Frost dates in Hamilton, MT
The average last spring frost in Hamilton is around May 24 and the first fall frost is around September 21. That gives Hamilton an average growing season of about 120 days.
Last spring frost
| Early (10% chance after) | May 4 |
|---|---|
| Average (50%) | May 24 |
| Late (90%) | June 8 |
First fall frost
| Early (10%) | September 8 |
|---|---|
| Average (50%) | September 21 |
| Late (90% chance before) | October 8 |