525
FXUS61 KAKQ 180612
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
212 AM EDT Thu Jul 18 2024

.SYNOPSIS...
Showers and storms continue today as a cold front slowly pushes
through the area. Showers diminish tonight as the front moves
south, then focus mainly over southern Virginia and North
Carolina Friday. The front lifts back north, bringing unsettled
conditions back to most of the area on Saturday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 200 AM EDT Thursday...

Key Messages:

- Showers/storms now across NE NC, continue to push south,
  diminishing towards sunrise.

Showers/storms gradually diminish by or shortly after midnight,
with lingering showers and embedded storms possible overnight
(but with little SVR threat). Lows in the lower 70s NW to the
mid-upper 70s SE.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH SATURDAY/...
As of 300 PM EDT Wednesday...

Key Messages:

- There is a heavy rain threat Thursday across portions of southeast
Virginia into northeast North Carolina where WPC has a Slight Risk
of excessive rainfall.

- There is a Marginal Risk of severe weather roughly along and south
of US-460 Thursday.

On Thursday, PoPs ramp back up in the mid/late morning as the actual
cold front pushes into the region, gradually moving south through
the day Thursday, before eventually stalling near the NC/VA border
Thursday night. Highest shower/storm chances will be focused across
the southern half of the area on Thursday. Locally heavy rainfall
will be possible, with a Day 2 Slight Risk ERO for far southern
Virginia and northeast North Carolina where much of the guidance is
forecasting in excess of 2" of QPF. The 12z HREF probability matched
means now have a large 50% contour for 3"/3hr centered over SE VA
into NE NC tomorrow afternoon/evening, with even a small 70% contour
over portions of NE NC. Based on the current trends, it is very
possible a Flood Watch will be needed for at least southside Hampton
Roads into northeast North Carolina, will let the overnight shift
make the final determination. There is a Marginal ERO for the
remainder of the forecast area, but expect shower to diminish in
coverage and intensity.  chance for showers/tstms is less
Friday (except over far SE VA/NE NC) and then increases again
Saturday over the north by the late afternoon.

Will also need to watch the severe weather potential on Thursday
afternoon with a few of the CAMs being quite aggressive. There will
again be plenty of instability tomorrow, with ~2000 to 3000 J/kg of
MLCAPE in place across the region despite the clouds. We will also
have more effective shear over the area compared to today, with 30-
40 knots possible. The primary hazard tomorrow with any stronger
storms will again be damaging wind gusts, with the hail threat
remaining limited due to weak mid-level lapse rates. If we can fully
destabilize, as some of the CAMs have been showing, there is
the potential for a corridor of greater damaging wind potential.
For now, SPC has roughly along and south of US-460 in a
Marginal Risk for severe weather.

The front pushes just south of the local area Thursday night into
Friday, with the highest rain chances confined to the southern
areas. With some clearing and drier air/lower dew pts, lows Thu
night drop into the low-mid 60s NW, with lower 70s SE (where its
stays humid with more clouds). Drying out for the northern half of
the area Friday, with only scattered shower and storm chances by
Friday afternoon (over the south). Partly sunny N and mostly cloudy
S with high temperatures mainly in the low-mid 80s (more comfortable
N and central where dew pts will be in the 60s).

The upper trough moving into New England looks to flatten out later
Friday while the area of high pressure off the Southeast coast
begins to gradually retrograde back westward slightly. The front is
forecast to lift back north into the southeastern portion of the
area and stall out into Saturday. The best rain chances Friday night
will be across northeast North Carolina in the vicinity of the
boundary, then chances spread back north on Saturday as the front
shifts. The higher rain/storm chances on Saturday will be south of
the I-64 corridor.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 300 PM EDT Wednesday...

Key Messages:

- Daily rain chances persist as the front lifts back north and
stalls over the southeastern portion of the area.

- Temperatures look to stay near normal.

A positively tilted trough will start to dip down into the mid
Mississippi Valley on Sunday allowing our flow to become more
southwesterly. The stalled front won`t move very much, but it does
become a bit more diffuse on Sunday so generally should see rain
chances focus in the aftn/evening rather than all day. Variable
cloudy and a bit warmer with highs in the mid 80s to around 90F.
Remaining a bit unsettled into early next week, with the southern
and western portions of the area having the best chance for
rain/storms. After a brief, partial break from the humidity
(especially up north), 70+ degree dewpoints will stream back into
the area for this forecast period making it feel humid once again.
The somewhat good news is that temperatures aren`t expected to be
nearly as hot during the extended period as they have been, with
high temperatures Mon-Tue forecast to top out in the mid to upper
80s to near 90F, which is right around or even slightly below normal
for this time of year.

&&

.AVIATION /06Z THURSDAY THROUGH MONDAY/...
As of 200 AM EDT Thursday...

