Last updated: August 27, 2025
In September, Chiang Khong experiences a tropical climate characterized by a maximum temperature reaching up to 35°C (96°F) and an average of 27°C (81°F). The weather is notably humid, with levels averaging around 83%, contributing to a warm yet sultry atmosphere. Visitors should anticipate considerable rainfall, with an impressive total of 199 mm (7.8 in) spread over 23 days, making it one of the wetter months in the region. As the lush landscapes come alive, this month's dynamic weather paints a vivid backdrop for exploring this charming town.
In September, Chiang Khong experiences a pleasant yet warm climate, with temperatures ranging from a minimum of 19°C (67°F) to a comfortable maximum of 35°C (96°F). The average temperature hovers around 27°C (81°F), reflecting a transition from the blazing heat of summer towards the cooler months ahead. Although the region maintains a warm feel, there's a notable drop from the previous peak summer temperatures, suggesting a slight reprieve from the heat as the rainy season begins to taper off. This month marks the tail end of the wet season, and visitors can expect a blend of warm days and the lingering freshness of recent rains, making it an ideal time for outdoor adventures and exploring the lush surroundings.
In September, Chiang Khong experiences a significant amount of rainfall, totaling 199 mm (7.8 in) over approximately 23 days, continuing the trend of the region's wet season. Following the heavy downpours of August, with its record 373 mm, September's precipitation marks a notable decrease yet remains substantial, indicating that the monsoon influence persists strongly. This month often transitions towards drier periods with October showing a sharp dip to 113 mm, but the lush landscapes nurtured by September's rains provide a vibrant backdrop for the local ecology and agriculture. The pattern of frequent rainfall in the late monsoon showcases Chiang Khong's unique climatic rhythm, making it a captivating destination for nature enthusiasts.
In September, Chiang Khong experiences a significant increase in humidity as the rainy season approaches, with levels reaching 83%. This marks a return to the high humidity levels characteristic of the summer months, contrasting sharply with the drier conditions of April and May, which at their lowest dipped to 41% and 60%, respectively. The trend throughout the year highlights a distinct shift: early months like January and February maintain a comfortable 57%, but from June onwards, humidity consistently climbs, peaking at an impressive 92% in both July and August. As the year progresses into October, humidity remains relatively high but begins to taper off to 71%, indicating a gradual transition from the peak rainy season. This pattern reflects the tropical climate's influence on the region, shaping both the environment and daily life in Chiang Khong.
As September approaches in Chiang Khong, Thailand, the UV Index remains at a striking 14, placing it in the extreme exposure category—a continuation of the intense levels observed from May through August. During this month, sun exposure can lead to skin damage in just 10 minutes, underscoring the importance of sun safety. This trend of consistently high UV readings signals that visitors and locals alike should take precautions against the sun's rays. As we transition into October, we're reminded that the UV Index will only slightly decrease to 13, yet it remains crucial to stay vigilant in sun protection. For detailed insights on UV levels throughout the year, check out Chiang Khong UV Index.
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In September, Chiang Khong basks in a delightful 272 hours of sunshine, marking a subtle decline from the peak brightness of the earlier months. This month, the golden rays still outshine the tail end of the wet season, making it a perfect time for exploration before the cooler breezes of October sweep in with 287 hours of sun. As summer transitions away, sunshine gradually wanes from the record highs of March and April, which boast over 300 hours, yet September retains a charming warmth that encourages both relaxation and adventure. As the year progresses, visitors can anticipate a steady return to more radiant skies in the autumn months.
In Chiang Khong, Thailand, the likelihood of sunny weather sees notable fluctuations throughout the year. As September approaches, the chances for sun drop significantly to 29%, reflecting the onset of the rainy season that has been prevalent since June. This trend of diminishing sunshine continues from April’s 41% to May’s 40%, before hitting a low in the subsequent summer months. Surprisingly, September’s sun probability is much lower than the beginning of the year, where sunshine reigns with peaks in March (83%) and January (67%), suggesting that if you're planning a trip during this time, it's wise to prepare for a mix of rain and clouds rather than all-day sunshine.
