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
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS62 KILM 221723 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1222 PM EST SAT NOV 22 2014 .SYNOPSIS... CLOUDS WILL SLOWLY INCREASE TODAY WITH TEMPERATURES REMAINING COOL. A DEVELOPING STORM SYSTEM BREWING IN THE GULF OF MEXICO WILL LIFT NORTHEAST BRINGING MUCH MILDER TEMPERATURES SUNDAY AND MONDAY...ALONG WITH UNSETTLED AND WET WEATHER. ANOTHER SYSTEM WILL BRING ANOTHER ROUND OF RAIN BY MIDWEEK WITH CONDITIONS DRYING OUT BY THE END OF THE WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM SATURDAY...DESPITE FULL SUNSHINE TODAY EXPECT ANOTHER DAY OF TEMPERATURES SOLIDLY BELOW CLIMO THANKS TO NE SURFACE FLOW BENEATH LOW LEVEL WARM AIR ADVECTION. SOME OF THE SC OFFSHORE MAY AFFECT COASTAL AREAS BUT VIS SAT IMAGERY SHOWING THIS NOW LESS LIKELY AS THE CLOUDS ARE HAVING TROUBLE NEGOTIATING THE NEARSHORE COOLER WATERS AND THEY ARE TENDING TO FAVOR THE WARMER GULF STREAM. NO CHANGES TO THE FORECAST AT THIS TIME. CLOUD COVER WILL TEND TO INCREASE TONIGHT BUT PROBABLY FAIRLY SLOWLY FOR THE FIRST HALF OF THE NIGHT FOLLOWED BY A RAPID INCREASE IN CLOUD COVER TOWARDS DAYBREAK. && .SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM SATURDAY...POTENT STORM SYSTEM...NOW SEEN ON IR SATELLITE IMAGERY MOVING ACROSS TEXAS WILL BRING A SIGNIFICANT RAIN EVENT TO THE AREA SUNDAY. THIS SYSTEM WILL MOVE UP INTO THE MISSISSIPPI VALLEY AND SHEAR OUT BUT COPIOUS MOISTURE NOW SEEN POOLING IN THE GULF OF MEXICO WILL BE DRAWN NORTHWARD IN A ORGANIZED FASHION. A LITANY OF FORCING MECHANISMS WILL BE WORKING IN TANDEM INCLUDING A DIFFUSE WARM FRONT AND SPEED CONVERGENCE FOR THE LOWER LEVELS AND MID AND UPPER LEVEL DIFLUENCE. LONG STORY SHORT...I HAVE ELEVATED POPS TO 100 ACROSS THE BOARD FOR LATE SUNDAY MORNING THROUGH THE EVENING HOURS. THE NAM IS A LITTLE FASTER MOVING THE SYSTEM THROUGH BUT OPTED FOR THE GFS SOLUTION CITING THE CONSISTENCY. SEVERE THREAT PARAMETERS REMAIN UNCHANGED...A LOT OF SHEAR AND LOW LEVEL HELICITY BUT THE INSTABILITY REMAINS IN QUESTION. SPC HAS NOW MOVED ALL AREAS OF THE CWA INTO A SLIGHT RISK WITH THE DAY TWO OUTLOOK. TEMPERATURE FORECAST REMAINS IN PLACE MOST NOTABLY THE EXPECTATION OF UPPER 70S MONDAY COURTESY OF THE STRONG SOUTHWEST FLOW THAT REMAINS IN PLAY...THIS DESPITE OVERCAST SKIES WITH LOWER CEILINGS. && .LONG TERM /MONDAY THROUGH FRIDAY/... AS OF 330 AM SATURDAY...MEDIUM RANGE GUIDANCE IS NOW COMING INTO BETTER AGREEMENT AT LEAST FOR THE FIRST COUPLE DAYS OF THE EXTENDED. A SECONDARY DEEP AND PROGRESSIVE SHORTWAVE DIVING INTO THE LOWER MISSISSIPPI VALLEY ONCE ACTS ON ABUNDANT MOISTURE FROM THE GULF OF MEXICO PAINTING ANOTHER WET SCENARIO FOR LATE TUESDAY AND WEDNESDAY. THE GUIDANCE HAS BEEN OFF AND ON THE PAST FEW DAYS WITH THIS SCENARIO BUT WITH BOTH THE GFS AND 0000 UTC ECMWF DEVELOPING RAIN WELL INLAND...CONFIDENCE IS HIGHER. THE PRIMARY FORCING WILL BE THE RIGHT ENTRANCE REGION OF THE 200-300 JET MOVING SLOWLY SOUTH TO NORTH ALONG THE COAST. I HAVE INCREASED POPS TO LIKELY FOR WEDNESDAY BUT SUBSEQUENT SHIFTS MAY WANT TO INCREASE TO CATEGORICAL IN SHORT ORDER. BEYOND THIS...A LITTLE BETTER AGREEMENT AS WELL WITH A BROAD TROUGH ENVELOPING THE EASTERN THIRD OF THE U.S WITH HIGH PRESSURE AT THE SURFACE. