Click on a day for an hourly weather forecast
The temperatures in Belfast in August are usually low and can range between 11°C and 17°C.
You can expect rain for roughly half of the month of August in Belfast. 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 Belfast in August 2025.
If you’re planning to visit Belfast in the near future, we highly recommend that you review the 14 day weather forecast for Belfast before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 7° / 3° | 11 | 17 | 4 | 105 mm | Awful | Belfast in January |
| February | 7° / 3° | 11 | 13 | 5 | 113 mm | Awful | Belfast in February |
| March | 9° / 3° | 10 | 19 | 2 | 99 mm | Awful | Belfast in March |
| April | 11° / 5° | 7 | 22 | 1 | 82 mm | Bad | Belfast in April |
| May | 14° / 7° | 8 | 23 | 0 | 97 mm | Ok | Belfast in May |
| June | 16° / 10° | 8 | 22 | 0 | 121 mm | Ok | Belfast in June |
| July | 17° / 11° | 9 | 22 | 0 | 130 mm | Ok | Belfast in July |
| August | 17° / 11° | 10 | 21 | 0 | 149 mm | Ok | Belfast in August |
| September | 16° / 10° | 7 | 23 | 0 | 99 mm | Ok | Belfast in September |
| October | 13° / 8° | 10 | 21 | 0 | 132 mm | Bad | Belfast in October |
| November | 9° / 6° | 9 | 20 | 1 | 123 mm | Bad | Belfast in November |
| December | 7° / 4° | 9 | 20 | 2 | 110 mm | Awful | Belfast in December |