Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

786
FXUS61 KLWX 291422
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1022 AM EDT Sat Aug 29 2026

.WHAT HAS CHANGED...
No changes to the forecast at this time.

&&

.KEY MESSAGES...
- 1) Cooler and less humid this afternoon; warmer and more
  humid Sunday with isolated afternoon thunderstorms.

- 2) Late summer heat returns next week.

- 3) Thunderstorm chances increase next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Cooler and less humid this afternoon; warmer
and more humid Sunday with isolated afternoon thunderstorms.

High pressure will pass north of the area this afternoon and
then off the Mid Atlantic coast Sunday. It will be slightly
cooler and less humid this afternoon on NNW winds. As a result,
most areas should remain dry and seasonable this afternoon,
although an inverted surface trough may result in isolated
showers along the Allegheny Mountains. Southerly flow returns
Sunday, bringing increasing heat and humidity. A passing
shortwave trough may support a few afternoon showers and
thunderstorms about anywhere.

KEY MESSAGE 2...Late summer heat returns next week.

Guidance remains steadfast on late summer heat returning to end
meteorological summer (June 1-August 31) and begin meteorological
autumn (September 1-November 30).

A strong mid-level ridge will build across the southern CONUS and
into the Mid-Atlantic beginning on Sunday, and persist through at
least the middle of the week. Some guidance has been trending
towards having the ridge axis a bit further south and west, which
would lower heights a bit and introduce more chances for showers and
thunderstorms at times in large scale NW flow aloft. This lends to a
bit of spread in the temperature forecast, especially if any back-
door surface cold fronts slide into the region by mid/late week.

Despite the uncertainties, it remains likely that high temperatures
will reach the lower to middle 90s for much of the region for much
of the upcoming week. Depending on smaller scale details, dew points
could end up a little higher or lower than currently progged which
will ultimately affect how high heat index values get. Values
approaching Heat Advisory criteria (100-104 west of the Blue Ridge,
105-109 east of the Blue Ridge) can`t be ruled out, but the more
likely scenario is for heat indices a bit below those values.

KEY MESSAGE 3...Thunderstorm chances increase next week.

Disturbances rounding a ridge to the south and west in NW flow aloft
will introduce shower and thunderstorm chances at times next week.
The timing and amplitude of these waves have very low predictability
beyond a couple days in advance (at best). But the general theme
will be enhanced lift and shear clashing with an increasingly hot
and unstable airmass over or near the Mid-Atlantic. AI/ML guidance
has broad elevated probabilities of severe weather much of next
week, the details (including timing and magnitude/potential impact)
of which will be ironed out in the coming days.

It should be noted that there is a conditional potential for one or
more organized clusters of strong to severe storms at some point
next week. The most likely time currently appears to be around mid
week, but changes are to be expected at this time range.

&&

.AVIATION /14Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions this afternoon through Monday. Isolated t-storms
possible Sunday afternoon.

Prevailing VFR expected through early next week, with PM TS and
early AM valley fog possibly introducing restrictions at times.
Winds will generally be S/SW (except briefly NW Mon) 5-10 kts.

&&

.MARINE...
SCA conditions possible again Sunday night into Monday morning
in southerly channeling.

Some southerly channeling could result in at or near SCA criteria
gusts Sunday evening into early Monday morning. Additional bouts of
channeling may be possible by mid next week.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

DISCUSSION...LFR/KLW/DHOF
AVIATION...LFR/KLW/DHOF
MARINE...LFR/KLW/DHOF