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

66°F

19°C

Humidity 93%
Wind Speed S 9 mph
Barometer 29.69 in (1004.8 mb)
Dewpoint 64°F (18°C)
Visibility 10.00 mi
Last update 19 Feb 2:56 am CST
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Patchy fog. Otherwise, mostly cloudy, with a low around 64. South southwest wind around 5 mph.

    Low: 64 °F

    Patchy Fog

  • Thursday

    Thursday: Patchy fog before 9am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 85. South southwest wind around 5 mph becoming north northeast in the afternoon.

    High: 85 °F

    Patchy Fog
    then Sunny

  • Thursday Night

    Thursday Night: Patchy fog after 3am. Otherwise, increasing clouds, with a low around 59. East northeast wind around 5 mph becoming calm.

    Low: 59 °F

    Mostly Clear
    then Patchy
    Fog

  • Friday

    Friday: Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 77. North northeast wind around 5 mph becoming southeast in the afternoon.

    High: 77 °F

    Patchy Fog
    then Partly
    Sunny

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 60. Southeast wind around 5 mph becoming calm.

    Low: 60 °F

    Mostly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 77. North wind 5 to 15 mph, with gusts as high as 25 mph.

    High: 77 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 43. North wind around 15 mph, with gusts as high as 25 mph.

    Low: 43 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 64. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 64 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 39. North northeast wind 5 to 10 mph.

    Low: 39 °F

    Partly Cloudy

Detailed Forecast

Overnight
Patchy fog. Otherwise, mostly cloudy, with a low around 64. South southwest wind around 5 mph.
Thursday
Patchy fog before 9am. Otherwise, cloudy through mid morning, then gradual clearing, with a high near 85. South southwest wind around 5 mph becoming north northeast in the afternoon.
Thursday Night
Patchy fog after 3am. Otherwise, increasing clouds, with a low around 59. East northeast wind around 5 mph becoming calm.
Friday
Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 77. North northeast wind around 5 mph becoming southeast in the afternoon.
Friday Night
Mostly cloudy, with a low around 60. Southeast wind around 5 mph becoming calm.
Saturday
Mostly sunny, with a high near 77. North wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Mostly clear, with a low around 43. North wind around 15 mph, with gusts as high as 25 mph.
Sunday
Sunny, with a high near 64. North northeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
Partly cloudy, with a low around 39. North northeast wind 5 to 10 mph.
Monday
Sunny, with a high near 64.
Monday Night
Mostly clear, with a low around 38.
Tuesday
Mostly sunny, with a high near 72.
Tuesday Night
Partly cloudy, with a low around 53.
Wednesday
Partly sunny, with a high near 82.
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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:
12:46 am CST Feb 19, 2026
Forecast Valid:
3am CST Feb 19, 2026-6pm CST Feb 25, 2026
 
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Additional Resources

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