Last updated: August 21, 2025
In Atenas, Costa Rica, December offers a delightful tropical climate, characterized by a maximum temperature of 30°C (86°F) and an average of 23°C (74°F), creating a warm and inviting atmosphere. Nights are pleasantly cool, with temperatures dipping to a minimum of 18°C (65°F). However, December is also marked by frequent rainfall, accumulating to 72 mm (2.8 in) over 18 days, leading to a humidity level of 72% that enhances the lush beauty of this region. Visitors can expect a blend of warm sunny days interspersed with refreshing showers, making it an ideal time to experience the vibrant landscape and rich culture of Atenas.
In December, Atenas, Costa Rica experiences a delightful blend of warmth and mildness, aligning with the region's characteristic tropical climate. With average temperatures hovering around 23°C (74°F), the month sees minimums of 18°C (65°F) and maximums reaching up to 30°C (86°F). This pattern follows the trend of previous months, presenting a subtle increase in daytime heat while maintaining pleasant nighttime coolness. As the year winds down, December brings ideal conditions for outdoor adventures and exploring the lush landscapes, making it a perfect time for visitors to enjoy the vibrant flora and the welcoming atmosphere of this charming town.
In Atenas, Costa Rica, December marks a shift towards drier conditions as the year winds down. With precipitation totaling 72 mm (2.8 in) over 18 rainy days, December experiences significantly less rainfall compared to the peak wet months of September and October, which average over 600 mm. This gradual decrease indicates a transition away from the intense rainfall of the rainy season, as the year sees a return to lighter showers, reminiscent of earlier months like January and February. While December still offers moisture, the overall trend illustrates a move towards milder weather, paving the way for the drier season ahead.
In December, Atenas, Costa Rica experiences a moderate humidity level of 72%, providing a pleasant end to the year. As the months transition from the dry season in early year—with humidity levels hovering around 66% to 69%—the environment shifts towards a more humid climate starting in June, peaking at 85% in July. This gradual rise in humidity continues through the interstitial months of August and September, but by December, the atmosphere becomes notably more comfortable compared to the humid summer months. With its lush greenery and vibrant landscapes, December's humidity invites visitors to embrace the lingering warmth of the rainy season while enjoying the serene beauty that Costa Rica is renowned for.
In December, Atenas, Costa Rica, experiences a slight decrease in UV Index to 10, categorizing it as very high and extending the burn time to 15 minutes. This marks a transition from the extreme UV levels maintained throughout the earlier months, where indices fluctuated between 12 and 15, typically demanding protection within just 10 minutes of sun exposure. As the year concludes, while the UV intensity eases, it's crucial to remain vigilant against sunburn. Always check the Atenas UV Index for the latest updates and stay sun-smart throughout the festive season.
UV Risk Categories
December in Atenas, Costa Rica, shines with an impressive 291 hours of sunlight, making it a splendid time for outdoor adventures and relaxation. As the year wraps up, sunlight hours show a remarkable rebound from the low of 209 hours in July, steadily climbing as the months progress. After a dip in the wet season, both November and December offer a delightful finish, with December's hours nearing the peak of 329 in March. This trend highlights the transition from the lush, green rainy season, creating a vibrant backdrop for visitors and locals alike to soak in the bright Costa Rican sun before the new year begins.
In Atenas, Costa Rica, December offers a promising chance of sunshine, boasting a 56% probability of clear skies. This month marks a slight uptick from the preceding November, which holds a 31% likelihood, signaling a transition towards sunnier weather as the year draws to a close. As we look through the year, January stands out with a 57% chance of sunshine, suggesting that December's weather foreshadows the bright conditions to come. This trend highlights a noticeable drop in sunny days during the wet months of April through August, where the chances plummet to single digits. December, with its favorable odds, invites both locals and visitors to revel in the beauty of this vibrant time in Atenas, making it an ideal month for outdoor activities and appreciation of the lush landscape.
