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000
FXUS62 KILM 261014
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
514 AM EST THU FEB 26 2015

.SYNOPSIS...
LOW PRESSURE WILL MOVE OFF TO THE NORTHEAST TODAY BRINGING A SLOW
END TO THE RAINFALL. SOME LIGHT FREEZING RAIN OR FREEZING DRIZZLE
IS POSSIBLE EARLY THIS MORNING FAR INLAND. A WEDGE OF HIGH
PRESSURE WILL BUILD DOWN THE COAST FRIDAY AND THROUGH THE WEEKEND
BRINGING DRIER WEATHER BUT WITH VERY COLD TEMPERATURES. MOISTURE
WILL RETURN EARLY NEXT WEEK BUT WITH MORE SEASONABLE TEMPERATURES.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 430 AM THURSDAY...MAIN PCPN SHIELD WILL BECOME ORIENTED
NORTH AND EAST OF THE FA DURING THE NEXT FEW HOURS. CURRENT PCPN
OVER THE ILM COASTAL AND OFFSHORE WATERS...WILL MOVE NEARLY
PARALLEL TO THE CAROLINA COASTLINES OF THE ILM CWA THIS MORNING.
THIS AREA OF PCPN IS TRACKING AND OCCURRING ALONG THE COASTAL AND
OFFSHORE WATERS WHERE THE COASTAL FRONT/TROF LIES...WHICH IS
PARALLEL TO THE IMMEDIATE CAROLINA COASTS. THE DEEPENING SFC LOW
IS CURRENTLY MOVING ALONG IT THAT IS NOW IN THE VICINITY OF CAPE
FEAR ATTM. VARIOUS COASTAL 88D RADARS INDICATE A MORE CONVECTIVE
LOOK TO THE PCPN OVER THE ADJACENT ATL WATERS DUE TO THE
AVAILABILITY OF INSTABILITY...MAINLY ALOFT...COMPLEMENTS OF THE
MILD 60+ DEGREE SSTS THAT ARE ASSOCIATED WITH THE GULFSTREAM. DO
NOT EXPECT ANY OF THIS CONVECTION TO MOVE ONSHORE.

AS THE SFC LOW FURTHER INTENSIFIES AS IT PUSHES FURTHER NE TOWARD
CAPE HATTERAS THIS MORNING...SOME CAA ADVECTION ON ITS BACKSIDE
WILL OVERSPREAD THE FA UNDER NW-N FLOW. WITH THE BEST UVVS AND
DYNAMICS NORTH OF THE FA AFTER DAYBREAK THU...ANY PCPN THAT FALLS
FOR THE REMAINDER OF THE DAY WILL BE VERY LIGHT RAIN OR DRIZZLE.
THE QUESTION RESIDES...WILL THERE BE ENOUGH SFC BASED COLD AIR
AVBL ACROSS THE WINTER WX ADV OUTLINE TO SUPPORT LIGHT FREEZING
RAIN OR LIGHT FREEZING DRIZZLE...PRIOR TO THE PCPN COMPLETELY
COMING TO AN END LATE THIS MORNING. LOOKING AT VARIOUS MODEL BUFR
SOUNDINGS AND PROGS...THERE IS JUST ENOUGH SUPPORT FOR COLD AIR TO
BECOME AVBL FOR LIGHT FREEZING PCPN ACROSS THE CURRENT WWA
OUTLINE. THEREFORE...DID NOT MAKE ANY CHANGES TO THE WWA ISSUED
MUCH EARLIER THIS MORNING. ONCE SFC BASED TEMPS INCREASE ABOVE 32
BY LATE THIS MORNING ACROSS THE WWA AREA...THE THREAT FOR FREEZING
PCPN WILL COME TO AN END.

