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

71°F

22°C

Humidity 63%
Wind Speed NE 3 mph
Barometer 29.93 in (1012.9 mb)
Dewpoint 58°F (14°C)
Visibility 10.00 mi
Last update 21 May 12:56 am CDT
Extended Forecast for

San Marcos TX

  • Overnight

    Overnight: Mostly cloudy, with a low around 66. North northeast wind around 5 mph.

    Low: 66 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 95. North northeast wind around 5 mph becoming southeast in the afternoon.

    High: 95 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly cloudy, with a low around 72. East southeast wind around 5 mph becoming calm after midnight.

    Low: 72 °F

    Mostly Cloudy

  • Thursday

    Thursday: Patchy fog before 8am. Otherwise, mostly cloudy, then gradually becoming sunny and hot, with a high near 99. Light south wind becoming southeast 5 to 10 mph in the afternoon.

    High: 99 °F

    Patchy Fog
    then Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 71. Southeast wind 5 to 10 mph.

    Low: 71 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 96. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 96 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 73. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 73 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 97 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    Low: 75 °F

    Partly Cloudy

Detailed Forecast

Overnight
Mostly cloudy, with a low around 66. North northeast wind around 5 mph.
Wednesday
Mostly sunny, with a high near 95. North northeast wind around 5 mph becoming southeast in the afternoon.
Wednesday Night
Mostly cloudy, with a low around 72. East southeast wind around 5 mph becoming calm after midnight.
Thursday
Patchy fog before 8am. Otherwise, mostly cloudy, then gradually becoming sunny and hot, with a high near 99. Light south wind becoming southeast 5 to 10 mph in the afternoon.
Thursday Night
Partly cloudy, with a low around 71. Southeast wind 5 to 10 mph.
Friday
Mostly sunny, with a high near 96. South wind 5 to 10 mph, with gusts as high as 20 mph.
Friday Night
Partly cloudy, with a low around 73. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Saturday
Mostly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 25 mph.
Saturday Night
Partly cloudy, with a low around 75. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Sunday
A 20 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 97.
Sunday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 69.
Memorial Day
A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 88.
Monday Night
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 65.
Tuesday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 84.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
1:16 am CDT May 21, 2025
Forecast Valid:
1am CDT May 21, 2025-6pm CDT May 27, 2025
 
Forecast Discussion
 
Get as KML Get as XML

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