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

64°F

18°C

Humidity 21%
Wind Speed N 15 G 20 mph
Barometer 30.42 in (1029.7 mb)
Dewpoint 23°F (-5°C)
Visibility 10.00 mi
Last update 12 Mar 12:56 pm CDT
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 67. North northeast wind 5 to 10 mph.

    High: 67 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 41. Calm wind.

    Low: 41 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 78. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 78 °F

    Sunny

  • Friday Night

    Friday Night: Clear, with a low around 49. South wind around 5 mph.

    Low: 49 °F

    Clear

  • Saturday

    Saturday: Sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 84 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 62. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 62 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 92. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 92 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 40. Breezy, with a north wind 20 to 25 mph, with gusts as high as 35 mph.

    Low: 40 °F

    Mostly Clear
    and Breezy

  • Monday

    Monday: Mostly sunny, with a high near 59. North wind 15 to 20 mph, with gusts as high as 35 mph.

    High: 59 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 67. North northeast wind 5 to 10 mph.
Tonight
Clear, with a low around 41. Calm wind.
Friday
Sunny, with a high near 78. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Clear, with a low around 49. South wind around 5 mph.
Saturday
Sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 20 mph.
Saturday Night
Partly cloudy, with a low around 62. South southeast wind around 10 mph, with gusts as high as 20 mph.
Sunday
Partly sunny, with a high near 92. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 40. Breezy, with a north wind 20 to 25 mph, with gusts as high as 35 mph.
Monday
Mostly sunny, with a high near 59. North wind 15 to 20 mph, with gusts as high as 35 mph.
Monday Night
Partly cloudy, with a low around 35.
Tuesday
Mostly sunny, with a high near 69.
Tuesday Night
Partly cloudy, with a low around 45.
Wednesday
Mostly sunny, with a high near 78.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.91°W (Elev. 597 ft)
Last Update:
1:12 pm CDT Mar 12, 2026
Forecast Valid:
1pm CDT Mar 12, 2026-6pm CDT Mar 18, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation