233
FXUS61 KLWX 281903
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
303 PM EDT Tue Apr 28 2026

.WHAT HAS CHANGED...
The only change made to the forecast for this update cycle was
to slightly slow down the progression of showers along the warm
front Wednesday morning.

&&

.KEY MESSAGES...
1) Increasing shower and thunderstorm chances through mid-week
as a frontal system approaches.

2) Multiple nights of frost/freezing conditions possible late
week into the weekend.

3) Additional rain chances Friday into Saturday as a trailing
disturbance passes through.

&&

.DISCUSSION...
KEY MESSAGE 1...Increasing shower and thunderstorm chances
through mid-week as a frontal system approaches.

Mostly cloudy skies expected to continue this afternoon and
throughout the overnight hours. Afternoon highs still rising
into the low 60s for most, about on par with the forecast.
Overnight lows in the upper 40s to low 50s.

Wednesday continues to present itself as the most active day of
the forecast period. As is common in convective forecasting in
the area, morning clouds/showers may hinder the severe threat
later in the afternoon/evening. Starting off the day, warm
advection showers will overspread the area from southwest to
northeast by mid-morning. Guidance is split on just how much
rain comes from this, but at the very least, we will be dealing
with junky morning clouds and some drizzle most likely.A The
actual surface warm front should reside over southwestern
Virginia around daybreak. Through the day, expect this warm
front to slowly lift northeastward in time before reaching the
metro areas by Wednesday evening. Given the later arrival of
this milder/more unstable air mass, this might not time as well
with the peak diurnal heating cycle. If anything, the better
shot would come during the evening as a cold front pushes
eastward across the region. Despite questionable instability,
the 0-6 km shear runs around 45 to 55 knots which is plenty
sufficient for severe thunderstorm development. Thus, there is a
risk of some damaging winds as this cold front tracks through
on Wednesday evening. A Marginal Risk continues to be advertised
by the Storm Prediction Center for the entire area to cover
this risk.

Showers and a few thunderstorms linger into the overnight hours.
However, the area should experience a drying trend from west to
east behind this exiting baroclinic zone.

A cool and breezy day is expected on Thursday with northwesterly
gusts to around 20 to 30 mph. Despite the large drop in 850-mb
temperatures (8 to 10C fall between Wednesday and Thursday
afternoons), a well mixed boundary layer should overcome this
cooling effect. Forecast highs on Thursday should still push
into the upper 50s to mid 60s (40s to mid 50s across the
mountains). Outside of some upslope aided rain showers
along/west of the Alleghenies, expect a dry day. Nighttime
conditions yield lows falling into the mid 30s to mid 40s.


KEY MESSAGE 2...Multiple nights of frost/freezing conditions possible
late week into the weekend.

High pressure will build in across the region behind a departing
closed low pressure system. Cool air advection, drier air, and
diminishing winds could all lead to possible frost formation in
parts of the region Friday night through Sunday night. Freezing
temperatures could also evolve and spread eastward toward the more
populated areas outside of the Alleghenies. Low temperatures each
night could be widespread 30s with lower 40s well to the east. We
will see a slight uptick in the winds during the day due to diurnal
differences, but then become light to calm widespread after sunset
each day.


KEY MESSAGE 3...Additional rain chances Friday into Saturday as
a trailing disturbance passes through.

As the main trough of low pressure pulls away from the region, a
trailing disturbance or two could follow suit and bring us a few
rain showers to the region both Friday and Saturday. It is not out
of the question that higher elevations in the Alleghenies could
encounter a little light rain and snow mix but accumulations would
be light. There is even a hint that a disturbance could move across
the region early next week and bring us a little more rain relief.
Temperatures would be more seasonable early next week.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
The remainder of the afternoon into the evening should remain
dry in the wake of this morning`s showers. Winds will begin
shifting out of the southeast into tonight.

Widespread rain showers and some late afternoon to evening
thunderstorms are in the forecast for Wednesday. Restrictions
look likely for large portions of the day. Any severe
thunderstorms would be capable of damaging wind gusts, with the
best chance of this coming along the cold front itself in the
early evening hours. Expect mainly southeasterly winds through
the day with afternoon gusts up to around 15 to 20 knots. Winds
shift to west to northwesterly on Wednesday night behind a
strong cold front.

VFR conditions are likely on Thursday with continued
northwesterly gusts to 20 to 25 knots.

Sub-VFR conditions could occur at a few of the terminals depending
on rain shower coverage Friday and again on Saturday. Otherwise,
terminals that do not encounter these brief bursts of rain showers
could stay VFR. Winds northwest 10 to 15 knots gusts up to 20 knots
Friday and then again on Saturday. Winds will diminish each
night.

&&

.MARINE...
Winds should remain below SCA criteria for the most part this
evening, but will be on the increase by Wednesday morning.

Small Craft Advisories have been issued for Wednesday as winds
will be on the increase, with further wind increases into
Wednesday night and Thursday as winds shift to northwesterly
behind a cold front. Gusts up to 20 to 25 knots are possible in
this post-frontal environment. Before this cold front crosses
the waters late Wednesday, some severe weather potential exists
which may warrant a few Special Marine Warnings.

Small Craft Advisories are likely needed through Thursday
afternoon and into the early evening. While most marine zones
see winds drop off into the night, winds could remain elevated
over the southern most waters.

Small Craft Advisories possible Friday and again on Saturday,
primarily in the northern Chesapeake Bay. Winds northwest 10 to
15 knots gusts 20 knots each day.

&&

.TIDES/COASTAL FLOODING...
Onshore flow continues as high pressure exits the Atlantic coast
and waves of low pressure approach from the west. Many
locations will reach Action Stage during high tide through
Wednesday, with Minor tidal flooding possible, especially at
Annapolis and Dahlgren. A couple other tidal sites like
Alexandria and Havre de Grace could get close during the higher
of the two astronomical high tides, as well. Water levels begin
to drop off by Thursday as winds shift to northwesterly.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 11 AM Wednesday to 6 AM EDT
Thursday for ANZ530>543.

&&

$$

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

NWS LWX Office Area Forecast Discussion