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Chicago, IL vs Decatur, IN weather comparison

Chicago

IL

Chicago and Decatur have remarkably similar climates.

The year at a glance

Averages from 30 years of climate history, 1991-2020

Annual weather statistics for Chicago, IL and Decatur, IN
ChicagoMetricDecatur
180 daysSunny daysclear or partly cloudy skies175 days
39 inPrecipitationper year39 in
132 daysWet daysrain or snow per year133 days
37 inSnowfallper year28 in
16 daysHot daysabove 90 °F17 days
102 daysFreezing nightsat or below 32 °F126 days
71%Humidityaverage relative70%
52 °FAverage temperatureyear round51 °F

Monthly temperatures

Average daily high and low for each month, in °F. The gap between the two lines is what an ordinary day feels like across the year.

ChicagoDecatur

Daily highs

406080JanMarMayJulSepNovChicago, Jan: 32 °FChicago, Feb: 36 °FChicago, Mar: 46 °FChicago, Apr: 57 °FChicago, May: 68 °FChicago, Jun: 78 °FChicago, Jul: 83 °FChicago, Aug: 81 °FChicago, Sep: 75 °FChicago, Oct: 62 °FChicago, Nov: 49 °FChicago, Dec: 37 °FDecatur, Jan: 33 °FDecatur, Feb: 36 °FDecatur, Mar: 47 °FDecatur, Apr: 60 °FDecatur, May: 72 °FDecatur, Jun: 81 °FDecatur, Jul: 84 °FDecatur, Aug: 82 °FDecatur, Sep: 77 °FDecatur, Oct: 64 °FDecatur, Nov: 50 °FDecatur, Dec: 38 °F

Daily lows

204060JanMarMayJulSepNovChicago, Jan: 20 °FChicago, Feb: 23 °FChicago, Mar: 31 °FChicago, Apr: 41 °FChicago, May: 51 °FChicago, Jun: 61 °FChicago, Jul: 67 °FChicago, Aug: 67 °FChicago, Sep: 60 °FChicago, Oct: 47 °FChicago, Nov: 36 °FChicago, Dec: 25 °FDecatur, Jan: 18 °FDecatur, Feb: 20 °FDecatur, Mar: 29 °FDecatur, Apr: 39 °FDecatur, May: 50 °FDecatur, Jun: 60 °FDecatur, Jul: 63 °FDecatur, Aug: 60 °FDecatur, Sep: 53 °FDecatur, Oct: 42 °FDecatur, Nov: 33 °FDecatur, Dec: 24 °F
View monthly temperatures as a table
Monthly temperatures (°F)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Chicago high323646576878838175624937
Decatur high333647607281848277645038
Chicago low202331415161676760473625
Decatur low182029395060636053423324

Monthly precipitation

Total rain plus melted snow for each month, in inches. Taller bars mean wetter months.

ChicagoDecatur
0.02.04.0JanMarMayJulSepNovChicago, Jan: 2.4 inChicago, Feb: 2.1 inChicago, Mar: 2.8 inChicago, Apr: 4.5 inChicago, May: 4.4 inChicago, Jun: 4.0 inChicago, Jul: 3.6 inChicago, Aug: 3.8 inChicago, Sep: 3.0 inChicago, Oct: 3.3 inChicago, Nov: 2.8 inChicago, Dec: 2.4 inDecatur, Jan: 2.8 inDecatur, Feb: 2.4 inDecatur, Mar: 3.3 inDecatur, Apr: 4.1 inDecatur, May: 4.1 inDecatur, Jun: 3.9 inDecatur, Jul: 3.5 inDecatur, Aug: 3.3 inDecatur, Sep: 2.5 inDecatur, Oct: 2.9 inDecatur, Nov: 3.1 inDecatur, Dec: 2.8 in
View monthly precipitation as a table
Monthly precipitation (inches)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Chicago2.42.12.84.54.44.03.63.83.03.32.82.4
Decatur2.82.43.34.14.13.93.53.32.52.93.12.8

Monthly sunny days

Days each month with clear or partly cloudy skies, so compare the same month between cities.

ChicagoDecatur
01020JanMarMayJulSepNovChicago, Jan: 10 daysChicago, Feb: 11 daysChicago, Mar: 14 daysChicago, Apr: 13 daysChicago, May: 15 daysChicago, Jun: 16 daysChicago, Jul: 20 daysChicago, Aug: 20 daysChicago, Sep: 20 daysChicago, Oct: 16 daysChicago, Nov: 14 daysChicago, Dec: 11 daysDecatur, Jan: 10 daysDecatur, Feb: 10 daysDecatur, Mar: 13 daysDecatur, Apr: 13 daysDecatur, May: 15 daysDecatur, Jun: 17 daysDecatur, Jul: 20 daysDecatur, Aug: 20 daysDecatur, Sep: 20 daysDecatur, Oct: 16 daysDecatur, Nov: 13 daysDecatur, Dec: 10 days
View monthly sunny days as a table
Monthly sunny days (days)
CityJanFebMarAprMayJunJulAugSepOctNovDec
Chicago101114131516202020161411
Decatur101013131517202020161310

Keep comparing

Nearby cities and popular picks for each side of this matchup. Any two cities can be compared from the home page.

About this data

Every figure on this page is a 30 year average computed from daily climate history for 1991-2020, using each city's own coordinates. Wet days count days with measurable precipitation, calibrated against the wet day counts in NOAA's published climate normals. Sunny days count clear plus partly cloudy days, defined as average cloud cover of 63 percent or less and calibrated against NOAA's published sky cover tables. Snowfall figures are model estimates anchored to NOAA station measurements near each city.

Weather data by Open-Meteo.com (CC BY 4.0). Contains modified Copernicus Climate Change Service information (ERA5, ERA5-Land).