December Weather in San Jose, Costa Rica

Last updated: August 21, 2025

December in San Jose, Costa Rica offers a delightful climate characterized by mild temperatures and a touch of humidity. With daytime highs reaching a comfortable 24°C (75°F) and nightly lows dipping to around 12°C (55°F), this month provides a pleasant average of 18°C (64°F). Visitors can expect a fair amount of precipitation, totaling 156 mm (6.1 in) over approximately 16 days, contributing to the lush landscapes for which the region is renowned. The average humidity of 72% adds a refreshing quality to the air, making December an ideal time to explore the vibrant surroundings and enjoy the lush greenery that flourishes during this rainy season.

December Temperature in San Jose

As December blankets San Jose, Costa Rica, the temperatures reflect a delightful shift towards the cooler end of the spectrum. With nighttime lows settling around 12°C (55°F) and daytime highs reaching a comfortable 24°C (75°F), the month maintains an average temperature of 18°C (64°F). This marks a slight dip from the warmer months preceding it, yet still offers a pleasant climate for outdoor adventures and festive activities. The transition is evident as December ushers in a refreshing breeze, inviting both locals and visitors to bask in the vibrant atmosphere of this enchanting city. While the temperatures may cool slightly, the warmth of Costa Rican hospitality remains unwavering, making December a charming time to explore San Jose.

December Weather in San Jose: Daily Temperature Highs, Lows, and Averages

The chart illustrates December temperature patterns in San Jose, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In San Jose, December typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec636364666666666666656564
Data source: Temperature data for San Jose 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 San Jose

In December, San Jose, Costa Rica experiences moderately high precipitation, with 156 mm (6.1 in) of rain falling over 16 days. This month marks a notable shift from the heavy rains of the preceding months, particularly October's peak of 517 mm, signaling a gradual transition into the drier season. Compared to the intense downpours of May and June, where rainfall exceeded 400 mm and typically drown the region, December offers a respite, yet it holds onto a significant amount of moisture that nourishes the lush surroundings. As the year closes, the overall precipitation decreases, reflecting the changing patterns as San Jose welcomes the sunny days of January ahead.

December Precipitation Trends in San Jose

The chart displays monthly precipitation patterns in San Jose, 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. In San Jose, December typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec934349113425341266304380517260156
Data source: Precipitation data for December generated using information from the Copernicus Climate Change Service.
Choose your preferred precipitation unit

December Humidity in San Jose

December in San Jose, Costa Rica, marks a transition in humidity levels, registering at 72%. This is a slight decrease from the peak months of June and July, where humidity soared to a humid 84% and 85% respectively. Following a trend seen in the latter part of the year, December's conditions reflect a calming down from the intense moisture prevalent during the rainy season. Despite this moderation, the humidity remains relatively high compared to the earlier months, like January and February, which both sit at a steadier 68%. Overall, December presents a balanced blend of humidity, making it a comfortable time to experience the vibrant atmosphere of San Jose while still enjoying the lingering tropical essence.

December Average Humidity in San Jose

This chart illustrates the average monthly humidity levels in San Jose, with December’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In December, average humidity in San Jose is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec68%68%66%67%69%84%85%82%81%80%80%73%
Data source: Humidity data for December generated using information from the Copernicus Climate Change Service.

December UV Index in San Jose

In December, San Jose, Costa Rica experiences a UV Index of 11, indicative of an extreme exposure category with a burn time of just 10 minutes. This marks a slight decrease from the peak of 16 in April, yet throughout the year, the region consistently showcases high UV levels, making sun protection a priority. From January to March, the UV Index steadily climbs to a maximum of 15, maintaining an extreme classification that persists across most months. The trend highlights the region's year-round intensity of sunlight, reinforcing the importance of awareness and precautions for both locals and visitors. For more details on UV levels throughout the year, visit San Jose UV Index.

Maximum UV Index Levels in San Jose for December

The chart shows the monthly maximum UV Index (UVI) for San Jose 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. In December, the maximum UV index in San Jose typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec121415161414141414151211
Data source: San Jose 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 San Jose

December in San Jose, Costa Rica, basks in 289 hours of sunshine, offering a warm farewell to the year. This month bridges the gap between the sunshine-filled days of summer and the quieter times of rainy season that follow. When compared to the other months, December maintains a robust level of sunshine, especially when contrasted with the rainy months of June and July, which see lower totals of 244 and 229 hours, respectively. While January kicks off the year with an impressive 246 hours, December shines brightly with its generous hours, inviting residents and visitors alike to enjoy the tropical splendor before the clouds roll in. As the year closes, the consistent warmth and light experienced in December not only uplifts spirits but sets a hopeful tone for the sun-kissed days ahead.

