410
FXUS61 KLWX 311416
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1016 AM EDT Sun Aug 31 2025

.SYNOPSIS...
High pressure will slowly drift north and northeast of the area
through Wednesday. A pair of cold fronts will cross the area
Thursday into Friday. High pressure gradually builds in from the
west sometime next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Surface high pressure is centered over the Great Lakes this
morning, while longwave troughing encompasses eastern portions
of the U.S. and Canada. A shortwave over the Ohio Valley will
move over the area today, closing off into a low tonight.

After another chilly start across the region, any shallow
radiation inversions have quickly mixed out. Thus, mid-morning
temperatures have risen into the low/mid 60s, with 50s across
the higher terrain. Based on the 12Z sounding, vertical mixing
should be fairly deep as noted by the capping inversion up near
800-mb. This should promote ample warming through the day.
However, increasing cloud cover could offset some of this net
warming.

More specifically, the shortwave across the Ohio Valley will
result in an increase in clouds through the day, although there
should still be a fair amount of sunshine. Current trends
suggest greater moisture will remain southwest of the CWA, but
maintained isolated shower coverage around Highland and
Pendleton Counties as multiple CAMs indicate a few showers in
this area during the afternoon. Highs should be similar to
Saturday in the mid to upper 70s (60s in the higher elevations).

There could be some lingering clouds around tonight, but dry
weather will prevail. Some patchy valley fog is possible, though
coverage appears limited. Lows will drop back into the 40s and
50s again (with a few 30s possible in high elevation valleys).

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
The upper low will remain nearby Monday. Surface high pressure
will still be wedged southward along the Appalachians. The
trough will result in low pressure developing off the coast.
Some models indicate a slight uptick in northeast winds closer
to the Chesapeake Bay, but otherwise it won`t play a role in our
weather. Moisture will be scant, but there will be enough
shallow instability beneath the upper low for a fairly robust
cumulus field.

The upper low will either open or pivot northward Tuesday as
another shortwave dives into the mid Mississippi Valley. The
surface high will continue it`s slow eastward drift but remain
in control. Cool and dry weather continues.

There won`t be a lot of movement in temperatures Monday and
Tuesday in the relatively stagnant pattern, further evidenced in
very low model spread. A few more areas may reach 80 with each
passing day. Likewise, an increasingly marine fetch will result
in dew points slowly inching upward. Fewer areas will drop into
the 40s overnight as a result.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
The theme of broad troughing over the eastern CONUS will continue
the second half of this week before finally relenting for the
upcoming weekend. In particular, a strong shortwave/upper low will
dive into the Great Lakes Wednesday night into Thursday. This will
drive a pair of surface cold fronts across the Mid-Atlantic. Warm
advection rain chances may increase as early as late Wednesday.
Instability may be relatively weak, but increased flow through the
troposphere could result in a strongly forced line of gusty showers
and thunderstorms Thursday or Friday, especially if the fronts come
through during or shortly after peak heating. A wave of low pressure
may develop at the end of the week. After this, another large area
of cool high pressure builds in.

&&

.AVIATION /14Z SUNDAY THROUGH THURSDAY/...
High pressure continues to provide benign weather through
Tuesday. Still not seeing any strong signals for radiation fog,
though can`t rule out a few patches during the overnight periods
near MRB. A more robust cumulus field may develop Monday beneath
an upper low. Monday also offers the highest chance for some
wind gusts to around 15 kt. Otherwise wind should generally
remain less than 10 kt wavering between northerly and easterly.

VFR Wed-Thu, though brief sub-VFR is possible as early as late Wed
in WAA SHRA, and sub-VFR and gusty winds are possible Thu PM with
any SHRA/TSRA associated with strong cold FROPA. S/SE flow Wed-Thu
becomes W/NW Thu night with occasional 20 kt gusts possible.

&&

.MARINE...
High pressure will remain north of the area through Tuesday,
resulting in a northerly, to perhaps easterly at times, wind
direction. Winds should remain sub-advisory through this
evening. Low pressure will be developing off the coast tonight
into Monday. There has been an upward trend in winds, but the
timing and coverage in the potential for 20 kt gusts remains
uncertain. There may only be a brief window around southern
Maryland Monday morning, but stronger solutions suggest a more
widespread Small Craft Advisory could be needed Monday. Any
uptick in winds should subside by Tuesday as the pressure
gradient relaxes.

SCAs may be needed in enhanced S/SE flow Wed PM and again Thu PM
ahead of an approaching strong cold front. This system may bring
rain chances as early as late Wed, with gusty showers and a few
thunderstorms possible late Thu.

&&

.TIDES/COASTAL FLOODING...
Light winds have resulted in increased water levels sloshing
back up the bay. However, no flooding is forecast through Monday
morning. The combination of low pressure passing offshore and
easterly winds will allow water to build by Monday evening.
Should the higher water remain suppressed through Tuesday, a
flip to southerly flow Tuesday night into Wednesday should allow
for further rises. At some point, these increased anomalies could
result in some minor flooding during the higher high tides along
sensitive shoreline (such as Annapolis).

&&

.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...DHOF
AVIATION...ADS/DHOF
MARINE...ADS/DHOF
TIDES/COASTAL FLOODING...