Frost dates in Rock Island, WA
The average last spring frost in Rock Island is around April 12 and the first fall frost is around October 23. That gives Rock Island an average growing season of about 194 days.
Last spring frost
| Early (10% chance after) | March 26 |
|---|---|
| Average (50%) | April 12 |
| Late (90%) | April 26 |
First fall frost
| Early (10%) | October 10 |
|---|---|
| Average (50%) | October 23 |
| Late (90% chance before) | November 4 |