Frost dates in Petersburg, ND
The average last spring frost in Petersburg is around May 18 and the first fall frost is around September 22. That gives Petersburg an average growing season of about 127 days.
Last spring frost
| Early (10% chance after) | May 3 |
|---|---|
| Average (50%) | May 18 |
| Late (90%) | May 30 |
First fall frost
| Early (10%) | September 10 |
|---|---|
| Average (50%) | September 22 |
| Late (90% chance before) | October 6 |