Click on a day for an hourly weather forecast
The weather in Hamilton in September is very hot. The average temperatures are between 26°C and 27°C, drinking water regularly is advisable.
You can expect rain for roughly half of the month of September in Hamilton. 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 Hamilton in September 2025.
If you’re planning to visit Hamilton in the near future, we highly recommend that you review the 14 day weather forecast for Hamilton before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 19° / 17° | 7 | 24 | 0 | 168 mm | Ok | Hamilton in January |
| February | 19° / 17° | 6 | 23 | 0 | 142 mm | Good | Hamilton in February |
| March | 19° / 17° | 6 | 25 | 0 | 123 mm | Good | Hamilton in March |
| April | 20° / 18° | 4 | 26 | 0 | 80 mm | Good | Hamilton in April |
| May | 22° / 20° | 4 | 27 | 0 | 88 mm | Good | Hamilton in May |
| June | 24° / 24° | 7 | 23 | 0 | 171 mm | Good | Hamilton in June |
| July | 27° / 26° | 8 | 23 | 0 | 169 mm | Good | Hamilton in July |
| August | 28° / 27° | 9 | 22 | 0 | 205 mm | Good | Hamilton in August |
| September | 27° / 26° | 8 | 22 | 0 | 228 mm | Good | Hamilton in September |
| October | 25° / 24° | 5 | 26 | 0 | 174 mm | Perfect | Hamilton in October |
| November | 23° / 21° | 5 | 25 | 0 | 129 mm | Perfect | Hamilton in November |
| December | 21° / 19° | 4 | 27 | 0 | 104 mm | Good | Hamilton in December |