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000
FXUS61 KAKQ 040400
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1100 PM EST TUE MAR 3 2015

.SYNOPSIS...
A WARM FRONT LIFTS NORTHEAST ACROSS THE REGION TONIGHT...FOLLOWED
BY A COLD FRONT SLOWLY CROSSING THE AREA WEDNESDAY AFTERNOON
THROUGH WEDNESDAY NIGHT. THE FRONT WILL STALL OVER NORTH CAROLINA ON
THURSDAY...WITH A WAVE OF LOW PRESSURE MOVING ALONG THE FRONT INTO
THURSDAY NIGHT. THIS WILL BRING ANOTHER ROUND OF WINTRY WEATHER TO
THE AREA...FOLLOWED BY COLD AND DRY CONDITIONS ON FRIDAY.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
CURRENT ANALYSIS DEPICTS _985 MB SFC LOW PRESSURE OVER ONTARIO
CANADA...WITH WEAKENING SFC HIGH PRESSURE WELL OFF THE MID ATLC
COAST. AREA 00Z SOUNDINGS SHOW A STRONG LOW LEVEL INVERSION IN
PLACE...PARTICULARLY AT GSO. RADAR CONTINUES TO SHOW SPOTTY AREAS
OF LIGHT RAIN OR DRIZZLE. TEMPERATURES ARE HOVERING IN THE MID 30S
MOST AREAS...WITH LOWER-MID 40S OVER NE NC AND FAR SE VA. LOOKS
LIKE INVERSION WILL HOLD FOR MUCH OF THE OVERNIGHT PERIOD OVER
INTERIOR SECTIONS EVEN WITH A 5-10 KT SW SFC WIND. HAVE ADDED
AREAS OF DRIZZLE AND FOG TO THE FORECAST TO ACCOUNT FOR THIS...ALONG
WITH LIKELY POPS FOR MEASURABLE RAIN AMTS GENLY LESS THAN 0.10" OVERNIGHT.
LOWERED TEMPS OVER CENTRAL AND SOUTH CENTRAL VA AND INTERIOR NE NC
TO CURRENT READINGS IN THE MID/UPPER 30S. WHILE TEMPS WILL
ACTUALLY RISE OVERNIGHT...THINK THE RISE WILL BE VERY GRADUAL OVER
MOST OF THE AREA DUE TO THE STEEP LOW LEVEL INVERSION (LAMP
GUIDANCE HAS BEEN VERIFYING SEVERAL DEGREES TOO WARM THIS EVENING
AND LOOKS TO WARM THE TEMPS OVERNIGHT TOO RAPIDLY). THUS...SLOWED
THE WARM-UP THROUGH 12Z SIGNIFICANTLY...WITH READINGS STILL
HOLDING IN THE 30S TO LOWER 40S THROUGH 12Z WELL INLAND AS AREAS
NEAR THE SE VA AND NE NC COAST RISE THROUGH THE 40S INTO THE LOWER
50S. AS FOR FOG...THE SW WIND SHOULD TEND TO KEEP DENSE FOG WITH
VSBYS DOWN TO 1/4SM OR LESS FROM BECOMING WIDESPREAD...BUT EXPECT
AREAS OF FOG WITH VSBYS FROM 1/2SM TO 2SM TO BECOME COMMON AFTER
MIDNIGHT.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
WED THRU THU NGT...EXPECT VARIABLE WX CONDITIONS WITH VERY MILD
TEMPS ON WED/WED NGT ALONG WITH RAIN OR RAIN SHOWERS...THEN MUCH
COLDER TEMPS RETURNING FOR THU/THU NGT WITH RAIN CHANGING TO SLEET
AND/OR SNOW. AT THIS TIME...GOING WITH A BLEND OF THE 12Z
GFS/ECMWF WITH RESPECT TO TIMING OF FRNTL PASSAGE AND TEMP
PROFILES WITH THE CHANGEOVER FM RAIN TO SLEET AND/OR SNOW.

HIGHEST POPS FOR RAIN OR RAIN SHOWERS WILL REMAIN ACRS THE NRN
HALF OF THE REGION DURING WED...AS THE FRONT SLOWLY SINKS SE ACRS
THE AREA. MAX TEMPS WILL RANGE FM THE MID 50S EXTRM N (WHERE SKIES
REMAIN OVC ALL DAY)...TO THE LWR 70S S/SE WHERE SKIES SHOULD BECOME
PARTLY SUNNY BY LATE MORNING.

