Planning for the weather is a good way to make your trip to Bosteri relaxing and enjoyable, especially when you’re splurging. The hottest months are usually July and August with an average temp of 57°F, while the coldest months are January and February with an average of 29°F. The snowiest months in Bosteri are March, February, December, and January, with each month seeing an average of 37 inches of snowfall.