Last updated: August 21, 2025
September in Chennai, India marks the transition from the sweltering summer to more humid conditions, with maximum temperatures reaching 34°C (93°F) and an average of 29°C (84°F). Despite the lingering warmth, the minimum temperature dips to a comfortable 25°C (77°F). This month also brings significant rainfall, totaling 126 mm (5.0 in) over 19 days, making it one of the wetter times of the year. With an humidity level averaging 81%, the air becomes thick and heavy, creating a quintessentially tropical experience that locals and visitors can’t ignore.
In September, Chennai experiences a delightful transition as the city begins to cool slightly from the sweltering summer months. The minimum temperature hovers around a comfortable 25°C (77°F), while average temperatures settle at a pleasant 29°C (84°F), peaking at a maximum of 34°C (93°F). This month marks a subtle shift, leading from the intense heat of May and June, where temperatures frequently reached up to 38°C (100°F), towards the more moderate conditions of October. As the monsoon season approaches, September offers a refreshing respite, making it an ideal time to explore the bustling city and enjoy its vibrant culture amidst the warm yet increasingly tolerable climate.
September marks a significant turning point in precipitation for Chennai, India, as the monsoon intensifies. With an average precipitation of 126 mm (5.0 in) spread over 19 days, this month typically ushers in the final waves of the rainy season. The rainfall in September closely follows August's substantial total of 125 mm (4.9 in), reflecting a peak in monsoon activity before the onset of October's even heavier downpour, which averages 169 mm (6.7 in). As days grow rainier, the city experiences a lush transformation, highlighting September's role as a vital month in Chennai's climatic rhythm.
In September, Chennai experiences a humidity level of 81%, which is consistent with the prevalent trend observed in the preceding summer months. As the city transitions from the sweltering heat of April and May, where humidity peaks at 83%, the levels begin to stabilize during the rainy season. August's humidity of 82% slightly tapers off in September, before dipping in October to 79%. This subtle decline signals the easing of the intense monsoon atmosphere that characterizes the preceding months, reflecting Chennai’s cyclical climatic patterns. Overall, September’s humidity contributes to the tropical feel of the city, making it an integral part of Chennai's weather narrative.
In September, Chennai experiences a UV Index of 13, categorizing the exposure as extreme and necessitating a cautious approach to sun exposure, with a burn time of just 10 minutes. This trend of high UV levels continues from the previous months of July and August, which also recorded a UV Index of 13. The consistency of extreme UV ratings throughout the summer months highlights the importance of sun protection, as residents should remain vigilant against harmful UV rays. As the year progresses into October, there’s a slight decline to an index of 11; however, the risk remains significant. For more insights, you can explore the detailed UV Index data for the region at Chennai UV Index.
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As September unfolds in Chennai, the city basks in approximately 293 hours of sunshine, reflecting a gentle decline from the summer peak experienced in previous months. While January kicks off the year with 264 hours of bright days, a steady increase throughout the spring and summer culminates in sun-drenched May, boasting 352 hours. The warmth tapers off slightly as the monsoon season approaches, culminating in September's inviting glow that still offers plenty of sunlight. Despite the slight drop from the vibrant summer months, this late-summer sunshine continues to herald the onset of the changing seasons, providing a warm embrace before the cooler days of autumn settle in.
In Chennai, India, September is notably one of the least sunny months of the year, with only a 13% chance of sun. This trend highlights a sharp decline in clear skies as the monsoon season reaches its peak, following the more favorable weather of the earlier months. For context, February and March enjoy a much brighter 70% and 69% chance of sunshine respectively, while the sunny optimism wanes as one approaches the heavy monsoon months. By September, the city often experiences overcast conditions and substantial rainfall, making it a time when sun-seekers might reconsider their plans. As the year progresses, the odds slowly improve again, but for those hoping for vibrant sunny days, September's gloomy forecast can be quite a letdown.
