Last updated: March 19, 2025
In September, Colombo, Sri Lanka experiences a warm and humid climate, with average temperatures hovering around 27°C (81°F). Daily maximums reach up to 30°C (86°F), while nighttime lows dip to a comfortable 25°C (77°F). This month is characterized by considerable precipitation, totaling approximately 234 mm (9.2 in) over 26 days, leading to lush greenery and vibrant landscapes. With an average humidity level of 82%, visitors should be prepared for a tropical atmosphere, making it a perfect time to explore Colombo's rich culture amidst refreshing monsoon showers.
In September, Colombo, Sri Lanka experiences warm tropical weather, with temperatures showcasing a pleasant consistency. The month starts with a minimum temperature of 25°C (77°F), rising to an average of 27°C (81°F), and peaking at 30°C (86°F). This slight dip in maximum temperatures from the hotter summer months illustrates a transitional period as Colombo shifts towards the end of the season. With daily highs hovering around the 30°C mark, September remains relatively comfortable, making it an inviting time for both locals and travelers to enjoy the city's vibrant atmosphere and scenic coastal landscapes. Overall, while the warmth persists, the mild fluctuations in temperature hint at the approaching change in monsoonal patterns.
September in Colombo, Sri Lanka, marks a significant transition in precipitation patterns, with 234 mm (9.2 in) of rainfall typically gracing the city over 26 days. This month is characterized by a noticeable increase compared to the earlier months, particularly when juxtaposed against the relatively drier months of January and February, each averaging a mere 54 mm. As the year progresses, the rainfall steadily rises, peaking in October with 347 mm (13.6 in), suggesting that September serves as a precursor to the heavier downpours of the following month. This trend highlights September's role as a pivotal month in the wet season, where the frequency and intensity of rain begin to escalate, laying the groundwork for October's dominance in precipitation.
September in Colombo, Sri Lanka, sees a notable humidity level of 82%, continuing the trend established in the preceding months of June, July, and August, which all hover around the same figure. This persistent humidity reflects the region's tropical climate, where moisture levels typically peak during the mid-year months. While January kicks off the year with a relatively lower 77%, it gradually increases before stabilizing around the 82-83% range in the latter part of the year. As we transition into October, humidity only slightly declines to 81%, maintaining the quintessential lushness characteristic of Colombo’s environment. Overall, September stands as a marker of the city’s consistent tropical ambiance, where the air is rich with moisture, enhancing the vibrant local flora and fostering a warm, inviting atmosphere.
In September, the UV Index in Colombo, Sri Lanka, maintains a high level at 14, classifying it in the extreme exposure category with a rapid burn time of just 10 minutes. This trend mirrors the previous months, showcasing a notably consistent pattern of elevated UV radiation throughout the year, particularly from January to April, where indices peak at 15. Even as the seasons transition, the UV Index remains a crucial factor, fluctuating between 13 and 14 in the following months. With such sustained levels of intensity, it's essential for residents and visitors alike to prioritize sun safety measures. For more details on the UV Index trends throughout the year, visit Colombo UV Index.
UV Risk Categories
As September rolls in, Colombo, Sri Lanka, basks in 304 hours of glorious sunshine, marking a transition towards the tail end of the wet season. The trend reveals a consistency in bright days since the year's start, with monthly sunshine peaking in March at 336 hours and gradually tapering off in the later months. Following a vibrant summer, September's sun-drenched skies reflect a captivating blend of lingering warmth and the promise of seasonal change, encouraging both locals and travelers to embrace the island's lively atmosphere before the cooler months arrive. This month offers a beautiful juxtaposition of sunny days and the anticipation of nature's shift, making it a charming time to experience the unique allure of Colombo.
