Other facts from our historical weather data: Does Rossland have a dry season? Yes, the months of July and August are very dry. When is winter in Rossland? The coldest season / winter is in the following months: January, February, November and December. Which is the warmest month in Rossland? July has an average maximum temperature of 15°C (59°F) and is the warmest month of the year. Which is the coldest month in Rossland? The coldest month is December with an average maximum temperature of -1°C (30°F). Which is the wettest month in Rossland? November tops the wettest month list with 62mm (2.4 in) of rainfall. Which is the driest month in Rossland? August is the driest month with 14mm (0.6 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.