National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS62 KILM 101504
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
1004 AM EST TUE DEC 10 2013

.SYNOPSIS...
A COLD FRONT WILL SLOWLY MOVE ACROSS THE AREA TODAY BRINGING
WIDESPREAD LIGHT RAINFALL. DRY AND COOL CONDITIONS WILL DEVELOP
WEDNESDAY AND CONTINUE THROUGH FRIDAY. THE WEEKEND IS LOOKING MORE
AND MORE UNSETTLED AS A STORM SYSTEM DEVELOPS IN THE SOUTHEAST.
COOLER AND DRIER CONDITIONS ARE EXPECTED EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 930 AM TUESDAY...COMPLEX WEATHER SCENARIO FOR TODAY WITH LOW
PRESSURE SYSTEM OVER THE CAROLINAS. WARM AIR STREAMING NORTHWARD
AHEAD OF COLD FRONT OVER WESTERN CAROLINAS. TEMPS ALREADY HIT 70
AT WILMINGTON AIRPORT AND WIDESPREAD 60S AS WARMER AIR IS MIXING
DOWN WITH A DEEPER AND INCREASING WARM AND MOIST SOUTHERLY FLOW.
DENSER COLDER AIR HELD ON OVER CENTRAL TO NORTHERN
CAROLINAS...JUST UPSTREAM OF FORECAST AREA. THE WARM AIR ALOFT
RIDING OVER COLD AIR INLAND PRODUCING DECENT ISENTROPIC LIFT WITH
STEEP INVERSION IN PLACE BASICALLY JUST WEST AND NORTH OF AREA
WHERE WEDGE HELD ON. TEMPS WILL PEAK THIS MORNING BUT CLOUDS...PCP
WILL KEEP TEMPS FROM RISING TOO MUCH IN MOST PLACES AND THEN COLD
FRONT WILL PUSH THROUGH BY EARLY TO MID AFTN. TEMPS AT H85 WILL
RISE UP TO 12C BY NOON TIME AND THEN WILL PLUMMET THROUGH THIS
AFTN DOWN CLOSE TO 4C BY MIDNIGHT.

COOLER WATERS KEEPING TEMPS MUCH COOLER...CLOSER TO 60...ALONG
THE BEACHES AND UP THROUGH BRUNSWICK COUNTY WHERE ON SHORE FLOW IS
MAXIMIZED. THIS IS ALSO LEADING TO ANOTHER ROUND OF SEA FOG AS
WARMER MOISTER AIR JUST ABOVE THE SURFACE IS MOVING ATOP THE COOLER
WATERS. ISSUED SPECIAL WEATHER STATEMENT TO ADDRESS LOCALIZED FOG
OVER SHELF WATERS SOUTH MAINLY ADVECTIN FROM SOUTH OF CAPE FEAR ON
SHORE OVER BRUNSWICK COUNTY.

BEST ISENTROPIC LIFT WILL REMAIN JUST NORTH AND WEST OF AREA
WHERE COOLER AIR IS LOCATED BUT SHOULD SEE MORE CONVECTIVE TYPE
PCP IN WARM AND MORE UNSTABLE AIR MASS AHEAD OF FRONT. LLJ UP TO
55 KTS PUMPING PLENTY OF WARM AND MOIST AIR AHEAD OF COLD FRONT. CONVECTIVE
INDICES LOOK LIKE WE COULD SEE SOME LOW TOP CONVECTION AND
POSSIBLY A RUMBLE OF THUNDER. BEST LIFT SHOULD COME JUST AHEAD OF
COLD FRONT THROUGH THIS AFTERNOON LEAVING A NARROW WINDOW BUT MAY
INCLUDE MENTION OF ISO THUNDER IN GRIDS. SFC BASED CAPE VALUES
REACH UP TO 600 JKG. MAY SEE MORE STABLE MARINE LAYER COME INTO
PLAY AS STORMS MOVE CLOSER TO THE COAST...BUT EXPECT SHOWERS AHEAD
OF FRONT THROUGH EARLY AFTERNOON.

