Ontario Weather Forecast

    • 67
    • 78

    Isolated Thunderstorms

    • 74
    • 89

    Isolated Thunderstorms

    • 76
    • 91

    Mostly Sunny

    • 75
    • 92

    Mostly Sunny

    • 75
    • 93

    Mostly Sunny

    • 74
    • 92

    Slight Chance Thunderstorms

Today 27 Jun Knox

Mostly cloudy. A slight chance of Showers early this morning. Highs in the upper 70s. East Winds 5 to 10 Mph. Chance of rain 20 percent.

Tonight 27 Jun Knox

Mostly cloudy. Isolated Showers and Thunderstorms after midnight. Patchy fog after midnight. Lows in the upper 60s. East Winds 5 to 10 Mph. Chance of rain 20 percent.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Ontario Temperature Statistics

June Temperature

Galesburg Municipal Airport (11.8 miles)

  • Lowest 2 June, 2026

    46.4 °F

  • Average June

    69.4 °F

  • Highest 6 June, 2026

    90.3 °F

Climate (2021–2026)

Galesburg Municipal Airport (11.8 miles)

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  • Average Low 2021–2026

    41.7 °F

  • Average 2021–2026

    52 °F

  • Average High 2021–2026

    62.4 °F
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