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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| 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.