Grass Range, MT Weather & Growing Conditions
Tonight
54°F
Slight Chance Showers And Thunderstorms then Light Rain Likely
A slight chance of showers and thunderstorms before midnight, then rain likely. Cloudy, with a low around 54. North wind around 8 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 54°F | Slight Chance Showers And Thunderstorms then Light Rain Likely | 8 mph N | 58% |
| Saturday | 59°F | Rain Likely then Showers And Thunderstorms Likely | 12 mph N | 70% |
| Saturday Night | 52°F | Rain | 6 to 9 mph N | 79% |
| Sunday | 62°F | Light Rain Likely | 7 mph NNE | 72% |
| Sunday Night | 49°F | Mostly Cloudy | 7 mph SE | 9% |
| Monday | 73°F | Mostly Sunny | 6 to 13 mph SSE | 0% |
| Monday Night | 51°F | Mostly Clear | 8 to 12 mph S | 0% |
| Tuesday | 78°F | Mostly Sunny | 6 mph W | 0% |
| Tuesday Night | 54°F | Partly Cloudy | 7 mph S | 2% |
| Wednesday | 78°F | Sunny | 7 mph SW | 3% |
| Wednesday Night | 54°F | Mostly Clear | 8 mph S | 1% |
| Thursday | 79°F | Sunny | 6 to 10 mph S | 3% |
| Thursday Night | 55°F | Partly Cloudy | 9 mph S | 3% |
| Friday | 80°F | Mostly Sunny | 7 to 10 mph SSW | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Grass Range, MT
Last spring frost
May 20
First fall frost
Sep 24
Growing season
126 days
Hardiness zone
4b
Explore more for Grass Range, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Grass Range, Mt (4.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.