High-Impact Weather and Climate Events

A massive, near-stationary thunderstorm dropped up to 12" of rain in 6 hours in Big Thompson Canyon, causing extreme flash flooding. Hundreds of homes were destroyed along Highway 34, and many motorists were trapped. The estimated discharge of 33,000 cfs at the canyon mouth was estimated to be a 300-year event. The most deadly natural disaster in Colorado history.

Flash flood in Dry Creek near Eden swept away a passenger train crossing trestle, causing heavy fatalities. Additional flooding on Fountain Creek.

$1,096,046,204 | Over 9" of rain fell in the Pueblo area, causing extreme flash flooding on the Arkansas River. A bridge collapse in Pueblo caused many fatalities. Related rain events caused flooding and damage on the South Platte River, Coal Creek, Boulder Creek, and St. Vrain Creek.

"Utah's most deadly avalanche occurred in Bingham Canyon. It demolished 14 miners' cottages ... A 3-story boarding house ... and killed 36 people and injured 13 others out of the 65 people that were in its path." - Western Regional Climate Center

Flash flood in Rhode Canyon and Berwind Canyon damaged houses, railroads, and mines; the high-water mark was 30 feet above normal flow in Rhode Canyon.

Multiple convective rain events over a two-day period caused severe to extreme flooding on Monument Creek, Kiowa Creek, and the South Platte River.

Thunderstorm-driven flash flooding in tributaries of Bear Creek (Tucker Gulch, Mt. Vernon Creek, Turkey Creek) and in Clear Creek. Peak discharge in Bear Creek was 8,600 cfs.

"The flood devastated Tucker Gulch in Flood. Residents referred to this flood as the worst ever to hit Morrison. This storm also hit Golden and Eldorado Springs hard. The photo above shows the damage along Tucker Gulch in Golden. The flood waters washed away plenty of bridges, homes, and people. A cloudburst caused flooding along Bear Creek, Turkey Creek and Mount Vernon Gulch. As a result to these flooded creeks, 27 people lost their lives, and a ten foot wall of water roared down Bear Creek." - Mile High Flood District

Moisture from the remnants of Hurricane Linda spread into the Southwest and intersected with a strong upper-level trough, sparking isolated heavy thunderstorms. Two successive storms passed over Hildale between 2:00 pm and 5:00 pm, dropping an estimated 2" in rain. This caused two flood peaks on Short Creek in Hildale, the second of which swept away two vehicles with 16 people inside, 13 of whom drowned. The second storm also produced heavy rain in Zion National Park, about 15 miles north of Hildale, causing a flash flood in Keyhole Canyon that killed seven park visitors who were canyoneering. Another motorist 15 miles west of Hildale was swept away and killed by flooding the same day.

By some measures, this is still the most costly and destructive flood event in Colorado history. Intense thunderstorms near Castle Rock dropped over 14" of rain in several hours, causing extreme flooding on Plum Creek, Cherry Creek and the South Platte River. The flood zone included two-thirds of Denver's industrial area. The Purgatoire River and lower Arkansas River also experienced severe flooding; 11" of rain fell at Holly and over 15" near Lamar in one day.

Heavy rainfall on Plum Creek headwaters caused severe flooding on Plum Creek, Cherry Creek, and the South Platte River.

"At the time of the 1864 flood what was then known as “Denver City” rested on the northeastern banks of Cherry Creek. A snowy winter, heavy spring rain and an unusually violent thunderstorm caused horrendous flash flooding along Cherry Creek. Pioneers had built in the dry bed of Cherry Creek, despite warnings by Arapaho Chief Little Raven. One night a six-foot wall of water came crashing down the creek. The flood killed 15 to 20 people and did an estimated $1 million worth of property damage. Today, American Historian, Dr. Tom Noel, notes, in writing for the Denver Post, “Learning a lesson from that great flood and several others that followed it, Denverites have given Cherry Creek much more room with a walled channel, a greenway and a grassy tree lined boulevard. As Coloradans rebuild, consider giving all our waterways plenty of roomy green space." - Mile High Flood District