Portugal in September: Warm Seas and the Douro Harvest

September is many locals’ favourite month: still summer weather, the warmest sea of the year, the Douro grape harvest, and the crowds and prices dropping once the school holidays end. Here’s what to expect.

Quick answer: expect highs of 26–28°C in Lisbon and the Algarve, mostly sunny, with the sea at about 21–23°C in the Algarve. Highlights: the Douro harvest (grape picking and treading at the quintas), beach days with fewer people, and perfect weather for everything. Book the Douro early, as harvest weekends are popular.

Why go in September

You get the best of summer without the worst of it. The sea has had all summer to warm up, the days are still long and dry, and from the second week the Portuguese and Spanish families have gone home. It is also harvest time, so the wine regions are at their busiest and most fun. The first rains usually arrive late in the month, mostly in the north.

Weather

• Lisbon: highs around 26–27°C, lows around 18°C. Rain is rare until the last week or so.
• Porto: around 23–24°C, with a higher chance of showers and morning mist by the end of the month.
• The Algarve: around 26–28°C, with the warmest sea of the year (about 21–23°C). The west coast near Lagos and Sagres is a little cooler and windier.
• The Douro: hot days, often over 30°C early in the month, and cooler nights, perfect for the harvest.
• The Alentejo: still hot inland in early September, easing as the month goes on.

Days are still long at the start of the month, with sunset in Lisbon a little after 8pm, but they shorten quickly. By the end of September the sun sets around 7.30pm, so plan beach afternoons and hikes with that in mind.

What’s on

The harvest (vindima)

In the Douro, grape picking usually runs from late August or early September into early October, depending on the year and the altitude of the vineyard. Many quintas offer harvest days where you pick grapes, have lunch with the workers and tread grapes by foot in stone tanks (lagares) in the evening. These sell out, so book weeks ahead. See Douro wine tours and Douro hotels.

Harvests also run in the Alentejo, Bairrada, Dão and the Setúbal Peninsula. Palmela, south of Lisbon, holds its Festa das Vindimas (harvest festival) in early September, with grape treading and the blessing of the first must. See Portugal’s wine regions.

On Madeira, the Madeira Wine Festival runs from late August to mid-September (27 August to 13 September in 2026), with events in Funchal and harvest days in the vineyards of Estreito de Câmara de Lobos. See the Madeira wine guide.

Local festivals

• Nazaré: the festivities for Nossa Senhora da Nazaré take place in early to mid September, with 8 September as the main day at the Sítio above the town. See Nazaré.
• Lamego: the festivities for Nossa Senhora dos Remédios run from late August into early September (27 August to 9 September in 2026). The highlight is the procession on 8 September, when religious images are pulled through the town on ox-drawn floats. See Lamego.
• Ponte de Lima: the Feiras Novas, one of the north’s biggest traditional fairs, with folk groups, concertinas and fireworks, usually in the second week of September (9–14 September in 2026). See Ponte de Lima.
• Viseu: the long-running Feira de São Mateus starts in August and runs into September.
• European Heritage Days: in the second half of the month (18 to 27 September in 2026), museums, palaces and monuments across the country hold special visits and events, many of them free.

The end of the beach season

Official bathing seasons are set by each town, and many end around mid-September, so lifeguards may not be on duty later in the month. At Arrábida, near Setúbal, the 2026 limits on private cars to the beaches ran from 4 June to 15 September, with extra buses and free park-and-ride at the Alegro shopping centre and in Azeitão. In some past years the limits were extended to September weekends, so check before you drive. The coast road between the Figueirinha tunnel and Galapos has been closed since 2023 after rockfalls, so you can’t drive along the shore from Setúbal to Creiro. See the Arrábida beaches.

Where to go

• The Algarve: warm sea, quieter beaches and lower prices after the first week. See the 7-day Algarve itinerary.
• The Douro: the harvest, with the vines turning gold by the end of the month. See the Douro itinerary.
• Lisbon and Porto: great city weather for walking, rooftop bars and day trips.
• The Alentejo coast: places like Vila Nova de Milfontes and Porto Covo are calm again once August ends.
• The Azores and Madeira: warm seas, and whale and dolphin watching runs all year in Madeira.

Crowds and prices

The first week of September still feels like August, with full beaches and high-season prices. Once Portuguese schools go back (usually mid-September), things calm down quickly. Coastal hotel rates often drop noticeably in the second half of the month, while city hotels in Lisbon and Porto stay fairly busy with conferences and short breaks. Douro quintas are the exception: harvest weekends are some of their busiest of the year.

Tips

• Book Douro quintas early for harvest weekends, and ask whether foot-treading is included.
• Best value: after the first week of September, prices drop on the coast.
• Swim at lifeguarded beaches while the season lasts, and respect the flags on the west coast.
• Pack a light jumper for evenings in Porto and the Douro.
• Óbidos and Caldas da Rainha: trains on the Oeste line between Meleças and Caldas have been replaced by buses since storm damage in January 2026, so take an express bus from Lisbon’s Campo Grande instead.

FAQ

Is September a good time to visit Portugal?

Yes. It’s one of the best months: warm and mostly dry, with the warmest sea of the year and fewer crowds after the first week.

Is the sea warm enough to swim in September?

Yes, especially in the Algarve, where it’s usually about 21–23°C. The west coast and the north are cooler, so expect a bracing swim there.

When is the grape harvest in the Douro?

Usually from late August or early September into early October, depending on the year. Book harvest experiences at the quintas weeks ahead.

Is Portugal crowded in September?

The first week is still busy. From mid-September, once schools are back, beaches and coastal towns are much quieter.

More: August, October and Portugal in autumn.

Prices and details change, so please double-check before you travel. Spotted something out of date? Tell us in the groups.