In Atenas, Costa Rica, daylight duration showcases a captivating rhythm throughout the year. Starting with 11 hours of daylight in both January and February, the days gradually lengthen to a peak of 12 hours from March through September. This consistent duration creates a delightful stretch of daylight ideal for exploration and outdoor activities. As the year transitions to October, the daylight dips back to 11 hours, a trend that continues into November and December, marking the return to shorter days. This cyclical pattern not only underscores the region's tropical climate but also enhances the charm of Atenas, making every month uniquely bright and inviting.
As December unfolds in Atenas, Costa Rica, the atmosphere begins to shift slightly, with wind speeds reaching an average of 1.6 m/s (4 mph). This marks a subtle uptick from the calmer months of October and November, where winds occasionally flirted with single digits, averaging 1.4 m/s (3 mph) and 1.1 m/s (2 mph), respectively. Throughout the year, the winds are generally mild, peaking in the spring with a slight high of 2.1 m/s (5 mph) in March. The gentle breezes of December signal a tranquil transition towards the year-end, inviting everyone to enjoy the fresh air amid the lush landscapes. This seasonal shift not only enhances the scenic beauty but also provides a refreshing comfort as holiday festivities begin to fill the air.
Weather in Atenas varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Atenas, focusing on differences in temperature, rainfall, humidity, and UV levels.
December and January in Atenas exhibit relatively mild and similar temperatures overall, with December experiencing slightly warmer highs and a minimum temperature of 18°C (65°F) compared to January’s 17°C (63°F). However, January typically boasts a drier climate, with only 28 mm (1.1 in) of precipitation over 7 days, in stark contrast to December's 72 mm (2.8 in) spread across 18 days. Additionally, January has a marginally lower humidity level at 68%, compared to December’s 72%. For more details, you can check Atenas weather in January.
In December, the weather in Atenas is characterized by warmer temperatures, with a minimum of 18°C (65°F) and an average of 23°C (74°F), reaching a maximum of 30°C (86°F). This month also experiences higher precipitation, totaling 72 mm (2.8 in) spread over 18 days, resulting in a humidity level of 72%. In contrast, February sees slightly cooler temperatures, with a minimum of 16°C (62°F) and an average of 24°C (76°F), peaking at 31°C (88°F). Significantly less rainfall occurs in February, with only 13 mm (0.5 in) over 3 days, and humidity drops to 68%. For more detailed information, you can visit Atenas weather in February.
When comparing the weather in December and March, we notice some distinct differences. December experiences milder temperatures, with averages around 23°C (74°F) and maximums reaching 30°C (86°F). However, it also sees higher precipitation, with about 72 mm (2.8 in) of rain over 18 days, resulting in a humidity level of 72%. In contrast, March tends to be warmer with an average temperature of 25°C (77°F) and maximums peaking at 32°C (89°F). Rainfall in March is considerably less, with only 18 mm (0.7 in) over just 4 days, and the humidity drops slightly to 66%. For more detailed information, you can check Atenas weather in March.
The weather in December and April presents some notable differences and similarities. In December, temperatures range from a minimum of 18°C (65°F) to a maximum of 30°C (86°F), with an average of 23°C (74°F) and 72 mm (2.8 in) of precipitation over 18 days. The humidity is relatively high at 72%. In contrast, April sees slightly warmer temperatures, with a minimum of 18°C (64°F) and a maximum of 31°C (89°F), averaging 24°C (76°F). However, rainfall is more significant in April, totaling 118 mm (4.6 in) over 24 days, while humidity drops to 67%. For more detailed information about the weather in April, you can check Atenas weather in April.
When comparing the weather in December and May, both months experience similar maximum temperatures, peaking at 30°C (86°F). However, December tends to feel slightly warmer on average with temperatures ranging from a minimum of 18°C (65°F) to an average of 23°C (74°F), while May sees a minimum of 19°C (67°F) and an average of 24°C (75°F). Notably, May is significantly wetter, with a staggering 412 mm (16.2 in) of precipitation over 30 days, compared to December's 72 mm (2.8 in) spread over 18 days. Humidity levels are also similar, hovering around 69% in May and reaching 72% in December. For a more detailed look at the weather patterns in May, you can check Atenas weather in May.
