• Two separate storms will blanket much of the mountain West with snow through the weekend.
  • The heaviest snow will fall in California’s Sierra Nevada, with multiple feet of accumulation.
  • Rain is also expected in lower elevations of California, but it won’t produce widespread flooding.
  • Light snow, driven by winds, could lead to tricky travel in the Northern Plains Friday.

A​ pair of storms will dump feet of heavy snow in California’s Sierra Nevada through the weekend and could also cause travel problems in other parts of the West and Northern Plains.

T​he first storm, named Winter Storm Carli by The Weather Channel, has already had significant impacts in the Pacific Northwest.

While up to 2 feet of snow has already fallen in the Washington Cascades, Carli’s snow hasn’t exclusively been in the high country.

S​eattle picked up its first accumulating snow of the season, with amounts ranging from an inch near downtown and SeaTac Airport to 6 inches in the King County foothills and Snohomish County.

T​his combination of wet snow and strong winds knocked out power to over 60,000 in the metro Tuesday into Wednesday.

R​ight now, that system is still producing snow over parts of the Northwest and northern Rockies.

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W​inter storm warnings and winter weather advisories are posted from Washington state to California eastward into the northern Rockies. Among areas in winter storm warnings are the Cascades, Sierra, Bitterroots, and parts of eastern Washington, including the city of Spokane.

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F​orecast Timing

A​gain, there are two storms we’re tracking. The first is currently impacting the West. The second will dive southward from Alaska and arrive along the Northwest coast later Friday, then have impacts in other parts of the West into the weekend.

H​ere’s a daily look at what to expect:

T​hursday

Heavy snow in California’s Sierra, along with high wind gusts. Heavy snow in the northern Rockies will spread into Utah’s Wasatch mountains. Lingering snow in the Cascades tapers off. Rain in Northern California, locally heavy in a few spots, will spread to Southern California at night.

F​riday

Snow and gusty winds will spread through the Northern Plains and northern Great Lakes through Friday night. The second storm brings rain and mountain snow to the Northwest.

R​ain and Sierra snow should return to Northern California Saturday. Once again that Sierra snow could be heavy. Rain and snow showers may linger in much of California through Sunday night, while snow should also spread into parts of the Great Basin and Rockies.

How Much Snow, Rain?

T​he heaviest additional snow totals through early Monday will be in California’s Sierra, where multiple feet of snow are expected.

T​his could make travel treacherous, if not impossible at times, Thursday with the first storm, then again from later Saturday into Sunday with the second storm.

A​dditional 1-foot snow totals are also expected in parts of the northern Rockies. While snow totals will be modest, the combination of snow and strong winds in the Northern Plains from eastern Montana through the Dakotas into northern Minnesota and northern Wisconsin could also lead to difficult driving conditions Friday and Friday night.

R​ainfall totals from both storms combined are expected to be generally in the 1 to 2-inch range in Northern California and an inch or less in Southern California. While there may be some nuisance flash flooding in urban, flood-prone areas and some landslides or debris flows from recently-burned areas, widespread flash flooding is not expected.

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D​rought Relief: ‘Goldilocks Scenario’

No storm, or pair of storms in this case, will be nearly enough to quench the multi-year drought ​gripping California and other parts of the West.

But this particular pair of storms is a “Goldilocks setup” to chip away at this long-term drought.

First, they won’t be too warm or wet to produce widespread flooding in lower elevations and rain in some higher elevations. These so-called atmospheric river events can be more of a curse than a blessing for California drought relief.

Secondly, t​hese systems also won’t come through mainly dry, which can lead to strong winds that can rapidly spread wildfires and further dry out already parched vegetation.

I​nstead, this stormy pair will deposit fresh Sierra snowpack that, when melting in spring, helps to replenish California’s reservoirs, a key source of water for millions. A​s of Nov. 30, Sierra snowpack was already up to 42% above average for that time of year, before any new snow arrived.

T​hey’ll also soak the ground at lower elevations, but not excessively so, knocking down the fire danger from parched ground, for awhile.

S​o, while it will create some travel headaches over the next few days, this setup is one positive step among many needed to battle the multi-year drought.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

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