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.

A Few Clouds

63°F

17°C

Humidity 84%
Wind Speed S 9 mph
Barometer 30.11 in (1019.0 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 9 Feb 11:56 pm CST
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Mostly cloudy, with a low around 59. South wind 5 to 10 mph.

    Low: 59 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Patchy fog between 7am and 10am. Otherwise, cloudy, with a high near 74. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 74 °F

    Patchy Fog
    then Cloudy

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers, mainly between 9pm and 3am. Mostly cloudy, with a low around 58. Southeast wind around 5 mph becoming calm in the evening.

    Low: 58 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A 20 percent chance of showers before noon. Mostly cloudy, then gradually becoming sunny, with a high near 74. North wind around 5 mph.

    High: 74 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 57. Northeast wind around 5 mph becoming calm in the evening.

    Low: 57 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 80. Calm wind becoming south around 5 mph in the afternoon.

    High: 80 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 60. South wind around 5 mph.

    Low: 60 °F

    Partly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: A slight chance of showers, then showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 61. South southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    Low: 61 °F

    Slight Chance
    Showers then
    Showers
    Likely

Detailed Forecast

Overnight
Mostly cloudy, with a low around 59. South wind 5 to 10 mph.
Tuesday
Patchy fog between 7am and 10am. Otherwise, cloudy, with a high near 74. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
A 30 percent chance of showers, mainly between 9pm and 3am. Mostly cloudy, with a low around 58. Southeast wind around 5 mph becoming calm in the evening.
Wednesday
A 20 percent chance of showers before noon. Mostly cloudy, then gradually becoming sunny, with a high near 74. North wind around 5 mph.
Wednesday Night
Partly cloudy, with a low around 57. Northeast wind around 5 mph becoming calm in the evening.
Thursday
Partly sunny, with a high near 80. Calm wind becoming south around 5 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 60. South wind around 5 mph.
Friday
Mostly cloudy, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
A slight chance of showers, then showers likely and possibly a thunderstorm after midnight. Mostly cloudy, with a low around 61. South southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Saturday
Showers likely and possibly a thunderstorm before noon, then a chance of showers and thunderstorms after noon. Mostly sunny, with a high near 78. Chance of precipitation is 60%.
Saturday Night
Clear, with a low around 51.
Sunday
Sunny, with a high near 76.
Sunday Night
Clear, with a low around 46.
Washington's Birthday
Sunny, with a high near 78.
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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:
11:49 pm CST Feb 9, 2026
Forecast Valid:
12am CST Feb 10, 2026-6pm CST Feb 16, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation