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 262345
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
645 PM EST THU FEB 26 2015

.SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE WILL BUILD ACROSS THE AREA THROUGH SATURDAY AND
BEGIN TO TAKE ON A WEDGE SIGNATURE...LOCKING THE COLD AIR ACROSS
THE CAROLINAS. THIS HIGH WILL MOVE OFFSHORE SATURDAY. THE NEXT
CHANCE OF PRECIPITATION WILL COME EARLY NEXT WEEK IN ASSOCIATION
WITH A COLD FRONT. NO RISK OF WINTRY PRECIPITATION EXPECTED NEXT
WEEK...AS MUCH WARMER TEMPERATURES ARRIVE THROUGH EARLY MARCH.
-- End Changed Discussion --

&&

.NEAR TERM /THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 645 PM THURSDAY...THE MOST RECENT NEAR TERM DATA BRINGS A
SLOWER DROP IN HOURLY TEMPERATURES THROUGH EVENING...LIKELY IN
PART TO SUBLIMATION OCCURRING OFF THE UPSTREAM SNOW PACK..THUS
KEEPING DEWPOINT VALUES LOCKED AROUND 32 DEG F GIVE OR TAKE A
DEGREE EVEN NORTHWARD INTO CENTRAL NORTH CAROLINA. THIS REQUIRED
A DEGREE OR 2 BUMP UPWARD IN MINIMUM TEMPERATURES INTO DAYBREAK
BUT STILL BELOW FREEZING MOST AREAS AND RE-FREEZING OF WET AREAS
AND THE BLACK ICE POTENTIAL REMAINS. NO OTHER SIGNIFICANT CHANGES
AND PLENTIFUL CLOUDS ABOUT THE AREA ARE ALSO AIDING IN SLOW TEMP
DROPS. THE PREVIOUS DISCUSSION FOLLOWS.

PATCHY BLACK ICE AND AREAS OF FREEZING FOG WILL INCREASE THE RISK
FOR HAZARDOUS TRAVELING CONDITIONS LATER TONIGHT AND INTO FRI
MORNING. THE GROUND IS COLD AND WET AND SIGNIFICANTLY LOWER
VISIBILITIES WILL BE SLOW TO ARRIVE. AT THE SAME TIME...TEMPS WILL
BE DROPPING BELOW FREEZING MID TO LATE EVE OR OVERNIGHT. THESE
CONDITIONS INCREASE THE PROSPECTS FOR LOW CEILINGS IN STRATUS AND
POOR VISIBILITIES IN FOG AND FREEZING FOG. VISIBILITIES OF LESS
THAN 2 MILES IN FOG MAY BECOME QUITE COMMON AND LOCALLY NEAR A
QUARTER-MILE. AN SPS HAS BEEN ISSUED TO ADDRESS THESE HAZARDS.

LOW PRESSURE WELL EAST OF THE VIRGINIA CAPES WILL CONTINUE TO MOVE
TO THE NE THROUGH TONIGHT. THE CENTER OF COLD HIGH PRESSURE ACROSS
THE NORTHERN PLAINS WILL SLOWLY DROP INTO THE MISSOURI VALLEY BY
MORNING. DRY AIR IS SCARCE AND IN FACT...MUCH OF THE EASTERN THIRD
OF THE NATION REMAINS CLOUDY. A PRONOUNCED SUBSIDENCE INVERSION
SHOULD BE ABLE TO LOCK IN THE THICK CLOUDS INTO FRI MORNING EVEN AS
MUCH DRIER AIR ARRIVES ABOVE 5-6 KFT.

NORTHERLY TRAJECTORIES WILL CONTINUE THROUGH THE NIGHT. THIS IS A
PARTICULARLY COLD FLOW GIVEN THE FRESH SNOW-PACK NOT TOO FAR TO OUR
N. THUS...CONFIDENCE IN BELOW FREEZING TEMPS TONIGHT IS HIGH.
HOWEVER...THE SLOW ARRIVAL OF SIGNIFICANTLY LOWER DEWPOINTS MAY KEEP
TEMPS FROM GETTING QUITE AS COLD AS THEIR POTENTIAL. AT THIS TIME...
WE ARE EXPECTING LOWS MAINLY IN THE MID AND UPPER 20S.
-- End Changed Discussion --

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...A BROAD ZONAL FLOW WILL BE IN PLACE THROUGH THE
PERIOD. AT THE SURFACE...MODERATING ARCTIC HIGH PRESSURE WILL BE IN
PLACE THROUGH EARLY SATURDAY. AFTER THIS SOME DEVELOPING CONFLUENCE
IN THE MID LEVEL PATTERN ALLOWS A WEDGE TO BUILD DOWN INTO THE AREA.
VERY SHALLOW ARCTIC AIR WILL ONCE AGAIN SURGE INTO THE AREA. WITH
THE AIRMASS CONTINUING TO BE VERY DRY...POPS SHOULD NOT BE AN ISSUE
ALTHOUGH THE TEMPERATURE FORECAST IS CHALLENGING.

