-- Discussion containing changed information from previous version are highlighted. --
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FXUS61 KAKQ 210515
AFDAKQ

AREA FORECAST DISCUSSION
National Weather Service Wakefield VA
115 AM EDT Fri Jun 21 2024

.SYNOPSIS...
High pressure off the Mid Atlantic coast slowly shifts south
through the end of the week leading to an extended period of
hot weather this weekend and continues into next week. There is
a small chance for rain Sunday night into Monday, and again on
Thursday, but many places will stay dry.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
As of 950 PM EDT Thursday...

Key Message:

- Quiet and seasonable tonight.

High pressure offshore will allow for continued dry conditions
with mostly clear skies overnight. Temps as of 945 PM were
generally in the low-mid 70s with dew points in the mid 60s.
Guidance suggests dew points may creep up into the mid- upper
60s tonight (higher close to the coast), so low temperatures may
be slightly warmer than last night. Lows will likely range from
the mid to upper 60s which is seasonable for this time of year.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
As of 230 PM EDT Thursday...

Key Messages:

- Turning warmer and a little more humid for Friday.

- Hot conditions expected Saturday and Sunday with maximum
  temperatures approaching 100F

- Heat index values 105F or greater Sunday.

Very little change to the current forecast for Friday into
Sunday. Expecting the heat to start on Friday as the sfc/upper
ridge axis shifts south of the area allowing warmer 850mb temps
over the Ohio Valley to move southward. Warmest readings on
Friday will be across the north and west where winds will turn S
or SW. Areas closer to the coast and across the southeast will
be a little cooler with winds staying more SE. Will continue
with mid 90s in central VA and the Piedmont, with upper 80s to
lower 90s in SE VA/NC NC and areas close to the coast.

The core of the heat will move over the region Saturday and
especially Sunday. Guidance is quite similar to the previous
runs showing +23C 850mb temps over the area Sat and Sun
afternoon. This, combined with S-SW winds will allow temps to
rise to close to 100 F across central VA on Saturday with mid to
upper 90s elsewhere. This will allow heat index values to rise
to 100-104 with the warmest in central VA. Luckily dew points
are expected to mix out into the mid 60s Saturday afternoon so
we are not expecting heat index values to be too extreme.

On Sunday, temperatures may rise a degree or two with more
places likely above 100F especially in central VA. In fact, the
NBM shows about an 80 percent probability of temperature AOA
100F on Sunday across central VA, as compared to 50-70% prob on
Saturday. This should lead to heat index values to rise to
105-109 range which would be well into heat advisory criteria.
Regardless of the exact heat index values, all areas need to be
prepared for an dangerous heat through the weekend.

SE VA and NE NC may stay slightly cooler with regards to
temperatures for the weekend. However, these areas will have
slightly higher dew points. As such, the effective heat index
will be similar on Saturday and Sunday.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
As of 230 PM EDT Thursday...

Key Messages:

- Slightly lower temperatures on Monday, but more humid, leading
  to another day of 100+ heat index values.

- A weakening frontal system may bring isolated to widely scattered
showers or storms on Sunday night into Tuesday, but the confidence
in widespread rainfall remains low.

- Flash Drought conditions developing.

- Temperatures in the upper 90s to near 100 possible again on
  Wednesday before another front approaches on Thursday.

Models continue to struggle with any precipitation on Monday.
Although we will keep chances for showers and storms on Sunday
night into Monday, many places will remain dry. Best chances for
storms on Monday will be closer to the coast, but have still
limited to chance PoPs. Most of the deterministic models have
areas west of I-95 completely dry on Sun night and Monday.
Temperatures on Monday will be highly dependent on cloud cover
and any rainfall. With this in mind, have kept the warmest
temps west of I-95 where the precip chances are least with the
forecast in the mid 90s. Low to mid 90s closer to the coast but
it will be more humid so the highest heat index readings of 100
or greater will likely be in eastern VA and NE NC.

