Weather in Sintra - 14-day forecast

Detailed weather forecast for Sintra, Portugal: daytime and night temperature, rain, sunrise and sunset - today and for the next two weeks.

Forecast for the next days in Sintra

today☀️ 29°💧 0.1 mm

Sun☀️ 27°💧 0.9 mm

Mon☀️ 25°💧 0.2 mm

Tue☀️ 23°💧 0.9 mm

Wed☁️ 23°💧 0.1 mm

Thu☁️ 27°💧 1.6 mm

Fri☀️ 30°💧 0.1 mm

Sat☀️ 29°💧 0.6 mm

Forecast vs 1991-2020 climate normal

How does the current forecast compare with normal?

We compare the coming days with weather usually observed at this time of year.

NASA POWER

Friday 11 Sept in Sintra, the forecast high is 30°C. Typical daytime temperatures at this time of year range from 22°C to 26°C, so it will be exceptionally warm. It is warmer than 97% of similar days.

Saturday 5 Sept

29°Cexceptionally warm

usually 23°C–27°C

warmer than 94% of similar days

night: exceptionally warm rain: more rain than usual wind: lighter than usual

Sunday 6 Sept

27°Cwarmer than usual

usually 23°C–27°C

warmer than 85% of similar days

night: exceptionally warm rain: exceptionally wet wind: typical

Monday 7 Sept

25°Cnear normal

usually 23°C–27°C

night: exceptionally warm rain: more rain than usual wind: exceptionally strong

Tuesday 8 Sept

23°Ccooler than usual

usually 22°C–27°C

cooler than 74% of similar days

night: exceptionally warm rain: more rain than usual wind: exceptionally strong

Wednesday 9 Sept

23°Cnear normal

usually 22°C–27°C

night: exceptionally warm rain: more rain than usual wind: typical

Thursday 10 Sept

27°Cwarmer than usual

usually 22°C–27°C

warmer than 82% of similar days

night: exceptionally warm rain: exceptionally wet wind: typical

Friday 11 Sept

30°Cexceptionally warm

usually 22°C–26°C

warmer than 97% of similar days

night: exceptionally warm rain: more rain than usual wind: lighter than usual

How warm was this week in previous years?

Each bar shows the average daily high during the same 7-day period in each year.

swipe to see more years →

cooler yearstypical rangewarmer years2026 forecastcurrent forecast

From 1981 to 2025, the 5-11 Sept period averaged 25°C by day. The coolest year was 2024 (21°C) and the warmest was 1988 (29°C). The current forecast averages 26°C - higher than in 84% of historical years.

Historical reference: NASA POWER daily gridded data (MERRA-2), the 1991-2020 normal and a +/- 7-day calendar window. The typical range is the 20th-80th percentile. This is not a city weather-station reading and does not change the current forecast. NASA POWER Daily API.

Weather warnings - Sintra

Heatyellow level

from 3 Sept, 11:00 to 6 Sept, 20:00

Areas: Portugal

High temperatures and risk of overheating. Drink plenty of water, avoid the midday sun and look after the elderly.

Source: national weather service via Meteoalarm (EUMETNET). Yellow - be aware, orange - be prepared, red - take action.

14-day forecast - Sintra

Sintra - 14-day weather forecast infographic

Sintra 30 & 45-day weather - long-range outlook

Next 16 days · forecast

26°

around 21° at night · days with rain: 1

Weeks 3-4 · avg for September

28°

around 16° at night · rain chance 12%

Weeks 5-7 · avg for October

24°

around 14° at night · rain chance 30%

The 30 & 45-day outlook for Sintra: the next 16 days are a numerical forecast updated daily - on average 26° by day and 21° at night. Further out we rely on multi-year climate averages: around 28° in September, and about 24° in October. Forecasts beyond two weeks are indicative only.

