Severe thunderstorms are expected this afternoon and evening across parts of the Upper Mississippi Valley, Mid Missouri Valley, Central Plains, and Southern High Plains. Main threats include large hail, damaging winds, and a few tornadoes.

Locations:

  •  Slight Risk Areas: Upper Mississippi Valley, Mid Missouri Valley, Central Plains, Southern High Plains

Threats:

  • Damaging Winds: Strong winds up to 75-80 mph possible.
  • Large Hail: Significant hail, potentially very large in the Central Plains.
  • Tornadoes: A few tornadoes, especially in Minnesota and Southwest Kansas.

Timing:

  • Storm Initiation: Early afternoon in the Upper Mississippi Valley and Mid Missouri Valley.
  • Storm Evolution: Multiple bowing clusters expected late afternoon/evening.
  • Storm Weakening: Likely after midnight.

Discussion:

  • Synoptic Setup: A pronounced upper trough will move eastward across the Northern Plains and Canadian Prairie provinces, with multiple embedded mid-level perturbations moving northeastward.
  • Upper Mississippi Valley: A moist airmass and moderate instability will support storm development along the cold front. Expect robust thunderstorms with large hail and damaging winds, transitioning to a mainly damaging wind threat with time. Low-level shear may support a few tornadoes, particularly in Minnesota.
  • Central Plains: Strong daytime heating will erode the cap, leading to storm development along the front. Supercells with very large hail and possible tornadoes are expected, especially in Western/Central Kansas. Storms will likely organize into a bowing cluster, increasing the damaging wind threat.
  • Southern High Plains: Scattered storms are expected along/east of the dryline, with severe wind gusts as the primary threat.