Frost dates in Sully County, South Dakota

Jagged badland formations above a grassy plain in Badlands National Park, South Dakota — Photo: DimiTalen, CC0, via Wikimedia Commons

The average last spring frost in Sully County falls May 8 and the average first fall frost Oct 2, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 4b. Places: Agar, Onida. Pick a ZIP for 10% and 90% odds, soil temperature and the 7-day freeze forecast.

ZIP	Place	Last spring frost	First fall frost	Zone
57520	Agar	May 8	Oct 2	4b
57564	Onida	May 8	Oct 2	4b

Nearby counties

Hughes County Potter County Hyde County Stanley County Walworth County Faulk County

All South Dakota counties · Download South Dakota frost dates (CSV)

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