Scientist Identifies Rare High-Altitude Tornado in Wyoming

Winds that leveled 15,000 acres of timber high in the mountains of northwest Wyoming were caused by a rare high-altitude tornado, a leading researcher says.

“This is the highest-elevation tornado, probably, in history,” Theodore Fujita of the University of Chicago said Thursday.

Fujita, widely known in the scientific community for developing the tornado-measuring scale that bears his name, made the remark after examining photographs taken by staff members he sent to survey the destruction.

Officials of the Bridger-Teton National Forest initially speculated that the July 21 winds were produced by a microburst--a sudden, intense downward blast of air that often threatens commercial aircraft with wind shear.

But Fujita, who discovered the existence of microbursts in 1975, disagreed.

“We haven’t got the whole picture yet, but it was not a microburst. It was a tornado,” he said. “My immediate suspicion was that this could be a downburst. However, it was not.”

Fujita said the tornado touched down high in the Rocky Mountains and crossed the Continental Divide at a point above timberline before uprooting trees in an area 20 miles long and up to two miles wide, snapping and scattering tens of thousands of tree trunks.