418
FXUS61 KAKQ 051540
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
1140 AM EDT Wed Jun 5 2024

.SYNOPSIS...
Unsettled weather continues through Thursday with daily chances for
scattered showers and thunderstorms. A cold front pushes through
late Thursday into Thursday evening, bringing drier conditions
for Friday into the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1140 AM EDT Wednesday...

Key Message:

- Warm and muggy today. Warmest readings likely over southern VA
  into northeast NC, where highs will approach the upper 80s to
  near 90.

- Scattered showers and thunderstorms are expected through this
  evening. A few stronger storms are possible, but locally heavy
  rainfall remains the main threat from any of today`s storms.

Latest analysis ~1020mb high pressure off the mid-Atlantic
coast. To the NW, deepening ~986mb sfc low pressure was analyzed
over the Canadian Prairies, with a weak quasi- stationary
boundary extending SSE across the upper Great Lakes and
along/just S of the Mason-Dixon line to the lower eastern shore.
Aloft, a dampening upper level ridge has built over the eastern
seaboard, with qusi-zonal mid-level low over the region. The
first in a series of shortwave troughs/MCVs is pushing offshore
of the eastern VA coast. The second, centered over the central
Appalachians into the VA piedmont, will cross (mainly) north of
the region from SW to NW through this evening, with the third,
extending from the OH River Valley into the mid-South, crosses
the region this evening into the early overnight hours (~00-06z).

Temperatures vary from low to mid 70s across the northern and
central CWA, with low to mid 80s across the US-58 corridor of
southern VA into NE NC.

CAMs are generally struggling with convective signal, mainly a
result of the weak forcing and minimal instability at the
moment. Scattered showers will continue over the northern neck
and eastern shore through early afternoon as the initial
shortwave crosses. Meanwhile, showers develop along and W of
I-95 over the next couple of hours with the second disturbance.
Given PW in the 1.6-1.8" range, locally heavy rainfall is the
main hazard, especially as better deep-layer shear values look
to remain along and just north of our area over to the eastern
shore (a Marginal Risk from SPC remains across our far northern
tier of counties). That said, it does appear possible that a
few stronger storms will also be possible along a differential
heating boundary that could very well develop this aftn across
far SE VA into NE NC. PoPs remain in the 20-40% range over much
of the area, ticking up into likely range across our northern
tier of counties from Louisa to Caroline and
Richmond/Westmoreland counties (VA) over to the MD eastern
shore. Given the multiple perturbations crossing the region and
the moist antecedent airmass, areal coverage (ISO- SCT wording)
remains the best fit for the forecast this afternoon, with
showers and storms of the pulsy, loosely organized convection of
the hit- or-miss variety the expected storm mode.

The greatest coverage and intensity of convection slides over
the SErn counties this evening. While CAMs remain frustratingly
split on this as of this writing, modest instability, a small
uptick in lapse rates and the crossing shortwave all point to
this area for an uptick in areal coverage of showers and storms
(30-40%), with an isolated stronger storm or two possible in the
respective wet microbursts.

Highs today generally 80-85 north, and 85 to 90 across far S/SE
zones.

The last shortwave crosses the area this evening, with
additional scattered showers expected. Rain chances taper late
as the wave weakens and exits. Some spotty low stratus and fog
is likely, and will add mention of patchy fog overnight for the
afternoon package. Lows late tonight in the upper 60s to low
70s under a partly to mostly cloudy sky.

&&

.SHORT TERM /THURSDAY THROUGH THURSDAY NIGHT/...
As of 330 AM EDT Wednesday...

Key Messages:

- Remaining warm and humid Thursday.

- Showers and storms overnight followed by more numerous
  showers and storms Thursday afternoon.

- Locally heavy rain is possible both Wednesday and Thursday.

The WPC Excessive Rainfall Outlook remains in place for
portions of the area Thursday. There remains a very low chance
for an isolated severe storm or two, but with kinematics rather
weak given the expected multiple rounds of convection and
overall weak bulk shear, heavy rain/flood potential remains the
primary hazard.

Showers and storms should taper off later this evening with
another wave of showers possible overnight with an upper
shortwave. More showers and storms redevelop Thu late
morning/afternoon as the cold front approaches the area. The
best chance for a few strong to severe storms Thu is across
eastern VA and NE NC, where likely PoPs (60-70%) remain in
place. Any storms move offshore by Thu night as drier air moves
into the region behind the front. Gusty winds, frequent
lightning and locally heavy rainfall are the main hazards Thu.
SPC Day 3 Risk remains in the General Risk category, largely due
lingering uncertainties regarding exact timing. Highs in the
mid to upper 80s Wed (highest SE) and upper 80s to lower 90s Thu
expected.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
As of 300 AM EDT Wednesday...

