It's that time of year that cold blasts become the norm for many of us. 

The temperature difference between the equator and the North Pole is greatest during the winter months.

This is because the North Pole sits in complete darkness, allowing cold air to become dense, whereas the equator maintains a constant temperature year-round.

The entire purpose of weather on this planet is to create a balance in temperature, and this is what storms are for.

Storms transport cold air from the poles southward and move warm air from the equator towards the poles. Of course, the temperature never equals out, hence why we will always have weather.

Mid-latitude storms, along with the jet stream, are stronger in the winter compared to the summer. When a storm forms, an Arctic blast can invade the U.S with crippling cold, reaching areas as far south as the Gulf Coast. 

Watch the video above to see where the cold air comes from and how it can stay so bitterly cold in much of the U.S.