FXUS61 KAKQ 240239
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
939 PM EST WED DEC 23 2009

.SYNOPSIS...
HIGH PRESSURE DOMINATES THE WEATHER ALONG THE EAST COAST THROUGH
CHRISTMAS EVE. STRONG LOW PRESSURE MOVES NORTHEAST INTO THE GREAT
LAKES REGION FRIDAY THROUGH SATURDAY. THE ASSOCIATED WARM FRONT
LIFTS NORTH OF THE AREA FRIDAY MORNING...WITH THE TRAILING COLD
FRONT CROSSING THE REGION SATURDAY MORNING. HIGH PRESSURE BUILDS
BACK INTO THE REGION FROM THE WEST SUNDAY INTO EARLY NEXT WEEK.

&&

.NEAR TERM /THROUGH THURSDAY/...
WATER VAPOR TONIGHT SHOW A LARGE CLOSED LOW OFF THE NEW ENGLAND
COAST...WHICH HAS PUSHED SOME VERY DRY AIR DOWN INTO MD AND NRN
VA...BUT NOT MUCH FURTHER SOUTH THAN FREDRICKSBURG. THIS FEATURE
IS STILL HELPING TO KEEP THE HIGHER CLOUDS SPREADING EAST FROM THE
LARGE SYSTEM OVER THE CENTRAL US FROM SPREADING EASTWARD INTO THE
REGION. AS A RESULT...HAVE REDUCED THE SKY COVER OVER MOST OF THE
AREA TONIGHT AND THURSDAY AS THE MODELS CONTINUE TO SHOW VERY
LITTLE MOISTURE MAKING IT INTO THE REGION. HAVE ALSO ADJUSTED THE
OVERNIGHT LOWS...RAISING THEM UP 2 TO 4 DEGREES FOR MANY SITES AS
THE DRY AIR AND LOWER DEW POINTS SHOULD REMAIN NORTH OF THE
AREA...AND BASED UPON THE LOWS FROM PREVIOUS NIGHTS...THE GUIDANCE
HAS BEEN RUNNING TOO COOL.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
MODELS CONT TO AGREE IN YET ANTHR POTENT SYSTM TO EFFECT THE RGN
FRI INTO SAT AM. STILL SOME TIMING DIFFERENCES WITH THE GFS BEING
A FEW HRS QUICKER IN MOVG PCPN INTO RGN. SREF A BLEND..SO LEANED
TOWARD ITS TIMING SOLN. AIRMASS INITIALLY DRY THU NITE AS FIRST
WAVE OF OVER RUNNING APPRCHS FROM THE SW. XPCT SOME COLUMN COOLING
ACROSS WRN CNTYS AFTR 06Z. CRITICAL THICKNESS VALUES SPRT THE PCPN
TO START OUT AS A LGHT FZ RAIN/SLEET MIX ACROSS WRN PIEDMONT
(CNTYS W OF I95). LOWS IN THE U20S-U30S. LTL OR NO ICE XPCTD ACCUM
XPCTD B4 12Z FRI. MINS MAY OCCUR EARLY THEN STDY OUT OR SLOWLY
RISE AS WAA KICKS IN DRNG PRE-DAWN HRS.

SCND WAVE OF MSTR OVRSPRDS RGN X-MAS DAY AS WRM FRNT LIFTS N OF RGN.
XCPTN BEING XTREME NW CNTYS WHERE LL WEDGE PROGGED TO HOLD ON THRU 
16Z. XPCT RAIN TO BECOME WDSPRD OVR THE FA SO INCRSD POPS TO
CATEGORICAL. SOME FZ RAIN PSBL AT THE ONSET OF PCPN (FIRST HOUR OR
TWO) NW OF A BOWLING GREEN-RICHMOND-FARMVILLE LINE. ONLY AREAS
THAT MIGHT GET A LIGHT ICE ACCUMULATION BEFORE THE CHANGEOVER TO
ALL RAIN WOULD BE OVR LOUISA/FLUVANNA/CUMBERLAND CNTYS WHERE A 4
TO 5 HR PRD OF MIXED PCPN XPCTD. TMPS TRICKY AS READINGS MAY STAY
WITHIN A DEGREE OR 2 OF 40 IVOF LKU BUT RANGE TO NR 60 AT ECG.

SCNDRY LOW DVLPS THEN MOVES N ALONG THE OCCLUDED FRNT FRI NITE/ERLY
SAT MORN. THIS KEEPS PCPN CHCS GOING THRU THE NITE. ISLTD THUNDER
PSBL TO THE S&E OF WHERE TRIPLE PT TRACKS...WHICH APPEARS TO BE
ALONG THE OUTER BANKS ATTM...SO WILL LEAVE THUNDER OUT OF FCST WITH
THIS PACKAGE. LOWS FROM THE U30S NW TO M50S (WRM SCTR) SE.

