- Latitude: 42.0
- Longitude: -87.5
High Temperatures
On August 21 in this location the average high temperature is 80.5 °F (27.0 °C). The lowest recored high temperature was 69.1 °F (20.6 °C) in 1985 and the highest recored high temperature was 98.1 °F (36.7 °C) in 1955. The high temperature is usually* between 76.1 °F (24.5 °C) and 85.0 °F (29.4 °C). About a quarter of the time, the high temperature is less than 76.1 °F (24.5 °C), and another quarter of the time, the high temperature is greater than and 85.0 °F (29.4 °C). About 95% of the time, the high temperature has been between 67.5 °F (19.7 °C) and 93.5 °F (34.2 °C).
Low Temperatures
On August 21 in this location the average low temperature is 66.2 °F (19.0 °C). The lowest recored low temperature was 46.0 °F (7.8 °C) in 1950 and the lowest recored low temperature was 81.0 °F (27.2 °C) in 1968. The low temperature is usually* between 62.2 °F (16.8 °C) and 70.2 °F (21.2 °C). About a quarter of the time, the low temperature is less than 62.2 °F (16.8 °C), and another quarter of the time, the low temperature is greater than and 70.2 °F (21.2 °C). About 95% of the time, the low temperature has been between 54.6 °F (12.6 °C) and 77.8 °F (25.4 °C).
Frost
On August 21 in this location 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:
- NORTHERLY ISLAND — Integrated Surface Dataset (ISD) station ID: 998499 — from year 2012 to 2025
- CHICAGO — Integrated Surface Dataset (ISD) station ID: 997338 — from year 2005 to 2024
- FOSTER AVE CHICAGO — Integrated Surface Dataset (ISD) station ID: 998497 — from year 2012 to 2019
- 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
- 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 1988 to 1990
- 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