THE COLD FRONT BACK TOWARD THE MOUNTAINS THIS MORNING WILL GET A
PUSH FROM MID TO UPPER TROUGH BY MID AFTERNOON AND SHOULD PROGRESS
THROUGH THE I-95 CORRIDOR AROUND 1PM AND REACH THE COAST BY 3 PM. PLENTY
OF COLD AND DRY AIR WILL ADVECT IN BEHIND FRONT AND SCOUR OUT ALL
THE LOW CLOUDS...FOG AND ANY SHOWERS OR PCP ACROSS THE AREA. THIS
WILL LEAD TO FALLING TEMPS ACROSS THE AREA THROUGH THIS EVENING.

AS A STRONG COLD SURGE BARRELS SOUTHEAST ACROSS THE EASTERN
CAROLINAS A STRONG COLD ADVECTION REGIME SETS UP WITH ABOUT A 40
DEGREE DROP IN BOTH TEMPS AND DEWPOINT TEMPS BY MORNING AS COLD
AND DRY AIR COMES RUSHING IN. CLEARING SKIES OVERNIGHT WILL COMBINE
WITH CONTINUED COLD ADVECTION TO ALLOW MINIMUM TEMPERATURES TO DIP
INTO THE LOWER TO MID 30S.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 3 AM TUESDAY...THE MID LEVEL PATTERN WILL CONSIST OF AN INITIAL
WESTERLY FLOW TRANSITIONING INTO MORE OF A NORTHWEST FLOW THURSDAY.
THE ONLY FORECAST DILEMMA IS TEMPERATURES AS SURFACE HIGH PRESSURE
AND PRECIPITABLE WATER VALUES LESS THAN ONE QUARTER INCH KEEP EVEN
CLOUDS OUT OF THE MIX FOR THE MOST PART.

A SECONDARY SHORTWAVE EMBEDDED IN THE MEAN FLOW WILL REINFORCE THE
COLD AIR THURSDAY WITH 850MB VALUES ACTUALLY DROPPING TO JUST BELOW
ZERO DEGREES C. THE TIMING OF THE COLD AIR ADVECTION IS CRITICAL AS
THE MET IS A LITTLE QUICKER AND HENCE HIGH TEMPERATURES IN THE
GUIDANCE BULLETINS ARE ABOUT A CATEGORY COOLER. THE FORECAST
CONTINUES TO OPT FOR A BLEND. FRIDAY MORNING WILL BE QUITE COOL WITH
MOST AREAS SEEING MID TO UPPER 20S.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 3 AM TUESDAY...THE MEDIUM RANGE GUIDANCE APPEARS TO BE COMING INTO
BETTER AGREEMENT WITH THE SCENARIO FOR THE WEEKEND. A SOMEWHAT DEEP
ALBEIT PROGRESSIVE MID LEVEL TROUGH WILL MOVE OUT FROM THE SOUTHWEST
AND ATTEMPT TO PHASE WITH A MODEST SYSTEM TO THE NORTH. THIS ALLOWS
A COMPLEX AREA OF LOW PRESSURE TO DEVELOP IN THE SOUTHEAST AND MOVE
UP THE COAST...EVENTUALLY REDEVELOPING OFF THE DELMARVA AND
DEEPENING. THE GFS CONTINUES TO BE A LITTLE FASTER OF THE GUIDANCE
AND HAVE INCREASED POPS TO MATCH ADJACENT OFFICES BETTER BUT OVERALL
THE LIONS SHARE OF POPS/QPF WILL OCCUR SATURDAY INTO SUNDAY MORNING.
HAVE TRIMMED BACK POPS FOR LATER SUNDAY FOR THE SAME REASONS. NO
CHANGES TO TEMPERATURE FORECAST.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
AS OF 12Z...AN AREA OF PRE-FRONTAL SHOWERS IS ALONG THE I-95
CORRIDOR...MOVING SLOWLY EAST. THE HRRR MODEL HAS THIS BATCH OF
SHOWERS MOVING OUR OF THE REGION LATER THIS MORNING...REPLACE WITH
ANOTHER BATCH OF CONVECTION ALONG THE FRONT BY EARLY AFTERNOON.
CONDITIONS AHEAD OF THE FRONT WILL LIKELY BOUNCE AROUND BOTH
VISIBILITIES AND CEILINGS. FRONT WILL MOVE THROUGH THE INLAND
TERMINALS BY EARLY AFTERNOON...THE COAST BY LATE AFTERNOON. POST
FRONTAL...EXPECT A WIND SHIFT TO THE NORTH NORTHWEST...GUSTY WITH
IMPROVING CONDITIONS. AN MVFR CEILING MAY BRIEFLY
OCCUR...PREDOMINATELY VFR THROUGH THE END OF THE FORECAST PERIOD.

