Air quality officials took the unusual step of declaring a three-day Spare the Air Alert due to sizzling temperatures expected around the region this weekend.
The high temperatures, along with light winds and exhaust from motor vehicles are expected to cause unhealthy ozone, or smog, levels in the Bay Area, according to the Bay Area Air Quality Management District.
The alerts for Friday through Sunday are the fifth, sixth and seventh Spare the Air Alerts for smog in 2019.
A persistent high-pressure system over the Pacific Southwest is driving temperatures higher, delaying ocean breezes and causing unhealthy air quality throughout the region, said air district officials.
"The weather pattern this week continues to persist causing elevated levels of smog, so we are taking the unusual step of calling a 3-day Spare the Air alert through the weekend", said Jack Broadbent, executive officer of the Air District. "We know that when we have high summer temperatures, we experience unhealthy air quality due to pollution from cars and trucks so it is important to reconsider our commuting options so we can reduce traffic and air pollution.
Air district officials warn that ozone can cause throat irritation, congestion, chest pain, trigger asthma, inflame the lining of the lungs and worsen bronchitis and emphysema.
Long-term exposure to ozone can reduce lung function. Ozone pollution is particularly harmful for young children, seniors and those with respiratory and heart conditions. When a Spare the Air Alert is issued, outdoor exercise should be done only in the early morning hours when ozone concentrations are lower.
For more information about the Air District's efforts to address climate change in the nine-county Bay Area is available online.
Residents can register for email AirAlerts at Spare the Air's website.
call 1(800) HELP-AIR, download the Spare the Air App or connect with Spare the Air on Facebook or Twitter.