The 1974 Super Outbreak is still considered the benchmark for tornado super outbreaks.
The only other tornado super outbreak to come close happened in 2011. It spawned more tornadoes, but April 3-4, 1974 had more big tornadoes.
In 1974, there were a total of 148 tornadoes touching down in 13 states over the course of two days in early April. Of those 148 tornadoes, 23 were F4's and 7 were F5's — the biggest and worst tornadoes on the Fujita scale with winds blowing at least 207 miles per hour.
These tornadoes left hundreds dead, thousands injured and leveled entire communities.
Back then, the National Weather Service could hardly see green blobs on their radar outputs, and many times had to wait for visual confirmation before issuing a tornado warning.
Now, Doppler radar and big investments into the National Weather Service have enabled today's forecasters to issue tornado warnings an average of 11 minutes ahead of time.
Many parts of the United States have already seen some severe thunderstorms this year, and as the severe weather season heats up, meteorologists will be on the lookout for small outbreaks consisting of one or two tornadoes and the next super outbreak that may finally dethrone 1974 as the worst outbreak to ever hit the country.