Day 4-8 Convective Outlook

Issued: 2026-09-15 08:44 UTC  ·  Valid: 2026-09-18 12:00 – 2026-09-23 12:00 UTC

Summary

The potential for organized severe thunderstorms across much of the central and southern Great Plains through the lower Ohio and Tennessee Valleys remains low through early next week.

Product Text

000 ACUS48 KWNS 150844 SWOD48 SPC AC 150842 Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Tue Sep 15 2026 Valid 181200Z - 231200Z ...DISCUSSION... The latest medium-range model output still suggests that an initially prominent mid-level ridge, across the central and southern Great Plains through lower Ohio/Tennessee Valleys at the outset of the period, will become suppressed late this week into next weekend. But, this may be a bit slower to occur than previous guidance has suggested, and the coinciding and subsequent pattern evolution across much of North America has become more unclear due to model spread. In general, though, it still appears that modest to weak split westerlies will prevail, with little appreciable signal for substantive surface cyclogenesis. Barring appreciable change, the potential for organized severe thunderstorm development still appears low through at least early next week. ..Kerr.. 09/15/2026