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000
FXUS61 KLWX 131840
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
240 PM EDT Sat Apr 13 2024

.SYNOPSIS...
Low pressure will continue to lift northward into Canada today
as high pressure builds to our south. A weak area of low
pressure will track to our north on Sunday, eventually pushing a
weakening cold front southward through the area late Sunday
night into Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Winds will continue to remain gusty through much
of the day with dry and mostly sunny conditions for the
afternoon and evening hours. The low-level jet passed through
portions of the area earlier this morning, allowing winds to
lessen by about 10-15 mph at times, but they will remain
elevated through much of the day. Wind Advisories remain in
effect across areas mainly along and west of the Catoctin and
Blue Ridge Mountains through 6 PM this evening. Should winds
diminish faster, then the advisories may be canceled early but
there is still some uncertainty with this given the peak mixing
time of the day over the next several hours. Highs will continue
to climb into the low to mid 60s this afternoon for most aside
from the Allegheny Front, where 50s will be more common.

Winds should decrease rather abruptly this evening with loss of
daytime heating and resultant mixing. Skies will remain mostly
clear overnight, with temperatures dropping back into the 40s.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
Flow aloft will become more zonal in nature tomorrow, with a
broad belt of west-southwesterly flow extending from the Upper
Midwest toward the East Coast. A shortwave disturbance will
descend down in the west-northwesterly flow from the Great Lakes
toward Upstate NY. A weak area of low pressure will accompany
the shortwave, along with an attendant cold front which will
drop southward out of NY into northern PA Sunday afternoon.
Locally, it will be a warm day to the south of the boundary,
with temperatures climbing into the upper 70s to near 80 beneath
partly cloudy skies. Thunderstorms are expected to form near the
aforementioned frontal boundary up in PA Sunday afternoon. Much
of this activity is expected to remain to our north during the
daylight hours.

As we move into the evening and the first half of the
overnight, these storms are expected to drift southward along
with the frontal boundary, eventually reaching northern portions
of the forecast area. With loss of daytime heating, the trend
should be for these storms to gradually weaken as they move in
from the north, but a few stronger storms can`t be ruled out.
The environment will be an uncommon one for this part of the
country, with steep lapse rates of 7-8.5 C/km in place as an
elevated mixed layer moves in aloft. If storms do persist as
they track into the area, some instances of large hail may be
possible. SPC currently has portions of northern Maryland and
the West Virginia Panhandle outlooked in a Marginal Risk for
severe thunderstorms.

The frontal boundary will continue to drift southward across the
area on Monday. A few storms may try to form along the front
from central Virginia to southern Maryland Monday afternoon, but
conditions should remain dry for the vast majority of the
forecast area. High temperatures will range from the mid 70s
across northern Maryland to the lower 80s from central Virginia
to southern Maryland.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
A warm front will approach from the south Tuesday afternoon into
Tuesday night. Showers and perhaps a rumble of thunder could
accompany the front in parts of the region. High temperatures
will reach the middle 70s for most.

With a warm front moving into and across Pennsylvania Wednesday
and Wednesday night, a leeside trough of low pressure could setup
in our region and be aligned north to south. It is both behind
the warm front and ahead of and along this leeside trough that
additional showers and thunderstorms could develop during the
warmth of the day Wednesday afternoon and evening. Highs again
will reach the middle to upper 70s.

There could be a break in shower and thunderstorm chances Thursday
into Thursday night as weak high pressure develops on the west
side of the leeside trough. Most of any showers and
thunderstorms may be more focused near the Mason-Dixon region
through the course of the day on Thursday. Highs on Thursday
could reach the upper 70s to lower 80s.

By Friday, a cold front will trail an area of low pressure in the
Great Lakes and push across the region later in the day Friday into
Friday night. This cold front will increase our chances for showers
and thunderstorms again. Highs Friday, due to increased cloud cover
and increased coverage of showers and thunderstorms, will be a few
degrees less with temperatures reaching the lower 70s.

&&

.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
Gusty northwest winds will persist through the remainder of the
afternoon and early evening. Gusts 35-40 knots will be possible
at times near the terminals through 20-21z. Winds should
abruptly decrease further after dark. Winds Sunday will turn
out of the southwest, and may gust to around 20-30 knots at
times. Northwest winds are forecast for Monday, with gusts of
15-20 knots possible at times.

VFR conditions Tuesday through Wednesday. Sub-VFR conditions
possible in heavy downpours from showers and thunderstorms
Wednesday evening. Winds northeast then southeast 5 to 10 knots
Tuesday and Tuesday night. Winds south 10 to 15 knots gusts up
to 20 knots Wednesday. Winds southwest around 15 knots gusts 20 to
25 knots Wednesday night.

&&

.MARINE...
Gusty west-northwesterly winds will continue through the day
today. Gale Warnings remain in effect for all waters through 6
PM. There should be a fairly sharp drop off in winds this
evening, but SCA conditions will persist through around 02z
tonight before diminishing further. Small Craft Advisories will
likely be needed again Sunday in southwesterly flow. Sub-SCA
northwesterly winds are expected on Monday.

No marine hazards Tuesday through midday Wednesday. Small
craft advisories possible late Wednesday and Wednesday night.
Winds northeast becoming southeast 5 to 10 knots Tuesday and
Tuesday night. Winds southeast 10 to 15 knots early Wednesday, then
increasing south to southwest 15 to 20 knots late Wednesday and
Wednesday night.

&&

.TIDES/COASTAL FLOODING...
Amplified onshore flow will allow for anamolies to continue to
fall, with most tidal sites remaining below action stage.
Anomalies will continue to fall during this time. The change
from high anomalies yesterday to lower anomalies today will
cause a strong current during this time. Thereafter, water
levels are expected to remain below Minor flood stage for the
next several days.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...Wind Advisory until 6 PM EDT this evening for MDZ001-003-004-
     501-502.
VA...Wind Advisory until 6 PM EDT this evening for VAZ025>031-040-
     501-503>508-526.
WV...Wind Advisory until 6 PM EDT this evening for WVZ050>053-055-
     501>506.
MARINE...Gale Warning until 6 PM EDT this evening for ANZ530>543.
     Small Craft Advisory from 6 PM to 10 PM EDT this evening for
     ANZ530>543.

&&

$$

SYNOPSIS...KJP/ADM
NEAR TERM...KJP/ADM
SHORT TERM...KJP
LONG TERM...KLW
AVIATION...KLW/KJP/ADM
MARINE...KLW/KJP/ADM
TIDES/COASTAL FLOODING...LWX