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Will it freeze in Miles City in the next 7 nights?
No overnight lows at or below 32°F are forecast in Miles City during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 33°F. Frost possible.
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 33°F Frost possible · Partly Cloudy
- Fri, Nov 6 36°F Frost possible · Partly Cloudy
- Sat, Nov 7 36°F Frost possible · Mostly Clear
- Sun, Nov 8 37°F Above 36°F · Mostly Cloudy
- Mon, Nov 9 35°F Frost possible · Mostly Cloudy
- Tue, Nov 10 39°F Above 36°F · Mostly Clear
- Wed, Nov 11 38°F Above 36°F · Partly Cloudy
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 Miles City
The median first fall hard-freeze date (28°F) is October 8, from NOAA’s 1991–2020 Climate Normals at Miles City F Wiley Field. 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 7 · May 18 · May 31 | Sep 10 · Sep 23 · Oct 4 | 124 days |
| 32°F freeze | Apr 26 · May 8 · May 21 | Sep 17 · Sep 30 · Oct 14 | 144 days |
| 28°F hard freeze | Apr 13 · Apr 29 · May 12 | Sep 25 · Oct 8 · Oct 23 | 163 days |
Average high temperature by month
1991–2020 normals at Miles City F Wiley Field
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 Miles City, MT come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Miles City F Wiley Field (station USW00024037, elevation 2,624 ft), 2.5 mi from Miles City. 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 Miles City
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Sidney, MT | 120 mi | May 11 | Sep 27 |
| Sheridan, WY | 124 mi | May 21 | Sep 23 |
| Billings, MT | 137 mi | May 4 | Oct 7 |
| Dickinson, ND | 148 mi | May 20 | Sep 22 |
| Gillette, WY | 149 mi | May 15 | Oct 1 |
| Laurel, MT | 150 mi | May 5 | Oct 3 |
| Belle Fourche, SD | 154 mi | May 10 | Sep 30 |
| Watford City, ND | 155 mi | May 9 | Sep 27 |
| Williston, ND | 160 mi | May 21 | Sep 21 |
| Spearfish, SD | 165 mi | May 12 | Oct 2 |
Frequently asked questions
When is the last frost in Miles City?
On average, the last spring frost (32°F) in Miles City is around May 8. In about 1 year in 10 it comes after May 21, and in 9 years in 10 it comes after April 26.
When is the first frost in Miles City?
The first fall frost (32°F) usually arrives around September 30. There’s a 10% chance of a freeze by September 17 and a 90% chance by October 14.
Can it frost in Miles City 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 18.
What growing zone is Miles City?
Miles City is in USDA Plant Hardiness Zone 4b (average annual extreme minimum temperature −25 to −20°F), based on the 2023 USDA map for ZIP code 59301. See growing zones in Montana.
More: all Montana frost dates · Montana growing zones · frost vs. freeze