Missoula, Montana climate: Normal weather by month, frost dates and records
Missoula's normal year runs from 18°F December nights to 85°F July afternoons, with 14.1 inches of precipitation and 43 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.3°C, December lows of −8°C, July highs of 30°C, 358 mm of precipitation a year.
- NOAA stationMissoula International Airport
- Station IDUSW00024153
- Location46.92°N 114.09°W
- Elevation3,192 ft (973 m)
- From the center4 miles
- Population78,204
On October 23, the normal high in Missoula is 51°F and the normal low 30°F, and the chance of measurable rain or snow is 34%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Missoula.
- Jan 32° 18°
- Feb 37° 21°
- Mar 48° 27°
- Apr 56° 32°
- May 66° 40°
- Jun 73° 46°
- Jul 85° 52°
- Aug 84° 50°
- Sep 73° 42°
- Oct 56° 32°
- Nov 40° 25°
- Dec 31° 18°
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 Missoula each month?
July is the warmest month, with normal highs of 85°F; December the coldest, with normal lows of 18°F. The most precipitation falls in June (2.14 in), the least in August (0.83 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 32°F | 18°F | 24.8°F | 0.96 | 9.9 | 13 | <1 | 30 | 8 h 50 min |
| February | 37°F | 21°F | 29.0°F | 0.88 | 8.5 | 11 | <1 | 26 | 10 h 20 min |
| March | 48°F | 27°F | 37.4°F | 0.92 | 5.0 | 11 | <1 | 25 | 11 h 50 min |
| April | 56°F | 32°F | 44.2°F | 1.36 | 1.3 | 11 | <1 | 15 | 13 h 30 min |
| May | 66°F | 40°F | 53.0°F | 1.77 | 0.3 | 12 | <1 | 4 | 15 h |
| June | 73°F | 46°F | 59.7°F | 2.14 | 0.0 | 13 | 2 | <1 | 15 h 50 min |
| July | 85°F | 52°F | 68.4°F | 0.85 | 0.0 | 6 | 12 | <1 | 15 h 30 min |
| August | 84°F | 50°F | 67.2°F | 0.83 | 0.0 | 6 | 11 | <1 | 14 h 20 min |
| September | 73°F | 42°F | 57.5°F | 0.96 | 0.1 | 7 | 1 | 2 | 12 h 40 min |
| October | 56°F | 32°F | 44.1°F | 1.18 | 0.9 | 10 | <1 | 15 | 11 h |
| November | 40°F | 25°F | 32.3°F | 1.18 | 5.4 | 11 | <1 | 26 | 9 h 30 min |
| December | 31°F | 18°F | 24.4°F | 1.08 | 11.6 | 13 | <1 | 30 | 8 h 30 min |
| Year (annual) | 57°F | 34°F | 45.2°F | 14.11 | 43.0 | 124 | 27 | 173 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −8°C | −4.0°C | 24 mm | 25 cm |
| February | 3°C | −6°C | −1.7°C | 22 mm | 22 cm |
| March | 9°C | −3°C | 3.0°C | 23 mm | 13 cm |
| April | 13°C | 0°C | 6.8°C | 35 mm | 3 cm |
| May | 19°C | 4°C | 11.7°C | 45 mm | 1 cm |
| June | 23°C | 8°C | 15.4°C | 54 mm | 0 cm |
| July | 30°C | 11°C | 20.2°C | 22 mm | 0 cm |
| August | 29°C | 10°C | 19.6°C | 21 mm | 0 cm |
| September | 23°C | 6°C | 14.2°C | 24 mm | 0 cm |
| October | 13°C | 0°C | 6.7°C | 30 mm | 2 cm |
| November | 4°C | −4°C | 0.2°C | 30 mm | 14 cm |
| December | −1°C | −8°C | −4.2°C | 27 mm | 29 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024153; 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 Missoula?
Normal highs sit between 65°F and 85°F in May, June, August and September. Of those, August has the fewest days with rain (6).
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 USW00024153.
When is the last frost in Missoula?
In Missoula, the last spring frost (32°F) comes after May 16 in half of years and after June 1 in one year in ten; the first autumn frost comes before September 26 in half of years and before September 12 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
- May 161 year in 10 after June 1; 9 in 10 after May 3
- First autumn frost, half of years before
- September 261 year in 10 before September 12; 9 in 10 before October 8
NOAA puts the median frost-free season at 130 days, and the season without a hard freeze (28°F) at 156 days.
A hard freeze (28°F) comes after May 2 in half of springs and before October 6 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Missoula in zone 5b across its 3 ZIP code areas (5b in 59802, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Missoula's NOAA station is in zone 5b: the coldest night of a typical year reaches −11°F (30 complete years).
Frost dates for every NOAA station in Montana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00024153; 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 Missoula ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Missoula's 3 ZIP code areas are all in zone 5b. 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 Missoula?
In a normal year in Missoula, 27 days a year reach 90°F (2 of them 100°F or more), 173 nights fall to 32°F or colder and 124 days bring measurable precipitation.
- Days at 90°F or more
- 27a normal year
- Days at 100°F or more
- 2a normal year
- Nights at 32°F or colder
- 173a normal year
- Days that stay below freezing
- 43high of 32°F or less
- Days with 0.01 inch of precipitation
- 124a normal year
- Days with 1 inch of snow or more
- 14a normal year
The highest temperature in Missoula's official record (kept by the National Weather Service since 1893) is 107°F, on July 6, 2007; the lowest is −33°F, on January 26, 1957.
The wettest calendar year on that record is 1998, with 21.81 in; the snowiest season is 1996–97, with 111.2 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00024153; records: ACIS (NOAA Regional Climate Centers), NWS threaded record MSOthr. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Missoula, and how clear are its skies?
