U.S. Issues Alert for Extreme Cold Expected in December

Extreme cold arriving in December

Polar vortex under monitoring

Thermal anomalies predicted

Meteorologists do not yet have a detailed forecast ready, but there is growing consensus that December will be extremely cold in parts of the United States.

The Climate Prediction Center of the National Weather Service indicates that colder-than-normal conditions are more likely in the northern and northeastern regions of the country.

Some forecasters believe that a complex interaction involving the polar vortex could send some of the coldest air on Earth into the United States.

A Frigid December Signals Extreme Cold in the US

Lots of hype about the #PolarVortex but is it deserved? Our AI subseasonal model, which I can credibly claim as world’s best is predicting that the most expansive region of most likely extreme #cold on earth stretches from the Canadian Plains to the US East Coast 3rd week of Dec. pic.twitter.com/BeL2jgjKuF

— Judah Cohen (@judah47) November 23, 2025

Climatologist Judah Cohen, a research scientist at MIT, told USA TODAY via email that “the cold of the first week of December is the appetizer, and the main course will come in mid-December.”

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According to Cohen, his computer model — “which I can credibly claim is the best in the world” — predicts that the largest and most likely zone of extreme cold on Earth will stretch from the Canadian Plains to the US East Coast in the third week of December.

Signs indicate the situation could worsen as weeks progress, though experts remain cautious about the potential magnitude of this phenomenon.

An Uncertain Outlook for Snow

Some of Earth’s most extreme cold may be headed for the US in December https://t.co/1BA2OpQuaE

— USA TODAY (@USATODAY) November 27, 2025

As for snowfall, it remains unpredictable.

Snow-producing weather systems generally cannot be forecast more than a few days in advance.

The presence of cold air is only half the equation, so actual accumulation will depend on atmospheric interactions that are still unclear.

Weather Trader meteorologist Ryan Maue noted in a Substack post that the main mass of extremely cold polar vortex air will remain nearly stationary over Canada for the next seven to ten days.

Maue continues to monitor the risk of the polar vortex dipping into the lower 48 states as December progresses.

Cohen added that large-scale atmospheric patterns occurring high above the surface — including the polar vortex and the phenomenon known as sudden stratospheric warming — will determine the intensity and duration of the cold.

However, he acknowledged: “I have doubts about what exactly is happening with the polar vortex.”

Cold Intensifies at the Start of December

Although the most extreme cold will not arrive until later in the month, widespread and persistent below-average temperatures are expected across a large portion of the country.

The National Weather Service warns that colder conditions will impact the Western High Plains and the East Coast next week.

In contrast, southeastern states will see near-average conditions, while Florida will experience warmer temperatures.

The coldest anomalies for high and low temperatures are forecast for the Midwest on Monday, December 1, and Tuesday, December 2.

Many areas are expected to see highs in the 10s and 20s (°F), with lows near 0°F reaching northern Missouri and Illinois as the Arctic air mass settles in.

The NWS added that subzero nighttime temperatures are possible from eastern Montana to North Dakota — reinforcing the urgency of the extreme cold December forecast.