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Basin, MT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Basin, a community in Jefferson County, Montana.

Today
49°F
Showers And Thunderstorms
Showers and thunderstorms. Cloudy, with a high near 49. East northeast wind around 8 mph. Chance of precipitation is 100%. New rainfall amounts between a quarter and half of an inch possible.

7-day forecast for Basin

WhenTempForecastWindPrecip
Today 49°F Showers And Thunderstorms 8 mph ENE 100%
Tonight 39°F Chance Light Rain then Mostly Cloudy 1 to 5 mph NNE 25%
Sunday 62°F Mostly Sunny 2 to 6 mph WNW 0%
Sunday Night 41°F Mostly Clear 3 mph SW 0%
Monday 67°F Sunny 3 to 7 mph SW 0%
Monday Night 44°F Mostly Clear 5 mph WSW 0%
Tuesday 67°F Sunny 6 mph SW 1%
Tuesday Night 45°F Mostly Clear 3 mph W 1%
Wednesday 68°F Sunny 2 to 7 mph SSW 2%
Wednesday Night 46°F Mostly Clear 6 mph SSW 4%
Thursday 69°F Sunny 6 to 9 mph SSW 3%
Thursday Night 46°F Mostly Clear 7 mph SSW 5%
Friday 68°F Mostly Sunny 6 to 9 mph SSW 7%
Friday Night 42°F Slight Chance Light Rain then Partly Cloudy 8 mph W 17%

Forecast source: National Weather Service (api.weather.gov) for Basin (46.283, -112.287). Updated through the day.

Growing snapshot for Basin

Last spring frost
Jun 7
First fall frost
Sep 8
Growing season
90 days
Hardiness zone
5a

More local growing data for Basin: nearby ZIP 59631 weather · frost dates · planting calendar · Montana frost dates

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Climate data from the nearest NOAA station, Boulder, Mt (13.8 mi from Basin). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.