In Video: Arctic blast to drop temperatures for millions of Americans

Temperature Plunges Across the Country: Millions Under Frost and Freeze Alerts

A brutal cold front is sweeping across the nation, bringing with it a blast of Arctic air that will leave millions under frost and freeze alerts. A low-pressure system is moving through the Midwest, bringing strong rain and hail to parts of Tennessee, reducing visibility. NBC News Meteorologist Bill Karins reports on the severe storms and the impending cold outbreak.

Severe Weather Developments

A tornado watch was issued for areas of Tennessee, but so far, no tornadoes have been reported. However, strong thunderstorms have been seen in the region, with the possibility of hail and high winds.

Understanding the Polar Vortex

The cold air is a result of a breakaway piece of the Polar Vortex, a atmospheric phenomenon that typically holds cold air in place over the North Pole. The weaker-than-normal polar vortex has allowed this piece of cold air to break off and make its way south.

Frigid Temperatures Ahead

By Monday night and Tuesday morning, the cold air will have reached the Gulf Coast, bringing temperatures down into the 20s and 30s. Wind chills will make it feel even colder, with some areas experiencing single-digit temperatures.

Snowfall Expected in Certain Regions

A swath of heavy snow will fall near the Great Lakes, with areas off Lake Michigan, Lake Erie, and Lake Ontario expected to see the most significant accumulation. Northern New York, Vermont, and areas as far south as parts of the Midwest will see snowfall.

Florida Braces for Unseasonable Cold

Even in central Florida, the wind chill feel like temperature will be in the 30s, unseasonably cold for the typically mild region.

Timing of the Cold Front

Monday will see temperatures slightly improved, but Tuesday night will bring the coldest conditions, with temperatures plummeting below freezing.

Action to Take

Homeowners are advised to act quickly to prepare for the cold weather, including raking leaves before the snow arrives and ensuring central heating systems are functioning properly.