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658
FXUS61 KAKQ 180140
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
940 PM EDT Mon Jun 17 2024

.SYNOPSIS...
High pressure drifts off the New England coast through midweek.
A very warm and dry pattern then looks to take hold for much of
the week ahead. Heat peaks this weekend with highs in the upper
90s to low 100s.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
As of 940 PM EDT Monday...

Key Message:

- Dry and pleasant tonight.

Latest analysis reveals 1024mb high pressure is centered just
offshore of the New England coast, with the surface ridge axis
extending S-SW across the lower mid-Atlantic coast. Aloft,
well-advertised, and anomalously strong, upper level ridge
was centered to our west this evening. Late afternoon/early
evening convection in vicinity of the Blue Ridge has remained
west of the local area. Partly cloudy west to mostly clear east
this evening with temperatures primarily in the 70s. Remaining
partly to mostly clear overnight w/early morning lows generally
in the mid-upper 60s (highest in the Piedmont and near the coast
where some lingering mid-clouds and low-level moisture will be
more robust).
-- End Changed Discussion --

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY NIGHT/...
As of 155 PM EDT Monday...

Key Messages:

- Continued warm and dry through the midweek period as the core
  of the upper ridge lifts just north of the local area.

Surface high pressure remains anchored offshore of the mid-
Atlantic Tuesday and Wednesday, before weakening slightly as it
builds down into the Carolinas by Thu. Weak low-level onshore
flow maintains an atypical temperature pattern (warmer NW,
cooler SE) in place. Highs each day will be in the upper 80s SE
(mid 80s at near the coast) to the low 90s NW, with highs
increasing into the upper 80s to low 90s on Thu. Dewpoints will
remain in the 60s which will keep heat index values very near
the air temp. Clouds, outside of typical afternoon cumulus, will
be hard to come by with strong ridging aloft. Low temps mainly
in the 60s each night with low 70s possible along the coast.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
As of 155 PM EDT Monday...

Key Messages:

- Hot and increasingly humid conditions expected Saturday and
  Sunday.

- Remaining mainly dry through the week.

The anomalously strong upper heat ridge peaks at around ~600
dam over the northeast Friday morning. Highs inland rise into
the mid 90s for the NW half of the area on Friday with low 90s
to the SE (upper 80s near the immediate coast). Dew points look
to mix out into the 60s once again, so max heat index values
remain within 1-2 deg F of the air temperature.

Looking ahead, the main weather story this weekend remains the
persistent and increasingly oppressive heat. Sfc high pressure
slides into a more typical summertime Bermuda Ridge pattern in
the western Atlantic. This allows return flow to pull in hot
and more humid air into the region over the weekend, with PW
rebounding back toward typical climo values for late June.
EPS/GEFS probs and thickness schemes from both the ECMWF and GFS
continue to favor widespread highs in the upper 90s and Max
Heat Indices creeping into the upper 90s to low 100s on Saturday
and potentially 105+ in spots on Sunday (especially eastern
sections). Equally as important, relief at night will become
increasingly harder to come by, with overnight lows only falling
to around 70 degrees Friday night, and into the lower to middle
90s Sat and Sun nights. Therefore, while no heat-related
headlines are necessary for much of the forecast period, it is
appearing increasingly likely that we will need to ramp up heat
messaging to core partners for later this week, with some heat
headlines a good bet to be needed over at least a portion of the
area by this weekend.

Regarding rain chances, increasing PW and the likely re-emergence
of a weak lee trough by next weekend does allow for at least
a better chance of some possible showers/storms by Sunday and
Monday. Will maintain a slight to low-end chance (20-30%) during
the late afternoon and early evening.

&&

.AVIATION /02Z TUESDAY THROUGH SATURDAY/...
As of 750 PM EDT Monday...

High pressure is centered off the coast as of 00z and will
continue to prevail through the next 24 hours bringing VFR
conditions. SCT mid and high clouds inland will gradually
dissipate this evening. There is a potential for some SCT-BKN AC
with bases of 6-8kft later tonight into Tuesday morning, with
FEW-SCT CU inland during the aftn. The wind will be light out of
the SSE tonight, and then become SE ~10kt later Tuesday morning
into the aftn.

Dry and VFR conditions are expected to prevail through Saturday
as high pressure remains centered off the coast.

&&

.MARINE...
As of 250 PM EDT Monday...

Key messages:

- Small Craft Advisories remain in effect into early tonight for the
Chesapeake Bay, York River, and Rappahannock River

- Southeast winds briefly increase to 15-20 kt across the Chesapeake
Bay Tuesday afternoon into early Tuesday evening

-Winds and seas increase late Sunday into Sunday night.

Afternoon surface analysis depicts high pressure offshore with a
ridge aloft over the East Coast. This features remain in place
through the week with a repeating diurnal pattern each day with
winds generally S/SE each day. Winds this afternoon were generally
S/SE 15-20 kt with gusts to 25 kt across the Ches Bay with lower
winds across the James River, Currituck Sound, and coastal waters.
12z CAMs have increased consensus and confidence in winds increasing
to 15-20 kt with gusts to 25 kt into the Rappahannock and York
Rivers later this afternoon. As such, SCAs have been expanded to
included these rivers. While a few gusts to 20 kt are possible over
the James River and Currituck Sound late this afternoon into this
evening, confidence is too low to expand the SCAs to these areas
with most model guidance keeping winds sub-SCA. SCAs will remain in
effect until 10 PM for the upper rivers, 1 AM Tue for the lower bay,
and 4 AM Tue for the middle and upper bay. Winds become S,
diminishing to 5-10 kt late tonight. Winds become SE Tue, increasing
to 15-17 kt with gusts to 20 kt across the Ches Bay and rivers Tue
afternoon into Tue evening. Will continue to monitor for the
potential for marginal SCA conditions Tue afternoon/evening,
however, wind probs remain relatively low at this time (<25%).
Relatively benign marine conditions are expected from Tue night into
this weekend as a ridge remains over the East Coast with high
pressure offshore. Some model guidance suggests a period of elevated
seas and high period swell Sun into Mon as a potential wave of low
pressure moves towards the Southeast coast. Will continue to monitor.

Waves and seas build to 2-3 ft and 3 ft respectively later this
afternoon into this evening. Waves and seas remain 1-3 ft and 2-3 ft
through Wed. There is the potential for 3-4 ft seas Thu-Fri night.
However, seas should remain sub-SCA. Some model guidance suggests
that seas build Sun into Mon to SCA criteria (~4-6 ft) due to a wave
of low pressure moving towards the Southeast coast.

The rip risk is moderate across the N beaches (due to higher period
swell of ~11 seconds) on Tue and low across the S beaches (due to a
lower period swell of ~6 seconds) with a moderate rip risk across
all area beaches on Wed due to building seas and a more onshore flow.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 4 AM EDT Tuesday for ANZ630-631.
     Small Craft Advisory until 1 AM EDT Tuesday for ANZ632-634.
     Small Craft Advisory until 10 PM EDT this evening for ANZ635-
     636.

&&

$$

SYNOPSIS...MAM
NEAR TERM...AJZ/MAM
SHORT TERM...MAM
LONG TERM...MAM/RHR
AVIATION...AJZ
MARINE...RMM