552
FXUS61 KLWX 131913
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
313 PM EDT Tue Oct 13 2026

.WHAT HAS CHANGED...
Forecast package remains on track. Some subtle updates to shower and
thunderstorm chances late Wednesday afternoon and evening as a cold
front passes through.

&&

.KEY MESSAGES...
- 1) Near record warmth and mainly dry conditions continue
  through Wednesday.

- 2) A strong cold front moves through on Friday, bringing
strong winds, the potential for thunderstorms, and then cold
conditions in its wake for this weekend.

&&

.DISCUSSION...
KEY MESSAGE 1...Near record warmth and mainly dry conditions continue
through Wednesday.

Weak high pressure nearby and mid-level ridging will continue to
dominate the forecast heading into Wednesday. The high itself will
slide offshore later today allowing the mid-level ridge to buckle
heading into Wednesday. Meanwhile, a series of shortwave
disturbances will quickly slide from west to east across northern
portions of the forecast region as a cold front drops south from the
Great Lakes and Ohio River Valley. This front will touch off showers
and a few thunderstorms late Wednesday afternoon and evening, mainly
in areas along and north of I-66/US-50 and US-48. A Marginal Risk
(Level 1 out of 5) for severe weather remains in place for portions
of western MD, eastern WV, and the VA Highlands Wednesday afternoon
where better instability/shear will reside. Thunderstorm coverage
overall will be isolated to scattered with damaging winds as the
primary concern (especially west of the Blue Ridge (between 3-8pm)).
Most locations will remain dry through Wednesday afternoon given the
timing of the front and residual dry air to punch through as the mid-
level ridge slowly buckles.

Before the front arrives, expect near record warmth this afternoon
and again Wednesday. Highs today will reach into the low to mid 80s
(mid 70s mountains). Lows tonight will fall back into the upper 50s
and mid 60s. Highs Wednesday will be much warmer in the mid to upper
80s and potentially low 90s for areas south and east of DC (mid 70s
mountains).

Cooler conditions return briefly Thursday as more of a wedge like
pattern settles in. This is due to a large surface high pressure
system anchored over southern Ontario wedging south along the
eastern face of the Appalachians. Expect cloudy conditions to
prevail along with passing showers, especially across the central
and southern 2/3rds of the forecast region. Highs will return closer
to normal with most locations in the mid to upper 60s. The CAD will
quickly erode Thursday night into Friday as winds switch back
to the south/southwest ahead of the next front heading into the
weekend.

KEY MESSAGE 2...A strong cold front moves through on Friday, bringing
strong winds, the potential for thunderstorms, and then cold
conditions in its wake for this weekend.

A potent shortwave trough will approach from the Great Lakes on
Friday. A strong area of low pressure will form just downstream of
this trough and track northeastward into the St. Lawrence Valley
over the course of the day. Southerly flow ahead of the system will
advect an unseasonably warm and humid airmass northward into the
area, with temperatures forecast to climb into the 80s and dewpoints
reaching into the 60s. The system`s cold front will move through the
area Friday afternoon into Friday evening. The front will move into
an environment with around 500-1000 J/kg of instability, so a line
of thunderstorms may ultimately form along the front. If
thunderstorms were to form, they may be capable of producing
damaging winds, given the strong winds that will be in place just
above the surface (around 40-45 knots at 850 hPa). Regardless of
whether storms form or not, strong northwesterly winds are expected
behind the system`s cold front late Friday through Friday night and
into early Saturday morning. Frequent gusts of 30-40 knots appear
likely across the area in northwesterly flow, and some locations may
even see some gusts above 40 knots. The Alleghenies and Blue Ridge
appear to be the most likely locations to reach Wind Advisory
criteria of 40 knots.

