Thief River Falls, MN Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Thief River Falls, a city in Pennington County, Minnesota.
Today
71°F
Sunny
Sunny. High near 71, with temperatures falling to around 69 in the afternoon. West northwest wind 10 to 15 mph.
7-day forecast for Thief River Falls
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 71°F | Sunny | 10 to 15 mph WNW | 0% |
| Tonight | 49°F | Mostly Clear | 3 to 13 mph SW | 0% |
| Wednesday | 78°F | Sunny | 6 to 15 mph SW | 0% |
| Wednesday Night | 57°F | Slight Chance Rain Showers | 9 to 13 mph SW | 19% |
| Thursday | 81°F | Sunny | 8 to 14 mph WSW | 5% |
| Thursday Night | 57°F | Mostly Clear | 6 to 12 mph WSW | 4% |
| Friday | 79°F | Sunny | 6 to 13 mph W | 4% |
| Friday Night | 54°F | Mostly Clear | 3 to 13 mph NNE | 9% |
| Saturday | 77°F | Mostly Sunny | 3 to 12 mph NNE | 9% |
| Saturday Night | 55°F | Slight Chance Rain Showers | 5 to 12 mph NNE | 15% |
| Sunday | 76°F | Mostly Sunny | 6 to 10 mph N | 12% |
| Sunday Night | 56°F | Partly Cloudy then Slight Chance Rain Showers | 6 to 10 mph NNE | 22% |
| Monday | 76°F | Slight Chance Rain Showers then Mostly Sunny | 5 to 10 mph NNE | 22% |
| Monday Night | 56°F | Slight Chance Rain Showers | 5 to 10 mph NNE | 15% |
Forecast source: National Weather Service (api.weather.gov) for Thief River Falls (48.111, -96.178). Updated through the day.
Growing snapshot for Thief River Falls
Last spring frost
May 14
First fall frost
Sep 28
Growing season
135 days
Hardiness zone
4a
More local growing data for Thief River Falls: nearby ZIP 56701 weather · frost dates · planting calendar · Minnesota frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Thief Rvr Falls 2, Mn (1.2 mi from Thief River Falls). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.