Last updated: August 21, 2025
In September, Santiago Atitlan, Guatemala experiences a mild and humid climate, with maximum temperatures reaching around 24°C (75°F) and an average temperature of 18°C (64°F). The nights can be cool, dipping to a minimum of 12°C (54°F). This month is characterized by significant rainfall, with a notable precipitation total of 358 mm (14.1 in) across approximately 26 days, leading to a humidity level of 82%. Travelers to this stunning lakeside town should be prepared for wet conditions, but the lush landscape and vibrant culture in the midst of these showers present a unique and captivating experience.
September in Santiago Atitlán, Guatemala brings a mild and pleasant climate, characteristic of the rainy season. With temperatures ranging from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), the weather remains comfortably cool, making outdoor explorations enjoyable. The average temperature hovers around 18°C (64°F), consistent with the trends seen in preceding months. While both June and July share similar averages, September’s slightly lower maximum indicates a gradual transition toward the cooler months ahead. This month provides a delightful balance for visitors and locals alike, allowing for vibrant experiences amidst the stunning natural beauty surrounding Lake Atitlán.
In September, Santiago Atitlán experiences a significant surge in precipitation, receiving an impressive 358 mm (14.1 in) over 26 days of rainfall. This marks a continuation of the wet season, which peaks in May but remains robust through early fall. The heightened rainfall in September contributes to the lush, verdant landscape typical of the region, as the ongoing precipitation patterns show a clear trend towards higher moisture levels compared to the preceding months. Following the pattern established in August, September's rainfall solidifies its position as a month where visitors can expect dramatic scenery, though they should also be prepared for the regular deluges that accompany this vibrant season.
In September, Santiago Atitlán experiences a notable peak in humidity, reaching 82%, which aligns with the pattern observed in the preceding months. Following a gradual increase throughout the summer, where humidity levels rise from 75% in July to 82% in August, September maintains this elevated moisture level, signifying a transition into the wetter season. This heightened humidity continues into October, achieving 83%, creating a lush and vibrant environment. As the year progresses towards the cooler months, humidity levels slightly decrease, but September effectively captures the essence of tropical rainy season, enveloping the region in a rich, humid embrace.
In Santiago Atitlan, Guatemala, September brings a UV Index of 14, categorizing sun exposure as extreme with a burn time of just 10 minutes. This high UV Index is consistent with the preceding months, where indices hovered around 14 to 16, indicating a persistent need for sun protection year-round. As the rainy season approaches, it’s crucial to remain vigilant, as even with cloud cover, UV rays can still be intensely damaging. Understanding these trends is essential for both locals and visitors to enjoy the stunning landscapes while staying safe. For more detailed information, check out the Santiago Atitlan UV Index.
UV Risk Categories
In September, Santiago Atitlán enjoys a delightful blend of warmth and sunshine, boasting 287 hours of glorious daylight. This month marks a gentle transition from the vibrant summer months, with sunlight hours gradually tapering down from the peak of 321 hours in March and the robust 314 hours experienced in July. As the rainy season draws to a close, September offers a comfortable reprieve, making it an inviting time for exploration and reflection amid stunning lake views and lush landscapes. The consistent presence of sunshine throughout the year, particularly in contrast to the cooler, cloudier months of January and June, showcases Santiago Atitlán as a year-round haven for sun seekers and nature lovers alike.
As September rolls into Santiago Atitlán, the promise of sunshine is considerably diminished, with only a 14% chance of clear skies. This marks a continuation of the trend from the preceding months, where the likelihood of sunny weather consistently declines, reaching a low in June and July. After August's modest increase, the sunshine chance remains static in September, reflecting the region's transition into the wetter season. However, as fall approaches in October, a subtle uptick to 30% hints at the possibility of more favorable weather conditions in the coming months. Overall, while September may not be ideal for sun-seekers, it sets the stage for the changing climate of the autumn season.
