Last updated: August 21, 2025
September in Phnom Penh, Cambodia showcases a tropical climate marked by high temperatures and significant rainfall. With a maximum temperature reaching 36°C (97°F) and an average of 28°C (83°F), the month offers warm days, while nighttime lows hover around a comfortable 24°C (76°F). However, the wet season is in full swing, bringing 246 mm (9.7 in) of precipitation over an average of 26 days, coupled with a high humidity level of 87%. Visitors and residents alike should brace for a mix of sunshine and frequent showers, making this a vibrant yet challenging time of year in the capital.
In September, Phnom Penh experiences a warm and inviting climate, with temperatures ranging from a pleasant 24°C (76°F) at night to a maximum of 36°C (97°F) during the daytime. The average temperature hovers around 28°C (83°F), indicating a slight dip from the peak heat of the preceding months. This transition marks the end of the intense summer heat, as the city begins to cool down slightly, preparing for the upcoming rainy season. Overall, September's temperatures reflect a balance between warmth and comfort, making it an ideal time for visitors to explore the vibrant culture and rich history of Cambodia's capital.
September marks a significant peak in precipitation for Phnom Penh, with 246 mm (9.7 in) of rainfall over 26 days. This deluge continues the trend established in the preceding months, where heavy rains consistently dampen the city, particularly in June, July, and August, which also see substantial rainfall. The monsoon season truly takes hold by September, making it one of the wettest months of the year. With nearly every day of the month bringing rain, the lush landscapes and vibrant greenery of the city thrive, showcasing the beauty and challenges of tropical weather patterns. As the rain pours, residents must navigate both the refreshing and disruptive aspects of this dynamic climate.
September in Phnom Penh, Cambodia, is characterized by high humidity, registering at 87%. This marks a slight decrease from the previous month, August, which peaked at 88%. The trend throughout the rainy season showcases a steady rise in humidity, starting from a moderate 62% in January, gradually climbing as the months progress, culminating in the sultry conditions of July and August. As the city transitions into October, humidity levels remain relatively high but begin to decline, hinting at the gradual easing of the monsoon season. Overall, September encapsulates a month of thick, tropical air that reflects the city's vibrant wet-season atmosphere.
In September, Phnom Penh experiences a UV Index of 14, categorizing it as extreme with a burn time of just 10 minutes. This month continues the trend of high UV levels seen throughout the months preceding it, reflecting the persistent intensity of the sun in the region. From January's relatively high index of 10 to the extreme peaks in February through August, the UV exposure remains critical for residents and visitors alike, underscoring the importance of sun protection. As the season shifts, both locals and tourists should remain vigilant about safeguarding their skin against harmful UV radiation. For more information on UV levels throughout the year, check out Phnom Penh UV Index.
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September in Phnom Penh showcases a delightful blend of warmth and sunshine, boasting an impressive 261 hours of sunlight. While this marks a slight dip from the peak of 329 hours in March, it still reflects a robust and vibrant atmosphere as the rainy season begins to wane. Following the steady figures of 312 hours in both April and May, September’s sunshine continues to reinforce the city's reputation for a predominantly sun-kissed climate, making it an ideal time to explore the rich culture and history of Cambodia. As the year transitions towards October's 275 hours, the golden rays linger, inviting both locals and visitors to bask in the beauty that September offers.
September in Phnom Penh, Cambodia, marks a noticeable decline in sunny weather, with just an 8% chance of clear skies. This trend mirrors the preceding months of August and July, where sunny days are similarly scarce, plunging to a mere 9% and 15%, respectively. As the rainy season progresses, the city experiences its lowest likelihood of sunshine, contrasting sharply with the sun-drenched days of earlier months like February and March, which boast probabilities of 60% and 55%. If you're planning a trip in September, be prepared for overcast skies and potential rainfall, as the sun plays a shy role during this time of year.
In Phnom Penh, Cambodia, the daylight duration exhibits a consistent and rhythmic pattern throughout the year. Starting from January to February, residents enjoy 11 hours of daylight, a gentle introduction to the year. As spring approaches in March, the sun graces the city with an additional hour, reaching 12 hours of daylight. This trend of extended daylight continues through the warmer months of April to August, creating a vibrant atmosphere as days remain long and bright. Interestingly, September maintains this delightful 12-hour daylight, providing a seamless transition into the latter part of the year. However, as October rolls in, Phnom Penh gradually returns to 11 hours of daylight, signaling a shift towards the shorter days of November and December. This natural ebb and flow of daylight not only enhances the city's charm but also invites outdoor adventures throughout the sunny months.
