Last updated: August 28, 2025
In September, Khe Sanh, Vietnam, experiences a lush and humid climate characterized by temperature extremes and significant rainfall. Daily maximum temperatures reach up to 35°C (96°F), while the average hovers around 27°C (80°F), with nighttime lows dropping to a comfortable 21°C (70°F). This month witnesses an impressive precipitation total of 295 mm (11.6 in) over approximately 22 rainy days, creating a vibrant, green landscape. The high humidity, averaging 87%, contributes to the tropical atmosphere, making September a quintessential reflection of Khe Sanh's rich natural environment.
As September unfolds in Khe Sanh, Vietnam, the weather offers a pleasing transition, with minimum temperatures averaging around 21°C (70°F) and maximums peaking at 35°C (96°F). This month's average temperature of 27°C (80°F) reflects a slight dip from the often sweltering summer months, yet it maintains a comfortable warmth that's inviting for outdoor exploration. The gradual cooling trend signals the forthcoming change of seasons, making September a delightful time to experience the rich landscapes and vibrant culture of this historical locale. While humidity levels remain, September’s relatively moderate conditions create an enjoyable atmosphere for visitors seeking both adventure and respite.
September marks a dramatic peak in precipitation for Khe Sanh, Vietnam, as the region receives 295 mm (11.6 in) of rain over 22 days. This surge is notably higher than the preceding months, reflecting the transition into the region’s wettest season. The rainfall in September not only outpaces the preceding months, such as July and August, which recorded 236 mm (9.3 in) and 162 mm (6.4 in) respectively, but also sets the stage for an even heavier downpour in October. As the landscape transforms under the weight of monsoonal rains, the increase in precipitation not only shapes local ecology but also influences daily life, making September a month of vibrant change in Khe Sanh.
In Khe Sanh, Vietnam, September marks a shift in the humidity landscape, with levels reaching 87%—a slight decrease from the peak of 92% observed in August but still notably high. As summer gives way to autumn, the air remains thick with moisture, reflecting a significant trend throughout the year. Notably, the months of July and August see the highest humidity values, often exceeding 90%, which indicates the peak of the rainy season. Following September, there is a gradual decline in humidity as the year progresses, with October and November experiencing slightly lower figures at 85% and 84%, respectively. Overall, the region's humidity remains consistently high across most of the year, particularly during the summer months, showcasing Khe Sanh’s tropical climate and the influence of monsoon patterns.
In September, Khe Sanh experiences a UV Index of 13, categorized as extreme, with a burn time of just 10 minutes. This month continues the trend observed from the peak summer months of July and August when the UV Index reached 14. Overall, from January through September, the prevailing UV Index is predominantly in the extreme range, with only a few months dipping into the very high category. It's worth noting that as the season transitions into October, the UV Index decreases slightly to 12. Therefore, if you're planning outdoor activities during this time, ensure you're equipped with adequate sun protection to mitigate the risks associated with high UV exposure. For more detailed information, visit Khe Sanh UV Index.
UV Risk Categories
As September unfolds in Khe Sanh, Vietnam, the region enjoys a delightful 289 hours of sunshine, contributing to a string of months characterized by abundant brightness. Following the peak of 315 hours in May, the sunshine gradually tapers but remains generous through the summer, with 302 hours in both July and August. This consistent warmth and light set the stage for the approaching autumn, as daylight reduces further in October to 250 hours. Overall, the trend highlights a vibrant summer followed by a gentle decline, allowing the natural beauty of Khe Sanh to shine while paving the way for the cooler, comforting months ahead.
When considering the likelihood of sunny weather in Khe Sanh, Vietnam, September presents a modest challenge for sun-seekers. With only a 15% chance of sunshine, it mirrors the low probabilities seen in the peak of the rainy season, particularly August. This period follows a string of slightly more favorable months, like May, which boasts a 42% chance of beautiful weather. As the year progresses into autumn, the chances of sunny days dwindle further, with October and November dropping to 9% and 11% respectively. Therefore, while September may not be the sunniest month, it does offer a transition towards the cooler, rainier end of the year.
