Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

950
FXUS61 KLWX 142356
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
756 PM EDT Tue Jul 14 2026

.WHAT HAS CHANGED...
No changes to the current forecast package. Heat Advisories have
been issued for most locations east of the Alleghenies Wednesday
with additional heat headlines needed for portions of the area
Thursday.

&&

.KEY MESSAGES...
- 1) Heat Advisories have been issued for most of the area Wednesday
as records are challenged. Heat continues through Friday.

- 2)Thunderstorm chances increase this weekend and could potentially
linger into early next week as a front drops into the region.

&&

.DISCUSSION...
KEY MESSAGE 1...Heat Advisories have been issued for most of the
area Wednesday as records are challenged. Heat continues through
Friday.

Not too much of a change in the forecast with hazardous heat,
humidity, and poor air quality expected for the midweek period. Heat
Advisories have been issued for most of the area Wednesday outside
of the mountains and southern Shenandoah Valley. These locations
will be just shy of criteria given lower dewpoint/humidity values.
Even with that said, expect heat indices between 96-102 degrees
outside of the advisory with 100-105 degree heat indices in the
advisory area (i.e the Baltimore/DC metros). Air temperatures
will near record levels (see climate section below) with most
seeing highs east of the Alleghenies in the upper 90s and lower
100s. A strong dome of high pressure of central Great Lakes is
to thank for the high heat yielding a steady supply of +25 to
+28 degree C 850 mb warm air advection into the region. Similar
temperatures and heat indices are expected on Thursday although
a few more clouds and an isolated thunderstorm may be observed
since the atmosphere will be less capped. Heat headlines will
likely be needed once again for portions of the region Thursday
midday through Thursday evening.

On top of the heat, will come the concern for haze/poor air quality.
The respective air quality agencies in MD and VA have issued Code
Orange Air Quality Alerts for the DC/Baltimore metros. This is
largely due in part to dense smoke aloft from wildfires over western
Ontario, Canada. Over the next couple of days, the smoke may
circulate across the area around the periphery of the upper high
over the Midwest. So, expect gradually deteriorating air quality
conditions across the local area through Friday..


KEY MESSAGE 2...Thunderstorm chances increase this weekend and could potentially
linger into early next week as a front drops into the region.


Temperatures are expected to run a few degrees cooler but remain
hot on Friday with forecast highs in the 90s. Dewpoints are forecast
to drop into the 50s behind a weak frontal boundary that will move
through from the northeast, leading to lesser instability and
decreased chances for afternoon showers and thunderstorms locally.

A shortwave disturbance will descend down in northwesterly flow
through the Great Lakes on Saturday. Surface winds will turn out of
the southwest in response to the approaching shortwave, drawing
deeper moisture back northward into our forecast area. Most
solutions favor dewpoints reaching near 70 during the afternoon
hours. That coupled with height falls aloft ahead of the shortwave
will lead to increased chances for afternoon showers and
thunderstorms. Some of these storms could potentially turn strong to
severe with modest flow aloft and a high CAPE/DCAPE thermodynamic
environment in place. Forecast confidence decreases by Sunday, but
thunderstorms could be possible again if the system`s cold front
remains upstream, keeping a more unstable airmass in place.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions will likely continue through Thursday night under
mostly dry conditions. One thing of note will be smoke aloft from
fires burning over western Ontario. This will result in a hazy
appearance of the sky through Friday although vsby reductions are
not expected at this time. An isolated thunderstorm is possible
Thursday afternoon and evening although confidence remains low at
this time.

Prevailing VFR conditions are expected Friday into the upcoming
weekend. Showers and thunderstorms will be possible each
afternoon and evening with the greatest opportunity for
restrictions this weekend. Winds will remain light out of the
west and northwest with speeds less than 15 kts.

&&

.MARINE...
Southerly channeling will likely result in a period of SCA
conditions tonight across the middle and lower Bay.

Sub-SCA level northwesterly winds are expected Thursday and Friday.
SMWs may potentially be needed on Thursday or Friday if
thunderstorms move over the waters. More widespread thunderstorm
activity and the need for SMWS will be needed over the weekend as a
cold front sags into the region. Southerly channeling also returns
to portions of the waters Saturday into Sunday.

&&

.CLIMATE...
A period of well above normal temperatures is expected Wednesday
and Thursday, with daily record highs likely to be set for some
locations on Wednesday, although Thursday looks hotter.

Below is a list of record daily high and warm low temperatures for
July 15 (Wednesday) and July 16 (Thursday).

=================================================================
         July 15 Record Daily High/Warm Low Temperatures
=================================================================
Baltimore MD                 102 (2024, 1995)   79 (1995, 1936)
Washington DC                102 (2024)         81 (2024)
Sterling-Dulles Airport VA    99 (2024)         75 (2024)
Baltimore (Downtown) MD      101 (2024)         85 (1988)
Annapolis MD                 101 (1995)         81 (1896)
Hagerstown MD                102 (1954)         78 (2024)
Martinsburg WV               107 (1936)         75 (1995)
Charlottesville VA           102 (1954)         76 (1936)

=================================================================
         July 16 Record Daily High/Warm Low Temperatures
=================================================================
Baltimore MD                 104 (2024, 1988)   78 (1879)
Washington DC                104 (2024, 1988)   84 (1983)
Sterling-Dulles Airport VA   104 (1988)         74 (2013)
Baltimore (Downtown) MD      105 (2024)         85 (2013)
Annapolis MD                  98 (1997, 1900)   79 (2024, 2013, 1955)
Hagerstown MD                104 (1988)         76 (2024)
Martinsburg WV               107 (1988)         77 (1983)
Charlottesville VA           102 (1988)         82 (1983)

Period of Record (POR) information (records since):
Baltimore MD - July 1872
Washington DC - January 1872
Sterling - Dulles Airport VA - January 1960
Baltimore (Downtown) MD - July 1950
Annapolis MD - January 1894
Hagerstown MD - January 1899
Martinsburg WV - January 1891
Charlottesville VA - January 1893

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Heat Advisory from 11 AM to 8 PM EDT Wednesday for DCZ001.
MD...Heat Advisory from 11 AM to 8 PM EDT Wednesday for MDZ003>006-
     008-011-013-014-016>018-502>508.
VA...Heat Advisory from 11 AM to 8 PM EDT Wednesday for VAZ026>031-
     040-051-053>057-501-502-505-506-526-527.
WV...Heat Advisory from 11 AM to 8 PM EDT Wednesday for WVZ050>053-
     055-502-504.
MARINE...Heat Advisory from 11 AM to 8 PM EDT Wednesday for ANZ530.
     Small Craft Advisory until 7 AM EDT Wednesday for ANZ532>534-
     541>543.

&&

$$

DISCUSSION...LFR/KJP/EST/DHOF
AVIATION...LFR/KJP/EST
MARINE...LFR/KJP/EST