192
FXUS61 KLWX 220731
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
331 AM EDT Fri May 22 2026
.WHAT HAS CHANGED...
Moderate rain has developed along the stalled boundary in
Central VA, with light rain to the north. Much cooler
temperatures today as another round of showers lifts through the
region this afternoon/evening.
&&
.KEY MESSAGES...
- 1) Wet, cool pattern continues through the holiday weekend.
- 2) Daily rain chances persist into early next week, with
gradually warming temperatures.
&&
.DISCUSSION...
KEY MESSAGE 1...Wet, cool pattern continues through the holiday
weekend.
Surface high remains wedged in across the Mid-Atlantic with
overrunning rainfall early this morning along a stalled front
overhead. Dry air has worked its way south to along I-70, with a
light rain to the south of that, and moderate rainfall ongoing in
Central VA. Even so, rainfall amounts are on the order of 0.1-0.2"
in the last hour, thus not expecting flooding from this.
Later this morning a shortwave trough will lift from the Mid-South
toward the OH Valley, and this drags a surface low with it that
tracks toward the central Great Lakes. This is going to bring a
round of steady rain to the area as the stalled front lifts north,
though the better forcing looks to be just north of our area in PA.
Rainfall amounts of 1-1.5" are forecast across the area, with up to
2" possible near the PA border. Given large rainfall deficits and
severe drought conditions, the rainfall will be extremely beneficial.
Rainfall tapers off briefly this evening, especially south of I-66.
Another round of showers moves through tonight into Saturday as a
slow moving inverted trough moves up along the coast. This trough
could close off into a weak low off the Delmarva Saturday night into
Sunday. Easterly winds could gust around 20-25 mph Saturday into
Saturday night for those from Washington DC to northeast MD.
Rainfall chances are likely to be lowest on Sunday as most of the
upper forcing and frontal boundary lift away from the area.
Well below normal temperatures in the mid 50s to lower 60s today and
Saturday, then a warmup to the 70s on Sunday.
KEY MESSAGE 2...Daily rain chances persist into early next week,
with gradually warming temperatures.
The frontal zone which is currently pushing southward to the
Carolinas is expected to return to the region in time for Memorial
Day. This is in response to a building of heights as a large
subtropical ridge flexes northward from offshore of the southeastern
U.S. The consequence of this boundary nearby will increase the risk
of shower activity, and even some thunderstorms depending on the
degree of diurnal heating. Eventually this mid/upper ridge begins to
flatten in response to a series of northern stream impulses passing
by to the north. This ultimately nudges the meandering boundary off
to the south. Where this frontal system ends up settling will
determine the degree of convective threat as well as potential
warming trends. At this point, the multi-global ensemble system
favors a slow but steady warm up next week with mid 70s to low 80s
for most. Looking toward Thursday, all ensembles support a deep
upper trough digging down from the Canadian Maritimes. This will
help push the front back toward the south by late next week.
&&
.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
A stalled frontal boundary over the area this morning will lift
north as a warm front this afternoon. Sub-VFR conditions are likely
to persist through Saturday at all terminals. A steady period of
moderate showers is likely this afternoon to evening, then again
tonight into Saturday. Easterly winds gust around 20-25 knots at
IAD, DCA, BWI, and MTN Saturday. Conditions likely improve Sunday,
though still uncertain if VFR conditions return to all terminals.
A warm front gradually moves toward the area on Memorial Day which
introduces additional shower and thunderstorm chances. This would
support some restrictions at times, especially during the afternoon
to evening hours. The boundary gradually sags toward the south by
Tuesday, but with continued rain chances. This would support
additional sub-VFR conditions. Overall winds stay on the lighter
side with mainly southerly gradients.
&&
.MARINE...
SCA conditions are expected to continue through Saturday night as a
stalled front overhead lifts north today, then an inverted trough
slowly lifts north along the coast. The strongest winds are expected
Saturday morning to afternoon, with peak gusts around 25 knots.
A lull in winds with sub-SCA conditions is likely on Sunday.
Sub-advisory level winds are expected across the marine waters
through Tuesday. Gradients should remain light with mainly
southerlies on Monday before shifting back to north to easterlies by
Tuesday.
&&
.TIDES/COASTAL FLOODING...
Increasing onshore flow through the weekend is going to raise tidal
levels across the Chesapeake Bay. Annapolis could approach minor
flood stage Saturday afternoon, and most other locations approach
action stage. Winds weaken Sunday and that should allow water levels
to drop.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 AM EDT Saturday for ANZ530-538.
Small Craft Advisory until 6 AM EDT Saturday for ANZ531>534-
537-539>543.
&&
$$
DISCUSSION...KRR/BRO
AVIATION...KRR/BRO
MARINE...KRR/BRO