Climate averages 1991–2020
Iwakuni weather
in May.
A warm, wet month: the 5th warmest and the 8th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a warm month in Iwakuni: daytime highs average 22.2°C and nights cool to about 14.8°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 158 mm of rain on roughly 10 days, which makes May a wet month (the 8th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 55 min on an average May day.
The nearest other city in this atlas is Hatsukaichi (23 km away). In May its highs average 23.3°C, 1.1°C warmer than Iwakuni, with 158 mm of rain.
Among the 303 cities listed in Japan, Iwakuni ranks joint 107th of 303 for the warmest May highs and joint 213th of 303 for the driest May (rainfall, lowest first). The mean May high of those 303 cities is 21.3°C; Iwakuni is 0.8°C warmer than that mean.
From May to June, average highs rise by 2.9°C to 25.1°C, and monthly rainfall rises from 158 mm to 234 mm.
The annual picture
May 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
Iwakuni climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 8.5°C2.8°C | 2.8°C | 50 | 6.2 | 10.210 h |
| February | 9.6°C2.8°C | 2.8°C | 69 | 8.0 | 10.911 h |
| March | 13.0°C5.3°C | 5.3°C | 116 | 10.1 | 11.912 h |
| April | 17.8°C9.9°C | 9.9°C | 138 | 9.7 | 13.013 h |
| May, selected | 22.2°C14.8°C | 14.8°C | 158 | 10.3 | 13.914 h |
| June | 25.1°C19.1°C | 19.1°C | 234 | 13.9 | 14.414 h |
| July | 28.7°C23.4°C | 23.4°C | 255 | 15.2 | 14.214 h |
| August | 29.8°C24.4°C | 24.4°C | 169 | 14.4 | 13.413 h |
| September | 26.5°C20.9°C | 20.9°C | 185 | 11.7 | 12.412 h |
| October | 21.5°C15.5°C | 15.5°C | 116 | 8.0 | 11.411 h |
| November | 16.1°C10.1°C | 10.1°C | 72 | 7.1 | 10.410 h |
| December | 10.8°C5.1°C | 5.1°C | 60 | 6.7 | 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
May in nearby cities
- Hatsukaichi in MayJapan · 23 kmHigh 23.3°C · Low 14.4°C · 158 mm rain
- Kure in MayJapan · 33 kmHigh 20.2°C · Low 14.6°C · 155 mm rain
- Hiroshima in MayJapan · 34 kmHigh 22.8°C · Low 13.8°C · 143 mm rain
- Shūnan in MayJapan · 37 kmHigh 20.5°C · Low 12.8°C · 169 mm rain
- Higashihiroshima in MayJapan · 55 kmHigh 21.7°C · Low 13.0°C · 134 mm rain
- Hōfu in MayJapan · 61 kmHigh 22.5°C · Low 14.2°C · 162 mm rain
- Matsuyama in MayJapan · 62 kmHigh 23.1°C · Low 15.2°C · 154 mm rain
- Yamaguchi in MayJapan · 69 kmHigh 22.4°C · Low 13.2°C · 150 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 Iwakuni) is explained once on the Iwakuni year overview and on the Sources, method and limits page.
Hatsukaichi lies in the same rainfall cell, so its rainfall figures are identical to these; temperatures differ because they come from smaller 0.1° cells.