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

Plymouth Iowa Climate Data

Monthly Average Climate Data for Plymouth Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January7.2 °F23.9 °F0.96 in.
February11.2 °F28.5 °F1.1 in.
March23.4 °F41.0 °F1.98 in.
April35.1 °F56.5 °F3.92 in.
May47.4 °F68.6 °F5.22 in.
June58.0 °F78.7 °F5.5 in.
July61.6 °F81.8 °F4.62 in.
August58.9 °F79.5 °F3.96 in.
September50.2 °F73.4 °F3.41 in.
October37.7 °F59.9 °F2.61 in.
November25.4 °F43.4 °F1.74 in.
December14.2 °F29.7 °F1.33 in.
Annual35.9 °F55.4 °F36.35 in.

Climate Data for Plymouth Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateMay 1 - May 10
Average Days With Frost125-150 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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