Hakodate weather by month
Hakodate runs from about -2°C in December to 24°C in August, with August the wettest month at 160 mm.
warmest month
August
24°C
coolest month
December
-2°C
wettest month
August
160 mm
worst air month
March
14 µg/m³
The whole year, month by month.
| Month | Avg temp | Rain | Sun | PM2.5 |
|---|---|---|---|---|
| January | -1°C | 107 mm | 196 h | 4 |
| February | -2°C | 49 mm | 202 h | 9 |
| March | 0°C | 74 mm | 251 h | 14 |
| April | 9°C | 45 mm | 288 h | 10 |
| May | 13°C | 110 mm | 280 h | 10 |
| June | 17°C | 75 mm | 322 h | 10 |
| July | 22°C | 153 mm | 282 h | 9 |
| August | 24°C | 160 mm | 257 h | 7 |
| September | 20°C | 44 mm | 281 h | 6 |
| October | 14°C | 133 mm | 239 h | 6 |
| November | 6°C | 69 mm | 212 h | 9 |
| December | -2°C | 36 mm | 224 h | 5 |
About 3,034 hours of sun a year. Roughly 106 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 2026-05-27. Full method, licences and the list of sources we rejected are on the methodology page.