COLD FRONT WILL BE S OF THE ENTIRE REGION BY 12Z THU...THEN WAVES
OF LO PRES WILL MOVE NE ALNG THE BNDRY AND OFF THE MID ATLC CST
THU INTO THU NGT...AS ANOTHER AREA OF ARCTIC SFC HI PRES BLDS TWD
THE MS/OH VALLEYS. COMPROMISE OF 12Z GFS/ECMWF THERMAL PROFILES
SHOWS RAIN BECOMES MIXED WITH SLEET...THEN CHANGES TO SNOW/SLEET
THEN ENDING AS SNOW FM NNW TO SE ACRS THE FA...FM THU MORNG INTO
THU EVENG. STILL SOME UNCERTAINLY WITH RESPECT TO TIMING THOSE
TRANSITIONS...AND AT THIS TIME WITH BUFKIT SOUNDINGS SHOWING A
SLOW TRANSITION TO ALL SNOW THINKING IS THAT SLEET OR SNOW/SLEET
MIX WILL KEEP TOTAL ACCUMULATIONS DOWN TO LESS THAN 4" ALL AREAS. EXPECT
AT LEAST LGT- MODERATE SNOW/SLEET ACCUMS OF 1 TO 3 INCHES ALNG AND
N OF A FARMVILLE TO PETERSBURG TO MELFA LINE BY EARLY THU NGT (AS
MUCH AS 3-4" POSSIBLE FAR NORTH)...WITH GENLY AN INCH OR LESS OVER
FAR SRN VA/NE NC (BULK OF ACCUMULATING SNOW/SLEET HERE THU
EVENING). DUE TO LINGERING MOISTURE THU EVENING OVER EXTREME SE
VA/NE NC...COULD SEE SLIGHTLY HIGHER TOTALS IN THESE AREAS...1-2".

ALNG WITH THE TRANSITION TO WINTRY PCPN...GUSTY NNE WNDS WILL BE
PUSHING COLDER AIR INTO THE REGION. LO TEMPS WED NGT WILL RANGE FM
THE LWR 30S N...TO THE LWR/MID 40S FAR S/SE. TEMPS ON THU WILL BE
STEADY OR FALLING INTO THE UPPER 20S N TO THE LOWER-MID 30S S BY
LATE AFTN.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
EXTENDED PERIOD WILL BE HIGHLIGHTED BY GENERALLY DRY CONDITIONS
AND A RETURN TO NEAR SEASONABLE NORMAL TEMPS.

MEDIUM RANGE GUIDANCE IN GENERAL CONSENSUS WITH THE UPPER FLOW
THRU THE EXTENDED...CHARACTERIZED BY RIDGING/BLOCKING OVER THE WRN
CONUS/ERN PACIFIC AND BROAD TROUGHING OVER THE CNTRL AND ERN
CONUS. TO BEGIN THE PERIOD...COLD/DRY 1030+MB ARCTIC HIGH PRESSURE
CENTERS OVER THE MID-ATLANTIC REGION. THURSDAYS COLD FRONT LOCATES
OFF THE COAST...EXTENDING SWWD INTO THE NRN GULF. H85 TEMPS DROP
TO AROUND -8C FRI (~-1 STD DEV)...SLIGHTLY WARMER THAN DEPICTED 24
HRS AGO. HIGHS FRI GENERALLY IN THE LOW-MID 30S INLAND AND UPPER
20S-LOW 30S COASTAL AREAS. AIRMASS MODIFIES FRI NIGHT-SAT AS THE
COLD/DRY AIR RETREATS NWD. HIGH PRESSURE REMAINS OVER THE REGION
SAT...WITH LIGHT RETURN FLOW HELPING TO MODERATE LOW LEVEL
THICKNESSES. TEMPS WARM INTO THE UPPER 40S-LOW 50S INLAND AND LOW-
MID 40S COASTAL AREAS. SKY AVG MOSTLY SUNNY-PARTLY CLOUDY. HIGH
PRESSURE REMAINS OVER THE REGION SUN...RESULTING IN CONTINUED DRY
AND WARMING CONDITIONS. HIGHS IN THE LOW-MID 50S INLAND AND LOW
40S TO UPPER 40S COASTAL AREAS. ATTENTION THEN TURNS OUT
WEST...WHERE MODELS CONTINUE TO STRUGGLE HANDLING SPLIT/BLOCKY
FLOW AND SRN STREAM ENERGY OVER THE DESERT SW/BAJA. GOOD NEWS IS
THAT NOW THE DETERMINISTIC ECMWF HAS TRENDED DRY SUN NIGHT-EARLY
NEXT WEEK...MATCHING THE GFS AND ENSEMBLES. HOWEVER...SPLIT FLOW
CONTINUES RESULTING IN LOW CONFIDENCE EARLY NEXT WEEK. FRONT OVER
THE GULF WILL ATTEMPT TO AMPLIFY AND LIFT NWD AS SRN STREAM ENERGY
APPROACHES...BUT WILL KEEP POPS SILENT. HIGHS EARLY NEXT WEEK (MON
AND TUES) CONTINUE TO WARM INTO THE MID 50S INLAND AND LOW-UPPER
40S COASTAL AREAS THANKS TO COLD WATER.

