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 191119 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 619 AM EST FRI DEC 19 2014 .SYNOPSIS... HIGH PRESSURE WILL RIDGE DOWN INTO THE AREA TODAY CREATING ONE LAST NICE DAY. THIS HIGH WILL WEDGE DOWN THE COAST DURING THE WEEKEND...WHILE LOW PRESSURE MOVES NEARBY SATURDAY BRINGING RAIN AND COOL TEMPERATURES. A SECOND LOW PRESSURE WILL BRING MORE CLOUDS AND RAIN ON MONDAY...ESPECIALLY NEAR THE COAST. A LARGE LOW PRESSURE REMAINING TO THE WEST WILL DRIVE A STRONG COLD FRONT THROUGH THE CAROLINAS ON WEDNESDAY. COLD AND DRY WEATHER IS EXPECTED FOR CHRISTMAS DAY. && .NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM FRIDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: SEASONAL TEMPERATURES IN STORE TODAY AND TONIGHT AS THE SOUTHEAST EXTENSION OF A HIGH CENTERED OVER THE GREAT LAKES REGION CONTINUES A COOL NORTH TO NORTHEAST FLOW OVER THE EASTERN CAROLINAS. MODEL CONSENSUS...WITH A BIAS TOWARDS THE BETTER-PERFORMING GFS MOS...GIVES US HIGHS IN THE MID TO UPPER 50S MOST PLACES AND OVERNIGHT LOWS IN THE MID TO UPPER 30S. MODEL SOUNDINGS AND SATELLITE LOOPS SHOW THAT MAINLY CIRRUS OF VARYING EXTENT AND THICKNESS ALONG WITH SOME MID-LEVEL CLOUDS WILL CONTINUE TO STREAM OVERHEAD EARLY THIS MORNING AND INTO THE DAYLIGHT HOURS. HOWEVER...EXTENSIVE BREAKS IN THIS COVER WILL LEAD TO AMPLE SUNSHINE INTO THE AFTERNOON HOURS. CLOUD COVER WILL LOWER AND THICKEN OVERNIGHT AS A SYSTEM EMERGING FROM THE GULF OF MEXICO APPROACHES FROM THE SW. CHANCES FOR LIGHT RAIN WILL INCREASE FROM THE SW AFTER MIDNIGHT AS THIS SYSTEM MOVES CLOSER...ALTHOUGH AT THIS STAGE ANY ACCUMULATIONS ARE EXPECTED TO BE NIL TO MINIMAL. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM FRIDAY...WET AND RAW SATURDAY STILL ON TAP AS A RATHER QUICK-HITTING LOW PRESSURE SYSTEM MOVES OVERHEAD. A PERIOD OF DEEP ISENTROPIC LIFT WILL STILL OCCUR OVER THE AREA THE FIRST HALF OF SATURDAY...BUT GUIDANCE CONTINUES TO BACK OFF ON STRENGTH AND DURATION OF THIS FORCING. THE ECMWF IS NOW REALLY THE ONLY GUIDANCE SHOWING A VERY HEAVY RAINFALL EVENT...AND THUS WILL LEAN ON THE DRIER HIGH RES SREF AS WELL AS THE GFS GUIDANCE. THIS SUGGESTS THE HIGHEST QPF WILL OCCUR OVER SOUTHERN PORTIONS OF THE CWA AS THE SYSTEM RACES EAST...AND DRYING BEGINS IN THE COLUMN AS EARLY AS SUNSET ON SATURDAY. WHILE TOTAL QPF WILL NOT BE VERY IMPRESSIVE...STILL FEEL CATEGORICAL POP IS WARRANTED...AND WITH THE WEDGE OF HIGH PRESSURE REMAINING IN PLACE WILL KEEP HIGHS ONLY IN THE UPPER 40S MOST PLACES AWAY FROM THE GRAND STRAND AND SOUTH SANTEE RIVER AREAS. LOWS SATURDAY NIGHT WILL BE A BIT ABOVE CLIMO NORMS...SLIGHTLY BELOW 40 INLAND...TO AROUND