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368
FXUS61 KAKQ 230718
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
318 AM EDT Mon Sep 23 2024

.SYNOPSIS...
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.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 315 AM EDT Monday...

Key Message:

-Cloudy, but overall pleasant day with highs in the 70s.

-A chance for showers tonight, especially west of I-95.


Early morning sfc analysis indicates high pressure centered over New
England/Eastern Canada ridging down the Atlantic coast and into the
local area. Meanwhile, persistent low pressure well offshore is
finally making progress on its journey south. Aloft, a ridge is
nudging into the local area. Through the day today, the ridge axis
aloft will slide in overhead while the sfc high continues to wedge
itself down the coast.

Cloud cover has been a little slow to build back in from the west
tonight. As a result, temps are running a bit cooler than
anticipated between I-95 and the immediate coastal area. Latest obs
show these locations in the upper 50s. Further inland, where clouds
have filled in, temps are in the low-mid 60s. A few obs are showing
fog, but this shouldn`t be as widespread as yesterday morning.
Clouds will stick around through the day, especially inland. Due to
the thicker cloud cover, temps will run on the cooler side with
highs in the low to mid 70s. Warmer in the east with highs in the
mid-upper 70s. Onshore flow continues today, so immediate coastal
areas will also run on the cooler side. Regarding precip, the
daytime hours should largely remain dry, but cannot completely rule
out a stray shower on the western edge of the FA. A weak shortwave
trough will travel up the ridge aloft tonight, which may act to
trigger showers in the area. However, high pressure at the coast
will act to limit precip, especially E of I-95. Have Chc PoPs
entering the western counties late this evening and sticking around
through the night. Lows tonight will be in the low-mid 60s.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
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.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
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.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
As of 150 AM EDT Monday...

VFR conditions prevail across the terminals to start the 06z
TAF period as high pressure ridges down the Atlantic coast.
While cloud cover is still expected to increase later tonight,
there is less confidence regarding flight restrictions at RIC
and whether or not the thicker cloud cover will make it to the
coast. Guidance now keeps MVFR/IFR west of RIC tonight. Did not
completely remove the MVFR from the TAF, but have trended it
toward less impact. Elsewhere, not expecting flight restrictions
within the TAF period outside of brief, shallow ground fog.
Winds look to remain light through the period and generally out
of the E.

There is a chc of showers late Mon evening into Tue, esply well
inland away from the coast. Minimal chcs of showers persist Tue
through Fri. Generally VFR/MVFR outside of any late night/early
morning fog/stratus.

&&

.MARINE...
As of 340 PM EDT Sunday...

Key Messages:

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

-A Small Craft Advisory is in effect for the mouth of the bay through
 1 AM tonight for elevated waves.

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

-Northeast winds may become elevated next weekend.

Sfc low pressure lingers well off the Mid Atlantic and New England
coast, with high pressure centered well to the north, across
northern Quebec and New Brunswick. Winds were generally E/NE 10-15
kt with occasional gusts up to 20 kt across the local waters this
afternoon. The pattern does not change much over the next couple of
days with winds remaining 10-15 kt through Mon, diminishing to ~10
kt Tue. Winds remain sub SCA level (mainly SE) through Thu before
becoming NE Fri. Models are coming into better agreement regarding
an enhanced NE flow developing next weekend with SCA winds possible.
We will continue to monitor and see how this trends.

Waves and seas were generally 1-2 ft (2-3 ft across the lower bay
and 3-4 ft across the mouth of the bay) and 4-6 ft respectively this
afternoon. Expect seas to remain elevated (4-7 ft) into at least the
middle of the week (and possibly through next weekend). For now,
have extended SCAs across the coastal waters through Tue with future
extensions likely. Have also added a SCA for the mouth of the bay as
waves at the First Landing buoy have been 4-5 ft this
afternoon. While these wave heights are locally high compared to
nearby buoy observations, at least 3-4 ft waves at the mouth of
the bay appear likely to continue into this evening. As such,
SCAs here are in effect until 1 AM tonight.

&&

.TIDES/COASTAL FLOODING...
As of 340 PM Sunday...

- Key Message: Long duration coastal flood event continues
  across the region, with water levels expected to peak this
  afternoon 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 this afternoon and Monday
afternoon/evening look to be the highest with locally moderate
coastal flooding possible across much of the coastal waters. 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. As such, Coastal Flood Warnings have been
extended through Tuesday evening.

Areas to the south across the lower Bay/tidal James and York rivers
will be more marginal, with peak water levels mostly in the high end
minor flood to locally moderate thresholds. However, given that
tidal anomalies remain fairly consistent, Monday`s high tide
should be comparable to this afternoon`s high tide. As such,
have extended Coastal Flood Warnings here through Monday
afternooon`s high tide.

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 and
Wednesday in spots, but uncertainty is higher than for Monday across
the middle and lower bay.

In addition, a High rip current risk is in effect through Monday.
This may need to be extended for Tuesday.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Coastal Flood Warning until 2 AM EDT Wednesday for MDZ021>023.
     Coastal Flood Advisory until 4 PM EDT this afternoon for
     MDZ024-025.
NC...Coastal Flood Warning until 4 PM EDT this afternoon for NCZ102.
VA...Coastal Flood Warning until 4 PM EDT this afternoon 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 this evening for VAZ084-
     086-523>525.
     Coastal Flood Warning until 10 PM EDT this evening for VAZ089-
     090-093-096.
     Coastal Flood Advisory until 6 PM EDT Tuesday for VAZ095-097.
     Coastal Flood Warning until 8 PM EDT this evening for VAZ099-
     100.
MARINE...Small Craft Advisory until 5 AM EDT early this morning for
     ANZ634.
     Small Craft Advisory until 6 AM EDT Wednesday for ANZ650-652-
     654-656-658.
-- End Changed Discussion --

&&

$$

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