SINTRA · AUGUST · 38.8° N
Sintra in August runs on two thermometers. One sits at Lisbon’s airport, where the 1991-2020 August normal is a high of 84.2°F and a low of 65.3°F. The other is the hill itself, 20 km west, where cloud forms on the Serra and the mornings run colder and mistier than any airport reading suggests. Both are true, and knowing which one you packed for decides the day. The gates, meanwhile, run on published hours: Pena’s park opens at 09:00, its palace at 09:30.
What the month takes is elbow room. August falls in the heart of the European holiday season, and the eleven parks and monuments run by Parques de Sintra, from Pena down to the Cabo da Roca lighthouse, work their long summer hours through it. What it hands back is weather that rarely interrupts a plan: 0.20 inches of rain across the whole month, and one day, on average, that records as much as 1 mm (0.04 inch).
SINTRA IN AUGUST · 1991-2020 NORMALS
August is Sintra’s dry, late-opening month: 84.2°F by day, measurable rain on a single day in an average month, park gates at Pena and Monserrate open to 19:00 and the sun up until 20:32.
AVG HIGH 84.2°F · 0.20 IN OF RAIN · 13H 43M OF DAYLIGHT ON AUG 15
Go for: dry days you can plan three days ahead, park gates open to 19:00 at Pena and Monserrate, and light in the town until 20:32.
Think twice before: booking an unshaded afternoon on Pena’s terraces or the Moorish Castle walls at 84.2°F, or arriving after 17:30, when Pena’s palace has already taken its last admission.
Climate: IPMA 1991-2020, station 579 · Hours and prices: Parques de Sintra, read Sep 22, 2026 · full sources at the end
On this page
- Average highs, lows and rain daysThe August normals, and which thermometer they come from
- How hot the afternoons get84.2°F by day, 65.3°F at night
- Ticket prices and closing timesWhat the gates charge, and what we could not verify
- Things to do in Sintra in AugustPena, Monserrate, Capuchos and Cabo da Roca
- A two-day plan built around the heatTwo days, gate by gate
- August or September?How the three months compare
- Is August a good time to visit?Our verdict, and who should shift
- Sintra in July insteadThe July page
- The whole country, month by monthPortugal’s 12-month verdict
Every figure here comes from one instrument, and it is worth knowing which. IPMA, Portugal’s national weather service, publishes the 1991-2020 normals for station 579, Lisboa Gago Coutinho, altitude 103.9 m: a real thermometer, not a reanalysis grid cell. It stands at the airport, 20 km east of the Serra and far lower. For trains, beds and the full monument list, the Sintra guide covers the ground that has no date on it.
Sintra weather in August: average highs, lows and rain days
| August at station 579 (Lisboa Gago Coutinho) | 1991-2020 normal |
|---|---|
| Average high | 84.2°F (29.0°C) |
| Average low | 65.3°F (18.5°C) |
| Day-night spread | 18.9°F |
| Precipitation | 0.20 in |
| Days with 1 mm (0.04 in) or more | 1.0 |
| Days with 10 mm (0.39 in) or more | 0.1 |
| Daylight on August 15 | 13h 43m |
IPMA’s August normals read 84.2°F for the average high, 65.3°F for the average low and 0.20 inches of precipitation, measured over 1991-2020 at station 579, Lisboa Gago Coutinho, 103.9 m above sea level. That is an actual thermometer rather than a model cell, which matters when a page hands you a decimal. It also sits at the airport, 20 km from the hill. Cloud forms on the Serra itself, and the high ground runs several degrees colder and much mistier, so read the table as the valley’s August, not Pena’s terrace at nine in the morning.
Measurable rain shows up once in an average August: 1.0 day records at least 1 mm (0.04 inch), and 0.1 day records 10 mm (0.39 inch) or more, which works out to one genuine soaking roughly every ten Augusts. Two cautions ride with those counts. They use IPMA’s thresholds, not the 0.10-inch threshold American climate tables use, so the numbers are not interchangeable with a US page. And they describe the airport, while the hill collects a good deal of its moisture as mist that no rain gauge counts.
Pack for close to 19 degrees of swing between the average night and the average afternoon. A light long-sleeve layer at the Pena gate at 09:00, with cloud still in the eucalyptus, is not overcautious, and by two in the afternoon down in the town it is dead weight in a daypack. Shoes matter more than clothes. The Moorish Castle’s wall walk and the paths inside Pena’s 210-hectare park are stone, slope and tree root, in that order.
On August 15 the sun rises at 06:49 and sets at 20:32 local time, giving 13 hours 43 minutes of daylight (sunrise-sunset.org computes it in UTC, 05:49 to 19:32, and Portugal runs an hour ahead in summer). The monuments shut well before the light does. Pena’s park takes its last admission at 18:00 and closes at 19:00, which leaves an hour and a half of daylight afterward for the town, where the gardens of the National Palace are free to walk into.
