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 and Breezy

82°F

28°C

Humidity 46%
Wind Speed SW 21 G 29 mph
Barometer 29.87 in (1011.0 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 17 Feb 1:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 83. South wind around 15 mph, with gusts as high as 25 mph.

    High: 83 °F

    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 60. South wind 5 to 10 mph becoming west southwest after midnight. Winds could gust as high as 20 mph.

    Low: 60 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Mostly cloudy, then gradually becoming sunny, with a high near 82. South wind 5 to 10 mph.

    High: 82 °F

    Decreasing
    Clouds

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 61. South wind around 5 mph.

    Low: 61 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Patchy fog before 7am. Otherwise, mostly sunny, with a high near 84. South wind around 5 mph becoming north in the afternoon.

    High: 84 °F

    Patchy Fog
    then Mostly
    Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 59. East wind around 5 mph becoming south southeast after midnight.

    Low: 59 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 77. North northeast wind around 5 mph.

    High: 77 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 58. Northeast wind around 5 mph becoming northwest after midnight.

    Low: 58 °F

    Mostly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 75. North wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 75 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 83. South wind around 15 mph, with gusts as high as 25 mph.
Tonight
Increasing clouds, with a low around 60. South wind 5 to 10 mph becoming west southwest after midnight. Winds could gust as high as 20 mph.
Wednesday
Mostly cloudy, then gradually becoming sunny, with a high near 82. South wind 5 to 10 mph.
Wednesday Night
Increasing clouds, with a low around 61. South wind around 5 mph.
Thursday
Patchy fog before 7am. Otherwise, mostly sunny, with a high near 84. South wind around 5 mph becoming north in the afternoon.
Thursday Night
Mostly cloudy, with a low around 59. East wind around 5 mph becoming south southeast after midnight.
Friday
Mostly cloudy, with a high near 77. North northeast wind around 5 mph.
Friday Night
Mostly cloudy, with a low around 58. Northeast wind around 5 mph becoming northwest after midnight.
Saturday
Mostly sunny, with a high near 75. North wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Mostly clear, with a low around 42.
Sunday
Sunny, with a high near 65.
Sunday Night
Mostly clear, with a low around 38.
Monday
Sunny, with a high near 65.
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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:
12:44 pm CST Feb 17, 2026
Forecast Valid:
2pm CST Feb 17, 2026-6pm CST Feb 23, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation