Last updated: August 21, 2025
In September, Cartago, Costa Rica experiences a temperate climate characterized by a maximum temperature of 25°C (77°F) and a cool average of 18°C (65°F). With minimum temperatures dipping to 14°C (57°F), the weather is generally mild and refreshing. However, this month is also marked by substantial rainfall, recording a significant 508 mm (20.0 in) of precipitation across 30 days. The humidity remains high at 81%, contributing to the lush greenery that defines this beautiful region. Overall, September in Cartago offers a unique blend of refreshing temperatures and vibrant, rain-soaked landscapes.
In September, Cartago, Costa Rica enjoys a mild and stable climate, characterized by a comfortable range of temperatures. With a minimum of 14°C (57°F) and a maximum of 25°C (77°F), the month harmoniously balances warm days and cool evenings, maintaining an average of 18°C (65°F). This consistency is a trend throughout the year, as temperatures remain relatively moderate, only varying slightly as the months change. While September may coincide with the rainy season, the mild temperatures make it an appealing time for visitors to explore the lush landscapes and vibrant culture of this beautiful region. So, whether you’re wandering through local markets or enjoying the scenic views, expect pleasant weather that invites exploration.
In September, Cartago, Costa Rica, experiences a significant surge in precipitation, with an impressive 508 mm (20.0 in) of rainfall over 30 days. This marks one of the wettest months of the year, following the trend established in the preceding months of the rainy season. The rainfall in September, while substantial, is slightly less than the peak seen in October, which typically receives the most precipitation. This month’s consistent downpours contribute to the lush, vibrant landscapes that characterize the region, offering a refreshing contrast to the dry months earlier in the year. As the rainfall taps persistently throughout September, it not only nourishes the local flora but also sets the stage for the dramatic and picturesque scenery that Cartago is known for during the wet season.
In September, Cartago, Costa Rica, experiences a notable rise in humidity, reaching 81%. This peak follows the trend of increased moisture during the rainy season, which begins around June and continues through the fall. Notably, the humidity levels climb significantly from a steady average of 68% to 69% in the earlier months of the year, spiking to 84% in June and maintaining elevated levels throughout the summer. While September's humidity is slightly lower than the 85% recorded in July, it retains the signature mugginess of the month, contributing to the lush, vibrant landscapes that characterize this region during the rainy season. As the year transitions into October, humidity gradually decreases, settling back to 80%, indicating a slow shift towards drier conditions.
In September, Cartago, Costa Rica, continues to experience a notably high UV Index of 14, categorizing the exposure as extreme. This month mirrors the UV levels of both August and October, where residents and visitors alike should remain vigilant, as the consistent burn time is a mere 10 minutes. This trend reflects the dry season's impact on UV radiation, with the levels peaking in the earlier months like March and April. As you enjoy the beautiful surroundings, remember to take proactive sun protection measures to minimize the risk of sunburn. For more detailed information on daily variations, check out the Cartago UV Index.
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September in Cartago, Costa Rica, brings a gentle transition as sunshine gently wanes, offering 219 hours of delightful daylight. While this count is slightly lower than the summer months, it follows a consistent trend of decreasing sunlight from the peak of 331 hours in March down to October's 206 hours. The lush rains of September infuse the landscape with vibrant greenery, making it a beautiful time to experience the region’s natural beauty. As the year progresses towards the drier months, the gradual reduction in sunlight serves as a reminder of the cyclical rhythms of tropical life, where each month unfolds its own unique charm.
In Cartago, Costa Rica, the likelihood of enjoying sunny weather takes a notable dip in September, with only an 8% chance of sunshine. This trend highlights the transition into the rainy season, where cloud cover and precipitation become increasingly prevalent. As we journey through the year, September emerges as one of the cloudiest months, contrasting sharply with the sun-kissed days typical of earlier months like January, which boasts a 54% chance of sun. The shift in weather patterns throughout the year paints a vivid picture of Cartago's climate, revealing the region's striking seasonal diversity.
