Area Forecast Discussion
Issued by NWS Sterling, VA

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965
FXUS61 KLWX 160750
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
350 AM EDT Mon Jun 16 2025

.SYNOPSIS...
Cool, damp, and dreary conditions kickoff the new workweek as a
stalled front remains nearby. A warm front will lift into the area
Tuesday and Wednesday allowing temperatures to rebound while keeping
a daily chance for showers and thunderstorms. Severe thunderstorms
are possible Thursday into Friday as a strong cold front crosses the
region. High pressure returns this weekend with hot and dry
conditions expected.


&&

.NEAR TERM /THROUGH TONIGHT/...
he CAD wedge continues to remain over the region today with strong
inversion this morning. This has led to a continuation of low
clouds, fog, drizzle, and passing showers across much of the region.
Outside of the low clouds, showers, and mist; the area sits in a bit
of lull (at least from heavier precipitation) within a much more
stable maritime airmass. Shortwave low pressure from last night into
early this morning continues to slowly exit east while the stalled
front remains draped over the Alleghenies southward into southwest
VA and northeast NC. Meanwhile, another ripple of shortwave energy
is spinning back across southern Ohio, western WV, and eastern KY.
This feature along with the dissipating stalled front to the south
will be the catalyst once again for showers and perhaps a few
thunderstorms across portions of the region later this afternoon and
into the evening hours. Highest coverage for shower and thunderstorm
activity today looks to be once again across the Alleghenies back
into southwest and south-central VA.

A Flood Watch has been issued for areas along and west of the US-220
corridor (i.e Garrett Co. MD south toward Pendleton Co. WV/Highland
Co. VA) from noon today through midnight tonight. These locations
received anywhere between 0.50-2" of rain yesterday which will
further aid in flooding concerns today. 00z CAMS/synoptic guidance
continues to hit this area hard for widespread convection later this
afternoon. Convective development once again appears to be
midday through roughly 7-9pm this evening. MUCAPE values will
hover between 500-800 j/kg with 0-6km shear values around 30
kts. PWATS will remain elevated between 1.2 and 1.8 inches. Warm
rain processes will once again be the theme with more
stratiform compared to convective elements due in part to the
CAD wedge overhead.

Shower and drizzle activity will slowly decrease later this morning
into midday. Cloud cover will prevail limiting highs temperatures to
the upper 60s and low 70s areawide. Locations west of the Allegheny
Front and south of I-64 may filter a break of sunshine or two
yielding highs in the mid to upper 70s.

The wedge will still be hard to scour as the front to the south
dissipates and eventually begins a slow jog back to the north as
warm frontal boundary heading into Tuesday morning. This means more
of the same with low clouds, fog, drizzle, and lingering showers at
times during the overnight and early morning period. Lows tonight
will fall back into the low to mid 60s. Values closer to 70 degrees
can be found in the Baltimore/DC urban centers, near the bay, and
south of the I-64 corridor.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The stalled surface boundary that will have lingered over the area
for several days will finally start to dissipate and lift north of
the area as a warm front Tuesday into Wednesday. Meanwhile, a subtle
upper level trough will approach from the Ohio Valley. Showers and
thunderstorms are expected to form during the afternoon hours within
a very humid airmass (surface dewpoints around 70). The risk for
severe weather is low, but not 0 with the Storm Prediction Center
highlighting a Marginal Risk (Level 1 out 5) over portions of the
Alleghenies and Shenandoah Valley/central Piedmont region. Damaging
winds look to be the main threat with storms along with localized
flash flooding. Storms should be fairly progressive, but given the
antecedent conditions and moist atmosphere at play localized
instances of flash flooding cannot be ruled out. CAPE values will
approach 2000 j/kg with 0-6 km shear values 35 to 45 kts. High
temperatures on Tuesday are expected to be reach into the upper 70s
and lower to mid 80s for most as sunshine returns. Lows Tuesday
night will fall back into the upper 60s and low 70s. FOg will be
possible during the overnight hours given the very moist airmass
overhead.

