An extreme weather pattern is affecting conditions across the U.S. and Europe, specifically a powerful area of high pressure across Greenland and Hudson Bay. This feature, known as a “Greenland Block,” along with another weather cycle, typically lead to cold and snow in the eastern U.S., parts of Europe and Asia.
The big picture: The blocking high over Greenland is acting like an atmospheric detour, diverting weather systems around it and favoring, but not guaranteeing, cold air outbreaks in Europe and North America as Christmas approaches.
