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

80°F

27°C

Humidity 24%
Wind Speed S 13 G 21 mph
Barometer 29.96 in (1014.1 mb)
Dewpoint 40°F (4°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 13 Mar 3:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Mostly clear, with a low around 51. South wind 5 to 10 mph.

    Low: 51 °F

    Mostly Clear

  • Saturday

    Saturday: Partly sunny, then gradually becoming sunny, with a high near 85. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 85 °F

    Becoming
    Sunny

  • Saturday Night

    Saturday Night: Increasing clouds, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Cloudy, then gradually becoming mostly sunny, with a high near 92. South wind 10 to 15 mph becoming west in the afternoon. Winds could gust as high as 25 mph.

    High: 92 °F

    Decreasing
    Clouds

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 39. Breezy, with a north wind 15 to 25 mph, with gusts as high as 40 mph.

    Low: 39 °F

    Mostly Clear
    and Breezy

  • Monday

    Monday: Mostly sunny, with a high near 58. North wind 10 to 20 mph, with gusts as high as 30 mph.

    High: 58 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 36. North northeast wind 5 to 10 mph becoming light and variable in the evening.

    Low: 36 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Sunny, with a high near 68. Light south southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 68 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 45. South wind 5 to 10 mph.

    Low: 45 °F

    Mostly Clear

Detailed Forecast

Tonight
Mostly clear, with a low around 51. South wind 5 to 10 mph.
Saturday
Partly sunny, then gradually becoming sunny, with a high near 85. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Saturday Night
Increasing clouds, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Sunday
Cloudy, then gradually becoming mostly sunny, with a high near 92. South wind 10 to 15 mph becoming west in the afternoon. Winds could gust as high as 25 mph.
Sunday Night
Mostly clear, with a low around 39. Breezy, with a north wind 15 to 25 mph, with gusts as high as 40 mph.
Monday
Mostly sunny, with a high near 58. North wind 10 to 20 mph, with gusts as high as 30 mph.
Monday Night
Mostly cloudy, with a low around 36. North northeast wind 5 to 10 mph becoming light and variable in the evening.
Tuesday
Sunny, with a high near 68. Light south southeast wind becoming south 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Tuesday Night
Mostly clear, with a low around 45. South wind 5 to 10 mph.
Wednesday
Sunny, with a high near 78.
Wednesday Night
Mostly clear, with a low around 52.
Thursday
Sunny, with a high near 84.
Thursday Night
Clear, with a low around 55.
Friday
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:
2:46 pm CDT Mar 13, 2026
Forecast Valid:
4pm CDT Mar 13, 2026-6pm CDT Mar 20, 2026
 
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Additional Resources

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