Planning for the weather is a good way to make your trip to Manapouri relaxing and enjoyable, especially when you're splurging. The hottest months are usually January and February, with an average temperature of 9°C, while the coldest months are July and August, with an average of 2°C. The rainiest months in Manapouri are October, September, May and January, with each month seeing an average of 346 mm of rainfall.