Saku, Japan climate
Cfa Humid subtropical
Saku has a strongly seasonal cool-temperate climate (Humid subtropical, Köppen Cfa). The hottest month is August with an average daily high near 85°F, while the coldest is January averaging around 18°F at night. Precipitation totals about 42 inches a year and is strongly seasonal — September alone averages 6.3 inches while December barely receives 1.17 inches.
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)Saku climate normals (1991–2020)
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 38 | 40 | 49 | 61 | 71 | 76 | 83 | 85 | 76 | 65 | 55 | 44 |
| Avg temp (°F) | 28 | 30 | 37 | 48 | 58 | 65 | 72 | 73 | 65 | 54 | 43 | 33 |
| Avg low (°F) | 18 | 19 | 26 | 35 | 47 | 57 | 64 | 65 | 58 | 45 | 33 | 24 |
| Precipitation (in) | 1.3 | 1.4 | 2.7 | 2.7 | 3.6 | 5.1 | 5.9 | 4.7 | 6.3 | 5.2 | 2.0 | 1.2 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Avg high (°F) | 38 | 40 | 49 | 61 | 71 | 76 |
| Avg temp (°F) | 28 | 30 | 37 | 48 | 58 | 65 |
| Avg low (°F) | 18 | 19 | 26 | 35 | 47 | 57 |
| Precipitation (in) | 1.3 | 1.4 | 2.7 | 2.7 | 3.6 | 5.1 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Avg high (°F) | 83 | 85 | 76 | 65 | 55 | 44 |
| Avg temp (°F) | 72 | 73 | 65 | 54 | 43 | 33 |
| Avg low (°F) | 64 | 65 | 58 | 45 | 33 | 24 |
| Precipitation (in) | 5.9 | 4.7 | 6.3 | 5.2 | 2.0 | 1.2 |
Sky & atmosphere
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cloud cover (%) | 63 | 64 | 65 | 65 | 69 | 81 | 79 | 70 | 75 | 70 | 62 | 61 |
| Relative humidity (%) | 90 | 87 | 82 | 76 | 75 | 79 | 81 | 81 | 83 | 84 | 85 | 88 |
| Wind speed (mph) | 5.4 | 5.8 | 5.7 | 4.9 | 4.0 | 3.1 | 3.0 | 2.8 | 3.0 | 3.3 | 3.8 | 4.8 |
| Jan – Jun | Jan | Feb | Mar | Apr | May | Jun |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 63 | 64 | 65 | 65 | 69 | 81 |
| Relative humidity (%) | 90 | 87 | 82 | 76 | 75 | 79 |
| Wind speed (mph) | 5.4 | 5.8 | 5.7 | 4.9 | 4.0 | 3.1 |
| Jul – Dec | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|
| Cloud cover (%) | 79 | 70 | 75 | 70 | 62 | 61 |
| Relative humidity (%) | 81 | 81 | 83 | 84 | 85 | 88 |
| Wind speed (mph) | 3.0 | 2.8 | 3.0 | 3.3 | 3.8 | 4.8 |
Methodology & sources
Temperature & precipitation — the official 1991–2020 climate normals from the Japan Meteorological Agency, measured at Tateshina, about 16 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.