When the Bay Area heat wave will peak

The ongoing heat wave that has broken multiple weather records across California is still building in the Bay Area.

A heat advisory for the Bay Area issued by the National Weather Service remains in effect through at least Friday. Karleisa Rogacheski, a meteorologist with the weather service, told SFGATE the temperatures are expected to rise Wednesday and peak on Thursday. 

“We kind of climb on the temperature ladder, so to speak, each day. Tomorrow will be a couple of degrees warmer,” she said. 

The heat wave is the result of a ridge of high pressure that has been strengthening over California and pushed temperatures higher. Multiple temperature records have been broken this week, and more are likely to fall as the hottest weather to date arrives.

Downtown San Francisco is forecast to reach 87 on Thursday, while Oakland is likely to reach 92. In the North Bay, interior valleys will likely reach the low 90s, while areas along the Pacific Coast should be noticeably cooler. In Bodega Bay and along the San Francisco shoreline, the temperatures are forecast to reach the 70s, according to Rogacheski. Parts of the South Bay, including Santa Clara County, could see temperatures reach the low 90s and areas closer to the San Benito County border near triple digits. 

The long-duration heat wave could increase the risk for health complications related to the hot weather, and the weather service warned that people living in certain areas, including near the Santa Cruz Mountains and Carmel Valley, could have “a high level of danger for heat-related illnesses.” 

Rogacheski said temperatures will likely start to cool at the end of the workweek, but it will only be a small shift.

“Friday will be a couple of degrees cooler, so generally a similar temperature pattern, anywhere from about 2 to 5 degrees cooler, depending on the location,” Rogacheski said.

She explained the ridge of high pressure that has been “dominating” the forecast leading to the heat wave will transition “to more zonal flow and high pressure moving off to our east.”

Next week, temperatures are expected to remain slightly elevated but not close to the record-breaking hot weather that arrived this week. But one thing that is sticking around is dry weather. 

Rogacheski said there is still no sign of any rainfall in the upcoming forecast.