Last updated: August 21, 2025
In December, Alajuela, Costa Rica, showcases a delightful blend of warmth and occasional rain, characterized by a maximum temperature of 26°C (80°F) and a comforting average of 20°C (68°F). Visitors can expect cooler evenings with minimum temperatures dipping to 15°C (58°F). The month brings about 63 mm (2.5 in) of rainfall over approximately 11 days, resulting in a humidity level of 72% that adds a refreshing touch to the air. Ideal for exploring the vibrant landscapes, December weather in Alajuela invites travelers to enjoy the beauty of Costa Rica while embracing the seasonal charm.
In December, Alajuela, Costa Rica, experiences a mild and pleasant climate that sets the stage for the dry season. With minimum temperatures dipping to around 15°C (58°F) and maximums reaching up to 26°C (80°F), the weather is comfortably warm, making it an ideal month for outdoor activities. The average temperature remains stable at 20°C (68°F), much like the preceding months, highlighting the region's relatively consistent climate. As December transitions into the new year, visitors can expect a delightful blend of sunshine and refreshing breezes, perfect for exploring the vibrant surroundings or enjoying the festive atmosphere.
In December, Alajuela experiences a noticeable shift in its precipitation patterns, with rainfall totaling 63 mm (2.5 in) over 11 days. This decline comes after the region's wettest months, where October alone records an impressive 570 mm (22.4 in). Compared to the heavy downpours of the previous months, December's milder precipitation indicates a transition towards the dry season. While the frequency of rain decreases, the month still retains a vigorous tropical feel as the lush landscapes surrounding Alajuela remain vibrant and alive, setting the stage for a beautiful start to the new year.
December in Alajuela, Costa Rica, marks a notable shift in humidity as it settles at 72%, providing a refreshing conclusion to the wetter months. Following the peak humidity levels of 84% in June and 85% in July, the atmosphere gradually begins to dry out, with December's figures reflecting a steady decrease from the humid summer. As the year transitions from November's high of 80%, December's humidity still retains a sense of moisture, typical of Central American climates, yet allows for a more comfortable experience. This trend highlights a gradual return to drier conditions as the region prepares for the drier season ahead, with humidity levels stabilizing throughout the year, generally hovering around the mid to high 60s and low 70s.
In December, Alajuela experiences a notable decrease in the UV Index, dropping to 10, which falls within the very high exposure category. This is a slight decline from the extreme levels seen in the earlier months, where UV Index readings consistently hovered between 12 and 15, resulting in a burn time of just 10 minutes. The change in December allows for a slightly extended burn time of 15 minutes, offering a bit more leeway for sun lovers. However, caution is still advised, as the UV Index remains high. As you enjoy the sunny days in this vibrant region, remember to protect your skin—especially at midday when the sun is at its strongest. For more insights on UV exposure, check out Alajuela UV Index.
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In December, Alajuela, Costa Rica, basks in an impressive 291 hours of sunshine, seamlessly continuing its annual trend of abundant sunlight. Positioned just before the dawn of the dry season, this month showcases a delightful transition from the cooler, rainier months of November and October, which recorded 229 and 211 hours respectively. Interestingly, December's sunshine hours are a significant contrast to the cloudier patterns seen in the mid-year, especially in June and July, which dropped to their lowest with only 226 and 209 hours. As the year wraps up, December not only serves as a precursor to the sun-drenched months of January and February—boasting 249 and 296 hours—but also highlights the vibrancy of Costa Rican life, making it an ideal time for visitors to revel in the warm glow and natural beauty that the region offers.
In December, Alajuela, Costa Rica, enjoys a 50% chance of sunny weather, making it a delightful time for visitors seeking warmth and light. This month sees a slight uptick in sunshine compared to the rainy season that peaks from May to October, where chances of sunny days plummet to as low as 6% in August. Transitioning from November's 27% probability, December offers a promising balance as the dry season approaches. This trend of increasing sunshine reaffirms Alajuela's appeal as a vibrant destination, inviting travelers to bask in its charm during the festive end-of-year celebrations.
