Last updated: February 24, 2025
October in Chicago presents a dynamic transition into fall, with temperatures ranging from a comfortable maximum of 29°C (or 85°F) to a chilly minimum of -1°C (31°F). The average temperature settles at a brisk 13°C (55°F), inviting layers and cozy outings. With precipitation measuring at 142 mm (5.6 inches) over 13 days, it's essential to keep an umbrella handy amid the 82% humidity that adds a distinctive chill to the air. This month offers Chicagoans and visitors alike a captivating blend of late warmth and early autumn chill.
As October arrives in Chicago, the city begins to experience a shift in temperatures that heralds the onset of fall. With averages around 13°C (55°F), the month offers a refreshing respite from the summer heat, showing a marked decrease in daytime highs to a pleasant max of 29°C (85°F). The chill of early mornings is felt with minimums dipping to -1°C (31°F), hinting at the colder months ahead. This transitional period not only signifies the end of summer’s warmth but also showcases a vibrant tapestry of autumn colors, making October a beautiful yet brisk month in the Windy City. As the average temperatures continue to decline, Chicagoans relish the last glimpses of warmth before winter's grip kicks in.
In October, Chicago experiences a notable uptick in precipitation, with an average of 142 mm (5.6 in) falling over 13 days. This increase marks a distinct contrast to the drier September, where only 78 mm (3.1 in) was recorded across 9 days. The transition into autumn brings a shift in the weather pattern, as October's rainfall contributes to the city's overall moisture levels, which are typically at their highest since spring. This trend highlights the onset of wetter weather as the year progresses, paving the way for the cooler months ahead and making October an essential month in Chicago's annual precipitation cycle.
October in Chicago brings a slight shift in humidity levels, maintaining a comfortable 82% that mirrors the preceding months. Following the summer's warmer days, which saw humidity levels hover around 80%, October's moisture contributes to the crispness in the air as fall settles in. This month reflects a broader trend of fluctuating humidity across the seasons, peaking in the spring with 85% and dipping to a more manageable 79% in May. As the city transitions into winter, November sees a notable rise to 88%, highlighting the unique challenge of Chicago's climate—a rhythmic dance between warmth and chill, with humidity levels playing a significant role throughout the year.
As October rolls into Chicago, the UV Index settles at a moderate 6, indicating a high exposure category with a burn time of 25 minutes. This marks a notable decline from the peak summer months, where indices soared to 10 in July and June, reflecting the heightened sun intensity. Earlier in the year, Chicagoans experienced a gradual rise from January’s moderate 3 to a striking 9 in May, before the summer's blistering heat. Now, as autumn approaches, the UV radiation wanes, yet it’s still essential to stay vigilant with sun protection during those sunny fall days. For more information about UV exposure in the Windy City, check out Chicago UV Index.
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October in Chicago brings a delightful transition as summer's warmth begins to retreat, offering 228 hours of sunshine. This month marks a noticeable dip from the bustling peak of July, which boasts an impressive 362 hours. As autumn unfolds, sunlight gradually fades, yet October still offers a generous amount, standing out against the colder and cloudier months that follow. Compared to the bright days of September's 288 hours, October invites residents to savor the crisp air and vibrant fall colors, making it a splendid time for outdoor activities before winter sets in. The steady decline in sunshine from the summer highs serves as a gentle reminder of the changing seasons, leaving Chicagoans eager for cozy evenings and warm drinks as they prepare for the chill ahead.
In October, Chicago experiences a 33% chance of sunny weather, a figure that reflects a typical transition into fall. This month generally sees a decline in sunshine compared to the late summer months, where August peaks at a sun-washed 47%. Interestingly, as the city shifts from the vibrancy of September—boasting a 56% chance of sun—October's forecast indicates a noticeable dip, aligning closely with other autumn months like November at 44% and December at 35%. Despite this decrease, October often delights with crisp, sunny days amidst the array of colorful foliage, making it a charming, albeit unpredictable time in the Windy City.
As autumn settles in Chicago, October brings a gentle decline in daylight, with approximately 11 hours illuminating the city each day. This month reflects a notable shift from the sun-drenched days of summer, peaking in June with 15 hours of daylight, as the city transitions through a gradual reduction in light hours. Following the peak, daylight ebbs, mirroring nature's rhythm as leaves change and fall. After enjoying 14 hours in May and 12 hours in September, October’s daylight is a reminder of the shifting seasons, providing a cozy backdrop as neighborhoods prepare for the chill of winter. While daylight dwindles, the vibrant hues of fall foliage brighten the days, inviting Chicagoans to revel in the beauty of this transitional month.
