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221
FXUS62 KCAE 291508
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
1108 AM EDT Wed May 29 2024

.SYNOPSIS...
Drier and cooler weather will continue moving into the region as
high pressure builds in from the upper Mississippi Valley.
Moisture is expected to return to the region by the weekend. This
will result in mainly diurnally driven isolated to scattered
afternoon and evening showers and thunderstorms early next week.
Temperatures are expected to be at or slightly below normal
into the weekend then a warming early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
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A closed upper level low is positioned over the Great Lakes
region/Ohio Valley, with its associated broad upper level trough
extending across most of the eastern U.S. Meanwhile, an upper
level ridge is in place over the Rockies. At the surface, weak
high pressure continues to build into the region.

A very dry northwest flow aloft is in place across the area,
driving precipitable water values down to 0.7"-0.9" inches. With
the drier air aloft also comes lower humidity and dewpoints,
which should bottom out into the upper 40s and lower 50s this
afternoon, resulting in minimum relative humidity values of
25-30%. Sunny skies are in place across the area, but model
soundings do show a slight increase in mid level moisture later
this afternoon, so a few clouds are expected to spread into the
area.

Temperatures are rapidly rising late this morning and have made
a few upward adjustments to forecast highs today to account for
current trends. Most areas should experience highs in the upper
80s to near 90, which is above normal but still slightly cooler
than yesterday.

A reinforcing cold front will push south through the forecast
area tonight bringing some cooler air to the region. Skies
should be mostly clear with good radiational cooling expected
and expect lows to drop into the upper 50s to lower 60s.
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&&

.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Dry northwest flow aloft as an upper level trough in the
Northeastern states dives southeast to off the Mid Atlantic and
Carolina coast Friday. Strong surface ridge centered over the
Great Lakes and Ohio Valley will be building to the south and
east, especially by Friday. The air mass will become quite dry
by Friday with precipitable water at or below 0.5 inches. A few
fair weather clouds across the north CWA Thursday as short wave
trough/upper level jet moves southeast across NC/northern SC.
Mainly Sunny skies Friday with strong subsidence and dry air.
Cold advection Friday so probably the coolest day of the week.
Highs both days in the low to mid 80s. Overnight lows falling
into the mid 50s by Friday night as more favorable radiational
cooling conditions expected with the surface ridge building into
the area.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
The ensembles suggest mid level ridging over the area early in
the weekend so expect temperatures to recover and moisture for
convection will be limited. The surface ridge will shift off the
coast by Sunday. A short wave trough moving east of mid
Mississippi Valley is expected to break down the ridge and
moisture increases early next week. The question is the degree
of moisture flux into the area. The ECMWF ensemble and GEPS
suggest a weaker short wave/less amplified than the GFS. This
results in a weaker moisture transport and stronger ridging over
the area into early next week. So, cut pops a bit Sunday
through Tuesday From the NBM although isolated to scattered
diurnally driven showers and thunderstorms can be expected
Sunday through Tuesday. Overall instability appears weak through
the period with even the GEFS, which is most aggressive with
pops, having relatively low probability of CAPE > 500 J/kg
through the period. Temperatures should warm to near normal with
surface ridge offshore and air mass modification.

&&

.AVIATION /15Z WEDNESDAY THROUGH SUNDAY/...
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VFR conditions expected through the 24 hr TAF period.

A dry air mass continues to build into the region today with a
secondary cool front pushing south through the Midlands tonight.
West-northwest around 5 to 10 knots are expected today with
some gusts to 15-18 knots possible during the afternoon. Skies
should be mostly clear through the period with some scattered
high clouds and mid afternoon diurnal cumulus clouds.

EXTENDED AVIATION OUTLOOK...Restrictions not expected through
the end of the week. Low chance of restrictions this weekend.
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&&

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

&&

$$