-- Discussion containing changed information from previous version are highlighted. --
163
FXUS61 KAKQ 231752
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
152 PM EDT Sun Jun 23 2024

.SYNOPSIS...
High pressure remains well offshore of the Mid-Atlantic coast
today. A cold front approaches later this afternoon and tonight
from the west, crossing the area early Monday. There is a
chance for showers or storms this evening and Monday, and again
later next week, but many locations will remain dry. Hot
temperatures persist through most of the upcoming week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1015 AM EDT Sunday...

Key Messages:

- Hot today with heat advisory in place for portions of the area.

- Isolated storms in the later afternoon and evening could produce
  strong wind gusts.

The forecast remains largely on track this morning, made a few
updates to account for latest temperature/dewpoint trends. Will
have to watch closely the potential for a few stronger storms
later this afternoon-evening across our western counties. SPC
has placed roughly I-95 and west in a marginal risk for severe
weather with the latest update. Showers/storms will likely try
to form off the higher terrain this afternoon ahead of a cold
front. As noted from earlier, with the best forcing located
north of our local area, would expect storm coverage to be
isolated to scattered at best. Strong to severe wind gusts and
frequent lightning will be the main threats with any stronger
storms today.

Previous Discussion:

The hottest temperatures of the forecast
period are expected today as SSW surface flow strengthens across
the area. This is in response to an approaching cold front and
low pressure to our W/NW and high pressure well offshore. While
there will be upper-level height falls, thickness tools and 850
mb temps of 20-23 C continue to support highs in the upper 90s
for most of the area. Still cannot rule out a few locations
nearing 100 F, but most are expected to fall just short. These
air temps will be very similar to yesterday. However, closer to
the coast, the increased SSW flow will push temps a couple
degrees higher this afternoon. Also am expecting dew points at
least a few degrees warmer than yesterday (upper 60s-low 70s),
which yields heat indices in the 103-108 F range for most of the
area (outside of the very immediate coast). Have therefore
expanded the heat advisory to include the remainder of our SW
counties, NE NC, and Accomack and Northampton Counties on the
eastern shore. Wet bulb globe temperatures (WBGT) will also rise
in the upper 80s areawide, suggesting the potential for
significant heat stress for those outdoors and especially those
performing any strenuous activity. Continue to leave out OBX
Currituck and the MD Beaches from the advisory due to oceanic
influences. The heat advisory is in effect from 11 AM this
morning through 8 PM this evening. Starting the day mostly sunny
with scattered-broken high clouds later this afternoon and
evening.

The other thing to keep an eye on will be any pre-frontal afternoon
or evening convection. With the height falls and moderate sfc-based
instability, could see a few storms develop along and E of the
higher terrain. However, the strongest forcing and associated wind
shear is displaced well N of the area, suggesting only isolated or
widely scattered storms at best. CAMs generally agree with the low
coverage idea, though there is a good deal of spread on where
exactly any storms would develop or move. Have low-end chance PoPs
later this aftn and evening across the W and NW, increasing to 30-
50% for most of the area late this evening and tonight along the
actual front. With plentiful DCAPE, any storm could produce strong
to marginally severe wind gusts (especially this afternoon and
evening). SPC has a marginal risk across the N, with a slight risk
just N of our MD Eastern Shore counties. Aerial QPF will be low and
limited those areas lucky enough to see convection. Lows tonight
will be very mild and in the low-mid 70s (locally upper 70s/around
80 F in the urban corridors and along the coast).

&&

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

Key Messages:

- Remaining hot Monday, though most of the area will fall short
  of heat advisory criteria.

- Scattered to numerous showers and storms possible across far SE VA
  and NE NC on Monday as well.

- Dry weather returns Tuesday with hot conditions persisting.

The front slowly progresses SE early Monday. However, it will slow
or briefly stall over southeastern portions of the area. Along and
ahead of the front, sfc temps in the 90s and dew points in the low-
mid 70s will support plentiful sfc-based instability. In fact, a few
models show pockets of 2500-3000 J/kg of SBCAPE in far SE VA and NE
NC by late morning/early afternoon. While shear remains on the weak
side (~20 kt), this deep instability and continued high DCAPE could
support strong updrafts and damaging downbursts capable of sporadic
wind damage. SPC has newly introduced a marginal risk for svr wx
across the far SE. In terms of PoPs, have the highest (60-70%) over
coastal NE NC and along the Albemarle Sound. Further N and W into SE
VA, there remains some uncertainty on coverage and have 30-50% PoPs.
Most CAMs eventually depict rather aggressive upscale growth of
storms as they slowly push S/SE later in the afternoon. Heavy rain
and frequent lightning also will be likely in any storm. HREF
neighborhood probabilities for 3" in 3 hr are elevated in NE NC but
expect recent dry conditions to mitigate any widespread flash
flooding concerns. Elsewhere, dry conditions are forecast Monday
with highs in the low-mid 90s. Dew points also drop off into the
upper 50s by the afternoon in central VA, so no concerns here in
terms of heat headlines. Also don`t think a heat advisory will be
needed across the SE as the aforementioned convection may put an
early end to the heat/humidity. More relief expected Mon night with
lower humidity and lows in the low-mid 60s.

Weak high pressure will settle near the area behind the front for
Tuesday. Expecting dry wx all areas with very comfortable humidity
levels. Still, it will remain on the hot side with afternoon highs
in the low 90s inland and upper 80s at the coast. Lows Tue night in
the upper 60s-lower 70s.

&&

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

Key Messages:

- The hottest day in the extended period is Wednesday with high
  temperatures in the mid to upper 90s.

- Scattered showers and storms possible with a cold front Thursday.

- Flash drought conditions developing across most of the area.

