SAN FRANCISCO (KGO) -- Unhealthy air quality is bad once again and it's shutting down outdoor weekend plans for so many of us across the Bay Area. There was no escaping the bad air on Saturday.
We caught up with Jaime Heilpern after he ran eight miles along the San Francisco waterfront, on a day when the air was smoky and unhealthy.
"I gotta keep the fitness up and using the tools I have, so far so good with this mask," Heilpern said.
Experts say smoke from wildfires is giving the West Coast the worst air quality in the world this week.
Bad air quality prompted Alcatraz to cancel tours of the rock.
"Alcatraz is one of the main spots we had planned, I'm disappointed but it is what it is, we can feel the air is not healthy," said Rupa Phanbanani visiting from Houston.
Alcatraz tour employees were rebooking guests for next week.
San Francisco was invisible above Crissy Field and the Bay Bridge appeared to vanish in the smoky haze.
San Francisco Public Library branches were reopening this weekend as clean air respite centers.
The Main library, Chinatown and Mission Bay branches are offering a room to chill out with some social distancing. A Covid-19 health screening is required before entering.
The Oakland Zoo tweeted it was closed Saturday in the name of health and safety due to ongoing air quality concerns.
In the North Bay, the air wasn't much better. Mt. Tam was shrouded in smoke. McInnis Park in San Rafael was closed because of poor air quality.
Stanford University Pulmonologist Dr. Karen Hardy urges everyone to stay inside this weekend.
"It's dangerous to be out in this bad air, It's important to have a mask and if you have to be outside, wear one with a filter like N95 mask," said Doctor Hardy.
Some possible good news, cleaner air could make a comeback next week.
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