- Country: US
- State: IL
- Latitude: 41.856
- Longitude: -87.609
High Temperatures
On October 21 in NORTHERLY ISLAND the average high temperature is 66.7 °F (19.3 °C). The lowest recored high temperature was 52.9 °F (11.6 °C) in 2016 and the highest recored high temperature was 80.6 °F (27.0 °C) in 2024. The high temperature is usually* between 60.2 °F (15.7 °C) and 73.1 °F (22.8 °C). About a quarter of the time, the high temperature is less than 60.2 °F (15.7 °C), and another quarter of the time, the high temperature is greater than and 73.1 °F (22.8 °C). About 95% of the time, the high temperature has been between 47.8 °F (8.8 °C) and 85.5 °F (29.7 °C).
Low Temperatures
On October 21 in NORTHERLY ISLAND the average low temperature is 47.6 °F (8.7 °C). The lowest recored low temperature was 35.1 °F (1.7 °C) in 2022 and the lowest recored low temperature was 57.9 °F (14.4 °C) in 2017. The low temperature is usually* between 43.6 °F (6.5 °C) and 51.5 °F (10.9 °C). About a quarter of the time, the low temperature is less than 43.6 °F (6.5 °C), and another quarter of the time, the low temperature is greater than and 51.5 °F (10.9 °C). About 95% of the time, the low temperature has been between 36.1 °F (2.3 °C) and 59.1 °F (15.0 °C).
Frost
On October 21 in NORTHERLY ISLAND expect the temperatures to drop below freezing for a risk of frost about 0.4% 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 2024