Illinois · county areal climate 1951–2025
Mercer County, IL
A 51.0°F / 37.1" normal · 2025 ran +1.2°F vs normal.
2026 so far · through Jul 9: This area is running
+2.6°F (49.7°F) vs the 1996–2025 to-date normal — the
5th warmest start of 76 years. Precipitation
100% of normal.
U.S. year-to-date → Normal (1996–2025)
51.0°F
annual mean · 37.1" precipitation
2025 vs Normal
+1.2°F
52.2°F · 32.1" (87% of normal)
Warmest Year
53.8°F
2024 · coldest 47.2°F (2014)
Wettest Year
53.0in
2009 · driest 22.0" (1988)
Hottest Day
102.0°F
Jul 24 · 2012
Coldest Day
-26.9°F
Jan 31 · 2019
Biggest Rain Day
3.7in
Sep 13 · 2008
Record
1951–2025
75 complete years · NOAA nClimGrid
—— normal temperature (°F) · ▮ normal precipitation (in) · 1996–2025
Areal
nClimGrid averages (NOAA/NCEI) over the whole area — an average across the region, not a single station. Separate from the
station records.