Last updated: February 24, 2025
September in Grant Park offers a vibrant mix of weather characteristics that reflect the transition from summer to fall. With maximum temperatures soaring to 34°C (94°F), visitors can expect warm, sunny days, while the average temperature rests comfortably at 20°C (69°F). Nights can be cool, dipping to a minimum of 5°C (41°F), providing a refreshing contrast. This month sees moderate rainfall, with 77 mm (3.0 in) spread over approximately 8 days, contributing to the lushness of the park. Humidity levels hover around 80%, creating a tropical feel that enhances the beauty of the changing landscape. Overall, September presents an ideal time to explore Grant Park's natural splendor amidst its dynamic weather patterns.
September in Grant Park marks the transition from the sweltering summer months to the crispness of fall, with temperatures showcasing a delightful mix of warmth and early autumn chill. The average temperature settles around a comfortable 20°C (69°F), complemented by minimums that flirt with summer's remnants at 5°C (41°F). As daytime highs still reach a toasty 34°C (94°F), the month offers plenty of sunny days to bask outdoors, perfect for enjoying the park's vibrant atmosphere. This month acts as a gentle reminder of the upcoming seasonal shift, bridging the gap between the lingering warmth of summer and the cooling embrace of fall, making it an ideal time for outdoor adventures.
September in Grant Park sees a moderate precipitation level, with 77 mm (approximately 3.0 in) accumulating over 8 days. This marks a decrease from the heavier rains of May and June, where precipitation peaked at 161 mm (6.3 in) and 124 mm (4.9 in), respectively. As summer transitions into fall, the rainfall in September suggests a gradual decline in moisture, but it still provides a crucial replenishment as the region prepares for the upcoming dryer months. Remarkably, this month mirrors the drier tendencies of November and December, which both feature similar precipitation patterns, hinting at a consistent trend of reduced rainfall as the year draws to a close.
In September, Grant Park experiences a humidity level of 80%, keeping it relatively consistent with the preceding summer months. As the year progresses, the humidity shows a subtle upward trend in the spring, peaking at 85% in April before gradually decreasing to 79% in May. The summer months maintain a range that hovers between 80% and 82%, creating a comfortable atmosphere overall. As autumn approaches, humidity begins its ascent again, culminating in the increasingly moist conditions of late fall, highlighted by 88% in November. This cyclical nature of humidity reflects the distinct seasonal shifts that characterize Grant Park's climate.
As September rolls into Grant Park, the UV Index stands at 8, signifying a very high risk of harm from unprotected sun exposure, with a burn time of just 15 minutes. This slight decrease from the peak summer months, where the UV Index soared to 10, indicates that while the intensity of sunlight is beginning to relax, caution is still essential. The trend from summer shows a gradual decline in UV levels, yet September still demands vigilance for sun safety. With autumn on the horizon and the sun’s rays retaining potency, it's important to stay protected! For more detailed information, visit Grant Park UV Index.
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As summer fades into autumn, September in Grant Park offers a delightful 287 hours of sunshine, a charming continuation of the sun-drenched days that characterized the peak summer months. Following the highs of 353 hours in July and 334 hours in August, this month sees a gentle decline, yet still boasts abundant sunshine that invites outdoor activities and leisurely strolls. The gradual decrease in daylight hours is a prelude to the cooler fall days, contrasting with the warmer months while maintaining a bright charm. This trend of diminishing sunshine is mirrored in the months ahead, with October bringing 223 hours, showcasing the seasonal shift. In Grant Park, September truly embodies the vibrant transition from summer's warmth to the crispness of fall, offering plenty of sunny moments to savor.
In Grant Park, the weather in September marks a delightful transition toward sunnier days, boasting a 59% chance of sunshine. This significant increase in sunny conditions is a refreshing contrast to the earlier months, with only January and February barely scraping a quarter of sunshine. From the low 30s in spring to a peak of 45% in August, September stands out as the month that ushers in more consistent sunshine. As autumn approaches, the likelihood of clear skies offers a perfect backdrop for outdoor activities and gatherings, making it an ideal time to enjoy the vibrant colors of the changing season.
As the warm embrace of summer begins to wane in September, Grant Park experiences a gentle shift in daylight duration, offering 12 hours of daylight. This marks a gradual decline from the 14 hours enjoyed in the height of July, signaling the onset of autumn. Over the course of the year, the trend is clear: daylight starts plentiful in June and July, peaking at 15 hours, only to gradually recede as the days grow shorter. September’s softer light invites a moment of reflection before the briskness of October sets in, when daylight decreases to 11 hours. This rhythmic dance of sunlight not only highlights the changing seasons but also enhances the allure of Grant Park, making it a beautiful backdrop for enjoying the subtle transitions of nature.
As September rolls into Grant Park, the wind makes a thoughtful return, averaging 3.8 m/s (8 mph)—a notable uptick from the summer's gentle breezes. This month marks a transition, as the winds begin to regain strength after the calmest summer months, peaking in August at 2.7 m/s (6 mph). With fall approaching, September's winds hint at the changing seasons, setting the stage for the brisker gales of autumn. The trend showcases a gradual reinvigoration of wind speed as the year progresses, reflecting nature’s rhythm in this urban oasis. Embrace the refreshing gusts as they brush past, bringing a sense of renewal and anticipation for the vibrant tapestry of autumn that lies ahead.
The weather in Grant Park 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 Grant Park and find detailed weather information for every month.
September and January present stark contrasts in weather patterns. In September, temperatures range from a cool 5°C (41°F) at night to a warm average of 20°C (69°F) during the day, peaking at a scorching 34°C (94°F). This month also sees a fair amount of precipitation, totaling 77 mm (3.0 in) over approximately 8 days, with a humidity level of 80%.
In contrast, January experiences much harsher conditions, with temperatures dropping to a frigid minimum of -30°C (-22°F) and an average of -3°C (27°F), reaching a maximum of only 17°C (63°F). This winter month has slightly less precipitation at 69 mm (2.7 in) but maintains a high humidity level of 82%. For more detailed information, you can check Grant Park weather in January.
September and February present starkly contrasting weather conditions. In September, temperatures range from a minimum of 5°C (41°F) to a comfortable maximum of 34°C (94°F), with an average around 20°C (69°F). Humidity is relatively high at 80%, accompanied by around 77 mm (3.0 in) of precipitation over approximately 8 days. In contrast, February experiences much colder weather, with temperatures plunging to a minimum of -31°C (-24°F) and rising only to a maximum of 21°C (70°F), averaging -2°C (29°F). The humidity slightly increases to 83%, and the snowfall contributes to a total precipitation of 71 mm (2.8 in) over about 10 days. For more details about February weather, you can visit Grant Park weather in February.
September and March present a stark contrast in weather conditions. In September, temperatures range from a mild 5°C (41°F) at night to a warm 34°C (94°F) during the day, with an average of 20°C (69°F). The month experiences 77 mm (3.0 in) of precipitation over about 8 days and has a humidity level of 80%. On the other hand, March brings much colder temperatures, with lows plummeting to -18°C (-1°F) and highs reaching only 26°C (80°F), averaging just 5°C (41°F). This month sees slightly higher precipitation at 95 mm (3.7 in) spread over 12 days and a humidity level of 84%. For more detailed information, you can check Grant Park weather in March.
When comparing the weather in September and April, notable differences emerge. September typically sees warmer temperatures, with a minimum of 5°C (41°F), an average of 20°C (69°F), and a maximum of 34°C (94°F), while April experiences cooler conditions, starting with a minimum of -7°C (19°F) and an average of 10°C (50°F), peaking at 29°C (85°F). While September enjoys slightly less precipitation at 77 mm (3.0 in) over 8 days, April is notably wetter, averaging 120 mm (4.7 in) across 13 days. Furthermore, humidity levels are slightly higher in April at 85% compared to September’s 80%. For a detailed look at April's weather specifics, check here: Grant Park weather in April.
September and May present distinct weather patterns, showcasing a transition from the end of summer to early autumn. In September, temperatures range from a minimum of 5°C (41°F) to a maximum of 34°C (94°F), with an average of 20°C (69°F). This month experiences about 77 mm (3.0 in) of precipitation over eight days, and humidity hovers around 80%. In contrast, May has cooler minimum temperatures that can drop to -2°C (29°F), with an average of 17°C (62°F) and the same maximum of 34°C (94°F). However, it sees considerably more rainfall, totaling 161 mm (6.3 in) over 15 days, while humidity remains slightly lower at 79%. For further details on the weather patterns in May, you can check Grant Park weather in May. Overall, while both months feature warm days with the potential for high temperatures, May tends to be wetter and cooler than September.
In comparing the weather between September and June, it's clear that both months feature warm temperatures, but with some distinct differences. September experiences a temperature range from a cool 5°C (41°F) at night to a warm 34°C (94°F) during the day, averaging around 20°C (69°F). It also has a moderate level of precipitation, totaling 77 mm (3.0 in) over 8 days, with humidity levels at 80%.
