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

52°F

11°C

Humidity 83%
Wind Speed Calm
Barometer 29.96 in (1014.1 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Last update 28 Feb 4:56 am CST
Extended Forecast for

San Marcos TX

  • Today

    Today: Patchy fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Tonight

    Tonight: Patchy fog after 3am. Otherwise, increasing clouds, with a low around 60. South wind 5 to 10 mph.

    Low: 60 °F

    Mostly Clear
    then Patchy
    Fog

  • Sunday

    Sunday: Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 82. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 82 °F

    Patchy Fog
    then Sunny

  • Sunday Night

    Sunday Night: Increasing clouds, with a low around 61. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 61 °F

    Increasing
    Clouds

  • Monday

    Monday: Mostly sunny, with a high near 83. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 83 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 87 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 65 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: Showers likely, with thunderstorms also possible after noon. Mostly cloudy, with a high near 82. South southeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.

    High: 82 °F

    Showers
    Likely

Detailed Forecast

Today
Patchy fog before 9am. Otherwise, partly sunny, then gradually becoming sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tonight
Patchy fog after 3am. Otherwise, increasing clouds, with a low around 60. South wind 5 to 10 mph.
Sunday
Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 82. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Increasing clouds, with a low around 61. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 83. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Tuesday
Partly sunny, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
Showers likely, with thunderstorms also possible after noon. Mostly cloudy, with a high near 82. South southeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.
Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Chance of precipitation is 50%.
Thursday
A 40 percent chance of showers. Partly sunny, with a high near 84.
Thursday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 65.
Friday
A 30 percent chance of showers. Partly sunny, with a high near 85.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
4:46 am CST Feb 28, 2026
Forecast Valid:
4am CST Feb 28, 2026-6pm CST Mar 6, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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