Butte, Montana climate: Normal weather by month, frost dates and records
Butte's normal year runs from 7°F December nights to 81°F July afternoons, with 12.8 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 4.5°C, December lows of −14°C, July highs of 27°C, 324 mm of precipitation a year.
- NOAA stationButte Bert Mooney Airport
- Station IDUSW00024135
- Location45.96°N 112.50°W
- Elevation5,506 ft (1,678 m)
- Population35,480
On October 14, the normal high in Butte is 55°F and the normal low 28°F, and the chance of measurable rain or snow is 26%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Butte.
- Jan 32° 8°
- Feb 35° 10°
- Mar 44° 19°
- Apr 51° 26°
- May 61° 34°
- Jun 70° 41°
- Jul 81° 46°
- Aug 80° 44°
- Sep 69° 37°
- Oct 54° 27°
- Nov 40° 16°
- Dec 31° 7°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Butte each month?
July is the warmest month, with normal highs of 81°F; December the coldest, with normal lows of 7°F. The most precipitation falls in June (2.45 in), the least in January (0.42 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 32°F | 8°F | 20.0°F | 0.42 | 7 | <1 | 31 | 9 h |
| February | 35°F | 10°F | 22.2°F | 0.43 | 7 | <1 | 27 | 10 h 20 min |
| March | 44°F | 19°F | 31.6°F | 0.64 | 9 | <1 | 30 | 11 h 50 min |
| April | 51°F | 26°F | 38.7°F | 1.33 | 11 | <1 | 25 | 13 h 30 min |
| May | 61°F | 34°F | 47.6°F | 2.02 | 13 | <1 | 12 | 14 h 50 min |
| June | 70°F | 41°F | 55.5°F | 2.45 | 14 | <1 | 2 | 15 h 40 min |
| July | 81°F | 46°F | 63.6°F | 1.20 | 9 | 4 | <1 | 15 h 30 min |
| August | 80°F | 44°F | 61.8°F | 1.28 | 8 | 3 | 1 | 14 h 10 min |
| September | 69°F | 37°F | 52.8°F | 1.07 | 7 | <1 | 9 | 12 h 40 min |
| October | 54°F | 27°F | 40.6°F | 0.84 | 8 | <1 | 24 | 11 h |
| November | 40°F | 16°F | 27.8°F | 0.60 | 8 | <1 | 29 | 9 h 30 min |
| December | 31°F | 7°F | 19.0°F | 0.48 | 7 | <1 | 31 | 8 h 40 min |
| Year (annual) | 54°F | 26°F | 40.1°F | 12.76 | 107 | 8 | 220 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 0°C | −13°C | −6.7°C | 11 mm |
| February | 1°C | −12°C | −5.4°C | 11 mm |
| March | 7°C | −7°C | −0.2°C | 16 mm |
| April | 11°C | −3°C | 3.7°C | 34 mm |
| May | 16°C | 1°C | 8.7°C | 51 mm |
| June | 21°C | 5°C | 13.1°C | 62 mm |
| July | 27°C | 8°C | 17.6°C | 30 mm |
| August | 27°C | 7°C | 16.6°C | 33 mm |
| September | 21°C | 3°C | 11.6°C | 27 mm |
| October | 12°C | −3°C | 4.8°C | 21 mm |
| November | 5°C | −9°C | −2.3°C | 15 mm |
| December | −1°C | −14°C | −7.2°C | 12 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Divide (19 miles away), gets 15 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024135; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Butte?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, September has the fewest days with rain (7).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024135.
When is the last frost in Butte?
In Butte, the last spring frost (32°F) comes after June 13 in half of years and after July 1 in one year in ten; the first autumn frost comes before September 5 in half of years and before August 24 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- June 131 year in 10 after July 1; 9 in 10 after May 27
- First autumn frost, half of years before
- September 51 year in 10 before August 24; 9 in 10 before September 19
NOAA puts the median frost-free season at 83 days, and the season without a hard freeze (28°F) at 117 days.
A hard freeze (28°F) comes after May 21 in half of springs and before September 17 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Butte in zones 4b to 5a across its 5 ZIP code areas (5a in 59701, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Butte's NOAA station is in zone 4a: the coldest night of a typical year reaches −28°F (29 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Montana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00024135; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Butte ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Butte's 5 ZIP code areas run from zone 4b to 5a: 1 in 4b and 4 in 5a. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Butte?
