Sapporo Weather in September

The climate in Sapporo during September can be summarized as mild and wet.

September is in the fall / autumn in Sapporo and is typically the 3rd warmest month of the year. Daytime maximum temperatures average around 22°C (72°F), whilst at night 13°C (56°F) is normal.

On average September is the 2nd wettest month of the year in Sapporo with around 139mm 5.5 inches of rain making it a wet time to visit. This rainfall is typically spread over 18 days, although this may vary considerably.

On the flip side this corresponds to an average of 6 hours of sunshine per day.

The data used in these monthly averages covers a period of over 100 years right up until last year. As such they are a valid prediction of what to expect for the weather in Sapporo in September 2025.