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The Blue Norther
11/20/2002
Listen in RealAudio 
Hi, I'm Bryan Yeaton and this is The Weather Notebook. Today on the show we look at cold
fronts that are really cold fronts. Some of the most dramatic fronts on earth surge across the
North American prairie each winter. The cold winds associated with these fronts are called
Blue Northers in Texas, but their stomping ground ranges from Alberta to the Gulf
Coast.
Blue Northers get their start when a bitterly cold air mass builds up not far from the North
Pole, usually beneath a dome of high pressure. This leads to light winds, clear skies, and
successively colder nights. Sometimes the high pressure builds up enough to spread south, like
a blob of cold maple syrup rolling across your pancakes. However, for a really intense
Norther, you need the jet stream to help push the air south. When everything comes together, a
newborn cold front can race south at speeds of more than 40 miles per hour, quick enough to go
from Canada to the Gulf of Mexico in under two days.
A Blue Norther arrives with howling winds that can push up a thick blanket of stratus clouds.
These can look bluish-gray as they approach, thus the colorful name. One classic Blue Norther
hit the plains in November of 1911. Just hours after the front passed, temperatures in
Oklahoma City dropped from a balmy record high of 83 Fahrenheit or 28 C, to a record low of
17, that's minus eight Celsius. Both readings still stand as testimony to what can happen when
the wind comes sweeping down the plain.
The Weather Notebook is made possible by a grant from The National Science Foundation.
Additional support comes from Subaru of America, The Beauty of All-Wheel Drive. Thanks today
to Executive Producer Peter Crane.
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