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602
FXUS61 KAKQ 262338
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
738 PM EDT Sun May 26 2024

.SYNOPSIS...
A cold front approaches the area into Monday. Additional rounds
of showers and storms are possible this afternoon and especially
Monday, with potential severe weather as well for Monday. An
upper trough brings cooler and comfortable weather to end the
week.

&&

.NEAR TERM /UNTIL 7 AM MONDAY MORNING/...
-- Changed Discussion --
As of 735 PM EDT Sunday...

Key Messages:

- Severe Thunderstorm Watch in effect for the Piedmont until 11 PM.
  Main threat is damaging wind gusts as a line of thunderstorms
  approaches from the west.

- That line of storms is expected to weaken as it pushes toward I-
  95 and especially points east.

- A weakening complex of thunderstorms will approach late
  tonight, but likely remains just to our west through sunrise.

Scattered strong to severe storms that formed along a sea breeze
boundary have dissipated. However, we are now watching a line
of storms that is currently over western VA but steadily moving
E/NE. There is still some uncertainty with respect to how
intense it will be when it arrives (likely by 9 PM in our far
western counties)...as instability wanes with the loss of
daytime heating and shear is still weak. In coordination with
SPC, still have enough confidence to issue a Severe Tstm Watch
(main threat is damaging wind gusts) for our Piedmont counties
until 11 PM. May need to expand this to near I-95 if it looks
like the line will hold together long enough. The line will
weaken as it approaches I-95 and especially points east as these
areas saw convection earlier today.

Late tonight, a weakening MCS should move toward the area from
the W, but will likely just be west of our CWA border by
sunrise. Overnight lows in the in the mid-upper 60s.
-- End Changed Discussion --

&&

.SHORT TERM /7 AM MONDAY MORNING THROUGH WEDNESDAY/...
As of 240 PM EDT Sunday...

Key Messages:

- There is a threat of severe weather for Memorial Day (Monday).
Damaging winds, large hail, and a few tornadoes are possible.

- Quieter Tuesday, with scattered showers and isolated storms across
the north Wednesday.

****Severe weather expected Monday with all modes of severe
possible. Those with outdoor Memorial Day plans should closely
monitor the weather for warnings as multiple rounds of strong to
severe storms could occur.****

The setup for Monday is complicated and heavily dependent on the
behavior of early-day convection. The broad weather pattern will be
characterized by an approaching mid-level shortwave and increasing
flow aloft. Several subtle impulses will slide eastward through the
area during the day, with one expected to cross the area in the mid
to late morning. This is before the brunt of daytime heating occurs
in the afternoon. Several experimental CAMs show a line of
convection crossing the area in the late morning, around 15z or so.
This could pose a threat of isolated wind damage, heavy rain, and
lightning. The impact of this activity on afternoon redevelopment is
the main question. While there could be a good degree of
stabilization from this early convection, most guidance insists of
robust airmass recovery with MLCAPE building to 1500+ J/kg in in the
afternoon. A few models even show values of 2000-3000 J/kg, which
would support extremely strong updrafts. Effective shear values will
be very supportive for severe weather with 35-50 kts across most of
the area. Therefore, afternoon redevelopment seems like a good bet
and all modes of severe will be possible. The large hail threat is
supported by mid-level lapse rates of 7-8 C/km, highest across the S
and SE. With southerly surface winds and SW winds aloft, there is
also some directional shear supportive of a non-zero tornado threat.
Forecast soundings show 150-200 m2/s2 of 0-1km SRH and favorably
curved hodographs, again highest across the S/SE. Changes to the day
2 SPC include an expansion of the slight risk to the entire area and
the introduction of a 5% tornado threat for most of our CWA. PoP-
wise, did trend PoPs down a bit mainly due to questions regarding
coverage. However, the severe potential remains unchanged. Highs
will be very warm to hot and in the upper 80s-low 90s (low 80s
immediate coast). Outside of storms, skies stay mostly or partly
sunny. Storms may linger across the SE into the overnight Monday.

