September Weather in Longmen, China

Last updated: August 21, 2025

In September, Longmen, China experiences a dynamic climate characterized by a maximum temperature reaching 36°C (96°F), an average of 23°C (74°F), and a minimum of 16°C (60°F). This month marks a transition as the region receives approximately 225 mm (8.9 in) of precipitation over about 17 days, contributing to a relatively high humidity level of 77%. As summer gives way to autumn, the weather invites both warmth and occasional rain, making it a unique time for visitors to explore the area's natural beauty while preparing for changing conditions.

September Temperature in Longmen

In September, Longmen starts to transition from the sweltering summer heat to more comfortable autumn temperatures. With a minimum of 16°C (60°F) and reaching a maximum of 36°C (96°F), the air remains warm but less oppressive than in the height of summer. The average temperature settles around 23°C (74°F), making this month a delightful time for outdoor activities as humidity begins to dip. This gradual cooling trend hints at the changing seasons, following the peak summer heat, while still offering plenty of sunshine for those lingering late-summer adventures. As the month progresses, it's an excellent opportunity to enjoy the vibrant landscapes of Longmen with milder and more pleasant weather.

September Weather in Longmen: Daily Temperature Highs, Lows, and Averages

The chart illustrates September temperature patterns in Longmen, showcasing daily minimum, maximum, and average temperatures. It highlights the typical range of temperatures throughout the month, providing insights into weather trends. In Longmen, September typically has an average temperature of {2}°C ({3}°F), with highs reaching up to {4}°C ({5}°F) and lows dropping to around {6}°C ({7}°F).
JanFebMarAprMayJunJulAugSepOctNovDec454857647076818373635546
Data source: Temperature data for Longmen generated using information from the Copernicus Climate Change Service.
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The average of daily temperatures (24 hours) calculated across all days in the month.

September Precipitation in Longmen

In September, Longmen experiences a notable uptick in precipitation, receiving 225 mm (8.9 in) of rain over the course of 17 days. This increase marks a significant contribution to the annual rainfall, following the summer months when July holds the record with 265 mm (10.4 in). As the region transitions into autumn, the rainfall patterns indicate a gradual shift from the intense summer deluge to more moderate, yet consistent, moisture levels. The trend of elevated precipitation in September often supports the lush greenery characteristic of Longmen, making the area vibrant and lively as it prepares for the cooler months ahead. As the year progresses, September stands out as a key month in maintaining the region's hydrological balance.

September Precipitation Trends in Longmen

The chart displays monthly precipitation patterns in Longmen, with values for each month alongside September’s data, which is highlighted for easy comparison. It shows the amount of precipitation, providing insights into how September’s conditions compare to those of other months. In Longmen, September typically receives around {2} mm ({3} inches) of precipitation spread over approximately {4} days.
JanFebMarAprMayJunJulAugSepOctNovDec42671371851772152651612261607638
Data source: Precipitation data for September generated using information from the Copernicus Climate Change Service.
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September Humidity in Longmen

In Longmen, China, September marks a notable transition in humidity as it dips to 77%, down from the summer highs of 87% in July and 85% in August. This decrease signals the gradual shift towards autumn, providing a brief respite from the intense summer humidity. Starting the year with a higher average of 72% in January, the humidity steadily climbed through the spring and summer months, peaking in March before beginning its descent in September. This pattern indicates a natural rhythm, where the region experiences peak moisture in the warmer months, followed by a gentle decline as cooler weather approaches, while still maintaining relatively high levels—averaging around 81% in the following months of October and December.

September Average Humidity in Longmen

This chart illustrates the average monthly humidity levels in Longmen, with September’s data highlighted for easy comparison. It shows the fluctuation in humidity throughout the year, helping you understand how conditions vary by season. In September, average humidity in Longmen is approximately {2}%, offering insight into how humid the weather typically is during this month.
JanFebMarAprMayJunJulAugSepOctNovDec72%76%87%82%83%84%87%85%77%81%86%81%
Data source: Humidity data for September generated using information from the Copernicus Climate Change Service.

