Climate averages 1991–2020
Missoula weather
in May.
A mild, moderately wet month: the 5th warmest and one of the wettest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a mild month in Missoula: daytime highs average 17.9°C and nights cool to about 6.3°C. By daytime temperature it is the 5th warmest of the 12 months.
Expect about 56 mm of rain on roughly 11 days, which makes May a moderately wet month (one of the wettest months of the year). Daylight, from sunrise to sunset, lasts about 15 h 01 min on an average May day.
The nearest other city in this atlas is Spokane Valley (261 km away). In May its highs average 19.2°C, 1.4°C warmer than Missoula, with 51 mm of rain.
Among the 498 cities listed in the United States, Missoula ranks 474th of 498 for the warmest May highs and joint 151st of 498 for the driest May (rainfall, lowest first). The mean May high of those 498 cities is 23.8°C; Missoula is 5.9°C cooler than that mean.
From May to June, average highs rise by 4.3°C to 22.2°C, and monthly rainfall stays at 56 mm.
The annual picture
May in context
Monthly precipitation
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Missoula climate table
| Month | Average highHigh / low | Average low | Precipitation mm/month | Wet days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 0.6°C-6.9°C | -6.9°C | 45 | 10.8 | 9.09 h |
| February | 2.7°C-5.7°C | -5.7°C | 41 | 9.9 | 10.310 h |
| March | 7.0°C-1.7°C | -1.7°C | 44 | 11.0 | 11.912 h |
| April | 11.4°C1.5°C | 1.5°C | 53 | 11.4 | 13.614 h |
| May, selected | 17.9°C6.3°C | 6.3°C | 56 | 11.0 | 15.015 h |
| June | 22.2°C10.4°C | 10.4°C | 56 | 10.0 | 15.816 h |
| July | 28.8°C15.3°C | 15.3°C | 19 | 4.6 | 15.515 h |
| August | 28.6°C14.9°C | 14.9°C | 19 | 3.8 | 14.214 h |
| September | 22.5°C9.8°C | 9.8°C | 30 | 5.8 | 12.613 h |
| October | 13.6°C3.5°C | 3.5°C | 44 | 8.6 | 10.911 h |
| November | 5.2°C-2.3°C | -2.3°C | 50 | 10.0 | 9.49 h |
| December | -0.1°C-7.4°C | -7.4°C | 51 | 10.4 | 8.69 h |
Precipitation (rain or snow, as water) is the average of the 30 separate monthly totals. A wet day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Spokane Valley in MayUnited States · 261 kmHigh 19.2°C · Low 7.0°C · 51 mm rain
- Spokane in MayUnited States · 274 kmHigh 19.9°C · Low 7.8°C · 46 mm rain
- Lethbridge in MayCanada · 326 kmHigh 17.1°C · Low 5.4°C · 59 mm rain
- Kennewick in MayUnited States · 400 kmHigh 24.8°C · Low 11.4°C · 18 mm rain
- Boise in MayUnited States · 401 kmHigh 21.6°C · Low 8.5°C · 31 mm rain
- Tri-Cities in MayUnited States · 404 kmHigh 25.0°C · Low 11.5°C · 18 mm rain
- Meridian in MayUnited States · 408 kmHigh 21.8°C · Low 8.6°C · 29 mm rain
- Nampa in MayUnited States · 422 kmHigh 22.4°C · Low 9.8°C · 29 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Missoula) is explained once on the Missoula year overview and on the Sources, method and limits page.