Update, Oct. 2, 2:04 p.m The Bay Area Air Quality Management District has posted an air quality alert due to unhealthy air through Tuesday.

Update, 6:43 p.m. The air quality in Berkeley has moved into the “unhealthy range.”

Original story: A red flag warning has been issued for the Berkeley Hills from Thursday, Oct. 1, until Saturday at 6 a.m. due to extreme fire risk as smoke from the Glass Fire in Napa County continues to impact Bay Area air quality.

There have been at least five red flag warnings for the Berkeley Hills in the last three months, with hot, dry summer conditions aggravated by lighting strikes and record-setting heatwaves. The most recent one was in effect last week.

The Bay Area Air Quality Management District (BAAQMD) has also issued a Spare the Air alert from Thursday to Tuesday, Oct. 6, due to smoke from the 55,000-acre Glass Fire burning in Napa County. The fire began Sunday and is only 5% contained, burning simultaneously with the LNU Lightning Complex in the North Bay, which is now nearly contained.

Though the Bay Area experienced a period of clean air after the previous, record-setting 30-day Spare the Air alert, it’s now heading into a total of 44 alert days for the year. That’s approaching the record high in 2017 of 46 days.

Aaron Richardson, spokesman for BAAQMD, said he won’t be surprised if that record gets broken this year.

Air quality is currently in the orange “unhealthy for sensitive groups” range, according to BAAQMD’s monitor at Aquatic Park in West Berkeley, and is expected to remain at that level through Tuesday.

Richardson said air quality will also be impacted by ozone pollution this weekend, in addition to fine particulate matter from the smoke. Though smoke and marine fog mixing can sometimes be called “smog,” the smog that creates ozone pollution typically comes from automobile exhaust and requires hot weather to form.

Wildfire smoke also tends to increase smog formation, according to Richardson.

The Bay Area is currently in the middle of its “fire season,” which experts are increasingly considering a year-round phenomenon due to climate change. Richardson said dry vegetation, hot temperatures and high winds are some of the consequences.

“It’s just pretty obvious that [these] extended wildfire episodes that we’ve had in the last four years or so, is the result of climate change-induced factors,” Richardson said. “It’s been much more dramatic than we had seen in the last 20-30 years.”

Supriya Yelimeli is a housing and homelessness reporter for Berkeleyside and joined the staff in May 2020 after contributing reporting since 2018 as a freelance writer. Yelimeli grew up in Fremont and...