990
FXUS61 KLWX 010042
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
842 PM EDT Tue Mar 31 2026
.WHAT HAS CHANGED...
No significant changes were made to the forecast this evening.
&&
.KEY MESSAGES...
- 1) Near record temperatures through Wednesday ahead of an
approaching cold front that looks to bring showers and perhaps
a few strong to severe thunderstorms.
- 2) The front will waver near or just north of the area
Thursday through Saturday, resulting in warm conditions and
daily shower and thunderstorm chances.
- 3) A strong cold front passing through the region on Sunday
could bring widespread rainfall and a drop in temperatures by
early next week.
&&
.DISCUSSION...
.KEY MESSAGE 1...Near record temperatures through Wednesday ahead
of an approaching cold front that looks to bring showers and
perhaps a few strong to severe thunderstorms.
Conditions are dry this evening, with just some passing high clouds.
Temperatures remain mild, with south to southwesterly winds
holding temperatures in the 70s. Later tonight, some remnant
convection from the Great Lakes/Ohio Valley may drift into the
Allegheny Mountains and/or northern portions of the forecast
area. The greatest chance for measurable rain will be in Garrett
County. Otherwise, expect partly to mostly cloudy skies with
unseasonably warm temperatures in the upper 50s to mid 60s.
Higher thunderstorm coverage is expected Wednesday afternoon
and evening as a cold front drops into the region. There is some
question regarding thunderstorm coverage due to height rises
later in the day along with deep westerly (downsloping) flow.
However, steeper mid level lapse rates will result in tall CAPE
profiles with around 30 kt of shear. This could result in
multicell clusters capable of locally damaging winds and
perhaps some marginally severe hail. 12Z CAM guidance suggest
coverage/intensity may be slightly greater across the
Baltimore/Washington metro area. The convective threat should
diminish by late Wednesday evening, although some showers may
continue into the night as moisture overruns the front dropping
south into the area.
High temperatures on Wednesday will once again approach records.
While still mild, cooler air will start to filter in from the
northeast behind the front Wednesday night.
.KEY MESSAGE 2...The front will waver near or just north of the
area Thursday through Saturday, resulting in warm conditions
and daily shower and thunderstorm chances.
Most guidance continues to show the front stalling out directly
over the forecast area on Thursday between strong high pressure
cells over the western Atlantic and Quebec. This will lead to a
large contrast in temperatures from northeast to southwest
across the area, with continued uncertainty with how the
gradient will lie. To the northeast, temperatures will likely
remain in the 50s (with low clouds), while reaching the mid 80s
to the southwest. With strong upper ridging affecting the area,
precipitation chances will be limited. Some models suggest that
scattered showers and thunderstorms could form over the terrain
and/or near the front. At the moment, shear appears too weak to
support a severe weather threat.
The aforementioned front will lift northward Friday as low
pressure lifts northeastward from the Great Lakes. Temperatures
will moderate in return flow with widespread 70s to low 80s.
Precipitation chances Friday look to remain low with the main
forcing well to the north, but some convection could develop
near the terrain. Behind the low, the front may try to drop back
south toward the area, but likely halts as another low quickly
moves toward the Great Lakes Saturday. Thus Saturday may end up
pretty similar to Friday with well above normal temperatures and
the greatest chance for convection over the mountains.
.KEY MESSAGE 3...A strong cold front passing through the region
on Sunday could bring widespread rainfall and a drop in
temperatures by early next week.
The primary feature to note for this upcoming weekend is a
significant upper-level trough expected to form over the
Northern Plains region later this week and make its way eastward
towards the Great Lakes, from which a strong cold front would
track through the East Coast on Sunday. Widespread rainfall (a
few tenths of an inch) and a significant drop in temperatures
across the region could result from this. As far as thunderstorm
risk goes, ensemble instability still looks relatively low
overall; most early parameters currently show this predominantly
being a widespread rain event. The NCAR AI NWP Convective
Hazards Forecast does show the Midatlantic in its 15-30% severe
probability outlook, however, so it is something to still watch
for as the day gets closer. The GFS and ECMWF are relatively
aligned on timing and track of the center low as of the latest
model runs, but both models have seen significant changes in the
north/south track over the last couple days so that will be
something to watch for as well. Rain should move past the area
by Monday, with a notable cooldown expected in the wake of the
front.
&&
.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions are expected to continue through tonight. Breezy
conditions will remain with south to southwest winds. Winds at
2kft could top out around 40-45 kt for a time. As a result, LLWS
has been introduced to some of the TAFs.
Winds won`t be quite as gusty Wednesday, but could occasionally
gust to 20 kt. A cold front will drop toward the area late in
the day, resulting in increasing chances for showers and
thunderstorms. While coverage is still uncertain (thus PROB30
TAFs), there could be locally higher chances of stronger
thunderstorms for the Baltimore/Washington metro. This threat
should end by late evening, although a few showers may linger
into the night. Winds will shift to the northeast or east, and
IFR ceilings will likely move in north of the boundary. The
front will stall across the area Thursday, although ceilings may
gradually improve. CHO may remain south of the boundary and
never see the wind shift or lower ceilings. Any shower or
thunderstorm chance on Thursday would likely remain near MRB.
The front moves back northward Friday and Saturday with
southerly wind gusts to 20 kts possible. Convective chances each
day will likely be limited near or west of MRB.
