Temperature
Cold by day, cold at night.
Cold days.

Cold by day, cold at night.
Rain is frequent. About 14 wet days this month.
Sunshine is limited, with cloud often dominating.
Humidity is rarely noticeable in the cool air.
In December, afternoons feel about 37° and nights feel near 34°.
Mostly cloudy skies this month.
Breezy December days can feel brisker in open spots.
December late afternoons are around 45°F, and early evening stays near 44°F.
| Month | High°F | Low°F | Rainin | Wet days | Sunh | Humidity% |
|---|---|---|---|---|---|---|
| Jan | 46 | 39 | 2.9 | 14 | 4.0 | 85 |
| Feb | 47 | 40 | 2.5 | 12 | 5.5 | 83 |
| Mar | 49 | 40 | 2.4 | 13 | 7.1 | 81 |
| Apr | 53 | 43 | 2.4 | 13 | 9.4 | 79 |
| May | 58 | 47 | 2.8 | 14 | 10.9 | 78 |
| Jun | 62 | 52 | 3.0 | 14 | 10.7 | 80 |
| Jul | 65 | 55 | 3.3 | 15 | 9.9 | 81 |
| Aug | 64 | 55 | 3.3 | 15 | 9.1 | 83 |
| Sep | 62 | 53 | 2.9 | 13 | 7.7 | 83 |
| Oct | 56 | 48 | 3.6 | 14 | 5.7 | 84 |
| Nov | 51 | 44 | 3.3 | 14 | 4.4 | 86 |
| Dec | 47 | 40 | 3.3 | 14 | 3.4 | 87 |
Similar climates
Want a side-by-side climate view? Compare Belfast with Brighton.
Typical monthly values are based on long-term climate records. Useful for planning, not a forecast. Check the weather before you travel.
Sunshine: source type is not yet identified at metric level.
Local microclimates can vary by beach, neighborhood, trail, or elevation.
Last updated: Aug 27, 2026
Data & methodology