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621
FXUS61 KAKQ 111901
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
301 PM EDT Sat May 11 2024

.SYNOPSIS...
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Scattered showers push across central and eastern Virginia
toward the eastern shore this evening and late tonight, with
gradual clearing for Sunday. Dry and warmer weather to start
the week Sunday, before another round of showers and storms
return to the region Tuesday and Wednesday.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
As of 255 PM EDT Saturday...

Key Messages:

- Increasing clouds this afternoon and evening.

- Scattered to numerous showers push across the region this
  evening into the overnight hours, mainly north of US-460. Best
  rain chances will be north of Richmond over the Virginia
  northern neck and Maryland eastern shore.

Latest analysis shows weak 1015+mb sfc high pressure over the
mid south. To the northwest, ~1003mb surface low pressure over
SE Ontario into the eastern Great Lakes, with a trailing cold
front extending SSW across W PA and WV back into W KY/TN.
These showers will continue to drop SE toward the region for the
rest of the afternoon. Aloft, transient shortwave ridging will
briefly crest across the Atlantic coastal plain this afternoon
as the broad upper shortwave digs across SE Ontario into the
interior northeast through this evening. This feature does
eventually become hung up to our north late tonight into Sunday.

Clouds have diminished as expected across the piedmont to I-95,
with mid-level clouds hanging on along the coast in weak CAA.
18z Obs showing temperatures largely in the low to mid 60s along
the coast, mid to upper 60s inland, with some modest warming
expected through late afternoon.

The weakening cold front crosses the region tonight with
scattered to numerous showers expected. Have followed a time-
lagged HRRR blend for timing showers this evening. While showers
will be well-forced, forecast soundings not showing a whole lot
of moisture to work with, as PWs top out ~0.7-0.9". That said,
forcing for ascent should be able to wring out a quarter to as
much as half an inch of moisture across the northern neck and
eastern shore tonight, with a rumble of thunder or two also
possible this evening. Farther south, isolated to a few
scattered showers will be possible, but drier air and weaker
forcing should combine to help limit coverage over southern VA
into northeast NC. Mostly cloudy to start with decreasing clouds
overnight. Low temps early Sunday morning look to fall into the
upper 40s to low 50s.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
As of 255 PM EDT Saturday...

Key Messages:

- Clouds and showers linger across Maryland Sunday morning.

- Clearing for much of the area Sunday afternoon with milder
  temperatures Sunday and Monday.

- Clouds increase once again later Monday and Monday night, with
  rain chances returning late Monday evening west of I-95.

Showers linger across the MD eastern shore and VA northern neck,
as the upper trough axis slowly clears the region. Cooler temps
aloft will allow for a bit deeper convection and have
maintained a chance for thunder for the northern Ches Bay into
the Eastern Shore Sunday afternoon. Otherwise, subsidence behind
the departing wave and ridging building to the west should
combine for a clearing sky and a pleasant Mother`s Day across
the region. Dry with decreasing afternoon clouds and high temps
ranging from the mid 70s SW and S to the mid/upper 60s NE.
Drying out across MD Sunday night with lows in the mid 40s to
low 50s.

Bit of a transition day on Monday. Our next system, a closed
low over the southern plains approaches the mid-south Monday
into Monday night. Warm and dry on Monday in WAA as high
pressure slides off the SE coast. Highs in the mid 70s to low
80s. Low to mid level moisture increases from the SW Monday
night, with slight chance to chance PoPs spreading eastward
late Mon night into Tuesday as overrunning showers lift into
the region. Accordingly nudged up lows closer to the NBM 90th
percentile values in anticipation of increasing clouds/PoPs and
rising PW values. Lows mainly in the low to mid 60s under an
increasingly cloudy sky.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
As of 255 PM EDT Saturday...

Key Messages:

- Showers and storms return to the forecast Tuesday and
  Wednesday.

- Brief clearing behind the midweek system look to yield to a
  continued unsettled weather pattern for late this week into
  next weekend.

Partly to mostly cloudy on Tuesday ahead of a deep southern
stream trough. The local area will be solidly in the warm sector
of this system as showers and storms overspread the area
through the day. PoPs increase only across the western half of
the area initially, but do eventually reach the coast by Tuesday
afternoon and night. Highs will reflect that trend, with
warmest values across the eastern half of the area where precip
will hold off longest. Highs around 70 degrees in the Piedmont
with mid to upper 70s for areas east of I-95. Potential for
continued showers and storms overnight with lows in the low to
mid 60s.

