Frost dates in Grafton, ND
The average last spring frost in Grafton is around May 16 and the first fall frost is around September 22. That gives Grafton an average growing season of about 129 days.
Last spring frost
| Early (10% chance after) | April 26 |
|---|---|
| Average (50%) | May 16 |
| Late (90%) | June 6 |
First fall frost
| Early (10%) | September 3 |
|---|---|
| Average (50%) | September 22 |
| Late (90% chance before) | October 7 |