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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KAKQ 280619
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
119 AM EST SAT FEB 28 2015

.SYNOPSIS...
ARCTIC HIGH PRESSURE SLOWLY BUILDS OVER THE REGION FROM TONIGHT
THROUGH SATURDAY...THEN SLIDES OFFSHORE SUNDAY. THE RESULT WILL
BE CONTINUED WELL BELOW NORMAL TEMPERATURES. A COLD FRONT PUSHES
ACROSS THE REGION MONDAY.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
NO BIG CHANGES NEC TO THE PREVIOUS FORECAST. STILL EXPECTING A
DRY NIGHT WITH SOME CLOUDS ESPECIALLY OVER WRN AREAS...AND LO
TEMPS IN THE MID TEENS TO LWR 20S AREA-WIDE.

PREVIOUS DISCUSSION...
WK S/W ALOFT MOVES AWAY TO THE NE THIS EVE...RESULTING IN AN END
TO THE SCT LGT SN INVOF LWR MD ERN SHORE. OTRW...SFC HI PRES
(~1042MB) CONTS TO BUILD EWD THROUGH THE OH VLY...EVENTUALLY
REACHING THE FA LT TNGT. XPCG PCLDY-VRB CLDS OVRNGT. LO LVL CAA
WILL BE ONGOING BUT PDS OF CLDNS LIKELY TO PREVENT SHARP DROP IN
TEMPS ACRS MOST OF THE FA. LO TEMPS FM THE UPR TEENS TO L20S.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH MONDAY/...
SFC HI PRES RMNS OVR THE RGN ON SAT PROVIDING CONTD WELL BLO NORMAL
TEMPS. ANOTHER DAY OF PCLDY-VRB CLDS...GOING W/ HI TEMPS A LITTLE
CLOSER TO MAV GUID...MNLY FM 30 TO 35F.

NR ZONAL FLO ALOFT FM SAT NGT THROUGH MON WILL BRING INCRSG CHCS
FOR PCPN (AND GRADUALLY MILDER CONDS). HOW QUICKLY ANY PCPN FM THE
W ARRIVES RMNS UNCERTAIN (12Z/27 CONTS TO BE QUICKER THAN THE
GFS). A FASTER ARRIVAL ON SUN (MRNG/MIDDAY) WOULD RESULT IN A
HIGHER LIKELIHOOD OF MIXED P-TYPE...ESP FM CNTRL VA TO LWR MD ERN
SHORE. WILL TREND POPS UP SLGTLY FM W-E BY SUN AFTN...W/ HIGHEST
POPS W OF I 95 (TO 30%). OTRW...WILL BRING WIDESPREAD CLDNS OVR
THE FA ON SUN WHICH WOULD LIMIT ANY WARMUP. LO TEMPS SAT NGT FM
THE UPR TEENS TO M20S. HI SUN IN THE U30S FAR N TO M40S SE.

