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.

Heavy Rain Fog/Mist

59°F

15°C

Humidity 96%
Wind Speed N 18 mph
Barometer 30.13 in (1019.7 mb)
Dewpoint 58°F (14°C)
Visibility 5.00 mi
Last update 4 Apr 2:56 pm CDT
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Showers and possibly a thunderstorm before 4pm, then a chance of showers and thunderstorms after 4pm. High near 79. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    High: 79 °F

    T-storms

  • Tonight

    Tonight: A chance of showers and thunderstorms before 10pm, then a slight chance of showers after 1am. Mostly cloudy, with a low around 54. North northeast wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 30%.

    Low: 54 °F

    Chance
    T-storms then
    Slight Chance
    Showers

  • Sunday

    Sunday: A 20 percent chance of showers before 10am. Mostly cloudy, with a high near 67. North northeast wind 15 to 20 mph, with gusts as high as 30 mph.

    High: 67 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Sunday Night

    Sunday Night: A 20 percent chance of showers before 1am. Cloudy, with a low around 54. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 54 °F

    Slight Chance
    Showers

  • Monday

    Monday: Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.

    High: 70 °F

    Partly Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 49. East northeast wind around 5 mph.

    Low: 49 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 70. East wind around 5 mph.

    High: 70 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 51. East wind around 5 mph becoming calm in the evening.

    Low: 51 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 75. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 75 °F

    Partly Sunny

Detailed Forecast

This Afternoon
Showers and possibly a thunderstorm before 4pm, then a chance of showers and thunderstorms after 4pm. High near 79. North wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Tonight
A chance of showers and thunderstorms before 10pm, then a slight chance of showers after 1am. Mostly cloudy, with a low around 54. North northeast wind around 15 mph, with gusts as high as 30 mph. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers before 10am. Mostly cloudy, with a high near 67. North northeast wind 15 to 20 mph, with gusts as high as 30 mph.
Sunday Night
A 20 percent chance of showers before 1am. Cloudy, with a low around 54. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.
Monday Night
Partly cloudy, with a low around 49. East northeast wind around 5 mph.
Tuesday
Mostly cloudy, with a high near 70. East wind around 5 mph.
Tuesday Night
Mostly cloudy, with a low around 51. East wind around 5 mph becoming calm in the evening.
Wednesday
Partly sunny, with a high near 75. Calm wind becoming southeast around 5 mph in the afternoon.
Wednesday Night
Mostly cloudy, with a low around 59.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81.
Thursday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63.
Friday
A 40 percent chance of showers and thunderstorms. 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:
2:46 pm CDT Apr 4, 2026
Forecast Valid:
3pm CDT Apr 4, 2026-6pm CDT Apr 10, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation