Sweet Grass, MT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Sweet Grass, a community in Toole County, Montana.
This Afternoon
47°F
Mostly Sunny
Mostly sunny. High near 47, with temperatures falling to around 41 in the afternoon. South wind 8 to 13 mph, with gusts as high as 20 mph.
7-day forecast for Sweet Grass
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 47°F | Mostly Sunny | 8 to 13 mph S | 0% |
| Tonight | 30°F | Mostly Cloudy | 8 mph WSW | 0% |
| Wednesday | 46°F | Patchy Fog then Mostly Sunny | 6 mph NNW | 0% |
| Wednesday Night | 30°F | Mostly Clear | 3 to 12 mph S | 0% |
| Thursday | 52°F | Mostly Sunny | 12 to 20 mph SW | 0% |
| Thursday Night | 33°F | Partly Cloudy | 12 to 15 mph WSW | 0% |
| Friday | 51°F | Mostly Sunny | 12 to 23 mph SW | 5% |
| Friday Night | 35°F | Partly Cloudy | 15 to 24 mph WSW | 5% |
| Saturday | 51°F | Mostly Sunny | 9 to 15 mph WSW | 1% |
| Saturday Night | 36°F | Mostly Cloudy | 9 to 15 mph SW | 0% |
| Sunday | 57°F | Partly Sunny | 15 to 22 mph SW | 1% |
| Sunday Night | 36°F | Mostly Cloudy | 9 to 18 mph WSW | 2% |
| Monday | 50°F | Partly Sunny | 9 to 13 mph SW | 2% |
| Monday Night | 36°F | Mostly Cloudy | 13 mph SSW | 2% |
Forecast source: National Weather Service (api.weather.gov) for Sweet Grass (48.993, -111.967). Updated through the day.
Growing snapshot for Sweet Grass
Last spring frost
May 17
First fall frost
Sep 25
Growing season
129 days
Hardiness zone
4a
More local growing data for Sweet Grass: nearby ZIP 59482 weather · frost dates · planting calendar · Montana frost dates
Nearby towns & communities
Camrose Colony
Cut Bank
Eagle Creek Colony
Glacier Colony
Hillside Colony
Horizon Colony
Kevin
Rimrock Colony
Santa Rita
Shelby
Sunburst
Climate data from the nearest NOAA station, Sunburst 8 E, Mt (5.9 mi from Sweet Grass). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.