Other facts from our historical weather data: Which months have the greatest rainfall in Flachau? Most rainfall (rainy season) is seen in May, June, July, August and September. When is winter in Flachau? The coldest season / winter is in the following months: January, February and December. Which is the warmest month in Flachau? August has an average maximum temperature of 20°C (68°F) and is the warmest month of the year. Which is the coldest month in Flachau? The coldest month is January with an average maximum temperature of -1°C (30°F). Which is the wettest month in Flachau? June tops the wettest month list with 190mm (7.5 in) of rainfall. Which is the driest month in Flachau? January is the driest month with 99mm (3.9 in) of precipitation. Which is the sunniest month in Flachau? July is the sunniest month with an average of 196 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.