If you’re looking forward to lots of outings with your partner, check out these details about year-round temperatures in Jachymov: The hottest months are usually August and July with an average temp of 57°F, while the coldest months are February and January with an average of 29°F. The snowiest months in Jachymov are December, November, January, and February, with each month seeing an average of 13 inches of snowfall.