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.

Mostly Cloudy

90°F

32°C

Humidity 38%
Wind Speed SE 14 mph
Barometer 30.01 in (1015.4 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Heat Index90°F (32°C)
Last update 25 Mar 3:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Increasing clouds, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 65 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Cloudy through mid morning, then gradual clearing, with a high near 88. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 88 °F

    Becoming
    Sunny

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 62. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 62 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, then gradually becoming sunny, with a high near 89. South wind 5 to 10 mph becoming east in the afternoon.

    High: 89 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Partly cloudy, with a low around 59. North northeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 59 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 80. North northeast wind around 10 mph, with gusts as high as 20 mph.

    High: 80 °F

    Partly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 56. East northeast wind 5 to 10 mph becoming light and variable after midnight.

    Low: 56 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 85. Light south southeast wind becoming south 5 to 10 mph in the morning.

    High: 85 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 59. South southeast wind 5 to 10 mph.

    Low: 59 °F

    Partly Cloudy

Detailed Forecast

Tonight
Increasing clouds, with a low around 65. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday
Cloudy through mid morning, then gradual clearing, with a high near 88. South wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday Night
Increasing clouds, with a low around 62. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
Mostly cloudy, then gradually becoming sunny, with a high near 89. South wind 5 to 10 mph becoming east in the afternoon.
Friday Night
Partly cloudy, with a low around 59. North northeast wind around 10 mph, with gusts as high as 20 mph.
Saturday
Partly sunny, with a high near 80. North northeast wind around 10 mph, with gusts as high as 20 mph.
Saturday Night
Mostly clear, with a low around 56. East northeast wind 5 to 10 mph becoming light and variable after midnight.
Sunday
Mostly sunny, with a high near 85. Light south southeast wind becoming south 5 to 10 mph in the morning.
Sunday Night
Partly cloudy, with a low around 59. South southeast wind 5 to 10 mph.
Monday
Partly sunny, with a high near 88.
Monday Night
Mostly cloudy, with a low around 63.
Tuesday
Partly sunny, with a high near 90.
Tuesday Night
Mostly cloudy, with a low around 65.
Wednesday
Partly sunny, with a high near 90.
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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:
2:50 pm CDT Mar 25, 2026
Forecast Valid:
4pm CDT Mar 25, 2026-6pm CDT Apr 1, 2026
 
Forecast Discussion
 
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