Area Forecast Discussion
Issued by NWS Sterling, VA
FXUS61 KLWX 161332
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
932 AM EDT Thu Mar 16 2017
High pressure will gradually build east from the
mid-Mississippi valley through early Friday. A cold front will
move through the area Saturday. High pressure builds over the
area for the second half of the weekend into early next week.
.NEAR TERM /THROUGH TONIGHT/...
High pressure will continue to approach from the west. A
blustery northwest wind will continue with frequent gusts around
25 to 35 mph through this afternoon. Drier air will allow for
more sunshine...which will cause max temps to be a bit milder
compared to Wednesday but still below climo. Max temps will
range from the 20s in the mountains to the upper 30s and lower
40s near Washington and Baltimore...to the middle 40s in central
A sct/bkn cu deck due to increased mixing will develop across
northern and central areas through this afternoon. A few
flurries cannot be ruled out...but no accumulation is expected
with surface temps rising above freezing.
High pressure moves to the south tonight. Clear and cold
conditions are expected tonight with temps dropping into the
20s and teens in the mtns.
.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
High pressure over the SE US will move to the east Friday and
southerly flow will begin. A warm front will approach the region
from the west Friday morning and mid-high level clouds will
increase. Temps will climb into the 40s by Friday afternoon with
some places across the Piedmont seeing 50. Warm air advection
aloft will move into the region Friday and rain is expected to
move from west to east through the afternoon. As a warm front
approaches Friday night temperatures are going to slowly drop or
stay steady into Saturday morning. At this time temps look to
stay above freezing however the potential exists for temps to
drop near freezing mainly across the Allegheny Front and far
northern MD. Due to the warm air aloft...fzra can not be ruled
out across these areas. Although fzra in March is difficult in
the Mid-Atlantic, the recent cold snap may keep the ground cold
enough for some impact. At this time confidence is low that
temperatures will drop to sub- freezing.
A cold front will move across the region Saturday. Guidance
indicates low pressure developing along the front. Rain is possible
across the region however there will likely be a lull across the
outlook area with better forcing to the south and east. Northwest
flow will increase behind the departing low Saturday and upslope
snow showers will begin and continue through Saturday night.
Accumulation of 1-2 inches is possible along the Allegheny Front
during this time.
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Cool and breezy conditions expected Sunday as low pressure
moves farther away from the coast. Chilly Sun night as sfc ridge
builds and winds diminish. A weak cdfnt moving through the
eastern Great Lks Mon will bring a chance of rain showers Mon
and Mon night. Some notable differences are seen with timing of
that frontal passage between latest GFS and ECMWF models which
could result in showers persisting through Tuesday. By the
middle of next week, high pressure will be building into the
region from the upper midwest with seasonably cool and dry
.AVIATION /14Z THURSDAY THROUGH MONDAY/...
VFR conditions expected through Friday. Northwest winds will
gust around 25 knots through this afternoon. Winds will diminish
tonight. A sct/bkn cu deck is expected this afternoon with cigs
around 5kft. Mid-high level clouds move into the region tonight
and rain is likely Friday into Friday night. Reduced cigs are
possible into Saturday morning. A cold front will cross the
region Saturday. NW increase again.
Gusty NW winds expected Sun diminishing Sun night.
Northwest winds will continue today. A Small Craft Advisory is in
effect today for all waters. Winds will gradually subside further
tonight into Friday. A Small Craft Advisory is in effect for
portions of the waters tonight. A warm front will pass through the
waters Friday night. Rain is likely Fri-Saturday. A cold front will
cross the waters Saturday. NW winds increase again Sat-Sat night.
SCA are likely during this time.
SCA conditions likely Sun-Sun night.
Record low maximum temperatures were set at IAD and
BWI yesterday. See RERs for those two airports.
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ530>534-537-
Small Craft Advisory until 8 PM EDT this evening for ANZ535-