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 84%
Wind Speed SE 12 mph
Barometer 29.97 in (1014.3 mb)
Dewpoint 66°F (19°C)
Visibility 10.00 mi
Last update 15 Apr 11:56 pm CDT
Extended Forecast for

3 Miles WNW San Marcos TX

  • Overnight

    Overnight: Mostly cloudy, with a low around 68. South wind around 5 mph.

    Low: 68 °F

    Mostly Cloudy

  • Thursday

    Thursday: Cloudy, then gradually becoming mostly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 87 °F

    Decreasing
    Clouds

  • Thursday Night

    Thursday Night: Increasing clouds, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 67 °F

    Increasing
    Clouds

  • Friday

    Friday: Cloudy, then gradually becoming mostly sunny, with a high near 89. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 89 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 66. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 66 °F

    Mostly Cloudy

  • Saturday

    Saturday: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 77. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 60%.

    High: 77 °F

    Chance
    T-storms then
    Showers
    Likely

  • Saturday Night

    Saturday Night: A 50 percent chance of showers and thunderstorms. Cloudy, with a low around 53. North northeast wind around 15 mph, with gusts as high as 25 mph.

    Low: 53 °F

    Chance
    T-storms

  • Sunday

    Sunday: A 20 percent chance of showers. Mostly cloudy, with a high near 69. Northeast wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 69 °F

    Slight Chance
    Showers

  • Sunday Night

    Sunday Night: A slight chance of showers, then a chance of showers and thunderstorms after 1am. Cloudy, with a low around 55. Northeast wind 5 to 10 mph. Chance of precipitation is 30%.

    Low: 55 °F

    Chance
    Showers

Detailed Forecast

Overnight
Mostly cloudy, with a low around 68. South wind around 5 mph.
Thursday
Cloudy, then gradually becoming mostly sunny, with a high near 87. South wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday Night
Increasing clouds, with a low around 67. South southeast wind around 10 mph, with gusts as high as 20 mph.
Friday
Cloudy, then gradually becoming mostly sunny, with a high near 89. South wind 10 to 15 mph, with gusts as high as 30 mph.
Friday Night
Mostly cloudy, with a low around 66. South southeast wind 5 to 15 mph, with gusts as high as 25 mph.
Saturday
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1pm. Mostly cloudy, with a high near 77. South wind 5 to 15 mph becoming north in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 60%.
Saturday Night
A 50 percent chance of showers and thunderstorms. Cloudy, with a low around 53. North northeast wind around 15 mph, with gusts as high as 25 mph.
Sunday
A 20 percent chance of showers. Mostly cloudy, with a high near 69. Northeast wind 10 to 15 mph, with gusts as high as 25 mph.
Sunday Night
A slight chance of showers, then a chance of showers and thunderstorms after 1am. Cloudy, with a low around 55. Northeast wind 5 to 10 mph. Chance of precipitation is 30%.
Monday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 64.
Monday Night
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 56.
Tuesday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 74.
Tuesday Night
Mostly cloudy, with a low around 63.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
3 Miles WNW San Marcos TX
 29.9°N 97.97°W (Elev. 686 ft)
Last Update:
11:32 pm CDT Apr 15, 2026
Forecast Valid:
12am CDT Apr 16, 2026-6pm CDT Apr 22, 2026
 
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