Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 120845 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 345 AM EST FRI FEB 12 2016 .SYNOPSIS...
-- Changed Discussion --
LOW PRESSURE WILL MOVE ALONG THE COAST TODAY SPREADING A LIGHT MIX OF RAIN AND WINTRY PRECIPITATION ACROSS THE AREA. AN ARCTIC COLD FRONT WILL CROSS LATE TONIGHT AND BRING THE COLDEST AIR OF THE SEASON THIS WEEKEND. RECORD LOWS ARE POSSIBLE SUNDAY MORNING. A WARMUP WILL BEGIN MONDAY WITH TEMPERATURES REBOUNDING TO NORMAL VALUES AHEAD OF A STRONG LOW PRESSURE SYSTEM WHICH WILL BRING GOOD RAIN CHANCES ON TUESDAY. SEASONABLE WEATHER WILL FOLLOW THROUGH LATE WEEK.
-- End Changed Discussion --
&& .NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
AS OF 330 AM FRIDAY...CONFIDENCE THAT CURRENT WINTER WEATHER ADVISORY WILL PAN OUT HAVE DECREASED IN THESE EARLY MORNING HOURS...BUT NOT QUITE ENOUGH TO CANCEL IT OUTRIGHT. THE MAIN ISSUE IS THE TEMPERATURE PROFILE...THE AIRMASS IS NOT AS COLD AS ANTICIPATED AND INDEED WE ARE SEEING TEMPERATURES RISING ABOVE FREEZING AS A MID LEVEL CLOUD DECK ADVANCES FROM THE SOUTH. BENEATH THIS CLOUD COVER WE HAVE SEEN SUBSTANTIAL TEMPERATURE JUMPS...AS MUCH AS 10 DEGREES OR SO IN A FEW PLACES. MYR IS NOW UP TO 48 DEGREES AND ILM IS NOW ABOVE FREEZING AT 34. MEANWHILE...NORTH OF THE CLOUD DECK...TEMPERATURES REMAIN BELOW FREEZING. THE QUANDARY IS THAT THE BEST CHANCES FOR PRECIPITATION REMAIN NEAREST TO THE COAST CLOSEST IN VICINITY TO THE FORECAST OFFSHORE LOW...WHERE THE TEMPERATURES ARE CURRENTLY THE HIGHEST. COMPOUNDING THE UNCERTAINTY IS THAT THE OFFSHORE LOW HAS YET TO FORM ALONG ITS ASSOCIATED STATIONARY FRONTAL BOUNDARY. REGIONAL OBS AND RADAR LOOPS ALSO HAVE YET TO SHOW PRECIPITATION FORMING. SO...GIVEN THAT THE ADVISORY IS ALREADY OUT...I AM STICKING WITH A WORST-CASE SCENARIO WHILE PARING BACK EXPIRATION TIME FOR THE NORTHERN PORTION OF THE ADVISORY AND CUTTING BACK ON EXPECTED IMPACTS. IT IS STILL POSSIBLE THAT BREAKS IN CLOUD COVER COULD ALLOW TEMPERATURES TO DROP BACK BELOW FREEZING IN ANY LOCATION AND THAT THE DYNAMICAL FORCES INVOLVED IN PRECIPITATION WILL COOL THE AIRMASS ENOUGH TO SUPPORT FREEZING RAIN OR SLEET THIS MORNING. I AM LIMITING ACCUMULATIONS TO A TRACE...WHICH ARE MOST LIKELY ON ELEVATED SURFACES. MODEL PROFILES DO NOT SUPPORT SIGNIFICANT SNOW SO WILL LEAVE MENTION OF SUCH OUT OF THE FORECAST. I EXPECT THE EVENT TO TRANSITION TO ALL RAIN AROUND NOON. FOR TONIGHT...EXPECT CLEARING SKIES WITH TEMPERATURES DROPPING BACK BELOW FREEZING AS THE OFFSHORE LOW PULLS OFF TO THE NORTHEAST.
-- End Changed Discussion --
&& .SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY NIGHT/...
-- Changed Discussion --
AS OF 330 AM FRIDAY...EXTREMELY COLD AIR MASS IN PLACE FOR THE WEEKEND...AND THERE IS A CHANCE FOR RECORD LOWS TO BE SET SUNDAY MORNING...FOLLOWED BY RECORD LOW HIGHS SUNDAY AFTERNOON. STRONG COLD ADVECTION WILL BE ONGOING TO START THE PERIOD BEHIND A COLD FRONT AS ARCTIC HIGH PRESSURE DROPS INTO THE REGION ON THE UPWIND SIDE OF A SHARPENING MID-LEVEL TROUGH. THIS HIGH PRESSURE WILL MOVE OVERHEAD ON SUNDAY IN CONJUNCTION WITH SUBTLY INCREASING THICKNESSES...BUT THIS WILL HAVE MINIMAL IMPACT ON TEMPERATURES THIS PERIOD. NO PRECIP IS FORECAST...SO THE FORECAST CONCERN REVOLVES AROUND THE EXTREMELY COLD AIR SET TO INVADE THE AREA. 850MB TEMPS SATURDAY WILL PLUMMET THROUGH THE AFTN AND INTO THE EVENING...DROPPING AS LOW AS -12C SOUTHERN ZONES TO -15C NORTHERN COUNTIES. COLD ADVECTION DURING PEAK HEATING USUALLY CREATES HIGHS BELOW GUIDANCE...DESPITE FULL INSOLATION...AND THUS THE MOS NUMBERS OF THE MID 40S WELL SOUTH AND AROUND 40 NORTH ARE LIKELY TOO WARM. INHERITED HAS UNDERCUT THESE VALUES BY SEVERAL DEGREES AND WILL MAINTAIN THIS FORECAST WITH HIGHS ONLY AROUND 35 FAR NORTHERN ZONES...TO ABOUT 42 ALONG THE SOUTH SANTEE RIVER. THESE LOW HIGHS AND RAPID COOLING SATURDAY NIGHT WILL PERMIT NEAR RECORD LOWS BY SUNDAY MORNING: RECORD LOWS (YEAR)/FORECAST FOR 2/14: WILMINGTON: 18 (1968)/18 FLORENCE: 15 (1968)/18 NORTH MYRTLE BEACH: 17 (1955)/19 THESE WILL COMBINE WITH GUSTY WINDS TO PRODUCE ADVISORY-LEVEL WIND CHILLS LATE SATURDAY NIGHT. CONTINUED COLD ADVECTION AND DRY- ADIABATIC MIXING WILL KEEP WINDS UP ALL SATURDAY NIGHT...AND IN FACT MAY BE STRONGER OVERNIGHT SATURDAY THAN DURING THE DAY. WINDS OF AT LEAST 10-15 MPH WILL REMAIN GUSTY...AND THIS WILL PRODUCE WIND CHILLS IN THE LOW SINGLE DIGITS. BEING 4TH PERIOD WILL NOT HOIST A WIND CHILL ADVISORY YET...BUT EXPECT ADVISORIES WILL BE NEEDED FOR MOST IF NOT ALL OF THE CWA. EVEN COLDER HIGHS ON SUNDAY...AND EVEN THOUGH COLD ADVECTION SHUTS OFF...VERY SHALLOW MIXING AND THE COLD START WILL KEEP HIGHS BELOW FREEZING FAR NORTH...TO THE UPPER 30S WELL SOUTH. RECORD-LOW MAXIMUMS ARE POSSIBLE AT FLORENCE (RECORD 44) BUT WILL LIKELY BE MISSED AT WILMINGTON (RECORD 29). SUBTLY WARMER LOWS SUNDAY WILL OCCUR THANKS TO SLOWLY DEVELOPING ONSHORE FLOW...BUILDING CLOUD COVER...AND INCREASING MID-LEVEL THICKNESSES. EXPECT MINS SUNDAY NIGHT TO DROP TO AROUND 25-30 DEGREES...WARMEST AT THE SC COAST.
