Mammoth, MT Weather & Growing Conditions
This Afternoon
39°F
Mostly Sunny
Mostly sunny. High near 39, with temperatures falling to around 34 in the afternoon. South southeast wind around 3 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 39°F | Mostly Sunny | 3 mph SSE | 0% |
| Tonight | 28°F | Mostly Cloudy | 2 to 6 mph SSW | 0% |
| Wednesday | 39°F | Mostly Sunny | 2 mph SSE | 0% |
| Wednesday Night | 27°F | Mostly Clear | 2 to 10 mph SSW | 0% |
| Thursday | 38°F | Mostly Sunny | 6 to 10 mph SW | 12% |
| Thursday Night | 26°F | Partly Cloudy | 6 to 13 mph SW | 12% |
| Friday | 38°F | Mostly Sunny | 9 to 13 mph SW | 6% |
| Friday Night | 29°F | Partly Cloudy | 9 to 26 mph SW | 6% |
| Saturday | 40°F | Mostly Sunny | 7 to 21 mph SW | 0% |
| Saturday Night | 32°F | Partly Cloudy | 7 to 21 mph SW | 0% |
| Sunday | 46°F | Mostly Sunny | 8 to 21 mph SSW | 1% |
| Sunday Night | 34°F | Mostly Cloudy | 8 to 15 mph SSW | 1% |
| Monday | 43°F | Partly Sunny | 5 to 10 mph SW | 2% |
| Monday Night | 35°F | Mostly Cloudy | 5 to 16 mph SW | 2% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Mammoth, MT
Last spring frost
Jun 8
First fall frost
Sep 2
Growing season
82 days
Hardiness zone
5a
Explore more for Mammoth, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Twin Bridges, Mt (20.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.