May, June and late September are my pick, for the light and the quieter terraces. The numbers say why: at Cabo da Roca the average August high is 21.9°C against 28.8°C in Lisbon, rain falls on fewer than one day a month in July and August, and the busiest slots at Pena are the summer mornings. Winter is wetter than people expect, eight or nine rain days a month from October to January, and the castle closes in strong wind.
Whatever the month, the day is made or lost in the morning: the hill sits in cloud while Lisbon is sunny, and it lifts by early afternoon. The tours we compared run in any weather and hold or reserve the ticket; the three below say what they do when a palace closes.
Tours that run in any weather
Two of the three name the monuments that replace a closed palace; the third runs in any weather. The half-day and full-day comparisons are in the chips above.
Stas Tours · 4.9/5 · 325 reviews
Pena terraces and Regaleira, tickets bought for you
Tickets bought for you in advance, paid back in cash on the day. Guided at Pena’s terraces and inside Regaleira. Lunch extra.
From €79 per adult · “Sintra Half Day with Pena Palace and Regaleira”
EasyEscape Tours · 5.0/5 · 72 reviews
From Sintra station: Pena’s grounds and Regaleira
Tickets reserved for you, paid in cash on the day. Guided at Pena’s grounds and inside Regaleira. Meals extra.
From €65 per adult · “Half-Day Sintra: Pena Palace, Quinta Regaleira & Town Center”
I Go Portugal · 5.0/5 · 381 reviews
Pena and Regaleira with a private guide
No tickets in the price. Private guide, hotel or port pickup, light refreshments. Lunch extra.
From €100 per adult · “SINTRA PRIVATE TOUR ”
All 8 compared: Half-day Sintra tours →Bookings go through Viator at the same price; we earn a commission.
Why we would book one
- The tickets are bought or reserved for the group whatever the forecast.
- Stas Tours and EasyEscape name the substitutes when a palace closes: the National Palace, Queluz, other monuments. On your own a closure is a refund and a lost morning.
- A guide reorders the day around the cloud; the bus timetable does not.
The year, two months at a time
IPMA climate normals for 1991 to 2020 at Cabo da Roca, the station nearest the serra and the coast, with Lisbon for contrast. The crowds and the fog are our own observations.
| Months | The weather, by the normals | What it means for the day |
|---|---|---|
| Average highs 14°C on the coast, 15 to 16°C in Lisbon; 7 to 9 rain days a month | The camellias in Pena’s park flower from January to March. The castle closed for wind on Dec 16, 2025 and Jan 23 and 24, 2026: check the official notices before going up. Pena at the gate usually works. | |
| 16 to 17°C highs, six rain days a month | The hill greens and the broom flowers on the castle walls. Book Pena a week ahead for Easter and the April holidays. | |
| 19 to 20°C on the coast, 23 to 26°C in Lisbon; rain days fall from five to two | Our pick. Long light, the terraces still empty at 09:30, and the sea fog on the coast most mornings clears by lunch. Book Pena a few days ahead. | |
| 21 to 22°C highs on the coast against 28 to 29°C in Lisbon; under one rain day a month | The coast is the escape from Lisbon’s heat, which is why the hill is full: the morning slots are the most booked, and the cape’s car park is full by 11:00. Come at 09:30 or after 16:00. | |
| 21.5°C in September, 20°C in October; rain returns in October, eight days | Second half of September is the other pick: summer sea, thinner crowds, the light lower on Pena’s terraces at five. October is the last month the coast is warm. | |
| 15 to 17°C highs, nine rain days a month, the wettest of the year | Grey and quiet. Pena’s rooms, Regaleira’s tunnels and the Capuchos are the wet-day sites; the cape and the castle are for the day the wind drops. |
- August average high, Cabo da Roca
- 21.9°C
- August average high, Lisbon
- 28.8°C
- Rain days in July, coast
- 0.5
- Rain days in November, coast
- 9.0
- Coast against Lisbon in August
- 7°C cooler
Normals 1991 to 2020, IPMA station 750 Cabo da Roca (141 m) and station 535 Lisboa Geofísico. The serra itself has no published normal; on Sep 18, 2026 at 14:00 the IPMA station on the hill read 18°C against 28°C in Lisbon. These are long-term averages at two stations, not a forecast for your visit or a reading at Pena.
If your dates are fixed and the forecast is not, the tours above hold the ticket and reroute around a closure; on your own, Regaleira is the fallback when the hill is in cloud.
IPMA, Normais Climatológicas 1991 to 2020, Cabo da Roca (750) and Lisboa Geofísico (535), version 1.0 of 2024, read Sep 18, 2026; a rain day is a day with 1 mm or more. Closures from the Parques de Sintra notices page, checked Aug 29, 2026. Fog, crowds and the car park are the editor’s own observations.
What to change if
- The hill is in cloud at 09:00
- If the Pena slot is not booked yet, do Regaleira or the old town first and Pena after lunch, when the cloud usually lifts. With a booked slot, go up: the rooms are the same in cloud. On a tour, tell the guide.
- A gale is forecast
- Drop the castle and the cape: the castle closes, the cape has nothing to do in a gale, and Pena shuts its outer terraces. The rooms, Regaleira and Monserrate usually stay open.
- You are coming in August
- Book Pena for 09:30 a week ahead, or take a tour that holds it. The coast is the afternoon: 22°C at the cape when Lisbon is at 29.
- You have one grey winter day
- Pena’s rooms and Regaleira’s tunnels: under cover for most of the visit, and bookable the day before in winter. Bring a layer; the hill is several degrees below the town.
Questions
Is Sintra colder than Lisbon?
Yes, and by more than the forecast suggests: the coast normal for August is 21.9°C against Lisbon’s 28.8°C, and the hill is cooler still and often in cloud. Bring a layer even in July.
Does it rain a lot in Sintra?
From October to January, yes: eight or nine rain days a month at the coast station, more in Lisbon. June to September it barely rains: half a day to two days a month. The wet months are the quiet ones.
What time of day is best for Pena and Regaleira?
Opening at 09:30, or after 16:00 when the day-trip groups have gone. Midday in July and August is the slowest way to see it. The morning slots are the most booked, so book them ahead or take a tour that holds one. Regaleira: the first slots at 09:00 or the last after 16:00, and the tunnels are the wet-day plan.
Do the tours run in the rain?
Yes. The tours we compared run in all weather, and several name the monuments that replace a closed palace. If Pena itself closes, Parques de Sintra refunds the ticket and the tour reroutes.
Can I trust the weather forecast for Sintra?
Check the forecast for the place, not the town: the hill and the coast run cooler than Lisbon, and IPMA is the official service for both. This page’s figures are monthly averages at Cabo da Roca and Lisbon, not a forecast for your dates. The hill often sits in cloud in the morning when Lisbon’s forecast says sun, and it usually lifts by early afternoon.