Predicting Old Faithful

A park ranger with a stopwatch looking out the window of a visitor center at Old Faithful erupting
Park Ranger Phil Officer predicting an Old Faithful eruption.

Old Faithful has been a top attraction of Yellowstone since the park was established nearly 150 years ago. After each Old Faithful eruption, rangers predict when the next one will be. From over 100 years of recording data, we know if an eruption is longer than 3 minutes, it will be 95 (+/- 10) minutes until the next eruption. If it's under 3 minutes, then it will be 66 (+/- 10) minutes until the next eruption.

"People come from around the world to see Old Faithful, and I help facilitate that. It's a fun part of the job. Seeing a person's reaction to Old Faithful for the first time never gets old." - Ranger Phil Officer

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Last updated: September 24, 2020

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