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.

Fair

58°F

14°C

Humidity 87%
Wind Speed N 7 mph
Barometer 29.95 in (1013.7 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Last update 27 Feb 4:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 85. North wind 5 to 10 mph becoming east in the morning.

    High: 85 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 57. East wind around 5 mph becoming calm in the evening.

    Low: 57 °F

    Mostly Clear

  • Saturday

    Saturday: Patchy fog between 7am and 8am. Otherwise, sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 60. South wind 5 to 10 mph.

    Low: 60 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 60. South wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 60 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 59. Southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 59 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 84. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Cloudy

Detailed Forecast

Today
Sunny, with a high near 85. North wind 5 to 10 mph becoming east in the morning.
Tonight
Mostly clear, with a low around 57. East wind around 5 mph becoming calm in the evening.
Saturday
Patchy fog between 7am and 8am. Otherwise, sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Increasing clouds, with a low around 60. South wind 5 to 10 mph.
Sunday
Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Partly cloudy, with a low around 60. South wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 59. Southeast wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly cloudy, with a high near 84. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 30 percent chance of showers after midnight. Mostly cloudy, with a low around 64.
Wednesday
A 40 percent chance of showers. Mostly cloudy, with a high near 83.
Wednesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 65.
Thursday
A 30 percent chance of showers. Partly sunny, with a high near 84.
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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:
5:12 am CST Feb 27, 2026
Forecast Valid:
5am CST Feb 27, 2026-6pm CST Mar 5, 2026
 
Forecast Discussion
 
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Additional Resources

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