How warm is Sintra in August?
August is the warmest of the three summer months on this record. Its 84.2°F average high beats July’s 82.9°F and September’s 80.2°F, and its 65.3°F average low is the highest of the three as well. The distance between the two, 18.9°F, is what you actually feel in a day here. Remember that the hill sits under both figures: the station is coastal lowland, and the Serra is the cold, cloudy exception 20 km away.
In practice you dress for two climates before lunch. Mornings at the Pena and Monserrate gates, both open at 09:00, can be gray and damp enough for sleeves. Afternoons in the town, on the Moorish Castle ramparts or on the walk between Pena’s entrance and the palace door are full summer, with no shade on the exposed sections. Water, a hat and a bag you can shed a layer into cover the gap. Nothing heavier is needed in August.
Freezing nights are not part of this month. We have no count of sub-32°F nights for station 579, and with an average low of 65.3°F in August the question does not arise. The water is the real gap in our file: we could not verify a sea-surface temperature for the Sintra coast, so no swimming figure appears here. If you meet one in another table, check the method, because most sea tables average daily maxima and therefore read warmer than a true 24-hour mean.
How busy is Sintra in August? Crowds, ticket prices and booking ahead
August sits at the top of the European holiday calendar, which is a fact of the school year rather than of a price sheet. We found no occupancy series and no room-rate series for Sintra, so we crown no month expensive and none cheap. What we can quote are the gate prices Parques de Sintra published on 22 September 2026: 12 EUR for Pena’s park alone, 20 EUR for the Essential visit to park and palace, 45 EUR for the Full Tour, and free entry for children under 6.
On reservations we can only hand you the clock. We could not verify a timed-entry rule or a booking lead time from an operator page, so no number of weeks appears here. The published closing sequence does the work instead. Pena’s palace takes its last admission at 17:30 and the park at 18:00, the Moorish Castle closes at 18:00 with last entry at 17:30, and the Convent of the Capuchos shuts at 17:30 after opening at 09:00. Arrive at four in the afternoon and only the town’s National Palace, open to 18:30, is still takeable.
We could not verify a lodging-tax rate for Sintra, or whether one applies, so we quote no percentage. Budget the part we can document. Two adults doing Pena’s Essential visit at 20 EUR each, the Moorish Castle at 12 EUR and the National Palace at 13 EUR spend 90 EUR on gates in one day, before anything they eat.
One upgrade genuinely changes an August day, and it costs 4.50 EUR: the round-trip transfer between Pena’s park entrance and the palace door. In February it is a convenience. At 84.2°F with the uphill stretch in full sun, it is the line on the bill that decides how the afternoon goes. Pena’s 45 EUR Full Tour against the 20 EUR Essential is a different question altogether, since it buys more rooms rather than less climbing.
Things to do in Sintra in August: Pena, Monserrate, Capuchos and Cabo da Roca
The long evening is what August offers that the winter months cannot. Park gates at Pena and Monserrate stay open until 19:00, the sun holds until 20:32 on the 15th, and with 0.20 inches of rain in the entire month an outdoor plan made three days ahead usually survives contact with the sky. Four weeks later, September brings 1.41 inches across 3.7 days with measurable rain, and the same plan needs an indoor version.
The hill is documented to the hectare. Pena’s park covers 210 hectares behind a stone wall, taking in the Tapada do Mocho and the Moorish Castle, planted from about 1840 by Ferdinand II with species brought from North America, Asia and New Zealand. Monserrate holds 50 hectares on the northern slopes and more than 3,000 exotic species, sited after an analysis of the land’s microclimatic zones. Entry runs 12 EUR at Monserrate, 12 EUR at the Moorish Castle (10 EUR at 6 to 17 and over 65), 11 EUR at Capuchos and 13 EUR at the National Palace.
None of that planting changes with the month. The air around it does, and that is the argument for order of visits: Monserrate’s 50 hectares face north, so its lower gardens hold the morning coolness that Pena’s exposed terraces lose by eleven. Cabo da Roca is the opposite trade. The lighthouse courtyard and interpretation center at the westernmost point of mainland Europe open 09:30 to 17:30, at 5 EUR for the Essential visit and 10 EUR to go up the tower, and the Atlantic wind comes with the ticket.
Two doors on the hill cost nothing. Villa Sassetti, one of the eleven properties Parques de Sintra runs, is free from 10:00 to 18:00. So are the gardens of the National Palace in the town center, which is useful at 18:30 in August, when the paid gates have closed and there are still two hours of daylight to spend.
Sintra in August: a two-day itinerary
Day one starts at Pena’s park gate at 09:00, while the hill still holds its morning cloud, with the palace opening half an hour later. Take the 4.50 EUR round-trip transfer up if the sun is already out, walk it if it is not. Out by 11:30, the Moorish Castle next door (12 EUR, 09:30 to 18:00) is still bearable on the walls. Lunch in the town below, then the National Palace at 13 EUR until 18:30.
