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

Merrill Iowa Climate Data

Monthly Average Climate Data for Merrill Iowa

Switch Data to Celsius/Metric Units
MonthAvg. LowAvg. HighAvg. Precip
January9.1 °F27.9 °F0.61 in.
February13.1 °F32.9 °F0.75 in.
March24.5 °F45.8 °F1.55 in.
April35.2 °F59.9 °F3.17 in.
May47.9 °F71.3 °F3.96 in.
June59.3 °F81.8 °F4.41 in.
July62.5 °F84.4 °F3.21 in.
August60.0 °F82.4 °F3.49 in.
September50.3 °F76.0 °F3.17 in.
October37.6 °F63.1 °F2.47 in.
November24.7 °F46.4 °F1.25 in.
December14.4 °F32.8 °F0.89 in.
Annual36.6 °F58.7 °F28.93 in.

Climate Data for Merrill Iowa

Average First Frost DateOct. 1 - Oct. 10
Average Last Frost DateApr. 21 - Apr. 30
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 ConditionsAbnormally Dry
Köppen Climate ClassificationDfa - Humid Continental Hot Summers With Year Around Precipitation
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