National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

67°F

19°C

Humidity 71%
Wind Speed NW 5 mph
Barometer 30.03 in (1016.3 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Last update 10 Oct 8:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 90. Calm wind becoming south around 5 mph in the afternoon.

    High: 90 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 66. South southeast wind around 5 mph.

    Low: 66 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 91. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.

    Low: 72 °F

    Partly Cloudy

  • Columbus Day

    Columbus Day: A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 91 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Monday Night

    Monday Night: Partly cloudy, with a low around 74. South wind around 5 mph.

    Low: 74 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 93 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 92. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 92 °F

    Mostly Sunny

Detailed Forecast

Today
Sunny, with a high near 90. Calm wind becoming south around 5 mph in the afternoon.
Tonight
Mostly clear, with a low around 66. South southeast wind around 5 mph.
Sunday
Sunny, with a high near 91. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.
Columbus Day
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Partly cloudy, with a low around 74. South wind around 5 mph.
Tuesday
Mostly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 75. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Mostly sunny, with a high near 92. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Partly cloudy, with a low around 74.
Thursday
A 30 percent chance of showers. Mostly sunny, with a high near 90.
Thursday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 70.
Friday
A 20 percent chance of showers. Mostly sunny, with a high near 83.
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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:
8:44 am CDT Oct 10, 2026
Forecast Valid:
9am CDT Oct 10, 2026-6pm CDT Oct 16, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation