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 252102 AFDAKQ AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE WAKEFIELD VA 402 PM EST SUN JAN 25 2015 .SYNOPSIS... LOW PRESSURE OVER THE LOWER OHIO VALLEY WILL WEAKEN ACROSS THE SOUTHERN APPALACHIANS LATER TONIGHT INTO MONDAY MORNING. A NEW LOW PRESSURE SYSTEM WILL DEVELOP OFF THE COASTAL CAROLINAS MONDAY MORNING...AND RAPIDLY INTENSIFY OFF THE MID ATLANTIC COAST MONDAY NIGHT. THE LOW WILL CONTINUE TO PULL OFF TO THE NORTHEAST OF THE AREA THROUGH TUESDAY. && .NEAR TERM /UNTIL 6 AM MONDAY MORNING/... AFTN WX ANALYSIS DEPICTS CLIPPER SYSTEM NOW OVER THE LOWER OHIO VALLEY...WITH HIGH PRESSURE CENTERED FROM THE ROCKIES TO THE SRN PLAINS. MILD/MOSTLY SUNNY CONDITIONS ACRS THE LOCAL AREA WITH MAIN CLOUD/PRECIP SHIELD IN ASSOCIATED WITH THE CLIPPER STILL WELL TO OUR NORTH. TEMPERATURES ARE GENLY IN THE 50S (UPPER 40S FAR NORTH AND ALONG THE IMMEDIATE COAST). QUIET EVENING WITH JUST A SLOW INCREASE IN CLOUDS AS THE CLIPPER SYSTEM WILL BE SLOW TO ADVANCE TO EAST. HAVE SCALED BACK ON POPS UNTIL WELL AFTER MIDNIGHT FOR MOST AREAS. ALSO...DEEP LIFT/UVM ASSOCIATED WITH THE CLIPPER SYSTEM IS FORECAST TO WEAKEN AS THE SFC LOW REACHES THE APPALACHIANS...AND MAIN ENERGY TRANSFERS TO DEVELOPING SFC LOW OFF THE COASTAL CAROLINAS. THUS...WILL CONFINE LIKELY POPS TO THE FAR WEST AND NORTH...AND EVEN HERE ONLY EXPECTING LIGHT RAIN ON THE ORDER OF 0.10" OR LESS. LOWS IN THE MID-UPPER 30S /ABOVE FREEZING ALL AREAS SO NO P-TYPE CONCERNS OVERNIGHT. && .SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/... ...HAVE RAISED A WINTER STORM WATCH FOR THE MD ERN SHORE MON NIGHT INTO TUE... FAVORING A BLEND OF THE 12Z NAM/ECMWF AND 15Z SREF THIS PERIOD. HAVE NOTED 12Z GFS HAS A SPURIOUS LOOKING BULLSEYE OF QPF OVER PORTIONS OF THE CWA WEST OF THE BAY MON NIGHT/EARLY TUE. THE 06Z GFS HAD THIS AS WELL (ALTHOUGH A BIT FARTHER TO THE SOUTH). FOR MON...THE ENERGY WILL CONTINUE TO TRANSFER TO THE OFFSHORE SFC LOW AND MUCH OF THE AKQ CWA WILL BE IN SORT OF A LULL WITH FAIRLY WEAK LIFT DESPITE MAINLY CLOUDY SKIES. STILL HAVE LIKELY POPS ACRS THE NORTH AND CHC POPS SOUTH ON MON...JUST DO NOT EXPECT MUCH IN THE WAY OF QPF. HIGH TEMPERATURES HAVE BEEN RAISED A FEW MORE DEGREES FROM PREVIOUS FORECAST...INTO THE MID 50S IN NE NC...TO THE LOWER 40S OVER THE FAR NORTHERN TIER. WE WENT CLOSER TO THE MET NUMBERS DUE TO A LACK OF FAITH IN THE GFS MODEL THIS CYCLE. THE MAIN EVENT FOR OUR AREA BEGINS MON NIGHT...AS COLDER AIR PLUNGES SOUTH IN RESPONSE TO RAPID INTENSIFICATION OF THE SFC LOW OFF THE VA COAST. STILL MAINLY RAIN ACRS THE SOUTHERN 2/3 OF THE CWA IN THE EVENING...BECOMING ALL SNOW BETWEEN 03-06Z FOR MOST LOCATIONS. DURING THIS TIME...BEST LIFT/FRONTOGENESIS WILL RESIDE OFF THE