Sebastian Weather Forecast

    • 73
    • 91

    Chance Thunderstorms

    • 73
    • 92

    Chance Thunderstorms

    • 74
    • 93

    Chance Thunderstorms

    • 75
    • 93

    Chance Thunderstorms

    • 76
    • 95

    Chance Thunderstorms

    • 75
    • 96

    Chance Thunderstorms

Today 18 Sep Inland Willacy

Mostly sunny with a chance of Showers. A slight chance of Thunderstorms this Morning, then a chance of Thunderstorms this afternoon. Highs around 90. East Winds 10 to 15 Mph. Chance of rain 50 percent.

Tonight 18 Sep Inland Willacy

Partly cloudy in the Evening, then clearing. Lows in the lower 70s. East Winds 5 to 10 Mph.

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Sebastian Temperature Statistics

September Temperature

Harlingen, Rio Grande Valley International Airport (11.2 miles)

  • Lowest 16 September, 2025

    70 °F

  • Average September

    82.9 °F

  • Highest 4 September, 2025

    100 °F

Climate (2020–Present)

Harlingen, Rio Grande Valley International Airport (11.2 miles)

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  • Average Low 2020–2025

    65.4 °F

  • Average 2020–2025

    75.2 °F

  • Average High 2020–2025

    86.1 °F
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