[ninty]

well it was named after the chinook indian people, but basically it has to do with the winds and how they come over the mountains. high and low pressure and all that jazz and basically bring in warm air and pushes the arctic air back north.

I think in southern alberta and chile are the only places in the world where it happens.

If you look at the clouds during a chinook, you'll see the chinook arch which is actually pretty amazing. You'll see a wall of clouds that just suddenly stops in a straight line. half of the sky is cloud, the other half is perfectly clear.

kinda like this but this isn't a very good view:

http://content.answers.com/main/content ... rch-01.jpg