 PM EST THIS EVENING FOR NJZ002- 004-103>105-107. MARINE...GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON FOR ANZ350-353-355. SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 PM EST MONDAY FOR ANZ355. SMALL CRAFT ADVISORY UNTIL 6 PM EST MONDAY FOR ANZ350-353. && $$ SYNOPSIS...MALOIT NEAR TERM...MPS SHORT TERM...MALOIT LONG TERM...MALOIT AVIATION...GOODMAN MARINE...GOODMAN HYDROLOGY...MALOIT EQUIPMENT...
AREA FORECAST DISCUSSION...UPDATED
NWS CHICAGO/ROMEOVILLE IL
1134 AM CST SUN JAN 5 2014 .DISCUSSION... 1130 AM CST HAVE MADE SOME ADJUSTMENTS TO SNOWFALL FORECASTS BASED ON THE PLETHORA OF REPORTS THROUGH EARLY THIS MORNING...AND BETTER REFINING THE AREAL COVERAGE OF THE HEAVIEST SNOW THIS AFTERNOON. NO CHANGES MADE TO HEADLINES BESIDES CANCELLING THE WINTER WEATHER ADVISORY FOR FAR NORTHERN IL. PICTURESQUE WATER VAPOR IMAGE LATE THIS MORNING WITH THE STRONG UPPER TROUGH MOVING EAST FROM THE OZARKS AND A COUPLED UPPER JET IN ADVANCE DIRECTLY OVERHEAD AND OWING TO SUBSTANTIAL LIFT. THIS HAS ENABLED MODERATE TO HEAVY SNOW TO EXPAND QUICKLY NORTHEAST FROM SOUTHWEST/CENTRAL IL INTO THE CWA...MAINLY EAST OF I-55...WITH MOST OBSERVATIONS AT ONE HALF MILE VISIBILITY AND OCCASIONALLY A FEW LOWER. THIS IS ALONG THE 850MB TROUGH/DEVELOPING LOW AND THE FAVORED -5C ISOTHERM IN THIS DEVELOPING DEFORMATION AREA OF A SYSTEM. AS THIS CONTINUES TO GRADUALLY SHIFT EAST...IT WILL TAKE THE BEST MOISTURE WITH IT AND SHOULD ALLOW FOR THE SNOW RATIOS TO BETTER ACROSS THE SOUTHEAST FORECAST AREA. REPORTS HAVE GENERALLY BEEN OF A VERY WET SNOW THUS FAR. IN ADDITION...BANDED POTENTIAL ACROSS THE SOUTHEAST HALF OF THE CWA WILL IMPROVE AS WELL AND HAVE SEEN TRENDS OF THAT ON RADAR WITH STRIPS OF GREATER THAN 25DBZ OCCASIONALLY DEVELOPING. EVEN HAVE SEEN TEMPORARY ONE QUARTER MILE VISIBILITY ALL THE WAY UP AT ORD AS OF 1125 AM WITH SUCH A TEMPORARY BAND. JUST GIVEN THE DEFORMATION PLACEMENT AND SHORT TERM FORECASTS OF FRONTOGENESIS AND ELEVATED INSTABILITY...SEE NO REASON THESE WILL NOT CONTINUE TO UNDULATE AROUND AND BE MOST PERSISTENT IN THE FAR SOUTHEAST FORECAST AREA. SO BELIEVE THAT ADDITIONAL 1-3 INCHES SHOULD BE SEEN BETWEEN I-88 AND I-55...INCLUDING CHICAGO...FOR STORM TOTALS OF 5-9 INCHES /7-9 IN CHICAGO/. WIDESPREAD 3-6 ADDITIONAL INCHES SHOULD BE SEEN ACROSS THE SOUTHEAST FORECAST AREA THIS AFTERNOON...FOR GRAND TOTALS OF 6-12 BASED ON WHAT HAS FALLEN. THE HIGHEST TOTAL AMOUNTS LOOK TO BE IN NORTHERN LAKE AND PORTER COUNTIES WHICH HAD RECEIVED 4-6 LAST NIGHT...AND WHERE LAKE CONVERGENCE CONTINUES TO FEED SOME ENHANCEMENT INTO THE AREA. LAKE AND PORTER COUNTIES ALSO IS MOST VULNERABLE TO THE FRICTIONLESS WIND FETCH DOWN THE LAKE FOR GUSTS OF 40 MPH WHICH WOULD LEAD TO CONSIDERABLE BLOWING SNOW AS WELL. ALSO LAKE AND PORTER COUNTIES ARE ALREADY RECEIVING SOME OF THE LIGHTER/LOWER WATER CONTENT SNOW AS IT IS SO THEY WILL HAVE A HIGHER BASE. WILL CONTINUE TO MONITOR CLOSELY IF A BLIZZARD WARNING IS NEEDED THERE AS A COUPLE MAJOR INTERSTATES ARE NOT FAR FROM THE LAKE SHORE. ALSO WILL CONTINUE TO MONITOR FURTHER SOUTH TOWARD KANKAKEE AND PONTIAC AS THE SYNOPTIC ISALLOBARIC COUPLET DEVELOPS AND PASSES LATE THIS AFTERNOON AND EVE IN TANDEM WITH THE GREATEST COLD AIR ADVECTION. AT THIS TIME THE THOUGHT IS MUCH OF THIS EARLY SNOW HAS BEEN TOO WET OF A CONTENT TO BE WIDESPREAD BLOWING...AND ONCE IT DOES THE ACTUAL FALLING SNOW WILL HAVE CEASED. SO THAT MAY RESULT IN MORE GROUND BLIZZARD TYPE CONDITIONS. EITHER WAY...TRAVEL WILL CONTINUE TO BE TREACHEROUS IN THE WINTER STORM WARNING AREA. NO CHANGES MADE TO TIMING OF COLD AIR ARRIVAL AND MIN WIND CHILLS AT THIS TIME. MTF && .PREV DISCUSSION... 338 AM CST COMPLEX...HIGH IMPACT WINTER WEATHER EVENT UNDERWAY FOR NORTHERN ILLINOIS AND NORTHWEST INDIANA. FOR THE SHORT TERM...THE FOCUS IS THE POST-FRONTAL SNOW BAND EXTENDING FROM CENTRAL MISSOURI...THROUGH ILLINOIS AND INDIANA AND INTO LOWER MICHIGAN. AS OF 3AM CST...THE COLD FRONT WAS PUSHING INTO NWRN INDIANA AND EAST-CENTRAL ILLINOIS. THE ONGOING SNOW IS LARGELY POST-FRONTAL ALONG AN ELEVATED F-GEN BAND. LATEST RADAR IMAGERY INDICATES NARROW EMBEDDED HEAVIER BANDS WITH AN ENHANCED BAND FROM GARY TO PONTIAC. SNOWFALL RATES OF 1/2 INCH PER HOUR ARE LIKELY WITHIN THE HEAVIER BANDS...WITH STEADY LIGHTER SNOW COVERING THE REMAINDER OF THE CWA. THE POST FRONTAL SNOW SHOULD PERSIST FOR THE REMAINDER OF THE NIGHT AND INTO THE MORNING HOURS. SOME OF THE HI RES GUIDANCE IS SUGGESTING A BRIEF LULL TO THE STEADIER SNOW BEFORE THE WARM ADVECTION SNOW KICKS IN WITH THE SRN STREAM SHORTWAVE LIFTING UP FROM THE SOUTHWEST. HAVE ACTUALLY MADE LITTLE SIGNIFICANT CHANGE TO THE GOING FORECAST AND WINTER WEATHER HEADLINES...BUT STILL HAVE SOME CONCERN ABOUT THE NECESSITY TO UPGRADE AT LEAST A PORTION OF THE WINTER STORM WARNING TO A BLIZZARD WARNING FOR LATE THIS AFTERNOON THROUGH TONIGHT. DURING THIS PERIOD...MUCH OF THE AREA WILL SEE NORTH WINDS GUSTING TO 30-35 MPH. SO...WILL MAINTAIN MENTION OF BLOWING SNOW FOR THE ENTIRE CWA WITH...ONCE AGAIN...OPEN AREAS WITH EAST-WEST ORIENTED ROADS SEEING THE GREATEST IMPACT. BY THE TIME THAT THE WARM ADVECTION SNOW GETS UNDERWAY...THE SERN PORTIONS OF THE CWA...GENERALLY SOUTH AND EAST OF A LINE FROM GARY TO PONTIAC SHOULD SEE THE HEAVIEST SNOW...WITH AMOUNTS GRADUALLY TAPERING OFF TO THE NORTH. THE COMBINATION OF FALLING SNOW AND STRONG WINDS COULD VERY LIKELY PRODUCE BLIZZARD CONDITIONS...BUT WILL HOLD OFF ON UPGRADING THIS PORTION OF THE AREA TO A BLIZZARD WARNING FOR NOW...AND MONITOR THE ONSET TIMING OF THE HEAVIER SNOWFALL RATES WITH THE WARM ADVECTION SNOW. THE HIGH RES MODEL GUIDANCE STILL WANTS TO DEVELOP A LAKE EFFECT PLUME POINTING INTO LAKE AND PORTER COUNTIES IN NORTHWESTERN INDIANA LATE THIS AFTERNOON AND EARLY THIS EVENING...WHICH COULD FURTHER ENHANCE SNOWFALL RATES AND LIKELY REDUCING VISIBILITY TO NEAR ZERO AT TIMES. SO...MANY OF THE INGREDIENTS NECESSARY FOR BLIZZARD CONDITIONS ARE COMING TOGETHER...THE MAIN QUESTIONS BEING TIMING AND AREA EXTENT STILL UNCERTAIN ENOUGH TO HOLD OFF ON A BLIZZARD WARNING FOR NOW. AND THEN THERE IS THE ARCTIC BLAST. TEMPERATURES ARE ALREADY DROPPING OFF OVER THE NWRN PORTIONS OF THE CWA...WITH ROCKFORD DOWN TO 18F AS OF 3AM CST. THE TEMPERATURE TREND FOR THE REMAINDER OF THE DAY WILL BE DOWNWARD...WITH DAILY HIGHS LIKELY ALREADY OCCURRING. THE TEMPERATURE FORECAST ALSO LOOKS IN LINE WITH PREVIOUS THINKING WITH TEMPS LIKELY DROPPING BELOW 0F OVER THE ROCKFORD AREA BY LATE THIS AFTERNOON AND THE COLD AIR CONTINUE TO OVERSPREAD THE AREA THROUGH SUNDAY NIGHT...WITH THE HAZARDOUSLY COLD AIR REMAINING OVER THE AREA INTO WEDNESDAY. AGAIN...WITH VERY CONSISTENT GUIDANCE WITH RESPECT TO THE COLD...STILL EXPECT THAT LOWS MONDAY AND TUESDAY MORNING WILL DROP TO -15 TO -20F OVER MUCH OF THE AREA...WITH ONLY THE IMMEDIATE LAKEFRONT SEEING LOWS ABOVE -15F...BUT STILL WELL BELOW ZERO. HIGHS FOR MONDAY ARE STILL EXPECTED TO FLIRT WITH ALL TIME RECORD LOW MAX TEMPS. THIS IS PROBABLY THE ONLY AREA OF THE FORECAST WHICH IS SEEING SOME FLIP-FLOPPING AND HAVE ADJUSTED MAX TEMPS FOR MONDAY BACK DOWN A FEW DEGREES SINCE THE VERY STRONG HIGH WILL BE SLIDING OVER THE WESTERN PLAINS AS THE SRN STREAM LOW IS BOMBING OUT OVER QUEBEC. THIS SCENARIO WILL SET UP AN UNIMPEDED FETCH OF COLD ARCTIC AIR...SO STILL FEEL THAT MUCH OF THE LARGER SCALE MODEL GUIDANCE IS ON TARGET IN KEEPING MAX TEMPS FOR MUCH OF THE CWA AT -15F OR POSSIBLY A TOUCH LOWER. AGAIN...TEMPS OVER THE URBANIZED CHICAGO METRO AREA AND IMMEDIATE LAKE FRONT SHOULD BE A TAD MORE MODERATE...BUT EVEN IN THESE LOCATIONS...TEMPS WILL STRUGGLE TO REACH -10F. KREIN TUESDAY THROUGH SATURDAY... MAIN FORECAST CONCERNS/CHALLENGES IN THIS PERIOD ARE WITH THE LINGERING COLD AIR MASS...CHANCE FOR SNOW BY MID WEEK...AND THEN A CONTINUED WARMING TREND EXPECTED INTO THE WEEKEND. AT THE START OF THE PERIOD...MODEL GUIDANCE IN PRETTY GOOD AGREEMENT WITH RESPECT TO OVERALL PATTERN ACROSS THE REGION. WITH THE LARGE AND HIGHLY AMPLIFIED UPPER LEVEL TROUGH SHIFTING TO THE EAST...LINGERING SURFACE TROUGH OVER THE GREAT LAKES REGION WILL SLOWLY SHIFT EAST AS HIGH PRESSURE SPREADS OVER THE AREA. ISSUES DURING THIS TIME FRAME REMAIN WITH THE COLD AIR MASS IN PLACE...DESPITE SOME SLIGHT MODERATING WITH THIS COLD AIR. EXPECT WELL BELOW ZERO TEMPS TO SLOWLY RISE THROUGH THE MORNING TIME FRAME...BUT WITH WIND CHILLS STILL VERY MUCH IN SUPPORT OF THE CURRENT WIND CHILL WARNING THAT IS IN EFFECT THROUGH MID DAY TUESDAY. MADE SLIGHT CHANGES TO HIGH TEMPS ON TUESDAY WITH HIGHS STILL EXPECTED TO HOVER RIGHT AROUND THE ZERO MARK. WITH REGARDS TO ANY LINGERING LAKE EFFECT SNOWFALL ACROSS PORTIONS OF THE NORTHWEST INDIANA...CONTINUED BACKING OF THE BOUNDARY LAYER FLOW WILL STEER ANY LINGERING DEVELOPMENT OVER PORTER COUNTY TO THE EAST/NORTHEAST. A RETURN TO MORE ZONAL FLOW WILL BE ON THE SHORT SIDE LATE TUESDAY NIGHT INTO EARLY WEDNESDAY...AS SEVERAL PIECES OF ENERGY TRAVERSE THE CENTRAL CONUS. AFTER ANOTHER NIGHT OF SUBZERO TEMPS TUESDAY NIGHT BACKING FLOW IN RESPONSE TO THESE WAVES WILL FURTHER HELP MODERATE THIS AIR MASS...AS A PERIOD OF WAA IS ANTICIPATED ACROSS THE REGION. THIS WILL HELP SUPPORT HIGH TEMPS NOT ONLY FINALLY ABOVE ZERO...BUT IN THE TEENS AND EVEN LOWER 20S ACROSS THE SOUTHERN CWA WEDNESDAY. A STRONGER AND MORE DEFINED SHORT WAVE TROUGH IS FORECAST TO MOVE EAST THROUGH THE CENTRAL PLAINS WEDNESDAY NIGHT INTO THURSDAY...WITH SURFACE TROUGH/FRONTAL ZONE EXPANDING NORTHEAST TOWARDS THE SOUTHERN CWA. ALTHOUGH SOME WARM ADVECTION PRECIP COULD DEVELOP ACROSS THE SOUTHERN CWA EARLY IN THE EVENING...WOULD EXPECT BETTER PRECIP/SNOW AXIS TO WORK ITS WAY UP TOWARDS THE SOUTHERN CWA DURING THE OVERNIGHT HOURS WEDNESDAY NIGHT. ALTHOUGH SOME SLIGHT DIFFERENCES IN MODEL GUIDANCE REMAINS WITH REGARDS TO THE STRENGTH OF THIS SHORT WAVE TROUGH REMAINS...THERE IS A GENERAL CONSENSUS FOR SNOW TO TO SPREAD INTO PORTIONS OF NORTHEAST/EAST CENTRAL ILLINOIS AND NORTHWEST INDIANA WITH THE BEST FORCING EXPECTED ACROSS THE SOUTHERN CWA. THERE IS THE POTENTIAL FOR CONTINUED DEVELOPMENT INTO PARTS OF THURSDAY...BUT AT THIS TIME EXPECT ANY LINGERING PRECIP TO SHIFT EAST OF THE CWA. GUIDANCE BEGINS TO DIVERGE WITH REGARDS TO THE DETAILS BY LATE IN THE WEEK...BUT THE OVERALL IDEA IS FOR A CONTINUED WARMING TREND. AS THIS TREND CONTINUES TEMPS COULD REACH THE FREEZING MARK AND/OR SURPASS IT BY THE END OF THE PERIOD. ALTHOUGH AS THIS OCCURS...PRECIP TYPE COULD BECOME AN ISSUE AS WELL...AS THERE IS CHANCES FOR RAIN OR SNOW CURRENTLY IN THE FORECAST WHICH WILL NEED TO CONTINUE TO BE MONITORED AS WE APPROACH THIS TIME FRAME. RODRIGUEZ && .AVIATION... //ORD AND MDW CONCERNS...UPDATED 16Z... * SNOW CONTINUES THROUGH THIS AFTN. * GUSTY NORTH WINDS BETWEEN 25-29KT THEN WINDS BACK TO THE NORTHWEST LATE AFTN. * MODERATE SNOW AT TIMES BTWN 16-20Z WITH VSBYS REDUCED TO 3/4SM. * IFR CIGS SLOWLY LIFTING TO MVFR CIGS ARND 03Z. BEACHLER //DISCUSSION...UPDATED 12Z... OVERNIGHT BAND OF LIGHT/OCNL MODERATE SNOW HAS WEAKENED AS EXPECTED EARLY THIS MORNING...WITH A BRIEF LULL ANTICIPATED UNTIL MID-MORNING. ANOTHER WAVE OF MORE ORGANIZED SNOW WILL THEN DEVELOP NORTHEAST FROM MISSOURI AND DOWNSTATE IL DURING THE LATE MORNING AND AFTERNOON HOURS...AS DEEPENING LOW PRESSURE SYSTEM TRACKS THROUGH THE OHIO VALLEY. PERIOD FROM ROUGHLY 16-20/22Z LOOKS TO HAVE THE GREATEST THREAT OF MODERATE SNOW WITH LIFR CONDITIONS INTO ORD/MDW...WITH LOWEST CONDITIONS TO THE SOUTHEAST AND RFD TO THE NORTHWEST LIKELY REMAINING VFR WITH LITTLE SNOW AFTER THIS MORNING. SNOW SHOULD TAPER OFF FROM THE WEST LATE THIS AFTERNOON/EARLY THIS EVENING...WITH IMPROVING VIS/CIG CONDITIONS THIS EVENING LIKELY TO VFR OVERNIGHT. NORTH WINDS WILL INCREASE THROUGH THE DAY AS THE LOW DEEPENS TO OUR SOUTH AND PASSES TO THE EAST. 350-010 DEG GUSTING 20-25 KT THIS MORNING SHOULD BECOME MORE 330-350 DEG 25-30 KT THIS AFTERNOON AND CONTINUING TONIGHT. THIS MAY PRODUCE SOME BLOWING SNOW ISSUES LATE TODAY AND TONIGHT...THOUGH LOW CONFIDENCE IN IMPACTS ON VISIBILITY FOR TAF PURPOSES. WINDS CONTINUE TO GUST 25-30 KT INTO MONDAY...THOUGH EVENTUALLY BECOMING MORE 280-300 DEG BY MONDAY MORNING. RATZER //ORD AND MDW CONFIDENCE...UPDATED 16Z... * MEDIUM-HIGH CONFIDENCE IN SNOW AND ASSOCIATED CIG/VIS TRENDS TODAY. * HIGH CONFIDENCE IN WIND TRENDS. BEACHLER //OUTLOOK FOR ORD/MDW FOR 00Z TUESDAY-12Z SUNDAY...UPDATED 12Z... MONDAY NIGHT...GUSTY WEST WINDS WITH BLOWING SNOW POSSIBLY REDUCING VSBY...OTHERWISE VFR. TUESDAY...VFR. WEDNESDAY AND THURSDAY...CHANCE OF LIGHT SNOW AND IFR. FRIDAY...SLIGHT CHANCE OF LIGHT SNOW AND MVFR. SATURDAY...SLIGHT CHANCE OF LIGHT RAIN/SNOW AND MVFR. RATZER && .MARINE... 236 AM CST MAIN MARINE CONCERNS ARE A PERIOD OF NORTH-NORTHWEST GALE FORCE WINDS ACROSS MAINLY THE SOUTHERN HALF OF LAKE MICHIGAN TODAY INTO EARLY TUESDAY...ALONG WITH HEAVY FREEZING SPRAY POTENTIAL WITH BITTERLY COLD ARCTIC AIR SPREADING ACROSS THE REGION. A COLD FRONT WHICH PUSHED SOUTHEAST OF THE LAKE LATE SATURDAY WILL BE THE FOCUS FOR AN AREA OF LOW PRESSURE WHICH WILL LIFT NORTHEAST THROUGH THE OHIO VALLEY TODAY...AND ACROSS THE EASTERN LAKES INTO QUEBEC TONIGHT AND EARLY MONDAY MORNING. THE COMBINATION OF THE DEEPENING LOW PRESSURE SYSTEM AND STRONG CANADIAN HIGH PRESSURE SPREADING SOUTHEAST ACROSS THE PLAINS WILL RESULT IN A TIGHTENING SURFACE PRESSURE GRADIENT ACROSS THE WESTERN LAKES...WHICH WILL PROVIDE STRONG NORTH-NORTHWEST WINDS ACROSS LAKE MICHIGAN. FORECAST SOUNDINGS INDICATE GALES IN THE 35-40 KT RANGE ARE HIGHLY LIKELY ACROSS THE SOUTHERN PORTION OF THE LAKE BY MID/LATE THIS AFTERNOON AND WILL GRADUALLY BECOME WEST-NORTHWEST THROUGH MONDAY AND MONDAY NIGHT BEFORE GRADUALLY DIMINISHING BELOW GALE FORCE EARLY TUESDAY MORNING. A BITTERLY COLD ARCTIC AIR MASS WAS SPREADING SOUTHEAST ACROSS THE PLAINS AND UPPER MIDWEST...WHICH WILL COMBINE WITH HIGH WINDS AND WAVES TO PRODUCE HEAVY FREEZING SPRAY ON VESSELS WHICH VENTURE OUT ON THE LAKE DURING THE EARLY PORTION OF THIS WEEK. THUS GALE AND HEAVY FREEZING SPRAY WARNINGS ARE IN EFFECT THROUGH EARLY TUESDAY. HIGH PRESSURE RIDGING WILL EVENTUALLY PUSH INTO THE WESTERN GREAT LAKES REGION MID-WEEK...ALLOWING WINDS TO DIMINISH MORE QUICKLY LATE TUESDAY NIGHT THROUGH THURSDAY. MODERATING TEMPERATURES ALONG WITH LIGHTER WINDS SHOULD EASE FREEZING SPRAY CONCERNS BY MID-WEEK AS WELL. FOR THE ILLINOIS AND INDIANA NEARSHORE WATERS...GALE AND FREEZING SPRAY WARNINGS INCLUDE INDIANA WATERS WITH NORTHWEST FETCH OFF OPEN WATERS. WINDS ALONG THE ILLINOIS SHORE LOOK TO BE MARGINAL WITH RESPECT TO SOLID GALES...WITH GUSTS NEAR BUT PERHAPS INFREQUENTLY TOPPING 34 KT. WILL GO AHEAD AND UPGRADE THE CURRENT GALE WATCH TO A WARNING FOR THE IL SHORE...BUT ONLY THROUGH 18Z MONDAY BY WHICH TIME FLOW BACKS MORE WESTERLY AND SPEEDS DECREASE A LITTLE THROUGH THE MIXED LAYER. RATZER && .LOT WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING...ILZ006-ILZ010-ILZ011-ILZ012-ILZ013-ILZ014- ILZ019-ILZ020-ILZ021-ILZ022 UNTIL 6 PM SUNDAY. WIND CHILL WARNING...ILZ003-ILZ004-ILZ005-ILZ006-ILZ008-ILZ010- ILZ011-ILZ012-ILZ013-ILZ014-ILZ019-ILZ020-ILZ021-ILZ022...6 PM SUNDAY TO NOON TUESDAY. WINTER STORM WARNING...ILZ023-ILZ032-ILZ033-ILZ039 UNTIL MIDNIGHT MONDAY. WIND CHILL WARNING...ILZ023-ILZ032-ILZ033-ILZ039...MIDNIGHT MONDAY TO NOON TUESDAY. IN...WIND CHILL WARNING...INZ001-INZ002-INZ010-INZ011- INZ019...MIDNIGHT MONDAY TO NOON TUESDAY. WINTER STORM WARNING...INZ001-INZ002-INZ010-INZ011-INZ019 UNTIL MIDNIGHT MONDAY. LM...GALE WARNING...LMZ080-LMZ669-LMZ671-LMZ673-LMZ675-LMZ743-LMZ744- LMZ745-LMZ777-LMZ779-LMZ870-LMZ872-LMZ874-LMZ876-LMZ878...3 PM SUNDAY TO 4 AM TUESDAY. HEAVY FREEZING SPRAY WARNING...LMZ080-LMZ261-LMZ362-LMZ364- LMZ366-LMZ563-LMZ565-LMZ567-LMZ669-LMZ671-LMZ673-LMZ675- LMZ743-LMZ744-LMZ745-LMZ777-LMZ779-LMZ868-LMZ870-LMZ872- LMZ874-LMZ876-LMZ878...3 PM SUNDAY TO 4 AM TUESDAY. GALE WARNING...LMZ740-LMZ741-LMZ742...3 PM SUNDAY TO NOON MONDAY. SMALL CRAFT ADVISORY...NEARSHORE WATERS UNTIL 3 PM SUNDAY. && $$ VISIT US AT HTTP://WEATHER.GOV/CHICAGO (ALL LOWERCASE) FOLLOW US ON FACEBOOK...TWITTER...AND YOUTUBE AT: WWW.FACEBOOK.COM/US.NATIONALWEATHERSERVICE.CHICAGO.GOV WWW.TWITTER.COM/NWSCHICAGO WWW.YOUTUBE.COM/NWSCHICAGO
