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 = 'charter-oak' and st_surl='iowa' and iso_cc = 'US' and prim_loc in (1,2) Charter Oak Iowa Climate Data - Updated February 2026

Charter Oak Iowa Climate Data

Monthly Average Climate Data for Charter Oak Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January10.2 °F28.9 °F0.7 in.
February14.4 °F33.8 °F0.91 in.
March25.5 °F47.2 °F1.73 in.
April36.3 °F60.6 °F3.39 in.
May48.6 °F71.4 °F4.56 in.
June59.5 °F81.3 °F4.84 in.
July63.2 °F84.4 °F3.89 in.
August60.4 °F82.3 °F4.3 in.
September51.4 °F76.4 °F3.16 in.
October38.9 °F63.5 °F2.32 in.
November25.9 °F47.2 °F1.39 in.
December15.8 °F33.8 °F1.16 in.
Annual37.5 °F59.2 °F32.35 in.

Climate Data for Charter Oak Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateApr. 21 - Apr. 30
Average Days With Frost100-125 Days
Plant Hardiness ZoneZone 5a : -20°F to -15°F
Plant Hardiness Zone - 2012Zone 5a : -20°F to -15°F
Current Drought ConditionsNormal
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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