In Alajuela, Costa Rica, the rhythm of daylight plays a significant role in marking the seasons. December, with its 11 hours of daylight, reflects the city's shift from the longer days of mid-year to the shorter days typical of the end of the year. This reduction in daylight, echoed in January and February, contrasts with the 12 hours enjoyed from March through September, showcasing a consistent trend of increased sunshine during the heart of the dry season. As the year progresses, daylight begins to wane again in October and November, wrapping up a cycle that beautifully highlights Alajuela's tropical climate and its gentle transition through the months.
As December arrives in Alajuela, Costa Rica, the winds start to pick up ever so slightly, with average speeds reaching 2.1 m/s (5 mph). This marks a subtle rebound from the calmer months of October and November, which see lower wind velocities at 1.1 m/s (2 mph) and 1.7 m/s (4 mph), respectively. Notably, the trend throughout the year reveals a gradual decline in wind speed during the wet season, particularly from May to August, where it dips as low as 1.1 m/s (3 mph). However, as the year draws to a close, the winds begin to regain vigor, suggesting a refreshing shift that complements the vibrant atmosphere of the holiday season in Central Valley. This seasonal variation epitomizes the dynamic climate of Alajuela, highlighting the region's unique allure as the year comes to an end.
Weather in Alajuela varies notably across the year, with each month offering distinct climate conditions. This page compares December’s weather to other months in Alajuela, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of December and January, we see some notable differences. December generally experiences slightly warmer nights with a minimum temperature of 15°C (58°F), while January's nights are cooler, with a minimum of 13°C (56°F). Both months have an average temperature of 20°C (68°F), but January can reach a maximum of 27°C (82°F), compared to December’s maximum of 26°C (80°F). Precipitation also differs significantly; December sees more rain with 63 mm (2.5 in) over 11 days, while January has only 32 mm (1.3 in) over 6 days, leading to a lower humidity of 68% in January compared to December's 72%. For more detailed information, visit Alajuela weather in January.
In December, the weather is generally mild, with temperatures ranging from a minimum of 15°C (58°F) to a maximum of 26°C (80°F) and an average of 20°C (68°F). This month experiences a fair amount of precipitation, totaling 63 mm (2.5 in) over approximately 11 days, coupled with a humidity level of 72%.
In contrast, February offers slightly warmer temperatures, with a minimum of 13°C (56°F) and a maximum of 28°C (83°F), while maintaining a similar average of 20°C (69°F). Notably, February sees significantly less rainfall, totaling just 13 mm (0.5 in) over about 3 days, and a decrease in humidity to 68%. For more details, check out Alajuela weather in February.
In December, the weather is generally warm, with temperatures ranging from a minimum of 15°C (58°F) to a maximum of 26°C (80°F) and an average of 20°C (68°F). This month sees relatively higher humidity levels at 72% and experiences more rainfall, with about 63 mm (2.5 inches) of precipitation over 11 days. In contrast, March offers slightly warmer conditions, with temperatures ranging from a minimum of 14°C (57°F) to a maximum of 28°C (83°F) and an average of 21°C (70°F). Precipitation drops significantly in March to 15 mm (0.6 inches) spread over just 4 days, along with a decrease in humidity to 66%. For more details on March's weather, you can visit Alajuela weather in March.
In December, the weather is generally warm with temperatures ranging from a minimum of 15°C (58°F) to a maximum of 26°C (80°F), averaging around 20°C (68°F). The month experiences relatively moderate rainfall, totaling 63 mm (2.5 in) over about 11 days, and the humidity sits at 72%, creating a humid atmosphere. In contrast, April sees slightly higher temperatures, with minimums still at 15°C (58°F) but averaging 21°C (70°F) and peaking at 29°C (85°F). However, it also has more precipitation, totaling 79 mm (3.1 in) across 16 days, while the humidity decreases slightly to 67%. For more detailed information, check out Alajuela weather in April.
When comparing the weather in December and May, some notable differences emerge. December generally boasts milder temperatures, with a minimum of 15°C (58°F) and a maximum of 26°C (80°F), while May sees slightly warmer conditions, with temperatures ranging from a minimum of 16°C (61°F) to a maximum of 28°C (83°F). However, May is significantly wetter, with precipitation totaling 391 mm (15.4 in) over 27 days, compared to December's 63 mm (2.5 in) spread across 11 days. Humidity levels remain relatively similar, with December at 72% and May slightly lower at 69%. For more detailed insights, you can refer to Alajuela weather in May.
