Frost dates in Hysham, MT
The average last spring frost in Hysham is around May 13 and the first fall frost is around September 23. That gives Hysham an average growing season of about 133 days.
Last spring frost
| Early (10% chance after) | April 25 |
|---|---|
| Average (50%) | May 13 |
| Late (90%) | May 29 |
First fall frost
| Early (10%) | September 10 |
|---|---|
| Average (50%) | September 23 |
| Late (90% chance before) | October 12 |