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Simi Valley, CA Weather & Growing Conditions

Overnight
63°F
Mostly Clear
Mostly clear, with a low around 63. East northeast wind around 0 mph.

7-day forecast

WhenTempForecastWindPrecip
Overnight 63°F Mostly Clear 0 mph 0%
Tuesday 86°F Sunny 0 to 10 mph SW 0%
Tuesday Night 63°F Mostly Clear 0 to 10 mph SE 0%
Wednesday 85°F Sunny 5 to 10 mph SSW 0%
Wednesday Night 64°F Clear 0 to 10 mph S 0%
Thursday 85°F Sunny 0 to 10 mph S 0%
Thursday Night 63°F Mostly Clear 0 to 10 mph SSE 0%
Friday 90°F Sunny 0 to 10 mph S 0%
Friday Night 64°F Mostly Clear 0 to 10 mph S 0%
Saturday 91°F Sunny 0 to 10 mph S 0%
Saturday Night 64°F Clear 0 to 10 mph SE 0%
Sunday 90°F Sunny 0 to 10 mph S 0%
Sunday Night 63°F Mostly Clear 5 to 10 mph SSE 0%
Monday 87°F Sunny 5 to 10 mph SSE 1%

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

Growing snapshot for Simi Valley, CA

Last spring frost
Jan 24
First fall frost
Dec 15
Growing season
329 days
Hardiness zone
10a

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

Climate data from the nearest NOAA station, Woodland Hills Pierce College, Ca (8.4 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.