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.

Fair

83°F

28°C

Humidity 41%
Wind Speed S 10 G 21 mph
Barometer 30.10 in (1018.6 mb)
Dewpoint 57°F (14°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 24 Mar 12:56 pm CDT
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 86. South wind around 10 mph.

    High: 86 °F

    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 65. South southeast wind 5 to 10 mph.

    Low: 65 °F

    Increasing
    Clouds

  • Wednesday

    Wednesday: Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 88. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 88 °F

    Patchy Fog
    then Sunny

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 63 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Mostly sunny, with a high near 89. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 89 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 62. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 62 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 89. South wind 5 to 10 mph becoming east southeast in the afternoon.

    High: 89 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 59. Northeast wind 5 to 10 mph.

    Low: 59 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny, with a high near 82. North northeast wind around 10 mph.

    High: 82 °F

    Partly Sunny

Detailed Forecast

This Afternoon
Sunny, with a high near 86. South wind around 10 mph.
Tonight
Increasing clouds, with a low around 65. South southeast wind 5 to 10 mph.
Wednesday
Patchy fog before 8am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 88. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Increasing clouds, with a low around 63. South southeast wind around 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny, with a high near 89. South wind 10 to 15 mph, with gusts as high as 25 mph.
Thursday Night
Mostly clear, with a low around 62. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Friday
Mostly sunny, with a high near 89. South wind 5 to 10 mph becoming east southeast in the afternoon.
Friday Night
Partly cloudy, with a low around 59. Northeast wind 5 to 10 mph.
Saturday
Partly sunny, with a high near 82. North northeast wind around 10 mph.
Saturday Night
Mostly clear, with a low around 55.
Sunday
Sunny, with a high near 84.
Sunday Night
Partly cloudy, with a low around 59.
Monday
Partly sunny, with a high near 87.
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 97.94°W (Elev. 577 ft)
Last Update:
1:24 pm CDT Mar 24, 2026
Forecast Valid:
1pm CDT Mar 24, 2026-6pm CDT Mar 30, 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