759
FXUS61 KAKQ 170718
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
318 AM EDT Wed Jul 17 2024

.SYNOPSIS...
Hot and humid conditions prevail through this afternoon ahead of
a cold front. An unsettled period begins late this afternoon
through Thursday, as a cold front pushes through the area and
stalls across the Carolinas. Shower chances focus mainly over
southern Virginia and North Carolina Friday, then return to all
zones by Saturday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 800 PM EDT Tuesday...

Key Messages:

- Excessive Heat Warnings and Heat Advisories have been allowed
  to expire at 8 PM.

- There is a Marginal Risk of severe weather late this afternoon
through this evening for much of the area. Damaging wind gusts are
the main threat with any stronger storms.

Similar to the past couple of days, Bermuda high pressure remains
anchored well offshore with a surface trough just east of the Blue
Ridge mountains. Warm 850mb temps have resulted in a bit of
capping across the area with showers and storms struggling.
There are two zones that may still see isolated showers/storms,
the NW Piedmont (from storms moving off the Blue Ridge) and NE
NC (from storms in N central NC moving NE). Neither looks
particularly robust at the moment. However, given favorable CAPE
in NC NC and DCAPE across the NW Piedmont, gusty winds will be
possible. SPC has much of the northern and western portions of
the area highlighted in a Day 1 Marginal Risk for severe
weather. Any shower/storm chances come to an end later this
evening, with partly cloudy skies overnight. Temps as of 8 PM
ranged from the upper 80s to around 90F across the area. Temperatures
remain warm tonight with lows only falling back into the mid
70s to upper 70s (around 80 in the urban areas and along the
coast). Location such as Norfolk may not get below 80F overnight
given SSW winds remaining breezy through the night with gusts up
to 20-25 mph possible.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH FRIDAY/...
As of 330 PM EDT Tuesday...

Key Messages:

- Remaining hot Wednesday and humid area-wide but with a higher
coverage of storms by afternoon. Heat Advisories are in effect for
the entire area with the exception of the MD beaches.

- Showers/storms become fairly widespread late Wednesday/Wednesday
night through Thursday.

- There is a Slight Risk for severe weather across the northern
  half of the forecast area Wednesday, with a Marginal Risk
  elsewhere.

Better forcing tomorrow as a cold front begins to approach from the
northwest and the strong upper ridge over the region begins to break
down. Latest CAMs for tomorrow have storms beginning to fire late
morning into the early afternoon along a lee trough just east of the
Blue Ridge mountains, becoming more widespread and advancing further
east later tomorrow afternoon through the evening hours. Even though
mid level lapse rates are on the weaker side tomorrow and bulk shear
will only be on the order of ~20 to 30 knots (greater than we have
seen as of late), we will have plenty of instability over the region
with MLCAPE climbing in excess of 2000 J/kg by tomorrow afternoon.
Storms will primarily be mainly be linear clusters, but a marginal
supercell or two cannot be ruled out. The main threat with the
strongest storms tomorrow will be damaging wind gusts. SPC has
highlighted the northern half of the forecast area in a Slight Risk
for severe weather and a Marginal Risk elsewhere. In addition to the
severe weather threat, there will also be a localized heavy rain
threat as moisture pools ahead of the front, and PWATs surge to
2.25+".

It will also be one more hot day tomorrow, with temperatures
climbing into the mid to upper 90s combined with dewpoints in the
mid to upper 70s, making it feel like 105-109 degrees. A few
locations may approach or exceed 110F+, but lower confidence
tomorrow compared to today, especially with more cloud cover and
increasing shower/storm chances. All of the area has been included
in a Heat Advisory for tomorrow with the only exception being the MD
beaches.

The cold front gradually pushes south through the region Wednesday
night and 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. There is a
Marginal ERO for the remainder of the forecast area. Widespread
clouds and rain on Thursday will keep temperatures in the 80s. The
front pushes just south of the local area Thursday night into
Friday, with the highest rain chances confined to the southern
areas. Drying out for the northern half of the area Friday, with
only scattered shower and storm chances by Friday afternoon. High
temperatures will again be in the 80s.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
As of 300 PM EDT Tuesday...