As September rolls into Chennai, India, the city basks in 12 hours of daylight, continuing the steady trend from the previous months. This extended period of daylight, which started in mid-March, showcases a peak towards the summer months, lasting through the monsoon season. While January and February welcome shorter days at 11 hours, the hours gradually increase and stabilize from March to August, celebrating the abundant sunlight that characterizes this tropical region. As the year progresses into October, daylight begins to wane again, returning to 11 hours. This rhythm of light and shadow contributes to Chennai's vibrant atmosphere, marking the changing seasons with a consistent embrace of daylight.
As September arrives in Chennai, the city's winds settle into a consistent rhythm, averaging 3.5 m/s (8 mph). This marks a return to the moderate breeziness experienced earlier in the year, reminiscent of April and August. Following the heightened gusts of summer, where May and June witnessed slightly stronger winds peaking at 4.1 m/s and 4.2 m/s respectively, September feels like a gentle embrace that balances comfort with a hint of tropical fervor. The steady wind speed not only contributes to the vibrant coastal atmosphere but also signals the gradual transition towards the cooler months ahead, as October dips slightly to 2.8 m/s. Embracing this month means savoring the calming breezes that dance through Chennai’s bustling streets and serene shoreline alike.
Weather in Chennai varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Chennai, focusing on differences in temperature, rainfall, humidity, and UV levels.
In September, the weather is significantly warmer and more humid compared to January, with temperatures ranging from a minimum of 25°C (77°F) to a maximum of 34°C (93°F) and an average of 29°C (84°F). Additionally, September sees a considerable amount of rainfall, totaling 126 mm (5.0 in) over 19 days, contributing to a high humidity level of 81%. In contrast, January experiences milder temperatures, with a minimum of 20°C (68°F) and a maximum of 30°C (86°F), averaging at 25°C (78°F). January is also much drier, with only 32 mm (1.3 in) of precipitation spread over just 5 days, and a slightly lower humidity of 76%. For more details, visit Chennai weather in January.
In September, the weather is notably warmer, with minimum temperatures around 25°C (77°F) and averages reaching up to 29°C (84°F), while maximum temperatures can climb to 34°C (93°F). This month also sees considerable rainfall, with 126 mm (5.0 in) distributed over 19 days, resulting in high humidity levels of 81%. In contrast, February offers a milder climate, with minimum temperatures at 20°C (68°F) and averages around 26°C (79°F), peaking at 31°C (88°F). The month is considerably drier, receiving only 10 mm (0.4 in) of precipitation over just 1 day, and featuring lower humidity at 76%. For more details, you can refer to this link: Chennai weather in February.
When comparing the weather in September and March, we see notable differences in temperature and precipitation. September typically has a higher average temperature, ranging from a minimum of 25°C (77°F) to a maximum of 34°C (93°F), while March offers slightly cooler conditions, with temperatures ranging from 22°C (72°F) to 35°C (95°F). Precipitation in September is significantly higher, with about 126 mm (5.0 in) falling over 19 days, contrasting sharply with March's mere 6 mm (0.2 in) of rain, which occurs on just 1 day. Despite both months having a humidity level of 81%, the wet and humid conditions of September make it feel more oppressive compared to the drier and slightly more pleasant weather typically experienced in March. For a detailed outlook on March weather, you can visit Chennai weather in March.
When comparing the weather of September and April, both months feature warm temperatures; however, April tends to be slightly hotter on average. In April, temperatures range from a minimum of 25°C to a maximum of 35°C (96°F), with an average of 30°C (86°F). In contrast, September sees temperatures ranging from 25°C to 34°C (93°F), with an average of 29°C (84°F). A significant difference between the two months lies in precipitation: September experiences 126 mm (5.0 in) over 19 days, while April enjoys a much drier climate, with only 8 mm (0.3 in) over just 1 day. Humidity levels are somewhat similar, with September at 81% and April slightly higher at 83%. For more details about April weather, check out Chennai weather in April.
September and May present distinct weather characteristics in terms of temperature, precipitation, and humidity. September experiences milder temperatures with a minimum of 25°C (77°F) and an average of 29°C (84°F), while May offers a higher average temperature of 31°C (88°F) and peaks at a maximum of 38°C (100°F). Rainfall is considerably more frequent in September, with 126 mm (5.0 in) spread over 19 days, compared to the scant 13 mm (0.5 in) over just 3 days in May. Humidity levels remain relatively similar, with September at 81% and May slightly higher at 83%. For more detailed insights, check out Chennai weather in May.
