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.

Fog/Mist

75°F

24°C

Humidity 94%
Wind Speed N 12 mph
Barometer 30.04 in (1016.6 mb)
Dewpoint 73°F (23°C)
Visibility 2.00 mi
Last update 3 Oct 10:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 30%.

    High: 81 °F

    Chance
    Showers

  • Tonight

    Tonight: A chance of showers before 7pm, then a slight chance of showers after 1am. Partly cloudy, with a low around 71. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 30%.

    Low: 71 °F

    Chance
    Showers

  • Sunday

    Sunday: A 20 percent chance of showers before 10am. Mostly cloudy, with a high near 82. North wind around 15 mph, with gusts as high as 25 mph.

    High: 82 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 71. North wind around 10 mph, with gusts as high as 25 mph.

    Low: 71 °F

    Mostly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 84. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 64. North wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 64 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 85. North northeast wind 5 to 10 mph.

    High: 85 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 63. Northeast wind around 5 mph becoming calm.

    Low: 63 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 86. Northeast wind around 5 mph.

    High: 86 °F

    Sunny

Detailed Forecast

Today
A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 30%.
Tonight
A chance of showers before 7pm, then a slight chance of showers after 1am. Partly cloudy, with a low around 71. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers before 10am. Mostly cloudy, with a high near 82. North wind around 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly cloudy, with a low around 71. North wind around 10 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 84. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.
Monday Night
Mostly clear, with a low around 64. North wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Sunny, with a high near 85. North northeast wind 5 to 10 mph.
Tuesday Night
Clear, with a low around 63. Northeast wind around 5 mph becoming calm.
Wednesday
Sunny, with a high near 86. Northeast wind around 5 mph.
Wednesday Night
Clear, with a low around 64.
Thursday
Sunny, with a high near 88.
Thursday Night
Mostly clear, with a low around 65.
Friday
A 20 percent chance of showers. Sunny, with a high near 87.
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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:
9:44 am CDT Oct 3, 2026
Forecast Valid:
11am CDT Oct 3, 2026-6pm CDT Oct 9, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

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