WICHITA — A convoy of more than 40 cars and trucks carrying more than 80 scientists and crewmembers will travel across the Great Plains from now to June 13, searching for tornadoes.
The tornado hunters are part of VORTEX2, the largest-ever research project aimed at finding out more about what causes these killer storms — and how to give people earlier and more accurate warnings, says Karen Kosiba, a senior research meteorologist with the Center for Severe Weather Research, in Boulder, Colo.

On average, about 1,000 tornadoes form in the USA each year, killing about 60 people, according to the federal Storm Prediction Center in Norman, Okla.

The original VORTEX study in the mid-1990s helped inspire the Hollywood film Twister. VORTEX is an acronym that stands for Verification of the Origins of Rotation in Tornadoes Experiment.

"We're looking for stronger, more violent tornadoes, and those are relatively rare," Kosiba says.

Tornado warnings average 13 minutes of lead time, and those come with a 70% false alarm rate, according to VORTEX2 planning documents. The researchers want to know whether warning times can be more accurate and whether warnings could be issued a half-hour or more before the storm strikes, Kosiba says.

Among the missions for the severe weather center is deploying "tornado pods," instruments that collect data such as temperature, relative humidity and wind in a storm, says Joshua Wurman, president of the Center for Severe Weather Research.

On Friday, Day 6 of the 35-day project, a steady stream of Kansans posed for pictures here with the tank-like Tornado Intercept Vehicle (TIV), a creation of documentary filmmaker Sean Casey, who hopes to film inside a tornado. Among the curious were Theresa Stensaas, 51, who snapped a photo of her 4-year-old grandson, Alec Metro, standing in front of the vehicle.

"We're farmers, so we rely strictly on our weather alert," she says, "so if we're not in the house, we're out of luck."

Stensaas has firsthand experience with the destructive power of tornadoes. A twister destroyed some silos and farm buildings on the family farm near Concordia, Kan., during Memorial Day weekend four years ago, she says.

The VORTEX2 team hasn't intercepted a tornado this spring, but data collected from several non-tornadic storms could be useful, says Adam French, 26, a North Carolina State graduate student working on the study. The information can help scientists understand the difference between the two types of storms, he says.

On average, about one of every 100 thunderstorms in the USA produces a tornado, according to the Storm Prediction Center.

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