Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 131952 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 351 PM EDT SUN APR 13 2014 .SYNOPSIS...
-- Changed Discussion --
HIGH PRESSURE WILL CONTROL THE WEATHER PATTERN INTO MONDAY. A COLD FRONT WILL MOVE ACROSS THE AREA TUESDAY...WITH INCREASING CHANCES FOR SHOWERS AND POSSIBLY THUNDERSTORMS LATE MONDAY INTO TUESDAY. HIGH PRESSURE WILL MOVE INTO THE AREA WEDNESDAY AND CONTROL AREA WEATHER INTO FRIDAY BEFORE CONDITIONS DETERIORATE IN ADVANCE OF A COLD FRONT THAT WILL MOVE THROUGH THE AREA SATURDAY NIGHT OR EARLY SUNDAY.
-- End Changed Discussion --
&& .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 300 PM SUNDAY...HIGH PRESSURE CENTERED WELL OFFSHORE AND A BUILDING MID-LEVEL RIDGE HAS CREATED ANOTHER BEAUTIFUL MID-SPRING DAY ACROSS THE CAROLINAS. SOME INCREASED MOISTURE HAS HELPED SPAWN WIDESPREAD SCT/BKN DIURNAL CU ALONG AND AHEAD OF THE WESTWARD ADVANCING SEA BREEZE BOUNDARY. HRRR STILL SUGGESTS A FEW SHOWERS WILL DEVELOP WITHIN THIS CU TODAY BEFORE LOSS OF HEATING...BUT A SIGNIFICANT SUBSIDENCE INVERSION ABOVE 800MB IS PREVENTING MUCH VERTICAL DEPTH TO THE CU...AND THE MID-LEVELS REMAIN EXCEEDINGLY DRY. THUS...HAVE KEPT POP TO SILENT AND JUST CARRIED A TOKEN 5% ALONG THE SEA BREEZE UNTIL NIGHTFALL. ANY PRECIP CHANCES...ALONG WITH CONVECTIVE CLOUD COVER...WILL ERODE AFTER DARK WITH LOSS OF HEATING. WINDS WILL REMAIN ELEVATED TONIGHT WHICH ACT TO PUMP ADDITIONAL MOISTURE INTO THE LOW LEVELS OF THE ATMOSPHERIC COLUMN. ONCE AGAIN THERE MAY BE A FOG CONCERN TONIGHT. HOWEVER...THESE SAME WINDS WILL KEEP TEMPS ELEVATED...CREATING SURFACE DEWPOINT DEPRESSIONS SEVERAL DEGREES ABOVE 0. ADDITIONALLY...LLJ IS PROGGED TO RISE TO 25-30 KTS...ABOUT 10 KTS HIGHER THAN LAST NIGHT...WHICH WOULD LIKELY HELP MIX OUT MUCH IN THE WAY OF FOG. NEAR-SURFACE HYDROLAPSE RATES ARE ALSO MUCH LESS FAVORABLE. THEREFORE...HAVE KEPT ANY MENTION OF FOG OUT OF THE WX GRIDS...BUT SHALLOW FOG WILL BE POSSIBLE...ESPECIALLY INLAND. LOWS TONIGHT WILL STAY QUITE WARM ON THE SOUTHERLY WINDS...WITH LOWS DROPPING ONLY INTO THE LOW 60S ACROSS THE EASTERN HALF OF THE CWA...UPPER 50S IN THE FAR WESTERN ZONES.
