After nearly a year without rain, a series of potent Pacific storms are directed at Northern California this week, potentially bringing as much as a foot of rainfall and up to three feet of snow in the Sierra Nevada.
A wetter than average forecast for late October could dampen wildfires burning in Northern California and help ease drought conditions, according to the National Weather Service.
The latest weather outlook for the latter part of this month calls for above-normal precipitation in California, with possible high-elevation heavy snow in the Sierra Nevada and the Cascades. There is also potential for an atmospheric river between Oct. 21 to Oct. 27, forecasters said.
The current ongoing two-year dry period in California, punctuated by the third-driest water year on record for the Central Sierra, is part of California’s overall arid fate so far in the 21st century, according to the state Department of Water Resources.
The Golden State’s hydrology now increasingly resembles conditions in the Colorado River Basin this century, where multiple, consecutive, drier-than-average years are mixed with an occasional wet year. California’s last wet water year was 2016-2017, the second-wettest on record.
California water regulators took unprecedented action this week, passing an emergency regulation that will bar thousands of Californians from diverting stream and river water as the drought worsens.
The State Water Resources Control Board voted unanimously Tuesday to pass the “emergency curtailment” order for the Sacramento-San Joaquin Delta watershed. The watershed encompasses a wide swath of the state, from the Oregon border in northeastern California down into the Central Valley.
In Santa Clara County, lawns are dry, a reservoir is nearly empty, and water restrictions are mandated. After two winters with very little rain — and San Jose’s driest year in 128 years of record keeping — the county is marked by one of the worst droughts in modern history.
Santa Clara County’s experience of drought is set apart from the rest of the state by a myriad of issues — less water from the Sierra Nevada, the effect of human-caused climate change on water supplies, and a case of incredibly bad luck.
Droughts are common in California, but this year’s is much hotter and drier than others, evaporating water more quickly from the reservoirs and the sparse Sierra Nevada snowpack that feeds them.
The state’s more than 1,500 reservoirs are 50% lower than they should be this time of year, according to Jay Lund, co-director of the Center for Watershed Sciences at UC Davis.
California’s rain year officially ended Wednesday, and the data reflects what the dry landscape in much of the Bay Area already shows: It wasn’t pretty. Data shows that for many of the major regions of California, the July 2020-June 2021 rain year was one of the top 10 driest ever. Even more troubling is that the extreme dry spells are starting to stack up, especially in the Sierra Nevada watersheds that supply so much of the state’s water.
California’s severe drought was made worse this year by a shocking surprise.
Every year, much of the drinking water that flows through the taps of millions of Californians begins in the Sierra Nevada. Snow and rain fall on the vast mountain range during the winter months, and the water moves downhill into streams, rivers and reservoirs in the spring and summer.
But this year, in a trend that startled water managers, much of that runoff simply vanished.
Earlier this month, camera crews once again gathered in the Sierra Nevada to watch a man plunge a pole through the snow. The pole was removed and, following a tense few moments, Californians learned we experienced another dry winter, and we are plunging further into drought. These snowpack surveys are quaint rituals, but they’re also a jarring reminder of how little technological innovation has occurred in California’s water sector. The case for action is clear.
Another March storm moved through California on Monday, bringing snow to the Sierra Nevada, rain showers elsewhere and gale conditions offshore.
A mix of winter storm warnings and winter weather advisories stretched the length of the Sierra and southward into mountain ranges of Southern California that were just coated with snow last week.
Caltrans recommended motorists traveling through the Sierra check for chain requirements.
The Water News Network is San Diego County’s source for water news and information.
