Other facts from our historical weather data: Which months have the greatest rainfall in Chengalpattu? Most rainfall (rainy season) is seen in October and November. Does Chengalpattu have a dry season? Yes, the months of January, February and March are very dry. Which is the hottest month in Chengalpattu? May has an average maximum temperature of 37°C (99°F) and is the hottest month of the year. Which is the coolest month in Chengalpattu? The coolest month is January with an average maximum temperature of 29°C (84°F). Which is the wettest month in Chengalpattu? October tops the wettest month list with 208mm (8.2 in) of rainfall. Which is the driest month in Chengalpattu? February is the driest month with 11mm (0.4 in) of precipitation. Which is the sunniest month in Chengalpattu? May is the sunniest month with an average of 301 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.