FXUS61 KAKQ 050911
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
411 AM EST SUN FEB 5 2012

.SYNOPSIS...
LOW PRESSURE MOVES EASTWARD ACROSS THE CAROLINAS THIS
MORNING...THEN OFF THE COAST BY THIS AFTERNOON. WEAK HIGH PRESSURE
BUILDS INTO THE AREA FROM THE NORTH LATE TODAY INTO MONDAY. LOW
PRESSURE MOVES NORTHEAST ALONG THE CAROLINA COAST MONDAY NIGHT.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
LATEST MSAS ANALYSIS SHOWS A SFC LOW OVER NW NORTH CAROLINA WITH A
COLD FRONT STRETCHING EASTWARD FROM THIS LOW INTO EAST-CENTRAL NC.
MEANWHILE...SFC HIGH PRESSURE OVER NEW ENGLAND CONTINUES TO SETTLE
SOUTHWARD INTO THE MID-ATLANTIC REGION NORTH OF THE COLD FRONT.
LATEST RADAR IMAGES SHOW BULK OF RAIN JUST EAST OF THE SFC LOW
MOVING EAST ALONG THE COLD FRONT ACROSS CENTRAL NC. THIS RAIN WILL
CONTINUE TO MOVE EASTWARD THROUGH THE MORNING HOURS AS THE SFC LOW
TRACKS EASTWARD IN RESPONSE TO A SOUTHEASTWARD MOVING SHORTWAVE
TRACKING SE THROUGH THE EASTERN GREAT LAKES AND OHIO VALLEY. AS
SUCH...WILL MAINTAIN CATEGORICAL POPS ACROSS SOUTHERN VIRGINIA AND
NE NC THROUGH MIDDAY. FARTHER NORTH (ESPECIALLY FROM KRIC
NORTHWARD) EXPECTING AREAS OF LIGHT RAIN AND DRIZZLE. ONCE THE SFC
LOW MOVES OFFSHORE AROUND MIDDAY...RAIN/DRIZZLE WILL GRADUALLY TAPER
OFF FROM NORTH TO SOUTH THROUGH THE AFTERNOON. ALTHOUGH P-TYPE
WILL NOT BE AN ISSUE TODAY...IN-SITU CAD/WEDGE SETUP WILL MAKE
FOR A RAW/CHILLY DAY WITH HIGH TEMPS NO BETTER THAN THE MID/UPR
40S...TO LOW 50S ACROSS COASTAL NE NC.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
LATEST MODELS KEEP ENOUGH MOISTURE LINGERING ACROSS NE NC FOR
SLIGHT CHC POPS THROUGH SUNSET. OTHERWISE...CROSS-SECTIONS SHOW A
DRYING COLUMN WITH DECREASING CLOUDINESS TONIGHT AS HIGH PRESSURE
MOVES OVERHEAD. LOWS 30-35...EXCEPT UPR 30S ACROSS SERN COASTAL
AREAS.

HIGH PRESSURE BEGINS THE DAY OVER THE REGION MONDAY...BUT A S/W
TROF MOVES ACROSS THE AREA MONDAY NIGHT THAT ACTUALLY DEVELOPS A
SFC LOW OFF THE CAROLINA COAST. THE MODELS DIFFER ON JUST HOW FAR
WEST/NORTH ANY MOISTURE GETS. GIVEN THE UNCERTAINTY...WILL HAVE
SLIGHT CHC RAIN ACROSS THE VA TIDEWATER AND INTERIOR NE NC MONDAY
AFTERNOON/NIGHT...AND A CHC OF RAIN ACROSS COASTAL NE NC. THIS
SYSTEM PULLS AWAY BY DAYBREAK TUESDAY. HIGHS MONDAY 50-55. LOWS
MONDAY NIGHT FROM THE LOW 30S NW TO THE LOW/MID 40S SERN COASTAL
AREAS.

DRY TUESDAY AS WEAK HIGH PRESSURE MOVES OVER THE AREA AHEAD OF NEXT
COLD FRONT APPROACHING FROM THE NW. HIGHS IN THE 50S..EXCEPT MAYBE
ONLY UPR 40S ON PARTS OF THE EASTERN SHORE.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
LATEST SUITE OF MODELS ARE NOW IN BETTER AGREEMENT W/ THE EXTENDED
TIMEFRAME. THEY ALL SHOW THE DEVELOPMENT OF A +PNA PATTERN...WITH
RIDGING OVER THE WESTERN CONUS EXTENDING WELL UP INTO NW
CANADA. THIS WILL DRIVE COLD AIR THAT HAD BEEN IN PLACE FOR MUCH
OF THE WINTER SEASON OVER ALASKA/NW CANADA INTO ERN CANADA.
HOWEVER...WITHOUT DOWNSTREAM RIDGING TOO FAR OFF TO THE EAST (GENLY
STAYING E OF GREENLAND)...BULK OF THE COLD AIR WILL REMAIN NORTH
OF THE MID ATLC THROUGH THE EXTENDED PERIOD (I.E. NO -NAO). THIS
WOULD SUPPORT ONLY A MODEST COOL-DOWN GOING INTO NEXT WEEKEND.

