Winter Weather Warnings Issued for 9 States as 'Massive' Storm Approaches

Winter weather warnings have been issued for nine states in advance of a "massive" Pacific storm that will bring heavy precipitation to the West Coast later this week.

On Wednesday afternoon, various winter weather warnings were in place for Oregon, Washington, California, Idaho, Montana, Nevada, Utah, Colorado and New Mexico. The warnings cited high winds, floods and heavy precipitation ahead of an atmospheric river that will hit the West Coast on Thursday, although rain will begin to fall on Wednesday. A second, more severe storm will batter the West Coast beginning over the weekend.

Atmospheric rivers are defined as a "long, narrow region in the atmosphere—like rivers in the sky—that transport most of the water vapor outside of the tropics," according to the National Oceanic and Atmospheric Administration. More than a dozen atmospheric rivers battered the state last year, largely eliminating drought but creating severe problems such as flooding and mudslides.

As the storm moves inland, it will bring heavy precipitation and strong winds to a slew of states in the West.

"Equally impressive and powerful, check out this ~963 mb low off the West Coast this morning," the National Weather Service (NWS) office in Pocatello, Idaho, posted on X (formerly Twitter) on Wednesday morning. "This massive Pacific storm will continue to bring deep atmospheric river moisture onshore which will reach Idaho starting Thursday into Friday."

NWS meteorologist Erika Cropp told Newsweek that it's not uncommon for an atmospheric river to affect inland states like Idaho or Utah. "We've seen quite a few of those this past year," she said.

An NWS forecast precipitation map showed that the first storm could unleash more than 4 inches of rain on some areas. Northwest Washington, southwest Oregon and northwest California will face the worst of the rain. The storm also is anticipated to bring heavy snow to mountainous regions, such as those near Albuquerque, New Mexico and Hanford, California.

"Heavy snow expected above 5,000 feet. Snowfall 3 to 4 feet above 7,000 feet. Total snow accumulations 2 to 3 feet from 6,000 feet to 7,000 feet," an NWS warning for the Sierra Nevada said. "Snowfall 1 to 2 feet from 5,000 feet to 6,000 feet. Wind will gust as high as 55 mph on exposed ridgetops and along the crest."

Meteorologists are most concerned with the impacts of the second storm. NWS meteorologist Marc Chenard previously told Newsweek that the first system is weakening and moving quickly. But that isn't the case with the forecast for later this weekend.

"The next one looks to be in more of an intensifying phase as it gets closer to the coast," Chenard said. "It is slower moving, so the duration will be longer."

There is uncertainty about the second storm's forecast, as it is still days away.