Portugal's climate, region by region: the official thirty-year averages

• Official normals, 1991–2020 (IPMA): Lisbon averages 17,6 °C over the year with 794 mm of rain on 76 days; Porto 15,3 °C and 1 147 mm on 105 days; Faro 18,2 °C and 455 mm on 49 days
• Dry summers everywhere: July brings 2,6 mm in Lisbon, 0,9 mm in Faro, 16,6 mm in Porto — and 33 days a year above 30 °C in Lisbon, 88 in Beja
• Wet winters, mild on the coast, cold inland: January highs of 15 °C in Lisbon and 16 °C in Faro, but 9 °C in Bragança, which has 53 frost days a year; Guarda, at 1 019 m, is the coldest city
• Islands apart: Funchal 20 °C year-round average and never below 8,5 °C in thirty years; Ponta Delgada 18,2 °C with rain on 122 days

Portugal’s climate is Mediterranean with an Atlantic edge: hot, dry summers; mild, wet winters; and a coast that moderates both. The differences between regions are larger than the country’s size suggests — Porto gets two and a half times the rain of Faro, Bragança has frost on 53 days a year while Lisbon has none — and they decide heating bills, how a house is built and where a retiree wants to be in January. The figures below are the IPMA’s 1991–2020 climatological normals, the thirty-year averages Portugal’s weather service publishes station by station.

The map in six climates

Lisbon and the Setúbal coast. Annual mean 17,6 °C at the Lisbon observatory. January averages 15,1 °C by day and 8,6 °C at night; August 28,8 °C and 18,8 °C. Rain falls almost entirely from October to April (November 134 mm, July 2,6 mm), 794 mm in all on 76 days. The city has 33 days above 30 °C a year and about 5 above 35 °C; the record is 43,3 °C on 4 August 2018. No frost in the thirty-year record. Setúbal, across the estuary, is a degree hotter in summer (30,7 °C August highs, 56 days above 30 °C).

Porto and the Minho. The green north is green for a reason: 1 147 mm of rain a year at Porto airport on 105 days, 1 387 mm in Braga, 1 593 mm in Ponte de Lima. Summers are mild — Porto’s August high averages 24,8 °C, with 13 days above 30 °C — and winters cool and damp (January 14,0 °C by day, 6,4 °C at night, one or two frost days). The annual mean is 15,3 °C.

The Algarve. Faro has the country’s driest and sunniest mainland climate: 455 mm of rain on 49 days, 18,2 °C annual mean, July highs of 29,4 °C and January highs of 16,3 °C, 45 nights a year above 20 °C. The sea breeze keeps extremes down — 3 days above 35 °C, against 32 in the Alentejo — which is why the coast fills with Northern Europeans in winter and with everyone in August.

The Alentejo and the Tagus valley. Inland and low, Évora and Beja are the hot interior: August highs of 33,5 °C, 87–88 days a year above 30 °C and 31–32 above 35 °C, records of 45,4 °C (Évora, 4 August 2018). Rain is scarce (540 mm in Beja) and winters are cool, with a few frost nights. Santarém on the Tagus sits between Lisbon and the Alentejo: 30,8 °C July highs, 608 mm of rain.

The centre and the mountains. Coimbra is Lisbon’s climate with more rain (866 mm) and colder nights (6 frost days). Climb to Viseu (644 m) and Guarda (1 019 m) and the winters turn continental: Guarda’s January averages 7,2 °C by day and 1,5 °C at night, with 32 frost days and 964 mm of rain; Portugal’s only ski runs are in the Serra da Estrela above it.

Trás-os-Montes. Bragança, at 691 m in the north-east, has the widest range of any city: January 9,1 °C by day and 0,4 °C at night, 53 frost days, a record low of −10,2 °C — and July highs of 29,8 °C with 46 days above 30 °C. Dry for the north (784 mm).

The islands. Madeira’s Funchal averages 20,0 °C, from 20 °C highs in January to 26,8 °C in August, and has never gone below 8,5 °C in the thirty-year record; rain, 574 mm, falls mostly from October to February. The Azores are the opposite: Ponta Delgada averages 18,2 °C with almost no seasonal extremes (17,5 °C January highs, 26,0 °C August), never above 30 °C, but rain on 122 days a year and 988 mm; Flores gets 1 641 mm.

Month by month, three cities

What the numbers mean for living here

• Houses are built for summer. Stone and tile keep the heat out, not the cold in; a Lisbon flat at 8 °C outside can be colder inside than a Berlin flat at −5 °C. Ask about insulation, double glazing and heating before renting anywhere north of the Algarve; the energy certificate (class A to F) is mandatory in every listing.
• Heating is the winter cost, cooling the summer one — reversed from most of Northern Europe. Inland (Évora, Beja, the Tagus valley) air-conditioning is not optional in August; on the coast the sea breeze does the work.
• Rain comes in bursts. Porto’s 105 rain days are spread over the winter half; Lisbon’s 76 are concentrated in a few wet months, with long dry spells between. Drought years and water restrictions in the Algarve and Alentejo are part of the pattern.
• Heat waves are the risk to plan for. The August 2018 records (45,4 °C in Évora and Beja, 43,3 °C in Lisbon) and the wildfire seasons that come with them are why the IPMA’s warnings and the rural-fire rules matter to anyone living outside a city.
• For the island question: Madeira for warm, stable, dry; the Azores for mild, green and wet.