Last updated: August 27, 2025
In September, Udon Thani experiences a blend of warm temperatures and significant humidity, with highs reaching up to 36°C (97°F) and an average of 28°C (83°F). The month is characterized by an abundance of precipitation, totaling 219 mm (8.6 in) over 24 days, contributing to the region’s lush landscape. With humidity levels soaring to 86%, visitors can expect a tropical atmosphere, perfect for exploring local culture and enjoying the vibrant surroundings, while also being prepared for frequent rain showers.
In September, Udon Thani experiences a gentle transition as temperatures start to cool slightly from the peak heat of summer. With a minimum temperature of 22°C (72°F) and a maximum reaching 36°C (97°F), the month offers a comfortable average of 28°C (83°F). Compared to the oppressive highs of April and May, where temperatures soared above 41°C (105°F), September provides a welcome reprieve. Humidity remains, but the slight dip in daytime temperatures, coupled with longer nights, signals the start of the cooler months ahead. This makes September an ideal time for outdoor exploration without the sweltering conditions typical of the earlier summer months.
In September, Udon Thani experiences a significant drop in precipitation compared to the previous month, receiving 219 mm (8.6 in) of rain over 24 days. This marks a shift from the highs of August, which recorded the year's peak rainfall of 319 mm (12.6 in). While September remains wet, with rainfall spread across nearly every day, it signals the approaching end of the monsoon season. The wet conditions contribute to the region's lush landscapes, but the decrease in both precipitation amount and days indicates a transition towards the drier months ahead. This month encapsulates the tail end of the heavy rainy season, as the community prepares for the relative dryness of October and beyond.
In September, Udon Thani experiences a notable drop in humidity compared to the peak levels seen in the summer months. Following the sweltering highs of August, with humidity reaching an impressive 92%, September settles at 86%, still high, but a reprieve for those accustomed to the oppressive moisture. The trend reveals a clear seasonal pattern, with humidity gradually rising from 40% in April to its summer peak, before starting a gradual decline into the drier months of autumn. As we transition into October, Udon Thani keeps some of September's residual humidity at 80%, hinting at the lingering effects of the rainy season while signaling the shift towards more comfortable conditions ahead.
In September, Udon Thani experiences a consistently extreme UV Index of 14, maintaining the high levels that have defined the region's summer months. This trend, rooted in the ongoing heat of the year, means that residents and visitors must be especially cautious, as the burn time is a mere 10 minutes. Following the peak months of June through August, September continues to demand protective measures against harmful UV exposure. As we transition into October, the UV Index will slightly drop, yet the extreme category is still present, indicating the ongoing need for vigilance. For more insights on UV levels throughout the year, check out the detailed Udon Thani UV Index.
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In Udon Thani, Thailand, September brings a pleasant transition into the cooler months with 279 hours of sunshine, slightly more than the previous month yet noticeably lower than the sun-drenched peak of 321 hours in March. This trend illustrates a gradual decline in sunshine leading into the late summer and early autumn, with August showing just 257 hours. However, September stands as a bright and inviting month, offering plenty of daylight for exploration and leisure before the sun shines even brighter again in October with 293 hours. As the year progresses, the pattern of longer sunlight hours returns, promising the vibrant energy of the upcoming months. The balance of warmth and comfort during this time makes September a delightful period to experience the region's cultural and natural beauty.
In Udon Thani, Thailand, the month of September presents a notably low 16% chance of sunny weather, continuing a trend of diminishing sunshine from the peak months of January through April. As the year unfolds, the probability of clear skies significantly drops, with the rainy season settling in during late summer. After the bright and warm days of early year, this decline highlights September as a particularly gloomy time, making it one of the least favorable months for sun seekers. Despite the subsequent rise in October, which reaches a 29% chance of sun, September remains a stark contrast to the vibrant beginnings of the year, serving as a reminder of the region's shifting climatic patterns.
