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 011125 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 725 AM EDT FRI AUG 1 2014 .SYNOPSIS... A COASTAL FRONT JUST OFFSHORE WILL PUSH INLAND TODAY...THEN WILL STALL OVER THE AREA FROM THIS AFTERNOON THROUGH THE WEEKEND. THIS WILL BRING GOOD RAIN CHANCES...WITH PERIODS OF HEAVY RAINFALL POSSIBLE TODAY THROUGH MONDAY. MORE SEASONABLE WEATHER WILL DEVELOP THE MIDDLE OF NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 730 AM FRIDAY...FIRST ROUND OF SHOWERS AND THUNDERSTORMS IS PASSING TO THE NORTH AS THE NEXT WAVE APPROACHES THE COAST FROM THE SOUTH. HAVE UPDATED FORECAST TO TRY TO CAPTURE TIMING OF PRECIP...OTHERWISE FORECAST REASONING REMAINS UNCHANGED. PREVIOUS DISCUSSION FOLLOWS: A COASTAL FRONT OFFSHORE IS WORKING ITS WAY BACK TO THE COAST AS AN UNSEASONABLY DEEP LONG WAVE TROUGH MAINTAINS ITS POSITION OVER EASTERN CONUS. GUIDANCE IN GOOD AGREEMENT THAT THE FRONT WILL PUSH ASHORE THIS MORNING AND THEN STALL SOMEWHERE OVER THE FORECAST AREA THIS AFTERNOON AND OVERNIGHT. GUIDANCE ALSO IN GOOD AGREEMENT THAT A DEEP LAYER TROPICAL MOISTURE PLUME WILL CONTINUE TO ADVECT OVER THE EASTERN CAROLINAS THROUGH THE NEAR TERM...WITH P/W VALUES IN THE 2 INCH RANGE THROUGHOUT. IN ADDITION...AT LEAST ONE UPPER SHORT WAVE DISTURBANCE WILL ROTATE THROUGH THE BASE OF THE LONG WAVE TROUGH AND THEN OVER THE FORECAST AREA TODAY. EXTENSIVE CLOUDINESS WILL LIMIT INSTABILITY AND THUS LIMIT ANY POTENTIAL SEVERE THUNDERSTORM COVERAGE. HOWEVER...SHEAR PROFILES TODAY BECOME A BIT MORE FAVORABLE FOR THE VERY SLIGHT CHANCE OF TORNADIC ACTIVITY. IN FACT...WE HAVE ALREADY SEEN MULTIPLE...MAINLY WEAK...INDICATIONS OF LOW LEVEL ROTATION ON THE RADAR AND HAVE ISSUED ONE WARNING FOR A POTENTIAL TORNADO BASED SOLELY ON RADAR RETURNS. NO TORNADO HAS BEEN CONFIRMED AS OF THIS WRITING...BUT WOULD NOT BE SURPRISED TO SEE REPORTS OF A WEAK TORNADO AT THE END OF THE DAY. STAGE IS THEREFORE SET FOR A CLOUDY AND UNSETTLED DAY. POPS WILL BE LIKELY TO CATEGORICAL TODAY AND TONIGHT. A POSSIBLY GREATER THREAT THAN TORNADOS IS THE CHANCE OF LOCALIZED FLOODING FROM HEAVY RAIN IN TRAINING STORMS. EXTENSIVE CLOUD COVER AND PRECIPITATION WILL KEEP DAYTIME TEMPERATURES BELOW NORMAL...WITH HIGHS IN THE MID 80S MOST PLACES. MODEL CONSENSUS HAS OVERNIGHT LOWS OF AROUND 70. && .SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM FRIDAY...THE WEEKEND CONTINUES TO LOOK QUITE WET AND COOL...EVEN AS THE PERSISTENT DEEP UPPER TROUGH BEGINS TO WEAKEN ACROSS THE EAST. ALTHOUGH