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.

A Few Clouds

93°F

34°C

Humidity 52%
Wind Speed S 10 mph
Barometer 30.04 in (1016.4 mb)
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index102°F (39°C)
Last update 20 Jun 1:56 pm CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • This Afternoon

    This Afternoon: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 93. Heat index values as high as 103. South wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 93 °F

    Slight Chance
    T-storms

  • Tonight

    Tonight: Partly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 94. Heat index values as high as 100. South wind 5 to 10 mph increasing to 10 to 15 mph in the afternoon. Winds could gust as high as 25 mph.

    High: 94 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 75 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 95. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 72. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 72 °F

    Mostly Clear

  • Monday

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

    High: 94 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 71. Southeast wind 10 to 15 mph becoming light south southeast after midnight. Winds could gust as high as 20 mph.

    Low: 71 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 93. Light east southeast wind increasing to 5 to 10 mph in the morning.

    High: 93 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 93. Heat index values as high as 103. South wind 10 to 15 mph, with gusts as high as 20 mph.
Tonight
Partly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Mostly sunny, with a high near 94. Heat index values as high as 100. South wind 5 to 10 mph increasing to 10 to 15 mph in the afternoon. Winds could gust as high as 25 mph.
Saturday Night
Partly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday
Mostly sunny, with a high near 95. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Mostly clear, with a low around 72. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 94. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly clear, with a low around 71. Southeast wind 10 to 15 mph becoming light south southeast after midnight. Winds could gust as high as 20 mph.
Tuesday
Mostly sunny, with a high near 93. Light east southeast wind increasing to 5 to 10 mph in the morning.
Tuesday Night
Partly cloudy, with a low around 71.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 93.
Wednesday Night
Partly cloudy, with a low around 72.
Thursday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 92.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
1:48 pm CDT Jun 20, 2025
Forecast Valid:
2pm CDT Jun 20, 2025-6pm CDT Jun 26, 2025
 
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