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611
FXUS61 KLWX 061359
AFDLWX

Area Forecast Discussion
National Weather Service Baltimore MD/Washington DC
959 AM EDT Thu Jun 6 2024

.SYNOPSIS...
Unsettled weather continues through this evening as a cold front
moves across the area. Dry conditions Friday into Saturday as high
pressure builds over the region. A slow moving upper trough
approaches the area from the Great Lakes Saturday night into Sunday,
leading to more unsettled conditions.

&&

.NEAR TERM /THROUGH TONIGHT/...
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No major changes to the previous forecast. Have worked with SPC
to see if a Slight Risk is warranted for portions of the area
east of I-95. Will continue to evaluate the 12Z guidance to
collaborate any risk updates with the 1630Z outlook. Previous
discussion follows...

A cold front currently over the OH valley will move across our area
today, bringing another round of showers and thunderstorms. The
early morning showers and few embedded storms in WV and western PA
will move into the Alleghenies by sunrise. Not expecting any strong
storms, though some locally heavy rainfall is possible.

The potential for strong to severe thunderstorms is going to focus
along and east of the Blue Ridge this afternoon, though a few strong
storms could also develop in the Central Shenandoah Valley. Morning
cloud cover is expected to quickly dissipate, allowing for good
diurnal heating and destabilization to take place. Temps this
afternoon reach the mid to upper 80s, with dew points still in the
lower 70s. The atmosphere remains very moist as PWATs hover around
2.0" through the afternoon.

Most of the high res models indicate a broken line of thunderstorms
developing along the front as it reaches I-81, but especially as it
moves east of the Blue Ridge where the better instability will be.
Deep layer shear around 20-30 knots should be enough to allow some
organized strong to severe convection to get going. SPC currently
has a Marginal Risk (level 1 of 5) for severe storms, though that
could be upgraded to a Slight Risk (level 2 of 5) for areas east of
the Blue Ridge later this morning. Damaging wind gusts will be the
main threat from storms. Faster storm motion should prevent any
significant flooding issues from occurring, though there will be
quick downpours in the stronger storms.

The front and line of storms push east of I-95 by sunset, then any
lingering showers behind the front dissipate by late evening. Dry
conditions overnight as lows settle in the mid to upper 50s
along/west of I-81 and low to mid 60s to the east.
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&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
Dry conditions expected Friday and Saturday as large surface high
pressure moves across the region. A large upper trough remains
enough to our north through Saturday afternoon, but starts to dip
south closer to our area Saturday night. This could bring a few
showers to the Alleghenies for the second half of the weekend.

Afternoon highs will be in the upper 70s to mid 80s each day, with
overnight lows in the upper 50s to mid 60s.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
An upper level trough is expected to remain over the area for the
duration of the extended with the main feature of interest being a
strong cut-off low descending into the Northeast. Guidance has come
into better agreement in recent runs, consistently taking the upper
low towards Maine with a shortwave digging into the Mid-Atlantic
behind it with an associated cold front. The system has trended
drier overall, the front starved of moisture as it swings through
the area on Sunday. Sunday still has the best chance for precip of
the extended, with PoPs 30-40%. The focus of diurnal shower and t-
storm activity remains the northwestern portions of the CWA to
start, before extending southeast across the area through the
afternoon.

Some lingering showers are possible on Monday along the Alleghenies.
Tuesday currently looks drier, but there is some uncertainty
regarding a shortwave diving south into the region behind the
primary upper low as it departs. Some guidance keeps it to our east
with weak upper level ridging building in over us behind it, but
solutions that bring the shortwave to us could bring a few showers.
The air mass in the wake of the cold front appears fairly dry
though, so currently appears there won`t be much moisture to act on.

Highs in the upper 70s to mid 80s on Sunday cool into the low 70s to
low 80s behind the cold front on Monday, then gradually warm through
the week. Lows will generally be in the 50s to low 60s.

&&

.AVIATION /14Z THURSDAY THROUGH MONDAY/...
A cold front will slowly move across the area today, bringing
another round of showers and thunderstorms to most terminals this
afternoon. Ahead of the front, early morning showers are likely at
MRB. Some low clouds causing MVFR CIGs are possible this morning,
though confidence is low in widespread low stratus.

Any strong thunderstorm this afternoon could produce wind gusts in
excess of 35 knots. TEMPO groups will likely be added to the TAFs in
later updates as confidence increases for thunderstorm impacts.

Dry conditions this evening behind the cold front as southerly winds
shift to the west. After that, VFR conditions are expected through
Saturday as high pressure builds in from the west.

Predominantly VFR conditions are expected Sunday into early next
week but showers and thunderstorms in the afternoon/evening could
bring restrictions to the terminals. The late weekend system has
been trending drier overall, so the potential for this appears to be
decreasing. MRB and CHO are the most likely to see precip Sunday. NW
winds could gust 15-20 kts on Sunday. Showers could linger into
Monday but likely stay west of all terminals.

&&

.MARINE...
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A Small Craft Advisory continues through this evening for all
the waters.

Southwest to west winds this afternoon around 10 knots. A slow
moving cold front will cross the waters late afternoon into the
evening. A line of showers and thunderstorms will accompany the
front. Special Marine Warnings are likely needed for strong storms
capable of producing wind gusts in excess of 35 knots.

High pressure builds into the region from the west Friday into
Saturday. West winds are likely to remain below SCA criteria.

Westerly winds on Sunday turn northwest behind a cold front. Winds
over the waters are expected to stay below SCA criteria. Showers and
thunderstorms on Sunday could bring stronger gusts to the waters in
the afternoon.
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&&

.TIDES/COASTAL FLOODING...
With a steady southerly flow in place across the region, tidal
anomalies have been on the increase. Elevated water levels will
continue through this morning`s high tide cycle, where Annapolis
could even approach Moderate flood stage. A cold front crosses the
area early today, with the resulting west winds causing tidal
anomalies to drop by this evening/tonight.

&&

.LWX WATCHES/WARNINGS/ADVISORIES...
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DC...Coastal Flood Advisory until 11 AM EDT this morning for DCZ001.
MD...Coastal Flood Advisory until 1 PM EDT this afternoon for
     MDZ508.
VA...None.
WV...None.
MARINE...Small Craft Advisory until noon EDT today for ANZ530>533-
     537>541.
     Small Craft Advisory until 2 PM EDT this afternoon for ANZ534-
     543.
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&&

$$

SYNOPSIS...KRR
NEAR TERM...CPB/KRR
SHORT TERM...CPB/KRR
LONG TERM...CAS
AVIATION...CAS/KRR
MARINE...CAS/KRR
TIDES/COASTAL FLOODING...LWX