210
FXUS61 KLWX 050619
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
219 AM EDT Wed Aug 5 2026
.WHAT HAS CHANGED...
Monitoring heavy showers and some thunderstorms moving north
through the area this morning. Flood Watch remains in effect
through late morning for the metro I-95 corridor from
Fredericksburg to Washington DC.
&&
.KEY MESSAGES...
- 1) Localized urban flash flooding possible this morning as
warm front lifts north.
- 2) Daily shower and thunderstorm chances are expected through
early next week.
&&
.DISCUSSION...
KEY MESSAGE...Localized urban flash flooding possible this morning
as warm front lifts north.
A stalled frontal boundary over Southern Virginia is lifting north
across our area as a warm front. A slug of deep tropical moisture is
already surging northward into the Mid-Atlantic, with PWATs analyzed
at or over 2" early this morning. Several of the 00Z high res models
indicate the potential for heavy rain amounts of 1-3" across the I-
95 metro area from Fredericksburg up to Washington DC. It will be
hard for models to show consensus on any given location since
convection will be driven by warm advection along the front, and
aided by forcing for ascent from an upper low lover the Mid-South.
If any of this heavy rain occurs over the urban sprawl around the
D.C. metro, poor drainage will support a risk of flash flooding. A
Flood Watch is in effect through 11 AM this morning for the
previously mentioned areas along I-95.
KEY MESSAGE 2...Daily shower and thunderstorm chances are expected
through early next week.
In the wake of what morning convection materializes, the models do
show a brief lull in the action. The northward pushing warm front
eventually stalls nearby before shearing out. Likewise, the upper
low across the Mid-South region begins to fill although the
reflection of this circulation still shows up across southern West
Virginia.
A deep southerly flow will continue around high pressure over the
Atlantic, ushering plenty of moisture. PWATS will be near or greater
than 2" in the valleys with 1-2" in the mountains, which is about 1-
2 SD above climo. A surface trough and shortwave energy will trigger
scattered showers/thunderstorms, but it should not be a washout
during the afternoon/evening. The main threat will be brief heavy
downpours and gusty winds. However, DCAPE and shear are on the lower
side, so the probability of severe storms is lower. If some storms
train over the same area, localized flash flooding can occur. The
pattern does favor the possibility for training convection (cloud
layer winds nearly parallel to low-level wind), but the coverage
should be isolated.
A similar pattern will hold on for Thursday and Friday while the
subtropical jet strengthens to the north and west. Therefore, more
showers and thunderstorms are likely along with the threat for
isolated instances of flash flooding and locally damaging wind
gusts. Hotter conditions may cause relatively steeper low-level
lapse rates and the wind field strengthens a bit (especially
Friday).
A quasi-zonal flow aloft will develop for the weekend into next
week, bringing more seasonably hot and humid conditions along with
daily chances for showers and thunderstorms.
&&
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
MVFR to IFR CIGs are expected to overspread all terminals this
morning as a warm front lifts north through the area. Heavy showers
and a few thunderstorms are possible at DCA and IAD, though all
terminals could get some rain this morning, with reduced VSBY
possible. Conditions do improve and return to VFR by mid afternoon,
before another round of thunderstorms could impact area terminals.
PROB30 groups are in the TAFs to account for this threat,
particularly from 20Z-24Z this afternoon/evening.
Winds shift to mainly south to southwesterly for the foreseeable
future as a Bermuda high pressure system persists across the western
Atlantic. Daily convective chances each afternoon and evening will
support convective-driven restrictions. With little change in the
upcoming pattern, this sort of forecast will likely hold for the
next several days.
VFR conditions are expected most of the time Saturday and Sunday,
but a few showers and thunderstorms are possible, especially during
the afternoon and evening hours each day.
&&
.MARINE...
A warm front lifts north across the waters today, bringing a return
of southerly winds. Small Craft Advisories could be needed for parts
of the waters at times this week, mainly in the late afternoon to
evening. Otherwise, winds remain around 10 knots. Daily showers and
thunderstorms expected each afternoon this week. Special Marine
Warnings would accompany any of the stronger thunderstorms capable
of producing frequent lightning and wind gusts over 35 knots.
Winds may approach SCA criteria Saturday and Sunday as the gradient
strengthens a bit between high pressure over the Atlantic and lower
pressure to the the north. A few showers and thunderstorms are
possible each day, especially during the afternoon and evening
hours.
&&
.TIDES/COASTAL FLOODING...
Southerly winds return today behind a warm front that lifts north
through the area. Anomalies climb again mid to late week in response
to return southerly flow. Additional periods of coastal flooding are
possible at times of high tide at sensitive locations.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Flood Watch until 11 AM EDT this morning for DCZ001.
MD...Flood Watch until 11 AM EDT this morning for MDZ013-016-504.
VA...Flood Watch until 11 AM EDT this morning for VAZ053>056-502-
527.
WV...None.
MARINE...Small Craft Advisory from 2 PM this afternoon to 8 PM EDT this
evening for ANZ533-534-543.
&&
$$
DISCUSSION...KRR/BJL
AVIATION...KRR/BJL
MARINE...KRR/BJL
NWS LWX Office Area Forecast Discussion