South Dakota frost dates: A
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Aberdeen | May 9 | Sep 26 | 140 d | 4a |
| Agar | May 8 | Oct 2 | 147 d | 4b |
| Akaska | May 8 | Oct 1 | 146 d | 4b |
| Alcester | May 1 | Oct 4 | 156 d | 5a |
| Alexandria | May 8 | Sep 29 | 144 d | 5a |
| Allen | May 13 | Oct 2 | 142 d | 5a |
| Alpena | May 2 | Oct 8 | 159 d | 4b |
| Amherst | May 13 | Sep 26 | 136 d | 4a |
| Andover | May 6 | Oct 4 | 151 d | 4b |
| Arlington | May 3 | Oct 2 | 152 d | 4b |
| Armour | May 3 | Oct 6 | 156 d | 5a |
| Artesian | May 9 | Sep 28 | 142 d | 4b |
| Ashton | May 11 | Sep 27 | 139 d | 4b |
| Astoria | May 6 | Oct 3 | 150 d | 4b |
| Aurora | May 6 | Oct 1 | 148 d | 4b |
| Avon | May 1 | Oct 7 | 159 d | 5a |