When comparing the weather in December and June, we see notable differences in temperatures and precipitation levels. December features mild temperatures ranging from a minimum of 15°C (58°F) to a maximum of 26°C (80°F), with an average of 20°C (68°F). The month receives about 63 mm (2.5 in) of precipitation over 11 days and has a humidity level of 72%. In contrast, June experiences slightly warmer temperatures, with a minimum of 16°C (60°F) and a maximum of 27°C (81°F), averaging 21°C (70°F). However, June is significantly wetter, with around 351 mm (13.8 in) of rain spread across 27 days, and higher humidity at 84%. For more details, check Alajuela weather in June.
In December, the weather is generally warm with average temperatures ranging from a minimum of 15°C (58°F) to a maximum of 26°C (80°F). The month experiences moderate precipitation of 63 mm (2.5 in) over about 11 days, accompanied by a humidity level of 72%. In contrast, July tends to be more humid and wetter, with an average temperature slightly higher, peaking at 27°C (81°F) and a minimum of 16°C (61°F). Rainfall in July significantly increases to 233 mm (9.2 in) over 26 days, resulting in a higher humidity of 85%. For more detailed insights on this month's weather, you can explore Alajuela weather in July.
December and August offer contrasting weather patterns. In December, temperatures range from a minimum of 15°C (58°F) to a maximum of 26°C (80°F), with an average of around 20°C (68°F). Precipitation is relatively moderate at 63 mm (2.5 in) over 11 days, accompanied by a humidity level of 72%. In contrast, August sees slightly warmer temperatures, with minimums of 16°C (60°F) and maximums reaching up to 28°C (82°F), while maintaining the same average of 20°C (69°F). However, August experiences significantly higher rainfall, totaling 331 mm (13.0 in) over 26 days, and a higher humidity level of 82%. For more details about August weather, you can check Alajuela weather in August.
When comparing the weather in December and September, it’s clear that both months have similar temperature ranges, with December's minimum temperature at 15°C and maximum at 26°C, while September’s max temperature is slightly higher at 27°C. However, September experiences significantly more rainfall, totaling 436 mm over 28 days, compared to December's much lighter precipitation of 63 mm over just 11 days. Additionally, humidity levels are slightly higher in September at 81%, compared to December's 72%. For more detailed information on September weather, you can check Alajuela weather in September.
In comparing the weather between October and December, both months feature similar average temperatures, hovering around 20°C (68°F). However, December experiences slightly warmer highs with a maximum of 26°C (80°F), whereas October peaks at 27°C (80°F). October is significantly wetter, with precipitation reaching 570 mm (22.4 in) over 29 days, compared to December's 63 mm (2.5 in) over just 11 days. The humidity remains high in both months, but October has a slightly elevated humidity level at 80%, compared to December's 72%. For a more detailed look at October weather in Alajuela, visit Alajuela weather in October.
In comparing the weather between November and December, we see some notable differences. Both months share similar temperature ranges, with minimums around 15°C (58°F), average temperatures at 20°C (68°F), and maximums peaking at 26°C (80°F). However, December experiences significantly less precipitation, totaling 63 mm (2.5 in) over 11 days, compared to November's 209 mm (8.2 in) over 19 days. This results in December being drier and slightly less humid, with an average humidity of 72% compared to November's 80%. For more detailed information about the climate during this period, you can check Alajuela weather in November.
In December, Alajuela experiences a distinct shift in its weather patterns, characterized by cooler temperatures compared to the sweltering months that precede it. With an average of 20°C, the pleasant climate offers a refreshing respite, making it an inviting time for outdoor activities. However, December also marks the beginning of the rainy season, bringing a noticeable increase in precipitation days, as the landscape transforms under a veil of lush greenery. While humidity remains relatively high, the overall conditions create a unique and vibrant atmosphere in Alajuela, perfect for travelers seeking to embrace the beauty of Costa Rica. For a deeper understanding of how December stacks against the rest of the year, check out the detailed information on Alajuela Climate.