Last updated: August 27, 2025
In September, Mae Sai, Thailand experiences a tropical climate characterized by high temperatures and significant precipitation. Daily maximums can soar to 37°C (98°F), while the average temperature settles around a warm 27°C (81°F), providing a humid environment with levels reaching 85%. Rainfall is common, with 272 mm (10.7 in) accumulated over the month, typically spread across 23 days of rain. This combination of warmth and moisture contributes to the region's lush landscape, making September a vibrant, albeit wet, time to visit Mae Sai.
In September, Mae Sai, Thailand, experiences a pleasant transition in temperature, reflecting the tail end of the rainy season. With a minimum of 20°C (68°F) and an average of 27°C (81°F), the weather is comforting yet warm, making it ideal for exploring the lush landscapes. Maximum temperatures reach up to 37°C (98°F), indicating that while the days can still be hot, the humidity from the preceding rains adds a refreshing ambiance. Compared to the sweltering peaks of earlier months, September offers a respite, showing a slight dip in maximum temperatures and providing a more enjoyable atmosphere for both locals and visitors alike.
In September, Mae Sai, Thailand, experiences a significant dip in rainfall compared to the preceding months, receiving 272 mm (10.7 in) over approximately 23 days of precipitation. This marks a clear decrease from the peak rainfall months of June and August, which saw 348 mm (13.7 in) and 430 mm (16.9 in) respectively. The transition into September often signals a shift as the monsoon season begins to wane, yet the rain still provides a vital water source for the region. Despite the reduction in volume, the frequency of rainfall remains high, illustrating the lingering influence of the monsoon atmosphere. As Mae Sai gears up for a drier October, September serves as a bridge, hinting at the lush greenery nourished by its abundant rainfall earlier in the season.
In September, Mae Sai, Thailand, experiences a notable drop in humidity compared to the sweltering peaks of the previous months, though it remains elevated at 85%. The trend throughout the year showcases a gradual rise in humidity beginning in May, peaking in August at a staggering 92%. This gradual shift is characteristic of the region's transition from the dry heat of April, where humidity dips to 36%, to the intense monsoonal period of late summer. As the year progresses into fall, September maintains a significant level of moisture, hinting at the lingering effects of the rainy season. Following this month, humidity begins to decline more noticeably, dropping to 70% in October, indicating a shift towards drier conditions as the year continues.
As September rolls into Mae Sai, Thailand, the UV Index remains at a noteworthy 14, marking it as part of the extreme exposure category with a burn time of just 10 minutes. This trend of high UV levels, starting from March and continuing through October, paints a clear picture of the region's intense sun exposure. With consistent readings of 14 in the summer months, including September, residents and visitors alike should take precautions to protect their skin from harmful rays. As the year transitions from sweltering summer to the cooler months, the UV Index is likely to decline, but for now, it's essential to stay vigilant. For more insights into UV levels throughout the year, check the full details at Mae Sai UV Index.
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September shines warmly in Mae Sai, Thailand, offering 270 hours of sunshine that gently bridges the long, sun-kissed days of summer with the approaching fall. Comparatively, the month sees a slight dip from the vibrant heights of spring, particularly from March's peak of 328 hours. Despite this, September remains a splendid choice for those seeking to bask in a substantial amount of sunlight, comfortably higher than the rainfall-laden months of July and August. As the rainy season begins to wane, visitors are treated to a delightful blend of sunny days and cooler evenings, making this month perfect for exploring the lush landscapes and vibrant culture that Mae Sai has to offer.
In Mae Sai, Thailand, the month of September experiences a relatively modest 29% chance of sunny weather, making it one of the less favorable times for sunshine throughout the year. As the rainy season peaks, sunlight becomes scarce, especially when compared to the sun-drenched days of March, which boasts the highest chance at 82%. This trend continues into the summer months of April and May, where chances drop significantly to 41% and 39% respectively. While the clouds settle in and rain prevails during September, there is a slight uptick in sunny days as October moves in, hinting at the return of brighter skies. Overall, if you're planning a visit in September, be prepared for the likelihood of rain overshadowing sunbathing opportunities.
