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 = 'rock-falls' and st_surl='illinois' and iso_cc = 'US' and prim_loc in (1,2) Rock Falls Illinois Climate Data - Updated February 2026

Rock Falls Illinois Climate Data

Monthly Average Climate Data for Rock Falls Illinois

Switch Data to Celsius/Metric Units

Month	Avg. Low	Avg. High	Avg. Precip
January	13.1 °F	29.5 °F	1.71 in.
February	16.9 °F	34.0 °F	1.72 in.
March	27.4 °F	46.6 °F	2.39 in.
April	38.0 °F	60.2 °F	3.83 in.
May	50.0 °F	71.6 °F	4.92 in.
June	59.8 °F	80.7 °F	5.42 in.
July	63.0 °F	83.6 °F	4.28 in.
August	60.9 °F	81.9 °F	4.28 in.
September	52.5 °F	76.0 °F	3.76 in.
October	40.8 °F	63.1 °F	2.81 in.
November	29.7 °F	47.7 °F	2.29 in.
December	19.7 °F	35.1 °F	1.94 in.
Annual	39.3 °F	59.2 °F	39.35 in.

Climate Data for Rock Falls Illinois

Average First Frost Date	Oct. 1 - Oct. 10
Average Last Frost Date	Apr. 21 - Apr. 30
Average Days With Frost	100-125 Days
Plant Hardiness Zone	Zone 5b : -15°F to -10°F
Plant Hardiness Zone - 2012	Zone 5b : -15°F to -10°F
Current Drought Conditions	Abnormally Dry
Köppen Climate Classification	Dfa - Humid Continental Hot Summers With Year Around Precipitation

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