Last updated: February 24, 2025
September weather in Cahokia, United States showcases a captivating blend of warmth and humidity. With maximum temperatures soaring up to 35°C (95°F), the month averages a comfortable 23°C (73°F), while cooler evenings can drop to a minimum of 7°C (46°F). Rainfall is moderate, with a total of 58 mm (2.3 in) occurring over seven days, contributing to a humid environment, averaging 76% humidity. This dynamic weather pattern offers both sun-soaked afternoons and refreshing evening breezes, making September an intriguing month for residents and visitors alike.
As summer fades into autumn, September in Cahokia ushers in a delightful transition characterized by milder temperatures. With minimums around 7°C (46°F) and delightful averages reaching 23°C (73°F), this month offers a welcome reprieve from the sweltering heat of July and August. The maximum temperatures can still climb to 35°C (95°F), allowing for those late-summer outdoor activities to extend into early fall. Overall, September showcases a balanced climate, with gentle warmth inviting residents and visitors alike to explore the beauty of the season while enjoying the gradual shift in nature’s palette.
In September, Cahokia experiences a notable decline in precipitation, recording only 58 mm (2.3 in) across 7 days—the lowest monthly total of the year. This marks a shift from the wetter summer months, where August brought 131 mm (5.1 in) over 12 days, highlighting a transition towards the drier autumn period. As September wraps up the summer season, the reduced rainfall signals a gradual decrease in moisture as the year progresses, setting the stage for October's anticipated increase of 107 mm (4.2 in). This trend illustrates a seasonal rhythm that underscores Cahokia's climate variability, with September embodying a quieter, more stable weather pattern.
In Cahokia, United States, September marks the end of summer, bringing a noticeable dip in humidity levels, which settle at 76%. This decline continues a trend observed since late spring, where the humidity peaked in June at 83% before gradually decreasing. As the month progresses, the comfortable conditions often contrast sharply with the heavy, humid air of the warmer months, providing a refreshing change. Interestingly, this pattern sets the stage for the upcoming autumn months, where humidity holds steady at 76% in October before rising again in November and December, highlighting the region's transition into the cooler, more humid winter season. Overall, September serves as a pivotal month that bridges the gap between the sultry summer and the crisp fall.
In September, Cahokia experiences a UV Index of 9, placing it in the very high exposure category, similar to the peak summer months of June and July. As the summer sun begins to wane, residents should remain vigilant about sun protection, with a burn time of just 15 minutes for unprotected skin. Interestingly, the UV Index shows a gradual decline from the extreme levels of the preceding months but retains significant intensity, emphasizing the importance of continued sun safety. As the fall approaches, while the overall UV Index trend starts to drop, September still demands careful measures to shield against harmful rays. For more detailed insights into UV patterns, visit Cahokia UV Index.
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As summer wanes and autumn approaches, September in Cahokia continues to bask in the afterglow of sunny days, boasting 291 hours of sunshine. This month marks a delightful transition, slightly lower than the sun-drenched peak of July, which recorded an impressive 349 hours. However, September still enjoys plenty of bright days, maintaining a robust average that outshines the earlier months of the year, such as January with just 127 hours. With a gradual decline in daylight hours heading into the cooler months, September's sunlight serves as a gentle reminder of the warmth of summer, setting the stage for the cozy embrace of fall.
In September, Cahokia experiences a notable uptick in sunny weather, with a 64% chance of sunshine that makes it one of the brightest months of the year. This shift follows the warmer summer months, where July and August still hold their own with chances around 51% and 47%, respectively. As summer fades, the increase in sunny days in September suggests a delightful transition, providing ideal conditions for outdoor activities and leisurely pursuits. This trend highlights the month as a standout time to enjoy the pleasant weather before the cooler autumn months set in, where the chances dip again to 40% in October.
As summer gracefully transitions into fall, September in Cahokia sees daylight duration dip to 12 hours, marking a subtle shift from the longer days of the preceding months. This decrease reflects a gradual descent from the peak of 14 hours experienced in June through August. While September enjoys more light than the autumn months ahead, it signals the onset of shorter days and cooler weather, inviting residents to embrace the beauty of changing seasons. The cyclical nature of daylight here offers a poignant reminder of nature’s rhythm, as evening shadows begin to lengthen and autumn prepares to take the stage.
