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 262237 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 635 PM EDT WED AUG 26 2015 .SYNOPSIS... A FRONT WILL OSCILLATE ACROSS THE COAST INTO THURSDAY WHILE GRADUALLY LOSING IDENTITY. HIGH PRESSURE WILL SLOWLY BUILD INTO THE CAROLINAS THIS WEEKEND. ERIKA IS EXPECTED TO APPROACH THE BAHAMAS AND SOUTH FLORIDA LATE IN THE WEEKEND INTO EARLY NEXT WEEK. && .NEAR TERM /THROUGH TONIGHT/... AS OF 312 PM WEDNESDAY...CONVECTION HAS YET TO EVOLVE AS ROBUSTLY AS PREVIOUSLY ANTICIPATED...BUT THE ENVIRONMENT STILL APPEARS TO BE RIPE FOR TSTMS THIS AFTN THROUGH TONIGHT. STATIONARY FRONT ALIGNED VERY NEAR THE COAST IS SLOWLY BEING ABSORBED/COMBINED WITH THE SEA BREEZE WHICH IS JUST NOW BEGINNING TO DEVELOP. THIS LATE START TO HEATING IS DUE TO THE PRONOUNCED CLOUD COVER FROM THIS MORNING (POST FRONTAL STRATUS AND ANVIL DEBRIS) THAT ONLY RECENTLY ERODED. WHILE HEATING HAS BEEN SLOW...IT IS STILL VERY UNSTABLE OUTSIDE WITH SPC MESOANALYSIS SHOWING 2000-3000 J/KG OF SBCAPE ALONG THE EASTERN COUNTIES. THIS IS HIGHLY UNSTABLE...SO ANY UPDRAFTS FORCED BY SURFACE BASED CONVERGENCE ALONG THE SEA BREEZE...FRONT...OR DIFFERENTIAL HEATING BOUNDARIES...ARE STILL EXPECTED TO RISE QUICKLY INTO TSTMS. ADDITIONALLY...A SHORTWAVE EVIDENT ON WV IMAGERY LIFTING NE FROM THE GULF COAST WILL COMBINE WITH ENHANCING DIFFLUENCE AT 300 MB TO PROVIDE UPPER SUPPORT. IN OTHER WORDS...ALL SIGNS STILL POINT TO CONVECTION BLOSSOMING THIS EVENING...AND HIGH RES GUIDANCE...WHILE NOT AS AGGRESSIVE AS EARLIER STILL SHOWS SCATTERED TO WIDESPREAD CONVECTION DEVELOPING THROUGH THIS EVENING. HAVE TRIMMED POP BACK TO HIGH CHC FROM THE EARLIER LIKELY...BUT MANY PLACES STILL FACE THE RISK OF TORRENTIAL RAINFALL WITH ISOLATED FLOODING...SIGNIFICANT LIGHTNING...AND MAYBE AN ISOLATED DAMAGING WIND GUST. POP WILL WANE SLOWLY AFTER DARK WITH LOSS OF HEATING...BUT THE PRESENCE OF THE UPPER FEATURES WILL HAVE THE POTENTIAL TO MAINTAIN CONVECTION THROUGH THE OVERNIGHT HOURS...ALTHOUGH IN A WEAKER AND LESS WIDESPREAD FASHION. TEMPS TONIGHT WILL FALL SLOWLY AS CLOUDS AND SOUTHERLY WINDS EAST OF THE FRONT MAINTAIN A VERY WARM AND HUMID AIRMASS. A SIGNIFICANT TEMP GRADIENT IS FORECAST ACROSS THE CWA FOR MINS...DROPPING TO AROUND 69 WELL INLAND...BUT STAYING AS WARM AS 75 ALONG THE IMMEDIATE COAST. && .SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 312 PM WEDNESDAY...LOCAL ATMOSPHERIC CONDITIONS WILL REMAIN FAVORABLE FOR CONVECTION ALONG THE COAST AND COASTAL INTERIOR THURSDAY AND FRIDAY...AS A WAVERING BUT DECAYING FRONTAL BOUNDARY REMAINS QUASI-STATIONARY NEAR THE LAND-SEA INTERFACE. TROPICAL MOISTURE WILL REMAIN DEEPEST OFFSHORE BUT RICH ENOUGH TO SERVE AS FUEL IN LATE AUGUST HEATING ACROSS THE EASTERN ZONES. EXPECTATION OF SEA-BREEZE CONVERGENCE MAY VERY WELL CO-MINGLE WITH THE DETERIORATING FRONT TO ADD ADDITIONAL UPDRAFT FOCUS BY THE AFTERNOON BOTH DAYS. TIME HEIGHT DEPICTIONS OF RH IN THE COLUMN SUGGEST GRADUAL DRYING AND ANTICYCLONIC TURNING OF THE ATMOSPHERE AS AN UPPER RIDGE BUILDS FROM THE SE FRIDAY...AND COULD REDUCE POP POTENTIAL FRIDAY COMPARED TO THURSDAY. TEMPERATURES OF MAX/MIN WILL HOLD CLOSE TO NORMALS FOR LATE AUGUST BOTH DAYS...ALTHOUGH CLOUD COVER AND WEAK POST FRONTAL AIR MAY RESULT IN MIDDLE 80S MOST LOCATIONS. