An Excessive Heat Warning is in effect through Wednesday night in much of the greater Bay Area because of temperatures that could reach 110 degrees in some inland locations and up to 96 degrees in downtown San Francisco, according to the National Weather Service.
Tuesday saw triple-digit temperatures by the early afternoon in places like Olema Valley in Marin County that had a 104-degree reading and Livermore at 100 degrees as of 1 p.m.
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The hot weather will continue Wednesday and will be accompanied by some offshore winds between 20-30 mph that prompted the weather service to issue a Red Flag Warning for inland parts of Monterey County and other nearby regions from 3 a.m. Wednesday to 8 p.m. Thursday.
The Bay Area Air Quality Management District has also issued a Spare the Air alert for Wednesday, the third straight day of the alerts, because of expected unhealthy levels of smog in the region.
Here's how residents are coping with the autumn scorcher.
San Francisco's hottest day since 2022
San Franciscans found themselves soaking up the sun and trying to beat the heat on the hottest day since Oct. 19, 2022.
In the Mission District where temperatures are generally the hottest in the city, many parents and young kids were cooling off at the Garfield Center Pool. San Francisco Rec and Park announced free swimming at public pools from 11 a.m. to 3 p.m. on Tuesday.
Workers near Salesforce congregated at the Indian-inspired ice cream shop Koolfi Creamery where in anticipation of the hot stretch, owner Priti Narayanan released their summer flavors.
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One customer, Jeremiah Glodoveza, nodded his approval. "It's amazing, the flavors are truly authentic and I haven't tasted anything like this since being in Mumbai," Glodoveza said.
One woman also in line for ice cream, explained why on steamy days like these going to work is not so bad.
"When you don't have AC at home, you might as well come to the office," she laughed.
According to the U.S. Census Bureau American Housing Survey, 92% of households in the country have air conditioning. In California, it is 78%. But in San Francisco, that figure is less than half.
Queueing up for coolness in East Bay
Queueing up for coolness in East Bay
Seniors in Concord queued up to get inside and enjoy the AC on this very hot October Day. Pittsburg and Concord were among the cities that opened up cooling centers for people seeking shade; 71 degrees is after all much better than 100 plus if you don't have AC in your home or office.
Down in Dublin, residents chilled out at 69 degrees inside the library with comfy chairs, computer screens and videos to pass the time.
"I live in a small cottage in Hayward and my fans can only put out so much with no AC. I come out to this side of the hill where it's a little hotter, but I can stay in a hotel where there's a pool and AC accessible and enjoy my days off," said Troy Godinez, Hayward resident.
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Most of the time in the Bay Area, with the fog rolling through the golden gate you can get by without AC. But then there are times you need it.
"I don't have air conditioning in my home and it's nice to have a place to go when these temperatures rise and you don't have any airflow and you need to get cool," said Shari Jackman, Dublin communications manager.
Even though it's October, pumpkin spice lattes didn't take center stage on Tuesday - instead people gravitated to summer staples like ice cream to make it through this heat wave.
Helping the unhoused from the heat in South Bay
Helping the unhoused from the heat in South Bay
In the South Bay, a severe heat wave is putting the homeless population at increased risk. Shaunn Cartwright from the Unhoused Response Group has been distributing essential supplies, such as water, to those in need, highlighting that people were unprepared for the heat, assuming the weather would cool off in the fall.
"They weren't ready for this," Cartwright said. "So it's really hard and so you're not looking at the weather because, you know, you're assuming that it's fall and I don't have to think about this."
Santa Clara County has opened 21 cooling centers to support the unhoused, with outreach teams providing resources like bottled water, tarps, and cooling towels.
Pastor Scott Wagers from CHAM Deliverance Ministry has also been on the front lines, warning the unhoused that the heatwave could last all week and providing them with critical information and supplies.
As officials work to mitigate the heat's impact, most cooling centers in San Jose will remain open through Sunday.
Bay City News contributed to this report.