Frost dates in Watertown, SD
The average last spring frost in Watertown is around May 14 and the first fall frost is around September 25. That gives Watertown an average growing season of about 134 days.
Last spring frost
| Early (10% chance after) | April 26 |
|---|---|
| Average (50%) | May 14 |
| Late (90%) | May 30 |
First fall frost
| Early (10%) | September 12 |
|---|---|
| Average (50%) | September 25 |
| Late (90% chance before) | October 11 |