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

89°F

32°C

Humidity 27%
Wind Speed S 14 mph
Barometer 30.00 in (1015.4 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Heat Index86°F (30°C)
Last update 20 Mar 5:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Mostly clear, with a low around 58. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 58 °F

    Mostly Clear

  • Saturday

    Saturday: Partly sunny, then gradually becoming sunny, with a high near 92. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 92 °F

    Becoming
    Sunny

  • Saturday Night

    Saturday Night: Clear, with a low around 59. South wind around 10 mph, with gusts as high as 20 mph.

    Low: 59 °F

    Clear

  • Sunday

    Sunday: Sunny, with a high near 93. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 93 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 57. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 57 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 88. South wind around 5 mph.

    High: 88 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 61. Southeast wind around 5 mph.

    Low: 61 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 89. South southwest wind 5 to 10 mph.

    High: 89 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 62. South wind 5 to 10 mph.

    Low: 62 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly clear, with a low around 58. South wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday
Partly sunny, then gradually becoming sunny, with a high near 92. South southwest wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Clear, with a low around 59. South wind around 10 mph, with gusts as high as 20 mph.
Sunday
Sunny, with a high near 93. South wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 57. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Sunny, with a high near 88. South wind around 5 mph.
Monday Night
Mostly clear, with a low around 61. Southeast wind around 5 mph.
Tuesday
Mostly sunny, with a high near 89. South southwest wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 62. South wind 5 to 10 mph.
Wednesday
Mostly sunny, with a high near 91.
Wednesday Night
Mostly clear, with a low around 61.
Thursday
Mostly sunny, with a high near 92.
Thursday Night
Mostly clear, with a low around 61.
Friday
Mostly sunny, with a high near 89.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.91°W (Elev. 597 ft)
Last Update:
5:32 pm CDT Mar 20, 2026
Forecast Valid:
6pm CDT Mar 20, 2026-6pm CDT Mar 27, 2026
 
Forecast Discussion
 
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