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 and Breezy

86°F

30°C

Humidity 30%
Wind Speed S 23 G 26 mph
Barometer 29.95 in (1013.5 mb)
Dewpoint 51°F (11°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 22 Mar 12:56 pm CDT
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 91. South wind around 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Sunny

  • 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

  • Monday

    Monday: Sunny, with a high near 87. Calm wind becoming south southeast around 5 mph in the afternoon.

    High: 87 °F

    Sunny

  • Monday Night

    Monday Night: Partly cloudy, with a low around 60. Southeast wind around 5 mph.

    Low: 60 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Mostly sunny, with a high near 87. South wind 5 to 10 mph.

    High: 87 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 63. South southeast wind 5 to 10 mph.

    Low: 63 °F

    Mostly Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 90 °F

    Mostly Sunny

  • Wednesday Night

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

    Low: 63 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 91. South wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 91 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 91. South wind around 15 mph, with gusts as high as 25 mph.
Tonight
Mostly clear, with a low around 58. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Sunny, with a high near 87. Calm wind becoming south southeast around 5 mph in the afternoon.
Monday Night
Partly cloudy, with a low around 60. Southeast wind around 5 mph.
Tuesday
Mostly sunny, with a high near 87. South wind 5 to 10 mph.
Tuesday Night
Mostly clear, with a low around 63. South southeast wind 5 to 10 mph.
Wednesday
Mostly sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Mostly clear, 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 91. South wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday Night
Mostly clear, with a low around 63.
Friday
Mostly sunny, with a high near 89.
Friday Night
Partly cloudy, with a low around 58.
Saturday
Partly sunny, with a high near 79.
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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:
12:44 pm CDT Mar 22, 2026
Forecast Valid:
1pm CDT Mar 22, 2026-6pm CDT Mar 28, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation