SeasonMapCascais weather in December
Portugal
December in Cascais: cool, a little rain, with clean air — a good time to visit.
#12 of 12 months in Cascais · #866 of 1383 destinations to visit in December · comfort 64/100 (tier C)
Updated September 2026 · climate normals from ERA5 reanalysis
Traveller notes on Cascais in December
Other months in Cascais
Cascais's forum calls July hot and sunny but not especially humid, typically mid-20s to low-30s°C with a regular Atlantic breeze that helps take the edge off. Regulars flag the sea itself as genuinely cold year-round despite the warm air, and note evenings can turn cool enough for a light jacket even after a hot day.
Add your own note from Cascais's card on the map.
Cascais climate normals — December
| Daytime high | 17°C / 62°F | 🙂 cool |
|---|---|---|
| Nighttime low | 12°C / 53°F | |
| Feels like (high) | 15°C / 59°F | |
| Sea temperature | 16°C / 61°F | 🧊 bracing |
| Rainfall | 75 mm / 2.9 in | 🌦 some rain |
| Rainy days | 8 days | |
| Humidity | 81% | 💦 very humid |
| Dew point | 10°C / 51°F | |
| Sunshine | 7.2 h/day | |
| Daylight | 9.5 h | |
| Wind | 22 km/h / 14 mph | |
| Air quality (US AQI) | 38 | 🍃 good |
Monthly averages from ERA5 reanalysis. AQI is the mean US Air Quality Index for the month.
Crowds in Cascais in December
How busy the place itself is — school and mass holidays, the months an editor tagged, and how sought-after the weather makes them. Never part of the comfort score.
Peak crowdsCascais Christmas Village, Christmas holidays in Portugal, school holidays in 7 of the markets that fill it(estimated)
Peak crowdsBusyShoulder seasonQuiet
Best months for Cascais's weather
Ranked by this destination's own climate comfort score across the year — a different thing from how busy it gets (see Crowds above).
Toughest weatherCascais's best weather comes in June, July and September — separate windows, not one continuous season.
Best weatherFair weatherToughest weather
What's on in Cascais in December
Recurring seasonal events, natural spectacles, closures and holidays — curated and sourced.
- Season
Winter swell season
1 Oct – 31 MarSurf seasonThe Atlantic lows that make winter here grey are the same ones that make it the serious surf half of the year, at Guincho and around the point at Carcavelos.
- Festival
Cascais Christmas Village
20 Nov – 5 Jan · usuallyChristmas & New YearCrowdedThe Parque Marechal Carmona is given over to a ticketed Christmas village from late November, which is what fills the town on winter weekends when the beach cannot. Source ↗
Nearby, and something's on
Within 300 km of Cascais — a day trip or a short hop — with something on this month. Never part of the comfort score.
Where is Cascais?
Cascais in December — FAQ
- Is December a good time to visit Cascais?
- December in Cascais: cool, a little rain, with clean air — a good time to visit. It ranks #12 of 12 months for Cascais on SeasonMap's comfort score (64/100).
- What is the weather like in Cascais in December?
- In December, Cascais averages a daily high of 16.6°C and a low of 11.7°C, with about 74.6 mm of rain over roughly 8.2 rainy days.
- What is the air quality in Cascais in December?
- Cascais has a mean US Air Quality Index of about 38 in December.
Other months in Cascais
Compare Cascais in December
Warmer or cooler than Cascais in December
Similar destinations in Southern Europe — December
Within 300 km: Faro's Winter birds on the Ria Formosa around 1 Nov – 31 Mar, and Tavira's Waders on the Ria Formosa around 1 Oct – 31 Mar.