Excessive Heat — North Bay Mountains, California

2021-07-10 · North Bay Mountains, California

Event narrative

Cazadero CWOP station reported high temperature of 109 degrees F.

Wider weather episode

Strong high pressure building over the region in early to mid July brought warm to hot temperatures across the interior. Daytime highs rose into the 100s with locations across the East Bay up to 110 degrees between July 9th and 11th. Overnight lows remained warm, particularly across higher elevations where temperatures were still in the 70s and 80s in the early mornings. Additionally, prolonged dry conditions resulted in near record dry fuels for July. This along with breezy afternoon winds prompted the Diablo Fire in Contra Costa County.

Source: NOAA Storm Events Database, event_id 966971. Narrative written by the NWS forecast office that issued the report.