Climate change in Jefferson County, Indiana
Since 1979, Jefferson County, Indiana has warmed 3.0°F, with 1 fewer days above 90°F, 10 more nights above 70°F and 16% more precipitation a year. Its climate in 1996–2025 is most like Bullitt County, KY's was in 1951–1980.
- Average temperature: +3.0°F
- Summer highs (Jun–Aug): +0.2°F
- Winter lows (Dec–Feb): +4.8°F
- Precipitation: +16%
- Wettest day of the year: +12%
- Longest dry spell: +0 days
- Days above 90°F: −1 days
- Nights above 70°F: +10 days
- Freezing nights: −25 days
- Frost-free season: +16 days
- Muggy days: +6 days
- Summer heat index (Jun–Aug): +0.4°F
- Extreme fire-weather days: +11 days
Changes follow the trend line through every year from 1979 to 2025. Data: NOAA nClimGrid-Daily; humidity from gridMET, adjusted to airport observations.