Last updated: August 28, 2025
September weather in Co To, Vietnam is characterized by warm temperatures and substantial rainfall. With a maximum of 31°C (88°F) and an average of 28°C (83°F), the warmth is complemented by a minimum of 25°C (77°F), creating a humid atmosphere with 78% humidity. Expect a significant amount of precipitation, with around 360 mm (14.2 in) falling over approximately 22 days. This combination of heat and humidity makes September a vibrant yet challenging month for visitors looking to explore the island's natural beauty.
In September, temperatures in Co To, Vietnam begin to transition into the cooler months, but still hold onto the summer warmth. With minimum temperatures hovering around 25°C (77°F), the average reaches a pleasant 28°C (83°F), and the maximum can go up to 31°C (88°F). This gradual decrease from the peak summer heat of previous months marks the onset of the fall season, yet it maintains a comfortable atmosphere for outdoor activities. Visitors can relish the warm days while enjoying refreshing sea breezes, making September an enticing time to explore this beautiful coastal paradise.
In September, Co To, Vietnam experiences a significant transition in its rainy season, marked by a substantial precipitation amount of 360 mm (14.2 in) over approximately 22 days of rainfall. This downpour follows the peak rainfall months of July and August, which see extremes of 435 mm (17.1 in) and 594 mm (23.4 in), respectively. The rainfall in September continues to contribute to the area's lush, vibrant landscape while also indicating a gradual decline in precipitation as the year progresses into October, when totals drop to 273 mm (10.8 in). This trend highlights a rhythmic pattern in Co To's climate, where the summer months are characterized by intense rainfall, providing a contrast to the drier months that follow.
In September, Co To, Vietnam, experiences a slight dip in humidity, averaging 78%. While this is an improvement from the peak humidity months of July and August, both registering at an impressive 86%, it maintains a noticeably higher level compared to earlier months. Following the trend from May through August, when humidity levels escalated steadily, September marks a transition as the monsoon season begins to wane. The return to lower humidity in October at 72% suggests a gradual shift towards drier conditions as the year progresses, offering a brief respite before the humidity levels rise again in the following months. Overall, September serves as a pivotal point in Co To’s climate, bridging the steamy summer days with the cooler, less humid autumn.
In September, Co To, Vietnam experiences a UV Index of 13, categorized as extreme, with a burn time of just 10 minutes. This trend of high UV exposure continues from the peak summer months of July and August, where the UV Index reached a maximum of 14. The consistency of extreme UV levels from April through September highlights the importance of sun protection during this period. Travelers and locals alike should remain vigilant, as even brief exposure can lead to sunburn. As the year progresses towards October, there is a slight dip in the index to 11, yet the warning remains: don't underestimate the sun's power in this beautiful coastal paradise. For more detailed information on UV levels throughout the year, visit Co To UV Index.
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September in Co To, Vietnam, brings a delightful abundance of sunshine, with 291 hours of bright daylight illuminating the island. This charming month continues the upward trend established in the previous summer months, showcasing increased sunshine compared to the earlier parts of the year. As the summer peak of 314 hours in May and 306 hours in July subtly transitions into the fall, September maintains a warm glow that invites visitors to revel in the scenic beauty of the area. Following this vibrant month, sunlight gently wanes, setting the stage for the cooler months ahead, with October and November showing a gradual decrease in sunshine. Overall, September stands as a golden bridge between the peak summer and the soothing embrace of autumn, creating the perfect ambiance for exploration and relaxation.
September in Co To, Vietnam, sees a moderate chance of sunny weather, with about 32% of the days likely to grace visitors with sunshine. This month marks a slight improvement compared to the preceding summer months, where the likelihood of clear skies plummets, reaching as low as 14% in August. However, September still indicates a notable dip from the sunnier months earlier in the year, such as February, which enjoys a robust 63% chance of sun. As autumn approaches, it's essential for travelers to embrace the varying weather and prepare for the refreshing yet unpredictable nature of Co To's September climate.
In September, the vibrant coastal town of Co To, Vietnam enjoys approximately 12 hours of daylight, maintaining a pleasant balance between light and twilight. This duration is a continuation of the summer warmth experienced in June, July, and August, where locals basked in the luxury of extended daylight. As the month transitions into autumn, daylight hours begin to taper off, reminiscent of April and May’s brighter spells. Overall, the trend showcases a gradual shift from longer days in the summer months to shorter daylight hours as the year draws to a close, creating a rhythm in nature that reflects the changing seasons.
As September arrives in Co To, Vietnam, the gentle caress of the wind becomes more noticeable, with an average speed of 3.7 m/s (8 mph), marking a dip from the summer's breezy peaks. This month often serves as a transition, where the once lively winds of June and July begin to mellow, inviting a serene ambiance perfect for reflective beach strolls. Interestingly, September's wind is among the calmest of the year, paving the way for a notable uptick in wind speeds in October, when gusts soar to 8.2 m/s (18 mph). This rhythmic pattern not only highlights the dynamic climate of Co To but also sets the stage for the more brisk and invigorating winds that follow, as the region shifts into the heart of autumn.
Weather in Co To varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Co To, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present starkly contrasting weather conditions. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), with an average of 28°C (83°F). This month is characterized by high humidity at 78% and significant rainfall, featuring 360 mm (14.2 in) of precipitation over 22 days. In contrast, January experiences much cooler temperatures, with minimums of 9°C (48°F), averages at 17°C (63°F), and maximums reaching only 22°C (72°F). Rainfall is minimal in January, totaling just 39 mm (1.5 in) across 8 days, and the humidity drops to 66%. For more details on the January climate, you can visit Co To weather in January.
