Click on a day for an hourly weather forecast
The temperatures in Cavan in September are quite cold with temperatures between 9°C and 15°C, warm clothes are a must.
You can expect about 3 to 8 days of rain in Cavan 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 Cavan in September 2025.
If you’re planning to visit Cavan in the near future, we highly recommend that you review the 14 day weather forecast for Cavan before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 6° / 2° | 8 | 18 | 5 | 59 mm | Awful | Cavan in January |
| February | 7° / 2° | 8 | 16 | 5 | 59 mm | Awful | Cavan in February |
| March | 9° / 2° | 7 | 21 | 3 | 51 mm | Awful | Cavan in March |
| April | 11° / 4° | 4 | 24 | 1 | 41 mm | Ok | Cavan in April |
| May | 14° / 6° | 6 | 25 | 0 | 55 mm | Good | Cavan in May |
| June | 16° / 8° | 5 | 25 | 0 | 66 mm | Good | Cavan in June |
| July | 17° / 10° | 7 | 24 | 0 | 78 mm | Ok | Cavan in July |
| August | 17° / 10° | 6 | 25 | 0 | 66 mm | Good | Cavan in August |
| September | 15° / 9° | 5 | 25 | 0 | 44 mm | Good | Cavan in September |
| October | 12° / 7° | 6 | 25 | 0 | 62 mm | Ok | Cavan in October |
| November | 9° / 4° | 7 | 22 | 1 | 63 mm | Bad | Cavan in November |
| December | 7° / 3° | 7 | 22 | 2 | 57 mm | Awful | Cavan in December |