On Tuesday it was boiling at the 170-year-old Alpine Inn, hitting a record breaking 105 degrees. The proprietors of the 170-year-old restaurant, which includes a 250-seat beer garden, made the call Tuesday afternoon to shut down for the rest of the day. The decision cost the restaurant an estimated $25,000 in potential sales.

Alpine Inn in Portola Valley, which reopened Wednesday, Sept. 7, at 11:30 a.m., closed around 2:30 p.m. the previous day, according to Greg St. Claire, one of the restaurant's owners.

"Given the historic nature of the tavern, no AC, the intense heat it was just not safe for my team to work in conditions like this," he said in a Tuesday email. "We will be back open tomorrow."

Wednesday's forecast calls for a toasty high of 93 degrees, but that's lower than Tuesday's highs, which set records in six Bay Area cities. Alpine Inn managers are instructing staff to stay hydrated with fluid and electrolytes, and to communicate if they are not feeling well or overly fatigued, said executive chef and general manager Sean Agoliati.

"We have also adjusted staff schedules to limit exposure to heat during peak heat hours," he said.

During a heat wave in June, which sparked the Edgewood Fire, the historic Filoli estate in Woodside shut down when it lost power along with other nearby Woodside residents.

State officials warned there could be rolling blackouts, but the Midpeninsula has mostly been spared. Palo Alto is the exception. It has seen three power outages so far this week.

Roberts Market in Portola Valley had a brownout last week for an hour or so, but power has stayed on, said Roberts Market Portola Valley's store manager Mike Kerr, who called the heat wave "pretty nasty."

The California Independent System Operator, which manages electricity over the state's high-voltage transmission lines, narrowly avoided having to institute the rolling blackouts Tuesday when the state saw an all-time record power grid peak demand of 52,061 megawatts, according to Bay City News Service. Still, about 57,000 customers lost power at the peak around 9 p.m., PG&E spokesperson Deanna Contreras told BCN.

With temperatures around the Bay Area and elsewhere in the state forecasted to reach triple digits again Wednesday — though slightly lower than Tuesday's highs— the state grid operator has issued another statewide Flex Alert to call for voluntary electricity conservation particularly during the hours of 4 to 9 p.m.

The grid operator encourages people to set their home or business thermostats to 78 degrees or higher during that time, as well as to avoid the use of major appliances and to turn off any unnecessary lights.