In contrast, June offers milder early morning temperatures, starting at a minimum of 10°C (51°F) and peaking at 35°C (95°F), with an average temperature of 23°C (73°F). However, June is also wetter, receiving 124 mm (4.9 in) of rainfall over 13 days and slightly higher humidity at 82%. For a closer look at what to expect, you can check Grant Park weather in June. Overall, while both months are warm, June tends to be more humid and rainy compared to the relatively drier September.
In comparing the weather of September and July, we observe distinct differences in temperature and precipitation patterns. September boasts a wider range of temperatures, with a minimum of 5°C (41°F) and an average of 20°C (69°F), while July has consistently warmer conditions, featuring a minimum of 13°C (56°F) and an average of 24°C (76°F). Both months share a maximum temperature of 34°C (94°F), but July experiences slightly more precipitation at 98 mm (3.9 in) over 12 days compared to September's 77 mm (3.0 in) over 8 days. Interestingly, both months maintain a high humidity level of 80%. For more specific details, you can check Grant Park weather in July.
In comparing the weather of September to August, we see some notable differences. September experiences a wider temperature range, with minimum temperatures dropping to 5°C (41°F) while average highs reach up to 34°C (94°F). In contrast, August maintains milder minimums at 11°C (52°F) and a slightly higher average temperature of 23°C (74°F), peaking at a maximum of 35°C (95°F). Precipitation is also marginally lower in September, totaling 77 mm (3.0 in) over about 8 days compared to August's 92 mm (3.6 in) over 11 days. Humidity levels remain fairly consistent, with September at 80% and August at 81%. For a more detailed look at August’s weather specifics, check Grant Park weather in August.
September typically offers warm temperatures with a notable range, featuring a minimum of 5°C (41°F) and a maximum of 34°C (94°F), which averages around 20°C (69°F). However, this month also sees a fair amount of precipitation, totaling 77 mm (3.0 in) over approximately 8 days, paired with high humidity levels at 80%.
In contrast, October experiences a significant drop in temperatures, with minimums plummeting down to -3°C (28°F) and an average of just 13°C (56°F), although the maximum can still reach 31°C (89°F). Rainfall is more frequent in October, totaling 135 mm (5.3 in) over 13 days, while humidity slightly increases to 82%. This transition highlights the shift from the warmth of September to the cooler, wetter conditions typical of October. For more details on what to expect, check out the Grant Park weather in October.
Comparing the weather between September and November highlights a significant shift in climate. September features a more moderate range of temperatures, with highs averaging around 20°C (69°F) and reaching up to 34°C (94°F), while November sees much colder conditions, with average temperatures plummeting to around 4°C (40°F) and lows dipping to -13°C (9°F). Although both months experience a similar number of rainy days (eight), September tends to be wetter, with precipitation levels at 77 mm (3.0 in) compared to November's 64 mm (2.5 in). Additionally, humidity levels rise slightly in November to 88%, compared to September's 80%, contributing to a much chillier atmosphere. For more details on the weather conditions in November, you can check Grant Park weather in November.
September and December present a stark contrast in weather conditions. In September, temperatures range from a minimum of 5°C (41°F) to a sizzling maximum of 34°C (94°F), with an average around 20°C (69°F). This month also experiences relatively high humidity at 80% and significant rainfall, with 77 mm (3.0 in) falling over about 8 days. In contrast, December sees much colder conditions, with temperatures dropping significantly to a minimum of -20°C (-5°F) and an average of just 1°C (34°F). The maximum temperature reaches 18°C (65°F), and while precipitation is slightly lower at 59 mm (2.3 in) over 7 days, the humidity remains high at 84%. For more insights into December weather specifically in Grant Park, visit Grant Park weather in December.
As September unfolds in Grant Park, the weather showcases a delightful transition marked by mild temperatures and refreshing breezes. With an average temperature of around 20°C (69°F), it's a perfect time for outdoor activities, though visitors should be prepared for occasional rainfall, as precipitation occurs on about 8 days of the month. Humidity levels settle around 80%, adding a gentle warmth to the air, differing from the hotter summer months yet still boasting warm touches reminiscent of the season. This combination of warmth and mildness makes September a unique month, inviting both residents and tourists to enjoy the lush landscapes. For a deeper understanding of the year-round patterns, be sure to explore Grant Park Climate.