Timber Lake, SD 57661 Frost Dates
Timber Lake, SD: when does the frost end?
Around 05/10 is the usual last spring frost, about 255 days away. Fall's first freeze usually shows up around 09/30, roughly 141 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Timber Lake in Zone 4b (-25 to -20°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 5 weeks until Timber Lake'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
05/10 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/29 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/23 and only about 1 year in 10 sees frost after that.
Timber Lake against the rest of the dataset
Timber Lake's growing season runs about 141 days, ranking 36,964 of 40,283 US ZIP codes measured here, longest to shortest. Within SD, it ranks 297 of 378.
Learn more
Before leaning on 57661's figures: the frost range explains how to read the range around Timber Lake's dates instead of trusting one, while local microclimates explains what one yard in Timber Lake can differ from the 57661 normal.