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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 270612
AFDAKQ

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

.SYNOPSIS...
A COASTAL LOW PRESSURE SYSTEM WILL RAPIDLY INTENSIFY OVERNIGHT AS IT
TRACKS NORTH NORTHEAST OFF THE MID ATLANTIC AND NEW ENGLAND
COASTS. THE LOW WILL MOVE INTO THE CANADIAN MARITIMES ON
WEDNESDAY...AS HIGH PRESSURE SLOWLY BUILDS OVER THE MID ATLANTIC.
A COLD FRONT WILL CROSS THE AREA THURSDAY NIGHT...FOLLOWED BY HIGH
PRESSURE THROUGH SATURDAY.

&&

.NEAR TERM /THROUGH TODAY/...
UPDATE AS OF 10 PM EST...
NO CHANGES TO THE INHERITED WSW HEADLINES THIS EVENING...ALTHOUGH
CONFIDENCE IN SEEING MORE THAN AN INCH OF SNOW WITHIN THE ENTIRE
WSW IS LOW. LATEST OPERATIONAL 00Z NAM REMAINS LESS THAN IMPRESSED
WITH POTENTIAL SNOWFALL ACCUMULATIONS THRU TUESDAY MORNING. OUTSIDE
OF THE BATCH OF RAIN MOVING SOUTH OVER THE CHES BAY/EASTERN SHORE
ATTM...THE NAM AND LATEST HRRR ARE VOID OF ANY OTHER ORGANIZED
AREAS OF PCPN. AT LEAST WE HAVE BEGUN TO SEE SIGNS OF LIGHT SNOW
DEVELOPING ACROSS THE PIEDMONT/I-95 CORRIDOR THIS EVENING AS
COLDER AIR ALOFT...ASSOCIATED WITH THE APPROACHING UPPER
TROUGH...CONTINUES TO MOVE IN. HOWEVER...OTHER THAN COUNTING ON
THE UPPER TROUGH ITSELF TO GENERATE MEANINGFUL SNOW SHOWERS
OVERNIGHT/TUES MORNING...THE AREA WILL REMAIN TO FAR REMOVED FROM
THE DEEPENING SFC LOW OFFSHORE FOR SIGNIFICANT SNOW. HAVE CONTINUED TO
TRIM SNOW ACCUMULATION WORDING IN THE WSW`S THIS EVENING...AS A
COATING/HALF INCH OF SNOW MAY BE ABOUT THE WORST CASE SCENARIO
MOST PLACES. WILL MAINTAIN GENERALLY 2-3" ON THE LOWER MD EASTERN
SHORE CLOSEST TO THE SFC LOW...BUT A FURTHER REDUCTION IN SNOW
TOTALS MAY BE NECESSARY ON THE NEXT SHIFT. LOWS TONIGHT IN THE UPR
20S NW TO THE MID 30S SE. GRADUALLY IMPROVING CONDITIONS LATER
TUES MORNING INTO THE AFTERNOON.

PREVIOUS DISCUSSION...
MAIN FORECAST CHANGE WAS TO START TRIMMING BACK ON INHERITED
WINTER WX ADVSRYS AS THE LIKELIHOOD FOR 1-3IN OF SNOW HAS DECREASED
OVER MANY AREAS. WPC AND MUCH OF 12Z GUIDANCE SUPPORT THIS
IDEA...WITH THE BEST CHANCE FOR ADVSRY-LEVEL SNOWFALL STILL OVER
THE LWR MD ERN SHORE WHERE 2-4IN IS PSBL. DO NOT THINK NORFOLK AND
RICHMOND METRO AREAS WILL RECEIVE AOA 2IN...BUT WITH THE HEADLINE
ALREADY OUT AND THE POTENTIAL FOR UP TO AN INCH TO PSBLY CAUSE
SOME IMPACTS DURING THE MORNING COMMUTE...WILL KEEP THOSE AREAS
(AND AREAS N AND E) IN THE ADVSRY FOR NOW. ANOTHER ISSUE IS
TEMPS...WITH PARTS OF THE AREA STAYING JUST A TAD ABOVE FREEZING.
WILL UPDATE AS NEEDED THIS EVENG AND TNGT.

