Harlowton, MT Weather & Growing Conditions
Overnight
39°F
Mostly Clear
Mostly clear. Low around 39, with temperatures rising to around 41 overnight. West northwest wind around 5 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 39°F | Mostly Clear | 5 mph WNW | 0% |
| Tuesday | 74°F | Sunny | 3 to 7 mph SSE | 0% |
| Tuesday Night | 44°F | Mostly Clear | 3 to 8 mph N | 3% |
| Wednesday | 84°F | Sunny | 8 to 15 mph W | 0% |
| Wednesday Night | 49°F | Mostly Clear | 6 to 14 mph NW | 0% |
| Thursday | 91°F | Sunny | 8 to 18 mph WNW | 0% |
| Thursday Night | 53°F | Mostly Clear | 6 to 17 mph WNW | 0% |
| Friday | 94°F | Sunny | 6 to 21 mph W | 0% |
| Friday Night | 56°F | Mostly Clear | 13 to 22 mph WNW | 0% |
| Saturday | 93°F | Sunny | 15 to 21 mph WNW | 0% |
| Saturday Night | 55°F | Mostly Clear | 7 to 16 mph NW | 3% |
| Sunday | 90°F | Sunny | 10 to 15 mph NW | 2% |
| Sunday Night | 55°F | Partly Cloudy | 7 to 16 mph N | 5% |
| Monday | 87°F | Sunny | 7 to 15 mph NNE | 6% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Harlowton, MT
Last spring frost
May 23
First fall frost
Sep 16
Growing season
113 days
Hardiness zone
4b
Explore more for Harlowton, MT: full frost dates · planting calendar · Montana frost dates
Climate data from the nearest NOAA station, Harlowton, Mt (2.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.