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St. Louis Tornado Is Year's Strongest

st. louis tornado damage picture
The St. Louis EF-4 tornado: Before and after. (Image credit: NWS.)

Good Friday saw the year's strongest tornado yet pound St. Louis, flattening houses and shredding the roof of a crowded airport terminal on its 22-mile path (35 kilometers) along the ground.

Shattered glass injured several people at Lambert-St. Louis International Airport April 22, but no one was reported killed.

The tornado rated the second-highest level on the Enhanced-Fujita tornado damage scale, EF-4, a first for this year's tornado season. The twister, with 200 mph winds (322 kilometers per hour), was the strongest in Missouri's St. Louis County in 44 years.

It was the latest exhibition of wild tornado weather this April, including triplet tornadoes and record numbers of outbreaks.

Aggressive April

The Weather Channel has reported the confirmation of 292 tornadoes so far this month, besting the previous April record of 267 in 1974. The average for April is only 116, according to the Storm Prediction Center in Norman, Okla.

Along with amazing videos of twin and even triplet tornadoes have come new tornado records in several states.

In North Carolina, 28 tornadoes have been confirmed so far for April 16, a record outbreak for any single day there.

In Wisconsin, 14 tornadoes struck on April 10, the biggest outbreak for any April day in the state's history.

Comparing the number of tornadoes from year to year isn't an exact comparison. There seems to be an increase in the number of tornadoes since recording began in the 1950s, but the Storm Prediction Center says that upward trend is mostly due to more people reporting tornadoes, or more buildings being hit as the country's population grows and its cities and towns expand.

Storm survey teams continue to assess the damage from this month's storms, and the tornado counts could change.

Few killers

Remarkably, no one was killed Friday by the invisible, rain-wrapped tornado near St. Louis, and an expert credits advanced warnings.

In most cases, people had more than 30 minutes notice that the tornado and a smaller one were coming, enough time to gather the kids and seek safe shelter, said Mike Smith, chief executive officer of Weather Data Services, a part of AccuWeather.

"I believe more than 100 lives were saved by the warning, because of the density of the population and the length of the tornadoes' paths," Smith told OurAmazingPlanet.

Tornadoes have killed 41 people so far in 2011, only four fewer than the death toll for all of last year. More than half of this year's fatalities were people in mobile homes.

North Carolina has suffered the most this year, with 26 deaths. That's the deadliest outbreak since the "Super Tuesday" storms in February 2008, when 57 people died in Dixie Alley, the southeastern extension of Tornado Alley.

In 2008, during a season among the all-time highest for number of tornadoes, 126 people were killed.

Email OurAmazingPlanet staff writer Brett Israel at bisrael@techmedianetwork.com. Follow him on Twitter @btisrael.

Brett Israel was a staff writer for Live Science with a focus on environmental issues. He holds a bachelor’s degree in biochemistry and molecular biology from The University of Georgia, a master’s degree in journalism from New York University, and has studied doctorate-level biochemistry at Emory University.