In Udon Thani, Thailand, September marks a gentle transition in daylight duration, with the sun gracing the skies for 12 hours each day. This consistent daylight follows a summer peak, where June and July offer the maximum sunlight at 13 hours. As the year progresses, the days gradually shorten, with daylight levels dipping to 11 hours by October. Interestingly, September's daylight duration mirrors the vibrant months of March, April, and May, showcasing a sense of balance as it paves the way to the cooler months ahead. This rhythm of sunlight not only influences daily activities but also reflects the beautiful, cyclic nature of the seasons in this tropical paradise.
In September, Udon Thani experiences a gentle breeze, with an average wind speed of 1.7 m/s (4 mph). This marks a slight decrease from the summer months, where July and June maintained a steady 2.2 m/s (5 mph), offering more vigorous winds that help to slightly cut through the heat. As the region transitions into the latter part of the year, the winds begin to pick up again in October at 2.0 m/s (4 mph) and continue to strengthen into the cooler months. This pattern of fluctuating wind speeds reflects the unique climate of Udon Thani, where the breezes are mild yet refreshing, providing a pleasant interlude as the region prepares for the cooler, more dynamic months ahead.
Weather in Udon Thani varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Udon Thani, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present strikingly different weather patterns. September experiences much warmer temperatures, with a minimum of 22°C (72°F) and an average of 28°C (83°F), peaking at 36°C (97°F). It is also characterized by high humidity at 86% and significant precipitation, totaling 219 mm (8.6 in) over 24 days. In contrast, January features cooler temperatures, with a minimum of 10°C (50°F) and an average of 24°C (75°F), while still reaching a maximum of 35°C (96°F). The month is notably dry, with only 4 mm (0.1 in) of precipitation across just one day and a more comfortable humidity level of 59%. For a detailed look at the weather patterns during this month, check out Udon Thani weather in January.
September presents a markedly warmer and wetter climate compared to February. With temperatures ranging from a minimum of 22°C (72°F) to a maximum of 36°C (97°F), September enjoys an average temperature of 28°C (83°F) and experiences significant rainfall, totaling 219 mm (8.6 in) over 24 days. The humidity during this month climbs to a high 86%, making the air feel quite muggy.
Conversely, February boasts cooler temperatures with a minimum of 13°C (55°F) and a maximum reaching 37°C (100°F), resulting in an average of 25°C (77°F). Precipitation is minimal, amounting to only 12 mm (0.5 in) over just one day, and the humidity drops significantly to 54%. This drastic difference in weather patterns makes February much drier and more pleasant than the humid, rain-soaked September. For more details about the weather in February, you can visit Udon Thani weather in February.
When comparing the weather in September and March, there are notable differences in both temperature and precipitation. September tends to be quite warm, with average temperatures around 28°C (83°F) and maximums reaching up to 36°C (97°F). However, it is also marked by high humidity at 86% and significant rainfall, totaling 219 mm (8.6 in) over 24 days. In contrast, March features a similar average temperature of 28°C (83°F) but can experience extreme highs up to 40°C (104°F). March is characterized by much lower humidity at 45% and minimal precipitation, with only 34 mm (1.3 in) over just 6 days. For more detailed information regarding March weather, you can refer to Udon Thani weather in March.
When comparing the weather in September and April, notable differences emerge. September experiences warmer temperatures with an average of 28°C (83°F), reaching a high of 36°C (97°F), and is characterized by high humidity at 86%. In contrast, April sees slightly cooler average temperatures at 29°C (85°F), but can peak at an extreme 41°C (107°F). April is significantly drier, with only 69 mm (2.7 in) of precipitation over 9 days, compared to September's 219 mm (8.6 in) across 24 days. For more detailed information about April weather in Udon Thani, you can visit Udon Thani weather in April.
In comparing the weather of September and May, it’s evident that both months have a minimum temperature of 22°C (72°F); however, May typically enjoys a higher average temperature of 30°C (85°F) compared to September's 28°C (83°F). The peak temperatures in May can soar up to 41°C (105°F), significantly warmer than September's maximum of 36°C (97°F). Precipitation is also a factor, with September experiencing more rainfall at 219 mm (8.6 in) over 24 days, while May sees 183 mm (7.2 in) over 18 days. Additionally, September's high humidity of 86% contrasts with May's more comfortable 65%. For a closer look at May’s weather conditions, check out Udon Thani weather in May.
