FXUS61 KAKQ 060309
AFDAKQ
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE WAKEFIELD VA
1009 PM EST SAT DEC 5 2009
.SYNOPSIS...
HIGH PRESSURE RETURNS TO THE AREA FROM LATE TONIGHT THROUGH
TUESDAY. THE NEXT STORM WILL DEVELOP OVER THE CENTRAL
PLAINS...THEN MOVE INTO THE EASTERN STATES BY WEDNESDAY.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
MSTR QUIKLY WINDING DN...WL HV GRDL CLRG OVRNGT AS COLDER AMS
SPRDS INTO THE RGN ON NWLY LLVL FLO. TEMPS FALLING INTO THE M/U20S
(WELL) INLAND...TO M30S NR THE SE CST.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH TUESDAY/...
HI PRES BUILDS OVR THE FA SUN...BRINGING DRY BUT RELATIVELY COLD
CNDTNS. HIGHS L/M 40S N...M/U 40S CNTRL AND SOUTH. CLDS FROM NXT
SRN STREAM S/W APPRCH ERY MONDAY...BUT NOT BEFORE A VERY COOL
NIGHT SUNDAY NIGHT. LOWS M20S- M30S.
MODELS DID INTRODUCE A LITTLE ADDITIONAL OVERRUNNING MOISTURE WITH
QUICK MOVING FRONTAL PASSAGE AND ASSOCIATED SOUTHERN STREAM
SHORTWV TROUGH MONDAY AFTN/EVENING...SO DID INCREASE CLDS AND
INSTALL A SLIGHT CHC POP DURING THIS TIMEFRAME. HIGHS M40S-L50S.
HIGH PRESSURE BUILDS BACK OVER THE REGION FOR TUESDAY. HIGHS
U40S/NR50 NORTHERN TIER...L50S SOUTH.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
MODELS CONTINUE THEIR TREND OF GOOD CONSISTENCY IN THE EXTENDED
RANGE AS THE STRONG SOUTHERN STREAM CONTINUES WITH SOME INTRUSIONS
FROM THE NORTHERN STREAM EXPECTED AS A STRONG CLOSED LOW DROPS
OVER THE NORTH POLE DROPS SOUTHWARD INTO CENTRAL CANADA LATE IN
THE PERIOD.
ON TUESDAY NIGHT INTO WEDNESDAY...THE MODELS CONTINUE TO BE IN
GOOD AGREEMENT SHOWING A STRONG WAVE EJECTING OUT OT THE
SOUTHWESTERN US AND AMPLIFYING OVER THE CENTRAL PLAINS AND LIFTING
INTO THE GREAT LAKES BY WED AFTERNOON. AHEAD OF THIS WAVE...GOOD
AMOUNT OF GULF MOISTURE WILL HEAD NORTHWARD...PROVIDING ANOTHER
SHOT OF MODERATE RAIN FOR THE EASTERN SEABOARD. AT THIS POINT...IT
SHOULD BE ALL RAIN...BUT WITH A WEDGE IN PLACE...WILL HAVE TO
MONITOR AS INITIAL RAIN COULD BE FALLING INTO A VERY DRY AIR
MASS...WHICH COULD LEAD TO SOME POTENTIAL WINTRY PCPN ALONG THE
BLUE RIDGE AND AREAS WEST. THE DRY SLOT SHOULD PUSH IN BY WED
AFTERNOON...CUTTING OFF ALL THE PCPN...ALLOWING FOR SOME
CLEARING. BUT THE COLD POLAR AIRMASS THAT GETS PULLED SOUTH WITH
THIS WAVE WILL NOT ARRIVE UNTIL THURSDAY WHEN THE SURFACE LOW
PULLS OFF THE COAST.
HIGH PRESSURE WITH THE COOLER AIR MASS HANGS AROUND THROUGH FRIDAY
AS HEIGHTS AGAIN BEGIN TO BUILD. BUT BY SATURDAY...THE ACTIVE
SOUTHERN STREAM ONCE AGAIN KICKS A WAVE EASTWARD FROM THE SOUTHERN
ROCKIES...TAPPING THE GULF AGAIN AND SENDS MORE MOISTURE INTO THE
SOUTHEASTERN AND MID ATLANTIC STATES.
FOR TEMPERATURES HAVE GENERALLY FOLLOWED ALONG WITH THE HPC
GUIDANCE...BUT DID ALLOW FOR MORE COOLING ON WED NIGHT THROUGH
THURSDAY NIGHT AS THE MOS GUIDANCE IS MUCH LOWER...WHICH IS
INDICATIVE OF THE COOLING SHOWN IN THE GFS.
