Area Forecast Discussion
Issued by NWS Sterling, VA
FXUS61 KLWX 151944
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
244 PM EST Wed Feb 15 2017
A cold front will pass through the region this morning. High
pressure builds overhead through Friday and then remains nearby
into early next week.
.NEAR TERM /THROUGH THURSDAY/...
A cold front has moved east of the I-95 corridor and gusty northwest
winds have begun. Isolated/scattered showers will continue this
afternoon as lapse rates steepen during peak heating. Temperatures
have risen into the mid 30s in the mtns to the mid 50s across I-95.
Snow showers are expected in the mtns and rain or snow showers
expected east. Visibilities may suddenly drop in snow showers
however sfc temperatures will result in no accumulation
especially on roads. Gusty northwest winds will continue this
afternoon with some gusts up to 35-40 mph mainly along the
Upslope snow showers will begin this afternoon and intensify this
evening as saturation is best in the SGZ along the Allegheny Front.
Accumulating snow is expected with 2 to 4 inches expected across
western Grant and western Pendleton counties. 1-3 inches expected
elsewhere along the Allegheny front. Subsidence starts to play a
role into Thursday morning and snow showers will begin to improve
and end in the morning. A winter weather advisory is in effect for W
Grant/W Pendleton tonight through Thu morning.
Further east...snow showers can not be ruled out tonight. The snow
squall parameter shows the potential for streamers to move east of
the mtns and across northern MD. Coverage seems limited however will
need to be watched closely with temperatures dropping into the
20s. A dusting is possible in streamers.
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
Snow showers will taper off by Thu afternoon however strato-cu
deck is expected through the afternoon. Cool conditions expected
Thursday with temps staying mostly in the 30s/L40s. High pressure
briefly moves overhead Thu night resulting in a cool night with
temperatures in the 20s. Another shortwave trough will drop west of
the region into Friday and clouds will likely increase across the
region Friday. Temps will rise back to normal Friday afternoon.
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
A low pressure system over the Southeast U.S. will gradually spread
some moisture northward into the mid-Atlantic region Saturday. There
is a slight chance of rain showers Saturday night in association
with the advecting moisture.
High pressure will build into the region Sunday through Tuesday. Dry
conditions and mild temperatures will evolve during this stretch of
By late Tuesday and Tuesday night, a cold front should sag across
the region and then stall overhead Wednesday. There is a chance for
rain showers later in the afternoon Tuesday, Tuesday night and
Wednesday in association with the front. Temperatures will be
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
Gusty winds will continue at the terminals today. NW winds 15-25
sustained with gusts up to 35 knots expected this afternoon. Gusty
winds will likely persist this evening with the higher gusts
Prevailing VFR conditions expected across the terminals through
Thursday however iso-sct RA/SN showers are possible mainly tonight.
Brief periods of reduced vsbys are possible however confidence is
very low to pinpoint showers. Best chance would be MRB/IAD.
Vfr conditions Saturday through Sunday night. Winds southwest 5
knots Saturday becoming west-northwest 5 knots Saturday night. Winds
northwest 5 to 10 knots Sunday through Sunday night.
A cold front will cross the waters this afternoon. Gusty NW winds
expected with gusts in the mid 30s. A Gale Warning is in effect
today through Thu morning. Isolated to scattered showers are
expected across the waters this afternoon and may cause a sudden
increase in winds as well. Gusty winds will continue on the
waters through this time however a lull is possible overnight
especially across the Tidal Potomac. Strong mixing will pick up
again Thu morning.
SCA headline in effect through Thursday evening. SCA may need
to be extended further into Thursday night for portions of the
Chesapeake Bay. Winds abate early Friday as high pressure builds
Winds anticipated to be mostly 10 kt or less this weekend.
Light winds ahead of a cold front have resulted in higher than
normal tidal anomalies. The high tide at Straits Point in St.
Mary`s county will be very close to minor flood stage at their
high tide late this afternoon. As NW winds increase anomalies
will decrease prior to the high tide. It will be close and need
to be monitored.
WV...Winter Weather Advisory from 7 PM this evening to 10 AM EST
Thursday for WVZ501-505.
MARINE...Small Craft Advisory from noon to 6 PM EST Thursday for
Gale Warning until noon EST Thursday for ANZ530>543.