The East Coast of the USA should start bracing itself for a cold spell after meteorologists confirmed that the polar vortex has split into three parts. The change is likely to result in plummeting temperatures for much of the eastern United States.
So far, much of the eastern U.S. has enjoyed a relatively mild winter. But that is all set to change with arctic temperatures likely to reach as far south as Nashville, according to the Washington Post.
The polar vortex is an atmospheric circulation pattern that usually sits above the poles, in a layer of the atmosphere known as the stratosphere. It can weaken when temperatures at the poles become warmer and on occasion, this causes it to break up into smaller "sister vortices" that can travel great distances from the poles. These "sister vortices" typically bring with them stormy weather and extremely low temperatures.
As Dr. Judah Cohen of Atmospheric and Environmental Research (AER) explained to the Post, "A sudden stratospheric warming usually leads to a warm Arctic not only in the stratosphere but also at the surface as well. And a warmer Arctic favors more severe winter weather in the NH mid-latitudes including the Eastern U.S. For the northeastern U.S., this could mean disruptive snowstorms."
Its effect could be felt as soon as the next few days. The Post reports that this winter has been among the top 10 warmest on record in places like Minneapolis and Milwaukee. But in the second half of this month, high temperatures in the northern Plains and upper Midwest are predicted to only reach single digits. When the wind chill is factored in as well, it is going to feel like single digit temperatures across much of the eastern United States.
In some places, it will be even worse. In Minneapolis, the forecast low temperature for this Saturday is a chilly -7 degrees F. Fargo, North Dakota, will see temperatures fall even lower this weekend. The high on Saturday there will be -4 degrees, while the low will reach down to -20.
On Sunday, the attention of much of the U.S. will be on Kansas City, which is hosting the AFC Championship game between the Kansas City Chiefs and the New England Patriots. NFL fans needn't worry about temperatures dipping as low as in Fargo. With the forecast of a high temperature that day of just 15 degrees, it is still going to be very cool and those lucky enough to have tickets to the game are advised to wrap up warm.