September in Portugal lands squarely in autumn. Expect average daytime highs of 27°C (81°F) and overnight lows around 17°C (63°F) in Lisbon, with the Algarve typically two to three degrees warmer at 28°C (82°F). The Atlantic sits at roughly 21°C (70°F), and you can plan for about 9 hours of sunshine on a normal day. Golden, slightly softer than August. The Atlantic stays warm well into October.
FAQ
Is September a good time to visit Portugal?
Yes. Many seasoned travellers' favourite month. Warm sea, lighter crowds, harvest in full swing. The country is at its most alive, with festivals, long evenings and a warm Atlantic.
What should I pack for Portugal in September?
Layers you can shed during the day, a light jacket for cooler evenings, sunglasses and comfortable shoes. The light is strong even when temperatures are mild.
Will it rain a lot in Portugal in September?
On average, September sees around 3 days with some rain in Lisbon, often short showers between long sunny spells. The south is consistently drier than the north, and the Algarve in particular stays sunny on most days even in winter.