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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 251703
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1203 PM EST SUN JAN 25 2015

.SYNOPSIS...
HIGH PRESSURE WILL SLIDE ACROSS THE GULF COAST STATES AND OFF THE
SOUTHEAST COAST TODAY. MEANWHILE...LOW PRESSURE WILL DROP
SOUTHEAST FROM THE MIDWEST INTO THE LOWER OHIO VALLEY. THAT LOW
WILL CROSS THE AREA LATE TONIGHT INTO MONDAY MORNING...THEN RAPIDLY
INTENSIFY OFF THE MID ATLANTIC AND NEW ENGLAND COASTS MONDAY AFTERNOON
INTO TUESDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATE MORNING ANALYSIS DEPICTS CLIPPER SYSTEM NOW OVER SOUTHERN
IL...WITH HIGH PRESSURE OVER THE GULF OF MEXICO. SKIES AVG MOSTLY
SUNNY OVER MOST OF THE CWA...WITH A SMALL AREA OF MOSTLY CLOUDY
SKIES (CIGS AROUND 15 K FT) OVER THE FAR WRN/NW ZONES. ADJUSTED
CLOUDS AND TEMPS SLIGHTLY...BUT OVERALL NOT MUCH CHANGE TO
PREVIOUS THINKING. RAISED HIGHS A DEGREE OR TWO FOR CENTRAL AND SE
VA WHERE SKIES WILL AVG MAINLY SUNNY. HIGHS INTO THE MID TO
PERHAPS UPPER 50S IN A FEW SPOTS. HIGHS IN THE UPPER 40S TO LOWER 50S
ACRS THE NORTH UNDER PARTLY SUNNY SKIES.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...

-- Changed Discussion --
...HAVE RAISED A WINTER STORM WATCH FOR THE MD ERN SHORE MON NIGHT
INTO TUE...

CONTINUING TO EVALUATE 12Z MODELS COMING IN...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). GENLY WE ARE FAVORING A
BLEND OF THE 12Z NAM/09Z SREF/00Z ECMWF OVER THE GFS AS THIS AREA
OF QPF DOES NOT NOT MAKE SENSE GIVEN THE POSITION OF THE OFFSHORE
SYSTEM. WILL BE CONSIDERING A POTENTIAL WINTER STORM WATCH FOR A
FEW OTHER ZONES OVER NE PORTIONS OF THE CWA THAT ARE NOT IN THE
CURRENT WATCH (MAINLY THE NRN NECK/MIDDLE PENINSULA/VA ERN SHORE) BUT
WOULD LIKE TO SEE THE 12Z ECMWF BEFORE DOING SO).

PREV DISC...
ACTIVE PATTERN IN THE SHORT TERM...GENERAL PATTERN IS AGREED UPON
BY THE LATEST 00Z SUITE OF MODELS...BUT WITH DIFFERENCES IN
PLACEMENT OF THE EVENTUAL TRACK OF THE SFC LO (AND ITS STRENGTH)
OFF THE MID ATLC AND NEW ENGLAND CSTS LATE MON THRU TUE...LEADING
TO SUBSTANTIAL DIFFERENCES IN SENSIBLE WX...MAINLY POTENTIAL SNOW
AMOUNTS FOR THE REGION MON EVENG THRU TUE. 00Z ECMWF/GFS MODELS
ARE THE MOST AGGRESSIVE AT DEVELOPING A CUTOFF UPPER LOW IN THE
VICINITY OF THE DELMARVA MON NIGHT/TUE...WHILE THE NAM IS WEAKER
WITH THIS FEATURE.

MAIN THEME FOR TNGT INTO MON AFTN IS A SLOWER ARRIVAL OF PCPN AND
COLD AIR...THUS MOST OF THE CWA WILL SEE RAIN THROUGH MOST OF THE
DAY MON...RATHER THAN SNOW. HAVE ADJUSTED POPS AND WX GRIDS SLGTLY
TO REFLECT THIS CHANGE. WILL CARRY HIGH CHC TO LIKELY POPS (HIGHER
NRN AND WRN COUNTIES) AFTR MIDNGT TNGT THROUGH MON MORNG. LOWS
TNGT RANGING FM THE MID 30S N...TO THE UPR 30S/NEAR 40 S. CONFIDENCE
IN THE MON NGT TO TUE PERIOD REMAINS BELOW AVG GIVEN THE MAJOR
MODEL DISCREPANCIES. AT THIS TIME...GOING WITH A BLEND OF THE 00Z
ECMWF/GFS THRU TUE...WHICH IS CLOSE TO WPC FCSTS. THESE MODEL
SOLUTIONS WOULD RESULT IN MOST OF THE CWA SEEING A GOOD CHC FOR
AT LEAST LIGHT SNOW ACCUMULATIONS MON NGT INTO TUE MORNG...WITH
THE MOST UNCERTAINTY OVER THE ERN 1/3 OF THE CWA WHERE SIGNIFICANT
SNOW ACCUMULATIONS WILL BE POSSIBLE...ESPLY OVR THE LWR MD AND VA
ERN SHR. WILL CARRY LIKELY POPS NE/E TO HI CHC ELSEWHERE MON AFTN
THROUGH MON NGT INTO TUE MORNG. HIGHS ON MON WERE RAISED A BIT
INTO THE UPR 40S TO LWR 50S ACRS THE SE...WITH UPR 30S TO MID 40S
OVR THE NRN HALF OF THE REGION. TEMPS WILL LIKELY FALL LATER IN
THE AFTN INTO THE EVENG...WITH PCPN TYPE BECOMING MAINLY SNOW
FM NW TO SE LATE MON AFTN THRU MON EVENG. LOWS MON NGT RANGING FM
THE MID 20S EXTRM NW TO THE MID 30S EXTRM SE. HIGHS ON TUE IN THE
30S TO NEAR 40.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LOW PRESSURE DEEPENS AND LIFTS AWAY FROM THE MID-ATLANTIC COAST TUES
NIGHT AS THE DEEP/ANOMALOUS NRN STREAM TROUGH REMAINS OVER THE LOCAL
AREA. THE TROUGH AXIS PROGGED TO PUSH OFFSHORE WEDS RESULTING IN
NWLY FLOW ALOFT. DISTURBANCES IN THE NWLY FLOW ALOFT WILL TRAVERSE
THE LOCAL AREA WEDS...BUT HIGH PRESSURE BUILDING IN AT THE SFC AND
DRYING CONDITIONS ALOFT WILL KEEP THE FORECAST DRY. CAA WILL RESULT
IN H85 TEMPS FALLING TO AROUND -6 TO -10C DURING THE DAY...YIELDING
TEMPS IN THE MID-UPPER 30S. COLDER TEMPS OVER THE ERN SHORE...WITH
HIGHS IN THE LOW 30S. UPPER/SFC HIGH PRESSURE BUILDS OVER THE REGION
WEDS NIGHT AS THE NEXT SHORTWAVE AND ASSOCIATED SFC LOW APPROACH
FROM THE WEST ON THURS. SFC LOW AND TRAILING COLD FRONT CROSS THE
REGION THURS NIGHT-FRI MORNING. WHILE THE STRONGEST HEIGHT FALLS ARE
EXPECTED TO CROSS THE REGION...BEST MOISTURE PROGGED TO BE ACROSS
THE NE. WILL CARRY CHANCE POPS GENERALLY NORTH AND EAST OF RICHMOND
THURS NIGHT AND SLIGHT CHANCE SOUTH AND WEST. THERMAL PROFILES...LOW
TEMPS AND AIR MASS SUPPORT PREDOMINATELY RAIN ATTM...BUT RAIN/SNOW
MIX IS POSSIBLE OVER THE NE ZONES. DRYING FRI AS HIGH PRESSURE
BUILDS INTO THE REGION. THEREAFTER...MODELS COMPETING ON WHICH
STREAM WINS THRU THE WEEKEND. GFS FAVORS A SRN STREAM SYSTEM WITH
THE ECMWF FAVORING A NRN STREAM SYSTEM.

TEMPS GENERALLY NEAR NORMAL THURS-FRI...DROPPING INTO THE UPPER
30S-LOW 40S SAT.

&&

.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
AS OF 725 AM EST...VFR CONDS ACROSS AREA TERMINALS, WITH A CLEAR
SKY EXPECTED THROUGH MIDDAY. MID TO HIGH CLOUDS INCREASE LATE THIS
AFTN AND THIS EVENING AHEAD OF NEXT CLIPPER SYSTEM APPROACHING
FROM THE NW. WINDS REMAIN W-SW AOB 10KT.

OUTLOOK: ANOTHER WEATHER SYSTEM WILL IMPACT THE AREA MONDAY INTO
TUESDAY. THIS COULD AGAIN CAUSE SOME MVFR TO IFR CEILINGS ALONG
WITH A CHANCE FOR SOME WINTRY PRECIPITATION...MOST LIKELY RAIN
SHOWERS CHANGING TO SNOW SHOWERS MONDAY AFTERNOON INTO TUESDAY.
SOME ACCUMULATING SNOW WILL BE PSBL ESPECIALLY AT SBY MONDAY NIGHT
THROUGH MIDDAY TUESDAY. HIGH PRESSURE BUILDS OVER THE REGION FROM
THE WEST FOR MID TO LATE WEEK...WITH VFR CONDITIONS EXPECTED FOR
MUCH OF THE PERIOD.

&&

.MARINE...
AS OF 725 AM EST...LATEST WX ANALYSIS FEATURES DEEPENING AREA OF LOW
PRESSURE NOW WELL NE OF THE WATERS OVER ATLANTIC CANADA THIS
MORNING...AS HIGH PRESSURE BUILDS OVER THE SOUTHEAST COAST. EXPECT
IMPROVING CONDITIONS OVER THE WATERS TODAY AS SFC HIGH CONTINUES
TO BUIOLD TO THE SOUTH...EXTENDING NWD OVER THE WATERS. FLOW
BECOMES SLY DURING THE AFTERNOON AOB 10KT...AND SEAS WL SUBSIDE TO
2-4FT BY AFTN.

GRADUALLY DETERIORATING CONDITIONS EXPECTED LATE TONIGHT THROUGH
TUESDAY AS THE NEXT IN A SERIES OF CLIPPER SYSTEMS APPROACHES FROM
THE WEST ON MON. THE LOW IS THEN EXPECTED TO STRENGTHEN RAPIDLY
AS IT LIFTS NWD ALONG THE COAST. MODELS HAVE COME INTO BETTER
AGREEMENT WITH HANDLING THIS SYSTEM, QUICKLY BUILDING WINDS AND
SEAS MONDAY NIGHT. STRONG SCA CONDITIONS CONTINUE TO APPEAR
CERTAIN FOR ALL WATERS...WITH CONFIDENCE REGARDING LOW END GALE
CONDITIONS INCREASING...ESPECIALLY OVER THE NORTHERN AND CENTRAL
COASTAL WATERS. THE RESULT WILL BE AN EXTENDED PERIOD OF SCA
CONDITIONS OVER THE WATERS. DUE TO ONGOING SCA, WILL WAIT UNTIL
CURRENT HAZARDS EXPIRE BEFORE HOISTING NEW FLAGS. BEST CHANCE FOR
GALES WILL BE MON NIGHT WITH SCA CONDITIONS PERSISTING THRU TUES
NIGHT. DECIDED TO FOREGO GALE WATCH HEADLINE FOR NOW WITH LIKELY
TIME PERIOD OF GALES 4 FORECAST PERIODS AWAY. EITHER WAY, WINDS
TO START TO DROP OFF WED/WED NGT AS SFC HIGH PRESSURE BUILDS
FROM THE OHIO VALLEY, WITH WINDS BECOMING SSW THURSDAY AS HIGH
SLIPS OFFSHORE. SEAS WL TAKE AWHILE TO DROP OFF, AND WL LKLY REMAIN
ELEVATED AOA 5 FT THRU THE DAY WEDS. NEXT SYSTEM SET TO CROSS THE
WATERS THURS NIGHT. SCA CONDITIONS APPEAR POSSIBLE YET AGAIN WITH
FRONTAL PASSAGE THU NGT/FRI.

&&

.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...
-- Changed Discussion --
MD...WINTER STORM WATCH FROM MONDAY EVENING THROUGH TUESDAY
     AFTERNOON FOR MDZ021>025.
NC...NONE.
VA...NONE.
MARINE...NONE.
-- End Changed Discussion --

&&

$$
SYNOPSIS...LKB
NEAR TERM...LKB/TMG
SHORT TERM...LKB/TMG
LONG TERM...SAM
AVIATION...MAM
MARINE...MAM
TIDES/COASTAL FLOODING...AKQ