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

83°F

28°C

Humidity 82%
Wind Speed S 7 mph
Barometer 30.14 in (1019.8 mb)
Dewpoint 77°F (25°C)
Visibility 10.00 mi
Heat Index92°F (33°C)
Last update 9 Sep 8:56 am CDT
Extended Forecast for

3 Miles WSW San Marcos TX

  • Today

    Today: Mostly sunny, with a high near 97. Heat index values as high as 104. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 97 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 75. Southeast wind 5 to 10 mph becoming light south after midnight.

    Low: 75 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 97. Heat index values as high as 103. Calm wind becoming south southeast around 5 mph in the afternoon.

    High: 97 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 75. Southeast wind around 5 mph.

    Low: 75 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 98. Light south southwest wind becoming south 5 to 10 mph in the afternoon.

    High: 98 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 76. South wind 5 to 10 mph.

    Low: 76 °F

    Partly Cloudy

  • Saturday

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

    High: 99 °F

    Hot

  • Saturday Night

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

    Low: 76 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 98. South wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 98 °F

    Mostly Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 97. Heat index values as high as 104. Calm wind becoming southeast around 5 mph in the afternoon.
Tonight
Partly cloudy, with a low around 75. Southeast wind 5 to 10 mph becoming light south after midnight.
Thursday
Mostly sunny, with a high near 97. Heat index values as high as 103. Calm wind becoming south southeast around 5 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 75. Southeast wind around 5 mph.
Friday
Mostly sunny, with a high near 98. Light south southwest wind becoming south 5 to 10 mph in the afternoon.
Friday Night
Partly cloudy, with a low around 76. South wind 5 to 10 mph.
Saturday
Sunny and hot, with a high near 99. South wind 5 to 10 mph.
Saturday Night
Mostly clear, with a low around 76. South southeast wind around 10 mph, with gusts as high as 20 mph.
Sunday
Mostly sunny, with a high near 98. South wind 5 to 15 mph, with gusts as high as 20 mph.
Sunday Night
Partly cloudy, with a low around 76.
Monday
Mostly sunny, with a high near 98.
Monday Night
Mostly clear, with a low around 75.
Tuesday
Partly sunny, with a high near 98.
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ABOUT THIS FORECAST

 
Point Forecast:
3 Miles WSW San Marcos TX
 29.86°N 97.97°W (Elev. 646 ft)
Last Update:
6:42 am CDT Sep 9, 2026
Forecast Valid:
9am CDT Sep 9, 2026-6pm CDT Sep 15, 2026
 
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Additional Resources

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