Remembering the Super Outbreak

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It was 40 years ago that the United States suffered the worst tornado outbreak of the 20th century.

The "Super Outbreak" started at 1:00 pm on April 3rd and didn't end until 24 hours later. That system spawned 148 twisters in 13 states, including Indiana.

The combined length of all the tornadoes was approximately 2,500 miles long with more than 300 fatalities and 5,000 injuries. In all, the storms left behind $600 million in damage - and that's in 1974 dollars.

On that day in Indiana, at least 20 tornadoes struck. Some 49 people died across the state and 768 were hurt. In all, 39 counties had damage.

The most destructive cells of that storm including the longest path was called the Monticello Tornado family. It produced a series of nine tornadoes across Illinois and Indiana and included a 109-mile long path with a width of up to a half mile. That outbreak prompted research and new technology that saves lives.

Back in 1974, National Weather Service forecasters could only see green blobs on their radar scopes and had to wait for visual confirmation of the tornado before issuing a warning.

"The tragedy of having tornadoes in 13 states in 16 hours and losing 318 people through those states came out research money that we got to develop better satellites; we got to develop Doppler radar; now we have Google pole radar which helps us indicate tornadoes a lot sooner than they would have back in 1974," said Dan McCarthy, National Weather Service.

Learn more about the outbreak here.