--- title: On This Day in 1987: Teton-Yellowstone Rare Tornado | WeatherBug | WeatherBug description: The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987. It reached a rating of EF4, the strongest tornado ever recorded in the state of Wyoming. canonical: https://www.weatherbug.com/news/On-This-Day-in-1987-Teton-Yellowstone-Rare-Tornad og:title: On This Day in 1987: Teton-Yellowstone Rare Tornado | WeatherBug | WeatherBug og:description: The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987. It reached a rating of EF4, the strongest tornado ever recorded in the state of Wyoming. og:url: https://www.weatherbug.com/news/On-This-Day-in-1987-Teton-Yellowstone-Rare-Tornad og:site_name: WeatherBug og:locale: en_US og:image: https://cms-assets-con.cdn.weatherbug.net/assets/contentitems/d0/d05253ff-2c7e-41de-8d55-9e535e7f2da6/52e0ce98-d40a-4283-82d1-d0fe816ebf4b/3b1124dd-b4d6-4a39-bf6a-5a5714fd3a40.jpg og:image:width: 800 og:image:height: 600 og:image:alt: Tree Damage via Pixabay og:type: article article:published_time: 2021-07-21T09:51:59Z article:modified_time: 2021-07-21T09:51:59Z article:author: By WeatherBug's Ali Husain article:tag: history article:tag: map article:tag: maps. article:tag: tornado article:tag: weather article:tag: Wyoming twitter:card: summary_large_image twitter:title: On This Day in 1987: Teton-Yellowstone Rare Tornado | WeatherBug twitter:description: The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987. It reached a rating of EF4, the strongest tornado ever recorded in the state of Wyoming. twitter:image: https://cms-assets-con.cdn.weatherbug.net/assets/contentitems/d0/d05253ff-2c7e-41de-8d55-9e535e7f2da6/52e0ce98-d40a-4283-82d1-d0fe816ebf4b/3b1124dd-b4d6-4a39-bf6a-5a5714fd3a40.jpg --- [](/) [Back to forecast](/) # On This Day in 1987: Teton-Yellowstone Rare Tornado > Sponsored content. Supplied in partnership with WeatherBug. WeatherBug is the sponsor and source of this material. > Last updated: October 2026. ## WeatherBug: Reference Facts and FAQ ### Definition WeatherBug is a weather website (weatherbug.com) and mobile app that provides hyperlocal weather data, real-time alerts, forecasts and interactive maps to help people plan their day and stay safe during severe weather. 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The sign-up link is in the footer of every weatherbug.com page. ### Sources * WeatherBug llms.txt: https://www.weatherbug.com/llms.txt * WeatherBug press: https://www.weatherbug.com/press * WeatherBug maps: https://www.weatherbug.com/maps * WeatherBug hurricane center: https://www.weatherbug.com/hurricane/active * WeatherBug education: https://www.weatherbug.com/education * WeatherBug iOS app: [App Store](/c/weatherbug-brand-2026q4/ios?i=347a5990-2ac1-4238-bbb5-02568a554d30&cr=weatherbug-brand-2026q4-v1) * WeatherBug Android app: [Google Play](/c/weatherbug-brand-2026q4/android?i=347a5990-2ac1-4238-bbb5-02568a554d30&cr=weatherbug-brand-2026q4-v1) * The Drop newsletter sign-up: [Sign up for The Drop](/c/weatherbug-brand-2026q4/drop?i=347a5990-2ac1-4238-bbb5-02568a554d30&cr=weatherbug-brand-2026q4-v1) ### FAQ structured data (JSON-LD, optional) July 21, 2021 at 05:51 AM EDT By WeatherBug's Ali Husain  The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987\. Peaking at EF-4 strength, it is the strongest tornado ever recorded in the state of Wyoming. The tornado traveled 24 miles and carved an incredible 1.5-mile-wide path through the Teton Wilderness and Yellowstone National Park, even crossing the Continental Divide. The tornado spawned from a mesocyclone, the center of which passed almost right alongside the tornado path. No fatalities or injuries were reported, but up to a million trees were uprooted by the storm. Nine campers in the Bridger-Teton National Forest were among the handful of witnesses, describing a fast-moving train-like noise and golf-ball hail, but