Iowa frost dates: A
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Ackley | Apr 28 | Oct 10 | 165 d | 5a |
| Ackworth | Apr 21 | Oct 15 | 177 d | 5b |
| Adair | May 2 | Oct 3 | 154 d | 5b |
| Adel | Apr 25 | Oct 10 | 168 d | 5b |
| Afton | Apr 28 | Oct 11 | 166 d | 5b |
| Agency | Apr 23 | Oct 14 | 174 d | 5b |
| Ainsworth | Apr 28 | Oct 11 | 166 d | 5b |
| Akron | May 1 | Oct 4 | 156 d | 5a |
| Albert City | Apr 30 | Oct 5 | 158 d | 5a |
| Albia | Apr 24 | Oct 16 | 175 d | 5b |
| Albion | Apr 30 | Oct 6 | 159 d | 5a |
| Alburnett | Apr 28 | Oct 12 | 167 d | 5a |
| Alden | Apr 28 | Oct 10 | 165 d | 5a |
| Alexander | Apr 29 | Oct 9 | 163 d | 5a |
| Algona | Apr 30 | Oct 6 | 159 d | 5a |
| Alleman | Apr 23 | Oct 15 | 175 d | 5b |
| Allerton | Apr 21 | Oct 19 | 181 d | 5b |
| Allison | Apr 27 | Oct 8 | 164 d | 5a |
| Alta | Apr 25 | Oct 13 | 171 d | 5a |
| Alta Vista | May 2 | Oct 5 | 156 d | 5a |
| Alton | Apr 30 | Oct 3 | 156 d | 5a |
| Altoona | Apr 23 | Oct 15 | 175 d | 5b |
| Alvord | May 1 | Oct 4 | 156 d | 5a |
| Amana | Apr 27 | Oct 11 | 167 d | 5b |
| Ames | Apr 26 | Oct 8 | 165 d | 5b |
| Anamosa | May 1 | Oct 4 | 156 d | 5a |
| Andover | Apr 13 | Oct 26 | 196 d | 5a |
| Andrew | Apr 25 | Oct 14 | 172 d | 5a |
| Anita | Apr 30 | Oct 2 | 155 d | 5b |
| Ankeny | Apr 23 | Oct 15 | 175 d | 5b |
| Anthon | May 1 | Oct 1 | 153 d | 5a |
| Aplington | Apr 27 | Oct 8 | 164 d | 5a |
| Arcadia | Apr 27 | Oct 10 | 166 d | 5a |
| Archer | May 1 | Oct 7 | 159 d | 5a |
| Aredale | Apr 29 | Oct 9 | 163 d | 5a |
| Argyle | Apr 17 | Oct 22 | 188 d | 6a |
| Arion | Apr 27 | Oct 11 | 167 d | 5b |
| Arispe | Apr 28 | Oct 11 | 166 d | 5b |
| Arlington | May 8 | Oct 1 | 146 d | 4b |
| Armstrong | May 4 | Oct 1 | 150 d | 5a |
| Arnolds Park | May 1 | Oct 6 | 158 d | 5a |
| Arthur | Apr 27 | Oct 12 | 168 d | 5a |
| Ashton | May 5 | Oct 3 | 151 d | 5a |
| Aspinwall | Apr 27 | Oct 11 | 167 d | 5a |
| Atalissa | Apr 18 | Oct 22 | 187 d | 5b |
| Atkins | Apr 27 | Oct 11 | 167 d | 5a |
| Atlantic | Apr 30 | Oct 2 | 155 d | 5a |
| Auburn | Apr 30 | Oct 6 | 159 d | 5a |
| Audubon | May 2 | Oct 3 | 154 d | 5a |
| Aurelia | May 4 | Oct 4 | 153 d | 5a |
| Aurora | May 4 | Oct 1 | 150 d | 5a |
| Austinville | Apr 27 | Oct 8 | 164 d | 5a |
| Avoca | Apr 27 | Oct 9 | 165 d | 5b |
| Ayrshire | Apr 27 | Oct 7 | 163 d | 5a |