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.

Partly Cloudy

68°F

20°C

Humidity 81%
Wind Speed SE 13 mph
Barometer 30.11 in (1019.2 mb)
Dewpoint 62°F (17°C)
Visibility 10.00 mi
Last update 8 Apr 11:56 pm CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Mostly cloudy, with a low around 61. Southeast wind around 5 mph.

    Low: 61 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 50 percent chance of showers and thunderstorms after 1pm. Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 83. Light east southeast wind increasing to 5 to 10 mph in the morning. New rainfall amounts between a quarter and half of an inch possible.

    High: 83 °F

    Patchy Fog
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Southeast wind 5 to 10 mph. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 64 °F

    Chance
    T-storms

  • Friday

    Friday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 81. East southeast wind 5 to 10 mph. Chance of precipitation is 60%.

    High: 81 °F

    Chance
    T-storms then
    Showers
    Likely

  • Friday Night

    Friday Night: A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Mostly cloudy, with a low around 66. Southeast wind 5 to 10 mph. Chance of precipitation is 20%.

    Low: 66 °F

    Slight Chance
    T-storms then
    Slight Chance
    Showers

  • Saturday

    Saturday: A slight chance of showers, then a chance of showers and thunderstorms after 10am. Mostly cloudy, with a high near 82. Southeast wind 5 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.

    High: 82 °F

    Slight Chance
    T-storms then
    Chance
    T-storms

  • Saturday Night

    Saturday Night: A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 67 °F

    Chance
    Showers

  • Sunday

    Sunday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Cloudy, with a high near 80. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.

    High: 80 °F

    Chance
    Showers then
    Showers
    Likely

  • Sunday Night

    Sunday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 69. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 69 °F

    Slight Chance
    T-storms

Detailed Forecast

Overnight
Mostly cloudy, with a low around 61. Southeast wind around 5 mph.
Thursday
A 50 percent chance of showers and thunderstorms after 1pm. Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 83. Light east southeast wind increasing to 5 to 10 mph in the morning. New rainfall amounts between a quarter and half of an inch possible.
Thursday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Southeast wind 5 to 10 mph. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Friday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 81. East southeast wind 5 to 10 mph. Chance of precipitation is 60%.
Friday Night
A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Mostly cloudy, with a low around 66. Southeast wind 5 to 10 mph. Chance of precipitation is 20%.
Saturday
A slight chance of showers, then a chance of showers and thunderstorms after 10am. Mostly cloudy, with a high near 82. Southeast wind 5 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.
Saturday Night
A 30 percent chance of showers and thunderstorms. Cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Cloudy, with a high near 80. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.
Sunday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 69. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Monday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 83.
Monday Night
Mostly cloudy, with a low around 69.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81.
Tuesday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 66.
Wednesday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 78.
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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:
12:44 am CDT Apr 9, 2026
Forecast Valid:
12am CDT Apr 9, 2026-6pm CDT Apr 15, 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