Illinois · county areal climate 1951–2025

McHenry County, IL

A 37.0" / 48.7°F normal · 2025 ran 87% of normal precipitation.
2026 so far · through Jul 25: This area is at 108% (23.85") of the 1996–2025 to-date normal — the 20th wettest start of 76 years. Temperature +2°F vs normal. U.S. year-to-date →

Normal (1996–2025)

37.0in
annual precipitation · 48.7°F

2025 vs Normal

87%
32.0" · 49.2°F (+0.5 vs normal)

Wettest Year

48.8in
2019

Driest Year

23.8in
1956

Biggest Rain Day

3.54in
Apr 18 · 2013

Warmest Year

51.9°F
2024

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

22°
J
25°
F
36°
M
48°
A
58°
M
69°
J
72°
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.

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