In comparing the weather between September and June, September tends to be slightly cooler with average temperatures ranging from a minimum of 22°C (72°F) to a maximum of 36°C (97°F), while June features a slightly higher range with minimums of 24°C (75°F) and maximums reaching up to 38°C (100°F). Precipitation levels are relatively close, with September receiving 219 mm (8.6 in) over 24 days and June experiencing slightly less at 206 mm (8.1 in) over 22 days. Additionally, humidity levels are a bit higher in September at 86%, compared to June's 82%. For those wishing to learn more about June weather specifics in Udon Thani, they can visit Udon Thani weather in June.
In comparing the weather of September to July, we see a slight decrease in temperature. September features a minimum of 22°C (72°F), an average of 28°C (83°F), and a maximum of 36°C (97°F), while July is warmer with a minimum of 24°C (76°F), an average of 29°C (84°F), and a maximum of 37°C (99°F). Precipitation is notable in both months, with September receiving 219 mm (8.6 in) over 24 days, whereas July is wetter with 289 mm (11.4 in) across 26 days. Humidity levels are also higher in July at 90%, compared to September's 86%. For more details, check Udon Thani weather in July.
In comparing the weather of September and August, both months experience warm temperatures, but September sees slightly cooler min and max temperatures with a range from 22°C (72°F) to 36°C (97°F), compared to August's higher range of 24°C (75°F) to 37°C (99°F). Precipitation levels also drop in September, totaling 219 mm (8.6 in) over 24 days, while August is much wetter with 319 mm (12.6 in) over 25 days. The humidity is also a bit lower in September at 86%, compared to August's 92%. For more details on the weather patterns during this month, you can visit Udon Thani weather in August.
September and October weather in Udon Thani show notable differences, despite similar maximum temperatures reaching up to 36°C (97°F) in both months. In September, the average temperature is slightly higher at 28°C (83°F), while October sees a dip to an average of 27°C (81°F). Precipitation also varies significantly; September experiences 219 mm (8.6 in) of rainfall over 24 days, whereas October receives only 114 mm (4.5 in) across 15 days. Additionally, October's humidity is lower at 80% compared to September's 86%, contributing to a more comfortable atmosphere. For more detailed information, you can check Udon Thani weather in October.
September and November showcase distinct differences in weather patterns. In September, temperatures range from a minimum of 22°C (72°F) to a maximum of 36°C (97°F), with an average of 28°C (83°F). The month is marked by significant rainfall, totaling 219 mm (8.6 in), spread over 24 days, contributing to a high humidity level of 86%. In contrast, November experiences a cooler climate, with temperatures dropping to a minimum of 16°C (62°F) and an average of 26°C (79°F), while still reaching highs of 36°C (97°F). Precipitation drastically declines to just 11 mm (0.4 in) over 2 days, resulting in lower humidity at 72%. For more details, see Udon Thani weather in November.
September and December present contrasting weather patterns. September features much warmer temperatures, with a minimum of 22°C (72°F) and an average of 28°C (83°F), peaking at a high of 36°C (97°F). This month is also characterized by significant rainfall, accumulating 219 mm (8.6 in) over 24 days and high humidity at 86%. In stark contrast, December has cooler temperatures, with a minimum of 9°C (49°F), an average of 23°C (74°F), and a maximum of 34°C (93°F). Additionally, December is notably drier, receiving only 6 mm (0.2 in) of precipitation over just 1 day, accompanied by lower humidity levels at 66%. For a detailed look at the weather in December, check out Udon Thani weather in December.
September in Udon Thani marks a distinct shift in the weather pattern, characterized by increased humidity and frequent rainfall. With nearly 24 days of precipitation, the month stands out from the drier and hotter months preceding it, presenting a vibrant yet often wet atmosphere. Temperatures remain warm, hovering around an average of 28°C, but the combination of high humidity—around 86%—and substantial rainfall at 219 mm creates a unique tropical feel. As the region transitions into the rainy season, visitors should be prepared for both the heat and unexpected showers. For more insights on weather patterns throughout the year, explore Udon Thani Climate.