726
FXUS61 KLWX 190630
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
230 AM EDT Wed Mar 19 2025

.SYNOPSIS...
A quick moving cold front brings renewed chances for showers
and perhaps a few thunderstorms Thursday. Windy conditions are
expected in the wake of the front Thursday night into Friday as
brief high pressure returns. Another weak front moves through
the region this weekend and again early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Mid-level ridging along the Eastern Seaboard today helps to maintain
dry conditions as temperatures rise to the low to mid 70s for most
of the area. A few spots in central VA could reach the upper 70s.
Even though southerly flow begins to increase today, the airmass
remains very dry with dew points in the mid 20s to lower 30s. This
is going to result in a fire weather threat across the area this
afternoon (see fire weather section below). An approaching cold
front from the west results in increasing cloud cover tonight,
though most of the precipitation looks to hold off until Thursday.
Lows tonight in the 40s to low 50s.

&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
A broad upper trough stretching over much of the eastern CONUS is
set to move across the Mid-Atlantic Thursday into early Friday. An
associated cold front will bring widespread showers and possibly a
few thunderstorms through Thursday afternoon. Instability ahead of
the front looks meager, so not expecting much for a severe weather
threat at this time. Warm conditions Thursday as highs reach mid 60s
to lower 70s.

There is still good model consensus for a wave of surface low
pressure to develop over the area along the frontal boundary, then
deepen as it moves to the northeast. This is likely to result in two
things: 1) some localized higher rainfall totals along and east of I-
95 where forcing and moisture transport are maximized; 2) a quickly
tightening pressure gradient that quickly onsets windy conditions
on the backside of the departing front.

Due to the progressive nature of the front, heavier precipitation is
likely only to last for 3-6 hours at any location, with mostly low
rainfall rates otherwise. Dry conditions return in wake of the front
Thursday evening through Friday. Turning colder as lows plummet to
the 30s Thursday night, with below freezing temps west of I-81.

As temperatures drop, upslope mountain rain showers transition to
all snow Thursday night in the Alleghenies. A quick 1-2" of snow is
likely, especially along/west of the Allegheny Front. These snow
showers come to an end Friday morning.

In terms of winds, breezy northwest winds develop Thursday evening
along and west of the Blue Ridge, with gusts of 25-35 mph in the
valleys and up to 40-50 mph along the ridges. East of the Blue
Ridge, winds begin to increase late in the evening. The strongest
winds are forecast from early Thursday morning (4-5AM) through
Thursday afternoon. Currently, wind gusts of 35-45 mph are forecast
for most of the area, and up to 55 mph in the mountains. The climo-
wind favored areas could approach Wind Advisory conditions, with
these Advisories likely needed for portions of the Alleghenies and
Blue Ridge Mountains.

Winds begin to diminish Friday afternoon into the evening as the
pressure gradient over the area slackens due to the surface low
moving farther away. Seasonal temperatures in the 50s to low 60s
Friday afternoon, then dropping to the 30s Friday night.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
Synoptically, looking at more of a zonal and progressive flow
pattern aloft this weekend into early next week. This will allow
several frontal systems to traverse the region along with near
normal to slightly above normal temperatures to prevail throughout
the extended period.

At the surface, high pressure will continue off the southeast U.S
coast Saturday while low pressure ejects north and east from the
Ohio River Valley into the eastern Great Lakes region. The
associated weak cold frontal boundary with this system looks to pass
just to the north of the region Saturday morning and afternoon
before washing out nearby. Showers will accompany this front mainly
north of I-70 and along/west of the Allegheny Front where the best
forcing resides. Most locations will remain dry as the front looks
moisture starved compared to past model runs over the last few
cycles. A little snow is also possible on the higher peaks of the
Alleghenies above 3500 feet where temperatures will sit close to
freezing as precipitation arrives Saturday morning into Saturday
midday. Southerly flow will ensue behind the departing high and
ahead of the incumbent front yielding high temperatures back into
the upper 50s and low to mid 60s despite added cloud cover. Drier
conditions are expected Saturday night into Sunday as brief high
pressure builds back into the region. Skies will clear as a result
with lows Saturday night in the upper 20s and low to mid 30s.
Seasonable high temperatures can be expected Sunday with highs in
the mid to upper 50s (mountains 40s).

