California frost dates: H
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Hacienda Heights | rare frost | 10b | ||
| Half Moon Bay | Feb 6 | Dec 17 | 314 d | 10a |
| Hamilton City | Feb 25 | Dec 2 | 280 d | 9b |
| Hanford | Feb 7 | Dec 1 | 297 d | 9a |
| Happy Camp | May 1 | Oct 12 | 164 d | 8b |
| Harbor City | Jan 9 | Jan 5 | 361 d | 10b |
| Harmony | Jan 19 | Jan 14 | 360 d | 10a |
| Hat Creek | May 29 | Sep 19 | 113 d | 7a |
| Hathaway Pines | May 7 | Oct 28 | 174 d | 8b |
| Hawaiian Gardens | rare frost | 10a | ||
| Hawthorne | rare frost | 10b | ||
| Hayfork | Apr 16 | Oct 31 | 198 d | 8b |
| Hayward | Jan 2 | Dec 25 | 357 d | 10a |
| Healdsburg | Feb 15 | Dec 2 | 290 d | 9b |
| Heber | Jan 3 | Dec 27 | 358 d | 10a |
| Helendale | Mar 18 | Nov 11 | 238 d | 8b |
| Helm | Feb 27 | Nov 26 | 272 d | 9a |
| Hemet | Jan 31 | Dec 10 | 313 d | 9b |
| Herald | Feb 9 | Dec 5 | 299 d | 9b |
| Hercules | Jan 17 | Dec 27 | 344 d | 9b |
| Herlong | May 21 | Oct 1 | 133 d | 7a |
| Hermosa Beach | rare frost | 11a | ||
| Hesperia | Feb 28 | Dec 1 | 276 d | 8b |
| Hickman | Jan 6 | Dec 20 | 348 d | 9b |
| Hidden Valley Lake | Apr 10 | Nov 6 | 210 d | 9a |
| Highland | Jan 27 | Dec 19 | 326 d | 10a |
| Hilmar | Jan 6 | Dec 20 | 348 d | 9a |
| Hinkley | Feb 22 | Nov 23 | 274 d | 9a |
| Hollister | Feb 19 | Dec 1 | 285 d | 9b |
| Holt | Feb 5 | Dec 8 | 306 d | 9b |
| Holtville | Jan 3 | Dec 27 | 358 d | 10a |
| Holy City | Feb 2 | Dec 6 | 307 d | 10a |
| Homeland | Jan 31 | Dec 10 | 313 d | 9b |
| Homewood | Jun 4 | Oct 3 | 121 d | 7a |
| Honeydew | rare frost | 9b | ||
| Hood | Feb 2 | Dec 2 | 303 d | 9b |
| Hoopa | Mar 12 | Nov 26 | 259 d | 9a |
| Hopland | Feb 25 | Dec 3 | 281 d | 9b |
| Hornbrook | May 12 | Oct 8 | 149 d | 8a |
| Hornitos | Mar 3 | Nov 24 | 266 d | 9b |
| Hughson | Jan 31 | Dec 5 | 308 d | 9b |
| Hume | Jun 1 | Oct 7 | 128 d | 7b |
| Huntington Beach | rare frost | 10b | ||
| Huntington Park | rare frost | 10b | ||
| Huron | Feb 27 | Nov 26 | 272 d | 9b |
| Hyampom | Apr 16 | Oct 31 | 198 d | 8b |
| Hydesville | Feb 1 | Dec 19 | 321 d | 9b |