Area Forecast Discussion
Issued by NWS Sterling, VA
FXUS61 KLWX 160210 AAA
Area Forecast Discussion...UPDATED
National Weather Service Baltimore MD/Washington DC
910 PM EST Wed Feb 15 2017
High pressure builds overhead through Friday and then remains
nearby into early next week.
.NEAR TERM /THROUGH THURSDAY/...
Snow showers have begun to increase in coverage and intensity
across the Potomac highlands and western MD. Mid-level lapse
rates will continue to steepen rest of this evening as upper
trough and associated cold pool aloft move across the area with
best snowfall rates expected through 06Z. After 06Z, low-level
water vapor (7.3 micron) synthetic imagery from NSSL WRF-ARW
and model soundings indicate increasing drying and lowering
inversions. Fcst Froude numbers from 18Z NAM suggest streamers
may make it east of the Blue Ridge with flurries possible.
Brisk on Thu with gusts up to about 30 kts.
.SHORT TERM /THURSDAY NIGHT THROUGH FRIDAY NIGHT/...
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 /02Z THURSDAY THROUGH MONDAY/...
Gusty winds will likely persist this evening with the higher
gusts across BWI/MTN.
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 Gale Warning is in effect through Thu morning. 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.
WV...Winter Weather Advisory until 10 AM EST Thursday for WVZ501-
MARINE...Small Craft Advisory from noon to 6 PM EST Thursday for
Gale Warning until noon EST Thursday for ANZ530>543.