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

74°F

23°C

Humidity 97%
Wind Speed SW 5 mph
Barometer 29.93 in (1012.7 mb)
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Last update 17 Jun 12:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Mostly clear, with a low around 73. South wind 5 to 10 mph.

    Low: 73 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 95. Heat index values as high as 103. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 75. South wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Mostly cloudy, then gradually becoming sunny, with a high near 95. Heat index values as high as 104. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Decreasing
    Clouds

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Partly Cloudy

  • Juneteenth

    Juneteenth: Mostly sunny, with a high near 94. South southeast wind 5 to 10 mph.

    High: 94 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 74. Southeast wind 5 to 10 mph.

    Low: 74 °F

    Partly Cloudy

  • Friday

    Friday: 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

  • Friday Night

    Friday Night: Mostly clear, with a low around 74. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Mostly Clear

Detailed Forecast

Overnight
Mostly clear, with a low around 73. South wind 5 to 10 mph.
Tuesday
Mostly sunny, with a high near 95. Heat index values as high as 103. South wind 5 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Increasing clouds, with a low around 75. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
Mostly cloudy, then gradually becoming sunny, with a high near 95. Heat index values as high as 104. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
Partly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Juneteenth
Mostly sunny, with a high near 94. South southeast wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 74. Southeast wind 5 to 10 mph.
Friday
Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Mostly clear, with a low around 74. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday
Mostly sunny, with a high near 94.
Saturday Night
Partly cloudy, with a low around 74.
Sunday
Mostly sunny, with a high near 93.
Sunday Night
Partly cloudy, with a low around 74.
Monday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 93.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
12:50 am CDT Jun 17, 2025
Forecast Valid:
1am CDT Jun 17, 2025-6pm CDT Jun 23, 2025
 
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Additional Resources

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Chance of Precipitation