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247
FXUS62 KCAE 260018
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
818 PM EDT Tue Jun 25 2024

.SYNOPSIS...
Hot temperatures with heat indices over 100 F are expected to
continue through the period. Isolated to scattered showers and
thunderstorms should occur each afternoon and evening,
particularly in the eastern Midlands and coastal plain. As a
front approaches, better coverage is likely Thursday.
Increasing heat impacts Friday through the weekend. Another weak
front will move into near the area Monday with possible better
convective coverage.

&&

.NEAR TERM /UNTIL 8 AM WEDNESDAY MORNING/...
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KEY MESSAGES:
-Mostly clear with lows in the mid-70s.

Evening satellite imagery shows convective debris clouds
diminishing across the eastern Midlands with a few lingering
cumulus elsewhere. Mostly clear skies and dry conditions are
expected through the overnight hours with the potential for low
stratus and/or patchy fog towards daybreak. It will be a muggy
night as dewpoints rise into the 70s throughout the forecast
area. Temperatures meanwhile only fall into the mid-70s.
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.SHORT TERM /8 AM WEDNESDAY MORNING THROUGH THURSDAY NIGHT/...
KEY MESSAGES:
-Hot conditions to continue with max heat indices of 105-110
 likely on Wednesday.
-Isolated to scattered afternoon/early evening thunderstorms,
 greatest coverage in the southeast Midlands Wednesday.
-Highest chances of showers and thunderstorms Thursday, some
 possibly severe. Wind damage is the main threat.

Wednesday: Broad troughing to our north will steadily help
drive some weak height falls across the area as we move into
Wednesday. Moisture will pull northward as the lingering
boundary lifts along southerly low level flow. So much of the
area will yield dew points into the 70`s again as PWAT`s climb
to around 1.5". PWAT`s will be a bit limited by some weak
downsloping flow aloft and the relatively dry northwest flow
above 850mb but this allow for strong solar heating. So again
high temps will cruise into the upper 90`s or low 100`s and with
the enhanced moisture, heat indices will likely top out around
110; a heat advisory will likely be needed for parts of the
area. Shower and storm activity will remain generally confined
to the sea breeze and coastal plain, but will likely push
further west into the Midlands compared to Tuesday.

Thursday: Troughing will continue to dig across the eastern US
with an associated low pressure system and front dragging
southward towards our area. While the best height falls will
shift north of us across the Mid-Atlantic, low level moisture
and plenty of heating will allow for some modest destabilization
in the afternoon; even the over-mixed GEFS still yields a mean
near 1500 MU CAPE and near 1000 ML CAPE. So while the forecast
soundings are not extremely impressive for severe weather,
anytime we have a synoptic- mesoscale lift source, dew points in
the upper 60`s or 70`s, and high temps in the upper 90`s,
severe weather is possible.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
KEY MESSAGES:
-Increasing heat impacts expected Friday through the weekend
 with heat index values 105 to 110.
-Scattered afternoon thunderstorms each day.

Behind the boundary and trough passage on Thursday, broad flat
ridging will develop across much of the Southeast US. GEFS and
EC members are consistent in pulling the primary jet well north
across the Great Lakes, positioning us under the zonal,
slightly northwesterly flow regime of the ridge. Temps will
steadily climb each day through this period as the ridge builds
further and shifts east slightly. The warmest temps are expected
likely on Sunday with some downsloping component below 700mb in
the GEFS and EC means; NBM 75th percentile, which is verifying
well recently, is 100 F both Saturday and Sunday. Rain chances
increase sharply into Monday and Tuesday as the ridge breaks
down and more troughing digs to our north. Confidence is
relatively low on how this will materialize however given the
current pattern.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
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VFR conditions expected through the TAF period although there is
the possibility of some brief stratus around dawn Wednesday.

Upper ridge over the southwestern states continues to ridge into
the southeast. Afternoon convection has diminished and lingering
debris clouds should also dissipate through the evening. Winds
generally expected to be light and variable overnight although
some outflow winds from the southeast 5 to 8 knots expected the
first hour of the forecast. A 20 knot low level jet is forecast
overnight which should limit fog concerns but there is some
mixed signals for the potential of stratus development after
09z, particularly across the eastern Midlands and Pee Dee
region. HRRR shows the development of stratus with some higher
probabilities shown on the SREF at OGB but lower elsewhere,
while the MOS guidance and NBM guidance does not have any
stratus forecast. Compromised a bit and included a tempo group
for stratus at most favored location OGB from 09z-13z and kept
it out elsewhere but trends may need to be monitored in future
forecasts for potential inclusion as prevailing or at CAE/CUB as
well as moisture begins to return north overnight. Probabilities
are low at AGS/DNL for stratus. Winds pick up from the south
once the inversion breaks Wednesday and speeds should increase
to around 7 to 10 knots by afternoon.

EXTENDED AVIATION OUTLOOK...Increased chance of rain and
restrictions on Thursday and Friday as an upper trough moves
into the region.
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&&

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

$$