Climate averages 1991–2020
Hiroshima weather
in October.
A mild, wet month: the 6th warmest and the 5th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
October is a mild month in Hiroshima: daytime highs average 21.5°C and nights cool to about 13.7°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 109 mm of rain on roughly 8 days, which makes October a wet month (the 5th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 11 h 21 min on an average October day.
The nearest other city in this atlas is Hatsukaichi (12 km away). In October its highs average 22.0°C, about as warm as Hiroshima, with 116 mm of rain.
Among the 303 cities listed in Japan, Hiroshima ranks joint 69th of 303 for the warmest October highs and joint 35th of 303 for the driest October (rainfall, lowest first). The mean October high of those 303 cities is 20.4°C; Hiroshima is 1.2°C warmer than that mean.
From October to November, average highs fall by 5.7°C to 15.9°C, and monthly rainfall falls from 109 mm to 71 mm.
The annual picture
October 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
Hiroshima climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 8.0°C1.1°C | 1.1°C | 55 | 9.5 | 10.110 h |
| February | 9.3°C1.3°C | 1.3°C | 68 | 9.9 | 10.911 h |
| March | 13.1°C3.9°C | 3.9°C | 110 | 11.7 | 11.912 h |
| April | 18.3°C8.7°C | 8.7°C | 124 | 10.3 | 13.013 h |
| May | 22.8°C13.8°C | 13.8°C | 143 | 10.3 | 13.914 h |
| June | 25.8°C18.5°C | 18.5°C | 215 | 14.3 | 14.414 h |
| July | 29.1°C22.8°C | 22.8°C | 251 | 16.1 | 14.214 h |
| August | 30.4°C23.8°C | 23.8°C | 157 | 14.0 | 13.413 h |
| September | 26.9°C19.9°C | 19.9°C | 188 | 12.6 | 12.412 h |
| October, selected | 21.5°C13.7°C | 13.7°C | 109 | 8.2 | 11.311 h |
| November | 15.9°C8.2°C | 8.2°C | 71 | 8.1 | 10.410 h |
| December | 10.3°C3.4°C | 3.4°C | 64 | 9.6 | 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
October in nearby cities
- Hatsukaichi in OctoberJapan · 12 kmHigh 22.0°C · Low 14.5°C · 116 mm rain
- Kure in OctoberJapan · 22 kmHigh 20.8°C · Low 16.0°C · 113 mm rain
- Higashihiroshima in OctoberJapan · 26 kmHigh 20.8°C · Low 13.2°C · 102 mm rain
- Iwakuni in OctoberJapan · 34 kmHigh 21.5°C · Low 15.5°C · 116 mm rain
- Mihara in OctoberJapan · 58 kmHigh 21.8°C · Low 14.2°C · 103 mm rain
- Imabari in OctoberJapan · 62 kmHigh 21.4°C · Low 16.8°C · 148 mm rain
- Shūnan in OctoberJapan · 67 kmHigh 20.1°C · Low 13.4°C · 113 mm rain
- Matsuyama in OctoberJapan · 69 kmHigh 22.1°C · Low 16.0°C · 141 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 Hiroshima) is explained once on the Hiroshima year overview and on the Sources, method and limits page.