Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

967
FXUS61 KLWX 130800
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
400 AM EDT Wed May 13 2026

.WHAT HAS CHANGED...
Forecast thinking largely remains on track, although SPC has
expanded the Marginal Risk for severe thunderstorms slightly
eastward. Small Craft Advisories were extended into this
evening.

&&

.KEY MESSAGES...
1) Gusty thunderstorms are possible this afternoon and evening.

2) Above average temperatures are likely for the weekend into
early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Gusty thunderstorms are possible this afternoon
and evening.

Low pressure is located over Lake Huron this morning, with high
pressure situated off the Mid Atlantic coast. Due to the
gradient between these features, steady SE or S winds are
already in place for many areas, and will only increase with
mixing after sunrise. Some gusts up to 30 mph are possible
today. Currently showers are located across the Ohio Valley well
ahead of the surface cold front. This lead disturbance will
cross the area later this morning through the afternoon, quickly
increasing cloud cover. While an embedded rumble of thunder is
possible, instability will largely be lacking with this first
round. Combined with residual dry air in place and showers
outrunning the forcing, it`s possible they greatly diminish by
the time they reach the I-95 corridor in the afternoon. The
current high temperature forecast is well into the 70s for most
locations, but it could turn out cooler depending on the
coverage of rain and clouds with this first round.

A second round of showers and thunderstorms is then forecast to
form in the upper Ohio Valley ahead of the cold front in the
afternoon. There will be only a few hours for the atmosphere to
recover from the previous showers, so instability will likely be
limited. However, forcing, moisture, and shear will be present,
so some stronger storms could still develop as the axis moves
eastward across the Appalachians during the late afternoon or
early evening. Strong outflow winds will be the main threat with
any stronger storms/linear segments. With sunset and weaker
antecedent instability east of the Blue Ridge Mountains, it
appears thunderstorms will weaken, with mostly showers reaching
the I-95 corridor mid to late evening. Most locations are
expected to receive less than a half inch of rain, and it`s
possible some could miss out altogether. Some residual showers
could linger until the cold front passes late, and upslope rain
showers will start in the Allegheny Mountains. If any clearing
can occur between the main rain and the wind shift to northwest,
some fog may develop.

Upper level low pressure will pivot over the northern Mid
Atlantic on Thursday while surface low pressure redevelops over
New England. This will result in gusty northwest winds and
plentiful stratocumulus. Rain showers appear mostly limited to
upslope areas in the Alleghenies, but can`t totally rule out an
isolated shower or sprinkle elsewhere. Temperatures will be
cooler beneath the trough as well, with most lower elevations in
the 60s. There could even be a few wet snowflakes mixed in on
the high peaks above 4000 feet Thursday morning.


KEY MESSAGE 2...Above average temperatures are likely for the
weekend into early next week.

Surface high pressure moves into the region on Friday as the
upper low pulls away, resulting in temperatures returning closer
to normal despite continued gusty northwest winds. Further
height rises on Saturday will mark a significant warm- up with
highs in the upper 80s likely across a majority of the area. A
few afternoon & evening rain showers/thunderstorms are possible
through the weekend as a shortwave trough briefly passes through,
but this will likely be focused to the mountains and areas west
of the I- 81 corridor. Drier air moves into the region on
Monday, minimizing rain chances. However, some isolated diurnal
terrain convection is possible both Monday and Tuesday. As
upper level ridging continues to build overhead, early
temperature outlooks continue to show highs in the low- to- mid
90s by next Monday and Tuesday.

Looking ahead, an upper level trough developing over the northern
Plains begins to move through the region late Tuesday, potentially
bringing additional showers and a cold front at some point in
the middle of the week.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
South winds will continue to increase through the morning, with
gusts up to 25 kt possible after sunrise. There may be multiple
rounds of showers and embedded tstorms, one during the afternoon
to early evening, and the second following a few hours later
during the evening. Instability is fairly weak with the first
round, so have left out thunder mentions, but did try to show
the break with the second round. The second round will likely be
weakening with eastward extent, so only have PROB30 TSRA at MRB,
CHO, and IAD. Any stronger storms could contain gusty outflow,
especially at MRB. Winds will likely shift to the west after the
second round of showers but be light or even calm in spots,
which could lead to fog development should any clearing take
place. However, some guidance suggest MVFR to IFR ceilings will
develop, especially over the metro terminals near and just after
showers end. A wind shift to northwest late at night should
assist in improving conditions.

An upper level low will be nearby Thursday before moving east
Friday. This will likely result in stratocumulus ceilings, with
a worst case being MVFR. Northwesterly winds will also gust 20
to 25 kt both days.

A shortwave trough coming in from the southwest could bring
scattered showers & thunderstorms during the Saturday and Sunday
afternoon/evening timeframe at KCHO and KMRB, but VFR
conditions are otherwise expected. Light winds shift southwest
Saturday afternoon, then flow south by Sunday evening.

&&

.MARINE...
Southerly flow has increased this morning between low pressure
in the Great Lakes and high pressure off the coast. Small Craft
Advisories are in effect for all waters through the day. Some
gusts up to 30 kt are possible. A few thunderstorms could reach
the waters this evening, but at this time the threat for Special
Marine Warnings appears low as activity should be weakening. The
SCA was extended through the evening along the bay. Winds will
be lighter for a time before the cold front brings a shift to
the northwest early Thursday morning. The length of this gap is
a bit uncertain, but advisories will definitely be needed after
sunrise Thursday with gusts to 25 kt. Gusty NW winds and
advisories will continue into Friday for some if not all waters.
Winds fall below SCA criteria by Friday evening.

Winds shift southerly on Saturday. Besides a brief period
Saturday afternoon where winds could be borderline,
winds stay below SCA criteria through the weekend.

&&

.TIDES/COASTAL FLOODING...
Water levels are gradually increasing in gusty southerly flow ahead
of a low pressure system. For the most part, peaks in action
stage are expected, with the highest tide occurring tonight.
The Stevens ensemble shows the potential for Minor tidal
flooding at Annapolis, but other guidance is just below. Expect
anomalies to fall thereafter as winds shift to northwesterly.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 1 AM EDT Thursday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 1 AM EDT Thursday for ANZ530>534-
     537>543.
     Small Craft Advisory until 8 PM EDT this evening for ANZ535-
     536.

&&

$$

DISCUSSION...ADS/SRT
AVIATION...ADS/SRT
MARINE...ADS/SRT