Climate averages 1991–2020
Kōnosu weather
in September.
A warm, very wet month: the 3rd warmest and the 11th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
September is a warm month in Kōnosu: daytime highs average 25.9°C and nights cool to about 19.2°C. By daytime temperature it is the 3rd warmest of the 12 months.
Expect about 186 mm of rain on roughly 14 days, which makes September a very wet month (the 11th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 27 min on an average September day.
The nearest other city in this atlas is Kazo (9 km away). In September its highs average 26.1°C, about as warm as Kōnosu, with 186 mm of rain.
Among the 303 cities listed in Japan, Kōnosu ranks joint 168th of 303 for the warmest September highs and joint 142nd of 303 for the driest September (rainfall, lowest first). The mean September high of those 303 cities is 25.7°C; Kōnosu is 0.2°C warmer than that mean.
From September to October, average highs fall by 5.5°C to 20.4°C, and monthly rainfall rises from 186 mm to 196 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
Kōnosu climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 7.8°C-1.9°C | -1.9°C | 57 | 6.0 | 10.010 h |
| February | 8.9°C-1.2°C | -1.2°C | 54 | 6.5 | 10.811 h |
| March | 12.6°C2.1°C | 2.1°C | 97 | 11.2 | 11.912 h |
| April | 17.7°C7.4°C | 7.4°C | 106 | 10.7 | 13.113 h |
| May | 22.3°C12.8°C | 12.8°C | 127 | 12.2 | 14.114 h |
| June | 25.0°C17.4°C | 17.4°C | 162 | 14.2 | 14.615 h |
| July | 28.4°C21.4°C | 21.4°C | 170 | 14.7 | 14.414 h |
| August | 29.8°C22.8°C | 22.8°C | 128 | 12.3 | 13.514 h |
| September, selected | 25.9°C19.2°C | 19.2°C | 186 | 14.1 | 12.412 h |
| October | 20.4°C13.0°C | 13.0°C | 196 | 12.4 | 11.311 h |
| November | 15.2°C6.5°C | 6.5°C | 76 | 8.6 | 10.310 h |
| December | 10.2°C0.9°C | 0.9°C | 49 | 6.5 | 9.810 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
- Kazo in SeptemberJapan · 9 kmHigh 26.1°C · Low 19.3°C · 186 mm rain
- Kumagaya in SeptemberJapan · 14 kmHigh 25.9°C · Low 19.3°C · 221 mm rain
- Ageo in SeptemberJapan · 14 kmHigh 26.0°C · Low 19.3°C · 186 mm rain
- Kukichūō in SeptemberJapan · 14 kmHigh 26.2°C · Low 19.4°C · 171 mm rain
- Sakado in SeptemberJapan · 17 kmHigh 25.7°C · Low 19.2°C · 186 mm rain
- Kawagoe in SeptemberJapan · 18 kmHigh 25.6°C · Low 19.0°C · 186 mm rain
- Tatebayashi in SeptemberJapan · 20 kmHigh 25.7°C · Low 18.9°C · 221 mm rain
- Saitama in SeptemberJapan · 22 kmHigh 26.3°C · Low 19.6°C · 171 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 Kōnosu) is explained once on the Kōnosu year overview and on the Sources, method and limits page.
Kawagoe, Ageo and Kazo lie in the same rainfall cell, so their rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.