Last updated: August 31, 2025
In Siddharthanagar, Nepal, September ushers in a blend of warm temperatures and high humidity, with maximum highs reaching 35°C (96°F) and average readings around 28°C (83°F). The month is characterized by a significant amount of rainfall, accumulating to 304 mm (12.0 in) over 23 days, creating a lush and vibrant landscape. The average humidity sits at a notable 91%, contributing to the tropical feel of the region during this time. For those experiencing Siddharthanagar in September, preparing for both warmth and rain is essential.
In Siddharthanagar, Nepal, September marks a transitional phase in the climate, as temperatures begin to dip slightly from the summer highs. The month features a minimum temperature of 23°C (73°F), an average of 28°C (83°F), and a maximum of 35°C (96°F). This notable drop from August's steady warmth suggests a subtle shift towards the cooler autumn months that are ahead. Despite the lingering heat, especially during the day, the evenings offer a pleasant respite, setting the stage for more comfortable weather in October. Overall, September serves as a bridge, blending the vibrant energy of summer with the refreshing calm of fall in this picturesque region.
In September, Siddharthanagar experiences a significant transition in precipitation patterns, receiving 304 mm (12.0 in) of rain over 23 days. This marked decrease from the intense monsoon months of July and August highlights the tail-end of the rainy season, as the region gradually shifts towards drier conditions. Notably, September maintains a robust level of rainfall compared to the earlier months of the year, reinforcing its position as one of the wetter months. As the rain dwindles in October to just 39 mm (1.5 in) over 7 days, it becomes clear that Siddharthanagar is entering a period of reprieve from the heavy monsoon deluges, setting the stage for a drier autumn.
In September, Siddharthanagar experiences one of its most humid months, with an impressive humidity level of 91%, reflecting a trend that begins in late summer and continues into the fall. This spike follows the peak levels of July and August, where humidity reaches 90% and 91% respectively. As the monsoon season wanes, this elevated moisture often lingers in the air, making the environment feel heavy and dense. However, this high humidity starts to gradually decline as October approaches, dropping to 86%, signaling the transition towards drier months ahead. The overall pattern from early in the year demonstrates a shifting cycle from drier winter months, such as January at 65%, to the lush, humid conditions of late summer and early autumn, ultimately leading back into the relatively moderate humidity of winter.
In September, Siddharthanagar experiences an UV Index of 11, categorized as extreme, with a burn time of just 10 minutes. This trend follows the intense conditions seen through the summer months, as the UV Index has remained high since May, peaking at 13 in July. As the monsoon wanes, the persistent extreme levels remind residents and visitors alike to stay vigilant about sun protection. Notably, after September, the UV Index begins to drop, returning to very high levels in October, making it essential to remain mindful of sun exposure. For more information on UV conditions throughout the year, visit Siddharthanagar UV Index.
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As the vibrant hues of September unfold in Siddharthanagar, the city basks in a welcoming 292 hours of sunshine, a delightful balance following the warmer summer months. This increase in daylight sets the tone for a gentle transition into autumn, continuing the trend of consistently abundant sunlight seen throughout the year, particularly from March through May when the hours peak. Though September experiences a slight dip compared to the sunniest months, it still radiates a warmth that is more than enough to invigorate the spirit. As the skies begin to clear after the monsoon, the city's charm shines even brighter, inviting locals and visitors alike to enjoy the mild, sun-kissed days. With October promising 320 hours of sunshine, the golden days ahead offer a perfect backdrop for exploration and celebration in this beautiful part of Nepal.
In Siddharthanagar, Nepal, September tends to be a transitional month in terms of weather, with a 30% chance of sunny days. This marks a notable decline after the sunniest months of the year, with February and March boasting an impressive 85% likelihood of clear skies. As the monsoon season approaches its end in early September, sunny days become increasingly scarce, reflecting a sharp drop from August's mere 8%. After September, the likelihood of sunshine begins to rebound, with October and November returning to more favorable conditions at 70%. Overall, while September offers a glimpse of sun amidst the lingering monsoon, it is advisable to prepare for some cloud cover and rain.
