Al Roker explains how global warming impacts winter temperatures

ROKER: “Yesterday I heard you guys talking when we were talking about all this cold air and you said well if — if the planet’s warming how come it’s so cold. So we thought we would answer that for you. So Arctic air is contained by this polar vortex. It keeps it up there in the Arctic. However as the planet is warming climate change has actually caused significant warming up into the Arctic. So as that warm air comes up into the Arctic that weakens the polar vortex, that boundary, and it allows that cold air to move south, and that is why climate change, global planet warming actually allows some parts of the country to be colder than usual. For today that cold air goes all the way down to Texas. We’ve got snow showers, Great Lakes, some snow in the northern Rockies.”