The tornado that struck El Reno, Okla., Friday "is officially the widest known tornado in the U.S.," says the National Weather Service office in Norman, Okla., announcing today that at its widest, the ...

The deadly cyclone that struck on Friday in El Reno, Oklahoma, was the second EF5 tornado in less than two weeks to wreak devastation on the state. It was also the largest twister ever recorded in the ...

After weeks of engineering analysis, informed largely by a new technique developed by Western's Canadian Severe Storms Laboratory (CSSL), a tornado ...

The deadly tornado that ripped through rural Enderlin, North Dakota, in June has been upgraded from EF4 to an EF5, making it ...

The first EF5 tornado was confirmed in North Dakota, here's a history and the last F5 tornadoes to hit Michigan.