FXUS61 KAKQ 192029
AFDAKQ

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
329 PM EST THU NOV 19 2009

.SYNOPSIS...
A LOW PRESSURE SYSTEM AND ASSOCIATED FRONT MOVE THROUGH THE REGION
TONIGHT WITH SCATTERED SHOWERS. HIGH PRESSURE BUILDS INTO THE AREA
ON FRIDAY WITH DRY WEATHER EXPECTED THROUGH SATURDAY NIGHT. THE
NEXT STORM SYSTEM ARRIVES ON SUNDAY...WITH LOW PRESSURE MOVING UP
THE EASTERN SEABOARD MONDAY. ANOTHER COLD FRONT SWEEPS ACROSS
TUESDAY NIGHT INTO WEDNESDAY WITH DRY WEATHER FOR THANKSGIVING.

&&

.NEAR TERM /THROUGH FRIDAY/...
THE FRONTAL BOUNDARY WILL SLOWLY MOVE ACROSS REGION
TONIGHT...EXITING THE COASTAL ZONES BY MID MORNING FRIDAY. BUT THE
DEEPER MOISTURE AND DYNAMICS CONTINUE TO LIFT NE INTO CENTRAL PA
AS THE UPPER LOW LIFTS INTO GREAT LAKES AND THEN THE NORTHEAST.
WITH THIS PATTERN...THE CHANCES FOR SHOWERS SEEM TO BE
DIMINISHING. HAVE LEFT CHANCE POPS FOR THIS EVENING WITH THE FRONT
AS A SCATTERED SHOWERS COULD STILL DEVELOP...ESPECIALLY WITH THE
ADDITIONAL HEATING THAT HAS OCCURRED AHEAD OF THE FRONT. THE SKY
COVER HAS BROKEN SOME IN ADVANCE OF THE FRONT AND ONCE THE FRONT
PASSES...THE FLOW TURNS WESTERLY AND DRIES OUT. THIS SHOULD ALLOW
FOR RAPID CLEARING LATE TONIGHT AND FRIDAY. HIGH PRESSURE...WITH
ABUNDANT SUNSHINE IS EXPECTED FRIDAY.

FOR TEMPERATURES...LEANED TOWARD THE WARMER MAV GUIDANCE TONIGHT
AS THE MET SEEMS TOO COOL. EVEN WITH THE CLEARING SKY...THE COLD
AIR SEEMS TO BE DELAY BEHIND THE FRONT AS EVIDENCE BY THE 850 MB
TEMPS STILL 6C TO 10C FRIDAY. THIS COMBINED WITH SOME WINDS THIS
SHOULD KEEP THE READINGS UP SOME. ON FRIDAY...WITH THE SUN
RETURNING AND THE DOWN SLOPE FLOW...SHOULD SEE GOOD MIXING. WITH
THE 850 MB TEMPS IN THE 6C TO 10 C RANGE...WOULD EXPECT TEMPS IN
THE MID 60S TO LOWER 70S. GUIDANCE WAS NOT THAT HIGH HOWEVER...SO
HAVE LEANED TOWARD THE MAV NUMBERS WHICH WERE CLOSE. THE MET LOOKS
TOO COOL AGAIN.

&&

.SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/...
ON FRIDAY NIGHT...WITH THE HIGH SETTLING OVER THE AREA AND THE
THERMAL TROUGH SLIDING OVERHEAD...SHOULD SEE GOOD RADIATIVE
CONDITIONS. IT IS POSSIBLE THAT A FROST ADVISORY MAYBE NEEDED ON
FRIDAY NIGHT IN THE WESTERN PART OF THE CWA. TEMPERATURES SHOULD
DROP DOWN INTO THE MID 30S WEST AND AROUND 40 IN THE EAST.

THE HIGH PRESSURE MAINTAINS CONTROL ACROSS THE REGION THROUGH
SATURDAY NIGHT WITH DRY WEATHER AND ONLY SOME HIGH CLOUDS SWINGING
THROUGH THE AREA. TEMPERATURES SHOULD BE COOLER ON SATURDAY THAN
FRIDAY SO HAVE BLENDED BETWEEN THE MET AND MAV. BY SATURDAY
NIGHT...THE CLOUDS WILL BE ON THE INCREASE SO DESPITE THE LIGHT
WINDS...TEMPERATURES SHOULD NOT BE A COOL SATURDAY NIGHT SO HAVE
LEANED TOWARD THE MAV GUIDANCE.

