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496
FXUS61 KAKQ 230529
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
129 AM EDT Sun Jun 23 2024

.SYNOPSIS...
High pressure off slides further off the Mid Atlantic coast
tonight into Sunday as a weak cold front approaches from the
northwest. There is a small chance for rain Sunday evening into
Monday, and again later next week, but most locations will
remain dry. Hot temperatures return by the middle of next week.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 925 PM EDT Saturday...

Key Message:

- Remaining warm overnight with lows in the 70s, upper 70s to
  near 80 in urban centers and along the coast.

Early evening analysis reveals ~1024mb sfc high pressure now
well offshore of the mid-Atlantic coast over Bermuda, with a
weak surface trough extending from E PA SSW into the VA/NC
piedmont. Aloft, upper level ridging centered over the southern
plains into the mid-south covers much of the southern half of
the CONUS, nudging into the lower mid-Atlantic region.

No major changes to the going forecast needed. Mainly clear for
much of the overnight with some low stratus/patchy fog possible
once again along the Albemarle Sound late tonight/early Sunday.
Lows tonight will not provide a ton of relief and only drop
into the mid 70s inland and upper 70s to around 80 along the
bay/ocean and over urban centers. Lows tonight may challenge
record high minimum temperatures in spots. Please see the
climate section below for more details.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH TUESDAY/...
As of 300 PM EDT Saturday...

Key Messages:

- Another hot day on Sunday with maximum temperatures in the
  mid/upper 90s to around 100 F. Another round of Heat
  Advisories are in effect for much of hour area, with the
  exception of our NC counties, VA eastern shore and far SW
  piedmont counties.

- Isolated to widely scattered storms possible later Sunday
  through Monday afternoon.

- Drier and not quite as hot for Tuesday.

The core of the heat is expected to shift E/SE some for Sunday,
though hot temps will remain over the entire forecast area.
High temperatures will be similar to today. Highs range from the
mid to upper 90s for most of the area to around 100 F in the
urban corridor within and surrounding Richmond. Clouds increase
some later in the day across the NW so something to keep an eye
on there. Guidance continues to advertise higher dew points
Sunday due to strengthening southwesterly sfc flow. Soundings
still show more moisture at and above the surface. This would
lead to higher levels of humidity and thus heat indices in the
afternoon. The current forecast has heat indices between 103 and
106 F, with the highest values focused around the Richmond
Metro into eastern Virginia and including portions of the
Maryland Eastern Shore. Wet bulb global temperatures (WBGT) in
the upper 80s to around 90 suggest the potential for significant
heat stress for those outdoors and especially those
participating in strenuous activities. Heat Advisories are in
effect for the same locations on Sunday as today, with the
addition of the Maryland Eastern Shore. May need to add
northeast NC into the the Advisory as well, but will let later
shifts take a final look. We should have enough mixing across
our SW counties to keep heat index values "only" around 100 F.
There again will not be much relief from the heat Sunday night
with lows in the mid to upper 70s.

Isolated to widely scattered showers and storms are still a
possibility Sunday afternoon and especially in the evening and
overnight hours ahead of a weak cold front. Also expecting a weak
sfc trough to set up east of the mountains. As is typically the
case, the NAM is most aggressive regarding convective coverage and
intensity. This could be related the model being slightly more
amplified and having higher dew points. SPC continues the marginal
risk for the northern third of the area. This makes sense as shear
is higher with northern extent (though it only peaks at ~20 kt).
Overall, this suggests loosely organized storms capable of strong to
marginally severe wind gusts given steep low-level lapse rates and
high DCAPE. PoPs are 20-30% in the afternoon, increasing to 30-60%
(highest N and NE) in the evening and early overnight period. Chance
PoPs linger through most of the night with the boundary nearby.
Still, this does not look to be a widespread beneficial rainfall to
alleviate the developing drought over the area, with only ~0.10-
0.20" of QPF in the forecast for portions of the area through Sunday
night.

The front will be located across the SE Monday and have kept the
trend going from previous forecasts with the best chances for
showers and storms further SE. If current trends in the guidance
continue, it may stay dry for most of the area, outside of far SE VA
and NE NC. There will be ample instability along and ahead of the
front so any storm again will be capable of producing strong to
marginally severe wind gusts, in addition to frequent lightning and
heavy rain. It also continues to look hot with high temps in the low-
mid 90s. The highest dew points will reside across the SE VA and NE
NC and heat indices of around 105 F are expected for those
locations. The one caveat is storms could initiate as early as late
morning or early afternoon in these areas given the
moist/hot/unstable airmass, potentially preventing the high-end temp
potential from being realized. Overnight lows in the mid-upper 60s
inland and lower 70s closer to the coast.

Slightly cooler Tuesday with highs ranging from the mid to upper 80s
along the coast to the lower 90s inland. It will feel noticeably
less humid with dewpoints dipping back into the lower 60s and upper
50s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
As of 300 PM EDT Saturday...

Key Messages:

- The heat builds again midweek, with temperatures climbing back
  well into the 90s once again.

