Area Forecast Discussion
Issued by NWS Wakefield, VA

Home | Current Version | Previous Version | Text Only | 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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KAKQ 182321 AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 721 PM EDT SAT OCT 18 2014 .SYNOPSIS... COOL CANADIAN HIGH PRESSURE BUILDS IN FROM THE NORTHEAST TONIGHT THROUGH SUNDAY...AND BECOMES CENTERED OVER THE REGION LATER SUNDAY INTO MONDAY. LOW PRESSURE MOVES INTO THE REGION MONDAY NIGHT AND TUESDAY. && .NEAR TERM /UNTIL 6 AM SUNDAY MORNING/... POTENT SHORTWAVE PUSHES THE TROUGH AXIS ACROSS THE REGION OVERNIGHT. MOISTURE REMAINS LIMITED...BUT THE STRENGTH OF THE UPPER VORT AND THE PRESENCE OF MODEST LOW-LEVEL MOISTURE MAY BE ENOUGH FOR A FEW SPRINKLES. WL KEEP POPS OUT WITH CHCS FOR MEASURING <10%. WINDS NNW AT 5-10 KT AND A PARTLY TO MOSTLY CLOUDY SKY SHOULD YIELD LOW TEMPS IN THE L-M40S INLAND AND UPPER 40S TO LOW 50S NEAR THE COAST. && .SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/... SHORTWAVE PUSHES OFFSHORE OF THE MID-ATLANTIC COAST BY 12Z SUNDAY MORNING, AS COOL CANADIAN HIGH PRESSURE SURGES INTO THE REGION IN ITS WAKE FOR LATER SUNDAY AND MONDAY. CAA WANES AS PRES GRADIENT RELAXES...BUT NW FLOW ALOFT AND HIGH PRESSURE AT THE SFC BUILDING IN FROM THE WEST RESULT IN A COOLER, ALBEIT PARTLY TO MOSTLY SUNNY DAY ACROSS THE LOCAL AREA ON SUNDAY. LOCAL THICKNESS TOOL YIELD TEMPS IN THE LOW- MID 60S...NEARLY 1 STD DEV BELOW NORMAL. TEMPERATURES DROP QUICKLY SUN DAY NIGHT AS SFC HIGH BECOMES CENTERED OVER THE COASTAL PLAIN. GIVEN MOSTLY CLR SKY AND WINDS BECOMING CALM/LIGHT, AND FALLING DEW POINTS INTO THE LOW 30S...GOOD RADIATING CONDITIONS ARE EXPECTED AND SHOULD RESULT IN THE COLDEST TEMPS OF THE SEASON THUS FAR. MODEL GUIDANCE A BIT QUICKER TO INDICATE INCREASING WAA TOWARDS DAWN MONDAY MORNING, SO A MINOR UPWARD ADJUSTMENT TO FORECAST LOWS WAS MADE. STILL EXPECTING LOWS INTO THE MID TO UPPER 30S IN MOST SPOTS INLAND SUNDAY NIGHT, WHILE TEMPS ALONG THE IMMEDIATE COAST DROP ONLY INTO THE LOW-MID 40S. COULD SEE SOME PATCHY FROST IN MORE SHELTERED LOCALES EARLY MONDAY MORNING, AND WILL CONTINUE MENTION IN HWO FOR NOW. HIGH PRESSURE PUSHES FARTHER OFFSHORE MONDAY AS FLOW RETURNS TO THE SOUTH-SOUTHWEST. ONGOING WEAK WAA AND MODEST HEIGHT RISES YIELD SLIGHTLY MILDER TEMPS MONDAY...WITH HIGHS IN THE MID-UPPER 60S UNDER PARTLY CLOUDY SKIES. NEXT UPPER TROUGH/CLIPPER LOW DROPS SOUTH FROM THE UPPER MIDWEST