Area Forecast Discussion National Weather Service Lincoln IL 1059 AM CST Sun Jan 5 2014 .DISCUSSION... ISSUED 1058 AM CST Sun Jan 5 2014 Main complication with the event thus far has been the mixed precipitation across the southeast CWA. Temps still hanging in the lower 30s across much of east central and southeast Illinois. Enhanced reflectivities on radar showing the mixed precip continuing from around Carbondale northeast through Lawrenceville, having switched over to snow elsewhere south of I-70. Main surface low still back over the western tip of Kentucky and will track northeast along the Ohio River through midday. RAP sounding from Lawrenceville shows the mixture may continue into early afternoon. Have toned down snow totals across the extreme southeast due to this mixture. With the warmer temperatures in the east, the snow has been wetter than first expected. While winds may be strong enough to reach blizzard criteria this afternoon, the snow may not blow around as severely. Will keep the current headlines as-is and continue to monitor. Geelhart && .AVIATION... ISSUED 1058 AM CST Sun Jan 5 2014 LIFR to VLIFR conditions will continue through the afternoon. Some improvement being noted northwest of KPIA along the back edge of the snow shield, but areas of blowing snow will result in MVFR visibilities at times as the snow ends. Think that KCMI/KBMI/KDEC will see visibilities of 1/2SM or less for several more hours, as a surface low moves up the lower Ohio River and enhances the bands of snow to its northwest. Northerly winds will slowly trend to the northwest. Gusts of 25-35 knots will persist through the early evening hours. Increases in the ceilings will take place early in the evening as skies become clear. Geelhart && .PREV DISCUSSION... ISSUED 344 AM CST Sun Jan 5 2014 Ongoing winter storm in progress with the first round of precip along a frontogenetic band across the NW. Starting to fill in a bit to the east of Interstate 55...and struggling with precip type as cold air is slow moving to the southeast. Models slowing down appreciably with the forward progression of the developing sfc low through midday. Some minor adjustments to the snowfall and adding in a bit of a mix for the early morning in the extreme SE where cold air is slower to approach. Plenty of moisture still there to work with. Forecast into the extended has another system for midweek with some more snow in store...but that is where extended models diverge with very different ideas into Day 7. Adjustments to the short term forecast...ALLBLEND nearly left alone for the extended. SHORT TERM...Today through tomorrow... Snow continuing to spread as the cold air filters into the SE and the changeover to snow dominates. S of Interstate 55 will see a bit of wintry mix this morning until mid morning. This will change the amount of snow for the SE...but only for the morning...as the bulk of the storm will be arriving for mid morning through the end of the day. Delay in the progression of the sfc low...with the RUC/RAP slowing even more than the HRRR...moving through the Ohio River Valley this afternoon. Back edge of the heaviest precip a bit of a problem, varying a bit from model to model with introduction of drier air on the NWrn edge...but 3 to 5 inches already NW of the Illinois River Valley resulting in an upgrade to a Winter Storm Warning. Snow totals overall not changing much with regards to entire event. Brutally cold air moving in on the back side of this system. Cold air already settling into southern Canada and will be sinking in behind the exiting storm. In combination with winds in the 25 to 30 mph range...wind chills will drop to a very dangerous -30 to -40 from tonight...through Tuesday morning. Wind chill warning remains. Those same winds will cause problems with blowing and drifting snow well after the end of the snowfall tonight. LONG TERM...Tuesday through Saturday... Tues and Tues night highs and lows both in the single digits as the region begins a slow warm up. SWrly flow aloft as another trof digs into the desert SW and southerly winds at sfc usher warmer temps in for Wednesday with highs in the 20s. Another system ejecting out of the SW for Wed night/Thursday. Best chances for precip to the SE, similar to current storm...but far too early for details. Climo has major impact to the highs and lows beyond that point and the ECMWF and the GFS diverge majorly. Very low confidence in the extended. HJS && .ILX WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING until Midnight CST tonight FOR ILZ027>031- 036>038-040>057-061>063-066>068-071>073. WIND CHILL WARNING from Midnight tonight to Noon CST Tuesday FOR ILZ027>031-036>038-040>057-061>063-066>068-071>073. && $$
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
308 PM EST SUN JAN 5 2014 .UPDATE... LONG TERM SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 319 AM EST SUN JAN 5 2014 A STORM SYSTEM IS EXPECTED TO BRING A SIGNIFICANT WINTER STORM TO THE AREA TODAY AND TONIGHT...FOLLOWED BY VERY COLD AIR EARLY NEXT WEEK IN THE WAKE OF THIS STORM. ADDITIONAL FRONTAL SYSTEM MAY AFFECT THE AREA AROUND THE MIDDLE OF THE WEEK AND OVER NEXT WEEKEND. && .NEAR TERM /REST OF TODAY AND TONIGHT/... ISSUED AT 943 AM EST SUN JAN 5 2014 CURRENT FORECAST IS ON TRACK. PRECIPITATION HAS OVERSPREAD THE AREA...WITH MODERATE SNOW ACROSS NORTHWEST 2/3 OF CENTRAL INDIANA. ACROSS THE REMAINDER OF THE AREA...A MIX OF RAIN AND SNOW OR JUST RAIN CONTINUES. DUAL-POL RADAR SHOWING MIXED PRECIPITATION IS MOVING NORTH AS EXPECTED. RAP TRIES TO BRING MIX AS FAR NORTH AS INDIANAPOLIS BUT LATEST NAM12 KEEPS IT JUST SOUTHEAST OF INDY. BASED ON EXPECTED PATH OF LOW AND CURRENT TRENDS... LEFT FORECAST AS IS WITH MIX COMING AS FAR NORTH AS SHELBYVILLE/RUSHVILLE. WILL MONITOR CLOSELY. PREVIOUS DISCUSSION FOLLOWS... THINGS SEEM TO BE EVOLVING SLOWER THAN EXPECTED...BUT MODEL DATA SUGGEST THE MAIN THEME REMAINS THE SAME. MODELS IN RATHER GOOD AGREEMENT NOW WITH RESPECT TO THE DEVELOPING SURFACE LOW...TRACKING IT NEAR OF JUST SOUTH OF THE OHIO RIVER THIS AFTERNOON AND EVENING. NOT TOO MUCH GOING ON AT THIS TIME...HOWEVER THE MAIN LIFT FROM THIS STORM IS EXPECTED TO BEGIN MOVING INTO THE AREA AFTER SUNRISE...SO EXPECTING PRECIPITATION TO INCREASE IN INTENSITY/COVERAGE BY THAT TIME. THE STRONGEST LIFT/HEAVIEST PRECIPITATION LOOKS TO PASS OVER THE AREA FROM ABOUT MIDDAY THROUGH THE AFTERNOON HOURS. SOME LINGERING WARM AIR OVER THE SOUTH/SOUTHEAST ZONES SHOULD RESULT IN MORE OF A MIX INTO THE AFTERNOON HOURS BEFORE THE ATMOSPHERIC COLUMN COOLS. ELSEWHERE...PRECIPITATION TYPE EXPECTED TO REMAIN SNOW. MODEL DATA SUGGEST DEFORMATION ZONE WILL STILL BE OVER THE WESTERN ZONES BY EVENING...SO THINK LIGHTER SNOWFALL WILL CONTINUE OVER THE AREA THROUGH ABOUT MIDNIGHT BEFORE TAPERING OFF TO SNOW SHOWERS AND FLURRIES. WINDS EXPECTED TO PICK UP TOWARDS/AFTER SUNSET TONIGHT WITH GUST TO AROUND 40 MPH POSSIBLE. THIS WILL CAUSE CONSIDERABLE BLOWING AND DRIFTING SNOW. MAY FLIRT WITH BLIZZARD CRITERIA FOR A PERIOD THIS EVENING...BUT WITH THE HEAVIER SNOW DIMINISHING BY THAT TIME...MAY BE HARD TO REACH VISIBILITY CRITERIA. THIS WILL BE SOMETHING THAT WILL NEED TO BE WATCHED. GIVEN A SURFACE LOW TRACK ALONG THE OHIO RIVER AND LOCATION OF DEFORMATION ZONE...STILL APPEARS THE HIGHEST STORM TOTALS WILL BE LOCATED OVER THE NORTHWEST HALF OF THE FORECAST AREA...WITH LESSER TOTALS FARTHER SOUTHEAST DUE TO MIXING ISSUES AND BEING LOCATED FARTHER AWAY FROM THE DEFORMATION ZONE. MODEL GUIDANCE SUGGESTS POTENTIAL STORM TOTALS FROM AROUND 5 INCHES OVER THE FAR SOUTHEAST TO ABOUT 10 TO 14 INCHES OVER THE NORTHWEST HALF OF THE AREA. WILL HOLD ONTO THE WINTER STORM WARNING AS IS FOR NOW...ALTHOUGH IT DOES APPEAR CONDITIONS WON/T BEGIN TO DETERIORATE UNTIL AFTER SUNRISE. DUE TO THE SLOWER EVOLUTION OF THE STORM...MAY NEED TO EXTEND THE WARNING LATER IN TIME AS WELL. WILL ALSO BE ISSUING A WIND CHILL WARNING STARTING LATE TONIGHT AND LASTING THROUGH TUESDAY WITH WIND CHILLS EXPECTED TO EXCEED WARNING CRITERIA THROUGHOUT THOSE TIMES. EXPECTING TEMPERATURES TO HOLD ABOUT STEADY UNTIL PRECIPITATION BEGINS...THEN SLOWLY FALL OFF DURING THE AFTERNOON. THE SLOWER EVOLUTION OF THE STORM SUGGESTS TEMPERATURES PROBABLY WON/T REALLY START FALLING ON UNTIL AFTER SUNSET. BASED ON LOW LEVEL THICKNESSES...THE GFS MOS LOWS TONIGHT LOOK TOO COLD. WILL BUMP THEM UP ABOUT 3-5 DEGREES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... ISSUED AT 319 AM EST SUN JAN 5 2014 DEEP COLD UPPER LOW OVER THE GREAT LAKES ON MONDAY EXPECTED TO REMAIN PROGRESSIVE...SO VERY COLD TEMPERATURES SHOULD GRADUALLY MODERATE DURING THE PERIOD AS HEIGHTS SLOWLY RISE. OTHER THAN SOME FLURRIES ON MONDAY DUE TO VERY STEEP LOW LEVEL LAPSE RATES...THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE MOVES THROUGH. LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS HIGHS AND LOWS MONDAY AND MONDAY NIGHT LOOK A LITTLE TOO COLD. WILL RAISE THE GUIDANCE SEVERAL DEGREES IN THOSE PERIODS. HIGHS BY TUESDAY LOOK BETTER...BUT MAY STILL BE A LITTLE COLD. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... ISSUED AT 308 PM EST SUN JAN 5 2014 A ZONAL UPPER FLOW PREDOMINATES IN THE LONG TERM AND TEMPERATURES WILL MODERATE THROUGH THE PERIOD AND WITH ABOVE NORMAL TEMPERATURES BY THE WEEKEND. THERE ARE A COUPLE OF WEAK SYSTEM WHICH WILL AFFECT US WITH ONE MOVING THROUGH AROUND WEDNESDAY NIGHT/THURSDAY AND ANOTHER EARLY SATURDAY FOLLOWED BY ANOTHER TOWARDS THE END OF DAY 7. THE WEDNESDAY NIGHT/THURSDAY SYSTEM MAY GENERATE LIGHT TO MODERATE SNOW ACCUMULATIONS...BUT BY THE WEEKEND IT WILL BE WARMUP FOR MOST OF THE PRECIPITATION TO LIQUID. OVERALL THE ALLBLEND ON TEMPERATURES SEEM REASONABLE AND ONLY MINOR CHANGES MADE. HIGHS WILL BE IN THE 20S WEDNESDAY WARMING TO THE UPPER 30S TO LOWER 40S OVER THE WEEKEND. && .AVIATION /DISCUSSION FOR THE 051800Z TAF ISSUANCE/... ISSUED AT 1208 PM EDT SUN JAN 5 2014 LIFR CEILINGS AND SNOW WILL BE THE RULE THIS AFTERNOON INTO THIS EVENING WITH INCREASING WINDS BY EVENING. THIS WILL BE FOLLOWED BY A GRADUAL IMPROVEMENT LATE TONIGHT. LOW PRESSURE OVER WESTERN KENTUCKY WILL TRACK NORTHEAST ACROSS THE OHIO VALLEY THIS AFTERNOON AND INTO SOUTHERN OHIO BY THIS EVENING AND TO THE EASTERN GREAT LAKES BY 06Z. THIS SYSTEM WILL GENERATE SNOW OVER MUCH OF THE AREA. HOWEVER KBMG MAY BE WARM ENOUGH TO SEE A WINTRY MIX FOR THE FIRST FEW HOURS BEFORE CHANGING TO SNOW. AS THE SURFACE LOW PULLS TO OUR EAST...A STRONG PRESSURE GRADIENT WILL SET UP ACROSS THE AREA AND SURFACE WINDS WILL INCREASE TO 23 KNOTS WITH GUSTS TO 30 TO 35 KNOTS THIS EVENING CAUSING CONSIDERABLE BLOWING AND DRIFTING OF SNOW. AS SNOW DIMINISHES LATER THIS EVENING AS LOW PRESSURE MOVES TO THE NORTHEAST CEILINGS AND VISIBILITIES WILL BEGIN A VERY SLOW IMPROVEMENT REACHING A COUPLE OF MILES VISIBILITY AND MVFR CEILINGS AFTER MIDNIGHT. ON MONDAY...EXPECT ONLY SCATTERED FLURRIES AS DRIER AIR MOVES IN...BUT WITH BLOWING SNOW MAY KEEP VISIBILITIES MVFR. WINDS MONDAY WILL BE WEST 15 TO 25 KNOTS. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 AM EST MONDAY FOR INZ021-028>031- 035>049-051>057-060>065-067>072. WIND CHILL WARNING FROM 1 AM MONDAY TO 7 PM EST TUESDAY FOR INZ021-028>031-035>049-051>057-060>065-067>072. && SYNOPSIS...JAS NEAR TERM...JAS/50 SHORT TERM...JAS LONG TERM....JH AVIATION...JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS INDIANAPOLIS IN
1208 PM EST SUN JAN 5 2014 .UPDATE... AVIATION SECTION HAS BEEN UPDATED BELOW. && .SYNOPSIS... ISSUED AT 319 AM EST SUN JAN 5 2014 A STORM SYSTEM IS EXPECTED TO BRING A SIGNIFICANT WINTER STORM TO THE AREA TODAY AND TONIGHT...FOLLOWED BY VERY COLD AIR EARLY NEXT WEEK IN THE WAKE OF THIS STORM. ADDITIONAL FRONTAL SYSTEM MAY AFFECT THE AREA AROUND THE MIDDLE OF THE WEEK AND OVER NEXT WEEKEND. && .NEAR TERM /REST OF TODAY AND TONIGHT/... ISSUED AT 943 AM EST SUN JAN 5 2014 CURRENT FORECAST IS ON TRACK. PRECIPITATION HAS OVERSPREAD THE AREA...WITH MODERATE SNOW ACROSS NORTHWEST 2/3 OF CENTRAL INDIANA. ACROSS THE REMAINDER OF THE AREA...A MIX OF RAIN AND SNOW OR JUST RAIN CONTINUES. DUAL-POL RADAR SHOWING MIXED PRECIPITATION IS MOVING NORTH AS EXPECTED. RAP TRIES TO BRING MIX AS FAR NORTH AS INDIANAPOLIS BUT LATEST NAM12 KEEPS IT JUST SOUTHEAST OF INDY. BASED ON EXPECTED PATH OF LOW AND CURRENT TRENDS... LEFT FORECAST AS IS WITH MIX COMING AS FAR NORTH AS SHELBYVILLE/RUSHVILLE. WILL MONITOR CLOSELY. PREVIOUS DISCUSSION FOLLOWS... THINGS SEEM TO BE EVOLVING SLOWER THAN EXPECTED...BUT MODEL DATA SUGGEST THE MAIN THEME REMAINS THE SAME. MODELS IN RATHER GOOD AGREEMENT NOW WITH RESPECT TO THE DEVELOPING SURFACE LOW...TRACKING IT NEAR OF JUST SOUTH OF THE OHIO RIVER THIS AFTERNOON AND EVENING. NOT TOO MUCH GOING ON AT THIS TIME...HOWEVER THE MAIN LIFT FROM THIS STORM IS EXPECTED TO BEGIN MOVING INTO THE AREA AFTER SUNRISE...SO EXPECTING PRECIPITATION TO INCREASE IN INTENSITY/COVERAGE BY THAT TIME. THE STRONGEST LIFT/HEAVIEST PRECIPITATION LOOKS TO PASS OVER THE AREA FROM ABOUT MIDDAY THROUGH THE AFTERNOON HOURS. SOME LINGERING WARM AIR OVER THE SOUTH/SOUTHEAST ZONES SHOULD RESULT IN MORE OF A MIX INTO THE AFTERNOON HOURS BEFORE THE ATMOSPHERIC COLUMN COOLS. ELSEWHERE...PRECIPITATION TYPE EXPECTED TO REMAIN SNOW. MODEL DATA SUGGEST DEFORMATION ZONE WILL STILL BE OVER THE WESTERN ZONES BY EVENING...SO THINK LIGHTER SNOWFALL WILL CONTINUE OVER THE AREA THROUGH ABOUT MIDNIGHT BEFORE TAPERING OFF TO SNOW SHOWERS AND FLURRIES. WINDS EXPECTED TO PICK UP TOWARDS/AFTER SUNSET TONIGHT WITH GUST TO AROUND 40 MPH POSSIBLE. THIS WILL CAUSE CONSIDERABLE BLOWING AND DRIFTING SNOW. MAY FLIRT WITH BLIZZARD CRITERIA FOR A PERIOD THIS EVENING...BUT WITH THE HEAVIER SNOW DIMINISHING BY THAT TIME...MAY BE HARD TO REACH VISIBILITY CRITERIA. THIS WILL BE SOMETHING THAT WILL NEED TO BE WATCHED. GIVEN A SURFACE LOW TRACK ALONG THE OHIO RIVER AND LOCATION OF DEFORMATION ZONE...STILL APPEARS THE HIGHEST STORM TOTALS WILL BE LOCATED OVER THE NORTHWEST HALF OF THE FORECAST AREA...WITH LESSER TOTALS FARTHER SOUTHEAST DUE TO MIXING ISSUES AND BEING LOCATED FARTHER AWAY FROM THE DEFORMATION ZONE. MODEL GUIDANCE SUGGESTS POTENTIAL STORM TOTALS FROM AROUND 5 INCHES OVER THE FAR SOUTHEAST TO ABOUT 10 TO 14 INCHES OVER THE NORTHWEST HALF OF THE AREA. WILL HOLD ONTO THE WINTER STORM WARNING AS IS FOR NOW...ALTHOUGH IT DOES APPEAR CONDITIONS WON/T BEGIN TO DETERIORATE UNTIL AFTER SUNRISE. DUE TO THE SLOWER EVOLUTION OF THE STORM...MAY NEED TO EXTEND THE WARNING LATER IN TIME AS WELL. WILL ALSO BE ISSUING A WIND CHILL WARNING STARTING LATE TONIGHT AND LASTING THROUGH TUESDAY WITH WIND CHILLS EXPECTED TO EXCEED WARNING CRITERIA THROUGHOUT THOSE TIMES. EXPECTING TEMPERATURES TO HOLD ABOUT STEADY UNTIL PRECIPITATION BEGINS...THEN SLOWLY FALL OFF DURING THE AFTERNOON. THE SLOWER EVOLUTION OF THE STORM SUGGESTS TEMPERATURES PROBABLY WON/T REALLY START FALLING ON UNTIL AFTER SUNSET. BASED ON LOW LEVEL THICKNESSES...THE GFS MOS LOWS TONIGHT LOOK TOO COLD. WILL BUMP THEM UP ABOUT 3-5 DEGREES. && .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... ISSUED AT 319 AM EST SUN JAN 5 2014 DEEP COLD UPPER LOW OVER THE GREAT LAKES ON MONDAY EXPECTED TO REMAIN PROGRESSIVE...SO VERY COLD TEMPERATURES SHOULD GRADUALLY MODERATE DURING THE PERIOD AS HEIGHTS SLOWLY RISE. OTHER THAN SOME FLURRIES ON MONDAY DUE TO VERY STEEP LOW LEVEL LAPSE RATES...THE SHORT TERM SHOULD BE DRY AS HIGH PRESSURE MOVES THROUGH. LOW LEVEL THICKNESS PROGS SUGGEST THE GFS MOS HIGHS AND LOWS MONDAY AND MONDAY NIGHT LOOK A LITTLE TOO COLD. WILL RAISE THE GUIDANCE SEVERAL DEGREES IN THOSE PERIODS. HIGHS BY TUESDAY LOOK BETTER...BUT MAY STILL BE A LITTLE COLD. && .LONG TERM /WEDNESDAY THROUGH SUNDAY/... ISSUED AT 334 AM EST SUN JAN 5 2014 ACTIVE PATTERN CONTINUES THROUGH THE PERIOD...WITH YET ANOTHER CHANCE FOR ACCUMULATING SNOW BEGINNING LATE WEDNESDAY AS AN UPPER LEVEL WAVE DROPS SOUTHEAST OUT OF THE NORTHERN PLAINS AND INTERACTING WITH A SURFACE TROUGH AND GULF MOISTURE LIFTING NORTH INTO THE REGION. THIS FEATURE WILL LIFT SLOWLY THROUGH THE OHIO VALLEY WITH SNOW LIKELY TO FALL WEDNESDAY NIGHT AND THURSDAY... POSSIBLY CONTINUING INTO THURSDAY NIGHT. STILL A BIT PREMATURE TO CONSIDER SPECIFIC ACCUMS AT THIS POINT BUT IT DOES APPEAR THE POTENTIAL WILL EXIST FOR A FEW INCHES OF SNOW AT THE VERY LEAST. UPPER LEVEL FLOW WILL TRANSITION FROM QUASI-ZONAL TO A MOIST SOUTHWEST FLOW BY FRIDAY AS AN UPPER LEVEL LOW DEVELOPS OVER NORTHERN MEXICO. ANOTHER STORM SYSTEM SET TO DEVELOP AND EXPAND TOWARDS THE OHIO/TENNESSEE VALLEYS OVER THE WEEKEND AS THE UPPER LOW EJECTS INTO TEXAS BY SUNDAY. APPEARS ENOUGH WARM AIR WITHIN THE LOWER LEVELS WILL ADVECT NORTH TO PRESENT A WINTRY PRECIP MIX OR EVEN A PERIOD WITH RAIN AS THE PREDOMINANT PRECIP TYPE. HIGHS SHOULD WARM BACK INTO THE 30S TO LOWER 40S BY SATURDAY AND SUNDAY...LIKELY TO BE A WELCOME CHANGE FROM THE BITTERLY COLD TEMPS TO COME OVER THE NEXT FEW DAYS. && .AVIATION /DISCUSSION FOR THE 051800Z TAF ISSUANCE/... ISSUED AT 1208 PM EDT SUN JAN 5 2014 LIFR CEILINGS AND SNOW WILL BE THE RULE THIS AFTERNOON INTO THIS EVENING WITH INCREASING WINDS BY EVENING. THIS WILL BE FOLLOWED BY A GRADUAL IMPROVEMENT LATE TONIGHT. LOW PRESSURE OVER WESTERN KENTUCKY WILL TRACK NORTHEAST ACROSS THE OHIO VALLEY THIS AFTERNOON AND INTO SOUTHERN OHIO BY THIS EVENING AND TO THE EASTERN GREAT LAKES BY 06Z. THIS SYSTEM WILL GENERATE SNOW OVER MUCH OF THE AREA. HOWEVER KBMG MAY BE WARM ENOUGH TO SEE A WINTRY MIX FOR THE FIRST FEW HOURS BEFORE CHANGING TO SNOW. AS THE SURFACE LOW PULLS TO OUR EAST...A STRONG PRESSURE GRADIENT WILL SET UP ACROSS THE AREA AND SURFACE WINDS WILL INCREASE TO 23 KNOTS WITH GUSTS TO 30 TO 35 KNOTS THIS EVENING CAUSING CONSIDERABLE BLOWING AND DRIFTING OF SNOW. AS SNOW DIMINISHES LATER THIS EVENING AS LOW PRESSURE MOVES TO THE NORTHEAST CEILINGS AND VISIBILITIES WILL BEGIN A VERY SLOW IMPROVEMENT REACHING A COUPLE OF MILES VISIBILITY AND MVFR CEILINGS AFTER MIDNIGHT. ON MONDAY...EXPECT ONLY SCATTERED FLURRIES AS DRIER AIR MOVES IN...BUT WITH BLOWING SNOW MAY KEEP VISIBILITIES MVFR. WINDS MONDAY WILL BE WEST 15 TO 25 KNOTS. && .IND WATCHES/WARNINGS/ADVISORIES... WINTER STORM WARNING UNTIL 1 AM EST MONDAY FOR INZ021-028>031- 035>049-051>057-060>065-067>072. WIND CHILL WARNING FROM 1 AM MONDAY TO 7 PM EST TUESDAY FOR INZ021-028>031-035>049-051>057-060>065-067>072. && $$ SYNOPSIS...JAS NEAR TERM...JAS/50 SHORT TERM...JAS LONG TERM....RYAN AVIATION...JH VISIT US AT HTTP://WWW.WEATHER.GOV/IND FOLLOW US ON TWITTER AND YOUTUBE AT: WWW.TWITTER.COM/NWSINDIANAPOLIS WWW.YOUTUBE.COM/NWSINDIANAPOLIS
AREA FORECAST DISCUSSION
NWS PADUCAH KY
323 PM CST Sun Jan 5 2014 .SHORT TERM...(This Evening through Monday) ISSUED AT 323 PM CST SUN JAN 5 2014 Current radar mosiac indicates temporary weakening of pcpn echoes west of the MS river, however some enhancement is also indicated over sern MO/swrn IL associated with the exit region of an upper level jet. Meanwhile, the nwrn half of the region is under very rapid cold air advection behind a ewd-departing sfc low, and these very raw conditions will rapidly sweep across the rest of the region during the late afternoon. Flash freezing of water on roads is expected. Dual Pol correlation coefficient from KVWX radar was clearly showing the rain/snow line beginning to accelerate ewd. Any intervals of freezing rain or sleet are expected to be even briefer in duration than they have been up to now. The HRRR model suggests that the aforementioned enhanced area of snowfall over sern MO/swrn IL will fill in over most of the region late this afternoon, except west of Poplar Bluff MO, where snowfall will taper off rapidly to flurries by sunset. After sunset, little measurable snowfall is forecast, but lingering moisture in the new arctic air mass will probably produce flurries across the entire region into part of the overnight hours. A secondary mid level shrtwv will produce clouds and may produce more flurries during the day Mon. We will flirt with record lows tonight and Mon night and will shatter minimum highs for Mon. Dangerous wind chill readings early Mon morning will range from -20 south to -30 north. The brisk breeze will slowly decrease during the day. The sun will return Tue, along with "warmer" temps in the teens. .LONG TERM...(Monday Night through Sunday) ISSUED AT 323 PM CST SUN JAN 5 2014 Extended models are in general agreement but there are always issues in the details. Early Wednesday there is a broad trough over the eastern US with a more zonal flow over the western US. By Thursday two main troughs can be seen to our west. One over KS and OK with another off the NW coast of the US. The first impulse is slow to get here as the overall pattern changes to a trough in the west and more zonal flow in the east. But we will have overrunning precipitation both Wednesday and Thursday. By 00Z Saturday, the GFS, GEM, and ECMWF want to carve out an upper level low over the southwest US or Mexico. After that the speed and intensity of the wave is in question as it moves toward us. The initial precipitation type will be snow or freezing rain with the GFS being the warmer model aloft and hence the chance of freezing rain. Snowfall accumulations will be light but will have to be monitored. Held off on any ice accumulation until the models have a better handle on the situation. The good news is that by Friday warm air has taken over the entire CWA and expect liquid precipitation over the region through the weekend. && .AVIATION... ISSUED AT 323 PM CST SUN JAN 5 2014 Location of surface low has required adjustments to changeover time for all sites. Heaviest precip is now just northwest of KEVV with a dry slot over parts of SEMO. Changeover to snow has occurred at KCGI, and KPAH. Expect changeover at KEVV around 21 UTC and KOWB shortly thereafter. Precip should exit the area late this afternoon into early evening. && .PAH WATCHES/WARNINGS/ADVISORIES... IL...WINTER STORM WARNING until 6 PM CST this evening FOR ILZ075>078- 080>089-092-093. WIND CHILL ADVISORY from 6 PM this evening to 9 AM CST Tuesday FOR ILZ084>094. WIND CHILL WARNING from 6 PM this evening to 9 AM CST Tuesday FOR ILZ075>078-080>083. WINTER WEATHER ADVISORY until 6 PM CST this evening FOR ILZ090- 091-094. MO...WINTER STORM WARNING until 6 PM CST this evening FOR MOZ076-086- 087-100-107>111. WIND CHILL ADVISORY from 6 PM this evening to 9 AM CST Tuesday FOR MOZ076-086-087-100-107>112-114. WINTER WEATHER ADVISORY until 6 PM CST this evening FOR MOZ112- 114. IN...WINTER STORM WARNING until 6 PM CST this evening FOR INZ081-082- 085-086. WIND CHILL WARNING from 6 PM this evening to 9 AM CST Tuesday FOR INZ081-082-085>088. WINTER WEATHER ADVISORY until 6 PM CST this evening FOR INZ087- 088. KY...WIND CHILL ADVISORY from 6 PM this evening to 9 AM CST Tuesday FOR KYZ001>022. WINTER WEATHER ADVISORY until 6 PM CST this evening FOR KYZ001>022. && $$ SHORT TERM...DB LONG TERM...PS AVIATION...PS
