Weather In Japan In September 2024. In general, the average temperature in japan at the beginning of september is 30.6 ° c. In tokyo, in september, it is raining for 12.5 days, with typically 46mm (1.81) of accumulated precipitation.

Tropical storm shanshan made landfall. Expect 27°c daytime maximum temperatures in the shade with on average 4 hours of sunshine per day in japan in september.