The temperatures in Yamanashi in September are comfortable with low of 15°C and and high up to 23°C.
You can expect rain for roughly half of the month of September in Yamanashi. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Yamanashi in September 2025.
If you’re planning to visit Yamanashi in the near future, we highly recommend that you review the 14 day weather forecast for Yamanashi before you arrive.
Temperatures
23° / 15°
Rainy Days
11
Snowy Days
0
Dry Days
19
Rainfall
109
mm
Sun Hours
1.4
Hrs
