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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 271201
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
701 AM EST TUE JAN 27 2015

.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY AS IT TRACKS
NORTH NORTHEAST OFF THE NEW ENGLAND COAST THROUGH TONIGHT.
MEANWHILE...HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC
THROUGH MIDWEEK. A COLD FRONT WILL CROSS THE AREA THURSDAY
NIGHT...FOLLOWED BY HIGH PRESSURE THROUGH SATURDAY.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
QUICK UPDATE TO CLEAR MARYLAND EASTERN SHORE COUNTIES FROM WITNER
WX ADVISORY BASED ON RADAR TRENDS. GIVEN LATEST REPORTS AND
TRAFFIC CAMS IN METRO RIC/ORF AREAS, WILL CONTINUE THEM ELSWEHERE.

PREVIOUS DISCUSSION...

EARLY MORNING RADAR MOSAIC SHOWING NARROW BAND OF PCPN DROPPING
SOUTH FROM CENTRAL PA SOUTH INTO EASTERN/CENTRAL VA. VSBY AVGG
2-4SM IN SN, AND WE`VE RECEIVED QUITE A FEW REPORTS ~1 AND A FEW
IN THE 1 1/2 TO 2" ALONG THE NORTHERN NECK INTO THE PENINSULA.
TRAFFIC CAMS SHOWING AT LEAST A COATING INTO THE TIDEWATER AREA
(CONFIRMED BY LOCAL COOPERATIVE OBSERVER). WE WILL BE MAINTAINING
WINTER HEADLINES FOR A LITTLE LONGER, WITH THIS BAND OF SNSH WELL
HANDLED BY THE HRRR EARLY THIS MORNING. NOT EXPECTING ANY LOCALES
IN NORFOLK OR RICHMOND METRO AREAS WILL RECEIVE ANY MORE THAN AN
INCH...BUT WITH THE HEADLINE ALREADY IN PLACE AND THE POTENTIAL
FOR SNOW TO CAUSE SOME IMPACTS DURING THE MORNING COMMUTE...DON`T
FEEL DROPPING THE HEADLINES IS PRUDENT ATTM. WL REVISIT HEADLINES
AT 7AM UPDATE. DO EXPECT DAY CREW WILL BE ABLE TO CLEAR HEADLINES
SHORTLY AFTER 14Z IF NOT SOONER.

HAVE BUMPED POPS UP IN TO CATEGORICAL RANGE FOR COASTAL NE NC, AND
GRADUALLY TAPERED THEM OFF ALONG THE EASTERN SHORE BY MID-LATE
MORNING. DROPPED POPS INTO NO HIGHER THAN 20% BUT HAVE KEPT
FLURRIES IN THE FORECAST FOR FAR WESTERN ZONES, AS ACCUMS NOT
ANTICIPATED.

INTENSIFYING SFC LOW WILL CONTINUE TO LIFT NE INTO NEW ENGLAND
THROUGH TONIGHT. ALL POPS DROP OFF BY EARLY AFTN, WITH STRONG CAA
BRINGING BREEZY/WINDY CONDITIONS (25-30MPH GUSTS ALONG THE
COAST/ERN SHORE), AND HOLDING HIGHS IN THE MID TO UPPER 30S (~40
IN THE PIEDMONT) UNDER A CLOUDY TO MOSTLY CLOUDY SKY.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED COASTAL LOW PULLS TOWARDS ATLANTIC
CANADA AS COLD SFC HIGH PRESSURE BUILDS IN FROM THE W. CLEARING
SKY AND GRADUALLY DIMINISHING NW WINDS WILL ALLOW EARLY MORNING
LOW TEMPS TO FALL INTO THE THE 20S FOR MOST, W/ WIND CHILLS IN THE
TEENS IN MOST LOCATIONS.

HIGH PRESSURE BUILDS OVER THE LOCAL AREA ON WEDNESDAY.
TEMPERATURES REMAIN COOL WITH SHALLOW MIXING AND A NNE WIND. HIGHS
ONLY RANGING FROM THE MID 30S OVER THE LWR ERN SHORE TO THE UPR
30S TO LWR 40S ELSEWHERE. DRY AGAIN FOR WED NIGHT WITH LOWS IN THE
20S TO NEAR 30 ALONG THE COAST.

