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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KLWX 221450
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
1050 AM EDT Mon Apr 22 2024

.SYNOPSIS...
High pressure will build across the area today and Tuesday. A
cold front will move through Wednesday, with high pressure
building in again for the end of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Mid-morning update: Frost Advisories/Freeze Warnings from the
previous night have been allowed to expire. They have been
replaced with additional Frost Advisories/Freeze Warnings for
tonight. The only areas not under a Frost Advisory or Freeze
Warning tonight are Calvert and St. Mary`s Counties, as well as
higher elevations where the growing season hasn`t officially
started yet. Previous discussion follows...

The high will build toward the area today while the upper trough
pushes east. Mostly sunny skies are expected. While warmer than
Sunday, temperatures will still be a little below normal, in the
lower to mid 60s.

The high will build over the Carolinas tonight, leading to a
better chance of calm winds. Skies will remain clear until some
high clouds approach toward sunrise. While dew points will be a
little higher, they will remain in the lower 30s across much of
the area. Favorable radiational cooling conditions will result
in rural areas dropping into the mid to upper 30s while the
urban centers remain in the mid 40s. Additional Frost Advisories
are likely. A few spots could touch freezing in the Shenandoah
Valley and Culpeper Basin.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The surface high will push to the south and east Tuesday. Upper
troughing will dig into the Great Lakes late Tuesday, while low
pressure at the surface tracks across southern Canada. A
trailing cold front will extend southwestward across the Ohio
Valley. The daylight hours of Tuesday will remain dry but with
increasing mid and high clouds. A southerly flow will result in
warmer temperatures in the upper 60s and lower 70s. The cold
front will push toward the area Tuesday night before crossing
Wednesday. Showers will become likely along the Appalachians
Tuesday night. However, prospects for rain east of the mountains
are meager. A downsloping flow aloft combined with a glancing
shot of forcing and minimal moisture return ahead of the front
will tend to cause the showers to dissipate as they press east.
Those that do will produce less than a tenth of an inch of rain.
Some additional isolated to scattered showers could form during
the day on Wednesday as weak instability builds beneath the
upper trough axis. Gusty downslope flow (20-30 mph gusts) behind
the front will support continued warm conditions east of the
mountains where highs will be in the mid 60s to mid 70s.

High pressure of Canadian origin will build southeast across the
Great Lakes Wednesday night. Winds will remain somewhat elevated
through the night but cold advection will drop temperatures to
the 30s and lower 40s.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Two areas of high pressure will build into the region Thursday and
Friday, keeping the region dry. The first area of high pressure will
usher in cooler than average air on a northerly wind. Highs will
reach only the upper 50s to lower 60s. The second high will allow
for winds to quickly become east to southeasterly. These moderating
winds will allow for highs on Friday to reach the lower to middle
60s.

The large area of high pressure will move to the East Coast on
Saturday. Beginning late Friday night and continuing into Saturday,
a developing warm front to our southwest will push northeast.
Increased light rain chances and perhaps some elevated thunder are
possible ahead of and along this warm front late Friday night and
Saturday. Temperatures will be closer to average with highs in the
upper 60s to lower 70s.

A warming ridge of high pressure will build into the region on
Sunday. This building ridge and a light to moderate southwest flow
will allow for temperatures to soar well into the 70s to near 80 on
Sunday.

&&

.AVIATION /15Z MONDAY THROUGH FRIDAY/...
VFR conditions are expected through Tuesday. Light NW winds
expected today, becoming calm tonight. Winds will turn
southerly on Tuesday, and may gust to around 15-20 knots during
the afternoon hours.

A cold front will cross the area late Tuesday night into
Wednesday. A few light showers are possible, but prolonged sub-
VFR conditions are unlikely. WNW winds may gust to 25 kt on
Wednesday.

VFR conditions Thursday through Friday night. Winds north to
northeast 10 knots Thursday, becoming east 5 to 10 knots Thursday
night. Winds becoming southeast 10 to 15 knots Friday and Friday
night.

&&

.MARINE...
-- Changed Discussion --
Winds will diminish later this morning through tonight as high
pressure builds across the area. Southerly winds will gradually
increase Tuesday, with advisories possible by Tuesday afternoon
into the night. A cold front will cross Wednesday with a wind
shift to the WNW and become gusty. Advisories will likely be
needed Wednesday and Wednesday night.

No marine hazards expected Thursday through Friday night. Winds
north to northeast 10 to 15 knots Thursday, becoming east around 10
knots Thursday night. Winds southeast 10 to 15 knots Friday and
Friday night.
-- End Changed Discussion --

&&

.TIDES/COASTAL FLOODING...
Anomalies are just above one foot this morning and will hover
there through Tuesday. While flooding appears unlikely during
this time, sensitive locations could be close. Southerly winds
will drive an increase in anomalies Tuesday night, and this
appears the most likely time for some locations to experience
minor flooding. NW winds Wednesday will push water levels back
down.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
DC...Frost Advisory from 2 AM to 8 AM EDT Tuesday for DCZ001.
MD...Frost Advisory from 2 AM to 8 AM EDT Tuesday for MDZ003>006-
     008-011-013-014-016-503>508.
VA...Frost Advisory from 2 AM to 8 AM EDT Tuesday for VAZ028-030-
     031-036>040-050-051-053>057-501-502-505>508-526-527.
     Freeze Warning from 2 AM to 8 AM EDT Tuesday for VAZ025>027-
     029.
WV...Frost Advisory from 2 AM to 8 AM EDT Tuesday for WVZ051>053.
     Freeze Warning from 2 AM to 8 AM EDT Tuesday for WVZ050-055.
MARINE...None.
-- End Changed Discussion --

&&

$$

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