December Weather in Sintra, Portugal

Last updated: February 24, 2025

Experience the enchanting December weather in Sintra, Portugal, where average temperatures hover around 14°C (58°F), with maximums reaching 17°C (63°F) and minimums dipping to a cool 9°C (49°F). This month, Sintra sees about 73 mm (2.9 in) of rainfall over 10 days, adding a refreshing touch to the picturesque landscapes. With humidity levels around 85%, the air is crisp yet invigorating, making it an ideal time to explore the region’s stunning palaces and lush gardens. Embrace the charm of Sintra in December, where each rainy day enhances the vibrant greenery and mystical atmosphere.

December Temperature in Sintra

In December, Sintra, Portugal experiences a mild winter, with temperatures ranging from a minimum of 9°C (49°F) to a comfortable maximum of 17°C (63°F). The average temperature hovers around 14°C (58°F), making it a pleasant time for visitors to explore the region's stunning architecture and lush landscapes. As the year draws to a close, the temperatures gradually decline from the warmer months, yet they remain relatively gentle compared to harsher winter climates elsewhere. This trend of mild winters is characteristic of Sintra, inviting travelers to enjoy outdoor activities amid the enchanting scenery without the bite of severe cold.

December Weather in Sintra: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in Sintra, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends.
JanFebMarAprMayJunJulAugSepOctNovDec555657586163646465646058
Data source: Temperature data for Sintra generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Sintra

In December, Sintra experiences a notable uptick in precipitation, with 73 mm (approximately 2.9 inches) of rain falling over about 10 days. This marks a slight decrease compared to November's significant rainfall of 89 mm spread over the same number of days. The month's precipitation is a reminder of the region's mild, wet winters, transitioning from the dryer summer months where rainfall drops to a mere 3 mm in July. As autumn gives way to winter, these rainy days contribute to the lush greenery that Sintra is famed for, setting a picturesque scene just in time for the holiday season.

December Precipitation Trends in Sintra

The chart displays monthly precipitation patterns in Sintra, with values for each month alongside December's data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how December's conditions compare to those of other months.
JanFebMarAprMayJunJulAugSepOctNovDec4259647133123432538973
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
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December Humidity in Sintra

In Sintra, Portugal, December marks a return to heightened humidity levels, mirroring January's 85% humidity. This month stands out as a transitional period following the gradual decline seen throughout the summer, where humidity reaches its lowest at 60% in July and August. As autumn progresses, moisture levels rise again, peaking in November at 83% before stabilizing in December. This cyclical pattern highlights Sintra's humid climate, emphasizing the dampness that envelops the region during the winter months, perfect for those who appreciate the lush greenery that thrives in such conditions.

December Average Humidity in Sintra

This chart illustrates the average monthly humidity levels in Sintra, with December's data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, allowing you to see how December's humidity levels compare to other months.
JanFebMarAprMayJunJulAugSepOctNovDec85%75%72%70%70%63%60%60%68%74%83%85%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in Sintra

In December, Sintra, Portugal experiences a UV Index of 3, categorizing it as moderate with a burn time of 30 minutes. This marks a gentle decline from the intense summer months, where indices peaked at 11 in June, indicating extreme exposure. As the year winds down, the UV effects diminish, but it's still wise to remain cautious during midday sun. Both January and February follow suit with similar indices, maintaining a moderate level of exposure. Overall, this trend reflects a seasonal shift, suggesting that while the need for sun protection decreases, vigilance remains important year-round. For a detailed look at Sintra's UV trends, check out Sintra UV Index.

Maximum UV Index Levels in Sintra for December

The chart shows the monthly maximum UV Index (UVI) for Sintra in December, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues.
JanFebMarAprMayJunJulAugSepOctNovDec356910111098643
Data source: Sintra December UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

December Sunshine in Sintra

In December, Sintra, Portugal, sees a gentle retreat of sunlight, totaling around 224 hours. This marks a subtle decline from the vibrant peak of August, which boasts 395 hours. As autumn gives way to winter, December's daylight is a reminder of the region's seasonal rhythm, where shorter days invite a sense of tranquility. Interestingly, though December experiences less sunshine than its predecessors, it still shines brighter than the early months of the year, such as January with just 183 hours. The trend demonstrates a gradual build-up of daylight from the cold of winter to the blossoming warmth of spring, making Sintra's December a perfect time for cozy exploration amid the backdrop of its stunning landscapes.