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1223 PM EST Sun Jan 5 2014 ...Updated Aviation Discussion... ...Forecast Update... Updated at 1150 AM EST Sun Jan 5 2014 Precipitation continues to develop out over western KY this morning. Strong surge of warm air advection is taking place as temperatures are nearing 50 degrees down along the KY/TN border region. Probably will need to adjust our max temperatures for today down that way a little bit. Latest 12Z data generally has trended close to the previous 00Z and 06Z runs that were warmer and a little slower with the storm`s progression through the Ohio Valley. With that said, we feel that the current snowfall totals over our warning area (southern Indiana) is a bit too aggressive at this time. After careful coordination with ILN/IND/PAH we will be downgrading the warning across southern Indiana to a Winter Weather Advisory. We will also be adjusting the start time of the advisory products to better align with the thinking below. The Winter Weather Advisories will also be extended in time to go throughout the night due to the anticipated high impacts across the region. Current prognostic data fields and thermal analysis continues to show that we will see rain fall across the region this afternoon. As the surface low pressure system moves through western KY and into Ohio, a strong Arctic front will push in from the west. This front will usher in much colder air into the region. It appears that we will start to see a change over in our western sections around 4-5 PM EST...with a change over occurring in the I-65 corridor between 6-8 PM and in the I-75 corridor in the 9-11 PM time frame. Not really incorporating much of the NCEP model timing here but this is more of a blend of our in house high resolution WRF and the experimental HRRR which appears to have a good handle on the cold surge coming in from the west. We still expect to see a band of moderate to heavy snow come in behind the front. However, this will not last long as it will quickly move through the region. The models along with upstream satellite and observations show a dry slot developing across eastern OK and west-central AR which will likely pivot into our region late tonight. So while we will get in on the snow, it does not appear that it will hang around all that much. Though the snowfall is really the secondary story of this system. Of more concern will be the tumble in temperatures. We will see temperatures go from the 30s this evening down to near zero by dawn. This will lead to a quick freeze up of moisture on roads/objects. This combined with the snow will make travel treacherous tonight. With regards to snowfall accumulations, we are going to trim back amounts slightly across southern IN where we believe 2-4 inches is still likely. The 4 inch amounts would be most likely across our far northern portions of Dubois, Orange, Washington, Scott, and Jefferson counties in southern Indiana. Elsewhere across KY a general 1-3 inches will be possible. This will be a non-uniform snow...so some areas will pick up an inch here while other areas may pick up slightly more. We are currently in the production of updated products and those should be ready in the next 30-45 minutes. Updated web graphics and briefing slides will also be available early this afternoon. Additional meteorological details for later tonight and Monday will be forthcoming in the standard afternoon discussion which will be available by mid-afternoon. Update issued at 830 AM EST Sun Jan 5 2014 Early morning radar mosaics show our winter storm taking aim on the region. Rain showers have broken out across the region...mainly west of I-65 with more extensive precipitation out to our north and northwest. This activity is expected to push eastward throughout the morning and into the afternoon hours. Much of our eastern sections...east of US 27/127 will probably remain mostly dry through the early afternoon hours. The latest guidance continues to trend warmer, but overall, the spread and variance in the solutions is starting to diminish quickly. In general, we should a change over to snow develop to the west and eventually get into our western counties during the mid afternoon hours. Based on the latest projections a change over in the I-65 corridor which includes the Louisville...Elizabethtown... and Bowling Green areas looks to commence around 6-8 PM EST. Frankfort and Lexington should see the transition around 8-10 PM EST. Again, these are just projections and are subject to change throughout the day. For now, have adjusted the forecast slightly based on the above mentioned ideas. This results in a drier forecast for this morning in the east with a ramp up of wetter conditions toward mid-afternoon and into the evening hours. With regards to snowfall amounts, there are signals within the latest data that suggest a dry punch of air (dry slot) may punch into the region in the post frontal wake. This could result in lighter snow accumulations that currently forecast. However...with regards to impact, the snowfall amounts are not the primary concern here. The rapid fall of temperatures from the 20s/30s this evening to near or below zero by morning will lead to a rapid freeze up tonight making travel quite treacherous. Our plan again today is to evaluate the 12Z guidance suite this morning and make necessary adjustments throughout the day. .SHORT TERM (Now through Monday)... Issued at 320 PM EST Sat Jan 4 2014 ...SIGNIFICANT SNOWS LIKELY ON TODAY WITH HIGHEST ACCUMULATIONS IN SOUTHERN INDIANA... ...TEMPERATURES TO PLUNGE RAPIDLY THIS EVENING RESULTING IN A QUICK FREEZE UP AND DANGEROUS WIND CHILLS... The latest model solutions continue to trend a bit warmer with the system moving through today. This presents a challenge for forecasting snowfall totals as they will be highly dependent on how much moisture remains when temperatures fall enough for rain to change over to snow. However, even given the warmer solutions, it still looks like portions of southern Indiana could see some significant snow accumulations today, with lighter accumulations along and south of the Ohio River. Some light radar returns are showing up early this morning over southern Indiana. Temperatures have remained on the warmer side in the mid to upper 30s tonight, so this precipitation should be a cold rain with perhaps some sleet mixed in. As the surface low moves northeast along the Ohio River today precipitation will spread across the forecast area from west to east. Warmer air will be pulled up into central Kentucky and southern Indiana. Thus precipitation is expected to be mainly rain for most of the region through the early afternoon hours, though the far northern IN counties may see some snow mixed in through the day. As the surface low exits to the northeast late this afternoon it will drag the cold front through with temperatures plummeting in the wake of the front. Rain will quickly change over to snow late this afternoon into this evening as the cold air rushes in behind the front. Have pushed the changeover back a few more hours from the previous forecast given the current expected track of the low. As mentioned in the previous forecast discussion, some bands of snow may set up with this system and bring bursts of moderate to heavy snow at times. However, the progressive nature of the system does look to limit snowfall totals. Did also lower snowfall totals just a bit, with the highest amounts of around 5 inches in northern Dubois, Orange and Washington counties in IN. Will leave the Winter Storm Warning and Advisories in place as is, though the southern tier counties in the Warning may only reach criteria in part of the county. Elsewhere, 1-2" of snow is expected in the Advisory areas. As mentioned, temperatures will fall quickly behind the front. Winds will pick up with sustained winds of 15-25 mph and gusts up to 35 mph expected tonight and tomorrow. These wind speeds combined with temperatures dropping to near or below zero Fahrenheit will result in dangerous wind chills ranging from -15 to -30 F at times. Will therefore issue a Wind Chill Warning for southern IN and north central Kentucky and a Wind Chill Advisory for south central Kentucky beginning at 06Z Monday and running through 18Z Tuesday. .LONG TERM (Monday Night through Saturday)... Issued at 330 AM EST Sun Jan 5 2014 ...Bitterly Cold Temperatures Early in the Week...Mixed Precipitation Potential for Mid Week...then Moderating Temperatures and Rain Chances for Late in Week... MONDAY NIGHT-TUESDAY... Bitterly cold temperatures are still on track for early this week despite how much snow we do or don`t get today. Did come up a degree or two for low temps Mon night into Tues morning since forecast snowfall for today is less than initially thought over much of the area. However, even without a deep snow pack, temps should still bottom out in the single digits below zero in most locations Tues morning. Here are the record low temperatures for Tuesday morning (Jan 7) which will be challenged: Louisville: -8 in 1912 Lexington: -7 in 1912 Bowling Green: -11 in 1912 With steady westerly winds of 10 to 15 mph expected overnight Monday through Tues morning, dangerously low wind chills will result. Expect wind chills of -20 to -30 over southern Indiana and north central Kentucky where a Wind Chill Warning will be posted. Over south central KY, wind chills will range from -10 to -20 where a Wind Chill Advy will be posted. By Tues afternoon, temps will moderate to the single digits above zero to lower teens with resulting wind chill values improving to -5 to 5 range. Model soundings indicate a very shallow layer of moisture just off the sfc Mon night which may produce a few scattered flurries over the region. Tues looks dry as skies become partly cloudy to mostly sunny throughout the day. WEDNESDAY-THURSDAY... Models have come into agreement that a shortwave upper trough will traverse the southern CONUS pulling up Gulf moisture into the Ohio Valley Wed night-Thurs night. Models are in decent agreement with timing but vary some still on QPF amounts. Temp profiles are in question with quite a spread amongst models still. However, this overrunning precip setup would lend itself to some sort of wintry precip. Wed night temps are similar amongst the GFS/ECMWF and would support an area of snow and/or freezing rain. Thurs/Thurs night, model temps vary quite a bit so will go with a general rain/snow mix at this time and refine in coming forecasts. Suspect that after today`s storm pushes through the region, the models will come into better agreement for the mid week wintry precip event. FRIDAY-SATURDAY... By late in the week, a deeper trough will dive into the southwest CONUS allowing for better ridging/return flow into the Ohio Valley. This will result in temperatures returning closer to normal for the end of the week with more precipitation chances primarily in the form of rain. && .AVIATION (18Z TAF Update)... Updated at 1220 PM EST Sun Jan 5 2014 Conditions at the terminals will remain generally VFR early this afternoon before deteriorating late this afternoon and evening. Surface low pressure is expected to move northeastward into western KY this afternoon and into Ohio tonight. As this occurs, a strong Arctic cold front will swing eastward across the region. Surface winds will pick up across the region this afternoon and will be quick brisk. Sustained south to southwesterly winds of 12-15kts with gusts up to 25kts are likely. Precipitation out ahead of the front will fall in the form of rain and then quickly change over to snow in the wake of the front. A period of moderate to heavy snow will be possible at the terminals this evening. Best chances of moderate to heavy snow at BWG would be in the 06/01-02Z range, KSDF between 06/01-03Z and at KLEX 06/03-06Z time range. Ceilings are expected to decrease to the MVFR range later this afternoon and will likely drop into the IFR range this evening. Once the snow ends later this evening, ceilings are likely to recover slightly into the low end of the MVFR range. As the Arctic front pushes through, expect surface winds to swing around to the west/northwest and increase in speed. Sustained winds of 15-20kts with gusts to 30kts will be possible at all the terminals later this evening and will continue through the overnight period. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...WINTER WEATHER ADVISORY until 6 AM EST /5 AM CST/ Monday FOR KYZ023>032-061-062-070>072. WIND CHILL WARNING from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR KYZ023>043-045>049-053>057-067. WINTER WEATHER ADVISORY from 7 PM EST /6 PM CST/ this evening to 6 AM EST /5 AM CST/ Monday FOR KYZ033>043-045>049-053>057- 063>067-073>078-081-082. WIND CHILL ADVISORY from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR KYZ061>066-070>078-081-082. IN...WINTER WEATHER ADVISORY until 6 AM EST /5 AM CST/ Monday FOR INZ076>079-083-084-089>092. WIND CHILL WARNING from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR INZ076>079-083-084-089>092. && $$ Update.........MJ Short Term.....EER Long Term......AMS Aviation.......MJ
AREA FORECAST DISCUSSION
NWS LOUISVILLE KY
1158 AM EST Sun Jan 5 2014 ...Forecast Update... Updated at 1150 AM EST Sun Jan 5 2014 Precipitation continues to develop out over western KY this morning. Strong surge of warm air advection is taking place as temperatures are nearing 50 degrees down along the KY/TN border region. Probably will need to adjust our max temperatures for today down that way a little bit. Latest 12Z data generally has trended close to the previous 00Z and 06Z runs that were warmer and a little slower with the storm`s progression through the Ohio Valley. With that said, we feel that the current snowfall totals over our warning area (southern Indiana) is a bit too aggressive at this time. After careful coordination with ILN/IND/PAH we will be downgrading the warning across southern Indiana to a Winter Weather Advisory. We will also be adjusting the start time of the advisory products to better align with the thinking below. The Winter Weather Advisories will also be extended in time to go throughout the night due to the anticipated high impacts across the region. Current prognostic data fields and thermal analysis continues to show that we will see rain fall across the region this afternoon. As the surface low pressure system moves through western KY and into Ohio, a strong Arctic front will push in from the west. This front will usher in much colder air into the region. It appears that we will start to see a change over in our western sections around 4-5 PM EST...with a change over occurring in the I-65 corridor between 6-8 PM and in the I-75 corridor in the 9-11 PM time frame. Not really incorporating much of the NCEP model timing here but this is more of a blend of our in house high resolution WRF and the experimental HRRR which appears to have a good handle on the cold surge coming in from the west. We still expect to see a band of moderate to heavy snow come in behind the front. However, this will not last long as it will quickly move through the region. The models along with upstream satellite and observations show a dry slot developing across eastern OK and west-central AR which will likely pivot into our region late tonight. So while we will get in on the snow, it does not appear that it will hang around all that much. Though the snowfall is really the secondary story of this system. Of more concern will be the tumble in temperatures. We will see temperatures go from the 30s this evening down to near zero by dawn. This will lead to a quick freeze up of moisture on roads/objects. This combined with the snow will make travel treacherous tonight. With regards to snowfall accumulations, we are going to trim back amounts slightly across southern IN where we believe 2-4 inches is still likely. The 4 inch amounts would be most likely across our far northern portions of Dubois, Orange, Washington, Scott, and Jefferson counties in southern Indiana. Elsewhere across KY a general 1-3 inches will be possible. This will be a non-uniform snow...so some areas will pick up an inch here while other areas may pick up slightly more. We are currently in the production of updated