While disruptive, the storm has helped replenish a depleted snowpack after an exceptionally dry winter. The water stored in the snowpack is critical for the region’s water supply and for moistening vegetation before fire season.

“We got anywhere between 2 to 4 feet at Lake [Tahoe level],” said Jim Wallmann, a meteorologist at the National Weather Service in Reno, Nev. “Above 7,000 feet, it was 3 to 6 feet.”

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Normally, such snowfall would also be a boon for ski areas but most, if not all, are shuttered in the midst of the coronavirus outbreak. Wallmann said that’s even affecting the data the National Weather Service has to work with.

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“It’s kind of tough [to get snowfall reports] with so many of the ski resorts shutting down,” he explained.

Snow fell at breakneck pace during the weekend, when snowfall rates at times eclipsed two inches per hour. Some places have the equivalent of between 10 and 20 inches of liquid water stored in their snowpacks.

In the meantime, the flakes continue to fly into Wednesday — and more snow is in the offing thereafter. In fact, several feet more is possible next week if another fire hose of Pacific moisture targets the Golden State.

The snow began in most spots Saturday, lasting through Monday as intermittent heavier rounds rotated into the region. Part of the culprit is an upper-level low-pressure system.

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That chilly swirl of cold helped drag a strip of moisture-loaded air off the Pacific. The juicy air helped deposit exceptional snow in the higher elevations.

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“For us, it’s actually what we know it to be, a cold heavy snow pattern, where we often see heavy totals in the lee-side valleys even into Reno,” Wallmann explained.

Heightened avalanche danger

Everything that’s fallen has contributed to a snow pack more than 100 inches deep in some locales. That’s raised fears of an unstable snowpack.

On Sunday, the Sierra Avalanche Center issued an avalanche warning of high avalanche danger. According to the National Weather Service, that indicates “very dangerous avalanche conditions,” with “travel in avalanche terrain not recommended.”

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“Feet of new snow and shifting winds created dangerous avalanche conditions in the backcountry at all elevations,” wrote the center. “Human-triggered avalanches involving large slabs of drifted snow in wind-exposed areas and slabs of new snow in sheltered areas are likely [Tuesday.]”

Traffic impacts

California Highway Patrol closed sections of Interstate 80 near Truckee on Saturday after a series of spin-outs blocked traffic in heavily-falling snow.

Meanwhile, winds gusted to 115 mph at Alpine Summit, and 113 mph in Squaw Valley. Strong winds even in the lowlands toppled a tractor-trailer in Washoe Valley, Nev.

Precipitation in California is beneficial, but much more needed

The recently accumulated snowpack is good news for many in California, a state which has largely lagged behind in accumulated precipitation during the 2019 to 2020 rainfall season. Since July, most locations have been a third of the way below average for the date.

The addition of new moisture to the snowpack will more than help take a dent out of that deficit and replenish the availability of spring meltwater in inland areas. But it’s going to take an awful lot to have a meaningful impact.

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“Well, basically, you used the word I was hoping you’d use, and that’s a ‘dent,’ ” said Kevin Durfee, a hydrologist and meteorologist at the National Weather Service in Hanford, Calif. “We’re way behind in Sierra snowpack right now."

Signs point to a continued waterlogged pattern for much of California, with an active jet stream slamming more sprawling storms into the state. The next big mountain snowmaker should arrive late this weekend into early next week. But will it be enough?

“The storm we’ve had is certainly beneficial,” Durfee said, “and our pattern looks to be active for the next 7 to 10 days with more opportunities for accumulating snow, but … we’ve got a long way to go.”

Durfee said the southern Sierra Nevada’s snowpack is a bit more than a third what it normally should be, with the central and southern Sierra still not even halfway to their average snowpack. That could be bad news for fire season, the limited moisture reserves making it easier for parts of the state to dry out faster come summer.

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“The reservoirs right now are holding a good amount of water in them,” Durfee said. “Dam owners are anticipating a drier than normal finish to the year. They can always start releasing more water if they need to. But right now we’re looking at a situation that so far is well below normal. It’s not just going to be one or two storms that’s going to bring us back right where we need to be.”

Durfee said that officials will have a better idea of where the snowpack stands around April 1, when a team of surveyors will head out to inspect the snowpack and report back actual numbers.

But until then, Durfee isn’t overly optimistic.