“PDS watches with severe thunderstorms are rare and only for the strongest thunderstorm events,” said CNN meteorologist Brandon Miller. “Gusts of wind are projected to reach 100 miles per hour with thunderstorms as they roll through northern Illinois and southern Wisconsin.”
A gust of wind 106 mph in Marshall, Iowa, was reported as the storm passed.
Derecho (pronounced similarly to “deh-REY-cho”😉 is a long-lasting, large-scale wind storm involving a rapidly moving band of showers or thunderstorms.
This storm complex is located in the same area, with moderate risk (level 4/5) of severe storms. SPC upgraded this risk on Monday afternoon due to the formation of negative signals. The risk area includes more than 13 million people.
In addition to wind damage, a heavy hail – an inch and a half in diameter – can result – and several tornadoes can occur.