If you're looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Yuzhno-Sakhalinsk: The hottest months are usually August and July, with an average temperature of 15°C, while the coldest months are February and January, with an average of -9°C. The snowiest months in Yuzhno-Sakhalinsk are March, January, February and December, with each month seeing an average of 249 cm of snowfall.