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021
FXUS62 KCAE 250717
AFDCAE

Area Forecast Discussion
National Weather Service Columbia SC
317 AM EDT Tue Jun 25 2024

.SYNOPSIS...
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Hot temperatures are expected to continue through the period.
Isolated to scattered showers and thunderstorms should occur
each afternoon and evening, with better coverage likely
Thursday as a weak front sets up near the area. Increasing heat
impacts Friday through the weekend. Another weak front will
move into near the area Monday with possible better convective
coverage.
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&&

.NEAR TERM /THROUGH TONIGHT/...
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KEY MESSAGES:
-Heat continues to hold on over the area with max heat indices
 over 100.

A front remains oriented from southwest to northeast in the eastern
portion of the forecast area denoted by the significant low level
moisture gradient with dew points in the 70s in the SE and in the
50s to the NW. High pressure ridging into the area with water vapor
satellite imagery indicating fairly substantial mid-layer dry air
continues to push in from the NW. Above average temperatures
continue today with 850mb temperatures slightly higher,
although not expecting downsloping like yesterday. As a result,
high temperatures will likely be similar to yesterday, mainly in
the upper 90s to around 100. Drier air expected to mix down to
the surface, keeping dew points a bit lower, generally in the
mid to upper 60s, which will likely keep heat indices below heat
advisory criteria but still in the triple digits for most of
the area. Most of the area expected to remain dry, although
isolated storms may develop near the boundary, which is not
expected to move much of the course of today. Mild overnight
lows continue, in the low to mid 70s.
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&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
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KEY MESSAGES:
-Hot conditions to continue with max heat indices of 100-105.
-Widely scattered 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 and Wednesday night...The frontal boundary appears to
lift to the north and will probably become stationary near the
central or northern Midlands. There will be drier air in the
west with the GFS and ECMWF showing lower precipitable water
from north GA into western SC. Moisture maximized in the coastal
Plain and southeast Midlands. Expect 1.5 inches to 1.7 inches
near and southeast of the frontal boundary. Upper heights remain
elevated but the ridge center shifts west as an upper trough
moves east of the Mississippi River. Main short wave trough
appears to be well west of the region, across the Tennessee
Valley into the Gulf coast, so trigger lacking other than the
weak convergence near the front and sea breeze. Moderate
instability possible although some mid level capping in the west
and limited moisture especially above 3km. Low to mid level
lapse rates are quite steep with temperatures rising to near 100
degrees. Temperatures guidance is quite consistent with
continued heat wave despite approaching upper trough. Soundings
suggest strong inverted V especially to the west near the drier
air. Overall shear remains relative weak. Convective coverage
expected to be widely scattered to scattered mainly focused near
the sea breeze front and higher theta-e air across the east.

Thursday and Thursday night...Positively tilted upper trough
moving into the region Thursday with increasing moisture. Deeper
shear remains to the north across the Mid Atlantic. But short
wave triggers expected in the afternoon. Another surface
boundary will move into the area to provide convergence.
Instability appears weak to moderate but somewhat uncertain.
Capping should be weaker. Steep low to mid level lapse rates
and inverted V sounding, possible stronger lift support higher
threat for pulse severe storms. Temperatures might be slightly
cooler but still hot.
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&&

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

Ensembles are in good agreement showing a strengthening upper ridge
aloft Friday through the weekend. Diurnally driven scattered showers
and thunderstorms are possible each day. With subsidence through
Saturday, continued to go below the NBM pops. Temperatures will
rise through the weekend beneath the building ridge, and
confidence high for significant heat impacts. Another front will
move into the area by late in the weekend/early next week and
perhaps higher chance of showers.
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&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
VFR conditions expected through the TAF period.

Drier air continues to move in over the terminals early this
morning with scattered clouds around 10kft. Winds remain around
5 kts out of the NE overnight at the terminals with winds
shifting more easterly after sunrise between 5 to 10 kts.
Cumulus field develops around 5kft late morning with highest
chance for any showers or thunderstorms east of the terminals.
Winds generally becoming light and variable after sunset
tonight.

EXTENDED AVIATION OUTLOOK...Increasing chances for afternoon
scattered showers and thunderstorms and associated restrictions
through Saturday.

&&

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

&&

$$