On a recent Saturday, while much of Japan sweltered under punishing heat and humidity, groups of hikers were savoring the crisp mountain air on an off-peak ski slope in Hakuba, Nagano Prefecture.

In the Kurobishidaira area at an altitude of 1,680 meters, staff at a restaurant with a panoramic view of the mountain valley were busy serving meals and drinks to adventure-seeking customers.

Overall, though, the Hakuba Happo-One ski resort was relatively quiet, with many lifts empty — after all, Hakuba is far better known for its powder snow than its cool breezes.