A cross-country skier in falling snow in the Saratoga Spa State Park on Wednesday, Jan. 21, 2026, in Saratoga, New York.

Already, a bitter burst of cold is gripping much of the country, and in the next few days, it will reach at least 45 states and extend across two-thirds of the country. It is one of the most extreme winter storms in years.

The National Weather Service on Thursday warned that “dangerously cold and very dry Arctic air” will spill into the continental United States and lead to “life-threatening risk of hypothermia and frostbite” as temperatures drop well into negative territory, creating some of the coldest weather on Earth.

For millions of Americans, this is not just a forecast anymore.

Schools were already announcing closures around the country Thursday morning. Lines were forming at grocery stores. The Texas power grid operator issued a winter warning as it braces for higher electricity demand and disruptions from freezing rain.

Wintertime cold is normal. But what is unusual is how this kind of cold tends to arrive: These icy spells sneak up on us, posing a greater challenge to forecasters and leaving little time to prepare compared to slower-moving extremes like heat waves.

“Oftentimes, longer duration signals, such as heatwaves, can be more predictable, whereas short bursts of cold are more difficult to predict,” Matthew Rosencrans, meteorologist at the National Weather Service’s Climate Prediction Center, told Vox in an email.

Cold snaps are especially jarring when they’re interspersed with milder weather. And even though the planet just came out of one of the hottest years on record and is poised to heat up more, shocks of extreme cold are not going away, nor are their disruptions and dangers. Winter Storm Uri in 2021 cost the US economy more than $200 billion as........

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