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

81°F

27°C

Humidity 41%
Wind Speed S 20 mph
Barometer 29.97 in (1014.3 mb)
Dewpoint 55°F (13°C)
Visibility 10.00 mi
Heat Index81°F (27°C)
Last update 1 Mar 5:56 pm CST
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Increasing clouds, with a low around 63. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Monday

    Monday: Cloudy through mid morning, then gradual clearing, with a high near 83. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 83 °F

    Gradual
    Clearing

  • Monday Night

    Monday Night: Increasing clouds, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Cloudy through mid morning, then gradual clearing, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 87 °F

    Gradual
    Clearing

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 66 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A chance of showers, with thunderstorms also possible after 9am. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.

    High: 86 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 66 °F

    Chance
    T-storms then
    Chance
    Showers

  • Thursday

    Thursday: A 20 percent chance of showers before noon. Partly sunny, with a high near 86. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 86 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 67 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

Detailed Forecast

Tonight
Increasing clouds, with a low around 63. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Cloudy through mid morning, then gradual clearing, with a high near 83. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Increasing clouds, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Cloudy through mid morning, then gradual clearing, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
A chance of showers, with thunderstorms also possible after 9am. Mostly cloudy, with a high near 86. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.
Wednesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 66. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday
A 20 percent chance of showers before noon. Partly sunny, with a high near 86. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Thursday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
A 40 percent chance of showers. Partly sunny, with a high near 85.
Friday Night
Showers likely. Mostly cloudy, with a low around 64. Chance of precipitation is 60%.
Saturday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 78. Chance of precipitation is 70%.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 59. Chance of precipitation is 60%.
Sunday
Showers and thunderstorms likely. Mostly cloudy, with a high near 74. Chance of precipitation is 60%.
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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:
5:44 pm CST Mar 1, 2026
Forecast Valid:
6pm CST Mar 1, 2026-6pm CDT Mar 8, 2026
 
Forecast Discussion
 
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Additional Resources

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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