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

21°C

70°F

Humidity 100%
Wind Speed S 6 km/h
Barometer 1004.6 mb (29.69 in)
Dewpoint 21°C (70°F)
Visibility 16 km
Last update 15 May 3:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Partly sunny and hot, with a high near 37. South wind 10 to 15 km/h, with gusts as high as 30 km/h.

    High: 37 °C

    Hot

  • Tonight

    Tonight: Mostly cloudy, with a low around 23. Southeast wind around 15 km/h, with gusts as high as 30 km/h.

    Low: 23 °C

    Mostly Cloudy

  • Friday

    Friday: Cloudy, then gradually becoming mostly sunny and hot, with a high near 38. Heat index values as high as 41. South wind 15 to 20 km/h, with gusts as high as 35 km/h.

    High: 38 °C

    Hot

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 24. South southeast wind 10 to 15 km/h.

    Low: 24 °C

    Mostly Cloudy

  • Saturday

    Saturday: Partly sunny and hot, with a high near 37. South wind 10 to 20 km/h, with gusts as high as 35 km/h.

    High: 37 °C

    Hot

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 24. South southeast wind 15 to 20 km/h, with gusts as high as 35 km/h.

    Low: 24 °C

    Mostly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 36. South southeast wind 15 to 20 km/h increasing to 20 to 25 km/h in the afternoon. Winds could gust as high as 45 km/h.

    High: 36 °C

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 24. South southeast wind 20 to 25 km/h decreasing to 15 to 20 km/h after midnight. Winds could gust as high as 45 km/h.

    Low: 24 °C

    Mostly Cloudy

  • Monday

    Monday: Partly sunny, with a high near 36. South southeast wind 15 to 20 km/h increasing to 25 to 30 km/h in the afternoon. Winds could gust as high as 45 km/h.

    High: 36 °C

    Partly Sunny

Detailed Forecast

Today
Partly sunny and hot, with a high near 37. South wind 10 to 15 km/h, with gusts as high as 30 km/h.
Tonight
Mostly cloudy, with a low around 23. Southeast wind around 15 km/h, with gusts as high as 30 km/h.
Friday
Cloudy, then gradually becoming mostly sunny and hot, with a high near 38. Heat index values as high as 41. South wind 15 to 20 km/h, with gusts as high as 35 km/h.
Friday Night
Mostly cloudy, with a low around 24. South southeast wind 10 to 15 km/h.
Saturday
Partly sunny and hot, with a high near 37. South wind 10 to 20 km/h, with gusts as high as 35 km/h.
Saturday Night
Mostly cloudy, with a low around 24. South southeast wind 15 to 20 km/h, with gusts as high as 35 km/h.
Sunday
Partly sunny, with a high near 36. South southeast wind 15 to 20 km/h increasing to 20 to 25 km/h in the afternoon. Winds could gust as high as 45 km/h.
Sunday Night
Mostly cloudy, with a low around 24. South southeast wind 20 to 25 km/h decreasing to 15 to 20 km/h after midnight. Winds could gust as high as 45 km/h.
Monday
Partly sunny, with a high near 36. South southeast wind 15 to 20 km/h increasing to 25 to 30 km/h in the afternoon. Winds could gust as high as 45 km/h.
Monday Night
Mostly cloudy, with a low around 24.
Tuesday
Scattered showers and thunderstorms. Partly sunny, with a high near 34. Chance of precipitation is 30%.
Tuesday Night
Partly cloudy, with a low around 22.
Wednesday
Mostly sunny, with a high near 36.
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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 m)
Last Update:
3:44 am CDT May 15, 2025
Forecast Valid:
4am CDT May 15, 2025-6pm CDT May 21, 2025
 
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Additional Resources

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