Climate for Station: Rock is L&d 15, Illinois, United States

Loading live weather…

Station Statistics

10-Year Trend

High: +1.21 °C/decade

Low: +1.06 °C/decade

Rain: -0.67 mm/decade

25-Year Trend

High: +0.17 °C/decade

Low: -0.08 °C/decade

Rain: -0.00 mm/decade

50-Year Trend

High: +0.37 °C/decade

Low: +0.48 °C/decade

Rain: -0.05 mm/decade

All-Time Trend

High: +0.08 °C/decade

Low: +0.25 °C/decade

Rain: -0.02 mm/decade

Percentage Above-Average Days

Last 12 Months: 57.0%

This Year: 25.0%

Precipitation Concentration Index (PCI) ℹ️

Last 12 Months: 13.1

Historical Average: 13.3

Percentile Rank of Last 12 Months ℹ️

High: 88th percentile

Low: 79th percentile

Rain: 23rd percentile

Change in Variance ℹ️

High: -4.5%

Low: -6.9%

Intraday: -2.4%

Data Coverage

89.4%

First Year of Data

1871

Station Location

Weather Records

Max HighAvg HighMin HighMax AvgAvg AvgMin AvgMax LowAvg LowMin LowMax PrecipitationAvg PrecipitationMax SnowAvg Snow
Record40.6 °C-24.2 °C34.4 °C-30.8 °C29.4 °C-38.9 °C134.6 mm315.0 mm
January20.6 °C-0.7 °C-23.3 °C10.2 °C-6.0 °C-29.8 °C7.8 °C-9.5 °C-38.9 °C39.4 mm1.2 mm305.0 mm5.7 mm
February24.4 °C2.1 °C-23.3 °C14.4 °C-3.3 °C-30.8 °C9.4 °C-7.2 °C-31.4 °C98.6 mm1.3 mm315.0 mm5.2 mm
March31.1 °C8.9 °C-13.9 °C21.4 °C3.5 °C-17.4 °C16.7 °C-1.3 °C-25.6 °C134.6 mm2.1 mm152.0 mm2.0 mm
April33.9 °C16.2 °C-3.3 °C23.5 °C9.9 °C-4.5 °C21.1 °C4.8 °C-11.1 °C65.4 mm2.7 mm51.0 mm0.1 mm
May35.6 °C22.5 °C4.4 °C29.6 °C16.4 °C2.5 °C25.0 °C11.2 °C-4.4 °C81.3 mm3.4 mm0.0 mm0.0 mm
June37.8 °C27.6 °C10.0 °C31.2 °C21.7 °C11.4 °C28.9 °C16.9 °C2.2 °C95.0 mm3.5 mm0.0 mm0.0 mm
July40.0 °C29.3 °C17.8 °C34.4 °C23.7 °C15.0 °C28.9 °C19.0 °C3.3 °C131.1 mm3.1 mm0.0 mm0.0 mm
August40.6 °C28.6 °C16.4 °C33.6 °C22.6 °C12.2 °C29.4 °C18.1 °C6.1 °C81.7 mm3.1 mm0.0 mm0.0 mm
September37.7 °C24.9 °C10.0 °C29.3 °C18.3 °C6.4 °C26.1 °C13.6 °C-6.7 °C101.6 mm2.7 mm0.0 mm0.0 mm
October35.0 °C17.7 °C0.0 °C26.1 °C11.1 °C-2.3 °C22.2 °C6.7 °C-11.1 °C71.3 mm2.1 mm25.0 mm0.0 mm
November26.7 °C9.0 °C-13.9 °C20.2 °C3.7 °C-13.1 °C18.3 °C-0.2 °C-23.9 °C117.9 mm1.9 mm254.0 mm1.0 mm
December22.2 °C2.0 °C-24.2 °C17.8 °C-3.2 °C-30.1 °C13.9 °C-6.3 °C-38.3 °C95.5 mm1.5 mm152.0 mm2.5 mm

Plots

Current Year Climate Trends vs Historical

Current Year Climate Trends vs Historical - Max Temperature this Year
Current Year Climate Trends vs Historical - Min Temperature this Year
Current Year Climate Trends vs Historical - Average Temperature this Year
Current Year Climate Trends vs Historical - Rainfall this Year

Max Temperature this Year | 1 of 4

Climate 12-Month Moving Averages

Climate 12-Month Moving Averages - Max Temperature 12-Month MA
Climate 12-Month Moving Averages - Min Temperature 12-Month MA
Climate 12-Month Moving Averages - Average Temperature 12-Month MA
Climate 12-Month Moving Averages - Rainfall 12-Month MA

Max Temperature 12-Month MA | 1 of 4

Daily Average Temperatures Throughout the Year

Daily Average Temperatures Throughout the Year - Average Max Temperature Throughout Year
Daily Average Temperatures Throughout the Year - Average Min Temperature Throughout Year
Daily Average Temperatures Throughout the Year - Average Temperature Throughout Year

Average Max Temperature Throughout Year | 1 of 3

Climate ObserverClimate Observer

Monitoring climate change patterns across stations around the world.

Explore
Contact Us
Follow us
© 2026 Climate Observer. All rights reserved.