Weather will likely play an important role when you plan your trip to Namchi, and keep in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually June and August with an average temp of 73°F, while the coldest months are January and December with an average of 57°F. The rainiest months in Namchi are July, August, June, and September, with each month seeing an average of 34 inches of rainfall.