Lisbon in August (2027): Weather, Prices, Beaches & Things to Do

⭐ Best-value August window, based on our hotel sample: weeknights from 16 August to the end of the month. Weeknight medians were about €183 on 18 August and €175 on 25 August, the lowest of the summer we sampled. This is a price observation, not a weather claim; climate normals are broadly similar across August.

ℹ️ These are our editorial assessments of how August conditions affect each part of a trip, not review scores. Weather figures are climate normals from IPMA, Portugal's weather service, for 1991 to 2020.

💰 August 2027 hotel rates in our sample (central Lisbon, 4-star):
1 to 15 August: weeknights ~€186–187, Saturdays ~€196–197 · 16 to 31 August: weeknights ~€175–183, Saturdays ~€185–190
From a sample of 112 to 125 four-star hotels within 2 km of Baixa, quoted on 2 October 2026 for one night for two adults, room only, before taxes, on eight August 2027 dates including the Assumption weekend. Lisbon's tourist tax of €4 per person per night (maximum seven nights) is added on top. Rates change daily, so check live prices for your dates.

August is Lisbon's beach month. It is the hottest month of the year, almost always dry, and the Atlantic is at its warmest, so days that start with a morning in Alfama can end in the sea at Carcavelos or Costa da Caparica. Evenings are long and warm, and the river is the coolest place in the city on a hot afternoon.

The honest tradeoffs are heat and crowds. Afternoons on the hills can be punishing during a heatwave, and the beaches and main sights are at their busiest. The good news, in our sample, is price: August was cheaper than July, and late August was the cheapest stretch of the summer. We would book August for the beach and the river, aim for the second half if price matters, and keep sightseeing for the cooler hours.

Temperature

IPMA's 1991 to 2020 climate normals put the August average high at about 29°C and the low at about 19°C, marginally warmer than July, which makes it the hottest month on average. Most days are hot rather than extreme, but heatwaves happen; the highest August temperature in the IPMA record for Lisbon is 43.3°C.

Rain Pattern

August is effectively dry, with about 5 mm of rain on roughly 1 days. You can plan outdoor days without a wet-weather fallback.

Daylight and Outdoor Conditions

Sunrise moves from about 06:37 to about 07:03 across the month, and sunset from about 20:48 to about 20:10, so evenings shorten noticeably by the end of August. With around 340 hours of sunshine, the pattern is the same as July: comfortable mornings, hot early afternoons and long, warm evenings.

August prices in our sample were lower than July's and fell steadily through the month, while crowds stayed at summer levels.

1 to 15 August: high summer and the Assumption

Weeknight medians were about €186 to €187 and Saturdays about €196 to €197, including Saturday 14 August, the eve of the Assumption holiday. The beaches and the main sights are at their busiest.

16 to 31 August: the summer's cheapest stretch

Weeknight medians fell to about €183 on 18 August and €175 on 25 August, and Saturdays to about €185 to €190. Most people do not realise that late August was the cheapest part of the summer in our sample, about €15 to €25 a night below early July weeknights, with the sea at its warmest. Remember the tourist tax of €4 per person per night on top of the room rate.

The warmest sea of the year

The Atlantic off Lisbon averages about 19.6°C in August, with highs of around 22°C, and seatemperature.org describes it as mild. Together with September, it is the best time of year for swimming. It is still the Atlantic, though: cooler than the Mediterranean, with real waves and currents.

Which beaches

The beaches along the Cascais line, from Carcavelos to Cascais, are reachable by the suburban train from Cais do Sodré. Carcavelos is long and sandy with surf; the beaches closer to Cascais are smaller and more sheltered. Costa da Caparica, across the river to the south, has kilometres of Atlantic sand. In 2026, the lifeguarded season ran to 30 September at both, so August falls well inside it; always swim at lifeguarded beaches and follow the flags.

Jazz em Agosto

The Gulbenkian Foundation's Jazz em Agosto festival usually takes place in late July and August in the foundation's gardens. The 2027 programme had not been published when we checked, so confirm the dates before you plan around it.

Our take: in August, a beach morning or late afternoon plus an evening in the city is a better day than trying to sightsee through the heat. Our Lisbon surf lessons guide covers the beaches in more detail, and our Lisbon boat tours guide covers the cooler way to see the city from the river.

August's downsides come with peak summer.

Midday sightseeing during a heatwave

Alfama, Graça and Bairro Alto are steep, and August heatwaves can push temperatures far above the 29°C average. Climb in the morning or evening, carry water, and keep the middle of the day for the beach, the river or indoor sights.

Inland day trips on the hottest days

Fátima, Óbidos and the interior are hotter than the coast, and the UK Foreign Office flags wildfire risk in Portugal from April to October. Fires affect forested inland areas rather than Lisbon itself, but they can close roads, so check conditions before a long day trip.

Quiet sightseeing

The main sights, Tram 28 and the beaches are at their busiest. Book timed tickets, start early, and keep an eye on your bag in crowds; our is Lisbon safe guide covers the pickpocket advice.

• A beach day by train: the suburban line from Cais do Sodré follows the coast to Carcavelos and Cascais.
• The Oceanário in the heat of the day: one of the city's biggest indoor attractions, in Parque das Nações by the river.
• The Gulbenkian gardens: shade and water in the middle of the city, next to a major art museum.
• MEO Kalorama: the music festival returns to Parque da Bela Vista on the last weekend of August 2027; exact dates and line-up had not been announced when we checked.
• Sunset at the miradouros: sunset moves from about 20:48 to 20:10, so the viewpoints work after dinner early in the month and before it by the end.

• Choose late August if you can: weeknight medians in our sample fell to about €175 on 25 August.
• Sightsee early and late: do the hills before noon or after 18:00, and keep the hottest hours for the beach, the river or indoors.
• Swim at lifeguarded beaches: the sea is at its warmest, but it is still the Atlantic, with waves and currents.
• Check conditions before inland day trips: heatwaves and wildfires can affect roads away from the coast.
• Book Sintra's timed tickets well ahead: August is one of the busiest months for the palaces.
• Carry water and sun cream: August sun on the hills is strong.
• Plan Belém for a day other than Monday: Jerónimos Monastery is closed on Mondays.
• Budget for the tourist tax: Lisbon adds €4 per person per night, up to seven nights, on top of the room rate.
• Visiting at a different time of year? Our Lisbon in July guide covers the month before, with NOS Alive and the sunniest weather of the year, our Lisbon in June guide covers Santo António, and our Lisbon in September guide covers the warmest sea of the year and the grape harvest.