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Altadena, CA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Altadena, a community in Los Angeles County, California.

Overnight
64°F
Mostly Clear
Mostly clear, with a low around 64. South wind around 0 mph.

7-day forecast for Altadena

WhenTempForecastWindPrecip
Overnight 64°F Mostly Clear 0 mph 0%
Tuesday 93°F Sunny 0 to 5 mph SSW 0%
Tuesday Night 63°F Mostly Clear 0 to 5 mph SSW 0%
Wednesday 92°F Sunny 0 to 5 mph SSW 0%
Wednesday Night 63°F Mostly Clear 0 to 5 mph S 0%
Thursday 93°F Sunny 0 to 5 mph SSW 0%
Thursday Night 65°F Mostly Clear 0 to 5 mph SSW 0%
Friday 94°F Sunny 0 to 5 mph SSW 0%
Friday Night 66°F Mostly Clear 0 to 5 mph S 0%
Saturday 95°F Sunny 0 to 5 mph S 0%
Saturday Night 66°F Mostly Clear 0 to 5 mph S 0%
Sunday 94°F Sunny 0 to 5 mph S 0%
Sunday Night 65°F Mostly Clear 0 to 5 mph S 1%
Monday 90°F Sunny 0 to 5 mph S 1%

Forecast source: National Weather Service (api.weather.gov) for Altadena (34.192, -118.136). Updated through the day.

Growing snapshot for Altadena

Last spring frost
Jan 8
First fall frost
Jan 7
Growing season
365 days
Hardiness zone
10b

More local growing data for Altadena: nearby ZIP 91001 weather · frost dates · planting calendar · California frost dates

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Climate data from the nearest NOAA station, Pasadena, Ca (3.2 mi from Altadena). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.