Day two goes west and downhill. Monserrate’s park opens at 09:00 and its palace at 09:30, 12 EUR for 50 hectares on the cool side of the Serra. The Convent of the Capuchos, 11 EUR, closes at 17:30, so it goes before the coast rather than after. Finish at Cabo da Roca, which also shuts at 17:30. If the month’s one wet day lands on you, flip the order and spend the morning in the palace interiors at Monserrate and in the town, remembering that only 0.1 day in an average August reaches 10 mm.
Sintra in August vs July and September
| 1991-2020 normal | July | August | September |
|---|---|---|---|
| Average high | 82.9°F (28.3°C) | 84.2°F (29.0°C) | 80.2°F (26.8°C) |
| Average low | 64.4°F (18.0°C) | 65.3°F (18.5°C) | 63.3°F (17.4°C) |
| Precipitation | 0.11 in | 0.20 in | 1.41 in |
| Days with 1 mm (0.04 in) or more | 0.4 | 1.0 | 3.7 |
August tops the three months at both ends of the day: 84.2°F against July’s 82.9°F and September’s 80.2°F, and 65.3°F at night against 64.4°F and 63.3°F. Rain sorts them differently. July is the driest at 0.11 inches over 0.4 days, August sits close behind at 0.20 inches over 1.0 day, and September changes the season entirely with 1.41 inches, seven times August’s total, spread across 3.7 days. The water is the column we cannot fill, since we found no verified sea-surface reading for this coast in any of the three.
Moving four weeks either way is a small trade made of known numbers. Going back to July takes 1.3°F off the afternoon and buys the driest of the three months, inside the same holiday block. Going forward to September takes 4.0°F off the high and costs nearly four times the wet days, in return for cooler walking on the same slopes. The July page runs these figures for that month, and our 12-month verdict for Portugal sets them against the rest of the country.
Is August a good time to visit Sintra?
For a traveler who wants gates open late and a plan that rain will not cancel, August is a straight yes: 0.20 inches for the month, 13 hours 43 minutes of daylight on the 15th, park gates at 19:00. For anyone who fades above 80°F, the answer is no, and the 84.2°F normal is the polite version of an unshaded terrace at Pena at three in the afternoon. Families with young children get one small break, since children under 6 enter free.
If the answer is no, September is the month to move to rather than July. You give up 4.0°F of afternoon heat and take on 1.41 inches of rain across 3.7 days, which is a real change in how a hill day is planned. July is the drier alternative at 0.11 inches, but it runs only 1.3°F cooler and sits in the same holiday weeks, so it solves less than people expect.
What neither neighbor matches on this record is the pairing: August holds the warmest normals of the three, 84.2°F by day and 65.3°F at night, while recording measurable rain on a single day.
The last word
Settle one thing before you book anything else: whether your August day begins at Pena’s 09:00 gate, because the rest of the hill arranges itself around that decision and the 17:30 last admission closes the argument. A fact we have not served yet, and one that explains why eleven separate doors charge separate prices here. The Cultural Landscape of Sintra was inscribed by UNESCO in 1995 under criteria (ii), (iv) and (v), covering 946 hectares inside a 3,641-hectare buffer zone, sitting within the Sintra-Cascais Natural Park and classified a National Monument under Portuguese law since 1994. Carry the morning layer, and pay the 4.50 EUR at three in the afternoon.
Sources & data for this guide
- August normals (84.2°F high, 65.3°F low, 0.20 in) and rain-day counts at 1 mm and 10 mm · IPMA, climatological normals 1991-2020, station 579 Lisboa Gago Coutinho, altitude 103.9 m · checked Sep 22, 2026
- July and September normals used in the comparison table · same IPMA station and same 1991-2020 period · checked Sep 22, 2026
- Daylight, sunrise and sunset for August 15 (05:49 to 19:32 UTC, converted to local) · sunrise-sunset.org · checked Sep 22, 2026
- Opening times and adult prices at Pena, the Moorish Castle, Monserrate, the Convent of the Capuchos, the National Palace of Sintra, Villa Sassetti and the Cabo da Roca lighthouse · Parques de Sintra – Monte da Lua · checked Sep 22, 2026
- Inscription year and criteria, 946-hectare property and 3,641-hectare buffer zone, Pena’s 210 hectares, Monserrate’s 50 hectares and 3,000 species, Natural Park status · UNESCO World Heritage Centre, file 723 · checked Sep 22, 2026
- Editorial admission: the thermometer we quote stands at Lisbon’s airport, 20 km from the Serra and much lower, and the hill runs colder and mistier. We could not verify a hill-top station, a sea-surface temperature for this coast, a lodging-tax rate, an occupancy or room-rate series, or the train fare and journey time from Lisbon. Hours and prices change · confirm with the operator when you book.