Don’t expect much sun in SF this Labor Day weekend

There won’t be much use for breaking out beach towels and slathering on sunscreen around San Francisco this Labor Day weekend, as the foggy tendrils ensnaring the city aren’t going anywhere anytime soon.

Temperatures are expected to only reach highs in the mid-60s through the holiday weekend, with nighttime lows dipping to the mid-50s, said Suzanne Sims, a meteorologist with the National Weather Service.

What’s causing the mild temperatures to linger?

A low-pressure system this week especially has emboldened a sea breeze to whisk the chilly Pacific air into the ever-present clouds that call San Francisco home.

The last time that happened was almost 75 years ago in 1942, according to Jan Null, a meteorologist for Golden Gate Weather Services who has tracked Bay Area weather for decades.

San Francisco temperatures averaged 65 degrees this August, according to Sims, down three degrees from the historical average of 68 degrees.

What Null calls the “Mediterranean climate” of San Francisco is really just hitting its stride in September, when high-pressure systems move in and help dissipate some of the cloud cover.