Frost dates in Havre, MT
The average last spring frost in Havre is around May 14 and the first fall frost is around September 21. That gives Havre an average growing season of about 130 days.
Last spring frost
| Early (10% chance after) | April 29 |
|---|---|
| Average (50%) | May 14 |
| Late (90%) | June 1 |
First fall frost
| Early (10%) | September 11 |
|---|---|
| Average (50%) | September 21 |
| Late (90% chance before) | October 5 |