By late morning on Monday, temperatures around the Bay Area are forecast to rise rapidly and a heat advisory will be in effect for the entire region.
"A fall heat wave kicks off today and will last for several days," the National Weather Service said in a statement issued Monday.
The heat advisory goes into effect at 11 a.m. and lasts through Wednesday night, but it could be extended for some parts of the Bay Area.
Interior temperatures are expected to reach the low- to mid-100, and coastal areas will be in the 80s to mid 90s.
"With offshore winds fighting the marine layer, the coast will also feel the heat today," the weather service said.
A sea breeze is expected to bring some late afternoon cooling relief to the coast.
The heat wave will likely bring red flag warnings, as offshore winds are expected to continue Tuesday night into Wednesday morning.
Local
"This period will bring the peak of fire weather concerns, especially at higher elevations," the weather service said.
People and pets should not be left in cars without air conditioning, and outdoor activities should be limited for those who are sensitive to heat, and people should stay hydrated.
Get a weekly recap of the latest San Francisco Bay Area housing news. Sign up for NBC Bay Area’s Housing Deconstructed newsletter.