Big Sky, MT Weather & Growing Conditions
This Afternoon
56°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely before 5pm, then a chance of showers and thunderstorms. Mostly cloudy, with a high near 56. North northwest wind around 6 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 56°F | Showers And Thunderstorms Likely | 6 mph NNW | 69% |
| Tonight | 40°F | Chance Showers And Thunderstorms then Chance Light Rain | 3 to 8 mph NW | 50% |
| Sunday | 63°F | Partly Sunny | 3 to 7 mph NW | 6% |
| Sunday Night | 36°F | Partly Cloudy | 6 mph ENE | 4% |
| Monday | 73°F | Sunny | 3 to 8 mph S | 2% |
| Monday Night | 40°F | Mostly Clear | 5 to 8 mph S | 0% |
| Tuesday | 73°F | Mostly Sunny | 6 to 10 mph S | 1% |
| Tuesday Night | 43°F | Mostly Cloudy | 6 to 10 mph S | 11% |
| Wednesday | 72°F | Mostly Sunny | 13 mph S | 12% |
| Wednesday Night | 43°F | Partly Cloudy | 10 to 16 mph S | 5% |
| Thursday | 75°F | Sunny | 16 mph S | 2% |
| Thursday Night | 45°F | Mostly Clear | 13 to 16 mph SSE | 1% |
| Friday | 74°F | Mostly Sunny | 17 mph S | 2% |
| Friday Night | 43°F | Partly Cloudy | 14 mph SSE | 7% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Big Sky, MT
Last spring frost
Jun 15
First fall frost
Sep 10
Growing season
87 days
Hardiness zone
5a
Explore more for Big Sky, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Hebgen Dam, Mt (13.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.