361
FXUS61 KAKQ 161353
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
953 AM EDT Fri Aug 16 2024

.SYNOPSIS...
Seasonably warm today and dry through the evening.
Precipitation chances gradually return to the region from Friday
night through the weekend, as a slow moving area of low
pressure and series of fronts cross the region.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 945 AM EDT Friday...

Key Messages:

- Seasonably warm today with highs in the mid/upper 80s with increasing
  clouds this evening.

- Scattered showers and perhaps an isolated storm or two are possible
  late tonight into early Saturday morning.

Sfc analysis depicts high pressure off the East Coast this
morning. This high will gradually slide off the coast through
the day. Aloft, a weak ridge moves E across the Great Lakes with
a trough off the East Coast moving E. A shortwave moves E
tonight into Sat morning with scattered showers (and perhaps an
isolated storm or two) possible overnight. CAMs generally agree
on a line of showers passing through the FA late tonight into
the early morning from W to E. Highest coverage would likely be
across N counties. However, most of the day is expected to be
dry and warm with highs in the upper 80s for most (potentially
around 90F at Richmond). Lows tonight in the upper 60s to around
70F expected for most with mid-upper 60s possible across SE
VA/NE NC and the Eastern Shore (where less cloud cover is
expected).

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
As of 305 AM EDT Friday...

Key Messages:

- Seasonably warm with increasing humidity.

- Increasing chances for showers/storms though the weekend as a
  series of weak cold fronts pass through.

Rain chances ramp up through the weekend into Monday, as a series of
weak cold fronts push into the area and the parent upper low slowly
approaches from the west. PoPs are mostly dry for most of the day
Saturday, then precip chances increase (30-50%) in the late
afternoon, evening and overnight. Highs on Sat will once again be in
the mid/upr 80s. Humidity will increase as dewpoints rise into
the low 70s. Will note that SPC has trimmed back the marginal
severe risk for Sat, so now it only clips the far NW part of the
FA.

Coverage of showers/storms looks to be higher on Sun with as the
parent low and trough axis moves closer to the area, with better
forcing pushing in by afternoon and evening. PoPs will be up to
around 50-60% over the entire area in the afternoon. There could
easily be a few stronger storms as well, with LREF showing SBCAPE
~1000-1500 J/kg with 25-35 kt of deep layer shear. Precip will end
from W to E Sun night. Highs Sun in the mid 80s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
As of 305 AM EDT Friday...

Key Messages:

- Warm and humid on Monday with another chance for afternoon
  thunderstorms.

- Returning to cooler, drier pattern for the midweek period.

Overall, the long term looks to be cooler and drier as a rather
strong UL trough (for this time of year at least) sticks around over
the East Coast for several days. A cold front will cross through the
area and slide offshore Monday/Monday night. The front will likely
trigger scattered thunderstorms during the afternoon and early
evening hours. PoPs are in the 40-50% range with the highest
coverage in the NW half of the FA. Monday is likely the warmest day
of the week with highs in the mid-upper 80s. Cool high pressure
builds in behind the front from the NW Tues and gradually slides
east through the week. Temps look to be several degrees below norms
through at least Thurs. Highs will be in the low 80s Tues-Thurs.
Blended guidance actually shows that some locations may not even
reach 80 Tues-Wed. This period will be mostly dry, but cannot rule
out a few showers E of I-95 Tues afternoon.

&&

.AVIATION /14Z FRIDAY THROUGH TUESDAY/...
As of 200 AM Friday...

VFR prevails through the period as high pressure gradually
slides offshore today into tonight. SCT high level clouds will
be present through the afternoon, then cloud cover increases
from NW to SE tonight into Sat morning. Latest sfc obs have been
showing brief MVFR vsbys around the FA this morning, but not
expecting this to become widespread. Thinking SBY is the most
likely of the terminals to see some patchy fog this morning.
Winds will be calm to light and variable this morning, then
picking up to 5-10kt out of the S/SE this afternoon.

