derecho
n.— «On the evening of July 8, cool air made heavy by rain crashed earthward at tremendous speed in central Nebraska, said Pollack, the weather service meteorologist. The descending air touched off a weather phenomenon known as a derecho, he said. The cool air caused the big winds, Pollack said. After it hit the ground, the air spread out, blowing wind in front of the thunderstorms and causing more thunderstorms.» —“Errant Weather Systems Make Misery” by Chris Burbach Omaha World-Herald (Neb.) July 16, 1993. (source: Double-Tongued Dictionary)