Sochi is a summer resort town with a warm, humid, subtropical climate. But the cold alpine climate of the Caucasus Mountains lies just a short distance inland. Nature helped the Olympic hosts in 2014 with cold weather and some natural snow during the weeks prior to the games.
The Caucasus Mountains form the border between Europe and Asia, spanning the gap between the Black Sea and the Caspian Sea. They also form the boundary between cold, dry air from Asia and humid air from the Mediterranean.
Flowing in from the south and west, the humid ocean air hits the Caucasus and gets pushed up. The rising air cools, resulting in heavy snowfall when temperatures are cool enough.
Because of this pattern, snowfall tends to be heaviest in the southern and western Caucasus. Rosa Khutor, the new ski resort that is the venue for mountain events at these Olympics, is built in one such region.
Image courtesy of NASA.