September UV Index in Longmen

As September rolls into Longmen, China, the UV Index remains at a notable 11, indicating an extreme exposure category, similar to the intensity felt throughout the summer months. This consistency in high UV levels, with a burn time reduced to just 10 minutes, calls for cautious sun protection as many summer activities continue into early fall. Following the peak of UV Index 12 in July and August, the slight dip to 11 still emphasizes the need for vigilance when outdoors. Whether you're soaking up the sun or enjoying outdoor adventures, navigating September's UV rays warrants awareness and proactive measures. For more detailed information, visit Longmen UV Index.

Maximum UV Index Levels in Longmen for September

The chart shows the monthly maximum UV Index (UVI) for Longmen in September, representing the highest UV radiation level. The UVI measures the intensity of ultraviolet radiation from the sun, indicating the potential risk of sunburn and UV-related health issues. In September, the maximum UV index in Longmen typically reaches {2}, which falls under the {3} exposure category.
JanFebMarAprMayJunJulAugSepOctNovDec568101111121211964
Data source: Longmen September UVI data generated using information from the Copernicus Climate Change Service.

UV Risk Categories

  •  Extreme (11+): Avoid the sun, stay in shade.
  •  Very High (8-10): Limit sun exposure.
  •  High (6-7): Use SPF 30+ and protective clothing.
  •  Moderate (3-5): Midday shade recommended.
  •  Low (0-2): No protection needed.

September Sunshine in Longmen

As summer fades, September in Longmen, China, continues to bask in the glow of abundant sunshine, boasting 218 hours of sunlight. This month marks a transition from the peak summer brightness of August, which dazzles with a remarkable 319 hours. Following the trend of increasing daylight hours from January's modest 124 hours, the climb peaks in July before gracefully tapering off. September’s sunshine levels reflect the tail end of the season, providing a warm and vibrant backdrop for outdoor activities. As the days grow shorter heading into autumn, the lingering sunlight offers a gentle reminder of summer's warmth, while preparing for the seasonal shift that follows in October with a notable drop to 151 hours.

Monthly Sunshine Duration in Longmen: September Highlighted

The September sunshine duration represents the total number of hours Longmen experiences direct sunlight during the month of September, excluding cloudy or obstructed periods. This chart compares the sunshine duration of September with the other months of the year.
JanFebMarAprMayJunJulAugSepOctNovDec124h171h204h229h250h262h294h319h218h151h151h151h
Data source: Longmen September Sunshine duration data generated using information from the Copernicus Climate Change Service.

Chance of Sun in Longmen During September

As summer transitions into autumn, September in Longmen, China, offers a fairly promising chance of sunny weather with a 35% likelihood of sunshine. This marks a slight uptick compared to the preceding months of August and July, which experience 27% and 33% chances of sun, respectively. Interestingly, September’s sunny prospects are akin to those of January and December, showcasing seasonal variations that appear more favorable during the tail end of summer. As the year progresses, the likelihood of sunshine dips dramatically in the following months, particularly in April and May, when it plummets to 15%. Thus, September stands out as a favorable time to enjoy the outdoors, just before the cooler and cloudier days of autumn fully settle in.

Percentage of Sunny Days in September in Longmen

The chart illustrates the percentage of sunny days in Longmen throughout the year, with September highlighted. It highlights the variation in sunshine across each month and provides an overview of the typical frequency of sunny days, offering insights into how often Longmen experiences clear skies throughout the year.
JanFebMarAprMayJunJulAugSepOctNovDec36%32%26%15%15%15%33%27%35%19%28%34%
Data source: Longmen September chance of sun data, generated using information from the Copernicus Climate Change Service.

Daylight Hours in Longmen in September

As summer fades, September in Longmen, China ushers in a gradual reduction in daylight, offering 12 hours of sunlight each day. This marks a subtle decline from the vibrant 14 hours enjoyed in June, transitioning from the long, sunlit days of summer to the softer light of autumn. The rhythm of daylight throughout the year is distinctly echoed; it begins with shorter hours in January, steadily increasing through the spring months, reaching a peak in June before tapering off again as the year progresses toward winter. This cyclical pattern not only highlights the characteristic rhythm of seasonal change but also serves as a reminder of nature’s beautiful transitions.

Average Daylight Hours in Longmen for September

The chart illustrates the variation in daylight duration in Longmen throughout the year, with September highlighted. It shows the monthly changes in daylight hours, calculated by summing the hours between sunrise and sunset.
JanFebMarAprMayJunJulAugSepOctNovDec10h 23m11h 5m11h 59m12h 55m13h 41m14h 5m13h 53m13h 12m12h 19m11h 23m10h 35m10h 11m
Data source: Longmen daylight hours, calculated by summing the hours between sunrise and sunset for each day.

