June 2012 North American derecho
The June 2012 Mid-Atlantic and Midwest derecho was one of the most destructive fast-moving severe thunderstorm complexes in North American history. The progressive derecho tracked across a large section of the Midwestern United States and across the central Appalachians into the mid-Atlantic states on the afternoon and evening of June 29, 2012, and into the early morning of June 30, 2012.
Source: Wikipedia — June 2012 North American derecho (CC BY-SA 4.0)