462
FXUS61 KAKQ 281902
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
302 PM EDT Fri Jun 28 2024

.SYNOPSIS...
High pressure builds north of the region through this morning,
then slides off the southern New England coast for this
afternoon into tonight, providing dry weather. Heat and
humidity return for Saturday and Sunday, with an increased
chance of showers and thunderstorms Sunday into Sunday night.
A cold front drops across the area late Sunday night through
Monday morning.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
As of 300 PM EDT Friday...

High pressure to the N slid offshore this afternoon and is now
centered off the coast of New England. Pretty quiet today with dry
weather and scattered to broken CU across the area. Temps have risen
into the mid to upper 80s for much of the area, but breezy onshore
winds have kept coastal locations cooler. Areas along the coast are
showing the low 80s and the Eastern Shore only in the upper 70s so
far. Expect another degree or two to be added before the afternoon
is over. Cloud cover will temporarily thin out later this evening,
then build back in after midnight through sunrise. Lows tonight will
be in the upper 60s for much of the area with lower 70s in the SE
and immediately along the bay.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/...
As of 400 AM EDT Friday...

Key Messages:

- Heat rebuilds across the region Saturday with more humidity.

- Dangerous heat indices likely across parts of the area on
  Sunday as heat and humidity peak ahead of a cold front.

- Scattered to numerous thunderstorms are expected Sunday
  afternoon into Sunday night.

The sfc high pressure will be off the New England coast for
tonight into early Sat, with some moisture returning as a weak
warm front lifts through the area. Will maintain a dry fcst, but
an isolated shower could come up into NE NC by Sat morning.
Lows tonight will be mainly in the upper 60s to mid 70s. Heat
and increasing humidity return Sat, as high pressure shifts
farther out to sea resulting in low level flow becoming SSE.
This will allow 850mb temps to rise to ~20C, which supports
widespread lower to mid 90s inland/Piedmont. Highs near the
coast are expected to be in the upper 80s to near 90 (lower to
mid 80s at the MD beaches), as there will still be a bit of an
onshore component to the flow. This combined with sfc dewpoints
in the lower 70s will result in heat indices in the upper 90s to
lower 100s. There is a slight chc to low chc of aftn showers/tstms
over the Piedmont in the vicinity of a subtle lee-side trough.
Although mid to upper level height rises will act to suppress
more widespread convection despite the fact that there will be a
decent amount of sfc-based instability present.

Another upper trough and cold front will approach the area on
Sun, and that cold front will cross the area Sun evening into
Mon morning. The LLVL flow will increase out of the SW on
Sun ahead of the front, allowing 850mb temps to rise to 20-23C.
This will result in hot and humid conditions with mid 90s
expected inland/Piedmont, and 88-94 near the coast (morning
lows will be in the mid to locally upper 70s). With dew pts in
the mid 70s in most areas during peak heating, dangerous heat
indices of 105-107F are in the forecast. Note that the dew
point forecast continues to be a couple degrees lower than
NBM and is more in line with MOS values. In addition, sctd to
numerous tstms are expected area-wide from Sun aftn-Sun night
along and ahead of the cold front. Tstms will diminish from NW
to SE late Sun night. Given the heat and humidity/ample
instability, could see localized damaging wind gusts with any
storms that form (mainly during the aftn/evening). Lows Sun
night in the mid 60s to lower 70s.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 400 AM EDT Friday...

Key Message:

- A brief break in the heat is likely early next week before
  very hot weather potentially returns by Independence Day.

A slight reprieve in the heat is likely early next week in the wake
of the cold front, as the 00z/28 EPS and GEFS continue to
depict below average 850mb temperature anomalies Mon and Tue.
However, the ensemble guidance also surges the heat back into
the region by the middle of next week just prior to Independence
Day, with forecast highs well into the 90s for much of the
area. Other than a few lingering showers in NE NC Mon morning,
dry wx is expected through next Wed.

&&

.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
As of 130 PM EDT Friday...

SCT cloud cover is present across the FA this afternoon with cloud
bases around 3-4kft. Have seen a few instances of brief MVFR
with thicker patches of clouds, but otherwise VFR today. Cloud
cover will temporarily scatter out this evening, then build back
toward BKN after midnight. Guidance favors MVFR across most TAF
sites late tonight into early Sat. Cannot rule out IFR at RIC
during the early morning hours. ENE winds will continue to be
gusty along the coast through the afternoon. Winds turn to the
SE late tonight.

High pressure and mainly dry conditions will prevail for today
through at least Sat morning. Sctd showers/tstms are likely
Sun into Sun night. High pressure and drier conditions return
for Mon.

&&

.MARINE...
As of 300 PM EDT Friday...

Key messages:

- Generally sub-SCA conditions with periods of breezy
onshore/southerly winds this evening through the weekend.

- A period of SCA conditions is very likely on Monday with northerly
winds behind a cold front.

- Moderate risk of rip currents through Saturday.

The secondary cold front is south of the waters this afternoon with
high pressure centered south of Long Island. There is still a decent
pressure gradient in place, which is resulting in E-NE winds around
15 kt with gusts to 20 kt over the marine area. Winds become SE and
remain near 15 kt this evening-tonight as the high pushes offshore
before becoming SSE on Saturday. Could see a period of low-end SCA
conditions on the bay late Sat evening-Sat night as the winds become
more southerly and increase to 15-20 kt. Local wind probs show a 40-
70% chc of sustained 18 kt winds between 8 PM Sat-4AM Sun (highest
on the mid/upper bay). Winds diminish to 10-15 kt and become SSW by
mid to late Sun AM.

A decently strong summer cold front looks to approach the area
Sunday before crossing the waters from N-S between 4-10 AM Monday
morning. Scattered to numerous tstms are expected Sun aftn through
the first part of Sun night, which will likely necessitate SMWs (a
few of the storms could even produce 50 kt wind gusts). Sub-SCA
outside of any storms from Sun-late Sun evening. However, there will
be decent cool/dry advection following the cold FROPA Monday
morning, which will allow N winds to increase to ~20 kt (with
frequent gusts around or just above 25 kt). SCAs will likely be
needed for all of the Ches Bay, Lower James, and maybe even the
upper rivers/coastal waters. Local wind probs show nearly a 100% chc
of sustained 18 kt winds Mon AM, with low (~20%) probs of sustained
25 kt winds.

Waves/seas 1-3 ft/2-4 ft this afternoon. Seas generally 3-4 ft this
weekend with 1-3 ft waves. Seas could build to 5 ft S of Cape
Charles on Monday following the cold FROPA (with 3-4 ft waves). Sub-
SCA waves and seas are expected from Mon night through the middle of
next week.

There is a moderate risk of rip currents across all Atlantic- coast
beaches in the FA through Saturday.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.

&&

$$

SYNOPSIS...TMG
NEAR TERM...AM
SHORT TERM...ERI/TMG
LONG TERM...ERI/TMG
AVIATION...AM
MARINE...ERI