FRIDAY AND EVEN SATURDAY ARE FAIRLY STRAIGHTFORWARD. GUIDANCE HAS
TRENDED UP SLIGHTLY FOR FRIDAY WITH THE OUTSIDE POSSIBILITY OF 50
DEGREES IN WILMINGTON. BOTH THE MET AND MAV HAVE 49. WITH THE
POSSIBILITY OF AT LEAST SOME PARTIAL CLEARING MIDDLE 20S SEEM OK FOR
SATURDAY MORNING. SATURDAY WILL BE MUCH COOLER VS FRIDAY AS THE
REINFORCING SHOT OF DRY ARCTIC AIR PUSHES IN. IT MAY BE A STRUGGLE
TO REACH 40 IN NORTHERN AREAS. FINALLY SUNDAY MORNING GUIDANCE IS IN
TWO DISTINCT CAMPS WITH THE MET SOME FIVE TO TEN DEGREES WARMER VS
THE MAV. I LEANED SLIGHTLY TOWARD THE MORE MODIFIED MET CITING
OVERCAST SKIES...WHICH ARE DEPICTED BY THE GUIDANCE USUALLY WARRANTS
GUIDANCE BEING ON THE COOL SIDE.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
AS OF 245 PM THURSDAY...SUNDAY LOOKS CLOUDY AND COOL BUT LARGELY
RAIN-FREE AS WEDGE OF HIGH PRESSURE STRUGGLES TO HOLD ON ACROSS THE
CAROLINAS, ITS MAIN CENTER DRIFTING OFF THE DELMARVA COAST.  THE
WEDGE LIFTS OUT SUNDAY  NIGHT AS THE HIGH MORE OR LESS BIFURCATES.
BY 12Z MONDAY ONLY THE EASTERN/OFFSHORE CENTER REMAINS AND A COLD
FRONT WILL BE BEARING DOWN ON THE AREA FROM THE NW. RAIN CHANCES
WILL SLOWLY RISE SUNDAY NIGHT AND NON-DIURNAL TEMPERATURE TRENDS MAY
BE POSSIBLE. AS SEEN YESTERDAY WITH RESPECT TO SUNDAY`S HIGHS MEX
GUIDANCE IS NOW 10 DEGREES COOLER FOR MONDAY AS THERE IS LITTLE
OPPORTUNITY FOR SOLAR INSOLATION TO AID IN THERMAL ADVECTION. EVEN
SO MONDAY WILL END UP BEING CLOSER TO CLIMO HIGHS THAN THE AREA HAS
SEEN IN SOME TIME MAKING UPPER 50S FEEL WELCOME. WILL TRIM SLIGHTLY
TOWARDS THOSE VALUES. TUESDAY ON THE OTHER HAND NOW DOESN`T LOOK
QUITE AS COLD AND WEDGE-LIKE BEHIND THE MONDAY COLD FRONT. ALTHOUGH
ANOTHER CLOUDY DAY WITH RAIN CHANCES TUESDAY HIGHS MAY BE CLOSE TO
THOSE OF MONDAY. THIS WEAK WEDGE WASHES OUT ON WEDNESDAY WITH YET
ANOTHER BOUNDARY EN ROUTE FROM POINTS NORTH AND WEST. A DEEP AND
MODERATELY STRONG SOUTHWESTERLY FLOW DEVELOPS AND WE SHALL FINALLY
SEE AN UNSEASONABLY WARM AFTERNOON DESPITE WHAT MAY BE A RATHER
CLOUDY DAY. IN FACT BECAUSE OF THE CLOUDS I`D LOVE TO BELIEVE THE
MEX NUMBERS THAT SHOW ALL AREAS AWAY FROM THE IMMEDIATE COAST
HITTING A HIGH OF 80 OR BETTER-BUT I DON`T. WITH 850MB TEMPS AROUND
12C AND LAPSE RATES A BIT STEEPER THAN MOIST ADIABATIC LOW 70S SEEM
MUCH MORE PROBABLE.

&&

.AVIATION /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
AS OF 00Z...EXPECT MVFR/POSSIBLE IFR DUE TO LOW CIGS AND POSSIBLE AREAS
OF FOG TONIGHT INTO THE OVERNIGHT HOURS...WITH CONDITIONS GRADUALLY
IMPROVING TO VFR AS HIGH PRESSURE CONTINUES TO SLOWLY BUILD IN.

WITH NORTHERLY WINDS AOB 10 KTS...WIDESPREAD LOW CIGS AS SEEN FROM
LATEST 11U-3.9U SATELLITE ARE CREATING MAINLY MVFR AT THE TERMINALS
THIS EVENING...WITH THE EXCEPTION OF KCRE AND KLBT WHERE THERE ARE
SOME BREAKS IN THE CLOUDS. EXPECT THE TREND OF MVFR WITH
INTERMITTENT PERIODS OF VFR POSSIBLE THROUGH THE EARLY OVERNIGHT
HOURS...WITH EVEN LOWER CIGS AND/OR PATCHES OF FOG TO CREATE IFR.
CONFIDENCE REMAINS LOW...THUS HAVE KEPT TEMPO GROUPS IN GOING
FORECAST.

