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.

Overcast

69°F

21°C

Humidity 76%
Wind Speed S 10 mph
Barometer 30.03 in (1016.3 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 27 Mar 7:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly cloudy through mid morning, then gradual clearing, with a high near 87. South wind 5 to 10 mph becoming east in the afternoon. Winds could gust as high as 20 mph.

    High: 87 °F

    Becoming
    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 56. North wind 15 to 20 mph, with gusts as high as 35 mph.

    Low: 56 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Cloudy, then gradually becoming mostly sunny, with a high near 70. North northeast wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 70 °F

    Decreasing
    Clouds

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 56. Northeast wind around 5 mph becoming south after midnight.

    Low: 56 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly 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

    Partly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 62. South wind around 10 mph.

    Low: 62 °F

    Partly Cloudy

  • Monday

    Monday: Partly sunny, with a high near 89. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 89 °F

    Partly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 63 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 90 °F

    Partly Sunny

Detailed Forecast

Today
Mostly cloudy through mid morning, then gradual clearing, with a high near 87. South wind 5 to 10 mph becoming east in the afternoon. Winds could gust as high as 20 mph.
Tonight
Increasing clouds, with a low around 56. North wind 15 to 20 mph, with gusts as high as 35 mph.
Saturday
Cloudy, then gradually becoming mostly sunny, with a high near 70. North northeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday Night
Partly cloudy, with a low around 56. Northeast wind around 5 mph becoming south after midnight.
Sunday
Partly 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.
Sunday Night
Partly cloudy, with a low around 62. South wind around 10 mph.
Monday
Partly sunny, with a high near 89. South wind 5 to 15 mph, with gusts as high as 25 mph.
Monday Night
Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday
Partly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Mostly cloudy, with a low around 66.
Wednesday
Partly sunny, with a high near 91.
Wednesday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 64.
Thursday
A 20 percent chance of showers and thunderstorms. Partly sunny, with a high near 87.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
6:46 am CDT Mar 27, 2026
Forecast Valid:
8am CDT Mar 27, 2026-6pm CDT Apr 2, 2026
 
Forecast Discussion
 
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Additional Resources

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