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Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
355 am EST Tuesday Jan 27 2015

Synopsis...
strong low pressure will continue to track northeast off the New
England coast through tonight. High pressure will build overhead
Wednesday before a clipper system passes through later Thursday
into Thursday night. High pressure will return for Friday into
Saturday. Low pressure may impact the area by Sunday.

&&

Near term /through tonight/...
intense coastal low pressure system will continue to pull away from
the middle Atlantic region today. Bands of light snow will continue
to impact areas mainly to the east of the Blue Ridge mountains.
Energy from a negative tilt upper trough to the west will keep light
snow bands going for a few more hours and will produce an additional
half inch to one inch of snow in spots. Will keep all warnings and
advisories in place early this morning. Falling snow and sub
freezing temperatures will create slippery travel. The upper trough
and associated energy will pull into southern New England later
today with any light snow showers or flurries coming to an end. A
few light snow showers will hang on over the western slopes of the
Allegheny Front but should not amount to very much during today.

Gusty northwest winds and cold temperatures will follow for today.
Winds will average 15 to 20 miles per hour with gusts of 20 to 25
miles per hour...slightly higher over the ridgetops. This combined with high
temperatures struggling to reach the upper 20s to middle 30s will
create wind chill values in the teens and 20s in most locations.

A cold airmass will settle over the region tonight. Overnight lows
will fall back into the single digits out west to the teens to lower
20s east. Breezy northwest winds will reduce wind chills into the
single digits overnight.

&&

Short term /Wednesday through Wednesday night/...
high pressure will build into the middle Atlantic region on
Wednesday bringing a return to sunshine and less wind. Temperature
will be slow to rise as cold air remains in place. Afternoon high
temperatures will only reach the upper 20s over the north and west
to the middle and upper 30s east.

High pressure will build overhead Wednesday night...bringing dry
and cold conditions. Went a few degrees below guidance with the
min temperatures due to radiational cooling with dry conditions and light
winds. Min temperatures will range from the single digits and lower teens
across northern Maryland...to the lower and middle 20s in
Washington and Baltimore.

&&

Long term /Thursday through Monday/...
high pressure will move off the coast Thursday morning. A clipper
system will move into the area Thursday afternoon before passing
through Thursday evening. A period of wintry precipitation is
possible during this time. High pressure will build toward the
region Friday. Gusty northwest winds are expected ahead of this
system and it will be quite cold. High pressure will build
overhead Friday night and Saturday. Winds will gradually diminish
but it will remain cold.

Low pressure may impact the area Sunday and Monday...bringing a
chance for wintry precipitation. Details are highly uncertain this
far out.

&&

Aviation /08z Tuesday through Saturday/...
MVFR to locally IFR conditions will persist in low ceilings and visibility
restrictions due to snow bands. Ceilings and visibilities will lift to VFR
later today as low pressure pulls away from the region. VFR
conditions are expected tonight and Wednesday.

VFR conditions are expected Wednesday night through Thursday
morning. A clipper system may bring some wintry precipitation and
subvfr conditions Thursday afternoon into Thursday evening. Gusty
northwest winds are expected behind this system Friday...but high
pressure will build overhead Friday night into Saturday.

&&

Marine...
winds have not increased much overnight and therefore have cancelled
the Gale Warning and replaced it with a Small Craft Advisory for
today. Wind gusts on the waters will reach 25 to 30 kts as low
pressure pulls away to the northeast and high pressure builds toward
the middle Atlantic. The gradient will be slow to relax and Small Craft Advisory
conditions will be possible into early Wednesday.

High pressure will build over the waters Wednesday night. A clipper
system will pass through the waters later Thursday into Thursday
night. A Small Craft Advisory may be needed for portions of the
waters during this time. High pressure will build toward the
waters Friday.

High pressure will build toward the waters Friday...but gusty
northwest winds are expected ahead of this system. A Small Craft
Advisory will likely be needed and a Gale Warning may be needed
for portions of the waters during this time. Gusty winds will
continue into Friday. Gusty winds will continue into Friday night
before high pressure builds overhead Saturday.

&&

Lwx watches/warnings/advisories...
District of Columbia...Winter Weather Advisory until 10 am EST this morning for
dcz001.
Maryland...Winter Weather Advisory until 7 am EST this morning for mdz003-
502.
Winter Weather Advisory until 10 am EST this morning for
mdz004>006-011-013-014-016>018-503>508.
Winter Storm Warning until 7 am EST this morning for mdz501.
Virginia...Winter Weather Advisory until 7 am EST this morning for vaz028-
031-503-504.
Winter Weather Advisory until 10 am EST this morning for
vaz052>057-505-506.
WV...Winter Weather Advisory until 7 am EST this morning for
wvz050>053-055-502-504>506.
Winter Storm Warning until 7 am EST this morning for wvz501-
503.
Marine...Small Craft Advisory from 7 am this morning to 6 am EST
Wednesday for anz530>534-537>543.
Gale Warning until 7 am EST this morning for anz530>534-
537>543.
Small Craft Advisory until 6 am EST Wednesday for anz535-536.

&&

$$
Synopsis...bjl
near term...krw
short term...bjl/krw
long term...bjl
aviation...bjl/krw
marine...bjl/krw

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