Area Forecast Discussion
Issued by NWS Sterling, VA

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000
FXUS61 KLWX 120801
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
401 AM EDT Fri Apr 12 2024

.SYNOPSIS...
Low pressure will track into Southern Canada today, while an
associated cold front progresses off to our east. A reinforcing
cold front will move through tonight. High pressure builds to
our south tomorrow. A weak area of low pressure will pass to our
north Sunday night into Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
A deep area of low pressure continues to track into the Great
Lakes early this morning. A trailing cold front extends to its
south, reaching to near the crest of the Appalachians as of 330
AM. Showers are present on radar across much of the forecast
area at the moment, but are expected to trend down in coverage
toward daybreak behind the aforementioned cold front, which
will work across the area from west to east between now and
shortly after daybreak. A few showers, and potentially even a
thunderstorm or two may redevelop across the area this
afternoon as the system`s upper trough axis tracks overhead. The
greatest chance for a brief shower or storm should be across
northern Maryland. The main weather story today will be wind.
Wind Advisories have been issued for the mountains through the
day Saturday. Conditions will also be windy further east, but
closer to the Wind Advisory threshold of 40 knots, as opposed to
comfortably above it in the mountains. At the moment, frequent
gusts of 30-40 knots out of the west-southwest appear likely
during the day today across most of the forecast area. If
condfidence in 40 knot gusts increases, the Wind Advisory may
potentially need to be expanded further eastward. High
temperatures today should reach well into the 60s for most.

A reinforcing cold front will move through the area tonight. The
strongest wind field will move in behind this front. It`s
likely that many locations will remain windy through the night,
especially in the mountains. Lows overnight should be in the 40s
to lower 50s for most, with 30s in the mountains. A few upslope
snow showers may be possible late tonight across the highest
terrain (over 3000 ft). In those locations, a brief coating of
snow may be possible overnight.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Low pressure will continue to lift off to our northeast on
Saturday, while high pressure simultaneously builds to our
south. This will maintain a strong pressure gradient across the
area, which will in turn keep conditions quite windy. Wind
Advisories remain in effect through the day Saturday in the
mountains, and a potential further east extension of that
advisory may eventually be needed. For the time being the
current forecast calls for frequent gusts of 30-40 knots out of
the west-northwest, with 40+ knot gusts in the mountains.
Temperatures will remain mild, with high temperatures in the 60s
for most (50s mountains). Clouds will tend to clear out over
the course of the day as upper level troughing progresses off to
our east and large scale subsidence increases overhead.

Heights will continue to rise aloft on Sunday as flow turns more
zonal in nature. A weak shortwave disturbance and associated
area of low pressure will pass off to our north Sunday night.
This disturbance may potentially spark the development of a few
showers or thunderstorms Sunday afternoon into Sunday night.
Southwest winds will transport a notably warmer airmass into the
region, with high temperatures reaching well into the 70s to
near 80 for most.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
Upper level ridge will gradually build over the East during the
first half of next week cresting over the area Wednesday. This will
lead to a gradual warm up with temperatures rising into the mid 70s
potentially reaching as high as 80. A weak backdoor front will
make into the area Monday, but won`t have much effect in
sensible weather. The front retreats north of the area by
Wednesday. An upper trough pushing across the Great Lks Thu will
push a weak cdfnt across the area next Fri. Looks like Wed and
Thu are the only two days when there is enough instability to
support thunderstorms. Overall, next week looks a lot quieter
than this week.

&&

.AVIATION /08Z FRIDAY THROUGH TUESDAY/...
Conditions are generally either MVFR or VFR at the terminals early
this morning. Showers continue to linger across the area, but
heavier downpours have moved out of the area. A cold front will move
across the area late tonight, causing winds to shift from the south
to the west-southwest for the day today.
Conditions will also improve to VFR for all behind the front.
Winds will become quite gusty out of the west southwest today, and
remain gusty out of the west-northwest tomorrow. Gusts of 30 to 40
knots should be common through Saturday afternoon. After overnight
showers move out, much of the day should remain dry.
However, a few showers and potentially even a stray thunderstorm may
develop this afternoon. The chance for a thunderstorm is far to low
to mention directly in the TAFs (around 10-20 percent).
Drier conditions are expected this weekend. It will remain breezy on
Sunday, with winds out of the southwest gusting to around 15-25
knots.

No sig weather is expected Mon and Tue.

&&

.MARINE...
Winds are southerly over the waters early this morning. A cold front
will move through around daybreak causing winds to turn west-
southwesterly. A reinforcing cold front will move through tonight,
causing winds to turn west-northwesterly tomorrow. Gale Warnings
remain in effect for all waters through the day tomorrow. Gusts to
near, or potentially even in excess of 40 knots will be possible
over the waters during that time. Additional SCAs will likely
be needed within southwesterly flow Saturday night into Sunday.

Winds will be on the light side through Wed morning with no SCAs
anticipated at this time.

&&

.TIDES/COASTAL FLOODING...
The highest tides are expected later this morning, and this is when
widespread minor to localized moderate tidal flooding would be most
likely.

Westerly flow should cause a decrease in tide levels this afternoon
into Saturday, though the flow is west instead of northwest which
may result in some residual elevated water levels sloshing around
the Chesapeake Bay and tidal Potomac River a little longer than is
typical behind a front.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until 8 AM EDT this morning for DCZ001.
     Coastal Flood Warning from 8 AM this morning to 5 PM EDT this
     afternoon for DCZ001.
MD...Wind Advisory until 6 PM EDT Saturday for MDZ001-501-502.
     Coastal Flood Advisory until 4 AM EDT early this morning for
     MDZ008.
     Coastal Flood Advisory until 2 PM EDT this afternoon for
     MDZ011.
     Coastal Flood Warning until 2 PM EDT this afternoon for MDZ014.
     Coastal Flood Advisory until 10 AM EDT this morning for MDZ016-
     018.
     Coastal Flood Warning until 10 AM EDT this morning for MDZ017.
     Coastal Flood Advisory until 9 AM EDT this morning for MDZ508.
     Coastal Flood Warning from 9 AM this morning to 6 PM EDT this
     evening for MDZ508.
VA...Wind Advisory until 6 PM EDT Saturday for VAZ503-504.
     Coastal Flood Advisory until 10 AM EDT this morning for VAZ057.
     Coastal Flood Advisory until 5 PM EDT this afternoon for
     VAZ054.
WV...Wind Advisory until 6 PM EDT Saturday for WVZ501>506.
MARINE...Gale Warning until 6 PM EDT Saturday for ANZ530>543.

&&

$$

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


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