143
FXUS61 KLWX 300726
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
326 AM EDT Sat Aug 30 2025

.SYNOPSIS...
High pressure will slowly drift north and northeast of the area
through the middle of next week. An upper-level disturbance may
bring a few showers to the Allegheny Mountains Sunday, but most
of the area will remain dry with below normal temperatures
through Wednesday. The next frontal system may bring higher rain
chances toward the end of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure is centered over the Great Lakes this morning
while vertically stacked low pressure is located over southern
Quebec. A secondary front/surge of drier air has resulted in a
light wind remaining in place for some areas early this morning.
A jet streak is also passing aloft, bringing some high level
clouds. For these reasons, fog development is limited, with just
some patchy fog possible in some of the western river valleys
through sunrise.

The jet streak will pivot away today, resulting in clearing
skies from northwest to southeast. A light northerly wind and
some low level cold advection will keep high temperatures in the
70s (60s for higher elevations).

Dry weather continues for tonight with widespread lows in the
50s and some 40s possible. As the surface high expands eastward,
the wind direction will become more northeast or east. There may
be enough moisture for some low clouds to form west of the Blue
Ridge due to the upslope flow. Mid and high level clouds will
increase toward dawn as a shortwave trough approaches.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The shortwave trough will pivot across the area Sunday, with
most guidance showing it closing off into a low Sunday night
into Monday. A more cold air damming-like position to the
surface high will result in an inverted trough developing along
the Appalachians. Recent guidance suggests the best convergence
and moisture will be west of the Appalachian crest. However, the
upslope flow may still result in a few showers or even a
thunderstorm across mainly Highland and Pendleton Counties
Sunday afternoon. The rest of the area will just see scattered
to broken clouds beneath the trough.

Even though the upper low will be overhead Monday, moisture will
be confined to a shallow layer at the top of the boundary layer,
resulting in scattered to broken diurnal cumulus. Low pressure
will be passing well offshore but will not be much of a factor
as the strong high to the north remains in control. Thus dry
weather will continue.

A persistence forecast works well for the continued below normal
temperatures Sunday and Monday, as highs will mainly be in the
70s and lows in the 50s. There`s a higher chance of some areas
reaching 80 on Monday.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Wedging high pressure will shift toward the southern New England
coast Tuesday into Wednesday. Meanwhile, a cold front will work east
from the Midwest and Ohio River Valley with a secondary low pressure
system set to work out of the lower Mississippi River Valley toward
the Carolina coast. The coastal low pressure system most likely
remains offshore as the cold front pushes into the area
Thursday and Friday, but this could change (and would enhance
rain chances). This is our next opportunity for rain across the
area. Rain will be much needed at this point given one of the
driest Augusts on record across the region.

As for severe weather, the threat remains low with a focus on
Thursday into Friday as the front pushes in. CSU machine learning
probs highlight 5-15 percent probs and the CIPS/NSSL probs
highlight 10 percent probs across the region. If severe
weather were to occur it would be in the form of wind and hail
given the drastically cooler airmass behind the front for the
upcoming weekend ahead. High pressure returns for the start of
the weekend with a secondary cold front to follow beyond the
long term period.

Temperatures will remain cooler than normal throughout much of next
week. Expect highs in the mid 70s and low 80s with lows in the 50s.
Mountain locations will be a touch cooler in the mid 60s and low 70s
with lows in the 40s and 50s.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
Impactful weather appears unlikely through the TAF period and
into Tuesday as high pressure builds north of the area. There
are low probabilities of patchy fog near MRB and CHO each
morning through Tuesday, but confidence is not high enough to
include in the TAF. Cumulus may be more pronounced Monday
afternoon as an upper low develops overhead. Winds will waver
between northerly and easterly but will largely remain less than
10 kt.

VFR conditions look to continue through Wednesday as high pressure
shifts toward the southern New England coast. Shower and
thunderstorm chances return late next week as a series of fronts and
low pressure systems cross the region.

&&

.MARINE...
A secondary front/pressure surge has resulted in enhanced
northerly winds, with some local gusts up to 25 kt. As that
boundary has pushed south, starting to see a decrease in winds
from north to south, as well as on the narrower tributaries.
Portions of the Small Craft Advisory end at 6 AM but may be
cancelled early. All waters should be sub-advisory by mid to
late morning.

High pressure will build north of the area over the weekend and
into next week. Weaker pressure gradients should keeps winds
less than advisory criteria as...northerly today then
northeasterly or easterly Sunday and Monday. Low pressure will
be passing well offshore Monday, but it may be far enough away
to have much of an effect on the bay.

Sub-SCA level winds continue through Wednesday as high pressure
remains nearby. The next chance for SCA conditions looks to
occur Wednesday night into Thursday with south to southeasterly
return flow behind departing high pressure and ahead of
incoming cold frontal boundary.

&&

.TIDES/COASTAL FLOODING...
A surge of northerly winds is resulting in decreasing anomalies
this morning. As winds slacken this evening, some of the water
may slosh back up the bay, but flooding is not expected. The
combination of low pressure passing offshore and easterly winds
will allow water to build starting Monday. Winds then remain
easterly then southerly through at least Thursday. This 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...Small Craft Advisory until 6 AM EDT early
this morning for ANZ530>533-536-538>542. Small Craft Advisory
until 10 AM EDT this morning for ANZ534- 537-543.

&&

$$

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

NWS LWX Office Area Forecast Discussion