In Khe Sanh, Vietnam, the daylight duration experiences a subtle yet distinct rhythm throughout the year. Beginning with consistent 11 hours of daylight in both January and February, the days gradually lengthen to 12 hours from March through August, reflecting the approach of the warmer months. By September, daylight remains steady at 12 hours, maintaining this balance before tapering off again in October to 11 hours. This pattern of slight fluctuations emphasizes a relatively stable climate, with longer days peaking in mid-year, creating an ideal backdrop for outdoor activities and exploration. Ultimately, Khe Sanh's daylight dynamics highlight a comforting predictability that residents and visitors alike can rely on throughout the changing seasons.
As the summer winds give way to the arrival of autumn, September in Khe Sanh, Vietnam, witnesses a notable decline in average wind speed, dropping to a gentle 1.7 m/s (4 mph). This marks the calmest period of the year, following a more dynamic summer where winds peaked at 4.5 m/s (10 mph) in June. The shift into September is part of a broader trend, with wind speeds steadily decreasing throughout the late spring and summer months before reaching this tranquil lull. As the season progresses, the winds gradually regain strength, hinting at the changes October will bring, reflecting the cyclical nature of the region's climate.
Weather in Khe Sanh varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Khe Sanh, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present distinctly different weather patterns. September experiences a much warmer climate, with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 35°C (96°F) and an average of 27°C (80°F). The month is also characterized by high humidity at 87% and significant rainfall, totaling around 295 mm (11.6 in) over 22 days. In contrast, January offers a cooler atmosphere, with temperatures dropping to a minimum of 10°C (51°F) and reaching a maximum of 31°C (88°F), averaging 20°C (68°F). This month sees less precipitation, about 94 mm (3.7 in), over 18 days, along with a slight decrease in humidity to 77%. For more detailed information on January weather, you can check Khe Sanh weather in January.
In comparing the weather conditions of September and February, it’s clear that September experiences significantly warmer temperatures, with averages around 27°C (80°F) and highs reaching up to 35°C (96°F). In contrast, February sees cooler temperatures, with an average of 20°C (69°F) and maximums of 33°C (92°F). Additionally, September is much wetter, boasting 295 mm (11.6 in) of rainfall over 22 days, while February’s precipitation is considerably lower at 60 mm (2.4 in) over just 13 days. The humidity level also drops from a high of 87% in September to 73% in February, leading to a more comfortable ambiance during the latter month. For more detailed information, you can check Khe Sanh weather in February.
September and March exhibit distinct weather characteristics, shaping the experience of each month. In September, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), with an average of 27°C (80°F). The month is marked by high humidity at 87% and significant rainfall, totaling 295 mm (11.6 in) over 22 days. In contrast, March offers a cooler climate, with temperatures starting at a minimum of 15°C (59°F) and reaching a maximum of 36°C (97°F), averaging at 24°C (75°F). March experiences much lower precipitation of 75 mm (2.9 in) over 17 days and a more comfortable humidity level of 64%. For a detailed look at the weather conditions during this month, you can refer to Khe Sanh weather in March.
In comparing the weather of September and April, we find notable differences in temperature and precipitation patterns. September typically experiences warmer conditions, with a minimum temperature of 21°C (70°F), an average of 27°C (80°F), and a peak reaching up to 35°C (96°F). This month also sees significant rainfall, with 295 mm (11.6 in) of precipitation over 22 days and high humidity levels at 87%.
In contrast, April presents milder temperatures, with a minimum of 15°C (60°F) and an average of 25°C (78°F), while the maximum can touch 36°C (98°F). Precipitation in April is considerably lower, totaling only 105 mm (4.1 in) over 18 days, and the humidity drops to a more comfortable 60%. For more detailed insights on April weather, please visit Khe Sanh weather in April.
In comparing the weather between September and May, September tends to be more humid and wetter than May. September features a minimum temperature of 21°C (70°F) and an average of 27°C (80°F), with maximum temperatures reaching 35°C (96°F), accompanied by 295 mm (11.6 in) of precipitation over 22 days and high humidity at 87%. In contrast, May offers slightly cooler minimum temperatures at 18°C (66°F), an average of 28°C (82°F), and can reach up to 38°C (100°F). Precipitation in May is significantly lower at 136 mm (5.4 in) over 21 days, and the humidity is also more comfortable at 73%. This makes May a drier and somewhat warmer month compared to the wetter and more humid conditions of September. For more detailed information, check Khe Sanh weather in May.