-- End Changed Discussion --
&& .LONG TERM /SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
AS OF 330 AM FRIDAY...A BIG WARMUP FOR THE FIRST HALF OF NEXT WEEK AS HIGH PRESSURE BECOMES POSITIONED OFFSHORE AND SHORTWAVE RIDGING SLOWLY AMPLIFIES AHEAD OF A STRONG TROUGH DIGGING INTO THE MS VLY. AHEAD OF THIS DEEP TROUGH...STRONG SURFACE CYCLOGENESIS WILL DEVELOP AND MOVE INLAND OF THE COAST ON TUESDAY...BRINGING A PERIOD OF RAIN FROM LATE MONDAY THROUGH TUESDAY EVENING. NO PTYPE ISSUES THIS TIME AROUND...BUT GOOD MOIST ADVECTION AND STRONG FORCING SUPPORTS A HIGH QPF EVENT WHICH COULD ENHANCE OR PROLONG ONGOING RIVER FLOODING. TEMPS TUESDAY COULD ACTUALLY RISE TO WELL ABOVE CLIMO IN THE WARM SECTOR AS THE LOW PASSES OFF TO THE NORTH...WHILE REMAINING WEST OF THE COAST. BEHIND THIS LOW A QUICK SHOT OF COOLER AIR WILL FOLLOW...BUT IT WILL TAKE A REINFORCING SHOT OF COLD AIR LATE WEDNESDAY BEHIND A SECONDARY SHORTWAVE TO DRIVE TEMPS BACK DOWN BELOW CLIMO FOR THE END OF THE PERIOD.
-- End Changed Discussion --
&& .AVIATION /09Z FRIDAY THROUGH TUESDAY/... AS OF 06Z...EXPECT VFR OVERNIGHT WITH CONDITIONS DETERIORATING TO MVFR/IFR ON FRIDAY AS A LOW PRESSURE SYSTEM BRINGS RAIN AND WINTRY PRECIPITATION...LOW CIGS...AND AREAS OF FOG. QUIET CONDITIONS EXPECTED OVERNIGHT WHICH WILL ALLOW FOR VFR TO PREVAIL WITH LIGHT WINDS AND BKN/OVC MID CLOUDS. AFTER DAYBREAK...A LOW PRESSURE SYSTEM WILL PASS NEAR THE AREA...WITH NORTHEASTERLY WINDS INCREASING TO 5 TO 10 KTS EARLY. AS A RESULT WILL SEE MIXED PRECIPITATION ACROSS THE AREA...WITH FREEZING RAIN/SLEET/SNOW/RAIN IN THE MORNING HOURS. THIS ALONG WITH GRADUALLY LOWERING CIGS WILL CREATE MVFR. AS TEMPERATURES GRADUALLY RISE FROM THE COAST TO THE INLAND AREAS...WILL SEE A CHANGEOVER TO ALL RAIN. MAY SEE A FEW HOURS LINGERING OF WINTRY PRECIP INLAND. BY THE AFTERNOON HOURS EXPECT ALL PRECIPITATION TO HAVE CHANGED OVER TO RAIN CONTINUING WITH LOW CIGS AND AREAS OF FOG THROUGH THE LATE AFTERNOON/EVENING HOURS. THUS...EXPECT MVFR/IFR WITH WINDS BECOMING NORTHERLY AOB 10 KTS. TOWARDS THE END OF THE TAF PERIOD...CONDITIONS IMPROVE TO VFR WITH GRADUALLY CLEARING SKIES. EXTENDED OUTLOOK...PREDOMINATELY VFR. UNSETTLED WEATHER ON MONDAY AND TUESDAY WITH PRECIPITATION. && .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/... AS OF 330 AM FRIDAY...NORTH WINDS OF 10 TO 15 KTS TODAY WILL BACK TO THE NW TONIGHT...INCREASING TO 15 TO 20 KTS BY AROUND DAYBREAK ON SATURDAY AS AN OFFSHORE LOW EAST OF THE WATERS DEEPENS AND MOVES AWAY FROM THE AREA. SEAS OF AROUND 2 FT THIS MORNING WILL INCREASE TO 2 TO 4 FT LATER TODAY AND TONIGHT. