Last updated: February 24, 2025
Experience the delightful charm of Sintra, Portugal, in September when the weather strikes a perfect balance between warmth and freshness. With maximum temperatures reaching 23°C (74°F) and an average of 18°C (65°F), visitors can enjoy mild, comfortable days. The minimum temperature hovering around 15°C (60°F) ensures pleasant evenings ideal for outdoor exploration. While the month brings an average precipitation amount of 32 mm (1.2 in) over just 2 days, the humidity at 67% adds a touch of richness to the air, enhancing the beauty of Sintra's lush landscapes. September is a perfect time to uncover the magical allure of this historic town, where every stroll is graced with lovely weather.
As summer gently transitions into autumn, September in Sintra, Portugal, offers a delightful climate that remains pleasantly warm. With minimum temperatures around 15°C (60°F) and averages settling at 18°C (65°F), visitors can enjoy the lingering warmth of summer. The maximum temperature reaches a comfortable 23°C (74°F), creating ideal conditions for exploring the lush landscapes and historic architecture that Sintra is famous for. This month marks a subtle shift from the sizzling heat of August, maintaining a balance that allows outdoor adventures while inviting evenings that are conducive to relaxed strolls and delicious meals in the charming streets. Whether you're hiking through the hills or visiting palaces, September provides the perfect backdrop for enjoying the beauty of this iconic Portuguese destination.
In September, Sintra experiences a transition as summer gives way to autumn, marked by a modest precipitation amount of 32 mm (1.2 in) over just two days of rain. This is a notable increase from the nearly rainless months of July and August, which only saw 3 mm and 4 mm respectively. Compared to the peak rainfall of November at 89 mm, September’s showers play a subtle role in hinting at the approaching wetter months. With its lush landscapes and historic charm, the scattered rain can enhance Sintra's beauty, making the rich greenery even more vibrant for those exploring the region. As the rains return, the weather remains pleasantly mild, striking a balance that becomes increasingly rare in the ensuing months.
In September, the humidity in Sintra, Portugal registers at 67%, marking a slight increase from the summer months of July and August, which both hover around 60%. As the transition from the heat of summer to the cooler embrace of autumn begins, this uptick hints at the lingering warmth and moisture before the more significant autumnal rains emerge. Notably, the humidity starts to trend upwards toward the fall, with October’s reading climbing back to 74%. Sintra's humid climate illustrates a rhythmic pattern—beginning the year with high levels of moisture and gradually declining through the summer before inching upwards again in September—creating a lush, vibrant environment cherished by both locals and visitors alike.
As September rolls into Sintra, Portugal, the UV Index remains high at 8, classified as very high, which necessitates caution during sun exposure. This month follows a summer peak, where the UV Index reached its maximum at 11 in June, showcasing a gradual decline yet still indicating strong sun intensity. With a burn time of just 15 minutes, sun protection measures are essential, echoing the trends observed in the preceding months of July and August, where circulation of high UV levels persisted. As autumn approaches, the UV Index does begin to decrease further into the year—dropping to 6 in October—painting a picture of the shifting solar landscape in Sintra. To learn more and plan your sun safety, check out the Sintra UV Index.
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September in Sintra, Portugal, offers a delightful continuation of summer with 348 hours of sunshine, ensuring that the warmth lingers just a bit longer before autumn sets in. As the months progress from January's 183 hours to July’s peak of 420 hours, there's a visible trend of increasing sunlight that culminates in the vibrant energy of late summer. While August dips slightly to 395 hours, September maintains a robust glow, making it the perfect time to explore Sintra's lush landscapes and historic palaces. As the days grow shorter and the sun begins to retreat towards winter, the allure of September remains strong, inviting visitors to bask in the residual warmth of the season.
In September, Sintra, Portugal enjoys a 66% chance of sunny weather, maintaining the summer's vibrant charm as the season transitions into autumn. This likelihood mirrors the previous months of July and August, known for their warmth and sunshine, suggesting that visitors can still expect pleasant, bright days. As the year progresses into October, the chance of sunshine dips slightly to 55%, indicating the gradual shift towards cooler, more unpredictable weather. Overall, September stands out as a favorable time to bask in Sintra's natural beauty, with an excellent balance of warmth and sunshine before the fall sets in.
