902
FXUS61 KLWX 131853
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
253 PM EDT Fri Jun 13 2025

.SYNOPSIS...
A cold front is expected to stall across the region over the
weekend. Multiple rounds of convection will accompany the front
during the period. This front will move to the north as a warm
front on Tuesday. High pressure over the Atlantic will bring
hotter conditions for the middle portion of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A cold front, currently near or along I-66, will propagate
farther to the south late this afternoon and evening before
becoming stationary tonight through the remainder of the
weekend. Multiple clusters of showers are developing along the
Appalachian Front and moving toward the east. Individual
thunderstorms, some strong, are developing ahead of or within
these clusters of showers and are drifting toward the southeast.
More showers and strong to possibly isolated severe
thunderstorms are expected to develop during the warmest time of
the afternoon and linger into the middle part of this evening,
mainly along the cold front and across northern and central
Virginia and southern Maryland where SPC has this area in a
Marginal Risk for severe thunderstorms. The main threats will be
large hail, lightning, and torrential rainfall. WPC has this
same area in a Slight Risk for excessive rainfall that could
lead to flash flooding. There is currently a Flood Watch from
near Washington D.C. and areas to the southwest, south, and
southeast from 6pm to 2am tonight. Rainfall amounts could reach
1 to 3 inches with locally 4 to 5 inches. Surface based CAPE is
2500-3500 J/kg with MLCAPE of around 1000 J/kg. Wind shear has
also become a factor contributing to potential heavy
convection with values of 35 to 45 knots. Lack of cloud cover
has allowed for our high temperatures to reach the middle to
upper 80s easily with slightly lower values in the west.

Showers and strong to severe thunderstorms should dissipate or
become less numerous overnight with patchy fog or drizzle
developing in areas. Some fog may be locally dense. Lows
tonight will be in the 60s and 70s for most areas.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
A cold front will stall across the central zones of our region
through the day Saturday. An upper level low will move closer to
the area from the west. A lull in shower and any thunderstorm
activity more likely through Saturday morning with and
thereafter the fog. Another heavy round of showers and
thunderstorms is expected Saturday afternoon and evening. There
is still some uncertainty as to exactly where this will setup,
but latest guidance continues to suggest areas south and west of
the Potomac River as the areas most likely to get the strongest
convection. All the ingredients are there for a flash flood
threat. Will continue to monitor, because the position of the
front will be vitally important as to exactly where the
strongest convection will be. For areas to the northeast of the
boundary. A few showers and a thunderstorm are still possible,
especially late in the day into the evening as stronger
convection upstream propagates into the area.

The upper level low will shear apart as it moves into the area
Sunday, but latest guidance shows the boundary pushing a little
farther south and west. This is most likely in response to
subsidence associated with a departing jetmax in the northern
stream, causing high pressure to strengthen off the New England
Coast. The threat for heavy rain is most likely across central
Virginia into the Allegheny Highlands, but that can change if
the location of the front is off. Will continue to monitor.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
The stalled front will remain nearby in our region through the
day on Monday with cool marine air remaining in place for most
areas. The boundary will dissipate and move north Tuesday as a
warm front and high pressure over the Atlantic will likely
control the weather pattern for the middle of next week with a
return of hotter and humid conditions. Unsettled conditions will
likely persist during this time with chances for showers and
thunderstorms. Perhaps the best chance for stronger storms will
be Thursday as a cold front approaches from the west.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions will continue through much of the rest of the
afternoon. Showers and thunderstorms will increase in coverage
through this evening. A few stronger storms are possible with
gusty winds and brief IFR conditions. The best chance for
stronger storms is between 23Z and 04Z. Incorporated the
potential for heavy thunderstorms between 00Z and 03Z with a
TEMPO group.

Low clouds and areas of fog/drizzle are likely to develop late
tonight behind a stalling front that moves into the area. There
is still some uncertainty as to exactly where the boundary will
set up, but latest indications are that most areas will end up
in the marine air for Saturday through Monday. This means that
low clouds and subVFR conditions are likely most of the time
with IFR/subIFR conditions possible, especially at night into
the morning hours each day. Unsettled conditions will continue
with the likelihood for showers and perhaps a few storms. The
best chance for storms will be around KCHO, KMRB and KIAD
Saturday afternoon and evening and KCHO for Sunday afternoon and
evening. However, storms are possible everywhere.

More low clouds and fog will likely hang around through Tuesday
morning, but cigs/vsbys should improve as the backdoor boundary
dissipates and moves northward.

&&

.MARINE...
A southerly flow will increase into this evening, but winds
should remain below SCA criteria. Thunderstorm coverage will
increase through this evening. Gusty winds associated with
storms may warrant Special Marine Warnings.

A stalling front will slide across the central areas for later
Saturday through Monday night. An easterly flow will bring low
clouds and areas of fog, and the likelihood for showers and
perhaps a thunderstorm will persist. Winds should be below SCA
criteria. The boundary will dissipate Tuesday and a southerly
flow will develop for the middle portion of next week.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Flood Watch from 6 PM this evening to 2 AM EDT Saturday for
     DCZ001.
MD...Flood Watch from 6 PM this evening to 2 AM EDT Saturday for
     MDZ013-016-017-504.
VA...Flood Watch from 6 PM this evening to 2 AM EDT Saturday for
     VAZ037>039-050-051-053>057-502-527.
WV...None.
MARINE...None.

&&

$$

SYNOPSIS...BJL
NEAR TERM...KLW
SHORT TERM...KLW
LONG TERM...BJL
AVIATION...BJL/KLW
MARINE...BJL/KLW