Last updated: August 27, 2025
September in Chiang Rai, Thailand is characterized by warm temperatures and high humidity, making it a vibrant and lush month. With maximum temperatures reaching 35°C (96°F) and an average of 26°C (80°F), visitors can expect tropical warmth, while minimums dip to a comfortable 20°C (68°F) at night. However, it’s also the peak of the rainy season, with precipitation totaling 260 mm (10.2 in) across 24 rainy days, resulting in a lush, green landscape. Travelers should be prepared for the high humidity, averaging 83%, making this month both challenging and enchanting for those who embrace the monsoon atmosphere.
In September, Chiang Rai experiences a shift in temperature as the rainy season continues, with minimums hovering around 20°C (68°F) and averages settling at a comfortable 26°C (80°F). This transitional month features max temperatures reaching 35°C (96°F), slightly more moderate compared to the scorching highs of previous months. The overall trend reflects a gradual cooling as the region moves toward the end of the monsoon season, making it an ideal time for travelers to enjoy the lush, green landscapes without the sweltering heat of summer. The temperature stability also invites outdoor exploration, allowing visitors to soak in the rich culture and stunning scenery of this enchanting city.
In September, Chiang Rai experiences significant rainfall, with 260 mm (10.2 in) of precipitation recorded over 24 days. This month is part of the region's peak monsoon season, following the heavy downpours of August, which sees the highest rainfall of the year. The trend shows that as the wet season progresses from May to September, precipitation amounts typically escalate, peaking in August before slightly diminishing in October. Despite a reduction in rainfall compared to August, September still delivers substantial moisture, making it a lush and vibrant time for the area's natural landscapes. Visitors during this period can expect frequent yet refreshing rain showers, contributing to the region's rich greenery and dynamic scenery.
In September, Chiang Rai experiences a notable shift in humidity, maintaining a high level of 83% that is typical for the late monsoon season. This is a slight decline from the previous month of August, which records an even higher humidity at 91%. The trend leading into September showcases a steady increase in humidity from May through to August, reflecting the region's abundant rainfall during these months. Following September, humidity is expected to decrease significantly as the dry season approaches, with October seeing a drop to 67%. This pattern illustrates the characteristic climatic fluctuations of Chiang Rai, where the wet months culminate in a peak before transitioning to a drier season.
As September rolls into Chiang Rai, the UV Index remains consistently high at 14, categorizing it as extreme and demanding caution from sun lovers. With a burn time of just 10 minutes, it mirrors the intense levels of sunlight seen throughout the preceding months of June, July, and August, which also recorded a UV Index of 14. This trend underscores the tropical climate's potent sun exposure, particularly during the peak months of early summer. Travelers and residents alike should remain vigilant and take necessary precautions, as the danger of sunburn is ever-present in this vibrant region. For more insights on sun safety, check out the detailed guide on Chiang Rai UV Index.
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September in Chiang Rai, Thailand, welcomes a delightful tapestry of sunshine with 275 hours of glorious daylight, bridging the transition from the lush monsoon months to the drier, golden days ahead. This period marks a subtle shift as the hours of sunlight begin to increase once again, following the lower counts of August. Comparatively, the sunshine in September provides a perfect balance, with hours similar to those of June and July, yet it hints at the vibrant energy of October and November ahead. As the rain begins to recede, this month invites travelers to bask in the gentle glow of the early autumn sun, making it an ideal time for exploration and outdoor activities in this enchanting Thai region.
As September rolls into Chiang Rai, Thailand, the chance of basking in sunny weather dips to 27%, a modest increase compared to the rainy months of June, July, and August, which plummet to a mere 11%, 15%, and 13% respectively. The trend reveals that as the region transitions from the sweltering heat of the earlier months to the onset of the rainy season, sunshine becomes increasingly elusive. While January through April boasts significantly higher sun chances—reaching peaks of 69% to 80%—September's prospects remind us that, despite the lush green landscapes nurtured by the rains, glimpses of sunshine are still sporadic. Travelers should prepare for both rain and sun, as the natural beauty of Chiang Rai continues to flourish in this transitional month.
