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

79°F

26°C

Humidity 32%
Wind Speed N 6 mph
Barometer 30.06 in (1017.2 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Heat Index79°F (26°C)
Last update 12 Nov 1:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 75. North northeast wind around 5 mph becoming calm.

    High: 75 °F

    Sunny

  • Tonight

    Tonight: Clear, with a low around 52. Calm wind becoming west northwest around 5 mph after midnight.

    Low: 52 °F

    Clear

  • Friday

    Friday: Sunny, with a high near 76. West northwest wind around 5 mph becoming calm in the morning.

    High: 76 °F

    Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 51. Southeast wind around 5 mph becoming calm.

    Low: 51 °F

    Partly Cloudy

  • Saturday

    Saturday: A 30 percent chance of showers after noon. Partly sunny, with a high near 68. Northeast wind 5 to 15 mph becoming east southeast in the afternoon. Winds could gust as high as 25 mph.

    High: 68 °F

    Partly Sunny
    then Chance
    Showers

  • Saturday Night

    Saturday Night: Showers likely, mainly after midnight. Cloudy, with a low around 55. East southeast wind 5 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.

    Low: 55 °F

    Showers
    Likely

  • Sunday

    Sunday: Showers and possibly a thunderstorm. High near 67. Southeast wind around 10 mph, with gusts as high as 25 mph. Chance of precipitation is 80%.

    High: 67 °F

    Showers

  • Sunday Night

    Sunday Night: A 30 percent chance of showers, mainly before midnight. Mostly cloudy, with a low around 51. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.

    Low: 51 °F

    Chance
    Showers

  • Monday

    Monday: Mostly cloudy, with a high near 59. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 59 °F

    Mostly Cloudy

Detailed Forecast

This Afternoon
Sunny, with a high near 75. North northeast wind around 5 mph becoming calm.
Tonight
Clear, with a low around 52. Calm wind becoming west northwest around 5 mph after midnight.
Friday
Sunny, with a high near 76. West northwest wind around 5 mph becoming calm in the morning.
Friday Night
Partly cloudy, with a low around 51. Southeast wind around 5 mph becoming calm.
Saturday
A 30 percent chance of showers after noon. Partly sunny, with a high near 68. Northeast wind 5 to 15 mph becoming east southeast in the afternoon. Winds could gust as high as 25 mph.
Saturday Night
Showers likely, mainly after midnight. Cloudy, with a low around 55. East southeast wind 5 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 60%.
Sunday
Showers and possibly a thunderstorm. High near 67. Southeast wind around 10 mph, with gusts as high as 25 mph. Chance of precipitation is 80%.
Sunday Night
A 30 percent chance of showers, mainly before midnight. Mostly cloudy, with a low around 51. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.
Monday
Mostly cloudy, with a high near 59. North northeast wind 10 to 15 mph, with gusts as high as 30 mph.
Monday Night
Mostly cloudy, with a low around 50.
Tuesday
Mostly cloudy, with a high near 60.
Tuesday Night
Mostly cloudy, with a low around 52.
Wednesday
A 20 percent chance of showers. Mostly cloudy, with a high near 64.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
1:46 pm CST Nov 12, 2026
Forecast Valid:
2pm CST Nov 12, 2026-6pm CST Nov 18, 2026
 
Forecast Discussion
 
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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