Climate averages 1991–2020
Nagaoka weather
in September.
A warm, wet month: the 3rd warmest and the 7th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Nagaoka: daytime highs average 25.6°C and nights cool to about 17.7°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 144 mm of rain on roughly 14 days, which makes September a wet month (the 7th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 28 min on an average September day.
The nearest other city in this atlas is Sanjō (21 km away). In September its highs average 25.4°C, about as warm as Nagaoka, with 156 mm of rain.
Among the 303 cities listed in Japan, Nagaoka ranks joint 188th of 303 for the warmest September highs and joint 16th of 303 for the driest September (rainfall, lowest first). The mean September high of those 303 cities is 25.7°C; Nagaoka is 0.1°C cooler than that mean.
From September to October, average highs fall by 6.1°C to 19.5°C, and monthly rainfall falls from 144 mm to 143 mm.
The annual picture
September in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Nagaoka climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 3.8°C-2.5°C | -2.5°C | 179 | 25.1 | 9.910 h |
| February | 4.5°C-2.7°C | -2.7°C | 127 | 20.6 | 10.811 h |
| March | 8.9°C-0.4°C | -0.4°C | 126 | 19.6 | 11.912 h |
| April | 15.7°C4.8°C | 4.8°C | 94 | 14.3 | 13.113 h |
| May | 21.4°C10.6°C | 10.6°C | 94 | 11.9 | 14.214 h |
| June | 25.1°C15.7°C | 15.7°C | 115 | 12.5 | 14.715 h |
| July | 28.1°C20.4°C | 20.4°C | 207 | 16.1 | 14.514 h |
| August | 29.8°C21.6°C | 21.6°C | 146 | 14.1 | 13.614 h |
| September, selected | 25.6°C17.7°C | 17.7°C | 144 | 14.0 | 12.512 h |
| October | 19.5°C11.3°C | 11.3°C | 143 | 14.8 | 11.311 h |
| November | 13.3°C5.3°C | 5.3°C | 145 | 18.2 | 10.210 h |
| December | 7.0°C0.2°C | 0.2°C | 181 | 23.7 | 9.610 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
September in nearby cities
- Sanjō in SeptemberJapan · 21 kmHigh 25.4°C · Low 17.9°C · 156 mm rain
- Tsubame in SeptemberJapan · 25 kmHigh 25.0°C · Low 18.6°C · 139 mm rain
- Kashiwazaki in SeptemberJapan · 28 kmHigh 25.4°C · Low 18.2°C · 163 mm rain
- Niigata in SeptemberJapan · 55 kmHigh 24.7°C · Low 19.2°C · 146 mm rain
- Jōetsu in SeptemberJapan · 64 kmHigh 25.2°C · Low 18.4°C · 162 mm rain
- Shibata in SeptemberJapan · 70 kmHigh 24.8°C · Low 17.8°C · 160 mm rain
- Aizu-Wakamatsu in SeptemberJapan · 97 kmHigh 23.5°C · Low 16.9°C · 144 mm rain
- Nikkō in SeptemberJapan · 103 kmHigh 22.8°C · Low 16.3°C · 268 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Nagaoka) is explained once on the Nagaoka year overview and on the Sources, method and limits page.