Last updated: August 27, 2025
Arenal, Peru experiences a warm and humid January, with temperatures peaking at 34°C (94°F) and averaging around 25°C (78°F). Nights offer a mild respite, as temperatures dip to a comfortable 19°C (66°F). The region witnesses minimal precipitation, with only 10 mm (0.4 in) of rain recorded over just 3 days. The humidity remains high at 89%, contributing to a lush, vibrant landscape that is characteristic of Arenal’s tropical climate. This combination of warmth and moisture creates an inviting atmosphere, perfect for exploring the breathtaking natural beauty that surrounds this charming destination.
In January, Arenal, Peru, welcomes the New Year with delightful temperatures that set the stage for outdoor adventures. With daytime highs peaking at a warm 34°C (94°F) and pleasant averages around 25°C (78°F), the climate is ripe for exploration. Nights are comfortably mild, dropping to a minimum of 19°C (66°F). As the month progresses into February, temperatures remain relatively stable, with minima rising slightly to 20°C (68°F) and averages reaching 26°C (80°F). This trend continues into March, where a gradual increase nudges averages to 27°C (80°F) and maxima to 35°C (95°F). As the year moves into April and beyond, a cooling trend begins, particularly noticeable by July and August, when temperatures dip to a refreshing 15°C (59°F) at night. Throughout the year, Arenal experiences a unique rhythm of warmth and coolness, making it an enticing destination for those seeking both serene and energetic experiences in nature.
In January, Arenal, Peru, experiences relatively low precipitation, with only 10 mm (0.4 in) of rain over a mere 3 days. This marks the beginning of the year with drier conditions, especially compared to February, which sees a significant uptick in rainfall to 42 mm (1.7 in) over 6 days. As the months progress, March becomes the wettest, receiving 93 mm (3.7 in) across 8 days, highlighting a clear trend towards increased moisture in early spring. Interestingly, precipitation drops sharply again in the following months, with May, June, and July recording minimal levels, indicating a distinct dry season. Overall, January sets the stage for a more dynamic weather pattern in the months ahead, transitioning from refreshing rains to a pronounced dry spell.
In January, Arenal, Peru, experiences a high humidity level of 89%, setting the stage for the lush, vibrant environment the region is known for. This peak in humidity gradually decreases slightly in the following months, with February and March maintaining a steady 87%, while April sees a minor drop to 86%. The peak return in May again raises humidity levels to 89%, a testament to the region's tropical climate. As the year progresses into the drier months of June and July, humidity levels dip significantly to 84% and 71%, respectively. Interestingly, humidity levels begin to recover slightly by September, reaching 75%, and continue to rise again in the latter months, closing the year with December at 86%. This ebb and flow of humidity not only shapes Arenal's unique ecosystem but also influences the experiences of those who visit this breathtaking destination throughout the year.
In January, Arenal, Peru experiences a remarkable UV Index of 14, categorizing it as extreme, which means you can get sunburned in just 10 minutes of unprotected exposure. This high level of solar intensity continues throughout the first quarter of the year, peaking in March with a UV Index of 16 before slightly subsiding to 15 in April and back to 13 in May. As the year progresses into the cooler months, the UV Index begins to decline slowly, yet it remains in the extreme category, hovering between 11 and 13 from June through December. With consistent caution advised, it’s essential to protect your skin year-round. For detailed insights on the UV Index trends in Arenal, you can visit Arenal UV Index.
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In January, Arenal, Peru, embraces the year with a generous 275 hours of sunshine, setting a bright tone for the months ahead. As the days progress into February, the sunshine climbs to 302 hours, revealing a promising trend that continues to strengthen through March at 317 hours. By April, the sun shines even brighter with 324 hours, peaking in May at 334 hours. A fascinating rhythm emerges as the sunshine remains abundant through the summer and into fall, with hours stabilizing around the mid-300s, peaking at 345 hours in December. This steady increase not only highlights Arenal’s radiant climate but also invites adventure seekers to bask in its delightful warmth throughout the year.
In Arenal, Peru, the likelihood of sunny weather in January stands at a moderate 31%, mirroring the chance expected in February. As the months progress, this figure experiences a notable shift, with sunshine becoming more prevalent in April at 39%, leading into the drier months of May and July, where the chances soar to 63% and 56%, respectively. While early in the year, the potential for sunny days remains somewhat limited, it steadily increases, peaking during the dry season and suggesting a transition towards more favorable weather conditions as summer approaches. Thus, those planning a visit can anticipate a gradual rise in sunshine as January gives way to the warmer months ahead.