As summer draws to a close in Sintra, Portugal, September ushers in a gentle transition, with daylight lasting approximately 12 hours. This marks a subtle decrease from the sun-drenched months of July and August, both boasting 14 hours of daylight. The gradual waning of daylight is a part of the rhythm of the seasons; it starts off with the promise of longer days in spring, peaking in summer before gracefully shifting to shorter days in autumn. After September, daylight continues to decline, forecasting the cozy embrace of fall with its 11 hours in October and further down to just 9 hours by December. This ebb and flow of light not only paints the landscape with varying hues but also invites a sense of reflection and preparation for the changing season ahead.
As September sweeps into Sintra, Portugal, the winds ease slightly, averaging 5.4 m/s (12 mph), a gentle respite compared to the peak summer gusts. This month marks a noticeable decline from the more vigorous 7.3 m/s (16 mph) seen in June and July, signaling the transition towards milder autumn conditions. Following a summer of invigorating breezes, September provides a soft embrace, inviting visitors to explore the breathtaking landscapes without the overpowering winds. As temperatures begin to cool, the calming winds of early fall create an enchanting atmosphere for leisurely strolls through Sintra's stunning parks and historic palaces.
The weather in Sintra changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Sintra and find detailed weather information for every month.
September and January present stark contrasts in weather. In September, temperatures are milder, ranging from a minimum of 15°C (60°F) to a maximum of 23°C (74°F), with an average of 18°C (65°F). It typically sees just a couple of rainy days and lower humidity at 67%. In comparison, January brings cooler temperatures, with a minimum of 7°C (45°F) and an average of 13°C (56°F), peaking at 18°C (64°F). This month experiences more rainfall, averaging 42 mm (1.7 in) over about seven days, along with increased humidity at 85%. For more detailed information about January weather, check this link: Sintra weather in January.
September and February showcase contrasting climates. In September, temperatures are milder, with a minimum of 15°C and a comfortable average of 18°C, peaking at 23°C. The month experiences relatively low precipitation, averaging just 32 mm over only 2 days, coupled with a humidity level of 67%. In stark contrast, February is cooler, with a minimum temperature of 9°C and an average of 13°C, reaching a maximum of 17°C. This month records higher precipitation at 59 mm over 8 days, along with increased humidity at 75%. For more detailed insights, check out Sintra weather in February.
In comparing the weather of September and March, September tends to be warmer with temperatures averaging around 18°C (65°F) and a maximum of 23°C (74°F). In contrast, March is cooler, with an average temperature of 14°C (57°F) and a maximum of 19°C (66°F). Precipitation levels also differ significantly; September experiences only 32 mm (1.2 in) over 2 days, whereas March sees a wetter climate with 64 mm (2.5 in) across 8 days. Humidity is slightly higher in March at 72% compared to September's 67%. For more details on March weather specifics, you can visit Sintra weather in March.
When comparing the weather in September and April, September typically offers milder conditions with an average temperature around 18°C (65°F) and only 32 mm (1.2 in) of precipitation over just 2 days. In contrast, April shows cooler temperatures with an average of 14°C (58°F) and significantly higher precipitation levels of 71 mm (2.8 in) spread across 11 days. Despite both months exhibiting similar humidity levels—67% in September and 70% in April—the difference in rainfall and temperature creates a distinct seasonal contrast. For more specifics on April weather, check Sintra weather in April.
In comparing the weather of September and May, both months exhibit mild temperatures, but September tends to be warmer overall. September has an average temperature of 18°C (65°F), peaking at 23°C (74°F), while May's average is slightly lower at 16°C (61°F), with a maximum of 24°C (76°F). Rainfall is similar, with September receiving 32 mm (1.2 in) over 2 days and May having 33 mm (1.3 in) across 3 days. Humidity levels are comparable as well, with September at 67% and May at 70%, creating comfortable conditions for outdoor activities. For more details, visit Sintra weather in May.
