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202
FXUS61 KAKQ 270120
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
920 PM EDT Wed Jun 26 2024

.SYNOPSIS...
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A cold front approaches the area from the northwest, and slowly
crosses the region overnight through Thursday afternoon,
bringing the a chance for showers and thunderstorms. High
pressure builds north of the region late Thursday through the
end of the week.
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&&

.NEAR TERM /UNTIL 8 AM THURSDAY MORNING/...
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As of 900 PM EDT Wednesday...

Key Messages:

- Initial batch of scattered strong/severe storms has pushed
  offshore.

- Additional showers and thunderstorms have redeveloped over the
  far north and will gradually spread south overnight.

- Some beneficial rain has occurred over the north, and
  additional rainfall is likely into at least central portions
  of the area, although it will be hit and miss due to the
  nature of the storms.

The latest analysis shows an upper trough extending south from
the eastern Great Lakes into the TN Valley. The airmass has
stabilized quite a bit over the past few hrs with the loss of
daytime heating (and northern areas having received storms that
dropped temperatures into the low-mid 70s). While elevated
instability remains, along with around 30 kt of effective shear
over the northern 1/2 of the CWA, expect mainly sub-severe
storms overnight. PWATs are rather high at 1.80-1.90" and expect
some training of storms given a WSW low level jet similar to the
flow in the mid/upper levels. Overall, this will be beneficial
rain with the only threat for flooding being if heavy rain
occurs over highly urbanized areas. The 30-35 kt WSW jet will
tend to allow convection to linger through 06-09Z, potentially
into southern VA. Convection gradually diminishes in coverage
early Thu AM. Lows tonight will mainly be in the upper 60s N to
mid 70s SE.
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&&

.SHORT TERM /8 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
As of 255 PM EDT Wednesday...

Key Messages:

- A few thunderstorms are possible across SE VA/NE NC Thursday
afternoon-evening.

- Seasonally hot on both Thursday and Friday.

The cold front slowly pushes south across southern VA and NE NC
Thursday as high pressure and a drier airmass build into the
northern tier of the area. Showers/tstms are expected to redevelop
along the boundary Thursday afternoon with the highest chc across SE
VA and NE NC. However, there is some uncertainty with respect to
where convection develops on Thu (mainly regarding whether it will
be in srn VA/NE NC or just to our south). Coverage/placement of
tstms Thursday aftn will depend on the evolution of overnight
convection. High temperatures return to seasonally hot levels
ranging from the mid 80s to near 90F. Showers/tstms largely
dissipate or move to our south by late Thursday evening,
although some isolated activity could linger into the early
overnight hours over far srn VA/NE NC. High pressure builds
across New England Thursday night into Friday following the
frontal passage. Lows Thursday night fall into the mid 60s-lower
70s. Easterly flow Friday will keep highs in the lower to mid
80s along the coast, and seasonally hot inland with highs in the
upper 80s to around 90F. Surface high pressure initially
settles off the coast Friday night into early Saturday, with
some moisture returning as a weak warm front lifts through the
area. Therefore, there is a slight chc to low chc of showers and
perhaps a tstm from central VA and the Piedmont to the MD
Eastern Shore Friday night into early Saturday morning. Lows
Friday night are mainly in the upper 60s to mid 70s.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
As of 255 PM EDT Wednesday...

Key Messages:

- Heat rebuilds across the region Saturday and Sunday and with more
humidity, with dangerous heat indices likely across parts of the
area on Sunday.

- Scattered showers and thunderstorms are possible later Sunday
afternoon into Sunday night ahead of a cold front.

- A brief break in the heat is likely early next week before very
hot weather potentially returns by Independence Day.

The heat builds back over the local area this weekend as high
pressure settles off the Southeast coast and the low-level flow once
again increases out of the SW. 850mb temps rise to around 20C on
Saturday, and to 20-22C on Sunday. This will support high temps in
the mid 90s both days. Aftn dewpoints will be in the lower to mid
70s (mid 70s mainly toward the coast) during peak heating on both
days. This is supported by the deterministic guidance and MOS
guidance, but is below the mid 70s-80F shown by the NBM (which is
likely too high especially given how dry it has been). Resultant
heat indices are in the 100-105F range on Saturday, and 105-109F for
much of the CWA Sunday. Isolated to widely scattered tstms are
possible on Saturday afternoon (mainly W of I-95), with a better chc
of showers/tstms later Sunday afternoon into Sunday night as the
cold front drops through the region. A slight reprieve in the heat
is likely early next week in the wake of the cold front as the
12z/26 EPS and GEFS continue to depict below average 850mb
temperature anomalies Monday and Tuesday. However, the ensemble
guidance also surges the heat back into the region by the middle of
next week just prior to Independence Day with forecast highs well
into the 90s for much of the area.

&&

.AVIATION /01Z THURSDAY THROUGH MONDAY/...
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As of 900 PM EDT Wednesday...

Initial batch of storms has pushed off the coast of the eastern
shore (SBY had strong winds and LIFR VSBYs but is now back to VFR).
Mainly VFR conditions will prevail through ~04Z, with scattered
showers/tstms mainly expected N of the main terminals, slowly
spreading S overnight. The most likely timing for the next round
of showers/tstms is between 03-06z at RIC/SBY, and from 04-08z
at PHF/ORF. These will mostly be elevated, though a few tstms
could produce strong wind gusts (to 30-40 kt) along with brief
IFR/LIFR flight restrictions in heavy rain. Overall coverage of
showers/tstms diminishes after 08Z/4 AM. Some MVFR stratus is
possible between 08-15z Thursday morning, but CIGs should
otherwise remain VFR through the period.

This front will be slow to push through southern VA and NC NE
Thursday with a 30-50% chc of redeveloping aftn/early evening
showers/tstms (highest at ECG...with lower chances at ORF).
High pressure and dry conditions return Friday into Saturday.
There is another decent chance for showers/tstms later Sunday
into Sunday night.
-- End Changed Discussion --

&&

.MARINE...
As of 130 PM EDT Wednesday...

SW winds mainly 5-15 kt will become S and increase to 10-20 kt with
gusts up to 25 kt by late this aftn into this evening in advance of
a cold front. Waves will build to 2-3 ft in the Bay, and seas will
build to 3-5 ft in the coastal waters. So, SCAs are in effect for
the mouth of the Bay, all coastal waters and the Currituck Sound
from thru 1 AM (4 AM north of Parramore Island). That weakening cold
front will push through the region late tonight into Thu aftn. NE
winds expected late Thu night through Fri morning, then E and SE
winds for Fri aftn into Sat morning, as high pressure slides by to
the north then off the srn New England coast. Low rip current risk
is forecast for all beaches today and Thu. Moderate rip risk on
Friday.

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...Small Craft Advisory until 1 AM EDT Thursday for ANZ633-634-
     654-656-658.
     Small Craft Advisory until 4 AM EDT Thursday for ANZ650-652.

&&

$$

SYNOPSIS...ERI/LKB
NEAR TERM...ERI/LKB
SHORT TERM...AJZ/ERI
LONG TERM...AJZ/ERI
AVIATION...ERI/LKB
MARINE...JDM/TMG