Add Yahoo as a preferred source to see more of our stories on Google. This winter’s harsh run is intensifying, with some of the coldest air so far this season plunging into New Hampshire this weekend ...

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 ...

Around the same time as the heat starts blasting Phoenix, the polar vortex — a system that usually keeps frigid air penned up near the North Pole — is forecast to send its chill deep into the Midwest ...

The weather forecast is looking promising for warmer weather as the calendar turns to March. In the East, a dramatic warm-up is in the forecast, and the Climate Prediction Center's outlook for March 6 ...