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 = 'lyndon' and st_surl='illinois' and iso_cc = 'US' and prim_loc in (1,2) Lyndon Illinois Climate Data - Updated February 2026

Lyndon Illinois Climate Data

Monthly Average Climate Data for Lyndon Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January13.1 °F29.8 °F1.68 in.
February16.9 °F34.3 °F1.77 in.
March27.6 °F46.9 °F2.65 in.
April38.3 °F60.5 °F3.77 in.
May50.2 °F72.0 °F4.88 in.
June60.1 °F81.1 °F5.12 in.
July63.4 °F84.3 °F4.09 in.
August61.3 °F82.5 °F4.22 in.
September52.9 °F76.3 °F3.55 in.
October41.3 °F63.5 °F3.01 in.
November29.8 °F48.1 °F2.17 in.
December19.5 °F35.2 °F2.03 in.
Annual39.5 °F59.5 °F38.94 in.

Climate Data for Lyndon Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost100-125 Days
Plant Hardiness ZoneZone 5b : -15°F to -10°F
Plant Hardiness Zone - 2012Zone 5b : -15°F to -10°F
Current Drought ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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