From weather.com, as per excite.com

Frost Advisory – Urgent – weather message has been issued for Santa Clara county CA valid from Sun Feb 09 2003 03:46 PM PST until Sun Feb 09 2003 09:00 PM PST .
Napa county-santa Clara county-alameda and Contra Costa counties- Salinas valley/interior Monterey county/san benito county- Sonoma and Marin counties- 343 PM PST Sun Feb 9 2003 …A frost advisory tonight for the inland valleys of the san Francisco and Monterey bay areas… Clear skies and calm winds will Result in temperatures lowering to near or just below freezing for a Short duration by dawn Monday morning. A frost advisory has therefore been issued for the valleys of the North and East bay as well as the Santa Clara and Salinas valleys. Those with tender vegetation should cover or protect it from the cold. Also…Potted plants normally left outdoors should be covered or brought inside away from the cold. Residents in the advisory area should take precautions to protect outdoor pets.