Plains, MT
Climate overview — based on NOAA 1991-2020 normals from SAINT REGIS 1 NE, MT US.
Year-round temperatures (°F)
Avg high
Avg low
Climate summary
Plains has an annual average temperature of 46.2°F with about 0 inches of precipitation per year. The warmest month is August (average high 86.7°F), and the coldest is December (average low 20.9°F).
Annual swing
39.7°F
warmest to coldest month
Best time to visit Plains
Full guide →Climate change signal
All-time records →0 of 366 (0%) of Plains's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1960s | 121 | |
| 1970s | 69 | |
| 1980s | 55 | |
| 1990s | 64 | |
| 2000s | 52 | |
| 2010s | 5 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 35.0°F | 21.5°F | 28.3°F | in | — | — |
| February | 41.0°F | 21.4°F | 31.2°F | in | — | — |
| March | 50.6°F | 26.3°F | 38.4°F | in | — | — |
| April | 59.0°F | 31.5°F | 45.2°F | in | — | — |
| May | 69.0°F | 38.3°F | 53.6°F | in | — | — |
| June | 76.5°F | 44.1°F | 60.3°F | in | — | — |
| July | 86.4°F | 47.2°F | 66.8°F | in | — | — |
| August | 86.7°F | 45.3°F | 66.0°F | in | — | — |
| September | 76.0°F | 39.4°F | 57.7°F | in | — | — |
| October | 58.5°F | 32.1°F | 45.3°F | in | — | — |
| November | 41.8°F | 26.4°F | 34.1°F | in | — | — |
| December | 33.3°F | 20.9°F | 27.1°F | in | — | — |
Last spring / first fall frost
All-time recordsHottest, coldest, wettest
Planting calendarWhat to plant, and when