In Mae Sai, Thailand, September brings a return to a 12-hour daylight duration, echoing the consistency of the preceding months. As the year progresses, daylight stretches from 11 hours in January and February to a peak of 13 hours from May to July, providing longer evenings to savor the tropical ambiance. Following this peak, daylight begins to taper off, with September marking a transition towards the shorter days of autumn. The rhythmic fluctuations in daylight illustrate the region's moderate tropical climate, where the length of day closely aligns with seasonal changes, inviting residents and visitors alike to enjoy the vibrant natural beauty as the year begins to wind down.
As September rolls in Mae Sai, Thailand, the wind whispers a gentle lull, with an average speed of just 1.0 m/s (2 mph). This slight drop in wind strength continues the trend observed in the preceding months, where the breezes have been consistently mild, peaking only modestly at 1.4 m/s (3 mph) in June. The overall pattern reveals a subtle easing of winds from the early summer's gentle currents, providing a calm and serene atmosphere as the region transitions into the cooler months ahead. With such tranquility in the air, September invites residents and visitors alike to bask in the peaceful surroundings, making it an ideal time for outdoor exploration and relaxation.
Weather in Mae Sai varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Mae Sai, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is characterized by much higher temperatures, with a minimum of 20°C (68°F) and an average of 27°C (81°F), pushing up to a maximum of 37°C (98°F). This month also experiences significant rainfall, totaling 272 mm (10.7 in) over 23 days, resulting in high humidity levels of 85%. In stark contrast, January offers a cooler climate, with temperatures ranging from a minimum of 8°C (47°F) to an average of 20°C (68°F) and a maximum of 32°C (90°F). Precipitation is minimal in January, averaging just 44 mm (1.7 in) over 6 days, and the humidity drops to a more comfortable 54%. For more detailed insights, you can visit Mae Sai weather in January.
When comparing the weather in September and February, there is a noticeable contrast in temperature and precipitation. September experiences much warmer temperatures, with a minimum of 20°C (68°F) and an average of 27°C (81°F), rising to a maximum of 37°C (98°F). However, it is also quite humid, with an average humidity of 85% and significant rainfall totaling 272 mm (10.7 in) over 23 days. In contrast, February offers cooler temperatures, with a minimum of 10°C (50°F) and an average of 21°C (71°F), soaring to a maximum of 35°C (95°F). Furthermore, February is considerably drier, accumulating only 18 mm (0.7 in) of precipitation over just 2 days, and enjoying lower humidity levels at 52%. For further details on local conditions, you can check Mae Sai weather in February.
September and March showcase contrasting weather patterns. In September, temperatures range from a minimum of 20°C (68°F) to a scorching maximum of 37°C (98°F), with an average of 27°C (81°F). This month is characterized by high humidity at 85% and significant rainfall, totaling 272 mm (10.7 in) over 23 days. In contrast, March experiences milder temperatures, with a minimum of 11°C (52°F) and a maximum reaching 38°C (101°F), while averaging 25°C (77°F). The month sees much less precipitation, with only 17 mm (0.7 in) falling over just 3 days, and humidity levels drop to 40%. For more specific details, check out Mae Sai weather in March.
September and April exhibit distinct weather patterns. In September, temperatures range from a minimum of 20°C (68°F) to a maximum of 37°C (98°F), with an average of 27°C (81°F). This month is characterized by high precipitation, totaling 272 mm (10.7 in) over 23 days and a humidity level of 85%, creating a humid atmosphere. In contrast, April shows a slightly lower minimum temperature of 16°C (60°F) but can reach an impressive maximum of 40°C (105°F), also averaging 27°C (80°F). Rainfall is significantly lower in April, with only 125 mm (4.9 in) across 11 days and much lower humidity of 36%. For more details on April weather, you can visit Mae Sai weather in April.
In September, the weather tends to be more humid, with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 37°C (98°F) and an average of 27°C (81°F). This month also experiences significant rainfall, with 272 mm (10.7 in) of precipitation across 23 days, resulting in a high humidity level of 85%. In contrast, May offers slightly warmer temperatures, with a minimum of 20°C (69°F), an average of 28°C (82°F), and a peak of 41°C (107°F). Although May has less rainfall, with 167 mm (6.6 in) across 18 days, the humidity is considerably lower at 56%, creating a different atmosphere. For more details, you can check Mae Sai weather in May.
