Frost dates in Harrison, ID
The average last spring frost in Harrison is around May 13 and the first fall frost is around October 4. That gives Harrison an average growing season of about 144 days.
Last spring frost
| Early (10% chance after) | April 18 |
|---|---|
| Average (50%) | May 13 |
| Late (90%) | June 10 |
First fall frost
| Early (10%) | September 16 |
|---|---|
| Average (50%) | October 4 |
| Late (90% chance before) | October 28 |