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303
FXUS62 KCAE 240728
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
328 AM EDT Fri May 24 2024

.SYNOPSIS...
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A frontal boundary will approach the region Friday and is
expected to stall near the area resulting in chances of showers
and thunderstorms through the weekend. Another more organized
system is expected to be crossing the eastern US Monday and
Tuesday with additional chances for thunderstorms. Drier weather
is expected to return Wednesday.
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.NEAR TERM /THROUGH TONIGHT/...
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Early this morning: A shortwave moving along the NC/SC border
is generating some thunderstorms across the far northern portion
of the forecast area. This will likely continue over the next
several hours. Elsewhere, scattered higher cumulus and cirrus
clouds passing over the forecast area will keep low temperatures
this morning on the mild side.

A moist airmass remains in place today with satellite derived
estimates around 1.6 inches and dew points in the upper 60s
currently. HREF indicating a high probability (70 to 80
percent) of PWATs remaining above 1.5 inches throughout the
course of today, with probs a bit higher in the CSRA.
Temperatures once again expected to be a few degrees above
average, around 90F, which should lead to destabilization into
this afternoon. Forcing may be a bit limited as recent model
runs have trended a bit less defined with a shortwave moving
into the area, or at the very least, timing is difficult to pin
down. The entire area remains in a marginal risk for severe
weather today with moderately high probability of sbCAPE
exceeding 1000 J/kg, although there is still decent amount of
spread in model guidance as to the degree of destabilization
with some models indicating strong destabilization across the
area. Deep layer shear will also be somewhat limited, although
HREF guidance does indicate it may be slightly higher in the
CSRA which may support at least some multi-cell clusters. Dry
air aloft does support the potential for isolated damaging wind
gusts in any stronger storms that do form with a secondary but
lower hail threat. Still a fair bit of uncertainty in the timing
and coverage but in general, expect scattered thunderstorms to
develop late this afternoon into evening depending on the exact
timing of the shortwave. Lows tonight once again remain mild, in
the mid to upper 60s.
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.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
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Saturday and Saturday Night: Short wave energy shifting through
early on Saturday will allow for an upper trough to deepen over the
Carolina coast, followed by ridging gradually building from the west
later in the day into Saturday night. On the backside of this
system, a northwest flow aloft will develop across the area,
advecting somewhat drier air into the area and allowing precipitable
water values to fall into the afternoon. This drier air should limit
the overall coverage of any convection, with isolated to scattered
showers and thunderstorms expected. HREF soundings indicate moderate
to strong instability in place with CAPE values between 1500-2000
J/kg. In addition, a pronounced inverted-V sounding and DCAPE values
approaching 1000-1200 J/kg would support a damaging wind threat for
any storms that do manage to become severe. Overall, the severe
threat looks favorable, but with limited storm coverage.

Sunday and Sunday Night: Upper level ridging will strengthen over the
region with a southerly low-level flow becoming established. A
slight increase in moisture advection is expected with precipitable
water values rising above 1.5 inches, but strong subsidence aloft
and no significant forcing mechanism should limit the coverage of
any convection to isolated or scattered at best. The best coverage
appears to be across the northern portion of SC in closer proximity
to short wave energy shifting across the northern periphery of the
ridge. Instability remains moderate to strong across the area. With
ample dry air in the mid-levels of the atmosphere there is the
potential for a few storms to become strong to severe, with damaging
wind once again the primary threat. It should also be noted that
Sunday could be one of the warmest days of the period, with heat
indices approaching the triple digits in many locations.
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&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
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Heights will fall on Monday in response to an upper trough digging
over the Great Lakes region/Ohio Valley, pushing an associated cold
front towards the area. Strong diurnal/compressional heating ahead
of any front will result in high levels of instability across the
area. Isolated to scattered showers and thunderstorms will be
expected once again, but with higher levels of instability and
stronger forcing ahead of the front, expect a greater overall
potential for severe weather across the area.

The GFS and ECMWF ensembles show the upper trough axis passing over
the area on Tuesday, potentially resulting in the greatest coverage
of showers and thunderstorms this week. However, instability appears
more limited than previous days, reducing the overall threat for any
severe weather. Once the upper trough passes to the east,
significantly drier air will overspread the area, greatly reducing
the potential for any diurnal convection toward the end of the
forecast period.
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&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
VFR conditions generally expected during this forecast period.

Shower and storm activity ended up being few and far between
yesterday and as a result, low level moisture will be lacking to
support any stratus developing across northern portions of the
forecast area. Blended guidance has trended towards VFR
conditions at all terminals through the early morning hours. Do
expect scattered showers and thunderstorms to develop across the
area this afternoon into this evening but confidence is not high
enough to include TS in the TAF at this point. Winds increase
out of the west late morning into afternoon between 5 to 10
knots.

EXTENDED AVIATION OUTLOOK...Restrictions possible at times
through early next week in afternoon and evening showers and
thunderstorms.

&&

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

&&

$$