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.

Mostly Cloudy

79°F

26°C

Humidity 50%
Wind Speed S 17 mph
Barometer 29.97 in (1014.2 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Heat Index80°F (27°C)
Last update 13 Feb 3:56 pm CST
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: A 30 percent chance of showers after 3am. Increasing clouds, with a low around 64. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 64 °F

    Mostly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: Showers, with thunderstorms also possible after noon. High near 75. South southeast wind around 10 mph becoming west in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 75 °F

    Showers

  • Saturday Night

    Saturday Night: A 20 percent chance of showers before midnight. Mostly cloudy, then gradually becoming clear, with a low around 56. West wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 56 °F

    Slight Chance
    Showers then
    Clear

  • Sunday

    Sunday: Sunny, with a high near 76. North northwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 76 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 48. North wind around 5 mph becoming calm in the evening.

    Low: 48 °F

    Mostly Clear

  • Washington's Birthday

    Washington's Birthday: Sunny, with a high near 78. Calm wind becoming south around 5 mph in the afternoon.

    High: 78 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 52. South southeast wind around 5 mph.

    Low: 52 °F

    Mostly Clear

  • Tuesday

    Tuesday: Partly sunny, with a high near 83. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 83 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 58. South wind 5 to 10 mph.

    Low: 58 °F

    Partly Cloudy

Detailed Forecast

Tonight
A 30 percent chance of showers after 3am. Increasing clouds, with a low around 64. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Showers, with thunderstorms also possible after noon. High near 75. South southeast wind around 10 mph becoming west in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Saturday Night
A 20 percent chance of showers before midnight. Mostly cloudy, then gradually becoming clear, with a low around 56. West wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 76. North northwest wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 48. North wind around 5 mph becoming calm in the evening.
Washington's Birthday
Sunny, with a high near 78. Calm wind becoming south around 5 mph in the afternoon.
Monday Night
Mostly clear, with a low around 52. South southeast wind around 5 mph.
Tuesday
Partly sunny, with a high near 83. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 58. South wind 5 to 10 mph.
Wednesday
Partly sunny, with a high near 84.
Wednesday Night
Partly cloudy, with a low around 58.
Thursday
Partly sunny, with a high near 85.
Thursday Night
Mostly cloudy, with a low around 59.
Friday
Partly sunny, with a high near 82.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
4:32 pm CST Feb 13, 2026
Forecast Valid:
4pm CST Feb 13, 2026-6pm CST Feb 20, 2026
 
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Additional Resources

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Chance of Precipitation