Excessive heat warning continues through Friday across Bay Area

NAPA, Calif. - An excessive heat warning will remain in place in the Bay Area through late Friday evening as hot temperatures continue to scorch the region.

Inland temperatures could reach as high as 108 degrees on Thursday with coastal highs up to 95, the National Weather Service said. 

San Francisco, which has seen unusually hot temperatures in recent days, could reach up to 87 degrees on Thursday, according to the NWS.

Much of the North Bay, East Bay and South Bay are under the NWS' excessive heat warning, while San Francisco is under a heat advisory. 

San Francisco hit 94 degrees on Thursday, a temperature that's only been reached 15 times in the last 150 years, the National Weather Service said.

North Bay

In Napa, residents will see temperatures in the 90s on Thursday. Besides the obvious impact of hot weather, increasing temperatures can also affect the grape harvest. 

"This heat wave has certainly accelerated the tail end of harvest to where, earlier on, we had some cooler temperatures and everything was going kind of slow and controlled in a great pace. It's accelerated a little bit," said Caleb Mosely, executive director of Napa Valley Grape Growers. "So we're certainly seeing this is one of the busier weeks of harvest thus far."

He says resiliency is key for grapes during hot weather. 

"We plant the vineyard to create a resilient, resilient system for this particular type of heat event. So the cool nights help out exceptionally because they allow the vines to kind of recover the turgidity of the berry," he said.

East Bay

Farmworkers in East Contra Costa County, including Filiberto Ruiz, have continued to harvest crops in fields despite the scorching weather. Ruiz, who has worked in agriculture for over 20 years, said he's used to working in such conditions.

"We are used to this kind of weather. We do this every day. I make sure to drink lots of water and keep my body and head covered," Ruiz said in Spanish.

Nonprofit organizations like Hijas del Campo (Daughters of the Field) are stepping in to help outdoor laborers by providing hydration packs, access to mobile health clinics, and monitoring conditions in collaboration with Contra Costa health officials.

"Many times, people don't realize they're experiencing heat-related issues," said Marviel Mendoza of Hijas de Campo. "Farmworkers are often paid by the hour or by the bucket, so they’re used to pushing through to finish as much as they can."

California law requires employers in outdoor workplaces, including agriculture, construction, and landscaping, to provide shade and water for their workers. However, the ongoing heatwave has led to reduced work opportunities for some.

Jose Llosslla Diaz, a worker at the Monument Impact Day Labor Center in Concord, said extreme weather makes finding work more difficult.

"We have less work when it’s hot, just like during the rainy season," Diaz said. "Companies want to avoid accidents; they don't want workers fainting or getting sick from the heat."

The excessive heat warning issued by the National Weather Service was originally set to expire last night, but will continue through Friday