Visiting local bars in Toga Onsen is more fun in good weather. These rainfall averages and temperatures can help you choose the best time for bar hopping. The hottest months are usually August and July with an average temp of 71°F, while the coldest months are February and January with an average of 36°F. The rainiest months in Toga Onsen are August, July, October, and September, with each month seeing an average of 9 inches of rainfall.