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 with Haze

92°F

33°C

Humidity 51%
Wind Speed S 10 mph
Barometer 30.07 in (1017.3 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Heat Index99°F (37°C)
Last update 26 Jul 12:56 pm CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 96. Heat index values as high as 102. South wind around 5 mph.

    High: 96 °F

    Sunny

  • Tonight

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

    Low: 75 °F

    Mostly Clear

  • Monday

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

    High: 97 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 98. South wind 5 to 10 mph.

    High: 98 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny and hot, with a high near 100. South southwest wind around 5 mph.

    High: 100 °F

    Hot

Detailed Forecast

This Afternoon
Sunny, with a high near 96. Heat index values as high as 102. South wind around 5 mph.
Tonight
Mostly clear, with a low around 75. South wind 5 to 10 mph.
Monday
Sunny, with a high near 97. Heat index values as high as 104. 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
Mostly sunny, with a high near 97. South wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Mostly sunny, with a high near 98. South wind 5 to 10 mph.
Wednesday Night
Mostly clear, with a low around 76. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny and hot, with a high near 100. South southwest wind around 5 mph.
Thursday Night
Mostly clear, with a low around 76.
Friday
Mostly sunny and hot, with a high near 100.
Friday Night
Mostly clear, with a low around 78.
Saturday
Mostly sunny and hot, with a high near 101.
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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:
1:24 pm CDT Jul 26, 2026
Forecast Valid:
1pm CDT Jul 26, 2026-6pm CDT Aug 1, 2026
 
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