832
FXUS61 KLWX 230049
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
849 PM EDT Sun Jun 22 2025
.SYNOPSIS...
A prolonged period of very hot weather is expected through the
middle of the week as a large ridge of high pressure builds
over the eastern United States. A risk of showers and
thunderstorms returns during the middle to latter portions of
the week as a frontal system approaches from the north. This
system stalls nearby late in the week.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Earlier showers and storms that moved in from the northeast have
since decayed. A few remnant cirrus clouds are slowly drifting
off toward the south of DC, with clear skies further north.
Once those high clouds clear the area over the next couple
hours, clear skies are expected through the remainder of the
night. Temperatures will remain very warm overnight, with lows
in the 70s for most. Temperatures may hold near or just above 80
degrees in downtown DC and Baltimore. Some river valley fog may
also be possible closer to daybreak, especially to the west of
the Blue Ridge.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY NIGHT/...
The heat will peak Monday and Tuesday (with little change into
Wednesday) as the mid and upper ridge builds overhead. There is
still some uncertainty with the interplay of temperatures and
dew points due to the northwesterly winds which could promote
drier air mixing to the surface. However, not to get bogged down
in product criteria, it will simply be hot with heat index
values of 100-110 each day in the lower elevations (potentially
a little higher in spots). Heat Advisories and Extreme Heat
Warnings are in effect, with a Watch hoisted for Tuesday due to
some uncertainty in the location of the hottest conditions.
Even in the higher elevations, heat index values will be in the
upper 80s to lower 90s. Little relief will come at night with
temperatures generally in the 70s to lower 80s. The ridge should
put a cap on convection. However, there could be a slightly
better chance of a rogue pop-up Tuesday as the ridge starts to
drift back to the southwest.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Ridging will hold firm to the south and west of the region during
the second half of the week and into next weekend, but will begin to
erode or weaken a bit. With the Mid-Atlantic on the periphery of the
gradually flattening ridge, large scale subsidence will abate a bit.
This opens the door to daily afternoon/evening shower/thunderstorm
chances. Ample instability will be present given high heat and
humidity, with daily temperatures well into the 90s and heat index
values making a run at the century mark. There will be very little
flow to organize storms, though individual cells could become rather
potent over localized areas. Will have to monitor for any small
scale perturbations in the large scale pattern that could cause an
uptick in convective prowess later in the week. High humidity and
slow-moving storms raises some questions regarding heavy rainfall,
as well.
The extended stretch of hot and humid conditions with very warm
overnight temperatures greatly increases the risk of heat illness.
Therefore, it is imperative to have a plan to stay cool during this
upcoming prolonged period of heat.
&&
.AVIATION /01Z MONDAY THROUGH FRIDAY/...
VFR conditions are likely through Tuesday. Light winds will
generally be out of the west to northwest except near the
influence of the Potomac and Chesapeake (DCA/BWI/MTN).
VFR will prevail Wed/Thu, though brief sub-VFR is possible in any
pop up PM TS. Winds look light NW Wed, then S/SW Thu.
&&
.MARINE...
Diurnal wind direction fluctuations are expected through
Tuesday due to weak pressure gradients associated with large
high pressure. Winds should generally be 10 kt or less. There is
some potential for brief southerly channeling on the wider
waters this evening, but the threat seems localized enough that
it can likely be handled with a statement if a few gusts to 20
kt start to occur. Dry conditions are likely Monday and
Tuesday.
A prolonged period of heat will persist through the end of the
upcoming week. Be mindful that although winds will remain light
overall, isolated strong afternoon and evening thunderstorms may pop
up, and bring an attendant threat of gusty winds and lightning.
&&
.TIDES/COASTAL FLOODING...
Southerly flow has resulted in slightly higher tidal anomalies
(around 0.6 ft). This will generally result in some caution
stages at some locations, although Annapolis will be close to
minor flood stage this evening. Northwest winds should help
anomalies drop a bit by Monday.
&&
.CLIMATE...
Here are some daily high temperature records during the June 22-27
timeframe:
A `+` sign indicates multiple years currently hold that record.
