Area Forecast Discussion
Issued by NWS Sterling, VA

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506
FXUS61 KLWX 010119
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
919 PM EDT Fri May 31 2024

.SYNOPSIS...
High pressure will build across the area overnight and Saturday
before sliding offshore Sunday. Dry conditions and below normal
temperatures will continue as a result into the start of the
weekend. Temperatures start to warm with increasing shower and
thunderstorm chances Sunday into the middle part of next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
A large Canadian area of high pressure will build into the
region overnight. Comfortable humidity will be ushered in on a
light northwest flow. Temperatures will be cooler than average
with lows in the middle to upper 40s mainly along and west of
the Blue Ridge and low to mid 50s further east.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
Previous discussion...
Low humidity and dry conditions will continue into the start of
the weekend as high pressure pushes toward the Mid-Atlantic
coast. The high eventually heads offshore Saturday night into
Sunday as a weak area of low pressure approaches from the Ohio
River Valley. This will allow for increasing clouds across the
area along with renewed chances for scattered showers and
thunderstorms mainly west of the Blue Ridge Sunday late morning
and into the evening hours.

High temperatures Saturday will be a touch warmer in the upper 70s
and lower 80s. Winds will turn to the south while remaining light as
high pressure pushes towards the coast. Skies will remain mostly
sunny with just some high cirrus floating through. Low level
moisture increases Saturday night into Sunday morning leading to
added cloud cover and perhaps a few showers west of the Allegheny
Front as weak low pressure pushes east from the Ohio River Valley.
Lows Saturday night will fall back into the mid 50s to low 60s for
most of the area outside the mountains.

By Sunday, upper level ridging begins to flatten with high pressure
just offshore. Zonal flow will develop aloft allowing for the
progression of several shortwave disturbances eastward into the
region. This will lead to isolated to scattered showers and
thunderstorms mainly west of the Blue Ridge early in the day
before spreading east toward the metros late in the afternoon.
Storms should be sub-severe although some gusty winds and hail
cannot be ruled out. Winds will will switch to the southwest
with gusts up to 20 mph ushering in warmer temperatures in the
upper 70s and low to mid 80s. Humidity will also increase as
well. Any convection will wane after sunset Sunday with quieter
conditions expected due to upper level ridging nearby. Lows
Sunday night will fall back into the upper 50s and low to mid
60s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
A closed upper low will be exiting the area Monday afternoon
with upper ridging forecast to build in during the middle
portion of next week. Dry conditions are expected Monday and
Tuesday. A large cyclonic circulation over south central Canada
will dive southeastward toward the Great Lakes during the
second half of next week pushing a cold front into the area
during the Thu-Thu night frame. Expect an increase in shower and
thunderstorms Wednesday into Thursday. Shear and instability do
not look particularly strong enough at this time to support a
significant severe wx threat.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
VFR conditions are expected through Saturday. Winds will become
light and variable Saturday morning before switching to the
south Saturday afternoon and at night as high pressure
gradually pushes offshore. Skies will remain mostly sunny to
clear with high cirrus likely returning to western terminals
Saturday afternoon. More widespread mid and high level cloud
cover returns late Saturday night into Sunday morning. Even with
that said, VFR conditions should prevail.

VFR conditions are expected Sunday with high pressure just offshore.
A slight chance for a few thunderstorms is possible mainly at
terminals along and west of a line from KMRB down to KCHO. Some
restrictions are possible in and around any thunderstorm activity
that may form. Prevailing VFR conditions are expected on both
Monday and Tuesday. Winds will be light out of the north to
northwest on Monday, and light out of the southeast on Tuesday.

Higher chances for more widespread restrictions from
shower and thunderstorm activity are possible during the afternoon
and evening hours Wednesday through Thursday as multiple pieces
of shortwave energy push through. Highest chances for
thunderstorms will be at terminals west of a line from
KHGR/KMRB/KIAD/KDCA south toward KCHO and KLYH.

&&

.MARINE...
Wind will diminish overnight to sub-SCA conditions. Sub- SCA
level winds are expected through early Sunday morning as high
pressure remains nearby. Winds will become light and variable
tonight before switching to the south Saturday afternoon.

Sub-SCA level winds are expected Sunday into Monday. South to
southeasterly winds return Sunday as high pressure pushes off the
southeast U.S coast. An isolated shower or thunderstorm cannot be
ruled out due to the bay breeze Sunday afternoon/evening. Better
chances for showers and thunderstorms exists Monday through
Wednesday as multiple disturbances pass through. Cannot completely
rule out the need for a Special Marine Warning for any strong storms
that cross the waters during that period.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
DC...None.
MD...None.
VA...None.
WV...None.
MARINE...None.

&&

$$

SYNOPSIS...EST
NEAR TERM...KLW/EST
SHORT TERM...EST
LONG TERM...LFR
AVIATION...LFR/KLW
MARINE...LFR/KLW