Illinois · county areal climate 1951–2025

Marion County, IL

A 55.3°F / 45.2" normal · 2025 ran +1°F vs normal.
2026 so far · through Jul 9: This area is running +2.6°F (54.5°F) vs the 1996–2025 to-date normal — the 5th warmest start of 76 years. Precipitation 99% of normal. U.S. year-to-date →

Normal (1996–2025)

55.3°F
annual mean · 45.2" precipitation

2025 vs Normal

+1°F
56.3°F · 44.5" (98% of normal)

Warmest Year

57.8°F
2024 · coldest 51.6°F (1979)

Wettest Year

58.0in
1957 · driest 26.5" (1953)

Hottest Day

105.7°F
Jul 14 · 1954

Coldest Day

-19.8°F
Jan 17 · 1977

Biggest Rain Day

4.62in
Apr 5 · 2025

Record

1951–2025
75 complete years · NOAA nClimGrid

Monthly Climate

30°
J
35°
F
45°
M
55°
A
65°
M
74°
J
77°
J
75°
A
69°
S
57°
O
45°
N
35°
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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