Frigid temperatures engulfed Texas and other parts of the South on Monday ahead of a rare winter storm expected to bring heavy snow and disruptive ice accumulations to the region into Wednesday, sending residents scurrying to insulate pipes, check heating systems and stock emergency kits.

In Texas, William P. Hobby Airport and George Bush Intercontinental Airport in Houston announced Sunday night that flight operations would be suspended Tuesday in anticipation of hazardous conditions.

Meanwhile, people in the Northern Plains to the tip of Maine were experiencing bitter cold Monday as an Arctic air mass caused temperatures to plunge well below normal lows with dangerously cold wind chills, while the East Coast contends with a thick blanket of snow.

Winter storm warnings stretched from Texas to Florida, with heavy snow, sleet and freezing rain expected in the region into Wednesday. Heavy lake-effect snow was expected in western New York state through Wednesday morning, with 1 to 2 feet possible in some areas, including Oswego along Lake Ontario.

Marc Chenard, a meteorologist with the National Weather Service in College Park, Maryland, projected that as many as 70 million residents will be under some kind of winter storm warning in the coming days.

The lower temperatures will dip into the South early this week, where as many as 30 million people starting Monday could see a wintry mix of snow, sleet and freezing rain. The unusual conditions are expected to stretch from Texas into northern Florida and the Carolinas.

Winter storm warnings were in effect Monday in Texas, Mississippi, Alabama and the Florida Panhandle. The storm was expected to affect Texas on Monday evening, then spread eastward through Wednesday morning with heavy snow expected along and to the north of the Interstate 10 corridor, with sleet and freezing rain in south Texas, southeast Georgia and northern Florida.

Numerous freeze warnings were in place in northern Florida and along much of the Gulf Coast. Forecasters warned that the subfreezing morning lows will pose a risk to sensitive vegetation and exposed plumbing in areas not accustomed to harsh winter temperatures.

Across Louisiana, officials were urging residents to “stay home, don’t go sightseeing” once the storm and the subfreezing temperatures hit, warning that travel could be treacherous as roads ice up and refreeze in the coming days.

The worst weather day is expected to be Tuesday, when the storm hits, and freezing temperatures are expected every night through Friday. Warming centers were being readied, and towns were working to get homeless people off the streets and into safe places. Supermarkets and other stores in many areas have been packed with shoppers stocking up for the bitter cold stretch.

Lakesha Reed, manager of Beaucoup Eats catering in New Orleans, said she planned to leave Tuesday to cook for a Mardi Gras-like event in Washington, but flights were canceled because of the cold weather.

Reed, 47, was born and raised in New Orleans. She said it was in the 30s early Monday afternoon and that near-freezing temperatures are rare there.

“We can barely drive in the rain,” she said. “Last year, we wore shorts for Mardi Gras. We don’t really do seasons here.”

The Electric Reliability Council of Texas issued a weather watch through Thursday due to the extreme cold forecast, increased electricity demand and the possibility of lower backups, but the council said network conditions are expected to be normal.

Much of the Eastern Seaboard will be enduring some of the lowest temperatures this winter.

An area from the Rockies into the Northern Plains will see colder-than-normal weather over several days, with temperatures forecast to drop to between minus 30 degrees to minus 55 degrees Monday.