Last updated: August 21, 2025
September in Cariari, Costa Rica offers a tropical experience characterized by warm temperatures and abundant rainfall. With maximum temperatures reaching 31°C (89°F) and a comfortable average of 24°C (76°F), visitors can expect a blend of heat and humidity. However, minimum temperatures can drop to 19°C (66°F), providing some respite from the daytime warmth. The month is notably wet, accumulating nearly 192 mm (7.6 in) of rain over 27 days, contributing to the lush landscapes that make this region so vibrant. Humidity levels average around 84%, enhancing the tropical feel and reminding travelers of the rich biodiversity found in this beautiful area.
September in Cariari, Costa Rica showcases a harmonious blend of warm temperatures and lush tropical conditions. As the gateway to the rainy season, the month features a minimum temperature of 19°C (66°F), providing a comfortable start to the day, while afternoons see highs of around 31°C (89°F), maintaining a warm and inviting atmosphere. The average temperature hovers around 24°C (76°F), reflecting a consistent warmth that is characteristic of this vibrant locale. Despite the slightly increased humidity due to the rains, the temperatures remain relatively stable throughout the month, aligning closely with those of the preceding summer months. Visitors can expect a delightful mix of sunshine and refreshing afternoon showers, making September an ideal time for experiencing the lush beauty of Cariari.
In September, Cariari, Costa Rica experiences a noteworthy transition in its precipitation pattern, receiving 192 mm (7.6 in) of rainfall over 27 days. This month sits slightly below the deluge of previous months, such as May's dramatic 356 mm, yet it is still a significant contributor to the region's overall wetness as it approaches the peak of the rainy season. Following a trend seen in the late summer, precipitation in September remains consistent, with nearly seven out of eight days marked by rainfall, fostering the lush, vibrant landscapes that define this tropical paradise. As the landscape continues to thrive under these humid conditions, the stage is set for even heavier downpours in October, which typically sees a substantial uptick to 405 mm.
September in Cariari, Costa Rica, showcases a notable peak in humidity, averaging 84%, as the region transitions further into the rainy season. This month follows the high readings of August and July, which hover around 85% and 88%, respectively, indicating a trend of increasing moisture in the air during these late summer months. While the humidity remains elevated compared to the drier months of winter—like January and February, both around 70%—September's climate serves as a reminder of the lush, vibrant environment that defines Costa Rica. The gradual increase from late spring through the summer suggests a rich tapestry of ecology, with the rising humidity playing a crucial role in sustaining the diverse flora and fauna characteristic of the region.
In September, Cariari, Costa Rica, maintains a consistently high UV Index of 13, reflecting the extreme sun exposure typical of the region. This marks a continuation of a trend observed throughout the year, where the UV Index remains alarmingly high, particularly from January to May, peaking at 14 in the spring months. Although the index slightly dips in the latter part of the year, including October, the burn time remains notably short at just 10 minutes throughout this period. The unwavering ultraviolet radiation underscores the importance of sun protection for both residents and visitors. For more detailed information about UV levels, check out the Cariari UV Index.
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In September, sunshine graces Cariari, Costa Rica with an impressive 275 hours of radiant daylight, making it a delightful time to visit. This month maintains a commendable brightness following the more pronounced sunshine of the prior months, particularly March with its peak of 326 hours. As the rainy season begins to wane, September's hours strike a harmonious balance between light and the refreshing showers typical of the region, providing a unique opportunity to bask in the tropical sunshine while enjoying the lush vibrancy of nature. Notably, as we transition into October, the sunshine remains strong, ensuring that this lush paradise continues to captivate with its consistent warmth and abundant beauty.
In Cariari, Costa Rica, the likelihood of sunny weather experiences a notable decline from the early part of the year into September, where the chances of sunshine drop to 15%. As the dry season wanes from January through March, sun enthusiasts can enjoy a stable 43-46% chance of clear skies. However, as the rainy season kicks in, the optimism for sunny days diminishes significantly, with April and May seeing a steep decline to just 21% and 17%, respectively. This trend continues into the heart of the rainy season, reaching an all-time low of 10% in August. While September revives the possibility slightly to 15%, it remains one of the least favorable months for sun seekers, foreshadowing the gradual increase in sunshine as the year approaches its end.
