textproduct: Jackson

KEY MESSAGES

- We will be monitoring a stormy weather pattern for additional flash flood and severe weather threats this week. - Dangerous heat stress will return for much of the area Monday and continue through the upcoming week.

DISCUSSION

Issued at 355 AM CDT Sun Jun 21 2026

The forecast area will remain in the interface region between a strong subtropical ridge axis centered to our southwest and an unseasonably strong longwave trough over the central/eastern CONUS. Northwest flow between these prominent features will support additional rounds of storms as we go through work week. Expect a significant longwave pattern change by next weekend with the trough shifting to the western CONUS while the subtropical ridge builds northward across much of the eastern CONUS. This will result in the potential for stifling heat.

For Today: Patchy areas of dense fog have developed and will continue to around daybreak given the very moist near surface humidity, mostly clear skies, and light wind. Once the fog dissipates, a strengthening low level warm advection pattern will support hotter conditions along with disorganized, diurnally enhanced showers and storms.

Monday through Saturday: Guidance continues to settle on a consensus for more suppressed westerlies, and this will result in continued storm threats with additional concerns for flash flooding/severe weather through this week. As of now, it does not appear any of these threats will be significant, and limited/marginal categories should mostly cover the threats.

With that said, local mesoscale influences and antecedent conditions will drive any flash flood and severe weather threats on a daily basis, so monitor for updates as we go through time this upcoming week. With up to 30 knots of deep layer west- northwest flow that is mostly parallel to weak surface boundaries, there maybe a tendency for multicell storm clusters to back build and train repeatedly for a localized heavier rain flash flood threat. During peak heating, expect updrafts to be intense enough for a marginal severe wind threat.

Heat is increasingly a concern with an elevated threat for Monday ahead of storms that move in later in the day and evening. Going beyond Monday and through the remainder of the work week, heat stress will be a lingering issue for southern portions of the area in particular, with areas farther north a concern if there is just a slight northward shift in the ridge axis from what is currently forecast. By the weekend, the previously mentioned pattern change could result in an especially hot period as upper level ridging strengthens and combines with the very humid conditions to dangerous heat index values. Will be monitoring for additional heat threat messaging. /EC/

AVIATION

(06Z TAFS) Issued at 1244 AM CDT Sun Jun 21 2026

VFR/MVFR flight conditions under mostly clear skies across sites. Patchy fog will be possible pre-sunrise Sunday, briefly reducing flight conditions to IFR. Once fog dissipates, VFR flight conditions are expected ahead of afternoon convection. /SW/

PRELIMINARY POINT TEMPS/POPS

Jackson 88 75 91 75 / 70 10 40 40 Meridian 87 75 92 74 / 70 10 30 30 Vicksburg 88 76 91 76 / 60 10 30 40 Hattiesburg 89 76 93 76 / 60 10 10 10 Natchez 89 76 92 76 / 50 0 10 10 Greenville 90 75 90 74 / 30 30 70 70 Greenwood 90 75 90 74 / 50 30 80 70

JAN WATCHES/WARNINGS/ADVISORIES

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