products and those should be ready in the next 30-45 minutes. Updated web graphics and briefing slides will also be available early this afternoon. Additional meteorological details for later tonight and Monday will be forthcoming in the standard afternoon discussion which will be available by mid-afternoon. Update issued at 830 AM EST Sun Jan 5 2014 Early morning radar mosaics show our winter storm taking aim on the region. Rain showers have broken out across the region...mainly west of I-65 with more extensive precipitation out to our north and northwest. This activity is expected to push eastward throughout the morning and into the afternoon hours. Much of our eastern sections...east of US 27/127 will probably remain mostly dry through the early afternoon hours. The latest guidance continues to trend warmer, but overall, the spread and variance in the solutions is starting to diminish quickly. In general, we should a change over to snow develop to the west and eventually get into our western counties during the mid afternoon hours. Based on the latest projections a change over in the I-65 corridor which includes the Louisville...Elizabethtown... and Bowling Green areas looks to commence around 6-8 PM EST. Frankfort and Lexington should see the transition around 8-10 PM EST. Again, these are just projections and are subject to change throughout the day. For now, have adjusted the forecast slightly based on the above mentioned ideas. This results in a drier forecast for this morning in the east with a ramp up of wetter conditions toward mid-afternoon and into the evening hours. With regards to snowfall amounts, there are signals within the latest data that suggest a dry punch of air (dry slot) may punch into the region in the post frontal wake. This could result in lighter snow accumulations that currently forecast. However...with regards to impact, the snowfall amounts are not the primary concern here. The rapid fall of temperatures from the 20s/30s this evening to near or below zero by morning will lead to a rapid freeze up tonight making travel quite treacherous. Our plan again today is to evaluate the 12Z guidance suite this morning and make necessary adjustments throughout the day. .SHORT TERM (Now through Monday)... Issued at 320 PM EST Sat Jan 4 2014 ...SIGNIFICANT SNOWS LIKELY ON TODAY WITH HIGHEST ACCUMULATIONS IN SOUTHERN INDIANA... ...TEMPERATURES TO PLUNGE RAPIDLY THIS EVENING RESULTING IN A QUICK FREEZE UP AND DANGEROUS WIND CHILLS... The latest model solutions continue to trend a bit warmer with the system moving through today. This presents a challenge for forecasting snowfall totals as they will be highly dependent on how much moisture remains when temperatures fall enough for rain to change over to snow. However, even given the warmer solutions, it still looks like portions of southern Indiana could see some significant snow accumulations today, with lighter accumulations along and south of the Ohio River. Some light radar returns are showing up early this morning over southern Indiana. Temperatures have remained on the warmer side in the mid to upper 30s tonight, so this precipitation should be a cold rain with perhaps some sleet mixed in. As the surface low moves northeast along the Ohio River today precipitation will spread across the forecast area from west to east. Warmer air will be pulled up into central Kentucky and southern Indiana. Thus precipitation is expected to be mainly rain for most of the region through the early afternoon hours, though the far northern IN counties may see some snow mixed in through the day. As the surface low exits to the northeast late this afternoon it will drag the cold front through with temperatures plummeting in the wake of the front. Rain will quickly change over to snow late this afternoon into this evening as the cold air rushes in behind the front. Have pushed the changeover back a few more hours from the previous forecast given the current expected track of the low. As mentioned in the previous forecast discussion, some bands of snow may set up with this system and bring bursts of moderate to heavy snow at times. However, the progressive nature of the system does look to limit snowfall totals. Did also lower snowfall totals just a bit, with the highest amounts of around 5 inches in northern Dubois, Orange and Washington counties in IN. Will leave the Winter Storm Warning and Advisories in place as is, though the southern tier counties in the Warning may only reach criteria in part of the county. Elsewhere, 1-2" of snow is expected in the Advisory areas. As mentioned, temperatures will fall quickly behind the front. Winds will pick up with sustained winds of 15-25 mph and gusts up to 35 mph expected tonight and tomorrow. These wind speeds combined with temperatures dropping to near or below zero Fahrenheit will result in dangerous wind chills ranging from -15 to -30 F at times. Will therefore issue a Wind Chill Warning for southern IN and north central Kentucky and a Wind Chill Advisory for south central Kentucky beginning at 06Z Monday and running through 18Z Tuesday. .LONG TERM (Monday Night through Saturday)... Issued at 330 AM EST Sun Jan 5 2014 ...Bitterly Cold Temperatures Early in the Week...Mixed Precipitation Potential for Mid Week...then Moderating Temperatures and Rain Chances for Late in Week... MONDAY NIGHT-TUESDAY... Bitterly cold temperatures are still on track for early this week despite how much snow we do or don`t get today. Did come up a degree or two for low temps Mon night into Tues morning since forecast snowfall for today is less than initially thought over much of the area. However, even without a deep snow pack, temps should still bottom out in the single digits below zero in most locations Tues morning. Here are the record low temperatures for Tuesday morning (Jan 7) which will be challenged: Louisville: -8 in 1912 Lexington: -7 in 1912 Bowling Green: -11 in 1912 With steady westerly winds of 10 to 15 mph expected overnight Monday through Tues morning, dangerously low wind chills will result. Expect wind chills of -20 to -30 over southern Indiana and north central Kentucky where a Wind Chill Warning will be posted. Over south central KY, wind chills will range from -10 to -20 where a Wind Chill Advy will be posted. By Tues afternoon, temps will moderate to the single digits above zero to lower teens with resulting wind chill values improving to -5 to 5 range. Model soundings indicate a very shallow layer of moisture just off the sfc Mon night which may produce a few scattered flurries over the region. Tues looks dry as skies become partly cloudy to mostly sunny throughout the day. WEDNESDAY-THURSDAY... Models have come into agreement that a shortwave upper trough will traverse the southern CONUS pulling up Gulf moisture into the Ohio Valley Wed night-Thurs night. Models are in decent agreement with timing but vary some still on QPF amounts. Temp profiles are in question with quite a spread amongst models still. However, this overrunning precip setup would lend itself to some sort of wintry precip. Wed night temps are similar amongst the GFS/ECMWF and would support an area of snow and/or freezing rain. Thurs/Thurs night, model temps vary quite a bit so will go with a general rain/snow mix at this time and refine in coming forecasts. Suspect that after today`s storm pushes through the region, the models will come into better agreement for the mid week wintry precip event. FRIDAY-SATURDAY... By late in the week, a deeper trough will dive into the southwest CONUS allowing for better ridging/return flow into the Ohio Valley. This will result in temperatures returning closer to normal for the end of the week with more precipitation chances primarily in the form of rain. && .AVIATION (12Z TAF Update)... Updated at 610 AM EST Sun Jan 5 2014 Conditions will deteriorate through the day today as a low pressure system moves northeast across the lower Ohio Valley and drags a cold front through the area. Ceilings will lower to MVFR and then IFR as rain moves in. Rain will change over to light snow as the cold front moves through and temperatures drop. Some moderate to heavy snow bands may develop across the region this afternoon and evening. However, do not have enough confidence in one setting up over any of the terminals to include heavier snow in the TAFs at this time. The snow should end late tonight into early tomorrow morning Winds will be generally southerly today and will become gusty this afternoon as the front approaches. In the wake of the front winds will shift to the WNW and increase to 15-20 knot with gusts to around 30 knots. && .LMK WATCHES/WARNINGS/ADVISORIES... KY...WINTER WEATHER ADVISORY from 3 PM EST /2 PM CST/ this afternoon to 6 AM EST /5 AM CST/ Monday FOR KYZ023>032-061-062- 070>072. WIND CHILL WARNING from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR KYZ023>043-045>049-053>057-067. WINTER WEATHER ADVISORY from 7 PM EST /6 PM CST/ this evening to 6 AM EST /5 AM CST/ Monday FOR KYZ033>043-045>049-053>057- 063>067-073>078-081-082. WIND CHILL ADVISORY from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR KYZ061>066-070>078-081-082. IN...WINTER WEATHER ADVISORY from 3 PM EST /2 PM CST/ this afternoon to 6 AM EST /5 AM CST/ Monday FOR INZ076>079-083-084- 089>092. WIND CHILL WARNING from 1 AM EST /Midnight CST/ Monday to 1 PM EST /Noon CST/ Tuesday FOR INZ076>079-083-084-089>092. && $$ Update.........MJ Short Term.....EER Long Term......AMS Aviation.......EER
AREA FORECAST DISCUSSION
NWS GRAY ME
253 PM EST SUN JAN 5 2014 .SYNOPSIS... LOW PRESSURE WILL TRACK NORTH ALONG A STALLED FRONTAL BOUNDARY WELL TO THE WEST OF THE FORECAST AREA OVERNIGHT. LOW PRESSURE WILL CONTINUE NORTH THROUGH WESTERN QUEBEC ON MONDAY AND WILL DRIVE A STRONG COLD FRONT THROUGH THE REGION MONDAY AFTERNOON. A STRONG WESTERLY FLOW WILL PREVAIL BEHIND THE FRONT MONDAY NIGHT THROUGH TUESDAY. HIGH PRESSURE WILL BUILD IN FROM THE SOUTH WEDNESDAY THROUGH THURSDAY. A WARM FRONT WILL LIFT NORTH INTO THE FORECAST AREA THURSDAY NIGHT AND WILL PUSH NORTHEAST OF THE REGION ON FRIDAY. A COLD FRONT WILL PUSH THROUGH THE REGION FROM THE WEST ON SATURDAY WITH HIGH PRESSURE TO FOLLOW ON SUNDAY. && .NEAR TERM /THROUGH TONIGHT/... VERY INTERESTING SETUP WITH LOW PRESSURE PASSING WELL TO OUR WEST OVERNIGHT. HOWEVER...AT THE SAME TIME...A WEAK AREA OF LOW PERSSURE HAS ALREADY FORMED ALONG THE MID ATLANTIC COASTLINE. THIS IS AHEAD OF AND TO THE NORTH OF ALL MODELED GUIDANCE AT THIS TIME. EVEN THE MESO MODELS ARE HAVING A DIFFICULT TIME THIS MORNING...AS THEY ARE NOT CAPTURING THE PRECIPITATION OVER SOUTHERN NEW ENGLAND AT THE MOMENT. IN ANY CASE...PRECIPITATION WILL ENTER THE FORECAST AREA THIS EVENING. HAVE LEANED TOWARDS A COLD SOLUTION...A TAD COOLER THAN ALL AVAILABLE GUIDANCE. ATMOSPHERE STILL VERY COLD AND DRY...AND THERE WILL BE PLENTY OF EVAPORATION COOLING AS EVIDENT ON 12Z GYX SOUNDING. THEREFORE...HAVE EXPANDED THE WINTER WX ADIVSORIES TO INCLUDE THE COASTLINE. LATEST HRRR KEEPS TEMPERATURES BELOW FREEZING FOR MUCH OF THE COAST THROUGH AT LEAST MIDNIGHT BEFORE THE WARM UP. WARM UP MAY BE A TAD EARLIER AT PSM AND ALONG THE NH SEACOAST. ENOUGH DRY AIR IN PLACE TO POSSIBLY HOLD FOR SEVERAL HOURS OF SNOWFALL IN THE USUAL SUSPECT LOCATION OF THE FOOTHILLS. GFS ACTUALLY PICKS UP ON THIS FEATURE. USED A NON-DUIRNAL CURVE FOR THE OVERNIGHT MINS. HAVE SENT FORECAST SNOWFALL AND ICE MAPS. ICE WILL BE A SENSITIVE ISSUE AS WE HAVE HAD REPORTS OF ICE STILL IN THE TREES FROM THE ICE STORM PRIOR TO THE HOLIDAYS. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... STRONG COLD FRONT WILL CROSS THE REGION MONDAY AFTER A SIGNIFICANT WARM UP DURING THE AFTERNOON. TEMPS WILL GO FROM WELL IN THE 40S...TO A DEEP FREEZE OVER A SHORT PERIOD OF TIME. STRONGEST WINDS WILL HOLD OFF UNTIL THE PASSAGE OF THE UPPER LEVEL TROUGH. && .LONG TERM /TUESDAY THROUGH SUNDAY/... MORE BITTERLY COLD ARCTIC AIR IS EXPECTED TUESDAY THRU WEDNESDAY ON GUSTY WESTERLY WINDS WHICH WILL CREATE EXTREMELY COLD WIND CHILLS. THE UPSLOPE WESTERLY FLOW UNDER THE UPR LEVEL SYSTEM WILL CREATE SCT -SHSN ACROSS THE N/MT ZONES. FINALLY AS HIGH PRESSURE BUILDS IN FROM THE WEST AND THE AIR MASS CONTINUES TO WARM WE SHOULD SEE TEMPS CLIMB BACK TO MORE NORMAL LEVELS ALONG WITH LIGHTER WINDS ON THURSDAY. LATE THURSDAY NIGHT AND FRIDAY A WARM FRONT WITH WAA ALOFT WILL MOVE ACROSS NORTHERN NEW ENGLAND CREATING SOME LIGHT SNOW SHOWERS ON FRIDAY INTO FRI EVENING. TEMPS SHOULD REMAIN COLD ENOUGH TO BE SNOW. HIGH PRES AND A WARMER AIR MASS WILL TAKE CONTROL FOR SATURDAY. USED THE SUPERBLEND FOR TEMPS AND POPS. && .AVIATION /19Z SUNDAY THROUGH FRIDAY/... SHORT TERM...CONDITIONS DETEORATING TO IFR AND LIFR WITH FOG AND LOW CEILINGS DEVELOPING LATER TONIGHT. CONDITIONS IMPROVE MONDAY AFTERNOON. LONG TERM... MVFR IN SCT -SHSN MTN AREAS TUESDAY. GUSTY W WINDS THRU TUESDAY NGT AND INTO WEDNESDAY. MVFR CONDS PSBL FRI IN SCT SNW SHWRS. && .MARINE... SHORT TERM...HAVE ISSUED GALES FOR THE OUTER WATERS AND PENOBSCOT BAY FOR LATE TONIGHT AND MONDAY WITH A STRONG SOUTHERLY GRADIENT. SCA IN PLACE FOR CASCO BAY. LONG TERM... AN EXTENDED PERIOD OF FAIRLY STRONG WINDS AND ROUGH SEAS WITH AT LEAST SCA CONDITIONS (AND POSSIBLY GALES OVER THE OPEN WATERS) THRU TUESDAY NGT AND INTO WEDNESDAY. WINDS THEN SEAS SLOWLY EASE UP LATE WEDNESDAY THRU THURSDAY. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR MEZ018. WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 10 AM EST MONDAY FOR MEZ007>009-012>014-019>022. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR MEZ023>028. NH...WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 7 AM EST MONDAY FOR NHZ003>010-013. WINTER WEATHER ADVISORY FROM 9 PM THIS EVENING TO 10 AM EST MONDAY FOR NHZ001-002. WINTER WEATHER ADVISORY FROM 7 PM THIS EVENING TO 3 AM EST MONDAY FOR NHZ014. MARINE...SMALL CRAFT ADVISORY FROM 3 AM TO 3 PM EST MONDAY FOR ANZ153. GALE WARNING FROM 3 AM TO 3 PM EST MONDAY FOR ANZ150>152-154. && $$ JC/RAM
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
519 PM EST SUN JAN 5 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 445 PM EST SUN JAN 5 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THE CENTER OF AN ELONGATED POLAR VORTEX OVER NRN ONTARIO. A SHORTWAVE WAS DIVING SE THRU THE NRN PLAINS...CAUSING THE ELONGATION OF THE VORTEX INTO THE NRN PLAINS. THE CORE OF THE VERY COLD ARCTIC AIR MASS RESIDES FROM NRN ONTARIO INTO SCNTRL CANADA AND THE FAR NRN PLAINS. PER 12Z RAOBS... 850MB TEMPS ARE IN THE -29C TO -34C RANGE ACROSS SCNTRL CANADA INTO THE FAR NCNTL CONUS. LATEST RUC ANALYSIS INDICATES 850MB TEMPS RANGING FROM -25C OVER WRN LAKE SUPERIOR TO AROUND -19C OVER FAR SE LAKE SUPERIOR. OF COURSE...THIS IS LEADING TO LES OFF LAKE SUPERIOR IN WNW LOW-LEVEL FLOW. HOWEVER...VERY DRY AIR MASS/LOW INVERSION (3-5KFT LOWEST W PER LATEST RUC) IS GREATLY LIMITING LES INTENSITY. PLUS...IT DOESN`T HELP THAT VERY COLD AIR HAS ELIMINATED THE DGZ FOR THE WRN LAKE SUPERIOR LES. ON THE OTHER HAND...THE RESULTING SMALL SNOWFLAKES ARE LEADING TO SHARPLY REDUCED VIS WHERE LES IS OCCURRING (VIS AT KCMX HAS BEEN DOWN TO 1/2SM AT TIMES THIS AFTN...AND WEBCAMS HAVE SHOWN QUITE LOW VIS AT TIMES). AS THE ELONGATED POLAR VORTEX SWINGS INTO THE UPPER GREAT LAKES MON...THERE WILL BE A SIGNIFICANT LIFTING OF THE INVERSION AND DEEPENING OF MOISTURE. THIS WILL GRADUALLY BEGIN TONIGHT...BUT WILL LARGELY TAKE PLACE DURING THE DAY MON. AS A RESULT...THERE WILL BE A NOTABLE INCREASE IN LAKE EFFECT SNOW COVERAGE...AND INTENSITY WILL INCREASE AS WELL. HOWEVER...WITH THE COLD AIR MASS ELIMINATING THE DGZ...SNOW-TO-WATER RATIOS WILL BE POOR...PROBABLY DOWN TOWARD 10 TO 1 AS HAS BEEN OBSERVED IN PAST ARCTIC AIR MASSES SIMILAR TO THE MAGNITUDE OF THIS ONE. SNOW WILL BE POWDERY AND VERY EFFECTIVE AT REDUCING VIS. WITH THE INCREASE IN LES COVERAGE...WHITEOUTS WILL PROBABLY BECOME NEARLY CONSTANT IN THE SNOWBELTS FAVORED BY NW WINDS LATE TONIGHT AND ESPECIALLY MON. TONIGHT...LOW-LEVEL WINDS WILL VEER MORE TOWARD THE NNW IN RESPONSE TO THE DEEPENING LOW LIFTING NNE THRU THE LWR LAKES. THE VEERING WILL BE MORE PRONOUNCED OVER THE ERN LAKE WHERE LAND BREEZE ENHANCEMENT OFF ONTARIO WILL AID THE VEERING. THIS WILL LEAD TO STRENGTHENING CONVERGENCE INTO ALGER/LUCE/SCHOOLCRAFT COUNTIES. WITH THE DGZ STILL LINGERING IN THE LOWER PART OF THE CONVECTIVE LAYER IN THAT AREA...SHOULD BE ABLE TO GET ACCUMULATIONS INTO THE 2 TO 4 INCH RANGE. COMBINED WITH SOME INCREASE IN WINDS TO GENERATE BLSN...ADVY LOOKS ON TRACK FOR THAT AREA. EVEN THOUGH THE DGZ IS ELIMINATED MON...SIMILAR ACCUMULATIONS SHOULD OCCUR GIVEN LINGERING ENHANCED CONVERGENCE AND DEEP MOISTURE PROFILE. OUT W...SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 1-2 TO PERHAPS 3IN/12HR TONIGHT/MON. AS FOR TEMPS/WIND CHILLS...WITH LOW-LEVEL WINDS VEERING TONIGHT... THERE SHOULD BE AN INCREASE IN LAKE EFFECT CLOUD COVER ACROSS MUCH OF THE AREA. HAVE THUS OPTED TO RAISE MINS A FEW DEGREES IN MANY LOCATIONS. TEMPS MAY STILL BOTTOM OUT AROUND -25F OVER THE FAR W ALONG THE MI/WI BORDER...BUT IF CLOUD COVER IS QUICKER TO DEVELOP AND MORE PERSISTENT...TEMPS MAY NOT FALL THAT LOW. IN GENERAL...MOST OF THE W HALF OF UPPER MI WILL SEE MINS IN THE -10F TO -20F RANGE WITH WIND CHILLS FALLING TO -30 TO -45F. WITH THE CORE OF THE COLD OVER THE AREA MON...EXPECT INTERIOR W LOCATIONS TO FAIL TO RISE ABOVE -10F. ONLY AREAS TO GET JUST ABOVE 0F WILL BE OVER THE E. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 515 PM EST SUN JAN 5 2014 .MONDAY NIGHT INTO TUESDAY...W TO WNW LOW LEVEL WINDS WILL CONTINUE BETWEEN LOW PRES LIFTING NNE INTO HUDSON BAY AND ARCTIC HIGH PRES BUILDING FROM THE NRN PLAINS TO THE UPPER MS VALLEY. 