select pnm,lnm,st_cd,st_nm,cnty_id,dm,dm_date,dm_hist,avg_tmax_data,avg_tmin_data,avg_prcp_data,rec_hi_data,rec_lo_data,avg_sndp_data,x,y,ff,lf,fd,hz,er,hz_source,kg,hzd,clim_stn_nm,hz12,hz90, feels_like_min,feels_like_max,days_of_prcp,snow,cloud_cover,humidity,wind_speed from worldtg8_pm.pm_climate_points_namer where surl = 'glen-carbon' and st_surl='illinois' and iso_cc = 'US' and prim_loc in (1,2) Glen Carbon Illinois Climate Data - Updated February 2026

Glen Carbon Illinois Climate Data

Monthly Average Climate Data for Glen Carbon Illinois

Switch Data to Celsius/Metric Units

Month	Avg. Low	Avg. High	Avg. Precip
January	23.3 °F	39.6 °F	2.67 in.
February	26.7 °F	45.0 °F	2.43 in.
March	35.4 °F	55.1 °F	3.5 in.
April	46.3 °F	66.9 °F	4.94 in.
May	57.0 °F	76.0 °F	5.25 in.
June	65.9 °F	84.8 °F	4.79 in.
July	69.7 °F	87.9 °F	4.39 in.
August	67.7 °F	86.9 °F	3.94 in.
September	59.4 °F	80.6 °F	3.17 in.
October	47.8 °F	69.0 °F	3.31 in.
November	36.6 °F	55.1 °F	3.59 in.
December	27.9 °F	44.1 °F	2.73 in.
Annual	47 °F	65.9 °F	44.71 in.

Climate Data for Glen Carbon Illinois

Average First Frost Date	Oct. 21 - Oct. 31
Average Last Frost Date	Apr. 1 - Apr. 10
Average Days With Frost	50-75 Days
Plant Hardiness Zone	Zone 7a : 0°F to 5°F
Plant Hardiness Zone - 2012	Zone 6b : -5°F to 0°F
Current Drought Conditions	Moderate Drought
Köppen Climate Classification	Dfa - Humid Continental Hot Summers With Year Around Precipitation

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