RAIN CHCS INCREASE ACROSS THE AREA LATER THU/THU NGT AS NORTHERN
STREAM SHORTWAVE TROUGH TRACKS FROM THE UPPER MIDWEST ACROSS TO
THE GREAT LAKES, WITH THE ASSOCIATED SFC LOW PUSHING ACROSS THE
NORTHERN MID-ATLANTIC INTO NEW ENGLAND BY LATE THU NGT. DAY BEGINS
PARTLY CLOUDY WITH GRADUALLY INCREASING CLOUDS. BEST FORCING
REMAINS OFF TO THE NORTH, SO HAVE CAPPED POP AT NO HIGHER THAN 30%
FOR NOW. RAIN CHANCES DIMINISH THU NGT AS SFC COLD FRONT PUSHES
ACROSS THE AREA. FOR HIGHS, SW FLOW AHEAD OF THE FRONT WILL ALLOW
FOR A MODEST WARMUP WITH MAXIMA IN THE U30S ERN SHORE/NRN
NECK...LOWER TO MID 40S INLAND AND U40S FAR SOUTHERN ZONES.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. HIGH PRESSURE BUILDS IN FROM THE
WEST FRIDAY AND SATURDAY. ANOTHER COLD FRONT APPROACHES FROM THE
NW AND THEN MOVES ACROSS THE REGION LATE SUNDAY. EURO HAS A QUICK
MOVING FRONTAL WAVE MOVE ACROSS THE CAROLINAS LATE SUNDAY AND OUT
TO SEA MONDAY. THERE WILL BE A CHC FOR RAIN OR SNOW WITH THIS
SYSTEM BUT CONFIDENCE FOR SIGNIFICANT WINTER WEATHER IS LOW AT
THIS POINT.

HIGH TEMPERATURES ARE FORECAST IN THE UPR 30S AND 40S THURSDAY
LOWERING TO MOSTLY 30S TO AROUND 40 SATURDAY THROUGH MONDAY. LOWS
ARE EXPECTED TO RANGE THROUGH THE 30S FRIDAY MORNING AND MOSTLY 20S
SATURDAY THROUGH MONDAY MORNINGS.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 12Z...WITH EITHER LOW
MVFR OR IFR CONDITIONS THROUGHOUT. SOME VARIABILITY IS ANTICIPATED
IN CIGS/VSBYS THROUGH 15Z AND HAVE GONE WITH TEMPO IFR CONDITIONS
FOR MOST TAF SITES THROUGH 14-15Z. GUSTY N/NW WINDS TO AROUND 25
KT AT ORF/KECG...AROUND 20 KT ELSEWHERE.

CONDITIONS WILL GRADUALLY IMPROVE AFTER 15Z...WITH CIGS LIFTING
TO 1500-2500 FT THEREAFTER. WINDS SHIFT MORE TO THE NW AND REMAIN
GUSTY TO AROUND 20 KT.

OUTLOOK...VFR/DRY WEATHER IS EXPECTED TUE NIGHT THROUGH THU AFTN. A
WEAK SYSTEM MAY DROP CIGS AND VSBYS IN LIGHT RAIN THU NIGHT/EARLY
FRI.

&&

.MARINE...
UPDATE...DOWNGRADED THE GALE WARNING TO SCA FLAGS FOR NRN COASTAL
WATERS FROM FENWICK ISLAND TO PARRAMORE ISLAND. WIND GUSTS HAVE
STRUGGLED TO REACH 34KT OR GREATER AT SFC BUOYS. SCA FOR NRN WATERS
WILL NOW BE IN EFFECT THROUGH MIDNIGHT WEDNESDAY NIGHT...AFTER WHICH
WINDS AND PRIMARILY SEAS WILL DROP BELOW SCA THRESHOLDS.

PREVIOUS DISCUSSION...STRONG COASTAL LOW IS LOCATED ABOUT 225 MILES
EAST OF ATLANTIC CITY NJ AS OF 4 AM. THE SFC PRESSURE GRADIENT
REMAINS VERY TIGHT...ESPECIALLY ALONG THE ATLANTIC COAST. THE ADDED
CAA AND DIURNAL EFFECTS ARE CAUSING N-NW WINDS TO EXPERIENCE A BRIEF
SURGE IN SPEEDS. SEAS HAVE QUICKLY RISEN TO 8-12FT IN SRN COASTAL
WATERS AS WELL. THE SURGE IN WINDS/SEAS IS EXPECTED TO BE BRIEF...
LASTING THROUGH SUNRISE...AFTER WHICH WINDS WILL DIMINISH SLIGHTLY
AND SEAS WILL SLOWLY SUBSIDE THROUGH THIS AFTN TO 5-7FT SRN
WATERS/6-10FT NRN WATERS...AS THE LOW TRACKS NE AND AWAY FROM THE
MID ATLANTIC COAST. FOR TONIGHT...THE STRONG LOW TRACKS TWD THE
CANADIAN MARITIMES AS HIGH PRESSURE BUILDS OVER THE OHIO VALLEY...
KEEPING A TIGHT PRESSURE GRADIENT OVER THE WATERS. PRESSURE RISES
AROUND 3MB THIS EVENING (OCCURRING BTWN 21Z TODAY AND 06Z TONIGHT)...
INDICATE THAT ANOTHER NWLY SURGE WITH GUSTS AROUND 30KT IS POSSIBLE
THIS EVENING FOR THE BAY/OCEAN AS CAA AND WRAPAROUND SHORTWAVE
ENERGY TRAVERSE THE WATERS.

