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

52°F

11°C

Humidity 80%
Wind Speed N 7 mph
Barometer 30.30 in (1025.9 mb)
Dewpoint 46°F (8°C)
Visibility 10.00 mi
Wind Chill50°F (10°C)
Last update 5 Apr 11:56 pm CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Partly cloudy, with a low around 51. North wind around 5 mph.

    Low: 51 °F

    Partly Cloudy

  • Monday

    Monday: Sunny, with a high near 71. Northeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 71 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 49. North northeast wind around 5 mph.

    Low: 49 °F

    Mostly Clear

  • Tuesday

    Tuesday: Partly sunny, with a high near 73. Calm wind becoming east around 5 mph in the morning.

    High: 73 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 54. East wind around 5 mph becoming calm after midnight.

    Low: 54 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 76. Calm wind becoming east southeast around 5 mph in the afternoon.

    High: 76 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 60. East southeast wind around 5 mph becoming calm after midnight.

    Low: 60 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. Light southeast wind increasing to 5 to 10 mph in the morning.

    High: 82 °F

    Cloudy then
    Slight Chance
    T-storms

  • Thursday Night

    Thursday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 63. Southeast wind 5 to 10 mph.

    Low: 63 °F

    Slight Chance
    T-storms

Detailed Forecast

Overnight
Partly cloudy, with a low around 51. North wind around 5 mph.
Monday
Sunny, with a high near 71. Northeast wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Mostly clear, with a low around 49. North northeast wind around 5 mph.
Tuesday
Partly sunny, with a high near 73. Calm wind becoming east around 5 mph in the morning.
Tuesday Night
Mostly cloudy, with a low around 54. East wind around 5 mph becoming calm after midnight.
Wednesday
Partly sunny, with a high near 76. Calm wind becoming east southeast around 5 mph in the afternoon.
Wednesday Night
Mostly cloudy, with a low around 60. East southeast wind around 5 mph becoming calm after midnight.
Thursday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. Light southeast wind increasing to 5 to 10 mph in the morning.
Thursday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 63. Southeast wind 5 to 10 mph.
Friday
A 30 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 82.
Friday Night
Mostly cloudy, with a low around 65.
Saturday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 80.
Saturday Night
A 40 percent chance of showers and thunderstorms. Cloudy, with a low around 68.
Sunday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 83.
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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:
11:54 pm CDT Apr 5, 2026
Forecast Valid:
12am CDT Apr 6, 2026-6pm CDT Apr 12, 2026
 
Forecast Discussion
 
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Additional Resources

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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