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271
FXUS62 KCAE 191847
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
247 PM EDT Wed Jun 19 2024

.SYNOPSIS...
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High pressure along with dry weather and near normal
temperatures are expected through Thursday. Unsettled
conditions are possible by late in the week into the weekend as
moisture moves in from the Atlantic. Well above normal
temperatures are expected by Sunday into early next week.
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.NEAR TERM /THROUGH TONIGHT/...
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Cumulus have once again developed over the area as easterly flow
persists due to high pressure off the coast of New England.
Aloft the upper level ridge remains centered over much of the
eastern US with drier air aloft. With the high and upper level
ridge controlling the region the 12z CHS sounding along with
with forecast soundings continue showing a strong subsidence
inversion over the area. This is apparent in the cumulus which
have developed as vertical extent is minimal with the exception
in the southeastern Midlands where a bit better developed
cumulus are moving in from the coast. Through this evening
expect little change with some additional cumulus developing
however any potential showers will be confined to the far
southeastern Midlands and very southern CSRA as the slightly
better developed cumulus move into the area. With sunset and
loss of heating the cumulus will dissipate with mostly clear
skies overnight. Wind gusts will also diminish with sunset with
winds remaining 5 to 10 mph overnight. Afternoon high
temperatures remain on track for the low 90s with lows tonight
in the mid 60s.
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.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
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High pressure remains in place at the surface and aloft Thursday as
the pattern will be similar to Wednesday. Weaker onshore flow will
lead to less moisture, especially in the low levels so while
scattered cumulus may develop, showers are not expected as PWATs
will struggle to exceed an inch. High temperatures expected to be
near today`s highs. A weaker low level jet Thursday night along with
drier conditions should lead to overnight lows being a degree or two
cooler, in the mid 60s.

Gradual warming expected into Friday as the upper ridge retrogrades
and will be centered over the TN Valley. Temperatures at 850mb rise
to near or slightly above normal, leading to highs in the low to mid-
90s across the forecast area. A surface trough located offshore will
begin to move towards the area around the flow of the upper ridge.
This will lead to increasing moisture flowing into the forecast
area, although models remain consistent in keeping the deepest
moisture to the south. PWATs increase sufficiently to support at
least a chance of afternoon showers and thunderstorms south of I-20.
This increased moisture will also lead to warmer overnight lows, in
the upper 60s to around 70.
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.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
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Warming is expected to continue into this weekend as upper ridging
continues to hang on over the Southeast. NAEFS indicates that by
Sunday and Monday, 850mb temperatures will exceed the 90th
percentile. Little change in the overall high temperature forecast
in blended guidance or the spread through at least Monday with high
confidence (greater than 70%) in high temperatures exceeding 95F
each day. With sufficient low level moisture (dew points around
70F), confidence continues to increase in max heat indices reaching
or exceeding 100F Saturday through Monday. Also worth noting that
blended guidance continues to favor warm overnight lows, remaining
in the low to mid 70s. There remains uncertainty beyond Monday as
guidance continues to show the ridge beginning to break down as an
upper trough approaches the region and blended guidance begins to
show greater spread in temperatures. That being said, no major
cool down is expected anytime soon. GEFS probabilities indicate
increasing probability of PWATs increasing to above 2 inches by
Sunday into early next week which will lead to increasing chances
for diurnally driven thunderstorms. With the potential for greater
dynamics with an approaching upper trough, highest chances for
showers and thunderstorms will be Monday and Tuesday.

More information on the potential for moderate to major heat risk
late in the forecast period can be found at
wpc.ncep.noaa.gov/heatrisk.
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.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
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VFR through the TAF period.

High pressure remains in control of the region with easterly
winds and scattered cumulus across the terminals. Through this
evening expect the cumulus to continue developing then dissipate
with sunset with mostly clear skies overnight. Winds will remain
easterly through the period with gusts around 18 knots into this
evening then diminishing to 5 to 8 knots overnight. As the
morning inversion breaks winds will return to around 10 knots
with gusts up to 18 knots from 15z through the end of the
period.

EXTENDED AVIATION OUTLOOK...Brief restrictions possible in
isolated to scattered afternoon and evening thunderstorms Friday
through Sunday.
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&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.

&&

$$