Debris Flow in Ouray County, Colorado

Heavy rainfall resulted in mudslides along Highway 550 at mile marker 101.5, approximately 2 miles south-southeast of Ridgway. About an inch of storm total rainfall was reported in Ridgway with this event. Daily spot forecasts were requested by emergency management for both Ridgway and Ouray for extensive cleanup efforts for several days following the debris flows.

Deep monsoonal moisture remained in place with convection ongoing during the morning hours. This led to a later start to convection on the afternoon of August 11th but precipitable water values climbed to over an inch as deep monsoonal moisture continued to increase from the south, combined with a shortwave trough and sufficient lift from an upper level jet helped provide support for stronger storms towards the late afternoon and evening that led to 1 to 2 inch per hour rainfall rates on top of already saturated soils leading to significant debris flows and flash flooding, especially across southwest Colorado.