FXUS61 KLWX 291536 AAA
AFDLWX
AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1036 AM EST SUN NOV 29 2009
.SYNOPSIS...
HIGH PRESSURE WILL MOVE OFF THE EAST COAST THROUGH TONIGHT. A
COLD FRONT WILL PASS THROUGH MONDAY...BRINGING A GOOD CHANCE FOR
SHOWERS. HIGH PRESSURE WILL RETURN TUESDAY...BUT LOW PRESSURE WILL
IMPACT THE REGION WEDNESDAY INTO THURSDAY. CANADIAN HIGH PRESSURE
WILL BUILD OVERHEAD LATE IN THE WEEK.
&&
.NEAR TERM /UNTIL 8 PM THIS EVENING/...
CLEAR SKIES...LIGHT SWLY WINDS...TEMPS RISING INTO THE L-M60S FOR
A NICE TRANSITION DAY. A COMPLEX SERIES OF WX-FEATURES COMING
TOGETHER FROM THE GREAT LAKES TO THE PACIFIC COAST. AN APPROACHING
UPPER WAVE IS SLIDING DOWN THRU THE NRN PLAINS...PICKING UP
MOISTURE AHEAD OF IT /FROM LAKE MICHIGAN TO THE LOWER MISSISSIPPI
VLY. THIS IS ALSO AHEAD OF AN UPPER CUT-OFF LOW IVER SRN
CA /THAT WILL MAKE A TREK EWD ACROSS SRN PLAINS AND GULF COAST
EARLY IN THE WEEK/.
THE ERN EXTENT OF THE ACTIVITY ACROSS THE WRN OHIO VLY WILL BEGIN
TO PUSH HIGH-MID LEVEL CLOUDS INTO THE CNTRL APLCNS BY LATER THIS
EVENING.
&&
.SHORT TERM /8 PM THIS EVENING THROUGH 6 AM MONDAY/...
SFC LOPRES MOVES INTO NRN NEW ENGLAND BY LATE TNGT. BKN-OVC MID-
LVL CLDS WILL INCR QUICKLY THIS EVE. HAVE INCRD CLD CVR SLGTLY
FROM PREV FCST...WHICH DEPICTED TREND WELL BUT WAS NOT QUITE AS
AGGRESSIVE.
PCPN XPCD TO BE ONGOING ALONG CDFNT THIS EVE...PRIMARILY OHVLY AND
WRN WV. AS WAVE APRCHS...PCPN WILL SPREAD INTO WRN ZONES AS CDFNT
ARRIVAL FOSTERS UPSLP FLOW ALONG WRN SLOPES. HAVE INCRD POPS TO
LKLY LATE TNGT FOR WRN SLOPES OF ALLEGHENY FRONT. NEVERTHELESS...
PCPN AMOUNTS WILL BE LIGHT. LIGHT PCPN MAY BGN TO SPREAD ACRS NRN
MD AND WV PNHDL LATE TNGT.
COOLING TNGT WILL BE HAMPERED BY INCRG LOW-LVL CLDS AND HIGHER
MSTR CONTENT. THEREFORE...FCST MINIMA IN UPR 30S-MID 40S.
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
A COLD FRONT WILL PASS THROUGH THE REGION MONDAY. DESPITE LIMITED
MOISTURE WITH THIS SYSTEM...THERE WILL BE ENOUGH LIFT FOR SHOWERS
ALONG AND JUST BEHIND THE COLD FRONT. QPF AMOUNTS WILL BE AROUND
ONE TENTH OF AN INCH ACROSS THE NORTHERN AND EASTERN CWA...WITH
LIGHTER AMOUNTS ACROSS CENTRAL VIRGINIA. UPSLOPE SNOW SHOWERS
BEHIND THE FRONT WILL IMPACT THE POTOMAC HIGHLANDS MONDAY
AFTERNOON/NIGHT. LIGHT SNOW ACCUMULATIONS ARE POSSIBLE...ESPECIALLY
MONDAY NIGHT.
HIGH PRESSURE WILL BUILD OVER THE REGION TUESDAY...BRINGING DRY AND
SEASONABLE CONDITIONS. HIGH PRESSURE WILL MOVE OFF THE COAST
TUESDAY NIGHT INTO WEDNESDAY WHILE LOW PRESSURE TRACKS ALONG THE
GULF COAST. THIS LOW WILL TRACK UP THE TENNESSEE VALLEY WEDNESDAY
NIGHT BEFORE TRANSFERRING ITS ENERGY TO A SECONDARY LOW OFF THE
MID-ATLANTIC COAST. THIS SECONDARY LOW WILL TRACK TOWARD NEW
ENGLAND THURSDAY AS IT INTENSIFIES. DESPITE A LACK OF CERTAINTY IN
THE EXACT TRACK OF THIS SYSTEM...IT DOES APPEAR THAT CLOUDS AND
RAIN WILL OVERSPREAD THE REGION FROM SOUTH TO NORTH LATER
WEDNESDAY INTO WEDNESDAY NIGHT. RAIN WILL HANG AROUND OVERNIGHT
WEDNESDAY AND PROBABLY INTO THURSDAY BEFORE DRIER AIR MOVES INTO
THE REGION ON THE BACKSIDE OF THE LOW LATER THURSDAY/THURSDAY NIGHT.