850 MB TEMPS WILL GRADUALLY MODERATE FROM THE -25C TO -30C RANGE TO -17C TO -22C FROM 00Z/TUE TO 00Z/WED. HOWEVER...SFC TEMPS WILL CLIMB ONLY SLIGHTLY. WINDS WILL ALSO DIMINISH TO AROUND 10 MPH BY TUE MORNING. HOWEVER...WITH TEMPS AGAIN FALLING INTO THE -12 TO -25 RANGE...WIND CHILL VALUES OF -30 TO -45 WILL REMAIN IN THE WARNING CATEGORY OVER MOST OF THE CWA. LES WILL PERSIST FOR THE KEWEENAW AND THE NE CWA(E OF MUNISING). THE HIGHER RES MODELS SUGGEST THAT LOW LEVEL CONV OVER THE WRN LAKE MAY BOOST SNOWFALL RATES INTO THE KEWEENAW(NEAR OR JUST SOUTH OF HOUGHTON) AND NEAR THE PICTURED ROCKS AND GRAND MARAIS. HOWEVER...WITH THE VERY COLD AIR AND NO DGZ AVAILABLE...SLR VALUES WILL REMAIN LOW AND LIMIT SNOW ACCUMULATIONS TO THE 1 TO 3 INCH PER 12 HOUR WEST AND POSSIBLY 2 TO 4 INCHES EAST. TUE NIGHT AND WED...WRLY FLOW LES WILL CONTINUE AS THE AIRMASS MODERATES. WITH THE DGZ MOVING BACK CLOSER TO THE CONVECTIVE LAYER...SLR VALUES WILL INCREASE. HOWEVER...THE VERY AIR UPSTREAM WILL REMAIN UNFAVORABLE FOR MORE SIGNIFICANT LES. SO...SNOWFALL RATES WILL GENERALLY REMAIN LIGHT...IN THE 1 TO 3 INCH RANGE...WITH THE GREATEST AMOUNTS REMAINING OVER THE KEWEENAW AND ALONG THE SHORELINE NEAR GRAND MARAIS. WIND CHILLS WILL ALSO NOT BE AS SEVERE AS WINDS DIMINISH CLOSER TO 5 MPH INLAND AS TEMPS DROP INTO THE -10 TO -20 RANGE GIVING WIND CHILL VALUES FROM -20 TO -30. THU-SUN...THE MODELS SHOW A TRANSITION TO A MORE ZONAL PATTERN WITH SEPARATED NRN AND SRN STREAMS. AFTER BACKING WINDS TO SW WILL END THE LES OVER THE KEWEENAW THU...MAINLY DRY WEATHER IS EXPECTED INTO THE WEEKEND WITH MUCH MILDER CONDITIONS. HIGH TEMPS SHOULD CLIMB BACK INTO THE UPPER 20S FRI AND TO AROUND 30 FOR THE WEEKEND. ALTHOUGH THE 00Z/05 ECMWF RUN SHOWED A MORE PHASED TROUGH BY SUN THAT BRINGS UP ENOUGH WARM AIR AND MOISTURE FOR RAIN...THE 12Z/05 RUN FLIPPED BACK TO A MORE SEPARATE NRN STREAM WITH THE SRN SHRTWV SLIDING INTO THE LOWER MS VALLEY SIMILAR TO THE GFS/GEFS. HOWEVER...CONFIDENCE IN ANY WEATHER DETAILS BEYOND THE MILDER AIR FOR THE WEEKEND REMAINS LOW. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1217 PM EST SUN JAN 5 2014 WITH EXTREMELY COLD AIR FLOWING INTO THE UPPER LAKES OVER THE NEXT COUPLE OF DAYS...LAKE EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN AN OVERALL NW FLOW. WITH MIXED LAYER WINDS TENDING TO VEER SLIGHTLY...-SHSN WILL BECOME INCREASINGLY PERSISTENT AT KIWD. EXPECT A TREND TO PREVAILING IFR CONDITIONS THIS AFTN/EVENING. WITH VERY COLD AIR MASS LEADING TO SMALL SNOWFLAKES THAT ARE HIGHLY EFFECTIVE AT REDUCING VIS...IT`S CERTAINLY POSSIBLE KIWD MAY FALL INTO A PREVAILING LIFR CONDITION. KCMX WILL REMAIN UNDER CONSTANT LAKE EFFECT SNOW SHOWERS. DURING THE AFTN...EXPECT CONDITIONS TO VARY BTWN LIFR AND IFR. AS SNOWFLAKES BECOME SMALLER AND WINDS INCREASE LEADING TO BLSN...PREVAILING LIFR CONDITIONS WILL TAKE OVER TONIGHT. AT SOME POINT...MOST LIKELY BY DAYBREAK...EXPECT CONDITIONS TO BECOME PREVAILING VLIFR AT KCMX. CONDITIONS COULD THEN CERTAINLY REMAIN VLIFR NEARLY CONTINUOUSLY THRU AT LEAST TUE MORNING. AT KSAW...INITIALLY DRY AIR AND DOWNSLOPE NW FLOW WILL RESULT IN VFR CONDITIONS FOR THE NEXT FEW HRS. LAKE EFFECT CLOUDS WILL ARRIVE LATER THIS AFTN AS THE FLOW VEERS SLIGHTLY AND ALLOWS MORE LAKE SUPERIOR MODIFIED...MOISTER AIR TO ARRIVE. ALTHOUGH THE LOW-LEVEL NW WINDS WILL NOT BE IDEAL...THE ARRIVAL OF DEEPER MOISTURE WILL RESULT IN -SHSN TONIGHT/MON MORNING ALONG WITH MORE SOLID MVFR CONDITIONS. && .MARINE...(FOR THE 4 PM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 515 PM EST SUN JAN 5 2014 PRES GRADIENT WILL SLOWLY INCREASE TONIGHT THRU MON...RESULTING IN AN INCREASE IN WINDS. LOOKS LIKE 35KT GALES WILL DEVELOP OVER PORTIONS OF ERN LAKE SUPERIOR LATE TONIGHT OR MON MORNING...AIDED BY LAND BREEZE CONVERGENCE. AS PRES GRADIENT TIGHTENS A LITTLE MORE... WILL NEED TO WATCH FOR AN EXPANSION OF GALES TO MORE OF CNTRL/ERN LAKE SUPERIOR MON NIGHT/TUE. WITH VERY COLD AIR MASS OVER THE AREA FOR THE NEXT COUPLE OF DAYS...WINDS/WAVES WILL LEAD TO HEAVY FREEZING SPRAY OVER MUCH OF LAKE SUPERIOR. WINDS WILL DIMINISH DURING THE MIDWEEK PERIOD AS THE COLD EASES AND HIGH PRES MOVES ACROSS THE GREAT LAKES. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084. WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR MIZ002-009-010-084. LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ006-007- 014-085. WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR MIZ006-007-014-085. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-243>245-248>251-263>267. GALE WARNING FROM 7 AM MONDAY TO 1 AM EST WEDNESDAY FOR LSZ265- 266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...JLB AVIATION...ROLFSON MARINE...ROLFSON
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
446 PM EST SUN JAN 5 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 445 PM EST SUN JAN 5 2014 WATER VAPOR IMAGERY AND RUC ANALYSIS SHOW THE CENTER OF AN ELONGATED POLAR VORTEX OVER NRN ONTARIO. A SHORTWAVE WAS DIVING SE THRU THE NRN PLAINS...CAUSING THE ELONGATION OF THE VORTEX INTO THE NRN PLAINS. THE CORE OF THE VERY COLD ARCTIC AIR MASS RESIDES FROM NRN ONTARIO INTO SCNTRL CANADA AND THE FAR NRN PLAINS. PER 12Z RAOBS... 850MB TEMPS ARE IN THE -29C TO -34C RANGE ACROSS SCNTRL CANADA INTO THE FAR NCNTL CONUS. LATEST RUC ANALYSIS INDICATES 850MB TEMPS RANGING FROM -25C OVER WRN LAKE SUPERIOR TO AROUND -19C OVER FAR SE LAKE SUPERIOR. OF COURSE...THIS IS LEADING TO LES OFF LAKE SUPERIOR IN WNW LOW-LEVEL FLOW. HOWEVER...VERY DRY AIR MASS/LOW INVERSION (3-5KFT LOWEST W PER LATEST RUC) IS GREATLY LIMITING LES INTENSITY. PLUS...IT DOESN`T HELP THAT VERY COLD AIR HAS ELIMINATED THE DGZ FOR THE WRN LAKE SUPERIOR LES. ON THE OTHER HAND...THE RESULTING SMALL SNOWFLAKES ARE LEADING TO SHARPLY REDUCED VIS WHERE LES IS OCCURRING (VIS AT KCMX HAS BEEN DOWN TO 1/2SM AT TIMES THIS AFTN...AND WEBCAMS HAVE SHOWN QUITE LOW VIS AT TIMES). AS THE ELONGATED POLAR VORTEX SWINGS INTO THE UPPER GREAT LAKES MON...THERE WILL BE A SIGNIFICANT LIFTING OF THE INVERSION AND DEEPENING OF MOISTURE. THIS WILL GRADUALLY BEGIN TONIGHT...BUT WILL LARGELY TAKE PLACE DURING THE DAY MON. AS A RESULT...THERE WILL BE A NOTABLE INCREASE IN LAKE EFFECT SNOW COVERAGE...AND INTENSITY WILL INCREASE AS WELL. HOWEVER...WITH THE COLD AIR MASS ELIMINATING THE DGZ...SNOW-TO-WATER RATIOS WILL BE POOR...PROBABLY DOWN TOWARD 10 TO 1 AS HAS BEEN OBSERVED IN PAST ARCTIC AIR MASSES SIMILAR TO THE MAGNITUDE OF THIS ONE. SNOW WILL BE POWDERY AND VERY EFFECTIVE AT REDUCING VIS. WITH THE INCREASE IN LES COVERAGE...WHITEOUTS WILL PROBABLY BECOME NEARLY CONSTANT IN THE SNOWBELTS FAVORED BY NW WINDS LATE TONIGHT AND ESPECIALLY MON. TONIGHT...LOW-LEVEL WINDS WILL VEER MORE TOWARD THE NNW IN RESPONSE TO THE DEEPENING LOW LIFTING NNE THRU THE LWR LAKES. THE VEERING WILL BE MORE PRONOUNCED OVER THE ERN LAKE WHERE LAND BREEZE ENHANCEMENT OFF ONTARIO WILL AID THE VEERING. THIS WILL LEAD TO STRENGTHENING CONVERGENCE INTO ALGER/LUCE/SCHOOLCRAFT COUNTIES. WITH THE DGZ STILL LINGERING IN THE LOWER PART OF THE CONVECTIVE LAYER IN THAT AREA...SHOULD BE ABLE TO GET ACCUMULATIONS INTO THE 2 TO 4 INCH RANGE. COMBINED WITH SOME INCREASE IN WINDS TO GENERATE BLSN...ADVY LOOKS ON TRACK FOR THAT AREA. EVEN THOUGH THE DGZ IS ELIMINATED MON...SIMILAR ACCUMULATIONS SHOULD OCCUR GIVEN LINGERING ENHANCED CONVERGENCE AND DEEP MOISTURE PROFILE. OUT W...SNOW ACCUMULATIONS WILL BE ON THE ORDER OF 1-2 TO PERHAPS 3IN/12HR TONIGHT/MON. AS FOR TEMPS/WIND CHILLS...WITH LOW-LEVEL WINDS VEERING TONIGHT... THERE SHOULD BE AN INCREASE IN LAKE EFFECT CLOUD COVER ACROSS MUCH OF THE AREA. HAVE THUS OPTED TO RAISE MINS A FEW DEGREES IN MANY LOCATIONS. TEMPS MAY STILL BOTTOM OUT AROUND -25F OVER THE FAR W ALONG THE MI/WI BORDER...BUT IF CLOUD COVER IS QUICKER TO DEVELOP AND MORE PERSISTENT...TEMPS MAY NOT FALL THAT LOW. IN GENERAL...MOST OF THE W HALF OF UPPER MI WILL SEE MINS IN THE -10F TO -20F RANGE WITH WIND CHILLS FALLING TO -30 TO -45F. WITH THE CORE OF THE COLD OVER THE AREA MON...EXPECT INTERIOR W LOCATIONS TO FAIL TO RISE ABOVE -10F. ONLY AREAS TO GET JUST ABOVE 0F WILL BE OVER THE E. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 448 AM EST SUN JAN 5 2014 THE MAIN CONCERN FOR THE LONG TERM FORECAST WILL BE EXTREMELY COLD TEMPERATURES/WIND CHILLS AND REDUCED VISIBILITIES FROM LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW. LOW PRESSURE TRAVELING FROM THE OHIO VALLEY TODAY WILL REACH QUEBEC BY MONDAY MORNING. MEANWHILE...A COLD ARCTIC AIRMASS/HIGH PRESSURE WILL SINK FROM THE CANADIAN PRAIRIE INTO THE MIDWEST AND CENTRAL PLAINS. AS THIS HIGH SINKS TOWARDS THE GULF COAST MONDAY NIGHT...THE LOW OVER QUEBEC WILL DRIFT WESTWARD INTO JAMES BAY. THIS PATTERN WILL KEEP UPPER MICHIGAN IN A MODERATE WEST-NORTHWESTERLY FLOW THROUGH WEDNESDAY...AS A TIGHTER PRESSURE GRADIENT SITS OVER THE AREA. ADDITIONALLY...A 500MB LOW WILL CENTER ITSELF OVER UPPER MI MONDAY MORNING...THEN DRIFT SLOWLY NORTHEASTWARD INTO ONTARIO AND QUEBEC. WITH THE LOW CENTERED OVER UPPER MI 850-500MB QVECTOR CONVERGENCE IS MAXIMIZED OVER THE EASTERN U.P. AND LOWER MI. WITH NORTHWESTERLY WINDS MOVING THE COLD ARCTIC AIR OVER LAKE SUPERIOR...KEPT POPS IN NORTHWEST WIND FAVORED SNOWBELTS. ALSO INCREASED POPS IN THE EASTERN CWA AS THE UPPER LEVEL SUPPORT CROSSES THROUGH THE AREA WITH THE TROUGH. WINDS GENERALLY REMAIN NORTHWESTERLY THROUGH MONDAY AFTERNOON...THEN BEGIN TO BACK TOWARDS THE WEST-NORTHWEST WIND DIRECTION. ADJUSTED POPS ACCORDINGLY...WITH THE MAIN CORE OF PRECIPITATION IN THE EASTERN U.P. SHIFTING TO AREAS FAVORED BY WNW WINDS...MAINLY EAST OF MUNISING. ON TUESDAY SEVERAL SMALL SHORTWAVES SNEAK ALONG THE BASE OF THE TROUGH ALOFT AS IT MOVES EASTWARD...AND WNW WINDS BECOME MORE WESTERLY TOWARDS THE EVENING. MOST OF THE SNOW BY LATE TUESDAY AFTERNOON WILL BE OVER THE KEWEENAW AND EAST OF GRAND MARAIS. LIMITING FACTORS TO SIGNIFICANT ACCUMULATIONS WILL BE THE EXTREMELY COLD/DRY AIRMASS. THIS SENDS THE DGZ CRASHING INTO THE GROUND FOR MOST LOCATIONS...ESPECIALLY MONDAY NIGHT INTO TUESDAY AFTERNOON. AS A RESULT SNOW RATIOS WILL BE ON THE ORDER OF 15-18:1 AND FLAKES VERY FINE. AS FAR AS MOISTURE GOES...PWATS DURING THIS TIME FRAME DROP TO NEAR 15 PERCENT OF NORMAL FOR UPPER MI. OVERALL...FROM MONDAY MORNING THROUGH TUESDAY MORNING...HAVE 2-4 INCHES FOR AREAS FAVORED BY WEST-NORTHWEST WINDS. TUESDAY MORNING INTO WED MORNING ONLY HAVE 1-3 INCHES FOR THE SAME AREAS...MAINLY THE KEWEENAW AND EAST OF MUNISING NEAR LAKE SUPERIOR. THE COLD ARCTIC AIRMASS WILL BRING LOW TEMPERATURES CRASHING DOWN TO -27F OUT WEST...AND THE TEENS BELOW ZERO EAST FOR MONDAY NIGHT. AREAS NEAR THE LAKE WILL SEE TEMPERATURES DROP DOWN TO THE SINGLE DIGITS BELOW ZERO FARTHER EAST AND OVER THE KEWEENAW. WITH THE STRONGER WINDS OVER THE AREA HOWEVER...WIND CHILLS WILL DROP AS LOW AS -50F ACROSS THE WEST...AND MAINLY THE -30S AND -40S ELSEWHERE...EVEN NEAR THE LAKE. THOUGH SNOW ACCUMULATIONS WILL NOT BE HAZARDOUS BY THEMSELVES...THE COMBINATION OF SNOW...BLOWING SNOW...AND DANGEROUSLY LOW TEMPERATURES/WIND CHILLS WARRANT A LAKE EFFECT SNOW ADVISORY FOR AREAS IN THE EAST...MAINLY FOR ALGER/LUCE/SCHOOLCRAFT COUNTIES. WIND CHILLS WILL REACH ADVISORY CRITERIA...AND THE COMBINATION OF SNOW AND BLOWING SNOW/DUE TO WINDS AROUND 30 MPH/ WILL REDUCE VISIBILITIES DRAMATICALLY...ESPECIALLY WITH THE FINER FLAKES. ELSEWHERE...HAVE ONLY THE WIND CHILL WARNING IN EFFECT FOR THE MONDAY-TUESDAY TIME FRAME. THE KEWEENAW WILL ALSO SEE STRONG WINDS...GUSTING TO 25 TO 30 MPH...AND PERSISTENT LAKE EFFECT SNOW WITH AREAS OF BLOWING SNOW DURING THE MONDAY-TUESDAY TIME FRAME. HAVE INCLUDED THIS WORDING IN THE WIND CHILL WARNING FOR THE KEWEENAW/HOUGHTON COUNTIES FOR SIMPLICITY WITH HEADLINES. WINDS WILL GRADUALLY DIE DOWN FROM WEDNESDAY INTO THURSDAY AS THE HIGH CENTERS ITSELF OVER THE GREAT LAKES. LIGHT AND VARIABLE WINDS WILL GRADUALLY TRANSITION TO MORE MODERATE SOUTH TO SOUTHWESTERLY WINDS AS THE HIGH SHIFTS EASTWARD TOWARDS THE NEW ENGLAND STATES...AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA. SOME OF THE MODELS ATTEMPT TO BRING A WEAK SHORTWAVE TROUGH INTO THE MIDWEST LATE FRIDAY AFTERNOON AND SATURDAY...BUT OTHERS KEEP MORE ZONAL FLOW OVER THE AREA. WILL KEEP THE CONSENSUS POPS DURING THIS TIME FRAME HOWEVER...WITH THE WNW-LAKE EFFECT MOVING OUT INTO THE LAKE AS WINDS BACK TO THE SOUTH-SOUTHWEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1217 PM EST SUN JAN 5 2014 WITH EXTREMELY COLD AIR FLOWING INTO THE UPPER LAKES OVER THE NEXT COUPLE OF DAYS...LAKE EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN AN OVERALL NW FLOW. WITH MIXED LAYER WINDS TENDING TO VEER SLIGHTLY...-SHSN WILL BECOME INCREASINGLY PERSISTENT AT KIWD. EXPECT A TREND TO PREVAILING IFR CONDITIONS THIS AFTN/EVENING. WITH VERY COLD AIR MASS LEADING TO SMALL SNOWFLAKES THAT ARE HIGHLY EFFECTIVE AT REDUCING VIS...IT`S CERTAINLY POSSIBLE KIWD MAY FALL INTO A PREVAILING LIFR CONDITION. KCMX WILL REMAIN UNDER CONSTANT LAKE EFFECT SNOW SHOWERS. DURING THE AFTN...EXPECT CONDITIONS TO VARY BTWN LIFR AND IFR. AS SNOWFLAKES BECOME SMALLER AND WINDS INCREASE LEADING TO BLSN...PREVAILING LIFR CONDITIONS WILL TAKE OVER TONIGHT. AT SOME POINT...MOST LIKELY BY DAYBREAK...EXPECT CONDITIONS TO BECOME PREVAILING VLIFR AT KCMX. CONDITIONS COULD THEN CERTAINLY REMAIN VLIFR NEARLY CONTINUOUSLY THRU AT LEAST TUE MORNING. AT KSAW...INITIALLY DRY AIR AND DOWNSLOPE NW FLOW WILL RESULT IN VFR CONDITIONS FOR THE NEXT FEW HRS. LAKE EFFECT CLOUDS WILL ARRIVE LATER THIS AFTN AS THE FLOW VEERS SLIGHTLY AND ALLOWS MORE LAKE SUPERIOR MODIFIED...MOISTER AIR TO ARRIVE. ALTHOUGH THE LOW-LEVEL NW WINDS WILL NOT BE IDEAL...THE ARRIVAL OF DEEPER MOISTURE WILL RESULT IN -SHSN TONIGHT/MON MORNING ALONG WITH MORE SOLID MVFR CONDITIONS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 448 AM EST SUN JAN 5 2014 A GALE WATCH IS IN EFFECT FOR CENTRAL AND EASTERN LAKE SUPERIOR MONDAY MORNING THROUGH TUESDAY NIGHT...AND A HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT... EXPECT NW WINDS 20-25 KTS THIS MORNING TO INCREASE TO 25-30 KTS LATER TODAY AND TONIGHT AS THE PRES GRADIENT OVER THE UPPER GREAT LAKES SHARPENS TO THE NW OF A DEEPENING LO PRES MOVING NE THRU THE SE GREAT LAKES INTO SE CANADA. THERE MAY BE A FEW GALE FORCE GUSTS OVER PORTIONS OF THE E LAKE LATE TONIGHT AS WELL. WITH ARCTIC AIR PERSISTING OVER THE AREA...EXPECT PERIODS OF HEAVY FREEZING SPRAY... ESPECIALLY OVER THE E HALF WHERE WINDS WILL BE STRONGEST. LAKE SUPERIOR WILL BE CAUGHT THIS TIGHT PRESSURE GRADIENT BETWEEN STRONG ARCTIC HIGH PRESSURE OVER THE PLAINS AND STRONG LOW PRESSURE OVER QUEBEC MONDAY INTO TUESDAY. AS A RESULT...WEST NORTHWEST GALES TO 35 KNOTS WILL OCCUR OVER MAINLY CENTRAL AND EASTERN LAKE SUPERIOR ON MONDAY AFTERNOON...AND WEST NORTHWEST GALES TO 40 KNOTS WILL OCCUR ON TUESDAY AFTERNOON. WINDS ON WESTERN LAKE SUPERIOR WILL LARGELY REMAIN WEST-NORTHWEST AT 20 TO 30 KNOTS DURING THIS TIME. ADDITIONALLY...COLD ARCTIC AIR IN PLACE OVER LAKE SUPERIOR COMBINED WITH THE STRONG WINDS WILL LEAD TO HEAVY FREEZING SPRAY FOR ALL OF THE LAKE THROUGH WEDNESDAY MORNING. ON WEDNESDAY AND THURSDAY HIGH PRESSURE WILL MAKE ITS WAY NORTHWARD...CENTERING ITSELF OVER THE GREAT LAKES. AS A RESULT...GUSTY WEST NORTHWEST WINDS WILL DIE DOWN...EVENTUALLY BACKING SOUTHWEST AT LESS THAN 10 KNOTS BY THURSDAY. AS THE HIGH SHIFTS TO THE NEW ENGLAND STATES AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA FRIDAY AFTERNOON AND SATURDAY...SOUTHWESTERLY WINDS WILL PICK UP TO 15 TO 25 KNOTS OVER ALL OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING UNTIL 11 AM EST /10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084. WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR MIZ002-009-010-084. LAKE EFFECT SNOW ADVISORY UNTIL 7 PM EST MONDAY FOR MIZ006-007- 014-085. WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR MIZ006-007-014-085. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-243>245-248>251-263>267. GALE WARNING FROM 7 AM MONDAY TO 1 AM EST WEDNESDAY FOR LSZ265- 266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...ROLFSON LONG TERM...MCD AVIATION...ROLFSON MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS MARQUETTE MI
1218 PM EST SUN JAN 5 2014 .SHORT TERM...(TODAY AND TONIGHT) ISSUED AT 448 AM EST SUN JAN 5 2014 00Z RAOBS/LATEST WV IMAGERY AND RUC ANALYSIS SHOW DEEP POLAR VORTEX CENTERED OVER SCENTRAL CANADA...WITH CORE OF ARCTIC AIRMASS ACCOMPANIED BY 00Z H5/H85/H925 TEMPS AS LO AS -43C/-31C/-34C AT THE PAS MANITOBA. UPR MI IS ON THE PERIPHERY OF THE VERY COLD AIRMASS ATTM...WITH 00Z H85 TEMPS RANGING FM -6C AT GRB TO -24C AT INL. LVL WNW FLOW TO THE E OF SFC HI PRES IN THE NRN PLAINS IS ADVECTING THE COLDER AIR INTO UPR MI...BUT RELATIVELY LIGHT WINDS HAVE SLOWED THE ADVECTION. THIS COLD FLOW OVER THE RELATIVELY WARM WATERS OF LK SUP IS CAUSING THE TYPICAL LK CLDS/LES IN THE FAVORED SN BELTS...BUT LO INVRN BASE ARND H9 AS SHOWN ON THE 00Z INL/GRB RAOBS AS WELL AS DRY NATURE OF THE LLVLS IS LIMITING THE INTENSITY OF THE SHSN. OTRW... QUITE A BIT OF HI CLD IS STREAMING OVER MAINLY THE SE HALF OF THE CWA WELL TO THE N OF SFC LO PRES DVLPG IN THE LOWER MS RIVER VALLEY. MAIN FCST CONCERNS THRU THE SHORT TERM FOCUS ON TEMPS/WIND CHILLS/ GOING HEADLINES AS WELL AS LES/BLSN. TODAY...THE CORE OF THE ARCTIC AIR OVER SCENTRAL CANADA EARLY THIS MRNG IS FCST TO DROP OVER MN BY 00Z MON. AS THE TROF OVER CENTRAL NAMERICA DEEPENS...THE SFC LO NOW OVER THE LOWER MS RIVER VALLEY IS PROGGED TO DEEPEN AND MOVE INTO THE OH RIVER VALLEY. ALTHOUGH THE LARGER SCALE FORCING/ASCENT/DEEP MOISTENING ASSOCIATED WITH THIS LO WL REMAIN TO THE E-SE OF UPR MI...THE PRES GRADIENT/LLVL NW FLOW OVER THE AREA IS FCST TO SHARPEN AND INCRS THE ADVECTION OF THE COLDER AIR INTO THE CWA. MODEL CONSENSUS SHOWS H85 TEMPS FALLING FM -23C OVER THE NW/-14C OVER THE SE AT 12Z TO -29C OVER THE NW/-19C OVER THE SE BY 00Z MON. AS A RESULT...THE DIURNAL TEMP RECOVERY... ESPECIALLY OVER THE WRN ZNS...WL BE NEGLIGIBLE. ALTHOUGH THE SURGE OF LLVL COLD AIR WL SUPPORT ONGOING LES...THE LO INVRN BASES ARND 3-4K FT AND ACYC NATURE OF THE H925 FLOW/GENERAL SUBSIDENCE WL LIMIT SN AMOUNTS...ESPECIALLY OVER THE W WHERE THE DGZ WL DESCEND INTO THE GROUND AND LIMIT SN GROWTH. THERE MAY BE AN UPTICK IN THE LES IN THE NW WIND SN BELTS E OF MQT LATER IN THE DAY HOWEVER AS LLVL CNVGC ON LK INDUCED TROF SHARPENS UNDER DEEPENING UPR TROF. AS FOR GOING WIND CHILL HEADLINES...OPTED TO DROP BARAGA...MARQUETTE AND DICKINSON COUNTIES FM THE HEADLINE GIVEN CURRENT CONDITIONS AND EXPECTATION THAT THESE AREAS WL NOT MEET CRITERIA MOST OF THE THE DAY. TONIGHT...THE LO TO THE SE IS PROGGED TO DEEPEN SGNFTLY AND LIFT NEWD INTO SE CANADA AS THE CENTRAL CONUS TROF SHARPENS WITH MORE PHASING OF THE ARCTIC AND POLAR BRANCHES. THE CORE OF THE COLDEST AIR...WITH H85 TEMPS DOWN TO -33C TO -35C...IS PROGGED TO SHIFT OVER WI. AS THE LO DEEPENS...THE PRES GRADIENT WL SHARPEN FURTHER OVER THE UPR LKS...ALLOWING H925 NW WINDS TO INCRS TO 25 TO 30 KTS. THE STRENGTHENING WINDS AND FALLING TEMPS SUPPORT GOING WIND CHILL WRNGS AWAY FM THE LK MODERATION THAT WL IMPACT MAINLY THE ERN CWA EVEN THOUGH A MORE N WIND COMPONENT OFF LK SUP MIGHT NOT ALLOW TEMPS TO FALL AS LO AS PREVIOUS FCST. BUT OVER THE ERN CWA...THE ARRIVAL OF DEEPER MSTR ASSOCIATED WITH ARRIVAL OF DEEP LYR QVECTOR CNVGC UNDER THE FALLING HGTS ASSOCIATED WITH THE DEEPENING UPR TROF AS WELL AS INCRSG LLVL CNVGC ACCOMPANYING THE SHARPENING OF THE LK INDUCED SFC TROF WL GIVE A BOOST TO THE LES. WITH MORE FVRBL SN GROWTH...H85 TEMPS ARE PROGGED TO FALL TO ARND -24C HERE BY 12Z MON...AS WELL AS INCRSG BLSN...OPTED TO REPLACE THE WIND CHILL ADVY FOR ALGER/LUCE/ SCHOOLCRAFT COUNTIES WITH A LK EFFECT SN ADVY TO ACCOUNT FOR SN FALL AT LEAST APRCHG ADVY AMOUNTS...BLSN AND WIND CHILLS AT LEAST APRCHG ADVY CRITERIA. .LONG TERM...