As September settles over Phnom Penh, the gentle breeze brings a noticeable calm, with an average wind speed of 2.0 m/s (4 mph), making it one of the lighter months for wind. This follows a summer that saw July and August picking up speed, with gusts reaching 2.9 m/s (7 mph) and 2.5 m/s (6 mph), respectively. As the year transitions into fall, the winds shift down a notch, echoing the stillness of the season. The overall trend shows a gradual increase in wind as the year progresses, peaking in December with 3.1 m/s (7 mph), but September's gentle caress invites moments of tranquility, perfect for enjoying the sights and sounds of the vibrant city. Whether it’s a leisurely stroll by the river or sipping coffee at a bustling café, the September winds provide an inviting backdrop to the charm of Phnom Penh life.
Weather in Phnom Penh varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Phnom Penh, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather in Phnom Penh is characterized by higher humidity and significant rainfall, with temperatures ranging from a minimum of 24°C (76°F) to a maximum of 36°C (97°F). The month experiences an average temperature of 28°C (83°F) and sees precipitation on 26 days, totaling 246 mm (9.7 in) of rain, contributing to a humid atmosphere at 87%.
In contrast, January offers a more pleasant climate with lower humidity levels at 62%. The temperatures are slightly cooler, ranging from a minimum of 19°C (66°F) to a maximum of 36°C (96°F), while the average temperature is 27°C (82°F). There is significantly less precipitation, totaling only 19 mm (0.8 in) over just 3 days, making January a drier and more comfortable month. For more detailed information, you can check Phnom Penh weather in January.
In September, Phnom Penh experiences a hotter and more humid climate, with average temperatures around 28°C (83°F) and maximums reaching up to 36°C (97°F). The month is characterized by substantial rainfall, totaling 246 mm (9.7 in) over approximately 26 days, leading to a high humidity level of 87%. In contrast, February presents a more temperate weather pattern, with a similar average temperature of 28°C (83°F) but more comfortable maximums of 36°C (98°F). February sees significantly less rainfall, with only 10 mm (0.4 in) falling over just 2 days, and a lower humidity level of 61%. This makes February a drier and more pleasant month to enjoy outdoor activities. For more detailed information, you can check Phnom Penh weather in February.
In September, Phnom Penh experiences warm temperatures, with a minimum of 24°C (76°F) and an average of 28°C (83°F), peaking at 36°C (97°F). This month is also characterized by high humidity at 87% and significant rainfall, totaling 246 mm (9.7 in) over 26 days. In contrast, March offers a slightly cooler minimum temperature of 23°C (74°F), with an average of 30°C (86°F) and a higher maximum of 39°C (102°F). The weather in March is much drier, receiving only 30 mm (1.2 in) of precipitation across just 5 days and lower humidity at 61%. For more detailed information, you can check Phnom Penh weather in March.
In comparing the weather between September and April, one can observe some notable differences. September tends to be more humid, with an average temperature of 28°C (83°F) and maximum highs reaching up to 36°C (97°F), accompanied by significant rainfall of 246 mm (9.7 in) over 26 days. In contrast, April is typically hotter with average temperatures around 30°C (87°F) and max temperatures soaring to 39°C (103°F), yet it experiences much less precipitation at 78 mm (3.1 in) over just 14 days and a lower humidity level of 67%. For more specific details on the weather in April, visit Phnom Penh weather in April.
September and May present contrasting weather patterns in Phnom Penh. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 36°C (97°F), with an average of 28°C (83°F). This month experiences significant rainfall, with 246 mm (9.7 in) spread over 26 days, contributing to high humidity levels at 87%. In contrast, May typically sees a more intense heat, with temperatures ranging from 24°C (76°F) to a sweltering 40°C (104°F) and an average of 30°C (86°F). The precipitation during May is lower, at 155 mm (6.1 in) over 23 days, and the humidity is slightly lower at 78%. For a detailed overview of weather conditions in May, visit Phnom Penh weather in May.
