Climate averages 1991–2020
Karatsu weather
in August.
A hot, wet month: the warmest and the 9th driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
August is a hot month in Karatsu: daytime highs average 30.4°C and nights cool to about 25.1°C. By daytime temperature it is the warmest month of the year.
Expect about 162 mm of rain on roughly 14 days, which makes August a wet month (the 9th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 13 h 24 min on an average August day.
The nearest other city in this atlas is Itoshima (23 km away). In August its highs average 30.0°C, about as warm as Karatsu, with 163 mm of rain.
Among the 303 cities listed in Japan, Karatsu ranks joint 62nd of 303 for the warmest August highs and joint 194th of 303 for the driest August (rainfall, lowest first). The mean August high of those 303 cities is 29.2°C; Karatsu is 1.2°C warmer than that mean.
From August to September, average highs fall by 3.4°C to 27.0°C, and monthly rainfall rises from 162 mm to 179 mm.
The annual picture
August 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
Karatsu climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 9.0°C4.5°C | 4.5°C | 76 | 11.9 | 10.210 h |
| February | 10.2°C4.6°C | 4.6°C | 80 | 10.5 | 11.011 h |
| March | 13.6°C7.1°C | 7.1°C | 124 | 11.6 | 12.012 h |
| April | 18.4°C11.0°C | 11.0°C | 134 | 11.0 | 13.013 h |
| May | 22.7°C15.6°C | 15.6°C | 143 | 10.3 | 13.914 h |
| June | 25.6°C19.8°C | 19.8°C | 277 | 14.7 | 14.314 h |
| July | 29.1°C24.1°C | 24.1°C | 260 | 15.3 | 14.114 h |
| August, selected | 30.4°C25.1°C | 25.1°C | 162 | 13.7 | 13.413 h |
| September | 27.0°C21.8°C | 21.8°C | 179 | 12.6 | 12.412 h |
| October | 22.1°C16.7°C | 16.7°C | 103 | 8.1 | 11.411 h |
| November | 16.8°C11.5°C | 11.5°C | 94 | 9.3 | 10.510 h |
| December | 11.4°C6.7°C | 6.7°C | 81 | 11.1 | 10.010 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
August in nearby cities
- Itoshima in AugustJapan · 23 kmHigh 30.0°C · Low 25.1°C · 163 mm rain
- Maebaru-chūō in AugustJapan · 25 kmHigh 29.7°C · Low 25.1°C · 163 mm rain
- Sasebo in AugustJapan · 38 kmHigh 30.1°C · Low 25.2°C · 178 mm rain
- Saga in AugustJapan · 39 kmHigh 30.4°C · Low 23.9°C · 181 mm rain
- Fukuoka in AugustJapan · 45 kmHigh 30.7°C · Low 24.6°C · 171 mm rain
- Kasuga in AugustJapan · 47 kmHigh 31.1°C · Low 24.0°C · 171 mm rain
- Tosu in AugustJapan · 51 kmHigh 30.8°C · Low 23.6°C · 175 mm rain
- Kurume in AugustJapan · 53 kmHigh 30.8°C · Low 23.5°C · 175 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 Karatsu) is explained once on the Karatsu year overview and on the Sources, method and limits page.