Last updated: August 21, 2025
September in Xi'an, China showcases a delightful transition from summer's heat to the cooler embrace of autumn. With a maximum temperature peaking at 35°C (95°F) and an average of 21°C (70°F), days can still feel warm. However, as evening falls, temperatures dip to a refreshing 10°C (51°F). This month also experiences significant rainfall, with 174 mm (6.8 in) spread across 13 days, contributing to a humid atmosphere with an average humidity level of 78%. Whether you’re exploring historic sites or enjoying local cuisine, the varying weather makes September a dynamic time to visit Xi'an.
In September, Xi'an experiences a delightful transition as summer ebbs away, bringing more temperate conditions to the region. With a minimum temperature of 10°C (51°F) and an average of 21°C (70°F), the city enjoys a comfortable climate perfect for exploring its rich history and culture. As the maximum temperature peaks at 35°C (95°F), the days are still warm, yet noticeably cooler than the sweltering heat of July and August. This shift provides a refreshing outdoor experience, making September an ideal time to visit Xi'an and witness the stunning contrasts of its historical landscape.
September marks a significant shift in precipitation patterns in Xi'an, China, as the city experiences its wettest month of the year. With 174 mm (6.8 in) of rainfall spread over 13 days, the arrival of autumn ushers in a much-needed relief from the summer heat and dryness. This increase is a stark contrast to the relatively dry months of January through August, where rainfall steadily built up to a peak in September. The data reveals a clear trend of rising precipitation leading into fall, highlighting September as a pivotal month in the region's climatic cycle. This seasonal surge not only rejuvenates the environment but also sets the stage for the milder, cooler days that fall brings.
As summer fades into autumn, September in Xi'an, China, experiences a shift in humidity, averaging a comfortable 78%. This slight decrease from the high levels of the preceding months—where July and August hover around 76% and 72%—marks a transition towards the drier fall season. Interestingly, this month sits just above May’s lower point of 68% but still below the approaching winter months of October and November, which see humidity levels rising again to 85% and 82% respectively. This trend highlights the fluctuation in humidity throughout the year, revealing a pattern where late summer gives way to a more humid autumn before the winter months bring on more moisture.
As September rolls into Xi'an, the UV Index begins to show signs of mild decrease, dropping to 9, which still qualifies as very high. This slight dip marks a transition from the peak summer months, where the index rested at a blistering 10 from May to August. The burn time during this period remains just 15 minutes, urging sun seekers to take precautions seriously. As we look ahead, October's UV Index is expected to further decline to 7, indicating a shift toward safer sun exposure, yet September still demands respect for the sun’s powerful rays. For more detailed information on the UV levels throughout the year, check out Xi'an UV Index.
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September in Xi'an, China, brings a gentle transition from the sun-drenched days of summer to the cooler hues of autumn. With 239 hours of sunshine, it's clear that while daylight begins to wane, the warmth still lingers. This month follows a vibrant summer peak, where July basked in a generous 323 hours of golden rays, and August wasn't far behind with 318 hours. September’s decrease in sunlight is a natural ebb, hinting at the approaching fall, yet it stands out positively compared to the chillier months ahead, such as October with 221 hours. This gradual shift not only marks the changing season but also offers a perfect opportunity to embrace the beautiful landscapes of Xi'an under its warm, albeit dwindling, sunlight.
In September, Xi'an, China experiences a 44% chance of sunny weather, positioning it as a transitional month as summer fades into autumn. This percentage is notably higher than the typically cloudier months of April (28%) and May (34%), yet it trails behind the brighter late winter and early spring months of November and December, which showcase sun probabilities around 62% and 63% respectively. As the city moves from the sweltering heat of summer, with slightly better chances in July (45%) and August (39%), September remains a favorable time for outdoor activities, with a decent likelihood of sunshine lending itself to exploration and enjoyment of Xi'an's rich historical landscape.