AS FOR PCPN...EXPECT MAINLY DRY CONDS DURING THE NEXT FEW HRS
ASIDE FM WORCESTER CNTY WHERE AN AREA OF RA HAS BEEN PERSISTENT.
BETTER CHANCE FOR RAIN ARRIVES THIS EVENG AS SFC LO PRES DEVELOPS
OFFSHORE. POPS RANGE FM 40-50% SW TO 70-80% NE. THE RA WILL
TRANSITION TO A RA/SN MIX THEN SN FM NW TO SE TNGT. TOTAL QPF WILL
BE UP TO A QUARTER INCH. LO TEMPS WILL RANGE FM THE UPR 20S FAR
NW TO MID 30S SE. PCPN WILL END FM W TO E ON TUE AS THE SFC LO
ADVANCES TOWARDS THE GULF OF ME AND NW CAA FLOW LEADS TO GUSTS TO
25-30 MPH NR THE CST AND LWR ERN SHORE. HI TEMPS ONLY IN THE MID
30S TO LWR 40S UNDER A CLOUDY-MSTLY CLOUDY SKY.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
IMPROVING WX FOR THE SHORT TERM PERIOD. FOR TUE
NIGHT/WED...AFOREMENTIONED CSTL LO PULLS TOWARDS THE CANADIAN
MARITIMES AS SFC HI PRES SLOWLY BLDS IN FM THE W. EXPECT
DECREASING CLOUDS TUE NIGHT WITH NW WINDS. LO TEMPS WILL RANGE
THRU THE 20S...WITH WIND CHILLS IN THE TEENS IN MOST LOCATIONS.
COOL TEMPS INTO WED AS WELL...WITH HIGHS ONLY RANGING FM THE MID
30S OVER THE LWR ERN SHORE TO THE UPR 30S TO LWR 40S ELSEWHERE.
DRY AGAIN FOR WED NIGHT WITH SIMILAR TEMPS AS TUE NIGHT.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
THE LONG TERM PERIOD WILL FEATURE BLO NORMAL TEMPS WITH A
PROGRESSIVE NORTHERN STREAM. ONE LOW PRESSURE SYSTEM MOVES FROM THE
MIDWEST TO THE NORTHEAST STATES SENDING A COLD FRONT THROUGH THE
AREA LATE THURSDAY NIGHT/EARLY FRIDAY MORNING. A CHC OF RAIN IS IN
THE FORECAST MAINLY FOR THURSDAY NIGHT WITH LIGHT SNOW PSBL FAR NRN
PORTIONS OF THE AREA. 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 /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
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.
-- End Changed Discussion --

&&

.MARINE...
EXTENDED PERIOD OF SCA HEADLINES FORECAST THRU WEDS.

