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 44%
Wind Speed S 12 mph
Barometer 29.88 in (1011.4 mb)
Dewpoint 59°F (15°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 5 Nov 1:56 pm CST
Extended Forecast for

San Marcos Municipal Airport TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 82. South wind around 5 mph.

    High: 82 °F

    Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 56. Light and variable wind becoming north northwest 10 to 15 mph after midnight. Winds could gust as high as 20 mph.

    Low: 56 °F

    Partly Cloudy

  • Friday

    Friday: Partly sunny, then gradually becoming sunny, with a high near 76. North wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 76 °F

    Becoming
    Sunny

  • Friday Night

    Friday Night: Increasing clouds, with a low around 55. North northeast wind 5 to 10 mph.

    Low: 55 °F

    Increasing
    Clouds

  • Saturday

    Saturday: A 30 percent chance of showers after noon. Cloudy, with a high near 71. North northeast wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 71 °F

    Cloudy then
    Chance
    Showers

  • Saturday Night

    Saturday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 51. North northeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    Low: 51 °F

    Showers
    Likely

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm. Cloudy, with a high near 64. North northeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 70%.

    High: 64 °F

    Showers
    Likely

  • Sunday Night

    Sunday Night: A 30 percent chance of showers. Mostly cloudy, with a low around 48. North northeast wind around 5 mph becoming calm in the evening.

    Low: 48 °F

    Chance
    Showers

  • Monday

    Monday: A 30 percent chance of showers, mainly before noon. Partly sunny, with a high near 67. Calm wind.

    High: 67 °F

    Chance
    Showers

Detailed Forecast

This Afternoon
Sunny, with a high near 82. South wind around 5 mph.
Tonight
Partly cloudy, with a low around 56. Light and variable wind becoming north northwest 10 to 15 mph after midnight. Winds could gust as high as 20 mph.
Friday
Partly sunny, then gradually becoming sunny, with a high near 76. North wind 10 to 15 mph, with gusts as high as 25 mph.
Friday Night
Increasing clouds, with a low around 55. North northeast wind 5 to 10 mph.
Saturday
A 30 percent chance of showers after noon. Cloudy, with a high near 71. North northeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 51. North northeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Sunday
Showers likely and possibly a thunderstorm. Cloudy, with a high near 64. North northeast wind 5 to 15 mph, with gusts as high as 20 mph. Chance of precipitation is 70%.
Sunday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 48. North northeast wind around 5 mph becoming calm in the evening.
Monday
A 30 percent chance of showers, mainly before noon. Partly sunny, with a high near 67. Calm wind.
Monday Night
Partly cloudy, with a low around 47.
Tuesday
Mostly sunny, with a high near 72.
Tuesday Night
Partly cloudy, with a low around 50.
Veterans Day
Partly sunny, with a high near 75.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.88°N 97.86°W (Elev. 600 ft)
Last Update:
1:48 pm CST Nov 5, 2026
Forecast Valid:
2pm CST Nov 5, 2026-6pm CST Nov 11, 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