Oregon frost dates: S
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Saint Benedict | Apr 27 | Nov 4 | 191 d | 8b |
| Saint Helens | Apr 18 | Nov 7 | 203 d | 8b |
| Saint Paul | Mar 21 | Nov 22 | 246 d | 8b |
| Salem | Apr 3 | Nov 1 | 212 d | 8b |
| Sandy | Mar 27 | Nov 18 | 236 d | 8b |
| Scappoose | Apr 10 | Nov 2 | 206 d | 8b |
| Scio | Mar 29 | Nov 6 | 222 d | 8b |
| Scotts Mills | Apr 27 | Nov 4 | 191 d | 8b |
| Scottsburg | Apr 11 | Nov 6 | 209 d | 9a |
| Seal Rock | Feb 19 | Dec 16 | 300 d | 9a |
| Seaside | Apr 2 | Nov 12 | 224 d | 8b |
| Selma | May 1 | Oct 12 | 164 d | 8b |
| Seneca | frost any month | 5b | ||
| Shady Cove | Apr 29 | Oct 17 | 171 d | 8a |
| Shaniko | May 22 | Oct 3 | 134 d | 6b |
| Shedd | Apr 11 | Oct 30 | 202 d | 8b |
| Sheridan | Apr 16 | Nov 1 | 199 d | 8b |
| Sherwood | Mar 21 | Nov 22 | 246 d | 8b |
| Siletz | Mar 12 | Dec 10 | 273 d | 9a |
| Silver Lake | frost any month | 6a | ||
| Silverton | Mar 28 | Nov 10 | 227 d | 8b |
| Sisters | frost any month | 7a | ||
| Sixes | Feb 17 | Dec 3 | 289 d | 9b |
| South Beach | Feb 19 | Dec 16 | 300 d | 9b |
| Sprague River | May 31 | Sep 21 | 113 d | 6a |
| Spray | May 9 | Sep 27 | 141 d | 7a |
| Springfield | Apr 11 | Oct 23 | 195 d | 8b |
| Stanfield | Apr 26 | Oct 10 | 167 d | 7a |
| Stayton | Mar 29 | Nov 6 | 222 d | 8b |
| Sublimity | Mar 29 | Nov 6 | 222 d | 8b |
| Summer Lake | Jun 8 | Sep 15 | 99 d | 6b |
| Summerville | May 24 | Sep 18 | 117 d | 6b |
| Sumpter | frost any month | 6b | ||
| Sutherlin | Mar 31 | Nov 5 | 219 d | 8b |
| Sweet Home | Apr 12 | Oct 28 | 199 d | 8b |
| Swisshome | Feb 15 | Dec 9 | 297 d | 9a |