Extremely cold weather isn't going away soon for a swath of the United States from Texas to New England, as impacts from a deadly winter storm linger.

The monster storm has already dumped sleet, freezing rain and snow over much of the country, disrupting travel and leaving hundreds of thousands of homes and businesses without power in eastern and southern states. Now, widespread subzero temperatures and wind chills are expected to keep impacting millions of Americans into late January.

Authorities reported at least 13 deaths over the weekend as frigid temperatures expanded over the eastern two-thirds of the nation. As of Monday morning, more than 760,000 power outages have been reported.

The National Weather Service said heavy snow was forecast from the Ohio Valley to the Northeast Monday morning, including up to 18 inches in parts of New England. Forecasters also predicted that "catastrophic ice impacts" will linger and will likely result in extended power outages.

"Bitterly cold temperatures and dangerously cold wind chills" were expected from the Southern plains to the Northeast, causing "prolonged hazardous travel and infrastructure impacts" through the week, according to the weather service. Forecasters noted that dangerous wind chills as low as 50 degrees below zero and "below-normal" temperatures may continue into early February.