Debris Flow — Contra Costa, California

2019-01-17 · near Danville, Contra Costa, California

Event narrative

Mud flow along hillside at Bollinger Canyon Rd just west of Bear Tree Road crossing westbound lanes.

Wider weather episode

A moderate to strong atmospheric river impacted much of California in the middle of the month. A weak surface low developed off the coast on January 15th bringing moderate to heavy rainfall to portions of the region. Over the next 24 to 36 hours a second strong low pressure system moved to the north and east bringing heavy rain, destructive winds, high surf, flooding, and thunderstorms to the Bay Area. Numerous reports were received of downed trees and power lines. Winds were recorded between 60 and 100 mph. Downed trees resulted in two fatalities.

View location on OpenStreetMap → (37.7977, -122.0259)

Source: NOAA Storm Events Database, event_id 797448. Narrative written by the NWS forecast office that issued the report.