Woonsocket, SD 57385 Frost Dates
57385, near Woonsocket, SD: the frost window
Typically, the last spring freeze lands around 04/27, roughly 242 days out. Fall's first freeze usually shows up around 10/11, roughly 167 days after the last spring frost.
Zone 5a (-20 to -15°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 Woonsocket, not a forecast for this year.
Stretching the season past the first frost
Woonsocket's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/10 and only about 1 year in 10 sees frost after that.
Woonsocket against the rest of the dataset
About 167 days separate Woonsocket's last and first frost, putting it 30,128 of 40,283 ZIP codes nationally. Within SD, it ranks 3 of 378.
Learn more
Two guides worth reading on 57385: zone vs. frost date, on why Zone 5a and Woonsocket's frost date answer different questions, and the frost range, on how to read the range around Woonsocket's dates instead of trusting one.