Westby, MT Weather & Growing Conditions
Today
50°F
Sunny
Sunny. High near 50, with temperatures falling to around 42 in the afternoon. North northwest wind 6 to 9 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 50°F | Sunny | 6 to 9 mph NNW | 0% |
| Tonight | 26°F | Partly Cloudy | 3 to 8 mph NE | 0% |
| Thursday | 46°F | Partly Sunny | 5 to 13 mph SSE | 0% |
| Thursday Night | 31°F | Partly Cloudy | 9 mph SSW | 0% |
| Friday | 51°F | Sunny | 9 to 14 mph WSW | 0% |
| Friday Night | 34°F | Partly Cloudy | 9 to 17 mph SW | 0% |
| Saturday | 54°F | Mostly Sunny | 9 to 21 mph W | 0% |
| Saturday Night | 30°F | Partly Cloudy | 6 to 9 mph WSW | 0% |
| Sunday | 58°F | Mostly Sunny | 7 to 15 mph SSW | 0% |
| Sunday Night | 38°F | Partly Cloudy | 12 to 17 mph W | 0% |
| Monday | 53°F | Mostly Sunny | 8 to 18 mph WNW | 0% |
| Monday Night | 31°F | Partly Cloudy | 8 mph WSW | 2% |
| Tuesday | 53°F | Mostly Sunny | 6 to 10 mph SSW | 2% |
| Tuesday Night | 34°F | Partly Cloudy | 8 mph SW | 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 Nov 4, 2026.