Monthly Sunshine Duration in San Jose: December Highlighted

The December sunshine duration represents the total number of hours San Jose 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.
JanFebMarAprMayJunJulAugSepOctNovDec246h297h329h303h248h244h229h236h249h234h247h289h
Data source: San Jose December Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in San Jose During December

When considering the likelihood of sunny weather in December in San Jose, Costa Rica, you'll find that this month offers a respectable 43% chance of sunshine. This statistic is notable as it falls just below the sunny highs of January at 47%, indicating that December can still be a delightful time to enjoy the outdoors. As the rainy season winds down, potential visitors can expect a gradual increase in sunny days, especially when compared to the markedly lower chances in the subsequent months of April and May, which plummet to around 12-16%. In fact, December’s weather offers a pleasant transition, bridging the gap between the diminishing rainfall of November (22%) and the brighter days that follow in the new year, making it an attractive option for sun seekers.

Percentage of Sunny Days in December in San Jose

The chart illustrates the percentage of sunny days in San Jose 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 San Jose experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec47%42%40%16%12%13%16%6%9%13%22%43%
Data source: San Jose December chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in San Jose in December

In San Jose, Costa Rica, daylight duration experiences subtle yet noticeable shifts throughout the year. During the initial months of the year—January and February—the city enjoys approximately 11 hours of daylight. As spring approaches in March, the days begin to lengthen, reaching up to 12 hours and remaining consistent through the summer months. This prolonged daylight continues until October, when it gradually tapers back to 11 hours, echoing the patterns seen at the year's start. The twilight of November and December marks a return to shorter days, reinforcing the rhythm of nature’s cycle in this vibrant locale. Overall, the daylight trends highlight a delightful balance of consistent illumination that captures the essence of San Jose's tropical climate.

Average Daylight Hours in San Jose for December

The chart illustrates the variation in daylight duration in San Jose throughout the year, with December highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec11h 36m11h 47m12h 3m12h 20m12h 34m12h 41m12h 37m12h 25m12h 9m11h 52m11h 39m11h 32m
Data source: San Jose daylight hours, calculated by summing the hours between sunrise and sunset for each day.

December Winds in San Jose

As December sets in, San Jose, Costa Rica experiences a gentle increase in wind speed, averaging 2.2 m/s (5 mph). This uptick follows a trend observed in the early months of the year, where the wind typically whips through the city at similar speeds. Notably, the winds become notably calmer during the rainy season from May to October, dipping to around 1.1 m/s (3 mph) in October. However, as the rainy season recedes and the festive spirit of December approaches, conditions shift, bringing a refreshing breeze that hints at the vibrancy of the holiday season. Overall, December’s winds serve as a pleasant reminder of the dynamic climate of this beautiful Central American locale.

Average December Wind Speed in San Jose

The chart displays monthly wind speed patterns in San Jose, 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.
JanFebMarAprMayJunJulAugSepOctNovDec2.42.12.31.71.61.31.61.21.31.11.82.2 m/s
Data source: San Jose December wind data, generated using information from the Copernicus Climate Change Service.

How December Weather in San Jose Compares to Other Months

Weather in San Jose varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in San Jose, focusing on differences in temperature, rainfall, humidity, and UV levels.

In December, the weather tends to be slightly warmer, with average temperatures ranging from a minimum of 12°C (55°F) to a maximum of 24°C (75°F), accompanied by higher precipitation of 156 mm (6.1 in) over 16 days, resulting in a humidity level of 72%. In contrast, January sees a minor drop in temperatures, with an average ranging from 11°C (53°F) to 24°C (76°F), as well as a reduction in rainfall to 93 mm (3.7 in) over 11 days and a slightly lower humidity of 68%. For more details about the weather in January, visit San Jose weather in January.

In comparing the weather between December and February, we see some notable differences. December boasts a slightly higher average temperature of 18°C (64°F), with a maximum of 24°C (75°F) and a minimum of 12°C (55°F). However, it also experiences significantly more rainfall, with 156 mm (6.1 in) of precipitation spread over 16 days, resulting in a humidity level of 72%. In contrast, February exhibits milder conditions with a similar average temperature of 17°C (64°F) but a slightly higher maximum of 25°C (78°F) and a minimum of 11°C (52°F). Precipitation drops drastically to 43 mm (1.7 in) over just 12 days, leading to lower humidity at 68%. For more details on weather conditions during this month, you can check out San Jose weather in February.

In comparing the weather between December and March, December tends to be slightly warmer overall, with average temperatures reaching 18°C (64°F) and maximums of 24°C (75°F). Precipitation is notably higher in December, with 156 mm (6.1 in) over 16 days, resulting in a more humid atmosphere at 72%. In contrast, March experiences similar average temperatures but with a maximum of 25°C (76°F). Precipitation in March is significantly lower at 49 mm (1.9 in) across 14 days, contributing to a drier and less humid environment, with humidity levels at 66%. For more details, check out San Jose weather in March.