September Winds in Longmen

In Longmen, China, September brings a gentle but noticeable increase in average wind speed, reaching 1.6 m/s (4 mph)—the highest for the month and a refreshing shift from the summer months. This uptick suggests a transition into the fall season, where cooler breezes begin to replace the stillness of summer. Throughout the year, wind speeds hover around 1.2 to 1.5 m/s, with the slight rise in September hinting at greater atmospheric changes ahead. As the city prepares for autumn, this whisper of wind serves as a precursor to the crisper days that lie ahead, inviting inhabitants to embrace the changing climate.

Average September Wind Speed in Longmen

The chart displays monthly wind speed patterns in Longmen, with values for each month shown alongside September's data, which is highlighted for easy comparison. It illustrates the average wind speed, offering insights into how September's wind conditions compare to the rest of the year.
JanFebMarAprMayJunJulAugSepOctNovDec1.31.41.51.41.31.31.31.41.6 m/s1.31.21.2
Data source: Longmen September wind data, generated using information from the Copernicus Climate Change Service.

How September Weather in Longmen Compares to Other Months

Weather in Longmen varies notably across the year, with each month offering distinct climate conditions. This page compares September’s weather to other months in Longmen, focusing on differences in temperature, rainfall, humidity, and UV levels.

In September, the weather is characterized by much warmer temperatures, with averages reaching around 23°C (74°F) and maximums soaring up to 36°C (96°F). This month also sees considerable precipitation, accumulating to 225 mm (8.9 in) over 17 days, accompanied by high humidity levels of 77%. In stark contrast, January experiences much cooler conditions, with average temperatures dipping to 7°C (45°F) and maximums only reaching 15°C (59°F). Additionally, January has significantly less precipitation, totaling just 42 mm (1.7 in) across 8 days and a slightly lower humidity of 72%. For more detailed weather information, you can visit Longmen weather in January.

September and February present contrasting weather patterns. September typically boasts warmer temperatures, with a minimum of 16°C (60°F) and an average high of 36°C (96°F), alongside significant rainfall totaling 225 mm (8.9 in) over 17 days, resulting in high humidity at 77%. In stark contrast, February experiences much cooler conditions, featuring a minimum temperature of 0°C (32°F) and an average high of 25°C (77°F), with only 67 mm (2.7 in) of precipitation over just 9 days, maintaining a slightly lower humidity level of 76%. For more specific insights into February weather, you can refer to Longmen weather in February.

When comparing the weather in September and March, notable differences emerge. September typically sees a warmer climate, with minimum temperatures around 16°C (60°F) and maximums reaching up to 36°C (96°F), while March experiences cooler temperatures, ranging from a minimum of 5°C (42°F) to a maximum of 30°C (87°F). In terms of precipitation, September is significantly wetter, with 225 mm (8.9 in) falling over 17 days compared to March's 137 mm (5.4 in) over 15 days. Additionally, humidity levels are slightly higher in March at 87%, compared to 77% in September. For a more detailed look at March weather, visit Longmen weather in March.

September and April present contrasting weather conditions. In September, temperatures range from a minimum of 16°C (60°F) to a scorching maximum of 36°C (96°F), with an average of 23°C (74°F). The month is also quite wet, experiencing 225 mm (8.9 in) of precipitation over 17 days and an average humidity of 77%. In contrast, April is cooler, with temperatures ranging from a minimum of 8°C (46°F) to a maximum of 33°C (92°F), averaging 18°C (64°F). The month features slightly less rainfall at 185 mm (7.3 in) spread over 16 days and higher humidity at 82%. For more detailed information on April weather, you can visit Longmen weather in April.

In September, temperatures tend to soar, with minimums averaging around 16°C (60°F) and maximums reaching as high as 36°C (96°F). The month brings significant rainfall, with an average precipitation of 225 mm (8.9 in) over 17 days, creating a humid atmosphere with a humidity level of 77%. In contrast, May experiences cooler temperatures, with minimums at 11°C (52°F) and an average of 21°C (70°F), peaking at 35°C (95°F). Rainfall in May is relatively lower at 177 mm (7.0 in) over the same number of rainy days, but the humidity is slightly higher at 83%. For a closer look at the weather specifics during May, you can check out Longmen weather in May.

