CANADIAN HIGH

also called Alaskan high large atmospheric high-pressure centre produced by the extremely low winter temperatures over northwestern Canada. Its cold, dense air does not extend above 3 km (2 miles). The high's location east of the Canadian Rockies shelters it from the relatively warm Pacific Ocean and helps it maintain its identity. Its average January sea level pressure is 1,020 millibars (30.12 inches of mercury). The Canadian high gradually shifts southeastward until it eventually reaches the Atlantic Ocean, where it merges with the Azores high.