The large-scale environment of the European 2012 high-impact cold wave: prolonged upstream and downstream atmospheric blocking

Abstract

In January/February 2012, eastern Europe experienced persistent cold temperatures and snowstorms. The occurrence of a cold wave is not unusual in this region, but this period was remarkable for its duration and intensity. It was associated with (i) an eastern Atlantic ridge with a northeastward extension that intensified the northwest–southeast-tilted trough to create favourable conditions for cold-air outbreaks and snowstorms; (ii) a Siberian high which helped to make the cold wave stationary. The juxtaposition of these flow patterns promoted the occurrence of persistent cold temperatures and snow. Results from this analysis indicate that the atmospheric blocking was likely to be responsible for establishing and maintaining the cold conditions.