If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Velky Slavkov: The hottest months are usually August and July with an average temp of 59°F, while the coldest months are January and February with an average of 27°F. The snowiest months in Velky Slavkov are December, January, November, and April, with each month seeing an average of 15 inches of snowfall.