Click on a day for an hourly weather forecast
The temperatures in Calw in September are comfortable with low of 11°C and and high up to 21°C.
You can expect about 3 to 8 days of rain in Calw 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 Calw in September 2026.
If you’re planning to visit Calw in the near future, we highly recommend that you review the 14 day weather forecast for Calw before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 4° / -1° | 7 | 12 | 12 | 72 mm | Awful | Calw in January |
| February | 6° / 0° | 7 | 12 | 9 | 62 mm | Awful | Calw in February |
| March | 11° / 2° | 6 | 20 | 5 | 52 mm | Bad | Calw in March |
| April | 16° / 5° | 5 | 23 | 2 | 48 mm | Ok | Calw in April |
| May | 19° / 8° | 8 | 23 | 0 | 109 mm | Ok | Calw in May |
| June | 23° / 12° | 5 | 25 | 0 | 97 mm | Perfect | Calw in June |
| July | 25° / 14° | 5 | 26 | 0 | 100 mm | Perfect | Calw in July |
| August | 25° / 14° | 5 | 26 | 0 | 80 mm | Perfect | Calw in August |
| September | 21° / 11° | 3 | 27 | 0 | 52 mm | Good | Calw in September |
| October | 15° / 7° | 5 | 26 | 0 | 58 mm | Good | Calw in October |
| November | 10° / 4° | 6 | 22 | 3 | 67 mm | Bad | Calw in November |
| December | 6° / 1° | 8 | 15 | 8 | 76 mm | Awful | Calw in December |