SINTRA · DECEMBER · THE MONTH GUIDE
December gives Sintra nine hours and thirty-one minutes of daylight on the 15th, an average high of 58.8°F and an average low of 47.7°F. Rain falls on 9.7 days of the month and totals 3.94 inches. None of that closes a gate: Pena’s park still runs 09:00 to 19:00 and its palace 09:30 to 18:30 on the hours Parques de Sintra published in September 2026. The sun sets at 5:17 pm, so two of the park’s opening hours fall after dark.
The hill itself is the complication. The Cultural Landscape of Sintra, 946 hectares inscribed by UNESCO in 1995 and sitting inside the Sintra-Cascais Natural Park, climbs well above the station that supplies the figures below, and it makes its own cloud. Expect the Serra to run colder and mistier than any number here. For the town in any month, the Sintra guide covers the ground, and our best-time page ranks the twelve.
THE MONTH AT A GLANCE · SINTRA IN DECEMBER
December is Sintra’s short-daylight month: 58.8°F by day, measurable rain on roughly one day in three, and every published palace hour intact, so the plan bends around a 5:17 pm sunset rather than around the weather.
AVG HIGH 58.8°F · 9.7 RAIN DAYS · 9H31M OF DAYLIGHT · SUNSET 5:17 PM
Go for: the 210-hectare Park of Pena walked uphill without summer heat, Monserrate’s 3,000-plus species at €12, and Cabo da Roca’s lighthouse courtyard at €5.
Think twice before: planning anything outdoors after 5:17 pm, and before counting on a sea day: we found no water-temperature series for this coast and quote no figure.
Climate: IPMA station 579, 1991-2020 · Hours and prices: Parques de Sintra, 22 Sep 2026 · full sources at the end
On this page
- Sintra weather in December58.8°F days, 3.94 inches, 9.7 wet days
- How cold the nights get, and the water questionA 47.7°F average low, and no sea figure we can stand behind
- Crowds, ticket prices and the tourist taxWhat Parques de Sintra charges, and what we could not verify
- Things to do in Sintra in DecemberPena, Monserrate, the Moorish Castle, Cabo da Roca
- A two-day plan around 9h31m of daylightHour by hour, both days
- December vs November and JanuaryHow the three months compare on heat and rain
- Is December a good time to visit Sintra?Who it suits, and who should shift four weeks
Two gaps worth stating up front. Where to sleep and how to reach the hill belong to the Sintra guide and to our transport page, and we could not read a Lisbon-to-Sintra train fare or journey time from an operator page, so we quote neither. Every ticket price given below is the one Parques de Sintra published on 22 September 2026.
Sintra weather in December: average highs, lows and rain days
| Measure | December, 1991-2020 normals |
|---|---|
| Average high | 58.8°F (14.9°C) |
| Average low | 47.7°F (8.7°C) |
| Precipitation | 3.94 in |
| Days with 0.04 in (1 mm) or more | 9.7 |
| Days with 0.39 in (10 mm) or more | 3.5 |
| Daylight on December 15 | 9h 31m |
| Sunrise and sunset, December 15 | 7:46 am · 5:17 pm |
The figures come from IPMA, Portugal’s national weather service, and from a real thermometer rather than a model grid cell: station 579, Lisboa Gago Coutinho, at 103.9 m, on the 1991-2020 normals. December there averages a high of 58.8°F, a low of 47.7°F and 3.94 inches of precipitation. That station stands about 20 km from Sintra, at the airport, and far lower. Every figure here carries the caveat, because the Serra generates its own cloud and runs several degrees colder and mistier than the lowland reading.
Rain reaches IPMA’s 1 mm threshold, 0.04 inch, on 9.7 days in an average December, which works out to wet ground roughly one day in three. The heavier days, 0.39 inch and up, come around 3.5 times in the month. US almanacs usually count from 0.10 inch, so the two sets of wet-day counts are not interchangeable. In practice a December day here is far more often gray with passing showers than washed out from breakfast to dark.
Eleven and a bit degrees separate the average high from the average low, a narrow daily swing by winter standards and a wider one in effect once altitude and an Atlantic wind are added on the Serra. A waterproof shell matters more than a thick coat, and shoes with grip matter more than either, since the climb to the Moorish Castle is worn stone. Our packing page has the full list.
On December 15 the sun rises at 7:46 am and sets at 5:17 pm local time: 9 hours 31 minutes of daylight. Pena’s palace takes its last visitors at 17:30 and the park at 18:00, both at or after sunset. Sightseeing that starts at 10:00 has already given away an hour it would have kept in November. Treat 4:00 pm as the end of the outdoor day and save the indoor rooms for the tail of it.
How warm is Sintra in December, and can you swim off this coast?
58.8°F by day, 47.7°F by night, 11.1 degrees between them: that is December’s range at the reference station. November averages 4.9 degrees warmer by day and January 0.9 degrees cooler, so the month occupies the flat floor of the year’s curve rather than a spike of its own. Nothing in the normals suggests a month that swings hard from one week to the next.
Mornings at 47.7°F want a fleece under a shell. An afternoon at 58.8°F in sun wants the fleece off and in the bag. The practical problem is the hill: cloud, an ocean wind, and a walk from Pena’s park entrance to the palace door that goes up the whole way. Layers you can shed between the two, plus the €4.50 round-trip transfer on a day when it is pouring, beat one heavy coat.
We found no count of frost nights for the Serra, so we give none. The airport station’s average December low of 47.7°F sits nearly sixteen degrees above freezing, but it measures the lowland, not the ridge. The water gets the same treatment: we could not verify a sea-surface temperature series for this stretch of coast, and where such series exist they usually average daily maxima, which reads warmer than a 24-hour mean. So we quote no swimming number at all.
How busy is Sintra in December? Crowds, prices and the tourist tax
December falls outside the summer season on the calendar, and that is as far as our data takes us. We found no occupancy series and no monthly room-rate series for Sintra, so we crown no month cheapest and none dearest. What is fixed is the published price list: Pena’s park alone at €12, the Essential park-and-palace visit at €20, the Full Tour at €45, children under 6 free.
How far ahead December entry slots fill is something we could not verify, so no lead time appears in our advice. The constraint we can date is the clock. With last admission to the palace at 17:30 and only 9 hours 31 minutes of daylight, arrivals compress into a single mid-morning to mid-afternoon block, and a 09:30 entry uses the first of those hours instead of competing for the middle ones.
On the tourist tax, we have nothing verified. We could not read a per-night municipal rate from an official page, so we give no amount and no exemption. Budget instead against the ticket prices, which are published and stable: €13 for the National Palace of Sintra in town, €12 for the Moorish Castle, €12 for Monserrate, €11 for the Convent of the Capuchos.
One upgrade changes December specifically. The €4.50 round-trip transfer between Pena’s park entrance and the palace door removes a steep climb that turns miserable on the 3.5 days a month when 0.39 inch or more falls. The €45 Full Tour against the €20 Essential buys rooms, not shelter, so it answers a different question. At Cabo da Roca, €10 instead of €5 puts you up the lighthouse tower while the sun is already low.
Things to do in Sintra in December: Pena, Monserrate and Cabo da Roca
Uphill walking is what this month hands you. The Park of Pena covers 210 hectares behind a stone wall, takes in the Tapada do Mocho and the Moorish Castle, and climbs almost continuously. At a 58.8°F average high that is a walk rather than an ordeal. Ferdinand II laid the park out from about 1840 and planted it with species brought from North America, Asia and New Zealand, which is why the December version still reads green rather than bare.
Parques de Sintra runs eleven parks and monuments in and around the town, and four of them carry a roof for part of the visit. The National Palace of Sintra, in the town center, opens 09:30 to 18:30 and costs €13 for the Essential visit. Pena’s palace runs 09:30 to 18:30, last admission 17:30, €20 with the park. Monserrate opens its park 09:00 to 19:00 and its palace 09:30 to 18:00 for €12, holding over 3,000 exotic species across 50 hectares. The Moorish Castle, €12, closes at 18:00 and has no roof at all.
A garden planted for its microclimates barely registers the month. Monserrate’s species were chosen after a careful analysis of the microclimatic zones on the northern slopes, and it is the air around them that moves, down to a 58.8°F December average. The hours move too, and that is the real December edit. The Convent of the Capuchos shuts at 17:30 and Cabo da Roca’s courtyard at 17:30, both within minutes of sunset, so their last slot is the last of the light. In a long-daylight month the same closing time leaves an evening behind it.
Free in December, as in any month: Villa Sassetti, 10:00 to 18:00, and the gardens of the National Palace of Sintra. Children under 6 walk into Pena for nothing. Watch the mismatch the short month creates, though. Villa Sassetti’s gate stays open until 18:00, forty-three minutes after the sun has gone on the 15th, so the free climb needs to happen before 4:00 pm to be worth the legs.
