Frost dates in Idaho Falls, ID
The average last spring frost in Idaho Falls is around May 20 and the first fall frost is around September 22. That gives Idaho Falls an average growing season of about 125 days.
Last spring frost
| Early (10% chance after) | April 30 |
|---|---|
| Average (50%) | May 20 |
| Late (90%) | June 13 |
First fall frost
| Early (10%) | September 8 |
|---|---|
| Average (50%) | September 22 |
| Late (90% chance before) | October 14 |