Fallon, MT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Fallon, a community in Prairie County, Montana.
Today
66°F
Rain Showers
Rain showers and patchy fog. Cloudy, with a high near 66. East northeast wind around 13 mph, with gusts as high as 23 mph. Chance of precipitation is 90%.
7-day forecast for Fallon
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 66°F | Rain Showers | 13 mph ENE | 85% |
| Tonight | 51°F | Rain Showers | 13 mph ENE | 93% |
| Sunday | 62°F | Rain Showers | 13 mph E | 87% |
| Sunday Night | 48°F | Slight Chance Rain Showers then Mostly Cloudy | 5 to 10 mph ESE | 20% |
| Monday | 70°F | Partly Sunny | 5 to 13 mph SE | 5% |
| Monday Night | 49°F | Mostly Clear | 7 to 13 mph SE | 0% |
| Tuesday | 79°F | Sunny | 6 to 10 mph SSE | 0% |
| Tuesday Night | 52°F | Mostly Clear | 2 to 10 mph SE | 1% |
| Wednesday | 81°F | Mostly Sunny then Slight Chance Rain Showers | 2 to 6 mph SSE | 15% |
| Wednesday Night | 52°F | Mostly Clear | 5 mph SE | 13% |
| Thursday | 83°F | Mostly Sunny | 2 to 6 mph SE | 2% |
| Thursday Night | 54°F | Mostly Clear | 6 mph SE | 4% |
| Friday | 83°F | Mostly Sunny | 5 to 12 mph SE | 1% |
| Friday Night | 53°F | Partly Cloudy | 8 to 12 mph SSE | 5% |
Forecast source: National Weather Service (api.weather.gov) for Fallon (46.837, -105.127). Updated through the day.
Growing snapshot for Fallon
Last spring frost
May 20
First fall frost
Sep 22
Growing season
124 days
Hardiness zone
4a
More local growing data for Fallon: nearby ZIP 59326 weather · frost dates · planting calendar · Montana frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Mildred 5 N, Mt (4.9 mi from Fallon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.