As October unfolds in Chicago, the average wind speed settles at 4.0 m/s (9 mph), reflecting a slight decline from the breezier September, which boasted 4.1 m/s (9 mph). This month marks a transition as the city transitions from the warm embrace of summer into the crispness of autumn. Interestingly, while October's winds are gentler than earlier in the year, they still hold their own against the winter winds that start to creep in, foreshadowing November's stronger 4.8 m/s (11 mph) gusts. Overall, the trend showcases a cyclical pattern where early autumn winds provide a refreshing chill, contrasting with the more vigorous winds expected in the coming months.
The weather in Chicago changes throughout the year, offering a unique experience in each season. Below is a month-by-month comparison of October's weather with other months, highlighting differences in temperature, precipitation, and other key factors. Click on each section to discover seasonal trends in Chicago and find detailed weather information for every month.
October and January exhibit stark contrasts in weather. October experiences a wider temperature range, with averages around 13°C (55°F) and maximums reaching up to 29°C (85°F), creating a pleasant and mild atmosphere. In contrast, January is characterized by much colder temperatures, averaging -3°C (27°F) and plunging as low as -29°C (-21°F). While October is noticeably wetter, with 142 mm (5.6 in) of precipitation over 13 days, January sees significantly less rain, totaling 68 mm (2.7 in) over just 9 days. Interestingly, both months share the same humidity level of 82%, highlighting a damp chill in January compared to the more temperate October days. For more details, check out Chicago weather in January.
October and February present stark contrasts in weather. October enjoys milder temperatures, ranging from a chilly minimum of -1°C (31°F) to a warm maximum of 29°C (85°F), with an average of 13°C (55°F). In contrast, February is significantly colder, with temperatures plummeting to -30°C (-22°F) at night and only reaching a daytime high of 18°C (64°F), averaging -2°C (29°F). While October experiences more precipitation at 142 mm (5.6 in) over 13 days, February has less overall precipitation at 70 mm (2.7 in) across 12 days. Both months showcase high humidity levels, around 82% in October and 83% in February, but the biting cold of February gives it a distinct character. For more information, you can visit Chicago weather in February.
October and March present contrasting weather patterns, each with distinctive characteristics. In October, temperatures range from a minimum of -1°C (31°F) to a warm average of 13°C (55°F), with maximums reaching up to 29°C (85°F). The month is relatively wet, experiencing about 142 mm (5.6 in) of precipitation over approximately 13 days, combined with a humidity level of 82%. In contrast, March features cooler conditions, with temperatures dipping as low as -18°C (-1°F) and averaging around 4°C (39°F), while peaks can reach 23°C (74°F). This month sees less rainfall, totaling around 95 mm (3.7 in) over 11 days and a slightly higher humidity of 84%. For more detailed information on March weather, you can visit Chicago weather in March.
When comparing the weather in October and April, notable differences surface in temperature and precipitation patterns. October generally enjoys milder temperatures, with an average of 13°C (55°F) and highs reaching up to 29°C (85°F), while April averages lower at 8°C (47°F) and peaks at 26°C (79°F). Precipitation levels are relatively similar, with October receiving 142 mm (5.6 in) over 13 days and April slightly less at 125 mm (4.9 in) across the same number of days. Humidity is comparable, hovering at 82% in October and 85% in April, contributing to the overall coolness of these transitional months. For more insights into April's climate specifics, check out Chicago weather in April.
In October, temperatures can vary significantly, with a minimum of -1°C (31°F) and an average high of 29°C (85°F), while May offers a somewhat milder climate with a minimum of -1°C (31°F) and a higher average temperature of 15°C (59°F), peaking at 32°C (90°F). Both months experience considerable precipitation, with October receiving 142 mm (5.6 in) over 13 days and May having slightly more at 156 mm (6.1 in) across 15 days. Humidity levels are fairly similar, with October at 82% and May slightly lower at 79%. For those interested in a deeper dive into May's weather patterns, you can visit Chicago weather in May.
