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

59°F

15°C

Humidity 60%
Wind Speed N 14 mph
Barometer 30.33 in (1026.6 mb)
Dewpoint 45°F (7°C)
Visibility 10.00 mi
Last update 6 Apr 8:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Sunny, with a high near 72. Northeast wind around 10 mph, with gusts as high as 20 mph.

    High: 72 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 48. North northeast wind around 5 mph.

    Low: 48 °F

    Mostly Clear

  • Tuesday

    Tuesday: Partly sunny, with a high near 75. Calm wind becoming east southeast around 5 mph in the morning.

    High: 75 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 55. East southeast wind around 5 mph becoming calm after midnight.

    Low: 55 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 77. Calm wind becoming southeast around 5 mph in the morning.

    High: 77 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 61. South southeast wind around 5 mph.

    Low: 61 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly cloudy, with a high near 81. Calm wind becoming southeast around 5 mph in the morning.

    High: 81 °F

    Mostly Cloudy

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 63. Southeast wind around 5 mph.

    Low: 63 °F

    Mostly Cloudy

  • Friday

    Friday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 81. East southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 81 °F

    Cloudy then
    Slight Chance
    T-storms

Detailed Forecast

Today
Sunny, with a high near 72. Northeast wind around 10 mph, with gusts as high as 20 mph.
Tonight
Mostly clear, with a low around 48. North northeast wind around 5 mph.
Tuesday
Partly sunny, with a high near 75. Calm wind becoming east southeast around 5 mph in the morning.
Tuesday Night
Partly cloudy, with a low around 55. East southeast wind around 5 mph becoming calm after midnight.
Wednesday
Partly sunny, with a high near 77. Calm wind becoming southeast around 5 mph in the morning.
Wednesday Night
Mostly cloudy, with a low around 61. South southeast wind around 5 mph.
Thursday
Mostly cloudy, with a high near 81. Calm wind becoming southeast around 5 mph in the morning.
Thursday Night
Mostly cloudy, with a low around 63. Southeast wind around 5 mph.
Friday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 81. East southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Mostly cloudy, with a low around 66.
Saturday
A 40 percent chance of showers and thunderstorms. Cloudy, with a high near 81.
Saturday Night
A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 68.
Sunday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 82.
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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:
6:42 am CDT Apr 6, 2026
Forecast Valid:
9am CDT Apr 6, 2026-6pm CDT Apr 12, 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