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.

Fair

81°F

27°C

Humidity 74%
Wind Speed S 10 mph
Barometer 30.05 in (1016.9 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index85°F (29°C)
Last update 24 Jul 10:56 pm CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • Tonight

    Tonight: Partly cloudy, with a low around 75. South wind 5 to 10 mph.

    Low: 75 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 94. South wind around 5 mph.

    High: 94 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 73. South wind 5 to 10 mph.

    Low: 73 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 95. Heat index values as high as 102. South southwest wind around 5 mph.

    High: 95 °F

    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 74. South wind around 5 mph.

    Low: 74 °F

    Clear

  • Monday

    Monday: Sunny, with a high near 97. South wind 5 to 10 mph.

    High: 97 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 99. South wind 5 to 10 mph.

    High: 99 °F

    Hot

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Mostly Clear

Detailed Forecast

Tonight
Partly cloudy, with a low around 75. South wind 5 to 10 mph.
Saturday
Mostly sunny, with a high near 94. South wind around 5 mph.
Saturday Night
Partly cloudy, with a low around 73. South wind 5 to 10 mph.
Sunday
Sunny, with a high near 95. Heat index values as high as 102. South southwest wind around 5 mph.
Sunday Night
Clear, with a low around 74. South wind around 5 mph.
Monday
Sunny, with a high near 97. South wind 5 to 10 mph.
Monday Night
Mostly clear, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Sunny and hot, with a high near 99. South wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Sunny and hot, with a high near 99.
Wednesday Night
Mostly clear, with a low around 76.
Thursday
Mostly sunny and hot, with a high near 100.
Thursday Night
Mostly clear, with a low around 77.
Friday
Mostly sunny and hot, with a high near 100.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
11:32 pm CDT Jul 24, 2026
Forecast Valid:
11pm CDT Jul 24, 2026-6pm CDT Jul 31, 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