More of the same can be expected Wednesday as the warm front lifts
further north of the area. This will allow hotter temperatures to
move in along with slightly drier conditions under the influence of
west to southwest downsloping flow. Current CAMS and synoptic
guidance still hint on the threat of a few showers and thunderstorms
during the afternoon and evening hours Wednesday. This is due
largely in part to a shortwave trough ejecting east of the Ohio
River Valley. Highest probability of severe thunderstorms looks to
be west of the Alleghenies where the shortwave trough will reside.
Elsewhere, pop showers and thunderstorms are likely given the hot
and humid airmass in place. Highs Wednesday will push into the mid
to upper 80s and low 90s outside the mountains.

The lead shortwave trough works east Wednesday night into THursday
as the cold front approaches form the Ohio River Valley. Convection
over the mountains will work east as well before slowly dissipating
given the lack of instability during the overnight hours. Lows
Wednesday night will fall back into the low to mid 70s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
High pressure strengthens offshore moving into the middle of the
week, leading to south to southwesterly low-level flow and
increasing heat and humidity locally. Temperatures should reach into
the 90s on both Wednesday and Thursday. When combined with dewpoints
in the lower 70s, heat indices may approach 100 on Thursday.
Thunderstorms could have decent coverage on Thursday as an upper
trough tracks off to our north across the Great Lakes, with its
associated cold front approaching from the west. Current model
guidance suggests that ample instability and shear may be present on
Thursday, so some storms may be on the stronger side. SPC has the
area highlighted with a D4 outlook, so definitely something to keep
an eye on.

Upper troughing is expected to dig in from the Great Lakes on
Friday. Cooler and drier conditions are expected locally in the wake
of the system`s cold front Friday into Saturday before warming up on
Sunday.


&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
IFR conditions look to continue through mid-morning as a result of
low clouds, passing showers, and patchy drizzle. OVC CIGS will
continue to hover between 500-1000 feet, with pockets of sub 500
feet CIGS amongst the terminals through at least 15z/11am this
morning. CIGS may lift a bit this afternoon and evening as
additional shower activity works through. Outside of the light to
moderate shower/drizzle activity in the corridor this morning expect
the highest concentration of showers and perhaps a few thunderstorms
this afternoon to remain west of KMRB and KCHO. Convection will pop
over the mountains between 16-19z/12-3pm with a few spotty showers
further east due largely in part to onshore maritime flow. Shower
activity will filter back into the corridor late in the afternoon
and through the evening hours with the next wave of shortwave energy
pivoting through. Once again coverage will be scattered so tried to
use PROB30 groups to highlight this. Low clouds, fog, and drizzle
set up again overnight leading to additional IFR CIGS/vsbys and even
some brief periods of LIFR west of the corridor terminals. Winds
will remain out of the east and northeast today at less than 15 kts.

Sub-VFR conditions may be possible Tuesday morning, but improvement
back to prevailing VFR conditions is expected Tuesday afternoon
through Wednesday as a warm front lifts through the region. This
will finally scour out the low clouds. Temporary drops to sub-VFR
conditions may be possible in thunderstorms both Tuesday and
Wednesday afternoon, especially at terminals along and west of the
Blue Ridge.

Prevailing VFR conditions are expected Thursday. Temporary drops to
sub-VFR conditions may be possible in thunderstorms especially
Thursday afternoon and evening.

&&

.MARINE...
A stalled front will remain south of the waters through this
evening. Easterly winds around 10 knots, and likely remain sub-SCA
through the start of the week. Occasional gusts to around 20 knots
are possible at times. Low clouds and some marine fog is possible
this morning and again tonight given the moist airmass in place.
Less shower and thunderstorm activity is also expected today given
the proximity of the boundary south of the region. A warm front will
lift back across the waters Tuesday into Wednesday.

Sub-SCA level southerly winds are expected over the waters on both
Tuesday and Wednesday. An SMW or two cannot be ruled out with
scattered showers and thunderstorms during the afternoon and evening
hours.

SMWs are possible given thermodynamic and kinematic environment for
Thursday in any thunderstorm. SCA conditions likely return with cold
frontal passage Thursday into Friday.


&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Flood Watch from noon EDT today through this evening for
     MDZ501-509-510.
VA...Flood Watch from noon EDT today through this evening for
     VAZ503-504.
WV...Flood Watch from noon EDT today through this evening for
     WVZ501>503-505-506.
MARINE...None.

&&

$$

SYNOPSIS...EST
NEAR TERM...EST
SHORT TERM...EST
LONG TERM...CPB
AVIATION...KRR/EST
MARINE...KRR/EST