In comparing the weather between September and June, we observe that both months exhibit mild temperatures, but September tends to be slightly warmer. September's average temperature reaches 18°C (65°F), peaking at 23°C (74°F), while June's average is a bit lower at 17°C (63°F), with a maximum of 22°C (72°F). Additionally, September experiences more precipitation, totaling 32 mm (1.2 in) over two days, compared to June's 12 mm (0.5 in) across the same number of rainy days. Humidity levels are also slightly higher in September at 67%, compared to 63% in June. For more detailed information on June weather, you can visit Sintra weather in June.
In comparing the weather between September and July, September typically offers slightly warmer temperatures, with a minimum of 15°C (60°F) and a maximum of 23°C (74°F), while July features a minimum of 16°C (60°F) and a maximum of 21°C (70°F). Both months share a similar average temperature of around 18°C (64-65°F). However, September experiences more precipitation, with 32 mm (1.2 in) occurring over 2 days, contrasted with July's minimal 3 mm (0.1 in) over no rainy days. Additionally, September's humidity is slightly higher at 67%, compared to July's 60%. For more detailed information, you can check Sintra weather in July.
In comparing the weather of September and August, we see that both months have similar average temperatures, settling around 18°C (65°F) with maximums peaking at 23°C (74°F). However, September experiences slightly cooler minimum temperatures, with a low of 15°C (60°F) compared to August's 16°C (61°F). Notably, September is wetter, receiving 32 mm (1.2 in) of precipitation over 2 days, while August is relatively dry with only 4 mm (0.1 in) over 1 day. Additionally, humidity levels increase in September to 67%, compared to 60% in August. For detailed weather insights, you can check out Sintra weather in August.
September typically enjoys milder temperatures, with a minimum of 15°C (60°F) and an average of 18°C (65°F), making it quite comfortable for outdoor activities. Although it experiences only 32 mm (1.2 in) of precipitation over just 2 days, humidity levels are moderate at 67%.
In contrast, October sees a drop in minimum temperatures to 11°C (52°F), while maintaining the same maximum temperature of 23°C (74°F). The month is wetter, with precipitation rising to 53 mm (2.1 in) spread across 6 days, and humidity levels also increase to 74%. This shift makes October feel cooler and more damp compared to September. For more detailed information, you can check Sintra weather in October.
In September, the weather is generally warmer with average temperatures ranging from a minimum of 15°C (60°F) to a maximum of 23°C (74°F). The month experiences relatively low precipitation, totaling 32 mm (1.2 in) over just 2 days, and maintains a humidity level of 67%. In contrast, November brings cooler temperatures, with averages between 11°C (53°F) and 20°C (68°F). This month also sees a significant increase in precipitation, with 89 mm (3.5 in) falling over 11 days, and humidity rising to 83%. For more details on November weather specifics, check Sintra weather in November.
September and December present contrasting weather patterns. In September, temperatures are generally mild, with a minimum of 15°C (60°F) and an average of 18°C (65°F), reaching a pleasant maximum of 23°C (74°F). Precipitation is relatively low, with only 32 mm (1.2 in) over about 2 days, and humidity is moderate at 67%. In stark contrast, December experiences cooler temperatures, with a minimum of 9°C (49°F) and an average of 14°C (58°F), peaking at 17°C (63°F). This month also sees increased rainfall, totaling 73 mm (2.9 in) over approximately 10 days, along with higher humidity levels at 85%. For more details on the December climate in Sintra, you can check Sintra weather in December.
As September arrives in Sintra, the weather begins to transition towards the milder embrace of autumn, offering a delightful reprieve from the summer heat. With an average temperature that comfortably nestles around 18°C (65°F), the month enjoys pleasantly warm days while the evenings cool down just enough for a light jacket. Unlike the peak summer months, September sees a significant drop in both temperature extremes and rainfall, with only a couple of brief, refreshing showers adding to the lush landscape. The humidity gently settles at around 67%, creating a crisp yet comfortable atmosphere that invites exploration of Sintra's enchanting sights. For a deeper understanding of how September's climate enriches your visit, be sure to check out Sintra Climate.