Yamanashi Weather & Climate Guide 2026

Yamanashi Prefecture is a landlocked prefecture in the Chubu region of central Honshu, cradled in the Kofu Basin and ringed by mountains, most famously the northern slopes of Mount Fuji and the Fuji Five Lakes. Home to the Yoshida Trail, the most-used of Mount Fuji's four climbing routes, and to Japan's oldest and largest wine region around Katsunuma, Yamanashi pairs alpine and lakeside scenery with a proud viticulture and fruit-growing tradition, plus the jewelry and crystal-carving craftsmanship of its capital, Kofu City.

Yamanashi is a landlocked, mountain-ringed prefecture west of Tokyo, split between the low, enclosed Kofu Basin and the higher Fuji Five Lakes region at the northern foot of Mount Fuji. The basin has a pronounced inland climate: summers are hot and humid, sometimes among the hottest recorded anywhere in Japan, while winters are cold, dry, and sunny with far less snow than Japan's Sea of Japan coast. The Fuji Five Lakes area, sitting roughly 800–1,000m higher, is noticeably cooler year-round and sees more frequent snow. Mount Fuji itself creates its own localized weather, with the summit under snow most of the year and cloud cover often obscuring the peak even on days that are clear at lake level.