Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

697
FXUS61 KLWX 280735
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
335 AM EDT Tue Jul 28 2026

.WHAT HAS CHANGED...
A Flood Watch is in effect for northeast Maryland as strong to
severe thunderstorms capable of producing torrential downpours
impact the area this afternoon and into the evening. There is a
Slight Risk from SPC with damaging wind gusts, large hail, and a
brief tornado possible in strongest storms.

&&

.KEY MESSAGES...
- 1) Slight Risk of severe thunderstorms today as a strong cold
 front impacts the forecast area.

- 2) A few chances for rain through the weekend, but no
 hazardous weather expected between Wednesday and Sunday at this
 time.

&&

.DISCUSSION...

KEY MESSAGE 1...Slight Risk of severe thunderstorms today as a
strong cold front impacts the forecast area.

A potent surface low pressure system tracks east from the Great
Lakes region towards New England today with the associated cold
front pushing across the forecast area later today. This strong cold
front, combined with a deep upper level trough digging across
eastern CONUS, leads to an increased chance of scattered severe
thunderstorms this afternoon and into the evening. Showers and
thunderstorms increase in coverage between 2PM and 8PM with storms
lingering later in the southeastern portions of the forecast area.
Multiple bowing and linear segments are possible with damaging wind
gusts as the primary hazard type. That being said, cooling mid-level
temperatures contributes to a threat of large hail and a brief
tornado is possible due to low-level shear. The Storm Prediction
Center has the majority of the forecast area (with the exception of
western Maryland being in a marginal risk) in a slight risk for
severe weather.

In addition to the severe weather threat, a moist airmass with PWATS
exceeding 1.7 inches makes strong thunderstorms capable of producing
torrential downpours. Where PWATS and ensemble QPF
probabilities are highest, a Flood Watch is in effect from 8AM
this morning to 2AM early Wednesday morning in northeast
Maryland. The most vulnerable locations would be urbanized areas
along I-95 as well as areas which have experienced heavy
rainfall in recent days. Recent HREF probabilities have slightly
shifted the bullseye of QPF maxima eastward, so kept the Flood
Watch northeast of the DC metros although an expansion may be
needed later should future guidance indicate an increased risk.

In the wake of the frontal system, surface high pressure builds over
the area from the west with slightly cooler and drier conditions
expected Wednesday and Thursday.

KEY MESSAGE 2...A few chances for rain through the weekend, but no
 hazardous weather expected between Wednesday and Sunday at this
 time.

The upper-low over the northeast CONUS will linger through Friday
before finally pulling off to the northeast. As a result, there will
be non-zero rain chances each day, primarily areas further north and
east. Friday could be dry for all, but still a bit of uncertainty
regarding exactly when the upper low departs.

A broad upper-level trough will begin to form over the Ohio River
Valley over the weekend. As this trough tracks east, cloud cover &
precipitation chances will begin to increase, particularly between
Saturday evening and Sunday as the low tracks offshore and towards
the northeast. Severe probabilities look low at this time, with a
pretty weak wind field aloft. Nonetheless, weekend showers are
possible with this system should the synoptic setup continue to
trend toward development over the Midwest.


&&

.AVIATION /07Z TUESDAY THROUGH SATURDAY/...
A strong frontal system brings showers and thunderstorms to the
terminals on today. Sub-VFR conditions are expected both this
morning during showers and thunderstorms and later in the afternoon
as strong to severe thunderstorms track across the forecast area.
Strong wind gusts, low ceilings, reduced visibilities, heavy rain,
and frequent lightning are all possible in the afternoon. Sub-VFR
conditions continue into Wednesday morning depending on how slowly
the front tracks offshore. Winds gust 15 to 25 knots out of the
northwest. Prevailing VFR conditions are expected across terminals
Thursday with 10-15 knot winds gusting up to 20 knots before
diminishing overnight.

VFR conditions are expected on Friday. However, an upper-low to our
northeast could bring some showers close to BWI/MTN. This is a very
low likelihood scenario at this time, but can`t completely rule it
out. Either way, no significant reductions appear likely at this
time.

Saturday and Sunday appear to be days with occasional showers
possible, but VFR conditions otherwise.

&&

.MARINE...
Winds increase through this morning with Small Craft Advisories in
effect through tonight. Active convection will also make for
hazardous conditions across the waterways with SMWs likely.
This may include strong winds, abrupt wind shifts, and frequent
lightning. Winds shift to northwesterly overnight into Wednesday
with SCA criteria winds likely throughout the day. Small Craft
Advisory conditions continue through Friday morning.

Winds will drop below SCA criteria for Friday and continue for much
of Saturday. However, as winds turn southerly late Saturday
afternoon/evening, winds could approach SCA criteria as they channel
up the Chesapeake Bay.

&&

.TIDES/COASTAL FLOODING...
Southerly winds this morning combined with a full moon keep
tidal anomalies elevated through midweek. Annapolis is forecast
to reach minor flood stage during the high tide cycle this
morning and again late tonight. Many tidal locations are
forecast to reach action stage through Thursday morning before
tidal anomalies slowly decrease.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Flood Watch from 8 AM EDT this morning through late tonight
     for MDZ006-008-011-014-506>508.
     Small Craft Advisory from 8 AM this morning to 8 PM EDT this
     evening for MDZ008.
     Coastal Flood Advisory until 8 AM EDT this morning for MDZ014.
VA...None.
WV...None.
MARINE...Flood Watch from 8 AM EDT this morning through late tonight
     for ANZ530.
     Small Craft Advisory from 8 AM this morning to 8 PM EDT this
     evening for ANZ530>533-537>542.
     Small Craft Advisory from 8 AM this morning to 6 AM EDT
     Wednesday for ANZ534-543.
     Small Craft Advisory from 1 PM this afternoon to 8 PM EDT this
     evening for ANZ535-536.

&&

$$

DISCUSSION...AVS/CJL
AVIATION...AVS/CJL
MARINE...AVS/CJL