213
FXUS61 KLWX 111935
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
335 PM EDT Tue Aug 11 2026

.WHAT HAS CHANGED...
Monitoring the evolution of upstream thunderstorm clusters and
how the environment evolves through this evening. Wednesday

&&

.KEY MESSAGES...
- 1) The risk of severe thunderstorms seems to be decreasing
  through tonight, although upstream thunderstorm complexes
  still need to be monitored.

- 2) Showers and thunderstorms remain possible at times
  Wednesday through Friday.

- 3) Drier conditions anticipated heading into next week, with
  a few showers & thunderstorms possible late this weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...The risk of severe thunderstorms seems to be
decreasing through tonight, although upstream thunderstorm
complexes still need to be monitored.

The thunderstorm complex that was in Ohio earlier dove southward
toward higher instability in far southwest VA, with only some
stratified rain affecting western/southwestern portions of the
CWA over the next couple hours. Additional thunderstorms across
western Ohio, Indiana, and Illinois are now also showing signs
of diving southward due to the cold pool left by the eastern
Ohio storms. While some 12Z CAMs showed remnants of this
convection reaching the area this evening, this is increasingly
in question. East of the dense overcast, there has been some
filtered heating is occurring. This will result in some
instability, but it isn`t clear there will be enough of a
trigger to kick off any storms locally. Most recent CAMS have
backed off on local development, but can`t totally rule out a
few isolated to scattered storms mainly east of the Blue Ridge.
Shear is a bit more marginal today, but it`s still possible
there could be a stronger storm with gusty to damaging winds.
This threat would obviously be highest if an organized complex
moved in from the west.

Given the current trajectories of the storms to the west, it`s
possible additional heavy rain avoids Garrett County. If these
trends continue, the Flood Watch may be cancelled early.

Based on current models, the second half of the night should
largely be dry. There may be some patchy fog if clearing occurs.
Lows will be in the 60s to lower 70s.


KEY MESSAGE 2...Showers and thunderstorms remain possible at
times Wednesday through Friday.

The west to east oriented cold front will remain near the area
through Friday. The main question is whether we remain in west
or northwest flow and more stable conditions, or if the richer
moisture is able to advect back in from the southwest. Periods
of cloud cover could also be an issue that affects diurnal
destabilization. Many, but not all, models show a relative lull
on Wednesday as the greatest instability remains south and west
of the area.

One, possibly two, waves of low pressure may track along the
front between Wednesday night and Friday. This could lift the
front northward, or at least provide a more notable source of
forcing other than subtle shortwaves aloft. It`s unclear how
well shear, instability, and forcing will overlap, but it is
possible some stronger storms could develop if they do. ML/AI
guidance has mixed signals on severe probabilities, but overall
lower compared to Monday and today.

Temperatures will likely be within several degrees of normal
through Friday with elevated humidity levels.


KEY MESSAGE 3...Drier conditions anticipated heading into next
week, with a few showers & thunderstorms possible late this
weekend.

Dry air moves in from the Great Lakes region at the start of the
weekend as upper-level ridging builds over the lower Mississippi
Valley by Saturday. Temperatures remain slightly cooler than average
during this period with fewer precipitation chances overall. As
this high pressure builds towards the south, shortwave energy
forming north of the ridge over the Great Lakes will track towards
the Mid-Atlantic Sunday and heading into Monday. This could produce
chances for additional showers and thunderstorms, with most medium-
range severe outlooks currently producing rather marginal 5-15
percent probabilities for severe thunderstorms.

Once this shortwave system passes through, zonal flow transitions
over the region, reducing thunderstorm chances overall. Temperatures
will start to increase during this period as surface high pressure
transitions into the region.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR conditions will likely prevail through Friday outside of
thunderstorms and small potential for morning fog.

Stable conditions may limit thunderstorm development or
maintenance across much of the area through tonight, although
some guidance still pops a few showers and thunderstorms this
afternoon. Given decreasing prospects and isolated coverage if
they do form, removed PROB30 groups this afternoon in the metro
TAFs. An area of stratified rain from earlier thunderstorms is
crossing the Appalachians, but that seems to be evaporating with
little to no lightning now, so this mention may be removed at
MRB/CHO.

Some earlier model runs showed upstream convection in the Ohio
Valley moving into the area this evening. Left PROB30 groups in
the TAFs for this potential, but current observations suggest
these storms may be turning southward toward higher instability.
So in the end, it`s possible the TAF airports remain dry through
tonight with mainly mid and high clouds.

Many (but not all) models are now showing a relatively lull in
storm chances Wednesday, so am not mentioning any chances at
this time.

Showers and thunderstorms remain possible Thursday and Friday
but will depend on the position of a cold front and the timing
of any disturbances. Outside of the thunderstorms expect patchy
fog between the terminals each morning. Winds will remain light
(outside of any thunderstorm outflows) between northwest and
south west.

Prevailing VFR conditions are anticipated at the start of the
weekend. On Sunday, a frontal boundary moves through the region that
could generate showers & thunderstorms as well as periodic sub-VFR
conditions at terminals. Northerly winds shift southerly as this
front passes through.

&&

.MARINE...
Overall sub-SCA level winds are expected through Friday. Wind
direction is a bit uncertain as a cold front slowly approaches
and various disturbances/pass through, although they should
average between northwest and southwest. There could be an
enhanced northwesterly surge once the front does push through
late Friday, with advisory conditions possible.

Outside of the background winds, expect daily shower and
thunderstorm chances each afternoon and evening through Friday
(though can`t rule out storms overnight and in the mornings as
well). At this time, chances are decreasing for today/tonight,
and may be rather limited Wednesday as well. However, any storms
that do form through the end of the week will potentially have
gusty winds and frequent lightning.

SCAs are possible on Saturday morning with northerly winds before
diminishing over the afternoon. A frontal boundary passes through
the region over the weekend, with winds increasing to SCA conditions
again on Sunday as winds shift southerly.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Flood Watch through late tonight for MDZ509-510.
VA...None.
WV...None.
MARINE...None.

&&

$$

DISCUSSION...ADS/EST/SRT
AVIATION...ADS/EST/SRT
MARINE...ADS/EST/SRT