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.

Overcast

62°F

17°C

Humidity 96%
Wind Speed SE 3 mph
Barometer 30.03 in (1016.8 mb)
Dewpoint 61°F (16°C)
Visibility 10.00 mi
Last update 9 Mar 1:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Patchy fog. Otherwise, cloudy, with a low around 61. South southwest wind around 5 mph.

    Low: 61 °F

    Patchy Fog

  • Monday

    Monday: Areas of fog before 1pm. Otherwise, mostly cloudy, with a high near 83. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.

    High: 83 °F

    Areas Fog

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 67. South wind around 10 mph.

    Low: 67 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: A 30 percent chance of showers and thunderstorms after 1pm. Cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 82 °F

    Cloudy then
    Chance
    Showers

  • Tuesday Night

    Tuesday Night: A chance of showers before 10pm, then a chance of showers and thunderstorms between 10pm and 1am, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 70%.

    Low: 63 °F

    Chance
    Showers then
    Showers
    Likely

  • Wednesday

    Wednesday: A 50 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 81. South southwest wind 5 to 10 mph becoming west northwest in the afternoon. Winds could gust as high as 20 mph.

    High: 81 °F

    Chance
    T-storms then
    Chance
    Showers

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 48. North wind around 15 mph, with gusts as high as 25 mph.

    Low: 48 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 69. North wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 69 °F

    Sunny

  • Thursday Night

    Thursday Night: Clear, with a low around 47. East wind around 5 mph becoming calm in the evening.

    Low: 47 °F

    Clear

Detailed Forecast

Overnight
Patchy fog. Otherwise, cloudy, with a low around 61. South southwest wind around 5 mph.
Monday
Areas of fog before 1pm. Otherwise, mostly cloudy, with a high near 83. Light south wind increasing to 5 to 10 mph in the morning. Winds could gust as high as 20 mph.
Monday Night
Mostly cloudy, with a low around 67. South wind around 10 mph.
Tuesday
A 30 percent chance of showers and thunderstorms after 1pm. Cloudy, with a high near 82. South wind 10 to 15 mph, with gusts as high as 30 mph.
Tuesday Night
A chance of showers before 10pm, then a chance of showers and thunderstorms between 10pm and 1am, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 63. South southeast wind 10 to 15 mph, with gusts as high as 30 mph. Chance of precipitation is 70%.
Wednesday
A 50 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 81. South southwest wind 5 to 10 mph becoming west northwest in the afternoon. Winds could gust as high as 20 mph.
Wednesday Night
Mostly clear, with a low around 48. North wind around 15 mph, with gusts as high as 25 mph.
Thursday
Sunny, with a high near 69. North wind 5 to 15 mph, with gusts as high as 25 mph.
Thursday Night
Clear, with a low around 47. East wind around 5 mph becoming calm in the evening.
Friday
Sunny, with a high near 81.
Friday Night
Clear, with a low around 54.
Saturday
Sunny, with a high near 85.
Saturday Night
Mostly clear, with a low around 60.
Sunday
Mostly sunny, with a high near 88.
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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:
2:06 am CDT Mar 9, 2026
Forecast Valid:
2am CDT Mar 9, 2026-6pm CDT Mar 15, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

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Chance of Precipitation