Last updated: August 27, 2025
September in Koh Tao, Thailand boasts a tropical atmosphere characterized by warm temperatures averaging around 28°C (82°F), with daily maxima reaching 30°C (86°F) and minima dipping to 26°C (78°F). Visitors can expect a lush and humid environment, as the island experiences an impressive 87% humidity. This month also marks a significant rainfall period, receiving approximately 192 mm (7.6 in) over 22 days, making it essential for travelers to prepare for intermittent showers. Despite the wet weather, Koh Tao's vibrant landscape and rich marine life continue to enchant those who seek an unforgettable experience.
September in Koh Tao, Thailand, showcases warm and inviting temperatures that perfectly encapsulate tropical bliss. With a minimum of 26°C (79°F) and an average hovering around 28°C (82°F), visitors can expect delightful days ideal for beach lounging or exploring underwater wonders. The maximum temperature reaches a comfortable 30°C (86°F), allowing for plenty of sunshine while maintaining a pleasant atmosphere. As the month transitions, these warm conditions continue the trend set by the preceding months, making September an enticing time for travelers seeking sun-soaked adventures in this picturesque paradise. Overall, the climate is balmy, providing an excellent backdrop for both relaxation and outdoor activities amidst Koh Tao's stunning scenery.
September marks a significant shift in Koh Tao's weather patterns, with precipitation levels peaking at 192 mm (7.6 in), making it one of the rainiest months of the year. This month typically experiences 22 days of rainfall, underscoring a trend towards increased moisture as the region transitions deeper into the monsoon season. Following a series of relatively dry months, the surge in rain not only replenishes the lush landscapes but also adds a dramatic flair to the island’s natural beauty. As rainfall intensifies, September sets the stage for even heavier downpours in October and November, indicating a notable pattern of increased precipitation that characterizes the latter part of the year. Visitors during this time may witness the vibrant transformations of Koh Tao, where rain showers create a refreshing ambiance amidst the lush surroundings.
In September, Koh Tao experiences a high humidity level of 87%, contributing to the tropical charm of this stunning island. The month marks a slight dip from the peak levels observed in August at 88%, yet the overall trend reveals a significant climb in humidity from the drier winter months. Starting January with a comfortable 72%, humidity steadily increases, peaking during the rainy season in August and September, creating a lush environment. Although October sees a gradual decrease to 86%, the residual moisture from September’s atmosphere lingers, ensuring Koh Tao remains vibrant and lush. Visitors should embrace the tropical humidity as part of the island's irresistible allure!
September in Koh Tao, Thailand, continues the trend of extreme UV exposure that characterizes the region throughout the year. With a consistent UV Index of 14, the conditions remain notably high, requiring sun-seekers to stay vigilant. Burn time remains rapid at just 10 minutes, stressing the need for proper sun protection. As summer transitions to fall, the UV Index gently tapers off; however, September’s readings indicate that precautions are still paramount. For more insights into UV levels throughout the year, visit Koh Tao UV Index.
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As summer gently fades into autumn, September in Koh Tao, Thailand, welcomes approximately 279 hours of glorious sunshine. This marks a slight dip from the vibrant summer months, yet still reflects the region’s abundance of light. After basking in the summer peak of 345 hours in March, the trend shows a gradual decrease in sunshine, with September offering a warm embrace as it transitions to October’s 286 hours. Even with this shift, the equatorial charm remains palpable, making September an inviting time for beach lovers and adventurers alike to soak up the tropical ambiance before the festivities of the year-end kick in.
In Koh Tao during September, the likelihood of sunny weather dips significantly, with only an 11% chance of sun, making it one of the cloudiest months of the year. This trend follows a gradual decline in sunny days from the peak of 60% in February to a mere 8% in August, indicating a shift towards the rainy season. As fall approaches, hope for sun becomes increasingly dim, setting the stage for overcast skies and occasional showers. Travelers hoping for beach days might want to consider earlier months for a brighter experience, as sunny weather is notably more prevalent from January to April.
