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 = 'san-jose' and st_surl='illinois' and iso_cc = 'US' and prim_loc in (1,2) San Jose Illinois Climate Data - Updated February 2026

San Jose Illinois Climate Data

Monthly Average Climate Data for San Jose Illinois

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January17.4 °F34.1 °F2.11 in.
February20.8 °F39.0 °F1.85 in.
March30.4 °F51.1 °F2.53 in.
April41.2 °F64.2 °F3.89 in.
May52.7 °F74.5 °F4.59 in.
June62.1 °F83.2 °F4.51 in.
July65.1 °F86.1 °F4.18 in.
August62.8 °F84.6 °F3.51 in.
September54.6 °F79.6 °F3.32 in.
October43.0 °F66.9 °F3.09 in.
November32.1 °F51.7 °F2.8 in.
December23.1 °F39.4 °F2.2 in.
Annual42.1 °F62.9 °F38.58 in.

Climate Data for San Jose Illinois

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
Average Days With Frost75-100 Days
Plant Hardiness ZoneZone 6a : -10°F to -5°F
Plant Hardiness Zone - 2012Zone 5b : -15°F to -10°F
Current Drought ConditionsModerate Drought
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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