Polar Vortex in the Forecast Again

Meteorologists have blamed a phenomenon called the polar vortex for the bitter cold that has descended on much of the central and eastern United States in last week of January.

What is Polar Vortex?

• There are not one but two polar vortexes in each hemisphere, North and South.
• One exists in the lowest layer of the atmosphere, the troposphere, which is where we live and where the weather happens.
• The other exists in the second-lowest, called the stratosphere, which is a shroud of thin air that gets warmer at higher altitudes.
• If the two polar vortexes line up just right, the Lower ....