-- 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