Westby, MT Weather & Growing Conditions
Tonight
54°F
Slight Chance Rain Showers then Mostly Cloudy
A slight chance of rain showers before 8pm. Mostly cloudy, with a low around 54. North northeast wind around 13 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 54°F | Slight Chance Rain Showers then Mostly Cloudy | 13 mph NNE | 20% |
| Saturday | 66°F | Cloudy | 14 to 17 mph NE | 9% |
| Saturday Night | 49°F | Mostly Cloudy | 14 mph E | 14% |
| Sunday | 62°F | Slight Chance Rain Showers then Mostly Cloudy | 14 mph ESE | 15% |
| Sunday Night | 48°F | Partly Cloudy | 8 to 12 mph SE | 2% |
| Monday | 69°F | Mostly Sunny | 8 to 18 mph SSE | 0% |
| Monday Night | 51°F | Partly Cloudy | 16 mph SSE | 0% |
| Tuesday | 72°F | Mostly Sunny | 15 to 20 mph SSE | 1% |
| Tuesday Night | 53°F | Partly Cloudy | 12 to 16 mph SSE | 3% |
| Wednesday | 76°F | Mostly Sunny | 13 mph S | 5% |
| Wednesday Night | 53°F | Mostly Clear | 9 mph S | 6% |
| Thursday | 77°F | Sunny | 7 to 12 mph SSE | 3% |
| Thursday Night | 54°F | Mostly Clear | 10 mph SE | 4% |
| Friday | 76°F | Mostly Sunny | 12 to 17 mph SSE | 3% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Westby, MT
Last spring frost
May 18
First fall frost
Sep 21
Growing season
125 days
Hardiness zone
3b
Explore more for Westby, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Westby, Mt (4.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.