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186
FXUS61 KAKQ 121501
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1101 AM EDT Sun May 12 2024

.SYNOPSIS...
Scattered showers are possible for the Eastern Shore today ahead
of an upper trough. Dry and warmer to start the work week
before another round of showers and storms returns to the
region Tuesday and Wednesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
As of 1100 AM EDT Sunday...

Key Messages:

- Warm and dry for most of the area with plenty of sunshine.

- Showers and a few storms are possible across the eastern
  shore this afternoon ahead of an approaching upper trough.

Latest analysis reveals weak ~1009mb low pressure over north
central PA late this morning, with a cold front extending
southward across the Maryland eastern shore. Latest area of
showers in association with the upper trough axis is nudging off
the Atlantic coast of lower Maryland as of this writing. Will
have a brief lull through early afternoon, when clouds increase
again over the eastern shore. Cooler temps aloft/steeper mid
level lapse rates and ascent ahead of the crossing upper trough
continue argue for isolated to scattered showers and storms to
re-fire over the MD Eastern Shore this afternoon, and incoming
12z CAMs continue to show this occurring, focused along and just
ahead of the cold front after 18-19z/2-3 PM EDT. Farther south,
subsidence behind the passing trough and high pressure building
to the SSW will bring plenty of sunshine over the SW 2/3 of the
area this afternoon. Nudged highs upward slightly in anticipation
of strong aftn mixing (MIN RH in the 20s to around 30% this
aftn inland across the piedmont). High temps range from the mid-
upper 70s near and south of I-64 to the 60s and low 70s for
areas to the north. Coastal portions of the MD eastern shore
near Ocean City may struggle to warm much above 60 degrees this
afternoon with onshore flow and more clouds.

Dry tonight with skies clearing out behind the departing
trough. Some patchy fog possible late on the eastern shore and
over the VA northern neck. Early morning low temps fall into
the mid to upper 40s inland, upper 40s to low 50s along the
coast.
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&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 330 AM EDT Sunday...

Key Messages:

-Dry and warm on Monday.

-Next system moves in Tuesday with showers and thunderstorms.
 Widespread severe weather is not expected.

High pressure builds over the region Monday, bringing warmer
temperatures and dry conditions. High temps climb back into the 70s
to low 80s. Clouds increase late in the afternoon from the SW ahead
of our next system. A closed upper low and weak surface low will
translate eastward Monday night with lows only in the upper 50s to
low 60s under mostly cloudy skies. Rain chances look to hold off
until after midnight across the Piedmont.

PoPs increase quickly from west to east Tuesday morning as deeper
moisture overspreads the area. Showers and storms are likely Tuesday
afternoon and evening but limited instability and deep layer shear
will keep chances for severe weather low. Highs Tuesday range from
the low 70s in the Piedmont to the mid 70s closer to the coast. The
heaviest rainfall likely occurs after sunset Tuesday with average
QPF ranging from 0.5-1" across the region. Mild overnight with
temps in the low to mid 60s.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 330 AM EDT Sunday...

Key Messages:

-Showers and storms linger on Wednesday before moving offshore
 overnight.

-Continued warm late this week with increasing chances for showers
 and storms Friday and Saturday.

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 on Friday with
another chance for scattered showers and storms. High temps remain
in the 70s to low 80s on Thursday and Friday with low to mid 80s on
Saturday. Overnight lows continue around 60 degrees.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
As of 645 AM EDT Sunday...

VFR conditions will dominate through the 12z TAF period. MVFR
and IFR CIGs have been impacting RIC and vicinity early this
morning but should mix out over the next hour or two. Will
include TEMPO IFR CIGs at RIC through 13z. Additional showers
with embedded thunder are noted over the DC region, drifting SE
toward SBY. Not confident in thunder chances at the terminal.
Will limit mention to -SHRA with MVFR CIGs for now but a few
rumbles of thunder are possible at SBY through 14-15z.
Additional showers and storms are again possible at SBY this
afternoon as the upper trough axis moves through. Light and
variable winds outside of convective influences this morning,
becoming NW around 10 kt with gusts 15-20 kt by mid to late
morning through the afternoon. Clearing skies and VFR
conditions are expected tonight with light and variable winds.

Outlook: Dry conditions return area-wide on Monday. However,
unsettled weather returns Tue-Wed as another low pressure
system approaches the FA.

&&

.MARINE...
As of 330 AM EDT Sunday...

Key Messages:

-Prevailing sub-advisory conditions are expected to persist through
Monday

-Additional SCAs possible ahead of a low pressure system Monday
night and more likely Tuesday into Wednesday morning

Low pressure to our north (over PA/NY) will continue to track SE
today. SE winds are 10-15kt with gusts to 20kt at this hour, but
will turn to the NW today (and remain 10-15kt) as the low to our
north drags a front through the area. High pressure returns tonight,
allowing winds to become NE at 5-10kt. Winds then increase out of
the S-SE on Monday as that high moves well offshore. In fact, a
brief period of low-end SCA conditions is possible Monday night, and
local wind probs are now showing a 40-60% chc of sustained 18kt
winds on the Ches Bay between 7 PM Mon-2 AM Tue. Won`t issue
headlines attm as the event appears marginal and it is in the 4th
period. Seas subside to to ~3ft today before building back to 4ft by
Mon night.

S winds briefly diminish to 10-15kt Tuesday AM. However, a low
pressure system is progged to approach the area on Tuesday before
crossing the area from west to east Tuesday night/early Wednesday.
The pressure gradient will increase ahead of the system by Tue
aftn/evening, allowing S winds to increase to ~20kt (and remain
around 20kt through most of Tue night). Local wind probs show an 80-
100% chc of 18kt winds on the bay Tue night. In addition, seas build
to 5ft ahead of the mid-week system. Sub-SCA conditions are expected
behind the system Wed night-Thursday (w/ N winds near 15kt and seas
subsiding to ~4ft). Waves on the bay will be 1-3ft through most of
the period (although 4ft waves are possible Tue night).

&&

.TIDES/COASTAL FLOODING...
As of 330 AM EDT Sunday...

Key Messages:

-Coastal Flood Advisories remain in effect through this morning 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 this morning`s high tide in the advisory area.

Tidal anomalies have fallen a bit in the lower bay and along the
Atlantic coast with the S-SE winds, but remain elevated in the
mid/upper Ches Bay. Coastal Flood Advisories continue through this
morning from Mathews County north to Lewisetta in addition to the
bay side of the MD Eastern Shore. At this time, it looks like
Lewisetta/Bishop`s Head stand the best chance of seeing (low-end)
moderate flooding early this morning, but confidence is low. A
Coastal Flood Statement remains in effect for the upper James River,
as water levels in Jamestown appear to be cresting right around
minor flood thresholds. Not expecting anything worse than nuisance
flooding in the mid/upper bay (with no tidal flooding farther south)
over the next few days.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Coastal Flood Advisory until 11 AM EDT this morning for
     MDZ021>024.
NC...None.
VA...None.
MARINE...None.
-- End Changed Discussion --

&&

$$

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