Nagano weather in September
Temperature, rain and sunshine in September: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in September
Fair
Best time to visit: May – June, October
What is the weather like in Nagano in September?
In September, Nagano is warm: daytime highs average 25 °C, and nights cool down to about 17 °C. Expect around 5 hours of sunshine a day. It rains often – on about 18 days, adding up to 206 mm. All in all, September is a so-so month for a holiday in Nagano.
September compared
How the weather changes from August to October. Tap a month to open it.
| AugustAug | SeptemberSep | OctoberOct | |
|---|---|---|---|
| Score | 50 | 58 | 60 |
| Day | 29° | 25° | 19° |
| Night | 21° | 17° | 10° |
| Sun | 7 h | 5 h | 5 h |
| Rain days | 21 | 18 | 17 |
More details for September
- Daylight
- 12 h 28 min05:28 – 17:57
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 10 daysdew point 18 °C or moreAll months
- Wind
- 10 km/haverage daily peakAll months
- Cloud cover
- 72 %on averageAll months
- Hot days
- 2 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snowAll months
- Time zone
- UTC+9Asia/Tokyo
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %33 %
- Few rainy daysweight 30 %4 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in September
- Sunscreen
- Sunglasses & sun hat
- Rain jacket or umbrella
Nagano in September: quick answers
Is Nagano hot in September?
Warm rather than hot: in September, daytime highs in Nagano average 25 °C and nights cool to about 17 °C. On about 2 days the thermometer climbs to 30 °C or more.
Does it rain much in Nagano in September?
It rains often – on about 18 days, adding up to 206 mm.
Nagano month by month
The whole year in NaganoAll destinations: JapanWhere to go in September
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences