Gregory, SD 57533 Frost Dates
Gregory, SD: when does the frost end?
The last spring frost here typically falls around 05/01, about 246 days from today. Fall's first freeze usually shows up around 10/10, roughly 162 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 Gregory, not a forecast for this year.
Stretching the season past the first frost
With roughly 6 weeks until Gregory's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/16 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/15 and only about 1 year in 10 sees frost after that.
Gregory against the rest of the dataset
Gregory's growing season runs about 162 days, ranking 31,786 of 40,283 US ZIP codes measured here, longest to shortest. Within SD, it ranks 25 of 378.
Learn more
Before leaning on 57533's figures: local microclimates explains what one yard in Gregory can differ from the 57533 normal, while zone vs. frost date explains why Zone 5a and Gregory's frost date answer different questions.