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002
FXUS61 KAKQ 221936
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
336 PM EDT Sun Sep 22 2024

.SYNOPSIS...
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High pressure builds south along the Mid-Atlantic coast early
this week. Meanwhile, a series of shortwave troughs will slide
across the region in northwest flow aloft bringing on and off
rain chances. Seasonal temperatures are expected to start this
week.
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&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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As of 330 PM EDT Sunday...

Key Message:

- Partial clearing this evening with a potential for stratus and
  patchy fog over the Piedmont later tonight.

Surface high pressure is centered over Atlantic Canada this
afternoon and is ridging SW along the Mid-Atlantic coast.
Meanwhile, low pressure lingers offshore. A backdoor cold front
has pushed SE through the area. Aloft, a trough/upper low is
offshore with a building ridge over the Ohio Valley. Mostly
cloudy to overcast in easterly flow behind the backdoor front
with temperatures in the lower to mid 70s. Mainly dry, although
a slight chc of light showers/sprinkles will linger in vicinity
of the I-95 corridor through late afternoon. Some clearing is
expected along the coast this evening and overnight. Brief
partial clearing is possible farther inland later this evening
into the early overnight hours. However, stratus and some patchy
fog are expected to develop later tonight into early Monday
morning. Forecast lows tonight are mainly in the upper 50s to
lower 60s.
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&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
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As of 330 PM EDT Sunday...

Key Messages:

- Pleasant start to the week with dry weather and highs in the
  70s.

- Low end chances for showers Monday night into Tuesday and
  again Wednesday.

Low pressure slides SE well off and farther away from the coast
Monday into Tuesday as the upper ridge builds SE into the
Southeast CONUS. Surface high pressure centered well NE of the
region will continue to build SW along the coast. Mainly dry
Monday, although a shortwave trough will bring a chc of showers
Monday night into Tuesday, and a slight chc of tstms Monday
evening and Tuesday afternoon and evening over the Piedmont.
High pressure at the coast will generally confine rain chances
to the western half of the area. The upper ridge amplifies off
the Southeast coast Wednesday. However, our western and northern
counties will still be close enough to the northern periphery
of the ridge for a chc of showers (and a slight chc of tstms) to
continue. There will be a considerable amount of cloud cover
Monday through Wednesday, especially NW. Highs Monday will
mainly be in the mid to upper 70s. Thicker cloud cover has the
potential to keep the NW counties in the upper 60s to around 70F
Tuesday, with lower to mid 70s elsewhere. By Wednesday, highs
push into the mid 70s NW to the lower 80s SE as the upper ridge
amplifies. Lows will mainly be in the 60s Monday through
Wednesday mornings.
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&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
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As of 330 PM EDT Sunday...

Key Messages:

- Multiple low-end chances for precip late next week into early
  next weekend with low confidence in regard to the eventual
  evolution of a tropical system in the Gulf of Mexico.

There is an increasing chc of tropical development in the NW
Caribbean and Gulf of Mexico Monday through Wednesday. However,
there is low confidence on how the potential system and mid-
latitude jet interact by late week into next weekend. The
general trend amongst the 12z/22 models is for the tropical low
to move into the mid-South while an upper low dives SE off the
New England coast, and high pressure nudges into the northern
Mid-Atlantic. This would generally keep much of the moisture SW
of the area, with some rain trying to nudge in from the SW
Friday into Saturday. At this time, PoPs are generally at or
below 20% for the late week into next weekend (highest SW albeit
still low), with seasonal high temperatures in the mid 70s to
around 80F and lows in the upper 50s to mid 60s.
-- End Changed Discussion --

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
As of 200 PM EDT Sunday...

High pressure continues to be centered over Atlantic Canada as
of 18z and is ridging SW along the Mid-Atlantic coast.
Meanwhile, a backdoor cold front has pushed through the area.
Cigs are primarily MVFR with an ENE wind of 5-10kt. Cigs are
expected to slowly improve to VFR through the aftn with some
clearing by this evening, especially toward the coast. MVFR/IFR
cigs are expected to develop inland late tonight into early
Monday morning with the best likelihood of flight restrictions
at RIC. Additionally, vsby potentially falls to 3-5sm at RIC.
High pressure remains in vicinity of the coast Monday. Dry and
VFR Monday late morning into the aftn with increasing clouds as
an upper level impulse approaches from the NW. The wind will be
SE 5-10kt inland and ENE 5-10kt along the coast.

There is a chc of showers Monday night into Tuesday, especially
well inland away from the coast. Minimal chcs of showers persist
Tuesday through Friday. Generally VFR outside of any late
night/early morning fog/stratus.

&&

.MARINE...
As of 400 AM EDT Sunday...

Key Messages:

- Small Craft Advisories remain in effect for all coastal waters
through Monday (primarily for seas).

