Illinois · county areal climate 1951–2025

Boone County, IL

A 48.7°F / 37.1" normal · 2025 ran +0.9°F vs normal.
2026 so far · through Jul 10: This area is running +2.1°F (46.8°F) vs the 1996–2025 to-date normal — the 7th warmest start of 76 years. Precipitation 116% of normal. U.S. year-to-date →

Normal (1996–2025)

48.7°F
annual mean · 37.1" precipitation

2025 vs Normal

+0.9°F
49.6°F · 33.4" (90% of normal)

Warmest Year

52.0°F
2024 · coldest 44.6°F (2014)

Wettest Year

49.2in
1972 · driest 23.9" (1958)

Hottest Day

101.8°F
Jul 7 · 2012

Coldest Day

-27.9°F
Jan 31 · 2019

Biggest Rain Day

3.56in
Sep 14 · 1961

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

21°
J
25°
F
36°
M
48°
A
59°
M
69°
J
73°
J
71°
A
64°
S
52°
O
39°
N
27°
D
—— 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.

Nearby

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