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464
FXUS61 KAKQ 212029
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
429 PM EDT TUE OCT 21 2014

.SYNOPSIS...
LOW PRESSURE AND ITS ASSOCIATED COLD FRONT MOVE INTO THE AREA THIS
EVENING...THEN PUSH OFFSHORE TONIGHT. THE LOW WILL INTENSIFY WHILE
SLOWLY TRACKING NORTHEAST OFF THE MID ATLANTIC COAST TONIGHT THROUGH
FRIDAY. COOL AND UNSETTLED CONDITIONS WILL PREVAIL ON WEDNESDAY...
FOLLOWED BY DRIER CONDITIONS THURSDAY AND FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
LATEST SFC ANALYSIS SHOWS LOW PRESSURE DEVELOPING OVER SE
PA/SOUTHERN NJ WITH A COLD FRONT EXTENDING SW FROM THIS LOW INTO
SW VA. AS THE FRONT APPROACHES THE LOCAL AREA THIS EVENING...CLOUDS
WILL CONTINUE TO INCREASE FROM WEST TO EAST. A STRONG SHORTWAVE
CURRENTLY SEEN ON WV IMAGERY OVER THE OH VALLEY IS PROGGED TO
DIVE SE AROUND THE BASE OF THE AMPLIFYING UPPER LOW...REACHING
VA/NC OVERNIGHT. THIS WILL IN TURN ALLOW A CLOSED LOW TO DEVELOP
OVER THE LOCAL AREA TONIGHT. AS THE SHORTWAVE/UPPER TROUGH
APPROACH LATE TODAY...EXPECT SHOWERS TO INITIALLY DEVELOP OVER NW
ZONES BEFORE SPREADING SOUTH/EAST OVERNIGHT. WILL CARRY 25-40%
POPS N-NW OF KRIC THROUGH 00Z. WITH THE LOW CUTTING OFF OVER US
TONIGHT...THE BEST FORCING FOR SHOWERS WILL BE ACROSS
NORTHERN/EASTERN PORTIONS OF THE FA. WILL CARRY LIKELY POPS OR
HIGH-END CHANCE POPS (50-70%) ACROSS THE NORTHERN NECK/MIDDLE
PENINSULA ONTO THE EASTERN SHORE OVERNIGHT...DECREASING TO ~20
ACROSS SW ZONES (WHERE DRY CONDITIONS MAY PREVAIL). CANNOT
COMPLETELY RULE OUT AN ELEVATED TSTM OR TWO (GIVEN STEEP H5 TO H7
LAPSE RATES OF 6.5 TO 7C)...BUT WILL PRECLUDE FROM FORECAST ATTM
GIVEN FAIRLY STABLE LOW LEVELS. LOWS TONIGHT IN THE MID 40S...TO
LOW/MID 50S AT THE COAST.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH FRIDAY/...
CLOSED LOW SLOWLY MOVES EAST AND OFFSHORE WED. AFTER A BRIEF
INCREASE IN DEEP MOISTURE OVERNIGHT...FORECAST SOUNDINGS BECOME
FAIRLY DRY ALOFT OVER INLAND SECTIONS AS THE TROUGH/SFC REFLECTION
SWING FARTHER OFFSHORE...HOWEVER A FAIRLY SHARP MOISTURE GRADIENT
PROGGED ALONG THE COAST. THE ERN SHORE IN PARTICULAR APPEARS TO BE
SET FOR A CLOUDY/COOL DAY WITH SHOWERS LIKELY. WILL THEREFORE KEEP
CHC POPS (25-50%) LIMITED TO FAR EASTERN VA...WITH LIKELY 60-70%
POPS ON THE EASTERN SHORE. COULD END UP BEING DRY OVER FAR W/SW
ZONES. QPF AMOUNTS TONIGHT/WED WILL AVG 0.25-0.75" ON THE ERN
SHORE...GENLY ONLY AROUND .10" OR LESS ELSEWHERE. FAVOR COOLER END
OF GUIDANCE FOR HIGHS WED...MID 60S SW TO AROUND 60/LOWER 60S NE.
OTHER FEATURE TO NOTE WILL BE THE INCREASING NW WINDS BY AFTN AS
THE SFC LOW INTENSIFIES FAIRLY RAPIDLY OFF THE COAST. GUSTS TO
25-35 MPH WILL BE POSSIBLE BY LATER AFTN/EVENING (ESPECIALLY NEAR
THE COAST).

THE CLOSED LOW MOVES FARTHER NE WED NIGHT INTO THU...LOCATING OFF
THE NEW ENGLAND COAST BY 00Z FRIDAY. ANY LEFTOVER SHOWER CHANCES
BY THEN WILL BE LIMITED TO THE EASTERN SHORE (20%). DECREASING
CLOUDS ARE ALSO EXPECTED ACROSS INTERIOR VA. LOWS WED NIGHT IN THE
LOW 40S TO LOW 50S. COOL AGAIN THU WITH HIGHS GENERALLY 60-65.
PRESSURE GRADIENT WILL REMAIN TIGHT IN BETWEEN SUB 1000 MB SFC LOW
OFF LONG ISLAND AND 1020 MB SFC HIGH OVER THE OH/TN VALLEY. EXPECT
BREEZY TO WINDY CONDITIONS WITH GUSTS TO 35 MPH ACRS THE ERN
SHORE...15-25 MPH ELSEWHERE.

LOW PRESSURE MOVES FARTHER NE AND AWAY FROM THE LOCAL AREA ON
FRIDAY ALLOWING FOR SUNSHINE...DIMINISHING WINDS...AND MILDER
TEMPS. HIGH FRIDAY IN THE MID TO UPR 60S.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
LOW PRESSURE LIFTS WELL TO THE NE FRIDAY NIGHT AND SATURDAY AS
UPPER RIDGING EXPANDS EASTWARD FROM THE CENTRAL US. A WEAK TROUGH
CLIPS THE NRN MID-ATLANTIC SATURDAY NIGHT AND QUICKLY MOVES OFF THE
COAST SUNDAY. A HIGH AMPLITUDE MID/UPPER LEVEL RIDGE BUILDS OVER THE
ERN US MONDAY AND TUESDAY...WITH THE AXIS SHIFTING OFFSHORE BY
MIDWEEK. GIVEN THIS...DRY CONDITIONS WILL PREVAIL THROUGH THE MEDIUM
RANGE PERIOD. HIGH TEMPERATURES SHOULD AVERAGE IN THE UPPER 60S TO
AROUND 70 SATURDAY AND SUNDAY...AND TREND UPWARD INTO THE LOW/MID BY
MONDAY AND TUESDAY (PERHAPS WARMER TUESDAY). LOWS SHOULD AVERAGE
FROM THE LOW/MID 40S NW...TO THE LOW/MID 50S FOR SE COASTAL
LOCATIONS.

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
EXPECT CLOUDS TO CONTINUE TO INCREASE THROUGH THE EVENING AND
OVERNIGHT WITH THE APPROACH OF A WEAK COLD FRONT. BEHIND THE
FRONT...STRONGER UPPER LEVEL SUPPORT WILL HELP A COOLER AIRMASS DIVE
INTO THE AREA. DRIZZLE ALONG WITH RAIN SHOWERS WILL BE LIKELY ACROSS
THE AREA AS THE UPPER WAVE MOVES THROUGH. EXPECT MVFR/IFR CEILINGS
TO DEVELOP OVERNIGHT AND LAST THROUGH NOON ON WED. WINDS WILL SHIFT
TO THE NW AFTER FRONTAL PASSAGE AND WILL INCREASE IN STRENGTH WED
AFTN AS THE PRESSURE GRADIENT INCREASES BEHIND THE STRENGTHENING
SURFACE LOW TO THE EAST AND HIGH PRESSURE BUILDING IN FROM THE NW.
WINDS WILL GUST TO NEAR 20KT DURING THE AFTERNOON.

DRIER AIR WILL FILTER INTO THE AREA WED EVENING AS THE SURFACE HIGH
NUDGES FARTHER EAST. EXPECT DRY CONDITIONS ACROSS MOST OF THE FA THU
AND FRI WITH STRONGER NW WINDS ALONG THE COAST.

&&

.MARINE...
A COLD FRONT WILL SLOWLY CROSS THE MID ATLANTIC COAST TONIGHT...WITH
LOW PRESSURE INTENSIFYING OFF THE NORTHEAST COAST WEDNESDAY
AFTERNOON INTO WEDNESDAY NIGHT. THIS WILL PRODUCE SCA
CONDITIONS...BEGINNING WEDNESDAY AFTERNOON FOR MOST OF THE AREA AND
CONTINUING INTO AT LEAST THURSDAY. THE CURRENT FORECAST WIND IS
GENERALLY 20-25KT...WITH GUSTS TO AROUND 30KT FOR MOST OF THE MARINE
AREA. THERE IS A POTENTIAL FOR LOW-END GALE CONDITIONS LATE
WEDNESDAY AFTERNOON INTO WEDNESDAY EVENING PRIMARILY SUPPORTED BY
THE 21/12Z NAM. AT THIS TIME THE CURRENT SCA WAS MAINTAINED GIVEN
THE POTENTIAL FOR ONLY MARGINAL GALE CONDITIONS...WITH AN ONSET
GENERALLY AT OR BEYOND 24HR FROM 4PM TUESDAY. THIS SYSTEM IS
EXPECTED TO STALL OFFSHORE THURSDAY NIGHT AND FRIDAY WITH SCA
CONDITIONS LIKELY CONTINUING...ESPECIALLY FOR THE OCEAN. WITH THE
FLOW BEING OFFSHORE FROM THE NW...SEAS WOULD TEND TO STAY CAPPED AT
5-7 FT AND TIDAL FLOODING IS NOT EXPECTED. N/NW FLOW IS EXPECTED TO
CONTINUE INTO NEXT WEEKEND WITH SPEEDS DIMINISHING TO 10-15KT AND
SEAS SUBSIDING.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 1 PM WEDNESDAY TO 5 PM EDT THURSDAY
     FOR ANZ630>638-650-652-654-656-658.

&&

$$
SYNOPSIS...JDM
NEAR TERM...JDM
SHORT TERM...JDM/LKB
LONG TERM...AJZ
AVIATION...DAP
MARINE...AJZ





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