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Thief River Falls, MN Weather & Growing Conditions

Tonight
51°F
Partly Cloudy
Partly cloudy. Low around 51, with temperatures rising to around 53 overnight. Southeast wind 3 to 8 mph.

7-day forecast

WhenTempForecastWindPrecip
Tonight 51°F Partly Cloudy 3 to 8 mph SE 3%
Saturday 69°F Mostly Cloudy 3 to 12 mph ENE 11%
Saturday Night 48°F Mostly Cloudy 8 to 13 mph NE 0%
Sunday 65°F Mostly Cloudy 12 mph ENE 0%
Sunday Night 43°F Mostly Cloudy 6 to 9 mph E 0%
Monday 67°F Sunny 6 to 9 mph ESE 0%
Monday Night 41°F Mostly Clear 8 mph SE 0%
Tuesday 67°F Sunny 8 to 13 mph SSE 0%
Tuesday Night 45°F Mostly Clear 12 mph SSE 1%
Wednesday 68°F Mostly Sunny 12 to 16 mph SSE 6%
Wednesday Night 50°F Partly Cloudy then Slight Chance Rain Showers 13 mph SSE 15%
Thursday 71°F Slight Chance Rain Showers then Partly Sunny 13 mph S 15%
Thursday Night 52°F Mostly Clear 9 mph SSE 8%
Friday 72°F Mostly Sunny 8 to 14 mph S 8%

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

Growing snapshot for Thief River Falls, MN

Last spring frost
May 14
First fall frost
Sep 28
Growing season
135 days
Hardiness zone
4a

Explore more for Thief River Falls, MN: full frost dates · planting calendar · Minnesota frost dates

Climate data from the nearest NOAA station, Thief Rvr Falls 2, Mn (1.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.