SFC LO PRES WILL TRACK INTO NEW ENGLAND BY MON...W/ ITS
ASSOCIATED CDFNT PUSHING ACRS THE FA. WILL HAVE HI CHC TO LIKELY
POPS SUN NGT INTO MON. THERE IS A VERY LO PROB ATTM FOR MIXED
P-TYPE SUN EVE (N PORTION)...OTRW XPCG RA (AS PRIMARY P-TYPE) AND
TEMPS TO HOLD STEADY OR RISE A BIT SUN NGT (THROUGH THE 30S/L40S
SE). HOW QUICKLY CDFNT EXITS MON AFTN WILL DETERMINE ANY CLRG
TAKING PLACE W-E. WILL HOLD ONTO 40-50% POPS ON MON ACRS MOST OF
THE FA. HI TEMPS FM THE U40S TO M50S.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
HIGH PRESSURE BUILDS INTO THE REGION MONDAY NIGHT. THE FLOW ALOFT IS
ZONAL...SO ONLY PARTIAL CLEARING IS EXPECTED. LOWS SHOULD RANGE FROM
THE MID/UPPER 20S N...TO LOW 30S S. THE HIGH SHIFTS OFFSHORE TUESDAY
AS LOW PRESSURE TRACKS INTO THE OHIO VALLEY. THE ATTENDANT WARM
FRONT LIFTS THROUGH THE REGION LATER TUESDAY INTO TUESDAY NIGHT. THE
BEST FORCING FOR PCPN WILL TRACK N OF THE REGION...SO THE HIGHEST
POPS WILL BE ACROSS NRN PORTIONS...WITH A LESSER CHC TO THE S.
TUESDAY SHOULD BE CLOUDY AND COOL WITH MOST OF THE AREA WITHIN A
RESIDUAL CAD-WEDGE. HIGHS SHOULD RANGE FROM AROUND 40 NW...TO NEAR
50 SE. THE CURRENT FORECAST SHOULD LOWS ONLY DROPPING A FEW DEGREES
TUESDAY EVENING...BEFORE RISING OVERNIGHT. 27/00Z AND 12Z RUNS OF
THE ECMWF SUGGEST THE POTENTIAL FOR HIGHS WELL INTO THE 70S
WEDNESDAY. HOWEVER...THE GFS HAS BEEN CONSISTENTLY QUICKER WITH THE
FRONTAL PASSAGE AND HENCE HAS MORE CLOUD COVER/HIGHER POTENTIAL FOR
-RA. THE 27/12Z CMC IS CLOSER TO THE ECMWF. AT THIS TIME...HIGHS
HAVE BEEN TRENDED UPWARD INTO THE LOW/MID 60S AWAY FROM THE
COASTS...WHICH REFLECTS A CONSENSUS MODEL BLEND. GFS/ECMWF EACH HAVE
THE FRONT THROUGH THE REGION BY THURSDAY...WITH ANAFRONTAL PCPN IN
ITS WAKE. THE AIRMASS BEHIND THIS FRONT IS ONCE AGAIN ARCTIC IN
ORIGIN. THE QUESTION IN WHETHER OR NOT THE COLD AIR WILL COME IN
QUICK ENOUGH TO PRODUCE A CHANGEOVER TO -SN (PRIMARILY N/NW
PORTIONS). THIS PORTION OF THE FORECAST IS CONSIDERED LOW CONFIDENCE
AT THIS TIME...SO NO MENTION OF -SN WILL BE INCLUDED. TEMPERATURES
ARE EXPECTED TO BE WELL BELOW NORMAL AGAIN BY LATER NEXT WEEK WITH
CURRENT FORECAST HIGHS IN THE UPPER 30S TO MID 40S...WITH LOWS IN
THE LOW/MID 20S THURSDAY/FRIDAY NIGHTS.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
VFR CONDITIONS WILL PERSIST THROUGH THE 06Z TAF PERIOD AS HIGH
PRESSURE BUILDS OVER THE AREA. THE AIRMASS MOVING INTO THE AREA IS
MUCH DRIER THAN LAST NIGHT AND EVEN WITH WIDESPREAD SNOWCOVER...ONLY
EXPECTING SPOTTY SHALLOW GROUND FOG TO DEVELOP...IF ANY. A WEATHER
DISTURBANCE CROSSES THE OHIO VALLEY OVERNIGHT AND SPREADS MID TO
HIGH LEVEL CLOUDS INTO THE REGION FROM THE WSW TODAY.

MOISTURE RETURNS TO THE LOCAL AREA SUNDAY MORNING IN THE PRESENCE
OF A RETREATING COLD AIRMASS. THIS WILL POSE A THREAT FOR LIGHT
-FZRA/-PL AT KRIC...KSBY...AND POTENTIALLY KPHF FROM ROUGHLY 12Z-18Z.
LIGHT RAIN LINGERS ALL TAF SITES AFTER 18Z. DRY WX RETURNS BY MONDAY.