In comparing the weather of September and June, we can observe some notable differences. September experiences slightly cooler temperatures, with averages around 27°C (80°F) compared to June's higher average of 29°C (84°F). Although June has a higher maximum temperature of 38°C (101°F), September's peak can reach up to 35°C (96°F). Precipitation is also significantly higher in September, with 295 mm (11.6 in) over 22 days of rain, while June sees only 64 mm (2.5 in) across 12 days. Additionally, September's humidity is higher at 87%, compared to June's 82%. For a more detailed look at June weather, you can visit Khe Sanh weather in June.
In comparing the weather between September and July, we notice that both months experience warm temperatures, but July tends to be slightly hotter with an average temperature of 28°C (82°F) compared to September's 27°C (80°F). July also records higher maximum temperatures, reaching up to 37°C (100°F), while September peaks at 35°C (96°F). However, September experiences significantly more precipitation, with 295 mm (11.6 in) falling over 22 days, compared to July's 236 mm (9.3 in) over 18 days. Humidity is high in both months, with July at 90% and September at 87%. For more details specific to July weather, you can check Khe Sanh weather in July.
In comparing the weather of September and August, we observe that September experiences slightly cooler minimum and average temperatures, with a minimum of 21°C (70°F) and an average of 27°C (80°F), compared to August's minimum of 22°C (72°F) and average of 27°C (82°F). However, September sees higher maximum temperatures reaching up to 35°C (96°F), while August hits a peak of 36°C (97°F). Precipitation increases significantly in September, totaling 295 mm (11.6 in) over 22 days, compared to August's 162 mm (6.4 in) over 21 days. Humidity is slightly lower in September at 87%, whereas August presents a more humid environment at 92%. For more specific details on August's weather, you can visit Khe Sanh weather in August.
In September, the weather is characterized by warm temperatures, with daily averages around 27°C (80°F) and highs reaching 35°C (96°F). However, this month also experiences significant rainfall, totaling 295 mm (11.6 in) over 22 days, along with high humidity at 87%. In contrast, October sees a slight decrease in average temperature to 25°C (76°F), with minimums of 19°C (66°F) and maximums of 34°C (93°F). Despite the cooler temperatures, October brings even more rainfall, accumulating 426 mm (16.8 in) over 24 days, while humidity remains relatively high at 85%. For more detailed insights, check the weather specifics for October at Khe Sanh weather in October.
September and November show notable differences in weather, with September typically warmer and more humid. In September, temperatures range from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), with an average of 27°C (80°F). This month experiences significant rainfall, totaling 295 mm (11.6 in) over 22 days, and the humidity hovers around 87%.
In contrast, November sees cooler temperatures, with a minimum of 15°C (60°F) and a maximum of 32°C (90°F), leading to a lower average of 23°C (73°F). Although November has slightly more precipitation at 318 mm (12.5 in) over 23 days, the humidity is somewhat lower at 84%. For more detailed weather information, you can refer to Khe Sanh weather in November.
In September, the weather is significantly warmer with temperatures ranging from a minimum of 21°C (70°F) to a maximum of 35°C (96°F), averaging around 27°C (80°F). The month experiences substantial rainfall, with 295 mm (11.6 in) of precipitation over 22 days, accompanied by high humidity levels at 87%. In contrast, December brings cooler temperatures, with a minimum of 14°C (57°F) and a maximum of 29°C (85°F), averaging 20°C (68°F). Rainfall decreases to 164 mm (6.5 in) over the same number of days, and humidity slightly drops to 83%. For more insight into December's climate specifics, refer to Khe Sanh weather in December.
In September, Khe Sanh's weather stands out with its distinctive characteristics, marked by high humidity and significant rainfall. This month typically experiences much wetter conditions compared to the drier months, with nearly three-quarters of the month seeing precipitation. Average temperatures hover comfortably but can peak significantly, presenting a mix of both warm and humid days. Travelers should be prepared for these variable conditions that contrast sharply with the drier, cooler months that precede and follow September. For a deeper insight into what to expect throughout the year, visit Khe Sanh Climate.