In comparing the weather between September and June, we see some noticeable similarities and differences. September experiences slightly warmer temperatures, with an average of 23°C (74°F) and a maximum of 36°C (96°F), compared to June's average of 24°C (76°F) and a maximum of 35°C (96°F). Precipitation levels are quite similar, with September receiving 225 mm (8.9 in) over 17 days, just slightly higher than June's 215 mm (8.5 in) over 16 days. However, September's humidity sits at 77%, while June is a bit more humid at 84%. To explore more about June weather in Longmen, you can check out Longmen weather in June.

When comparing the weather in September and July, it's clear that July tends to be hotter and more humid. In July, temperatures range from a minimum of 20°C (67°F) to a maximum of 38°C (101°F), with an average of 27°C (81°F). In contrast, September features a slightly cooler temperature profile, with a minimum of 16°C (60°F), an average of 23°C (74°F), and a maximum of 36°C (96°F). Additionally, both months experience significant rainfall, with July recording 265 mm (10.4 in) over 18 days, while September sees 225 mm (8.9 in) over 17 days. It's worth noting that humidity is also higher in July at 87%, compared to September's 77%. For a more detailed look at July weather, check out Longmen weather in July.

September's weather is characterized by a slight dip in temperature compared to August, with minimums averaging around 16°C (60°F) and maximums reaching 36°C (96°F). The average temperature is cooler at 23°C (74°F), while August boasts a higher average of 28°C (83°F) and maximum temperatures peaking at 39°C (102°F). Precipitation in September is more significant, totaling 225 mm (8.9 in) over 17 days, compared to August's 161 mm (6.3 in) across 14 days. Moreover, humidity levels are slightly lower in September at 77%, compared to a higher 85% in August, giving a somewhat more comfortable feel as summer transitions to fall. For further insights on August weather in the region, check Longmen weather in August.

September and October exhibit notable differences in weather conditions. In September, temperatures range from a minimum of 16°C (60°F) to a scorching maximum of 36°C (96°F), with an average of 23°C (74°F). The month is characterized by high humidity at 77% and significant rainfall, accumulating 225 mm (8.9 in) over 17 days. In contrast, October sees a drop in temperatures, with lows of 11°C (51°F) and highs reaching 34°C (93°F), averaging around 17°C (64°F). Precipitation decreases to 160 mm (6.3 in) over 16 days, and humidity increases slightly to 81%. For more details on the October weather in Longmen, visit Longmen weather in October.

September weather typically features warmer temperatures, with averages around 23°C (74°F) and highs reaching up to 36°C (96°F). The month is also characterized by significant rainfall, totaling 225 mm (8.9 in) over 17 days, combined with a humidity level of 77%. In contrast, November brings cooler conditions, with average temperatures dropping to 13°C (55°F) and maximums around 25°C (76°F). The precipitation is markedly lower at 76 mm (3.0 in) over just 11 days, though humidity slightly increases to 86%. For more details on weather conditions in November, you can visit Longmen weather in November.

September and December present strikingly different weather conditions. In September, temperatures range from a mild 16°C (60°F) at night to a scorching 36°C (96°F) during the day, with an average of 23°C (74°F). The month is characterized by significant rainfall, totaling 225 mm (8.9 in) over 17 days, accompanied by a humidity level of 77%. In contrast, December experiences much cooler temperatures, with a minimum of 0°C (33°F), an average of 8°C (47°F), and a maximum of 17°C (63°F). The precipitation drops dramatically to 38 mm (1.5 in) over just 9 days, while humidity slightly increases to 81%. For a deeper understanding of December weather conditions, you can refer to Longmen weather in December.

Compare Longmen's Climate with Cities Worldwide

Conclusion: What to Expect From September Weather in Longmen

As September unfolds in Longmen, the weather shifts notably from the sweltering summer months. With a maximum temperature that still reaches highs of 36°C (96°F), it’s a transitional time where the average cools to a more pleasant 23°C (74°F). The month brings increased precipitation, with rain refreshing the landscape on about 17 days, leading to a humidity level of 77% that fosters a lush environment. This blend of heat and moisture makes September a unique month, striking a balance between lingering summer warmth and the refreshing onset of fall. For a detailed overview of the climate year-round, visit Longmen Climate.