Debris Flow — San Miguel, Colorado

2025-10-11 · near Ophir, San Miguel, Colorado

Event narrative

Heavy rain resulted in a rockslide on Highway 45 at mile marker 64.5, about 1 mile north of the Ophir turns between 0900 and 0930 MST. A boulder the size of a small sedan fell on Highway 145, blocking the road. Lanes were reopened by 1030 MST.

Wider weather episode

Between October 10-14, 2025, southwest Colorado experienced prolonged periods of rain and some of the largest multiday rainfall totals on record with rainfall accumulations between 3 and 8 inches, with locally higher amounts across the San Juan Mountains. Remnants from two tropical storms supplied anomalous moisture across the region, with minimal break between events. The first round of heavy rainfall resulted in flooding across La Plata and Archuleta counties from decaying Tropical Storm Priscilla beginning October 10 and continuing throughout the day on the 11th. There was a break in rain across the area on October 12, followed by a second round of heavy rain from October 13-14, associated with moisture from remnant Tropical Storm Raymond. Without much time between systems, the hydrologic response of the second storm was much faster than the first. Flooding across several counties in southwest Colorado spiked twice within the 5-day window, leading to major flooding and near record peaks along the Vallecito, Piedra and San Juan watersheds that lingered through the 16th before water levels receded. Numerous debris flows and rockslides also occurred as a result of the abundant rainfall.

View location on OpenStreetMap → (37.8645, -107.8700)

Source: NOAA Storm Events Database, event_id 1298387. Narrative written by the NWS forecast office that issued the report.