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 = 'mount-sterling' and st_surl='illinois' and iso_cc = 'US' and prim_loc in (1,2) Mount Sterling Illinois Climate Data - Updated February 2026

Mount Sterling Illinois Climate Data

Monthly Average Climate Data for Mount Sterling Illinois

Switch Data to Celsius/Metric Units

Month	Avg. Low	Avg. High	Avg. Precip
January	17.3 °F	34.3 °F	1.92 in.
February	21.0 °F	39.3 °F	1.97 in.
March	30.3 °F	50.9 °F	2.51 in.
April	41.1 °F	63.0 °F	3.98 in.
May	52.7 °F	72.8 °F	5.11 in.
June	61.9 °F	81.6 °F	4.64 in.
July	65.4 °F	85.2 °F	3.67 in.
August	63.2 °F	83.9 °F	3.56 in.
September	54.2 °F	78.0 °F	3.53 in.
October	43.0 °F	65.6 °F	3.24 in.
November	32.2 °F	51.7 °F	2.73 in.
December	22.7 °F	39.2 °F	2.1 in.
Annual	42.1 °F	62.1 °F	38.96 in.

Climate Data for Mount Sterling Illinois

Average First Frost Date	Oct. 21 - Oct. 31
Average Last Frost Date	Apr. 11 - Apr. 20
Average Days With Frost	75-100 Days
Plant Hardiness Zone	Zone 6a : -10°F to -5°F
Plant Hardiness Zone - 2012	Zone 5b : -15°F to -10°F
Current Drought Conditions	Moderate Drought
Köppen Climate Classification	Dfa - Humid Continental Hot Summers With Year Around Precipitation

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