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 260249 AFDILM AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WILMINGTON NC 1049 PM EDT SAT MAY 25 2013 .SYNOPSIS... DRY AND COOL CANADIAN AIR WILL PREVAIL ACROSS THE REGION THROUGH THE MEMORIAL DAY WEEKEND. A WARMING TREND WILL BEGIN ON MONDAY...CONTINUING THROUGH THE UPCOMING WEEK...WITH MINIMAL RAINFALL CHANCES. DAYTIME TEMPERATURES MAY RISE ABOVE NORMAL WEDNESDAY THROUGH FRIDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
AS OF 1030 PM SATURDAY...VIA LATEST SATELLITE IMAGERY...SKIES EAST OF THE MOUNTAINS CONTINUE WITH THIN UPPER LEVEL CLOUDINESS...WITH SOME PATCHES OF OPAQUE CIRRUS. LATEST MODELS INDICATE A COUPLE SHEAR VORTS WITHIN NW FLOW TO PUSH ACROSS THE AREA LATE TONIGHT THROUGH SUNDAY. THESE VORTS MAY HAVE ENOUGH MOISTURE TO PRODUCE OPAQUE ALTOCU BUT REALLY DO NOT SEE THAT HAPPENING UNTIL AROUND OR AFTER DAYBREAK SUN. THE SCOURING DOWNSLOPE TRAJECTORY OF THE FLOW UPSTAIRS WILL BE WORKING AGAINST ANY MOISTURE AFTER CROSSING THE APPALACHIANS. BASICALLY WILL STICK WITH A MOSTLY CLEAR FCST FOR THE OVERNIGHT. TONIGHTS MINS LOOK ON CUE...WITH UPPER 40S INLAND...50 TO 55 AT THE COAST. A DECENT SFC BASED INVERSION HAS DEVELOPED AFTER SUNSET WITH DECOUPLING OF THE WINDS SOON TO FOLLOW. AS A RESULT...DECENT RADIATIONAL COOLING SHOULD OCCUR THE REMAINDER OF TONIGHT...ALLOWING TONIGHTS MINS TO RANGE FROM THE UPPER 40S INLAND...TO 50 TO 55 AT THE COAST.
-- End Changed Discussion --
&& .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/... AS OF 300 PM SATURDAY...DRY AND SEASONABLE WEATHER FOR THE EXTENDED HOLIDAY WKND WITH SEASONABLE TEMPS AND PARTLY/MOSTLY SUNNY SKY CONDITIONS. BROAD CYCLONIC FLOW AT 500MB WILL GRADUALLY GIVE WAY TO A MORE ZONAL PATTERN DURING MONDAY. WHILE THIS KEEPS THE MID LEVEL WINDS W/NW...A COOL BUT DRYING DIRECTION...SUBTLE HEIGHT RISES WILL AID IN TEMPERATURE RECOVERY BY MONDAY. AT THE SURFACE...HIGH PRESSURE WILL DRIFT OVERHEAD DURING SUNDAY BEFORE TAKING UP A POSITION OFFSHORE INTO MONDAY WITH SW RETURN FLOW FLOODING INTO THE AREA. TEMPS SUNDAY WILL RISE TO AROUND OR JUST BELOW 80 DEGREES...THEN BUMP A FEW DEGREES WARMER FOR MEMORIAL DAY WHEN MOST LOCATIONS AWAY FROM THE BEACHES WILL RISE INTO THE LOW 80S. SUNDAY NIGHT WILL AGAIN BE COOL...MID 50S ACROSS THE AREA...BUT THE WARM RETURN FLOW MONDAY NIGHT WILL KEEP MINS FROM FALLING OUT OF THE LOWER 60S. WHILE PRECIP CHANCES WILL BE QUITE LOW CANNOT ENTIRELY RULE OUT AN ISOLATED SHOWER DURING MONDAY. INCREASED SURFACE TEMPS CREATE SOME ENHANCED INSTABILITY WHICH WILL TRIGGER CONVECTIVE CLOUDS...AND MAYBE A SHOWER. HOWEVER...NW FLOW ABOVE 800MB IS A DRYING FLOW...AND 700MB THERMAL RIDGE REMAINS DISPLACED SLIGHTLY WEST OF SURFACE HIGH LEADING TO A WEAK INVERSION IN THE 800-700MB LAYER. THIS WILL PRECLUDE WIDESPREAD CONVECTION...BUT A FEW SHOWERS ARE POSSIBLE...ESPECIALLY ALONG THE SEA BREEZE BOUNDARY WHERE SURFACE CONVERGENCE MAY BE ENOUGH TO SEND PARCELS THROUGH THIS CONVECTIVE LID. && .LONG TERM /TUESDAY THROUGH SATURDAY/... AS OF 300 PM SATURDAY...MEDIUM RANGE GUIDANCE REMAINS CONSISTENT IN BUILDING AN ANOMALOUS RIDGE OVER THE