***SUNDAY, JUNE 22ND, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 101F (1988) 78F (2015)
Washington-Dulles (IAD) 100F (2024) 75F (2024)
Baltimore (BWI) 101F (2024) 77F (1933)
Baltimore Inner Harbor (DMH) 104F (1988) 84F (1988)
Martinsburg (MRB) 102F (1933) 71F (1934)
Charlottesville (CHO) 101F (1933) 76F (1933)
Annapolis (NAK) 101F (1988) 81F (1896)
Hagerstown (HGR) 100F (1988) 76F (2024)
***MONDAY, JUNE 23RD, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 99F (2024) 81F (2024)
Washington-Dulles (IAD) 98F (2024) 78F (2024)
Baltimore (BWI) 98F (2024) 81F (2024)
Baltimore Inner Harbor (DMH) 99F (2024)+ 83F (2024)
Martinsburg (MRB) 100F (1934) 72F (2024)+
Charlottesville (CHO) 100F (1894) 76F (1996)
Annapolis (NAK) 98F (1988) 77F (2011)
Hagerstown (HGR) 98F (2010) 78F (2024)
***TUESDAY, JUNE 24TH, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 100F (2010) 78F (2010)
Washington-Dulles (IAD) 97F (2010) 73F (2010)
Baltimore (BWI) 100F (2010) 76F (2010)+
Baltimore Inner Harbor (DMH) 101F (2010)+ 82F (2010)
Martinsburg (MRB) 97F (1943) 70F (2024)+
Charlottesville (CHO) 101F (1930) 74F (1914)
Annapolis (NAK) 97F (2000)+ 81F (1896)
Hagerstown (HGR) 96F (2010)+ 75F (2010)
***WEDNESDAY, JUNE 25TH, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 100F (1977) 76F (2010)+
Washington-Dulles (IAD) 97F (1966) 71F (1981)
Baltimore (BWI) 99F (1997) 77F (1949)+
Baltimore Inner Harbor (DMH) 104F (1997) 79F (1998)+
Martinsburg (MRB) 99F (1997) 72F (1949)
Charlottesville (CHO) 99F (1997) 77F (1951)
Annapolis (NAK) 98F (2000)+ 78F (1997)+
Hagerstown (HGR) 98F (1952) 75F (1949)
***THURSDAY, JUNE 26TH, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 101F (1952) 77F (1952)+
Washington-Dulles (IAD) 99F (2024) 72F (2023)+
Baltimore (BWI) 99F (2024)+ 80F (1952)
Baltimore Inner Harbor (DMH) 104F (1998) 83F (1952)
Martinsburg (MRB) 102F (1943) 75F (1949)
Charlottesville (CHO) 99F (1998) 78F (1952)
Annapolis (NAK) 98F (1998)+ 81F (1952)
Hagerstown (HGR) 98F (1954)+ 75F (1952)
***FRIDAY, JUNE 27TH, 2025***
LOCATION RECORD HIGH (YEAR) RECORD WARM LOW (YEAR)
Washington-National (DCA) 99F (2010) 80F (1952)
Washington-Dulles (IAD) 100F (1964) 72F (2021)+
Baltimore (BWI) 100F (2010) 78F (1949)+
Baltimore Inner Harbor (DMH) 101F (2010) 83F (1998)
Martinsburg (MRB) 101F (1943) 75F (1952)
Charlottesville (CHO) 100F (1952) 79F (1952)
Annapolis (NAK) 98F (1911) 79F (1943)
Hagerstown (HGR) 99F (2010) 77F (1952)
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Extreme Heat Warning from 11 AM to 9 PM EDT Monday for DCZ001.
Extreme Heat Watch from Tuesday morning through Tuesday
evening for DCZ001.
MD...Extreme Heat Warning from 11 AM to 9 PM EDT Monday for
MDZ003>006-008-011-013-014-016>018-503>508.
Extreme Heat Watch from Tuesday morning through Tuesday
evening for MDZ003>006-008-011-013-014-016>018-503>508.
Heat Advisory from 11 AM to 9 PM EDT Monday for MDZ502.
Heat Advisory from 11 AM to 9 PM EDT Tuesday for MDZ502.
VA...Extreme Heat Warning from 11 AM to 9 PM EDT Monday for
VAZ027>031-053>057-502-505-506-526-527.
Extreme Heat Watch from Tuesday morning through Tuesday
evening for VAZ027>031-036>040-050-051-053>057-501-502-
505-506-526-527.
Heat Advisory from 11 AM to 9 PM EDT Monday for VAZ025-026-
036>040-050-051-501.
Heat Advisory from 11 AM to 9 PM EDT Tuesday for VAZ025-026.
WV...Extreme Heat Warning from 11 AM to 9 PM EDT Monday for WVZ052-
053.
Extreme Heat Watch from Tuesday morning through Tuesday
evening for WVZ052-053.
Heat Advisory from 11 AM to 9 PM EDT Monday for WVZ050-051-055-
502-504-506.
Heat Advisory from 11 AM to 9 PM EDT Tuesday for WVZ050-051-
055-502-504-506.
MARINE...Extreme Heat Warning from 11 AM to 9 PM EDT Monday for ANZ530.
Extreme Heat Watch from Tuesday morning through Tuesday
evening for ANZ530.
&&
$$
SYNOPSIS...BRO
NEAR TERM...KJP
SHORT TERM...ADS
LONG TERM...DHOF
AVIATION...ADS/DHOF
MARINE...ADS/DHOF
TIDES/COASTAL FLOODING...ADS
CLIMATE...BRO