THE TROUGH WILL BEGIN TO FILL...RELATIVELY LOWERED THICKNESSES WILL PERSIST AS A SHORTWAVE MOVES ACROSS THE OH VLY AND INTO THE MID-ATLANTIC. THIS WILL HAVE THE EFFECT OF KEEPING THE TROUGH AS THE DRIVING INFLUENCE ALOFT...WITH CONTINUED MOIST ADVECTION ON S/SW MID-LEVEL WINDS. AT THE SURFACE...COASTAL TROUGH WHICH MOVES INLAND BEFORE THE PERIOD...WILL STALL ACROSS...OR JUST INLAND...OF THE CWA...PUMPING MOIST SE WINDS INTO THE AREA AND SERVING AS A CONVERGENT FOCUS FOR SHOWERS AND STORMS. ALL THIS COMBINES WITH PERSISTENT UPPER DIFFLUENCE WITHIN THE ENTRANCE REGION TO A JET STREAK ACROSS THE NORTHEAST...AND THE WKND LOOKS TO BE PRETTY MUCH A WASH OUT. MOS NUMBERS ARE ALREADY CATEGORICAL...BUT WITH NO SINGLE TIME PERIOD FAVORED...WILL CONTINUE WITH HIGH-LIKELY FOR THE WKND. QPF COULD BE QUITE SUBSTANTIAL AS WELL...WITH 1-3" OF RAIN EXPECTED...ALONG WITH ISOLATED HIGHER TOTALS. THE CLOUDS...RAIN...AND LOWERED THICKNESSES WILL KEEP HIGHS BELOW NORMAL FOR EARLY-AUGUST...BUT AT THE SAME TIME MAINTAIN NORMAL OR SLIGHTLY ABOVE NORMAL LOWS. EXPECT HIGHS IN THE LOW 80S BOTH DAYS...AND LOWS IN THE LOW 70S. && .LONG TERM /MONDAY THROUGH THURSDAY/... AS OF 230 PM THURSDAY...ATYPICALLY WELL DEFINED (FOR THE TIME OF YEAR) MID AND UPPER LEVEL TROUGHINESS TO OUR WEST ON SUNDAY. DECAYING SURFACE BOUNDARY TO PROVIDE LOW LEVEL LIFT...WHICH WILL THEN BE AIDED BY MID LEVEL PVA AND UPPER DIVERGENCE ASSOC WITH RIGHT ENTRANCE OF UPPER JET STREAK ACROSS NORTHEAST AND MID ATLANTIC. AND WHILE RAIN CHANCES SEEM TO WARRANT LIKELY POPS MODELS ARE NOT SUGGESTIVE OF HIGH QPF AMOUNTS. THIS MAY BE DUE TO IT BEING SUCH A CLOUDY DAY THAT VERY LITTLE INSTABILITY MANAGES TO DEVELOP SAVE FOR PERHAPS ALONG THE IMMEDIATE COAST. THESE PLAYERS ALL REMAIN NEARLY IN PLACE HEADING INTO MONDAY ALTHOUGH ALL OF THEM WEAKEN. LOOKING FOR ANOTHER DAY OF HIGH POPS AND SUPPRESSED AFTERNOON TEMPS. TUESDAY SHOULD BRING LOWER RAIN CHANCES BUT STILL ONES THAT ARE HIGHER THAN NORMAL. THE UPPER JET CONTINUES TO WEAKEN AND LIFT OUT TO THE NORTHEAST WHILE THE MID LEVEL TROUGH WEAKENS...BUT ALSO SENDS ITS REMAINING VORT CENTER ACROSS THE CAROLINAS. IN RESPONSE TO THIS THE GFS STRAIGHTENS THE PIEDMONT TROUGH AT THE SURFACE. WE ALSO MAY SEE A BIT MORE SUNSHINE IN CONTRAST TO THE EARLY PARTS OF THE PERIOD. TUESDAY MAY THUS BE A DAY WHERE WE TRANSITION TO MORE SCATTERED AND DEEPER CONVECTION ESP IF TEMPS START BOUNCING BACK TOWARDS CLIMO. WEDNESDAY AND THURSDAY LOOK SEASONABLE WITH RESPECT TO BOTH TEMPERATURES AND AREAL COVERAGE OF CONVECTION. MID