textproduct: Jackson

KEY MESSAGES

- A few severe storms remain possible over western portions of the area this evening.

- The potential for heavy rainfall and flooding will need to be monitored for the next several days.

MESOSCALE UPDATE

Issued at 806 PM CDT Tue May 19 2026

Through tonight...

Broad scale ascent, combined with deep moisture and Theta E advection/convergence, is leading to scattered showers and storms across the area. Majority of the convection has struggled and been more of the pulse variety. Any storms that take some northerly propagation the most favorably aligned to the light southerly mean low level bulk shear. Water vapor imagery indicate a broad mesoscale convective vortex (MCV) over the east to southeast TX, which is driving the moist advection into the southeast propagating cold pool. This is keeping continued storm activity, with the highest coverage of colliding boundaries west of the MS River while more isolated coverage to the east. Convective allowing models (CAMs) continue to indicate this will sag to the east-southeast through around midnight, leading to some storms festering through that period. REFS thunder probs persist but continue to go downward after midnight to 1AM, so convection should only be weakening showers as it approaches the Interstate 55 corridor, if that. Lows will be seasonably warm, with some patchy visibility reductions in the Pine Belt and some low stratus overnight through just after daybreak. Updates were shipped out earlier. /DC/

DISCUSSION

Issued at 125 PM CDT Tue May 19 2026

In the near term, the threat for severe weather has diminished some with most guidance showing a more limited shear/thermodynamic environment as a convective system over the ArkLaTex region makes its way toward northwestern portions of our area. The shear/boundary relationship is less than ideal for getting severe weather with this system, however, if storms develop in the increasing low level warm advection during peak ahead of the system, then those storms could move in more favorable direction to take advantage of the low level shear and bring some gusty winds. With all of that said, we've removed the slight risk and trimmed back the marginal risk area some based on the latest guidance.

Looking ahead, an unusually long duration of wet weather is setting up for the foreseeable future as a large and persistent trough to ridge longwave pattern sets up over the CONUS. In the big picture, this will bring our region a steady stream of subtropical moisture with seasonably high precipitable water values, and multiple upper level perturbations that will provide lift and help initiate multiple rounds of convective rainfall. Given that precipitation efficiency will be high, we'll need to monitor for potential heavy rainfall threat areas where deep convection can persist the longest.

SLU CIPS analogs reveal some heavy rainfall analogs from the historic archives that suggest a flash flood threat could evolve based on our current guidance forecasts, but the details are too uncertain as of now to provide formal messaging. Keep in mind that with each day that accumulates significant rainfall, antecedent conditions will become more favorable for a flood threat. Otherwise, it appears the thermodynamic profiles will not be particularly favorable for severe weather concerns given the deep layer moisture and influence from the southeast CONUS. /EC/

AVIATION

(00Z TAFS) Issued at 806 PM CDT Tue May 19 2026

Ongoing showers and storms will persist through around 20/06-08Z Wednesday before anything lingering will be showers at most. Expect stratus to develop overnight, generally MVFR, with most restrictive stratus and some worse visibility reductions/fog (IFR to LIFR) at HBG and PIB after 20/09-13Z Wednesday. Improvements to VFR should occur around 20/14-15Z, with some showers redeveloping before midday. Majority of rain and storm redevelopment will occur after 20/19-21Z and last through the end of the TAF period. /DC/

PRELIMINARY POINT TEMPS/POPS

Jackson 70 86 69 85 / 60 70 60 80 Meridian 71 89 69 87 / 10 40 40 50 Vicksburg 70 84 69 84 / 80 60 70 80 Hattiesburg 70 90 69 87 / 0 50 20 60 Natchez 71 85 70 85 / 70 60 60 80 Greenville 69 83 68 82 / 90 70 60 90 Greenwood 70 84 68 84 / 80 80 60 80

JAN WATCHES/WARNINGS/ADVISORIES

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