Wheaton, Maryland 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

961
FXUS61 KLWX 120744
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
Issued by National Weather Service State College PA
344 AM EDT Thu Jun 12 2025

.SYNOPSIS...
High pressure will remain nearby through this afternoon before
shifting offshore tonight. A cold front will slowly approach
the area Friday through Saturday before stalling out nearby
early next week. Unsettled conditions are expected during this
time.

&&

.NEAR TERM /THROUGH TONIGHT/...
Patchy fog is expected early this morning, especially in the
Virginia Piedmont and in rural areas east of Interstate 95 where
surface dewpoints are a little higher. The probability for
widespread dense fog is low.

Upper-level smoke from distant Canadian wildfires may filter
the sunshine a little, but plenty of sunshine is still expected
today.

Weak high pressure will remain nearby through this afternoon
before shifting offshore tonight. At the same time, weak upper-
level ridging will build overhead combining with sunshine to
cause a hot afternoon. Highs will be in the upper 80s to lower
90s for most areas. Humidity will creep up a bit compared to
Wednesday, but still remain on the lower side with dewpoints in
the 50s and 60s. Heat indices will top off in the lower to
middle 90s near and east of 95 into central Virginia with 80s to
near 90 elsewhere (cooler in the mountains).

More dry conditions are expected tonight, but it will be
several degrees warmer compared to recent nights. Lows will
drop into the mid/upper 60s to mid 70s (upper 50s to lower 60s
in the high elevation valleys).

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The subtropical ridge will continue to build over Florida into
the Atlantic and surface high pressure will strengthen over the
Atlantic as a result. At the same time, upper-level low pressure
in the southern stream of the jet will shift east from the
Plains into the Midwest/Tennessee Valley for Friday.

Plenty of moisture will stream into the area Friday due to a
southerly low-level flow around the Atlantic high and ahead of
the southern stream upper-level low. Latest guidance shows a
weak shortwave/jetmax getting sheared apart from the the larger
upper-level low and passing through the area Friday. This system
is showing some reflection at the surface in the form of weak
low pressure. The combination of increasing moisture, very warm
conditions, and added lift from the shortwave/low pressure
will likely cause showers and scattered thunderstorms Friday
afternoon and evening. A few stronger slow moving storms are
possible, causing the threat for heavy rain and gusty winds.

Convection should wane overnight Friday/early Saturday morning,
but plenty of moisture will remain in place and this may result
in low clouds/areas of fog.

The upper-level low will continue to approach Saturday through
Saturday night while a backdoor boundary approaches from the
northeast. Plenty of moisture will remain in place for more
showers and thunderstorms to develop (mainly during the
afternoon and evening). The latest EPS still shows PWATS progged
to be around 2 SD above normal, and this combined with an
unstable atmosphere suggests that storms may contain heavy
rainfall that leads to flooding. There is still some uncertainty
as to exactly where the backdoor boundary sets up, and
consequently where the best lift and instability will be for the
stronger storms to develop. Most of the 00Z guidance shows that
the best low-level convergence may set up near and to the south
and west of the Potomac River. The strongest storms appear to
be most likely across these areas, but will continue to monitor.

Convection should wane in coverage overnight Saturday, but a
few showers along with low clouds and areas of fog will likely
persist.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The backdoor boundary will likely stall out near the area Sunday
through Monday while the upper-level passes through the area.
This will likely cause more showers and thunderstorms, and there
is a threat for heavy during this time. Exact details remain
uncertain, but the heaviest rain will most likely set up near
and to the south/west of the backdoor boundary.

The upper-level low will move off to the east for Tuesday and
Wednesday, but a nearly zonal flow aloft will persist along
with additional weak disturbances passing through the area. This
means more unsettled conditions will persist with chances for
showers and thunderstorms (especially during the afternoon and
evening hours each day).

&&

.AVIATION /07Z THURSDAY THROUGH MONDAY/...
VFR conditions are expected through tonight along with light
winds. A few showers and thunderstorms are possible Friday
afternoon and evening. Low clouds and fog are possible overnight
Friday and IFR conditions are possible.

An unsettled pattern with the likelihood for showers and
scattered thunderstorms will persist for Saturday through
Monday. Low clouds and areas of fog are possible during this
time, especially during the nighttime and morning hours each
day, resulting in subVFR and possible IFR conditions.

&&

.MARINE...
Weak high pressure will remain nearby for today before moving
offshore tonight. Winds will remain light, but turning southerly
this afternoon into tonight. Southerly channeling will cause
wind gusts to approach SCA criteria over the open waters, but
confidence is too low for a headline at this time.

A southerly flow will usher in plenty of moisture Friday, and
this will increase the chances for thunderstorms. Some stronger
storms with gusty winds are possible during the afternoon and
evening hours. A backdoor boundary will approach the waters
Saturday and stall out nearby for early next week. More showers
are likely with possible thunderstorms during this time.

&&

.TIDES/COASTAL FLOODING...
The more sensitive tidal sites could continue to hit action
stage during the higher of the 2 high tide cycles the next
couple of days. But overall, anomalies will slowly drop.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Air Quality Alert until midnight EDT tonight for DCZ001.
MD...Air Quality Alert until midnight EDT tonight for MDZ008-011-
     013-014-504-506-508.
VA...Air Quality Alert until midnight EDT tonight for VAZ053-054-
     505-506-526-527.
WV...None.
MARINE...Air Quality Alert until midnight EDT tonight for ANZ530.

&&

$$

SYNOPSIS...BJL
NEAR TERM...BJL
SHORT TERM...BJL
LONG TERM...BJL
AVIATION...BJL
MARINE...BJL
TIDES/COASTAL FLOODING...BJL