Last updated: August 21, 2025
September in Si'an, China is characterized by a warm climate, with maximum temperatures soaring to 36°C (98°F) and an average temperature around 25°C (77°F). As the month progresses, temperatures dip to a cooler minimum of 13°C (56°F) during the nights, providing a pleasant respite from the daytime heat. However, expect a significant 120 mm (4.7 in) of rainfall spread across approximately 12 days, contributing to a humidity level of 75% that enhances the lush landscape of this historical city. Visitors should prepare for both sunshine and showers, making it a unique time to experience the vibrant culture and stunning scenery of Si'an.
In September, Si'an, China, experiences a pleasant transition into autumn, marked by a minimum temperature of 13°C (56°F) and an average of 25°C (77°F). As summer's heat begins to wane, daytime highs peak at 36°C (98°F), still warm enough to enjoy the lingering sunshine, while the evenings offer a refreshing coolness. This month is characterized by a gradual decline in temperatures, following the peak warmth of July and August, creating an ideal climate for outdoor activities. As nature starts to transition, visitors can relish in the comfortable weather while witnessing the onset of colorful autumn leaves.
In September, Si'an experiences a significant shift in weather as the summer rains start to ease. With 120 mm of precipitation over 12 days, the month strikes a balance between the intense rains of July and August and the drier spells that follow in October and November. This moderate rainfall supports the gradual transition into autumn, allowing the landscape to flourish with rich hues. September’s precipitation, while lower than the summer peak, remains substantial enough to nourish the region's agriculture, setting the stage for a bountiful harvest.
In September, Si'an, China experiences a notable shift in humidity, dropping to 75% after the sweltering summer months where humidity peaked at 90% in July. This decline marks a refreshing transition from the high humidity levels typical of the summer, with August still holding a significant 88%. As autumn approaches, the change brings a more comfortable climate, providing a brief respite before the humidity begins to rise again slightly in October to 76%. Notably, the overall humidity trend in Si'an reflects a gradual increase through the spring and summer months, culminating in September's decline, which paves the way for the dryer fall season ahead.
In September, Si'an, China experiences a UV Index of 10, indicating a very high exposure category. This slight dip from the scorching peak of 11 seen in the summer months marks a transition toward cooler autumn days, yet sunlight remains potent, with a recommended burn time of just 15 minutes. As summer fades, the UV Index gradually decreases, yet maintaining awareness and protection against sun exposure remains crucial. Early fall in Si'an signals the need to remain vigilant, especially as the daylight hours shift, but opportunities for outdoor activities abound. For more detailed insights on daily UV levels, check out the Si'an UV Index.
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September in Si'an, China, is a radiant month, basking in 258 hours of sunshine, a delightful continuation of the summer's brilliance. As the year progresses from the peak of 300 hours in August, the sun still shines generously, even as the days grow shorter. This transition marks a subtle shift as the city moves from the sun-drenched heights of summer to the gentle warmth of autumn. The month heralds a retreat from the intense solar embrace of July and August while still providing a significant amount of daylight, ensuring that the vibrant charm of the city remains alive and inviting. With September’s sunshine bridging the gap between the zenith of summer and the cooling breeze of fall, residents can relish in the lingering warmth, setting the stage for a beautiful seasonal change.
As September unfolds in Si'an, the likelihood of sunny weather rises to an encouraging 48%, making it one of the more promising months for sunshine following the typically overcast summer. This month stands out as it transitions from the lower probabilities seen in July and June, where the chances of bright days plummet to just 17% and 23%, respectively. Interestingly, September's sunshine likelihood is slightly lower than the overall popularity of November, which peaks at 52% as autumn settles in. This trend suggests a refreshing respite from the sweltering heat of summer, inviting visitors to enjoy a mix of pleasant weather and vibrant autumn scenery. So, if you're planning a trip, September in Si'an offers a delightful balance of sun and mild temperatures!
In Si'an, China, the daylight duration exhibits a captivating rhythm throughout the year. September, with its 12 hours of daylight, marks a gentle transition from the longer days of summer. As the months progress from the vibrant 14 hours in June to September's milder offering, a noticeable decline sets in, echoing the shift towards autumn. This trend sees October and November bringing shorter days, with only 11 and 10 hours, respectively, signaling the onset of winter. The alternating pattern showcases not only the changing seasons but also invites residents to savor the lingering warmth of late summer before embracing the cosier, shorter days ahead. With each month, Si'an mirrors the natural ebb and flow of daylight, creating a unique backdrop for life and activities in this historical city.
As September rolls into Si'an, the average wind speed reaches 2.5 m/s (6 mph), reflecting a mild and refreshing breeze that sets the tone for the transitioning seasons. This month stands out as a bridge between the warm summer months and the cooler autumn days. Throughout the year, wind conditions show a subtle ebb and flow, with July experiencing the highest gusts at 2.9 m/s (7 mph), while the quietest months of June and August hover around 2.1 m/s (5 mph). Notably, September's wind speed is consistent with those of January and February, hinting at a gentle shift towards cooler weather. The overall trend emphasizes a serene yet dynamic atmosphere in Si'an, making September an ideal moment to embrace the outdoors.
Weather in Si'an varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Si'an, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather conditions. In September, temperatures range from a comfortable 13°C (56°F) at night to sweltering highs of 36°C (98°F) during the day, with an average of 25°C (77°F). The month sees significant rainfall of 120 mm (4.7 in) over about 12 days, contributing to the higher humidity level of 75%. In contrast, January experiences much colder temperatures, with lows plunging to -11°C (13°F) and daytime highs peaking at around 20°C (68°F), averaging just 5°C (41°F). Precipitation decreases to 68 mm (2.7 in) spread over 8 days, accompanied by a slightly lower humidity of 70%. For more details on typical January weather, visit Si'an weather in January.
In September, the weather typically features a warm climate with temperatures ranging from a minimum of 13°C (56°F) to a scorching maximum of 36°C (98°F), averaging around 25°C (77°F). The month is also characterized by higher humidity at 75% and considerable rainfall of 120 mm (4.7 in) over approximately 12 days. In contrast, February brings a much cooler atmosphere, with temperatures dipping as low as -8°C (18°F) and averaging only 6°C (44°F), though it can still reach a pleasant maximum of 26°C (79°F). Precipitation in February is less intense, totaling 71 mm (2.8 in) over 10 days, with humidity slightly lower at 73%. For more insights into February weather, you can check Si'an weather in February.
In comparing the weather of September and March, we take note of the significant differences in temperature and conditions. September tends to be much warmer, with an average temperature of 25°C (77°F) and highs reaching up to 36°C (98°F), whereas March is considerably cooler, averaging only 12°C (54°F) and peaking at 29°C (84°F). Precipitation levels are somewhat similar, with September receiving 120 mm (4.7 in) over 12 days and March recording 106 mm (4.2 in) over 13 days. Humidity is slightly higher in March at 82%, compared to 75% in September. For more detailed information about the weather in March, you can check Si'an weather in March.
September and April present contrasting weather experiences. In September, temperatures range from a minimum of 13°C (56°F) to a maximum of 36°C (98°F), with an average temperature of 25°C (77°F). The month also sees significant rainfall, with 120 mm (4.7 in) recorded over 12 days and humidity levels at 75%. In contrast, April offers cooler temperatures, with a range from a minimum of 2°C (35°F) to a maximum of 33°C (92°F), and an average of 17°C (62°F). Total precipitation is lower at 81 mm (3.2 in) over 8 days, accompanied by a higher humidity level of 86%. For more detailed insights into April weather, you can refer to Si'an weather in April.
September and May present contrasting weather patterns, with September experiencing warmer average temperatures and higher minimums compared to May. In September, temperatures range from a minimum of 13°C (56°F) to a maximum of 36°C (98°F), with an average of 25°C (77°F). In contrast, May has cooler minimum temperatures at 8°C (47°F), peaking at 37°C (99°F) with an average of 22°C (71°F). Both months see substantial rainfall, with September recording 120 mm (4.7 in) over 12 days and May slightly higher at 135 mm (5.3 in) over 11 days. Humidity is also greater in May at 85%, compared to 75% in September, making it feel more humid during the late spring. For more detailed insights into May weather, you can check Si'an weather in May.