In contrast to the milder, more variable temperatures of October, which range from a chilly -1°C (31°F) to a warm 29°C (85°F), June presents a significantly warmer climate, with temperatures fluctuating between a minimum of 10°C (50°F) and a maximum of 33°C (91°F). Both months experience similar levels of precipitation, around 144 mm (5.7 in) in June and 142 mm (5.6 in) in October, with rainfall occurring on approximately 13 days in each month. Notably, humidity levels remain consistent at 82%, contributing to a muggy feel in June, while the crispness of October can offer a refreshing contrast. For more insights on Chicago's weather in June, you can check Chicago weather in June.
When comparing the weather in October to that of July, a clear contrast emerges in both temperature and precipitation. October experiences a wider range of temperatures, with lows dipping to -1°C (31°F) and highs reaching up to 29°C (85°F). In contrast, July is consistently warmer, with average temperatures ranging from a minimum of 14°C (58°F) to a maximum of 33°C (92°F). Precipitation levels also vary; while October receives 142 mm (5.6 in) over 13 days, July has a slightly lower total of 104 mm (4.1 in) across 12 days. Additionally, October has a moderate humidity level of 82%, compared to July's slightly lower 80%. For more details on the weather specifically in July, you can visit Chicago weather in July.
In October, temperatures exhibit a notable shift compared to August, with a minimum of -1°C (31°F) and maximum reaching 29°C (85°F), while the average temperature settles around 13°C (55°F). This contrasts with August, where the temperatures range from a minimum of 11°C (53°F) to a maximum of 33°C (92°F), with an average of 23°C (73°F). Additionally, October is wetter, experiencing 142 mm (5.6 in) of precipitation over 13 days, compared to August's 84 mm (3.3 in) over just 11 days. Humidity levels remain relatively similar, with October at 82% and August at 81%. For more details, check out Chicago weather in August.
In comparing the weather of October and September, October experiences a broader temperature range with minimums dropping to -1°C (31°F) and maximums reaching up to 29°C (85°F), while September maintains milder temperatures, ranging from a minimum of 6°C (42°F) to a maximum of 32°C (90°F). The average temperature for October is significantly cooler at 13°C (55°F) compared to September's warmer average of 20°C (68°F). Additionally, October sees increased precipitation, totaling 142 mm (5.6 in) over 13 days, in contrast to September's 78 mm (3.1 in) over just 9 days. Humidity levels remain relatively similar, with October at 82% and September slightly lower at 80%. For more details, check out Chicago weather in September.
October and November present a noticeable shift in weather patterns. In October, temperatures can range quite widely, with a minimum of -1°C (31°F), an average of 13°C (55°F), and a maximum reaching 29°C (85°F). The month is also marked by significant precipitation, totaling 142 mm (5.6 in) over 13 days, combined with a relative humidity of 82%. In contrast, November sees a decline in temperatures, with a minimum of -14°C (6°F) and an average of just 4°C (40°F). Although November experiences less precipitation—only 65 mm (2.6 in) over 8 days—humidity rises to 88%. For more detailed information, check out Chicago weather in November.
October and December present a stark contrast in weather conditions. In October, temperatures range from a chilly minimum of -1°C (31°F) to a warm average of 13°C (55°F), peaking at a comfortable 29°C (85°F). The month experiences significant precipitation, totaling 142 mm (5.6 in) over 13 days, with humidity levels around 82%. On the other hand, December sees much colder temperatures, with minimums dropping to -19°C (-2°F) and an average of just 1°C (34°F), while the maximums reach only 18°C (64°F). Precipitation is lower at 63 mm (2.5 in) spread over 8 days, with slightly higher humidity at 84%. For a more detailed look at December weather, you can check Chicago weather in December.
As October unfolds in Chicago, the city experiences a striking transition from the warmth of summer to the chill of approaching winter. With an average temperature that hovers around a brisk 13°C (55°F), it’s a month marked by notable variability, where sunny days can reach up to 29°C (85°F), while the nights can drop to a chilly -1°C (31°F). This blend of temperatures is complemented by frequent rainfall, averaging 142 mm (5.6 in) across 13 days, and a humidity level that sits at a notable 82%. These factors come together to create a distinctly dynamic climate that sets October apart from the more stable summer months. For a deeper understanding of how Chicago's weather evolves throughout the year, check out Chicago Climate.