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Rocky Boy West, MT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Rocky Boy West, a community in Hill County, Montana.

Overnight
29°F
Patchy Fog
Patchy fog. Mostly clear, with a low around 29. Wind around 0 mph.

7-day forecast for Rocky Boy West

WhenTempForecastWindPrecip
Overnight 29°F Patchy Fog 0 mph 0%
Wednesday 43°F Patchy Fog then Sunny 2 mph WNW 0%
Wednesday Night 29°F Partly Cloudy 1 to 5 mph SSE 0%
Thursday 50°F Mostly Sunny 5 to 9 mph SSW 0%
Thursday Night 33°F Partly Cloudy 8 mph SW 2%
Friday 52°F Mostly Sunny 8 to 13 mph SSW 1%
Friday Night 37°F Partly Cloudy 8 to 13 mph SW 1%
Saturday 56°F Mostly Sunny 3 to 8 mph SSW 0%
Saturday Night 39°F Partly Cloudy 3 to 7 mph S 0%
Sunday 61°F Partly Sunny 7 to 14 mph SW 1%
Sunday Night 37°F Partly Cloudy 5 to 14 mph W 1%
Monday 53°F Mostly Sunny 5 mph SW 0%
Monday Night 36°F Mostly Cloudy 3 to 7 mph S 1%
Tuesday 58°F Mostly Sunny 7 to 10 mph SW 0%

Forecast source: National Weather Service (api.weather.gov) for Rocky Boy West (48.297, -109.992). Updated through the day.

Growing snapshot for Rocky Boy West

Last spring frost
May 17
First fall frost
Sep 25
Growing season
128 days
Hardiness zone
4a

More local growing data for Rocky Boy West: nearby ZIP 59521 weather · frost dates · planting calendar · Montana frost dates

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Climate data from the nearest NOAA station, Big Sandy, Mt (12.8 mi from Rocky Boy West). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.