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Area forecast discussion 
National Weather Service Baltimore Maryland/Washington District of Columbia
402 am EST sun Feb 14 2016

Synopsis...Arctic high pressure will hold through this evening
before moving offshore late tonight. Low pressure will impact the
region Monday through Tuesday bringing significant wintry
precipitation. High pressure builds for the middle and latter part
of the week.

&&

Near term /through tonight/...high pressure is moving overhead this
morning and winds are subsiding. Cold temperatures remain and
wind chill values range from -5 to 5 across much of the region
with the exception of the higher elevations where -10 to -15 are
being reached.

High pressure will persist across the region today and mostly sunny
conditions are expected. Temperatures will only climb into the 20s and
teens in the mountains today. High pressure slowly moves offshore tonight
and a light southerly wind will begin into Monday morning.

&&

Short term /Monday through Tuesday/...low pressure is expected to
develop across the Mississippi Valley tonight and a warm front
aloft will approach from the south into Monday morning. Strong
warm air advection aloft will lead to snow after midnight across
the southwest. Snow will move north and east into Monday morning
as warm air advection continues and should be light to moderate
across the region. Forecast soundings show warm air advection causing temperatures aloft to
become above freezing as early as Monday afternoon and therefore
snow is expected to change to sleet from southeast to northwest
into Monday evening. Surface temperatures will only rise to around 30 degrees
Monday afternoon before staying steady into Monday night. The surface
warm front will have a hard time moving northward Monday night
into Tuesday even though GFS/European model (ecmwf) have it crossing the region.
The Wedge of high pressure in place and light boundary layer winds
seem to hang on to the cold air much longer than low resolution
models portray. Based on climatology kept temperatures cooler than
guidance.

Any snow and sleet will transition to freezing rain Monday night as
warm air advection continues and the warm nose aloft lowers to the surface. Low
pressure will move into the Ohio Valley late Monday night and with
it...a slug of moisture is expected to move from west to east across
the middle-Atlantic region into Tuesday morning. The warm front will
likely move slowly into the region from the southeast and temperatures will
begin to go above freezing during the day Tuesday. Temperatures at higher
elevations will also become above freezing by Tuesday morning. The
warm front will likely reach northern Maryland and the Potomac Highlands by
late Tuesday morning into the afternoon. The combination of snow and
ice will lead to treacherous travel conditions for areas along and
west of the Blue Ridge mountains and therefore a Winter Storm Warning was
issued. Ice and snow conditions for this area of concern include
0.25 inch of ice accumulation on top of multiple inches of snow.
Snowfall accumulation will range from 4-8 inches across the SW County Warning Area
to 3-6 along and west of the Blue Ridge mountains further east...the
potential for 1-3 inches of snow and a tenth of an inch of ice is
forecast.

Low pressure rapidly moves into New York state Tuesday afternoon and
precipitation should end with the exception of a few rain or snow
showers along the western slopes of the mountains

&&

Long term /Tuesday night through Saturday/...mainly dry weather
through the end of the week as high pressure builds. Some upslope
precipitation will continue through Wednesday in the Potomac Highlands then
drying. Cooler weather returns Tuesday night through Thursday then warming up
for next weekend as high pressure slides offshore and winds turn more
southwesterly.

&&

Aviation /09z Sunday through Thursday/... VFR conditions expected today
into tonight as high pressure is overhead. Snow is expected to
move into the region from SW to NE late tonight and continue
Monday. Ceiling and visibility restrictions are expected due to snow. Winds
will stay under 10 kts and should not pose a threat to blsn.

Snow transitions to pl/freezing rain Monday afternoon into Tuesday morning.
Precipitation may be heavy at times and flight restrictions are expected.

Improving conditions Tuesday night through the end of the week.

&&

Marine...high pressure will build over the waters tonight. A Small Craft
Advisory is still in effect...but winds will continue to diminish
into tonight. Low pressure will likely impact the waters later
Monday into Tuesday.

No marine hazards expected Tuesday night and Wednesday.

Small craft conditions likely through Thursday.

&&

Tides/coastal flooding...blowout tides occurring at this time.
Winds diminish tonight with tides returning to normal. Strong srly
surge expected Monday night with water levels rising. Minor coastal
flooding possible at sensitive locations Tuesday.

&&

Lwx watches/warnings/advisories...
District of Columbia...Wind Chill Advisory until 9 am EST this morning for dcz001.
Maryland...Wind Chill Advisory until 9 am EST this morning for mdz003>006-
011-013-014-016>018-501>508.
Winter Storm Warning from 1 am Monday to 10 am EST Tuesday for
mdz003-004-501-502.
Winter Storm Watch from late tonight through Tuesday morning
for mdz005-503>505.
Virginia...Winter Storm Warning from 9 PM this evening to 10 am EST
Tuesday for vaz025>027-029-030-036-037-503-504-507-508.
Wind Chill Advisory until 9 am EST this morning for vaz025>031-
036>040-050>057-501>508.
Winter Storm Warning from 1 am Monday to 10 am EST Tuesday for
vaz028-031-038>040-501-505.
Winter Storm Watch from late tonight through Tuesday morning
for vaz050>053-055-056-502-506.
WV...Winter Storm Warning from 9 PM this evening to 10 am EST
Tuesday for wvz055-501-502-505-506.
Wind Chill Advisory until 9 am EST this morning for wvz050>053-
055-501>506.
Winter Storm Warning from 1 am Monday to 10 am EST Tuesday for
wvz050>053-503-504.
Marine...Small Craft Advisory until 1 PM EST this afternoon for
anz530>543.
Freezing spray advisory until 1 PM EST this afternoon for
anz530>543.

&&

$$
Synopsis...lfr
near term...has
short term...has
long term...lfr
aviation...has/lfr
marine...has/lfr
tides/coastal flooding...lfr

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