South Shore, SD 57263 Frost Dates
57263, near South Shore, SD: the frost window
The last spring frost here typically falls around 05/07, about 252 days from today. Fall's first freeze usually shows up around 09/28, roughly 143 days after the last spring frost.
Zone 4b (-25 to -20°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for South Shore, not a forecast for this year.
Stretching the season past the first frost
South Shore's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/07 isn't a guarantee
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/24 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/20 and only about 1 year in 10 sees frost after that.
South Shore against the rest of the dataset
About 143 days separate South Shore's last and first frost, putting it 36,652 of 40,283 ZIP codes nationally. Within SD, it ranks 272 of 378.
Learn more
Two guides worth reading on 57263: local microclimates, on what one yard in South Shore can differ from the 57263 normal, and zone vs. frost date, on why Zone 4b and South Shore's frost date answer different questions.