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Otaru sits on Hokkaido’s Japan Sea coast, 33 km northwest of Sapporo, and its climate is colder and snowier than anywhere in Honshu. The city averages about 630 cm of snowfall a year, with snow depth reaching one metre in February, while summer stays mild with an August high of just 24°C (75°F). This month-by-month breakdown gives the temperatures, rain and snow to expect, so you can pack correctly for your trip. Plan the whole visit from our full Otaru city guide.
Otaru Weather by Month: Winter (December to February)
Winter is long and snowy. December averages a high of 2°C (36°F) and a low of -4°C (25°F), with around 100 mm of precipitation mostly falling as snow. January is the coldest month at -1°C (30°F) high and -7°C (19°F) low. The Japan Sea effect brings lake-like snow bands that can drop 30 cm in a single day, and the streets, canal and Tenguyama ropeway are all active through February. If you want the snow without the deep freeze, check the best time to visit Otaru guide for the festival calendar.
Otaru Weather by Month: Spring (March to May)
Spring warms slowly because the sea stays cold. March still sees highs around 4°C (39°F) and lows of -3°C (27°F) with 75 mm of precipitation and lingering snow on the ground. By April, highs reach 10°C (50°F) and cherry blossoms open in Temiya Park in late April to early May, about three weeks later than Tokyo. May brings highs of 16°C (61°F), lows of 7°C (45°F) and only 65 mm of rain, the driest stretch of the year. Pack a light jacket for evenings even in May. For hotel options by district, see the where to stay in Otaru guide.
Otaru Weather by Month: Summer (June to August)
Summer is the most comfortable season in Hokkaido and the reason many Japanese travelers flee Tokyo in July and August. June averages 20°C (68°F) high and 12°C (54°F) low with 70 mm of rain. July reaches 23°C (73°F) high and 16°C (61°F) low with 90 mm of rain. August is the warmest month at 24°C (75°F) high and 18°C (64°F) low, and it is also the wettest at about 110 mm. The sea off Shioya and Otaru beaches warms to 20 to 21°C (68 to 70°F), swimmable for a few weeks in August. See the things to do in Otaru guide for summer outdoor options.
Otaru Weather by Month: Autumn (September to November)
Autumn is short, bright and increasingly cold. September still feels mild at 21°C (70°F) high and 13°C (55°F) low, but it is the wettest month at about 130 mm of rain. October drops to 15°C (59°F) high and 6°C (43°F) low, and the leaves on Mount Tengu and along the Asarigawa river turn colour in mid to late October. November brings highs of 8°C (46°F) and the first serious snowfalls usually arrive by late November. Layer up and expect rain and wind off the sea. The Otaru neighborhoods guide covers which district to base yourself in.
Otaru Weather by Month: Climate Data Table
The table below summarises average conditions. Temperatures are daytime highs and overnight lows; rainfall is total monthly precipitation in millimetres. Snowfall is heaviest from December to February and essentially absent from June to September. For arrival and transport details, see the Otaru travel tips page.
| Month | High | Low | Rain (mm) | Sea Temp |
|---|---|---|---|---|
| January | -1°C (30°F) | -7°C (19°F) | 105 | 6°C (43°F) |
| February | 0°C (32°F) | -7°C (19°F) | 80 | 5°C (41°F) |
| March | 4°C (39°F) | -3°C (27°F) | 75 | 5°C (41°F) |
| April | 10°C (50°F) | 2°C (36°F) | 60 | 7°C (45°F) |
| May | 16°C (61°F) | 7°C (45°F) | 65 | 10°C (50°F) |
| June | 20°C (68°F) | 12°C (54°F) | 70 | 14°C (57°F) |
| July | 23°C (73°F) | 16°C (61°F) | 90 | 18°C (64°F) |
| August | 24°C (75°F) | 18°C (64°F) | 110 | 21°C (70°F) |
| September | 21°C (70°F) | 13°C (55°F) | 130 | 20°C (68°F) |
| October | 15°C (59°F) | 6°C (43°F) | 110 | 16°C (61°F) |
| November | 8°C (46°F) | 1°C (34°F) | 100 | 12°C (54°F) |
| December | 2°C (36°F) | -4°C (25°F) | 100 | 9°C (48°F) |
For a seasonal overview of when to go and what to pack, read the best time to visit guide, and see the Otaru events and festivals calendar to plan around the Snow Light Path.
