Frost dates for 59866Saint Regis, MT
Frost is possible in any month near Saint Regis, based on NOAA 1991-2020 records for the Haugan 1 W, MT station.
Frost is possible in any month. Even summer nights can drop to freezing at this station, so protect tender plants whenever cold nights are forecast.
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | — | — | 44 days | 100% |
| Frost / freeze (32°F) | — | — | 90 days | 100% |
| Hard freeze (28°F) | Apr 30 · May 12 · May 30 | Sep 6 · Sep 24 · Oct 13 | 133 days | 100% |
Where these dates come from
ZIP code 59866 is matched to the NOAA station Haugan 1 W, MT, 19.9 km away, at 3,160 ft elevation (35 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Haugan 1 W, MT (used) | 3,160 ft | — | — |
| Saint Regis 1 Ne, MT | 2,660 ft | — | — |
| Superior, MT | 2,710 ft | May 17 | Sep 23 |
| Thompson Falls Ph, MT | 2,380 ft | May 7 | Oct 4 |
Frost dates near Saint Regis
- De Borgia, MT 59830 · last —, first —
- Haugan, MT 59842 · last —, first —
- Plains, MT 59859 · last —, first —
- Saltese, MT 59867 · last —, first —
- Superior, MT 59872 · last May 17, first Sep 23
- Paradise, MT 59856 · last —, first —
- Thompson Falls, MT 59873 · last May 7, first Oct 4
- Hot Springs, MT 59845 · last May 10, first Oct 5
Frequently asked questions
- When is the last frost in Saint Regis, MT?
- Frost is possible in any month at the nearest NOAA station (Haugan 1 W, MT), so there is no reliable average last frost date.
- When is the first frost in Saint Regis, MT?
- Frost is possible in any month at the nearest NOAA station.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.