Forty Mile Colony, MT Weather & Growing Conditions
Today
62°F
Showers And Thunderstorms
Showers and thunderstorms. Cloudy. High near 62, with temperatures falling to around 60 in the afternoon. Northwest wind around 10 mph. Chance of precipitation is 90%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 62°F | Showers And Thunderstorms | 10 mph NW | 92% |
| Tonight | 48°F | Patchy Fog | 12 mph NW | 88% |
| Sunday | 62°F | Rain Showers | 12 mph WNW | 81% |
| Sunday Night | 46°F | Chance Rain Showers then Mostly Cloudy | 2 to 6 mph WSW | 32% |
| Monday | 71°F | Mostly Sunny | 5 mph SE | 3% |
| Monday Night | 47°F | Mostly Clear | 5 to 8 mph SSE | 0% |
| Tuesday | 79°F | Sunny | 6 mph ENE | 0% |
| Tuesday Night | 50°F | Mostly Clear then Slight Chance Rain Showers | 5 mph SE | 15% |
| Wednesday | 79°F | Mostly Sunny | 6 mph ESE | 5% |
| Wednesday Night | 51°F | Partly Cloudy | 2 to 6 mph SSE | 4% |
| Thursday | 82°F | Sunny | 6 mph ESE | 1% |
| Thursday Night | 51°F | Mostly Clear | 3 to 8 mph SE | 1% |
| Friday | 82°F | Mostly Sunny | 3 to 7 mph S | 1% |
| Friday Night | 51°F | Partly Cloudy | 2 to 7 mph SSE | 9% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Forty Mile Colony, MT
Last spring frost
May 21
First fall frost
Sep 17
Growing season
117 days
Hardiness zone
5a
Explore more for Forty Mile Colony, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Wyola 1 Sw, Mt (10.1 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.