Great Britain is usually exempt from the cold winter weather in other countries of the same latitude. (Warm air from the Gulf Stream keeps temperatures mild; read more here.) However, as the image above shows, Britain's winter was much colder than usual. One reason for this change is The Arctic Oscillation, the process of alternating pressure regions in the northern hemisphere. For more on Britain's recent and upcoming weather, check out this article from the Guardian discussing El Nino.