Day 4-8 Convective Outlook

Issued: 2026-07-07 09:08 UTC  ·  Valid: 2026-07-10 12:00 – 2026-07-15 12:00 UTC

Summary

Organizing storm clusters that could produce damaging wind gusts may develop from the central Canadian border through the Great Lakes and into the Northeast early next week. Severe weather probabilities for these events remain low at this time.

Product Text

000 ACUS48 KWNS 070908 SWOD48 SPC AC 070906 Day 4-8 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0406 AM CDT Tue Jul 07 2026 Valid 101200Z - 151200Z CORRECTED FOR SPELLING ...DISCUSSION... Medium-range model output continues to indicate the evolution of an increasingly prominent mid/upper high across the lower Colorado Valley and Plateau late this week into next weekend. It appears likely that this will continue expanding and encompassing a significant portion of the interior U.S. by early next week, as an evolving larger-scale trough begins to dig across and southeast of Hudson Bay. While there appears relatively small spread within and among the various model output concerning this larger-scale evolution, there is considerable spread concerning the migration of one particularly notable short wave trough around the periphery of the ridge. Of particular concern, it appears probable that a plume of very warm elevated mixed-layer air will advect along the southern fringe of a belt of intensifying flow around the northern through northeastern periphery of the mid/upper ridge. As it does, coupled with low-level moistening, this type of regime could support the periodic evolution of organizing clusters, potentially including one or two potentially long-lived, accompanied by swaths of damaging surface gusts. It appears that this could focus anywhere from near and north of the central Canadian/U.S. border vicinity through the Great Lakes into the Northeast by early next week. However, due to lingering uncertainty with the synoptic developments, and the generally low predictability of these mesoscale systems, in this type of regime at this extended range, severe probabilities still appear less than 15 percent. However, depending on model trends, this could change in later outlooks for this period. ..Kerr.. 07/07/2026