A powerful winter storm sweeping across large parts of the United States has killed at least 10 people and triggered widespread travel disruptions, power outages, and emergency warnings, as freezing conditions persisted into Monday.
The storm, which dumped snow, sleet and freezing rain across a wide expanse of the country, prompted officials to urge residents to stay off the roads, while an Arctic air mass trailing the system was forecast to drive temperatures to dangerously low levels for several days.
The U.S. National Weather Service (NWS) warned that severe winter conditions would continue into Monday morning, prolonging disruptions to daily life.
In New York, Mayor Zohran Mamdani said five people were found dead over the weekend in freezing temperatures. While he did not confirm the deaths were directly weather-related, he told reporters: “There is no more powerful reminder of the danger of extreme cold.”
In Texas, authorities confirmed three deaths, including a 16-year-old girl killed in a sledging accident. Louisiana’s health department reported two hypothermia-related deaths.
The PowerOutage.com tracking site showed more than 840,000 customers without electricity as of Sunday night, mostly in the U.S. South, where the storm intensified on Saturday.
In Tennessee, where ice downed power lines, more than 300,000 residential and commercial customers were without electricity. Louisiana, Mississippi and Georgia — states less accustomed to severe winter storms — each recorded more than 100,000 outages.
The outages were particularly dangerous as the South was being hit by bitter cold that the NWS warned could set temperature records.
Authorities from Texas to North Carolina and New York urged residents to remain indoors because of hazardous conditions.
“Stay off the roads unless absolutely necessary,” Texas’s Emergency Management Division posted on X.
The storm moved into the Northeast on Sunday, dumping snow and sleet on heavily populated cities including Philadelphia, New York and Boston.
At least 20 states and the U.S. capital, Washington, declared states of emergency. Residents in Washington awoke to several inches of snow on sidewalks and roads, followed by heavy sleet. Federal offices were preemptively closed on Monday.
Several major airports in Washington, Philadelphia and New York had nearly all flights cancelled. Tracking site FlightAware showed more than 19,000 flights into and out of the country had been scrapped since Saturday.
President Donald Trump, who was at the White House during the storm, said on his Truth Social platform: “We will continue to monitor and stay in touch with all States in the path of this storm. Stay Safe, and Stay Warm!”
Meteorologists said the storm was driven by a stretched polar vortex — an Arctic region of cold, low-pressure air that can occasionally deform and send frigid air southward across North America.
The NWS warned that heavy ice could cause “long-duration power outages, extensive tree damage, and extremely dangerous or impassable travel conditions,” especially in states less accustomed to intense winter weather.
Forecasters said life-threatening cold could persist for a week after the storm, particularly in the Northern Plains and Upper Midwest, where wind chills were expected to fall below -50°F (-45°C), temperatures capable of causing frostbite within minutes.

