Other facts from our historical weather data: Which months have the greatest rainfall in Ban Rai? Most rainfall (rainy season) is seen in May, July, August, September and October. Does Ban Rai have a dry season? Yes, the months of January, February and December are very dry. Which is the hottest month in Ban Rai? April has an average maximum temperature of 37°C (99°F) and is the hottest month of the year. Which is the coolest month in Ban Rai? The coolest month is January with an average maximum temperature of 30°C (86°F). Which is the wettest month in Ban Rai? September tops the wettest month list with 255mm (10 in) of rainfall. Which is the driest month in Ban Rai? December is the driest month with 11mm (0.4 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.