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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 092016
AFDLWX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
316 PM EST TUE FEB 9 2010

.SYNOPSIS...
LOW PRESSURE OVER THE GULF STATES WILL MOVE OFF THE CAROLINA COAST
TONIGHT AND INTENSIFY OFF THE DELMARVA OVERNIGHT. THIS WILL PROVIDE
ANOTHER ROUND OF WINTRY PRECIPITATION TO THE MID ATLANTIC REGION
TODAY THROUGH WEDNESDAY. HIGH PRESSURE RETURNS LATE IN THE WEEK.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
-- Changed Discussion --
STRONG UPPER-LEVEL LOW IN THE NORTHERN BRANCH OF THE JET IS ROTATING
THROUGH THE MIDWEST LATE THIS AFTERNOON WHILE LOW PRESSURE DEVELOPS
OFF THE MID-ATLANTIC COAST IN THE SOUTHERN BRANCH OF THE JET. AS THE
UPPER-LEVEL LOW MOVES INTO THE REGION TONIGHT...LOW PRESSURE WILL
RAPIDLY INTENSIFY ALONG THE MID-ATLANTIC COAST AS IT SLOWLY MOVES
NORTHWARD. THIS WILL SPREAD PRECIPITATION OVER THE REGION
TONIGHT...MAINLY IN THE FORM OF SNOW. THERE WILL BE ENOUGH WARM AIR
DRAWN INTO THE SYSTEM FOR A MIXTURE OF RAIN/SLEET AND SNOW...MAINLY
ACROSS LOWER SOUTHERN MARYLAND.

THE DRY SLOT WILL WORK ITS WAY INTO THE SOUTHERN PORTION OF THE CWA
TOWARD WEDNESDAY MORNING CAUSING ANY PRECIPITATION TO BE LIGHT.
HOWEVER...AS THE LOW CONTINUES TO RAPIDLY INTENSIFY WEDNESDAY
MORNING...THE DEFORMATION ZONE WILL SET UP OVER THE NORTHEASTERN
HALF OF THE CWA...BRINGING HEAVY SNOW TO THIS AREA. SNOW WILL SLOWLY
TAPER OFF WEDNESDAY AFTERNOON AS THE LOW PULLS AWAY. WILL CONTINUE
WITH THE WINTER STORM WARNING ACROSS OUR CWA WITH THE HIGHEST
AMOUNTS AROUND NORTH-CENTRAL MARYLAND INTO THE BALTIMORE
METROPOLITAN AREA. STRONG WINDS WILL ALSO DEVELOP WEDNESDAY AS THE
LOW INTENSIFIES. A WIND ADVISORY MAY BE WARRANTED ACROSS THE ENTIRE
CWA FOR WIND GUSTS UP TO 50 MPH. STRONG WINDS WILL COMBINE WITH SNOW
AND BLOWING SNOW TO PRODUCE NEAR BLIZZARD CONDITIONS...ESPECIALLY
FOR LOCATIONS NORTH AND EAST OF WASHINGTON DC.
-- End Changed Discussion --

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
-- Changed Discussion --
DP SFC LOW WL BE PULLING AWAY FM CWFA WED NGT...BUT THE WNDS WL BE
SLOW TO SUBSIDE AS THE P-GRAD REMAINS TIGHT. /GFS 00Z PROG 975 MB!/
THERE/S EASILY 35 KT W/IN MIXED LYR. GDNC SUGGESTS CLSR TO 40 KT...
BUT ALSO HINTS AT SFC BASED INVSN DVLPG. THAT REMAINS TO BE SEEN.
FCST WL ADVERTISE 20G35KT.

THERE MAY BE A FEW LINGERING SHSN WED NGT AS WELL...BUT THE BULK OF
THE ACCUM SNW WL BE DONE FOR MOST OF THE CWFA. THE XCPTN WL BE FOR
THE WRN UPSLP AREAS...WHERE CAA AND SNW GROWTH FVRBL...SPCLY WED
NGT. INVSN HGTS START TO DROP THU...BUT WONT BE TRULY LIMITED TIL
THU NGT-ELY FRI.

