May 11 marks a solemn double milestone in Texas weather history: the state’s deadliest tornado — and its strongest.

Both events observed three EF5/F5 tornadoes, but one difference is that the April 27th event saw one more EF4/F4 than in 1974.

Preliminary ratings for those tornadoes are expected to be finalized in the coming weeks. But you may have seen two different phrases for tornado “ratings,” EF and F. But what is the difference?

Incredibly, nobody was killed in this tornado, but 12 were injured. Oakfield remains one of only three F5 (or EF5) tornadoes on record in Wisconsin and the only known F/EF5 U.S. tornado to have ...

Preliminary ratings for those tornadoes are expected to be finalized in the coming weeks. But you may have seen two different phrases for tornado “ratings,” EF and F. But what is the difference?