Frost Dates for Sun Prairie, MT
Frost Dates
Sun Prairie, MT
See the average dates of the last frost of spring and the first frost of fall for your location across the U.S. and Canada.
| Nearest Climate Station | Altitude | Last Spring Frost | First Fall Frost | Growing Season |
|---|---|---|---|---|
| GREAT FALLS INTL AP, MT | 3664' | May 25 | Sep 19 | 116 days |
Last and first frost dates are 30% probability. Calculated using 1991-2020 Climate Normals from NOAA.
Our frost dates are based on 1991–2020 climate data from the National Oceanic and Atmospheric Administration (NOAA). We use a 30% probability threshold, meaning there’s about a 3 in 10 chance frost will occur before or after the given date. Because microclimates vary—your backyard might be warmer or cooler than nearby towns—use these dates as a flexible guide, not a guarantee.