August is the hottest month at about 29°C, and the month Lisbon empties of Lisboetas. They go to the Algarve and the north; the visitors stay. The result is a city at peak price and peak crowding in the centre, with a strangely quiet residential half and a number of good neighbourhood restaurants closed for the month.
The weather, precisely
Hot, dry and reliable: 29°C average, about 6 mm of rain across the month, and the nortada still doing its work on the coast most afternoons. Heatwaves push the city past 38°C for days at a time, and the Alentejo behind it much higher again.
Nights stay at about 19°C, which is comfortable – but note that many older Lisbon apartments and guesthouses have no air conditioning, and a top-floor room under a tiled roof in August is genuinely unpleasant. Check before booking.
The August closures
Portuguese summer holidays concentrate in August, and it shows in the everyday city rather than the tourist one:
- Family-run tascas and neighbourhood restaurants close, often for two to four weeks, with a handwritten sign in the window. The place you read about may simply not be open.
- Some small shops and bakeries do the same.
- Monuments, museums and tourist restaurants run normally and are busier than ever.
- Check current opening hours the same week rather than trusting a review from March.
Assumption Day, 15 August
Assunção de Nossa Senhora is a national public holiday, falling on a Sunday in 2027. Banks and offices close, many shops do too, and it is a peak day on the beaches and the roads out of the city. Coastal traffic on the Ponte 25 de Abril and the Ponte Vasco da Gama is heavy that weekend.
What August is good for
- The beaches, at the Atlantic’s warmest 19°C. Carcavelos and the Costa da Caparica are the easy ones by train and ferry; Sesimbra and the Arrábida coast, south of the Tagus, have the clearest water in the region and are worth the trip.
- Jazz em Agosto at the Gulbenkian – concerts in the foundation’s open-air amphitheatre and gardens, usually in the first half of the month.
- Evenings. Lisbon in August lives from seven at night onwards, and the miradouros, the riverside at Cais do Sodré and the Tagus ferries are what the month is for.
- Sunset from the water. The ordinary commuter ferry to Cacilhas costs a couple of euros and gives the best view of the city there is.
What not to do
Do not attempt Sintra, Belém and central Lisbon on foot in the middle of an August day. The calçada radiates heat, the hills are unforgiving and the queues are unshaded. Mornings and evenings only; midday belongs to the Gulbenkian’s air conditioning or a beach.
Prices and crowds
Peak on both counts. Book monuments, Sintra entry and any accommodation well ahead. August and July are the two most expensive months of the Lisbon year. See what a trip to Portugal costs.
What to pack
Light clothing, a hat, high-factor sunscreen and sunglasses. A light layer for the evening nortada. Comfortable shoes with grip. A refillable bottle – Lisbon tap water is safe and there are public fountains. Swimwear, and a windbreak if you are heading to Guincho.
The August 2027 calendar
- Through August – the hottest month at about 29°C, with heatwaves possible past 38°C; roughly 6 mm of rain.
- Through August – Portuguese summer holidays; many family restaurants and small shops closed for two to four weeks.
- Usually the first half of August – Jazz em Agosto at the Gulbenkian.
- Sunday 15 August – Assumption Day, a national public holiday; heavy traffic on the bridges and packed beaches.
- Through August – the Atlantic at its warmest, about 19°C; sardine season continuing.
- Through August – peak prices and peak queues at Belém and Sintra.
Read alongside
- Lisbon in July – a degree cooler, with the city still full of locals.
- Lisbon in September – the same warm sea, far fewer people.
- Lisbon in June – cooler, and the Santo António festivals.
- Best time to visit Lisbon – all twelve months compared.
- Lisbon itinerary – how to structure a hot day.
- Lisbon travel guide – the neighbourhoods and how they differ.
- Trip to Portugal cost – peak-season numbers.
Frequently asked
How hot is Lisbon in August?
About 29°C by day and 19°C at night, the hottest month, with heatwaves that can exceed 38°C. The coast stays cooler thanks to the afternoon nortada.
Are restaurants closed in Lisbon in August?
Many family-run tascas and neighbourhood places close for two to four weeks while the owners take their summer holiday. Tourist-facing restaurants and all the monuments run normally. Check hours the same week.
Do Lisbon apartments have air conditioning?
Often not, especially older buildings and guesthouses. A top-floor room under a tiled roof in August is genuinely uncomfortable – confirm before booking.
Is 15 August a holiday in Portugal?
Yes, Assumption Day is a national public holiday. In 2027 it falls on a Sunday, making it a peak beach and traffic day.
How warm is the sea in Lisbon in August?
About 19°C – its annual peak, and still bracing. The Atlantic here never behaves like the Mediterranean.
Which beaches are best near Lisbon in August?
Carcavelos and the Costa da Caparica are easiest by train and ferry. Sesimbra and the Arrábida coast south of the Tagus have the clearest water. Guincho is beautiful but windy.
Is August a bad time to visit Lisbon?
It is the hottest, most expensive and most crowded month, with part of the everyday city shut. If you want beaches and long evenings it works; for sightseeing, May or September are far better.
What is Jazz em Agosto?
A jazz festival held at the Gulbenkian Foundation, usually in the first half of August, with concerts in the open-air amphitheatre and gardens.
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Written by
John Morrison is the founder and lead travel writer at Packzup. Over the past decade he has explored destinations across Africa, the Americas, Asia, Europe, the Middle East, and Oceania — always self-funded, never on a press trip.