-- End Changed Discussion --
&& .SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
-- Changed Discussion --
AS OF 300 PM SUNDAY...HIGH PRESSURE WILL SHIFT OFF THE COAST MONDAY AS A COLD FRONT APPROACHES FROM THE WEST AND PASSES THROUGH THE AREA LATE TUESDAY. THE RESULT WILL BE INCREASING CLOUDS ON MONDAY WITH THE POSSIBILITY OF ISOLATED TO SCATTERED AFTERNOON SHOWERS AND POSSIBLY THUNDERSTORMS. MAX TEMPERATURES WILL REACH THE MID 70S TO AROUND 80. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ARE POSSIBLE IN LOW LEVEL CONFLUENT FLOW MONDAY NIGHT AS THE FRONT CONTINUES TO APPROACH FROM THE WEST. LOWS WILL FALL TO THE LOW TO MIDDLE 60S UNDER A MAINLY CLOUDY SKY. NUMEROUS SHOWERS AND THUNDERSTORMS ARE ON TAP FOR TUESDAY INTO THE EARLY EVENING AS THE FRONT MOVES THROUGH THE AREA. WHILE WINDS AT H8 AND H9 ARE NOT OVERLY IMPRESSIVE...PEAKING AROUND 50 KT AT H8 AROUND 18Z...STORM RELATIVE HELICITY VALUES PEAK IN THE 250 TO 350 RANGE. GIVEN FORECAST MAX TEMPERATURES IN THE MIDDLE TO PERHAPS UPPER 70S...CAPE VALUES AROUND 1000 J/KG ARE ON TAP. THESE FACTORS COMBINED MAKE SEVERE THUNDERSTORMS A POSSIBILITY TUESDAY. A POTENTIAL FURTHER COMPLICATION FOR TUESDAY IS TEMPERATURES. TEXT MOS BULLETINS ARE GIVING MAX TEMPERATURES IN THE LOW TO MIDDLE 80S. UNLESS THERE ARE SIGNIFICANT BREAKS IN THE CLOUD COVER TUESDAY...THIS IS NOT EXPECTED TO HAPPEN BUT IF IT DID...THE RESULTING CAPE VALUES WOULD REACH OR EXCEED 2500 J/KG. THAT WOULD GREATLY ENHANCE SEVERE WEATHER POTENTIAL TUESDAY. THE FRONT IS EXPECTED TO MOVE OFF THE COAST EARLY TUESDAY EVENING AND BRING A RAPID END TO THE WIDESPREAD SHOWERS AND STORMS. STRONG CAA SETS UP LATE AND MINS WILL FALL INTO THE LOW TO MID 40S MOST AREAS EXCEPT FOR A FEW UPPER 40S SOUTH AND EAST.
-- End Changed Discussion --
&& .LONG TERM /WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
AS OF 300 PM SUNDAY...TWO OPPORTUNITIES FOR RAINFALL IN THE UPCOMING WEEK. ONE JUST PRIOR TO THE START OF THIS FORECAST PERIOD AND ANOTHER WITH A DEVELOPING COASTAL TROUGH LATE IN THE WEEK AND AHEAD OF A COLD FRONT. THE PASSAGE OF A COLD FRONT SAT NIGHT SHOULD END THE RISK FOR SHOWERS AND THUNDERSTORMS. IN THE WAKE OF A STRONG COLD FRONT...CHILLY HIGH PRESSURE WILL BUILD ACROSS THE AREA AND STRENGTHEN ACROSS NEW ENGLAND...EVOLVING INTO A PERSISTENT WEDGE WED AND THU. NE TO E FLOW IN THE LOWEST 5-6 KFT WILL BE TOPPED BY A WSW TO W FLOW. HOWEVER...PRECIPITABLE WATER VALUES WILL BE AS LOW AS A QUARTER OF AN INCH AND THE DRY AIR IN THE MID AND UPPER LEVELS OF THE ATMOSPHERE LOOK FORMIDABLE. THEREFORE... WILL REFRAIN FROM ANY MENTION OF PRECIPITATION IN THE MIDDLE OF THE WEEK. HOWEVER...PATTERN IS CONDUCIVE FOR THE DEVELOPMENT OF LOWER