513
FXUS61 KLWX 071432
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1032 AM EDT Tue Jul 7 2026
.WHAT HAS CHANGED...
Monitoring a signal in the incoming model data and upstream
observations that suggests a potential heavy rain threat into
northern Virginia this evening.
&&
.KEY MESSAGES...
- 1) Another round of heavy showers and thunderstorms are
expected through this evening.
- 2) Daily shower and thunderstorm chances continue as a cold
front brings precipitation and the return of seasonable
temperatures.
&&
.DISCUSSION...
KEY MESSAGE 1...Another round of heavy showers and thunderstorms
are expected this evening.
As of 1430Z/10AM EDT, cloud breaks and heating were resulting in
towering cumulus west of I-81, near the Blue Ridge, and around
southern Maryland. These areas will likely see showers and
thunderstorms begin to develop by midday.
Underneath mainly overcast skies today, forecast highs will
range from the upper 70s to mid 80s, locally near 90 degrees
closer to the I-64 corridor. The expectation is for this front
to meander north to south, generally being repositioned by
convective-scale processes and where cloud breaks occur. A
tropical air mass remains in place with precipitable water
values staying in the 2 to 2.25 inch range. The tropospheric
flow stays on the weaker side which favors slow and rather
chaotic cell motions. Latest high-resolution models shift the
focus for more concentrated convection to along/west of U.S. 15
this afternoon. This generally marks where the Weather
Prediction Center has a Slight Risk for flash flooding today.
But, there is a growing signal for a wave to drop in from PA
tonight that could prompt heavy thunderstorms in northern VA in
similar areas that got heavy rain last night. With heavy
rainfall characterized by intense rainfall rates and a threat
for repeat/training convection, Flood Watches have been issued.
The watch may need to be expanded into NoVA. The most vulnerable
spots would be areas hit by recent heavy rainfall over the past
couple of days, as well as urban areas or areas of complex
terrain. River and stream levels began low due to ongoing
drought conditions. However, these have risen in some areas
recently which makes them more vulnerable to future flooding.
On the severe weather side of the equation, the Storm Prediction
Center features a Marginal Risk across the Shenandoah Valley
down toward central Virginia between I-64 and I-95. While
instblty and vertical shear are not terribly impressive,
moisture loaded downdrafts will be capable of producing isolated
pockets of wind damage. Once the sun goes down, any severe
threat should wane with the loss of diabatic heating.
By mid-week, the parent frontal zone is expected to reach the
Carolinas while stretching back up into the central
Appalachians. As an upstream shortwave trough continues to shear
on its eastward approach, the residual energetics from this
feature will keep convection in the forecast. Any severe threat
appears minimal, but some non-zero flood threat persists given
recent bouts of heavy rainfall. Owing to mainly east to
northeasterly surface winds, Wednesday will yield below average
temperatures with highs in the upper 70s to mid 80s, with mid
60s to mid 70s for the mountains.
KEY MESSAGE 2...Daily shower and thunderstorm chances continue as a
cold front brings precipitation and the return of seasonable
temperatures.
An approaching cold front brings showers and thunderstorms to the
forecast area Thursday into Friday. Hot and humid conditions
will lead to moderate instability. This along with modest shear
may result in at least isolated severe potential. With plenty
of moisture in the atmosphere, heavy rainfall will also be
possible. The cold front slowly pushes across the forecast area
Friday night and into Saturday with seasonable temperatures
expected in its wake. High temperatures for the weekend will be
in the upper 70s to 80s with overnight low temperates dropping
into the 60s to low 70s.
Heading into early next week, there are signs at a potentially
amplified pattern which could bring a return to storm chances.
&&
.AVIATION /15Z TUESDAY THROUGH SATURDAY/...
IFR/LIFR will likely be slow to lift with cool/moist onshore
flow. Low clouds, fog, and drizzle could stick around until
closer to 18Z. Through the day, expect a gradual improvement to
MVFR by around 17Z-19Z before reaching VFR late afternoon. Have
again kept a 6-hour PROB30 group this afternoon for CHO/MRB, and
later for the metros as convection further east would likely be
initiated from a wave dropping in from PA this evening. Another
round of low ceilings is expected tonight into Wednesday
morning. Winds turn more easterly through the day with some
diurnal showers and thunderstorms possible. Any stronger storm
could yield brief sub-VFR conditions.
Southwest winds on Thursday blow 5 to 10 knots across the terminals.
Showers and thunderstorms may result in flight restrictions with
reduced ceilings and visibilities. Winds shift to westerly on
Friday, gusting up to 15 knots in the afternoon. Showers and
thunderstorms continue to be possible Friday afternoon. Winds shift
to northwest in the wake of a frontal passage Saturday, gusting
around 15 knots in the afternoon.
&&
.MARINE...
Sub-advisory caliber winds are expected across the waters given
weaker gradients. Any hazardous conditions are likely going to
be tied to convection, lightning, and any accompanying gust
fronts/outflows. Additional thunderstorm chances are maintained
in the afternoon/evening forecast. Special Marine Warnings will
be required for any stronger convection, though most may stay
west of the waters and comes in later if it develops. The
coverage of stronger storms likely decreases into Wednesday.
Through mid- week, expect mainly east to northeasterly winds
with gusts up to around 10 knots.
Daily chances for showers and thunderstorms lead to a risk for
Special Marine Warnings Thursday and Friday. Southwest winds on
Thursday shift to westerly on Friday, remaining below SCA
criteria each day. On Saturday, winds shift to northwesterly in
the wake of a frontal passage.
&&
.TIDES/COASTAL FLOODING...
Light onshore (east to northeast flow) the next couple days
followed by southerly flow will cause rising tides later this
week. This may result in near minor flooding of vulnerable
shoreline the second half of this week.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Flood Watch through this evening for MDZ501-502-510.
VA...Flood Watch through this evening for VAZ025>030-036>040-050-
051-504-507-508.
WV...Flood Watch through this evening for WVZ050>052-055-502>504-
506.
MARINE...None.
&&
$$
DISCUSSION...AVS/BRO/DHOF
AVIATION...AVS/BRO/DHOF
MARINE...AVS/BRO/DHOF
TIDES/COASTAL FLOODING...LWX
NWS LWX Office Area Forecast Discussion