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820
FXUS62 KCAE 181025
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
625 AM EDT Wed Sep 18 2024

.SYNOPSIS...
An upper low will remain over the area today sparking scattered
showers and promoting mostly cloudy skies. High pressure will
build into the area from New England over the weekend into early
next week with dry and seasonable temperatures expected.

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.NEAR TERM /THROUGH TONIGHT/...
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Key Message(s):

- Expect scattered showers today and a few thunderstorms

The upper level low over the NC/SC Piedmont will hang over the
region today. The cold pool aloft and associated shortwave
energy has sparked light showers this morning moving from the
CSRA eastward across the Midlands. Rain amounts should be
limited to just a few hundredths. Convection will increase in
coverage and intensity this afternoon as the upper low and vort
max shifts east and convection is enhanced by daytime heating.
We would expect to see some thunderstorms in the afternoon with
mean SREF muCAPE values around 500 to 750 J/kg with highest
values along the coastal plain. The threat of severe weather is
low given the weak instability. Cloud cover, showers, and below
normal 500 mb heights support below normal daytime temps with
highs in the low to mid 80s. Showers should diminish during the
evening as the upper low shifts to our east and we lose daytime
heating. Lows overnight in the mid to upper 60s.
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.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Key Message(s):

- Isolated to scattered showers Thursday, drier Friday.
- Seasonable temperatures.

Upper low that`s been traversing across the region the past few
days will finally be moving off to the east through the day
Thursday. Associated trough axis will then move off the east
coast Friday. Enough moisture and weak instability on the
backside of the exiting low could produce isolated to scattered
showers/storms by Thursday afternoon, primarily across the
northeastern counties. As the low and trough axis move offshore,
northwesterly winds aloft will help usher in drier air. Skies
become partly cloudy, allowing a good amount of sunshine through
the day. This will bring afternoon highs into the low to mid
80s both days. Overnight lows fall into the low to mid 60s.

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.LONG TERM /SATURDAY THROUGH TUESDAY/...
Key Message(s):

-Trending drier for the weekend into early next week with
 seasonable temperatures

Really not too much change in the longer range forecast. Upper
trough will be off the east coast, while some ridging builds
into the area from the west through the weekend. This combines
with surface ridge building southward from New England to keep
dry weather in the majority of the longer term period. Next
chance for any rainfall appears to be just outside of the
current forecast period. Temperatures remain seasonable
with highs in the upper 70s to mid 80s, and lows mainly in the
60s.

&&

.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
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MVFR cigs possible near daybreak early this morning and again
Thursday morning. We expect scattered showers and possibly
thunderstorms today which may limit visibility.

An upper level system will linger over the region today
promoting scattered convection and low clouds. There may be a
period of MVFR ceilings at all TAF sites before 15Z, clearing
thereafter. There will be a few light showers across the region
through the morning. The showers may reduce visibilities briefly
but rain amounts should be light and confidence in vis lower
than 6 SM is low. Convection should increase in coverage and
intensity during the afternoon as thunderstorms also develop.
It`s uncertain whether coverage will be high enough to justify
mention of thunder or restrictions at the TAF sites at this
time so will continue to carry VCSH. Winds will pick up around
15Z, generally out of the south at 7 knots or less but become
light and variable by late afternoon.

Late Wednesday night into early Thursday morning, models
indicate the potential for another round of low clouds and
MVFR/IFR ceilings at all TAF sites. The light winds and
decreasing cloud cover could also lead to the typical fog
problems at AGS.

EXTENDED AVIATION OUTLOOK...Drier air late this week should
limit the threat of restrictions. As moisture begins to increase
late this weekend and early next week we could see additional
restrictions develop.
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.CAE WATCHES/WARNINGS/ADVISORIES...
SC...None.
GA...None.

&&

$$