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

000
FXUS62 KILM 210726
AFDILM

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WILMINGTON NC
326 AM EDT TUE APR 21 2015

.SYNOPSIS...
A COLD FRONT WILL MOVE OFF THE COAST AROUND DAYBREAK. DRY AND
SEASONABLE HIGH PRESSURE WILL BUILD ACROSS THE AREA TODAY AND
WEDNESDAY. ANOTHER COLD FRONT WILL CROSS THE COAST EARLY THURSDAY
FOLLOWED BY MORE SEASONABLE WEATHER FRIDAY. A STORM SYSTEM MAY
AFFECT THE AREA SATURDAY. COOLER HIGH PRESSURE WILL FOLLOW INTO
EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM TUESDAY...FOR THE FIRST TIME IN RECENT MEMORY THERE IS
VIRTUALLY NO CHANCE FOR RAIN TODAY. A COLD FRONT IS MAKING ITS WAY
EAST ACROSS THE AREA CURRENTLY. THE BOUNDARY WILL REACH I-95 SHORTLY
AND SHOULD BE MOVING ACROSS THE BEACHES BY DAYBREAK. MUCH DRIER AIR
WILL BUILD IN ON WESTERLY WINDS...DROPPING RELATIVE HUMIDITY DOWN
TOWARD 30 PERCENT THIS AFTERNOON. DESPITE 850 MB TEMPS FALLING TO
+5C TO +7C...STRONG SUNSHINE SHOULD STILL BOOST HIGHS IN THE MID 70S
FOR MOST AREAS.

FOR TONIGHT HIGH PRESSURE ALONG THE GULF COAST SHOULD MOVE EAST TO
COASTAL GEORGIA. SINCE WE`RE NORTH OF THE RIDGE THIS MEANS THE
GRADIENT WILL SUPPORT A GENERALLY WESTERLY WIND. IN THE UPPER LEVELS
CHANNELED VORTICITY SHOULD REMAIN NORTH OF THE CAROLINAS WITH
INSUFFICIENT MOISTURE EXPECTED FOR CLOUDS. THIS MEANS RADIATIONAL
COOLING SHOULD PROCEED UNINHIBITED...AND LOWS SHOULD FALL INTO THE
48-52 RANGE...EXCEPT SOME MID TO UPPER 50S AT THE BEACHES.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...LARGE CLOSED LOW SPINNING ACROSS SE CANADA
WILL DRIVE NEARLY FLAT/ZONAL FLOW ACROSS THE CAROLINAS THROUGH
MID- WEEK. THIS WILL CREATE FAIRLY SEASONABLE AND QUIET
WEATHER...BUT A WEAK COLD FRONT IS PROGGED TO DROP ACROSS THE AREA
VERY EARLY THURSDAY. HIGH PRESSURE WILL BE OFFSHORE WEDNESDAY WITH
RETURN FLOW AHEAD OF THE COLD FRONT DRIVING TEMPS TOWARDS 80
BENEATH A LOT OF SUNSHINE. CLOUD COVER WILL GRADUALLY INCREASE WED
NIGHT INTO THURSDAY AS THE COLD FRONT APPROACHES FROM THE
NW...DRIVEN BY A PIECE OF VORT ENERGY ROTATING AROUND THE LARGE
CANADIAN VORTEX. GUIDANCE STILL SUGGESTING ONLY A SMALL CHANCE FOR
SHOWERS WITH THIS FEATURE AS FORCING IS WEAK AND THE COLUMN
REMAINS DRY. WILL KEEP INHERITED SCHC POP FOR THURSDAY...BUT NOT
EXPECTING WIDESPREAD OR SIGNIFICANT RAINFALL THURSDAY.
HOWEVER...CLOUDS AND ANY SHOWERS WILL KEEP TEMPS THURSDAY A BIT
COOLER THAN WED...WITH WIDESPREAD MID 70S EXPECTED. DRYING WILL
OCCUR THURSDAY NIGHT...ALLOWING TEMPS TO FALL WELL INTO THE
50S...A SOLID 5+ DEGREES COOLER THAN WED NIGHT LOWS.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
AS OF 300 AM TUESDAY...BIGGEST CONCERN FOR THE EXTENDED IS A
SIGNIFICANT LOW PRESSURE SYSTEM PROGGED TO MOVE ACROSS THE
SOUTHEAST AND TAP GULF MOISTURE DURING SATURDAY. STILL LOTS OF
UNCERTAINTY DUE TO LACK OF MODEL AGREEMENT...AND WHILE THE GFS HAS
BEEN CONSISTENT BRINGING MOISTURE IN FRIDAY NIGHT WITH SOAKING
RAINS ON SATURDAY...THE ECMWF IS SLOWER AND MORE SUPPRESSED WITH
THE BAROCLINIC GRADIENT LEADING TO LESS QPF AND A BETTER FRI
NIGHT/SATURDAY. IT IS GETTING LATE IN THE YEAR FOR SUCH AN
EQUATORWARD PUSH OF THE BAROCLINIC GRADIENT...SO THE ECMWF MAY BE
TOO SUPPRESSED...BUT WILL MAKE VERY LITTLE CHANGE TO INHERITED AND
MAINTAIN A SPLIT OF THE GUIDANCE WHICH AGREES WITH CURRENT WPC
FORECASTS. THEREAFTER...COOLER WEATHER WILL PREVAIL AS DRYING
OCCURS SUNDAY...AND THESE BELOW NORMAL TEMPS WILL PERSIST THROUGH
THE END OF THE PERIOD EVEN BENEATH FULL LATE-APRIL INSOLATION.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
AS OF 06Z...AREA OF HIGH CLOUDS IS EXITING THE COASTAL AREAS WITH
DRIER AIR NOTED IN WATER VAPOR STREAMING INTO THE REGION FROM THE
WEST AND SOUTHWEST. AS A RESULT...HIGH CONFIDENCE THAT VFR
CONDITIONS WILL PREVAIL TONIGHT THROUGH TUESDAY NIGHT.
OTHERWISE... WINDS WILL VEER WITH THE APPROACH OF THE FRONT
THROUGH THE EARLY MORNING HOURS TUESDAY.

