National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce

Areas of Severe Thunderstorms and Excessive Rainfall Through This Weekend

Severe thunderstorms which can bring large hail, damaging winds, and isolated tornadoes will be possible over parts of the central U.S. through this weekend. Thunderstorms with heavy to excessive rainfall moving from Texas into the mid-Mississippi Valley through this weekend may produce areas of flooding. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

79°F

26°C

Humidity 90%
Wind Speed S 8 mph
Barometer 29.82 in (1009.0 mb)
Dewpoint 76°F (24°C)
Visibility 10.00 mi
Heat Index83°F (28°C)
Last update 7 Jun 5:56 am CDT
Extended Forecast for

San Marcos TX

  • Today

    Today: Mostly cloudy, with a high near 89. Heat index values as high as 100. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 89 °F

    Mostly Cloudy

  • Tonight

    Tonight: Mostly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Mostly Cloudy

  • Monday

    Monday: A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 90 °F

    Mostly Cloudy
    then Slight
    Chance
    T-storms

  • Monday Night

    Monday Night: Increasing clouds, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: Mostly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 91 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 75 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 91 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 76 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 93. South wind around 10 mph, with gusts as high as 20 mph.

    High: 93 °F

    Partly Sunny

Detailed Forecast

Today
Mostly cloudy, with a high near 89. Heat index values as high as 100. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tonight
Mostly cloudy, with a low around 75. South southeast wind 5 to 15 mph, with gusts as high as 20 mph.
Monday
A 20 percent chance of showers and thunderstorms after 1pm. Mostly cloudy, then gradually becoming sunny, with a high near 90. South wind 5 to 10 mph, with gusts as high as 20 mph.
Monday Night
Increasing clouds, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday
Mostly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 75. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Partly sunny, with a high near 91. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Partly cloudy, with a low around 76. South southeast wind 10 to 15 mph, with gusts as high as 20 mph.
Thursday
Partly sunny, with a high near 93. South wind around 10 mph, with gusts as high as 20 mph.
Thursday Night
Partly cloudy, with a low around 75.
Friday
Mostly sunny, with a high near 94.
Friday Night
Mostly clear, with a low around 74.
Saturday
Mostly sunny, with a high near 93.
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:
5:32 am CDT Jun 7, 2026
Forecast Valid:
6am CDT Jun 7, 2026-6pm CDT Jun 13, 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