COLDER AIR WILL WORK ITS WAY INTO THE REGION FRIDAY AND SATURDAY
BEHIND THE STORM SYSTEM AND AHEAD OF CANADIAN HIGH PRESSURE.
NORTHWEST FLOW WILL BRING UPSLOPE SNOW SHOWERS TO THE POTOMAC
HIGHLANDS DURING THIS TIME.
&&
.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
LIGHT WINDS WILL CONTINUE TO BECOME MORE SWLY THIS AFTN /ONLY IN
THE 5-10KT RANGE/. MOSTLY SUNNY SKIES THRU MUCH OF TDA WITH INCRG
CLDS LATE THIS AFTN. BKN-OVC SKIES INTO THE EVENING HRS WITH CIGS
AT 4.0 KFT XPCD LATE TNGT.
A COLD FRONT WILL PASS THROUGH THE TERMINALS MONDAY...BRINGING A
GOOD CHANCE FOR SHOWERS ALONG WITH SUBVFR VSBYS/CIGS. MAINLY MVFR
CONDITIONS ARE EXPECTED WITH THIS SYSTEM...BUT BRIEF PERIODS OF
IFR CIGS/VSBYS ARE POSSIBLE IN SHOWERS. THE BEST CHANCE FOR
SHOWERS WILL BE DURING THE MORNING AND MIDDAY HOURS. NORTHWEST
WIND GUSTS AROUND 20 KNOTS ARE EXPECTED BEHIND THE FRONT MONDAY
AFTERNOON INTO EARLY MONDAY EVENING.
HIGH PRESSURE WILL BRING VFR CONDITIONS MONDAY NIGHT THROUGH
TUESDAY. LOW PRESSURE WILL TRACK TOWARD THE TERMINALS WEDNESDAY...
BRINGING INCREASING CLOUDS ALONG WITH A CHANCE OF RAIN DURING THE
AFTERNOON. A SECONDARY LOW WILL DEVELOP OFF THE MID-ATLANTIC COAST
WEDNESDAY NIGHT BEFORE TRACKING TOWARD NEW ENGLAND THURSDAY. RAIN
WILL IMPACT THE TERMINALS WEDNESDAY NIGHT INTO THURSDAY. SUBVFR
CIGS AND VSBYS ARE EXPECTED DURING THIS TIME.
&&
.MARINE...
LIGHT WINDS ACRS CHSPK BAY AND TIDAL POTOMAC INTO THE AFTN. SLY
WINDS WILL INCREASE LATER THIS AFTN. GUSTS TO 20 KT WILL SPREAD
NWD TNGT INTO CNTRL PORTIONS OF THE MD CHSPK BAY AND LWR TIDAL
POTOMAC. SMALL CRAFT ADZY ISSUED TNGT FOR THESE ZONES.
A COLD FRONT WILL PASS THROUGH THE WATERS MONDAY. SCA WINDS ARE
EXPECTED AHEAD OF THE FRONT ACROSS THE MIDDLE PORTION OF THE BAY
AND LOWER TIDAL POTOMAC MONDAY MORNING...AND ACROSS ALL OF THE
WATERS MONDAY AFTERNOON INTO MONDAY EVENING. THE GRADIENT BEHIND
THE FRONT WILL REMAIN STRONG ENOUGH FOR SCA WIND GUSTS OVER THE
CHESAPEAKE BAY AND LOWER TIDAL POTOMAC MONDAY NIGHT.
SCA WINDS ARE POSSIBLE TUESDAY AHEAD OF APPROACHING HIGH PRESSURE
OVER THE CHESAPEAKE BAY AND LOWER TIDAL POTOMAC. WINDS WILL DIMINISH
TUESDAY NIGHT AS HIGH PRESSURE BUILDS OVERHEAD.
LOW PRESSURE WILL APPROACH THE WATERS WEDNESDAY BEFORE PASSING
THROUGH WEDNESDAY NIGHT AND EVENTUALLY HEADING TOWARD NEW ENGLAND
THURSDAY. SCA WINDS ARE LIKELY WEDNESDAY NIGHT INTO FRIDAY BEHIND
THE LOW.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY FROM NOON MONDAY TO 6 AM EST TUESDAY FOR
ANZ530-531-538-539.
SMALL CRAFT ADVISORY FROM 6 PM THIS EVENING TO 6 AM EST
TUESDAY FOR ANZ532>534-537-540>543.
SMALL CRAFT ADVISORY FROM NOON TO 8 PM EST MONDAY FOR ANZ535-
536.
&&
$$
UPDATE...GMS
PREV DISCUSSION...KRAMAR/LASORSA
