Sapporo weather by month
Sapporo runs from about -5°C in January to 23°C in August, with October the wettest month at 166 mm.
warmest month
August
23°C
coolest month
January
-5°C
wettest month
October
166 mm
worst air month
March
16 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -5°C | 96 mm | 153 h | 10 |
| February | -5°C | 61 mm | 184 h | 12 |
| March | -3°C | 68 mm | 261 h | 16 |
| April | 9°C | 74 mm | 263 h | 10 |
| May | 12°C | 95 mm | 260 h | 11 |
| June | 17°C | 111 mm | 299 h | 9 |
| July | 22°C | 133 mm | 293 h | 8 |
| August | 23°C | 151 mm | 272 h | 8 |
| September | 18°C | 68 mm | 285 h | 9 |
| October | 12°C | 166 mm | 231 h | 9 |
| November | 4°C | 138 mm | 176 h | 12 |
| December | -5°C | 54 mm | 184 h | 8 |
About 2,861 hours of sun a year. Roughly 122 rainy days a year.
These are long-run climate normals, not a forecast. A given year can sit well outside them. PM2.5 is a global model: near the coast it counts sea salt as fine particulate and reads high against ground stations, sometimes by a factor of two. Use the shape of the year, not the absolute number.
where these numbers come from
- · Temperature, rainfall and sunshine: ECMWF ERA5 reanalysis climate normals via Open-Meteo (CC BY 4.0), fetched once and stored.
- · PM2.5: Copernicus CAMS reanalysis, monthly means. Modelled, not station readings; near coasts CAMS counts sea salt as PM2.5 and reads high.
Last reviewed 2026-05-23. Full method, licences and the list of sources we rejected are on the methodology page.