Strong Wind — East Bay Interior Valleys, California

2021-01-19 · East Bay Interior Valleys, California

Event narrative

Tree down blocking roadway at Wildcat Canyon Rd and San Pablo Dam Rd.

Wider weather episode

A rare winter time offshore wind event affected the Greater Bay Area in mid to late January. It was unusual given the long duration and wide areal coverage as well as the time of year. An upper level disturbance passed over the region the 17th-18th leading to a tightening offshore pressure gradient before a second and stronger disturbance the 18th-19th tightened it further. This lead to two bursts of strong offshore winds. Higher elevations across the region reported gusts between 60 and 80 mph with two sites reaching 90. Lower elevations also were notably in excess of 40 mph. These winds resulted in tree damage, downed trees, and downed powerlines causing power outages. This all led to a rare January Red Flag Warning for Monterey and San Benito counties where fuels remained dry from lack of rainfall. Roughly a dozen small fires broke out in the Santa Cruz Mountains, with two becoming relatively large for January. Full storm summary https://www.weather.gov/mtr/Wind_1_17-19_2021.

Source: NOAA Storm Events Database, event_id 931884. Narrative written by the NWS forecast office that issued the report.