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A massive winter storm is hitting the Sierra. Here's how much snow is expected.

Snow pounds the Sierra Nevada as latest storm soaks the Bay Area
Snow pounds the Sierra Nevada as latest storm soaks the Bay Area 04:51

A Pacific storm packing the heaviest snow of the winter arrived in the Sierra Thursday and is projected to dump as much as 10 feet on the region by Sunday night.

The potent system is also bringing high winds to the mountains, triggering a rare blizzard warning for a 300-mile stretch of the Sierra extending from north of Lake Tahoe to south of Yosemite. The warning went into effect early Thursday morning and will remain in place until 10 a.m. Sunday.

The snow accumulations are forecasted to be particularly high between Friday evening and Saturday morning with between 2 to 5 feet expected for Plumas, Sierra and western Lassen Counties. Localized amounts of snow between 5 to 10 feet were projected near Lassen Park, Yuba Pass, and Lake Davis. 

KPIX First Alert Weather: Current conditions, alerts, maps for your area

Lake Tahoe communities can expect snow accumulations between 3 and 6 feet, with 6 to 10 feet at elevations above 7,000 feet. In the area around Reno, Virginia City and Sparks, snow accumulations of 6 to 14 inches are forecasted for the valley floors and up to 2 to 3 feet for Virginia City, the Virginia Highlands, and foothills above 5000 feet.

What is driving the upcoming Sierra storm’s supercharged snow totals? 06:22

According to CBS News Bay Area meteorologist Darren Peck. The colder temperatures associated with the storm will essentially "super-charge" the volume of snowfall. While it usually takes about 10 inches of snow to yield one inch of water in the Sierra, this storm will produce snow that is instead at a 15-1 ratio. The higher ratio producing more snow with less water content is due to the detailed crystals from the colder temperatures containing more air, allowing the snow to pile up 50% higher and faster due to that increased ratio.

The lead scientist at a snow lab atop the Sierra said it's possible they could break their modern-day record of about 3.5 feet of snow in a single day from back in 1989.

"It's a very serious storm for us," Andrew Schwartz said Wednesday from UC-Berkeley's Central Sierra Snow Lab, founded in 1946 in Soda Springs, California, northwest of Lake Tahoe.

Schwartz added that he's been watching the computer models over the past two weeks and, if anything, thinks the National Weather Service's snowfall predictions are conservative.

"The forecasted total at the snow lab of 6 to 9 feet is on the lower side of what the models are suggesting," he said.

Several ski resorts have announced closures on Thursday, including Donner Ski Resort, Ski Heavenly and Mt. Rose. Sierra-at-Tahoe closed early at noon and announced it would remain closed Friday.

On Thursday afternoon, officials at Yosemite National Park announced the park would close Thursday at midnight due to safety concerns over the storm. The announcement on social media said park would remain closed at least through 12 p.m. Sunday and possibly later. Visitors currently in the park were advised to leave as soon as possible and no later than 12 p.m. Friday, March 1.

The arctic air from the Gulf of Alaska will also dramatically lower the elevations where snow is falling, not only in the Sierra but across Northern California where there could be a dusting of snow at higher peaks in the North Bay and the South Bay including the Santa Cruz Mountains. 

Snow is forecast for elevations above 2,000 feet and a few inches are forecast for Mt. Diablo in Contra Costa County, according to the national weather service.

While the storm will make for inadvisable travel through the Sierra, the large quantity of snow expected will have some positive benefits.

The results of the latest statewide snow survey released Thursday showed California's water supply potential is improving after a slow, dry start to the rainy season.

After conducting the season's third Sierra Nevada snowpack survey, DWR officials announced that the "water equivalent," how much water is in the snowpack, is 80 percent of average for this time of year.

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