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The first widespread snowstorm of the season is set to excite winter enthusiasts but can cause some travel problems from the Rocky Mountains to the northern High Plains in the upcoming days.

After soaking the Pacific Northwest to end Friday, the storm is expected to track slowly through the Rockies and onto the High Plains this weekend and into Monday.

Small-scale storms have brought snow to parts of these regions already this season, including as recently as Friday. This storm, however, is expected to bring the most far-reaching swath of snow since last winter.

Snow will initially fall in the mountains early in the weekend before spreading to the lower elevations of the northern Rockies and northern High Plains Sunday into Monday.

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Billings, Montana; Gillette, Casper and Cheyenne, Wyoming; Rapid City, South Dakota; and Dickinson and Williston, North Dakota; are among the cities expected to receive some snow during the upcoming days.

Average highs in each of these cities are in the lower 60s this time of year.

A little snow may just graze Billings as snow can leave a couple to several inches in the lower elevations from Casper to Dickinson Sunday into Monday morning.

"Due to warmth stored up in paved surfaces, the snow may initially melt on roads and sidewalks," according to AccuWeather Senior Meteorologist Brett Anderson. "However, travel conditions may deteriorate if the snow can fall hard enough to overcome that melting."

Motorists are being advised that stretches of interstates 25, 90 and 94 can become slushy and slippery. Treacherous travel may also unfold in the passes along I-70 and I-80 through the central Rockies.

In the mountains, Anderson anticipates an AccuWeather Local StormMax™ of 24 inches this weekend and into early next week.

"This is the first major storm of the season so people may not take as many precautions as they would during the winter," Anderson said. "People need to slow down and leave space between other drivers."

The potential for slick travel and disruptions to daily routines may continue to plague areas from Wyoming to the western Dakotas beyond Monday morning.

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If the storm takes a more northerly track, snow may persist over these areas through Monday and into Tuesday.

Another scenario is that this corridor dries out for a time early next week as the mountain snow focuses on the southern Rockies. Snow may then spread back over the region at midweek.

"The wet nature of the snow coming to the region can weigh down some trees in the lower elevations and lead to sporadic power outages," Anderson said.

Issues can be more widespread if the scenario in which the snow persists into early next week rather than a break between snow events pans out.

In the latter solution (the northern Rockies and High Plains drying out), snow may fall in Denver to start the new week if enough cold air plunges southward.

Regardless of which scenario unfolds, Denver and the entire I-25 corridor is expected to escape the rounds of flooding rain threatening the Plains.

The storm can also kick up gusty winds across Nevada and the Desert Southwest for the second half of this weekend as rain returns to Arizona. Any heavier rain can trigger new flash flooding with the ground still saturated after Rosa's soaking.

The upcoming week as a whole will not feel like typical October weather, even after the snow stops falling in the northern Rockies and northern High Plains. Highs will be held to the 30s and lower 40s in these areas on most days.

More snow may enter back into the picture over a part of the Rockies later next week. The location of this snow will be determined by how far south another shot of colder air presses and interacts with moisture from Sergio.