August · Portugal
Best time to visit Cascais in August Weather, crowds & prices
Weather in Cascais in August
Average temperature 20°C, 2 mm of rain, about 31 days with 6+ hours of sunshine and 82% humidity — based on the five most recent complete years of ERA5 data (2021–2025).
August score
8.5/10
Ranked #1 of 12 months
- Avg temp
- 20°C
- Rainfall
- 2 mm
- Humidity
- 82%
- Days with 6h+ sun
- 31
- Crowd Density
- Peak Tourist Rush
- Average Expenses
- $$$ · Peak Season Rates ($$$)
August in Cascais scores 8.5/10 for beach and coastal travel - the single best month of the year. Expect around 20°C, 2 mm of rain, and roughly 31 days with 6+ hours of sunshine this month.
Cascais pairs a walkable former fishing town with sheltered beaches, an Atlantic promenade, and the wilder coast toward Guincho.
August in Cascais tops the year's climate scores
With 20°C (69°F) on average, August delivers classic beach weather: plenty of time in the water, with beach and boat plans rarely disrupted by cold.
At just 2 mm for the month, rain will not shape your plans; you get about 31 days with 6+ hours of sunshine and 13.5 hours of daylight.
On our climate-comfort scale this is the top-ranked month of the year for Cascais at 8.5/10 — the reference point every other month on this page is measured against.
Pack light clothing, swimwear and real sun protection.
Budget for peak pricing, and this is one of the busiest months here. You are paying the year's highest rates for the year's best conditions — book early or shift a few weeks either side.
Frequently asked
- What is the weather like in Cascais in August?
- In August, Cascais averages 20°C, 2 mm of rain, and about 31 days with 6+ hours of sunshine. Its climate-comfort score is 8.5/10.
- Is August a good time to visit Cascais?
- August earns a 8.5/10 climate-comfort score. Use the year-round chart to weigh the weather against your budget and crowd preferences.
- How much does it rain in Cascais in August?
- Expect about 2 mm of rain in August. Average humidity is 82% and there are about 31 days with 6+ hours of sunshine.
Curated in Cascais
Tickets & experiences
Things to do in Cascais
Cascais, Portugal. Live activities and tours from GetYourGuide, matched to this destination.