# Frost dates for Great Falls, MT (59404)

**Do this (Safe, 2026-11-02):** Frost season started Sep 17. Keep covers ready for cold nights.

| Risk | Last spring frost | First fall frost | Frost-free days |
|---|---|---|---|
| Safe (1 in 10 years later) | May 19 | Sep 17 | 121 |
| Median | May 6 | Oct 1 | 148 |
| Bold (9 in 10 years later) | Apr 23 | Oct 16 | 176 |

Frost = 32°F. Station: Great Falls 16ST, MT, 1 mi away.

## Next nights (NWS overnight low)

- 2026-11-01: 34°F — Cover (tonight)
- 2026-11-02: 32°F — Cover
- 2026-11-03: 32°F — Cover
- 2026-11-04: 32°F — Cover
- 2026-11-05: 36°F — Cover
- 2026-11-06: 35°F — Cover
- 2026-11-07: 36°F — Cover

Go above 40°F · Wait 37–40°F · Cover 36°F or less · Freeze 28°F or less.

Source: Frost dates: NOAA NCEI U.S. Climate Normals 1991–2020, station Great Falls 16ST, MT (1 mi, 105 ft higher than you). Not endorsed by NOAA. Nights: National Weather Service.

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