October weather forecast
Illinois, USA

October in Illinois is a celebration of autumn, with temperatures continuing their downward trajectory and the state's foliage reaching its peak vibrancy. In the northern territories close to Wisconsin, daytime temperatures often linger in the upper 50s°F to mid-60s°F. Meanwhile, the southern parts, adjacent to Kentucky, display a bit more warmth, fluctuating between the mid to upper 60s°F.

Chicago, with its architectural grandeur, becomes a visual feast as the trees, set against the backdrop of towering skyscrapers, burst into a riot of reds, yellows, and oranges. The influence of Lake Michigan is felt more keenly as the cold breezes set in, hinting at the winter to come. Outdoor events and activities in the city take on a festive aura, with pumpkin patches and harvest festivals setting the tone.

Night temperatures in October are notably cooler, often resting in the mid to upper 40s°F range. These chilly nights, accompanied by shorter days, are harbingers of the winter looming on the horizon.

When juxtaposed with September, October's transition into deeper autumn is unmistakable. The frequency of rainfall diminishes, but when it occurs, it often takes the form of drizzles or light showers. By the time October draws to a close, the state braces for the colder embrace of November and the impending winter chill.

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• Chicago - October »
  With an average relative humidity of 73%, October is the least humid month in Chicago, Illinois. In Chicago, during October, the rain falls for 14.2 days and regularly aggregates up to 3.11" (79mm) of precipitation.
• Aurora - October »
  In Aurora, during October, the rain falls for 9.2 days and regularly aggregates up to 0.98" (25mm) of precipitation. October is the least humid month in Aurora with an average relative humidity of 74%.
• Rockford - October »
  In Rockford, in October, during 12.9 rainfall days, 2.56" (65mm) of precipitation is typically accumulated. In Rockford, in October, it is raining for 12.9 days, with typically 2.56" (65mm) of accumulated precipitation.
• Joliet - October »
  In October, in Joliet, Illinois, the rain falls for 12.9 days. On the first day of October in Joliet, sunrise is at 6:49 am and sunset at 6:33 pm.
• Naperville - October »
  In Naperville in October, during 11 rainfall days, 1.42" (36mm) of precipitation is typically accumulated. In Naperville, during October, the rain falls for 11 days and regularly aggregates up to 1.42" (36mm) of precipitation.
• Springfield - October »
  October is the least humid month in Springfield with an average relative humidity of 70%. In Springfield in October, it is raining for 10.3 days, with typically 2.01" (51mm) of accumulated precipitation.
• Peoria - October »
  With an average relative humidity of 71%, October is the least humid month in Peoria. In Peoria, in October, it is raining for 10.3 days, with typically 1.46" (37mm) of accumulated precipitation.
• Elgin - October »
  In Elgin during October, the rain falls for 13.3 days and regularly aggregates up to 2.01" (51mm) of precipitation. In Elgin, Illinois, in October, it is raining for 13.3 days, with typically 2.01" (51mm) of accumulated precipitation.
• Waukegan - October »
  In Waukegan, Illinois, in October, it is raining for 12.9 days, with typically 1.89" (48mm) of accumulated precipitation. In Waukegan, in October, during 12.9 rainfall days, 1.89" (48mm) of precipitation is typically accumulated.
• Champaign - October »
  In Champaign snow does not fall in May through October. With an average relative humidity of 70%, October is the least humid month in Champaign.
• Cicero - October »
  In Cicero, during October, the rain falls for 10.2 days and regularly aggregates up to 0.98" (25mm) of precipitation. On the first day of October in Cicero, sunrise is at 6:48 am and sunset at 6:32 pm.
• Bloomington - October »
  In Bloomington, during October, the rain falls for 10.8 days and regularly aggregates up to 1.89" (48mm) of precipitation. On the last day of October, in Bloomington, sunrise is at 7:25 am and sunset at 5:53 pm CDT.