Climate change in Shelby County, Illinois
Since 1979, Shelby County, Illinois has warmed 2.1°F, with about the same number of days above 90°F, 1 fewer nights above 70°F and 11% more precipitation a year. Its climate in 1996–2025 is most like Lawrence County, IL's was in 1951–1980.
- Average temperature: +2.1°F
- Summer highs (Jun–Aug): −0.1°F
- Winter lows (Dec–Feb): +3.8°F
- Precipitation: +11%
- Wettest day of the year: +39%
- Longest dry spell: −6 days
- Days above 90°F: +0 days
- Nights above 70°F: −1 days
- Freezing nights: −10 days
- Frost-free season: +8 days
- Muggy days: +5 days
- Summer heat index (Jun–Aug): +0.8°F
- Extreme fire-weather days: +8 days
- Snowfall: −34%
- Snowy days (1 inch or more): −4 days
Changes follow the trend line through every year from 1979 to 2025. Data: NOAA nClimGrid-Daily; humidity from gridMET, adjusted to airport observations.