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

74°F

23°C

Humidity 85%
Wind Speed SE 8 mph
Barometer 29.91 in (1012.2 mb)
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Last update 7 Mar 1:56 am CST
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Cloudy, with a low around 70. South wind around 10 mph.

    Low: 70 °F

    Cloudy

  • Saturday

    Saturday: A chance of showers before noon, then a chance of showers and thunderstorms between noon and 3pm, then showers and possibly a thunderstorm after 3pm. High near 83. South southeast wind around 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 83 °F

    Chance
    Showers then
    Showers

  • Saturday Night

    Saturday Night: Showers and thunderstorms likely, mainly before 9pm. Cloudy, with a low around 56. North wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 56 °F

    T-storms
    Likely

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm before noon, then a chance of showers and thunderstorms after noon. Cloudy, with a high near 70. North wind 5 to 10 mph. Chance of precipitation is 60%.

    High: 70 °F

    Showers
    Likely then
    Chance
    T-storms

  • Sunday Night

    Sunday Night: A chance of showers and thunderstorms before 9pm, then a chance of showers between 9pm and midnight, then a slight chance of showers and thunderstorms after midnight. Cloudy, with a low around 62. Northeast wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 62 °F

    Chance
    Showers then
    Slight Chance
    T-storms

  • Monday

    Monday: A chance of showers, with thunderstorms also possible after 9am. Cloudy, with a high near 83. Light southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph. Chance of precipitation is 40%.

    High: 83 °F

    Chance
    Showers

  • Monday Night

    Monday Night: A 20 percent chance of showers and thunderstorms after midnight. Cloudy, with a low around 68. South southeast wind around 10 mph.

    Low: 68 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Tuesday

    Tuesday: A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 82 °F

    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 62. South southeast wind 5 to 15 mph becoming southwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 70%.

    Low: 62 °F

    Showers
    Likely

Detailed Forecast

Overnight
Cloudy, with a low around 70. South wind around 10 mph.
Saturday
A chance of showers before noon, then a chance of showers and thunderstorms between noon and 3pm, then showers and possibly a thunderstorm after 3pm. High near 83. South southeast wind around 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Saturday Night
Showers and thunderstorms likely, mainly before 9pm. Cloudy, with a low around 56. North wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.
Sunday
Showers likely and possibly a thunderstorm before noon, then a chance of showers and thunderstorms after noon. Cloudy, with a high near 70. North wind 5 to 10 mph. Chance of precipitation is 60%.
Sunday Night
A chance of showers and thunderstorms before 9pm, then a chance of showers between 9pm and midnight, then a slight chance of showers and thunderstorms after midnight. Cloudy, with a low around 62. Northeast wind around 5 mph becoming calm in the evening. Chance of precipitation is 30%.
Monday
A chance of showers, with thunderstorms also possible after 9am. Cloudy, with a high near 83. Light southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph. Chance of precipitation is 40%.
Monday Night
A 20 percent chance of showers and thunderstorms after midnight. Cloudy, with a low around 68. South southeast wind around 10 mph.
Tuesday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 30 mph.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 62. South southeast wind 5 to 15 mph becoming southwest after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 70%.
Wednesday
A 30 percent chance of showers, mainly before noon. Sunny, with a high near 80.
Wednesday Night
A 20 percent chance of showers and thunderstorms. Mostly clear, with a low around 51.
Thursday
Sunny, with a high near 69.
Thursday Night
Clear, with a low around 46.
Friday
Sunny, with a high near 77.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
1:44 am CST Mar 7, 2026
Forecast Valid:
2am CST Mar 7, 2026-6pm CDT Mar 13, 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