ALBERTACLIPPER
Alberta clipper
A clipper originates when warm, moist winds from the Pacific Ocean come into contact with the mountains in the provinces of British Columbia and then Alberta. The air travels down the lee side of the mountains, often forming a chinook in Alberta, then develops into a storm over the Canadian prairies when it becomes entangled with the cold air mass that normally occupies the region in winter. The storm then slides southward and gets caught up in the jet stream, sending the storm barreling into central and eastern areas of North America.The above text is a snippet from Wikipedia: Alberta clipper
and as such is available under the Creative Commons Attribution/Share-Alike License.