Millions of Americans forced into an involuntary polar plunge this week

After a mild end to the weekend for many states, Old Man Winter will make a comeback as we start off the new workweek.

"Temperatures will be 10 to 20 degrees below average over the northern tier states by Monday morning,"

The thermometer will slip to 30 to 40 degrees below normal by Tuesday and Wednesday

As a strong high pressure system begins to spread Arctic air farther south and east.

Denver will go from a high temperature in the low 60s Sunday all the way down to 15 for the peak Tuesday

Rapid City, SD will slide from a high of 50 degrees Sunday to 0 degrees for a high Tuesday.

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