Columbia, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

934
FXUS61 KLWX 130732
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
332 AM EDT Wed Aug 13 2025

.SYNOPSIS...
Heat, humidity, and diurnal thunderstorm chances will continue to
increase through Thursday as high pressure pushes offshore and a
weak front approaches from the Ohio River Valley. The front will
pass through the area Thursday night with high pressure
returning for the start of the weekend. Another front looks to
cross the area Sunday into early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A cluster of showers and thunderstorms are moving east across
eastern West Virginia and far western Maryland early this
morning. Lightning and brief downpours are expected with this
cluster. This convection is expected to weaken before reaching
the Shenandoah Valley before daybreak.

As today continues, an approaching front will initiate
additional showers and thunderstorms across western and
northwestern zones later this morning and then across much of
the Mason-Dixon region during the afternoon into early this
evening. The Storms Prediction Center has our region from just
south of I-66 and areas to the north to the Pennsylvania line in
a Marginal Risk for Severe Thunderstorms today and tonight.
The threats will be damaging winds, hail and very heavy
rainfall. Highs today will reach the upper 80s to lower 90s in
the warmest locations.

As showers and thunderstorm continue this evening before
weakening and becoming more isolated overnight, the cold front
will stall near or just to our south. Lows tonight in the lower
70s for most.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A summertime pattern persists through Thursday with heat,
humidity, and daily chances for showers and thunderstorms in the
forecast. A potent longwave trough crosses through Quebec while
the stalled front across our south will be the focal zone for
developing showers and thunderstorms Thursday afternoon and
early evening.

Afternoon highs each day in the upper 80s to near 90F, with heat
indices in the mid to upper 90s to around 100F. Overnight lows will
be muggy in the low to mid 70s.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Not much of a change in the overall pattern for the upcoming weekend
and early next week. The subtropical ridge over the southeastern U.S
should strengthen/build with 500 mb heights hovering between 589-592
dm. Meanwhile, a cold front will dissipate over the area this
weekend. By the weekend, t-storm chances become more suppressed with
the building upper level ridge. Any convection looks to be terrain
based or relegated to the initiation of the bay/river breeze. High
temperatures Saturday should push into the mid 80s to low 90s, with
mountain locations in the mid 70s to low 80s. Low temperatures will
fall into the low to mid 60s over the mountains with mid 60s to low
70s further east toward the Baltimore/Washington DC metro areas.

Sunday brings on more heat and humidity ahead of a encroaching cold
frontal boundary from the Great Lakes and northern Ohio River
Valley. High temperatures will climb back into the low to mid 90s
for most with heat index values hovering between 95-100 degrees. A
few spotty showers or t-storms cannot be ruled out especially over
the mountains and northern portions of the forecast area given the
amplified northern stream.

Slightly higher chances for diurnally driven shower and thunderstorm
chances exists for the early and middle part of next week. Current
guidance continues to show a fairly amplified northern stream.
Ridging high pressure remains over the southeastern U.S with a
secondary ridge over central and eastern Canada. Caught in between
the two upper level ridges is a decent frontal zone extending over
the northern tier of the U.S. Within this frontal zone will be a
series of fronts that will drop south from the Great Lakes/Ohio
River Valley Monday through Wednesday next week. The first front
looks to cross the area Monday before washing out over the central
and southern part of the forecast area Tuesday. Another front will
follow midweek. With the several fronts crossing expect an uptick of
shower and thunderstorm chances mainly during the afternoon/evening
hours.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
Patchy ground fog and low stratus around CHO/MRB terminals could
lower conditions to LIFR. This fog and cloud cover will
dissipate mid-morning this morning. Showers and thunderstorms
will develop around midday today and linger through this
evening. Showers and thunderstorms will again develop on
Thursday with a front nearby. These could produce brief periods
of sub- VFR conditions at any terminal. Most of the activity
should dissipate in the evening each day.

A weak cold frontal boundary will lead to some temporary reductions
Friday afternoon and evening due to showers/thunderstorms.
Additional reductions are possible during the afternoon and evening
hours this weekend as the front dissipates nearby. Convection
overall will be fairly spotty this weekend given the strengthening
subtropical ridge overhead. Winds Friday will be out of the east and
southeast Friday at less than 15 kts.

Convection overall will be fairly spotty this weekend given the
strengthening subtropical ridge overhead. Winds east and
southeast Saturday at less than 15 kts. Winds will switch back
south and southwest Sunday into Monday.

&&

.MARINE...
The main concern for mariners will be from this afternoon and
evening thunderstorm activity that could return to the forecast
and continue into Thursday. Special Marine Warnings may be
needed at times for strong gusty winds. A cold front will also
cross the area, though it will only bring a brief wind shift.

Sub-SCA level winds will continue through the period. Winds will
remain light out of the east and southeast Friday at less than
15 kts. This is due in part to a dissipating frontal boundary
over the region.

Sub-SCA level winds will continue through the period. Winds will
remain light out of the east and southeast Saturday at less than 15
kts. This is due in part to a dissipating frontal boundary over the
region. Winds will switch to the south and southwest Sunday and
Monday at less than 15 kts. Some southerly channeling remains
possible Monday into Tuesday over the open waters, but overall
confidence is low.

&&

.TIDES/COASTAL FLOODING...
Elevated tidal anomalies look to continue today given the
recent full moon and light winds. While minor tidal flooding is
not expected, some cycles could go into Action stage during the
high astronomical tides (especially at Annapolis and perhaps
Dahlgren/Alexandria).

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

SYNOPSIS...LFR
NEAR TERM...LFR/KLW
SHORT TERM...KRR
LONG TERM...CPB/EST
AVIATION...KLW/CPB/KRR
MARINE...KLW/CPB/KRR
TIDES/COASTAL FLOODING...KLW