Cardiff, United Kingdom Climate & Monthly Averages
The climate of Cardiff
Cardiff has an oceanic climate. Average highs run from 46°F (8°C) in January to 69°F (20°C) in July, and the city records roughly 171 days of measurable precipitation a year.
Climate quick facts
- Hottest month: July - highs near 69°F (20°C)
- Coldest month: January - highs near 46°F (8°C)
- Decade extremes (2015-2024): 91°F (33°C) high · 22°F (-6°C) low
- Wettest month: December (17 rainy days) · Sunniest: June (11.7 h sun/day)
- Climate type: oceanic
- Annual swing: 12°C between the average warmest and coolest month · day to night: 6°C
- Snow: about 2 days a year
- Average humidity: 82%
Temperatures through the year
Snowfall is rare but not unheard of. January sits at the other end of the year: 46°F (8°C) by day, 37°F (3°C) at night. Warmth peaks in July: highs of 69°F (20°C), lows of 56°F (13°C). The wettest month is December (5.6 inches (143 mm) across 17 days) and the driest June.
Rain, sun and snow
Days and nights are about 6°C apart on average - narrower than all but 10% of the 3496 cities in our dataset. Sunshine averages 7.7 hours a day over the year - duller than about 89% of the cities we track, peaking in June at 11.7 hours. Relative humidity averages 82% across the year, more humid than 92% of the 3496 cities in our dataset. The gridded 2015-2024 daily record for this location tops out at 91°F (33°C) and bottoms at 22°F (-6°C) - decade extremes, not all-time station records.
How Cardiff compares
- Cardiff sits close to the middle of our dataset on most measures: 52°F (11°C) as an annual average, 47.8 inches (1215 mm) of precipitation and 7.7 hours of sun a day.
Ranked against every city in our dataset, each measured on the same ten-year window.
Monthly climate table
| Month | High | Low | Rain days | Precipitation | Sunshine | Humidity |
|---|---|---|---|---|---|---|
| January | 46° | 37° | 15 | 4.0 in | 4.1 h/day | 87% |
| February | 48° | 38° | 14 | 4.2 in | 5.3 h/day | 84% |
| March | 50° | 39° | 16 | 4.2 in | 6.9 h/day | 81% |
| April | 55° | 41° | 11 | 2.6 in | 9.8 h/day | 76% |
| May | 61° | 47° | 12 | 3.3 in | 11.1 h/day | 77% |
| June | 66° | 53° | 12 | 2.6 in | 11.7 h/day | 76% |
| July | 69° | 56° | 15 | 3.4 in | 11.4 h/day | 77% |
| August | 68° | 56° | 15 | 4.0 in | 10.0 h/day | 80% |
| September | 64° | 53° | 13 | 4.1 in | 8.5 h/day | 82% |
| October | 58° | 48° | 16 | 5.4 in | 6.3 h/day | 84% |
| November | 51° | 43° | 15 | 4.4 in | 4.4 h/day | 87% |
| December | 49° | 41° | 17 | 5.6 in | 3.3 h/day | 89% |
Cardiff month by month
Cardiff weather in January
January brings highs around 46°F (8°C), lows near 37°F (3°C), about 15 wet days - typically the coldest month of the year in Cardiff.
Cardiff weather in February
February brings highs around 48°F (9°C), lows near 38°F (3°C), about 14 wet days.
Cardiff weather in March
March brings highs around 50°F (10°C), lows near 39°F (4°C), about 16 wet days.
Cardiff weather in April
April brings highs around 55°F (13°C), lows near 41°F (5°C), about 11 wet days.
Cardiff weather in May
May brings highs around 61°F (16°C), lows near 47°F (9°C), about 12 wet days.
Cardiff weather in June
June brings highs around 66°F (19°C), lows near 53°F (12°C), about 12 wet days - typically the driest month and the sunniest month of the year in Cardiff.
Cardiff weather in July
July brings highs around 69°F (20°C), lows near 56°F (13°C), about 15 wet days - typically the hottest month of the year in Cardiff.
Cardiff weather in August
August brings highs around 68°F (20°C), lows near 56°F (13°C), about 15 wet days.
Cardiff weather in September
September brings highs around 64°F (18°C), lows near 53°F (12°C), about 13 wet days.
Cardiff weather in October
October brings highs around 58°F (15°C), lows near 48°F (9°C), about 16 wet days.
Cardiff weather in November
November brings highs around 51°F (11°C), lows near 43°F (6°C), about 15 wet days.
Cardiff weather in December
December brings highs around 49°F (9°C), lows near 41°F (5°C), about 17 wet days - typically the wettest month of the year in Cardiff.
Seasons in Cardiff
Spring (March through May)
Through spring, Cardiff stays on the cool side of mild: 55°F (13°C) by day, 43°F (6°C) after dark, and rain falls on around 39 of the 90 days.
Summer (June through August)
Summer in Cardiff stays on the cool side of mild, with daytime highs averaging 67°F (20°C) and nights around 55°F (13°C); rain falls on around 42 of the 90 days. Daylight is generous - around 11.0 hours of sun a day.
Fall (September through November)
Fall in Cardiff is crisp but comfortable, with daytime highs averaging 58°F (14°C) and nights around 48°F (9°C); rain falls on around 44 of the 90 days.
Winter (December through February)
Through winter, Cardiff is brisk and cold: 47°F (9°C) by day, 38°F (4°C) after dark, and rain falls on around 46 of the 90 days.
Climate questions, answered
How warm is Cardiff on average?
How much sun does Cardiff get?
What should I wear in Cardiff?
How much do temperatures drop at night in Cardiff?
How hot does Cardiff get in summer?
Best time to visit Cardiff
The best time to visit Cardiff is generally April to September, when warm days, manageable rainfall and plenty of daylight line up. Daytime temperatures in that window sit near 64°F (18°C), with rain on about 13 days a month. For the same question asked the other way round, see where else is warm in April.
Pack for Cardiff with a warm jacket and layers for the cooler season and proper waterproofs rather than an umbrella - wet days are the norm here. Note the gap between afternoon and night: July pairs 69°F (20°C) with 56°F (13°C).
Cardiff temperature records (2015-2024)
Derived from ERA5 reanalysis data, 2015–2024. Official station records may differ.