Frost dates in Riggins, ID
The average last spring frost in Riggins is around April 22 and the first fall frost is around October 21. That gives Riggins an average growing season of about 182 days.
Last spring frost
| Early (10% chance after) | March 30 |
|---|---|
| Average (50%) | April 22 |
| Late (90%) | May 22 |
First fall frost
| Early (10%) | October 1 |
|---|---|
| Average (50%) | October 21 |
| Late (90% chance before) | November 9 |