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.

A Few Clouds

79°F

26°C

Humidity 85%
Wind Speed SE 5 mph
Barometer 30.07 in (1017.4 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 23 Sep 9:56 pm CDT
Extended Forecast for

4 Miles SSW San Marcos TX

  • Tonight

    Tonight: Mostly cloudy, with a low around 74. East southeast wind around 5 mph becoming calm after midnight.

    Low: 74 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 97. Heat index values as high as 104. Calm wind becoming east around 5 mph in the morning.

    High: 97 °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 74. Southeast wind around 5 mph.

    Low: 74 °F

    Mostly Cloudy

  • Sunday

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

    High: 96 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 74. Southeast wind around 5 mph.

    Low: 74 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 74. East southeast wind around 5 mph becoming calm after midnight.
Thursday
Mostly sunny, with a high near 97. Heat index values as high as 104. Calm wind becoming east around 5 mph in the morning.
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 74. Southeast wind around 5 mph.
Sunday
Mostly sunny, with a high near 96. Calm wind becoming south southwest around 5 mph.
Sunday Night
Partly cloudy, with a low around 74. Southeast wind around 5 mph.
Monday
Mostly sunny, with a high near 95.
Monday Night
Partly cloudy, with a low around 74.
Tuesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 94.
Tuesday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72.
Wednesday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 88.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles SSW San Marcos TX
 29.83°N 97.94°W (Elev. 610 ft)
Last Update:
9:44 pm CDT Sep 23, 2026
Forecast Valid:
10pm CDT Sep 23, 2026-6pm CDT Sep 30, 2026
 
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Additional Resources

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