Illinois · county areal climate 1951–2025

DeKalb County, IL

A 36.9" / 49.3°F normal · 2025 ran 83% of normal precipitation.
2026 so far · through Jul 25: This area is at 98% (21.68") of the 1996–2025 to-date normal — the 42nd driest start of 76 years. Temperature +2°F vs normal. U.S. year-to-date →

Normal (1996–2025)

36.9in
annual precipitation · 49.3°F

2025 vs Normal

83%
30.7" · 50.3°F (+1 vs normal)

Wettest Year

48.9in
1972

Driest Year

22.7in
2005

Biggest Rain Day

5.71in
Jul 18 · 1996

Warmest Year

52.4°F
2024

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

22°
J
26°
F
37°
M
49°
A
60°
M
69°
J
73°
J
71°
A
65°
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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