IT/LL STILL BE BRZY AND COLD E OF THE APPLCHNS THU-THU NGT...BUT
EFFECTS OF HIPRES SLOWLY WL BE REALIZED. COLD POOL ALOFT WL IMPEDE
NW FLOW IN SCOURING OUT CLDS...BUT THAT SHUD TAKE PLACE BY LT THU.
TEMPS WL BE WELL BLO AVG...MAXT IN THE MID 30S/MIN-T IN THE TEENS.
-- End Changed Discussion --

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
WKND STILL DOMINATED BY A STRONG SRN JET STREAM. ANY DISTURBANCES
SHUD BE SURPRESSED SUFFICIENTLY TO MISS CWFA. INSTEAD...WE WL BE
INFLUENCED BY SFC HIPRES. THAT SHUD PROVIDE WELCOMED DRY CONDS THRU
THE WKND. W/ NW FLOW AND A DEEP SNWPACK...DONT XPCT A SGFNT WARMUP
THO. TEMPS THRUT THE PD WL STRUGGLE TO REACH 40F...PRBLY TOPPING OUT
IN THE 30S.

CLIPPER SYSTEM PROGGED EITHER LT SUN OR ELY MON. ITS LOOKING WEAK
RIGHT NOW. IT REMAINS TO BE SEEN IF THOSE TRENDS WL CONT.
NONETHELESS...HV LEANED ON THE ELY SIDE /SUN/ IN PROGRESSIVE PTTN.
-- End Changed Discussion --

&&

.AVIATION /20Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
SNOW WILL OVERSPREAD THE TERMINALS LATE THIS AFTERNOON INTO EARLY
THIS EVENING. IFR/SUBIFR CIGS AND VSBYS ARE EXPECTED. SNOW WILL
CONTINUE THROUGH MOST OF THE DAY WEDNESDAY WITH CONTINUED IFR/SUBIFR
CIGS AND VSBYS. THE HEAVIEST SNOW WILL BE WEDNESDAY MORNING NEAR
KBWI AND KMTN.

NORTHWEST WINDS WILL BE SUSTAINED AROUND 15 TO 25 KNOTS WEDNESDAY
WITH GUSTS OVER 40 KNOTS.

ASIDE FM WNDS...THU WL BE VFR AS WELL. DO XPCT BKN CIGS...BUT
BASES SHUD BE ABV 3K FT. CLDS SHUD SCT OUT FRI-SAT. A CLIPPER WL
COME BY SUN. WL NEED TO WATCH IT...RIGHT NOW THINK MVFR
RESTRICTIONS PSBL.
-- End Changed Discussion --

&&

.MARINE...
-- Changed Discussion --
LOW PRESSURE WILL DEVELOP ALONG THE MID-ATLANTIC COAST TONIGHT. LOW
PRESSURE WILL RAPIDLY INTENSIFY WEDNESDAY...BRINGING WIND GUSTS OVER
40 KNOTS AT TIMES. A GALE WARNING REMAINS IN EFFECT WEDNESDAY. SNOW
TONIGHT AND WEDNESDAY WILL REDUCE VISIBILITY BELOW ONE HALF MILE AT
TIMES.

GLW XTNDD THRU THU AS 35 KT WELL W/IN REACH IN MIXED LYR. HIPRES
BLDS FRI...BUT SCA FLAGS MAY STILL LINGER. MORE TRANQUIL FOR THE
WKND.
-- End Changed Discussion --
&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...WINTER STORM WARNING UNTIL 7 PM EST WEDNESDAY FOR DCZ001.
MD...WINTER STORM WARNING UNTIL 7 PM EST WEDNESDAY FOR MDZ003>007-
     009>011-013-014-016>018-501.
     WINTER STORM WARNING UNTIL 4 PM EST WEDNESDAY FOR MDZ502.
VA...WINTER STORM WARNING UNTIL 7 PM EST WEDNESDAY FOR VAZ021-030-
     031-040-042-050>057-501-502.
     WINTER STORM WARNING UNTIL 4 PM EST WEDNESDAY FOR VAZ025>029-
     036>039.
WV...WINTER STORM WARNING UNTIL 7 PM EST WEDNESDAY FOR WVZ052>054-
     501-503.
     WINTER STORM WARNING UNTIL 4 PM EST WEDNESDAY FOR WVZ050-051-
     055-502-504.
MARINE...GALE WARNING FROM 8 AM WEDNESDAY TO 6 PM EST THURSDAY FOR
     ANZ530>543.
-- End Changed Discussion --

&&

$$
SYNOPSIS...BJL
NEAR TERM...BJL
SHORT TERM...HTS
LONG TERM...HTS
AVIATION...BJL/HTS
MARINE...BJL/HTS