Frost dates in Humboldt, SD
The average last spring frost in Humboldt is around May 18 and the first fall frost is around September 27. That gives Humboldt an average growing season of about 132 days.
Last spring frost
| Early (10% chance after) | May 7 |
|---|---|
| Average (50%) | May 18 |
| Late (90%) | May 23 |
First fall frost
| Early (10%) | September 21 |
|---|---|
| Average (50%) | September 27 |
| Late (90% chance before) | October 5 |