A Sunday cold front will potentially bringing lower CIGs,
VSBYs, and a northwesterly wind shift. Widespread rainfall could
bring local impacts to terminals. Wind gusts will potentially
be somewhat elevated on Sunday in the wake of this frontal
boundary before gradually decreasing on Monday.
&&
.MARINE...
Gusty south to southwest flow will remain through tonight given
the gradient between high pressure offshore and a slow-moving
cold front approaching from the Great Lakes region. Winds may
drop subtly Wednesday, so will keep the Small Craft Advisory
expiration at noon. Shower and thunderstorm chances return to
the waters Wednesday afternoon and evening as a cold front drops
into the area. Special Marine Warnings may be needed for gusty
winds and hail.
Wind direction is a bit uncertain Wednesday night through
Thursday night the front will be stalled near the area. It`s
possible a push of northeasterly winds behind the front could
reach advisory criteria Wednesday night. At some point Thursday,
gusty southerly flow may take back over, especially for southern
waters.
The front will lift back north Friday and Saturday, with
advisories possible in the ensuing southerly flow. Thunderstorm
chances will likely remain well west of the waters both days. A
Sunday cold front will introduce a northwesterly wind shift.
SCA conditions are possible Sunday going into Monday morning in
the wake of this frontal boundary before gradually decreasing.
Gusty showers and thunderstorms are also possible.
&&
.CLIMATE...
Temperatures of 15 to 25 degrees above normal are expected
Tuesday and Wednesday. Below is a list of record daily high
temperatures for our regional climate sites.
=========================================================
Record Daily Highs and Warm Lows for March 31
Site High/Year(s) Set Warm Low/Year(s) Set
DCA 85/2025, 1981, 1979 63/1998
BWI 86/2025, 1998 68/1998
IAD 85/1998 62/1998
DMH 93/1998 73/1998
NAK 83/1979, 1945 61/1977
HGR 85/1998 57/1998
MRB 86/1998 62/1998
CHO 88/1986 67/1910
Record Daily Highs and Warm Lows for April 1
Site High/Year(s) Set Warm Low/Year(s) Set
DCA 88/1978 64/2016
BWI 88/1978 62/2016
IAD 85/1978 64/2016
DMH 90/1978 69/1998
NAK 87/1978 60/1998
HGR 84/1978 60/1912
MRB 85/1943 58/2016
CHO 88/1978 68/1998
=========================================================
Period of Record (POR) context...
.Washington DC area (DCA)...
Weather records for the Washington DC area have been recorded
at what is now Ronald Reagan Washington National Airport (KDCA)
since 1941. The official weather record consists of that data
back to 1945, and observations taken in downtown Washington from
1871 to 1944. Temperature records for the Washington DC area
extend back to January 1872.
.Baltimore MD area (BWI)...
Weather records for the Baltimore MD area have been recorded at
what is now Baltimore/Washington International Thurgood
Marshall Airport (KBWI) since 1950. The official weather record
consists of that data back to 1950, and observations taken in
downtown Baltimore from 1871 through 1949. Temperature records
for the Baltimore MD area extend back to July 1872.
.Sterling-Dulles Airport VA area (IAD)...
Weather records for the Sterling-Dulles Airport VA area have
been recorded at what is now Washington Dulles International
Airport (KIAD) since 1960. The official record consists solely
of data recorded at the airport.
.Baltimore Downtown MD area (DMH)...
Weather records for the Baltimore Downtown MD area have been
recorded at what is now the Maryland Science Center (KDMH)
since 1999. The official weather record consists of that data
back to 1999, and observations taken in the City of Baltimore
from July 1950 through 1998. Data is missing from June 3 of 2020
through August 14 of 2022 when the observing system had to be
removed due to a large construction project.
.Annapolis MD area (NAK)...
Weather records for the Annapolis MD area have been recorded at
what is now the Annapolis U.S. Naval Academy (KNAK) since
October 11 of 2001. The official weather record consists of that
data back to 2001, and observations that were taken between the
Annapolis U.S. Naval Academy and the Annapolis Police Barracks
from July of 1894 through October 10 of 2001.
.Hagerstown MD area (HGR)....
Weather records for the Hagerstown MD area have been recorded at
what is now Hagerstown Regional Airport (KHGR) since October of
1998. The official weather record consists of that data back to
October of 1998, and observations taken one mile east of
Hagerstown from 1899 through September of 1998.
.Martinsburg WV area (MRB)...
Weather records for the Martinsburg WV area have been recorded
at what is now Eastern West Virginia Regional Airport/Shepherd
Field (KMRB) since 1938. The official weather record consists of
that data back to 1944, and observations taken in downtown
Martinsburg from 1891 through 1943.
.Charlottesville VA area (CHO)...
Weather records for the Charlottesville VA area have been
recorded at what is now Charlottesville-Albemarle Airport (KCHO)
since April 20 of 1961. The official weather record consists of
that data back to April 20 of 1961, and observations taken two
miles west of downtown Charlottesville from 1983 through April
19 of 1961.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until noon EDT Wednesday for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until noon EDT Wednesday for ANZ530>543.
&&
$$
DISCUSSION...ADS/KJP/SRT
AVIATION...ADS/SRT
MARINE...ADS/SRT
NWS LWX Office Area Forecast Discussion