Even if you are going to relax on Lake Baikal in the middle of summer, be sure to bring a warm sweater or jacket with you. Most often it is sunny and hot during the day at this time of the year. You will sunbathe and swim. But the nights can be very cold. The climate of Eastern Siberia is sharply continental, and its peculiarity is sharp temperature fluctuations. After a 30-degree heat wave, a bitterly cold twilight may come in the afternoon.
In the off-season and in winter, thermal underwear will not hurt. However, remember that even in the middle of winter there are no severe frosts on Lake Baikal, this contributes to the special microclimate of the lake.
June is a great time to relax on Lake Baikal. It's getting warm, but there's no heat. The temperature on Lake Baikal fluctuates around 15 degrees, while in Irkutsk and Ulan-Ude it may already be under 30 C. There are few tourists on Lake Baikal in June – it is not clear why vacationers prefer July and August to this wonderful month. If beach holidays were developed on Lake Baikal, it would seem logical, but it is rarely possible to swim on Lake Baikal, even in July and August – the water is too cold for this.
The water warms up to 15-18 degrees in the summer months, in some bays it reaches 20-22. To put it mildly, this temperature is not enough for bathing. Baikal is beautiful at any time of the year, so June is a great month to plan your vacation. Do not forget to bring warm clothes to make your stay especially pleasant.