FXUS61 KAKQ 030851
AFDAKQ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
351 AM EST THU DEC 3 2009
.SYNOPSIS...
A COLD FRONT WILL MOVE OFFSHORE THIS MORNING. HIGH PRESSURE THEN
BUILDS BACK INTO THE AREA TODAY THROUGH FRIDAY. ANOTHER LOW
PRESSURE SYSTEM MOVES NORTHEAST ALONG THE CAROLINA COAST FRIDAY
NIGHT AND ACROSS THE VIRGINIA CAPES SATURDAY. HIGH PRESSURE BUILDS
BACK OVER THE REGION FOR SUNDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
AS OF 3 AM THIS MORNING...COLD FRONT CURRENTLY MVING FROM W TO E
ACROSS THE CWA...AND WILL PUSH OFFSHORE BY 7 AM THIS MORNING.
SCATTERED SHWRS WILL CONTINUE TO AFFECT COASTAL REGION BEFORE
THIS FRONT MVS OFFSHORE. IN THE WAKE OF THE FRONT...CLEARING OF
SKIES (FROM W TO E) THROUGHOUT THIS MORNING AND MUCH IMPROVED
(DRIER) WX FOR THE REST OF TODAY. TEMPS WILL BEGIN TO DROP A
COUPLE OF DEGS BEHIND THE FRONT...BUT THEN REMAIN STEADY IN THE
LOW-MID 60S BY LATE THIS MORNING. THEN AS CAA BEGINS TO SET IN
LATE THIS AFTN, TEMPS WILL BEGIN TO FALL INTO THE UPR 50S W OF
I-95. HIGHS TODAY WILL TECHNICALLY HAVE BEEN MET OVERNIGHT WHILE
THE FORECAST AREA WAS STILL IN THE WARM SECTOR.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
MOSTLY CLEAR TONIGHT AS CAA SETS IN ACROSS THE AREA. LOWS 35-45. SFC
HIGH PRES BUILDS BACK OVR THE MID ATLC THRU FRI...WHILE A MID-UPR
TROF DIGS ACROSS THE CENTRAL US. FRIDAY WILL BEGIN MSTLY SNY, BUT AS
HIGH LVL MSTR INCREASES OUT OF THE S (THANKS TO DEVLOPING SYS TO OUR
S) SKIES WILL BECOME MSTLY CLDY BY FRI EVENING. FRI SEASONABLE WITH
HIGHS IN THE 50S.
NXT SYSTM DVLPS OFF THE SE COAST FRI EVE. MSTR FROM THE SYSTM PROGGED
TO ADVANCE N LATE FRI NITE. WILL HAVE LOW CHC (LIQUID) POPS ACROSS NE
NC AND SERN VA CNTYS AFTR MIDNITE. LOWS IN THE 30S XCPT 40S SERN
AREAS.
NXT FCST CHALLENGE COMES SAT. CSTL LOW MOVES FRTHR OFFSHORE BUT
LAGGING UPR LVL NRGY PROGGED TO ENHANCE PCPN ACROSS THE AREA DRNG
AFTRN AND EVE. P-TYPE BECOMES AN ISSUE. NAM/SREF SOMEWHAT WRMR WITH
THE GFS COLDEST. THE TREND HERE IS FOR THE PCPN TO START OFF AS A
COLD RAIN OVR MOST OF THE FA...THEN MIX WITH (OR EVEN CHANGE) TO WET
SNOW DRNG THE AFTRN AS COLDER AIR COLLAPSES CRITICAL THICKNESS
TOWARD THE COAST. MAIN AND MOST CHALLENGING PART OF THIS FCST ATTM
WILL BE SFC TMPS. DESPITE STDY OR SLOWLY FALLING TMPS IN THE
AFTRN...SFC TMPS STAY ABV 32 DRNG THE DAY. SO ANY SNOW THAT DOES
FALL IS NOT XPCTD TO ACCUMULATE. WILL START OFF WITH A COLD RAIN
THEN HAVE A RAIN/SNOW MIX IN THE AFTRN MAINLY NW OF A
SBY-XSA-PTB-AVC LINE FOR NOW. XPCT LATER SHIFTS TO ADJUST THIS LINE
AS NEEDED.
&&
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
THE MODELS CONTINUE TO BE IN GOOD AGREEMENT IN THE EXTENDED RANGE
WITH THE OVERALL PATTERN. FOR THE FIRST SYSTEM ON SATURDAY
NIGHT...BOTH EMCWF AND GFS SHOW THE SYSTEM EXITING TOWARD THE
NE...BUT WITH THE SHORTWAVE STILL TO CROSS THE REGION AND
TEMPERATURES DROPPING BEHIND THE EXITING SYSTEM...A CHANGE OVER TO
ALL SNOW IS A POSSIBILITY...ESPECIALLY FOR AREAS ALONG AND WEST OF
THE I-95 CORRIDOR.
HIGH PRESSURE QUICKLY BUILDS IN ON SUNDAY...FACILITATING CLEARING
CONDITIONS. WITH HEIGHTS BUILDING BACK NORTHWARD...SHOULD SEE
TEMPERATURES MODERATE SOME ON MONDAY...BUT THE DEVELOPING SW FLOW
ALOFT LOOKS TO PUSH LOTS OF CIRRUS ACROSS THE REGION...WHICH MAY
HOLD THE HIGHS DOWN A FEW DEGREES...SO FOR NOW HAVE STAY JUST ON THE
COOL SIDE OF THE GUIDANCE.
