Heat in Arkansas, August 29, 2024

Area Forecast Discussion
National Weather Service Memphis TN
545 AM CDT Thu Aug 29 2024

...New AVIATION...

.SYNOPSIS...
Issued at 300 AM CDT Thu Aug 29 2024

A Heat Advisory is in effect for much of north Mississippi this
afternoon for heat indices at or above 105 degrees. A couple more
days of heat and humidity are on tap before a series of cold fronts
come down Labor Day weekend and bring a cooler and wetter pattern
to the Mid-South. Daily scattered showers and thunderstorms are
in the forecast through late next week.

&&

.DISCUSSION...
(Today through Wednesday)
Issued at 300 AM CDT Thu Aug 29 2024

Today's heat is expected to have a more uncomfortable twinge of
humidity along with it due to the return of southerly flow and
resultant moisture advection. As such, dewpoints along our
southern few tiers of counties will surge into the mid to upper
70s this afternoon, especially across the MS Delta. A Heat
Advisory is in effect today from 11AM to 8PM CDT for much of north
Mississippi; heat indices should hover right around 105F or just
slightly above for these areas this afternoon. Tomorrow's forecast
is a little more of a question mark as convection makes more of an
appearance tomorrow and may tank heat indices. A small Heat
Advisory may be needed, but that call is too uncertain to make at
this time.

As alluded to, some much needed rain is returning to the forecast
starting this afternoon. A nondescript surface pattern suggests
today's PoPs (30-40%) will mostly be in the form of diurnally
driven scattered showers and thunderstorms. Depending on how much
rain we get this afternoon, patchy fog could become a nuisance on
the Friday morning commute as winds are once again expected to be
calm with low dewpoint depressions overnight.

A more synoptic scale frontal boundary looks to finally approach
the area tomorrow, marking the transitional period to a cooler and
wetter pattern. This is the first of two cold fronts forecast to
impact our area over the Labor Day weekend. As the first front
approaches tomorrow, more widespread showers and thunderstorms
will start to pick up from west to east. The 00Z HREF doesn't go
out quite that far yet, but the LREF ensemble mean paints a swath
of CAPE on the order of 1000 J/kg across the area on Friday and
Saturday afternoons. It's looking like the frontal passage timing
will not coincide with the max heating on either day, so we can
most likely expect poorly organized showers and thunderstorms
accompanying the front both Friday and Saturday.

WPC's forecast surface analysis depicts a second reinforcing cold
front following suit on Sunday. This will further knock
temperatures down into below normal territory and keep PoPs above
20% through Labor Day weekend. Long range guidance is still
hinting at the second front stalling out across the southeastern
portion of the CWA, which will create a humidity and temperature
gradient from northwest to southeast through midweek. The front
looks to finally clear by late next week.

CAD

&&

.AVIATION...
(12Z TAFS)
Issued at 544 AM CDT Thu Aug 29 2024

High pressure begins to lose its grip on the Midsouth. Possibly
some thunderstorms moving in from the south late today at TUP and
MEM and again before 18z at MEM tomorrow. Otherwise, VFR with S
winds 5-7kt during the day, 2-5kt at night.

30/Sirmon

&&

.MEG WATCHES/WARNINGS/ADVISORIES...
AR...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for ARZ049-058.

MO...None.
MS...Heat Advisory from 11 AM this morning to 8 PM CDT this evening
     for MSZ006-007-009>017-020>024.

TN...None.
&&

PUBLIC FORECAST...CAD
AVIATION...JDS