St. Marie, MT Weather & Growing Conditions
Overnight
53°F
Mostly Cloudy
Mostly cloudy, with a low around 53. Northeast wind around 14 mph, with gusts as high as 21 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 53°F | Mostly Cloudy | 14 mph NE | 0% |
| Saturday | 67°F | Mostly Cloudy | 16 mph NE | 0% |
| Saturday Night | 49°F | Mostly Cloudy then Slight Chance Rain Showers | 14 mph E | 18% |
| Sunday | 62°F | Patchy Fog then Mostly Cloudy | 15 mph ESE | 23% |
| Sunday Night | 47°F | Partly Cloudy | 13 mph SE | 0% |
| Monday | 69°F | Mostly Sunny | 12 to 16 mph SE | 1% |
| Monday Night | 49°F | Mostly Clear | 16 mph SE | 0% |
| Tuesday | 75°F | Sunny | 13 mph SSE | 0% |
| Tuesday Night | 52°F | Mostly Clear | 6 to 9 mph SE | 1% |
| Wednesday | 78°F | Sunny | 9 mph SE | 3% |
| Wednesday Night | 53°F | Mostly Clear | 6 to 9 mph SE | 5% |
| Thursday | 79°F | Sunny | 10 mph SE | 1% |
| Thursday Night | 53°F | Mostly Clear | 7 to 12 mph ESE | 4% |
| Friday | 78°F | Sunny | 12 to 16 mph SE | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for St. Marie, MT
Last spring frost
May 13
First fall frost
Sep 27
Growing season
134 days
Hardiness zone
4a
Explore more for St. Marie, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, St Marie, Mt (1.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.