Frost dates in Happy Valley, OR
The average last spring frost in Happy Valley is around April 2 and the first fall frost is around November 9. That gives Happy Valley an average growing season of about 221 days.
Last spring frost
| Early (10% chance after) | February 19 |
|---|---|
| Average (50%) | April 2 |
| Late (90%) | April 22 |
First fall frost
| Early (10%) | October 21 |
|---|---|
| Average (50%) | November 9 |
| Late (90% chance before) | December 8 |