LEVEL FLOW SHOULD BE OF A DRIER WESTERLY DIRECTION WHILE SOME SEMBLANCE OF A PIEDMONT TROUGH REMAINS. && .AVIATION /12Z FRIDAY THROUGH TUESDAY/... AS OF 12Z...LOOKS LIKE MOST OF THE CONVECTION WILL WAVE NORTH OF ILM BY 13Z...AND MAY AFFECT LBT FOR THE FIRST COUPLE OF HOURS THIS MORNING. THERE MAY BE A BIT OF A LULL IN THE ACTION AS THIS FIRST IMPULSE MOVES NORTH OF THE REGION. WITH PWATS AROUND 2 INCHES AND A LOW LFC...JUST A BIT OF HEATING WILL LIKELY POP THIS AGAIN AROUND MIDDAY...CONTINUING THROUGH THE AFTERNOON HOURS. CONVECTION WILL SLOWLY WEAKEN THROUGH THE EVENING HOURS...HOWEVER WEAK IMPULSES TONIGHT COULD PRODUCE CONVECTION AT ALMOST ANY TIME. SOUTHEAST FLOW THROUGH THE PERIOD. EXTENDED OUTLOOK...SHRA/TSRA LIKELY WITH PERIODS OF MVFR CONDITIONS THROUGH MON AS A FRONT STALLS AND FINALLY DISSIPATES OVER THE EASTERN CAROLINAS. A CHANCE OF SHOWERS CONTINUES ON TUE. && .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 7:30 AM FRIDAY...NO CHANGES TO THE FORECAST WITH THE LATEST UPDATE. PREVIOUS DISCUSSION FOLLOWS: A WARM FRONT OVER THE WATERS WILL PUSH WEST AND ASHORE THIS MORNING. WINDS WILL VEER FROM PRESENT EASTERLY DIRECTION TO SE LATER TODAY AND THEN SOUTH OVERNIGHT. WINDS WILL STAY IN THE GENERAL 10 TO 15 KT RANGE...WITH SEAS RANGING FROM 3 TO 4 FT THROUGH THE PERIOD. SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/... AS OF 330 AM FRIDAY...COASTAL TROUGH WILL STALL INLAND OF THE WATERS DURING THE WEEKEND...WHILE HIGH PRESSURE RIDGE EXPANDS ACROSS THE ATLANTIC TO THE EAST. THIS LEAVES THE COASTAL WATERS PINCHED BETWEEN THE TWO...AND ALTHOUGH THE GRADIENT WILL REMAIN RELATIVELY WEAK...WINDS WILL BE 10-15 KTS BOTH DAYS...WITH A S/SE DIRECTION PREDOMINANT. SEAS WILL BE 2-4 FT THROUGH THE WEEKEND...WITH A SE GROUND SWELL AMPLIFYING...COMBINING WITH A SOUTHERLY WIND WAVE TO FORM THE ENTIRE WAVE SPECTRUM. LONG TERM /SUNDAY THROUGH TUESDAY/... AS OF 230 PM THURSDAY...LIGHT SOUTHERLY WINDS ON SUNDAY WITH FRONTAL BOUNDARY JUST INLAND OF THE COAST. WIND CHOP WILL BE COINCIDENT WITH 11 SECOND SOUTHEASTERLY SWELL. THE WEAKENING BOUNDARY WILL MOVE FURTHER INLAND FOR THE REMAINDER OF THE PERIOD AND THE WEST ATLANTIC HIGH POKES A BIT WESTWARD FURTHER INTO THE CAROLINAS. THIS COULD LEAD TO AN OCCASIONAL INCREASE IN FLOW BY A FEW KNOTS AND ALSO A SLIGHT VEER FROM S TO SW. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...REK/III NEAR TERM...REK SHORT TERM...JDW LONG TERM...MBB AVIATION...DL MARINE...REK/JDW/MBB

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