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

82°F

28°C

Humidity 60%
Wind Speed SE 20 G 29 mph
Barometer 29.91 in (1012.0 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 14 Apr 6:56 pm CDT
Extended Forecast for

4 Miles SSW San Marcos TX

  • Tonight

    Tonight: Mostly cloudy, with a low around 68. South wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 68 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 84. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 68. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 68 °F

    Slight Chance
    T-storms

  • Thursday

    Thursday: Partly sunny, with a high near 88. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 88 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 68. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 68 °F

    Partly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 88. South wind 10 to 20 mph, with gusts as high as 30 mph.

    High: 88 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 68. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.

    Low: 68 °F

    Mostly Cloudy

  • Saturday

    Saturday: A 50 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 79. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph.

    High: 79 °F

    Slight Chance
    T-storms then
    Chance
    T-storms

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly cloudy, with a low around 55. North northeast wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 40%.

    Low: 55 °F

    Chance
    T-storms

Detailed Forecast

Tonight
Mostly cloudy, with a low around 68. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 84. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 68. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
Partly sunny, with a high near 88. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Partly cloudy, with a low around 68. South southeast wind around 10 mph, with gusts as high as 20 mph.
Friday
Mostly cloudy, with a high near 88. South wind 10 to 20 mph, with gusts as high as 30 mph.
Friday Night
Mostly cloudy, with a low around 68. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.
Saturday
A 50 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 79. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph.
Saturday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly cloudy, with a low around 55. North northeast wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 40%.
Sunday
A 20 percent chance of showers after 1pm. Mostly cloudy, with a high near 72.
Sunday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 56.
Monday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 69.
Monday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 59.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 77.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SSW San Marcos TX
 29.83°N 97.94°W (Elev. 610 ft)
Last Update:
6:46 pm CDT Apr 14, 2026
Forecast Valid:
6pm CDT Apr 14, 2026-6pm CDT Apr 21, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation