Costa Mesa Weather Forecast

    • 65
    • 74

    Increasing Clouds

    • 65
    • 77

    Partly Sunny

    • 64
    • 77

    Partly Sunny

    • 67
    • 79

    Patchy Fog

    • 67
    • 81

    Patchy Fog

    • 67
    • 81

    Partly Sunny

Today 13 Sep Orange County Coastal

Cloudy this morning. Becoming mostly sunny. Highs 71 to 74 at the Beaches to 75 to 78 farther inland and near higher coastal Terrain. Areas of Winds south 10 Mph.

Tonight 13 Sep Orange County Coastal

Mostly clear in the evening. Becoming cloudy overnight with patchy fog. Lows 62 to 66. Areas of Winds southwest 10 Mph in the evening becoming light.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

Costa Mesa Temperature Statistics

September Temperature

John Wayne-Orange County Airport (3.7 miles)

  • Lowest 5 September, 2025

    66.9 °F

  • Average September

    73.8 °F

  • Highest 3 September, 2025

    86 °F

Climate (2020–Present)

John Wayne-Orange County Airport (3.7 miles)

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  • Average Low 2020–2025

    58.7 °F

  • Average 2020–2025

    65.7 °F

  • Average High 2020–2025

    73.6 °F
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