In the past week, the phrase 'polar vortex' has been thrown around a lot.  While it's fun to say, the physical reality of this kind of air mass can be dangerous.  Get ready for your science lesson class, because the polar vortex is arriving.

According to the NASA Earth Observatory, polar vortexes are nothing new. They happen seasonally at the North Pole.  The formation of a polar vortex resembles a hurricane when fast-moving, mostly warm winds build up around a calm center. But unlike a hurricane, these winds are frigid, circling the Arctic at more than 100 mph.

These winds are traditionally trapped in the Arctic. But once a polar vortex weakens or splits apart, these cold wind patterns are flung into our backyards.  Scientists believe warming temperatures in the Arctic may be responsible for the weakening of the polar vortex, setting off a chain of events that forces the air into our winter weather systems.

Here's a NASA illustration of the polar vortex (left) and it splitting in two (right):

 

courtesy of NASA

The weather we're experiencing in South Jersey tonight and tomorrow is actually Arctic air invading from the north.