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.

A Few Clouds

89°F

32°C

Humidity 59%
Wind Speed SW 10 mph
Barometer 30.13 in (1019.5 mb)
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index97°F (36°C)
Last update 8 Jul 10:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 95. Heat index values as high as 101. South wind 5 to 10 mph.

    High: 95 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 74. South wind 5 to 10 mph.

    Low: 74 °F

    Mostly Clear

  • Thursday

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

    High: 95 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 75. South wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Mostly Clear

  • Friday

    Friday: A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Mostly Sunny
    then Chance
    T-storms

  • Friday Night

    Friday Night: A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Clear
    then Slight
    Chance
    T-storms

  • Saturday

    Saturday: A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 93. South southeast wind 5 to 10 mph.

    High: 93 °F

    Mostly Sunny
    then Chance
    T-storms

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 76. South southeast wind 5 to 10 mph.

    Low: 76 °F

    Partly Cloudy

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 94. Light south wind becoming south southeast 5 to 10 mph in the morning.

    High: 94 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

Detailed Forecast

Today
Sunny, with a high near 95. Heat index values as high as 101. South wind 5 to 10 mph.
Tonight
Mostly clear, with a low around 74. South wind 5 to 10 mph.
Thursday
Sunny, with a high near 95. Heat index values as high as 100. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Mostly clear, with a low around 75. South wind 5 to 15 mph, with gusts as high as 25 mph.
Friday
A 30 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday
A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 93. South southeast wind 5 to 10 mph.
Saturday Night
Partly cloudy, with a low around 76. South southeast wind 5 to 10 mph.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 94. Light south wind becoming south southeast 5 to 10 mph in the morning.
Sunday Night
A 20 percent chance of showers before 1am. Partly cloudy, with a low around 76.
Monday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 94.
Monday Night
A 20 percent chance of showers. Partly cloudy, with a low around 76.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly sunny, with a high near 94.
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Forecast Area
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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 CDT Jul 8, 2026
Forecast Valid:
11am CDT Jul 8, 2026-6pm CDT Jul 14, 2026
 
Forecast Discussion
 
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Additional Resources

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