Damaging Winds in Mississippi, August 13 to 17, 2025

Area Forecast Discussion
National Weather Service Jackson MS
1240 PM CDT Wed Aug 13 2025

...New AVIATION...

.MESOSCALE UPDATE...
Issued at 1125 AM CDT Wed Aug 13 2025

Morning analyses reveal a very moist airmass over the area
(e.g.,12z JAN raob 2.16 PW). It looks like initial convective
precip development early this afternoon should focus over eastern
MS on the outer periphery of the disturbance centered to our
east, and also for locations along/west of the MS River where an
outflow boundary is approaching. Looking ahead, there are some
indications in the CAM guidance that outflow from these two areas
could meet and support additional convection well into the
evening for areas roughly along the I-55 corridor. Severe
microburst potential is on the low side once again, but locally
heavy rainfall could be a concern. Otherwise, the heat advisory
continues without change for today, and it will likely be issued
for a similar area for tomorrow. /EC/

&&

.DISCUSSION...
Issued at 244 AM CDT Wed Aug 13 2025

Today and Tonight: Early morning water vapor imagery/RAP analysis
showed our CWA in the weakness between two rather stout 593dam
highs. This will change little through tonight. The 00Z Wed JAN
sounding had a PWAT just over two inches. Wl maintain a moist
airmass through the period. Daytime heating of our moist airmass
will lead to scattered to numerous coverage of convection that will
be more numerous in the east thanks in part to a weak low noted over
southwest Alabama that will be moving to the east today. In our west
where the lower coverage of convection is expected, temperatures
will climb up into the mid 90s and combine with high humidity to
result in heat index values between 105F and 110F. A heat Advisory
will remain in effect for our western zones and a graphic
highlighting "Limit" heat stress will be posted for the central
portions of our CWA where peak heat index values will be around
105F. The convection will see a distinct diurnal trend and dissipate
during the evening. /22/

Thursday through Tuesday: The forecast remains on track and no
changes necessary. Heat continues to be the primary hazard. Our
area remains under the influence of a subtropical ridge, which
will gradually propagate westward along the southern CONUS. A
surge of tropical moisture on its western flank will maintain rain
chances through late week. As the subtropical ridge propagates
and builds westward over our area, heat indices will steadily
increase, while rain chances steadily decrease. Dewpoints remain
in the mid to upper 70s while temperatures climb to the mid to
upper 90s. Confidence continues to increase on the need for
expanded heat headlines to more portions of the area, with perhaps
a targeted extreme heat warning in the west, by this weekend.
Will maintain the HWO graphic depicting this this weekend.

The good news is this heat looks to be short lived thanks to a
tropical system in the western Atlantic and a digging upper trough
over the northeast. This tropical system (Erin) becomes somewhat
phased with the upper trough over the northeast, helping to lock in
drier northerlies over the region. The push of drier air should
allow for deeper mixing in the afternoons, thus dewpoints dropping
to the low 70s with pockets of upper 60s. While there is still
uncertainty at this time considering moist fuels and anticipated
antecedent rainfall, this could open a window for a low end fire
risk next week, particularly with the combination of drier air and
hotter temperatures./SAS/

&&

.AVIATION...
(18Z TAFS)
Issued at 1235 PM CDT Wed Aug 13 2025

VFR conditions will prevail through the period however scattered
to numerous TSRA will develop this afternoon with the greatest
coverage in the east possibly deteriorating flight categories. The
TSRA will gradually dissipate after 00Z Thu and VFR conditions
are expected to prevail through the end of the TAF period. Fog/low
stratus will be possible across southeastern TAF sites
PIB/HBG/MEI after 10Z before dissipating by 15/16Z. /KP/

&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       74  94  74  94 /  30  70  20  60
Meridian      73  93  73  94 /  30  70  20  60
Vicksburg     74  94  75  94 /  40  70  20  60
Hattiesburg   75  95  75  95 /  30  60  20  50
Natchez       74  92  74  94 /  30  70  20  50
Greenville    74  94  74  93 /  30  60  20  40
Greenwood     74  95  74  94 /  40  60  30  50

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 7 PM CDT this evening for MSZ018-019-025-034-
     035-040-041-047-053-059-060.

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

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

&&

EC/SAS20/KP