In Colombo, Sri Lanka, the likelihood of basking in sunny weather takes a noticeable dip in September, where the chance of sunshine hovers around 18%. This figure continues the trend of diminishing sunlight that begins in the preceding months, with August showing even lower probabilities at just 9%. Interestingly, the pattern shifts significantly as the calendar moves toward the end of the year, with December enjoying a robust 54% chance of clear skies. Thus, while September may not be the sunniest month, it serves as a precursor to the brighter days ahead as the monsoon recedes, making the later months more inviting for those seeking sunshine in Colombo.
In September, Colombo, Sri Lanka enjoys a consistent 12 hours of daylight, maintaining the trend established in the preceding months of June through August. This steady duration reflects the tropical climate’s minimal variation in daylight throughout the year, providing ample time for outdoor activities and exploration. As the days transition into October, daylight begins to wane slightly, with hours decreasing to 11. This gradual shift marks the onset of the waning daylight months, creating a gentle reminder of nature's rhythm while residents and visitors alike embrace the vibrant beauty of Sri Lanka in late summer.
In September, Colombo experiences a gentle breath of air with an average wind speed of 4.9 m/s (11 mph), reflecting a delightful transition from the bracing winds of the previous months. This moderate breeze makes September a favorable time for outdoor activities, as it combines warmth with a refreshing touch. Following the peak winds of July and August, which recorded 5.6 m/s (13 mph) and 5.3 m/s (12 mph) respectively, September's wind speed slightly diminishes but remains fairly consistent, cool enough to enjoy the beaches while hinting at the calmness of the upcoming months. As the winds settle down in October and November, it seems that September serves as a sweet reminder of summer's liveliness, providing a perfect balance for those soaking up the vibrant atmosphere of Sri Lanka.
The weather in Colombo changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Colombo and find detailed weather information for every month.
In September, temperatures in Colombo range from a comfortable minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 27°C (81°F). However, this month sees significant rainfall, with 234 mm (9.2 in) expected over 26 days, leading to a high humidity level of 82%. In contrast, January experiences slightly lower temperatures, with a minimum of 22°C (72°F) and a maximum of 33°C (92°F), while still maintaining an average of 27°C (81°F). Rainfall drops considerably to 54 mm (2.1 in) over just 7 days, resulting in a lower humidity of 77%. For more specific details, you can check out Colombo weather in January.
September and February showcase contrasting weather patterns. In September, the temperatures range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 27°C (81°F). This month experiences significant rainfall, totaling 234 mm (9.2 in) over 26 days, accompanied by high humidity at 82%. In contrast, February offers slightly warmer temperatures, with a minimum of 22°C (73°F), an average of 28°C (82°F), and a maximum of 34°C (94°F). The precipitation drops dramatically to 54 mm (2.1 in) across just 9 days, and the humidity is lower at 73%. For more detailed weather insights, visit Colombo weather in February.
September and March exhibit distinct differences in weather patterns. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 27°C (81°F). This month is characterized by high humidity at 82% and substantial rainfall amounting to 234 mm (9.2 in) over 26 days. In contrast, March boasts slightly warmer temperatures, with a minimum of 24°C (76°F), an average of 28°C (83°F), and a peak of 33°C (92°F). Moreover, rainfall in March is significantly lower at 118 mm (4.6 in) spread over 17 days, and humidity is somewhat less, at 74%. For a detailed overview of the weather in March, you can visit Colombo weather in March.
September and April present contrasting weather patterns. In September, temperatures range from a minimum of 25°C (77°F) to a maximum of 30°C (86°F), with an average of 27°C (81°F). The month is characterized by high humidity at 82% and significant precipitation, totaling 234 mm (9.2 in) over 26 days. In contrast, April offers slightly warmer average temperatures, with minimums of 25°C (77°F) and maximums reaching 33°C (91°F), and an average of 28°C (83°F). April experiences lower precipitation, amounting to 125 mm (4.9 in) across 25 days, and a more comfortable humidity level of 74%. For more details on the weather in April, you can check Colombo weather in April.