LOW PRESSURE HAS LOCATED JUST OFF THE NC/VA COAST THIS AFTERNOON.
THE LOW HAS INTENSIFIED SLIGHTLY...RESULTING IN AN UPTICK OF N-NE
WINDS OVER THE WATERS. BEGINNING TO SEE 20 KT GUSTS OVER THE
BAY/LOWER JAMES WITH GUSTS OF 30 TO 35 KT OVER THE NRN COASTAL
WATERS. SEAS HAVE RESPONDED...BUILDING TO 7 FT AT BUOY 44009. WINDS
WILL CONTINUE TO RAMP UP THRU LATE AFTERNOON WITH SOLID SCA
CONDITIONS (GUSTS TO 30 KT) EXPECTED ACROSS ALL WATERS TONIGHT AS
THE LOW INTENSIFIES RAPIDLY AND LIFTS AWAY FROM THE COAST. LOW LEVEL
CAA ALSO INTENSIFIES. GALE CONDITIONS WITH GUSTS UP TO 40 KT
EXPECTED ACROSS THE NRN COASTAL WATERS...CLOSEST TO THE STRONGEST
GRADIENT WINDS AND CAA. SEAS BUILD TO 7 TO 12 FT IN THE NRN WATERS
AND 5 TO 8 FT IN THE SRN WATERS TONIGHT. AS THE LOW LIFTS
AWAY...FLOW BACKS TO THE NW...KEEPING HIGH SEAS FROM REACHING THE
BEACHES. NO HIGH SURF PLANNED ATTM. LITTLE CHANGE TUES AS STRONG NW
FLOW PERSISTS BTWN LOW PRESSURE OFF THE NE COAST AND HIGH PRESSURE
OVER THE OH VALLEY. GALE CONDITIONS PERSIST OVER THE NRN COASTAL
WATERS THRU EARLY TUES EVENING...BEFORE SUBSIDING TO SOLID SCA
CONDITIONS. SEAS SUBSIDE TO 5-8 FT TUES-TUES NIGHT. HIGH PRESSURE
FINALLY BUILDS OVER THE WATERS LATE WEDS...ALLOWING WINDS TO
DIMINISH AOB 15 KT. SEAS SUBSIDE THRU WEDS EVENING. HIGH PRESSURE
REMAINS OVER THE WATERS THURS IN ADVANCE OF THE NEXT CLIPPER FRONT
SET TO CROSS THE WATERS THURS NIGHT.

&&

.TIDES/COASTAL FLOODING...
-- Changed Discussion --
LOW PRESSURE INTENSIFIES RAPIDLY OFF THE MID-ATLANTIC COAST
OVERNIGHT AND TUESDAY. THE RESULT WILL BE A PERIOD OF STRONG NORTH
TO NORTHWEST WINDS OVER THE WATERS. TIDAL ANOMALIES ARE FORECAST
TO REACH 1.5 TO 2.0 FT IN THE LOWER BAY AND AROUND 2.0 FT FOR THE
COASTAL AREAS OF THE ERN SHORE. MINOR FLOODING THRESHOLDS ARE
ANTICIPATED AT OCEAN CITY INLET...WITH A WATER LEVEL OF AROUND 4.0 FT.
GUIDANCE CONTINUES TO TREND DOWN FROM MODERATE FLOODING...WHICH
MAKES SENSE GIVEN A MORE NORTH TO NORTHWEST WIND DIRECTION. THE
COASTAL FLOOD WATCH HAS BEEN REPLACED WITH A COASTAL FLOOD
ADVISORY.

WATER LEVELS ARE EXPECTED TO REMAIN BELOW MINOR FLOODING THRESHOLDS
IN THE LOWER BAY...BUT WILL REACH SLIGHTLY ABOVE HIGHEST ASTRO
TIDE. ANOTHER PERIOD OF HIGH ANOMALIES ARE EXPECTED AGAIN TUESDAY...BEFORE
ANOMALIES DROP OFF TUE NGT/WED AS THE LOW LIFTS AWAY FROM THE
REGION. AFTER CURRENT ADVISORY ENDS MAY NEED TO PLACE ANOTHER ONE
IN EFFECT FOR THE TUE AFTN HIGH TIDE AT OCEAN CITY.
-- End Changed Discussion --

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...WINTER WEATHER ADVISORY UNTIL 1 PM EST THIS AFTERNOON FOR
     MDZ021>025.
     COASTAL FLOOD ADVISORY UNTIL 3 AM EST EARLY THIS MORNING FOR
     MDZ025.
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 6 PM EST WEDNESDAY FOR ANZ630>638-
     654-656-658.
     GALE WARNING UNTIL 10 PM EST THIS EVENING FOR ANZ650-652.
-- End Changed Discussion --

&&

$$
SYNOPSIS...JDM/MAS
NEAR TERM...JDM/MAS
SHORT TERM...MAS
LONG TERM...LSA
AVIATION...LKB
MARINE...SAM
TIDES/COASTAL FLOODING...AKQ