Warner, SD 57479 Frost Dates
When can you plant in Warner, SD?
Around 05/08 is the usual last spring frost, about 253 days away. The first fall frost typically arrives around 09/29, about 144 frost-free days later.
Zone 4a (-30 to -25°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 Warner, not a forecast for this year.
What to do before the first frost
About 5 weeks of growing season left in Warner before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/08 isn't a guarantee
05/08 is the middle of 30 years of NOAA records, not a promise. Plant by 04/25 and you're betting against frost in roughly 9 years out of 10. 05/21 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Warner compares
At roughly 144 frost-free days, Warner places 36,442 of 40,283 ZIP codes in this dataset. Within SD, it ranks 260 of 378.
Learn more
local microclimates covers what one yard in Warner can differ from the 57479 normal. zone vs. frost date covers why Zone 4a and Warner's frost date answer different questions.