Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

029
FXUS61 KLWX 150607
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
207 AM EDT Wed Jul 15 2026

.WHAT HAS CHANGED...
Aside from blending in better performing temperature/dew point
guidance for today, no changes to forecast.

&&

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

No changes to the forecast for today or Thu with a continental
ridge of high pressure flexing over the area. Difference for
this heat spell is the source region is continental in nature.
This will result in potentially higher MaxTs, but also less
humid with more of a w`ly sfc component rather a s`ly component.

Heat Advisories have been issued for most of the area today outside
of the mountains and southern Shenandoah Valley. These
locations will be just shy of criteria given lower
Td 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
temps 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 temps and heat indices are expected on Thu although a
few more clouds and an isolated t-storm may be observed since
the atmosphere will be less capped. Heat headlines will likely
be needed once again for portions of the region Thu.

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 Fri.

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

Temps are expected to run a few degrees cooler but remain hot
on Fri with highs in the 90s. Tds are forecast to drop into the
50s behind a weak front that will move through from the NE,
leading to lesser instability and decreased chances for
afternoon showers and t-storms.

A sw disturbance will descend down in NW`ly flow through the
Great Lakes on Sat. Surface winds will turn out of the
SW in response to the approaching sw, drawing deeper moisture
back nwrd into our FA. Most solutions favor Tds reaching near 70
during the afternoon hours. That coupled with height falls
aloft ahead of the sw will lead to increased chances for
afternoon showers and t-storms. Some of these storms could
potentially be strong to severe with modest flow aloft and a
high CAPE/DCAPE environment in place. Forecast confidence
decreases by Sun, but t-storms could be possible again if the
system`s cold front remains upstream, keeping a more unstable
airmass in place.

&&

.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
VFR & mostly dry conditions will likely continue through Thu.
Smoke aloft will result in a hazy appearance of the sky through
Fri although vsby reductions are not likely at this time. An
isolated t-storm is possible Thu afternoon/evening although
confidence remains low at this time.

Prevailing VFR conditions are expected Fri into the weekend.
Showers and t-storm will be possible each afternoon/evening
with the greatest likelihood this weekend. Winds will remain
light out of the W and NW with speeds less than 15 kts.

&&

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

Sub-SCA level NW`ly winds are expected Thu and Fri. More
widespread t-storm activity and the need for SMWS will be
needed over the weekend as a cold front sags south. S`ly
channeling also returns to portions of the waters Sat into Sun.

&&

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

&&

$$

DISCUSSION...CPB/EST
AVIATION...CPB/EST
MARINE...CPB/EST