EAST COAST WITH TROUGHING OUT WEST. ANOMALY IS NOT THE MOST IMPRESSIVE WITH HEIGHTS NEAR TWO STANDARD DEVIATIONS ABOVE NORMAL. THE SAME MODEL SUITE IS SHOWING THE WARMER 850MB TEMPERATURES CONFINED TO AREAS NORTH OF US IN THE MID ATLANTIC STATES. THIS SEEMS REASONABLE LOOKING AT MODEL GUIDANCE AND WPC NUMBERS WHICH ONLY SHOW MODEST WARMING THROUGHOUT THE PERIOD. THE CWA REMAINS VOID OF ANY FORECAST MAX TEMPERATURES AT OR ABOVE 90 DEGREES. SLIGHT CHANCE POPS REMAIN IN THE FORECAST TUESDAY THEN DRY CONDITIONS THROUGH THE REMAINDER OF THE PERIOD. && .AVIATION /03Z SUNDAY THROUGH THURSDAY/... AS OF 00Z...VFR EXPECTED THROUGH THIS TAF PERIOD...WITH SCATTERED MID-LEVEL CLOUDS ALONG WITH PERIODS OF SCATTERED TO BROKEN CIRRUS. BECAUSE OF THE DRY AIRMASS DO NOT EXPECT FOG TO BE AN ISSUE OVERNIGHT. WITH HIGH PRESSURE OVER KFLO/KLBT TERMINALS HAVE INDICATED LIGHT/VARIABLE WINDS THROUGH THE TAF PERIOD. LIGHT/VARIABLE WINDS AT THE COASTAL TERMINALS OVERNIGHT WILL BECOME NW-NE AFTER THE INVERSION BREAKS 13-14Z. WINDS WILL THEN BECOME SOUTHEAST TO SOUTH AS THE SEA BREEZE KICKS IN BY AFTERNOON. FEW-SCT CUMULUS CAN BE EXPECTED WITH THE SEA BREEZE. EXTENDED OUTLOOK...EARLY MORNING FOG WILL RESTRICT VSBYS TO MVFR/IFR MONDAY THROUGH THURSDAY AT KFLO/KLBT. OTHERWISE VFR. && .MARINE...
-- Changed Discussion --
NEAR TERM /THROUGH TONIGHT/... AS OF 1030 PM SATURDAY...MODELS INDICATE A BUBBLE TYPE SFC HIGH TO BREAK OFF FROM THE MAIN RIDGING THAT EXTENDS FROM THE GREAT LAKES. THIS WILL ADD SOME CONFUSION TO FORECASTING A WIND DIRECTION FOR THE OVERNIGHT AND SUBSEQUENT PERIODS. WITH THE SFC PG RELAXED SPEEDS WILL ONLY BE AROUND 10 KT OR LESS. SIGNIFICANT SEAS WILL RUN 2 TO 3 FT...AND BE DOMINATED BY A 2 TO 3 FT EASTERLY SWELL AT 8 TO 9 SECOND PERIODS. THE SHOALS AND LONGER SHELF WATERS WILL KEEP SEAS AROUND 2 FT SOUTH OF LITTLE RIVER INLET TO SOUTH SANTEE RIVER. SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... AS OF 300 PM SATURDAY...HIGH PRESSURE WILL DRIFT ACROSS THE WATERS SUNDAY...SETTLING IN A POSITION JUST NE OF THE LOCAL WATERS ON MONDAY. THIS WILL CONTINUE A RELATIVELY LIGHT PRESSURE GRADIENT...AND ALTHOUGH WINDS WILL BE 10 KTS OR LESS THROUGH THE PERIOD...THEY WILL GRADUALLY GO FROM VARIABLE...TO A PREDOMINANT SOUTHERLY DIRECTION LATE MONDAY. WITH THE WEAK GRADIENT AND LIGHT WINDS...SEAS WILL BE PRIMARILY SWELL-DRIVEN...WITH A 2FT/9SEC SE SWELL PRODUCING 1-3 FT WAVES BOTH DAYS. LONG TERM /TUESDAY THROUGH THURSDAY/... AS OF 300 PM SATURDAY... TYPICAL SUMMER PATTERN WILL ALLOW FAVORABLE CONDITIONS FOR THE MARINE COMMUNITY. MID LEVEL RIDGING WILL BUILD OVER THE MID ATLANTIC STATES WITH THE SURFACE RIDGE AXIS BASICALLY OVER THE COASTAL WATERS. SOUTH TO SOUTHEAST WINDS OF 10-15 KNOTS WILL PREVAIL. WAVEWATCH BULLETINS CONTINUE TO BE VOID OF ANY APPRECIABLE SWELL COMPONENT AND SIGNIFICANT SEAS CAN BE EXPECTED TO HOLD IN A 2-4 FOOT RANGE.
-- End Changed Discussion --
&& .ILM WATCHES/WARNINGS/ADVISORIES... SC...NONE. NC...NONE. MARINE...NONE. && $$ SYNOPSIS...JDW NEAR TERM...DCH SHORT TERM...JDW LONG TERM...SHK AVIATION...MRR MARINE...

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