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

76°F

24°C

Humidity 77%
Wind Speed S 14 mph
Barometer 29.96 in (1013.8 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Heat Index77°F (25°C)
Last update 3 Apr 9:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly cloudy, with a high near 87. South southeast wind around 15 mph, with gusts as high as 30 mph.

    High: 87 °F

    Mostly Cloudy

  • Tonight

    Tonight: A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 69. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    Low: 69 °F

    Chance
    T-storms

  • Saturday

    Saturday: Showers and possibly a thunderstorm. High near 78. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    High: 78 °F

    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 54. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    Low: 54 °F

    Chance
    Showers

  • Sunday

    Sunday: A 30 percent chance of showers. Mostly cloudy, with a high near 66. North northeast wind around 15 mph, with gusts as high as 25 mph.

    High: 66 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: A 20 percent chance of showers. Cloudy, with a low around 52. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 52 °F

    Slight Chance
    Showers

  • Monday

    Monday: Mostly cloudy, with a high near 68. Northeast wind 5 to 10 mph.

    High: 68 °F

    Mostly Cloudy

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 50. Northeast wind around 5 mph becoming calm in the evening.

    Low: 50 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 71. North northeast wind around 5 mph becoming east southeast in the afternoon.

    High: 71 °F

    Mostly Cloudy

Detailed Forecast

Today
Mostly cloudy, with a high near 87. South southeast wind around 15 mph, with gusts as high as 30 mph.
Tonight
A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 69. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.
Saturday
Showers and possibly a thunderstorm. High near 78. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 54. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.
Sunday
A 30 percent chance of showers. Mostly cloudy, with a high near 66. North northeast wind around 15 mph, with gusts as high as 25 mph.
Sunday Night
A 20 percent chance of showers. Cloudy, with a low around 52. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Mostly cloudy, with a high near 68. Northeast wind 5 to 10 mph.
Monday Night
Mostly cloudy, with a low around 50. Northeast wind around 5 mph becoming calm in the evening.
Tuesday
Mostly cloudy, with a high near 71. North northeast wind around 5 mph becoming east southeast in the afternoon.
Tuesday Night
Mostly cloudy, with a low around 53.
Wednesday
Mostly cloudy, with a high near 76.
Wednesday Night
Mostly cloudy, with a low around 60.
Thursday
A 20 percent chance of showers. Mostly cloudy, with a high near 80.
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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 3, 2026
Forecast Valid:
10am CDT Apr 3, 2026-6pm CDT Apr 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