FXUS61 KAKQ 182124 AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 424 PM EST WED FEB 18 2015 .SYNOPSIS... A STRONG COLD FRONT MOVES OFF THE COAST THIS EVENING. ARCTIC HIGH PRESSURE BUILDS OVER THE AREA THURSDAY AND FRIDAY. LOW PRESSURE APPROACHES FROM THE SOUTHWEST THIS WEEKEND. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... ARCTIC COLD FRONT QUICKLY MOVES EAST ACROSS THE FA THIS EVENING... THEN OFFSHORE BY MIDNIGHT. BAND OF SNOW SHWRS TO ACCOMPANY ITS PASSAGE THIS EVENING WILL QUICKLY END BY MIDNIGHT. KEPT A 2-3 HR WINDOW OF LIKELY POPS WITH THE ACTUAL FROPA WITH AN AREA OF CHC POPS BEHIND IT. ANY QUICK BURST OF SNOW COULD PUT DOWN A QUICK 1/2 INCH OVER MOST OF THE FA...HIGHEST AMOUNTS ALONG THE ERN SHORE WHERE AN UP TO AN INCH IS POSSIBLE. TIMING APPEARS TO BE 4-6 PM WEST OF I95...5-7 PM I95 CORRIDOR...6-8 PM NRN NECK/MIDDLE PEN...7-9 PM ERN SHORE...SERN VA/NE NC. TEMPERATURES QUICKLY DROP OFF INLAND BEHIND THE ARCTIC FRONT. WIND CHILLS HAVE BEEN FINE TUNED WITH THIS PACKAGE. GIVEN THE EXTREMELY COLD AIRMASS AND FORECASTED WINDS...HAVE ISSUED A WIND CHILL ADVISORY FOR THE ENTIRE AREA STARTING LATE TONIGHT AND CONTINUE IT THROUGH NOON FRIDAY. DOING IT THIS WAY TO INDICATE THE IMPACT THE COLD WILL HAVE THURSDAY DESPITE WIND CHILLS GOING ABOVE ZERO FOR A FEW HOURS THURSDAY BEFORE QUICKLY FALLING THURSDAY NIGHT. LOWS IN THE UPPER SINGLE DIGITS IN THE PIEDMONT...TO MID TEENS SE COAST. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH SATURDAY NIGHT/... UPPER TROUGH PIVOTS EAST INTO NEW ENGLAND FOR THU/FRI. THIS WILL BRING ANOTHER ROUND OF FRIGID CONDITIONS TO THE AREA. DANGEROUSLY COLD AIR IS ON THE WAY...QUITE POSSIBLY THE COLDEST WE'VE SEEN OVER OUR REGION IN QUITE SOME TIME (SEE CLIMATE SECTION BELOW). 12Z DATA EVEN SUGGESTING SOME POTOMAC RIVER...CHESAPEAKE BAY STREAMERS THU AFTERNOON. THINK IT WILL BE TOO DRY IN LOWER LVLS FOR ANY FLURRIES TO OCCUR. HIGHS THU IN THE UPPER TEENS TO LOWER 20S...COLDEST NIGHT OF THIS LATEST BRUTAL COLD AIR SURGE WILL COME THU NIGHT/FRI MORNING...AS SFC HIGH OVER KY SLOWLY BUILDS E. BEST CHC FOR WINDS TO DECOUPLE IS WEST OF I95 AFTER MIDNIGHT AS 1032+MB HIGH PRESSURE BUILDS OVRHD THU NGT/FRI MORNING. IT APPEARS THAT THE MOS GUID IS HAVING A HARD TIME WITH THE FRESH SNOWPACK...SO FORECASTED MINS WILL REMAIN BLO EVEN THE COLDEST MOS GUIDANCE. LOWS WITHIN A DEGREE OR TWO OF ZERO WEST OF I-95 AND IN THE SINGLE DIGITS ABOVE ZERO EAST (AROUND 10 F AT SE VA/NE NC COAST). SUNNY BUT CONTINUED COLD WITH LESS WIND FRI DURING THE AFTERNOON. HIGHS AGAIN UPPER TEENS TO LOWER 20S. RIDGE AXIS MOVES OFFSHORE FRIDAY NIGHT. ANTHR VRY COLD NIGHT WITH INCREASING CLOUDS AFTER MIDNIGHT AHEAD OF THE NEXT SYSTEM APPROACHES FROM THE SW. WINDS TURN SOUTH...BUT TMPS WILL LIKELY HAVE ENOUGH TIME TO DROP TO BETWEEN 5 AND 15 DEGREES BEFORE BEGINNING TO RISE LATE. CHALLENGING FORECAST FOR SAT EVEN AT THIS POINT. MODELS SOMEWHAT SLOWER AT BRINGING IN THE WARM ADVECTION PCPN SAT. (GFS THE FASTEST IN THE MORNING...NAM A BIT SLOWER IN THE AFTERNOON. 