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

77°F

25°C

Humidity 100%
Wind Speed SE 5 mph
Barometer 29.99 in (1014.9 mb)
Dewpoint 77°F (25°C)
Visibility 9.00 mi
Heat Index78°F (26°C)
Last update 26 Jun 8:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Mostly clear, with a low around 72. Southeast wind around 5 mph becoming calm after midnight.

    Low: 72 °F

    Mostly Clear

  • Friday

    Friday: Partly sunny, then gradually becoming sunny, with a high near 93. Light south wind becoming southeast 5 to 10 mph in the morning.

    High: 93 °F

    Becoming
    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 73. South southeast wind 5 to 10 mph.

    Low: 73 °F

    Mostly Clear

  • Saturday

    Saturday: Mostly sunny, with a high near 94. Heat index values as high as 100. Light south wind becoming south southeast 5 to 10 mph in the morning.

    High: 94 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 75. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms after 1pm. Widespread haze after 1pm. Mostly sunny, with a high near 92. Light south wind becoming south southeast 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 92 °F

    Mostly Sunny
    then Slight
    Chance
    T-storms

  • Sunday Night

    Sunday Night: Widespread haze. Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 72 °F

    Haze

  • Monday

    Monday: Widespread haze. Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Haze

  • Monday Night

    Monday Night: Widespread haze. Partly cloudy, with a low around 73. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 73 °F

    Haze

Detailed Forecast

Tonight
Mostly clear, with a low around 72. Southeast wind around 5 mph becoming calm after midnight.
Friday
Partly sunny, then gradually becoming sunny, with a high near 93. Light south wind becoming southeast 5 to 10 mph in the morning.
Friday Night
Mostly clear, with a low around 73. South southeast wind 5 to 10 mph.
Saturday
Mostly sunny, with a high near 94. Heat index values as high as 100. Light south wind becoming south southeast 5 to 10 mph in the morning.
Saturday Night
Partly cloudy, with a low around 75. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Widespread haze after 1pm. Mostly sunny, with a high near 92. Light south wind becoming south southeast 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Sunday Night
Widespread haze. Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Widespread haze. Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Widespread haze. Partly cloudy, with a low around 73. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
A 20 percent chance of showers and thunderstorms after 1pm. Widespread haze. Mostly sunny, with a high near 95.
Tuesday Night
Widespread haze. Partly cloudy, with a low around 74.
Wednesday
Widespread haze. Mostly sunny, with a high near 95.
Wednesday Night
Partly cloudy, with a low around 74.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 95.
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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:
8:44 pm CDT Jun 26, 2025
Forecast Valid:
9pm CDT Jun 26, 2025-6pm CDT Jul 3, 2025
 
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Additional Resources

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