It's only November, and half the U.S. is blanketed in snow—six feet deep and counting in and around Buffalo, New York—while parts of the Deep South have been waking up to temperatures that are just above freezing.

Temperatures are expected to remain well below normal from the Great Plains to the eastern seaboard over the next few days, while snow will likely continue downwind of the Great Lakes, according to the National Weather Service.

What's going on? Blame the so-called lake effect, the polar vortex, a kink in the jet stream—and an old super typhoon.

The lake-effect snow comes from west-southwesterly winds of a storm aligning neatly with the lengths of Lakes Erie and Ontario, which sit between the American Midwest