CLOUDS...ESPECIALLY AS THE LOW-LEVEL FLOW TURNS EASTERLY WED NIGHT AND THU. AS THE WEDGE REORIENTS ITSELF THU NIGHT AND FRI...WE WILL HAVE TO WATCH FOR THE DEVELOPMENT OF A COASTAL TROUGH. THE LONG TERM MODELS HAVE BEEN CONSISTENT WITH THE DEVELOPMENT OF THIS FEATURE...BUT DO DIFFER AS TO ITS JUXTAPOSITION. AS A COLD FRONT APPROACHES...THE WEDGE SHOULD BEGIN TO ERODE FRI AND FRI NIGHT AND THE COASTAL TROUGH SHOULD BE DRAWN TO A POSITION VERY NEAR...IF NOT ON THE COAST. THUS WILL TREND POPS HIGHER DURING THIS TIME. MIXED LAYER CAPE VALUES DO INCREASE FRI INTO SAT AHEAD OF THE FRONT AND WILL INCLUDE MENTION OF THUNDERSTORMS. IN THE WAKE OF COLD FRONTAL PASSAGE SAT NIGHT...DRIER AND MORE STABLE AIR MAY BE SLOW TO ARRIVE FOR SUN WITH PERHAPS AN UPPER LEVEL FEATURE TRAVERSING THE AREA AS MAIN UPPER LOW MOVES ACROSS THE GREAT LAKES AND NORTHEAST. COLUMN LOOKS MUCH TOO DRY BELOW 10 KFT TO SUPPORT RAINFALL AND SO WILL KEEP POPS BELOW THRESHOLD FOR THE LAST DAY OF THE UPCOMING WEEKEND. TEMPERATURES WILL BE COOL FOR MUCH OF THE LONG TERM FORECAST. TEMPERATURES WILL BE MUCH BELOW NORMAL WED AND THU AND MAXIMUMS MAY NOT EXCEED 60 DEGREES IN SOME AREAS. LOWS WED NIGHT AND THU NIGHT WILL BE WELL DOWN IN THE 40S AND MAY DROP INTO THE UPPER 30S IN SOME INLAND SPOTS. TEMPS WILL RECOVER SLOWLY FRI AND INTO THE WEEKEND AND SHOULD BE NEAR NORMAL FOR THE UPCOMING WEEKEND.
-- End Changed Discussion --
&& .AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
AS OF 18Z...COMBINATION OF THE MEAN WIND AND THE SEA BREEZE WILL CONTINUE TO CREATE S/SE WINDS THROUGH THE AFTN...STRONGEST AT THE COASTAL TERMINALS. DIURNAL CU ALONG AND AHEAD OF THE SEA BREEZE BOUNDARY WILL BECOME BKN...ESPECIALLY INLAND...BUT VFR WILL REMAIN THROUGH NIGHTFALL. THE HIGH-RES HRRR CONTINUES TO DEVELOP A FEW SHOWERS ACROSS THE AREA THIS AFTN...BUT BELIEVE THE AIR ALOFT IS TOO DRY TO SUPPORT ANYTHING MORE THAN AN ISOLATED SPRINKLE...SO HAVE NOT ADDED A MENTION INTO ANY TAF. WINDS WILL REMAIN ELEVATED TONIGHT WHICH SHOULD PREVENT MUCH IN THE WAY OF FOG LOCALLY...BUT SOME RESTRICTIONS ARE POSSIBLE...ESPECIALLY INLAND WHERE SURFACE DEWPOINT DEPRESSIONS WILL BE LESS THAN NEAR THE COAST AND WINDS WILL BE LIGHTER. HAVE ADDED A TEMPO MVFR GROUP AT FLO/LBT...ALONG WITH SOME SCT IFR STRATUS SINCE WINDS OF 25-30 KTS ABOVE THE NOCTURNAL INVERSION COULD FORCE A STRATUS LAYER AS OPPOSED TO FOG. SOME STRATUS MAY ALSO ADVECT ONSHORE NEAR THE MYRTLES TOWARDS MORNING. VFR WILL RETURN ON MONDAY. EXTENDED OUTLOOK...CHANCE OF SHOWERS AND MVFR CONDITIONS LATE MONDAY THROUGH TUESDAY WITH SHOWERS AND/OR THUNDERSTORMS ALONG A PASSING COLD FRONT. VFR WEDNESDAY AND THURSDAY. POSSIBLE FOG/STRATUS THURSDAY NIGHT INTO FRIDAY.
-- End Changed Discussion --
&& .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/... AS OF 300 PM SUNDAY...HIGH PRESSURE EXTENDING BACK ACROSS THE COASTAL WATERS FROM WELL OFFSHORE WILL MAINTAIN ITS INFLUENCE LOCALLY THROUGH TONIGHT. A VERY WEAK PRESSURE GRADIENT HAS KEPT WINDS BELOW 10 KTS TODAY...BUT THESE WILL RISE SLOWLY TONIGHT TO 10-15 KTS FROM THE S/SE AROUND THE HIGH PRESSURE. THIS COMBINATION OF INCREASED WINDS AND A CONTINUING LOW-AMPLITUDE SE GROUND SWELL WILL DRIVE SEAS UP TO 2-4 FT BY THE END OF THE PERIOD. SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/... AS OF 300 PM SUNDAY...INCREASING WINDS AND SEAS ARE EXPECTED THROUGH THE PERIOD AS A COLD FRONT APPROACHES FROM THE WEST MONDAY AND MONDAY NIGHT BEFORE MOVING THROUGH THE AREA TUESDAY. S TO SE WINDS OF 10 TO 15 KT MONDAY WILL INCREASE TO 15 TO 20 KT MONDAY NIGHT. SPEEDS WILL RAMP UP TO 20 TO 25 KT TUESDAY BEFORE RAPIDLY SHIFTING TO THE NORTH AND INCREASING TO 25 TO 30 KT LATE TUESDAY NIGHT. SEAS OF 3 TO 4 FT MONDAY MORNING WILL BUILD TO 4 TO 6 FT BY TUESDAY MORNING AND PEAK AROUND 7 FT DURING THE DAY TUESDAY. AFTER THE FROPA TUESDAY EVENING...SEAS WILL FURTHER BUILD TUESDAY NIGHT...PERHAPS REACHING 8 OR 9 FT AT 20 NM BY DAYBREAK TUESDAY. DUE TO UNCERTAINTIES IN THE EXACT TIMING...WILL NOT ISSUE A 4TH PERIOD SMALL CRAFT ADVISORY BUT ONE WILL BE REQUIRED AT SOME POINT TUESDAY AND A GALE WARNING MAY BE REQUIRED FOR TUESDAY NIGHT. LONG TERM /WEDNESDAY THROUGH FRIDAY/... AS OF 300 PM SUNDAY...A PROLONGED PERIOD OF SMALL CRAFT ADVISORY CONDITIONS IS EXPECTED. GUSTS TO GALE FORCE ARE POSSIBLE INTO WED. THE TIGHTEST PRESSURE GRADIENT IS EXPECTED TO DEVELOP IN THE WAKE OF A STRONG COLD FRONT AS STRONG HIGH PRESSURE NOSES INTO THE CAROLINAS AND THEN EVOLVES INTO A PERSISTENT WEDGE OF HIGH PRESSURE WED AND THU. THE STRONGEST WINDS ARE EXPECTED INTO WED AND IT IS DURING THIS TIME THAT GUSTS TO GALE FORCE ARE MOST PROBABLE. SUSTAINED WIND SPEEDS MAY BRIEFLY REACH GALE CRITERIA DURING THIS TIME. ONCE THE VERY TIGHT PRESSURE GRADIENT DEVELOPS...IT IS EXPECTED TO PERSIST. THEREFORE...WIND SPEEDS ARE EXPECTED TO REMAIN ABOVE SMALL CRAFT ADVISORY THRESHOLDS INTO THU NIGHT OR FRI. THE WIND DIRECTION WILL BE NE...VEERING TO A MORE EASTERLY DIRECTION AS A COASTAL TROUGH BECOMES MORE PRONOUNCED ON FRI. SEAS WILL BE HIGHEST WED...7 TO 9 FT AND UP TO 10 FT NEAR FRYING PAN SHOALS BUOY AS A DRY AND CHILLY NE SURGE ENVELOPS THE WATERS. SEAS WILL LIKELY NOT FALL BELOW 6 FT ACROSS THE OUTER WATERS UNTIL FRI.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ NEAR TERM...JDW SHORT TERM...31 LONG TERM...RJD AVIATION...43/JDW

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