National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

72°F

22°C

Humidity 68%
Wind Speed SE 3 mph
Barometer 30.07 in (1017.5 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 12 May 9:56 pm CDT
Extended Forecast for

San Marcos TX

  • Tonight

    Tonight: Clear, with a low around 63. East southeast wind around 5 mph becoming calm.

    Low: 63 °F

    Clear

  • Wednesday

    Wednesday: Sunny, with a high near 89. Calm wind becoming southeast around 5 mph in the afternoon.

    High: 89 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 64. Southeast wind around 5 mph becoming south southwest after midnight.

    Low: 64 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 90 °F

    Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 68. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 68 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 72. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 72 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly cloudy, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 91 °F

    Mostly Cloudy

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 76. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.

    Low: 76 °F

    Mostly Cloudy

Detailed Forecast

Tonight
Clear, with a low around 63. East southeast wind around 5 mph becoming calm.
Wednesday
Sunny, with a high near 89. Calm wind becoming southeast around 5 mph in the afternoon.
Wednesday Night
Mostly clear, with a low around 64. Southeast wind around 5 mph becoming south southwest after midnight.
Thursday
Sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Partly cloudy, with a low around 68. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Friday
Mostly sunny, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.
Friday Night
Partly cloudy, with a low around 72. South southeast wind 10 to 15 mph, with gusts as high as 25 mph.
Saturday
Mostly cloudy, with a high near 91. South wind 10 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Mostly cloudy, with a low around 76. South southeast wind 10 to 20 mph, with gusts as high as 30 mph.
Sunday
Mostly cloudy, with a high near 91.
Sunday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 78.
Monday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 89.
Monday Night
Showers and thunderstorms likely. Mostly cloudy, with a low around 76. Chance of precipitation is 60%.
Tuesday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 86.
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:
6:44 pm CDT May 12, 2026
Forecast Valid:
10pm CDT May 12, 2026-6pm CDT May 19, 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