December Weather in Cascais, Portugal

Last updated: February 24, 2025

In Cascais, Portugal, December presents a mild escape into the winter season, with maximum temperatures reaching around 17°C (63°F) and an average of 14°C (58°F). The city experiences a cooler minimum temperature of 9°C (49°F), creating a cozy atmosphere for locals and visitors alike. With approximately 73 mm (2.9 in) of rain over 10 days, be prepared for occasional showers while enjoying the vibrant coastal scenery. The high humidity level of 85% lends a refreshing feel to the air, enhancing the charm of this beautiful destination. Whether exploring local attractions or relaxing by the sea, December in Cascais offers a unique blend of mild weather and cultural richness.

December Temperature in Cascais

As December wraps Cascais in its cool embrace, the temperatures reflect a gentle shift toward winter. With minimums dipping to 9°C (49°F) and an average of 14°C (58°F), it’s a time for cozy layered outfits. While the maximum temperature reaches a mild 17°C (63°F), the overall climate invites leisurely strolls through the charming coastal scenery. Compared to the milder months of late autumn, December showcases a subtle drop, yet maintains a pleasant atmosphere perfect for exploring the town’s vibrant culture and scenic beaches. This transitional month offers a unique blend of crisp air and warmth that captivates both residents and visitors alike.

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

The chart illustrates December temperature patterns in Cascais, 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 Cascais generated using information from the Copernicus Climate Change Service.
Choose your preferred temperature unit
The average of daily temperatures (24 hours) calculated across all days in the month.

December Precipitation in Cascais

December in Cascais, Portugal marks a transition into winter with a notable increase in precipitation. With an average of 73 mm (2.9 in) over approximately 10 rainy days, it showcases a consistent wetness that follows November's heavier rainfall of 89 mm. This trend indicates a significant uptick in precipitation as the year winds down, setting the stage for the rainy season ahead. Interestingly, while November usually delivers the most rain, December maintains a robust level of moisture, showcasing the region's capacity for sustained wet weather. In comparison to the drier summer months, the rainfall in December underscores Cascais's wetter climate as it heads into the new year.

December Precipitation Trends in Cascais

The chart displays monthly precipitation patterns in Cascais, 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.
Choose your preferred precipitation unit

December Humidity in Cascais

In Cascais, Portugal, December often brings a notable return to elevated humidity levels, reaching 85%—a figure that mirrors the high of January. Throughout the year, humidity tends to decline from a peak in January, with the warmest summer months of July and August showing the lowest figures at 60%. As autumn progresses, humidity levels gradually rise again, with November's 83% serving as a precursor to the damp chill of winter. This seasonal trend highlights a shift from drier summer months to a more humid atmosphere as the year closes, creating a unique blend of climate characteristics in this picturesque coastal town.

December Average Humidity in Cascais

This chart illustrates the average monthly humidity levels in Cascais, 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 Cascais

In Cascais, Portugal, the UV Index showcases noticeable seasonal trends throughout the year. December returns to a moderate UV Index of 3, allowing for a burn time of 30 minutes, similar to conditions in January and November. As winter sets in, both January and December feature lower UV exposure compared to the peak summer months of June, where the index hits an alarming 11—characterized as extreme—and a burn time decreases to just 10 minutes. The transition from cool to warm months reveals a clear ascent in UV levels beginning in late winter through summer, emphasizing the importance of sun protection as the days grow warmer. For more detailed insights on UV levels throughout the year, visit Cascais UV Index.

Maximum UV Index Levels in Cascais for December

The chart shows the monthly maximum UV Index (UVI) for Cascais 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: Cascais 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 Cascais

Cascais, Portugal, enjoys a delightful climate characterized by a gradual increase in sunshine as the year progresses. Starting in January with a modest 183 hours, the days grow longer and brighter, peaking in the summer months of July and August with 420 and 395 hours respectively. As autumn sets in, sunshine hours gently decline, but even in December, the coastal town basks in a respectable 224 hours of sunlight, making it a perfect winter getaway. This trend highlights Cascais as an attractive destination for sun-seekers year-round, where each month brings a tapestry of light that enhances its stunning scenery and vibrant atmosphere.

