Harman US

Fort Smith, MT Weather & Growing Conditions

Overnight
54°F
Showers And Thunderstorms
Showers and thunderstorms before 3am, then patchy fog and a chance of showers and thunderstorms. Mostly cloudy. Low around 54, with temperatures rising to around 56 overnight. Northwest wind around 5 mph. Chance of precipitation is 90%.

7-day forecast

WhenTempForecastWindPrecip
Overnight 54°F Showers And Thunderstorms 5 mph NW 90%
Saturday 60°F Patchy Fog 5 to 12 mph NNW 93%
Saturday Night 48°F Patchy Fog 10 to 15 mph NW 86%
Sunday 60°F Rain Showers 12 mph WNW 88%
Sunday Night 47°F Chance Rain Showers then Mostly Cloudy 3 to 7 mph WSW 28%
Monday 69°F Mostly Sunny 5 mph SE 5%
Monday Night 49°F Mostly Clear 7 mph SSE 0%
Tuesday 75°F Sunny 5 mph NE 0%
Tuesday Night 53°F Partly Cloudy then Slight Chance Rain Showers 6 mph S 15%
Wednesday 77°F Mostly Sunny 6 mph WNW 7%
Wednesday Night 53°F Partly Cloudy 5 to 9 mph S 5%
Thursday 79°F Sunny 5 to 8 mph SW 1%
Thursday Night 53°F Mostly Clear 3 to 8 mph SSE 1%
Friday 79°F Mostly Sunny 7 mph SW 0%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Fort Smith, MT

Last spring frost
May 7
First fall frost
Oct 5
Growing season
151 days
Hardiness zone
5a

Explore more for Fort Smith, MT: full frost dates · planting calendar · Montana frost dates

Climate data from the nearest NOAA station, Yellowtail Dam, Mt (0.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.