As the seasons change in Cartago, Costa Rica, September marks a delightful continuation of consistent daylight duration, offering 12 hours of sunlight each day. This aligns seamlessly with the months of March through August, showcasing a remarkable stability in daylight that enhances the region's vibrant atmosphere. Following this peak, daylight gradually begins to taper off in October, returning to 11 hours as the year approaches its end. Overall, September embodies the essence of tropical equilibrium, allowing for leisurely exploration and enjoyment of nature both day and night.
In September, the breezy climate of Cartago, Costa Rica experiences an average wind speed of 1.2 m/s (3 mph), blending tranquility with a gentle touch of movement in the air. As the month progresses, the wind speeds reflect a subtle decline from the drier months earlier in the year, but still manage to maintain a soothing atmosphere for both locals and visitors alike. This slight dip follows the trend observed since the mid-year mark, with average speeds hitting their lowest in the rainy months of June and August. As October approaches, the winds are likely to linger around similar speeds, inviting a peaceful end to the season. Overall, September's breeze, while modest, plays a harmonious role in the changing landscape of Cartago, capturing the essence of the season with its soft and refreshing presence.
Weather in Cartago varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Cartago, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present distinct weather patterns, with September being noticeably wetter and more humid. In September, temperatures range from a minimum of 14°C (57°F) to a maximum of 25°C (77°F), accompanied by a high average temperature of 18°C (65°F) and significant rainfall of 508 mm (20.0 in) over 30 days, resulting in a humidity level of 81%. Conversely, January experiences slightly cooler temperatures with a minimum of 11°C (51°F) and a maximum of 24°C (76°F), averaging 17°C (63°F). This month enjoys much lower precipitation, totaling just 35 mm (1.4 in) over 6 days and a lower humidity of 68%. For more details, visit Cartago weather in January.
When comparing the weather in September and February, notable differences emerge. September experiences a wider range of temperatures, with a minimum of 14°C (57°F) and a maximum of 25°C (77°F), while February sees slightly cooler minimums at 11°C (51°F) but shares a similar maximum of 25°C (76°F). September is characterized by significantly higher rainfall, with 508 mm (20.0 in) over 30 days, contributing to higher humidity levels at 81%. In contrast, February enjoys a much drier climate with only 19 mm (0.8 in) of precipitation across 5 days and lower humidity at 68%. For more detailed insights into February weather, you can check out Cartago weather in February.
In September, the weather is characterized by higher humidity and significant rainfall, with an average temperature of 18°C (65°F) but a notable 508 mm (20.0 in) of precipitation over 30 days. This contrasts sharply with March, which also averages 18°C (65°F) but experiences much less rain at only 28 mm (1.1 in) over just 6 days and lower humidity at 66%. Both months may reach a maximum of 25°C (77°F), but September's dampness and persistent rain create a much different atmosphere compared to the drier, more comfortable conditions of March. For more specifics on March weather, you can check Cartago weather in March.
September and April exhibit some similarities in temperature but differ significantly in precipitation and humidity. In both months, the average temperature hovers around 18°C (65°F), with April experiencing slightly warmer maximum temperatures of 26°C (78°F) compared to September's peak of 25°C (77°F). However, September is characterized by significantly higher precipitation, with 508 mm (20.0 in) falling over 30 days, while April sees only 155 mm (6.1 in) over 23 days. Additionally, September has higher humidity at 81%, compared to April’s more comfortable 67%. For a closer look at April's weather specifics, visit Cartago weather in April.
When comparing the weather in September and May, it's notable that both months share similar minimum and average temperatures, with September peaking at 25°C (77°F) and May slightly warmer at 26°C (79°F). However, September experiences a heavier rainfall of 508 mm (20.0 in) over 30 days, compared to May's 532 mm (21.0 in) over 29 days. Additionally, September has a higher humidity level of 81%, whereas May is less humid at 69%. For more specifics about May weather, you can check Cartago weather in May.
