The foothills and mountainous areas (including the Greater Caucasus Mountains) experience cool, wet summers and snowy winters, with snow cover often exceeding two meters in many regions. The penetration of humid air masses from the Black Sea to the west of South Ossetia is often blocked by the Likhi mountain range. The wettest periods of the year in South Ossetia generally occur during spring and autumn while the winter and summer months tend to be the driest. Elevation plays an important role in South Ossetia where climatic conditions above  are considerably colder than in any lower-lying areas. The regions that lie above  frequently experience frost even during the summer months.