The island differs from other islands in its climate – the driest in Pribaikalye. It almost doesn’t rain: the amount of precipitation on Olkhon Island corresponds to that in semi-deserts – about 200 mm a year. This phenomenon is stipulated by the fact that air masses on their way to the island get over the Primorsky and Baikal Ridges and warmed coming down to the Baikal depression. Therefore, the relative humidity decreases and precipitation on the western coast of the lake and on the island is infrequent and short-time.
Winds are frequent guests of the island. These are winds mainly from the northwest, the most severe and subtle among which are Mountainous and Hurricane Sarma (variety of Mountainous). The arctic air passing through the Primorsky Ridge enters the valley tapering towards the Sarma River mouth which forms a natural aerodynamic tunnel at the entrance to Lake Baikal. Altitude difference is 500 m. Falling top-down masses of cold air gain high speed and destructive force bringing a lot of harm – they are able to overturn ships, uproot trees, and blow out roofs from houses. The wind with growing speed of up to 40-50 m/s is especially furious in autumn and winter and can rage for several days. Major catastrophes happened on Lake Baikal were caused by this wind. No matter how quick the wind Sarma grows, there are warning signs. Two-three hours before the first wind rush, black still clouds gather over the peaks of the Primorsky Ridge near the Sarminskoye gorge. Before the very beginning of the storm (15-30 minutes) a ray of light appears among the clouds and mountain peaks, as the local people say “the gate opens”. Usually winds blowing on the island are not unpleasant at all, especially when you are standing at the water and it is raining. They reach their maximum speed very rarely and usually in dead season.