An area stretching from Texas to Tennessee braced Wednesday for the possible arrival of freezing rain and snow even as some parts of the U.S. hit by the plunging polar vortex this week began to shake off its icy effects.

However, a deep freeze, thanks to the polar vortex dipping down from Siberia, is about to bring even harsher, frigid temperatures to nearly 300 million Americans starting this weekend.The polar vortex is a large area of cold air and low pressure that normally spins over the North and South Poles.