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.

Overcast

77°F

25°C

Humidity 74%
Wind Speed S 16 mph
Barometer 30.04 in (1016.7 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 14 Apr 11:56 am CDT
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Patchy drizzle before 4pm. Partly sunny, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 83 °F

    Patchy
    Drizzle

  • Tonight

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

    Low: 68 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 83 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Wednesday Night

    Wednesday Night: A 30 percent chance of showers and thunderstorms, mainly before 7pm. Mostly cloudy, with a low around 67. South southeast wind 5 to 10 mph.

    Low: 67 °F

    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 67. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 67 °F

    Partly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 88. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 88 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 67 °F

    Mostly Cloudy

  • Saturday

    Saturday: A 50 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 78. South wind 5 to 10 mph becoming north northwest in the morning. Winds could gust as high as 20 mph.

    High: 78 °F

    Slight Chance
    T-storms then
    Chance
    T-storms

Detailed Forecast

This Afternoon
Patchy drizzle before 4pm. Partly sunny, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tonight
Increasing clouds, with a low around 68. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A 30 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Mostly cloudy, with a low around 67. South southeast wind 5 to 10 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 67. 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 15 mph, with gusts as high as 30 mph.
Friday Night
Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Saturday
A 50 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 78. South wind 5 to 10 mph becoming north northwest in the morning. Winds could gust as high as 20 mph.
Saturday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly cloudy, with a low around 57. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers. Mostly cloudy, with a high near 71.
Sunday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 57.
Monday
A 30 percent chance of showers. Mostly cloudy, with a high near 71.
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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:
11:44 am CDT Apr 14, 2026
Forecast Valid:
12pm CDT Apr 14, 2026-6pm CDT Apr 20, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation