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FXUS61 KAKQ 042008
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
408 PM EDT Sat May 4 2024

.SYNOPSIS...
On and off shower chances are expected this afternoon into
Sunday night. Summerlike conditions return to the area for next
week with daily chances of showers and storms.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
As of 400 PM EDT Saturday...

Late this aftn, a backdoor front was located south and west of
the CWA. While, high pressure just off the New England coast was
wedging cool, moist air into the Mid Atlc. That wedge will
gradually erode from WSW to ENE tonight through Sun, as a warm
front slowly moves ENE through the region. More energy, moisture
and lift will push back into the area from the W and S this
evening into Sun morning, with the highest PoPs for showers
(isolated thunder) over the wrn half of the CWA. Lows will be
in the lower to mid 50s across the N, and in the lower to mid
60s in the S.
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&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY NIGHT/...
-- Changed Discussion --
As of 400 PM EDT Saturday...

Key Messages:

- Continued unsettled, but warmer, Sunday.

- More humid Monday/Monday night with showers and storms
  areawide.

The front (as a warm front) will move ENE and north of the area
Sun into Sun evening, shifting the low-level flow to the S. These
factors should act to scour out the dreary conditions. However,
still expecting showers and some tstms to redevelop for later
Sun morning into Sun evening (PoPs 30-70%). PoPs will diminish
later Sun evening into Sun night. Highs on Sun will warm into
the 70s across the region. Lows Sun night in the lower to mid
60s.

Upper heights begin building back N for Mon with high temps
warming into the upper 70s to lower 80s. Despite the warmer
temps, a lee trough is expected to develop in the aftn and
evening hours. Combined with an approaching shortwave from the
OH River Valley, showers and storms are expected to develop over
the higher terrain in the aftn, then slide eastward into Mon
evening/night. Mean LREF CAPE shows ~750 J/KG, but shear looks
to be rather weak. Therefore, the severe threat looks relatively
low, but cannot rule out a stronger storm or two. Soundings do
show a rather saturated atmospheric column (PWATS potentially
reach or exceed 1.5"), which could lead to some heavier
downpours. Dew points also increase into the mid to upper 60s,
so the humidity will make it feel more like early summer.
Shower/storm activity diminishes inland after midnight, but may
linger closer to the coast overnight. Lows Mon night mainly in
the lower to mid 60s.
-- End Changed Discussion --

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
As of 400 PM EDT Saturday...

Key messages:

-A summer-like pattern will bring unsettled conditions and above-
normal temps.

-There is the potential for severe weather mid to late week.

An unsettled, summertime pattern takes over through the end of the
week. A ridge aloft builds in Tuesday, then weakens slightly
starting Wednesday. The GFS and ECMWF both suggest stronger 500mb
flow of up to 50 kt by Wed afternoon. Additionally, several waves of
weak shortwave energy will pass over the area. As of latest
guidance, the strongest of these looks to pass on Thursday ahead of
an UL trough dropping into the Great Lakes. A stronger system (i.e.
cold front) will then cross the area late in the week. These
features along with plentiful daytime heating/instability will allow
for daily rounds of showers/thunderstorms. Will be monitoring this
time period for severe weather given the support aloft and steep mid-
level lapse rates. The CSU Machine Learning Probabilities have
picked up on the aforementioned parameter space and suggest at least
a slight risk for severe weather on Wednesday and Thursday for the
entire area and Friday for southern/southeast areas. Highs on Tues
will be in the upper 70s on the Eastern Shore and low 80s W of the
bay. Well-above normal temps on Wed/Thurs with the potential for
widespread 90 degree highs. Fri looks a bit cooler, but still in the
80s for most. Lows generally in the mid-60s.
-- End Changed Discussion --

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
As of 230 PM EDT Saturday...

Degraded flight conditions are expected to continue at the TAF
sites from this aftn into Sun aftn, as LIFR/IFR/MVFR CIGs will
prevail, along with occasional showers (isolated thunder). There
may be MVFR or VFR CIGs at ECG through the period, but the other
TAF sites will mainly have IFR or MVFR CIGs. NE or E winds 6-12
kt this aftn, will become SE or S tonight into Sun aftn.

Outlook...Sub-VFR conditions expected at times into Mon, due to
an unsettled weather pattern. Sctd showers and tstms are expected
at all TAF sites Sun aftn through Mon. A warmer, more summerlike
pattern returns Tue through Thu, with chances for storms each
aftn/evening.

&&

.MARINE...
As of 340 PM EDT Saturday...

Key Message:

- Small Craft Advisories remain in effect for the Chesapeake Bay
  and lower James River through late tonight/early Sunday
  morning.

1030mb high pressure is centered over the Gulf of Maine this
aftn, with a stationary front in vicinity of the NC Outer Banks.
The wind is primarily E 10-15kt with guts up to 20kt, and
somewhat less S of Cape Henry in closer proximity to the trough.
Seas are ~4ft, with 3-4ft seas in the mouth of the Ches. Bay,
and 2- 3ft elsewhere in the Ches. Bay. The wind is expected to
increase to 15-20kt with gusts up to 25kt across the Ches. Bay
and lower James later this aftn through the early overnight
hours, before shifting to SE and diminishing slightly later
tonight. SCAs remain in effect for these zones. Seas are
expected to remain ~4ft, with 3-4ft seas in the mouth of the
Ches. Bay, and 2-3ft elsewhere in the Ches. Bay tonight.

The stationary front will lift back N as a warm front Sunday.
with the wind shifting to SE/SSE. A SSW wind returns for Monday
through the middle of next week (but likely remain sub-SCA).
Southerly flow should prevail through most of next week with the
next backdoor cold front possible some time Friday.

&&

.TIDES/COASTAL FLOODING...
As of 340 PM EDT Saturday...

Key Messages:

- The northern Neck remains under a Coastal Flood Advisory
  through Sunday for widespread minor flooding.

- Coastal Flood Statements remain in effect for the bayside of
  the Maryland eastern shore, with an upgrade to a Coastal Flood
  Advisory likely for additional rises late Sunday into Monday
  morning.

Tidal departures remain 1.25-1.5ft above astronomical this
aftn, but have been steady to slowly falling as a decent ebb
tide is occurring. The pattern of an elevated E wind shifting to
the ESE to SE by tonight favors going above ETSS guidance
across the Northern Neck. As such, a Coastal Flood Advisory
remains in effect in this area through Sunday aftn (an extension
through Sunday night/early Monday morning will likely be
needed). A Coastal Flood Statement continues for the bayside of
the MD eastern shore to cover nuisance flooding through late
tonight. Water levels further increase here later Sunday into
early Monday with an upgrade to a Coastal Flood Advisory likely
as a SSE wind will tend to focus the highest departures here by
that time. A Coastal Flood Statement is in effect for locations
on the west shore of the middle Bay to cover nuisance flooding
for the next high tide cycles, but this has not been extended
given the current ebb tide. It still appears that other than
locally moderate flooding at Bishops Head, this event will peak
in minor flood category with the high tide cycle Sunday aftn
into early Monday.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...Coastal Flood Advisory until 4 PM EDT Sunday for VAZ075>078.
MARINE...Small Craft Advisory until 7 AM EDT Sunday for ANZ630>632-634.
     Small Craft Advisory until 4 AM EDT Sunday for ANZ638.

&&

$$

SYNOPSIS...TMG
NEAR TERM...AM/TMG
SHORT TERM...AM/TMG
LONG TERM...AM/TMG
AVIATION...TMG
MARINE...AJZ/LKB
TIDES/COASTAL FLOODING...AKQ