A winter storm will bring heavy snow to the western United States.

(CNN) — More than 10 million people in at least nine western states, including cities like Seattle and Salt Lake City, are under winter watch.

The storm will bring up to 30 inches of snow to the drought-stricken Sierras but will make travel “difficult or impossible.”

Winter storms will bring more difficult and impossible travel through the Sierra through Sunday.” The National Weather Service (NWS) office in Reno said..

Snow and rain will begin to taper off for most areas on Friday before the next storm system moves in late Saturday/early Sunday.

Snow rates will reach 2 to 3 inches per hour Thursday and early Friday. This, combined with high winds, will lead to near-zero visibility.

The beginning of winter

“The weather today is the first day of winter and it feels like it in the Pacific Northwest,” the NWS Portland office said.

While California will get about 1 meter of snow, places like Montana, Utah and the Colorado mountains are expecting 12 to 24 inches of snow. Coastal areas may experience heavy rainfall of over 100 mm.

A mix of rain and snow is expected in cities like Seattle and Portland. While this will limit the amount of snow that accumulates on the ground, slushy roads will cause travel problems, and sub-zero temperatures will create black ice.

For downtown Seattle, only 1 to 2 inches of snow is expected through Saturday, with a winter weather advisory through Friday night. This is significant snow and very rare for Seattle, a city that averages (9 cm) of snow per year, as does Little Rock, Arkansas. In fact, Seattle could record more than half of its annual snowfall from this early winter storm.

A winter weather advisory has also been issued for Billings and Missoula, Montana, where snowfall amounts of 2.5 to 7 cm and 7 to 15 cm are predicted, respectively.

Reno, Nevada, all altitude. In the city and on the slopes, 2.4 to 10 cm is expected, but if you go above 5,000 feet, the forecast is 7 to 17 cm.

Salt Lake City will also record a few inches of snow, with 2 to 4 inches expected. However, in the mountains, including Park City, totals will be closer to 12 inches.

Aspen, Colorado, is under an avalanche watch through Saturday morning, when skiers can expect 5 to 10 inches.

Winter storms will bring more difficult and impossible travel through the Sierra through Sunday. See our Winter Storm Warnings for more information: https://t.co/Hlck0YYqz8. Check Caltrans for the latest road information: https://t.co/rYQgfWT4N2. #Cawks pic.twitter.com/E2egHY3G8Q

—NWS Reno (@NWSReno) November 30, 2022

The heaviest snow will fall in the Sierra Range, with 20 to 30 inches predicted for places like Mammoth Mountain and Mount Shasta.

Therefore, the NWS office in Reno It urges people to avoid non-essential travel during high-impact periods.

Fast start to winter, still a long way to go

Although it causes a lot of displacement problems, all that snow is good for one thing: helping with drought. But one blizzard doesn’t mean the entire season will be the same.

Last year, California had its wettest start to the year in more than 40 years. However, precipitation quickly plateaued and the season’s snow cover was only 35% of what would normally be expected.

Regarding the snowfall conditions in the region at this time, the SNOTEL Network The Natural Resources Conservation Service reports the following snow-water equivalent percentages for the region in its most recent update (Nov. 29):

Pacific Northwest 134%
California 135%
Great Basin 157%
Lower Colorado 152%
Upper Colorado 98%

While these numbers are a great start, they need to stay the same to have a major impact on the drought conditions and water supplies that have plagued the West for decades.

CNN’s Rob Shackelford contributed to this report.