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.

Partly Cloudy

83°F

28°C

Humidity 65%
Wind Speed S 15 mph
Barometer 30.12 in (1019.2 mb)
Dewpoint 70°F (21°C)
Visibility 10.00 mi
Heat Index87°F (31°C)
Last update 11 Oct 10:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly sunny, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 69. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.

    Low: 69 °F

    Partly Cloudy

  • Columbus Day

    Columbus Day: A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.

    High: 91 °F

    Chance
    Showers

  • Monday Night

    Monday Night: A 10 percent chance of showers before 7pm. Mostly cloudy, with a low around 75. Southeast wind around 5 mph.

    Low: 75 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 93 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 75. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Wednesday

    Wednesday: A 30 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 92. South southeast wind around 10 mph, with gusts as high as 20 mph.

    High: 92 °F

    Mostly Cloudy
    then Chance
    Showers

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.

    Low: 72 °F

    Partly Cloudy
    then Slight
    Chance
    T-storms

  • Thursday

    Thursday: A 20 percent chance of showers. Partly sunny, with a high near 89. South southeast wind 5 to 10 mph.

    High: 89 °F

    Slight Chance
    Showers

Detailed Forecast

Today
Mostly sunny, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tonight
Partly cloudy, with a low around 69. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.
Columbus Day
A slight chance of showers, then a chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 30%.
Monday Night
A 10 percent chance of showers before 7pm. Mostly cloudy, with a low around 75. Southeast wind around 5 mph.
Tuesday
Partly sunny, with a high near 93. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 75. South southeast wind around 10 mph, with gusts as high as 20 mph.
Wednesday
A 30 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 92. South southeast wind around 10 mph, with gusts as high as 20 mph.
Wednesday Night
A 20 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 25 mph.
Thursday
A 20 percent chance of showers. Partly sunny, with a high near 89. South southeast wind 5 to 10 mph.
Thursday Night
A 20 percent chance of showers. Mostly clear, with a low around 68.
Friday
A 20 percent chance of showers. Partly sunny, with a high near 81.
Friday Night
Mostly cloudy, with a low around 61.
Saturday
Mostly sunny, with a high near 74.
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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:
11:32 am CDT Oct 11, 2026
Forecast Valid:
11am CDT Oct 11, 2026-6pm CDT Oct 17, 2026
 
Forecast Discussion
 
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Additional Resources

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Chance of Precipitation