Altadena, CA Weather & Growing Conditions
Tonight
60°F
Mostly Clear
Mostly clear, with a low around 60. East southeast wind around 5 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 60°F | Mostly Clear | 5 mph ESE | 0% |
| Saturday | 83°F | Sunny | 5 mph S | 0% |
| Saturday Night | 62°F | Patchy Fog | 0 to 5 mph SE | 0% |
| Sunday | 81°F | Patchy Fog then Partly Sunny | 0 to 5 mph S | 0% |
| Sunday Night | 61°F | Partly Cloudy | 5 mph SSE | 1% |
| Monday | 77°F | Mostly Sunny | 5 mph S | 1% |
| Monday Night | 59°F | Mostly Clear | 0 to 5 mph SSE | 2% |
| Tuesday | 82°F | Sunny | 0 to 5 mph S | 0% |
| Tuesday Night | 63°F | Clear | 0 to 5 mph SSE | 0% |
| Wednesday | 90°F | Sunny | 0 to 5 mph SW | 1% |
| Wednesday Night | 67°F | Mostly Clear | 0 to 5 mph S | 4% |
| Thursday | 91°F | Sunny | 0 to 5 mph SSE | 4% |
| Thursday Night | 67°F | Mostly Clear | 0 to 5 mph SSE | 0% |
| Friday | 90°F | Sunny | 0 to 5 mph S | 2% |
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.