Area Forecast Discussion
Issued by NWS Wilmington, NC

Current Version | Previous Version | Text Only | 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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 061051 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 651 AM EDT WED MAY 6 2015 .SYNOPSIS... A LOW PRESSURE SYSTEM ORGANIZING NEAR THE BAHAMAS WILL LIFT NORTH TODAY AND THEN MEANDER AND STRENGTHEN OFF THE SOUTHEAST COAST INTO THE WEEKEND. THIS SYSTEM MAY TRACK VERY CLOSE TO THE COAST...CREATING PERIODS OF GUSTY WINDS AND HEAVY RAINFALL THURSDAY THROUGH SATURDAY. THIS LOW PRESSURE WILL WEAKEN BUT MAY CONTINUE TO CREATE UNSETTLED WEATHER THROUGH MONDAY. && .NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
AS OF 645 AM WEDNESDAY...THE FA WILL SEE NO PCPN OCCURRENCE TODAY...ATLEAST THROUGH MIDNIGHT TONIGHT. SYNOPTICALLY...THIS IS IN RESPONSE TO AN UPPER RIDGE ACROSS THE FA THAT CONTINUES TO PROVIDE SUBSIDENCE ALOFT. AT THE SFC...RIDGING WILL CONTINUE TO EXTEND WESTWARD INTO THE CAROLINAS FROM THE HIGHS CENTER WELL OFFSHORE FROM CAPE HATTERAS...THRU THIS EVENING. TODAYS AMOUNT OF INSOLATION REACHING THE GROUND WILL SOMEWHAT BE LIMITED DUE TO THE OPAQUE CI/CS DECK OVERHEAD. THEREFORE...WILL ACTUALLY LOWER TODAYS HIGHS BY A DEGREE OR 2 FROM TUESDAYS RECORDED MAXES. THE STEADY ONSHORE FLOW WILL CONTINUE FOR THE 3RD STRAIGHT DAY...AND THIS TOO HAS LIMITED MAX TEMPS ACROSS THE COASTAL AREAS AS WELL AS INLAND LOCATIONS DUE TO THE ADJACENT SSTS STILL IN THE 60S. ONE HAS TO VENTURE OUT TO THE GULF STREAM TO OBSERVE THOSE 70+ DEGREE SSTS. DURING THE PRE-DAWN THU HOURS...HAVE INDICATED SLIGHT OR LOW CHANCE POPS AT BEST FOR MAINLY THE IMMEDIATE COASTAL COUNTIES. MUCH OF THIS DEPENDS ON THE TRACK OF THE SFC LOW...WHICH AT THIS TIME MSAS FINALLY IDENTIFIED IT AS A CLOSED LOW OVER THE WATERS EAST OF MIAMI. THE VARIOUS MODELS LOOKING AT THIS SFC LOW...GFS/NAM/EUROPEAN/AND ETC...HAVE ATLEAST AGREED WITH ONE ANOTHER FOR ATLEAST THE NEAR TERM PERIOD WITH REGARD TO THE LOWS EFFECT ON THE ILM CWA THROUGH DAYBREAK THU. THIS ALSO INCLUDES THE ONSHORE NE-E WINDS INCREASING...ALONG WITH THE SURF AND ASSOCIATED WAVE ENERGY...WHICH WILL RESULT IN BEACHES LIKELY SEEING AN INCREASE IN RIP CURRENT THREAT LATER TODAY...ESPECIALLY SOUTH OF THE NC-SC BORDER. UNFORTUNATELY...THE VARIOUS MODELS JUST AFTER THE NEAR TERM PERIOD CONTINUE TO EXHIBIT SOME DIVERGENCE... ALTHOUGH NOT AS WILDLY DIFFERENT...WITH THEIR RESPECTIVE SOLUTIONS IN DEALING WITH THIS HYBRID SUBTROPICAL LOWS MOVEMENT/INTENSITY/LIFE HISTORY/ETC.