(MONDAY THROUGH SATURDAY) ISSUED AT 448 AM EST SUN JAN 5 2014 THE MAIN CONCERN FOR THE LONG TERM FORECAST WILL BE EXTREMELY COLD TEMPERATURES/WIND CHILLS AND REDUCED VISIBILITIES FROM LAKE EFFECT SNOW SHOWERS AND BLOWING SNOW. LOW PRESSURE TRAVELING FROM THE OHIO VALLEY TODAY WILL REACH QUEBEC BY MONDAY MORNING. MEANWHILE...A COLD ARCTIC AIRMASS/HIGH PRESSURE WILL SINK FROM THE CANADIAN PRAIRIE INTO THE MIDWEST AND CENTRAL PLAINS. AS THIS HIGH SINKS TOWARDS THE GULF COAST MONDAY NIGHT...THE LOW OVER QUEBEC WILL DRIFT WESTWARD INTO JAMES BAY. THIS PATTERN WILL KEEP UPPER MICHIGAN IN A MODERATE WEST-NORTHWESTERLY FLOW THROUGH WEDNESDAY...AS A TIGHTER PRESSURE GRADIENT SITS OVER THE AREA. ADDITIONALLY...A 500MB LOW WILL CENTER ITSELF OVER UPPER MI MONDAY MORNING...THEN DRIFT SLOWLY NORTHEASTWARD INTO ONTARIO AND QUEBEC. WITH THE LOW CENTERED OVER UPPER MI 850-500MB QVECTOR CONVERGENCE IS MAXIMIZED OVER THE EASTERN U.P. AND LOWER MI. WITH NORTHWESTERLY WINDS MOVING THE COLD ARCTIC AIR OVER LAKE SUPERIOR...KEPT POPS IN NORTHWEST WIND FAVORED SNOWBELTS. ALSO INCREASED POPS IN THE EASTERN CWA AS THE UPPER LEVEL SUPPORT CROSSES THROUGH THE AREA WITH THE TROUGH. WINDS GENERALLY REMAIN NORTHWESTERLY THROUGH MONDAY AFTERNOON...THEN BEGIN TO BACK TOWARDS THE WEST-NORTHWEST WIND DIRECTION. ADJUSTED POPS ACCORDINGLY...WITH THE MAIN CORE OF PRECIPITATION IN THE EASTERN U.P. SHIFTING TO AREAS FAVORED BY WNW WINDS...MAINLY EAST OF MUNISING. ON TUESDAY SEVERAL SMALL SHORTWAVES SNEAK ALONG THE BASE OF THE TROUGH ALOFT AS IT MOVES EASTWARD...AND WNW WINDS BECOME MORE WESTERLY TOWARDS THE EVENING. MOST OF THE SNOW BY LATE TUESDAY AFTERNOON WILL BE OVER THE KEWEENAW AND EAST OF GRAND MARAIS. LIMITING FACTORS TO SIGNIFICANT ACCUMULATIONS WILL BE THE EXTREMELY COLD/DRY AIRMASS. THIS SENDS THE DGZ CRASHING INTO THE GROUND FOR MOST LOCATIONS...ESPECIALLY MONDAY NIGHT INTO TUESDAY AFTERNOON. AS A RESULT SNOW RATIOS WILL BE ON THE ORDER OF 15-18:1 AND FLAKES VERY FINE. AS FAR AS MOISTURE GOES...PWATS DURING THIS TIME FRAME DROP TO NEAR 15 PERCENT OF NORMAL FOR UPPER MI. OVERALL...FROM MONDAY MORNING THROUGH TUESDAY MORNING...HAVE 2-4 INCHES FOR AREAS FAVORED BY WEST-NORTHWEST WINDS. TUESDAY MORNING INTO WED MORNING ONLY HAVE 1-3 INCHES FOR THE SAME AREAS...MAINLY THE KEWEENAW AND EAST OF MUNISING NEAR LAKE SUPERIOR. THE COLD ARCTIC AIRMASS WILL BRING LOW TEMPERATURES CRASHING DOWN TO -27F OUT WEST...AND THE TEENS BELOW ZERO EAST FOR MONDAY NIGHT. AREAS NEAR THE LAKE WILL SEE TEMPERATURES DROP DOWN TO THE SINGLE DIGITS BELOW ZERO FARTHER EAST AND OVER THE KEWEENAW. WITH THE STRONGER WINDS OVER THE AREA HOWEVER...WIND CHILLS WILL DROP AS LOW AS -50F ACROSS THE WEST...AND MAINLY THE -30S AND -40S ELSEWHERE...EVEN NEAR THE LAKE. THOUGH SNOW ACCUMULATIONS WILL NOT BE HAZARDOUS BY THEMSELVES...THE COMBINATION OF SNOW...BLOWING SNOW...AND DANGEROUSLY LOW TEMPERATURES/WIND CHILLS WARRANT A LAKE EFFECT SNOW ADVISORY FOR AREAS IN THE EAST...MAINLY FOR ALGER/LUCE/SCHOOLCRAFT COUNTIES. WIND CHILLS WILL REACH ADVISORY CRITERIA...AND THE COMBINATION OF SNOW AND BLOWING SNOW/DUE TO WINDS AROUND 30 MPH/ WILL REDUCE VISIBILITIES DRAMATICALLY...ESPECIALLY WITH THE FINER FLAKES. ELSEWHERE...HAVE ONLY THE WIND CHILL WARNING IN EFFECT FOR THE MONDAY-TUESDAY TIME FRAME. THE KEWEENAW WILL ALSO SEE STRONG WINDS...GUSTING TO 25 TO 30 MPH...AND PERSISTENT LAKE EFFECT SNOW WITH AREAS OF BLOWING SNOW DURING THE MONDAY-TUESDAY TIME FRAME. HAVE INCLUDED THIS WORDING IN THE WIND CHILL WARNING FOR THE KEWEENAW/HOUGHTON COUNTIES FOR SIMPLICITY WITH HEADLINES. WINDS WILL GRADUALLY DIE DOWN FROM WEDNESDAY INTO THURSDAY AS THE HIGH CENTERS ITSELF OVER THE GREAT LAKES. LIGHT AND VARIABLE WINDS WILL GRADUALLY TRANSITION TO MORE MODERATE SOUTH TO SOUTHWESTERLY WINDS AS THE HIGH SHIFTS EASTWARD TOWARDS THE NEW ENGLAND STATES...AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA. SOME OF THE MODELS ATTEMPT TO BRING A WEAK SHORTWAVE TROUGH INTO THE MIDWEST LATE FRIDAY AFTERNOON AND SATURDAY...BUT OTHERS KEEP MORE ZONAL FLOW OVER THE AREA. WILL KEEP THE CONSENSUS POPS DURING THIS TIME FRAME HOWEVER...WITH THE WNW-LAKE EFFECT MOVING OUT INTO THE LAKE AS WINDS BACK TO THE SOUTH-SOUTHWEST. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1217 PM EST SUN JAN 5 2014 WITH EXTREMELY COLD AIR FLOWING INTO THE UPPER LAKES OVER THE NEXT COUPLE OF DAYS...LAKE EFFECT SNOW SHOWERS WILL BE THE RULE OFF LAKE SUPERIOR IN AN OVERALL NW FLOW. WITH MIXED LAYER WINDS TENDING TO VEER SLIGHTLY...-SHSN WILL BECOME INCREASINGLY PERSISTENT AT KIWD. EXPECT A TREND TO PREVAILING IFR CONDITIONS THIS AFTN/EVENING. WITH VERY COLD AIR MASS LEADING TO SMALL SNOWFLAKES THAT ARE HIGHLY EFFECTIVE AT REDUCING VIS...IT`S CERTAINLY POSSIBLE KIWD MAY FALL INTO A PREVAILING LIFR CONDITION. KCMX WILL REMAIN UNDER CONSTANT LAKE EFFECT SNOW SHOWERS. DURING THE AFTN...EXPECT CONDITIONS TO VARY BTWN LIFR AND IFR. AS SNOWFLAKES BECOME SMALLER AND WINDS INCREASE LEADING TO BLSN...PREVAILING LIFR CONDITIONS WILL TAKE OVER TONIGHT. AT SOME POINT...MOST LIKELY BY DAYBREAK...EXPECT CONDITIONS TO BECOME PREVAILING VLIFR AT KCMX. CONDITIONS COULD THEN CERTAINLY REMAIN VLIFR NEARLY CONTINUOUSLY THRU AT LEAST TUE MORNING. AT KSAW...INITIALLY DRY AIR AND DOWNSLOPE NW FLOW WILL RESULT IN VFR CONDITIONS FOR THE NEXT FEW HRS. LAKE EFFECT CLOUDS WILL ARRIVE LATER THIS AFTN AS THE FLOW VEERS SLIGHTLY AND ALLOWS MORE LAKE SUPERIOR MODIFIED...MOISTER AIR TO ARRIVE. ALTHOUGH THE LOW-LEVEL NW WINDS WILL NOT BE IDEAL...THE ARRIVAL OF DEEPER MOISTURE WILL RESULT IN -SHSN TONIGHT/MON MORNING ALONG WITH MORE SOLID MVFR CONDITIONS. && .MARINE...(FOR THE 4 AM LAKE SUPERIOR FORECAST ISSUANCE) ISSUED AT 448 AM EST SUN JAN 5 2014 A GALE WATCH IS IN EFFECT FOR CENTRAL AND EASTERN LAKE SUPERIOR MONDAY MORNING THROUGH TUESDAY NIGHT...AND A HEAVY FREEZING SPRAY WARNING REMAINS IN EFFECT... EXPECT NW WINDS 20-25 KTS THIS MORNING TO INCREASE TO 25-30 KTS LATER TODAY AND TONIGHT AS THE PRES GRADIENT OVER THE UPPER GREAT LAKES SHARPENS TO THE NW OF A DEEPENING LO PRES MOVING NE THRU THE SE GREAT LAKES INTO SE CANADA. THERE MAY BE A FEW GALE FORCE GUSTS OVER PORTIONS OF THE E LAKE LATE TONIGHT AS WELL. WITH ARCTIC AIR PERSISTING OVER THE AREA...EXPECT PERIODS OF HEAVY FREEZING SPRAY... ESPECIALLY OVER THE E HALF WHERE WINDS WILL BE STRONGEST. LAKE SUPERIOR WILL BE CAUGHT THIS TIGHT PRESSURE GRADIENT BETWEEN STRONG ARCTIC HIGH PRESSURE OVER THE PLAINS AND STRONG LOW PRESSURE OVER QUEBEC MONDAY INTO TUESDAY. AS A RESULT...WEST NORTHWEST GALES TO 35 KNOTS WILL OCCUR OVER MAINLY CENTRAL AND EASTERN LAKE SUPERIOR ON MONDAY AFTERNOON...AND WEST NORTHWEST GALES TO 40 KNOTS WILL OCCUR ON TUESDAY AFTERNOON. WINDS ON WESTERN LAKE SUPERIOR WILL LARGELY REMAIN WEST-NORTHWEST AT 20 TO 30 KNOTS DURING THIS TIME. ADDITIONALLY...COLD ARCTIC AIR IN PLACE OVER LAKE SUPERIOR COMBINED WITH THE STRONG WINDS WILL LEAD TO HEAVY FREEZING SPRAY FOR ALL OF THE LAKE THROUGH WEDNESDAY MORNING. ON WEDNESDAY AND THURSDAY HIGH PRESSURE WILL MAKE ITS WAY NORTHWARD...CENTERING ITSELF OVER THE GREAT LAKES. AS A RESULT...GUSTY WEST NORTHWEST WINDS WILL DIE DOWN...EVENTUALLY BACKING SOUTHWEST AT LESS THAN 10 KNOTS BY THURSDAY. AS THE HIGH SHIFTS TO THE NEW ENGLAND STATES AND LOW PRESSURE MOVES INTO NORTHERN MANITOBA FRIDAY AFTERNOON AND SATURDAY...SOUTHWESTERLY WINDS WILL PICK UP TO 15 TO 25 KNOTS OVER ALL OF LAKE SUPERIOR. && .MQT WATCHES/WARNINGS/ADVISORIES... UPPER MICHIGAN... WIND CHILL WARNING FROM 7 PM EST /6 PM CST/ THIS EVENING TO 11 AM EST /10 AM CST/ TUESDAY FOR MIZ001>005-009>013-084. WIND CHILL ADVISORY UNTIL 7 PM EST /6 PM CST/ THIS EVENING FOR MIZ002-009-010-084. LAKE EFFECT SNOW ADVISORY FROM 7 PM THIS EVENING TO 7 PM EST MONDAY FOR MIZ006-007-014-085. WIND CHILL WARNING FROM 7 PM MONDAY TO 11 AM EST TUESDAY FOR MIZ006-007-014-085. LAKE SUPERIOR... HEAVY FREEZING SPRAY WARNING UNTIL 7 AM EST /6 AM CST/ WEDNESDAY FOR LSZ162-243>245-248>251-263>267. GALE WATCH FROM MONDAY MORNING THROUGH LATE TUESDAY NIGHT FOR LSZ243>245-264>266. LAKE MICHIGAN... NONE. && $$ SHORT TERM...KC LONG TERM...MCD AVIATION...ROLFSON MARINE...KC/MCD
AREA FORECAST DISCUSSION
NWS TWIN CITIES/CHANHASSEN MN
305 PM CST SUN JAN 5 2014 .SHORT TERM...(THIS EVENING THROUGH MONDAY) ISSUED AT 305 PM CST SUN JAN 5 2014 NORTHWEST WINDS HAVE INCREASED SUBSTANTIALLY ACROSS WEST CENTRAL THROUGH SOUTH CENTRAL MN THIS AFTERNOON WITH 20-25 KNOTS COMMON. THIS IS OCCURRING AS THE CORE OF THE ARCTIC AIR ARRIVES ALONG WITH THE PRESSURE GRADIENT TIGHTENING BETWEEN A LOW PRESSURE STORM SYSTEM MOVING THROUGH THE OHIO VALLEY AND A 1053MB HIGH OVER MONTANA. WEB CAMS ARE SHOWING BLOWING SNOW WITH 1 TO 2 MILE VISIBILITY IN THE AFOREMENTIONED AREAS. THE BLOWING SNOW WILL CONTINUE THROUGH THE EVENING ADDING ANOTHER ELEMENT OF DANGER TO THE ALREADY LOW WINDS CHILLS OF -40 TO -45 CURRENTLY IN PLACE. SATELLITE IMAGERY SHOWS SOME NICE CONVECTIVE ROLLS AS WELL IN THE MN RIVER VALLEY WITH THE RAP INDICATING LOW LEVEL LAPSE RATES EXCEEDING 8 DEG C/KM. LITTLE DEVIATION TO THE FORECAST LOWS/HIGHS FOR TONIGHT AND MONDAY AS THE CORE OF THE ARCTIC VORTEX SWINGS THROUGH. MUCH OF CENTRAL MN AND ALONG HIGHWAY 8 IN WEST CENTRAL WI EXPECTED TO REACH -30 TO -35 WITH -25 TO -30 OVER THE REMAINDER OF THE FA. HIGHS ON MONDAY PROGGED TO BE IN THE -13 TO -19 RANGE FROM SOUTH TO NORTH. WIND CHILL VALUES OVERNIGHT AND MONDAY MORNING FROM -50 TO -65 WITH -40 TO -50 FOR MONDAY AFTERNOON. .LONG TERM...(MONDAY NIGHT THROUGH SUNDAY) ISSUED AT 305 PM CST SUN JAN 5 2014 THE MAIN WX DISCUSSION IS THAT THE CORE OF THE COLDEST AIR WILL HAVE MOVED OUT OF THE REGION BY MONDAY NIGHT WITH ONLY RESIDUAL AFFECTS BASED ON WIND SPDS AND TEMPS STILL IN THE TEENS AND 20S BLW ZERO THRU TUESDAY MORNING. AS HIGH PRESSURE MOVES OVERHEAD TUESDAY NIGHT/WEDNESDAY...THE AFFECTS OF RADIATIONAL COOLING MAY AID IN SOME LOWER TEMPS THAN CURRENTLY FORECAST. BASED ON CURRENT MODEL TRENDS NEAR -20F IN THE NORTHERN CWA...TO THE SINGLE DIGITS BLW ZERO IN THE SOUTHERN CWA SEEMS REASONABLE AT THIS TIME. AFTER WEDNESDAY...THE JET STREAM WILL MOVE NORTH WITH A MORE ZONAL FLOW DEVELOPING BY THE END OF THE WEEK. THIS WILL LEAD TO MUCH WARMER TEMPS BY FRI/SAT/SUN WITH ABV NORMAL READINGS ALMOST LIKELY. MODELS ARE STILL HAVING TROUBLE HANDLING THE SPLIT FLOW REGIME. BASICALLY FOR OUR REGION IT MEANS THAT UNCERTAINTY EXISTS AS MODELS ARE TRYING TO HOLD ONTO THE SOUTHERN JET AS THE MOST ACTIVE WX IN THE NEXT 7 DAYS. CONFIDENCE WILL REMAIN LOW UNTIL MODELS HAVE A BETTER HANDLE ON THE SOUTHERN JET STREAM STORM SYSTEM THAT WILL AFFECT THE SOUTHERN U.S. NEXT WEEKEND. AS FOR OUR AREA...MAINLY DRY WX WILL CONTINUE WITH A MUCH ANTICIPATED WARMING TREND AT LEAST IN THE SHORT TERM AFTER WEDNESDAY. && .AVIATION...(FOR THE 18Z TAFS THROUGH 18Z MONDAY AFTERNOON) ISSUED AT 1149 AM CST SUN JAN 5 2014 THE CORE OF THE ARCTIC VORTEX IS PUSHING ACROSS THE DAKOTAS LATE THIS MORNING. A 3 TO 4 HOUR PERIOD OF MVFR CEILINGS AND IFR VSBYS IN -SN/BLSN WILL PRECEDE THIS FEATURE AS IT MOVES THROUGH THIS AFTERNOON AND EARLY EVENING. A CONCERN IS THAT BLOWING SNOW MAY BE WORSE THAN WHAT THE KAXN AND KRWF TAFS INDICATE. THE BELIEF IS THAT THE MELTING AND MIXED PRECIP THAT OCCURRED TWO NIGHTS AGO WILL AID IN KEEPING THINGS MORE IN THE 1 TO 2 MILE RANGE. STRONG NW WINDS WILL MOVE INTO THE WESTERN TAF SITES EARLY THIS AFTERNOON AND PUSH EAST THROUGH THE EVENING. SUSTAINED SPEEDS IN THE 20 TO 25 KNOT RANGE EXPECTED IN THE MN RIVER VALLEY WITH GUSTS REACHING INTO THE LOW 30 KNOT RANGE. SPEEDS A LITTLE LESS FOR THE EASTERN SITES LATE THIS AFTERNOON AND EVENING. ONCE THE TROUGH ALOFT PASSES...VFR CONDITIONS EXPECTED LATER THIS EVENING THROUGH MONDAY. KMSP...NW WINDS ARE ALREADY BEGINNING TO GUST LATE THIS MORNING AND WILL CONTINUE TO INCREASE DURING THE AFTERNOON AND EARLY EVENING HOURS. NW WINDS AROUND 20 KNOTS FOR THE LATE AFTERNOON AND EVENING WITH GUSTS REACHING 30 KNOTS. THIS COMBINED WITH THE COLD TEMPS WILL CAUSE WIND CHILL VALUES FROM -30 TO -40 FOR THOSE WORKING OUTDOORS. A PERIOD OF MVFR CEILINGS/VSBY IN -SN EXPECTED AS WELL DURING THE LATE AFTERNOON AND EARLY EVENING...MARKING THE ARRIVAL OF THE COLD AIR ALOFT. VFR CONDITIONS THEREAFTER WITH BRISK NW WINDS THROUGH MONDAY. /OUTLOOK FOR KMSP/ MON...VFR. NW WINDS 10-20 KT. TUE...VFR. W WINDS 5-10 KT. WED...VFR. WINDS NEAR CALM. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR MNZ041>045-047>070- 073>078-082>085-091>093. WI...WIND CHILL WARNING UNTIL NOON CST TUESDAY FOR WIZ014>016-023>028. && $$ SHORT TERM...RAH LONG TERM...JLT AVIATION...RAH
AREA FORECAST DISCUSSION
NWS GREENVILLE-SPARTANBURG SC
103 PM EST SUN JAN 5 2014 .SYNOPSIS... A VERY STRONG AND DEEP UPPER LEVEL TROUGH WILL SWING AN ARCTIC COLD FRONT OVER THE REGION EARLY MONDAY AND USHER IN RECORD LEVEL COLD TEMPERATURES FOR MONDAY NIGHT AND TUESDAY. THIS AIRMASS WILL SLOWLY WARM BACK TO NORMAL LEVELS BY THE END OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... 1000 AM UPDATE...FREEZING RAIN ADVISORY ALLOWED TO EXPIRE AS TEMPS...AS WELL AS WET BULB TEMPS...ARE ABOVE FREEZING. SOME LIGHT RAIN MAY FALL IN THE OLD ADVISORY AREA THRU MIDDAY. 915 AM UPDATE...A FEW PATCHES OF RAINFALL ARE SEEN ON RADAR AT THIS HOUR OVER THE PIEDMONT AND NC FOOTHILLS. MOIST UPGLIDE CONTINUES TO DRIVE THE PRECIP THOUGH CONVECTION IS PLAYING A SMALL ROLE AND PROVIDING LOCALIZED ENHANCEMENT. PROG SOUNDINGS DO SUGGEST LESS THAN 100 J OF CAPE ABOVE INVERSION. THUNDER STILL A LONG SHOT WITH PARCELS STRUGGLING TO REACH EVEN THE FREEZING LEVEL...BUT DID INCLUDE SOME SUB-SCHC THUNDER CHANCES TODAY IN REVISED POPS...WHICH ARE GENERALLY A BIT HIGHER THAN BEFORE. CONVECTION ALLOWING MODELS STILL FAVOR THE ERN PIEDMONT...BUT DO FEATURE SOME SPRINKLES FURTHER WEST. RAP AND 12Z NAM ARE MORE WIDESPREAD...INDICATING POPS ACRS THE AREA OF UPGLIDE UNTIL TRENDING DOWN IN THE WEST THIS AFTN AS FLOW TURNS MORE SWLY AND LESS WARM ADVECTIVE. I MAINTAINED A LULL IN THE CENTRAL PORTION OF THE CWFA BETWEEN THE DIMINISHING UPGLIDE AND STRENGTHENING FLOW AHEAD OF SYNOPTIC FORCING/FROPA TONIGHT. TEMPS WERE TOO WARM PER NEWEST GUIDANCE...INCLUDING HOURLY SHORT TERM MODELS...WHICH REFLECT THE PERSISTENT LOW STRATUS AND FOG TODAY. HIGHS WERE GENERALLY LOWERED 3-5 DEGREES. AS OF 300 AM...CURRENTLY UPGLIDE SHWRS/DRIZZLE CONTINUE TO EXPAND IN COVERAGE ACRS SC AND THE NC PIEDMONT. MEANWHILE...NUMEROUS TEMP SENSORS ARE HOVERING IN THE 30-32 DEG RANGE ACRS MUCH OF THE NC FOOTHILLS AND NW PIEDMONT. GIVEN THE STRONGER RADAR RETURNS HEADING TOWARD THE NC PIEDMONT...I PLAN TO EXPAND THE FREEZING RAIN ADVISORY TO INCLUDE THE REST OF THE NC FOOTHILLS....AND ALL THE NW PIEDMONT. I WILL HAVE IT GO TILL 15Z...THO TEMPS SHUD START WARMING ABV FREEZING BEFORE THEN. FOR TODAY...THE BAND OF MOIST UPGLIDE PRECIP SHUD SHIFT EAST OF THE AREA BY LATE MORNING...WHILE THE NEXT BAND OF PRECIP ASSOCIATED WITH APPROACHING ARCTIC COLD FRONT WILL STILL BE TO THE WEST. SO EXPECT A LULL IN -RA/DZ FOR THE AFTN. HOWEVER...CLOUDS SHUD PERSIST...SAVE FOR SOME OF THE BREAKS POSSIBLE IN SOME OF THE NC MTN VLYS DUE TO STRONG SWLY DOWNSLOPE FLOW. TEMPS APPEAR TRICKY...AS COLD POOL WILL LINGER EAST OF THE MTNS...BUT LACK OF PRECIP SHUD ALLOW SOME WARMING AIDED BY STRONG WAA. FOR NOW...FORECASTING TEMPS TO RISE INTO THE 40S AS THE DAY WEARS ON. TONIGHT...GUIDANCE HAS SLOWED DOWN TIMING OF STRONG ARCTIC FROPA SLIGHTLY...BRINGING IT THRU THE CWFA BETWEEN MIDNIGHT AND 6 AM MONDAY. A SWLY 50-60 KT LLJ WILL TRANSVERSE THE CWFA JUST AHEAD OF THE FRONT. SO A BRIEF PERIOD OF STRONG WIND GUSTS WILL BE POSSIBLE ALONG SOME OF THE RIDGES. HOWEVER...SHUD BE CONFINED IN AREA AND TOO BRIEF TO WARRANT ANY HEADLINE FOR IT ATTM. OTHERWISE...POPS RAMP UP TO LIKELY TO CATEGORICAL FOR A FEW HOURS OVERNIGHT. QPF LOOKS LIGHT...GENERALLY UNDER 0.25" FOR MOST AREAS...EXCEPT 0.25-0.5" ABOVE 3500 FT IN THE MTNS. SNOW LEVELS SHUD START TO FALL AROUND MIDNIGHT TO VALLEY FLOORS BY 6 AM. EVEN SOME CHANGEOVER MAY OCCUR IN THE NC FOOTHILLS BEFORE PRECIP TAPERS OFF. GIVEN A SLIGHTLY SLOWER TIMING OF THE CAA...SNOW ACCUMS LOOK TO BE CONFINED MOSTLY TO ABOVE 3500 FT UNTIL CLOSE TO DAYBREAK...WHEN IT WILL START ACCUMULATING IN THE VALLEYS. TEMPS ARE EXPECTED TO ALREADY BE IN THE TEENS TO MID 20S BY DAYBREAK IN THE MTNS. MEANWHILE...TEMPS WILL CONT TO RISE OR HOLD STEADY WITH STRONG WAA AHEAD OF THE FRONT ACRS THE SOUTHEAST CORNER OF THE CWFA...INCLUDING CHARLOTTE...WHERE SOME 50S MAY OCCUR BEFORE FROPA. THERE DOESN/T LOOK TO BE ENUF INSTBY OR FORCING FOR THUNDER. && .SHORT TERM /MONDAY THROUGH WEDNESDAY/... AS OF 330 AM SUNDAY...NOT MUCH CHANGE FROM EARLIER THINKING WITH REGARD TO THE IMPACTS ACROSS THE WESTERN CAROLINAS FROM THE PASSAGE OF AN ARCTIC COLD FRONT MONDAY MORNING...SO IT IS TIME TO ACT. STILL EXPECTING THE FRONT TO BE PUSHING EAST ACROSS THE PIEDMONT AT SUNRISE MONDAY. PRECIPITATION SHOULD HAVE ALREADY CHANGED TO SNOW ACROSS THE MTNS. E OF THE MTNS...LINGERING PRECIP COULD CHANGE OVER TO A BRIEF PERIOD OF SNOW SHOWERS OR FLURRIES BEFORE ENDING MID MORNING...AS COLD AIR MOVES IN BEHIND FRONT...BUT NO SIGNIFICANT ACCUM IS EXPECTED. TEMPS MAY FALL BRIEFLY...THEN STABILIZE OR RISE A FEW DEGREES DURING LATE MORNING...BUT THEN STRONG COLD ADVECTION WILL TAKE OVER AND TEMPS WILL FALL THROUGH THE AFTERNOON. SNOW PRODUCTION WILL CONTINUE NEAR THE TN BORDER THROUGHOUT MONDAY AS TEMPS FALL AND MOISTURE IS PUSHED UP THE W SIDE OF THE MTNS. THERE ARE SOME MIXED SIGNALS AS TO WHAT THE POTENTIAL FOR ACCUMULATION WILL BE. ON THE ONE HAND...THE MODELS FCST WEAK SFC BASED CAPE UPSTREAM...BUT THE SURFACE MIGHT BE FREEZING BY MONDAY AFTERNOON UPSTREAM...WHICH MIGHT CUT BACK ON MOISTURE FLUX FROM THE GROUND. THERE SHOULD BE SOME MID LEVEL FORCING IN THE AFTERNOON AS DPVA MOVES OVERHEAD...BUT THE 850MB WIND RETAINS A MORE WESTERLY COMPONENT...WHICH ALSO DOES NOT ALLOW FOR A GREAT LAKES CONNECTION. THESE MIGHT PROVE TO BE LIMITING FACTORS...SO THE POTENTIAL LOOKS TO BE SOMEWHERE IN THE NEIGHBORHOOD OF 3-5 INCHES ON MTN PEAKS AND 2 INCHES IN THE VALLEYS. GIVEN THAT NEIGHBORING OFFICES ARE GOING WITH A WARNING...THE BEST COURSE OF ACTION WILL BE TO ALSO GO WITH A WINTER STORM WARNING FOR THE COUNTIES ALONG THE TN BORDER STARTING AT MIDNIGHT AND RUNNING THROUGH 6 PM MONDAY. NOTE THAT ONLY THE RIDGETOPS ARE LIKELY TO REACH WARNING CRITERIA ACCUMULATION...WHILE THE VALLEYS WILL GET LESS SNOW...BUT THAT PERHAPS THE IMPACT OF BLOWING SNOW AND VERY COLD TEMPS MIGHT MAKE IT DANGEROUS ENOUGH THAT PUBLIC IMPACT JUSTIFIES THE WARNING. THE ARCTIC AIR REALLY TAKES HOLD MONDAY NIGHT AND TUESDAY. TEMPS WILL BE WELL BELOW NORMAL...LIKELY MORE THAN 20 DEGREES BELOW NORMAL. THE GUIDANCE CONTINUES TO TREND COOLER WITH EACH RUN...SO THE FCST LOWS ARE NOW SOLIDLY IN RECORD TERRITORY. WIND GUST POTENTIAL MAY PEAK MONDAY EVENING AS THE SHORT WAVE PASSES THROUGH. WIND CHILL VALUES WILL FALL THROUGH THE ADVISORY RANGE MONDAY AFTERNOON ACROSS THE MTNS...AND BELOW WARNING CRITERIA AROUND SUNSET MONDAY. FOR THAT REASON...A WIND CHILL WATCH WILL BE ISSUED FOR THE MTNS AND HIGH ELEVATION FOOTHILL ZONES FOR MONDAY NIGHT THROUGH NOON TUESDAY. VALUES MAY REACH ADVISORY CRITERIA OUTSIDE THE MTNS...SO AN ADVISORY MAY BE ISSUED LATER TODAY. ON TUESDAY...HIGH TEMPS WILL REMAIN IN THE TEENS TO LOWER 20S OVER THE MTNS. TEMPS WILL PROBABLY STAY BELOW FREEZING OUTSIDE OF THE MTNS...WHICH WOULD BE REMARKABLE WITH NO SNOW ON THE GROUND. GUIDANCE TEMPS WERE SLIGHTLY COOLER THAN THE PREV FCST ONCE AGAIN...AND THIS TREND WAS FOLLOWED. THE REST OF THE SHORT RANGE REMAINS QUIET. THE ARCTIC HIGH REMAINS IN CONTROL THROUGH WEDNESDAY...WITH THE AIR MASS SLOWLY MODIFYING. TEMPS WILL REMAIN RATHER COLD...ONLY NOT TO THE EXTREME WE WILL SEE MONDAY NIGHT AND TUESDAY. