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

56°F

13°C

Humidity 90%
Wind Speed N 14 mph
Barometer 30.09 in (1018.3 mb)
Dewpoint 53°F (12°C)
Visibility 10.00 mi
Last update 7 Mar 10:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: A slight chance of showers and thunderstorms before midnight, then a chance of showers and thunderstorms after 3am. Some of the storms could be severe. Mostly cloudy, with a low around 56. North wind around 10 mph. Chance of precipitation is 50%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    Low: 56 °F

    Severe
    Thunderstorms
    then Chance
    Showers

  • Sunday

    Sunday: A 40 percent chance of showers and thunderstorms, mainly after 3pm. Mostly cloudy, with a high near 70. North wind 5 to 10 mph.

    High: 70 °F

    Chance
    T-storms

  • Sunday Night

    Sunday Night: A 20 percent chance of showers and thunderstorms before midnight. Cloudy, with a low around 61. Northeast wind around 5 mph becoming calm.

    Low: 61 °F

    Slight Chance
    T-storms then
    Cloudy

  • Monday

    Monday: A chance of showers, with thunderstorms also possible after noon. Cloudy, with a high near 81. Light southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph. Chance of precipitation is 30%.

    High: 81 °F

    Chance
    Showers

  • Monday Night

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

    Low: 68 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Tuesday

    Tuesday: A chance of showers before noon, then a chance of showers and thunderstorms between noon and 3pm, then a chance of showers after 3pm. Cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    High: 83 °F

    Chance
    Showers

  • Tuesday Night

    Tuesday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 62. South southeast wind 15 to 20 mph decreasing to 5 to 10 mph after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 70%.

    Low: 62 °F

    Showers
    Likely

  • Wednesday

    Wednesday: A 40 percent chance of showers, mainly before noon. Sunny, with a high near 84. Southwest wind 5 to 15 mph becoming north northwest in the afternoon. Winds could gust as high as 25 mph.

    High: 84 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers before midnight. Mostly clear, with a low around 51. North wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 51 °F

    Slight Chance
    Showers then
    Clear

Detailed Forecast

Tonight
A slight chance of showers and thunderstorms before midnight, then a chance of showers and thunderstorms after 3am. Some of the storms could be severe. Mostly cloudy, with a low around 56. North wind around 10 mph. Chance of precipitation is 50%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Sunday
A 40 percent chance of showers and thunderstorms, mainly after 3pm. Mostly cloudy, with a high near 70. North wind 5 to 10 mph.
Sunday Night
A 20 percent chance of showers and thunderstorms before midnight. Cloudy, with a low around 61. Northeast wind around 5 mph becoming calm.
Monday
A chance of showers, with thunderstorms also possible after noon. Cloudy, with a high near 81. Light southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph. Chance of precipitation is 30%.
Monday Night
A 20 percent chance of showers after midnight. Cloudy, with a low around 68. South southeast wind around 10 mph.
Tuesday
A chance of showers before noon, then a chance of showers and thunderstorms between noon and 3pm, then a chance of showers after 3pm. Cloudy, with a high near 83. South wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.
Tuesday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 62. South southeast wind 15 to 20 mph decreasing to 5 to 10 mph after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 70%.
Wednesday
A 40 percent chance of showers, mainly before noon. Sunny, with a high near 84. Southwest wind 5 to 15 mph becoming north northwest in the afternoon. Winds could gust as high as 25 mph.
Wednesday Night
A 20 percent chance of showers before midnight. Mostly clear, with a low around 51. North wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday
Sunny, with a high near 71.
Thursday Night
Clear, with a low around 47.
Friday
Sunny, with a high near 79.
Friday Night
Clear, with a low around 57.
Saturday
Mostly sunny, with a high near 86.
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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:
10:32 pm CST Mar 7, 2026
Forecast Valid:
10pm CST Mar 7, 2026-6pm CDT Mar 14, 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