High Temperatures
On September 12 in Chicago, IL (Illinois), USA the average high temperature is 77.3 °F (25.2 °C). The lowest recored high temperature was 55.9 °F (13.3 °C) in 2014 and the highest recored high temperature was 95.0 °F (35.0 °C) in 1952. The high temperature is usually* between 71.9 °F (22.2 °C) and 82.7 °F (28.2 °C). About a quarter of the time, the high temperature is less than 71.9 °F (22.2 °C), and another quarter of the time, the high temperature is greater than and 82.7 °F (28.2 °C). About 95% of the time, the high temperature has been between 61.7 °F (16.5 °C) and 93.0 °F (33.9 °C).
Low Temperatures
On September 12 in Chicago, IL (Illinois), USA the average low temperature is 59.3 °F (15.2 °C). The lowest recored low temperature was 38.3 °F (3.5 °C) in 1964 and the lowest recored low temperature was 74.1 °F (23.4 °C) in 2021. The low temperature is usually* between 54.4 °F (12.4 °C) and 64.3 °F (18.0 °C). About a quarter of the time, the low temperature is less than 54.4 °F (12.4 °C), and another quarter of the time, the low temperature is greater than and 64.3 °F (18.0 °C). About 95% of the time, the low temperature has been between 44.9 °F (7.2 °C) and 73.8 °F (23.2 °C).
Frost
On September 12 in Chicago, IL (Illinois), USA 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 O'HARE INTERNATIONAL — Integrated Surface Dataset (ISD) station ID: 725300 — Weather Bureau Army Navy (WBAN): 94846 — from year 1947 to 2024
- CHICAGO — Integrated Surface Dataset (ISD) station ID: 997338 — from year 2005 to 2024
- CHICAGO MIDWAY INTL ARPT — Integrated Surface Dataset (ISD) station ID: 725340 — Weather Bureau Army Navy (WBAN): 14819 — from year 1973 to 2024
- GARY/CHICAGO AIRPORT — Integrated Surface Dataset (ISD) station ID: 725337 — Weather Bureau Army Navy (WBAN): 04807 — from year 2006 to 2024
- 9087044 - CALUMET IL — Integrated Surface Dataset (ISD) station ID: 997255 — from year 2006 to 2024
- NORTHERLY ISLAND — Integrated Surface Dataset (ISD) station ID: 998499 — from year 2012 to 2024
- FOSTER AVE CHICAGO — Integrated Surface Dataset (ISD) station ID: 998497 — from year 2012 to 2017
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— Integrated Surface Dataset (ISD) station ID: 725337 — from year 1981 to 2005 - CHICAGO/MEIGS — Integrated Surface Dataset (ISD) station ID: 725346 — from year 2000 to 2002
- CHICAGO/MEIGS — Integrated Surface Dataset (ISD) station ID: 725346 — Weather Bureau Army Navy (WBAN): 94866 — from year 1973 to 1999
- WILMETTE (MARINES)& — Integrated Surface Dataset (ISD) station ID: 725307 — from year 1976 to 1995
- CHICAGO / CALUMET COAST GUARD — Integrated Surface Dataset (ISD) station ID: 725344 — from year 1994 to 1995
- NAVAL AIR STATION — Integrated Surface Dataset (ISD) station ID: 725306 — Weather Bureau Army Navy (WBAN): 14855 — from year 1973 to 1994
- WILMETTE (CGS) — Integrated Surface Dataset (ISD) station ID: 722417 — from year 1987 to 1990
- CALUMET (CGS) — Integrated Surface Dataset (ISD) station ID: 722418 — from year 1987 to 1988
- CHICAGO MIDWAY AP — Weather Bureau Army Navy (WBAN): 14819 — from year 1948 to 1972
- CHICAGO OHARE INTL AP — Weather Bureau Army Navy (WBAN): 94846 — from year 1970 to 1972
- NAVAL AIR STATION — Weather Bureau Army Navy (WBAN): 14855 — from year 1945 to 1972
- CHICAGO MEIGS FIELD — Weather Bureau Army Navy (WBAN): 94866 — from year 1966 to 1969
- PARK RIDGE AF — Weather Bureau Army Navy (WBAN): 14810 — from year 1949 to 1958