Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

053
FXUS61 KLWX 311352
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
952 AM EDT Mon Aug 31 2026

.WHAT HAS CHANGED...
Updated rain/thunderstorm chances for today to account for more
isolated nature of storms today. Also, incoming cloud cover may
limit max temps this afternoon.

&&

.KEY MESSAGES...
- 1) Scattered thunderstorms expected again today.

- 2) Near-record early September heat expected.

- 3) Thunderstorm chances increase this week, but timing remains highly
     uncertain.

&&

.DISCUSSION...
KEY MESSAGE 1...Scattered thunderstorms possible this afternoon.

Spotty showers continue over the Alleghenies and north/northeast
MD this morning. The expansive cloud cover could end up keeping
highs this afternoon lower than forecast. Will take a closer
look at this once the 12Z models begin coming in over the next
few hours. South of I-66 is likely where temps rise to the low
90s as clouds don`t arrive there until much later in the day.

The highest chances for thunderstorms may end up being down in
central VA where higher instability is more likely due to
sunnier skies. Still, could end up seeing a few pockets of
thunderstorms develop along I-81 this afternoon, pushing east of
the Blue Ridge early this evening. Most of the thunderstorms
dissipate after sunset, though some showers likely linger along
and east of I-95 into the late evening. Dry and mostly cloudy
tonight as lows settle in the 70s.

KEY MESSAGE 2...Near-record early September heat expected.

A strong mid-level ridge over the southern Plains will build toward
the Mid South during the early to middle part of the week. The
latest trend is for the ridge to build further east into the TN
Valley on Tuesday and Wednesday, then break down late in the week as
a strong trough digs down from southern Canada. Having the ridge
build to the east is going to keep hot and mostly dry conditions
over the region for longer.

Despite the uncertainties, it remains likely that high temperatures
will reach the lower to middle 90s for most of the area this week.
Latest guidance indicates potential for temperatures in the upper
90s to near 100 by mid week, so long as it is not disrupted by cloud
cover or convection. 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) are possible Tuesday through
Thursday. Similar heat and humidity could persist into Friday, but
there is a lot of uncertainty for the late week temperature forecast
due to possible convective systems moving through the area.

Temperatures may begin to moderate by next weekend as a cold front
crosses the region.

KEY MESSAGE 3...Thunderstorm chances increase this week, but
timing remains highly uncertain.

Disturbances rounding a ridge to the south and west in NW flow aloft
will introduce shower and thunderstorm chances at times this week.
Given the latest trend bringing the ridge further east during the
middle of the week, that should keep most of the convective systems
over NY/PA and the Northeast Tuesday and Wednesday. That does not
mean we are completely in the clear those days; if anything, the
highest chance of seeing thunderstorms will be in northeast Maryland
during the late afternoon to evening as storms move south from PA.
By Thursday, a strong upper trough digs south from Canada which will
rapidly break down the ridge overhead. As this occurs, our area is
going to be in a much more favorable location for upstream
shortwaves to pass overhead.

The enhanced lift and shear traversing the region besieged by
several days of hot and humid conditions will introduce the
potential for some significant severe weather. AI/ML guidance has
broad elevated probabilities of severe weather much of this week,
particularly Wednesday and Thursday. It should be noted that there
is a conditional potential for one or more organized clusters of
strong to severe storms at some point this week. The most likely
time currently appears to be either Wednesday or Thursday, but
changes are likely given uncertainty at this range. It is quite
possible given latest trends that the threat is highest Thursday and
Friday as the upper ridge breaks down more readily.

Storm chances may linger into next weekend as a cold front crosses
the region on Saturday.

&&

.AVIATION /13Z MONDAY THROUGH FRIDAY/...
Scattered thunderstorm development is expected this afternoon
and evening, mainly between 22Z-02Z. Some activity could linger
across eastern terminals, but should be mostly showers late this
evening. Given low confidence in exact location of thunderstorms
this afternoon, the PROB30 groups were maintained.

VFR this afternoon through Thursday for the most part. Timing,
coverage, and location will be the uncertainty each day and evening
for scattered strong to perhaps severe thunderstorms.
Any storms will bring brief MVFR to IFR conditions in terms of
downpours. Winds generally south to southwest 5 to 15 knots but very
gusty in strong thunderstorms. Can`t totally rule out some early AM
low clouds/fog either at times, but confidence is low.

&&

.MARINE...
Scattered thunderstorm development is expected this afternoon
and t-storms may be capable of producing strong wind gusts. SMWs
may be required.

Chances of thunderstorms increase throughout the week, so Special
Marine Warnings may be needed. Brief/marginal southerly channeling
can`t be ruled out each afternoon and evening.

&&

.CLIMATE...
Near-record heat is possible, peaking Tuesday through Thursday.

Below is a list of record warm temperatures for September 1, 2, and 3.

(A `+` indicates the record also occurred in previous years).

The period of record for most sites dates back to the late 1800s,
except for Sterling-Dulles Airport which dates back to 1960.

====================================================================
                            SEPTEMBER 1
====================================================================
Site                      Record Daily High   Record Daily Warm Low
Baltimore (BWI) MD           99 (1962)            78 (1932+)
Washington DC                99 (1980+)           77 (1980)
Sterling-Dulles Airport VA   98 (1980)            73 (2000)
Baltimore (Downtown) MD      99 (1973)            80 (2012)
Annapolis MD                 95 (1962)            78 (2018+)
Hagerstown MD               101 (1902)            72 (2018+)
Martinsburg WV              103 (1932)            73 (2000+)
Charlottesville VA          105 (1932)            78 (1932)

====================================================================
                            SEPTEMBER 2
====================================================================
Site                      Record Daily High   Record Daily Warm Low
Baltimore (BWI) MD           99 (1953)            75 (1932+)
Washington DC               101 (1980)            78 (1980)
Sterling-Dulles Airport VA   99 (1980)            72 (2020+)
Baltimore (Downtown) MD      98 (1980+)           80 (1980)
Annapolis MD                 97 (1998)            79 (2018+)
Hagerstown MD               100 (1953)            73 (2018+)
Martinsburg WV              103 (1932)            72 (2000+)
Charlottesville VA          105 (1953)            80 (1930)

====================================================================
                            SEPTEMBER 3
====================================================================
Site                      Record Daily High   Record Daily Warm Low
Baltimore (BWI) MD           98 (2023)            79 (1993)
Washington DC                98 (1953)            79 (1993)
Sterling-Dulles Airport VA   99 (2023)            77 (1993)
Baltimore (Downtown) MD      98 (2023)            82 (1993)
Annapolis MD                 99 (1993)            79 (2018)
Hagerstown MD               100 (1953)            72 (2018+)
Martinsburg WV              102 (1953)            71 (1957)
Charlottesville VA          104 (1953)            75 (1930)

&&

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

&&

$$

DISCUSSION...LFR/DHOF/KRR
AVIATION...LFR/DHOF
MARINE...LFR/DHOF