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

77°F

25°C

Humidity 90%
Wind Speed S 6 mph
Barometer 30.08 in (1017.7 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index78°F (26°C)
Last update 25 Jul 1:56 am CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • Overnight

    Overnight: Partly cloudy, with a low around 75. South wind around 5 mph.

    Low: 75 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 96. Heat index values as high as 101. South southwest wind 5 to 10 mph.

    High: 96 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 74. South southeast wind 5 to 10 mph.

    Low: 74 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 97. Heat index values as high as 104. South southwest wind 5 to 10 mph.

    High: 97 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 75. South southeast wind 5 to 10 mph.

    Low: 75 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 98. South wind 5 to 10 mph.

    High: 98 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 75. South wind 5 to 10 mph.

    Low: 75 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 98. South wind 5 to 10 mph.

    High: 98 °F

    Sunny

  • Tuesday Night

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

    Low: 75 °F

    Mostly Clear

Detailed Forecast

Overnight
Partly cloudy, with a low around 75. South wind around 5 mph.
Saturday
Mostly sunny, with a high near 96. Heat index values as high as 101. South southwest wind 5 to 10 mph.
Saturday Night
Partly cloudy, with a low around 74. South southeast wind 5 to 10 mph.
Sunday
Mostly sunny, with a high near 97. Heat index values as high as 104. South southwest wind 5 to 10 mph.
Sunday Night
Mostly clear, with a low around 75. South southeast wind 5 to 10 mph.
Monday
Sunny, with a high near 98. South wind 5 to 10 mph.
Monday Night
Mostly clear, with a low around 75. South wind 5 to 10 mph.
Tuesday
Sunny, with a high near 98. South wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 75. South southeast wind 5 to 10 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 99.
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
1:30 am CDT Jul 25, 2026
Forecast Valid:
2am CDT Jul 25, 2026-6pm CDT Jul 31, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation