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

65°F

18°C

Humidity 73%
Wind Speed S 6 mph
Barometer 30.10 in (1018.7 mb)
Dewpoint 56°F (13°C)
Visibility 10.00 mi
Last update 24 Mar 1:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Clear early, then becoming mostly cloudy, with a low around 60. South southwest wind around 5 mph.

    Low: 60 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Patchy fog before 10am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 87. Light south southwest wind becoming south 5 to 10 mph in the morning.

    High: 87 °F

    Patchy Fog
    then Sunny

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 64. South southeast wind 5 to 10 mph.

    Low: 64 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 89. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 89 °F

    Patchy Fog
    then Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Partly Cloudy

  • Thursday

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

    High: 90 °F

    Mostly Sunny

  • Thursday Night

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

    Low: 62 °F

    Mostly Clear

  • Friday

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

    High: 89 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 59. East wind around 10 mph becoming north northeast after midnight.

    Low: 59 °F

    Mostly Clear

Detailed Forecast

Overnight
Clear early, then becoming mostly cloudy, with a low around 60. South southwest wind around 5 mph.
Tuesday
Patchy fog before 10am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 87. Light south southwest wind becoming south 5 to 10 mph in the morning.
Tuesday Night
Increasing clouds, with a low around 64. South southeast wind 5 to 10 mph.
Wednesday
Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 89. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Partly cloudy, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday Night
Mostly clear, with a low around 62. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
Mostly sunny, with a high near 89. South wind 5 to 10 mph.
Friday Night
Mostly clear, with a low around 59. East wind around 10 mph becoming north northeast after midnight.
Saturday
Mostly sunny, with a high near 80.
Saturday Night
Mostly clear, with a low around 54.
Sunday
Sunny, with a high near 85.
Sunday Night
Partly cloudy, with a low around 58.
Monday
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:
2:42 am CDT Mar 24, 2026
Forecast Valid:
2am CDT Mar 24, 2026-6pm CDT Mar 30, 2026
 
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Additional Resources

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