May 20, 2013, marks the last time the United States was hit by the worst type of tornado. On that date, a monster EF5 tornado tore a 17-mile path through the Oklahoma City suburbs, creating "40 ...

David McNeese/Getty Images for CNN An aerial view of the destruction caused by the massive tornado that struck areas south of Oklahoma City on Monday, May 20, shows the magnitude of damage left in ...

Many building codes changed after an EF-5 tornado hit Oklahoma in May 2013. Places like Moore have some of the strongest ...

A severe weather threat brings a hail and low tornado risk to parts of Oklahoma as storms are expected Wednesday afternoon ...

Tornadoes are among the strongest and deadliest types of weather, capable of destroying entire neighborhoods in minutes. However, the most powerful tornadoes, classified as EF5, make up less than 1% ...

Oklahoma tends to see the most tornadoes during the months of April and May, according to the Storm Prediction Center. Here are the average number of tornadoes each month in Oklahoma: About 70% ...

Tornadoes and hail are possible with a severe storm risk that's expected to move into parts of Oklahoma on Wednesday.

May 20, 2013, marks the last time the United States was hit by the worst type of tornado. On that date, a monster EF5 tornado tore a 17-mile path through the Oklahoma City suburbs, creating "40 ...