Helena Valley Northwest, MT Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Helena Valley Northwest, a community in Lewis And Clark County, Montana.
Overnight
26°F
Partly Cloudy
Partly cloudy, with a low around 26. West northwest wind around 1 mph.
7-day forecast for Helena Valley Northwest
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 26°F | Partly Cloudy | 1 mph WNW | 0% |
| Wednesday | 49°F | Mostly Sunny | 2 mph W | 0% |
| Wednesday Night | 26°F | Mostly Clear | 3 mph NW | 0% |
| Thursday | 49°F | Partly Sunny | 2 to 8 mph SW | 0% |
| Thursday Night | 27°F | Partly Cloudy | 6 to 9 mph SW | 0% |
| Friday | 50°F | Mostly Sunny | 6 to 12 mph SSW | 0% |
| Friday Night | 33°F | Partly Cloudy | 6 to 18 mph SSW | 0% |
| Saturday | 57°F | Mostly Sunny | 3 to 7 mph S | 0% |
| Saturday Night | 33°F | Partly Cloudy | 3 to 8 mph S | 0% |
| Sunday | 61°F | Mostly Sunny | 6 to 10 mph SSW | 3% |
| Sunday Night | 32°F | Partly Cloudy | 2 to 9 mph WSW | 3% |
| Monday | 54°F | Partly Sunny | 3 mph SSW | 1% |
| Monday Night | 32°F | Mostly Cloudy | 3 mph SSW | 0% |
| Tuesday | 57°F | Mostly Sunny | 3 to 7 mph SW | 2% |
Forecast source: National Weather Service (api.weather.gov) for Helena Valley Northwest (46.729, -112.058). Updated through the day.
Growing snapshot for Helena Valley Northwest
Last spring frost
May 9
First fall frost
Sep 30
Growing season
142 days
Hardiness zone
4b
More local growing data for Helena Valley Northwest: nearby ZIP 59636 weather · frost dates · planting calendar · Montana frost dates
Nearby towns & communities
Canyon Creek
Craig
East Helena
Helena
Helena Valley Northeast
Helena Valley Southeast
Helena Valley West Central
Helena West Side
Lincoln
Marysville
Milford Colony
Montana City
Rimini
South Hills
Spokane Creek
Unionville
Wolf Creek
York
Climate data from the nearest NOAA station, Helena Rgnl Ap, Mt (7.2 mi from Helena Valley Northwest). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.