Last updated: August 21, 2025
In September, the weather in Liberia, Costa Rica presents a blend of warmth and considerable rainfall. With a maximum temperature of 32°C (90°F) and a comfortable average of 25°C (77°F), days are typically warm and inviting. However, as clouds gather, the area experiences significant precipitation, totaling 319 mm (12.6 in) over approximately 25 days, resulting in an 80% humidity level that enhances the tropical atmosphere. Visitors can expect lush landscapes and vibrant flora, making September a unique yet wet time to experience the natural beauty of Liberia.
In September, Liberia and Costa Rica experience a subtle shift in temperatures as the rainy season continues. The minimum temperature hovers around 21°C (69°F), providing warm nights, while the average temperature remains steady at 25°C (77°F), typical for this region. Days are pleasantly warm with a maximum temperature reaching 32°C (90°F). This trend reflects the gradual cooling as the year approaches its end, maintaining a comfortable climate ideal for exploration. Despite occasional rain showers, September invites visitors to indulge in the lush landscapes and vibrant culture, all while enjoying these mild temperatures.
In September, Liberia, Costa Rica experiences a significant uptick in rainfall, contributing 319 mm (12.6 inches) of precipitation over 25 days. This makes it one of the wettest months of the year, following closely behind the torrential rains of May and August. The consistent downpours signify the peak of the rainy season, as October edges even higher with an average of 418 mm (16.5 inches). As the rainy season progresses, the increasing frequency and volume of rainfall create a lush, vibrant landscape, highlighting the dynamic weather patterns that define this tropical paradise.
In September, Liberia, Costa Rica experiences a notable humidity level of 80%, contributing to the lush, tropical atmosphere characteristic of the region. This month follows a trend of increasing humidity that begins in late spring, peaking in July at a steamy 85%. As the dry season approaches, the humidity slightly decreases, dropping to 79% by October. Overall, the data reveals a subtropical climate where the humidity tends to remain high, especially during the rainy season, creating an environment that is both vibrant and invigorating. The consistent humidity levels throughout much of the year underscore Liberia's lush landscapes and diverse ecosystems, drawing nature lovers and adventurers alike to experience its natural beauty.
In September, Liberia, Costa Rica continues to experience an extreme UV Index of 13, requiring caution as just 10 minutes of sun exposure can lead to burns. Notably, this month maintains a high UV index similar to both August and October, indicative of a consistent trend throughout the year. From January to July, the UV Index peaked at 14, underscoring an intense sun exposure season, while only slightly lowering to 13 in late summer and early fall. As the year transitions into its final months, the UV Index begins to decrease, dropping to 11 in November and 10 in December. This pattern emphasizes the importance of sun safety year-round in Liberia – for more details on UV levels, visit Liberia UV Index.
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September in Liberia, Costa Rica, continues to bask in the region's abundant sunshine, recording 272 hours of bright light. This figure places it comfortably in the mid-range of the year’s sunshine statistics, following the peak months of March and April, which boast 334 and 326 hours, respectively. As the rainy season begins to mellow, September experiences a slight dip from the summer highs of July and August but remains vivid and inviting. This trend highlights a consistent pattern of sunny days that characterize the months leading into the lush green October, where the hours of sunshine begin to taper off. Whether you're soaking up the sun or enjoying the lush landscapes nourished by the seasonal rains, September offers a delightful blend of floral beauty and golden rays.
In Liberia, Costa Rica, the likelihood of sunny weather takes a notable dip in September, with only a 14% chance of sunshine. This month is one of the rainiest in the region, falling after the typically drier periods of January through April, which boast higher sun probabilities of over 50%. As the rainy season progresses, the chance for sunny skies diminishes significantly, peaking in August at a mere 8% before experiencing a slight uptick to 20% in October. Travelers looking for clear skies might want to plan their visits for the earlier months of the year when the weather is more favorable, while September is best suited for those who appreciate the lush, vibrant landscape that the rains can bring.
