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Will it freeze in Butte in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 27°F (Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST).
Tonight: forecast low 27°F. Hard freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
7 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 27°F Hard freeze · Mostly Clear
- Fri, Nov 6 33°F Frost possible · Mostly Cloudy
- Sat, Nov 7 35°F Frost possible · Partly Cloudy
- Sun, Nov 8 32°F Freeze · Mostly Cloudy
- Mon, Nov 9 34°F Frost possible · Partly Cloudy
- Tue, Nov 10 35°F Frost possible · Partly Cloudy
- Wed, Nov 11 35°F Frost possible · 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 Butte
The median first fall hard-freeze date (28°F) is September 17, from NOAA’s 1991–2020 Climate Normals at Butte Bert Mooney Airport. 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 | rare in most years | rare in most years | 49 days |
| 32°F freeze | May 27 · Jun 13 · Jul 1 | Aug 24 · Sep 5 · Sep 19 | 83 days |
| 28°F hard freeze | May 8 · May 21 · Jun 10 | Sep 2 · Sep 17 · Oct 1 | 117 days |
Average high temperature by month
1991–2020 normals at Butte Bert Mooney Airport
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 Butte, MT come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Butte Bert Mooney Airport (station USW00024135, elevation 5,506 ft), 9.0 mi from Butte. 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 Butte
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Anaconda, MT | 27 mi | Jun 1 | Sep 14 |
| Helena, MT | 57 mi | May 9 | Sep 30 |
| Belgrade, MT | 71 mi | May 26 | Sep 16 |
| Hamilton, MT | 76 mi | May 21 | Sep 22 |
| Bozeman, MT | 79 mi | May 26 | Sep 22 |
| Missoula, MT | 94 mi | May 10 | Oct 1 |
| Livingston, MT | 103 mi | May 27 | Sep 14 |
| Great Falls, MT | 129 mi | May 6 | Oct 1 |
| Polson, MT | 142 mi | May 10 | Oct 5 |
| Rexburg, ID | 150 mi | May 12 | Sep 24 |
Frequently asked questions
When is the last frost in Butte?
On average, the last spring frost (32°F) in Butte is around June 13. In about 1 year in 10 it comes after July 1, and in 9 years in 10 it comes after May 27.
When is the first frost in Butte?
The first fall frost (32°F) usually arrives around September 5. There’s a 10% chance of a freeze by August 24 and a 90% chance by September 19.
What growing zone is Butte?
Butte is in USDA Plant Hardiness Zone 5a (average annual extreme minimum temperature −20 to −15°F), based on the 2023 USDA map for ZIP code 59750. See growing zones in Montana.
More: all Montana frost dates · Montana growing zones · UV index today in Butte · frost vs. freeze