The upper low and surface reflection will be slow to cross the area
Wednesday with continued chances for showers and storms.
Temperatures will be warm with highs in the 70s to low 80s with
overnight lows in the mid 50s to low 60s. High pressure builds in
briefly on Thursday but another system approaches late in the week
with another chance for scattered showers and storms. High temps
remain in the 70s to low 80s with lows around 60.

&&

.AVIATION /19Z SATURDAY THROUGH THURSDAY/...
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As of 255 PM EDT Saturday...

VFR at all terminals to begin the 18z TAF period. Light SSW
winds inland with E-NE winds along the coast. Another system
approaches from the NW this evening, bringing additional chances
for scattered showers and perhaps a rumble of thunder tonight
(best thunder chances are NE of RIC and W of KSBY). Precip will
be focused from RIC-PHF north to SBY after 22z, with
diminishing/weakening showers possibly reaching KECG and KORF
after 01-03z.

Outlook: Dry for most terminals tomorrow. Isolated to scattered
showers and storms are possible across NE portions of the FA
(including around SBY). Dry conditions return region-wide on
Monday. However, unsettled weather returns Tue-Wed as another
low pressure system approaches the FA.
-- End Changed Discussion --

&&

.MARINE...
As of 255 PM EDT Saturday...

Key Messages:

-Prevailing sub-advisory conditions expected to persist through at
least Monday evening

-Additional SCAs possible ahead of a low pressure system

Low pressure has pushed well offshore a high pressure has briefly
built in over the area. Latest obs reflect light onshore winds at
~5kt in the bay and rivers and 5-10kt over coastal waters. Seas are
improving, but onshore flow is making the drop off gradual. Latest
buoy obs show seas between 4 and 5 ft off the VA and MD coast, but 5-
6ft off the NC coast. Based on the rate that seas are diminishing,
the remaining SCA should be okay to expire on time (4pm), but will
monitor and issue an extension if needed. A weak front will move
across the region late tonight into early tomorrow. Ahead of the
front, winds turn to the SE, then S, and pick up to 10-15kt. Winds
turn to the NW behind the front tomorrow, staying at 10-15kt through
the afternoon. High pressure returns Sunday night into Monday,
resulting in light onshore winds once again. A stronger front/low
pressure system looks to cross the region mid-week. This will bring
another chance for SCA conditions as winds increase ahead of the
system. SCAs may be needed as early as Monday night on the bay,
given local wind probs showing ~45% for sustained winds of 18kt.

Seas will stay around 4ft tonight and through tomorrow, then drop to
3ft by early Monday. Seas increase back to 4ft Mon night, then 5ft
ahead of the mid-week system. Waves will be 1-2ft through tonight,
increasing to 2-3ft tomorrow afternoon. Waves drop back to 1-2ft Sun
night before returning to 2-3ft Mon afternoon.

&&

.TIDES/COASTAL FLOODING...
As of 255 PM EDT Saturday...

Key Messages:

-Coastal Flood Advisories continue through tonight/early Sunday AM
for all areas adjacent to the middle/upper Chesapeake Bay.

-Minor to locally moderate tidal flooding (inundation of 1 to
locally 2 feet above ground level in vulnerable areas) is expected
during high tide tonight into early Sunday.

-Coastal Flood Statements have been added to areas adjacent to the
upper (tidal) James River for tonight`s high tide.

With winds becoming SE then S later today and tonight, tidal
anomalies will fall in the lower Ches Bay and along the Atlantic
coast, while rising a bit in the mid/upper bay (combined with
already high astro tides). Widespread minor to locally moderate
tidal flooding is expected tonight/early Sunday AM in the mid/upper
bay, with mostly nuisance flooding farther south. Coastal Flood
Advisories continue until Sunday AM from Mathews County north to
Lewisetta in addition to the bay side of the MD Eastern Shore. At
this time, it looks like Lewisetta, Crisfield, and Bishop`s Head
stand the best chance of seeing (low-end) moderate flooding tonight,
but confidence is low. A Coastal Flood Statement has been added for
areas adjacent to the upper James River, since the Jamestown gage
looks to briefly hit minor flood stage with tonight`s high tide.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...Coastal Flood Advisory until 11 AM EDT Sunday for MDZ021>024.
NC...None.
VA...Coastal Flood Advisory until 8 AM EDT Sunday for VAZ075>078-
     085-086-521-522.
MARINE...Small Craft Advisory until 4 PM EDT this afternoon for ANZ656-
     658.

&&

$$

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