Sintra in December: a two-day itinerary
Day one starts against a 7:46 am sunrise. Be at Pena’s park gate for the 09:00 opening and inside the palace when it opens at 09:30, on the €20 Essential, adding the €4.50 transfer if the sky looks wrong. Out by 11:30, then walk the 210 hectares downhill toward the Moorish Castle, €12, where the walls are exposed and the light is best before 2:00 pm. Into town for a late lunch, and hold the National Palace of Sintra, €13, for 3:30 pm and after, with its 18:30 close as the backstop.
Day two runs west. Monserrate at 09:00 for the park and 09:30 for the palace, €12, gives an hour and a half of the 50-hectare garden plus the rooms. Then Cabo da Roca, the westernmost point of mainland Europe, whose courtyard and interpretation center close at 17:30: €10 climbs the tower, €5 does not. If the rain turns heavy, drop the cliff, take the Convent of the Capuchos at €11 before its 17:30 close, and spend the wet end of the day inside the National Palace rather than on an exposed headland at 47.7°F.
Sintra in December vs November and January
| Measure | November | December | January |
|---|---|---|---|
| Average high | 63.7°F | 58.8°F | 57.9°F |
| Average low | 52.2°F | 47.7°F | 46.0°F |
| Precipitation | 4.51 in | 3.94 in | 3.78 in |
| Days with 0.04 in (1 mm) or more | 9.3 | 9.7 | 9.9 |
| Sea temperature | Not verified | Not verified | Not verified |
November is the warm one: 63.7°F by day against December’s 58.8°F, a 4.9-degree gap you feel standing on an exposed wall. January gives up only another 0.9 degrees, at 57.9°F. Rainfall runs the other way, from 4.51 inches in November to 3.94 in December and 3.78 in January, while the wet-day count creeps up, 9.3 to 9.7 to 9.9. Divide one into the other and November’s rain arrives in fewer, fatter days and January’s in more and smaller ones. No sea-surface series was available to us for any of the three.
Shifting four weeks back buys those 4.9 degrees and a later sunset, and costs 0.57 inch of extra rain. Shifting four weeks forward costs almost nothing in temperature, saves 0.16 inch, and picks up daylight again at the far end of the month. Both neighbors carry the same station’s normals in full, in our November page and our January page.
Is December a good time to visit Sintra?
Yes if your Sintra is palaces and walking. The monuments keep their published hours, 58.8°F is a good temperature for a 210-hectare uphill park, and rain on 9.7 days out of 31 still leaves two days in three without it. No if you need long afternoons or a coast day: 9 hours 31 minutes of daylight is the real constraint, and we have no water temperature to offer you in exchange.
For anyone in that second group, November is the month to shift to rather than January. It pays 63.7°F daytime highs and a later sunset in return for 0.57 inch more rain, which is the better trade when the plan is mostly outdoors. January holds December’s rain profile almost exactly and takes another degree off the top of the day.
What December offers that November does not: 0.57 inch less rain across the month, over the same published opening hours and at ticket prices that do not move with the season.
The last word
Book the 09:30 palace entry, carry a shell rather than a coat, and treat 4:00 pm as the end of the outdoor day. One figure we have kept back: beyond the 946 hectares UNESCO inscribed in 1995 under criteria (ii), (iv) and (v), a buffer zone of 3,641 hectares wraps the property, all of it inside the Sintra-Cascais Natural Park and protected by national legislation since 1994. The whole of it holds National Monument status in December as in July.
Sources & data for this guide
- December normals, rain-day counts and thresholds · IPMA, normais climatológicas 1991-2020, station 579 Lisboa Gago Coutinho, altitude 103.9 m · checked Sep 22, 2026
- November and January normals · same IPMA station, same 1991-2020 period · checked Sep 22, 2026
- Sunrise 7:46 am, sunset 5:17 pm and 9h 31m of daylight on December 15 · sunrise-sunset.org · checked Sep 22, 2026
- Opening times, ticket prices, free sites and the €4.50 transfer · Parques de Sintra – Monte da Lua, Opening Times and Prices · checked Sep 22, 2026
- 946-hectare property and 3,641-hectare buffer zone, 1995 inscription, Pena’s 210 hectares, Monserrate’s 50 hectares and 3,000 species · UNESCO World Heritage Centre, file 723 · checked Sep 22, 2026
- We could not read a Lisbon-Sintra train fare, a journey time or a Serra bus timetable from an operator page, and we found no sea-surface series, no occupancy data and no municipal tourist-tax rate. Those figures are missing because we could not verify them, not because they do not exist.