Kosai, Japan climate
Cfa Humid subtropical
Kosai has a seasonal mild-temperate climate (Humid subtropical, Köppen Cfa). The hottest month is August with an average daily high near 32°C, while the coldest is January averaging around 2°C at night. Precipitation totals about 1843 mm a year and is strongly seasonal — September alone averages 246 mm while January barely receives 59 mm.
Temperature & precipitation
Daily high–low temperature range with the monthly average, plus monthly precipitation · 1991–2020 normals · hover a month for the exact figuresHours of sunshine per day
Estimated sunny hours each month — daylight length × clear-sky fraction · 1991–2020 monthly cloud cover (NASA POWER)Kosai climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 11 | 12 | 15 | 20 | 24 | 27 | 30 | 32 | 29 | 24 | 19 | 13 |
| Avg temp (°C) | 6 | 7 | 10 | 15 | 19 | 23 | 26 | 28 | 25 | 20 | 14 | 9 |
| Avg low (°C) | 2 | 3 | 6 | 11 | 15 | 19 | 23 | 25 | 22 | 16 | 10 | 5 |
| Precipitation (mm) | 59 | 77 | 147 | 179 | 192 | 225 | 209 | 127 | 246 | 207 | 113 | 63 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 11 | 12 | 15 | 20 | 24 | 27 |
| Avg temp (°C) | 6 | 7 | 10 | 15 | 19 | 23 |
| Avg low (°C) | 2 | 3 | 6 | 11 | 15 | 19 |
| Precipitation (mm) | 59 | 77 | 147 | 179 | 192 | 225 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 30 | 32 | 29 | 24 | 19 | 13 |
| Avg temp (°C) | 26 | 28 | 25 | 20 | 14 | 9 |
| Avg low (°C) | 23 | 25 | 22 | 16 | 10 | 5 |
| Precipitation (mm) | 209 | 127 | 246 | 207 | 113 | 63 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 57 | 59 | 60 | 62 | 67 | 79 | 70 | 56 | 65 | 62 | 56 | 54 |
| Relative humidity (%) | 82 | 80 | 78 | 78 | 79 | 83 | 85 | 83 | 83 | 83 | 83 | 83 |
| Wind speed (mph) | 3.7 | 3.9 | 3.8 | 3.4 | 2.9 | 2.4 | 2.3 | 2.3 | 2.5 | 2.6 | 2.8 | 3.3 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 57 | 59 | 60 | 62 | 67 | 79 |
| Relative humidity (%) | 82 | 80 | 78 | 78 | 79 | 83 |
| Wind speed (mph) | 3.7 | 3.9 | 3.8 | 3.4 | 2.9 | 2.4 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 70 | 56 | 65 | 62 | 56 | 54 |
| Relative humidity (%) | 85 | 83 | 83 | 83 | 83 | 83 |
| Wind speed (mph) | 2.3 | 2.3 | 2.5 | 2.6 | 2.8 | 3.3 |
Methodology & sources
Temperature & precipitation — the official 1991–2020 climate normals from the Japan Meteorological Agency, measured at Hamamatsu, about 18 km from the city centre.
Cloud, humidity, wind & sunshine — modelled estimates from NASA POWER, NASA's satellite-and-reanalysis climatology. This is the standard global source for atmospheric variables, which are not measured at most weather stations.