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
74°F
Mostly Sunny
Mostly sunny, with a high near 74. North northeast wind around 9 mph.
7-day forecast for Great Falls
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 74°F | Mostly Sunny | 9 mph NNE | 7% |
| Tonight | 52°F | Chance Rain | 1 to 9 mph N | 37% |
| Saturday | 66°F | Chance Light Rain | 2 to 7 mph NE | 26% |
| Saturday Night | 48°F | Mostly Cloudy then Patchy Fog | 1 to 7 mph SSE | 8% |
| Sunday | 75°F | Patchy Fog then Mostly Sunny | 2 mph S | 2% |
| Sunday Night | 49°F | Mostly Clear | 2 to 6 mph SE | 0% |
| Monday | 81°F | Sunny | 5 mph SSW | 0% |
| Monday Night | 51°F | Mostly Clear | 2 to 6 mph SSW | 0% |
| Tuesday | 79°F | Sunny | 5 mph WSW | 0% |
| Tuesday Night | 51°F | Mostly Clear | 5 mph SSE | 1% |
| Wednesday | 80°F | Sunny | 3 to 7 mph SW | 1% |
| Wednesday Night | 52°F | Mostly Clear | 5 mph SSW | 3% |
| Thursday | 81°F | Sunny | 6 mph SSW | 2% |
| Thursday Night | 53°F | Partly Cloudy | 6 mph S | 1% |
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
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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 Sep 19, 2026.