COAST. WILL BE RELYING ON DEFORMATION ZONE AND INTENSE BANDING DEVELOPING FROM THE DELMARVA TO LOG ISLAND TO "WRAP AROUND" AND DROP SOUTH FOR MOST OF OUR SNOW INTO THE DAY TUE. THUS...SNOW AMOUNTS WILL SHOW A SHARP CUTOFF. ANY CHANGE IN POSITION OF THIS BANDING CAN HAVE DRASTIC EFFECTS ON SNOW AMOUNTS...SO UNCERTAINTY REMAINS RATHER HIGH. HAVE FORECAST ROUGHLY 3-6" OF SNOW ON THE MD ERN SHORE IN THE WATCH AREA...WITH 2-3" ACRS NRN NECK/VA ERN SHORE (AREAS THAT WILL PROBABLY NEED AN ADVISORY)...TAPERED FAIRLY QUICK TO < 1" OVER MOST OF THE REMAINDER OF THE CWA. COULD SEE SLIGHTLY MORE THAN 1" ACRS HAMPTON ROADS EARLY TUE HOWEVER. SNOW IS EXPECTED TO TAPER OFF LATE TUE MORNING/AFTN...BUT IF ECMWF IS CORRECT THIS WOULD BE SLOWER AND ADDITIONAL SNOW AMOUNTS MAY NEED TO BE ADDED. MAV/MET GUIDANCE LOOKS TOO WARM TUE...ESPECIALLY ACRS THE NE. EXPECT HIGHS IN THE LWR 30S NE TO AROUND 40 F SW. CLEARING/COLD TUE NIGHT/WED WITH LOWS IN THE UPPER TEENS TO MID 20S AND HIGHS ON WED IN LWR 40S SW TO THE LWR 30S NE. && .LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/... LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH DRY WX MOST DAYS. FOR WED NIGHT...SFC HI PRES BLDS OVR THE MID ATLANTIC AND SE STATES AS THE NEXT LO PRES SYSTM APPROACHES FM THE W. WITH A MSTLY CLEAR SKY AND LIGHT WINDS...TEMPS WILL FALL INTO THE MID 20S IN MOST SPOTS. LO PRES AND AN ASSOCIATED MID-LEVEL VORT MAX WILL BRING PRECIP (PLAIN RAIN) INTO THE AREA STARTING LATE THU. FAVORED THE SLIGHTLY SLOWER ECMWF SOLUTION...WITH A 30% CHANCE OF PRECIP (RA/SN NORTH AND RA SOUTH) THU NIGHT...WITH LO TEMPS IN THE LO TO MID 30S. CONDS THEN DRY OUT INTO FRI AND SAT AS SFC HI PRES BLDS IN FM THE W. EXPECT A PRTLY CLOUDY SKY BOTH DAYS WITH NW WINDS AND HI TEMPS FALLING FM THE 40S ON FRI TO THE MID 30S TO LWR 40S ON SAT. && .AVIATION /21Z SUNDAY THROUGH FRIDAY/... VFR CONDITIONS PREVAIL THROUGH AT LEAST 26/1000Z TONIGHT...WITH CIGS AROUND 3 KFT AGL THEREAFTER AS PRECIPITATION ASSOCIATED WITH A CLIPPER SYSTEM MOVES INTO THE REGION FROM THE WEST. PRECIP BEGINS AS ALL RAIN AND RAINFALL RATES ARE EXPECTED TO INCREASE DURING MON AFTN...ESPECIALLY AT KRIC AND KSBY...WHICH WILL DRIVE CIGS/VIS DOWN INTO IFR/MVFR RANGES AT ALL AIR TERMINALS. RAIN IS EXPECTED TO QUICKLY TRANSITION TO SNOW...DURING EARLY MON EVENING NW AND LATE EVENING/OVERNIGHT MON NIGHT SE...THUS CAUSING OVERALL FLIGHT CONDITIONS TO DETERIORATE FARTHER. THE BIGGEST IMPACTS WILL TAKE PLACE OVER THE NRN NECK...MD/VA EASTERN SHORE...AND KSBY WHERE 1-4 INCHES OF ACCUMULATING SNOW IS ANTICIPATED TO OCCUR MON NIGHT INTO TUE MORNING BEFORE TAPERING OFF TUE AFTN. BREEZY NE WINDS EARLY MON TURN TO THE N BY MON EVENING. NW WINDS BECOME GUSTY...ESPECIALLY ALONG THE COAST...OVERNIGHT MON NIGHT AS