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM FRIDAY...GUSTY NW WINDS SATURDAY WILL CREATE CHOPPY SEAS ACROSS THE COASTAL WATERS. WIND SPEEDS WILL BE 15-25 KTS SATURDAY AND SATURDAY NIGHT...DRIVING WAVE HEIGHTS TO 3-5 FT...WITH ISOLATED 6 FTERS POSSIBLE. THESE ARE MARGINAL SCA CONDITIONS...AND IT IS POSSIBLE A SMALL CRAFT ADVISORY WILL BE NEEDED SATURDAY. ON SUNDAY...HIGH PRESSURE WILL MOVE JUST NORTH OF THE WATERS AND OFF THE MID-ATLANTIC COAST...CAUSING THE GRADIENT TO RELAX AND WINDS TO EASE TO AROUND 10 KTS WHILE VEERING TO THE EAST SUNDAY NIGHT. WINDS WILL REMAIN LIGHT THROUGH THE END OF THE PERIOD...BUT A SUBTLE INCREASE WILL BE NOTED VERY LATE AHEAD OF AN APPROACHING STORM SYSTEM FROM THE WEST. SEAS SUNDAY WILL INITIALLY BE 3-5 FT THANKS TO A SHORT PERIOD NORTHERLY WIND WAVE...BUT WILL FALL TO 1-2 FT LATE WITH A 10 SEC SE SWELL INCREASING. LONG TERM /MONDAY THROUGH TUESDAY/... AS OF 330 AM FRIDAY...LOW PRESSURE SYSTEM WILL STRENGTHEN AND MOVE QUICKLY ACROSS THE SE STATES...REMAINING WEST OF THE WATERS...BEFORE LIFTING NE INTO NEW ENGLAND LATE TUESDAY. THIS WILL DRIVE INCREASING WINDS ON MONDAY UP TO 15-25 KTS WHILE VEERING FROM EAST TO SOUTH...AND THEN INCREASING EVEN FURTHER TO 20-25 KTS FROM THE SW THE FIRST HALF OF TUESDAY. AS THE LOW MOVES OFF TO THE NORTHEAST LATE...ITS COLD FRONT WILL DRAG ACROSS THE WATERS...ACCOMPANIED BY A WIND SHIFT TO THE NW BUT WITH STILL ELEVATED SPEEDS. SEAS WILL BUILD VERY RAPIDLY MONDAY FROM 1-2 FT MONDAY MORNING TO 4-7 FT MONDAY NIGHT...AND THEN POTENTIALLY AS HIGH AS 10 FT TUESDAY WHEN THE LOW MAKES ITS CLOSEST APPROACH. THIS MAY BE SLIGHTLY OVERDONE DUE TO THE SHORT DURATION OF THE STRONGEST WINDS...BUT THE LONG FETCH AT LEAST PRESENTS THE OPPORTUNITY FOR SUCH HIGH SEAS. WAVES WILL FALL QUICKLY BEHIND THE COLD FRONT...BUT MUCH OF THE EARLY WEEK PERIOD WILL FEATURE POOR MARINE CONDITIONS WITH HEADLINES A NEAR CERTAINTY.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
SC...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR SCZ017-023-024-032-033-053-054. NC...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR NCZ087-096-099-105>110. MARINE...NONE.
-- End Changed Discussion --
&& $$ SYNOPSIS...JDW NEAR TERM...REK SHORT TERM...JDW LONG TERM...JDW AVIATION...REK MARINE...REK/JDW

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.