More than a dozen states sound the alarm, declaring emergencies or urging people to stay home.

More than 8,000 flights set to take off over the weekend have been cancelled as a major storm bears down across the United States, threatening widespread heavy snow and a band of catastrophic ice stretching from east Texas to North Carolina.

At least 3,400 flights were delayed or cancelled on Saturday, according to the flight tracking website FlightAware, and more than 5,000 were called off for Sunday.

Roughly 140 million people from New Mexico to New England were under a winter storm warning, as forecasters say damage, especially in areas pounded by ice, could rival that of a hurricane.

Snow fell ‍over parts of Texas, Oklahoma and Kansas on ‍Friday ahead of a winter storm expected to converge with bitter Arctic cold and engulf much of the US over the weekend.

“This is a mean storm,” Jacob Asherman, a meteorologist at the US Weather Prediction Center in Maryland, told Reuters news agency. He said it was the biggest so far this ​season in terms of intensity and scope.

Life-threatening wind-chill readings had plunged to below minus 45 degrees Celsius (minus 50 degrees Fahrenheit) in the Dakotas and Minnesota. The meteorologist warned that exposure to such cold without proper clothing “can lead to hypothermia very, very quickly”.

The ‍worst was predicted for parts ⁠of Louisiana, Mississippi and Tennessee, where ice up to an inch thick was likely to coat tree limbs, power lines and roadways, Asherman said.

Governors in more than a dozen states sounded the alarm, declaring emergencies or urging people to stay home. Texas Governor Greg Abbott told residents on X that the state Department of Transportation was pretreating the roads and urged residents to “stay home if possible”.

Utility companies braced for power outages because ice-coated trees and power lines can keep falling long after a storm has passed.

President Donald Trump said via social media on Friday that his administration was coordinating with state and local officials and that the Federal Emergency Management Agency was “fully prepared to respond”.

The storm represents the ‍first major test for New York City Mayor Zohran Mamdani, who took office just weeks ago.

He told local news station NY1 on Friday that the city’s sanitation workforce would transform into “the nation’s largest snow-fighting operation” in advance of the heavy snowfall expected on Sunday.