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 = 'grand-river' and st_surl='iowa' and iso_cc = 'US' and prim_loc in (1,2) Grand River Iowa Climate Data - Updated February 2026

Grand River Iowa Climate Data

Monthly Average Climate Data for Grand River Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January13.1 °F32.1 °F0.93 in.
February16.9 °F36.8 °F1.36 in.
March27.8 °F49.7 °F2.19 in.
April38.3 °F61.8 °F4.05 in.
May49.9 °F71.6 °F5.43 in.
June60.0 °F81.1 °F5.16 in.
July64.4 °F85.5 °F4.41 in.
August61.8 °F83.9 °F4.28 in.
September52.6 °F76.7 °F3.91 in.
October40.6 °F64.4 °F2.85 in.
November28.6 °F49.5 °F2.09 in.
December18.7 °F37.0 °F1.44 in.
Annual39.4 °F60.8 °F38.1 in.

Climate Data for Grand River Iowa

Average First Frost DateOct. 11 - Oct. 20
Average Last Frost DateApr. 11 - Apr. 20
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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