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 = 'mount-vernon' and st_surl='south-dakota' and iso_cc = 'US' and prim_loc in (1,2) Mount Vernon South Dakota Climate Data - Updated February 2026

Mount Vernon South Dakota Climate Data

Monthly Average Climate Data for Mount Vernon South Dakota

Switch Data to Celsius/Metric Units

Month	Avg. Low	Avg. High	Avg. Precip
January	8.1 °F	27.4 °F	0.52 in.
February	12.0 °F	32.7 °F	0.74 in.
March	22.5 °F	44.4 °F	1.15 in.
April	34.3 °F	58.1 °F	2.89 in.
May	46.8 °F	69.9 °F	3.54 in.
June	57.9 °F	80.2 °F	3.81 in.
July	62.3 °F	85.9 °F	2.99 in.
August	60.0 °F	83.8 °F	2.87 in.
September	50.9 °F	76.2 °F	2.62 in.
October	36.9 °F	61.2 °F	2.08 in.
November	23.5 °F	45.0 °F	0.89 in.
December	12.8 °F	31.4 °F	0.68 in.
Annual	35.7 °F	58 °F	24.78 in.

Climate Data for Mount Vernon South Dakota

Average First Frost Date	Oct. 1 - Oct. 10
Average Last Frost Date	May 1 - May 10
Average Days With Frost	125-150 Days
Plant Hardiness Zone	Zone 5a : -20°F to -15°F
Plant Hardiness Zone - 2012	Zone 4b : -25°F to -20°F
Current Drought Conditions	Abnormally Dry
Köppen Climate Classification	Dfa - Humid Continental Hot Summers With Year Around Precipitation

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