Arlington, Virginia 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

454
FXUS61 KLWX 310037
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
837 PM EDT Mon Mar 30 2026

.WHAT HAS CHANGED...
Small Craft Advisories were extended through the day tomorrow.
Otherwise, no major changes were made to the forecast this
evening.

&&

.KEY MESSAGES...
- 1) Near record temps through Wednesday ahead of an approaching
  cold front that looks to bring showers and perhaps a few
  strong to severe thunderstorms.

- 2) A front will waver near the region during the second half
  of the week before being overtaken by a stronger cold front
  Sunday.

&&

.DISCUSSION...
.KEY MESSAGE 1...Near record temps through Wednesday ahead of an
approaching cold front that looks to bring showers and perhaps
a few strong to severe thunderstorms.

Synoptically, it`s predominantly zonal flow with high pressure
anchored offshore and a cold front slowly sinking south from the
Great Lakes and interior Northeast. This front will eventually push
into the Mid-Atlantic during the Wednesday into Wednesday night
timeframe. Ahead of the boundary will be some weak impulses and
increased isentropic ascent/warm air advection across the
region.

Turning much warmer Tuesday and Wednesday with temperatures expected
to push near record levels. Highs both days will punch into the
upper 70s and mid 80s with overnight lows in the mid 50s and low
60s. Shortwave ridging should keep most of the area dry Tuesday with
an isolated shower or t-storm mainly west of the Blue Ridge.

More widespread t-storm coverage is expected Wednesday afternoon and
evening as the cold front drops into the region. Some of the latest
CAMS and deterministic guidance have some morning convection
Wednesday which could hamper the severe threat in the afternoon.
The environment also appears capped above 700 mb given the
morning convection as well as increased mid and high level cloud
cover. A few things to note though would be modest 30-35 kts
(0-6 km shear) mainly along and north of I-66/US-50. There is
also a remnant plume of elevated mixed-layer (EML) air evident
in forecast soundings above a cap at 700 hPa. This results in
steepening mid-level lapse rates of 7-8 C/km. If enough low-
level heating and moistening take place, and the convergence
along either the approaching cold front or a pre-frontal trough
are sufficient, then the cap would likely break. Steep mid-level
lapse rates above the cap and steep low-level lapse rates below
the cap would then lend a threat to gusty winds with inverted-V
profiles. The severe threat may be tempered by modest low-level
downsloping flow and moisture, as well as height rises aloft in
spite of a shortwave shearing out to the north across PA.

SPC currently has much of the forecast area highlighted in a
Marginal risk for severe thunderstorms, while CSU learning
machine probs and NSSL probabilities have a 15-30 percent chance
for severe t-storms mainly along and north of I-66/US-50. If
severe weather were to occur, damaging winds and small hail
would be the primary concerns. Any threat would quickly diminish
Wednesday evening and night as the boundary sags south of the
area.


.KEY MESSAGE 2...A front will waver near the region during the second
half of the week before being overtaken by a stronger cold front
Sunday.

The forecast is narrowing a bit to the point where Thursday is the
most likely day for the backdoor front to be stalled near the area.
That front will have a very strong temperature contrast across it,
with cooler air in the 50s or lower 60s to the northeast and 80s to
the southwest. Thus there is still potential for large errors in the
current temperature forecast for Thursday. Even with the front
nearby, the strong upper ridge will remain in place off the
southeast coast, so shower and thunderstorm chances will remain
somewhat minimal.

The front will lift to the north Friday as another area of low
pressure moves from the Great Lakes toward the St. Lawrence Valley.
This will send temperatures back into the 70s and 80s across the
area. The trailing cold front will lag back to the northwest, so
there won`t be any immediate forcing for precipitation. Some showers
and thunderstorms may move in from the northwest, or develop along
the terrain which will be farthest away from the upper ridge.
There`s a small chance the front could backdoor into the area
Saturday, but most likely will stay to the north due to the upper
ridge and yet another low that will be moving into the Great Lakes.
Therefore, the highest chance of showers and thunderstorms Saturday
will again be in the mountains. Assuming the front remains to the
north, temperatures could be even warmer, with many areas pushing
the mid 80s.

The cold front will push through the area Sunday with a greater
chance of rain across the entire area. At this time, instability
looks fairly meager, so thunderstorms may be limited. Rain will
likely be out of the area by Monday, and temperatures will return
closer to seasonable values.

&&

.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
VFR conditions are expected to continue through Tuesday night
although a brief shower or isolated t-storm cannot be ruled out
at the terminals. LLWS appears likely overnight as a low level
jet pivots overhead. Outside of LLWS, breezy conditions will
remain with south to southwest gusts of 15 to 20 kts during the
overnight periods and 20 to 25 kts likely during the daytime
hours.

Sub-VFR conditions are expected to return Wednesday and Thursday as
a cold front sags through the region. The front will bring
widespread gusty showers and perhaps a few strong to severe
thunderstorms Wednesday afternoon and evening. Winds will shift
from the west and southwest back to the north and northwest
Thursday.

Sub-VFR ceilings are possible Thursday and Friday, especially
near and northeast of the Potomac River, as a front stalls
nearby. This front will return northward Friday with southerly
wind gusts to 20 kt possible. With the frontal zone near or just
north of the area, there could be showers and a few
thunderstorms at any time between Thursday and Saturday.

&&

.MARINE...
SCAs will continue through tonight for most of the waters.
Gusty south to southwest flow will remain given the gradient
between high pressure offshore and a slow moving cold front
approaching from the Great Lakes region. Additional SCAs have
been issued for all waters during the day Tuesday. SCAs may be
needed in the wake of the front with east to southeast flow late
Wednesday into Thursday.

Shower and thunderstorm chances return to the waters Wednesday
afternoon and evening as a cold front drops into the area. Wind
direction is uncertain Thursday as a front will be stalled near
the area. This front will lift back northward on Friday, and
southerly winds may near SCA criteria. The frontal zone will
likely remain north of the area Saturday as southerly flow
continues. While a few thunderstorms are possible at times
between Thursday and Saturday, it is unlikely that there will be
widespread strong thunderstorms based on the current forecast.

&&

.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 midnight EDT tonight for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ530>543.

&&

$$

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