Taking into account the local weather in Casper is an important factor for planning your visit, especially if you plan to spend your trip poolside. The hottest months are usually July and August with an average temp of 68°F, while the coldest months are February and January with an average of 23°F. The snowiest months in Casper are November, February, January, and April, with each month seeing an average of 8 inches of snowfall.