BY SUNDAY...THE NEXT STORM SYSTEM WILL BEGIN TO APPROACH. THE NAM
AND GFS BOTH NOW SHOW THAT THE UPPER TROUGH AND CLOSED LOW WILL
LIFT MORE NE FROM THE LOWER MISSISSIPPI RIVER VALLEY INTO THE
OHIO VALLEY ON SUNDAY NIGHT. WHILE THE MODELS DO NOT SHOW THE BULK
OF THE RAIN GETTING IN UNTIL SUNDAY NIGHT...THEY ARE TYPICALLY TOO
SLOW WHEN IT COMES TO WARM ADVECTION PCPN. SO DID RAMP UP THE POPS
SUNDAY AFTERNOON. THE ONE ITEM TO WATCH WILL BE HOW FAR WEST THE
CLOSED LOW TRACKS. THE MODELS ARE NOTORIOUS FOR TRENDING WEST WITH
TIME WITH THESE TYPES OF SYSTEMS. A FURTHER WEST TRACK COULD
SIGNIFICANTLY DELAY THE ONSET OF POPS. FOR TEMPERATURES...DID LEAN
A LITTLE ABOVE THE LATEST MEX GUIDANCE...BASED ON THE UNCERTAINTY
OF THE TIMING OF THE PCPN AND CLOUDS.

&&

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
12Z MDL RUNS ARE HAVING A DIFFICULT TIME IN PARSING THE SYSTEM 
PROGGED TO AFFECT OUR FORECAST AREA ON SUN. EARLY IN THE WEEKEND, AN 
UPR TROF DIGS ACROSS THE US...PICKING UP SRN STREAM ENERGY FROM THE 
GOM...AND HELPING SUPPORT THIS SYS BY MVING IT NEWRD FROM THE GOM. 
THE GFS...WHICH UP TILL THE 06 RUN HAD BEEN SHOWING THIS LOW 
DEVELOPING OFF THE SE COAST THESE PAST FEW DAYS, IS SHOWING A SPLIT 
FLOW...WITH ONE LOW TRACKING WRD TOWARD THE OH VALLEY AND ANOTHER 
LOW MVING ACROSS THE FORECAST AREA. THE NAM WHICH SEEMS TO FOLLOW 
THE GFS TRENDS THESE PAST FEW WEEKS, IS ALSO SHOWING A SIMILAR WRN 
TRACK/SPLIT FLOW SOLN. THE EURO AND GEM ARE NOW THE MOST CONSISTENT 
MDLS...AS THEY CONTINUE TO SHOW THE LOW MVING NE ALONG THE SE COAST 
THRU EARLY NEXT WEEK.  

NO MATTER WHICH MDL YOU LEAN TOWARD, THE AREA WILL LIKELY SEE PRECIP 
ON SUN/SUN NIGHT. HOWEVER, IF THE GFS AND NAM ARE ONTO A NEW 
TREND...AND THE SPLIT FLOW CONTINUES SO THAT ONE LOW MVS TOWARD THE 
OH VALLEY AND THE OTHER BEGIN DEVELOPING MORE OFF THE
COAST...THERE IS A POSSIBILITY A GOOD CHUNK OF THE INTERIOR CWA
MAY NOT SEE AS MUCH PRECIP..BUT THAT'S ONLY IF THIS TREND
CONTINUES. FOR NOW, SW UPR FLOW WOULD NOT SUPPORT THIS OCCURING.
WILL HAVE TO WAIT FOR SUBSEQUENT MDL RUNS AND SEE HOW THIS PATTERN
EVOLVES. FOR NOW WILL STICK WITH 60% POPS...THOUGH CONFIDENCE IS
LESS THAN NORMAL ATTM. IT STILL LOOKS LIKE IF WE DO SEE RAIN THE
BEST CHC WILL STILL BE SUN/SUN NIGHT.

FORECAST CONFIDENCE CONTINUES TO BE LOW THRU NEXT WED AS WEAK SFC 
HIGH PRES BUILDS BRIEFLY BACK ACROSS THE AREA MON NIGHT INTO TUE. 
ANOTHER UPR LOW DIGS ACROSS THE US EARLY NEXT WEEK...POSSIBLY 
PUSHING A COLD FRONT INTO THE AREA BY MIDWEEK. HV INCLUDED SLIGHT 
CHC SHOWRS FOR TUE NIGHT INTO WED...BUT THE TIMING OF THIS FRONT 
VARIES CONSIDERABLY ATTM. TEMPS THRU THE EXTENDED GENERALLY 
CHARACTERIZED ARND SEASONABLY NORM.  