In September, Santiago Atitlan enjoys a consistent daylight duration of 12 hours, mirroring the trend established in the preceding months. As the region transitions from the vibrant summer months into autumn, the length of daylight levels off, offering ample time for both exploration and relaxation under the tropical sun. This stable daylight period, beginning in March and extending through September, creates an ideal backdrop for outdoor activities and cultural experiences. As October approaches, the daylight gradually begins to recede, returning to the shorter 11-hour days typical of the latter months of the year.
As September unfolds in Santiago Atitlan, Guatemala, a gentle, cool breeze graces the landscape, with average wind speeds dipping to 1.3 m/s (3 mph). This marks a continuation of the trend observed through the summer months, where winds have gradually slowed from the slightly brisker breezes of earlier in the year. After a peak in wind speed during the winter months, the late summer transition brings a serene calm, allowing for a tranquil atmosphere that beautifully complements the vibrant scenery. As the year progresses toward October, the consistent wind patterns suggest a gentle shift into the quieter, cooler months, enhancing the allure of this picturesque lakeside town.
Weather in Santiago Atitlan varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Santiago Atitlan, focusing on differences in temperature, rainfall, humidity, and UV levels.
When comparing the weather in September and January, one can observe notable differences in both temperature and precipitation. September typically experiences a milder range of temperatures, with averages around 18°C (64°F) and maximums reaching up to 24°C (75°F). However, it is characterized by significantly higher precipitation, averaging 358 mm (14.1 in) over 26 days, contributing to a humid environment with 82% humidity.
In contrast, January features cooler temperatures with a minimum of 8°C (47°F) and an average of 16°C (61°F), while still reaching a similar maximum of 24°C (76°F). The precipitation in January is drastically lower, averaging only 16 mm (0.6 in) over just 5 days, and the humidity is slightly reduced at 76%. For a deeper look into the weather nuances during this month, check out Santiago Atitlan weather in January.
September and February offer contrasting weather experiences. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), with an average of 18°C (64°F). This month is characterized by high precipitation, receiving 358 mm (14.1 in) spread over 26 days and a humidity level of 82%. In contrast, February boasts slightly cooler temperatures, with a minimum of 10°C (50°F) and a maximum of 26°C (79°F), averaging 17°C (62°F). The weather in February is much drier, with only 34 mm (1.3 in) of rain over 8 days and a humidity of 68%. For more details on the February weather, you can explore Santiago Atitlan weather in February.
In September, the weather is generally cooler and wetter compared to March. With average temperatures ranging from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), September experiences significantly higher humidity at 82% and substantial rainfall totaling 358 mm (14.1 in) over 26 days. In contrast, March features milder conditions, with temperatures ranging from a minimum of 9°C (49°F) to a maximum of 27°C (80°F), and a much lower precipitation level of 53 mm (2.1 in) spread over just 8 days, resulting in a 59% humidity level. For more detailed information on weather patterns, you can visit Santiago Atitlan weather in March.
When comparing the weather in September and April, both months exhibit similar average temperatures of around 18°C (64°F). However, September tends to be cooler at night with a minimum temperature of 12°C (54°F) compared to April’s slightly cooler minimum of 10°C (50°F). In terms of daytime highs, September reaches a maximum of 24°C (75°F), while April can get warmer, peaking at 26°C (79°F). Precipitation is significantly higher in September, with 358 mm (14.1 in) over 26 days, contrasting sharply with April's 159 mm (6.2 in) spread across only 19 days. Additionally, September's humidity is notably higher at 82%, compared to April's 57%. For more detailed information, you can check out Santiago Atitlan weather in April.
When comparing the weather in September and May, it is clear that both months share a similar temperature range, with September having a minimum of 12°C (54°F) and an average of 18°C (64°F), while May sees a slight increase in the maximum temperature, peaking at 26°C (78°F). However, May experiences significantly more precipitation, totaling 449 mm (17.7 in) over 29 days, compared to September's 358 mm (14.1 in) across 26 days. Additionally, September’s humidity level is notably higher at 82%, while May's humidity is more moderate at 65%. For a detailed look at what to expect in the month of May, you can check Santiago Atitlan weather in May.
