Snow and winds are likely to disrupt traffic, trigger flight cancellations, and cause headaches for people traveling to D.C. for Inauguration Day. Baby, it’s cold outside, and it’s about to get even colder for much of the United States.

A polar vortex is slated to sweep most of the continental US bringing winter storm warnings and a hazardous freeze to millions.

The polar vortex is a ring of cold air that typically circles the Arctic. A strong jet stream essentially acts like a fence, keeping it locked there. If there's any weakening in the jet stream (the fence), the frigid air can become unstable and spill out. This sends the normally trapped cold air much farther south.

The most unusually cold air in the Northern Hemisphere will be over the United States early next week, bringing dangerously frigid conditions.

A polar vortex is currently hitting the United States, with schools closed in many areas and at least four deaths caused by treacherous conditions.

A lobe of the polar vortex, a stormy ring that typically keeps the coldest air locked up near the North Pole, will dip southward into the United States this weekend into next week. Polar air ...

Despite a cold start to the day, most of the U.S. will experience seasonably mild temperatures on Thursday. However, dangerous changes are on the way as a polar vortex tightens its grip on the nation as sends temperatures tumbling below freezing starting this weekend.

Americans were bracing Thursday for frigid temperatures that forecasters said could produce life-threatening conditions, with Donald Trump's inauguration expected to be the coldest in 40 years.

What is the polar vortex? How it’s responsible for dangerous cold Ronald Reagan had both the warmest and the coldest January inaugurations on record. Reagan began his first term in office in 1981 with a temperature of 12.

US President-Elect Donald Trump’s supporters braved the icy polar vortex on Saturday (local time) to catch a glimpse of the inaugural events leading up to his swearing-in ceremony. Several supporters were seen filming the fireworks that took place at Trump National Golf Club and wearing “Make America Great Again” (MAGA)

A dangerous and potentially life-threatening stretch of cold weather has much of the U.S. on alert as a lobe of the polar vortex invades the nation and sends temperatures tumbling to levels not seen in years.