When comparing the weather in September and June, it is evident that both months experience high temperatures and humidity. September has a minimum temperature of 24°C (76°F) and averages 28°C (83°F), while June exhibits a slightly higher minimum of 25°C (77°F) and an average of 29°C (85°F). The maximum temperatures are comparable, with September peaking at 36°C (97°F) and June reaching 37°C (99°F). In terms of precipitation, September is much wetter, receiving 246 mm (9.7 in) over 26 days compared to June's 155 mm (6.1 in) over 24 days. Humidity levels are slightly higher in September at 87%, compared to June's 84%. For more detailed information, you can explore Phnom Penh weather in June.
When comparing the weather in September and July, we can see notable differences. September tends to be slightly cooler, with an average temperature of 28°C (83°F) compared to July's average of 29°C (84°F). However, July experiences a higher maximum temperature of 38°C (100°F) versus September’s peak of 36°C (97°F). Both months see substantial precipitation, but September records a heavier rainfall of 246 mm (9.7 in) over 26 days, compared to July's 154 mm (6.1 in) over 25 days. Humidity levels are comparable, with September at 87% and July at 86%. For a deeper look at July's weather specifics, visit Phnom Penh weather in July.
In comparing the weather of September and August, both months showcase high temperatures and significant humidity, but there are some notable differences. September features a slightly lower minimum temperature of 24°C (76°F) compared to August's 25°C (77°F) and an average temperature of 28°C (83°F), which is just 1°C cooler than August's average of 29°C (84°F). While both months have a maximum temperature reaching 36°C (97°F), September experiences more rainfall with 246 mm (9.7 in) over 26 days, compared to August’s 197 mm (7.7 in) over the same number of days. The humidity level remains high in both months, with September at 87% and August at 88%. For more details on August's weather, you can visit Phnom Penh weather in August.
In September, the weather is characterized by slightly warmer temperatures, with a minimum of 24°C (76°F) and a maximum of 36°C (97°F), while October sees a slight decrease in maximum temperatures to 35°C (95°F) but maintains a similar average of 28°C (83°F). Both months experience significant rainfall, with September having precipitation of 246 mm (9.7 in) over 26 days, and October mirroring this total but over just 24 days. Humidity levels remain high in both months, at 87% in September and decreasing slightly to 84% in October. For more detailed information, check out Phnom Penh weather in October.
September and November present a notable contrast in weather, despite both being warm months. In September, temperatures range from a minimum of 24°C (76°F) to a maximum of 36°C (97°F), with an average of 28°C (83°F). The month is characterized by significant rainfall, amounting to 246 mm (9.7 in) over 26 days, accompanied by high humidity levels at 87%. In contrast, November features a slightly lower temperature range, with a minimum of 22°C (71°F) and a maximum of 35°C (95°F), maintaining an average of 28°C (82°F). Rainfall decreases significantly to 121 mm (4.8 in), spread over just 15 days, while humidity also slightly declines to 84%. For more detailed information, you can visit Phnom Penh weather in November.
September and December in Phnom Penh exhibit contrasting weather patterns. September tends to be much hotter, with average temperatures peaking at 28°C (83°F) and maximums reaching up to 36°C (97°F). The month is also marked by heavy rainfall, accumulating 246 mm (9.7 in) over 26 days, coupled with high humidity levels at 87%. In contrast, December offers a more moderate climate, featuring an average temperature of 27°C (81°F) and maximums of 34°C (94°F). Precipitation drops significantly to just 40 mm (1.6 in) over 5 days, and humidity levels decrease to a more comfortable 76%. For more detailed information, you can visit Phnom Penh weather in December.
As September unfolds in Phnom Penh, the city experiences a distinct shift in weather patterns compared to other months. Humidity levels soar to a steamy 87%, contributing to the tropical feel that envelops the capital. Rainfall becomes increasingly prevalent, with nearly every day seeing precipitation, making it one of the wettest months of the year. Temperatures, while remaining warm, show a slight dip in the average compared to the sweltering dry season, providing some relief. For those navigating the vibrant streets of Phnom Penh during this postcard-perfect month, being prepared for sudden showers and embracing the lush greenery that blooms in response to the rains is essential. For more insights, check out Phnom Penh Climate.