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

92°F

33°C

Humidity 58%
Wind Speed SE 14 mph
Barometer 30.00 in (1015.0 mb)
Dewpoint 75°F (24°C)
Visibility 10.00 mi
Heat Index103°F (39°C)
Last update 19 Jun 6:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Friday

    Friday: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 93. Heat index values as high as 100. South wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 93 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Friday Night

    Friday Night: Partly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 93. Heat index values as high as 100. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 93 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 74. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 74 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 94. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 94 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 74. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 74 °F

    Mostly Clear

  • Monday

    Monday: Mostly sunny, with a high near 94. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 73. Southeast wind 5 to 15 mph, with gusts as high as 20 mph.

    Low: 73 °F

    Partly Cloudy

Detailed Forecast

Tonight
Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Friday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 93. Heat index values as high as 100. South wind 5 to 15 mph, with gusts as high as 20 mph.
Friday Night
Partly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Mostly sunny, with a high near 93. Heat index values as high as 100. South wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Partly cloudy, with a low around 74. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday
Mostly sunny, with a high near 94. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 74. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 94. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Partly cloudy, with a low around 73. Southeast wind 5 to 15 mph, with gusts as high as 20 mph.
Tuesday
Mostly sunny, with a high near 94.
Tuesday Night
Mostly clear, with a low around 73.
Wednesday
Mostly sunny, with a high near 94.
Wednesday Night
Partly cloudy, with a low around 72.
Thursday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 93.
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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:
6:32 pm CDT Jun 19, 2025
Forecast Valid:
7pm CDT Jun 19, 2025-6pm CDT Jun 26, 2025
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation