Area Forecast Discussion
Issued by NWS Wakefield, VA

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
000
FXUS61 KAKQ 192002
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
402 PM EDT FRI SEP 19 2014

.SYNOPSIS...
HIGH PRESSURE OVER NEW ENGLAND WILL SLOWLY EXIT THE REGION ON SATURDAY.
LOW PRESSURE DEVELOPS OFF THE SOUTH CAROLINA COAST ON SATURDAY AND
LIFTS UP THE ATLANTIC SEABOARD ON SUNDAY. A QUICK MOVING COLD
FRONT SWEEPS THROUGH THE REGION ON SUNDAY NIGHT WITH HIGH PRESSURE
RETURNING FOR MOST OF NEXT WEEK WITH COOLER AND DRIER CONDITIONS.

&&

.NEAR TERM /THROUGH SATURDAY/...
HIGH PRESSURE CENTERED OVER NEW ENGLAND IS IN CONTROL OF THE
REGIONS WEATHER THIS EVENING...BUT MOISTURE HAS BEEN TRAPPED UNDER
THE RIDGE TODAY AND WITH THE LOW LEVEL EASTERLY FLOW...THE CLOUDS
HAVE BEEN SLOW TO CLEAR. BUT THIS AFTERNOON...HAVE SEEN MUCH OF
THE CLOUDS OVER VA/ERN NC BREAK UP. OVER LWR MD ERN SHORE...THE
MOISTURE HAS STREAMED IN OFF THE ATLANTIC AND PROVIDE A PERIOD OF
BROKEN CLOUDS. THE MODELS INDICATE THAT THIS MOISTURE WILL
CONTINUE TO MOVE WWD INTO CENTRAL MD AND ALLOW FOR SOME CLEARING
THIS EVENING. OVER VA...THE MOISTURE WILL CONTINUE TO MOVE THROUGH
THE PIEDMONT AND ALLOW FOR CLEARING THIS EVENING. WITH THE GENERAL
LIGHT WINDS AND CLEAR SKY TONIGHT RADIATIVE COOLING SHOULD BE GOOD
ESPECIALLY IN THE WEST SO HAVE GONE A LITTLE COOLER THERE TOWARD
THE MAV NUMBERS.

ON SATURDAY...THE SFC HIGH TO THE NE RETREATS AND A DEVELOPING LOW
ALONG THE SC COAST WILL ORGANIZE. THIS WILL HELP TO INCREASE THE
EASTERLY FLOW AND LOW LEVEL MOISTURE. SO HAVE INCREASED CLOUDS AND
KEPT A CHANCE FOR SOME LIGHT SHOWERS ALONG THE COAST. IN
LAND...THE SFC RIDGE SHOULD KEEP THE CLOUDS AT BAY FOR AREAS WEST
OF A LINE FROM XSA/AKQ/FKN/ASJ. THE CLOUD WILL BE THICKER ACROSS
ERN NC AS THE UPPER LEVEL CIRRUS WILL ALSO BE THICKENING DURING
THE DAY. FOR TEMPERATURES...HAVE WARMED VALUES INLAND WITH THE
SUNSHINE EXPECTED...ALONG THE COAST HOWEVER...DID TRIM THE HIGHS
BACK A LITTLE UNDER THE GUIDANCE DUE TO HIGH CLOUDS AND ONSHORE FLOW.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
THE MODELS ARE IN GOOD AGREEMENT IN THE MID RANGE PERIOD. THE
CLOSE LOW ALOFT THAT IS ASSOCIATED WITH THE COASTAL LOW IS
FORECAST TO OPEN UP AND BEGIN TO SHEAR OUT AS A STRONGER TROUGH
DIGS THROUGH THE OHIO VALLEY AND GREAT LAKE STATES. THIS WILL KEEP
THE LOW FROM BRINGING MORE MOISTURE AND PCPN INLAND...WITH THE
BULK OF THE PRECIPITATION REMAINING ON THE EASTERN SIDE OF THE
STORM OFF SHORE. SO HAVE KEPT SLIGHT CHANCE TO CHANCE POPS ALONG
THE COAST SAT NIGHT INTO EARLY SUNDAY BEFORE REMOVING THE CHANCE
OF RAIN AFTER NOON SUNDAY. TEMPERATURES WILL RECOVER SOME DURING
THE AFTERNOON INTO THE LOW TO MID 80S.

WEAK HIGH PRESSURE PROVIDES ANOTHER DRY AND WARM DAY AWAY FROM
THE COAST ON SUNDAY IN ADVANCE OF THE COLD FRONT. WITH 850 TEMPS
CLIMBING TO AROUND 17C SHOULD SEE TEMPERATURES IN THE MID TO UPPER
80S AWAY FROM THE COAST.

THE COLD FRONT FRONT WILL APPROACH FROM THE NORTHWEST SUNDAY
EVENING. THE MODELS SHOW A VERY NARROW BAND OF MOISTURE WITH THE
FRONT AND THE STRONGEST DYNAMICS SWEEP ACROSS PA. WITH THE BEST
FORCING TO THE NORTH AND THE LIMITED MOISTURE...HAVE KEPT POPS IN
THE SLIGHT CHANCE RANGE EXCEPT IN THE NRN DELMARVA AND ALONG THE
SE COAST WHERE MOISTURE MAY BE A LITTLE MORE ABUNDANT. ONCE THE
FRONT CLEARS THE AREA BY MID MORNING MONDAY...HIGH PRESSURE BUILDS
INTO THE AREA AND MUCH DRIER AIR ARRIVES AND TEMPERATURES SHOULD
REMAIN IN THE MID 70S TO AROUND 80 DEGREES.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
A REINFORCING COLD FRONT WILL USHER IN BELOW NORMAL TEMPS THROUGH
THE EXTENDED AS COOL CANADIAN HIGH PRESSURE BUILDS OVER THE THE NE.

MEDIUM RANGE GUIDANCE IN FAIRLY GOOD AGREEMENT OVER THE ERN CONUS
WITH THE EVOLVING AMPLIFIED UPPER AIR PATTERN. AMPLIFIED PATTERN
WILL FEATURE A LONGWAVE TROUGH OVER THE ERN CONUS TO BEGIN THE
PERIOD. AN ASSOCIATED SECONDARY/REINFORCING COLD FRONT WILL SWEEP
THROUGH THE REGION MONDAY MORNING. MOISTURE WILL BE RATHER LIMITED
ALONG THE FRONT (PWATS ~1.5 INCHES)...BUT HEIGHT FALLS AND INCREASING
WINDS ALOFT (JET STREAK ROUNDING THE BASE OF THE UPPER TROUGH) WILL
PROVIDE FORCING FOR ASCENT OVER THE REGION. SHOULD BE ENOUGH FOR
SLIGHT CHANCE/ISOLATED POPS...WITH THE BEST COVERAGE OVER THE NRN
LOCAL AREA. THE BIGGER HEADLINE WITH THE FRONT WILL BE THE DRY AIR
AND COLD AIR ADVECTION POST FRONTAL AS HIGH PRESSURE BUILDS IN
FROM THE W-NW. MON WILL BE A TRANSITION DAY AS THE COOLEST/DRIEST
AIR LAGS BEHIND THE FRONT. REINFORCING SHORTWAVE CROSSES THE GREAT
LAKES-NE STATES TUES AS THE TROUGH AXIS PUSHES OFF THE ERN
SEABOARD. MEANWHILE...MID-LEVEL RIDGE WILL PROGRESS EWD OVER THE
CNTRL PLAINS AND INTO THE ERN CONUS TUES- WEDS. COOL CANADIAN HIGH
PRESSURE PROGGED TO BUILD OVER NEW ENGLAND WEDS. UPPER/SFC HIGH
PRESSURE REMAINS OVER THE REGION THURS. THE RESULT WILL BE
CONTINUED DRY CONDITIONS AND BELOW NORMAL TEMPS.

HIGHS WILL BE BELOW AVG THRU THE PERIOD...WITH TUES AND WEDS BEING
THE COLDEST DAYS AT NEARLY -1 STD DEV (LOW-MID 70S). WENT A LITTLE
ABOVE WPC GUIDANCE AS LOW LEVEL THICKNESSES YIELD SLIGHTLY WARMER
TEMPS UNDER MOSTLY SUNNY SKIES. LOWS GENERALLY IN THE LOW-MID 50S
INLAND TO LOW 60S NEAR THE COAST. FEW LOCALES IN THE PIEDMONT MAY
DROP INTO THE UPPER 40S AT NIGHT.

&&

.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
STRONG HIGH PRESSURE OVER NEW ENGLAND WITH NE-E WINDS OVER THE
CWA. VFR CONDS GENERALLY PREVAIL OVER THE REGION BUT WITH MID AND
LOW CLOUDS DUE TO PLENTY OF MOISTURE OFF THE ATLANTIC. WINDS ARE
MOSTLY 10 KT OR LESS BUT SOME GUSTY CONDS PERSIST CLOSE TO THE
COAST. A FEW VERY LIGHT SHOWERS OVER THE REGION DUE TO A WEAK SFC
TROF OR UPSLOPE IN THE PIEDMONT. NO SIG WX EXPECTED THRU THE
PERIOD. CLOUDS WILL GRADUALLY THIN OUT THIS AFTN/EVENING FROM RIC
EAST...WHILE MORE CLOUDINESS AND PSBL MVFR CONDS EXPECTED WEST OF
RIC.


OUTLOOK...MAINLY VFR AND DRY WEATHER ARE EXPECTED TO CONTINUE INTO
SUN. AN AREA OF LOW PRES MOVG UP THE EAST COAST MAY BRING
INCREASING CLOUDS AND CHC OF RAIN FOR NE NC AND SE VA LATE SUN
INTO MON.

&&

.MARINE...
NELY TO ELY FLOW THIS AFTERNOON IS RESULTING FROM HIGH PRESSURE
OVER NEW ENGLAND. GRADIENT HAS TIGHTENED A LITTLE THIS AFTERNOON
ALLOWING FOR GUSTS OF 12-19KT ESPECIALLY AT THE MOUTH OF THE BAY AND
OVER THE COASTAL WATERS. SEAS HAVE BEEN SLOW TO BUILD TODAY WITH
3 TO 4 FT SEAS OFF DUCK NC AND OFF OCEAN CITY. SEAS OFF SOUTHEAST
VA REMAIN AROUND 3 FT. SEAS SOUTH OF DUCK HAVE BEEN BUILDING TO 5
TO 6 FT AND SEAS ARE STILL EXPECTED TO BUILD TO MARGINAL SCA LATER
TONIGHT INTO SAT MORNING. SCA HEADLINES GO INTO EFFECT FOR ALL THE
COASTAL WATERS AT 1 AM.

HIGH PRESSURE PUSHES OFF THE NEW ENGLAND COAST SAT AS LOW
PRESSURE DEVELOPS ALONG A STALLED BOUNDARY OFF THE NC COAST. THE
LOW WILL SLOWLY LIFT ALONG THE BOUNDARY SATURDAY AND SUNDAY
PASSING WELL OFF THE VA COAST LATE SUNDAY. THIS WILL RESULT IN A
NELY TO NLY FLOW OVER THE COASTAL WATERS AND BAY FOR MOST OF THE
WEEKEND. SCA CONDITIONS FOR WIND SPEEDS ARE NOT ANTICIPATED ATTM
BASED ON THE GRADIENT WIND FORECAST. HOWEVER...SEAS WILL LIKELY
REMAIN ELEVATED (4-5 FT) THRU SAT...BEFORE SUBSIDING ON SUNDAY
AHEAD OF A COLD FRONT WITH WINDS TURNING OFFSHORE. SCA HAVE BEEN
EXTENDED INTO SAT NIGHT AND MAY NEED TO EXTENDED INTO SUNDAY FOR
SEAS.

SFC LOW LIFTS NE OFF THE COAST LATE SUNDAY WITH A COLD FRONT
FORECAST TO CROSS THE REGION MONDAY MORNING. SEAS MAY BRIEFLY
BUILD TO 5 FT AGAIN SUNDAY NIGHT INTO EARLY MONDAY. NW WINDS 10-15 KT ON
MONDAY WILL GRADUALLY BECOME N-NE ON TUESDAY. HIGH PRESSURE WILL
LOCK IN ACROSS NEW ENGLAND AND EXTEND INTO THE MID ATLANTIC FOR A
GOOD PORTION OF NEXT WEEK. THIS WILL RESULT IN A PROLONGED PERIOD
OF NELY FLOW ACROSS THE REGION.

&&

.HYDROLOGY...
LATEST DROUGHT INFO SHOWING AN AREA OF ABNORMALLY DRY CNDTNS ACROSS
PORTIONS OF VA. THIS INCLUDES AREAS N OF I 64 & RT 360 (INCLUDING
THE RIC METRO AREA) IN AKQ FA. OTHER THAN SCT CONVECTION WITH THE
FRNT SUN EVE...XTNDD MODELS DO NOT SHOW MUCH IN THE WAY OF RELIEF
FOR THE NEXT WEEK.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
     MDZ025.
NC...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
     NCZ102.
VA...MODERATE RIP CURRENT RISK UNTIL 8 PM EDT THIS EVENING FOR
     VAZ098>100.
MARINE...SMALL CRAFT ADVISORY FROM 1 AM TO 7 PM EDT SATURDAY FOR ANZ650-
     652-654-656.
     SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 7 PM EDT
     SATURDAY FOR ANZ658.

&&

$$
SYNOPSIS...ESS
NEAR TERM...ESS
SHORT TERM...ESS
LONG TERM...JAO
AVIATION...JEF
MARINE...JAO
HYDROLOGY...






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