Frost dates in Dennison, MN
The average last spring frost in Dennison is around May 10 and the first fall frost is around September 30. That gives Dennison an average growing season of about 143 days.
Last spring frost
| Early (10% chance after) | April 24 |
|---|---|
| Average (50%) | May 10 |
| Late (90%) | May 22 |
First fall frost
| Early (10%) | September 17 |
|---|---|
| Average (50%) | September 30 |
| Late (90% chance before) | October 14 |