Game-time temperature was 13 below zero, with wind chills making it feel like 48 below.

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Temperatures should be below freezing overnight, with wind chills making it feel like -15 degrees Fahrenheit.

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Residents of Rugby, North Dakota, suffered through wind chills of 51 degrees below zero early Monday morning.

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Temperatures at the 5:30 CST kickoff are forecast to be in the single digits, with wind chills falling below zero.

FORBES: The NFL's Coldest Games

Despite wind chills that have dipped to 35 below zero outside, it is warm inside, and business has been good, she says.

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Wind chills on the mountain dipped to minus 85 on Wednesday.

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Some of the worst winter weather on record occurs in Mid-February, and right now it looks like Sunday is going to be one of the coldest days of the entire year, with very uncomfortable wind chills.

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