IOWA — Sunday marks the five-year anniversary of the Midwest derecho, now known as the most expensive thunderstorm event in modern U.S. history.
Event Overview
- On August 10, 2020, a powerful derecho—a fast-moving, long-lived line of thunderstorms—swept from southeast South Dakota into the Ohio River Valley, carving a 700–770 mile (1,100–1,240 km) path across the Midwest.
- The storm’s duration lasted approximately 14 hours, with sustained damaging winds lasting 30–60 minutes in some locations, far longer than typical derechos.
NEXRAD radar composite as the storm advanced across the upper Midwest.
…
Wind Speeds & Damage
- Measured gusts reached 126 mph in Atkins, Iowa, with damage estimates up to 140 mph…