Great Falls, MT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Great Falls, a city in Cascade County, Montana.
This Afternoon
58°F
Mostly Sunny
Mostly sunny. High near 58, with temperatures falling to around 49 in the afternoon. South southeast wind around 2 mph.
7-day forecast for Great Falls
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 58°F | Mostly Sunny | 2 mph SSE | 0% |
| Tonight | 30°F | Mostly Cloudy | 3 mph SW | 0% |
| Wednesday | 50°F | Mostly Sunny | 0 to 3 mph WNW | 0% |
| Wednesday Night | 32°F | Mostly Clear | 0 to 6 mph SSW | 0% |
| Thursday | 56°F | Mostly Sunny | 6 to 16 mph SW | 0% |
| Thursday Night | 36°F | Mostly Clear | 14 mph SW | 0% |
| Friday | 55°F | Mostly Sunny | 12 to 24 mph SW | 1% |
| Friday Night | 38°F | Partly Cloudy | 13 to 22 mph SW | 4% |
| Saturday | 56°F | Mostly Sunny | 6 to 15 mph SW | 0% |
| Saturday Night | 39°F | Partly Cloudy | 6 to 13 mph SSW | 0% |
| Sunday | 62°F | Partly Sunny | 12 to 18 mph SW | 0% |
| Sunday Night | 39°F | Mostly Cloudy | 6 to 12 mph SW | 1% |
| Monday | 56°F | Partly Sunny | 6 mph SW | 2% |
| Monday Night | 39°F | Mostly Cloudy | 3 to 9 mph SSW | 2% |
Forecast source: National Weather Service (api.weather.gov) for Great Falls (47.503, -111.300). Updated through the day.
Growing snapshot for Great Falls
Last spring frost
May 6
First fall frost
Oct 1
Growing season
147 days
Hardiness zone
4b
More local growing data for Great Falls: nearby ZIP 59401 weather · frost dates · planting calendar · Montana frost dates
Nearby towns & communities
Belt
Big Stone Colony
Black Eagle
Cascade
Cascade Colony
Centerville
Fair Haven Colony
Fairfield
Fort Shaw
Gibson Flats
Hardy
Malmstrom AFB
Monarch
Neihart
Pleasant Valley Colony
Riceville
Sand Coulee
Simms
Stockett
Sun Prairie
Sun River
Tracy
Ulm
Vaughn
Climate data from the nearest NOAA station, Great Falls 16St, Mt (1.6 mi from Great Falls). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.