In Koh Tao, Thailand, September enjoys a delightful 12 hours of daylight, a continuation of the steady light that characterizes the region during the summer months. As the year unfolds, daylight duration rises modestly from 11 hours in January and February to a peak of 12 hours from March through September. Following this sunny stretch, the daylight diminishes gradually, dipping back to 11 hours in October and remaining consistent through the end of the year. This trend highlights a tropical paradise where the lush landscapes bask in ample sunlight, creating the perfect backdrop for outdoor adventures and leisurely beach days throughout the rainy season.
As September settles over Koh Tao, the island experiences an average wind speed of 4.9 m/s (approximately 11 mph), marking a slight dip from the breezy heights of the summer months. Following the lively gusts of July and August, which reached 5.9 m/s and 5.3 m/s respectively, September's winds begin to mellow, creating a more tranquil atmosphere. This shift signifies the transitional phase as the island prepares for the milder conditions of October and November, both accompanying average speeds of 5.2 m/s and 5.5 m/s. Overall, the wind patterns in Koh Tao hint at a gentle descent from the summer’s energetic breezes, paving the way for a serene and pleasant climate that invites relaxation and exploration alike.
Weather in Koh Tao varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Koh Tao, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is typically warmer and more humid, with average temperatures around 28°C (82°F) and humidity levels reaching 87%. This month sees significant rainfall, averaging 192 mm (7.6 in) over approximately 22 days, creating a lush but wet environment. In contrast, January is slightly cooler with average temperatures of 27°C (81°F), and much lower humidity at 72%. Rainfall in January is also reduced, totaling 148 mm (5.8 in) over just 10 days, making it a more pleasant time for outdoor activities. For a more detailed look at January weather, check out Koh Tao weather in January.
In September, the weather is considerably warmer and more humid, with average temperatures ranging from a minimum of 26°C (78°F) to a maximum of 30°C (86°F) and an average humidity of 87%. This month also sees significant rainfall, with 192 mm (7.6 in) of precipitation spread across 22 days, making it a rather wet time of year.
In contrast, February offers a more pleasant climate, characterized by slightly cooler temperatures, with a minimum of 25°C (77°F) and a maximum of 29°C (85°F). The humidity drops to a more comfortable 68%, and there is significantly less rainfall, totaling only 37 mm (1.5 in) over just 7 days. For those interested in exploring the weather in greater detail, here's a link to Koh Tao weather in February.
In September, the weather is characterized by higher humidity levels at 87%, with temperatures ranging from a minimum of 26°C (78°F) to a maximum of 30°C (86°F), and an average of 28°C (82°F). This month experiences significant rainfall, totaling 192 mm (7.6 in) over 22 days. In contrast, March offers a slightly more comfortable climate, maintaining similar temperature ranges but with lower humidity at 68% and minimal precipitation of just 33 mm (1.3 in) over 6 days. For detailed insights, you can check Koh Tao weather in March.
In September, the weather tends to be quite humid and wet, with temperatures ranging from a minimum of 26°C (78°F) to a maximum of 30°C (86°F) and an average of 28°C (82°F). This month experiences 192 mm (7.6 in) of rainfall over 22 days, resulting in a high humidity level of 87%. In contrast, April portrays a more drier and slightly warmer climate, with temperatures ranging from a minimum of 25°C (78°F) to a maximum of 31°C (88°F), averaging 28°C (83°F). The precipitation in April is significantly less, at 133 mm (5.3 in) over just 16 days, and is accompanied by a lower humidity level of 69%. For further insights into April's weather, you can visit Koh Tao weather in April.
In comparing the weather conditions of September and May, both months showcase warm temperatures with minimal variation. September experiences slightly lower averages, featuring minimum temperatures around 26°C (78°F) and maximums reaching 30°C (86°F), while May offers a slightly warmer climate with average temperatures peaking at 31°C (89°F). Precipitation levels are notable in both months, with September receiving 192 mm (7.6 in) and May slightly less at 153 mm (6.0 in), though both months have a similar number of rainy days—22. Additionally, September tends to be more humid, with humidity levels at 87% compared to May's 77%. For a deeper dive into the weather patterns during this time, check out Koh Tao weather in May.