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... AS OF 18Z...HIGH PRESSURE WILL REMAIN IN CONTROL THROUGH THE OVERNIGHT HOURS...HOWEVER THINGS WILL DETERIORATE AFTER THAT. THE HIGH WILL SLOWLY SHIFT OFFSHORE TODAY...ALLOWING MOIST RETURN FLOW TO BEGIN LATE TONIGHT. LIGHT NORTHEAST FLOW TODAY...BECOMING EAST LATE THIS AFTERNOON AS THE HIGH SHIFTS OFFSHORE. LIGHT WINDS TONIGHT WITH INCREASING HIGH AND POSSIBLY MID CLOUDS AFTER MIDNIGHT IN ADVANCE OF THE NEXT SYSTEM. SUNDAY...STRONG ISENTROPIC LIFT WILL COMMENCE AROUND MID TO LATE MORNING...WITH MODERATE RAIN AND POSSIBLE IFR CONDITIONS POSSIBLE BY THE END OF THE FORECAST PERIOD. THE NEW MODEL RUN OF THE NAM IS STAYING FAIRLY CONSISTENT WITH THE PREVIOUS RUN. EXTENDED OUTLOOK...UNSETTLE WEATHER IS EXPECTED SUNDAY AFTERNOON THROUGH POSSIBLY TUESDAY...WITH OCCASIONAL SHOWERS AND MVFR/IFR CONDITIONS. VFR TUESDAY AFTERNOON WITH POSSIBLE MVFR CONDITIONS WEDNESDAY. VFR THURSDAY. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 930 AM SATURDAY...A GRADUAL VEERING TODAY FROM NE TO E WITH LITTLE CHANGE IN THE RELATIVELY LIGHT WIND SPEEDS EXPECTED. FORECAST APPEARS TO BE ON TRACK AND NO ADJUSTMENTS ARE EXPECTED AT THIS TIME. SMALL CRAFT ADVISORY ALSO CONTINUES AS THE WEATHER GOES RAPIDLY DOWNHILL HEADING INTO THE NEXT PERIOD. AS OF 345 AM SATURDAY...ELONGATED CENTER OF 1030+ MB HIGH PRESSURE PROGGED TO PUSH EAST ACROSS THE LOCAL WATERS TODAY...AND OFFSHORE TONIGHT. WITH SUCH A COMPACT HIGH... THE SFC PG QUICKLY TIGHTENS ACROSS THE LOCAL WATERS AS THE CENTER PULLS AWAY. LOOKING AT NE- ENE WINDS AT 10 TO 15 KT TODAY...WITH A MORE SOLID 15 KT ACROSS THE ILM SC WATERS. FOR TONIGHT...BEING ON THE BACKSIDE OF THE OFFSHORE MOVING HIGH...WINDS WILL SLIGHTLY VEER TO THE ENE TO ESE WITH AN INCREASE IN SPEEDS DURING THE PRE-DAWN SUN HOURS. STRATIFORM TYPE PCPN WILL BEGIN OVERSPREADING THE LOCAL ILM SC WATERS TOWARD DAYBREAK SUN. SIGNIFICANT SEAS WILL RANGE BETWEEN 2 AND 4 FT THRU TONIGHT...AND BEGIN TO FURTHER BUILD BY DAYBREAK SUN IN RESPONSE TO INCREASING ONSHORE TYPE WINDS. AVERAGE PERIODS WILL RANGE BETWEEN 4.5 TO 5.0 SECONDS. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 330 AM SATURDAY...BASED ON MODEL CONSISTENCY...WILL RAISE A SMALL CRAFT ADVISORY FOR ALL WATERS BEGINNING SUNDAY MORNING AND CONTINUING THROUGH TUESDAY AM. THIS AS A POTENT STORM SYSTEM AFFECTS THE SOUTHEAST. WINDS WILL QUICKLY RAMP UP FROM THE SOUTHEAST TO 20-25 KNOTS AND EVEN A LITTLE HIGHER SUNDAY AFTERNOON FOR A BRIEF PERIOD. WARM AIR ADVECTION AND LIMITED CONVECTIVE MIXING PROBABLY KEEPS A GALE WARNING OUT OF PLAY AS THE WINDS OFF THE DECK ARE QUITE STRONG. THIS WILL QUICKLY BUILD SEAS TO 5-8 FEET. THE WINDS WILL DIMINISH SLIGHTLY FOR MONDAY AND VEER TO THE SOUTHWEST BUT REMAIN SUFFICIENTLY STRONG...AROUND 20 KNOTS TO KEEP SEAS WORKED UP. A WEAKER WESTERLY FLOW SHOULD FINALLY GIVE MARINERS A BRIEF BREAK BEGINNING TUESDAY. LONG TERM /TUESDAY THROUGH WEDNESDAY/... AS OF 330 AM SATURDAY...RELATIVELY LIGHT WIND FIELDS TUESDAY AS WEAK HIGH PRESSURE BUILDS IN BRIEFLY. BY WEDNESDAY AN ELONGATED LOW DEVELOPS AND MOVES WELL OFFSHORE BUT IS ENOUGH TO GIVE MORE CONSISTENCY TO THE WIND DIRECTION...NORTH...NORTHEAST. SPEEDS WILL INCREASE TO 20-25 KNOTS AS WELL. SEAS WILL DIP TO A RANGE OF 2-4 FEET TUESDAY AND BUILD ONCE AGAIN WITH THE INCREASE IN WINDS WEDNESDAY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...SMALL CRAFT ADVISORY FROM 10 AM SUNDAY TO 7 AM EST TUESDAY FOR AMZ250-252-254-256. && $$ SYNOPSIS...SHK NEAR TERM...MBB/DCH SHORT TERM...SHK LONG TERM...SHK AVIATION...HDL

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