Strong cold advection will also accompany the gusty winds, with 850
hPa temperatures plunging from in excess of 15C Friday morning to
below 0C by daybreak Saturday. Some upslope rain showers appear
likely Friday night in the Alleghenies, and some snowflakes may even
mix in by late Friday night. Air temperatures are forecast to dip
into the 40s for most Friday night, with 30s in the mountains. By
daybreak Saturday, wind chills will be in the 30s at lower
elevations, and 20s in the mountains. Northwesterly winds will
gradually decrease through the day Saturday, with temperatures
forecast to climb into the 50s (40s mountains). High pressure will
build overhead Saturday night, resulting in clear skies and calm
winds within what will already be a cool background environment.
This will be a near ideal situation for radiational cooling. With
dewpoints forecast to be in the 20s and lower 30s, it appears as
though a freeze may be possible for many locations, especially to
the west of the Blue Ridge. At least frost appears likely just about
everywhere, and freezing temperatures could encompass the entire
area outside of the immediate downtown areas in DC/Baltimore if
cooler solutions were to verify. Frost/Freeze headlines will likely
eventually be needed for much of the forecast area.

Quiet weather conditions and a gradual warming trend in temperatures
are expected for Sunday and Monday as high pressure moves offshore.
High on Sunday and Monday will generally be in the 60s (50s
mountains), with overnight lows in the 30s and 40s.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
VFR conditions expected this afternoon through Wednesday afternoon
as weak high pressure resides nearby. A front will drop into the
area from the north late Wednesday afternoon and evening bringing
with it scattered showers and thunderstorms. This will lead to brief
sub-VFR reductions between 20-03z/4-11pm. Overall confidence for
thunderstorm activity over the I-95 corridor terminals is less than
25 percent with higher thunderstorm probabilities of 25 percent or
greater mainly west of MRB. The front drops south of the region
Thursday before stalling in the vicinity of southeast and southwest
VA. This will put us in more of a wedge-like pattern with on and off
showers and widespread sub-VFR (cigs) conditions at most of the
terminals. Winds will remain out of the south today at 5 to 10 kts
with occasional gusts up to 20 kts. South winds continue tonight
into Wednesday at less than 10 kts. Did mention LLWS along and west
of MRB and SHD tonight 2KFT AGL at 35 kts. Winds will switch to the
north and northeast Thursday at less than 15 kts in the wake of the
frontal boundary.

VFR conditions and gusty south to southwesterly winds are expected
Friday morning. A strong cold front will move through Friday
afternoon. A line of thunderstorms could potentially accompany the
front, leading to a brief period of sub-VFR conditions. Strong
northwesterly winds are expected behind the front late Friday
afternoon through Saturday morning, with gusts of 30-40 knots
possible at times. Continued VFR conditions are expected on
Saturday, with winds remaining out of the northwest, but gradually
decreasing in magnitude throughout the day.



&&

.MARINE...
South winds around 10 to 15 knots are expected today across the
waters. Southerly channeling effects could bring gusts close to
SCA levels (around 20 knots), but this likely won`t be for a
long enough period to require a Small Craft Advisory. Instead,
Marine Weather Statements are more likely to be issued for small
crafts to exercise caution.

Winds diminish tonight into Wednesday, with generally sub-SCA
conditions. A front moves south across the waters Thursday morning,
and this is likely to bring SCA conditions with gusts around 20
knots for several hours. Winds do quickly diminish Thursday
afternoon.

SCA level winds appear likely in south to southwesterly flow Friday
morning. A strong cold front will move through Friday afternoon into
Friday evening. A brief line of thunderstorms may accompany the
front. Winds shift to northwesterly behind the front, and Gale
conditions appear likely along/behind the front Friday evening into
early Saturday morning. Winds will remain northwesterly on Saturday,
but gradually decrease in magnitude through the day.

&&

.TIDES/COASTAL FLOODING...
South winds on Wednesday could result in elevated water levels at
sensitive locations along the Chesapeake Bay. This could result in
several stations reaching Action Stage, with Annapolis and Havre
de Grace forecast to be closer to minor tidal flooding during
the Wednesday morning high tide. A surge of offshore (north)
winds Thursday morning will bring water levels back down.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

DISCUSSION...KJP/EST
AVIATION...KJP/EST
MARINE...KJP/EST

NWS LWX Office Area Forecast Discussion