How hot is Lisbon in July and August?
Quick answer: according to IPMA, the Portuguese weather institute, the average daily high in Lisbon is 28.3 °C (83 °F) in July and 29.0 °C (84 °F) in August (climate normals 1991 to 2020, station Lisboa / Gago Coutinho). August averages 10.7 days at 30 °C or more and 2.8 days at 35 °C or more; the station record is 44.0 °C on 4 August 2018. Nights usually cool to around 18 °C, but on about 4 to 6 nights a month in high summer they stay above 20 °C, mostly during heatwaves. A west facing or top floor flat holds the heat for hours after sunset. More detail for travellers in Lisbon in August.
| Month | Average high | Days at 30 °C or more | Days at 35 °C or more |
|---|---|---|---|
| June | 26.1 °C (79 °F) | 6.2 | 0.9 |
| July | 28.3 °C (83 °F) | 9.1 | 2.5 |
| August | 29.0 °C (84 °F) | 10.7 | 2.8 |
| September | 26.8 °C (80 °F) | 6.5 | 0.6 |
Source: IPMA climate normals 1991 to 2020, Lisboa / Gago Coutinho. Days are monthly averages.
Does my Lisbon Airbnb have air conditioning?
Often not. Air conditioning is not standard in Lisbon, especially in the older buildings of the historic neighbourhoods (Alfama, Mouraria, Bairro Alto, Baixa). Before you book or arrive, check the listing's amenities for "air conditioning" specifically, not just "fan", which won't cope in an apartment at 30 °C. If the listing doesn't mention AC, assume it has none.
How to keep your apartment cool without AC
A few things help: close shutters and curtains during the day to block the sun, air the place out at dawn and at night when it cools, use fans and stay hydrated. But in the middle of a heatwave, in an apartment with no insulation, this is rarely enough to sleep well, and that is where a temporary portable air conditioner comes in.
Too hot to sleep in Lisbon: what actually helps?
Most Lisbon flats heat up during the afternoon and release that heat at night, so the bedroom is often warmer at midnight than the street. What works, in order of effect: keep shutters and curtains closed on the sunny side from the morning, because blocked sun is heat that never gets in. After sunset, open windows on opposite sides of the flat to get a through draught, and put a fan in a window blowing out rather than at your bed. Sleep in the coolest room, which is usually the one facing north or the inner courtyard, not the top floor. A lukewarm shower right before bed lowers your skin temperature better than a cold one. A damp sheet or a frozen water bottle near the fan gives brief relief, not a cool room. On nights that stay above 20 °C these tricks reach their limit, and a portable air conditioner in the bedroom is the only thing that brings the room down to a temperature you can sleep at.
What should you do in a Lisbon heatwave?
Follow the IPMA warnings: yellow, orange and red heat warnings for the Lisbon district are published on ipma.pt and in the IPMA app, usually a day or two ahead. During the warning, plan outdoor walking for before 11:00 and after 18:00, and spend the middle of the day somewhere cool: museums, air conditioned shopping centres, churches with thick walls, or by the river where the breeze helps. Drink water before you are thirsty, keep to the shade on the steep streets of Alfama and Graça, and check on older neighbours or travel companions. If you or someone with you feels unwell from the heat, the national health line SNS 24 (808 24 24 24) gives advice by phone, and 112 is the emergency number. At home, keep the flat closed during the day and cool the bedroom before night falls, not after.
My Lisbon apartment has no air conditioning: what are my options?
You have three realistic options. A fan is cheap and helps up to about 28 °C indoors, then it only moves warm air around. A fixed split unit is the best long term answer for an owner, but it needs an installer, often the building's permission and, in the historic centre, approval for the outdoor unit, so it is not a solution for this week or for a tenant. A portable air conditioner sits in the room, plugs into a normal socket and vents through the window with a sealing kit: no drilling, nothing fixed to the facade, and no landlord permission needed. Buying one makes sense if you will use it every summer and have space to store it; for a visit, a single heatwave or a short lease, renting is simpler. AC Rental Lisbon delivers one the same day when you confirm before 16:00, from €40 a day or €210 a week, plus €25 for delivery, setup and collection and a refundable €100 deposit.
The AC Rental Lisbon solution
You don't need to buy or install anything. We deliver a 9,000 BTU portable air conditioner straight to your Airbnb or hotel, the same day, with the window sealing kit included: no drilling, no works, no landlord permission needed. Perfect for a stay of 3 days to 3 weeks.
Renting an air conditioner for your stay
Renting makes more sense than buying when you only need it for your trip. We deliver across Lisbon and Greater Lisbon, including Belém, Alfama, Baixa, Chiado, Príncipe Real, Cascais, Oeiras and Estoril. From €40/day, €210/week or €450/month, with a refundable €100 deposit. Confirm before 4pm and, subject to availability, we deliver the same day. See pricing or message us on WhatsApp.
Frequently asked questions
Is August too hot in Lisbon?
August is the hottest month, with an average high of 29 °C and about 3 days above 35 °C (IPMA normals). It is perfectly visitable, but accommodation without air conditioning can be uncomfortable, especially at night.
Do Lisbon Airbnbs have air conditioning?
Many don't, especially in the older buildings of the historic neighbourhoods. Always check the listing amenities before booking; if it doesn't mention air conditioning, assume it has none.
Can I rent an air conditioner for just a few days?
Yes. We rent by the day (from €40/day), by the week (€210) or by the month (€450), ideal for the exact length of your stay.
Can you deliver to my Airbnb?
Yes, we deliver straight to your accommodation across Lisbon and Greater Lisbon, the same day if you confirm before 4pm, with the window kit included and no fixed installation.
What can I do if it is too hot to sleep in Lisbon?
Close shutters on the sunny side by day, create a through draught after sunset, sleep in the coolest room and use a fan blowing out of the window. When nights stay above 20 °C, a portable air conditioner in the bedroom is what makes sleep possible.
Can I use a portable air conditioner in a rented flat in Lisbon?
Yes. A portable unit plugs into a normal socket and vents through the window with a sealing kit, so nothing is drilled or fixed to the building and no landlord permission is needed.