Excessive Heat and Heat in Missouri, August 15 to 16, 2024

Area Forecast Discussion
National Weather Service Memphis TN
658 AM CDT Thu Aug 15 2024

...New AVIATION...

.SYNOPSIS...
Issued at 346 AM CDT Thu Aug 15 2024

Dangerous heat will begin today as heat index values climb above
110 degrees for a large portion of the Mid-South. In addition, an
unsettled weather pattern will develop tonight with daily chances
of severe storms through Saturday. By Sunday, a cold front will
bring much more tolerable conditions back to the region.

&&

.DISCUSSION...
(Today through Wednesday)
Issued at 346 AM CDT Thu Aug 15 2024

Heat and humidity will plague the Mid-South today as a 594 dam
ridge centers over the ArkLaTex region. Efficient moisture return
will place dewpoints into the upper 70s, with a few areas possibly
hitting the 80 degree mark by this afternoon. Bottom line: this is
dangerous heat with heat index values forecast as high as 114 F.
The Excessive Heat Warning has been expanded to include the
western half of the forecast area, with the remainder of the Mid-
South encompassed by a Heat Advisory. If you must be outdoors
today, we urge that you exercise caution and take frequent breaks
to hydrate and cool off.

Rain chances return late tonight for areas near the Kentucky
border with storms firing along a remnant outflow boundary.
Timing of storms will greatly impact severe weather chances as
SBCAPE and bulk shear values remain lack luster overnight. A few
storms may become strong with gusty winds the primary concern.
Expect Friday morning's convection to fizzle out by midday,
leaving the Mid-South susceptible to another hot and muggy day.
Additional heat headlines may be needed Friday as afternoon highs
soar to the mid and upper 90s.

Also on Friday, a large upper level trough will traverse the
Midwest, ejecting a slow moving cold front towards the Mid-South.
Additional storm development is likely Friday afternoon and
evening. However, exact timing of convective initiation remains
unclear due to uncertainty regarding how Friday morning's
convection influences atmospheric recovery. If a storm can get
going before sunset, a damaging wind and large hail threat may
emerge. In addition, severe weather chances remain on Saturday as
the aforementioned front inches into the region. Overall, the
threat looks relatively mild due to bulk shear remaining below 30
kts. The greatest chance for storm development exists in north
Mississippi, where a damaging wind threat may develop in the
afternoon / evening hours. As such, the Storm Prediction Center
has included the Mid-South in a Marginal Risk for severe storms on
both Friday and Saturday.

By Sunday, the front will push out of the region and bring
slightly cooler temperatures back to the forecast. The beginning
of next week will be much more tolerable with afternoon highs in
the mid to upper 80s.

ANS

&&

.AVIATION...
(12Z TAFS)
Issued at 644 AM CDT Thu Aug 15 2024

VFR conditions will persist through the period. Mainly dry
conditions this afternoon and evening. A decaying complex of
storms will approach the northern sites after midnight. Confidence
of TSRAs or SHRAs on site remains low, but high enough to carry a
VCTS.

AC3

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for ARZ009-018-026>028-035-036-048-049-058.

MO...Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for MOZ113-115.

MS...Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for MSZ001-007-008-010>012-020-021.

     Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for MSZ002>006-009-013>017-022>024.

TN...Excessive Heat Warning from 11 AM this morning to 9 PM CDT this
     evening for TNZ001-002-019-048-049-088.

     Heat Advisory from 11 AM this morning to 9 PM CDT this evening
     for TNZ003-004-020>022-050>055-089>092.

&&

PUBLIC FORECAST...ANS
AVIATION...AC3