FOR TUESDAY INTO WEDNESDAY...THE MODELS ARE SHOWING QUITE A BIT OF
DIFFERENCES IN THE DETAILS AS THE GFS IS PHASING THE APPROACHING
SYSTEM OVER THE PLAINS AS IT MOVE EASTWARD INTO THE OHIO VALLEY
WHILE THE ECMWF IS SLOWER TO PHASE...NOT DOING SO UNTIL IT REACHES
THE EASTERN SEABOARD. IN EITHER CASE...EXPECT TO SEE THE CLOUDS
INCREASING WITH A GOOD CHANCE OF RAIN TUES NIGHT INTO WED...BUT THE
AMOUNTS AND DURATIONS COULD VARY GREATLY WITH THE DIFFERENT
SCENARIOS. SO FOR NOW HAVE GONE WITH A GOOD CHANCE OF RAIN FOR THE
PERIOD WITH MILD TEMPERATURES.
&&
.AVIATION /09Z THURSDAY THROUGH MONDAY/...
GENERALLY EXPECT IMPROVING CONDITIONS THIS MORNING...A FEW SCTD
SHWRS WILL CONTINUE THROUGH 12Z...MAINLY TOWARDS THE COAST...ALONG
WITH CIGS 1-2 KT FT. OTHERWISE...SKIES SHOULD BECOME PTLY TO MOSTLY
CLEAR THEREAFTER...WITH A BREEZY WSW FLOW THROUGH EARLY AFTN
(GUSTING TO ABOUT 25 KT). WINDS DIMINISH TO 10-15 KT OR LESS AFTER
18/19Z AND VEER TO THE W OR WNW. QUIET CONDITIONS OVERNIGHT AND
FRIDAY AS HIGH PRESSURE TAKES CONTROL (INCREASING MID/HIGH CLOUDS
DURING THE DAY FRI).
A COASTAL SYSTEM LOOKS TO AFFECT THE REGION LATE FRI NGT THROUGH SAT
NIGHT...WITH A PERIOD OF LOWER CIGS/VSBYS AND PRECIPITATION POSSIBLE
SAT. THERE IS A CHANCE FOR A MIX TO SNOW AT RIC/SBY BY LATER SAT
AFTN/SAT EVENING.
&&
.MARINE...
CURRENT EVENT IS WINDING DOWN...AND AS THE CASE TYPICALLY IS...GALES
WERE DIFFICULT TO ATTAIN ON A SOUTHERLY FLOW. HAVE SEEN SEVERAL
BRIEF OBS W/ GUSTS OVER 40 KT AIDED BY CONVECTION...BUT FOR THE MOST
PART ONLY THE COAST REALLY ATTAINED ANY APPRECIABLE PERIOD OF GALES
FORCE WINDS. HAVE REPLACED THE GALE WRNGS WITH SMALL CRAFT ADVSYS
(THE EXCEPTION BEING THE COAST N OF PARRAMORE ISLAND WHERE BUOY
44009 LOOKS TO FLIRT WITH 35 KT GUSTS FOR A FEW MORE HRS).
OTHERWISE...TODAY WILL SEE WINDS SLOWLY VEERING FROM THE SW...TO THE
W BY AFTERNOON...WITH WIND SPEEDS DIMINISHING TO 15-20 KT FOR THE
MOST PART...ALLOWING SEAS THAT ARE CURRENTLY 7-11 FT TO DIMINISH TO
4-6 FT OR LESS. ON THE BAY THERE MAY BE ABOUT A 6 HR LULL IN THE
WINDS (GNLY TO 10-15 KT) LATER THIS AFTN/EARLY EVENING BEFORE THE
COLD SURGE. HAVE DECIDED TO SIMPLIFY THINGS AND CONTINUE THE SCA
HEADLINE THROUGH TONIGHT SINCE WINDS ARE EXPECTED TO INCREASE BACK
TO 15-20 KT DURING THE EVENING AS COLDER AIR ALOFT MOVES IN AND
MIXING BECOMES MORE EFFICIENT. ON THE COAST AND OVER THE SOUND HAVE
ENDED THE HEADLINES AT 23Z AS WINDS SHOULD REMAIN JUST BELOW SCA
THRESHOLDS. HIGH PRESSURE BUILDS IN FRI...OFFERING A BRIEF QUIET
PERIOD AHEAD OF THE NEXT SYSTEM WHICH WILL AFFECT THE REGION OVER
THE WEEKEND.
THIS SYSTEM WILL BE A COASTAL ONE...BRINGING A RAPID INCREASE IN NNE
FLOW ALLOWING FOR BUILDING SEAS ON SAT. ALTHOUGH THE MODELS DIFFER
SLIGHTLY ON TRACK AND STRENGTH...AT LEAST SCA CONDITIONS ARE
LIKELY...WITH GALES A GOOD POSSIBILITY. HAVE BUMPED UP SEAS A FEW
FEET FROM PREV FCST GIVEN THE MODEL CONTINUITY...SHOULD SEE ON THE
ORDER OF 7-10 FT ON THE COAST. TOO EARLY TO PREDICT TIDAL FLOODING
BUT ANOMALIES ON THE ORDER OF 1-2 FT WILL BE POSSIBLE.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EST FRIDAY FOR ANZ630>632.
SMALL CRAFT ADVISORY UNTIL 6 PM EST THIS EVENING FOR ANZ633-
654-656-658.
GALE WARNING UNTIL 7 AM EST THIS MORNING FOR ANZ650-652.
&&
$$
SYNOPSIS...SMF
NEAR TERM...SMF
SHORT TERM...MPR/SMF
LONG TERM...ESS
AVIATION...LKB
MARINE...LKB
