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 75%
Wind Speed NW 7 mph
Barometer 30.17 in (1021.3 mb)
Dewpoint 44°F (7°C)
Visibility 10.00 mi
Wind Chill50°F (10°C)
Last update 7 Apr 12:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Partly cloudy, with a low around 48. North northeast wind around 5 mph.

    Low: 48 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 75. North wind around 5 mph becoming east southeast in the afternoon.

    High: 75 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 53. East wind around 5 mph becoming calm after midnight.

    Low: 53 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 77. Calm wind becoming southeast around 5 mph in the morning.

    High: 77 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 62. Southeast wind around 5 mph.

    Low: 62 °F

    Mostly Cloudy

  • Thursday

    Thursday: A 40 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. Light east southeast wind becoming southeast 5 to 10 mph in the morning.

    High: 81 °F

    Mostly Cloudy
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63. Southeast wind 5 to 10 mph.

    Low: 63 °F

    Chance
    T-storms

  • Friday

    Friday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.

    High: 78 °F

    Chance
    T-storms then
    Showers
    Likely

  • Friday Night

    Friday Night: A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 65. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 65 °F

    Slight Chance
    T-storms

Detailed Forecast

Overnight
Partly cloudy, with a low around 48. North northeast wind around 5 mph.
Tuesday
Partly sunny, with a high near 75. North wind around 5 mph becoming east southeast in the afternoon.
Tuesday Night
Partly cloudy, with a low around 53. East wind around 5 mph becoming calm after midnight.
Wednesday
Partly sunny, with a high near 77. Calm wind becoming southeast around 5 mph in the morning.
Wednesday Night
Mostly cloudy, with a low around 62. Southeast wind around 5 mph.
Thursday
A 40 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. Light east southeast wind becoming southeast 5 to 10 mph in the morning.
Thursday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 63. Southeast wind 5 to 10 mph.
Friday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 78. Southeast wind 5 to 10 mph, with gusts as high as 20 mph. Chance of precipitation is 60%.
Friday Night
A 20 percent chance of showers and thunderstorms before 1am. Mostly cloudy, with a low around 65. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday
A 50 percent chance of showers and thunderstorms, mainly after 1pm. Mostly cloudy, with a high near 81.
Saturday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 67.
Sunday
A 50 percent chance of showers and thunderstorms. Cloudy, with a high near 81.
Sunday Night
A 20 percent chance of showers and thunderstorms. Cloudy, with a low around 69.
Monday
A 30 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:
12:42 am CDT Apr 7, 2026
Forecast Valid:
1am CDT Apr 7, 2026-6pm CDT Apr 13, 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