Planning for the weather is an important factor for making your trip to Hailuogou a success, especially when you're splurging. The hottest months are usually July and August, with an average temperature of 11°C, while the coldest months are January and December, with an average of -3°C. The rainiest months in Hailuogou are July, August, June and May, with each month seeing an average of 344 mm of rainfall.