Monthly Sunshine Duration in Cascais: December Highlighted

The December sunshine duration represents the total number of hours Cascais 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: Cascais December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Cascais During December

In December, the likelihood of sunny weather in Cascais, Portugal takes a dip to 39%, marking it as one of the cloudier months of the year. This decline follows a trend where the chances of sunshine exhibit a gradual upward trajectory from the cooler winter months to the peak summer, with December's probabilities notably lower than the previous month's promising 65%. While early winter may bring less sunshine compared to the sunnier summer months of July and August, which boast nearly 69% and 66% chances respectively, December still offers the allure of milder temperatures, making it a charming destination for those seeking a reprieve from harsher winter conditions elsewhere.

Percentage of Sunny Days in December in Cascais

The chart illustrates the percentage of sunny days in Cascais 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 Cascais experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec45%24%60%41%57%65%69%66%66%55%65%39%
Data source: Cascais December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Cascais in December

In Cascais, Portugal, the daylight duration ebbs and flows throughout the year, creating a rhythmic dance that marks the changing seasons. December, with its 9 hours of daylight, mirrors the shorter days of January and November, as the region transitions into winter. This month marks the culmination of a gradual decrease in daylight that begins in late summer, after June, when the sun graces the skies for a generous 14 hours. As we move from the sun-drenched months of May through July, the light slowly recedes, leaving behind a wistful longing for those longer days. By early spring, the daylight begins its ascent once more, igniting the promise of longer, brighter days ahead. This cyclical pattern not only enhances the beauty of Cascais but also invites residents and visitors alike to engage with the changing landscape in captivating ways.

Average Daylight Hours in Cascais for December

The chart illustrates the variation in daylight duration in Cascais 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: Cascais daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in Cascais

In Cascais, Portugal, the December wind dances gently with an average speed of 6.7 m/s (15 mph), a fitting continuation of the fall’s breezy embrace. Throughout the year, wind speeds exhibit a notable fluctuation, peaking in May and June at 7.3 m/s (16 mph), while the breezes begin to calm as autumn turns to winter. Following a slight dip through the warmer months, November welcomes a revitalized gust, aligning perfectly with December’s average. This trend reveals a subtle yet captivating rhythm of seasonal winds, ensuring that Cascais remains a breezy haven for both locals and visitors alike.

Average December Wind Speed in Cascais

The chart displays monthly wind speed patterns in Cascais, 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: Cascais December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in Cascais Compares to Other Months

The weather in Cascais 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 Cascais and find detailed weather information for every month.

In December, the weather is relatively mild, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F) and an average of 14°C (58°F). The month sees around 73 mm (2.9 in) of precipitation over approximately 10 days, accompanied by high humidity levels of 85%.

In contrast, January brings slightly cooler temperatures, with a minimum of 7°C (45°F), an average of 13°C (56°F), and a maximum of 18°C (64°F). There is less precipitation, totaling 42 mm (1.7 in), occurring over about 7 days, while humidity remains constant at 85%.

For more detailed information, check out Cascais weather in January.

December and February in Cascais exhibit similar temperature ranges, with December averaging 14°C (58°F) and February slightly cooler at 13°C (56°F). Both months experience minimum temperatures around 9°C (49°F) and maximums reaching 17°C (63°F). However, December tends to be wetter, with 73 mm (2.9 in) of precipitation over 10 days, compared to February's 59 mm (2.3 in) over 8 days. Additionally, December is more humid, with humidity levels at 85%, whereas February's humidity drops to 75%. For a more detailed look at February's weather, you can visit Cascais weather in February.

In December, the weather in Cascais features mild temperatures with a minimum of 9°C (49°F), an average of 14°C (58°F), and a maximum reaching 17°C (63°F). This month sees a decent amount of rainfall, with approximately 73 mm (2.9 in) over 10 days, contributing to a high humidity level of 85%.

Contrast this with March, where the temperatures remain similar, with a minimum of 9°C (49°F) and an average of 14°C (57°F), but the maximum climbs slightly to 19°C (66°F). Additionally, March experiences less precipitation at 64 mm (2.5 in) over 8 days and lower humidity at 72%. For more detailed information, you can check out Cascais weather in March.

In December, the weather remains relatively cool with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), accompanied by high humidity levels of 85%. The month sees approximately 73 mm (2.9 in) of precipitation spread over 10 days. In contrast, April experiences a slight increase in minimum temperature to 10°C (50°F), with maximums reaching up to 21°C (71°F), indicating a warmer atmosphere. The average precipitation in April is slightly lower at 71 mm (2.8 in) over 11 days but features lower humidity at 70%. For a more detailed look at weather trends, you can check Cascais weather in April.

In December, the weather is cooler, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F). The month experiences higher humidity at 85% and receives about 73 mm (2.9 in) of precipitation over approximately 10 days. In contrast, May brings milder conditions, featuring temperatures between 11°C (53°F) and 24°C (76°F) and a more pleasant humidity level of 70%. Additionally, May sees significantly less rainfall, with only 33 mm (1.3 in) recorded over just 3 days. For more specific details, you can check out Cascais weather in May.

December and June present a stark contrast in weather conditions. In December, temperatures range from a chilly 9°C (49°F) to a mild 17°C (63°F), with an average of 14°C (58°F). The month sees considerable precipitation, with about 73 mm (2.9 in) falling over 10 days and high humidity levels at 85%. In contrast, June offers warmer temperatures, with minimums around 14°C (58°F) and maximums reaching 22°C (72°F), averaging at 17°C (63°F). Rainfall is scarce during June, totaling only 12 mm (0.5 in) over 2 days, and the humidity drops to a more comfortable 63%. For more detailed information, you can check Cascais weather in June.

December and July showcase a stark contrast in weather. In December, temperatures range from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), accompanied by significant precipitation of 73 mm (2.9 in) over about 10 days. The humidity is notably high at 85%, creating a chilly and damp atmosphere. In contrast, July enjoys warmer conditions with temperatures starting from a minimum of 16°C (60°F) and reaching a pleasant maximum of 21°C (70°F). This summer month is characterized by dry weather, with only 3 mm (0.1 in) of precipitation and no rainy days, alongside a more comfortable humidity level of 60%. For more details, refer to Cascais weather in July.

December and August present 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). The month experiences a higher level of precipitation at 73 mm (2.9 in) over approximately 10 days, coupled with a high humidity level of 85%. Conversely, August showcases warmer weather, with temperatures averaging between 16°C (61°F) and 23°C (74°F) and an overall average of 18°C (65°F). This month is characterized by minimal rainfall of just 4 mm (0.1 in) across only 1 day, and a more comfortable humidity level of 60%. For a deeper insight into August's weather, check out Cascais weather in August.

In comparing the weather between December and September, December is noticeably cooler, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F). In contrast, September enjoys milder conditions, with temperatures typically ranging from 15°C (60°F) to 23°C (74°F). Additionally, December experiences significantly more precipitation, averaging 73 mm (2.9 in) over about 10 days, while September sees much less rainfall at only 32 mm (1.2 in) over just 2 days. Humidity levels are also higher in December, at 85%, compared to September's more comfortable 67%. For more insights into September's weather, you can check Cascais weather in September.

In comparing the weather of December and October, December tends to be cooler, with average temperatures ranging from a minimum of 9°C (49°F) to a maximum of 17°C (63°F), while October boasts milder conditions, with temperatures varying from a minimum of 11°C (52°F) to a maximum of 23°C (74°F). Additionally, October experiences less precipitation, tallying up to 53 mm (2.1 in) over approximately 6 days, compared to December's 73 mm (2.9 in) that falls over about 10 days. The humidity is also higher in December, reaching around 85%, compared to October's 74%. For more detailed insights about the climate during this month, you can visit Cascais weather in October.

In comparing the weather between November and December, December presents slightly cooler temperatures overall, with a minimum of 9°C and an average of 14°C, compared to November's minimum of 11°C and average of 16°C. Additionally, December experiences a reduction in maximum temperatures, peaking at 17°C, while November reaches up to 20°C. Precipitation levels are relatively close, with December receiving 73 mm over 10 days and November totaling 89 mm across 11 days. The humidity is slightly higher in December at 85%, compared to November's 83%. For a detailed look at November's weather, check out Cascais weather in November.

Compare Cascais's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in Cascais

As December unfolds in Cascais, the weather presents a delightful shift from the milder months. With comfortably cool temperatures averaging around 14°C (58°F) and minimums dipping to about 9°C (49°F), it’s a time when layers become your best friend. Rainfall is more frequent, with 73 mm (2.9 in) expected over approximately 10 days, bringing a fresh, crisp atmosphere ideal for cozying up in charming cafés or exploring the coastal beauty. The 85% humidity adds a touch of briskness to the air, making for a refreshing winter experience. Compared to the warmer and drier months, December invites you to enjoy the unique charm of Cascais during the festive season. For more insights into the region's weather patterns, visit Cascais Climate.