Severe Storm Clusters, Very Large Hail and Flash Flood Risk Sweep Central U.S.

Overview

• The NWS Storm Prediction Center issued Severe Thunderstorm Watch 258 late Sunday night for eastern Kansas and western/central Missouri and Watch 260 early Monday for west central Illinois and east central Missouri.
• Forecasters analyzed extreme instability with MLCAPE values above 4,000–4,500 J/kg and 40–50 kt of deep‑layer shear in parts of Kansas, conditions that favor very large hail and strong, damaging wind gusts.
• WPC mesoscale precipitation discussions highlight slow storm motions and training cores producing rainfall rates of 1–3+ inches per hour, making localized to likely flash flooding possible from east‑central Kansas into western Missouri, Nebraska, Iowa and the Dakotas.
• Convective behavior is mixed: some discrete supercells and clusters are consolidating and growing upscale near the I‑70 corridor, which could raise damaging wind risk, while other MCS segments downstream have shown a weakening trend.
• Spotters reported a brief tornado near Madison, Kansas, and forecasters say they are watching corridors near Sioux Falls and Omaha for isolated tornadoes; local NWS offices and river forecast centers are coordinating warnings and flood guidance for urban and flood‑prone areas.