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.

Overcast

73°F

23°C

Humidity 84%
Wind Speed N 12 mph
Barometer 30.10 in (1018.6 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Last update 5 Oct 3:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly sunny, with a high near 84. North northeast wind around 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 67. North wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 67 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 86. North northeast wind 5 to 10 mph.

    High: 86 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 66. Northeast wind around 5 mph becoming calm.

    Low: 66 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 88. Northeast wind around 5 mph.

    High: 88 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 67. East northeast wind around 5 mph becoming calm.

    Low: 67 °F

    Mostly Clear

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. Northeast wind around 5 mph.

    High: 89 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after 1am. Partly cloudy, with a low around 68. Northeast wind around 5 mph becoming calm in the evening.

    Low: 68 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Friday

    Friday: A slight chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 85. North northeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    High: 85 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

Detailed Forecast

Today
Mostly sunny, with a high near 84. North northeast wind around 15 mph, with gusts as high as 25 mph.
Tonight
Mostly clear, with a low around 67. North wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Sunny, with a high near 86. North northeast wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 66. Northeast wind around 5 mph becoming calm.
Wednesday
Sunny, with a high near 88. Northeast wind around 5 mph.
Wednesday Night
Mostly clear, with a low around 67. East northeast wind around 5 mph becoming calm.
Thursday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 89. Northeast wind around 5 mph.
Thursday Night
A 20 percent chance of showers after 1am. Partly cloudy, with a low around 68. Northeast wind around 5 mph becoming calm in the evening.
Friday
A slight chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 85. North northeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Friday Night
A 20 percent chance of showers before 1am. Partly cloudy, with a low around 65.
Saturday
Sunny, with a high near 87.
Saturday Night
Mostly clear, with a low around 67.
Sunday
Mostly sunny, with a high near 88.
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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:
2:44 am CDT Oct 5, 2026
Forecast Valid:
4am CDT Oct 5, 2026-6pm CDT Oct 11, 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