-- End Changed Discussion --
&& .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 AM WEDNESDAY...A TROUGH OF LOW PRESSURE CURRENTLY BLOSSOMING OFF THE SOUTH FLORIDA COAST IS EXPECTED TO INTENSIFY OFF THE SOUTHEAST COAST THROUGH LATE WEEK...AND POSSIBLY DEVELOP SOME TROPICAL OR SUBTROPICAL CHARACTERISTICS AS IT MEANDERS IN THE VICINITY. UNFORTUNATELY...EVEN AT THIS TIME RANGE THERE IS MUCH LOWERED CONFIDENCE THAN USUAL...BUT HOPEFULLY SOME OF THIS WILL BE IMPROVED TODAY AS NHC IS PLANNING ITS FIRST RECON FLIGHT INTO THE SYSTEM. THAT BEING SAID...I STILL NEED TO WRITE A DISCUSSION AND CREATE A FORECAST EVEN WITH LIMITED CONFIDENCE. THERE ARE A FEW THINGS WE CAN GLEAN FROM THE SETUP AND FROM THE GUIDANCE...EVEN THOUGH WHOLESALE CHANGES CANNOT BE MADE. THERE IS HIGH CONFIDENCE THAT A LOW PRESSURE WILL DEVELOP...AND THAT IT WILL MEANDER SLOWLY NEAR THE COAST AS IT GETS BLOCKED BY MID-LEVEL RIDGING TO THE NORTH. THERE IS HIGH CONFIDENCE THAT IT WILL RETROGRADE WEST OR EVEN SW THU/FRI...AND THERE IS HIGH CONFIDENCE THAT PERIODS OF RAINFALL...POSSIBLY HEAVY AT TIMES...WILL IMPACT AT LEAST THE COASTAL SECTIONS OF THE CWA. BEYOND THAT HOWEVER...TIMING...TRACK...INTENSITY...AND OTHER IMPACTS (WIND...CONVECTION...DURATION) ARE STILL VERY MUCH IN QUESTION. THE NAM IS LIKELY TOO STRONG AND TOO FAR NORTH...WHILE THE GFS LIES ON THE WEAK/SOUTH END OF THE ENVELOPE. AN INTERMEDIATE SOLUTION OF THE ECMWF/CMC MAY BE MOST PRUDENT AT THIS POINT THEN. WILL CONTINUE WITH THE INHERITED FORECAST AND SHOW HIGHEST POP ON FRIDAY...BUT OTHERWISE ATTM EXPECT DETERIORATING CONDITIONS THURSDAY INTO FRIDAY WITH AT LEAST INCREASING WINDS AND PERIODS OF SHOWERS...SOME OF WHICH AGAIN...MAY BE HEAVY AT TIMES. HIGH TEMPS WILL LIKELY REMAIN JUST BELOW CLIMO IN THE TROPICAL AIR MASS DUE TO RAIN AND CLOUDS...WITH HIGHS STAYING IN THE MID TO UPR 70S. MINS WILL STAY ABOVE CLIMO AS GUSTY WARM WINDS AND CLOUDS KEEP LOWS WELL INTO THE 60S. && .LONG TERM /SATURDAY THROUGH TUESDAY/... AS OF 300 AM WEDNESDAY...HOW THE LONG TERM DEVELOPS WILL HINGE STRONGLY ON WHAT OCCURS DURING THE SHORT TERM. A LOW PRESSURE SYSTEM...POSSIBLE SUBTROPICAL STORM...WILL STILL BE SOMEWHERE IN THE VICINITY...POSSIBLY INLAND...POSSIBLY STILL OFFSHORE...DEPENDING ON WHICH MODEL IS PREFERRED. FAVOR THE SLOWER GUIDANCE AT THIS POINT...BUT WITH SO MUCH UNCERTAINTY STILL IN THE FORECAST AS THE SYSTEM MEANDERS BENEATH AN UPPER RIDGE...WILL AGAIN MAKE ONLY MINIMAL CHANGES TO THE EXTENDED. UNSETTLED WEATHER ASSOCIATED WITH THIS LOW PRESSURE MAY PERSIST INTO MONDAY WITH PERIODS OF RAIN AND WIND...BEFORE AN UPPER TROUGH FINALLY KICKS THE SYSTEM OFF TO THE NORTHEAST AHEAD OF A COLD FRONT WHICH WILL APPROACH AT THE END OF THE PERIOD. TEMPS SAT-MON WILL HOVER AROUND CLIMO...DEPENDING ON HOW THE LOW EVOLVES...BUT SHOULD WARM QUITE A BIT AHEAD OF THE COLD FRONT EARLY NEXT WEEK. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... AS OF 06Z...HIGH PRESSURE CENTERED WELL OFFSHORE FROM CAPE HATTERAS WILL CONTINUE TO RIDGE BACK TO THE WEST ACROSS NC TODAY. GOOD DECK OF MAINLY OPAQUE CI/CS ACROSS ALL LOCATIONS WILL AFFECT THE FA THRUOUT THIS 06Z ISSUANCE PERIOD...AND LIKELY LIMIT MORNING MVFR CONDITIONS FROM BR. THE BEST THREAT FOR BR WILL BE ACROSS LBT/FLO TERMINALS. LATEST MSAS SHOWS A CLOSED SFC LOW JUST OFF MIAMI. LATEST MODELS INDICATE THIS SFC LOW TO FURTHER DEVELOP AND LIFT NORTHWARD LATER TODAY THROUGH TONIGHT. MODEL CONFIDENCE REMAINS LOW WITH ITS INTENSITY BUT SLIGHTLY BETTER IN ITS NORTHWARD MOVEMENT/POSITIONING. NEVERTHELESS...WILL INDICATE MID- HIGH LEVEL BKN/OVC CEILINGS BY LATE THIS AFTN THRU 06Z THU. AS FOR PCPN CHANCES...WILL GO WITH THE VCSH FOR THE MYR AND CRE COASTAL TERMINALS ONLY FOR SEVERAL HRS LEADING UP TO 06Z THU. EXTENDED OUTLOOK...LOW CONFIDENCE REMAINDER OF EXTENDED DUE TO UNCERTAINTY IN TRACK OF HYBRID LOW OFF THE SOUTHEAST U.S. COAST THU THRU THE UPCOMING WEEKEND. VFR TO MVFR BY THU...WITH MVFR/IFR FROM RAIN/CEILINGS AND INCREASING ONSHORE WINDS BY LATE THU...FRI INTO THE UPCOMING WEEKEND. BASICALLY LOOKING AT WORSE CONDITIONS ALONG THE IMMEDIATE COAST DURING THE EXTENDED. && .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/... AS OF 645 AM WEDNESDAY...SCA HAS BEEN RAISED FOR ALL WATERS...COMMENCING AT MIDNIGHT TONIGHT. THE SFC RIDGE AXIS EXTENDING WEST FROM THE HIGHS CENTER WELL EAST AND OFFSHORE FROM CAPE HATTERAS...WILL REMAIN NORTH OF THE AREA WATERS TODAY. THIS MEANS A CONTINUED ONSHORE FLOW FROM THE ENE-ESE TO START TODAY...WITH A RELAXED TO MODEST SFC PG RESULTING IN 10-15 KT TO START THIS MORNING. THE SFC LOW HAVING BEEN ADVERTISED TO DEVELOP ALL WEEK OFF FLORIDA OR ACROSS THE BAHAMAS...HAS FINALLY DEVELOPED INTO A CLOSED CIRCULATION OFF THE WATERS EAST OF MIAMI VIA MSAS ATTM. MODELS HAVE COME CLOSER TOGETHER WITH THEIR RESPECTIVE SOLUTIONS FOR ATLEAST THE NEAR TERM PERIOD IN THE FURTHER DEVELOPMENT AND MOVEMENT OF THIS HYBRID SUBTROPICAL/TROPICAL LOW TO THE NORTH BY NORTHEAST...REACHING THE OFFSHORE ATL WATERS OFF THE SOUTHEAST U.S. COAST LATER TONIGHT. AS A RESULT...WILL FURTHER INCREASE THE ONSHORE FLOW TONIGHT DUE TO THE TIGHTENING OF THE SFC PG THAT WILL PRODUCE 10 TO 20G25 KT WINDS...ALONG WITH A SLIGHT BACKING OF THE WIND DIRECTIONS TO THE NE-ENE BASED ON THE SFC PRESSURE PATTERN OF THIS LOW AS IT MOVES IN CLOSER PROXIMITY. SIGNIFICANT SEAS ARE ALREADY IN THE 2 TO 4 FT RANGE...AND WILL FURTHER BUILD TO 3 TO 5 FT THIS AFTN AND EVENING...AND LIKELY RANGE BETWEEN 3 TO 6 FT BY DAYBREAK THU. WILL BE LOOKING AT DOMINATING PERIODS IN THE 7 TO 9 SECOND PERIOD RANGE. THIS HIER RANGE ALREADY A RESULT OF 2 TO 3 DAYS WORTH OF ONSHORE FLOW OVER A DECENT FETCH LEADING UP TO THE COASTAL WATERS AND THE IMMEDIATE COAST. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 300 AM WEDNESDAY...SMALL CRAFT ADVISORY HAS BEEN HOISTED BEGINNING TONIGHT...AND WILL PERSIST THROUGH AT LEAST 8PM FRIDAY NIGHT AS A LOW PRESSURE DEVELOPS AND STRENGTHENS OFFSHORE. THERE IS STILL CONSIDERABLE UNCERTAINTY EVEN IN THE SHORT TERM...BUT IT APPEARS A LOW PRESSURE SYSTEM DEVELOPING OFF THE FLORIDA COAST WILL MOVE NORTH AND THEN STALL NEAR THE LOCAL WATERS THU/FRI. AS IT MEANDERS IN THE VICINITY IT WILL CAUSE INCREASING WINDS FROM THE E/NE...POSSIBLY BECOMING NORTH LATE ACROSS THE SOUTHERN WATERS...ALL AT SPEEDS OF 15-20 KTS. THESE COULD BECOME HIGHER (OR LOWER) DEPENDING ON HOW THE LOW PRESSURE EVOLVES. REGARDLESS...MARINE CONDITIONS WILL BECOME POOR AS THESE INCREASED WINDS AND AN AMPLIFYING SWELL PUSH SEAS UP TO 4-8 FT THROUGH MOST OF THE PERIOD. SOME IMPROVEMENT IS CURRENTLY FORECAST LATE...BUT THIS MAY CHANGE ONCE THE TRACK OF THE LOW BECOMES MORE CLEAR...AND MARINERS SHOULD KEEP APPRISED OF THIS EVOLVING SITUATION. LONG TERM /SATURDAY THROUGH SUNDAY/... AS OF 300 AM WEDNESDAY...LOW PRESSURE WILL LIKELY STILL BE IMPACTING THE AREA THROUGH THE WKND...BUT HOPEFULLY IN A WEAKENED STATE. UNCERTAINTY REMAINS THROUGH THE EXTENDED...AND WHILE CONDITIONS ARE NOT CURRENTLY FORECAST TO BE HEADLINE CRITERIA...THEY WILL REMAIN HAZARDOUS WITH A VARIETY OF WIND DIRECTIONS AND SPEEDS POSSIBLE AS THE LOW CENTER MOVES...POSSIBLY DIRECTLY ACROSS THE COASTAL WATERS. ATTM EXPECT THE NC WATERS TO EXPERIENCE WORSE CONDITIONS THAN OFF THE SC COAST...BUT AGAIN...MUCH STILL MAY CHANGE. WINDS OF 15-20 KTS FROM THE EAST ARE LIKELY NORTH OF THE LOW...WITH WEAKER N/NW WINDS ON THE BACK SIDE OF THE SYSTEM. WAVE HEIGHTS WILL REMAIN IN THE 3-5 FT RANGE AS A HIGH AMPLITUDE SWELL PERSISTS EVEN AS WINDS BEGIN TO EASE.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 8 PM EDT FRIDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...JDW AVIATION...DCH

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