EXPECT A GRADUAL IMPROVEMENT TO VFR ACROSS
THE AREA LATE OVERNIGHT WELL INTO FRIDAY AS HIGH PRESSURE CONTINUES
TO BUILD INTO THE AREA. NORTHEAST WINDS AROUND 10 TO 12 KTS WILL
PREVAIL ON FRIDAY.

EXTENDED OUTLOOK...MVFR/IFR POSSIBLE LATE SUNDAY INTO MONDAY.
OTHERWISE EXPECT VFR.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
.NEAR TERM /THROUGH TONIGHT/...
AS OF 645 PM THURSDAY...ADVISORY IN EFFECT ONLY FOR NC AS WINDS
AND SEAS CONTINUE TO TREND DOWNWARD. THE PRESSURE GRADIENT WILL
CONTINUE TO EASE...BUT SWELL ENERGY WAS HELPING TO KEEP SEAS
ELEVATED. SEAS WERE 4.5 FT AT WILMINGTON HARBOR AND 7.5 FT AT THE
FRYING PAN SHOALS BUOY. THUS...EXTENDING THE ADVISORY FOR THE
NORTHERN WATERS BY SEVERAL HOURS. WE DO EXPECT SEAS WILL DROP
BELOW 6 FT THROUGHOUT DURING THE EARLY TO MID EVE HOURS. THE WIND
DIRECTION WILL REMAIN FROM THE NORTH WITH A SLIGHT INCREASE IN
WIND SPEEDS AS A NORTHERLY SURGE MOVES DOWN THE COAST...UP TO 15
TO 20 KT.


SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
AS OF 245 PM THURSDAY...A NORTHERLY COMPONENT TO THE WINDS WILL BE THE
COMMON FACTOR ACROSS THE COASTAL WATERS FOR THE SHORT TERM PERIOD.
FOR FRIDAY WINDS WILL MAINTAIN A MOSTLY NORTH DIRECTION WITH SPEEDS
OF 15-20 KNOTS. SOME VEERING TO TO NORTHEAST CAN BE EXPECTED
OVERNIGHT FRIDAY AND INTO SATURDAY AS MORE OF A WEDGE CONFIGURATION
DEVELOPS. WITH A SECONDARY SURGE OF SHALLOW COLD AIR WINDS WILL
INCREASE IN MAGNITUDE TO AROUND 20 KNOTS. SEAS WILL RISE FROM 2-4
FEET FRIDAY TO 3-6 FEET EARLY SATURDAY AND MAINTAIN THESE HEIGHTS
THROUGH LATE IN THE PERIOD. AN EXTENDED SMALL CRAFT ADVISORY WILL
PROBABLY BE IN ORDER.

LONG TERM /SUNDAY THROUGH TUESDAY/...
AS OF 245 PM THURSDAY...A WEDGE OF HIGH PRESSURE OVER THE CAROLINAS
WILL BRING A NORTHEASTERLY FLOW OVER THE WATERS ON SUNDAY. THE
GRADIENT WILL ONLY BE MODERATE AT BEST SO DESPITE SOME SWELL ENERGY
MIXING IN WITH THE WIND WAVES OVERALL SEAS WILL BE FAIRLY TYPICAL
FOR THE TIME OF YEAR WITH NO HEADLINES OR FLAGS IN EFFECT.
TROUGHINESS WILL DEVELOP BETWEEN THIS WEDGE AND THE WEST ATLANTIC
HIGH SUNDAY NIGHT AND THE FORMER AIRMASS SHOULD BE GONE BY MONDAY.
THIS WILL BRING LIGHT WINDS THAT WILL TURN TO THE SW EARLY MONDAY
FOLLOWED BY A VEER TO THE NW MIDDAY MONDAY OR MONDAY AFTERNOON AS A
WEAK COLD FRONT PUSHES THROUGH THE REGION. SIGNIFICANT WAVE HEIGHT
MAY NOT CHANGE MUCH AND DOMINANT PERIOD MAY SHORTEN SOME AS SWELL
ENERGY ABATES. NORTHEASTERLY FLOW RETURNS TUESDAY AS ANOTHER WEAK
HIGH WEDGES UP AGAINST THE EAST FACE OF THE APPALACHIANS AND AN AXIS
OF HIGH PRESSURE DEVELOPS INTO THE CAROLINAS. SLIGHT INCREASE IN
SWELL AND WIND WAVE COULD BUMP SEAS UP BUT STILL NO
HAZARDS/HEADLINES.
-- End Changed Discussion --

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
SC...NONE.
NC...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR AMZ250-
     252.
-- End Changed Discussion --

&&

$$

NEAR TERM...RJD/MJC
SHORT TERM...SHK
LONG TERM...MBB
AVIATION...SGL