As September arrives in Xi'an, China, the daylight duration begins its gradual decline, offering approximately 12 hours of sunlight. This marks a subtle transition from the peak summer months, where July and June bask in 14 hours of daylight, to the shorter, cooler days of autumn. Following a vibrant summer, the diminishing sunlight in September reflects the region’s shift from the longer, sun-kissed days of mid-year to the crisper, more introspective moments of fall. As daylight hours continue to wane into October and November, the rhythm of the seasons invites a contemplative embrace of the changing landscape and cooler temperatures, signaling the approach of winter.
In September, Xi'an experiences a gentle breeze with an average wind speed of 1.8 m/s (4 mph), signaling the transition from summer's warmth into the cooler autumn months. This consistent wind speed mirrors the moderate gusts from the previous winter and spring, creating a refreshing atmosphere as the leaves begin to change color. The month’s wind is slightly more brisk than the preceding peak summer months, where speeds dipped to 1.6 m/s. As the city embraces the onset of fall, the stable conditions offer a perfect backdrop for residents and visitors to explore the rich history and vibrant culture of Xi'an. The winds of September, while not particularly strong, act as a reminder of the seasonal shift and the beauty that accompanies it.
Weather in Xi'an varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Xi'an, focusing on differences in temperature, rainfall, humidity, and UV levels.
September and January present stark contrasts in weather. In September, temperatures range from a mild 10°C (51°F) at night to a warm 35°C (95°F) during the day, accompanied by a high humidity level of 78% and significant rainfall of 174 mm over 13 days. In contrast, January plunges into the chill of winter, featuring frigid temperatures as low as -15°C (6°F) at night, with a meager average of 1°C (35°F) and daytime highs reaching only 15°C (59°F). The precipitation is considerably lower at 18 mm, occurring over just 3 days, and humidity drops to 70%. For more specific details, you can check out Xi'an weather in January.
September and February present a stark contrast in weather conditions. September boasts a wide temperature range, with minimums of 10°C (51°F) and maximums reaching up to 35°C (95°F), contributing to an average of 21°C (70°F). This month experiences significant rainfall, totaling 174 mm (6.8 in) over 13 days, while maintaining a humidity level of 78%. In contrast, February is much colder, with a minimum temperature of -13°C (9°F) and a much narrower maximum of 24°C (76°F), resulting in an average of only 5°C (41°F). Precipitation in February is considerably lower, with only 21 mm (0.8 in) over just 3 days and a relative humidity of 80%. For more details on the weather during this time, you can check Xi'an weather in February.
September and March present a striking contrast in weather conditions. September boasts warm temperatures with a minimum of 10°C (51°F) and an average high of 21°C (70°F), reaching up to 35°C (95°F) on warmer days. However, this month also experiences significant rainfall, with 174 mm (6.8 in) spread over 13 days, leading to a humidity level of 78%. In contrast, March is considerably cooler, starting with a minimum temperature of -2°C (28°F) and an average of 11°C (53°F), peaking at 28°C (83°F). Precipitation is much lower, totaling 38 mm (1.5 in) over just 6 days, with humidity slightly higher at 83%. For more detailed insights, visit Xi'an weather in March.
In September, the weather exhibits a broader temperature range, with minimums reaching 10°C (51°F) and maximums soaring up to 35°C (95°F), leading to an average temperature of 21°C (70°F). The month experiences significant rainfall, totaling 174 mm (6.8 in) over about 13 days, accompanied by a humidity level of 78%. In contrast, April tends to be much cooler, with temperatures ranging from a low of 2°C (36°F) to a high of 33°C (92°F), resulting in an average temperature of 16°C (62°F). The precipitation in April is notably lower at 57 mm (2.2 in) spread over 8 days, along with a slightly higher humidity of 81%. For a detailed look at April’s climate, you can check Xi'an weather in April.
In comparing the weather between September and May, we can see some interesting similarities and differences. Both months share an average temperature of 21°C (70°F), with highs reaching up to 35°C (95°F) in September and 96°F in May. However, September tends to be more humid, with an average humidity of 78% compared to May's 68%. Additionally, September experiences significantly more rainfall, with 174 mm (6.8 in) over about 13 days, while May has only 65 mm (2.6 in) of precipitation over 7 days. For those interested in the specifics of May's weather, more information is available at Xi'an weather in May.