COLD AIR ADVECTION BEGINS TO TAKE PLACE OVER THE REGION. SNOW SHOWERS SLOWLY TAPER OFF ON TUE...HOWEVER BREEZY NW WINDS WILL PERSIST TUE INTO TUE NIGHT DUE TO A LINGERING AND TIGHTENED PRESSURE GRADIENT AND CONTINUED COLD AIR ADVECTION. ALL PRECIPITATION COMES TO AN END BEFORE MIDNIGHT TUE NIGHT AND HIGH PRESSURE BUILDS INTO THE AREA FROM THE WEST. CLEARING SKIES AND A RETURN TO VFR CONDITIONS IS ANTICIPATED TUE NIGHT THROUGH EARLY THU UNDER THE INFLUENCE OF HIGH PRESSURE. && .MARINE... HEADLINES HAVE BEEN HOISTED OVR ALL WTRS FOR THE UPCOMING STRONG CSTL LO. FOR TNGT...10-15 KT SE WINDS WILL SLOWLY SHIFT TO THE E AS SFC LO PRES APPROACHES FM THE W. THE LO WILL REDEVELOP OFF THE CAROLINA CST ON MON...AND STRENGTHEN AS IT SLOWLY ADVANCES NEWRD INTO MON NIGHT. A GALE WARNG HAS BEEN ISSUED FOR CSTL WTRS N OF PARRAMORE ISLAND WHERE CONFIDENCE FOR 34+ KT WINDS IS HI ON THE BACK SIDE OF THE LO. FOR THE REMAINDER CSTL WTRS AND THE BAY...WITH THIS BEING 3RD PERIOD AND STILL SOME UNCERTAINTY...WENT AHEAD WITH A GALE WATCH FOR NOW AND WILL BE CONVERTED TO EITHER A GALE WARNG OR SCA IN FUTURE UPDATES. OTWS...WENT WITH A SCA FOR THE SOUND AND RIVERS. ANOTHER THING OF NOTE IS SEAS WITH THIS EVENT...EXPECTED TO RISE TO AT LEAST 12 FT OUT 20NM OVR NRN CSTL WTRS. WAVES OVR THE BAY UP TO 5-6 FT. NW FLOW AND MARGINAL SCA CONDS MAY CONTINUE INTO TUE NIGHT/WED AS SFC HI PRES SLOWLY BLDS IN FM THE W. SUB-SCA CONDS THEN FOR WED NIGHT/THU. && .TIDES/COASTAL FLOODING... LOW PRESSURE FORECAST TO INTENSIFY RAPIDLY OFF THE MID-ATLANTIC COAST MONDAY NIGHT/TUESDAY. THE RESULT WILL BE A PERIOD OF STRONG NLY WINDS OVER THE WATERS. TIDAL ANOMALIES ARE EXPECTED TO REACH 1 TO 1.5 FT...POSSIBLY HIGHER...DURING MONDAY NIGHT AND TUESDAY MORNINGS HIGH TIDE CYCLES. SEVERAL SITES IN THE LOWER BAY WILL REACH HIGHEST ASTRO TIDE WITH WATER LEVELS APPROACHING MINOR FLOODING THRESHOLDS AT SEWELLS POINT MONDAY NIGHT. MINOR FLOODING IS ALSO POSSIBLE AT OCEAN CITY INLET. HIGH TIDES ARE EXPECTED AGAIN TUES...BEFORE ANOMALIES DROP OFF LATE TUES INTO TUES NIGHT AS THE LOW LIFTS AWAY FROM THE REGION. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY AFTERNOON FOR MDZ021>025. NC...NONE. VA...NONE. MARINE...SMALL CRAFT ADVISORY FROM 7 PM MONDAY TO 7 PM EST TUESDAY FOR ANZ635>638. GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY EVENING FOR ANZ630>632-634. SMALL CRAFT ADVISORY FROM 7 PM MONDAY TO 4 AM EST WEDNESDAY FOR ANZ633. GALE WATCH FROM MONDAY EVENING THROUGH TUESDAY EVENING FOR ANZ654-656-658. GALE WARNING FROM 4 PM MONDAY TO 10 PM EST TUESDAY FOR ANZ650- 652. && $$ SYNOPSIS...LKB NEAR TERM...LKB SHORT TERM...LKB LONG TERM...MAS AVIATION...BMD MARINE...MAS TIDES/COASTAL FLOODING...AKQ

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