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

85°F

29°C

Humidity 32%
Wind Speed S 12 G 22 mph
Barometer 29.96 in (1013.8 mb)
Dewpoint 52°F (11°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 28 Feb 1:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 86. South wind around 10 mph, with gusts as high as 20 mph.

    High: 86 °F

    Sunny

  • Tonight

    Tonight: Patchy fog after 3am. Otherwise, increasing clouds, with a low around 58. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 58 °F

    Clear then
    Patchy Fog

  • Sunday

    Sunday: Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 83. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 83 °F

    Patchy Fog
    then Sunny

  • Sunday Night

    Sunday Night: Increasing clouds, with a low around 60. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.

    Low: 60 °F

    Increasing
    Clouds

  • Monday

    Monday: Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 84 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 61. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 61 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 88. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 88 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 65 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers, with thunderstorms also possible after noon. Partly sunny, with a high near 85. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.

    High: 85 °F

    Chance
    Showers

Detailed Forecast

This Afternoon
Sunny, with a high near 86. South wind around 10 mph, with gusts as high as 20 mph.
Tonight
Patchy fog after 3am. Otherwise, increasing clouds, with a low around 58. South wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday
Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 83. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Increasing clouds, with a low around 60. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.
Monday
Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 20 mph.
Monday Night
Partly cloudy, with a low around 61. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Tuesday
Partly sunny, with a high near 88. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A chance of showers, with thunderstorms also possible after noon. Partly sunny, with a high near 85. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.
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 86.
Thursday Night
Mostly cloudy, with a low around 65.
Friday
A 30 percent chance of showers. Mostly cloudy, with a high near 86.
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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 28, 2026
Forecast Valid:
2pm CST Feb 28, 2026-6pm CST Mar 6, 2026
 
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Additional Resources

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Chance of Precipitation