WED WILL FEATURE HIGH PRESSURE TO OUR NORTH...EXTENDING FROM THE
GREAT LAKES EAST INTO NY STATE...GRADUALLY MOVING OFF INTO NEW
ENGLAND WED NIGHT/THU...NOSING SOUTHWARD INTO THE MID ATLC. WITH
WEAK MID LEVEL SHORTWAVE ENERGY APPROACHING FROM THE WSW AND
BRUSHING THE CWA LATE WED/WED NIGHT...WILL CARRY 20-30% CHANCE
FOR -RA ALL ZONES (HIGHEST NORTH). STAYED ON COOL SIDE OF GUIDANCE
GIVEN THE SYNOPTIC SETUP FOR AT LEAST WEAK CAD...HIGHS MAINLY
45-50 NW...TO THE MID 50S SE. AFTER THAT...KEPT THE REST OF PERIOD
DRY AS POLAR VORTEX AND MAIN UPR TROUGH REMAIN TO OUR NORTH. HIGHS
STAY NEAR OR SLIGHTLY ABOVE AVG THU-FRI (HIGHS IN UPR 40S TO MID
50S)...COOLING A FEW DEGREES BY SAT 40S TO LOWER 50S FAR SE).

&&

.AVIATION /09Z SUNDAY THROUGH THURSDAY/...
WIDESPREAD IFR CONDITIONS SHOULD CONTINUE OVERNIGHT WITH PERIODS
OF LIGHT RAIN AND DRIZZLE CONTINUING MAINLY SOUTH OF RIC. A SLOW
IMPROVEMENT IS EXPECTED N-S BEGINNING EARLY THIS MORNING. IFR
CONDITIONS SHOULD END FIRST AT SBY AROUND 10Z...AND LINGER TOWARD
MIDDAY FOR ORF/ECG. BY AFTERNOON CEILINGS SHOULD CONTINUE TO
LIFT...BUT REMAIN MVFR FOR SE LOCATIONS. HIGH PRESSURE BUILDS IN
BY TONIGHT WITH CLEARING NORTH AND SCT MID-CLOUDS SOUTH. A LIGHT
NNE WIND SHOULD PREVAIL THROUGH EARLY MORNING AND INCREASE TO
8-12KT DURING THE DAY...BEFORE BECOMING LIGHT TONIGHT.

A QUICK MOVING LOW PRESSURE SYSTEM OFF THE COAST MAY BRING A
PERIOD OF RAIN AND LOWER CEILINGS TO ORF/ECG MONDAY NIGHT. ANOTHER
SYSTEM PASSES NORTH OF THE REGION AROUND WEDNESDAY/WEDNESDAY
NIGHT. HOWEVER...DRY AND VFR CONDITIONS SHOULD PREVAIL MOST OF THE
WEEK.

&&

.MARINE...
LOW PRESSURE CONTINUES TO TRACK EASTWARD ACROSS NC EARLY THIS
MORNING AND WILL DEEPEN AND MOVE OFF THE COAST TODAY. THE PRESSURE
GRADIENT BRIEFLY TIGHTENS IN THE WAKE OF THE LOW. THE NAM/WRF BASED
GUIDANCE REMAINS STRONGEST WITH THE WIND...BUT STILL MARGINAL SCA
(15 TO 20KT) FOR THE BAY AND SOUND. THE CURRENT SCA FLAGS WILL
REMAIN AS IS. FOR THE OCEAN...CONFIDENCE IS HIGHER AS A NNE WIND
SHOULD PUSH SEAS TO 5 FT...AND AS WITH THE BAY AND SOUND THE SCA
FLAGS FOR THE OCEAN WILL REMAIN AS IS. THE ONLY EXCEPTION IS ALL SCA
FLAGS WILL GO INTO EFFECT WITH THIS FORECAST ISSUANCE GIVEN THAT IT
IS WELL WITHIN 12 HOURS OF THE ONSET.

HIGH PRESSURE BUILDS IN FROM THE NORTH TONIGHT...AND WIND AND SEAS
SHOULD STEADILY DIMINISH/SUBSIDE. A MID-LEVEL TROUGH APPROACHES FROM
THE WEST MONDAY AND TRIGGERS LOW PRESSURE DEVELOPMENT OFF THE SC
COAST. THIS LOW IS EXPECTED TO MOVE NE OFF THE OUTER BANKS MONDAY
NIGHT. A GFS-BASED FORECAST WAS FOLLOWED FOR THIS SYSTEM PER PMDHMD.
CONDITIONS ARE LIKELY TO REMAIN SUB-SCA...ALTHOUGH THERE IS A
POSSIBILITY THE ENOUGH NORTHERLY FLOW COULD PUSH SEAS TO 5 FT OFF
THE CURRITUCK OUTER BANKS LATE MONDAY NIGHT AND EARLY TUESDAY
MORNING. STRONG HIGH PRESSURE BUILDS NORTH OF THE REGION THROUGH
MIDWEEK...BUT WIND SPEEDS ARE EXPECTED TO REMAIN AOB 15KT AT THIS
TIME.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST THIS EVENING FOR ANZ631-
632-634-650-652-654-656.
SMALL CRAFT ADVISORY UNTIL 1 AM EST MONDAY FOR ANZ633-658.

&&

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

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