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Altadena, CA Weather & Growing Conditions

Overnight
60°F
Mostly Clear
Mostly clear, with a low around 60. East northeast wind around 5 mph.

7-day forecast

WhenTempForecastWindPrecip
Overnight 60°F Mostly Clear 5 mph ENE 0%
Saturday 84°F Sunny 5 mph S 0%
Saturday Night 63°F Patchy Fog 0 to 5 mph SE 0%
Sunday 82°F Patchy Fog then Mostly Sunny 0 to 5 mph S 0%
Sunday Night 61°F Patchy Fog 5 mph SSE 1%
Monday 78°F Patchy Fog then Mostly Sunny 5 mph SSW 1%
Monday Night 59°F Partly Cloudy 0 to 5 mph S 0%
Tuesday 81°F Sunny 0 to 5 mph S 0%
Tuesday Night 62°F Mostly Clear 0 to 5 mph SE 0%
Wednesday 88°F Sunny 0 to 5 mph SW 0%
Wednesday Night 64°F Mostly Clear 0 to 5 mph SE 0%
Thursday 89°F Sunny 0 to 5 mph S 2%
Thursday Night 65°F Mostly Clear 0 to 5 mph SSE 2%
Friday 88°F Sunny 0 to 5 mph S 3%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Altadena, CA

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

Explore more for Altadena, CA: full frost dates · planting calendar · California frost dates

Climate data from the nearest NOAA station, Pasadena, Ca (3.2 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.