Debris Flow — Plumas, California

2023-06-12 to 2023-06-13 · near Halstead Flat, Plumas, California

Event narrative

The California Highway Patrol reported multiple slides mud/dirt/rock on SR 70 east of Twain, completely blocking the roadway.

Wider weather episode

Low pressure over Southern California brought significant amounts of atmospheric moisture northward over the mountains, producing showers and thunderstorms with locally heavy rain and multiple reports of small hail. Heavy rain from thunderstorms over western Plumas County produced more than a dozen small debris flows along State Route 70, blocking the highway. There was also a rock slide with a large boulder at Donner Pass.

View location on OpenStreetMap → (40.0193, -121.0650)

Source: NOAA Storm Events Database, event_id 1106214. Narrative written by the NWS forecast office that issued the report.