129
FXUS61 KLWX 180748
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
348 AM EDT Wed Mar 18 2026

.WHAT HAS CHANGED...
With northwesterly winds remaining a bit gusty over the marine
waters, have extended Small Craft Advisories until 6 AM across
portions of the waters. From Friday evening and night, rainfall
chances have increased relative to previous forecast packages.

&&

.KEY MESSAGES...
-1) Today will bring another day of below average temperatures,
 but with less wind, before a warming trend ensues.

-2) Temperatures warm through the weekend with a cold front
 bringing cooler temperatures early next week.

&&

.DISCUSSION...

KEY MESSAGE 1...Today will bring another day of below average
temperatures, but with less wind, before a warming trend ensues.

The early morning surface analysis places a broad area of high
pressure which extends from the Ohio and Tennessee Valleys down
to the northern Gulf of America. Being just east of the
anticyclone, a residual light west-northwesterly wind remains
over the local area. Despite such winds, the cold and dry nature
of the air mass has allowed 07Z/3 AM temperatures to plunge into
the 20s, with spotty upper teens. The true cool spot is along
the Allegheny Front with widespread teens noted, much of which
is aided by recent snowpack.

Based on nighttime satellite imagery trends, an uptick in
mid/high clouds is expected ahead of a shortwave moving across
the Ohio Valley. These should largely stick around through the
morning hours before some improvements occur for the second half
of the day. With high pressure shifting position across the
eastern U.S., winds eventually shift to southerly by early this
afternoon. Relatively weak gradients will keep winds weaker than
recent days, with any gusts staying around 10 mph or less,
locally up to 20 mph in the higher terrain. Today`s forecast
highs will again be in the upper 30s to low 40s, but a notable
warm up occurs from the Blue Ridge westward. Temperatures
rebound by around 10 to 15 degrees which carries Allegheny
Mountain highs into the upper 20s to mid 30s. Heading into
tonight, while chilly, temperatures return closer to freezing
given light southerly flow.

For Thursday and Friday, high pressure persists near the Eastern
Seaboard. Looking aloft, northwesterly flow prevails given well
above average heights centered over the southwestern U.S.
However, the 1000-500 mb layer gradually warms through the
period with 24-hour rises of around 6 to 8 dm per day.
Increasing thicknesses coupled with mainly south to
southwesterly flow will return temperatures to the 50s by
Thursday before pushing into the low 60s on Friday. Some shower
chances move into the picture by Friday evening/night as a
clipper system races across the area. With Friday night`s low
temperatures in the 40s, it will be an all rain event.


KEY MESSAGE 2...Temperatures warm through the weekend with a
cold front bringing cooler temperatures early next week.

Surface high pressure centered over the southeast remains overhead
Saturday and Sunday with temperatures expected to gradually warm
each day. Highs on Saturday will range from the mid 50s along the
MD/PA border to the low 70s in central VA. On Sunday, high
temperatures will warm further with those in northern MD in the
60s and those in central VA in the mid 70s.

Precipitation chances increase Sunday as a cold front drops through
the forecast area. In the wake of the front, Canadian surface high
pressure builds overhead with dry conditions and cooler temperatures
expected on Monday. Highs will be in the 40s to mid 60s across the
area. High pressure continues to build overhead on Tuesday with
highs in the 40s to low 50s. A surface trough along the Alleghenies
will bring increased precipitation chances on Tuesday. Precipitation
chances remain low (less than 30 percent) at this time, although
cold temperatures could lead to some snow west of the Blue
Ridge.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
High pressure will dominate the pattern through Friday which
will favor prevailing VFR conditions. Winds will initially be
out of the northwest before shifting to southerly for the second
half of today. As high pressure relocates the next couple of
days, winds turn south to southwesterly on Thursday and Friday.
Gradients remain weak which limits the wind gust potential.

Southwest winds on Saturday blow 5 to 10 knots with gusts to 15
knots expected. On Sunday, west winds in the morning shift to
northwest in the wake of a cold front Sunday afternoon. Winds
increase to around 10 knots, gusting to 20 knots.  Precipitation
chances increase across the terminals Sunday afternoon, although
remain low. VFR conditions are expected both days with brief
restrictions possible during precipitation on Sunday.

&&

.MARINE...
A brisk northwesterly wind continues from the Bay Bridge
southward in the Chesapeake Bay as well as for the lower tidal
Potomac. Gusts up to 20 knots are possible through 6 AM with
Small Craft Advisories being extended to cover this threat. This
could linger slightly longer over southern sections of the bay.
Winds shift to southerly for the second half of today. Weak
gradients through Friday should limit the gust potential over
the waters. Some southerly channeling effects are possible by
late Friday which could near advisory caliber.

Southwest winds remain below SCA criteria on Saturday. Winds
increase overnight with SCAs possible across the open waters. West
winds on Sunday morning shift to northwest in the wake of a cold
front Sunday afternoon. Small Craft Advisories are likely throughout
the day as winds gust 20 knots.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EDT early this morning for
     ANZ532>534-537-540>543.

&&

$$

DISCUSSION...AVS/BRO
AVIATION...AVS/BRO
MARINE...AVS/BRO

NWS LWX Office Area Forecast Discussion