Generally, you can anticipate the weather in Swansea in December is 5. Highs are expected to be 8 with low temperatures being around 6 celsius. We have put some more information here:
| Month | Degrees Celsius |
|---|---|
| Temperature | 5 |
| High Temperature | 8 |
| Low Temperature | 6 |
| Sunshine Per Day | 3 |
Useful Links: Swansea Weather: Average Weather & Yearly Climate