Other facts from our historical weather data: Which is the warmest month in Bowness-on-Windermere? July has an average maximum temperature of 19°C (66°F) and is the warmest month of the year. Which is the coldest month in Bowness-on-Windermere? The coldest month is February with an average maximum temperature of 7°C (45°F). Which is the wettest month in Bowness-on-Windermere? December tops the wettest month list with 161mm (6.3 in) of rainfall. Which is the driest month in Bowness-on-Windermere? April is the driest month with 89mm (3.5 in) of precipitation. Which is the sunniest month in Bowness-on-Windermere? May is the sunniest month with an average of 217 hours of sunshine. 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.