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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 271012 CCA
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
500 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/...
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 SCATTERED REPORTS OF ~1" ALONG THE
NORTHERN NECK INTO THE PENINSULA, WITH 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 /09Z TUESDAY THROUGH SATURDAY/...
SNOW SHOWERS AFFECTING THE TAF SITES AS OF 06Z (RAIN CHANGING TO
SNOW AT KECG)...WITH EITHER LOW MVFR OR IFR CONDITIONS THROUGHOUT.
SOME VARIABILITY IS ANTICIPATED IN CIGS/VSBYS THROUGH 12Z...WILL
AVG IFR WITH CIGS JUST BELOW 1000 FT AND VSBYS OF 2-3SM. COULD
BRIEFLY SEE LIFR CONDS IN HEAVIER SNOW SHOWERS (PROBABLY MOST
LIKELY AT KORF). GUSTY N/NW WINDS TO AROUND 25 KT AT
ORF/KECG...AROUND 20 KT ELSEWHERE.

CONDITIONS WILL GRADUALLY IMPROVE AFTER 12Z...ALTHOUGH WILL HANG
ONTO IFR CIGS AT MOST SITES THROUGH AROUND 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...
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 SURGE IN
SPEEDS BUT STILL WITHIN GALES FOR NRN OCEAN AND WITHIN STRONG SCA
FOR BAY/RIVERS/SOUND. 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. BASED ON CURRENT FORECAST AND MODEL
GUIDANCE...GALES MAY BE REPLACED BY STRONG SCA FLAGS PRIOR TO 7 PM
THIS EVENING. WILL MONITOR TRENDS IN WINDS/SEAS AS THE DAY
PROGRESSES. 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 NWLLY 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. WILL
MONITOR TRENDS THROUGH MID MORNING...BUT WILL NOT ISSUE ANY
COASTAL FLOOD ADVSIORY 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...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
     MDZ021>025.
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.
     GALE WARNING UNTIL 10 PM EST THIS EVENING 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...AKQ