Tornado outbreak and derecho of April 4–5, 2011
From April 4–5, 2011, a large-scale damaging wind event and tornado outbreak affected the Southern and Eastern parts of the United States. The system produced a large serial derecho windstorm that caused thousands of reports of wind damage and several embedded tornadoes.
Source: Wikipedia — Tornado outbreak and derecho of April 4–5, 2011 (CC BY-SA 4.0)