Frost dates in Humboldt, IA
The average last spring frost in Humboldt is around April 17 and the first fall frost is around October 7. That gives Humboldt an average growing season of about 173 days.
Last spring frost
| Early (10% chance after) | April 9 |
|---|---|
| Average (50%) | April 17 |
| Late (90%) | May 4 |
First fall frost
| Early (10%) | October 2 |
|---|---|
| Average (50%) | October 7 |
| Late (90% chance before) | October 27 |