The weather in Nagasaki in September is very hot. The average temperatures are between 23°C and 27°C, drinking water regularly is advisable.
You can expect rain for roughly half of the month of September in Nagasaki. 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 Nagasaki in September 2025.
If you’re planning to visit Nagasaki in the near future, we highly recommend that you review the 14 day weather forecast for Nagasaki before you arrive.
Temperatures
27° / 23°
Rainy Days
10
Snowy Days
0
Dry Days
20
Rainfall
313
mm
Sun Hours
10.2
Hrs
