Lake Riverside Weather Forecast

    • 55
    • 84

    Sunny

    • 60
    • 90

    Sunny

    • 60
    • 91

    Sunny

    • 61
    • 89

    Sunny

    • 61
    • 88

    Sunny

    • 59
    • 87

    Sunny

Today 30 Sep Riverside County Mountains

Sunny, warmer. Highs 76 to 86. Areas of Winds north 10 Mph becoming west this afternoon. Gusts to 25 Mph.

Tonight 30 Sep Riverside County Mountains

Clear. Lows 48 to 58. Areas of Winds north 10 to 15 Mph.

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  • Temperature Real-Time

Lake Riverside Temperature Statistics

September Temperature

Big Bear City Airport (51.6 miles)

  • Lowest 19 September, 2026

    32.7 °F
  • Average September

    59.2 °F
  • Highest 10 September, 2026

    81.3 °F

Climate (2021–2026)

Big Bear City Airport (51.6 miles)

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  • Average Low 2021–2026

    33.8 °F
  • Average 2021–2026

    48.8 °F
  • Average High 2021–2026

    60.4 °F
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