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

76°F

24°C

Humidity 48%
Wind Speed S 7 mph
Barometer 30.18 in (1021.6 mb)
Dewpoint 55°F (13°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 12 Feb 11:56 am CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 80. South wind around 5 mph.

    High: 80 °F

    Mostly Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 60. South southeast wind around 5 mph.

    Low: 60 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, with a high near 80. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 80 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: A 50 percent chance of showers after midnight. Mostly cloudy, with a low around 63. Southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Mostly Cloudy
    then Chance
    Showers

  • Saturday

    Saturday: Showers, with thunderstorms also possible after noon. High near 76. South southeast wind around 10 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 56. West southwest wind 5 to 10 mph becoming northwest after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 20%.

    Low: 56 °F

    Slight Chance
    T-storms then
    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 47. North wind around 5 mph becoming calm in the evening.

    Low: 47 °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

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 80. South wind around 5 mph.
Tonight
Increasing clouds, with a low around 60. South southeast wind around 5 mph.
Friday
Mostly cloudy, with a high near 80. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
A 50 percent chance of showers after midnight. Mostly cloudy, with a low around 63. Southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Showers, with thunderstorms also possible after noon. High near 76. South southeast wind around 10 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 56. West southwest wind 5 to 10 mph becoming northwest after midnight. Winds could gust 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 47. 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 51.
Tuesday
Mostly sunny, with a high near 83.
Tuesday Night
Partly cloudy, with a low around 58.
Wednesday
Partly sunny, with a high near 83.
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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 CST Feb 12, 2026
Forecast Valid:
12pm CST Feb 12, 2026-6pm CST Feb 18, 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