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 = 'harper' and st_surl='iowa' and iso_cc = 'US' and prim_loc in (1,2) Harper Iowa Climate Data - Updated February 2026

Harper Iowa Climate Data

Monthly Average Climate Data for Harper Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January12.9 °F30.0 °F1.23 in.
February16.6 °F34.7 °F1.5 in.
March27.4 °F47.8 °F2.26 in.
April38.6 °F61.1 °F3.78 in.
May50.6 °F71.5 °F5.05 in.
June61.0 °F81.1 °F5.29 in.
July64.3 °F84.7 °F4.14 in.
August61.7 °F82.9 °F4.42 in.
September52.8 °F76.5 °F3.54 in.
October40.9 °F63.7 °F2.85 in.
November29.2 °F48.3 °F2.17 in.
December18.9 °F35.4 °F1.62 in.
Annual39.6 °F59.8 °F37.85 in.

Climate Data for Harper Iowa

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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