- Winds increase Sunday, but remain mainly sub-SCA. Waves may  build
to 4 ft late Sunday/Sunday night at the mouth of the  Bay.

- Persistent long period swells keep seas elevated into the   middle
of next week.

Sfc low pressure (~1004mb) lingers well off the northeastern coast
of the United States, with a 1022mb+ high pressure centered well to
the north, across northern Quebec and New Brunswick. Southeast winds
~10 kt (10-15 kt across the central and northern bay zones continue
into this morning. Winds become more easterly this afternoon 10-15
kt with perhaps a few gusts to around 20 kt. This is due to a weak
surface low which moves southeast across Virginia into eastern North
Carolina. Northeasterly winds 15-20 kt are expected across the
coastal waters and the lower bay. Sunday evening winds are expected
to decrease  to 10-15 kt. Across the bay waves are expected to grow
between 1-2ft (2-3ft occasional 4ft at the mouth of the bay) later
this afternoon and into the evening. Expect the north coastal water
seas to grow to 4-6ft and southern coastal waters 4-5 ft later this
afternoon and evening. Through this week expect the coastal waters
waves heights to slowly grow as a strong high pressure continues to
build in. Right now, small craft advisories remain in place
across the coastal waters til Monday. Possibly expect them to
remain in place through this week as seas build. Will note, at
this time confidence still remains too low for any headlines
(outside of 3-4 ft waves at the mouth of the Ches Bay). Real
time analysis and Model trends will continued to be monitored if
a headline needs to be issued for this zone.

&&

.TIDES/COASTAL FLOODING...
As of 430 AM Sunday...

- Key Message: Long duration coastal flood event continues
  across the region, with water levels expected to peak today
  and Monday. At least minor flooding is likely to persist
  through Tuesday, possibly into Wednesday in portions of the
  mid/upper Bay. Various headlines remain in effect (see latest
  CFWAKQ for details).

Tidal departures are currently running +1.5 ft to +2.0 ft above
astro tide levels. The high tides later today and and Monday
afternoon/evening look to be slightly higher than what has
occurred over the past 24hrs and as such, expect additional
rounds of moderate coastal flooding through Monday evening.

In general, the most widespread moderate flooding (potentially
near Major at a few places) will be over the mid/upper Bay,
including the tidal Potomac/Rappahannock and the MD eastern
shore through Monday evening. These locations may see moderate
coastal flooding continue into Tuesday as winds veer to the E-SE
and long period easterly swell remains in place over the ocean,
allowing water trapped in the Bay to shift northward.

Areas to the south across the lower Bay/tidal James and York
rivers will be more marginal, with peak water levels mostly in
high end minor flood thresholds or briefly touching moderate
thresholds. Have left the Warnings in effect in these areas but
did not extend these through Monday given low confidence.

Have opted to leave Norfolk and Chesapeake in a Coastal Flood
Advisory (as opposed to a Coastal Flood Warning) given that the
Elizabeth River and Sewell`s Point still look to remain below
moderate flood stage. A Coastal Flood Advisory also remains
across the Atlantic side of the Maryland Eastern Shore with
Ocean City looking to remain in minor flood stage through Monday
afternoon.

Additional headlines are likely to be needed for Tuesday, but
given uncertainty with respect to these being Warnings or
Advisories, did not extend the current headlines beyond Monday
night for now.

In addition, a High rip current risk is in effect through
Sunday and will likely be extended into Monday as well.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
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MD...Coastal Flood Warning until 2 AM EDT Wednesday for MDZ021>023.
     Coastal Flood Advisory until 4 PM EDT Monday for MDZ024-025.
NC...Coastal Flood Warning until 4 PM EDT Monday for NCZ102.
VA...Coastal Flood Warning until 4 PM EDT Monday for VAZ098.
     Coastal Flood Warning until midnight EDT Tuesday night for
     VAZ075-077.
     Coastal Flood Warning until 10 PM EDT Tuesday for VAZ076-078-
     085-521-522.
     Coastal Flood Advisory until 9 PM EDT Tuesday for VAZ083-518-
     520.
     Coastal Flood Warning until 6 PM EDT Monday for VAZ084-086-
     523>525.
     Coastal Flood Warning until 10 PM EDT Monday for VAZ089-090-
     093-096.
     Coastal Flood Advisory until 6 PM EDT Tuesday for VAZ095-097.
     Coastal Flood Warning until 8 PM EDT Monday for VAZ099-100.
MARINE...Small Craft Advisory until 1 AM EDT Monday for ANZ634.
     Small Craft Advisory until 6 PM EDT Tuesday for ANZ650-652-654-
     656-658.
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&&

$$

SYNOPSIS...AJZ/AM
NEAR TERM...AJZ
SHORT TERM...AJZ/AM
LONG TERM...AJZ
AVIATION...AJZ
MARINE...HET/LKB
TIDES/COASTAL FLOODING...AJZ