The hot weather returns again for Wednesday and we again could be
talking about temps nearing 100 F, though the latest NBM remains a
few degrees shy of triple digits. Heat indices look to be kept in
check (~100 F at most) due to lower afternoon humidity levels. An
isolated storm or two could also spill into our western or northern
counties, especially later in the day. By Wednesday night and
Thursday, another cold front approaches from the NW. The 00z global
model suite is not enthusiastic about widespread rainfall from this
front (being cut off from most of the deeper Gulf of Mexico
moisture) and generally keeps a good portion of the area dry.
Probabilities of >0.50" from the NBM are only 20-40% across the area
and highest in srn VA and NE NC. Will keep the highest PoPs across
the SE where the FROPA looks to occur with the afternoon daytime
heating window. The heat is expected to build again to end the week
and into next weekend as GEFS/EPS runs show an upper-level dome of
high pressure (594+ dm) expanding across much of the S-central and
SE CONUS. Highs Thursday and Friday in the low-mid 90s, with mid-
upper 90s potentially returning for the weekend. Overnight lows
generally in the upper 60s or lower 70s through the extended period.

The upcoming dry conditions will only exacerbate the recent dry
spell and it looks to set us up for what is considered a "flash
drought". More information on this can be found on CPC`s
Probabilistic Hazards Outlook page at www.ncep.cpc.noaa.gov or
drought.gov.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
As of 250 PM EDT Sunday...

A cold front approaches the region from the northwest late this
afternoon through tonight, bringing increasing cloud cover and
increasing chances for mainly scattered showers and
thunderstorms. Primarily VFR conditions are anticipated through
the period outside of any convection. Gusty SSW winds this
afternoon through this evening, with gusts of 20-25 knots.
Slightly higher rain chances after 06z, especially across the
east and southeast. Some MVFR CIGs will be possible at the
eastern TAF sites as we approach sunrise. Scattered chances for
showers and storms return late Monday morning into Monday
afternoon, mainly focused along coastal terminals with some
localized sub-VFR conditions possible. Winds flip around to the
NW Monday morning into Monday afternoon in the wake of the
front.

Outlook: Prevailing VFR flying conditions are expected Monday
night through midweek.
-- End Changed Discussion --

&&

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

Key Messages:

- SCAs are in effect for the entire marine area. Today into
  tonight for the Ches. Bay and this afternoon into tonight for
  the remainder of the marine area.

- Benign marine conditions expected for the early to mid week
  period.

- Moderate Rip Current Risk continues today.

High pressure is centered well off the Southeast coast
early this morning. Meanwhile, low pressure is centered over the
northern Great Lakes with a cold front trailing back through the
Midwest. The wind is primarily SSW 10-15kt early this morning with
occasionally up to 15-20kt for the middle Ches. Bay and northern
ocean zones. Seas range from 2-3ft S to 3-4ft N with waves in the
Ches. Bay ~2ft. Low pressure tracks well N of the region today into
tonight, with the weakening cold front approaching from the NW today
and then settling into the area tonight. A SSW wind will initially
remain 10-15kt with gusts up to 20kt through midday, before
increasing to 15-25kt later this aftn into tonight (20-25kt over the
ocean and Ches. Bay this evening) as a 35-45kt LLJ passes across the
region in advance of the cold front. Minimal gustiness is expected
outside of any tstms as a very warm airmass advects over relatively
cool water. Seas build to 4-5ft S to 5-7ft N later this aftn into
tonight. SCAs for the Ches. Bay go into effect at 4 AM, with the
remaining zones going into effect at 1 PM, with SCAs stepping down
later tonight into Monday morning (latest for the ocean where seas
will be slow to subside).

The cold front pushes offshore Monday into Monday night as weak high
pressure builds in from the N. The wind will shift to NW 10-15kt
across the northern tier of the area Monday. In vicinity of the
coasts of SE VA/NE NC, the wind will initially be WSW early Monday,
and then become light and locally variable in the aftn as the front
stalls. By Monday night, the wind becomes NNW 10-15kt for most of
the marine area. The front washes out in vicinity of the Carolina
coastal plain Tuesday with very weak flow expected. High pressure
rebuilds offshore by the middle of the week with sub-SCA southerly
flow returning. Seas will mainly be 2-3ft Monday night into the
middle of the week with 1-2ft waves in the Ches. Bay. Another
weakening cold front pushes through the region Thursday into
Thursday night. An increase in a SSW wind is possible ahead of the
cold front Wednesday night along with seas/waves building to 3-4ft
N/2-3ft. Marginal SCA conditions are possible, primarily in the Ches.
Bay.

Rip currents: A moderate rip risk will continue today. However, an
increasing SSW wind will likely lead to a longshore current and
building nearshore waves, especially for the northern beaches.

&&

.CLIMATE...
Record high minimum temperatures for today (Sunday, June 23):

- RIC: 76 (2010)
- ORF: 79 (2015)
- SBY: 75 (1925)
- ECG: 78 (2015)

Record high temperatures for today (Sunday, June 23):

- RIC: 101 (1988)
- ORF: 99 (2015)
- SBY: 99 (1988)
- ECG: 99 (2011)

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Heat Advisory until 8 PM EDT this evening for MDZ021>024.
NC...Heat Advisory until 8 PM EDT this evening for NCZ012>017-
     030>032.
VA...Heat Advisory until 8 PM EDT this evening for VAZ048-060>062-
     064>069-075>090-092-093-095>100-509>525.
MARINE...Small Craft Advisory until 4 AM EDT Monday for ANZ630>634-638.
     Small Craft Advisory until 1 AM EDT Monday for ANZ635>637.
     Small Craft Advisory until 10 AM EDT Monday for ANZ650-652-654-
     656-658.
-- End Changed Discussion --

&&

$$

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