In comparing the weather between September and June, we notice some distinct differences despite both months experiencing high humidity levels of 81%. September sees a slightly milder average temperature of 29°C (84°F) compared to June's 31°C (88°F) and also has a lower maximum temperature of 34°C (93°F) versus June's peak of 37°C (99°F). Rainfall is significantly higher in September, with 126 mm (5.0 in) over 19 days, contrasting with June's 64 mm (2.5 in) over just 12 days. This makes September a wetter month, while June tends to be hotter and drier. For more details, you can refer to Chennai weather in June.
In comparing the weather of September and July, we see some notable differences. September tends to be slightly cooler, with average temperatures ranging from a minimum of 25°C (77°F) to a maximum of 34°C (93°F), while July's temperatures are a bit higher, peaking at 36°C (97°F) with an average of 30°C (86°F). Rainfall is more prevalent in September, receiving 126 mm (5.0 in) over 19 days compared to July's 107 mm (4.2 in) over 16 days. Humidity levels are quite similar, with September at 81% and July at 80%, making both months feel quite muggy. For a more detailed look at the conditions during this period, you can check out Chennai weather in July.
In comparing September and August weather, both months exhibit similar temperature ranges, with September showing a slight decrease in minimum temperature at 25°C (77°F), compared to August's 26°C (79°F). The average temperatures remain quite close, with September at 29°C (84°F) and August at 29°C (85°F). However, September experiences a slightly cooler maximum temperature of 34°C (93°F) compared to August's peak of 35°C (95°F). Precipitation levels are nearly identical, with September receiving 126 mm (5.0 in) and August almost the same at 125 mm (4.9 in), both spread over 19 days. Humidity levels remain consistent, with September at 81% and August slightly higher at 82%. For a closer look at the conditions during the preceding month, you can check Chennai weather in August.
In September, Chennai experiences warmer temperatures with a minimum of 25°C (77°F) and an average of 29°C (84°F), peaking at 34°C (93°F). The month sees significant rainfall, totaling 126 mm (5.0 in) across 19 days, along with high humidity levels at 81%. As October rolls in, temperatures slightly decrease, with a minimum of 24°C (76°F) and an average of 28°C (83°F), while the maximum remains steady at 33°C (93°F). However, precipitation increases to 169 mm (6.7 in), occurring over 21 days, and humidity slightly drops to 79%. For more detailed information, you can check Chennai weather in October.
In September, the weather in Chennai typically features warmer temperatures, with an average of 29°C (84°F) and maximums reaching up to 34°C (93°F). The month experiences considerable rainfall, accumulating around 126 mm (5.0 in) over 19 days, along with high humidity levels at 81%. In contrast, November sees slightly cooler temperatures, averaging 27°C (81°F) with maximums of 32°C (90°F). However, the precipitation significantly increases to 377 mm (14.9 in) over 20 days, with humidity remaining similar at around 80%. For a more detailed look at the weather patterns, you can check out Chennai weather in November.
In September, the weather is warmer with average temperatures reaching 29°C (84°F) and maximum highs of 34°C (93°F), while December sees a more moderate average of 26°C (79°F) and a maximum of 30°C (87°F). September experiences greater humidity at 81% and substantial rainfall, totaling 126 mm (5.0 in) across 19 days. In contrast, December is drier with only 109 mm (4.3 in) of precipitation over 10 days and slightly lower humidity at 78%. For more detailed information on December weather, check out Chennai weather in December.
As September arrives in Chennai, the weather undergoes a notable transformation, marked by a blend of warmth and heightened humidity. With average temperatures lingering around a comfortable 29°C, this month sees increased cloud cover and substantial rainfall, delivering approximately 126 mm over 19 days. Compared to the previous months, September is particularly characterized by its frequent showers, which offer a respite from the summer heat but also raise humidity levels to a muggy 81%. This unique combination makes the air feel heavier, creating a distinct atmosphere as the city transitions from the dry spells of summer to the rejuvenating influence of the monsoon. For more insights into Chennai's climate, visit Chennai Climate.