The proper term is actually "Blue Norther" (without the final "n") and yes, it's a cold front that comes down from the North Pole and blows across the great plains. Temperatures have been recorded to drop 60 degrees or more in a matter of a few hours when a true Blue Norther starts blowing.
BLUE NORTHER
Refers to a swift-moving
cold frontal passage in the southern Great Plains, marked by a dark, blue-black sky with strong
wintery winds from the northwest or north and
temperatures that may drop 20°F to 30°F in a few minutes.