Precipitation chances return Monday as a low pressure system over
the Upper Midwest/Great Lakes approaches the region. The occluded
low looks to meander from the upper Midwest into the Great Lakes
late Sunday night into Monday. The associated warm front with this
system will lift into the area early Monday followed by the
associated cold front late Monday into Tuesday. Meanwhile, high
pressure will sit off the New England coast wedging down the eastern
spine of the Appalachians while low pressure remains locked over
eastern Canada sending additional waves of shortwave energy south
and east toward the region. The combination of onshore flow from the
wedging high and incoming shortwave energy from the west will yield
a period of unsettled conditions early to mid next week. High
confidence for widespread rain chances appears to be on Monday
although shower chances (albeit lower/less spatial coverage) will
exists through midweek.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions are expected through tonight in steady southerly
flow. A cold front is set to move across the area Thursday, bringing
showers to all terminals during the late morning to afternoon hours.
This could bring some periods of sub-VFR conditions, mostly from
reduced visibility. Precipitation comes to an end by Thursday
evening.

Northwest winds quickly increase behind the front Thursday evening,
and become stronger Friday morning into Friday afternoon. Wind gusts
of 25-30 knots Thursday night peak at 35-40 knots from Friday
morning to early Friday afternoon. Winds diminish by Friday evening
as winds turn southwest to south Friday night.

A weak front will bring a few showers and perhaps brief periods of
sub-VFR mainly west of the I-95 terminals Saturday morning into
Saturday afternoon. West to southwest winds will gusts up to 20 kts
ahead of and in the wake of the boundary Saturday before diminishing
Sunday as high pressure builds nearby. VFR conditions are expected
as a result Sunday with sub-VFR conditions Monday and Tuesday as a
stronger front crosses the region.

&&

.MARINE...
South to southeast winds slowly increase throughout the day over all
of the waters, eventually reaching SCA levels tonight. During the
day today, some occasional gusts to 20 knots are possible in the
afternoon to evening hours.

Hazardous marine conditions are likely over all of the waters
Thursday through most of Friday due to a cold front crossing the
area, then strong winds developing behind it. A Gale Watch remains
in effect from Thursday night through Friday afternoon, with
increasing confidence for wind gusts of 35-40 knots. Gale conditions
come to an end by the middle of Friday afternoon, then SCA
conditions continue through Friday night.

A weak front will deliver SCA conditions to the waters late Saturday
morning into Saturday evening. Winds will switch from the southwest
to northwest with gusts up to 20 kts. Winds will slowly diminish
back below SCA levels Saturday night into Sunday as high pressure
briefly builds over the waters. Additional SCAs will be needed early
next week as a strong cold front crosses the waters Monday into
early Tuesday.

&&

.FIRE WEATHER...
The combination of low humidity and gusty winds will result in a
greater risk of adverse fire behavior and rapid fire spread from
late this morning through early this evening.

Relative humidity values will drop 20 to 25 percent across most of
the area this afternoon, with values of 15 to 20 percent in the
Alleghenies. Southeast winds around 10-15 mph gust between 20 to 25
mph. For the ridges, higher gusts up to 35 mph are expected.
Temperatures this afternoon reach the 70s at most locations.

Please refer to your local burn permitting authorities on whether
you may burn outdoors on Saturday. If you do burn, use extreme
caution since fires can increasingly escalate under these conditions.

A cold front crossing the area on Thursday could bring some wetting
rains, though the highest rain amounts are forecast to be east of
the Blue Ridge.

Friday has the potential to be a high fire danger day depending on
how much of a wetting rain occurs on Thursday. Regardless, windy
conditions are expected behind the cold front from early Friday
morning through Friday evening. Northwest winds gust around 30-40
mph and up to 45-55 mph in the mountains. RH values are forecast to
drop to 20-30 percent areawide, with lower RH values possible.

&&

.TIDES/COASTAL FLOODING...
Anomalies will slowly climb heading into midweek as southerly flow
increases ahead of an approaching cold frontal boundary. Some sites
may approach action stage by the high tide cycle Thursday morning
into Thursday afternoon. The best opportunity for minor flooding
appears to be at Annapolis and DC Waterfront. We`ll continue to
monitor the trends amongst the ensemble guidance over the coming
days ahead. Any tidal flooding will be short lived with offshore
flow returning late Thursday into Friday.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...Gale Watch from Thursday evening through Friday afternoon for
     ANZ530>543.

&&

$$

SYNOPSIS...EST
NEAR TERM...KRR
SHORT TERM...KRR
LONG TERM...EST
AVIATION...KRR/EST
MARINE...KRR/EST
FIRE WEATHER...KRR
TIDES/COASTAL FLOODING...EST