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Thompson Falls, MT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Thompson Falls, a city in Sanders County, Montana.

This Afternoon
52°F
Partly Sunny
Partly sunny. High near 52, with temperatures falling to around 47 in the afternoon. East wind around 1 mph.

7-day forecast for Thompson Falls

WhenTempForecastWindPrecip
This Afternoon 52°F Partly Sunny 1 mph E 1%
Tonight 27°F Mostly Cloudy then Patchy Fog 0 mph 2%
Wednesday 55°F Patchy Fog then Sunny 2 mph SE 0%
Wednesday Night 27°F Partly Cloudy then Areas Of Fog 1 mph SSE 12%
Thursday 48°F Chance Light Rain 0 to 5 mph SW 40%
Thursday Night 30°F Mostly Cloudy 3 mph SSW 11%
Friday 51°F Slight Chance Light Rain 2 to 6 mph SSW 24%
Friday Night 33°F Slight Chance Light Rain then Mostly Cloudy 1 to 9 mph SSW 24%
Saturday 56°F Partly Sunny 2 mph S 4%
Saturday Night 33°F Mostly Cloudy then Slight Chance Light Rain 3 mph SSE 19%
Sunday 59°F Chance Light Rain 2 to 6 mph SSW 43%
Sunday Night 33°F Slight Chance Light Rain 0 to 3 mph SW 23%
Monday 55°F Slight Chance Light Rain 2 mph S 23%
Monday Night 33°F Chance Light Rain 2 mph S 30%

Forecast source: National Weather Service (api.weather.gov) for Thompson Falls (47.599, -115.343). Updated through the day.

Growing snapshot for Thompson Falls

Last spring frost
May 7
First fall frost
Oct 4
Growing season
150 days
Hardiness zone
6a

More local growing data for Thompson Falls: nearby ZIP 59873 weather · frost dates · planting calendar · Montana frost dates

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Climate data from the nearest NOAA station, Thompson Falls Ph, Mt (6.3 mi from Thompson Falls). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 3, 2026.