The National Weather Service defines derechos as “widespread, long-lived wind storms associated with a band of rapidly moving showers or thunderstorms.” The extreme weather phenomena started in central Nebraska Friday and continued Saturday. Major US cities, such as Kansas City and St. Louis were hit by strong winds and rain. More than 14 states also felt the impact of the storm. Even a weather radar site was struck by lightning as the storms approached. A flash flood emergency was declared for southern Newton and northern McDonald counties in southwestern Missouri.
According the meteorologists, the threat for flooding and violent thunderstorms will continue across the center of the nation into Monday. The large rivers are expected to rise. Incidents of damage to trees, power lines and roofs on account of strong wind gusts and areas of flash flooding can occur. By Monday night the Great Lakes region will confront with an organized storm system.