Illinois · county areal climate 1951–2025

Grundy County, IL

A 37.0" / 51.2°F normal · 2025 ran 83% of normal precipitation.
2026 so far · through Jul 25: This area is at 110% (24.45") of the 1996–2025 to-date normal — the 19th wettest start of 76 years. Temperature +1.8°F vs normal. U.S. year-to-date →

Normal (1996–2025)

37.0in
annual precipitation · 51.2°F

2025 vs Normal

83%
30.8" · 52.0°F (+0.8 vs normal)

Wettest Year

51.9in
2019

Driest Year

22.2in
1963

Biggest Rain Day

4.45in
Jun 26 · 1978

Warmest Year

54.4°F
2012

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

24°
J
28°
F
40°
M
50°
A
62°
M
71°
J
74°
J
72°
A
66°
S
54°
O
41°
N
30°
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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