In December, the weather in Atenas features a warm range of temperatures, with a minimum of 18°C (65°F), an average of 23°C (74°F), and a maximum of 30°C (86°F). The month experiences moderate precipitation at 72 mm (2.8 in) over approximately 18 days, with humidity levels at 72%.
In contrast, June sees slightly warmer temperatures, with a minimum of 19°C (66°F) and an average of 24°C (75°F), maintaining a peak of 30°C (86°F). However, it is significantly wetter, receiving 397 mm (15.6 in) of rain across 30 days and higher humidity at 84%.
For a detailed overview of conditions, you can explore Atenas weather in June.
December and July exhibit notable differences in weather patterns. In December, temperatures range from a minimum of 18°C (65°F) to a maximum of 30°C (86°F), with an average of 23°C (74°F). This month experiences approximately 72 mm (2.8 in) of precipitation over 18 days, with humidity around 72%. In contrast, July sees slightly warmer temperatures, with a minimum of 19°C (67°F) and a maximum of 29°C (85°F), averaging 24°C (75°F). However, July is significantly wetter, receiving 296 mm (11.7 in) of rainfall over 30 days and a higher humidity level of 85%. For more details about July weather, you can check Atenas weather in July.
December and August in Atenas present distinct weather patterns despite similar average temperatures. In December, temperatures range from a minimum of 18°C to a maximum of 30°C, accompanied by a moderate 72 mm of rainfall over 18 days, resulting in a humidity level of 72%. In contrast, August sees slightly warmer mornings with a minimum of 19°C, but it is characterized by significantly heavier rainfall, totaling 393 mm across 30 days, leading to a higher humidity level of 82%. For more detailed information, check out Atenas weather in August.
In December, the weather in Atenas features a pleasant range of temperatures with a minimum of 18°C (65°F), averaging around 23°C (74°F), and reaching a maximum of 30°C (86°F). Precipitation is relatively low at 72 mm (2.8 in) over 18 days, with humidity levels at 72%. In contrast, September experiences similar minimum and average temperatures but has a slightly cooler maximum of 29°C (85°F). Rainfall is significantly higher in September, with 461 mm (18.2 in) spread over 29 days, contributing to a higher humidity level of 81%. For more detailed insights into the weather patterns, you can explore Atenas weather in September.
In comparing the weather between December and October, both months experience similar minimum and average temperatures, with December slightly warmer on average. December sees maximum temperatures reach 30°C (86°F), while October reaches up to 29°C (84°F). However, October is significantly wetter, with 639 mm (25.2 in) of precipitation spread over 30 days, compared to December's 72 mm (2.8 in) over just 18 days. Additionally, October has a higher humidity level at 80% compared to December's 72%. For a closer look at October's weather specifics, you can visit Atenas weather in October.
In comparing the weather between November and December, both months showcase similar temperature ranges, with minimums around 18°C (64-65°F), averages at 23°C (74°F), and maximums only slightly differing—29°C (85°F) in November and 30°C (86°F) in December. However, December experiences significantly less precipitation, totaling 72 mm (2.8 in) over just 18 days, compared to November’s 251 mm (9.9 in) spread across 28 days. Additionally, humidity levels are slightly lower in December at 72%, while November sees a higher average humidity of 80%. For more detailed information, check Atenas weather in November.
As December unfolds in Atenas, a noticeable shift in weather emerges compared to previous months. This time of year experiences warmer days and cooler nights, with an average temperature that invites both comfort and mildness. While precipitation increases, bringing about a lush greenery as the rainy season wraps up, the humidity remains high, creating a tropical atmosphere. This blend of warm temperatures and humidity can feel quite different from the drier months earlier in the year. If you're planning to visit, embrace the mix of sunshine and rain that defines this enchanting time in Atenas. For more insights on the overall weather patterns, check out Atenas Climate.