It doesn’t happen very often, but Colorado had a rare mountain tornado touchdown near Mt. Evans. Saturday afternoon at 2:51 pm. Thunderstorms strengthening over the mountains west of Denver were strong enough to produce a weak, short-lived twister. The National Weather Service has analyzed pictures from the area and confirms that it was a bona fide tornado.
Typically, these types of storms can produce what are known as cold air funnels. Which are not tornadoes but do develop from cold air pooling in the upper levels of a thunderstorm. And with differing temperatures at altitude wind shear can cause a funnel-shaped cloud to drop from a thunderstorm. These funnels tend to be very weak and almost never touch the ground.
But in this situation the air entering the bottom of this Mount Evans storm was warm enough to produce a tornado touchdown. The National Weather Service is estimating this to be the second highest tornado ever recorded in the United States. The spot where the touchdown occurred to be roughly at 11,900 feet.
It is estimated that the highest recorded tornado in the U.S. happened in 2004. On July 7 of that year, at 12,000 feet a hiker took a picture of a tornado in Sequoia National Park in California.
Source: CBS Denver