Monthly weather averages & travel planning

Europe › 🇪🇸 Spain › Barcelona
Updated: March 2026
August is a excellent time to visit Barcelona (8/10). With 12 daily sunshine hours and only 7 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 4th sunniest of the year in Barcelona. Beach and outdoor-focused visitors will find August ideal, though hotel prices reflect demand and popular sites get crowded by mid-morning. La Merce Festival takes place this month, adding cultural value for those planning around it. The main practical note: Barcelona's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: book accommodation at least 6-8 weeks ahead, as popular hotels fill quickly during August. Purchasing skip-the-line tickets for major attractions in advance saves meaningful time. If you have flexibility, arriving a few days before or after peak weekends reduces both crowds and prices noticeably.
Based on 30-year climate normals (1991 to 2020), August in Barcelona averages 28°C by day and 21°C overnight, a range that places it firmly in the warmer tier of the annual calendar. The month records approximately 12 sunshine hours per day and 40mm of total rainfall across 7 wet days, giving it a sunshine-to-rain ratio that is decidedly favourable for outdoor travel.
28°C
82°F
Avg High
21°C
70°F
Avg Low
7 days
40 mm total
Rain Days
12h
per day avg
Sunshine
65%
Moderate
Humidity
The 7°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 65%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 9 this month, classed as high to very high. SPF 30+ sunscreen, a brim hat, and sunglasses are not optional between 10am and 4pm. Wind averages 16 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 82°F average high, 70°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Packing for Barcelona in August means dressing for 28°C days and 21°C evenings. A light cotton tee with a casual overshirt works well at 28°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 21°C, a modest 7°C drop that a light cardigan or denim jacket covers. European cobblestones reward low-profile walking shoes over flip-flops or heels, with cushioned trainers or leather walking shoes being the practical choice.
Local tip: Many of Barcelona's museums and galleries maintain cool interior temperatures regardless of outdoor conditions. A compact layer in your daypack lets you move between warm streets and chilled exhibition halls without discomfort.
Around September 24
Barcelona's biggest free festival honours the city's patron saint. Human tower competitions, giant puppet parades, free concerts at the Palau de la Musica, and fireworks.
BarcelonaBased on 28°C average highs and 7 rainy days
Barcelona's August weather is dominated by the Azores High, a semi-permanent subtropical anticyclone that blocks Atlantic rain systems from reaching the Mediterranean. As a result, August delivers reliably sunny, dry conditions with temperatures averaging 28°C. The sea moderates extreme heat and keeps overnight lows around 21°C, making the city noticeably more comfortable than inland Mediterranean destinations. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Barcelona in August
August ranks 4th sunniest of the year in Barcelona, with an average 12 daily sunshine hours. The driest months are July, January, and February. August is the hottest month (28°C avg high); January is the coolest (13°C). From here, temperatures fall 4°C into September. Compared to last month (July: 27°C high, 5 rain days), August is warmer and wetter. August sits in the middle of the annual sunshine ranking for Barcelona, offering a reasonable balance of good weather and manageable crowds.
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 13°C | 5°C | 6 | 8h | View |
| February | 13°C | 5°C | 6 | 9h | View |
| March | 16°C | 7°C | 7 | 10h | View |
| April | 17°C | 10°C | 9 | 11h | View |
| May | 21°C | 13°C | 7 | 12h | View |
| June | 25°C | 17°C | 6 | 13h | View |
| July | 27°C | 20°C | 5 | 13h | View |
| August | 28°C | 21°C | 7 | 12h | View |
| September | 24°C | 18°C | 11 | 10h | View |
| October | 21°C | 14°C | 10 | 9h | View |
| November | 16°C | 9°C | 8 | 8h | View |
| December | 13°C | 6°C | 6 | 7h | View |
January
6 rain days, 8h sun
February
6 rain days, 9h sun
March
7 rain days, 10h sun
April
9 rain days, 11h sun
May
7 rain days, 12h sun
June
6 rain days, 13h sun
July
5 rain days, 13h sun
August
7 rain days, 12h sun
September
11 rain days, 10h sun
October
10 rain days, 9h sun
November
8 rain days, 8h sun
December
6 rain days, 7h sun
Cities within 500 km with comparable weather conditions
Data Sources for Barcelona
Climate normals represent 30-year averages (1991-2020). Individual years may vary.