textproduct: Jackson

KEY MESSAGES

- Dangerous heat stress this week, with afternoon heat index values generally between 105F-110F.

- Marginal Risk for isolated severe storms across portions of east central & southeast Mississippi late this afternoon & evening.

DISCUSSION

Issued at 229 AM CDT Tue Jun 30 2026

Today through next Monday...Dangerous heat stress currently remains the primary hazard through much of this forecast period. However beginning today, increasing rain chances across the CWA could affect just how high afternoon heat index values climb. These better rain chances will exist across the forecast area into the Independence Day weekend as high pressure aloft has become positioned east northeast of the region. As a series of disturbances caught up in easterly flow aloft track from east to west across the Deep South on the southern periphery of this aforementioned high, mainly afternoon and evening showers and storms will develop in this hot, humid, and unstable environment.

For today, while much of the CWA will again remain rain free, a chance for a mainly late afternoon and evening shower or storm will exist across mainly East Central and Southeast Mississippi. While not overly impressive, the combination of this unstable airmass and some slightly increased mid-level shear could result in an isolated severe storm across the southeast portion of the CWA late today. While confidence in this is currently low, a stray storm capable of producing a damaging wind gust can't be ruled out. That being said, given this overall pattern setup across the Southeast United States, and the again unstable airmass across the region, daily analysis of local RAOBs, high-res model data, and satellite and radar data will need to be made and paid close attention to to discern the risk for microbursts and any possible east to west moving MCS that could affect the forecast area during this forecast period.

As far as the heat stress is concerned, highs will climb into the mid and upper 90s today and Wednesday, with mainly mid 90s forecast areawide Thursday into early next week. These temperatures, coupled with dew points in the 70s, will continue to yield afternoon heat index values above the century mark during this time. At the moment, heat indices continue to look their highest today and again on Wednesday, as values peak up around 110F. As a result, a "Heat Advisory" is in effect for today, and will be extended into Wednesday. Confidence in indices between 106F-110F remains high enough that we'll continue to advertise an "Elevated Threat" for dangerous heat stress conditions in the HWO. We will also continue to evaluate on a daily basis whether the extension of the "Heat Advisory" is needed later into the week, and potentially into the upcoming Independence Day weekend. /19/

AVIATION

(18Z TAFS) Issued at 1229 PM CDT Tue Jun 30 2026

VFR conditions and light to calm winds are expected to prevail at the TAF sites through the period. There is a slight chance for showers or a thunderstorm near KHBG or KPIB near 00Z Wednesday, but the chance for impacts from thunder is too low to mention in the TAF at this time. /NF/

PRELIMINARY POINT TEMPS/POPS

Jackson 96 77 95 75 / 0 10 40 20 Meridian 98 77 96 75 / 10 10 20 10 Vicksburg 95 77 95 76 / 0 0 40 10 Hattiesburg 97 76 95 75 / 10 20 50 20 Natchez 97 77 95 75 / 0 0 60 10 Greenville 96 77 96 77 / 0 0 20 10 Greenwood 99 77 99 76 / 0 0 30 10

JAN WATCHES/WARNINGS/ADVISORIES

MS...Heat Advisory until 9 PM CDT Wednesday for MSZ026>033-037>039- 044>046-050>052-056>058-060>066-072>074.

Heat Advisory until 10 AM CDT Wednesday for MSZ018-019-025- 034>036-040>043-047>049-053>055-059.

Extreme Heat Warning from 10 AM to 9 PM CDT Wednesday for MSZ018- 019-025-034>036-040>043-047>049-053>055-059.

LA...Heat Advisory until 9 PM CDT Wednesday for LAZ007-008-015-023- 024-026.

Heat Advisory until 10 AM CDT Wednesday for LAZ009-016-025.

Extreme Heat Warning from 10 AM to 9 PM CDT Wednesday for LAZ009- 016-025.

AR...Heat Advisory until 9 PM CDT Wednesday for ARZ074.

Heat Advisory until 10 AM CDT Wednesday for ARZ075.

Extreme Heat Warning from 10 AM to 9 PM CDT Wednesday for ARZ075.