Area Forecast Discussion
Issued by NWS Sterling, VA

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963
FXUS61 KLWX 180051
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
851 PM EDT Fri Oct 17 2025

.SYNOPSIS...
Surface high pressure will gradually slide offshore through Saturday
as a potent trough of low pressure and surface cold front approach
the region. The cold front pushes through the area late Sunday into
early Monday morning bringing the next chance of measurable rainfall
along with windy conditions. High pressure briefly returns Tuesday
before another weak front crosses for the middle of next week.

&&

.NEAR TERM /THROUGH SATURDAY/...
Not as chilly tonight due largely in part to increasing high clouds
as a weak piece of energy slides north of the area. Lows will range
from upper 40s and low 50s over the ridges/metros with mid 30s in
the deeper sheltered valleys. Dry conditions will prevail with high
pressure nearby. Winds will remain light and variable with high
pressure gradually sliding toward the southeast U.S coast Saturday.

High pressure will continue off the NC/SC coast Saturday allowing
for south to southwesterly return flow across the region. Clouds
will start the day with sunny to mostly sunny skies Saturday
afternoon. High temperatures will warm into the upper 60s and low
70s in most locations. Areas west of I-81 and downslope of the
Alleghenies could see highs in the mid 70s to low 80s. Winds will
remain light out of the south and southwest at 5 to 10 mph.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/...
A potent low will move into the Great Lakes Saturday night into
Sunday morning and a cold front will approach from the west during
this time. A southerly flow will increase, allowing for mild
conditions. Moisture will begin to increase causing more clouds, but
dry conditions will most likely persist.

The cold front will slowly pass through the area from west to east
later Sunday afternoon into Sunday evening. Showers are expected to
develop with the frontal passage west of the Blue Ridge Sunday
afternoon, and east of the Blue Ridge Sunday night. The upper-level
trough axis is expected to swing toward a negative tilt around the
time of the frontal passage. This means forcing will be strong along
with a strong wind field aloft. Therefore, a line of gusty showers
is most likely to develop late Sunday afternoon into Sunday evening
along and just ahead of the cold front. With a very strong wind
field aloft, it is not out of the question for some of these winds
to mix down, causing a threat for damaging wind gusts. However,
confidence is low at this time due to limited instability.
Additional showers are possible overnight behind the cold front as
the negatively tilted upper-level trough passes through. Some
guidance is indicating a closed upper-level low can develop. If so,
the showers will be more widespread during the overnight hours.

Shower activity could linger into Monday in northwest flow as the
front works east with the resultant closed low departing for eastern
Canada.  Skies will gradually clear Monday afternoon with breezy
conditions expected as the front pushes east and high pressure
returns from the southeast U.S. Wind gusts of 25 to 35 mph are
expected.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
Strong cold front should have pushed east of the area early Monday
morning with gusty post-frontal NW winds. Weak sfc high pressure
builds in by the end of Monday. Another potent trough/closed low
traverses the Mid-Atlc area Tue night bringing light rain showers
Tuesday afternoon and evening with mountain rain showers
continuing in favorable upslope flow and even perhaps a
snowflake mixed in at times over the highest elevations as 850
mb temps drop between 0C and +2C. Broad trough pattern persists
for the second half of next week keeping near normal to below
normal temperatures.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions are expected to continue through Sunday morning. SOme
high clouds will pass through the area late tonight with light and
variable winds expected. High pressure will keep things dry as it
shifts off the southeast U.S coast Saturday. Winds will turn to the
south and southwest at less than 10kts.

Stronger southerly winds are expected ahead of a cold front Sunday
with gusts around 25 to 35 knots most likely. Showers are expected
with the cold front later Sunday afternoon through most of Sunday
night. A wind shift to the west and northwest is expected behind the
cold front late Sunday night. Sub-VFR conditions are possible in
showers Sunday night early Monday

Gusty post-frontal northwest winds Monday, which diminish by Monday
evening as high pressure returns from the south. VFR conditions
return Tuesday into Wednesday despite a dry cold front passing
through the region. This front will lead to another round of gusty
winds for the middle of next week.

&&

.MARINE...
Sub-SCA conditions are expected for the remainder of this evening
into Saturday. Winds will decrease out of the north before becoming
light and variable overnight into early Saturday morning. Southerly
winds will develop Saturday, but wind speeds should remain below SCA
criteria. Southerly winds may channel up the Bay and lower Tidal
Potomac Saturday night, and a Small Craft Advisory may be needed for
those areas. Stronger southerly winds are expected Sunday into
Sunday evening ahead of a cold front. A Small Craft Advisory will be
needed. Winds may even approach gale-force, but confidence is lower
due to the relatively cooler waters. Winds will turn to the
northwest behind a cold front late Sunday night, and an SCA will be
needed.

Showers will increase in coverage, especially Sunday night. A line
of heavier showers and perhaps a thunderstorm, along the cold front
may cause gusty winds, and Special Marine Warnings may be warranted.
This is most likely to occur late Sunday evening into SUnday night.

SCA conditions will likely continue throughout most of Monday in
post-frontal west to northwest flow. Winds decrease back below sub-
SCA levels Monday evening into TUesday as high pressure returns from
the south. Additional SCA conditions are possible by the middle of
next week as another front passes through.

&&

.TIDES/COASTAL FLOODING...
Higher anomalies in the southern portion of the Chesapeake Bay
will surge northward tonight, and this may cause minor tidal
flooding for sensitive areas (Annapolis) with the high tide
cycle tonight.

A southerly flow will develop Saturday and strengthen Sunday.
This will continue to increase tidal anomalies along with the
fact that a new moon is approaching on the 21st. Minor tidal
flooding is expected for sensitive areas Saturday into Saturday
night, and for most areas Sunday into Sunday night. There is the
potential for moderate tidal flooding around Annapolis with the
high tide cycles Sunday afternoon and Sunday night. Will
continue to monitor.

&&

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

&&

$$

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