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... AS OF 312 PM WEDNESDAY...BY SATURDAY ERIKA...OR REMNANTS OF...MAY BE MOVING INTO THE FAR EASTERN BAHAMAS. CURRENT MODEL SPREADS BY DAY 5 MONDAY BECOME HIGHLY DIVERGENT...PLACING ERIKA ANYWHERE FROM THE EASTERN GULF OF MEXICO TO SEVERAL HUNDRED MILES EAST OF FLORIDA. IN LIGHT OF THE PRESENT UNCERTAINTY...COUPLED WITH A DECENT CONSENSUS THAT UPPER RIDGING WILL STRENGTHEN INTO THE CAROLINAS...THE EXTENDED FORECAST DOES NOT REFLECT ANY DIRECT IMPACTS FROM ERIKA. EXCEPTION POTENTIALLY COULD BE ARRIVAL OF SWELL WAVE ENERGY...PROVIDED ERIKA INTENSIFIES AS DEPICTED BY THE OFFICIAL NHC TRACKS...THOUGH EVEN THIS PARAMETER CARRIES LIMITED CONFIDENCE. AS A RESULT...FORECAST IN DAYS 4-7 REPRESENTS NEAR CLIMATOLOGICAL CONDITIONS FOR LATE AUGUST WITH MAXIMUMS IN THE UPPER 80S TO AROUND 90...MINIMUMS IN THE LOW 70S...DOTTED WITH ISOLATED TO SCATTERED SHOWERS AND TSTMS. A LOCAL ELEVATED RIP CURRENT THREAT COULD ARRIVE ON OUR BEACHES BY THIS WEEKEND. && .AVIATION /00Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
AS OF 00Z...CONVECTION IS WANING...ALTHOUGH THIS IS COUNTER TO WHAT THE NAM IS SHOWING WITH CONVECTION ONGOING THROUGH 06Z. THINK THIS SCENARIO IS TOO PESSIMISTIC AS THE CELLS WERE TRAINING AND WORKED THE ATMOSPHERE OVER PRETTY GOOD. DEBRIS CLOUDS WILL KEEP FOG ALONG THE COAST AT A MINIMUM...HOWEVER WITH ALL THAT WATER ON THE GROUND AT MYR WHERE THE FLOODING OCCURRED...IF THEY CLEAR OUT COULD SEE SOME IFR CONDITIONS. WILL REEVALUATE IN A FEW HOURS AND AMEND IF NECESSARY. SOME LIGHT FOG INLAND WITH MVFR STRATUS EXPECTED. WEDNESDAY...PREDOMINATELY VFR WITH NORTHEAST FLOW. A SLIGHT CHANCE OF CONVECTION AROUND MAX HEATING. EXTENDED OUTLOOK...PREDOMINATELY VFR WITH ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS THROUGH THE EXTENDED. BRIEF MORNING FOG/STRATUS IS ALSO EXPECTED EACH DAY.
-- End Changed Discussion --
&& .MARINE... NEAR TERM /THROUGH TONIGHT/... AS OF 312 PM WEDNESDAY...COLD FRONT/SEA BREEZE HYBRID IS SLOWLY LIFTING BACK TO THE NW...WITH A WEAK GRADIENT REMAINING IN PLACE ACROSS THE WATERS. WINDS HAVE BEEN VARIABLE ACROSS THE WATERS...BUT ARE TURNING TO A PREDOMINANT SOUTHERLY DIRECTION...STRONGEST WITHIN THE SEA BREEZE CIRCULATION WHERE SPEEDS MAY REACH UP TO 15 KTS...10 KTS ELSEWHERE. LATEST BUOY OBS CONTINUE TO SHOW AN 10-11 SEC PERIOD SE SWELL AS THE DOMINANT WAVE GROUP...AND THIS WILL PERSIST THROUGH TONIGHT WITH WAVE HEIGHTS REMAINING AROUND 2-3 FT. SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... AS OF 312 PM WEDNESDAY...MANAGEABLE MARINE CONDITIONS THURSDAY AND FRIDAY...WITH ONSHORE E-SE WINDS 10-15 KT BOTH DAYS OUTSIDE OF TSTMS. SEA SPECTRUM WILL CONSIST OF ESE WAVE 2-3 FEET EVERY 10 SECONDS ACCOMPANIED BY A LIGHT TO MODERATE ONSHORE DIRECTED CHOP. TSTMS WILL BE SCATTERED OVER THE 0-20 NM WATERS AND MARINERS SHOULD GET A RADAR UPDATE BEFORE HEADING OUT...AS SOME STORMS BECOME STRONG AND CAPABLE OF PRODUCING MORNING WATER SPOUTS. LONG TERM /SATURDAY THROUGH MONDAY/... AS OF 312 PM WEDNESDAY...SATURDAY THROUGH MONDAY THERE APPEARS AGREEMENT AMONG GFS/ECMWF PLOTS THAT DESPITE THE SPECIFIC ARRANGEMENT OR CONFIGURATION OF THE SYNOPTIC PATTERN...THE PRESSURE GRADIENT/PATTERN WILL BE A FLAT ONE. THIS SUGGEST LIGHT WINDS. SEAS HOWEVER DEPENDING ON HOW ERIKA INTENSITY TRENDS PAN-OUT...MAY BE LACED WITH AN UNDERLYING LONG PERIOD SWELL THAT COULD ACCOMPANY THE LIGHT WIND-WAVES. THIS MAY INDUCE ENHANCED SHOALING PROCESSES IN SHALLOW WATER AREAS. ISOLATED TO SCATTERED SHOWERS AND TSTMS WILL REMAIN IN THE EXTENDED MARINE FORECAST BASED ON EXPECTED ATMOSPHERIC MOISTURE AVAILABILITY. && .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...MJC NEAR TERM...JDW SHORT TERM...MJC LONG TERM...MJC AVIATION...43

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