EXTENDED OUTLOOK...EXPECT VFR WITH POSSIBLE SHOWERS THURSDAY AND
SATURDAY.

&&

.MARINE...
NEAR TERM /THROUGH TONIGHT/...
AS OF 300 AM TUESDAY...THE COLD FRONT WILL PUSH ACROSS INTERSTATE 95
SHORTLY...REACHING THE BEACHES AROUND SUNRISE. THIS WILL FINALLY END
THE BREEZY SOUTHWEST WINDS WE HAVE EXPERIENCED OVERNIGHT...REPLACING
IT WITH GENTLER WEST WINDS THIS MORNING. WITH LOTS OF SUNSHINE AN
AFTERNOON SEABREEZE SHOULD DEVELOP...BACKING NEARSHORE WINDS AROUND
TO THE SOUTHWEST.

HIGH PRESSURE OVER THE GULF COAST WILL MOVE SLOWLY EAST TO COASTAL
GEORGIA BY DAYBREAK WEDNESDAY. THIS WILL MAINTAIN THE WESTERLY WIND
TONIGHT. SEAS CURRENTLY 4-5 FEET ACROSS THE NC WATERS AND 3-5 FEET
ACROSS THE SC WATERS WILL DIMINISH TO 2-3 FEET THIS AFTERNOON AND
TONIGHT.

SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
AS OF 300 AM TUESDAY...HIGH PRESSURE OFFSHORE WILL MAINTAIN SW
RETURN FLOW WEDNESDAY...BUT SPEEDS INCREASE THROUGH THE DAY THANKS
TO A PINCHING GRADIENT AHEAD OF A COLD FRONT. WIND SPEEDS WILL
RISE TO 15-20 KTS WED NIGHT BEFORE SHIFTING TO THE NW EARLY
THURSDAY BEHIND THE FRONT. THESE NW WINDS WILL PERSIST AND BE
LIGHT MOST OF THURSDAY...BUT VEER MORE TO THE NORTH AND INCREASE
LATE TO 10-15 KTS. WAVE HEIGHTS WILL BE HIGHEST IMMEDIATELY AHEAD
OF THE FRONTAL PASSAGE...RISING TO 3-4 FT WITH A SW WIND CHOP AND
SE GROUND SWELL COMPRISING THE SPECTRUM. N/NW WINDS THURSDAY WILL
PUSH HIGHEST SEAS AWAY FROM SHORE...LEAVING 1-3 FT WAVES IN THE
COASTAL WATERS.

LONG TERM /FRIDAY THROUGH SATURDAY/...
AS OF 300 AM TUESDAY...A COLD FRONT WILL WAVER BACK AND FORTH
ACROSS THE WATERS FRIDAY...LEAVING HIGHLY VARIABLE WIND
DIRECTIONS...FROM NORTH EARLY...TO SW LATE...AND THEN TO N/NE
SATURDAY MORNING. FORTUNATELY THE DIFFUSE GRADIENT ALLOWING THIS
TO OCCUR WILL KEEP SPEEDS AROUND 10 KTS EXCEPT VERY EARLY FRIDAY
WHEN THEY MAY REACH 15 KTS. THESE N/NE WINDS WILL PERSIST SATURDAY
AHEAD OF A LOW PRESSURE SYSTEM APPROACHING FROM THE SW...BUT THE
GRADIENT REMAINS LAX SO SPEEDS WILL HOVER AROUND 10 KTS. WITH THE
LIGHT GRADIENT IN PLACE AND NO SIGNIFICANT SWELL...SEAS WILL BE
MOSTLY 2-3 FT THROUGH THE PERIOD...ALTHOUGH A BIT OF AN
AMPLIFICATION IS POSSIBLE LATE SATURDAY.

&&

.ILM WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
NC...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...JDW
NEAR TERM...TRA
SHORT TERM...JDW
LONG TERM...JDW
AVIATION...TRA
MARINE...TRA/JDW



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