New Witten, SD 57541 Frost Dates
New Witten, SD: when does the frost end?
Typically, the last spring freeze lands around 05/01, roughly 246 days out. Fall's first freeze usually shows up around 10/10, roughly 162 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts New Witten in Zone 5a (-20 to -15°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 6 weeks until New Witten's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/16 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/15 and only about 1 year in 10 sees frost after that.
New Witten against the rest of the dataset
About 162 days separate New Witten's last and first frost, putting it 31,902 of 40,283 ZIP codes nationally. Within SD, it ranks 28 of 378.
Learn more
Before leaning on 57541's figures: zone vs. frost date explains why Zone 5a and New Witten's frost date answer different questions, while the frost range explains how to read the range around New Witten's dates instead of trusting one.