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Winter storm and blizzard warnings continue to be in effect as a winter storm now in the Rockies is poised to intensify in the Plains, and will eventually spread snow and wind into the Great Lakes and interior Northeast through this weekend.

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Blizzard warnings are now posted for parts of eastern South Dakota, southeast North Dakota, and western Minnesota. Winter storm watches and warnings stretch from the Rockies to northern Minnesota.

Snow is currently blanketing parts of the Rockies, and is also beginning to sweep into the northern High Plains as the system intensifies.

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Locally up to a foot of snow had fallen in parts of Wyoming and southern Montana as of late Thursday morning, local time.

The first snow of the season fell in the Salt Lake City metro area early Thursday, with some enhancement by wind flow over the Great Salt Lake, slickening roads for the Thursday morning commute in some areas.

Accidents and slide offs from the snow . Interstate 80 in Wyoming .

Denver saw its first snow of the season just before noon on Thursday.

An area of low pressure will now track from the central Plains to northern Great Lakes through Friday while intensifying. Locations northwest of where that low-pressure system tracks will see accumulating snow.

High winds will accompany the snow in the northern Plains, creating dangerous driving conditions due to poor visibility and snow-covered roadways.

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This weekend, a secondary area of low pressure may form over the interior Northeast or eastern Canada, producing a round of snow in the interior Northeast and Great Lakes snowbelts.

Here's the general timing for the snowfall as the storm system moves east, followed by a look at possible accumulations.

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Thursday-Friday Forecast

Snow will spread into the High Plains and northern Plains of southern Montana, Wyoming, the western Dakotas and western Nebraska, as well as the high country of Colorado Thursday. Winds will also intensify in these regions, producing areas of reduced visibility.

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Thursday night into Friday, any rain will change to snow in the eastern Dakotas, central Nebraska and northern Minnesota. As the surface low intensifies, strong north to northwest winds could produce blizzard conditions in open country. Travel could become increasingly treacherous and some road closures are possible.

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Friday night, snow and strong winds will persist in the Arrowhead of Minnesota, far northern Wisconsin and spread into the Upper Peninsula of Michigan. Snow will end in the northern Plains.

This Weekend

This weekend, a multi-day period of lake-effect/lake-enhanced snow is likely over the Great Lakes snowbelts –the first real such event this season – as a gyre of low pressure taps cold air from Canada.

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Moisture wrapping around that secondary, sprawling Québec low will also wring out snow not just over the higher elevations of the Northeast, but also in some lower elevations of the interior from West Virginia to the Mohawk Valley and northern New England. This snow is expected to continue through Monday in some areas.

How Much Snow Will Fall?

Rockies

The heaviest accumulations are expected in the higher elevations of far southern Montana and Wyoming (Bighorns, Absaroka, Wind River), and Rockies of Colorado.Lighter, but still significant accumulations are expected in the Wasatch, as well as adjacent lower elevations of southern Montana, Utah, Wyoming and Colorado.

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Northern Plains

The heaviest snow is expected over a swath of northern and western Minnesota and eastern South Dakota. Over a foot of snow may pile up in a few parts of northern Minnesota.More moderate snow totals are expected to the west over the central and western Dakotas into western and central Nebraska.As mentioned earlier, high winds coupled with falling snow may lead to blizzard conditions, at times, particularly over open country. Expect road closures, including sections of major interstates.

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Northeast/Great Lakes

The potential heaviest snow accumulations this weekend through Monday are targeting higher elevations of northern Vermont, northern New Hampshire, New York state, northwest Pennsylvania, and West Virginia, as well as the eastern Great Lakes snowbelts.Some locally heavy accumulations can't be ruled out in the Lake Superior and Lake Michigan northern snowbelts, as well.Winds near the Lake Superior shore Saturday could produce whiteout conditions, at times.Some accumulations are also possible in some larger cities outside of the areas of heaviest lake-effect, lake-enhanced snow from northeast Ohio to the Upper Hudson and Mohawk Valleys of New York.No accumulations are expected along the I-95 corridor from Maine to Virginia.

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An Abrupt Reality Check

This will certainly be after across theRockies, Plains and upper Midwest.

For many cities east of the Rockies, this would be the season's first accumulating snow. Here's a list of the average first date of accumulating snow in those locations:

: October 2: September 30: October 16: October 26: November 2: October 18: October 13

Be sure to check back with weather.com for updates throughout the week as we iron out the details on this potential winter storm.

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MORE ON WEATHER.COM: Winter Storm Troy, March 2016

Cars crawl along 12th Street on Wednesday morning, March 30, 2016, in central Casper, Wyoming, after a spring storm dumped snow over most of central Wyoming overnight, leading businesses, roads and schools to close. (Dan Cepeda/Casper Star-Tribune via AP)

At a Glance

An expansive winter storm will bring snow, wind from the mountain West to the interior Northeast.Winter storm and blizzard watches have been posted in the Plains and upper Midwest.Dangerous driving conditions are likely in the northern Plains.Weekend snow will then blanket parts of the interior Northeast and Great Lakes snowbelts.