The Big Thompson Flood 50 Years Later

Remembering the past. Modernizing for the future.

On July 31, 1976, Colorado experienced one of its worst natural disasters when the Big Thompson River Basin between Estes Park and Loveland flooded due to an extreme amount of precipitation falling over the area in a short period of time. This unexpected flood caused a massive amount of damage and a large loss of life. Here the NOAA Probable Maximum Precipitation Estimation Modernization team looks back at this historic event and then looks ahead at the NOAA PMP and Atlas 15 initiatives that advance extreme precipitation understanding, estimation, and prediction capabilities as part of NOAA's mission to protect life and property.

Scroll through the window below for a dynamic story experience. You can jump to the specific sections through the top menu that displays after the cover image. You can also view this story in full screen on the NCEI ArcGIS StoryMap page.


Writers

Emily Mutkoski (NCEI*, Cadmus Group), Lydia Churchill (NCEI, Cadmus), Sydney Luce (NCEI, Cadmus Group), Jenny Cox (NCEI, Cadmus Group)

Maps and Graphics

Sydney Luce (NCEI, Cadmus Group), Karina Springer (NCEI, BLN24)

Contributors

Kelly Mahoney (NOAA Research/Physical Sciences Laboratory), Bill McCormick (Association of State Dam Safety), John England (US Army Corps of Engineers), Russ Schumacher (Colorado State University), Jessica Cherry (NCEI), Michael Brewer (NCEI), Jamie Ramage (NCEI, CSS), Bridget Smith (NCEI, Cadmus Group), Marta Block (NCEI, BLN24)

* NCEI: National Centers for Environmental Information

Mahoney, K., Mutkoski, E., Luce, S., Churchill, L., Cox, J. (September 9, 2026). "The Big Thompson Flood 50 Years Later: Remembering the Past, Modernizing for the Future." National Oceanic and Atmospheric Administration National Centers for Environmental Information.

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Page Last Updated: September 10, 2026