194
FXUS61 KLWX 020047
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
847 PM EDT Mon Sep 1 2025

.SYNOPSIS...
Surface high pressure centered to the north slowly drifts eastward
through midweek. A low pressure system and associated cold front
tracks towards the forecast area from the Great Lakes region
Wednesday before moving through on Thursday. A secondary cold front
moves through Thursday night and into Friday morning. High pressure
returns for the weekend.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
With exception to an isolated shower over southern Maryland and
parts of the Tidal Potomac for another hour or two, skies will
become mainly clear overnight. Low temperatures will drop into
the 50s and 60s with higher elevations dropping into the 40s.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH WEDNESDAY NIGHT/...
Dry conditions Tuesday as surface high pressure remains
overhead. Shortwave energy pivoting aloft will bring a slight
chance of precip to those in southern Maryland and along the
Chesapeake Bay once again. Dry air will inhibit most
precipitation, but an isolated shower cannot be ruled out.
Temperatures remain below normal with highs forecast in the 70s
for most. Those in the metro areas may rise into the low 80s
while those at higher elevations stay in the upper 80s.
Overnight low temperatures Tuesday into Wednesday will be in the
50s across most of the area with only those in the metros
staying in the 60s.

On Wednesday, surface high pressure shifts offshore bringing a
change in wind direction as wind shifts southerly. This will usher
in moisture leading to increasing cloud cover, dew points, and
precipitation chances. A shortwave trough aloft will bring a slight
chance to a chance of rain showers to areas west of the Blue Ridge
in the afternoon with surface high pressure keeping the rest of the
area dry. Temperatures warm slightly with more areas east of the
Blue Ridge reaching the low 80s.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
An anomalous upper low centered south of Hudson Bay will wobble
eastward on Thursday and Friday before accelerating off to the east
thereafter. As this system translates eastward, a series of embedded
shortwaves are expected to swing through the Great Lakes and
northeastern U.S. The overall trajectory of these impulses largely
graze the area with stronger height falls closer to the
international border with Canada. The day-to-day model trends have
been showing a slower progression of the cold air that arrives
behind the synoptic-scale trough. However, this reinforcing shot of
cooler air does make it into the area by late in the weekend into
next Monday.

The best chance for any showers and thunderstorms would be Thursday
afternoon/evening with the approach of a cold front. While not
necessarily providing much of a drop off in temperature, it does
enhance low-level convergence. Instability is modest at best which
should temper a larger scale thunderstorm threat. However, a few of
the more robust updrafts could become strong to severe in nature.
This boundary eventually slides east of the area by early Friday. As
mentioned, any temperature falls do not really take shape until the
secondary surge over the weekend. Spotty showers may also accompany
this trailing cold front that tracks through on Saturday. While high
temperatures should be in the upper 70s to mid 80s through Saturday,
temperatures fall back down into the mid/upper 70s to finish out the
period.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
VFR conditions continue overnight. Northeast winds will diminish
overnight. Patchy fog is possible overnight, mainly at CHO and
MRB where low level moisture is greatest. Light winds out of the
northeast are expected Tuesday. Winds light and variable
overnight before shifting to southerly on Wednesday as high
pressure shifts offshore. VFR conditions continue Wednesday as
winds gust 5 to 10 knots.

With a threat of showers and thunderstorms on Thursday, some
afternoon/evening restrictions are possible at all TAF sites.
Initial winds ahead of the cold front will be out of the south and
gust up to 20 to 25 knots. The boundary pushes off to the east late
Thursday with winds turning more southwesterly. A secondary cold
front moves through on Saturday which could bring a few showers with
it. Otherwise VFR conditions are expected on Friday into Saturday
with winds shifting to westerly behind this next frontal system.

&&

.MARINE...
Winds diminish overnight and are expected to remain light on
Tuesday, gusting less than 10 knots. On Wednesday, high pressure
shifts offshore and winds shift to southerly. Winds gust around
10 knots in the Chesapeake Bay Wednesday afternoon. Winds
remain below SCA criteria through midweek with no other marine
hazards expected.

Ahead of a cold front, southerly channeling will likely increase
gusts over the waters on Thursday. Small Craft Advisories may be
required Thursday afternoon into Thursday night. Showers and
thunderstorms accompany the front that moves through. Cannot rule
out a Special Marine Warning or two for any of the more potent
cells. Behind the front, winds generally remain out of the south to
southwest. Winds could approach advisory levels at times on
Friday.

&&

.TIDES/COASTAL FLOODING...
Water levels may fluctuate a bit through Tuesday as
northeasterly to easterly winds fluctuate in strength. Annapolis
may come close to reaching minor flood stage by tonight`s and
Tuesday night`s high tide, but confidence is low. A flip to
southerly flow Wednesday should allow for further rises in water
levels. Confidence in Annapolis reaching minor flood increases
Wednesday night. Peak water anomalies appear to occur Thursday
night ahead of a front. More locations may reach minor flood,
and some guidance has Annapolis approaching moderate flood.

&&

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

&&

$$

SYNOPSIS...AVS
NEAR TERM...AVS/KLW
SHORT TERM...AVS
LONG TERM...BRO
AVIATION...BRO/KLW
MARINE...BRO/KLW
TIDES/COASTAL FLOODING...KLW