If you’re hoping to get lost in the rain on your romantic getaway, take a look at these details about year-round temperatures in Nagaon: The hottest months are usually May and August, with an average temperature of 27°C, while the coldest months are January and December, with an average of 20°C. The rainiest months in Nagaon are July, August, June and September, with each month seeing an average of 524 mm of rainfall.