12Z/18 ECMWF IS THE OUTLIER WITH KEEPING SAT DRY ACROSS THE AREA AND MOST OF SAT NIGHT). WILL GO WITH A MODEL COMPROMISE FOR NOW AND BRING N SOME LIGHT WINTER PCPN ACROSS THE PIEDMONT SAT MORN...AND OVERSPREADING THE NRN HALF OF THE FA SAT AFTERNOON. RAIN ACROSS THE SOUTH. EVEN AFTER THE COLD START...TMPS BY LATE IN THE DAY RISE INTO THE M-U30S. WARM FRONT LIFTS NORTH ACROSS THE AREA SAT EVENING. KEPT CHC TO LIKELY POPS FOR NOW BUT ALL IN THE FORM OF RAIN AS TMPS REMAIN STEADY OR SLOWLY RISE OVERNIGHT. && .LONG TERM /SUNDAY THROUGH WEDNESDAY/... UPPER FLOW REMAINS CHARACTERIZED BY AN ANOMALOUS WRN CONUS RIDGE THRU THE PERIOD. THIS WILL RESULT IN ANOTHER AMPLIFICATION OF THE ERN CONUS TROUGH THRU THE MIDDLE OF NEXT WEEKEND...AND A RETURN TO BELOW NORMAL TEMPS. TO BEGIN THE PERIOD...SMALL AMPLITUDE WAVE LIFTS FROM THE OH VALLEY INTO THE NE STATES SUN. ASSOCIATED SFC LOW LIFTS INTO THE NE STATES...WITH A TRAILING COLD FRONT CROSSING THE REGION SUN NIGHT. LOW LEVEL SWLY/RETURN FLOW BEHIND DEPARTING HIGH PRESSURE WILL RESULT IN MODERATING TEMPS AND INCREASING MOISTURE SUN AFTERNOON. THE AFOREMENTIONED WAVE AND INCREASING WINDS ALOFT WILL PROVIDE SUFFICIENT UVM FOR PRECIP ALONG THE FRONT SUN AFTERNOON. MAINTAINED LIKELY POPS. WAA/THICKNESS RISES WILL HELP MODERATE TEMPS...BUT HAVE UNDERCUT GUIDANCE DUE TO LINGERING SNOW PACK. HIGHS GENERALLY LOW-MID 50S. FRONT CLEARS THE COAST SUN NIGHT...BUT STALLS OFF THE SE COAST AS WSW FLOW ALOFT PERSISTS. 1040+MB ARCTIC HIGH BUILDS OVER THE MIDWEST SUN NIGHT...AS COLD/DRY AIR SURGES INTO THE MID-ATLANTIC. EXPECT THE BRUNT OF THE PRECIP TO PUSH OFFSHORE SUN NIGHT...BUT COULD SEE A CHANGE OVER TO WINTRY MIX OF PRECIP OVER THE NE ZONES. THEREAFTER...GUIDANCE COMING INTO BETTER AGREEMENT THRU MID WEEK...WITH SUPPRESSING THE PRECIP OVER THE SE COAST/GULF STREAM. THE ECMWF HAS TRENDED TOWARD THE GFS...BUT KEEPS PRECIP ALONG THE SE COAST MON NIGHT-TUES NIGHT AS LOW PRESSURE DEVELOPS ALONG THE COASTAL BOUNDARY TUES. HAVE KEPT CHANCE POPS FOR UNCERTAINTY SE VA/NE NC MON NIGHT-TUES. AT THIS TIME...THERMAL PROFILES AND THICKNESSES SUGGEST ANY POTENTIAL PRECIP WOULD BE FROZEN. SFC LOW LIFTS AWAY FROM THE REGION WEDS...BEFORE THE NEXT CLIPPER FRONT CROSSES THE REGION WEDS. && .AVIATION /21Z WEDNESDAY THROUGH MONDAY/... AN ARCTIC COLD FRONT APPROACHES THE REGION FROM THE WEST LATE TODAY WITH AN INCOMING SCT DECK AROUND 4000FT AGL BY LATE THIS AFTN. SNOW