A tornado touched down at about 2:53 p.m. CDT Monday in Moore, between Norman and Oklahoma City.
Several tornadoes touched down from Oklahoma to Iowa, including near Wichita, Kan., and Oklahoma City, on Sunday.
Slow-moving showers and storms will bring heavy rain and flooding potential.
Reports from Monday's severe weather.
Rising temperatures and humidity across the mid-Atlantic will have it feeling like the end of June.
Heavy rain returning to the northern Plains will generate a renewed flood threat for the Red River.
Ohio Valley (1860)
Tornado swarm in Ohio Valley hit Louisville, KY, Cincinnati, OH, Chilicothe, OH, and Marietta, OH. Damage totalled $1 million; 4 people killed in Cincinnati.
Memphis, TN (1983)
Freak lightning bolt strikes a man in his neck, runs down his spine, and passes out of a pocket containing keys. The bolt then struck 2 other men nearby before also hitting a tree the men were standing under at a golf course. Miraculously all three men survived.
Atlantic City, NJ (1992)
28 degrees -- coldest ever for so late in the season at the airport