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

75°F

24°C

Humidity 100%
Wind Speed E 5 mph
Barometer 30.03 in (1016.1 mb)
Dewpoint 75°F (24°C)
Visibility 10.00 mi
Last update 13 Jul 9:56 pm CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • Tonight

    Tonight: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 74. South wind around 5 mph.

    Low: 74 °F

    Slight Chance
    T-storms

  • Monday

    Monday: A 40 percent chance of showers and thunderstorms, mainly after 4pm. Partly sunny, with a high near 92. Heat index values as high as 101. Calm wind becoming south southwest around 5 mph in the morning.

    High: 92 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Monday Night

    Monday Night: A 30 percent chance of showers and thunderstorms before 7pm. Mostly cloudy, with a low around 74. South southeast wind around 5 mph.

    Low: 74 °F

    Chance
    T-storms then
    Mostly Cloudy

  • Tuesday

    Tuesday: A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Partly sunny, with a high near 93. Heat index values as high as 102. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.

    High: 93 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Mostly Cloudy

  • Wednesday

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

    High: 94 °F

    Mostly Sunny

  • Wednesday Night

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

    Low: 73 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 94. South wind 5 to 10 mph.

    High: 94 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph.

    Low: 72 °F

    Partly Cloudy

Detailed Forecast

Tonight
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 74. South wind around 5 mph.
Monday
A 40 percent chance of showers and thunderstorms, mainly after 4pm. Partly sunny, with a high near 92. Heat index values as high as 101. Calm wind becoming south southwest around 5 mph in the morning.
Monday Night
A 30 percent chance of showers and thunderstorms before 7pm. Mostly cloudy, with a low around 74. South southeast wind around 5 mph.
Tuesday
A slight chance of showers between 1pm and 4pm, then a slight chance of showers and thunderstorms after 4pm. Partly sunny, with a high near 93. Heat index values as high as 102. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 20%.
Tuesday Night
Mostly cloudy, with a low around 74. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Partly cloudy, with a low around 73. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny, with a high near 94. South wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph.
Friday
Mostly sunny, with a high near 94.
Friday Night
Partly cloudy, with a low around 74.
Saturday
Mostly sunny, with a high near 94.
Saturday Night
Partly cloudy, with a low around 75.
Sunday
Mostly sunny, with a high near 95.
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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:
9:26 pm CDT Jul 13, 2025
Forecast Valid:
10pm CDT Jul 13, 2025-6pm CDT Jul 20, 2025
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation