735
FXUS61 KLWX 020816
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
416 AM EDT Thu Jul 2 2026
.WHAT HAS CHANGED...
Shenandoah, Frederick, Page, Warren, Clarke, Hampshire, Hardy,
Eastern Grant, Eastern Mineral, and Nelson Counties were
upgraded from a Heat Advisory to an Extreme Heat Warning for
today. Those counties are now under Extreme Heat Warnings both
today and tomorrow.
&&
.KEY MESSAGES...
- (1) Extreme heat and humidity builds over the region through the
Independence Day holiday weekend.
- (2) Thunderstorm chances increase through this weekend, with
an increased risk for severe thunderstorms Friday into the
Independence Day weekend.
3) Additional showers & thunderstorms are possible early next
week along with a marginal decrease in heat.
&&
.DISCUSSION...
KEY MESSAGE 1...Extreme heat builds over the region through the
Independence Day holiday weekend.
The ongoing heat wave will continue as a strong upper level
ridge/closed anticyclone continues to build overhead through
Friday. The peak of the heat and humidity is forecast to move
into the area for today and tomorrow, when when model guidance
shows 850 hPa temperatures soaring to around 24-25 C. This
should yield high temperatures between 100 and 105 at lower
elevations, which when combined with dewpoints in the upper 60s
and lower 70s will result in peak heat indices around 105-110 to
the west of the Blue Ridge, and 110-115 further east. Extreme
Heat Warnings and Heat Advisories remain in effect across the
majority of the forecast area for both today and tomorrow. Daily
record high temperatures may be challenged at several
locations over the next few days. See the climate section at
the bottom of the forecast discussion for more details.
It looks as though the heat and humidity will likely hold on
through the weekend as well. However, confidence in the high
temperature forecast starts to decrease a bit, as both remnant
cloud debris from previous days and new thunderstorm development
could potentially have an impact on temperatures. Because of
these uncertainties, no additional heat headlines were issued
for this weekend. It`s likely that at least some heat headlines
will eventually be needed once confidence in the temperature
forecast increases further. As of now, the current forecast
calls for high temperatures in the upper 90s/lower 100s at lower
elevations on Saturday (Independence Day), and mid- upper 90s
on Sunday.
Overnight low temperatures each night will be in the 70s for
most, with lower 80s in the urban centers. As a result, there
will be very little relief from the heat overnight.
KEY MESSAGE 2...Thunderstorm chances increase through this
weekend, with an increased risk for severe thunderstorms Friday
through Independence Day weekend.
Model soundings show strong capping today as the upper ridge
continues to build in from the west. As a result, no thunderstorm
activity is expected.
Things begin to change starting tomorrow into Saturday as
shortwave disturbances pass by to our north through the Great
Lakes, leading to persistent mid-level height falls and
continued weakening of the ridge. Model soundings still show
some capping present tomorrow, but the ridge may weaken just
enough to get a few thunderstorms to form during the afternoon
and evening hours. Coverage of storms should be low, with 00z
CAMs favoring development of thunderstorms the most in the
Central Shenandoah Valley to Central Virginia. However, a stray
storm can`t be ruled out anywhere. Shear will be lacking, but
pulse storms that produce strong downbursts will be possible,
given the very high CAPE/DCAPE, steep low-level lapse rate
environment in place. SPC currently has the majority of the
forecast area outlooked in a Marginal Risk for severe
thunderstorms tomorrow.
Coverage of thunderstorms should be higher on
Saturday/Independence Day with lesser capping present and
greater large scale forcing for ascent as height falls continue
aloft. The thermodynamic environment on Saturday will be
similar to Friday, with temperatures near 100, dewpoints around
70, MLCAPE around 3000 J/kg, and DCAPE values well over 1000
J/kg. However, winds in the 700-500 hPa layer will start to
increase to near 30 knots, which when combined with the lesser
capping and stronger large scale forcing for ascent may lead to
both higher coverage, and greater organization of storms
compared to Friday. Very strong downbursts and damaging winds
will be possible with any thunderstorms on Saturday. SPC
currently has the majority of the forecast area outlooked in a
Slight Risk for severe thunderstorms.
KEY MESSAGE 3...Additional showers & thunderstorms are possible early
next week along with a marginal decrease in heat.
As the upper-level ridge continues to buckle, a trough over the
Great Lakes will form with a stemming cold front tracking through
the region by early next week. This could cause additional chances
for showers and thunderstorms through potentially Monday and
Tuesday, although the speed at which this weekend`s trough tracks
south will be critical for these continued chances to materialize.
Although ML models currently show Saturday & Sunday afternoon/evening
as the strongest contenders for severe thunderstorms, there is a
15%- 30% probability outlined for Monday in NCAR`s AI NWP Convective
Hazards Forecast. Synoptic setup in the days beforehand will be
critical in understanding the nature & scope of thunderstorms
during this period.
Temperatures look to potentially drop as this cold front tracks
to the south by early Tuesday, although dewpoints will remain
elevated for now resulting in continued humid conditions.
Nevertheless, heat indices look to potentially dip back into
double digits by Tuesday afternoon in the metros.
&&
.AVIATION /07Z THURSDAY THROUGH MONDAY/...
Prevailing VFR conditions are expected at the terminals over the
next several days. The main concern will be thunderstorms. No
thunderstorm activity is expected today. A few thunderstorms may
be possible late tomorrow afternoon into tomorrow evening, with
CHO having the highest chance at seeing a storm. More widespread
thunderstorm activity is expected on Saturday, Sunday, and
Monday. Some of the storms could potentially turn strong to
severe. Outside of storms, winds will largely be light and
variable over the next several days. The exception could be MTN
this afternoon into this evening, where southerly winds
channeling up the Bay could gust to around 15-20 knots.
&&
.MARINE...
SCAs are in effect in for the Bay and Lower Tidal Potomac within
southerly channeling late this afternoon through this evening.
Other than that, background sub-SCA level winds are forecast
through Saturday. Wind direction will vary by location over the
next several days, with Bay locations maintaining more of a
southerly component of the wind, while the middle and upper
Tidal Potomac more frequently experience west to southwesterly
winds. No thunderstorms are expected today, but chances for
afternoon and evening thunderstorms increase Friday afternoon,
and especially moving into the upcoming weekend. Some of these
storms may potentially be on the stronger side, with SMWs likely
at times.
Winds stay below SCA thresholds Sunday & Monday. Showers &
thunderstorms are possible in the afternoon & evening hours through
early next week.
&&
.TIDES/COASTAL FLOODING...
Annapolis, and potentially Baltimore may reach Action Stage with
the tide cycle this morning. Anomalies are on the decrease
however, and water levels are forecast to stay below Action
Stage for subsequent tide cycles.
&&
.CLIMATE...
There is a significant heat risk this week. The numbers below
aren`t a forecast, but rather a reference for historical context
for comparison. Latest forecast: weather.gov/lwx. Note that
Dulles did break a record today with the high temperature of 97
degrees (July 1, 2026).
==================================================================
*** ALL-TIME RECORD HIGHS ***
==================================================================
Baltimore 107 (set on Jul 10, 1936)
Washington 106 (set on Jul 20, 1930 + Aug 06, 1918)
Sterling-Dulles Airport 105 (set on Jul 22, 2011)
Baltimore Downtown 108 (set on Jul 07, 2012 + Jul 22, 2011)
Annapolis 106 (set on Aug 06, 1918)
Hagerstown 105 (set on Jul 14, 1954)
Martinsburg 112 (set on Jul 11, 1936)
Charlottesville 107 (set on Sep 07, 1954 + 3 other times)
==================================================================
*** ALL-TIME RECORD WARM LOWS ***
==================================================================
Baltimore 83 (set on Aug 05, 1930 + 2 other times)
Washington 84 (set on Jul 24, 2011 + 2 other times)
Sterling-Dulles Airport 79 (set on Aug 08, 2007)
Baltimore Downtown 88 (set on Jul 22, 2011 and Jul 10, 1993)
Annapolis 92 (set on Jul 07, 1994)
Hagerstown 86 (set on Jun 15, 1899)
Martinsburg 86 (set on Jul 21, 1930)
Charlottesville 85 (set on Aug 07, 1918)
==================================================================
*** JULY MONTHLY RECORD HIGHS ***
==================================================================
Baltimore 107 (set on Jul 10, 1936)
Washington 106 (set on Jul 20, 1930)
Sterling-Dulles Airport 105 (set on Jul 22, 2011)
Baltimore Downtown 108 (set on Jul 07, 2012 + Jul 22, 2011)
Annapolis 105 (set on Jul 21, 1930 + Jul 02, 1901)
Hagerstown 105 (set on Jul 14, 1954)
Martinsburg 112 (set on Jul 11, 1936)
Charlottesville 107 (set on Jul 10, 1936 + Jul 20, 1930)
==================================================================
*** JULY MONTHLY RECORD WARM LOWS ***
==================================================================
Baltimore 83 (set on Jul 21, 1930)
Washington 84 (set on Jul 24, 2011 + 2 other times)
Sterling-Dulles Airport 78 (set on Jul 24, 2010 + Jul 08, 2010)
Baltimore Downtown 88 (set on Jul 22, 2011 + Jul 10, 1993)
Annapolis 92 (set on Jul 07, 1994)
Hagerstown 83 (set on Jul 24, 2010)
Martinsburg 86 (set on Jul 21, 1930)
