textproduct: Jackson

KEY MESSAGES

- Hot temperatures will continue the remainder of the week, but lower humidity should help to reduce heat stress, with dangerous levels of heat stress confined to along and northwest of the Natchez Trace.

- Dangerous levels of heat stress will build back in areawide this weekend through early next week.

DISCUSSION

Issued at 246 AM CDT Thu Sep 17 2026

Today through mid-next week (Wednesday)...

Through this weekend: The Gulf Coast states remain entrenched under a sprawling high at the surface and aloft (598 to 600DM). RAP analysis/water vapor imagery indicate the center of mid level high pressure remains over the Mid South to TN Valley region. This pattern will gradually shift westward today into Friday, leading anomalous warmth, some 8-15F above normal (95F to 101F). Drier air is evident in GOES East total PWs (0.9 to 1.3 inches) and is progged to shift into the region as the mid level high shifts westward. While it will remain hot, dangerous heat stress will be somewhat decreased. Lows will be seasonably warm, some 6-12F above (70-75F this morning and a touch cooler tonight to the south, 67-70F along and south of I-20, while warmer to the north, 71F-74F).

Highs continue to moderate into the weekend, with an influx of deeper moisture. A westward propagating upper low/surface trough over the northeast Gulf will lead to an influx of deeper moisture aloft and higher boundary layer moisture, which supports less mixing and more concerns of dangerous heat. Highs will moderate into the upper 90s to around 100F (97-102F), with 101-102F possible, especially in northern observation sites. Added some targeted Limited heat graphics in the HWO for today into the weekend (along and northwest of the Natchez Trace today into Friday and areawide into the weekend). Holding off on any heat headlines for now. Rain chances remain minimal, with some slight uptick in isolated/low chance rain and storm coverage in the Pine Belt late weekend on Sunday (15-30 percent).

Next week (Through next Wednesday): As the upper low weakens and another shortwave/cold core low propagates into the Mid West States through middle of next week, the mid level feature over the northeast Gulf is progged to lift northward. This feature will become absorbed in the mean flow to the north. This will lead to less focused moisture convergence but persistent deep moisture (PWs around 1.75 to greater than 2 inches). There is progged for another weak frontal/convergence zone and light northwesterly flow to sink into the area early next week. Combined with the ridge less stout and centered over east TX, highs will become less seasonably warm, dropping from 8F to 14F above to 6F to 12F above (95F to 100F early week to 91F to 95F by midweek). Rain and storm chances remain in the low chance range (15-30 percent) on average areawide, with medium chance (exceeding 30 percent) in the Pine Belt. Dangerous heat concerns will persist into early week and will continue to message HWO heat graphics for Monday and somewhat less oppressive heat through midweek. /DC/

AVIATION

(18Z TAFS) Issued at 1254 PM CDT Thu Sep 17 2026

VFR conditions wl prevail through the TAF period. /22/

PRELIMINARY POINT TEMPS/POPS

Jackson 95 70 97 71 / 0 0 0 0 Meridian 94 69 98 71 / 0 0 0 0 Vicksburg 96 70 97 71 / 0 0 0 0 Hattiesburg 93 67 96 69 / 0 0 0 0 Natchez 95 69 97 70 / 0 0 0 0 Greenville 99 73 100 73 / 0 0 0 0 Greenwood 99 72 100 72 / 0 0 0 0

JAN WATCHES/WARNINGS/ADVISORIES

MS...None. LA...None. AR...None.