Simi Valley, CA Weather & Growing Conditions
Overnight
66°F
Mostly Clear
Mostly clear, with a low around 66. East northeast wind around 0 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 66°F | Mostly Clear | 0 mph | 0% |
| Tuesday | 89°F | Sunny | 0 to 10 mph S | 0% |
| Tuesday Night | 65°F | Mostly Clear | 0 to 10 mph SE | 0% |
| Wednesday | 88°F | Sunny | 0 to 10 mph SSW | 0% |
| Wednesday Night | 66°F | Clear | 0 to 10 mph SW | 0% |
| Thursday | 88°F | Sunny | 0 to 10 mph SSE | 0% |
| Thursday Night | 64°F | Clear | 0 to 10 mph SW | 0% |
| Friday | 91°F | Sunny | 0 to 10 mph S | 0% |
| Friday Night | 65°F | Mostly Clear | 0 to 10 mph SW | 0% |
| Saturday | 92°F | Sunny | 0 to 10 mph S | 0% |
| Saturday Night | 65°F | Clear | 0 to 10 mph SSE | 0% |
| Sunday | 91°F | Sunny | 0 to 10 mph S | 0% |
| Sunday Night | 64°F | Mostly Clear | 0 to 10 mph SSE | 0% |
| Monday | 88°F | Sunny | 0 to 10 mph S | 1% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Simi Valley, CA
Last spring frost
Jan 8
First fall frost
Jan 1
Growing season
365 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, Newhall 5Nw, Ca (7.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.