North Dakota frost dates: H
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Hague | May 8 | Sep 30 | 145 d | 4a |
| Halliday | May 20 | Sep 21 | 124 d | 4a |
| Hamilton | May 12 | Sep 30 | 141 d | 4a |
| Hampden | May 15 | Sep 22 | 130 d | 4a |
| Hankinson | May 4 | Oct 3 | 152 d | 4b |
| Hannaford | May 17 | Sep 23 | 129 d | 4a |
| Hannah | May 17 | Sep 26 | 132 d | 3b |
| Hansboro | May 20 | Sep 26 | 129 d | 3b |
| Harvey | May 13 | Sep 28 | 138 d | 4a |
| Harwood | May 10 | Sep 30 | 143 d | 4a |
| Hatton | May 13 | Sep 27 | 137 d | 4a |
| Havana | May 7 | Oct 1 | 147 d | 4a |
| Hazelton | May 12 | Sep 27 | 138 d | 4a |
| Hazen | May 21 | Sep 20 | 122 d | 4a |
| Hebron | May 19 | Sep 21 | 125 d | 4a |
| Hensel | May 12 | Sep 30 | 141 d | 4a |
| Hettinger | May 24 | Sep 18 | 117 d | 4b |
| Hillsboro | May 2 | Oct 9 | 160 d | 4a |
| Hoople | May 4 | Oct 7 | 156 d | 4a |
| Hope | May 10 | Sep 24 | 137 d | 4a |
| Horace | May 4 | Oct 2 | 151 d | 4a |
| Hunter | May 2 | Oct 9 | 160 d | 4a |
| Hurdsfield | May 13 | Sep 29 | 139 d | 4a |