Weather in Barcelona in August

How August compares

August is the 1st warmest month of the year in Barcelona and ranks 99th of 134 destinations we compare for August - see where else is hot in August. Within Spain it is 65th of 87 (Spain in August). Against London's average high of 21.4°C in August, Barcelona is 6.0°C warmer by day and 7.3°C warmer at night.

Daytime and night-time in August

The typical August day in Barcelona peaks at 27.4°C, but that is an average: the warmest 10% of days reach 30.2°C or more. About 85% of days top 25°C and 1 in 8 pass 30°C. Nights average 20.8°C; one night in ten drops to 18.7°C or lower, so pack a layer for evenings. Between 1991 and 2020 the hottest August day here reached 35.6°C (2010-08-27) and the coldest night 13.8°C (2002-08-11).

Rain in August

Some rain (4-8 rainy days): about 7 days with 1 mm or more, 40 mm in total. Year to year it varies a lot - the wettest August was 2002 with 116 mm, the driest 2011 with 2 mm. Humidity averages 75%.

Sea temperature in August

The sea averages 25.5°C - warm enough to swim (22°c+). Depending on the year it ranges from 24.7°C to 26.2°C. This is the warmest the sea gets here all year.

Sunshine and daylight

Around 8.3 hours of sunshine a day (estimated from cloud cover), 13.7 hours of daylight: the sun rises about 07:01 and sets about 20:51 local time in mid-August. Average cloud cover is 39%.

Is August a good time to visit Barcelona?

Yes - it is one of the better months: hot days, manageable rain and long sunny days. The best months for Barcelona on our scoring are July, June, August; months averaging 25°C or more: Jul, Aug.

Expect sustained warmth, not just occasional hot days

August is Barcelona’s warmest month, with 85% of days reaching 25°C and 12% reaching 30°C. That makes light, breathable clothing a sensible starting point, while humidity of 75% can make the warmth feel more tiring. Plan longer walks for the morning, keep midday flexible and choose accommodation where you can cool down comfortably. Average night lows of 20.8°C mean evenings are generally warm rather than a reliable break from the heat. A light layer is still useful for cooler spells, but heavy clothing is unlikely to earn its place in your luggage. If heat disrupts your sleep or limits how much you enjoy walking, August deserves some caution.

Warm swimming water, with some rain to work around

The sea is a strong reason to choose August: at an average of 25.5°C, it is warm enough for swimming without the bracing feel of cooler months. Reported year-to-year averages range from 25°C to 26°C, so warm water is a more dependable draw than completely dry weather. There are about 7 rainy days during the month, which means you should allow for wet weather rather than assume every day will suit outdoor plans. Average sunshine of about 8.3 hours a day still gives August a sunny balance overall. Pack sun protection alongside a light waterproof, and keep your swimming plans flexible. This combination suits travellers happy to mix time in the water with city walking and breaks from the heat.