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East Helena, MT Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for East Helena, a city in Lewis And Clark County, Montana.

Today
49°F
Sunny
Sunny. High near 49, with temperatures falling to around 43 in the afternoon. West wind around 1 mph.

7-day forecast for East Helena

WhenTempForecastWindPrecip
Today 49°F Sunny 1 mph W 0%
Tonight 25°F Mostly Clear 1 to 5 mph SSW 0%
Thursday 48°F Partly Sunny 1 to 5 mph SW 2%
Thursday Night 27°F Partly Cloudy 3 to 7 mph SW 2%
Friday 51°F Sunny 3 to 8 mph SSW 0%
Friday Night 33°F Partly Cloudy 5 to 13 mph S 0%
Saturday 56°F Mostly Sunny 3 to 7 mph SE 0%
Saturday Night 33°F Partly Cloudy 5 to 8 mph SSE 0%
Sunday 61°F Mostly Sunny 5 to 8 mph S 3%
Sunday Night 32°F Partly Cloudy 1 to 7 mph WSW 3%
Monday 54°F Mostly Sunny 0 to 3 mph SSE 1%
Monday Night 32°F Mostly Cloudy 3 mph S 1%
Tuesday 58°F Mostly Sunny 2 to 6 mph SSW 2%
Tuesday Night 34°F Partly Cloudy 3 to 7 mph SSW 4%

Forecast source: National Weather Service (api.weather.gov) for East Helena (46.584, -111.921). Updated through the day.

Growing snapshot for East Helena

Last spring frost
May 9
First fall frost
Sep 30
Growing season
142 days
Hardiness zone
5a

More local growing data for East Helena: nearby ZIP 59635 weather · frost dates · planting calendar · Montana frost dates

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Climate data from the nearest NOAA station, Helena Rgnl Ap, Mt (7.9 mi from East Helena). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.