September and February present stark contrasts in weather patterns. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), with an average of 28°C (83°F). This month also experiences significant rainfall, with 360 mm (14.2 in) of precipitation occurring over 22 days, leading to a high humidity level of 78%. In contrast, February sees much cooler conditions, with temperatures ranging from a low of 10°C (50°F) to a high of 22°C (73°F) and an average of 18°C (64°F). Precipitation is notably lower, at just 51 mm (2.0 in) over 8 days, accompanied by a slightly lower humidity of 71%. For more details on February weather, check Co To weather in February.
September and March exhibit contrasting weather patterns, showcasing the transition from the warmth of summer to the cooler beginnings of autumn. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), with an average temperature of 28°C (83°F). This month is marked by significant rainfall, accumulating 360 mm (14.2 in) over 22 days, leading to high humidity levels of 78%. In contrast, March features milder conditions, with temperatures ranging from 15°C (60°F) to 25°C (77°F) and an average of 21°C (69°F). Precipitation is considerably lower in March at 57 mm (2.2 in) over 12 days, along with a slightly lower humidity of 73%. For a detailed look at the weather specifics, check out Co To weather in March.
When comparing the weather in September and April, it's clear that September is characterized by warmer temperatures and higher humidity. With a minimum of 25°C (77°F) and an average of 28°C (83°F), September typically feels much hotter than April, where the minimum temperature is only 16°C (62°F) and the average reaches 23°C (74°F). Additionally, September experiences significantly more rainfall, receiving 360 mm (14.2 in) over 22 days compared to April's 91 mm (3.6 in) over just 12 days. This higher precipitation in September contributes to its greater humidity of 78%, while April maintains a more comfortable 71%. For a closer look at the weather in Co To during this month, visit Co To weather in April.
Comparing the weather in September and May reveals some interesting differences. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), with an average of 28°C (83°F). The month is quite wet, experiencing an average rainfall of 360 mm (14.2 in) over 22 days and humidity levels around 78%. In contrast, May sees slightly cooler temperatures, with a minimum of 20°C (68°F), an average of 27°C (80°F), and the same maximum of 31°C (88°F). Precipitation in May is significantly lower at 137 mm (5.4 in) over 16 days, and humidity is slightly less, at 76%. For more specific details about the weather in May, you can visit Co To weather in May.
In comparing the weather of September and June, we observe that both months feature consistently warm temperatures, with September averaging around 28°C (83°F) and June slightly warmer at 29°C (85°F). However, September tends to be wetter, accumulating 360 mm (14.2 in) of precipitation over 22 days, compared to June's 252 mm (9.9 in) over 19 days. Additionally, humidity levels are quite comparable, with September at 78% and June just a tad higher at 79%. For a more detailed look at June weather, you can visit Co To weather in June.
In comparison to July, September typically sees slightly lower temperatures, with average highs of 31°C (88°F) compared to July's 32°C (89°F). While both months experience considerable rainfall, September has a total precipitation of 360 mm (14.2 in) over 22 days, which is less than July's 435 mm (17.1 in) during the same number of days. Additionally, September tends to be less humid at 78% relative to July's higher humidity level of 86%. For a more detailed look at July's climate, you can check Co To weather in July.
In comparing the weather between August and September, September tends to be slightly cooler, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 31°C (88°F), while August showcases slightly higher temperatures with minima of 26°C (78°F) and maxima of 32°C (89°F). Additionally, September sees a significant drop in precipitation, with 360 mm (14.2 in) spread over 22 days compared to August's 594 mm (23.4 in) over 24 days. Humidity levels are also lower in September at 78%, down from August's 86%. For more details, you can check out Co To weather in August.
September and October exhibit notable differences in weather patterns. September tends to be warmer, with average temperatures peaking at 28°C (83°F) and a maximum of 31°C (88°F), while October cools slightly, with an average of 26°C (78°F). Additionally, September is marked by higher precipitation, totaling 360 mm (14.2 in) over 22 days compared to October’s 273 mm (10.8 in) over 16 days. Humidity also decreases from 78% in September to 72% in October, contributing to a more comfortable atmosphere as the month progresses. For more detailed information, check out Co To weather in October.
September weather is characterized by higher temperatures, with minimums around 25°C (77°F) and average highs reaching 31°C (88°F). This month also experiences significant rainfall, totaling 360 mm (14.2 in) over 22 days, alongside a high humidity level of 78%. In contrast, November sees a notable drop in temperature, with minimums around 15°C (59°F) and maximums of 27°C (80°F). The precipitation decreases dramatically to 39 mm (1.5 in), spread over just 9 days, and humidity levels fall to 69%. For more specific details on the conditions in November, you can check Co To weather in November.
In comparing the weather of September and December, a stark contrast emerges. September experiences much warmer temperatures, with a minimum of 25°C (77°F) and an average of 28°C (83°F), peaking at a sweltering 31°C (88°F). The month is also characterized by heavy rainfall, totaling 360 mm (14.2 in) over 22 days and high humidity levels at 78%. In contrast, December brings a significant drop in temperature, with a minimum of 11°C (51°F) and an average of 18°C (66°F), maxing out at 25°C (77°F). Rainfall is considerably lower, with only 49 mm (1.9 in) over 10 days, and humidity decreases to 70%. This shift from warm and wet to cool and dry marks a distinct seasonal transition. For more details, refer to Co To weather in December.
As September unfolds in Co To, the weather takes on a notably humid character, with increased rainfall that makes it distinct from other months. While temperatures remain comfortably warm, with averages around 28°C, the substantial precipitation—averaging 360 mm over 22 days—ushers in a lush, green landscape. This shift to a wetter climate enhances the island's natural beauty, inviting visitors to experience vibrant, post-rain settings. For more detailed insights on what to expect, explore the complete Co To Climate.