When comparing the weather in September and June, we find that both months feature similar average temperatures, with September ranging from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), and June seeing slightly warmer minimums at 13°C (56°F) while still reaching a maximum of 24°C (76°F). However, September experiences significantly higher precipitation, with 358 mm (14.1 in) falling over 26 days, compared to June’s 405 mm (15.9 in) over 27 days. Additionally, humidity levels are notably higher in September at 82%, while June boasts a more comfortable 66% humidity. For more detailed insights, you can check Santiago Atitlan weather in June.
When comparing the weather in September to that of July, we observe some notable differences. September features slightly cooler temperatures, with a minimum of 12°C (54°F) and a maximum of 24°C (75°F), while July sees temperatures ranging from 13°C (55°F) to a maximum of 25°C (76°F). Additionally, September experiences significantly more precipitation, totaling 358 mm (14.1 in) over 26 days, compared to July's 157 mm (6.2 in) over just 16 days. The humidity also increases in September, averaging around 82%, compared to 75% in July. For a more detailed look at July's weather, you can check out Santiago Atitlan weather in July.
In September, temperatures remain consistent with those of August, both recording a minimum of 12°C (54°F) and an average of 18°C (64°F). However, September experiences slightly cooler maximum temperatures, peaking at 24°C (75°F) compared to August's higher maximum of 26°C (78°F). Additionally, September is notably wetter, with 358 mm (14.1 in) of precipitation falling over 26 days, while August sees 290 mm (11.4 in) of rain over 24 days. Humidity levels remain constant at 82% for both months. For more detailed insights about August weather, you can visit Santiago Atitlan weather in August.
In September, temperatures in Santiago Atitlan range from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), with an average of 18°C (64°F). The month is marked by significant rainfall, totaling 358 mm (14.1 in) over 26 days, resulting in a high humidity level of 82%.
In contrast, October experiences slightly cooler conditions with an average temperature of 17°C (64°F), while still reaching a maximum of 24°C (76°F). Precipitation decreases to 292 mm (11.5 in) over 27 days, and humidity rises marginally to 83%. Overall, while both months share similar temperature ranges, October tends to be a bit wetter and cooler compared to September. For more details on weather specifics, check out Santiago Atitlan weather in October.
In comparing the weather of September and November, both months exhibit similar maximum temperatures, reaching up to 24°C (75°F). However, September tends to be warmer overall, with an average temperature of 18°C (64°F) compared to November's 17°C (63°F). Precipitation also differs significantly; September experiences a high of 358 mm (14.1 in) over 26 days, while November sees substantially less rain at 64 mm (2.5 in) across just 10 days. Humidity levels are slightly lower in November at 80%, compared to September's 82%, contributing to a somewhat drier atmosphere. For a more detailed look at November weather in Santiago Atitlan, you can check Santiago Atitlan weather in November.
September and December exhibit distinct differences in weather patterns. In September, temperatures range from a minimum of 12°C (54°F) to a maximum of 24°C (75°F), with an average of 18°C (64°F). This month is marked by significant rainfall, totaling 358 mm (14.1 in) over 26 days, leading to high humidity levels of 82%. In contrast, December presents a cooler climate with temperatures ranging from a low of 8°C (47°F) to a high of 24°C (75°F), averaging at 16°C (62°F). Precipitation dramatically decreases to just 22 mm (0.9 in) over only 5 days, resulting in lower humidity at 76%. For a more detailed look at December weather, you can check out Santiago Atitlan weather in December.
As September rolls into Santiago Atitlan, the weather takes on a distinctive character marked by increased rainfall and humidity. With an average temperature of 18°C, this month is cooler compared to the warmer summer months, making it an inviting time for those who prefer a milder climate. However, be prepared for the higher precipitation, as September typically sees 26 days of rainfall, casting a lush green hue over the landscape. The substantial humidity at 82% adds to the tropical ambiance, creating a unique experience that stands in stark contrast to drier months. For more insights on what to expect, check out the detailed information here: Santiago Atitlan Climate.