Much quieter Tuesday with a lingering shower or storm across the far
SE. Highs in the low-mid 80s under a mostly sunny sky. Upper
troughing situates over the eastern CONUS for the middle of the
week. On Wednesday, a potent shortwave will dive SE and move through
nrn portions of the area. This is expected to bring an increase in
cloud cover and isolated to scattered showers, mainly N and E of the
I-64 corridor and especially on the MD Eastern Shore. Cooler temps
aloft will allow for the development of some modest CAPE in the
afternoon, so cannot rule out a few rumbles of thunder as well.
Highs will be in the upper 70s/around 80F N/NW to the low-mid 80s
S/SE. Cooler Wed night w/ lows in the 50s for most of the area and
lower 60s for the far SE.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
As of 240 PM EDT Sunday...

Key Message:

- Cooler and more comfortable to end the next week.

Another shortwave within the larger longwave trough pivots toward
the area later Thursday into Friday. However, drier air will work
against any precip chances. Still could see increases in cloud cover
in the aftn during peak heating, however. With the drier air and
lower heights aloft, temps will trend back into the 70s with dew
points in the 40s and 50s. Thus, it will feel much more comfortable.
High pressure builds down from the Great Lakes to end the week and
start the weekend favoring a continuation of the dry and comfortable
wx. High temps should begin to inch up some as ridging begins to
build across the eastern CONUS. Overnight lows through the extended
will be in the 50s to around 60F at the immediate coast. A few upper
40s are possible Thu and Fri night across the far NW.

&&

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
As of 735 PM EDT Sunday...

VFR at all terminals at this hour as scattered storms have
dissipated. CIGs should mainly be VFR through the period except
at SBY where a period of IFR/LIFR is possible from 02-14z.
Elsewhere, some short-lived MVFR CIGs are possible Monday AM.
Am watching a line of tstms over wrn VA that is steadily moving
E/NE. This line will continue to approach from the W late this
evening into tonight. Most guidance agrees that this should be
weakening, but cannot rule out gusty winds, heavy rain, and
lightning (best chance at RIC in the 02-05z timeframe).
Additional showers and storms may enter the area Monday morning,
but confidence in this is low to moderate. Mainly light winds
tonight, with gusty south winds (to 20 kt) expected on Monday. A
higher coverage of showers and storms (some of which could be
severe) is expected Mon aftn through Mon evening at all
terminals. Outside of storms, expect mainly VFR conditions
Mon/Mon evening.

Outlook: VFR/dry conditions expected Tue and Wed.
-- End Changed Discussion --

&&

.MARINE...
As of 200 PM EDT Sunday...

Key messages:

- Chances for showers and storms through this evening and again
tomorrow.

- Small Craft Advisory conditions possible tomorrow afternoon into
tomorrow night across the Chesapeake Bay and coastal waters due to
increasing winds and building seas.

Bermuda high pressure remains in place offshore this afternoon, with
a weak lee trough just inland. Winds are generally out of the E-SE
around 10-15 kt, with the highest winds generally concentrated in
the lower and middle bay. Visibilities continue to improve, but
there is some lingering fog near the mouth of the Chesapeake Bay and
just off the Virginia Beach coast.

Similar conditions tonight and early Monday. A cold front approaches
the area on Monday, associated with a deepening low pressure center
over the Great Lakes. Tightening pressure gradient will allow S-SW
winds to increase out ahead of the front. Winds briefly approach SCA
criteria Monday afternoon and evening in the lower Bay and coastal
waters, with E-SE wind wave potentially pushing some 5 footers
across northern and central coastal zones Monday night. Some Marine
Warnings may also be needed as strong to severe storms could
potentially cross the region tomorrow night.

The front will slow down or stall over the waters Monday night
before getting pushed through Tuesday morning/afternoon. Winds veer
around to the NW behind the front on Tuesday into midweek. A second,
reinforcing shot of cooler and drier air could bring another period
of stronger northerly winds late Wednesday night into Thursday.

Low Rip Risk on area beaches today, with a moderate rip risk for
northern beaches on Monday with building seas and more of a shore
normal component to wave energy.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Coastal Flood Advisory from 3 AM to 7 AM EDT Monday for MDZ021.
NC...None.
VA...None.
MARINE...Dense Fog Advisory until midnight EDT tonight for ANZ650.
-- End Changed Discussion --

&&

$$

SYNOPSIS...SW/TMG
NEAR TERM...ERI/SW
SHORT TERM...SW
LONG TERM...SW
AVIATION...ERI/SW
MARINE...AJB/MAM