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.

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. 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,
so rain chances look to remain fairly similar into early next week,
with the southern half 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 forecast to top out in the mid to upper 80s, which
is right around or even slightly below normal for this time of year.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
As of 200 AM EDT Wednesday...

VFR conditions prevail into this aftn ahead of an approaching
cold front, with SSW winds ~10kt, increasing to 10-15kt with
gusts to 20-25kt by late morning. SCT-BKN cumulus develops
during the aftn. Scattered showers and storms will mainly be W
of the terminals until late in the aftn, will have mention of
VCTS starting in the 20-23Z timeframe, with prevailing SHRA at
all but ECG 23-01Z and thereafter into tonight. Gusty winds and
heavy rain will be possible with any storms, with IFR-LIFR
flight restrictions in VSBY. Gusty winds in excess of 40kt will
be possible in the storms as well, especially at RIC/SBY.
Showers and storms taper off from W to E later tonight as
forcing weakens.

Outlook: The cold front lags back to the NW into Thu morning,
then pushes S through the FA on Thu with scattered to numerous showers
and storms redeveloping. Thunder chances decrease across
northern areas by later in the day, becoming more focused across
southern VA and NC. Periodic flight restrictions (mainly VSBYs) are
expected due to locally heavy rain along with gusty winds. The
front will push farther S Thu night into Friday as drier air
pushes in from the NW. The boundary lifts back N Saturday. The
chance for showers/tstms is less Friday (except over far SE
VA/NE NC) and then increases again Saturday. Sunday will see
scattered, mainly aftn/evening showers/storms.

&&

.MARINE...
As of 315 PM EDT Tuesday...

Key Messages:

- Small Craft Advisories are in effect for the Chesapeake Bay and
  lower James River this morning.

- Winds and seas increase again this evening with SCA conditions likely
  in the Chesapeake Bay as well as the Atlantic waters north of
  Cape Charles Light.

Bermuda high pressure remains dominant offshore with a lee
trough over inland areas. The gradient between these features
has tightened enough to justify marginal SCA headlines in the
Ches Bay as well as the lower James River this morning with SW
winds 15-20 kt and a few gusts to 25 kt. Winds are expected to
fall back to 10-15 kt by mid morning. The surface trough will
sharpen this afternoon with the potential for increased coverage
of showers and storms into this evening. Will hold off on
additional headlines for the bay/James for now but a period of
SW 15-20 kt winds is likely late this afternoon into the
overnight hours. Confidence in seeing 4-6 ft seas in the
northern coastal waters has increased enough to hoist SCA
headlines from this afternoon into early Thursday. Elevated seas
should be rather short-lived with seas averaging 2-4 ft from
late Thursday morning through early next week. Guidance
continues to slow the frontal passage across the region Thursday
with additional showers and storms likely south of the boundary
Thursday afternoon. Still think the front will move south of
the waters on Friday with N or NE winds 5-10 kt behind the
boundary. Sub-SCA winds/waves/seas look to persist well into
next week.

A moderate rip current risk is forecast today and tomorrow for the
northern beaches (including Ocean City). Low rip risk today and
Thursday for VA Beach into the northern NC OBX.

&&

.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...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for MDZ021>024.
NC...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for NCZ012>017-030>032-102.
VA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for VAZ048-060>062-064>069-075>090-092-093-095>100-
     509>525.
MARINE...Small Craft Advisory until 7 AM EDT this morning for ANZ630.
     Small Craft Advisory until 10 AM EDT this morning for ANZ631-
     632-634-638.
     Small Craft Advisory from 4 PM this afternoon to 7 AM EDT
     Thursday for ANZ650-652.
     Small Craft Advisory from 4 PM this afternoon to 4 AM EDT
     Thursday for ANZ654.

&&

$$

SYNOPSIS...LKB
NEAR TERM...AJB/RMM
SHORT TERM...AJB/LKB
LONG TERM...LKB/JKP
AVIATION...LKB
MARINE...RHR
CLIMATE...AKQ