» 553 people killed, second-highest toll on record. Tornadoes killed 794 people in 1925.
» 748 tornadoes confirmed in April, most on record for any month. Previous record was 550 in May 2003.
» April 14-16 and April 25-28, two largest tornado outbreaks on record.
» 199 tornadoes and 216 people dead on April 27, the most tornadoes on any single day and the most deaths in a 24-hour period.
» 158 people killed and $3 billion in damage on May 22 in Joplin, Mo., passing previous records for a single tornado in the modern era of record-keeping, from 1950 to the present.
» 1,625 tornadoes confirmed, a near record, with dozens yet to be confirmed.
» $28 billion in damage, the highest in a single year since record-keeping on damage began in 1980.
Source: National Climatic Data Center
Key ingredients are in place for a stormier-than-normal spring, accompanied, perhaps, by more tornadoes.
Although the National Weather Service and its sister public agencies don't issue tornado season forecasts, two private weather companies advise that conditions nationally are ripe for a second year of worse-than-normal tornadoes.
Last year was one of the deadliest and costliest U.S. severe weather seasons on record. Tornadoes alone claimed more than 500 lives.
The Midlands received an early wake-up call last year when a tornado struck Mapleton, Iowa, on April 9, damaging about a third of the town. Although a number of people were injured, no one was killed.
A La Niña climate pattern added power to last year's storms, and this year again La Niña could play a role, albeit a lesser one, meteorologists say.
Factors in play, according to AccuWeather Inc., The World-Herald's private weather consultant, and Telvent DTN:
» Warmer-than-normal waters in the Gulf of Mexico are poised to send a supply of warm, moist air northward, setting up potentially violent clashes with cold air from the north and dry air from the desert Southwest.
» A La Niña in the Pacific Ocean increases the odds that an active storm pattern will travel through the nation's midsection (Tornado Alley) instead of farther south, as typically happens during the opposite climate pattern, El Niño. La Niña arises from cooler-than-normal waters in the Pacific Ocean.
While the odds favor a greater number of tornadoes this year, that doesn't mean they will repeat with last year's deadly results, said Jeff Johnson, chief science officer for Telvent.
"Some of last year was just a bit of bad luck," he said. "Some of those storms happened over populated areas. Most years they pass over largely rural areas."
Greg Carbin with the U.S. Storm Prediction Center in Norman, Okla., said there's a reason why the federal government doesn't issue tornado forecasts but does so for hurricane seasons. Hurricanes are, in general, more predictable. They're larger, and the science is more mature.
Both Carbin and Brian Smith of the weather service office in Valley said the science on tornadoes hasn't yet gelled.
Carbin said other weather factors could mute the power of La Niña and warm Gulf of Mexico waters. An early summer, for example, would sap strength from the storm track, he said.
Smith said questions about tornadoes are a familiar refrain.
"I get asked the same thing every year, 'What is this year going to be like?' The problem is everything depends upon storm track," Smith said. "To get a tornado, you need to have the right ingredients at just the right time. Timing is everything."
AccuWeather is projecting that the worst of this year's tornado season will most likely target the Ohio Valley and mid-Mississippi Valley.
"Areas that seemed to miss out on frequent severe weather last year may see an uptick this year," said Dan Kottlowski, a senior AccuWeather meteorologist.
Iowa and Nebraska could end up with a more typical year, according to AccuWeather, but Johnson, of Telvent, wasn't ready to write off the possibilities.
"You can't really get specific like that," he said. "This broad seasonal forecast means a large area, which includes the Omaha area, is at a greater risk of seeing these more destructive storms."
But where tornadoes occur is more important than the number. That was evident in 2004, when a devastating tornado hit Hallam, Neb., and in 2008, the year of the Little Sioux Scout Camp tornado.
Smith, warning coordination meteorologist for the weather service office that serves the Omaha area, said deadly weather can occur without a tornado.
With severe weather season around the corner, now is the time for families to prepare.
That means clearing out a spot in the basement and developing a pre-determined plan on what to do when severe weather strikes.
Tornadoes can happen any month of the year — and in some years the season in the Midlands gets an early start in March, he said. Tornado activity in the Midlands picks up in earnest in April and peaks in May and June, he said.
Contact the writer:
402-444-1102, nancy.gaarder@owh.com
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