Key Messages:

- Drier weather returns Friday into early next week, with near
  to below normal temperatures appearing likely over the weekend
  into early next week.

Drier weather moves in Fri behind a cold front as dewpoints drop
into the 50s. Pleasantly cooler and drier Friday night into
Saturday, with dry weather expected. Aloft, an upper level low
moves into the Great Lakes on Fri, lingering into early next
week. Latest GEFS/ECS continue to jostle for when the next
(weak) cold front drops into the area. Either way, it appears
the upper level low is too close to the local area for enough
instability for much in the way of widespread showers and/or
storms on Sunday. Instead, only a slight chance for a few
isolated showers/storms exists late Sun, with slight to low-end
chance PoPs continuing Mon and Tue. Highs mainly in the lower to
middle 80s with lows in the upper 50s to 60s.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
As of 330 AM EDT Wednesday...

VFR conditions prevail as of 06z with a SE wind of 5-10kt at
RIC, and SE to E 5-10kt toward the coast. The marine layers has
been slow to push across the eastern shore with a few sites
south of SBY reporting IFR ceilings. Will have to monitor sites
near the ocean and Bay to see if more IFR ceilings or fog push
into the region from the east. Isolated showers were developing
southwest of RIC, but these will likely stay away from the
airport at least through the next few hours. More scattered
showers and storms increasing in coverage will develop later
this morning and through the afternoon. Expect more ceiling
BKN040 this afternoon with cu and convection. We should see a
break in showers later this evening with another rough of
scattered showers possible overnight.

More scattered showers/tstms are expected once again Thursday
late morning and into the afternoon as a cold front approaches
from the west. Mainly dry Friday through Sunday behind the font,
with VFR likely prevailing for much of Friday through Sunday.

&&

.MARINE...
As of 300 AM EDT Wednesday...

Key messages:

- Small Craft Advisories in effect for the Chesapeake Bay and
  lower James River starting late this evening ahead of a cold
  front that will cross the area Thursday night.

- Chances for showers/storms could cause locally higher winds and
waves today and Thursday.

-Low rip current risk today, trending toward moderate risk at
northern beaches Thursday.

A large area of sfc high pressure situated offshore early this
morning with a subtle warm front pushing N along the coast. Latest
obs indicate winds out of the SE at 5-10kt. Today, high pressure
will slowly get pushed farther out to sea as a cold front gradually
approaches the Mid-Atlantic from the NW. Breezy conditions are
expected by late afternoon as the pressure gradient tightens. Winds
will gradually become more southerly and increase to 10-15kt in the
afternoon, then 15-20kt later in the evening. Tonight, winds will
turn to the SW as high pressure offshore is pushed S. Sustained
speeds increase to near 20kt in the bay and coastal waters after
midnight (~15kt in rivers/Currituck Sound) with gusts up to 25kt.
Thus, SCA are in place for the bay and lower James starting late
this evening and in effect through Thursday morning. Will note that
there is the potential for higher wind gusts given the presence of a
LLJ around 40kt. However, weak lapse rates over the waters tonight
suggests these higher speeds will have a hard time mixing down.
Conditions will improve through the day Thursday, though still
remaining breezy with southerly winds at 10-15kt. The cold front
crosses the waters Thursday night, turning winds to the W by Friday
morning at 5-10kt. High pressure then gradually builds in from the
SW through the weekend. Sub-SCA conditions expected over the weekend
with winds varying between NW and SW and 5-15kt. Showers and
thunderstorms are expected both today and Thursday, which may cause
locally higher winds and waves.

Seas are around 2ft this morning and waves are 1ft or less. As winds
increase today, waves build to 1-2ft seas 2-3ft by the afternoon.
Tonight, waves will be 2-3ft in the bay and 1-2ft in the
rivers/sound. Seas build to 3-4ft with the potential for 5ft seas
out near 20nm in northern waters. Waves fall back to 1-2ft by
Thursday afternoon. Seas stay at 3-4ft through Thursday evening,
then fall back to 2-3ft Friday. Rip current risk will be low at all
area beaches today. Rip risk increases at Eastern Shore beaches
Thursday.

&&

.TIDES/COASTAL FLOODING...
As of 415 AM EDT Wednesday...

Some shallow / nuisance coastal flooding remains possible
during the higher high tide cycles early Thursday morning where
Cambridge, Bishops Head, and Crisfield all could near 3.5 ft
MLLW, which is minor flooding at these sites. Coastal Flood
Statements will likely be needed for the bay side of the MD
Eastern Shore. Otherwise, most tidal sites in the middle and
lower bay, including up the James River, may see only very
shallow flooding near the waterfront over the next couple days.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory from 10 PM this evening to 10 AM EDT
     Thursday for ANZ630>632-634.
     Small Craft Advisory from 4 AM to 10 AM EDT Thursday for
     ANZ638.

&&

$$

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