OR JUST ABOVE 40 AT THE COAST...AS CLOUDS LIMIT TOTAL COOLING. RESIDUAL LOW LEVEL MOISTURE REMAINS ON SUNDAY...BUT LACK OF FORCING SHOULD KEEP SUNDAY DRY...ALBEIT WITH PARTLY TO AT TIMES MOSTLY CLOUDY SKY CONDITIONS AND CONTINUED COOL TEMPS IN THE LOW 50S. THIS DRYING COULD BE SHORT LIVED HOWEVER...AS RESIDUAL BAROCLINIC INSTABILITY OFFSHORE IN CONJUNCTION WITH ANOTHER MID-LEVEL ENERGY IMPULSE MAY SPAWN ANOTHER LOW PRESSURE OFFSHORE SUNDAY NIGHT. AGAIN...ECMWF AND GFS DIFFER HIGHLY...BUT THE GFS HAS SUPPORT FROM THE CMC/SREF/NAM AND IS FAVORED. ADDITIONALLY...THE FASTER SOLUTION MAKES SENSE BASED OFF PROGRESSIVE FLOW AND CONTINUED PACIFIC JET ENERGY AS NOTED BY WPC. THUS...WHILE WILL NOT SHOW POP/QPF AS SIGNIFICANT AS INDICATED BY THE GFS/NAM...WILL BRING A RETURN OF QPF TO THE AREA SUNDAY NIGHT AND KEEP LOWS WELL ABOVE NORMAL A DEGREE OR TWO EITHER SIDE OF 40. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 330 AM FRIDAY...WELL AFTER MUCH OF DECEMBER WAS RATHER QUIET LOCALLY...PATTERN TAKES A DECIDEDLY MORE ACTIVE TURN DURING THE LAST FULL WEEK OF THE MONTH. MONDAY WILL BE WET AGAIN AS LOW PRESSURE DEVELOPS ALONG THE STALLED BAROCLINIC BOUNDARY OFFSHORE...AND SLINGS RAIN BACK INTO THE CAROLINAS. THE GFS REMAINS A STRONG OUTLIER IN TERMS OF QPF...BUT THE NAM/SREF/CMC HAVE BEEN TRENDING WETTER...AND MOIST ADVECTION IS PRETTY SIGNIFICANT...SO A BUMP TO LIKELY POP IS WARRANTED. CONTINUING TO FAVOR THE GFS IN THE EXTENDED...MONDAY NIGHT AND THE FIRST HALF OF TUESDAY LOOK TO FEATURE A BRIEF RESPITE FROM THE RAIN ALTHOUGH SHOWERS ARE STILL POSSIBLE IN AN ISOLATED NATURE. THEREAFTER...A POTENT STORM SYSTEM LOOKS MORE LIKELY TO DEVELOP AS THE MID-LEVEL FLOW BUCKLES IN RESPONSE TO STRONG RIDGING ACROSS THE WESTERN CONUS. AS A DEEP TROUGH DIGS ACROSS THE EAST...STRONG CYCLOGENESIS WILL OCCUR AND MOVE FROM THE GULF COAST UP INTO THE OH VLY. THERE IS GOOD AGREEMENT THAT THE SURFACE LOW WILL REMAIN WELL WEST OF THE LOCAL CWA...BUT DEEP MOIST ADVECTION WILL FUNNEL TREMENDOUS MOISTURE INTO THE CAROLINAS AND PERIODS OF HEAVY RAINFALL OR EVEN TSTMS WILL BE POSSIBLE AS THE COLD FRONT SWINGS ACROSS THE AREA ON WEDNESDAY. THE CURRENT SETUP COULD SUPPORT SOME STRONGER STORMS TUE/WED...BUT ITS STILL A BIT FAR OUT TO REALLY DETERMINE THIS POTENTIAL...WHICH IS MADE EVEN TOUGHER BY THE MODEL DISAGREEMENT. STILL...IT IS SOMETHING THAT BEARS WATCHING EARLY NEXT WEEK...ESPECIALLY WITH WEDNESDAY BEING A BIG TRAVEL DAY. STRONG CAA AND WILL FOLLOW BEHIND THE STORM SO CHRISTMAS LOOKS DRY...BUT COLD AND WINDY. && .AVIATION /11Z FRIDAY THROUGH TUESDAY/... AS OF 06Z...VFR CONDITIONS WILL PREVAIL AT ALL TERMINALS THROUGH THE VALID PERIOD. OVERNIGHT...WINDS