Statewide areal climate 1951–2025

Illinois

A 53.1°F / 40.3" normal · 2025 ran +0.7°F vs normal. 102 counties.
2026 so far · through Jul 10: This area is running +2.1°F (51.7°F) vs the 1996–2025 to-date normal — the 7th warmest start of 76 years. Precipitation 103% of normal. U.S. year-to-date →

Normal (1996–2025)

53.1°F
annual mean · 40.3" precipitation

2025 vs Normal

+0.7°F
53.8°F · 32.9" (82% of normal)

Warmest Year

55.8°F
2012 · coldest 49.6°F (1979)

Wettest Year

51.2in
1993 · driest 27.4" (1953)

Hottest Day

102.8°F
Jul 8 · 2012

Coldest Day

-20.4°F
Jan 20 · 1985

Biggest Rain Day

2.49in
Dec 3 · 1982

Record

1951–2025
75 complete years · NOAA nClimGrid

Where 2025 Ran Warm & Cool

Every county in Illinois by its 2025 temperature vs the 1996–2025 normal.
Where 2025 Ran Warm & Cool

Monthly Climate

27°
J
31°
F
42°
M
53°
A
63°
M
72°
J
76°
J
74°
A
68°
S
55°
O
43°
N
32°
D
—— normal temperature (°F) · ▮ normal precipitation (in) · 1996–2025

Counties (102)

Adams CountyAlexander CountyBond CountyBoone CountyBrown CountyBureau CountyCalhoun CountyCarroll CountyCass CountyChampaign CountyChristian CountyClark CountyClay CountyClinton CountyColes CountyCook CountyCrawford CountyCumberland CountyDe Witt CountyDeKalb CountyDouglas CountyDuPage CountyEdgar CountyEdwards CountyEffingham CountyFayette CountyFord CountyFranklin CountyFulton CountyGallatin CountyGreene CountyGrundy CountyHamilton CountyHancock CountyHardin CountyHenderson CountyHenry CountyIroquois CountyJackson CountyJasper CountyJefferson CountyJersey CountyJo Daviess CountyJohnson CountyKane CountyKankakee CountyKendall CountyKnox CountyLaSalle CountyLake CountyLawrence CountyLee CountyLivingston CountyLogan CountyMacon CountyMacoupin CountyMadison CountyMarion CountyMarshall CountyMason CountyMassac CountyMcDonough CountyMcHenry CountyMcLean CountyMenard CountyMercer CountyMonroe CountyMontgomery CountyMorgan CountyMoultrie CountyOgle CountyPeoria CountyPerry CountyPiatt CountyPike CountyPope CountyPulaski CountyPutnam CountyRandolph CountyRichland CountyRock Island CountySaline CountySangamon CountySchuyler CountyScott CountyShelby CountySt. Clair CountyStark CountyStephenson CountyTazewell CountyUnion CountyVermilion CountyWabash CountyWarren CountyWashington CountyWayne CountyWhite CountyWhiteside CountyWill CountyWilliamson CountyWinnebago CountyWoodford County
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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