Station information
- Integrated Surface Dataset (ISD) station ID: 997338
- Country: US
- State: IL
- Latitude: 42.0
- Longitude: -87.5
High Temperatures
On August 12 in CHICAGO the average high temperature is 77.9 °F (25.5 °C). The lowest recored high temperature was 70.3 °F (21.3 °C) in 2017 and the highest recored high temperature was 91.8 °F (33.2 °C) in 2025. The high temperature is usually* between 74.0 °F (23.3 °C) and 81.8 °F (27.7 °C). About a quarter of the time, the high temperature is less than 74.0 °F (23.3 °C), and another quarter of the time, the high temperature is greater than and 81.8 °F (27.7 °C). About 95% of the time, the high temperature has been between 66.6 °F (19.2 °C) and 89.3 °F (31.8 °C).
Low Temperatures
On August 12 in CHICAGO the average low temperature is 70.0 °F (21.1 °C). The lowest recored low temperature was 61.2 °F (16.2 °C) in 2014 and the lowest recored low temperature was 78.6 °F (25.9 °C) in 2025. The low temperature is usually* between 66.9 °F (19.4 °C) and 73.1 °F (22.8 °C). About a quarter of the time, the low temperature is less than 66.9 °F (19.4 °C), and another quarter of the time, the low temperature is greater than and 73.1 °F (22.8 °C). About 95% of the time, the low temperature has been between 61.0 °F (16.1 °C) and 78.9 °F (26.1 °C).
Frost
On August 12 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