Winter storms will bring snow to lower elevations, but won’t be enough to erase years of dry weather made more severe from climate change.
(Bloomberg) — An unusually cold winter storm that’s forecast to bring snow to the hills surrounding San Francisco and Los Angeles this week could make for some picturesque moments but won’t end California’s historic drought.
The storm is expected to kick off several weeks of cooler, wetter weather after a month of mostly dry conditions. The systems won’t bring the sort of deluges seen at the start of the year, when a series of atmospheric rivers drenched California with heavy rain and deep snow, making a dent in the state’s prolonged drought, while triggering mudslides, floods and evacuations and killing at least 20 people.
“I don’t think we’re going to completely step out of drought,” said Brad Rippey, author of the US Drought Monitor that maps conditions across the country. “Some parts of the state will enter the dry season in drought, but it’s going to be reduced from what we currently see.”
A large arctic blast from Canada is expected to dump as much as three feet of snow in California’s Sierra Nevada mountains by Saturday, and up to a foot of powder on the highest peaks near San Francisco. That storm will be followed by a couple of other colder weather systems at the end of February and early March, said Michael Anderson, state climatologist for the California Department of Water Resources. The state’s wet season typically spans November through March.
“We are getting some additional precipitation, which is very helpful,” Anderson said. “February isn’t a complete bust.”
It will take several years of wet winters for the state to replenish its badly overdrawn groundwater supplies, Anderson said. Residents and farms have become overly reliant on the state’s aquifers during the drought, which have supplied up to 60% the drinking water and irrigation supplies in dry years. In non-drought times, aquifers are tapped for about 40% of the state’s total use.
Elsewhere in the US West, the storm will likely provide a small bump for key Colorado River reservoirs, including Lake Mead and Lake Powell, which are at historically low levels, Rippey said. But it probably won’t offer much relief from severe drought conditions in the Central and Southern Plains because most of the moisture will fall further to the north.
Since the start of the year, California has seen improvement in its parched landscape. The state started 2023 with nearly 98% of its land in some stage of drought, according to the US Drought Monitor. That dropped to nearly 85% as of Feb. 14, thanks to nine storms that inundated the state over a three-week span from late December to mid-January. Those atmospheric rivers also helped bring the state’s depleted reservoirs to near-normal levels and to build up its mountain snowpack, which is nearly double the historical average for this time of year.
This week’s storms in California will add to the already impressive snow in the Sierra Nevada — and help it stick around longer once the summer arrives. Last year, the state started January with a healthy Sierra snowpack, only to see it melt in a warm, dry February and March. The state’s snowpack typically supplies about a third of its water needs.
“It’s looking like we’re going to hold onto this snowpack for a pretty long time — fingers crossed,” said Andrew Schwartz, manager of the Central Sierra Snow Lab, which studies California’s mountain snows from a site near Lake Tahoe. The snowpack at the lab today holds about 60% more water than it did a year ago, and the coming storms will add to it.
“It’s safe to say we’ve beat last year’s curse of starting out great and then tapering off,” Schwartz said.
The snow has already proven to be a big boon for the region’s ski resorts. Over the long Presidents’ Day weekend at Mammoth Mountain, skiers enjoyed nearly perfect conditions on the slopes and local restaurants were packed with diners in the evening.
In the Lake Tahoe area, the snowy winter has brought throngs of skiers to the slopes — enough to jam local roads. As irritating as the traffic may be, the snow has been a welcome change for a tourism-dependent region that has endured both dry winters and summer wildfires in recent years. Heidi Hill Drum, chief executive officer of a Tahoe-area economic development nonprofit, said she’s hitting the slopes Thursday for the first time this year.
“My 14-year-old is pretty hard to please, and he came home the other day and said `That was the best snow I’ve ever seen,’” she said.
–With assistance from Brian K Sullivan.
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