264  
FXUS62 KILM 281759  
AFDILM  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE WILMINGTON NC  
ISSUED BY NATIONAL WEATHER SERVICE CHARLESTON SC  
159 PM EDT FRI APR 28 2017  
   
SYNOPSIS
 
 
EXPECT HIGH PRESSURE TO EXTEND ACROSS THE AREA FROM OFFSHORE  
THROUGH SUNDAY. EXPECT WARM TEMPERATURES AND ISOLATED SEA BREEZE  
CONVECTION, MAINLY ON SUNDAY. THE NEXT COLD FRONT WILL BRING A  
CHANCE OF SHOWERS AND THUNDERSTORMS LATE MONDAY INTO EARLY  
TUESDAY. HIGH PRESSURE WILL FOLLOW FOR THE MID-WEEK PERIOD. LOW  
PRESSURE SYSTEM MAY IMPACT THE REGION DURING THURSDAY WITH A  
SOAKING RAIN.  
 

 
   
NEAR TERM /THROUGH TONIGHT/
 
 
NO MAJOR CHANGES FOR THE EARLY AFTERNOON UPDATE. ISOLATED  
AFTERNOON CONVECTION DUE TO THE SEABREEZE CANNOT BE ENTIRELY  
RULED OUT SO WILL BLEND INTO THE PREVIOUS POPS FORECAST. MINOR  
NEAR-TERM ADJUSTMENTS TO HOURLY SURFACE PARAMETERS HAVE BEEN  
MADE BASED ON OBSERVATIONS, BUT PREVIOUS FORECAST APPEARS  
LARGELY ON TRACK. THE BERMUDA HIGH STRETCHING INTO THE FORECAST  
AREA WILL PROMOTE HUMID CONDITIONS WITH ABOVE AVERAGE  
TEMPERATURES, ESPECIALLY INLAND. EXPECT HIGH TEMPERATURES IN THE  
MID TO UPPER 80S AWAY FROM THE COAST.  
 

 
   
SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/
 
 
HIGH PRESSURE AND RIDGING ALOFT AND AT THE SFC WILL BE THE  
PRIMARY DRIVERS AFFECTING SENSIBLE WEATHER ACROSS THE ILM CWA.  
CLOSED HIGH WITH HEIGHTS OF 590+ DAM WILL ANCHOR OFFSHORE AND  
EAST OF THE CAROLINAS DURING THIS PERIOD. THE CENTER OF THE SFC  
HIGH WILL BASICALLY PARK UNDERNEATH THE UPPER HIGH OFFSHORE WITH  
RIDGING EXTENDING WESTWARD AND ONSHORE IN THE VICINITY OF CAPE  
ROMAIN ON SAT, AND ONSHORE AND INLAND IN THE VICINITY OF CAPE  
FEAR SUNDAY. A SEMI-TIGHTENED SFC PG WILL OCCUR ACROSS THE FA  
THRUOUT THIS PERIOD KEEPING S TO SW WINDS ACTIVE, EVEN DURING  
THE EVENING AND OVERNIGHT. THE SEA BREEZE EACH AFTN AND EVENING  
WILL FURTHER ENHANCE THE S WINDS. AN ACTIVE LOW LEVEL JET WILL  
KEEP WINDS BUSY DURING THE OVERNIGHT, PREVENTING ANY WIDESPREAD  
FOG DEVELOPMENT, BUT ENOUGH MOISTURE IN THE LOW LEVELS MAY  
RESULT IN LOW STRATUS OR STRATUS FRACTUS EACH EARLY MORNING.  
 
THE SUBSIDENCE FROM THE RIDGING WILL KEEP POPS IN CHECK ON  
SATURDAY BUT COULD SEE ISOLATED SEA BREEZE INDUCED CONVECTION  
DURING SUNDAY WITH THE SUBSIDENCE WEAKENING SLIGHTLY. DAILY HIGH  
TEMPERATURES FOR SATURDAY WILL RUN IN THE 80S TO LOWER 90S  
INLAND, AND FOR SUNDAY MAINLY WIDESPREAD 80S DUE TO WINDS HAVING  
BECOME MORE SOUTHERLY THRUOUT ENABLING SOME MARINE INFLUENCE TO  
EXTEND WELL INLAND. BALMY NIGHTS CAN BE EXPECTED WITH UPPER 60S  
TO LOWER 70S.  
 

 
   
LONG TERM /SUNDAY THROUGH THURSDAY/
 
 
SURFACE AND MID LEVEL RIDGE WILL WEAKEN AND DRIFT EAST MON,  
ALLOWING A COLD FRONT TO APPROACH FROM THE W. LOW PRESSURE AND  
ASSOCIATED STRONG DYNAMICS AND UPPER LEVEL SUPPORT WILL BE WELL  
DISLOCATED FROM THE CAROLINAS AS A COLD FRONT MOVES ACROSS THE  
AREA MON NIGHT. THIS SUGGESTS CONVECTION WEAKENING AS IT MOVES  
INTO THE EASTERN CAROLINAS. CURRENT TIMING BRINGS THE LIKELIHOOD  
FOR SHOWERS AND THUNDERSTORMS LATER MON AND MON NIGHT.  
 
AS THE FRONT MOVES OFF THE COAST TUE MORNING, HIGH PRESSURE  
ALONG THE GULF COAST WILL SLIDE EAST AND THEN OFFSHORE TO OUR S  
DURING WED. THIS SHOULD BRING A DRY PERIOD. DEEP LOW PRESSURE  
WILL MOVE OUT OF THE MID SOUTH AND GULF COAST STATES WED,  
LIFTING SLOWLY TO THE NE. ITS ASSOCIATED COLD FRONT WILL MOVE  
INTO THE SOUTHEAST STATES THU-THU NIGHT, BRINGING THE RISK FOR  
ROBUST THUNDERSTORMS.  
 