In a normal year in Butte, 8 days a year reach 90°F, 220 nights fall to 32°F or colder and 107 days bring measurable precipitation.
- Days at 90°F or more
- 8a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 220a normal year
- Days that stay below freezing
- 54high of 32°F or less
- Days with 0.01 inch of precipitation
- 107a normal year
The highest temperature in this station's record (since 1894) is 99°F, on July 22, 1936; the lowest is −52°F, on February 9, 1933.
The wettest calendar year on that record is 1909, with 20.55 in; the snowiest season is 1926–27, with 115.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00024135; records: ACIS (NOAA Regional Climate Centers), station USW00024135. Records use complete months only; a month missing more than three days is left out.
How sunny is Butte?
Over a year 76% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Butte, 4.2 kWh per square metre a day. July is the sunniest month (85%) and December the cloudiest (65%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 70% | 1.7 |
| February | 73% | 2.8 |
| March | 73% | 4.0 |
| April | 70% | 5.1 |
| May | 70% | 5.9 |
| June | 76% | 6.8 |
| July | 85% | 7.3 |
| August | 84% | 6.2 |
| September | 80% | 4.7 |
| October | 73% | 3.0 |
| November | 68% | 1.9 |
| December | 65% | 1.4 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Butte need?
A normal year in Butte brings 9,129 heating degree days, 70% more than the median U.S. place (5,373), and 83 cooling degree days, 91% fewer than the median (908). Nine months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,210 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,395 | 0 |
| February | 1,198 | 0 |
| March | 1,037 | 0 |
| April | 787 | 0 |
| May | 538 | 0 |
| June | 290 | 6 |
| July | 91 | 48 |
| August | 124 | 27 |
| September | 368 | 2 |
| October | 758 | 0 |
| November | 1,115 | 0 |
| December | 1,427 | 0 |
| Year (annual) | 9,129 | 83 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024135. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Butte been warmer than normal lately?
2024 averaged 42.0°F, 1.9°F above the 1991-2020 normal of 40.1°F. 2 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 41.8°F | +1.7°F | 6.49 |
| 2022 | 39.8°F | −0.3°F | 9.66 |
| 2023 | 39.8°F | −0.3°F | 18.00 |
| 2024 | 42.0°F | +1.9°F | 7.87 |
Over 115 complete years from 1895 to 2025, the station's annual mean temperature rose at a fitted 0.7°F per century (+0.04°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00024135; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Butte's climate compare?
Butte is warmer than 15 of the other 140 places with their own NOAA record in Montana, and wetter than 27. Across the 7,247 U.S. stations with normals, its annual mean of 40.1°F is warmer than 6%.
In the Köppen classification computed from these normals, Butte is BSk: cold semi-arid steppe. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Butte share this climate record?
3 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Whitehall, MT1,116 people · 20 mi E
- Walkerville, MT654 people · 5 mi N
- Rader Creek, MT373 people · 12 mi SE
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Butte's climate
What is the coldest month in Butte?
December, with a normal high of 31°F and a normal low of 7°F. The warmest is July (81°F by day, 46°F at night).
Does it snow in Butte?
Yes. NOAA publishes no 1991-2020 snowfall normal for Butte's NOAA station; the nearest record that keeps one, Divide (19 miles away), records 15 inches of snow in a normal year.
What is the rainiest month in Butte?
June, with 2.45 in of precipitation in a normal year; the driest is January with 0.42 in.
What plant hardiness zone is Butte in?
The USDA's 2023 map puts Butte in zones 4b to 5a across its 5 ZIP code areas (5a in 59701, the largest). By the same method at Butte's NOAA station, the coldest night of a typical year reaches −28°F (29 years, 1991-2020): zone 4a.
How late can frost come in Butte?
In half of years the last 32°F night comes after June 13; in one year in ten it comes after July 1. Waiting until July 1 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Montana climateThe statewide normals and every place in the state
- Divide, MT19 miles from this station, 40.9°F a year
- Anaconda, MT24 miles from this station, 43.8°F a year
- Boulder, MT26 miles from this station, 42.6°F a year
- Wise River (3 mi WNW), MT26 miles from this station, 37.7°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made