Alberta Clipper is the name given to a low pressure weather system that actually starts in the Gulf of Alaska area and continues eastward over the Rocky Mountains. The clippers continue developing east of the Rockies and then blow quickly from Alberta into the States, across the Great Plains and on toward the East coast. They are not frequently accompanied by a lot of snow but they do bring lots of freezing cold air. Lake effect snow can be expected where cold dry air moves rapidly across warm lake waters. The strong winds then take the white stuff farther inland. For the most part Alberta Clippers bring lots of cold cold air.
Source:USA Today Weather. The Alberta Clipper (http://www.usatoday.com/weather/wclipper.htm)