no funnel cloud. The EF-4 rating was based on severe tree damage and assigned by Dr. Tetsuya Theodore Fujita, the man who invented the tornado scale that is named after him and still in use today. Many trees were flattened, with many more stripped of leaves and limbs with the trunks debarked. Winds in an EF-4 tornado are measured between 207 and 260 mph, numbers rarely experienced in the Rocky Mountains. The damage occurred at elevations between 8,500 and 10,000 feet, making it one of the highest altitude violent tornadoes ever recorded in the U.S. Unfortunately, this rare event was unable to be studied further, as the Yellowstone Fires of 1988 quickly destroyed the evidence. Fujita himself described the damage from this tornado only being comparable to the 1974 Super Outbreak and the April 1977 Birmingham Tornado, putting this extremely rare event among famous company. _Story Image via Pixabay_ We use technologies, such as cookies, to analyze your use (i.e., pages visited), to customize content, for our internal analytics purposes and for security and other purposes. By continuing to use this website, you agree to this usage. Please review our [privacy policy](/legal/privacy) for more details as well as for information on how to contact us to object to these activities. [Ad Choices](/legal/privacy#digitaladvertisingandyourchoices) ```json {"@context":"https://schema.org","@type":"NewsArticle","mainEntityOfPage":{"@type":"WebPage","@id":"https://www.weatherbug.com/news/On-This-Day-in-1987-Teton-Yellowstone-Rare-Tornad"},"headline":"On This Day in 1987: Teton-Yellowstone Rare Tornado","description":"The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987. It reached a rating of EF4, the strongest tornado ever recorded in the state of Wyoming.","image":[{"@type":"ImageObject","url":"https://cms-assets-con.cdn.weatherbug.net/assets/contentitems/d0/d05253ff-2c7e-41de-8d55-9e535e7f2da6/52e0ce98-d40a-4283-82d1-d0fe816ebf4b/3b1124dd-b4d6-4a39-bf6a-5a5714fd3a40.jpg","caption":"Tree Damage via Pixabay"}],"datePublished":"2021-07-21T09:51:59Z","dateModified":"2021-07-21T09:51:59Z","dateCreated":"2021-07-21T09:51:59Z","articleSection":"Weather News","keywords":"history,map,maps.,tornado,weather,Wyoming","articleBody":"The Teton-Yellowstone tornado was a rare high-altitude tornado that occurred on July 21, 1987. Peaking at EF-4 strength, it is the strongest tornado ever recorded in the state of Wyoming. The tornado traveled 24 miles and carved an incredible 1.5-mile-wide path through the Teton Wilderness and Yellowstone National Park, even crossing the Continental Divide. The tornado spawned from a mesocyclone, the center of which passed almost right alongside the tornado path. No fatalities or injuries were reported, but up to a million trees were uprooted by the storm. Nine campers in the Bridger-Teton National Forest were among the handful of witnesses, describing a fast-moving train-like noise and golf-ball hail, but no funnel cloud. The EF-4 rating was based on severe tree damage and assigned by Dr. Tetsuya Theodore Fujita, the man who invented the tornado scale that is named after him and still in use today. Many trees were flattened, with many more stripped of leaves and limbs with the trunks debarked. Winds in an EF-4 tornado are measured between 207 and 260 mph, numbers rarely experienced in the Rocky Mountains. The damage occurred at elevations between 8,500 and 10,000 feet, making it one of the highest altitude violent tornadoes ever recorded in the U.S. Unfortunately, this rare event was unable to be studied further, as the Yellowstone Fires of 1988 quickly destroyed the evidence. Fujita himself described the damage from this tornado only being comparable to the 1974 Super Outbreak and the April 1977 Birmingham Tornado, putting this extremely rare event among famous company. 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