Weather in Nagasaki: September
| Average day temperature: | 82.9°F | |
| Average night temperature: | 74.8°F | |
| Sea water temperature: | 80.3°F | |
| Number of sunny days: | 11 days | |
| Day length: | 11.9 - 12.8 hours | |
| Number of rainy days: | 8 days | |
| Precipitation totals: | 6.2 in. | |
| more information | ||
forecast
| Nagasaki |
temperature
| Nagasaki |
Air temperature in September, °F
The highest day temperature during September of 2025 was 87°F. At the same time the lowest night temperature was 71°F. Daily and nightly averages during September were 83.0°F and 77.7°F.
Sea water temperature in Nagasaki in September, °F
The average sea water temperature in September of 2025 was 83.9°F. The highest and lowest sea temperatures during the month were 85.3°F and 81.9°F.
Number of sunny, partly cloudy and cloudy days in September is almost equal.
Precipitation total in September, in.
Precipitation total value in Nagasaki in September is 6.6 in.
The average wind speed value in September is 7.6 mph It makes September one of the least windy months of the year.
This chart shows average number of hours during the day when sunlight can reach the ground. It depends on day length and cloudiness during the day. The average number of sunny hours in September is: 7.0.
Best time for vacation in Nagasaki
Nagasaki on a weather map

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