Frost/Freeze — North Bay Interior Valleys, California

2021-02-23 to 2021-02-25 · North Bay Interior Valleys, California

Event narrative

Four consecutive mornings of below-freezing temperatures forced some Sonoma County wine grape growers to protect swelling buds following prior weeks of warm, dry weather. The temperature dropped to 26F in downtown Santa Rosa on the morning of the 24th, a new daily record.

https://www.pressdemocrat.com/article/news/freezing-temps-prompt-sonoma-county-winegrowers-to-protect-early-buds/.

Wider weather episode

A cold airmass aloft in conjunction with clear skies and light winds allowed temperatures to drop down into the 20s and low 30s away from the coast for 3 consecutive mornings from Feb 23- Feb 25. Freeze warnings were in effect these mornings for interior valleys and mountains from North Bay through the Central Coast. A frost advisory was issued for the SF Peninsula, Bay Shoreline, and coastal Monterey Bay.

Source: NOAA Storm Events Database, event_id 1012111. Narrative written by the NWS forecast office that issued the report.