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.

Overcast

71°F

22°C

Humidity 73%
Wind Speed S 15 G 18 mph
Barometer 30.11 in (1019.2 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Last update 2 Mar 9:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly cloudy, then gradually becoming sunny, with a high near 82. South wind around 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Decreasing
    Clouds

  • Tonight

    Tonight: Increasing clouds, with a low around 63. South southeast wind around 10 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Mostly cloudy, then gradually becoming sunny, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 86 °F

    Decreasing
    Clouds

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Increasing clouds, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 66 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers before 9am, then a chance of showers and thunderstorms between 9am and noon, then showers likely and possibly a thunderstorm after noon. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.

    High: 86 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 40%.

    Low: 66 °F

    Chance
    T-storms then
    Chance
    Showers

  • Thursday

    Thursday: Partly sunny, with a high near 87. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 87 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 67 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Friday

    Friday: 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 30 mph. Chance of precipitation is 50%.

    High: 85 °F

    Chance
    Showers

Detailed Forecast

Today
Mostly cloudy, then gradually becoming sunny, with a high near 82. South wind around 10 mph, with gusts as high as 20 mph.
Tonight
Increasing clouds, with a low around 63. South southeast wind around 10 mph.
Tuesday
Mostly cloudy, then gradually becoming sunny, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Increasing clouds, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A chance of showers before 9am, then a chance of showers and thunderstorms between 9am and noon, then showers likely and possibly a thunderstorm after noon. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 40%.
Thursday
Partly sunny, with a high near 87. South wind 10 to 15 mph, with gusts as high as 30 mph.
Thursday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
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 30 mph. Chance of precipitation is 50%.
Friday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 65. Chance of precipitation is 70%.
Saturday
Showers and possibly a thunderstorm. High near 80. Chance of precipitation is 80%.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 60. Chance of precipitation is 70%.
Sunday
Showers likely. Mostly cloudy, with a high near 73. Chance of precipitation is 70%.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
10:32 am CST Mar 2, 2026
Forecast Valid:
10am CST Mar 2, 2026-6pm CDT Mar 8, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation