Click on a day for an hourly weather forecast
The temperatures in Rathmullan in September are usually low and can range between 10°C and 15°C.
You can expect rain for roughly half of the month of September in Rathmullan. 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 Rathmullan in September 2025.
If you’re planning to visit Rathmullan in the near future, we highly recommend that you review the 14 day weather forecast for Rathmullan before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 7° / 3° | 10 | 18 | 3 | 105 mm | Awful | Rathmullan in January |
| February | 7° / 3° | 9 | 15 | 5 | 105 mm | Awful | Rathmullan in February |
| March | 9° / 4° | 8 | 21 | 2 | 85 mm | Awful | Rathmullan in March |
| April | 11° / 5° | 6 | 24 | 1 | 65 mm | Ok | Rathmullan in April |
| May | 13° / 7° | 9 | 23 | 0 | 100 mm | Bad | Rathmullan in May |
| June | 16° / 10° | 8 | 22 | 0 | 120 mm | Ok | Rathmullan in June |
| July | 17° / 11° | 11 | 20 | 0 | 154 mm | Ok | Rathmullan in July |
| August | 16° / 11° | 10 | 21 | 0 | 153 mm | Ok | Rathmullan in August |
| September | 15° / 10° | 9 | 21 | 0 | 103 mm | Ok | Rathmullan in September |
| October | 13° / 8° | 9 | 22 | 0 | 128 mm | Bad | Rathmullan in October |
| November | 9° / 6° | 9 | 20 | 0 | 116 mm | Bad | Rathmullan in November |
| December | 7° / 4° | 10 | 19 | 2 | 105 mm | Awful | Rathmullan in December |