&&
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
WIDESPREAD IFR CEILINGS COVER THE TAF SITES AND THIS WILL CONTINUE
THROUGH THE AFTN. COVERED 300 FT AT THE SE 3 TAF SITES. WINDS HAVE
VARIED SOMEWHAT IN DIRECTION BUT GENERALLY WINDS ARE OUT OF THE
NORTH.
FAIRLY STEADY RAIN IS ALSO OCCURRING. AS OF 18Z...PCPN CHANGES TO
SNOW A SHORT DISTANCE TO THE N AND W OF RIC AND TEMPERATURES SHOULD
COOL ENOUGH FOR A CHANGEOVER THERE TOWARD EVENING. THIS MAY OCCUR AT
SBY A LITTLE LATER BUT LTL OR NO SNOW IS EXPECTED AT THE OTHER TAF
SITES BEFORE THE PCPN ENDS.
DURING THE EVNG AND OVERNIGHT...THE COASTAL LOW THAT IS PRESENTLY
OFF THE NC COAST WILL PULL WELL TO THE NORTHEAST AND WINDS WILL
SHIFT TO NW ACROSS THE AREA. PCPN WILL END FROM SW TO NE AND
CEILINGS WILL CLIMB QUICKLY AND LATER CLEAR OFF. WINDS WILL DIMINISH
LATE TNGT TO LESS THAN 10 KNOTS ACROSS THE AREA BY SUN MRNG.
THERE WILL BE A SLIGHT CHC FOR PCPN IN THE ECG AREA MON. THE NEXT
WIDESPREAD PCPN EVENT WILL BE AROUND WED. IFR CONDITIONS CAN BE
EXPECTED.
&&
.MARINE...
LOW PRESSURE OFF THE COAST CONTINUES TO INTENSIFY AS THE STRONG
SHORTWAVE SLIDES OFF THE MID ATLANTIC COAST. AS THE LOW
STRENGTHENS...WILL SEE THE NE TO ENE FLOW STRENGTHEN TO 30 TO 35
KTS WITH GUST TO 40 KTS FOR A BRIEF PERIOD OF TIME FROM 00Z TO 6Z.
BUT WITH THE LOW QUICKLY RACING INTO THE CANADIAN MARITIMES...WILL
SEE WINDS DROP OFF AFTER 6Z...WITH A PERIOD OF SCA CONDITIONS
EXPECTED THROUGH ABOUT 16Z ON THE BAY AND LINGERING INTO THE
AFTERNOON BASED UPON THE SEAS...WHICH WILL RELAX DURING THE
AFTERNOON. HIGH PRESSURE BUILDS IN SUNDAY MORNING AND WILL LINGER
INTO THE DAY ON TUESDAY. A WEAK FRONT ALOFT MAY SLIDE ACROSS THE
AREA ON MONDAY EVENING...BUT WITH LITTLE WINDS...NOT ANTICIPATING
MUCH IMPACT ON MARINE CONDITIONS.
THE NEXT SYSTEM TO IMPACT THE REGION WILL COME TUESDAY NIGHT INTO
WED AS ANOTHER SOUTHERN STREAM LOW DEEPENS OVER THE SOUTHERN
PLAINS AND HEADS INTO THE GREAT LAKES. EAST TO SOUTHEAST WIND
SHOULD DEVELOP AHEAD OF THE SYSTEM WITH SCA TO GALE WINDS
POSSIBLE. THE COLD FRONT WILL SWEEP ACROSS WEDNESDAY EVENING WITH
THE FLOW TURNING NW...BUT SHOULD STILL BE GUSTY WITH STRONG COLD
ADVECTION EXPECTED THROUGH THURSDAY. HIGH PRESSURE RETURNS FRIDAY.
&&
.HYDROLOGY...
FLD WRNG HAS BEEN CANCELLED FOR NOTTOWAY RIVER NEAR STONY CREEK. DUE
TO RECENT HEAVY RAINFALL OVER THE REGION AND SLOW RISES...HV GONE W/
WRNG FOR SEBRELL STARTING MON MRNG...CONTG INTO MIDWEEK.
&&
.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...NONE.
NC...NONE.
VA...NONE.
MARINE...GALE WARNING UNTIL 3 AM EST SUNDAY FOR ANZ632-656-658.
SMALL CRAFT ADVISORY UNTIL NOON EST SUNDAY FOR ANZ630-631-633.
GALE WARNING UNTIL 5 AM EST SUNDAY FOR ANZ650-652-654.
&&
$$
SYNOPSIS...ALB/MAM
NEAR TERM...ALB/MAM
SHORT TERM...MAM
LONG TERM...ESS
AVIATION...LSA
MARINE...ESS
HYDROLOGY...AKQ
