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Will it freeze in Belle Fourche in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 30°F (Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST).
Tonight: forecast low 30°F. Freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
4 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 30°F Freeze · Partly Cloudy
- Fri, Nov 6 34°F Frost possible · Mostly Clear
- Sat, Nov 7 35°F Frost possible · Mostly Clear
- Sun, Nov 8 39°F Above 36°F · Mostly Clear
- Mon, Nov 9 35°F Frost possible · Partly Cloudy
- Tue, Nov 10 39°F Above 36°F · Partly Cloudy
- Wed, Nov 11 40°F Above 36°F · Mostly Clear
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Belle Fourche
The median first fall hard-freeze date (28°F) is October 10, from NOAA’s 1991–2020 Climate Normals at Belle Fourche. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | May 8 · May 21 · Jun 4 | Sep 8 · Sep 21 · Oct 4 | 122 days |
| 32°F freeze | Apr 27 · May 10 · May 25 | Sep 16 · Sep 30 · Oct 13 | 143 days |
| 28°F hard freeze | Apr 14 · Apr 30 · May 15 | Sep 23 · Oct 10 · Oct 24 | 163 days |
Average high temperature by month
1991–2020 normals at Belle Fourche
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Belle Fourche, SD come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Belle Fourche (station USC00390559, elevation 3,020 ft), 0.7 mi from Belle Fourche. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Belle Fourche
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Spearfish, SD | 12 mi | May 12 | Oct 2 |
| Sturgis, SD | 25 mi | May 8 | Oct 3 |
| Rapid City, SD | 52 mi | May 3 | Oct 8 |
| Box Elder, SD | 54 mi | May 12 | Oct 1 |
| Gillette, WY | 85 mi | May 15 | Oct 1 |
| Douglas, WY | 153 mi | May 19 | Sep 23 |
| Sheridan, WY | 153 mi | May 21 | Sep 23 |
| Miles City, MT | 154 mi | May 8 | Sep 30 |
| Dickinson, ND | 162 mi | May 20 | Sep 22 |
| Casper, WY | 176 mi | May 10 | Sep 29 |
Frequently asked questions
When is the last frost in Belle Fourche?
On average, the last spring frost (32°F) in Belle Fourche is around May 10. In about 1 year in 10 it comes after May 25, and in 9 years in 10 it comes after April 27.
When is the first frost in Belle Fourche?
The first fall frost (32°F) usually arrives around September 30. There’s a 10% chance of a freeze by September 16 and a 90% chance by October 13.
Can it frost in Belle Fourche after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 21.
What growing zone is Belle Fourche?
Belle Fourche is in USDA Plant Hardiness Zone 5b (average annual extreme minimum temperature −15 to −10°F), based on the 2023 USDA map for ZIP code 57779. See growing zones in South Dakota.
More: all South Dakota frost dates · South Dakota growing zones · frost vs. freeze