475
FXUS64 KJAN 051026
AFDJAN

Area Forecast Discussion
National Weather Service Jackson MS
526 AM CDT Sat Jul 5 2025

...New AVIATION...

.DISCUSSION...
Issued at 109 AM CDT Sat Jul 5 2025

Through late next week (Friday)...

Increasing heat stress remains the focus into this holiday weekend
through next week. Be sure to stay cool and hydrated, and use
sunscreen if enjoying time outdoors.

1018-1020mb sfc high situated over the OH Valley will gradually
propagate to the east over the next several days, with 592DM 500mb
ridge building eastward. Upper level flow is beginning to cut-off
low over Carolinas, while Tropical Depression Three is situated off
the Atlantic seaboard, with any concerns of impacts focused in
the Carolinas. Mid to upper level flow will gradually shift
easterly to more southerly into early next week. Moisture remains
confined in two areas, southwestern third of the area, generally
southwest of a line from Vicksburg to Natchez and another area in
the Golden Triangle southeast along the Hwy 45 corridor along the
MS/AL state line. Morning GOES East water vapor total
precipitable water (PWs) indicate 1.4 to 1.6 inches, while closer
to 1.1 inches in the heart of the region in northern, central and
southern MS. This will keep the best isentropic ascent/convergence
in the Pine Belt today, where isolated rain and storm chances
will reside. There will be some subtle northeasterly flow, so an
isolated stronger storm can`t be ruled out.

As the ridge builds eastward into the Mid MS Valley, the cutoff low
will retrograde westward in the northern Gulf. Expect moisture to
continue to build in, closer to 2 inches into early to middle
portion of next week. Seasonably warm highs, some 3-6F above (92-
97F), are expected through the weekend and into the following week.
This combined with return flow, boundary level dewpoints will peak
in the 72-77F range during the work week. With some drier air around
this weekend, some lower relative humidity (RH) in the 850-500mb
layer may enhance aftn mixing (sfc dewpoints falling as low as the
upper 60s the 66-71F range through Sunday), helping keep peak
aftn heat indices below heat headline potential (101-104F today).
Confidence remains for a "Limited" heat graphic through the
weekend but going to expand it areawide. In addition, heat stress
will worsen into next week, so will introduce an "Elevated" along
and west of the Interstate 55 corridor, generally along and west
of a line from Grenada to Jackson to Columbia MS. Potential
threat area adjustments and heat headlines will likely be needed
as we get closer to early to middle next week. Increased
convergence and rain and storm coverage will in the 15-45% range
both Sunday and Monday, shifting out of the Pine Belt to areawide
into next week, and 35-65% by Wednesday to Friday. This could keep
highs in check near seasonable levels, but there has been some
lowered trend in recent blended guidance. However, dewpoints will
still remain high in the mid to upper 70s. The hottest timeframe
could be mid morning to midday before convective initiation.
Lastly, with daily diurnal convection and trough/shear axis
dropping southward, combined with favorable lapse rates and
westerly flow/shear, some strong to isolated severe storms can`t
be ruled out into late next week. Both will have to be assessed on
day-to- day basis. /DC/

&&

.AVIATION...
(12Z TAFS)
Issued at 525 AM CDT Sat Jul 5 2025

VFR conditions and a light wind will prevail through the TAF
period. Areas of patchy fog may briefly lower visibilities through
16Z./KP/

&&

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

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...None.
LA...None.
AR...None.
&&

$$

DC/DC/KP