Debris Flow in Gunnison County, Colorado

The Colorado Department of Transportation reported a closure along US Highway 50 roughly 10 miles east-southeast of Waunita Hot Springs, in Gunnison County. This area is on the climb up to Monarch Pass, meaning it is an area of very steep terrain that can be prone to rock and mudslides with heavy rainfall. The road had to be briefly closed for cleanup of the debris.

Plenty of monsoonal moisture was present in western Colorado on August 13th, which did lead to a slow start of convection thanks to morning cloudiness. However, once skies cleared, ample instability and some additional lift from a passing jet streak helped to create widespread showers and thunderstorms over the higher terrain. With the abundance of deep, tropical moisture, training or slow moving storms weren't necessary to create flooding and debris flow concerns, and indeed on this day storms moved fairly quickly and did not train but debris flows still occurred. Ultimately, all it takes to create issues during such a setup is steep, susceptible terrain and one storm with high rainfall rates over that location.