The annual precipitation is 600-700 mm in the lower altitude zones and 1000-1200 mm in the higher ones. The rainfall occurs mostly in winter and spring, while summer is driest season. The air humidity is 60-75% in August and 80-85 % in December. In winter the precipitation is mainly snow, varying from 70-90% at the lower altitudes to 100% at higher. The average number of days with snow cover varies from 20-30 to 120-160. The highest thickness of the snow cover reaches 40-60 cm at 1000-1800 m in February and 160-180 cm above 1800 m in March (190 cm on Vihren). In some winters the snow thickness can reach 250-350 cm. Avalanches occur frequently in winter.