Climate averages 1991–2020
Shūnan weather
in September.
A warm, wet month: the 3rd warmest and the joint 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Shūnan: daytime highs average 25.1°C and nights cool to about 19.0°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 169 mm of rain on roughly 12 days, which makes September a wet month (the joint 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 25 min on an average September day.
The nearest other city in this atlas is Hōfu (24 km away). In September its highs average 27.1°C, 2.0°C warmer than Shūnan, with 156 mm of rain.
Among the 303 cities listed in Japan, Shūnan ranks joint 216th of 303 for the warmest September highs and joint 76th of 303 for the driest September (rainfall, lowest first). The mean September high of those 303 cities is 25.7°C; Shūnan is 0.6°C cooler than that mean.
From September to October, average highs fall by 5.0°C to 20.1°C, and monthly rainfall falls from 169 mm to 113 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
Shūnan climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 6.6°C0.8°C | 0.8°C | 61 | 9.3 | 10.210 h |
| February | 7.8°C0.8°C | 0.8°C | 78 | 9.7 | 10.911 h |
| March | 11.3°C3.4°C | 3.4°C | 124 | 10.7 | 12.012 h |
| April | 16.2°C7.9°C | 7.9°C | 147 | 10.2 | 13.013 h |
| May | 20.5°C12.8°C | 12.8°C | 169 | 10.1 | 13.914 h |
| June | 23.6°C17.2°C | 17.2°C | 264 | 14.3 | 14.414 h |
| July | 27.1°C21.5°C | 21.5°C | 259 | 14.6 | 14.214 h |
| August | 28.3°C22.6°C | 22.6°C | 147 | 12.7 | 13.413 h |
| September, selected | 25.1°C19.0°C | 19.0°C | 169 | 11.5 | 12.412 h |
| October | 20.1°C13.4°C | 13.4°C | 113 | 7.7 | 11.411 h |
| November | 14.5°C8.0°C | 8.0°C | 78 | 8.1 | 10.410 h |
| December | 8.9°C3.0°C | 3.0°C | 69 | 9.8 | 9.910 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
- Hōfu in SeptemberJapan · 24 kmHigh 27.1°C · Low 20.7°C · 156 mm rain
- Yamaguchi in SeptemberJapan · 35 kmHigh 26.7°C · Low 19.6°C · 178 mm rain
- Iwakuni in SeptemberJapan · 37 kmHigh 26.5°C · Low 20.9°C · 185 mm rain
- Ube in SeptemberJapan · 55 kmHigh 26.4°C · Low 21.4°C · 161 mm rain
- Hatsukaichi in SeptemberJapan · 55 kmHigh 27.3°C · Low 20.5°C · 185 mm rain
- Hiroshima in SeptemberJapan · 67 kmHigh 26.9°C · Low 19.9°C · 188 mm rain
- Kure in SeptemberJapan · 70 kmHigh 25.5°C · Low 21.1°C · 163 mm rain
- Nakatsu in SeptemberJapan · 80 kmHigh 27.1°C · Low 21.1°C · 167 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 Shūnan) is explained once on the Shūnan year overview and on the Sources, method and limits page.