Simi Valley Weather Forecast

    • 58
    • 81

    Increasing Clouds

    • 57
    • 79

    Mostly Cloudy

    • 56
    • 80

    Mostly Sunny

    • 59
    • 82

    Sunny

    • 60
    • 85

    Mostly Sunny

    • 58
    • 83

    Mostly Sunny

    • 58
    • 81

    Mostly Sunny

Today 15 Sep Southeastern Ventura County Valleys

Mostly cloudy in the morning then sunny. Highs in the mid 70s to lower 80s.

Tonight 15 Sep Southeastern Ventura County Valleys

Partly cloudy in the evening then low Clouds and fog with drizzle. Lows in the mid to upper 50s.

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  • Temperature Real-Time

Simi Valley Temperature Statistics

September Temperature

Van Nuys, Van Nuys Airport (14.9 miles)

  • Lowest 2 September, 2026

    60.7 °F

  • Average September

    78.4 °F

  • Highest 9 September, 2026

    107.7 °F

Climate (2021–2026)

Van Nuys, Van Nuys Airport (14.9 miles)

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  • Average Low 2021–2026

    56.6 °F

  • Average 2021–2026

    67.7 °F

  • Average High 2021–2026

    79.5 °F
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