Swansea, United Kingdom Climate & Monthly Averages
Swansea has an oceanic climate. July is the hottest month, averaging 67° by day; January is the coldest at 47°.
How weather changes through the year in Swansea
Weather in Swansea follows a oceanic pattern. The warmest and coolest months, July and January, average 67°F (19°C) and 47°F (8°C) by day; nights in those months run 56°F (13°C) and 38°F (4°C).
Swansea climate quick facts
- Hottest month: July - highs near 67°F (19°C)
- Coldest month: January - highs near 47°F (8°C)
- Decade extremes (2015-2024): 90°F (32°C) high · 22°F (-5°C) low
- Wettest month: December (19 rainy days) · Sunniest: June (11.0 h sun/day)
- Climate type: oceanic
- Annual swing: 11°C between the average warmest and coolest month · day to night: 5°C
- Snow: about 2 days a year
- Average humidity: 81%
Temperatures, rain and sunshine
Sunshine averages 7.3 hours a day over the year - duller than all but 4% of the 3496 cities in our dataset, peaking in June at 11.0 hours. January bottoms out at 47°F (8°C) in daylight, 38°F (4°C) after dark. July is the warm end of the year, averaging 67°F (19°C) by day and 56°F (13°C) overnight. Across the gridded 2015-2024 daily record, the highest daily maximum for this location was 90°F (32°C) and the lowest daily minimum 22°F (-5°C).
Snowfall is rare but not unheard of.
Days and nights are about 5°C apart on average - narrower than all but 5% of the 3496 cities in our dataset.
Where Swansea sits among other climates
- Rain or snow reaches the ground on 190 days a year - more wet days than 89% of the 3496 cities we track.
- Relative humidity averages 81% - more humid than 88% of the 3496 cities we track.
These comparisons use the same ten-year window for every city in the dataset.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Daylight | Wet-day chance | Humidity |
|---|---|---|---|---|---|---|---|---|
| January | 47° | 38° | 16 | 5.2 in | 3.8 h/day | 8.3 h | 50% | 85% |
| February | 48° | 39° | 15 | 4.8 in | 5.0 h/day | 9.9 h | 55% | 83% |
| March | 50° | 40° | 17 | 4.9 in | 6.8 h/day | 11.7 h | 55% | 81% |
| April | 54° | 42° | 12 | 2.7 in | 9.5 h/day | 13.8 h | 40% | 76% |
| May | 60° | 48° | 14 | 3.6 in | 10.7 h/day | 15.6 h | 45% | 78% |
| June | 65° | 53° | 14 | 3.4 in | 11.0 h/day | 16.6 h | 46% | 78% |
| July | 67° | 56° | 17 | 4.4 in | 10.4 h/day | 16.2 h | 54% | 79% |
| August | 66° | 56° | 18 | 5.0 in | 9.4 h/day | 14.6 h | 58% | 81% |
| September | 64° | 53° | 15 | 5.2 in | 8.0 h/day | 12.6 h | 50% | 82% |
| October | 58° | 50° | 17 | 6.5 in | 6.0 h/day | 10.5 h | 55% | 83% |
| November | 52° | 44° | 17 | 5.6 in | 4.2 h/day | 8.7 h | 57% | 84% |
| December | 49° | 42° | 19 | 7.5 in | 3.1 h/day | 7.8 h | 60% | 87% |
Swansea month by month
Each card shows the average high and low. The bar places that month between Swansea's coldest night and warmest afternoon.
January
- Rain
- 16 days
- Sunshine
- 3.8 h
- Daylight
- 8.3 h
February
- Rain
- 15 days
- Sunshine
- 5.0 h
- Daylight
- 9.9 h
March
- Rain
- 17 days
- Sunshine
- 6.8 h
- Daylight
- 11.7 h
April
- Rain
- 12 days
- Sunshine
- 9.5 h
- Daylight
- 13.8 h
May
- Rain
- 14 days
- Sunshine
- 10.7 h
- Daylight
- 15.6 h
June
- Rain
- 14 days
- Sunshine
- 11.0 h
- Daylight
- 16.6 h
July
- Rain
- 17 days
- Sunshine
- 10.4 h
- Daylight
- 16.2 h
August
- Rain
- 18 days
- Sunshine
- 9.4 h
- Daylight
- 14.6 h
September
- Rain
- 15 days
- Sunshine
- 8.0 h
- Daylight
- 12.6 h
October
- Rain
- 17 days
- Sunshine
- 6.0 h
- Daylight
- 10.5 h
November
- Rain
- 17 days
- Sunshine
- 4.2 h
- Daylight
- 8.7 h
December
- Rain
- 19 days
- Sunshine
- 3.1 h
- Daylight
- 7.8 h
Looking for warmer alternatives? Browse warm places by month, or compare Swansea's coolest part of the year: January, February, December.
A season-by-season guide to Swansea
Spring (March through May)
Spring stays on the cool side of mild here - highs near 55°F (13°C), nights near 43°F (6°C), and rain falls on around 43 of the 90 days.
Summer (June through August)
Summer is crisp but comfortable here - highs near 66°F (19°C), nights near 55°F (13°C), and rain falls on around 48 of the 90 days. Daylight is generous - around 10.3 hours of sun a day.
Fall (September through November)
Fall is crisp but comfortable here - highs near 58°F (14°C), nights near 49°F (9°C), and rain falls on around 49 of the 90 days.
Winter (December through February)
Winter stays firmly cold here - highs near 48°F (9°C), nights near 40°F (4°C), and rain falls on around 50 of the 90 days.
Questions people ask about Swansea's climate
How warm is Swansea on average?
Is Swansea a wet city?
How much do temperatures drop at night in Swansea?
How much sun does Swansea get?
The most useful weather window for Swansea
Best time to visit Swansea
April to June and September is the sweet spot for Swansea - warm days, manageable rainfall and plenty of daylight line up. Expect 61°F (16°C) in the afternoon and around 14 days of rain in a typical month of it. For the same question asked the other way round, see where else is warm in April.
What to pack
Pack for Swansea with a warm jacket and layers for the cooler season and proper waterproofs rather than an umbrella - wet days are the norm here. July nights average 56°F (13°C), so evenings rarely match the afternoons.
Swansea temperature extremes in the 2015–2024 dataset
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ. Need another precipitation unit? Use the rainfall converter.