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Hazardous Weather Conditions

Current conditions at

San Marcos, San Marcos Municipal Airport (KHYI)

Lat: 29.89°NLon: 97.86°WElev: 597ft.

Fair

93°F

34°C

Humidity 54%
Wind Speed SE 15 mph
Barometer 29.70 in (1005.1 mb)
Dewpoint 74°F (23°C)
Visibility 10.00 mi
Heat Index103°F (39°C)
Last update 15 May 6:56 pm CDT
Extended Forecast for

San Marcos TX

Heat Advisory May 16, 02:00pm until May 16, 07:00pm
Click here for hazard details and duration
Heat Advisory

  • Tonight

    Tonight: Increasing clouds, with a low around 74. South southeast wind around 10 mph.

    Low: 74 °F

    Increasing
    Clouds

  • Friday

    Friday: Cloudy, then gradually becoming mostly sunny, with a high near 98. Heat index values as high as 106. South wind 10 to 15 mph, with gusts as high as 20 mph.

    High: 98 °F

    Decreasing
    Clouds

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 75. South wind 5 to 10 mph.

    Low: 75 °F

    Mostly Cloudy

  • Saturday

    Saturday: Patchy fog before 9am. Otherwise, partly sunny, with a high near 97. Heat index values as high as 104. South wind 5 to 10 mph, with gusts as high as 20 mph.

    High: 97 °F

    Patchy Fog
    then Mostly
    Sunny

  • Saturday Night

    Saturday Night: Mostly cloudy, with a low around 74. South southeast wind around 10 mph, with gusts as high as 20 mph.

    Low: 74 °F

    Mostly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 97 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    Low: 74 °F

    Mostly Cloudy

  • Monday

    Monday: Partly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 30 mph.

    High: 97 °F

    Partly Sunny

  • Monday Night

    Monday Night: A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.

    Low: 74 °F

    Partly Cloudy
    then Slight
    Chance
    T-storms

Detailed Forecast

Tonight
Increasing clouds, with a low around 74. South southeast wind around 10 mph.
Friday
Cloudy, then gradually becoming mostly sunny, with a high near 98. Heat index values as high as 106. South wind 10 to 15 mph, with gusts as high as 20 mph.
Friday Night
Mostly cloudy, with a low around 75. South wind 5 to 10 mph.
Saturday
Patchy fog before 9am. Otherwise, partly sunny, with a high near 97. Heat index values as high as 104. South wind 5 to 10 mph, with gusts as high as 20 mph.
Saturday Night
Mostly cloudy, with a low around 74. South southeast wind around 10 mph, with gusts as high as 20 mph.
Sunday
Partly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 30 mph.
Sunday Night
Mostly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Monday
Partly sunny, with a high near 97. South wind 10 to 15 mph, with gusts as high as 30 mph.
Monday Night
A 20 percent chance of showers and thunderstorms after 1am. Mostly cloudy, with a low around 74. South southeast wind 10 to 15 mph, with gusts as high as 30 mph.
Tuesday
A 30 percent chance of showers and thunderstorms, mainly before 1pm. Partly sunny, with a high near 96.
Tuesday Night
Mostly clear, with a low around 67.
Wednesday
Sunny, with a high near 95.
Wednesday Night
Partly cloudy, with a low around 66.
Thursday
Sunny, with a high near 92.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
San Marcos TX
 29.88°N 97.94°W (Elev. 577 ft)
Last Update:
6:44 pm CDT May 15, 2025
Forecast Valid:
7pm CDT May 15, 2025-6pm CDT May 22, 2025
 
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