MONDAY, AND DIGS ACROSS THE GREAT LAKES REGION INTO THE OH VALLEY MONDAY NIGHT AS THE ASSOCIATED COLD FRONT APPROACHES THE REGION. REMOVED ANY POP MENTION ON MONDAY. WHILE MODELS DO SEEM INTENT ON SOME VERY LIGHT QPF AFTER 18Z, OVERRUNNING MOISTURE ASSOCIATED WITH CLIPPER LOW LKLY NOT ENOUGH INITIALLY TO OVERCOME ANTECEDENT DRY AIR IN PLACE UNTIL LATE MONDAY NIGHT/EARLY TUESDAY. WILL CONTINUE WITH LOW CHANCE POPS AFTER 12Z TUE. HIGHS MONDAY IN THE MID TO UPPER 60S...WITH MILDER EARLY MORNING LOWS IN THE LOW 50S TO NEAR 60 MONDAY NIGHT. UPPER LOW LOOKS TO SLIDE ACROSS THE NORTHERN MID-ATLANTIC ON TUESDAY, WITH SCT SHRAS EXPECTED (MAINLY NORTH) TUESDAY AS VORT LOBE SWINGS ACROSS THE REGION. OTHERWISE, HIGHS IN THE U60S TO L70S ARE EXPECTED UNDER A PARTLY TO MOSTLY SUNNY SKY. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... WILL GO CLOSER TO THE 12Z ECMWF FOR THE EXTENDED PERIOD. DRY COLD FRONT SWINGS ACRS THE AREA LATE FRI NGT THRU SAT...BRINGING JUST A FEW CLOUDS AT MOST. BUT MORE IMPORTANTLY...DRIER AIR WILL FILTER IN BEHIND THE FRONT. HI PRES WILL THEN BLD INTO AND OVR THE AREA FOR SUN THRU MON...PROVIDING DRY AUTUMN WX WITH TEMPS JUST A DEGREE OR TWO BELOW NORMAL. ANOTHER COLD FRONT WILL MOVE INTO AND ACRS THE REGION MON NGT THRU TUE. FOR NOW...WILL HAVE JUST SLIGHT CHC OF SHOWERS EVERYWHERE DURING THIS TIME PERIOD...DUE TO QUESTIONABLE TIMING OF THE FRONT AND ASSOCIATED MOISTURE WITH IT. MIN TEMPS WILL BE IN THE 50S SAT MORNING...RANGE FM THE MID 40S TO THE MID 50S SUN AND MON MORNINGS...AND RANGE FM THE UPR 40S TO MID 50S TUE MORNING. MAX TEMPS WILL BE IN THE LWR TO MID 70S SAT...AND RANGE FM THE MID 60S TO ARND 70 SUN...MON AND TUE. && .AVIATION /23Z SATURDAY THROUGH THURSDAY/... THE CU DECK IS DEVELOPING ON TIME WITH SCT-BKN050 ACROSS CENTRAL VA AND GRADUALLY SPREADING EAST TO THE COAST. EXPECT THE SCT-BKN DECK TO LINGER FOR THE REMAINDER OF THE DAY AND A LITTLE INTO THE OVERNIGHT HOURS. THE INITIAL COLD FRONT CROSSED THROUGH THE TAF SITES LATE THIS MORNING AND WINDS SHIFTED TO THE WNW AT 15 KT WITH GUSTS TO AROUND 20 KT. WINDS WILL BECOME MORE NW TONIGHT AND AVG AROUND 10 TO 15 KT. OUTLOOK...DRY/VFR CONDITIONS SUN/MON WITH FAIRLY LIGHT FLOW AROUND 10 KT OR LESS FROM MIDDAY SUN ONWARD. NEXT SYSTEM TUE-WED WILL BRING A CHANCE FOR SHOWERS AND POSSIBLY MVFR CIGS/VSBYS. SW FLOW EARLY TUE SHIFTS TO THE NW AND BECOMES SOMEWHAT STRONG/GUSTY LATE TUE THROUGH WED. && .MARINE... SCA HEADLINES WERE RAISED OVER THE BAY WITH SCA