Cardiff weather in July
Temperature, sea and sunshine in July: long-term averages from 30 years of weather data, not a forecast.
Holiday weather in July
Good
Best time to visit: June – September
What is the weather like in Cardiff in July?
In July, Cardiff is mild: daytime highs average 20 °C, and nights cool down to about 14 °C. The sea averages 17.6 °C – bracing, so a wetsuit helps for longer swims. The sun shines for around 7 hours a day. Rain is frequent, with about 11 rainy days and 64 mm in total. All in all, July is a good month for a holiday in Cardiff.
July compared
How the weather changes from June to August. Tap a month to open it.
More details for July
- Daylight
- 16 h 13 min05:12 – 21:25
- UV index
- 7 · highclear sky, noon (estimate)All months
- Muggy days
- 0 daysdew point 18 °C or moreAll months
- Wind
- 22 km/haverage daily peakAll months
- Cloud cover
- 63 %on averageAll months
- Hot days
- 0 days30 °C or more
- Time zone
- UTC+1Europe/London
How the score comes together
- Temperatureweight 50 %100 %
- Sunshineweight 20 %62 %
- Few rainy daysweight 30 %48 %
Each factor is rated from 0 to 100 % and weighted for the travel style “City break”.
What to pack in July
- Wetsuit for longer swims
- Sunscreen
- Sunglasses & sun hat
- A jumper for the evenings
- Rain jacket or umbrella
Cardiff in July: quick answers
Is Cardiff hot in July?
No. In July, Cardiff is mild: daytime highs average 20 °C and nights drop to about 14 °C.
Can you swim in Cardiff in July?
Only if you don't mind cold water: in July the sea averages just 17.6 °C. Comfortable swimming temperatures are not reached at any time of year.
Does it rain much in Cardiff in July?
Rain is frequent, with about 11 rainy days and 64 mm in total.
Cardiff month by month
The whole year in CardiffAll destinations: United KingdomWhere to go in JulySea temperature in July
Climate averages 1996–2025, not a forecast. Data: Copernicus ERA5 / ERA5-Land via Open-Meteo.com (CC BY 4.0), NOAA OISST, WMO 1991–2020 (NOAA NCEI), GeoNames (CC BY 4.0). Sources & licences