HIGH PRESSURE SLOWLY BUILDS INTO THE MID ATLANTIC REGION ON WED.
CONTINUED CAA WILL KEEP NW WINDS ELEVATED WITHIN SCA THRESHOLDS
OVER ALL WATERS THROUGH THE DAY. HOWEVER...SEAS WILL SHOW A MARKED
DECREASE TO 4-5FT BY WED AFTN. ONLY CHANGE MADE TO SCA FLAGS WAS
TO EXTEND CHES BAY AND SRN COASTAL WATERS THROUGH 10 PM WED
EVENING BEFORE WINDS/SEAS FALL BELOW SCA THRESHOLDS. SEAS CONTINUE
TO SUBSIDE THRU WED EVENING AS HIGH PRESSURE SLIDES OVER THE
WATERS. A CLIPPER SYSTEM APPROACHING THE REGION ON THU WILL SHUNT
THE HIGH OVER THE SE COAST. THE COLD FRONT ASSOCIATED WITH THE
CLIPPER IS THEN EXPECTED TO CROSS THE WATERS THU NIGHT...FOLLOWED
BY POTENTIALLY SOLID SCA CONDITIONS FRI/FRI NIGHT.

&&

.TIDES/COASTAL FLOODING...
COASTAL FLOOD ADVISORY FOR OCEAN CITY HAS BEEN CANCELLED...FELL
SHORT OF MINOR FLOODING THRESHOLDS AS WINDS SHIFTED FASTER THAN
EXPECTED FROM ONSHORE E/NE MON AFTN TO OFFSHORE N/NW. DEPARTURES
HAVE BEEN BETWEEN 1.5 AND 2 FT ABOVE ASTRONOMICAL TIDE. MDL
GUIDANCE SHOWS THE UPCOMING TIDE THIS AFTN REACHING ABOVE 4 FT
MLLW...BUT THIS APPEARS WELL OVERDONE GIVEN THE N/NW WIND
DIRECTION AND CURRENT OBS AND TRENDS. NAM- BASED CBOFS GUIDANCE IS
RUNNING ABOUT 2 FT HIGHER THAN REALITY...BUT IN TERMS OF TREND
SHOWS THE TIDE THIS AFTN TO BE SLIGHTLY LOWER THAN THE HIGH TIDE
EARLIER THIS MORNING THAT ONLY PEAKED AT 3.7 FT MLLW. HAVE ISSUED
A COASTAL FLOOD STATEMENT RATHER THAN AN ADVISORY AT THIS POINT
GIVEN THE UNFAVORABLE OFFSHORE WIND FLOW.

ACRS THE LOWER BAY DEPARTURES ARE ALSO RUNNING AS HIGH AS 1.5 TO 2
FEET...BUT THIS STILL LEADS TO TIDES FALLING AT LEAST 0.5 FT SHY
OF MINOR FLOODING THIS AFTN. DEPARTURES WILL FALL TONIGHT INTO WED
WITH NO FLOODING CONCERNS.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...WINTER WEATHER ADVISORY UNTIL NOON EST TODAY FOR VAZ081-
     089>091-093>098.
     WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
     VAZ073>078-084>086-099-100.
     WINTER WEATHER ADVISORY UNTIL 11 AM EST THIS MORNING FOR
     VAZ063-064-070>072-082-083.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 PM EST WEDNESDAY FOR ANZ630>632-
     634-654-656-658.
     SMALL CRAFT ADVISORY UNTIL MIDNIGHT EST WEDNESDAY NIGHT FOR
     ANZ650-652.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST WEDNESDAY FOR ANZ633-
     635>638.

&&

$$
SYNOPSIS...MAM
NEAR TERM...MAM
SHORT TERM...MAS/MAM
LONG TERM...LSA
AVIATION...LKB
MARINE...BMD
TIDES/COASTAL FLOODING...