Planning for the weather is a good way to make your trip to Kottayam relaxing and enjoyable, especially when you're splurging. The hottest months are usually March and February, with an average temperature of 28°C, while the coldest months are January and December, with an average of 26°C. The rainiest months in Kottayam are June, July, August and May, with each month seeing an average of 461 mm of rainfall.