San Francisco cooks under "heat dome" for first day of October

San Francisco started off October on a hot note, with parts of the city registering temperatures as high as 95 degrees on an unusually warm start to the first full month of autumn .

According to CBS News Bay Area meteorologist Zoe Mintz, Tuesday marked the first day San Francisco had broken the 90 degree mark since 2022. She said 95 degrees was also the hottest temperature to be measured in the city since 2020.

People in the city aren't used to that kind of heat, especially since the majority of the older buildings don't have air conditioning. In fact, Tuesday was one of those rare days where San Francisco's city government website was providing a list of public libraries that residents can use as cooling centers .

KPIX First Alert Weather: Current conditions, alerts, maps for your area

"Would you like to buy some water?" Gedioni Bolio asked a group of tourists walking near Union Square. He saw Tuesday's heatwave as a business opportunity.

A freshman at SF City College, Bolio loaded up an ice chest with cold drinks and headed out to the hottest spots in the city.

"I was just laying in bed. It was hot, and I just wanted to go out. I had nothing better to do. No school today," said Bolio.

Across town in the Mission, a woman named Marilyn was the first customer in the door at Mitchell's Ice Cream . She was there waiting for the shop to open at 11 a.m.

"It's so hot, we're getting Halo Halo," she says. It's her favorite ice cream float.

The ice cream shop expected it would only get busier as the day goes on, so that means a larger than normal ice cream delivery.

"Extra because it's hot, exactly," explained David, the delivery driver. He has to be bundled up because he's in and out of the freezers all day.

"It's hot on the street, but it's cool inside," he said of the refrigerated truck.

Many of the city's pools are offering free admission Tuesday , like Mission Pool.

"This is one of our busiest times. Our lap swim 11 a.m. to 1 p.m. is always popular so I expect it's going to be more popular," said Mission Pool lifeguard Gwen Dornan.

While Tuesday was forecast to be the hottest day in San Francisco this week, Wednesday's temperatures are expected to be above normal as well .