CONDITIONS EXPECTED BY LATE AFTERNOON AS A COLD FRONT PUSHED ACROSS THE AREA. SEAS ARE STILL AROUND 5 FEET WELL OFFSHORE SO SCA HEADLINES FOR COASTAL WATERS WILL CONTINUE TODAY/TONIGHT/SUN (LINGERING INTO SUN EVENING N OF PARRAMORE ISLAND). MORE SIGNIFICANT WINDS WILL DEVELOP THIS EVENING AND OVERNIGHT AND WILL LAST THROUGH SUN MORNING IN THE WAKE OF THE SFC COLD FRONT AS STRONG CAA PUSHES OVER THE RELATIVELY WARM WATERS. WINDS OVER THE BAY AND OCEAN ARE EXPECTED TO INCREASE TO AROUND 25 KT SUSTAINED WITH FREQUENT GUSTS TO AROUND 30 KT (AN OCCASIONAL GUST CLOSE TO GALE FORCE WILL BE POSSIBLE FROM ABOUT 06-12Z BUT NOT ENOUGH TO WARRANT GALES). WINDS WILL BE A FEW KNOTS LESS ACRS THE RIVERS AND CURRITUCK SOUND (SUSTAINED WINDS AROUND 20 KT WITH GUSTS TO 25 KT). WAVES ARE EXPECTED TO BUILD TO 4 FT ON THE BAY. SEAS WILL BUILD TO 5-6 FT ON THE OCEAN OFFSHORE BUT GENLY REMAIN CAPPED AT AROUND 4 FT NEARSHORE DUE TO OFFSHORE NW FLOW. RIVERS WILL SEE WAVES AROUND 2 FT...ALTHOUGH THE JAMES WILL LIKELY REACH 2-3 FT. HAVE HELD OFF ON SCA HEADLINES FOR THE BAY/RIVERS/SOUND UNTIL CURRENT ONES EXPIRE...BUT CONFIDENCE IS HIGH FOR SCA CONDITIONS. THE HIGH CENTER BUILDS OVER THE WATERS SUN NIGHT/MON...ALLOWING SUB- SCA CONDITIONS TO RETURN. WHILE THERE REMAINS SOME MODEL UNCERTAINTY...THE NEXT COLD FRONT IS EXPECTED TO CROSS THE WATERS LATE TUES...ACCOMPANIED BY CAA AND MORE SCA CONDITIONS. SYSTEM IS EXPECTED TO STALL OFF THE COAST THRU THE END OF THE WEEK...WHICH MAY RESULT IN A PROLONGED PERIOD OF SCA CONDITIONS. && .FIRE WEATHER... HAVE HIGHLIGHTED BREEZY/DRY CONDITIONS IN FIRE WEATHER FORECAST. MIXED LAYER DEWPOINTS INDICATE DEWPOINTS IN THE LOW TO MID 30S OVER NORTHERN SECTIONS TOMORROW AFTN. THIS, IN TANDEM WITH DRYING FUELS AND STILL-GUSTY NNW WINDS BEHIND THE FRONT OVER EASTERN SHORE ZONES WILL YIELD RH IN THE 35% RANGE AND WINDS THAT APPROACH CRITICAL THRESHOLDS. CERTAINLY WORTH HIGHLIGHTING THE THREAT, ESPECIALLY IN LIGHT OF THE DRY FROPA THIS AFTN. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...NONE. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT SUNDAY FOR ANZ635>638. SMALL CRAFT ADVISORY UNTIL 4 PM EDT SUNDAY FOR ANZ630>634. SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR ANZ654-656-658. SMALL CRAFT ADVISORY UNTIL 10 PM EDT SUNDAY FOR ANZ650-652. && $$ SYNOPSIS...MAM NEAR TERM...MPR/MAM SHORT TERM...MAM/SAM LONG TERM...JDM AVIATION...JAO MARINE...JDM FIRE WEATHER...

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