- 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 is a degree
or two shy of triple digits. Heat indices increase to 100-105 F, but
this is again dependent on the degree of BL mixing in the afternoon.
An isolated storm or two could also spill into our western counties.
By Wednesday night and Thursday, another cold front approaches from
the NW and will continue chance PoPs for the area. Widespread
rainfall is not expected with this feature and probabilities of such
remain quite low through the extended period. Guidance is warmer in
the late week period and most areas may stay in the lower 90s.

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 /06Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
As of 130 AM EDT Sunday...

Prevailing VFR across area terminals looks to persist through
the 06z TAF period. Only sky cover to deal with early this
morning will be thin, high clouds. There is a low chance of
brief MVFR CIGs or VSBY at ECG around sunrise, but confidence is
too low for a prevailing group of this. SSW winds average 8-13
kt through ~12z, becoming gusty to ~20-25 kt by late morning and
the afternoon. Gusty winds last into this evening and tonight.
Depending on any low- level inversions, cannot rule out some
low-level wind shear tonight. There is also low chance for some
isolated to widely scattered storms Sunday evening, with perhaps
some better coverage of showers in the 06-12z timeframe Monday.

Outlook: Isolated to widely scattered chances for showers and
storms return on Monday afternoon into Monday evening, mainly
focused along coastal terminals with some localized sub- VFR
conditions possible. Otherwise, prevailing VFR flying conditions
are expected through early next week.
-- End Changed Discussion --

&&

.MARINE...
As of 925 PM EDT Saturday...

Key Messages:

- SCAs have been raised for the bay starting early Sunday morning
for elevated southerly winds. SCAs start for the coastal waters,
lower James, and Currituck Sound Sunday afternoon.

- Benign marine conditions expected for the early week period.

- Moderate Rip Current Risk continues through tomorrow.

Winds over the upper Bay and northern coastal waters are 15 to
20 kt this evening and may decrease briefly later tonight before
increasing again by daybreak. This increase in winds this
evening was expected and a couple of hours with gusts around
20kt in the bay will persist. Winds will increase during the
early morning hours (before sunrise) as a weak front approaches.
SCAs have been raised for the bay starting at 4am for gusts up
to 25kt. The front approaches the region Sunday and crosses
local waters early Monday morning. Elevated S/SW winds are
expected as the pressure gradient tightens between the front and
high pressure offshore and the LLJ increases to 30-40kt. Winds
will be 15-20kt (highest in N coastal waters) Sun morning
through early afternoon. Through the rest of the afternoon and
into the overnight hours, the rivers and bay will stay in the
15-20kt (gusts to 25kt) range, but winds over coastal waters
pick up to 20-25kt (gusts around 30kt). SCAs for the coastal
waters, lower James, and Currituck Sound will go into effect
early Sunday afternoon. Will let the night shift evaluate the
need for SCAs on the remaining river zones given marginal nature
there.

Lighter winds are expected behind the front as they turn to the NW.
Winds will be around 10kt Monday with a sea breeze likely to form in
the afternoon, especially at along the southern coast line (VA Beach
and south). High pressure slides overhead Tuesday, which will lead
to some variation in wind direction through the morning, but will
generally be onshore (10kt or less) by the afternoon. May see
another round of increased winds ahead of a front mid-week, but
looks to be sub-SCA for now.

Seas are around 3ft this afternoon and will increase to 3-4ft later
this evening. As winds increase Sunday evening, seas will increase to
5-6ft in northern waters and 4-5ft in southern. Seas diminish
through the day Monday, falling back to 2-3ft by the evening. Waves
are 1-2ft this afternoon. Waves will pick up to 2-3ft this evening
and remain there through early Monday.

Rips: A moderate rip current risk will continue through Sunday.
Confidence is of moderate is higher for the northern beaches Sunday,
but southerly flow and a longshore current may preclude a high risk.

&&

.CLIMATE...
Record high temperatures for today, Saturday, June 22 w/actual highs:

- RIC: 101 (1933) (Actual high 99)
- ORF: 99 (1981)  (97)
- SBY: 98 (1988)  (96)
- ECG: 98 (1942)  (93)

Record high minimum temperatures for Sunday, June 23:

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

Record high temperatures for Sunday, June 23:

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

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
MD...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for MDZ021>024.
NC...None.
VA...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for VAZ048-061-062-064-068-069-075>078-080>086-088>090-
     092-093-095>098-509>525.
MARINE...Small Craft Advisory until 4 AM EDT Monday for ANZ630>632-634.
     Small Craft Advisory from 1 PM this afternoon to 4 AM EDT
     Monday for ANZ633-638.
     Small Craft Advisory from 1 PM this afternoon to 10 AM EDT
     Monday for ANZ650-652-654-656-658.
-- End Changed Discussion --

&&

$$

SYNOPSIS...AJB/SW
NEAR TERM...AJB/MAM
SHORT TERM...AJB/SW
LONG TERM...AJB/SW
AVIATION...SW
MARINE...AM/JAO
CLIMATE...