The month of October in Chicago experiences increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 36% to 46%.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Chicago, the chance of a wet day over the course of October is essentially constant, remaining around 26% throughout.
The average sliding 31-day rainfall during October in Chicago is essentially constant, remaining about 2.7 inches throughout, and rarely exceeding 4.9 inches or falling below 0.9 inches
The chance that a given day will be muggy in Chicago is decreasing during October, falling from 5% to 0% over the course of the month. For reference, on July 27, the muggiest day of the year, there are muggy conditions 50% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.
The average hourly wind speed in Chicago is increasing during October, increasing from 11.4 miles per hour to 13.0 miles per hour over the course of the month.