EXTENDED OUTLOOK...INCREASING CONFIDENCE FOR VFR WEDNESDAY THROUGH
FRIDAY. SHOWERS POSSIBLE SATURDAY AHEAD OF AN APPROACHING LOW
PRESSURE SYSTEM.

&&

.MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/...
AS OF 930 AM TUESDAY...SEA FOG DEVELOPED ONCE AGAIN AS WARM AIR
JUST ABOVE THE SURFACE WAS MOVING OVER COOL SHELF WATERS....MORE
WIDESPREAD JUST SOUTH OF BRUNSWICK. ISSUED SPS FOR NOW BUT MAY
HAVE TO ISSUE DENSE FOG ADVISORY. SMALL CRAFT ADVISORY REMAINS IN
EFFECT TODAY AS WINDS AND SEAS INCREASE IN ADVANCE OF A STRONG
COLD FRONT. WINDS WILL TURN NORTHWEST THIS AFTERNOON AS THE FRONT
MOVES ACROSS THE WATERS...WITH LIMITED FETCH CAUSING NEAR- SHORE
SEAS TO SUBSIDE TO BELOW SMALL CRAFT ADVISORY CRITERIA TONIGHT.
CURRENT OBS SHOW CONDITIONS OVER THE COASTAL WATERS ARE STILL ON
THE BENIGN SIDE...WITH SW WINDS OF ONLY AROUND 5 KTS...AND 3 TO 4
FT SEAS.

SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
AS OF 3 AM TUESDAY...OVERALL CONDITIONS NOT TOO BAD CONSIDERING HIGH
PRESSURE WILL BE MOVING IN FROM THE WEST/NORTHWEST. FOR
WEDNESDAY...WINDS WILL BE FROM THE NORTHEAST AROUND TEN KNOTS AND
MAY BE LOWER AS THE PATTERN BRIEFLY RELAXES LATE IN THE DAY. COLD
AIR ADVECTION DEVELOPS AGAIN THURSDAY WHICH WILL KICK WINDS UP TO
15-20 KNOTS FROM THE NORTH. SEAS WILL BE REFLECTIVE OF THE
WINDS...1-3 FEET MOST OF WEDNESDAY INTO EARLY THURSDAY INCREASING
WITH THE WINDS TO 3-5 FEET LATE IN THE PERIOD.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 3 AM TUESDAY...EXPECT RELATIVELY BENIGN WINDS AND SEAS FOR
FRIDAY AS THE CENTER OF HIGH PRESSURE MOVES OVERHEAD. WINDS
INCREASE AND VEER MORE TO THE SOUTHEAST AS A STORM SYSTEM DEVELOPS
IN THE SOUTHEAST. STILL A LOT OF DETAILS TO IRON OUT WITH THIS
SYSTEM BUT OVERALL MARINERS SHOULD EXPECT THIS TREND OF INCREASING
WINDS AND SEAS FOR SATURDAY.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 7 PM EST THIS EVENING FOR AMZ250-
     252-254-256.

&&

$$
SYNOPSIS...
NEAR TERM...RGZ
SHORT TERM...SHK
LONG TERM...SHK
AVIATION...DL
MARINE...SHK