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

84°F

29°C

Humidity 55%
Wind Speed S 14 mph
Barometer 29.94 in (1013.0 mb)
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Heat Index86°F (30°C)
Last update 15 Apr 2:56 pm CDT
Extended Forecast for

4 Miles WNW San Marcos TX

  • This Afternoon

    This Afternoon: A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82. South wind around 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 7pm. Increasing clouds, with a low around 67. South southeast wind 5 to 10 mph.

    Low: 67 °F

    Chance
    T-storms then
    Mostly Cloudy

  • Thursday

    Thursday: Cloudy, then gradually becoming mostly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 87 °F

    Decreasing
    Clouds

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 67 °F

    Increasing
    Clouds

  • Friday

    Friday: Partly sunny, with a high near 88. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 88 °F

    Partly Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 66. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 66 °F

    Mostly Cloudy

  • Saturday

    Saturday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 76. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 60%.

    High: 76 °F

    Chance
    T-storms then
    Showers
    Likely

  • Saturday Night

    Saturday Night: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 53. North northeast wind around 15 mph, with gusts as high as 25 mph.

    Low: 53 °F

    Chance
    T-storms

  • Sunday

    Sunday: A 20 percent chance of showers. Mostly cloudy, with a high near 69. Northeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 69 °F

    Slight Chance
    Showers

Detailed Forecast

This Afternoon
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 82. South wind around 10 mph, with gusts as high as 20 mph.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 7pm. Increasing clouds, with a low around 67. South southeast wind 5 to 10 mph.
Thursday
Cloudy, then gradually becoming mostly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Increasing clouds, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.
Friday
Partly sunny, with a high near 88. South wind 10 to 15 mph, with gusts as high as 30 mph.
Friday Night
Mostly cloudy, with a low around 66. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 76. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 60%.
Saturday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 53. North northeast wind around 15 mph, with gusts as high as 25 mph.
Sunday
A 20 percent chance of showers. Mostly cloudy, with a high near 69. Northeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
A slight chance of showers, then a chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 55. Chance of precipitation is 30%.
Monday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 63.
Monday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 56.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 73.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
4 Miles WNW San Marcos TX
 29.9°N 97.99°W (Elev. 850 ft)
Last Update:
2:48 pm CDT Apr 15, 2026
Forecast Valid:
3pm CDT Apr 15, 2026-6pm CDT Apr 21, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation