National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

66°F

19°C

Humidity 84%
Wind Speed Calm
Barometer 30.11 in (1019.1 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 23 Mar 8:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Partly sunny, then gradually becoming sunny, with a high near 86. Calm wind becoming south southeast around 5 mph in the afternoon.

    High: 86 °F

    Becoming
    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 60. East wind around 5 mph becoming south southwest after midnight.

    Low: 60 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly cloudy, then gradually becoming sunny, with a high near 87. South wind 5 to 10 mph.

    High: 87 °F

    Decreasing
    Clouds

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 64. South wind 5 to 10 mph.

    Low: 64 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Mostly sunny, with a high near 89. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 89 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 64. South southeast wind around 10 mph.

    Low: 64 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 90 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 89. South wind around 10 mph becoming east southeast in the afternoon.

    High: 89 °F

    Mostly Sunny

Detailed Forecast

Today
Partly sunny, then gradually becoming sunny, with a high near 86. Calm wind becoming south southeast around 5 mph in the afternoon.
Tonight
Mostly clear, with a low around 60. East wind around 5 mph becoming south southwest after midnight.
Tuesday
Mostly cloudy, then gradually becoming sunny, with a high near 87. South wind 5 to 10 mph.
Tuesday Night
Increasing clouds, with a low around 64. South wind 5 to 10 mph.
Wednesday
Mostly sunny, with a high near 89. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Mostly clear, with a low around 64. South southeast wind around 10 mph.
Thursday
Mostly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday Night
Mostly clear, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Friday
Mostly sunny, with a high near 89. South wind around 10 mph becoming east southeast in the afternoon.
Friday Night
Mostly clear, with a low around 57.
Saturday
Mostly sunny, with a high near 76.
Saturday Night
Partly cloudy, with a low around 54.
Sunday
Mostly sunny, with a high near 82.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
9:32 am CDT Mar 23, 2026
Forecast Valid:
9am CDT Mar 23, 2026-6pm CDT Mar 29, 2026
 
Forecast Discussion
 
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Additional Resources

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