767
FXUS61 KLWX 280759
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
359 AM EDT Tue May 28 2024

.SYNOPSIS...
A reinforcing cold front will move through Wednesday night.
High pressure will build in from the Great Lakes in its wake,
and remain in control through the first half of the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
A cold front is progressing through early this morning, and
should clear the entire area prior to sunrise. It will be
another warm day, with temperatures climbing into the low-mid
80s to the east of the Blue Ridge, and upper 70s to low 80s to
the west of the Blue Ridge. The most noticeable difference
behind the front will be the decrease in dewpoints. It will feel
much less humid, with dewpoints in the 50s today, as opposed to
near 70 yesterday. Fair weather cumulus will develop in
response to daytime heating and resultant mixing. Aloft, heights
will gradually be falling as troughing builds further east from
the Great Lakes and a weak shortwave disturbance passes to our
north. A stray shower or storm may be possible this afternoon,
but most locations should remain dry. Winds will be out of the
west at around 10-15 mph, with gusts of 20-25 mph.

Any showers and/or cloud cover should dissipate after dark with
loss of daytime heating. Dry conditions and light westerly winds
are forecast overnight, with lows in the 50s for most (lower 60s
in downtown DC and Baltimore, as well as along the Bay).

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
Upper level troughing will continue to dig along the East Coast
during the day tomorrow, with a prominent shortwave rotating
through the base of the trough and passing overhead tomorrow
afternoon. With this stronger disturbance passing through,
greater coverage of showers and thunderstorms is expected,
especially during the afternoon. While it won`t rain all day,
most locations should experience multiple showers or storms
during the afternoon. Rainfall amounts won`t be overly
impressive, so there aren`t any concerns for flooding.
Instability and shear values won`t be impressive either, so
there aren`t any concerns for severe thunderstorms. Temperatures
are forecast to top out in the 70s tomorrow afternoon.

Any leftover showers and storms should quickly wind down during
the evening hours with loss of daytime heating. A reinforcing
cold front will move through the area tomorrow night. Winds will
turn northwesterly behind the front, and temperatures will drop
back into the 50s for most (40s mountains).

Yet another shortwave disturbance will descend down in
northwesterly flow from the Great Lakes toward the base of the
longwave trough on Thursday. This disturbance will lead to the
development of some clouds during the afternoon, and potentially
a few sprinkles or light showers. However, most locations should
remain dry. Winds will be out of the northwest at around 10-15
mph, with gusts up to 20 mph. Temperatures will only make it
into the low-mid 70s, with dewpoints dropping into the 40s.

Upper troughing will finally start to move off toward our east
Thursday night. As this occurs, large scale subsidence will
start to increase in the wake of the departing trough,
encouraging high pressure to start building in from the Great
Lakes. Most locations will maintain a northwest wind through
the night, which should keep temperatures in the 40s to lower
50s. However, more sheltered valley in the mountains may
eventually decouple during the second half of the night. If
those cooler mountain valleys do go calm, they would likely drop
into the 30s for low temperatures, leading to a chilly final
morning of May.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
By Friday, high pressure will continue to be situated
off to the northwest. Slightly below normal temperatures will be
common for the afternoon as a result of incoming northwest flow
across the Mid-Atlantic to finish the workweek. Abundant sunshine is
expected throughout the day with winds remaining fairly light.
Another cool night is expected Friday night with 40s to low 50s
expected for most locations. Cannot rule out some colder valleys and
sheltered locations getting into the upper 30s for a few hours.

High pressure will continue to build overhead for the start of the
weekend before moving further east later on. Mostly dry conditions
are expected for most of the weekend with a mix of sun and clouds
both days. Sunday, a few isolated showers and rumble of thunder will
be possible as an area of low pressure inches closer from the
Mississippi Valley. Highs will gradually increase from the low to
mid 70s on Friday to the upper 70s to low 80s on Sunday with winds
shifting more out of the south.

Afternoon showers and thunderstorms remain possible Monday as an
upper trough deepens from the Great Lakes. Highs will be in the mid
to upper 80s for a large portion of the area aside from the
mountains where upper 70s will be more common.

&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
Prevailing VFR conditions are expected at the terminals through
Thursday. Some fair weather cumulus will develop around FL070
this afternoon. A stray shower or storm also can`t be ruled out,
but the vast majority of locations should remain dry. Winds
will turn westerly today, and will gust to around 20 knots this
afternoon.

Continued VFR conditions are expected tomorrow, although there
will be a higher coverage of showers and storms, especially
during the afternoon. Winds will be out of the west at around
5-10 knots. A cold front will move through the area tomorrow
night. Winds will turn northwesterly behind the front, and may
gust to around 15-20 knots tomorrow night into Thursday. A stray
shower or storm can`t be ruled out Thursday afternoon, but most
locations should remain dry.

VFR conditions are expected Friday and Saturday with fairly light
winds out of the northwest both days. High pressure leans overhead
during the day on Saturday, keeping flow pretty calm.

&&

.MARINE...
Winds will turn westerly today. Gusts to around 20 knots may be
possible this afternoon into early this evening across northern
portions of the Bay, as well as the middle and upper Tidal
Potomac. SCAs are in effect for those locations from 11 AM until
7 PM. Sub-SCA westerly winds are expected tomorrow. SMWs may
potentially be needed in association with storms that move over
the waters tomorrow afternoon. A cold front will cross over the
waters tomorrow night. Winds will pick up out of the northwest
behind this front. SCA conditions may be possible in
northwesterly flow tomorrow night into the day Thursday.

Northwest flow will continue Friday into early Saturday. Sub-SCA
winds are expected for this period as the pressure gradient weakens
across the Mid-Atlantic.

&

.TIDES/COASTAL FLOODING...
Winds will turn westerly today, remain westerly tomorrow, and
then become northwesterly on Thursday. This continued offshore
flow should lead to decreasing water levels over time. However,
more sensitive locations like Straits Point and Annapolis may
hit Minor flood stage with the tide cycle this morning prior to
when offshore flow picks up. Thereafter, coastal flooding isn`t
anticipated over the next few days.

&&


.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Coastal Flood Advisory until 8 AM EDT this morning for MDZ017.
VA...None.
WV...None.
MARINE...Small Craft Advisory from 11 AM this morning to 7 PM EDT this
     evening for ANZ530>532-535-536-538>540.

&&

$$

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