Illinois · county areal climate 1951–2025

Johnson County, IL

A 49.8" / 57.3°F normal · 2025 ran 95% of normal precipitation.
2026 so far · through Jul 25: This area is at 75% (23.17") of the 1996–2025 to-date normal — the 15th driest start of 76 years. Temperature +1.7°F vs normal. U.S. year-to-date →

Normal (1996–2025)

49.8in
annual precipitation · 57.3°F

2025 vs Normal

95%
47.4" · 57.5°F (+0.2 vs normal)

Wettest Year

70.9in
2011

Driest Year

31.2in
1953

Biggest Rain Day

5.65in
Mar 19 · 2008

Warmest Year

60.0°F
2012

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

34°
J
38°
F
48°
M
57°
A
67°
M
75°
J
78°
J
77°
A
70°
S
59°
O
47°
N
38°
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.

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