Twister chase pays off

The most ambitious study of tornadoes ever — five weeks of storm-chasing by about 100 scientists and college students — ended with just one tornado documented.

But no one is calling the effort a failure.

And researchers are crediting Nebraska with providing the most extensive data during the study that concluded over the weekend.

“We only saw one tornado, but that was described as A-plus,” said Susan Cobb, a meteorologist with the National Oceanic and Atmospheric Administration. “It couldn’t have gone any better.”

The tornado, which occurred in far eastern Wyoming, is the first to be documented through its entire life cycle.

“That will be invaluable in improving warnings because we’ll know what conditions caused it to form,” Cobb said Monday.

The goal of the study, called VORTEX2 for Verification of the Origins of Rotation in Tornadoes Experiment 2, is to figure out why certain storms develop into tornadoes so that forecasters can issue more accurate warnings with greater lead time.

Currently, about three-fourths of tornado warnings turn out to be false.

The tornado, which occurred June 5 in Goshen County, Wyo., has been classified as an F2 on the Enhanced Fujita Scale. It lasted about half an hour and didn’t cause serious damage, ending about five or 10 miles west of the Nebraska border.

The storm that spawned the tornado continued into Nebraska, and researchers followed it.

Between following that storm system into Nebraska and tracking a number of others in the state, researchers ended up gathering more data in Nebraska than any other state during the five weeks, from May 10 through June 13, said Don Burgess, a research scientist from the University of Oklahoma and member of the VORTEX2 steering committee.

The study spanned a nine-state area from Texas in the south to South Dakota in the north.

Burgess and Cobb said Nebraska data was collected near Ogallala, Sidney, Alliance, North Platte, Grand Island, Fairbury, Kearney, Alliance, Mullen, Kimball, Scottsbluff, Falls City and Auburn.

That Nebraska would yield so much data is not surprising, Burgess said, because of the state’s location in the heart of the Plains and the fact that Nebraska was entering into its peak time for tornadoes. The researchers had the bad luck of searching for tornadoes during one of the quietest tornado years since the early 1990s.

“There were quite a few days where we had wall clouds, but they just didn’t drop tornadoes,” Cobb said.

Preliminary results will be available this fall, Cobb said, and researchers will continue to analyze the data for years to come.

Burgess said if the last VORTEX study, which occurred in the mid-1990s, is an indication, more accurate tornado warnings should be about three years or so away.

Next spring, the VORTEX2 team will return to the field, for the final leg of the two-year study effort.

During that effort, the University of Nebraska-Lincoln’s research team expects to deploy its remotely operated hobby-style airplane. The plane will fly near, but not into, a tornado, gathering data.

Cobb said it was disappointing for the VORTEX team to not encounter more tornadoes, but since the goal of the study is to understand why tornadoes form, scientists will be able to learn from the storms that didn’t produce tornadoes.

Contact the writer:

444-1102, nancy.gaarder@owh.com