Biting cold conditions – below-freezing in some areas – will sweep across a large swath of the United States Sunday while heavy, record-breaking lake-effect snow makes post-holiday travel “treacherous” and nearly “impossible” in parts of the Great Lakes region.

A lake-effect storm continued to blanket parts of the Great Lakes region with snow on Saturday, closing highways on one of the biggest travel weekends of the year and prompting Gov. Kathy Hochul of New York to declare a state of emergency on Friday in 11 counties.

From Minnesota to Texas, temperatures were expected to drop by double-digits as cold air swept over the record-warm Great Lakes, bringing the season's first lake effect snowfall. Common in the winter in this region of the US and Canada, lake effect snow occurs when very cold air moves across the relatively warm water of the lakes.