Frost dates in St. Charles, IA
The average last spring frost in St. Charles is around April 27 and the first fall frost is around October 9. That gives St. Charles an average growing season of about 165 days.
Last spring frost
| Early (10% chance after) | April 15 |
|---|---|
| Average (50%) | April 27 |
| Late (90%) | May 10 |
First fall frost
| Early (10%) | September 24 |
|---|---|
| Average (50%) | October 9 |
| Late (90% chance before) | October 25 |