SAN FRANCISCO (KRON) – It’s going to be hot this week, with temperatures forecasted to hit the 90s across the Bay Area. KRON4 looked into the hottest days we’ve seen on record in our area. 

Using data from the National Weather Service, we determined that the hottest day in San Francisco’s history occurred on September 1, 2017 when the city hit a blistering 106 degrees. We know that areas outside of the city can be even hotter on days like this, and that was true in 2017 too. San Jose hit a high of 108 on Sept. 1, 2017. 

There was certainly a heat wave that week, because on Sept. 3, 2017 the Napa area hit 108 degrees, nearly 20 degrees hotter than their historical average. But who had it the hottest? Our friends in Gilroy saw their thermostats hit 112 degrees on Sept. 2, 2017. 

Hottest days on record across the Bay Area

Gilroy – 115 degrees on July 15, 1972

San Francisco – 106 degrees on September 1, 2017

Big Sur – 106 degrees on September 2, 2017

Hollister – 112 degrees on July 22, 2006

Kentfield – 112 degrees in Jul 7, 1913

King City – 115 degrees on September 2, 2017

Livermore – 113 degrees on July 23, 2006

Monterey – 104 degrees on October 08, 1996

Napa – 113 degrees in June 14, 1961

Salinas – 107 degrees on September 2, 2017

San Jose – 108 degrees on September 1, 2017

Santa Cruz – 110 degrees on September 3, 2017

Sonoma/Santa Rosa – 111 degrees on September 6 & 7, 2020

San Rafael – 110 degrees on September 1, 2017


The CDC recommends that you take precautions any time you are exposed to extreme temperatures. Staying hydrated and using sunscreen are both recommended when spending time in high temperatures like these.