As August's gentle breezes give way to September, Cahokia experiences a pleasant shift in wind patterns. The average wind speed rises to 3.0 m/s (7 mph), marking a welcome change that rekindles the vigor of late summer. This increase reflects a gradual recovery from the lighter winds of July and August, which had dipped to 2.0 m/s (5 mph) and 2.3 m/s (5 mph), respectively. Notably, September’s winds are a precursor to the autumn season, where gusty conditions often return. As the month unfolds, residents can expect conditions that are both refreshing and invigorating—setting the stage for the brisk winds of October, anticipated to reach 3.4 m/s (8 mph). This month’s breezy character serves as a reminder that summer quietly transitions into fall, inviting people outdoors to embrace the shifting season.
The weather in Cahokia changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of September's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Cahokia and find detailed weather information for every month.
September and January present stark contrasts in weather. In September, temperatures range from a mild 7°C (46°F) at night to a high of 35°C (95°F) during the day, with an average of 23°C (73°F), making it a warm month. The humidity is relatively high at 76%, and there is some precipitation, totaling 58 mm (2.3 in) over 7 days.
In contrast, January is characterized by much colder temperatures, with a minimum of -21°C (-5°F) and a maximum of 20°C (68°F), averaging around 0°C (33°F). This month also sees higher precipitation at 79 mm (3.1 in) over 8 days, along with increased humidity levels at 82%. For more details on the specific conditions in January, you can check Cahokia weather in January.
September and February present contrasting weather conditions. In September, temperatures range from a minimum of 7°C (46°F) to a sweltering maximum of 35°C (95°F), with an average of 23°C (73°F). The month receives about 58 mm (2.3 in) of precipitation over 7 days, with humidity levels around 76%. In stark contrast, February experiences much colder temperatures, with a minimum of -19°C (-2°F) and an average of 2°C (36°F), peaking at 25°C (77°F). This month tends to be wetter, with 82 mm (3.2 in) of rainfall spread over 10 days and a higher humidity of 80%. For more detailed information, you can check Cahokia weather in February.
September and March present contrasting weather experiences, showcasing the transition between summer and spring in Cahokia. In September, temperatures range from a mild 7°C (46°F) at night to a warm 35°C (95°F) during the day, with an average of 23°C (73°F). The month sees relatively lower precipitation of 58 mm (2.3 in) over about 7 days, and humidity levels sit at 76%. In stark contrast, March brings much cooler temperatures, with nighttime lows plunging to -16°C (3°F) and daytime highs reaching 28°C (82°F), producing an average temperature of only 8°C (48°F). Additionally, March experiences significantly higher precipitation at 134 mm (5.3 in) across 12 days and slightly elevated humidity at 80%. For further details on the weather patterns in March, you can check Cahokia weather in March.
When comparing the weather in September and April, a stark contrast is evident. September boasts warmer temperatures, with averages around 23°C (73°F) and highs reaching up to 35°C (95°F), while April's temperatures are significantly cooler, ranging from a minimum of -4°C (25°F) to a maximum of 31°C (88°F) and an average of just 13°C (56°F). Additionally, September experiences less precipitation with about 58 mm (2.3 in) over 7 days, compared to April's heavier rainfall of 135 mm (5.3 in) across 11 days. Humidity levels are fairly similar, hovering around 76% in September and 80% in April. For a more detailed look at April weather, check out Cahokia weather in April.
In September, the weather tends to be warmer than in May, with average temperatures around 23°C (73°F) and a maximum reaching up to 35°C (95°F). In contrast, May offers cooler averages at 20°C (68°F) and a maximum of 34°C (94°F). However, May is marked by significantly higher precipitation, totaling 146 mm (5.7 in) over 14 days, compared to September's 58 mm (2.3 in) over just 7 days. Additionally, humidity levels are slightly higher in May at 82%, while September experiences 76% humidity. For more details on the weather specifics in May, you can visit Cahokia weather in May.