In September, Liberia, Costa Rica, enjoys a consistent 12 hours of daylight, a pattern that marks the peak of the wet season. Following the transitional months of April through August, where daylight duration remains steady at 12 hours, September maintains this vibrant schedule, allowing for plenty of time to explore the lush landscapes and rich biodiversity. As daylight begins to dwindle in October, dropping back to 11 hours, September stands out as a month where the abundance of light complements the region's enchanting atmosphere, making it an ideal time for adventurers and nature lovers alike to experience the beauty of this tropical paradise.
The September wind in Liberia, Costa Rica, typically whispers with an average speed of just 1.4 m/s (3 mph), making it one of the calmest months of the year. This gentle breeze follows a noticeable decline from the breezier early months, where speeds frequently reach double digits. After the lively gusts of March, which peak at 4.4 m/s (10 mph), the winds gradually lose their strength, especially as the rainy season deepens. By September, both the wind and atmosphere feel particularly tranquil, emphasizing the serene beauty of this lush region during the transitional period towards the drier months ahead. As October approaches, the winds remain mild, highlighting Liberia's inviting climate during this quiet time of year.
Weather in Liberia varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Liberia, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January showcase contrasting weather patterns. In September, temperatures range from a minimum of 21°C (69°F) to a maximum of 32°C (90°F), with an average of 25°C (77°F). This month is marked by high humidity at 80% and significant rainfall, totaling 319 mm (12.6 in) over 25 days. In stark contrast, January features slightly cooler temperatures, with a minimum of 16°C (60°F) and a maximum of 33°C (91°F), while maintaining the same average of 25°C (77°F). Moreover, January is considerably drier, receiving just 9 mm (0.4 in) of rainfall over only 2 days and a lower humidity level of 66%. For more information, you can visit Liberia weather in January.
September and February present distinctly different weather patterns. In September, temperatures typically range from a minimum of 21°C (69°F) to a maximum of 32°C (90°F), with an average temperature of 25°C (77°F). However, this month is characterized by significant rainfall, averaging 319 mm (12.6 inches) over 25 days, resulting in a high humidity level of 80%. In contrast, February enjoys milder weather, with temperatures ranging from a minimum of 18°C (64°F) to a maximum of 34°C (93°F) and an average temperature of 26°C (78°F). This month boasts very little precipitation, only 2 mm (0.1 inches), and has zero rainy days, contributing to a lower humidity level of 64%. For more detailed insights, check Liberia weather in February.
September and March present contrasting weather patterns. In September, average temperatures range from a minimum of 21°C (69°F) to a maximum of 32°C (90°F), marked by high humidity at 80% and significant rainfall, totaling 319 mm (12.6 in) over 25 days. In stark contrast, March enjoys slightly warmer average temperatures, with a minimum of 19°C (67°F) and a maximum of 35°C (95°F), accompanied by a remarkably dry spell, recording just 2 mm (0.1 in) of precipitation across 0 days and lower humidity at 63%. For more detailed weather insights, you can check Liberia weather in March.
September and April offer contrasting weather experiences. In September, temperatures range from a minimum of 21°C (69°F) to a maximum of 32°C (90°F), with an average of 25°C (77°F). This month is characterized by significant rainfall, totaling 319 mm (12.6 in) over 25 days, along with high humidity levels of 80%. In contrast, April features warmer temperatures, with a minimum of 20°C (68°F) and a maximum reaching up to 37°C (98°F), averaging 27°C (81°F). Rain is sparse in April, accumulating only 37 mm (1.4 in) over 6 days, and the humidity is noticeably lower at 63%. To learn more about Liberia's weather in April, visit Liberia weather in April.
When comparing the weather of September and May, you'll find some interesting contrasts. Both months experience similar minimum temperatures, with September at a minimum of 21°C (69°F) and May also at 21°C (69°F). However, May typically boasts a slightly higher average temperature of 26°C (80°F) compared to September’s average of 25°C (77°F). The maximum temperature in May can reach as high as 36°C (97°F), making it significantly warmer than September’s peak of 32°C (90°F).