FOR THE REMAINDER OF THE AFTN AND TONIGHT...PLENTY OF LOW LEVEL
MOISTURE TO EXIST FROM THE SFC THRU 8H. THUS...THE FA WILL BE
LOOKING AT A LOW STRATIFORM DECK OF CLOUDS ALL DAY BASICALLY AND
INTO THIS EVENING. AM NOT QUITE A BELIEVER THAT ENOUGH MIXING
FROM THE VERTICAL WILL CLEAR SKIES OUT LATER THIS EVENING AND
TONIGHT...THUS WILL KEEP A VARIABLE OR MOSTLY CLOUDY SKY INTO
TOMORROW MORNING. AS FOR TEMPS...LEANED TOWARD THE LOWER SIDE OF
THE AVAILABLE MODEL MOS GUIDANCE.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...DRY BUT COLD FOR THE SHORT TERM AS A WEDGE
OF HIGH PRESSURE BECOMES ENTRENCHED ALONG THE EAST COAST. THIS HIGH
DEVELOPS BEHIND A COLD FRONT FROM THURSDAY...AND IS INTENSIFIED BY
PERSISTENT CONFLUENCE ALOFT. FORECAST PROFILES SUGGEST A LOT OF
SUNSHINE FRI/SAT...BUT THESE STRONG WEDGES ARE FREQUENTLY
ACCOMPANIED BY A LOT OF LOW-LEVEL MOISTURE ON THE NE FLOW...WHICH
MANIFEST AS LOW LEVEL CLOUDS. THUS...WILL NOT BE AS OPTIMISTIC AS
THE GUIDANCE WITH SUNSHINE FOR THE WEEKEND. IT WILL BE DRY HOWEVER.
THIS IS GOOD BECAUSE TEMPERATURES WILL BE SOLIDLY 15-20 DEGREES
BELOW NORMAL...WITH SATURDAY THE COLDER DAY. HIGHS FRIDAY WILL
STRUGGLE INTO THE LOW-TO-MID 40S ON FRIDAY...AND A FEW DEGREES
COOLER ON SATURDAY WHEN SOME PLACES WON`T EVEN CRACK 40. LOWS BOTH
NIGHTS WILL BE SIMILARLY COLD...FALLING INTO THE 20S MOST
LOCATIONS...WITH A FEW MORE LOW 30S SATURDAY NIGHT AS CLOUD COVER
INCREASES.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
AS OF 300 AM THURSDAY...PATTERN CHANGE DEVELOPS...FINALLY...AS BROAD
RIDGING ENVELOPS THE SOUTHEAST. THERE IS CONSIDERABLE UNCERTAINTY
INTO HOW LONG THIS RIDGING WILL PERSIST...AND 2 SEPARATE COLD FRONTS
NEXT WEEK COULD QUICKLY BRING US BACK TO BELOW NORMAL TEMPS...BUT
FOR THIS FORECAST WILL BE SOMEWHAT OPTIMISTIC.

ONE LAST WELL BELOW NORMAL DAY EXPECTED SUNDAY AS THE SURFACE WEDGE
SLOWLY BEGINS TO BREAK DOWN IN RESPONSE TO MID-LEVEL DEVELOPING
RIDGE. AT THE SAME TIME...A COLD FRONT WILL APPROACH FROM THE
NW...AND MOISTURE WILL INCREASE WITHIN THE COLUMN. THERE DOES NOT
APPEAR TO BE A LOT OF FORCING FOR SHOWERS SUNDAY...BUT THE INHERITED
INCREASING POP SUNDAY NIGHT SEEMS WARRANTED. WARMER TEMPS MONDAY
IMMEDIATELY AHEAD OF THE COLD FRONT IN A PRE-FRONTAL AIR MASS WILL
BE ACCOMPANIED BY BETTER SHOWER CHANCES THANKS TO A SHORTWAVE MOVING
OVERHEAD. THIS FRONT WILL BECOME ALIGNED PARALLEL TO THE FLOW LATE
MONDAY INTO TUESDAY...AND WILL STALL IN THE VICINITY BEFORE LIFTING
BACK NORTH BY WEDNESDAY. THIS LEAVES TUESDAY AS THE BIGGEST QUESTION
MARK WITH RESPECT TO TEMPS...BUT EXPECT JUST BELOW NORMAL TEMPS WITH
CONTINUED POTENTIAL FOR SHOWERS. A MORE SIGNIFICANT WARMUP IS ON TAP
FOR WEDNESDAY ON RETURN FLOW AND CONTINUED MID-LEVEL RIDGING...BUT
UNSETTLED WEATHER WILL PERSIST AS ANOTHER COLD FRONT APPROACHES THE
AREA.

&&

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
AS OF 06Z...MODERATE TO HEAVY PRECIPITATION CONTINUES ACROSS THE
TERMINALS EARLY THIS THU AM...WITH ALL TERMINALS FLUCTUATING
WITH MVF AND IFR...AND EVEN OCCASIONALLY VFR CONDITIONS. FORECAST
THAT! RELATIVELY HIGH CONFIDENCE THAT THE AREA TERMINALS WILL BE
TOTALLY DOMINATED BY IFR THROUGH DAYBREAK FROM BOTH CEILINGS AND
VSBY...AND MAINLY FROM CEILINGS THERE-AFTER THRU SUNSET THU.
HAVE REMOVED ALL MENTION OF -SN AND -PL FROM THE FORECAST AS MODEL
SOUNDINGS AND OOZ LOCAL RAOBS AND MODEL DATA INDICATE A DEEP WARM
LAYER IN THE LOWER LEVELS. AFTER THE PASSAGE OF THE LOW TO THE
EAST OF THE ILM CWA...WINDS BACK TO THE NW-N WITH A RETURN OF SOME
COLD AIR AT THE SFC. MAY BE COLD ENOUGH TO INCLUDE A PERIOD OF
FZRN OR FZDL TOWARD DAYBREAK...AND UP TO SEVERAL HOURS
THERE-AFTER. ALL PCPN SHOULD END BY MID TO LATE MORNING...WITH
THE LOWER LEVELS REMAINING MOIST DOWN TO THE SFC...RESULTING IN A
LOW CLOUD DECK THRUOUT DAYLIGHT THU...AND PARTIALLY INTO THE
EVENING BEFORE SOME DRY AIR MIXES IN TO RAISE THE LOW STRATIFORM
CEILINGS. WINDS INITIALLY WILL STAY ACTIVE AND GUSTY UP TO 20 KT
FROM THE N-NE... THEN SLOWLY BACK TO NW-NNW AND DIMINISH LATER
TODAY INTO TONIGHT.

