Other facts from our historical weather data: Which months have the greatest rainfall in Passy? Most rainfall (rainy season) is seen in January, May, June, July and December. When is winter in Passy? The coldest season / winter is in the following months: January, February and December. Which is the warmest month in Passy? 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 Passy? The coldest month is January with an average maximum temperature of -1°C (30°F). Which is the wettest month in Passy? December tops the wettest month list with 178mm (7 in) of rainfall. Which is the driest month in Passy? October is the driest month with 125mm (4.9 in) of precipitation. Which is the sunniest month in Passy? July is the sunniest month with an average of 275 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.