SHOWERS WILL DEVELOP ALONG THE FRONT BY EARLY EVENING AND WILL EXIT THE COAST BEFORE MIDNIGHT. EXPECT MVFR CIGS AROUND 2000FT AGL AND REDUCED VISIBILITIES IN -SHSN BTWN 18/2300Z AND 19/0300Z. A TEMPO GROUP FOR A BRIEF PERIOD OF LIFR VSBYS (1/2SM) AND GUSTY WINDS UP TO 30-35KT WAS ADDED THIS EVENING TO ACCOUNT FOR THE FRONTAL PASSAGE. BEHIND THE FRONTAL PASSAGE...SKIES CLEAR QUICKLY AND A COLD AIR SURGE WILL COMMENCE. NW WINDS REMAIN ELEVATED (GUSTS 25-30KT) LATE TONIGHT INTO FRIDAY. OUTLOOK... HIGH PRESSURE BUILDS BACK INTO THE MID ATLANTIC REGION FROM THE WEST FRIDAY/FRIDAY NIGHT AND THEN SLIDES OFF THE COAST ON SATURDAY. A PROLONGED PERIOD OF LOW CIGS AND LIMITED VISIBILITIES IS EXPECTED SATURDAY AFTN THROUGH EARLY MONDAY AS THE NEXT STORM SYSTEM IMPACTS THE REGION. && .MARINE... RIDGE OF HIGH PRESSURE HAS PUSHED OFFSHORE THIS AFTERNOON AS THE NEXT ARCTIC FRONT LOCATES OVER THE PIEDMONT. WINDS GENERALLY SELY AOB 15 KT...WITH WAVES 1-2 FT AND SEAS 3-5 FT. THE ARCTIC FRONT BLASTS OVER THE WATERS THIS EVENING...WITH FLOW BECOMING W-NW POST FRONTAL. STRONG/STREADY LOW LEVEL CAA IN TANDEM WITH A RAPIDLY STRENGTHEN PRESSURE GRADIENT AND STRONG PRESSURE RISES WILL RESULT IN A RAPID INCREASE IN WINDS OVER THE WATERS. STRONG SCA CONDITIONS EXPECTED IN THE BAY/RIVERS/SOUND WITH SPEEDS OF 20-25 KT AND GUSTS UP TO 30 KT AND GALE CONDITIONS EXPECTED IN THE COASTAL WATERS WITH GUSTS OF 35-40 KT. FEW GALE GUSTS ARE POSSIBLE OVER THE BAY AT THE ONSET OF CAA. HOWEVER...COMBINATION OF WLY COMPONENT TO THE WIND AND SHORT DURATION HAVE PREVENTED AN UPGRADE TO GALE HEADLINES. HAVE OPTED TO MONITOR AND ISSUE SMW AS NEEDED. AN EXTENDED PERIOD OF W-NW WINDS 20-30 KT IS EXPECTED OVER THE WATERS THRU THURS NIGHT...AS LOW PRESSURE DEEPENS OFF THE NE COAST AND 1030+MB SFC HIGH PRESSURE SLOWLY BUILDS EWD. EXTENDED PERIOD OF STRONG WINDS WILL PUSH SEAS TO 5 TO 9 FT TONIGHT THRU THURS NIGHT. WAVES 3-5 FT...UP TO 6 FT IN THE MOUTH OF THE BAY. IN ADDITION TO STRONG WINDS AND HIGH WAVES/SEAS...AN EXTENDED PERIOD OF MODERATE FREEZING SPRAY IS ANTICIPATED FOR THE BAY AND COASTAL WATERS. HEADLINES ARE IN EFFECT. HIGH PRESSURE BUILDS OVER THE WATERS FRI...ALLOWING WINDS TO FINALLY SUBSIDE BELOW SCA CONDITIONS. SEAS WILL BE SLOW TO FALL OFF FRI AFTERNOON. HIGH PRESSURE SLIDES OFFSHORE SAT WITH SLY FLOW RETURNING. LOW PRESSURE LIFTS NORTH OF THE WATERS SUN...WITH A TRAILING COLD FRONT SWEEPING OVER THE WATERS SUN NIGHT. SCA CONDITIONS ARE POSSIBLE. GALE HEADLINES IN THE SRN COASTAL WATERS IN EFFECT THRU THURS MORNING...WITH THE NRN WATERS (NORTH OF PARRAMORE ISLAND) RUNNING THRU FRI MORNING. SCA HEADLINES NOW IN EFFECT THRU FRI MORNING. LATEST MODIS SATELLITE IMAGERY ALSO DEPICTS AN AREA OF ICE IN THE POCOMOKE