In September, Chiang Rai experiences a moderate 12 hours of daylight, marking a transition as the sunny months begin to wane. Following the peak 13 hours of sunlight in May through July, the daylight duration gradually tapers off. This pattern signifies the shift towards the cooler season, as daylight hours decrease with the approach of October. Throughout the year, Chiang Rai showcases a delightful balancing act between longer summer days and shorter winter months, creating a rhythm that invites both exploration and relaxation amidst its stunning landscapes and vibrant cultures.
As September unfolds in Chiang Rai, Thailand, the gentle whisper of the wind becomes a defining feature of the landscape. With an average wind speed of just 1.1 m/s (2 mph), this month witnesses the softest breezes of the year, providing a tranquil backdrop amidst the lush greenery. Compared to the slightly brisker months of June and July, which enjoy speeds of 1.6 m/s (4 mph) and 1.4 m/s (3 mph) respectively, September's winds are a subtle reminder of the approaching transition to the cooler months. The overall trend throughout the year showcases a gradual fluctuation, with the softer gusts visible in late summer, hinting at a gentle shift from the vibrant heat of earlier seasons towards the refreshing embrace of autumn. This serene climate makes September an ideal time for outdoor activities, allowing visitors to fully appreciate the natural beauty of the region.
Weather in Chiang Rai varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Chiang Rai, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is significantly warmer and more humid than in January, with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 35°C (96°F) and an average of 26°C (80°F). The month is also characterized by high precipitation, totaling 260 mm (10.2 in) spread over 24 days, leading to a stifling humidity level of 83%. In contrast, January presents a much cooler climate, with temperatures dipping to a minimum of 7°C (46°F) and peaking at 33°C (91°F), while maintaining a milder average of 20°C (69°F). The precipitation in January is notably lower at 39 mm (1.5 in) over just 4 days, resulting in a much less humid atmosphere at 51%. For more detailed information, you can check Chiang Rai weather in January.
September and February present stark contrasts in weather conditions. September typically experiences warmer temperatures, with a minimum of 20°C (68°F) and an average high of 35°C (96°F), making it a hot and humid month with 83% humidity and substantial rainfall of 260 mm (10.2 in) spread over 24 days. In contrast, February offers cooler temperatures, with a minimum of 10°C (51°F) and an average peak of 35°C (96°F), but significantly less precipitation at just 16 mm (0.6 in) and only 1 rainy day, accompanied by a much lower humidity of 46%. These variations highlight February as a drier and more comfortable month compared to the wet and humid September. For more details on February weather, you can check Chiang Rai weather in February.
September and March exhibit striking differences in weather patterns. September is characterized by high temperatures ranging from a minimum of 20°C (68°F) to a maximum of 35°C (96°F), coupled with significant rainfall totaling 260 mm (10.2 in) over 24 days, resulting in a humid atmosphere with 83% humidity. In contrast, March showcases a more moderate climate with temperatures varying from a low of 12°C (53°F) to a scorching high of 39°C (102°F). Notably, March experiences far less precipitation, with only 13 mm (0.5 in) falling over just 2 days, leading to a much drier environment with humidity levels at 38%. For more details on the weather in March, visit Chiang Rai weather in March.
When comparing September and April weather, we see notable differences in temperature and precipitation. September experiences a minimum temperature of 20°C (68°F) with an average of 26°C (80°F) and can reach highs of 35°C (96°F). The month is characterized by significant rainfall, amounting to 260 mm (10.2 in) over 24 days, along with high humidity levels at 83%. In contrast, April presents a warmer profile, with minimum temperatures around 16°C (61°F), an average temperature of 27°C (80°F), and the potential for scorching highs of 40°C (105°F). Precipitation is much lower in April, totaling 171 mm (6.7 in) spread across just 13 days, and the humidity drops significantly to 36%. For a more detailed overview of the weather variations, you can check Chiang Rai weather in April.
In comparing the weather between September and May, both months experience warm temperatures, but May typically showcases a higher maximum at 41°C (106°F) compared to September's maximum of 35°C (96°F). While September sees an average temperature of 26°C (80°F) with significant humidity at 83% and frequent rainfall totaling 260 mm (10.2 in) over 24 days, May displays a slightly higher average temperature of 27°C (82°F) but with noticeably less humidity at 63% and less precipitation at 203 mm (8.0 in) over 19 days. For a more detailed look at May's weather in Chiang Rai, you can visit Chiang Rai weather in May.
