447
FXUS64 KJAN 202030
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
330 PM CDT Thu Aug 20 2026

...New DISCUSSION...

.KEY MESSAGES...

- Dangerous heat stress conditions are expected across at least
  portions of the forecast area through Friday.

- Isolated to scattered severe storms capable of damaging wind
  gusts are possible across portions of the area today and Friday.

&&

.DISCUSSION...
Issued at 252 PM CDT Thu Aug 20 2026

Through Friday: A frontal boundary will sag slowly southward
toward the coast and help to focus scattered diurnally driven
storms for the remainder of the afternoon and into the early
evening, especially over northern portions of the area. Given how
hot and unstable the boundary layer conditions are, steep low
level lapse rates will support damaging microburst winds, and have
continued to message for a slight/marginal severe weather risk
this afternoon/evening. This threat will shift into southern
portions of the area Friday. Of course the dangerous heat threat
continues as well and have issued additional heat
warning/advisories accordingly. The heat will gradually become
more focused over southwest portions of the area, and have
adjusted our messaging to reflect this.

Weekend through early to mid next week: Global model guidance
indicate that a northwest flow pattern will evolve and persist
through the remainder of the forecast. A NW-SE oriented thermal
gradient will support the greatest heat stress over southwest
portions of the forecast area, but this doesn`t appear it will be
more than a limited to potentially elevated dangerous heat
situation. This pattern would support an occasional MCS threat,
but timing details are very uncertain, and overall rain chances
are not great in the mean. Unfortunately for those needing
rainfall, there are no strong signals for it at this point aside
from a gradual uptick in rain chances as we go later into next
week. /EC/

&&

.AVIATION...
(18Z TAFS) Issued at 1242 PM CDT Thu Aug 20 2026

VFR flight conditions will prevail through the period. Another
chance for scattered TSRA this afternoon through the evening with
gusty winds and reduced flight conditions at affected site. /SW/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       74  99  72  98 /  30  20  10   0
Meridian      73  97  72  98 /  20  30  10   0
Vicksburg     75  99  72  99 /  20  10  10  10
Hattiesburg   74  98  73  98 /  30  30  30   0
Natchez       75 101  73 100 /  10  20  20   0
Greenville    74  99  72  99 /  50  10   0  10
Greenwood     73  97  70  98 /  30  10   0   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 8 PM CDT this evening for MSZ018-019-025>066-
     072>074.

     Heat Advisory from 11 AM to 8 PM CDT Friday for MSZ018-019-
     025>039-044>046-050>052-056>058-065-066-073-074.

     Extreme Heat Warning from 11 AM to 8 PM CDT Friday for
     MSZ040>043-047>049-053>055-059>064-072.

LA...Heat Advisory until 8 PM CDT this evening for LAZ007>009-015-016-
     023>026.

     Extreme Heat Warning from 11 AM to 8 PM CDT Friday for
     LAZ007>009-015-016-023>026.

AR...Heat Advisory until 8 PM CDT this evening for ARZ074-075.

     Heat Advisory from 11 AM to 8 PM CDT Friday for ARZ074-075.

&&

$$

EC/SW