Monthly climate guide
Cardiff weather in August
With highs near 20°C (67°F) and lows around 13°C (55°F), August feels mild in Cardiff. Rainfall averages about 96 mm (wet) and the sky is often cloudy. Daytime highs are about the same as July and 2°C warmer than September.
What stands out in August
- Just 110 km apart, but Cardiff runs about 2°C warmer than Tenby this month.
- Only one month is warmer in Cardiff than August.
- Seasonally, August counts as late summer in Cardiff.
Avg high
20°C
67°F
Avg low
13°C
55°F
Rainfall
96 mm
wet
Humidity
84%
relative
Sky
74%
cloud · often cloudy
Cardiff weather by month
Show the monthly averages as a table
| Month | Avg high | Avg low | Rain | Humidity | Cloud cover |
|---|---|---|---|---|---|
| January | 7°C / 45°F | 3°C / 38°F | 97 mm | 93% | 80% |
| February | 8°C / 46°F | 3°C / 37°F | 77 mm | 91% | 79% |
| March | 9°C / 49°F | 3°C / 38°F | 68 mm | 89% | 74% |
| April | 12°C / 54°F | 5°C / 41°F | 56 mm | 85% | 69% |
| May | 15°C / 60°F | 8°C / 46°F | 62 mm | 82% | 68% |
| June | 18°C / 64°F | 11°C / 52°F | 83 mm | 82% | 71% |
| July | 20°C / 68°F | 13°C / 55°F | 66 mm | 81% | 66% |
| August | 20°C / 67°F | 13°C / 55°F | 96 mm | 84% | 74% |
| September | 18°C / 64°F | 11°C / 52°F | 73 mm | 85% | 69% |
| October | 14°C / 58°F | 9°C / 48°F | 98 mm | 89% | 76% |
| November | 10°C / 51°F | 6°C / 42°F | 104 mm | 92% | 80% |
| December | 9°C / 48°F | 5°C / 41°F | 124 mm | 93% | 83% |
What to pack for August
- T-shirts plus a light layer for the evening
- Comfortable trainers or sandals for long walks
- A compact umbrella or packable rain jacket
- Water-resistant shoes
Is August a good time to visit Cardiff?
Compare the months in the chart above to find your ideal window.
Best time to visit Cardiff →Other United Kingdom cities in August
Cite or embed this data
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Cardiff weather in August. WeatherCompare, 2026 (NASA POWER / ERA5, 2011–2020 monthly averages). https://weathercompare.eu/weather/uk/cardiff/august
<a href="https://weathercompare.eu/weather/uk/cardiff/august">Cardiff weather in August</a> (WeatherCompare)
<iframe src="https://weathercompare.eu/embed/uk/cardiff" width="300" height="160" style="border:0;border-radius:12px" loading="lazy" title="Cardiff weather in August"></iframe> <p style="font-size:12px"><a href="https://weathercompare.eu/weather/uk/cardiff/august">Cardiff weather in August</a> – WeatherCompare</p>
Cardiff in August: quick answers
Is August a good time to visit Cardiff?
August is one of the wetter months in Cardiff, with about 96 mm of rain. You can still go: pack a rain jacket and keep plans flexible.
How warm is Cardiff in August?
Average highs are about 20°C (67°F) and average lows about 13°C (55°F), based on 10 years of daily data.
Does it rain a lot in Cardiff in August?
Cardiff typically gets around 96 mm of rain in August — wet.
Figures are long-term averages for the area around Cardiff (NASA POWER / ERA5, 2011–2020), not a forecast for a specific year. For upcoming days, see the live multi-source forecast.