Oacoma, SD 57365 Frost Dates
57365, near Oacoma, SD: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/07, roughly 158 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 Oacoma, not a forecast for this year.
Stretching the season past the first frost
Oacoma'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.
The actual range around Oacoma's last frost
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/14 and only about 1 year in 10 sees frost after that.
Oacoma against the rest of the dataset
Oacoma's growing season runs about 158 days, ranking 33,119 of 40,283 US ZIP codes measured here, longest to shortest. Within SD, it ranks 54 of 378.
Learn more
Two guides worth reading on 57365: local microclimates, on what one yard in Oacoma can differ from the 57365 normal, and zone vs. frost date, on why Zone 5a and Oacoma's frost date answer different questions.