When “polar vortex” appears in the news, it can refer to one of two different, but related, weather patterns.

Extreme heat warnings stretched from Windsor to Timmins; humidex values climbed to the mid-40s. In Toronto, panic over ...

Charlottesville and much of central Virginia were under an extreme heat warning Tuesday, with temperatures predicted to stay ...

A new study challenges the idea that climate change is behind the erratic wintertime behavior of the polar jet stream, the ...