Ontario International Airport Weather Forecast

    • 70
    • 98

    Hot

    • 69
    • 91

    Rain Showers Likely

    • 67
    • 83

    Rain Showers Likely

    • 66
    • 83

    Chance Rain Showers

    • 68
    • 87

    Partly Sunny

    • 69
    • 90

    Partly Sunny

    • 69
    • 90

    Mostly Sunny

Today 16 Sep San Bernardino and Riverside County Valleys-The Inland Empire

Mostly sunny. Highs 95 to 101. Light Winds becoming west 10 to 15 Mph with Gusts to 25 Mph this afternoon.

Tonight 16 Sep San Bernardino and Riverside County Valleys-The Inland Empire

Mostly clear this evening. Becoming partly cloudy. Lows 65 to 70. Areas of Winds west 10 to 15 Mph this evening becoming light.

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  • Temperature Real-Time

Ontario International Airport Temperature Statistics

September Temperature

Ontario International Airport (1.2 miles)

  • Lowest 12 September, 2025

    62.1 °F

  • Average September

    76.9 °F

  • Highest 2 September, 2025

    102 °F

Climate (2020–Present)

Ontario International Airport (1.2 miles)

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  • Average Low 2020–2025

    55.5 °F

  • Average 2020–2025

    66.7 °F

  • Average High 2020–2025

    79.1 °F
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