A fresh blast of Arctic air is poised to spill across a wide swath of the United States, and the latest polar vortex map makes clear which regions are most exposed. Forecast models show a sharp ...

The stratospheric polar vortex, the winter engine that traps Arctic cold high above the North Pole, is entering its seasonal collapse. What’s left is the lower-level polar vortex core, lingering over ...

A forecast map reveals which states can expect to see “persistent cold” in the weeks ahead, after experts said the polar vortex would unleash waves of icy air across parts of the U.S. through January.

This winter’s harsh run in the East is intensifying, with some of the coldest air so far this season plunging into New York this weekend as a mass of Arctic air drops south from Canada. "A brutally ...

Snow season has gotten off to a fast start across swaths of the northern United States this year. Fueled in part by an unusually early disruption to the polar vortex — which is now easing — 18 states ...

The stratospheric polar vortex is collapsing for the season, but its remnants can still bring cold air to the US. The polar vortex dissolves annually as the Arctic warms, reducing the temperature ...