Things to Do in Cascais in September
September weather, activities, events & insider tips
September Weather in Cascais
Is September Right for You?
Advantages
- Post-summer tourist exodus means 40% fewer crowds at Boca do Inferno and Quinta da Regaleira while maintaining 24°C (76°F) daily highs
- Atlantic Ocean temperature peaks at 19°C (66°F) - warmest swimming conditions of the year with calmer seas after August winds
- Perfect hiking weather with cool 17°C (62°F) mornings for Sintra trails before afternoon heat, plus clear visibility for coastal walks
- September harvest season brings fresh seafood festivals and wine tastings at local quintas with 30% lower accommodation rates than July-August
Considerations
- Morning coastal fog until 10am can obscure sunrise views and delay boat departures - plan outdoor activities after 11am
- Variable weather patterns mean packing for both 17°C (62°F) evenings and 24°C (76°F) afternoons in the same day
- Some beach clubs and seasonal restaurants begin closing mid-September, limiting late-night dining options compared to summer months
Best Activities in September
Sintra Palace and Gardens Tours
September's mild 17°C (62°F) mornings make the uphill walks to Pena Palace and Quinta da Regaleira comfortable before crowds arrive. Clear autumn air provides spectacular Atlantic views from palace terraces that are often hazy in summer heat. Gardens are at their most photogenic with post-summer blooms.
Coastal Hiking and Cliff Walking
September offers ideal hiking conditions with comfortable temperatures and minimal rainfall. The Cabo da Roca to Praia da Ursa trail (6 km/3.7 miles) is perfect in 20°C (68°F) afternoon temperatures. Atlantic winds are gentler than summer, making cliff-edge paths safer and more enjoyable.
Atlantic Ocean Surfing and Water Sports
September brings the year's warmest ocean temperatures at 19°C (66°F) with consistent 1-2 meter swells. Post-summer winds create better surfing conditions than the choppy August seas. Water visibility is excellent for stand-up paddleboarding around Cascais Bay.
Lisbon Day Trip Experiences
September's comfortable temperatures make walking Lisbon's hills enjoyable, and tourist crowds thin after summer holidays. Tram 28 rides are less crowded, and outdoor dining in Alfama is pleasant in evening temperatures around 18°C (64°F). Cultural sites have shorter queues.
Wine Estate and Quinta Visits
September is harvest season at Colares vineyards, offering unique sand-grown wine tastings unavailable other months. Cooler morning temperatures make cycling between quintas comfortable. Local wine festivals occur throughout September with harvest celebrations.
Seafood and Market Food Tours
September brings peak seafood season with fresh sardines, sea bass, and local specialties. Morning markets are comfortable to explore in 18°C (64°F) temperatures. Outdoor dining extends later into evening with pleasant 17°C (62°F) temperatures after 9pm.
September Events & Festivals
Festival do Marisco de Cascais
Annual seafood festival featuring local fishermen's catches, traditional preparation methods, and outdoor dining along Cascais Bay. Live fado music and cooking demonstrations showcase Portuguese coastal culture.
Colares Wine Harvest Festival
Traditional grape harvest celebration at historic sand-grown vineyards. Visitors can participate in grape picking, learn about unique terroir, and taste exclusive harvest wines available only during September.