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

54°F

12°C

Humidity 64%
Wind Speed SW 10 mph
Barometer 30.10 in (1019.1 mb)
Dewpoint 42°F (6°C)
Visibility 10.00 mi
Wind Chill51°F (11°C)
Last update 13 Mar 8:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 80. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 80 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 50. South wind around 5 mph.

    Low: 50 °F

    Clear

  • Saturday

    Saturday: Sunny, with a high near 85. South wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 85 °F

    Sunny

  • Saturday Night

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

    Low: 62 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Partly sunny, with a high near 91. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 40. North wind 15 to 20 mph, with gusts as high as 35 mph.

    Low: 40 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 58. North wind 15 to 20 mph, with gusts as high as 30 mph.

    High: 58 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 35. North northeast wind 5 to 10 mph becoming light and variable in the evening.

    Low: 35 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 69. Light south southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 69 °F

    Sunny

Detailed Forecast

Today
Sunny, with a high near 80. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Tonight
Clear, with a low around 50. South wind around 5 mph.
Saturday
Sunny, with a high near 85. South wind 5 to 15 mph, with gusts as high as 20 mph.
Saturday Night
Increasing clouds, 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 91. South southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 40. North wind 15 to 20 mph, with gusts as high as 35 mph.
Monday
Mostly sunny, with a high near 58. North wind 15 to 20 mph, with gusts as high as 30 mph.
Monday Night
Partly cloudy, with a low around 35. North northeast wind 5 to 10 mph becoming light and variable in the evening.
Tuesday
Sunny, with a high near 69. Light south southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 44.
Wednesday
Mostly sunny, with a high near 78.
Wednesday Night
Mostly clear, with a low around 52.
Thursday
Mostly sunny, with a high near 83.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.9°N 97.91°W (Elev. 640 ft)
Last Update:
6:42 am CDT Mar 13, 2026
Forecast Valid:
9am CDT Mar 13, 2026-6pm CDT Mar 19, 2026
 
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Additional Resources

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