Other facts from our historical weather data: Which is the warmest month in Ust'-Bol'sheretsk? August has an average maximum temperature of 16°C (61°F) and is the warmest month of the year. Which is the coldest month in Ust'-Bol'sheretsk? The coldest month is January with an average maximum temperature of -4°C (25°F). Which is the wettest month in Ust'-Bol'sheretsk? October tops the wettest month list with 146mm (5.7 in) of rainfall. Which is the driest month in Ust'-Bol'sheretsk? January is the driest month with 49mm (1.9 in) of precipitation. No idea where to travel to this year? We have a tool that recommends destinations based on your ideal conditions. Find out where to go with our weather planner.