The temperatures in Nagano in August are comfortable with low of 18°C and and high up to 29°C.
There’s going to be many days of rain during the month of August in Nagano.
Nagano should expect an average of 15 to 22 days of rain, so be sure to bring along a waterproof jacket to stay dry this month!
Our weather forecast can give you a great sense of what weather to expect in Nagano in August 2025.
If you’re planning to visit Nagano in the near future, we highly recommend that you review the 14 day weather forecast for Nagano before you arrive.
Temperatures
29° / 18°
Rainy Days
15
Snowy Days
0
Dry Days
16
Rainfall
83
mm
Sun Hours
1.7
Hrs
