FXUS61 KLWX 252017
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
317 PM EST WED NOV 25 2009

.SYNOPSIS...
A WEAK COLD FRONT WILL MOVE ACROSS THE MID ATLANTIC THIS EVENING. 
LOW PRESSURE WILL FORM OFF THE FLORIDA COAST TONIGHT...AND MOVE 
UP THE EASTERN SEABOARD THANKSGIVING DAY. ANOTHER COLD FRONT WILL 
MOVE ACROSS THE MID ATLANTIC THURSDAY NIGHT. HIGH PRESSURE RETURNS 
FOR THE WEEKEND.
&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
SOME CHANGES WERE OCCURRING IN THE ATMOSPHERE THIS AFTERNOON. WEAK 
COLD FRONT WAS APPROACHING FROM THE WEST...AND LOW LEVEL WINDS WHICH 
HAVE FAVORED AN EASTERLY COMPONENT FOR THE LAST COUPLE OF DAYS WERE 
TURNING TO THE SOUTH/SOUTHWEST AHEAD OF THE FRONT. 

LAST VESTIGES OF DRIZZLE WERE MOVING NORTHEAST ACROSS NORTH/CENTRAL 
MARYLAND THIS AFTERNOON. THIS WILL LIFT NORTHEAST OF THE BAY IN THE 
21Z-22Z TIME FRAME. 

CEILINGS WERE ALSO RISING THIS AFTERNOON...AND SATELLITE IMAGERY 
EVEN INDICATED SOME BREAKS IN THE CLOUDS WORKING INTO THE 
HIGHLANDS/SHENANDOAH VALLEY AREA. CLOUDS MAY EVEN SCATTER FOR A TIME 
LATER ON THIS EVENING...BEFORE FILLING BACK IN OVERNIGHT.

WHILE ADDITIONAL DRIZZLE IS NOT EXPECTED OVERNIGHT...THERE IS THE 
POTENTIAL FOR FOG FORMATION WITH LOW LEVEL MOISTURE LINGERING 
UNDERNEATH THE INVERSION AND A WEAK GRADIENT/CALM WINDS BEHIND THE 
FRONTAL PASSAGE. SOME GUIDANCE FORECASTS VISIBILITIES LOWERING TO 
1/4 MILE. THIS MAY BE PLAUSIBLE IF WE ARE ABLE TO DEVELOP SOME 
BREAKS/SCATTERINGS IN THE CLOUD COVER LATER THIS EVENING. WOULD 
THINK THE MOST LIKELY AREA FOR THIS WOULD OCCUR ACROSS THE WASH/BALT 
CORRIDOR...BUT DO NOT HAVE ENOUGH CONFIDENCE AT THIS TIME TO ISSUE A 
DENSE FOG ADVISORY. FOG WILL BE INCLUDED IN HWO.   
&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH 6 PM THURSDAY/...
MORNING FOG WILL LINGER INTO EARLY THANKSGIVING MORNING...BUT WILL 
BREAK UP BY MID MORNING. NEXT FRONT WILL APPROACH FROM THE 
WEST...BRINGING SHOWER CHANCES ACROSS THE HIGHLANDS DURING THE 
AFTERNOON. 12Z GFS/NAM AND 09Z SREFS AGREE WITH KEEPING POPS OUT OF 
THE FORECAST EAST OF THE MTNS THROUGH THE AFTERNOON HOURS. 
&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
COLD FRONT WILL MOVE THROUGH THE CWFA LATER IN THE DAY ON 
THANKSGIVING. WINDS ARE EXPECTED TO SHIFT TO THE NW BEHIND THE 
BOUNDARY...BECOMING FAVORABLE FOR UPSLOPE SNOW SHOWERS ALONG THE 
WESTERN RIDGES OF THE ALLEGHENIES. THE UPSLOPE SNOW SHOWERS ARE 
EXPECTED TO LINGER THROUGH EARLY SATURDAY AS CONDITIONS REMAIN 
FAVORABLE...PRODUCING SEVERAL INCHES OF SNOW. HAVE ISSUED A WINTER 
STORM WATCH FOR EXTREME WESTERN ALLEGANY...GRANT AND MINERAL 
COUNTIES...AS SNOWFALL TOTALS COULD APPROACH WINTER STORM CRITERIA.

