San Jose, California – Temperatures dropping to 24 degrees in the eastern Santa Clara Mountains are triggering an Extreme Cold Warning overnight, with freezing conditions impacting communities near US-101, Interstate 280 and Highway 17 through 9 a.m. Wednesday.
According to the National Weather Service in San Francisco Bay Area/Monterey, the Extreme Cold Warning covers the eastern Santa Clara Mountains, the Santa Lucia Range and interior mountains of Monterey and San Benito counties. A Cold Weather Advisory is also in effect for the Santa Clara Valley, Santa Cruz Mountains and North Bay Interior Valleys, where temperatures may fall as low as 34 degrees. All alerts remain active from midnight through 9 a.m. Wednesday.
Communities near San Jose, Morgan Hill, Gilroy and Hollister could wake up to widespread frost, especially in sheltered valleys along US-101 and Highway 152. In the Santa Cruz Mountains, cold air pooling near CA-17 and Highway 9 may create icy patches on elevated bridges before sunrise. Monterey County interior routes near Highway 68 and Highway 101 could also see freezing temperatures.
Officials warn that prolonged exposure to these temperatures can lead to hypothermia, particularly for unhoused individuals. Pets, livestock and sensitive crops are also at risk. Residents should cover plants, bring pets indoors and check on vulnerable neighbors.
Conditions will gradually improve after 9 a.m. Wednesday as sunshine returns, but additional cold mornings remain possible later this week.
