Area Forecast Discussion
Issued by NWS Sterling, VA
Issued by NWS Sterling, VA
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FXUS61 KLWX 140732
AFDLWX
Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
332 AM EDT Mon Sep 14 2026
.WHAT HAS CHANGED...
Made some adjustments to today`s wind forecast as the models
were underdone with the strength of the post-frontal
northwesterlies. Otherwise, the forecast remains on track being
dry through mid-week before shower chances return on Thursday.
&&
.KEY MESSAGES...
- 1) Canadian high pressure will bring dry conditions with low
humidity to start the work week.
- 2) Warm and dry conditions expected through Thursday; showers
possible along a cold front at the end of the week.
&&
.DISCUSSION...
KEY MESSAGE 1...Canadian high pressure will bring dry conditions
with low humidity to start the work week.
What remains of showers that tracked across western Maryland
have since fallen apart in the last few hours. Scattered mid to
high clouds remain in the wake across locations east of the Blue
Ridge. Although drier air aloft has begun to move in, the
GOES-19 nighttime microphysics channel and surface observations
show stratus clouds developing along/west of the Alleghenies.
This will likely persist during the next few hours before drier
air across the Ohio Valley tracks into the local area. Until
this occurs, a seasonably mild and humid air mass remains over
the region early this morning. Current temperatures range from
the mid 60s to mid 70s, with dew points sitting in the mid 60s
to low 70s. The near saturated boundary layer has fostered the
development of some patchy fog, particularly around Fauquier and
Prince William counties. However, expect this to erode ahead of
sunrise.
A cold front currently nearing the Allegheny Front is forecast
to quickly sweep through the region early this morning. By mid-
morning, this boundary should be down around the Virginia
Tidewater area. In the wake, a rather strong dome of Canadian
high pressure works its way eastward from the Great Lakes. Over
the next couple of days, this frontal zone is to settle along
the southeastern U.S. coast while a 1028-mb ridge tracks through
New England. This will favor abundant sunshine, dry weather, cooler
temperatures, as well as much less humidity. In fact, dew points
temperatures are likely to drop into the mid/upper 40s. Daily
highs through Tuesday should be in the mid 70s to low 80s (60s
to low 70s across the mountains). The dry nature of the air mass
will support cool overnight periods, particularly tonight. With
the ridge axis right over the northeastern U.S., forecast lows
tonight will fall into the upper 40s to mid 50s. The I-95 urban
corridor could stay slightly milder being in the upper 50s.
Among the days ahead, today should prove to be the breeziest
given the tight gradient formed by the departing front and Great
Lakes high pressure. Northwesterly gusts up to 20 to 25 mph are
expected this afternoon, possibly to near 30 mph in a few spots.
Expect winds to drop off after dark with the decrease in
boundary layer mixing. Winds turn lighter by Tuesday with high
pressure in place. By mid-week, this ridge eventually begins to
shift off the Atlantic coast. This will support a gradual warm
up as winds return to southerly. Wednesday`s forecast highs push
back into the mid/upper 80s, with mainly 70s for the mountains.
Despite an uptick in humidity, the pattern does remain dry.
KEY MESSAGE 2...Warm and dry conditions expected through
Thursday; showers possible along a cold front at the end of the
week.
A strong upper ridge builds over the region during the middle
portion of the week supporting very warm and dry conditions. Not
looking at any record highs since records are in the mid 90s. The
ridge begins to flatten during the second half of the week as it
starts feeling pressure from a deepening trough over Hudson Bay. A
front is expected to progress southward at the end of the week and
bring chances of showers and thunderstorms. While we should start
seeing a cooling trend next weekend, temperatures still look to be
above normal. However, there has been noticeable model run-to-run
changes and large spread seen in temperatures for next weekend which
decreases confidence in the temperature forecast.
&&
.AVIATION /06Z MONDAY THROUGH FRIDAY/...
Aside from a few hours of patchy fog around KCHO early this
morning, VFR conditions are expected the next few days. Behind a
cold front that pushes through shortly, winds will shift over to
northwesterly while increasing in strength. Late morning to
afternoon gusts should reach 20 to 25 knots which comes with a
marked decrease in clouds. Such gusts gradually drop off into
the evening to overnight hours. Winds turn lighter by Tuesday
with Canadian high pressure centered across New England. A dry
forecast persists into Wednesday while this ridge slowly pulls
away from the coast which favors a return to southerly flow.
Fair weather conditions expected through Thursday and Friday.
&&
.MARINE...
A cold front currently pushing eastward from the Alleghenies
will eventually lead to increasing winds over the waterways.
This brings a shift to northwesterly flow along with gusts of 20
to 25 knots, occasionally to near 30 knots at times. Small Craft
Advisories are in effect for all waters through the mid-evening,
while continuing into the night over the southern waters. For
the remainder of Tuesday into Wednesday, the weaker gradients
accompanying the Canadian high pressure will favor gusts of
around 5 to 10 knots.
SCA conditions are possible again during the second half of
the week (i.e Thu afternoon into Fri morning).
&&
.TIDES/COASTAL FLOODING...
Tide levels are beginning to fall as anomalies have dropped over
a half foot in the past 6 to 12 hours. The post-frontal
northwesterly winds should further lower anomalies today. A
gradual rise in water levels is expected by late Tuesday as high
pressure pulls away from the Eastern Seaboard. This again pushes
a number of sites into Action stage during the higher of the two
astronomical high tides on late Tuesday/early Wednesday.
&&
.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Small Craft Advisory until 10 PM EDT this evening for MDZ008.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 10 PM EDT this evening for
ANZ530>533-535-536-538>542.
Small Craft Advisory until 7 AM EDT Tuesday for ANZ534-537-543.
&&
$$
DISCUSSION...LFR/BRO
AVIATION...LFR/BRO
MARINE...LFR/BRO
TIDES/COASTAL FLOODING...BRO