Monthly Sunshine Duration in Sintra: December Highlighted

The December sunshine duration represents the total number of hours Sintra experiences direct sunlight during the month of December, excluding cloudy or obstructed periods. This chart compares the sunshine duration of December with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec183h231h307h351h405h409h420h395h348h313h236h224h
Data source: Sintra December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Sintra During December

December in Sintra, Portugal, offers a less favorable chance of sunny weather compared to the bustling summer months. With a 39% likelihood of sunshine, this month trails behind others like March (60%) and June (65%) when the sun shines brighter and more consistently. Interestingly, while autumn months like November boast a more optimistic 65%, December tends to welcome winter’s chill, causing a noticeable dip in sunny days. As the year winds down, visitors can expect a cozy, albeit cloudier atmosphere, encouraging a more introspective experience of Sintra's enchanting landscapes.

Percentage of Sunny Days in December in Sintra

The chart illustrates the percentage of sunny days in Sintra throughout the year, with December highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Sintra experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec45%24%60%41%57%65%69%66%66%55%65%39%
Data source: Sintra December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Sintra in December

As December rolls into Sintra, Portugal, daylight starts to retreat, offering just nine hours of sunlight—a trend that mirrors the slow descent into winter. Following a crescendo of brightness in the late spring and summer months, where the sun graced the sky for up to 14 hours, December brings a gentle reminder of nature's cycles. This decreasing trend underscores the contrast of the shortened days compared to earlier months, while still inviting the charm of a cozy winter atmosphere filled with twinkling lights and festive spirit. As the year draws to a close, the rhythm of daylight invites a time for reflection and warmth, setting the stage for the eventual return of longer days ahead.

Average Daylight Hours in Sintra for December

The chart illustrates the variation in daylight duration in Sintra throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec9h 46m10h 44m11h 58m13h 14m14h 17m14h 49m14h 32m13h 36m12h 23m11h 8m10h 2m9h 28m
Data source: Sintra daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Sintra

In December, the winds in Sintra, Portugal continue to sweep through with an average speed of 6.7 m/s (15 mph), showcasing a pattern of relative consistency as the year closes. Notably, this month's wind speed is comparable to the highs of January and February, which both recorded the same breezy pace. Throughout the year, we observe a seasonally dynamic trend: wind speeds peak during the late spring and summer months, with May and June holding the title for the strongest gusts at 7.3 m/s (16 mph). As the seasons shift, the winds gradually mellow from April’s 4.9 m/s (11 mph) to a gentle 5.1 m/s (11 mph) in October, before regaining strength in the colder months. This harmonious flow of wind contributes to Sintra's enchanting atmosphere, making the year-round coastal charm enticing for all who visit.

Average December Wind Speed in Sintra

The chart displays monthly wind speed patterns in Sintra, with values for each month shown alongside December's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how December's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec6.96.96.04.97.37.37.26.45.45.16.56.7 m/s
Data source: Sintra December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Sintra Compares to Other Months

The weather in Sintra changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of December'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.

December and January exhibit similar humid conditions, with both months maintaining an average humidity of 85%. December typically experiences slightly warmer temperatures, ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), while January's temperatures dip slightly, with a minimum of 7°C (45°F) and a maximum of 18°C (64°F). In terms of precipitation, December is wetter with 73 mm (2.9 in) over 10 days, compared to January's 42 mm (1.7 in) spread over just 7 days. For more details on January's weather, visit Sintra weather in January.

December and February in Sintra showcase mild winter weather, yet they exhibit some nuanced differences. December has a slightly higher average temperature of 14°C (58°F) compared to February's 13°C (56°F), although both months experience a minimum of around 9°C (48°F to 49°F). Precipitation is also higher in December, with 73 mm (2.9 in) falling over 10 days, whereas February sees less rain, at 59 mm (2.3 in) across 8 days. Additionally, February boasts lower humidity levels at 75%, compared to the 85% humidity typical of December. For more detailed information about weather conditions in February, check out Sintra weather in February.

In December, the weather typically sees a minimum temperature of 9°C (49°F) and an average of 14°C (58°F), with a maximum reaching 17°C (63°F). This month experiences about 73 mm (2.9 in) of precipitation over approximately 10 days, accompanied by high humidity levels averaging 85%. In contrast, March offers similar minimum temperatures but with a slightly warmer average of 14°C (57°F) and a higher maximum of 19°C (66°F). Precipitation decreases to 64 mm (2.5 in) over about 8 days, and humidity also drops to 72%. For more detailed insights into the weather conditions during March, you can visit Sintra weather in March.

In comparing the weather of December and April, we see some notable similarities and differences. Both months have an average temperature of 14°C (58°F), but December features a slightly cooler range with minimum temperatures dropping to 9°C (49°F) compared to April's minimum of 10°C (50°F). April experiences more warmth overall, reaching a maximum of 21°C (71°F), while December peaks at 17°C (63°F). Precipitation is quite similar, with December recording 73 mm (2.9 in) over 10 days, while April sees 71 mm (2.8 in) across 11 days, indicating a slightly wetter month. Additionally, humidity levels are higher in December at 85%, compared to April's more comfortable 70%. For a more detailed look at weather conditions during April, you can explore Sintra weather in April.

