Planning for the weather is an important factor for making your trip to Kostanay a success, especially when you're splurging. The hottest months are usually July and August with an average temp of 66°F, while the coldest months are January and February with an average of 11°F. The snowiest months in Kostanay are January, March, February, and December, with each month seeing an average of 63 inches of snowfall.