In September, Cariari, Costa Rica enjoys an ample 12 hours of daylight, a continuation of the consistent daylight hours seen since March. This trend of extended daylight is part of the region's distinct pattern, where the daylight duration remains stable at 12 hours from March through August. As the year progresses into October, daylight begins to shorten again, reverting to 11 hours, along with the encroaching rainy season. This consistent rhythm of light and shadow not only shapes daily life in Cariari but also highlights the area’s tropical climate, offering a vibrant backdrop for both residents and visitors alike.
In September, the tranquil winds of Cariari, Costa Rica reach a gentle whisper, averaging only 1.1 m/s (2 mph). This calmness is part of a broader trend as the wind speeds tend to decline during the wet season, creating a serene atmosphere that invites relaxation. After peaks in the early months of the year, where gusts reached up to 1.7 m/s (4 mph) in March, the summer months illustrate a consistent decrease, culminating in September's gentle breezes. This subtle shift is particularly welcome amidst the region's lush, vibrant landscape, enhancing the sense of peaceful enjoyment in this tropical paradise. As the year transitions into October, the winds remain mild, continuing the trend of tranquility that September encapsulates.
Weather in Cariari varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Cariari, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January offer distinct weather experiences, reflecting the transition from late summer to the heart of winter. In September, temperatures range from a minimum of 19°C (66°F) to a maximum of 31°C (89°F), averaging around 24°C (76°F). The month is characterized by high humidity at 84% and considerable rainfall, with 192 mm (7.6 in) over 27 days. In contrast, January features slightly cooler temperatures, with minimums of 16°C (62°F) and maximums of 28°C (82°F), averaging 22°C (72°F). Although January sees a bit more precipitation at 203 mm (8.0 in), it is spread over just 14 days, resulting in lower humidity of 71%. For more details on January weather, you can visit Cariari weather in January.
September and February showcase distinct weather characteristics. In September, temperatures range from a minimum of 19°C (66°F) to a maximum of 31°C (89°F), with an average temperature of 24°C (76°F). This month is marked by significant rainfall, totaling 192 mm (7.6 in) over 27 days, accompanied by high humidity levels at 84%. In contrast, February experiences milder conditions, with temperatures varying from a minimum of 15°C (60°F) to a maximum of 30°C (86°F), leading to an average of 22°C (72°F). Precipitation during this month is notably lower at 86 mm (3.4 in), occurring over 13 days, and humidity levels decrease to 70%. For more insights into the February climate, visit Cariari weather in February.
September and March showcase distinct weather patterns, revealing the transition from late summer to early spring. In September, temperatures range from a minimum of 19°C (66°F) to a maximum of 31°C (89°F), with an average of 24°C (76°F). This month also sees significant precipitation, totaling 192 mm (7.6 in) over 27 days, along with high humidity at 84%. In contrast, March experiences slightly cooler temperatures with a minimum of 16°C (62°F) and a maximum of 30°C (86°F), averaging 23°C (73°F). Rainfall is considerably less in March, totaling 93 mm (3.7 in) over 15 days and with lower humidity at 68%. For a more detailed look at weather conditions in this month, visit Cariari weather in March.
In a comparison of September and April weather, both months exhibit similar average temperatures, maintaining an average of around 24°C (75°F). However, September is characterized by higher humidity at 84%, compared to April's more comfortable 69%. Additionally, September sees significantly more precipitation, with 192 mm (7.6 in) over 27 days, while April has only 120 mm (4.7 in) across 23 days. For more detailed insights on April weather, you can check Cariari weather in April.
In comparing the weather of September and May, both months showcase a similar range of temperatures, with minimums around 19°C (66°F) and average highs of approximately 24°C (76°F). However, May tends to be slightly warmer, peaking at 32°C (91°F), while September reaches a maximum of 31°C (89°F). Precipitation levels indicate a significant difference; May experiences higher rainfall, totaling 356 mm (14.0 in) over 28 days, compared to September’s 192 mm (7.6 in) spread across 27 days. Humidity is also slightly more pronounced in September, at 84%, while May maintains a lower humidity level of 70%. For more detailed weather insights, you can explore Cariari weather in May.
