Kumamoto 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
Fair
Best time to visit: April – May, September – November
What is the weather like in Kumamoto in August?
In August, Kumamoto is hot: daytime highs average 30 °C, and even at night it stays warm at around 24 °C. The sea averages 27.8 °C – lovely and warm for swimming. Expect around 6 hours of sunshine a day. Rain is frequent, with about 13 rainy days and 185 mm in total. On about 19 days the thermometer climbs to 30 °C or more. The air is often humid and muggy. All in all, August is a so-so month for a holiday in Kumamoto.
August compared
How the weather changes from July to September. Tap a month to open it.
| JulyJul | AugustAug | SeptemberSep | |
|---|---|---|---|
| Score | 46 | 49 | 68 |
| Day | 29° | 30° | 28° |
| Night | 23° | 24° | 21° |
| Sea | 26° | 28° | 27° |
| Sun | 5 h | 6 h | 5 h |
| Rain days | 17 | 13 | 11 |
More details for August
- Daylight
- 13 h 24 min05:40 – 19:04
- UV index
- 10 · very highclear sky, noon (estimate)All months
- Muggy days
- 31 daysdew point 18 °C or moreAll months
- Wind
- 13 km/haverage daily peakAll months
- Cloud cover
- 61 %on averageAll months
- Hot days
- 19 days30 °C or moreAll months
- Time zone
- UTC+9Asia/Tokyo
How the score comes together
- Temperatureweight 50 %58 %
- Sunshineweight 20 %50 %
- Few rainy daysweight 30 %34 %
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
Kumamoto in August: quick answers
Is Kumamoto hot in August?
Yes. In August, Kumamoto is hot: daytime highs average 30 °C and nights stay around 24 °C. On about 19 days the thermometer climbs to 30 °C or more.
Can you swim in Kumamoto in August?
Yes. In August the sea averages 27.8 °C – lovely and warm for swimming.
Does it rain much in Kumamoto in August?
Rain is frequent, with about 13 rainy days and 185 mm in total.
Kumamoto month by month
The whole year in KumamotoAll 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