Mount Vernon Weather Forecast

    • 74
    • 102

    Chance Thunderstorms

    • 73
    • 102

    Slight Chance Thunderstorms

    • 72
    • 99

    Chance Rain Showers

    • 69
    • 96

    Slight Chance Thunderstorms

    • 66
    • 94

    Slight Chance Thunderstorms

    • 65
    • 93

    Sunny

Today 23 Aug San Bernardino and Riverside County Valleys-The Inland Empire

Partly cloudy with a slight chance of Showers and Thunderstorms. Highs 97 to 102. Light Winds becoming west 10 Mph in the afternoon. Chance of measurable precipitation 20 percent.

Tonight 23 Aug San Bernardino and Riverside County Valleys-The Inland Empire

Partly cloudy with a slight chance of Showers and Thunderstorms in the Evening, then mostly clear overnight. Lows 69 to 74. Areas of Winds west to 10 Mph in the evening becoming light. Chance of measurable precipitation 20 percent.

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  • Temperature Real-Time

Mount Vernon Temperature Statistics

August Temperature

San Bernardino Intl. Airport (4.3 miles)

  • Lowest 18 August, 2025

    60.8 °F

  • Average August

    75.8 °F

  • Highest 7 August, 2025

    105.8 °F

Climate (2020–Present)

San Bernardino Intl. Airport (4.3 miles)

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  • Average Low 2020–2025

    54.1 °F

  • Average 2020–2025

    63.2 °F

  • Average High 2020–2025

    80.5 °F
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