When Do Most Car Accidents Occur in Chicago? – 2016-2020

Traffic collisions can strike even the safest and most cautious drivers. While weather can be a contributing factor in traffic collisions, accidents happen under any weather conditions. Regardless of the month, the season or weather, traffic accidents frequently occur in Chicago.

Car accidents are common in Chicago, IL. A car accident occurs roughly once every six minutes in the Windy City. Between January 1, 2016 & January, 1 2021 – 456,883 traffic collisions occurred in Chicago, IL.

During this five year time period, ten car accidents occur every hour.  Two hundred and forty accidents occurred on average per day and in this five year sample size.

This study examines the frequency of collisions in Chicago and identifies the months, seasons and how frequently slick roads and weather conditions were a contributing factor to traffic collisions during this five year period.

What Season Do Most Traffic Accidents Occur in Chicago?

While one may hypothesize that the most dangerous season to drive is in the winter, the traffic collision data outlines a different season than what may come to mind.

The Fall Season checks in with the highest volume of traffic collisions for any season during this five year period. This is partially attributed to the wet weather that the city experiences in the Fall months.

What Contributed To The Large Amounts of Traffic Accidents In Fall in Chicago?

Fall in Chicago is generally not one of the wettest times of year. In fact, October checks in as the month with the least amount of days with precipitation in a calendar year. However, during this five year time period, a higher volume of rainy days occurred than the historical average.

What Month Do Most Traffic Accidents Occur in Chicago?

Between the beginning of 2016 through the end of 2020, traffic accidents most commonly occurred in October. The second and third highest months of auto accidents were December and November.

October tends to be one of the drier months in Chicago in a calendar year historically. However in the month of October between 2016-2020, the average amounts of rainy days in this month were far higher than the normal historic trends for October*.

Between 2016 and 2020, the amount of days that experienced rain were far higher than the normal amount of rainy days in Chicago. In 2016 there were eight days of rainy weather at any point of the day, fourteen days in 2017, seventeen days in 2018, fifteen days in 2019 and fifteen days in 2020*. This amount of rainy days is higher in volume compared to the historical trends for the month of October **.

The historic average for October is eight days of rain in the month. The average amount of rainy days between 2016 to 2020 was 13.8 rainy days a month.

Source – City of Chicago
The table and data used in this report includes all traffic collisions that occurred in Chicago from 1/1/2016 – 1/1/2021. Accidents involving no injuries, injuries and fatal accidents are included in this data set.

What Time Do Most Car Accidents Occur?

The most traffic accidents occur during the afternoon commute. The hours between 2:00 PM and 5:00 PM experience the largest volumes of collisions for any time period from the beginning of 2016 through the end of 2020.

While most traffic collisions occur during the rush hour period, many of these collisions are related to an influx of vehicles on roads and many of these accidents result in minor accidents and result in minimal property damage.

The most dangerous time to drive is at nights on weekends. Although the volume of traffic accidents are lower during the late evening and early hours of the morning, this is the most common time for fatal accidents to occur. Regardless of the time of day, do not leave the scene of a car accident. “Driving away from an accident, even a minor collision, can result in a criminal, hit-and-run charge,” warn attorneys at Duncan Law Group, “if you were involved in a car accident, stay at the scene of the collision until emergency services arrive and it is appropriate for you to leave.”

What Day of the Week Are Car Accidents Most & Least Common Occur?

Between New Years Day 2016 and New Years Day 2021, the most common day for car accidents were Fridays. Daily commuters, weekend travelers and individuals venturing out to restaurants and engaging in night life contributed to the collision volume over this five year time period. The normal weekday commute traffic, compounded with weekend travel plans and night-life activities contributed to Fridays as the day with the highest amounts of traffic collisions.

The day when the fewest traffic collisions occur in Chicago are Mondays.

How Frequently is Weather a Factor in Auto Accidents?

Chicago is no stranger to weather. Known as the “Windy City”, Chicago is exposed to precipitation, frigid temperatures and snow. However, the vast majority of auto accidents happened during clear days.

Over this five year time period, traffic collisions occurred 362,891 times on clear days. Below is a breakdown of weather conditions and collisions in Chicago.

How Frequently are Wet Roads a Factor in Auto Accidents?

Wet and slick roads increase the stop time of a vehicle. When roads are slick, vehicles take longer to come to a complete stop versus a dry road.

75.4% of collisions that occurred happened on dry roads. Roads that were wet, were snowy or slushy, or had icy conditions contributed to 17.81% of all collisions between New Years 2016 and New Years Day 2021.

* If light, moderate or heavy rain or precipitation occurred during any part of the day in October, these days that experienced precipitation were included in the study
** Source for daily weather in Chicago timeanddate.com