Area Forecast Discussion
Issued by NWS Sterling, VA

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347
FXUS61 KLWX 051852
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
252 PM EDT Sun May 5 2024

.SYNOPSIS...
An active pattern will continue through mid-week as multiple
disturbances pass through the area. A cold front will move through
toward the end of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A turn in wind direction out of the south and southwest in the
Appalachians and Shenandoah Valley may be indicating that the
CAD wedge maybe gradually eroding away. Light rain showers exist
on radar from northeastern Maryland, southwest to just east of
Washington D.C. to near Fredericksburg, VA. Additional popup
showers are developing over western Maryland and parts of
north-central West Virginia. These showers may be accompanied by
thunderstorms as the afternoon progresses into this evening.
Temperatures have only managed to climb a few degrees in the CAD
wedge to the east of the Blue Ridge, while temperatures to the
west of the CAD wedge have risen an average of 5 to 8 degrees in
the past 2 to 3 hours. Highs under the CAD wedge will be in the
lower to middle 60s, while highs where there was some sunshine
this morning will reach the lower to middle 70s.

Drier conditions will evolve tonight but skies could still
remain cloudy for most. Patchy fog may form in parts of the VA
Piedmont and northern and northeastern VA where clouds break.
Visibility may drop to a mile or two. Tonight`s lows will not be
as cool as last night with lows in the upper 50s to mid 60s.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
A mid-level low pressure system over the western Ohio Valley
will send waves of energy east into our region Monday, Monday
night and into Tuesday. This will provide a prolonged period of
cloud cover, developing showers and a couple of thunderstorms,
and perhaps some erratic wind directions and speeds, depending
on where any stationary fronts or cold fronts align during this
36 hours period early in the week. Highs Monday will be warmer
with highs in the upper 70s and lower 80s. Showers and
thunderstorms appear possible Monday afternoon, with the
greatest coverage expected to be across the Central Shenandoah
Valley into Central Virginia, where low- level convergence is
expected to be maximized. Showers and thunderstorms could be
slow-moving Monday into Monday evening; thus, heavy rainfall
could bring a chance for some isolated flooding. Rain amounts
could be on the order of a few inches.

Additional showers and thunderstorms appear possible again on
Tuesday as a disturbance tracks into the Great Lakes. Much like
Monday, high temperatures are expected to reach into the upper
70s and lower 80s. Soundings again show relatively saturated
profiles along with some surface based instability, so storms
may once again be heavy rainfall producers.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Rain and thunderstorm chances will continue by Wednesday, with
an approaching cold front from the west. The precip chances will
increase from west to east later in the day on Wednesday with
highs in the mid to upper 80s for the lower elevations and 70s
for the mountains. Winds out of the west will be gusting to 15
to 20 knots throughout the afternoon. Precipitation chances
increase overnight Wednesday and through the day on Thursday as
the front continues to approach the area. Given the increasing
instability ahead of the front, a few isolated strong to severe
thunderstorms may be possible with the frontal passage on
Thursday. Additionally, some isolated instances of flooding will
be possible with the continuous prolonged batches of
precipitation over just a few days. Still a lot of uncertainty
pertaining to timing, intensity and antecedent conditions. Highs
on Thursday will climb into the upper 70s to low 80s for most
areas.

Behind the front on Friday, precipitation will likely linger around
with highs in the 70s for the lower elevations and 60s in the
mountains. Northwest winds will remain elevated with gusts getting
into the 15 to 25 knots range, with the higher amounts along the
higher elevations. Lingering light showers may persist into the
weekend with highs in the mid to upper 60s for most areas with 50s
in the mountains.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
IFR conditions with rain showers will linger at the major
terminals along I-95 and northeast Virginia for another few
hours this afternoon. Additional showers or thunderstorms could
move across MRB, IAD later this afternoon as they develop and
move east. Winds will become more southeast to southerly late
into this evening. IFR ceilings and fog look to build back in
tonight.

VFR conditions is expected on Monday. An afternoon or evening
shower or thunderstorm may be possible at any of the terminals,
with CHO standing the greatest chance to see impacts. Winds will
be light and somewhat variable Monday. Prevailing VFR
conditions continue into Tuesday, with afternoon showers and
thunderstorms possible once again. Winds will turn southerly on
Tuesday, but remain relatively light.

Mainly VFR conditions for the terminals on Wednesday with increasing
chances of sub-VFR ceilings by Wednesday night into Thursday as
precipitation begins to track across the area. Winds out of the west
will continue to gust out of the west.

&&

.MARINE...
Winds will become southeast to southerly. SCAs remain in effect
for the wider waters this afternoon. SCAs may potentially need
to be extended a bit into the overnight hours in channeled
southerly flow. Thereafter, sub-SCA magnitude is expected on
both Monday and Tuesday. Thunderstorms will be possible both
Monday and Tuesday. Any storms that move over the waters could
lead to the issuance of SMWs.

SCA conditions are possible Wednesday and Thursday with increasing
pressure gradient over the waters. Additionally, an SMW may be
needed for any stronger thunderstorms that cross the waters Thursday
afternoon and evening.

&&

.TIDES/COASTAL FLOODING...
More sensitive sites will encounter minor to possibly moderate
coastal flooding through Monday morning. Winds will begin to
turn more out of the southwest on Monday with slow improvements
in coastal flooding through midweek. Additional periods of
coastal flooding are possible into Wednesday.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...Coastal Flood Advisory until 9 PM EDT this evening for DCZ001.
MD...Coastal Flood Advisory until 5 PM EDT this afternoon for
     MDZ014.
VA...None.
WV...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ533-
     534-537-543.

&&

$$

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