September and June both feature a similar average temperature of 25°C (77°F), but the overall weather patterns diverge significantly. In September, temperatures range from a minimum of 13°C (56°F) to a maximum of 36°C (98°F), while June experiences slightly warmer temperatures, with a minimum of 14°C (58°F) and a maximum of 37°C (99°F). June is also markedly wetter, receiving 257 mm (10.1 in) of precipitation over 15 days, compared to September's 120 mm (4.7 in) over 12 days. Additionally, humidity is higher in June at 85%, compared to September's 75%. For more detailed information, you can check Si'an weather in June.
When comparing the weather in September and July, a notable difference can be observed in temperature and precipitation patterns. September experiences a minimum temperature of 13°C (56°F) and an average of 25°C (77°F), while July starts at a warmer minimum of 20°C (68°F) and averages 28°C (83°F). July also sees higher maximum temperatures, reaching up to 39°C (102°F), compared to September's maximum of 36°C (98°F). Precipitation is significantly greater in July, with 299 mm (11.8 in) over 17 days, compared to September's 120 mm (4.7 in) over 12 days. Additionally, humidity levels are higher in July at 90%, contrasted with 75% in September. For more detailed information on the weather during this time, check out Si'an weather in July.
In comparison to August, September experiences slightly cooler temperatures, with a minimum of 13°C (56°F) and an average of 25°C (77°F), whereas August boasts a minimum of 18°C (64°F) and an average of 29°C (84°F). The maximum temperatures also drop from 38°C (100°F) in August to 36°C (98°F) in September. Precipitation decreases in September to 120 mm (4.7 in) over 12 days, compared to the higher 190 mm (7.5 in) over 15 days in August. Additionally, September's humidity is lower at 75%, while August remains quite humid at 88%. For more details on August weather, visit Si'an weather in August.
September and October showcase a noticeable shift in weather patterns. In September, temperatures are warmer, with averages reaching 25°C (77°F) and highs of up to 36°C (98°F). However, it also experiences significant precipitation, totaling 120 mm (4.7 in) over 12 days. In contrast, October sees cooler temperatures, with an average of 19°C (66°F) and a maximum of 34°C (93°F). Rainfall decreases sharply to 50 mm (2.0 in) spread over just 8 days, while humidity remains relatively stable at 76%. For more details on October weather, you can check Si'an weather in October.
September and November present a stark contrast in weather conditions. In September, temperatures are at their peak, with a minimum of 13°C (56°F), an average of 25°C (77°F), and a maximum that can reach up to 36°C (98°F). The month experiences considerable rainfall, with 120 mm (4.7 in) over about 12 days, while humidity levels linger around 75%. In contrast, November brings a notable drop in temperatures, with a minimum dipping to -2°C (28°F) and an average of only 13°C (56°F), peaking at 28°C (83°F). Precipitation decreases to 45 mm (1.8 in) over 8 days, and humidity rises to 84%. For more details on November weather, you can visit Si'an weather in November.
September weather features significantly warmer temperatures, with average highs reaching 36°C (98°F) and a comfortable average of 25°C (77°F). In contrast, December experiences much cooler conditions, where daytime highs typically reach only 23°C (73°F) and the average temperature drops to 7°C (44°F). While September is characterized by higher humidity at 75% and greater precipitation of 120 mm over 12 days, December sees a reduction in rainfall, totaling 52 mm over just 8 days, with humidity slightly increasing to 77%. For more detailed insights, you can check Si'an weather in December.
As September unfolds in Si'an, the weather transitions significantly, marking a departure from the summer heat. With a maximum temperature soaring to a warm 36°C, average daytime comforts settle around a pleasant 25°C, while nights bring a refreshing dip to 13°C. This month is also characterized by increased humidity levels around 75%, combined with 120 mm of rainfall over 12 days, hinting at the onset of the wetter season. Engaging in outdoor activities may require some planning around these rainier days, but the beautifully balanced temperatures make it an appealing time to explore the vibrant landscapes of Si'an. For more detailed insights, visit Si'an Climate.