Station information
- Integrated Surface Dataset (ISD) station ID: 997338
- Country: US
- State: IL
- Latitude: 42.0
- Longitude: -87.5
High Temperatures
On July 31 in CHICAGO the average high temperature is 78.2 °F (25.7 °C). The lowest recored high temperature was 69.3 °F (20.7 °C) in 2013 and the highest recored high temperature was 88.0 °F (31.1 °C) in 2024. The high temperature is usually* between 74.9 °F (23.8 °C) and 81.5 °F (27.5 °C). About a quarter of the time, the high temperature is less than 74.9 °F (23.8 °C), and another quarter of the time, the high temperature is greater than and 81.5 °F (27.5 °C). About 95% of the time, the high temperature has been between 68.5 °F (20.3 °C) and 87.9 °F (31.0 °C).
Low Temperatures
On July 31 in CHICAGO the average low temperature is 71.0 °F (21.7 °C). The lowest recored low temperature was 63.7 °F (17.6 °C) in 2014 and the lowest recored low temperature was 76.1 °F (24.5 °C) in 2024. The low temperature is usually* between 68.5 °F (20.3 °C) and 73.5 °F (23.1 °C). About a quarter of the time, the low temperature is less than 68.5 °F (20.3 °C), and another quarter of the time, the low temperature is greater than and 73.5 °F (23.1 °C). About 95% of the time, the low temperature has been between 63.7 °F (17.6 °C) and 78.3 °F (25.7 °C).
Frost
On July 31 in CHICAGO expect the temperatures to drop below freezing for a risk of frost about 0.0% of the time.
Data Source(s)
The data used to compute the average high/low temperatures for this location were taken from the following stations:
- CHICAGO — Integrated Surface Dataset (ISD) station ID: 997338 — from year 2005 to 2025