A massive winter storm swept across the United States, disrupting travel and leaving hundreds of thousands without electricity. More than 4,000 flights were cancelled on Sunday as the storm moved from the southern states to the Northeast.

The National Weather Service warned that the storm, bringing snow, sleet and freezing rain, could affect nearly 180 million people, over half of the US population, from the southern Rockies to New England.
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Top points
- Washington, New York and Boston are expected to see 1 to 2 feet (30–60 centimetres) of snow in the coming days.
- According to poweroutage.us, over 840,000 customers were without electricity on Sunday morning, with Tennessee hardest hit at more than 300,000 outages. Texas, Louisiana and Mississippi each recorded over 100,000 customers without power.
- Airlines struggled to cope with the severe conditions, warning passengers of widespread delays and cancellations at major airports. Road travel has also become hazardous, with sleet and icy conditions making journeys dangerous across large swathes of the country.
- The storm is expected to persist into the week, bringing frigid temperatures, heavy snowfall, sleet and freezing rain to the eastern two-thirds of the nation.
- Authorities have urged residents to exercise caution and avoid non-essential travel.
Freezing weather disrupts Texas refineries
Freezing temperatures in the United States are causing major disruptions to both energy production and the electricity grid.
{{/usCountry}}Freezing temperatures in the United States are causing major disruptions to both energy production and the electricity grid.
{{/usCountry}}Exxon Mobil Corp. has temporarily shut down some equipment at its Baytown, Texas, oil refinery, one of the largest fuel-making facilities in the country, located about 30 miles east of downtown Houston.
Celanese Corp. also reduced operations at its Houston-area plant as the severe weather continued.
The Houston Ship Channel, which provides access to the region’s refineries, export terminals and chemical plants, was closed to all vessel traffic at 6 pm local time. A notice from Moran Shipping said the channel will reopen once conditions improve.
In the PJM Interconnection, a major US electricity grid covering areas from Chicago to Washington, power prices surged on Saturday.
(With inputs from agencies)