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

75°F

24°C

Humidity 69%
Wind Speed SW 3 mph
Barometer 29.92 in (1012.4 mb)
Dewpoint 64°F (18°C)
Visibility 10.00 mi
Last update 23 May 7:56 am CDT
Extended Forecast for

4 Miles W San Marcos TX

  • Today

    Today: Sunny, with a high near 95. Heat index values as high as 100. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 95 °F

    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 73. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 73 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Mostly cloudy, then gradually becoming sunny, with a high near 97. Heat index values as high as 102. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 97 °F

    Decreasing
    Clouds

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Mostly Cloudy

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 95. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Sunday Night

    Sunday Night: A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Slight Chance
    T-storms

  • Memorial Day

    Memorial Day: A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 93. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 93 °F

    Chance
    T-storms

  • Monday Night

    Monday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 71 °F

    Chance
    T-storms

  • Tuesday

    Tuesday: A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 90. East southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 90 °F

    Chance
    T-storms

Detailed Forecast

Today
Sunny, with a high near 95. Heat index values as high as 100. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tonight
Increasing clouds, with a low around 73. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Mostly cloudy, then gradually becoming sunny, with a high near 97. Heat index values as high as 102. South wind 10 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Mostly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 95. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Memorial Day
A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 93. South wind 10 to 15 mph, with gusts as high as 25 mph.
Monday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 71. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 90. East southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 69.
Wednesday
A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 89.
Wednesday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 70.
Thursday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 89.
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles W San Marcos TX
 29.88°N 97.99°W (Elev. 725 ft)
Last Update:
7:56 am CDT May 23, 2025
Forecast Valid:
8am CDT May 23, 2025-6pm CDT May 29, 2025
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation