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

75°F

24°C

Humidity 26%
Wind Speed E 13 G 17 mph
Barometer 30.03 in (1016.3 mb)
Dewpoint 38°F (3°C)
Visibility 10.00 mi
Last update 7 Apr 4:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Partly cloudy, with a low around 53. East wind around 5 mph becoming calm after midnight.

    Low: 53 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 79. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 79 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 60. Southeast wind around 5 mph becoming calm after midnight.

    Low: 60 °F

    Increasing
    Clouds

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 82. Light east wind becoming southeast 5 to 10 mph in the morning.

    High: 82 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A 30 percent chance of showers and thunderstorms, mainly before 1am. Mostly cloudy, with a low around 64. Southeast wind 5 to 10 mph.

    Low: 64 °F

    Chance
    T-storms

  • Friday

    Friday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    High: 78 °F

    Chance
    T-storms then
    Showers
    Likely

  • Friday Night

    Friday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 65. Southeast wind 5 to 10 mph.

    Low: 65 °F

    Slight Chance
    T-storms

  • Saturday

    Saturday: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 80. Southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 80 °F

    Chance
    Showers then
    Chance
    T-storms

  • Saturday Night

    Saturday Night: A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 68. Southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 68 °F

    Chance
    T-storms

Detailed Forecast

Tonight
Partly cloudy, with a low around 53. East wind around 5 mph becoming calm after midnight.
Wednesday
Mostly sunny, with a high near 79. Calm wind becoming southeast around 5 mph in the afternoon.
Wednesday Night
Increasing clouds, with a low around 60. Southeast wind around 5 mph becoming calm after midnight.
Thursday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 82. Light east wind becoming southeast 5 to 10 mph in the morning.
Thursday Night
A 30 percent chance of showers and thunderstorms, mainly before 1am. Mostly cloudy, with a low around 64. Southeast wind 5 to 10 mph.
Friday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Friday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 65. Southeast wind 5 to 10 mph.
Saturday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 80. Southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday Night
A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 68. Southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 80.
Sunday Night
A 20 percent chance of showers and thunderstorms. Cloudy, with a low around 69.
Monday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 83.
Monday Night
Mostly cloudy, with a low around 67.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82.
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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:
4:44 pm CDT Apr 7, 2026
Forecast Valid:
5pm CDT Apr 7, 2026-6pm CDT Apr 14, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation