On July 21, 1987, an F4 tornado tracked 24 miles across the Teton Wilderness into Yellowstone National Park. Over 1,000,000 trees were knocked down as the tornado slashed its way across mountain tops up to 10,000 feet high, and through valleys. This is the highest altitude in the US that a violent tornado (F4/F5) has ever occurred.
This is a premium article. Sign up for an account today to view this article.