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.

Overcast

85°F

29°C

Humidity 70%
Wind Speed SE 8 mph
Barometer 29.93 in (1012.7 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index93°F (34°C)
Last update 12 Oct 7:56 pm CDT
Extended Forecast for

3 Miles SE San Marcos TX

  • Tonight

    Tonight: Mostly cloudy, with a low around 76. South wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, then gradually becoming sunny, with a high near 95. Heat index values as high as 103. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Decreasing
    Clouds

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 76. South southeast wind around 10 mph, with gusts as high as 25 mph.

    Low: 76 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 93. Heat index values as high as 102. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 93 °F

    Slight Chance
    T-storms then
    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 69. South southeast wind 5 to 15 mph, with gusts as high as 30 mph.

    Low: 69 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 91. South southeast wind around 5 mph.

    High: 91 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 65. East southeast wind around 5 mph becoming calm in the evening.

    Low: 65 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 83. Breezy, with a north northeast wind 20 to 25 mph, with gusts as high as 35 mph.

    High: 83 °F

    Mostly Sunny
    then Mostly
    Sunny and
    Breezy

  • Friday Night

    Friday Night: Partly cloudy, with a low around 59. North wind 15 to 20 mph, with gusts as high as 40 mph.

    Low: 59 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 76. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly cloudy, then gradually becoming sunny, with a high near 95. Heat index values as high as 103. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Increasing clouds, with a low around 76. South southeast wind around 10 mph, with gusts as high as 25 mph.
Wednesday
A 40 percent chance of showers and thunderstorms, mainly after 1pm. Partly sunny, with a high near 93. Heat index values as high as 102. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
Partly cloudy, with a low around 69. South southeast wind 5 to 15 mph, with gusts as high as 30 mph.
Thursday
Mostly sunny, with a high near 91. South southeast wind around 5 mph.
Thursday Night
Mostly clear, with a low around 65. East southeast wind around 5 mph becoming calm in the evening.
Friday
Mostly sunny, with a high near 83. Breezy, with a north northeast wind 20 to 25 mph, with gusts as high as 35 mph.
Friday Night
Partly cloudy, with a low around 59. North wind 15 to 20 mph, with gusts as high as 40 mph.
Saturday
Mostly sunny, with a high near 78.
Saturday Night
Mostly clear, with a low around 56.
Sunday
Sunny, with a high near 81.
Sunday Night
Partly cloudy, with a low around 59.
Monday
A 20 percent chance of showers. Mostly sunny, with a high near 85.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles SE San Marcos TX
 29.86°N 97.91°W (Elev. 630 ft)
Last Update:
6:44 pm CDT Oct 12, 2026
Forecast Valid:
8pm CDT Oct 12, 2026-6pm CDT Oct 19, 2026
 
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Additional Resources

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