Snow and winds are likely to trigger flight cancellations and cause headaches for people traveling to DC for Inauguration Day.

The polar vortex is expected to reach the Utah-Idaho border sometime in the late afternoon and evening Friday as it continues to move south. As it moves through parts of the state, it will produce small snow showers, bringing more snow to the region before drier conditions return.

A blast of Arctic air is set to cover much of the United States with temperatures below freezing starting on Friday and into next week, impacting millions of Americans in nearly all of the contiguous states.

Dangerous temperatures are sweeping the country, with 100 million people from the Plains to the Northeast feeling the chill. Even those in the South will see some effects. Several cities have already declared weather emergencies,

These severe cold events occur when the polar jet stream – the familiar jet stream of winter that runs along the boundary between Arctic and more temperate air – dips deeply southward, bringing the cold Arctic air to regions that don’t often experience it.

The 10 Weather Impact team issued Alert Days for next week because of the polar vortex being responsible for the cold temperatures.

A major cold blast is in store for millions of Americans as a lobe of a polar vortex will bring brutally cold temperatures to nearly every American east of the Rockies.

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.

Very cold arctic air will interact with several systems to bring chances of freezing rain, sleet, and snow

With a composite score of 88, the most dangerous car for winter driving was found to be the Chevrolet Silverado 1500. The model was involved in the highest number of fatal winter crashes over a one-year period with 127 fatal crashes per 100,000 units sold.

State Climatologist Jay Grymes said there could be lows of 20 degrees across the state between Monday and Wednesday and the National Weather Service (NWS) has said Baton Rouge could see its first snowfall in seven years. Newsweek has contacted the Louisiana Governor's Office of Homeland Security and Emergency Preparedness for comment.