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

73°F

23°C

Humidity 81%
Wind Speed S 13 mph
Barometer 29.91 in (1012.0 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 3 Apr 12:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Cloudy, with a low around 69. South wind around 10 mph.

    Low: 69 °F

    Cloudy

  • Friday

    Friday: Mostly cloudy, with a high near 88. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.

    High: 88 °F

    Mostly Cloudy

  • Friday Night

    Friday Night: A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 68. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    Low: 68 °F

    Chance
    Showers

  • Saturday

    Saturday: Showers and possibly a thunderstorm. High near 79. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.

    High: 79 °F

    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 53. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    Low: 53 °F

    Chance
    Showers

  • Sunday

    Sunday: A 30 percent chance of showers. Mostly cloudy, with a high near 66. North northeast wind around 15 mph, with gusts as high as 25 mph.

    High: 66 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: A 20 percent chance of showers. Cloudy, with a low around 52. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 52 °F

    Slight Chance
    Showers

  • Monday

    Monday: Mostly cloudy, with a high near 68. Northeast wind 5 to 10 mph.

    High: 68 °F

    Mostly Cloudy

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 49. Northeast wind around 5 mph becoming calm in the evening.

    Low: 49 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Cloudy, with a low around 69. South wind around 10 mph.
Friday
Mostly cloudy, with a high near 88. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.
Friday Night
A slight chance of showers, then a chance of showers and thunderstorms after 10pm. Mostly cloudy, with a low around 68. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.
Saturday
Showers and possibly a thunderstorm. High near 79. South southeast wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 53. North northeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.
Sunday
A 30 percent chance of showers. Mostly cloudy, with a high near 66. North northeast wind around 15 mph, with gusts as high as 25 mph.
Sunday Night
A 20 percent chance of showers. Cloudy, with a low around 52. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
Mostly cloudy, with a high near 68. Northeast wind 5 to 10 mph.
Monday Night
Mostly cloudy, with a low around 49. Northeast wind around 5 mph becoming calm in the evening.
Tuesday
Mostly cloudy, with a high near 71.
Tuesday Night
Mostly cloudy, with a low around 52.
Wednesday
Mostly cloudy, with a high near 77.
Wednesday Night
Mostly cloudy, with a low around 59.
Thursday
A 20 percent chance of showers. Mostly cloudy, with a high near 80.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.91°W (Elev. 597 ft)
Last Update:
2:42 am CDT Apr 3, 2026
Forecast Valid:
3am CDT Apr 3, 2026-6pm CDT Apr 9, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

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