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

87°F

31°C

Humidity 65%
Wind Speed Vrbl 3 mph
Barometer 30.07 in (1017.4 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index95°F (35°C)
Last update 23 Sep 9:56 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 103. East wind around 5 mph.

    High: 97 °F

    Mostly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 74. East southeast wind around 5 mph becoming calm in the evening.

    Low: 74 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 96. Heat index values as high as 102. Calm wind becoming east around 5 mph in the afternoon.

    High: 96 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 74. East wind around 5 mph becoming calm in the evening.

    Low: 74 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 96. Calm wind becoming east around 5 mph in the afternoon.

    High: 96 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 73. East wind around 5 mph becoming calm in the evening.

    Low: 73 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 96. Calm wind becoming south around 5 mph.

    High: 96 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 73. Southeast wind around 5 mph.

    Low: 73 °F

    Mostly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 96. Calm wind becoming south around 5 mph.

    High: 96 °F

    Mostly Sunny

Detailed Forecast

Today
Mostly sunny, with a high near 97. Heat index values as high as 103. East wind around 5 mph.
Tonight
Mostly cloudy, with a low around 74. East southeast wind around 5 mph becoming calm in the evening.
Thursday
Mostly sunny, with a high near 96. Heat index values as high as 102. Calm wind becoming east around 5 mph in the afternoon.
Thursday Night
Mostly cloudy, with a low around 74. East wind around 5 mph becoming calm in the evening.
Friday
Mostly sunny, with a high near 96. Calm wind becoming east around 5 mph in the afternoon.
Friday Night
Partly cloudy, with a low around 73. East wind around 5 mph becoming calm in the evening.
Saturday
Partly sunny, with a high near 96. Calm wind becoming south around 5 mph.
Saturday Night
Mostly cloudy, with a low around 73. Southeast wind around 5 mph.
Sunday
Mostly sunny, with a high near 96. Calm wind becoming south around 5 mph.
Sunday Night
Partly cloudy, with a low around 73.
Monday
Mostly sunny, with a high near 96.
Monday Night
A 20 percent chance of showers. Partly cloudy, with a low around 74.
Tuesday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 95.
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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 23, 2026
Forecast Valid:
10am CDT Sep 23, 2026-6pm CDT Sep 29, 2026
 
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Additional Resources

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