Thunderstorm Wind in Jerauld County, South Dakota

An extended period of damaging thunderstorm winds was measured by a Road Weather Information System sensor near Lane. The first severe wind gust of 62 mph occurred at 1344 CST, with a peak wind of 81 mph at 1348 CST.

In response to a subtle short-wave aloft, a cluster of thunderstorms moved along the North Dakota-South Dakota border during the early morning hours of July 20, and then slowly expanded to the south as it pushed east. By early afternoon, northern portions of the cluster weakened, while southern portions intensified as it encountered an environment of higher instability and shear. Damaging wind gusts developed across Jerauld and Sanborn Counties with estimated wind gusts up to 90 mph. The town of Woonsocket, South Dakota was particularity hard hit, with significant tree and structural damage across the city. A National Weather Service survey of drone images determined the damage to be a result of severe downburst winds.