When comparing the weather of September and June, we see some notable differences. September boasts a broader temperature range, with minimums dipping to 7°C (46°F) and maximums reaching up to 35°C (95°F), averaging 23°C (73°F). In contrast, June presents a milder minimum temperature of 12°C (54°F) and slightly higher averages of 25°C (77°F), with maximums peaking at 36°C (97°F). Precipitation levels also vary, as June experiences more rainfall, totaling 94 mm (3.7 in) across 11 days, while September sees less, with 58 mm (2.3 in) over 7 days. Additionally, June has a higher humidity level of 83% compared to September's 76%. For more detailed information on June's weather, you can check Cahokia weather in June.
When comparing the weather in July and September, a noticeable shift in temperature and precipitation patterns can be observed. July features warmer temperatures, with an average of 27°C (80°F) and highs soaring up to 38°C (102°F), while September experiences cooler conditions, with an average temperature of 23°C (73°F) and maximums reaching 35°C (95°F). Additionally, July sees a higher level of humidity at 81% compared to September's 76%. Precipitation levels are also elevated in July, with about 92 mm (3.6 in) over 10 days, compared to September's 58 mm (2.3 in) over 7 days. For more detailed information, you can check out this link: Cahokia weather in July.
In comparing the weather of September and August, September experiences slightly cooler temperatures, with minimums dropping to 7°C (46°F) compared to August's 12°C (55°F). The average temperature in September is around 23°C (73°F), which is a bit lower than August's average of 25°C (77°F). However, September sees less rainfall, with 58 mm (2.3 in) over 7 days, while August has a higher precipitation level of 131 mm (5.1 in) over 12 days. Humidity levels are also marginally lower in September at 76%, compared to 80% in August. For more detailed insights into the weather patterns, you can visit Cahokia weather in August.
September and October present a stark contrast in weather patterns. In September, temperatures range from a mild 7°C (46°F) at night to a high of 35°C (95°F) during the day, with an average temperature of 23°C (73°F). The month sees moderate precipitation, totaling 58 mm (2.3 in) over 7 days, accompanied by a humid atmosphere at 76%. In contrast, October experiences cooler temperatures, with nighttime lows dropping to -3°C (26°F) and a significant decline in the daily average to 15°C (60°F). Despite the max temperature remaining close at 34°C (94°F), October brings increased rainfall, totaling 107 mm (4.2 in) spread over 11 days, while maintaining the same humidity level of 76%. For more detailed information about weather specifics, check out Cahokia weather in October.
In September, the weather is generally warm, with temperatures ranging from a mild 7°C (46°F) at night to a hot 35°C (95°F) during the day, while averaging around 23°C (73°F). The month experiences moderate rainfall, totaling 58 mm (2.3 in) across about 7 days, and humidity is relatively high at 76%. In contrast, November brings a significant shift in conditions, with temperatures dropping to a minimum of -12°C (10°F) and an average of 7°C (45°F), peaking at 25°C (78°F). Precipitation in November increases slightly to 75 mm (3.0 in) over 9 days, and humidity rises to 85%. For more details on November weather, check out Cahokia weather in November.
The weather in September and December exhibits stark contrasts, reflecting the transition from summer to winter. In September, temperatures can range from a mild 7°C (46°F) at night to a sweltering 35°C (95°F) during the day, accompanied by an average of 23°C (73°F) and relatively moderate humidity at 76%. In contrast, December brings a dramatic drop in temperatures, with nighttime lows plummeting to -16°C (3°F) and daytime highs reaching only 23°C (74°F), averaging around 4°C (40°F). The precipitation levels are somewhat similar, with September receiving 58 mm (2.3 in) and December 64 mm (2.5 in), although December's increased humidity at 86% adds to the chilly atmosphere. For more details, you can check out Cahokia weather in December.
As summer starts to fade, September in Cahokia presents a transition that is often marked by a delightful blend of warmth and refreshing breezes. Temperatures hover at a pleasant average, providing a much-needed reprieve from the relentless heat of July and August, while the notable humidity levels add a touch of stickiness typical of late summer. With precipitation appearing on about a quarter of the days, September also brings occasional showers that rejuvenate the landscape. This month is a unique time when the vibrant colors of fall begin to emerge, making it a splendid month for outdoor activities. For more detailed insights into the weather patterns and overall climate, check out Cahokia Climate.