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... AS OF 300 AM EST SUNDAY...THE LATEST 00Z GFS/ECMWF AGREE THAT SWLY FLOW ALOFT WILL PERSIST ACROSS THE REGION WED NIGHT INTO THU...WITH A WEAK SOUTHERN STREAM UPPER SHORTWAVE PASSING OVERHEAD THU NIGHT INTO EARLY FRI. THE ECMWF DEVELOPS UPPER RIDGING ACROSS THE REGION FRI THRU EARLY SUN AS ANOTHER SOUTHERN STREAM UPPER SHORTWAVE TROUGH EJECTS OUT OF THE DESERT SW AND REACHES WESTERN GULF. MEANWHILE...THE FASTER GFS PUSHES THIS THROUGH INTO THE MISSISSIPPI VALLEY BY SAT NIGHT AND MAINTAINS SWLY FLOW ALOFT ACROSS THE REGION. AT THE SURFACE...MOIST RETURN FLOW WILL DEVELOP ACROSS THE REGION BY WED NIGHT AS HIGH PRESSURE SLIDES OFF THE MID ATLANTIC COAST. WITH INCREASING ISENTROPIC LIFT AND A PASSAGE OF UPPER SHORTWAVE ON THU...LIGHT PRECIP WILL DEVELOP ACROSS THE REGION BY EARLY THU AFTERNOON. PRECIP WILL BE MAINLY LIQUID THOUGH A BRIEF PERIOD OF FREEZING RAIN IS POSSIBLE AT THE ONSET OF PRECIP. THE ECMWF THEN DEVELOPS BROAD AREAS OF DRY HIGH PRESSURE ACROSS THE SE THU NIGHT INTO SAT...WHILE THE GFS KEEPS THE HIGH OFF THE ATLANTIC COAST AND SLOWLY PUSHES A COLD FRONT INTO THE TN VALLEY BY FRI NIGHT MAINTAINING DEEP SOUTHERLY FLOW ACROSS THE REGION. THE GFS SLOWLY PUSHES THE FRONT THROUGH THE REGION SAT NIGHT INTO SUN WITH A SERIES OF SURFACE WAVES RIDING ALONG THE FRONT. USING A COMPROMISE BETWEEN THE DRY ECMWF AND THE WET GFS...HAVE INHERITED SLIGHT CHANCE POPS ON FRI AND LOWERED POPS FROM THE HIGH END CHANCE/LIKELY TO THE 30/40 PERCENT RANGE ON SAT. THANKS TO WELL ABOVE FREEZING TEMPS...PRECIP WILL BE ALL LIQUID. TEMPS WILL START OUT AROUND 10-15 DEGREES BELOW NORMAL ON THU AND QUICKLY WARM BACK UP TO NEAR NORMAL BY FRI. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AT KCLT...LIFR STRATUS ALREADY IN PLACE OVER THE REGION STANDS LITTLE CHANCE OF IMPROVING THIS AFTN WITH CIRRUS DECK NOW SEEN MOVING ABOVE IT ON IR SATELLITE. FURTHERMORE AMPLIFYING WARM UPGLIDE WILL ONLY REINFORCE THE STRATUS GOING INTO THE EVENING...WITH SHOWER CHANCES INCREASING AFTER SUNSET AND PEAKING JUST PRIOR TO COLD FROPA JUST BEFORE DAYBREAK. LIFR CIGS WILL LAST UNTIL THE FROPA FOLLOWED BY RELATIVELY FAST IMPROVEMENT TO VFR. VERTICAL THERMAL PROFILES AND SFC TEMPS SUPPORT ALL RAIN...NO FZRA OR SN...WITH ARCTIC AIR NOT PUSHING IN UNTIL AFTER PRECIP TAPERS OFF. EXCEPTIONALLY STRONG LOW LEVEL JET WILL PRECEDE FRONT IN STRONG INVERSION OVER THE COOL SFC LAYER. WILL CARRY LLWS AS A RESULT TONIGHT. SLY OVERNIGHT WINDS TURN NW AND GUSTY BEHIND THE FRONT. ELSEWHERE...MAIN DIFFERENCES FROM KCLT ARE IN FRONTAL TIMING...APART FROM THE RA/SN CHANGEOVER OCCURRING IN THE MTNS AND FOOTHILLS. IFR TO LIFR CIGS ARE LIKELY TO HANG ON AT MID-AFTERNOON LEVELS THRU MOST OF TONIGHT. AS AT KCLT COLD AIR ARRIVES TOO LATE TO AFFECT PTYPE. IN FACT...IGNORING KAVL...ANY SN WOULD BE VERY BRIEF AND UNWORTHY OF TAF MENTION. AT KAVL AND ELSEWHERE IN THE MTNS THE SNOW WILL BE PARTLY DUE TO UPSLOPE EFFECTS AND ACCUMULATION WILL MAINLY OCCUR NEAR THE TENN BORDER. MVFR TO IFR VSBY COULD RESULT FROM ANY SNOW HOWEVER. LLWS CARRIED AT ALL TERMINALS. WIND GUSTS POST FROPA WILL BE MODEST AT BEST AT THE TAF SITES...HOWEVER STRONG GUSTS OF 30-40 KT LIKELY THRU 18Z IN HIGH TERRAIN. OUTLOOK...NORTHWEST FLOW SNOW WILL CONTINUE IN THE MTNS MONDAY CAUSING SOME PERIODIC RESTRICTIONS NEAR THE TENN BORDER. VERY COLD AND DRY HIGH PRES SETTLES IN FOR TUESDAY AND WEDNESDAY. WINTRY PRECIP MAY RETURN TO THE AREA WITH ANOTHER SYSTEM MOVING THRU THE ERN US LATE IN THE WEEK. CONFIDENCE TABLE... 18-24Z 00-06Z 06-12Z 12-18Z KCLT MED 78% HIGH 91% HIGH 84% HIGH 83% KGSP MED 75% HIGH 90% MED 76% HIGH 89% KAVL MED 73% HIGH 88% MED 77% HIGH 83% KHKY MED 78% HIGH 96% MED 76% HIGH 83% KGMU MED 75% HIGH 91% MED 75% HIGH 89% KAND MED 75% HIGH 86% MED 73% HIGH 83% THE PERCENTAGE REFLECTS THE NUMBER OF GUIDANCE MEMBERS AGREEING WITH THE SCHEDULED TAF ISSUANCE FLIGHT RULE CATEGORY. COMPLETE HOURLY EXPERIMENTAL AVIATION FORECAST CONSISTENCY TABLES AND ENSEMBLE FORECASTS ARE AVAILABLE AT THE FOLLOWING LINK: (MUST BE LOWER CASE) WWW.WEATHER.GOV/GSP/AVIATION_TABLES && .CLIMATE... RECORD LOW MINIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL... 3 IN 1879 CLT...12 IN 1884 GSP... 9 IN 1904 RECORD LOW MAXIMUM TEMPERATURES FOR TUESDAY JAN 7TH... AVL...21 IN 1988 CLT...24 IN 1988 GSP...27 IN 1988 && .GSP WATCHES/WARNINGS/ADVISORIES... GA...NONE. NC...WIND CHILL WATCH FROM MONDAY EVENING THROUGH TUESDAY MORNING FOR NCZ033-048>053-058-059-062>065-501-503-505-507-509. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 6 PM EST MONDAY FOR NCZ033-048>052-058. SC...NONE. && $$ SYNOPSIS...JOH NEAR TERM...ARK/WIMBERLEY SHORT TERM...PM LONG TERM...JOH AVIATION...WIMBERLEY CLIMATE...ARK/PM
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
110 PM EST SUN JAN 5 2014 .SYNOPSIS... A WARM FRONT WILL APPROACH THE AREA FROM THE SOUTH TODAY... SPREADING LIGHT RAIN ACROSS THE AREA MAINLY EAST OF THE BLUE RIDGE. AN ARCTIC FRONT WILL ARRIVE LATE TONIGHT. ITS PASSAGE WILL BRING SOME VERY COLD AIR TO OUR REGION WITH DANGEROUS WIND CHILLS. THIS AIRMASS WILL LAST INTO TUESDAY...THEN SLOWLY MODERATE FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1205 PM EST SUNDAY... CANCELLED THE FREEZING RAIN ADVISORY AS ALL TEMPERATURES FROM REPORTING SITES HAVE RISEN TO ABOVE FREEZING...EXCEPT FOR A FEW LOCATIONS WEST OF THE AREA OF LIGHT PRECIP THAT ARE RIGHT AT FREEZING. ADJUSTED SOME HIGH TEMPS DOWN A BIT WITH WEAK WEDGE CONTINUING ACROSS NORTHEAST PORTION OF THE AREA. ADJUSTED SOME MAX TEMPS UPWARD IN FAR SOUTHWEST GIVEN CURRENT TEMPS. MINOR CHANGES TO POPS REMAINDER OF AFTERNOON WITH HRRR AND RAP DOING BEST WITH CURRENT AREA OF LIGHT RAIN AND HAVE TRIED TO INDICATE A ZONE OF HIGHEST POPS CONTINUING JUST EAST OF BLUE RIDGE WITH LOWER POPS FARTHER EAST BORDERING WAKEFIELD FCST AREA...AT LEAST UNTIL LATE AFTERNOON BEFORE THIS ZONE FINALLY SHIFT EAST AND NORTH OUT OF THE FCST AREA BY EARLY EVENING. PREV DISCUSSION AS OF 1025 AM EST SUNDAY... UPDATED TO CANCEL FREEZING RAIN ADV FOR MTNS OF NW NC AND UP THE BLUE RIDGE TO FLOYD WHERE HIGHER ELEVATIONS ARE WELL ABOVE FREEZING. STILL POCKETS OF SUB FREEZING TEMPS IN PARTS OF NEW RIVER VALLEY WITH SOME GROUND TEMPS LIKELY TO STILL BE BELOW FREEZING...AND THEN NORTHWARD INTO ROANOAKE VALLEY AND MUCH OF FOOTHILLS AND PIEDMONT STILL HAVE POCKETS OF SUB FREEZING TEMPS. THUS WILL KEEP THE ADVISORY GOING UNTIL NOON IN THOSE LOCATIONS. MOST OF PRECIP HAS MOVED EAST OF BLUE RIDGE...BUT DRIZZLE STILL POSSIBLE AND ONGOING SLICK SPOTS UNTIL ALL TEMPS HAVE RISEN ABOVE FREEZING. PREVIOUS DISCUSSION AS OF 830 AM EST SUNDAY... NUMEROUS CALLS COMING INTO THE OFFICE THIS MORNING OF AUTO ACCIDENTS CAUSED BY SLICK ROADS EAST OF THE BLUE RIDGE. GROUND TEMPERATURES IN MANY AREAS WERE SIGNIFICANTLY CHILLED DURING THE POLAR SURGE A COUPLE DAYS AGO...AND WITH AIR TEMPERATURES ACROSS THE PIEDMONT HOVERING AROUND FREEZING...GIVE OR TAKE A DEGREE... EXPECT ICING TO CONTINUE FOR THE NEXT FEW HOURS. EVEN AFTER AIR TEMPERATURES WARM LATER THIS MORNING...EXPECT ICING ON THE GROUND TO BE SLOW TO MELT. MOTORISTS SHOULD EXERCISE EXTREME CAUTION WHEN TRAVELING THIS MORNING AS THE ICING WILL BE VERY DIFFICULT TO SEE UNTIL THEY ARE ALREADY DRIVING ON IT. TO MAKE MATTERS WORSE... SURFACE OBSERVATIONS ACROSS THE MOUNTAINS INDICATE VISIBILITIES FOGGING DOWN AS MOIST AIR CONTINUES TO WORK IN FROM THE SOUTHWEST. EXPECT THESE CONDITIONS TO BE SLOW TO IMPROVE THROUGH THE DAY. WAVES OF LIGHT RAIN WILL PASS ACROSS THE REGION THROUGH THE DAY AS MINOR DISTURBANCES EMBEDDED IN THE SOUTHWESTERLY FLOW ALOFT MOVE ACROSS THE CENTRAL APPALACHIAN CHAIN. BELIEVE THAT THE LIGHT RAIN WILL LIMIT HEATING ACROSS THE EAST AND HAVE THEREFORE HELD HIGHS A LITTLE BELOW GUIDANCE...NAMELY THE UPPER 30S AND THE LOW 40S. RAINFALL WILL NOT BE AS WIDESPREAD ACROSS THE MOUNTAINS...AND EXPECT TO SEE MID AND UPPER 40S THIS AFTERNOON. ALL OF THIS WARM AIR IS FLOWING IN AHEAD OF OUR NEXT STRONG COLD FRONT...EXPECTED TO ENTER THE REGION SHORTLY AFTER MIDNIGHT. THE FRONT WILL SHIFT EAST VERY RAPIDLY...EXITING OUR AREA BEFORE SUNRISE. WITH PRECIPITABLE WATER VALUES RISING TO AROUND AN INCH BY MIDNIGHT...BELIEVE ALL LOCATIONS WILL SEE A BRIEF SHOT RAIN AS THE FRONT PASSES. RAIN WILL CHANGE VERY RAPIDLY TO SNOW AS TEMPERATURES DROP BEHIND THE FRONT...WITH SNOW ACCUMULATING ACROSS THE WESTERN RIDGES THROUGH THE NIGHT. THE GREATEST IMPACTS OF THE COLD FRONT WILL BE FELT ALONG THE WESTERN MOST COUNTIES FROM GREENBRIER TO WATAUGA. HIGHEST SNOWFALL ACCUMULATIONS WILL OCCUR IN WESTERN GREENBRIER AND NORTHERN SUMMERS COUNTIES...WHERE LOCALLY 6 TO 9 INCHES ARE POSSIBLE THROUGH MONDAY MORNING. LESSER AMOUNTS OF 2 TO LOCALLY 5 INCHES ARE POSSIBLE ACROSS THE WEST FACING SLOPES IN THE MOUNTAIN EMPIRE AND NORTHERN NORTH CAROLINA. GUSTY WINDS BEHIND THE FRONT WILL RESULT IN BLOWING SNOW AND POSSIBLY WHITE OUT CONDITIONS THAT MAY PERSIST INTO THE MONDAY MORNING COMMUTE. IN ADDITION...THE COLD AIR WILL LIKELY RESULT IN FLASH FREEZING OF WET SURFACES FROM RAINFALL EARLIER IN THE EVENING...MAKING FOR SLICK ROADWAYS. AS A RESULT...HAVE ISSUED A WINTER STORM WARNING FOR OUR WESTERN MOST COUNTIES...AND A WIND ADVISORY FOR ALL OF OUR MOUNTAIN COUNTIES...BEGINNING AT MIDNIGHT TONIGHT. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 545 AM EST SATURDAY... BY THE BEGINNING OF THIS PERIOD WE WILL BE FIRMLY ENTRENCHED IN THE THRAWLS OF AN INTENSE ARCTIC AIR MASS THAT PROMISES TO BRING SOME OF THE COLDEST TEMPERATURES IN A COUPLE OF DECADES ALONG WITH DANGEROUSLY COLD WIND CHILLS. ALTHOUGH THE BULK OF SYNOPTICALLY DRIVEN PCPN WILL BE ENDING DURING THIS TIME FRAME...UPSLOPE SNOW SHOWERS WILL MOST CERTAINLY CONTINUE GIVEN STRENGTH OF CAA. IN FACT...FEELS MODELS ARE WAY TO QUICK IN ENDING SHSN...AND HAVE EXTENDED WELL BEYOND THE MODEL INDICATIONS OF 18Z MON...ALL THE WAY TO EARLY TUESDAY MORNING. GRANTED...THE MOST SIGNIFICANT SNOWFALL WILL END BY 18Z MON...BUT EXPECT SHSN TO CONTINUE IN EARNEST ALONG WEST FACING SLOPES WITH ADDITIONAL ACCUMULATIONS OF ANOTHER INCH OR TWO POSSIBLE IN THIS TIME FRAME. THUS...THE SNOW PORTION OF THE WINTER STORM WARNING WILL REMAIN IN EFFECT UNTIL 00Z TUE. WIND CHILL WILL PERHAPS BE THE MOST SIGNIFICANT ISSUE WITH THIS EVENT...WITH DANGEROUSLY COLD -20 TO -40F WIND CHILLS IN PLACE OVERNIGHT MONDAY INTO THE FIRST HALF OF THE DAY TUE. HAVE UPGRADED THE WIND CHILL WATCH TO A WIND CHILL WARNING WITH THIS PACKAGE AND ALSO INCLUDED A WIND CHILL ADVISORY FOR THE REMAINDER OF THE CWA...GENERALLY EAST OF I-81 AND I-77...PRINCIPALLY THE PIEDMONT. SUSTAINED WINDS SHOULD REMAIN MOSTLY IN THE 15 TO 30 MPH RANGE LATE TONIGHT THROUGH EARLY TUE...BUT GUSTS OF 45 TO 50 MPH CAN BE EXPECTED IN THE HIGHER ELEVATIONS OF THE ALLEGHANYS AND BLUE RIDGE. THIS SPEEDS DO NOT MEET HIGH WIND WARNING CRITERIA...SO HAVE SIMPLY GONE WITH A WIND ADVISORY AT THIS POINT. A STRONG NON-DIURNAL TEMPERATURE TREND IS EXPECTED MON...WITH TEMPERATURES CONTINUING TO PLUNGE UNTIL EARLY TUE. BY TUE MORNING...THE WESTERN PARTS OF THE CWA WILL BE WELL BELOW ZERO...WITH -20F POSSIBLE IN NW GREENBRIER EARLY TUE...GENERALLY 0 TO -10F ELSEWHERE THROUGH THE ALLEGHANYS TO THE SINGLE DIGITS ACROSS THE PIEDMONT. HAVE FAVORED THE COLDER ECMWF MOS FOR MINS THROUGH THE PERIOD WITH THE COLDER MEX MOS FOR MAXS THROUGH THE PERIOD. THE ARCTIC HIGH WILL BE CENTERED RIGHT OVER THE CWA AT 12Z WED...SO ONLY A SLOW MODERATION IN TEMPERATURES ARE EXPECTED WED AS THE -30C AIR AT 850MB FINALLY LIFTS OUT OF THE CWA. && .LONG TERM /THURSDAY THROUGH SUNDAY/... AS OF 200 PM EST SATURDAY... DURING THIS PORTION OF THE FORECAST...THE WEATHER PATTERN ACROSS OUR REGION WILL TRANSITION TO ONE DOMINATED MORE BY THE SOUTHERN STREAM OF THE JET STREAM RATHER THAN THE NORTHERN STREAM. WITHIN THIS PATTERN WILL BE A SERIES OF FAST MOVING DISTURBANCES...EACH WITH THE POTENTIAL TO BRING SOME LIGHT PRECIPITATION TO PARTS OR ALL OF THE FORECAST AREA. SPECIFICALLY...WE ARE EXPECTING A SYSTEM THURSDAY AFTERNOON AND THURSDAY NIGHT TO IMPACT MAINLY THE WESTERN PARTS OF THE REGION. ONE FRIDAY INTO FRIDAY NIGHT MAY SKIRT THE FAR WESTERN PART OF THE REGION. FINALLY...ONE LATE FRIDAY NIGHT THROUGH SATURDAY HAS THE POTENTIAL OF BRINING RAIN TO ALL OF THE REGION. EACH DAY...TEMPERATURES WILL TREND MILDER SO THAT BY SATURDAY HIGH TEMPERATURES ARE FORECAST IN THE LOWER 50S ACROSS THE MOUNTAINS WITH MID TO UPPER 50S ACROSS THE PIEDMONT. MOST OF THE PRECIPITATION ASSOCIATED WITH THE DISTURBANCES WILL BE IN THE FORM OF RAIN. ENOUGH COLD AIR WILL STILL BE AROUND THURSDAY NIGHT INTO FRIDAY FOR SOME POCKETS OF FREEZING RAIN. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 105 PM EST SUNDAY... THIS AFTERNOON THE FCST AREA REMAINS IN A SHALLOW WEDGE AND MOIST AIRMASS JUST NORTH OF SFC WARM FRONT...WITH AREAS OF LIGHT RAIN PERSISTING MAINLY EAST OF BCB/ROA...ALTHOUGH CANT RULE OUT A SPRINKLE OR BRIEF PERIOD OF DRIZZLE THERE AS WELL. MAIN STORY FOR ALL AIRPORTS IS IFR CIGS AND FOR DAN AND LYH WITH BEST CHC FOR LIGHT RAIN...EVEN LIFR CIFS AND VSBYS THROUGH REST OF AFTERNOON AT THOSE TWO AIRPORTS. CHC FOR SOME VFR CIGS AT LWB AND BLF THIS AFTERNOON..BUT BLV PREVAILING WILL BE IFR CIGS REMAINDER OF DAY. IFR CONDITIONS MAY NOT BREAK AT ALL FOR BCB/ROA/LYH/DAN BEFORE COLD FRONT ARRIVES LATE TONIGHT. THE COLD FRONT WILL ENTER THE REGION BETWEEN 07 UTC AND 10 UTC TONIGHT. A FEW SCATTERED SHOWERS ALONG AND AHEAD OF THE FRONT WILL QUICKLY TRANSITION TO SNOW AFTER THE FRONT PASSES...WITH REDUCED VSBYS IN SNOW MAINLY AT BLF...WITH BRIEFLY LOWER VSBYS AT BCB AND LWB. VERY COLD AIR WILL ARRIVE BEHIND THE FRONT...WHICH COULD CAUSE FLASH FREEZING OF WET SURFACES FROM RAINFALL EARLIER IN THE EVENING. WHILE SNOW SHOWERS WILL NOT PERSIST AS LONG FOR ROA DAN AND LYH. EXPECT THE CHANGE OVER TO SNOW AROUND 06/08Z AT BLF AND LWB...06/09Z FOR BCB AND ROA...AND 06/10Z FOR LYH AND DAN. ACCUMULATIONS OF AROUND 4 INCHES ARE POSSIBLE FOR BLF...AN INCH OR TWO AT LWB...AND LESS THAN AN INCH FOR ROA AND BCB. STRONG WINDS FROM THE NORTHWEST WILL ACCOMPANY THE FRONT...WITH OCCASIONAL 35 TO 40 KT GUSTS EXPECTED ACROSS THE MOUNTAINS. STRONG CROSS- BARRIER FLOW WILL ALSO RESULT IN MODERATE TURBULENCE. IFR CONDITIONS MAY PERSIST THROUGH THE DAY MONDAY AT BLF IN SNOW SHOWERS. ELSEWHERE...VFR CIGS AND VSBYS WILL RETURN DURING THE DAY MONDAY...BUT WITH CONTINUED STRONG AND GUSTY NW WINDS. WHILE WINDS WILL DIMINISH SOMEWHAT ON MONDAY AFTERNOON...A SECONDARY SHOT OF ARCTIC AIR WILL ARRIVE MONDAY NIGHT...CAUSING WIND SPEEDS TO INCREASE ONCE AGAIN. THIS ARCTIC AIR WILL CAUSE TEMPERATURES TO FALL INTO THE POSITIVE SINGLE DIGITS EAST OF THE BLUE RIDGE...AND FALL BELOW ZERO TO THE WEST. SNOW SHOWERS WILL PERSIST ACROSS THE MOUNTAINS THROUGH TUESDAY MORNING...BEFORE HIGH PRESSURE SETTLES IN...CAUSING WIND SPEEDS AND SNOW SHOWERS TO DECREASE. HIGH PRESSURE WILL RETURN BY TUES NIGHT AND WEDNESDAY WITH VFR CONDITIONS AND MILDER TEMPERATURES...WITH THE NEXT WEATHER SYSTEM EXPECTED BY LATE IN THE WEEK. && .CLIMATE... AS OF 220 PM EST THURSDAY... FORECAST LOW TEMPERATURES MONDAY NIGHT...EARLY JAN 7...ARE FORECAST TO BE AROUND ZERO OR A BIT BELOW ZERO ACROSS THE MOUNTAINS AND IN THE SINGLE DIGITS TO NEAR 15 ACROSS THE PIEDMONT. OF OUR CLIMATE SITES...ALL BUT DANVILLE IS FORECAST TO BREAK THE RECORD. HIGH TEMPERATURES ON TUESDAY JANUARY 7 ARE FORECAST TO BE IN THE TEENS ACROSS THE MOUNTAINS AND LOW TO MID 20S ACROSS THE PIEDMONT. OUR CURRENT FORECAST PLACES THE RECORD MINIMUM HIGH TEMPERATURE RECORDS IN JEOPARDY AT BOTH BLACKSBURG AND LEWISBURG WHILE THE OTHER LOCATION WILL SEE TEMPERATURES WITHIN A FEW DEGREES OF THE RECORDS. JANUARY 7 RECORDS LOWS MINIMUM HIGHS BLACKSBURG VA... 1/1988 19/1988 BLUEFIELD WV.... 0/1970 11/1988 DANVILLE VA..... 10/1969 26/1988 ROANOKE VA...... 8/1970 17/1988 LEWISBURG WV.... 7/2004 11/1988 LYNCHBURG VA.... 10/1912 17/1988 && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR VAZ007-009>020-022>024. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR VAZ007-009>020-022>024. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR VAZ007-009-015. WIND CHILL ADVISORY FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR VAZ032>035-043>047-058-059. NC...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR NCZ001-002-018. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR NCZ001-002-018. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR NCZ001-018. WIND CHILL ADVISORY FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR NCZ003>006-019-020. WV...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR WVZ042>045. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR WVZ042>045. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR WVZ042-043-045. && $$ SYNOPSIS...NF/SK NEAR TERM...NF/SK SHORT TERM...RAB LONG TERM...DS AVIATION...NF/PM/SK CLIMATE...DS