In September, the weather in Colombo boasts a warm average temperature of 27°C (81°F) with maximums reaching 30°C (86°F), coupled with high humidity levels at 82%. However, this month is marked by significant rainfall, totaling 234 mm (9.2 in) over 26 days. In comparison, May presents a slightly warmer climate, with average temperatures of 28°C (83°F) and maximums hitting 32°C (90°F). While May is also quite humid at 76%, it typically experiences even higher rainfall, accumulating 295 mm (11.6 in) over 29 days. For more detailed information, check Colombo weather in May.
In comparing September and June weather, both months experience similar temperature ranges, with September averaging around 27°C (81°F) and June slightly warmer at 28°C (82°F). However, June tends to have a marginally higher maximum temperature of 31°C (87°F), compared to September's 30°C (86°F). Precipitation is notably higher in June as well, with 257 mm (10.1 in) falling over 28 days, whereas September sees 234 mm (9.2 in) spread across 26 days. Interestingly, both months maintain the same humidity level of 82%, making them quite humid. For a closer look at June's weather specifics, you can check out Colombo weather in June.
In September, temperatures are slightly cooler than in July, with an average of 27°C (81°F) compared to July's 28°C (82°F). Both months experience similar maximum temperatures of around 30°C (86°F in September and 87°F in July). However, September is significantly wetter, receiving 234 mm (9.2 in) of precipitation over 26 days, compared to July's 168 mm (6.6 in) during the same number of days. Despite the rainfall, the humidity remains consistent at 82% for both months, ensuring a tropical feel throughout. For more details about July weather, you can check Colombo weather in July.
September weather shows a slight increase in precipitation compared to August, with a total of 234 mm over 26 days, while August recorded 189 mm over 27 days. Both months share similar temperature averages, with minimums of 25°C (77°F) and maximums hovering around 30°C (86°F in September and 85°F in August). Humidity remains high in both months, slightly decreasing from 83% in August to 82% in September. For a detailed look at August weather patterns, you can check Colombo weather in August.
September and October exhibit similar average temperatures, with both months ranging from a minimum of 24-25°C (76-77°F) to a maximum of 30°C (86°F). However, October tends to be wetter, receiving significantly more rainfall at 347 mm (13.6 in) compared to September's 234 mm (9.2 in). Additionally, October experiences precipitation on 29 days, slightly more than September's 26 days, while humidity remains fairly consistent at around 81-82%. For more detailed information, you can check Colombo weather in October.
In September, the weather tends to be warm with average temperatures around 27°C (81°F), while daily highs can reach up to 30°C (86°F). However, it is also a month characterized by significant rainfall, with around 234 mm (9.2 in) of precipitation spread over 26 days and humidity levels averaging 82%.
On the other hand, November offers a similar average temperature of 27°C (81°F), but it can occasionally warm up to a maximum of 31°C (88°F). Precipitation is notably higher during this month, totaling about 294 mm (11.6 in) over 26 days, while humidity slightly decreases to 80%. For more details on November weather, you can visit Colombo weather in November.
In comparing the weather of September and December, September features slightly warmer temperatures with a minimum of 25°C (77°F) and a maximum of 30°C (86°F), while December sees a minimum of 23°C (73°F) and a higher maximum of 32°C (89°F). Interestingly, both months have an average temperature of 27°C (81°F). However, September experiences significantly higher precipitation with 234 mm (9.2 in) over 26 days, compared to December’s 179 mm (7.1 in) over just 17 days. Humidity levels are relatively similar, with September at 82% and December at 80%. For more detailed information, you can refer to Colombo weather in December.
As September unfolds in Colombo, the city's weather takes on a unique character compared to other months. With temperatures hovering around a warm average of 27°C, this month tends to be more humid, featuring a high level of 82% humidity that can make the air feel quite thick. Rainfall is a prominent feature during September, with about 234 mm of precipitation spread across 26 days, making it one of the wetter months in the calendar. This combination of warmth and moisture creates a tropical ambience that is distinctively different from the drier periods earlier in the year. For a deeper dive into the city's weather phenomena, explore Colombo Climate.