In comparing the weather of September and June, both months experience similar temperature ranges, with minimums around 26°C (78°F) and average temperatures close to 28°C (82°F). However, June tends to be slightly warmer with a maximum of 31°C (89°F), compared to September's peak of 30°C (86°F). Precipitation is notably higher in September, totaling 192 mm (7.6 in) over 22 days, compared to June’s 137 mm (5.4 in) across 19 days. Both months have high humidity levels, with September at 87% and June at 86%, making the atmosphere feel similarly muggy. For more detailed information about June weather specifically, you can check Koh Tao weather in June.
In comparing the weather of September and July, both months have similar temperature ranges, with September showing a min of 26°C (78°F), an average of 28°C (82°F), and a max of 30°C (86°F), while July experiences slightly higher maxima at 31°C (88°F). However, September is marked by significantly higher precipitation, totaling 192 mm (7.6 in) over 22 days, compared to July's 113 mm (4.4 in) over 19 days. Additionally, the humidity levels remain quite comparable, with September at 87% and July at 86%, making both months feel quite sticky. For a more detailed look at July weather, you can check this link: Koh Tao weather in July.
In comparing the weather between August and September, both months exhibit warm temperatures with minimal difference, as September's average temperature hovers around 28°C (82°F), slightly cooler than August's average of 28°C (83°F). Although the minimum temperatures remain similar at 26°C (78°F), September experiences a slightly lower maximum temperature of 30°C (86°F) compared to August's 31°C (88°F). Notably, September is characterized by significantly higher precipitation, with 192 mm (7.6 in) across 22 days, in contrast to August's 133 mm (5.2 in) over 21 days. Humidity levels are relatively consistent, with September at 87% and August at 88%. For more detailed insights about August weather, you can visit Koh Tao weather in August.
In September, the weather typically features warm temperatures with a minimum of 26°C (78°F) and an average of 28°C (82°F), peaking at 30°C (86°F). However, it also brings significant rainfall, recording 192 mm (7.6 in) over 22 days, and high humidity levels at 87%.
In contrast, October experiences slightly cooler temperatures, with a minimum of 25°C (77°F) and an average of 27°C (82°F), while the maximum remains the same at 30°C (86°F). The month is characterized by increased rainfall, totaling 242 mm (9.5 in) over 27 days, and humidity drops slightly to 86%.
For a detailed look at the weather trends, you can check out Koh Tao weather in October.
In September, the weather typically features a minimum temperature of 26°C (78°F), with an average of 28°C (82°F) and a maximum of 30°C (86°F). The month often experiences significant rainfall, with a total of 192 mm (7.6 in) spread across 22 days and humidity levels hovering around 87%.
In contrast, November sees slightly cooler temperatures, with a minimum of 25°C (77°F), an average of 27°C (82°F), and a maximum of 29°C (85°F). However, it is wetter, with precipitation rising to 281 mm (11.0 in) over the same number of rainy days, while humidity remains constant at 87%.
For more detailed insights into the weather conditions, you can check Koh Tao weather in November.
In September, the weather is typically warm and humid, with average temperatures around 28°C (82°F) and significant rainfall of 192 mm (7.6 in) spread over 22 days. The humidity is quite high at 87%, contributing to a tropical feel. In contrast, December offers slightly cooler temperatures, with an average of 27°C (81°F) and a reduction in precipitation to 191 mm (7.5 in) over just 14 days. The humidity also decreases to 83%, resulting in a more comfortable climate. For more details, you can check out the Koh Tao weather in December.
September in Koh Tao presents a distinct climate experience compared to other months, characterized by higher humidity and increased rainfall. With temperatures consistently warm, averaging around 28°C, visitors can expect a tropical atmosphere, though the frequent rain—spanning about 22 days—does bring an occasional respite from the heat. This month invites a sense of lushness to the island, making it a quieter time for travelers seeking a more serene escape. For those interested in understanding the broader climate trends, explore our detailed page on Koh Tao Climate.