HIGH PRESSURE BEGINS TO BUILD IN FROM THE SW LATER ON SATURDAY...AND 
REMAINS IN CONTROL OF THE SENSIBLE WEATHER THROUGH THE REMAINDER OF 
THE WEEKEND. THE HIGH CENTER MOVES OFFSHORE ON MONDAY...AHEAD OF THE 
NEXT FRONTAL SYSTEM. THE FRONT MOVES THROUGH DURING THE MIDDLE OF 
NEXT WEEK.  

&&

.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
IFR CONDITIONS ARE LIKELY TO LINGER AT KBWI/KMTN THIS 
EVENING...WHILE KDCA/KIAD/KCHO/KMRB WILL EXPERIENCE IMPROVED 
/MVFR-VFR/ CONDITIONS. THIS MAY CHANGE HOWEVER AS ANY IMPROVEMENT 
MAY BE REPLACED BY IFR/LIFR CONDITIONS OVERNIGHT/EARLY THANKSGIVING 
MORNING AS FOG/STRATUS TRY TO FORM. GUIDANCE IS NOT IN AGREEMENT 
REGARDING THE MAGNITUDE OF THIS OCCURRING...BUT HAVE LEANED TOWARD 
THE MORE PESSIMISTIC OF SOLUTIONS IN THE 18Z TAF ISSUANCE GIVEN LOW 
LEVEL MOISTURE LINGERING AND A WEAK GRADIENT.  

SCATTERED TO ISOLATED SHOWERS WILL BE POSSIBLE THURSDAY NIGHT AND 
FRIDAY AS AN UPPER LEVEL DISTURBANCE MOVES THROUGH THE 
AREA...IMPACTING LOCAL VSBYS. ANY CIGS SHOULD REMAIN ABOVE 3 KFT. 
BREEZY CONDITIONS ARE EXPECTED ON FRIDAY...WITH GUSTS TO AROUND 25 
KT AT THE TERMINAL SITES. CIGS/VSBYS ARE EXPECTED FOR THE REMAINDER 
OF THE WEEKEND INTO EARLY NEXT WEEK. 
&&

.MARINE...
WINDS HAVE SHIFTED TO A SOUTH-SOUTHWEST DIRECTION ACROSS THE WATERS 
THIS AFTERNOON AND MAY BECOME NORTH LATE TONIGHT BEHIND A WEAK FRONT 
BEFORE TURNING TO THE NORTHEAST ON THANKSGIVING DAY. DURING THIS  
TIME...SPEEDS ARE FORECAST TO BE AOB 10 KT. 

NW WINDS WILL INCREASE BEHIND A COLD FRONT LATE THURSDAY INTO 
SATURDAY. SMALL CRAFT CONDITIONS ARE LIKELY FRIDAY INTO SATURDAY. 
WINDS MAY GUST TO NEAR 20 KT RIGHT ALONG AND JUST BEHIND THE FROPA 
LATE THURSDAY NIGHT...BUT NOT CONFIDENT THE DURATION OF GUSTS WILL 
BE MORE THAN A FEW HOURS. 
&&

.TIDES/COASTAL FLOODING...
WATER LEVELS WERE CONTINUING TO RUN A FOOT TO FOOT AND A HALF
ABOVE NORMAL THIS AFTERNOON. HOWEVER...GIVEN THE LOWER
ASTRONOMICAL TIDES...MINOR TIDAL FLOODING HAS NOT OCCURRED DURING
THE LAST COUPLE OF HIGH TIDE CYCLES NOR IS IT EXPECTED OVER THE
NEXT COUPLE. 

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY 
     EVENING FOR MDZ501.
VA...NONE.
WV...WINTER STORM WATCH FROM THURSDAY EVENING THROUGH FRIDAY 
     EVENING FOR WVZ501-503.
MARINE...NONE.

&&

$$
PELOQUIN/LISTEMAA