In Siddharthanagar, Nepal, September marks a gentle transition as the daylight duration begins to wane, offering 12 hours of light. This signals a shift from the peak summer days of May through August, where the sun generously lit the skies for 13 hours a day. Interestingly, September still holds onto a significant amount of daylight, reflecting a gradual decrease rather than an abrupt shift. Following this month, October will see a further reduction to 11 hours, as the region prepares for the shorter days of winter. This rhythmic pattern of daylight highlights the region's picturesque seasonal changes, inviting both reflection and appreciation of nature's cycles.
In Siddharthanagar, Nepal, September ushers in a subtle shift in the average wind speed, revealing a gentle yet invigorating breeze at around 2.0 m/s (5 mph). This marks a stable moment following the more varied winds of the summer months, fostering a pleasant environment as the monsoon fades. Compared to the preceding months—where August saw a slight dip to 1.8 m/s (4 mph)—September maintains this moderate pace, reflecting a trend toward stability as the region transitions into autumn. This gentle wind serves not only as a refreshing change but also enhances the vibrant atmosphere of the area, making it a delightful time for outdoor activities and enjoying nature's beauty.
Weather in Siddharthanagar varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Siddharthanagar, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present starkly contrasting weather conditions. In September, temperatures soar with a minimum of 23°C (73°F) and an average of 28°C (83°F), reaching a maximum of 35°C (96°F). The month is characterized by high humidity at 91% and significant precipitation, with 304 mm (12.0 in) falling over 23 days. In contrast, January experiences much cooler weather, with temperatures dipping to a minimum of 4°C (40°F) and averaging around 14°C (58°F), peaking at 28°C (82°F). Additionally, January sees much less rainfall, accumulating only 20 mm (0.8 in) over just 2 days, and lower humidity at 65%. For more details about the January weather, you can visit Siddharthanagar weather in January.
September and February present contrasting weather conditions. In September, temperatures are noticeably higher, with a minimum of 23°C (73°F) and an average of 28°C (83°F), peaking at 35°C (96°F). This month also experiences significant rainfall, totaling 304 mm (12.0 in) over 23 days, accompanied by high humidity at 91%. In stark contrast, February offers a much cooler climate, featuring a minimum temperature of 7°C (45°F) and an average of 18°C (64°F), with maximums reaching 31°C (89°F). Precipitation is minimal during this month, with only 17 mm (0.7 in) over just 2 days and a lower humidity of 55%. These differences make September feel hot and wet, while February is characterized by cooler, drier conditions. For more detailed information on February weather, check Siddharthanagar weather in February.
September and March present contrasting weather conditions. In September, temperatures range from a minimum of 23°C (73°F) to a maximum of 35°C (96°F), with an average of 28°C (83°F). The month is characterized by high humidity at 91% and significant rainfall, totaling 304 mm (12.0 in) across 23 days. In stark contrast, March experiences a cooler climate with temperatures ranging from a low of 9°C (48°F) to a high of 36°C (97°F), averaging around 23°C (74°F). Precipitation in March is minimal, with only 13 mm (0.5 in) over 3 days and much lower humidity at 39%. For more detailed weather information, you can check Siddharthanagar weather in March.
September and April present contrasting weather conditions. In September, average temperatures are warm, ranging from a minimum of 23°C (73°F) to a maximum of 35°C (96°F), accompanied by heavy rainfall totaling 304 mm (12.0 in) over 23 days and high humidity levels at 91%. In contrast, April offers a wider temperature range with a minimum of 16°C (60°F) and a striking maximum of 40°C (104°F), but significantly less precipitation at just 25 mm (1.0 in) over 6 days and much lower humidity at 24%. This makes the two months markedly different in terms of comfort and weather patterns. For more details on April’s climate specifics, visit Siddharthanagar weather in April.
When comparing the weather in September and May, notable differences emerge. September typically features higher humidity levels at 91%, with average temperatures ranging from a warm 28°C (83°F) to a peak of 35°C (96°F). This month is also characterized by substantial rainfall, receiving 304 mm (12.0 in) over 23 days. In contrast, May presents a warmer climate with maximum temperatures soaring to 41°C (106°F), though it starts slightly cooler with minimum temperatures around 18°C (65°F). Additionally, May experiences significantly less rain, totaling 113 mm (4.4 in) over only 11 days, and the humidity drops to a more comfortable 36%. For more details on the weather in May, you can visit Siddharthanagar weather in May.
