Ryōtsu-minato, Japan Climate
The warmest month is August, with an average high of 27°C; the coldest is February, with an average low of 3°C. A normal year brings 1695 mm of precipitation.
Temperature through the year
The normal daily high and low. The line marks today.
- Normal low
- Normal high
- Reanalysis extreme high
- Reanalysis extreme low
Normals for Sep 25
- Normal high
- 23°C
- Normal low
- 20°C
- Reanalysis high
- 27°Cin 1992
- Reanalysis low
- 18°Cin 2010
- Chance of a wet day
- 50%
- Daylight
- 12 h 03 min
Month by month
Averages for 1991-2020. Wet days have at least 1 mm of precipitation in the reanalysis. Each month links to its own page.
| Month | Avg high | Avg low | Warmest | Coldest | Precipitation | Wet days |
|---|---|---|---|---|---|---|
| January | 6°C | 4°C | 13°C (1997) | -3°C (2018) | 167 mm | 24.8 |
| February | 6°C | 3°C | 15°C (2010) | -3°C (1996) | 110 mm | 19.8 |
| March | 8°C | 5°C | 15°C (2016) | 0°C (2013) | 105 mm | 18.6 |
| April | 12°C | 8°C | 22°C (2019) | 3°C (2012) | 93 mm | 12.0 |
| May | 17°C | 13°C | 26°C (2019) | 6°C (2013) | 93 mm | 12.4 |
| June | 21°C | 18°C | 28°C (2009) | 13°C (2017) | 120 mm | 12.0 |
| July | 25°C | 22°C | 32°C (2000) | 17°C (1996) | 198 mm | 15.5 |
| August | 27°C | 24°C | 34°C (1994) | 19°C (2009) | 146 mm | 15.5 |
| September | 24°C | 22°C | 32°C (2020) | 16°C (2001) | 144 mm | 15.0 |
| October | 19°C | 17°C | 27°C (2019) | 10°C (1997) | 146 mm | 15.5 |
| November | 14°C | 11°C | 21°C (2018) | 3°C (1992) | 171 mm | 21.0 |
| December | 9°C | 6°C | 18°C (2018) | -1°C (2002) | 202 mm | 24.8 |
| Year | 16°C | 13°C | 1695 mm | 207 |
Precipitation
Rain and melted snow together. The chance of a wet day is the share of days with at least 1 mm of precipitation in the reanalysis.
1695 mm in a normal year, most in December.
Chance of a wet day
- Chance of a wet day
Humidity and comfort
NASA POWER reanalysis, 1991-2020, for the grid cell around Ryōtsu-minato.
The muggiest month is August, when 95 percent of days are muggy or worse, with a mean dew point of 18°C or more.
| Month | Dew point | Humidity | Dry | Comfortable | Humid | Muggy | Oppressive | Miserable |
|---|---|---|---|---|---|---|---|---|
| January | 2°C | 79% | 100% | 0% | 0% | 0% | 0% | 0% |
| February | 1°C | 76% | 100% | 0% | 0% | 0% | 0% | 0% |
| March | 2°C | 74% | 100% | 0% | 0% | 0% | 0% | 0% |
| April | 6°C | 77% | 100% | 0% | 0% | 0% | 0% | 0% |
| May | 12°C | 80% | 66% | 30% | 5% | 0% | 0% | 0% |
| June | 17°C | 82% | 6% | 27% | 45% | 21% | 1% | 0% |
| July | 21°C | 85% | 0% | 0% | 10% | 41% | 45% | 4% |
| August | 22°C | 80% | 0% | 1% | 5% | 24% | 51% | 20% |
| September | 19°C | 76% | 3% | 15% | 27% | 33% | 20% | 2% |
| October | 13°C | 74% | 49% | 30% | 17% | 4% | 0% | 0% |
| November | 8°C | 75% | 92% | 8% | 0% | 0% | 0% | 0% |
| December | 4°C | 79% | 100% | 0% | 0% | 0% | 0% | 0% |
Comfort is judged by the day's mean dew point: dry below 13°C, comfortable to 16°C, humid to 18°C, muggy to 21°C, oppressive to 24°C, miserable above.
Clouds
Average share of the sky covered, from satellite (CERES and GEWEX SRB) by way of NASA POWER, 1991-2020.
The clearest month is August, with the sky 65 percent covered on average; the cloudiest is January, at 93 percent.
Wind
The mean wind speed over the whole day, from the MERRA-2 reanalysis by way of NASA POWER. Gusts run well above it.
The windiest month is January, averaging 27.0 km/h at 10 meters (33 feet) above the ground.
Daylight and sunshine
The longest day is Jun 18, with 14 h 49 min of daylight; the shortest is Dec 17, with 9 h 31 min.
- Day length
Solar energy
Average daily sunshine reaching the ground on a flat surface, in kilowatt-hours per square meter, clouds included.
Month pages
The weather in Ryōtsu-minato in each month, day by day.
What this means
A normal is the average of the thirty years 1991 to 2020, the period the World Meteorological Organization and NOAA use for comparison. It is an average, not a forecast: most days depart from it, and some by a long way.
Where no station record is within reach, the extremes shown are the highest and lowest the reanalysis produced for the date in 1991-2020, not measured records.
Cloud, humidity, wind and sunshine come from a reanalysis: a weather model run over the past with every observation fed in, averaged over a grid cell about 50 km across. It is consistent everywhere on Earth; it smooths local detail such as a lake shore or a valley.
More for this place
Nearby
Sources
Cloud, humidity, wind and sunshine, and temperature and precipitation: NASA POWER (MERRA-2, CERES and GEWEX SRB), 1991-2020. The data was obtained from the National Aeronautics and Space Administration (NASA) Langley Research Center's Prediction Of Worldwide Energy Resources (POWER) project funded through the NASA Earth Science Division: POWER Daily API v2, accessed 2026-09-24. Sun and moon: computed with the NOAA solar equations and Meeus.