363
FXUS61 KLWX 061932
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
332 PM EDT Thu Aug 6 2026
.WHAT HAS CHANGED...
Made a few minor changes to the aviation section to speak to
the low clouds this morning, particularly over IAD. Also altered
the marine section slightly. Overall though, forecast remains on
track over the next several days.
&&
.KEY MESSAGES...
- 1) Hot, humid conditions persist into next week, along with
daily chances for shower and thunderstorms.
- 2) Patchy dense fog will be possible over the next several
mornings.
- 3) A cold front could arrive late in the week,
potentially bringing a pattern change into next weekend.
&&
.DISCUSSION...
KEY MESSAGE 1...Hot, humid conditions persist into next week,
along with daily chances for shower and thunderstorms.
A very repetitive weather pattern has set up for the next
several days, characterized by warm and humid air from offshore
high pressure and continued impulses of upper level energy. This
will yield showers and storms each day through at least early
next week, and likely even beyond.
Starting with today, numerous storms are developing along the
lee trough, as well as a few along the Chesapeake Bay Breeze.
The environment is characterized by around 2000-3000 J/kg of
MLCAPE, but very weak shear (around 20 knots). This is yielding
a few strong storms, but very few that are able to maintain
themselves for very long. This is also likely due to meager
mid-level lapse rates around 5 C/km. This will continue to be
the story through this evening. Latest mesoanalysis also depicts
around 400-600 J/kg of DCAPE, which coincides with max
downdraft velocities around 60 mph or so, which is about what is
being seen in the strongest of storms. Expect this threat to
remain pretty isolated, with most storms through the evening
producing primarily heavy rainfall, frequent lightning, and
gusts around 40 mph. Torrential rainfall rates can be expected
at times, with PWATs in excess of two inches currently across
much of the area. Storms will gradually come to an end this
evening as they rain themselves out after sunset.
Friday looks somewhat similar to what we are seeing today,
albeit with slightly more shear/forcing. A slightly more potent
piece of energy looks to move across the area during peak
heating. This should yield deep-layer shear values closer to 30
knots perhaps. There will be a similar thermodynamic environment
in place, with high amounts of CAPE, but DCAPE values similar or
even a bit less than today. One thing to watch for though is
that, thanks to the shortwave, mid-level lapse rates will be in
the 6-7 C/km range tomorrow afternoon, which could lead to a
higher coverage of stronger updrafts. This would then allow more
storms to potentially tap into that peak downdraft potential and
yield a few more severe storms than we see this afternoon. Would
also expect to see some large hail as well, given the higher
lapse rates aloft. A Marginal Risk is maintained from the Storm
Prediction Center.
Beyond Friday, this pattern likely continues through at least
the early and middle portions of next week. South to
southwesterly flow is maintained over the Mid-Atlantic. Hot and
humid conditions each afternoon, with highs reaching the upper
80s to low 90s, and heat indices in the low 100s each of the
Blue Ridge. Scattered showers and thunderstorms each afternoon.
Deep layer shear is forecast to increase through the weekend as
the subtropical jet stream strengthens. On Saturday, a more
potent shortwave trough is forecast to move overhead that could
aid in stronger, more organized severe convection. Damaging wind
gusts will be the main threat.
A quasi-zonal flow aloft will develop Sunday into into next week.
Sunday could bring a short reprieve as dry conditions prevail.
However, seasonably hot and humid conditions continue, and
should quickly bring showers and storms back into the forecast
Monday through most of next week.
KEY MESSAGE 2...Patchy dense fog will be possible over the next several
mornings.
With daily showers and thunderstorms, and warm/humid overnights,
patchy dense fog can be expected each morning. The location
will be difficult to pinpoint, with areas that receive rain the
day prior the likely candidates.
KEY MESSAGE 3...A cold front could arrive late in the week,
potentially bringing a pattern change into next weekend.
While this is very far out in the forecast period, there is some
signal that a more potent frontal system could push through the
region late in the week. The details are murky at this stage of
the forecast, with timing very uncertain, as well as potential
impacts. Guidance is generally between Thursday/Friday right
now, with improvement in the weather pattern possible
thereafter. Any decent frontal passage in the summer time should
be watched closely for potential severe weather, so we will
keep monitoring this in the coming days to see if that potential
is there, and try to narrow down the timeframe a bit more.
&&
.AVIATION /19Z THURSDAY THROUGH TUESDAY/...
VFR conditions across most terminals at this time, with the
exception being those that get storms through this evening. IAD,
CHO, and DCA are under the biggest threat currently. However,
storms will move east, potentially impacting BWI and MTN again
later this afternoon/evening.
VFR conditions prevail for most of the time through early next
week. South to southwest winds prevail for the foreseeable
future as the Bermuda high persists across the western Atlantic.
Daily chances for showers and thunderstorms each afternoon and
evening through the middle of next week, which could result in
periods of restrictions at affected terminals.
&&
.MARINE...
Small Craft Advisories could be needed for parts of the waters at
times through Saturday, mainly in the late afternoon to evening.
Most days will be marginal, and likely handled by MWSs, but just
know it could get a bit breezy over the open waters each
afternoon. Otherwise, winds remain around 10 knots. Daily
showers and thunderstorms expected each afternoon into next
early week. Special Marine Warnings would accompany any of the
stronger thunderstorms capable of producing frequent lightning
and wind gusts over 35 knots.
&&
.TIDES/COASTAL FLOODING...
Anomalies climb late this week in response to return southerly flow.
Periods of coastal flooding are possible at times of high tide at
sensitive locations.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.
&&
$$
DISCUSSION...CJL/KRR
AVIATION...CJL/KRR
MARINE...CJL/KRR
NWS LWX Office Area Forecast Discussion