Bay Area weather: Heat advisory issued for much of region

The heat returns Tuesday to much of the Bay Area, with daytime highs in the 90s in several places and approaching triple digits in some inland areas.

A heat advisory has been issued from 11 a.m. through 8 p.m. Tuesday for Santa Clara Valley, the eastern Santa Clara hills and the interior valleys of the East Bay and North Bay. The hills of interior Monterey County also fall under the advisory.

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The hot weather has fire crews on high alert. Cal Fire is bringing staffing to peak levels and putting more air and ground equipment on standby to be prepared for the next brush fire.

With temperatures expected in 90s and near 100 in most inland areas, a heat advisory is in effect for much of the day. Vianey Arana has the Microclimate Forecast.

"It’s based on whatever incidents that we’re having; we’ve seen quite an increase in fire activity recently," Cal Fire spokesperson Chelsea Burkett said. "But it’s also based on weather forecasts and what we’re looking at going forward."

Coastal temperatures are expected to remain cool, topping out in the 60s and 70s.

Tuesday is expected to be the hottest day of the week, but temperatures are expected to stay above normal until Thursday, when a cool-down is expected to start, the weather service says.