694
FXUS64 KJAN 071859
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
159 PM CDT Mon Sep 7 2026

...New DISCUSSION...

.KEY MESSAGES...

- There is a marginal risk (level 1 of 5) for severe storms this
  afternoon into the evening along and south of I-20.

- Dangerous heat stress will persist across most of the area this
  afternoon and again across the western half of the area on
  Tuesday.


&&

.DISCUSSION...
Issued at 159 PM CDT Mon Sep 7 2026

A cumulus field has developed this afternoon in two areas -
across central LA and south MS and across east central MS. Much
like yesterday, low level lapse rates are quite steep given the
ample surface heating and low level moisture. This will provide
potential for another round of isolated to scattered storms this
afternoon, with lower chances in our northern/western areas where
even fair weather clouds are more sparse. DCAPE remains high
across the area, so wet microbursts resulting in damaging wind
gusts will be possible in some storms, with greater odds further
south where deep layer moisture is greater. Convection will
diminish in coverage after sunset.

Tuesday and Wednesday: The remnant surface front will continue to
stall and wash out over the next few days, with a Southeast US
surface ridge becoming a bigger player. The position of this high
favors the advection of a somewhat drier and...less hot...air
mass being wedged around the Appalachians. What would this mean
for us? Temperatures that are still above average but not as high
as what we have been seeing and increasingly marginal heat
indices, with sites less likely to reach heat advisory criteria
each day. As this modified airmass begins to move into the
eastern portion of the area tomorrow, we have clipped the heat
advisory to only cover our western half. And it`s possible by
Wednesday an advisory will not be needed at all. Diurnal
convection is still possible each day where deep layer moisture
will be greater, favored over southern/western areas tomorrow
then across the south on Wednesday.

Thursday through next Monday: Another weak cold front will
approach from the north at the end of the week but stall before
reaching our area. Increasing deep layer moisture will pool south
of this feature, resulting in higher rain chances over the back
half of the forecast period. Though it will still be hot, greater
prevalence of clouds and rain may continue to temper the heat
enough to avoid critical heat stress thresholds being met this
weekend into early next week. /DL/

&&

.AVIATION...
(18Z TAFS)
Issued at 1221 PM CDT Mon Sep 7 2026

Isolated to scattered convection is possible late this afternoon
through early evening mainly across central LA and south/east MS,
with potential for brief visby reductions and gusts to 50 kt. Very
brief patchy fog is possible around daybreak Tuesday morning.
Otherwise, VFR conditions are expected to prevail through the TAF
period. /DL/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       74  96  73  94 /  20  10   0  10
Meridian      73  93  72  94 /  20   0   0  20
Vicksburg     74  97  73  94 /  10   0   0  10
Hattiesburg   74  94  73  93 /  40  30  10  60
Natchez       74  97  73  95 /  20  40  10  20
Greenville    73 100  75  98 /   0  10   0   0
Greenwood     73  97  73  96 /   0  10   0   0

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 7 PM CDT this evening for MSZ018-019-025>028-
     034>036-040>043-047>066-072>074.

     Heat Advisory from 11 AM to 7 PM CDT Tuesday for MSZ018-019-
     025>028-034>036-040>043-047-048-053-054-059>061.

LA...Heat Advisory until 7 PM CDT this evening for LAZ007>009-015-016-
     023>026.

     Heat Advisory from 11 AM to 7 PM CDT Tuesday for LAZ007>009-015-
     016-023>026.

AR...Heat Advisory until 7 PM CDT this evening for ARZ074-075.

     Heat Advisory from 11 AM to 7 PM CDT Tuesday for ARZ074-075.

&&

$$

DL