Several triple-digit heat waves have cooked the Bay Area this summer. Before summer ends, another one is on the way, with a heat advisory from the National Weather Service (NWS) extending through 7 p.m. today and warning of triple-digit temperatures in the East Bay.
NWS writes: “Strong high pressure over California will result in very warm to hot temperatures again today, with temperatures forecast to be anywhere from 10 to 18 degrees above average. These temperatures will result in heat impacts to those sensitive to heat and potentially those who overexert or overexpose themselves to the daytime heat. [...] Heat related illnesses such as heat exhaustion and heat stroke will be possible. People most vulnerable include those who are spending considerable time outdoors.”
The forecast includes estimated temperatures ranging from 96 in San Francisco, 100 in parts of the North Bay, 103 in the East Bay valleys, and 104 in the Santa Clara valley.
Naturally, “the highest temperatures will occur during early to mid afternoon,” with “a light onshore breeze” easing conditions in the evening.
At the same time, the Environmental Protection Agency’s AIRNow site, which measures air quality for unhealthy factors like ozone and particle matter, forecasts conditions much worse than usual across the East Bay and South Bay, with conditions deemed “unhealthy for sensitive groups” predicted.
Heatwaves often engender rushes of bad air. Writing in 2018, Thought.Co explained, “The heat and sunlight essentially cook the air along with all the chemical compounds lingering within it. This chemical soup combines with the nitrogen oxide emissions present in the air, creating a “‘smog”’of ground-level ozone gas.”
Although the heat is primarily a discomfort for most people, heat-related deaths do happen in the Bay Area.
KQED reports that “even in cool, coastal California, extreme heat sickens and kills people. In 2017, extreme heat killed 14 people in the Bay Area,” and that even relatively temperate hot days—85 degrees in SF—can be deceptively harmful.
In response to the forecast, SF Recreation and Parks says it will waive admission fees to seven swimming pools in the city on Friday: Balboa Pool, Coffman Pool, Hamilton Pool, MLK Pool, Mission Pool, North Beach Pool, and Sava Pool.