In Arenal, Peru, the enchanting rhythm of daylight follows a predictable pattern throughout the year. As January unfolds, residents and visitors alike enjoy a generous 12 hours of daylight, a trend that beautifully persists through February and March, creating an inviting atmosphere for exploration and adventure. However, as April arrives, daylight begins to shift slightly down to 11 hours, remaining consistent through the mid-year months of May, June, July, and August. This subtle reduction offers a cozy, intimate ambiance ideal for experiencing Arenal's lush landscapes. Interestingly, as the year progresses towards September, daylight extends back to 12 hours, continuing through October, November, and December, once again embracing the warmth and vibrancy of this stunning destination. This cyclical dance of daylight not only highlights Arenal's diverse beauty but also signifies the natural transitions of the seasons.
In January, Arenal, Peru experiences a gentle average wind speed of 3.3 m/s (7 mph), setting a tranquil tone for the month. As the year progresses, the winds demonstrate a notable trend of gradually increasing strength, peaking at 4.0 m/s (9 mph) in October. February and April maintain a steady pace with 3.4 m/s (8 mph), while March dips slightly to 2.7 m/s (6 mph), providing a brief calm before the air currents pick up again in the following months. Overall, the wind speeds remain relatively mild throughout the year, with a sense of gradual increase and stability that contributes to Arenal’s enchanting climate.
Weather in Arenal varies notably across the year, with each month offering distinct climate conditions. This page compares January’s weather to other months in Arenal, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather between January and February, we see a slight increase in temperature, with February averaging 26°C (80°F) compared to January's 25°C (78°F). Both months experience maximum temperatures of 34°C (94°F), but January has a lower minimum temperature of 19°C (66°F) compared to February's 20°C (68°F). Precipitation in February is notably higher, measuring 42 mm (1.7 in) over six days, in contrast to January's lighter rainfall of 10 mm (0.4 in) across three days. Humidity remains relatively high in both months, with February slightly less humid at 87% compared to January's 89%. For a more detailed look at February weather specifics, check out Arenal weather in February.
In January, the weather is characterized by a warm climate, with minimum temperatures around 19°C (66°F) and averaging 25°C (78°F). Precipitation is relatively low at 10 mm (0.4 in) over only three days, and humidity stands at a high 89%. In contrast, March sees slightly warmer conditions, with minimum temperatures rising to 21°C (69°F) and an average of 27°C (80°F). However, the month is significantly wetter, receiving 93 mm (3.7 in) of rain over eight days, and maintaining a similar humidity level of 87%. For a thorough look at the weather in March, you can visit Arenal weather in March.
In comparing the weather between January and April, we see that both months exhibit similar temperature ranges, with January having a minimum of 19°C (66°F) and a maximum of 34°C (94°F), while April maintains a slightly lower minimum of 18°C (65°F). The average temperature remains consistent at 25°C (78°F) for both months. However, April experiences increased precipitation, with 19 mm (0.8 in) compared to January's 10 mm (0.4 in), though both months see a similar number of rainy days; January has 3 days while April sees just 2. Humidity levels are slightly lower in April at 86% compared to January's 89%. For more detailed insights into the weather patterns, you can check Arenal weather in April.
In January, the weather is typically warmer with temperatures ranging from a minimum of 19°C (66°F) to a maximum of 34°C (94°F), averaging around 25°C (78°F). The month receives about 10 mm (0.4 in) of precipitation over approximately 3 days, while the humidity remains consistently high at 89%. In contrast, May experiences slightly cooler temperatures, with a minimum of 16°C (62°F) and a maximum of 32°C (91°F), averaging 23°C (74°F). Precipitation is lower in May, measuring 6 mm (0.2 in) over just 2 days, but the humidity stays the same at 89%. For more detailed information, you can check Arenal weather in May.