In December, the weather tends to be cooler, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F). The month is characterized by higher humidity at 85% and more frequent rain, averaging 73 mm (2.9 in) over about 10 days. In contrast, May brings warmer temperatures, with minimums of 11°C (53°F) and maximums reaching 24°C (76°F). Precipitation is significantly reduced to just 33 mm (1.3 in) across only 3 days, and humidity levels drop to a more comfortable 70%. For more specific details on the conditions in May, you can check Sintra weather in May.

December and June exhibit notable differences in weather characteristics. In December, temperatures range from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), with an average of 14°C (58°F). The month sees a significant amount of precipitation, totaling 73 mm (2.9 in) over about 10 days and 85% humidity, creating a damp and cool atmosphere. In contrast, June experiences warmer temperatures, with a minimum of 14°C (58°F) and a maximum reaching 22°C (72°F), averaging around 17°C (63°F). Rainfall is minimal, with only 12 mm (0.5 in) over just 2 days, and humidity drops to a more comfortable 63%. For more details, you can check Sintra weather in June.

December and July offer stark contrasts in weather conditions. In December, temperatures range from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), with an average of 14°C (58°F). This month is also characterized by high humidity levels at 85% and significant precipitation, receiving about 73 mm (2.9 in) over approximately 10 days, making it a relatively wet period. In contrast, July boasts milder temperatures, with a minimum of 16°C (60°F) and a maximum of 21°C (70°F), averaging around 18°C (64°F). It experiences a much drier climate with only 3 mm (0.1 in) of precipitation, typically spread across zero rainy days and a lower humidity level of 60%. This makes July an ideal month for outdoor activities—more details can be found here: Sintra weather in July.

In December, temperatures in Sintra range from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), with an average of 14°C (58°F). The month is characterized by higher humidity at 85% and significant precipitation, averaging 73 mm (2.9 in) over about 10 days. In contrast, August offers warmer weather, with temperatures starting at a minimum of 16°C (61°F) and peaking at 23°C (74°F), averaging 18°C (65°F). This month experiences much lower precipitation, with only 4 mm (0.1 in) falling over just 1 day, and humidity levels are more comfortable at 60%. For more details on the weather during this pleasant summer month, check Sintra weather in August.

In comparing the weather between December and September, we find notable differences in both temperature and precipitation. December experiences cooler temperatures, with a minimum of 9°C (49°F) and an average of 14°C (58°F), while September boasts warmer conditions, with a minimum of 15°C (60°F) and an average of 18°C (65°F). Additionally, December sees significantly higher precipitation at 73 mm (2.9 in) over about 10 days, compared to September's milder 32 mm (1.2 in) over only 2 days. Humidity levels in December are also higher at 85%, compared to September's 67%. For more details, check out Sintra weather in September.

In comparing the weather between October and December, we notice a significant drop in temperatures as December exhibits a minimum of 9°C (49°F) and an average of 14°C (58°F), whereas October's temperatures range from a minimum of 11°C (52°F) to an average of 18°C (64°F) and can peak at 23°C (74°F). Additionally, December experiences more precipitation, with 73 mm (2.9 in) over 10 days, in contrast to October's 53 mm (2.1 in) over just 6 days. The humidity also rises in December, averaging 85%, compared to 74% in October. For more detailed insights about October weather, visit Sintra weather in October.

In December, temperatures tend to be slightly lower, with minimums around 9°C (49°F) and an average of 14°C (58°F), compared to November's higher minimum of 11°C (53°F) and average of 16°C (60°F). While both months experience a fair amount of rainfall, December has 73 mm (2.9 in) over 10 days, slightly less than November's 89 mm (3.5 in) across 11 days. Humidity levels remain high in both months, with December at 85% and November at 83%. For a more detailed look at weather conditions in November, check out Sintra weather in November.

Compare Sintra's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Sintra

As December rolls into Sintra, the weather transforms into a cooler, cozy climate, offering a delightful contrast to the warmer months. With average temperatures hovering around a mild 14°C (58°F), residents and visitors alike can expect a refreshing escape from the summer heat. However, this month also brings increased precipitation, marked by frequent drizzles that contribute to the region's lush landscape. The humidity lingers at a significant 85%, adding to the enchanting atmosphere of this historic town. For those looking to explore Sintra's breathtaking sights, warm layers and an umbrella might just be essential companions. To delve deeper into Sintra's unique weather patterns throughout the year, visit Sintra Climate.