Night of the Twisters by Ivy Ruckman

In June of 1980, Grand Island, Nebraska was hit by seven tornadoes in a period of three hours. Night of the Twisters is based on this event. Most of the story follows two boys who are alone in the house when the storms hit. The house is demolished, but the boys survive and now must try to find the rest of their families and help in rescuing their neighbors. A real page-turner.