831
FXUS61 KLWX 120140
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
940 PM EDT Mon May 11 2026

.WHAT HAS CHANGED...
Added Page County and Frederick County in Virginia to the Frost
Advisory tonight. Otherwise, the Freeze Warnings and Frost
Advisories from earlier in the day are still valid.

&&

.KEY MESSAGES...
1) A late season frost/freeze west of the Blue Ridge tonight.

2) Gusty thunderstorms are possible Wednesday afternoon and
evening.

3) After another cool down, above average temperatures return
for the weekend into early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...A late season frost/freeze west of the Blue
Ridge tonight.

Temperatures are quickly falling through the 50s into the 40s
during the mid-evening hours and will continue to drop through
the night.

A surface anticyclone initially over the Great Lakes is forecast
to push toward the Mid-Atlantic region tonight. Dew points are
likely to fall given the continued cool/dry advection. The
pattern is supportive of a rather chilly night ahead, especially
for those west of the Blue Ridge Mountains. In these regimes of
clear skies and calm winds under high pressure, model guidance
can be notoriously too warm. Consequently, have lowered
temperatures and dew points accordingly which would be
supportive of a rather widespread frost/freeze. Tonight`s lows
are likely to fall into the upper 20s to low 30s along the
Alleghenies where Freeze Warnings are in place from 1 AM-8 AM.
Off to the east, much of the Shenandoah Valley is in a Frost
Advisory as lows drop into the mid 30s. We have recently added 2
more counties in Virginia to the Frost Advisory...Page and
Frederick. For those with outdoor vegetation or sensitive
plants, ensure to take ample precautions to protect them from
this late season chill. All frost/freeze products expire by 8 AM
Tuesday before temperatures warm quickly underneath sunny
skies. This will set the stages for a return to the upper 60s to
mid 70s which is accompanied by dry conditions.


KEY MESSAGE 2...Gusty thunderstorms are possible Wednesday
afternoon and evening.

A broad shortwave currently tracking across southern portions of
Alberta and Saskatchewan will be the next weather maker across
the region. Height falls accompanying this system push through
on Wednesday evening which drives the next cold front across the
Mid-Atlantic states. Although forcing and vertical shear are
fairly impressive for mid-May, the degree of buoyancy is much
more questionable. The latest model guidance indicates deep-
layer shear on the order of 40-50 knots, but with instability
running closer to 250 J/kg. This latter artifact of the forecast
is largely driven by the limited moisture advecting into the
region. On Wednesday morning, surface dew points are forecast to
only be in the 40s, but could spike into the low/mid 50s with
continued southerly warm/moist advection. As it stands, the
Storm Prediction Center has maintained a Day 3 Marginal Risk
(Level 1 of 5) across areas west of the Blue Ridge. Damaging
wind gusts would be the main threat given steepening low-level
lapse rates with daytime heating. Any severe component to these
storms should diminish by later in the evening. Some showers and
a few rumbles of thunderstorm may persist into the first half of
the overnight hours.


KEY MESSAGE 3...After another cool down, above average
temperatures return for the weekend into early next week.

A fairly typical springtime pattern continues through late in
the work week as temperatures rise and fall with frontal
passages. The earlier mid-week trough is expected to close off
in the vicinity of the upper Mid-Atlantic to southern New
England on Thursday. Not only will this keep temperatures cooler
with some enhanced cloud cover, scattered mountain showers look
possible during the daytime hours. This barreling closed low
slowly pulls away from the New England coast by early Friday
which results in diminishing shower chances. Continued
northwesterly flow will keep temperatures to near to below
average though.

A trailing longwave ridge moves in for Saturday while flattening
in time as a trough pushes across southern Ontario. However, net
height/thickness increases will support the start of a marked
warming trend by Saturday. Low-level winds shift to west to
southwesterly over the weekend which aids in the shift to warmer
weather. Widespread low/mid 80s are expected for Saturday before
nearing the 90 degree mark on Sunday. For the mountains, 70s
would be more commonplace. Box-and-whisker plots show the
potential of further warming into early next week, but with some
building spread. Any low-end shower and thunderstorm chances
appear more terrain driven and likely will be disorganized
underneath the upper ridge.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
Expect VFR conditions at all terminals through the remainder of
the evening. Some patchy fog could materialize near KCHO, but
have kept the forecast conservative with a 4 SM visibility in
the TAF. Expect winds to turn light overnight underneath high
pressure.

VFR conditions are expected for Tuesday with a return to light
southerlies for the second half of the day. Wednesday has the
potential to be a bit more active with the approach of the next
system. Some restrictions are possible during the
afternoon/evening hours. This comes with a background south-
southwesterly wind which could gust to around 20 to 25 knots.
The cold front tracks through late Wednesday which brings an end
to any showers.

Expect VFR conditions for Thursday and Friday with a prevailing
northwesterly wind. Afternoon gusts each day could push into the
20 to 25 knot range depending on how tight gradients end up
being. Dry weather continues into Saturday with a shift to
southwesterlies.

&&

.MARINE...
Expect winds to remain on the lighter side (5 to 10 knot gusts)
through early Tuesday. The next chance for any Small Craft
Advisories would be late Tuesday into all of Wednesday due to
southerly channeling effects. Gusts of 20 to 25 knots will be
commonplace across a majority of the waters. Some late
afternoon to evening convection could impact the waters as the
cold front approaches from the west. Any stronger storm may
require Special Marine Warnings.

Winds shift to west-northwesterly early Thursday behind the cold
front. Expected winds should stay below advisory levels as this
occurs. Northwesterlies persist into Thursday and Friday which
may require Small Craft Advisories at times.

&&

.TIDES/COASTAL FLOODING...
Expect a gradual uptick in water levels ahead of the mid-week
system. The influence of increasing southerlies will carry the
tidal forecast to Action at Annapolis during times of high tide.
The Stevens ensemble shows the potential for Minor tidal
flooding by early Thursday. Expect anomalies to fall thereafter
as winds shift to northwesterly.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Freeze Warning from 1 AM to 8 AM EDT Tuesday for MDZ501-509-
     510.
     Frost Advisory from 1 AM to 8 AM EDT Tuesday for MDZ502.
VA...Freeze Warning from 1 AM to 8 AM EDT Tuesday for VAZ503-504.
     Frost Advisory from 1 AM to 8 AM EDT Tuesday for VAZ025>029.
WV...Freeze Warning from 1 AM to 8 AM EDT Tuesday for WVZ501-503-
     505-506.
     Frost Advisory from 1 AM to 8 AM EDT Tuesday for WVZ050-051-
     055-502-504.
MARINE...None.

&&

$$

DISCUSSION...BRO/KLW
AVIATION...BRO/KLW
MARINE...BRO/KLW

NWS LWX Office Area Forecast Discussion