Custer, MT Weather & Growing Conditions
Overnight
55°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 3am, then patchy fog and showers and thunderstorms. Cloudy. Low around 55, with temperatures rising to around 57 overnight. North wind around 8 mph. Chance of precipitation is 90%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 55°F | Chance Showers And Thunderstorms | 8 mph N | 87% |
| Saturday | 61°F | Patchy Fog | 9 to 13 mph NNE | 100% |
| Saturday Night | 50°F | Patchy Fog | 7 to 12 mph NNE | 98% |
| Sunday | 61°F | Rain Showers | 8 mph NNE | 84% |
| Sunday Night | 48°F | Slight Chance Rain Showers then Areas Of Fog | 0 to 6 mph E | 24% |
| Monday | 71°F | Areas Of Fog then Partly Sunny | 0 to 6 mph SSE | 0% |
| Monday Night | 48°F | Mostly Clear | 0 to 5 mph SE | 0% |
| Tuesday | 77°F | Sunny | 0 to 6 mph SW | 0% |
| Tuesday Night | 51°F | Partly Cloudy then Slight Chance Rain Showers | 0 to 3 mph SE | 15% |
| Wednesday | 79°F | Mostly Sunny | 0 to 5 mph SW | 4% |
| Wednesday Night | 52°F | Partly Cloudy | 2 mph SE | 4% |
| Thursday | 81°F | Sunny | 1 to 7 mph SSW | 0% |
| Thursday Night | 52°F | Mostly Clear | 1 to 5 mph SE | 2% |
| Friday | 80°F | Mostly Sunny | 1 to 7 mph S | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Custer, MT
Last spring frost
May 22
First fall frost
Sep 22
Growing season
121 days
Hardiness zone
4b
Explore more for Custer, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Pompeys Pillar 15N, Mt (11 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.