Main change to the extended was to ultimately increase
temperatures for Tue and especially Wed. Latest NBM guidance
suggests temperatures will be in the low to mid 90s on Tuesday
despite the cold front passage. This ultimately makes sense
given the downslope NW flow and still warm 850mb temps around
+21c per the GFS. It will be drier, however, with dew points
perhaps dropping back in the mid 60s as compared to the upper
60s/low 70s on Monday.

By Thursday, another cold front approaches and will introduce
chance of showers and storms. This front may have a little more
moisture to work with, but for now will keep only small chances
for rain across the region.

Regardless of any tstm chances in the forecast, it still does not
look promising for widespread rainfall, as many places will see
little to no rain through the period. In fact, the latest 13z
NBM probabilities for at least 0.50" of total rainfall from Sun-
Tue are still only 10-40% over the local area. This will only
exacerbate the recent dry conditions and set us up for what can
be 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 /05Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
As of 115 AM EDT Friday...

VFR is expected all of today and through most of the weekend.
Only cloud cover this morning is FEW-SCT high clouds over
central VA. A few CU may develop this aftn, but most areas stay
sunny. Light or calm S/SE winds this morning become 5-10 kt
this aftn. Winds could briefly become 10-15 kt at ORF as the sea
breeze becomes established. Light S flow continues tonight w/
generally SKC.

Outlook: Dry and VFR conditions are expected to prevail through
Sunday afternoon as high pressure remains centered off the
coast. There is a low chance for some isolated to widely
scattered storms Sun evening and again Mon afternoon into Mon
evening.
-- End Changed Discussion --

&&

.MARINE...
As of 305 PM EDT Thursday...

Key Messages:

- Sub-SCA marine conditions expected through the first half of the
weekend.

- Elevated southerly winds forecast to develop late Saturday through
Monday. Best chance for SCA will be Sun afternoon through Monday.

- Moderate rip current risk at all areas beaches continues
Friday. At least a moderate risk continues through the weekend.

High pressure remains offshore this afternoon. The afternoon sea
breeze is picking up a bit within the last couple of hours, but
still remaining below SCA thresholds. Latest wind obs show S/SE flow
around 10-15kt. Winds will diminish slightly overnight, becoming
more southerly by Fri morning. Very similar conditions Friday and
Saturday with S-SE winds continuing. S winds increase to ~15 kt in
the Chesapeake Bay and 15-20 kt in the coastal waters Saturday
evening/night. The strongest winds of the period are still expected
later Sunday and Sunday night as low pressure slides well N of the
area and a weak cold front approaches from the W. Peak winds are
expected late Sunday night in the 15-20 kt range in the
bay/rivers/sound and 20-25 kt range on the ocean. With frequent
gusts of 20-30 kt expected, small craft advisories look like a good
bet for most of the marine area (lower confidence in the upper
rivers and Currituck Sound). Winds remain elevated through early
Monday, before subsiding by the afternoon and evening. The direction
turns northwesterly behind the front Monday night-Tuesday. Regarding
tstm chances, a low chance is expected later Sunday, with a slightly
better chance Monday with the front.

Seas are 3-4 ft S and 2-3 ft N this afternoon and waves are 1-2ft
(up to 3ft at the mouth of the bay). Seas average around 3 ft for
Friday and Saturday. With the increased southerly flow Sat night-
early Mon, seas are forecast to eventually build to 4-6 ft N and 3-4
ft S. Waves also increase to 2-3 ft Sun/Sun night.

Rip currents: Rip current risk is moderate at all beaches for the
rest of today and into tomorrow. SE swell energy and ~3 ft nearshore
waves (could approach 3-4 ft at times across the NC OBX this aftn).
An elevated rip risk likely continues through the upcoming weekend
(highest threat shifting to nrn beaches Sat and Sun with the south
wind direction).

&&

.AKQ WATCHES/WARNINGS/ADVISORIES...
MD...None.
NC...None.
VA...None.
MARINE...None.

&&

$$

SYNOPSIS...JDM
NEAR TERM...RMM/MRD
SHORT TERM...MRD
LONG TERM...MRD
AVIATION...SW
MARINE...AM/SW