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

71°F

22°C

Humidity 96%
Wind Speed SE 9 mph
Barometer 30.09 in (1018.3 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Last update 13 Apr 7:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: A 20 percent chance of showers and thunderstorms after 4pm. Mostly cloudy, with a high near 83. South wind around 10 mph, with gusts as high as 20 mph.

    High: 83 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Tonight

    Tonight: A 10 percent chance of showers and thunderstorms before 7pm. Increasing clouds, with a low around 68. South wind around 10 mph, with gusts as high as 20 mph.

    Low: 68 °F

    Slight Chance
    T-storms then
    Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 83 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 68. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 68 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 82 °F

    Cloudy then
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 67. South southeast wind 5 to 10 mph.

    Low: 67 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: Partly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 87 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 67 °F

    Partly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 88. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 88 °F

    Mostly Cloudy

Detailed Forecast

Today
A 20 percent chance of showers and thunderstorms after 4pm. Mostly cloudy, with a high near 83. South wind around 10 mph, with gusts as high as 20 mph.
Tonight
A 10 percent chance of showers and thunderstorms before 7pm. Increasing clouds, with a low around 68. South wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Mostly cloudy, with a low around 68. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A 30 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 20 mph.
Wednesday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 67. South southeast wind 5 to 10 mph.
Thursday
Partly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Partly cloudy, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.
Friday
Mostly cloudy, with a high near 88. South wind 10 to 15 mph, with gusts as high as 30 mph.
Friday Night
Mostly cloudy, with a low around 70.
Saturday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 85.
Saturday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 56.
Sunday
A 20 percent chance of showers. Mostly cloudy, with a high near 73.
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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:
6:42 am CDT Apr 13, 2026
Forecast Valid:
8am CDT Apr 13, 2026-6pm CDT Apr 19, 2026
 
Forecast Discussion
 
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Additional Resources

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National Digital Forecast Database Weather Element Forecast

Chance of Precipitation