3 spring tornadoes make deadliest list - KSLA News 12 Shreveport, Louisiana News Weather & Sports

Deadliest Tornadoes since 1947

Sources: NOAA and the National Weather Service

3 spring tornadoes make deadliest list

An EF-4 tornado touched down in the college town of Tuscaloosa, AL, killing 43. The tornado then trekked east toward Birmingham, Alabama's largest city. (Source: NOAA) An EF-4 tornado touched down in the college town of Tuscaloosa, AL, killing 43. The tornado then trekked east toward Birmingham, Alabama's largest city. (Source: NOAA)
Joplin, MO, was leveled by a tornado that killed 153 people on May 22. (Source: CNN) Joplin, MO, was leveled by a tornado that killed 153 people on May 22. (Source: CNN)

(RNN) - Three of the top seven deadliest tornadoes in the past 64 years all occurred within one month of each other, making the months of April and May two of the deadliest months for tornadoes in six decades.

Meteorologists say the high death tolls can be blamed on a variety of factors, including particularly violent weather conditions, the storms striking more densely populated cities and longer time on the ground.

"We've had more significant tornado events in this year than we've had in the past generation or two," said Greg Carbin, with the National Oceanic and Atmospheric Administration Storm Prediction Center. "It's hard to put in any kind of real context because it's so far out there."

Scientists are still trying to determine what factors led to the storm systems that spawned the three most violent weather systems so far this year.

The tornado outbreak that thundered across seven states on April 27-28 spawned two particularly deadly twisters in Alabama - one in Hackleburg that killed 78 people and another in Tuscaloosa-Birmingham that killed 63.

The Hackleburg tornado was rated an EF-5 – the worst and most destructive type of tornado – and stayed on the ground for 90 miles, destroying almost everything in its path. More than 37,000 homes were destroyed in Alabama on that day.

Less than one month later, Joplin, MO, was flatted by a May 22 tornado. It is the deadliest storm on record since April 1947, killing 153 people. The three-quarter-mile-wide tornado was on the ground for 6 miles, destroyed a local hospital and sucked victims from the houses and cars in which they hid.

So far, 536 people have lost their lives due to tornadoes this year.

More victims in the path

The unusually violent season has left meteorologists in overdrive. What makes this year different than most – besides the numbers of casualties – is that these storms seem to have gravitated toward population centers.

Harold Brooks, who works with the NOAA National Severe Storms Lab, explained that most people are accustomed to tornadoes striking in areas with more sparse populations, such as Oklahoma, which has a population distribution of about three persons per square mile.

More densely populated areas in the East, such as in the suburbs of Massachusetts, where a tornado touched down on June 1 and killed four people, usually have about 25 people per square mile.

"We've had more strong tornadoes than we do in most years, but a large component is those tornadoes going through populated areas," Brooks said.

The twisters also have stayed on the ground longer.

So-called "long track tornadoes" carve up several miles on the ground, and play a seemingly contradictory role in saving lives and taking them.

Brooks said there have been several storms this year, such as the May 24 tornado west of Oklahoma City that killed 10 people, that "meteorologically were not all that different" from the mega-killers this year, however the Oklahoma City tornado had a much shorter path.

In other words, the tornadoes packed a similar punch. But the Alabama tornadoes stayed on the ground longer, causing more deaths.

"You had a couple of tornadoes on the ground for a long time in very populated areas," Brooks said.

More time to warn

However, Carbin says those long paths can be an asset.

Though very dangerous, their time on the ground can buy time to build awareness for those in its path.

"Here in Oklahoma, you can go back to May '99, [a tornado] moved into a densely populated area but it moved in an hour after it had been followed by a news chopper," he said. "Once the storm is on the ground and is well documented, the longer you have to know that it's moving in your direction and the more likely you are [to take cover]."

Still, some are pointing to that time on the ground as one of the reasons some people chose not to evacuate until it was too late.

Storm forecasters and emergency management personnel walk a fine line between giving people enough time to evacuate and giving them a false sense of security because they can't actually see what they're being told is coming their way until it may be too late.

For NOAA, this season sharpens their focus on finding swift and effective ways to relay serious storm warnings without creating panic.

"All of our capability in terms of forecasting and warnings and sirens, what it really comes down to is, we can't change the intensity and violence of nature. There is nothing anybody can do about where tornadoes are going to go," Carbin said. "With that in mind, we have to get across to people that situational awareness."

No easy answers

The outsized and death and destruction of this tornado season understandably makes people question "why," and attempt to find a pattern among the deadliest of the twisters.

It may be some time – if ever - before meteorologists are able to determine why so many intense storms have formed this year.

The Tuscaloosa and Joplin tornadoes, if they were to occur "singularly" in one season, would be remarkable, Carbin said. But to have them occur back-to-back is tragic.

"A lot of ways the answer is bad luck with some meteorology in it," he said.

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