 
   
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
 
 
DIURNAL CUMULUS FIELD WILL PERSIST ACROSS THE REGION THIS  
AFTERNOON WITH ONLY SLIGHT CHANCES FOR PRECIPITATION.  
PROBABILITIES OF DIRECT IMPACTS AT ANY OF THE TERMINALS DUE TO  
SHOWERS/TSTORMS ARE TOO LOW TO MENTION IN THE 18Z TAF CYCLE.  
SOUTHERLY WINDS WILL REMAIN GUSTY NEAR THE COAST THROUGH THE  
EVENING HOURS DUE TO SEABREEZE ENHANCEMENT. MODEL GUIDANCE  
SUGGESTS THAT RESTRICTIONS OVERNIGHT DUE TO LOWERING CEILINGS  
AND/OR VSBYS ARE PROBABLE, WITH THE MOST LIKELY OUTCOME BEING  
LOW CEILINGS DUE TO A NOCTURNAL JET SUSTAINING MIXING NEAR THE  
SURFACE. THIS WILL AID IN PREVENTING WIDESPREAD SURFACE-BASED  
FOG AND WILL MAINTAIN ELEVATED SURFACE WINDS THROUGH MOST OF THE  
NIGHT.  
 
EXTENDED OUTLOOK...VFR THROUGH SUNDAY WITH BRIEF MVFR CONDITION  
POSSIBLE ACROSS THE COASTAL TERMINALS DUE TO SPOTTY SEA BREEZE  
CONVECTION. PERIODS OF IFR/MVFR CONDITIONS POSSIBLE IN  
SHOWERS AND THUNDERSTORMS LATE MONDAY INTO EARLY TUESDAY.  
 

 
   
MARINE
 
 
NEAR TERM /THROUGH TONIGHT/...  
AS OF 330 AM FRIDAY...SOUTHWESTERLY FLOW WILL BE KING WITH A  
LARGE AREA OF HIGH PRESSURE ACROSS MUCH OF THE WESTERN ATLANTIC  
CENTERED WELL EAST OF BERMUDA. WITH SUCH A BROAD SWATH OF FLOW  
COMING ACROSS THE BAHAMAS AND INTO THE SOUTHEAST A SWELL  
COMPONENT WILL BE ABLE TO COEXIST WITH THE RELATIVE SMALL WIND  
WAVES. FOR THE MOST PART THIS WILL YIELD A FORECAST OF 2 TO 4 FT  
FOR ALL ZONES.  
 
SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...  
AS OF 330 AM FRIDAY...SFC HIGH PRESSURE PARKED OFFSHORE FROM THE  
CAROLINAS WILL EXTEND WESTWARD AND ONSHORE IN THE VICINITY OF  
CAPE ROMAIN SATURDAY, AND ONSHORE VICINITY OF CAPE FEAR SUNDAY.  
WINDS SATURDAY WILL RUN S TO SW AT 10-15 KT, WITH THE SW  
DIRECTION MAINLY OCCURRING OVER THE WATERS FROM CAPE FEAR  
NORTHWARD. FOR SUNDAY, THE SLIGHT DEVIATION WITH THE SFC RIDGING  
WILL PRODUCE SOUTH WINDS THRUOUT WITH SPEEDS 10 TO 15 KT  
INITIALLY, INCREASING TO 15 TO 20 KT AS THE SFC PG FURTHER  
TIGHTENS AS AN EASTWARD MOVING COLD FRONT TRACKS INTO THE  
WESTERN CAROLINAS LATE SUNDAY NIGHT. THE SEA BREEZE EACH DAY  
WILL RESULT IN WINDS GUSTING AROUND 20 KT NEAR SHORE.  
SIGNIFICANT SEAS WILL RUN 2 TO 4 FT, CHOPPY NEARSHORE EACH AFTN  
AND EARLY EVENING DUE TO THE SEA BREEZE INFLUENCE. SEAS WILL  
BUILD SUNDAY NIGHT REACHING 3 TO 5 FT BY DAYBREAK MON. A  
SE TO SSE PSEUDO SWELL AT 5 TO 7 SECOND PERIODS WILL BE THE  
PRIMARY DRIVER FOR SIGNIFICANT SEAS THIS PERIOD.  
 
LONG TERM /MONDAY THROUGH TUESDAY/...  
AS OF 300 PM THURSDAY...WESTERN ATLANTIC HIGH PRESSURE WILL  
BRING INCREASING S WINDS AHEAD OF A COLD FRONT. SOUTH WINDS 15  
TO 20 KT EARLY MON WILL INCREASE LATE MON AND MON NIGHT, UP TO  
20 TO 25 KT WITH SEAS 3 TO 5 FT AT THE START BUILDING TO 5 TO 8  
FT. IN THE WAKE OF THE COLD FRONTAL PASSAGE EARLY TUE, OFFSHORE  
WINDS WILL SLOWLY DIMINISH. THE OFFSHORE TRAJECTORIES WILL KNOCK  
SEAS DOWN AND WE SHOULD DROP BELOW SMALL CRAFT ADVISORY LEVELS  
BY TUE EVE.  
 

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

 
 

 
SYNOPSIS...  
NEAR TERM...  
SHORT TERM...  
LONG TERM...  
AVIATION...  
MARINE...  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab NC Page
The Nexlab SC Page Main Text Page