Frost dates in Mount Vernon, WA
The average last spring frost in Mount Vernon is around April 12 and the first fall frost is around October 17. That gives Mount Vernon an average growing season of about 188 days.
Last spring frost
| Early (10% chance after) | March 24 |
|---|---|
| Average (50%) | April 12 |
| Late (90%) | April 27 |
First fall frost
| Early (10%) | September 27 |
|---|---|
| Average (50%) | October 17 |
| Late (90% chance before) | November 7 |