Showers and thunderstorms continue in NE NC early this morning
with IFR flight restrictions for a few hrs at ECG, mainly VFR
with light rain across southern VA but tstms have ended. Some
MVFR-IFR CIGs may affect the terminals towards sunrise but
confidence is low. Just a few showers for most of the rest of
the morning, then showers and tstms become more widespread by
early aftn, with flight restrictions likely in heavy rain.
Strong gusty winds will also be possible in the storms,
especially across southern VA and NE NC between ~18Z and ~00Z.

Outlook: The front will push farther S tonight as drier air
pushes in from the NW, with some local IFR-MVFR restrictions
still possible at ORF/PHF/ECG, mainly VFR to the north. Mainly
VFR/dry Friday over the north and central, with flight
restrictions possible mainly for ECG. The boundary lifts back N
Saturday with showers and tstms scattered to likely for most
areas. Sunday will see scattered, mainly aftn/evening
showers/storms.

&&

.MARINE...
As of 300 PM EDT Wednesday...

Key Messages:

- Small craft advisories in effect for the Chesapeake Bay and
northern coastal waters this evening into early tonight. A severe
thunderstorm watch is also in effect for the upper bay and northern
coastal waters through 10 PM.

- Additional showers and storms expected Thursday.

- Calmer marine conditions return Friday through the weekend.

Bermuda high pressure is situated well offshore this afternoon,
leading to SW flow across all of the waters. A cold front is also
located well to our NW, extending from the nrn Great Lakes into the
Mid MS River Valley. Winds are averaging around 15 kt, though a few
sites are in the 15-20 kt range. With a tightening pressure gradient
and convection approaching from the W, winds are forecast to
increase to 15-20 kt areawide this evening into tonight, with gusts
to ~25 kt. This will also push seas in the northern waters to 4-5 ft
(6 ft possible out near 20 nm). Have continued SCA headlines for the
ocean N of Cape Charles and introduced new SCAs for the Chesapeake
Bay starting at 4 PM this afternoon. While the duration of these
winds are uncertain, local wind probabilities are >50% for 18 kt
sustained winds and 25 kt gusts for most of the central/upper bay.
Waves of 2-3 ft are also expected. For now, the SCA goes through 10
PM over the bay and through most of tonight for the northern coastal
waters. S of Cape Charles, seas look to stay below 5 ft and wind
gusts should remain just shy of 25 kt; thus, continue to hold off on
SCAs here. Later this evening, convection may complicate these
prevailing winds and there is the potential for strong-severe wind
gusts of 40-50+ kts. A severe thunderstorm watch is also in effect
for the upper bay zone (ANZ630) through 10 PM. Winds subside around
sunrise Thursday as the gradient slackens and the cold front begins
to enter our area. The front then briefly stalls over the waters Thu
afternoon, allowing winds to begin rather variable. This front will
also serve as a focus for widespread showers and storms, especially
across the the srn bay and coastal waters. Strong to severe wind
gusts are again a possibility, in addition to heavy rain and
frequent lightning. ~10 kt of E/NE flow is expected Friday, shifting
to the SE Saturday. Seas and waves of 2-3 ft and 1-2 ft are expected
beyond Thursday, respectively.

With the southerly flow and 3-4 ft nearshore waves, the rip risk
remains moderate for the northern beaches today and at least for the
first half of the day Thursday. A low risk is forecast through today
and Thursday across southern beaches. Note that continued S/SW flow
may exacerbate upwelling conditions, leading to much cooler-than-
expected water temperatures (low-mid 60s) in the surf zone.

&&

.CLIMATE...
A record high min temperature was tied yesterday/Tue 7/16 at
SBY. Records are listed below for today/Wed 7/17. Record highs
are unlikely and although record high mins may be challenged,
showers and storms late in the day/tonight may lead to calendar
date mins lower than what is observed this morning.

- Record Highs:

- Site:  Wed 7/17

- RIC:   100 (1980)
- ORF:   100 (1887)
- SBY:    99 (2012)
- ECG:    99 (1942)

- Record High Mins:

- Site:   Wed 7/17

- RIC:    76 (2005)
- ORF:    80 (2021)
- SBY:    80 (1983)
- ECG:    80 (2019)

- Highest 1-hr Heat Index Value on record (P.O.R. 1948-2024):

- RIC:   117 (7/17/1980)
- ORF:   118 (8/18/2017)
- SBY:   122 (7/15/1995)
- ECG:   119 (7/5/1999)

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 7 AM EDT this morning for ANZ650-
     652.

&&

$$

SYNOPSIS...LKB
NEAR TERM...AJB
SHORT TERM...AJB/LKB
LONG TERM...AJB/LKB
AVIATION...AJB/LKB
MARINE...SW
CLIMATE...