Iyo, Japan climate
Cfa Humid subtropical
Iyo has a seasonal mild-temperate climate (Humid subtropical, Köppen Cfa). The hottest month is August with an average daily high near 31°C, while the coldest is January averaging around 3°C at night. Precipitation totals about 1307 mm a year and is strongly seasonal — July alone averages 226 mm while January barely receives 40 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)Iyo climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°C) | 10 | 11 | 14 | 18 | 23 | 25 | 30 | 31 | 28 | 24 | 18 | 13 |
| Avg temp (°C) | 7 | 7 | 10 | 14 | 19 | 22 | 26 | 28 | 25 | 20 | 14 | 9 |
| Avg low (°C) | 3 | 3 | 6 | 10 | 15 | 19 | 23 | 25 | 22 | 16 | 10 | 5 |
| Precipitation (mm) | 40 | 63 | 91 | 96 | 112 | 196 | 226 | 94 | 152 | 109 | 66 | 62 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°C) | 10 | 11 | 14 | 18 | 23 | 25 |
| Avg temp (°C) | 7 | 7 | 10 | 14 | 19 | 22 |
| Avg low (°C) | 3 | 3 | 6 | 10 | 15 | 19 |
| Precipitation (mm) | 40 | 63 | 91 | 96 | 112 | 196 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°C) | 30 | 31 | 28 | 24 | 18 | 13 |
| Avg temp (°C) | 26 | 28 | 25 | 20 | 14 | 9 |
| Avg low (°C) | 23 | 25 | 22 | 16 | 10 | 5 |
| Precipitation (mm) | 226 | 94 | 152 | 109 | 66 | 62 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 72 | 69 | 67 | 65 | 69 | 82 | 72 | 63 | 68 | 60 | 63 | 68 |
| Relative humidity (%) | 76 | 74 | 74 | 76 | 78 | 83 | 85 | 82 | 80 | 76 | 75 | 76 |
| Wind speed (m/s) | 3.2 | 3.2 | 3.0 | 2.5 | 2.0 | 1.7 | 1.8 | 1.9 | 2.5 | 2.9 | 2.9 | 3.1 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 72 | 69 | 67 | 65 | 69 | 82 |
| Relative humidity (%) | 76 | 74 | 74 | 76 | 78 | 83 |
| Wind speed (m/s) | 3.2 | 3.2 | 3.0 | 2.5 | 2.0 | 1.7 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 72 | 63 | 68 | 60 | 63 | 68 |
| Relative humidity (%) | 85 | 82 | 80 | 76 | 75 | 76 |
| Wind speed (m/s) | 1.8 | 1.9 | 2.5 | 2.9 | 2.9 | 3.1 |
Methodology & sources
Temperature & precipitation — the official 1991–2020 climate normals from the Japan Meteorological Agency, measured at Matsuyama-minamiyoshida, about 8 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.