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

85°F

29°C

Humidity 35%
Wind Speed NE 16 mph
Barometer 29.75 in (1006.7 mb)
Dewpoint 54°F (12°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 26 Feb 4:56 pm CST
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Mostly clear, with a low around 57. North northeast wind 5 to 10 mph.

    Low: 57 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 86. North wind around 5 mph becoming east in the afternoon.

    High: 86 °F

    Sunny

  • Friday Night

    Friday Night: Increasing clouds, with a low around 57. East wind around 5 mph becoming calm in the evening.

    Low: 57 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Partly sunny, then gradually becoming sunny, with a high near 86. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 86 °F

    Becoming
    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 59. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 59 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 85. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 85 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 60. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.

    Low: 60 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 79. South wind 5 to 10 mph becoming east in the afternoon. Winds could gust as high as 20 mph.

    High: 79 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 56. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 56 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly clear, with a low around 57. North northeast wind 5 to 10 mph.
Friday
Sunny, with a high near 86. North wind around 5 mph becoming east in the afternoon.
Friday Night
Increasing clouds, with a low around 57. East wind around 5 mph becoming calm in the evening.
Saturday
Partly sunny, then gradually becoming sunny, with a high near 86. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Saturday Night
Partly cloudy, with a low around 59. South wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday
Mostly sunny, with a high near 85. South wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Partly cloudy, with a low around 60. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.
Monday
Mostly sunny, with a high near 79. South wind 5 to 10 mph becoming east in the afternoon. Winds could gust as high as 20 mph.
Monday Night
Partly cloudy, with a low around 56. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Partly sunny, with a high near 84.
Tuesday Night
Mostly cloudy, with a low around 62.
Wednesday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 83.
Wednesday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 64.
Thursday
A 20 percent chance of showers. Mostly sunny, with a high near 85.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.91°W (Elev. 597 ft)
Last Update:
5:00 pm CST Feb 26, 2026
Forecast Valid:
5pm CST Feb 26, 2026-6pm CST Mar 5, 2026
 
Forecast Discussion
 
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Additional Resources

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