Harman US

Simi Valley, CA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Simi Valley, a city in Ventura County, California.

This Afternoon
82°F
Sunny
Sunny, with a high near 82. West southwest wind 5 to 10 mph.

7-day forecast for Simi Valley

WhenTempForecastWindPrecip
This Afternoon 82°F Sunny 5 to 10 mph WSW 0%
Tonight 56°F Mostly Clear 5 mph NE 0%
Saturday 86°F Sunny 0 to 10 mph WSW 0%
Saturday Night 57°F Mostly Cloudy then Patchy Fog 5 mph E 0%
Sunday 84°F Patchy Fog then Partly Sunny 5 to 10 mph SSW 0%
Sunday Night 56°F Partly Cloudy 0 to 5 mph SSE 1%
Monday 80°F Mostly Sunny 5 to 10 mph S 0%
Monday Night 58°F Mostly Clear 0 to 10 mph W 0%
Tuesday 80°F Sunny 0 to 10 mph S 0%
Tuesday Night 61°F Clear 0 to 10 mph NNE 0%
Wednesday 89°F Sunny 0 to 10 mph SW 0%
Wednesday Night 64°F Mostly Clear 0 to 10 mph N 2%
Thursday 89°F Sunny 0 to 10 mph SSW 1%
Thursday Night 64°F Mostly Clear 0 to 10 mph NNE 1%

Forecast source: National Weather Service (api.weather.gov) for Simi Valley (34.267, -118.748). Updated through the day.

Growing snapshot for Simi Valley

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

More local growing data for Simi Valley: nearby ZIP 93065 weather · frost dates · planting calendar · California frost dates

Nearby towns & communities

All California locations ›

Climate data from the nearest NOAA station, Woodland Hills Pierce College, Ca (12.6 mi from Simi Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.