Frost dates in Mattoon, IL
The average last spring frost in Mattoon is around April 16 and the first fall frost is around October 19. That gives Mattoon an average growing season of about 186 days.
Last spring frost
| Early (10% chance after) | March 31 |
|---|---|
| Average (50%) | April 16 |
| Late (90%) | May 2 |
First fall frost
| Early (10%) | October 6 |
|---|---|
| Average (50%) | October 19 |
| Late (90% chance before) | November 3 |