In comparing the weather of September and June, we observe some similarities and differences. Both months have a minimum temperature of 14°C (57°F) and an average temperature of 18°C (around 65-66°F), with maximum temperatures reaching 25°C (77°F) for September and 25°C (76°F) for June. However, September experiences significantly more precipitation, totaling 508 mm (20.0 in) over 30 days, compared to June's 399 mm (15.7 in) over 29 days. Additionally, humidity levels are slightly higher in June at 84% versus September's 81%. For a closer look at June's weather details, check out Cartago weather in June.
Comparing the weather in September and July, we can see some notable differences. Both months have similar minimum and average temperatures, with September having a slightly higher maximum temperature of 25°C (77°F) compared to July's 24°C (76°F). However, September experiences significantly more precipitation, with 508 mm (20.0 in) over 30 days, compared to July's 315 mm (12.4 in) over 28 days. This leads to slightly higher humidity levels in July at 85%, compared to 81% in September. For more specific insights into July weather, you can check Cartago weather in July.
In comparing the weather between September and August, we can see that both months have similar temperature ranges, with minimum temperatures at 14°C (57°F) and average highs around 25°C (77°F). However, September experiences a significant increase in precipitation, with 508 mm (20.0 in) of rainfall compared to August's 403 mm (15.9 in). Despite the slight drop in humidity, averaging 81% in September versus 82% in August, the overall atmospheric conditions remain quite similar. For more detailed information on August weather, you can visit Cartago weather in August.
September generally experiences mild temperatures with a minimum of 14°C (57°F) and a maximum of 25°C (77°F), averaging around 18°C (65°F). This month is characterized by significant rainfall, totaling 508 mm (20.0 in) across 30 days, and a high humidity level of 81%. In contrast, October sees slight shifts in the weather, with temperatures dipping to a minimum of 13°C (55°F) and a maximum of 24°C (76°F), while still averaging 18°C (64°F). Rainfall increases to 601 mm (23.7 in) over the same number of days, accompanied by a humidity level of 80%. For more details on October's conditions, you can visit Cartago weather in October.
September generally experiences slightly warmer temperatures compared to November, with an average of 18°C (65°F) and maximum highs reaching 25°C (77°F). In contrast, November maintains a similar average temperature of 18°C (64°F), but the maximum drops slightly to 24°C (75°F). While both months share comparable humidity levels around 80-81%, September sees significantly more precipitation, totaling 508 mm (20.0 in) over 30 days, compared to November's 272 mm (10.7 in) over 26 days. For more detailed information, you can check Cartago weather in November.
September and December exhibit distinct weather patterns. In September, temperatures range from a minimum of 14°C (57°F) to a maximum of 25°C (77°F), with an average of 18°C (65°F). This month is characterized by significant rainfall, totaling 508 mm (20.0 in) over 30 days, leading to high humidity levels of 81%. In contrast, December sees slightly cooler temperatures, with a minimum of 12°C (54°F) and a maximum of 24°C (75°F), averaging 17°C (64°F). Precipitation drops dramatically to 78 mm (3.1 in) over just 11 days, contributing to a lower humidity of 72%. For more details, you can visit Cartago weather in December.
As September unfolds in Cartago, the atmosphere transforms into a lush and vibrant landscape, characterized by high humidity and frequent rains. With nearly every day witnessing rainfall, this month stands in stark contrast to the drier periods that precede and follow it. The temperatures remain relatively mild, showcasing the typical embrace of tropical climates while also creating a refreshing ambiance that invites nature lovers to explore its verdant surroundings. For those curious about the intricacies of Cartago’s climate, this month is particularly unique, providing ample opportunity to experience the region’s dynamic weather patterns. To learn more about the climate throughout the year, visit Cartago Climate.