Enhanced risk of severe thunderstorms is forecasted this afternoon and evening across northeastern Kansas, southeastern Nebraska, northwestern Missouri, and southwestern Iowa. Threats include a few strong tornadoes, isolated very large hail, and isolated wind damage. Additional severe storms are expected farther south into Arkansas, eastern Oklahoma, and northeast Texas.

Locations:

  • Primary Area: Northeast KS, southeast NE, northwest MO, southwest IA.
  • Secondary Area: Arkansas, eastern Oklahoma, northeast Texas.

Threats:

  • Tornadoes: Including a couple of strong tornadoes in the primary area.
  • Large Hail: Isolated very large hail greater than 2 inches in diameter.
  • Wind Damage: Isolated damaging wind gusts, particularly if storms organize into line segments.

Timing:

  • Peak Activity: Main risk this afternoon and evening.

Discussion

  • Weather Patterns: A complex surface pattern features a cyclone in northern Kansas with a trailing dryline/Pacific front extending into western Oklahoma. A warm front extends from eastern Oklahoma into eastern Kansas. Current storms along the warm front in eastern Oklahoma are showing wind damage and tornado activity.
  • Atmospheric Dynamics:
    • Moisture and Instability: The warm sector across central Kansas is undisturbed, supporting storm development. Assuming sufficient atmospheric recovery post-rain, northeastern Kansas and southeastern Nebraska could see tornadic supercells by this afternoon/evening. Further south, the atmosphere is recovering quickly ahead of the dryline, and it is likely we’ll see another round of storms in an strongly to extremely unstable airmass.
    • Wind Shear: Effective bulk shear exceeding 50 kt and effective storm-relative helicity (SRH) of 200-300 m²/s² will support rotating updrafts and the potential for strong tornadoes. Similar ingredients are in place further south, but storm development is more uncertain.
  • Storm Development: Convective initiation is likely along the dryline from Eastern Nebraska/Northeastern Kansas down to Northeast Texas. These storms will spread northeast in time.

Technical Storm Discussion

In the mid-afternoon, storms should form from Eastern Nebraska down into Northeastern Kansas. Here, the environment is favorable for tornadoes if you can get a robust supercell. That could be an issue given crowded storm modes and likely frequent interactions — but the south/east end of development should still be a favored location.
Further south, from SE Kansas into Eastern Oklahoma, the dryline should light up by the late afternoon in a particularly explosive environment. With ample 3CAPE, strong effective SRH, and moderate wind shear, this location is a favored location for intense supercells with an associated huge hail and tornado risk.
A look at the environment in the southern target reveals a really favorable environment for even a strong tornado — but the limitations on this will be storm mode, and a more subsident airmass aloft. This may temper overall updraft strength even with strong to extreme instability. Still the low LCLs have this author concerned that today could be sneaky robust in Eastern Oklahoma and SE Kansas given the intense focus to the north.