576
FXUS61 KLWX 101424
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1024 AM EDT Thu Jul 10 2025

.SYNOPSIS...
A weak front will remain north of the area through Friday. Weak
high pressure will build over the area Saturday, then another
front may drop southward toward the area Sunday. This cold front
tracks through the region early next week before stalling off to
the south.

&&

.NEAR TERM /THROUGH TONIGHT/...
While the primary synoptic boundary is currently analyzed over
southern New York back across Lake Erie, another more subtle
mesoscale boundary is evident over the local area. While being
more a dew point gradient, some degree of frontal zone is noted
just north of the Mason-Dixon Line. To the south, dew points are
mainly in the low 70s, with low/mid 60s across much of
Pennsylvania.

Within this warm/moist sector, a thick band of low stratus
continues to blanket the region. While any early morning patchy
fog has largely mixed out, the low clouds appear here to stay
thus far. The 12Z KIAD sounding and recent aircraft soundings
show a very saturated air mass with precipitable water values
just above 2 inches. With very light winds in the low-levels, it
may take some time to fully scour out the thick cloud cover.

There is some uncertainty with coverage of showers through the
morning, as a few models show fairly extensive coverage of light
rain developing, while a larger number just have a few
scattered showers, mainly south and east of DC. This could have
some effect on heating, although with moist southwest flow
remaining in place, few breaks in the clouds will likely occur
until afternoon, generally progressing from southwest to
northeast. With the cloud cover and temperatures only rising
into the lower to mid 80s, instability will be much less than
previous days. The fact that the trough axis will be moving
overhead in the moist environment likely mean that at least some
scattered showers and storms will develop, but severe weather
looks unlikely. The greatest coverage will likely be along the
southern and western periphery of the CWA where there will be
more sun. Precipitable water values will be around 1.5-1.8
inches west of the Blue Ridge and closer to 2 inches to the
east, so there is still some threat of heavy rain due to slower
storm motions. However, due to the lower coverage and lower
instability in place, the flooding threat should be more
isolated today. If there is one area to key in on, it would be
Nelson and Albemarle, where greater storm potential intersects
saturated ground. Will continue to monitor the need to
coordinate a watch in this area.

With the trough axis and deeper moisture progressing to the east
tonight, rain chances should quickly decrease and there may be
some clearing. There`s a signal in guidance for fog to develop,
and some could be locally dense. Lows will be in the mid 60s to
lower 70s.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Subtle ridging will begin to build Friday, and the surface
front/trough will become increasingly diffuse. More sunshine
will allow temperatures to bump upward into the mid 80s to lower
90s. Without a strong trigger, convective development will
likely be tied to the terrain, though scattered activity could
form elsewhere, especially closer to the river/bay breezes.
Low shear will limit the severe threat, though moderate
instability and some drying aloft may support a few pulse
downbursts. Precipitable water values will also trend down, but
slow storm motions on saturated soils could result in an
isolated instance of flooding. However, the pulsey nature of
storms will likely limit their residence time. Fog may develop
again Friday night.

Ridging aloft builds further Saturday. The surface pattern
remains ill defined in the weak gradients, but weak surface high
could be implied. There will also be a weak backdoor boundary
which may attempt to approach between high pressure over New
England and a low off the coast. With all that said, the
forecast is not that much different than Friday without a
notable feature to focus storm development. Generally scattered
coverage is expected with an isolated flood threat remaining
possible for any slow moving storms over saturated grounds.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
A typical summertime pattern will persist across the area through
the middle of next week, with seasonable heat and humidity, as well
as chances for thunderstorms each afternoon and evening.

On the synoptic scale, the pattern is expected to change very little
over the course of the long term period, with the stronger belt of
westerlies staying well to our north, and no strong frontal passages
to speak of. While there will be chances for showers and
thunderstorms each afternoon, the greatest coverage of storms will
likely occur on Monday as a shortwave disturbance aloft moves
through, providing a bit more large scale forcing for ascent. Ample
sunshine is expected through the morning hours each day. High
temperatures are expected to rise into the upper 80s to around 90
each day, with overnight low temperatures in the mid-upper 60s to
the west of the Blue Ridge, and then lower to middle 70s further
east.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
The low ceilings across the region have been slow to erode thus
far amidst a very moist and saturated atmosphere. However, these
should gradually lift through the late morning and early
afternoon. Some scattered showers will also be possible but
should not carry additional impact. The longer residence time of
the clouds may hamper thunderstorm development today. Included
a PROB30 group for DCA/IAD/MRB for the late afternoon, but it`s
definitely at the lower end of the probability spectrum. BWI/MTN
may just see some lingering showers. There is a greater chance
of storms at CHO, however. This threat rapidly diminishes during
the evening, with a pretty strong signal for fog the second
half of the night as skies start to clear. Some locally dense
fog can`t be ruled out.

Friday and Saturday will be similar that afternoon/evening
convection will be more scattered in nature and should be brief
in nature. Patchy fog, or possibly lower ceilings could develop
during the overnights/early mornings.

Prevailing VFR conditions are expected on both Sunday and Monday,
but showers and thunderstorms may lead to brief restrictions either
afternoon or evening. Winds will be light out of the south on
both Sunday and Monday.

&&

.MARINE...
Light background winds are expected today through Saturday.
Prevailing direction will start southwesterly but become
southeasterly over the next few days. With the light flow, local
variations will occur. The main threat will come from gusty
thunderstorms each afternoon and evening, but overall that
threat should be more scattered in nature compared to Tuesday
and Wednesday.

Sub-SCA conditions are expected over the waters on both Sunday and
Monday, with light southerly winds both days. Thunderstorms may be
possible during the afternoon and evening hours, potentially leading
to the issuance of SMWs.

&&

.TIDES/COASTAL FLOODING...
Over the course of the next few days, water levels slowly become
more elevated in time. This carries some of the more sensitive
locations into Action stage, particularly during the higher of
the two astronomical high tide cycles. The Stevens Ensemble
system supports this gradual uptick in anomalies into the
weekend.

&&

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

&&

$$

SYNOPSIS...ADS/BRO
NEAR TERM...ADS/BRO
SHORT TERM...ADS
LONG TERM...KJP
AVIATION...ADS/BRO/KJP
MARINE...ADS/BRO/KJP
TIDES/COASTAL FLOODING...