Area Forecast Discussion
Issued by NWS Sterling, VA

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FXUS61 KLWX 152004

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
304 PM EST Thu Feb 15 2018

.SYNOPSIS...A cold front will cross the area early on Friday.
High pressure will build north of the area Friday night. Low
pressure will then pass to the south Saturday night. High
pressure will return for early next week before another frontal
system affects the area mid next week.



Deep moisture with PWs 1-1.25 inches will continue to advect
ewd from the OH valley into our area tonight with showers
expected to develop ahead/along an approaching sharp cold front.
Rainfall amounts will range between 0.25 inches in the
southeast to one inch in the far NW corner. The front will
become fairly progressive which should limit rainfall totals. No
flooding is anticipated anywhere. Cdfnt will cross the area
around 09Z and push south of the area by 15Z.



Showers will end gradually from north to south on Fri with gusty
NW winds drying out things rapidly. Temps will begin to fall
rapidly after 10AM from the upper 50s in the morning to the
upper 40s by sunset. Cold Fri night under building high pressure
to the north.

Moisture will then begin to spread northeastward Sat morning as
coastal low develops offshore the mid-Atlc coast. Snow is
expected at onset late Sat morning in the southwest but with a
quick transition to snow/sleet mix late Sat and Sat evening.
This is a very quick moving system with precip duration only
about 6 hrs. No freezing rain is anticipated due to sfc temps
generally abv freezing. Snow to liquid ratios will be generally
around 5 to 1 or less in where sleet mixes in and between 7 to
10 along the Mason Dixon line where precip remains as snow
through the event. Snow amts of an inch or less are expected
south of I-70 with 1-2 inches north of there and nothing south
of I-64. Precip ends by midnight Sat night.



High pressure builds overhead on Sunday bringing dry conditions
over our region into Sunday night as southerly flow settles in.
A low pressure system moving towards the Great Lakes will push
a warm front over or nearby on Monday that could bring unsettled
weather over our area. A cold front will then stall to our
northwest Tuesday into Wednesday and keeping southerly flow over
us. Depending on how close it stalls, we could experience some
precipitation. The front will then slowly move across on
Thursday keeping the chance of precip over our CWA.

A warming trend will be in place in the long term period as high
temperatures will be gradually increasing from the 40s and 50s on
Sunday into near the 70s Tuesday and Wednesday. High temperatures
will drop around 10 degrees on Thursday due to the front.



Showers expected tonight as cdfnt crosses the area with brief
cigs restrictions into MVFR category. Wind shift expected
around 09Z with gusts around 20 kt expected.

Snow expected late Sat at onset with a quick transition to
snow/sleet mix Sat evening with precip ending by midnight Sat
night. Flight restrictions are likely late Sat and Sat evening.

VFR conditions are expected during on Sunday as high pressure
builds overhead. Periods of sub-VFR conditions possible Monday
into Tuesday as frontal boundaries affect our area, but it will
depend on how close they move.



Winds expected to strengthen late tonight into Fri with SCA
conditions expected. Winds should drop off below SCA Sat and
remain so through early next week.

Winds are expected to remain below SCA criteria from Sunday
into Monday night, therefore no small craft advisory expected
these days. Winds will increase later on Tuesday, which will be
monitored in case a SCA is required.


MARINE...Small Craft Advisory until 7 PM EST Friday for ANZ530>543.


MARINE...IMR/LFR is the U.S. government's official web portal to all federal, state and local government web resources and services.