In case you are somehow oblivious to air temperature: it's hot today. Like sweaty keyboard hot. And while there's a gentle breeze keeping things from becoming simply unbearable (read: 83 degrees), that breeze may turn into a stagnant, lung-clogging, smog-filled stillness come tomorrow. So, to preserve your tender bronchioles and alveoli, the Bay Area Air Quality Management District has declared Saturday, September 7th an official Spare the Air day.
We've already cracked the 80-degree threshold for Friday and forecasted temperatures, which are never really reliable in the city anyway, are expected to hit the upper 70s tomorrow as well. Those warm temperatures, combined with low winds mean vehicle exhaust will be especially suffocating over the weekend. Or maybe we'll just end up with a nice warm Saturday night.
Anyhow, the BAAQMD recommends you avoid trying to get around (or out of) the city via internal combustion engine and instead opt for public transit, a bicycle or your own two feet. (Caution: these modes of transit have been known to produce an undesirable byproduct known as "sweat.")
That said, now would be as good a time as any to give Bay Area Bike Share a spin.