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

63°F

17°C

Humidity 78%
Wind Speed N 5 mph
Barometer 29.95 in (1013.3 mb)
Dewpoint 56°F (13°C)
Visibility 10.00 mi
Last update 27 Feb 1:56 am CST
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Mostly clear, with a low around 59. North northeast wind around 5 mph.

    Low: 59 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 85. North wind 5 to 10 mph becoming east in the afternoon.

    High: 85 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 57. East wind around 5 mph becoming calm in the evening.

    Low: 57 °F

    Mostly Clear

  • Saturday

    Saturday: Patchy fog between 7am and 8am. Otherwise, sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 60. South wind 5 to 10 mph.

    Low: 60 °F

    Partly Cloudy

  • Sunday

    Sunday: Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 84 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 60. South wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 60 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 59. Southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 59 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Mostly clear, with a low around 59. North northeast wind around 5 mph.
Friday
Sunny, with a high near 85. North wind 5 to 10 mph becoming east in the afternoon.
Friday Night
Mostly clear, with a low around 57. East wind around 5 mph becoming calm in the evening.
Saturday
Patchy fog between 7am and 8am. Otherwise, sunny, with a high near 85. South wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Partly cloudy, with a low around 60. South wind 5 to 10 mph.
Sunday
Mostly sunny, with a high near 84. South wind 5 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Partly cloudy, with a low around 60. South wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Mostly sunny, with a high near 82. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 59. Southeast wind around 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly cloudy, with a high near 84.
Tuesday Night
A 30 percent chance of showers. Mostly cloudy, with a low around 64.
Wednesday
A 40 percent chance of showers. Mostly cloudy, with a high near 83.
Wednesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 65.
Thursday
A 30 percent chance of showers. Partly sunny, with a high near 84.
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:
2:32 am CST Feb 27, 2026
Forecast Valid:
3am CST Feb 27, 2026-6pm CST Mar 5, 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