A scene from Oklahoma last Friday
Brian KhouryA scene from Oklahoma last Friday.

Not only did Friday’s tornado outburst in Oklahoma lead to at least 20 deaths, but analysis by NOAA has revealed that it included the widest tornado ever recorded in the U.S. and one twister that spun the wrong way.

The diameter of the El Reno tornado, which on Friday killed three famous weather chasers, reached a mind-boggling and record-breaking 2.6 miles. Both the El Reno cyclone and the Moore tornado, which struck nearby a week earlier, were rated EF5, the most damaging type of cyclone on the Enhanced Fujita scale. From LiveScience:

“To have two EF5s within less than two weeks in the same general area — that’s highly unusual,” [University Corporation for Atmospheric Research scientist Jeff] Weber told LiveScience. “Off the top of my head, I haven’t heard of it happening before.”