FRNT PUSHES E OF RGN SAT AM TAKING THE PCPN WITH IT. KEPT POPS SAT
AM BUT DROPPED POPS SAT AFTR. MILD WITH HIGHS 50-60. 

QPF WISE...AVG RAINFALL BTWN 1/2 TO 1 INCH XPCTD (LCLLY HIGHER AMTS
OF 1 TO 1.5 INCHES PSBL ACROSS THE PIEDMONT AND ALONG THE COAST IF
ANY CONVECTION DOES DVLP). THIS RAIN COMBINED WITH ANY SNOWMELT CUD
CERTAINLY LEAD TO MINOR FLOODING PTNTL COME FRI AFTRN/NIGHT. TO EARLY
FOR A WATCH ATTM...BUT WILL HIGHLIGHT IN HWO.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
NO REAL BIG FORECAST ISSUES FOR THIS PERIOD AS CAA SHOULD BE WELL 
UNDERWAY BEHIND AFOREMENTIONED SYSTEM. ECMWF DOES HINT AT SOME 
MOISTURE TRYING TO FILTER IN ON MONDAY. NOT ENOUGH EVIDENCE TO 
SUPPORT THAT SO WL LEAVE DRY IN DAYS 5 THROUGH 7 FOR RIGHT NOW. JUST 
LOOK TO HAVE BELOW NORMAL TEMPS FOR THE ENTIRE LATTER PERIODS AND 
DRY...OTHER THAN A FEW CLOUDS/FLURRIES POSSIBLE MONDAY INTO TUESDAY 
WITH VORT SWINGING ACRS THE AREA.

&&

.AVIATION /03Z THURSDAY THROUGH MONDAY/...
NO MAJOR CHANGES TO FCST AS HI PRES REMAINS OVER THE MID ATLANTIC
REGION TONIGHT. VFR CONDS AND MAINLY CALM WNDS WL CONTINUE
THROUGH 13Z THU. LGT NE WNDS WL RETURN THU MRNG WITH HI CLDS
BEGINNING TO SPREAD ACRS THE AREA EARLY IN THE AFTN. CLDS WL
THICKEN AND CIGS WL LWR DURING THE AFTN/EVE LATE AS WARM FRNT
MVS INTO AREA THU NITE INTO FRI...RA MVS IN FRI AM AND WE COULD
SEE IT BEGIN AS A MIX FZRA FOR A FEW HRS RIC AND WEST...RA AT
OTHER TAF SITES. MVFR/IFR CIGS/VSB LIKELY FRI AM INTO SAT. COLD
FRONT PUSHES THRU SAT WITH HIGH PRES AND VFR RETURING FOR THE
START OF THE WEEK.

&&

.MARINE...
THROUGH THE NEXT 24 HOURS SHOULD BE NO NEED FOR MARINE HEADLINES
ANY SURGES TONIGHT SHOULD NOT MAKE WINDS FREQUENTLY HIGH ENOUGH... 
SO NO FLAGS EXPECTED FOR TONIGHT. IN LOOKING FURTHER OUT MDLS SEEM 
TO BE IN AGREEMENT WITH INCRSING WINDS TO SCA BY FRIDAY EVENING. SO 
WL STICK WITH THAT TREND. THE COLD FRONT WL HAVE LINGERING AFFECTS 
THIS WEEKEND. WINDS WL TURN TO MORE EASTERLY LATE. BEGINNING FRIDAY 
SEAS WL ALSO BUILD AND LIKELY PEAK OUT BETWEEN 7 AND 9 FEET SOMETIME 
ON SATURDAY BEFORE GRADUALLY SUBSIDING. SOME RESIDUAL SWELL COULD BE 
SEEN INTO MONDAY.

&&

.EQUIPMENT...
PHONE SERVICE APPEARS TO HAVE BEEN RESTORED...RETURNING ALL NOAA ALL
HAZARDS/WEATHER RADIO TRANSMITTERS OPERATING OUT OF WFO WAKEFIELD
VA BACK TO SERVICE. PERIODIC OUTAGES MAY CONTINUE UNTIL PHONE
SERVICE HAS BEEN COMPLETELY RESTORED.

&&

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

&&

$$
SYNOPSIS...MPR
NEAR TERM...ESS
SHORT TERM...MPR
LONG TERM...KLL
AVIATION...AM/CY
MARINE...KLL
EQUIPMENT...