SALT LAKE CITY — Utah’s mountain snowpack is about to get another boost.

The National Weather Service’s Salt Lake City office has issued another winter storm warning for Utah’s mountains, ahead of a storm that has the potential to deliver yet another foot or more of snow this weekend.

The agency’s warning covers the Wasatch Mountains through southern Utah, including the west Uintas. It goes into effect at 11 a.m. Saturday and remains in place through late Sunday afternoon. Up to 18 inches of snow or more are possible for northern and central Utah mountains, while the mountains in southern Utah are forecast to receive a little less, according to the alert.

It's been an unusually wet water year across the #ColoradoRiver basin, with numerous stations across #Utah and #Colorado reporting snowpack numbers that rank in the top 5 wettest years. #utwx #cowx pic.twitter.com/RUisy2np0g

— Colorado Basin RFC (@nwscbrfc) January 13, 2023

The system is the result of another pattern from the West, much like the past few storms that have rocked Utah, said KSL meteorologist Kristen Van Dyke. A major low-pressure system located in the Pacific Ocean is drawing tropical moisture and moving it into California, Oregon and Washington. Those storms then move into Utah.

“It’s pulling it into these storm systems as they roll into the West Coast,” she said. “That’s what you’ve been hearing about with this atmospheric river. It’s just this really deep moisture source … so they wring out just lots of heavy (precipitation).”

The system is forecast to arrive Saturday afternoon, bringing valley rain and mountain snow. Some upper-valley communities may see a mixture of rain and snow, Van Dyke said. She adds the storm is expected to intensify overnight into Sunday morning, which is when valley areas will begin to receive snow, as well.

Federal meteorologists also issued a winter weather advisory for parts of the Wasatch Back, like Heber City, Huntsville and Park City. Those areas are forecast to receive 5 to 10 inches of snow between Saturday and Sunday. Higher amounts are possible in the Ogden Valley, the alert states.

Meanwhile, the weather service’s Grand Junction, Colorado, office issued a winter weather advisory for the La Sal and Abajo Mountains, where 5 to 10 inches of snow or more are possible, as well.

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A National Weather Service snowfall model updated Friday afternoon only lists 1 to 3 inches of snowfall throughout most of Utah’s valley communities, while a KSL Weather model lists the potential of 3 to 7 inches by Monday morning. Van Dyke explains that it will all depend on when, and if, the rain transitions into snow, which has altered valley accumulations over the past few weeks.

Both weather service alerts advise that traveling might become “very difficult” at times by mountain passes because of the heavy snow expected Saturday and Sunday. Van Dyke adds that Sunday may be a particularly difficult day to travel.

“It’s just going to be a messy day,” she said.

Another storm system is currently forecast to arrive Monday afternoon, providing even more precipitation. The recent run of storms has helped Utah’s mountain snowpack totals surge to 13.1 inches of water across 114 sites in the state. That’s 189% of the normal for mid-January, according to Natural Resources Conservation Service data.

It’s a completely different story from last year. The total, as of Friday evening, is already over 1 inch higher than the 2022 peak, and it’s only 2.7 inches below the normal peak of the past 30 years.

Full seven-day forecasts for areas across Utah can be found online, at the KSL Weather Center.