When comparing the weather in September and June, both months feature similar average temperatures, ranging from a minimum of 19°C (66°F) to a maximum of 32°C (89°F). However, June tends to be slightly warmer with an average low of 20°C (68°F). In terms of precipitation, June is wetter, receiving 269 mm (10.6 in) over 28 days, while September sees 192 mm (7.6 in) with rainfall on 27 days. Humidity levels are relatively high in both months, with September at 84% and June slightly lower at 81%. For more specific insights about weather in June, you can check Cariari weather in June.
When comparing the weather in September and July, we can see some interesting similarities and differences. Both months have a minimum temperature of around 19°C (66°F), average temperatures hovering around 24°C (75-76°F), and a maximum temperature reaching 31°C (87-89°F). However, September experiences slightly less precipitation at 192 mm (7.6 in) over 27 days, compared to July's 286 mm (11.3 in) over 28 days. Additionally, September's humidity is slightly lower at 84% versus July's 88%, making September feel a touch drier. For more detailed information on July weather, you can check Cariari weather in July.
In comparing the weather between September and August, both months exhibit similar temperatures, with September having a slightly lower minimum temperature of 19°C (66°F) compared to 20°C (68°F) in August. The average temperature remains the same at 24°C (76°F), while August reaches a maximum of 32°C (89°F), just one degree higher than September's maximum of 31°C (89°F). Rainfall is more frequent in September, with 192 mm (7.6 in) over 27 days, whereas August sees 203 mm (8.0 in) across 28 days. Humidity levels are also quite comparable, with September at 84% and August slightly higher at 85%. For more insights into August's conditions, you can refer to Cariari weather in August.
In comparing the weather between September and October, both months feature similar temperature ranges, with minimum temperatures hovering around 19°C (66°F), average temperatures approximately 24°C (75-76°F), and maximums reaching up to 31°C (89°F). However, October experiences significantly more precipitation, measuring 405 mm (15.9 in) over 29 days, compared to September's 192 mm (7.6 in) across 27 days. Additionally, humidity levels remain relatively high, averaging 82% in October, slightly lower than September's 84%. This increase in rainfall may suggest more overcast days in October, making it crucial to stay informed about the weather conditions. For more detailed insights, you can check Cariari weather in October.
In comparison to September, November experiences slightly lower average temperatures, with a minimum of 19°C (66°F) and a maximum of 30°C (86°F), down from September's highs of 31°C (89°F). Both months showcase high humidity levels, though November is marginally drier, with humidity at 81% compared to 84% in September. However, November is significantly wetter, receiving 334 mm (13.1 in) of rainfall over 26 days, compared to September's 192 mm (7.6 in) over 27 days. For more detailed insights into November's weather, check Cariari weather in November.
In September, the weather is typically warm with a minimum temperature of 19°C (66°F) and an average of 24°C (76°F), peaking at a maximum of 31°C (89°F). However, this month experiences significant rainfall, averaging 192 mm (7.6 in) over 27 days, along with high humidity levels at 84%.
Comparatively, December sees slightly cooler temperatures, with a minimum of 17°C (64°F) and an average of 23°C (73°F), reaching a maximum of 29°C (84°F). While it still experiences considerable rainfall, totaling 320 mm (12.6 in) over 20 days, the humidity is lower at 74%. For more detailed information, you can check Cariari weather in December.
As September rolls in, Cariari experiences a notable shift in weather patterns that sets it apart from the drier months. With high humidity levels hovering around 84% and an average temperature of 24°C (76°F), the air feels cooler yet consistently moist. This month is characterized by frequent rainfall, accumulating a substantial 192 mm (7.6 in) over 27 days, making it one of the wettest periods of the year. While the warmth remains with maximum temperatures reaching up to 31°C (89°F), the increased precipitation creates a lush, vibrant environment that invites outdoor exploration. Be sure to check out the detailed insights on the climate throughout the year at Cariari Climate.