WILL REMAIN CALM WITH CONTINUED SCT MID LEVEL CLOUDS INTO THE MORNING HOURS. STILL DO NOT ANTICIPATE ANY FOG ISSUES GIVEN THE UNFAVORABLE MOISTURE PROFILES AND INCREASING CLOUDINESS TOWARD DAYBREAK. TODAY...MORE CIRRUS WILL STREAM OVER THE CAROLINAS WELL AHEAD OF AN UPPER DISTURBANCE. WINDS WILL BECOME N-NE LESS THAN 10 KT DURING THE DAY. MID LEVEL CLOUDS WILL CONTINUE TO INCREASE THROUGH THE AFTERNOON HOURS...WITH VFR CIGS 10-15KFT DEVELOPING FROM WEST TO EAST AFTER 00Z SAT. EXTENDED OUTLOOK...RAIN LIKELY SAT WITH DEVELOPING MVFR/IFR CIGS POSSIBLY LASTING INTO SUN. CHANCE OF SHOWERS MON AS LOW PRESSURE MOVES UP THE COAST. SHOWERS POSSIBLE LATE TUE AHEAD OF A STRONG COLD FRONT. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 630 AM FRIDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: HIGH PRESSURE CENTERED OVER THE GREAT LAKES WILL MAINTAIN A LIGHT NORTH TO NORTHEASTERLY FLOW OVER THE WATERS THROUGH THE NEAR TERM. WINDS WILL STAY IN THE 10 KT RANGE TODAY...INCREASING TO 10 TO 15 KTS OVER OUR SC WATERS OVERNIGHT AS A FRONTAL SYSTEM APPROACHES FROM THE SW. SEAS WILL STAY IN THE 2 FT RANGE THROUGH THE PERIOD. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM FRIDAY...HIGH PRESSURE WEDGE WILL BE ENTRENCHED ALONG THE COAST DURING THE WKND...WHILE AN AREA OF LOW PRESSURE MOVES NEAR THE WATERS ON SATURDAY...WITH A SECOND LOW DEVELOPING OFFSHORE LATE SUNDAY. THIS LEAVES A PINCHED GRADIENT BETWEEN THE FEATURES...AND NE WINDS WILL BE PERSISTENT AT 10-15 KTS...AT TIMES HIGHER...THROUGH THE PERIOD. THESE PERSISTENT NE WINDS WILL DRIVE SEAS TO 2-4 FT MUCH OF THE WKND...WITH THE EXCEPTION BEING IN THE WAVE SHADOWED REGION SW OF BRUNSWICK COUNTY...WHERE 1-2 FT SEAS WILL BE MORE COMMON. LONG TERM /MONDAY THROUGH TUESDAY/... AS OF 330 AM FRIDAY...NE WINDS TO START THE PERIOD AT 10-15 KTS WILL BE HIGHLY VARIABLE ON MONDAY AS A LOW PRESSURE MOVES UP THE COAST. EXPECT WINDS TO VEER THROUGH NEARLY THE ENTIRE COMPASS ON MONDAY...SETTLING ON NW AT 5-10 KTS MONDAY NIGHT. A BRIEF PERIOD OF LIGHT WESTERLY WINDS WILL OCCUR TUESDAY MORNING...BUT A LARGE AND POTENT STORM SYSTEM WILL MOVE WELL WEST OF THE AREA BEGINNING TUESDAY NIGHT. THIS WILL CAUSE A TIGHT PRESSURE GRADIENT AND SW WINDS WILL RISE RAPIDLY LATE TUESDAY TO 15-20 KTS. SEAS MONDAY WILL BE 2-4 FT WITH SEVERAL DIFFERENT WAVE GROUPS IN THE SPECTRUM. WAVE HEIGHTS FALL TO AROUND 2 FT THE FIRST HALF OF TUESDAY...BEFORE RISING DRAMATICALLY LATE...AND HEADLINES MAY BE NEEDED BY THE END OF THE PERIOD. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...REK SHORT TERM...JDW LONG TERM...JDW AVIATION...REK/BJR MARINE...REK/JDW

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