Hiroshima weather in August
Temperature, sea and sunshine in August: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in August
Good
Best time to visit: April – July, September – November
What is the weather like in Hiroshima in August?
In August, Hiroshima is hot: daytime highs average 29 °C, and even at night it stays warm at around 25 °C. The sea averages 26.5 °C – lovely and warm for swimming. The sun shines for around 7 hours a day. Rain is frequent, with about 11 rainy days and 139 mm in total. On about 11 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, August is a good month for a holiday in Hiroshima.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 66 | 63 | 73 |
| Day | 28° | 29° | 26° |
| Night | 24° | 25° | 22° |
| Sea | 24° | 27° | 26° |
| Sun | 6 h | 7 h | 6 h |
| Rain days | 13 | 11 | 11 |
More details for August
- Daylight
- 13 h 29 min05:31 – 19:00
- UV index
- 10 · very highclear sky, noon (estimate)All months
- Muggy days
- 31 daysdew point 18 °C or moreAll months
- Wind
- 15 km/haverage daily peakAll months
- Cloud cover
- 59 %on averageAll months
- Hot days
- 11 days30 °C or moreAll months
- Snow days
- 0 days1 cm or more of fresh snow
- Time zone
- UTC+9Asia/Tokyo
How the score comes together
- Temperatureweight 50 %73 %
- Sunshineweight 20 %62 %
- Few rainy daysweight 30 %49 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in August
- Swimwear
- Sunscreen
- Sunglasses & sun hat
- Light, breathable clothes
- Water bottle – drink plenty
- Insect repellent
- Rain jacket or umbrella
Hiroshima in August: quick answers
Is Hiroshima hot in August?
Yes. In August, Hiroshima is hot: daytime highs average 29 °C and nights stay around 25 °C. On about 11 days the thermometer climbs to 30 °C or more.
Can you swim in Hiroshima in August?
Yes. In August the sea averages 26.5 °C – lovely and warm for swimming.
Does it rain much in Hiroshima in August?
Rain is frequent, with about 11 rainy days and 139 mm in total.
Hiroshima month by month
The whole year in HiroshimaAll destinations: JapanWhere to go in AugustSea temperature in August
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences