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

69°F

21°C

Humidity 93%
Wind Speed NE 10 mph
Barometer 29.94 in (1013.4 mb)
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 2 Apr 9:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: A 30 percent chance of showers and thunderstorms before 1pm. Mostly cloudy, with a high near 85. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 85 °F

    Chance
    T-storms

  • Tonight

    Tonight: Increasing clouds, with a low around 68. South wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 68 °F

    Increasing
    Clouds

  • Friday

    Friday: Mostly cloudy, with a high near 88. South southeast wind 10 to 15 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 69. South southeast wind 10 to 20 mph, with gusts as high as 30 mph. Chance of precipitation is 40%.

    Low: 69 °F

    Slight Chance
    T-storms then
    Chance
    Showers

  • Saturday

    Saturday: Showers and possibly a thunderstorm. High near 80. South southeast wind 5 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 90%.

    High: 80 °F

    Showers

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Cloudy, with a low around 54. North northeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.

    Low: 54 °F

    Chance
    Showers

  • Sunday

    Sunday: A 30 percent chance of showers, mainly before 1pm. Cloudy, with a high near 67. North northeast wind around 15 mph, with gusts as high as 25 mph.

    High: 67 °F

    Chance
    Showers

  • Sunday Night

    Sunday Night: A 20 percent chance of showers. Cloudy, with a low around 53. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 53 °F

    Slight Chance
    Showers

  • Monday

    Monday: A 20 percent chance of showers before 1pm. Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.

    High: 70 °F

    Slight Chance
    Showers

Detailed Forecast

Today
A 30 percent chance of showers and thunderstorms before 1pm. Mostly cloudy, with a high near 85. South wind 10 to 15 mph, with gusts as high as 25 mph.
Tonight
Increasing clouds, with a low around 68. South wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
Mostly cloudy, with a high near 88. South southeast wind 10 to 15 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 69. 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 80. South southeast wind 5 to 10 mph becoming north in the afternoon. Winds could gust as high as 20 mph. Chance of precipitation is 90%.
Saturday Night
A chance of showers and thunderstorms. Cloudy, with a low around 54. North northeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%.
Sunday
A 30 percent chance of showers, mainly before 1pm. Cloudy, with a high near 67. 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 53. North northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday
A 20 percent chance of showers before 1pm. Partly sunny, with a high near 70. Northeast wind 5 to 10 mph.
Monday Night
Partly cloudy, with a low around 48.
Tuesday
Mostly cloudy, with a high near 73.
Tuesday Night
Mostly cloudy, with a low around 51.
Wednesday
Mostly sunny, with a high near 78.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.91°W (Elev. 597 ft)
Last Update:
6:42 am CDT Apr 2, 2026
Forecast Valid:
10am CDT Apr 2, 2026-6pm CDT Apr 8, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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