&&

.MARINE...
ANOTHER ARCTIC FRONTAL BOUNDARY IS CROSSING THE REGION THIS
AFTERNOON. THE CAA SURGE IS THE WAKE OF THE FRONT IS RATHER MINIMAL.
HOWEVER...LOW-END SCA CONDITIONS ARE EXPECTED ACROSS THE BAY AND
EVENTUALLY THE SOUND GIVEN THE NATURE OF THE AIRMASS. THE SCA FOR
THE BAY HAS BEEN EXTENDED THROUGH 15Z SATURDAY AS LOW-END SCA
CONDITIONS COULD PERSIST INTO THE MORNING. NNE FLOW OVER THE OCEAN
WILL LIKELY KEEP SEAS AOA 5FT...ESPECIALLY OFF THE COASTS OF SE VA
AND THE CURRITUCK OUTER BANKS. SEAS ARE PRESENTLY ~6FT OFF THE
CURRITUCK OUTER BANKS AND THERE IS A POTENTIAL FOR SEAS TO BUILD TO
7-8FT LATER TONIGHT (6-7FT NEARSHORE). HIGH PRESSURE BUILDS INTO THE
REGION SATURDAY AND SATURDAY NIGHT AND SHIFTS OFFSHORE SUNDAY...WITH
A COLD FRONT MOVING THROUGH THE REGION MONDAY...FOLLOWED BY A
NORTHERLY SURGE. HIGH PRESSURE RETURNS MONDAY NIGHT...WITH LOW
PRESSURE APPROACHING FROM THE W TUESDAY ALLOWING THE WIND TO BECOME
SSW TUESDAY NIGHT INTO WEDNESDAY.

&&

.CLIMATE...
RECORDS AT RICHMOND AND NORFOLK DATE BACK INTO THE LATE
1800S...WITH SOME NOTABLE TOP TEN RANKS IN SNOW AND TEMPERATURE
VERY LIKELY.

AVG TEMPERATURE FOR FEBRUARY THROUGH THE 26TH:

RICHMOND: 31.5 F (-9.2 FROM AVG). THIS WOULD RANK AS THE 6TH
COLDEST FEB ON RECORD AND THE COLDEST SINCE 1979.

NORFOLK: 32.8 F (-9.7 FROM AVG). THIS WOULD RANK AS THE 4TH
COLDEST FEB ON RECORD AND THE COLDEST SINCE 1978.

SNOWFALL FOR FEBRUARY THROUGH THE 26TH:

* RICHMOND: 12.2" (SNOWIEST FEB OCCURRED IN 1983 WITH 21.4"). THIS
  MOVES RICHMOND UP TO #9 ALL TIME FOR FEB.

* NORFOLK: 11.5" (SNOWIEST FEB OCCURRED IN 1989 WITH 24.4"). THIS
  MOVES NORFOLK UP TO #7 ALL TIME FOR FEB.

ANOTHER ROUND OF COLD WEATHER IS EXPECTED THIS WEEKEND.

RECORD LOW TEMPERATURES (SUNDAY MORNING):

          3/1      ALL TIME RECORD LOW TEMPERATURES FOR MARCH
        _______      __________________________________________
RIC11/1937      10 MARCH 4 2009
ORF18/1980      14 MARCH 14 1888
SBY     13/1980      1 MARCH 3,4 2009 AND MARCH 9 1911
ECG     16/1937      16 MARCH 1 1937 AND MARCH 4 1943

RECORD LOW HIGH TEMPERATURES (TODAY):

            2/28
          _______
RIC       28/1934
ORF       30/1934
SBY       29/1934
ECG       33/1934

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 10 AM EST THIS MORNING FOR
     ANZ630>634.
     SMALL CRAFT ADVISORY UNTIL 6 AM EST EARLY THIS MORNING FOR
     ANZ650-652-654.
     SMALL CRAFT ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR ANZ656-
     658.

&&

$$
SYNOPSIS...ALB/SAM
NEAR TERM...ALB/MAS/SAM
SHORT TERM...ALB/SAM
LONG TERM...AJZ
AVIATION...JDM/DAP
MARINE...AJZ
CLIMATE...AKQ