Click on a day for an hourly weather forecast
The temperatures in Hillsboro in September are comfortable with low of 12°C and and high up to 24°C.
You can expect about 3 to 8 days of rain in Hillsboro during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Hillsboro in September 2025.
If you’re planning to visit Hillsboro in the near future, we highly recommend that you review the 14 day weather forecast for Hillsboro before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 8° / 2° | 13 | 17 | 2 | 240 mm | Awful | Hillsboro in January |
| February | 9° / 2° | 11 | 15 | 3 | 171 mm | Awful | Hillsboro in February |
| March | 12° / 4° | 13 | 17 | 2 | 192 mm | Awful | Hillsboro in March |
| April | 15° / 5° | 8 | 21 | 1 | 136 mm | Ok | Hillsboro in April |
| May | 20° / 7° | 6 | 25 | 0 | 93 mm | Good | Hillsboro in May |
| June | 23° / 10° | 4 | 26 | 0 | 70 mm | Perfect | Hillsboro in June |
| July | 28° / 13° | 1 | 30 | 0 | 16 mm | Perfect | Hillsboro in July |
| August | 29° / 14° | 1 | 30 | 0 | 17 mm | Good | Hillsboro in August |
| September | 24° / 12° | 4 | 26 | 0 | 83 mm | Perfect | Hillsboro in September |
| October | 17° / 9° | 8 | 23 | 0 | 173 mm | Ok | Hillsboro in October |
| November | 11° / 5° | 12 | 18 | 0 | 201 mm | Bad | Hillsboro in November |
| December | 7° / 2° | 12 | 18 | 1 | 220 mm | Bad | Hillsboro in December |