Click on a day for an hourly weather forecast
The weather in Hamamatsu in September is hot. The average temperatures are between 22°C and 27°C.
You can expect rain for roughly half of the month of September in Hamamatsu. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in Hamamatsu in September 2025.
If you’re planning to visit Hamamatsu in the near future, we highly recommend that you review the 14 day weather forecast for Hamamatsu before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 9° / 3° | 5 | 24 | 2 | 72 mm | Bad | Hamamatsu in January |
| February | 10° / 4° | 6 | 21 | 1 | 100 mm | Ok | Hamamatsu in February |
| March | 13° / 7° | 7 | 24 | 0 | 171 mm | Bad | Hamamatsu in March |
| April | 17° / 11° | 8 | 22 | 0 | 218 mm | Ok | Hamamatsu in April |
| May | 22° / 15° | 7 | 24 | 0 | 240 mm | Ok | Hamamatsu in May |
| June | 24° / 19° | 10 | 20 | 0 | 292 mm | Good | Hamamatsu in June |
| July | 28° / 23° | 13 | 18 | 0 | 421 mm | Good | Hamamatsu in July |
| August | 30° / 25° | 10 | 21 | 0 | 297 mm | Ok | Hamamatsu in August |
| September | 27° / 22° | 10 | 20 | 0 | 312 mm | Good | Hamamatsu in September |
| October | 22° / 17° | 8 | 23 | 0 | 243 mm | Ok | Hamamatsu in October |
| November | 17° / 11° | 5 | 25 | 0 | 128 mm | Good | Hamamatsu in November |
| December | 11° / 6° | 5 | 25 | 1 | 89 mm | Ok | Hamamatsu in December |