Two more weeks of rain and snow projected in the Bay Area and Sierras

The Bay Area and the rest of Northern and Central California are in for two weeks of wet weather and snow, according to Drew Tuma, a meteorologist for ABC 7.

“It looks like Sunday, New Year’s Day, could be the only totally dry day we have in the next 14 days,” Tuma told The Standard this morning after tweeting a similar message to his followers.

The stormy pattern runs counter to what many meteorologists would have expected. Although the Bay Area has been quite wet over the past few days, the region is in the midst of what weather scientists refer to as a “La Niña” year—which normally coincides with clear skies and parched earth.

During a typical La Niña weather pattern, a strong high-pressure system—sometimes called a “Ridiculously Resilient Ridge”—camps out over the Gulf of Alaska, channeling rain away into the Pacific Northwest and the northernmost tip of California.

However, there is currently a pocket of high pressure situated over Hawaii while the low-pressure system is occupying the air above Alaska, resulting in “a parade of storms into California,” Tuma said.

That’s welcome news to skiers and snowboarders, who can expect the Sierra Nevada to receive several feet of snow in the coming weeks.

But if you’re planning a trip to the slopes, you might want to wait until the first weekend of January. Tuma said he anticipates the warmer storm front coming this weekend—Dec. 30-Jan. 1—will bring mostly rain to lower elevations in the Lake Tahoe region and only deposit a few inches of wet snow at local resorts. Next weekend, however—Jan. 6-8—could dump 3 to 5 feet of powder, especially at higher elevations.

The rainy weather is also good news for California’s urban water managers, who have been struggling to meet demand. However, even a wet December and early January may not be enough to refill reservoirs and offset the West Coast’s ongoing megadrought. 

Unfortunately for some in the Bay Area, including San Franciscans living in flood-prone neighborhoods, another two weeks of stormy skies may spell trouble on the ground.

The city’s sewer system is unique and unusual in that it collects both stormwater and wastewater in a single set of pipes. KQED recently reported that about 10 times a year, heavy rains overwhelm San Francisco’s sewers, forcing sewage and stormwater into nearby waters—and sometimes into the streets—due to bottlenecks in the system.

According to the San Francisco Public Utilities Commission, the city’s sewer system handles roughly 80 million gallons of wastewater daily, but when it rains, city facilities can collect and treat up to 500 million gallons of water a day.
A recent report by WalletHub concluded that San Francisco has the highest rate of homes with inadequate plumbing in the country. In recent years, municipal sewage problems have gotten so severe in some San Francisco neighborhoods that residents have banded together in an effort called Solutions Not Sandbags to call out the city’s sewage problems and demand action.