Day 3 Convective Outlook

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Issued: 2026-09-09 06:25 UTC  ·  Valid: 2026-09-11 12:00 – 2026-09-12 12:00 UTC

Summary

Severe thunderstorms capable of producing large hail and damaging wind gusts are possible across portions of the Upper Midwest into Nebraska late Friday afternoon through Friday night.

Product Text

000 ACUS03 KWNS 090625 SWODY3 SPC AC 090624 Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0124 AM CDT Wed Sep 09 2026 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE MID-MISSOURI VALLEY INTO THE UPPER MIDWEST... ...SUMMARY... Severe thunderstorms are possible across portions of the Upper Midwest late Friday afternoon into Friday night. ...Upper Midwest into Nebraska... An upper shortwave trough will move across the northern Plains and Upper Midwest on Friday. This will result in enhanced westerly flow and cooling aloft across the region, mainly after 00z. A surface cold front is forecast to develop southeast across the Dakotas through the afternoon, and continue east/southeast across the Upper Midwest and portions of the central Plains through the nighttime hours. Southerly low-level flow will transport 60s dewpoints northward across the MO Valley into MN ahead of the front. Northward advection of low-level moisture beneath cooling aloft/steepening midlevel lapse rates will lead to at least a narrow corridor of moderate destabilization during the late afternoon into evening from central/eastern NE into MN. Stronger large-scale ascent and vertical shear will be focused across MN. With southward extent, instability may be greater, but shear and large-scale ascent will be weaker. Additionally, warmer midlevel temperatures may persist further south, resulting in capping and a more conditional severe risk. Large hail and damaging gusts appear to be the predominant hazard with storms from late Friday afternoon into the nighttime hours. ..Leitman.. 09/09/2026 $$