When comparing the weather in December and April, notable differences emerge. December experiences slightly cooler temperatures, with averages ranging from a minimum of 12°C (55°F) to a maximum of 24°C (75°F), while April boasts a warmer average, featuring a minimum of 13°C (56°F) and a maximum of 26°C (80°F). Additionally, December sees more precipitation, with a total of 156 mm (6.1 in) spread over 16 days, compared to April's 113 mm (4.4 in) over 23 days. Despite higher rainfall in April, the humidity is slightly lower at 67% compared to December’s 72%. For more details about the April weather, you can visit San Jose weather in April.

December and May present contrasting weather patterns. December typically features milder temperatures, with a minimum of 12°C (55°F) and a maximum of 24°C (75°F), while May sees slightly warmer conditions, reaching a minimum of 14°C (58°F) and a maximum of 26°C (79°F). However, May is significantly wetter, experiencing 425 mm (16.7 in) of precipitation over 29 days compared to December's 156 mm (6.1 in) across 16 days. Despite higher humidity levels in December at 72%, May maintains a comfortable humidity level of 69%. For a closer look at weather specifics in May, you can refer to San Jose weather in May.

In December, the weather in San Jose features a mild temperature range with a minimum of 12°C (55°F) and a maximum of 24°C (75°F), while the average temperature sits at around 18°C (64°F). The month experiences notable precipitation, totaling 156 mm (6.1 in) over 16 days, with humidity levels at 72%. In contrast, June sees slightly warmer temperatures, with a minimum of 15°C (59°F) and a maximum of 26°C (78°F), averaging 19°C (67°F). However, it is also significantly wetter, with total rainfall reaching 341 mm (13.4 in) over 28 days and higher humidity at 84%. For more detailed insights, check out San Jose weather in June.

In comparing December and July weather, December tends to be milder with average temperatures ranging from 12°C (55°F) to 24°C (75°F), while July maintains a slightly warmer range of 15°C (59°F) to 25°C (77°F). Precipitation is notably higher in July, with 266 mm (10.5 in) spread over 28 days compared to December's 156 mm (6.1 in) over 16 days. Additionally, July experiences higher humidity at 85%, compared to December's 72%. For more detailed insights on July weather, visit San Jose weather in July.

In December, the weather is generally mild with temperatures ranging from a minimum of 12°C (55°F) to a maximum of 24°C (75°F), offering an average temperature of 18°C (64°F). The month sees significant rainfall, totaling 156 mm (6.1 in) over approximately 16 days, accompanied by a humidity level of 72%. In contrast, August experiences slightly warmer conditions, with temperatures ranging from a minimum of 15°C (59°F) to a maximum of 26°C (79°F) and an average of 19°C (66°F). However, August is notably wetter, with 304 mm (12.0 in) of rain spread over 28 days, resulting in a higher humidity level of 82%. This comparison highlights December's relatively drier and cooler weather compared to the wetter and warmer conditions of August. For more detailed information, visit San Jose weather in August.

In comparing the weather of December and September, we can see some notable differences. December tends to be slightly warmer, with minimum temperatures averaging at 12°C (55°F) compared to September's 14°C (58°F). The average daytime temperature in both months is fairly similar, with December averaging 18°C (64°F) and September at 19°C (66°F). However, September experiences significantly more rainfall, accumulating 379 mm (14.9 in) over 29 days, whereas December receives only 156 mm (6.1 in) across 16 rainy days. Additionally, humidity levels are higher in September at 81%, compared to December's 72%. For more detailed information, you can check San Jose weather in September.

In comparing the weather between December and October, we observe a slight increase in average temperatures in October, with minimum temperatures at 14°C (58°F) compared to December's 12°C (55°F) and maximums reaching up to 25°C (78°F) versus December's 24°C (75°F). However, October is significantly wetter, with 517 mm (20.4 in) of precipitation over 29 days, while December experiences less rainfall at 156 mm (6.1 in) across 16 days. Humidity levels are also higher in October, averaging 80% compared to December's 72%. For more detailed insights, you can explore San Jose weather in October.

In comparing December and November weather, both months display similar temperature ranges, with December's minimum temperature slightly lower at 12°C (55°F) compared to November's 14°C (57°F). The average temperature remains consistent at around 18°C (64°F). However, December experiences significantly less precipitation, totaling 156 mm (6.1 in) over 16 days, while November sees a much higher rainfall of 260 mm (10.3 in) over 24 days. Additionally, December's humidity is slightly lower at 72%, compared to November's 80%. For more detailed insights, you can check San Jose weather in November.

Compare San Jose's Climate with Cities Worldwide

Conclusion: What to Expect From December Weather in San Jose

As December unfolds in San Jose, the weather exhibits a distinct character compared to the rest of the year. The temperatures are generally mild, with a comfortable average that makes outdoor activities enjoyable, even as daytime highs approach a warm 24°C. However, this month also brings increased rainfall, with nearly half the month experiencing some precipitation, leading to a more humid atmosphere. This shift not only enhances the lushness of the surrounding landscapes but also adds a refreshing coolness that is a welcome contrast to the drier months. For those interested in a more detailed exploration of the city's weather patterns, check out San Jose Climate.