San Marcos Weather Forecast

    • 77
    • 90

    Slight Chance Thunderstorms

    • 78
    • 91

    Mostly Cloudy

    • 73
    • 91

    Rain Showers

    • 72
    • 85

    Rain Showers

    • 69
    • 82

    Rain Showers Likely

    • 69
    • 81

    Rain Showers Likely

Today 17 May Hays

Cloudy. Highs in the upper 80s. South Winds 15 to 20 Mph with Gusts up to 30 Mph.

Tonight 17 May Hays

Cloudy. Lows in the upper 70s. Southeast Winds 10 to 15 Mph with Gusts up to 30 Mph.

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  • Temperature Forecast NOAA

  • Temperature Real-Time

San Marcos Temperature Statistics

May Temperature

San Marcos, San Marcos Municipal Airport (4.3 miles)

  • Lowest 2 May, 2026

    50 °F

  • Average May

    71.4 °F

  • Highest 13 May, 2026

    90 °F

Climate (2021–Present)

San Marcos, San Marcos Municipal Airport (4.3 miles)

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  • Average Low 2021–2026

    60 °F

  • Average 2021–2026

    70.7 °F

  • Average High 2021–2026

    82.3 °F
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