Heavy to Excessive Rainfall and Flooding Threats in the Central and Eastern U.S.; Heat and Fire Weather Concerns in the West

Thunderstorms producing excessive rainfall and potential flooding concerns will continue through tonight from the Southern Plains to the East Coast. Areas of greatest concern for flooding are over central Texas and the Mid-Atlantic. Heat will continue to build across the West through Tuesday. Heat Advisories and Extreme Heat Warnings are in effect. Fire Weather concerns continue through Monday. Read More >

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Overcast

76°F

24°C

Humidity 100%
Wind Speed S 8 mph
Barometer 30.04 in (1016.7 mb)
Dewpoint 76°F (24°C)
Visibility 9.00 mi
Heat Index75°F (24°C)
Last update 14 Jul 4:56 am CDT
Extended Forecast for

San Marcos Municipal Airport TX

  • Today

    Today: A slight chance of showers between 7am and 1pm, then a slight chance of showers and thunderstorms after 1pm.  Partly sunny, with a high near 92. Heat index values as high as 102. South wind 5 to 10 mph.  Chance of precipitation is 20%.

    High: 92 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

  • Tonight

    Tonight: Mostly cloudy, with a low around 74. Southeast wind 5 to 10 mph.

    Low: 74 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Cloudy, then gradually becoming mostly sunny, with a high near 93. Heat index values as high as 102. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 93 °F

    Decreasing
    Clouds

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 74. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 94 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.

    Low: 72 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 94. South wind 5 to 10 mph.

    High: 94 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around 72. South southeast wind around 5 mph.

    Low: 72 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 94. Calm wind becoming south around 5 mph in the morning.

    High: 94 °F

    Mostly Sunny

Detailed Forecast

Today
A slight chance of showers between 7am and 1pm, then a slight chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 92. Heat index values as high as 102. South wind 5 to 10 mph. Chance of precipitation is 20%.
Tonight
Mostly cloudy, with a low around 74. Southeast wind 5 to 10 mph.
Tuesday
Cloudy, then gradually becoming mostly sunny, with a high near 93. Heat index values as high as 102. South wind 5 to 10 mph, with gusts as high as 20 mph.
Tuesday Night
Partly cloudy, with a low around 74. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday
Mostly sunny, with a high near 94. South wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday Night
Mostly clear, with a low around 72. South southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Thursday
Mostly sunny, with a high near 94. South wind 5 to 10 mph.
Thursday Night
Partly cloudy, with a low around 72. South southeast wind around 5 mph.
Friday
Mostly sunny, with a high near 94. Calm wind becoming south around 5 mph in the morning.
Friday Night
Mostly cloudy, with a low around 74.
Saturday
Mostly sunny, with a high near 95.
Saturday Night
Partly cloudy, with a low around 75.
Sunday
Mostly sunny, with a high near 96.
Basemap Options
Click map to change the forecast location
Loading map...

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos Municipal Airport TX
 29.9°N 97.89°W (Elev. 604 ft)
5:32 am CDT Jul 14, 2025
5am CDT Jul 14, 2025-6pm CDT Jul 20, 2025
 
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