&&

.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
AS OF 00Z...THE SURFACE MAP SHOWS A WARM FRONT REACHING FROM
MICHIGAN ACROSS FAR WRN PA AND SNAKING S/SW ACROSS WV. A COLD FRONT
FROM A LOW OVER LAKE SUPERIOR ACROSS WRN INDIANA AND INTO SOUTHERN
MISSOURI. THE MID ATLANTIC STATES WILL BECOME LARGELY WARM SECTORED
ON WEDNESDAY INCLUDING ALL THE TAF SITES EXCEPT SBY.

TUESDAY EVENING HAD AN OVERCAST CLOUD DECK CONTINUING WITH LOWERING
CEILINGS. MOS FORECASTS SUPPORT LOWERING OF THE CIGS TO IFR DURING
THE FIRST SIX HOURS. PCPN HAS BEEN SPARSE AND SUPPORT FOR MORE THAN
LIGHT DRIZZLE OR BRIEF SHOWERS IS NOT PRESENT. HAVE LIMITED THE PCPN
IN THE TAFS COMPARED WITH WHAT IS IN THE NAM MOS. THE BEST CHANCE
FOR RAIN IS AT SBY THROUGHOUT WEDNESDAY AFTN. WINDS WILL BE FROM THE
S/SW OVERNIGHT AND SW ON WEDNESDAY AND BECOME GUSTY AT TIMES...
ESPECIALLY ON WEDNESDAY EXCEPT AT SBY WHERE WINDS SHOULD STAY UNDER
10 KNOTS.

OUTLOOK...RAIN INCREASES FROM THE NORTH WEDNESDAY NIGHT AND ON
THURSDAY BECOMES MIXED PCPN NRN PORTIONS. BY LATE IN THE DAY...PCPN
BECOMES SNOW NRN PORTIONS AND MIXED PCPN SRN PORTIONS. PCPN BECOMES
MAINLY SNOW THURSDAY EVENING BEFORE ENDING FROM THE NW. ANY SNOW
ACCUMULATIONS ARE EXPECTED TO BE AROUND 2 INCHES RIC AND SBY AND
AROUND AN INCH SE PORTIONS. A GUSTY NORTHERLY WIND WILL DEVELOP
ALONG THE COAST THURSDAY. HIGH PRESSURE SETTLES WITH DRY WEATHER
FRIDAY THROUGH SUNDAY.

&&

.MARINE...
HIGH PRESSURE HAS CENTERED OFFSHORE THIS AFTERNOON AS A WARM
FRONT APPROACHES FROM THE SOUTH. THE RESULT IS LIGHT E-SE WINDS
AOB 10 KT OVER THE WATER. WAVES GENERALLY 1-2 FT AND SEAS 2-4 FT.
SW WINDS INCREASE TONIGHT AS A WARM FRONT LIFTS OVER THE WATERS.
LLJ INCREASES TO 50+KT TONIGHT...BUT WAA AND COLD WATER WILL
RESULT IN A SHARP INVERSION OVER THE WATER. THIS WILL PREVENT THE
HIGHER VELOCITY WINDS FROM MIXING TO THE WATER. THUS...SCA
CONDITIONS ARE NOT EXPECTED BUT CANNOT RULE OUT A FEW GUSTS OF 20
KT LATE TONIGHT. HAVE CAPPED WINDS AT 15 KT IN THE BAY AND 20 KT
IN THE COASTAL WATERS. SEAS REMAIN AOB 4 FT. COLD FRONT SLOWLY
CROSSES THE WATER NW TO SE WEDS...BECOMING NEARLY STATIONARY NEAR
THE NC/VA BORDER WEDS EVENING AS LOW PRESSURE TRACKS ALONG THE
BOUNDARY. FLOW BECOMES NLY POST FRONTAL...BUT DECREASES TO AROUND
10-15 KT AS CAA LAGS BEHIND. FRONT CLEARS THE WATERS LATE WEDS
NIGHT...WITH CAA SURGE ARRIVING INTO THE REGION LATE WEDS NIGHT.
SCA CONDITIONS EXPECTED ALL WATER THURS MORNING...PERSISTING THRU
THURS NIGHT. GUIDANCE INDICATING LOW END GALE CONDITIONS POSSIBLE
LATE THURS INTO THURS NIGHT IN THE SRN COASTAL WATERS AND
CURRITUCK SOUND...CLOSEST TO THE STRONGEST GRADIENT. SEAS BUILD TO
4-7 FT (UP TO 8 FT SRN COASTAL WATERS) THURS-THURS NIGHT. HIGH
PRESSURE BUILDS OVER THE WATERS FRI...RESULTING IN DIMINISHING
WINDS AND SLOWLY SUBSIDING SEAS. SUB-SCA CONDITIONS PREVAIL THRU
THE WEEKEND THANKS TO HIGH PRESSURE.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...NONE.

&&

$$
SYNOPSIS...LKB
NEAR TERM...LKB
SHORT TERM...LKB/TMG
LONG TERM...SAM
AVIATION...LSA
MARINE...SAM