September and June share relatively warm temperatures, with September exhibiting a minimum of 20°C (68°F) and an average of 27°C (81°F), while June typically has a slightly higher minimum of 23°C (73°F) and an average of 28°C (82°F). Both months experience high humidity, yet September is slightly more humid at 85%, compared to June's 82%. Rainfall is also significant in both months, with September receiving 272 mm (10.7 in) over 23 days, while June sees an even greater precipitation of 348 mm (13.7 in) over 26 days. For more detailed information, you can check Mae Sai weather in June.
When comparing the weather between September and July, there are some notable differences and similarities. Both months have an average temperature of 27°C (81°F), reflecting a consistent warmth. However, September tends to be slightly cooler with a minimum temperature of 20°C (68°F), compared to July's minimum of 23°C (73°F). July also shows a higher maximum temperature of 38°C (100°F), while September peaks at 37°C (98°F).
In terms of precipitation, July is wetter, receiving 372 mm (14.7 in) over 28 days, in contrast to September's 272 mm (10.7 in) spread over 23 days. Additionally, humidity levels are higher in July at 90%, compared to 85% in September. For more detailed information, you can visit Mae Sai weather in July.
In comparing the weather conditions of September and August, both months showcase warm temperatures, with September experiencing slightly cooler minimum temperatures at 20°C (68°F) compared to August's 23°C (73°F). The average temperature remains consistent at 27°C (81°F), while September's maximum reaches 37°C (98°F), just above August's peak of 36°C (98°F). Despite the similarities in temperature, September records significantly less rainfall, with 272 mm (10.7 in) over 23 days, in contrast to August's 430 mm (16.9 in) accumulated over 27 rainy days. Additionally, humidity levels are slightly lower in September at 85%, compared to August's higher humidity of 92%. For more insights on August weather specifics, you can refer to Mae Sai weather in August.
In September, temperatures in Mae Sai range from a minimum of 20°C (68°F) to a maximum of 37°C (98°F), with an average temperature of 27°C (81°F). This month also experiences significant rainfall, totaling 272 mm (10.7 in) over 23 days, and a high humidity level of 85%. In contrast, October sees slightly cooler temperatures, with a minimum of 18°C (65°F), an average of 26°C (78°F), and a maximum of 35°C (94°F). The precipitation decreases to 158 mm (6.2 in) over 20 days, and humidity drops to 70%. For more detailed weather information, check out Mae Sai weather in October.
September weather tends to be much warmer and more humid compared to November, with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 37°C (98°F) and an average of 27°C (81°F). This month also experiences significant rainfall, with 272 mm (10.7 in) of precipitation spread over 23 days, leading to a high humidity level of 85%.
In contrast, November brings cooler temperatures, with a minimum of 14°C (57°F) and a maximum of 34°C (93°F), averaging around 23°C (74°F). The precipitation levels drop drastically to 49 mm (1.9 in) over just 9 days, and humidity decreases to 67%. For more detailed insights, you can check Mae Sai weather in November.
September and December showcase a stark contrast in weather patterns. September experiences much warmer temperatures, with averages around 27°C (81°F) and peaks reaching up to 37°C (98°F), accompanied by high humidity at 85%. This month also sees substantial rainfall, with 272 mm (10.7 in) of precipitation over 23 days. In contrast, December presents a cooler climate, with average temperatures dropping to 20°C (68°F) and maximums of 31°C (89°F). The month is significantly drier, with only 35 mm (1.4 in) of precipitation occurring over just 4 days and humidity levels decreasing to 62%. For more detailed insights, you can check out Mae Sai weather in December.
As September rolls in, Mae Sai experiences a notable shift in weather, marked by increased humidity and significant rainfall. With the maximum temperatures soaring to around 37°C, the city retains a tropical warmth, but the average temperatures drop to a comfortable 27°C, offering brief respite from the heat. The month is characterized by frequent rain, occurring on about 23 days, contributing to a total precipitation of 272 mm. This contrast in weather patterns not only enhances the lush greenery but also sets September apart as a month of transformation. For a deeper understanding of Mae Sai's climate throughout the year, visit Mae Sai Climate.