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

70°F

21°C

Humidity 79%
Wind Speed S 14 mph
Barometer 30.08 in (1017.8 mb)
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 31 Mar 12:56 am CDT
Extended Forecast for

4 Miles WNW San Marcos TX

  • Overnight

    Overnight: Mostly cloudy, with a low around 64. South wind around 10 mph, with gusts as high as 20 mph.

    Low: 64 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Cloudy through mid morning, then gradual clearing, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 87 °F

    Gradual
    Clearing

  • Tuesday Night

    Tuesday Night: Increasing clouds, with a low around 66. South wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 66 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Cloudy, then gradually becoming mostly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 90 °F

    Decreasing
    Clouds

  • Wednesday Night

    Wednesday Night: A 30 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    Low: 67 °F

    Partly Cloudy
    then Chance
    T-storms

  • Thursday

    Thursday: Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 85. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    High: 85 °F

    Showers
    Likely

  • Thursday Night

    Thursday Night: A slight chance of thunderstorms before 7pm. Mostly cloudy, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 10%.

    Low: 67 °F

    Slight Chance
    T-storms then
    Mostly Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 87. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 87 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: A slight chance of showers, with thunderstorms also possible after 1am. Mostly cloudy, with a low around 67. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.

    Low: 67 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

Detailed Forecast

Overnight
Mostly cloudy, with a low around 64. South wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Cloudy through mid morning, then gradual clearing, with a high near 87. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Increasing clouds, with a low around 66. South wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
Cloudy, then gradually becoming mostly sunny, with a high near 90. South wind 10 to 15 mph, with gusts as high as 30 mph.
Wednesday Night
A 30 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 67. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Thursday
Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 85. South southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Thursday Night
A slight chance of thunderstorms before 7pm. Mostly cloudy, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph. Chance of precipitation is 10%.
Friday
Mostly cloudy, with a high near 87. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Friday Night
A slight chance of showers, with thunderstorms also possible after 1am. Mostly cloudy, with a low around 67. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 20%.
Saturday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Cloudy, with a high near 80. Chance of precipitation is 60%.
Saturday Night
A 50 percent chance of showers and thunderstorms. Cloudy, with a low around 51.
Sunday
A 40 percent chance of showers. Mostly cloudy, with a high near 66.
Sunday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 47.
Monday
A 20 percent chance of showers. Mostly sunny, with a high near 70.
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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:
1:28 am CDT Mar 31, 2026
Forecast Valid:
1am CDT Mar 31, 2026-6pm CDT Apr 6, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation