Dense Fog — Northern Sacramento Valley, California

2018-03-21 · Northern Sacramento Valley, California

Event narrative

There were 5 vehicles involved in an accident attributed to dense fog. There were 7 injuries reported.

Wider weather episode

Torrential rain from an atmospheric river with locally heavy convective showers brought flash flooding to portions of the northern Sierra and Motherlode foothills. The heaviest flooding was in Groveland, where 4-5 of rain fell, combining with 8-9 of rain in higher elevations upstream. There was also widespread damage in Tuolumne County to roads from debris flows, soil erosion, erosion of water conveyance systems, sewer systems that were inundated with excess water and debris. Roads damaged inluded state Highways 49 and 132. Moccasin Dam was damaged and came close to failure, with road closures. A tornado struck an amphitheater in Wheatland and caused minor damage. Heavy snow caused travel problems over Sierra highways.

Source: NOAA Storm Events Database, event_id 747048. Narrative written by the NWS forecast office that issued the report.