In September, temperatures in Chiang Rai range from a minimum of 20°C (68°F) to a maximum of 35°C (96°F), averaging around 26°C (80°F). The month sees significant rainfall, with 260 mm (10.2 in) of precipitation spread over 24 days and a humidity level of 83%. In contrast, June experiences slightly warmer temperatures, with a minimum of 23°C (73°F) and a maximum of 37°C (99°F), averaging 27°C (81°F). June also records higher precipitation totals at 277 mm (10.9 in) over 25 days, with a slightly lower humidity of 81%. These differences highlight that while both months are characterized by humidity and rainfall, June tends to be warmer with more intense heat, whereas September has a more moderate temperature range with a high level of moisture. For more detailed insights, you can visit Chiang Rai weather in June.
In comparing the weather of September and July, we find that July tends to be slightly warmer, with average temperatures reaching 27°C (81°F) and a maximum of 37°C (98°F), compared to September's average of 26°C (80°F) and maximum of 35°C (96°F). However, July also experiences higher precipitation, with 327 mm (12.9 in) of rain spread over 27 days, while September sees 260 mm (10.2 in) with rain on 24 days. Both months share a high humidity level of 83%, contributing to a humid environment throughout. For more specific details about July's weather, you can visit Chiang Rai weather in July.
In comparing the weather of September and August, September experiences slightly cooler temperatures with a minimum of 20°C (68°F) and an average of 26°C (80°F), while August has a minimum of 23°C (73°F) and an average of 27°C (80°F). Both months reach similar maximum temperatures of 35°C (96°F) and 36°C (96°F) respectively, but September sees reduced precipitation at 260 mm (10.2 in) over 24 days, compared to August's 382 mm (15.1 in) over 28 days. Additionally, humidity is slightly lower in September at 83%, compared to August's 91%. For more detailed weather information, you can visit Chiang Rai weather in August.
In September, the weather is noticeably warmer with temperatures ranging from a minimum of 20°C (68°F) to a maximum of 35°C (96°F) and an average of 26°C (80°F). The month also sees significant rainfall, with precipitation totaling 260 mm (10.2 in) over 24 days, contributing to high humidity levels of 83%. In contrast, October experiences slightly cooler temperatures, with a minimum of 18°C (65°F), an average of 25°C (78°F), and a maximum of 34°C (93°F). Additionally, the precipitation decreases to 161 mm (6.3 in) over 19 days, and humidity drops to 67%. For more details, check the Chiang Rai weather in October.
In comparing the weather between September and November, September experiences warmer temperatures with a minimum of 20°C (68°F) and an average of 26°C (80°F), peaking at a high of 35°C (96°F). This month is notably wet, with 260 mm (10.2 in) of precipitation spread over 24 days and high humidity levels at 83%. In contrast, November brings a cooler climate, with a minimum of 13°C (57°F) and an average temperature of 23°C (74°F), reaching a maximum of 33°C (93°F). The precipitation significantly decreases to 48 mm (1.9 in) over just 9 days and humidity drops to 60%. The transition from September to November offers a noticeable shift in weather conditions, indicative of the changing seasons. For more details, check Chiang Rai weather in November.
In September, temperatures range from a warm 20°C (68°F) at night to a high of 35°C (96°F) during the day, with an average temperature of 26°C (80°F). The month is characterized by significant rainfall, receiving 260 mm (10.2 in) spread over 24 days, and high humidity levels at 83%, creating a muggy atmosphere. In stark contrast, December experiences cooler temperatures, with a minimum of 7°C (45°F) and a maximum of 32°C (90°F), averaging around 20°C (68°F). The rainfall drops dramatically to just 33 mm (1.3 in) over 4 days, and humidity levels decrease to a more comfortable 56%. For a detailed look at December's weather, you can check Chiang Rai weather in December.
As September rolls into Chiang Rai, the weather transforms distinctly, making it one of the wettest months of the year. With high humidity hovering around 83% and significant rainfall occurring on nearly every other day, this month experiences a marked increase in precipitation compared to the drier months surrounding it. Although temperatures remain pleasantly warm, with averages around 26°C (80°F), the frequent downpours create a lush, vibrant landscape that sets September apart. Whether you enjoy the rich greenery or prefer to explore the cultural treasures of the area, the unique charm of Chiang Rai's September weather offers an experience like no other. For a deeper understanding of the region's climate, visit Chiang Rai Climate.