Precipitation levels are also comparable, with September receiving 319 mm (12.6 in) over 25 days and May slightly higher at 323 mm (12.7 in) across 20 days. Additionally, September’s humidity is markedly higher at 80%, whereas May experiences a more comfortable 63% humidity. For more details about the weather in May, you can check out this Liberia weather in May.
In comparing the weather of September and June, both months feature similar temperature ranges, with September having a minimum of 21°C (69°F), an average of 25°C (77°F), and a maximum of 32°C (90°F). June shows slightly higher averages with a minimum of 21°C (70°F), an average of 26°C (78°F), and a maximum of 33°C (92°F). Precipitation levels are also comparable, with September receiving 319 mm (12.6 in) over 25 days, while June has just a bit less at 315 mm (12.4 in) over the same number of days. However, September experiences higher humidity at 80%, compared to June’s more comfortable 74%. For more detailed information, you can check Liberia weather in June.
When comparing the weather in September and July, both months have similar minimum and maximum temperatures, with September averaging 25°C (77°F) and July slightly warmer at 26°C (78°F). However, September experiences significantly higher precipitation, with 319 mm (12.6 in) over 25 days, contrasting sharply with July's 114 mm (4.5 in) over just 16 days. Additionally, humidity levels are slightly lower in September at 80%, compared to July's 85%. For more detailed information about conditions in July, you can check Liberia weather in July.
In comparing the weather of September to August, we find that both months experience warm conditions, with average temperatures hovering around 25°C (77°F). However, September tends to be slightly wetter, receiving 319 mm (12.6 in) of precipitation over 25 days compared to August's 250 mm (9.8 in) across 21 days. Additionally, while August has a maximum temperature of 33°C (92°F), September peaks at a slightly lower maximum of 32°C (90°F). Humidity levels are comparable, with August at 82% and September at 80%. For a more detailed look at weather patterns, you can visit Liberia weather in August.
September and October present a transitional period in weather, with both months sharing similar average temperatures, hovering around 25°C (77°F). However, October experiences slightly cooler minimum temperatures at 20°C (69°F) and a marginally lower maximum of 31°C (89°F) compared to September's minimum of 21°C (69°F) and maximum of 32°C (90°F). Rainfall becomes more pronounced in October, with precipitation rising to 418 mm (16.5 in) over 27 days, exceeding September's 319 mm (12.6 in) and 25 rainy days. The humidity remains consistent, at around 79% in October and 80% in September. For more details, you can explore Liberia weather in October.
In September, the weather is distinctly warmer and wetter compared to November, with temperatures ranging from a minimum of 21°C (69°F) to a maximum of 32°C (90°F). This month sees an average precipitation of 319 mm (12.6 in) over 25 days, contributing to heightened humidity levels of around 80%. In contrast, November experiences slightly cooler temperatures, with a minimum of 19°C (66°F) and a peak of 31°C (89°F), alongside significantly reduced rainfall of 153 mm (6.0 in) over just 12 days. The humidity remains similar at 79%, creating a comfortable atmosphere as the rainy season begins to wane. For more details, check out Liberia weather in November.
In September, the weather is characterized by warmer temperatures, with an average of 25°C (77°F) and peaks reaching up to 32°C (90°F). However, it is also the wettest month, experiencing significant precipitation of 319 mm (12.6 in) over 25 days, leading to high humidity levels around 80%. In contrast, December offers a slightly cooler climate, with similar average temperatures, but maximums only reaching 31°C (88°F). Significantly drier, December has just 17 mm (0.7 in) of rainfall over only 2 days, resulting in lower humidity at 70%. For those interested in more details about December’s climate, you can check this link: Liberia weather in December.
As September unfolds in Liberia, the weather presents a unique blend of warmth and moisture that sets it apart from other months. With temperatures consistently hovering around a pleasant average, the heat is often tempered by high humidity, creating a tropical atmosphere. The month experiences significant rainfall, making it one of the wettest periods of the year, with frequent showers impacting daily activities. This seasonal shift enhances the lush landscapes, bringing forth vibrant greenery and a refreshing ambiance. For those interested in understanding the broader context of this climatological pattern, further details can be found at Liberia Climate.