&&

.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
LATEST RADAR IMAGERY SHOWS SCT SHWRS N OF RIC AND ALONG THE
DELMARVA PENINSULA EARLY THIS AFTN. THESE SHWRS ARE ASSOCIATED
WITH AN UPR LVL SHORT WV AND WL MV TO THE N AND NOT REALLY AFFECT
THE TAF SITES. OTHERWISE...LITTLE IN THE WAY OF A FORCING
MECHANISM AS THE FNTL BNDRY REMAINS OVER THE APPALACHIANS. THE
FRNT WL MV E THIS EVNG AND PROVIDE ENOUGH LIFT TO PRODUCE SOME SCT
SHWRS ACRS THE RGN AS IT MVS THROUGH. MAINLY VFR/MVFR CONDS WL
CONTINUE THROUGH THE REST OF THE AFTN BEFORE CIGS BEGIN TO LWR AS
FNTL BNDRY APPROACHES. EXPECT MVFR/IFR OVERNIGHT CAUSED BY LOW
CIGS AHEAD OF THE FNT AND PATCHY FOG DVLPG BEHIND IT.

HI PRES BEGINS TO BLD INTO THE RGN FRI AFTN WITH VFR CONDS THROUGH
SAT. MDLS CONTINUE TO DIFFER ON LOCATION AND INTENSITY OF NEXT
SYSTEM WHICH LOOKS TO AFFECT THE REGION SUN INTO MON.

&&

.MARINE...
SEAS CONTINUE TO RUN AOA 5 FT...AND WILL CONTINUE THRU AT LEAST 
EARLY FRI AFTN. SCA FOR THE COASTAL WATERS REMAINS IN EFFECT. MADE A 
MINOR TWEAK TO THE NRN COASTAL WATERS...BASICALLY EXTENDED THE SMALL 
CRAFT HEADLINE THRU TOMORROW AFTN. 

WEAK FRONT MAKES IT ACROSS THE WATER TONIGHT. WATERS SHOULD SEE A 
BRIEF CAA SURGE IN WINDS BY FRI MORNING...15 TO 20 KT ON CHES 
BAY...SO WENT AHEAD AND ISSUED A SCA HEADLINE FOR HERE FOR A 6 HR 
PERIOD BEGINNING FRI MORNING UNTIL 1 PM. 

OTHERWISE...WATER WILL BE GENERALLY QUIET (EXCEPT FOR THE FAR SRN 
COASTAL WTERS WHERE 5 FT SEAS MAY LINGER) INTO EARLY THIS WEEKEND. 
NEXT EVENT COMES SUN AS A SYS (WHICH ORGINATES FROM THE GOM) LIFTS 
NE AND ACROSS THE MID ATLC. THERE IS SOME DISCREPENCY AS TO THE 
EXACT TRACK THIS SYS WILL TAKE...HALF THE MDLS TAKE A MORE ERLY 
COASTAL TRACK, AND THE OTHERS SPLIT THE SYS TOWARD THE OH VALLEY. AT 
THE VERY LEAST...IT APPEARS SCA CONDS WILL BE POSSIBLE FOR EARLY 
NEXT WEEK. POSSIBLY LOW-END GALE GUSTS...BUT THAT IS REALLY TOO 
EARLY TO SAY WITH THE LACK OF CONSISTENCY AT THIS TIME. 

&&

.HYDROLOGY...
RIVER FLOODING CONTS ACROSS THE CHOWAN BASIN DUE TO THE RECENT HVY
RAINFALL. SEE WBCFLSAKQ FOR MORE SITE SPECIFIC INFORMATION.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...SMALL CRAFT ADVISORY FROM 6 AM TO 1 PM EST FRIDAY FOR 
     ANZ630>632.
     SMALL CRAFT ADVISORY UNTIL 6 PM EST FRIDAY FOR ANZ650-652-654-
     656.
     SMALL CRAFT ADVISORY UNTIL 5 AM EST SATURDAY FOR ANZ658.

&&

$$
SYNOPSIS...ESS
NEAR TERM...ESS
SHORT TERM...ESS
LONG TERM...SMF
AVIATION...AM
MARINE...SMF
HYDROLOGY...