North Dakota frost dates: A
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Abercrombie | May 4 | Oct 3 | 152 d | 4a |
| Absaraka | May 9 | Oct 1 | 145 d | 4a |
| Adams | May 15 | Sep 22 | 130 d | 3b |
| Agate | May 22 | Sep 20 | 121 d | 3b |
| Alamo | May 18 | Sep 20 | 125 d | 3b |
| Alexander | May 9 | Sep 27 | 141 d | 4a |
| Almont | May 17 | Sep 21 | 127 d | 4a |
| Alsen | May 17 | Sep 26 | 132 d | 3b |
| Ambrose | May 17 | Sep 23 | 129 d | 4a |
| Amenia | May 9 | Oct 1 | 145 d | 4a |
| Amidon | May 12 | Sep 29 | 140 d | 4b |
| Anamoose | May 12 | Sep 27 | 138 d | 4a |
| Aneta | May 11 | Sep 28 | 140 d | 4a |
| Antler | May 14 | Sep 25 | 134 d | 3b |
| Argusville | May 9 | Oct 1 | 145 d | 4a |
| Arnegard | May 9 | Sep 27 | 141 d | 4a |
| Arthur | May 9 | Oct 1 | 145 d | 4a |
| Arvilla | May 11 | Sep 28 | 140 d | 4a |
| Ashley | May 13 | Sep 28 | 138 d | 4b |
| Ayr | May 9 | Oct 1 | 145 d | 4a |