EXTENDED OUTLOOK...VFR CONDITIONS FRIDAY THRU SATURDAY...MVFR/IFR
POSSIBLE LATE SUNDAY INTO MONDAY.

&&

.MARINE...
.NEAR TERM /THROUGH TONIGHT/...
AS OF 630 PM WEDNESDAY...THE ONLY CHANGE TO THE FORECAST WAS TO SLOW
DOWN THE RATE OF INCREASE IN FORECAST SEA HEIGHTS OVERNIGHT. OUR
LOCAL SWAN WAVE MODEL HAS A WELL-KNOWN BIAS OF INCREASING SEAS MUCH
TOO QUICKLY IN PERIODS OF STRENGTHENING WIND. NO OTHER SIGNIFICANT
CHANGES ARE NECESSARY. DISCUSSION FROM 300 PM FOLLOWS...

LOW PRESSURE WILL MOVE OUT OF THE GULF OF MEXICO THIS EVE AND THEN
UP THE CAROLINA COAST...INTENSIFYING OFF THE NORTH CAROLINA COAST
TOWARD DAYBREAK AND ON THU. THE PRESSURE GRADIENT IS EXPECTED TO
BECOME SUFFICIENTLY TIGHT TO SUPPORT 20 TO 25 KT WINDS. THE
DIRECTION WILL BE NE THROUGH THE EVE...BACKING TO THE N OVERNIGHT.
SEAS WILL RESPOND TO THE INCREASING WINDS...BUILDING UP TO 6 TO 9
FT...10 FT SEAS ARE POSSIBLE AROUND FRYING PAN SHOALS. SEAS WILL BE
LOWER ACROSS THE VERY NEAR SHORE WATERS.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 300 AM THURSDAY...WEDGE OF HIGH PRESSURE WILL DEVELOP AND
STRENGTHEN ALONG THE COAST THROUGH THE SHORT TERM. THIS PRODUCES
PERSISTENT N/NE WINDS BOTH FRIDAY AND SATURDAY...WITH SPEEDS
INCREASING INTO SATURDAY WHEN THE WEDGE BECOMES MOST INTENSE. SPEEDS
OF 10-15 KTS EARLY FRIDAY WILL RISE GRADUALLY...BECOMING STRONGEST
ON SATURDAY WHEN SPEEDS WILL REACH 20-25 KTS. VERY LATE SATURDAY
NIGHT WINDS WILL BEGIN TO EASE AS THE WEDGE STARTS TO BREAK DOWN.
THE HIGHEST SEAS WILL OCCUR LATE FRIDAY NIGHT AND THROUGH MUCH OF
SATURDAY...WHEN 4-6 FT SEAS WILL BE COMMON...AND AN SCA IS LIKELY.
OTHERWISE...SEAS WILL BE 2-4 FT BOTH BEFORE THE SMALL CRAFT
CONDITIONS...AND AGAIN AFTER IT SATURDAY NIGHT.

LONG TERM /SUNDAY THROUGH MONDAY/...
AS OF 300 AM THURSDAY...WEAKENING WEDGE JUST INLAND FROM THE COAST
WILL LEAVE EASING NE WINDS MUCH OF SUNDAY...EVENTUALLY VEERING TO
THE SOUTH AROUND 10 KTS BY MONDAY MORNING. WIND DIRECTION WILL VEER
FURTHER TO THE SW AND INCREASE TO 10-15 KTS MONDAY AHEAD OF A COLD
FRONT...BUT THEN SHIFT ABRUPTLY BACK TO THE NORTH AT THE END OF THE
PERIOD BEHIND ITS PASSAGE. WAVE HEIGHTS THROUGH THE EXTENDED WILL
HOVER AROUND 2-4 FT...BUT A NE WIND CHOP WILL DOMINATE THE SPECTRUM
ON SUNDAY...WHILE A SOUTHERLY WIND WAVE WILL DEVELOP ON MONDAY.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR SCZ017-023-
     024.

NC...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR NCZ087-096-
     105.

MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR AMZ250-
     252-254-256.

&&

$$
SYNOPSIS...JDW
NEAR TERM...DCH
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...DCH