GREAT LAKES, Mich. -- The comma-shaped cloud seen over the Great Lakes is a low pressure center known as the Polar Vortex.
The low center typically sits over the Arctic region during the winter months and migrates west to east. The upper low is the cold core of the frigid air, pushing freezing temperatures south to the Gulf Of Mexico.
The photo above is courtesy of NOAA, whose meteorologists explained that a high pressure system parked over Greenland and Canada is responsible for displacing Arctic air southward. Some meteorologists believe changing weather patterns will have a tendency to drive Arctic air farther south into the United States than we have seen over recent decades.
Climate meteorologists will be tracking extreme cold outbreaks in the coming years to see if cold episodes occur more often than historical weather trends of the past.
Such large reaching and long lasting cold outbreaks across the eastern United States would more often than not correlate directly to below normal precipitation here in the Northwest.
The cold air develops an upper level trough of low pressure, which is often associated with a dry ridge of high pressure across the west.
Meteorologist Rod Hill, follow me @