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.

Partly Cloudy

78°F

26°C

Humidity 54%
Wind Speed SE 3 mph
Barometer 30.05 in (1017.2 mb)
Dewpoint 60°F (16°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 12 Feb 4:56 pm CST
Extended Forecast for

San Marcos Municipal Airport TX

  • Tonight

    Tonight: Increasing clouds, with a low around 59. South wind around 5 mph becoming calm after midnight.

    Low: 59 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, with a high near 81. Light south wind becoming south southeast 10 to 15 mph in the morning. Winds could gust as high as 20 mph.

    High: 81 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: A 50 percent chance of showers after midnight. Mostly cloudy, with a low around 62. Southeast wind 10 to 15 mph, with gusts as high as 20 mph. New precipitation amounts of less than a tenth of an inch possible.

    Low: 62 °F

    Mostly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: Showers, with thunderstorms also possible after noon. High near 76. South southeast wind 10 to 15 mph becoming west southwest in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.

    High: 76 °F

    Showers

  • Saturday Night

    Saturday Night: A slight chance of showers and thunderstorms before 9pm, then a slight chance of showers between 9pm and midnight. Mostly clear, with a low around 55. West wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    Low: 55 °F

    Slight Chance
    T-storms then
    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 75. North northwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 75 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 46. North wind 5 to 10 mph becoming light in the evening.

    Low: 46 °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 50. South southeast wind around 5 mph.

    Low: 50 °F

    Mostly Clear

Detailed Forecast

Tonight
Increasing clouds, with a low around 59. South wind around 5 mph becoming calm after midnight.
Friday
Mostly cloudy, with a high near 81. Light south wind becoming south southeast 10 to 15 mph in the morning. Winds could gust as high as 20 mph.
Friday Night
A 50 percent chance of showers after midnight. Mostly cloudy, with a low around 62. Southeast wind 10 to 15 mph, with gusts as high as 20 mph. New precipitation amounts of less than a tenth of an inch possible.
Saturday
Showers, with thunderstorms also possible after noon. High near 76. South southeast wind 10 to 15 mph becoming west southwest in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.
Saturday Night
A slight chance of showers and thunderstorms before 9pm, then a slight chance of showers between 9pm and midnight. Mostly clear, with a low around 55. West wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Sunday
Sunny, with a high near 75. North northwest wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 46. North wind 5 to 10 mph becoming light 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 50. South southeast wind around 5 mph.
Tuesday
Mostly sunny, with a high near 83.
Tuesday Night
Partly cloudy, with a low around 56.
Wednesday
Partly sunny, with a high near 84.
Wednesday Night
Mostly cloudy, with a low around 57.
Thursday
Partly sunny, with a high near 82.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
4:32 pm CST Feb 12, 2026
Forecast Valid:
5pm CST Feb 12, 2026-6pm CST Feb 19, 2026
 
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Additional Resources

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Chance of Precipitation