Frost dates in Rock Island, IL
The average last spring frost in Rock Island is around April 24 and the first fall frost is around October 13. That gives Rock Island an average growing season of about 172 days.
Last spring frost
| Early (10% chance after) | April 13 |
|---|---|
| Average (50%) | April 24 |
| Late (90%) | May 9 |
First fall frost
| Early (10%) | September 29 |
|---|---|
| Average (50%) | October 13 |
| Late (90% chance before) | October 29 |