SOUND THIS AFTERNOON...WITH A FEW ICE CHUNKS BREAKING OFF INTO THE NRN BAY. STRONG W-NW WINDS WILL LIKELY KEEP THE ICE IN THE SOUND...BUT AN EXTENDED PERIOD OF TEMPERATURES NOT GETTING OUT OF THE TEENS MAY ENHANCE THE ICE FIELD THRU FRI. WILL MENTION WAVES IN ICE FREE WATER IN CWF. && .TIDES/COASTAL FLOODING... A PROLONGED PERIOD OF STRONG WEST TO NORTHWEST WINDS TONIGHT THROUGH AT LEAST FRIDAY MORNING MAY RESULT IN BLOWOUT TIDES. WATER LEVELS ARE ANTICIPATED TO DROP TO 1.0 FOOT OR MORE BELOW MLLW DURING THE LOW TIDE CYCLES THURSDAY NIGHT THROUGH FRIDAY NIGHT AND POSSIBLY INTO SATURDAY MORNING/EARLY AFTN. && .CLIMATE... ANOTHER SHOT OF VERY COLD AIR IS EXPECTED TO RETURN TO THE AREA THURSDAY AND FRIDAY. THERE IS A CHANCE THAT HIGH TEMPERATURES THURSDAY AND/OR FRIDAY WILL BE NO HIGHER THAN THE TEENS. AT RICHMOND...THE LAST TIME THERE WERE CONSECUTIVE DAYS WITH HIGH TEMPERATURES IN THE TEENS WAS BACK ON JAN 29TH-30TH IN 1966...WHEN BOTH DAYS HAD A HIGH TEMPERATURE OF 18 DEGS F. THERE WAS ONLY ONE TIME THAT RICHMOND HAD A MINIMUM BELOW ZERO AFTER FEBRUARY 11TH. THIS WAS A READING OF MINUS 1 ON FEB 28 IN 1934. THE LAST TIME RICHMOND HAD A LOW TEMPERATURE BELOW ZERO WAS ON JANUARY 28 IN 2000 WITH A READING OF MINUS 1. THE LAST TIME RICHMOND HAD A HIGH TEMPERATURE ONLY IN THE TEENS WAS FEB 4 1996...18 DEGS F. THE LAST TIME NORFOLK HAD A HIGH TEMPERATURE ONLY IN THE TEENS WAS JAN 19 1994...13 DEGS F. RECORD LOW MAX TEMPERATURES... ...THU 2/19....FRI 2/20 RIC... 27 IN 1903 30 IN 1947 ORF... 30 IN 1993 29 IN 1904 SBY... 25 IN 1993 24 IN 1959 RECORD LOW MIN TEMPERATURES ...THU 2/19....FRI 2/20 RIC... 10 IN 1979 3 IN 1979 ORF... 14 IN 1903 13 IN 1896 SBY... 9 IN 1936 3 IN 1979 && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...WIND CHILL ADVISORY FROM 5 AM THURSDAY TO NOON EST FRIDAY FOR MDZ021>025. NC...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST FRIDAY FOR NCZ012. WIND CHILL ADVISORY FROM 5 AM THURSDAY TO NOON EST FRIDAY FOR NCZ013>017-030>032-102. VA...WIND CHILL ADVISORY FROM MIDNIGHT TONIGHT TO NOON EST FRIDAY FOR VAZ048-049-060>083-085-087>090-092. WIND CHILL ADVISORY FROM 5 AM THURSDAY TO NOON EST FRIDAY FOR VAZ095>100. WIND CHILL ADVISORY FROM 3 AM THURSDAY TO NOON EST FRIDAY FOR VAZ084-086-091-093-094. MARINE...GALE WARNING UNTIL 1 PM EST THURSDAY FOR ANZ654. FREEZING SPRAY ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ630>632- 634-650-652-654-656-658. GALE WARNING UNTIL 10 AM EST THURSDAY FOR ANZ656-658. GALE WARNING UNTIL 10 AM EST FRIDAY FOR ANZ650-652. SMALL CRAFT ADVISORY UNTIL 1 PM EST FRIDAY FOR ANZ630>638. && $$ SYNOPSIS...MPR NEAR TERM...MPR SHORT TERM...MPR LONG TERM...SAM AVIATION...JDM MARINE...SAM TIDES/COASTAL FLOODING... CLIMATE...