In Chiang Khong, Thailand, the daylight duration exhibits a captivating rhythm as the year progresses. Starting with a steady 11 hours in both January and February, the days gradually stretch, reaching a peak of 13 hours from May to July. This increase highlights the vibrant energy of the summer months, where the longer days invite outdoor adventures and exploration. As we transition into August, daylight begins to recede slightly, settling back to 12 hours. By September, the trend continues, maintaining that same length of daylight before dipping to 11 hours in the following months. This pattern reflects the changing seasons and offers a beautiful reminder of nature's cyclical dance, making each month in Chiang Khong uniquely enchanting.
As September rolls into Chiang Khong, the wind takes on a gentle whisper, averaging a modest 1.1 m/s (2 mph)—a dip from the breezier months that preceded it. Throughout the year, wind speeds tend to build from the calmness of January's 1.3 m/s (3 mph) to a peak in June at 1.8 m/s (4 mph), creating a noticeable rhythm of seasonal change. However, as the monsoon retreats and autumn approaches, September's winds soften, hinting at the transition to a quieter, more tranquil atmosphere. This mellow breeze invites you to savor the beauty of the surroundings, offering a perfect backdrop for reflection and exploration in this charming Thai town.
Weather in Chiang Khong varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Chiang Khong, focusing on differences in temperature, rainfall, humidity, and UV levels.
In comparing the weather of September and January, we see a striking contrast. September's temperatures range from a warm minimum of 19°C (67°F) to a sweltering maximum of 35°C (96°F), averaging around 27°C (81°F). Coupled with high humidity at 83% and substantial precipitation of 199 mm (7.8 in) over 23 rainy days, September feels quite muggy and wet. In stark contrast, January offers cooler conditions with temperatures ranging from a low of 9°C (48°F) to a high of 33°C (91°F), averaging 21°C (69°F). The month is far drier, with only 34 mm (1.3 in) of rain falling over just 4 days, resulting in a more comfortable humidity level of 57%. For a detailed look at weather specifics in January, check out Chiang Khong weather in January.
When comparing the weather between September and February, September is characterized by significantly warmer temperatures, with averages around 27°C (81°F) and a maximum of 35°C (96°F), while February's temperatures are cooler, averaging 22°C (72°F) with a similar maximum of 35°C (95°F). September also experiences much higher precipitation, with 199 mm (7.8 in) falling over 23 days, leading to a humid environment at 83%. In contrast, February enjoys drier conditions, with only 16 mm (0.6 in) of rain falling over just 1 day, resulting in a more comfortable humidity level of 57%. For more information on February weather specifics, check out Chiang Khong weather in February.
In comparing the weather between September and March, we see distinct differences. September brings warmer temperatures with a minimum of 19°C (67°F) and an average of 27°C (81°F), peaking at 35°C (96°F). However, it is also characterized by heavy rainfall, experiencing 199 mm (7.8 in) of precipitation over 23 days, and high humidity at 83%. In contrast, March offers a cooler start with a minimum temperature of 13°C (56°F) and an average of 26°C (79°F), while reaching a maximum of 39°C (102°F). Precipitation during this month is significantly lower at just 11 mm (0.4 in), over only 2 days, and the humidity drops to 48%. For a more detailed look, you can check Chiang Khong weather in March.
When comparing the weather in September and April, we see distinct variations in temperature and precipitation. In September, the minimum temperature is slightly warmer at 19°C (67°F), with an average of 27°C (81°F) and a maximum reaching up to 35°C (96°F). The humidity is quite high at 83%, contributing to a muggy atmosphere. Conversely, April boasts a minimum temperature of 16°C (61°F) and a higher maximum of 39°C (103°F), while maintaining the same average of 27°C (81°F). Notably, April experiences significantly less rainfall, with only 120 mm (4.7 in) over 9 days compared to September's 199 mm (7.8 in) over 23 days. You can read more about the conditions in April here: Chiang Khong weather in April.
When comparing the weather in September and May, it's clear that both months present distinct characteristics. September tends to be slightly cooler, with average temperatures ranging from a minimum of 19°C (67°F) to a maximum of 35°C (96°F), while May showcases higher temperatures, peaking at an impressive 41°C (106°F). Additionally, September experiences significantly more rainfall, totaling 199 mm (7.8 in) over 23 days, compared to May's 114 mm (4.5 in) over just 13 days. In terms of humidity, September is considerably more humid at 83%, while May, with 60% humidity, feels relatively drier. For more detailed information about May weather, you can visit Chiang Khong weather in May.