AREA FORECAST DISCUSSION
NWS BLACKSBURG VA
1207 PM EST SUN JAN 5 2014 .SYNOPSIS... A WARM FRONT WILL APPROACH THE AREA FROM THE SOUTH TODAY... SPREADING LIGHT RAIN ACROSS THE AREA MAINLY EAST OF THE BLUE RIDGE. AN ARCTIC FRONT WILL ARRIVE LATE TONIGHT. ITS PASSAGE WILL BRING SOME VERY COLD AIR TO OUR REGION WITH DANGEROUS WIND CHILLS. THIS AIRMASS WILL LAST INTO TUESDAY...THEN SLOWLY MODERATE FOR THE SECOND HALF OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 1205 PM EST SUNDAY... CANCELLED THE FREEZING RAIN ADVISORY AS ALL TEMPERATURES FROM REPORTING SITES HAVE RISEN TO ABOVE FREEZING...EXCEPT FOR A FEW LOCATIONS WEST OF THE AREA OF LIGHT PRECIP THAT ARE RIGHT AT FREEZING. ADJUSTED SOME HIGH TEMPS DOWN A BIT WITH WEAK WEDGE CONTINUING ACROSS NORTHEAST PORTION OF THE AREA. ADJUSTED SOME MAX TEMPS UPWARD IN FAR SOUTHWEST GIVEN CURRENT TEMPS. MINOR CHANGES TO POPS REMAINDER OF AFTERNOON WITH HRRR AND RAP DOING BEST WITH CURRENT AREA OF LIGHT RAIN AND HAVE TRIED TO INDICATE A ZONE OF HIGHEST POPS CONTINUING JUST EAST OF BLUE RIDGE WITH LOWER POPS FARTHER EAST BORDERING WAKEFIELD FCST AREA...AT LEAST UNTIL LATE AFTERNOON BEFORE THIS ZONE FINALLY SHIFT EAST AND NORTH OUT OF THE FCST AREA BY EARLY EVENING. PREV DISCUSSION AS OF 1025 AM EST SUNDAY... UPDATED TO CANCEL FREEZING RAIN ADV FOR MTNS OF NW NC AND UP THE BLUE RIDGE TO FLOYD WHERE HIGHER ELEVATIONS ARE WELL ABOVE FREEZING. STILL POCKETS OF SUB FREEZING TEMPS IN PARTS OF NEW RIVER VALLEY WITH SOME GROUND TEMPS LIKELY TO STILL BE BELOW FREEZING...AND THEN NORTHWARD INTO ROANOAKE VALLEY AND MUCH OF FOOTHILLS AND PIEDMONT STILL HAVE POCKETS OF SUB FREEZING TEMPS. THUS WILL KEEP THE ADVISORY GOING UNTIL NOON IN THOSE LOCATIONS. MOST OF PRECIP HAS MOVED EAST OF BLUE RIDGE...BUT DRIZZLE STILL POSSIBLE AND ONGOING SLICK SPOTS UNTIL ALL TEMPS HAVE RISEN ABOVE FREEZING. PREVIOUS DISCUSSION AS OF 830 AM EST SUNDAY... NUMEROUS CALLS COMING INTO THE OFFICE THIS MORNING OF AUTO ACCIDENTS CAUSED BY SLICK ROADS EAST OF THE BLUE RIDGE. GROUND TEMPERATURES IN MANY AREAS WERE SIGNIFICANTLY CHILLED DURING THE POLAR SURGE A COUPLE DAYS AGO...AND WITH AIR TEMPERATURES ACROSS THE PIEDMONT HOVERING AROUND FREEZING...GIVE OR TAKE A DEGREE... EXPECT ICING TO CONTINUE FOR THE NEXT FEW HOURS. EVEN AFTER AIR TEMPERATURES WARM LATER THIS MORNING...EXPECT ICING ON THE GROUND TO BE SLOW TO MELT. MOTORISTS SHOULD EXERCISE EXTREME CAUTION WHEN TRAVELING THIS MORNING AS THE ICING WILL BE VERY DIFFICULT TO SEE UNTIL THEY ARE ALREADY DRIVING ON IT. TO MAKE MATTERS WORSE... SURFACE OBSERVATIONS ACROSS THE MOUNTAINS INDICATE VISIBILITIES FOGGING DOWN AS MOIST AIR CONTINUES TO WORK IN FROM THE SOUTHWEST. EXPECT THESE CONDITIONS TO BE SLOW TO IMPROVE THROUGH THE DAY. WAVES OF LIGHT RAIN WILL PASS ACROSS THE REGION THROUGH THE DAY AS MINOR DISTURBANCES EMBEDDED IN THE SOUTHWESTERLY FLOW ALOFT MOVE ACROSS THE CENTRAL APPALACHIAN CHAIN. BELIEVE THAT THE LIGHT RAIN WILL LIMIT HEATING ACROSS THE EAST AND HAVE THEREFORE HELD HIGHS A LITTLE BELOW GUIDANCE...NAMELY THE UPPER 30S AND THE LOW 40S. RAINFALL WILL NOT BE AS WIDESPREAD ACROSS THE MOUNTAINS...AND EXPECT TO SEE MID AND UPPER 40S THIS AFTERNOON. ALL OF THIS WARM AIR IS FLOWING IN AHEAD OF OUR NEXT STRONG COLD FRONT...EXPECTED TO ENTER THE REGION SHORTLY AFTER MIDNIGHT. THE FRONT WILL SHIFT EAST VERY RAPIDLY...EXITING OUR AREA BEFORE SUNRISE. WITH PRECIPITABLE WATER VALUES RISING TO AROUND AN INCH BY MIDNIGHT...BELIEVE ALL LOCATIONS WILL SEE A BRIEF SHOT RAIN AS THE FRONT PASSES. RAIN WILL CHANGE VERY RAPIDLY TO SNOW AS TEMPERATURES DROP BEHIND THE FRONT...WITH SNOW ACCUMULATING ACROSS THE WESTERN RIDGES THROUGH THE NIGHT. THE GREATEST IMPACTS OF THE COLD FRONT WILL BE FELT ALONG THE WESTERN MOST COUNTIES FROM GREENBRIER TO WATAUGA. HIGHEST SNOWFALL ACCUMULATIONS WILL OCCUR IN WESTERN GREENBRIER AND NORTHERN SUMMERS COUNTIES...WHERE LOCALLY 6 TO 9 INCHES ARE POSSIBLE THROUGH MONDAY MORNING. LESSER AMOUNTS OF 2 TO LOCALLY 5 INCHES ARE POSSIBLE ACROSS THE WEST FACING SLOPES IN THE MOUNTAIN EMPIRE AND NORTHERN NORTH CAROLINA. GUSTY WINDS BEHIND THE FRONT WILL RESULT IN BLOWING SNOW AND POSSIBLY WHITE OUT CONDITIONS THAT MAY PERSIST INTO THE MONDAY MORNING COMMUTE. IN ADDITION...THE COLD AIR WILL LIKELY RESULT IN FLASH FREEZING OF WET SURFACES FROM RAINFALL EARLIER IN THE EVENING...MAKING FOR SLICK ROADWAYS. AS A RESULT...HAVE ISSUED A WINTER STORM WARNING FOR OUR WESTERN MOST COUNTIES...AND A WIND ADVISORY FOR ALL OF OUR MOUNTAIN COUNTIES...BEGINNING AT MIDNIGHT TONIGHT. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... AS OF 545 AM EST SATURDAY... BY THE BEGINNING OF THIS PERIOD WE WILL BE FIRMLY ENTRENCHED IN THE THRAWLS OF AN INTENSE ARCTIC AIR MASS THAT PROMISES TO BRING SOME OF THE COLDEST TEMPERATURES IN A COUPLE OF DECADES ALONG WITH DANGEROUSLY COLD WIND CHILLS. ALTHOUGH THE BULK OF SYNOPTICALLY DRIVEN PCPN WILL BE ENDING DURING THIS TIME FRAME...UPSLOPE SNOW SHOWERS WILL MOST CERTAINLY CONTINUE GIVEN STRENGTH OF CAA. IN FACT...FEELS MODELS ARE WAY TO QUICK IN ENDING SHSN...AND HAVE EXTENDED WELL BEYOND THE MODEL INDICATIONS OF 18Z MON...ALL THE WAY TO EARLY TUESDAY MORNING. GRANTED...THE MOST SIGNIFICANT SNOWFALL WILL END BY 18Z MON...BUT EXPECT SHSN TO CONTINUE IN EARNEST ALONG WEST FACING SLOPES WITH ADDITIONAL ACCUMULATIONS OF ANOTHER INCH OR TWO POSSIBLE IN THIS TIME FRAME. THUS...THE SNOW PORTION OF THE WINTER STORM WARNING WILL REMAIN IN EFFECT UNTIL 00Z TUE. WIND CHILL WILL PERHAPS BE THE MOST SIGNIFICANT ISSUE WITH THIS EVENT...WITH DANGEROUSLY COLD -20 TO -40F WIND CHILLS IN PLACE OVERNIGHT MONDAY INTO THE FIRST HALF OF THE DAY TUE. HAVE UPGRADED THE WIND CHILL WATCH TO A WIND CHILL WARNING WITH THIS PACKAGE AND ALSO INCLUDED A WIND CHILL ADVISORY FOR THE REMAINDER OF THE CWA...GENERALLY EAST OF I-81 AND I-77...PRINCIPALLY THE PIEDMONT. SUSTAINED WINDS SHOULD REMAIN MOSTLY IN THE 15 TO 30 MPH RANGE LATE TONIGHT THROUGH EARLY TUE...BUT GUSTS OF 45 TO 50 MPH CAN BE EXPECTED IN THE HIGHER ELEVATIONS OF THE ALLEGHANYS AND BLUE RIDGE. THIS SPEEDS DO NOT MEET HIGH WIND WARNING CRITERIA...SO HAVE SIMPLY GONE WITH A WIND ADVISORY AT THIS POINT. A STRONG NON-DIURNAL TEMPERATURE TREND IS EXPECTED MON...WITH TEMPERATURES CONTINUING TO PLUNGE UNTIL EARLY TUE. BY TUE MORNING...THE WESTERN PARTS OF THE CWA WILL BE WELL BELOW ZERO...WITH -20F POSSIBLE IN NW GREENBRIER EARLY TUE...GENERALLY 0 TO -10F ELSEWHERE THROUGH THE ALLEGHANYS TO THE SINGLE DIGITS ACROSS THE PIEDMONT. HAVE FAVORED THE COLDER ECMWF MOS FOR MINS THROUGH THE PERIOD WITH THE COLDER MEX MOS FOR MAXS THROUGH THE PERIOD. THE ARCTIC HIGH WILL BE CENTERED RIGHT OVER THE CWA AT 12Z WED...SO ONLY A SLOW MODERATION IN TEMPERATURES ARE EXPECTED WED AS THE -30C AIR AT 850MB FINALLY LIFTS OUT OF THE CWA. && .LONG TERM /THURSDAY THROUGH SATURDAY/... AS OF 200 PM EST SATURDAY... DURING THIS PORTION OF THE FORECAST...THE WEATHER PATTERN ACROSS OUR REGION WILL TRANSITION TO ONE DOMINATED MORE BY THE SOUTHERN STREAM OF THE JET STREAM RATHER THAN THE NORTHERN STREAM. WITHIN THIS PATTERN WILL BE A SERIES OF FAST MOVING DISTURBANCES...EACH WITH THE POTENTIAL TO BRING SOME LIGHT PRECIPITATION TO PARTS OR ALL OF THE FORECAST AREA. SPECIFICALLY...WE ARE EXPECTING A SYSTEM THURSDAY AFTERNOON AND THURSDAY NIGHT TO IMPACT MAINLY THE WESTERN PARTS OF THE REGION. ONE FRIDAY INTO FRIDAY NIGHT MAY SKIRT THE FAR WESTERN PART OF THE REGION. FINALLY...ONE LATE FRIDAY NIGHT THROUGH SATURDAY HAS THE POTENTIAL OF BRINING RAIN TO ALL OF THE REGION. EACH DAY...TEMPERATURES WILL TREND MILDER SO THAT BY SATURDAY HIGH TEMPERATURES ARE FORECAST IN THE LOWER 50S ACROSS THE MOUNTAINS WITH MID TO UPPER 50S ACROSS THE PIEDMONT. MOST OF THE PRECIPITATION ASSOCIATED WITH THE DISTURBANCES WILL BE IN THE FORM OF RAIN. ENOUGH COLD AIR WILL STILL BE AROUND THURSDAY NIGHT INTO FRIDAY FOR SOME POCKETS OF FREEZING RAIN. && .AVIATION /18Z SUNDAY THROUGH FRIDAY/... AS OF 730 AM EST SUNDAY... RADAR INDICATES AREAS OF LIGHT RAIN AND FREEZING RAIN MAINLY EAST OF THE BLUE RIDGE THIS MORNING AS WARMER GULF MOISTURE RIDES IN OVERTOP COLDER AIR AT THE SURFACE. TEMPERATURES FOR DAN...ROA AND LYH ARE HOVERING AT FREEZING...GIVE OR TAKE A DEGREE...AND EXPECT LIGHT FREEZING RAIN TO PERSIST THROUGH ABOUT 10 AM FOR DAN AND ROA...WHEN TEMPERATURES WILL WARM ABOVE FREEZING. WARMING WILL BE SLOWER AT LYH...AND MAY TAKE UNTIL NOON FOR FREEZING RAIN TO END. ACCUMULATIONS WILL BE LIGHT...NOT MUCH MORE THAN A GLAZING. DRIER AND WARMER CONDITIONS ARE OBSERVED AT BLF AND BCB...WITH TEMPERATURES ABOVE FREEZING. CLOUD COVER JUST MOVED IN AT LWB...WHICH IS SITTING IN THE UPPER TEENS BUT IS OTHERWISE DRY. LOW CLOUDS WILL PERSIST ACROSS THE REGION THROUGH THE DAY AS MOIST AIR BUILDS IN AHEAD OF A STRONG COLD FRONT. CEILINGS WILL SPEND THE DAY AROUND 1 KFT OR LOWER FOR MOST LOCATIONS. IN ADDITION...VISIBILITIES EAST OF THE BLUE RIDGE MAY BRIEFLY DROP INTO THE 1SM TO 2SM RANGE AS WAVES OF RAIN PASS OVERHEAD. THE COLD FRONT WILL ENTER THE REGION AFTER MIDNIGHT MONDAY. WILL SEE SCATTERED SHOWERS ALONG AND AHEAD OF THE FRONT QUICKLY TRANSITION TO SNOW AFTER THE FRONT PASSES. VERY COLD AIR WILL ARRIVE BEHIND THE FRONT...WHICH IS LIKELY TO CAUSE FLASH FREEZING OF WET SURFACES FROM RAINFALL EARLIER IN THE EVENING. ONCE THE SNOW SETS IN...EXPECT SEVERAL HOURS OF VISIBILITIES AROUND 1SM FOR ROA WESTWARD...WHILE SNOW SHOWERS WILL NOT PERSIST AS LONG FOR DAN AND LYH. EXPECT THE CHANGE OVER TO SNOW AROUND 06/08Z AT BLF AND LWB...06/09Z FOR BCB AND ROA...AND 06/10Z FOR LYH AND DAN. ACCUMULATIONS OF AROUND 4 INCHES ARE POSSIBLE FOR BLF...AN INCH OR TWO AT LWB...AND LESS THAN AN INCH FOR ROA AND BCB. STRONG WINDS FROM THE NORTHWEST WILL ACCOMPANY THE FRONT...WITH OCCASIONAL 35 TO 40 KT GUSTS EXPECTED ACROSS THE MOUNTAINS. STRONG CROSS- BARRIER FLOW WILL ALSO RESULT IN MODERATE TURBULENCE. WHILE WINDS WILL DIMINISH SOMEWHAT ON MONDAY AFTERNOON...A SECONDARY SHOT OF ARCTIC AIR WILL ARRIVE MONDAY NIGHT...CAUSING WIND SPEEDS TO INCREASE ONCE AGAIN. THIS ARCTIC AIR WILL CAUSE TEMPERATURES TO FALL INTO THE POSITIVE SINGLE DIGITS EAST OF THE BLUE RIDGE...AND FALL BELOW ZERO TO THE WEST. SNOW SHOWERS WILL PERSIST ACROSS THE MOUNTAINS THROUGH TUESDAY MORNING...BEFORE HIGH PRESSURE SETTLES IN...CAUSING WIND SPEEDS AND SNOW SHOWERS TO DECREASE. && .CLIMATE... AS OF 220 PM EST THURSDAY... FORECAST LOW TEMPERATURES MONDAY NIGHT...EARLY JAN 7...ARE FORECAST TO BE AROUND ZERO OR A BIT BELOW ZERO ACROSS THE MOUNTAINS AND IN THE SINGLE DIGITS TO NEAR 15 ACROSS THE PIEDMONT. OF OUR CLIMATE SITES...ALL BUT DANVILLE IS FORECAST TO BREAK THE RECORD. HIGH TEMPERATURES ON TUESDAY JANUARY 7 ARE FORECAST TO BE IN THE TEENS ACROSS THE MOUNTAINS AND LOW TO MID 20S ACROSS THE PIEDMONT. OUR CURRENT FORECAST PLACES THE RECORD MINIMUM HIGH TEMPERATURE RECORDS IN JEOPARDY AT BOTH BLACKSBURG AND LEWISBURG WHILE THE OTHER LOCATION WILL SEE TEMPERATURES WITHIN A FEW DEGREES OF THE RECORDS. JANUARY 7 RECORDS LOWS MINIMUM HIGHS BLACKSBURG VA... 1/1988 19/1988 BLUEFIELD WV.... 0/1970 11/1988 DANVILLE VA..... 10/1969 26/1988 ROANOKE VA...... 8/1970 17/1988 LEWISBURG WV.... 7/2004 11/1988 LYNCHBURG VA.... 10/1912 17/1988 && .RNK WATCHES/WARNINGS/ADVISORIES... VA...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR VAZ007-009>020-022>024. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR VAZ007-009>020-022>024. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR VAZ007-009-015. WIND CHILL ADVISORY FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR VAZ032>035-043>047-058-059. NC...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR NCZ001-002-018. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR NCZ001-002-018. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR NCZ001-018. WIND CHILL ADVISORY FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR NCZ003>006-019-020. WV...WIND ADVISORY FROM MIDNIGHT TONIGHT TO 1 PM EST TUESDAY FOR WVZ042>045. WIND CHILL WARNING FROM 5 PM MONDAY TO 3 PM EST TUESDAY FOR WVZ042>045. WINTER STORM WARNING FROM MIDNIGHT TONIGHT TO 7 PM EST MONDAY FOR WVZ042-043-045. && $$ SYNOPSIS...NF/SK NEAR TERM...NF/SK SHORT TERM...RAB LONG TERM...DS AVIATION...NF/PM CLIMATE...DS
YOU CAN SEE AN ILLUSTRATED VERSION OF THE FORECAST DISCUSSION AT
WWW.WEATHER.GOV/SEATTLE/GAFD/LATEST_WEBAFD.HTML

FORECAST DISCUSSION FOR ROUTINE AFTERNOON FORECAST ISSUANCE

.SHORT TERM...TONIGHT AND MONDAY ISSUED AT 204 PM CST SUN JAN 5 2014 LATEST RUC ANALYSIS AND SATELLITE/RADAR IMAGERY SHOW A STRENGTHENING AREA OF LOW PRESSURE MOVING NORTHEAST OVER THE OHIO VALLEY. A WIDE SWATH OF HEAVY SNOW IS IMPACTING ST LOUIS TO THE THUMB OF MICHIGAN JUST NORTH OF THE SURFACE LOW TRACK...AND IS NOT SHOWING ANY SIGNS OF LIFTING INTO EAST-CENTRAL WISCONSIN. ALTOSTRATUS ON THE NORTHERN PERIPHERY OF THIS SYSTEM IS MOVING ACROSS MUCH OF CENTRAL AND NORTHEAST WISCONSIN AND IS PREVENTING ANY SUNSHINE TO OFFSET THE COLD TEMPERATURES. READINGS THIS AFTERNOON REMAIN BELOW ZERO WEST OF A WAUTOMA TO IRON MOUNTAIN LINE...WHERE WIND CHILLS ARE NEAR OR BELOW WIND CHILL ADVISORY CRITERIA (-20F). FARTHER WEST...A LOBE OF THE POLAR VORTEX IS DROPPING SOUTHEAST OVER THE DAKOTAS WHERE TEMPS ARE IN THE TEENS BELOW ZERO WITH WINDS GUSTING OVER 40 KTS. ALSO SEEING LOWER VSBYS WITHIN SOME CLOUD COVER IN THIS REGION...BUT THINK MUCH OF THESE OBS CAN BE ATTRIBUTED TO BLOWING SNOW. AS THE POLAR VORTEX AND ASSOCIATED ARCTIC AIR MOVES ACROSS THE REGION...LIGHT SNOW CHANCES AND WIND CHILL HEADLINES ARE THE MAIN FORECAST CONCERNS. TONIGHT...THE LOW PRESSURE SYSTEM WILL MOVE FROM THE OHIO VALLEY TO THE EASTERN GREAT LAKES THIS EVENING. CYCLONIC FLOW AROUND THE LOW WILL DELAY THE BITTERLY COLD ARCTIC AIR FROM REACHING NORTHEAST WISCONSIN UNTIL LATE IN THE EVENING OR EARLY OVERNIGHT. OTHERWISE A LOBE OF THE POLAR VORTEX WILL SWING EAST FROM THE NORTHERN MISSISSIPPI VALLEY TO NORTHEAST WISCONSIN. AS THIS OCCURS...SHOULD SEE AN AREA OF LOW AND MID CLOUDS MOVE EAST OVER THE FORECAST AREA. SINCE THE LOWER VSBYS OVER THE DAKOTAS HAS THE LOOK OF BLOWING SNOW...WILL REMOVE THE FLURRY MENTION AFTER MIDNIGHT. HOWEVER...MODELS TRY TO RETURN SOME MOISTURE FROM THE SOUTH AHEAD OF THE SHORTWAVE LOBE AND PRODUCE LIGHT SNOW OR FLURRIES ALONG THE LAKE MICHIGAN SHORELINE LATE TONIGHT. THIS POSSIBILITY STILL LOOKS REASONABLE AND WILL LEAVE IN THE FORECAST. OTHERWISE...THE MAIN STORY WILL BE THE ADVECTION OF THE COLDEST AIR THE REGION HAS OBSERVED IN YEARS. 850MB TEMPS WILL FALL INTO THE -25C TO -35C RANGE MY 12Z MON WHICH WILL BRING IN SURFACE TEMPS FROM 30 BELOW OVER NORTH-CENTRAL WISCONSIN TO ABOUT 15 BELOW AT THE LAKE MICHIGAN SHORELINE. COMBINED WITH WINDS GUSTING TO 25 TO 30 MPH...PROJECTED WIND CHILLS WILL FALL INTO THE 40 TO 55 DEGREES BELOW ZERO RANGE. EASTERN SECTIONS MAY NOT REACH WIND CHILL WARNING CRITERIA UNTIL AFTER MIDNIGHT...BUT THEY WILL BE FALLING RAPIDLY THROUGH THE EVENING...SO WILL LEAVE THE WARNING START TIMES ALONE TO INCLUDE THE ADVISORY RAMP UP TIME. MONDAY...THE POLAR VORTEX WILL BE EXITING NORTHEAST WISCONSIN EARLY IN THE MORNING AND WILL LEAVE A SMALL CHANCE OVER DOOR COUNTY TO ACCOUNT FOR THAT. SHOULD SEE A PERIOD OF DECREASING CLOUDS UNTIL MID AND HIGH CLOUDS SLIDE IN FROM THE NORTH DURING THE AFTERNOON. NOT SURE HOW MUCH OF THESE CLOUDS WILL HOLD TOGETHER...SO WILL KEEP SKIES IN THE PARTLY CLOUDY RANGE. ARCTIC HIGH PRESSURE WILL SLIDE SOUTHEAST TOWARDS THE CENTRAL PLAINS WHICH SHOULD KEEP A TIGHT PRESSURE GRADIENT IN PLACE. COMBINED WITH TEMPERATURES IN THE NEGATIVE TEENS BELOW ZERO FOR HIGHS...WIND CHILLS WILL REMAIN IN THE 35 TO 45 DEGREES BELOW ZERO RANGE. WIND CHILL WARNINGS WILL CONTINUE AS A RESULT. .LONG TERM...MONDAY NIGHT THROUGH SUNDAY ISSUED AT 204 PM CST SUN JAN 5 2014 THE BITTER COLD REGIME OF ARCTIC AIR WILL STUBBORNLY DIMINISH THIS WEEK AS THE UPPER FLOW TURNS MORE ZONAL WITH THE INTRODUCTION OF WESTERLY PACIFIC FLOW AND MILDER CONDITIONS BY NEXT WEEKEND. EVEN THOUGH THE CENTER OF THE POLAR VORTEX IS LIFTING NORTHEAST OF THE AREA MONDAY NIGHT INTO EARLY TUESDAY...BITTER COLD AIR MASS LEFT IN ITS WAKE COMBINED WITH WEST WINDS 10 TO 20 MPH WILL CONTINUE TO PRODUCE WARNING WIND CHILL NUMBERS THROUGH A GOOD PORTION OF TUESDAY BEFORE SUBSIDING TO ADVISORY CRITERIA IN THE AFTERNOON. HIGH PRESSURE RIDGE BEGINS TO SETTLES OVER THE AREA LATER TUESDAY AFTERNOON INTO TUESDAY NIGHT. EVEN THOUGH 850 TEMPS BEGIN TO MODIFY...EXPECTED CLEAR SKIES AND LIGHT WINDS WILL ALLOW TEMPS TO PLUMMET WELL BELOW ZERO AGAIN. DEPENDING ON WINDS...PARTS OF THE THE AREA MAY STILL WARRANT WIND CHILL ADVISORY HEADLINES. THE COLD HIGH PRESSURE REMAINS SETTLED OVER THE REGION WEDNESDAY NIGHT AND THURSDAY FOR CONTINUED BELOW NORMAL SUB ZERO TEMPERATURES. A WEAK SYSTEM IS PROGGED TO PASS SOUTH OF THE AREA WEDNESDAY NIGHT AND THURSDAY...HAS TRENDED SOUTH LEAVING THE AREA MORE IN THE COLD AIR MASS. WAA PATTERN BEGINS IN EARNEST LATER THURSDAY INTO FRIDAY WITH TEMPERATURES APPROACHING THE FREEZING MARK FOR THE WEEKEND. DUE TO THE ZONAL FLOW...MODELS ARE PRODUCING DIFFERENT SOLUTIONS WITH TIMING OF WEAK SHORT WAVES PASSING OVER OR NEAR THE GREAT LAKES REGION FRIDAY INTO SUNDAY. USUALLY THE PACIFIC SYSTEMS ARE ON THE DRY SIDE BUT WITH H850 TEMPERATURES ABOVE ZERO THIS WEEKEND...PCPN TYPE ISSUES WILL INCREASE. && .AVIATION...FOR 18Z TAF ISSUANCE ISSUED AT 1128 AM CST SUN JAN 5 2014 A WINTER CYCLONE WILL PASS TO OUR SOUTHEAST THROUGH THE AFTERNOON HOURS. BACK EDGE OF THE PRECIP LIKELY TO REMAIN SOUTH OF THE FORECAST AREA...THOUGH A BKN TO OVC MID-LEVEL CLOUD DECK WILL BE OVERHEAD THROUGH THE REST OF THE AFTERNOON. THEN A SHARP UPPER LEVEL DISTURBANCE WILL SHIFT EAST ACROSS THE FORECAST AREA TONIGHT. SHOULD SEE AN ADDITIONAL AREA OF MID-CLOUDS WITH THIS SYSTEM...THOUGH MUCH OF THE AREA LOOKS TO REMAIN DRY. THE EXCEPTION COULD BE ALONG THE LAKE MICHIGAN SHORELINE...WHERE MOISTURE FROM THE CYCLONE TO THE SOUTH MAY WORK NORTHWARD AHEAD OF THE DISTURBANCE TO PRODUCE FLURRIES OR VERY LIGHT SNOW. OTHERWISE...THE MAIN STORY WILL BE THE INCOMING VERY COLD TEMPERATURES TONIGHT AND MONDAY ALBEIT WITH VFR CONDITIONS AND GUSTY NORTHWEST WINDS. && .GRB WATCHES/WARNINGS/ADVISORIES... WIND CHILL WARNING FROM 6 PM THIS EVENING TO NOON CST TUESDAY FOR WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. WIND CHILL ADVISORY UNTIL 6 PM CST THIS EVENING FOR WIZ005- 010>012-018-019-030-035-036. && $$ SHORT TERM.....MPC LONG TERM......TDH AVIATION.......MPC