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

84°F

29°C

Humidity 34%
Wind Speed S 14 G 20 mph
Barometer 30.05 in (1017.0 mb)
Dewpoint 53°F (12°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 9 Feb 2:56 pm CST
Extended Forecast for

San Marcos TX

  • This Afternoon

    This Afternoon: Sunny, with a high near 83. South wind 5 to 10 mph.

    High: 83 °F

    Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 59. South wind 5 to 10 mph.

    Low: 59 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Patchy fog between 7am and 10am. Otherwise, mostly cloudy, with a high near 76. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 76 °F

    Patchy Fog
    then Mostly
    Cloudy

  • Tuesday Night

    Tuesday Night: A 40 percent chance of showers. Mostly cloudy, with a low around 59. Southeast wind around 5 mph becoming calm in the evening.

    Low: 59 °F

    Chance
    Showers

  • Wednesday

    Wednesday: A 20 percent chance of showers before noon. Partly sunny, with a high near 76. Calm wind becoming north around 5 mph in the morning.

    High: 76 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 57. Northeast wind around 5 mph becoming calm in the evening.

    Low: 57 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 81. Calm wind becoming south around 5 mph in the afternoon.

    High: 81 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 61. South wind around 5 mph.

    Low: 61 °F

    Partly Cloudy

  • Friday

    Friday: A 20 percent chance of showers after noon. Mostly cloudy, with a high near 82. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 82 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

Detailed Forecast

This Afternoon
Sunny, with a high near 83. South wind 5 to 10 mph.
Tonight
Increasing clouds, with a low around 59. South wind 5 to 10 mph.
Tuesday
Patchy fog between 7am and 10am. Otherwise, mostly cloudy, with a high near 76. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
A 40 percent chance of showers. Mostly cloudy, with a low around 59. Southeast wind around 5 mph becoming calm in the evening.
Wednesday
A 20 percent chance of showers before noon. Partly sunny, with a high near 76. Calm wind becoming north around 5 mph in the morning.
Wednesday Night
Partly cloudy, with a low around 57. Northeast wind around 5 mph becoming calm in the evening.
Thursday
Partly sunny, with a high near 81. Calm wind becoming south around 5 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 61. South wind around 5 mph.
Friday
A 20 percent chance of showers after noon. Mostly cloudy, with a high near 82. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Showers likely, mainly after midnight. Mostly cloudy, with a low around 61. Chance of precipitation is 60%.
Saturday
Showers and thunderstorms likely. Mostly sunny, with a high near 78. Chance of precipitation is 60%.
Saturday Night
Clear, with a low around 50.
Sunday
Sunny, with a high near 75.
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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 pm CST Feb 9, 2026
Forecast Valid:
3pm CST Feb 9, 2026-6pm CST Feb 15, 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