328
FXUS61 KLWX 071805
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
205 PM EDT Thu May 7 2026

.WHAT HAS CHANGED...
Chances for showers have been added to the forecast for
this afternoon along and southeast of a line that extends
roughly from Annapolis to DC to Culpeper to Waynesboro.

&&

.KEY MESSAGES...
- 1) Cooler temperatures today and tomorrow, with frost likely
  tonight in the Alleghenies.

- 2) Milder for the weekend with increasing rain chances. Below
  normal temperatures return early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Cooler temperatures today and tomorrow, with
frost likely tonight in the Alleghenies.

Broad upper troughing resides over eastern North America this
afternoon. Ascent ahead of a shortwave disturbance rounding the
base of the trough to our west is forcing the development of
scattered showers well to the north of a frontal boundary that
is now located over the Carolinas. These showers are located
along and southeast of a line extending roughly from Annapolis
to DC to Culpeper to Waynesboro as of 2 PM. This area of showers
will continue to slowly sink off toward the south and east over
the remainder of the afternoon. Just to the northwest of those
showers, skies have largely cleared out, leading to mostly sunny
skies. Temperatures have climbed into the 60s where sunshine
has broken out, but temperatures remain stalled out in the 50s
where the thicker cloud cover and showers reside.

The upper trough axis will swing through tonight, and large
scale subsidence will start to increase as it passes to our
east. Any showers will come to an end, and skies should
gradually clear out from west to east. A ridge of high pressure
is expected to build to our south and west, extending
northeastward toward the Allegheny Front. As a result, sheltered
mountain valleys in the Alleghenies will likely go calm later
tonight. The combination of light winds and clear skies will
create ideal radiational cooling conditions there, which should
allow temperatures to drop back into the 30s. Frost Advisories
have been issued tonight for Highland, Pendleton, western Grant,
and Garrett Counties. Further east, light northwesterly wind
will likely continue through the night ahead of the building
high. This should keep temperatures a few degrees warmer, with
lows in the low to mid 40s for most.

After a sunny start, some fair weather cumulus clouds should
develop in response to daytime heating tomorrow. Temperatures
will rebound nicely after a cool start, ultimately reaching
highs in the upper 60s to lower 70s. Another shortwave
disturbance will pass through on Saturday, potentially leading
to development of a few showers or thunderstorms. Much of the
day will remain dry however, with temperatures climbing into the
low to mid 70s.


KEY MESSAGE 2...Milder for the weekend with increasing rain chances.
Below normal temperatures return early next week.

As surface high pressure moves offshore, and upper ridging builds
ahead of an approaching trough, this weekend looks to be quite warm
across the region. Highs Saturday rise into the mid 70s, while Sunday
could rise into the upper 70s to low 80s (subtract 7-10 degrees for
mountain locations. Both days will see chances for thunderstorms due
to an approaching cold front. Saturday will see storms along the pre-
frontal trough/leading shortwave, while Sunday will see the better
chance with along the actual cold front late in the day/evening into
Sunday night. While neither day currently exhibits a substantial
severe thunderstorm risk, some gusty winds and small hail can`t be
ruled out. A secondary wave of low pressure is likely to develop as
the front crosses the Mid-Atlantic, though it remains to be seen if
this enhances rainfall locally or causes it to "skip" over the
region as many systems have done recently.

In the wake of a somewhat active and warm weekend, cooler than
normal weather is set to return for the first half of next week
behind the front. Rain chances may linger into Monday morning before
departing as the aforementioned cold front swings offshore.

With high pressure building in from the west Monday night into
Tuesday, overnight low temperatures could feasibly drop into the mid
30s resulting in some frost potential for the Alleghenies heading
into early Tuesday morning.

As the high drifts offshore, the threat of a few pop up showers or
thunderstorms may re-emerge by the middle of next week.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Prevailing VFR conditions are expected at the terminals through
Saturday. A few passing showers may be possible at DCA or CHO
this afternoon, but otherwise dry conditions are expected
through the day tomorrow. The wind direction forecast is a
challenging one over the next 24 hours at all TAF sites, with
several large wind shifts likely. The DC/Baltimore terminals
should eventually go southerly later this afternoon,
southwesterly this evening, northwesterly overnight, and then
westerly during the day tomorrow. Winds may gust to around 20-25
knots tomorrow afternoon within westerly flow. Winds turn
southerly tomorrow night and persist through Saturday. A few
passing showers or storms may also be possible on Saturday as a
disturbance passes to our north.

VFR conditions can be expected for much of Sunday. However, a
frontal boundary crosses the region during the late
afternoon/evening hours and into the overnight. Widespread rain
and a few thunderstorms can be expected as this front traverses
the region. Expect VSBY reductions and reduced CIGs during this
time.

Rain may linger into Monday morning, but should be out by mid-late
morning. This will give way to partly cloudy skies and NNW winds
around 15 to 20 knots by Monday afternoon.

Less wind and less clouds can be expected Tuesday, with VFR
conditions expected throughout.

&&

.MARINE...
Winds will be light and variable through the remainder of this
afternoon into the evening. Later tonight winds shift to out of
the northwest. Winds may briefly gust to low-end SCA levels in
northwesterly flow. Due to the short time duration, those gusts
will likely be highlighted in an MWS. Winds tomorrow will
generally be out of the west to southwest. Gusts may potentially
reach low-end SCA levels across the narrower waters of the Upper
Bay and Upper Tidal Potomac. Winds become southerly tomorrow
night through the day Saturday. Gusts may reach SCA levels
within channeled southerly flow tomorrow night into Saturday.

Showers and thunderstorms along a cold front will likely impact the
waters later in the day on Sunday afternoon. It remains to be seen
if these will be strong enough to require Special Marine Warnings.
The cold front will cross the waters early Monday with a shift to
northwesterlies with gusts up to 20 to 25 knots. Small Craft
Advisories will likely be needed into much of Monday.

Winds will be a little less on Tuesday, so SCAs may not be
needed.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Frost Advisory from 11 PM this evening to 8 AM EDT Friday for
     MDZ509-510.
VA...Frost Advisory from 11 PM this evening to 8 AM EDT Friday for
     VAZ503-504.
WV...Frost Advisory from 11 PM this evening to 8 AM EDT Friday for
     WVZ501-505-506.
MARINE...None.

&&

$$

DISCUSSION...CJL/KJP
AVIATION...CJL/KJP
MARINE...CJL/KJP

NWS LWX Office Area Forecast Discussion