Day-by-day forecast for Sintra

Saturday5 September 2026

☀️29°clear sky

sunrise 07:10 · sunset 20:02 · night 25° · evening 32° · rain 0.1 mm · humidity 48% · wind 5 m/s · clouds 1%

Sunday6 September 2026

☀️27°clear sky

sunrise 07:11 · sunset 20:01 · night 20° · evening 30° · rain 0.9 mm · humidity 57% · wind 7 m/s · clouds 1%

Monday7 September 2026

☀️25°clear sky

sunrise 07:11 · sunset 19:59 · night 19° · evening 22° · rain 0.21 mm · humidity 58% · wind 9 m/s · clouds 79%

Tuesday8 September 2026

☀️23°clear sky

sunrise 07:12 · sunset 19:58 · night 19° · evening 20° · rain 0.93 mm · humidity 58% · wind 9 m/s · clouds 3%

Wednesday9 September 2026

☁️23°broken clouds

sunrise 07:13 · sunset 19:56 · night 19° · evening 21° · rain 0.12 mm · humidity 72% · wind 7 m/s · clouds 78%

Thursday10 September 2026

☁️27°broken clouds

sunrise 07:14 · sunset 19:54 · night 21° · evening 23° · rain 1.56 mm · humidity 51% · wind 6 m/s · clouds 59%

Friday11 September 2026

☀️30°clear sky

sunrise 07:15 · sunset 19:53 · night 25° · evening 26° · rain 0.12 mm · humidity 37% · wind 5 m/s · clouds 4%

Saturday12 September 2026

☀️29°clear sky

sunrise 07:16 · sunset 19:51 · night 24° · evening 25° · rain 0.6 mm · humidity 45% · wind 6 m/s · clouds 1%

Sunday13 September 2026

☀️29°clear sky

sunrise 07:17 · sunset 19:50 · night 21° · evening 23° · rain 0.51 mm · humidity 51% · wind 9 m/s · clouds 10%

Monday14 September 2026

🌤️24°a few clouds

sunrise 07:18 · sunset 19:48 · night 20° · evening 22° · rain 0.84 mm · humidity 58% · wind 12 m/s · clouds 16%

Tuesday15 September 2026

☀️24°clear sky

sunrise 07:19 · sunset 19:46 · night 19° · evening 20° · rain 0.81 mm · humidity 61% · wind 10 m/s · clouds 2%

Wednesday16 September 2026

☀️27°clear sky

sunrise 07:19 · sunset 19:45 · night 20° · evening 22° · humidity 41% · wind 8 m/s · clouds 14%

Thursday17 September 2026

☀️27°clear sky

sunrise 07:20 · sunset 19:43 · night 23° · evening 25° · humidity 38% · wind 7 m/s · clouds 6%

Friday18 September 2026

🌤️28°scattered clouds

sunrise 07:21 · sunset 19:42 · night 22° · evening 23° · humidity 28% · wind 5 m/s · clouds 44%

Saturday19 September 2026

🌤️26°scattered clouds

sunrise 07:22 · sunset 19:40 · night 20° · evening 22° · humidity 48% · wind 4 m/s · clouds 27%

Sunday20 September 2026

☁️24°overcast clouds

sunrise 07:23 · sunset 19:38 · night 24° · evening 24° · humidity 56% · wind 3 m/s · clouds 97%

UV index in Sintra - is it safe to sunbathe?

Today the UV index in Sintra is 7 (high) - unprotected fair skin can burn in about 30 minutes. SPF 30-50, a hat and sunglasses are a must. Better stay in shade between 11:00 and 15:00.

Pollen in Sintra - info for allergy sufferers

Today grasses pollen is highest in Sintra - about 2 grains/m³, low level. Most allergy sufferers should not feel strong symptoms. Pollen levels are a CAMS model forecast and are indicative.

Sea temperature - Sintra

Water today

19°C

Week avg

18°C

Waves today

0.8 m

How's the water?

brisk

16-day sea temperature forecast:

5.09 19°C6.09 19°C7.09 18°C8.09 18°C9.09 18°C10.09 18°C11.09 17°C12.09 17°C13.09 18°C

Average sea temperature through the year:

Jan 16°CFeb 15°CMar 15°CApr 16°CMay 16°CJun 18°CJul 18°CAug 17°CSep 17°COct 19°CNov 18°CDec 16°C

Sea-surface temperature from marine models, updated daily. See also: where the sea is warmest right now.

Sintra weather through the year

Upcoming public holidays in Portugal: Republic Day — 5 October · All Saints Day — 1 November · Restoration of Independence — 1 December.

Nearby and related places

LisbonAlgarvePortoCoimbraPonte de LimaÉvoraMadeira

FAQ - Sintra weather

What is the weather like in Sintra today?

Today it is about 29° during the day and 25° at night, clear sky.

How far ahead can I check the forecast for Sintra?

This page shows a detailed 14-day forecast plus the long-term monthly climate, so you can plan both a short trip and a holiday months ahead.