The summer (June-August) dew point averages 43°F. The muggiest month is June, with an average dew point of 45°F; the driest air comes in December (19°F). April is the windiest month (6.6 mph on average), and July has the most clear or nearly clear hours (85%).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 21°F | 79% | 68% | 3.8 mph | 34% | 52% |
| February | 21°F | 70% | 53% | 5.3 mph | 37% | 45% |
| March | 28°F | 62% | 41% | 5.9 mph | 37% | 41% |
| April | 32°F | 56% | 36% | 6.6 mph | 48% | 32% |
| May | 42°F | 59% | 38% | 6.2 mph | 51% | 29% |
| June | 45°F | 51% | 29% | 6.0 mph | 73% | 13% |
| July | 44°F | 42% | 22% | 5.9 mph | 85% | 6% |
| August | 41°F | 48% | 26% | 5.2 mph | 75% | 12% |
| September | 36°F | 58% | 34% | 4.7 mph | 67% | 21% |
| October | 29°F | 73% | 53% | 4.0 mph | 46% | 40% |
| November | 21°F | 79% | 67% | 3.9 mph | 33% | 55% |
| December | 19°F | 81% | 73% | 3.7 mph | 26% | 60% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00024153. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Missoula?
Over a year 71% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Missoula, 3.8 kWh per square metre a day. July is the sunniest month (89%) and December the cloudiest (52%). Among the 459 U.S. places of 50,000 or more, that ranks tied 416th (with 11 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 56% | 1.3 |
| February | 58% | 2.0 |
| March | 59% | 3.1 |
| April | 64% | 4.4 |
| May | 68% | 5.6 |
| June | 73% | 6.4 |
| July | 89% | 7.4 |
| August | 86% | 6.2 |
| September | 79% | 4.4 |
| October | 67% | 2.6 |
| November | 56% | 1.4 |
| December | 52% | 1.0 |
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 Missoula need?
A normal year in Missoula brings 7,514 heating degree days, 40% more than the median U.S. place (5,373), and 306 cooling degree days, 66% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,843 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,246 | 0 |
| February | 1,009 | 0 |
| March | 857 | 0 |
| April | 624 | 0 |
| May | 375 | 3 |
| June | 185 | 28 |
| July | 39 | 146 |
| August | 47 | 115 |
| September | 240 | 15 |
| October | 649 | 0 |
| November | 983 | 0 |
| December | 1,260 | 0 |
| Year (annual) | 7,514 | 306 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00024153. 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 Missoula been warmer than normal lately?
2025 averaged 47.8°F, 2.6°F above the 1991-2020 normal of 45.2°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 47.5°F | +2.3°F | 11.99 | 39.4 |
| 2022 | 45.8°F | +0.6°F | 10.96 | 51.7 |
| 2023 | 47.5°F | +2.3°F | 13.82 | 30.4 |
| 2024 | 47.5°F | +2.3°F | 10.66 | 19.1 |
| 2025 | 47.8°F | +2.6°F | 14.30 | 50.5 |
Over 120 complete years from 1886 to 2025, the station's annual mean temperature rose at a fitted 1.6°F per century (+0.09°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00024153; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Missoula's climate compare?
Missoula is warmer than 96 of the other 140 places with their own NOAA record in Montana, and wetter than 50. Across the 7,247 U.S. stations with normals, its annual mean of 45.2°F is warmer than 20%.
In the Köppen classification computed from these normals, Missoula is Dfb: continental, no dry season, warm summer. 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 Missoula share this climate record?
8 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.
- Orchard Homes, MT5,280 people · 5 mi S
- Lolo, MT4,378 people · 10 mi S
- East Missoula, MT2,072 people · 7 mi SE
- Frenchtown, MT1,629 people · 10 mi NW
- Bonner-West Riverside, MT1,445 people · 10 mi E
- Wye, MT1,222 people · 3 mi NW
- Piltzville, MT605 people · 12 mi E
- Evaro, MT479 people · 11 mi N
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Missoula's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Missoula. This page uses Missoula International Airport; the others differ by site and elevation:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Missoula (2 mi NE) USC00245735 | 3 mi NE | 3,420 ft | 46.2°F | 20°F | 85°F | 17.4 | 50 | May 10 |
| Missoula 6 NW Weather Office USC00245740 | 5 mi NW | 3,197 ft | 46.3°F | 19°F | 86°F | 14.4 | 43 | May 6 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Missoula's climate
What is the coldest month in Missoula?
December, with a normal high of 31°F and a normal low of 18°F. The warmest is July (85°F by day, 52°F at night).
Does it snow in Missoula?
Yes: 43 inches in a normal year, falling on 40 days with 0.1 inch or more, the most in December (11.6 inches).
What is the rainiest month in Missoula?
June, with 2.14 in of precipitation in a normal year; the driest is August with 0.83 in.
What plant hardiness zone is Missoula in?
The USDA's 2023 map puts Missoula in zone 5b across its 3 ZIP code areas (5b in 59802, the largest). By the same method at Missoula's NOAA station, the coldest night of a typical year reaches −11°F (30 years, 1991-2020): zone 5b.
How late can frost come in Missoula?
In half of years the last 32°F night comes after May 16; in one year in ten it comes after June 1. Waiting until June 1 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Missoula in OctoberThis month day by day, its records and recent years
- Montana climateThe statewide normals and every place in the state
- Alberton, MT19 miles from this station, 45.4°F a year
- Potomac, MT25 miles from this station, 39.3°F a year
- St. Ignatius, MT27 miles from this station, 47.7°F a year
- Stevensville, MT28 miles from this station, 45.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made