In comparing the weather of September and June, June typically experiences warmer temperatures, with average highs reaching 37°C (100°F) compared to September's maximum of 35°C (95°F). However, September has a cooler minimum temperature of 10°C (51°F), which is noticeably lower than June’s minimum of 13°C (56°F). Additionally, September sees more precipitation overall, with 174 mm (6.8 in) distributed over 13 days, while June has less rainfall at 124 mm (4.9 in) across 9 days. The humidity levels are similar, with September averaging 78% and June at 74%. For more specific details about June weather, you can visit this link: Xi'an weather in June.
In comparing the weather between September and July, it's clear that July tends to be hotter, with average temperatures reaching 27°C (81°F) and maximums soaring to 40°C (104°F). In contrast, September boasts a milder average temperature of 21°C (70°F), with maximums reaching 35°C (95°F). While both months see a fair amount of rainfall, September experiences higher precipitation at 174 mm (6.8 in) over 13 days, compared to July's 123 mm (4.8 in) over just 10 days. Humidity levels are slightly higher in September at 78%, while July maintains a comfortable 76%. For more details on July weather specifics, you can check Xi'an weather in July.
In comparing the weather between September and August, September experiences a significant drop in temperature, with average highs of 35°C (95°F) compared to August's more scorching 39°C (102°F). The minimum temperatures also reflect this change, falling from 15°C (59°F) in August to 10°C (51°F) in September. Precipitation increases in September, with a total of 174 mm (6.8 in) over 13 days, compared to 125 mm (4.9 in) over 11 days in August. Additionally, September's humidity level rises slightly to 78%, while August holds a lower humidity of 72%. For more detailed information, you can check Xi'an weather in August.
September weather tends to be much warmer than October, with average temperatures ranging from a minimum of 10°C (51°F) to a maximum of 35°C (95°F). In contrast, October experiences cooler temperatures, with a minimum of 5°C (41°F) and a maximum of 29°C (85°F). September is also significantly wetter, receiving 174 mm (6.8 in) of precipitation over 13 days, while October sees less rainfall at 90 mm (3.5 in) over 12 days. Additionally, October experiences higher humidity at 85%, compared to September’s 78%. For a detailed look at October weather in Xi'an, check out Xi'an weather in October.
In September, the weather is warm, with temperatures ranging from a low of 10°C (51°F) to a high of 35°C (95°F), and an average of 21°C (70°F). The month experiences frequent rainfall, with 174 mm (6.8 in) of precipitation over 13 days, contributing to a relatively high humidity level of 78%. In contrast, November brings a significant drop in temperatures, with a minimum of -3°C (27°F) and an average of just 9°C (48°F), peaking at 24°C (75°F). Precipitation is much lower in November, totaling only 28 mm (1.1 in) across 6 days, and the humidity rises slightly to 82%. For more details, check Xi'an weather in November.
September and December present stark contrasts in weather. In September, temperatures vary significantly, ranging from a low of 10°C (51°F) to a high of 35°C (95°F), with an average of 21°C (70°F). The month is quite humid at 78% and sees substantial precipitation, totaling 174 mm (6.8 in) over 13 days. In contrast, December experiences much colder temperatures, with a minimum of -8°C (18°F), an average of 2°C (37°F), and a maximum of 15°C (59°F). The precipitation drops dramatically to just 9 mm (0.4 in) over only 2 days, while humidity remains relatively high at 80%. For more details on December weather, visit Xi'an weather in December.
As September rolls into Xi'an, the weather transforms dramatically, offering a delightful blend of warm days and cooler nights. With a maximum temperature that can soar up to 35°C (95°F), the days retain a lingering summer feel, while the average dips to a comfortable 21°C (70°F), making evenings perfect for outdoor activities. Yet, it’s not just warmth that characterizes this month—higher humidity levels and increased precipitation, with about 13 rainy days, mean you’ll want to have an umbrella handy. This unique interplay of elements makes September distinct, balancing the remnants of summer with hints of autumn. For those seeking detailed insights into what to expect, check out Xi'an Climate.