Click on a day for an hourly weather forecast
The temperatures in Clanwilliam in September are quite cold with temperatures between 8°C and 20°C, warm clothes are a must.
There is little to no rain in Clanwilliam during September, so it’s a lot easier to explore the city. Just remember to dress in warm layers, as it can still get pretty chilly.
Our weather forecast can give you a great sense of what weather to expect in Clanwilliam in September 2025.
If you’re planning to visit Clanwilliam in the near future, we highly recommend that you review the 14 day weather forecast for Clanwilliam before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 30° / 17° | 2 | 29 | 0 | 25 mm | Good | Clanwilliam in January |
| February | 29° / 18° | 1 | 27 | 0 | 23 mm | Good | Clanwilliam in February |
| March | 27° / 16° | 1 | 30 | 0 | 19 mm | Perfect | Clanwilliam in March |
| April | 23° / 13° | 1 | 29 | 0 | 24 mm | Perfect | Clanwilliam in April |
| May | 19° / 10° | 2 | 29 | 0 | 24 mm | Good | Clanwilliam in May |
| June | 15° / 7° | 3 | 27 | 0 | 36 mm | Good | Clanwilliam in June |
| July | 15° / 6° | 2 | 29 | 1 | 21 mm | Good | Clanwilliam in July |
| August | 16° / 6° | 2 | 28 | 1 | 21 mm | Good | Clanwilliam in August |
| September | 20° / 8° | 0 | 30 | 0 | 9 mm | Good | Clanwilliam in September |
| October | 24° / 11° | 1 | 30 | 0 | 13 mm | Perfect | Clanwilliam in October |
| November | 25° / 13° | 1 | 29 | 0 | 12 mm | Perfect | Clanwilliam in November |
| December | 28° / 15° | 1 | 30 | 0 | 31 mm | Perfect | Clanwilliam in December |