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

70°F

21°C

Humidity 84%
Wind Speed S 17 mph
Barometer 30.04 in (1016.8 mb)
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Last update 3 Mar 8:56 am CST
Extended Forecast for

San Marcos TX

  • Today

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

    High: 86 °F

    Decreasing
    Clouds

  • Tonight

    Tonight: A slight chance of drizzle after 3am. Increasing clouds, with a low around 67. South wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 67 °F

    Partly Cloudy
    then Slight
    Chance
    Drizzle

  • Wednesday

    Wednesday: A chance of showers, then showers likely and possibly a thunderstorm after noon. Mostly cloudy, with a high near 84. South southeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 84 °F

    Showers
    Likely

  • Wednesday Night

    Wednesday Night: A chance of showers and thunderstorms before midnight, then a slight chance of showers. 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
    Showers

  • Thursday

    Thursday: A 30 percent chance of showers and thunderstorms before noon. Partly sunny, with a high near 86. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 86 °F

    Chance
    Showers then
    Mostly 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 slight chance of showers, then a chance of showers and thunderstorms after noon. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 50%.

    High: 86 °F

    Slight Chance
    Showers then
    Chance
    Showers

  • Friday Night

    Friday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 67. South southeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 50%.

    Low: 67 °F

    Chance
    T-storms then
    Chance
    Showers

  • Saturday

    Saturday: A chance of showers, then showers and possibly a thunderstorm after noon. High near 84. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%.

    High: 84 °F

    Chance
    Showers then
    Showers

Detailed Forecast

Today
Mostly cloudy, then gradually becoming sunny, with a high near 86. South wind around 15 mph, with gusts as high as 25 mph.
Tonight
A slight chance of drizzle after 3am. Increasing clouds, with a low around 67. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A chance of showers, then showers likely and possibly a thunderstorm after noon. Mostly cloudy, with a high near 84. South southeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Wednesday Night
A chance of showers and thunderstorms before midnight, then a slight chance of showers. 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
A 30 percent chance of showers and thunderstorms before noon. Partly sunny, with a high near 86. South southeast 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 slight chance of showers, then a chance of showers and thunderstorms after noon. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 50%.
Friday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 67. South southeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 50%.
Saturday
A chance of showers, then showers and possibly a thunderstorm after noon. High near 84. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 80%.
Saturday Night
Showers likely and possibly a thunderstorm. Cloudy, with a low around 63. Chance of precipitation is 70%.
Sunday
Showers likely and possibly a thunderstorm. Cloudy, with a high near 78. Chance of precipitation is 70%.
Sunday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63.
Monday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 82.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
6:42 am CST Mar 3, 2026
Forecast Valid:
9am CST Mar 3, 2026-6pm CDT Mar 9, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation