The massive size and intensity of this snowstorm is unheard of for October.

Both Denver and Minneapolis could see their first snow of the season.

The National Weather Service called it a "potentially historic October winter storm."

A "potentially historic" winter storm will slam the north-central USA over the next few days with up to 2 feet of snow possible in some areas.

Snow will accumulate from eastern Washington and Montana to Colorado, the Dakotas, Minnesota and northern Wisconsin, the Weather Channel said. Record low temperatures are also possible Thursday and Friday across the western USA.

The system will produce severe storms and heavy rain Thursday in the southern Plains and critical-to-extreme fire weather threats from the central and southern Rockies to California, the National Weather Service said.

The size and intensity of this snowstorm are unheard of for October, according to AccuWeather.

In Spokane, Washington, wet, heavy snow snapped tree branches and took out power lines. Avista Utilities was restoring power to 32,000 customers on Wednesday.

Driving conditions are deteriorating across Montana and northern Wyoming as ice and blowing snow covered roadways.

Related:A snowstorm will wallop central USA this week, plunging temps as much as 60 degrees in one day

A slew of winter storm warnings, watches and freeze warnings were in effect across parts of seven states as the storm ramped up Wednesday, AccuWeather said.

Significant travel disruptions, tree damage and sporadic power outages will be possible where the heaviest snow occurs, the weather service in Grand Forks, North Dakota, warned.

Denver and Minneapolis could see their first snow of the season, the Weather Channel said.

The storm will have two parts, the first of which is targeting the northern and central Rockies and High Plains on Wednesday into Thursday. The second part will bring snow to the eastern and central portions of the Dakotas and western Minnesota by week's end.

"Near-blizzard to full-fledged blizzard conditions are possible across portions of central North Dakota Friday afternoon into Saturday morning," the weather service in Bismarck said. "Expect high impacts and dangerous to impossible travel conditions."

The weather service called it a "potentially historic October winter storm."

The Weather Channel has named the storm Winter Storm Aubrey, the network's first named storm of the season.

Wild temperature swings will accompany the storm. In Denver, temperatures are forecast to plummet from the summery low 80s on Wednesday afternoon to the frigid upper 20s by Thursday morning.

A number of daily record lows will be in jeopardy in such cities as Denver; Portland, Oregon; and Salt Lake City on Thursday and Friday.

This storm comes just a little more than a week following the first blast of winter across the northern Rockies, according to WeatherBug. A storm at the end of September racked up 4 feet of snow in Browning, Montana, 19.3 inches at Great Falls, Montana, a foot in Jackson Hole, Wyoming, and 9 inches in Post Falls, Idaho.

Contributing: The Associated Press