Charlottesville 84 (set on Jul 22, 1930)
==================================================================
*** DAILY RECORD HIGHS | WARM LOWS ***
VALID: Jul 02
==================================================================
Baltimore 103 (1901) | 80 (1901)
Washington 101 (1898) | 79 (2012 + 1872)
Sterling-Dulles Airport 98 (1966) | 75 (2022)
Baltimore Downtown 102 (1966) | 84 (2002)
Annapolis 105 (1901) | 80 (1901)
Hagerstown 100 (1966) | 74 (2018 + 1901)
Martinsburg 102 (1933 + 1931) | 75 (1933 + 1901)
Charlottesville 100 (1954) | 76 (1910)
==================================================================
*** DAILY RECORD HIGHS | WARM LOWS ***
VALID: Jul 03
==================================================================
Baltimore 104 (1898) | 80 (1898)
Washington 101 (1966 + 2) | 80 (2018)
Sterling-Dulles Airport 103 (1966) | 73 (2018 + 2)
Baltimore Downtown 102 (1997) | 82 (2018 + 1983)
Annapolis 100 (1901) | 84 (1896)
Hagerstown 102 (1966) | 76 (2002)
Martinsburg 102 (1941 + 1911) | 74 (1980)
Charlottesville 100 (1966 + 1954) | 79 (1911)
==================================================================
*** DAILY RECORD HIGHS | WARM LOWS ***
VALID: Jul 04
==================================================================
Baltimore 100 (2002 + 2) | 78 (1911)
Washington 100 (1919) | 80 (2018 + 2002)
Sterling-Dulles Airport 97 (2002 + 1999) | 75 (2018)
Baltimore Downtown 101 (2002 + 1990) | 83 (2002)
Annapolis 98 (1999) | 81 (2018)
Hagerstown 100 (1966 + 1919) | 76 (2018)
Martinsburg 103 (1898) | 76 (1999)
Charlottesville 100 (2012) | 78 (1919)
-----------------------------------------------------------------
Number of Consecutive Days Max Temp >=100
Area (obs site) Records since
------------------------------------------------------------------
Baltimore (BWI) 4 days July 14-17,2024 & July 19-22,1930
Washington (DCA) 4 days July 14-17, 2024 & July 5-8, 2012
Sterling-Dulles (IAD) 2 days July 7-8, 2012, July 21-22, 2011
July 6-7, 2010, July 16-17, 1997
Baltimore Downtown (DMH) 5 days July 3-7, 2010 & July 7-11, 1993
Annapolis (NAK) 1 day July 21, 2019, July 7, 2012,
July 22, 2011, June 29, 1959
Hagerstown (HGR) 3 days July 5-7, 2010
Martinsburg (MRB) 6 days June 1-6, 1925
Charlottesville (CHO) 5 days July 4-8, 2012
Period of Record (POR) context...
Area (obs site) Records since
------------------------------------------------------------------
Baltimore (BWI) Jan 1872
Washington (DCA) Jul 1872
Sterling-Dulles Airport (IAD) Jan 1960
Baltimore Downtown (DMH) Jul 1950
Annapolis (NAK) Jan 1894
Hagerstown (HGR) Jan 1899
Martinsburg (MRB) Jan 1891
Charlottesville (CHO) Jan 1893
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Extreme Heat Warning from 10 AM this morning to 8 PM EDT this
evening for DCZ001.
Extreme Heat Warning from 10 AM to 8 PM EDT Friday for DCZ001.
MD...Extreme Heat Warning from 10 AM this morning to 8 PM EDT this
evening for MDZ003>006-008-011-013-014-016>018-502>508.
Extreme Heat Warning from 10 AM to 8 PM EDT Friday for
MDZ003>006-008-011-013-014-016>018-502>508.
Small Craft Advisory from 4 PM this afternoon to 2 AM EDT
Friday for MDZ008.
Heat Advisory from 10 AM this morning to 8 PM EDT this evening
for MDZ501.
Heat Advisory from 10 AM to 8 PM EDT Friday for MDZ501.
VA...Extreme Heat Warning from 10 AM this morning to 8 PM EDT this
evening for VAZ027>031-036>040-050-051-053>057-501-502-
505-506-526-527.
Extreme Heat Warning from 10 AM to 8 PM EDT Friday for
VAZ027>031-036>040-050-051-053>057-501-502-505-506-526-
527.
Heat Advisory from 10 AM this morning to 8 PM EDT this evening
for VAZ025-026-504.
Heat Advisory from 10 AM to 8 PM EDT Friday for VAZ025-026-504.
WV...Extreme Heat Warning from 10 AM this morning to 8 PM EDT this
evening for WVZ050>053-055-502-504.
Extreme Heat Warning from 10 AM to 8 PM EDT Friday for
WVZ050>053-055-502-504.
Heat Advisory from 10 AM this morning to 8 PM EDT this evening
for WVZ503-506.
Heat Advisory from 10 AM to 8 PM EDT Friday for WVZ503-506.
MARINE...Extreme Heat Warning from 10 AM this morning to 8 PM EDT this
evening for ANZ530.
Extreme Heat Warning from 10 AM to 8 PM EDT Friday for ANZ530.
Small Craft Advisory from 4 PM this afternoon to 2 AM EDT
Friday for ANZ530>534-537>543.
&&
$$
DISCUSSION...KJP/SRT
AVIATION...KJP/SRT
MARINE...KJP/SRT
NWS LWX Office Area Forecast Discussion