In comparison to June, September experiences slightly cooler temperatures, with average highs of 35°C (96°F) compared to June's peak of 38°C (101°F). However, September is characterized by slightly more humidity at 83%, while June's humidity hovers around 80%. Both months face significant rainfall, with September receiving 199 mm (7.8 in) over 23 days and June totaling 229 mm (9.0 in) across 25 days. This makes both months quite wet, but June typically sees more precipitation overall. For those looking to understand the specifics of June weather, detailed information can be found here: Chiang Khong weather in June.
When comparing the weather in September and July, September tends to be slightly cooler, with average temperatures ranging from a minimum of 19°C (67°F) to a maximum of 35°C (96°F). In contrast, July boasts higher minimum temperatures of 23°C (73°F) and can reach highs of 39°C (103°F). Both months experience significant rainfall, but July is notably wetter, with 286 mm (11.3 in) of precipitation over 26 days, compared to September's 199 mm (7.8 in) across 23 days. Humidity levels are also higher in July at 92%, compared to September's 83%. For a detailed look at July conditions, you can check Chiang Khong weather in July.
In comparing the weather between September and August, we see some notable differences. September experiences a minimum temperature of 19°C, making it slightly cooler than August, which has a minimum of 23°C. However, both months share the same average and maximum temperatures, holding steady at 27°C and 35°C respectively. Precipitation in September totals 199 mm over 23 days, significantly less than the 373 mm accumulated over 27 days in August, indicating that September tends to be a drier month. Additionally, humidity levels drop from 92% in August to 83% in September, making the latter feel a bit more comfortable. For a detailed look at the August weather, you can visit Chiang Khong weather in August.
In September, the weather is characterized by warmer temperatures, with minimums around 19°C (67°F) and averages reaching up to 27°C (81°F), alongside maximums that can rise to 35°C (96°F). This month also sees a significant amount of rainfall, totaling 199 mm (7.8 in) over 23 days, contributing to a high humidity level of 83%. Conversely, October brings slightly cooler temperatures, with minimums of 17°C (62°F) and an average of 26°C (79°F), while the maximum temperature can still reach a similar peak of 36°C (96°F). Rainfall decreases considerably to 113 mm (4.4 in) over just 16 days, resulting in a more comfortable humidity level of 71%. For those interested in detailed October weather patterns, check out this link: Chiang Khong weather in October.
In September, the weather is significantly warmer and more humid, with temperatures ranging from a minimum of 19°C (67°F) to a scorching maximum of 35°C (96°F). This month also experiences considerable rainfall, totaling 199 mm (7.8 in) over 23 days, resulting in an average humidity of 83%. In contrast, November offers a cooler and drier climate, with temperatures dropping to a minimum of 14°C (57°F) and an average of 24°C (75°F), peaking at 34°C (93°F). Precipitation is much less in November, totaling only 29 mm (1.1 in) over 6 days, contributing to a lower humidity level of 68%. For more details on weather conditions, you can visit Chiang Khong weather in November.
September and December weather exhibit significant contrasts. In September, temperatures range from a minimum of 19°C (67°F) to a maximum of 35°C (96°F), accompanied by high humidity at 83% and considerable rainfall, with 199 mm (7.8 in) over 23 days. In stark contrast, December sees cooler temperatures, with a minimum of 5°C (42°F) and a maximum of 32°C (90°F), and is considerably drier, experiencing only 26 mm (1.0 in) of precipitation over just 4 days. The lower humidity in December, at 64%, further accentuates the more comfortable and pleasant conditions compared to the muggy and wet atmosphere of September. For more details on December weather, visit Chiang Khong weather in December.
In September, Chiang Khong experiences a notable shift in weather patterns. As the region welcomes the monsoon season, the humidity soars, creating a distinctly tropical feel. Rainfall becomes a regular occurrence, with precipitation gracing most days of the month, leading to an atmospheric transformation compared to the drier months. While temperatures remain warm, the presence of persistent rain often cools the air, providing a refreshing contrast to the sweltering heat felt earlier in the season. For those looking to understand more about the intricacies of weather in this scenic location, check out Chiang Khong Climate.