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200
FXUS61 KAKQ 260748
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
348 AM EDT Wed Jun 26 2024

.SYNOPSIS...
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High pressure slides farther offshore today. A cold front
approaches the area later this afternoon and crosses the region
tonight into Thursday, bringing the a chance for showers and
thunderstorms. High pressure builds north of the region for the
latter portion of the week.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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As of 345 AM EDT Wednesday...

Key Message:

- Heat builds again today and heat indices likely exceed 100F
  again.

- Scattered showers and thunderstorms develop late this
  afternoon into Wednesday night, with a few storms potentially
  being strong or severe with damaging wind gusts to primary
  threat.

GOES water vapor channels depict an upper ridge over the
central CONUS with quasi-zonal flow from the Ohio Valley to the
Northeast at the base of a broad trough over the northern Great
Lakes. At the surface, high pressure is centered off the
Carolina coast and prevails locally. Mostly clear early this
morning with temperatures in the 70s and a SSW wind of 5-10 mph.
The trough over the Great Lakes will dig SE today into this
evening pushing a cold front into the Ohio Valley. The low-level
flow increases out of the SW today, allowing 850mb temperatures
to surge to 20-22C ahead of the cold front. This supports high
temperatures in the mid 90s to near 100F. Dewpoints should mix
out during the day and drop into the mid to upper 60s (perhaps
even a degree or two lower) during peak heating. So while
temperatures will be near 100F, heat indices will generally
range from 100-104F. Mostly sunny through mid-afternoon and then
becoming partly sunny with a SW wind of 10-15 mph.

Forecast soundings show that the boundary layer remains capped
much of the day prior to some height falls arriving later this
afternoon into tonight. 00z/26 CAMs continue to develop
scattered tstms in the higher elevations of W/NW VA by 3-4 PM
before trying to push SE into NW portions of the FA. The highest
tstm chances will be from 5 PM-1 AM mainly north of I-64 as the
actual front nears the area before the convection gradually
weakens early Thursday morning. Locations south of a Farmville-
Richmond-Williamsburg line will likely see little to no rain
through Thursday morning, with localized totals in excess of 1"
possible from Louisa County to the MD Eastern Shore. In
addition, any storm will be capable of producing damaging wind
gusts given very strong sfc heating, a deep well mixed boundary
layer, and some mid-level drying. In fact, forecast soundings
from most models show DCAPE values of 1200-1500 J/kg Wed
aftn/evening. The Day 1 convective outlook from SPC is very
similar with only a slight nudge southward of the slight and
marginal risk areas. Convection diminishes in coverage
overnight. However, some convection will linger overnight with
some instability and the front settling over the area. Lows
tonight will mainly be in the upper 60s to mid 70s.
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&&

.SHORT TERM /THURSDAY THROUGH FRIDAY/...
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As of 345 AM EDT Wednesday...

Key Messages:

- A few thunderstorms are possible across SE VA/NE NC Thursday
afternoon-evening.

The cold front slowly pushes south across southern VA and NE NC
Thursday as high pressure and a drier airmass build into the
northern tier of the area. Showers/tstms are expected to
redevelop along the boundary Thursday afternoon with the highest
chc across SE VA and NE NC. High temperatures return to
seasonally hot levels ranging from the mid 80s to near 90F.
Shower/tstms largely dissipate or move to our south by late
Thursday evening, although some isolated activity could linger
into the early overnight hours over southern VA. High pressure
builds across New England Thursday night into Friday following
the frontal passage. Lows Thursday night fall into the mid
60s-lower 70s. Easterly flow Friday will keep highs in the lower
to mid 80s along the coast, and seasonally hot inland with
highs in the upper 80s to around 90F.
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&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
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As of 345 AM EDT Wednesday...

Key Messages:

- Heat rebuilds across the region Saturday and Sunday and
potentially more humid.

- Scattered showers and thunderstorms are possible later Sunday
  afternoon into Sunday night ahead of a cold front.

Surface high pressure initially settles off the coast Friday
night into early Saturday, with some moisture returning as a
weak warm front lifts through the area. Therefore, there is a
slight chc to low chc of showers and perhaps a tstm from central
VA and the Piedmont to the MD Eastern Shore Friday night into
early Saturday morning. Lows Friday night are mainly in the
upper 60s to mid 70s. Otherwise, the heat builds back over the
local area this weekend as high pressure settles off the
Southeast coast. Another upper trough and cold front approach
the area from the NW late this weekend, and the cold front is
progged to cross the area Sunday night. Forecast high
temperatures are mainly in the mid 90s on both Saturday and
Sunday, with aftn dewpoints in the lower to mid 70s (mid 70s
mainly toward the coast) during peak heating on both days. This
is supported by the deterministic guidance and MOS guidance, but
is below the mid/upper 70s shown by the NBM (which is likely
too high especially given how dry it has been). Resultant heat
indices are in the upper 90s to lower 100s Saturday, and then
potentially 105-109F for much of the CWA Sunday. Isolated to
widely scattered tstms are possible on Saturday afternoon
(mainly W of I-95), with a better chc of showers/tstms later
Sunday afternoon into Sunday night as the cold front drops
through the region. A slight reprieve in the heat is possible
early next week in the wake of the cold front as the 00z/26 EPS
and GEFS each depict below average 850mb temperature anomalies
Monday and Tuesday. However, the ensemble guidance also surges
the heat back into the region by the middle of next week just
prior to Independence Day.
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&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
As of 200 PM EDT Wednesday...

High pressure is centered off the Carolina coast as of 06z. VFR
under some this cirrus with a S to SSW wind of 5-10kt. VFR today
with SCT aftn CU with bases of 5-7kft. The wind will be SSW of
8-12kt with occasional gusts to ~20kt. A cold front approaches
from the NW later this afternoon and drops into the region
tonight. There is a 40-60% chc of late aftn/evening
showers/tstms for RIC and SBY, with a 15-30% chc of
showers/tstms and ORF, PHF, and ECG tonight. A few tstms could
produce strong wind gusts along with brief flight restrictions
in heavy rain. Overall coverage of showers/tstms diminishes
after midnight.

This front will be slow to push through southern VA and NC NE
Thursday with a 30-50% chc of redeveloping aftn/early evening
showers/tstms. High pressure and dry conditions return Friday
into Saturday. A chance for showers/tstms again later Sunday.

&&

.MARINE...
As of 955 PM EDT Tuesday...

Key Messages:

- SCAs conditions expected across the Chesapeake Bay tonight.

High pressure slides off the coast and out to sea tonight into
Wed. S winds of 15-20 kt with gusts up to 25 kt (potentially up
to 30 kt across the upper bay) continue early tonight across the
Ches Bay before winds become SW 10-15 kt late tonight. As such,
SCAs are in effect for the Ches Bay. Winds average a bit lower
across the rivers with occasional gusts to 20 kt. Therefore,
have kept the rivers out of the SCAs. Seas build to 3-4 ft N
tonight into Wed, and waves in the Bay ~2ft with increasing
southerly flow. 4-5 ft seas will be possible for a brief period
north of Parramore Island late Wed aftn and evening. Another
weakening cold front pushes through the region during Thu. The
wind shifts to NE then E or SE late week and is expected to be
at or below 15kt.

Low rip current risk is forecast for all beaches today. A low rip
risk is expected again on Wed given southerly flow and short
wave periods at or below 5 secs.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 7 AM EDT this morning for ANZ630-
     631.

&&

$$

SYNOPSIS...AJZ/ERI
NEAR TERM...AJZ/ERI
SHORT TERM...AJZ/ERI
LONG TERM...AJZ/ERI
AVIATION...AJZ
MARINE...JDM/RMM/TMG