The calmest month for winds at San Francisco International Airport is generally January, but as reported by the San Francisco Chronicle, low wind speeds can bring air that is unhealthy to breathe.
What’s happening?
According to the Bay Area Air District, a Spare the Air alert was extended through Saturday as pollution built up and has lingered over the area. The air quality dropped into the “moderate” or “unhealthy for sensitive groups” categories in cities such as San Francisco, Oakland, Redwood City, and San Jose. Some sensors even showed “unhealthy for all” readings near the bay and delta areas.
The air quality was impacted by pollutants from wood burning, vehicles, and industrial sources that became trapped lower in the atmosphere because of the calm winds.
“A high-pressure system is deflecting precipitation and clouds away from California. Beneath it, skies are clear and cloudless, but the air is stagnant,” Anthony Edwards, a newsroom meteorologist, wrote in the Chronicle report…