463
FXUS64 KJAN 172338 AAA
AFDJAN

Area Forecast Discussion...UPDATED
National Weather Service Jackson MS
638 PM CDT Thu Jul 17 2025

...New AVIATION...

.DISCUSSION...
Issued at 112 PM CDT Thu Jul 17 2025

Through This Weekend:

The primary feature of note in our region remains this easterly
tropical wave centered around Southeast Louisiana this afternoon.
Current loops of visible satellite imagery do a good job
illustrating the the area of tropical low pressure around the mouth
of the Pearl River. Ridging of high pressure over the interior of
the South is contributing to continued Elevated heat stress
conditions today. Air temps in the mid 90s and dew points in the
upper 70s to near 80 down the length of the Delta and Mississippi
River Valley have combined for heat index values of 105-112 so far
today. Upgraded a portion of the Heat Advisory generally down the
Mississippi River to an Excessive Heat Warning through this
afternoon due to the more persistent and intense heat there.
Elsewhere, increased deep moisture is limiting the heating
potential. Rain chances will expand coverage, so have not chosen to
extend a Heat Advisory into the daytime tomorrow with this forecast
issuance. A smaller Heat Advisory may be needed in the Delta, but
will allow another round of model guidance to capture the evolution
of this disturbance heading into the overnight/tomorrow time frame.

As the remains of this disturbance become absorbed in the general
flow over the CONUS, the chance for showers and thunderstorms will
shift northwestward and then out of our area. Cannot rule out
isolated heavy storms, but flow and positioning of the system as it
crosses our area will be less favorable for organized flash flooding
threat. If the system retains some concentrated core as it drifts
across, overnight convection near the center could produce heavy
rainfall over a small area. Will continue to monitor for this
potential, but think threat will remain south of our forecast area
at this current time. Rainfall amounts generally expected to be less
than 1 to 2 inches.

Into early next week:

In the wake of the tropical disturbance, upper-level ridging will
generally reestablish its presence over the region and retrograde to
the west. Ensemble mean 500mb height values place a 594dam ridge
squarely over the Interstate 40 corridor through the Ozarks and Mid-
South regions. This should promote hot weather and keep precip
chances a little more restricted in our forecast area. Current
guidance keeps POPs on the periphery of this ridge - mainly south
and east of the Natchez Trace corridor. More heat headlines may be
needed next week with the potential for more 105 to 110 or greater
heat index values. /NF/

&&

.AVIATION...
(00Z TAFS)
Issued at 629 PM CDT Thu Jul 17 2025

VFR conditions will prevail through 06Z with isolated SHRA/TSRA being
the only, temporary, exceptions in their vicinity moving
generally east to west. CIGS lower overnight to MVFR/IFR toward
dawn with increases in SHRA/TSRA attendant. CIGS improve to VFR
outside of SHRA/TSRA vicinity by 18Z. TSRA coverage/intensity
will maximize in the 19Z-00Z timeframe. Southern and central TAF
sites will see greater coverage of SHRA/TSRA overall through the
period. /86/


&&

.PRELIMINARY POINT TEMPS/POPS...
Jackson       75  90  74  91 /  20  80  20  50
Meridian      74  91  73  92 /  20  80  10  50
Vicksburg     76  90  75  90 /  20  80  30  50
Hattiesburg   76  91  75  94 /  20  80  10  70
Natchez       75  87  73  90 /  30  80  20  60
Greenville    76  92  75  90 /  10  50  10  40
Greenwood     76  93  75  90 /  10  60  10  50

&&

.JAN WATCHES/WARNINGS/ADVISORIES...
MS...Heat Advisory until 7 PM CDT this evening for MSZ028>033-037-043-
     048-053-059-060.

LA...Heat Advisory until 7 PM CDT this evening for LAZ007-015-023-024-
     026.

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

&&

$$

NF/NF/LP