Outlook: A slow moving cold front will approach from the west
late Friday through Sunday with chances for mainly aftn/evening
showers/tstms each day, especially Sunday.

&&

.MARINE...
As of 400 AM EDT Friday...

Key Messages:

- Quiet conditions to start today, with elevated southerly winds
  developing late today through Saturday night. SCAs are
  possible in the Bay Sat aftn/Sat night for 20-25kt wind gusts
  (best chance N of New Pt Comfort).

- Small Craft Advisories are in effect for all coastal waters
  starting tonight north of Cape Charles, with the remaining
  coastal waters starting on Saturday as swells from Hurricane
  Ernesto reach the coast (this will also affect at least the
  Mouth of the Bay with 3-4 ft waves by Sat night/Sunday).

High pressure from NY/PA south into the Carolinas will shift off
the coast today. Winds are generally from SW at 5-10 kt but
will become light northerly later this morning, before
increasing from the SE late in the aftn. With high pressure
offshore and low pressure with a cold front approaching from
the midwest, expect to see enough tightening of the pressure
gradient for S winds 10-15kt with gusts to 20 kt tonight, and
winds a little higher Sat aftn/Sat night. SCA conditions from
wind are most likely in the Ches Bay north of New Pt Comfort.
Meanwhile, Hurricane Ernesto, currently well NE of the Bahamas,
is forecast to lift NNE, tracking to near Bermuda by early Sat.
Impacts locally will be restricted to increasing swell and the
threat for deadly rip currents. SCA flags start for the
Atlantic waters north of Cape Charles Light at 02z/10pm
tonight, with the remaining Atlantic waters starting SCAs by Sat
aftn. It is more marginal/uncertain at the mouth of the Bay but
expect additional small craft headlines will be needed by Sat
night/Sunday for ~4ft waves.

Seas Saturday will average 5-7 ft N of Cape Charles, and 4-5 ft
to the south, while then averaging 5-6 ft all areas late Sat
night through Sunday. Waves near the mouth of the bay will
increase as well, generally 2-3 ft on Saturday with 3-5 ft
possible late Sat night into Sunday before things start to calm
down Monday (though will likely have seas offshore linger at 4-5
ft possibly into early Tuesday). The models are in decent
agreement that another eastern CONUS upper trough develops next
week, allowing a cold front to move through the local waters Mon
night/Tuesday with winds shifting to the N/NW. Current models do
not show more than 10-15kt of wind Mon night/Tue, but as the
details become more precise, would expect winds to be stronger
given good mixing as rather cool air (by August standards) moves
over the warm waters.

&&

.TIDES/COASTAL FLOODING...
As of 420 AM EDT Friday...

Key Message:

-  A Moderate Risk of Rip Currents today, with a High Rip Risk
   likely for both Saturday and Sunday as long period swell from
   distant Hurricane Ernesto affects the region.

The latest 16/00Z run of the NWPS supports high rip risk for
all Atlantic coastal zones for the weekend given seas of 4-6 ft
with a dominant period of 13-15 seconds. Today begins low with
seas only 1-2 ft, but with the building seas to ~3 ft or 3-4 ft
this aftn, and an increase in the wave period, will have a
Moderate rip risk in effect today. Some minor tidal flooding
will be possible along the Bayside of the MD eastern shore by
Sun/Mon as the persistent long period swell may help trap water
in the Bay for several tide cycles (the southerly wind direction
favors transporting any trapped water northward).

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory from 10 PM this evening to 6 AM EDT
     Monday for ANZ650-652-654.
     Small Craft Advisory from noon Saturday to 6 AM EDT Monday for
     ANZ656-658.

&&

$$

SYNOPSIS...AM/MAM
NEAR TERM...RMM
SHORT TERM...AM/MAM
LONG TERM...AM
AVIATION...AM
MARINE...LKB
TIDES/COASTAL FLOODING...