BUFFALO, N.Y. – The season’s first major snowfall blankets towns along Lake Erie in upstate New York and northwestern Pennsylvania amid the hectic holiday travel and shopping weekend, while numbing cold and heavy snow could continue into next week, causing dangers across the Great Lakes, Plains and Midwest regions.

The heavy snowfall has led to an emergency declaration in parts of New York state and a disaster declaration in Pennsylvania, with officials warning of dangerous conditions for Thanksgiving travelers trying to return home.

“Travel will be extremely difficult and dangerous this weekend, particularly in areas where several feet of snow could accumulate very quickly,” the National Weather Service said Saturday.

Parts of major roads in Pennsylvania and New York were closed on Saturday. Nearly 2 feet of snow fell in parts of New York, Ohio and Michigan, and even more snow was recorded in the northwestern tip of Pennsylvania.

Roads in parts of northwestern Pennsylvania became so impassable early Saturday that scores of people sought shelter overnight in the lobby and hallways of a booked Holiday Inn hotel near Interstate 90. Jeremiah Weatherley, a hotel worker, said people rolled in as the snow piled up, with workers opening the hotel’s conference room and giving people blankets so they could sleep on the floor.

“It was difficult to deal with, but we had no choice,” he said. “They just showed up, and we don’t want to turn people away.”

This week’s blast of frigid Arctic air also brought bitterly cold temperatures 10 to 20 degrees below average to the Northern Plains, the weather service said.

Parts of Michigan were hit by the heavy lake-effect snow, which occurs when warm, moist air rising from a body of water mixes with cold, dry air above. Bands of snow that had been rolling off Lake Superior for three days had buried parts of Michigan’s Upper Peninsula under 2 feet or more of snow by midday Saturday, said Lily Chapman, a meteorologist at the National Weather Service office in Marquette, Michigan.

The record snowfall, which totaled 24.8 inches in Gaylord, Michigan, is good news for Treetops Resort ahead of its opening next weekend, said Doug Hoeh, the resort’s recreation director.

“When that much snow falls, of course it’s good for the snow-covered hills, but bad for the parking lots, so we’re digging out, so to speak. But we’re getting close to starting skiing and the natural snowfall is definitely helping,” Hoeh said.

In Pennsylvania, Gov. Josh Shapiro signed a declaration of a state of disaster emergency. He said nearly 3 feet of snow had already fallen in parts of Erie County in northwestern Pennsylvania and more snowfall was expected through Monday evening. Pennsylvania State Police responded to nearly 200 incidents from 6 a.m. Friday to 6 a.m. Saturday, officials said.

Associated Press writers Thompson reported from Buffalo and Izaguirre from Lindenhurst, N.Y. AP writers John Wawrow in Orchard Park, N.Y.; Freida Frisaro in Fort Lauderdale, Florida; Ron Todt in Philadelphia and Holly Ramer in Concord, NH, contributed to this report.