It’s not your imagination: Weekends have been rainy

The weather forecast calls for rain in San Francisco this weekend — yet again.

Though it hasn’t rained every weekend in the city this year, 2024 has tallied an unusually high number of wet Saturdays and Sundays, with rainy days on nine of the first 14 weekends.

Additional rain this weekend is expected to continue that trend.

“Keep a rain jacket handy if you’re out and about in the Bay Area this weekend, especially Saturday,” said Chronicle meteorologist Anthony Edwards.

Over the first 14 weeks of the year, San Francisco encountered 44 days with rain, including 15 over weekends.

One of the biggest storms this winter came on Sunday, Feb. 4: A bomb cyclone produced intense wind gusts and torrential downpours that caused flooding across the state. Downtown San Francisco recorded about 1.7 inches of rain that weekend.

The city averages around 33 rainy days between January and March, based on data from 1991 to 2020. The unusually wet weather this year concurs with strong El Niño conditions in the Pacific in recent months: El Niño winters are often associated with wetter than average conditions in Central and Southern California.

Despite recurring weekend rain, there isn’t a mysterious meteorological mechanism putting a damper on Saturday and Sunday plans.

“It’s 100% random,” said Jan Null, a meteorologist with Golden Gate Weather Services and adjunct professor at San Jose State University.

It’s been a similar picture across the Bay Area: Santa Rosa and San Jose also faced rain on more than half of the past 14 weekends.

There may be a psychological explanation why it feels like it has rained every weekend: “I think it’s more impactful for most people to have it rain on a weekend,” Null said. “It disrupts plans.”

Still, over the past 35 years, there have been a handful of times that San Francisco recorded more frequent weekend rain over the first three months of the year.

The chart below shows how often it rained on Saturday or Sunday from 1990 to 2024. The rainiest stretch of weekends was in 1998, coinciding with a strong El Niño and one of California’s wettest years on record.

Fortunately for Bay Area residents tired of wet weekend weather, there’s good news looking ahead.

“The long-range forecast looks dry and warm,” Edwards said. “So hopefully next weekend marks the beginning of a sunny weekend trend.”