The calendar may still say November, but a wave of snow sweeping across almost 20 states will have residents thinking that winter has already arrived.

So far this autumn, brief bouts of snow could have pushed through the eastern U.S., but very little of it has been prolonged. Now, with a new weather pattern in place, many may find this week's weather much more wintry.

"Unseasonably cold conditions will continue for the center of the country through the eastern U.S. this week, setting the stage for potential wintry weather," said AccuWeather Meteorologist Nicole LoBiondo.

The cold air in place over much of the Plains will hold even as a storm moves out of the Rockies early week, helping to bring a stripe of snow from the northern Texas Panhandle that we saw on Monday, to Indiana on Tuesday.

For many locations, this brought the first snow of the season, including in cities like Tulsa, Oklahoma, and Springfield, Missouri. For others, like the southern suburbs of St. Louis and Indianapolis, this wave of snow comes on the heels of flakes that flew on Saturday.

"Some of the heaviest snow occurred across western Oklahoma where 3-6 inches accumulated" LoBiondo explained.

The highest snowfall total occurred in Elk City, Oklahoma, which is about 105 miles west of Oklahoma City when 7.3 inches of snow fell on Monday.

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LoBiondo explains that, as the storm shifts into the Ohio Valley on Tuesday, the weather pattern becomes more complex as a second storm forms off the mid-Atlantic coast. Together, both storms will cause widespread rain and snow showers from the Upper Midwest to New England coast through Wednesday.

Snow across the Northern Plains and Upper Midwest will be rather intermittent with on-and-off snow showers. Most locations are likely to see between a coating of snow to a couple of inches.

The exception to this will be downwind of the Great Lakes in parts of Michigan, northern Indiana and northern Ohio, where a quick burst or two of snow could bring slightly higher accumulations.

"Across the Northeast, temperatures for most of the Interstate 95 corridor will be marginally too high for snow; instead, accumulating snow will focus in the interior areas of the region," LoBiondo said.

AccuWeather forecasters are predicting widespread 1-3 inches from the Laurel Highlands in southwest Pennsylvania to portions of the Berkshires and into Maine. The highest snow amounts are likely in northern New England and downwind of the eastern Great Lakes, where an AccuWeather Local StormMax™ of 16 inches is possible.

In more southerly locations, precipitation may start off as rain before mixing with and changing to snow. Roadways and sidewalks could begin to turn slippery as early as Tuesday evening in parts of Pennsylvania and the southern tier of New York. Those in New England are expected to wake up to a blanket of fresh snow on both grassy surfaces and roads on Wednesday morning.

As the storm departs, some regions will see snow briefly change over to some freezing rain before switching back to rain.

For those who enjoy outdoor activities during the winter, the dose of early-season snow will come as a blessing.

"Many ski resorts in New England will be gearing up for this storm, dusting off snow-making machines. Natural snow coupled with man-made snow will give ski resorts a good head start to the upcoming ski season, some may even open this week," said LoBiondo.

As the week progresses, the cold will hold across the northern tier of the U.S.; in fact, a reinforced push of cold air is likely before the end of the week. When this cold air rushes over the Great Lakes Thursday night into Friday, locations downwind of the lakes are expected to get another burst of snow.