September and June display distinct weather patterns that highlight the transition from summer to autumn. In September, temperatures range from a minimum of 23°C (73°F) to a maximum of 35°C (96°F), with an average of 28°C (83°F). However, this month experiences considerable rainfall, with about 304 mm (12.0 in) of precipitation spread over 23 days, leading to high humidity levels at 91%. In contrast, June typically has higher average temperatures, with a range of 23°C (73°F) to 42°C (107°F) and an average of 30°C (86°F). June’s rainfall is slightly less at 256 mm (10.1 in) over 20 days, accompanied by lower humidity levels at 65%. For more detailed information about the weather in June, you can check Siddharthanagar weather in June.
In comparing the weather between September and July, we observe some notable differences. September typically features a minimum temperature of 23°C (73°F) and an average of 28°C (83°F), with a maximum reaching 35°C (96°F). In contrast, July is slightly warmer, with temperatures ranging from a minimum of 24°C (76°F) to an average of 29°C (84°F), and a peak of 37°C (99°F).
Precipitation presents a more pronounced contrast; September records 304 mm (12.0 in) across 23 days, while July sees a much heftier 514 mm (20.2 in) over 28 days, indicating that July is generally wetter. Humidity levels remain high in both months, with September at 91% and July at 90%, creating a humid atmosphere throughout. For more detailed insights, check out Siddharthanagar weather in July.
In comparing the weather of September and August, September experiences slightly cooler temperatures, with a minimum of 23°C (73°F) and an average of 28°C (83°F), compared to August's minimum of 24°C (76°F) and average of 29°C (84°F). However, September sees a significant drop in maximum temperature, peaking at 35°C (96°F) compared to August's higher maximum of 37°C (98°F). Precipitation levels also decrease in September, totaling 304 mm (12.0 in) over 23 days, whereas August receives more rainfall at 409 mm (16.1 in) across 29 days. Humidity remains consistent in both months at 91%. For more details on August's weather, you can check Siddharthanagar weather in August.
September weather in Siddharthanagar is characterized by higher temperatures and significantly more precipitation compared to October. With minimum temperatures around 23°C (73°F) and an average of 28°C (83°F), September experiences frequent rain, totaling 304 mm (12.0 in) over 23 days and a humidity level of 91%. In contrast, October sees a drop in minimum temperatures to 15°C (59°F) and an average temperature of 26°C (79°F), accompanied by a much lighter precipitation of 39 mm (1.5 in) over just 7 days, and a slightly lower humidity of 86%. For more details on the October weather specifics, you can check Siddharthanagar weather in October.
September and November present contrasting weather patterns. In September, temperatures soar with a minimum of 23°C (73°F) and can reach highs of 35°C (96°F), accompanied by significant rainfall of 304 mm (12.0 in) over 23 days, resulting in high humidity at 91%. In stark contrast, November experiences much cooler temperatures, with a minimum of 11°C (52°F) and an average of 21°C (69°F), peaking at 33°C (92°F). The month is remarkably dry, receiving only 2 mm (0.1 in) of precipitation across zero rainy days, and the humidity drops to 79%. To learn more about the weather specifics for November, you can visit Siddharthanagar weather in November.
September and December present contrasting weather conditions. In September, the temperatures are significantly warmer, ranging from a minimum of 23°C (73°F) to a peak of 35°C (96°F), with an average of 28°C (83°F). This month is also characterized by high humidity at 91% and substantial rainfall, totaling 304 mm (12.0 in) over 23 days. In stark contrast, December offers much cooler weather, with temperatures dropping to a minimum of 5°C (42°F) and an average of 16°C (61°F), peaking at 28°C (83°F). Precipitation is minimal during this month, with only 10 mm (0.4 in) falling on just 1 day, and humidity decreases to 75%. For more details on December’s weather in Siddharthanagar, you can visit Siddharthanagar weather in December.
As September unfolds in Siddharthanagar, the weather marks a distinct shift from the drier months preceding it. With an average temperature that hovers around a warm 28°C (83°F), the days can still feel quite hot, peaking at 35°C (96°F), yet the evenings bring a refreshing coolness. This month is characterized by substantial humidity levels, reaching 91%, contributing to a muggy atmosphere. Additionally, the region experiences significant rainfall, with 304 mm over 23 days, transforming the landscape into a vibrant tapestry of greenery. Such conditions contrast sharply with the hotter and drier summer months, making September a unique time to experience the full richness of Siddharthanagar's climate. For further details, explore Siddharthanagar Climate.