In January, the weather is notably warmer with temperatures ranging from a minimum of 19°C (66°F) to a maximum of 34°C (94°F) and an average of 25°C (78°F). The month sees some precipitation, with 10 mm (0.4 in) spread over 3 days and humidity levels at a high 89%. In contrast, June experiences milder temperatures, with a range from 17°C (63°F) to a maximum of 31°C (87°F) and an average of 22°C (71°F). There is little to no rainfall in June, recording only 2 mm (0.1 in) and 0 days of precipitation, along with lower humidity at 84%. For more insights on the Arenal climate, check out Arenal weather in June.
January and July present contrasting weather conditions. In January, temperatures range from a minimum of 19°C (66°F) to a maximum of 34°C (94°F), with an average temperature of 25°C (78°F). The month experiences higher humidity at 89%, along with some precipitation, totaling 10 mm (0.4 in) over three days. In contrast, July offers cooler weather, where temperatures fluctuate between a minimum of 16°C (60°F) and a maximum of 27°C (82°F), with an average of just 20°C (69°F). Notably, July is much drier, with only 1 mm (0.1 in) of precipitation over zero days and reduced humidity at 71%. For more details about the weather during this month, you can check Arenal weather in July.
January and August present contrasting weather conditions. In January, temperatures range from a minimum of 19°C (66°F) to a maximum of 34°C (94°F), with an average of 25°C (78°F). This month also sees higher humidity at 89% and moderate precipitation with 10 mm (0.4 in) over three days. In sharp contrast, August experiences cooler temperatures, with a minimum of 15°C (59°F) and a maximum of 27°C (82°F), averaging just 20°C (68°F). This month is notably drier, featuring only 1 mm of precipitation and no rainy days, alongside a more comfortable humidity level of 71%. For more details on how the weather unfolds in August, check Arenal weather in August.
In January, the weather is notably warmer with temperatures ranging from a minimum of 19°C (66°F) to a maximum of 34°C (94°F), accompanied by high humidity levels at 89%. This month also experiences some precipitation, with an average of 10 mm (0.4 in) over three days. In contrast, September cools down significantly, featuring a minimum of 15°C (60°F) and a maximum of 28°C (83°F), and a much lower humidity of 75%. Remarkably, September is dry, receiving only 1 mm (0.1 in) of precipitation across zero days. For more details on the weather patterns in September, check out Arenal weather in September.
When comparing the weather in January and October, notable differences emerge. January experiences warmer temperatures, with an average of 25°C (78°F) and maximums reaching up to 34°C (94°F), while October has a cooler average of 21°C (70°F) and maximums peaking at 29°C (85°F). In terms of precipitation, January sees more rainfall—10 mm (0.4 in) over three days—compared to October, which has minimal precipitation of just 4 mm (0.1 in) and no rainy days. Additionally, January's humidity is higher at 89%, contrasting with the more comfortable 77% humidity of October. For more details, you can check Arenal weather in October.
January and November present distinct weather patterns. In January, temperatures range from a minimum of 19°C (66°F) to a maximum of 34°C (94°F), with an average of 25°C (78°F). The month experiences relatively high humidity at 89% and receives about 10 mm (0.4 in) of rainfall over three days. In contrast, November offers slightly cooler conditions, with temperatures ranging from a minimum of 15°C (59°F) to a maximum of 30°C (86°F), having a lower average of 21°C (70°F). Rainfall is minimal in November, totaling just 5 mm (0.2 in) over one day, accompanied by a reduced humidity level of 79%. For more details, you can read about Arenal weather in November.
January generally features slightly warmer temperatures compared to December, with minimums around 19°C (66°F) and maximums reaching up to 34°C (94°F). In contrast, December experiences a milder range, with lows of 17°C (64°F) and highs of 32°C (89°F). Precipitation is somewhat lower in January at 10 mm (0.4 in) over three days, whereas December sees slightly more rain at 16 mm (0.6 in) for the same number of days. Humidity levels remain high in both months, with January at 89% and December slightly lower at 86%. For more detailed insights into December weather, check out Arenal weather in December.
January in Arenal showcases a vibrant climate, characterized by warm temperatures and high humidity, creating ideal conditions for lush vegetation and vibrant landscapes. While the thermometer often reaches its peak, the average warmth remains comfortable, making outdoor activities particularly enjoyable. With only a few days of light precipitation, January stands out as a month that balances sunshine with the occasional refreshing shower, differing from the wetter months ahead. For those looking to explore the rich biodiversity of the region, this makes January an alluring time to visit. For more insights on the weather trends throughout the year, check out Arenal Climate.